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// SPDX-License-Identifier: GPL-2.0-or-later /* RxRPC key management * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) * * RxRPC keys should have a description of describing their purpose: * "[email protected]> */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <crypto/skcipher.h> #include <linux/module.h> #include <linux/net.h> #include <linux/skbuff.h> #include <linux/key-type.h> #include <linux/ctype.h> #include <linux/slab.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include <keys/rxrpc-type.h> #include <keys/user-type.h> #include "ar-internal.h" static int rxrpc_vet_description_s(const char *); static int rxrpc_preparse_s(struct key_preparsed_payload *); static void rxrpc_free_preparse_s(struct key_preparsed_payload *); static void rxrpc_destroy_s(struct key *); static void rxrpc_describe_s(const struct key *, struct seq_file *); /* * rxrpc server keys take "<serviceId>:<securityIndex>[:<sec-specific>]" as the * description and the key material as the payload. */ struct key_type key_type_rxrpc_s = { .name = "rxrpc_s", .flags = KEY_TYPE_NET_DOMAIN, .vet_description = rxrpc_vet_description_s, .preparse = rxrpc_preparse_s, .free_preparse = rxrpc_free_preparse_s, .instantiate = generic_key_instantiate, .destroy = rxrpc_destroy_s, .describe = rxrpc_describe_s, }; /* * Vet the description for an RxRPC server key. */ static int rxrpc_vet_description_s(const char *desc) { unsigned long service, sec_class; char *p; service = simple_strtoul(desc, &p, 10); if (*p != ':' || service > 65535) return -EINVAL; sec_class = simple_strtoul(p + 1, &p, 10); if ((*p && *p != ':') || sec_class < 1 || sec_class > 255) return -EINVAL; return 0; } /* * Preparse a server secret key. */ static int rxrpc_preparse_s(struct key_preparsed_payload *prep) { const struct rxrpc_security *sec; unsigned int service, sec_class; int n; _enter("%zu", prep->datalen); if (!prep->orig_description) return -EINVAL; if (sscanf(prep->orig_description, "%u:%u%n", &service, &sec_class, &n) != 2) return -EINVAL; sec = rxrpc_security_lookup(sec_class); if (!sec) return -ENOPKG; prep->payload.data[1] = (struct rxrpc_security *)sec; if (!sec->preparse_server_key) return -EINVAL; return sec->preparse_server_key(prep); } static void rxrpc_free_preparse_s(struct key_preparsed_payload *prep) { const struct rxrpc_security *sec = prep->payload.data[1]; if (sec && sec->free_preparse_server_key) sec->free_preparse_server_key(prep); } static void rxrpc_destroy_s(struct key *key) { const struct rxrpc_security *sec = key->payload.data[1]; if (sec && sec->destroy_server_key) sec->destroy_server_key(key); } static void rxrpc_describe_s(const struct key *key, struct seq_file *m) { const struct rxrpc_security *sec = key->payload.data[1]; seq_puts(m, key->description); if (sec && sec->describe_server_key) sec->describe_server_key(key, m); } /* * grab the security keyring for a server socket */ int rxrpc_server_keyring(struct rxrpc_sock *rx, sockptr_t optval, int optlen) { struct key *key; char *description; _enter(""); if (optlen <= 0 || optlen > PAGE_SIZE - 1) return -EINVAL; description = memdup_sockptr_nul(optval, optlen); if (IS_ERR(description)) return PTR_ERR(description); key = request_key(&key_type_keyring, description, NULL); if (IS_ERR(key)) { kfree(description); _leave(" = %ld", PTR_ERR(key)); return PTR_ERR(key); } rx->securities = key; kfree(description); _leave(" = 0 [key %x]", key->serial); return 0; } /** * rxrpc_sock_set_security_keyring - Set the security keyring for a kernel service * @sk: The socket to set the keyring on * @keyring: The keyring to set * * Set the server security keyring on an rxrpc socket. This is used to provide * the encryption keys for a kernel service. */ int rxrpc_sock_set_security_keyring(struct sock *sk, struct key *keyring) { struct rxrpc_sock *rx = rxrpc_sk(sk); int ret = 0; lock_sock(sk); if (rx->securities) ret = -EINVAL; else if (rx->sk.sk_state != RXRPC_UNBOUND) ret = -EISCONN; else rx->securities = key_get(keyring); release_sock(sk); return ret; } EXPORT_SYMBOL(rxrpc_sock_set_security_keyring);
linux-master
net/rxrpc/server_key.c
// SPDX-License-Identifier: GPL-2.0-or-later /* AF_RXRPC implementation * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.h> #include <linux/kernel.h> #include <linux/net.h> #include <linux/slab.h> #include <linux/skbuff.h> #include <linux/random.h> #include <linux/poll.h> #include <linux/proc_fs.h> #include <linux/key-type.h> #include <net/net_namespace.h> #include <net/sock.h> #include <net/af_rxrpc.h> #define CREATE_TRACE_POINTS #include "ar-internal.h" MODULE_DESCRIPTION("RxRPC network protocol"); MODULE_AUTHOR("Red Hat, Inc."); MODULE_LICENSE("GPL"); MODULE_ALIAS_NETPROTO(PF_RXRPC); unsigned int rxrpc_debug; // = RXRPC_DEBUG_KPROTO; module_param_named(debug, rxrpc_debug, uint, 0644); MODULE_PARM_DESC(debug, "RxRPC debugging mask"); static struct proto rxrpc_proto; static const struct proto_ops rxrpc_rpc_ops; /* current debugging ID */ atomic_t rxrpc_debug_id; EXPORT_SYMBOL(rxrpc_debug_id); /* count of skbs currently in use */ atomic_t rxrpc_n_rx_skbs; struct workqueue_struct *rxrpc_workqueue; static void rxrpc_sock_destructor(struct sock *); /* * see if an RxRPC socket is currently writable */ static inline int rxrpc_writable(struct sock *sk) { return refcount_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf; } /* * wait for write bufferage to become available */ static void rxrpc_write_space(struct sock *sk) { _enter("%p", sk); rcu_read_lock(); if (rxrpc_writable(sk)) { struct socket_wq *wq = rcu_dereference(sk->sk_wq); if (skwq_has_sleeper(wq)) wake_up_interruptible(&wq->wait); sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); } rcu_read_unlock(); } /* * validate an RxRPC address */ static int rxrpc_validate_address(struct rxrpc_sock *rx, struct sockaddr_rxrpc *srx, int len) { unsigned int tail; if (len < sizeof(struct sockaddr_rxrpc)) return -EINVAL; if (srx->srx_family != AF_RXRPC) return -EAFNOSUPPORT; if (srx->transport_type != SOCK_DGRAM) return -ESOCKTNOSUPPORT; len -= offsetof(struct sockaddr_rxrpc, transport); if (srx->transport_len < sizeof(sa_family_t) || srx->transport_len > len) return -EINVAL; switch (srx->transport.family) { case AF_INET: if (rx->family != AF_INET && rx->family != AF_INET6) return -EAFNOSUPPORT; if (srx->transport_len < sizeof(struct sockaddr_in)) return -EINVAL; tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad); break; #ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: if (rx->family != AF_INET6) return -EAFNOSUPPORT; if (srx->transport_len < sizeof(struct sockaddr_in6)) return -EINVAL; tail = offsetof(struct sockaddr_rxrpc, transport) + sizeof(struct sockaddr_in6); break; #endif default: return -EAFNOSUPPORT; } if (tail < len) memset((void *)srx + tail, 0, len - tail); _debug("INET: %pISp", &srx->transport); return 0; } /* * bind a local address to an RxRPC socket */ static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len) { struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr; struct rxrpc_local *local; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); u16 service_id; int ret; _enter("%p,%p,%d", rx, saddr, len); ret = rxrpc_validate_address(rx, srx, len); if (ret < 0) goto error; service_id = srx->srx_service; lock_sock(&rx->sk); switch (rx->sk.sk_state) { case RXRPC_UNBOUND: rx->srx = *srx; local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx); if (IS_ERR(local)) { ret = PTR_ERR(local); goto error_unlock; } if (service_id) { write_lock(&local->services_lock); if (local->service) goto service_in_use; rx->local = local; local->service = rx; write_unlock(&local->services_lock); rx->sk.sk_state = RXRPC_SERVER_BOUND; } else { rx->local = local; rx->sk.sk_state = RXRPC_CLIENT_BOUND; } break; case RXRPC_SERVER_BOUND: ret = -EINVAL; if (service_id == 0) goto error_unlock; ret = -EADDRINUSE; if (service_id == rx->srx.srx_service) goto error_unlock; ret = -EINVAL; srx->srx_service = rx->srx.srx_service; if (memcmp(srx, &rx->srx, sizeof(*srx)) != 0) goto error_unlock; rx->second_service = service_id; rx->sk.sk_state = RXRPC_SERVER_BOUND2; break; default: ret = -EINVAL; goto error_unlock; } release_sock(&rx->sk); _leave(" = 0"); return 0; service_in_use: write_unlock(&local->services_lock); rxrpc_unuse_local(local, rxrpc_local_unuse_bind); rxrpc_put_local(local, rxrpc_local_put_bind); ret = -EADDRINUSE; error_unlock: release_sock(&rx->sk); error: _leave(" = %d", ret); return ret; } /* * set the number of pending calls permitted on a listening socket */ static int rxrpc_listen(struct socket *sock, int backlog) { struct sock *sk = sock->sk; struct rxrpc_sock *rx = rxrpc_sk(sk); unsigned int max, old; int ret; _enter("%p,%d", rx, backlog); lock_sock(&rx->sk); switch (rx->sk.sk_state) { case RXRPC_UNBOUND: ret = -EADDRNOTAVAIL; break; case RXRPC_SERVER_BOUND: case RXRPC_SERVER_BOUND2: ASSERT(rx->local != NULL); max = READ_ONCE(rxrpc_max_backlog); ret = -EINVAL; if (backlog == INT_MAX) backlog = max; else if (backlog < 0 || backlog > max) break; old = sk->sk_max_ack_backlog; sk->sk_max_ack_backlog = backlog; ret = rxrpc_service_prealloc(rx, GFP_KERNEL); if (ret == 0) rx->sk.sk_state = RXRPC_SERVER_LISTENING; else sk->sk_max_ack_backlog = old; break; case RXRPC_SERVER_LISTENING: if (backlog == 0) { rx->sk.sk_state = RXRPC_SERVER_LISTEN_DISABLED; sk->sk_max_ack_backlog = 0; rxrpc_discard_prealloc(rx); ret = 0; break; } fallthrough; default: ret = -EBUSY; break; } release_sock(&rx->sk); _leave(" = %d", ret); return ret; } /** * rxrpc_kernel_begin_call - Allow a kernel service to begin a call * @sock: The socket on which to make the call * @srx: The address of the peer to contact * @key: The security context to use (defaults to socket setting) * @user_call_ID: The ID to use * @tx_total_len: Total length of data to transmit during the call (or -1) * @hard_timeout: The maximum lifespan of the call in sec * @gfp: The allocation constraints * @notify_rx: Where to send notifications instead of socket queue * @upgrade: Request service upgrade for call * @interruptibility: The call is interruptible, or can be canceled. * @debug_id: The debug ID for tracing to be assigned to the call * * Allow a kernel service to begin a call on the nominated socket. This just * sets up all the internal tracking structures and allocates connection and * call IDs as appropriate. The call to be used is returned. * * The default socket destination address and security may be overridden by * supplying @srx and @key. */ struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, s64 tx_total_len, u32 hard_timeout, gfp_t gfp, rxrpc_notify_rx_t notify_rx, bool upgrade, enum rxrpc_interruptibility interruptibility, unsigned int debug_id) { struct rxrpc_conn_parameters cp; struct rxrpc_call_params p; struct rxrpc_call *call; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); int ret; _enter(",,%x,%lx", key_serial(key), user_call_ID); ret = rxrpc_validate_address(rx, srx, sizeof(*srx)); if (ret < 0) return ERR_PTR(ret); lock_sock(&rx->sk); if (!key) key = rx->key; if (key && !key->payload.data[0]) key = NULL; /* a no-security key */ memset(&p, 0, sizeof(p)); p.user_call_ID = user_call_ID; p.tx_total_len = tx_total_len; p.interruptibility = interruptibility; p.kernel = true; p.timeouts.hard = hard_timeout; memset(&cp, 0, sizeof(cp)); cp.local = rx->local; cp.key = key; cp.security_level = rx->min_sec_level; cp.exclusive = false; cp.upgrade = upgrade; cp.service_id = srx->srx_service; call = rxrpc_new_client_call(rx, &cp, srx, &p, gfp, debug_id); /* The socket has been unlocked. */ if (!IS_ERR(call)) { call->notify_rx = notify_rx; mutex_unlock(&call->user_mutex); } _leave(" = %p", call); return call; } EXPORT_SYMBOL(rxrpc_kernel_begin_call); /* * Dummy function used to stop the notifier talking to recvmsg(). */ static void rxrpc_dummy_notify_rx(struct sock *sk, struct rxrpc_call *rxcall, unsigned long call_user_ID) { } /** * rxrpc_kernel_shutdown_call - Allow a kernel service to shut down a call it was using * @sock: The socket the call is on * @call: The call to end * * Allow a kernel service to shut down a call it was using. The call must be * complete before this is called (the call should be aborted if necessary). */ void rxrpc_kernel_shutdown_call(struct socket *sock, struct rxrpc_call *call) { _enter("%d{%d}", call->debug_id, refcount_read(&call->ref)); mutex_lock(&call->user_mutex); if (!test_bit(RXRPC_CALL_RELEASED, &call->flags)) { rxrpc_release_call(rxrpc_sk(sock->sk), call); /* Make sure we're not going to call back into a kernel service */ if (call->notify_rx) { spin_lock(&call->notify_lock); call->notify_rx = rxrpc_dummy_notify_rx; spin_unlock(&call->notify_lock); } } mutex_unlock(&call->user_mutex); } EXPORT_SYMBOL(rxrpc_kernel_shutdown_call); /** * rxrpc_kernel_put_call - Release a reference to a call * @sock: The socket the call is on * @call: The call to put * * Drop the application's ref on an rxrpc call. */ void rxrpc_kernel_put_call(struct socket *sock, struct rxrpc_call *call) { rxrpc_put_call(call, rxrpc_call_put_kernel); } EXPORT_SYMBOL(rxrpc_kernel_put_call); /** * rxrpc_kernel_check_life - Check to see whether a call is still alive * @sock: The socket the call is on * @call: The call to check * * Allow a kernel service to find out whether a call is still alive - whether * it has completed successfully and all received data has been consumed. */ bool rxrpc_kernel_check_life(const struct socket *sock, const struct rxrpc_call *call) { if (!rxrpc_call_is_complete(call)) return true; if (call->completion != RXRPC_CALL_SUCCEEDED) return false; return !skb_queue_empty(&call->recvmsg_queue); } EXPORT_SYMBOL(rxrpc_kernel_check_life); /** * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call. * @sock: The socket the call is on * @call: The call to query * * Allow a kernel service to retrieve the epoch value from a service call to * see if the client at the other end rebooted. */ u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call) { return call->conn->proto.epoch; } EXPORT_SYMBOL(rxrpc_kernel_get_epoch); /** * rxrpc_kernel_new_call_notification - Get notifications of new calls * @sock: The socket to intercept received messages on * @notify_new_call: Function to be called when new calls appear * @discard_new_call: Function to discard preallocated calls * * Allow a kernel service to be given notifications about new calls. */ void rxrpc_kernel_new_call_notification( struct socket *sock, rxrpc_notify_new_call_t notify_new_call, rxrpc_discard_new_call_t discard_new_call) { struct rxrpc_sock *rx = rxrpc_sk(sock->sk); rx->notify_new_call = notify_new_call; rx->discard_new_call = discard_new_call; } EXPORT_SYMBOL(rxrpc_kernel_new_call_notification); /** * rxrpc_kernel_set_max_life - Set maximum lifespan on a call * @sock: The socket the call is on * @call: The call to configure * @hard_timeout: The maximum lifespan of the call in jiffies * * Set the maximum lifespan of a call. The call will end with ETIME or * ETIMEDOUT if it takes longer than this. */ void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call, unsigned long hard_timeout) { unsigned long now; mutex_lock(&call->user_mutex); now = jiffies; hard_timeout += now; WRITE_ONCE(call->expect_term_by, hard_timeout); rxrpc_reduce_call_timer(call, hard_timeout, now, rxrpc_timer_set_for_hard); mutex_unlock(&call->user_mutex); } EXPORT_SYMBOL(rxrpc_kernel_set_max_life); /* * connect an RxRPC socket * - this just targets it at a specific destination; no actual connection * negotiation takes place */ static int rxrpc_connect(struct socket *sock, struct sockaddr *addr, int addr_len, int flags) { struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); int ret; _enter("%p,%p,%d,%d", rx, addr, addr_len, flags); ret = rxrpc_validate_address(rx, srx, addr_len); if (ret < 0) { _leave(" = %d [bad addr]", ret); return ret; } lock_sock(&rx->sk); ret = -EISCONN; if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) goto error; switch (rx->sk.sk_state) { case RXRPC_UNBOUND: rx->sk.sk_state = RXRPC_CLIENT_UNBOUND; break; case RXRPC_CLIENT_UNBOUND: case RXRPC_CLIENT_BOUND: break; default: ret = -EBUSY; goto error; } rx->connect_srx = *srx; set_bit(RXRPC_SOCK_CONNECTED, &rx->flags); ret = 0; error: release_sock(&rx->sk); return ret; } /* * send a message through an RxRPC socket * - in a client this does a number of things: * - finds/sets up a connection for the security specified (if any) * - initiates a call (ID in control data) * - ends the request phase of a call (if MSG_MORE is not set) * - sends a call data packet * - may send an abort (abort code in control data) */ static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len) { struct rxrpc_local *local; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); int ret; _enter(",{%d},,%zu", rx->sk.sk_state, len); if (m->msg_flags & MSG_OOB) return -EOPNOTSUPP; if (m->msg_name) { ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen); if (ret < 0) { _leave(" = %d [bad addr]", ret); return ret; } } lock_sock(&rx->sk); switch (rx->sk.sk_state) { case RXRPC_UNBOUND: case RXRPC_CLIENT_UNBOUND: rx->srx.srx_family = AF_RXRPC; rx->srx.srx_service = 0; rx->srx.transport_type = SOCK_DGRAM; rx->srx.transport.family = rx->family; switch (rx->family) { case AF_INET: rx->srx.transport_len = sizeof(struct sockaddr_in); break; #ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: rx->srx.transport_len = sizeof(struct sockaddr_in6); break; #endif default: ret = -EAFNOSUPPORT; goto error_unlock; } local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx); if (IS_ERR(local)) { ret = PTR_ERR(local); goto error_unlock; } rx->local = local; rx->sk.sk_state = RXRPC_CLIENT_BOUND; fallthrough; case RXRPC_CLIENT_BOUND: if (!m->msg_name && test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) { m->msg_name = &rx->connect_srx; m->msg_namelen = sizeof(rx->connect_srx); } fallthrough; case RXRPC_SERVER_BOUND: case RXRPC_SERVER_LISTENING: ret = rxrpc_do_sendmsg(rx, m, len); /* The socket has been unlocked */ goto out; default: ret = -EINVAL; goto error_unlock; } error_unlock: release_sock(&rx->sk); out: _leave(" = %d", ret); return ret; } int rxrpc_sock_set_min_security_level(struct sock *sk, unsigned int val) { if (sk->sk_state != RXRPC_UNBOUND) return -EISCONN; if (val > RXRPC_SECURITY_MAX) return -EINVAL; lock_sock(sk); rxrpc_sk(sk)->min_sec_level = val; release_sock(sk); return 0; } EXPORT_SYMBOL(rxrpc_sock_set_min_security_level); /* * set RxRPC socket options */ static int rxrpc_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval, unsigned int optlen) { struct rxrpc_sock *rx = rxrpc_sk(sock->sk); unsigned int min_sec_level; u16 service_upgrade[2]; int ret; _enter(",%d,%d,,%d", level, optname, optlen); lock_sock(&rx->sk); ret = -EOPNOTSUPP; if (level == SOL_RXRPC) { switch (optname) { case RXRPC_EXCLUSIVE_CONNECTION: ret = -EINVAL; if (optlen != 0) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNBOUND) goto error; rx->exclusive = true; goto success; case RXRPC_SECURITY_KEY: ret = -EINVAL; if (rx->key) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNBOUND) goto error; ret = rxrpc_request_key(rx, optval, optlen); goto error; case RXRPC_SECURITY_KEYRING: ret = -EINVAL; if (rx->key) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNBOUND) goto error; ret = rxrpc_server_keyring(rx, optval, optlen); goto error; case RXRPC_MIN_SECURITY_LEVEL: ret = -EINVAL; if (optlen != sizeof(unsigned int)) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNBOUND) goto error; ret = copy_from_sockptr(&min_sec_level, optval, sizeof(unsigned int)); if (ret < 0) goto error; ret = -EINVAL; if (min_sec_level > RXRPC_SECURITY_MAX) goto error; rx->min_sec_level = min_sec_level; goto success; case RXRPC_UPGRADEABLE_SERVICE: ret = -EINVAL; if (optlen != sizeof(service_upgrade) || rx->service_upgrade.from != 0) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_SERVER_BOUND2) goto error; ret = -EFAULT; if (copy_from_sockptr(service_upgrade, optval, sizeof(service_upgrade)) != 0) goto error; ret = -EINVAL; if ((service_upgrade[0] != rx->srx.srx_service || service_upgrade[1] != rx->second_service) && (service_upgrade[0] != rx->second_service || service_upgrade[1] != rx->srx.srx_service)) goto error; rx->service_upgrade.from = service_upgrade[0]; rx->service_upgrade.to = service_upgrade[1]; goto success; default: break; } } success: ret = 0; error: release_sock(&rx->sk); return ret; } /* * Get socket options. */ static int rxrpc_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *_optlen) { int optlen; if (level != SOL_RXRPC) return -EOPNOTSUPP; if (get_user(optlen, _optlen)) return -EFAULT; switch (optname) { case RXRPC_SUPPORTED_CMSG: if (optlen < sizeof(int)) return -ETOOSMALL; if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) || put_user(sizeof(int), _optlen)) return -EFAULT; return 0; default: return -EOPNOTSUPP; } } /* * permit an RxRPC socket to be polled */ static __poll_t rxrpc_poll(struct file *file, struct socket *sock, poll_table *wait) { struct sock *sk = sock->sk; struct rxrpc_sock *rx = rxrpc_sk(sk); __poll_t mask; sock_poll_wait(file, sock, wait); mask = 0; /* the socket is readable if there are any messages waiting on the Rx * queue */ if (!list_empty(&rx->recvmsg_q)) mask |= EPOLLIN | EPOLLRDNORM; /* the socket is writable if there is space to add new data to the * socket; there is no guarantee that any particular call in progress * on the socket may have space in the Tx ACK window */ if (rxrpc_writable(sk)) mask |= EPOLLOUT | EPOLLWRNORM; return mask; } /* * create an RxRPC socket */ static int rxrpc_create(struct net *net, struct socket *sock, int protocol, int kern) { struct rxrpc_net *rxnet; struct rxrpc_sock *rx; struct sock *sk; _enter("%p,%d", sock, protocol); /* we support transport protocol UDP/UDP6 only */ if (protocol != PF_INET && IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6) return -EPROTONOSUPPORT; if (sock->type != SOCK_DGRAM) return -ESOCKTNOSUPPORT; sock->ops = &rxrpc_rpc_ops; sock->state = SS_UNCONNECTED; sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern); if (!sk) return -ENOMEM; sock_init_data(sock, sk); sock_set_flag(sk, SOCK_RCU_FREE); sk->sk_state = RXRPC_UNBOUND; sk->sk_write_space = rxrpc_write_space; sk->sk_max_ack_backlog = 0; sk->sk_destruct = rxrpc_sock_destructor; rx = rxrpc_sk(sk); rx->family = protocol; rx->calls = RB_ROOT; spin_lock_init(&rx->incoming_lock); INIT_LIST_HEAD(&rx->sock_calls); INIT_LIST_HEAD(&rx->to_be_accepted); INIT_LIST_HEAD(&rx->recvmsg_q); spin_lock_init(&rx->recvmsg_lock); rwlock_init(&rx->call_lock); memset(&rx->srx, 0, sizeof(rx->srx)); rxnet = rxrpc_net(sock_net(&rx->sk)); timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1); _leave(" = 0 [%p]", rx); return 0; } /* * Kill all the calls on a socket and shut it down. */ static int rxrpc_shutdown(struct socket *sock, int flags) { struct sock *sk = sock->sk; struct rxrpc_sock *rx = rxrpc_sk(sk); int ret = 0; _enter("%p,%d", sk, flags); if (flags != SHUT_RDWR) return -EOPNOTSUPP; if (sk->sk_state == RXRPC_CLOSE) return -ESHUTDOWN; lock_sock(sk); if (sk->sk_state < RXRPC_CLOSE) { sk->sk_state = RXRPC_CLOSE; sk->sk_shutdown = SHUTDOWN_MASK; } else { ret = -ESHUTDOWN; } rxrpc_discard_prealloc(rx); release_sock(sk); return ret; } /* * RxRPC socket destructor */ static void rxrpc_sock_destructor(struct sock *sk) { _enter("%p", sk); rxrpc_purge_queue(&sk->sk_receive_queue); WARN_ON(refcount_read(&sk->sk_wmem_alloc)); WARN_ON(!sk_unhashed(sk)); WARN_ON(sk->sk_socket); if (!sock_flag(sk, SOCK_DEAD)) { printk("Attempt to release alive rxrpc socket: %p\n", sk); return; } } /* * release an RxRPC socket */ static int rxrpc_release_sock(struct sock *sk) { struct rxrpc_sock *rx = rxrpc_sk(sk); _enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt)); /* declare the socket closed for business */ sock_orphan(sk); sk->sk_shutdown = SHUTDOWN_MASK; /* We want to kill off all connections from a service socket * as fast as possible because we can't share these; client * sockets, on the other hand, can share an endpoint. */ switch (sk->sk_state) { case RXRPC_SERVER_BOUND: case RXRPC_SERVER_BOUND2: case RXRPC_SERVER_LISTENING: case RXRPC_SERVER_LISTEN_DISABLED: rx->local->service_closed = true; break; } sk->sk_state = RXRPC_CLOSE; if (rx->local && rx->local->service == rx) { write_lock(&rx->local->services_lock); rx->local->service = NULL; write_unlock(&rx->local->services_lock); } /* try to flush out this socket */ rxrpc_discard_prealloc(rx); rxrpc_release_calls_on_socket(rx); flush_workqueue(rxrpc_workqueue); rxrpc_purge_queue(&sk->sk_receive_queue); rxrpc_unuse_local(rx->local, rxrpc_local_unuse_release_sock); rxrpc_put_local(rx->local, rxrpc_local_put_release_sock); rx->local = NULL; key_put(rx->key); rx->key = NULL; key_put(rx->securities); rx->securities = NULL; sock_put(sk); _leave(" = 0"); return 0; } /* * release an RxRPC BSD socket on close() or equivalent */ static int rxrpc_release(struct socket *sock) { struct sock *sk = sock->sk; _enter("%p{%p}", sock, sk); if (!sk) return 0; sock->sk = NULL; return rxrpc_release_sock(sk); } /* * RxRPC network protocol */ static const struct proto_ops rxrpc_rpc_ops = { .family = PF_RXRPC, .owner = THIS_MODULE, .release = rxrpc_release, .bind = rxrpc_bind, .connect = rxrpc_connect, .socketpair = sock_no_socketpair, .accept = sock_no_accept, .getname = sock_no_getname, .poll = rxrpc_poll, .ioctl = sock_no_ioctl, .listen = rxrpc_listen, .shutdown = rxrpc_shutdown, .setsockopt = rxrpc_setsockopt, .getsockopt = rxrpc_getsockopt, .sendmsg = rxrpc_sendmsg, .recvmsg = rxrpc_recvmsg, .mmap = sock_no_mmap, }; static struct proto rxrpc_proto = { .name = "RXRPC", .owner = THIS_MODULE, .obj_size = sizeof(struct rxrpc_sock), .max_header = sizeof(struct rxrpc_wire_header), }; static const struct net_proto_family rxrpc_family_ops = { .family = PF_RXRPC, .create = rxrpc_create, .owner = THIS_MODULE, }; /* * initialise and register the RxRPC protocol */ static int __init af_rxrpc_init(void) { int ret = -1; BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof_field(struct sk_buff, cb)); ret = -ENOMEM; rxrpc_gen_version_string(); rxrpc_call_jar = kmem_cache_create( "rxrpc_call_jar", sizeof(struct rxrpc_call), 0, SLAB_HWCACHE_ALIGN, NULL); if (!rxrpc_call_jar) { pr_notice("Failed to allocate call jar\n"); goto error_call_jar; } rxrpc_workqueue = alloc_ordered_workqueue("krxrpcd", WQ_HIGHPRI | WQ_MEM_RECLAIM); if (!rxrpc_workqueue) { pr_notice("Failed to allocate work queue\n"); goto error_work_queue; } ret = rxrpc_init_security(); if (ret < 0) { pr_crit("Cannot initialise security\n"); goto error_security; } ret = register_pernet_device(&rxrpc_net_ops); if (ret) goto error_pernet; ret = proto_register(&rxrpc_proto, 1); if (ret < 0) { pr_crit("Cannot register protocol\n"); goto error_proto; } ret = sock_register(&rxrpc_family_ops); if (ret < 0) { pr_crit("Cannot register socket family\n"); goto error_sock; } ret = register_key_type(&key_type_rxrpc); if (ret < 0) { pr_crit("Cannot register client key type\n"); goto error_key_type; } ret = register_key_type(&key_type_rxrpc_s); if (ret < 0) { pr_crit("Cannot register server key type\n"); goto error_key_type_s; } ret = rxrpc_sysctl_init(); if (ret < 0) { pr_crit("Cannot register sysctls\n"); goto error_sysctls; } return 0; error_sysctls: unregister_key_type(&key_type_rxrpc_s); error_key_type_s: unregister_key_type(&key_type_rxrpc); error_key_type: sock_unregister(PF_RXRPC); error_sock: proto_unregister(&rxrpc_proto); error_proto: unregister_pernet_device(&rxrpc_net_ops); error_pernet: rxrpc_exit_security(); error_security: destroy_workqueue(rxrpc_workqueue); error_work_queue: kmem_cache_destroy(rxrpc_call_jar); error_call_jar: return ret; } /* * unregister the RxRPC protocol */ static void __exit af_rxrpc_exit(void) { _enter(""); rxrpc_sysctl_exit(); unregister_key_type(&key_type_rxrpc_s); unregister_key_type(&key_type_rxrpc); sock_unregister(PF_RXRPC); proto_unregister(&rxrpc_proto); unregister_pernet_device(&rxrpc_net_ops); ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0); /* Make sure the local and peer records pinned by any dying connections * are released. */ rcu_barrier(); destroy_workqueue(rxrpc_workqueue); rxrpc_exit_security(); kmem_cache_destroy(rxrpc_call_jar); _leave(""); } module_init(af_rxrpc_init); module_exit(af_rxrpc_exit);
linux-master
net/rxrpc/af_rxrpc.c
// SPDX-License-Identifier: GPL-2.0-or-later /* Kerberos-based RxRPC security * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <crypto/skcipher.h> #include <linux/module.h> #include <linux/net.h> #include <linux/skbuff.h> #include <linux/udp.h> #include <linux/scatterlist.h> #include <linux/ctype.h> #include <linux/slab.h> #include <linux/key-type.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include <keys/rxrpc-type.h> #include "ar-internal.h" #define RXKAD_VERSION 2 #define MAXKRB5TICKETLEN 1024 #define RXKAD_TKT_TYPE_KERBEROS_V5 256 #define ANAME_SZ 40 /* size of authentication name */ #define INST_SZ 40 /* size of principal's instance */ #define REALM_SZ 40 /* size of principal's auth domain */ #define SNAME_SZ 40 /* size of service name */ #define RXKAD_ALIGN 8 struct rxkad_level1_hdr { __be32 data_size; /* true data size (excluding padding) */ }; struct rxkad_level2_hdr { __be32 data_size; /* true data size (excluding padding) */ __be32 checksum; /* decrypted data checksum */ }; static int rxkad_prime_packet_security(struct rxrpc_connection *conn, struct crypto_sync_skcipher *ci); /* * this holds a pinned cipher so that keventd doesn't get called by the cipher * alloc routine, but since we have it to hand, we use it to decrypt RESPONSE * packets */ static struct crypto_sync_skcipher *rxkad_ci; static struct skcipher_request *rxkad_ci_req; static DEFINE_MUTEX(rxkad_ci_mutex); /* * Parse the information from a server key * * The data should be the 8-byte secret key. */ static int rxkad_preparse_server_key(struct key_preparsed_payload *prep) { struct crypto_skcipher *ci; if (prep->datalen != 8) return -EINVAL; memcpy(&prep->payload.data[2], prep->data, 8); ci = crypto_alloc_skcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC); if (IS_ERR(ci)) { _leave(" = %ld", PTR_ERR(ci)); return PTR_ERR(ci); } if (crypto_skcipher_setkey(ci, prep->data, 8) < 0) BUG(); prep->payload.data[0] = ci; _leave(" = 0"); return 0; } static void rxkad_free_preparse_server_key(struct key_preparsed_payload *prep) { if (prep->payload.data[0]) crypto_free_skcipher(prep->payload.data[0]); } static void rxkad_destroy_server_key(struct key *key) { if (key->payload.data[0]) { crypto_free_skcipher(key->payload.data[0]); key->payload.data[0] = NULL; } } /* * initialise connection security */ static int rxkad_init_connection_security(struct rxrpc_connection *conn, struct rxrpc_key_token *token) { struct crypto_sync_skcipher *ci; int ret; _enter("{%d},{%x}", conn->debug_id, key_serial(conn->key)); conn->security_ix = token->security_index; ci = crypto_alloc_sync_skcipher("pcbc(fcrypt)", 0, 0); if (IS_ERR(ci)) { _debug("no cipher"); ret = PTR_ERR(ci); goto error; } if (crypto_sync_skcipher_setkey(ci, token->kad->session_key, sizeof(token->kad->session_key)) < 0) BUG(); switch (conn->security_level) { case RXRPC_SECURITY_PLAIN: case RXRPC_SECURITY_AUTH: case RXRPC_SECURITY_ENCRYPT: break; default: ret = -EKEYREJECTED; goto error; } ret = rxkad_prime_packet_security(conn, ci); if (ret < 0) goto error_ci; conn->rxkad.cipher = ci; return 0; error_ci: crypto_free_sync_skcipher(ci); error: _leave(" = %d", ret); return ret; } /* * Work out how much data we can put in a packet. */ static int rxkad_how_much_data(struct rxrpc_call *call, size_t remain, size_t *_buf_size, size_t *_data_size, size_t *_offset) { size_t shdr, buf_size, chunk; switch (call->conn->security_level) { default: buf_size = chunk = min_t(size_t, remain, RXRPC_JUMBO_DATALEN); shdr = 0; goto out; case RXRPC_SECURITY_AUTH: shdr = sizeof(struct rxkad_level1_hdr); break; case RXRPC_SECURITY_ENCRYPT: shdr = sizeof(struct rxkad_level2_hdr); break; } buf_size = round_down(RXRPC_JUMBO_DATALEN, RXKAD_ALIGN); chunk = buf_size - shdr; if (remain < chunk) buf_size = round_up(shdr + remain, RXKAD_ALIGN); out: *_buf_size = buf_size; *_data_size = chunk; *_offset = shdr; return 0; } /* * prime the encryption state with the invariant parts of a connection's * description */ static int rxkad_prime_packet_security(struct rxrpc_connection *conn, struct crypto_sync_skcipher *ci) { struct skcipher_request *req; struct rxrpc_key_token *token; struct scatterlist sg; struct rxrpc_crypt iv; __be32 *tmpbuf; size_t tmpsize = 4 * sizeof(__be32); _enter(""); if (!conn->key) return 0; tmpbuf = kmalloc(tmpsize, GFP_KERNEL); if (!tmpbuf) return -ENOMEM; req = skcipher_request_alloc(&ci->base, GFP_NOFS); if (!req) { kfree(tmpbuf); return -ENOMEM; } token = conn->key->payload.data[0]; memcpy(&iv, token->kad->session_key, sizeof(iv)); tmpbuf[0] = htonl(conn->proto.epoch); tmpbuf[1] = htonl(conn->proto.cid); tmpbuf[2] = 0; tmpbuf[3] = htonl(conn->security_ix); sg_init_one(&sg, tmpbuf, tmpsize); skcipher_request_set_sync_tfm(req, ci); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, &sg, &sg, tmpsize, iv.x); crypto_skcipher_encrypt(req); skcipher_request_free(req); memcpy(&conn->rxkad.csum_iv, tmpbuf + 2, sizeof(conn->rxkad.csum_iv)); kfree(tmpbuf); _leave(" = 0"); return 0; } /* * Allocate and prepare the crypto request on a call. For any particular call, * this is called serially for the packets, so no lock should be necessary. */ static struct skcipher_request *rxkad_get_call_crypto(struct rxrpc_call *call) { struct crypto_skcipher *tfm = &call->conn->rxkad.cipher->base; return skcipher_request_alloc(tfm, GFP_NOFS); } /* * Clean up the crypto on a call. */ static void rxkad_free_call_crypto(struct rxrpc_call *call) { } /* * partially encrypt a packet (level 1 security) */ static int rxkad_secure_packet_auth(const struct rxrpc_call *call, struct rxrpc_txbuf *txb, struct skcipher_request *req) { struct rxkad_level1_hdr *hdr = (void *)txb->data; struct rxrpc_crypt iv; struct scatterlist sg; size_t pad; u16 check; _enter(""); check = txb->seq ^ ntohl(txb->wire.callNumber); hdr->data_size = htonl((u32)check << 16 | txb->len); txb->len += sizeof(struct rxkad_level1_hdr); pad = txb->len; pad = RXKAD_ALIGN - pad; pad &= RXKAD_ALIGN - 1; if (pad) { memset(txb->data + txb->offset, 0, pad); txb->len += pad; } /* start the encryption afresh */ memset(&iv, 0, sizeof(iv)); sg_init_one(&sg, txb->data, 8); skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x); crypto_skcipher_encrypt(req); skcipher_request_zero(req); _leave(" = 0"); return 0; } /* * wholly encrypt a packet (level 2 security) */ static int rxkad_secure_packet_encrypt(const struct rxrpc_call *call, struct rxrpc_txbuf *txb, struct skcipher_request *req) { const struct rxrpc_key_token *token; struct rxkad_level2_hdr *rxkhdr = (void *)txb->data; struct rxrpc_crypt iv; struct scatterlist sg; size_t pad; u16 check; int ret; _enter(""); check = txb->seq ^ ntohl(txb->wire.callNumber); rxkhdr->data_size = htonl(txb->len | (u32)check << 16); rxkhdr->checksum = 0; txb->len += sizeof(struct rxkad_level2_hdr); pad = txb->len; pad = RXKAD_ALIGN - pad; pad &= RXKAD_ALIGN - 1; if (pad) { memset(txb->data + txb->offset, 0, pad); txb->len += pad; } /* encrypt from the session key */ token = call->conn->key->payload.data[0]; memcpy(&iv, token->kad->session_key, sizeof(iv)); sg_init_one(&sg, txb->data, txb->len); skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, &sg, &sg, txb->len, iv.x); ret = crypto_skcipher_encrypt(req); skcipher_request_zero(req); return ret; } /* * checksum an RxRPC packet header */ static int rxkad_secure_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb) { struct skcipher_request *req; struct rxrpc_crypt iv; struct scatterlist sg; union { __be32 buf[2]; } crypto __aligned(8); u32 x, y; int ret; _enter("{%d{%x}},{#%u},%u,", call->debug_id, key_serial(call->conn->key), txb->seq, txb->len); if (!call->conn->rxkad.cipher) return 0; ret = key_validate(call->conn->key); if (ret < 0) return ret; req = rxkad_get_call_crypto(call); if (!req) return -ENOMEM; /* continue encrypting from where we left off */ memcpy(&iv, call->conn->rxkad.csum_iv.x, sizeof(iv)); /* calculate the security checksum */ x = (ntohl(txb->wire.cid) & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT); x |= txb->seq & 0x3fffffff; crypto.buf[0] = txb->wire.callNumber; crypto.buf[1] = htonl(x); sg_init_one(&sg, crypto.buf, 8); skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x); crypto_skcipher_encrypt(req); skcipher_request_zero(req); y = ntohl(crypto.buf[1]); y = (y >> 16) & 0xffff; if (y == 0) y = 1; /* zero checksums are not permitted */ txb->wire.cksum = htons(y); switch (call->conn->security_level) { case RXRPC_SECURITY_PLAIN: ret = 0; break; case RXRPC_SECURITY_AUTH: ret = rxkad_secure_packet_auth(call, txb, req); break; case RXRPC_SECURITY_ENCRYPT: ret = rxkad_secure_packet_encrypt(call, txb, req); break; default: ret = -EPERM; break; } skcipher_request_free(req); _leave(" = %d [set %x]", ret, y); return ret; } /* * decrypt partial encryption on a packet (level 1 security) */ static int rxkad_verify_packet_1(struct rxrpc_call *call, struct sk_buff *skb, rxrpc_seq_t seq, struct skcipher_request *req) { struct rxkad_level1_hdr sechdr; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct rxrpc_crypt iv; struct scatterlist sg[16]; u32 data_size, buf; u16 check; int ret; _enter(""); if (sp->len < 8) return rxrpc_abort_eproto(call, skb, RXKADSEALEDINCON, rxkad_abort_1_short_header); /* Decrypt the skbuff in-place. TODO: We really want to decrypt * directly into the target buffer. */ sg_init_table(sg, ARRAY_SIZE(sg)); ret = skb_to_sgvec(skb, sg, sp->offset, 8); if (unlikely(ret < 0)) return ret; /* start the decryption afresh */ memset(&iv, 0, sizeof(iv)); skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, sg, sg, 8, iv.x); crypto_skcipher_decrypt(req); skcipher_request_zero(req); /* Extract the decrypted packet length */ if (skb_copy_bits(skb, sp->offset, &sechdr, sizeof(sechdr)) < 0) return rxrpc_abort_eproto(call, skb, RXKADDATALEN, rxkad_abort_1_short_encdata); sp->offset += sizeof(sechdr); sp->len -= sizeof(sechdr); buf = ntohl(sechdr.data_size); data_size = buf & 0xffff; check = buf >> 16; check ^= seq ^ call->call_id; check &= 0xffff; if (check != 0) return rxrpc_abort_eproto(call, skb, RXKADSEALEDINCON, rxkad_abort_1_short_check); if (data_size > sp->len) return rxrpc_abort_eproto(call, skb, RXKADDATALEN, rxkad_abort_1_short_data); sp->len = data_size; _leave(" = 0 [dlen=%x]", data_size); return 0; } /* * wholly decrypt a packet (level 2 security) */ static int rxkad_verify_packet_2(struct rxrpc_call *call, struct sk_buff *skb, rxrpc_seq_t seq, struct skcipher_request *req) { const struct rxrpc_key_token *token; struct rxkad_level2_hdr sechdr; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct rxrpc_crypt iv; struct scatterlist _sg[4], *sg; u32 data_size, buf; u16 check; int nsg, ret; _enter(",{%d}", sp->len); if (sp->len < 8) return rxrpc_abort_eproto(call, skb, RXKADSEALEDINCON, rxkad_abort_2_short_header); /* Decrypt the skbuff in-place. TODO: We really want to decrypt * directly into the target buffer. */ sg = _sg; nsg = skb_shinfo(skb)->nr_frags + 1; if (nsg <= 4) { nsg = 4; } else { sg = kmalloc_array(nsg, sizeof(*sg), GFP_NOIO); if (!sg) return -ENOMEM; } sg_init_table(sg, nsg); ret = skb_to_sgvec(skb, sg, sp->offset, sp->len); if (unlikely(ret < 0)) { if (sg != _sg) kfree(sg); return ret; } /* decrypt from the session key */ token = call->conn->key->payload.data[0]; memcpy(&iv, token->kad->session_key, sizeof(iv)); skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, sg, sg, sp->len, iv.x); crypto_skcipher_decrypt(req); skcipher_request_zero(req); if (sg != _sg) kfree(sg); /* Extract the decrypted packet length */ if (skb_copy_bits(skb, sp->offset, &sechdr, sizeof(sechdr)) < 0) return rxrpc_abort_eproto(call, skb, RXKADDATALEN, rxkad_abort_2_short_len); sp->offset += sizeof(sechdr); sp->len -= sizeof(sechdr); buf = ntohl(sechdr.data_size); data_size = buf & 0xffff; check = buf >> 16; check ^= seq ^ call->call_id; check &= 0xffff; if (check != 0) return rxrpc_abort_eproto(call, skb, RXKADSEALEDINCON, rxkad_abort_2_short_check); if (data_size > sp->len) return rxrpc_abort_eproto(call, skb, RXKADDATALEN, rxkad_abort_2_short_data); sp->len = data_size; _leave(" = 0 [dlen=%x]", data_size); return 0; } /* * Verify the security on a received packet and the subpackets therein. */ static int rxkad_verify_packet(struct rxrpc_call *call, struct sk_buff *skb) { struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct skcipher_request *req; struct rxrpc_crypt iv; struct scatterlist sg; union { __be32 buf[2]; } crypto __aligned(8); rxrpc_seq_t seq = sp->hdr.seq; int ret; u16 cksum; u32 x, y; _enter("{%d{%x}},{#%u}", call->debug_id, key_serial(call->conn->key), seq); if (!call->conn->rxkad.cipher) return 0; req = rxkad_get_call_crypto(call); if (!req) return -ENOMEM; /* continue encrypting from where we left off */ memcpy(&iv, call->conn->rxkad.csum_iv.x, sizeof(iv)); /* validate the security checksum */ x = (call->cid & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT); x |= seq & 0x3fffffff; crypto.buf[0] = htonl(call->call_id); crypto.buf[1] = htonl(x); sg_init_one(&sg, crypto.buf, 8); skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x); crypto_skcipher_encrypt(req); skcipher_request_zero(req); y = ntohl(crypto.buf[1]); cksum = (y >> 16) & 0xffff; if (cksum == 0) cksum = 1; /* zero checksums are not permitted */ if (cksum != sp->hdr.cksum) { ret = rxrpc_abort_eproto(call, skb, RXKADSEALEDINCON, rxkad_abort_bad_checksum); goto out; } switch (call->conn->security_level) { case RXRPC_SECURITY_PLAIN: ret = 0; break; case RXRPC_SECURITY_AUTH: ret = rxkad_verify_packet_1(call, skb, seq, req); break; case RXRPC_SECURITY_ENCRYPT: ret = rxkad_verify_packet_2(call, skb, seq, req); break; default: ret = -ENOANO; break; } out: skcipher_request_free(req); return ret; } /* * issue a challenge */ static int rxkad_issue_challenge(struct rxrpc_connection *conn) { struct rxkad_challenge challenge; struct rxrpc_wire_header whdr; struct msghdr msg; struct kvec iov[2]; size_t len; u32 serial; int ret; _enter("{%d}", conn->debug_id); get_random_bytes(&conn->rxkad.nonce, sizeof(conn->rxkad.nonce)); challenge.version = htonl(2); challenge.nonce = htonl(conn->rxkad.nonce); challenge.min_level = htonl(0); challenge.__padding = 0; msg.msg_name = &conn->peer->srx.transport; msg.msg_namelen = conn->peer->srx.transport_len; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; whdr.epoch = htonl(conn->proto.epoch); whdr.cid = htonl(conn->proto.cid); whdr.callNumber = 0; whdr.seq = 0; whdr.type = RXRPC_PACKET_TYPE_CHALLENGE; whdr.flags = conn->out_clientflag; whdr.userStatus = 0; whdr.securityIndex = conn->security_ix; whdr._rsvd = 0; whdr.serviceId = htons(conn->service_id); iov[0].iov_base = &whdr; iov[0].iov_len = sizeof(whdr); iov[1].iov_base = &challenge; iov[1].iov_len = sizeof(challenge); len = iov[0].iov_len + iov[1].iov_len; serial = atomic_inc_return(&conn->serial); whdr.serial = htonl(serial); ret = kernel_sendmsg(conn->local->socket, &msg, iov, 2, len); if (ret < 0) { trace_rxrpc_tx_fail(conn->debug_id, serial, ret, rxrpc_tx_point_rxkad_challenge); return -EAGAIN; } conn->peer->last_tx_at = ktime_get_seconds(); trace_rxrpc_tx_packet(conn->debug_id, &whdr, rxrpc_tx_point_rxkad_challenge); _leave(" = 0"); return 0; } /* * send a Kerberos security response */ static int rxkad_send_response(struct rxrpc_connection *conn, struct rxrpc_host_header *hdr, struct rxkad_response *resp, const struct rxkad_key *s2) { struct rxrpc_wire_header whdr; struct msghdr msg; struct kvec iov[3]; size_t len; u32 serial; int ret; _enter(""); msg.msg_name = &conn->peer->srx.transport; msg.msg_namelen = conn->peer->srx.transport_len; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; memset(&whdr, 0, sizeof(whdr)); whdr.epoch = htonl(hdr->epoch); whdr.cid = htonl(hdr->cid); whdr.type = RXRPC_PACKET_TYPE_RESPONSE; whdr.flags = conn->out_clientflag; whdr.securityIndex = hdr->securityIndex; whdr.serviceId = htons(hdr->serviceId); iov[0].iov_base = &whdr; iov[0].iov_len = sizeof(whdr); iov[1].iov_base = resp; iov[1].iov_len = sizeof(*resp); iov[2].iov_base = (void *)s2->ticket; iov[2].iov_len = s2->ticket_len; len = iov[0].iov_len + iov[1].iov_len + iov[2].iov_len; serial = atomic_inc_return(&conn->serial); whdr.serial = htonl(serial); ret = kernel_sendmsg(conn->local->socket, &msg, iov, 3, len); if (ret < 0) { trace_rxrpc_tx_fail(conn->debug_id, serial, ret, rxrpc_tx_point_rxkad_response); return -EAGAIN; } conn->peer->last_tx_at = ktime_get_seconds(); _leave(" = 0"); return 0; } /* * calculate the response checksum */ static void rxkad_calc_response_checksum(struct rxkad_response *response) { u32 csum = 1000003; int loop; u8 *p = (u8 *) response; for (loop = sizeof(*response); loop > 0; loop--) csum = csum * 0x10204081 + *p++; response->encrypted.checksum = htonl(csum); } /* * encrypt the response packet */ static int rxkad_encrypt_response(struct rxrpc_connection *conn, struct rxkad_response *resp, const struct rxkad_key *s2) { struct skcipher_request *req; struct rxrpc_crypt iv; struct scatterlist sg[1]; req = skcipher_request_alloc(&conn->rxkad.cipher->base, GFP_NOFS); if (!req) return -ENOMEM; /* continue encrypting from where we left off */ memcpy(&iv, s2->session_key, sizeof(iv)); sg_init_table(sg, 1); sg_set_buf(sg, &resp->encrypted, sizeof(resp->encrypted)); skcipher_request_set_sync_tfm(req, conn->rxkad.cipher); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, sg, sg, sizeof(resp->encrypted), iv.x); crypto_skcipher_encrypt(req); skcipher_request_free(req); return 0; } /* * respond to a challenge packet */ static int rxkad_respond_to_challenge(struct rxrpc_connection *conn, struct sk_buff *skb) { const struct rxrpc_key_token *token; struct rxkad_challenge challenge; struct rxkad_response *resp; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); u32 version, nonce, min_level; int ret = -EPROTO; _enter("{%d,%x}", conn->debug_id, key_serial(conn->key)); if (!conn->key) return rxrpc_abort_conn(conn, skb, RX_PROTOCOL_ERROR, -EPROTO, rxkad_abort_chall_no_key); ret = key_validate(conn->key); if (ret < 0) return rxrpc_abort_conn(conn, skb, RXKADEXPIRED, ret, rxkad_abort_chall_key_expired); if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header), &challenge, sizeof(challenge)) < 0) return rxrpc_abort_conn(conn, skb, RXKADPACKETSHORT, -EPROTO, rxkad_abort_chall_short); version = ntohl(challenge.version); nonce = ntohl(challenge.nonce); min_level = ntohl(challenge.min_level); trace_rxrpc_rx_challenge(conn, sp->hdr.serial, version, nonce, min_level); if (version != RXKAD_VERSION) return rxrpc_abort_conn(conn, skb, RXKADINCONSISTENCY, -EPROTO, rxkad_abort_chall_version); if (conn->security_level < min_level) return rxrpc_abort_conn(conn, skb, RXKADLEVELFAIL, -EACCES, rxkad_abort_chall_level); token = conn->key->payload.data[0]; /* build the response packet */ resp = kzalloc(sizeof(struct rxkad_response), GFP_NOFS); if (!resp) return -ENOMEM; resp->version = htonl(RXKAD_VERSION); resp->encrypted.epoch = htonl(conn->proto.epoch); resp->encrypted.cid = htonl(conn->proto.cid); resp->encrypted.securityIndex = htonl(conn->security_ix); resp->encrypted.inc_nonce = htonl(nonce + 1); resp->encrypted.level = htonl(conn->security_level); resp->kvno = htonl(token->kad->kvno); resp->ticket_len = htonl(token->kad->ticket_len); resp->encrypted.call_id[0] = htonl(conn->channels[0].call_counter); resp->encrypted.call_id[1] = htonl(conn->channels[1].call_counter); resp->encrypted.call_id[2] = htonl(conn->channels[2].call_counter); resp->encrypted.call_id[3] = htonl(conn->channels[3].call_counter); /* calculate the response checksum and then do the encryption */ rxkad_calc_response_checksum(resp); ret = rxkad_encrypt_response(conn, resp, token->kad); if (ret == 0) ret = rxkad_send_response(conn, &sp->hdr, resp, token->kad); kfree(resp); return ret; } /* * decrypt the kerberos IV ticket in the response */ static int rxkad_decrypt_ticket(struct rxrpc_connection *conn, struct key *server_key, struct sk_buff *skb, void *ticket, size_t ticket_len, struct rxrpc_crypt *_session_key, time64_t *_expiry) { struct skcipher_request *req; struct rxrpc_crypt iv, key; struct scatterlist sg[1]; struct in_addr addr; unsigned int life; time64_t issue, now; bool little_endian; u8 *p, *q, *name, *end; _enter("{%d},{%x}", conn->debug_id, key_serial(server_key)); *_expiry = 0; ASSERT(server_key->payload.data[0] != NULL); ASSERTCMP((unsigned long) ticket & 7UL, ==, 0); memcpy(&iv, &server_key->payload.data[2], sizeof(iv)); req = skcipher_request_alloc(server_key->payload.data[0], GFP_NOFS); if (!req) return -ENOMEM; sg_init_one(&sg[0], ticket, ticket_len); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, sg, sg, ticket_len, iv.x); crypto_skcipher_decrypt(req); skcipher_request_free(req); p = ticket; end = p + ticket_len; #define Z(field, fieldl) \ ({ \ u8 *__str = p; \ q = memchr(p, 0, end - p); \ if (!q || q - p > field##_SZ) \ return rxrpc_abort_conn( \ conn, skb, RXKADBADTICKET, -EPROTO, \ rxkad_abort_resp_tkt_##fieldl); \ for (; p < q; p++) \ if (!isprint(*p)) \ return rxrpc_abort_conn( \ conn, skb, RXKADBADTICKET, -EPROTO, \ rxkad_abort_resp_tkt_##fieldl); \ p++; \ __str; \ }) /* extract the ticket flags */ _debug("KIV FLAGS: %x", *p); little_endian = *p & 1; p++; /* extract the authentication name */ name = Z(ANAME, aname); _debug("KIV ANAME: %s", name); /* extract the principal's instance */ name = Z(INST, inst); _debug("KIV INST : %s", name); /* extract the principal's authentication domain */ name = Z(REALM, realm); _debug("KIV REALM: %s", name); if (end - p < 4 + 8 + 4 + 2) return rxrpc_abort_conn(conn, skb, RXKADBADTICKET, -EPROTO, rxkad_abort_resp_tkt_short); /* get the IPv4 address of the entity that requested the ticket */ memcpy(&addr, p, sizeof(addr)); p += 4; _debug("KIV ADDR : %pI4", &addr); /* get the session key from the ticket */ memcpy(&key, p, sizeof(key)); p += 8; _debug("KIV KEY : %08x %08x", ntohl(key.n[0]), ntohl(key.n[1])); memcpy(_session_key, &key, sizeof(key)); /* get the ticket's lifetime */ life = *p++ * 5 * 60; _debug("KIV LIFE : %u", life); /* get the issue time of the ticket */ if (little_endian) { __le32 stamp; memcpy(&stamp, p, 4); issue = rxrpc_u32_to_time64(le32_to_cpu(stamp)); } else { __be32 stamp; memcpy(&stamp, p, 4); issue = rxrpc_u32_to_time64(be32_to_cpu(stamp)); } p += 4; now = ktime_get_real_seconds(); _debug("KIV ISSUE: %llx [%llx]", issue, now); /* check the ticket is in date */ if (issue > now) return rxrpc_abort_conn(conn, skb, RXKADNOAUTH, -EKEYREJECTED, rxkad_abort_resp_tkt_future); if (issue < now - life) return rxrpc_abort_conn(conn, skb, RXKADEXPIRED, -EKEYEXPIRED, rxkad_abort_resp_tkt_expired); *_expiry = issue + life; /* get the service name */ name = Z(SNAME, sname); _debug("KIV SNAME: %s", name); /* get the service instance name */ name = Z(INST, sinst); _debug("KIV SINST: %s", name); return 0; } /* * decrypt the response packet */ static void rxkad_decrypt_response(struct rxrpc_connection *conn, struct rxkad_response *resp, const struct rxrpc_crypt *session_key) { struct skcipher_request *req = rxkad_ci_req; struct scatterlist sg[1]; struct rxrpc_crypt iv; _enter(",,%08x%08x", ntohl(session_key->n[0]), ntohl(session_key->n[1])); mutex_lock(&rxkad_ci_mutex); if (crypto_sync_skcipher_setkey(rxkad_ci, session_key->x, sizeof(*session_key)) < 0) BUG(); memcpy(&iv, session_key, sizeof(iv)); sg_init_table(sg, 1); sg_set_buf(sg, &resp->encrypted, sizeof(resp->encrypted)); skcipher_request_set_sync_tfm(req, rxkad_ci); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, sg, sg, sizeof(resp->encrypted), iv.x); crypto_skcipher_decrypt(req); skcipher_request_zero(req); mutex_unlock(&rxkad_ci_mutex); _leave(""); } /* * verify a response */ static int rxkad_verify_response(struct rxrpc_connection *conn, struct sk_buff *skb) { struct rxkad_response *response; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct rxrpc_crypt session_key; struct key *server_key; time64_t expiry; void *ticket; u32 version, kvno, ticket_len, level; __be32 csum; int ret, i; _enter("{%d}", conn->debug_id); server_key = rxrpc_look_up_server_security(conn, skb, 0, 0); if (IS_ERR(server_key)) { ret = PTR_ERR(server_key); switch (ret) { case -ENOKEY: return rxrpc_abort_conn(conn, skb, RXKADUNKNOWNKEY, ret, rxkad_abort_resp_nokey); case -EKEYEXPIRED: return rxrpc_abort_conn(conn, skb, RXKADEXPIRED, ret, rxkad_abort_resp_key_expired); default: return rxrpc_abort_conn(conn, skb, RXKADNOAUTH, ret, rxkad_abort_resp_key_rejected); } } ret = -ENOMEM; response = kzalloc(sizeof(struct rxkad_response), GFP_NOFS); if (!response) goto temporary_error; if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header), response, sizeof(*response)) < 0) { rxrpc_abort_conn(conn, skb, RXKADPACKETSHORT, -EPROTO, rxkad_abort_resp_short); goto protocol_error; } version = ntohl(response->version); ticket_len = ntohl(response->ticket_len); kvno = ntohl(response->kvno); trace_rxrpc_rx_response(conn, sp->hdr.serial, version, kvno, ticket_len); if (version != RXKAD_VERSION) { rxrpc_abort_conn(conn, skb, RXKADINCONSISTENCY, -EPROTO, rxkad_abort_resp_version); goto protocol_error; } if (ticket_len < 4 || ticket_len > MAXKRB5TICKETLEN) { rxrpc_abort_conn(conn, skb, RXKADTICKETLEN, -EPROTO, rxkad_abort_resp_tkt_len); goto protocol_error; } if (kvno >= RXKAD_TKT_TYPE_KERBEROS_V5) { rxrpc_abort_conn(conn, skb, RXKADUNKNOWNKEY, -EPROTO, rxkad_abort_resp_unknown_tkt); goto protocol_error; } /* extract the kerberos ticket and decrypt and decode it */ ret = -ENOMEM; ticket = kmalloc(ticket_len, GFP_NOFS); if (!ticket) goto temporary_error_free_resp; if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header) + sizeof(*response), ticket, ticket_len) < 0) { rxrpc_abort_conn(conn, skb, RXKADPACKETSHORT, -EPROTO, rxkad_abort_resp_short_tkt); goto protocol_error; } ret = rxkad_decrypt_ticket(conn, server_key, skb, ticket, ticket_len, &session_key, &expiry); if (ret < 0) goto temporary_error_free_ticket; /* use the session key from inside the ticket to decrypt the * response */ rxkad_decrypt_response(conn, response, &session_key); if (ntohl(response->encrypted.epoch) != conn->proto.epoch || ntohl(response->encrypted.cid) != conn->proto.cid || ntohl(response->encrypted.securityIndex) != conn->security_ix) { rxrpc_abort_conn(conn, skb, RXKADSEALEDINCON, -EPROTO, rxkad_abort_resp_bad_param); goto protocol_error_free; } csum = response->encrypted.checksum; response->encrypted.checksum = 0; rxkad_calc_response_checksum(response); if (response->encrypted.checksum != csum) { rxrpc_abort_conn(conn, skb, RXKADSEALEDINCON, -EPROTO, rxkad_abort_resp_bad_checksum); goto protocol_error_free; } for (i = 0; i < RXRPC_MAXCALLS; i++) { u32 call_id = ntohl(response->encrypted.call_id[i]); u32 counter = READ_ONCE(conn->channels[i].call_counter); if (call_id > INT_MAX) { rxrpc_abort_conn(conn, skb, RXKADSEALEDINCON, -EPROTO, rxkad_abort_resp_bad_callid); goto protocol_error_free; } if (call_id < counter) { rxrpc_abort_conn(conn, skb, RXKADSEALEDINCON, -EPROTO, rxkad_abort_resp_call_ctr); goto protocol_error_free; } if (call_id > counter) { if (conn->channels[i].call) { rxrpc_abort_conn(conn, skb, RXKADSEALEDINCON, -EPROTO, rxkad_abort_resp_call_state); goto protocol_error_free; } conn->channels[i].call_counter = call_id; } } if (ntohl(response->encrypted.inc_nonce) != conn->rxkad.nonce + 1) { rxrpc_abort_conn(conn, skb, RXKADOUTOFSEQUENCE, -EPROTO, rxkad_abort_resp_ooseq); goto protocol_error_free; } level = ntohl(response->encrypted.level); if (level > RXRPC_SECURITY_ENCRYPT) { rxrpc_abort_conn(conn, skb, RXKADLEVELFAIL, -EPROTO, rxkad_abort_resp_level); goto protocol_error_free; } conn->security_level = level; /* create a key to hold the security data and expiration time - after * this the connection security can be handled in exactly the same way * as for a client connection */ ret = rxrpc_get_server_data_key(conn, &session_key, expiry, kvno); if (ret < 0) goto temporary_error_free_ticket; kfree(ticket); kfree(response); _leave(" = 0"); return 0; protocol_error_free: kfree(ticket); protocol_error: kfree(response); key_put(server_key); return -EPROTO; temporary_error_free_ticket: kfree(ticket); temporary_error_free_resp: kfree(response); temporary_error: /* Ignore the response packet if we got a temporary error such as * ENOMEM. We just want to send the challenge again. Note that we * also come out this way if the ticket decryption fails. */ key_put(server_key); return ret; } /* * clear the connection security */ static void rxkad_clear(struct rxrpc_connection *conn) { _enter(""); if (conn->rxkad.cipher) crypto_free_sync_skcipher(conn->rxkad.cipher); } /* * Initialise the rxkad security service. */ static int rxkad_init(void) { struct crypto_sync_skcipher *tfm; struct skcipher_request *req; /* pin the cipher we need so that the crypto layer doesn't invoke * keventd to go get it */ tfm = crypto_alloc_sync_skcipher("pcbc(fcrypt)", 0, 0); if (IS_ERR(tfm)) return PTR_ERR(tfm); req = skcipher_request_alloc(&tfm->base, GFP_KERNEL); if (!req) goto nomem_tfm; rxkad_ci_req = req; rxkad_ci = tfm; return 0; nomem_tfm: crypto_free_sync_skcipher(tfm); return -ENOMEM; } /* * Clean up the rxkad security service. */ static void rxkad_exit(void) { crypto_free_sync_skcipher(rxkad_ci); skcipher_request_free(rxkad_ci_req); } /* * RxRPC Kerberos-based security */ const struct rxrpc_security rxkad = { .name = "rxkad", .security_index = RXRPC_SECURITY_RXKAD, .no_key_abort = RXKADUNKNOWNKEY, .init = rxkad_init, .exit = rxkad_exit, .preparse_server_key = rxkad_preparse_server_key, .free_preparse_server_key = rxkad_free_preparse_server_key, .destroy_server_key = rxkad_destroy_server_key, .init_connection_security = rxkad_init_connection_security, .how_much_data = rxkad_how_much_data, .secure_packet = rxkad_secure_packet, .verify_packet = rxkad_verify_packet, .free_call_crypto = rxkad_free_call_crypto, .issue_challenge = rxkad_issue_challenge, .respond_to_challenge = rxkad_respond_to_challenge, .verify_response = rxkad_verify_response, .clear = rxkad_clear, };
linux-master
net/rxrpc/rxkad.c
// SPDX-License-Identifier: GPL-2.0-or-later /* RxRPC individual remote procedure call handling * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/slab.h> #include <linux/module.h> #include <linux/circ_buf.h> #include <linux/spinlock_types.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include "ar-internal.h" const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = { [RXRPC_CALL_UNINITIALISED] = "Uninit ", [RXRPC_CALL_CLIENT_AWAIT_CONN] = "ClWtConn", [RXRPC_CALL_CLIENT_SEND_REQUEST] = "ClSndReq", [RXRPC_CALL_CLIENT_AWAIT_REPLY] = "ClAwtRpl", [RXRPC_CALL_CLIENT_RECV_REPLY] = "ClRcvRpl", [RXRPC_CALL_SERVER_PREALLOC] = "SvPrealc", [RXRPC_CALL_SERVER_SECURING] = "SvSecure", [RXRPC_CALL_SERVER_RECV_REQUEST] = "SvRcvReq", [RXRPC_CALL_SERVER_ACK_REQUEST] = "SvAckReq", [RXRPC_CALL_SERVER_SEND_REPLY] = "SvSndRpl", [RXRPC_CALL_SERVER_AWAIT_ACK] = "SvAwtACK", [RXRPC_CALL_COMPLETE] = "Complete", }; const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = { [RXRPC_CALL_SUCCEEDED] = "Complete", [RXRPC_CALL_REMOTELY_ABORTED] = "RmtAbort", [RXRPC_CALL_LOCALLY_ABORTED] = "LocAbort", [RXRPC_CALL_LOCAL_ERROR] = "LocError", [RXRPC_CALL_NETWORK_ERROR] = "NetError", }; struct kmem_cache *rxrpc_call_jar; static DEFINE_SEMAPHORE(rxrpc_call_limiter, 1000); static DEFINE_SEMAPHORE(rxrpc_kernel_call_limiter, 1000); void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what) { struct rxrpc_local *local = call->local; bool busy; if (!test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) { spin_lock_bh(&local->lock); busy = !list_empty(&call->attend_link); trace_rxrpc_poke_call(call, busy, what); if (!busy && !rxrpc_try_get_call(call, rxrpc_call_get_poke)) busy = true; if (!busy) { list_add_tail(&call->attend_link, &local->call_attend_q); } spin_unlock_bh(&local->lock); if (!busy) rxrpc_wake_up_io_thread(local); } } static void rxrpc_call_timer_expired(struct timer_list *t) { struct rxrpc_call *call = from_timer(call, t, timer); _enter("%d", call->debug_id); if (!__rxrpc_call_is_complete(call)) { trace_rxrpc_timer_expired(call, jiffies); rxrpc_poke_call(call, rxrpc_call_poke_timer); } } void rxrpc_reduce_call_timer(struct rxrpc_call *call, unsigned long expire_at, unsigned long now, enum rxrpc_timer_trace why) { trace_rxrpc_timer(call, why, now); timer_reduce(&call->timer, expire_at); } static struct lock_class_key rxrpc_call_user_mutex_lock_class_key; static void rxrpc_destroy_call(struct work_struct *); /* * find an extant server call * - called in process context with IRQs enabled */ struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx, unsigned long user_call_ID) { struct rxrpc_call *call; struct rb_node *p; _enter("%p,%lx", rx, user_call_ID); read_lock(&rx->call_lock); p = rx->calls.rb_node; while (p) { call = rb_entry(p, struct rxrpc_call, sock_node); if (user_call_ID < call->user_call_ID) p = p->rb_left; else if (user_call_ID > call->user_call_ID) p = p->rb_right; else goto found_extant_call; } read_unlock(&rx->call_lock); _leave(" = NULL"); return NULL; found_extant_call: rxrpc_get_call(call, rxrpc_call_get_sendmsg); read_unlock(&rx->call_lock); _leave(" = %p [%d]", call, refcount_read(&call->ref)); return call; } /* * allocate a new call */ struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp, unsigned int debug_id) { struct rxrpc_call *call; struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk)); call = kmem_cache_zalloc(rxrpc_call_jar, gfp); if (!call) return NULL; mutex_init(&call->user_mutex); /* Prevent lockdep reporting a deadlock false positive between the afs * filesystem and sys_sendmsg() via the mmap sem. */ if (rx->sk.sk_kern_sock) lockdep_set_class(&call->user_mutex, &rxrpc_call_user_mutex_lock_class_key); timer_setup(&call->timer, rxrpc_call_timer_expired, 0); INIT_WORK(&call->destroyer, rxrpc_destroy_call); INIT_LIST_HEAD(&call->link); INIT_LIST_HEAD(&call->wait_link); INIT_LIST_HEAD(&call->accept_link); INIT_LIST_HEAD(&call->recvmsg_link); INIT_LIST_HEAD(&call->sock_link); INIT_LIST_HEAD(&call->attend_link); INIT_LIST_HEAD(&call->tx_sendmsg); INIT_LIST_HEAD(&call->tx_buffer); skb_queue_head_init(&call->recvmsg_queue); skb_queue_head_init(&call->rx_oos_queue); init_waitqueue_head(&call->waitq); spin_lock_init(&call->notify_lock); spin_lock_init(&call->tx_lock); refcount_set(&call->ref, 1); call->debug_id = debug_id; call->tx_total_len = -1; call->next_rx_timo = 20 * HZ; call->next_req_timo = 1 * HZ; call->ackr_window = 1; call->ackr_wtop = 1; memset(&call->sock_node, 0xed, sizeof(call->sock_node)); call->rx_winsize = rxrpc_rx_window_size; call->tx_winsize = 16; if (RXRPC_TX_SMSS > 2190) call->cong_cwnd = 2; else if (RXRPC_TX_SMSS > 1095) call->cong_cwnd = 3; else call->cong_cwnd = 4; call->cong_ssthresh = RXRPC_TX_MAX_WINDOW; call->rxnet = rxnet; call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK; atomic_inc(&rxnet->nr_calls); return call; } /* * Allocate a new client call. */ static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx, struct sockaddr_rxrpc *srx, struct rxrpc_conn_parameters *cp, struct rxrpc_call_params *p, gfp_t gfp, unsigned int debug_id) { struct rxrpc_call *call; ktime_t now; int ret; _enter(""); call = rxrpc_alloc_call(rx, gfp, debug_id); if (!call) return ERR_PTR(-ENOMEM); now = ktime_get_real(); call->acks_latest_ts = now; call->cong_tstamp = now; call->dest_srx = *srx; call->interruptibility = p->interruptibility; call->tx_total_len = p->tx_total_len; call->key = key_get(cp->key); call->local = rxrpc_get_local(cp->local, rxrpc_local_get_call); call->security_level = cp->security_level; if (p->kernel) __set_bit(RXRPC_CALL_KERNEL, &call->flags); if (cp->upgrade) __set_bit(RXRPC_CALL_UPGRADE, &call->flags); if (cp->exclusive) __set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags); if (p->timeouts.normal) call->next_rx_timo = min(msecs_to_jiffies(p->timeouts.normal), 1UL); if (p->timeouts.idle) call->next_req_timo = min(msecs_to_jiffies(p->timeouts.idle), 1UL); if (p->timeouts.hard) call->hard_timo = p->timeouts.hard * HZ; ret = rxrpc_init_client_call_security(call); if (ret < 0) { rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret); rxrpc_put_call(call, rxrpc_call_put_discard_error); return ERR_PTR(ret); } rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN); trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), p->user_call_ID, rxrpc_call_new_client); _leave(" = %p", call); return call; } /* * Initiate the call ack/resend/expiry timer. */ void rxrpc_start_call_timer(struct rxrpc_call *call) { unsigned long now = jiffies; unsigned long j = now + MAX_JIFFY_OFFSET; call->delay_ack_at = j; call->ack_lost_at = j; call->resend_at = j; call->ping_at = j; call->keepalive_at = j; call->expect_rx_by = j; call->expect_req_by = j; call->expect_term_by = j + call->hard_timo; call->timer.expires = now; } /* * Wait for a call slot to become available. */ static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp) { struct semaphore *limiter = &rxrpc_call_limiter; if (p->kernel) limiter = &rxrpc_kernel_call_limiter; if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) { down(limiter); return limiter; } return down_interruptible(limiter) < 0 ? NULL : limiter; } /* * Release a call slot. */ static void rxrpc_put_call_slot(struct rxrpc_call *call) { struct semaphore *limiter = &rxrpc_call_limiter; if (test_bit(RXRPC_CALL_KERNEL, &call->flags)) limiter = &rxrpc_kernel_call_limiter; up(limiter); } /* * Start the process of connecting a call. We obtain a peer and a connection * bundle, but the actual association of a call with a connection is offloaded * to the I/O thread to simplify locking. */ static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp) { struct rxrpc_local *local = call->local; int ret = -ENOMEM; _enter("{%d,%lx},", call->debug_id, call->user_call_ID); call->peer = rxrpc_lookup_peer(local, &call->dest_srx, gfp); if (!call->peer) goto error; ret = rxrpc_look_up_bundle(call, gfp); if (ret < 0) goto error; trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call); rxrpc_get_call(call, rxrpc_call_get_io_thread); spin_lock(&local->client_call_lock); list_add_tail(&call->wait_link, &local->new_client_calls); spin_unlock(&local->client_call_lock); rxrpc_wake_up_io_thread(local); return 0; error: __set_bit(RXRPC_CALL_DISCONNECTED, &call->flags); return ret; } /* * Set up a call for the given parameters. * - Called with the socket lock held, which it must release. * - If it returns a call, the call's lock will need releasing by the caller. */ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx, struct rxrpc_conn_parameters *cp, struct sockaddr_rxrpc *srx, struct rxrpc_call_params *p, gfp_t gfp, unsigned int debug_id) __releases(&rx->sk.sk_lock.slock) __acquires(&call->user_mutex) { struct rxrpc_call *call, *xcall; struct rxrpc_net *rxnet; struct semaphore *limiter; struct rb_node *parent, **pp; int ret; _enter("%p,%lx", rx, p->user_call_ID); limiter = rxrpc_get_call_slot(p, gfp); if (!limiter) { release_sock(&rx->sk); return ERR_PTR(-ERESTARTSYS); } call = rxrpc_alloc_client_call(rx, srx, cp, p, gfp, debug_id); if (IS_ERR(call)) { release_sock(&rx->sk); up(limiter); _leave(" = %ld", PTR_ERR(call)); return call; } /* We need to protect a partially set up call against the user as we * will be acting outside the socket lock. */ mutex_lock(&call->user_mutex); /* Publish the call, even though it is incompletely set up as yet */ write_lock(&rx->call_lock); pp = &rx->calls.rb_node; parent = NULL; while (*pp) { parent = *pp; xcall = rb_entry(parent, struct rxrpc_call, sock_node); if (p->user_call_ID < xcall->user_call_ID) pp = &(*pp)->rb_left; else if (p->user_call_ID > xcall->user_call_ID) pp = &(*pp)->rb_right; else goto error_dup_user_ID; } rcu_assign_pointer(call->socket, rx); call->user_call_ID = p->user_call_ID; __set_bit(RXRPC_CALL_HAS_USERID, &call->flags); rxrpc_get_call(call, rxrpc_call_get_userid); rb_link_node(&call->sock_node, parent, pp); rb_insert_color(&call->sock_node, &rx->calls); list_add(&call->sock_link, &rx->sock_calls); write_unlock(&rx->call_lock); rxnet = call->rxnet; spin_lock(&rxnet->call_lock); list_add_tail_rcu(&call->link, &rxnet->calls); spin_unlock(&rxnet->call_lock); /* From this point on, the call is protected by its own lock. */ release_sock(&rx->sk); /* Set up or get a connection record and set the protocol parameters, * including channel number and call ID. */ ret = rxrpc_connect_call(call, gfp); if (ret < 0) goto error_attached_to_socket; _leave(" = %p [new]", call); return call; /* We unexpectedly found the user ID in the list after taking * the call_lock. This shouldn't happen unless the user races * with itself and tries to add the same user ID twice at the * same time in different threads. */ error_dup_user_ID: write_unlock(&rx->call_lock); release_sock(&rx->sk); rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST); trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0, rxrpc_call_see_userid_exists); mutex_unlock(&call->user_mutex); rxrpc_put_call(call, rxrpc_call_put_userid_exists); _leave(" = -EEXIST"); return ERR_PTR(-EEXIST); /* We got an error, but the call is attached to the socket and is in * need of release. However, we might now race with recvmsg() when it * completion notifies the socket. Return 0 from sys_sendmsg() and * leave the error to recvmsg() to deal with. */ error_attached_to_socket: trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret, rxrpc_call_see_connect_failed); rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret); _leave(" = c=%08x [err]", call->debug_id); return call; } /* * Set up an incoming call. call->conn points to the connection. * This is called in BH context and isn't allowed to fail. */ void rxrpc_incoming_call(struct rxrpc_sock *rx, struct rxrpc_call *call, struct sk_buff *skb) { struct rxrpc_connection *conn = call->conn; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); u32 chan; _enter(",%d", call->conn->debug_id); rcu_assign_pointer(call->socket, rx); call->call_id = sp->hdr.callNumber; call->dest_srx.srx_service = sp->hdr.serviceId; call->cid = sp->hdr.cid; call->cong_tstamp = skb->tstamp; __set_bit(RXRPC_CALL_EXPOSED, &call->flags); rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING); spin_lock(&conn->state_lock); switch (conn->state) { case RXRPC_CONN_SERVICE_UNSECURED: case RXRPC_CONN_SERVICE_CHALLENGING: rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING); break; case RXRPC_CONN_SERVICE: rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST); break; case RXRPC_CONN_ABORTED: rxrpc_set_call_completion(call, conn->completion, conn->abort_code, conn->error); break; default: BUG(); } rxrpc_get_call(call, rxrpc_call_get_io_thread); /* Set the channel for this call. We don't get channel_lock as we're * only defending against the data_ready handler (which we're called * from) and the RESPONSE packet parser (which is only really * interested in call_counter and can cope with a disagreement with the * call pointer). */ chan = sp->hdr.cid & RXRPC_CHANNELMASK; conn->channels[chan].call_counter = call->call_id; conn->channels[chan].call_id = call->call_id; conn->channels[chan].call = call; spin_unlock(&conn->state_lock); spin_lock(&conn->peer->lock); hlist_add_head(&call->error_link, &conn->peer->error_targets); spin_unlock(&conn->peer->lock); rxrpc_start_call_timer(call); _leave(""); } /* * Note the re-emergence of a call. */ void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why) { if (call) { int r = refcount_read(&call->ref); trace_rxrpc_call(call->debug_id, r, 0, why); } } struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why) { int r; if (!call || !__refcount_inc_not_zero(&call->ref, &r)) return NULL; trace_rxrpc_call(call->debug_id, r + 1, 0, why); return call; } /* * Note the addition of a ref on a call. */ void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why) { int r; __refcount_inc(&call->ref, &r); trace_rxrpc_call(call->debug_id, r + 1, 0, why); } /* * Clean up the Rx skb ring. */ static void rxrpc_cleanup_ring(struct rxrpc_call *call) { skb_queue_purge(&call->recvmsg_queue); skb_queue_purge(&call->rx_oos_queue); } /* * Detach a call from its owning socket. */ void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call) { struct rxrpc_connection *conn = call->conn; bool put = false, putu = false; _enter("{%d,%d}", call->debug_id, refcount_read(&call->ref)); trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), call->flags, rxrpc_call_see_release); if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags)) BUG(); rxrpc_put_call_slot(call); /* Make sure we don't get any more notifications */ spin_lock(&rx->recvmsg_lock); if (!list_empty(&call->recvmsg_link)) { _debug("unlinking once-pending call %p { e=%lx f=%lx }", call, call->events, call->flags); list_del(&call->recvmsg_link); put = true; } /* list_empty() must return false in rxrpc_notify_socket() */ call->recvmsg_link.next = NULL; call->recvmsg_link.prev = NULL; spin_unlock(&rx->recvmsg_lock); if (put) rxrpc_put_call(call, rxrpc_call_put_unnotify); write_lock(&rx->call_lock); if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { rb_erase(&call->sock_node, &rx->calls); memset(&call->sock_node, 0xdd, sizeof(call->sock_node)); putu = true; } list_del(&call->sock_link); write_unlock(&rx->call_lock); _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn); if (putu) rxrpc_put_call(call, rxrpc_call_put_userid); _leave(""); } /* * release all the calls associated with a socket */ void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx) { struct rxrpc_call *call; _enter("%p", rx); while (!list_empty(&rx->to_be_accepted)) { call = list_entry(rx->to_be_accepted.next, struct rxrpc_call, accept_link); list_del(&call->accept_link); rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET, rxrpc_abort_call_sock_release_tba); rxrpc_put_call(call, rxrpc_call_put_release_sock_tba); } while (!list_empty(&rx->sock_calls)) { call = list_entry(rx->sock_calls.next, struct rxrpc_call, sock_link); rxrpc_get_call(call, rxrpc_call_get_release_sock); rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET, rxrpc_abort_call_sock_release); rxrpc_release_call(rx, call); rxrpc_put_call(call, rxrpc_call_put_release_sock); } _leave(""); } /* * release a call */ void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why) { struct rxrpc_net *rxnet = call->rxnet; unsigned int debug_id = call->debug_id; bool dead; int r; ASSERT(call != NULL); dead = __refcount_dec_and_test(&call->ref, &r); trace_rxrpc_call(debug_id, r - 1, 0, why); if (dead) { ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE); if (!list_empty(&call->link)) { spin_lock(&rxnet->call_lock); list_del_init(&call->link); spin_unlock(&rxnet->call_lock); } rxrpc_cleanup_call(call); } } /* * Free up the call under RCU. */ static void rxrpc_rcu_free_call(struct rcu_head *rcu) { struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu); struct rxrpc_net *rxnet = READ_ONCE(call->rxnet); kmem_cache_free(rxrpc_call_jar, call); if (atomic_dec_and_test(&rxnet->nr_calls)) wake_up_var(&rxnet->nr_calls); } /* * Final call destruction - but must be done in process context. */ static void rxrpc_destroy_call(struct work_struct *work) { struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer); struct rxrpc_txbuf *txb; del_timer_sync(&call->timer); rxrpc_cleanup_ring(call); while ((txb = list_first_entry_or_null(&call->tx_sendmsg, struct rxrpc_txbuf, call_link))) { list_del(&txb->call_link); rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned); } while ((txb = list_first_entry_or_null(&call->tx_buffer, struct rxrpc_txbuf, call_link))) { list_del(&txb->call_link); rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned); } rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned); rxrpc_put_connection(call->conn, rxrpc_conn_put_call); rxrpc_deactivate_bundle(call->bundle); rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call); rxrpc_put_peer(call->peer, rxrpc_peer_put_call); rxrpc_put_local(call->local, rxrpc_local_put_call); call_rcu(&call->rcu, rxrpc_rcu_free_call); } /* * clean up a call */ void rxrpc_cleanup_call(struct rxrpc_call *call) { memset(&call->sock_node, 0xcd, sizeof(call->sock_node)); ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE); ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags)); del_timer(&call->timer); if (rcu_read_lock_held()) /* Can't use the rxrpc workqueue as we need to cancel/flush * something that may be running/waiting there. */ schedule_work(&call->destroyer); else rxrpc_destroy_call(&call->destroyer); } /* * Make sure that all calls are gone from a network namespace. To reach this * point, any open UDP sockets in that namespace must have been closed, so any * outstanding calls cannot be doing I/O. */ void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet) { struct rxrpc_call *call; _enter(""); if (!list_empty(&rxnet->calls)) { spin_lock(&rxnet->call_lock); while (!list_empty(&rxnet->calls)) { call = list_entry(rxnet->calls.next, struct rxrpc_call, link); _debug("Zapping call %p", call); rxrpc_see_call(call, rxrpc_call_see_zap); list_del_init(&call->link); pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n", call, refcount_read(&call->ref), rxrpc_call_states[__rxrpc_call_state(call)], call->flags, call->events); spin_unlock(&rxnet->call_lock); cond_resched(); spin_lock(&rxnet->call_lock); } spin_unlock(&rxnet->call_lock); } atomic_dec(&rxnet->nr_calls); wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls)); }
linux-master
net/rxrpc/call_object.c
// SPDX-License-Identifier: GPL-2.0-or-later /* Service connection management * * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #include <linux/slab.h> #include "ar-internal.h" /* * Find a service connection under RCU conditions. * * We could use a hash table, but that is subject to bucket stuffing by an * attacker as the client gets to pick the epoch and cid values and would know * the hash function. So, instead, we use a hash table for the peer and from * that an rbtree to find the service connection. Under ordinary circumstances * it might be slower than a large hash table, but it is at least limited in * depth. */ struct rxrpc_connection *rxrpc_find_service_conn_rcu(struct rxrpc_peer *peer, struct sk_buff *skb) { struct rxrpc_connection *conn = NULL; struct rxrpc_conn_proto k; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct rb_node *p; unsigned int seq = 0; k.epoch = sp->hdr.epoch; k.cid = sp->hdr.cid & RXRPC_CIDMASK; do { /* Unfortunately, rbtree walking doesn't give reliable results * under just the RCU read lock, so we have to check for * changes. */ read_seqbegin_or_lock(&peer->service_conn_lock, &seq); p = rcu_dereference_raw(peer->service_conns.rb_node); while (p) { conn = rb_entry(p, struct rxrpc_connection, service_node); if (conn->proto.index_key < k.index_key) p = rcu_dereference_raw(p->rb_left); else if (conn->proto.index_key > k.index_key) p = rcu_dereference_raw(p->rb_right); else break; conn = NULL; } } while (need_seqretry(&peer->service_conn_lock, seq)); done_seqretry(&peer->service_conn_lock, seq); _leave(" = %d", conn ? conn->debug_id : -1); return conn; } /* * Insert a service connection into a peer's tree, thereby making it a target * for incoming packets. */ static void rxrpc_publish_service_conn(struct rxrpc_peer *peer, struct rxrpc_connection *conn) { struct rxrpc_connection *cursor = NULL; struct rxrpc_conn_proto k = conn->proto; struct rb_node **pp, *parent; write_seqlock(&peer->service_conn_lock); pp = &peer->service_conns.rb_node; parent = NULL; while (*pp) { parent = *pp; cursor = rb_entry(parent, struct rxrpc_connection, service_node); if (cursor->proto.index_key < k.index_key) pp = &(*pp)->rb_left; else if (cursor->proto.index_key > k.index_key) pp = &(*pp)->rb_right; else goto found_extant_conn; } rb_link_node_rcu(&conn->service_node, parent, pp); rb_insert_color(&conn->service_node, &peer->service_conns); conn_published: set_bit(RXRPC_CONN_IN_SERVICE_CONNS, &conn->flags); write_sequnlock(&peer->service_conn_lock); _leave(" = %d [new]", conn->debug_id); return; found_extant_conn: if (refcount_read(&cursor->ref) == 0) goto replace_old_connection; write_sequnlock(&peer->service_conn_lock); /* We should not be able to get here. rxrpc_incoming_connection() is * called in a non-reentrant context, so there can't be a race to * insert a new connection. */ BUG(); replace_old_connection: /* The old connection is from an outdated epoch. */ _debug("replace conn"); rb_replace_node_rcu(&cursor->service_node, &conn->service_node, &peer->service_conns); clear_bit(RXRPC_CONN_IN_SERVICE_CONNS, &cursor->flags); goto conn_published; } /* * Preallocate a service connection. The connection is placed on the proc and * reap lists so that we don't have to get the lock from BH context. */ struct rxrpc_connection *rxrpc_prealloc_service_connection(struct rxrpc_net *rxnet, gfp_t gfp) { struct rxrpc_connection *conn = rxrpc_alloc_connection(rxnet, gfp); if (conn) { /* We maintain an extra ref on the connection whilst it is on * the rxrpc_connections list. */ conn->state = RXRPC_CONN_SERVICE_PREALLOC; refcount_set(&conn->ref, 2); atomic_inc(&rxnet->nr_conns); write_lock(&rxnet->conn_lock); list_add_tail(&conn->link, &rxnet->service_conns); list_add_tail(&conn->proc_link, &rxnet->conn_proc_list); write_unlock(&rxnet->conn_lock); rxrpc_see_connection(conn, rxrpc_conn_new_service); } return conn; } /* * Set up an incoming connection. This is called in BH context with the RCU * read lock held. */ void rxrpc_new_incoming_connection(struct rxrpc_sock *rx, struct rxrpc_connection *conn, const struct rxrpc_security *sec, struct sk_buff *skb) { struct rxrpc_skb_priv *sp = rxrpc_skb(skb); _enter(""); conn->proto.epoch = sp->hdr.epoch; conn->proto.cid = sp->hdr.cid & RXRPC_CIDMASK; conn->orig_service_id = sp->hdr.serviceId; conn->service_id = sp->hdr.serviceId; conn->security_ix = sp->hdr.securityIndex; conn->out_clientflag = 0; conn->security = sec; if (conn->security_ix) conn->state = RXRPC_CONN_SERVICE_UNSECURED; else conn->state = RXRPC_CONN_SERVICE; /* See if we should upgrade the service. This can only happen on the * first packet on a new connection. Once done, it applies to all * subsequent calls on that connection. */ if (sp->hdr.userStatus == RXRPC_USERSTATUS_SERVICE_UPGRADE && conn->service_id == rx->service_upgrade.from) conn->service_id = rx->service_upgrade.to; atomic_set(&conn->active, 1); /* Make the connection a target for incoming packets. */ rxrpc_publish_service_conn(conn->peer, conn); } /* * Remove the service connection from the peer's tree, thereby removing it as a * target for incoming packets. */ void rxrpc_unpublish_service_conn(struct rxrpc_connection *conn) { struct rxrpc_peer *peer = conn->peer; write_seqlock(&peer->service_conn_lock); if (test_and_clear_bit(RXRPC_CONN_IN_SERVICE_CONNS, &conn->flags)) rb_erase(&conn->service_node, &peer->service_conns); write_sequnlock(&peer->service_conn_lock); }
linux-master
net/rxrpc/conn_service.c
// SPDX-License-Identifier: GPL-2.0-or-later /* /proc/net/ support for AF_RXRPC * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #include <linux/module.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include "ar-internal.h" static const char *const rxrpc_conn_states[RXRPC_CONN__NR_STATES] = { [RXRPC_CONN_UNUSED] = "Unused ", [RXRPC_CONN_CLIENT_UNSECURED] = "ClUnsec ", [RXRPC_CONN_CLIENT] = "Client ", [RXRPC_CONN_SERVICE_PREALLOC] = "SvPrealc", [RXRPC_CONN_SERVICE_UNSECURED] = "SvUnsec ", [RXRPC_CONN_SERVICE_CHALLENGING] = "SvChall ", [RXRPC_CONN_SERVICE] = "SvSecure", [RXRPC_CONN_ABORTED] = "Aborted ", }; /* * generate a list of extant and dead calls in /proc/net/rxrpc_calls */ static void *rxrpc_call_seq_start(struct seq_file *seq, loff_t *_pos) __acquires(rcu) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); rcu_read_lock(); return seq_list_start_head_rcu(&rxnet->calls, *_pos); } static void *rxrpc_call_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); return seq_list_next_rcu(v, &rxnet->calls, pos); } static void rxrpc_call_seq_stop(struct seq_file *seq, void *v) __releases(rcu) { rcu_read_unlock(); } static int rxrpc_call_seq_show(struct seq_file *seq, void *v) { struct rxrpc_local *local; struct rxrpc_call *call; struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); enum rxrpc_call_state state; unsigned long timeout = 0; rxrpc_seq_t acks_hard_ack; char lbuff[50], rbuff[50]; if (v == &rxnet->calls) { seq_puts(seq, "Proto Local " " Remote " " SvID ConnID CallID End Use State Abort " " DebugId TxSeq TW RxSeq RW RxSerial CW RxTimo\n"); return 0; } call = list_entry(v, struct rxrpc_call, link); local = call->local; if (local) sprintf(lbuff, "%pISpc", &local->srx.transport); else strcpy(lbuff, "no_local"); sprintf(rbuff, "%pISpc", &call->dest_srx.transport); state = rxrpc_call_state(call); if (state != RXRPC_CALL_SERVER_PREALLOC) { timeout = READ_ONCE(call->expect_rx_by); timeout -= jiffies; } acks_hard_ack = READ_ONCE(call->acks_hard_ack); seq_printf(seq, "UDP %-47.47s %-47.47s %4x %08x %08x %s %3u" " %-8.8s %08x %08x %08x %02x %08x %02x %08x %02x %06lx\n", lbuff, rbuff, call->dest_srx.srx_service, call->cid, call->call_id, rxrpc_is_service_call(call) ? "Svc" : "Clt", refcount_read(&call->ref), rxrpc_call_states[state], call->abort_code, call->debug_id, acks_hard_ack, READ_ONCE(call->tx_top) - acks_hard_ack, call->ackr_window, call->ackr_wtop - call->ackr_window, call->rx_serial, call->cong_cwnd, timeout); return 0; } const struct seq_operations rxrpc_call_seq_ops = { .start = rxrpc_call_seq_start, .next = rxrpc_call_seq_next, .stop = rxrpc_call_seq_stop, .show = rxrpc_call_seq_show, }; /* * generate a list of extant virtual connections in /proc/net/rxrpc_conns */ static void *rxrpc_connection_seq_start(struct seq_file *seq, loff_t *_pos) __acquires(rxnet->conn_lock) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); read_lock(&rxnet->conn_lock); return seq_list_start_head(&rxnet->conn_proc_list, *_pos); } static void *rxrpc_connection_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); return seq_list_next(v, &rxnet->conn_proc_list, pos); } static void rxrpc_connection_seq_stop(struct seq_file *seq, void *v) __releases(rxnet->conn_lock) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); read_unlock(&rxnet->conn_lock); } static int rxrpc_connection_seq_show(struct seq_file *seq, void *v) { struct rxrpc_connection *conn; struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); const char *state; char lbuff[50], rbuff[50]; if (v == &rxnet->conn_proc_list) { seq_puts(seq, "Proto Local " " Remote " " SvID ConnID End Ref Act State Key " " Serial ISerial CallId0 CallId1 CallId2 CallId3\n" ); return 0; } conn = list_entry(v, struct rxrpc_connection, proc_link); if (conn->state == RXRPC_CONN_SERVICE_PREALLOC) { strcpy(lbuff, "no_local"); strcpy(rbuff, "no_connection"); goto print; } sprintf(lbuff, "%pISpc", &conn->local->srx.transport); sprintf(rbuff, "%pISpc", &conn->peer->srx.transport); print: state = rxrpc_is_conn_aborted(conn) ? rxrpc_call_completions[conn->completion] : rxrpc_conn_states[conn->state]; seq_printf(seq, "UDP %-47.47s %-47.47s %4x %08x %s %3u %3d" " %s %08x %08x %08x %08x %08x %08x %08x\n", lbuff, rbuff, conn->service_id, conn->proto.cid, rxrpc_conn_is_service(conn) ? "Svc" : "Clt", refcount_read(&conn->ref), atomic_read(&conn->active), state, key_serial(conn->key), atomic_read(&conn->serial), conn->hi_serial, conn->channels[0].call_id, conn->channels[1].call_id, conn->channels[2].call_id, conn->channels[3].call_id); return 0; } const struct seq_operations rxrpc_connection_seq_ops = { .start = rxrpc_connection_seq_start, .next = rxrpc_connection_seq_next, .stop = rxrpc_connection_seq_stop, .show = rxrpc_connection_seq_show, }; /* * generate a list of extant virtual peers in /proc/net/rxrpc/peers */ static int rxrpc_peer_seq_show(struct seq_file *seq, void *v) { struct rxrpc_peer *peer; time64_t now; char lbuff[50], rbuff[50]; if (v == SEQ_START_TOKEN) { seq_puts(seq, "Proto Local " " Remote " " Use SST MTU LastUse RTT RTO\n" ); return 0; } peer = list_entry(v, struct rxrpc_peer, hash_link); sprintf(lbuff, "%pISpc", &peer->local->srx.transport); sprintf(rbuff, "%pISpc", &peer->srx.transport); now = ktime_get_seconds(); seq_printf(seq, "UDP %-47.47s %-47.47s %3u" " %3u %5u %6llus %8u %8u\n", lbuff, rbuff, refcount_read(&peer->ref), peer->cong_ssthresh, peer->mtu, now - peer->last_tx_at, peer->srtt_us >> 3, jiffies_to_usecs(peer->rto_j)); return 0; } static void *rxrpc_peer_seq_start(struct seq_file *seq, loff_t *_pos) __acquires(rcu) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); unsigned int bucket, n; unsigned int shift = 32 - HASH_BITS(rxnet->peer_hash); void *p; rcu_read_lock(); if (*_pos >= UINT_MAX) return NULL; n = *_pos & ((1U << shift) - 1); bucket = *_pos >> shift; for (;;) { if (bucket >= HASH_SIZE(rxnet->peer_hash)) { *_pos = UINT_MAX; return NULL; } if (n == 0) { if (bucket == 0) return SEQ_START_TOKEN; *_pos += 1; n++; } p = seq_hlist_start_rcu(&rxnet->peer_hash[bucket], n - 1); if (p) return p; bucket++; n = 1; *_pos = (bucket << shift) | n; } } static void *rxrpc_peer_seq_next(struct seq_file *seq, void *v, loff_t *_pos) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); unsigned int bucket, n; unsigned int shift = 32 - HASH_BITS(rxnet->peer_hash); void *p; if (*_pos >= UINT_MAX) return NULL; bucket = *_pos >> shift; p = seq_hlist_next_rcu(v, &rxnet->peer_hash[bucket], _pos); if (p) return p; for (;;) { bucket++; n = 1; *_pos = (bucket << shift) | n; if (bucket >= HASH_SIZE(rxnet->peer_hash)) { *_pos = UINT_MAX; return NULL; } if (n == 0) { *_pos += 1; n++; } p = seq_hlist_start_rcu(&rxnet->peer_hash[bucket], n - 1); if (p) return p; } } static void rxrpc_peer_seq_stop(struct seq_file *seq, void *v) __releases(rcu) { rcu_read_unlock(); } const struct seq_operations rxrpc_peer_seq_ops = { .start = rxrpc_peer_seq_start, .next = rxrpc_peer_seq_next, .stop = rxrpc_peer_seq_stop, .show = rxrpc_peer_seq_show, }; /* * Generate a list of extant virtual local endpoints in /proc/net/rxrpc/locals */ static int rxrpc_local_seq_show(struct seq_file *seq, void *v) { struct rxrpc_local *local; char lbuff[50]; if (v == SEQ_START_TOKEN) { seq_puts(seq, "Proto Local " " Use Act RxQ\n"); return 0; } local = hlist_entry(v, struct rxrpc_local, link); sprintf(lbuff, "%pISpc", &local->srx.transport); seq_printf(seq, "UDP %-47.47s %3u %3u %3u\n", lbuff, refcount_read(&local->ref), atomic_read(&local->active_users), local->rx_queue.qlen); return 0; } static void *rxrpc_local_seq_start(struct seq_file *seq, loff_t *_pos) __acquires(rcu) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); unsigned int n; rcu_read_lock(); if (*_pos >= UINT_MAX) return NULL; n = *_pos; if (n == 0) return SEQ_START_TOKEN; return seq_hlist_start_rcu(&rxnet->local_endpoints, n - 1); } static void *rxrpc_local_seq_next(struct seq_file *seq, void *v, loff_t *_pos) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq)); if (*_pos >= UINT_MAX) return NULL; return seq_hlist_next_rcu(v, &rxnet->local_endpoints, _pos); } static void rxrpc_local_seq_stop(struct seq_file *seq, void *v) __releases(rcu) { rcu_read_unlock(); } const struct seq_operations rxrpc_local_seq_ops = { .start = rxrpc_local_seq_start, .next = rxrpc_local_seq_next, .stop = rxrpc_local_seq_stop, .show = rxrpc_local_seq_show, }; /* * Display stats in /proc/net/rxrpc/stats */ int rxrpc_stats_show(struct seq_file *seq, void *v) { struct rxrpc_net *rxnet = rxrpc_net(seq_file_single_net(seq)); seq_printf(seq, "Data : send=%u sendf=%u fail=%u\n", atomic_read(&rxnet->stat_tx_data_send), atomic_read(&rxnet->stat_tx_data_send_frag), atomic_read(&rxnet->stat_tx_data_send_fail)); seq_printf(seq, "Data-Tx : nr=%u retrans=%u uf=%u cwr=%u\n", atomic_read(&rxnet->stat_tx_data), atomic_read(&rxnet->stat_tx_data_retrans), atomic_read(&rxnet->stat_tx_data_underflow), atomic_read(&rxnet->stat_tx_data_cwnd_reset)); seq_printf(seq, "Data-Rx : nr=%u reqack=%u jumbo=%u\n", atomic_read(&rxnet->stat_rx_data), atomic_read(&rxnet->stat_rx_data_reqack), atomic_read(&rxnet->stat_rx_data_jumbo)); seq_printf(seq, "Ack : fill=%u send=%u skip=%u\n", atomic_read(&rxnet->stat_tx_ack_fill), atomic_read(&rxnet->stat_tx_ack_send), atomic_read(&rxnet->stat_tx_ack_skip)); seq_printf(seq, "Ack-Tx : req=%u dup=%u oos=%u exw=%u nos=%u png=%u prs=%u dly=%u idl=%u\n", atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_REQUESTED]), atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_DUPLICATE]), atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_OUT_OF_SEQUENCE]), atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_EXCEEDS_WINDOW]), atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_NOSPACE]), atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_PING]), atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_PING_RESPONSE]), atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_DELAY]), atomic_read(&rxnet->stat_tx_acks[RXRPC_ACK_IDLE])); seq_printf(seq, "Ack-Rx : req=%u dup=%u oos=%u exw=%u nos=%u png=%u prs=%u dly=%u idl=%u\n", atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_REQUESTED]), atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_DUPLICATE]), atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_OUT_OF_SEQUENCE]), atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_EXCEEDS_WINDOW]), atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_NOSPACE]), atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_PING]), atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_PING_RESPONSE]), atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_DELAY]), atomic_read(&rxnet->stat_rx_acks[RXRPC_ACK_IDLE])); seq_printf(seq, "Why-Req-A: acklost=%u already=%u mrtt=%u ortt=%u\n", atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_ack_lost]), atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_already_on]), atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_more_rtt]), atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_old_rtt])); seq_printf(seq, "Why-Req-A: nolast=%u retx=%u slows=%u smtxw=%u\n", atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_no_srv_last]), atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_retrans]), atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_slow_start]), atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_small_txwin])); seq_printf(seq, "Buffers : txb=%u rxb=%u\n", atomic_read(&rxrpc_nr_txbuf), atomic_read(&rxrpc_n_rx_skbs)); seq_printf(seq, "IO-thread: loops=%u\n", atomic_read(&rxnet->stat_io_loop)); return 0; } /* * Clear stats if /proc/net/rxrpc/stats is written to. */ int rxrpc_stats_clear(struct file *file, char *buf, size_t size) { struct seq_file *m = file->private_data; struct rxrpc_net *rxnet = rxrpc_net(seq_file_single_net(m)); if (size > 1 || (size == 1 && buf[0] != '\n')) return -EINVAL; atomic_set(&rxnet->stat_tx_data, 0); atomic_set(&rxnet->stat_tx_data_retrans, 0); atomic_set(&rxnet->stat_tx_data_underflow, 0); atomic_set(&rxnet->stat_tx_data_cwnd_reset, 0); atomic_set(&rxnet->stat_tx_data_send, 0); atomic_set(&rxnet->stat_tx_data_send_frag, 0); atomic_set(&rxnet->stat_tx_data_send_fail, 0); atomic_set(&rxnet->stat_rx_data, 0); atomic_set(&rxnet->stat_rx_data_reqack, 0); atomic_set(&rxnet->stat_rx_data_jumbo, 0); atomic_set(&rxnet->stat_tx_ack_fill, 0); atomic_set(&rxnet->stat_tx_ack_send, 0); atomic_set(&rxnet->stat_tx_ack_skip, 0); memset(&rxnet->stat_tx_acks, 0, sizeof(rxnet->stat_tx_acks)); memset(&rxnet->stat_rx_acks, 0, sizeof(rxnet->stat_rx_acks)); memset(&rxnet->stat_why_req_ack, 0, sizeof(rxnet->stat_why_req_ack)); atomic_set(&rxnet->stat_io_loop, 0); return size; }
linux-master
net/rxrpc/proc.c
// SPDX-License-Identifier: GPL-2.0-or-later /* Call state changing functions. * * Copyright (C) 2022 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #include "ar-internal.h" /* * Transition a call to the complete state. */ bool rxrpc_set_call_completion(struct rxrpc_call *call, enum rxrpc_call_completion compl, u32 abort_code, int error) { if (__rxrpc_call_state(call) == RXRPC_CALL_COMPLETE) return false; call->abort_code = abort_code; call->error = error; call->completion = compl; /* Allow reader of completion state to operate locklessly */ rxrpc_set_call_state(call, RXRPC_CALL_COMPLETE); trace_rxrpc_call_complete(call); wake_up(&call->waitq); rxrpc_notify_socket(call); return true; } /* * Record that a call successfully completed. */ bool rxrpc_call_completed(struct rxrpc_call *call) { return rxrpc_set_call_completion(call, RXRPC_CALL_SUCCEEDED, 0, 0); } /* * Record that a call is locally aborted. */ bool rxrpc_abort_call(struct rxrpc_call *call, rxrpc_seq_t seq, u32 abort_code, int error, enum rxrpc_abort_reason why) { trace_rxrpc_abort(call->debug_id, why, call->cid, call->call_id, seq, abort_code, error); if (!rxrpc_set_call_completion(call, RXRPC_CALL_LOCALLY_ABORTED, abort_code, error)) return false; if (test_bit(RXRPC_CALL_EXPOSED, &call->flags)) rxrpc_send_abort_packet(call); return true; } /* * Record that a call errored out before even getting off the ground, thereby * setting the state to allow it to be destroyed. */ void rxrpc_prefail_call(struct rxrpc_call *call, enum rxrpc_call_completion compl, int error) { call->abort_code = RX_CALL_DEAD; call->error = error; call->completion = compl; call->_state = RXRPC_CALL_COMPLETE; trace_rxrpc_call_complete(call); WARN_ON_ONCE(__test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags)); }
linux-master
net/rxrpc/call_state.c
// SPDX-License-Identifier: GPL-2.0 /* RTT/RTO calculation. * * Adapted from TCP for AF_RXRPC by David Howells ([email protected]) * * https://tools.ietf.org/html/rfc6298 * https://tools.ietf.org/html/rfc1122#section-4.2.3.1 * http://ccr.sigcomm.org/archive/1995/jan95/ccr-9501-partridge87.pdf */ #include <linux/net.h> #include "ar-internal.h" #define RXRPC_RTO_MAX ((unsigned)(120 * HZ)) #define RXRPC_TIMEOUT_INIT ((unsigned)(1*HZ)) /* RFC6298 2.1 initial RTO value */ #define rxrpc_jiffies32 ((u32)jiffies) /* As rxrpc_jiffies32 */ static u32 rxrpc_rto_min_us(struct rxrpc_peer *peer) { return 200; } static u32 __rxrpc_set_rto(const struct rxrpc_peer *peer) { return usecs_to_jiffies((peer->srtt_us >> 3) + peer->rttvar_us); } static u32 rxrpc_bound_rto(u32 rto) { return min(rto, RXRPC_RTO_MAX); } /* * Called to compute a smoothed rtt estimate. The data fed to this * routine either comes from timestamps, or from segments that were * known _not_ to have been retransmitted [see Karn/Partridge * Proceedings SIGCOMM 87]. The algorithm is from the SIGCOMM 88 * piece by Van Jacobson. * NOTE: the next three routines used to be one big routine. * To save cycles in the RFC 1323 implementation it was better to break * it up into three procedures. -- erics */ static void rxrpc_rtt_estimator(struct rxrpc_peer *peer, long sample_rtt_us) { long m = sample_rtt_us; /* RTT */ u32 srtt = peer->srtt_us; /* The following amusing code comes from Jacobson's * article in SIGCOMM '88. Note that rtt and mdev * are scaled versions of rtt and mean deviation. * This is designed to be as fast as possible * m stands for "measurement". * * On a 1990 paper the rto value is changed to: * RTO = rtt + 4 * mdev * * Funny. This algorithm seems to be very broken. * These formulae increase RTO, when it should be decreased, increase * too slowly, when it should be increased quickly, decrease too quickly * etc. I guess in BSD RTO takes ONE value, so that it is absolutely * does not matter how to _calculate_ it. Seems, it was trap * that VJ failed to avoid. 8) */ if (srtt != 0) { m -= (srtt >> 3); /* m is now error in rtt est */ srtt += m; /* rtt = 7/8 rtt + 1/8 new */ if (m < 0) { m = -m; /* m is now abs(error) */ m -= (peer->mdev_us >> 2); /* similar update on mdev */ /* This is similar to one of Eifel findings. * Eifel blocks mdev updates when rtt decreases. * This solution is a bit different: we use finer gain * for mdev in this case (alpha*beta). * Like Eifel it also prevents growth of rto, * but also it limits too fast rto decreases, * happening in pure Eifel. */ if (m > 0) m >>= 3; } else { m -= (peer->mdev_us >> 2); /* similar update on mdev */ } peer->mdev_us += m; /* mdev = 3/4 mdev + 1/4 new */ if (peer->mdev_us > peer->mdev_max_us) { peer->mdev_max_us = peer->mdev_us; if (peer->mdev_max_us > peer->rttvar_us) peer->rttvar_us = peer->mdev_max_us; } } else { /* no previous measure. */ srtt = m << 3; /* take the measured time to be rtt */ peer->mdev_us = m << 1; /* make sure rto = 3*rtt */ peer->rttvar_us = max(peer->mdev_us, rxrpc_rto_min_us(peer)); peer->mdev_max_us = peer->rttvar_us; } peer->srtt_us = max(1U, srtt); } /* * Calculate rto without backoff. This is the second half of Van Jacobson's * routine referred to above. */ static void rxrpc_set_rto(struct rxrpc_peer *peer) { u32 rto; /* 1. If rtt variance happened to be less 50msec, it is hallucination. * It cannot be less due to utterly erratic ACK generation made * at least by solaris and freebsd. "Erratic ACKs" has _nothing_ * to do with delayed acks, because at cwnd>2 true delack timeout * is invisible. Actually, Linux-2.4 also generates erratic * ACKs in some circumstances. */ rto = __rxrpc_set_rto(peer); /* 2. Fixups made earlier cannot be right. * If we do not estimate RTO correctly without them, * all the algo is pure shit and should be replaced * with correct one. It is exactly, which we pretend to do. */ /* NOTE: clamping at RXRPC_RTO_MIN is not required, current algo * guarantees that rto is higher. */ peer->rto_j = rxrpc_bound_rto(rto); } static void rxrpc_ack_update_rtt(struct rxrpc_peer *peer, long rtt_us) { if (rtt_us < 0) return; //rxrpc_update_rtt_min(peer, rtt_us); rxrpc_rtt_estimator(peer, rtt_us); rxrpc_set_rto(peer); /* RFC6298: only reset backoff on valid RTT measurement. */ peer->backoff = 0; } /* * Add RTT information to cache. This is called in softirq mode and has * exclusive access to the peer RTT data. */ void rxrpc_peer_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why, int rtt_slot, rxrpc_serial_t send_serial, rxrpc_serial_t resp_serial, ktime_t send_time, ktime_t resp_time) { struct rxrpc_peer *peer = call->peer; s64 rtt_us; rtt_us = ktime_to_us(ktime_sub(resp_time, send_time)); if (rtt_us < 0) return; spin_lock(&peer->rtt_input_lock); rxrpc_ack_update_rtt(peer, rtt_us); if (peer->rtt_count < 3) peer->rtt_count++; spin_unlock(&peer->rtt_input_lock); trace_rxrpc_rtt_rx(call, why, rtt_slot, send_serial, resp_serial, peer->srtt_us >> 3, peer->rto_j); } /* * Get the retransmission timeout to set in jiffies, backing it off each time * we retransmit. */ unsigned long rxrpc_get_rto_backoff(struct rxrpc_peer *peer, bool retrans) { u64 timo_j; u8 backoff = READ_ONCE(peer->backoff); timo_j = peer->rto_j; timo_j <<= backoff; if (retrans && timo_j * 2 <= RXRPC_RTO_MAX) WRITE_ONCE(peer->backoff, backoff + 1); if (timo_j < 1) timo_j = 1; return timo_j; } void rxrpc_peer_init_rtt(struct rxrpc_peer *peer) { peer->rto_j = RXRPC_TIMEOUT_INIT; peer->mdev_us = jiffies_to_usecs(RXRPC_TIMEOUT_INIT); peer->backoff = 0; //minmax_reset(&peer->rtt_min, rxrpc_jiffies32, ~0U); }
linux-master
net/rxrpc/rtt.c
// SPDX-License-Identifier: GPL-2.0-or-later /* AF_RXRPC local endpoint management * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.h> #include <linux/net.h> #include <linux/skbuff.h> #include <linux/slab.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include <generated/utsrelease.h> #include "ar-internal.h" static char rxrpc_version_string[65]; // "linux-" UTS_RELEASE " AF_RXRPC"; /* * Generate the VERSION packet string. */ void rxrpc_gen_version_string(void) { snprintf(rxrpc_version_string, sizeof(rxrpc_version_string), "linux-%.49s AF_RXRPC", UTS_RELEASE); } /* * Reply to a version request */ void rxrpc_send_version_request(struct rxrpc_local *local, struct rxrpc_host_header *hdr, struct sk_buff *skb) { struct rxrpc_wire_header whdr; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct sockaddr_rxrpc srx; struct msghdr msg; struct kvec iov[2]; size_t len; int ret; _enter(""); if (rxrpc_extract_addr_from_skb(&srx, skb) < 0) return; msg.msg_name = &srx.transport; msg.msg_namelen = srx.transport_len; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; whdr.epoch = htonl(sp->hdr.epoch); whdr.cid = htonl(sp->hdr.cid); whdr.callNumber = htonl(sp->hdr.callNumber); whdr.seq = 0; whdr.serial = 0; whdr.type = RXRPC_PACKET_TYPE_VERSION; whdr.flags = RXRPC_LAST_PACKET | (~hdr->flags & RXRPC_CLIENT_INITIATED); whdr.userStatus = 0; whdr.securityIndex = 0; whdr._rsvd = 0; whdr.serviceId = htons(sp->hdr.serviceId); iov[0].iov_base = &whdr; iov[0].iov_len = sizeof(whdr); iov[1].iov_base = (char *)rxrpc_version_string; iov[1].iov_len = sizeof(rxrpc_version_string); len = iov[0].iov_len + iov[1].iov_len; ret = kernel_sendmsg(local->socket, &msg, iov, 2, len); if (ret < 0) trace_rxrpc_tx_fail(local->debug_id, 0, ret, rxrpc_tx_point_version_reply); else trace_rxrpc_tx_packet(local->debug_id, &whdr, rxrpc_tx_point_version_reply); _leave(""); }
linux-master
net/rxrpc/local_event.c
// SPDX-License-Identifier: GPL-2.0-or-later /* Client connection-specific management code. * * Copyright (C) 2016, 2020 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) * * Client connections need to be cached for a little while after they've made a * call so as to handle retransmitted DATA packets in case the server didn't * receive the final ACK or terminating ABORT we sent it. * * There are flags of relevance to the cache: * * (2) DONT_REUSE - The connection should be discarded as soon as possible and * should not be reused. This is set when an exclusive connection is used * or a call ID counter overflows. * * The caching state may only be changed if the cache lock is held. * * There are two idle client connection expiry durations. If the total number * of connections is below the reap threshold, we use the normal duration; if * it's above, we use the fast duration. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/slab.h> #include <linux/idr.h> #include <linux/timer.h> #include <linux/sched/signal.h> #include "ar-internal.h" __read_mostly unsigned int rxrpc_reap_client_connections = 900; __read_mostly unsigned long rxrpc_conn_idle_client_expiry = 2 * 60 * HZ; __read_mostly unsigned long rxrpc_conn_idle_client_fast_expiry = 2 * HZ; static void rxrpc_activate_bundle(struct rxrpc_bundle *bundle) { atomic_inc(&bundle->active); } /* * Release a connection ID for a client connection. */ static void rxrpc_put_client_connection_id(struct rxrpc_local *local, struct rxrpc_connection *conn) { idr_remove(&local->conn_ids, conn->proto.cid >> RXRPC_CIDSHIFT); } /* * Destroy the client connection ID tree. */ static void rxrpc_destroy_client_conn_ids(struct rxrpc_local *local) { struct rxrpc_connection *conn; int id; if (!idr_is_empty(&local->conn_ids)) { idr_for_each_entry(&local->conn_ids, conn, id) { pr_err("AF_RXRPC: Leaked client conn %p {%d}\n", conn, refcount_read(&conn->ref)); } BUG(); } idr_destroy(&local->conn_ids); } /* * Allocate a connection bundle. */ static struct rxrpc_bundle *rxrpc_alloc_bundle(struct rxrpc_call *call, gfp_t gfp) { struct rxrpc_bundle *bundle; bundle = kzalloc(sizeof(*bundle), gfp); if (bundle) { bundle->local = call->local; bundle->peer = rxrpc_get_peer(call->peer, rxrpc_peer_get_bundle); bundle->key = key_get(call->key); bundle->security = call->security; bundle->exclusive = test_bit(RXRPC_CALL_EXCLUSIVE, &call->flags); bundle->upgrade = test_bit(RXRPC_CALL_UPGRADE, &call->flags); bundle->service_id = call->dest_srx.srx_service; bundle->security_level = call->security_level; refcount_set(&bundle->ref, 1); atomic_set(&bundle->active, 1); INIT_LIST_HEAD(&bundle->waiting_calls); trace_rxrpc_bundle(bundle->debug_id, 1, rxrpc_bundle_new); } return bundle; } struct rxrpc_bundle *rxrpc_get_bundle(struct rxrpc_bundle *bundle, enum rxrpc_bundle_trace why) { int r; __refcount_inc(&bundle->ref, &r); trace_rxrpc_bundle(bundle->debug_id, r + 1, why); return bundle; } static void rxrpc_free_bundle(struct rxrpc_bundle *bundle) { trace_rxrpc_bundle(bundle->debug_id, 1, rxrpc_bundle_free); rxrpc_put_peer(bundle->peer, rxrpc_peer_put_bundle); key_put(bundle->key); kfree(bundle); } void rxrpc_put_bundle(struct rxrpc_bundle *bundle, enum rxrpc_bundle_trace why) { unsigned int id; bool dead; int r; if (bundle) { id = bundle->debug_id; dead = __refcount_dec_and_test(&bundle->ref, &r); trace_rxrpc_bundle(id, r - 1, why); if (dead) rxrpc_free_bundle(bundle); } } /* * Get rid of outstanding client connection preallocations when a local * endpoint is destroyed. */ void rxrpc_purge_client_connections(struct rxrpc_local *local) { rxrpc_destroy_client_conn_ids(local); } /* * Allocate a client connection. */ static struct rxrpc_connection * rxrpc_alloc_client_connection(struct rxrpc_bundle *bundle) { struct rxrpc_connection *conn; struct rxrpc_local *local = bundle->local; struct rxrpc_net *rxnet = local->rxnet; int id; _enter(""); conn = rxrpc_alloc_connection(rxnet, GFP_ATOMIC | __GFP_NOWARN); if (!conn) return ERR_PTR(-ENOMEM); id = idr_alloc_cyclic(&local->conn_ids, conn, 1, 0x40000000, GFP_ATOMIC | __GFP_NOWARN); if (id < 0) { kfree(conn); return ERR_PTR(id); } refcount_set(&conn->ref, 1); conn->proto.cid = id << RXRPC_CIDSHIFT; conn->proto.epoch = local->rxnet->epoch; conn->out_clientflag = RXRPC_CLIENT_INITIATED; conn->bundle = rxrpc_get_bundle(bundle, rxrpc_bundle_get_client_conn); conn->local = rxrpc_get_local(bundle->local, rxrpc_local_get_client_conn); conn->peer = rxrpc_get_peer(bundle->peer, rxrpc_peer_get_client_conn); conn->key = key_get(bundle->key); conn->security = bundle->security; conn->exclusive = bundle->exclusive; conn->upgrade = bundle->upgrade; conn->orig_service_id = bundle->service_id; conn->security_level = bundle->security_level; conn->state = RXRPC_CONN_CLIENT_UNSECURED; conn->service_id = conn->orig_service_id; if (conn->security == &rxrpc_no_security) conn->state = RXRPC_CONN_CLIENT; atomic_inc(&rxnet->nr_conns); write_lock(&rxnet->conn_lock); list_add_tail(&conn->proc_link, &rxnet->conn_proc_list); write_unlock(&rxnet->conn_lock); rxrpc_see_connection(conn, rxrpc_conn_new_client); atomic_inc(&rxnet->nr_client_conns); trace_rxrpc_client(conn, -1, rxrpc_client_alloc); return conn; } /* * Determine if a connection may be reused. */ static bool rxrpc_may_reuse_conn(struct rxrpc_connection *conn) { struct rxrpc_net *rxnet; int id_cursor, id, distance, limit; if (!conn) goto dont_reuse; rxnet = conn->rxnet; if (test_bit(RXRPC_CONN_DONT_REUSE, &conn->flags)) goto dont_reuse; if ((conn->state != RXRPC_CONN_CLIENT_UNSECURED && conn->state != RXRPC_CONN_CLIENT) || conn->proto.epoch != rxnet->epoch) goto mark_dont_reuse; /* The IDR tree gets very expensive on memory if the connection IDs are * widely scattered throughout the number space, so we shall want to * kill off connections that, say, have an ID more than about four * times the maximum number of client conns away from the current * allocation point to try and keep the IDs concentrated. */ id_cursor = idr_get_cursor(&conn->local->conn_ids); id = conn->proto.cid >> RXRPC_CIDSHIFT; distance = id - id_cursor; if (distance < 0) distance = -distance; limit = max_t(unsigned long, atomic_read(&rxnet->nr_conns) * 4, 1024); if (distance > limit) goto mark_dont_reuse; return true; mark_dont_reuse: set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags); dont_reuse: return false; } /* * Look up the conn bundle that matches the connection parameters, adding it if * it doesn't yet exist. */ int rxrpc_look_up_bundle(struct rxrpc_call *call, gfp_t gfp) { static atomic_t rxrpc_bundle_id; struct rxrpc_bundle *bundle, *candidate; struct rxrpc_local *local = call->local; struct rb_node *p, **pp, *parent; long diff; bool upgrade = test_bit(RXRPC_CALL_UPGRADE, &call->flags); _enter("{%px,%x,%u,%u}", call->peer, key_serial(call->key), call->security_level, upgrade); if (test_bit(RXRPC_CALL_EXCLUSIVE, &call->flags)) { call->bundle = rxrpc_alloc_bundle(call, gfp); return call->bundle ? 0 : -ENOMEM; } /* First, see if the bundle is already there. */ _debug("search 1"); spin_lock(&local->client_bundles_lock); p = local->client_bundles.rb_node; while (p) { bundle = rb_entry(p, struct rxrpc_bundle, local_node); #define cmp(X, Y) ((long)(X) - (long)(Y)) diff = (cmp(bundle->peer, call->peer) ?: cmp(bundle->key, call->key) ?: cmp(bundle->security_level, call->security_level) ?: cmp(bundle->upgrade, upgrade)); #undef cmp if (diff < 0) p = p->rb_left; else if (diff > 0) p = p->rb_right; else goto found_bundle; } spin_unlock(&local->client_bundles_lock); _debug("not found"); /* It wasn't. We need to add one. */ candidate = rxrpc_alloc_bundle(call, gfp); if (!candidate) return -ENOMEM; _debug("search 2"); spin_lock(&local->client_bundles_lock); pp = &local->client_bundles.rb_node; parent = NULL; while (*pp) { parent = *pp; bundle = rb_entry(parent, struct rxrpc_bundle, local_node); #define cmp(X, Y) ((long)(X) - (long)(Y)) diff = (cmp(bundle->peer, call->peer) ?: cmp(bundle->key, call->key) ?: cmp(bundle->security_level, call->security_level) ?: cmp(bundle->upgrade, upgrade)); #undef cmp if (diff < 0) pp = &(*pp)->rb_left; else if (diff > 0) pp = &(*pp)->rb_right; else goto found_bundle_free; } _debug("new bundle"); candidate->debug_id = atomic_inc_return(&rxrpc_bundle_id); rb_link_node(&candidate->local_node, parent, pp); rb_insert_color(&candidate->local_node, &local->client_bundles); call->bundle = rxrpc_get_bundle(candidate, rxrpc_bundle_get_client_call); spin_unlock(&local->client_bundles_lock); _leave(" = B=%u [new]", call->bundle->debug_id); return 0; found_bundle_free: rxrpc_free_bundle(candidate); found_bundle: call->bundle = rxrpc_get_bundle(bundle, rxrpc_bundle_get_client_call); rxrpc_activate_bundle(bundle); spin_unlock(&local->client_bundles_lock); _leave(" = B=%u [found]", call->bundle->debug_id); return 0; } /* * Allocate a new connection and add it into a bundle. */ static bool rxrpc_add_conn_to_bundle(struct rxrpc_bundle *bundle, unsigned int slot) { struct rxrpc_connection *conn, *old; unsigned int shift = slot * RXRPC_MAXCALLS; unsigned int i; old = bundle->conns[slot]; if (old) { bundle->conns[slot] = NULL; trace_rxrpc_client(old, -1, rxrpc_client_replace); rxrpc_put_connection(old, rxrpc_conn_put_noreuse); } conn = rxrpc_alloc_client_connection(bundle); if (IS_ERR(conn)) { bundle->alloc_error = PTR_ERR(conn); return false; } rxrpc_activate_bundle(bundle); conn->bundle_shift = shift; bundle->conns[slot] = conn; for (i = 0; i < RXRPC_MAXCALLS; i++) set_bit(shift + i, &bundle->avail_chans); return true; } /* * Add a connection to a bundle if there are no usable connections or we have * connections waiting for extra capacity. */ static bool rxrpc_bundle_has_space(struct rxrpc_bundle *bundle) { int slot = -1, i, usable; _enter(""); bundle->alloc_error = 0; /* See if there are any usable connections. */ usable = 0; for (i = 0; i < ARRAY_SIZE(bundle->conns); i++) { if (rxrpc_may_reuse_conn(bundle->conns[i])) usable++; else if (slot == -1) slot = i; } if (!usable && bundle->upgrade) bundle->try_upgrade = true; if (!usable) goto alloc_conn; if (!bundle->avail_chans && !bundle->try_upgrade && usable < ARRAY_SIZE(bundle->conns)) goto alloc_conn; _leave(""); return usable; alloc_conn: return slot >= 0 ? rxrpc_add_conn_to_bundle(bundle, slot) : false; } /* * Assign a channel to the call at the front of the queue and wake the call up. * We don't increment the callNumber counter until this number has been exposed * to the world. */ static void rxrpc_activate_one_channel(struct rxrpc_connection *conn, unsigned int channel) { struct rxrpc_channel *chan = &conn->channels[channel]; struct rxrpc_bundle *bundle = conn->bundle; struct rxrpc_call *call = list_entry(bundle->waiting_calls.next, struct rxrpc_call, wait_link); u32 call_id = chan->call_counter + 1; _enter("C=%x,%u", conn->debug_id, channel); list_del_init(&call->wait_link); trace_rxrpc_client(conn, channel, rxrpc_client_chan_activate); /* Cancel the final ACK on the previous call if it hasn't been sent yet * as the DATA packet will implicitly ACK it. */ clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags); clear_bit(conn->bundle_shift + channel, &bundle->avail_chans); rxrpc_see_call(call, rxrpc_call_see_activate_client); call->conn = rxrpc_get_connection(conn, rxrpc_conn_get_activate_call); call->cid = conn->proto.cid | channel; call->call_id = call_id; call->dest_srx.srx_service = conn->service_id; call->cong_ssthresh = call->peer->cong_ssthresh; if (call->cong_cwnd >= call->cong_ssthresh) call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE; else call->cong_mode = RXRPC_CALL_SLOW_START; chan->call_id = call_id; chan->call_debug_id = call->debug_id; chan->call = call; rxrpc_see_call(call, rxrpc_call_see_connected); trace_rxrpc_connect_call(call); call->tx_last_sent = ktime_get_real(); rxrpc_start_call_timer(call); rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_SEND_REQUEST); wake_up(&call->waitq); } /* * Remove a connection from the idle list if it's on it. */ static void rxrpc_unidle_conn(struct rxrpc_connection *conn) { if (!list_empty(&conn->cache_link)) { list_del_init(&conn->cache_link); rxrpc_put_connection(conn, rxrpc_conn_put_unidle); } } /* * Assign channels and callNumbers to waiting calls. */ static void rxrpc_activate_channels(struct rxrpc_bundle *bundle) { struct rxrpc_connection *conn; unsigned long avail, mask; unsigned int channel, slot; trace_rxrpc_client(NULL, -1, rxrpc_client_activate_chans); if (bundle->try_upgrade) mask = 1; else mask = ULONG_MAX; while (!list_empty(&bundle->waiting_calls)) { avail = bundle->avail_chans & mask; if (!avail) break; channel = __ffs(avail); clear_bit(channel, &bundle->avail_chans); slot = channel / RXRPC_MAXCALLS; conn = bundle->conns[slot]; if (!conn) break; if (bundle->try_upgrade) set_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags); rxrpc_unidle_conn(conn); channel &= (RXRPC_MAXCALLS - 1); conn->act_chans |= 1 << channel; rxrpc_activate_one_channel(conn, channel); } } /* * Connect waiting channels (called from the I/O thread). */ void rxrpc_connect_client_calls(struct rxrpc_local *local) { struct rxrpc_call *call; while ((call = list_first_entry_or_null(&local->new_client_calls, struct rxrpc_call, wait_link)) ) { struct rxrpc_bundle *bundle = call->bundle; spin_lock(&local->client_call_lock); list_move_tail(&call->wait_link, &bundle->waiting_calls); spin_unlock(&local->client_call_lock); if (rxrpc_bundle_has_space(bundle)) rxrpc_activate_channels(bundle); } } /* * Note that a call, and thus a connection, is about to be exposed to the * world. */ void rxrpc_expose_client_call(struct rxrpc_call *call) { unsigned int channel = call->cid & RXRPC_CHANNELMASK; struct rxrpc_connection *conn = call->conn; struct rxrpc_channel *chan = &conn->channels[channel]; if (!test_and_set_bit(RXRPC_CALL_EXPOSED, &call->flags)) { /* Mark the call ID as being used. If the callNumber counter * exceeds ~2 billion, we kill the connection after its * outstanding calls have finished so that the counter doesn't * wrap. */ chan->call_counter++; if (chan->call_counter >= INT_MAX) set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags); trace_rxrpc_client(conn, channel, rxrpc_client_exposed); spin_lock(&call->peer->lock); hlist_add_head(&call->error_link, &call->peer->error_targets); spin_unlock(&call->peer->lock); } } /* * Set the reap timer. */ static void rxrpc_set_client_reap_timer(struct rxrpc_local *local) { if (!local->kill_all_client_conns) { unsigned long now = jiffies; unsigned long reap_at = now + rxrpc_conn_idle_client_expiry; if (local->rxnet->live) timer_reduce(&local->client_conn_reap_timer, reap_at); } } /* * Disconnect a client call. */ void rxrpc_disconnect_client_call(struct rxrpc_bundle *bundle, struct rxrpc_call *call) { struct rxrpc_connection *conn; struct rxrpc_channel *chan = NULL; struct rxrpc_local *local = bundle->local; unsigned int channel; bool may_reuse; u32 cid; _enter("c=%x", call->debug_id); /* Calls that have never actually been assigned a channel can simply be * discarded. */ conn = call->conn; if (!conn) { _debug("call is waiting"); ASSERTCMP(call->call_id, ==, 0); ASSERT(!test_bit(RXRPC_CALL_EXPOSED, &call->flags)); list_del_init(&call->wait_link); return; } cid = call->cid; channel = cid & RXRPC_CHANNELMASK; chan = &conn->channels[channel]; trace_rxrpc_client(conn, channel, rxrpc_client_chan_disconnect); if (WARN_ON(chan->call != call)) return; may_reuse = rxrpc_may_reuse_conn(conn); /* If a client call was exposed to the world, we save the result for * retransmission. * * We use a barrier here so that the call number and abort code can be * read without needing to take a lock. * * TODO: Make the incoming packet handler check this and handle * terminal retransmission without requiring access to the call. */ if (test_bit(RXRPC_CALL_EXPOSED, &call->flags)) { _debug("exposed %u,%u", call->call_id, call->abort_code); __rxrpc_disconnect_call(conn, call); if (test_and_clear_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags)) { trace_rxrpc_client(conn, channel, rxrpc_client_to_active); bundle->try_upgrade = false; if (may_reuse) rxrpc_activate_channels(bundle); } } /* See if we can pass the channel directly to another call. */ if (may_reuse && !list_empty(&bundle->waiting_calls)) { trace_rxrpc_client(conn, channel, rxrpc_client_chan_pass); rxrpc_activate_one_channel(conn, channel); return; } /* Schedule the final ACK to be transmitted in a short while so that it * can be skipped if we find a follow-on call. The first DATA packet * of the follow on call will implicitly ACK this call. */ if (call->completion == RXRPC_CALL_SUCCEEDED && test_bit(RXRPC_CALL_EXPOSED, &call->flags)) { unsigned long final_ack_at = jiffies + 2; WRITE_ONCE(chan->final_ack_at, final_ack_at); smp_wmb(); /* vs rxrpc_process_delayed_final_acks() */ set_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags); rxrpc_reduce_conn_timer(conn, final_ack_at); } /* Deactivate the channel. */ chan->call = NULL; set_bit(conn->bundle_shift + channel, &conn->bundle->avail_chans); conn->act_chans &= ~(1 << channel); /* If no channels remain active, then put the connection on the idle * list for a short while. Give it a ref to stop it going away if it * becomes unbundled. */ if (!conn->act_chans) { trace_rxrpc_client(conn, channel, rxrpc_client_to_idle); conn->idle_timestamp = jiffies; rxrpc_get_connection(conn, rxrpc_conn_get_idle); list_move_tail(&conn->cache_link, &local->idle_client_conns); rxrpc_set_client_reap_timer(local); } } /* * Remove a connection from a bundle. */ static void rxrpc_unbundle_conn(struct rxrpc_connection *conn) { struct rxrpc_bundle *bundle = conn->bundle; unsigned int bindex; int i; _enter("C=%x", conn->debug_id); if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK) rxrpc_process_delayed_final_acks(conn, true); bindex = conn->bundle_shift / RXRPC_MAXCALLS; if (bundle->conns[bindex] == conn) { _debug("clear slot %u", bindex); bundle->conns[bindex] = NULL; for (i = 0; i < RXRPC_MAXCALLS; i++) clear_bit(conn->bundle_shift + i, &bundle->avail_chans); rxrpc_put_client_connection_id(bundle->local, conn); rxrpc_deactivate_bundle(bundle); rxrpc_put_connection(conn, rxrpc_conn_put_unbundle); } } /* * Drop the active count on a bundle. */ void rxrpc_deactivate_bundle(struct rxrpc_bundle *bundle) { struct rxrpc_local *local; bool need_put = false; if (!bundle) return; local = bundle->local; if (atomic_dec_and_lock(&bundle->active, &local->client_bundles_lock)) { if (!bundle->exclusive) { _debug("erase bundle"); rb_erase(&bundle->local_node, &local->client_bundles); need_put = true; } spin_unlock(&local->client_bundles_lock); if (need_put) rxrpc_put_bundle(bundle, rxrpc_bundle_put_discard); } } /* * Clean up a dead client connection. */ void rxrpc_kill_client_conn(struct rxrpc_connection *conn) { struct rxrpc_local *local = conn->local; struct rxrpc_net *rxnet = local->rxnet; _enter("C=%x", conn->debug_id); trace_rxrpc_client(conn, -1, rxrpc_client_cleanup); atomic_dec(&rxnet->nr_client_conns); rxrpc_put_client_connection_id(local, conn); } /* * Discard expired client connections from the idle list. Each conn in the * idle list has been exposed and holds an extra ref because of that. * * This may be called from conn setup or from a work item so cannot be * considered non-reentrant. */ void rxrpc_discard_expired_client_conns(struct rxrpc_local *local) { struct rxrpc_connection *conn; unsigned long expiry, conn_expires_at, now; unsigned int nr_conns; _enter(""); /* We keep an estimate of what the number of conns ought to be after * we've discarded some so that we don't overdo the discarding. */ nr_conns = atomic_read(&local->rxnet->nr_client_conns); next: conn = list_first_entry_or_null(&local->idle_client_conns, struct rxrpc_connection, cache_link); if (!conn) return; if (!local->kill_all_client_conns) { /* If the number of connections is over the reap limit, we * expedite discard by reducing the expiry timeout. We must, * however, have at least a short grace period to be able to do * final-ACK or ABORT retransmission. */ expiry = rxrpc_conn_idle_client_expiry; if (nr_conns > rxrpc_reap_client_connections) expiry = rxrpc_conn_idle_client_fast_expiry; if (conn->local->service_closed) expiry = rxrpc_closed_conn_expiry * HZ; conn_expires_at = conn->idle_timestamp + expiry; now = READ_ONCE(jiffies); if (time_after(conn_expires_at, now)) goto not_yet_expired; } atomic_dec(&conn->active); trace_rxrpc_client(conn, -1, rxrpc_client_discard); list_del_init(&conn->cache_link); rxrpc_unbundle_conn(conn); /* Drop the ->cache_link ref */ rxrpc_put_connection(conn, rxrpc_conn_put_discard_idle); nr_conns--; goto next; not_yet_expired: /* The connection at the front of the queue hasn't yet expired, so * schedule the work item for that point if we discarded something. * * We don't worry if the work item is already scheduled - it can look * after rescheduling itself at a later time. We could cancel it, but * then things get messier. */ _debug("not yet"); if (!local->kill_all_client_conns) timer_reduce(&local->client_conn_reap_timer, conn_expires_at); _leave(""); } /* * Clean up the client connections on a local endpoint. */ void rxrpc_clean_up_local_conns(struct rxrpc_local *local) { struct rxrpc_connection *conn; _enter(""); local->kill_all_client_conns = true; del_timer_sync(&local->client_conn_reap_timer); while ((conn = list_first_entry_or_null(&local->idle_client_conns, struct rxrpc_connection, cache_link))) { list_del_init(&conn->cache_link); atomic_dec(&conn->active); trace_rxrpc_client(conn, -1, rxrpc_client_discard); rxrpc_unbundle_conn(conn); rxrpc_put_connection(conn, rxrpc_conn_put_local_dead); } _leave(" [culled]"); }
linux-master
net/rxrpc/conn_client.c
// SPDX-License-Identifier: GPL-2.0-or-later /* RxRPC key management * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) * * RxRPC keys should have a description of describing their purpose: * "[email protected]" */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <crypto/skcipher.h> #include <linux/module.h> #include <linux/net.h> #include <linux/skbuff.h> #include <linux/key-type.h> #include <linux/ctype.h> #include <linux/slab.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include <keys/rxrpc-type.h> #include <keys/user-type.h> #include "ar-internal.h" static int rxrpc_preparse(struct key_preparsed_payload *); static void rxrpc_free_preparse(struct key_preparsed_payload *); static void rxrpc_destroy(struct key *); static void rxrpc_describe(const struct key *, struct seq_file *); static long rxrpc_read(const struct key *, char *, size_t); /* * rxrpc defined keys take an arbitrary string as the description and an * arbitrary blob of data as the payload */ struct key_type key_type_rxrpc = { .name = "rxrpc", .flags = KEY_TYPE_NET_DOMAIN, .preparse = rxrpc_preparse, .free_preparse = rxrpc_free_preparse, .instantiate = generic_key_instantiate, .destroy = rxrpc_destroy, .describe = rxrpc_describe, .read = rxrpc_read, }; EXPORT_SYMBOL(key_type_rxrpc); /* * parse an RxKAD type XDR format token * - the caller guarantees we have at least 4 words */ static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep, size_t datalen, const __be32 *xdr, unsigned int toklen) { struct rxrpc_key_token *token, **pptoken; time64_t expiry; size_t plen; u32 tktlen; _enter(",{%x,%x,%x,%x},%u", ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]), toklen); if (toklen <= 8 * 4) return -EKEYREJECTED; tktlen = ntohl(xdr[7]); _debug("tktlen: %x", tktlen); if (tktlen > AFSTOKEN_RK_TIX_MAX) return -EKEYREJECTED; if (toklen < 8 * 4 + tktlen) return -EKEYREJECTED; plen = sizeof(*token) + sizeof(*token->kad) + tktlen; prep->quotalen = datalen + plen; plen -= sizeof(*token); token = kzalloc(sizeof(*token), GFP_KERNEL); if (!token) return -ENOMEM; token->kad = kzalloc(plen, GFP_KERNEL); if (!token->kad) { kfree(token); return -ENOMEM; } token->security_index = RXRPC_SECURITY_RXKAD; token->kad->ticket_len = tktlen; token->kad->vice_id = ntohl(xdr[0]); token->kad->kvno = ntohl(xdr[1]); token->kad->start = ntohl(xdr[4]); token->kad->expiry = ntohl(xdr[5]); token->kad->primary_flag = ntohl(xdr[6]); memcpy(&token->kad->session_key, &xdr[2], 8); memcpy(&token->kad->ticket, &xdr[8], tktlen); _debug("SCIX: %u", token->security_index); _debug("TLEN: %u", token->kad->ticket_len); _debug("EXPY: %x", token->kad->expiry); _debug("KVNO: %u", token->kad->kvno); _debug("PRIM: %u", token->kad->primary_flag); _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x", token->kad->session_key[0], token->kad->session_key[1], token->kad->session_key[2], token->kad->session_key[3], token->kad->session_key[4], token->kad->session_key[5], token->kad->session_key[6], token->kad->session_key[7]); if (token->kad->ticket_len >= 8) _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x", token->kad->ticket[0], token->kad->ticket[1], token->kad->ticket[2], token->kad->ticket[3], token->kad->ticket[4], token->kad->ticket[5], token->kad->ticket[6], token->kad->ticket[7]); /* count the number of tokens attached */ prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1); /* attach the data */ for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0]; *pptoken; pptoken = &(*pptoken)->next) continue; *pptoken = token; expiry = rxrpc_u32_to_time64(token->kad->expiry); if (expiry < prep->expiry) prep->expiry = expiry; _leave(" = 0"); return 0; } /* * attempt to parse the data as the XDR format * - the caller guarantees we have more than 7 words */ static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep) { const __be32 *xdr = prep->data, *token, *p; const char *cp; unsigned int len, paddedlen, loop, ntoken, toklen, sec_ix; size_t datalen = prep->datalen; int ret, ret2; _enter(",{%x,%x,%x,%x},%zu", ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]), prep->datalen); if (datalen > AFSTOKEN_LENGTH_MAX) goto not_xdr; /* XDR is an array of __be32's */ if (datalen & 3) goto not_xdr; /* the flags should be 0 (the setpag bit must be handled by * userspace) */ if (ntohl(*xdr++) != 0) goto not_xdr; datalen -= 4; /* check the cell name */ len = ntohl(*xdr++); if (len < 1 || len > AFSTOKEN_CELL_MAX) goto not_xdr; datalen -= 4; paddedlen = (len + 3) & ~3; if (paddedlen > datalen) goto not_xdr; cp = (const char *) xdr; for (loop = 0; loop < len; loop++) if (!isprint(cp[loop])) goto not_xdr; for (; loop < paddedlen; loop++) if (cp[loop]) goto not_xdr; _debug("cellname: [%u/%u] '%*.*s'", len, paddedlen, len, len, (const char *) xdr); datalen -= paddedlen; xdr += paddedlen >> 2; /* get the token count */ if (datalen < 12) goto not_xdr; ntoken = ntohl(*xdr++); datalen -= 4; _debug("ntoken: %x", ntoken); if (ntoken < 1 || ntoken > AFSTOKEN_MAX) goto not_xdr; /* check each token wrapper */ p = xdr; loop = ntoken; do { if (datalen < 8) goto not_xdr; toklen = ntohl(*p++); sec_ix = ntohl(*p); datalen -= 4; _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix); paddedlen = (toklen + 3) & ~3; if (toklen < 20 || toklen > datalen || paddedlen > datalen) goto not_xdr; datalen -= paddedlen; p += paddedlen >> 2; } while (--loop > 0); _debug("remainder: %zu", datalen); if (datalen != 0) goto not_xdr; /* okay: we're going to assume it's valid XDR format * - we ignore the cellname, relying on the key to be correctly named */ ret = -EPROTONOSUPPORT; do { toklen = ntohl(*xdr++); token = xdr; xdr += (toklen + 3) / 4; sec_ix = ntohl(*token++); toklen -= 4; _debug("TOKEN type=%x len=%x", sec_ix, toklen); switch (sec_ix) { case RXRPC_SECURITY_RXKAD: ret2 = rxrpc_preparse_xdr_rxkad(prep, datalen, token, toklen); break; default: ret2 = -EPROTONOSUPPORT; break; } switch (ret2) { case 0: ret = 0; break; case -EPROTONOSUPPORT: break; case -ENOPKG: if (ret != 0) ret = -ENOPKG; break; default: ret = ret2; goto error; } } while (--ntoken > 0); error: _leave(" = %d", ret); return ret; not_xdr: _leave(" = -EPROTO"); return -EPROTO; } /* * Preparse an rxrpc defined key. * * Data should be of the form: * OFFSET LEN CONTENT * 0 4 key interface version number * 4 2 security index (type) * 6 2 ticket length * 8 4 key expiry time (time_t) * 12 4 kvno * 16 8 session key * 24 [len] ticket * * if no data is provided, then a no-security key is made */ static int rxrpc_preparse(struct key_preparsed_payload *prep) { const struct rxrpc_key_data_v1 *v1; struct rxrpc_key_token *token, **pp; time64_t expiry; size_t plen; u32 kver; int ret; _enter("%zu", prep->datalen); /* handle a no-security key */ if (!prep->data && prep->datalen == 0) return 0; /* determine if the XDR payload format is being used */ if (prep->datalen > 7 * 4) { ret = rxrpc_preparse_xdr(prep); if (ret != -EPROTO) return ret; } /* get the key interface version number */ ret = -EINVAL; if (prep->datalen <= 4 || !prep->data) goto error; memcpy(&kver, prep->data, sizeof(kver)); prep->data += sizeof(kver); prep->datalen -= sizeof(kver); _debug("KEY I/F VERSION: %u", kver); ret = -EKEYREJECTED; if (kver != 1) goto error; /* deal with a version 1 key */ ret = -EINVAL; if (prep->datalen < sizeof(*v1)) goto error; v1 = prep->data; if (prep->datalen != sizeof(*v1) + v1->ticket_length) goto error; _debug("SCIX: %u", v1->security_index); _debug("TLEN: %u", v1->ticket_length); _debug("EXPY: %x", v1->expiry); _debug("KVNO: %u", v1->kvno); _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x", v1->session_key[0], v1->session_key[1], v1->session_key[2], v1->session_key[3], v1->session_key[4], v1->session_key[5], v1->session_key[6], v1->session_key[7]); if (v1->ticket_length >= 8) _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x", v1->ticket[0], v1->ticket[1], v1->ticket[2], v1->ticket[3], v1->ticket[4], v1->ticket[5], v1->ticket[6], v1->ticket[7]); ret = -EPROTONOSUPPORT; if (v1->security_index != RXRPC_SECURITY_RXKAD) goto error; plen = sizeof(*token->kad) + v1->ticket_length; prep->quotalen = plen + sizeof(*token); ret = -ENOMEM; token = kzalloc(sizeof(*token), GFP_KERNEL); if (!token) goto error; token->kad = kzalloc(plen, GFP_KERNEL); if (!token->kad) goto error_free; token->security_index = RXRPC_SECURITY_RXKAD; token->kad->ticket_len = v1->ticket_length; token->kad->expiry = v1->expiry; token->kad->kvno = v1->kvno; memcpy(&token->kad->session_key, &v1->session_key, 8); memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length); /* count the number of tokens attached */ prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1); /* attach the data */ pp = (struct rxrpc_key_token **)&prep->payload.data[0]; while (*pp) pp = &(*pp)->next; *pp = token; expiry = rxrpc_u32_to_time64(token->kad->expiry); if (expiry < prep->expiry) prep->expiry = expiry; token = NULL; ret = 0; error_free: kfree(token); error: return ret; } /* * Free token list. */ static void rxrpc_free_token_list(struct rxrpc_key_token *token) { struct rxrpc_key_token *next; for (; token; token = next) { next = token->next; switch (token->security_index) { case RXRPC_SECURITY_RXKAD: kfree(token->kad); break; default: pr_err("Unknown token type %x on rxrpc key\n", token->security_index); BUG(); } kfree(token); } } /* * Clean up preparse data. */ static void rxrpc_free_preparse(struct key_preparsed_payload *prep) { rxrpc_free_token_list(prep->payload.data[0]); } /* * dispose of the data dangling from the corpse of a rxrpc key */ static void rxrpc_destroy(struct key *key) { rxrpc_free_token_list(key->payload.data[0]); } /* * describe the rxrpc key */ static void rxrpc_describe(const struct key *key, struct seq_file *m) { const struct rxrpc_key_token *token; const char *sep = ": "; seq_puts(m, key->description); for (token = key->payload.data[0]; token; token = token->next) { seq_puts(m, sep); switch (token->security_index) { case RXRPC_SECURITY_RXKAD: seq_puts(m, "ka"); break; default: /* we have a ticket we can't encode */ seq_printf(m, "%u", token->security_index); break; } sep = " "; } } /* * grab the security key for a socket */ int rxrpc_request_key(struct rxrpc_sock *rx, sockptr_t optval, int optlen) { struct key *key; char *description; _enter(""); if (optlen <= 0 || optlen > PAGE_SIZE - 1 || rx->securities) return -EINVAL; description = memdup_sockptr_nul(optval, optlen); if (IS_ERR(description)) return PTR_ERR(description); key = request_key_net(&key_type_rxrpc, description, sock_net(&rx->sk), NULL); if (IS_ERR(key)) { kfree(description); _leave(" = %ld", PTR_ERR(key)); return PTR_ERR(key); } rx->key = key; kfree(description); _leave(" = 0 [key %x]", key->serial); return 0; } /* * generate a server data key */ int rxrpc_get_server_data_key(struct rxrpc_connection *conn, const void *session_key, time64_t expiry, u32 kvno) { const struct cred *cred = current_cred(); struct key *key; int ret; struct { u32 kver; struct rxrpc_key_data_v1 v1; } data; _enter(""); key = key_alloc(&key_type_rxrpc, "x", GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0, KEY_ALLOC_NOT_IN_QUOTA, NULL); if (IS_ERR(key)) { _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key)); return -ENOMEM; } _debug("key %d", key_serial(key)); data.kver = 1; data.v1.security_index = RXRPC_SECURITY_RXKAD; data.v1.ticket_length = 0; data.v1.expiry = rxrpc_time64_to_u32(expiry); data.v1.kvno = 0; memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key)); ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL); if (ret < 0) goto error; conn->key = key; _leave(" = 0 [%d]", key_serial(key)); return 0; error: key_revoke(key); key_put(key); _leave(" = -ENOMEM [ins %d]", ret); return -ENOMEM; } EXPORT_SYMBOL(rxrpc_get_server_data_key); /** * rxrpc_get_null_key - Generate a null RxRPC key * @keyname: The name to give the key. * * Generate a null RxRPC key that can be used to indicate anonymous security is * required for a particular domain. */ struct key *rxrpc_get_null_key(const char *keyname) { const struct cred *cred = current_cred(); struct key *key; int ret; key = key_alloc(&key_type_rxrpc, keyname, GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL); if (IS_ERR(key)) return key; ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL); if (ret < 0) { key_revoke(key); key_put(key); return ERR_PTR(ret); } return key; } EXPORT_SYMBOL(rxrpc_get_null_key); /* * read the contents of an rxrpc key * - this returns the result in XDR form */ static long rxrpc_read(const struct key *key, char *buffer, size_t buflen) { const struct rxrpc_key_token *token; size_t size; __be32 *xdr, *oldxdr; u32 cnlen, toksize, ntoks, tok, zero; u16 toksizes[AFSTOKEN_MAX]; _enter(""); /* we don't know what form we should return non-AFS keys in */ if (memcmp(key->description, "afs@", 4) != 0) return -EOPNOTSUPP; cnlen = strlen(key->description + 4); #define RND(X) (((X) + 3) & ~3) /* AFS keys we return in XDR form, so we need to work out the size of * the XDR */ size = 2 * 4; /* flags, cellname len */ size += RND(cnlen); /* cellname */ size += 1 * 4; /* token count */ ntoks = 0; for (token = key->payload.data[0]; token; token = token->next) { toksize = 4; /* sec index */ switch (token->security_index) { case RXRPC_SECURITY_RXKAD: toksize += 8 * 4; /* viceid, kvno, key*2, begin, * end, primary, tktlen */ if (!token->no_leak_key) toksize += RND(token->kad->ticket_len); break; default: /* we have a ticket we can't encode */ pr_err("Unsupported key token type (%u)\n", token->security_index); return -ENOPKG; } _debug("token[%u]: toksize=%u", ntoks, toksize); if (WARN_ON(toksize > AFSTOKEN_LENGTH_MAX)) return -EIO; toksizes[ntoks++] = toksize; size += toksize + 4; /* each token has a length word */ } #undef RND if (!buffer || buflen < size) return size; xdr = (__be32 *)buffer; zero = 0; #define ENCODE(x) \ do { \ *xdr++ = htonl(x); \ } while(0) #define ENCODE_DATA(l, s) \ do { \ u32 _l = (l); \ ENCODE(l); \ memcpy(xdr, (s), _l); \ if (_l & 3) \ memcpy((u8 *)xdr + _l, &zero, 4 - (_l & 3)); \ xdr += (_l + 3) >> 2; \ } while(0) #define ENCODE_BYTES(l, s) \ do { \ u32 _l = (l); \ memcpy(xdr, (s), _l); \ if (_l & 3) \ memcpy((u8 *)xdr + _l, &zero, 4 - (_l & 3)); \ xdr += (_l + 3) >> 2; \ } while(0) #define ENCODE64(x) \ do { \ __be64 y = cpu_to_be64(x); \ memcpy(xdr, &y, 8); \ xdr += 8 >> 2; \ } while(0) #define ENCODE_STR(s) \ do { \ const char *_s = (s); \ ENCODE_DATA(strlen(_s), _s); \ } while(0) ENCODE(0); /* flags */ ENCODE_DATA(cnlen, key->description + 4); /* cellname */ ENCODE(ntoks); tok = 0; for (token = key->payload.data[0]; token; token = token->next) { toksize = toksizes[tok++]; ENCODE(toksize); oldxdr = xdr; ENCODE(token->security_index); switch (token->security_index) { case RXRPC_SECURITY_RXKAD: ENCODE(token->kad->vice_id); ENCODE(token->kad->kvno); ENCODE_BYTES(8, token->kad->session_key); ENCODE(token->kad->start); ENCODE(token->kad->expiry); ENCODE(token->kad->primary_flag); if (token->no_leak_key) ENCODE(0); else ENCODE_DATA(token->kad->ticket_len, token->kad->ticket); break; default: pr_err("Unsupported key token type (%u)\n", token->security_index); return -ENOPKG; } if (WARN_ON((unsigned long)xdr - (unsigned long)oldxdr != toksize)) return -EIO; } #undef ENCODE_STR #undef ENCODE_DATA #undef ENCODE64 #undef ENCODE if (WARN_ON(tok != ntoks)) return -EIO; if (WARN_ON((unsigned long)xdr - (unsigned long)buffer != size)) return -EIO; _leave(" = %zu", size); return size; }
linux-master
net/rxrpc/key.c
// SPDX-License-Identifier: GPL-2.0-or-later /* Miscellaneous bits * * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #include <linux/kernel.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include "ar-internal.h" /* * The maximum listening backlog queue size that may be set on a socket by * listen(). */ unsigned int rxrpc_max_backlog __read_mostly = 10; /* * How long to wait before scheduling an ACK with subtype DELAY (in jiffies). * * We use this when we've received new data packets. If those packets aren't * all consumed within this time we will send a DELAY ACK if an ACK was not * requested to let the sender know it doesn't need to resend. */ unsigned long rxrpc_soft_ack_delay = HZ; /* * How long to wait before scheduling an ACK with subtype IDLE (in jiffies). * * We use this when we've consumed some previously soft-ACK'd packets when * further packets aren't immediately received to decide when to send an IDLE * ACK let the other end know that it can free up its Tx buffer space. */ unsigned long rxrpc_idle_ack_delay = HZ / 2; /* * Receive window size in packets. This indicates the maximum number of * unconsumed received packets we're willing to retain in memory. Once this * limit is hit, we should generate an EXCEEDS_WINDOW ACK and discard further * packets. */ unsigned int rxrpc_rx_window_size = 255; /* * Maximum Rx MTU size. This indicates to the sender the size of jumbo packet * made by gluing normal packets together that we're willing to handle. */ unsigned int rxrpc_rx_mtu = 5692; /* * The maximum number of fragments in a received jumbo packet that we tell the * sender that we're willing to handle. */ unsigned int rxrpc_rx_jumbo_max = 4; #ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY /* * The delay to inject into packet reception. */ unsigned long rxrpc_inject_rx_delay; #endif
linux-master
net/rxrpc/misc.c
// SPDX-License-Identifier: GPL-2.0-or-later /* RxRPC security handling * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #include <linux/module.h> #include <linux/net.h> #include <linux/skbuff.h> #include <linux/udp.h> #include <linux/crypto.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include <keys/rxrpc-type.h> #include "ar-internal.h" static const struct rxrpc_security *rxrpc_security_types[] = { [RXRPC_SECURITY_NONE] = &rxrpc_no_security, #ifdef CONFIG_RXKAD [RXRPC_SECURITY_RXKAD] = &rxkad, #endif }; int __init rxrpc_init_security(void) { int i, ret; for (i = 0; i < ARRAY_SIZE(rxrpc_security_types); i++) { if (rxrpc_security_types[i]) { ret = rxrpc_security_types[i]->init(); if (ret < 0) goto failed; } } return 0; failed: for (i--; i >= 0; i--) if (rxrpc_security_types[i]) rxrpc_security_types[i]->exit(); return ret; } void rxrpc_exit_security(void) { int i; for (i = 0; i < ARRAY_SIZE(rxrpc_security_types); i++) if (rxrpc_security_types[i]) rxrpc_security_types[i]->exit(); } /* * look up an rxrpc security module */ const struct rxrpc_security *rxrpc_security_lookup(u8 security_index) { if (security_index >= ARRAY_SIZE(rxrpc_security_types)) return NULL; return rxrpc_security_types[security_index]; } /* * Initialise the security on a client call. */ int rxrpc_init_client_call_security(struct rxrpc_call *call) { const struct rxrpc_security *sec = &rxrpc_no_security; struct rxrpc_key_token *token; struct key *key = call->key; int ret; if (!key) goto found; ret = key_validate(key); if (ret < 0) return ret; for (token = key->payload.data[0]; token; token = token->next) { sec = rxrpc_security_lookup(token->security_index); if (sec) goto found; } return -EKEYREJECTED; found: call->security = sec; call->security_ix = sec->security_index; return 0; } /* * initialise the security on a client connection */ int rxrpc_init_client_conn_security(struct rxrpc_connection *conn) { struct rxrpc_key_token *token; struct key *key = conn->key; int ret = 0; _enter("{%d},{%x}", conn->debug_id, key_serial(key)); for (token = key->payload.data[0]; token; token = token->next) { if (token->security_index == conn->security->security_index) goto found; } return -EKEYREJECTED; found: mutex_lock(&conn->security_lock); if (conn->state == RXRPC_CONN_CLIENT_UNSECURED) { ret = conn->security->init_connection_security(conn, token); if (ret == 0) { spin_lock(&conn->state_lock); if (conn->state == RXRPC_CONN_CLIENT_UNSECURED) conn->state = RXRPC_CONN_CLIENT; spin_unlock(&conn->state_lock); } } mutex_unlock(&conn->security_lock); return ret; } /* * Set the ops a server connection. */ const struct rxrpc_security *rxrpc_get_incoming_security(struct rxrpc_sock *rx, struct sk_buff *skb) { const struct rxrpc_security *sec; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); _enter(""); sec = rxrpc_security_lookup(sp->hdr.securityIndex); if (!sec) { rxrpc_direct_abort(skb, rxrpc_abort_unsupported_security, RX_INVALID_OPERATION, -EKEYREJECTED); return NULL; } if (sp->hdr.securityIndex != RXRPC_SECURITY_NONE && !rx->securities) { rxrpc_direct_abort(skb, rxrpc_abort_no_service_key, sec->no_key_abort, -EKEYREJECTED); return NULL; } return sec; } /* * Find the security key for a server connection. */ struct key *rxrpc_look_up_server_security(struct rxrpc_connection *conn, struct sk_buff *skb, u32 kvno, u32 enctype) { struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct rxrpc_sock *rx; struct key *key = ERR_PTR(-EKEYREJECTED); key_ref_t kref = NULL; char kdesc[5 + 1 + 3 + 1 + 12 + 1 + 12 + 1]; int ret; _enter(""); if (enctype) sprintf(kdesc, "%u:%u:%u:%u", sp->hdr.serviceId, sp->hdr.securityIndex, kvno, enctype); else if (kvno) sprintf(kdesc, "%u:%u:%u", sp->hdr.serviceId, sp->hdr.securityIndex, kvno); else sprintf(kdesc, "%u:%u", sp->hdr.serviceId, sp->hdr.securityIndex); read_lock(&conn->local->services_lock); rx = conn->local->service; if (!rx) goto out; /* look through the service's keyring */ kref = keyring_search(make_key_ref(rx->securities, 1UL), &key_type_rxrpc_s, kdesc, true); if (IS_ERR(kref)) { key = ERR_CAST(kref); goto out; } key = key_ref_to_ptr(kref); ret = key_validate(key); if (ret < 0) { key_put(key); key = ERR_PTR(ret); goto out; } out: read_unlock(&conn->local->services_lock); return key; }
linux-master
net/rxrpc/security.c
// SPDX-License-Identifier: GPL-2.0-or-later /* In-kernel rxperf server for testing purposes. * * Copyright (C) 2022 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #define pr_fmt(fmt) "rxperf: " fmt #include <linux/module.h> #include <linux/slab.h> #include <net/sock.h> #include <net/af_rxrpc.h> #define RXRPC_TRACE_ONLY_DEFINE_ENUMS #include <trace/events/rxrpc.h> MODULE_DESCRIPTION("rxperf test server (afs)"); MODULE_AUTHOR("Red Hat, Inc."); MODULE_LICENSE("GPL"); #define RXPERF_PORT 7009 #define RX_PERF_SERVICE 147 #define RX_PERF_VERSION 3 #define RX_PERF_SEND 0 #define RX_PERF_RECV 1 #define RX_PERF_RPC 3 #define RX_PERF_FILE 4 #define RX_PERF_MAGIC_COOKIE 0x4711 struct rxperf_proto_params { __be32 version; __be32 type; __be32 rsize; __be32 wsize; } __packed; static const u8 rxperf_magic_cookie[] = { 0x00, 0x00, 0x47, 0x11 }; static const u8 secret[8] = { 0xa7, 0x83, 0x8a, 0xcb, 0xc7, 0x83, 0xec, 0x94 }; enum rxperf_call_state { RXPERF_CALL_SV_AWAIT_PARAMS, /* Server: Awaiting parameter block */ RXPERF_CALL_SV_AWAIT_REQUEST, /* Server: Awaiting request data */ RXPERF_CALL_SV_REPLYING, /* Server: Replying */ RXPERF_CALL_SV_AWAIT_ACK, /* Server: Awaiting final ACK */ RXPERF_CALL_COMPLETE, /* Completed or failed */ }; struct rxperf_call { struct rxrpc_call *rxcall; struct iov_iter iter; struct kvec kvec[1]; struct work_struct work; const char *type; size_t iov_len; size_t req_len; /* Size of request blob */ size_t reply_len; /* Size of reply blob */ unsigned int debug_id; unsigned int operation_id; struct rxperf_proto_params params; __be32 tmp[2]; s32 abort_code; enum rxperf_call_state state; short error; unsigned short unmarshal; u16 service_id; int (*deliver)(struct rxperf_call *call); void (*processor)(struct work_struct *work); }; static struct socket *rxperf_socket; static struct key *rxperf_sec_keyring; /* Ring of security/crypto keys */ static struct workqueue_struct *rxperf_workqueue; static void rxperf_deliver_to_call(struct work_struct *work); static int rxperf_deliver_param_block(struct rxperf_call *call); static int rxperf_deliver_request(struct rxperf_call *call); static int rxperf_process_call(struct rxperf_call *call); static void rxperf_charge_preallocation(struct work_struct *work); static DECLARE_WORK(rxperf_charge_preallocation_work, rxperf_charge_preallocation); static inline void rxperf_set_call_state(struct rxperf_call *call, enum rxperf_call_state to) { call->state = to; } static inline void rxperf_set_call_complete(struct rxperf_call *call, int error, s32 remote_abort) { if (call->state != RXPERF_CALL_COMPLETE) { call->abort_code = remote_abort; call->error = error; call->state = RXPERF_CALL_COMPLETE; } } static void rxperf_rx_discard_new_call(struct rxrpc_call *rxcall, unsigned long user_call_ID) { kfree((struct rxperf_call *)user_call_ID); } static void rxperf_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall, unsigned long user_call_ID) { queue_work(rxperf_workqueue, &rxperf_charge_preallocation_work); } static void rxperf_queue_call_work(struct rxperf_call *call) { queue_work(rxperf_workqueue, &call->work); } static void rxperf_notify_rx(struct sock *sk, struct rxrpc_call *rxcall, unsigned long call_user_ID) { struct rxperf_call *call = (struct rxperf_call *)call_user_ID; if (call->state != RXPERF_CALL_COMPLETE) rxperf_queue_call_work(call); } static void rxperf_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID) { struct rxperf_call *call = (struct rxperf_call *)user_call_ID; call->rxcall = rxcall; } static void rxperf_notify_end_reply_tx(struct sock *sock, struct rxrpc_call *rxcall, unsigned long call_user_ID) { rxperf_set_call_state((struct rxperf_call *)call_user_ID, RXPERF_CALL_SV_AWAIT_ACK); } /* * Charge the incoming call preallocation. */ static void rxperf_charge_preallocation(struct work_struct *work) { struct rxperf_call *call; for (;;) { call = kzalloc(sizeof(*call), GFP_KERNEL); if (!call) break; call->type = "unset"; call->debug_id = atomic_inc_return(&rxrpc_debug_id); call->deliver = rxperf_deliver_param_block; call->state = RXPERF_CALL_SV_AWAIT_PARAMS; call->service_id = RX_PERF_SERVICE; call->iov_len = sizeof(call->params); call->kvec[0].iov_len = sizeof(call->params); call->kvec[0].iov_base = &call->params; iov_iter_kvec(&call->iter, READ, call->kvec, 1, call->iov_len); INIT_WORK(&call->work, rxperf_deliver_to_call); if (rxrpc_kernel_charge_accept(rxperf_socket, rxperf_notify_rx, rxperf_rx_attach, (unsigned long)call, GFP_KERNEL, call->debug_id) < 0) break; call = NULL; } kfree(call); } /* * Open an rxrpc socket and bind it to be a server for callback notifications * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT */ static int rxperf_open_socket(void) { struct sockaddr_rxrpc srx; struct socket *socket; int ret; ret = sock_create_kern(&init_net, AF_RXRPC, SOCK_DGRAM, PF_INET6, &socket); if (ret < 0) goto error_1; socket->sk->sk_allocation = GFP_NOFS; /* bind the callback manager's address to make this a server socket */ memset(&srx, 0, sizeof(srx)); srx.srx_family = AF_RXRPC; srx.srx_service = RX_PERF_SERVICE; srx.transport_type = SOCK_DGRAM; srx.transport_len = sizeof(srx.transport.sin6); srx.transport.sin6.sin6_family = AF_INET6; srx.transport.sin6.sin6_port = htons(RXPERF_PORT); ret = rxrpc_sock_set_min_security_level(socket->sk, RXRPC_SECURITY_ENCRYPT); if (ret < 0) goto error_2; ret = rxrpc_sock_set_security_keyring(socket->sk, rxperf_sec_keyring); ret = kernel_bind(socket, (struct sockaddr *)&srx, sizeof(srx)); if (ret < 0) goto error_2; rxrpc_kernel_new_call_notification(socket, rxperf_rx_new_call, rxperf_rx_discard_new_call); ret = kernel_listen(socket, INT_MAX); if (ret < 0) goto error_2; rxperf_socket = socket; rxperf_charge_preallocation(&rxperf_charge_preallocation_work); return 0; error_2: sock_release(socket); error_1: pr_err("Can't set up rxperf socket: %d\n", ret); return ret; } /* * close the rxrpc socket rxperf was using */ static void rxperf_close_socket(void) { kernel_listen(rxperf_socket, 0); kernel_sock_shutdown(rxperf_socket, SHUT_RDWR); flush_workqueue(rxperf_workqueue); sock_release(rxperf_socket); } /* * Log remote abort codes that indicate that we have a protocol disagreement * with the server. */ static void rxperf_log_error(struct rxperf_call *call, s32 remote_abort) { static int max = 0; const char *msg; int m; switch (remote_abort) { case RX_EOF: msg = "unexpected EOF"; break; case RXGEN_CC_MARSHAL: msg = "client marshalling"; break; case RXGEN_CC_UNMARSHAL: msg = "client unmarshalling"; break; case RXGEN_SS_MARSHAL: msg = "server marshalling"; break; case RXGEN_SS_UNMARSHAL: msg = "server unmarshalling"; break; case RXGEN_DECODE: msg = "opcode decode"; break; case RXGEN_SS_XDRFREE: msg = "server XDR cleanup"; break; case RXGEN_CC_XDRFREE: msg = "client XDR cleanup"; break; case -32: msg = "insufficient data"; break; default: return; } m = max; if (m < 3) { max = m + 1; pr_info("Peer reported %s failure on %s\n", msg, call->type); } } /* * deliver messages to a call */ static void rxperf_deliver_to_call(struct work_struct *work) { struct rxperf_call *call = container_of(work, struct rxperf_call, work); enum rxperf_call_state state; u32 abort_code, remote_abort = 0; int ret = 0; if (call->state == RXPERF_CALL_COMPLETE) return; while (state = call->state, state == RXPERF_CALL_SV_AWAIT_PARAMS || state == RXPERF_CALL_SV_AWAIT_REQUEST || state == RXPERF_CALL_SV_AWAIT_ACK ) { if (state == RXPERF_CALL_SV_AWAIT_ACK) { if (!rxrpc_kernel_check_life(rxperf_socket, call->rxcall)) goto call_complete; return; } ret = call->deliver(call); if (ret == 0) ret = rxperf_process_call(call); switch (ret) { case 0: continue; case -EINPROGRESS: case -EAGAIN: return; case -ECONNABORTED: rxperf_log_error(call, call->abort_code); goto call_complete; case -EOPNOTSUPP: abort_code = RXGEN_OPCODE; rxrpc_kernel_abort_call(rxperf_socket, call->rxcall, abort_code, ret, rxperf_abort_op_not_supported); goto call_complete; case -ENOTSUPP: abort_code = RX_USER_ABORT; rxrpc_kernel_abort_call(rxperf_socket, call->rxcall, abort_code, ret, rxperf_abort_op_not_supported); goto call_complete; case -EIO: pr_err("Call %u in bad state %u\n", call->debug_id, call->state); fallthrough; case -ENODATA: case -EBADMSG: case -EMSGSIZE: case -ENOMEM: case -EFAULT: rxrpc_kernel_abort_call(rxperf_socket, call->rxcall, RXGEN_SS_UNMARSHAL, ret, rxperf_abort_unmarshal_error); goto call_complete; default: rxrpc_kernel_abort_call(rxperf_socket, call->rxcall, RX_CALL_DEAD, ret, rxperf_abort_general_error); goto call_complete; } } call_complete: rxperf_set_call_complete(call, ret, remote_abort); /* The call may have been requeued */ rxrpc_kernel_shutdown_call(rxperf_socket, call->rxcall); rxrpc_kernel_put_call(rxperf_socket, call->rxcall); cancel_work(&call->work); kfree(call); } /* * Extract a piece of data from the received data socket buffers. */ static int rxperf_extract_data(struct rxperf_call *call, bool want_more) { u32 remote_abort = 0; int ret; ret = rxrpc_kernel_recv_data(rxperf_socket, call->rxcall, &call->iter, &call->iov_len, want_more, &remote_abort, &call->service_id); pr_debug("Extract i=%zu l=%zu m=%u ret=%d\n", iov_iter_count(&call->iter), call->iov_len, want_more, ret); if (ret == 0 || ret == -EAGAIN) return ret; if (ret == 1) { switch (call->state) { case RXPERF_CALL_SV_AWAIT_REQUEST: rxperf_set_call_state(call, RXPERF_CALL_SV_REPLYING); break; case RXPERF_CALL_COMPLETE: pr_debug("premature completion %d", call->error); return call->error; default: break; } return 0; } rxperf_set_call_complete(call, ret, remote_abort); return ret; } /* * Grab the operation ID from an incoming manager call. */ static int rxperf_deliver_param_block(struct rxperf_call *call) { u32 version; int ret; /* Extract the parameter block */ ret = rxperf_extract_data(call, true); if (ret < 0) return ret; version = ntohl(call->params.version); call->operation_id = ntohl(call->params.type); call->deliver = rxperf_deliver_request; if (version != RX_PERF_VERSION) { pr_info("Version mismatch %x\n", version); return -ENOTSUPP; } switch (call->operation_id) { case RX_PERF_SEND: call->type = "send"; call->reply_len = 0; call->iov_len = 4; /* Expect req size */ break; case RX_PERF_RECV: call->type = "recv"; call->req_len = 0; call->iov_len = 4; /* Expect reply size */ break; case RX_PERF_RPC: call->type = "rpc"; call->iov_len = 8; /* Expect req size and reply size */ break; case RX_PERF_FILE: call->type = "file"; fallthrough; default: return -EOPNOTSUPP; } rxperf_set_call_state(call, RXPERF_CALL_SV_AWAIT_REQUEST); return call->deliver(call); } /* * Deliver the request data. */ static int rxperf_deliver_request(struct rxperf_call *call) { int ret; switch (call->unmarshal) { case 0: call->kvec[0].iov_len = call->iov_len; call->kvec[0].iov_base = call->tmp; iov_iter_kvec(&call->iter, READ, call->kvec, 1, call->iov_len); call->unmarshal++; fallthrough; case 1: ret = rxperf_extract_data(call, true); if (ret < 0) return ret; switch (call->operation_id) { case RX_PERF_SEND: call->type = "send"; call->req_len = ntohl(call->tmp[0]); call->reply_len = 0; break; case RX_PERF_RECV: call->type = "recv"; call->req_len = 0; call->reply_len = ntohl(call->tmp[0]); break; case RX_PERF_RPC: call->type = "rpc"; call->req_len = ntohl(call->tmp[0]); call->reply_len = ntohl(call->tmp[1]); break; default: pr_info("Can't parse extra params\n"); return -EIO; } pr_debug("CALL op=%s rq=%zx rp=%zx\n", call->type, call->req_len, call->reply_len); call->iov_len = call->req_len; iov_iter_discard(&call->iter, READ, call->req_len); call->unmarshal++; fallthrough; case 2: ret = rxperf_extract_data(call, false); if (ret < 0) return ret; call->unmarshal++; fallthrough; default: return 0; } } /* * Process a call for which we've received the request. */ static int rxperf_process_call(struct rxperf_call *call) { struct msghdr msg = {}; struct bio_vec bv; struct kvec iov[1]; ssize_t n; size_t reply_len = call->reply_len, len; rxrpc_kernel_set_tx_length(rxperf_socket, call->rxcall, reply_len + sizeof(rxperf_magic_cookie)); while (reply_len > 0) { len = min_t(size_t, reply_len, PAGE_SIZE); bvec_set_page(&bv, ZERO_PAGE(0), len, 0); iov_iter_bvec(&msg.msg_iter, WRITE, &bv, 1, len); msg.msg_flags = MSG_MORE; n = rxrpc_kernel_send_data(rxperf_socket, call->rxcall, &msg, len, rxperf_notify_end_reply_tx); if (n < 0) return n; if (n == 0) return -EIO; reply_len -= n; } len = sizeof(rxperf_magic_cookie); iov[0].iov_base = (void *)rxperf_magic_cookie; iov[0].iov_len = len; iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len); msg.msg_flags = 0; n = rxrpc_kernel_send_data(rxperf_socket, call->rxcall, &msg, len, rxperf_notify_end_reply_tx); if (n >= 0) return 0; /* Success */ if (n == -ENOMEM) rxrpc_kernel_abort_call(rxperf_socket, call->rxcall, RXGEN_SS_MARSHAL, -ENOMEM, rxperf_abort_oom); return n; } /* * Add a key to the security keyring. */ static int rxperf_add_key(struct key *keyring) { key_ref_t kref; int ret; kref = key_create_or_update(make_key_ref(keyring, true), "rxrpc_s", __stringify(RX_PERF_SERVICE) ":2", secret, sizeof(secret), KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH | KEY_USR_VIEW, KEY_ALLOC_NOT_IN_QUOTA); if (IS_ERR(kref)) { pr_err("Can't allocate rxperf server key: %ld\n", PTR_ERR(kref)); return PTR_ERR(kref); } ret = key_link(keyring, key_ref_to_ptr(kref)); if (ret < 0) pr_err("Can't link rxperf server key: %d\n", ret); key_ref_put(kref); return ret; } /* * Initialise the rxperf server. */ static int __init rxperf_init(void) { struct key *keyring; int ret = -ENOMEM; pr_info("Server registering\n"); rxperf_workqueue = alloc_workqueue("rxperf", 0, 0); if (!rxperf_workqueue) goto error_workqueue; keyring = keyring_alloc("rxperf_server", GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(), KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH | KEY_POS_WRITE | KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH | KEY_USR_WRITE | KEY_OTH_VIEW | KEY_OTH_READ | KEY_OTH_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); if (IS_ERR(keyring)) { pr_err("Can't allocate rxperf server keyring: %ld\n", PTR_ERR(keyring)); goto error_keyring; } rxperf_sec_keyring = keyring; ret = rxperf_add_key(keyring); if (ret < 0) goto error_key; ret = rxperf_open_socket(); if (ret < 0) goto error_socket; return 0; error_socket: error_key: key_put(rxperf_sec_keyring); error_keyring: destroy_workqueue(rxperf_workqueue); rcu_barrier(); error_workqueue: pr_err("Failed to register: %d\n", ret); return ret; } late_initcall(rxperf_init); /* Must be called after net/ to create socket */ static void __exit rxperf_exit(void) { pr_info("Server unregistering.\n"); rxperf_close_socket(); key_put(rxperf_sec_keyring); destroy_workqueue(rxperf_workqueue); rcu_barrier(); } module_exit(rxperf_exit);
linux-master
net/rxrpc/rxperf.c
// SPDX-License-Identifier: GPL-2.0-or-later /* RxRPC packet transmission * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/net.h> #include <linux/gfp.h> #include <linux/skbuff.h> #include <linux/export.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include <net/udp.h> #include "ar-internal.h" extern int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len); static ssize_t do_udp_sendmsg(struct socket *socket, struct msghdr *msg, size_t len) { struct sockaddr *sa = msg->msg_name; struct sock *sk = socket->sk; if (IS_ENABLED(CONFIG_AF_RXRPC_IPV6)) { if (sa->sa_family == AF_INET6) { if (sk->sk_family != AF_INET6) { pr_warn("AF_INET6 address on AF_INET socket\n"); return -ENOPROTOOPT; } return udpv6_sendmsg(sk, msg, len); } } return udp_sendmsg(sk, msg, len); } struct rxrpc_abort_buffer { struct rxrpc_wire_header whdr; __be32 abort_code; }; static const char rxrpc_keepalive_string[] = ""; /* * Increase Tx backoff on transmission failure and clear it on success. */ static void rxrpc_tx_backoff(struct rxrpc_call *call, int ret) { if (ret < 0) { u16 tx_backoff = READ_ONCE(call->tx_backoff); if (tx_backoff < HZ) WRITE_ONCE(call->tx_backoff, tx_backoff + 1); } else { WRITE_ONCE(call->tx_backoff, 0); } } /* * Arrange for a keepalive ping a certain time after we last transmitted. This * lets the far side know we're still interested in this call and helps keep * the route through any intervening firewall open. * * Receiving a response to the ping will prevent the ->expect_rx_by timer from * expiring. */ static void rxrpc_set_keepalive(struct rxrpc_call *call) { unsigned long now = jiffies, keepalive_at = call->next_rx_timo / 6; keepalive_at += now; WRITE_ONCE(call->keepalive_at, keepalive_at); rxrpc_reduce_call_timer(call, keepalive_at, now, rxrpc_timer_set_for_keepalive); } /* * Fill out an ACK packet. */ static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn, struct rxrpc_call *call, struct rxrpc_txbuf *txb, u16 *_rwind) { struct rxrpc_ackinfo ackinfo; unsigned int qsize, sack, wrap, to; rxrpc_seq_t window, wtop; int rsize; u32 mtu, jmax; u8 *ackp = txb->acks; call->ackr_nr_unacked = 0; atomic_set(&call->ackr_nr_consumed, 0); rxrpc_inc_stat(call->rxnet, stat_tx_ack_fill); clear_bit(RXRPC_CALL_RX_IS_IDLE, &call->flags); window = call->ackr_window; wtop = call->ackr_wtop; sack = call->ackr_sack_base % RXRPC_SACK_SIZE; txb->ack.firstPacket = htonl(window); txb->ack.nAcks = wtop - window; if (after(wtop, window)) { wrap = RXRPC_SACK_SIZE - sack; to = min_t(unsigned int, txb->ack.nAcks, RXRPC_SACK_SIZE); if (sack + txb->ack.nAcks <= RXRPC_SACK_SIZE) { memcpy(txb->acks, call->ackr_sack_table + sack, txb->ack.nAcks); } else { memcpy(txb->acks, call->ackr_sack_table + sack, wrap); memcpy(txb->acks + wrap, call->ackr_sack_table, to - wrap); } ackp += to; } else if (before(wtop, window)) { pr_warn("ack window backward %x %x", window, wtop); } else if (txb->ack.reason == RXRPC_ACK_DELAY) { txb->ack.reason = RXRPC_ACK_IDLE; } mtu = conn->peer->if_mtu; mtu -= conn->peer->hdrsize; jmax = rxrpc_rx_jumbo_max; qsize = (window - 1) - call->rx_consumed; rsize = max_t(int, call->rx_winsize - qsize, 0); *_rwind = rsize; ackinfo.rxMTU = htonl(rxrpc_rx_mtu); ackinfo.maxMTU = htonl(mtu); ackinfo.rwind = htonl(rsize); ackinfo.jumbo_max = htonl(jmax); *ackp++ = 0; *ackp++ = 0; *ackp++ = 0; memcpy(ackp, &ackinfo, sizeof(ackinfo)); return txb->ack.nAcks + 3 + sizeof(ackinfo); } /* * Record the beginning of an RTT probe. */ static int rxrpc_begin_rtt_probe(struct rxrpc_call *call, rxrpc_serial_t serial, enum rxrpc_rtt_tx_trace why) { unsigned long avail = call->rtt_avail; int rtt_slot = 9; if (!(avail & RXRPC_CALL_RTT_AVAIL_MASK)) goto no_slot; rtt_slot = __ffs(avail & RXRPC_CALL_RTT_AVAIL_MASK); if (!test_and_clear_bit(rtt_slot, &call->rtt_avail)) goto no_slot; call->rtt_serial[rtt_slot] = serial; call->rtt_sent_at[rtt_slot] = ktime_get_real(); smp_wmb(); /* Write data before avail bit */ set_bit(rtt_slot + RXRPC_CALL_RTT_PEND_SHIFT, &call->rtt_avail); trace_rxrpc_rtt_tx(call, why, rtt_slot, serial); return rtt_slot; no_slot: trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_no_slot, rtt_slot, serial); return -1; } /* * Cancel an RTT probe. */ static void rxrpc_cancel_rtt_probe(struct rxrpc_call *call, rxrpc_serial_t serial, int rtt_slot) { if (rtt_slot != -1) { clear_bit(rtt_slot + RXRPC_CALL_RTT_PEND_SHIFT, &call->rtt_avail); smp_wmb(); /* Clear pending bit before setting slot */ set_bit(rtt_slot, &call->rtt_avail); trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_cancel, rtt_slot, serial); } } /* * Transmit an ACK packet. */ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb) { struct rxrpc_connection *conn; struct msghdr msg; struct kvec iov[1]; rxrpc_serial_t serial; size_t len, n; int ret, rtt_slot = -1; u16 rwind; if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) return -ECONNRESET; conn = call->conn; msg.msg_name = &call->peer->srx.transport; msg.msg_namelen = call->peer->srx.transport_len; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; if (txb->ack.reason == RXRPC_ACK_PING) txb->wire.flags |= RXRPC_REQUEST_ACK; n = rxrpc_fill_out_ack(conn, call, txb, &rwind); if (n == 0) return 0; iov[0].iov_base = &txb->wire; iov[0].iov_len = sizeof(txb->wire) + sizeof(txb->ack) + n; len = iov[0].iov_len; serial = atomic_inc_return(&conn->serial); txb->wire.serial = htonl(serial); trace_rxrpc_tx_ack(call->debug_id, serial, ntohl(txb->ack.firstPacket), ntohl(txb->ack.serial), txb->ack.reason, txb->ack.nAcks, rwind); if (txb->ack.reason == RXRPC_ACK_PING) rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_ping); rxrpc_inc_stat(call->rxnet, stat_tx_ack_send); /* Grab the highest received seq as late as possible */ txb->ack.previousPacket = htonl(call->rx_highest_seq); iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len); ret = do_udp_sendmsg(conn->local->socket, &msg, len); call->peer->last_tx_at = ktime_get_seconds(); if (ret < 0) { trace_rxrpc_tx_fail(call->debug_id, serial, ret, rxrpc_tx_point_call_ack); } else { trace_rxrpc_tx_packet(call->debug_id, &txb->wire, rxrpc_tx_point_call_ack); if (txb->wire.flags & RXRPC_REQUEST_ACK) call->peer->rtt_last_req = ktime_get_real(); } rxrpc_tx_backoff(call, ret); if (!__rxrpc_call_is_complete(call)) { if (ret < 0) rxrpc_cancel_rtt_probe(call, serial, rtt_slot); rxrpc_set_keepalive(call); } return ret; } /* * Send an ABORT call packet. */ int rxrpc_send_abort_packet(struct rxrpc_call *call) { struct rxrpc_connection *conn; struct rxrpc_abort_buffer pkt; struct msghdr msg; struct kvec iov[1]; rxrpc_serial_t serial; int ret; /* Don't bother sending aborts for a client call once the server has * hard-ACK'd all of its request data. After that point, we're not * going to stop the operation proceeding, and whilst we might limit * the reply, it's not worth it if we can send a new call on the same * channel instead, thereby closing off this call. */ if (rxrpc_is_client_call(call) && test_bit(RXRPC_CALL_TX_ALL_ACKED, &call->flags)) return 0; if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) return -ECONNRESET; conn = call->conn; msg.msg_name = &call->peer->srx.transport; msg.msg_namelen = call->peer->srx.transport_len; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; pkt.whdr.epoch = htonl(conn->proto.epoch); pkt.whdr.cid = htonl(call->cid); pkt.whdr.callNumber = htonl(call->call_id); pkt.whdr.seq = 0; pkt.whdr.type = RXRPC_PACKET_TYPE_ABORT; pkt.whdr.flags = conn->out_clientflag; pkt.whdr.userStatus = 0; pkt.whdr.securityIndex = call->security_ix; pkt.whdr._rsvd = 0; pkt.whdr.serviceId = htons(call->dest_srx.srx_service); pkt.abort_code = htonl(call->abort_code); iov[0].iov_base = &pkt; iov[0].iov_len = sizeof(pkt); serial = atomic_inc_return(&conn->serial); pkt.whdr.serial = htonl(serial); iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, sizeof(pkt)); ret = do_udp_sendmsg(conn->local->socket, &msg, sizeof(pkt)); conn->peer->last_tx_at = ktime_get_seconds(); if (ret < 0) trace_rxrpc_tx_fail(call->debug_id, serial, ret, rxrpc_tx_point_call_abort); else trace_rxrpc_tx_packet(call->debug_id, &pkt.whdr, rxrpc_tx_point_call_abort); rxrpc_tx_backoff(call, ret); return ret; } /* * send a packet through the transport endpoint */ int rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb) { enum rxrpc_req_ack_trace why; struct rxrpc_connection *conn = call->conn; struct msghdr msg; struct kvec iov[1]; rxrpc_serial_t serial; size_t len; int ret, rtt_slot = -1; _enter("%x,{%d}", txb->seq, txb->len); /* Each transmission of a Tx packet needs a new serial number */ serial = atomic_inc_return(&conn->serial); txb->wire.serial = htonl(serial); if (test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) && txb->seq == 1) txb->wire.userStatus = RXRPC_USERSTATUS_SERVICE_UPGRADE; iov[0].iov_base = &txb->wire; iov[0].iov_len = sizeof(txb->wire) + txb->len; len = iov[0].iov_len; iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len); msg.msg_name = &call->peer->srx.transport; msg.msg_namelen = call->peer->srx.transport_len; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; /* If our RTT cache needs working on, request an ACK. Also request * ACKs if a DATA packet appears to have been lost. * * However, we mustn't request an ACK on the last reply packet of a * service call, lest OpenAFS incorrectly send us an ACK with some * soft-ACKs in it and then never follow up with a proper hard ACK. */ if (txb->wire.flags & RXRPC_REQUEST_ACK) why = rxrpc_reqack_already_on; else if (test_bit(RXRPC_TXBUF_LAST, &txb->flags) && rxrpc_sending_to_client(txb)) why = rxrpc_reqack_no_srv_last; else if (test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events)) why = rxrpc_reqack_ack_lost; else if (test_bit(RXRPC_TXBUF_RESENT, &txb->flags)) why = rxrpc_reqack_retrans; else if (call->cong_mode == RXRPC_CALL_SLOW_START && call->cong_cwnd <= 2) why = rxrpc_reqack_slow_start; else if (call->tx_winsize <= 2) why = rxrpc_reqack_small_txwin; else if (call->peer->rtt_count < 3 && txb->seq & 1) why = rxrpc_reqack_more_rtt; else if (ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), ktime_get_real())) why = rxrpc_reqack_old_rtt; else goto dont_set_request_ack; rxrpc_inc_stat(call->rxnet, stat_why_req_ack[why]); trace_rxrpc_req_ack(call->debug_id, txb->seq, why); if (why != rxrpc_reqack_no_srv_last) txb->wire.flags |= RXRPC_REQUEST_ACK; dont_set_request_ack: if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) { static int lose; if ((lose++ & 7) == 7) { ret = 0; trace_rxrpc_tx_data(call, txb->seq, serial, txb->wire.flags, test_bit(RXRPC_TXBUF_RESENT, &txb->flags), true); goto done; } } trace_rxrpc_tx_data(call, txb->seq, serial, txb->wire.flags, test_bit(RXRPC_TXBUF_RESENT, &txb->flags), false); /* Track what we've attempted to transmit at least once so that the * retransmission algorithm doesn't try to resend what we haven't sent * yet. However, this can race as we can receive an ACK before we get * to this point. But, OTOH, if we won't get an ACK mentioning this * packet unless the far side received it (though it could have * discarded it anyway and NAK'd it). */ cmpxchg(&call->tx_transmitted, txb->seq - 1, txb->seq); /* send the packet with the don't fragment bit set if we currently * think it's small enough */ if (txb->len >= call->peer->maxdata) goto send_fragmentable; txb->last_sent = ktime_get_real(); if (txb->wire.flags & RXRPC_REQUEST_ACK) rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_data); /* send the packet by UDP * - returns -EMSGSIZE if UDP would have to fragment the packet * to go out of the interface * - in which case, we'll have processed the ICMP error * message and update the peer record */ rxrpc_inc_stat(call->rxnet, stat_tx_data_send); ret = do_udp_sendmsg(conn->local->socket, &msg, len); conn->peer->last_tx_at = ktime_get_seconds(); if (ret < 0) { rxrpc_inc_stat(call->rxnet, stat_tx_data_send_fail); rxrpc_cancel_rtt_probe(call, serial, rtt_slot); trace_rxrpc_tx_fail(call->debug_id, serial, ret, rxrpc_tx_point_call_data_nofrag); } else { trace_rxrpc_tx_packet(call->debug_id, &txb->wire, rxrpc_tx_point_call_data_nofrag); } rxrpc_tx_backoff(call, ret); if (ret == -EMSGSIZE) goto send_fragmentable; done: if (ret >= 0) { call->tx_last_sent = txb->last_sent; if (txb->wire.flags & RXRPC_REQUEST_ACK) { call->peer->rtt_last_req = txb->last_sent; if (call->peer->rtt_count > 1) { unsigned long nowj = jiffies, ack_lost_at; ack_lost_at = rxrpc_get_rto_backoff(call->peer, false); ack_lost_at += nowj; WRITE_ONCE(call->ack_lost_at, ack_lost_at); rxrpc_reduce_call_timer(call, ack_lost_at, nowj, rxrpc_timer_set_for_lost_ack); } } if (txb->seq == 1 && !test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER, &call->flags)) { unsigned long nowj = jiffies, expect_rx_by; expect_rx_by = nowj + call->next_rx_timo; WRITE_ONCE(call->expect_rx_by, expect_rx_by); rxrpc_reduce_call_timer(call, expect_rx_by, nowj, rxrpc_timer_set_for_normal); } rxrpc_set_keepalive(call); } else { /* Cancel the call if the initial transmission fails, * particularly if that's due to network routing issues that * aren't going away anytime soon. The layer above can arrange * the retransmission. */ if (!test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER, &call->flags)) rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, RX_USER_ABORT, ret); } _leave(" = %d [%u]", ret, call->peer->maxdata); return ret; send_fragmentable: /* attempt to send this message with fragmentation enabled */ _debug("send fragment"); txb->last_sent = ktime_get_real(); if (txb->wire.flags & RXRPC_REQUEST_ACK) rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_data); switch (conn->local->srx.transport.family) { case AF_INET6: case AF_INET: ip_sock_set_mtu_discover(conn->local->socket->sk, IP_PMTUDISC_DONT); rxrpc_inc_stat(call->rxnet, stat_tx_data_send_frag); ret = do_udp_sendmsg(conn->local->socket, &msg, len); conn->peer->last_tx_at = ktime_get_seconds(); ip_sock_set_mtu_discover(conn->local->socket->sk, IP_PMTUDISC_DO); break; default: BUG(); } if (ret < 0) { rxrpc_inc_stat(call->rxnet, stat_tx_data_send_fail); rxrpc_cancel_rtt_probe(call, serial, rtt_slot); trace_rxrpc_tx_fail(call->debug_id, serial, ret, rxrpc_tx_point_call_data_frag); } else { trace_rxrpc_tx_packet(call->debug_id, &txb->wire, rxrpc_tx_point_call_data_frag); } rxrpc_tx_backoff(call, ret); goto done; } /* * Transmit a connection-level abort. */ void rxrpc_send_conn_abort(struct rxrpc_connection *conn) { struct rxrpc_wire_header whdr; struct msghdr msg; struct kvec iov[2]; __be32 word; size_t len; u32 serial; int ret; msg.msg_name = &conn->peer->srx.transport; msg.msg_namelen = conn->peer->srx.transport_len; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; whdr.epoch = htonl(conn->proto.epoch); whdr.cid = htonl(conn->proto.cid); whdr.callNumber = 0; whdr.seq = 0; whdr.type = RXRPC_PACKET_TYPE_ABORT; whdr.flags = conn->out_clientflag; whdr.userStatus = 0; whdr.securityIndex = conn->security_ix; whdr._rsvd = 0; whdr.serviceId = htons(conn->service_id); word = htonl(conn->abort_code); iov[0].iov_base = &whdr; iov[0].iov_len = sizeof(whdr); iov[1].iov_base = &word; iov[1].iov_len = sizeof(word); len = iov[0].iov_len + iov[1].iov_len; serial = atomic_inc_return(&conn->serial); whdr.serial = htonl(serial); iov_iter_kvec(&msg.msg_iter, WRITE, iov, 2, len); ret = do_udp_sendmsg(conn->local->socket, &msg, len); if (ret < 0) { trace_rxrpc_tx_fail(conn->debug_id, serial, ret, rxrpc_tx_point_conn_abort); _debug("sendmsg failed: %d", ret); return; } trace_rxrpc_tx_packet(conn->debug_id, &whdr, rxrpc_tx_point_conn_abort); conn->peer->last_tx_at = ktime_get_seconds(); } /* * Reject a packet through the local endpoint. */ void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb) { struct rxrpc_wire_header whdr; struct sockaddr_rxrpc srx; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct msghdr msg; struct kvec iov[2]; size_t size; __be32 code; int ret, ioc; rxrpc_see_skb(skb, rxrpc_skb_see_reject); iov[0].iov_base = &whdr; iov[0].iov_len = sizeof(whdr); iov[1].iov_base = &code; iov[1].iov_len = sizeof(code); msg.msg_name = &srx.transport; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; memset(&whdr, 0, sizeof(whdr)); switch (skb->mark) { case RXRPC_SKB_MARK_REJECT_BUSY: whdr.type = RXRPC_PACKET_TYPE_BUSY; size = sizeof(whdr); ioc = 1; break; case RXRPC_SKB_MARK_REJECT_ABORT: whdr.type = RXRPC_PACKET_TYPE_ABORT; code = htonl(skb->priority); size = sizeof(whdr) + sizeof(code); ioc = 2; break; default: return; } if (rxrpc_extract_addr_from_skb(&srx, skb) == 0) { msg.msg_namelen = srx.transport_len; whdr.epoch = htonl(sp->hdr.epoch); whdr.cid = htonl(sp->hdr.cid); whdr.callNumber = htonl(sp->hdr.callNumber); whdr.serviceId = htons(sp->hdr.serviceId); whdr.flags = sp->hdr.flags; whdr.flags ^= RXRPC_CLIENT_INITIATED; whdr.flags &= RXRPC_CLIENT_INITIATED; iov_iter_kvec(&msg.msg_iter, WRITE, iov, ioc, size); ret = do_udp_sendmsg(local->socket, &msg, size); if (ret < 0) trace_rxrpc_tx_fail(local->debug_id, 0, ret, rxrpc_tx_point_reject); else trace_rxrpc_tx_packet(local->debug_id, &whdr, rxrpc_tx_point_reject); } } /* * Send a VERSION reply to a peer as a keepalive. */ void rxrpc_send_keepalive(struct rxrpc_peer *peer) { struct rxrpc_wire_header whdr; struct msghdr msg; struct kvec iov[2]; size_t len; int ret; _enter(""); msg.msg_name = &peer->srx.transport; msg.msg_namelen = peer->srx.transport_len; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; whdr.epoch = htonl(peer->local->rxnet->epoch); whdr.cid = 0; whdr.callNumber = 0; whdr.seq = 0; whdr.serial = 0; whdr.type = RXRPC_PACKET_TYPE_VERSION; /* Not client-initiated */ whdr.flags = RXRPC_LAST_PACKET; whdr.userStatus = 0; whdr.securityIndex = 0; whdr._rsvd = 0; whdr.serviceId = 0; iov[0].iov_base = &whdr; iov[0].iov_len = sizeof(whdr); iov[1].iov_base = (char *)rxrpc_keepalive_string; iov[1].iov_len = sizeof(rxrpc_keepalive_string); len = iov[0].iov_len + iov[1].iov_len; iov_iter_kvec(&msg.msg_iter, WRITE, iov, 2, len); ret = do_udp_sendmsg(peer->local->socket, &msg, len); if (ret < 0) trace_rxrpc_tx_fail(peer->debug_id, 0, ret, rxrpc_tx_point_version_keepalive); else trace_rxrpc_tx_packet(peer->debug_id, &whdr, rxrpc_tx_point_version_keepalive); peer->last_tx_at = ktime_get_seconds(); _leave(""); } /* * Schedule an instant Tx resend. */ static inline void rxrpc_instant_resend(struct rxrpc_call *call, struct rxrpc_txbuf *txb) { if (!__rxrpc_call_is_complete(call)) kdebug("resend"); } /* * Transmit one packet. */ void rxrpc_transmit_one(struct rxrpc_call *call, struct rxrpc_txbuf *txb) { int ret; ret = rxrpc_send_data_packet(call, txb); if (ret < 0) { switch (ret) { case -ENETUNREACH: case -EHOSTUNREACH: case -ECONNREFUSED: rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret); break; default: _debug("need instant resend %d", ret); rxrpc_instant_resend(call, txb); } } else { unsigned long now = jiffies; unsigned long resend_at = now + call->peer->rto_j; WRITE_ONCE(call->resend_at, resend_at); rxrpc_reduce_call_timer(call, resend_at, now, rxrpc_timer_set_for_send); } }
linux-master
net/rxrpc/output.c
// SPDX-License-Identifier: GPL-2.0-or-later /* rxrpc network namespace handling. * * Copyright (C) 2017 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) */ #include <linux/proc_fs.h> #include "ar-internal.h" unsigned int rxrpc_net_id; static void rxrpc_service_conn_reap_timeout(struct timer_list *timer) { struct rxrpc_net *rxnet = container_of(timer, struct rxrpc_net, service_conn_reap_timer); if (rxnet->live) rxrpc_queue_work(&rxnet->service_conn_reaper); } static void rxrpc_peer_keepalive_timeout(struct timer_list *timer) { struct rxrpc_net *rxnet = container_of(timer, struct rxrpc_net, peer_keepalive_timer); if (rxnet->live) rxrpc_queue_work(&rxnet->peer_keepalive_work); } /* * Initialise a per-network namespace record. */ static __net_init int rxrpc_init_net(struct net *net) { struct rxrpc_net *rxnet = rxrpc_net(net); int ret, i; rxnet->live = true; get_random_bytes(&rxnet->epoch, sizeof(rxnet->epoch)); rxnet->epoch |= RXRPC_RANDOM_EPOCH; INIT_LIST_HEAD(&rxnet->calls); spin_lock_init(&rxnet->call_lock); atomic_set(&rxnet->nr_calls, 1); atomic_set(&rxnet->nr_conns, 1); INIT_LIST_HEAD(&rxnet->conn_proc_list); INIT_LIST_HEAD(&rxnet->service_conns); rwlock_init(&rxnet->conn_lock); INIT_WORK(&rxnet->service_conn_reaper, rxrpc_service_connection_reaper); timer_setup(&rxnet->service_conn_reap_timer, rxrpc_service_conn_reap_timeout, 0); atomic_set(&rxnet->nr_client_conns, 0); INIT_HLIST_HEAD(&rxnet->local_endpoints); mutex_init(&rxnet->local_mutex); hash_init(rxnet->peer_hash); spin_lock_init(&rxnet->peer_hash_lock); for (i = 0; i < ARRAY_SIZE(rxnet->peer_keepalive); i++) INIT_LIST_HEAD(&rxnet->peer_keepalive[i]); INIT_LIST_HEAD(&rxnet->peer_keepalive_new); timer_setup(&rxnet->peer_keepalive_timer, rxrpc_peer_keepalive_timeout, 0); INIT_WORK(&rxnet->peer_keepalive_work, rxrpc_peer_keepalive_worker); rxnet->peer_keepalive_base = ktime_get_seconds(); ret = -ENOMEM; rxnet->proc_net = proc_net_mkdir(net, "rxrpc", net->proc_net); if (!rxnet->proc_net) goto err_proc; proc_create_net("calls", 0444, rxnet->proc_net, &rxrpc_call_seq_ops, sizeof(struct seq_net_private)); proc_create_net("conns", 0444, rxnet->proc_net, &rxrpc_connection_seq_ops, sizeof(struct seq_net_private)); proc_create_net("peers", 0444, rxnet->proc_net, &rxrpc_peer_seq_ops, sizeof(struct seq_net_private)); proc_create_net("locals", 0444, rxnet->proc_net, &rxrpc_local_seq_ops, sizeof(struct seq_net_private)); proc_create_net_single_write("stats", S_IFREG | 0644, rxnet->proc_net, rxrpc_stats_show, rxrpc_stats_clear, NULL); return 0; err_proc: rxnet->live = false; return ret; } /* * Clean up a per-network namespace record. */ static __net_exit void rxrpc_exit_net(struct net *net) { struct rxrpc_net *rxnet = rxrpc_net(net); rxnet->live = false; del_timer_sync(&rxnet->peer_keepalive_timer); cancel_work_sync(&rxnet->peer_keepalive_work); /* Remove the timer again as the worker may have restarted it. */ del_timer_sync(&rxnet->peer_keepalive_timer); rxrpc_destroy_all_calls(rxnet); rxrpc_destroy_all_connections(rxnet); rxrpc_destroy_all_peers(rxnet); rxrpc_destroy_all_locals(rxnet); proc_remove(rxnet->proc_net); } struct pernet_operations rxrpc_net_ops = { .init = rxrpc_init_net, .exit = rxrpc_exit_net, .id = &rxrpc_net_id, .size = sizeof(struct rxrpc_net), };
linux-master
net/rxrpc/net_ns.c
// SPDX-License-Identifier: GPL-2.0-only /* * File: sysctl.c * * Phonet /proc/sys/net/phonet interface implementation * * Copyright (C) 2008 Nokia Corporation. * * Author: Rémi Denis-Courmont */ #include <linux/seqlock.h> #include <linux/sysctl.h> #include <linux/errno.h> #include <linux/init.h> #include <net/sock.h> #include <linux/phonet.h> #include <net/phonet/phonet.h> #define DYNAMIC_PORT_MIN 0x40 #define DYNAMIC_PORT_MAX 0x7f static DEFINE_SEQLOCK(local_port_range_lock); static int local_port_range_min[2] = {0, 0}; static int local_port_range_max[2] = {1023, 1023}; static int local_port_range[2] = {DYNAMIC_PORT_MIN, DYNAMIC_PORT_MAX}; static struct ctl_table_header *phonet_table_hrd; static void set_local_port_range(int range[2]) { write_seqlock(&local_port_range_lock); local_port_range[0] = range[0]; local_port_range[1] = range[1]; write_sequnlock(&local_port_range_lock); } void phonet_get_local_port_range(int *min, int *max) { unsigned int seq; do { seq = read_seqbegin(&local_port_range_lock); if (min) *min = local_port_range[0]; if (max) *max = local_port_range[1]; } while (read_seqretry(&local_port_range_lock, seq)); } static int proc_local_port_range(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { int ret; int range[2] = {local_port_range[0], local_port_range[1]}; struct ctl_table tmp = { .data = &range, .maxlen = sizeof(range), .mode = table->mode, .extra1 = &local_port_range_min, .extra2 = &local_port_range_max, }; ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); if (write && ret == 0) { if (range[1] < range[0]) ret = -EINVAL; else set_local_port_range(range); } return ret; } static struct ctl_table phonet_table[] = { { .procname = "local_port_range", .data = &local_port_range, .maxlen = sizeof(local_port_range), .mode = 0644, .proc_handler = proc_local_port_range, }, { } }; int __init phonet_sysctl_init(void) { phonet_table_hrd = register_net_sysctl(&init_net, "net/phonet", phonet_table); return phonet_table_hrd == NULL ? -ENOMEM : 0; } void phonet_sysctl_exit(void) { unregister_net_sysctl_table(phonet_table_hrd); }
linux-master
net/phonet/sysctl.c
// SPDX-License-Identifier: GPL-2.0-only /* * File: pn_netlink.c * * Phonet netlink interface * * Copyright (C) 2008 Nokia Corporation. * * Authors: Sakari Ailus <[email protected]> * Remi Denis-Courmont */ #include <linux/kernel.h> #include <linux/netlink.h> #include <linux/phonet.h> #include <linux/slab.h> #include <net/sock.h> #include <net/phonet/pn_dev.h> /* Device address handling */ static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, u32 portid, u32 seq, int event); void phonet_address_notify(int event, struct net_device *dev, u8 addr) { struct sk_buff *skb; int err = -ENOBUFS; skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + nla_total_size(1), GFP_KERNEL); if (skb == NULL) goto errout; err = fill_addr(skb, dev, addr, 0, 0, event); if (err < 0) { WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; } rtnl_notify(skb, dev_net(dev), 0, RTNLGRP_PHONET_IFADDR, NULL, GFP_KERNEL); return; errout: rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_IFADDR, err); } static const struct nla_policy ifa_phonet_policy[IFA_MAX+1] = { [IFA_LOCAL] = { .type = NLA_U8 }, }; static int addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct nlattr *tb[IFA_MAX+1]; struct net_device *dev; struct ifaddrmsg *ifm; int err; u8 pnaddr; if (!netlink_capable(skb, CAP_NET_ADMIN)) return -EPERM; if (!netlink_capable(skb, CAP_SYS_ADMIN)) return -EPERM; ASSERT_RTNL(); err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_phonet_policy, extack); if (err < 0) return err; ifm = nlmsg_data(nlh); if (tb[IFA_LOCAL] == NULL) return -EINVAL; pnaddr = nla_get_u8(tb[IFA_LOCAL]); if (pnaddr & 3) /* Phonet addresses only have 6 high-order bits */ return -EINVAL; dev = __dev_get_by_index(net, ifm->ifa_index); if (dev == NULL) return -ENODEV; if (nlh->nlmsg_type == RTM_NEWADDR) err = phonet_address_add(dev, pnaddr); else err = phonet_address_del(dev, pnaddr); if (!err) phonet_address_notify(nlh->nlmsg_type, dev, pnaddr); return err; } static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, u32 portid, u32 seq, int event) { struct ifaddrmsg *ifm; struct nlmsghdr *nlh; nlh = nlmsg_put(skb, portid, seq, event, sizeof(*ifm), 0); if (nlh == NULL) return -EMSGSIZE; ifm = nlmsg_data(nlh); ifm->ifa_family = AF_PHONET; ifm->ifa_prefixlen = 0; ifm->ifa_flags = IFA_F_PERMANENT; ifm->ifa_scope = RT_SCOPE_LINK; ifm->ifa_index = dev->ifindex; if (nla_put_u8(skb, IFA_LOCAL, addr)) goto nla_put_failure; nlmsg_end(skb, nlh); return 0; nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static int getaddr_dumpit(struct sk_buff *skb, struct netlink_callback *cb) { struct phonet_device_list *pndevs; struct phonet_device *pnd; int dev_idx = 0, dev_start_idx = cb->args[0]; int addr_idx = 0, addr_start_idx = cb->args[1]; pndevs = phonet_device_list(sock_net(skb->sk)); rcu_read_lock(); list_for_each_entry_rcu(pnd, &pndevs->list, list) { u8 addr; if (dev_idx > dev_start_idx) addr_start_idx = 0; if (dev_idx++ < dev_start_idx) continue; addr_idx = 0; for_each_set_bit(addr, pnd->addrs, 64) { if (addr_idx++ < addr_start_idx) continue; if (fill_addr(skb, pnd->netdev, addr << 2, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, RTM_NEWADDR) < 0) goto out; } } out: rcu_read_unlock(); cb->args[0] = dev_idx; cb->args[1] = addr_idx; return skb->len; } /* Routes handling */ static int fill_route(struct sk_buff *skb, struct net_device *dev, u8 dst, u32 portid, u32 seq, int event) { struct rtmsg *rtm; struct nlmsghdr *nlh; nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), 0); if (nlh == NULL) return -EMSGSIZE; rtm = nlmsg_data(nlh); rtm->rtm_family = AF_PHONET; rtm->rtm_dst_len = 6; rtm->rtm_src_len = 0; rtm->rtm_tos = 0; rtm->rtm_table = RT_TABLE_MAIN; rtm->rtm_protocol = RTPROT_STATIC; rtm->rtm_scope = RT_SCOPE_UNIVERSE; rtm->rtm_type = RTN_UNICAST; rtm->rtm_flags = 0; if (nla_put_u8(skb, RTA_DST, dst) || nla_put_u32(skb, RTA_OIF, dev->ifindex)) goto nla_put_failure; nlmsg_end(skb, nlh); return 0; nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } void rtm_phonet_notify(int event, struct net_device *dev, u8 dst) { struct sk_buff *skb; int err = -ENOBUFS; skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + nla_total_size(1) + nla_total_size(4), GFP_KERNEL); if (skb == NULL) goto errout; err = fill_route(skb, dev, dst, 0, 0, event); if (err < 0) { WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; } rtnl_notify(skb, dev_net(dev), 0, RTNLGRP_PHONET_ROUTE, NULL, GFP_KERNEL); return; errout: rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_ROUTE, err); } static const struct nla_policy rtm_phonet_policy[RTA_MAX+1] = { [RTA_DST] = { .type = NLA_U8 }, [RTA_OIF] = { .type = NLA_U32 }, }; static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct nlattr *tb[RTA_MAX+1]; struct net_device *dev; struct rtmsg *rtm; int err; u8 dst; if (!netlink_capable(skb, CAP_NET_ADMIN)) return -EPERM; if (!netlink_capable(skb, CAP_SYS_ADMIN)) return -EPERM; ASSERT_RTNL(); err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_phonet_policy, extack); if (err < 0) return err; rtm = nlmsg_data(nlh); if (rtm->rtm_table != RT_TABLE_MAIN || rtm->rtm_type != RTN_UNICAST) return -EINVAL; if (tb[RTA_DST] == NULL || tb[RTA_OIF] == NULL) return -EINVAL; dst = nla_get_u8(tb[RTA_DST]); if (dst & 3) /* Phonet addresses only have 6 high-order bits */ return -EINVAL; dev = __dev_get_by_index(net, nla_get_u32(tb[RTA_OIF])); if (dev == NULL) return -ENODEV; if (nlh->nlmsg_type == RTM_NEWROUTE) err = phonet_route_add(dev, dst); else err = phonet_route_del(dev, dst); if (!err) rtm_phonet_notify(nlh->nlmsg_type, dev, dst); return err; } static int route_dumpit(struct sk_buff *skb, struct netlink_callback *cb) { struct net *net = sock_net(skb->sk); u8 addr; rcu_read_lock(); for (addr = cb->args[0]; addr < 64; addr++) { struct net_device *dev = phonet_route_get_rcu(net, addr << 2); if (!dev) continue; if (fill_route(skb, dev, addr << 2, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, RTM_NEWROUTE) < 0) goto out; } out: rcu_read_unlock(); cb->args[0] = addr; return skb->len; } int __init phonet_netlink_register(void) { int err = rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_NEWADDR, addr_doit, NULL, 0); if (err) return err; /* Further rtnl_register_module() cannot fail */ rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_DELADDR, addr_doit, NULL, 0); rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_GETADDR, NULL, getaddr_dumpit, 0); rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_NEWROUTE, route_doit, NULL, 0); rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_DELROUTE, route_doit, NULL, 0); rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_GETROUTE, NULL, route_dumpit, 0); return 0; }
linux-master
net/phonet/pn_netlink.c
// SPDX-License-Identifier: GPL-2.0-only /* * File: datagram.c * * Datagram (ISI) Phonet sockets * * Copyright (C) 2008 Nokia Corporation. * * Authors: Sakari Ailus <[email protected]> * Rémi Denis-Courmont */ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/socket.h> #include <asm/ioctls.h> #include <net/sock.h> #include <linux/phonet.h> #include <linux/export.h> #include <net/phonet/phonet.h> static int pn_backlog_rcv(struct sock *sk, struct sk_buff *skb); /* associated socket ceases to exist */ static void pn_sock_close(struct sock *sk, long timeout) { sk_common_release(sk); } static int pn_ioctl(struct sock *sk, int cmd, int *karg) { struct sk_buff *skb; switch (cmd) { case SIOCINQ: lock_sock(sk); skb = skb_peek(&sk->sk_receive_queue); *karg = skb ? skb->len : 0; release_sock(sk); return 0; case SIOCPNADDRESOURCE: case SIOCPNDELRESOURCE: { u32 res = *karg; if (res >= 256) return -EINVAL; if (cmd == SIOCPNADDRESOURCE) return pn_sock_bind_res(sk, res); else return pn_sock_unbind_res(sk, res); } } return -ENOIOCTLCMD; } /* Destroy socket. All references are gone. */ static void pn_destruct(struct sock *sk) { skb_queue_purge(&sk->sk_receive_queue); } static int pn_init(struct sock *sk) { sk->sk_destruct = pn_destruct; return 0; } static int pn_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) { DECLARE_SOCKADDR(struct sockaddr_pn *, target, msg->msg_name); struct sk_buff *skb; int err; if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL| MSG_CMSG_COMPAT)) return -EOPNOTSUPP; if (target == NULL) return -EDESTADDRREQ; if (msg->msg_namelen < sizeof(struct sockaddr_pn)) return -EINVAL; if (target->spn_family != AF_PHONET) return -EAFNOSUPPORT; skb = sock_alloc_send_skb(sk, MAX_PHONET_HEADER + len, msg->msg_flags & MSG_DONTWAIT, &err); if (skb == NULL) return err; skb_reserve(skb, MAX_PHONET_HEADER); err = memcpy_from_msg((void *)skb_put(skb, len), msg, len); if (err < 0) { kfree_skb(skb); return err; } /* * Fill in the Phonet header and * finally pass the packet forwards. */ err = pn_skb_send(sk, skb, target); /* If ok, return len. */ return (err >= 0) ? len : err; } static int pn_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { struct sk_buff *skb = NULL; struct sockaddr_pn sa; int rval = -EOPNOTSUPP; int copylen; if (flags & ~(MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_NOSIGNAL| MSG_CMSG_COMPAT)) goto out_nofree; skb = skb_recv_datagram(sk, flags, &rval); if (skb == NULL) goto out_nofree; pn_skb_get_src_sockaddr(skb, &sa); copylen = skb->len; if (len < copylen) { msg->msg_flags |= MSG_TRUNC; copylen = len; } rval = skb_copy_datagram_msg(skb, 0, msg, copylen); if (rval) { rval = -EFAULT; goto out; } rval = (flags & MSG_TRUNC) ? skb->len : copylen; if (msg->msg_name != NULL) { __sockaddr_check_size(sizeof(sa)); memcpy(msg->msg_name, &sa, sizeof(sa)); *addr_len = sizeof(sa); } out: skb_free_datagram(sk, skb); out_nofree: return rval; } /* Queue an skb for a sock. */ static int pn_backlog_rcv(struct sock *sk, struct sk_buff *skb) { int err = sock_queue_rcv_skb(sk, skb); if (err < 0) kfree_skb(skb); return err ? NET_RX_DROP : NET_RX_SUCCESS; } /* Module registration */ static struct proto pn_proto = { .close = pn_sock_close, .ioctl = pn_ioctl, .init = pn_init, .sendmsg = pn_sendmsg, .recvmsg = pn_recvmsg, .backlog_rcv = pn_backlog_rcv, .hash = pn_sock_hash, .unhash = pn_sock_unhash, .get_port = pn_sock_get_port, .obj_size = sizeof(struct pn_sock), .owner = THIS_MODULE, .name = "PHONET", }; static const struct phonet_protocol pn_dgram_proto = { .ops = &phonet_dgram_ops, .prot = &pn_proto, .sock_type = SOCK_DGRAM, }; int __init isi_register(void) { return phonet_proto_register(PN_PROTO_PHONET, &pn_dgram_proto); } void __exit isi_unregister(void) { phonet_proto_unregister(PN_PROTO_PHONET, &pn_dgram_proto); }
linux-master
net/phonet/datagram.c
// SPDX-License-Identifier: GPL-2.0-only /* * File: pep.c * * Phonet pipe protocol end point socket * * Copyright (C) 2008 Nokia Corporation. * * Author: Rémi Denis-Courmont */ #include <linux/kernel.h> #include <linux/sched/signal.h> #include <linux/slab.h> #include <linux/socket.h> #include <net/sock.h> #include <net/tcp_states.h> #include <asm/ioctls.h> #include <linux/phonet.h> #include <linux/module.h> #include <net/phonet/phonet.h> #include <net/phonet/pep.h> #include <net/phonet/gprs.h> /* sk_state values: * TCP_CLOSE sock not in use yet * TCP_CLOSE_WAIT disconnected pipe * TCP_LISTEN listening pipe endpoint * TCP_SYN_RECV connected pipe in disabled state * TCP_ESTABLISHED connected pipe in enabled state * * pep_sock locking: * - sk_state, hlist: sock lock needed * - listener: read only * - pipe_handle: read only */ #define CREDITS_MAX 10 #define CREDITS_THR 7 #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */ /* Get the next TLV sub-block. */ static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen, void *buf) { void *data = NULL; struct { u8 sb_type; u8 sb_len; } *ph, h; int buflen = *plen; ph = skb_header_pointer(skb, 0, 2, &h); if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len)) return NULL; ph->sb_len -= 2; *ptype = ph->sb_type; *plen = ph->sb_len; if (buflen > ph->sb_len) buflen = ph->sb_len; data = skb_header_pointer(skb, 2, buflen, buf); __skb_pull(skb, 2 + ph->sb_len); return data; } static struct sk_buff *pep_alloc_skb(struct sock *sk, const void *payload, int len, gfp_t priority) { struct sk_buff *skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority); if (!skb) return NULL; skb_set_owner_w(skb, sk); skb_reserve(skb, MAX_PNPIPE_HEADER); __skb_put(skb, len); skb_copy_to_linear_data(skb, payload, len); __skb_push(skb, sizeof(struct pnpipehdr)); skb_reset_transport_header(skb); return skb; } static int pep_reply(struct sock *sk, struct sk_buff *oskb, u8 code, const void *data, int len, gfp_t priority) { const struct pnpipehdr *oph = pnp_hdr(oskb); struct pnpipehdr *ph; struct sk_buff *skb; struct sockaddr_pn peer; skb = pep_alloc_skb(sk, data, len, priority); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); ph->utid = oph->utid; ph->message_id = oph->message_id + 1; /* REQ -> RESP */ ph->pipe_handle = oph->pipe_handle; ph->error_code = code; pn_skb_get_src_sockaddr(oskb, &peer); return pn_skb_send(sk, skb, &peer); } static int pep_indicate(struct sock *sk, u8 id, u8 code, const void *data, int len, gfp_t priority) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *ph; struct sk_buff *skb; skb = pep_alloc_skb(sk, data, len, priority); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); ph->utid = 0; ph->message_id = id; ph->pipe_handle = pn->pipe_handle; ph->error_code = code; return pn_skb_send(sk, skb, NULL); } #define PAD 0x00 static int pipe_handler_request(struct sock *sk, u8 id, u8 code, const void *data, int len) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *ph; struct sk_buff *skb; skb = pep_alloc_skb(sk, data, len, GFP_KERNEL); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); ph->utid = id; /* whatever */ ph->message_id = id; ph->pipe_handle = pn->pipe_handle; ph->error_code = code; return pn_skb_send(sk, skb, NULL); } static int pipe_handler_send_created_ind(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); u8 data[4] = { PN_PIPE_SB_NEGOTIATED_FC, pep_sb_size(2), pn->tx_fc, pn->rx_fc, }; return pep_indicate(sk, PNS_PIPE_CREATED_IND, 1 /* sub-blocks */, data, 4, GFP_ATOMIC); } static int pep_accept_conn(struct sock *sk, struct sk_buff *skb) { static const u8 data[20] = { PAD, PAD, PAD, 2 /* sub-blocks */, PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD, PN_MULTI_CREDIT_FLOW_CONTROL, PN_ONE_CREDIT_FLOW_CONTROL, PN_LEGACY_FLOW_CONTROL, PAD, PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD, PN_MULTI_CREDIT_FLOW_CONTROL, PN_ONE_CREDIT_FLOW_CONTROL, PN_LEGACY_FLOW_CONTROL, PAD, }; might_sleep(); return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data), GFP_KERNEL); } static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code, gfp_t priority) { static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ }; WARN_ON(code == PN_PIPE_NO_ERROR); return pep_reply(sk, skb, code, data, sizeof(data), priority); } /* Control requests are not sent by the pipe service and have a specific * message format. */ static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code, gfp_t priority) { const struct pnpipehdr *oph = pnp_hdr(oskb); struct sk_buff *skb; struct pnpipehdr *ph; struct sockaddr_pn dst; u8 data[4] = { oph->pep_type, /* PEP type */ code, /* error code, at an unusual offset */ PAD, PAD, }; skb = pep_alloc_skb(sk, data, 4, priority); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); ph->utid = oph->utid; ph->message_id = PNS_PEP_CTRL_RESP; ph->pipe_handle = oph->pipe_handle; ph->data0 = oph->data[0]; /* CTRL id */ pn_skb_get_src_sockaddr(oskb, &dst); return pn_skb_send(sk, skb, &dst); } static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority) { u8 data[4] = { type, PAD, PAD, status }; return pep_indicate(sk, PNS_PEP_STATUS_IND, PN_PEP_TYPE_COMMON, data, 4, priority); } /* Send our RX flow control information to the sender. * Socket must be locked. */ static void pipe_grant_credits(struct sock *sk, gfp_t priority) { struct pep_sock *pn = pep_sk(sk); BUG_ON(sk->sk_state != TCP_ESTABLISHED); switch (pn->rx_fc) { case PN_LEGACY_FLOW_CONTROL: /* TODO */ break; case PN_ONE_CREDIT_FLOW_CONTROL: if (pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL, PEP_IND_READY, priority) == 0) pn->rx_credits = 1; break; case PN_MULTI_CREDIT_FLOW_CONTROL: if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX) break; if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS, CREDITS_MAX - pn->rx_credits, priority) == 0) pn->rx_credits = CREDITS_MAX; break; } } static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *hdr; int wake = 0; if (!pskb_may_pull(skb, sizeof(*hdr) + 4)) return -EINVAL; hdr = pnp_hdr(skb); if (hdr->pep_type != PN_PEP_TYPE_COMMON) { net_dbg_ratelimited("Phonet unknown PEP type: %u\n", (unsigned int)hdr->pep_type); return -EOPNOTSUPP; } switch (hdr->data[0]) { case PN_PEP_IND_FLOW_CONTROL: switch (pn->tx_fc) { case PN_LEGACY_FLOW_CONTROL: switch (hdr->data[3]) { case PEP_IND_BUSY: atomic_set(&pn->tx_credits, 0); break; case PEP_IND_READY: atomic_set(&pn->tx_credits, wake = 1); break; } break; case PN_ONE_CREDIT_FLOW_CONTROL: if (hdr->data[3] == PEP_IND_READY) atomic_set(&pn->tx_credits, wake = 1); break; } break; case PN_PEP_IND_ID_MCFC_GRANT_CREDITS: if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL) break; atomic_add(wake = hdr->data[3], &pn->tx_credits); break; default: net_dbg_ratelimited("Phonet unknown PEP indication: %u\n", (unsigned int)hdr->data[0]); return -EOPNOTSUPP; } if (wake) sk->sk_write_space(sk); return 0; } static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *hdr = pnp_hdr(skb); u8 n_sb = hdr->data0; pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL; __skb_pull(skb, sizeof(*hdr)); while (n_sb > 0) { u8 type, buf[2], len = sizeof(buf); u8 *data = pep_get_sb(skb, &type, &len, buf); if (data == NULL) return -EINVAL; switch (type) { case PN_PIPE_SB_NEGOTIATED_FC: if (len < 2 || (data[0] | data[1]) > 3) break; pn->tx_fc = data[0] & 3; pn->rx_fc = data[1] & 3; break; } n_sb--; } return 0; } /* Queue an skb to a connected sock. * Socket lock must be held. */ static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *hdr = pnp_hdr(skb); struct sk_buff_head *queue; int err = 0; BUG_ON(sk->sk_state == TCP_CLOSE_WAIT); switch (hdr->message_id) { case PNS_PEP_CONNECT_REQ: pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_ATOMIC); break; case PNS_PEP_DISCONNECT_REQ: pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); sk->sk_state = TCP_CLOSE_WAIT; if (!sock_flag(sk, SOCK_DEAD)) sk->sk_state_change(sk); break; case PNS_PEP_ENABLE_REQ: /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */ pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); break; case PNS_PEP_RESET_REQ: switch (hdr->state_after_reset) { case PN_PIPE_DISABLE: pn->init_enable = 0; break; case PN_PIPE_ENABLE: pn->init_enable = 1; break; default: /* not allowed to send an error here!? */ err = -EINVAL; goto out; } fallthrough; case PNS_PEP_DISABLE_REQ: atomic_set(&pn->tx_credits, 0); pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); break; case PNS_PEP_CTRL_REQ: if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) { atomic_inc(&sk->sk_drops); break; } __skb_pull(skb, 4); queue = &pn->ctrlreq_queue; goto queue; case PNS_PIPE_ALIGNED_DATA: __skb_pull(skb, 1); fallthrough; case PNS_PIPE_DATA: __skb_pull(skb, 3); /* Pipe data header */ if (!pn_flow_safe(pn->rx_fc)) { err = sock_queue_rcv_skb(sk, skb); if (!err) return NET_RX_SUCCESS; err = -ENOBUFS; break; } if (pn->rx_credits == 0) { atomic_inc(&sk->sk_drops); err = -ENOBUFS; break; } pn->rx_credits--; queue = &sk->sk_receive_queue; goto queue; case PNS_PEP_STATUS_IND: pipe_rcv_status(sk, skb); break; case PNS_PIPE_REDIRECTED_IND: err = pipe_rcv_created(sk, skb); break; case PNS_PIPE_CREATED_IND: err = pipe_rcv_created(sk, skb); if (err) break; fallthrough; case PNS_PIPE_RESET_IND: if (!pn->init_enable) break; fallthrough; case PNS_PIPE_ENABLED_IND: if (!pn_flow_safe(pn->tx_fc)) { atomic_set(&pn->tx_credits, 1); sk->sk_write_space(sk); } if (sk->sk_state == TCP_ESTABLISHED) break; /* Nothing to do */ sk->sk_state = TCP_ESTABLISHED; pipe_grant_credits(sk, GFP_ATOMIC); break; case PNS_PIPE_DISABLED_IND: sk->sk_state = TCP_SYN_RECV; pn->rx_credits = 0; break; default: net_dbg_ratelimited("Phonet unknown PEP message: %u\n", hdr->message_id); err = -EINVAL; } out: kfree_skb(skb); return (err == -ENOBUFS) ? NET_RX_DROP : NET_RX_SUCCESS; queue: skb->dev = NULL; skb_set_owner_r(skb, sk); skb_queue_tail(queue, skb); if (!sock_flag(sk, SOCK_DEAD)) sk->sk_data_ready(sk); return NET_RX_SUCCESS; } /* Destroy connected sock. */ static void pipe_destruct(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); skb_queue_purge(&sk->sk_receive_queue); skb_queue_purge(&pn->ctrlreq_queue); } static u8 pipe_negotiate_fc(const u8 *fcs, unsigned int n) { unsigned int i; u8 final_fc = PN_NO_FLOW_CONTROL; for (i = 0; i < n; i++) { u8 fc = fcs[i]; if (fc > final_fc && fc < PN_MAX_FLOW_CONTROL) final_fc = fc; } return final_fc; } static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *hdr; u8 n_sb; if (!pskb_pull(skb, sizeof(*hdr) + 4)) return -EINVAL; hdr = pnp_hdr(skb); if (hdr->error_code != PN_PIPE_NO_ERROR) return -ECONNREFUSED; /* Parse sub-blocks */ n_sb = hdr->data[3]; while (n_sb > 0) { u8 type, buf[6], len = sizeof(buf); const u8 *data = pep_get_sb(skb, &type, &len, buf); if (data == NULL) return -EINVAL; switch (type) { case PN_PIPE_SB_REQUIRED_FC_TX: if (len < 2 || len < data[0]) break; pn->tx_fc = pipe_negotiate_fc(data + 2, len - 2); break; case PN_PIPE_SB_PREFERRED_FC_RX: if (len < 2 || len < data[0]) break; pn->rx_fc = pipe_negotiate_fc(data + 2, len - 2); break; } n_sb--; } return pipe_handler_send_created_ind(sk); } static int pep_enableresp_rcv(struct sock *sk, struct sk_buff *skb) { struct pnpipehdr *hdr = pnp_hdr(skb); if (hdr->error_code != PN_PIPE_NO_ERROR) return -ECONNREFUSED; return pep_indicate(sk, PNS_PIPE_ENABLED_IND, 0 /* sub-blocks */, NULL, 0, GFP_ATOMIC); } static void pipe_start_flow_control(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); if (!pn_flow_safe(pn->tx_fc)) { atomic_set(&pn->tx_credits, 1); sk->sk_write_space(sk); } pipe_grant_credits(sk, GFP_ATOMIC); } /* Queue an skb to an actively connected sock. * Socket lock must be held. */ static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *hdr = pnp_hdr(skb); int err = NET_RX_SUCCESS; switch (hdr->message_id) { case PNS_PIPE_ALIGNED_DATA: __skb_pull(skb, 1); fallthrough; case PNS_PIPE_DATA: __skb_pull(skb, 3); /* Pipe data header */ if (!pn_flow_safe(pn->rx_fc)) { err = sock_queue_rcv_skb(sk, skb); if (!err) return NET_RX_SUCCESS; err = NET_RX_DROP; break; } if (pn->rx_credits == 0) { atomic_inc(&sk->sk_drops); err = NET_RX_DROP; break; } pn->rx_credits--; skb->dev = NULL; skb_set_owner_r(skb, sk); skb_queue_tail(&sk->sk_receive_queue, skb); if (!sock_flag(sk, SOCK_DEAD)) sk->sk_data_ready(sk); return NET_RX_SUCCESS; case PNS_PEP_CONNECT_RESP: if (sk->sk_state != TCP_SYN_SENT) break; if (!sock_flag(sk, SOCK_DEAD)) sk->sk_state_change(sk); if (pep_connresp_rcv(sk, skb)) { sk->sk_state = TCP_CLOSE_WAIT; break; } if (pn->init_enable == PN_PIPE_DISABLE) sk->sk_state = TCP_SYN_RECV; else { sk->sk_state = TCP_ESTABLISHED; pipe_start_flow_control(sk); } break; case PNS_PEP_ENABLE_RESP: if (sk->sk_state != TCP_SYN_SENT) break; if (pep_enableresp_rcv(sk, skb)) { sk->sk_state = TCP_CLOSE_WAIT; break; } sk->sk_state = TCP_ESTABLISHED; pipe_start_flow_control(sk); break; case PNS_PEP_DISCONNECT_RESP: /* sock should already be dead, nothing to do */ break; case PNS_PEP_STATUS_IND: pipe_rcv_status(sk, skb); break; } kfree_skb(skb); return err; } /* Listening sock must be locked */ static struct sock *pep_find_pipe(const struct hlist_head *hlist, const struct sockaddr_pn *dst, u8 pipe_handle) { struct sock *sknode; u16 dobj = pn_sockaddr_get_object(dst); sk_for_each(sknode, hlist) { struct pep_sock *pnnode = pep_sk(sknode); /* Ports match, but addresses might not: */ if (pnnode->pn_sk.sobject != dobj) continue; if (pnnode->pipe_handle != pipe_handle) continue; if (sknode->sk_state == TCP_CLOSE_WAIT) continue; sock_hold(sknode); return sknode; } return NULL; } /* * Deliver an skb to a listening sock. * Socket lock must be held. * We then queue the skb to the right connected sock (if any). */ static int pep_do_rcv(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct sock *sknode; struct pnpipehdr *hdr; struct sockaddr_pn dst; u8 pipe_handle; if (!pskb_may_pull(skb, sizeof(*hdr))) goto drop; hdr = pnp_hdr(skb); pipe_handle = hdr->pipe_handle; if (pipe_handle == PN_PIPE_INVALID_HANDLE) goto drop; pn_skb_get_dst_sockaddr(skb, &dst); /* Look for an existing pipe handle */ sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle); if (sknode) return sk_receive_skb(sknode, skb, 1); switch (hdr->message_id) { case PNS_PEP_CONNECT_REQ: if (sk->sk_state != TCP_LISTEN || sk_acceptq_is_full(sk)) { pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_ATOMIC); break; } skb_queue_head(&sk->sk_receive_queue, skb); sk_acceptq_added(sk); if (!sock_flag(sk, SOCK_DEAD)) sk->sk_data_ready(sk); return NET_RX_SUCCESS; case PNS_PEP_DISCONNECT_REQ: pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); break; case PNS_PEP_CTRL_REQ: pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC); break; case PNS_PEP_RESET_REQ: case PNS_PEP_ENABLE_REQ: case PNS_PEP_DISABLE_REQ: /* invalid handle is not even allowed here! */ break; default: if ((1 << sk->sk_state) & ~(TCPF_CLOSE|TCPF_LISTEN|TCPF_CLOSE_WAIT)) /* actively connected socket */ return pipe_handler_do_rcv(sk, skb); } drop: kfree_skb(skb); return NET_RX_SUCCESS; } static int pipe_do_remove(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *ph; struct sk_buff *skb; skb = pep_alloc_skb(sk, NULL, 0, GFP_KERNEL); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); ph->utid = 0; ph->message_id = PNS_PIPE_REMOVE_REQ; ph->pipe_handle = pn->pipe_handle; ph->data0 = PAD; return pn_skb_send(sk, skb, NULL); } /* associated socket ceases to exist */ static void pep_sock_close(struct sock *sk, long timeout) { struct pep_sock *pn = pep_sk(sk); int ifindex = 0; sock_hold(sk); /* keep a reference after sk_common_release() */ sk_common_release(sk); lock_sock(sk); if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) { if (sk->sk_backlog_rcv == pipe_do_rcv) /* Forcefully remove dangling Phonet pipe */ pipe_do_remove(sk); else pipe_handler_request(sk, PNS_PEP_DISCONNECT_REQ, PAD, NULL, 0); } sk->sk_state = TCP_CLOSE; ifindex = pn->ifindex; pn->ifindex = 0; release_sock(sk); if (ifindex) gprs_detach(sk); sock_put(sk); } static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp, bool kern) { struct pep_sock *pn = pep_sk(sk), *newpn; struct sock *newsk = NULL; struct sk_buff *skb; struct pnpipehdr *hdr; struct sockaddr_pn dst, src; int err; u16 peer_type; u8 pipe_handle, enabled, n_sb; u8 aligned = 0; skb = skb_recv_datagram(sk, (flags & O_NONBLOCK) ? MSG_DONTWAIT : 0, errp); if (!skb) return NULL; lock_sock(sk); if (sk->sk_state != TCP_LISTEN) { err = -EINVAL; goto drop; } sk_acceptq_removed(sk); err = -EPROTO; if (!pskb_may_pull(skb, sizeof(*hdr) + 4)) goto drop; hdr = pnp_hdr(skb); pipe_handle = hdr->pipe_handle; switch (hdr->state_after_connect) { case PN_PIPE_DISABLE: enabled = 0; break; case PN_PIPE_ENABLE: enabled = 1; break; default: pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM, GFP_KERNEL); goto drop; } peer_type = hdr->other_pep_type << 8; /* Parse sub-blocks (options) */ n_sb = hdr->data[3]; while (n_sb > 0) { u8 type, buf[1], len = sizeof(buf); const u8 *data = pep_get_sb(skb, &type, &len, buf); if (data == NULL) goto drop; switch (type) { case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE: if (len < 1) goto drop; peer_type = (peer_type & 0xff00) | data[0]; break; case PN_PIPE_SB_ALIGNED_DATA: aligned = data[0] != 0; break; } n_sb--; } /* Check for duplicate pipe handle */ newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle); if (unlikely(newsk)) { __sock_put(newsk); newsk = NULL; pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_KERNEL); goto drop; } /* Create a new to-be-accepted sock */ newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_KERNEL, sk->sk_prot, kern); if (!newsk) { pep_reject_conn(sk, skb, PN_PIPE_ERR_OVERLOAD, GFP_KERNEL); err = -ENOBUFS; goto drop; } sock_init_data(NULL, newsk); newsk->sk_state = TCP_SYN_RECV; newsk->sk_backlog_rcv = pipe_do_rcv; newsk->sk_protocol = sk->sk_protocol; newsk->sk_destruct = pipe_destruct; newpn = pep_sk(newsk); pn_skb_get_dst_sockaddr(skb, &dst); pn_skb_get_src_sockaddr(skb, &src); newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst); newpn->pn_sk.dobject = pn_sockaddr_get_object(&src); newpn->pn_sk.resource = pn_sockaddr_get_resource(&dst); sock_hold(sk); newpn->listener = sk; skb_queue_head_init(&newpn->ctrlreq_queue); newpn->pipe_handle = pipe_handle; atomic_set(&newpn->tx_credits, 0); newpn->ifindex = 0; newpn->peer_type = peer_type; newpn->rx_credits = 0; newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL; newpn->init_enable = enabled; newpn->aligned = aligned; err = pep_accept_conn(newsk, skb); if (err) { __sock_put(sk); sock_put(newsk); newsk = NULL; goto drop; } sk_add_node(newsk, &pn->hlist); drop: release_sock(sk); kfree_skb(skb); *errp = err; return newsk; } static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len) { struct pep_sock *pn = pep_sk(sk); int err; u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD }; if (pn->pipe_handle == PN_PIPE_INVALID_HANDLE) pn->pipe_handle = 1; /* anything but INVALID_HANDLE */ err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ, pn->init_enable, data, 4); if (err) { pn->pipe_handle = PN_PIPE_INVALID_HANDLE; return err; } sk->sk_state = TCP_SYN_SENT; return 0; } static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len) { int err; err = pipe_handler_request(sk, PNS_PEP_ENABLE_REQ, PAD, NULL, 0); if (err) return err; sk->sk_state = TCP_SYN_SENT; return 0; } static int pep_ioctl(struct sock *sk, int cmd, int *karg) { struct pep_sock *pn = pep_sk(sk); int ret = -ENOIOCTLCMD; switch (cmd) { case SIOCINQ: if (sk->sk_state == TCP_LISTEN) { ret = -EINVAL; break; } lock_sock(sk); if (sock_flag(sk, SOCK_URGINLINE) && !skb_queue_empty(&pn->ctrlreq_queue)) *karg = skb_peek(&pn->ctrlreq_queue)->len; else if (!skb_queue_empty(&sk->sk_receive_queue)) *karg = skb_peek(&sk->sk_receive_queue)->len; else *karg = 0; release_sock(sk); ret = 0; break; case SIOCPNENABLEPIPE: lock_sock(sk); if (sk->sk_state == TCP_SYN_SENT) ret = -EBUSY; else if (sk->sk_state == TCP_ESTABLISHED) ret = -EISCONN; else if (!pn->pn_sk.sobject) ret = -EADDRNOTAVAIL; else ret = pep_sock_enable(sk, NULL, 0); release_sock(sk); break; } return ret; } static int pep_init(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); sk->sk_destruct = pipe_destruct; INIT_HLIST_HEAD(&pn->hlist); pn->listener = NULL; skb_queue_head_init(&pn->ctrlreq_queue); atomic_set(&pn->tx_credits, 0); pn->ifindex = 0; pn->peer_type = 0; pn->pipe_handle = PN_PIPE_INVALID_HANDLE; pn->rx_credits = 0; pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL; pn->init_enable = 1; pn->aligned = 0; return 0; } static int pep_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { struct pep_sock *pn = pep_sk(sk); int val = 0, err = 0; if (level != SOL_PNPIPE) return -ENOPROTOOPT; if (optlen >= sizeof(int)) { if (copy_from_sockptr(&val, optval, sizeof(int))) return -EFAULT; } lock_sock(sk); switch (optname) { case PNPIPE_ENCAP: if (val && val != PNPIPE_ENCAP_IP) { err = -EINVAL; break; } if (!pn->ifindex == !val) break; /* Nothing to do! */ if (!capable(CAP_NET_ADMIN)) { err = -EPERM; break; } if (val) { release_sock(sk); err = gprs_attach(sk); if (err > 0) { pn->ifindex = err; err = 0; } } else { pn->ifindex = 0; release_sock(sk); gprs_detach(sk); err = 0; } goto out_norel; case PNPIPE_HANDLE: if ((sk->sk_state == TCP_CLOSE) && (val >= 0) && (val < PN_PIPE_INVALID_HANDLE)) pn->pipe_handle = val; else err = -EINVAL; break; case PNPIPE_INITSTATE: pn->init_enable = !!val; break; default: err = -ENOPROTOOPT; } release_sock(sk); out_norel: return err; } static int pep_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { struct pep_sock *pn = pep_sk(sk); int len, val; if (level != SOL_PNPIPE) return -ENOPROTOOPT; if (get_user(len, optlen)) return -EFAULT; switch (optname) { case PNPIPE_ENCAP: val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE; break; case PNPIPE_IFINDEX: val = pn->ifindex; break; case PNPIPE_HANDLE: val = pn->pipe_handle; if (val == PN_PIPE_INVALID_HANDLE) return -EINVAL; break; case PNPIPE_INITSTATE: val = pn->init_enable; break; default: return -ENOPROTOOPT; } len = min_t(unsigned int, sizeof(int), len); if (put_user(len, optlen)) return -EFAULT; if (put_user(val, (int __user *) optval)) return -EFAULT; return 0; } static int pipe_skb_send(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *ph; int err; if (pn_flow_safe(pn->tx_fc) && !atomic_add_unless(&pn->tx_credits, -1, 0)) { kfree_skb(skb); return -ENOBUFS; } skb_push(skb, 3 + pn->aligned); skb_reset_transport_header(skb); ph = pnp_hdr(skb); ph->utid = 0; if (pn->aligned) { ph->message_id = PNS_PIPE_ALIGNED_DATA; ph->data0 = 0; /* padding */ } else ph->message_id = PNS_PIPE_DATA; ph->pipe_handle = pn->pipe_handle; err = pn_skb_send(sk, skb, NULL); if (err && pn_flow_safe(pn->tx_fc)) atomic_inc(&pn->tx_credits); return err; } static int pep_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) { struct pep_sock *pn = pep_sk(sk); struct sk_buff *skb; long timeo; int flags = msg->msg_flags; int err, done; if (len > USHRT_MAX) return -EMSGSIZE; if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL| MSG_CMSG_COMPAT)) || !(msg->msg_flags & MSG_EOR)) return -EOPNOTSUPP; skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len, flags & MSG_DONTWAIT, &err); if (!skb) return err; skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned); err = memcpy_from_msg(skb_put(skb, len), msg, len); if (err < 0) goto outfree; lock_sock(sk); timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) { err = -ENOTCONN; goto out; } if (sk->sk_state != TCP_ESTABLISHED) { /* Wait until the pipe gets to enabled state */ disabled: err = sk_stream_wait_connect(sk, &timeo); if (err) goto out; if (sk->sk_state == TCP_CLOSE_WAIT) { err = -ECONNRESET; goto out; } } BUG_ON(sk->sk_state != TCP_ESTABLISHED); /* Wait until flow control allows TX */ done = atomic_read(&pn->tx_credits); while (!done) { DEFINE_WAIT_FUNC(wait, woken_wake_function); if (!timeo) { err = -EAGAIN; goto out; } if (signal_pending(current)) { err = sock_intr_errno(timeo); goto out; } add_wait_queue(sk_sleep(sk), &wait); done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits), &wait); remove_wait_queue(sk_sleep(sk), &wait); if (sk->sk_state != TCP_ESTABLISHED) goto disabled; } err = pipe_skb_send(sk, skb); if (err >= 0) err = len; /* success! */ skb = NULL; out: release_sock(sk); outfree: kfree_skb(skb); return err; } int pep_writeable(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); return atomic_read(&pn->tx_credits); } int pep_write(struct sock *sk, struct sk_buff *skb) { struct sk_buff *rskb, *fs; int flen = 0; if (pep_sk(sk)->aligned) return pipe_skb_send(sk, skb); rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC); if (!rskb) { kfree_skb(skb); return -ENOMEM; } skb_shinfo(rskb)->frag_list = skb; rskb->len += skb->len; rskb->data_len += rskb->len; rskb->truesize += rskb->len; /* Avoid nested fragments */ skb_walk_frags(skb, fs) flen += fs->len; skb->next = skb_shinfo(skb)->frag_list; skb_frag_list_init(skb); skb->len -= flen; skb->data_len -= flen; skb->truesize -= flen; skb_reserve(rskb, MAX_PHONET_HEADER + 3); return pipe_skb_send(sk, rskb); } struct sk_buff *pep_read(struct sock *sk) { struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue); if (sk->sk_state == TCP_ESTABLISHED) pipe_grant_credits(sk, GFP_ATOMIC); return skb; } static int pep_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { struct sk_buff *skb; int err; if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL| MSG_NOSIGNAL|MSG_CMSG_COMPAT)) return -EOPNOTSUPP; if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE))) return -ENOTCONN; if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) { /* Dequeue and acknowledge control request */ struct pep_sock *pn = pep_sk(sk); if (flags & MSG_PEEK) return -EOPNOTSUPP; skb = skb_dequeue(&pn->ctrlreq_queue); if (skb) { pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR, GFP_KERNEL); msg->msg_flags |= MSG_OOB; goto copy; } if (flags & MSG_OOB) return -EINVAL; } skb = skb_recv_datagram(sk, flags, &err); lock_sock(sk); if (skb == NULL) { if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT) err = -ECONNRESET; release_sock(sk); return err; } if (sk->sk_state == TCP_ESTABLISHED) pipe_grant_credits(sk, GFP_KERNEL); release_sock(sk); copy: msg->msg_flags |= MSG_EOR; if (skb->len > len) msg->msg_flags |= MSG_TRUNC; else len = skb->len; err = skb_copy_datagram_msg(skb, 0, msg, len); if (!err) err = (flags & MSG_TRUNC) ? skb->len : len; skb_free_datagram(sk, skb); return err; } static void pep_sock_unhash(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); struct sock *skparent = NULL; lock_sock(sk); if (pn->listener != NULL) { skparent = pn->listener; pn->listener = NULL; release_sock(sk); pn = pep_sk(skparent); lock_sock(skparent); sk_del_node_init(sk); sk = skparent; } /* Unhash a listening sock only when it is closed * and all of its active connected pipes are closed. */ if (hlist_empty(&pn->hlist)) pn_sock_unhash(&pn->pn_sk.sk); release_sock(sk); if (skparent) sock_put(skparent); } static struct proto pep_proto = { .close = pep_sock_close, .accept = pep_sock_accept, .connect = pep_sock_connect, .ioctl = pep_ioctl, .init = pep_init, .setsockopt = pep_setsockopt, .getsockopt = pep_getsockopt, .sendmsg = pep_sendmsg, .recvmsg = pep_recvmsg, .backlog_rcv = pep_do_rcv, .hash = pn_sock_hash, .unhash = pep_sock_unhash, .get_port = pn_sock_get_port, .obj_size = sizeof(struct pep_sock), .owner = THIS_MODULE, .name = "PNPIPE", }; static const struct phonet_protocol pep_pn_proto = { .ops = &phonet_stream_ops, .prot = &pep_proto, .sock_type = SOCK_SEQPACKET, }; static int __init pep_register(void) { return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto); } static void __exit pep_unregister(void) { phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto); } module_init(pep_register); module_exit(pep_unregister); MODULE_AUTHOR("Remi Denis-Courmont, Nokia"); MODULE_DESCRIPTION("Phonet pipe protocol"); MODULE_LICENSE("GPL"); MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);
linux-master
net/phonet/pep.c
// SPDX-License-Identifier: GPL-2.0-only /* * File: socket.c * * Phonet sockets * * Copyright (C) 2008 Nokia Corporation. * * Authors: Sakari Ailus <[email protected]> * Rémi Denis-Courmont */ #include <linux/gfp.h> #include <linux/kernel.h> #include <linux/net.h> #include <linux/poll.h> #include <linux/sched/signal.h> #include <net/sock.h> #include <net/tcp_states.h> #include <linux/phonet.h> #include <linux/export.h> #include <net/phonet/phonet.h> #include <net/phonet/pep.h> #include <net/phonet/pn_dev.h> static int pn_socket_release(struct socket *sock) { struct sock *sk = sock->sk; if (sk) { sock->sk = NULL; sk->sk_prot->close(sk, 0); } return 0; } #define PN_HASHSIZE 16 #define PN_HASHMASK (PN_HASHSIZE-1) static struct { struct hlist_head hlist[PN_HASHSIZE]; struct mutex lock; } pnsocks; void __init pn_sock_init(void) { unsigned int i; for (i = 0; i < PN_HASHSIZE; i++) INIT_HLIST_HEAD(pnsocks.hlist + i); mutex_init(&pnsocks.lock); } static struct hlist_head *pn_hash_list(u16 obj) { return pnsocks.hlist + (obj & PN_HASHMASK); } /* * Find address based on socket address, match only certain fields. * Also grab sock if it was found. Remember to sock_put it later. */ struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn) { struct sock *sknode; struct sock *rval = NULL; u16 obj = pn_sockaddr_get_object(spn); u8 res = spn->spn_resource; struct hlist_head *hlist = pn_hash_list(obj); rcu_read_lock(); sk_for_each_rcu(sknode, hlist) { struct pn_sock *pn = pn_sk(sknode); BUG_ON(!pn->sobject); /* unbound socket */ if (!net_eq(sock_net(sknode), net)) continue; if (pn_port(obj)) { /* Look up socket by port */ if (pn_port(pn->sobject) != pn_port(obj)) continue; } else { /* If port is zero, look up by resource */ if (pn->resource != res) continue; } if (pn_addr(pn->sobject) && pn_addr(pn->sobject) != pn_addr(obj)) continue; rval = sknode; sock_hold(sknode); break; } rcu_read_unlock(); return rval; } /* Deliver a broadcast packet (only in bottom-half) */ void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb) { struct hlist_head *hlist = pnsocks.hlist; unsigned int h; rcu_read_lock(); for (h = 0; h < PN_HASHSIZE; h++) { struct sock *sknode; sk_for_each(sknode, hlist) { struct sk_buff *clone; if (!net_eq(sock_net(sknode), net)) continue; if (!sock_flag(sknode, SOCK_BROADCAST)) continue; clone = skb_clone(skb, GFP_ATOMIC); if (clone) { sock_hold(sknode); sk_receive_skb(sknode, clone, 0); } } hlist++; } rcu_read_unlock(); } int pn_sock_hash(struct sock *sk) { struct hlist_head *hlist = pn_hash_list(pn_sk(sk)->sobject); mutex_lock(&pnsocks.lock); sk_add_node_rcu(sk, hlist); mutex_unlock(&pnsocks.lock); return 0; } EXPORT_SYMBOL(pn_sock_hash); void pn_sock_unhash(struct sock *sk) { mutex_lock(&pnsocks.lock); sk_del_node_init_rcu(sk); mutex_unlock(&pnsocks.lock); pn_sock_unbind_all_res(sk); synchronize_rcu(); } EXPORT_SYMBOL(pn_sock_unhash); static DEFINE_MUTEX(port_mutex); static int pn_socket_bind(struct socket *sock, struct sockaddr *addr, int len) { struct sock *sk = sock->sk; struct pn_sock *pn = pn_sk(sk); struct sockaddr_pn *spn = (struct sockaddr_pn *)addr; int err; u16 handle; u8 saddr; if (sk->sk_prot->bind) return sk->sk_prot->bind(sk, addr, len); if (len < sizeof(struct sockaddr_pn)) return -EINVAL; if (spn->spn_family != AF_PHONET) return -EAFNOSUPPORT; handle = pn_sockaddr_get_object((struct sockaddr_pn *)addr); saddr = pn_addr(handle); if (saddr && phonet_address_lookup(sock_net(sk), saddr)) return -EADDRNOTAVAIL; lock_sock(sk); if (sk->sk_state != TCP_CLOSE || pn_port(pn->sobject)) { err = -EINVAL; /* attempt to rebind */ goto out; } WARN_ON(sk_hashed(sk)); mutex_lock(&port_mutex); err = sk->sk_prot->get_port(sk, pn_port(handle)); if (err) goto out_port; /* get_port() sets the port, bind() sets the address if applicable */ pn->sobject = pn_object(saddr, pn_port(pn->sobject)); pn->resource = spn->spn_resource; /* Enable RX on the socket */ err = sk->sk_prot->hash(sk); out_port: mutex_unlock(&port_mutex); out: release_sock(sk); return err; } static int pn_socket_autobind(struct socket *sock) { struct sockaddr_pn sa; int err; memset(&sa, 0, sizeof(sa)); sa.spn_family = AF_PHONET; err = pn_socket_bind(sock, (struct sockaddr *)&sa, sizeof(struct sockaddr_pn)); if (err != -EINVAL) return err; BUG_ON(!pn_port(pn_sk(sock->sk)->sobject)); return 0; /* socket was already bound */ } static int pn_socket_connect(struct socket *sock, struct sockaddr *addr, int len, int flags) { struct sock *sk = sock->sk; struct pn_sock *pn = pn_sk(sk); struct sockaddr_pn *spn = (struct sockaddr_pn *)addr; struct task_struct *tsk = current; long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); int err; if (pn_socket_autobind(sock)) return -ENOBUFS; if (len < sizeof(struct sockaddr_pn)) return -EINVAL; if (spn->spn_family != AF_PHONET) return -EAFNOSUPPORT; lock_sock(sk); switch (sock->state) { case SS_UNCONNECTED: if (sk->sk_state != TCP_CLOSE) { err = -EISCONN; goto out; } break; case SS_CONNECTING: err = -EALREADY; goto out; default: err = -EISCONN; goto out; } pn->dobject = pn_sockaddr_get_object(spn); pn->resource = pn_sockaddr_get_resource(spn); sock->state = SS_CONNECTING; err = sk->sk_prot->connect(sk, addr, len); if (err) { sock->state = SS_UNCONNECTED; pn->dobject = 0; goto out; } while (sk->sk_state == TCP_SYN_SENT) { DEFINE_WAIT(wait); if (!timeo) { err = -EINPROGRESS; goto out; } if (signal_pending(tsk)) { err = sock_intr_errno(timeo); goto out; } prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); release_sock(sk); timeo = schedule_timeout(timeo); lock_sock(sk); finish_wait(sk_sleep(sk), &wait); } if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) err = 0; else if (sk->sk_state == TCP_CLOSE_WAIT) err = -ECONNRESET; else err = -ECONNREFUSED; sock->state = err ? SS_UNCONNECTED : SS_CONNECTED; out: release_sock(sk); return err; } static int pn_socket_accept(struct socket *sock, struct socket *newsock, int flags, bool kern) { struct sock *sk = sock->sk; struct sock *newsk; int err; if (unlikely(sk->sk_state != TCP_LISTEN)) return -EINVAL; newsk = sk->sk_prot->accept(sk, flags, &err, kern); if (!newsk) return err; lock_sock(newsk); sock_graft(newsk, newsock); newsock->state = SS_CONNECTED; release_sock(newsk); return 0; } static int pn_socket_getname(struct socket *sock, struct sockaddr *addr, int peer) { struct sock *sk = sock->sk; struct pn_sock *pn = pn_sk(sk); memset(addr, 0, sizeof(struct sockaddr_pn)); addr->sa_family = AF_PHONET; if (!peer) /* Race with bind() here is userland's problem. */ pn_sockaddr_set_object((struct sockaddr_pn *)addr, pn->sobject); return sizeof(struct sockaddr_pn); } static __poll_t pn_socket_poll(struct file *file, struct socket *sock, poll_table *wait) { struct sock *sk = sock->sk; struct pep_sock *pn = pep_sk(sk); __poll_t mask = 0; poll_wait(file, sk_sleep(sk), wait); if (sk->sk_state == TCP_CLOSE) return EPOLLERR; if (!skb_queue_empty_lockless(&sk->sk_receive_queue)) mask |= EPOLLIN | EPOLLRDNORM; if (!skb_queue_empty_lockless(&pn->ctrlreq_queue)) mask |= EPOLLPRI; if (!mask && sk->sk_state == TCP_CLOSE_WAIT) return EPOLLHUP; if (sk->sk_state == TCP_ESTABLISHED && refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf && atomic_read(&pn->tx_credits)) mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; return mask; } static int pn_socket_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) { struct sock *sk = sock->sk; struct pn_sock *pn = pn_sk(sk); if (cmd == SIOCPNGETOBJECT) { struct net_device *dev; u16 handle; u8 saddr; if (get_user(handle, (__u16 __user *)arg)) return -EFAULT; lock_sock(sk); if (sk->sk_bound_dev_if) dev = dev_get_by_index(sock_net(sk), sk->sk_bound_dev_if); else dev = phonet_device_get(sock_net(sk)); if (dev && (dev->flags & IFF_UP)) saddr = phonet_address_get(dev, pn_addr(handle)); else saddr = PN_NO_ADDR; release_sock(sk); dev_put(dev); if (saddr == PN_NO_ADDR) return -EHOSTUNREACH; handle = pn_object(saddr, pn_port(pn->sobject)); return put_user(handle, (__u16 __user *)arg); } return sk_ioctl(sk, cmd, (void __user *)arg); } static int pn_socket_listen(struct socket *sock, int backlog) { struct sock *sk = sock->sk; int err = 0; if (pn_socket_autobind(sock)) return -ENOBUFS; lock_sock(sk); if (sock->state != SS_UNCONNECTED) { err = -EINVAL; goto out; } if (sk->sk_state != TCP_LISTEN) { sk->sk_state = TCP_LISTEN; sk->sk_ack_backlog = 0; } sk->sk_max_ack_backlog = backlog; out: release_sock(sk); return err; } static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) { struct sock *sk = sock->sk; if (pn_socket_autobind(sock)) return -EAGAIN; return sk->sk_prot->sendmsg(sk, m, total_len); } const struct proto_ops phonet_dgram_ops = { .family = AF_PHONET, .owner = THIS_MODULE, .release = pn_socket_release, .bind = pn_socket_bind, .connect = sock_no_connect, .socketpair = sock_no_socketpair, .accept = sock_no_accept, .getname = pn_socket_getname, .poll = datagram_poll, .ioctl = pn_socket_ioctl, .listen = sock_no_listen, .shutdown = sock_no_shutdown, .sendmsg = pn_socket_sendmsg, .recvmsg = sock_common_recvmsg, .mmap = sock_no_mmap, }; const struct proto_ops phonet_stream_ops = { .family = AF_PHONET, .owner = THIS_MODULE, .release = pn_socket_release, .bind = pn_socket_bind, .connect = pn_socket_connect, .socketpair = sock_no_socketpair, .accept = pn_socket_accept, .getname = pn_socket_getname, .poll = pn_socket_poll, .ioctl = pn_socket_ioctl, .listen = pn_socket_listen, .shutdown = sock_no_shutdown, .setsockopt = sock_common_setsockopt, .getsockopt = sock_common_getsockopt, .sendmsg = pn_socket_sendmsg, .recvmsg = sock_common_recvmsg, .mmap = sock_no_mmap, }; EXPORT_SYMBOL(phonet_stream_ops); /* allocate port for a socket */ int pn_sock_get_port(struct sock *sk, unsigned short sport) { static int port_cur; struct net *net = sock_net(sk); struct pn_sock *pn = pn_sk(sk); struct sockaddr_pn try_sa; struct sock *tmpsk; memset(&try_sa, 0, sizeof(struct sockaddr_pn)); try_sa.spn_family = AF_PHONET; WARN_ON(!mutex_is_locked(&port_mutex)); if (!sport) { /* search free port */ int port, pmin, pmax; phonet_get_local_port_range(&pmin, &pmax); for (port = pmin; port <= pmax; port++) { port_cur++; if (port_cur < pmin || port_cur > pmax) port_cur = pmin; pn_sockaddr_set_port(&try_sa, port_cur); tmpsk = pn_find_sock_by_sa(net, &try_sa); if (tmpsk == NULL) { sport = port_cur; goto found; } else sock_put(tmpsk); } } else { /* try to find specific port */ pn_sockaddr_set_port(&try_sa, sport); tmpsk = pn_find_sock_by_sa(net, &try_sa); if (tmpsk == NULL) /* No sock there! We can use that port... */ goto found; else sock_put(tmpsk); } /* the port must be in use already */ return -EADDRINUSE; found: pn->sobject = pn_object(pn_addr(pn->sobject), sport); return 0; } EXPORT_SYMBOL(pn_sock_get_port); #ifdef CONFIG_PROC_FS static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos) { struct net *net = seq_file_net(seq); struct hlist_head *hlist = pnsocks.hlist; struct sock *sknode; unsigned int h; for (h = 0; h < PN_HASHSIZE; h++) { sk_for_each_rcu(sknode, hlist) { if (!net_eq(net, sock_net(sknode))) continue; if (!pos) return sknode; pos--; } hlist++; } return NULL; } static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk) { struct net *net = seq_file_net(seq); do sk = sk_next(sk); while (sk && !net_eq(net, sock_net(sk))); return sk; } static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos) __acquires(rcu) { rcu_read_lock(); return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; } static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct sock *sk; if (v == SEQ_START_TOKEN) sk = pn_sock_get_idx(seq, 0); else sk = pn_sock_get_next(seq, v); (*pos)++; return sk; } static void pn_sock_seq_stop(struct seq_file *seq, void *v) __releases(rcu) { rcu_read_unlock(); } static int pn_sock_seq_show(struct seq_file *seq, void *v) { seq_setwidth(seq, 127); if (v == SEQ_START_TOKEN) seq_puts(seq, "pt loc rem rs st tx_queue rx_queue " " uid inode ref pointer drops"); else { struct sock *sk = v; struct pn_sock *pn = pn_sk(sk); seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %lu " "%d %pK %u", sk->sk_protocol, pn->sobject, pn->dobject, pn->resource, sk->sk_state, sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk), from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), sock_i_ino(sk), refcount_read(&sk->sk_refcnt), sk, atomic_read(&sk->sk_drops)); } seq_pad(seq, '\n'); return 0; } const struct seq_operations pn_sock_seq_ops = { .start = pn_sock_seq_start, .next = pn_sock_seq_next, .stop = pn_sock_seq_stop, .show = pn_sock_seq_show, }; #endif static struct { struct sock *sk[256]; } pnres; /* * Find and hold socket based on resource. */ struct sock *pn_find_sock_by_res(struct net *net, u8 res) { struct sock *sk; if (!net_eq(net, &init_net)) return NULL; rcu_read_lock(); sk = rcu_dereference(pnres.sk[res]); if (sk) sock_hold(sk); rcu_read_unlock(); return sk; } static DEFINE_MUTEX(resource_mutex); int pn_sock_bind_res(struct sock *sk, u8 res) { int ret = -EADDRINUSE; if (!net_eq(sock_net(sk), &init_net)) return -ENOIOCTLCMD; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (pn_socket_autobind(sk->sk_socket)) return -EAGAIN; mutex_lock(&resource_mutex); if (pnres.sk[res] == NULL) { sock_hold(sk); rcu_assign_pointer(pnres.sk[res], sk); ret = 0; } mutex_unlock(&resource_mutex); return ret; } int pn_sock_unbind_res(struct sock *sk, u8 res) { int ret = -ENOENT; if (!capable(CAP_SYS_ADMIN)) return -EPERM; mutex_lock(&resource_mutex); if (pnres.sk[res] == sk) { RCU_INIT_POINTER(pnres.sk[res], NULL); ret = 0; } mutex_unlock(&resource_mutex); if (ret == 0) { synchronize_rcu(); sock_put(sk); } return ret; } void pn_sock_unbind_all_res(struct sock *sk) { unsigned int res, match = 0; mutex_lock(&resource_mutex); for (res = 0; res < 256; res++) { if (pnres.sk[res] == sk) { RCU_INIT_POINTER(pnres.sk[res], NULL); match++; } } mutex_unlock(&resource_mutex); while (match > 0) { __sock_put(sk); match--; } /* Caller is responsible for RCU sync before final sock_put() */ } #ifdef CONFIG_PROC_FS static struct sock **pn_res_get_idx(struct seq_file *seq, loff_t pos) { struct net *net = seq_file_net(seq); unsigned int i; if (!net_eq(net, &init_net)) return NULL; for (i = 0; i < 256; i++) { if (pnres.sk[i] == NULL) continue; if (!pos) return pnres.sk + i; pos--; } return NULL; } static struct sock **pn_res_get_next(struct seq_file *seq, struct sock **sk) { struct net *net = seq_file_net(seq); unsigned int i; BUG_ON(!net_eq(net, &init_net)); for (i = (sk - pnres.sk) + 1; i < 256; i++) if (pnres.sk[i]) return pnres.sk + i; return NULL; } static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos) __acquires(resource_mutex) { mutex_lock(&resource_mutex); return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; } static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct sock **sk; if (v == SEQ_START_TOKEN) sk = pn_res_get_idx(seq, 0); else sk = pn_res_get_next(seq, v); (*pos)++; return sk; } static void pn_res_seq_stop(struct seq_file *seq, void *v) __releases(resource_mutex) { mutex_unlock(&resource_mutex); } static int pn_res_seq_show(struct seq_file *seq, void *v) { seq_setwidth(seq, 63); if (v == SEQ_START_TOKEN) seq_puts(seq, "rs uid inode"); else { struct sock **psk = v; struct sock *sk = *psk; seq_printf(seq, "%02X %5u %lu", (int) (psk - pnres.sk), from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), sock_i_ino(sk)); } seq_pad(seq, '\n'); return 0; } const struct seq_operations pn_res_seq_ops = { .start = pn_res_seq_start, .next = pn_res_seq_next, .stop = pn_res_seq_stop, .show = pn_res_seq_show, }; #endif
linux-master
net/phonet/socket.c
// SPDX-License-Identifier: GPL-2.0-only /* * File: pn_dev.c * * Phonet network device * * Copyright (C) 2008 Nokia Corporation. * * Authors: Sakari Ailus <[email protected]> * Rémi Denis-Courmont */ #include <linux/kernel.h> #include <linux/net.h> #include <linux/slab.h> #include <linux/netdevice.h> #include <linux/phonet.h> #include <linux/proc_fs.h> #include <linux/if_arp.h> #include <net/sock.h> #include <net/netns/generic.h> #include <net/phonet/pn_dev.h> struct phonet_routes { struct mutex lock; struct net_device __rcu *table[64]; }; struct phonet_net { struct phonet_device_list pndevs; struct phonet_routes routes; }; static unsigned int phonet_net_id __read_mostly; static struct phonet_net *phonet_pernet(struct net *net) { return net_generic(net, phonet_net_id); } struct phonet_device_list *phonet_device_list(struct net *net) { struct phonet_net *pnn = phonet_pernet(net); return &pnn->pndevs; } /* Allocate new Phonet device. */ static struct phonet_device *__phonet_device_alloc(struct net_device *dev) { struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev)); struct phonet_device *pnd = kmalloc(sizeof(*pnd), GFP_ATOMIC); if (pnd == NULL) return NULL; pnd->netdev = dev; bitmap_zero(pnd->addrs, 64); BUG_ON(!mutex_is_locked(&pndevs->lock)); list_add_rcu(&pnd->list, &pndevs->list); return pnd; } static struct phonet_device *__phonet_get(struct net_device *dev) { struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev)); struct phonet_device *pnd; BUG_ON(!mutex_is_locked(&pndevs->lock)); list_for_each_entry(pnd, &pndevs->list, list) { if (pnd->netdev == dev) return pnd; } return NULL; } static struct phonet_device *__phonet_get_rcu(struct net_device *dev) { struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev)); struct phonet_device *pnd; list_for_each_entry_rcu(pnd, &pndevs->list, list) { if (pnd->netdev == dev) return pnd; } return NULL; } static void phonet_device_destroy(struct net_device *dev) { struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev)); struct phonet_device *pnd; ASSERT_RTNL(); mutex_lock(&pndevs->lock); pnd = __phonet_get(dev); if (pnd) list_del_rcu(&pnd->list); mutex_unlock(&pndevs->lock); if (pnd) { u8 addr; for_each_set_bit(addr, pnd->addrs, 64) phonet_address_notify(RTM_DELADDR, dev, addr); kfree(pnd); } } struct net_device *phonet_device_get(struct net *net) { struct phonet_device_list *pndevs = phonet_device_list(net); struct phonet_device *pnd; struct net_device *dev = NULL; rcu_read_lock(); list_for_each_entry_rcu(pnd, &pndevs->list, list) { dev = pnd->netdev; BUG_ON(!dev); if ((dev->reg_state == NETREG_REGISTERED) && ((pnd->netdev->flags & IFF_UP)) == IFF_UP) break; dev = NULL; } dev_hold(dev); rcu_read_unlock(); return dev; } int phonet_address_add(struct net_device *dev, u8 addr) { struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev)); struct phonet_device *pnd; int err = 0; mutex_lock(&pndevs->lock); /* Find or create Phonet-specific device data */ pnd = __phonet_get(dev); if (pnd == NULL) pnd = __phonet_device_alloc(dev); if (unlikely(pnd == NULL)) err = -ENOMEM; else if (test_and_set_bit(addr >> 2, pnd->addrs)) err = -EEXIST; mutex_unlock(&pndevs->lock); return err; } int phonet_address_del(struct net_device *dev, u8 addr) { struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev)); struct phonet_device *pnd; int err = 0; mutex_lock(&pndevs->lock); pnd = __phonet_get(dev); if (!pnd || !test_and_clear_bit(addr >> 2, pnd->addrs)) { err = -EADDRNOTAVAIL; pnd = NULL; } else if (bitmap_empty(pnd->addrs, 64)) list_del_rcu(&pnd->list); else pnd = NULL; mutex_unlock(&pndevs->lock); if (pnd) kfree_rcu(pnd, rcu); return err; } /* Gets a source address toward a destination, through a interface. */ u8 phonet_address_get(struct net_device *dev, u8 daddr) { struct phonet_device *pnd; u8 saddr; rcu_read_lock(); pnd = __phonet_get_rcu(dev); if (pnd) { BUG_ON(bitmap_empty(pnd->addrs, 64)); /* Use same source address as destination, if possible */ if (test_bit(daddr >> 2, pnd->addrs)) saddr = daddr; else saddr = find_first_bit(pnd->addrs, 64) << 2; } else saddr = PN_NO_ADDR; rcu_read_unlock(); if (saddr == PN_NO_ADDR) { /* Fallback to another device */ struct net_device *def_dev; def_dev = phonet_device_get(dev_net(dev)); if (def_dev) { if (def_dev != dev) saddr = phonet_address_get(def_dev, daddr); dev_put(def_dev); } } return saddr; } int phonet_address_lookup(struct net *net, u8 addr) { struct phonet_device_list *pndevs = phonet_device_list(net); struct phonet_device *pnd; int err = -EADDRNOTAVAIL; rcu_read_lock(); list_for_each_entry_rcu(pnd, &pndevs->list, list) { /* Don't allow unregistering devices! */ if ((pnd->netdev->reg_state != NETREG_REGISTERED) || ((pnd->netdev->flags & IFF_UP)) != IFF_UP) continue; if (test_bit(addr >> 2, pnd->addrs)) { err = 0; goto found; } } found: rcu_read_unlock(); return err; } /* automatically configure a Phonet device, if supported */ static int phonet_device_autoconf(struct net_device *dev) { struct if_phonet_req req; int ret; if (!dev->netdev_ops->ndo_siocdevprivate) return -EOPNOTSUPP; ret = dev->netdev_ops->ndo_siocdevprivate(dev, (struct ifreq *)&req, NULL, SIOCPNGAUTOCONF); if (ret < 0) return ret; ASSERT_RTNL(); ret = phonet_address_add(dev, req.ifr_phonet_autoconf.device); if (ret) return ret; phonet_address_notify(RTM_NEWADDR, dev, req.ifr_phonet_autoconf.device); return 0; } static void phonet_route_autodel(struct net_device *dev) { struct phonet_net *pnn = phonet_pernet(dev_net(dev)); unsigned int i; DECLARE_BITMAP(deleted, 64); /* Remove left-over Phonet routes */ bitmap_zero(deleted, 64); mutex_lock(&pnn->routes.lock); for (i = 0; i < 64; i++) if (rcu_access_pointer(pnn->routes.table[i]) == dev) { RCU_INIT_POINTER(pnn->routes.table[i], NULL); set_bit(i, deleted); } mutex_unlock(&pnn->routes.lock); if (bitmap_empty(deleted, 64)) return; /* short-circuit RCU */ synchronize_rcu(); for_each_set_bit(i, deleted, 64) { rtm_phonet_notify(RTM_DELROUTE, dev, i); dev_put(dev); } } /* notify Phonet of device events */ static int phonet_device_notify(struct notifier_block *me, unsigned long what, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); switch (what) { case NETDEV_REGISTER: if (dev->type == ARPHRD_PHONET) phonet_device_autoconf(dev); break; case NETDEV_UNREGISTER: phonet_device_destroy(dev); phonet_route_autodel(dev); break; } return 0; } static struct notifier_block phonet_device_notifier = { .notifier_call = phonet_device_notify, .priority = 0, }; /* Per-namespace Phonet devices handling */ static int __net_init phonet_init_net(struct net *net) { struct phonet_net *pnn = phonet_pernet(net); if (!proc_create_net("phonet", 0, net->proc_net, &pn_sock_seq_ops, sizeof(struct seq_net_private))) return -ENOMEM; INIT_LIST_HEAD(&pnn->pndevs.list); mutex_init(&pnn->pndevs.lock); mutex_init(&pnn->routes.lock); return 0; } static void __net_exit phonet_exit_net(struct net *net) { struct phonet_net *pnn = phonet_pernet(net); remove_proc_entry("phonet", net->proc_net); WARN_ON_ONCE(!list_empty(&pnn->pndevs.list)); } static struct pernet_operations phonet_net_ops = { .init = phonet_init_net, .exit = phonet_exit_net, .id = &phonet_net_id, .size = sizeof(struct phonet_net), }; /* Initialize Phonet devices list */ int __init phonet_device_init(void) { int err = register_pernet_subsys(&phonet_net_ops); if (err) return err; proc_create_net("pnresource", 0, init_net.proc_net, &pn_res_seq_ops, sizeof(struct seq_net_private)); register_netdevice_notifier(&phonet_device_notifier); err = phonet_netlink_register(); if (err) phonet_device_exit(); return err; } void phonet_device_exit(void) { rtnl_unregister_all(PF_PHONET); unregister_netdevice_notifier(&phonet_device_notifier); unregister_pernet_subsys(&phonet_net_ops); remove_proc_entry("pnresource", init_net.proc_net); } int phonet_route_add(struct net_device *dev, u8 daddr) { struct phonet_net *pnn = phonet_pernet(dev_net(dev)); struct phonet_routes *routes = &pnn->routes; int err = -EEXIST; daddr = daddr >> 2; mutex_lock(&routes->lock); if (routes->table[daddr] == NULL) { rcu_assign_pointer(routes->table[daddr], dev); dev_hold(dev); err = 0; } mutex_unlock(&routes->lock); return err; } int phonet_route_del(struct net_device *dev, u8 daddr) { struct phonet_net *pnn = phonet_pernet(dev_net(dev)); struct phonet_routes *routes = &pnn->routes; daddr = daddr >> 2; mutex_lock(&routes->lock); if (rcu_access_pointer(routes->table[daddr]) == dev) RCU_INIT_POINTER(routes->table[daddr], NULL); else dev = NULL; mutex_unlock(&routes->lock); if (!dev) return -ENOENT; synchronize_rcu(); dev_put(dev); return 0; } struct net_device *phonet_route_get_rcu(struct net *net, u8 daddr) { struct phonet_net *pnn = phonet_pernet(net); struct phonet_routes *routes = &pnn->routes; struct net_device *dev; daddr >>= 2; dev = rcu_dereference(routes->table[daddr]); return dev; } struct net_device *phonet_route_output(struct net *net, u8 daddr) { struct phonet_net *pnn = phonet_pernet(net); struct phonet_routes *routes = &pnn->routes; struct net_device *dev; daddr >>= 2; rcu_read_lock(); dev = rcu_dereference(routes->table[daddr]); dev_hold(dev); rcu_read_unlock(); if (!dev) dev = phonet_device_get(net); /* Default route */ return dev; }
linux-master
net/phonet/pn_dev.c
// SPDX-License-Identifier: GPL-2.0-only /* * File: pep-gprs.c * * GPRS over Phonet pipe end point socket * * Copyright (C) 2008 Nokia Corporation. * * Author: Rémi Denis-Courmont */ #include <linux/kernel.h> #include <linux/netdevice.h> #include <linux/if_ether.h> #include <linux/if_arp.h> #include <net/sock.h> #include <linux/if_phonet.h> #include <net/tcp_states.h> #include <net/phonet/gprs.h> #include <trace/events/sock.h> #define GPRS_DEFAULT_MTU 1400 struct gprs_dev { struct sock *sk; void (*old_state_change)(struct sock *); void (*old_data_ready)(struct sock *); void (*old_write_space)(struct sock *); struct net_device *dev; }; static __be16 gprs_type_trans(struct sk_buff *skb) { const u8 *pvfc; u8 buf; pvfc = skb_header_pointer(skb, 0, 1, &buf); if (!pvfc) return htons(0); /* Look at IP version field */ switch (*pvfc >> 4) { case 4: return htons(ETH_P_IP); case 6: return htons(ETH_P_IPV6); } return htons(0); } static void gprs_writeable(struct gprs_dev *gp) { struct net_device *dev = gp->dev; if (pep_writeable(gp->sk)) netif_wake_queue(dev); } /* * Socket callbacks */ static void gprs_state_change(struct sock *sk) { struct gprs_dev *gp = sk->sk_user_data; if (sk->sk_state == TCP_CLOSE_WAIT) { struct net_device *dev = gp->dev; netif_stop_queue(dev); netif_carrier_off(dev); } } static int gprs_recv(struct gprs_dev *gp, struct sk_buff *skb) { struct net_device *dev = gp->dev; int err = 0; __be16 protocol = gprs_type_trans(skb); if (!protocol) { err = -EINVAL; goto drop; } if (skb_headroom(skb) & 3) { struct sk_buff *rskb, *fs; int flen = 0; /* Phonet Pipe data header may be misaligned (3 bytes), * so wrap the IP packet as a single fragment of an head-less * socket buffer. The network stack will pull what it needs, * but at least, the whole IP payload is not memcpy'd. */ rskb = netdev_alloc_skb(dev, 0); if (!rskb) { err = -ENOBUFS; goto drop; } skb_shinfo(rskb)->frag_list = skb; rskb->len += skb->len; rskb->data_len += rskb->len; rskb->truesize += rskb->len; /* Avoid nested fragments */ skb_walk_frags(skb, fs) flen += fs->len; skb->next = skb_shinfo(skb)->frag_list; skb_frag_list_init(skb); skb->len -= flen; skb->data_len -= flen; skb->truesize -= flen; skb = rskb; } skb->protocol = protocol; skb_reset_mac_header(skb); skb->dev = dev; if (likely(dev->flags & IFF_UP)) { dev->stats.rx_packets++; dev->stats.rx_bytes += skb->len; netif_rx(skb); skb = NULL; } else err = -ENODEV; drop: if (skb) { dev_kfree_skb(skb); dev->stats.rx_dropped++; } return err; } static void gprs_data_ready(struct sock *sk) { struct gprs_dev *gp = sk->sk_user_data; struct sk_buff *skb; trace_sk_data_ready(sk); while ((skb = pep_read(sk)) != NULL) { skb_orphan(skb); gprs_recv(gp, skb); } } static void gprs_write_space(struct sock *sk) { struct gprs_dev *gp = sk->sk_user_data; if (netif_running(gp->dev)) gprs_writeable(gp); } /* * Network device callbacks */ static int gprs_open(struct net_device *dev) { struct gprs_dev *gp = netdev_priv(dev); gprs_writeable(gp); return 0; } static int gprs_close(struct net_device *dev) { netif_stop_queue(dev); return 0; } static netdev_tx_t gprs_xmit(struct sk_buff *skb, struct net_device *dev) { struct gprs_dev *gp = netdev_priv(dev); struct sock *sk = gp->sk; int len, err; switch (skb->protocol) { case htons(ETH_P_IP): case htons(ETH_P_IPV6): break; default: dev_kfree_skb(skb); return NETDEV_TX_OK; } skb_orphan(skb); skb_set_owner_w(skb, sk); len = skb->len; err = pep_write(sk, skb); if (err) { net_dbg_ratelimited("%s: TX error (%d)\n", dev->name, err); dev->stats.tx_aborted_errors++; dev->stats.tx_errors++; } else { dev->stats.tx_packets++; dev->stats.tx_bytes += len; } netif_stop_queue(dev); if (pep_writeable(sk)) netif_wake_queue(dev); return NETDEV_TX_OK; } static const struct net_device_ops gprs_netdev_ops = { .ndo_open = gprs_open, .ndo_stop = gprs_close, .ndo_start_xmit = gprs_xmit, }; static void gprs_setup(struct net_device *dev) { dev->features = NETIF_F_FRAGLIST; dev->type = ARPHRD_PHONET_PIPE; dev->flags = IFF_POINTOPOINT | IFF_NOARP; dev->mtu = GPRS_DEFAULT_MTU; dev->min_mtu = 576; dev->max_mtu = (PHONET_MAX_MTU - 11); dev->hard_header_len = 0; dev->addr_len = 0; dev->tx_queue_len = 10; dev->netdev_ops = &gprs_netdev_ops; dev->needs_free_netdev = true; } /* * External interface */ /* * Attach a GPRS interface to a datagram socket. * Returns the interface index on success, negative error code on error. */ int gprs_attach(struct sock *sk) { static const char ifname[] = "gprs%d"; struct gprs_dev *gp; struct net_device *dev; int err; if (unlikely(sk->sk_type == SOCK_STREAM)) return -EINVAL; /* need packet boundaries */ /* Create net device */ dev = alloc_netdev(sizeof(*gp), ifname, NET_NAME_UNKNOWN, gprs_setup); if (!dev) return -ENOMEM; gp = netdev_priv(dev); gp->sk = sk; gp->dev = dev; netif_stop_queue(dev); err = register_netdev(dev); if (err) { free_netdev(dev); return err; } lock_sock(sk); if (unlikely(sk->sk_user_data)) { err = -EBUSY; goto out_rel; } if (unlikely((1 << sk->sk_state & (TCPF_CLOSE|TCPF_LISTEN)) || sock_flag(sk, SOCK_DEAD))) { err = -EINVAL; goto out_rel; } sk->sk_user_data = gp; gp->old_state_change = sk->sk_state_change; gp->old_data_ready = sk->sk_data_ready; gp->old_write_space = sk->sk_write_space; sk->sk_state_change = gprs_state_change; sk->sk_data_ready = gprs_data_ready; sk->sk_write_space = gprs_write_space; release_sock(sk); sock_hold(sk); printk(KERN_DEBUG"%s: attached\n", dev->name); return dev->ifindex; out_rel: release_sock(sk); unregister_netdev(dev); return err; } void gprs_detach(struct sock *sk) { struct gprs_dev *gp = sk->sk_user_data; struct net_device *dev = gp->dev; lock_sock(sk); sk->sk_user_data = NULL; sk->sk_state_change = gp->old_state_change; sk->sk_data_ready = gp->old_data_ready; sk->sk_write_space = gp->old_write_space; release_sock(sk); printk(KERN_DEBUG"%s: detached\n", dev->name); unregister_netdev(dev); sock_put(sk); }
linux-master
net/phonet/pep-gprs.c
// SPDX-License-Identifier: GPL-2.0-only /* * File: af_phonet.c * * Phonet protocols family * * Copyright (C) 2008 Nokia Corporation. * * Authors: Sakari Ailus <[email protected]> * Rémi Denis-Courmont */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/slab.h> #include <asm/unaligned.h> #include <net/sock.h> #include <linux/if_phonet.h> #include <linux/phonet.h> #include <net/phonet/phonet.h> #include <net/phonet/pn_dev.h> /* Transport protocol registration */ static const struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly; static const struct phonet_protocol *phonet_proto_get(unsigned int protocol) { const struct phonet_protocol *pp; if (protocol >= PHONET_NPROTO) return NULL; rcu_read_lock(); pp = rcu_dereference(proto_tab[protocol]); if (pp && !try_module_get(pp->prot->owner)) pp = NULL; rcu_read_unlock(); return pp; } static inline void phonet_proto_put(const struct phonet_protocol *pp) { module_put(pp->prot->owner); } /* protocol family functions */ static int pn_socket_create(struct net *net, struct socket *sock, int protocol, int kern) { struct sock *sk; struct pn_sock *pn; const struct phonet_protocol *pnp; int err; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (protocol == 0) { /* Default protocol selection */ switch (sock->type) { case SOCK_DGRAM: protocol = PN_PROTO_PHONET; break; case SOCK_SEQPACKET: protocol = PN_PROTO_PIPE; break; default: return -EPROTONOSUPPORT; } } pnp = phonet_proto_get(protocol); if (pnp == NULL && request_module("net-pf-%d-proto-%d", PF_PHONET, protocol) == 0) pnp = phonet_proto_get(protocol); if (pnp == NULL) return -EPROTONOSUPPORT; if (sock->type != pnp->sock_type) { err = -EPROTONOSUPPORT; goto out; } sk = sk_alloc(net, PF_PHONET, GFP_KERNEL, pnp->prot, kern); if (sk == NULL) { err = -ENOMEM; goto out; } sock_init_data(sock, sk); sock->state = SS_UNCONNECTED; sock->ops = pnp->ops; sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv; sk->sk_protocol = protocol; pn = pn_sk(sk); pn->sobject = 0; pn->dobject = 0; pn->resource = 0; sk->sk_prot->init(sk); err = 0; out: phonet_proto_put(pnp); return err; } static const struct net_proto_family phonet_proto_family = { .family = PF_PHONET, .create = pn_socket_create, .owner = THIS_MODULE, }; /* Phonet device header operations */ static int pn_header_create(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) { u8 *media = skb_push(skb, 1); if (type != ETH_P_PHONET) return -1; if (!saddr) saddr = dev->dev_addr; *media = *(const u8 *)saddr; return 1; } static int pn_header_parse(const struct sk_buff *skb, unsigned char *haddr) { const u8 *media = skb_mac_header(skb); *haddr = *media; return 1; } const struct header_ops phonet_header_ops = { .create = pn_header_create, .parse = pn_header_parse, }; EXPORT_SYMBOL(phonet_header_ops); /* * Prepends an ISI header and sends a datagram. */ static int pn_send(struct sk_buff *skb, struct net_device *dev, u16 dst, u16 src, u8 res) { struct phonethdr *ph; int err; if (skb->len + 2 > 0xffff /* Phonet length field limit */ || skb->len + sizeof(struct phonethdr) > dev->mtu) { err = -EMSGSIZE; goto drop; } /* Broadcast sending is not implemented */ if (pn_addr(dst) == PNADDR_BROADCAST) { err = -EOPNOTSUPP; goto drop; } skb_reset_transport_header(skb); WARN_ON(skb_headroom(skb) & 1); /* HW assumes word alignment */ skb_push(skb, sizeof(struct phonethdr)); skb_reset_network_header(skb); ph = pn_hdr(skb); ph->pn_rdev = pn_dev(dst); ph->pn_sdev = pn_dev(src); ph->pn_res = res; ph->pn_length = __cpu_to_be16(skb->len + 2 - sizeof(*ph)); ph->pn_robj = pn_obj(dst); ph->pn_sobj = pn_obj(src); skb->protocol = htons(ETH_P_PHONET); skb->priority = 0; skb->dev = dev; if (skb->pkt_type == PACKET_LOOPBACK) { skb_reset_mac_header(skb); skb_orphan(skb); err = netif_rx(skb) ? -ENOBUFS : 0; } else { err = dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL, skb->len); if (err < 0) { err = -EHOSTUNREACH; goto drop; } err = dev_queue_xmit(skb); if (unlikely(err > 0)) err = net_xmit_errno(err); } return err; drop: kfree_skb(skb); return err; } static int pn_raw_send(const void *data, int len, struct net_device *dev, u16 dst, u16 src, u8 res) { struct sk_buff *skb = alloc_skb(MAX_PHONET_HEADER + len, GFP_ATOMIC); if (skb == NULL) return -ENOMEM; if (phonet_address_lookup(dev_net(dev), pn_addr(dst)) == 0) skb->pkt_type = PACKET_LOOPBACK; skb_reserve(skb, MAX_PHONET_HEADER); __skb_put(skb, len); skb_copy_to_linear_data(skb, data, len); return pn_send(skb, dev, dst, src, res); } /* * Create a Phonet header for the skb and send it out. Returns * non-zero error code if failed. The skb is freed then. */ int pn_skb_send(struct sock *sk, struct sk_buff *skb, const struct sockaddr_pn *target) { struct net *net = sock_net(sk); struct net_device *dev; struct pn_sock *pn = pn_sk(sk); int err; u16 src, dst; u8 daddr, saddr, res; src = pn->sobject; if (target != NULL) { dst = pn_sockaddr_get_object(target); res = pn_sockaddr_get_resource(target); } else { dst = pn->dobject; res = pn->resource; } daddr = pn_addr(dst); err = -EHOSTUNREACH; if (sk->sk_bound_dev_if) dev = dev_get_by_index(net, sk->sk_bound_dev_if); else if (phonet_address_lookup(net, daddr) == 0) { dev = phonet_device_get(net); skb->pkt_type = PACKET_LOOPBACK; } else if (dst == 0) { /* Resource routing (small race until phonet_rcv()) */ struct sock *sk = pn_find_sock_by_res(net, res); if (sk) { sock_put(sk); dev = phonet_device_get(net); skb->pkt_type = PACKET_LOOPBACK; } else dev = phonet_route_output(net, daddr); } else dev = phonet_route_output(net, daddr); if (!dev || !(dev->flags & IFF_UP)) goto drop; saddr = phonet_address_get(dev, daddr); if (saddr == PN_NO_ADDR) goto drop; if (!pn_addr(src)) src = pn_object(saddr, pn_obj(src)); err = pn_send(skb, dev, dst, src, res); dev_put(dev); return err; drop: kfree_skb(skb); dev_put(dev); return err; } EXPORT_SYMBOL(pn_skb_send); /* Do not send an error message in response to an error message */ static inline int can_respond(struct sk_buff *skb) { const struct phonethdr *ph; const struct phonetmsg *pm; u8 submsg_id; if (!pskb_may_pull(skb, 3)) return 0; ph = pn_hdr(skb); if (ph->pn_res == PN_PREFIX && !pskb_may_pull(skb, 5)) return 0; if (ph->pn_res == PN_COMMGR) /* indications */ return 0; ph = pn_hdr(skb); /* re-acquires the pointer */ pm = pn_msg(skb); if (pm->pn_msg_id != PN_COMMON_MESSAGE) return 1; submsg_id = (ph->pn_res == PN_PREFIX) ? pm->pn_e_submsg_id : pm->pn_submsg_id; if (submsg_id != PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP && pm->pn_e_submsg_id != PN_COMM_SERVICE_NOT_IDENTIFIED_RESP) return 1; return 0; } static int send_obj_unreachable(struct sk_buff *rskb) { const struct phonethdr *oph = pn_hdr(rskb); const struct phonetmsg *opm = pn_msg(rskb); struct phonetmsg resp; memset(&resp, 0, sizeof(resp)); resp.pn_trans_id = opm->pn_trans_id; resp.pn_msg_id = PN_COMMON_MESSAGE; if (oph->pn_res == PN_PREFIX) { resp.pn_e_res_id = opm->pn_e_res_id; resp.pn_e_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP; resp.pn_e_orig_msg_id = opm->pn_msg_id; resp.pn_e_status = 0; } else { resp.pn_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP; resp.pn_orig_msg_id = opm->pn_msg_id; resp.pn_status = 0; } return pn_raw_send(&resp, sizeof(resp), rskb->dev, pn_object(oph->pn_sdev, oph->pn_sobj), pn_object(oph->pn_rdev, oph->pn_robj), oph->pn_res); } static int send_reset_indications(struct sk_buff *rskb) { struct phonethdr *oph = pn_hdr(rskb); static const u8 data[4] = { 0x00 /* trans ID */, 0x10 /* subscribe msg */, 0x00 /* subscription count */, 0x00 /* dummy */ }; return pn_raw_send(data, sizeof(data), rskb->dev, pn_object(oph->pn_sdev, 0x00), pn_object(oph->pn_rdev, oph->pn_robj), PN_COMMGR); } /* packet type functions */ /* * Stuff received packets to associated sockets. * On error, returns non-zero and releases the skb. */ static int phonet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pkttype, struct net_device *orig_dev) { struct net *net = dev_net(dev); struct phonethdr *ph; struct sockaddr_pn sa; u16 len; skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) return NET_RX_DROP; /* check we have at least a full Phonet header */ if (!pskb_pull(skb, sizeof(struct phonethdr))) goto out; /* check that the advertised length is correct */ ph = pn_hdr(skb); len = get_unaligned_be16(&ph->pn_length); if (len < 2) goto out; len -= 2; if ((len > skb->len) || pskb_trim(skb, len)) goto out; skb_reset_transport_header(skb); pn_skb_get_dst_sockaddr(skb, &sa); /* check if this is broadcasted */ if (pn_sockaddr_get_addr(&sa) == PNADDR_BROADCAST) { pn_deliver_sock_broadcast(net, skb); goto out; } /* resource routing */ if (pn_sockaddr_get_object(&sa) == 0) { struct sock *sk = pn_find_sock_by_res(net, sa.spn_resource); if (sk) return sk_receive_skb(sk, skb, 0); } /* check if we are the destination */ if (phonet_address_lookup(net, pn_sockaddr_get_addr(&sa)) == 0) { /* Phonet packet input */ struct sock *sk = pn_find_sock_by_sa(net, &sa); if (sk) return sk_receive_skb(sk, skb, 0); if (can_respond(skb)) { send_obj_unreachable(skb); send_reset_indications(skb); } } else if (unlikely(skb->pkt_type == PACKET_LOOPBACK)) goto out; /* Race between address deletion and loopback */ else { /* Phonet packet routing */ struct net_device *out_dev; out_dev = phonet_route_output(net, pn_sockaddr_get_addr(&sa)); if (!out_dev) { net_dbg_ratelimited("No Phonet route to %02X\n", pn_sockaddr_get_addr(&sa)); goto out; } __skb_push(skb, sizeof(struct phonethdr)); skb->dev = out_dev; if (out_dev == dev) { net_dbg_ratelimited("Phonet loop to %02X on %s\n", pn_sockaddr_get_addr(&sa), dev->name); goto out_dev; } /* Some drivers (e.g. TUN) do not allocate HW header space */ if (skb_cow_head(skb, out_dev->hard_header_len)) goto out_dev; if (dev_hard_header(skb, out_dev, ETH_P_PHONET, NULL, NULL, skb->len) < 0) goto out_dev; dev_queue_xmit(skb); dev_put(out_dev); return NET_RX_SUCCESS; out_dev: dev_put(out_dev); } out: kfree_skb(skb); return NET_RX_DROP; } static struct packet_type phonet_packet_type __read_mostly = { .type = cpu_to_be16(ETH_P_PHONET), .func = phonet_rcv, }; static DEFINE_MUTEX(proto_tab_lock); int __init_or_module phonet_proto_register(unsigned int protocol, const struct phonet_protocol *pp) { int err = 0; if (protocol >= PHONET_NPROTO) return -EINVAL; err = proto_register(pp->prot, 1); if (err) return err; mutex_lock(&proto_tab_lock); if (proto_tab[protocol]) err = -EBUSY; else rcu_assign_pointer(proto_tab[protocol], pp); mutex_unlock(&proto_tab_lock); return err; } EXPORT_SYMBOL(phonet_proto_register); void phonet_proto_unregister(unsigned int protocol, const struct phonet_protocol *pp) { mutex_lock(&proto_tab_lock); BUG_ON(proto_tab[protocol] != pp); RCU_INIT_POINTER(proto_tab[protocol], NULL); mutex_unlock(&proto_tab_lock); synchronize_rcu(); proto_unregister(pp->prot); } EXPORT_SYMBOL(phonet_proto_unregister); /* Module registration */ static int __init phonet_init(void) { int err; err = phonet_device_init(); if (err) return err; pn_sock_init(); err = sock_register(&phonet_proto_family); if (err) { printk(KERN_ALERT "phonet protocol family initialization failed\n"); goto err_sock; } dev_add_pack(&phonet_packet_type); phonet_sysctl_init(); err = isi_register(); if (err) goto err; return 0; err: phonet_sysctl_exit(); sock_unregister(PF_PHONET); dev_remove_pack(&phonet_packet_type); err_sock: phonet_device_exit(); return err; } static void __exit phonet_exit(void) { isi_unregister(); phonet_sysctl_exit(); sock_unregister(PF_PHONET); dev_remove_pack(&phonet_packet_type); phonet_device_exit(); } module_init(phonet_init); module_exit(phonet_exit); MODULE_DESCRIPTION("Phonet protocol stack for Linux"); MODULE_LICENSE("GPL"); MODULE_ALIAS_NETPROTO(PF_PHONET);
linux-master
net/phonet/af_phonet.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NetLabel Unlabeled Support * * This file defines functions for dealing with unlabeled packets for the * NetLabel system. The NetLabel system manages static and dynamic label * mappings for network protocols such as CIPSO and RIPSO. * * Author: Paul Moore <[email protected]> */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 - 2008 */ #include <linux/types.h> #include <linux/rcupdate.h> #include <linux/list.h> #include <linux/spinlock.h> #include <linux/socket.h> #include <linux/string.h> #include <linux/skbuff.h> #include <linux/audit.h> #include <linux/in.h> #include <linux/in6.h> #include <linux/ip.h> #include <linux/ipv6.h> #include <linux/notifier.h> #include <linux/netdevice.h> #include <linux/security.h> #include <linux/slab.h> #include <net/sock.h> #include <net/netlink.h> #include <net/genetlink.h> #include <net/ip.h> #include <net/ipv6.h> #include <net/net_namespace.h> #include <net/netlabel.h> #include <asm/bug.h> #include <linux/atomic.h> #include "netlabel_user.h" #include "netlabel_addrlist.h" #include "netlabel_domainhash.h" #include "netlabel_unlabeled.h" #include "netlabel_mgmt.h" /* NOTE: at present we always use init's network namespace since we don't * presently support different namespaces even though the majority of * the functions in this file are "namespace safe" */ /* The unlabeled connection hash table which we use to map network interfaces * and addresses of unlabeled packets to a user specified secid value for the * LSM. The hash table is used to lookup the network interface entry * (struct netlbl_unlhsh_iface) and then the interface entry is used to * lookup an IP address match from an ordered list. If a network interface * match can not be found in the hash table then the default entry * (netlbl_unlhsh_def) is used. The IP address entry list * (struct netlbl_unlhsh_addr) is ordered such that the entries with a * larger netmask come first. */ struct netlbl_unlhsh_tbl { struct list_head *tbl; u32 size; }; #define netlbl_unlhsh_addr4_entry(iter) \ container_of(iter, struct netlbl_unlhsh_addr4, list) struct netlbl_unlhsh_addr4 { u32 secid; struct netlbl_af4list list; struct rcu_head rcu; }; #define netlbl_unlhsh_addr6_entry(iter) \ container_of(iter, struct netlbl_unlhsh_addr6, list) struct netlbl_unlhsh_addr6 { u32 secid; struct netlbl_af6list list; struct rcu_head rcu; }; struct netlbl_unlhsh_iface { int ifindex; struct list_head addr4_list; struct list_head addr6_list; u32 valid; struct list_head list; struct rcu_head rcu; }; /* Argument struct for netlbl_unlhsh_walk() */ struct netlbl_unlhsh_walk_arg { struct netlink_callback *nl_cb; struct sk_buff *skb; u32 seq; }; /* Unlabeled connection hash table */ /* updates should be so rare that having one spinlock for the entire * hash table should be okay */ static DEFINE_SPINLOCK(netlbl_unlhsh_lock); #define netlbl_unlhsh_rcu_deref(p) \ rcu_dereference_check(p, lockdep_is_held(&netlbl_unlhsh_lock)) static struct netlbl_unlhsh_tbl __rcu *netlbl_unlhsh; static struct netlbl_unlhsh_iface __rcu *netlbl_unlhsh_def; /* Accept unlabeled packets flag */ static u8 netlabel_unlabel_acceptflg; /* NetLabel Generic NETLINK unlabeled family */ static struct genl_family netlbl_unlabel_gnl_family; /* NetLabel Netlink attribute policy */ static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = { [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 }, [NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY, .len = sizeof(struct in6_addr) }, [NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY, .len = sizeof(struct in6_addr) }, [NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY, .len = sizeof(struct in_addr) }, [NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY, .len = sizeof(struct in_addr) }, [NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 }, [NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY } }; /* * Unlabeled Connection Hash Table Functions */ /** * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table * @entry: the entry's RCU field * * Description: * This function is designed to be used as a callback to the call_rcu() * function so that memory allocated to a hash table interface entry can be * released safely. It is important to note that this function does not free * the IPv4 and IPv6 address lists contained as part of an interface entry. It * is up to the rest of the code to make sure an interface entry is only freed * once it's address lists are empty. * */ static void netlbl_unlhsh_free_iface(struct rcu_head *entry) { struct netlbl_unlhsh_iface *iface; struct netlbl_af4list *iter4; struct netlbl_af4list *tmp4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *iter6; struct netlbl_af6list *tmp6; #endif /* IPv6 */ iface = container_of(entry, struct netlbl_unlhsh_iface, rcu); /* no need for locks here since we are the only one with access to this * structure */ netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) { netlbl_af4list_remove_entry(iter4); kfree(netlbl_unlhsh_addr4_entry(iter4)); } #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) { netlbl_af6list_remove_entry(iter6); kfree(netlbl_unlhsh_addr6_entry(iter6)); } #endif /* IPv6 */ kfree(iface); } /** * netlbl_unlhsh_hash - Hashing function for the hash table * @ifindex: the network interface/device to hash * * Description: * This is the hashing function for the unlabeled hash table, it returns the * bucket number for the given device/interface. The caller is responsible for * ensuring that the hash table is protected with either a RCU read lock or * the hash table lock. * */ static u32 netlbl_unlhsh_hash(int ifindex) { return ifindex & (netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->size - 1); } /** * netlbl_unlhsh_search_iface - Search for a matching interface entry * @ifindex: the network interface * * Description: * Searches the unlabeled connection hash table and returns a pointer to the * interface entry which matches @ifindex, otherwise NULL is returned. The * caller is responsible for ensuring that the hash table is protected with * either a RCU read lock or the hash table lock. * */ static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex) { u32 bkt; struct list_head *bkt_list; struct netlbl_unlhsh_iface *iter; bkt = netlbl_unlhsh_hash(ifindex); bkt_list = &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]; list_for_each_entry_rcu(iter, bkt_list, list, lockdep_is_held(&netlbl_unlhsh_lock)) if (iter->valid && iter->ifindex == ifindex) return iter; return NULL; } /** * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table * @iface: the associated interface entry * @addr: IPv4 address in network byte order * @mask: IPv4 address mask in network byte order * @secid: LSM secid value for entry * * Description: * Add a new address entry into the unlabeled connection hash table using the * interface entry specified by @iface. On success zero is returned, otherwise * a negative value is returned. * */ static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface, const struct in_addr *addr, const struct in_addr *mask, u32 secid) { int ret_val; struct netlbl_unlhsh_addr4 *entry; entry = kzalloc(sizeof(*entry), GFP_ATOMIC); if (entry == NULL) return -ENOMEM; entry->list.addr = addr->s_addr & mask->s_addr; entry->list.mask = mask->s_addr; entry->list.valid = 1; entry->secid = secid; spin_lock(&netlbl_unlhsh_lock); ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list); spin_unlock(&netlbl_unlhsh_lock); if (ret_val != 0) kfree(entry); return ret_val; } #if IS_ENABLED(CONFIG_IPV6) /** * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table * @iface: the associated interface entry * @addr: IPv6 address in network byte order * @mask: IPv6 address mask in network byte order * @secid: LSM secid value for entry * * Description: * Add a new address entry into the unlabeled connection hash table using the * interface entry specified by @iface. On success zero is returned, otherwise * a negative value is returned. * */ static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface, const struct in6_addr *addr, const struct in6_addr *mask, u32 secid) { int ret_val; struct netlbl_unlhsh_addr6 *entry; entry = kzalloc(sizeof(*entry), GFP_ATOMIC); if (entry == NULL) return -ENOMEM; entry->list.addr = *addr; entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0]; entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1]; entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2]; entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3]; entry->list.mask = *mask; entry->list.valid = 1; entry->secid = secid; spin_lock(&netlbl_unlhsh_lock); ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list); spin_unlock(&netlbl_unlhsh_lock); if (ret_val != 0) kfree(entry); return 0; } #endif /* IPv6 */ /** * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table * @ifindex: network interface * * Description: * Add a new, empty, interface entry into the unlabeled connection hash table. * On success a pointer to the new interface entry is returned, on failure NULL * is returned. * */ static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex) { u32 bkt; struct netlbl_unlhsh_iface *iface; iface = kzalloc(sizeof(*iface), GFP_ATOMIC); if (iface == NULL) return NULL; iface->ifindex = ifindex; INIT_LIST_HEAD(&iface->addr4_list); INIT_LIST_HEAD(&iface->addr6_list); iface->valid = 1; spin_lock(&netlbl_unlhsh_lock); if (ifindex > 0) { bkt = netlbl_unlhsh_hash(ifindex); if (netlbl_unlhsh_search_iface(ifindex) != NULL) goto add_iface_failure; list_add_tail_rcu(&iface->list, &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]); } else { INIT_LIST_HEAD(&iface->list); if (netlbl_unlhsh_rcu_deref(netlbl_unlhsh_def) != NULL) goto add_iface_failure; rcu_assign_pointer(netlbl_unlhsh_def, iface); } spin_unlock(&netlbl_unlhsh_lock); return iface; add_iface_failure: spin_unlock(&netlbl_unlhsh_lock); kfree(iface); return NULL; } /** * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table * @net: network namespace * @dev_name: interface name * @addr: IP address in network byte order * @mask: address mask in network byte order * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6) * @secid: LSM secid value for the entry * @audit_info: NetLabel audit information * * Description: * Adds a new entry to the unlabeled connection hash table. Returns zero on * success, negative values on failure. * */ int netlbl_unlhsh_add(struct net *net, const char *dev_name, const void *addr, const void *mask, u32 addr_len, u32 secid, struct netlbl_audit *audit_info) { int ret_val; int ifindex; struct net_device *dev; struct netlbl_unlhsh_iface *iface; struct audit_buffer *audit_buf = NULL; char *secctx = NULL; u32 secctx_len; if (addr_len != sizeof(struct in_addr) && addr_len != sizeof(struct in6_addr)) return -EINVAL; rcu_read_lock(); if (dev_name != NULL) { dev = dev_get_by_name_rcu(net, dev_name); if (dev == NULL) { ret_val = -ENODEV; goto unlhsh_add_return; } ifindex = dev->ifindex; iface = netlbl_unlhsh_search_iface(ifindex); } else { ifindex = 0; iface = rcu_dereference(netlbl_unlhsh_def); } if (iface == NULL) { iface = netlbl_unlhsh_add_iface(ifindex); if (iface == NULL) { ret_val = -ENOMEM; goto unlhsh_add_return; } } audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD, audit_info); switch (addr_len) { case sizeof(struct in_addr): { const struct in_addr *addr4 = addr; const struct in_addr *mask4 = mask; ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid); if (audit_buf != NULL) netlbl_af4list_audit_addr(audit_buf, 1, dev_name, addr4->s_addr, mask4->s_addr); break; } #if IS_ENABLED(CONFIG_IPV6) case sizeof(struct in6_addr): { const struct in6_addr *addr6 = addr; const struct in6_addr *mask6 = mask; ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid); if (audit_buf != NULL) netlbl_af6list_audit_addr(audit_buf, 1, dev_name, addr6, mask6); break; } #endif /* IPv6 */ default: ret_val = -EINVAL; } if (ret_val == 0) atomic_inc(&netlabel_mgmt_protocount); unlhsh_add_return: rcu_read_unlock(); if (audit_buf != NULL) { if (security_secid_to_secctx(secid, &secctx, &secctx_len) == 0) { audit_log_format(audit_buf, " sec_obj=%s", secctx); security_release_secctx(secctx, secctx_len); } audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0); audit_log_end(audit_buf); } return ret_val; } /** * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry * @net: network namespace * @iface: interface entry * @addr: IP address * @mask: IP address mask * @audit_info: NetLabel audit information * * Description: * Remove an IP address entry from the unlabeled connection hash table. * Returns zero on success, negative values on failure. * */ static int netlbl_unlhsh_remove_addr4(struct net *net, struct netlbl_unlhsh_iface *iface, const struct in_addr *addr, const struct in_addr *mask, struct netlbl_audit *audit_info) { struct netlbl_af4list *list_entry; struct netlbl_unlhsh_addr4 *entry; struct audit_buffer *audit_buf; struct net_device *dev; char *secctx; u32 secctx_len; spin_lock(&netlbl_unlhsh_lock); list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr, &iface->addr4_list); spin_unlock(&netlbl_unlhsh_lock); if (list_entry != NULL) entry = netlbl_unlhsh_addr4_entry(list_entry); else entry = NULL; audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL, audit_info); if (audit_buf != NULL) { dev = dev_get_by_index(net, iface->ifindex); netlbl_af4list_audit_addr(audit_buf, 1, (dev != NULL ? dev->name : NULL), addr->s_addr, mask->s_addr); dev_put(dev); if (entry != NULL && security_secid_to_secctx(entry->secid, &secctx, &secctx_len) == 0) { audit_log_format(audit_buf, " sec_obj=%s", secctx); security_release_secctx(secctx, secctx_len); } audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0); audit_log_end(audit_buf); } if (entry == NULL) return -ENOENT; kfree_rcu(entry, rcu); return 0; } #if IS_ENABLED(CONFIG_IPV6) /** * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry * @net: network namespace * @iface: interface entry * @addr: IP address * @mask: IP address mask * @audit_info: NetLabel audit information * * Description: * Remove an IP address entry from the unlabeled connection hash table. * Returns zero on success, negative values on failure. * */ static int netlbl_unlhsh_remove_addr6(struct net *net, struct netlbl_unlhsh_iface *iface, const struct in6_addr *addr, const struct in6_addr *mask, struct netlbl_audit *audit_info) { struct netlbl_af6list *list_entry; struct netlbl_unlhsh_addr6 *entry; struct audit_buffer *audit_buf; struct net_device *dev; char *secctx; u32 secctx_len; spin_lock(&netlbl_unlhsh_lock); list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list); spin_unlock(&netlbl_unlhsh_lock); if (list_entry != NULL) entry = netlbl_unlhsh_addr6_entry(list_entry); else entry = NULL; audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL, audit_info); if (audit_buf != NULL) { dev = dev_get_by_index(net, iface->ifindex); netlbl_af6list_audit_addr(audit_buf, 1, (dev != NULL ? dev->name : NULL), addr, mask); dev_put(dev); if (entry != NULL && security_secid_to_secctx(entry->secid, &secctx, &secctx_len) == 0) { audit_log_format(audit_buf, " sec_obj=%s", secctx); security_release_secctx(secctx, secctx_len); } audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0); audit_log_end(audit_buf); } if (entry == NULL) return -ENOENT; kfree_rcu(entry, rcu); return 0; } #endif /* IPv6 */ /** * netlbl_unlhsh_condremove_iface - Remove an interface entry * @iface: the interface entry * * Description: * Remove an interface entry from the unlabeled connection hash table if it is * empty. An interface entry is considered to be empty if there are no * address entries assigned to it. * */ static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface) { struct netlbl_af4list *iter4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *iter6; #endif /* IPv6 */ spin_lock(&netlbl_unlhsh_lock); netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list) goto unlhsh_condremove_failure; #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list) goto unlhsh_condremove_failure; #endif /* IPv6 */ iface->valid = 0; if (iface->ifindex > 0) list_del_rcu(&iface->list); else RCU_INIT_POINTER(netlbl_unlhsh_def, NULL); spin_unlock(&netlbl_unlhsh_lock); call_rcu(&iface->rcu, netlbl_unlhsh_free_iface); return; unlhsh_condremove_failure: spin_unlock(&netlbl_unlhsh_lock); } /** * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table * @net: network namespace * @dev_name: interface name * @addr: IP address in network byte order * @mask: address mask in network byte order * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6) * @audit_info: NetLabel audit information * * Description: * Removes and existing entry from the unlabeled connection hash table. * Returns zero on success, negative values on failure. * */ int netlbl_unlhsh_remove(struct net *net, const char *dev_name, const void *addr, const void *mask, u32 addr_len, struct netlbl_audit *audit_info) { int ret_val; struct net_device *dev; struct netlbl_unlhsh_iface *iface; if (addr_len != sizeof(struct in_addr) && addr_len != sizeof(struct in6_addr)) return -EINVAL; rcu_read_lock(); if (dev_name != NULL) { dev = dev_get_by_name_rcu(net, dev_name); if (dev == NULL) { ret_val = -ENODEV; goto unlhsh_remove_return; } iface = netlbl_unlhsh_search_iface(dev->ifindex); } else iface = rcu_dereference(netlbl_unlhsh_def); if (iface == NULL) { ret_val = -ENOENT; goto unlhsh_remove_return; } switch (addr_len) { case sizeof(struct in_addr): ret_val = netlbl_unlhsh_remove_addr4(net, iface, addr, mask, audit_info); break; #if IS_ENABLED(CONFIG_IPV6) case sizeof(struct in6_addr): ret_val = netlbl_unlhsh_remove_addr6(net, iface, addr, mask, audit_info); break; #endif /* IPv6 */ default: ret_val = -EINVAL; } if (ret_val == 0) { netlbl_unlhsh_condremove_iface(iface); atomic_dec(&netlabel_mgmt_protocount); } unlhsh_remove_return: rcu_read_unlock(); return ret_val; } /* * General Helper Functions */ /** * netlbl_unlhsh_netdev_handler - Network device notification handler * @this: notifier block * @event: the event * @ptr: the netdevice notifier info (cast to void) * * Description: * Handle network device events, although at present all we care about is a * network device going away. In the case of a device going away we clear any * related entries from the unlabeled connection hash table. * */ static int netlbl_unlhsh_netdev_handler(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct netlbl_unlhsh_iface *iface = NULL; if (!net_eq(dev_net(dev), &init_net)) return NOTIFY_DONE; /* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */ if (event == NETDEV_DOWN) { spin_lock(&netlbl_unlhsh_lock); iface = netlbl_unlhsh_search_iface(dev->ifindex); if (iface != NULL && iface->valid) { iface->valid = 0; list_del_rcu(&iface->list); } else iface = NULL; spin_unlock(&netlbl_unlhsh_lock); } if (iface != NULL) call_rcu(&iface->rcu, netlbl_unlhsh_free_iface); return NOTIFY_DONE; } /** * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag * @value: desired value * @audit_info: NetLabel audit information * * Description: * Set the value of the unlabeled accept flag to @value. * */ static void netlbl_unlabel_acceptflg_set(u8 value, struct netlbl_audit *audit_info) { struct audit_buffer *audit_buf; u8 old_val; old_val = netlabel_unlabel_acceptflg; netlabel_unlabel_acceptflg = value; audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW, audit_info); if (audit_buf != NULL) { audit_log_format(audit_buf, " unlbl_accept=%u old=%u", value, old_val); audit_log_end(audit_buf); } } /** * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information * @info: the Generic NETLINK info block * @addr: the IP address * @mask: the IP address mask * @len: the address length * * Description: * Examine the Generic NETLINK message and extract the IP address information. * Returns zero on success, negative values on failure. * */ static int netlbl_unlabel_addrinfo_get(struct genl_info *info, void **addr, void **mask, u32 *len) { u32 addr_len; if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR] && info->attrs[NLBL_UNLABEL_A_IPV4MASK]) { addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]); if (addr_len != sizeof(struct in_addr) && addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK])) return -EINVAL; *len = addr_len; *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]); *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]); return 0; } else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) { addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]); if (addr_len != sizeof(struct in6_addr) && addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK])) return -EINVAL; *len = addr_len; *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]); *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]); return 0; } return -EINVAL; } /* * NetLabel Command Handlers */ /** * netlbl_unlabel_accept - Handle an ACCEPT message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated ACCEPT message and set the accept flag accordingly. * Returns zero on success, negative values on failure. * */ static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info) { u8 value; struct netlbl_audit audit_info; if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) { value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]); if (value == 1 || value == 0) { netlbl_netlink_auditinfo(&audit_info); netlbl_unlabel_acceptflg_set(value, &audit_info); return 0; } } return -EINVAL; } /** * netlbl_unlabel_list - Handle a LIST message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated LIST message and respond with the current status. * Returns zero on success, negative values on failure. * */ static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info) { int ret_val = -EINVAL; struct sk_buff *ans_skb; void *data; ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (ans_skb == NULL) goto list_failure; data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family, 0, NLBL_UNLABEL_C_LIST); if (data == NULL) { ret_val = -ENOMEM; goto list_failure; } ret_val = nla_put_u8(ans_skb, NLBL_UNLABEL_A_ACPTFLG, netlabel_unlabel_acceptflg); if (ret_val != 0) goto list_failure; genlmsg_end(ans_skb, data); return genlmsg_reply(ans_skb, info); list_failure: kfree_skb(ans_skb); return ret_val; } /** * netlbl_unlabel_staticadd - Handle a STATICADD message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated STATICADD message and add a new unlabeled * connection entry to the hash table. Returns zero on success, negative * values on failure. * */ static int netlbl_unlabel_staticadd(struct sk_buff *skb, struct genl_info *info) { int ret_val; char *dev_name; void *addr; void *mask; u32 addr_len; u32 secid; struct netlbl_audit audit_info; /* Don't allow users to add both IPv4 and IPv6 addresses for a * single entry. However, allow users to create two entries, one each * for IPv4 and IPv6, with the same LSM security context which should * achieve the same result. */ if (!info->attrs[NLBL_UNLABEL_A_SECCTX] || !info->attrs[NLBL_UNLABEL_A_IFACE] || !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] || !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^ (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] || !info->attrs[NLBL_UNLABEL_A_IPV6MASK]))) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len); if (ret_val != 0) return ret_val; dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]); ret_val = security_secctx_to_secid( nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]), nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]), &secid); if (ret_val != 0) return ret_val; return netlbl_unlhsh_add(&init_net, dev_name, addr, mask, addr_len, secid, &audit_info); } /** * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated STATICADDDEF message and add a new default * unlabeled connection entry. Returns zero on success, negative values on * failure. * */ static int netlbl_unlabel_staticadddef(struct sk_buff *skb, struct genl_info *info) { int ret_val; void *addr; void *mask; u32 addr_len; u32 secid; struct netlbl_audit audit_info; /* Don't allow users to add both IPv4 and IPv6 addresses for a * single entry. However, allow users to create two entries, one each * for IPv4 and IPv6, with the same LSM security context which should * achieve the same result. */ if (!info->attrs[NLBL_UNLABEL_A_SECCTX] || !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] || !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^ (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] || !info->attrs[NLBL_UNLABEL_A_IPV6MASK]))) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len); if (ret_val != 0) return ret_val; ret_val = security_secctx_to_secid( nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]), nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]), &secid); if (ret_val != 0) return ret_val; return netlbl_unlhsh_add(&init_net, NULL, addr, mask, addr_len, secid, &audit_info); } /** * netlbl_unlabel_staticremove - Handle a STATICREMOVE message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated STATICREMOVE message and remove the specified * unlabeled connection entry. Returns zero on success, negative values on * failure. * */ static int netlbl_unlabel_staticremove(struct sk_buff *skb, struct genl_info *info) { int ret_val; char *dev_name; void *addr; void *mask; u32 addr_len; struct netlbl_audit audit_info; /* See the note in netlbl_unlabel_staticadd() about not allowing both * IPv4 and IPv6 in the same entry. */ if (!info->attrs[NLBL_UNLABEL_A_IFACE] || !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] || !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^ (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] || !info->attrs[NLBL_UNLABEL_A_IPV6MASK]))) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len); if (ret_val != 0) return ret_val; dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]); return netlbl_unlhsh_remove(&init_net, dev_name, addr, mask, addr_len, &audit_info); } /** * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated STATICREMOVEDEF message and remove the default * unlabeled connection entry. Returns zero on success, negative values on * failure. * */ static int netlbl_unlabel_staticremovedef(struct sk_buff *skb, struct genl_info *info) { int ret_val; void *addr; void *mask; u32 addr_len; struct netlbl_audit audit_info; /* See the note in netlbl_unlabel_staticadd() about not allowing both * IPv4 and IPv6 in the same entry. */ if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] || !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^ (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] || !info->attrs[NLBL_UNLABEL_A_IPV6MASK]))) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len); if (ret_val != 0) return ret_val; return netlbl_unlhsh_remove(&init_net, NULL, addr, mask, addr_len, &audit_info); } /** * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF] * @cmd: command/message * @iface: the interface entry * @addr4: the IPv4 address entry * @addr6: the IPv6 address entry * @arg: the netlbl_unlhsh_walk_arg structure * * Description: * This function is designed to be used to generate a response for a * STATICLIST or STATICLISTDEF message. When called either @addr4 or @addr6 * can be specified, not both, the other unspecified entry should be set to * NULL by the caller. Returns the size of the message on success, negative * values on failure. * */ static int netlbl_unlabel_staticlist_gen(u32 cmd, const struct netlbl_unlhsh_iface *iface, const struct netlbl_unlhsh_addr4 *addr4, const struct netlbl_unlhsh_addr6 *addr6, void *arg) { int ret_val = -ENOMEM; struct netlbl_unlhsh_walk_arg *cb_arg = arg; struct net_device *dev; void *data; u32 secid; char *secctx; u32 secctx_len; data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid, cb_arg->seq, &netlbl_unlabel_gnl_family, NLM_F_MULTI, cmd); if (data == NULL) goto list_cb_failure; if (iface->ifindex > 0) { dev = dev_get_by_index(&init_net, iface->ifindex); if (!dev) { ret_val = -ENODEV; goto list_cb_failure; } ret_val = nla_put_string(cb_arg->skb, NLBL_UNLABEL_A_IFACE, dev->name); dev_put(dev); if (ret_val != 0) goto list_cb_failure; } if (addr4) { struct in_addr addr_struct; addr_struct.s_addr = addr4->list.addr; ret_val = nla_put_in_addr(cb_arg->skb, NLBL_UNLABEL_A_IPV4ADDR, addr_struct.s_addr); if (ret_val != 0) goto list_cb_failure; addr_struct.s_addr = addr4->list.mask; ret_val = nla_put_in_addr(cb_arg->skb, NLBL_UNLABEL_A_IPV4MASK, addr_struct.s_addr); if (ret_val != 0) goto list_cb_failure; secid = addr4->secid; } else { ret_val = nla_put_in6_addr(cb_arg->skb, NLBL_UNLABEL_A_IPV6ADDR, &addr6->list.addr); if (ret_val != 0) goto list_cb_failure; ret_val = nla_put_in6_addr(cb_arg->skb, NLBL_UNLABEL_A_IPV6MASK, &addr6->list.mask); if (ret_val != 0) goto list_cb_failure; secid = addr6->secid; } ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len); if (ret_val != 0) goto list_cb_failure; ret_val = nla_put(cb_arg->skb, NLBL_UNLABEL_A_SECCTX, secctx_len, secctx); security_release_secctx(secctx, secctx_len); if (ret_val != 0) goto list_cb_failure; cb_arg->seq++; genlmsg_end(cb_arg->skb, data); return 0; list_cb_failure: genlmsg_cancel(cb_arg->skb, data); return ret_val; } /** * netlbl_unlabel_staticlist - Handle a STATICLIST message * @skb: the NETLINK buffer * @cb: the NETLINK callback * * Description: * Process a user generated STATICLIST message and dump the unlabeled * connection hash table in a form suitable for use in a kernel generated * STATICLIST message. Returns the length of @skb. * */ static int netlbl_unlabel_staticlist(struct sk_buff *skb, struct netlink_callback *cb) { struct netlbl_unlhsh_walk_arg cb_arg; u32 skip_bkt = cb->args[0]; u32 skip_chain = cb->args[1]; u32 skip_addr4 = cb->args[2]; u32 iter_bkt, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0; struct netlbl_unlhsh_iface *iface; struct list_head *iter_list; struct netlbl_af4list *addr4; #if IS_ENABLED(CONFIG_IPV6) u32 skip_addr6 = cb->args[3]; struct netlbl_af6list *addr6; #endif cb_arg.nl_cb = cb; cb_arg.skb = skb; cb_arg.seq = cb->nlh->nlmsg_seq; rcu_read_lock(); for (iter_bkt = skip_bkt; iter_bkt < rcu_dereference(netlbl_unlhsh)->size; iter_bkt++) { iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt]; list_for_each_entry_rcu(iface, iter_list, list) { if (!iface->valid || iter_chain++ < skip_chain) continue; netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) { if (iter_addr4++ < skip_addr4) continue; if (netlbl_unlabel_staticlist_gen( NLBL_UNLABEL_C_STATICLIST, iface, netlbl_unlhsh_addr4_entry(addr4), NULL, &cb_arg) < 0) { iter_addr4--; iter_chain--; goto unlabel_staticlist_return; } } iter_addr4 = 0; skip_addr4 = 0; #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) { if (iter_addr6++ < skip_addr6) continue; if (netlbl_unlabel_staticlist_gen( NLBL_UNLABEL_C_STATICLIST, iface, NULL, netlbl_unlhsh_addr6_entry(addr6), &cb_arg) < 0) { iter_addr6--; iter_chain--; goto unlabel_staticlist_return; } } iter_addr6 = 0; skip_addr6 = 0; #endif /* IPv6 */ } iter_chain = 0; skip_chain = 0; } unlabel_staticlist_return: rcu_read_unlock(); cb->args[0] = iter_bkt; cb->args[1] = iter_chain; cb->args[2] = iter_addr4; cb->args[3] = iter_addr6; return skb->len; } /** * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message * @skb: the NETLINK buffer * @cb: the NETLINK callback * * Description: * Process a user generated STATICLISTDEF message and dump the default * unlabeled connection entry in a form suitable for use in a kernel generated * STATICLISTDEF message. Returns the length of @skb. * */ static int netlbl_unlabel_staticlistdef(struct sk_buff *skb, struct netlink_callback *cb) { struct netlbl_unlhsh_walk_arg cb_arg; struct netlbl_unlhsh_iface *iface; u32 iter_addr4 = 0, iter_addr6 = 0; struct netlbl_af4list *addr4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *addr6; #endif cb_arg.nl_cb = cb; cb_arg.skb = skb; cb_arg.seq = cb->nlh->nlmsg_seq; rcu_read_lock(); iface = rcu_dereference(netlbl_unlhsh_def); if (iface == NULL || !iface->valid) goto unlabel_staticlistdef_return; netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) { if (iter_addr4++ < cb->args[0]) continue; if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF, iface, netlbl_unlhsh_addr4_entry(addr4), NULL, &cb_arg) < 0) { iter_addr4--; goto unlabel_staticlistdef_return; } } #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) { if (iter_addr6++ < cb->args[1]) continue; if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF, iface, NULL, netlbl_unlhsh_addr6_entry(addr6), &cb_arg) < 0) { iter_addr6--; goto unlabel_staticlistdef_return; } } #endif /* IPv6 */ unlabel_staticlistdef_return: rcu_read_unlock(); cb->args[0] = iter_addr4; cb->args[1] = iter_addr6; return skb->len; } /* * NetLabel Generic NETLINK Command Definitions */ static const struct genl_small_ops netlbl_unlabel_genl_ops[] = { { .cmd = NLBL_UNLABEL_C_STATICADD, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_unlabel_staticadd, .dumpit = NULL, }, { .cmd = NLBL_UNLABEL_C_STATICREMOVE, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_unlabel_staticremove, .dumpit = NULL, }, { .cmd = NLBL_UNLABEL_C_STATICLIST, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = NULL, .dumpit = netlbl_unlabel_staticlist, }, { .cmd = NLBL_UNLABEL_C_STATICADDDEF, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_unlabel_staticadddef, .dumpit = NULL, }, { .cmd = NLBL_UNLABEL_C_STATICREMOVEDEF, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_unlabel_staticremovedef, .dumpit = NULL, }, { .cmd = NLBL_UNLABEL_C_STATICLISTDEF, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = NULL, .dumpit = netlbl_unlabel_staticlistdef, }, { .cmd = NLBL_UNLABEL_C_ACCEPT, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_unlabel_accept, .dumpit = NULL, }, { .cmd = NLBL_UNLABEL_C_LIST, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = netlbl_unlabel_list, .dumpit = NULL, }, }; static struct genl_family netlbl_unlabel_gnl_family __ro_after_init = { .hdrsize = 0, .name = NETLBL_NLTYPE_UNLABELED_NAME, .version = NETLBL_PROTO_VERSION, .maxattr = NLBL_UNLABEL_A_MAX, .policy = netlbl_unlabel_genl_policy, .module = THIS_MODULE, .small_ops = netlbl_unlabel_genl_ops, .n_small_ops = ARRAY_SIZE(netlbl_unlabel_genl_ops), .resv_start_op = NLBL_UNLABEL_C_STATICLISTDEF + 1, }; /* * NetLabel Generic NETLINK Protocol Functions */ /** * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component * * Description: * Register the unlabeled packet NetLabel component with the Generic NETLINK * mechanism. Returns zero on success, negative values on failure. * */ int __init netlbl_unlabel_genl_init(void) { return genl_register_family(&netlbl_unlabel_gnl_family); } /* * NetLabel KAPI Hooks */ static struct notifier_block netlbl_unlhsh_netdev_notifier = { .notifier_call = netlbl_unlhsh_netdev_handler, }; /** * netlbl_unlabel_init - Initialize the unlabeled connection hash table * @size: the number of bits to use for the hash buckets * * Description: * Initializes the unlabeled connection hash table and registers a network * device notification handler. This function should only be called by the * NetLabel subsystem itself during initialization. Returns zero on success, * non-zero values on error. * */ int __init netlbl_unlabel_init(u32 size) { u32 iter; struct netlbl_unlhsh_tbl *hsh_tbl; if (size == 0) return -EINVAL; hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL); if (hsh_tbl == NULL) return -ENOMEM; hsh_tbl->size = 1 << size; hsh_tbl->tbl = kcalloc(hsh_tbl->size, sizeof(struct list_head), GFP_KERNEL); if (hsh_tbl->tbl == NULL) { kfree(hsh_tbl); return -ENOMEM; } for (iter = 0; iter < hsh_tbl->size; iter++) INIT_LIST_HEAD(&hsh_tbl->tbl[iter]); spin_lock(&netlbl_unlhsh_lock); rcu_assign_pointer(netlbl_unlhsh, hsh_tbl); spin_unlock(&netlbl_unlhsh_lock); register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier); return 0; } /** * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet * @skb: the packet * @family: protocol family * @secattr: the security attributes * * Description: * Determine the security attributes, if any, for an unlabled packet and return * them in @secattr. Returns zero on success and negative values on failure. * */ int netlbl_unlabel_getattr(const struct sk_buff *skb, u16 family, struct netlbl_lsm_secattr *secattr) { struct netlbl_unlhsh_iface *iface; rcu_read_lock(); iface = netlbl_unlhsh_search_iface(skb->skb_iif); if (iface == NULL) iface = rcu_dereference(netlbl_unlhsh_def); if (iface == NULL || !iface->valid) goto unlabel_getattr_nolabel; #if IS_ENABLED(CONFIG_IPV6) /* When resolving a fallback label, check the sk_buff version as * it is possible (e.g. SCTP) to have family = PF_INET6 while * receiving ip_hdr(skb)->version = 4. */ if (family == PF_INET6 && ip_hdr(skb)->version == 4) family = PF_INET; #endif /* IPv6 */ switch (family) { case PF_INET: { struct iphdr *hdr4; struct netlbl_af4list *addr4; hdr4 = ip_hdr(skb); addr4 = netlbl_af4list_search(hdr4->saddr, &iface->addr4_list); if (addr4 == NULL) goto unlabel_getattr_nolabel; secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid; break; } #if IS_ENABLED(CONFIG_IPV6) case PF_INET6: { struct ipv6hdr *hdr6; struct netlbl_af6list *addr6; hdr6 = ipv6_hdr(skb); addr6 = netlbl_af6list_search(&hdr6->saddr, &iface->addr6_list); if (addr6 == NULL) goto unlabel_getattr_nolabel; secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid; break; } #endif /* IPv6 */ default: goto unlabel_getattr_nolabel; } rcu_read_unlock(); secattr->flags |= NETLBL_SECATTR_SECID; secattr->type = NETLBL_NLTYPE_UNLABELED; return 0; unlabel_getattr_nolabel: rcu_read_unlock(); if (netlabel_unlabel_acceptflg == 0) return -ENOMSG; secattr->type = NETLBL_NLTYPE_UNLABELED; return 0; } /** * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets * * Description: * Set the default NetLabel configuration to allow incoming unlabeled packets * and to send unlabeled network traffic by default. * */ int __init netlbl_unlabel_defconf(void) { int ret_val; struct netlbl_dom_map *entry; struct netlbl_audit audit_info; /* Only the kernel is allowed to call this function and the only time * it is called is at bootup before the audit subsystem is reporting * messages so don't worry to much about these values. */ security_current_getsecid_subj(&audit_info.secid); audit_info.loginuid = GLOBAL_ROOT_UID; audit_info.sessionid = 0; entry = kzalloc(sizeof(*entry), GFP_KERNEL); if (entry == NULL) return -ENOMEM; entry->family = AF_UNSPEC; entry->def.type = NETLBL_NLTYPE_UNLABELED; ret_val = netlbl_domhsh_add_default(entry, &audit_info); if (ret_val != 0) return ret_val; netlbl_unlabel_acceptflg_set(1, &audit_info); return 0; }
linux-master
net/netlabel/netlabel_unlabeled.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NetLabel Domain Hash Table * * This file manages the domain hash table that NetLabel uses to determine * which network labeling protocol to use for a given domain. The NetLabel * system manages static and dynamic label mappings for network protocols such * as CIPSO and RIPSO. * * Author: Paul Moore <[email protected]> */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 */ #include <linux/types.h> #include <linux/rculist.h> #include <linux/skbuff.h> #include <linux/spinlock.h> #include <linux/string.h> #include <linux/audit.h> #include <linux/slab.h> #include <net/netlabel.h> #include <net/cipso_ipv4.h> #include <net/calipso.h> #include <asm/bug.h> #include "netlabel_mgmt.h" #include "netlabel_addrlist.h" #include "netlabel_calipso.h" #include "netlabel_domainhash.h" #include "netlabel_user.h" struct netlbl_domhsh_tbl { struct list_head *tbl; u32 size; }; /* Domain hash table */ /* updates should be so rare that having one spinlock for the entire hash table * should be okay */ static DEFINE_SPINLOCK(netlbl_domhsh_lock); #define netlbl_domhsh_rcu_deref(p) \ rcu_dereference_check(p, lockdep_is_held(&netlbl_domhsh_lock)) static struct netlbl_domhsh_tbl __rcu *netlbl_domhsh; static struct netlbl_dom_map __rcu *netlbl_domhsh_def_ipv4; static struct netlbl_dom_map __rcu *netlbl_domhsh_def_ipv6; /* * Domain Hash Table Helper Functions */ /** * netlbl_domhsh_free_entry - Frees a domain hash table entry * @entry: the entry's RCU field * * Description: * This function is designed to be used as a callback to the call_rcu() * function so that the memory allocated to a hash table entry can be released * safely. * */ static void netlbl_domhsh_free_entry(struct rcu_head *entry) { struct netlbl_dom_map *ptr; struct netlbl_af4list *iter4; struct netlbl_af4list *tmp4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *iter6; struct netlbl_af6list *tmp6; #endif /* IPv6 */ ptr = container_of(entry, struct netlbl_dom_map, rcu); if (ptr->def.type == NETLBL_NLTYPE_ADDRSELECT) { netlbl_af4list_foreach_safe(iter4, tmp4, &ptr->def.addrsel->list4) { netlbl_af4list_remove_entry(iter4); kfree(netlbl_domhsh_addr4_entry(iter4)); } #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_safe(iter6, tmp6, &ptr->def.addrsel->list6) { netlbl_af6list_remove_entry(iter6); kfree(netlbl_domhsh_addr6_entry(iter6)); } #endif /* IPv6 */ kfree(ptr->def.addrsel); } kfree(ptr->domain); kfree(ptr); } /** * netlbl_domhsh_hash - Hashing function for the domain hash table * @key: the domain name to hash * * Description: * This is the hashing function for the domain hash table, it returns the * correct bucket number for the domain. The caller is responsible for * ensuring that the hash table is protected with either a RCU read lock or the * hash table lock. * */ static u32 netlbl_domhsh_hash(const char *key) { u32 iter; u32 val; u32 len; /* This is taken (with slight modification) from * security/selinux/ss/symtab.c:symhash() */ for (iter = 0, val = 0, len = strlen(key); iter < len; iter++) val = (val << 4 | (val >> (8 * sizeof(u32) - 4))) ^ key[iter]; return val & (netlbl_domhsh_rcu_deref(netlbl_domhsh)->size - 1); } static bool netlbl_family_match(u16 f1, u16 f2) { return (f1 == f2) || (f1 == AF_UNSPEC) || (f2 == AF_UNSPEC); } /** * netlbl_domhsh_search - Search for a domain entry * @domain: the domain * @family: the address family * * Description: * Searches the domain hash table and returns a pointer to the hash table * entry if found, otherwise NULL is returned. @family may be %AF_UNSPEC * which matches any address family entries. The caller is responsible for * ensuring that the hash table is protected with either a RCU read lock or the * hash table lock. * */ static struct netlbl_dom_map *netlbl_domhsh_search(const char *domain, u16 family) { u32 bkt; struct list_head *bkt_list; struct netlbl_dom_map *iter; if (domain != NULL) { bkt = netlbl_domhsh_hash(domain); bkt_list = &netlbl_domhsh_rcu_deref(netlbl_domhsh)->tbl[bkt]; list_for_each_entry_rcu(iter, bkt_list, list, lockdep_is_held(&netlbl_domhsh_lock)) if (iter->valid && netlbl_family_match(iter->family, family) && strcmp(iter->domain, domain) == 0) return iter; } return NULL; } /** * netlbl_domhsh_search_def - Search for a domain entry * @domain: the domain * @family: the address family * * Description: * Searches the domain hash table and returns a pointer to the hash table * entry if an exact match is found, if an exact match is not present in the * hash table then the default entry is returned if valid otherwise NULL is * returned. @family may be %AF_UNSPEC which matches any address family * entries. The caller is responsible ensuring that the hash table is * protected with either a RCU read lock or the hash table lock. * */ static struct netlbl_dom_map *netlbl_domhsh_search_def(const char *domain, u16 family) { struct netlbl_dom_map *entry; entry = netlbl_domhsh_search(domain, family); if (entry != NULL) return entry; if (family == AF_INET || family == AF_UNSPEC) { entry = netlbl_domhsh_rcu_deref(netlbl_domhsh_def_ipv4); if (entry != NULL && entry->valid) return entry; } if (family == AF_INET6 || family == AF_UNSPEC) { entry = netlbl_domhsh_rcu_deref(netlbl_domhsh_def_ipv6); if (entry != NULL && entry->valid) return entry; } return NULL; } /** * netlbl_domhsh_audit_add - Generate an audit entry for an add event * @entry: the entry being added * @addr4: the IPv4 address information * @addr6: the IPv6 address information * @result: the result code * @audit_info: NetLabel audit information * * Description: * Generate an audit record for adding a new NetLabel/LSM mapping entry with * the given information. Caller is responsible for holding the necessary * locks. * */ static void netlbl_domhsh_audit_add(struct netlbl_dom_map *entry, struct netlbl_af4list *addr4, struct netlbl_af6list *addr6, int result, struct netlbl_audit *audit_info) { struct audit_buffer *audit_buf; struct cipso_v4_doi *cipsov4 = NULL; struct calipso_doi *calipso = NULL; u32 type; audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_ADD, audit_info); if (audit_buf != NULL) { audit_log_format(audit_buf, " nlbl_domain=%s", entry->domain ? entry->domain : "(default)"); if (addr4 != NULL) { struct netlbl_domaddr4_map *map4; map4 = netlbl_domhsh_addr4_entry(addr4); type = map4->def.type; cipsov4 = map4->def.cipso; netlbl_af4list_audit_addr(audit_buf, 0, NULL, addr4->addr, addr4->mask); #if IS_ENABLED(CONFIG_IPV6) } else if (addr6 != NULL) { struct netlbl_domaddr6_map *map6; map6 = netlbl_domhsh_addr6_entry(addr6); type = map6->def.type; calipso = map6->def.calipso; netlbl_af6list_audit_addr(audit_buf, 0, NULL, &addr6->addr, &addr6->mask); #endif /* IPv6 */ } else { type = entry->def.type; cipsov4 = entry->def.cipso; calipso = entry->def.calipso; } switch (type) { case NETLBL_NLTYPE_UNLABELED: audit_log_format(audit_buf, " nlbl_protocol=unlbl"); break; case NETLBL_NLTYPE_CIPSOV4: BUG_ON(cipsov4 == NULL); audit_log_format(audit_buf, " nlbl_protocol=cipsov4 cipso_doi=%u", cipsov4->doi); break; case NETLBL_NLTYPE_CALIPSO: BUG_ON(calipso == NULL); audit_log_format(audit_buf, " nlbl_protocol=calipso calipso_doi=%u", calipso->doi); break; } audit_log_format(audit_buf, " res=%u", result == 0 ? 1 : 0); audit_log_end(audit_buf); } } /** * netlbl_domhsh_validate - Validate a new domain mapping entry * @entry: the entry to validate * * This function validates the new domain mapping entry to ensure that it is * a valid entry. Returns zero on success, negative values on failure. * */ static int netlbl_domhsh_validate(const struct netlbl_dom_map *entry) { struct netlbl_af4list *iter4; struct netlbl_domaddr4_map *map4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *iter6; struct netlbl_domaddr6_map *map6; #endif /* IPv6 */ if (entry == NULL) return -EINVAL; if (entry->family != AF_INET && entry->family != AF_INET6 && (entry->family != AF_UNSPEC || entry->def.type != NETLBL_NLTYPE_UNLABELED)) return -EINVAL; switch (entry->def.type) { case NETLBL_NLTYPE_UNLABELED: if (entry->def.cipso != NULL || entry->def.calipso != NULL || entry->def.addrsel != NULL) return -EINVAL; break; case NETLBL_NLTYPE_CIPSOV4: if (entry->family != AF_INET || entry->def.cipso == NULL) return -EINVAL; break; case NETLBL_NLTYPE_CALIPSO: if (entry->family != AF_INET6 || entry->def.calipso == NULL) return -EINVAL; break; case NETLBL_NLTYPE_ADDRSELECT: netlbl_af4list_foreach(iter4, &entry->def.addrsel->list4) { map4 = netlbl_domhsh_addr4_entry(iter4); switch (map4->def.type) { case NETLBL_NLTYPE_UNLABELED: if (map4->def.cipso != NULL) return -EINVAL; break; case NETLBL_NLTYPE_CIPSOV4: if (map4->def.cipso == NULL) return -EINVAL; break; default: return -EINVAL; } } #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach(iter6, &entry->def.addrsel->list6) { map6 = netlbl_domhsh_addr6_entry(iter6); switch (map6->def.type) { case NETLBL_NLTYPE_UNLABELED: if (map6->def.calipso != NULL) return -EINVAL; break; case NETLBL_NLTYPE_CALIPSO: if (map6->def.calipso == NULL) return -EINVAL; break; default: return -EINVAL; } } #endif /* IPv6 */ break; default: return -EINVAL; } return 0; } /* * Domain Hash Table Functions */ /** * netlbl_domhsh_init - Init for the domain hash * @size: the number of bits to use for the hash buckets * * Description: * Initializes the domain hash table, should be called only by * netlbl_user_init() during initialization. Returns zero on success, non-zero * values on error. * */ int __init netlbl_domhsh_init(u32 size) { u32 iter; struct netlbl_domhsh_tbl *hsh_tbl; if (size == 0) return -EINVAL; hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL); if (hsh_tbl == NULL) return -ENOMEM; hsh_tbl->size = 1 << size; hsh_tbl->tbl = kcalloc(hsh_tbl->size, sizeof(struct list_head), GFP_KERNEL); if (hsh_tbl->tbl == NULL) { kfree(hsh_tbl); return -ENOMEM; } for (iter = 0; iter < hsh_tbl->size; iter++) INIT_LIST_HEAD(&hsh_tbl->tbl[iter]); spin_lock(&netlbl_domhsh_lock); rcu_assign_pointer(netlbl_domhsh, hsh_tbl); spin_unlock(&netlbl_domhsh_lock); return 0; } /** * netlbl_domhsh_add - Adds a entry to the domain hash table * @entry: the entry to add * @audit_info: NetLabel audit information * * Description: * Adds a new entry to the domain hash table and handles any updates to the * lower level protocol handler (i.e. CIPSO). @entry->family may be set to * %AF_UNSPEC which will add an entry that matches all address families. This * is only useful for the unlabelled type and will only succeed if there is no * existing entry for any address family with the same domain. Returns zero * on success, negative on failure. * */ int netlbl_domhsh_add(struct netlbl_dom_map *entry, struct netlbl_audit *audit_info) { int ret_val = 0; struct netlbl_dom_map *entry_old, *entry_b; struct netlbl_af4list *iter4; struct netlbl_af4list *tmp4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *iter6; struct netlbl_af6list *tmp6; #endif /* IPv6 */ ret_val = netlbl_domhsh_validate(entry); if (ret_val != 0) return ret_val; /* XXX - we can remove this RCU read lock as the spinlock protects the * entire function, but before we do we need to fixup the * netlbl_af[4,6]list RCU functions to do "the right thing" with * respect to rcu_dereference() when only a spinlock is held. */ rcu_read_lock(); spin_lock(&netlbl_domhsh_lock); if (entry->domain != NULL) entry_old = netlbl_domhsh_search(entry->domain, entry->family); else entry_old = netlbl_domhsh_search_def(entry->domain, entry->family); if (entry_old == NULL) { entry->valid = 1; if (entry->domain != NULL) { u32 bkt = netlbl_domhsh_hash(entry->domain); list_add_tail_rcu(&entry->list, &rcu_dereference(netlbl_domhsh)->tbl[bkt]); } else { INIT_LIST_HEAD(&entry->list); switch (entry->family) { case AF_INET: rcu_assign_pointer(netlbl_domhsh_def_ipv4, entry); break; case AF_INET6: rcu_assign_pointer(netlbl_domhsh_def_ipv6, entry); break; case AF_UNSPEC: if (entry->def.type != NETLBL_NLTYPE_UNLABELED) { ret_val = -EINVAL; goto add_return; } entry_b = kzalloc(sizeof(*entry_b), GFP_ATOMIC); if (entry_b == NULL) { ret_val = -ENOMEM; goto add_return; } entry_b->family = AF_INET6; entry_b->def.type = NETLBL_NLTYPE_UNLABELED; entry_b->valid = 1; entry->family = AF_INET; rcu_assign_pointer(netlbl_domhsh_def_ipv4, entry); rcu_assign_pointer(netlbl_domhsh_def_ipv6, entry_b); break; default: /* Already checked in * netlbl_domhsh_validate(). */ ret_val = -EINVAL; goto add_return; } } if (entry->def.type == NETLBL_NLTYPE_ADDRSELECT) { netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) netlbl_domhsh_audit_add(entry, iter4, NULL, ret_val, audit_info); #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) netlbl_domhsh_audit_add(entry, NULL, iter6, ret_val, audit_info); #endif /* IPv6 */ } else netlbl_domhsh_audit_add(entry, NULL, NULL, ret_val, audit_info); } else if (entry_old->def.type == NETLBL_NLTYPE_ADDRSELECT && entry->def.type == NETLBL_NLTYPE_ADDRSELECT) { struct list_head *old_list4; struct list_head *old_list6; old_list4 = &entry_old->def.addrsel->list4; old_list6 = &entry_old->def.addrsel->list6; /* we only allow the addition of address selectors if all of * the selectors do not exist in the existing domain map */ netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) if (netlbl_af4list_search_exact(iter4->addr, iter4->mask, old_list4)) { ret_val = -EEXIST; goto add_return; } #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) if (netlbl_af6list_search_exact(&iter6->addr, &iter6->mask, old_list6)) { ret_val = -EEXIST; goto add_return; } #endif /* IPv6 */ netlbl_af4list_foreach_safe(iter4, tmp4, &entry->def.addrsel->list4) { netlbl_af4list_remove_entry(iter4); iter4->valid = 1; ret_val = netlbl_af4list_add(iter4, old_list4); netlbl_domhsh_audit_add(entry_old, iter4, NULL, ret_val, audit_info); if (ret_val != 0) goto add_return; } #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_safe(iter6, tmp6, &entry->def.addrsel->list6) { netlbl_af6list_remove_entry(iter6); iter6->valid = 1; ret_val = netlbl_af6list_add(iter6, old_list6); netlbl_domhsh_audit_add(entry_old, NULL, iter6, ret_val, audit_info); if (ret_val != 0) goto add_return; } #endif /* IPv6 */ /* cleanup the new entry since we've moved everything over */ netlbl_domhsh_free_entry(&entry->rcu); } else ret_val = -EINVAL; add_return: spin_unlock(&netlbl_domhsh_lock); rcu_read_unlock(); return ret_val; } /** * netlbl_domhsh_add_default - Adds the default entry to the domain hash table * @entry: the entry to add * @audit_info: NetLabel audit information * * Description: * Adds a new default entry to the domain hash table and handles any updates * to the lower level protocol handler (i.e. CIPSO). Returns zero on success, * negative on failure. * */ int netlbl_domhsh_add_default(struct netlbl_dom_map *entry, struct netlbl_audit *audit_info) { return netlbl_domhsh_add(entry, audit_info); } /** * netlbl_domhsh_remove_entry - Removes a given entry from the domain table * @entry: the entry to remove * @audit_info: NetLabel audit information * * Description: * Removes an entry from the domain hash table and handles any updates to the * lower level protocol handler (i.e. CIPSO). Caller is responsible for * ensuring that the RCU read lock is held. Returns zero on success, negative * on failure. * */ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry, struct netlbl_audit *audit_info) { int ret_val = 0; struct audit_buffer *audit_buf; struct netlbl_af4list *iter4; struct netlbl_domaddr4_map *map4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *iter6; struct netlbl_domaddr6_map *map6; #endif /* IPv6 */ if (entry == NULL) return -ENOENT; spin_lock(&netlbl_domhsh_lock); if (entry->valid) { entry->valid = 0; if (entry == rcu_dereference(netlbl_domhsh_def_ipv4)) RCU_INIT_POINTER(netlbl_domhsh_def_ipv4, NULL); else if (entry == rcu_dereference(netlbl_domhsh_def_ipv6)) RCU_INIT_POINTER(netlbl_domhsh_def_ipv6, NULL); else list_del_rcu(&entry->list); } else ret_val = -ENOENT; spin_unlock(&netlbl_domhsh_lock); if (ret_val) return ret_val; audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info); if (audit_buf != NULL) { audit_log_format(audit_buf, " nlbl_domain=%s res=1", entry->domain ? entry->domain : "(default)"); audit_log_end(audit_buf); } switch (entry->def.type) { case NETLBL_NLTYPE_ADDRSELECT: netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) { map4 = netlbl_domhsh_addr4_entry(iter4); cipso_v4_doi_putdef(map4->def.cipso); } #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) { map6 = netlbl_domhsh_addr6_entry(iter6); calipso_doi_putdef(map6->def.calipso); } #endif /* IPv6 */ break; case NETLBL_NLTYPE_CIPSOV4: cipso_v4_doi_putdef(entry->def.cipso); break; #if IS_ENABLED(CONFIG_IPV6) case NETLBL_NLTYPE_CALIPSO: calipso_doi_putdef(entry->def.calipso); break; #endif /* IPv6 */ } call_rcu(&entry->rcu, netlbl_domhsh_free_entry); return ret_val; } /** * netlbl_domhsh_remove_af4 - Removes an address selector entry * @domain: the domain * @addr: IPv4 address * @mask: IPv4 address mask * @audit_info: NetLabel audit information * * Description: * Removes an individual address selector from a domain mapping and potentially * the entire mapping if it is empty. Returns zero on success, negative values * on failure. * */ int netlbl_domhsh_remove_af4(const char *domain, const struct in_addr *addr, const struct in_addr *mask, struct netlbl_audit *audit_info) { struct netlbl_dom_map *entry_map; struct netlbl_af4list *entry_addr; struct netlbl_af4list *iter4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *iter6; #endif /* IPv6 */ struct netlbl_domaddr4_map *entry; rcu_read_lock(); if (domain) entry_map = netlbl_domhsh_search(domain, AF_INET); else entry_map = netlbl_domhsh_search_def(domain, AF_INET); if (entry_map == NULL || entry_map->def.type != NETLBL_NLTYPE_ADDRSELECT) goto remove_af4_failure; spin_lock(&netlbl_domhsh_lock); entry_addr = netlbl_af4list_remove(addr->s_addr, mask->s_addr, &entry_map->def.addrsel->list4); spin_unlock(&netlbl_domhsh_lock); if (entry_addr == NULL) goto remove_af4_failure; netlbl_af4list_foreach_rcu(iter4, &entry_map->def.addrsel->list4) goto remove_af4_single_addr; #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_rcu(iter6, &entry_map->def.addrsel->list6) goto remove_af4_single_addr; #endif /* IPv6 */ /* the domain mapping is empty so remove it from the mapping table */ netlbl_domhsh_remove_entry(entry_map, audit_info); remove_af4_single_addr: rcu_read_unlock(); /* yick, we can't use call_rcu here because we don't have a rcu head * pointer but hopefully this should be a rare case so the pause * shouldn't be a problem */ synchronize_rcu(); entry = netlbl_domhsh_addr4_entry(entry_addr); cipso_v4_doi_putdef(entry->def.cipso); kfree(entry); return 0; remove_af4_failure: rcu_read_unlock(); return -ENOENT; } #if IS_ENABLED(CONFIG_IPV6) /** * netlbl_domhsh_remove_af6 - Removes an address selector entry * @domain: the domain * @addr: IPv6 address * @mask: IPv6 address mask * @audit_info: NetLabel audit information * * Description: * Removes an individual address selector from a domain mapping and potentially * the entire mapping if it is empty. Returns zero on success, negative values * on failure. * */ int netlbl_domhsh_remove_af6(const char *domain, const struct in6_addr *addr, const struct in6_addr *mask, struct netlbl_audit *audit_info) { struct netlbl_dom_map *entry_map; struct netlbl_af6list *entry_addr; struct netlbl_af4list *iter4; struct netlbl_af6list *iter6; struct netlbl_domaddr6_map *entry; rcu_read_lock(); if (domain) entry_map = netlbl_domhsh_search(domain, AF_INET6); else entry_map = netlbl_domhsh_search_def(domain, AF_INET6); if (entry_map == NULL || entry_map->def.type != NETLBL_NLTYPE_ADDRSELECT) goto remove_af6_failure; spin_lock(&netlbl_domhsh_lock); entry_addr = netlbl_af6list_remove(addr, mask, &entry_map->def.addrsel->list6); spin_unlock(&netlbl_domhsh_lock); if (entry_addr == NULL) goto remove_af6_failure; netlbl_af4list_foreach_rcu(iter4, &entry_map->def.addrsel->list4) goto remove_af6_single_addr; netlbl_af6list_foreach_rcu(iter6, &entry_map->def.addrsel->list6) goto remove_af6_single_addr; /* the domain mapping is empty so remove it from the mapping table */ netlbl_domhsh_remove_entry(entry_map, audit_info); remove_af6_single_addr: rcu_read_unlock(); /* yick, we can't use call_rcu here because we don't have a rcu head * pointer but hopefully this should be a rare case so the pause * shouldn't be a problem */ synchronize_rcu(); entry = netlbl_domhsh_addr6_entry(entry_addr); calipso_doi_putdef(entry->def.calipso); kfree(entry); return 0; remove_af6_failure: rcu_read_unlock(); return -ENOENT; } #endif /* IPv6 */ /** * netlbl_domhsh_remove - Removes an entry from the domain hash table * @domain: the domain to remove * @family: address family * @audit_info: NetLabel audit information * * Description: * Removes an entry from the domain hash table and handles any updates to the * lower level protocol handler (i.e. CIPSO). @family may be %AF_UNSPEC which * removes all address family entries. Returns zero on success, negative on * failure. * */ int netlbl_domhsh_remove(const char *domain, u16 family, struct netlbl_audit *audit_info) { int ret_val = -EINVAL; struct netlbl_dom_map *entry; rcu_read_lock(); if (family == AF_INET || family == AF_UNSPEC) { if (domain) entry = netlbl_domhsh_search(domain, AF_INET); else entry = netlbl_domhsh_search_def(domain, AF_INET); ret_val = netlbl_domhsh_remove_entry(entry, audit_info); if (ret_val && ret_val != -ENOENT) goto done; } if (family == AF_INET6 || family == AF_UNSPEC) { int ret_val2; if (domain) entry = netlbl_domhsh_search(domain, AF_INET6); else entry = netlbl_domhsh_search_def(domain, AF_INET6); ret_val2 = netlbl_domhsh_remove_entry(entry, audit_info); if (ret_val2 != -ENOENT) ret_val = ret_val2; } done: rcu_read_unlock(); return ret_val; } /** * netlbl_domhsh_remove_default - Removes the default entry from the table * @family: address family * @audit_info: NetLabel audit information * * Description: * Removes/resets the default entry corresponding to @family from the domain * hash table and handles any updates to the lower level protocol handler * (i.e. CIPSO). @family may be %AF_UNSPEC which removes all address family * entries. Returns zero on success, negative on failure. * */ int netlbl_domhsh_remove_default(u16 family, struct netlbl_audit *audit_info) { return netlbl_domhsh_remove(NULL, family, audit_info); } /** * netlbl_domhsh_getentry - Get an entry from the domain hash table * @domain: the domain name to search for * @family: address family * * Description: * Look through the domain hash table searching for an entry to match @domain, * with address family @family, return a pointer to a copy of the entry or * NULL. The caller is responsible for ensuring that rcu_read_[un]lock() is * called. * */ struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain, u16 family) { if (family == AF_UNSPEC) return NULL; return netlbl_domhsh_search_def(domain, family); } /** * netlbl_domhsh_getentry_af4 - Get an entry from the domain hash table * @domain: the domain name to search for * @addr: the IP address to search for * * Description: * Look through the domain hash table searching for an entry to match @domain * and @addr, return a pointer to a copy of the entry or NULL. The caller is * responsible for ensuring that rcu_read_[un]lock() is called. * */ struct netlbl_dommap_def *netlbl_domhsh_getentry_af4(const char *domain, __be32 addr) { struct netlbl_dom_map *dom_iter; struct netlbl_af4list *addr_iter; dom_iter = netlbl_domhsh_search_def(domain, AF_INET); if (dom_iter == NULL) return NULL; if (dom_iter->def.type != NETLBL_NLTYPE_ADDRSELECT) return &dom_iter->def; addr_iter = netlbl_af4list_search(addr, &dom_iter->def.addrsel->list4); if (addr_iter == NULL) return NULL; return &(netlbl_domhsh_addr4_entry(addr_iter)->def); } #if IS_ENABLED(CONFIG_IPV6) /** * netlbl_domhsh_getentry_af6 - Get an entry from the domain hash table * @domain: the domain name to search for * @addr: the IP address to search for * * Description: * Look through the domain hash table searching for an entry to match @domain * and @addr, return a pointer to a copy of the entry or NULL. The caller is * responsible for ensuring that rcu_read_[un]lock() is called. * */ struct netlbl_dommap_def *netlbl_domhsh_getentry_af6(const char *domain, const struct in6_addr *addr) { struct netlbl_dom_map *dom_iter; struct netlbl_af6list *addr_iter; dom_iter = netlbl_domhsh_search_def(domain, AF_INET6); if (dom_iter == NULL) return NULL; if (dom_iter->def.type != NETLBL_NLTYPE_ADDRSELECT) return &dom_iter->def; addr_iter = netlbl_af6list_search(addr, &dom_iter->def.addrsel->list6); if (addr_iter == NULL) return NULL; return &(netlbl_domhsh_addr6_entry(addr_iter)->def); } #endif /* IPv6 */ /** * netlbl_domhsh_walk - Iterate through the domain mapping hash table * @skip_bkt: the number of buckets to skip at the start * @skip_chain: the number of entries to skip in the first iterated bucket * @callback: callback for each entry * @cb_arg: argument for the callback function * * Description: * Iterate over the domain mapping hash table, skipping the first @skip_bkt * buckets and @skip_chain entries. For each entry in the table call * @callback, if @callback returns a negative value stop 'walking' through the * table and return. Updates the values in @skip_bkt and @skip_chain on * return. Returns zero on success, negative values on failure. * */ int netlbl_domhsh_walk(u32 *skip_bkt, u32 *skip_chain, int (*callback) (struct netlbl_dom_map *entry, void *arg), void *cb_arg) { int ret_val = -ENOENT; u32 iter_bkt; struct list_head *iter_list; struct netlbl_dom_map *iter_entry; u32 chain_cnt = 0; rcu_read_lock(); for (iter_bkt = *skip_bkt; iter_bkt < rcu_dereference(netlbl_domhsh)->size; iter_bkt++, chain_cnt = 0) { iter_list = &rcu_dereference(netlbl_domhsh)->tbl[iter_bkt]; list_for_each_entry_rcu(iter_entry, iter_list, list) if (iter_entry->valid) { if (chain_cnt++ < *skip_chain) continue; ret_val = callback(iter_entry, cb_arg); if (ret_val < 0) { chain_cnt--; goto walk_return; } } } walk_return: rcu_read_unlock(); *skip_bkt = iter_bkt; *skip_chain = chain_cnt; return ret_val; }
linux-master
net/netlabel/netlabel_domainhash.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NetLabel Kernel API * * This file defines the kernel API for the NetLabel system. The NetLabel * system manages static and dynamic label mappings for network protocols such * as CIPSO and RIPSO. * * Author: Paul Moore <[email protected]> */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 */ #include <linux/init.h> #include <linux/types.h> #include <linux/slab.h> #include <linux/audit.h> #include <linux/in.h> #include <linux/in6.h> #include <net/ip.h> #include <net/ipv6.h> #include <net/netlabel.h> #include <net/cipso_ipv4.h> #include <net/calipso.h> #include <asm/bug.h> #include <linux/atomic.h> #include "netlabel_domainhash.h" #include "netlabel_unlabeled.h" #include "netlabel_cipso_v4.h" #include "netlabel_calipso.h" #include "netlabel_user.h" #include "netlabel_mgmt.h" #include "netlabel_addrlist.h" /* * Configuration Functions */ /** * netlbl_cfg_map_del - Remove a NetLabel/LSM domain mapping * @domain: the domain mapping to remove * @family: address family * @addr: IP address * @mask: IP address mask * @audit_info: NetLabel audit information * * Description: * Removes a NetLabel/LSM domain mapping. A @domain value of NULL causes the * default domain mapping to be removed. Returns zero on success, negative * values on failure. * */ int netlbl_cfg_map_del(const char *domain, u16 family, const void *addr, const void *mask, struct netlbl_audit *audit_info) { if (addr == NULL && mask == NULL) { return netlbl_domhsh_remove(domain, family, audit_info); } else if (addr != NULL && mask != NULL) { switch (family) { case AF_INET: return netlbl_domhsh_remove_af4(domain, addr, mask, audit_info); #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: return netlbl_domhsh_remove_af6(domain, addr, mask, audit_info); #endif /* IPv6 */ default: return -EPFNOSUPPORT; } } else return -EINVAL; } /** * netlbl_cfg_unlbl_map_add - Add a new unlabeled mapping * @domain: the domain mapping to add * @family: address family * @addr: IP address * @mask: IP address mask * @audit_info: NetLabel audit information * * Description: * Adds a new unlabeled NetLabel/LSM domain mapping. A @domain value of NULL * causes a new default domain mapping to be added. Returns zero on success, * negative values on failure. * */ int netlbl_cfg_unlbl_map_add(const char *domain, u16 family, const void *addr, const void *mask, struct netlbl_audit *audit_info) { int ret_val = -ENOMEM; struct netlbl_dom_map *entry; struct netlbl_domaddr_map *addrmap = NULL; struct netlbl_domaddr4_map *map4 = NULL; struct netlbl_domaddr6_map *map6 = NULL; entry = kzalloc(sizeof(*entry), GFP_ATOMIC); if (entry == NULL) return -ENOMEM; if (domain != NULL) { entry->domain = kstrdup(domain, GFP_ATOMIC); if (entry->domain == NULL) goto cfg_unlbl_map_add_failure; } entry->family = family; if (addr == NULL && mask == NULL) entry->def.type = NETLBL_NLTYPE_UNLABELED; else if (addr != NULL && mask != NULL) { addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC); if (addrmap == NULL) goto cfg_unlbl_map_add_failure; INIT_LIST_HEAD(&addrmap->list4); INIT_LIST_HEAD(&addrmap->list6); switch (family) { case AF_INET: { const struct in_addr *addr4 = addr; const struct in_addr *mask4 = mask; map4 = kzalloc(sizeof(*map4), GFP_ATOMIC); if (map4 == NULL) goto cfg_unlbl_map_add_failure; map4->def.type = NETLBL_NLTYPE_UNLABELED; map4->list.addr = addr4->s_addr & mask4->s_addr; map4->list.mask = mask4->s_addr; map4->list.valid = 1; ret_val = netlbl_af4list_add(&map4->list, &addrmap->list4); if (ret_val != 0) goto cfg_unlbl_map_add_failure; break; } #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: { const struct in6_addr *addr6 = addr; const struct in6_addr *mask6 = mask; map6 = kzalloc(sizeof(*map6), GFP_ATOMIC); if (map6 == NULL) goto cfg_unlbl_map_add_failure; map6->def.type = NETLBL_NLTYPE_UNLABELED; map6->list.addr = *addr6; map6->list.addr.s6_addr32[0] &= mask6->s6_addr32[0]; map6->list.addr.s6_addr32[1] &= mask6->s6_addr32[1]; map6->list.addr.s6_addr32[2] &= mask6->s6_addr32[2]; map6->list.addr.s6_addr32[3] &= mask6->s6_addr32[3]; map6->list.mask = *mask6; map6->list.valid = 1; ret_val = netlbl_af6list_add(&map6->list, &addrmap->list6); if (ret_val != 0) goto cfg_unlbl_map_add_failure; break; } #endif /* IPv6 */ default: goto cfg_unlbl_map_add_failure; } entry->def.addrsel = addrmap; entry->def.type = NETLBL_NLTYPE_ADDRSELECT; } else { ret_val = -EINVAL; goto cfg_unlbl_map_add_failure; } ret_val = netlbl_domhsh_add(entry, audit_info); if (ret_val != 0) goto cfg_unlbl_map_add_failure; return 0; cfg_unlbl_map_add_failure: kfree(entry->domain); kfree(entry); kfree(addrmap); kfree(map4); kfree(map6); return ret_val; } /** * netlbl_cfg_unlbl_static_add - Adds a new static label * @net: network namespace * @dev_name: interface name * @addr: IP address in network byte order (struct in[6]_addr) * @mask: address mask in network byte order (struct in[6]_addr) * @family: address family * @secid: LSM secid value for the entry * @audit_info: NetLabel audit information * * Description: * Adds a new NetLabel static label to be used when protocol provided labels * are not present on incoming traffic. If @dev_name is NULL then the default * interface will be used. Returns zero on success, negative values on failure. * */ int netlbl_cfg_unlbl_static_add(struct net *net, const char *dev_name, const void *addr, const void *mask, u16 family, u32 secid, struct netlbl_audit *audit_info) { u32 addr_len; switch (family) { case AF_INET: addr_len = sizeof(struct in_addr); break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: addr_len = sizeof(struct in6_addr); break; #endif /* IPv6 */ default: return -EPFNOSUPPORT; } return netlbl_unlhsh_add(net, dev_name, addr, mask, addr_len, secid, audit_info); } /** * netlbl_cfg_unlbl_static_del - Removes an existing static label * @net: network namespace * @dev_name: interface name * @addr: IP address in network byte order (struct in[6]_addr) * @mask: address mask in network byte order (struct in[6]_addr) * @family: address family * @audit_info: NetLabel audit information * * Description: * Removes an existing NetLabel static label used when protocol provided labels * are not present on incoming traffic. If @dev_name is NULL then the default * interface will be used. Returns zero on success, negative values on failure. * */ int netlbl_cfg_unlbl_static_del(struct net *net, const char *dev_name, const void *addr, const void *mask, u16 family, struct netlbl_audit *audit_info) { u32 addr_len; switch (family) { case AF_INET: addr_len = sizeof(struct in_addr); break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: addr_len = sizeof(struct in6_addr); break; #endif /* IPv6 */ default: return -EPFNOSUPPORT; } return netlbl_unlhsh_remove(net, dev_name, addr, mask, addr_len, audit_info); } /** * netlbl_cfg_cipsov4_add - Add a new CIPSOv4 DOI definition * @doi_def: CIPSO DOI definition * @audit_info: NetLabel audit information * * Description: * Add a new CIPSO DOI definition as defined by @doi_def. Returns zero on * success and negative values on failure. * */ int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def, struct netlbl_audit *audit_info) { return cipso_v4_doi_add(doi_def, audit_info); } /** * netlbl_cfg_cipsov4_del - Remove an existing CIPSOv4 DOI definition * @doi: CIPSO DOI * @audit_info: NetLabel audit information * * Description: * Remove an existing CIPSO DOI definition matching @doi. Returns zero on * success and negative values on failure. * */ void netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info) { cipso_v4_doi_remove(doi, audit_info); } /** * netlbl_cfg_cipsov4_map_add - Add a new CIPSOv4 DOI mapping * @doi: the CIPSO DOI * @domain: the domain mapping to add * @addr: IP address * @mask: IP address mask * @audit_info: NetLabel audit information * * Description: * Add a new NetLabel/LSM domain mapping for the given CIPSO DOI to the NetLabel * subsystem. A @domain value of NULL adds a new default domain mapping. * Returns zero on success, negative values on failure. * */ int netlbl_cfg_cipsov4_map_add(u32 doi, const char *domain, const struct in_addr *addr, const struct in_addr *mask, struct netlbl_audit *audit_info) { int ret_val = -ENOMEM; struct cipso_v4_doi *doi_def; struct netlbl_dom_map *entry; struct netlbl_domaddr_map *addrmap = NULL; struct netlbl_domaddr4_map *addrinfo = NULL; doi_def = cipso_v4_doi_getdef(doi); if (doi_def == NULL) return -ENOENT; entry = kzalloc(sizeof(*entry), GFP_ATOMIC); if (entry == NULL) goto out_entry; entry->family = AF_INET; if (domain != NULL) { entry->domain = kstrdup(domain, GFP_ATOMIC); if (entry->domain == NULL) goto out_domain; } if (addr == NULL && mask == NULL) { entry->def.cipso = doi_def; entry->def.type = NETLBL_NLTYPE_CIPSOV4; } else if (addr != NULL && mask != NULL) { addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC); if (addrmap == NULL) goto out_addrmap; INIT_LIST_HEAD(&addrmap->list4); INIT_LIST_HEAD(&addrmap->list6); addrinfo = kzalloc(sizeof(*addrinfo), GFP_ATOMIC); if (addrinfo == NULL) goto out_addrinfo; addrinfo->def.cipso = doi_def; addrinfo->def.type = NETLBL_NLTYPE_CIPSOV4; addrinfo->list.addr = addr->s_addr & mask->s_addr; addrinfo->list.mask = mask->s_addr; addrinfo->list.valid = 1; ret_val = netlbl_af4list_add(&addrinfo->list, &addrmap->list4); if (ret_val != 0) goto cfg_cipsov4_map_add_failure; entry->def.addrsel = addrmap; entry->def.type = NETLBL_NLTYPE_ADDRSELECT; } else { ret_val = -EINVAL; goto out_addrmap; } ret_val = netlbl_domhsh_add(entry, audit_info); if (ret_val != 0) goto cfg_cipsov4_map_add_failure; return 0; cfg_cipsov4_map_add_failure: kfree(addrinfo); out_addrinfo: kfree(addrmap); out_addrmap: kfree(entry->domain); out_domain: kfree(entry); out_entry: cipso_v4_doi_putdef(doi_def); return ret_val; } /** * netlbl_cfg_calipso_add - Add a new CALIPSO DOI definition * @doi_def: CALIPSO DOI definition * @audit_info: NetLabel audit information * * Description: * Add a new CALIPSO DOI definition as defined by @doi_def. Returns zero on * success and negative values on failure. * */ int netlbl_cfg_calipso_add(struct calipso_doi *doi_def, struct netlbl_audit *audit_info) { #if IS_ENABLED(CONFIG_IPV6) return calipso_doi_add(doi_def, audit_info); #else /* IPv6 */ return -ENOSYS; #endif /* IPv6 */ } /** * netlbl_cfg_calipso_del - Remove an existing CALIPSO DOI definition * @doi: CALIPSO DOI * @audit_info: NetLabel audit information * * Description: * Remove an existing CALIPSO DOI definition matching @doi. Returns zero on * success and negative values on failure. * */ void netlbl_cfg_calipso_del(u32 doi, struct netlbl_audit *audit_info) { #if IS_ENABLED(CONFIG_IPV6) calipso_doi_remove(doi, audit_info); #endif /* IPv6 */ } /** * netlbl_cfg_calipso_map_add - Add a new CALIPSO DOI mapping * @doi: the CALIPSO DOI * @domain: the domain mapping to add * @addr: IP address * @mask: IP address mask * @audit_info: NetLabel audit information * * Description: * Add a new NetLabel/LSM domain mapping for the given CALIPSO DOI to the * NetLabel subsystem. A @domain value of NULL adds a new default domain * mapping. Returns zero on success, negative values on failure. * */ int netlbl_cfg_calipso_map_add(u32 doi, const char *domain, const struct in6_addr *addr, const struct in6_addr *mask, struct netlbl_audit *audit_info) { #if IS_ENABLED(CONFIG_IPV6) int ret_val = -ENOMEM; struct calipso_doi *doi_def; struct netlbl_dom_map *entry; struct netlbl_domaddr_map *addrmap = NULL; struct netlbl_domaddr6_map *addrinfo = NULL; doi_def = calipso_doi_getdef(doi); if (doi_def == NULL) return -ENOENT; entry = kzalloc(sizeof(*entry), GFP_ATOMIC); if (entry == NULL) goto out_entry; entry->family = AF_INET6; if (domain != NULL) { entry->domain = kstrdup(domain, GFP_ATOMIC); if (entry->domain == NULL) goto out_domain; } if (addr == NULL && mask == NULL) { entry->def.calipso = doi_def; entry->def.type = NETLBL_NLTYPE_CALIPSO; } else if (addr != NULL && mask != NULL) { addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC); if (addrmap == NULL) goto out_addrmap; INIT_LIST_HEAD(&addrmap->list4); INIT_LIST_HEAD(&addrmap->list6); addrinfo = kzalloc(sizeof(*addrinfo), GFP_ATOMIC); if (addrinfo == NULL) goto out_addrinfo; addrinfo->def.calipso = doi_def; addrinfo->def.type = NETLBL_NLTYPE_CALIPSO; addrinfo->list.addr = *addr; addrinfo->list.addr.s6_addr32[0] &= mask->s6_addr32[0]; addrinfo->list.addr.s6_addr32[1] &= mask->s6_addr32[1]; addrinfo->list.addr.s6_addr32[2] &= mask->s6_addr32[2]; addrinfo->list.addr.s6_addr32[3] &= mask->s6_addr32[3]; addrinfo->list.mask = *mask; addrinfo->list.valid = 1; ret_val = netlbl_af6list_add(&addrinfo->list, &addrmap->list6); if (ret_val != 0) goto cfg_calipso_map_add_failure; entry->def.addrsel = addrmap; entry->def.type = NETLBL_NLTYPE_ADDRSELECT; } else { ret_val = -EINVAL; goto out_addrmap; } ret_val = netlbl_domhsh_add(entry, audit_info); if (ret_val != 0) goto cfg_calipso_map_add_failure; return 0; cfg_calipso_map_add_failure: kfree(addrinfo); out_addrinfo: kfree(addrmap); out_addrmap: kfree(entry->domain); out_domain: kfree(entry); out_entry: calipso_doi_putdef(doi_def); return ret_val; #else /* IPv6 */ return -ENOSYS; #endif /* IPv6 */ } /* * Security Attribute Functions */ #define _CM_F_NONE 0x00000000 #define _CM_F_ALLOC 0x00000001 #define _CM_F_WALK 0x00000002 /** * _netlbl_catmap_getnode - Get a individual node from a catmap * @catmap: pointer to the category bitmap * @offset: the requested offset * @cm_flags: catmap flags, see _CM_F_* * @gfp_flags: memory allocation flags * * Description: * Iterate through the catmap looking for the node associated with @offset. * If the _CM_F_ALLOC flag is set in @cm_flags and there is no associated node, * one will be created and inserted into the catmap. If the _CM_F_WALK flag is * set in @cm_flags and there is no associated node, the next highest node will * be returned. Returns a pointer to the node on success, NULL on failure. * */ static struct netlbl_lsm_catmap *_netlbl_catmap_getnode( struct netlbl_lsm_catmap **catmap, u32 offset, unsigned int cm_flags, gfp_t gfp_flags) { struct netlbl_lsm_catmap *iter = *catmap; struct netlbl_lsm_catmap *prev = NULL; if (iter == NULL) goto catmap_getnode_alloc; if (offset < iter->startbit) goto catmap_getnode_walk; while (iter && offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) { prev = iter; iter = iter->next; } if (iter == NULL || offset < iter->startbit) goto catmap_getnode_walk; return iter; catmap_getnode_walk: if (cm_flags & _CM_F_WALK) return iter; catmap_getnode_alloc: if (!(cm_flags & _CM_F_ALLOC)) return NULL; iter = netlbl_catmap_alloc(gfp_flags); if (iter == NULL) return NULL; iter->startbit = offset & ~(NETLBL_CATMAP_SIZE - 1); if (prev == NULL) { iter->next = *catmap; *catmap = iter; } else { iter->next = prev->next; prev->next = iter; } return iter; } /** * netlbl_catmap_walk - Walk a LSM secattr catmap looking for a bit * @catmap: the category bitmap * @offset: the offset to start searching at, in bits * * Description: * This function walks a LSM secattr category bitmap starting at @offset and * returns the spot of the first set bit or -ENOENT if no bits are set. * */ int netlbl_catmap_walk(struct netlbl_lsm_catmap *catmap, u32 offset) { struct netlbl_lsm_catmap *iter; u32 idx; u32 bit; NETLBL_CATMAP_MAPTYPE bitmap; iter = _netlbl_catmap_getnode(&catmap, offset, _CM_F_WALK, 0); if (iter == NULL) return -ENOENT; if (offset > iter->startbit) { offset -= iter->startbit; idx = offset / NETLBL_CATMAP_MAPSIZE; bit = offset % NETLBL_CATMAP_MAPSIZE; } else { idx = 0; bit = 0; } bitmap = iter->bitmap[idx] >> bit; for (;;) { if (bitmap != 0) { while ((bitmap & NETLBL_CATMAP_BIT) == 0) { bitmap >>= 1; bit++; } return iter->startbit + (NETLBL_CATMAP_MAPSIZE * idx) + bit; } if (++idx >= NETLBL_CATMAP_MAPCNT) { if (iter->next != NULL) { iter = iter->next; idx = 0; } else return -ENOENT; } bitmap = iter->bitmap[idx]; bit = 0; } return -ENOENT; } EXPORT_SYMBOL(netlbl_catmap_walk); /** * netlbl_catmap_walkrng - Find the end of a string of set bits * @catmap: the category bitmap * @offset: the offset to start searching at, in bits * * Description: * This function walks a LSM secattr category bitmap starting at @offset and * returns the spot of the first cleared bit or -ENOENT if the offset is past * the end of the bitmap. * */ int netlbl_catmap_walkrng(struct netlbl_lsm_catmap *catmap, u32 offset) { struct netlbl_lsm_catmap *iter; struct netlbl_lsm_catmap *prev = NULL; u32 idx; u32 bit; NETLBL_CATMAP_MAPTYPE bitmask; NETLBL_CATMAP_MAPTYPE bitmap; iter = _netlbl_catmap_getnode(&catmap, offset, _CM_F_WALK, 0); if (iter == NULL) return -ENOENT; if (offset > iter->startbit) { offset -= iter->startbit; idx = offset / NETLBL_CATMAP_MAPSIZE; bit = offset % NETLBL_CATMAP_MAPSIZE; } else { idx = 0; bit = 0; } bitmask = NETLBL_CATMAP_BIT << bit; for (;;) { bitmap = iter->bitmap[idx]; while (bitmask != 0 && (bitmap & bitmask) != 0) { bitmask <<= 1; bit++; } if (prev && idx == 0 && bit == 0) return prev->startbit + NETLBL_CATMAP_SIZE - 1; else if (bitmask != 0) return iter->startbit + (NETLBL_CATMAP_MAPSIZE * idx) + bit - 1; else if (++idx >= NETLBL_CATMAP_MAPCNT) { if (iter->next == NULL) return iter->startbit + NETLBL_CATMAP_SIZE - 1; prev = iter; iter = iter->next; idx = 0; } bitmask = NETLBL_CATMAP_BIT; bit = 0; } return -ENOENT; } /** * netlbl_catmap_getlong - Export an unsigned long bitmap * @catmap: pointer to the category bitmap * @offset: pointer to the requested offset * @bitmap: the exported bitmap * * Description: * Export a bitmap with an offset greater than or equal to @offset and return * it in @bitmap. The @offset must be aligned to an unsigned long and will be * updated on return if different from what was requested; if the catmap is * empty at the requested offset and beyond, the @offset is set to (u32)-1. * Returns zero on success, negative values on failure. * */ int netlbl_catmap_getlong(struct netlbl_lsm_catmap *catmap, u32 *offset, unsigned long *bitmap) { struct netlbl_lsm_catmap *iter; u32 off = *offset; u32 idx; /* only allow aligned offsets */ if ((off & (BITS_PER_LONG - 1)) != 0) return -EINVAL; /* a null catmap is equivalent to an empty one */ if (!catmap) { *offset = (u32)-1; return 0; } if (off < catmap->startbit) { off = catmap->startbit; *offset = off; } iter = _netlbl_catmap_getnode(&catmap, off, _CM_F_WALK, 0); if (iter == NULL) { *offset = (u32)-1; return 0; } if (off < iter->startbit) { *offset = iter->startbit; off = 0; } else off -= iter->startbit; idx = off / NETLBL_CATMAP_MAPSIZE; *bitmap = iter->bitmap[idx] >> (off % NETLBL_CATMAP_MAPSIZE); return 0; } /** * netlbl_catmap_setbit - Set a bit in a LSM secattr catmap * @catmap: pointer to the category bitmap * @bit: the bit to set * @flags: memory allocation flags * * Description: * Set the bit specified by @bit in @catmap. Returns zero on success, * negative values on failure. * */ int netlbl_catmap_setbit(struct netlbl_lsm_catmap **catmap, u32 bit, gfp_t flags) { struct netlbl_lsm_catmap *iter; u32 idx; iter = _netlbl_catmap_getnode(catmap, bit, _CM_F_ALLOC, flags); if (iter == NULL) return -ENOMEM; bit -= iter->startbit; idx = bit / NETLBL_CATMAP_MAPSIZE; iter->bitmap[idx] |= NETLBL_CATMAP_BIT << (bit % NETLBL_CATMAP_MAPSIZE); return 0; } EXPORT_SYMBOL(netlbl_catmap_setbit); /** * netlbl_catmap_setrng - Set a range of bits in a LSM secattr catmap * @catmap: pointer to the category bitmap * @start: the starting bit * @end: the last bit in the string * @flags: memory allocation flags * * Description: * Set a range of bits, starting at @start and ending with @end. Returns zero * on success, negative values on failure. * */ int netlbl_catmap_setrng(struct netlbl_lsm_catmap **catmap, u32 start, u32 end, gfp_t flags) { int rc = 0; u32 spot = start; while (rc == 0 && spot <= end) { if (((spot & (BITS_PER_LONG - 1)) == 0) && ((end - spot) > BITS_PER_LONG)) { rc = netlbl_catmap_setlong(catmap, spot, (unsigned long)-1, flags); spot += BITS_PER_LONG; } else rc = netlbl_catmap_setbit(catmap, spot++, flags); } return rc; } /** * netlbl_catmap_setlong - Import an unsigned long bitmap * @catmap: pointer to the category bitmap * @offset: offset to the start of the imported bitmap * @bitmap: the bitmap to import * @flags: memory allocation flags * * Description: * Import the bitmap specified in @bitmap into @catmap, using the offset * in @offset. The offset must be aligned to an unsigned long. Returns zero * on success, negative values on failure. * */ int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap, u32 offset, unsigned long bitmap, gfp_t flags) { struct netlbl_lsm_catmap *iter; u32 idx; /* only allow aligned offsets */ if ((offset & (BITS_PER_LONG - 1)) != 0) return -EINVAL; iter = _netlbl_catmap_getnode(catmap, offset, _CM_F_ALLOC, flags); if (iter == NULL) return -ENOMEM; offset -= iter->startbit; idx = offset / NETLBL_CATMAP_MAPSIZE; iter->bitmap[idx] |= (NETLBL_CATMAP_MAPTYPE)bitmap << (offset % NETLBL_CATMAP_MAPSIZE); return 0; } /* Bitmap functions */ /** * netlbl_bitmap_walk - Walk a bitmap looking for a bit * @bitmap: the bitmap * @bitmap_len: length in bits * @offset: starting offset * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit * * Description: * Starting at @offset, walk the bitmap from left to right until either the * desired bit is found or we reach the end. Return the bit offset, -1 if * not found, or -2 if error. */ int netlbl_bitmap_walk(const unsigned char *bitmap, u32 bitmap_len, u32 offset, u8 state) { u32 bit_spot; u32 byte_offset; unsigned char bitmask; unsigned char byte; if (offset >= bitmap_len) return -1; byte_offset = offset / 8; byte = bitmap[byte_offset]; bit_spot = offset; bitmask = 0x80 >> (offset % 8); while (bit_spot < bitmap_len) { if ((state && (byte & bitmask) == bitmask) || (state == 0 && (byte & bitmask) == 0)) return bit_spot; if (++bit_spot >= bitmap_len) return -1; bitmask >>= 1; if (bitmask == 0) { byte = bitmap[++byte_offset]; bitmask = 0x80; } } return -1; } EXPORT_SYMBOL(netlbl_bitmap_walk); /** * netlbl_bitmap_setbit - Sets a single bit in a bitmap * @bitmap: the bitmap * @bit: the bit * @state: if non-zero, set the bit (1) else clear the bit (0) * * Description: * Set a single bit in the bitmask. Returns zero on success, negative values * on error. */ void netlbl_bitmap_setbit(unsigned char *bitmap, u32 bit, u8 state) { u32 byte_spot; u8 bitmask; /* gcc always rounds to zero when doing integer division */ byte_spot = bit / 8; bitmask = 0x80 >> (bit % 8); if (state) bitmap[byte_spot] |= bitmask; else bitmap[byte_spot] &= ~bitmask; } EXPORT_SYMBOL(netlbl_bitmap_setbit); /* * LSM Functions */ /** * netlbl_enabled - Determine if the NetLabel subsystem is enabled * * Description: * The LSM can use this function to determine if it should use NetLabel * security attributes in it's enforcement mechanism. Currently, NetLabel is * considered to be enabled when it's configuration contains a valid setup for * at least one labeled protocol (i.e. NetLabel can understand incoming * labeled packets of at least one type); otherwise NetLabel is considered to * be disabled. * */ int netlbl_enabled(void) { /* At some point we probably want to expose this mechanism to the user * as well so that admins can toggle NetLabel regardless of the * configuration */ return (atomic_read(&netlabel_mgmt_protocount) > 0); } /** * netlbl_sock_setattr - Label a socket using the correct protocol * @sk: the socket to label * @family: protocol family * @secattr: the security attributes * * Description: * Attach the correct label to the given socket using the security attributes * specified in @secattr. This function requires exclusive access to @sk, * which means it either needs to be in the process of being created or locked. * Returns zero on success, -EDESTADDRREQ if the domain is configured to use * network address selectors (can't blindly label the socket), and negative * values on all other failures. * */ int netlbl_sock_setattr(struct sock *sk, u16 family, const struct netlbl_lsm_secattr *secattr) { int ret_val; struct netlbl_dom_map *dom_entry; rcu_read_lock(); dom_entry = netlbl_domhsh_getentry(secattr->domain, family); if (dom_entry == NULL) { ret_val = -ENOENT; goto socket_setattr_return; } switch (family) { case AF_INET: switch (dom_entry->def.type) { case NETLBL_NLTYPE_ADDRSELECT: ret_val = -EDESTADDRREQ; break; case NETLBL_NLTYPE_CIPSOV4: ret_val = cipso_v4_sock_setattr(sk, dom_entry->def.cipso, secattr); break; case NETLBL_NLTYPE_UNLABELED: ret_val = 0; break; default: ret_val = -ENOENT; } break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: switch (dom_entry->def.type) { case NETLBL_NLTYPE_ADDRSELECT: ret_val = -EDESTADDRREQ; break; case NETLBL_NLTYPE_CALIPSO: ret_val = calipso_sock_setattr(sk, dom_entry->def.calipso, secattr); break; case NETLBL_NLTYPE_UNLABELED: ret_val = 0; break; default: ret_val = -ENOENT; } break; #endif /* IPv6 */ default: ret_val = -EPROTONOSUPPORT; } socket_setattr_return: rcu_read_unlock(); return ret_val; } /** * netlbl_sock_delattr - Delete all the NetLabel labels on a socket * @sk: the socket * * Description: * Remove all the NetLabel labeling from @sk. The caller is responsible for * ensuring that @sk is locked. * */ void netlbl_sock_delattr(struct sock *sk) { switch (sk->sk_family) { case AF_INET: cipso_v4_sock_delattr(sk); break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: calipso_sock_delattr(sk); break; #endif /* IPv6 */ } } /** * netlbl_sock_getattr - Determine the security attributes of a sock * @sk: the sock * @secattr: the security attributes * * Description: * Examines the given sock to see if any NetLabel style labeling has been * applied to the sock, if so it parses the socket label and returns the * security attributes in @secattr. Returns zero on success, negative values * on failure. * */ int netlbl_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) { int ret_val; switch (sk->sk_family) { case AF_INET: ret_val = cipso_v4_sock_getattr(sk, secattr); break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: ret_val = calipso_sock_getattr(sk, secattr); break; #endif /* IPv6 */ default: ret_val = -EPROTONOSUPPORT; } return ret_val; } /** * netlbl_conn_setattr - Label a connected socket using the correct protocol * @sk: the socket to label * @addr: the destination address * @secattr: the security attributes * * Description: * Attach the correct label to the given connected socket using the security * attributes specified in @secattr. The caller is responsible for ensuring * that @sk is locked. Returns zero on success, negative values on failure. * */ int netlbl_conn_setattr(struct sock *sk, struct sockaddr *addr, const struct netlbl_lsm_secattr *secattr) { int ret_val; struct sockaddr_in *addr4; #if IS_ENABLED(CONFIG_IPV6) struct sockaddr_in6 *addr6; #endif struct netlbl_dommap_def *entry; rcu_read_lock(); switch (addr->sa_family) { case AF_INET: addr4 = (struct sockaddr_in *)addr; entry = netlbl_domhsh_getentry_af4(secattr->domain, addr4->sin_addr.s_addr); if (entry == NULL) { ret_val = -ENOENT; goto conn_setattr_return; } switch (entry->type) { case NETLBL_NLTYPE_CIPSOV4: ret_val = cipso_v4_sock_setattr(sk, entry->cipso, secattr); break; case NETLBL_NLTYPE_UNLABELED: /* just delete the protocols we support for right now * but we could remove other protocols if needed */ netlbl_sock_delattr(sk); ret_val = 0; break; default: ret_val = -ENOENT; } break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: addr6 = (struct sockaddr_in6 *)addr; entry = netlbl_domhsh_getentry_af6(secattr->domain, &addr6->sin6_addr); if (entry == NULL) { ret_val = -ENOENT; goto conn_setattr_return; } switch (entry->type) { case NETLBL_NLTYPE_CALIPSO: ret_val = calipso_sock_setattr(sk, entry->calipso, secattr); break; case NETLBL_NLTYPE_UNLABELED: /* just delete the protocols we support for right now * but we could remove other protocols if needed */ netlbl_sock_delattr(sk); ret_val = 0; break; default: ret_val = -ENOENT; } break; #endif /* IPv6 */ default: ret_val = -EPROTONOSUPPORT; } conn_setattr_return: rcu_read_unlock(); return ret_val; } /** * netlbl_req_setattr - Label a request socket using the correct protocol * @req: the request socket to label * @secattr: the security attributes * * Description: * Attach the correct label to the given socket using the security attributes * specified in @secattr. Returns zero on success, negative values on failure. * */ int netlbl_req_setattr(struct request_sock *req, const struct netlbl_lsm_secattr *secattr) { int ret_val; struct netlbl_dommap_def *entry; struct inet_request_sock *ireq = inet_rsk(req); rcu_read_lock(); switch (req->rsk_ops->family) { case AF_INET: entry = netlbl_domhsh_getentry_af4(secattr->domain, ireq->ir_rmt_addr); if (entry == NULL) { ret_val = -ENOENT; goto req_setattr_return; } switch (entry->type) { case NETLBL_NLTYPE_CIPSOV4: ret_val = cipso_v4_req_setattr(req, entry->cipso, secattr); break; case NETLBL_NLTYPE_UNLABELED: netlbl_req_delattr(req); ret_val = 0; break; default: ret_val = -ENOENT; } break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: entry = netlbl_domhsh_getentry_af6(secattr->domain, &ireq->ir_v6_rmt_addr); if (entry == NULL) { ret_val = -ENOENT; goto req_setattr_return; } switch (entry->type) { case NETLBL_NLTYPE_CALIPSO: ret_val = calipso_req_setattr(req, entry->calipso, secattr); break; case NETLBL_NLTYPE_UNLABELED: netlbl_req_delattr(req); ret_val = 0; break; default: ret_val = -ENOENT; } break; #endif /* IPv6 */ default: ret_val = -EPROTONOSUPPORT; } req_setattr_return: rcu_read_unlock(); return ret_val; } /** * netlbl_req_delattr - Delete all the NetLabel labels on a socket * @req: the socket * * Description: * Remove all the NetLabel labeling from @req. * */ void netlbl_req_delattr(struct request_sock *req) { switch (req->rsk_ops->family) { case AF_INET: cipso_v4_req_delattr(req); break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: calipso_req_delattr(req); break; #endif /* IPv6 */ } } /** * netlbl_skbuff_setattr - Label a packet using the correct protocol * @skb: the packet * @family: protocol family * @secattr: the security attributes * * Description: * Attach the correct label to the given packet using the security attributes * specified in @secattr. Returns zero on success, negative values on failure. * */ int netlbl_skbuff_setattr(struct sk_buff *skb, u16 family, const struct netlbl_lsm_secattr *secattr) { int ret_val; struct iphdr *hdr4; #if IS_ENABLED(CONFIG_IPV6) struct ipv6hdr *hdr6; #endif struct netlbl_dommap_def *entry; rcu_read_lock(); switch (family) { case AF_INET: hdr4 = ip_hdr(skb); entry = netlbl_domhsh_getentry_af4(secattr->domain, hdr4->daddr); if (entry == NULL) { ret_val = -ENOENT; goto skbuff_setattr_return; } switch (entry->type) { case NETLBL_NLTYPE_CIPSOV4: ret_val = cipso_v4_skbuff_setattr(skb, entry->cipso, secattr); break; case NETLBL_NLTYPE_UNLABELED: /* just delete the protocols we support for right now * but we could remove other protocols if needed */ ret_val = cipso_v4_skbuff_delattr(skb); break; default: ret_val = -ENOENT; } break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: hdr6 = ipv6_hdr(skb); entry = netlbl_domhsh_getentry_af6(secattr->domain, &hdr6->daddr); if (entry == NULL) { ret_val = -ENOENT; goto skbuff_setattr_return; } switch (entry->type) { case NETLBL_NLTYPE_CALIPSO: ret_val = calipso_skbuff_setattr(skb, entry->calipso, secattr); break; case NETLBL_NLTYPE_UNLABELED: /* just delete the protocols we support for right now * but we could remove other protocols if needed */ ret_val = calipso_skbuff_delattr(skb); break; default: ret_val = -ENOENT; } break; #endif /* IPv6 */ default: ret_val = -EPROTONOSUPPORT; } skbuff_setattr_return: rcu_read_unlock(); return ret_val; } /** * netlbl_skbuff_getattr - Determine the security attributes of a packet * @skb: the packet * @family: protocol family * @secattr: the security attributes * * Description: * Examines the given packet to see if a recognized form of packet labeling * is present, if so it parses the packet label and returns the security * attributes in @secattr. Returns zero on success, negative values on * failure. * */ int netlbl_skbuff_getattr(const struct sk_buff *skb, u16 family, struct netlbl_lsm_secattr *secattr) { unsigned char *ptr; switch (family) { case AF_INET: ptr = cipso_v4_optptr(skb); if (ptr && cipso_v4_getattr(ptr, secattr) == 0) return 0; break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: ptr = calipso_optptr(skb); if (ptr && calipso_getattr(ptr, secattr) == 0) return 0; break; #endif /* IPv6 */ } return netlbl_unlabel_getattr(skb, family, secattr); } /** * netlbl_skbuff_err - Handle a LSM error on a sk_buff * @skb: the packet * @family: the family * @error: the error code * @gateway: true if host is acting as a gateway, false otherwise * * Description: * Deal with a LSM problem when handling the packet in @skb, typically this is * a permission denied problem (-EACCES). The correct action is determined * according to the packet's labeling protocol. * */ void netlbl_skbuff_err(struct sk_buff *skb, u16 family, int error, int gateway) { switch (family) { case AF_INET: if (cipso_v4_optptr(skb)) cipso_v4_error(skb, error, gateway); break; } } /** * netlbl_cache_invalidate - Invalidate all of the NetLabel protocol caches * * Description: * For all of the NetLabel protocols that support some form of label mapping * cache, invalidate the cache. Returns zero on success, negative values on * error. * */ void netlbl_cache_invalidate(void) { cipso_v4_cache_invalidate(); #if IS_ENABLED(CONFIG_IPV6) calipso_cache_invalidate(); #endif /* IPv6 */ } /** * netlbl_cache_add - Add an entry to a NetLabel protocol cache * @skb: the packet * @family: the family * @secattr: the packet's security attributes * * Description: * Add the LSM security attributes for the given packet to the underlying * NetLabel protocol's label mapping cache. Returns zero on success, negative * values on error. * */ int netlbl_cache_add(const struct sk_buff *skb, u16 family, const struct netlbl_lsm_secattr *secattr) { unsigned char *ptr; if ((secattr->flags & NETLBL_SECATTR_CACHE) == 0) return -ENOMSG; switch (family) { case AF_INET: ptr = cipso_v4_optptr(skb); if (ptr) return cipso_v4_cache_add(ptr, secattr); break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: ptr = calipso_optptr(skb); if (ptr) return calipso_cache_add(ptr, secattr); break; #endif /* IPv6 */ } return -ENOMSG; } /* * Protocol Engine Functions */ /** * netlbl_audit_start - Start an audit message * @type: audit message type * @audit_info: NetLabel audit information * * Description: * Start an audit message using the type specified in @type and fill the audit * message with some fields common to all NetLabel audit messages. This * function should only be used by protocol engines, not LSMs. Returns a * pointer to the audit buffer on success, NULL on failure. * */ struct audit_buffer *netlbl_audit_start(int type, struct netlbl_audit *audit_info) { return netlbl_audit_start_common(type, audit_info); } EXPORT_SYMBOL(netlbl_audit_start); /* * Setup Functions */ /** * netlbl_init - Initialize NetLabel * * Description: * Perform the required NetLabel initialization before first use. * */ static int __init netlbl_init(void) { int ret_val; printk(KERN_INFO "NetLabel: Initializing\n"); printk(KERN_INFO "NetLabel: domain hash size = %u\n", (1 << NETLBL_DOMHSH_BITSIZE)); printk(KERN_INFO "NetLabel: protocols = UNLABELED CIPSOv4 CALIPSO\n"); ret_val = netlbl_domhsh_init(NETLBL_DOMHSH_BITSIZE); if (ret_val != 0) goto init_failure; ret_val = netlbl_unlabel_init(NETLBL_UNLHSH_BITSIZE); if (ret_val != 0) goto init_failure; ret_val = netlbl_netlink_init(); if (ret_val != 0) goto init_failure; ret_val = netlbl_unlabel_defconf(); if (ret_val != 0) goto init_failure; printk(KERN_INFO "NetLabel: unlabeled traffic allowed by default\n"); return 0; init_failure: panic("NetLabel: failed to initialize properly (%d)\n", ret_val); } subsys_initcall(netlbl_init);
linux-master
net/netlabel/netlabel_kapi.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NetLabel Network Address Lists * * This file contains network address list functions used to manage ordered * lists of network addresses for use by the NetLabel subsystem. The NetLabel * system manages static and dynamic label mappings for network protocols such * as CIPSO and RIPSO. * * Author: Paul Moore <[email protected]> */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2008 */ #include <linux/types.h> #include <linux/rcupdate.h> #include <linux/list.h> #include <linux/spinlock.h> #include <linux/in.h> #include <linux/in6.h> #include <linux/ip.h> #include <linux/ipv6.h> #include <net/ip.h> #include <net/ipv6.h> #include <linux/audit.h> #include "netlabel_addrlist.h" /* * Address List Functions */ /** * netlbl_af4list_search - Search for a matching IPv4 address entry * @addr: IPv4 address * @head: the list head * * Description: * Searches the IPv4 address list given by @head. If a matching address entry * is found it is returned, otherwise NULL is returned. The caller is * responsible for calling the rcu_read_[un]lock() functions. * */ struct netlbl_af4list *netlbl_af4list_search(__be32 addr, struct list_head *head) { struct netlbl_af4list *iter; list_for_each_entry_rcu(iter, head, list) if (iter->valid && (addr & iter->mask) == iter->addr) return iter; return NULL; } /** * netlbl_af4list_search_exact - Search for an exact IPv4 address entry * @addr: IPv4 address * @mask: IPv4 address mask * @head: the list head * * Description: * Searches the IPv4 address list given by @head. If an exact match if found * it is returned, otherwise NULL is returned. The caller is responsible for * calling the rcu_read_[un]lock() functions. * */ struct netlbl_af4list *netlbl_af4list_search_exact(__be32 addr, __be32 mask, struct list_head *head) { struct netlbl_af4list *iter; list_for_each_entry_rcu(iter, head, list) if (iter->valid && iter->addr == addr && iter->mask == mask) return iter; return NULL; } #if IS_ENABLED(CONFIG_IPV6) /** * netlbl_af6list_search - Search for a matching IPv6 address entry * @addr: IPv6 address * @head: the list head * * Description: * Searches the IPv6 address list given by @head. If a matching address entry * is found it is returned, otherwise NULL is returned. The caller is * responsible for calling the rcu_read_[un]lock() functions. * */ struct netlbl_af6list *netlbl_af6list_search(const struct in6_addr *addr, struct list_head *head) { struct netlbl_af6list *iter; list_for_each_entry_rcu(iter, head, list) if (iter->valid && ipv6_masked_addr_cmp(&iter->addr, &iter->mask, addr) == 0) return iter; return NULL; } /** * netlbl_af6list_search_exact - Search for an exact IPv6 address entry * @addr: IPv6 address * @mask: IPv6 address mask * @head: the list head * * Description: * Searches the IPv6 address list given by @head. If an exact match if found * it is returned, otherwise NULL is returned. The caller is responsible for * calling the rcu_read_[un]lock() functions. * */ struct netlbl_af6list *netlbl_af6list_search_exact(const struct in6_addr *addr, const struct in6_addr *mask, struct list_head *head) { struct netlbl_af6list *iter; list_for_each_entry_rcu(iter, head, list) if (iter->valid && ipv6_addr_equal(&iter->addr, addr) && ipv6_addr_equal(&iter->mask, mask)) return iter; return NULL; } #endif /* IPv6 */ /** * netlbl_af4list_add - Add a new IPv4 address entry to a list * @entry: address entry * @head: the list head * * Description: * Add a new address entry to the list pointed to by @head. On success zero is * returned, otherwise a negative value is returned. The caller is responsible * for calling the necessary locking functions. * */ int netlbl_af4list_add(struct netlbl_af4list *entry, struct list_head *head) { struct netlbl_af4list *iter; iter = netlbl_af4list_search(entry->addr, head); if (iter != NULL && iter->addr == entry->addr && iter->mask == entry->mask) return -EEXIST; /* in order to speed up address searches through the list (the common * case) we need to keep the list in order based on the size of the * address mask such that the entry with the widest mask (smallest * numerical value) appears first in the list */ list_for_each_entry_rcu(iter, head, list) if (iter->valid && ntohl(entry->mask) > ntohl(iter->mask)) { __list_add_rcu(&entry->list, iter->list.prev, &iter->list); return 0; } list_add_tail_rcu(&entry->list, head); return 0; } #if IS_ENABLED(CONFIG_IPV6) /** * netlbl_af6list_add - Add a new IPv6 address entry to a list * @entry: address entry * @head: the list head * * Description: * Add a new address entry to the list pointed to by @head. On success zero is * returned, otherwise a negative value is returned. The caller is responsible * for calling the necessary locking functions. * */ int netlbl_af6list_add(struct netlbl_af6list *entry, struct list_head *head) { struct netlbl_af6list *iter; iter = netlbl_af6list_search(&entry->addr, head); if (iter != NULL && ipv6_addr_equal(&iter->addr, &entry->addr) && ipv6_addr_equal(&iter->mask, &entry->mask)) return -EEXIST; /* in order to speed up address searches through the list (the common * case) we need to keep the list in order based on the size of the * address mask such that the entry with the widest mask (smallest * numerical value) appears first in the list */ list_for_each_entry_rcu(iter, head, list) if (iter->valid && ipv6_addr_cmp(&entry->mask, &iter->mask) > 0) { __list_add_rcu(&entry->list, iter->list.prev, &iter->list); return 0; } list_add_tail_rcu(&entry->list, head); return 0; } #endif /* IPv6 */ /** * netlbl_af4list_remove_entry - Remove an IPv4 address entry * @entry: address entry * * Description: * Remove the specified IP address entry. The caller is responsible for * calling the necessary locking functions. * */ void netlbl_af4list_remove_entry(struct netlbl_af4list *entry) { entry->valid = 0; list_del_rcu(&entry->list); } /** * netlbl_af4list_remove - Remove an IPv4 address entry * @addr: IP address * @mask: IP address mask * @head: the list head * * Description: * Remove an IP address entry from the list pointed to by @head. Returns the * entry on success, NULL on failure. The caller is responsible for calling * the necessary locking functions. * */ struct netlbl_af4list *netlbl_af4list_remove(__be32 addr, __be32 mask, struct list_head *head) { struct netlbl_af4list *entry; entry = netlbl_af4list_search_exact(addr, mask, head); if (entry == NULL) return NULL; netlbl_af4list_remove_entry(entry); return entry; } #if IS_ENABLED(CONFIG_IPV6) /** * netlbl_af6list_remove_entry - Remove an IPv6 address entry * @entry: address entry * * Description: * Remove the specified IP address entry. The caller is responsible for * calling the necessary locking functions. * */ void netlbl_af6list_remove_entry(struct netlbl_af6list *entry) { entry->valid = 0; list_del_rcu(&entry->list); } /** * netlbl_af6list_remove - Remove an IPv6 address entry * @addr: IP address * @mask: IP address mask * @head: the list head * * Description: * Remove an IP address entry from the list pointed to by @head. Returns the * entry on success, NULL on failure. The caller is responsible for calling * the necessary locking functions. * */ struct netlbl_af6list *netlbl_af6list_remove(const struct in6_addr *addr, const struct in6_addr *mask, struct list_head *head) { struct netlbl_af6list *entry; entry = netlbl_af6list_search_exact(addr, mask, head); if (entry == NULL) return NULL; netlbl_af6list_remove_entry(entry); return entry; } #endif /* IPv6 */ /* * Audit Helper Functions */ #ifdef CONFIG_AUDIT /** * netlbl_af4list_audit_addr - Audit an IPv4 address * @audit_buf: audit buffer * @src: true if source address, false if destination * @dev: network interface * @addr: IP address * @mask: IP address mask * * Description: * Write the IPv4 address and address mask, if necessary, to @audit_buf. * */ void netlbl_af4list_audit_addr(struct audit_buffer *audit_buf, int src, const char *dev, __be32 addr, __be32 mask) { u32 mask_val = ntohl(mask); char *dir = (src ? "src" : "dst"); if (dev != NULL) audit_log_format(audit_buf, " netif=%s", dev); audit_log_format(audit_buf, " %s=%pI4", dir, &addr); if (mask_val != 0xffffffff) { u32 mask_len = 0; while (mask_val > 0) { mask_val <<= 1; mask_len++; } audit_log_format(audit_buf, " %s_prefixlen=%d", dir, mask_len); } } #if IS_ENABLED(CONFIG_IPV6) /** * netlbl_af6list_audit_addr - Audit an IPv6 address * @audit_buf: audit buffer * @src: true if source address, false if destination * @dev: network interface * @addr: IP address * @mask: IP address mask * * Description: * Write the IPv6 address and address mask, if necessary, to @audit_buf. * */ void netlbl_af6list_audit_addr(struct audit_buffer *audit_buf, int src, const char *dev, const struct in6_addr *addr, const struct in6_addr *mask) { char *dir = (src ? "src" : "dst"); if (dev != NULL) audit_log_format(audit_buf, " netif=%s", dev); audit_log_format(audit_buf, " %s=%pI6", dir, addr); if (ntohl(mask->s6_addr32[3]) != 0xffffffff) { u32 mask_len = 0; u32 mask_val; int iter = -1; while (ntohl(mask->s6_addr32[++iter]) == 0xffffffff) mask_len += 32; mask_val = ntohl(mask->s6_addr32[iter]); while (mask_val > 0) { mask_val <<= 1; mask_len++; } audit_log_format(audit_buf, " %s_prefixlen=%d", dir, mask_len); } } #endif /* IPv6 */ #endif /* CONFIG_AUDIT */
linux-master
net/netlabel/netlabel_addrlist.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NetLabel NETLINK Interface * * This file defines the NETLINK interface for the NetLabel system. The * NetLabel system manages static and dynamic label mappings for network * protocols such as CIPSO and RIPSO. * * Author: Paul Moore <[email protected]> */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 */ #include <linux/init.h> #include <linux/types.h> #include <linux/list.h> #include <linux/socket.h> #include <linux/audit.h> #include <linux/tty.h> #include <linux/security.h> #include <linux/gfp.h> #include <net/sock.h> #include <net/netlink.h> #include <net/genetlink.h> #include <net/netlabel.h> #include <asm/bug.h> #include "netlabel_mgmt.h" #include "netlabel_unlabeled.h" #include "netlabel_cipso_v4.h" #include "netlabel_calipso.h" #include "netlabel_user.h" /* * NetLabel NETLINK Setup Functions */ /** * netlbl_netlink_init - Initialize the NETLINK communication channel * * Description: * Call out to the NetLabel components so they can register their families and * commands with the Generic NETLINK mechanism. Returns zero on success and * non-zero on failure. * */ int __init netlbl_netlink_init(void) { int ret_val; ret_val = netlbl_mgmt_genl_init(); if (ret_val != 0) return ret_val; ret_val = netlbl_cipsov4_genl_init(); if (ret_val != 0) return ret_val; ret_val = netlbl_calipso_genl_init(); if (ret_val != 0) return ret_val; return netlbl_unlabel_genl_init(); } /* * NetLabel Audit Functions */ /** * netlbl_audit_start_common - Start an audit message * @type: audit message type * @audit_info: NetLabel audit information * * Description: * Start an audit message using the type specified in @type and fill the audit * message with some fields common to all NetLabel audit messages. Returns * a pointer to the audit buffer on success, NULL on failure. * */ struct audit_buffer *netlbl_audit_start_common(int type, struct netlbl_audit *audit_info) { struct audit_buffer *audit_buf; char *secctx; u32 secctx_len; if (audit_enabled == AUDIT_OFF) return NULL; audit_buf = audit_log_start(audit_context(), GFP_ATOMIC, type); if (audit_buf == NULL) return NULL; audit_log_format(audit_buf, "netlabel: auid=%u ses=%u", from_kuid(&init_user_ns, audit_info->loginuid), audit_info->sessionid); if (audit_info->secid != 0 && security_secid_to_secctx(audit_info->secid, &secctx, &secctx_len) == 0) { audit_log_format(audit_buf, " subj=%s", secctx); security_release_secctx(secctx, secctx_len); } return audit_buf; }
linux-master
net/netlabel/netlabel_user.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NetLabel CALIPSO/IPv6 Support * * This file defines the CALIPSO/IPv6 functions for the NetLabel system. The * NetLabel system manages static and dynamic label mappings for network * protocols such as CIPSO and CALIPSO. * * Authors: Paul Moore <[email protected]> * Huw Davies <[email protected]> */ /* (c) Copyright Hewlett-Packard Development Company, L.P., 2006 * (c) Copyright Huw Davies <[email protected]>, 2015 */ #include <linux/types.h> #include <linux/socket.h> #include <linux/string.h> #include <linux/skbuff.h> #include <linux/audit.h> #include <linux/slab.h> #include <net/sock.h> #include <net/netlink.h> #include <net/genetlink.h> #include <net/netlabel.h> #include <net/calipso.h> #include <linux/atomic.h> #include "netlabel_user.h" #include "netlabel_calipso.h" #include "netlabel_mgmt.h" #include "netlabel_domainhash.h" /* Argument struct for calipso_doi_walk() */ struct netlbl_calipso_doiwalk_arg { struct netlink_callback *nl_cb; struct sk_buff *skb; u32 seq; }; /* Argument struct for netlbl_domhsh_walk() */ struct netlbl_domhsh_walk_arg { struct netlbl_audit *audit_info; u32 doi; }; /* NetLabel Generic NETLINK CALIPSO family */ static struct genl_family netlbl_calipso_gnl_family; /* NetLabel Netlink attribute policy */ static const struct nla_policy calipso_genl_policy[NLBL_CALIPSO_A_MAX + 1] = { [NLBL_CALIPSO_A_DOI] = { .type = NLA_U32 }, [NLBL_CALIPSO_A_MTYPE] = { .type = NLA_U32 }, }; /* NetLabel Command Handlers */ /** * netlbl_calipso_add_pass - Adds a CALIPSO pass DOI definition * @info: the Generic NETLINK info block * @audit_info: NetLabel audit information * * Description: * Create a new CALIPSO_MAP_PASS DOI definition based on the given ADD message * and add it to the CALIPSO engine. Return zero on success and non-zero on * error. * */ static int netlbl_calipso_add_pass(struct genl_info *info, struct netlbl_audit *audit_info) { int ret_val; struct calipso_doi *doi_def = NULL; doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL); if (!doi_def) return -ENOMEM; doi_def->type = CALIPSO_MAP_PASS; doi_def->doi = nla_get_u32(info->attrs[NLBL_CALIPSO_A_DOI]); ret_val = calipso_doi_add(doi_def, audit_info); if (ret_val != 0) calipso_doi_free(doi_def); return ret_val; } /** * netlbl_calipso_add - Handle an ADD message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Create a new DOI definition based on the given ADD message and add it to the * CALIPSO engine. Returns zero on success, negative values on failure. * */ static int netlbl_calipso_add(struct sk_buff *skb, struct genl_info *info) { int ret_val = -EINVAL; struct netlbl_audit audit_info; if (!info->attrs[NLBL_CALIPSO_A_DOI] || !info->attrs[NLBL_CALIPSO_A_MTYPE]) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); switch (nla_get_u32(info->attrs[NLBL_CALIPSO_A_MTYPE])) { case CALIPSO_MAP_PASS: ret_val = netlbl_calipso_add_pass(info, &audit_info); break; } if (ret_val == 0) atomic_inc(&netlabel_mgmt_protocount); return ret_val; } /** * netlbl_calipso_list - Handle a LIST message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated LIST message and respond accordingly. * Returns zero on success and negative values on error. * */ static int netlbl_calipso_list(struct sk_buff *skb, struct genl_info *info) { int ret_val; struct sk_buff *ans_skb = NULL; void *data; u32 doi; struct calipso_doi *doi_def; if (!info->attrs[NLBL_CALIPSO_A_DOI]) { ret_val = -EINVAL; goto list_failure; } doi = nla_get_u32(info->attrs[NLBL_CALIPSO_A_DOI]); doi_def = calipso_doi_getdef(doi); if (!doi_def) { ret_val = -EINVAL; goto list_failure; } ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!ans_skb) { ret_val = -ENOMEM; goto list_failure_put; } data = genlmsg_put_reply(ans_skb, info, &netlbl_calipso_gnl_family, 0, NLBL_CALIPSO_C_LIST); if (!data) { ret_val = -ENOMEM; goto list_failure_put; } ret_val = nla_put_u32(ans_skb, NLBL_CALIPSO_A_MTYPE, doi_def->type); if (ret_val != 0) goto list_failure_put; calipso_doi_putdef(doi_def); genlmsg_end(ans_skb, data); return genlmsg_reply(ans_skb, info); list_failure_put: calipso_doi_putdef(doi_def); list_failure: kfree_skb(ans_skb); return ret_val; } /** * netlbl_calipso_listall_cb - calipso_doi_walk() callback for LISTALL * @doi_def: the CALIPSO DOI definition * @arg: the netlbl_calipso_doiwalk_arg structure * * Description: * This function is designed to be used as a callback to the * calipso_doi_walk() function for use in generating a response for a LISTALL * message. Returns the size of the message on success, negative values on * failure. * */ static int netlbl_calipso_listall_cb(struct calipso_doi *doi_def, void *arg) { int ret_val = -ENOMEM; struct netlbl_calipso_doiwalk_arg *cb_arg = arg; void *data; data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid, cb_arg->seq, &netlbl_calipso_gnl_family, NLM_F_MULTI, NLBL_CALIPSO_C_LISTALL); if (!data) goto listall_cb_failure; ret_val = nla_put_u32(cb_arg->skb, NLBL_CALIPSO_A_DOI, doi_def->doi); if (ret_val != 0) goto listall_cb_failure; ret_val = nla_put_u32(cb_arg->skb, NLBL_CALIPSO_A_MTYPE, doi_def->type); if (ret_val != 0) goto listall_cb_failure; genlmsg_end(cb_arg->skb, data); return 0; listall_cb_failure: genlmsg_cancel(cb_arg->skb, data); return ret_val; } /** * netlbl_calipso_listall - Handle a LISTALL message * @skb: the NETLINK buffer * @cb: the NETLINK callback * * Description: * Process a user generated LISTALL message and respond accordingly. Returns * zero on success and negative values on error. * */ static int netlbl_calipso_listall(struct sk_buff *skb, struct netlink_callback *cb) { struct netlbl_calipso_doiwalk_arg cb_arg; u32 doi_skip = cb->args[0]; cb_arg.nl_cb = cb; cb_arg.skb = skb; cb_arg.seq = cb->nlh->nlmsg_seq; calipso_doi_walk(&doi_skip, netlbl_calipso_listall_cb, &cb_arg); cb->args[0] = doi_skip; return skb->len; } /** * netlbl_calipso_remove_cb - netlbl_calipso_remove() callback for REMOVE * @entry: LSM domain mapping entry * @arg: the netlbl_domhsh_walk_arg structure * * Description: * This function is intended for use by netlbl_calipso_remove() as the callback * for the netlbl_domhsh_walk() function; it removes LSM domain map entries * which are associated with the CALIPSO DOI specified in @arg. Returns zero on * success, negative values on failure. * */ static int netlbl_calipso_remove_cb(struct netlbl_dom_map *entry, void *arg) { struct netlbl_domhsh_walk_arg *cb_arg = arg; if (entry->def.type == NETLBL_NLTYPE_CALIPSO && entry->def.calipso->doi == cb_arg->doi) return netlbl_domhsh_remove_entry(entry, cb_arg->audit_info); return 0; } /** * netlbl_calipso_remove - Handle a REMOVE message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated REMOVE message and respond accordingly. Returns * zero on success, negative values on failure. * */ static int netlbl_calipso_remove(struct sk_buff *skb, struct genl_info *info) { int ret_val = -EINVAL; struct netlbl_domhsh_walk_arg cb_arg; struct netlbl_audit audit_info; u32 skip_bkt = 0; u32 skip_chain = 0; if (!info->attrs[NLBL_CALIPSO_A_DOI]) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); cb_arg.doi = nla_get_u32(info->attrs[NLBL_CALIPSO_A_DOI]); cb_arg.audit_info = &audit_info; ret_val = netlbl_domhsh_walk(&skip_bkt, &skip_chain, netlbl_calipso_remove_cb, &cb_arg); if (ret_val == 0 || ret_val == -ENOENT) { ret_val = calipso_doi_remove(cb_arg.doi, &audit_info); if (ret_val == 0) atomic_dec(&netlabel_mgmt_protocount); } return ret_val; } /* NetLabel Generic NETLINK Command Definitions */ static const struct genl_small_ops netlbl_calipso_ops[] = { { .cmd = NLBL_CALIPSO_C_ADD, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_calipso_add, .dumpit = NULL, }, { .cmd = NLBL_CALIPSO_C_REMOVE, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_calipso_remove, .dumpit = NULL, }, { .cmd = NLBL_CALIPSO_C_LIST, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = netlbl_calipso_list, .dumpit = NULL, }, { .cmd = NLBL_CALIPSO_C_LISTALL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = NULL, .dumpit = netlbl_calipso_listall, }, }; static struct genl_family netlbl_calipso_gnl_family __ro_after_init = { .hdrsize = 0, .name = NETLBL_NLTYPE_CALIPSO_NAME, .version = NETLBL_PROTO_VERSION, .maxattr = NLBL_CALIPSO_A_MAX, .policy = calipso_genl_policy, .module = THIS_MODULE, .small_ops = netlbl_calipso_ops, .n_small_ops = ARRAY_SIZE(netlbl_calipso_ops), .resv_start_op = NLBL_CALIPSO_C_LISTALL + 1, }; /* NetLabel Generic NETLINK Protocol Functions */ /** * netlbl_calipso_genl_init - Register the CALIPSO NetLabel component * * Description: * Register the CALIPSO packet NetLabel component with the Generic NETLINK * mechanism. Returns zero on success, negative values on failure. * */ int __init netlbl_calipso_genl_init(void) { return genl_register_family(&netlbl_calipso_gnl_family); } static const struct netlbl_calipso_ops *calipso_ops; /** * netlbl_calipso_ops_register - Register the CALIPSO operations * @ops: ops to register * * Description: * Register the CALIPSO packet engine operations. * */ const struct netlbl_calipso_ops * netlbl_calipso_ops_register(const struct netlbl_calipso_ops *ops) { return xchg(&calipso_ops, ops); } EXPORT_SYMBOL(netlbl_calipso_ops_register); static const struct netlbl_calipso_ops *netlbl_calipso_ops_get(void) { return READ_ONCE(calipso_ops); } /** * calipso_doi_add - Add a new DOI to the CALIPSO protocol engine * @doi_def: the DOI structure * @audit_info: NetLabel audit information * * Description: * The caller defines a new DOI for use by the CALIPSO engine and calls this * function to add it to the list of acceptable domains. The caller must * ensure that the mapping table specified in @doi_def->map meets all of the * requirements of the mapping type (see calipso.h for details). Returns * zero on success and non-zero on failure. * */ int calipso_doi_add(struct calipso_doi *doi_def, struct netlbl_audit *audit_info) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->doi_add(doi_def, audit_info); return ret_val; } /** * calipso_doi_free - Frees a DOI definition * @doi_def: the DOI definition * * Description: * This function frees all of the memory associated with a DOI definition. * */ void calipso_doi_free(struct calipso_doi *doi_def) { const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ops->doi_free(doi_def); } /** * calipso_doi_remove - Remove an existing DOI from the CALIPSO protocol engine * @doi: the DOI value * @audit_info: NetLabel audit information * * Description: * Removes a DOI definition from the CALIPSO engine. The NetLabel routines will * be called to release their own LSM domain mappings as well as our own * domain list. Returns zero on success and negative values on failure. * */ int calipso_doi_remove(u32 doi, struct netlbl_audit *audit_info) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->doi_remove(doi, audit_info); return ret_val; } /** * calipso_doi_getdef - Returns a reference to a valid DOI definition * @doi: the DOI value * * Description: * Searches for a valid DOI definition and if one is found it is returned to * the caller. Otherwise NULL is returned. The caller must ensure that * calipso_doi_putdef() is called when the caller is done. * */ struct calipso_doi *calipso_doi_getdef(u32 doi) { struct calipso_doi *ret_val = NULL; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->doi_getdef(doi); return ret_val; } /** * calipso_doi_putdef - Releases a reference for the given DOI definition * @doi_def: the DOI definition * * Description: * Releases a DOI definition reference obtained from calipso_doi_getdef(). * */ void calipso_doi_putdef(struct calipso_doi *doi_def) { const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ops->doi_putdef(doi_def); } /** * calipso_doi_walk - Iterate through the DOI definitions * @skip_cnt: skip past this number of DOI definitions, updated * @callback: callback for each DOI definition * @cb_arg: argument for the callback function * * Description: * Iterate over the DOI definition list, skipping the first @skip_cnt entries. * For each entry call @callback, if @callback returns a negative value stop * 'walking' through the list and return. Updates the value in @skip_cnt upon * return. Returns zero on success, negative values on failure. * */ int calipso_doi_walk(u32 *skip_cnt, int (*callback)(struct calipso_doi *doi_def, void *arg), void *cb_arg) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->doi_walk(skip_cnt, callback, cb_arg); return ret_val; } /** * calipso_sock_getattr - Get the security attributes from a sock * @sk: the sock * @secattr: the security attributes * * Description: * Query @sk to see if there is a CALIPSO option attached to the sock and if * there is return the CALIPSO security attributes in @secattr. This function * requires that @sk be locked, or privately held, but it does not do any * locking itself. Returns zero on success and negative values on failure. * */ int calipso_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->sock_getattr(sk, secattr); return ret_val; } /** * calipso_sock_setattr - Add a CALIPSO option to a socket * @sk: the socket * @doi_def: the CALIPSO DOI to use * @secattr: the specific security attributes of the socket * * Description: * Set the CALIPSO option on the given socket using the DOI definition and * security attributes passed to the function. This function requires * exclusive access to @sk, which means it either needs to be in the * process of being created or locked. Returns zero on success and negative * values on failure. * */ int calipso_sock_setattr(struct sock *sk, const struct calipso_doi *doi_def, const struct netlbl_lsm_secattr *secattr) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->sock_setattr(sk, doi_def, secattr); return ret_val; } /** * calipso_sock_delattr - Delete the CALIPSO option from a socket * @sk: the socket * * Description: * Removes the CALIPSO option from a socket, if present. * */ void calipso_sock_delattr(struct sock *sk) { const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ops->sock_delattr(sk); } /** * calipso_req_setattr - Add a CALIPSO option to a connection request socket * @req: the connection request socket * @doi_def: the CALIPSO DOI to use * @secattr: the specific security attributes of the socket * * Description: * Set the CALIPSO option on the given socket using the DOI definition and * security attributes passed to the function. Returns zero on success and * negative values on failure. * */ int calipso_req_setattr(struct request_sock *req, const struct calipso_doi *doi_def, const struct netlbl_lsm_secattr *secattr) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->req_setattr(req, doi_def, secattr); return ret_val; } /** * calipso_req_delattr - Delete the CALIPSO option from a request socket * @req: the request socket * * Description: * Removes the CALIPSO option from a request socket, if present. * */ void calipso_req_delattr(struct request_sock *req) { const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ops->req_delattr(req); } /** * calipso_optptr - Find the CALIPSO option in the packet * @skb: the packet * * Description: * Parse the packet's IP header looking for a CALIPSO option. Returns a pointer * to the start of the CALIPSO option on success, NULL if one if not found. * */ unsigned char *calipso_optptr(const struct sk_buff *skb) { unsigned char *ret_val = NULL; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->skbuff_optptr(skb); return ret_val; } /** * calipso_getattr - Get the security attributes from a memory block. * @calipso: the CALIPSO option * @secattr: the security attributes * * Description: * Inspect @calipso and return the security attributes in @secattr. * Returns zero on success and negative values on failure. * */ int calipso_getattr(const unsigned char *calipso, struct netlbl_lsm_secattr *secattr) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->opt_getattr(calipso, secattr); return ret_val; } /** * calipso_skbuff_setattr - Set the CALIPSO option on a packet * @skb: the packet * @doi_def: the CALIPSO DOI to use * @secattr: the security attributes * * Description: * Set the CALIPSO option on the given packet based on the security attributes. * Returns a pointer to the IP header on success and NULL on failure. * */ int calipso_skbuff_setattr(struct sk_buff *skb, const struct calipso_doi *doi_def, const struct netlbl_lsm_secattr *secattr) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->skbuff_setattr(skb, doi_def, secattr); return ret_val; } /** * calipso_skbuff_delattr - Delete any CALIPSO options from a packet * @skb: the packet * * Description: * Removes any and all CALIPSO options from the given packet. Returns zero on * success, negative values on failure. * */ int calipso_skbuff_delattr(struct sk_buff *skb) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->skbuff_delattr(skb); return ret_val; } /** * calipso_cache_invalidate - Invalidates the current CALIPSO cache * * Description: * Invalidates and frees any entries in the CALIPSO cache. Returns zero on * success and negative values on failure. * */ void calipso_cache_invalidate(void) { const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ops->cache_invalidate(); } /** * calipso_cache_add - Add an entry to the CALIPSO cache * @calipso_ptr: the CALIPSO option * @secattr: the packet's security attributes * * Description: * Add a new entry into the CALIPSO label mapping cache. * Returns zero on success, negative values on failure. * */ int calipso_cache_add(const unsigned char *calipso_ptr, const struct netlbl_lsm_secattr *secattr) { int ret_val = -ENOMSG; const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); if (ops) ret_val = ops->cache_add(calipso_ptr, secattr); return ret_val; }
linux-master
net/netlabel/netlabel_calipso.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NetLabel CIPSO/IPv4 Support * * This file defines the CIPSO/IPv4 functions for the NetLabel system. The * NetLabel system manages static and dynamic label mappings for network * protocols such as CIPSO and RIPSO. * * Author: Paul Moore <[email protected]> */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 */ #include <linux/types.h> #include <linux/socket.h> #include <linux/string.h> #include <linux/skbuff.h> #include <linux/audit.h> #include <linux/slab.h> #include <net/sock.h> #include <net/netlink.h> #include <net/genetlink.h> #include <net/netlabel.h> #include <net/cipso_ipv4.h> #include <linux/atomic.h> #include "netlabel_user.h" #include "netlabel_cipso_v4.h" #include "netlabel_mgmt.h" #include "netlabel_domainhash.h" /* Argument struct for cipso_v4_doi_walk() */ struct netlbl_cipsov4_doiwalk_arg { struct netlink_callback *nl_cb; struct sk_buff *skb; u32 seq; }; /* Argument struct for netlbl_domhsh_walk() */ struct netlbl_domhsh_walk_arg { struct netlbl_audit *audit_info; u32 doi; }; /* NetLabel Generic NETLINK CIPSOv4 family */ static struct genl_family netlbl_cipsov4_gnl_family; /* NetLabel Netlink attribute policy */ static const struct nla_policy netlbl_cipsov4_genl_policy[NLBL_CIPSOV4_A_MAX + 1] = { [NLBL_CIPSOV4_A_DOI] = { .type = NLA_U32 }, [NLBL_CIPSOV4_A_MTYPE] = { .type = NLA_U32 }, [NLBL_CIPSOV4_A_TAG] = { .type = NLA_U8 }, [NLBL_CIPSOV4_A_TAGLST] = { .type = NLA_NESTED }, [NLBL_CIPSOV4_A_MLSLVLLOC] = { .type = NLA_U32 }, [NLBL_CIPSOV4_A_MLSLVLREM] = { .type = NLA_U32 }, [NLBL_CIPSOV4_A_MLSLVL] = { .type = NLA_NESTED }, [NLBL_CIPSOV4_A_MLSLVLLST] = { .type = NLA_NESTED }, [NLBL_CIPSOV4_A_MLSCATLOC] = { .type = NLA_U32 }, [NLBL_CIPSOV4_A_MLSCATREM] = { .type = NLA_U32 }, [NLBL_CIPSOV4_A_MLSCAT] = { .type = NLA_NESTED }, [NLBL_CIPSOV4_A_MLSCATLST] = { .type = NLA_NESTED }, }; /* * Helper Functions */ /** * netlbl_cipsov4_add_common - Parse the common sections of a ADD message * @info: the Generic NETLINK info block * @doi_def: the CIPSO V4 DOI definition * * Description: * Parse the common sections of a ADD message and fill in the related values * in @doi_def. Returns zero on success, negative values on failure. * */ static int netlbl_cipsov4_add_common(struct genl_info *info, struct cipso_v4_doi *doi_def) { struct nlattr *nla; int nla_rem; u32 iter = 0; doi_def->doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]); if (nla_validate_nested_deprecated(info->attrs[NLBL_CIPSOV4_A_TAGLST], NLBL_CIPSOV4_A_MAX, netlbl_cipsov4_genl_policy, NULL) != 0) return -EINVAL; nla_for_each_nested(nla, info->attrs[NLBL_CIPSOV4_A_TAGLST], nla_rem) if (nla_type(nla) == NLBL_CIPSOV4_A_TAG) { if (iter >= CIPSO_V4_TAG_MAXCNT) return -EINVAL; doi_def->tags[iter++] = nla_get_u8(nla); } while (iter < CIPSO_V4_TAG_MAXCNT) doi_def->tags[iter++] = CIPSO_V4_TAG_INVALID; return 0; } /* * NetLabel Command Handlers */ /** * netlbl_cipsov4_add_std - Adds a CIPSO V4 DOI definition * @info: the Generic NETLINK info block * @audit_info: NetLabel audit information * * Description: * Create a new CIPSO_V4_MAP_TRANS DOI definition based on the given ADD * message and add it to the CIPSO V4 engine. Return zero on success and * non-zero on error. * */ static int netlbl_cipsov4_add_std(struct genl_info *info, struct netlbl_audit *audit_info) { int ret_val = -EINVAL; struct cipso_v4_doi *doi_def = NULL; struct nlattr *nla_a; struct nlattr *nla_b; int nla_a_rem; int nla_b_rem; u32 iter; if (!info->attrs[NLBL_CIPSOV4_A_TAGLST] || !info->attrs[NLBL_CIPSOV4_A_MLSLVLLST]) return -EINVAL; if (nla_validate_nested_deprecated(info->attrs[NLBL_CIPSOV4_A_MLSLVLLST], NLBL_CIPSOV4_A_MAX, netlbl_cipsov4_genl_policy, NULL) != 0) return -EINVAL; doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL); if (doi_def == NULL) return -ENOMEM; doi_def->map.std = kzalloc(sizeof(*doi_def->map.std), GFP_KERNEL); if (doi_def->map.std == NULL) { kfree(doi_def); return -ENOMEM; } doi_def->type = CIPSO_V4_MAP_TRANS; ret_val = netlbl_cipsov4_add_common(info, doi_def); if (ret_val != 0) goto add_std_failure; ret_val = -EINVAL; nla_for_each_nested(nla_a, info->attrs[NLBL_CIPSOV4_A_MLSLVLLST], nla_a_rem) if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSLVL) { if (nla_validate_nested_deprecated(nla_a, NLBL_CIPSOV4_A_MAX, netlbl_cipsov4_genl_policy, NULL) != 0) goto add_std_failure; nla_for_each_nested(nla_b, nla_a, nla_b_rem) switch (nla_type(nla_b)) { case NLBL_CIPSOV4_A_MLSLVLLOC: if (nla_get_u32(nla_b) > CIPSO_V4_MAX_LOC_LVLS) goto add_std_failure; if (nla_get_u32(nla_b) >= doi_def->map.std->lvl.local_size) doi_def->map.std->lvl.local_size = nla_get_u32(nla_b) + 1; break; case NLBL_CIPSOV4_A_MLSLVLREM: if (nla_get_u32(nla_b) > CIPSO_V4_MAX_REM_LVLS) goto add_std_failure; if (nla_get_u32(nla_b) >= doi_def->map.std->lvl.cipso_size) doi_def->map.std->lvl.cipso_size = nla_get_u32(nla_b) + 1; break; } } doi_def->map.std->lvl.local = kcalloc(doi_def->map.std->lvl.local_size, sizeof(u32), GFP_KERNEL | __GFP_NOWARN); if (doi_def->map.std->lvl.local == NULL) { ret_val = -ENOMEM; goto add_std_failure; } doi_def->map.std->lvl.cipso = kcalloc(doi_def->map.std->lvl.cipso_size, sizeof(u32), GFP_KERNEL | __GFP_NOWARN); if (doi_def->map.std->lvl.cipso == NULL) { ret_val = -ENOMEM; goto add_std_failure; } for (iter = 0; iter < doi_def->map.std->lvl.local_size; iter++) doi_def->map.std->lvl.local[iter] = CIPSO_V4_INV_LVL; for (iter = 0; iter < doi_def->map.std->lvl.cipso_size; iter++) doi_def->map.std->lvl.cipso[iter] = CIPSO_V4_INV_LVL; nla_for_each_nested(nla_a, info->attrs[NLBL_CIPSOV4_A_MLSLVLLST], nla_a_rem) if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSLVL) { struct nlattr *lvl_loc; struct nlattr *lvl_rem; lvl_loc = nla_find_nested(nla_a, NLBL_CIPSOV4_A_MLSLVLLOC); lvl_rem = nla_find_nested(nla_a, NLBL_CIPSOV4_A_MLSLVLREM); if (lvl_loc == NULL || lvl_rem == NULL) goto add_std_failure; doi_def->map.std->lvl.local[nla_get_u32(lvl_loc)] = nla_get_u32(lvl_rem); doi_def->map.std->lvl.cipso[nla_get_u32(lvl_rem)] = nla_get_u32(lvl_loc); } if (info->attrs[NLBL_CIPSOV4_A_MLSCATLST]) { if (nla_validate_nested_deprecated(info->attrs[NLBL_CIPSOV4_A_MLSCATLST], NLBL_CIPSOV4_A_MAX, netlbl_cipsov4_genl_policy, NULL) != 0) goto add_std_failure; nla_for_each_nested(nla_a, info->attrs[NLBL_CIPSOV4_A_MLSCATLST], nla_a_rem) if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSCAT) { if (nla_validate_nested_deprecated(nla_a, NLBL_CIPSOV4_A_MAX, netlbl_cipsov4_genl_policy, NULL) != 0) goto add_std_failure; nla_for_each_nested(nla_b, nla_a, nla_b_rem) switch (nla_type(nla_b)) { case NLBL_CIPSOV4_A_MLSCATLOC: if (nla_get_u32(nla_b) > CIPSO_V4_MAX_LOC_CATS) goto add_std_failure; if (nla_get_u32(nla_b) >= doi_def->map.std->cat.local_size) doi_def->map.std->cat.local_size = nla_get_u32(nla_b) + 1; break; case NLBL_CIPSOV4_A_MLSCATREM: if (nla_get_u32(nla_b) > CIPSO_V4_MAX_REM_CATS) goto add_std_failure; if (nla_get_u32(nla_b) >= doi_def->map.std->cat.cipso_size) doi_def->map.std->cat.cipso_size = nla_get_u32(nla_b) + 1; break; } } doi_def->map.std->cat.local = kcalloc( doi_def->map.std->cat.local_size, sizeof(u32), GFP_KERNEL | __GFP_NOWARN); if (doi_def->map.std->cat.local == NULL) { ret_val = -ENOMEM; goto add_std_failure; } doi_def->map.std->cat.cipso = kcalloc( doi_def->map.std->cat.cipso_size, sizeof(u32), GFP_KERNEL | __GFP_NOWARN); if (doi_def->map.std->cat.cipso == NULL) { ret_val = -ENOMEM; goto add_std_failure; } for (iter = 0; iter < doi_def->map.std->cat.local_size; iter++) doi_def->map.std->cat.local[iter] = CIPSO_V4_INV_CAT; for (iter = 0; iter < doi_def->map.std->cat.cipso_size; iter++) doi_def->map.std->cat.cipso[iter] = CIPSO_V4_INV_CAT; nla_for_each_nested(nla_a, info->attrs[NLBL_CIPSOV4_A_MLSCATLST], nla_a_rem) if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSCAT) { struct nlattr *cat_loc; struct nlattr *cat_rem; cat_loc = nla_find_nested(nla_a, NLBL_CIPSOV4_A_MLSCATLOC); cat_rem = nla_find_nested(nla_a, NLBL_CIPSOV4_A_MLSCATREM); if (cat_loc == NULL || cat_rem == NULL) goto add_std_failure; doi_def->map.std->cat.local[ nla_get_u32(cat_loc)] = nla_get_u32(cat_rem); doi_def->map.std->cat.cipso[ nla_get_u32(cat_rem)] = nla_get_u32(cat_loc); } } ret_val = cipso_v4_doi_add(doi_def, audit_info); if (ret_val != 0) goto add_std_failure; return 0; add_std_failure: cipso_v4_doi_free(doi_def); return ret_val; } /** * netlbl_cipsov4_add_pass - Adds a CIPSO V4 DOI definition * @info: the Generic NETLINK info block * @audit_info: NetLabel audit information * * Description: * Create a new CIPSO_V4_MAP_PASS DOI definition based on the given ADD message * and add it to the CIPSO V4 engine. Return zero on success and non-zero on * error. * */ static int netlbl_cipsov4_add_pass(struct genl_info *info, struct netlbl_audit *audit_info) { int ret_val; struct cipso_v4_doi *doi_def = NULL; if (!info->attrs[NLBL_CIPSOV4_A_TAGLST]) return -EINVAL; doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL); if (doi_def == NULL) return -ENOMEM; doi_def->type = CIPSO_V4_MAP_PASS; ret_val = netlbl_cipsov4_add_common(info, doi_def); if (ret_val != 0) goto add_pass_failure; ret_val = cipso_v4_doi_add(doi_def, audit_info); if (ret_val != 0) goto add_pass_failure; return 0; add_pass_failure: cipso_v4_doi_free(doi_def); return ret_val; } /** * netlbl_cipsov4_add_local - Adds a CIPSO V4 DOI definition * @info: the Generic NETLINK info block * @audit_info: NetLabel audit information * * Description: * Create a new CIPSO_V4_MAP_LOCAL DOI definition based on the given ADD * message and add it to the CIPSO V4 engine. Return zero on success and * non-zero on error. * */ static int netlbl_cipsov4_add_local(struct genl_info *info, struct netlbl_audit *audit_info) { int ret_val; struct cipso_v4_doi *doi_def = NULL; if (!info->attrs[NLBL_CIPSOV4_A_TAGLST]) return -EINVAL; doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL); if (doi_def == NULL) return -ENOMEM; doi_def->type = CIPSO_V4_MAP_LOCAL; ret_val = netlbl_cipsov4_add_common(info, doi_def); if (ret_val != 0) goto add_local_failure; ret_val = cipso_v4_doi_add(doi_def, audit_info); if (ret_val != 0) goto add_local_failure; return 0; add_local_failure: cipso_v4_doi_free(doi_def); return ret_val; } /** * netlbl_cipsov4_add - Handle an ADD message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Create a new DOI definition based on the given ADD message and add it to the * CIPSO V4 engine. Returns zero on success, negative values on failure. * */ static int netlbl_cipsov4_add(struct sk_buff *skb, struct genl_info *info) { int ret_val = -EINVAL; struct netlbl_audit audit_info; if (!info->attrs[NLBL_CIPSOV4_A_DOI] || !info->attrs[NLBL_CIPSOV4_A_MTYPE]) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); switch (nla_get_u32(info->attrs[NLBL_CIPSOV4_A_MTYPE])) { case CIPSO_V4_MAP_TRANS: ret_val = netlbl_cipsov4_add_std(info, &audit_info); break; case CIPSO_V4_MAP_PASS: ret_val = netlbl_cipsov4_add_pass(info, &audit_info); break; case CIPSO_V4_MAP_LOCAL: ret_val = netlbl_cipsov4_add_local(info, &audit_info); break; } if (ret_val == 0) atomic_inc(&netlabel_mgmt_protocount); return ret_val; } /** * netlbl_cipsov4_list - Handle a LIST message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated LIST message and respond accordingly. While the * response message generated by the kernel is straightforward, determining * before hand the size of the buffer to allocate is not (we have to generate * the message to know the size). In order to keep this function sane what we * do is allocate a buffer of NLMSG_GOODSIZE and try to fit the response in * that size, if we fail then we restart with a larger buffer and try again. * We continue in this manner until we hit a limit of failed attempts then we * give up and just send an error message. Returns zero on success and * negative values on error. * */ static int netlbl_cipsov4_list(struct sk_buff *skb, struct genl_info *info) { int ret_val; struct sk_buff *ans_skb = NULL; u32 nlsze_mult = 1; void *data; u32 doi; struct nlattr *nla_a; struct nlattr *nla_b; struct cipso_v4_doi *doi_def; u32 iter; if (!info->attrs[NLBL_CIPSOV4_A_DOI]) { ret_val = -EINVAL; goto list_failure; } list_start: ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE * nlsze_mult, GFP_KERNEL); if (ans_skb == NULL) { ret_val = -ENOMEM; goto list_failure; } data = genlmsg_put_reply(ans_skb, info, &netlbl_cipsov4_gnl_family, 0, NLBL_CIPSOV4_C_LIST); if (data == NULL) { ret_val = -ENOMEM; goto list_failure; } doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]); rcu_read_lock(); doi_def = cipso_v4_doi_getdef(doi); if (doi_def == NULL) { ret_val = -EINVAL; goto list_failure_lock; } ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MTYPE, doi_def->type); if (ret_val != 0) goto list_failure_lock; nla_a = nla_nest_start_noflag(ans_skb, NLBL_CIPSOV4_A_TAGLST); if (nla_a == NULL) { ret_val = -ENOMEM; goto list_failure_lock; } for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT && doi_def->tags[iter] != CIPSO_V4_TAG_INVALID; iter++) { ret_val = nla_put_u8(ans_skb, NLBL_CIPSOV4_A_TAG, doi_def->tags[iter]); if (ret_val != 0) goto list_failure_lock; } nla_nest_end(ans_skb, nla_a); switch (doi_def->type) { case CIPSO_V4_MAP_TRANS: nla_a = nla_nest_start_noflag(ans_skb, NLBL_CIPSOV4_A_MLSLVLLST); if (nla_a == NULL) { ret_val = -ENOMEM; goto list_failure_lock; } for (iter = 0; iter < doi_def->map.std->lvl.local_size; iter++) { if (doi_def->map.std->lvl.local[iter] == CIPSO_V4_INV_LVL) continue; nla_b = nla_nest_start_noflag(ans_skb, NLBL_CIPSOV4_A_MLSLVL); if (nla_b == NULL) { ret_val = -ENOMEM; goto list_retry; } ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MLSLVLLOC, iter); if (ret_val != 0) goto list_retry; ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MLSLVLREM, doi_def->map.std->lvl.local[iter]); if (ret_val != 0) goto list_retry; nla_nest_end(ans_skb, nla_b); } nla_nest_end(ans_skb, nla_a); nla_a = nla_nest_start_noflag(ans_skb, NLBL_CIPSOV4_A_MLSCATLST); if (nla_a == NULL) { ret_val = -ENOMEM; goto list_retry; } for (iter = 0; iter < doi_def->map.std->cat.local_size; iter++) { if (doi_def->map.std->cat.local[iter] == CIPSO_V4_INV_CAT) continue; nla_b = nla_nest_start_noflag(ans_skb, NLBL_CIPSOV4_A_MLSCAT); if (nla_b == NULL) { ret_val = -ENOMEM; goto list_retry; } ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MLSCATLOC, iter); if (ret_val != 0) goto list_retry; ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MLSCATREM, doi_def->map.std->cat.local[iter]); if (ret_val != 0) goto list_retry; nla_nest_end(ans_skb, nla_b); } nla_nest_end(ans_skb, nla_a); break; } cipso_v4_doi_putdef(doi_def); rcu_read_unlock(); genlmsg_end(ans_skb, data); return genlmsg_reply(ans_skb, info); list_retry: /* XXX - this limit is a guesstimate */ if (nlsze_mult < 4) { cipso_v4_doi_putdef(doi_def); rcu_read_unlock(); kfree_skb(ans_skb); nlsze_mult *= 2; goto list_start; } list_failure_lock: cipso_v4_doi_putdef(doi_def); rcu_read_unlock(); list_failure: kfree_skb(ans_skb); return ret_val; } /** * netlbl_cipsov4_listall_cb - cipso_v4_doi_walk() callback for LISTALL * @doi_def: the CIPSOv4 DOI definition * @arg: the netlbl_cipsov4_doiwalk_arg structure * * Description: * This function is designed to be used as a callback to the * cipso_v4_doi_walk() function for use in generating a response for a LISTALL * message. Returns the size of the message on success, negative values on * failure. * */ static int netlbl_cipsov4_listall_cb(struct cipso_v4_doi *doi_def, void *arg) { int ret_val = -ENOMEM; struct netlbl_cipsov4_doiwalk_arg *cb_arg = arg; void *data; data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid, cb_arg->seq, &netlbl_cipsov4_gnl_family, NLM_F_MULTI, NLBL_CIPSOV4_C_LISTALL); if (data == NULL) goto listall_cb_failure; ret_val = nla_put_u32(cb_arg->skb, NLBL_CIPSOV4_A_DOI, doi_def->doi); if (ret_val != 0) goto listall_cb_failure; ret_val = nla_put_u32(cb_arg->skb, NLBL_CIPSOV4_A_MTYPE, doi_def->type); if (ret_val != 0) goto listall_cb_failure; genlmsg_end(cb_arg->skb, data); return 0; listall_cb_failure: genlmsg_cancel(cb_arg->skb, data); return ret_val; } /** * netlbl_cipsov4_listall - Handle a LISTALL message * @skb: the NETLINK buffer * @cb: the NETLINK callback * * Description: * Process a user generated LISTALL message and respond accordingly. Returns * zero on success and negative values on error. * */ static int netlbl_cipsov4_listall(struct sk_buff *skb, struct netlink_callback *cb) { struct netlbl_cipsov4_doiwalk_arg cb_arg; u32 doi_skip = cb->args[0]; cb_arg.nl_cb = cb; cb_arg.skb = skb; cb_arg.seq = cb->nlh->nlmsg_seq; cipso_v4_doi_walk(&doi_skip, netlbl_cipsov4_listall_cb, &cb_arg); cb->args[0] = doi_skip; return skb->len; } /** * netlbl_cipsov4_remove_cb - netlbl_cipsov4_remove() callback for REMOVE * @entry: LSM domain mapping entry * @arg: the netlbl_domhsh_walk_arg structure * * Description: * This function is intended for use by netlbl_cipsov4_remove() as the callback * for the netlbl_domhsh_walk() function; it removes LSM domain map entries * which are associated with the CIPSO DOI specified in @arg. Returns zero on * success, negative values on failure. * */ static int netlbl_cipsov4_remove_cb(struct netlbl_dom_map *entry, void *arg) { struct netlbl_domhsh_walk_arg *cb_arg = arg; if (entry->def.type == NETLBL_NLTYPE_CIPSOV4 && entry->def.cipso->doi == cb_arg->doi) return netlbl_domhsh_remove_entry(entry, cb_arg->audit_info); return 0; } /** * netlbl_cipsov4_remove - Handle a REMOVE message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated REMOVE message and respond accordingly. Returns * zero on success, negative values on failure. * */ static int netlbl_cipsov4_remove(struct sk_buff *skb, struct genl_info *info) { int ret_val = -EINVAL; struct netlbl_domhsh_walk_arg cb_arg; struct netlbl_audit audit_info; u32 skip_bkt = 0; u32 skip_chain = 0; if (!info->attrs[NLBL_CIPSOV4_A_DOI]) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); cb_arg.doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]); cb_arg.audit_info = &audit_info; ret_val = netlbl_domhsh_walk(&skip_bkt, &skip_chain, netlbl_cipsov4_remove_cb, &cb_arg); if (ret_val == 0 || ret_val == -ENOENT) { ret_val = cipso_v4_doi_remove(cb_arg.doi, &audit_info); if (ret_val == 0) atomic_dec(&netlabel_mgmt_protocount); } return ret_val; } /* * NetLabel Generic NETLINK Command Definitions */ static const struct genl_small_ops netlbl_cipsov4_ops[] = { { .cmd = NLBL_CIPSOV4_C_ADD, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_cipsov4_add, .dumpit = NULL, }, { .cmd = NLBL_CIPSOV4_C_REMOVE, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_cipsov4_remove, .dumpit = NULL, }, { .cmd = NLBL_CIPSOV4_C_LIST, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = netlbl_cipsov4_list, .dumpit = NULL, }, { .cmd = NLBL_CIPSOV4_C_LISTALL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = NULL, .dumpit = netlbl_cipsov4_listall, }, }; static struct genl_family netlbl_cipsov4_gnl_family __ro_after_init = { .hdrsize = 0, .name = NETLBL_NLTYPE_CIPSOV4_NAME, .version = NETLBL_PROTO_VERSION, .maxattr = NLBL_CIPSOV4_A_MAX, .policy = netlbl_cipsov4_genl_policy, .module = THIS_MODULE, .small_ops = netlbl_cipsov4_ops, .n_small_ops = ARRAY_SIZE(netlbl_cipsov4_ops), .resv_start_op = NLBL_CIPSOV4_C_LISTALL + 1, }; /* * NetLabel Generic NETLINK Protocol Functions */ /** * netlbl_cipsov4_genl_init - Register the CIPSOv4 NetLabel component * * Description: * Register the CIPSOv4 packet NetLabel component with the Generic NETLINK * mechanism. Returns zero on success, negative values on failure. * */ int __init netlbl_cipsov4_genl_init(void) { return genl_register_family(&netlbl_cipsov4_gnl_family); }
linux-master
net/netlabel/netlabel_cipso_v4.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NetLabel Management Support * * This file defines the management functions for the NetLabel system. The * NetLabel system manages static and dynamic label mappings for network * protocols such as CIPSO and RIPSO. * * Author: Paul Moore <[email protected]> */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 */ #include <linux/types.h> #include <linux/socket.h> #include <linux/string.h> #include <linux/skbuff.h> #include <linux/in.h> #include <linux/in6.h> #include <linux/slab.h> #include <net/sock.h> #include <net/netlink.h> #include <net/genetlink.h> #include <net/ip.h> #include <net/ipv6.h> #include <net/netlabel.h> #include <net/cipso_ipv4.h> #include <net/calipso.h> #include <linux/atomic.h> #include "netlabel_calipso.h" #include "netlabel_domainhash.h" #include "netlabel_user.h" #include "netlabel_mgmt.h" /* NetLabel configured protocol counter */ atomic_t netlabel_mgmt_protocount = ATOMIC_INIT(0); /* Argument struct for netlbl_domhsh_walk() */ struct netlbl_domhsh_walk_arg { struct netlink_callback *nl_cb; struct sk_buff *skb; u32 seq; }; /* NetLabel Generic NETLINK CIPSOv4 family */ static struct genl_family netlbl_mgmt_gnl_family; /* NetLabel Netlink attribute policy */ static const struct nla_policy netlbl_mgmt_genl_policy[NLBL_MGMT_A_MAX + 1] = { [NLBL_MGMT_A_DOMAIN] = { .type = NLA_NUL_STRING }, [NLBL_MGMT_A_PROTOCOL] = { .type = NLA_U32 }, [NLBL_MGMT_A_VERSION] = { .type = NLA_U32 }, [NLBL_MGMT_A_CV4DOI] = { .type = NLA_U32 }, [NLBL_MGMT_A_FAMILY] = { .type = NLA_U16 }, [NLBL_MGMT_A_CLPDOI] = { .type = NLA_U32 }, }; /* * Helper Functions */ /** * netlbl_mgmt_add_common - Handle an ADD message * @info: the Generic NETLINK info block * @audit_info: NetLabel audit information * * Description: * Helper function for the ADD and ADDDEF messages to add the domain mappings * from the message to the hash table. See netlabel.h for a description of the * message format. Returns zero on success, negative values on failure. * */ static int netlbl_mgmt_add_common(struct genl_info *info, struct netlbl_audit *audit_info) { void *pmap = NULL; int ret_val = -EINVAL; struct netlbl_domaddr_map *addrmap = NULL; struct cipso_v4_doi *cipsov4 = NULL; #if IS_ENABLED(CONFIG_IPV6) struct calipso_doi *calipso = NULL; #endif u32 tmp_val; struct netlbl_dom_map *entry = kzalloc(sizeof(*entry), GFP_KERNEL); if (!entry) return -ENOMEM; entry->def.type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]); if (info->attrs[NLBL_MGMT_A_DOMAIN]) { size_t tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]); entry->domain = kmalloc(tmp_size, GFP_KERNEL); if (entry->domain == NULL) { ret_val = -ENOMEM; goto add_free_entry; } nla_strscpy(entry->domain, info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size); } /* NOTE: internally we allow/use a entry->def.type value of * NETLBL_NLTYPE_ADDRSELECT but we don't currently allow users * to pass that as a protocol value because we need to know the * "real" protocol */ switch (entry->def.type) { case NETLBL_NLTYPE_UNLABELED: if (info->attrs[NLBL_MGMT_A_FAMILY]) entry->family = nla_get_u16(info->attrs[NLBL_MGMT_A_FAMILY]); else entry->family = AF_UNSPEC; break; case NETLBL_NLTYPE_CIPSOV4: if (!info->attrs[NLBL_MGMT_A_CV4DOI]) goto add_free_domain; tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]); cipsov4 = cipso_v4_doi_getdef(tmp_val); if (cipsov4 == NULL) goto add_free_domain; entry->family = AF_INET; entry->def.cipso = cipsov4; break; #if IS_ENABLED(CONFIG_IPV6) case NETLBL_NLTYPE_CALIPSO: if (!info->attrs[NLBL_MGMT_A_CLPDOI]) goto add_free_domain; tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CLPDOI]); calipso = calipso_doi_getdef(tmp_val); if (calipso == NULL) goto add_free_domain; entry->family = AF_INET6; entry->def.calipso = calipso; break; #endif /* IPv6 */ default: goto add_free_domain; } if ((entry->family == AF_INET && info->attrs[NLBL_MGMT_A_IPV6ADDR]) || (entry->family == AF_INET6 && info->attrs[NLBL_MGMT_A_IPV4ADDR])) goto add_doi_put_def; if (info->attrs[NLBL_MGMT_A_IPV4ADDR]) { struct in_addr *addr; struct in_addr *mask; struct netlbl_domaddr4_map *map; addrmap = kzalloc(sizeof(*addrmap), GFP_KERNEL); if (addrmap == NULL) { ret_val = -ENOMEM; goto add_doi_put_def; } INIT_LIST_HEAD(&addrmap->list4); INIT_LIST_HEAD(&addrmap->list6); if (nla_len(info->attrs[NLBL_MGMT_A_IPV4ADDR]) != sizeof(struct in_addr)) { ret_val = -EINVAL; goto add_free_addrmap; } if (nla_len(info->attrs[NLBL_MGMT_A_IPV4MASK]) != sizeof(struct in_addr)) { ret_val = -EINVAL; goto add_free_addrmap; } addr = nla_data(info->attrs[NLBL_MGMT_A_IPV4ADDR]); mask = nla_data(info->attrs[NLBL_MGMT_A_IPV4MASK]); map = kzalloc(sizeof(*map), GFP_KERNEL); if (map == NULL) { ret_val = -ENOMEM; goto add_free_addrmap; } pmap = map; map->list.addr = addr->s_addr & mask->s_addr; map->list.mask = mask->s_addr; map->list.valid = 1; map->def.type = entry->def.type; if (cipsov4) map->def.cipso = cipsov4; ret_val = netlbl_af4list_add(&map->list, &addrmap->list4); if (ret_val != 0) goto add_free_map; entry->family = AF_INET; entry->def.type = NETLBL_NLTYPE_ADDRSELECT; entry->def.addrsel = addrmap; #if IS_ENABLED(CONFIG_IPV6) } else if (info->attrs[NLBL_MGMT_A_IPV6ADDR]) { struct in6_addr *addr; struct in6_addr *mask; struct netlbl_domaddr6_map *map; addrmap = kzalloc(sizeof(*addrmap), GFP_KERNEL); if (addrmap == NULL) { ret_val = -ENOMEM; goto add_doi_put_def; } INIT_LIST_HEAD(&addrmap->list4); INIT_LIST_HEAD(&addrmap->list6); if (nla_len(info->attrs[NLBL_MGMT_A_IPV6ADDR]) != sizeof(struct in6_addr)) { ret_val = -EINVAL; goto add_free_addrmap; } if (nla_len(info->attrs[NLBL_MGMT_A_IPV6MASK]) != sizeof(struct in6_addr)) { ret_val = -EINVAL; goto add_free_addrmap; } addr = nla_data(info->attrs[NLBL_MGMT_A_IPV6ADDR]); mask = nla_data(info->attrs[NLBL_MGMT_A_IPV6MASK]); map = kzalloc(sizeof(*map), GFP_KERNEL); if (map == NULL) { ret_val = -ENOMEM; goto add_free_addrmap; } pmap = map; map->list.addr = *addr; map->list.addr.s6_addr32[0] &= mask->s6_addr32[0]; map->list.addr.s6_addr32[1] &= mask->s6_addr32[1]; map->list.addr.s6_addr32[2] &= mask->s6_addr32[2]; map->list.addr.s6_addr32[3] &= mask->s6_addr32[3]; map->list.mask = *mask; map->list.valid = 1; map->def.type = entry->def.type; if (calipso) map->def.calipso = calipso; ret_val = netlbl_af6list_add(&map->list, &addrmap->list6); if (ret_val != 0) goto add_free_map; entry->family = AF_INET6; entry->def.type = NETLBL_NLTYPE_ADDRSELECT; entry->def.addrsel = addrmap; #endif /* IPv6 */ } ret_val = netlbl_domhsh_add(entry, audit_info); if (ret_val != 0) goto add_free_map; return 0; add_free_map: kfree(pmap); add_free_addrmap: kfree(addrmap); add_doi_put_def: cipso_v4_doi_putdef(cipsov4); #if IS_ENABLED(CONFIG_IPV6) calipso_doi_putdef(calipso); #endif add_free_domain: kfree(entry->domain); add_free_entry: kfree(entry); return ret_val; } /** * netlbl_mgmt_listentry - List a NetLabel/LSM domain map entry * @skb: the NETLINK buffer * @entry: the map entry * * Description: * This function is a helper function used by the LISTALL and LISTDEF command * handlers. The caller is responsible for ensuring that the RCU read lock * is held. Returns zero on success, negative values on failure. * */ static int netlbl_mgmt_listentry(struct sk_buff *skb, struct netlbl_dom_map *entry) { int ret_val = 0; struct nlattr *nla_a; struct nlattr *nla_b; struct netlbl_af4list *iter4; #if IS_ENABLED(CONFIG_IPV6) struct netlbl_af6list *iter6; #endif if (entry->domain != NULL) { ret_val = nla_put_string(skb, NLBL_MGMT_A_DOMAIN, entry->domain); if (ret_val != 0) return ret_val; } ret_val = nla_put_u16(skb, NLBL_MGMT_A_FAMILY, entry->family); if (ret_val != 0) return ret_val; switch (entry->def.type) { case NETLBL_NLTYPE_ADDRSELECT: nla_a = nla_nest_start_noflag(skb, NLBL_MGMT_A_SELECTORLIST); if (nla_a == NULL) return -ENOMEM; netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) { struct netlbl_domaddr4_map *map4; struct in_addr addr_struct; nla_b = nla_nest_start_noflag(skb, NLBL_MGMT_A_ADDRSELECTOR); if (nla_b == NULL) return -ENOMEM; addr_struct.s_addr = iter4->addr; ret_val = nla_put_in_addr(skb, NLBL_MGMT_A_IPV4ADDR, addr_struct.s_addr); if (ret_val != 0) return ret_val; addr_struct.s_addr = iter4->mask; ret_val = nla_put_in_addr(skb, NLBL_MGMT_A_IPV4MASK, addr_struct.s_addr); if (ret_val != 0) return ret_val; map4 = netlbl_domhsh_addr4_entry(iter4); ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, map4->def.type); if (ret_val != 0) return ret_val; switch (map4->def.type) { case NETLBL_NLTYPE_CIPSOV4: ret_val = nla_put_u32(skb, NLBL_MGMT_A_CV4DOI, map4->def.cipso->doi); if (ret_val != 0) return ret_val; break; } nla_nest_end(skb, nla_b); } #if IS_ENABLED(CONFIG_IPV6) netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) { struct netlbl_domaddr6_map *map6; nla_b = nla_nest_start_noflag(skb, NLBL_MGMT_A_ADDRSELECTOR); if (nla_b == NULL) return -ENOMEM; ret_val = nla_put_in6_addr(skb, NLBL_MGMT_A_IPV6ADDR, &iter6->addr); if (ret_val != 0) return ret_val; ret_val = nla_put_in6_addr(skb, NLBL_MGMT_A_IPV6MASK, &iter6->mask); if (ret_val != 0) return ret_val; map6 = netlbl_domhsh_addr6_entry(iter6); ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, map6->def.type); if (ret_val != 0) return ret_val; switch (map6->def.type) { case NETLBL_NLTYPE_CALIPSO: ret_val = nla_put_u32(skb, NLBL_MGMT_A_CLPDOI, map6->def.calipso->doi); if (ret_val != 0) return ret_val; break; } nla_nest_end(skb, nla_b); } #endif /* IPv6 */ nla_nest_end(skb, nla_a); break; case NETLBL_NLTYPE_UNLABELED: ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, entry->def.type); break; case NETLBL_NLTYPE_CIPSOV4: ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, entry->def.type); if (ret_val != 0) return ret_val; ret_val = nla_put_u32(skb, NLBL_MGMT_A_CV4DOI, entry->def.cipso->doi); break; case NETLBL_NLTYPE_CALIPSO: ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, entry->def.type); if (ret_val != 0) return ret_val; ret_val = nla_put_u32(skb, NLBL_MGMT_A_CLPDOI, entry->def.calipso->doi); break; } return ret_val; } /* * NetLabel Command Handlers */ /** * netlbl_mgmt_add - Handle an ADD message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated ADD message and add the domains from the message * to the hash table. See netlabel.h for a description of the message format. * Returns zero on success, negative values on failure. * */ static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info) { struct netlbl_audit audit_info; if ((!info->attrs[NLBL_MGMT_A_DOMAIN]) || (!info->attrs[NLBL_MGMT_A_PROTOCOL]) || (info->attrs[NLBL_MGMT_A_IPV4ADDR] && info->attrs[NLBL_MGMT_A_IPV6ADDR]) || (info->attrs[NLBL_MGMT_A_IPV4MASK] && info->attrs[NLBL_MGMT_A_IPV6MASK]) || ((info->attrs[NLBL_MGMT_A_IPV4ADDR] != NULL) ^ (info->attrs[NLBL_MGMT_A_IPV4MASK] != NULL)) || ((info->attrs[NLBL_MGMT_A_IPV6ADDR] != NULL) ^ (info->attrs[NLBL_MGMT_A_IPV6MASK] != NULL))) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); return netlbl_mgmt_add_common(info, &audit_info); } /** * netlbl_mgmt_remove - Handle a REMOVE message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated REMOVE message and remove the specified domain * mappings. Returns zero on success, negative values on failure. * */ static int netlbl_mgmt_remove(struct sk_buff *skb, struct genl_info *info) { char *domain; struct netlbl_audit audit_info; if (!info->attrs[NLBL_MGMT_A_DOMAIN]) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]); return netlbl_domhsh_remove(domain, AF_UNSPEC, &audit_info); } /** * netlbl_mgmt_listall_cb - netlbl_domhsh_walk() callback for LISTALL * @entry: the domain mapping hash table entry * @arg: the netlbl_domhsh_walk_arg structure * * Description: * This function is designed to be used as a callback to the * netlbl_domhsh_walk() function for use in generating a response for a LISTALL * message. Returns the size of the message on success, negative values on * failure. * */ static int netlbl_mgmt_listall_cb(struct netlbl_dom_map *entry, void *arg) { int ret_val = -ENOMEM; struct netlbl_domhsh_walk_arg *cb_arg = arg; void *data; data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid, cb_arg->seq, &netlbl_mgmt_gnl_family, NLM_F_MULTI, NLBL_MGMT_C_LISTALL); if (data == NULL) goto listall_cb_failure; ret_val = netlbl_mgmt_listentry(cb_arg->skb, entry); if (ret_val != 0) goto listall_cb_failure; cb_arg->seq++; genlmsg_end(cb_arg->skb, data); return 0; listall_cb_failure: genlmsg_cancel(cb_arg->skb, data); return ret_val; } /** * netlbl_mgmt_listall - Handle a LISTALL message * @skb: the NETLINK buffer * @cb: the NETLINK callback * * Description: * Process a user generated LISTALL message and dumps the domain hash table in * a form suitable for use in a kernel generated LISTALL message. Returns zero * on success, negative values on failure. * */ static int netlbl_mgmt_listall(struct sk_buff *skb, struct netlink_callback *cb) { struct netlbl_domhsh_walk_arg cb_arg; u32 skip_bkt = cb->args[0]; u32 skip_chain = cb->args[1]; cb_arg.nl_cb = cb; cb_arg.skb = skb; cb_arg.seq = cb->nlh->nlmsg_seq; netlbl_domhsh_walk(&skip_bkt, &skip_chain, netlbl_mgmt_listall_cb, &cb_arg); cb->args[0] = skip_bkt; cb->args[1] = skip_chain; return skb->len; } /** * netlbl_mgmt_adddef - Handle an ADDDEF message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated ADDDEF message and respond accordingly. Returns * zero on success, negative values on failure. * */ static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info) { struct netlbl_audit audit_info; if ((!info->attrs[NLBL_MGMT_A_PROTOCOL]) || (info->attrs[NLBL_MGMT_A_IPV4ADDR] && info->attrs[NLBL_MGMT_A_IPV6ADDR]) || (info->attrs[NLBL_MGMT_A_IPV4MASK] && info->attrs[NLBL_MGMT_A_IPV6MASK]) || ((info->attrs[NLBL_MGMT_A_IPV4ADDR] != NULL) ^ (info->attrs[NLBL_MGMT_A_IPV4MASK] != NULL)) || ((info->attrs[NLBL_MGMT_A_IPV6ADDR] != NULL) ^ (info->attrs[NLBL_MGMT_A_IPV6MASK] != NULL))) return -EINVAL; netlbl_netlink_auditinfo(&audit_info); return netlbl_mgmt_add_common(info, &audit_info); } /** * netlbl_mgmt_removedef - Handle a REMOVEDEF message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated REMOVEDEF message and remove the default domain * mapping. Returns zero on success, negative values on failure. * */ static int netlbl_mgmt_removedef(struct sk_buff *skb, struct genl_info *info) { struct netlbl_audit audit_info; netlbl_netlink_auditinfo(&audit_info); return netlbl_domhsh_remove_default(AF_UNSPEC, &audit_info); } /** * netlbl_mgmt_listdef - Handle a LISTDEF message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated LISTDEF message and dumps the default domain * mapping in a form suitable for use in a kernel generated LISTDEF message. * Returns zero on success, negative values on failure. * */ static int netlbl_mgmt_listdef(struct sk_buff *skb, struct genl_info *info) { int ret_val = -ENOMEM; struct sk_buff *ans_skb = NULL; void *data; struct netlbl_dom_map *entry; u16 family; if (info->attrs[NLBL_MGMT_A_FAMILY]) family = nla_get_u16(info->attrs[NLBL_MGMT_A_FAMILY]); else family = AF_INET; ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (ans_skb == NULL) return -ENOMEM; data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family, 0, NLBL_MGMT_C_LISTDEF); if (data == NULL) goto listdef_failure; rcu_read_lock(); entry = netlbl_domhsh_getentry(NULL, family); if (entry == NULL) { ret_val = -ENOENT; goto listdef_failure_lock; } ret_val = netlbl_mgmt_listentry(ans_skb, entry); rcu_read_unlock(); if (ret_val != 0) goto listdef_failure; genlmsg_end(ans_skb, data); return genlmsg_reply(ans_skb, info); listdef_failure_lock: rcu_read_unlock(); listdef_failure: kfree_skb(ans_skb); return ret_val; } /** * netlbl_mgmt_protocols_cb - Write an individual PROTOCOL message response * @skb: the skb to write to * @cb: the NETLINK callback * @protocol: the NetLabel protocol to use in the message * * Description: * This function is to be used in conjunction with netlbl_mgmt_protocols() to * answer a application's PROTOCOLS message. Returns the size of the message * on success, negative values on failure. * */ static int netlbl_mgmt_protocols_cb(struct sk_buff *skb, struct netlink_callback *cb, u32 protocol) { int ret_val = -ENOMEM; void *data; data = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, &netlbl_mgmt_gnl_family, NLM_F_MULTI, NLBL_MGMT_C_PROTOCOLS); if (data == NULL) goto protocols_cb_failure; ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol); if (ret_val != 0) goto protocols_cb_failure; genlmsg_end(skb, data); return 0; protocols_cb_failure: genlmsg_cancel(skb, data); return ret_val; } /** * netlbl_mgmt_protocols - Handle a PROTOCOLS message * @skb: the NETLINK buffer * @cb: the NETLINK callback * * Description: * Process a user generated PROTOCOLS message and respond accordingly. * */ static int netlbl_mgmt_protocols(struct sk_buff *skb, struct netlink_callback *cb) { u32 protos_sent = cb->args[0]; if (protos_sent == 0) { if (netlbl_mgmt_protocols_cb(skb, cb, NETLBL_NLTYPE_UNLABELED) < 0) goto protocols_return; protos_sent++; } if (protos_sent == 1) { if (netlbl_mgmt_protocols_cb(skb, cb, NETLBL_NLTYPE_CIPSOV4) < 0) goto protocols_return; protos_sent++; } #if IS_ENABLED(CONFIG_IPV6) if (protos_sent == 2) { if (netlbl_mgmt_protocols_cb(skb, cb, NETLBL_NLTYPE_CALIPSO) < 0) goto protocols_return; protos_sent++; } #endif protocols_return: cb->args[0] = protos_sent; return skb->len; } /** * netlbl_mgmt_version - Handle a VERSION message * @skb: the NETLINK buffer * @info: the Generic NETLINK info block * * Description: * Process a user generated VERSION message and respond accordingly. Returns * zero on success, negative values on failure. * */ static int netlbl_mgmt_version(struct sk_buff *skb, struct genl_info *info) { int ret_val = -ENOMEM; struct sk_buff *ans_skb = NULL; void *data; ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (ans_skb == NULL) return -ENOMEM; data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family, 0, NLBL_MGMT_C_VERSION); if (data == NULL) goto version_failure; ret_val = nla_put_u32(ans_skb, NLBL_MGMT_A_VERSION, NETLBL_PROTO_VERSION); if (ret_val != 0) goto version_failure; genlmsg_end(ans_skb, data); return genlmsg_reply(ans_skb, info); version_failure: kfree_skb(ans_skb); return ret_val; } /* * NetLabel Generic NETLINK Command Definitions */ static const struct genl_small_ops netlbl_mgmt_genl_ops[] = { { .cmd = NLBL_MGMT_C_ADD, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_mgmt_add, .dumpit = NULL, }, { .cmd = NLBL_MGMT_C_REMOVE, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_mgmt_remove, .dumpit = NULL, }, { .cmd = NLBL_MGMT_C_LISTALL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = NULL, .dumpit = netlbl_mgmt_listall, }, { .cmd = NLBL_MGMT_C_ADDDEF, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_mgmt_adddef, .dumpit = NULL, }, { .cmd = NLBL_MGMT_C_REMOVEDEF, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = netlbl_mgmt_removedef, .dumpit = NULL, }, { .cmd = NLBL_MGMT_C_LISTDEF, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = netlbl_mgmt_listdef, .dumpit = NULL, }, { .cmd = NLBL_MGMT_C_PROTOCOLS, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = NULL, .dumpit = netlbl_mgmt_protocols, }, { .cmd = NLBL_MGMT_C_VERSION, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = 0, .doit = netlbl_mgmt_version, .dumpit = NULL, }, }; static struct genl_family netlbl_mgmt_gnl_family __ro_after_init = { .hdrsize = 0, .name = NETLBL_NLTYPE_MGMT_NAME, .version = NETLBL_PROTO_VERSION, .maxattr = NLBL_MGMT_A_MAX, .policy = netlbl_mgmt_genl_policy, .module = THIS_MODULE, .small_ops = netlbl_mgmt_genl_ops, .n_small_ops = ARRAY_SIZE(netlbl_mgmt_genl_ops), .resv_start_op = NLBL_MGMT_C_VERSION + 1, }; /* * NetLabel Generic NETLINK Protocol Functions */ /** * netlbl_mgmt_genl_init - Register the NetLabel management component * * Description: * Register the NetLabel management component with the Generic NETLINK * mechanism. Returns zero on success, negative values on failure. * */ int __init netlbl_mgmt_genl_init(void) { return genl_register_family(&netlbl_mgmt_gnl_family); }
linux-master
net/netlabel/netlabel_mgmt.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Ethernet-type device handling. * * Version: @(#)eth.c 1.0.7 05/25/93 * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * Mark Evans, <[email protected]> * Florian La Roche, <[email protected]> * Alan Cox, <[email protected]> * * Fixes: * Mr Linux : Arp problems * Alan Cox : Generic queue tidyup (very tiny here) * Alan Cox : eth_header ntohs should be htons * Alan Cox : eth_rebuild_header missing an htons and * minor other things. * Tegge : Arp bug fixes. * Florian : Removed many unnecessary functions, code cleanup * and changes for new arp and skbuff. * Alan Cox : Redid header building to reflect new format. * Alan Cox : ARP only when compiled with CONFIG_INET * Greg Page : 802.2 and SNAP stuff. * Alan Cox : MAC layer pointers/new format. * Paul Gortmaker : eth_copy_and_sum shouldn't csum padding. * Alan Cox : Protect against forwarding explosions with * older network drivers and IFF_ALLMULTI. * Christer Weinigel : Better rebuild header message. * Andrew Morton : 26Feb01: kill ether_setup() - use netdev_boot_setup(). */ #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/inet.h> #include <linux/ip.h> #include <linux/netdevice.h> #include <linux/nvmem-consumer.h> #include <linux/etherdevice.h> #include <linux/skbuff.h> #include <linux/errno.h> #include <linux/init.h> #include <linux/if_ether.h> #include <linux/of_net.h> #include <linux/pci.h> #include <linux/property.h> #include <net/dst.h> #include <net/arp.h> #include <net/sock.h> #include <net/ipv6.h> #include <net/ip.h> #include <net/dsa.h> #include <net/flow_dissector.h> #include <net/gro.h> #include <linux/uaccess.h> #include <net/pkt_sched.h> /** * eth_header - create the Ethernet header * @skb: buffer to alter * @dev: source device * @type: Ethernet type field * @daddr: destination address (NULL leave destination address) * @saddr: source address (NULL use device source address) * @len: packet length (<= skb->len) * * * Set the protocol type. For a packet of type ETH_P_802_3/2 we put the length * in here instead. */ int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) { struct ethhdr *eth = skb_push(skb, ETH_HLEN); if (type != ETH_P_802_3 && type != ETH_P_802_2) eth->h_proto = htons(type); else eth->h_proto = htons(len); /* * Set the source hardware address. */ if (!saddr) saddr = dev->dev_addr; memcpy(eth->h_source, saddr, ETH_ALEN); if (daddr) { memcpy(eth->h_dest, daddr, ETH_ALEN); return ETH_HLEN; } /* * Anyway, the loopback-device should never use this function... */ if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) { eth_zero_addr(eth->h_dest); return ETH_HLEN; } return -ETH_HLEN; } EXPORT_SYMBOL(eth_header); /** * eth_get_headlen - determine the length of header for an ethernet frame * @dev: pointer to network device * @data: pointer to start of frame * @len: total length of frame * * Make a best effort attempt to pull the length for all of the headers for * a given frame in a linear buffer. */ u32 eth_get_headlen(const struct net_device *dev, const void *data, u32 len) { const unsigned int flags = FLOW_DISSECTOR_F_PARSE_1ST_FRAG; const struct ethhdr *eth = (const struct ethhdr *)data; struct flow_keys_basic keys; /* this should never happen, but better safe than sorry */ if (unlikely(len < sizeof(*eth))) return len; /* parse any remaining L2/L3 headers, check for L4 */ if (!skb_flow_dissect_flow_keys_basic(dev_net(dev), NULL, &keys, data, eth->h_proto, sizeof(*eth), len, flags)) return max_t(u32, keys.control.thoff, sizeof(*eth)); /* parse for any L4 headers */ return min_t(u32, __skb_get_poff(NULL, data, &keys, len), len); } EXPORT_SYMBOL(eth_get_headlen); /** * eth_type_trans - determine the packet's protocol ID. * @skb: received socket data * @dev: receiving network device * * The rule here is that we * assume 802.3 if the type field is short enough to be a length. * This is normal practice and works for any 'now in use' protocol. */ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) { unsigned short _service_access_point; const unsigned short *sap; const struct ethhdr *eth; skb->dev = dev; skb_reset_mac_header(skb); eth = (struct ethhdr *)skb->data; skb_pull_inline(skb, ETH_HLEN); if (unlikely(!ether_addr_equal_64bits(eth->h_dest, dev->dev_addr))) { if (unlikely(is_multicast_ether_addr_64bits(eth->h_dest))) { if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast)) skb->pkt_type = PACKET_BROADCAST; else skb->pkt_type = PACKET_MULTICAST; } else { skb->pkt_type = PACKET_OTHERHOST; } } /* * Some variants of DSA tagging don't have an ethertype field * at all, so we check here whether one of those tagging * variants has been configured on the receiving interface, * and if so, set skb->protocol without looking at the packet. */ if (unlikely(netdev_uses_dsa(dev))) return htons(ETH_P_XDSA); if (likely(eth_proto_is_802_3(eth->h_proto))) return eth->h_proto; /* * This is a magic hack to spot IPX packets. Older Novell breaks * the protocol design and runs IPX over 802.3 without an 802.2 LLC * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This * won't work for fault tolerant netware but does for the rest. */ sap = skb_header_pointer(skb, 0, sizeof(*sap), &_service_access_point); if (sap && *sap == 0xFFFF) return htons(ETH_P_802_3); /* * Real 802.2 LLC */ return htons(ETH_P_802_2); } EXPORT_SYMBOL(eth_type_trans); /** * eth_header_parse - extract hardware address from packet * @skb: packet to extract header from * @haddr: destination buffer */ int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr) { const struct ethhdr *eth = eth_hdr(skb); memcpy(haddr, eth->h_source, ETH_ALEN); return ETH_ALEN; } EXPORT_SYMBOL(eth_header_parse); /** * eth_header_cache - fill cache entry from neighbour * @neigh: source neighbour * @hh: destination cache entry * @type: Ethernet type field * * Create an Ethernet header template from the neighbour. */ int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type) { struct ethhdr *eth; const struct net_device *dev = neigh->dev; eth = (struct ethhdr *) (((u8 *) hh->hh_data) + (HH_DATA_OFF(sizeof(*eth)))); if (type == htons(ETH_P_802_3)) return -1; eth->h_proto = type; memcpy(eth->h_source, dev->dev_addr, ETH_ALEN); memcpy(eth->h_dest, neigh->ha, ETH_ALEN); /* Pairs with READ_ONCE() in neigh_resolve_output(), * neigh_hh_output() and neigh_update_hhs(). */ smp_store_release(&hh->hh_len, ETH_HLEN); return 0; } EXPORT_SYMBOL(eth_header_cache); /** * eth_header_cache_update - update cache entry * @hh: destination cache entry * @dev: network device * @haddr: new hardware address * * Called by Address Resolution module to notify changes in address. */ void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev, const unsigned char *haddr) { memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)), haddr, ETH_ALEN); } EXPORT_SYMBOL(eth_header_cache_update); /** * eth_header_parse_protocol - extract protocol from L2 header * @skb: packet to extract protocol from */ __be16 eth_header_parse_protocol(const struct sk_buff *skb) { const struct ethhdr *eth = eth_hdr(skb); return eth->h_proto; } EXPORT_SYMBOL(eth_header_parse_protocol); /** * eth_prepare_mac_addr_change - prepare for mac change * @dev: network device * @p: socket address */ int eth_prepare_mac_addr_change(struct net_device *dev, void *p) { struct sockaddr *addr = p; if (!(dev->priv_flags & IFF_LIVE_ADDR_CHANGE) && netif_running(dev)) return -EBUSY; if (!is_valid_ether_addr(addr->sa_data)) return -EADDRNOTAVAIL; return 0; } EXPORT_SYMBOL(eth_prepare_mac_addr_change); /** * eth_commit_mac_addr_change - commit mac change * @dev: network device * @p: socket address */ void eth_commit_mac_addr_change(struct net_device *dev, void *p) { struct sockaddr *addr = p; eth_hw_addr_set(dev, addr->sa_data); } EXPORT_SYMBOL(eth_commit_mac_addr_change); /** * eth_mac_addr - set new Ethernet hardware address * @dev: network device * @p: socket address * * Change hardware address of device. * * This doesn't change hardware matching, so needs to be overridden * for most real devices. */ int eth_mac_addr(struct net_device *dev, void *p) { int ret; ret = eth_prepare_mac_addr_change(dev, p); if (ret < 0) return ret; eth_commit_mac_addr_change(dev, p); return 0; } EXPORT_SYMBOL(eth_mac_addr); int eth_validate_addr(struct net_device *dev) { if (!is_valid_ether_addr(dev->dev_addr)) return -EADDRNOTAVAIL; return 0; } EXPORT_SYMBOL(eth_validate_addr); const struct header_ops eth_header_ops ____cacheline_aligned = { .create = eth_header, .parse = eth_header_parse, .cache = eth_header_cache, .cache_update = eth_header_cache_update, .parse_protocol = eth_header_parse_protocol, }; /** * ether_setup - setup Ethernet network device * @dev: network device * * Fill in the fields of the device structure with Ethernet-generic values. */ void ether_setup(struct net_device *dev) { dev->header_ops = &eth_header_ops; dev->type = ARPHRD_ETHER; dev->hard_header_len = ETH_HLEN; dev->min_header_len = ETH_HLEN; dev->mtu = ETH_DATA_LEN; dev->min_mtu = ETH_MIN_MTU; dev->max_mtu = ETH_DATA_LEN; dev->addr_len = ETH_ALEN; dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; dev->flags = IFF_BROADCAST|IFF_MULTICAST; dev->priv_flags |= IFF_TX_SKB_SHARING; eth_broadcast_addr(dev->broadcast); } EXPORT_SYMBOL(ether_setup); /** * alloc_etherdev_mqs - Allocates and sets up an Ethernet device * @sizeof_priv: Size of additional driver-private structure to be allocated * for this Ethernet device * @txqs: The number of TX queues this device has. * @rxqs: The number of RX queues this device has. * * Fill in the fields of the device structure with Ethernet-generic * values. Basically does everything except registering the device. * * Constructs a new net device, complete with a private data area of * size (sizeof_priv). A 32-byte (not bit) alignment is enforced for * this private data area. */ struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs, unsigned int rxqs) { return alloc_netdev_mqs(sizeof_priv, "eth%d", NET_NAME_ENUM, ether_setup, txqs, rxqs); } EXPORT_SYMBOL(alloc_etherdev_mqs); ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len) { return sysfs_emit(buf, "%*phC\n", len, addr); } EXPORT_SYMBOL(sysfs_format_mac); struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb) { const struct packet_offload *ptype; unsigned int hlen, off_eth; struct sk_buff *pp = NULL; struct ethhdr *eh, *eh2; struct sk_buff *p; __be16 type; int flush = 1; off_eth = skb_gro_offset(skb); hlen = off_eth + sizeof(*eh); eh = skb_gro_header(skb, hlen, off_eth); if (unlikely(!eh)) goto out; flush = 0; list_for_each_entry(p, head, list) { if (!NAPI_GRO_CB(p)->same_flow) continue; eh2 = (struct ethhdr *)(p->data + off_eth); if (compare_ether_header(eh, eh2)) { NAPI_GRO_CB(p)->same_flow = 0; continue; } } type = eh->h_proto; ptype = gro_find_receive_by_type(type); if (ptype == NULL) { flush = 1; goto out; } skb_gro_pull(skb, sizeof(*eh)); skb_gro_postpull_rcsum(skb, eh, sizeof(*eh)); pp = indirect_call_gro_receive_inet(ptype->callbacks.gro_receive, ipv6_gro_receive, inet_gro_receive, head, skb); out: skb_gro_flush_final(skb, pp, flush); return pp; } EXPORT_SYMBOL(eth_gro_receive); int eth_gro_complete(struct sk_buff *skb, int nhoff) { struct ethhdr *eh = (struct ethhdr *)(skb->data + nhoff); __be16 type = eh->h_proto; struct packet_offload *ptype; int err = -ENOSYS; if (skb->encapsulation) skb_set_inner_mac_header(skb, nhoff); ptype = gro_find_complete_by_type(type); if (ptype != NULL) err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete, ipv6_gro_complete, inet_gro_complete, skb, nhoff + sizeof(*eh)); return err; } EXPORT_SYMBOL(eth_gro_complete); static struct packet_offload eth_packet_offload __read_mostly = { .type = cpu_to_be16(ETH_P_TEB), .priority = 10, .callbacks = { .gro_receive = eth_gro_receive, .gro_complete = eth_gro_complete, }, }; static int __init eth_offload_init(void) { dev_add_offload(&eth_packet_offload); return 0; } fs_initcall(eth_offload_init); unsigned char * __weak arch_get_platform_mac_address(void) { return NULL; } int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr) { unsigned char *addr; int ret; ret = of_get_mac_address(dev->of_node, mac_addr); if (!ret) return 0; addr = arch_get_platform_mac_address(); if (!addr) return -ENODEV; ether_addr_copy(mac_addr, addr); return 0; } EXPORT_SYMBOL(eth_platform_get_mac_address); /** * platform_get_ethdev_address - Set netdev's MAC address from a given device * @dev: Pointer to the device * @netdev: Pointer to netdev to write the address to * * Wrapper around eth_platform_get_mac_address() which writes the address * directly to netdev->dev_addr. */ int platform_get_ethdev_address(struct device *dev, struct net_device *netdev) { u8 addr[ETH_ALEN] __aligned(2); int ret; ret = eth_platform_get_mac_address(dev, addr); if (!ret) eth_hw_addr_set(netdev, addr); return ret; } EXPORT_SYMBOL(platform_get_ethdev_address); /** * nvmem_get_mac_address - Obtain the MAC address from an nvmem cell named * 'mac-address' associated with given device. * * @dev: Device with which the mac-address cell is associated. * @addrbuf: Buffer to which the MAC address will be copied on success. * * Returns 0 on success or a negative error number on failure. */ int nvmem_get_mac_address(struct device *dev, void *addrbuf) { struct nvmem_cell *cell; const void *mac; size_t len; cell = nvmem_cell_get(dev, "mac-address"); if (IS_ERR(cell)) return PTR_ERR(cell); mac = nvmem_cell_read(cell, &len); nvmem_cell_put(cell); if (IS_ERR(mac)) return PTR_ERR(mac); if (len != ETH_ALEN || !is_valid_ether_addr(mac)) { kfree(mac); return -EINVAL; } ether_addr_copy(addrbuf, mac); kfree(mac); return 0; } static int fwnode_get_mac_addr(struct fwnode_handle *fwnode, const char *name, char *addr) { int ret; ret = fwnode_property_read_u8_array(fwnode, name, addr, ETH_ALEN); if (ret) return ret; if (!is_valid_ether_addr(addr)) return -EINVAL; return 0; } /** * fwnode_get_mac_address - Get the MAC from the firmware node * @fwnode: Pointer to the firmware node * @addr: Address of buffer to store the MAC in * * Search the firmware node for the best MAC address to use. 'mac-address' is * checked first, because that is supposed to contain to "most recent" MAC * address. If that isn't set, then 'local-mac-address' is checked next, * because that is the default address. If that isn't set, then the obsolete * 'address' is checked, just in case we're using an old device tree. * * Note that the 'address' property is supposed to contain a virtual address of * the register set, but some DTS files have redefined that property to be the * MAC address. * * All-zero MAC addresses are rejected, because those could be properties that * exist in the firmware tables, but were not updated by the firmware. For * example, the DTS could define 'mac-address' and 'local-mac-address', with * zero MAC addresses. Some older U-Boots only initialized 'local-mac-address'. * In this case, the real MAC is in 'local-mac-address', and 'mac-address' * exists but is all zeros. */ int fwnode_get_mac_address(struct fwnode_handle *fwnode, char *addr) { if (!fwnode_get_mac_addr(fwnode, "mac-address", addr) || !fwnode_get_mac_addr(fwnode, "local-mac-address", addr) || !fwnode_get_mac_addr(fwnode, "address", addr)) return 0; return -ENOENT; } EXPORT_SYMBOL(fwnode_get_mac_address); /** * device_get_mac_address - Get the MAC for a given device * @dev: Pointer to the device * @addr: Address of buffer to store the MAC in */ int device_get_mac_address(struct device *dev, char *addr) { return fwnode_get_mac_address(dev_fwnode(dev), addr); } EXPORT_SYMBOL(device_get_mac_address); /** * device_get_ethdev_address - Set netdev's MAC address from a given device * @dev: Pointer to the device * @netdev: Pointer to netdev to write the address to * * Wrapper around device_get_mac_address() which writes the address * directly to netdev->dev_addr. */ int device_get_ethdev_address(struct device *dev, struct net_device *netdev) { u8 addr[ETH_ALEN]; int ret; ret = device_get_mac_address(dev, addr); if (!ret) eth_hw_addr_set(netdev, addr); return ret; } EXPORT_SYMBOL(device_get_ethdev_address);
linux-master
net/ethernet/eth.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * net/l3mdev/l3mdev.c - L3 master device implementation * Copyright (c) 2015 Cumulus Networks * Copyright (c) 2015 David Ahern <[email protected]> */ #include <linux/netdevice.h> #include <net/fib_rules.h> #include <net/l3mdev.h> static DEFINE_SPINLOCK(l3mdev_lock); struct l3mdev_handler { lookup_by_table_id_t dev_lookup; }; static struct l3mdev_handler l3mdev_handlers[L3MDEV_TYPE_MAX + 1]; static int l3mdev_check_type(enum l3mdev_type l3type) { if (l3type <= L3MDEV_TYPE_UNSPEC || l3type > L3MDEV_TYPE_MAX) return -EINVAL; return 0; } int l3mdev_table_lookup_register(enum l3mdev_type l3type, lookup_by_table_id_t fn) { struct l3mdev_handler *hdlr; int res; res = l3mdev_check_type(l3type); if (res) return res; hdlr = &l3mdev_handlers[l3type]; spin_lock(&l3mdev_lock); if (hdlr->dev_lookup) { res = -EBUSY; goto unlock; } hdlr->dev_lookup = fn; res = 0; unlock: spin_unlock(&l3mdev_lock); return res; } EXPORT_SYMBOL_GPL(l3mdev_table_lookup_register); void l3mdev_table_lookup_unregister(enum l3mdev_type l3type, lookup_by_table_id_t fn) { struct l3mdev_handler *hdlr; if (l3mdev_check_type(l3type)) return; hdlr = &l3mdev_handlers[l3type]; spin_lock(&l3mdev_lock); if (hdlr->dev_lookup == fn) hdlr->dev_lookup = NULL; spin_unlock(&l3mdev_lock); } EXPORT_SYMBOL_GPL(l3mdev_table_lookup_unregister); int l3mdev_ifindex_lookup_by_table_id(enum l3mdev_type l3type, struct net *net, u32 table_id) { lookup_by_table_id_t lookup; struct l3mdev_handler *hdlr; int ifindex = -EINVAL; int res; res = l3mdev_check_type(l3type); if (res) return res; hdlr = &l3mdev_handlers[l3type]; spin_lock(&l3mdev_lock); lookup = hdlr->dev_lookup; if (!lookup) goto unlock; ifindex = lookup(net, table_id); unlock: spin_unlock(&l3mdev_lock); return ifindex; } EXPORT_SYMBOL_GPL(l3mdev_ifindex_lookup_by_table_id); /** * l3mdev_master_ifindex_rcu - get index of L3 master device * @dev: targeted interface */ int l3mdev_master_ifindex_rcu(const struct net_device *dev) { int ifindex = 0; if (!dev) return 0; if (netif_is_l3_master(dev)) { ifindex = dev->ifindex; } else if (netif_is_l3_slave(dev)) { struct net_device *master; struct net_device *_dev = (struct net_device *)dev; /* netdev_master_upper_dev_get_rcu calls * list_first_or_null_rcu to walk the upper dev list. * list_first_or_null_rcu does not handle a const arg. We aren't * making changes, just want the master device from that list so * typecast to remove the const */ master = netdev_master_upper_dev_get_rcu(_dev); if (master) ifindex = master->ifindex; } return ifindex; } EXPORT_SYMBOL_GPL(l3mdev_master_ifindex_rcu); /** * l3mdev_master_upper_ifindex_by_index_rcu - get index of upper l3 master * device * @net: network namespace for device index lookup * @ifindex: targeted interface */ int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex) { struct net_device *dev; dev = dev_get_by_index_rcu(net, ifindex); while (dev && !netif_is_l3_master(dev)) dev = netdev_master_upper_dev_get_rcu(dev); return dev ? dev->ifindex : 0; } EXPORT_SYMBOL_GPL(l3mdev_master_upper_ifindex_by_index_rcu); /** * l3mdev_fib_table_rcu - get FIB table id associated with an L3 * master interface * @dev: targeted interface */ u32 l3mdev_fib_table_rcu(const struct net_device *dev) { u32 tb_id = 0; if (!dev) return 0; if (netif_is_l3_master(dev)) { if (dev->l3mdev_ops->l3mdev_fib_table) tb_id = dev->l3mdev_ops->l3mdev_fib_table(dev); } else if (netif_is_l3_slave(dev)) { /* Users of netdev_master_upper_dev_get_rcu need non-const, * but current inet_*type functions take a const */ struct net_device *_dev = (struct net_device *) dev; const struct net_device *master; master = netdev_master_upper_dev_get_rcu(_dev); if (master && master->l3mdev_ops->l3mdev_fib_table) tb_id = master->l3mdev_ops->l3mdev_fib_table(master); } return tb_id; } EXPORT_SYMBOL_GPL(l3mdev_fib_table_rcu); u32 l3mdev_fib_table_by_index(struct net *net, int ifindex) { struct net_device *dev; u32 tb_id = 0; if (!ifindex) return 0; rcu_read_lock(); dev = dev_get_by_index_rcu(net, ifindex); if (dev) tb_id = l3mdev_fib_table_rcu(dev); rcu_read_unlock(); return tb_id; } EXPORT_SYMBOL_GPL(l3mdev_fib_table_by_index); /** * l3mdev_link_scope_lookup - IPv6 route lookup based on flow for link * local and multicast addresses * @net: network namespace for device index lookup * @fl6: IPv6 flow struct for lookup * This function does not hold refcnt on the returned dst. * Caller must hold rcu_read_lock(). */ struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6) { struct dst_entry *dst = NULL; struct net_device *dev; WARN_ON_ONCE(!rcu_read_lock_held()); if (fl6->flowi6_oif) { dev = dev_get_by_index_rcu(net, fl6->flowi6_oif); if (dev && netif_is_l3_slave(dev)) dev = netdev_master_upper_dev_get_rcu(dev); if (dev && netif_is_l3_master(dev) && dev->l3mdev_ops->l3mdev_link_scope_lookup) dst = dev->l3mdev_ops->l3mdev_link_scope_lookup(dev, fl6); } return dst; } EXPORT_SYMBOL_GPL(l3mdev_link_scope_lookup); /** * l3mdev_fib_rule_match - Determine if flowi references an * L3 master device * @net: network namespace for device index lookup * @fl: flow struct * @arg: store the table the rule matched with here */ int l3mdev_fib_rule_match(struct net *net, struct flowi *fl, struct fib_lookup_arg *arg) { struct net_device *dev; int rc = 0; /* update flow ensures flowi_l3mdev is set when relevant */ if (!fl->flowi_l3mdev) return 0; rcu_read_lock(); dev = dev_get_by_index_rcu(net, fl->flowi_l3mdev); if (dev && netif_is_l3_master(dev) && dev->l3mdev_ops->l3mdev_fib_table) { arg->table = dev->l3mdev_ops->l3mdev_fib_table(dev); rc = 1; } rcu_read_unlock(); return rc; } void l3mdev_update_flow(struct net *net, struct flowi *fl) { struct net_device *dev; rcu_read_lock(); if (fl->flowi_oif) { dev = dev_get_by_index_rcu(net, fl->flowi_oif); if (dev) { if (!fl->flowi_l3mdev) fl->flowi_l3mdev = l3mdev_master_ifindex_rcu(dev); /* oif set to L3mdev directs lookup to its table; * reset to avoid oif match in fib_lookup */ if (netif_is_l3_master(dev)) fl->flowi_oif = 0; goto out; } } if (fl->flowi_iif > LOOPBACK_IFINDEX && !fl->flowi_l3mdev) { dev = dev_get_by_index_rcu(net, fl->flowi_iif); if (dev) fl->flowi_l3mdev = l3mdev_master_ifindex_rcu(dev); } out: rcu_read_unlock(); } EXPORT_SYMBOL_GPL(l3mdev_update_flow);
linux-master
net/l3mdev/l3mdev.c
// SPDX-License-Identifier: GPL-2.0-only // Copyright (c) 2020 Facebook Inc. #include <linux/ethtool_netlink.h> #include <linux/netdevice.h> #include <linux/slab.h> #include <linux/types.h> #include <linux/workqueue.h> #include <net/udp_tunnel.h> #include <net/vxlan.h> enum udp_tunnel_nic_table_entry_flags { UDP_TUNNEL_NIC_ENTRY_ADD = BIT(0), UDP_TUNNEL_NIC_ENTRY_DEL = BIT(1), UDP_TUNNEL_NIC_ENTRY_OP_FAIL = BIT(2), UDP_TUNNEL_NIC_ENTRY_FROZEN = BIT(3), }; struct udp_tunnel_nic_table_entry { __be16 port; u8 type; u8 flags; u16 use_cnt; #define UDP_TUNNEL_NIC_USE_CNT_MAX U16_MAX u8 hw_priv; }; /** * struct udp_tunnel_nic - UDP tunnel port offload state * @work: async work for talking to hardware from process context * @dev: netdev pointer * @need_sync: at least one port start changed * @need_replay: space was freed, we need a replay of all ports * @work_pending: @work is currently scheduled * @n_tables: number of tables under @entries * @missed: bitmap of tables which overflown * @entries: table of tables of ports currently offloaded */ struct udp_tunnel_nic { struct work_struct work; struct net_device *dev; u8 need_sync:1; u8 need_replay:1; u8 work_pending:1; unsigned int n_tables; unsigned long missed; struct udp_tunnel_nic_table_entry **entries; }; /* We ensure all work structs are done using driver state, but not the code. * We need a workqueue we can flush before module gets removed. */ static struct workqueue_struct *udp_tunnel_nic_workqueue; static const char *udp_tunnel_nic_tunnel_type_name(unsigned int type) { switch (type) { case UDP_TUNNEL_TYPE_VXLAN: return "vxlan"; case UDP_TUNNEL_TYPE_GENEVE: return "geneve"; case UDP_TUNNEL_TYPE_VXLAN_GPE: return "vxlan-gpe"; default: return "unknown"; } } static bool udp_tunnel_nic_entry_is_free(struct udp_tunnel_nic_table_entry *entry) { return entry->use_cnt == 0 && !entry->flags; } static bool udp_tunnel_nic_entry_is_present(struct udp_tunnel_nic_table_entry *entry) { return entry->use_cnt && !(entry->flags & ~UDP_TUNNEL_NIC_ENTRY_FROZEN); } static bool udp_tunnel_nic_entry_is_frozen(struct udp_tunnel_nic_table_entry *entry) { return entry->flags & UDP_TUNNEL_NIC_ENTRY_FROZEN; } static void udp_tunnel_nic_entry_freeze_used(struct udp_tunnel_nic_table_entry *entry) { if (!udp_tunnel_nic_entry_is_free(entry)) entry->flags |= UDP_TUNNEL_NIC_ENTRY_FROZEN; } static void udp_tunnel_nic_entry_unfreeze(struct udp_tunnel_nic_table_entry *entry) { entry->flags &= ~UDP_TUNNEL_NIC_ENTRY_FROZEN; } static bool udp_tunnel_nic_entry_is_queued(struct udp_tunnel_nic_table_entry *entry) { return entry->flags & (UDP_TUNNEL_NIC_ENTRY_ADD | UDP_TUNNEL_NIC_ENTRY_DEL); } static void udp_tunnel_nic_entry_queue(struct udp_tunnel_nic *utn, struct udp_tunnel_nic_table_entry *entry, unsigned int flag) { entry->flags |= flag; utn->need_sync = 1; } static void udp_tunnel_nic_ti_from_entry(struct udp_tunnel_nic_table_entry *entry, struct udp_tunnel_info *ti) { memset(ti, 0, sizeof(*ti)); ti->port = entry->port; ti->type = entry->type; ti->hw_priv = entry->hw_priv; } static bool udp_tunnel_nic_is_empty(struct net_device *dev, struct udp_tunnel_nic *utn) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; unsigned int i, j; for (i = 0; i < utn->n_tables; i++) for (j = 0; j < info->tables[i].n_entries; j++) if (!udp_tunnel_nic_entry_is_free(&utn->entries[i][j])) return false; return true; } static bool udp_tunnel_nic_should_replay(struct net_device *dev, struct udp_tunnel_nic *utn) { const struct udp_tunnel_nic_table_info *table; unsigned int i, j; if (!utn->missed) return false; for (i = 0; i < utn->n_tables; i++) { table = &dev->udp_tunnel_nic_info->tables[i]; if (!test_bit(i, &utn->missed)) continue; for (j = 0; j < table->n_entries; j++) if (udp_tunnel_nic_entry_is_free(&utn->entries[i][j])) return true; } return false; } static void __udp_tunnel_nic_get_port(struct net_device *dev, unsigned int table, unsigned int idx, struct udp_tunnel_info *ti) { struct udp_tunnel_nic_table_entry *entry; struct udp_tunnel_nic *utn; utn = dev->udp_tunnel_nic; entry = &utn->entries[table][idx]; if (entry->use_cnt) udp_tunnel_nic_ti_from_entry(entry, ti); } static void __udp_tunnel_nic_set_port_priv(struct net_device *dev, unsigned int table, unsigned int idx, u8 priv) { dev->udp_tunnel_nic->entries[table][idx].hw_priv = priv; } static void udp_tunnel_nic_entry_update_done(struct udp_tunnel_nic_table_entry *entry, int err) { bool dodgy = entry->flags & UDP_TUNNEL_NIC_ENTRY_OP_FAIL; WARN_ON_ONCE(entry->flags & UDP_TUNNEL_NIC_ENTRY_ADD && entry->flags & UDP_TUNNEL_NIC_ENTRY_DEL); if (entry->flags & UDP_TUNNEL_NIC_ENTRY_ADD && (!err || (err == -EEXIST && dodgy))) entry->flags &= ~UDP_TUNNEL_NIC_ENTRY_ADD; if (entry->flags & UDP_TUNNEL_NIC_ENTRY_DEL && (!err || (err == -ENOENT && dodgy))) entry->flags &= ~UDP_TUNNEL_NIC_ENTRY_DEL; if (!err) entry->flags &= ~UDP_TUNNEL_NIC_ENTRY_OP_FAIL; else entry->flags |= UDP_TUNNEL_NIC_ENTRY_OP_FAIL; } static void udp_tunnel_nic_device_sync_one(struct net_device *dev, struct udp_tunnel_nic *utn, unsigned int table, unsigned int idx) { struct udp_tunnel_nic_table_entry *entry; struct udp_tunnel_info ti; int err; entry = &utn->entries[table][idx]; if (!udp_tunnel_nic_entry_is_queued(entry)) return; udp_tunnel_nic_ti_from_entry(entry, &ti); if (entry->flags & UDP_TUNNEL_NIC_ENTRY_ADD) err = dev->udp_tunnel_nic_info->set_port(dev, table, idx, &ti); else err = dev->udp_tunnel_nic_info->unset_port(dev, table, idx, &ti); udp_tunnel_nic_entry_update_done(entry, err); if (err) netdev_warn(dev, "UDP tunnel port sync failed port %d type %s: %d\n", be16_to_cpu(entry->port), udp_tunnel_nic_tunnel_type_name(entry->type), err); } static void udp_tunnel_nic_device_sync_by_port(struct net_device *dev, struct udp_tunnel_nic *utn) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; unsigned int i, j; for (i = 0; i < utn->n_tables; i++) for (j = 0; j < info->tables[i].n_entries; j++) udp_tunnel_nic_device_sync_one(dev, utn, i, j); } static void udp_tunnel_nic_device_sync_by_table(struct net_device *dev, struct udp_tunnel_nic *utn) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; unsigned int i, j; int err; for (i = 0; i < utn->n_tables; i++) { /* Find something that needs sync in this table */ for (j = 0; j < info->tables[i].n_entries; j++) if (udp_tunnel_nic_entry_is_queued(&utn->entries[i][j])) break; if (j == info->tables[i].n_entries) continue; err = info->sync_table(dev, i); if (err) netdev_warn(dev, "UDP tunnel port sync failed for table %d: %d\n", i, err); for (j = 0; j < info->tables[i].n_entries; j++) { struct udp_tunnel_nic_table_entry *entry; entry = &utn->entries[i][j]; if (udp_tunnel_nic_entry_is_queued(entry)) udp_tunnel_nic_entry_update_done(entry, err); } } } static void __udp_tunnel_nic_device_sync(struct net_device *dev, struct udp_tunnel_nic *utn) { if (!utn->need_sync) return; if (dev->udp_tunnel_nic_info->sync_table) udp_tunnel_nic_device_sync_by_table(dev, utn); else udp_tunnel_nic_device_sync_by_port(dev, utn); utn->need_sync = 0; /* Can't replay directly here, in case we come from the tunnel driver's * notification - trying to replay may deadlock inside tunnel driver. */ utn->need_replay = udp_tunnel_nic_should_replay(dev, utn); } static void udp_tunnel_nic_device_sync(struct net_device *dev, struct udp_tunnel_nic *utn) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; bool may_sleep; if (!utn->need_sync) return; /* Drivers which sleep in the callback need to update from * the workqueue, if we come from the tunnel driver's notification. */ may_sleep = info->flags & UDP_TUNNEL_NIC_INFO_MAY_SLEEP; if (!may_sleep) __udp_tunnel_nic_device_sync(dev, utn); if (may_sleep || utn->need_replay) { queue_work(udp_tunnel_nic_workqueue, &utn->work); utn->work_pending = 1; } } static bool udp_tunnel_nic_table_is_capable(const struct udp_tunnel_nic_table_info *table, struct udp_tunnel_info *ti) { return table->tunnel_types & ti->type; } static bool udp_tunnel_nic_is_capable(struct net_device *dev, struct udp_tunnel_nic *utn, struct udp_tunnel_info *ti) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; unsigned int i; /* Special case IPv4-only NICs */ if (info->flags & UDP_TUNNEL_NIC_INFO_IPV4_ONLY && ti->sa_family != AF_INET) return false; for (i = 0; i < utn->n_tables; i++) if (udp_tunnel_nic_table_is_capable(&info->tables[i], ti)) return true; return false; } static int udp_tunnel_nic_has_collision(struct net_device *dev, struct udp_tunnel_nic *utn, struct udp_tunnel_info *ti) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; struct udp_tunnel_nic_table_entry *entry; unsigned int i, j; for (i = 0; i < utn->n_tables; i++) for (j = 0; j < info->tables[i].n_entries; j++) { entry = &utn->entries[i][j]; if (!udp_tunnel_nic_entry_is_free(entry) && entry->port == ti->port && entry->type != ti->type) { __set_bit(i, &utn->missed); return true; } } return false; } static void udp_tunnel_nic_entry_adj(struct udp_tunnel_nic *utn, unsigned int table, unsigned int idx, int use_cnt_adj) { struct udp_tunnel_nic_table_entry *entry = &utn->entries[table][idx]; bool dodgy = entry->flags & UDP_TUNNEL_NIC_ENTRY_OP_FAIL; unsigned int from, to; WARN_ON(entry->use_cnt + (u32)use_cnt_adj > U16_MAX); /* If not going from used to unused or vice versa - all done. * For dodgy entries make sure we try to sync again (queue the entry). */ entry->use_cnt += use_cnt_adj; if (!dodgy && !entry->use_cnt == !(entry->use_cnt - use_cnt_adj)) return; /* Cancel the op before it was sent to the device, if possible, * otherwise we'd need to take special care to issue commands * in the same order the ports arrived. */ if (use_cnt_adj < 0) { from = UDP_TUNNEL_NIC_ENTRY_ADD; to = UDP_TUNNEL_NIC_ENTRY_DEL; } else { from = UDP_TUNNEL_NIC_ENTRY_DEL; to = UDP_TUNNEL_NIC_ENTRY_ADD; } if (entry->flags & from) { entry->flags &= ~from; if (!dodgy) return; } udp_tunnel_nic_entry_queue(utn, entry, to); } static bool udp_tunnel_nic_entry_try_adj(struct udp_tunnel_nic *utn, unsigned int table, unsigned int idx, struct udp_tunnel_info *ti, int use_cnt_adj) { struct udp_tunnel_nic_table_entry *entry = &utn->entries[table][idx]; if (udp_tunnel_nic_entry_is_free(entry) || entry->port != ti->port || entry->type != ti->type) return false; if (udp_tunnel_nic_entry_is_frozen(entry)) return true; udp_tunnel_nic_entry_adj(utn, table, idx, use_cnt_adj); return true; } /* Try to find existing matching entry and adjust its use count, instead of * adding a new one. Returns true if entry was found. In case of delete the * entry may have gotten removed in the process, in which case it will be * queued for removal. */ static bool udp_tunnel_nic_try_existing(struct net_device *dev, struct udp_tunnel_nic *utn, struct udp_tunnel_info *ti, int use_cnt_adj) { const struct udp_tunnel_nic_table_info *table; unsigned int i, j; for (i = 0; i < utn->n_tables; i++) { table = &dev->udp_tunnel_nic_info->tables[i]; if (!udp_tunnel_nic_table_is_capable(table, ti)) continue; for (j = 0; j < table->n_entries; j++) if (udp_tunnel_nic_entry_try_adj(utn, i, j, ti, use_cnt_adj)) return true; } return false; } static bool udp_tunnel_nic_add_existing(struct net_device *dev, struct udp_tunnel_nic *utn, struct udp_tunnel_info *ti) { return udp_tunnel_nic_try_existing(dev, utn, ti, +1); } static bool udp_tunnel_nic_del_existing(struct net_device *dev, struct udp_tunnel_nic *utn, struct udp_tunnel_info *ti) { return udp_tunnel_nic_try_existing(dev, utn, ti, -1); } static bool udp_tunnel_nic_add_new(struct net_device *dev, struct udp_tunnel_nic *utn, struct udp_tunnel_info *ti) { const struct udp_tunnel_nic_table_info *table; unsigned int i, j; for (i = 0; i < utn->n_tables; i++) { table = &dev->udp_tunnel_nic_info->tables[i]; if (!udp_tunnel_nic_table_is_capable(table, ti)) continue; for (j = 0; j < table->n_entries; j++) { struct udp_tunnel_nic_table_entry *entry; entry = &utn->entries[i][j]; if (!udp_tunnel_nic_entry_is_free(entry)) continue; entry->port = ti->port; entry->type = ti->type; entry->use_cnt = 1; udp_tunnel_nic_entry_queue(utn, entry, UDP_TUNNEL_NIC_ENTRY_ADD); return true; } /* The different table may still fit this port in, but there * are no devices currently which have multiple tables accepting * the same tunnel type, and false positives are okay. */ __set_bit(i, &utn->missed); } return false; } static void __udp_tunnel_nic_add_port(struct net_device *dev, struct udp_tunnel_info *ti) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; struct udp_tunnel_nic *utn; utn = dev->udp_tunnel_nic; if (!utn) return; if (!netif_running(dev) && info->flags & UDP_TUNNEL_NIC_INFO_OPEN_ONLY) return; if (info->flags & UDP_TUNNEL_NIC_INFO_STATIC_IANA_VXLAN && ti->port == htons(IANA_VXLAN_UDP_PORT)) { if (ti->type != UDP_TUNNEL_TYPE_VXLAN) netdev_warn(dev, "device assumes port 4789 will be used by vxlan tunnels\n"); return; } if (!udp_tunnel_nic_is_capable(dev, utn, ti)) return; /* It may happen that a tunnel of one type is removed and different * tunnel type tries to reuse its port before the device was informed. * Rely on utn->missed to re-add this port later. */ if (udp_tunnel_nic_has_collision(dev, utn, ti)) return; if (!udp_tunnel_nic_add_existing(dev, utn, ti)) udp_tunnel_nic_add_new(dev, utn, ti); udp_tunnel_nic_device_sync(dev, utn); } static void __udp_tunnel_nic_del_port(struct net_device *dev, struct udp_tunnel_info *ti) { struct udp_tunnel_nic *utn; utn = dev->udp_tunnel_nic; if (!utn) return; if (!udp_tunnel_nic_is_capable(dev, utn, ti)) return; udp_tunnel_nic_del_existing(dev, utn, ti); udp_tunnel_nic_device_sync(dev, utn); } static void __udp_tunnel_nic_reset_ntf(struct net_device *dev) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; struct udp_tunnel_nic *utn; unsigned int i, j; ASSERT_RTNL(); utn = dev->udp_tunnel_nic; if (!utn) return; utn->need_sync = false; for (i = 0; i < utn->n_tables; i++) for (j = 0; j < info->tables[i].n_entries; j++) { struct udp_tunnel_nic_table_entry *entry; entry = &utn->entries[i][j]; entry->flags &= ~(UDP_TUNNEL_NIC_ENTRY_DEL | UDP_TUNNEL_NIC_ENTRY_OP_FAIL); /* We don't release rtnl across ops */ WARN_ON(entry->flags & UDP_TUNNEL_NIC_ENTRY_FROZEN); if (!entry->use_cnt) continue; udp_tunnel_nic_entry_queue(utn, entry, UDP_TUNNEL_NIC_ENTRY_ADD); } __udp_tunnel_nic_device_sync(dev, utn); } static size_t __udp_tunnel_nic_dump_size(struct net_device *dev, unsigned int table) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; struct udp_tunnel_nic *utn; unsigned int j; size_t size; utn = dev->udp_tunnel_nic; if (!utn) return 0; size = 0; for (j = 0; j < info->tables[table].n_entries; j++) { if (!udp_tunnel_nic_entry_is_present(&utn->entries[table][j])) continue; size += nla_total_size(0) + /* _TABLE_ENTRY */ nla_total_size(sizeof(__be16)) + /* _ENTRY_PORT */ nla_total_size(sizeof(u32)); /* _ENTRY_TYPE */ } return size; } static int __udp_tunnel_nic_dump_write(struct net_device *dev, unsigned int table, struct sk_buff *skb) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; struct udp_tunnel_nic *utn; struct nlattr *nest; unsigned int j; utn = dev->udp_tunnel_nic; if (!utn) return 0; for (j = 0; j < info->tables[table].n_entries; j++) { if (!udp_tunnel_nic_entry_is_present(&utn->entries[table][j])) continue; nest = nla_nest_start(skb, ETHTOOL_A_TUNNEL_UDP_TABLE_ENTRY); if (!nest) return -EMSGSIZE; if (nla_put_be16(skb, ETHTOOL_A_TUNNEL_UDP_ENTRY_PORT, utn->entries[table][j].port) || nla_put_u32(skb, ETHTOOL_A_TUNNEL_UDP_ENTRY_TYPE, ilog2(utn->entries[table][j].type))) goto err_cancel; nla_nest_end(skb, nest); } return 0; err_cancel: nla_nest_cancel(skb, nest); return -EMSGSIZE; } static const struct udp_tunnel_nic_ops __udp_tunnel_nic_ops = { .get_port = __udp_tunnel_nic_get_port, .set_port_priv = __udp_tunnel_nic_set_port_priv, .add_port = __udp_tunnel_nic_add_port, .del_port = __udp_tunnel_nic_del_port, .reset_ntf = __udp_tunnel_nic_reset_ntf, .dump_size = __udp_tunnel_nic_dump_size, .dump_write = __udp_tunnel_nic_dump_write, }; static void udp_tunnel_nic_flush(struct net_device *dev, struct udp_tunnel_nic *utn) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; unsigned int i, j; for (i = 0; i < utn->n_tables; i++) for (j = 0; j < info->tables[i].n_entries; j++) { int adj_cnt = -utn->entries[i][j].use_cnt; if (adj_cnt) udp_tunnel_nic_entry_adj(utn, i, j, adj_cnt); } __udp_tunnel_nic_device_sync(dev, utn); for (i = 0; i < utn->n_tables; i++) memset(utn->entries[i], 0, array_size(info->tables[i].n_entries, sizeof(**utn->entries))); WARN_ON(utn->need_sync); utn->need_replay = 0; } static void udp_tunnel_nic_replay(struct net_device *dev, struct udp_tunnel_nic *utn) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; struct udp_tunnel_nic_shared_node *node; unsigned int i, j; /* Freeze all the ports we are already tracking so that the replay * does not double up the refcount. */ for (i = 0; i < utn->n_tables; i++) for (j = 0; j < info->tables[i].n_entries; j++) udp_tunnel_nic_entry_freeze_used(&utn->entries[i][j]); utn->missed = 0; utn->need_replay = 0; if (!info->shared) { udp_tunnel_get_rx_info(dev); } else { list_for_each_entry(node, &info->shared->devices, list) udp_tunnel_get_rx_info(node->dev); } for (i = 0; i < utn->n_tables; i++) for (j = 0; j < info->tables[i].n_entries; j++) udp_tunnel_nic_entry_unfreeze(&utn->entries[i][j]); } static void udp_tunnel_nic_device_sync_work(struct work_struct *work) { struct udp_tunnel_nic *utn = container_of(work, struct udp_tunnel_nic, work); rtnl_lock(); utn->work_pending = 0; __udp_tunnel_nic_device_sync(utn->dev, utn); if (utn->need_replay) udp_tunnel_nic_replay(utn->dev, utn); rtnl_unlock(); } static struct udp_tunnel_nic * udp_tunnel_nic_alloc(const struct udp_tunnel_nic_info *info, unsigned int n_tables) { struct udp_tunnel_nic *utn; unsigned int i; utn = kzalloc(sizeof(*utn), GFP_KERNEL); if (!utn) return NULL; utn->n_tables = n_tables; INIT_WORK(&utn->work, udp_tunnel_nic_device_sync_work); utn->entries = kmalloc_array(n_tables, sizeof(void *), GFP_KERNEL); if (!utn->entries) goto err_free_utn; for (i = 0; i < n_tables; i++) { utn->entries[i] = kcalloc(info->tables[i].n_entries, sizeof(*utn->entries[i]), GFP_KERNEL); if (!utn->entries[i]) goto err_free_prev_entries; } return utn; err_free_prev_entries: while (i--) kfree(utn->entries[i]); kfree(utn->entries); err_free_utn: kfree(utn); return NULL; } static void udp_tunnel_nic_free(struct udp_tunnel_nic *utn) { unsigned int i; for (i = 0; i < utn->n_tables; i++) kfree(utn->entries[i]); kfree(utn->entries); kfree(utn); } static int udp_tunnel_nic_register(struct net_device *dev) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; struct udp_tunnel_nic_shared_node *node = NULL; struct udp_tunnel_nic *utn; unsigned int n_tables, i; BUILD_BUG_ON(sizeof(utn->missed) * BITS_PER_BYTE < UDP_TUNNEL_NIC_MAX_TABLES); /* Expect use count of at most 2 (IPv4, IPv6) per device */ BUILD_BUG_ON(UDP_TUNNEL_NIC_USE_CNT_MAX < UDP_TUNNEL_NIC_MAX_SHARING_DEVICES * 2); /* Check that the driver info is sane */ if (WARN_ON(!info->set_port != !info->unset_port) || WARN_ON(!info->set_port == !info->sync_table) || WARN_ON(!info->tables[0].n_entries)) return -EINVAL; if (WARN_ON(info->shared && info->flags & UDP_TUNNEL_NIC_INFO_OPEN_ONLY)) return -EINVAL; n_tables = 1; for (i = 1; i < UDP_TUNNEL_NIC_MAX_TABLES; i++) { if (!info->tables[i].n_entries) continue; n_tables++; if (WARN_ON(!info->tables[i - 1].n_entries)) return -EINVAL; } /* Create UDP tunnel state structures */ if (info->shared) { node = kzalloc(sizeof(*node), GFP_KERNEL); if (!node) return -ENOMEM; node->dev = dev; } if (info->shared && info->shared->udp_tunnel_nic_info) { utn = info->shared->udp_tunnel_nic_info; } else { utn = udp_tunnel_nic_alloc(info, n_tables); if (!utn) { kfree(node); return -ENOMEM; } } if (info->shared) { if (!info->shared->udp_tunnel_nic_info) { INIT_LIST_HEAD(&info->shared->devices); info->shared->udp_tunnel_nic_info = utn; } list_add_tail(&node->list, &info->shared->devices); } utn->dev = dev; dev_hold(dev); dev->udp_tunnel_nic = utn; if (!(info->flags & UDP_TUNNEL_NIC_INFO_OPEN_ONLY)) udp_tunnel_get_rx_info(dev); return 0; } static void udp_tunnel_nic_unregister(struct net_device *dev, struct udp_tunnel_nic *utn) { const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; /* For a shared table remove this dev from the list of sharing devices * and if there are other devices just detach. */ if (info->shared) { struct udp_tunnel_nic_shared_node *node, *first; list_for_each_entry(node, &info->shared->devices, list) if (node->dev == dev) break; if (list_entry_is_head(node, &info->shared->devices, list)) return; list_del(&node->list); kfree(node); first = list_first_entry_or_null(&info->shared->devices, typeof(*first), list); if (first) { udp_tunnel_drop_rx_info(dev); utn->dev = first->dev; goto release_dev; } info->shared->udp_tunnel_nic_info = NULL; } /* Flush before we check work, so we don't waste time adding entries * from the work which we will boot immediately. */ udp_tunnel_nic_flush(dev, utn); /* Wait for the work to be done using the state, netdev core will * retry unregister until we give up our reference on this device. */ if (utn->work_pending) return; udp_tunnel_nic_free(utn); release_dev: dev->udp_tunnel_nic = NULL; dev_put(dev); } static int udp_tunnel_nic_netdevice_event(struct notifier_block *unused, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); const struct udp_tunnel_nic_info *info; struct udp_tunnel_nic *utn; info = dev->udp_tunnel_nic_info; if (!info) return NOTIFY_DONE; if (event == NETDEV_REGISTER) { int err; err = udp_tunnel_nic_register(dev); if (err) netdev_WARN(dev, "failed to register for UDP tunnel offloads: %d", err); return notifier_from_errno(err); } /* All other events will need the udp_tunnel_nic state */ utn = dev->udp_tunnel_nic; if (!utn) return NOTIFY_DONE; if (event == NETDEV_UNREGISTER) { udp_tunnel_nic_unregister(dev, utn); return NOTIFY_OK; } /* All other events only matter if NIC has to be programmed open */ if (!(info->flags & UDP_TUNNEL_NIC_INFO_OPEN_ONLY)) return NOTIFY_DONE; if (event == NETDEV_UP) { WARN_ON(!udp_tunnel_nic_is_empty(dev, utn)); udp_tunnel_get_rx_info(dev); return NOTIFY_OK; } if (event == NETDEV_GOING_DOWN) { udp_tunnel_nic_flush(dev, utn); return NOTIFY_OK; } return NOTIFY_DONE; } static struct notifier_block udp_tunnel_nic_notifier_block __read_mostly = { .notifier_call = udp_tunnel_nic_netdevice_event, }; static int __init udp_tunnel_nic_init_module(void) { int err; udp_tunnel_nic_workqueue = alloc_ordered_workqueue("udp_tunnel_nic", 0); if (!udp_tunnel_nic_workqueue) return -ENOMEM; rtnl_lock(); udp_tunnel_nic_ops = &__udp_tunnel_nic_ops; rtnl_unlock(); err = register_netdevice_notifier(&udp_tunnel_nic_notifier_block); if (err) goto err_unset_ops; return 0; err_unset_ops: rtnl_lock(); udp_tunnel_nic_ops = NULL; rtnl_unlock(); destroy_workqueue(udp_tunnel_nic_workqueue); return err; } late_initcall(udp_tunnel_nic_init_module); static void __exit udp_tunnel_nic_cleanup_module(void) { unregister_netdevice_notifier(&udp_tunnel_nic_notifier_block); rtnl_lock(); udp_tunnel_nic_ops = NULL; rtnl_unlock(); destroy_workqueue(udp_tunnel_nic_workqueue); } module_exit(udp_tunnel_nic_cleanup_module); MODULE_LICENSE("GPL");
linux-master
net/ipv4/udp_tunnel_nic.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * IP multicast routing support for mrouted 3.6/3.8 * * (c) 1995 Alan Cox, <[email protected]> * Linux Consultancy and Custom Driver Development * * Fixes: * Michael Chastain : Incorrect size of copying. * Alan Cox : Added the cache manager code * Alan Cox : Fixed the clone/copy bug and device race. * Mike McLagan : Routing by source * Malcolm Beattie : Buffer handling fixes. * Alexey Kuznetsov : Double buffer free and other fixes. * SVR Anand : Fixed several multicast bugs and problems. * Alexey Kuznetsov : Status, optimisations and more. * Brad Parker : Better behaviour on mrouted upcall * overflow. * Carlos Picoto : PIMv1 Support * Pavlin Ivanov Radoslavov: PIMv2 Registers must checksum only PIM header * Relax this requirement to work with older peers. */ #include <linux/uaccess.h> #include <linux/types.h> #include <linux/cache.h> #include <linux/capability.h> #include <linux/errno.h> #include <linux/mm.h> #include <linux/kernel.h> #include <linux/fcntl.h> #include <linux/stat.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <linux/inetdevice.h> #include <linux/igmp.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/mroute.h> #include <linux/init.h> #include <linux/if_ether.h> #include <linux/slab.h> #include <net/net_namespace.h> #include <net/ip.h> #include <net/protocol.h> #include <linux/skbuff.h> #include <net/route.h> #include <net/icmp.h> #include <net/udp.h> #include <net/raw.h> #include <linux/notifier.h> #include <linux/if_arp.h> #include <linux/netfilter_ipv4.h> #include <linux/compat.h> #include <linux/export.h> #include <linux/rhashtable.h> #include <net/ip_tunnels.h> #include <net/checksum.h> #include <net/netlink.h> #include <net/fib_rules.h> #include <linux/netconf.h> #include <net/rtnh.h> #include <linux/nospec.h> struct ipmr_rule { struct fib_rule common; }; struct ipmr_result { struct mr_table *mrt; }; /* Big lock, protecting vif table, mrt cache and mroute socket state. * Note that the changes are semaphored via rtnl_lock. */ static DEFINE_SPINLOCK(mrt_lock); static struct net_device *vif_dev_read(const struct vif_device *vif) { return rcu_dereference(vif->dev); } /* Multicast router control variables */ /* Special spinlock for queue of unresolved entries */ static DEFINE_SPINLOCK(mfc_unres_lock); /* We return to original Alan's scheme. Hash table of resolved * entries is changed only in process context and protected * with weak lock mrt_lock. Queue of unresolved entries is protected * with strong spinlock mfc_unres_lock. * * In this case data path is free of exclusive locks at all. */ static struct kmem_cache *mrt_cachep __ro_after_init; static struct mr_table *ipmr_new_table(struct net *net, u32 id); static void ipmr_free_table(struct mr_table *mrt); static void ip_mr_forward(struct net *net, struct mr_table *mrt, struct net_device *dev, struct sk_buff *skb, struct mfc_cache *cache, int local); static int ipmr_cache_report(const struct mr_table *mrt, struct sk_buff *pkt, vifi_t vifi, int assert); static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc, int cmd); static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt); static void mroute_clean_tables(struct mr_table *mrt, int flags); static void ipmr_expire_process(struct timer_list *t); #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES #define ipmr_for_each_table(mrt, net) \ list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list, \ lockdep_rtnl_is_held() || \ list_empty(&net->ipv4.mr_tables)) static struct mr_table *ipmr_mr_table_iter(struct net *net, struct mr_table *mrt) { struct mr_table *ret; if (!mrt) ret = list_entry_rcu(net->ipv4.mr_tables.next, struct mr_table, list); else ret = list_entry_rcu(mrt->list.next, struct mr_table, list); if (&ret->list == &net->ipv4.mr_tables) return NULL; return ret; } static struct mr_table *ipmr_get_table(struct net *net, u32 id) { struct mr_table *mrt; ipmr_for_each_table(mrt, net) { if (mrt->id == id) return mrt; } return NULL; } static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4, struct mr_table **mrt) { int err; struct ipmr_result res; struct fib_lookup_arg arg = { .result = &res, .flags = FIB_LOOKUP_NOREF, }; /* update flow if oif or iif point to device enslaved to l3mdev */ l3mdev_update_flow(net, flowi4_to_flowi(flp4)); err = fib_rules_lookup(net->ipv4.mr_rules_ops, flowi4_to_flowi(flp4), 0, &arg); if (err < 0) return err; *mrt = res.mrt; return 0; } static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp, int flags, struct fib_lookup_arg *arg) { struct ipmr_result *res = arg->result; struct mr_table *mrt; switch (rule->action) { case FR_ACT_TO_TBL: break; case FR_ACT_UNREACHABLE: return -ENETUNREACH; case FR_ACT_PROHIBIT: return -EACCES; case FR_ACT_BLACKHOLE: default: return -EINVAL; } arg->table = fib_rule_get_table(rule, arg); mrt = ipmr_get_table(rule->fr_net, arg->table); if (!mrt) return -EAGAIN; res->mrt = mrt; return 0; } static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags) { return 1; } static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb, struct fib_rule_hdr *frh, struct nlattr **tb, struct netlink_ext_ack *extack) { return 0; } static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, struct nlattr **tb) { return 1; } static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb, struct fib_rule_hdr *frh) { frh->dst_len = 0; frh->src_len = 0; frh->tos = 0; return 0; } static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = { .family = RTNL_FAMILY_IPMR, .rule_size = sizeof(struct ipmr_rule), .addr_size = sizeof(u32), .action = ipmr_rule_action, .match = ipmr_rule_match, .configure = ipmr_rule_configure, .compare = ipmr_rule_compare, .fill = ipmr_rule_fill, .nlgroup = RTNLGRP_IPV4_RULE, .owner = THIS_MODULE, }; static int __net_init ipmr_rules_init(struct net *net) { struct fib_rules_ops *ops; struct mr_table *mrt; int err; ops = fib_rules_register(&ipmr_rules_ops_template, net); if (IS_ERR(ops)) return PTR_ERR(ops); INIT_LIST_HEAD(&net->ipv4.mr_tables); mrt = ipmr_new_table(net, RT_TABLE_DEFAULT); if (IS_ERR(mrt)) { err = PTR_ERR(mrt); goto err1; } err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0); if (err < 0) goto err2; net->ipv4.mr_rules_ops = ops; return 0; err2: rtnl_lock(); ipmr_free_table(mrt); rtnl_unlock(); err1: fib_rules_unregister(ops); return err; } static void __net_exit ipmr_rules_exit(struct net *net) { struct mr_table *mrt, *next; ASSERT_RTNL(); list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) { list_del(&mrt->list); ipmr_free_table(mrt); } fib_rules_unregister(net->ipv4.mr_rules_ops); } static int ipmr_rules_dump(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { return fib_rules_dump(net, nb, RTNL_FAMILY_IPMR, extack); } static unsigned int ipmr_rules_seq_read(struct net *net) { return fib_rules_seq_read(net, RTNL_FAMILY_IPMR); } bool ipmr_rule_default(const struct fib_rule *rule) { return fib_rule_matchall(rule) && rule->table == RT_TABLE_DEFAULT; } EXPORT_SYMBOL(ipmr_rule_default); #else #define ipmr_for_each_table(mrt, net) \ for (mrt = net->ipv4.mrt; mrt; mrt = NULL) static struct mr_table *ipmr_mr_table_iter(struct net *net, struct mr_table *mrt) { if (!mrt) return net->ipv4.mrt; return NULL; } static struct mr_table *ipmr_get_table(struct net *net, u32 id) { return net->ipv4.mrt; } static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4, struct mr_table **mrt) { *mrt = net->ipv4.mrt; return 0; } static int __net_init ipmr_rules_init(struct net *net) { struct mr_table *mrt; mrt = ipmr_new_table(net, RT_TABLE_DEFAULT); if (IS_ERR(mrt)) return PTR_ERR(mrt); net->ipv4.mrt = mrt; return 0; } static void __net_exit ipmr_rules_exit(struct net *net) { ASSERT_RTNL(); ipmr_free_table(net->ipv4.mrt); net->ipv4.mrt = NULL; } static int ipmr_rules_dump(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { return 0; } static unsigned int ipmr_rules_seq_read(struct net *net) { return 0; } bool ipmr_rule_default(const struct fib_rule *rule) { return true; } EXPORT_SYMBOL(ipmr_rule_default); #endif static inline int ipmr_hash_cmp(struct rhashtable_compare_arg *arg, const void *ptr) { const struct mfc_cache_cmp_arg *cmparg = arg->key; const struct mfc_cache *c = ptr; return cmparg->mfc_mcastgrp != c->mfc_mcastgrp || cmparg->mfc_origin != c->mfc_origin; } static const struct rhashtable_params ipmr_rht_params = { .head_offset = offsetof(struct mr_mfc, mnode), .key_offset = offsetof(struct mfc_cache, cmparg), .key_len = sizeof(struct mfc_cache_cmp_arg), .nelem_hint = 3, .obj_cmpfn = ipmr_hash_cmp, .automatic_shrinking = true, }; static void ipmr_new_table_set(struct mr_table *mrt, struct net *net) { #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES list_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables); #endif } static struct mfc_cache_cmp_arg ipmr_mr_table_ops_cmparg_any = { .mfc_mcastgrp = htonl(INADDR_ANY), .mfc_origin = htonl(INADDR_ANY), }; static struct mr_table_ops ipmr_mr_table_ops = { .rht_params = &ipmr_rht_params, .cmparg_any = &ipmr_mr_table_ops_cmparg_any, }; static struct mr_table *ipmr_new_table(struct net *net, u32 id) { struct mr_table *mrt; /* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) */ if (id != RT_TABLE_DEFAULT && id >= 1000000000) return ERR_PTR(-EINVAL); mrt = ipmr_get_table(net, id); if (mrt) return mrt; return mr_table_alloc(net, id, &ipmr_mr_table_ops, ipmr_expire_process, ipmr_new_table_set); } static void ipmr_free_table(struct mr_table *mrt) { timer_shutdown_sync(&mrt->ipmr_expire_timer); mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC | MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC); rhltable_destroy(&mrt->mfc_hash); kfree(mrt); } /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */ /* Initialize ipmr pimreg/tunnel in_device */ static bool ipmr_init_vif_indev(const struct net_device *dev) { struct in_device *in_dev; ASSERT_RTNL(); in_dev = __in_dev_get_rtnl(dev); if (!in_dev) return false; ipv4_devconf_setall(in_dev); neigh_parms_data_state_setall(in_dev->arp_parms); IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0; return true; } static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v) { struct net_device *tunnel_dev, *new_dev; struct ip_tunnel_parm p = { }; int err; tunnel_dev = __dev_get_by_name(net, "tunl0"); if (!tunnel_dev) goto out; p.iph.daddr = v->vifc_rmt_addr.s_addr; p.iph.saddr = v->vifc_lcl_addr.s_addr; p.iph.version = 4; p.iph.ihl = 5; p.iph.protocol = IPPROTO_IPIP; sprintf(p.name, "dvmrp%d", v->vifc_vifi); if (!tunnel_dev->netdev_ops->ndo_tunnel_ctl) goto out; err = tunnel_dev->netdev_ops->ndo_tunnel_ctl(tunnel_dev, &p, SIOCADDTUNNEL); if (err) goto out; new_dev = __dev_get_by_name(net, p.name); if (!new_dev) goto out; new_dev->flags |= IFF_MULTICAST; if (!ipmr_init_vif_indev(new_dev)) goto out_unregister; if (dev_open(new_dev, NULL)) goto out_unregister; dev_hold(new_dev); err = dev_set_allmulti(new_dev, 1); if (err) { dev_close(new_dev); tunnel_dev->netdev_ops->ndo_tunnel_ctl(tunnel_dev, &p, SIOCDELTUNNEL); dev_put(new_dev); new_dev = ERR_PTR(err); } return new_dev; out_unregister: unregister_netdevice(new_dev); out: return ERR_PTR(-ENOBUFS); } #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2) static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev) { struct net *net = dev_net(dev); struct mr_table *mrt; struct flowi4 fl4 = { .flowi4_oif = dev->ifindex, .flowi4_iif = skb->skb_iif ? : LOOPBACK_IFINDEX, .flowi4_mark = skb->mark, }; int err; err = ipmr_fib_lookup(net, &fl4, &mrt); if (err < 0) { kfree_skb(skb); return err; } DEV_STATS_ADD(dev, tx_bytes, skb->len); DEV_STATS_INC(dev, tx_packets); rcu_read_lock(); /* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */ ipmr_cache_report(mrt, skb, READ_ONCE(mrt->mroute_reg_vif_num), IGMPMSG_WHOLEPKT); rcu_read_unlock(); kfree_skb(skb); return NETDEV_TX_OK; } static int reg_vif_get_iflink(const struct net_device *dev) { return 0; } static const struct net_device_ops reg_vif_netdev_ops = { .ndo_start_xmit = reg_vif_xmit, .ndo_get_iflink = reg_vif_get_iflink, }; static void reg_vif_setup(struct net_device *dev) { dev->type = ARPHRD_PIMREG; dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 8; dev->flags = IFF_NOARP; dev->netdev_ops = &reg_vif_netdev_ops; dev->needs_free_netdev = true; dev->features |= NETIF_F_NETNS_LOCAL; } static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt) { struct net_device *dev; char name[IFNAMSIZ]; if (mrt->id == RT_TABLE_DEFAULT) sprintf(name, "pimreg"); else sprintf(name, "pimreg%u", mrt->id); dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup); if (!dev) return NULL; dev_net_set(dev, net); if (register_netdevice(dev)) { free_netdev(dev); return NULL; } if (!ipmr_init_vif_indev(dev)) goto failure; if (dev_open(dev, NULL)) goto failure; dev_hold(dev); return dev; failure: unregister_netdevice(dev); return NULL; } /* called with rcu_read_lock() */ static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb, unsigned int pimlen) { struct net_device *reg_dev = NULL; struct iphdr *encap; int vif_num; encap = (struct iphdr *)(skb_transport_header(skb) + pimlen); /* Check that: * a. packet is really sent to a multicast group * b. packet is not a NULL-REGISTER * c. packet is not truncated */ if (!ipv4_is_multicast(encap->daddr) || encap->tot_len == 0 || ntohs(encap->tot_len) + pimlen > skb->len) return 1; /* Pairs with WRITE_ONCE() in vif_add()/vid_delete() */ vif_num = READ_ONCE(mrt->mroute_reg_vif_num); if (vif_num >= 0) reg_dev = vif_dev_read(&mrt->vif_table[vif_num]); if (!reg_dev) return 1; skb->mac_header = skb->network_header; skb_pull(skb, (u8 *)encap - skb->data); skb_reset_network_header(skb); skb->protocol = htons(ETH_P_IP); skb->ip_summed = CHECKSUM_NONE; skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev)); netif_rx(skb); return NET_RX_SUCCESS; } #else static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt) { return NULL; } #endif static int call_ipmr_vif_entry_notifiers(struct net *net, enum fib_event_type event_type, struct vif_device *vif, struct net_device *vif_dev, vifi_t vif_index, u32 tb_id) { return mr_call_vif_notifiers(net, RTNL_FAMILY_IPMR, event_type, vif, vif_dev, vif_index, tb_id, &net->ipv4.ipmr_seq); } static int call_ipmr_mfc_entry_notifiers(struct net *net, enum fib_event_type event_type, struct mfc_cache *mfc, u32 tb_id) { return mr_call_mfc_notifiers(net, RTNL_FAMILY_IPMR, event_type, &mfc->_c, tb_id, &net->ipv4.ipmr_seq); } /** * vif_delete - Delete a VIF entry * @mrt: Table to delete from * @vifi: VIF identifier to delete * @notify: Set to 1, if the caller is a notifier_call * @head: if unregistering the VIF, place it on this queue */ static int vif_delete(struct mr_table *mrt, int vifi, int notify, struct list_head *head) { struct net *net = read_pnet(&mrt->net); struct vif_device *v; struct net_device *dev; struct in_device *in_dev; if (vifi < 0 || vifi >= mrt->maxvif) return -EADDRNOTAVAIL; v = &mrt->vif_table[vifi]; dev = rtnl_dereference(v->dev); if (!dev) return -EADDRNOTAVAIL; spin_lock(&mrt_lock); call_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_DEL, v, dev, vifi, mrt->id); RCU_INIT_POINTER(v->dev, NULL); if (vifi == mrt->mroute_reg_vif_num) { /* Pairs with READ_ONCE() in ipmr_cache_report() and reg_vif_xmit() */ WRITE_ONCE(mrt->mroute_reg_vif_num, -1); } if (vifi + 1 == mrt->maxvif) { int tmp; for (tmp = vifi - 1; tmp >= 0; tmp--) { if (VIF_EXISTS(mrt, tmp)) break; } WRITE_ONCE(mrt->maxvif, tmp + 1); } spin_unlock(&mrt_lock); dev_set_allmulti(dev, -1); in_dev = __in_dev_get_rtnl(dev); if (in_dev) { IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--; inet_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF, NETCONFA_MC_FORWARDING, dev->ifindex, &in_dev->cnf); ip_rt_multicast_event(in_dev); } if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify) unregister_netdevice_queue(dev, head); netdev_put(dev, &v->dev_tracker); return 0; } static void ipmr_cache_free_rcu(struct rcu_head *head) { struct mr_mfc *c = container_of(head, struct mr_mfc, rcu); kmem_cache_free(mrt_cachep, (struct mfc_cache *)c); } static void ipmr_cache_free(struct mfc_cache *c) { call_rcu(&c->_c.rcu, ipmr_cache_free_rcu); } /* Destroy an unresolved cache entry, killing queued skbs * and reporting error to netlink readers. */ static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c) { struct net *net = read_pnet(&mrt->net); struct sk_buff *skb; struct nlmsgerr *e; atomic_dec(&mrt->cache_resolve_queue_len); while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved))) { if (ip_hdr(skb)->version == 0) { struct nlmsghdr *nlh = skb_pull(skb, sizeof(struct iphdr)); nlh->nlmsg_type = NLMSG_ERROR; nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr)); skb_trim(skb, nlh->nlmsg_len); e = nlmsg_data(nlh); e->error = -ETIMEDOUT; memset(&e->msg, 0, sizeof(e->msg)); rtnl_unicast(skb, net, NETLINK_CB(skb).portid); } else { kfree_skb(skb); } } ipmr_cache_free(c); } /* Timer process for the unresolved queue. */ static void ipmr_expire_process(struct timer_list *t) { struct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer); struct mr_mfc *c, *next; unsigned long expires; unsigned long now; if (!spin_trylock(&mfc_unres_lock)) { mod_timer(&mrt->ipmr_expire_timer, jiffies+HZ/10); return; } if (list_empty(&mrt->mfc_unres_queue)) goto out; now = jiffies; expires = 10*HZ; list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) { if (time_after(c->mfc_un.unres.expires, now)) { unsigned long interval = c->mfc_un.unres.expires - now; if (interval < expires) expires = interval; continue; } list_del(&c->list); mroute_netlink_event(mrt, (struct mfc_cache *)c, RTM_DELROUTE); ipmr_destroy_unres(mrt, (struct mfc_cache *)c); } if (!list_empty(&mrt->mfc_unres_queue)) mod_timer(&mrt->ipmr_expire_timer, jiffies + expires); out: spin_unlock(&mfc_unres_lock); } /* Fill oifs list. It is called under locked mrt_lock. */ static void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache, unsigned char *ttls) { int vifi; cache->mfc_un.res.minvif = MAXVIFS; cache->mfc_un.res.maxvif = 0; memset(cache->mfc_un.res.ttls, 255, MAXVIFS); for (vifi = 0; vifi < mrt->maxvif; vifi++) { if (VIF_EXISTS(mrt, vifi) && ttls[vifi] && ttls[vifi] < 255) { cache->mfc_un.res.ttls[vifi] = ttls[vifi]; if (cache->mfc_un.res.minvif > vifi) cache->mfc_un.res.minvif = vifi; if (cache->mfc_un.res.maxvif <= vifi) cache->mfc_un.res.maxvif = vifi + 1; } } cache->mfc_un.res.lastuse = jiffies; } static int vif_add(struct net *net, struct mr_table *mrt, struct vifctl *vifc, int mrtsock) { struct netdev_phys_item_id ppid = { }; int vifi = vifc->vifc_vifi; struct vif_device *v = &mrt->vif_table[vifi]; struct net_device *dev; struct in_device *in_dev; int err; /* Is vif busy ? */ if (VIF_EXISTS(mrt, vifi)) return -EADDRINUSE; switch (vifc->vifc_flags) { case VIFF_REGISTER: if (!ipmr_pimsm_enabled()) return -EINVAL; /* Special Purpose VIF in PIM * All the packets will be sent to the daemon */ if (mrt->mroute_reg_vif_num >= 0) return -EADDRINUSE; dev = ipmr_reg_vif(net, mrt); if (!dev) return -ENOBUFS; err = dev_set_allmulti(dev, 1); if (err) { unregister_netdevice(dev); dev_put(dev); return err; } break; case VIFF_TUNNEL: dev = ipmr_new_tunnel(net, vifc); if (IS_ERR(dev)) return PTR_ERR(dev); break; case VIFF_USE_IFINDEX: case 0: if (vifc->vifc_flags == VIFF_USE_IFINDEX) { dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex); if (dev && !__in_dev_get_rtnl(dev)) { dev_put(dev); return -EADDRNOTAVAIL; } } else { dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr); } if (!dev) return -EADDRNOTAVAIL; err = dev_set_allmulti(dev, 1); if (err) { dev_put(dev); return err; } break; default: return -EINVAL; } in_dev = __in_dev_get_rtnl(dev); if (!in_dev) { dev_put(dev); return -EADDRNOTAVAIL; } IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++; inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_MC_FORWARDING, dev->ifindex, &in_dev->cnf); ip_rt_multicast_event(in_dev); /* Fill in the VIF structures */ vif_device_init(v, dev, vifc->vifc_rate_limit, vifc->vifc_threshold, vifc->vifc_flags | (!mrtsock ? VIFF_STATIC : 0), (VIFF_TUNNEL | VIFF_REGISTER)); err = dev_get_port_parent_id(dev, &ppid, true); if (err == 0) { memcpy(v->dev_parent_id.id, ppid.id, ppid.id_len); v->dev_parent_id.id_len = ppid.id_len; } else { v->dev_parent_id.id_len = 0; } v->local = vifc->vifc_lcl_addr.s_addr; v->remote = vifc->vifc_rmt_addr.s_addr; /* And finish update writing critical data */ spin_lock(&mrt_lock); rcu_assign_pointer(v->dev, dev); netdev_tracker_alloc(dev, &v->dev_tracker, GFP_ATOMIC); if (v->flags & VIFF_REGISTER) { /* Pairs with READ_ONCE() in ipmr_cache_report() and reg_vif_xmit() */ WRITE_ONCE(mrt->mroute_reg_vif_num, vifi); } if (vifi+1 > mrt->maxvif) WRITE_ONCE(mrt->maxvif, vifi + 1); spin_unlock(&mrt_lock); call_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD, v, dev, vifi, mrt->id); return 0; } /* called with rcu_read_lock() */ static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt, __be32 origin, __be32 mcastgrp) { struct mfc_cache_cmp_arg arg = { .mfc_mcastgrp = mcastgrp, .mfc_origin = origin }; return mr_mfc_find(mrt, &arg); } /* Look for a (*,G) entry */ static struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt, __be32 mcastgrp, int vifi) { struct mfc_cache_cmp_arg arg = { .mfc_mcastgrp = mcastgrp, .mfc_origin = htonl(INADDR_ANY) }; if (mcastgrp == htonl(INADDR_ANY)) return mr_mfc_find_any_parent(mrt, vifi); return mr_mfc_find_any(mrt, vifi, &arg); } /* Look for a (S,G,iif) entry if parent != -1 */ static struct mfc_cache *ipmr_cache_find_parent(struct mr_table *mrt, __be32 origin, __be32 mcastgrp, int parent) { struct mfc_cache_cmp_arg arg = { .mfc_mcastgrp = mcastgrp, .mfc_origin = origin, }; return mr_mfc_find_parent(mrt, &arg, parent); } /* Allocate a multicast cache entry */ static struct mfc_cache *ipmr_cache_alloc(void) { struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL); if (c) { c->_c.mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1; c->_c.mfc_un.res.minvif = MAXVIFS; c->_c.free = ipmr_cache_free_rcu; refcount_set(&c->_c.mfc_un.res.refcount, 1); } return c; } static struct mfc_cache *ipmr_cache_alloc_unres(void) { struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC); if (c) { skb_queue_head_init(&c->_c.mfc_un.unres.unresolved); c->_c.mfc_un.unres.expires = jiffies + 10 * HZ; } return c; } /* A cache entry has gone into a resolved state from queued */ static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt, struct mfc_cache *uc, struct mfc_cache *c) { struct sk_buff *skb; struct nlmsgerr *e; /* Play the pending entries through our router */ while ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) { if (ip_hdr(skb)->version == 0) { struct nlmsghdr *nlh = skb_pull(skb, sizeof(struct iphdr)); if (mr_fill_mroute(mrt, skb, &c->_c, nlmsg_data(nlh)) > 0) { nlh->nlmsg_len = skb_tail_pointer(skb) - (u8 *)nlh; } else { nlh->nlmsg_type = NLMSG_ERROR; nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr)); skb_trim(skb, nlh->nlmsg_len); e = nlmsg_data(nlh); e->error = -EMSGSIZE; memset(&e->msg, 0, sizeof(e->msg)); } rtnl_unicast(skb, net, NETLINK_CB(skb).portid); } else { rcu_read_lock(); ip_mr_forward(net, mrt, skb->dev, skb, c, 0); rcu_read_unlock(); } } } /* Bounce a cache query up to mrouted and netlink. * * Called under rcu_read_lock(). */ static int ipmr_cache_report(const struct mr_table *mrt, struct sk_buff *pkt, vifi_t vifi, int assert) { const int ihl = ip_hdrlen(pkt); struct sock *mroute_sk; struct igmphdr *igmp; struct igmpmsg *msg; struct sk_buff *skb; int ret; if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) skb = skb_realloc_headroom(pkt, sizeof(struct iphdr)); else skb = alloc_skb(128, GFP_ATOMIC); if (!skb) return -ENOBUFS; if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) { /* Ugly, but we have no choice with this interface. * Duplicate old header, fix ihl, length etc. * And all this only to mangle msg->im_msgtype and * to set msg->im_mbz to "mbz" :-) */ skb_push(skb, sizeof(struct iphdr)); skb_reset_network_header(skb); skb_reset_transport_header(skb); msg = (struct igmpmsg *)skb_network_header(skb); memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr)); msg->im_msgtype = assert; msg->im_mbz = 0; if (assert == IGMPMSG_WRVIFWHOLE) { msg->im_vif = vifi; msg->im_vif_hi = vifi >> 8; } else { /* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */ int vif_num = READ_ONCE(mrt->mroute_reg_vif_num); msg->im_vif = vif_num; msg->im_vif_hi = vif_num >> 8; } ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2; ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) + sizeof(struct iphdr)); } else { /* Copy the IP header */ skb_set_network_header(skb, skb->len); skb_put(skb, ihl); skb_copy_to_linear_data(skb, pkt->data, ihl); /* Flag to the kernel this is a route add */ ip_hdr(skb)->protocol = 0; msg = (struct igmpmsg *)skb_network_header(skb); msg->im_vif = vifi; msg->im_vif_hi = vifi >> 8; skb_dst_set(skb, dst_clone(skb_dst(pkt))); /* Add our header */ igmp = skb_put(skb, sizeof(struct igmphdr)); igmp->type = assert; msg->im_msgtype = assert; igmp->code = 0; ip_hdr(skb)->tot_len = htons(skb->len); /* Fix the length */ skb->transport_header = skb->network_header; } mroute_sk = rcu_dereference(mrt->mroute_sk); if (!mroute_sk) { kfree_skb(skb); return -EINVAL; } igmpmsg_netlink_event(mrt, skb); /* Deliver to mrouted */ ret = sock_queue_rcv_skb(mroute_sk, skb); if (ret < 0) { net_warn_ratelimited("mroute: pending queue full, dropping entries\n"); kfree_skb(skb); } return ret; } /* Queue a packet for resolution. It gets locked cache entry! */ /* Called under rcu_read_lock() */ static int ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi, struct sk_buff *skb, struct net_device *dev) { const struct iphdr *iph = ip_hdr(skb); struct mfc_cache *c; bool found = false; int err; spin_lock_bh(&mfc_unres_lock); list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) { if (c->mfc_mcastgrp == iph->daddr && c->mfc_origin == iph->saddr) { found = true; break; } } if (!found) { /* Create a new entry if allowable */ c = ipmr_cache_alloc_unres(); if (!c) { spin_unlock_bh(&mfc_unres_lock); kfree_skb(skb); return -ENOBUFS; } /* Fill in the new cache entry */ c->_c.mfc_parent = -1; c->mfc_origin = iph->saddr; c->mfc_mcastgrp = iph->daddr; /* Reflect first query at mrouted. */ err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE); if (err < 0) { /* If the report failed throw the cache entry out - Brad Parker */ spin_unlock_bh(&mfc_unres_lock); ipmr_cache_free(c); kfree_skb(skb); return err; } atomic_inc(&mrt->cache_resolve_queue_len); list_add(&c->_c.list, &mrt->mfc_unres_queue); mroute_netlink_event(mrt, c, RTM_NEWROUTE); if (atomic_read(&mrt->cache_resolve_queue_len) == 1) mod_timer(&mrt->ipmr_expire_timer, c->_c.mfc_un.unres.expires); } /* See if we can append the packet */ if (c->_c.mfc_un.unres.unresolved.qlen > 3) { kfree_skb(skb); err = -ENOBUFS; } else { if (dev) { skb->dev = dev; skb->skb_iif = dev->ifindex; } skb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb); err = 0; } spin_unlock_bh(&mfc_unres_lock); return err; } /* MFC cache manipulation by user space mroute daemon */ static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent) { struct net *net = read_pnet(&mrt->net); struct mfc_cache *c; /* The entries are added/deleted only under RTNL */ rcu_read_lock(); c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr, mfc->mfcc_mcastgrp.s_addr, parent); rcu_read_unlock(); if (!c) return -ENOENT; rhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ipmr_rht_params); list_del_rcu(&c->_c.list); call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, c, mrt->id); mroute_netlink_event(mrt, c, RTM_DELROUTE); mr_cache_put(&c->_c); return 0; } static int ipmr_mfc_add(struct net *net, struct mr_table *mrt, struct mfcctl *mfc, int mrtsock, int parent) { struct mfc_cache *uc, *c; struct mr_mfc *_uc; bool found; int ret; if (mfc->mfcc_parent >= MAXVIFS) return -ENFILE; /* The entries are added/deleted only under RTNL */ rcu_read_lock(); c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr, mfc->mfcc_mcastgrp.s_addr, parent); rcu_read_unlock(); if (c) { spin_lock(&mrt_lock); c->_c.mfc_parent = mfc->mfcc_parent; ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls); if (!mrtsock) c->_c.mfc_flags |= MFC_STATIC; spin_unlock(&mrt_lock); call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, c, mrt->id); mroute_netlink_event(mrt, c, RTM_NEWROUTE); return 0; } if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) && !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr)) return -EINVAL; c = ipmr_cache_alloc(); if (!c) return -ENOMEM; c->mfc_origin = mfc->mfcc_origin.s_addr; c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr; c->_c.mfc_parent = mfc->mfcc_parent; ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls); if (!mrtsock) c->_c.mfc_flags |= MFC_STATIC; ret = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode, ipmr_rht_params); if (ret) { pr_err("ipmr: rhtable insert error %d\n", ret); ipmr_cache_free(c); return ret; } list_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list); /* Check to see if we resolved a queued list. If so we * need to send on the frames and tidy up. */ found = false; spin_lock_bh(&mfc_unres_lock); list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) { uc = (struct mfc_cache *)_uc; if (uc->mfc_origin == c->mfc_origin && uc->mfc_mcastgrp == c->mfc_mcastgrp) { list_del(&_uc->list); atomic_dec(&mrt->cache_resolve_queue_len); found = true; break; } } if (list_empty(&mrt->mfc_unres_queue)) del_timer(&mrt->ipmr_expire_timer); spin_unlock_bh(&mfc_unres_lock); if (found) { ipmr_cache_resolve(net, mrt, uc, c); ipmr_cache_free(uc); } call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, c, mrt->id); mroute_netlink_event(mrt, c, RTM_NEWROUTE); return 0; } /* Close the multicast socket, and clear the vif tables etc */ static void mroute_clean_tables(struct mr_table *mrt, int flags) { struct net *net = read_pnet(&mrt->net); struct mr_mfc *c, *tmp; struct mfc_cache *cache; LIST_HEAD(list); int i; /* Shut down all active vif entries */ if (flags & (MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC)) { for (i = 0; i < mrt->maxvif; i++) { if (((mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT_FLUSH_VIFS_STATIC)) || (!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT_FLUSH_VIFS))) continue; vif_delete(mrt, i, 0, &list); } unregister_netdevice_many(&list); } /* Wipe the cache */ if (flags & (MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC)) { list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) { if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC_STATIC)) || (!(c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC))) continue; rhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params); list_del_rcu(&c->list); cache = (struct mfc_cache *)c; call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache, mrt->id); mroute_netlink_event(mrt, cache, RTM_DELROUTE); mr_cache_put(c); } } if (flags & MRT_FLUSH_MFC) { if (atomic_read(&mrt->cache_resolve_queue_len) != 0) { spin_lock_bh(&mfc_unres_lock); list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) { list_del(&c->list); cache = (struct mfc_cache *)c; mroute_netlink_event(mrt, cache, RTM_DELROUTE); ipmr_destroy_unres(mrt, cache); } spin_unlock_bh(&mfc_unres_lock); } } } /* called from ip_ra_control(), before an RCU grace period, * we don't need to call synchronize_rcu() here */ static void mrtsock_destruct(struct sock *sk) { struct net *net = sock_net(sk); struct mr_table *mrt; rtnl_lock(); ipmr_for_each_table(mrt, net) { if (sk == rtnl_dereference(mrt->mroute_sk)) { IPV4_DEVCONF_ALL(net, MC_FORWARDING)--; inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_MC_FORWARDING, NETCONFA_IFINDEX_ALL, net->ipv4.devconf_all); RCU_INIT_POINTER(mrt->mroute_sk, NULL); mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_MFC); } } rtnl_unlock(); } /* Socket options and virtual interface manipulation. The whole * virtual interface system is a complete heap, but unfortunately * that's how BSD mrouted happens to think. Maybe one day with a proper * MOSPF/PIM router set up we can clean this up. */ int ip_mroute_setsockopt(struct sock *sk, int optname, sockptr_t optval, unsigned int optlen) { struct net *net = sock_net(sk); int val, ret = 0, parent = 0; struct mr_table *mrt; struct vifctl vif; struct mfcctl mfc; bool do_wrvifwhole; u32 uval; /* There's one exception to the lock - MRT_DONE which needs to unlock */ rtnl_lock(); if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_IGMP) { ret = -EOPNOTSUPP; goto out_unlock; } mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT); if (!mrt) { ret = -ENOENT; goto out_unlock; } if (optname != MRT_INIT) { if (sk != rcu_access_pointer(mrt->mroute_sk) && !ns_capable(net->user_ns, CAP_NET_ADMIN)) { ret = -EACCES; goto out_unlock; } } switch (optname) { case MRT_INIT: if (optlen != sizeof(int)) { ret = -EINVAL; break; } if (rtnl_dereference(mrt->mroute_sk)) { ret = -EADDRINUSE; break; } ret = ip_ra_control(sk, 1, mrtsock_destruct); if (ret == 0) { rcu_assign_pointer(mrt->mroute_sk, sk); IPV4_DEVCONF_ALL(net, MC_FORWARDING)++; inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_MC_FORWARDING, NETCONFA_IFINDEX_ALL, net->ipv4.devconf_all); } break; case MRT_DONE: if (sk != rcu_access_pointer(mrt->mroute_sk)) { ret = -EACCES; } else { /* We need to unlock here because mrtsock_destruct takes * care of rtnl itself and we can't change that due to * the IP_ROUTER_ALERT setsockopt which runs without it. */ rtnl_unlock(); ret = ip_ra_control(sk, 0, NULL); goto out; } break; case MRT_ADD_VIF: case MRT_DEL_VIF: if (optlen != sizeof(vif)) { ret = -EINVAL; break; } if (copy_from_sockptr(&vif, optval, sizeof(vif))) { ret = -EFAULT; break; } if (vif.vifc_vifi >= MAXVIFS) { ret = -ENFILE; break; } if (optname == MRT_ADD_VIF) { ret = vif_add(net, mrt, &vif, sk == rtnl_dereference(mrt->mroute_sk)); } else { ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL); } break; /* Manipulate the forwarding caches. These live * in a sort of kernel/user symbiosis. */ case MRT_ADD_MFC: case MRT_DEL_MFC: parent = -1; fallthrough; case MRT_ADD_MFC_PROXY: case MRT_DEL_MFC_PROXY: if (optlen != sizeof(mfc)) { ret = -EINVAL; break; } if (copy_from_sockptr(&mfc, optval, sizeof(mfc))) { ret = -EFAULT; break; } if (parent == 0) parent = mfc.mfcc_parent; if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY) ret = ipmr_mfc_delete(mrt, &mfc, parent); else ret = ipmr_mfc_add(net, mrt, &mfc, sk == rtnl_dereference(mrt->mroute_sk), parent); break; case MRT_FLUSH: if (optlen != sizeof(val)) { ret = -EINVAL; break; } if (copy_from_sockptr(&val, optval, sizeof(val))) { ret = -EFAULT; break; } mroute_clean_tables(mrt, val); break; /* Control PIM assert. */ case MRT_ASSERT: if (optlen != sizeof(val)) { ret = -EINVAL; break; } if (copy_from_sockptr(&val, optval, sizeof(val))) { ret = -EFAULT; break; } mrt->mroute_do_assert = val; break; case MRT_PIM: if (!ipmr_pimsm_enabled()) { ret = -ENOPROTOOPT; break; } if (optlen != sizeof(val)) { ret = -EINVAL; break; } if (copy_from_sockptr(&val, optval, sizeof(val))) { ret = -EFAULT; break; } do_wrvifwhole = (val == IGMPMSG_WRVIFWHOLE); val = !!val; if (val != mrt->mroute_do_pim) { mrt->mroute_do_pim = val; mrt->mroute_do_assert = val; mrt->mroute_do_wrvifwhole = do_wrvifwhole; } break; case MRT_TABLE: if (!IS_BUILTIN(CONFIG_IP_MROUTE_MULTIPLE_TABLES)) { ret = -ENOPROTOOPT; break; } if (optlen != sizeof(uval)) { ret = -EINVAL; break; } if (copy_from_sockptr(&uval, optval, sizeof(uval))) { ret = -EFAULT; break; } if (sk == rtnl_dereference(mrt->mroute_sk)) { ret = -EBUSY; } else { mrt = ipmr_new_table(net, uval); if (IS_ERR(mrt)) ret = PTR_ERR(mrt); else raw_sk(sk)->ipmr_table = uval; } break; /* Spurious command, or MRT_VERSION which you cannot set. */ default: ret = -ENOPROTOOPT; } out_unlock: rtnl_unlock(); out: return ret; } /* Execute if this ioctl is a special mroute ioctl */ int ipmr_sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg) { switch (cmd) { /* These userspace buffers will be consumed by ipmr_ioctl() */ case SIOCGETVIFCNT: { struct sioc_vif_req buffer; return sock_ioctl_inout(sk, cmd, arg, &buffer, sizeof(buffer)); } case SIOCGETSGCNT: { struct sioc_sg_req buffer; return sock_ioctl_inout(sk, cmd, arg, &buffer, sizeof(buffer)); } } /* return code > 0 means that the ioctl was not executed */ return 1; } /* Getsock opt support for the multicast routing system. */ int ip_mroute_getsockopt(struct sock *sk, int optname, sockptr_t optval, sockptr_t optlen) { int olr; int val; struct net *net = sock_net(sk); struct mr_table *mrt; if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_IGMP) return -EOPNOTSUPP; mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT); if (!mrt) return -ENOENT; switch (optname) { case MRT_VERSION: val = 0x0305; break; case MRT_PIM: if (!ipmr_pimsm_enabled()) return -ENOPROTOOPT; val = mrt->mroute_do_pim; break; case MRT_ASSERT: val = mrt->mroute_do_assert; break; default: return -ENOPROTOOPT; } if (copy_from_sockptr(&olr, optlen, sizeof(int))) return -EFAULT; olr = min_t(unsigned int, olr, sizeof(int)); if (olr < 0) return -EINVAL; if (copy_to_sockptr(optlen, &olr, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, &val, olr)) return -EFAULT; return 0; } /* The IP multicast ioctl support routines. */ int ipmr_ioctl(struct sock *sk, int cmd, void *arg) { struct vif_device *vif; struct mfc_cache *c; struct net *net = sock_net(sk); struct sioc_vif_req *vr; struct sioc_sg_req *sr; struct mr_table *mrt; mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT); if (!mrt) return -ENOENT; switch (cmd) { case SIOCGETVIFCNT: vr = (struct sioc_vif_req *)arg; if (vr->vifi >= mrt->maxvif) return -EINVAL; vr->vifi = array_index_nospec(vr->vifi, mrt->maxvif); rcu_read_lock(); vif = &mrt->vif_table[vr->vifi]; if (VIF_EXISTS(mrt, vr->vifi)) { vr->icount = READ_ONCE(vif->pkt_in); vr->ocount = READ_ONCE(vif->pkt_out); vr->ibytes = READ_ONCE(vif->bytes_in); vr->obytes = READ_ONCE(vif->bytes_out); rcu_read_unlock(); return 0; } rcu_read_unlock(); return -EADDRNOTAVAIL; case SIOCGETSGCNT: sr = (struct sioc_sg_req *)arg; rcu_read_lock(); c = ipmr_cache_find(mrt, sr->src.s_addr, sr->grp.s_addr); if (c) { sr->pktcnt = c->_c.mfc_un.res.pkt; sr->bytecnt = c->_c.mfc_un.res.bytes; sr->wrong_if = c->_c.mfc_un.res.wrong_if; rcu_read_unlock(); return 0; } rcu_read_unlock(); return -EADDRNOTAVAIL; default: return -ENOIOCTLCMD; } } #ifdef CONFIG_COMPAT struct compat_sioc_sg_req { struct in_addr src; struct in_addr grp; compat_ulong_t pktcnt; compat_ulong_t bytecnt; compat_ulong_t wrong_if; }; struct compat_sioc_vif_req { vifi_t vifi; /* Which iface */ compat_ulong_t icount; compat_ulong_t ocount; compat_ulong_t ibytes; compat_ulong_t obytes; }; int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg) { struct compat_sioc_sg_req sr; struct compat_sioc_vif_req vr; struct vif_device *vif; struct mfc_cache *c; struct net *net = sock_net(sk); struct mr_table *mrt; mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT); if (!mrt) return -ENOENT; switch (cmd) { case SIOCGETVIFCNT: if (copy_from_user(&vr, arg, sizeof(vr))) return -EFAULT; if (vr.vifi >= mrt->maxvif) return -EINVAL; vr.vifi = array_index_nospec(vr.vifi, mrt->maxvif); rcu_read_lock(); vif = &mrt->vif_table[vr.vifi]; if (VIF_EXISTS(mrt, vr.vifi)) { vr.icount = READ_ONCE(vif->pkt_in); vr.ocount = READ_ONCE(vif->pkt_out); vr.ibytes = READ_ONCE(vif->bytes_in); vr.obytes = READ_ONCE(vif->bytes_out); rcu_read_unlock(); if (copy_to_user(arg, &vr, sizeof(vr))) return -EFAULT; return 0; } rcu_read_unlock(); return -EADDRNOTAVAIL; case SIOCGETSGCNT: if (copy_from_user(&sr, arg, sizeof(sr))) return -EFAULT; rcu_read_lock(); c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr); if (c) { sr.pktcnt = c->_c.mfc_un.res.pkt; sr.bytecnt = c->_c.mfc_un.res.bytes; sr.wrong_if = c->_c.mfc_un.res.wrong_if; rcu_read_unlock(); if (copy_to_user(arg, &sr, sizeof(sr))) return -EFAULT; return 0; } rcu_read_unlock(); return -EADDRNOTAVAIL; default: return -ENOIOCTLCMD; } } #endif static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct net *net = dev_net(dev); struct mr_table *mrt; struct vif_device *v; int ct; if (event != NETDEV_UNREGISTER) return NOTIFY_DONE; ipmr_for_each_table(mrt, net) { v = &mrt->vif_table[0]; for (ct = 0; ct < mrt->maxvif; ct++, v++) { if (rcu_access_pointer(v->dev) == dev) vif_delete(mrt, ct, 1, NULL); } } return NOTIFY_DONE; } static struct notifier_block ip_mr_notifier = { .notifier_call = ipmr_device_event, }; /* Encapsulate a packet by attaching a valid IPIP header to it. * This avoids tunnel drivers and other mess and gives us the speed so * important for multicast video. */ static void ip_encap(struct net *net, struct sk_buff *skb, __be32 saddr, __be32 daddr) { struct iphdr *iph; const struct iphdr *old_iph = ip_hdr(skb); skb_push(skb, sizeof(struct iphdr)); skb->transport_header = skb->network_header; skb_reset_network_header(skb); iph = ip_hdr(skb); iph->version = 4; iph->tos = old_iph->tos; iph->ttl = old_iph->ttl; iph->frag_off = 0; iph->daddr = daddr; iph->saddr = saddr; iph->protocol = IPPROTO_IPIP; iph->ihl = 5; iph->tot_len = htons(skb->len); ip_select_ident(net, skb, NULL); ip_send_check(iph); memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); nf_reset_ct(skb); } static inline int ipmr_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { struct ip_options *opt = &(IPCB(skb)->opt); IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS); if (unlikely(opt->optlen)) ip_forward_options(skb); return dst_output(net, sk, skb); } #ifdef CONFIG_NET_SWITCHDEV static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt, int in_vifi, int out_vifi) { struct vif_device *out_vif = &mrt->vif_table[out_vifi]; struct vif_device *in_vif = &mrt->vif_table[in_vifi]; if (!skb->offload_l3_fwd_mark) return false; if (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len) return false; return netdev_phys_item_id_same(&out_vif->dev_parent_id, &in_vif->dev_parent_id); } #else static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt, int in_vifi, int out_vifi) { return false; } #endif /* Processing handlers for ipmr_forward, under rcu_read_lock() */ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt, int in_vifi, struct sk_buff *skb, int vifi) { const struct iphdr *iph = ip_hdr(skb); struct vif_device *vif = &mrt->vif_table[vifi]; struct net_device *vif_dev; struct net_device *dev; struct rtable *rt; struct flowi4 fl4; int encap = 0; vif_dev = vif_dev_read(vif); if (!vif_dev) goto out_free; if (vif->flags & VIFF_REGISTER) { WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1); WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len); DEV_STATS_ADD(vif_dev, tx_bytes, skb->len); DEV_STATS_INC(vif_dev, tx_packets); ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT); goto out_free; } if (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi)) goto out_free; if (vif->flags & VIFF_TUNNEL) { rt = ip_route_output_ports(net, &fl4, NULL, vif->remote, vif->local, 0, 0, IPPROTO_IPIP, RT_TOS(iph->tos), vif->link); if (IS_ERR(rt)) goto out_free; encap = sizeof(struct iphdr); } else { rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0, 0, 0, IPPROTO_IPIP, RT_TOS(iph->tos), vif->link); if (IS_ERR(rt)) goto out_free; } dev = rt->dst.dev; if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) { /* Do not fragment multicasts. Alas, IPv4 does not * allow to send ICMP, so that packets will disappear * to blackhole. */ IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS); ip_rt_put(rt); goto out_free; } encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len; if (skb_cow(skb, encap)) { ip_rt_put(rt); goto out_free; } WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1); WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len); skb_dst_drop(skb); skb_dst_set(skb, &rt->dst); ip_decrease_ttl(ip_hdr(skb)); /* FIXME: forward and output firewalls used to be called here. * What do we do with netfilter? -- RR */ if (vif->flags & VIFF_TUNNEL) { ip_encap(net, skb, vif->local, vif->remote); /* FIXME: extra output firewall step used to be here. --RR */ DEV_STATS_INC(vif_dev, tx_packets); DEV_STATS_ADD(vif_dev, tx_bytes, skb->len); } IPCB(skb)->flags |= IPSKB_FORWARDED; /* RFC1584 teaches, that DVMRP/PIM router must deliver packets locally * not only before forwarding, but after forwarding on all output * interfaces. It is clear, if mrouter runs a multicasting * program, it should receive packets not depending to what interface * program is joined. * If we will not make it, the program will have to join on all * interfaces. On the other hand, multihoming host (or router, but * not mrouter) cannot join to more than one interface - it will * result in receiving multiple packets. */ NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD, net, NULL, skb, skb->dev, dev, ipmr_forward_finish); return; out_free: kfree_skb(skb); } /* Called with mrt_lock or rcu_read_lock() */ static int ipmr_find_vif(const struct mr_table *mrt, struct net_device *dev) { int ct; /* Pairs with WRITE_ONCE() in vif_delete()/vif_add() */ for (ct = READ_ONCE(mrt->maxvif) - 1; ct >= 0; ct--) { if (rcu_access_pointer(mrt->vif_table[ct].dev) == dev) break; } return ct; } /* "local" means that we should preserve one skb (for local delivery) */ /* Called uner rcu_read_lock() */ static void ip_mr_forward(struct net *net, struct mr_table *mrt, struct net_device *dev, struct sk_buff *skb, struct mfc_cache *c, int local) { int true_vifi = ipmr_find_vif(mrt, dev); int psend = -1; int vif, ct; vif = c->_c.mfc_parent; c->_c.mfc_un.res.pkt++; c->_c.mfc_un.res.bytes += skb->len; c->_c.mfc_un.res.lastuse = jiffies; if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) { struct mfc_cache *cache_proxy; /* For an (*,G) entry, we only check that the incoming * interface is part of the static tree. */ cache_proxy = mr_mfc_find_any_parent(mrt, vif); if (cache_proxy && cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255) goto forward; } /* Wrong interface: drop packet and (maybe) send PIM assert. */ if (rcu_access_pointer(mrt->vif_table[vif].dev) != dev) { if (rt_is_output_route(skb_rtable(skb))) { /* It is our own packet, looped back. * Very complicated situation... * * The best workaround until routing daemons will be * fixed is not to redistribute packet, if it was * send through wrong interface. It means, that * multicast applications WILL NOT work for * (S,G), which have default multicast route pointing * to wrong oif. In any case, it is not a good * idea to use multicasting applications on router. */ goto dont_forward; } c->_c.mfc_un.res.wrong_if++; if (true_vifi >= 0 && mrt->mroute_do_assert && /* pimsm uses asserts, when switching from RPT to SPT, * so that we cannot check that packet arrived on an oif. * It is bad, but otherwise we would need to move pretty * large chunk of pimd to kernel. Ough... --ANK */ (mrt->mroute_do_pim || c->_c.mfc_un.res.ttls[true_vifi] < 255) && time_after(jiffies, c->_c.mfc_un.res.last_assert + MFC_ASSERT_THRESH)) { c->_c.mfc_un.res.last_assert = jiffies; ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF); if (mrt->mroute_do_wrvifwhole) ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRVIFWHOLE); } goto dont_forward; } forward: WRITE_ONCE(mrt->vif_table[vif].pkt_in, mrt->vif_table[vif].pkt_in + 1); WRITE_ONCE(mrt->vif_table[vif].bytes_in, mrt->vif_table[vif].bytes_in + skb->len); /* Forward the frame */ if (c->mfc_origin == htonl(INADDR_ANY) && c->mfc_mcastgrp == htonl(INADDR_ANY)) { if (true_vifi >= 0 && true_vifi != c->_c.mfc_parent && ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) { /* It's an (*,*) entry and the packet is not coming from * the upstream: forward the packet to the upstream * only. */ psend = c->_c.mfc_parent; goto last_forward; } goto dont_forward; } for (ct = c->_c.mfc_un.res.maxvif - 1; ct >= c->_c.mfc_un.res.minvif; ct--) { /* For (*,G) entry, don't forward to the incoming interface */ if ((c->mfc_origin != htonl(INADDR_ANY) || ct != true_vifi) && ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[ct]) { if (psend != -1) { struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) ipmr_queue_xmit(net, mrt, true_vifi, skb2, psend); } psend = ct; } } last_forward: if (psend != -1) { if (local) { struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) ipmr_queue_xmit(net, mrt, true_vifi, skb2, psend); } else { ipmr_queue_xmit(net, mrt, true_vifi, skb, psend); return; } } dont_forward: if (!local) kfree_skb(skb); } static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb) { struct rtable *rt = skb_rtable(skb); struct iphdr *iph = ip_hdr(skb); struct flowi4 fl4 = { .daddr = iph->daddr, .saddr = iph->saddr, .flowi4_tos = RT_TOS(iph->tos), .flowi4_oif = (rt_is_output_route(rt) ? skb->dev->ifindex : 0), .flowi4_iif = (rt_is_output_route(rt) ? LOOPBACK_IFINDEX : skb->dev->ifindex), .flowi4_mark = skb->mark, }; struct mr_table *mrt; int err; err = ipmr_fib_lookup(net, &fl4, &mrt); if (err) return ERR_PTR(err); return mrt; } /* Multicast packets for forwarding arrive here * Called with rcu_read_lock(); */ int ip_mr_input(struct sk_buff *skb) { struct mfc_cache *cache; struct net *net = dev_net(skb->dev); int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL; struct mr_table *mrt; struct net_device *dev; /* skb->dev passed in is the loX master dev for vrfs. * As there are no vifs associated with loopback devices, * get the proper interface that does have a vif associated with it. */ dev = skb->dev; if (netif_is_l3_master(skb->dev)) { dev = dev_get_by_index_rcu(net, IPCB(skb)->iif); if (!dev) { kfree_skb(skb); return -ENODEV; } } /* Packet is looped back after forward, it should not be * forwarded second time, but still can be delivered locally. */ if (IPCB(skb)->flags & IPSKB_FORWARDED) goto dont_forward; mrt = ipmr_rt_fib_lookup(net, skb); if (IS_ERR(mrt)) { kfree_skb(skb); return PTR_ERR(mrt); } if (!local) { if (IPCB(skb)->opt.router_alert) { if (ip_call_ra_chain(skb)) return 0; } else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) { /* IGMPv1 (and broken IGMPv2 implementations sort of * Cisco IOS <= 11.2(8)) do not put router alert * option to IGMP packets destined to routable * groups. It is very bad, because it means * that we can forward NO IGMP messages. */ struct sock *mroute_sk; mroute_sk = rcu_dereference(mrt->mroute_sk); if (mroute_sk) { nf_reset_ct(skb); raw_rcv(mroute_sk, skb); return 0; } } } /* already under rcu_read_lock() */ cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr); if (!cache) { int vif = ipmr_find_vif(mrt, dev); if (vif >= 0) cache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr, vif); } /* No usable cache entry */ if (!cache) { int vif; if (local) { struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); ip_local_deliver(skb); if (!skb2) return -ENOBUFS; skb = skb2; } vif = ipmr_find_vif(mrt, dev); if (vif >= 0) return ipmr_cache_unresolved(mrt, vif, skb, dev); kfree_skb(skb); return -ENODEV; } ip_mr_forward(net, mrt, dev, skb, cache, local); if (local) return ip_local_deliver(skb); return 0; dont_forward: if (local) return ip_local_deliver(skb); kfree_skb(skb); return 0; } #ifdef CONFIG_IP_PIMSM_V1 /* Handle IGMP messages of PIMv1 */ int pim_rcv_v1(struct sk_buff *skb) { struct igmphdr *pim; struct net *net = dev_net(skb->dev); struct mr_table *mrt; if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr))) goto drop; pim = igmp_hdr(skb); mrt = ipmr_rt_fib_lookup(net, skb); if (IS_ERR(mrt)) goto drop; if (!mrt->mroute_do_pim || pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER) goto drop; if (__pim_rcv(mrt, skb, sizeof(*pim))) { drop: kfree_skb(skb); } return 0; } #endif #ifdef CONFIG_IP_PIMSM_V2 static int pim_rcv(struct sk_buff *skb) { struct pimreghdr *pim; struct net *net = dev_net(skb->dev); struct mr_table *mrt; if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr))) goto drop; pim = (struct pimreghdr *)skb_transport_header(skb); if (pim->type != ((PIM_VERSION << 4) | (PIM_TYPE_REGISTER)) || (pim->flags & PIM_NULL_REGISTER) || (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 && csum_fold(skb_checksum(skb, 0, skb->len, 0)))) goto drop; mrt = ipmr_rt_fib_lookup(net, skb); if (IS_ERR(mrt)) goto drop; if (__pim_rcv(mrt, skb, sizeof(*pim))) { drop: kfree_skb(skb); } return 0; } #endif int ipmr_get_route(struct net *net, struct sk_buff *skb, __be32 saddr, __be32 daddr, struct rtmsg *rtm, u32 portid) { struct mfc_cache *cache; struct mr_table *mrt; int err; mrt = ipmr_get_table(net, RT_TABLE_DEFAULT); if (!mrt) return -ENOENT; rcu_read_lock(); cache = ipmr_cache_find(mrt, saddr, daddr); if (!cache && skb->dev) { int vif = ipmr_find_vif(mrt, skb->dev); if (vif >= 0) cache = ipmr_cache_find_any(mrt, daddr, vif); } if (!cache) { struct sk_buff *skb2; struct iphdr *iph; struct net_device *dev; int vif = -1; dev = skb->dev; if (dev) vif = ipmr_find_vif(mrt, dev); if (vif < 0) { rcu_read_unlock(); return -ENODEV; } skb2 = skb_realloc_headroom(skb, sizeof(struct iphdr)); if (!skb2) { rcu_read_unlock(); return -ENOMEM; } NETLINK_CB(skb2).portid = portid; skb_push(skb2, sizeof(struct iphdr)); skb_reset_network_header(skb2); iph = ip_hdr(skb2); iph->ihl = sizeof(struct iphdr) >> 2; iph->saddr = saddr; iph->daddr = daddr; iph->version = 0; err = ipmr_cache_unresolved(mrt, vif, skb2, dev); rcu_read_unlock(); return err; } err = mr_fill_mroute(mrt, skb, &cache->_c, rtm); rcu_read_unlock(); return err; } static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb, u32 portid, u32 seq, struct mfc_cache *c, int cmd, int flags) { struct nlmsghdr *nlh; struct rtmsg *rtm; int err; nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags); if (!nlh) return -EMSGSIZE; rtm = nlmsg_data(nlh); rtm->rtm_family = RTNL_FAMILY_IPMR; rtm->rtm_dst_len = 32; rtm->rtm_src_len = 32; rtm->rtm_tos = 0; rtm->rtm_table = mrt->id; if (nla_put_u32(skb, RTA_TABLE, mrt->id)) goto nla_put_failure; rtm->rtm_type = RTN_MULTICAST; rtm->rtm_scope = RT_SCOPE_UNIVERSE; if (c->_c.mfc_flags & MFC_STATIC) rtm->rtm_protocol = RTPROT_STATIC; else rtm->rtm_protocol = RTPROT_MROUTED; rtm->rtm_flags = 0; if (nla_put_in_addr(skb, RTA_SRC, c->mfc_origin) || nla_put_in_addr(skb, RTA_DST, c->mfc_mcastgrp)) goto nla_put_failure; err = mr_fill_mroute(mrt, skb, &c->_c, rtm); /* do not break the dump if cache is unresolved */ if (err < 0 && err != -ENOENT) goto nla_put_failure; nlmsg_end(skb, nlh); return 0; nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static int _ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb, u32 portid, u32 seq, struct mr_mfc *c, int cmd, int flags) { return ipmr_fill_mroute(mrt, skb, portid, seq, (struct mfc_cache *)c, cmd, flags); } static size_t mroute_msgsize(bool unresolved, int maxvif) { size_t len = NLMSG_ALIGN(sizeof(struct rtmsg)) + nla_total_size(4) /* RTA_TABLE */ + nla_total_size(4) /* RTA_SRC */ + nla_total_size(4) /* RTA_DST */ ; if (!unresolved) len = len + nla_total_size(4) /* RTA_IIF */ + nla_total_size(0) /* RTA_MULTIPATH */ + maxvif * NLA_ALIGN(sizeof(struct rtnexthop)) /* RTA_MFC_STATS */ + nla_total_size_64bit(sizeof(struct rta_mfc_stats)) ; return len; } static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc, int cmd) { struct net *net = read_pnet(&mrt->net); struct sk_buff *skb; int err = -ENOBUFS; skb = nlmsg_new(mroute_msgsize(mfc->_c.mfc_parent >= MAXVIFS, mrt->maxvif), GFP_ATOMIC); if (!skb) goto errout; err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0); if (err < 0) goto errout; rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC); return; errout: kfree_skb(skb); if (err < 0) rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err); } static size_t igmpmsg_netlink_msgsize(size_t payloadlen) { size_t len = NLMSG_ALIGN(sizeof(struct rtgenmsg)) + nla_total_size(1) /* IPMRA_CREPORT_MSGTYPE */ + nla_total_size(4) /* IPMRA_CREPORT_VIF_ID */ + nla_total_size(4) /* IPMRA_CREPORT_SRC_ADDR */ + nla_total_size(4) /* IPMRA_CREPORT_DST_ADDR */ + nla_total_size(4) /* IPMRA_CREPORT_TABLE */ /* IPMRA_CREPORT_PKT */ + nla_total_size(payloadlen) ; return len; } static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt) { struct net *net = read_pnet(&mrt->net); struct nlmsghdr *nlh; struct rtgenmsg *rtgenm; struct igmpmsg *msg; struct sk_buff *skb; struct nlattr *nla; int payloadlen; payloadlen = pkt->len - sizeof(struct igmpmsg); msg = (struct igmpmsg *)skb_network_header(pkt); skb = nlmsg_new(igmpmsg_netlink_msgsize(payloadlen), GFP_ATOMIC); if (!skb) goto errout; nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT, sizeof(struct rtgenmsg), 0); if (!nlh) goto errout; rtgenm = nlmsg_data(nlh); rtgenm->rtgen_family = RTNL_FAMILY_IPMR; if (nla_put_u8(skb, IPMRA_CREPORT_MSGTYPE, msg->im_msgtype) || nla_put_u32(skb, IPMRA_CREPORT_VIF_ID, msg->im_vif | (msg->im_vif_hi << 8)) || nla_put_in_addr(skb, IPMRA_CREPORT_SRC_ADDR, msg->im_src.s_addr) || nla_put_in_addr(skb, IPMRA_CREPORT_DST_ADDR, msg->im_dst.s_addr) || nla_put_u32(skb, IPMRA_CREPORT_TABLE, mrt->id)) goto nla_put_failure; nla = nla_reserve(skb, IPMRA_CREPORT_PKT, payloadlen); if (!nla || skb_copy_bits(pkt, sizeof(struct igmpmsg), nla_data(nla), payloadlen)) goto nla_put_failure; nlmsg_end(skb, nlh); rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC); return; nla_put_failure: nlmsg_cancel(skb, nlh); errout: kfree_skb(skb); rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS); } static int ipmr_rtm_valid_getroute_req(struct sk_buff *skb, const struct nlmsghdr *nlh, struct nlattr **tb, struct netlink_ext_ack *extack) { struct rtmsg *rtm; int i, err; if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) { NL_SET_ERR_MSG(extack, "ipv4: Invalid header for multicast route get request"); return -EINVAL; } if (!netlink_strict_get_check(skb)) return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy, extack); rtm = nlmsg_data(nlh); if ((rtm->rtm_src_len && rtm->rtm_src_len != 32) || (rtm->rtm_dst_len && rtm->rtm_dst_len != 32) || rtm->rtm_tos || rtm->rtm_table || rtm->rtm_protocol || rtm->rtm_scope || rtm->rtm_type || rtm->rtm_flags) { NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for multicast route get request"); return -EINVAL; } err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy, extack); if (err) return err; if ((tb[RTA_SRC] && !rtm->rtm_src_len) || (tb[RTA_DST] && !rtm->rtm_dst_len)) { NL_SET_ERR_MSG(extack, "ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4"); return -EINVAL; } for (i = 0; i <= RTA_MAX; i++) { if (!tb[i]) continue; switch (i) { case RTA_SRC: case RTA_DST: case RTA_TABLE: break; default: NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in multicast route get request"); return -EINVAL; } } return 0; } static int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(in_skb->sk); struct nlattr *tb[RTA_MAX + 1]; struct sk_buff *skb = NULL; struct mfc_cache *cache; struct mr_table *mrt; __be32 src, grp; u32 tableid; int err; err = ipmr_rtm_valid_getroute_req(in_skb, nlh, tb, extack); if (err < 0) goto errout; src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0; grp = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0; tableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0; mrt = ipmr_get_table(net, tableid ? tableid : RT_TABLE_DEFAULT); if (!mrt) { err = -ENOENT; goto errout_free; } /* entries are added/deleted only under RTNL */ rcu_read_lock(); cache = ipmr_cache_find(mrt, src, grp); rcu_read_unlock(); if (!cache) { err = -ENOENT; goto errout_free; } skb = nlmsg_new(mroute_msgsize(false, mrt->maxvif), GFP_KERNEL); if (!skb) { err = -ENOBUFS; goto errout_free; } err = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, cache, RTM_NEWROUTE, 0); if (err < 0) goto errout_free; err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); errout: return err; errout_free: kfree_skb(skb); goto errout; } static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb) { struct fib_dump_filter filter = {}; int err; if (cb->strict_check) { err = ip_valid_fib_dump_req(sock_net(skb->sk), cb->nlh, &filter, cb); if (err < 0) return err; } if (filter.table_id) { struct mr_table *mrt; mrt = ipmr_get_table(sock_net(skb->sk), filter.table_id); if (!mrt) { if (rtnl_msg_family(cb->nlh) != RTNL_FAMILY_IPMR) return skb->len; NL_SET_ERR_MSG(cb->extack, "ipv4: MR table does not exist"); return -ENOENT; } err = mr_table_dump(mrt, skb, cb, _ipmr_fill_mroute, &mfc_unres_lock, &filter); return skb->len ? : err; } return mr_rtm_dumproute(skb, cb, ipmr_mr_table_iter, _ipmr_fill_mroute, &mfc_unres_lock, &filter); } static const struct nla_policy rtm_ipmr_policy[RTA_MAX + 1] = { [RTA_SRC] = { .type = NLA_U32 }, [RTA_DST] = { .type = NLA_U32 }, [RTA_IIF] = { .type = NLA_U32 }, [RTA_TABLE] = { .type = NLA_U32 }, [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, }; static bool ipmr_rtm_validate_proto(unsigned char rtm_protocol) { switch (rtm_protocol) { case RTPROT_STATIC: case RTPROT_MROUTED: return true; } return false; } static int ipmr_nla_get_ttls(const struct nlattr *nla, struct mfcctl *mfcc) { struct rtnexthop *rtnh = nla_data(nla); int remaining = nla_len(nla), vifi = 0; while (rtnh_ok(rtnh, remaining)) { mfcc->mfcc_ttls[vifi] = rtnh->rtnh_hops; if (++vifi == MAXVIFS) break; rtnh = rtnh_next(rtnh, &remaining); } return remaining > 0 ? -EINVAL : vifi; } /* returns < 0 on error, 0 for ADD_MFC and 1 for ADD_MFC_PROXY */ static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh, struct mfcctl *mfcc, int *mrtsock, struct mr_table **mrtret, struct netlink_ext_ack *extack) { struct net_device *dev = NULL; u32 tblid = RT_TABLE_DEFAULT; struct mr_table *mrt; struct nlattr *attr; struct rtmsg *rtm; int ret, rem; ret = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX, rtm_ipmr_policy, extack); if (ret < 0) goto out; rtm = nlmsg_data(nlh); ret = -EINVAL; if (rtm->rtm_family != RTNL_FAMILY_IPMR || rtm->rtm_dst_len != 32 || rtm->rtm_type != RTN_MULTICAST || rtm->rtm_scope != RT_SCOPE_UNIVERSE || !ipmr_rtm_validate_proto(rtm->rtm_protocol)) goto out; memset(mfcc, 0, sizeof(*mfcc)); mfcc->mfcc_parent = -1; ret = 0; nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), rem) { switch (nla_type(attr)) { case RTA_SRC: mfcc->mfcc_origin.s_addr = nla_get_be32(attr); break; case RTA_DST: mfcc->mfcc_mcastgrp.s_addr = nla_get_be32(attr); break; case RTA_IIF: dev = __dev_get_by_index(net, nla_get_u32(attr)); if (!dev) { ret = -ENODEV; goto out; } break; case RTA_MULTIPATH: if (ipmr_nla_get_ttls(attr, mfcc) < 0) { ret = -EINVAL; goto out; } break; case RTA_PREFSRC: ret = 1; break; case RTA_TABLE: tblid = nla_get_u32(attr); break; } } mrt = ipmr_get_table(net, tblid); if (!mrt) { ret = -ENOENT; goto out; } *mrtret = mrt; *mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0; if (dev) mfcc->mfcc_parent = ipmr_find_vif(mrt, dev); out: return ret; } /* takes care of both newroute and delroute */ static int ipmr_rtm_route(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); int ret, mrtsock, parent; struct mr_table *tbl; struct mfcctl mfcc; mrtsock = 0; tbl = NULL; ret = rtm_to_ipmr_mfcc(net, nlh, &mfcc, &mrtsock, &tbl, extack); if (ret < 0) return ret; parent = ret ? mfcc.mfcc_parent : -1; if (nlh->nlmsg_type == RTM_NEWROUTE) return ipmr_mfc_add(net, tbl, &mfcc, mrtsock, parent); else return ipmr_mfc_delete(tbl, &mfcc, parent); } static bool ipmr_fill_table(struct mr_table *mrt, struct sk_buff *skb) { u32 queue_len = atomic_read(&mrt->cache_resolve_queue_len); if (nla_put_u32(skb, IPMRA_TABLE_ID, mrt->id) || nla_put_u32(skb, IPMRA_TABLE_CACHE_RES_QUEUE_LEN, queue_len) || nla_put_s32(skb, IPMRA_TABLE_MROUTE_REG_VIF_NUM, mrt->mroute_reg_vif_num) || nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_ASSERT, mrt->mroute_do_assert) || nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_PIM, mrt->mroute_do_pim) || nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_WRVIFWHOLE, mrt->mroute_do_wrvifwhole)) return false; return true; } static bool ipmr_fill_vif(struct mr_table *mrt, u32 vifid, struct sk_buff *skb) { struct net_device *vif_dev; struct nlattr *vif_nest; struct vif_device *vif; vif = &mrt->vif_table[vifid]; vif_dev = rtnl_dereference(vif->dev); /* if the VIF doesn't exist just continue */ if (!vif_dev) return true; vif_nest = nla_nest_start_noflag(skb, IPMRA_VIF); if (!vif_nest) return false; if (nla_put_u32(skb, IPMRA_VIFA_IFINDEX, vif_dev->ifindex) || nla_put_u32(skb, IPMRA_VIFA_VIF_ID, vifid) || nla_put_u16(skb, IPMRA_VIFA_FLAGS, vif->flags) || nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_IN, vif->bytes_in, IPMRA_VIFA_PAD) || nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_OUT, vif->bytes_out, IPMRA_VIFA_PAD) || nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_IN, vif->pkt_in, IPMRA_VIFA_PAD) || nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_OUT, vif->pkt_out, IPMRA_VIFA_PAD) || nla_put_be32(skb, IPMRA_VIFA_LOCAL_ADDR, vif->local) || nla_put_be32(skb, IPMRA_VIFA_REMOTE_ADDR, vif->remote)) { nla_nest_cancel(skb, vif_nest); return false; } nla_nest_end(skb, vif_nest); return true; } static int ipmr_valid_dumplink(const struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct ifinfomsg *ifm; if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) { NL_SET_ERR_MSG(extack, "ipv4: Invalid header for ipmr link dump"); return -EINVAL; } if (nlmsg_attrlen(nlh, sizeof(*ifm))) { NL_SET_ERR_MSG(extack, "Invalid data after header in ipmr link dump"); return -EINVAL; } ifm = nlmsg_data(nlh); if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags || ifm->ifi_change || ifm->ifi_index) { NL_SET_ERR_MSG(extack, "Invalid values in header for ipmr link dump request"); return -EINVAL; } return 0; } static int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback *cb) { struct net *net = sock_net(skb->sk); struct nlmsghdr *nlh = NULL; unsigned int t = 0, s_t; unsigned int e = 0, s_e; struct mr_table *mrt; if (cb->strict_check) { int err = ipmr_valid_dumplink(cb->nlh, cb->extack); if (err < 0) return err; } s_t = cb->args[0]; s_e = cb->args[1]; ipmr_for_each_table(mrt, net) { struct nlattr *vifs, *af; struct ifinfomsg *hdr; u32 i; if (t < s_t) goto skip_table; nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, RTM_NEWLINK, sizeof(*hdr), NLM_F_MULTI); if (!nlh) break; hdr = nlmsg_data(nlh); memset(hdr, 0, sizeof(*hdr)); hdr->ifi_family = RTNL_FAMILY_IPMR; af = nla_nest_start_noflag(skb, IFLA_AF_SPEC); if (!af) { nlmsg_cancel(skb, nlh); goto out; } if (!ipmr_fill_table(mrt, skb)) { nlmsg_cancel(skb, nlh); goto out; } vifs = nla_nest_start_noflag(skb, IPMRA_TABLE_VIFS); if (!vifs) { nla_nest_end(skb, af); nlmsg_end(skb, nlh); goto out; } for (i = 0; i < mrt->maxvif; i++) { if (e < s_e) goto skip_entry; if (!ipmr_fill_vif(mrt, i, skb)) { nla_nest_end(skb, vifs); nla_nest_end(skb, af); nlmsg_end(skb, nlh); goto out; } skip_entry: e++; } s_e = 0; e = 0; nla_nest_end(skb, vifs); nla_nest_end(skb, af); nlmsg_end(skb, nlh); skip_table: t++; } out: cb->args[1] = e; cb->args[0] = t; return skb->len; } #ifdef CONFIG_PROC_FS /* The /proc interfaces to multicast routing : * /proc/net/ip_mr_cache & /proc/net/ip_mr_vif */ static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos) __acquires(RCU) { struct mr_vif_iter *iter = seq->private; struct net *net = seq_file_net(seq); struct mr_table *mrt; mrt = ipmr_get_table(net, RT_TABLE_DEFAULT); if (!mrt) return ERR_PTR(-ENOENT); iter->mrt = mrt; rcu_read_lock(); return mr_vif_seq_start(seq, pos); } static void ipmr_vif_seq_stop(struct seq_file *seq, void *v) __releases(RCU) { rcu_read_unlock(); } static int ipmr_vif_seq_show(struct seq_file *seq, void *v) { struct mr_vif_iter *iter = seq->private; struct mr_table *mrt = iter->mrt; if (v == SEQ_START_TOKEN) { seq_puts(seq, "Interface BytesIn PktsIn BytesOut PktsOut Flags Local Remote\n"); } else { const struct vif_device *vif = v; const struct net_device *vif_dev; const char *name; vif_dev = vif_dev_read(vif); name = vif_dev ? vif_dev->name : "none"; seq_printf(seq, "%2td %-10s %8ld %7ld %8ld %7ld %05X %08X %08X\n", vif - mrt->vif_table, name, vif->bytes_in, vif->pkt_in, vif->bytes_out, vif->pkt_out, vif->flags, vif->local, vif->remote); } return 0; } static const struct seq_operations ipmr_vif_seq_ops = { .start = ipmr_vif_seq_start, .next = mr_vif_seq_next, .stop = ipmr_vif_seq_stop, .show = ipmr_vif_seq_show, }; static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos) { struct net *net = seq_file_net(seq); struct mr_table *mrt; mrt = ipmr_get_table(net, RT_TABLE_DEFAULT); if (!mrt) return ERR_PTR(-ENOENT); return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock); } static int ipmr_mfc_seq_show(struct seq_file *seq, void *v) { int n; if (v == SEQ_START_TOKEN) { seq_puts(seq, "Group Origin Iif Pkts Bytes Wrong Oifs\n"); } else { const struct mfc_cache *mfc = v; const struct mr_mfc_iter *it = seq->private; const struct mr_table *mrt = it->mrt; seq_printf(seq, "%08X %08X %-3hd", (__force u32) mfc->mfc_mcastgrp, (__force u32) mfc->mfc_origin, mfc->_c.mfc_parent); if (it->cache != &mrt->mfc_unres_queue) { seq_printf(seq, " %8lu %8lu %8lu", mfc->_c.mfc_un.res.pkt, mfc->_c.mfc_un.res.bytes, mfc->_c.mfc_un.res.wrong_if); for (n = mfc->_c.mfc_un.res.minvif; n < mfc->_c.mfc_un.res.maxvif; n++) { if (VIF_EXISTS(mrt, n) && mfc->_c.mfc_un.res.ttls[n] < 255) seq_printf(seq, " %2d:%-3d", n, mfc->_c.mfc_un.res.ttls[n]); } } else { /* unresolved mfc_caches don't contain * pkt, bytes and wrong_if values */ seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul); } seq_putc(seq, '\n'); } return 0; } static const struct seq_operations ipmr_mfc_seq_ops = { .start = ipmr_mfc_seq_start, .next = mr_mfc_seq_next, .stop = mr_mfc_seq_stop, .show = ipmr_mfc_seq_show, }; #endif #ifdef CONFIG_IP_PIMSM_V2 static const struct net_protocol pim_protocol = { .handler = pim_rcv, }; #endif static unsigned int ipmr_seq_read(struct net *net) { ASSERT_RTNL(); return net->ipv4.ipmr_seq + ipmr_rules_seq_read(net); } static int ipmr_dump(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { return mr_dump(net, nb, RTNL_FAMILY_IPMR, ipmr_rules_dump, ipmr_mr_table_iter, extack); } static const struct fib_notifier_ops ipmr_notifier_ops_template = { .family = RTNL_FAMILY_IPMR, .fib_seq_read = ipmr_seq_read, .fib_dump = ipmr_dump, .owner = THIS_MODULE, }; static int __net_init ipmr_notifier_init(struct net *net) { struct fib_notifier_ops *ops; net->ipv4.ipmr_seq = 0; ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net); if (IS_ERR(ops)) return PTR_ERR(ops); net->ipv4.ipmr_notifier_ops = ops; return 0; } static void __net_exit ipmr_notifier_exit(struct net *net) { fib_notifier_ops_unregister(net->ipv4.ipmr_notifier_ops); net->ipv4.ipmr_notifier_ops = NULL; } /* Setup for IP multicast routing */ static int __net_init ipmr_net_init(struct net *net) { int err; err = ipmr_notifier_init(net); if (err) goto ipmr_notifier_fail; err = ipmr_rules_init(net); if (err < 0) goto ipmr_rules_fail; #ifdef CONFIG_PROC_FS err = -ENOMEM; if (!proc_create_net("ip_mr_vif", 0, net->proc_net, &ipmr_vif_seq_ops, sizeof(struct mr_vif_iter))) goto proc_vif_fail; if (!proc_create_net("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops, sizeof(struct mr_mfc_iter))) goto proc_cache_fail; #endif return 0; #ifdef CONFIG_PROC_FS proc_cache_fail: remove_proc_entry("ip_mr_vif", net->proc_net); proc_vif_fail: rtnl_lock(); ipmr_rules_exit(net); rtnl_unlock(); #endif ipmr_rules_fail: ipmr_notifier_exit(net); ipmr_notifier_fail: return err; } static void __net_exit ipmr_net_exit(struct net *net) { #ifdef CONFIG_PROC_FS remove_proc_entry("ip_mr_cache", net->proc_net); remove_proc_entry("ip_mr_vif", net->proc_net); #endif ipmr_notifier_exit(net); } static void __net_exit ipmr_net_exit_batch(struct list_head *net_list) { struct net *net; rtnl_lock(); list_for_each_entry(net, net_list, exit_list) ipmr_rules_exit(net); rtnl_unlock(); } static struct pernet_operations ipmr_net_ops = { .init = ipmr_net_init, .exit = ipmr_net_exit, .exit_batch = ipmr_net_exit_batch, }; int __init ip_mr_init(void) { int err; mrt_cachep = kmem_cache_create("ip_mrt_cache", sizeof(struct mfc_cache), 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL); err = register_pernet_subsys(&ipmr_net_ops); if (err) goto reg_pernet_fail; err = register_netdevice_notifier(&ip_mr_notifier); if (err) goto reg_notif_fail; #ifdef CONFIG_IP_PIMSM_V2 if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) { pr_err("%s: can't add PIM protocol\n", __func__); err = -EAGAIN; goto add_proto_fail; } #endif rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE, ipmr_rtm_getroute, ipmr_rtm_dumproute, 0); rtnl_register(RTNL_FAMILY_IPMR, RTM_NEWROUTE, ipmr_rtm_route, NULL, 0); rtnl_register(RTNL_FAMILY_IPMR, RTM_DELROUTE, ipmr_rtm_route, NULL, 0); rtnl_register(RTNL_FAMILY_IPMR, RTM_GETLINK, NULL, ipmr_rtm_dumplink, 0); return 0; #ifdef CONFIG_IP_PIMSM_V2 add_proto_fail: unregister_netdevice_notifier(&ip_mr_notifier); #endif reg_notif_fail: unregister_pernet_subsys(&ipmr_net_ops); reg_pernet_fail: kmem_cache_destroy(mrt_cachep); return err; }
linux-master
net/ipv4/ipmr.c
// SPDX-License-Identifier: GPL-2.0-only /* * H-TCP congestion control. The algorithm is detailed in: * R.N.Shorten, D.J.Leith: * "H-TCP: TCP for high-speed and long-distance networks" * Proc. PFLDnet, Argonne, 2004. * https://www.hamilton.ie/net/htcp3.pdf */ #include <linux/mm.h> #include <linux/module.h> #include <net/tcp.h> #define ALPHA_BASE (1<<7) /* 1.0 with shift << 7 */ #define BETA_MIN (1<<6) /* 0.5 with shift << 7 */ #define BETA_MAX 102 /* 0.8 with shift << 7 */ static int use_rtt_scaling __read_mostly = 1; module_param(use_rtt_scaling, int, 0644); MODULE_PARM_DESC(use_rtt_scaling, "turn on/off RTT scaling"); static int use_bandwidth_switch __read_mostly = 1; module_param(use_bandwidth_switch, int, 0644); MODULE_PARM_DESC(use_bandwidth_switch, "turn on/off bandwidth switcher"); struct htcp { u32 alpha; /* Fixed point arith, << 7 */ u8 beta; /* Fixed point arith, << 7 */ u8 modeswitch; /* Delay modeswitch until we had at least one congestion event */ u16 pkts_acked; u32 packetcount; u32 minRTT; u32 maxRTT; u32 last_cong; /* Time since last congestion event end */ u32 undo_last_cong; u32 undo_maxRTT; u32 undo_old_maxB; /* Bandwidth estimation */ u32 minB; u32 maxB; u32 old_maxB; u32 Bi; u32 lasttime; }; static inline u32 htcp_cong_time(const struct htcp *ca) { return jiffies - ca->last_cong; } static inline u32 htcp_ccount(const struct htcp *ca) { return htcp_cong_time(ca) / ca->minRTT; } static inline void htcp_reset(struct htcp *ca) { ca->undo_last_cong = ca->last_cong; ca->undo_maxRTT = ca->maxRTT; ca->undo_old_maxB = ca->old_maxB; ca->last_cong = jiffies; } static u32 htcp_cwnd_undo(struct sock *sk) { struct htcp *ca = inet_csk_ca(sk); if (ca->undo_last_cong) { ca->last_cong = ca->undo_last_cong; ca->maxRTT = ca->undo_maxRTT; ca->old_maxB = ca->undo_old_maxB; ca->undo_last_cong = 0; } return tcp_reno_undo_cwnd(sk); } static inline void measure_rtt(struct sock *sk, u32 srtt) { const struct inet_connection_sock *icsk = inet_csk(sk); struct htcp *ca = inet_csk_ca(sk); /* keep track of minimum RTT seen so far, minRTT is zero at first */ if (ca->minRTT > srtt || !ca->minRTT) ca->minRTT = srtt; /* max RTT */ if (icsk->icsk_ca_state == TCP_CA_Open) { if (ca->maxRTT < ca->minRTT) ca->maxRTT = ca->minRTT; if (ca->maxRTT < srtt && srtt <= ca->maxRTT + msecs_to_jiffies(20)) ca->maxRTT = srtt; } } static void measure_achieved_throughput(struct sock *sk, const struct ack_sample *sample) { const struct inet_connection_sock *icsk = inet_csk(sk); const struct tcp_sock *tp = tcp_sk(sk); struct htcp *ca = inet_csk_ca(sk); u32 now = tcp_jiffies32; if (icsk->icsk_ca_state == TCP_CA_Open) ca->pkts_acked = sample->pkts_acked; if (sample->rtt_us > 0) measure_rtt(sk, usecs_to_jiffies(sample->rtt_us)); if (!use_bandwidth_switch) return; /* achieved throughput calculations */ if (!((1 << icsk->icsk_ca_state) & (TCPF_CA_Open | TCPF_CA_Disorder))) { ca->packetcount = 0; ca->lasttime = now; return; } ca->packetcount += sample->pkts_acked; if (ca->packetcount >= tcp_snd_cwnd(tp) - (ca->alpha >> 7 ? : 1) && now - ca->lasttime >= ca->minRTT && ca->minRTT > 0) { __u32 cur_Bi = ca->packetcount * HZ / (now - ca->lasttime); if (htcp_ccount(ca) <= 3) { /* just after backoff */ ca->minB = ca->maxB = ca->Bi = cur_Bi; } else { ca->Bi = (3 * ca->Bi + cur_Bi) / 4; if (ca->Bi > ca->maxB) ca->maxB = ca->Bi; if (ca->minB > ca->maxB) ca->minB = ca->maxB; } ca->packetcount = 0; ca->lasttime = now; } } static inline void htcp_beta_update(struct htcp *ca, u32 minRTT, u32 maxRTT) { if (use_bandwidth_switch) { u32 maxB = ca->maxB; u32 old_maxB = ca->old_maxB; ca->old_maxB = ca->maxB; if (!between(5 * maxB, 4 * old_maxB, 6 * old_maxB)) { ca->beta = BETA_MIN; ca->modeswitch = 0; return; } } if (ca->modeswitch && minRTT > msecs_to_jiffies(10) && maxRTT) { ca->beta = (minRTT << 7) / maxRTT; if (ca->beta < BETA_MIN) ca->beta = BETA_MIN; else if (ca->beta > BETA_MAX) ca->beta = BETA_MAX; } else { ca->beta = BETA_MIN; ca->modeswitch = 1; } } static inline void htcp_alpha_update(struct htcp *ca) { u32 minRTT = ca->minRTT; u32 factor = 1; u32 diff = htcp_cong_time(ca); if (diff > HZ) { diff -= HZ; factor = 1 + (10 * diff + ((diff / 2) * (diff / 2) / HZ)) / HZ; } if (use_rtt_scaling && minRTT) { u32 scale = (HZ << 3) / (10 * minRTT); /* clamping ratio to interval [0.5,10]<<3 */ scale = min(max(scale, 1U << 2), 10U << 3); factor = (factor << 3) / scale; if (!factor) factor = 1; } ca->alpha = 2 * factor * ((1 << 7) - ca->beta); if (!ca->alpha) ca->alpha = ALPHA_BASE; } /* * After we have the rtt data to calculate beta, we'd still prefer to wait one * rtt before we adjust our beta to ensure we are working from a consistent * data. * * This function should be called when we hit a congestion event since only at * that point do we really have a real sense of maxRTT (the queues en route * were getting just too full now). */ static void htcp_param_update(struct sock *sk) { struct htcp *ca = inet_csk_ca(sk); u32 minRTT = ca->minRTT; u32 maxRTT = ca->maxRTT; htcp_beta_update(ca, minRTT, maxRTT); htcp_alpha_update(ca); /* add slowly fading memory for maxRTT to accommodate routing changes */ if (minRTT > 0 && maxRTT > minRTT) ca->maxRTT = minRTT + ((maxRTT - minRTT) * 95) / 100; } static u32 htcp_recalc_ssthresh(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); const struct htcp *ca = inet_csk_ca(sk); htcp_param_update(sk); return max((tcp_snd_cwnd(tp) * ca->beta) >> 7, 2U); } static void htcp_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct htcp *ca = inet_csk_ca(sk); if (!tcp_is_cwnd_limited(sk)) return; if (tcp_in_slow_start(tp)) tcp_slow_start(tp, acked); else { /* In dangerous area, increase slowly. * In theory this is tp->snd_cwnd += alpha / tp->snd_cwnd */ if ((tp->snd_cwnd_cnt * ca->alpha)>>7 >= tcp_snd_cwnd(tp)) { if (tcp_snd_cwnd(tp) < tp->snd_cwnd_clamp) tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) + 1); tp->snd_cwnd_cnt = 0; htcp_alpha_update(ca); } else tp->snd_cwnd_cnt += ca->pkts_acked; ca->pkts_acked = 1; } } static void htcp_init(struct sock *sk) { struct htcp *ca = inet_csk_ca(sk); memset(ca, 0, sizeof(struct htcp)); ca->alpha = ALPHA_BASE; ca->beta = BETA_MIN; ca->pkts_acked = 1; ca->last_cong = jiffies; } static void htcp_state(struct sock *sk, u8 new_state) { switch (new_state) { case TCP_CA_Open: { struct htcp *ca = inet_csk_ca(sk); if (ca->undo_last_cong) { ca->last_cong = jiffies; ca->undo_last_cong = 0; } } break; case TCP_CA_CWR: case TCP_CA_Recovery: case TCP_CA_Loss: htcp_reset(inet_csk_ca(sk)); break; } } static struct tcp_congestion_ops htcp __read_mostly = { .init = htcp_init, .ssthresh = htcp_recalc_ssthresh, .cong_avoid = htcp_cong_avoid, .set_state = htcp_state, .undo_cwnd = htcp_cwnd_undo, .pkts_acked = measure_achieved_throughput, .owner = THIS_MODULE, .name = "htcp", }; static int __init htcp_register(void) { BUILD_BUG_ON(sizeof(struct htcp) > ICSK_CA_PRIV_SIZE); BUILD_BUG_ON(BETA_MIN >= BETA_MAX); return tcp_register_congestion_control(&htcp); } static void __exit htcp_unregister(void) { tcp_unregister_congestion_control(&htcp); } module_init(htcp_register); module_exit(htcp_unregister); MODULE_AUTHOR("Baruch Even"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("H-TCP");
linux-master
net/ipv4/tcp_htcp.c
// SPDX-License-Identifier: GPL-2.0 #include <linux/kernel.h> #include <linux/tcp.h> #include <linux/rcupdate.h> #include <net/tcp.h> void tcp_fastopen_init_key_once(struct net *net) { u8 key[TCP_FASTOPEN_KEY_LENGTH]; struct tcp_fastopen_context *ctxt; rcu_read_lock(); ctxt = rcu_dereference(net->ipv4.tcp_fastopen_ctx); if (ctxt) { rcu_read_unlock(); return; } rcu_read_unlock(); /* tcp_fastopen_reset_cipher publishes the new context * atomically, so we allow this race happening here. * * All call sites of tcp_fastopen_cookie_gen also check * for a valid cookie, so this is an acceptable risk. */ get_random_bytes(key, sizeof(key)); tcp_fastopen_reset_cipher(net, NULL, key, NULL); } static void tcp_fastopen_ctx_free(struct rcu_head *head) { struct tcp_fastopen_context *ctx = container_of(head, struct tcp_fastopen_context, rcu); kfree_sensitive(ctx); } void tcp_fastopen_destroy_cipher(struct sock *sk) { struct tcp_fastopen_context *ctx; ctx = rcu_dereference_protected( inet_csk(sk)->icsk_accept_queue.fastopenq.ctx, 1); if (ctx) call_rcu(&ctx->rcu, tcp_fastopen_ctx_free); } void tcp_fastopen_ctx_destroy(struct net *net) { struct tcp_fastopen_context *ctxt; ctxt = xchg((__force struct tcp_fastopen_context **)&net->ipv4.tcp_fastopen_ctx, NULL); if (ctxt) call_rcu(&ctxt->rcu, tcp_fastopen_ctx_free); } int tcp_fastopen_reset_cipher(struct net *net, struct sock *sk, void *primary_key, void *backup_key) { struct tcp_fastopen_context *ctx, *octx; struct fastopen_queue *q; int err = 0; ctx = kmalloc(sizeof(*ctx), GFP_KERNEL); if (!ctx) { err = -ENOMEM; goto out; } ctx->key[0].key[0] = get_unaligned_le64(primary_key); ctx->key[0].key[1] = get_unaligned_le64(primary_key + 8); if (backup_key) { ctx->key[1].key[0] = get_unaligned_le64(backup_key); ctx->key[1].key[1] = get_unaligned_le64(backup_key + 8); ctx->num = 2; } else { ctx->num = 1; } if (sk) { q = &inet_csk(sk)->icsk_accept_queue.fastopenq; octx = xchg((__force struct tcp_fastopen_context **)&q->ctx, ctx); } else { octx = xchg((__force struct tcp_fastopen_context **)&net->ipv4.tcp_fastopen_ctx, ctx); } if (octx) call_rcu(&octx->rcu, tcp_fastopen_ctx_free); out: return err; } int tcp_fastopen_get_cipher(struct net *net, struct inet_connection_sock *icsk, u64 *key) { struct tcp_fastopen_context *ctx; int n_keys = 0, i; rcu_read_lock(); if (icsk) ctx = rcu_dereference(icsk->icsk_accept_queue.fastopenq.ctx); else ctx = rcu_dereference(net->ipv4.tcp_fastopen_ctx); if (ctx) { n_keys = tcp_fastopen_context_len(ctx); for (i = 0; i < n_keys; i++) { put_unaligned_le64(ctx->key[i].key[0], key + (i * 2)); put_unaligned_le64(ctx->key[i].key[1], key + (i * 2) + 1); } } rcu_read_unlock(); return n_keys; } static bool __tcp_fastopen_cookie_gen_cipher(struct request_sock *req, struct sk_buff *syn, const siphash_key_t *key, struct tcp_fastopen_cookie *foc) { BUILD_BUG_ON(TCP_FASTOPEN_COOKIE_SIZE != sizeof(u64)); if (req->rsk_ops->family == AF_INET) { const struct iphdr *iph = ip_hdr(syn); foc->val[0] = cpu_to_le64(siphash(&iph->saddr, sizeof(iph->saddr) + sizeof(iph->daddr), key)); foc->len = TCP_FASTOPEN_COOKIE_SIZE; return true; } #if IS_ENABLED(CONFIG_IPV6) if (req->rsk_ops->family == AF_INET6) { const struct ipv6hdr *ip6h = ipv6_hdr(syn); foc->val[0] = cpu_to_le64(siphash(&ip6h->saddr, sizeof(ip6h->saddr) + sizeof(ip6h->daddr), key)); foc->len = TCP_FASTOPEN_COOKIE_SIZE; return true; } #endif return false; } /* Generate the fastopen cookie by applying SipHash to both the source and * destination addresses. */ static void tcp_fastopen_cookie_gen(struct sock *sk, struct request_sock *req, struct sk_buff *syn, struct tcp_fastopen_cookie *foc) { struct tcp_fastopen_context *ctx; rcu_read_lock(); ctx = tcp_fastopen_get_ctx(sk); if (ctx) __tcp_fastopen_cookie_gen_cipher(req, syn, &ctx->key[0], foc); rcu_read_unlock(); } /* If an incoming SYN or SYNACK frame contains a payload and/or FIN, * queue this additional data / FIN. */ void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); if (TCP_SKB_CB(skb)->end_seq == tp->rcv_nxt) return; skb = skb_clone(skb, GFP_ATOMIC); if (!skb) return; skb_dst_drop(skb); /* segs_in has been initialized to 1 in tcp_create_openreq_child(). * Hence, reset segs_in to 0 before calling tcp_segs_in() * to avoid double counting. Also, tcp_segs_in() expects * skb->len to include the tcp_hdrlen. Hence, it should * be called before __skb_pull(). */ tp->segs_in = 0; tcp_segs_in(tp, skb); __skb_pull(skb, tcp_hdrlen(skb)); sk_forced_mem_schedule(sk, skb->truesize); skb_set_owner_r(skb, sk); TCP_SKB_CB(skb)->seq++; TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_SYN; tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq; __skb_queue_tail(&sk->sk_receive_queue, skb); tp->syn_data_acked = 1; /* u64_stats_update_begin(&tp->syncp) not needed here, * as we certainly are not changing upper 32bit value (0) */ tp->bytes_received = skb->len; if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) tcp_fin(sk); } /* returns 0 - no key match, 1 for primary, 2 for backup */ static int tcp_fastopen_cookie_gen_check(struct sock *sk, struct request_sock *req, struct sk_buff *syn, struct tcp_fastopen_cookie *orig, struct tcp_fastopen_cookie *valid_foc) { struct tcp_fastopen_cookie search_foc = { .len = -1 }; struct tcp_fastopen_cookie *foc = valid_foc; struct tcp_fastopen_context *ctx; int i, ret = 0; rcu_read_lock(); ctx = tcp_fastopen_get_ctx(sk); if (!ctx) goto out; for (i = 0; i < tcp_fastopen_context_len(ctx); i++) { __tcp_fastopen_cookie_gen_cipher(req, syn, &ctx->key[i], foc); if (tcp_fastopen_cookie_match(foc, orig)) { ret = i + 1; goto out; } foc = &search_foc; } out: rcu_read_unlock(); return ret; } static struct sock *tcp_fastopen_create_child(struct sock *sk, struct sk_buff *skb, struct request_sock *req) { struct tcp_sock *tp; struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; struct sock *child; bool own_req; child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL, NULL, &own_req); if (!child) return NULL; spin_lock(&queue->fastopenq.lock); queue->fastopenq.qlen++; spin_unlock(&queue->fastopenq.lock); /* Initialize the child socket. Have to fix some values to take * into account the child is a Fast Open socket and is created * only out of the bits carried in the SYN packet. */ tp = tcp_sk(child); rcu_assign_pointer(tp->fastopen_rsk, req); tcp_rsk(req)->tfo_listener = true; /* RFC1323: The window in SYN & SYN/ACK segments is never * scaled. So correct it appropriately. */ tp->snd_wnd = ntohs(tcp_hdr(skb)->window); tp->max_window = tp->snd_wnd; /* Activate the retrans timer so that SYNACK can be retransmitted. * The request socket is not added to the ehash * because it's been added to the accept queue directly. */ req->timeout = tcp_timeout_init(child); inet_csk_reset_xmit_timer(child, ICSK_TIME_RETRANS, req->timeout, TCP_RTO_MAX); refcount_set(&req->rsk_refcnt, 2); /* Now finish processing the fastopen child socket. */ tcp_init_transfer(child, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB, skb); tp->rcv_nxt = TCP_SKB_CB(skb)->seq + 1; tcp_fastopen_add_skb(child, skb); tcp_rsk(req)->rcv_nxt = tp->rcv_nxt; tp->rcv_wup = tp->rcv_nxt; /* tcp_conn_request() is sending the SYNACK, * and queues the child into listener accept queue. */ return child; } static bool tcp_fastopen_queue_check(struct sock *sk) { struct fastopen_queue *fastopenq; int max_qlen; /* Make sure the listener has enabled fastopen, and we don't * exceed the max # of pending TFO requests allowed before trying * to validating the cookie in order to avoid burning CPU cycles * unnecessarily. * * XXX (TFO) - The implication of checking the max_qlen before * processing a cookie request is that clients can't differentiate * between qlen overflow causing Fast Open to be disabled * temporarily vs a server not supporting Fast Open at all. */ fastopenq = &inet_csk(sk)->icsk_accept_queue.fastopenq; max_qlen = READ_ONCE(fastopenq->max_qlen); if (max_qlen == 0) return false; if (fastopenq->qlen >= max_qlen) { struct request_sock *req1; spin_lock(&fastopenq->lock); req1 = fastopenq->rskq_rst_head; if (!req1 || time_after(req1->rsk_timer.expires, jiffies)) { __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENLISTENOVERFLOW); spin_unlock(&fastopenq->lock); return false; } fastopenq->rskq_rst_head = req1->dl_next; fastopenq->qlen--; spin_unlock(&fastopenq->lock); reqsk_put(req1); } return true; } static bool tcp_fastopen_no_cookie(const struct sock *sk, const struct dst_entry *dst, int flag) { return (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen) & flag) || tcp_sk(sk)->fastopen_no_cookie || (dst && dst_metric(dst, RTAX_FASTOPEN_NO_COOKIE)); } /* Returns true if we should perform Fast Open on the SYN. The cookie (foc) * may be updated and return the client in the SYN-ACK later. E.g., Fast Open * cookie request (foc->len == 0). */ struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct tcp_fastopen_cookie *foc, const struct dst_entry *dst) { bool syn_data = TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq + 1; int tcp_fastopen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen); struct tcp_fastopen_cookie valid_foc = { .len = -1 }; struct sock *child; int ret = 0; if (foc->len == 0) /* Client requests a cookie */ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENCOOKIEREQD); if (!((tcp_fastopen & TFO_SERVER_ENABLE) && (syn_data || foc->len >= 0) && tcp_fastopen_queue_check(sk))) { foc->len = -1; return NULL; } if (tcp_fastopen_no_cookie(sk, dst, TFO_SERVER_COOKIE_NOT_REQD)) goto fastopen; if (foc->len == 0) { /* Client requests a cookie. */ tcp_fastopen_cookie_gen(sk, req, skb, &valid_foc); } else if (foc->len > 0) { ret = tcp_fastopen_cookie_gen_check(sk, req, skb, foc, &valid_foc); if (!ret) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVEFAIL); } else { /* Cookie is valid. Create a (full) child socket to * accept the data in SYN before returning a SYN-ACK to * ack the data. If we fail to create the socket, fall * back and ack the ISN only but includes the same * cookie. * * Note: Data-less SYN with valid cookie is allowed to * send data in SYN_RECV state. */ fastopen: child = tcp_fastopen_create_child(sk, skb, req); if (child) { if (ret == 2) { valid_foc.exp = foc->exp; *foc = valid_foc; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVEALTKEY); } else { foc->len = -1; } NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVE); return child; } NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVEFAIL); } } valid_foc.exp = foc->exp; *foc = valid_foc; return NULL; } bool tcp_fastopen_cookie_check(struct sock *sk, u16 *mss, struct tcp_fastopen_cookie *cookie) { const struct dst_entry *dst; tcp_fastopen_cache_get(sk, mss, cookie); /* Firewall blackhole issue check */ if (tcp_fastopen_active_should_disable(sk)) { cookie->len = -1; return false; } dst = __sk_dst_get(sk); if (tcp_fastopen_no_cookie(sk, dst, TFO_CLIENT_NO_COOKIE)) { cookie->len = -1; return true; } if (cookie->len > 0) return true; tcp_sk(sk)->fastopen_client_fail = TFO_COOKIE_UNAVAILABLE; return false; } /* This function checks if we want to defer sending SYN until the first * write(). We defer under the following conditions: * 1. fastopen_connect sockopt is set * 2. we have a valid cookie * Return value: return true if we want to defer until application writes data * return false if we want to send out SYN immediately */ bool tcp_fastopen_defer_connect(struct sock *sk, int *err) { struct tcp_fastopen_cookie cookie = { .len = 0 }; struct tcp_sock *tp = tcp_sk(sk); u16 mss; if (tp->fastopen_connect && !tp->fastopen_req) { if (tcp_fastopen_cookie_check(sk, &mss, &cookie)) { inet_set_bit(DEFER_CONNECT, sk); return true; } /* Alloc fastopen_req in order for FO option to be included * in SYN */ tp->fastopen_req = kzalloc(sizeof(*tp->fastopen_req), sk->sk_allocation); if (tp->fastopen_req) tp->fastopen_req->cookie = cookie; else *err = -ENOBUFS; } return false; } EXPORT_SYMBOL(tcp_fastopen_defer_connect); /* * The following code block is to deal with middle box issues with TFO: * Middlebox firewall issues can potentially cause server's data being * blackholed after a successful 3WHS using TFO. * The proposed solution is to disable active TFO globally under the * following circumstances: * 1. client side TFO socket receives out of order FIN * 2. client side TFO socket receives out of order RST * 3. client side TFO socket has timed out three times consecutively during * or after handshake * We disable active side TFO globally for 1hr at first. Then if it * happens again, we disable it for 2h, then 4h, 8h, ... * And we reset the timeout back to 1hr when we see a successful active * TFO connection with data exchanges. */ /* Disable active TFO and record current jiffies and * tfo_active_disable_times */ void tcp_fastopen_active_disable(struct sock *sk) { struct net *net = sock_net(sk); if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen_blackhole_timeout)) return; /* Paired with READ_ONCE() in tcp_fastopen_active_should_disable() */ WRITE_ONCE(net->ipv4.tfo_active_disable_stamp, jiffies); /* Paired with smp_rmb() in tcp_fastopen_active_should_disable(). * We want net->ipv4.tfo_active_disable_stamp to be updated first. */ smp_mb__before_atomic(); atomic_inc(&net->ipv4.tfo_active_disable_times); NET_INC_STATS(net, LINUX_MIB_TCPFASTOPENBLACKHOLE); } /* Calculate timeout for tfo active disable * Return true if we are still in the active TFO disable period * Return false if timeout already expired and we should use active TFO */ bool tcp_fastopen_active_should_disable(struct sock *sk) { unsigned int tfo_bh_timeout = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen_blackhole_timeout); unsigned long timeout; int tfo_da_times; int multiplier; if (!tfo_bh_timeout) return false; tfo_da_times = atomic_read(&sock_net(sk)->ipv4.tfo_active_disable_times); if (!tfo_da_times) return false; /* Paired with smp_mb__before_atomic() in tcp_fastopen_active_disable() */ smp_rmb(); /* Limit timeout to max: 2^6 * initial timeout */ multiplier = 1 << min(tfo_da_times - 1, 6); /* Paired with the WRITE_ONCE() in tcp_fastopen_active_disable(). */ timeout = READ_ONCE(sock_net(sk)->ipv4.tfo_active_disable_stamp) + multiplier * tfo_bh_timeout * HZ; if (time_before(jiffies, timeout)) return true; /* Mark check bit so we can check for successful active TFO * condition and reset tfo_active_disable_times */ tcp_sk(sk)->syn_fastopen_ch = 1; return false; } /* Disable active TFO if FIN is the only packet in the ofo queue * and no data is received. * Also check if we can reset tfo_active_disable_times if data is * received successfully on a marked active TFO sockets opened on * a non-loopback interface */ void tcp_fastopen_active_disable_ofo_check(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct dst_entry *dst; struct sk_buff *skb; if (!tp->syn_fastopen) return; if (!tp->data_segs_in) { skb = skb_rb_first(&tp->out_of_order_queue); if (skb && !skb_rb_next(skb)) { if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) { tcp_fastopen_active_disable(sk); return; } } } else if (tp->syn_fastopen_ch && atomic_read(&sock_net(sk)->ipv4.tfo_active_disable_times)) { dst = sk_dst_get(sk); if (!(dst && dst->dev && (dst->dev->flags & IFF_LOOPBACK))) atomic_set(&sock_net(sk)->ipv4.tfo_active_disable_times, 0); dst_release(dst); } } void tcp_fastopen_active_detect_blackhole(struct sock *sk, bool expired) { u32 timeouts = inet_csk(sk)->icsk_retransmits; struct tcp_sock *tp = tcp_sk(sk); /* Broken middle-boxes may black-hole Fast Open connection during or * even after the handshake. Be extremely conservative and pause * Fast Open globally after hitting the third consecutive timeout or * exceeding the configured timeout limit. */ if ((tp->syn_fastopen || tp->syn_data || tp->syn_data_acked) && (timeouts == 2 || (timeouts < 2 && expired))) { tcp_fastopen_active_disable(sk); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENACTIVEFAIL); } }
linux-master
net/ipv4/tcp_fastopen.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * UDPLITE An implementation of the UDP-Lite protocol (RFC 3828). * * Authors: Gerrit Renker <[email protected]> * * Changes: * Fixes: */ #define pr_fmt(fmt) "UDPLite: " fmt #include <linux/export.h> #include <linux/proc_fs.h> #include "udp_impl.h" struct udp_table udplite_table __read_mostly; EXPORT_SYMBOL(udplite_table); /* Designate sk as UDP-Lite socket */ static int udplite_sk_init(struct sock *sk) { udp_init_sock(sk); udp_sk(sk)->pcflag = UDPLITE_BIT; pr_warn_once("UDP-Lite is deprecated and scheduled to be removed in 2025, " "please contact the netdev mailing list\n"); return 0; } static int udplite_rcv(struct sk_buff *skb) { return __udp4_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE); } static int udplite_err(struct sk_buff *skb, u32 info) { return __udp4_lib_err(skb, info, &udplite_table); } static const struct net_protocol udplite_protocol = { .handler = udplite_rcv, .err_handler = udplite_err, .no_policy = 1, }; struct proto udplite_prot = { .name = "UDP-Lite", .owner = THIS_MODULE, .close = udp_lib_close, .connect = ip4_datagram_connect, .disconnect = udp_disconnect, .ioctl = udp_ioctl, .init = udplite_sk_init, .destroy = udp_destroy_sock, .setsockopt = udp_setsockopt, .getsockopt = udp_getsockopt, .sendmsg = udp_sendmsg, .recvmsg = udp_recvmsg, .hash = udp_lib_hash, .unhash = udp_lib_unhash, .rehash = udp_v4_rehash, .get_port = udp_v4_get_port, .memory_allocated = &udp_memory_allocated, .per_cpu_fw_alloc = &udp_memory_per_cpu_fw_alloc, .sysctl_mem = sysctl_udp_mem, .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min), .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min), .obj_size = sizeof(struct udp_sock), .h.udp_table = &udplite_table, }; EXPORT_SYMBOL(udplite_prot); static struct inet_protosw udplite4_protosw = { .type = SOCK_DGRAM, .protocol = IPPROTO_UDPLITE, .prot = &udplite_prot, .ops = &inet_dgram_ops, .flags = INET_PROTOSW_PERMANENT, }; #ifdef CONFIG_PROC_FS static struct udp_seq_afinfo udplite4_seq_afinfo = { .family = AF_INET, .udp_table = &udplite_table, }; static int __net_init udplite4_proc_init_net(struct net *net) { if (!proc_create_net_data("udplite", 0444, net->proc_net, &udp_seq_ops, sizeof(struct udp_iter_state), &udplite4_seq_afinfo)) return -ENOMEM; return 0; } static void __net_exit udplite4_proc_exit_net(struct net *net) { remove_proc_entry("udplite", net->proc_net); } static struct pernet_operations udplite4_net_ops = { .init = udplite4_proc_init_net, .exit = udplite4_proc_exit_net, }; static __init int udplite4_proc_init(void) { return register_pernet_subsys(&udplite4_net_ops); } #else static inline int udplite4_proc_init(void) { return 0; } #endif void __init udplite4_register(void) { udp_table_init(&udplite_table, "UDP-Lite"); if (proto_register(&udplite_prot, 1)) goto out_register_err; if (inet_add_protocol(&udplite_protocol, IPPROTO_UDPLITE) < 0) goto out_unregister_proto; inet_register_protosw(&udplite4_protosw); if (udplite4_proc_init()) pr_err("%s: Cannot register /proc!\n", __func__); return; out_unregister_proto: proto_unregister(&udplite_prot); out_register_err: pr_crit("%s: Cannot add UDP-Lite protocol\n", __func__); }
linux-master
net/ipv4/udplite.c
// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) /* Do not edit directly, auto-generated from: */ /* Documentation/netlink/specs/fou.yaml */ /* YNL-GEN kernel source */ #include <net/netlink.h> #include <net/genetlink.h> #include "fou_nl.h" #include <uapi/linux/fou.h> /* Global operation policy for fou */ const struct nla_policy fou_nl_policy[FOU_ATTR_IFINDEX + 1] = { [FOU_ATTR_PORT] = { .type = NLA_U16, }, [FOU_ATTR_AF] = { .type = NLA_U8, }, [FOU_ATTR_IPPROTO] = { .type = NLA_U8, }, [FOU_ATTR_TYPE] = { .type = NLA_U8, }, [FOU_ATTR_REMCSUM_NOPARTIAL] = { .type = NLA_FLAG, }, [FOU_ATTR_LOCAL_V4] = { .type = NLA_U32, }, [FOU_ATTR_LOCAL_V6] = { .len = 16, }, [FOU_ATTR_PEER_V4] = { .type = NLA_U32, }, [FOU_ATTR_PEER_V6] = { .len = 16, }, [FOU_ATTR_PEER_PORT] = { .type = NLA_U16, }, [FOU_ATTR_IFINDEX] = { .type = NLA_S32, }, }; /* Ops table for fou */ const struct genl_small_ops fou_nl_ops[3] = { { .cmd = FOU_CMD_ADD, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = fou_nl_add_doit, .flags = GENL_ADMIN_PERM, }, { .cmd = FOU_CMD_DEL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = fou_nl_del_doit, .flags = GENL_ADMIN_PERM, }, { .cmd = FOU_CMD_GET, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = fou_nl_get_doit, .dumpit = fou_nl_get_dumpit, }, };
linux-master
net/ipv4/fou_nl.c
// SPDX-License-Identifier: GPL-2.0-only #include <linux/module.h> #include <linux/errno.h> #include <linux/socket.h> #include <linux/skbuff.h> #include <linux/ip.h> #include <linux/icmp.h> #include <linux/udp.h> #include <linux/types.h> #include <linux/kernel.h> #include <net/genetlink.h> #include <net/gro.h> #include <net/gue.h> #include <net/fou.h> #include <net/ip.h> #include <net/protocol.h> #include <net/udp.h> #include <net/udp_tunnel.h> #include <uapi/linux/fou.h> #include <uapi/linux/genetlink.h> #include "fou_nl.h" struct fou { struct socket *sock; u8 protocol; u8 flags; __be16 port; u8 family; u16 type; struct list_head list; struct rcu_head rcu; }; #define FOU_F_REMCSUM_NOPARTIAL BIT(0) struct fou_cfg { u16 type; u8 protocol; u8 flags; struct udp_port_cfg udp_config; }; static unsigned int fou_net_id; struct fou_net { struct list_head fou_list; struct mutex fou_lock; }; static inline struct fou *fou_from_sock(struct sock *sk) { return sk->sk_user_data; } static int fou_recv_pull(struct sk_buff *skb, struct fou *fou, size_t len) { /* Remove 'len' bytes from the packet (UDP header and * FOU header if present). */ if (fou->family == AF_INET) ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len); else ipv6_hdr(skb)->payload_len = htons(ntohs(ipv6_hdr(skb)->payload_len) - len); __skb_pull(skb, len); skb_postpull_rcsum(skb, udp_hdr(skb), len); skb_reset_transport_header(skb); return iptunnel_pull_offloads(skb); } static int fou_udp_recv(struct sock *sk, struct sk_buff *skb) { struct fou *fou = fou_from_sock(sk); if (!fou) return 1; if (fou_recv_pull(skb, fou, sizeof(struct udphdr))) goto drop; return -fou->protocol; drop: kfree_skb(skb); return 0; } static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr, void *data, size_t hdrlen, u8 ipproto, bool nopartial) { __be16 *pd = data; size_t start = ntohs(pd[0]); size_t offset = ntohs(pd[1]); size_t plen = sizeof(struct udphdr) + hdrlen + max_t(size_t, offset + sizeof(u16), start); if (skb->remcsum_offload) return guehdr; if (!pskb_may_pull(skb, plen)) return NULL; guehdr = (struct guehdr *)&udp_hdr(skb)[1]; skb_remcsum_process(skb, (void *)guehdr + hdrlen, start, offset, nopartial); return guehdr; } static int gue_control_message(struct sk_buff *skb, struct guehdr *guehdr) { /* No support yet */ kfree_skb(skb); return 0; } static int gue_udp_recv(struct sock *sk, struct sk_buff *skb) { struct fou *fou = fou_from_sock(sk); size_t len, optlen, hdrlen; struct guehdr *guehdr; void *data; u16 doffset = 0; u8 proto_ctype; if (!fou) return 1; len = sizeof(struct udphdr) + sizeof(struct guehdr); if (!pskb_may_pull(skb, len)) goto drop; guehdr = (struct guehdr *)&udp_hdr(skb)[1]; switch (guehdr->version) { case 0: /* Full GUE header present */ break; case 1: { /* Direct encapsulation of IPv4 or IPv6 */ int prot; switch (((struct iphdr *)guehdr)->version) { case 4: prot = IPPROTO_IPIP; break; case 6: prot = IPPROTO_IPV6; break; default: goto drop; } if (fou_recv_pull(skb, fou, sizeof(struct udphdr))) goto drop; return -prot; } default: /* Undefined version */ goto drop; } optlen = guehdr->hlen << 2; len += optlen; if (!pskb_may_pull(skb, len)) goto drop; /* guehdr may change after pull */ guehdr = (struct guehdr *)&udp_hdr(skb)[1]; if (validate_gue_flags(guehdr, optlen)) goto drop; hdrlen = sizeof(struct guehdr) + optlen; if (fou->family == AF_INET) ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len); else ipv6_hdr(skb)->payload_len = htons(ntohs(ipv6_hdr(skb)->payload_len) - len); /* Pull csum through the guehdr now . This can be used if * there is a remote checksum offload. */ skb_postpull_rcsum(skb, udp_hdr(skb), len); data = &guehdr[1]; if (guehdr->flags & GUE_FLAG_PRIV) { __be32 flags = *(__be32 *)(data + doffset); doffset += GUE_LEN_PRIV; if (flags & GUE_PFLAG_REMCSUM) { guehdr = gue_remcsum(skb, guehdr, data + doffset, hdrlen, guehdr->proto_ctype, !!(fou->flags & FOU_F_REMCSUM_NOPARTIAL)); if (!guehdr) goto drop; data = &guehdr[1]; doffset += GUE_PLEN_REMCSUM; } } if (unlikely(guehdr->control)) return gue_control_message(skb, guehdr); proto_ctype = guehdr->proto_ctype; __skb_pull(skb, sizeof(struct udphdr) + hdrlen); skb_reset_transport_header(skb); if (iptunnel_pull_offloads(skb)) goto drop; return -proto_ctype; drop: kfree_skb(skb); return 0; } static struct sk_buff *fou_gro_receive(struct sock *sk, struct list_head *head, struct sk_buff *skb) { const struct net_offload __rcu **offloads; u8 proto = fou_from_sock(sk)->protocol; const struct net_offload *ops; struct sk_buff *pp = NULL; /* We can clear the encap_mark for FOU as we are essentially doing * one of two possible things. We are either adding an L4 tunnel * header to the outer L3 tunnel header, or we are simply * treating the GRE tunnel header as though it is a UDP protocol * specific header such as VXLAN or GENEVE. */ NAPI_GRO_CB(skb)->encap_mark = 0; /* Flag this frame as already having an outer encap header */ NAPI_GRO_CB(skb)->is_fou = 1; offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[proto]); if (!ops || !ops->callbacks.gro_receive) goto out; pp = call_gro_receive(ops->callbacks.gro_receive, head, skb); out: return pp; } static int fou_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff) { const struct net_offload __rcu **offloads; u8 proto = fou_from_sock(sk)->protocol; const struct net_offload *ops; int err = -ENOSYS; offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[proto]); if (WARN_ON(!ops || !ops->callbacks.gro_complete)) goto out; err = ops->callbacks.gro_complete(skb, nhoff); skb_set_inner_mac_header(skb, nhoff); out: return err; } static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off, struct guehdr *guehdr, void *data, size_t hdrlen, struct gro_remcsum *grc, bool nopartial) { __be16 *pd = data; size_t start = ntohs(pd[0]); size_t offset = ntohs(pd[1]); if (skb->remcsum_offload) return guehdr; if (!NAPI_GRO_CB(skb)->csum_valid) return NULL; guehdr = skb_gro_remcsum_process(skb, (void *)guehdr, off, hdrlen, start, offset, grc, nopartial); skb->remcsum_offload = 1; return guehdr; } static struct sk_buff *gue_gro_receive(struct sock *sk, struct list_head *head, struct sk_buff *skb) { const struct net_offload __rcu **offloads; const struct net_offload *ops; struct sk_buff *pp = NULL; struct sk_buff *p; struct guehdr *guehdr; size_t len, optlen, hdrlen, off; void *data; u16 doffset = 0; int flush = 1; struct fou *fou = fou_from_sock(sk); struct gro_remcsum grc; u8 proto; skb_gro_remcsum_init(&grc); off = skb_gro_offset(skb); len = off + sizeof(*guehdr); guehdr = skb_gro_header(skb, len, off); if (unlikely(!guehdr)) goto out; switch (guehdr->version) { case 0: break; case 1: switch (((struct iphdr *)guehdr)->version) { case 4: proto = IPPROTO_IPIP; break; case 6: proto = IPPROTO_IPV6; break; default: goto out; } goto next_proto; default: goto out; } optlen = guehdr->hlen << 2; len += optlen; if (skb_gro_header_hard(skb, len)) { guehdr = skb_gro_header_slow(skb, len, off); if (unlikely(!guehdr)) goto out; } if (unlikely(guehdr->control) || guehdr->version != 0 || validate_gue_flags(guehdr, optlen)) goto out; hdrlen = sizeof(*guehdr) + optlen; /* Adjust NAPI_GRO_CB(skb)->csum to account for guehdr, * this is needed if there is a remote checkcsum offload. */ skb_gro_postpull_rcsum(skb, guehdr, hdrlen); data = &guehdr[1]; if (guehdr->flags & GUE_FLAG_PRIV) { __be32 flags = *(__be32 *)(data + doffset); doffset += GUE_LEN_PRIV; if (flags & GUE_PFLAG_REMCSUM) { guehdr = gue_gro_remcsum(skb, off, guehdr, data + doffset, hdrlen, &grc, !!(fou->flags & FOU_F_REMCSUM_NOPARTIAL)); if (!guehdr) goto out; data = &guehdr[1]; doffset += GUE_PLEN_REMCSUM; } } skb_gro_pull(skb, hdrlen); list_for_each_entry(p, head, list) { const struct guehdr *guehdr2; if (!NAPI_GRO_CB(p)->same_flow) continue; guehdr2 = (struct guehdr *)(p->data + off); /* Compare base GUE header to be equal (covers * hlen, version, proto_ctype, and flags. */ if (guehdr->word != guehdr2->word) { NAPI_GRO_CB(p)->same_flow = 0; continue; } /* Compare optional fields are the same. */ if (guehdr->hlen && memcmp(&guehdr[1], &guehdr2[1], guehdr->hlen << 2)) { NAPI_GRO_CB(p)->same_flow = 0; continue; } } proto = guehdr->proto_ctype; next_proto: /* We can clear the encap_mark for GUE as we are essentially doing * one of two possible things. We are either adding an L4 tunnel * header to the outer L3 tunnel header, or we are simply * treating the GRE tunnel header as though it is a UDP protocol * specific header such as VXLAN or GENEVE. */ NAPI_GRO_CB(skb)->encap_mark = 0; /* Flag this frame as already having an outer encap header */ NAPI_GRO_CB(skb)->is_fou = 1; offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[proto]); if (WARN_ON_ONCE(!ops || !ops->callbacks.gro_receive)) goto out; pp = call_gro_receive(ops->callbacks.gro_receive, head, skb); flush = 0; out: skb_gro_flush_final_remcsum(skb, pp, flush, &grc); return pp; } static int gue_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff) { struct guehdr *guehdr = (struct guehdr *)(skb->data + nhoff); const struct net_offload __rcu **offloads; const struct net_offload *ops; unsigned int guehlen = 0; u8 proto; int err = -ENOENT; switch (guehdr->version) { case 0: proto = guehdr->proto_ctype; guehlen = sizeof(*guehdr) + (guehdr->hlen << 2); break; case 1: switch (((struct iphdr *)guehdr)->version) { case 4: proto = IPPROTO_IPIP; break; case 6: proto = IPPROTO_IPV6; break; default: return err; } break; default: return err; } offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[proto]); if (WARN_ON(!ops || !ops->callbacks.gro_complete)) goto out; err = ops->callbacks.gro_complete(skb, nhoff + guehlen); skb_set_inner_mac_header(skb, nhoff + guehlen); out: return err; } static bool fou_cfg_cmp(struct fou *fou, struct fou_cfg *cfg) { struct sock *sk = fou->sock->sk; struct udp_port_cfg *udp_cfg = &cfg->udp_config; if (fou->family != udp_cfg->family || fou->port != udp_cfg->local_udp_port || sk->sk_dport != udp_cfg->peer_udp_port || sk->sk_bound_dev_if != udp_cfg->bind_ifindex) return false; if (fou->family == AF_INET) { if (sk->sk_rcv_saddr != udp_cfg->local_ip.s_addr || sk->sk_daddr != udp_cfg->peer_ip.s_addr) return false; else return true; #if IS_ENABLED(CONFIG_IPV6) } else { if (ipv6_addr_cmp(&sk->sk_v6_rcv_saddr, &udp_cfg->local_ip6) || ipv6_addr_cmp(&sk->sk_v6_daddr, &udp_cfg->peer_ip6)) return false; else return true; #endif } return false; } static int fou_add_to_port_list(struct net *net, struct fou *fou, struct fou_cfg *cfg) { struct fou_net *fn = net_generic(net, fou_net_id); struct fou *fout; mutex_lock(&fn->fou_lock); list_for_each_entry(fout, &fn->fou_list, list) { if (fou_cfg_cmp(fout, cfg)) { mutex_unlock(&fn->fou_lock); return -EALREADY; } } list_add(&fou->list, &fn->fou_list); mutex_unlock(&fn->fou_lock); return 0; } static void fou_release(struct fou *fou) { struct socket *sock = fou->sock; list_del(&fou->list); udp_tunnel_sock_release(sock); kfree_rcu(fou, rcu); } static int fou_create(struct net *net, struct fou_cfg *cfg, struct socket **sockp) { struct socket *sock = NULL; struct fou *fou = NULL; struct sock *sk; struct udp_tunnel_sock_cfg tunnel_cfg; int err; /* Open UDP socket */ err = udp_sock_create(net, &cfg->udp_config, &sock); if (err < 0) goto error; /* Allocate FOU port structure */ fou = kzalloc(sizeof(*fou), GFP_KERNEL); if (!fou) { err = -ENOMEM; goto error; } sk = sock->sk; fou->port = cfg->udp_config.local_udp_port; fou->family = cfg->udp_config.family; fou->flags = cfg->flags; fou->type = cfg->type; fou->sock = sock; memset(&tunnel_cfg, 0, sizeof(tunnel_cfg)); tunnel_cfg.encap_type = 1; tunnel_cfg.sk_user_data = fou; tunnel_cfg.encap_destroy = NULL; /* Initial for fou type */ switch (cfg->type) { case FOU_ENCAP_DIRECT: tunnel_cfg.encap_rcv = fou_udp_recv; tunnel_cfg.gro_receive = fou_gro_receive; tunnel_cfg.gro_complete = fou_gro_complete; fou->protocol = cfg->protocol; break; case FOU_ENCAP_GUE: tunnel_cfg.encap_rcv = gue_udp_recv; tunnel_cfg.gro_receive = gue_gro_receive; tunnel_cfg.gro_complete = gue_gro_complete; break; default: err = -EINVAL; goto error; } setup_udp_tunnel_sock(net, sock, &tunnel_cfg); sk->sk_allocation = GFP_ATOMIC; err = fou_add_to_port_list(net, fou, cfg); if (err) goto error; if (sockp) *sockp = sock; return 0; error: kfree(fou); if (sock) udp_tunnel_sock_release(sock); return err; } static int fou_destroy(struct net *net, struct fou_cfg *cfg) { struct fou_net *fn = net_generic(net, fou_net_id); int err = -EINVAL; struct fou *fou; mutex_lock(&fn->fou_lock); list_for_each_entry(fou, &fn->fou_list, list) { if (fou_cfg_cmp(fou, cfg)) { fou_release(fou); err = 0; break; } } mutex_unlock(&fn->fou_lock); return err; } static struct genl_family fou_nl_family; static int parse_nl_config(struct genl_info *info, struct fou_cfg *cfg) { bool has_local = false, has_peer = false; struct nlattr *attr; int ifindex; __be16 port; memset(cfg, 0, sizeof(*cfg)); cfg->udp_config.family = AF_INET; if (info->attrs[FOU_ATTR_AF]) { u8 family = nla_get_u8(info->attrs[FOU_ATTR_AF]); switch (family) { case AF_INET: break; case AF_INET6: cfg->udp_config.ipv6_v6only = 1; break; default: return -EAFNOSUPPORT; } cfg->udp_config.family = family; } if (info->attrs[FOU_ATTR_PORT]) { port = nla_get_be16(info->attrs[FOU_ATTR_PORT]); cfg->udp_config.local_udp_port = port; } if (info->attrs[FOU_ATTR_IPPROTO]) cfg->protocol = nla_get_u8(info->attrs[FOU_ATTR_IPPROTO]); if (info->attrs[FOU_ATTR_TYPE]) cfg->type = nla_get_u8(info->attrs[FOU_ATTR_TYPE]); if (info->attrs[FOU_ATTR_REMCSUM_NOPARTIAL]) cfg->flags |= FOU_F_REMCSUM_NOPARTIAL; if (cfg->udp_config.family == AF_INET) { if (info->attrs[FOU_ATTR_LOCAL_V4]) { attr = info->attrs[FOU_ATTR_LOCAL_V4]; cfg->udp_config.local_ip.s_addr = nla_get_in_addr(attr); has_local = true; } if (info->attrs[FOU_ATTR_PEER_V4]) { attr = info->attrs[FOU_ATTR_PEER_V4]; cfg->udp_config.peer_ip.s_addr = nla_get_in_addr(attr); has_peer = true; } #if IS_ENABLED(CONFIG_IPV6) } else { if (info->attrs[FOU_ATTR_LOCAL_V6]) { attr = info->attrs[FOU_ATTR_LOCAL_V6]; cfg->udp_config.local_ip6 = nla_get_in6_addr(attr); has_local = true; } if (info->attrs[FOU_ATTR_PEER_V6]) { attr = info->attrs[FOU_ATTR_PEER_V6]; cfg->udp_config.peer_ip6 = nla_get_in6_addr(attr); has_peer = true; } #endif } if (has_peer) { if (info->attrs[FOU_ATTR_PEER_PORT]) { port = nla_get_be16(info->attrs[FOU_ATTR_PEER_PORT]); cfg->udp_config.peer_udp_port = port; } else { return -EINVAL; } } if (info->attrs[FOU_ATTR_IFINDEX]) { if (!has_local) return -EINVAL; ifindex = nla_get_s32(info->attrs[FOU_ATTR_IFINDEX]); cfg->udp_config.bind_ifindex = ifindex; } return 0; } int fou_nl_add_doit(struct sk_buff *skb, struct genl_info *info) { struct net *net = genl_info_net(info); struct fou_cfg cfg; int err; err = parse_nl_config(info, &cfg); if (err) return err; return fou_create(net, &cfg, NULL); } int fou_nl_del_doit(struct sk_buff *skb, struct genl_info *info) { struct net *net = genl_info_net(info); struct fou_cfg cfg; int err; err = parse_nl_config(info, &cfg); if (err) return err; return fou_destroy(net, &cfg); } static int fou_fill_info(struct fou *fou, struct sk_buff *msg) { struct sock *sk = fou->sock->sk; if (nla_put_u8(msg, FOU_ATTR_AF, fou->sock->sk->sk_family) || nla_put_be16(msg, FOU_ATTR_PORT, fou->port) || nla_put_be16(msg, FOU_ATTR_PEER_PORT, sk->sk_dport) || nla_put_u8(msg, FOU_ATTR_IPPROTO, fou->protocol) || nla_put_u8(msg, FOU_ATTR_TYPE, fou->type) || nla_put_s32(msg, FOU_ATTR_IFINDEX, sk->sk_bound_dev_if)) return -1; if (fou->flags & FOU_F_REMCSUM_NOPARTIAL) if (nla_put_flag(msg, FOU_ATTR_REMCSUM_NOPARTIAL)) return -1; if (fou->sock->sk->sk_family == AF_INET) { if (nla_put_in_addr(msg, FOU_ATTR_LOCAL_V4, sk->sk_rcv_saddr)) return -1; if (nla_put_in_addr(msg, FOU_ATTR_PEER_V4, sk->sk_daddr)) return -1; #if IS_ENABLED(CONFIG_IPV6) } else { if (nla_put_in6_addr(msg, FOU_ATTR_LOCAL_V6, &sk->sk_v6_rcv_saddr)) return -1; if (nla_put_in6_addr(msg, FOU_ATTR_PEER_V6, &sk->sk_v6_daddr)) return -1; #endif } return 0; } static int fou_dump_info(struct fou *fou, u32 portid, u32 seq, u32 flags, struct sk_buff *skb, u8 cmd) { void *hdr; hdr = genlmsg_put(skb, portid, seq, &fou_nl_family, flags, cmd); if (!hdr) return -ENOMEM; if (fou_fill_info(fou, skb) < 0) goto nla_put_failure; genlmsg_end(skb, hdr); return 0; nla_put_failure: genlmsg_cancel(skb, hdr); return -EMSGSIZE; } int fou_nl_get_doit(struct sk_buff *skb, struct genl_info *info) { struct net *net = genl_info_net(info); struct fou_net *fn = net_generic(net, fou_net_id); struct sk_buff *msg; struct fou_cfg cfg; struct fou *fout; __be16 port; u8 family; int ret; ret = parse_nl_config(info, &cfg); if (ret) return ret; port = cfg.udp_config.local_udp_port; if (port == 0) return -EINVAL; family = cfg.udp_config.family; if (family != AF_INET && family != AF_INET6) return -EINVAL; msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!msg) return -ENOMEM; ret = -ESRCH; mutex_lock(&fn->fou_lock); list_for_each_entry(fout, &fn->fou_list, list) { if (fou_cfg_cmp(fout, &cfg)) { ret = fou_dump_info(fout, info->snd_portid, info->snd_seq, 0, msg, info->genlhdr->cmd); break; } } mutex_unlock(&fn->fou_lock); if (ret < 0) goto out_free; return genlmsg_reply(msg, info); out_free: nlmsg_free(msg); return ret; } int fou_nl_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb) { struct net *net = sock_net(skb->sk); struct fou_net *fn = net_generic(net, fou_net_id); struct fou *fout; int idx = 0, ret; mutex_lock(&fn->fou_lock); list_for_each_entry(fout, &fn->fou_list, list) { if (idx++ < cb->args[0]) continue; ret = fou_dump_info(fout, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, skb, FOU_CMD_GET); if (ret) break; } mutex_unlock(&fn->fou_lock); cb->args[0] = idx; return skb->len; } static struct genl_family fou_nl_family __ro_after_init = { .hdrsize = 0, .name = FOU_GENL_NAME, .version = FOU_GENL_VERSION, .maxattr = FOU_ATTR_MAX, .policy = fou_nl_policy, .netnsok = true, .module = THIS_MODULE, .small_ops = fou_nl_ops, .n_small_ops = ARRAY_SIZE(fou_nl_ops), .resv_start_op = FOU_CMD_GET + 1, }; size_t fou_encap_hlen(struct ip_tunnel_encap *e) { return sizeof(struct udphdr); } EXPORT_SYMBOL(fou_encap_hlen); size_t gue_encap_hlen(struct ip_tunnel_encap *e) { size_t len; bool need_priv = false; len = sizeof(struct udphdr) + sizeof(struct guehdr); if (e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) { len += GUE_PLEN_REMCSUM; need_priv = true; } len += need_priv ? GUE_LEN_PRIV : 0; return len; } EXPORT_SYMBOL(gue_encap_hlen); int __fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e, u8 *protocol, __be16 *sport, int type) { int err; err = iptunnel_handle_offloads(skb, type); if (err) return err; *sport = e->sport ? : udp_flow_src_port(dev_net(skb->dev), skb, 0, 0, false); return 0; } EXPORT_SYMBOL(__fou_build_header); int __gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e, u8 *protocol, __be16 *sport, int type) { struct guehdr *guehdr; size_t hdrlen, optlen = 0; void *data; bool need_priv = false; int err; if ((e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) && skb->ip_summed == CHECKSUM_PARTIAL) { optlen += GUE_PLEN_REMCSUM; type |= SKB_GSO_TUNNEL_REMCSUM; need_priv = true; } optlen += need_priv ? GUE_LEN_PRIV : 0; err = iptunnel_handle_offloads(skb, type); if (err) return err; /* Get source port (based on flow hash) before skb_push */ *sport = e->sport ? : udp_flow_src_port(dev_net(skb->dev), skb, 0, 0, false); hdrlen = sizeof(struct guehdr) + optlen; skb_push(skb, hdrlen); guehdr = (struct guehdr *)skb->data; guehdr->control = 0; guehdr->version = 0; guehdr->hlen = optlen >> 2; guehdr->flags = 0; guehdr->proto_ctype = *protocol; data = &guehdr[1]; if (need_priv) { __be32 *flags = data; guehdr->flags |= GUE_FLAG_PRIV; *flags = 0; data += GUE_LEN_PRIV; if (type & SKB_GSO_TUNNEL_REMCSUM) { u16 csum_start = skb_checksum_start_offset(skb); __be16 *pd = data; if (csum_start < hdrlen) return -EINVAL; csum_start -= hdrlen; pd[0] = htons(csum_start); pd[1] = htons(csum_start + skb->csum_offset); if (!skb_is_gso(skb)) { skb->ip_summed = CHECKSUM_NONE; skb->encapsulation = 0; } *flags |= GUE_PFLAG_REMCSUM; data += GUE_PLEN_REMCSUM; } } return 0; } EXPORT_SYMBOL(__gue_build_header); #ifdef CONFIG_NET_FOU_IP_TUNNELS static void fou_build_udp(struct sk_buff *skb, struct ip_tunnel_encap *e, struct flowi4 *fl4, u8 *protocol, __be16 sport) { struct udphdr *uh; skb_push(skb, sizeof(struct udphdr)); skb_reset_transport_header(skb); uh = udp_hdr(skb); uh->dest = e->dport; uh->source = sport; uh->len = htons(skb->len); udp_set_csum(!(e->flags & TUNNEL_ENCAP_FLAG_CSUM), skb, fl4->saddr, fl4->daddr, skb->len); *protocol = IPPROTO_UDP; } static int fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e, u8 *protocol, struct flowi4 *fl4) { int type = e->flags & TUNNEL_ENCAP_FLAG_CSUM ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL; __be16 sport; int err; err = __fou_build_header(skb, e, protocol, &sport, type); if (err) return err; fou_build_udp(skb, e, fl4, protocol, sport); return 0; } static int gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e, u8 *protocol, struct flowi4 *fl4) { int type = e->flags & TUNNEL_ENCAP_FLAG_CSUM ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL; __be16 sport; int err; err = __gue_build_header(skb, e, protocol, &sport, type); if (err) return err; fou_build_udp(skb, e, fl4, protocol, sport); return 0; } static int gue_err_proto_handler(int proto, struct sk_buff *skb, u32 info) { const struct net_protocol *ipprot = rcu_dereference(inet_protos[proto]); if (ipprot && ipprot->err_handler) { if (!ipprot->err_handler(skb, info)) return 0; } return -ENOENT; } static int gue_err(struct sk_buff *skb, u32 info) { int transport_offset = skb_transport_offset(skb); struct guehdr *guehdr; size_t len, optlen; int ret; len = sizeof(struct udphdr) + sizeof(struct guehdr); if (!pskb_may_pull(skb, transport_offset + len)) return -EINVAL; guehdr = (struct guehdr *)&udp_hdr(skb)[1]; switch (guehdr->version) { case 0: /* Full GUE header present */ break; case 1: { /* Direct encapsulation of IPv4 or IPv6 */ skb_set_transport_header(skb, -(int)sizeof(struct icmphdr)); switch (((struct iphdr *)guehdr)->version) { case 4: ret = gue_err_proto_handler(IPPROTO_IPIP, skb, info); goto out; #if IS_ENABLED(CONFIG_IPV6) case 6: ret = gue_err_proto_handler(IPPROTO_IPV6, skb, info); goto out; #endif default: ret = -EOPNOTSUPP; goto out; } } default: /* Undefined version */ return -EOPNOTSUPP; } if (guehdr->control) return -ENOENT; optlen = guehdr->hlen << 2; if (!pskb_may_pull(skb, transport_offset + len + optlen)) return -EINVAL; guehdr = (struct guehdr *)&udp_hdr(skb)[1]; if (validate_gue_flags(guehdr, optlen)) return -EINVAL; /* Handling exceptions for direct UDP encapsulation in GUE would lead to * recursion. Besides, this kind of encapsulation can't even be * configured currently. Discard this. */ if (guehdr->proto_ctype == IPPROTO_UDP || guehdr->proto_ctype == IPPROTO_UDPLITE) return -EOPNOTSUPP; skb_set_transport_header(skb, -(int)sizeof(struct icmphdr)); ret = gue_err_proto_handler(guehdr->proto_ctype, skb, info); out: skb_set_transport_header(skb, transport_offset); return ret; } static const struct ip_tunnel_encap_ops fou_iptun_ops = { .encap_hlen = fou_encap_hlen, .build_header = fou_build_header, .err_handler = gue_err, }; static const struct ip_tunnel_encap_ops gue_iptun_ops = { .encap_hlen = gue_encap_hlen, .build_header = gue_build_header, .err_handler = gue_err, }; static int ip_tunnel_encap_add_fou_ops(void) { int ret; ret = ip_tunnel_encap_add_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU); if (ret < 0) { pr_err("can't add fou ops\n"); return ret; } ret = ip_tunnel_encap_add_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE); if (ret < 0) { pr_err("can't add gue ops\n"); ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU); return ret; } return 0; } static void ip_tunnel_encap_del_fou_ops(void) { ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU); ip_tunnel_encap_del_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE); } #else static int ip_tunnel_encap_add_fou_ops(void) { return 0; } static void ip_tunnel_encap_del_fou_ops(void) { } #endif static __net_init int fou_init_net(struct net *net) { struct fou_net *fn = net_generic(net, fou_net_id); INIT_LIST_HEAD(&fn->fou_list); mutex_init(&fn->fou_lock); return 0; } static __net_exit void fou_exit_net(struct net *net) { struct fou_net *fn = net_generic(net, fou_net_id); struct fou *fou, *next; /* Close all the FOU sockets */ mutex_lock(&fn->fou_lock); list_for_each_entry_safe(fou, next, &fn->fou_list, list) fou_release(fou); mutex_unlock(&fn->fou_lock); } static struct pernet_operations fou_net_ops = { .init = fou_init_net, .exit = fou_exit_net, .id = &fou_net_id, .size = sizeof(struct fou_net), }; static int __init fou_init(void) { int ret; ret = register_pernet_device(&fou_net_ops); if (ret) goto exit; ret = genl_register_family(&fou_nl_family); if (ret < 0) goto unregister; ret = register_fou_bpf(); if (ret < 0) goto kfunc_failed; ret = ip_tunnel_encap_add_fou_ops(); if (ret == 0) return 0; kfunc_failed: genl_unregister_family(&fou_nl_family); unregister: unregister_pernet_device(&fou_net_ops); exit: return ret; } static void __exit fou_fini(void) { ip_tunnel_encap_del_fou_ops(); genl_unregister_family(&fou_nl_family); unregister_pernet_device(&fou_net_ops); } module_init(fou_init); module_exit(fou_fini); MODULE_AUTHOR("Tom Herbert <[email protected]>"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Foo over UDP");
linux-master
net/ipv4/fou_core.c
// SPDX-License-Identifier: GPL-2.0 /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * The IP to API glue. * * Authors: see ip.c * * Fixes: * Many : Split from ip.c , see ip.c for history. * Martin Mares : TOS setting fixed. * Alan Cox : Fixed a couple of oopses in Martin's * TOS tweaks. * Mike McLagan : Routing by source */ #include <linux/module.h> #include <linux/types.h> #include <linux/mm.h> #include <linux/skbuff.h> #include <linux/ip.h> #include <linux/icmp.h> #include <linux/inetdevice.h> #include <linux/netdevice.h> #include <linux/slab.h> #include <net/sock.h> #include <net/ip.h> #include <net/icmp.h> #include <net/tcp_states.h> #include <linux/udp.h> #include <linux/igmp.h> #include <linux/netfilter.h> #include <linux/route.h> #include <linux/mroute.h> #include <net/inet_ecn.h> #include <net/route.h> #include <net/xfrm.h> #include <net/compat.h> #include <net/checksum.h> #if IS_ENABLED(CONFIG_IPV6) #include <net/transp_v6.h> #endif #include <net/ip_fib.h> #include <linux/errqueue.h> #include <linux/uaccess.h> #include <linux/bpfilter.h> /* * SOL_IP control messages. */ static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) { struct in_pktinfo info = *PKTINFO_SKB_CB(skb); info.ipi_addr.s_addr = ip_hdr(skb)->daddr; put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info); } static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb) { int ttl = ip_hdr(skb)->ttl; put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl); } static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb) { put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos); } static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb) { if (IPCB(skb)->opt.optlen == 0) return; put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen, ip_hdr(skb) + 1); } static void ip_cmsg_recv_retopts(struct net *net, struct msghdr *msg, struct sk_buff *skb) { unsigned char optbuf[sizeof(struct ip_options) + 40]; struct ip_options *opt = (struct ip_options *)optbuf; if (IPCB(skb)->opt.optlen == 0) return; if (ip_options_echo(net, opt, skb)) { msg->msg_flags |= MSG_CTRUNC; return; } ip_options_undo(opt); put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data); } static void ip_cmsg_recv_fragsize(struct msghdr *msg, struct sk_buff *skb) { int val; if (IPCB(skb)->frag_max_size == 0) return; val = IPCB(skb)->frag_max_size; put_cmsg(msg, SOL_IP, IP_RECVFRAGSIZE, sizeof(val), &val); } static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb, int tlen, int offset) { __wsum csum = skb->csum; if (skb->ip_summed != CHECKSUM_COMPLETE) return; if (offset != 0) { int tend_off = skb_transport_offset(skb) + tlen; csum = csum_sub(csum, skb_checksum(skb, tend_off, offset, 0)); } put_cmsg(msg, SOL_IP, IP_CHECKSUM, sizeof(__wsum), &csum); } static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb) { char *secdata; u32 seclen, secid; int err; err = security_socket_getpeersec_dgram(NULL, skb, &secid); if (err) return; err = security_secid_to_secctx(secid, &secdata, &seclen); if (err) return; put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata); security_release_secctx(secdata, seclen); } static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb) { __be16 _ports[2], *ports; struct sockaddr_in sin; /* All current transport protocols have the port numbers in the * first four bytes of the transport header and this function is * written with this assumption in mind. */ ports = skb_header_pointer(skb, skb_transport_offset(skb), sizeof(_ports), &_ports); if (!ports) return; sin.sin_family = AF_INET; sin.sin_addr.s_addr = ip_hdr(skb)->daddr; sin.sin_port = ports[1]; memset(sin.sin_zero, 0, sizeof(sin.sin_zero)); put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin); } void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk, struct sk_buff *skb, int tlen, int offset) { unsigned long flags = inet_cmsg_flags(inet_sk(sk)); if (!flags) return; /* Ordered by supposed usage frequency */ if (flags & IP_CMSG_PKTINFO) { ip_cmsg_recv_pktinfo(msg, skb); flags &= ~IP_CMSG_PKTINFO; if (!flags) return; } if (flags & IP_CMSG_TTL) { ip_cmsg_recv_ttl(msg, skb); flags &= ~IP_CMSG_TTL; if (!flags) return; } if (flags & IP_CMSG_TOS) { ip_cmsg_recv_tos(msg, skb); flags &= ~IP_CMSG_TOS; if (!flags) return; } if (flags & IP_CMSG_RECVOPTS) { ip_cmsg_recv_opts(msg, skb); flags &= ~IP_CMSG_RECVOPTS; if (!flags) return; } if (flags & IP_CMSG_RETOPTS) { ip_cmsg_recv_retopts(sock_net(sk), msg, skb); flags &= ~IP_CMSG_RETOPTS; if (!flags) return; } if (flags & IP_CMSG_PASSSEC) { ip_cmsg_recv_security(msg, skb); flags &= ~IP_CMSG_PASSSEC; if (!flags) return; } if (flags & IP_CMSG_ORIGDSTADDR) { ip_cmsg_recv_dstaddr(msg, skb); flags &= ~IP_CMSG_ORIGDSTADDR; if (!flags) return; } if (flags & IP_CMSG_CHECKSUM) ip_cmsg_recv_checksum(msg, skb, tlen, offset); if (flags & IP_CMSG_RECVFRAGSIZE) ip_cmsg_recv_fragsize(msg, skb); } EXPORT_SYMBOL(ip_cmsg_recv_offset); int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc, bool allow_ipv6) { int err, val; struct cmsghdr *cmsg; struct net *net = sock_net(sk); for_each_cmsghdr(cmsg, msg) { if (!CMSG_OK(msg, cmsg)) return -EINVAL; #if IS_ENABLED(CONFIG_IPV6) if (allow_ipv6 && cmsg->cmsg_level == SOL_IPV6 && cmsg->cmsg_type == IPV6_PKTINFO) { struct in6_pktinfo *src_info; if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info))) return -EINVAL; src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg); if (!ipv6_addr_v4mapped(&src_info->ipi6_addr)) return -EINVAL; if (src_info->ipi6_ifindex) ipc->oif = src_info->ipi6_ifindex; ipc->addr = src_info->ipi6_addr.s6_addr32[3]; continue; } #endif if (cmsg->cmsg_level == SOL_SOCKET) { err = __sock_cmsg_send(sk, cmsg, &ipc->sockc); if (err) return err; continue; } if (cmsg->cmsg_level != SOL_IP) continue; switch (cmsg->cmsg_type) { case IP_RETOPTS: err = cmsg->cmsg_len - sizeof(struct cmsghdr); /* Our caller is responsible for freeing ipc->opt */ err = ip_options_get(net, &ipc->opt, KERNEL_SOCKPTR(CMSG_DATA(cmsg)), err < 40 ? err : 40); if (err) return err; break; case IP_PKTINFO: { struct in_pktinfo *info; if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo))) return -EINVAL; info = (struct in_pktinfo *)CMSG_DATA(cmsg); if (info->ipi_ifindex) ipc->oif = info->ipi_ifindex; ipc->addr = info->ipi_spec_dst.s_addr; break; } case IP_TTL: if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) return -EINVAL; val = *(int *)CMSG_DATA(cmsg); if (val < 1 || val > 255) return -EINVAL; ipc->ttl = val; break; case IP_TOS: if (cmsg->cmsg_len == CMSG_LEN(sizeof(int))) val = *(int *)CMSG_DATA(cmsg); else if (cmsg->cmsg_len == CMSG_LEN(sizeof(u8))) val = *(u8 *)CMSG_DATA(cmsg); else return -EINVAL; if (val < 0 || val > 255) return -EINVAL; ipc->tos = val; ipc->priority = rt_tos2priority(ipc->tos); break; case IP_PROTOCOL: if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) return -EINVAL; val = *(int *)CMSG_DATA(cmsg); if (val < 1 || val > 255) return -EINVAL; ipc->protocol = val; break; default: return -EINVAL; } } return 0; } static void ip_ra_destroy_rcu(struct rcu_head *head) { struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu); sock_put(ra->saved_sk); kfree(ra); } int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *)) { struct ip_ra_chain *ra, *new_ra; struct ip_ra_chain __rcu **rap; struct net *net = sock_net(sk); if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW) return -EINVAL; new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL; if (on && !new_ra) return -ENOMEM; mutex_lock(&net->ipv4.ra_mutex); for (rap = &net->ipv4.ra_chain; (ra = rcu_dereference_protected(*rap, lockdep_is_held(&net->ipv4.ra_mutex))) != NULL; rap = &ra->next) { if (ra->sk == sk) { if (on) { mutex_unlock(&net->ipv4.ra_mutex); kfree(new_ra); return -EADDRINUSE; } /* dont let ip_call_ra_chain() use sk again */ ra->sk = NULL; RCU_INIT_POINTER(*rap, ra->next); mutex_unlock(&net->ipv4.ra_mutex); if (ra->destructor) ra->destructor(sk); /* * Delay sock_put(sk) and kfree(ra) after one rcu grace * period. This guarantee ip_call_ra_chain() dont need * to mess with socket refcounts. */ ra->saved_sk = sk; call_rcu(&ra->rcu, ip_ra_destroy_rcu); return 0; } } if (!new_ra) { mutex_unlock(&net->ipv4.ra_mutex); return -ENOBUFS; } new_ra->sk = sk; new_ra->destructor = destructor; RCU_INIT_POINTER(new_ra->next, ra); rcu_assign_pointer(*rap, new_ra); sock_hold(sk); mutex_unlock(&net->ipv4.ra_mutex); return 0; } static void ipv4_icmp_error_rfc4884(const struct sk_buff *skb, struct sock_ee_data_rfc4884 *out) { switch (icmp_hdr(skb)->type) { case ICMP_DEST_UNREACH: case ICMP_TIME_EXCEEDED: case ICMP_PARAMETERPROB: ip_icmp_error_rfc4884(skb, out, sizeof(struct icmphdr), icmp_hdr(skb)->un.reserved[1] * 4); } } void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, u32 info, u8 *payload) { struct sock_exterr_skb *serr; skb = skb_clone(skb, GFP_ATOMIC); if (!skb) return; serr = SKB_EXT_ERR(skb); serr->ee.ee_errno = err; serr->ee.ee_origin = SO_EE_ORIGIN_ICMP; serr->ee.ee_type = icmp_hdr(skb)->type; serr->ee.ee_code = icmp_hdr(skb)->code; serr->ee.ee_pad = 0; serr->ee.ee_info = info; serr->ee.ee_data = 0; serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) - skb_network_header(skb); serr->port = port; if (skb_pull(skb, payload - skb->data)) { if (inet_test_bit(RECVERR_RFC4884, sk)) ipv4_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884); skb_reset_transport_header(skb); if (sock_queue_err_skb(sk, skb) == 0) return; } kfree_skb(skb); } EXPORT_SYMBOL_GPL(ip_icmp_error); void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info) { struct sock_exterr_skb *serr; struct iphdr *iph; struct sk_buff *skb; if (!inet_test_bit(RECVERR, sk)) return; skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC); if (!skb) return; skb_put(skb, sizeof(struct iphdr)); skb_reset_network_header(skb); iph = ip_hdr(skb); iph->daddr = daddr; serr = SKB_EXT_ERR(skb); serr->ee.ee_errno = err; serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; serr->ee.ee_type = 0; serr->ee.ee_code = 0; serr->ee.ee_pad = 0; serr->ee.ee_info = info; serr->ee.ee_data = 0; serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb); serr->port = port; __skb_pull(skb, skb_tail_pointer(skb) - skb->data); skb_reset_transport_header(skb); if (sock_queue_err_skb(sk, skb)) kfree_skb(skb); } /* For some errors we have valid addr_offset even with zero payload and * zero port. Also, addr_offset should be supported if port is set. */ static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr) { return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port; } /* IPv4 supports cmsg on all imcp errors and some timestamps * * Timestamp code paths do not initialize the fields expected by cmsg: * the PKTINFO fields in skb->cb[]. Fill those in here. */ static bool ipv4_datagram_support_cmsg(const struct sock *sk, struct sk_buff *skb, int ee_origin) { struct in_pktinfo *info; if (ee_origin == SO_EE_ORIGIN_ICMP) return true; if (ee_origin == SO_EE_ORIGIN_LOCAL) return false; /* Support IP_PKTINFO on tstamp packets if requested, to correlate * timestamp with egress dev. Not possible for packets without iif * or without payload (SOF_TIMESTAMPING_OPT_TSONLY). */ info = PKTINFO_SKB_CB(skb); if (!(READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_OPT_CMSG) || !info->ipi_ifindex) return false; info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr; return true; } /* * Handle MSG_ERRQUEUE */ int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) { struct sock_exterr_skb *serr; struct sk_buff *skb; DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); struct { struct sock_extended_err ee; struct sockaddr_in offender; } errhdr; int err; int copied; err = -EAGAIN; skb = sock_dequeue_err_skb(sk); if (!skb) goto out; copied = skb->len; if (copied > len) { msg->msg_flags |= MSG_TRUNC; copied = len; } err = skb_copy_datagram_msg(skb, 0, msg, copied); if (unlikely(err)) { kfree_skb(skb); return err; } sock_recv_timestamp(msg, sk, skb); serr = SKB_EXT_ERR(skb); if (sin && ipv4_datagram_support_addr(serr)) { sin->sin_family = AF_INET; sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) + serr->addr_offset); sin->sin_port = serr->port; memset(&sin->sin_zero, 0, sizeof(sin->sin_zero)); *addr_len = sizeof(*sin); } memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); sin = &errhdr.offender; memset(sin, 0, sizeof(*sin)); if (ipv4_datagram_support_cmsg(sk, skb, serr->ee.ee_origin)) { sin->sin_family = AF_INET; sin->sin_addr.s_addr = ip_hdr(skb)->saddr; if (inet_cmsg_flags(inet_sk(sk))) ip_cmsg_recv(msg, skb); } put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr); /* Now we could try to dump offended packet options */ msg->msg_flags |= MSG_ERRQUEUE; err = copied; consume_skb(skb); out: return err; } void __ip_sock_set_tos(struct sock *sk, int val) { if (sk->sk_type == SOCK_STREAM) { val &= ~INET_ECN_MASK; val |= inet_sk(sk)->tos & INET_ECN_MASK; } if (inet_sk(sk)->tos != val) { inet_sk(sk)->tos = val; WRITE_ONCE(sk->sk_priority, rt_tos2priority(val)); sk_dst_reset(sk); } } void ip_sock_set_tos(struct sock *sk, int val) { lock_sock(sk); __ip_sock_set_tos(sk, val); release_sock(sk); } EXPORT_SYMBOL(ip_sock_set_tos); void ip_sock_set_freebind(struct sock *sk) { inet_set_bit(FREEBIND, sk); } EXPORT_SYMBOL(ip_sock_set_freebind); void ip_sock_set_recverr(struct sock *sk) { inet_set_bit(RECVERR, sk); } EXPORT_SYMBOL(ip_sock_set_recverr); int ip_sock_set_mtu_discover(struct sock *sk, int val) { if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT) return -EINVAL; lock_sock(sk); inet_sk(sk)->pmtudisc = val; release_sock(sk); return 0; } EXPORT_SYMBOL(ip_sock_set_mtu_discover); void ip_sock_set_pktinfo(struct sock *sk) { inet_set_bit(PKTINFO, sk); } EXPORT_SYMBOL(ip_sock_set_pktinfo); /* * Socket option code for IP. This is the end of the line after any * TCP,UDP etc options on an IP socket. */ static bool setsockopt_needs_rtnl(int optname) { switch (optname) { case IP_ADD_MEMBERSHIP: case IP_ADD_SOURCE_MEMBERSHIP: case IP_BLOCK_SOURCE: case IP_DROP_MEMBERSHIP: case IP_DROP_SOURCE_MEMBERSHIP: case IP_MSFILTER: case IP_UNBLOCK_SOURCE: case MCAST_BLOCK_SOURCE: case MCAST_MSFILTER: case MCAST_JOIN_GROUP: case MCAST_JOIN_SOURCE_GROUP: case MCAST_LEAVE_GROUP: case MCAST_LEAVE_SOURCE_GROUP: case MCAST_UNBLOCK_SOURCE: return true; } return false; } static int set_mcast_msfilter(struct sock *sk, int ifindex, int numsrc, int fmode, struct sockaddr_storage *group, struct sockaddr_storage *list) { struct ip_msfilter *msf; struct sockaddr_in *psin; int err, i; msf = kmalloc(IP_MSFILTER_SIZE(numsrc), GFP_KERNEL); if (!msf) return -ENOBUFS; psin = (struct sockaddr_in *)group; if (psin->sin_family != AF_INET) goto Eaddrnotavail; msf->imsf_multiaddr = psin->sin_addr.s_addr; msf->imsf_interface = 0; msf->imsf_fmode = fmode; msf->imsf_numsrc = numsrc; for (i = 0; i < numsrc; ++i) { psin = (struct sockaddr_in *)&list[i]; if (psin->sin_family != AF_INET) goto Eaddrnotavail; msf->imsf_slist_flex[i] = psin->sin_addr.s_addr; } err = ip_mc_msfilter(sk, msf, ifindex); kfree(msf); return err; Eaddrnotavail: kfree(msf); return -EADDRNOTAVAIL; } static int copy_group_source_from_sockptr(struct group_source_req *greqs, sockptr_t optval, int optlen) { if (in_compat_syscall()) { struct compat_group_source_req gr32; if (optlen != sizeof(gr32)) return -EINVAL; if (copy_from_sockptr(&gr32, optval, sizeof(gr32))) return -EFAULT; greqs->gsr_interface = gr32.gsr_interface; greqs->gsr_group = gr32.gsr_group; greqs->gsr_source = gr32.gsr_source; } else { if (optlen != sizeof(*greqs)) return -EINVAL; if (copy_from_sockptr(greqs, optval, sizeof(*greqs))) return -EFAULT; } return 0; } static int do_mcast_group_source(struct sock *sk, int optname, sockptr_t optval, int optlen) { struct group_source_req greqs; struct ip_mreq_source mreqs; struct sockaddr_in *psin; int omode, add, err; err = copy_group_source_from_sockptr(&greqs, optval, optlen); if (err) return err; if (greqs.gsr_group.ss_family != AF_INET || greqs.gsr_source.ss_family != AF_INET) return -EADDRNOTAVAIL; psin = (struct sockaddr_in *)&greqs.gsr_group; mreqs.imr_multiaddr = psin->sin_addr.s_addr; psin = (struct sockaddr_in *)&greqs.gsr_source; mreqs.imr_sourceaddr = psin->sin_addr.s_addr; mreqs.imr_interface = 0; /* use index for mc_source */ if (optname == MCAST_BLOCK_SOURCE) { omode = MCAST_EXCLUDE; add = 1; } else if (optname == MCAST_UNBLOCK_SOURCE) { omode = MCAST_EXCLUDE; add = 0; } else if (optname == MCAST_JOIN_SOURCE_GROUP) { struct ip_mreqn mreq; psin = (struct sockaddr_in *)&greqs.gsr_group; mreq.imr_multiaddr = psin->sin_addr; mreq.imr_address.s_addr = 0; mreq.imr_ifindex = greqs.gsr_interface; err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE); if (err && err != -EADDRINUSE) return err; greqs.gsr_interface = mreq.imr_ifindex; omode = MCAST_INCLUDE; add = 1; } else /* MCAST_LEAVE_SOURCE_GROUP */ { omode = MCAST_INCLUDE; add = 0; } return ip_mc_source(add, omode, sk, &mreqs, greqs.gsr_interface); } static int ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, int optlen) { struct group_filter *gsf = NULL; int err; if (optlen < GROUP_FILTER_SIZE(0)) return -EINVAL; if (optlen > READ_ONCE(sysctl_optmem_max)) return -ENOBUFS; gsf = memdup_sockptr(optval, optlen); if (IS_ERR(gsf)) return PTR_ERR(gsf); /* numsrc >= (4G-140)/128 overflow in 32 bits */ err = -ENOBUFS; if (gsf->gf_numsrc >= 0x1ffffff || gsf->gf_numsrc > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf)) goto out_free_gsf; err = -EINVAL; if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) goto out_free_gsf; err = set_mcast_msfilter(sk, gsf->gf_interface, gsf->gf_numsrc, gsf->gf_fmode, &gsf->gf_group, gsf->gf_slist_flex); out_free_gsf: kfree(gsf); return err; } static int compat_ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, int optlen) { const int size0 = offsetof(struct compat_group_filter, gf_slist_flex); struct compat_group_filter *gf32; unsigned int n; void *p; int err; if (optlen < size0) return -EINVAL; if (optlen > READ_ONCE(sysctl_optmem_max) - 4) return -ENOBUFS; p = kmalloc(optlen + 4, GFP_KERNEL); if (!p) return -ENOMEM; gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */ err = -EFAULT; if (copy_from_sockptr(gf32, optval, optlen)) goto out_free_gsf; /* numsrc >= (4G-140)/128 overflow in 32 bits */ n = gf32->gf_numsrc; err = -ENOBUFS; if (n >= 0x1ffffff) goto out_free_gsf; err = -EINVAL; if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen) goto out_free_gsf; /* numsrc >= (4G-140)/128 overflow in 32 bits */ err = -ENOBUFS; if (n > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf)) goto out_free_gsf; err = set_mcast_msfilter(sk, gf32->gf_interface, n, gf32->gf_fmode, &gf32->gf_group, gf32->gf_slist_flex); out_free_gsf: kfree(p); return err; } static int ip_mcast_join_leave(struct sock *sk, int optname, sockptr_t optval, int optlen) { struct ip_mreqn mreq = { }; struct sockaddr_in *psin; struct group_req greq; if (optlen < sizeof(struct group_req)) return -EINVAL; if (copy_from_sockptr(&greq, optval, sizeof(greq))) return -EFAULT; psin = (struct sockaddr_in *)&greq.gr_group; if (psin->sin_family != AF_INET) return -EINVAL; mreq.imr_multiaddr = psin->sin_addr; mreq.imr_ifindex = greq.gr_interface; if (optname == MCAST_JOIN_GROUP) return ip_mc_join_group(sk, &mreq); return ip_mc_leave_group(sk, &mreq); } static int compat_ip_mcast_join_leave(struct sock *sk, int optname, sockptr_t optval, int optlen) { struct compat_group_req greq; struct ip_mreqn mreq = { }; struct sockaddr_in *psin; if (optlen < sizeof(struct compat_group_req)) return -EINVAL; if (copy_from_sockptr(&greq, optval, sizeof(greq))) return -EFAULT; psin = (struct sockaddr_in *)&greq.gr_group; if (psin->sin_family != AF_INET) return -EINVAL; mreq.imr_multiaddr = psin->sin_addr; mreq.imr_ifindex = greq.gr_interface; if (optname == MCAST_JOIN_GROUP) return ip_mc_join_group(sk, &mreq); return ip_mc_leave_group(sk, &mreq); } DEFINE_STATIC_KEY_FALSE(ip4_min_ttl); int do_ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { struct inet_sock *inet = inet_sk(sk); struct net *net = sock_net(sk); int val = 0, err; bool needs_rtnl = setsockopt_needs_rtnl(optname); switch (optname) { case IP_PKTINFO: case IP_RECVTTL: case IP_RECVOPTS: case IP_RECVTOS: case IP_RETOPTS: case IP_TOS: case IP_TTL: case IP_HDRINCL: case IP_MTU_DISCOVER: case IP_RECVERR: case IP_ROUTER_ALERT: case IP_FREEBIND: case IP_PASSSEC: case IP_TRANSPARENT: case IP_MINTTL: case IP_NODEFRAG: case IP_BIND_ADDRESS_NO_PORT: case IP_UNICAST_IF: case IP_MULTICAST_TTL: case IP_MULTICAST_ALL: case IP_MULTICAST_LOOP: case IP_RECVORIGDSTADDR: case IP_CHECKSUM: case IP_RECVFRAGSIZE: case IP_RECVERR_RFC4884: case IP_LOCAL_PORT_RANGE: if (optlen >= sizeof(int)) { if (copy_from_sockptr(&val, optval, sizeof(val))) return -EFAULT; } else if (optlen >= sizeof(char)) { unsigned char ucval; if (copy_from_sockptr(&ucval, optval, sizeof(ucval))) return -EFAULT; val = (int) ucval; } } /* If optlen==0, it is equivalent to val == 0 */ if (optname == IP_ROUTER_ALERT) return ip_ra_control(sk, val ? 1 : 0, NULL); if (ip_mroute_opt(optname)) return ip_mroute_setsockopt(sk, optname, optval, optlen); /* Handle options that can be set without locking the socket. */ switch (optname) { case IP_PKTINFO: inet_assign_bit(PKTINFO, sk, val); return 0; case IP_RECVTTL: inet_assign_bit(TTL, sk, val); return 0; case IP_RECVTOS: inet_assign_bit(TOS, sk, val); return 0; case IP_RECVOPTS: inet_assign_bit(RECVOPTS, sk, val); return 0; case IP_RETOPTS: inet_assign_bit(RETOPTS, sk, val); return 0; case IP_PASSSEC: inet_assign_bit(PASSSEC, sk, val); return 0; case IP_RECVORIGDSTADDR: inet_assign_bit(ORIGDSTADDR, sk, val); return 0; case IP_RECVFRAGSIZE: if (sk->sk_type != SOCK_RAW && sk->sk_type != SOCK_DGRAM) return -EINVAL; inet_assign_bit(RECVFRAGSIZE, sk, val); return 0; case IP_RECVERR: inet_assign_bit(RECVERR, sk, val); if (!val) skb_errqueue_purge(&sk->sk_error_queue); return 0; case IP_RECVERR_RFC4884: if (val < 0 || val > 1) return -EINVAL; inet_assign_bit(RECVERR_RFC4884, sk, val); return 0; case IP_FREEBIND: if (optlen < 1) return -EINVAL; inet_assign_bit(FREEBIND, sk, val); return 0; case IP_HDRINCL: if (sk->sk_type != SOCK_RAW) return -ENOPROTOOPT; inet_assign_bit(HDRINCL, sk, val); return 0; case IP_MULTICAST_LOOP: if (optlen < 1) return -EINVAL; inet_assign_bit(MC_LOOP, sk, val); return 0; case IP_MULTICAST_ALL: if (optlen < 1) return -EINVAL; if (val != 0 && val != 1) return -EINVAL; inet_assign_bit(MC_ALL, sk, val); return 0; case IP_TRANSPARENT: if (!!val && !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) && !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) return -EPERM; if (optlen < 1) return -EINVAL; inet_assign_bit(TRANSPARENT, sk, val); return 0; case IP_NODEFRAG: if (sk->sk_type != SOCK_RAW) return -ENOPROTOOPT; inet_assign_bit(NODEFRAG, sk, val); return 0; case IP_BIND_ADDRESS_NO_PORT: inet_assign_bit(BIND_ADDRESS_NO_PORT, sk, val); return 0; case IP_TTL: if (optlen < 1) return -EINVAL; if (val != -1 && (val < 1 || val > 255)) return -EINVAL; WRITE_ONCE(inet->uc_ttl, val); return 0; case IP_MINTTL: if (optlen < 1) return -EINVAL; if (val < 0 || val > 255) return -EINVAL; if (val) static_branch_enable(&ip4_min_ttl); WRITE_ONCE(inet->min_ttl, val); return 0; } err = 0; if (needs_rtnl) rtnl_lock(); sockopt_lock_sock(sk); switch (optname) { case IP_OPTIONS: { struct ip_options_rcu *old, *opt = NULL; if (optlen > 40) goto e_inval; err = ip_options_get(sock_net(sk), &opt, optval, optlen); if (err) break; old = rcu_dereference_protected(inet->inet_opt, lockdep_sock_is_held(sk)); if (inet_test_bit(IS_ICSK, sk)) { struct inet_connection_sock *icsk = inet_csk(sk); #if IS_ENABLED(CONFIG_IPV6) if (sk->sk_family == PF_INET || (!((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) && inet->inet_daddr != LOOPBACK4_IPV6)) { #endif if (old) icsk->icsk_ext_hdr_len -= old->opt.optlen; if (opt) icsk->icsk_ext_hdr_len += opt->opt.optlen; icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie); #if IS_ENABLED(CONFIG_IPV6) } #endif } rcu_assign_pointer(inet->inet_opt, opt); if (old) kfree_rcu(old, rcu); break; } case IP_CHECKSUM: if (val) { if (!(inet_test_bit(CHECKSUM, sk))) { inet_inc_convert_csum(sk); inet_set_bit(CHECKSUM, sk); } } else { if (inet_test_bit(CHECKSUM, sk)) { inet_dec_convert_csum(sk); inet_clear_bit(CHECKSUM, sk); } } break; case IP_TOS: /* This sets both TOS and Precedence */ __ip_sock_set_tos(sk, val); break; case IP_MTU_DISCOVER: if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT) goto e_inval; inet->pmtudisc = val; break; case IP_MULTICAST_TTL: if (sk->sk_type == SOCK_STREAM) goto e_inval; if (optlen < 1) goto e_inval; if (val == -1) val = 1; if (val < 0 || val > 255) goto e_inval; inet->mc_ttl = val; break; case IP_UNICAST_IF: { struct net_device *dev = NULL; int ifindex; int midx; if (optlen != sizeof(int)) goto e_inval; ifindex = (__force int)ntohl((__force __be32)val); if (ifindex == 0) { inet->uc_index = 0; err = 0; break; } dev = dev_get_by_index(sock_net(sk), ifindex); err = -EADDRNOTAVAIL; if (!dev) break; midx = l3mdev_master_ifindex(dev); dev_put(dev); err = -EINVAL; if (sk->sk_bound_dev_if && midx != sk->sk_bound_dev_if) break; inet->uc_index = ifindex; err = 0; break; } case IP_MULTICAST_IF: { struct ip_mreqn mreq; struct net_device *dev = NULL; int midx; if (sk->sk_type == SOCK_STREAM) goto e_inval; /* * Check the arguments are allowable */ if (optlen < sizeof(struct in_addr)) goto e_inval; err = -EFAULT; if (optlen >= sizeof(struct ip_mreqn)) { if (copy_from_sockptr(&mreq, optval, sizeof(mreq))) break; } else { memset(&mreq, 0, sizeof(mreq)); if (optlen >= sizeof(struct ip_mreq)) { if (copy_from_sockptr(&mreq, optval, sizeof(struct ip_mreq))) break; } else if (optlen >= sizeof(struct in_addr)) { if (copy_from_sockptr(&mreq.imr_address, optval, sizeof(struct in_addr))) break; } } if (!mreq.imr_ifindex) { if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) { inet->mc_index = 0; inet->mc_addr = 0; err = 0; break; } dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr); if (dev) mreq.imr_ifindex = dev->ifindex; } else dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex); err = -EADDRNOTAVAIL; if (!dev) break; midx = l3mdev_master_ifindex(dev); dev_put(dev); err = -EINVAL; if (sk->sk_bound_dev_if && mreq.imr_ifindex != sk->sk_bound_dev_if && midx != sk->sk_bound_dev_if) break; inet->mc_index = mreq.imr_ifindex; inet->mc_addr = mreq.imr_address.s_addr; err = 0; break; } case IP_ADD_MEMBERSHIP: case IP_DROP_MEMBERSHIP: { struct ip_mreqn mreq; err = -EPROTO; if (inet_test_bit(IS_ICSK, sk)) break; if (optlen < sizeof(struct ip_mreq)) goto e_inval; err = -EFAULT; if (optlen >= sizeof(struct ip_mreqn)) { if (copy_from_sockptr(&mreq, optval, sizeof(mreq))) break; } else { memset(&mreq, 0, sizeof(mreq)); if (copy_from_sockptr(&mreq, optval, sizeof(struct ip_mreq))) break; } if (optname == IP_ADD_MEMBERSHIP) err = ip_mc_join_group(sk, &mreq); else err = ip_mc_leave_group(sk, &mreq); break; } case IP_MSFILTER: { struct ip_msfilter *msf; if (optlen < IP_MSFILTER_SIZE(0)) goto e_inval; if (optlen > READ_ONCE(sysctl_optmem_max)) { err = -ENOBUFS; break; } msf = memdup_sockptr(optval, optlen); if (IS_ERR(msf)) { err = PTR_ERR(msf); break; } /* numsrc >= (1G-4) overflow in 32 bits */ if (msf->imsf_numsrc >= 0x3ffffffcU || msf->imsf_numsrc > READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) { kfree(msf); err = -ENOBUFS; break; } if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) { kfree(msf); err = -EINVAL; break; } err = ip_mc_msfilter(sk, msf, 0); kfree(msf); break; } case IP_BLOCK_SOURCE: case IP_UNBLOCK_SOURCE: case IP_ADD_SOURCE_MEMBERSHIP: case IP_DROP_SOURCE_MEMBERSHIP: { struct ip_mreq_source mreqs; int omode, add; if (optlen != sizeof(struct ip_mreq_source)) goto e_inval; if (copy_from_sockptr(&mreqs, optval, sizeof(mreqs))) { err = -EFAULT; break; } if (optname == IP_BLOCK_SOURCE) { omode = MCAST_EXCLUDE; add = 1; } else if (optname == IP_UNBLOCK_SOURCE) { omode = MCAST_EXCLUDE; add = 0; } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) { struct ip_mreqn mreq; mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr; mreq.imr_address.s_addr = mreqs.imr_interface; mreq.imr_ifindex = 0; err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE); if (err && err != -EADDRINUSE) break; omode = MCAST_INCLUDE; add = 1; } else /* IP_DROP_SOURCE_MEMBERSHIP */ { omode = MCAST_INCLUDE; add = 0; } err = ip_mc_source(add, omode, sk, &mreqs, 0); break; } case MCAST_JOIN_GROUP: case MCAST_LEAVE_GROUP: if (in_compat_syscall()) err = compat_ip_mcast_join_leave(sk, optname, optval, optlen); else err = ip_mcast_join_leave(sk, optname, optval, optlen); break; case MCAST_JOIN_SOURCE_GROUP: case MCAST_LEAVE_SOURCE_GROUP: case MCAST_BLOCK_SOURCE: case MCAST_UNBLOCK_SOURCE: err = do_mcast_group_source(sk, optname, optval, optlen); break; case MCAST_MSFILTER: if (in_compat_syscall()) err = compat_ip_set_mcast_msfilter(sk, optval, optlen); else err = ip_set_mcast_msfilter(sk, optval, optlen); break; case IP_IPSEC_POLICY: case IP_XFRM_POLICY: err = -EPERM; if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) break; err = xfrm_user_policy(sk, optname, optval, optlen); break; case IP_LOCAL_PORT_RANGE: { const __u16 lo = val; const __u16 hi = val >> 16; if (optlen != sizeof(__u32)) goto e_inval; if (lo != 0 && hi != 0 && lo > hi) goto e_inval; inet->local_port_range.lo = lo; inet->local_port_range.hi = hi; break; } default: err = -ENOPROTOOPT; break; } sockopt_release_sock(sk); if (needs_rtnl) rtnl_unlock(); return err; e_inval: sockopt_release_sock(sk); if (needs_rtnl) rtnl_unlock(); return -EINVAL; } /** * ipv4_pktinfo_prepare - transfer some info from rtable to skb * @sk: socket * @skb: buffer * * To support IP_CMSG_PKTINFO option, we store rt_iif and specific * destination in skb->cb[] before dst drop. * This way, receiver doesn't make cache line misses to read rtable. */ void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb) { struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb); bool prepare = inet_test_bit(PKTINFO, sk) || ipv6_sk_rxinfo(sk); if (prepare && skb_rtable(skb)) { /* skb->cb is overloaded: prior to this point it is IP{6}CB * which has interface index (iif) as the first member of the * underlying inet{6}_skb_parm struct. This code then overlays * PKTINFO_SKB_CB and in_pktinfo also has iif as the first * element so the iif is picked up from the prior IPCB. If iif * is the loopback interface, then return the sending interface * (e.g., process binds socket to eth0 for Tx which is * redirected to loopback in the rtable/dst). */ struct rtable *rt = skb_rtable(skb); bool l3slave = ipv4_l3mdev_skb(IPCB(skb)->flags); if (pktinfo->ipi_ifindex == LOOPBACK_IFINDEX) pktinfo->ipi_ifindex = inet_iif(skb); else if (l3slave && rt && rt->rt_iif) pktinfo->ipi_ifindex = rt->rt_iif; pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb); } else { pktinfo->ipi_ifindex = 0; pktinfo->ipi_spec_dst.s_addr = 0; } skb_dst_drop(skb); } int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { int err; if (level != SOL_IP) return -ENOPROTOOPT; err = do_ip_setsockopt(sk, level, optname, optval, optlen); #if IS_ENABLED(CONFIG_BPFILTER_UMH) if (optname >= BPFILTER_IPT_SO_SET_REPLACE && optname < BPFILTER_IPT_SET_MAX) err = bpfilter_ip_set_sockopt(sk, optname, optval, optlen); #endif #ifdef CONFIG_NETFILTER /* we need to exclude all possible ENOPROTOOPTs except default case */ if (err == -ENOPROTOOPT && optname != IP_HDRINCL && optname != IP_IPSEC_POLICY && optname != IP_XFRM_POLICY && !ip_mroute_opt(optname)) err = nf_setsockopt(sk, PF_INET, optname, optval, optlen); #endif return err; } EXPORT_SYMBOL(ip_setsockopt); /* * Get the options. Note for future reference. The GET of IP options gets * the _received_ ones. The set sets the _sent_ ones. */ static bool getsockopt_needs_rtnl(int optname) { switch (optname) { case IP_MSFILTER: case MCAST_MSFILTER: return true; } return false; } static int ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval, sockptr_t optlen, int len) { const int size0 = offsetof(struct group_filter, gf_slist_flex); struct group_filter gsf; int num, gsf_size; int err; if (len < size0) return -EINVAL; if (copy_from_sockptr(&gsf, optval, size0)) return -EFAULT; num = gsf.gf_numsrc; err = ip_mc_gsfget(sk, &gsf, optval, offsetof(struct group_filter, gf_slist_flex)); if (err) return err; if (gsf.gf_numsrc < num) num = gsf.gf_numsrc; gsf_size = GROUP_FILTER_SIZE(num); if (copy_to_sockptr(optlen, &gsf_size, sizeof(int)) || copy_to_sockptr(optval, &gsf, size0)) return -EFAULT; return 0; } static int compat_ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval, sockptr_t optlen, int len) { const int size0 = offsetof(struct compat_group_filter, gf_slist_flex); struct compat_group_filter gf32; struct group_filter gf; int num; int err; if (len < size0) return -EINVAL; if (copy_from_sockptr(&gf32, optval, size0)) return -EFAULT; gf.gf_interface = gf32.gf_interface; gf.gf_fmode = gf32.gf_fmode; num = gf.gf_numsrc = gf32.gf_numsrc; gf.gf_group = gf32.gf_group; err = ip_mc_gsfget(sk, &gf, optval, offsetof(struct compat_group_filter, gf_slist_flex)); if (err) return err; if (gf.gf_numsrc < num) num = gf.gf_numsrc; len = GROUP_FILTER_SIZE(num) - (sizeof(gf) - sizeof(gf32)); if (copy_to_sockptr(optlen, &len, sizeof(int)) || copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode), &gf.gf_fmode, sizeof(gf.gf_fmode)) || copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc), &gf.gf_numsrc, sizeof(gf.gf_numsrc))) return -EFAULT; return 0; } int do_ip_getsockopt(struct sock *sk, int level, int optname, sockptr_t optval, sockptr_t optlen) { struct inet_sock *inet = inet_sk(sk); bool needs_rtnl = getsockopt_needs_rtnl(optname); int val, err = 0; int len; if (level != SOL_IP) return -EOPNOTSUPP; if (ip_mroute_opt(optname)) return ip_mroute_getsockopt(sk, optname, optval, optlen); if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; if (len < 0) return -EINVAL; /* Handle options that can be read without locking the socket. */ switch (optname) { case IP_PKTINFO: val = inet_test_bit(PKTINFO, sk); goto copyval; case IP_RECVTTL: val = inet_test_bit(TTL, sk); goto copyval; case IP_RECVTOS: val = inet_test_bit(TOS, sk); goto copyval; case IP_RECVOPTS: val = inet_test_bit(RECVOPTS, sk); goto copyval; case IP_RETOPTS: val = inet_test_bit(RETOPTS, sk); goto copyval; case IP_PASSSEC: val = inet_test_bit(PASSSEC, sk); goto copyval; case IP_RECVORIGDSTADDR: val = inet_test_bit(ORIGDSTADDR, sk); goto copyval; case IP_CHECKSUM: val = inet_test_bit(CHECKSUM, sk); goto copyval; case IP_RECVFRAGSIZE: val = inet_test_bit(RECVFRAGSIZE, sk); goto copyval; case IP_RECVERR: val = inet_test_bit(RECVERR, sk); goto copyval; case IP_RECVERR_RFC4884: val = inet_test_bit(RECVERR_RFC4884, sk); goto copyval; case IP_FREEBIND: val = inet_test_bit(FREEBIND, sk); goto copyval; case IP_HDRINCL: val = inet_test_bit(HDRINCL, sk); goto copyval; case IP_MULTICAST_LOOP: val = inet_test_bit(MC_LOOP, sk); goto copyval; case IP_MULTICAST_ALL: val = inet_test_bit(MC_ALL, sk); goto copyval; case IP_TRANSPARENT: val = inet_test_bit(TRANSPARENT, sk); goto copyval; case IP_NODEFRAG: val = inet_test_bit(NODEFRAG, sk); goto copyval; case IP_BIND_ADDRESS_NO_PORT: val = inet_test_bit(BIND_ADDRESS_NO_PORT, sk); goto copyval; case IP_TTL: val = READ_ONCE(inet->uc_ttl); if (val < 0) val = READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_default_ttl); goto copyval; case IP_MINTTL: val = READ_ONCE(inet->min_ttl); goto copyval; } if (needs_rtnl) rtnl_lock(); sockopt_lock_sock(sk); switch (optname) { case IP_OPTIONS: { unsigned char optbuf[sizeof(struct ip_options)+40]; struct ip_options *opt = (struct ip_options *)optbuf; struct ip_options_rcu *inet_opt; inet_opt = rcu_dereference_protected(inet->inet_opt, lockdep_sock_is_held(sk)); opt->optlen = 0; if (inet_opt) memcpy(optbuf, &inet_opt->opt, sizeof(struct ip_options) + inet_opt->opt.optlen); sockopt_release_sock(sk); if (opt->optlen == 0) { len = 0; return copy_to_sockptr(optlen, &len, sizeof(int)); } ip_options_undo(opt); len = min_t(unsigned int, len, opt->optlen); if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, opt->__data, len)) return -EFAULT; return 0; } case IP_TOS: val = inet->tos; break; case IP_MTU_DISCOVER: val = inet->pmtudisc; break; case IP_MTU: { struct dst_entry *dst; val = 0; dst = sk_dst_get(sk); if (dst) { val = dst_mtu(dst); dst_release(dst); } if (!val) { sockopt_release_sock(sk); return -ENOTCONN; } break; } case IP_MULTICAST_TTL: val = inet->mc_ttl; break; case IP_UNICAST_IF: val = (__force int)htonl((__u32) inet->uc_index); break; case IP_MULTICAST_IF: { struct in_addr addr; len = min_t(unsigned int, len, sizeof(struct in_addr)); addr.s_addr = inet->mc_addr; sockopt_release_sock(sk); if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, &addr, len)) return -EFAULT; return 0; } case IP_MSFILTER: { struct ip_msfilter msf; if (len < IP_MSFILTER_SIZE(0)) { err = -EINVAL; goto out; } if (copy_from_sockptr(&msf, optval, IP_MSFILTER_SIZE(0))) { err = -EFAULT; goto out; } err = ip_mc_msfget(sk, &msf, optval, optlen); goto out; } case MCAST_MSFILTER: if (in_compat_syscall()) err = compat_ip_get_mcast_msfilter(sk, optval, optlen, len); else err = ip_get_mcast_msfilter(sk, optval, optlen, len); goto out; case IP_PKTOPTIONS: { struct msghdr msg; sockopt_release_sock(sk); if (sk->sk_type != SOCK_STREAM) return -ENOPROTOOPT; if (optval.is_kernel) { msg.msg_control_is_user = false; msg.msg_control = optval.kernel; } else { msg.msg_control_is_user = true; msg.msg_control_user = optval.user; } msg.msg_controllen = len; msg.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0; if (inet_test_bit(PKTINFO, sk)) { struct in_pktinfo info; info.ipi_addr.s_addr = inet->inet_rcv_saddr; info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr; info.ipi_ifindex = inet->mc_index; put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info); } if (inet_test_bit(TTL, sk)) { int hlim = inet->mc_ttl; put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim); } if (inet_test_bit(TOS, sk)) { int tos = inet->rcv_tos; put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos); } len -= msg.msg_controllen; return copy_to_sockptr(optlen, &len, sizeof(int)); } case IP_LOCAL_PORT_RANGE: val = inet->local_port_range.hi << 16 | inet->local_port_range.lo; break; case IP_PROTOCOL: val = inet_sk(sk)->inet_num; break; default: sockopt_release_sock(sk); return -ENOPROTOOPT; } sockopt_release_sock(sk); copyval: if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) { unsigned char ucval = (unsigned char)val; len = 1; if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, &ucval, 1)) return -EFAULT; } else { len = min_t(unsigned int, sizeof(int), len); if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, &val, len)) return -EFAULT; } return 0; out: sockopt_release_sock(sk); if (needs_rtnl) rtnl_unlock(); return err; } int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { int err; err = do_ip_getsockopt(sk, level, optname, USER_SOCKPTR(optval), USER_SOCKPTR(optlen)); #if IS_ENABLED(CONFIG_BPFILTER_UMH) if (optname >= BPFILTER_IPT_SO_GET_INFO && optname < BPFILTER_IPT_GET_MAX) err = bpfilter_ip_get_sockopt(sk, optname, optval, optlen); #endif #ifdef CONFIG_NETFILTER /* we need to exclude all possible ENOPROTOOPTs except default case */ if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS && !ip_mroute_opt(optname)) { int len; if (get_user(len, optlen)) return -EFAULT; err = nf_getsockopt(sk, PF_INET, optname, optval, &len); if (err >= 0) err = put_user(len, optlen); return err; } #endif return err; } EXPORT_SYMBOL(ip_getsockopt);
linux-master
net/ipv4/ip_sockglue.c
// SPDX-License-Identifier: GPL-2.0 /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * The options processing module for ip.c * * Authors: A.N.Kuznetsov * */ #define pr_fmt(fmt) "IPv4: " fmt #include <linux/capability.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/types.h> #include <linux/uaccess.h> #include <asm/unaligned.h> #include <linux/skbuff.h> #include <linux/ip.h> #include <linux/icmp.h> #include <linux/netdevice.h> #include <linux/rtnetlink.h> #include <net/sock.h> #include <net/ip.h> #include <net/icmp.h> #include <net/route.h> #include <net/cipso_ipv4.h> #include <net/ip_fib.h> /* * Write options to IP header, record destination address to * source route option, address of outgoing interface * (we should already know it, so that this function is allowed be * called only after routing decision) and timestamp, * if we originate this datagram. * * daddr is real destination address, next hop is recorded in IP header. * saddr is address of outgoing interface. */ void ip_options_build(struct sk_buff *skb, struct ip_options *opt, __be32 daddr, struct rtable *rt) { unsigned char *iph = skb_network_header(skb); memcpy(&(IPCB(skb)->opt), opt, sizeof(struct ip_options)); memcpy(iph + sizeof(struct iphdr), opt->__data, opt->optlen); opt = &(IPCB(skb)->opt); if (opt->srr) memcpy(iph + opt->srr + iph[opt->srr + 1] - 4, &daddr, 4); if (opt->rr_needaddr) ip_rt_get_source(iph + opt->rr + iph[opt->rr + 2] - 5, skb, rt); if (opt->ts_needaddr) ip_rt_get_source(iph + opt->ts + iph[opt->ts + 2] - 9, skb, rt); if (opt->ts_needtime) { __be32 midtime; midtime = inet_current_timestamp(); memcpy(iph + opt->ts + iph[opt->ts + 2] - 5, &midtime, 4); } } /* * Provided (sopt, skb) points to received options, * build in dopt compiled option set appropriate for answering. * i.e. invert SRR option, copy anothers, * and grab room in RR/TS options. * * NOTE: dopt cannot point to skb. */ int __ip_options_echo(struct net *net, struct ip_options *dopt, struct sk_buff *skb, const struct ip_options *sopt) { unsigned char *sptr, *dptr; int soffset, doffset; int optlen; memset(dopt, 0, sizeof(struct ip_options)); if (sopt->optlen == 0) return 0; sptr = skb_network_header(skb); dptr = dopt->__data; if (sopt->rr) { optlen = sptr[sopt->rr+1]; soffset = sptr[sopt->rr+2]; dopt->rr = dopt->optlen + sizeof(struct iphdr); memcpy(dptr, sptr+sopt->rr, optlen); if (sopt->rr_needaddr && soffset <= optlen) { if (soffset + 3 > optlen) return -EINVAL; dptr[2] = soffset + 4; dopt->rr_needaddr = 1; } dptr += optlen; dopt->optlen += optlen; } if (sopt->ts) { optlen = sptr[sopt->ts+1]; soffset = sptr[sopt->ts+2]; dopt->ts = dopt->optlen + sizeof(struct iphdr); memcpy(dptr, sptr+sopt->ts, optlen); if (soffset <= optlen) { if (sopt->ts_needaddr) { if (soffset + 3 > optlen) return -EINVAL; dopt->ts_needaddr = 1; soffset += 4; } if (sopt->ts_needtime) { if (soffset + 3 > optlen) return -EINVAL; if ((dptr[3]&0xF) != IPOPT_TS_PRESPEC) { dopt->ts_needtime = 1; soffset += 4; } else { dopt->ts_needtime = 0; if (soffset + 7 <= optlen) { __be32 addr; memcpy(&addr, dptr+soffset-1, 4); if (inet_addr_type(net, addr) != RTN_UNICAST) { dopt->ts_needtime = 1; soffset += 8; } } } } dptr[2] = soffset; } dptr += optlen; dopt->optlen += optlen; } if (sopt->srr) { unsigned char *start = sptr+sopt->srr; __be32 faddr; optlen = start[1]; soffset = start[2]; doffset = 0; if (soffset > optlen) soffset = optlen + 1; soffset -= 4; if (soffset > 3) { memcpy(&faddr, &start[soffset-1], 4); for (soffset -= 4, doffset = 4; soffset > 3; soffset -= 4, doffset += 4) memcpy(&dptr[doffset-1], &start[soffset-1], 4); /* * RFC1812 requires to fix illegal source routes. */ if (memcmp(&ip_hdr(skb)->saddr, &start[soffset + 3], 4) == 0) doffset -= 4; } if (doffset > 3) { dopt->faddr = faddr; dptr[0] = start[0]; dptr[1] = doffset+3; dptr[2] = 4; dptr += doffset+3; dopt->srr = dopt->optlen + sizeof(struct iphdr); dopt->optlen += doffset+3; dopt->is_strictroute = sopt->is_strictroute; } } if (sopt->cipso) { optlen = sptr[sopt->cipso+1]; dopt->cipso = dopt->optlen+sizeof(struct iphdr); memcpy(dptr, sptr+sopt->cipso, optlen); dptr += optlen; dopt->optlen += optlen; } while (dopt->optlen & 3) { *dptr++ = IPOPT_END; dopt->optlen++; } return 0; } /* * Options "fragmenting", just fill options not * allowed in fragments with NOOPs. * Simple and stupid 8), but the most efficient way. */ void ip_options_fragment(struct sk_buff *skb) { unsigned char *optptr = skb_network_header(skb) + sizeof(struct iphdr); struct ip_options *opt = &(IPCB(skb)->opt); int l = opt->optlen; int optlen; while (l > 0) { switch (*optptr) { case IPOPT_END: return; case IPOPT_NOOP: l--; optptr++; continue; } optlen = optptr[1]; if (optlen < 2 || optlen > l) return; if (!IPOPT_COPIED(*optptr)) memset(optptr, IPOPT_NOOP, optlen); l -= optlen; optptr += optlen; } opt->ts = 0; opt->rr = 0; opt->rr_needaddr = 0; opt->ts_needaddr = 0; opt->ts_needtime = 0; } /* helper used by ip_options_compile() to call fib_compute_spec_dst() * at most one time. */ static void spec_dst_fill(__be32 *spec_dst, struct sk_buff *skb) { if (*spec_dst == htonl(INADDR_ANY)) *spec_dst = fib_compute_spec_dst(skb); } /* * Verify options and fill pointers in struct options. * Caller should clear *opt, and set opt->data. * If opt == NULL, then skb->data should point to IP header. */ int __ip_options_compile(struct net *net, struct ip_options *opt, struct sk_buff *skb, __be32 *info) { __be32 spec_dst = htonl(INADDR_ANY); unsigned char *pp_ptr = NULL; struct rtable *rt = NULL; unsigned char *optptr; unsigned char *iph; int optlen, l; if (skb) { rt = skb_rtable(skb); optptr = (unsigned char *)&(ip_hdr(skb)[1]); } else optptr = opt->__data; iph = optptr - sizeof(struct iphdr); for (l = opt->optlen; l > 0; ) { switch (*optptr) { case IPOPT_END: for (optptr++, l--; l > 0; optptr++, l--) { if (*optptr != IPOPT_END) { *optptr = IPOPT_END; opt->is_changed = 1; } } goto eol; case IPOPT_NOOP: l--; optptr++; continue; } if (unlikely(l < 2)) { pp_ptr = optptr; goto error; } optlen = optptr[1]; if (optlen < 2 || optlen > l) { pp_ptr = optptr; goto error; } switch (*optptr) { case IPOPT_SSRR: case IPOPT_LSRR: if (optlen < 3) { pp_ptr = optptr + 1; goto error; } if (optptr[2] < 4) { pp_ptr = optptr + 2; goto error; } /* NB: cf RFC-1812 5.2.4.1 */ if (opt->srr) { pp_ptr = optptr; goto error; } if (!skb) { if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3)) { pp_ptr = optptr + 1; goto error; } memcpy(&opt->faddr, &optptr[3], 4); if (optlen > 7) memmove(&optptr[3], &optptr[7], optlen-7); } opt->is_strictroute = (optptr[0] == IPOPT_SSRR); opt->srr = optptr - iph; break; case IPOPT_RR: if (opt->rr) { pp_ptr = optptr; goto error; } if (optlen < 3) { pp_ptr = optptr + 1; goto error; } if (optptr[2] < 4) { pp_ptr = optptr + 2; goto error; } if (optptr[2] <= optlen) { if (optptr[2]+3 > optlen) { pp_ptr = optptr + 2; goto error; } if (rt) { spec_dst_fill(&spec_dst, skb); memcpy(&optptr[optptr[2]-1], &spec_dst, 4); opt->is_changed = 1; } optptr[2] += 4; opt->rr_needaddr = 1; } opt->rr = optptr - iph; break; case IPOPT_TIMESTAMP: if (opt->ts) { pp_ptr = optptr; goto error; } if (optlen < 4) { pp_ptr = optptr + 1; goto error; } if (optptr[2] < 5) { pp_ptr = optptr + 2; goto error; } if (optptr[2] <= optlen) { unsigned char *timeptr = NULL; if (optptr[2]+3 > optlen) { pp_ptr = optptr + 2; goto error; } switch (optptr[3]&0xF) { case IPOPT_TS_TSONLY: if (skb) timeptr = &optptr[optptr[2]-1]; opt->ts_needtime = 1; optptr[2] += 4; break; case IPOPT_TS_TSANDADDR: if (optptr[2]+7 > optlen) { pp_ptr = optptr + 2; goto error; } if (rt) { spec_dst_fill(&spec_dst, skb); memcpy(&optptr[optptr[2]-1], &spec_dst, 4); timeptr = &optptr[optptr[2]+3]; } opt->ts_needaddr = 1; opt->ts_needtime = 1; optptr[2] += 8; break; case IPOPT_TS_PRESPEC: if (optptr[2]+7 > optlen) { pp_ptr = optptr + 2; goto error; } { __be32 addr; memcpy(&addr, &optptr[optptr[2]-1], 4); if (inet_addr_type(net, addr) == RTN_UNICAST) break; if (skb) timeptr = &optptr[optptr[2]+3]; } opt->ts_needtime = 1; optptr[2] += 8; break; default: if (!skb && !ns_capable(net->user_ns, CAP_NET_RAW)) { pp_ptr = optptr + 3; goto error; } break; } if (timeptr) { __be32 midtime; midtime = inet_current_timestamp(); memcpy(timeptr, &midtime, 4); opt->is_changed = 1; } } else if ((optptr[3]&0xF) != IPOPT_TS_PRESPEC) { unsigned int overflow = optptr[3]>>4; if (overflow == 15) { pp_ptr = optptr + 3; goto error; } if (skb) { optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4); opt->is_changed = 1; } } opt->ts = optptr - iph; break; case IPOPT_RA: if (optlen < 4) { pp_ptr = optptr + 1; goto error; } if (optptr[2] == 0 && optptr[3] == 0) opt->router_alert = optptr - iph; break; case IPOPT_CIPSO: if ((!skb && !ns_capable(net->user_ns, CAP_NET_RAW)) || opt->cipso) { pp_ptr = optptr; goto error; } opt->cipso = optptr - iph; if (cipso_v4_validate(skb, &optptr)) { pp_ptr = optptr; goto error; } break; case IPOPT_SEC: case IPOPT_SID: default: if (!skb && !ns_capable(net->user_ns, CAP_NET_RAW)) { pp_ptr = optptr; goto error; } break; } l -= optlen; optptr += optlen; } eol: if (!pp_ptr) return 0; error: if (info) *info = htonl((pp_ptr-iph)<<24); return -EINVAL; } EXPORT_SYMBOL(__ip_options_compile); int ip_options_compile(struct net *net, struct ip_options *opt, struct sk_buff *skb) { int ret; __be32 info; ret = __ip_options_compile(net, opt, skb, &info); if (ret != 0 && skb) icmp_send(skb, ICMP_PARAMETERPROB, 0, info); return ret; } EXPORT_SYMBOL(ip_options_compile); /* * Undo all the changes done by ip_options_compile(). */ void ip_options_undo(struct ip_options *opt) { if (opt->srr) { unsigned char *optptr = opt->__data + opt->srr - sizeof(struct iphdr); memmove(optptr + 7, optptr + 3, optptr[1] - 7); memcpy(optptr + 3, &opt->faddr, 4); } if (opt->rr_needaddr) { unsigned char *optptr = opt->__data + opt->rr - sizeof(struct iphdr); optptr[2] -= 4; memset(&optptr[optptr[2] - 1], 0, 4); } if (opt->ts) { unsigned char *optptr = opt->__data + opt->ts - sizeof(struct iphdr); if (opt->ts_needtime) { optptr[2] -= 4; memset(&optptr[optptr[2] - 1], 0, 4); if ((optptr[3] & 0xF) == IPOPT_TS_PRESPEC) optptr[2] -= 4; } if (opt->ts_needaddr) { optptr[2] -= 4; memset(&optptr[optptr[2] - 1], 0, 4); } } } int ip_options_get(struct net *net, struct ip_options_rcu **optp, sockptr_t data, int optlen) { struct ip_options_rcu *opt; opt = kzalloc(sizeof(struct ip_options_rcu) + ((optlen + 3) & ~3), GFP_KERNEL); if (!opt) return -ENOMEM; if (optlen && copy_from_sockptr(opt->opt.__data, data, optlen)) { kfree(opt); return -EFAULT; } while (optlen & 3) opt->opt.__data[optlen++] = IPOPT_END; opt->opt.optlen = optlen; if (optlen && ip_options_compile(net, &opt->opt, NULL)) { kfree(opt); return -EINVAL; } kfree(*optp); *optp = opt; return 0; } void ip_forward_options(struct sk_buff *skb) { struct ip_options *opt = &(IPCB(skb)->opt); unsigned char *optptr; struct rtable *rt = skb_rtable(skb); unsigned char *raw = skb_network_header(skb); if (opt->rr_needaddr) { optptr = (unsigned char *)raw + opt->rr; ip_rt_get_source(&optptr[optptr[2]-5], skb, rt); opt->is_changed = 1; } if (opt->srr_is_hit) { int srrptr, srrspace; optptr = raw + opt->srr; for ( srrptr = optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4 ) { if (srrptr + 3 > srrspace) break; if (memcmp(&opt->nexthop, &optptr[srrptr-1], 4) == 0) break; } if (srrptr + 3 <= srrspace) { opt->is_changed = 1; ip_hdr(skb)->daddr = opt->nexthop; ip_rt_get_source(&optptr[srrptr-1], skb, rt); optptr[2] = srrptr+4; } else { net_crit_ratelimited("%s(): Argh! Destination lost!\n", __func__); } if (opt->ts_needaddr) { optptr = raw + opt->ts; ip_rt_get_source(&optptr[optptr[2]-9], skb, rt); opt->is_changed = 1; } } if (opt->is_changed) { opt->is_changed = 0; ip_send_check(ip_hdr(skb)); } } int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev) { struct ip_options *opt = &(IPCB(skb)->opt); int srrspace, srrptr; __be32 nexthop; struct iphdr *iph = ip_hdr(skb); unsigned char *optptr = skb_network_header(skb) + opt->srr; struct rtable *rt = skb_rtable(skb); struct rtable *rt2; unsigned long orefdst; int err; if (!rt) return 0; if (skb->pkt_type != PACKET_HOST) return -EINVAL; if (rt->rt_type == RTN_UNICAST) { if (!opt->is_strictroute) return 0; icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl(16<<24)); return -EINVAL; } if (rt->rt_type != RTN_LOCAL) return -EINVAL; for (srrptr = optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4) { if (srrptr + 3 > srrspace) { icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((opt->srr+2)<<24)); return -EINVAL; } memcpy(&nexthop, &optptr[srrptr-1], 4); orefdst = skb->_skb_refdst; skb_dst_set(skb, NULL); err = ip_route_input(skb, nexthop, iph->saddr, iph->tos, dev); rt2 = skb_rtable(skb); if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) { skb_dst_drop(skb); skb->_skb_refdst = orefdst; return -EINVAL; } refdst_drop(orefdst); if (rt2->rt_type != RTN_LOCAL) break; /* Superfast 8) loopback forward */ iph->daddr = nexthop; opt->is_changed = 1; } if (srrptr <= srrspace) { opt->srr_is_hit = 1; opt->nexthop = nexthop; opt->is_changed = 1; } return 0; } EXPORT_SYMBOL(ip_options_rcv_srr);
linux-master
net/ipv4/ip_options.c
// SPDX-License-Identifier: GPL-2.0-only /* * IPV4 GSO/GRO offload support * Linux INET implementation * * Copyright (C) 2016 secunet Security Networks AG * Author: Steffen Klassert <[email protected]> * * ESP GRO support */ #include <linux/skbuff.h> #include <linux/init.h> #include <net/protocol.h> #include <crypto/aead.h> #include <crypto/authenc.h> #include <linux/err.h> #include <linux/module.h> #include <net/gro.h> #include <net/gso.h> #include <net/ip.h> #include <net/xfrm.h> #include <net/esp.h> #include <linux/scatterlist.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <net/udp.h> static struct sk_buff *esp4_gro_receive(struct list_head *head, struct sk_buff *skb) { int offset = skb_gro_offset(skb); struct xfrm_offload *xo; struct xfrm_state *x; __be32 seq; __be32 spi; if (!pskb_pull(skb, offset)) return NULL; if (xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq) != 0) goto out; xo = xfrm_offload(skb); if (!xo || !(xo->flags & CRYPTO_DONE)) { struct sec_path *sp = secpath_set(skb); if (!sp) goto out; if (sp->len == XFRM_MAX_DEPTH) goto out_reset; x = xfrm_state_lookup(dev_net(skb->dev), skb->mark, (xfrm_address_t *)&ip_hdr(skb)->daddr, spi, IPPROTO_ESP, AF_INET); if (!x) goto out_reset; skb->mark = xfrm_smark_get(skb->mark, x); sp->xvec[sp->len++] = x; sp->olen++; xo = xfrm_offload(skb); if (!xo) goto out_reset; } xo->flags |= XFRM_GRO; XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; XFRM_SPI_SKB_CB(skb)->family = AF_INET; XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); XFRM_SPI_SKB_CB(skb)->seq = seq; /* We don't need to handle errors from xfrm_input, it does all * the error handling and frees the resources on error. */ xfrm_input(skb, IPPROTO_ESP, spi, -2); return ERR_PTR(-EINPROGRESS); out_reset: secpath_reset(skb); out: skb_push(skb, offset); NAPI_GRO_CB(skb)->same_flow = 0; NAPI_GRO_CB(skb)->flush = 1; return NULL; } static void esp4_gso_encap(struct xfrm_state *x, struct sk_buff *skb) { struct ip_esp_hdr *esph; struct iphdr *iph = ip_hdr(skb); struct xfrm_offload *xo = xfrm_offload(skb); int proto = iph->protocol; skb_push(skb, -skb_network_offset(skb)); esph = ip_esp_hdr(skb); *skb_mac_header(skb) = IPPROTO_ESP; esph->spi = x->id.spi; esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); xo->proto = proto; } static struct sk_buff *xfrm4_tunnel_gso_segment(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) { __be16 type = x->inner_mode.family == AF_INET6 ? htons(ETH_P_IPV6) : htons(ETH_P_IP); return skb_eth_gso_segment(skb, features, type); } static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) { const struct net_offload *ops; struct sk_buff *segs = ERR_PTR(-EINVAL); struct xfrm_offload *xo = xfrm_offload(skb); skb->transport_header += x->props.header_len; ops = rcu_dereference(inet_offloads[xo->proto]); if (likely(ops && ops->callbacks.gso_segment)) segs = ops->callbacks.gso_segment(skb, features); return segs; } static struct sk_buff *xfrm4_beet_gso_segment(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) { struct xfrm_offload *xo = xfrm_offload(skb); struct sk_buff *segs = ERR_PTR(-EINVAL); const struct net_offload *ops; u8 proto = xo->proto; skb->transport_header += x->props.header_len; if (x->sel.family != AF_INET6) { if (proto == IPPROTO_BEETPH) { struct ip_beet_phdr *ph = (struct ip_beet_phdr *)skb->data; skb->transport_header += ph->hdrlen * 8; proto = ph->nexthdr; } else { skb->transport_header -= IPV4_BEET_PHMAXLEN; } } else { __be16 frag; skb->transport_header += ipv6_skip_exthdr(skb, 0, &proto, &frag); if (proto == IPPROTO_TCP) skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4; } if (proto == IPPROTO_IPV6) skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4; __skb_pull(skb, skb_transport_offset(skb)); ops = rcu_dereference(inet_offloads[proto]); if (likely(ops && ops->callbacks.gso_segment)) segs = ops->callbacks.gso_segment(skb, features); return segs; } static struct sk_buff *xfrm4_outer_mode_gso_segment(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) { switch (x->outer_mode.encap) { case XFRM_MODE_TUNNEL: return xfrm4_tunnel_gso_segment(x, skb, features); case XFRM_MODE_TRANSPORT: return xfrm4_transport_gso_segment(x, skb, features); case XFRM_MODE_BEET: return xfrm4_beet_gso_segment(x, skb, features); } return ERR_PTR(-EOPNOTSUPP); } static struct sk_buff *esp4_gso_segment(struct sk_buff *skb, netdev_features_t features) { struct xfrm_state *x; struct ip_esp_hdr *esph; struct crypto_aead *aead; netdev_features_t esp_features = features; struct xfrm_offload *xo = xfrm_offload(skb); struct sec_path *sp; if (!xo) return ERR_PTR(-EINVAL); if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP)) return ERR_PTR(-EINVAL); sp = skb_sec_path(skb); x = sp->xvec[sp->len - 1]; aead = x->data; esph = ip_esp_hdr(skb); if (esph->spi != x->id.spi) return ERR_PTR(-EINVAL); if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) return ERR_PTR(-EINVAL); __skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)); skb->encap_hdr_csum = 1; if ((!(skb->dev->gso_partial_features & NETIF_F_HW_ESP) && !(features & NETIF_F_HW_ESP)) || x->xso.dev != skb->dev) esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK | NETIF_F_SCTP_CRC); else if (!(features & NETIF_F_HW_ESP_TX_CSUM) && !(skb->dev->gso_partial_features & NETIF_F_HW_ESP_TX_CSUM)) esp_features = features & ~(NETIF_F_CSUM_MASK | NETIF_F_SCTP_CRC); xo->flags |= XFRM_GSO_SEGMENT; return xfrm4_outer_mode_gso_segment(x, skb, esp_features); } static int esp_input_tail(struct xfrm_state *x, struct sk_buff *skb) { struct crypto_aead *aead = x->data; struct xfrm_offload *xo = xfrm_offload(skb); if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead))) return -EINVAL; if (!(xo->flags & CRYPTO_DONE)) skb->ip_summed = CHECKSUM_NONE; return esp_input_done2(skb, 0); } static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) { int err; int alen; int blksize; struct xfrm_offload *xo; struct ip_esp_hdr *esph; struct crypto_aead *aead; struct esp_info esp; bool hw_offload = true; __u32 seq; esp.inplace = true; xo = xfrm_offload(skb); if (!xo) return -EINVAL; if ((!(features & NETIF_F_HW_ESP) && !(skb->dev->gso_partial_features & NETIF_F_HW_ESP)) || x->xso.dev != skb->dev) { xo->flags |= CRYPTO_FALLBACK; hw_offload = false; } esp.proto = xo->proto; /* skb is pure payload to encrypt */ aead = x->data; alen = crypto_aead_authsize(aead); esp.tfclen = 0; /* XXX: Add support for tfc padding here. */ blksize = ALIGN(crypto_aead_blocksize(aead), 4); esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); esp.plen = esp.clen - skb->len - esp.tfclen; esp.tailen = esp.tfclen + esp.plen + alen; esp.esph = ip_esp_hdr(skb); if (!hw_offload || !skb_is_gso(skb)) { esp.nfrags = esp_output_head(x, skb, &esp); if (esp.nfrags < 0) return esp.nfrags; } seq = xo->seq.low; esph = esp.esph; esph->spi = x->id.spi; skb_push(skb, -skb_network_offset(skb)); if (xo->flags & XFRM_GSO_SEGMENT) { esph->seq_no = htonl(seq); if (!skb_is_gso(skb)) xo->seq.low++; else xo->seq.low += skb_shinfo(skb)->gso_segs; } if (xo->seq.low < seq) xo->seq.hi++; esp.seqno = cpu_to_be64(seq + ((u64)xo->seq.hi << 32)); ip_hdr(skb)->tot_len = htons(skb->len); ip_send_check(ip_hdr(skb)); if (hw_offload) { if (!skb_ext_add(skb, SKB_EXT_SEC_PATH)) return -ENOMEM; xo = xfrm_offload(skb); if (!xo) return -EINVAL; xo->flags |= XFRM_XMIT; return 0; } err = esp_output_tail(x, skb, &esp); if (err) return err; secpath_reset(skb); if (skb_needs_linearize(skb, skb->dev->features) && __skb_linearize(skb)) return -ENOMEM; return 0; } static const struct net_offload esp4_offload = { .callbacks = { .gro_receive = esp4_gro_receive, .gso_segment = esp4_gso_segment, }, }; static const struct xfrm_type_offload esp_type_offload = { .owner = THIS_MODULE, .proto = IPPROTO_ESP, .input_tail = esp_input_tail, .xmit = esp_xmit, .encap = esp4_gso_encap, }; static int __init esp4_offload_init(void) { if (xfrm_register_type_offload(&esp_type_offload, AF_INET) < 0) { pr_info("%s: can't add xfrm type offload\n", __func__); return -EAGAIN; } return inet_add_offload(&esp4_offload, IPPROTO_ESP); } static void __exit esp4_offload_exit(void) { xfrm_unregister_type_offload(&esp_type_offload, AF_INET); inet_del_offload(&esp4_offload, IPPROTO_ESP); } module_init(esp4_offload_init); module_exit(esp4_offload_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Steffen Klassert <[email protected]>"); MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET, XFRM_PROTO_ESP); MODULE_DESCRIPTION("IPV4 GSO/GRO offload support");
linux-master
net/ipv4/esp4_offload.c
// SPDX-License-Identifier: GPL-2.0-only /* * TCP Vegas congestion control * * This is based on the congestion detection/avoidance scheme described in * Lawrence S. Brakmo and Larry L. Peterson. * "TCP Vegas: End to end congestion avoidance on a global internet." * IEEE Journal on Selected Areas in Communication, 13(8):1465--1480, * October 1995. Available from: * ftp://ftp.cs.arizona.edu/xkernel/Papers/jsac.ps * * See http://www.cs.arizona.edu/xkernel/ for their implementation. * The main aspects that distinguish this implementation from the * Arizona Vegas implementation are: * o We do not change the loss detection or recovery mechanisms of * Linux in any way. Linux already recovers from losses quite well, * using fine-grained timers, NewReno, and FACK. * o To avoid the performance penalty imposed by increasing cwnd * only every-other RTT during slow start, we increase during * every RTT during slow start, just like Reno. * o Largely to allow continuous cwnd growth during slow start, * we use the rate at which ACKs come back as the "actual" * rate, rather than the rate at which data is sent. * o To speed convergence to the right rate, we set the cwnd * to achieve the right ("actual") rate when we exit slow start. * o To filter out the noise caused by delayed ACKs, we use the * minimum RTT sample observed during the last RTT to calculate * the actual rate. * o When the sender re-starts from idle, it waits until it has * received ACKs for an entire flight of new data before making * a cwnd adjustment decision. The original Vegas implementation * assumed senders never went idle. */ #include <linux/mm.h> #include <linux/module.h> #include <linux/skbuff.h> #include <linux/inet_diag.h> #include <net/tcp.h> #include "tcp_vegas.h" static int alpha = 2; static int beta = 4; static int gamma = 1; module_param(alpha, int, 0644); MODULE_PARM_DESC(alpha, "lower bound of packets in network"); module_param(beta, int, 0644); MODULE_PARM_DESC(beta, "upper bound of packets in network"); module_param(gamma, int, 0644); MODULE_PARM_DESC(gamma, "limit on increase (scale by 2)"); /* There are several situations when we must "re-start" Vegas: * * o when a connection is established * o after an RTO * o after fast recovery * o when we send a packet and there is no outstanding * unacknowledged data (restarting an idle connection) * * In these circumstances we cannot do a Vegas calculation at the * end of the first RTT, because any calculation we do is using * stale info -- both the saved cwnd and congestion feedback are * stale. * * Instead we must wait until the completion of an RTT during * which we actually receive ACKs. */ static void vegas_enable(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct vegas *vegas = inet_csk_ca(sk); /* Begin taking Vegas samples next time we send something. */ vegas->doing_vegas_now = 1; /* Set the beginning of the next send window. */ vegas->beg_snd_nxt = tp->snd_nxt; vegas->cntRTT = 0; vegas->minRTT = 0x7fffffff; } /* Stop taking Vegas samples for now. */ static inline void vegas_disable(struct sock *sk) { struct vegas *vegas = inet_csk_ca(sk); vegas->doing_vegas_now = 0; } void tcp_vegas_init(struct sock *sk) { struct vegas *vegas = inet_csk_ca(sk); vegas->baseRTT = 0x7fffffff; vegas_enable(sk); } EXPORT_SYMBOL_GPL(tcp_vegas_init); /* Do RTT sampling needed for Vegas. * Basically we: * o min-filter RTT samples from within an RTT to get the current * propagation delay + queuing delay (we are min-filtering to try to * avoid the effects of delayed ACKs) * o min-filter RTT samples from a much longer window (forever for now) * to find the propagation delay (baseRTT) */ void tcp_vegas_pkts_acked(struct sock *sk, const struct ack_sample *sample) { struct vegas *vegas = inet_csk_ca(sk); u32 vrtt; if (sample->rtt_us < 0) return; /* Never allow zero rtt or baseRTT */ vrtt = sample->rtt_us + 1; /* Filter to find propagation delay: */ if (vrtt < vegas->baseRTT) vegas->baseRTT = vrtt; /* Find the min RTT during the last RTT to find * the current prop. delay + queuing delay: */ vegas->minRTT = min(vegas->minRTT, vrtt); vegas->cntRTT++; } EXPORT_SYMBOL_GPL(tcp_vegas_pkts_acked); void tcp_vegas_state(struct sock *sk, u8 ca_state) { if (ca_state == TCP_CA_Open) vegas_enable(sk); else vegas_disable(sk); } EXPORT_SYMBOL_GPL(tcp_vegas_state); /* * If the connection is idle and we are restarting, * then we don't want to do any Vegas calculations * until we get fresh RTT samples. So when we * restart, we reset our Vegas state to a clean * slate. After we get acks for this flight of * packets, _then_ we can make Vegas calculations * again. */ void tcp_vegas_cwnd_event(struct sock *sk, enum tcp_ca_event event) { if (event == CA_EVENT_CWND_RESTART || event == CA_EVENT_TX_START) tcp_vegas_init(sk); } EXPORT_SYMBOL_GPL(tcp_vegas_cwnd_event); static inline u32 tcp_vegas_ssthresh(struct tcp_sock *tp) { return min(tp->snd_ssthresh, tcp_snd_cwnd(tp)); } static void tcp_vegas_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct vegas *vegas = inet_csk_ca(sk); if (!vegas->doing_vegas_now) { tcp_reno_cong_avoid(sk, ack, acked); return; } if (after(ack, vegas->beg_snd_nxt)) { /* Do the Vegas once-per-RTT cwnd adjustment. */ /* Save the extent of the current window so we can use this * at the end of the next RTT. */ vegas->beg_snd_nxt = tp->snd_nxt; /* We do the Vegas calculations only if we got enough RTT * samples that we can be reasonably sure that we got * at least one RTT sample that wasn't from a delayed ACK. * If we only had 2 samples total, * then that means we're getting only 1 ACK per RTT, which * means they're almost certainly delayed ACKs. * If we have 3 samples, we should be OK. */ if (vegas->cntRTT <= 2) { /* We don't have enough RTT samples to do the Vegas * calculation, so we'll behave like Reno. */ tcp_reno_cong_avoid(sk, ack, acked); } else { u32 rtt, diff; u64 target_cwnd; /* We have enough RTT samples, so, using the Vegas * algorithm, we determine if we should increase or * decrease cwnd, and by how much. */ /* Pluck out the RTT we are using for the Vegas * calculations. This is the min RTT seen during the * last RTT. Taking the min filters out the effects * of delayed ACKs, at the cost of noticing congestion * a bit later. */ rtt = vegas->minRTT; /* Calculate the cwnd we should have, if we weren't * going too fast. * * This is: * (actual rate in segments) * baseRTT */ target_cwnd = (u64)tcp_snd_cwnd(tp) * vegas->baseRTT; do_div(target_cwnd, rtt); /* Calculate the difference between the window we had, * and the window we would like to have. This quantity * is the "Diff" from the Arizona Vegas papers. */ diff = tcp_snd_cwnd(tp) * (rtt-vegas->baseRTT) / vegas->baseRTT; if (diff > gamma && tcp_in_slow_start(tp)) { /* Going too fast. Time to slow down * and switch to congestion avoidance. */ /* Set cwnd to match the actual rate * exactly: * cwnd = (actual rate) * baseRTT * Then we add 1 because the integer * truncation robs us of full link * utilization. */ tcp_snd_cwnd_set(tp, min(tcp_snd_cwnd(tp), (u32)target_cwnd + 1)); tp->snd_ssthresh = tcp_vegas_ssthresh(tp); } else if (tcp_in_slow_start(tp)) { /* Slow start. */ tcp_slow_start(tp, acked); } else { /* Congestion avoidance. */ /* Figure out where we would like cwnd * to be. */ if (diff > beta) { /* The old window was too fast, so * we slow down. */ tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) - 1); tp->snd_ssthresh = tcp_vegas_ssthresh(tp); } else if (diff < alpha) { /* We don't have enough extra packets * in the network, so speed up. */ tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) + 1); } else { /* Sending just as fast as we * should be. */ } } if (tcp_snd_cwnd(tp) < 2) tcp_snd_cwnd_set(tp, 2); else if (tcp_snd_cwnd(tp) > tp->snd_cwnd_clamp) tcp_snd_cwnd_set(tp, tp->snd_cwnd_clamp); tp->snd_ssthresh = tcp_current_ssthresh(sk); } /* Wipe the slate clean for the next RTT. */ vegas->cntRTT = 0; vegas->minRTT = 0x7fffffff; } /* Use normal slow start */ else if (tcp_in_slow_start(tp)) tcp_slow_start(tp, acked); } /* Extract info for Tcp socket info provided via netlink. */ size_t tcp_vegas_get_info(struct sock *sk, u32 ext, int *attr, union tcp_cc_info *info) { const struct vegas *ca = inet_csk_ca(sk); if (ext & (1 << (INET_DIAG_VEGASINFO - 1))) { info->vegas.tcpv_enabled = ca->doing_vegas_now; info->vegas.tcpv_rttcnt = ca->cntRTT; info->vegas.tcpv_rtt = ca->baseRTT; info->vegas.tcpv_minrtt = ca->minRTT; *attr = INET_DIAG_VEGASINFO; return sizeof(struct tcpvegas_info); } return 0; } EXPORT_SYMBOL_GPL(tcp_vegas_get_info); static struct tcp_congestion_ops tcp_vegas __read_mostly = { .init = tcp_vegas_init, .ssthresh = tcp_reno_ssthresh, .undo_cwnd = tcp_reno_undo_cwnd, .cong_avoid = tcp_vegas_cong_avoid, .pkts_acked = tcp_vegas_pkts_acked, .set_state = tcp_vegas_state, .cwnd_event = tcp_vegas_cwnd_event, .get_info = tcp_vegas_get_info, .owner = THIS_MODULE, .name = "vegas", }; static int __init tcp_vegas_register(void) { BUILD_BUG_ON(sizeof(struct vegas) > ICSK_CA_PRIV_SIZE); tcp_register_congestion_control(&tcp_vegas); return 0; } static void __exit tcp_vegas_unregister(void) { tcp_unregister_congestion_control(&tcp_vegas); } module_init(tcp_vegas_register); module_exit(tcp_vegas_unregister); MODULE_AUTHOR("Stephen Hemminger"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("TCP Vegas");
linux-master
net/ipv4/tcp_vegas.c
// SPDX-License-Identifier: GPL-2.0-only /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Implementation of the Transmission Control Protocol(TCP). * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * Mark Evans, <[email protected]> * Corey Minyard <[email protected]> * Florian La Roche, <[email protected]> * Charles Hedrick, <[email protected]> * Linus Torvalds, <[email protected]> * Alan Cox, <[email protected]> * Matthew Dillon, <[email protected]> * Arnt Gulbrandsen, <[email protected]> * Jorge Cwik, <[email protected]> */ #include <linux/module.h> #include <linux/gfp.h> #include <net/tcp.h> static u32 tcp_clamp_rto_to_user_timeout(const struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); u32 elapsed, start_ts, user_timeout; s32 remaining; start_ts = tcp_sk(sk)->retrans_stamp; user_timeout = READ_ONCE(icsk->icsk_user_timeout); if (!user_timeout) return icsk->icsk_rto; elapsed = tcp_time_stamp(tcp_sk(sk)) - start_ts; remaining = user_timeout - elapsed; if (remaining <= 0) return 1; /* user timeout has passed; fire ASAP */ return min_t(u32, icsk->icsk_rto, msecs_to_jiffies(remaining)); } u32 tcp_clamp_probe0_to_user_timeout(const struct sock *sk, u32 when) { struct inet_connection_sock *icsk = inet_csk(sk); u32 remaining, user_timeout; s32 elapsed; user_timeout = READ_ONCE(icsk->icsk_user_timeout); if (!user_timeout || !icsk->icsk_probes_tstamp) return when; elapsed = tcp_jiffies32 - icsk->icsk_probes_tstamp; if (unlikely(elapsed < 0)) elapsed = 0; remaining = msecs_to_jiffies(user_timeout) - elapsed; remaining = max_t(u32, remaining, TCP_TIMEOUT_MIN); return min_t(u32, remaining, when); } /** * tcp_write_err() - close socket and save error info * @sk: The socket the error has appeared on. * * Returns: Nothing (void) */ static void tcp_write_err(struct sock *sk) { WRITE_ONCE(sk->sk_err, READ_ONCE(sk->sk_err_soft) ? : ETIMEDOUT); sk_error_report(sk); tcp_write_queue_purge(sk); tcp_done(sk); __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONTIMEOUT); } /** * tcp_out_of_resources() - Close socket if out of resources * @sk: pointer to current socket * @do_reset: send a last packet with reset flag * * Do not allow orphaned sockets to eat all our resources. * This is direct violation of TCP specs, but it is required * to prevent DoS attacks. It is called when a retransmission timeout * or zero probe timeout occurs on orphaned socket. * * Also close if our net namespace is exiting; in that case there is no * hope of ever communicating again since all netns interfaces are already * down (or about to be down), and we need to release our dst references, * which have been moved to the netns loopback interface, so the namespace * can finish exiting. This condition is only possible if we are a kernel * socket, as those do not hold references to the namespace. * * Criteria is still not confirmed experimentally and may change. * We kill the socket, if: * 1. If number of orphaned sockets exceeds an administratively configured * limit. * 2. If we have strong memory pressure. * 3. If our net namespace is exiting. */ static int tcp_out_of_resources(struct sock *sk, bool do_reset) { struct tcp_sock *tp = tcp_sk(sk); int shift = 0; /* If peer does not open window for long time, or did not transmit * anything for long time, penalize it. */ if ((s32)(tcp_jiffies32 - tp->lsndtime) > 2*TCP_RTO_MAX || !do_reset) shift++; /* If some dubious ICMP arrived, penalize even more. */ if (READ_ONCE(sk->sk_err_soft)) shift++; if (tcp_check_oom(sk, shift)) { /* Catch exceptional cases, when connection requires reset. * 1. Last segment was sent recently. */ if ((s32)(tcp_jiffies32 - tp->lsndtime) <= TCP_TIMEWAIT_LEN || /* 2. Window is closed. */ (!tp->snd_wnd && !tp->packets_out)) do_reset = true; if (do_reset) tcp_send_active_reset(sk, GFP_ATOMIC); tcp_done(sk); __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONMEMORY); return 1; } if (!check_net(sock_net(sk))) { /* Not possible to send reset; just close */ tcp_done(sk); return 1; } return 0; } /** * tcp_orphan_retries() - Returns maximal number of retries on an orphaned socket * @sk: Pointer to the current socket. * @alive: bool, socket alive state */ static int tcp_orphan_retries(struct sock *sk, bool alive) { int retries = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_orphan_retries); /* May be zero. */ /* We know from an ICMP that something is wrong. */ if (READ_ONCE(sk->sk_err_soft) && !alive) retries = 0; /* However, if socket sent something recently, select some safe * number of retries. 8 corresponds to >100 seconds with minimal * RTO of 200msec. */ if (retries == 0 && alive) retries = 8; return retries; } static void tcp_mtu_probing(struct inet_connection_sock *icsk, struct sock *sk) { const struct net *net = sock_net(sk); int mss; /* Black hole detection */ if (!READ_ONCE(net->ipv4.sysctl_tcp_mtu_probing)) return; if (!icsk->icsk_mtup.enabled) { icsk->icsk_mtup.enabled = 1; icsk->icsk_mtup.probe_timestamp = tcp_jiffies32; } else { mss = tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low) >> 1; mss = min(READ_ONCE(net->ipv4.sysctl_tcp_base_mss), mss); mss = max(mss, READ_ONCE(net->ipv4.sysctl_tcp_mtu_probe_floor)); mss = max(mss, READ_ONCE(net->ipv4.sysctl_tcp_min_snd_mss)); icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, mss); } tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); } static unsigned int tcp_model_timeout(struct sock *sk, unsigned int boundary, unsigned int rto_base) { unsigned int linear_backoff_thresh, timeout; linear_backoff_thresh = ilog2(TCP_RTO_MAX / rto_base); if (boundary <= linear_backoff_thresh) timeout = ((2 << boundary) - 1) * rto_base; else timeout = ((2 << linear_backoff_thresh) - 1) * rto_base + (boundary - linear_backoff_thresh) * TCP_RTO_MAX; return jiffies_to_msecs(timeout); } /** * retransmits_timed_out() - returns true if this connection has timed out * @sk: The current socket * @boundary: max number of retransmissions * @timeout: A custom timeout value. * If set to 0 the default timeout is calculated and used. * Using TCP_RTO_MIN and the number of unsuccessful retransmits. * * The default "timeout" value this function can calculate and use * is equivalent to the timeout of a TCP Connection * after "boundary" unsuccessful, exponentially backed-off * retransmissions with an initial RTO of TCP_RTO_MIN. */ static bool retransmits_timed_out(struct sock *sk, unsigned int boundary, unsigned int timeout) { unsigned int start_ts; if (!inet_csk(sk)->icsk_retransmits) return false; start_ts = tcp_sk(sk)->retrans_stamp; if (likely(timeout == 0)) { unsigned int rto_base = TCP_RTO_MIN; if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) rto_base = tcp_timeout_init(sk); timeout = tcp_model_timeout(sk, boundary, rto_base); } return (s32)(tcp_time_stamp(tcp_sk(sk)) - start_ts - timeout) >= 0; } /* A write timeout has occurred. Process the after effects. */ static int tcp_write_timeout(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); bool expired = false, do_reset; int retry_until, max_retransmits; if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) { if (icsk->icsk_retransmits) __dst_negative_advice(sk); /* Paired with WRITE_ONCE() in tcp_sock_set_syncnt() */ retry_until = READ_ONCE(icsk->icsk_syn_retries) ? : READ_ONCE(net->ipv4.sysctl_tcp_syn_retries); max_retransmits = retry_until; if (sk->sk_state == TCP_SYN_SENT) max_retransmits += READ_ONCE(net->ipv4.sysctl_tcp_syn_linear_timeouts); expired = icsk->icsk_retransmits >= max_retransmits; } else { if (retransmits_timed_out(sk, READ_ONCE(net->ipv4.sysctl_tcp_retries1), 0)) { /* Black hole detection */ tcp_mtu_probing(icsk, sk); __dst_negative_advice(sk); } retry_until = READ_ONCE(net->ipv4.sysctl_tcp_retries2); if (sock_flag(sk, SOCK_DEAD)) { const bool alive = icsk->icsk_rto < TCP_RTO_MAX; retry_until = tcp_orphan_retries(sk, alive); do_reset = alive || !retransmits_timed_out(sk, retry_until, 0); if (tcp_out_of_resources(sk, do_reset)) return 1; } } if (!expired) expired = retransmits_timed_out(sk, retry_until, READ_ONCE(icsk->icsk_user_timeout)); tcp_fastopen_active_detect_blackhole(sk, expired); if (BPF_SOCK_OPS_TEST_FLAG(tp, BPF_SOCK_OPS_RTO_CB_FLAG)) tcp_call_bpf_3arg(sk, BPF_SOCK_OPS_RTO_CB, icsk->icsk_retransmits, icsk->icsk_rto, (int)expired); if (expired) { /* Has it gone just too far? */ tcp_write_err(sk); return 1; } if (sk_rethink_txhash(sk)) { tp->timeout_rehash++; __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEOUTREHASH); } return 0; } /* Called with BH disabled */ void tcp_delack_timer_handler(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); if ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)) return; /* Handling the sack compression case */ if (tp->compressed_ack) { tcp_mstamp_refresh(tp); tcp_sack_compress_send_ack(sk); return; } if (!(icsk->icsk_ack.pending & ICSK_ACK_TIMER)) return; if (time_after(icsk->icsk_ack.timeout, jiffies)) { sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); return; } icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER; if (inet_csk_ack_scheduled(sk)) { if (!inet_csk_in_pingpong_mode(sk)) { /* Delayed ACK missed: inflate ATO. */ icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, icsk->icsk_rto); } else { /* Delayed ACK missed: leave pingpong mode and * deflate ATO. */ inet_csk_exit_pingpong_mode(sk); icsk->icsk_ack.ato = TCP_ATO_MIN; } tcp_mstamp_refresh(tp); tcp_send_ack(sk); __NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKS); } } /** * tcp_delack_timer() - The TCP delayed ACK timeout handler * @t: Pointer to the timer. (gets casted to struct sock *) * * This function gets (indirectly) called when the kernel timer for a TCP packet * of this socket expires. Calls tcp_delack_timer_handler() to do the actual work. * * Returns: Nothing (void) */ static void tcp_delack_timer(struct timer_list *t) { struct inet_connection_sock *icsk = from_timer(icsk, t, icsk_delack_timer); struct sock *sk = &icsk->icsk_inet.sk; bh_lock_sock(sk); if (!sock_owned_by_user(sk)) { tcp_delack_timer_handler(sk); } else { __NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED); /* deleguate our work to tcp_release_cb() */ if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, &sk->sk_tsq_flags)) sock_hold(sk); } bh_unlock_sock(sk); sock_put(sk); } static void tcp_probe_timer(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct sk_buff *skb = tcp_send_head(sk); struct tcp_sock *tp = tcp_sk(sk); int max_probes; if (tp->packets_out || !skb) { icsk->icsk_probes_out = 0; icsk->icsk_probes_tstamp = 0; return; } /* RFC 1122 4.2.2.17 requires the sender to stay open indefinitely as * long as the receiver continues to respond probes. We support this by * default and reset icsk_probes_out with incoming ACKs. But if the * socket is orphaned or the user specifies TCP_USER_TIMEOUT, we * kill the socket when the retry count and the time exceeds the * corresponding system limit. We also implement similar policy when * we use RTO to probe window in tcp_retransmit_timer(). */ if (!icsk->icsk_probes_tstamp) { icsk->icsk_probes_tstamp = tcp_jiffies32; } else { u32 user_timeout = READ_ONCE(icsk->icsk_user_timeout); if (user_timeout && (s32)(tcp_jiffies32 - icsk->icsk_probes_tstamp) >= msecs_to_jiffies(user_timeout)) goto abort; } max_probes = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_retries2); if (sock_flag(sk, SOCK_DEAD)) { const bool alive = inet_csk_rto_backoff(icsk, TCP_RTO_MAX) < TCP_RTO_MAX; max_probes = tcp_orphan_retries(sk, alive); if (!alive && icsk->icsk_backoff >= max_probes) goto abort; if (tcp_out_of_resources(sk, true)) return; } if (icsk->icsk_probes_out >= max_probes) { abort: tcp_write_err(sk); } else { /* Only send another probe if we didn't close things up. */ tcp_send_probe0(sk); } } /* * Timer for Fast Open socket to retransmit SYNACK. Note that the * sk here is the child socket, not the parent (listener) socket. */ static void tcp_fastopen_synack_timer(struct sock *sk, struct request_sock *req) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); int max_retries; req->rsk_ops->syn_ack_timeout(req); /* Add one more retry for fastopen. * Paired with WRITE_ONCE() in tcp_sock_set_syncnt() */ max_retries = READ_ONCE(icsk->icsk_syn_retries) ? : READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_synack_retries) + 1; if (req->num_timeout >= max_retries) { tcp_write_err(sk); return; } /* Lower cwnd after certain SYNACK timeout like tcp_init_transfer() */ if (icsk->icsk_retransmits == 1) tcp_enter_loss(sk); /* XXX (TFO) - Unlike regular SYN-ACK retransmit, we ignore error * returned from rtx_syn_ack() to make it more persistent like * regular retransmit because if the child socket has been accepted * it's not good to give up too easily. */ inet_rtx_syn_ack(sk, req); req->num_timeout++; icsk->icsk_retransmits++; if (!tp->retrans_stamp) tp->retrans_stamp = tcp_time_stamp(tp); inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, req->timeout << req->num_timeout, TCP_RTO_MAX); } static bool tcp_rtx_probe0_timed_out(const struct sock *sk, const struct sk_buff *skb) { const struct tcp_sock *tp = tcp_sk(sk); const int timeout = TCP_RTO_MAX * 2; u32 rcv_delta, rtx_delta; rcv_delta = inet_csk(sk)->icsk_timeout - tp->rcv_tstamp; if (rcv_delta <= timeout) return false; rtx_delta = (u32)msecs_to_jiffies(tcp_time_stamp(tp) - (tp->retrans_stamp ?: tcp_skb_timestamp(skb))); return rtx_delta > timeout; } /** * tcp_retransmit_timer() - The TCP retransmit timeout handler * @sk: Pointer to the current socket. * * This function gets called when the kernel timer for a TCP packet * of this socket expires. * * It handles retransmission, timer adjustment and other necessary measures. * * Returns: Nothing (void) */ void tcp_retransmit_timer(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); struct inet_connection_sock *icsk = inet_csk(sk); struct request_sock *req; struct sk_buff *skb; req = rcu_dereference_protected(tp->fastopen_rsk, lockdep_sock_is_held(sk)); if (req) { WARN_ON_ONCE(sk->sk_state != TCP_SYN_RECV && sk->sk_state != TCP_FIN_WAIT1); tcp_fastopen_synack_timer(sk, req); /* Before we receive ACK to our SYN-ACK don't retransmit * anything else (e.g., data or FIN segments). */ return; } if (!tp->packets_out) return; skb = tcp_rtx_queue_head(sk); if (WARN_ON_ONCE(!skb)) return; tp->tlp_high_seq = 0; if (!tp->snd_wnd && !sock_flag(sk, SOCK_DEAD) && !((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))) { /* Receiver dastardly shrinks window. Our retransmits * become zero probes, but we should not timeout this * connection. If the socket is an orphan, time it out, * we cannot allow such beasts to hang infinitely. */ struct inet_sock *inet = inet_sk(sk); u32 rtx_delta; rtx_delta = tcp_time_stamp(tp) - (tp->retrans_stamp ?: tcp_skb_timestamp(skb)); if (sk->sk_family == AF_INET) { net_dbg_ratelimited("Probing zero-window on %pI4:%u/%u, seq=%u:%u, recv %ums ago, lasting %ums\n", &inet->inet_daddr, ntohs(inet->inet_dport), inet->inet_num, tp->snd_una, tp->snd_nxt, jiffies_to_msecs(jiffies - tp->rcv_tstamp), rtx_delta); } #if IS_ENABLED(CONFIG_IPV6) else if (sk->sk_family == AF_INET6) { net_dbg_ratelimited("Probing zero-window on %pI6:%u/%u, seq=%u:%u, recv %ums ago, lasting %ums\n", &sk->sk_v6_daddr, ntohs(inet->inet_dport), inet->inet_num, tp->snd_una, tp->snd_nxt, jiffies_to_msecs(jiffies - tp->rcv_tstamp), rtx_delta); } #endif if (tcp_rtx_probe0_timed_out(sk, skb)) { tcp_write_err(sk); goto out; } tcp_enter_loss(sk); tcp_retransmit_skb(sk, skb, 1); __sk_dst_reset(sk); goto out_reset_timer; } __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEOUTS); if (tcp_write_timeout(sk)) goto out; if (icsk->icsk_retransmits == 0) { int mib_idx = 0; if (icsk->icsk_ca_state == TCP_CA_Recovery) { if (tcp_is_sack(tp)) mib_idx = LINUX_MIB_TCPSACKRECOVERYFAIL; else mib_idx = LINUX_MIB_TCPRENORECOVERYFAIL; } else if (icsk->icsk_ca_state == TCP_CA_Loss) { mib_idx = LINUX_MIB_TCPLOSSFAILURES; } else if ((icsk->icsk_ca_state == TCP_CA_Disorder) || tp->sacked_out) { if (tcp_is_sack(tp)) mib_idx = LINUX_MIB_TCPSACKFAILURES; else mib_idx = LINUX_MIB_TCPRENOFAILURES; } if (mib_idx) __NET_INC_STATS(sock_net(sk), mib_idx); } tcp_enter_loss(sk); icsk->icsk_retransmits++; if (tcp_retransmit_skb(sk, tcp_rtx_queue_head(sk), 1) > 0) { /* Retransmission failed because of local congestion, * Let senders fight for local resources conservatively. */ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, TCP_RESOURCE_PROBE_INTERVAL, TCP_RTO_MAX); goto out; } /* Increase the timeout each time we retransmit. Note that * we do not increase the rtt estimate. rto is initialized * from rtt, but increases here. Jacobson (SIGCOMM 88) suggests * that doubling rto each time is the least we can get away with. * In KA9Q, Karn uses this for the first few times, and then * goes to quadratic. netBSD doubles, but only goes up to *64, * and clamps at 1 to 64 sec afterwards. Note that 120 sec is * defined in the protocol as the maximum possible RTT. I guess * we'll have to use something other than TCP to talk to the * University of Mars. * * PAWS allows us longer timeouts and large windows, so once * implemented ftp to mars will work nicely. We will have to fix * the 120 second clamps though! */ icsk->icsk_backoff++; out_reset_timer: /* If stream is thin, use linear timeouts. Since 'icsk_backoff' is * used to reset timer, set to 0. Recalculate 'icsk_rto' as this * might be increased if the stream oscillates between thin and thick, * thus the old value might already be too high compared to the value * set by 'tcp_set_rto' in tcp_input.c which resets the rto without * backoff. Limit to TCP_THIN_LINEAR_RETRIES before initiating * exponential backoff behaviour to avoid continue hammering * linear-timeout retransmissions into a black hole */ if (sk->sk_state == TCP_ESTABLISHED && (tp->thin_lto || READ_ONCE(net->ipv4.sysctl_tcp_thin_linear_timeouts)) && tcp_stream_is_thin(tp) && icsk->icsk_retransmits <= TCP_THIN_LINEAR_RETRIES) { icsk->icsk_backoff = 0; icsk->icsk_rto = clamp(__tcp_set_rto(tp), tcp_rto_min(sk), TCP_RTO_MAX); } else if (sk->sk_state != TCP_SYN_SENT || icsk->icsk_backoff > READ_ONCE(net->ipv4.sysctl_tcp_syn_linear_timeouts)) { /* Use normal (exponential) backoff unless linear timeouts are * activated. */ icsk->icsk_rto = min(icsk->icsk_rto << 1, TCP_RTO_MAX); } inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, tcp_clamp_rto_to_user_timeout(sk), TCP_RTO_MAX); if (retransmits_timed_out(sk, READ_ONCE(net->ipv4.sysctl_tcp_retries1) + 1, 0)) __sk_dst_reset(sk); out:; } /* Called with bottom-half processing disabled. Called by tcp_write_timer() */ void tcp_write_timer_handler(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); int event; if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)) || !icsk->icsk_pending) return; if (time_after(icsk->icsk_timeout, jiffies)) { sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); return; } tcp_mstamp_refresh(tcp_sk(sk)); event = icsk->icsk_pending; switch (event) { case ICSK_TIME_REO_TIMEOUT: tcp_rack_reo_timeout(sk); break; case ICSK_TIME_LOSS_PROBE: tcp_send_loss_probe(sk); break; case ICSK_TIME_RETRANS: icsk->icsk_pending = 0; tcp_retransmit_timer(sk); break; case ICSK_TIME_PROBE0: icsk->icsk_pending = 0; tcp_probe_timer(sk); break; } } static void tcp_write_timer(struct timer_list *t) { struct inet_connection_sock *icsk = from_timer(icsk, t, icsk_retransmit_timer); struct sock *sk = &icsk->icsk_inet.sk; bh_lock_sock(sk); if (!sock_owned_by_user(sk)) { tcp_write_timer_handler(sk); } else { /* delegate our work to tcp_release_cb() */ if (!test_and_set_bit(TCP_WRITE_TIMER_DEFERRED, &sk->sk_tsq_flags)) sock_hold(sk); } bh_unlock_sock(sk); sock_put(sk); } void tcp_syn_ack_timeout(const struct request_sock *req) { struct net *net = read_pnet(&inet_rsk(req)->ireq_net); __NET_INC_STATS(net, LINUX_MIB_TCPTIMEOUTS); } EXPORT_SYMBOL(tcp_syn_ack_timeout); void tcp_set_keepalive(struct sock *sk, int val) { if ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)) return; if (val && !sock_flag(sk, SOCK_KEEPOPEN)) inet_csk_reset_keepalive_timer(sk, keepalive_time_when(tcp_sk(sk))); else if (!val) inet_csk_delete_keepalive_timer(sk); } EXPORT_SYMBOL_GPL(tcp_set_keepalive); static void tcp_keepalive_timer (struct timer_list *t) { struct sock *sk = from_timer(sk, t, sk_timer); struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); u32 elapsed; /* Only process if socket is not in use. */ bh_lock_sock(sk); if (sock_owned_by_user(sk)) { /* Try again later. */ inet_csk_reset_keepalive_timer (sk, HZ/20); goto out; } if (sk->sk_state == TCP_LISTEN) { pr_err("Hmm... keepalive on a LISTEN ???\n"); goto out; } tcp_mstamp_refresh(tp); if (sk->sk_state == TCP_FIN_WAIT2 && sock_flag(sk, SOCK_DEAD)) { if (READ_ONCE(tp->linger2) >= 0) { const int tmo = tcp_fin_time(sk) - TCP_TIMEWAIT_LEN; if (tmo > 0) { tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); goto out; } } tcp_send_active_reset(sk, GFP_ATOMIC); goto death; } if (!sock_flag(sk, SOCK_KEEPOPEN) || ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT))) goto out; elapsed = keepalive_time_when(tp); /* It is alive without keepalive 8) */ if (tp->packets_out || !tcp_write_queue_empty(sk)) goto resched; elapsed = keepalive_time_elapsed(tp); if (elapsed >= keepalive_time_when(tp)) { u32 user_timeout = READ_ONCE(icsk->icsk_user_timeout); /* If the TCP_USER_TIMEOUT option is enabled, use that * to determine when to timeout instead. */ if ((user_timeout != 0 && elapsed >= msecs_to_jiffies(user_timeout) && icsk->icsk_probes_out > 0) || (user_timeout == 0 && icsk->icsk_probes_out >= keepalive_probes(tp))) { tcp_send_active_reset(sk, GFP_ATOMIC); tcp_write_err(sk); goto out; } if (tcp_write_wakeup(sk, LINUX_MIB_TCPKEEPALIVE) <= 0) { icsk->icsk_probes_out++; elapsed = keepalive_intvl_when(tp); } else { /* If keepalive was lost due to local congestion, * try harder. */ elapsed = TCP_RESOURCE_PROBE_INTERVAL; } } else { /* It is tp->rcv_tstamp + keepalive_time_when(tp) */ elapsed = keepalive_time_when(tp) - elapsed; } resched: inet_csk_reset_keepalive_timer (sk, elapsed); goto out; death: tcp_done(sk); out: bh_unlock_sock(sk); sock_put(sk); } static enum hrtimer_restart tcp_compressed_ack_kick(struct hrtimer *timer) { struct tcp_sock *tp = container_of(timer, struct tcp_sock, compressed_ack_timer); struct sock *sk = (struct sock *)tp; bh_lock_sock(sk); if (!sock_owned_by_user(sk)) { if (tp->compressed_ack) { /* Since we have to send one ack finally, * subtract one from tp->compressed_ack to keep * LINUX_MIB_TCPACKCOMPRESSED accurate. */ tp->compressed_ack--; tcp_send_ack(sk); } } else { if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, &sk->sk_tsq_flags)) sock_hold(sk); } bh_unlock_sock(sk); sock_put(sk); return HRTIMER_NORESTART; } void tcp_init_xmit_timers(struct sock *sk) { inet_csk_init_xmit_timers(sk, &tcp_write_timer, &tcp_delack_timer, &tcp_keepalive_timer); hrtimer_init(&tcp_sk(sk)->pacing_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_SOFT); tcp_sk(sk)->pacing_timer.function = tcp_pace_kick; hrtimer_init(&tcp_sk(sk)->compressed_ack_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED_SOFT); tcp_sk(sk)->compressed_ack_timer.function = tcp_compressed_ack_kick; }
linux-master
net/ipv4/tcp_timer.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * IPV4 GSO/GRO offload support * Linux INET implementation * * UDPv4 GSO support */ #include <linux/skbuff.h> #include <net/gro.h> #include <net/gso.h> #include <net/udp.h> #include <net/protocol.h> #include <net/inet_common.h> static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, netdev_features_t features, struct sk_buff *(*gso_inner_segment)(struct sk_buff *skb, netdev_features_t features), __be16 new_protocol, bool is_ipv6) { int tnl_hlen = skb_inner_mac_header(skb) - skb_transport_header(skb); bool remcsum, need_csum, offload_csum, gso_partial; struct sk_buff *segs = ERR_PTR(-EINVAL); struct udphdr *uh = udp_hdr(skb); u16 mac_offset = skb->mac_header; __be16 protocol = skb->protocol; u16 mac_len = skb->mac_len; int udp_offset, outer_hlen; __wsum partial; bool need_ipsec; if (unlikely(!pskb_may_pull(skb, tnl_hlen))) goto out; /* Adjust partial header checksum to negate old length. * We cannot rely on the value contained in uh->len as it is * possible that the actual value exceeds the boundaries of the * 16 bit length field due to the header being added outside of an * IP or IPv6 frame that was already limited to 64K - 1. */ if (skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) partial = (__force __wsum)uh->len; else partial = (__force __wsum)htonl(skb->len); partial = csum_sub(csum_unfold(uh->check), partial); /* setup inner skb. */ skb->encapsulation = 0; SKB_GSO_CB(skb)->encap_level = 0; __skb_pull(skb, tnl_hlen); skb_reset_mac_header(skb); skb_set_network_header(skb, skb_inner_network_offset(skb)); skb_set_transport_header(skb, skb_inner_transport_offset(skb)); skb->mac_len = skb_inner_network_offset(skb); skb->protocol = new_protocol; need_csum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM); skb->encap_hdr_csum = need_csum; remcsum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TUNNEL_REMCSUM); skb->remcsum_offload = remcsum; need_ipsec = skb_dst(skb) && dst_xfrm(skb_dst(skb)); /* Try to offload checksum if possible */ offload_csum = !!(need_csum && !need_ipsec && (skb->dev->features & (is_ipv6 ? (NETIF_F_HW_CSUM | NETIF_F_IPV6_CSUM) : (NETIF_F_HW_CSUM | NETIF_F_IP_CSUM)))); features &= skb->dev->hw_enc_features; if (need_csum) features &= ~NETIF_F_SCTP_CRC; /* The only checksum offload we care about from here on out is the * outer one so strip the existing checksum feature flags and * instead set the flag based on our outer checksum offload value. */ if (remcsum) { features &= ~NETIF_F_CSUM_MASK; if (!need_csum || offload_csum) features |= NETIF_F_HW_CSUM; } /* segment inner packet. */ segs = gso_inner_segment(skb, features); if (IS_ERR_OR_NULL(segs)) { skb_gso_error_unwind(skb, protocol, tnl_hlen, mac_offset, mac_len); goto out; } gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL); outer_hlen = skb_tnl_header_len(skb); udp_offset = outer_hlen - tnl_hlen; skb = segs; do { unsigned int len; if (remcsum) skb->ip_summed = CHECKSUM_NONE; /* Set up inner headers if we are offloading inner checksum */ if (skb->ip_summed == CHECKSUM_PARTIAL) { skb_reset_inner_headers(skb); skb->encapsulation = 1; } skb->mac_len = mac_len; skb->protocol = protocol; __skb_push(skb, outer_hlen); skb_reset_mac_header(skb); skb_set_network_header(skb, mac_len); skb_set_transport_header(skb, udp_offset); len = skb->len - udp_offset; uh = udp_hdr(skb); /* If we are only performing partial GSO the inner header * will be using a length value equal to only one MSS sized * segment instead of the entire frame. */ if (gso_partial && skb_is_gso(skb)) { uh->len = htons(skb_shinfo(skb)->gso_size + SKB_GSO_CB(skb)->data_offset + skb->head - (unsigned char *)uh); } else { uh->len = htons(len); } if (!need_csum) continue; uh->check = ~csum_fold(csum_add(partial, (__force __wsum)htonl(len))); if (skb->encapsulation || !offload_csum) { uh->check = gso_make_checksum(skb, ~uh->check); if (uh->check == 0) uh->check = CSUM_MANGLED_0; } else { skb->ip_summed = CHECKSUM_PARTIAL; skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = offsetof(struct udphdr, check); } } while ((skb = skb->next)); out: return segs; } struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb, netdev_features_t features, bool is_ipv6) { const struct net_offload __rcu **offloads; __be16 protocol = skb->protocol; const struct net_offload *ops; struct sk_buff *segs = ERR_PTR(-EINVAL); struct sk_buff *(*gso_inner_segment)(struct sk_buff *skb, netdev_features_t features); rcu_read_lock(); switch (skb->inner_protocol_type) { case ENCAP_TYPE_ETHER: protocol = skb->inner_protocol; gso_inner_segment = skb_mac_gso_segment; break; case ENCAP_TYPE_IPPROTO: offloads = is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[skb->inner_ipproto]); if (!ops || !ops->callbacks.gso_segment) goto out_unlock; gso_inner_segment = ops->callbacks.gso_segment; break; default: goto out_unlock; } segs = __skb_udp_tunnel_segment(skb, features, gso_inner_segment, protocol, is_ipv6); out_unlock: rcu_read_unlock(); return segs; } EXPORT_SYMBOL(skb_udp_tunnel_segment); static void __udpv4_gso_segment_csum(struct sk_buff *seg, __be32 *oldip, __be32 *newip, __be16 *oldport, __be16 *newport) { struct udphdr *uh; struct iphdr *iph; if (*oldip == *newip && *oldport == *newport) return; uh = udp_hdr(seg); iph = ip_hdr(seg); if (uh->check) { inet_proto_csum_replace4(&uh->check, seg, *oldip, *newip, true); inet_proto_csum_replace2(&uh->check, seg, *oldport, *newport, false); if (!uh->check) uh->check = CSUM_MANGLED_0; } *oldport = *newport; csum_replace4(&iph->check, *oldip, *newip); *oldip = *newip; } static struct sk_buff *__udpv4_gso_segment_list_csum(struct sk_buff *segs) { struct sk_buff *seg; struct udphdr *uh, *uh2; struct iphdr *iph, *iph2; seg = segs; uh = udp_hdr(seg); iph = ip_hdr(seg); if ((udp_hdr(seg)->dest == udp_hdr(seg->next)->dest) && (udp_hdr(seg)->source == udp_hdr(seg->next)->source) && (ip_hdr(seg)->daddr == ip_hdr(seg->next)->daddr) && (ip_hdr(seg)->saddr == ip_hdr(seg->next)->saddr)) return segs; while ((seg = seg->next)) { uh2 = udp_hdr(seg); iph2 = ip_hdr(seg); __udpv4_gso_segment_csum(seg, &iph2->saddr, &iph->saddr, &uh2->source, &uh->source); __udpv4_gso_segment_csum(seg, &iph2->daddr, &iph->daddr, &uh2->dest, &uh->dest); } return segs; } static struct sk_buff *__udp_gso_segment_list(struct sk_buff *skb, netdev_features_t features, bool is_ipv6) { unsigned int mss = skb_shinfo(skb)->gso_size; skb = skb_segment_list(skb, features, skb_mac_header_len(skb)); if (IS_ERR(skb)) return skb; udp_hdr(skb)->len = htons(sizeof(struct udphdr) + mss); return is_ipv6 ? skb : __udpv4_gso_segment_list_csum(skb); } struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb, netdev_features_t features, bool is_ipv6) { struct sock *sk = gso_skb->sk; unsigned int sum_truesize = 0; struct sk_buff *segs, *seg; struct udphdr *uh; unsigned int mss; bool copy_dtor; __sum16 check; __be16 newlen; mss = skb_shinfo(gso_skb)->gso_size; if (gso_skb->len <= sizeof(*uh) + mss) return ERR_PTR(-EINVAL); if (skb_gso_ok(gso_skb, features | NETIF_F_GSO_ROBUST)) { /* Packet is from an untrusted source, reset gso_segs. */ skb_shinfo(gso_skb)->gso_segs = DIV_ROUND_UP(gso_skb->len - sizeof(*uh), mss); return NULL; } if (skb_shinfo(gso_skb)->gso_type & SKB_GSO_FRAGLIST) return __udp_gso_segment_list(gso_skb, features, is_ipv6); skb_pull(gso_skb, sizeof(*uh)); /* clear destructor to avoid skb_segment assigning it to tail */ copy_dtor = gso_skb->destructor == sock_wfree; if (copy_dtor) gso_skb->destructor = NULL; segs = skb_segment(gso_skb, features); if (IS_ERR_OR_NULL(segs)) { if (copy_dtor) gso_skb->destructor = sock_wfree; return segs; } /* GSO partial and frag_list segmentation only requires splitting * the frame into an MSS multiple and possibly a remainder, both * cases return a GSO skb. So update the mss now. */ if (skb_is_gso(segs)) mss *= skb_shinfo(segs)->gso_segs; seg = segs; uh = udp_hdr(seg); /* preserve TX timestamp flags and TS key for first segment */ skb_shinfo(seg)->tskey = skb_shinfo(gso_skb)->tskey; skb_shinfo(seg)->tx_flags |= (skb_shinfo(gso_skb)->tx_flags & SKBTX_ANY_TSTAMP); /* compute checksum adjustment based on old length versus new */ newlen = htons(sizeof(*uh) + mss); check = csum16_add(csum16_sub(uh->check, uh->len), newlen); for (;;) { if (copy_dtor) { seg->destructor = sock_wfree; seg->sk = sk; sum_truesize += seg->truesize; } if (!seg->next) break; uh->len = newlen; uh->check = check; if (seg->ip_summed == CHECKSUM_PARTIAL) gso_reset_checksum(seg, ~check); else uh->check = gso_make_checksum(seg, ~check) ? : CSUM_MANGLED_0; seg = seg->next; uh = udp_hdr(seg); } /* last packet can be partial gso_size, account for that in checksum */ newlen = htons(skb_tail_pointer(seg) - skb_transport_header(seg) + seg->data_len); check = csum16_add(csum16_sub(uh->check, uh->len), newlen); uh->len = newlen; uh->check = check; if (seg->ip_summed == CHECKSUM_PARTIAL) gso_reset_checksum(seg, ~check); else uh->check = gso_make_checksum(seg, ~check) ? : CSUM_MANGLED_0; /* update refcount for the packet */ if (copy_dtor) { int delta = sum_truesize - gso_skb->truesize; /* In some pathological cases, delta can be negative. * We need to either use refcount_add() or refcount_sub_and_test() */ if (likely(delta >= 0)) refcount_add(delta, &sk->sk_wmem_alloc); else WARN_ON_ONCE(refcount_sub_and_test(-delta, &sk->sk_wmem_alloc)); } return segs; } EXPORT_SYMBOL_GPL(__udp_gso_segment); static struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, netdev_features_t features) { struct sk_buff *segs = ERR_PTR(-EINVAL); unsigned int mss; __wsum csum; struct udphdr *uh; struct iphdr *iph; if (skb->encapsulation && (skb_shinfo(skb)->gso_type & (SKB_GSO_UDP_TUNNEL|SKB_GSO_UDP_TUNNEL_CSUM))) { segs = skb_udp_tunnel_segment(skb, features, false); goto out; } if (!(skb_shinfo(skb)->gso_type & (SKB_GSO_UDP | SKB_GSO_UDP_L4))) goto out; if (!pskb_may_pull(skb, sizeof(struct udphdr))) goto out; if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) return __udp_gso_segment(skb, features, false); mss = skb_shinfo(skb)->gso_size; if (unlikely(skb->len <= mss)) goto out; /* Do software UFO. Complete and fill in the UDP checksum as * HW cannot do checksum of UDP packets sent as multiple * IP fragments. */ uh = udp_hdr(skb); iph = ip_hdr(skb); uh->check = 0; csum = skb_checksum(skb, 0, skb->len, 0); uh->check = udp_v4_check(skb->len, iph->saddr, iph->daddr, csum); if (uh->check == 0) uh->check = CSUM_MANGLED_0; skb->ip_summed = CHECKSUM_UNNECESSARY; /* If there is no outer header we can fake a checksum offload * due to the fact that we have already done the checksum in * software prior to segmenting the frame. */ if (!skb->encap_hdr_csum) features |= NETIF_F_HW_CSUM; /* Fragment the skb. IP headers of the fragments are updated in * inet_gso_segment() */ segs = skb_segment(skb, features); out: return segs; } static int skb_gro_receive_list(struct sk_buff *p, struct sk_buff *skb) { if (unlikely(p->len + skb->len >= 65536)) return -E2BIG; if (NAPI_GRO_CB(p)->last == p) skb_shinfo(p)->frag_list = skb; else NAPI_GRO_CB(p)->last->next = skb; skb_pull(skb, skb_gro_offset(skb)); NAPI_GRO_CB(p)->last = skb; NAPI_GRO_CB(p)->count++; p->data_len += skb->len; /* sk owenrship - if any - completely transferred to the aggregated packet */ skb->destructor = NULL; p->truesize += skb->truesize; p->len += skb->len; NAPI_GRO_CB(skb)->same_flow = 1; return 0; } #define UDP_GRO_CNT_MAX 64 static struct sk_buff *udp_gro_receive_segment(struct list_head *head, struct sk_buff *skb) { struct udphdr *uh = udp_gro_udphdr(skb); struct sk_buff *pp = NULL; struct udphdr *uh2; struct sk_buff *p; unsigned int ulen; int ret = 0; /* requires non zero csum, for symmetry with GSO */ if (!uh->check) { NAPI_GRO_CB(skb)->flush = 1; return NULL; } /* Do not deal with padded or malicious packets, sorry ! */ ulen = ntohs(uh->len); if (ulen <= sizeof(*uh) || ulen != skb_gro_len(skb)) { NAPI_GRO_CB(skb)->flush = 1; return NULL; } /* pull encapsulating udp header */ skb_gro_pull(skb, sizeof(struct udphdr)); list_for_each_entry(p, head, list) { if (!NAPI_GRO_CB(p)->same_flow) continue; uh2 = udp_hdr(p); /* Match ports only, as csum is always non zero */ if ((*(u32 *)&uh->source != *(u32 *)&uh2->source)) { NAPI_GRO_CB(p)->same_flow = 0; continue; } if (NAPI_GRO_CB(skb)->is_flist != NAPI_GRO_CB(p)->is_flist) { NAPI_GRO_CB(skb)->flush = 1; return p; } /* Terminate the flow on len mismatch or if it grow "too much". * Under small packet flood GRO count could elsewhere grow a lot * leading to excessive truesize values. * On len mismatch merge the first packet shorter than gso_size, * otherwise complete the GRO packet. */ if (ulen > ntohs(uh2->len)) { pp = p; } else { if (NAPI_GRO_CB(skb)->is_flist) { if (!pskb_may_pull(skb, skb_gro_offset(skb))) { NAPI_GRO_CB(skb)->flush = 1; return NULL; } if ((skb->ip_summed != p->ip_summed) || (skb->csum_level != p->csum_level)) { NAPI_GRO_CB(skb)->flush = 1; return NULL; } ret = skb_gro_receive_list(p, skb); } else { skb_gro_postpull_rcsum(skb, uh, sizeof(struct udphdr)); ret = skb_gro_receive(p, skb); } } if (ret || ulen != ntohs(uh2->len) || NAPI_GRO_CB(p)->count >= UDP_GRO_CNT_MAX) pp = p; return pp; } /* mismatch, but we never need to flush */ return NULL; } struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb, struct udphdr *uh, struct sock *sk) { struct sk_buff *pp = NULL; struct sk_buff *p; struct udphdr *uh2; unsigned int off = skb_gro_offset(skb); int flush = 1; /* we can do L4 aggregation only if the packet can't land in a tunnel * otherwise we could corrupt the inner stream */ NAPI_GRO_CB(skb)->is_flist = 0; if (!sk || !udp_sk(sk)->gro_receive) { if (skb->dev->features & NETIF_F_GRO_FRAGLIST) NAPI_GRO_CB(skb)->is_flist = sk ? !udp_sk(sk)->gro_enabled : 1; if ((!sk && (skb->dev->features & NETIF_F_GRO_UDP_FWD)) || (sk && udp_sk(sk)->gro_enabled) || NAPI_GRO_CB(skb)->is_flist) return call_gro_receive(udp_gro_receive_segment, head, skb); /* no GRO, be sure flush the current packet */ goto out; } if (NAPI_GRO_CB(skb)->encap_mark || (uh->check && skb->ip_summed != CHECKSUM_PARTIAL && NAPI_GRO_CB(skb)->csum_cnt == 0 && !NAPI_GRO_CB(skb)->csum_valid)) goto out; /* mark that this skb passed once through the tunnel gro layer */ NAPI_GRO_CB(skb)->encap_mark = 1; flush = 0; list_for_each_entry(p, head, list) { if (!NAPI_GRO_CB(p)->same_flow) continue; uh2 = (struct udphdr *)(p->data + off); /* Match ports and either checksums are either both zero * or nonzero. */ if ((*(u32 *)&uh->source != *(u32 *)&uh2->source) || (!uh->check ^ !uh2->check)) { NAPI_GRO_CB(p)->same_flow = 0; continue; } } skb_gro_pull(skb, sizeof(struct udphdr)); /* pull encapsulating udp header */ skb_gro_postpull_rcsum(skb, uh, sizeof(struct udphdr)); pp = call_gro_receive_sk(udp_sk(sk)->gro_receive, sk, head, skb); out: skb_gro_flush_final(skb, pp, flush); return pp; } EXPORT_SYMBOL(udp_gro_receive); static struct sock *udp4_gro_lookup_skb(struct sk_buff *skb, __be16 sport, __be16 dport) { const struct iphdr *iph = skb_gro_network_header(skb); struct net *net = dev_net(skb->dev); int iif, sdif; inet_get_iif_sdif(skb, &iif, &sdif); return __udp4_lib_lookup(net, iph->saddr, sport, iph->daddr, dport, iif, sdif, net->ipv4.udp_table, NULL); } INDIRECT_CALLABLE_SCOPE struct sk_buff *udp4_gro_receive(struct list_head *head, struct sk_buff *skb) { struct udphdr *uh = udp_gro_udphdr(skb); struct sock *sk = NULL; struct sk_buff *pp; if (unlikely(!uh)) goto flush; /* Don't bother verifying checksum if we're going to flush anyway. */ if (NAPI_GRO_CB(skb)->flush) goto skip; if (skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check, inet_gro_compute_pseudo)) goto flush; else if (uh->check) skb_gro_checksum_try_convert(skb, IPPROTO_UDP, inet_gro_compute_pseudo); skip: NAPI_GRO_CB(skb)->is_ipv6 = 0; if (static_branch_unlikely(&udp_encap_needed_key)) sk = udp4_gro_lookup_skb(skb, uh->source, uh->dest); pp = udp_gro_receive(head, skb, uh, sk); return pp; flush: NAPI_GRO_CB(skb)->flush = 1; return NULL; } static int udp_gro_complete_segment(struct sk_buff *skb) { struct udphdr *uh = udp_hdr(skb); skb->csum_start = (unsigned char *)uh - skb->head; skb->csum_offset = offsetof(struct udphdr, check); skb->ip_summed = CHECKSUM_PARTIAL; skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count; skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_L4; if (skb->encapsulation) skb->inner_transport_header = skb->transport_header; return 0; } int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup) { __be16 newlen = htons(skb->len - nhoff); struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); struct sock *sk; int err; uh->len = newlen; sk = INDIRECT_CALL_INET(lookup, udp6_lib_lookup_skb, udp4_lib_lookup_skb, skb, uh->source, uh->dest); if (sk && udp_sk(sk)->gro_complete) { skb_shinfo(skb)->gso_type = uh->check ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL; /* clear the encap mark, so that inner frag_list gro_complete * can take place */ NAPI_GRO_CB(skb)->encap_mark = 0; /* Set encapsulation before calling into inner gro_complete() * functions to make them set up the inner offsets. */ skb->encapsulation = 1; err = udp_sk(sk)->gro_complete(sk, skb, nhoff + sizeof(struct udphdr)); } else { err = udp_gro_complete_segment(skb); } if (skb->remcsum_offload) skb_shinfo(skb)->gso_type |= SKB_GSO_TUNNEL_REMCSUM; return err; } EXPORT_SYMBOL(udp_gro_complete); INDIRECT_CALLABLE_SCOPE int udp4_gro_complete(struct sk_buff *skb, int nhoff) { const struct iphdr *iph = ip_hdr(skb); struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); /* do fraglist only if there is no outer UDP encap (or we already processed it) */ if (NAPI_GRO_CB(skb)->is_flist && !NAPI_GRO_CB(skb)->encap_mark) { uh->len = htons(skb->len - nhoff); skb_shinfo(skb)->gso_type |= (SKB_GSO_FRAGLIST|SKB_GSO_UDP_L4); skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count; if (skb->ip_summed == CHECKSUM_UNNECESSARY) { if (skb->csum_level < SKB_MAX_CSUM_LEVEL) skb->csum_level++; } else { skb->ip_summed = CHECKSUM_UNNECESSARY; skb->csum_level = 0; } return 0; } if (uh->check) uh->check = ~udp_v4_check(skb->len - nhoff, iph->saddr, iph->daddr, 0); return udp_gro_complete(skb, nhoff, udp4_lib_lookup_skb); } static const struct net_offload udpv4_offload = { .callbacks = { .gso_segment = udp4_ufo_fragment, .gro_receive = udp4_gro_receive, .gro_complete = udp4_gro_complete, }, }; int __init udpv4_offload_init(void) { return inet_add_offload(&udpv4_offload, IPPROTO_UDP); }
linux-master
net/ipv4/udp_offload.c
// SPDX-License-Identifier: GPL-2.0 #include <linux/tcp.h> #include <net/tcp.h> static u32 tcp_rack_reo_wnd(const struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); if (!tp->reord_seen) { /* If reordering has not been observed, be aggressive during * the recovery or starting the recovery by DUPACK threshold. */ if (inet_csk(sk)->icsk_ca_state >= TCP_CA_Recovery) return 0; if (tp->sacked_out >= tp->reordering && !(READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_recovery) & TCP_RACK_NO_DUPTHRESH)) return 0; } /* To be more reordering resilient, allow min_rtt/4 settling delay. * Use min_rtt instead of the smoothed RTT because reordering is * often a path property and less related to queuing or delayed ACKs. * Upon receiving DSACKs, linearly increase the window up to the * smoothed RTT. */ return min((tcp_min_rtt(tp) >> 2) * tp->rack.reo_wnd_steps, tp->srtt_us >> 3); } s32 tcp_rack_skb_timeout(struct tcp_sock *tp, struct sk_buff *skb, u32 reo_wnd) { return tp->rack.rtt_us + reo_wnd - tcp_stamp_us_delta(tp->tcp_mstamp, tcp_skb_timestamp_us(skb)); } /* RACK loss detection (IETF draft draft-ietf-tcpm-rack-01): * * Marks a packet lost, if some packet sent later has been (s)acked. * The underlying idea is similar to the traditional dupthresh and FACK * but they look at different metrics: * * dupthresh: 3 OOO packets delivered (packet count) * FACK: sequence delta to highest sacked sequence (sequence space) * RACK: sent time delta to the latest delivered packet (time domain) * * The advantage of RACK is it applies to both original and retransmitted * packet and therefore is robust against tail losses. Another advantage * is being more resilient to reordering by simply allowing some * "settling delay", instead of tweaking the dupthresh. * * When tcp_rack_detect_loss() detects some packets are lost and we * are not already in the CA_Recovery state, either tcp_rack_reo_timeout() * or tcp_time_to_recover()'s "Trick#1: the loss is proven" code path will * make us enter the CA_Recovery state. */ static void tcp_rack_detect_loss(struct sock *sk, u32 *reo_timeout) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb, *n; u32 reo_wnd; *reo_timeout = 0; reo_wnd = tcp_rack_reo_wnd(sk); list_for_each_entry_safe(skb, n, &tp->tsorted_sent_queue, tcp_tsorted_anchor) { struct tcp_skb_cb *scb = TCP_SKB_CB(skb); s32 remaining; /* Skip ones marked lost but not yet retransmitted */ if ((scb->sacked & TCPCB_LOST) && !(scb->sacked & TCPCB_SACKED_RETRANS)) continue; if (!tcp_skb_sent_after(tp->rack.mstamp, tcp_skb_timestamp_us(skb), tp->rack.end_seq, scb->end_seq)) break; /* A packet is lost if it has not been s/acked beyond * the recent RTT plus the reordering window. */ remaining = tcp_rack_skb_timeout(tp, skb, reo_wnd); if (remaining <= 0) { tcp_mark_skb_lost(sk, skb); list_del_init(&skb->tcp_tsorted_anchor); } else { /* Record maximum wait time */ *reo_timeout = max_t(u32, *reo_timeout, remaining); } } } bool tcp_rack_mark_lost(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); u32 timeout; if (!tp->rack.advanced) return false; /* Reset the advanced flag to avoid unnecessary queue scanning */ tp->rack.advanced = 0; tcp_rack_detect_loss(sk, &timeout); if (timeout) { timeout = usecs_to_jiffies(timeout) + TCP_TIMEOUT_MIN; inet_csk_reset_xmit_timer(sk, ICSK_TIME_REO_TIMEOUT, timeout, inet_csk(sk)->icsk_rto); } return !!timeout; } /* Record the most recently (re)sent time among the (s)acked packets * This is "Step 3: Advance RACK.xmit_time and update RACK.RTT" from * draft-cheng-tcpm-rack-00.txt */ void tcp_rack_advance(struct tcp_sock *tp, u8 sacked, u32 end_seq, u64 xmit_time) { u32 rtt_us; rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, xmit_time); if (rtt_us < tcp_min_rtt(tp) && (sacked & TCPCB_RETRANS)) { /* If the sacked packet was retransmitted, it's ambiguous * whether the retransmission or the original (or the prior * retransmission) was sacked. * * If the original is lost, there is no ambiguity. Otherwise * we assume the original can be delayed up to aRTT + min_rtt. * the aRTT term is bounded by the fast recovery or timeout, * so it's at least one RTT (i.e., retransmission is at least * an RTT later). */ return; } tp->rack.advanced = 1; tp->rack.rtt_us = rtt_us; if (tcp_skb_sent_after(xmit_time, tp->rack.mstamp, end_seq, tp->rack.end_seq)) { tp->rack.mstamp = xmit_time; tp->rack.end_seq = end_seq; } } /* We have waited long enough to accommodate reordering. Mark the expired * packets lost and retransmit them. */ void tcp_rack_reo_timeout(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); u32 timeout, prior_inflight; u32 lost = tp->lost; prior_inflight = tcp_packets_in_flight(tp); tcp_rack_detect_loss(sk, &timeout); if (prior_inflight != tcp_packets_in_flight(tp)) { if (inet_csk(sk)->icsk_ca_state != TCP_CA_Recovery) { tcp_enter_recovery(sk, false); if (!inet_csk(sk)->icsk_ca_ops->cong_control) tcp_cwnd_reduction(sk, 1, tp->lost - lost, 0); } tcp_xmit_retransmit_queue(sk); } if (inet_csk(sk)->icsk_pending != ICSK_TIME_RETRANS) tcp_rearm_rto(sk); } /* Updates the RACK's reo_wnd based on DSACK and no. of recoveries. * * If a DSACK is received that seems like it may have been due to reordering * triggering fast recovery, increment reo_wnd by min_rtt/4 (upper bounded * by srtt), since there is possibility that spurious retransmission was * due to reordering delay longer than reo_wnd. * * Persist the current reo_wnd value for TCP_RACK_RECOVERY_THRESH (16) * no. of successful recoveries (accounts for full DSACK-based loss * recovery undo). After that, reset it to default (min_rtt/4). * * At max, reo_wnd is incremented only once per rtt. So that the new * DSACK on which we are reacting, is due to the spurious retx (approx) * after the reo_wnd has been updated last time. * * reo_wnd is tracked in terms of steps (of min_rtt/4), rather than * absolute value to account for change in rtt. */ void tcp_rack_update_reo_wnd(struct sock *sk, struct rate_sample *rs) { struct tcp_sock *tp = tcp_sk(sk); if ((READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_recovery) & TCP_RACK_STATIC_REO_WND) || !rs->prior_delivered) return; /* Disregard DSACK if a rtt has not passed since we adjusted reo_wnd */ if (before(rs->prior_delivered, tp->rack.last_delivered)) tp->rack.dsack_seen = 0; /* Adjust the reo_wnd if update is pending */ if (tp->rack.dsack_seen) { tp->rack.reo_wnd_steps = min_t(u32, 0xFF, tp->rack.reo_wnd_steps + 1); tp->rack.dsack_seen = 0; tp->rack.last_delivered = tp->delivered; tp->rack.reo_wnd_persist = TCP_RACK_RECOVERY_THRESH; } else if (!tp->rack.reo_wnd_persist) { tp->rack.reo_wnd_steps = 1; } } /* RFC6582 NewReno recovery for non-SACK connection. It simply retransmits * the next unacked packet upon receiving * a) three or more DUPACKs to start the fast recovery * b) an ACK acknowledging new data during the fast recovery. */ void tcp_newreno_mark_lost(struct sock *sk, bool snd_una_advanced) { const u8 state = inet_csk(sk)->icsk_ca_state; struct tcp_sock *tp = tcp_sk(sk); if ((state < TCP_CA_Recovery && tp->sacked_out >= tp->reordering) || (state == TCP_CA_Recovery && snd_una_advanced)) { struct sk_buff *skb = tcp_rtx_queue_head(sk); u32 mss; if (TCP_SKB_CB(skb)->sacked & TCPCB_LOST) return; mss = tcp_skb_mss(skb); if (tcp_skb_pcount(skb) > 1 && skb->len > mss) tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb, mss, mss, GFP_ATOMIC); tcp_mark_skb_lost(sk, skb); } }
linux-master
net/ipv4/tcp_recovery.c
// SPDX-License-Identifier: GPL-2.0 #include <linux/rtnetlink.h> #include <linux/notifier.h> #include <linux/socket.h> #include <linux/kernel.h> #include <linux/export.h> #include <net/net_namespace.h> #include <net/fib_notifier.h> #include <net/ip_fib.h> int call_fib4_notifier(struct notifier_block *nb, enum fib_event_type event_type, struct fib_notifier_info *info) { info->family = AF_INET; return call_fib_notifier(nb, event_type, info); } int call_fib4_notifiers(struct net *net, enum fib_event_type event_type, struct fib_notifier_info *info) { ASSERT_RTNL(); info->family = AF_INET; net->ipv4.fib_seq++; return call_fib_notifiers(net, event_type, info); } static unsigned int fib4_seq_read(struct net *net) { ASSERT_RTNL(); return net->ipv4.fib_seq + fib4_rules_seq_read(net); } static int fib4_dump(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { int err; err = fib4_rules_dump(net, nb, extack); if (err) return err; return fib_notify(net, nb, extack); } static const struct fib_notifier_ops fib4_notifier_ops_template = { .family = AF_INET, .fib_seq_read = fib4_seq_read, .fib_dump = fib4_dump, .owner = THIS_MODULE, }; int __net_init fib4_notifier_init(struct net *net) { struct fib_notifier_ops *ops; net->ipv4.fib_seq = 0; ops = fib_notifier_ops_register(&fib4_notifier_ops_template, net); if (IS_ERR(ops)) return PTR_ERR(ops); net->ipv4.notifier_ops = ops; return 0; } void __net_exit fib4_notifier_exit(struct net *net) { fib_notifier_ops_unregister(net->ipv4.notifier_ops); }
linux-master
net/ipv4/fib_notifier.c
/* * INETPEER - A storage for permanent information about peers * * This source is covered by the GNU GPL, the same as all kernel sources. * * Authors: Andrey V. Savochkin <[email protected]> */ #include <linux/cache.h> #include <linux/module.h> #include <linux/types.h> #include <linux/slab.h> #include <linux/interrupt.h> #include <linux/spinlock.h> #include <linux/random.h> #include <linux/timer.h> #include <linux/time.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/net.h> #include <linux/workqueue.h> #include <net/ip.h> #include <net/inetpeer.h> #include <net/secure_seq.h> /* * Theory of operations. * We keep one entry for each peer IP address. The nodes contains long-living * information about the peer which doesn't depend on routes. * * Nodes are removed only when reference counter goes to 0. * When it's happened the node may be removed when a sufficient amount of * time has been passed since its last use. The less-recently-used entry can * also be removed if the pool is overloaded i.e. if the total amount of * entries is greater-or-equal than the threshold. * * Node pool is organised as an RB tree. * Such an implementation has been chosen not just for fun. It's a way to * prevent easy and efficient DoS attacks by creating hash collisions. A huge * amount of long living nodes in a single hash slot would significantly delay * lookups performed with disabled BHs. * * Serialisation issues. * 1. Nodes may appear in the tree only with the pool lock held. * 2. Nodes may disappear from the tree only with the pool lock held * AND reference count being 0. * 3. Global variable peer_total is modified under the pool lock. * 4. struct inet_peer fields modification: * rb_node: pool lock * refcnt: atomically against modifications on other CPU; * usually under some other lock to prevent node disappearing * daddr: unchangeable */ static struct kmem_cache *peer_cachep __ro_after_init; void inet_peer_base_init(struct inet_peer_base *bp) { bp->rb_root = RB_ROOT; seqlock_init(&bp->lock); bp->total = 0; } EXPORT_SYMBOL_GPL(inet_peer_base_init); #define PEER_MAX_GC 32 /* Exported for sysctl_net_ipv4. */ int inet_peer_threshold __read_mostly; /* start to throw entries more * aggressively at this stage */ int inet_peer_minttl __read_mostly = 120 * HZ; /* TTL under high load: 120 sec */ int inet_peer_maxttl __read_mostly = 10 * 60 * HZ; /* usual time to live: 10 min */ /* Called from ip_output.c:ip_init */ void __init inet_initpeers(void) { u64 nr_entries; /* 1% of physical memory */ nr_entries = div64_ul((u64)totalram_pages() << PAGE_SHIFT, 100 * L1_CACHE_ALIGN(sizeof(struct inet_peer))); inet_peer_threshold = clamp_val(nr_entries, 4096, 65536 + 128); peer_cachep = kmem_cache_create("inet_peer_cache", sizeof(struct inet_peer), 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL); } /* Called with rcu_read_lock() or base->lock held */ static struct inet_peer *lookup(const struct inetpeer_addr *daddr, struct inet_peer_base *base, unsigned int seq, struct inet_peer *gc_stack[], unsigned int *gc_cnt, struct rb_node **parent_p, struct rb_node ***pp_p) { struct rb_node **pp, *parent, *next; struct inet_peer *p; pp = &base->rb_root.rb_node; parent = NULL; while (1) { int cmp; next = rcu_dereference_raw(*pp); if (!next) break; parent = next; p = rb_entry(parent, struct inet_peer, rb_node); cmp = inetpeer_addr_cmp(daddr, &p->daddr); if (cmp == 0) { if (!refcount_inc_not_zero(&p->refcnt)) break; return p; } if (gc_stack) { if (*gc_cnt < PEER_MAX_GC) gc_stack[(*gc_cnt)++] = p; } else if (unlikely(read_seqretry(&base->lock, seq))) { break; } if (cmp == -1) pp = &next->rb_left; else pp = &next->rb_right; } *parent_p = parent; *pp_p = pp; return NULL; } static void inetpeer_free_rcu(struct rcu_head *head) { kmem_cache_free(peer_cachep, container_of(head, struct inet_peer, rcu)); } /* perform garbage collect on all items stacked during a lookup */ static void inet_peer_gc(struct inet_peer_base *base, struct inet_peer *gc_stack[], unsigned int gc_cnt) { int peer_threshold, peer_maxttl, peer_minttl; struct inet_peer *p; __u32 delta, ttl; int i; peer_threshold = READ_ONCE(inet_peer_threshold); peer_maxttl = READ_ONCE(inet_peer_maxttl); peer_minttl = READ_ONCE(inet_peer_minttl); if (base->total >= peer_threshold) ttl = 0; /* be aggressive */ else ttl = peer_maxttl - (peer_maxttl - peer_minttl) / HZ * base->total / peer_threshold * HZ; for (i = 0; i < gc_cnt; i++) { p = gc_stack[i]; /* The READ_ONCE() pairs with the WRITE_ONCE() * in inet_putpeer() */ delta = (__u32)jiffies - READ_ONCE(p->dtime); if (delta < ttl || !refcount_dec_if_one(&p->refcnt)) gc_stack[i] = NULL; } for (i = 0; i < gc_cnt; i++) { p = gc_stack[i]; if (p) { rb_erase(&p->rb_node, &base->rb_root); base->total--; call_rcu(&p->rcu, inetpeer_free_rcu); } } } struct inet_peer *inet_getpeer(struct inet_peer_base *base, const struct inetpeer_addr *daddr, int create) { struct inet_peer *p, *gc_stack[PEER_MAX_GC]; struct rb_node **pp, *parent; unsigned int gc_cnt, seq; int invalidated; /* Attempt a lockless lookup first. * Because of a concurrent writer, we might not find an existing entry. */ rcu_read_lock(); seq = read_seqbegin(&base->lock); p = lookup(daddr, base, seq, NULL, &gc_cnt, &parent, &pp); invalidated = read_seqretry(&base->lock, seq); rcu_read_unlock(); if (p) return p; /* If no writer did a change during our lookup, we can return early. */ if (!create && !invalidated) return NULL; /* retry an exact lookup, taking the lock before. * At least, nodes should be hot in our cache. */ parent = NULL; write_seqlock_bh(&base->lock); gc_cnt = 0; p = lookup(daddr, base, seq, gc_stack, &gc_cnt, &parent, &pp); if (!p && create) { p = kmem_cache_alloc(peer_cachep, GFP_ATOMIC); if (p) { p->daddr = *daddr; p->dtime = (__u32)jiffies; refcount_set(&p->refcnt, 2); atomic_set(&p->rid, 0); p->metrics[RTAX_LOCK-1] = INETPEER_METRICS_NEW; p->rate_tokens = 0; p->n_redirects = 0; /* 60*HZ is arbitrary, but chosen enough high so that the first * calculation of tokens is at its maximum. */ p->rate_last = jiffies - 60*HZ; rb_link_node(&p->rb_node, parent, pp); rb_insert_color(&p->rb_node, &base->rb_root); base->total++; } } if (gc_cnt) inet_peer_gc(base, gc_stack, gc_cnt); write_sequnlock_bh(&base->lock); return p; } EXPORT_SYMBOL_GPL(inet_getpeer); void inet_putpeer(struct inet_peer *p) { /* The WRITE_ONCE() pairs with itself (we run lockless) * and the READ_ONCE() in inet_peer_gc() */ WRITE_ONCE(p->dtime, (__u32)jiffies); if (refcount_dec_and_test(&p->refcnt)) call_rcu(&p->rcu, inetpeer_free_rcu); } EXPORT_SYMBOL_GPL(inet_putpeer); /* * Check transmit rate limitation for given message. * The rate information is held in the inet_peer entries now. * This function is generic and could be used for other purposes * too. It uses a Token bucket filter as suggested by Alexey Kuznetsov. * * Note that the same inet_peer fields are modified by functions in * route.c too, but these work for packet destinations while xrlim_allow * works for icmp destinations. This means the rate limiting information * for one "ip object" is shared - and these ICMPs are twice limited: * by source and by destination. * * RFC 1812: 4.3.2.8 SHOULD be able to limit error message rate * SHOULD allow setting of rate limits * * Shared between ICMPv4 and ICMPv6. */ #define XRLIM_BURST_FACTOR 6 bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout) { unsigned long now, token; bool rc = false; if (!peer) return true; token = peer->rate_tokens; now = jiffies; token += now - peer->rate_last; peer->rate_last = now; if (token > XRLIM_BURST_FACTOR * timeout) token = XRLIM_BURST_FACTOR * timeout; if (token >= timeout) { token -= timeout; rc = true; } peer->rate_tokens = token; return rc; } EXPORT_SYMBOL(inet_peer_xrlim_allow); void inetpeer_invalidate_tree(struct inet_peer_base *base) { struct rb_node *p = rb_first(&base->rb_root); while (p) { struct inet_peer *peer = rb_entry(p, struct inet_peer, rb_node); p = rb_next(p); rb_erase(&peer->rb_node, &base->rb_root); inet_putpeer(peer); cond_resched(); } base->total = 0; } EXPORT_SYMBOL(inetpeer_invalidate_tree);
linux-master
net/ipv4/inetpeer.c
// SPDX-License-Identifier: GPL-2.0-only #include <linux/module.h> #include <linux/inet_diag.h> #include <linux/sock_diag.h> #include <net/inet_sock.h> #include <net/raw.h> #include <net/rawv6.h> #ifdef pr_fmt # undef pr_fmt #endif #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt static struct raw_hashinfo * raw_get_hashinfo(const struct inet_diag_req_v2 *r) { if (r->sdiag_family == AF_INET) { return &raw_v4_hashinfo; #if IS_ENABLED(CONFIG_IPV6) } else if (r->sdiag_family == AF_INET6) { return &raw_v6_hashinfo; #endif } else { return ERR_PTR(-EINVAL); } } /* * Due to requirement of not breaking user API we can't simply * rename @pad field in inet_diag_req_v2 structure, instead * use helper to figure it out. */ static bool raw_lookup(struct net *net, const struct sock *sk, const struct inet_diag_req_v2 *req) { struct inet_diag_req_raw *r = (void *)req; if (r->sdiag_family == AF_INET) return raw_v4_match(net, sk, r->sdiag_raw_protocol, r->id.idiag_dst[0], r->id.idiag_src[0], r->id.idiag_if, 0); #if IS_ENABLED(CONFIG_IPV6) else return raw_v6_match(net, sk, r->sdiag_raw_protocol, (const struct in6_addr *)r->id.idiag_src, (const struct in6_addr *)r->id.idiag_dst, r->id.idiag_if, 0); #endif return false; } static struct sock *raw_sock_get(struct net *net, const struct inet_diag_req_v2 *r) { struct raw_hashinfo *hashinfo = raw_get_hashinfo(r); struct hlist_head *hlist; struct sock *sk; int slot; if (IS_ERR(hashinfo)) return ERR_CAST(hashinfo); rcu_read_lock(); for (slot = 0; slot < RAW_HTABLE_SIZE; slot++) { hlist = &hashinfo->ht[slot]; sk_for_each_rcu(sk, hlist) { if (raw_lookup(net, sk, r)) { /* * Grab it and keep until we fill * diag message to be reported, so * caller should call sock_put then. */ if (refcount_inc_not_zero(&sk->sk_refcnt)) goto out_unlock; } } } sk = ERR_PTR(-ENOENT); out_unlock: rcu_read_unlock(); return sk; } static int raw_diag_dump_one(struct netlink_callback *cb, const struct inet_diag_req_v2 *r) { struct sk_buff *in_skb = cb->skb; struct sk_buff *rep; struct sock *sk; struct net *net; int err; net = sock_net(in_skb->sk); sk = raw_sock_get(net, r); if (IS_ERR(sk)) return PTR_ERR(sk); rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) + inet_diag_msg_attrs_size() + nla_total_size(sizeof(struct inet_diag_meminfo)) + 64, GFP_KERNEL); if (!rep) { sock_put(sk); return -ENOMEM; } err = inet_sk_diag_fill(sk, NULL, rep, cb, r, 0, netlink_net_capable(in_skb, CAP_NET_ADMIN)); sock_put(sk); if (err < 0) { kfree_skb(rep); return err; } err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid); return err; } static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *r, struct nlattr *bc, bool net_admin) { if (!inet_diag_bc_sk(bc, sk)) return 0; return inet_sk_diag_fill(sk, NULL, skb, cb, r, NLM_F_MULTI, net_admin); } static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *r) { bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); struct raw_hashinfo *hashinfo = raw_get_hashinfo(r); struct net *net = sock_net(skb->sk); struct inet_diag_dump_data *cb_data; int num, s_num, slot, s_slot; struct hlist_head *hlist; struct sock *sk = NULL; struct nlattr *bc; if (IS_ERR(hashinfo)) return; cb_data = cb->data; bc = cb_data->inet_diag_nla_bc; s_slot = cb->args[0]; num = s_num = cb->args[1]; rcu_read_lock(); for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) { num = 0; hlist = &hashinfo->ht[slot]; sk_for_each_rcu(sk, hlist) { struct inet_sock *inet = inet_sk(sk); if (!net_eq(sock_net(sk), net)) continue; if (num < s_num) goto next; if (sk->sk_family != r->sdiag_family) goto next; if (r->id.idiag_sport != inet->inet_sport && r->id.idiag_sport) goto next; if (r->id.idiag_dport != inet->inet_dport && r->id.idiag_dport) goto next; if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) goto out_unlock; next: num++; } } out_unlock: rcu_read_unlock(); cb->args[0] = slot; cb->args[1] = num; } static void raw_diag_get_info(struct sock *sk, struct inet_diag_msg *r, void *info) { r->idiag_rqueue = sk_rmem_alloc_get(sk); r->idiag_wqueue = sk_wmem_alloc_get(sk); } #ifdef CONFIG_INET_DIAG_DESTROY static int raw_diag_destroy(struct sk_buff *in_skb, const struct inet_diag_req_v2 *r) { struct net *net = sock_net(in_skb->sk); struct sock *sk; int err; sk = raw_sock_get(net, r); if (IS_ERR(sk)) return PTR_ERR(sk); err = sock_diag_destroy(sk, ECONNABORTED); sock_put(sk); return err; } #endif static const struct inet_diag_handler raw_diag_handler = { .dump = raw_diag_dump, .dump_one = raw_diag_dump_one, .idiag_get_info = raw_diag_get_info, .idiag_type = IPPROTO_RAW, .idiag_info_size = 0, #ifdef CONFIG_INET_DIAG_DESTROY .destroy = raw_diag_destroy, #endif }; static void __always_unused __check_inet_diag_req_raw(void) { /* * Make sure the two structures are identical, * except the @pad field. */ #define __offset_mismatch(m1, m2) \ (offsetof(struct inet_diag_req_v2, m1) != \ offsetof(struct inet_diag_req_raw, m2)) BUILD_BUG_ON(sizeof(struct inet_diag_req_v2) != sizeof(struct inet_diag_req_raw)); BUILD_BUG_ON(__offset_mismatch(sdiag_family, sdiag_family)); BUILD_BUG_ON(__offset_mismatch(sdiag_protocol, sdiag_protocol)); BUILD_BUG_ON(__offset_mismatch(idiag_ext, idiag_ext)); BUILD_BUG_ON(__offset_mismatch(pad, sdiag_raw_protocol)); BUILD_BUG_ON(__offset_mismatch(idiag_states, idiag_states)); BUILD_BUG_ON(__offset_mismatch(id, id)); #undef __offset_mismatch } static int __init raw_diag_init(void) { return inet_diag_register(&raw_diag_handler); } static void __exit raw_diag_exit(void) { inet_diag_unregister(&raw_diag_handler); } module_init(raw_diag_init); module_exit(raw_diag_exit); MODULE_LICENSE("GPL"); MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-255 /* AF_INET - IPPROTO_RAW */); MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10-255 /* AF_INET6 - IPPROTO_RAW */);
linux-master
net/ipv4/raw_diag.c
// SPDX-License-Identifier: GPL-2.0-or-later /* linux/net/ipv4/arp.c * * Copyright (C) 1994 by Florian La Roche * * This module implements the Address Resolution Protocol ARP (RFC 826), * which is used to convert IP addresses (or in the future maybe other * high-level addresses) into a low-level hardware address (like an Ethernet * address). * * Fixes: * Alan Cox : Removed the Ethernet assumptions in * Florian's code * Alan Cox : Fixed some small errors in the ARP * logic * Alan Cox : Allow >4K in /proc * Alan Cox : Make ARP add its own protocol entry * Ross Martin : Rewrote arp_rcv() and arp_get_info() * Stephen Henson : Add AX25 support to arp_get_info() * Alan Cox : Drop data when a device is downed. * Alan Cox : Use init_timer(). * Alan Cox : Double lock fixes. * Martin Seine : Move the arphdr structure * to if_arp.h for compatibility. * with BSD based programs. * Andrew Tridgell : Added ARP netmask code and * re-arranged proxy handling. * Alan Cox : Changed to use notifiers. * Niibe Yutaka : Reply for this device or proxies only. * Alan Cox : Don't proxy across hardware types! * Jonathan Naylor : Added support for NET/ROM. * Mike Shaver : RFC1122 checks. * Jonathan Naylor : Only lookup the hardware address for * the correct hardware type. * Germano Caronni : Assorted subtle races. * Craig Schlenter : Don't modify permanent entry * during arp_rcv. * Russ Nelson : Tidied up a few bits. * Alexey Kuznetsov: Major changes to caching and behaviour, * eg intelligent arp probing and * generation * of host down events. * Alan Cox : Missing unlock in device events. * Eckes : ARP ioctl control errors. * Alexey Kuznetsov: Arp free fix. * Manuel Rodriguez: Gratuitous ARP. * Jonathan Layes : Added arpd support through kerneld * message queue (960314) * Mike Shaver : /proc/sys/net/ipv4/arp_* support * Mike McLagan : Routing by source * Stuart Cheshire : Metricom and grat arp fixes * *** FOR 2.1 clean this up *** * Lawrence V. Stefani: (08/12/96) Added FDDI support. * Alan Cox : Took the AP1000 nasty FDDI hack and * folded into the mainstream FDDI code. * Ack spit, Linus how did you allow that * one in... * Jes Sorensen : Make FDDI work again in 2.1.x and * clean up the APFDDI & gen. FDDI bits. * Alexey Kuznetsov: new arp state machine; * now it is in net/core/neighbour.c. * Krzysztof Halasa: Added Frame Relay ARP support. * Arnaldo C. Melo : convert /proc/net/arp to seq_file * Shmulik Hen: Split arp_send to arp_create and * arp_xmit so intermediate drivers like * bonding can change the skb before * sending (e.g. insert 8021q tag). * Harald Welte : convert to make use of jenkins hash * Jesper D. Brouer: Proxy ARP PVLAN RFC 3069 support. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.h> #include <linux/types.h> #include <linux/string.h> #include <linux/kernel.h> #include <linux/capability.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/errno.h> #include <linux/in.h> #include <linux/mm.h> #include <linux/inet.h> #include <linux/inetdevice.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/fddidevice.h> #include <linux/if_arp.h> #include <linux/skbuff.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/stat.h> #include <linux/init.h> #include <linux/net.h> #include <linux/rcupdate.h> #include <linux/slab.h> #ifdef CONFIG_SYSCTL #include <linux/sysctl.h> #endif #include <net/net_namespace.h> #include <net/ip.h> #include <net/icmp.h> #include <net/route.h> #include <net/protocol.h> #include <net/tcp.h> #include <net/sock.h> #include <net/arp.h> #include <net/ax25.h> #include <net/netrom.h> #include <net/dst_metadata.h> #include <net/ip_tunnels.h> #include <linux/uaccess.h> #include <linux/netfilter_arp.h> /* * Interface to generic neighbour cache. */ static u32 arp_hash(const void *pkey, const struct net_device *dev, __u32 *hash_rnd); static bool arp_key_eq(const struct neighbour *n, const void *pkey); static int arp_constructor(struct neighbour *neigh); static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb); static void arp_error_report(struct neighbour *neigh, struct sk_buff *skb); static void parp_redo(struct sk_buff *skb); static int arp_is_multicast(const void *pkey); static const struct neigh_ops arp_generic_ops = { .family = AF_INET, .solicit = arp_solicit, .error_report = arp_error_report, .output = neigh_resolve_output, .connected_output = neigh_connected_output, }; static const struct neigh_ops arp_hh_ops = { .family = AF_INET, .solicit = arp_solicit, .error_report = arp_error_report, .output = neigh_resolve_output, .connected_output = neigh_resolve_output, }; static const struct neigh_ops arp_direct_ops = { .family = AF_INET, .output = neigh_direct_output, .connected_output = neigh_direct_output, }; struct neigh_table arp_tbl = { .family = AF_INET, .key_len = 4, .protocol = cpu_to_be16(ETH_P_IP), .hash = arp_hash, .key_eq = arp_key_eq, .constructor = arp_constructor, .proxy_redo = parp_redo, .is_multicast = arp_is_multicast, .id = "arp_cache", .parms = { .tbl = &arp_tbl, .reachable_time = 30 * HZ, .data = { [NEIGH_VAR_MCAST_PROBES] = 3, [NEIGH_VAR_UCAST_PROBES] = 3, [NEIGH_VAR_RETRANS_TIME] = 1 * HZ, [NEIGH_VAR_BASE_REACHABLE_TIME] = 30 * HZ, [NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ, [NEIGH_VAR_INTERVAL_PROBE_TIME_MS] = 5 * HZ, [NEIGH_VAR_GC_STALETIME] = 60 * HZ, [NEIGH_VAR_QUEUE_LEN_BYTES] = SK_WMEM_MAX, [NEIGH_VAR_PROXY_QLEN] = 64, [NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ, [NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10, [NEIGH_VAR_LOCKTIME] = 1 * HZ, }, }, .gc_interval = 30 * HZ, .gc_thresh1 = 128, .gc_thresh2 = 512, .gc_thresh3 = 1024, }; EXPORT_SYMBOL(arp_tbl); int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir) { switch (dev->type) { case ARPHRD_ETHER: case ARPHRD_FDDI: case ARPHRD_IEEE802: ip_eth_mc_map(addr, haddr); return 0; case ARPHRD_INFINIBAND: ip_ib_mc_map(addr, dev->broadcast, haddr); return 0; case ARPHRD_IPGRE: ip_ipgre_mc_map(addr, dev->broadcast, haddr); return 0; default: if (dir) { memcpy(haddr, dev->broadcast, dev->addr_len); return 0; } } return -EINVAL; } static u32 arp_hash(const void *pkey, const struct net_device *dev, __u32 *hash_rnd) { return arp_hashfn(pkey, dev, hash_rnd); } static bool arp_key_eq(const struct neighbour *neigh, const void *pkey) { return neigh_key_eq32(neigh, pkey); } static int arp_constructor(struct neighbour *neigh) { __be32 addr; struct net_device *dev = neigh->dev; struct in_device *in_dev; struct neigh_parms *parms; u32 inaddr_any = INADDR_ANY; if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) memcpy(neigh->primary_key, &inaddr_any, arp_tbl.key_len); addr = *(__be32 *)neigh->primary_key; rcu_read_lock(); in_dev = __in_dev_get_rcu(dev); if (!in_dev) { rcu_read_unlock(); return -EINVAL; } neigh->type = inet_addr_type_dev_table(dev_net(dev), dev, addr); parms = in_dev->arp_parms; __neigh_parms_put(neigh->parms); neigh->parms = neigh_parms_clone(parms); rcu_read_unlock(); if (!dev->header_ops) { neigh->nud_state = NUD_NOARP; neigh->ops = &arp_direct_ops; neigh->output = neigh_direct_output; } else { /* Good devices (checked by reading texts, but only Ethernet is tested) ARPHRD_ETHER: (ethernet, apfddi) ARPHRD_FDDI: (fddi) ARPHRD_IEEE802: (tr) ARPHRD_METRICOM: (strip) ARPHRD_ARCNET: etc. etc. etc. ARPHRD_IPDDP will also work, if author repairs it. I did not it, because this driver does not work even in old paradigm. */ if (neigh->type == RTN_MULTICAST) { neigh->nud_state = NUD_NOARP; arp_mc_map(addr, neigh->ha, dev, 1); } else if (dev->flags & (IFF_NOARP | IFF_LOOPBACK)) { neigh->nud_state = NUD_NOARP; memcpy(neigh->ha, dev->dev_addr, dev->addr_len); } else if (neigh->type == RTN_BROADCAST || (dev->flags & IFF_POINTOPOINT)) { neigh->nud_state = NUD_NOARP; memcpy(neigh->ha, dev->broadcast, dev->addr_len); } if (dev->header_ops->cache) neigh->ops = &arp_hh_ops; else neigh->ops = &arp_generic_ops; if (neigh->nud_state & NUD_VALID) neigh->output = neigh->ops->connected_output; else neigh->output = neigh->ops->output; } return 0; } static void arp_error_report(struct neighbour *neigh, struct sk_buff *skb) { dst_link_failure(skb); kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_FAILED); } /* Create and send an arp packet. */ static void arp_send_dst(int type, int ptype, __be32 dest_ip, struct net_device *dev, __be32 src_ip, const unsigned char *dest_hw, const unsigned char *src_hw, const unsigned char *target_hw, struct dst_entry *dst) { struct sk_buff *skb; /* arp on this interface. */ if (dev->flags & IFF_NOARP) return; skb = arp_create(type, ptype, dest_ip, dev, src_ip, dest_hw, src_hw, target_hw); if (!skb) return; skb_dst_set(skb, dst_clone(dst)); arp_xmit(skb); } void arp_send(int type, int ptype, __be32 dest_ip, struct net_device *dev, __be32 src_ip, const unsigned char *dest_hw, const unsigned char *src_hw, const unsigned char *target_hw) { arp_send_dst(type, ptype, dest_ip, dev, src_ip, dest_hw, src_hw, target_hw, NULL); } EXPORT_SYMBOL(arp_send); static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb) { __be32 saddr = 0; u8 dst_ha[MAX_ADDR_LEN], *dst_hw = NULL; struct net_device *dev = neigh->dev; __be32 target = *(__be32 *)neigh->primary_key; int probes = atomic_read(&neigh->probes); struct in_device *in_dev; struct dst_entry *dst = NULL; rcu_read_lock(); in_dev = __in_dev_get_rcu(dev); if (!in_dev) { rcu_read_unlock(); return; } switch (IN_DEV_ARP_ANNOUNCE(in_dev)) { default: case 0: /* By default announce any local IP */ if (skb && inet_addr_type_dev_table(dev_net(dev), dev, ip_hdr(skb)->saddr) == RTN_LOCAL) saddr = ip_hdr(skb)->saddr; break; case 1: /* Restrict announcements of saddr in same subnet */ if (!skb) break; saddr = ip_hdr(skb)->saddr; if (inet_addr_type_dev_table(dev_net(dev), dev, saddr) == RTN_LOCAL) { /* saddr should be known to target */ if (inet_addr_onlink(in_dev, target, saddr)) break; } saddr = 0; break; case 2: /* Avoid secondary IPs, get a primary/preferred one */ break; } rcu_read_unlock(); if (!saddr) saddr = inet_select_addr(dev, target, RT_SCOPE_LINK); probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES); if (probes < 0) { if (!(READ_ONCE(neigh->nud_state) & NUD_VALID)) pr_debug("trying to ucast probe in NUD_INVALID\n"); neigh_ha_snapshot(dst_ha, neigh, dev); dst_hw = dst_ha; } else { probes -= NEIGH_VAR(neigh->parms, APP_PROBES); if (probes < 0) { neigh_app_ns(neigh); return; } } if (skb && !(dev->priv_flags & IFF_XMIT_DST_RELEASE)) dst = skb_dst(skb); arp_send_dst(ARPOP_REQUEST, ETH_P_ARP, target, dev, saddr, dst_hw, dev->dev_addr, NULL, dst); } static int arp_ignore(struct in_device *in_dev, __be32 sip, __be32 tip) { struct net *net = dev_net(in_dev->dev); int scope; switch (IN_DEV_ARP_IGNORE(in_dev)) { case 0: /* Reply, the tip is already validated */ return 0; case 1: /* Reply only if tip is configured on the incoming interface */ sip = 0; scope = RT_SCOPE_HOST; break; case 2: /* * Reply only if tip is configured on the incoming interface * and is in same subnet as sip */ scope = RT_SCOPE_HOST; break; case 3: /* Do not reply for scope host addresses */ sip = 0; scope = RT_SCOPE_LINK; in_dev = NULL; break; case 4: /* Reserved */ case 5: case 6: case 7: return 0; case 8: /* Do not reply */ return 1; default: return 0; } return !inet_confirm_addr(net, in_dev, sip, tip, scope); } static int arp_accept(struct in_device *in_dev, __be32 sip) { struct net *net = dev_net(in_dev->dev); int scope = RT_SCOPE_LINK; switch (IN_DEV_ARP_ACCEPT(in_dev)) { case 0: /* Don't create new entries from garp */ return 0; case 1: /* Create new entries from garp */ return 1; case 2: /* Create a neighbor in the arp table only if sip * is in the same subnet as an address configured * on the interface that received the garp message */ return !!inet_confirm_addr(net, in_dev, sip, 0, scope); default: return 0; } } static int arp_filter(__be32 sip, __be32 tip, struct net_device *dev) { struct rtable *rt; int flag = 0; /*unsigned long now; */ struct net *net = dev_net(dev); rt = ip_route_output(net, sip, tip, 0, l3mdev_master_ifindex_rcu(dev)); if (IS_ERR(rt)) return 1; if (rt->dst.dev != dev) { __NET_INC_STATS(net, LINUX_MIB_ARPFILTER); flag = 1; } ip_rt_put(rt); return flag; } /* * Check if we can use proxy ARP for this path */ static inline int arp_fwd_proxy(struct in_device *in_dev, struct net_device *dev, struct rtable *rt) { struct in_device *out_dev; int imi, omi = -1; if (rt->dst.dev == dev) return 0; if (!IN_DEV_PROXY_ARP(in_dev)) return 0; imi = IN_DEV_MEDIUM_ID(in_dev); if (imi == 0) return 1; if (imi == -1) return 0; /* place to check for proxy_arp for routes */ out_dev = __in_dev_get_rcu(rt->dst.dev); if (out_dev) omi = IN_DEV_MEDIUM_ID(out_dev); return omi != imi && omi != -1; } /* * Check for RFC3069 proxy arp private VLAN (allow to send back to same dev) * * RFC3069 supports proxy arp replies back to the same interface. This * is done to support (ethernet) switch features, like RFC 3069, where * the individual ports are not allowed to communicate with each * other, BUT they are allowed to talk to the upstream router. As * described in RFC 3069, it is possible to allow these hosts to * communicate through the upstream router, by proxy_arp'ing. * * RFC 3069: "VLAN Aggregation for Efficient IP Address Allocation" * * This technology is known by different names: * In RFC 3069 it is called VLAN Aggregation. * Cisco and Allied Telesyn call it Private VLAN. * Hewlett-Packard call it Source-Port filtering or port-isolation. * Ericsson call it MAC-Forced Forwarding (RFC Draft). * */ static inline int arp_fwd_pvlan(struct in_device *in_dev, struct net_device *dev, struct rtable *rt, __be32 sip, __be32 tip) { /* Private VLAN is only concerned about the same ethernet segment */ if (rt->dst.dev != dev) return 0; /* Don't reply on self probes (often done by windowz boxes)*/ if (sip == tip) return 0; if (IN_DEV_PROXY_ARP_PVLAN(in_dev)) return 1; else return 0; } /* * Interface to link layer: send routine and receive handler. */ /* * Create an arp packet. If dest_hw is not set, we create a broadcast * message. */ struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip, struct net_device *dev, __be32 src_ip, const unsigned char *dest_hw, const unsigned char *src_hw, const unsigned char *target_hw) { struct sk_buff *skb; struct arphdr *arp; unsigned char *arp_ptr; int hlen = LL_RESERVED_SPACE(dev); int tlen = dev->needed_tailroom; /* * Allocate a buffer */ skb = alloc_skb(arp_hdr_len(dev) + hlen + tlen, GFP_ATOMIC); if (!skb) return NULL; skb_reserve(skb, hlen); skb_reset_network_header(skb); arp = skb_put(skb, arp_hdr_len(dev)); skb->dev = dev; skb->protocol = htons(ETH_P_ARP); if (!src_hw) src_hw = dev->dev_addr; if (!dest_hw) dest_hw = dev->broadcast; /* * Fill the device header for the ARP frame */ if (dev_hard_header(skb, dev, ptype, dest_hw, src_hw, skb->len) < 0) goto out; /* * Fill out the arp protocol part. * * The arp hardware type should match the device type, except for FDDI, * which (according to RFC 1390) should always equal 1 (Ethernet). */ /* * Exceptions everywhere. AX.25 uses the AX.25 PID value not the * DIX code for the protocol. Make these device structure fields. */ switch (dev->type) { default: arp->ar_hrd = htons(dev->type); arp->ar_pro = htons(ETH_P_IP); break; #if IS_ENABLED(CONFIG_AX25) case ARPHRD_AX25: arp->ar_hrd = htons(ARPHRD_AX25); arp->ar_pro = htons(AX25_P_IP); break; #if IS_ENABLED(CONFIG_NETROM) case ARPHRD_NETROM: arp->ar_hrd = htons(ARPHRD_NETROM); arp->ar_pro = htons(AX25_P_IP); break; #endif #endif #if IS_ENABLED(CONFIG_FDDI) case ARPHRD_FDDI: arp->ar_hrd = htons(ARPHRD_ETHER); arp->ar_pro = htons(ETH_P_IP); break; #endif } arp->ar_hln = dev->addr_len; arp->ar_pln = 4; arp->ar_op = htons(type); arp_ptr = (unsigned char *)(arp + 1); memcpy(arp_ptr, src_hw, dev->addr_len); arp_ptr += dev->addr_len; memcpy(arp_ptr, &src_ip, 4); arp_ptr += 4; switch (dev->type) { #if IS_ENABLED(CONFIG_FIREWIRE_NET) case ARPHRD_IEEE1394: break; #endif default: if (target_hw) memcpy(arp_ptr, target_hw, dev->addr_len); else memset(arp_ptr, 0, dev->addr_len); arp_ptr += dev->addr_len; } memcpy(arp_ptr, &dest_ip, 4); return skb; out: kfree_skb(skb); return NULL; } EXPORT_SYMBOL(arp_create); static int arp_xmit_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { return dev_queue_xmit(skb); } /* * Send an arp packet. */ void arp_xmit(struct sk_buff *skb) { /* Send it off, maybe filter it using firewalling first. */ NF_HOOK(NFPROTO_ARP, NF_ARP_OUT, dev_net(skb->dev), NULL, skb, NULL, skb->dev, arp_xmit_finish); } EXPORT_SYMBOL(arp_xmit); static bool arp_is_garp(struct net *net, struct net_device *dev, int *addr_type, __be16 ar_op, __be32 sip, __be32 tip, unsigned char *sha, unsigned char *tha) { bool is_garp = tip == sip; /* Gratuitous ARP _replies_ also require target hwaddr to be * the same as source. */ if (is_garp && ar_op == htons(ARPOP_REPLY)) is_garp = /* IPv4 over IEEE 1394 doesn't provide target * hardware address field in its ARP payload. */ tha && !memcmp(tha, sha, dev->addr_len); if (is_garp) { *addr_type = inet_addr_type_dev_table(net, dev, sip); if (*addr_type != RTN_UNICAST) is_garp = false; } return is_garp; } /* * Process an arp request. */ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) { struct net_device *dev = skb->dev; struct in_device *in_dev = __in_dev_get_rcu(dev); struct arphdr *arp; unsigned char *arp_ptr; struct rtable *rt; unsigned char *sha; unsigned char *tha = NULL; __be32 sip, tip; u16 dev_type = dev->type; int addr_type; struct neighbour *n; struct dst_entry *reply_dst = NULL; bool is_garp = false; /* arp_rcv below verifies the ARP header and verifies the device * is ARP'able. */ if (!in_dev) goto out_free_skb; arp = arp_hdr(skb); switch (dev_type) { default: if (arp->ar_pro != htons(ETH_P_IP) || htons(dev_type) != arp->ar_hrd) goto out_free_skb; break; case ARPHRD_ETHER: case ARPHRD_FDDI: case ARPHRD_IEEE802: /* * ETHERNET, and Fibre Channel (which are IEEE 802 * devices, according to RFC 2625) devices will accept ARP * hardware types of either 1 (Ethernet) or 6 (IEEE 802.2). * This is the case also of FDDI, where the RFC 1390 says that * FDDI devices should accept ARP hardware of (1) Ethernet, * however, to be more robust, we'll accept both 1 (Ethernet) * or 6 (IEEE 802.2) */ if ((arp->ar_hrd != htons(ARPHRD_ETHER) && arp->ar_hrd != htons(ARPHRD_IEEE802)) || arp->ar_pro != htons(ETH_P_IP)) goto out_free_skb; break; case ARPHRD_AX25: if (arp->ar_pro != htons(AX25_P_IP) || arp->ar_hrd != htons(ARPHRD_AX25)) goto out_free_skb; break; case ARPHRD_NETROM: if (arp->ar_pro != htons(AX25_P_IP) || arp->ar_hrd != htons(ARPHRD_NETROM)) goto out_free_skb; break; } /* Understand only these message types */ if (arp->ar_op != htons(ARPOP_REPLY) && arp->ar_op != htons(ARPOP_REQUEST)) goto out_free_skb; /* * Extract fields */ arp_ptr = (unsigned char *)(arp + 1); sha = arp_ptr; arp_ptr += dev->addr_len; memcpy(&sip, arp_ptr, 4); arp_ptr += 4; switch (dev_type) { #if IS_ENABLED(CONFIG_FIREWIRE_NET) case ARPHRD_IEEE1394: break; #endif default: tha = arp_ptr; arp_ptr += dev->addr_len; } memcpy(&tip, arp_ptr, 4); /* * Check for bad requests for 127.x.x.x and requests for multicast * addresses. If this is one such, delete it. */ if (ipv4_is_multicast(tip) || (!IN_DEV_ROUTE_LOCALNET(in_dev) && ipv4_is_loopback(tip))) goto out_free_skb; /* * For some 802.11 wireless deployments (and possibly other networks), * there will be an ARP proxy and gratuitous ARP frames are attacks * and thus should not be accepted. */ if (sip == tip && IN_DEV_ORCONF(in_dev, DROP_GRATUITOUS_ARP)) goto out_free_skb; /* * Special case: We must set Frame Relay source Q.922 address */ if (dev_type == ARPHRD_DLCI) sha = dev->broadcast; /* * Process entry. The idea here is we want to send a reply if it is a * request for us or if it is a request for someone else that we hold * a proxy for. We want to add an entry to our cache if it is a reply * to us or if it is a request for our address. * (The assumption for this last is that if someone is requesting our * address, they are probably intending to talk to us, so it saves time * if we cache their address. Their address is also probably not in * our cache, since ours is not in their cache.) * * Putting this another way, we only care about replies if they are to * us, in which case we add them to the cache. For requests, we care * about those for us and those for our proxies. We reply to both, * and in the case of requests for us we add the requester to the arp * cache. */ if (arp->ar_op == htons(ARPOP_REQUEST) && skb_metadata_dst(skb)) reply_dst = (struct dst_entry *) iptunnel_metadata_reply(skb_metadata_dst(skb), GFP_ATOMIC); /* Special case: IPv4 duplicate address detection packet (RFC2131) */ if (sip == 0) { if (arp->ar_op == htons(ARPOP_REQUEST) && inet_addr_type_dev_table(net, dev, tip) == RTN_LOCAL && !arp_ignore(in_dev, sip, tip)) arp_send_dst(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha, dev->dev_addr, sha, reply_dst); goto out_consume_skb; } if (arp->ar_op == htons(ARPOP_REQUEST) && ip_route_input_noref(skb, tip, sip, 0, dev) == 0) { rt = skb_rtable(skb); addr_type = rt->rt_type; if (addr_type == RTN_LOCAL) { int dont_send; dont_send = arp_ignore(in_dev, sip, tip); if (!dont_send && IN_DEV_ARPFILTER(in_dev)) dont_send = arp_filter(sip, tip, dev); if (!dont_send) { n = neigh_event_ns(&arp_tbl, sha, &sip, dev); if (n) { arp_send_dst(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha, dev->dev_addr, sha, reply_dst); neigh_release(n); } } goto out_consume_skb; } else if (IN_DEV_FORWARD(in_dev)) { if (addr_type == RTN_UNICAST && (arp_fwd_proxy(in_dev, dev, rt) || arp_fwd_pvlan(in_dev, dev, rt, sip, tip) || (rt->dst.dev != dev && pneigh_lookup(&arp_tbl, net, &tip, dev, 0)))) { n = neigh_event_ns(&arp_tbl, sha, &sip, dev); if (n) neigh_release(n); if (NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED || skb->pkt_type == PACKET_HOST || NEIGH_VAR(in_dev->arp_parms, PROXY_DELAY) == 0) { arp_send_dst(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha, dev->dev_addr, sha, reply_dst); } else { pneigh_enqueue(&arp_tbl, in_dev->arp_parms, skb); goto out_free_dst; } goto out_consume_skb; } } } /* Update our ARP tables */ n = __neigh_lookup(&arp_tbl, &sip, dev, 0); addr_type = -1; if (n || arp_accept(in_dev, sip)) { is_garp = arp_is_garp(net, dev, &addr_type, arp->ar_op, sip, tip, sha, tha); } if (arp_accept(in_dev, sip)) { /* Unsolicited ARP is not accepted by default. It is possible, that this option should be enabled for some devices (strip is candidate) */ if (!n && (is_garp || (arp->ar_op == htons(ARPOP_REPLY) && (addr_type == RTN_UNICAST || (addr_type < 0 && /* postpone calculation to as late as possible */ inet_addr_type_dev_table(net, dev, sip) == RTN_UNICAST))))) n = __neigh_lookup(&arp_tbl, &sip, dev, 1); } if (n) { int state = NUD_REACHABLE; int override; /* If several different ARP replies follows back-to-back, use the FIRST one. It is possible, if several proxy agents are active. Taking the first reply prevents arp trashing and chooses the fastest router. */ override = time_after(jiffies, n->updated + NEIGH_VAR(n->parms, LOCKTIME)) || is_garp; /* Broadcast replies and request packets do not assert neighbour reachability. */ if (arp->ar_op != htons(ARPOP_REPLY) || skb->pkt_type != PACKET_HOST) state = NUD_STALE; neigh_update(n, sha, state, override ? NEIGH_UPDATE_F_OVERRIDE : 0, 0); neigh_release(n); } out_consume_skb: consume_skb(skb); out_free_dst: dst_release(reply_dst); return NET_RX_SUCCESS; out_free_skb: kfree_skb(skb); return NET_RX_DROP; } static void parp_redo(struct sk_buff *skb) { arp_process(dev_net(skb->dev), NULL, skb); } static int arp_is_multicast(const void *pkey) { return ipv4_is_multicast(*((__be32 *)pkey)); } /* * Receive an arp request from the device layer. */ static int arp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { const struct arphdr *arp; /* do not tweak dropwatch on an ARP we will ignore */ if (dev->flags & IFF_NOARP || skb->pkt_type == PACKET_OTHERHOST || skb->pkt_type == PACKET_LOOPBACK) goto consumeskb; skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) goto out_of_mem; /* ARP header, plus 2 device addresses, plus 2 IP addresses. */ if (!pskb_may_pull(skb, arp_hdr_len(dev))) goto freeskb; arp = arp_hdr(skb); if (arp->ar_hln != dev->addr_len || arp->ar_pln != 4) goto freeskb; memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb)); return NF_HOOK(NFPROTO_ARP, NF_ARP_IN, dev_net(dev), NULL, skb, dev, NULL, arp_process); consumeskb: consume_skb(skb); return NET_RX_SUCCESS; freeskb: kfree_skb(skb); out_of_mem: return NET_RX_DROP; } /* * User level interface (ioctl) */ /* * Set (create) an ARP cache entry. */ static int arp_req_set_proxy(struct net *net, struct net_device *dev, int on) { if (!dev) { IPV4_DEVCONF_ALL(net, PROXY_ARP) = on; return 0; } if (__in_dev_get_rtnl(dev)) { IN_DEV_CONF_SET(__in_dev_get_rtnl(dev), PROXY_ARP, on); return 0; } return -ENXIO; } static int arp_req_set_public(struct net *net, struct arpreq *r, struct net_device *dev) { __be32 ip = ((struct sockaddr_in *)&r->arp_pa)->sin_addr.s_addr; __be32 mask = ((struct sockaddr_in *)&r->arp_netmask)->sin_addr.s_addr; if (mask && mask != htonl(0xFFFFFFFF)) return -EINVAL; if (!dev && (r->arp_flags & ATF_COM)) { dev = dev_getbyhwaddr_rcu(net, r->arp_ha.sa_family, r->arp_ha.sa_data); if (!dev) return -ENODEV; } if (mask) { if (!pneigh_lookup(&arp_tbl, net, &ip, dev, 1)) return -ENOBUFS; return 0; } return arp_req_set_proxy(net, dev, 1); } static int arp_req_set(struct net *net, struct arpreq *r, struct net_device *dev) { __be32 ip; struct neighbour *neigh; int err; if (r->arp_flags & ATF_PUBL) return arp_req_set_public(net, r, dev); ip = ((struct sockaddr_in *)&r->arp_pa)->sin_addr.s_addr; if (r->arp_flags & ATF_PERM) r->arp_flags |= ATF_COM; if (!dev) { struct rtable *rt = ip_route_output(net, ip, 0, RTO_ONLINK, 0); if (IS_ERR(rt)) return PTR_ERR(rt); dev = rt->dst.dev; ip_rt_put(rt); if (!dev) return -EINVAL; } switch (dev->type) { #if IS_ENABLED(CONFIG_FDDI) case ARPHRD_FDDI: /* * According to RFC 1390, FDDI devices should accept ARP * hardware types of 1 (Ethernet). However, to be more * robust, we'll accept hardware types of either 1 (Ethernet) * or 6 (IEEE 802.2). */ if (r->arp_ha.sa_family != ARPHRD_FDDI && r->arp_ha.sa_family != ARPHRD_ETHER && r->arp_ha.sa_family != ARPHRD_IEEE802) return -EINVAL; break; #endif default: if (r->arp_ha.sa_family != dev->type) return -EINVAL; break; } neigh = __neigh_lookup_errno(&arp_tbl, &ip, dev); err = PTR_ERR(neigh); if (!IS_ERR(neigh)) { unsigned int state = NUD_STALE; if (r->arp_flags & ATF_PERM) state = NUD_PERMANENT; err = neigh_update(neigh, (r->arp_flags & ATF_COM) ? r->arp_ha.sa_data : NULL, state, NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN, 0); neigh_release(neigh); } return err; } static unsigned int arp_state_to_flags(struct neighbour *neigh) { if (neigh->nud_state&NUD_PERMANENT) return ATF_PERM | ATF_COM; else if (neigh->nud_state&NUD_VALID) return ATF_COM; else return 0; } /* * Get an ARP cache entry. */ static int arp_req_get(struct arpreq *r, struct net_device *dev) { __be32 ip = ((struct sockaddr_in *) &r->arp_pa)->sin_addr.s_addr; struct neighbour *neigh; int err = -ENXIO; neigh = neigh_lookup(&arp_tbl, &ip, dev); if (neigh) { if (!(READ_ONCE(neigh->nud_state) & NUD_NOARP)) { read_lock_bh(&neigh->lock); memcpy(r->arp_ha.sa_data, neigh->ha, dev->addr_len); r->arp_flags = arp_state_to_flags(neigh); read_unlock_bh(&neigh->lock); r->arp_ha.sa_family = dev->type; strscpy(r->arp_dev, dev->name, sizeof(r->arp_dev)); err = 0; } neigh_release(neigh); } return err; } int arp_invalidate(struct net_device *dev, __be32 ip, bool force) { struct neighbour *neigh = neigh_lookup(&arp_tbl, &ip, dev); int err = -ENXIO; struct neigh_table *tbl = &arp_tbl; if (neigh) { if ((READ_ONCE(neigh->nud_state) & NUD_VALID) && !force) { neigh_release(neigh); return 0; } if (READ_ONCE(neigh->nud_state) & ~NUD_NOARP) err = neigh_update(neigh, NULL, NUD_FAILED, NEIGH_UPDATE_F_OVERRIDE| NEIGH_UPDATE_F_ADMIN, 0); write_lock_bh(&tbl->lock); neigh_release(neigh); neigh_remove_one(neigh, tbl); write_unlock_bh(&tbl->lock); } return err; } static int arp_req_delete_public(struct net *net, struct arpreq *r, struct net_device *dev) { __be32 ip = ((struct sockaddr_in *) &r->arp_pa)->sin_addr.s_addr; __be32 mask = ((struct sockaddr_in *)&r->arp_netmask)->sin_addr.s_addr; if (mask == htonl(0xFFFFFFFF)) return pneigh_delete(&arp_tbl, net, &ip, dev); if (mask) return -EINVAL; return arp_req_set_proxy(net, dev, 0); } static int arp_req_delete(struct net *net, struct arpreq *r, struct net_device *dev) { __be32 ip; if (r->arp_flags & ATF_PUBL) return arp_req_delete_public(net, r, dev); ip = ((struct sockaddr_in *)&r->arp_pa)->sin_addr.s_addr; if (!dev) { struct rtable *rt = ip_route_output(net, ip, 0, RTO_ONLINK, 0); if (IS_ERR(rt)) return PTR_ERR(rt); dev = rt->dst.dev; ip_rt_put(rt); if (!dev) return -EINVAL; } return arp_invalidate(dev, ip, true); } /* * Handle an ARP layer I/O control request. */ int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg) { int err; struct arpreq r; struct net_device *dev = NULL; switch (cmd) { case SIOCDARP: case SIOCSARP: if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) return -EPERM; fallthrough; case SIOCGARP: err = copy_from_user(&r, arg, sizeof(struct arpreq)); if (err) return -EFAULT; break; default: return -EINVAL; } if (r.arp_pa.sa_family != AF_INET) return -EPFNOSUPPORT; if (!(r.arp_flags & ATF_PUBL) && (r.arp_flags & (ATF_NETMASK | ATF_DONTPUB))) return -EINVAL; if (!(r.arp_flags & ATF_NETMASK)) ((struct sockaddr_in *)&r.arp_netmask)->sin_addr.s_addr = htonl(0xFFFFFFFFUL); rtnl_lock(); if (r.arp_dev[0]) { err = -ENODEV; dev = __dev_get_by_name(net, r.arp_dev); if (!dev) goto out; /* Mmmm... It is wrong... ARPHRD_NETROM==0 */ if (!r.arp_ha.sa_family) r.arp_ha.sa_family = dev->type; err = -EINVAL; if ((r.arp_flags & ATF_COM) && r.arp_ha.sa_family != dev->type) goto out; } else if (cmd == SIOCGARP) { err = -ENODEV; goto out; } switch (cmd) { case SIOCDARP: err = arp_req_delete(net, &r, dev); break; case SIOCSARP: err = arp_req_set(net, &r, dev); break; case SIOCGARP: err = arp_req_get(&r, dev); break; } out: rtnl_unlock(); if (cmd == SIOCGARP && !err && copy_to_user(arg, &r, sizeof(r))) err = -EFAULT; return err; } static int arp_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct netdev_notifier_change_info *change_info; struct in_device *in_dev; bool evict_nocarrier; switch (event) { case NETDEV_CHANGEADDR: neigh_changeaddr(&arp_tbl, dev); rt_cache_flush(dev_net(dev)); break; case NETDEV_CHANGE: change_info = ptr; if (change_info->flags_changed & IFF_NOARP) neigh_changeaddr(&arp_tbl, dev); in_dev = __in_dev_get_rtnl(dev); if (!in_dev) evict_nocarrier = true; else evict_nocarrier = IN_DEV_ARP_EVICT_NOCARRIER(in_dev); if (evict_nocarrier && !netif_carrier_ok(dev)) neigh_carrier_down(&arp_tbl, dev); break; default: break; } return NOTIFY_DONE; } static struct notifier_block arp_netdev_notifier = { .notifier_call = arp_netdev_event, }; /* Note, that it is not on notifier chain. It is necessary, that this routine was called after route cache will be flushed. */ void arp_ifdown(struct net_device *dev) { neigh_ifdown(&arp_tbl, dev); } /* * Called once on startup. */ static struct packet_type arp_packet_type __read_mostly = { .type = cpu_to_be16(ETH_P_ARP), .func = arp_rcv, }; #ifdef CONFIG_PROC_FS #if IS_ENABLED(CONFIG_AX25) /* * ax25 -> ASCII conversion */ static void ax2asc2(ax25_address *a, char *buf) { char c, *s; int n; for (n = 0, s = buf; n < 6; n++) { c = (a->ax25_call[n] >> 1) & 0x7F; if (c != ' ') *s++ = c; } *s++ = '-'; n = (a->ax25_call[6] >> 1) & 0x0F; if (n > 9) { *s++ = '1'; n -= 10; } *s++ = n + '0'; *s++ = '\0'; if (*buf == '\0' || *buf == '-') { buf[0] = '*'; buf[1] = '\0'; } } #endif /* CONFIG_AX25 */ #define HBUFFERLEN 30 static void arp_format_neigh_entry(struct seq_file *seq, struct neighbour *n) { char hbuffer[HBUFFERLEN]; int k, j; char tbuf[16]; struct net_device *dev = n->dev; int hatype = dev->type; read_lock(&n->lock); /* Convert hardware address to XX:XX:XX:XX ... form. */ #if IS_ENABLED(CONFIG_AX25) if (hatype == ARPHRD_AX25 || hatype == ARPHRD_NETROM) ax2asc2((ax25_address *)n->ha, hbuffer); else { #endif for (k = 0, j = 0; k < HBUFFERLEN - 3 && j < dev->addr_len; j++) { hbuffer[k++] = hex_asc_hi(n->ha[j]); hbuffer[k++] = hex_asc_lo(n->ha[j]); hbuffer[k++] = ':'; } if (k != 0) --k; hbuffer[k] = 0; #if IS_ENABLED(CONFIG_AX25) } #endif sprintf(tbuf, "%pI4", n->primary_key); seq_printf(seq, "%-16s 0x%-10x0x%-10x%-17s * %s\n", tbuf, hatype, arp_state_to_flags(n), hbuffer, dev->name); read_unlock(&n->lock); } static void arp_format_pneigh_entry(struct seq_file *seq, struct pneigh_entry *n) { struct net_device *dev = n->dev; int hatype = dev ? dev->type : 0; char tbuf[16]; sprintf(tbuf, "%pI4", n->key); seq_printf(seq, "%-16s 0x%-10x0x%-10x%s * %s\n", tbuf, hatype, ATF_PUBL | ATF_PERM, "00:00:00:00:00:00", dev ? dev->name : "*"); } static int arp_seq_show(struct seq_file *seq, void *v) { if (v == SEQ_START_TOKEN) { seq_puts(seq, "IP address HW type Flags " "HW address Mask Device\n"); } else { struct neigh_seq_state *state = seq->private; if (state->flags & NEIGH_SEQ_IS_PNEIGH) arp_format_pneigh_entry(seq, v); else arp_format_neigh_entry(seq, v); } return 0; } static void *arp_seq_start(struct seq_file *seq, loff_t *pos) { /* Don't want to confuse "arp -a" w/ magic entries, * so we tell the generic iterator to skip NUD_NOARP. */ return neigh_seq_start(seq, pos, &arp_tbl, NEIGH_SEQ_SKIP_NOARP); } static const struct seq_operations arp_seq_ops = { .start = arp_seq_start, .next = neigh_seq_next, .stop = neigh_seq_stop, .show = arp_seq_show, }; #endif /* CONFIG_PROC_FS */ static int __net_init arp_net_init(struct net *net) { if (!proc_create_net("arp", 0444, net->proc_net, &arp_seq_ops, sizeof(struct neigh_seq_state))) return -ENOMEM; return 0; } static void __net_exit arp_net_exit(struct net *net) { remove_proc_entry("arp", net->proc_net); } static struct pernet_operations arp_net_ops = { .init = arp_net_init, .exit = arp_net_exit, }; void __init arp_init(void) { neigh_table_init(NEIGH_ARP_TABLE, &arp_tbl); dev_add_pack(&arp_packet_type); register_pernet_subsys(&arp_net_ops); #ifdef CONFIG_SYSCTL neigh_sysctl_register(NULL, &arp_tbl.parms, NULL); #endif register_netdevice_notifier(&arp_netdev_notifier); }
linux-master
net/ipv4/arp.c
// SPDX-License-Identifier: GPL-2.0-only #define pr_fmt(fmt) "IPsec: " fmt #include <crypto/aead.h> #include <crypto/authenc.h> #include <linux/err.h> #include <linux/module.h> #include <net/ip.h> #include <net/xfrm.h> #include <net/esp.h> #include <linux/scatterlist.h> #include <linux/kernel.h> #include <linux/pfkeyv2.h> #include <linux/rtnetlink.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/in6.h> #include <net/icmp.h> #include <net/protocol.h> #include <net/udp.h> #include <net/tcp.h> #include <net/espintcp.h> #include <linux/highmem.h> struct esp_skb_cb { struct xfrm_skb_cb xfrm; void *tmp; }; struct esp_output_extra { __be32 seqhi; u32 esphoff; }; #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) /* * Allocate an AEAD request structure with extra space for SG and IV. * * For alignment considerations the IV is placed at the front, followed * by the request and finally the SG list. * * TODO: Use spare space in skb for this where possible. */ static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int extralen) { unsigned int len; len = extralen; len += crypto_aead_ivsize(aead); if (len) { len += crypto_aead_alignmask(aead) & ~(crypto_tfm_ctx_alignment() - 1); len = ALIGN(len, crypto_tfm_ctx_alignment()); } len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); len = ALIGN(len, __alignof__(struct scatterlist)); len += sizeof(struct scatterlist) * nfrags; return kmalloc(len, GFP_ATOMIC); } static inline void *esp_tmp_extra(void *tmp) { return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra)); } static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int extralen) { return crypto_aead_ivsize(aead) ? PTR_ALIGN((u8 *)tmp + extralen, crypto_aead_alignmask(aead) + 1) : tmp + extralen; } static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) { struct aead_request *req; req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), crypto_tfm_ctx_alignment()); aead_request_set_tfm(req, aead); return req; } static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, struct aead_request *req) { return (void *)ALIGN((unsigned long)(req + 1) + crypto_aead_reqsize(aead), __alignof__(struct scatterlist)); } static void esp_ssg_unref(struct xfrm_state *x, void *tmp) { struct crypto_aead *aead = x->data; int extralen = 0; u8 *iv; struct aead_request *req; struct scatterlist *sg; if (x->props.flags & XFRM_STATE_ESN) extralen += sizeof(struct esp_output_extra); iv = esp_tmp_iv(aead, tmp, extralen); req = esp_tmp_req(aead, iv); /* Unref skb_frag_pages in the src scatterlist if necessary. * Skip the first sg which comes from skb->data. */ if (req->src != req->dst) for (sg = sg_next(req->src); sg; sg = sg_next(sg)) put_page(sg_page(sg)); } #ifdef CONFIG_INET_ESPINTCP struct esp_tcp_sk { struct sock *sk; struct rcu_head rcu; }; static void esp_free_tcp_sk(struct rcu_head *head) { struct esp_tcp_sk *esk = container_of(head, struct esp_tcp_sk, rcu); sock_put(esk->sk); kfree(esk); } static struct sock *esp_find_tcp_sk(struct xfrm_state *x) { struct xfrm_encap_tmpl *encap = x->encap; struct net *net = xs_net(x); struct esp_tcp_sk *esk; __be16 sport, dport; struct sock *nsk; struct sock *sk; sk = rcu_dereference(x->encap_sk); if (sk && sk->sk_state == TCP_ESTABLISHED) return sk; spin_lock_bh(&x->lock); sport = encap->encap_sport; dport = encap->encap_dport; nsk = rcu_dereference_protected(x->encap_sk, lockdep_is_held(&x->lock)); if (sk && sk == nsk) { esk = kmalloc(sizeof(*esk), GFP_ATOMIC); if (!esk) { spin_unlock_bh(&x->lock); return ERR_PTR(-ENOMEM); } RCU_INIT_POINTER(x->encap_sk, NULL); esk->sk = sk; call_rcu(&esk->rcu, esp_free_tcp_sk); } spin_unlock_bh(&x->lock); sk = inet_lookup_established(net, net->ipv4.tcp_death_row.hashinfo, x->id.daddr.a4, dport, x->props.saddr.a4, sport, 0); if (!sk) return ERR_PTR(-ENOENT); if (!tcp_is_ulp_esp(sk)) { sock_put(sk); return ERR_PTR(-EINVAL); } spin_lock_bh(&x->lock); nsk = rcu_dereference_protected(x->encap_sk, lockdep_is_held(&x->lock)); if (encap->encap_sport != sport || encap->encap_dport != dport) { sock_put(sk); sk = nsk ?: ERR_PTR(-EREMCHG); } else if (sk == nsk) { sock_put(sk); } else { rcu_assign_pointer(x->encap_sk, sk); } spin_unlock_bh(&x->lock); return sk; } static int esp_output_tcp_finish(struct xfrm_state *x, struct sk_buff *skb) { struct sock *sk; int err; rcu_read_lock(); sk = esp_find_tcp_sk(x); err = PTR_ERR_OR_ZERO(sk); if (err) goto out; bh_lock_sock(sk); if (sock_owned_by_user(sk)) err = espintcp_queue_out(sk, skb); else err = espintcp_push_skb(sk, skb); bh_unlock_sock(sk); out: rcu_read_unlock(); return err; } static int esp_output_tcp_encap_cb(struct net *net, struct sock *sk, struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); struct xfrm_state *x = dst->xfrm; return esp_output_tcp_finish(x, skb); } static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb) { int err; local_bh_disable(); err = xfrm_trans_queue_net(xs_net(x), skb, esp_output_tcp_encap_cb); local_bh_enable(); /* EINPROGRESS just happens to do the right thing. It * actually means that the skb has been consumed and * isn't coming back. */ return err ?: -EINPROGRESS; } #else static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb) { kfree_skb(skb); return -EOPNOTSUPP; } #endif static void esp_output_done(void *data, int err) { struct sk_buff *skb = data; struct xfrm_offload *xo = xfrm_offload(skb); void *tmp; struct xfrm_state *x; if (xo && (xo->flags & XFRM_DEV_RESUME)) { struct sec_path *sp = skb_sec_path(skb); x = sp->xvec[sp->len - 1]; } else { x = skb_dst(skb)->xfrm; } tmp = ESP_SKB_CB(skb)->tmp; esp_ssg_unref(x, tmp); kfree(tmp); if (xo && (xo->flags & XFRM_DEV_RESUME)) { if (err) { XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR); kfree_skb(skb); return; } skb_push(skb, skb->data - skb_mac_header(skb)); secpath_reset(skb); xfrm_dev_resume(skb); } else { if (!err && x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP) esp_output_tail_tcp(x, skb); else xfrm_output_resume(skb->sk, skb, err); } } /* Move ESP header back into place. */ static void esp_restore_header(struct sk_buff *skb, unsigned int offset) { struct ip_esp_hdr *esph = (void *)(skb->data + offset); void *tmp = ESP_SKB_CB(skb)->tmp; __be32 *seqhi = esp_tmp_extra(tmp); esph->seq_no = esph->spi; esph->spi = *seqhi; } static void esp_output_restore_header(struct sk_buff *skb) { void *tmp = ESP_SKB_CB(skb)->tmp; struct esp_output_extra *extra = esp_tmp_extra(tmp); esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff - sizeof(__be32)); } static struct ip_esp_hdr *esp_output_set_extra(struct sk_buff *skb, struct xfrm_state *x, struct ip_esp_hdr *esph, struct esp_output_extra *extra) { /* For ESN we move the header forward by 4 bytes to * accommodate the high bits. We will move it back after * encryption. */ if ((x->props.flags & XFRM_STATE_ESN)) { __u32 seqhi; struct xfrm_offload *xo = xfrm_offload(skb); if (xo) seqhi = xo->seq.hi; else seqhi = XFRM_SKB_CB(skb)->seq.output.hi; extra->esphoff = (unsigned char *)esph - skb_transport_header(skb); esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4); extra->seqhi = esph->spi; esph->seq_no = htonl(seqhi); } esph->spi = x->id.spi; return esph; } static void esp_output_done_esn(void *data, int err) { struct sk_buff *skb = data; esp_output_restore_header(skb); esp_output_done(data, err); } static struct ip_esp_hdr *esp_output_udp_encap(struct sk_buff *skb, int encap_type, struct esp_info *esp, __be16 sport, __be16 dport) { struct udphdr *uh; __be32 *udpdata32; unsigned int len; len = skb->len + esp->tailen - skb_transport_offset(skb); if (len + sizeof(struct iphdr) > IP_MAX_MTU) return ERR_PTR(-EMSGSIZE); uh = (struct udphdr *)esp->esph; uh->source = sport; uh->dest = dport; uh->len = htons(len); uh->check = 0; *skb_mac_header(skb) = IPPROTO_UDP; if (encap_type == UDP_ENCAP_ESPINUDP_NON_IKE) { udpdata32 = (__be32 *)(uh + 1); udpdata32[0] = udpdata32[1] = 0; return (struct ip_esp_hdr *)(udpdata32 + 2); } return (struct ip_esp_hdr *)(uh + 1); } #ifdef CONFIG_INET_ESPINTCP static struct ip_esp_hdr *esp_output_tcp_encap(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { __be16 *lenp = (void *)esp->esph; struct ip_esp_hdr *esph; unsigned int len; struct sock *sk; len = skb->len + esp->tailen - skb_transport_offset(skb); if (len > IP_MAX_MTU) return ERR_PTR(-EMSGSIZE); rcu_read_lock(); sk = esp_find_tcp_sk(x); rcu_read_unlock(); if (IS_ERR(sk)) return ERR_CAST(sk); *lenp = htons(len); esph = (struct ip_esp_hdr *)(lenp + 1); return esph; } #else static struct ip_esp_hdr *esp_output_tcp_encap(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { return ERR_PTR(-EOPNOTSUPP); } #endif static int esp_output_encap(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { struct xfrm_encap_tmpl *encap = x->encap; struct ip_esp_hdr *esph; __be16 sport, dport; int encap_type; spin_lock_bh(&x->lock); sport = encap->encap_sport; dport = encap->encap_dport; encap_type = encap->encap_type; spin_unlock_bh(&x->lock); switch (encap_type) { default: case UDP_ENCAP_ESPINUDP: case UDP_ENCAP_ESPINUDP_NON_IKE: esph = esp_output_udp_encap(skb, encap_type, esp, sport, dport); break; case TCP_ENCAP_ESPINTCP: esph = esp_output_tcp_encap(x, skb, esp); break; } if (IS_ERR(esph)) return PTR_ERR(esph); esp->esph = esph; return 0; } int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { u8 *tail; int nfrags; int esph_offset; struct page *page; struct sk_buff *trailer; int tailen = esp->tailen; /* this is non-NULL only with TCP/UDP Encapsulation */ if (x->encap) { int err = esp_output_encap(x, skb, esp); if (err < 0) return err; } if (ALIGN(tailen, L1_CACHE_BYTES) > PAGE_SIZE || ALIGN(skb->data_len, L1_CACHE_BYTES) > PAGE_SIZE) goto cow; if (!skb_cloned(skb)) { if (tailen <= skb_tailroom(skb)) { nfrags = 1; trailer = skb; tail = skb_tail_pointer(trailer); goto skip_cow; } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) && !skb_has_frag_list(skb)) { int allocsize; struct sock *sk = skb->sk; struct page_frag *pfrag = &x->xfrag; esp->inplace = false; allocsize = ALIGN(tailen, L1_CACHE_BYTES); spin_lock_bh(&x->lock); if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { spin_unlock_bh(&x->lock); goto cow; } page = pfrag->page; get_page(page); tail = page_address(page) + pfrag->offset; esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); nfrags = skb_shinfo(skb)->nr_frags; __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, tailen); skb_shinfo(skb)->nr_frags = ++nfrags; pfrag->offset = pfrag->offset + allocsize; spin_unlock_bh(&x->lock); nfrags++; skb_len_add(skb, tailen); if (sk && sk_fullsock(sk)) refcount_add(tailen, &sk->sk_wmem_alloc); goto out; } } cow: esph_offset = (unsigned char *)esp->esph - skb_transport_header(skb); nfrags = skb_cow_data(skb, tailen, &trailer); if (nfrags < 0) goto out; tail = skb_tail_pointer(trailer); esp->esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset); skip_cow: esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); pskb_put(skb, trailer, tailen); out: return nfrags; } EXPORT_SYMBOL_GPL(esp_output_head); int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { u8 *iv; int alen; void *tmp; int ivlen; int assoclen; int extralen; struct page *page; struct ip_esp_hdr *esph; struct crypto_aead *aead; struct aead_request *req; struct scatterlist *sg, *dsg; struct esp_output_extra *extra; int err = -ENOMEM; assoclen = sizeof(struct ip_esp_hdr); extralen = 0; if (x->props.flags & XFRM_STATE_ESN) { extralen += sizeof(*extra); assoclen += sizeof(__be32); } aead = x->data; alen = crypto_aead_authsize(aead); ivlen = crypto_aead_ivsize(aead); tmp = esp_alloc_tmp(aead, esp->nfrags + 2, extralen); if (!tmp) goto error; extra = esp_tmp_extra(tmp); iv = esp_tmp_iv(aead, tmp, extralen); req = esp_tmp_req(aead, iv); sg = esp_req_sg(aead, req); if (esp->inplace) dsg = sg; else dsg = &sg[esp->nfrags]; esph = esp_output_set_extra(skb, x, esp->esph, extra); esp->esph = esph; sg_init_table(sg, esp->nfrags); err = skb_to_sgvec(skb, sg, (unsigned char *)esph - skb->data, assoclen + ivlen + esp->clen + alen); if (unlikely(err < 0)) goto error_free; if (!esp->inplace) { int allocsize; struct page_frag *pfrag = &x->xfrag; allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); spin_lock_bh(&x->lock); if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { spin_unlock_bh(&x->lock); goto error_free; } skb_shinfo(skb)->nr_frags = 1; page = pfrag->page; get_page(page); /* replace page frags in skb with new page */ __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); pfrag->offset = pfrag->offset + allocsize; spin_unlock_bh(&x->lock); sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); err = skb_to_sgvec(skb, dsg, (unsigned char *)esph - skb->data, assoclen + ivlen + esp->clen + alen); if (unlikely(err < 0)) goto error_free; } if ((x->props.flags & XFRM_STATE_ESN)) aead_request_set_callback(req, 0, esp_output_done_esn, skb); else aead_request_set_callback(req, 0, esp_output_done, skb); aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv); aead_request_set_ad(req, assoclen); memset(iv, 0, ivlen); memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8), min(ivlen, 8)); ESP_SKB_CB(skb)->tmp = tmp; err = crypto_aead_encrypt(req); switch (err) { case -EINPROGRESS: goto error; case -ENOSPC: err = NET_XMIT_DROP; break; case 0: if ((x->props.flags & XFRM_STATE_ESN)) esp_output_restore_header(skb); } if (sg != dsg) esp_ssg_unref(x, tmp); if (!err && x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP) err = esp_output_tail_tcp(x, skb); error_free: kfree(tmp); error: return err; } EXPORT_SYMBOL_GPL(esp_output_tail); static int esp_output(struct xfrm_state *x, struct sk_buff *skb) { int alen; int blksize; struct ip_esp_hdr *esph; struct crypto_aead *aead; struct esp_info esp; esp.inplace = true; esp.proto = *skb_mac_header(skb); *skb_mac_header(skb) = IPPROTO_ESP; /* skb is pure payload to encrypt */ aead = x->data; alen = crypto_aead_authsize(aead); esp.tfclen = 0; if (x->tfcpad) { struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); u32 padto; padto = min(x->tfcpad, xfrm_state_mtu(x, dst->child_mtu_cached)); if (skb->len < padto) esp.tfclen = padto - skb->len; } blksize = ALIGN(crypto_aead_blocksize(aead), 4); esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); esp.plen = esp.clen - skb->len - esp.tfclen; esp.tailen = esp.tfclen + esp.plen + alen; esp.esph = ip_esp_hdr(skb); esp.nfrags = esp_output_head(x, skb, &esp); if (esp.nfrags < 0) return esp.nfrags; esph = esp.esph; esph->spi = x->id.spi; esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); skb_push(skb, -skb_network_offset(skb)); return esp_output_tail(x, skb, &esp); } static inline int esp_remove_trailer(struct sk_buff *skb) { struct xfrm_state *x = xfrm_input_state(skb); struct crypto_aead *aead = x->data; int alen, hlen, elen; int padlen, trimlen; __wsum csumdiff; u8 nexthdr[2]; int ret; alen = crypto_aead_authsize(aead); hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); elen = skb->len - hlen; if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2)) BUG(); ret = -EINVAL; padlen = nexthdr[0]; if (padlen + 2 + alen >= elen) { net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", padlen + 2, elen - alen); goto out; } trimlen = alen + padlen + 2; if (skb->ip_summed == CHECKSUM_COMPLETE) { csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0); skb->csum = csum_block_sub(skb->csum, csumdiff, skb->len - trimlen); } pskb_trim(skb, skb->len - trimlen); ret = nexthdr[1]; out: return ret; } int esp_input_done2(struct sk_buff *skb, int err) { const struct iphdr *iph; struct xfrm_state *x = xfrm_input_state(skb); struct xfrm_offload *xo = xfrm_offload(skb); struct crypto_aead *aead = x->data; int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); int ihl; if (!xo || !(xo->flags & CRYPTO_DONE)) kfree(ESP_SKB_CB(skb)->tmp); if (unlikely(err)) goto out; err = esp_remove_trailer(skb); if (unlikely(err < 0)) goto out; iph = ip_hdr(skb); ihl = iph->ihl * 4; if (x->encap) { struct xfrm_encap_tmpl *encap = x->encap; struct tcphdr *th = (void *)(skb_network_header(skb) + ihl); struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); __be16 source; switch (x->encap->encap_type) { case TCP_ENCAP_ESPINTCP: source = th->source; break; case UDP_ENCAP_ESPINUDP: case UDP_ENCAP_ESPINUDP_NON_IKE: source = uh->source; break; default: WARN_ON_ONCE(1); err = -EINVAL; goto out; } /* * 1) if the NAT-T peer's IP or port changed then * advertize the change to the keying daemon. * This is an inbound SA, so just compare * SRC ports. */ if (iph->saddr != x->props.saddr.a4 || source != encap->encap_sport) { xfrm_address_t ipaddr; ipaddr.a4 = iph->saddr; km_new_mapping(x, &ipaddr, source); /* XXX: perhaps add an extra * policy check here, to see * if we should allow or * reject a packet from a * different source * address/port. */ } /* * 2) ignore UDP/TCP checksums in case * of NAT-T in Transport Mode, or * perform other post-processing fixes * as per draft-ietf-ipsec-udp-encaps-06, * section 3.1.2 */ if (x->props.mode == XFRM_MODE_TRANSPORT) skb->ip_summed = CHECKSUM_UNNECESSARY; } skb_pull_rcsum(skb, hlen); if (x->props.mode == XFRM_MODE_TUNNEL) skb_reset_transport_header(skb); else skb_set_transport_header(skb, -ihl); /* RFC4303: Drop dummy packets without any error */ if (err == IPPROTO_NONE) err = -EINVAL; out: return err; } EXPORT_SYMBOL_GPL(esp_input_done2); static void esp_input_done(void *data, int err) { struct sk_buff *skb = data; xfrm_input_resume(skb, esp_input_done2(skb, err)); } static void esp_input_restore_header(struct sk_buff *skb) { esp_restore_header(skb, 0); __skb_pull(skb, 4); } static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) { struct xfrm_state *x = xfrm_input_state(skb); struct ip_esp_hdr *esph; /* For ESN we move the header forward by 4 bytes to * accommodate the high bits. We will move it back after * decryption. */ if ((x->props.flags & XFRM_STATE_ESN)) { esph = skb_push(skb, 4); *seqhi = esph->spi; esph->spi = esph->seq_no; esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; } } static void esp_input_done_esn(void *data, int err) { struct sk_buff *skb = data; esp_input_restore_header(skb); esp_input_done(data, err); } /* * Note: detecting truncated vs. non-truncated authentication data is very * expensive, so we only support truncated data, which is the recommended * and common case. */ static int esp_input(struct xfrm_state *x, struct sk_buff *skb) { struct crypto_aead *aead = x->data; struct aead_request *req; struct sk_buff *trailer; int ivlen = crypto_aead_ivsize(aead); int elen = skb->len - sizeof(struct ip_esp_hdr) - ivlen; int nfrags; int assoclen; int seqhilen; __be32 *seqhi; void *tmp; u8 *iv; struct scatterlist *sg; int err = -EINVAL; if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + ivlen)) goto out; if (elen <= 0) goto out; assoclen = sizeof(struct ip_esp_hdr); seqhilen = 0; if (x->props.flags & XFRM_STATE_ESN) { seqhilen += sizeof(__be32); assoclen += seqhilen; } if (!skb_cloned(skb)) { if (!skb_is_nonlinear(skb)) { nfrags = 1; goto skip_cow; } else if (!skb_has_frag_list(skb)) { nfrags = skb_shinfo(skb)->nr_frags; nfrags++; goto skip_cow; } } err = skb_cow_data(skb, 0, &trailer); if (err < 0) goto out; nfrags = err; skip_cow: err = -ENOMEM; tmp = esp_alloc_tmp(aead, nfrags, seqhilen); if (!tmp) goto out; ESP_SKB_CB(skb)->tmp = tmp; seqhi = esp_tmp_extra(tmp); iv = esp_tmp_iv(aead, tmp, seqhilen); req = esp_tmp_req(aead, iv); sg = esp_req_sg(aead, req); esp_input_set_header(skb, seqhi); sg_init_table(sg, nfrags); err = skb_to_sgvec(skb, sg, 0, skb->len); if (unlikely(err < 0)) { kfree(tmp); goto out; } skb->ip_summed = CHECKSUM_NONE; if ((x->props.flags & XFRM_STATE_ESN)) aead_request_set_callback(req, 0, esp_input_done_esn, skb); else aead_request_set_callback(req, 0, esp_input_done, skb); aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); aead_request_set_ad(req, assoclen); err = crypto_aead_decrypt(req); if (err == -EINPROGRESS) goto out; if ((x->props.flags & XFRM_STATE_ESN)) esp_input_restore_header(skb); err = esp_input_done2(skb, err); out: return err; } static int esp4_err(struct sk_buff *skb, u32 info) { struct net *net = dev_net(skb->dev); const struct iphdr *iph = (const struct iphdr *)skb->data; struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); struct xfrm_state *x; switch (icmp_hdr(skb)->type) { case ICMP_DEST_UNREACH: if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) return 0; break; case ICMP_REDIRECT: break; default: return 0; } x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, esph->spi, IPPROTO_ESP, AF_INET); if (!x) return 0; if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) ipv4_update_pmtu(skb, net, info, 0, IPPROTO_ESP); else ipv4_redirect(skb, net, 0, IPPROTO_ESP); xfrm_state_put(x); return 0; } static void esp_destroy(struct xfrm_state *x) { struct crypto_aead *aead = x->data; if (!aead) return; crypto_free_aead(aead); } static int esp_init_aead(struct xfrm_state *x, struct netlink_ext_ack *extack) { char aead_name[CRYPTO_MAX_ALG_NAME]; struct crypto_aead *aead; int err; if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) { NL_SET_ERR_MSG(extack, "Algorithm name is too long"); return -ENAMETOOLONG; } aead = crypto_alloc_aead(aead_name, 0, 0); err = PTR_ERR(aead); if (IS_ERR(aead)) goto error; x->data = aead; err = crypto_aead_setkey(aead, x->aead->alg_key, (x->aead->alg_key_len + 7) / 8); if (err) goto error; err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); if (err) goto error; return 0; error: NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); return err; } static int esp_init_authenc(struct xfrm_state *x, struct netlink_ext_ack *extack) { struct crypto_aead *aead; struct crypto_authenc_key_param *param; struct rtattr *rta; char *key; char *p; char authenc_name[CRYPTO_MAX_ALG_NAME]; unsigned int keylen; int err; err = -ENAMETOOLONG; if ((x->props.flags & XFRM_STATE_ESN)) { if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, "%s%sauthencesn(%s,%s)%s", x->geniv ?: "", x->geniv ? "(" : "", x->aalg ? x->aalg->alg_name : "digest_null", x->ealg->alg_name, x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) { NL_SET_ERR_MSG(extack, "Algorithm name is too long"); goto error; } } else { if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, "%s%sauthenc(%s,%s)%s", x->geniv ?: "", x->geniv ? "(" : "", x->aalg ? x->aalg->alg_name : "digest_null", x->ealg->alg_name, x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) { NL_SET_ERR_MSG(extack, "Algorithm name is too long"); goto error; } } aead = crypto_alloc_aead(authenc_name, 0, 0); err = PTR_ERR(aead); if (IS_ERR(aead)) { NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); goto error; } x->data = aead; keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); err = -ENOMEM; key = kmalloc(keylen, GFP_KERNEL); if (!key) goto error; p = key; rta = (void *)p; rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; rta->rta_len = RTA_LENGTH(sizeof(*param)); param = RTA_DATA(rta); p += RTA_SPACE(sizeof(*param)); if (x->aalg) { struct xfrm_algo_desc *aalg_desc; memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); p += (x->aalg->alg_key_len + 7) / 8; aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); BUG_ON(!aalg_desc); err = -EINVAL; if (aalg_desc->uinfo.auth.icv_fullbits / 8 != crypto_aead_authsize(aead)) { NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); goto free_key; } err = crypto_aead_setauthsize( aead, x->aalg->alg_trunc_len / 8); if (err) { NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); goto free_key; } } param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); err = crypto_aead_setkey(aead, key, keylen); free_key: kfree_sensitive(key); error: return err; } static int esp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack) { struct crypto_aead *aead; u32 align; int err; x->data = NULL; if (x->aead) { err = esp_init_aead(x, extack); } else if (x->ealg) { err = esp_init_authenc(x, extack); } else { NL_SET_ERR_MSG(extack, "ESP: AEAD or CRYPT must be provided"); err = -EINVAL; } if (err) goto error; aead = x->data; x->props.header_len = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); if (x->props.mode == XFRM_MODE_TUNNEL) x->props.header_len += sizeof(struct iphdr); else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6) x->props.header_len += IPV4_BEET_PHMAXLEN; if (x->encap) { struct xfrm_encap_tmpl *encap = x->encap; switch (encap->encap_type) { default: NL_SET_ERR_MSG(extack, "Unsupported encapsulation type for ESP"); err = -EINVAL; goto error; case UDP_ENCAP_ESPINUDP: x->props.header_len += sizeof(struct udphdr); break; case UDP_ENCAP_ESPINUDP_NON_IKE: x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32); break; #ifdef CONFIG_INET_ESPINTCP case TCP_ENCAP_ESPINTCP: /* only the length field, TCP encap is done by * the socket */ x->props.header_len += 2; break; #endif } } align = ALIGN(crypto_aead_blocksize(aead), 4); x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); error: return err; } static int esp4_rcv_cb(struct sk_buff *skb, int err) { return 0; } static const struct xfrm_type esp_type = { .owner = THIS_MODULE, .proto = IPPROTO_ESP, .flags = XFRM_TYPE_REPLAY_PROT, .init_state = esp_init_state, .destructor = esp_destroy, .input = esp_input, .output = esp_output, }; static struct xfrm4_protocol esp4_protocol = { .handler = xfrm4_rcv, .input_handler = xfrm_input, .cb_handler = esp4_rcv_cb, .err_handler = esp4_err, .priority = 0, }; static int __init esp4_init(void) { if (xfrm_register_type(&esp_type, AF_INET) < 0) { pr_info("%s: can't add xfrm type\n", __func__); return -EAGAIN; } if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) { pr_info("%s: can't add protocol\n", __func__); xfrm_unregister_type(&esp_type, AF_INET); return -EAGAIN; } return 0; } static void __exit esp4_fini(void) { if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0) pr_info("%s: can't remove protocol\n", __func__); xfrm_unregister_type(&esp_type, AF_INET); } module_init(esp4_init); module_exit(esp4_fini); MODULE_LICENSE("GPL"); MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);
linux-master
net/ipv4/esp4.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * Syncookies implementation for the Linux kernel * * Copyright (C) 1997 Andi Kleen * Based on ideas by D.J.Bernstein and Eric Schenk. */ #include <linux/tcp.h> #include <linux/siphash.h> #include <linux/kernel.h> #include <linux/export.h> #include <net/secure_seq.h> #include <net/tcp.h> #include <net/route.h> static siphash_aligned_key_t syncookie_secret[2]; #define COOKIEBITS 24 /* Upper bits store count */ #define COOKIEMASK (((__u32)1 << COOKIEBITS) - 1) /* TCP Timestamp: 6 lowest bits of timestamp sent in the cookie SYN-ACK * stores TCP options: * * MSB LSB * | 31 ... 6 | 5 | 4 | 3 2 1 0 | * | Timestamp | ECN | SACK | WScale | * * When we receive a valid cookie-ACK, we look at the echoed tsval (if * any) to figure out which TCP options we should use for the rebuilt * connection. * * A WScale setting of '0xf' (which is an invalid scaling value) * means that original syn did not include the TCP window scaling option. */ #define TS_OPT_WSCALE_MASK 0xf #define TS_OPT_SACK BIT(4) #define TS_OPT_ECN BIT(5) /* There is no TS_OPT_TIMESTAMP: * if ACK contains timestamp option, we already know it was * requested/supported by the syn/synack exchange. */ #define TSBITS 6 #define TSMASK (((__u32)1 << TSBITS) - 1) static u32 cookie_hash(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport, u32 count, int c) { net_get_random_once(syncookie_secret, sizeof(syncookie_secret)); return siphash_4u32((__force u32)saddr, (__force u32)daddr, (__force u32)sport << 16 | (__force u32)dport, count, &syncookie_secret[c]); } /* * when syncookies are in effect and tcp timestamps are enabled we encode * tcp options in the lower bits of the timestamp value that will be * sent in the syn-ack. * Since subsequent timestamps use the normal tcp_time_stamp value, we * must make sure that the resulting initial timestamp is <= tcp_time_stamp. */ u64 cookie_init_timestamp(struct request_sock *req, u64 now) { struct inet_request_sock *ireq; u32 ts, ts_now = tcp_ns_to_ts(now); u32 options = 0; ireq = inet_rsk(req); options = ireq->wscale_ok ? ireq->snd_wscale : TS_OPT_WSCALE_MASK; if (ireq->sack_ok) options |= TS_OPT_SACK; if (ireq->ecn_ok) options |= TS_OPT_ECN; ts = ts_now & ~TSMASK; ts |= options; if (ts > ts_now) { ts >>= TSBITS; ts--; ts <<= TSBITS; ts |= options; } return (u64)ts * (NSEC_PER_SEC / TCP_TS_HZ); } static __u32 secure_tcp_syn_cookie(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport, __u32 sseq, __u32 data) { /* * Compute the secure sequence number. * The output should be: * HASH(sec1,saddr,sport,daddr,dport,sec1) + sseq + (count * 2^24) * + (HASH(sec2,saddr,sport,daddr,dport,count,sec2) % 2^24). * Where sseq is their sequence number and count increases every * minute by 1. * As an extra hack, we add a small "data" value that encodes the * MSS into the second hash value. */ u32 count = tcp_cookie_time(); return (cookie_hash(saddr, daddr, sport, dport, 0, 0) + sseq + (count << COOKIEBITS) + ((cookie_hash(saddr, daddr, sport, dport, count, 1) + data) & COOKIEMASK)); } /* * This retrieves the small "data" value from the syncookie. * If the syncookie is bad, the data returned will be out of * range. This must be checked by the caller. * * The count value used to generate the cookie must be less than * MAX_SYNCOOKIE_AGE minutes in the past. * The return value (__u32)-1 if this test fails. */ static __u32 check_tcp_syn_cookie(__u32 cookie, __be32 saddr, __be32 daddr, __be16 sport, __be16 dport, __u32 sseq) { u32 diff, count = tcp_cookie_time(); /* Strip away the layers from the cookie */ cookie -= cookie_hash(saddr, daddr, sport, dport, 0, 0) + sseq; /* Cookie is now reduced to (count * 2^24) ^ (hash % 2^24) */ diff = (count - (cookie >> COOKIEBITS)) & ((__u32) -1 >> COOKIEBITS); if (diff >= MAX_SYNCOOKIE_AGE) return (__u32)-1; return (cookie - cookie_hash(saddr, daddr, sport, dport, count - diff, 1)) & COOKIEMASK; /* Leaving the data behind */ } /* * MSS Values are chosen based on the 2011 paper * 'An Analysis of TCP Maximum Segement Sizes' by S. Alcock and R. Nelson. * Values .. * .. lower than 536 are rare (< 0.2%) * .. between 537 and 1299 account for less than < 1.5% of observed values * .. in the 1300-1349 range account for about 15 to 20% of observed mss values * .. exceeding 1460 are very rare (< 0.04%) * * 1460 is the single most frequently announced mss value (30 to 46% depending * on monitor location). Table must be sorted. */ static __u16 const msstab[] = { 536, 1300, 1440, /* 1440, 1452: PPPoE */ 1460, }; /* * Generate a syncookie. mssp points to the mss, which is returned * rounded down to the value encoded in the cookie. */ u32 __cookie_v4_init_sequence(const struct iphdr *iph, const struct tcphdr *th, u16 *mssp) { int mssind; const __u16 mss = *mssp; for (mssind = ARRAY_SIZE(msstab) - 1; mssind ; mssind--) if (mss >= msstab[mssind]) break; *mssp = msstab[mssind]; return secure_tcp_syn_cookie(iph->saddr, iph->daddr, th->source, th->dest, ntohl(th->seq), mssind); } EXPORT_SYMBOL_GPL(__cookie_v4_init_sequence); __u32 cookie_v4_init_sequence(const struct sk_buff *skb, __u16 *mssp) { const struct iphdr *iph = ip_hdr(skb); const struct tcphdr *th = tcp_hdr(skb); return __cookie_v4_init_sequence(iph, th, mssp); } /* * Check if a ack sequence number is a valid syncookie. * Return the decoded mss if it is, or 0 if not. */ int __cookie_v4_check(const struct iphdr *iph, const struct tcphdr *th, u32 cookie) { __u32 seq = ntohl(th->seq) - 1; __u32 mssind = check_tcp_syn_cookie(cookie, iph->saddr, iph->daddr, th->source, th->dest, seq); return mssind < ARRAY_SIZE(msstab) ? msstab[mssind] : 0; } EXPORT_SYMBOL_GPL(__cookie_v4_check); struct sock *tcp_get_cookie_sock(struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct dst_entry *dst, u32 tsoff) { struct inet_connection_sock *icsk = inet_csk(sk); struct sock *child; bool own_req; child = icsk->icsk_af_ops->syn_recv_sock(sk, skb, req, dst, NULL, &own_req); if (child) { refcount_set(&req->rsk_refcnt, 1); tcp_sk(child)->tsoffset = tsoff; sock_rps_save_rxhash(child, skb); if (rsk_drop_req(req)) { reqsk_put(req); return child; } if (inet_csk_reqsk_queue_add(sk, req, child)) return child; bh_unlock_sock(child); sock_put(child); } __reqsk_free(req); return NULL; } EXPORT_SYMBOL(tcp_get_cookie_sock); /* * when syncookies are in effect and tcp timestamps are enabled we stored * additional tcp options in the timestamp. * This extracts these options from the timestamp echo. * * return false if we decode a tcp option that is disabled * on the host. */ bool cookie_timestamp_decode(const struct net *net, struct tcp_options_received *tcp_opt) { /* echoed timestamp, lowest bits contain options */ u32 options = tcp_opt->rcv_tsecr; if (!tcp_opt->saw_tstamp) { tcp_clear_options(tcp_opt); return true; } if (!READ_ONCE(net->ipv4.sysctl_tcp_timestamps)) return false; tcp_opt->sack_ok = (options & TS_OPT_SACK) ? TCP_SACK_SEEN : 0; if (tcp_opt->sack_ok && !READ_ONCE(net->ipv4.sysctl_tcp_sack)) return false; if ((options & TS_OPT_WSCALE_MASK) == TS_OPT_WSCALE_MASK) return true; /* no window scaling */ tcp_opt->wscale_ok = 1; tcp_opt->snd_wscale = options & TS_OPT_WSCALE_MASK; return READ_ONCE(net->ipv4.sysctl_tcp_window_scaling) != 0; } EXPORT_SYMBOL(cookie_timestamp_decode); bool cookie_ecn_ok(const struct tcp_options_received *tcp_opt, const struct net *net, const struct dst_entry *dst) { bool ecn_ok = tcp_opt->rcv_tsecr & TS_OPT_ECN; if (!ecn_ok) return false; if (READ_ONCE(net->ipv4.sysctl_tcp_ecn)) return true; return dst_feature(dst, RTAX_FEATURE_ECN); } EXPORT_SYMBOL(cookie_ecn_ok); struct request_sock *cookie_tcp_reqsk_alloc(const struct request_sock_ops *ops, const struct tcp_request_sock_ops *af_ops, struct sock *sk, struct sk_buff *skb) { struct tcp_request_sock *treq; struct request_sock *req; if (sk_is_mptcp(sk)) req = mptcp_subflow_reqsk_alloc(ops, sk, false); else req = inet_reqsk_alloc(ops, sk, false); if (!req) return NULL; treq = tcp_rsk(req); /* treq->af_specific might be used to perform TCP_MD5 lookup */ treq->af_specific = af_ops; treq->syn_tos = TCP_SKB_CB(skb)->ip_dsfield; #if IS_ENABLED(CONFIG_MPTCP) treq->is_mptcp = sk_is_mptcp(sk); if (treq->is_mptcp) { int err = mptcp_subflow_init_cookie_req(req, sk, skb); if (err) { reqsk_free(req); return NULL; } } #endif return req; } EXPORT_SYMBOL_GPL(cookie_tcp_reqsk_alloc); /* On input, sk is a listener. * Output is listener if incoming packet would not create a child * NULL if memory could not be allocated. */ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb) { struct ip_options *opt = &TCP_SKB_CB(skb)->header.h4.opt; struct tcp_options_received tcp_opt; struct inet_request_sock *ireq; struct tcp_request_sock *treq; struct tcp_sock *tp = tcp_sk(sk); const struct tcphdr *th = tcp_hdr(skb); __u32 cookie = ntohl(th->ack_seq) - 1; struct sock *ret = sk; struct request_sock *req; int full_space, mss; struct rtable *rt; __u8 rcv_wscale; struct flowi4 fl4; u32 tsoff = 0; if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies) || !th->ack || th->rst) goto out; if (tcp_synq_no_recent_overflow(sk)) goto out; mss = __cookie_v4_check(ip_hdr(skb), th, cookie); if (mss == 0) { __NET_INC_STATS(sock_net(sk), LINUX_MIB_SYNCOOKIESFAILED); goto out; } __NET_INC_STATS(sock_net(sk), LINUX_MIB_SYNCOOKIESRECV); /* check for timestamp cookie support */ memset(&tcp_opt, 0, sizeof(tcp_opt)); tcp_parse_options(sock_net(sk), skb, &tcp_opt, 0, NULL); if (tcp_opt.saw_tstamp && tcp_opt.rcv_tsecr) { tsoff = secure_tcp_ts_off(sock_net(sk), ip_hdr(skb)->daddr, ip_hdr(skb)->saddr); tcp_opt.rcv_tsecr -= tsoff; } if (!cookie_timestamp_decode(sock_net(sk), &tcp_opt)) goto out; ret = NULL; req = cookie_tcp_reqsk_alloc(&tcp_request_sock_ops, &tcp_request_sock_ipv4_ops, sk, skb); if (!req) goto out; ireq = inet_rsk(req); treq = tcp_rsk(req); treq->rcv_isn = ntohl(th->seq) - 1; treq->snt_isn = cookie; treq->ts_off = 0; treq->txhash = net_tx_rndhash(); req->mss = mss; ireq->ir_num = ntohs(th->dest); ireq->ir_rmt_port = th->source; sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); ireq->ir_mark = inet_request_mark(sk, skb); ireq->snd_wscale = tcp_opt.snd_wscale; ireq->sack_ok = tcp_opt.sack_ok; ireq->wscale_ok = tcp_opt.wscale_ok; ireq->tstamp_ok = tcp_opt.saw_tstamp; req->ts_recent = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0; treq->snt_synack = 0; treq->tfo_listener = false; if (IS_ENABLED(CONFIG_SMC)) ireq->smc_ok = 0; ireq->ir_iif = inet_request_bound_dev_if(sk, skb); /* We throwed the options of the initial SYN away, so we hope * the ACK carries the same options again (see RFC1122 4.2.3.8) */ RCU_INIT_POINTER(ireq->ireq_opt, tcp_v4_save_options(sock_net(sk), skb)); if (security_inet_conn_request(sk, skb, req)) { reqsk_free(req); goto out; } req->num_retrans = 0; /* * We need to lookup the route here to get at the correct * window size. We should better make sure that the window size * hasn't changed since we received the original syn, but I see * no easy way to do this. */ flowi4_init_output(&fl4, ireq->ir_iif, ireq->ir_mark, ip_sock_rt_tos(sk), ip_sock_rt_scope(sk), IPPROTO_TCP, inet_sk_flowi_flags(sk), opt->srr ? opt->faddr : ireq->ir_rmt_addr, ireq->ir_loc_addr, th->source, th->dest, sk->sk_uid); security_req_classify_flow(req, flowi4_to_flowi_common(&fl4)); rt = ip_route_output_key(sock_net(sk), &fl4); if (IS_ERR(rt)) { reqsk_free(req); goto out; } /* Try to redo what tcp_v4_send_synack did. */ req->rsk_window_clamp = tp->window_clamp ? :dst_metric(&rt->dst, RTAX_WINDOW); /* limit the window selection if the user enforce a smaller rx buffer */ full_space = tcp_full_space(sk); if (sk->sk_userlocks & SOCK_RCVBUF_LOCK && (req->rsk_window_clamp > full_space || req->rsk_window_clamp == 0)) req->rsk_window_clamp = full_space; tcp_select_initial_window(sk, full_space, req->mss, &req->rsk_rcv_wnd, &req->rsk_window_clamp, ireq->wscale_ok, &rcv_wscale, dst_metric(&rt->dst, RTAX_INITRWND)); ireq->rcv_wscale = rcv_wscale; ireq->ecn_ok = cookie_ecn_ok(&tcp_opt, sock_net(sk), &rt->dst); ret = tcp_get_cookie_sock(sk, skb, req, &rt->dst, tsoff); /* ip_queue_xmit() depends on our flow being setup * Normal sockets get it right from inet_csk_route_child_sock() */ if (ret) inet_sk(ret)->cork.fl.u.ip4 = fl4; out: return ret; }
linux-master
net/ipv4/syncookies.c
// SPDX-License-Identifier: GPL-2.0-only /* * Binary Increase Congestion control for TCP * Home page: * http://netsrv.csc.ncsu.edu/twiki/bin/view/Main/BIC * This is from the implementation of BICTCP in * Lison-Xu, Kahaled Harfoush, and Injong Rhee. * "Binary Increase Congestion Control for Fast, Long Distance * Networks" in InfoComm 2004 * Available from: * http://netsrv.csc.ncsu.edu/export/bitcp.pdf * * Unless BIC is enabled and congestion window is large * this behaves the same as the original Reno. */ #include <linux/mm.h> #include <linux/module.h> #include <net/tcp.h> #define BICTCP_BETA_SCALE 1024 /* Scale factor beta calculation * max_cwnd = snd_cwnd * beta */ #define BICTCP_B 4 /* * In binary search, * go to point (max+min)/N */ static int fast_convergence = 1; static int max_increment = 16; static int low_window = 14; static int beta = 819; /* = 819/1024 (BICTCP_BETA_SCALE) */ static int initial_ssthresh; static int smooth_part = 20; module_param(fast_convergence, int, 0644); MODULE_PARM_DESC(fast_convergence, "turn on/off fast convergence"); module_param(max_increment, int, 0644); MODULE_PARM_DESC(max_increment, "Limit on increment allowed during binary search"); module_param(low_window, int, 0644); MODULE_PARM_DESC(low_window, "lower bound on congestion window (for TCP friendliness)"); module_param(beta, int, 0644); MODULE_PARM_DESC(beta, "beta for multiplicative increase"); module_param(initial_ssthresh, int, 0644); MODULE_PARM_DESC(initial_ssthresh, "initial value of slow start threshold"); module_param(smooth_part, int, 0644); MODULE_PARM_DESC(smooth_part, "log(B/(B*Smin))/log(B/(B-1))+B, # of RTT from Wmax-B to Wmax"); /* BIC TCP Parameters */ struct bictcp { u32 cnt; /* increase cwnd by 1 after ACKs */ u32 last_max_cwnd; /* last maximum snd_cwnd */ u32 last_cwnd; /* the last snd_cwnd */ u32 last_time; /* time when updated last_cwnd */ u32 epoch_start; /* beginning of an epoch */ #define ACK_RATIO_SHIFT 4 u32 delayed_ack; /* estimate the ratio of Packets/ACKs << 4 */ }; static inline void bictcp_reset(struct bictcp *ca) { ca->cnt = 0; ca->last_max_cwnd = 0; ca->last_cwnd = 0; ca->last_time = 0; ca->epoch_start = 0; ca->delayed_ack = 2 << ACK_RATIO_SHIFT; } static void bictcp_init(struct sock *sk) { struct bictcp *ca = inet_csk_ca(sk); bictcp_reset(ca); if (initial_ssthresh) tcp_sk(sk)->snd_ssthresh = initial_ssthresh; } /* * Compute congestion window to use. */ static inline void bictcp_update(struct bictcp *ca, u32 cwnd) { if (ca->last_cwnd == cwnd && (s32)(tcp_jiffies32 - ca->last_time) <= HZ / 32) return; ca->last_cwnd = cwnd; ca->last_time = tcp_jiffies32; if (ca->epoch_start == 0) /* record the beginning of an epoch */ ca->epoch_start = tcp_jiffies32; /* start off normal */ if (cwnd <= low_window) { ca->cnt = cwnd; return; } /* binary increase */ if (cwnd < ca->last_max_cwnd) { __u32 dist = (ca->last_max_cwnd - cwnd) / BICTCP_B; if (dist > max_increment) /* linear increase */ ca->cnt = cwnd / max_increment; else if (dist <= 1U) /* binary search increase */ ca->cnt = (cwnd * smooth_part) / BICTCP_B; else /* binary search increase */ ca->cnt = cwnd / dist; } else { /* slow start AMD linear increase */ if (cwnd < ca->last_max_cwnd + BICTCP_B) /* slow start */ ca->cnt = (cwnd * smooth_part) / BICTCP_B; else if (cwnd < ca->last_max_cwnd + max_increment*(BICTCP_B-1)) /* slow start */ ca->cnt = (cwnd * (BICTCP_B-1)) / (cwnd - ca->last_max_cwnd); else /* linear increase */ ca->cnt = cwnd / max_increment; } /* if in slow start or link utilization is very low */ if (ca->last_max_cwnd == 0) { if (ca->cnt > 20) /* increase cwnd 5% per RTT */ ca->cnt = 20; } ca->cnt = (ca->cnt << ACK_RATIO_SHIFT) / ca->delayed_ack; if (ca->cnt == 0) /* cannot be zero */ ca->cnt = 1; } static void bictcp_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); if (!tcp_is_cwnd_limited(sk)) return; if (tcp_in_slow_start(tp)) { acked = tcp_slow_start(tp, acked); if (!acked) return; } bictcp_update(ca, tcp_snd_cwnd(tp)); tcp_cong_avoid_ai(tp, ca->cnt, acked); } /* * behave like Reno until low_window is reached, * then increase congestion window slowly */ static u32 bictcp_recalc_ssthresh(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); ca->epoch_start = 0; /* end of epoch */ /* Wmax and fast convergence */ if (tcp_snd_cwnd(tp) < ca->last_max_cwnd && fast_convergence) ca->last_max_cwnd = (tcp_snd_cwnd(tp) * (BICTCP_BETA_SCALE + beta)) / (2 * BICTCP_BETA_SCALE); else ca->last_max_cwnd = tcp_snd_cwnd(tp); if (tcp_snd_cwnd(tp) <= low_window) return max(tcp_snd_cwnd(tp) >> 1U, 2U); else return max((tcp_snd_cwnd(tp) * beta) / BICTCP_BETA_SCALE, 2U); } static void bictcp_state(struct sock *sk, u8 new_state) { if (new_state == TCP_CA_Loss) bictcp_reset(inet_csk_ca(sk)); } /* Track delayed acknowledgment ratio using sliding window * ratio = (15*ratio + sample) / 16 */ static void bictcp_acked(struct sock *sk, const struct ack_sample *sample) { const struct inet_connection_sock *icsk = inet_csk(sk); if (icsk->icsk_ca_state == TCP_CA_Open) { struct bictcp *ca = inet_csk_ca(sk); ca->delayed_ack += sample->pkts_acked - (ca->delayed_ack >> ACK_RATIO_SHIFT); } } static struct tcp_congestion_ops bictcp __read_mostly = { .init = bictcp_init, .ssthresh = bictcp_recalc_ssthresh, .cong_avoid = bictcp_cong_avoid, .set_state = bictcp_state, .undo_cwnd = tcp_reno_undo_cwnd, .pkts_acked = bictcp_acked, .owner = THIS_MODULE, .name = "bic", }; static int __init bictcp_register(void) { BUILD_BUG_ON(sizeof(struct bictcp) > ICSK_CA_PRIV_SIZE); return tcp_register_congestion_control(&bictcp); } static void __exit bictcp_unregister(void) { tcp_unregister_congestion_control(&bictcp); } module_init(bictcp_register); module_exit(bictcp_unregister); MODULE_AUTHOR("Stephen Hemminger"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("BIC TCP");
linux-master
net/ipv4/tcp_bic.c
// SPDX-License-Identifier: GPL-2.0-only /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Implementation of the Transmission Control Protocol(TCP). * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * Mark Evans, <[email protected]> * Corey Minyard <[email protected]> * Florian La Roche, <[email protected]> * Charles Hedrick, <[email protected]> * Linus Torvalds, <[email protected]> * Alan Cox, <[email protected]> * Matthew Dillon, <[email protected]> * Arnt Gulbrandsen, <[email protected]> * Jorge Cwik, <[email protected]> */ /* * Changes: Pedro Roque : Retransmit queue handled by TCP. * : Fragmentation on mtu decrease * : Segment collapse on retransmit * : AF independence * * Linus Torvalds : send_delayed_ack * David S. Miller : Charge memory using the right skb * during syn/ack processing. * David S. Miller : Output engine completely rewritten. * Andrea Arcangeli: SYNACK carry ts_recent in tsecr. * Cacophonix Gaul : draft-minshall-nagle-01 * J Hadi Salim : ECN support * */ #define pr_fmt(fmt) "TCP: " fmt #include <net/tcp.h> #include <net/mptcp.h> #include <linux/compiler.h> #include <linux/gfp.h> #include <linux/module.h> #include <linux/static_key.h> #include <trace/events/tcp.h> /* Refresh clocks of a TCP socket, * ensuring monotically increasing values. */ void tcp_mstamp_refresh(struct tcp_sock *tp) { u64 val = tcp_clock_ns(); tp->tcp_clock_cache = val; tp->tcp_mstamp = div_u64(val, NSEC_PER_USEC); } static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, int push_one, gfp_t gfp); /* Account for new data that has been sent to the network. */ static void tcp_event_new_data_sent(struct sock *sk, struct sk_buff *skb) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); unsigned int prior_packets = tp->packets_out; WRITE_ONCE(tp->snd_nxt, TCP_SKB_CB(skb)->end_seq); __skb_unlink(skb, &sk->sk_write_queue); tcp_rbtree_insert(&sk->tcp_rtx_queue, skb); if (tp->highest_sack == NULL) tp->highest_sack = skb; tp->packets_out += tcp_skb_pcount(skb); if (!prior_packets || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) tcp_rearm_rto(sk); NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPORIGDATASENT, tcp_skb_pcount(skb)); tcp_check_space(sk); } /* SND.NXT, if window was not shrunk or the amount of shrunk was less than one * window scaling factor due to loss of precision. * If window has been shrunk, what should we make? It is not clear at all. * Using SND.UNA we will fail to open window, SND.NXT is out of window. :-( * Anything in between SND.UNA...SND.UNA+SND.WND also can be already * invalid. OK, let's make this for now: */ static inline __u32 tcp_acceptable_seq(const struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); if (!before(tcp_wnd_end(tp), tp->snd_nxt) || (tp->rx_opt.wscale_ok && ((tp->snd_nxt - tcp_wnd_end(tp)) < (1 << tp->rx_opt.rcv_wscale)))) return tp->snd_nxt; else return tcp_wnd_end(tp); } /* Calculate mss to advertise in SYN segment. * RFC1122, RFC1063, draft-ietf-tcpimpl-pmtud-01 state that: * * 1. It is independent of path mtu. * 2. Ideally, it is maximal possible segment size i.e. 65535-40. * 3. For IPv4 it is reasonable to calculate it from maximal MTU of * attached devices, because some buggy hosts are confused by * large MSS. * 4. We do not make 3, we advertise MSS, calculated from first * hop device mtu, but allow to raise it to ip_rt_min_advmss. * This may be overridden via information stored in routing table. * 5. Value 65535 for MSS is valid in IPv6 and means "as large as possible, * probably even Jumbo". */ static __u16 tcp_advertise_mss(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); const struct dst_entry *dst = __sk_dst_get(sk); int mss = tp->advmss; if (dst) { unsigned int metric = dst_metric_advmss(dst); if (metric < mss) { mss = metric; tp->advmss = mss; } } return (__u16)mss; } /* RFC2861. Reset CWND after idle period longer RTO to "restart window". * This is the first part of cwnd validation mechanism. */ void tcp_cwnd_restart(struct sock *sk, s32 delta) { struct tcp_sock *tp = tcp_sk(sk); u32 restart_cwnd = tcp_init_cwnd(tp, __sk_dst_get(sk)); u32 cwnd = tcp_snd_cwnd(tp); tcp_ca_event(sk, CA_EVENT_CWND_RESTART); tp->snd_ssthresh = tcp_current_ssthresh(sk); restart_cwnd = min(restart_cwnd, cwnd); while ((delta -= inet_csk(sk)->icsk_rto) > 0 && cwnd > restart_cwnd) cwnd >>= 1; tcp_snd_cwnd_set(tp, max(cwnd, restart_cwnd)); tp->snd_cwnd_stamp = tcp_jiffies32; tp->snd_cwnd_used = 0; } /* Congestion state accounting after a packet has been sent. */ static void tcp_event_data_sent(struct tcp_sock *tp, struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); const u32 now = tcp_jiffies32; if (tcp_packets_in_flight(tp) == 0) tcp_ca_event(sk, CA_EVENT_TX_START); tp->lsndtime = now; /* If it is a reply for ato after last received * packet, enter pingpong mode. */ if ((u32)(now - icsk->icsk_ack.lrcvtime) < icsk->icsk_ack.ato) inet_csk_enter_pingpong_mode(sk); } /* Account for an ACK we sent. */ static inline void tcp_event_ack_sent(struct sock *sk, unsigned int pkts, u32 rcv_nxt) { struct tcp_sock *tp = tcp_sk(sk); if (unlikely(tp->compressed_ack)) { NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPACKCOMPRESSED, tp->compressed_ack); tp->compressed_ack = 0; if (hrtimer_try_to_cancel(&tp->compressed_ack_timer) == 1) __sock_put(sk); } if (unlikely(rcv_nxt != tp->rcv_nxt)) return; /* Special ACK sent by DCTCP to reflect ECN */ tcp_dec_quickack_mode(sk, pkts); inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); } /* Determine a window scaling and initial window to offer. * Based on the assumption that the given amount of space * will be offered. Store the results in the tp structure. * NOTE: for smooth operation initial space offering should * be a multiple of mss if possible. We assume here that mss >= 1. * This MUST be enforced by all callers. */ void tcp_select_initial_window(const struct sock *sk, int __space, __u32 mss, __u32 *rcv_wnd, __u32 *window_clamp, int wscale_ok, __u8 *rcv_wscale, __u32 init_rcv_wnd) { unsigned int space = (__space < 0 ? 0 : __space); /* If no clamp set the clamp to the max possible scaled window */ if (*window_clamp == 0) (*window_clamp) = (U16_MAX << TCP_MAX_WSCALE); space = min(*window_clamp, space); /* Quantize space offering to a multiple of mss if possible. */ if (space > mss) space = rounddown(space, mss); /* NOTE: offering an initial window larger than 32767 * will break some buggy TCP stacks. If the admin tells us * it is likely we could be speaking with such a buggy stack * we will truncate our initial window offering to 32K-1 * unless the remote has sent us a window scaling option, * which we interpret as a sign the remote TCP is not * misinterpreting the window field as a signed quantity. */ if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_workaround_signed_windows)) (*rcv_wnd) = min(space, MAX_TCP_WINDOW); else (*rcv_wnd) = min_t(u32, space, U16_MAX); if (init_rcv_wnd) *rcv_wnd = min(*rcv_wnd, init_rcv_wnd * mss); *rcv_wscale = 0; if (wscale_ok) { /* Set window scaling on max possible window */ space = max_t(u32, space, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])); space = max_t(u32, space, READ_ONCE(sysctl_rmem_max)); space = min_t(u32, space, *window_clamp); *rcv_wscale = clamp_t(int, ilog2(space) - 15, 0, TCP_MAX_WSCALE); } /* Set the clamp no higher than max representable value */ (*window_clamp) = min_t(__u32, U16_MAX << (*rcv_wscale), *window_clamp); } EXPORT_SYMBOL(tcp_select_initial_window); /* Chose a new window to advertise, update state in tcp_sock for the * socket, and return result with RFC1323 scaling applied. The return * value can be stuffed directly into th->window for an outgoing * frame. */ static u16 tcp_select_window(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); u32 old_win = tp->rcv_wnd; u32 cur_win, new_win; /* Make the window 0 if we failed to queue the data because we * are out of memory. The window is temporary, so we don't store * it on the socket. */ if (unlikely(inet_csk(sk)->icsk_ack.pending & ICSK_ACK_NOMEM)) return 0; cur_win = tcp_receive_window(tp); new_win = __tcp_select_window(sk); if (new_win < cur_win) { /* Danger Will Robinson! * Don't update rcv_wup/rcv_wnd here or else * we will not be able to advertise a zero * window in time. --DaveM * * Relax Will Robinson. */ if (!READ_ONCE(net->ipv4.sysctl_tcp_shrink_window) || !tp->rx_opt.rcv_wscale) { /* Never shrink the offered window */ if (new_win == 0) NET_INC_STATS(net, LINUX_MIB_TCPWANTZEROWINDOWADV); new_win = ALIGN(cur_win, 1 << tp->rx_opt.rcv_wscale); } } tp->rcv_wnd = new_win; tp->rcv_wup = tp->rcv_nxt; /* Make sure we do not exceed the maximum possible * scaled window. */ if (!tp->rx_opt.rcv_wscale && READ_ONCE(net->ipv4.sysctl_tcp_workaround_signed_windows)) new_win = min(new_win, MAX_TCP_WINDOW); else new_win = min(new_win, (65535U << tp->rx_opt.rcv_wscale)); /* RFC1323 scaling applied */ new_win >>= tp->rx_opt.rcv_wscale; /* If we advertise zero window, disable fast path. */ if (new_win == 0) { tp->pred_flags = 0; if (old_win) NET_INC_STATS(net, LINUX_MIB_TCPTOZEROWINDOWADV); } else if (old_win == 0) { NET_INC_STATS(net, LINUX_MIB_TCPFROMZEROWINDOWADV); } return new_win; } /* Packet ECN state for a SYN-ACK */ static void tcp_ecn_send_synack(struct sock *sk, struct sk_buff *skb) { const struct tcp_sock *tp = tcp_sk(sk); TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_CWR; if (!(tp->ecn_flags & TCP_ECN_OK)) TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_ECE; else if (tcp_ca_needs_ecn(sk) || tcp_bpf_ca_needs_ecn(sk)) INET_ECN_xmit(sk); } /* Packet ECN state for a SYN. */ static void tcp_ecn_send_syn(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); bool bpf_needs_ecn = tcp_bpf_ca_needs_ecn(sk); bool use_ecn = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_ecn) == 1 || tcp_ca_needs_ecn(sk) || bpf_needs_ecn; if (!use_ecn) { const struct dst_entry *dst = __sk_dst_get(sk); if (dst && dst_feature(dst, RTAX_FEATURE_ECN)) use_ecn = true; } tp->ecn_flags = 0; if (use_ecn) { TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_ECE | TCPHDR_CWR; tp->ecn_flags = TCP_ECN_OK; if (tcp_ca_needs_ecn(sk) || bpf_needs_ecn) INET_ECN_xmit(sk); } } static void tcp_ecn_clear_syn(struct sock *sk, struct sk_buff *skb) { if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_ecn_fallback)) /* tp->ecn_flags are cleared at a later point in time when * SYN ACK is ultimatively being received. */ TCP_SKB_CB(skb)->tcp_flags &= ~(TCPHDR_ECE | TCPHDR_CWR); } static void tcp_ecn_make_synack(const struct request_sock *req, struct tcphdr *th) { if (inet_rsk(req)->ecn_ok) th->ece = 1; } /* Set up ECN state for a packet on a ESTABLISHED socket that is about to * be sent. */ static void tcp_ecn_send(struct sock *sk, struct sk_buff *skb, struct tcphdr *th, int tcp_header_len) { struct tcp_sock *tp = tcp_sk(sk); if (tp->ecn_flags & TCP_ECN_OK) { /* Not-retransmitted data segment: set ECT and inject CWR. */ if (skb->len != tcp_header_len && !before(TCP_SKB_CB(skb)->seq, tp->snd_nxt)) { INET_ECN_xmit(sk); if (tp->ecn_flags & TCP_ECN_QUEUE_CWR) { tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR; th->cwr = 1; skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; } } else if (!tcp_ca_needs_ecn(sk)) { /* ACK or retransmitted segment: clear ECT|CE */ INET_ECN_dontxmit(sk); } if (tp->ecn_flags & TCP_ECN_DEMAND_CWR) th->ece = 1; } } /* Constructs common control bits of non-data skb. If SYN/FIN is present, * auto increment end seqno. */ static void tcp_init_nondata_skb(struct sk_buff *skb, u32 seq, u8 flags) { skb->ip_summed = CHECKSUM_PARTIAL; TCP_SKB_CB(skb)->tcp_flags = flags; tcp_skb_pcount_set(skb, 1); TCP_SKB_CB(skb)->seq = seq; if (flags & (TCPHDR_SYN | TCPHDR_FIN)) seq++; TCP_SKB_CB(skb)->end_seq = seq; } static inline bool tcp_urg_mode(const struct tcp_sock *tp) { return tp->snd_una != tp->snd_up; } #define OPTION_SACK_ADVERTISE BIT(0) #define OPTION_TS BIT(1) #define OPTION_MD5 BIT(2) #define OPTION_WSCALE BIT(3) #define OPTION_FAST_OPEN_COOKIE BIT(8) #define OPTION_SMC BIT(9) #define OPTION_MPTCP BIT(10) static void smc_options_write(__be32 *ptr, u16 *options) { #if IS_ENABLED(CONFIG_SMC) if (static_branch_unlikely(&tcp_have_smc)) { if (unlikely(OPTION_SMC & *options)) { *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_EXP << 8) | (TCPOLEN_EXP_SMC_BASE)); *ptr++ = htonl(TCPOPT_SMC_MAGIC); } } #endif } struct tcp_out_options { u16 options; /* bit field of OPTION_* */ u16 mss; /* 0 to disable */ u8 ws; /* window scale, 0 to disable */ u8 num_sack_blocks; /* number of SACK blocks to include */ u8 hash_size; /* bytes in hash_location */ u8 bpf_opt_len; /* length of BPF hdr option */ __u8 *hash_location; /* temporary pointer, overloaded */ __u32 tsval, tsecr; /* need to include OPTION_TS */ struct tcp_fastopen_cookie *fastopen_cookie; /* Fast open cookie */ struct mptcp_out_options mptcp; }; static void mptcp_options_write(struct tcphdr *th, __be32 *ptr, struct tcp_sock *tp, struct tcp_out_options *opts) { #if IS_ENABLED(CONFIG_MPTCP) if (unlikely(OPTION_MPTCP & opts->options)) mptcp_write_options(th, ptr, tp, &opts->mptcp); #endif } #ifdef CONFIG_CGROUP_BPF static int bpf_skops_write_hdr_opt_arg0(struct sk_buff *skb, enum tcp_synack_type synack_type) { if (unlikely(!skb)) return BPF_WRITE_HDR_TCP_CURRENT_MSS; if (unlikely(synack_type == TCP_SYNACK_COOKIE)) return BPF_WRITE_HDR_TCP_SYNACK_COOKIE; return 0; } /* req, syn_skb and synack_type are used when writing synack */ static void bpf_skops_hdr_opt_len(struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct sk_buff *syn_skb, enum tcp_synack_type synack_type, struct tcp_out_options *opts, unsigned int *remaining) { struct bpf_sock_ops_kern sock_ops; int err; if (likely(!BPF_SOCK_OPS_TEST_FLAG(tcp_sk(sk), BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG)) || !*remaining) return; /* *remaining has already been aligned to 4 bytes, so *remaining >= 4 */ /* init sock_ops */ memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp)); sock_ops.op = BPF_SOCK_OPS_HDR_OPT_LEN_CB; if (req) { /* The listen "sk" cannot be passed here because * it is not locked. It would not make too much * sense to do bpf_setsockopt(listen_sk) based * on individual connection request also. * * Thus, "req" is passed here and the cgroup-bpf-progs * of the listen "sk" will be run. * * "req" is also used here for fastopen even the "sk" here is * a fullsock "child" sk. It is to keep the behavior * consistent between fastopen and non-fastopen on * the bpf programming side. */ sock_ops.sk = (struct sock *)req; sock_ops.syn_skb = syn_skb; } else { sock_owned_by_me(sk); sock_ops.is_fullsock = 1; sock_ops.sk = sk; } sock_ops.args[0] = bpf_skops_write_hdr_opt_arg0(skb, synack_type); sock_ops.remaining_opt_len = *remaining; /* tcp_current_mss() does not pass a skb */ if (skb) bpf_skops_init_skb(&sock_ops, skb, 0); err = BPF_CGROUP_RUN_PROG_SOCK_OPS_SK(&sock_ops, sk); if (err || sock_ops.remaining_opt_len == *remaining) return; opts->bpf_opt_len = *remaining - sock_ops.remaining_opt_len; /* round up to 4 bytes */ opts->bpf_opt_len = (opts->bpf_opt_len + 3) & ~3; *remaining -= opts->bpf_opt_len; } static void bpf_skops_write_hdr_opt(struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct sk_buff *syn_skb, enum tcp_synack_type synack_type, struct tcp_out_options *opts) { u8 first_opt_off, nr_written, max_opt_len = opts->bpf_opt_len; struct bpf_sock_ops_kern sock_ops; int err; if (likely(!max_opt_len)) return; memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp)); sock_ops.op = BPF_SOCK_OPS_WRITE_HDR_OPT_CB; if (req) { sock_ops.sk = (struct sock *)req; sock_ops.syn_skb = syn_skb; } else { sock_owned_by_me(sk); sock_ops.is_fullsock = 1; sock_ops.sk = sk; } sock_ops.args[0] = bpf_skops_write_hdr_opt_arg0(skb, synack_type); sock_ops.remaining_opt_len = max_opt_len; first_opt_off = tcp_hdrlen(skb) - max_opt_len; bpf_skops_init_skb(&sock_ops, skb, first_opt_off); err = BPF_CGROUP_RUN_PROG_SOCK_OPS_SK(&sock_ops, sk); if (err) nr_written = 0; else nr_written = max_opt_len - sock_ops.remaining_opt_len; if (nr_written < max_opt_len) memset(skb->data + first_opt_off + nr_written, TCPOPT_NOP, max_opt_len - nr_written); } #else static void bpf_skops_hdr_opt_len(struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct sk_buff *syn_skb, enum tcp_synack_type synack_type, struct tcp_out_options *opts, unsigned int *remaining) { } static void bpf_skops_write_hdr_opt(struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct sk_buff *syn_skb, enum tcp_synack_type synack_type, struct tcp_out_options *opts) { } #endif /* Write previously computed TCP options to the packet. * * Beware: Something in the Internet is very sensitive to the ordering of * TCP options, we learned this through the hard way, so be careful here. * Luckily we can at least blame others for their non-compliance but from * inter-operability perspective it seems that we're somewhat stuck with * the ordering which we have been using if we want to keep working with * those broken things (not that it currently hurts anybody as there isn't * particular reason why the ordering would need to be changed). * * At least SACK_PERM as the first option is known to lead to a disaster * (but it may well be that other scenarios fail similarly). */ static void tcp_options_write(struct tcphdr *th, struct tcp_sock *tp, struct tcp_out_options *opts) { __be32 *ptr = (__be32 *)(th + 1); u16 options = opts->options; /* mungable copy */ if (unlikely(OPTION_MD5 & options)) { *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); /* overload cookie hash location */ opts->hash_location = (__u8 *)ptr; ptr += 4; } if (unlikely(opts->mss)) { *ptr++ = htonl((TCPOPT_MSS << 24) | (TCPOLEN_MSS << 16) | opts->mss); } if (likely(OPTION_TS & options)) { if (unlikely(OPTION_SACK_ADVERTISE & options)) { *ptr++ = htonl((TCPOPT_SACK_PERM << 24) | (TCPOLEN_SACK_PERM << 16) | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); options &= ~OPTION_SACK_ADVERTISE; } else { *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); } *ptr++ = htonl(opts->tsval); *ptr++ = htonl(opts->tsecr); } if (unlikely(OPTION_SACK_ADVERTISE & options)) { *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_SACK_PERM << 8) | TCPOLEN_SACK_PERM); } if (unlikely(OPTION_WSCALE & options)) { *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_WINDOW << 16) | (TCPOLEN_WINDOW << 8) | opts->ws); } if (unlikely(opts->num_sack_blocks)) { struct tcp_sack_block *sp = tp->rx_opt.dsack ? tp->duplicate_sack : tp->selective_acks; int this_sack; *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_SACK << 8) | (TCPOLEN_SACK_BASE + (opts->num_sack_blocks * TCPOLEN_SACK_PERBLOCK))); for (this_sack = 0; this_sack < opts->num_sack_blocks; ++this_sack) { *ptr++ = htonl(sp[this_sack].start_seq); *ptr++ = htonl(sp[this_sack].end_seq); } tp->rx_opt.dsack = 0; } if (unlikely(OPTION_FAST_OPEN_COOKIE & options)) { struct tcp_fastopen_cookie *foc = opts->fastopen_cookie; u8 *p = (u8 *)ptr; u32 len; /* Fast Open option length */ if (foc->exp) { len = TCPOLEN_EXP_FASTOPEN_BASE + foc->len; *ptr = htonl((TCPOPT_EXP << 24) | (len << 16) | TCPOPT_FASTOPEN_MAGIC); p += TCPOLEN_EXP_FASTOPEN_BASE; } else { len = TCPOLEN_FASTOPEN_BASE + foc->len; *p++ = TCPOPT_FASTOPEN; *p++ = len; } memcpy(p, foc->val, foc->len); if ((len & 3) == 2) { p[foc->len] = TCPOPT_NOP; p[foc->len + 1] = TCPOPT_NOP; } ptr += (len + 3) >> 2; } smc_options_write(ptr, &options); mptcp_options_write(th, ptr, tp, opts); } static void smc_set_option(const struct tcp_sock *tp, struct tcp_out_options *opts, unsigned int *remaining) { #if IS_ENABLED(CONFIG_SMC) if (static_branch_unlikely(&tcp_have_smc)) { if (tp->syn_smc) { if (*remaining >= TCPOLEN_EXP_SMC_BASE_ALIGNED) { opts->options |= OPTION_SMC; *remaining -= TCPOLEN_EXP_SMC_BASE_ALIGNED; } } } #endif } static void smc_set_option_cond(const struct tcp_sock *tp, const struct inet_request_sock *ireq, struct tcp_out_options *opts, unsigned int *remaining) { #if IS_ENABLED(CONFIG_SMC) if (static_branch_unlikely(&tcp_have_smc)) { if (tp->syn_smc && ireq->smc_ok) { if (*remaining >= TCPOLEN_EXP_SMC_BASE_ALIGNED) { opts->options |= OPTION_SMC; *remaining -= TCPOLEN_EXP_SMC_BASE_ALIGNED; } } } #endif } static void mptcp_set_option_cond(const struct request_sock *req, struct tcp_out_options *opts, unsigned int *remaining) { if (rsk_is_mptcp(req)) { unsigned int size; if (mptcp_synack_options(req, &size, &opts->mptcp)) { if (*remaining >= size) { opts->options |= OPTION_MPTCP; *remaining -= size; } } } } /* Compute TCP options for SYN packets. This is not the final * network wire format yet. */ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb, struct tcp_out_options *opts, struct tcp_md5sig_key **md5) { struct tcp_sock *tp = tcp_sk(sk); unsigned int remaining = MAX_TCP_OPTION_SPACE; struct tcp_fastopen_request *fastopen = tp->fastopen_req; *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG if (static_branch_unlikely(&tcp_md5_needed.key) && rcu_access_pointer(tp->md5sig_info)) { *md5 = tp->af_specific->md5_lookup(sk, sk); if (*md5) { opts->options |= OPTION_MD5; remaining -= TCPOLEN_MD5SIG_ALIGNED; } } #endif /* We always get an MSS option. The option bytes which will be seen in * normal data packets should timestamps be used, must be in the MSS * advertised. But we subtract them from tp->mss_cache so that * calculations in tcp_sendmsg are simpler etc. So account for this * fact here if necessary. If we don't do this correctly, as a * receiver we won't recognize data packets as being full sized when we * should, and thus we won't abide by the delayed ACK rules correctly. * SACKs don't matter, we never delay an ACK when we have any of those * going out. */ opts->mss = tcp_advertise_mss(sk); remaining -= TCPOLEN_MSS_ALIGNED; if (likely(READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_timestamps) && !*md5)) { opts->options |= OPTION_TS; opts->tsval = tcp_skb_timestamp(skb) + tp->tsoffset; opts->tsecr = tp->rx_opt.ts_recent; remaining -= TCPOLEN_TSTAMP_ALIGNED; } if (likely(READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_window_scaling))) { opts->ws = tp->rx_opt.rcv_wscale; opts->options |= OPTION_WSCALE; remaining -= TCPOLEN_WSCALE_ALIGNED; } if (likely(READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_sack))) { opts->options |= OPTION_SACK_ADVERTISE; if (unlikely(!(OPTION_TS & opts->options))) remaining -= TCPOLEN_SACKPERM_ALIGNED; } if (fastopen && fastopen->cookie.len >= 0) { u32 need = fastopen->cookie.len; need += fastopen->cookie.exp ? TCPOLEN_EXP_FASTOPEN_BASE : TCPOLEN_FASTOPEN_BASE; need = (need + 3) & ~3U; /* Align to 32 bits */ if (remaining >= need) { opts->options |= OPTION_FAST_OPEN_COOKIE; opts->fastopen_cookie = &fastopen->cookie; remaining -= need; tp->syn_fastopen = 1; tp->syn_fastopen_exp = fastopen->cookie.exp ? 1 : 0; } } smc_set_option(tp, opts, &remaining); if (sk_is_mptcp(sk)) { unsigned int size; if (mptcp_syn_options(sk, skb, &size, &opts->mptcp)) { opts->options |= OPTION_MPTCP; remaining -= size; } } bpf_skops_hdr_opt_len(sk, skb, NULL, NULL, 0, opts, &remaining); return MAX_TCP_OPTION_SPACE - remaining; } /* Set up TCP options for SYN-ACKs. */ static unsigned int tcp_synack_options(const struct sock *sk, struct request_sock *req, unsigned int mss, struct sk_buff *skb, struct tcp_out_options *opts, const struct tcp_md5sig_key *md5, struct tcp_fastopen_cookie *foc, enum tcp_synack_type synack_type, struct sk_buff *syn_skb) { struct inet_request_sock *ireq = inet_rsk(req); unsigned int remaining = MAX_TCP_OPTION_SPACE; #ifdef CONFIG_TCP_MD5SIG if (md5) { opts->options |= OPTION_MD5; remaining -= TCPOLEN_MD5SIG_ALIGNED; /* We can't fit any SACK blocks in a packet with MD5 + TS * options. There was discussion about disabling SACK * rather than TS in order to fit in better with old, * buggy kernels, but that was deemed to be unnecessary. */ if (synack_type != TCP_SYNACK_COOKIE) ireq->tstamp_ok &= !ireq->sack_ok; } #endif /* We always send an MSS option. */ opts->mss = mss; remaining -= TCPOLEN_MSS_ALIGNED; if (likely(ireq->wscale_ok)) { opts->ws = ireq->rcv_wscale; opts->options |= OPTION_WSCALE; remaining -= TCPOLEN_WSCALE_ALIGNED; } if (likely(ireq->tstamp_ok)) { opts->options |= OPTION_TS; opts->tsval = tcp_skb_timestamp(skb) + tcp_rsk(req)->ts_off; opts->tsecr = READ_ONCE(req->ts_recent); remaining -= TCPOLEN_TSTAMP_ALIGNED; } if (likely(ireq->sack_ok)) { opts->options |= OPTION_SACK_ADVERTISE; if (unlikely(!ireq->tstamp_ok)) remaining -= TCPOLEN_SACKPERM_ALIGNED; } if (foc != NULL && foc->len >= 0) { u32 need = foc->len; need += foc->exp ? TCPOLEN_EXP_FASTOPEN_BASE : TCPOLEN_FASTOPEN_BASE; need = (need + 3) & ~3U; /* Align to 32 bits */ if (remaining >= need) { opts->options |= OPTION_FAST_OPEN_COOKIE; opts->fastopen_cookie = foc; remaining -= need; } } mptcp_set_option_cond(req, opts, &remaining); smc_set_option_cond(tcp_sk(sk), ireq, opts, &remaining); bpf_skops_hdr_opt_len((struct sock *)sk, skb, req, syn_skb, synack_type, opts, &remaining); return MAX_TCP_OPTION_SPACE - remaining; } /* Compute TCP options for ESTABLISHED sockets. This is not the * final wire format yet. */ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb, struct tcp_out_options *opts, struct tcp_md5sig_key **md5) { struct tcp_sock *tp = tcp_sk(sk); unsigned int size = 0; unsigned int eff_sacks; opts->options = 0; *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG if (static_branch_unlikely(&tcp_md5_needed.key) && rcu_access_pointer(tp->md5sig_info)) { *md5 = tp->af_specific->md5_lookup(sk, sk); if (*md5) { opts->options |= OPTION_MD5; size += TCPOLEN_MD5SIG_ALIGNED; } } #endif if (likely(tp->rx_opt.tstamp_ok)) { opts->options |= OPTION_TS; opts->tsval = skb ? tcp_skb_timestamp(skb) + tp->tsoffset : 0; opts->tsecr = tp->rx_opt.ts_recent; size += TCPOLEN_TSTAMP_ALIGNED; } /* MPTCP options have precedence over SACK for the limited TCP * option space because a MPTCP connection would be forced to * fall back to regular TCP if a required multipath option is * missing. SACK still gets a chance to use whatever space is * left. */ if (sk_is_mptcp(sk)) { unsigned int remaining = MAX_TCP_OPTION_SPACE - size; unsigned int opt_size = 0; if (mptcp_established_options(sk, skb, &opt_size, remaining, &opts->mptcp)) { opts->options |= OPTION_MPTCP; size += opt_size; } } eff_sacks = tp->rx_opt.num_sacks + tp->rx_opt.dsack; if (unlikely(eff_sacks)) { const unsigned int remaining = MAX_TCP_OPTION_SPACE - size; if (unlikely(remaining < TCPOLEN_SACK_BASE_ALIGNED + TCPOLEN_SACK_PERBLOCK)) return size; opts->num_sack_blocks = min_t(unsigned int, eff_sacks, (remaining - TCPOLEN_SACK_BASE_ALIGNED) / TCPOLEN_SACK_PERBLOCK); size += TCPOLEN_SACK_BASE_ALIGNED + opts->num_sack_blocks * TCPOLEN_SACK_PERBLOCK; } if (unlikely(BPF_SOCK_OPS_TEST_FLAG(tp, BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG))) { unsigned int remaining = MAX_TCP_OPTION_SPACE - size; bpf_skops_hdr_opt_len(sk, skb, NULL, NULL, 0, opts, &remaining); size = MAX_TCP_OPTION_SPACE - remaining; } return size; } /* TCP SMALL QUEUES (TSQ) * * TSQ goal is to keep small amount of skbs per tcp flow in tx queues (qdisc+dev) * to reduce RTT and bufferbloat. * We do this using a special skb destructor (tcp_wfree). * * Its important tcp_wfree() can be replaced by sock_wfree() in the event skb * needs to be reallocated in a driver. * The invariant being skb->truesize subtracted from sk->sk_wmem_alloc * * Since transmit from skb destructor is forbidden, we use a tasklet * to process all sockets that eventually need to send more skbs. * We use one tasklet per cpu, with its own queue of sockets. */ struct tsq_tasklet { struct tasklet_struct tasklet; struct list_head head; /* queue of tcp sockets */ }; static DEFINE_PER_CPU(struct tsq_tasklet, tsq_tasklet); static void tcp_tsq_write(struct sock *sk) { if ((1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_CLOSING | TCPF_CLOSE_WAIT | TCPF_LAST_ACK)) { struct tcp_sock *tp = tcp_sk(sk); if (tp->lost_out > tp->retrans_out && tcp_snd_cwnd(tp) > tcp_packets_in_flight(tp)) { tcp_mstamp_refresh(tp); tcp_xmit_retransmit_queue(sk); } tcp_write_xmit(sk, tcp_current_mss(sk), tp->nonagle, 0, GFP_ATOMIC); } } static void tcp_tsq_handler(struct sock *sk) { bh_lock_sock(sk); if (!sock_owned_by_user(sk)) tcp_tsq_write(sk); else if (!test_and_set_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags)) sock_hold(sk); bh_unlock_sock(sk); } /* * One tasklet per cpu tries to send more skbs. * We run in tasklet context but need to disable irqs when * transferring tsq->head because tcp_wfree() might * interrupt us (non NAPI drivers) */ static void tcp_tasklet_func(struct tasklet_struct *t) { struct tsq_tasklet *tsq = from_tasklet(tsq, t, tasklet); LIST_HEAD(list); unsigned long flags; struct list_head *q, *n; struct tcp_sock *tp; struct sock *sk; local_irq_save(flags); list_splice_init(&tsq->head, &list); local_irq_restore(flags); list_for_each_safe(q, n, &list) { tp = list_entry(q, struct tcp_sock, tsq_node); list_del(&tp->tsq_node); sk = (struct sock *)tp; smp_mb__before_atomic(); clear_bit(TSQ_QUEUED, &sk->sk_tsq_flags); tcp_tsq_handler(sk); sk_free(sk); } } #define TCP_DEFERRED_ALL (TCPF_TSQ_DEFERRED | \ TCPF_WRITE_TIMER_DEFERRED | \ TCPF_DELACK_TIMER_DEFERRED | \ TCPF_MTU_REDUCED_DEFERRED) /** * tcp_release_cb - tcp release_sock() callback * @sk: socket * * called from release_sock() to perform protocol dependent * actions before socket release. */ void tcp_release_cb(struct sock *sk) { unsigned long flags = smp_load_acquire(&sk->sk_tsq_flags); unsigned long nflags; /* perform an atomic operation only if at least one flag is set */ do { if (!(flags & TCP_DEFERRED_ALL)) return; nflags = flags & ~TCP_DEFERRED_ALL; } while (!try_cmpxchg(&sk->sk_tsq_flags, &flags, nflags)); if (flags & TCPF_TSQ_DEFERRED) { tcp_tsq_write(sk); __sock_put(sk); } /* Here begins the tricky part : * We are called from release_sock() with : * 1) BH disabled * 2) sk_lock.slock spinlock held * 3) socket owned by us (sk->sk_lock.owned == 1) * * But following code is meant to be called from BH handlers, * so we should keep BH disabled, but early release socket ownership */ sock_release_ownership(sk); if (flags & TCPF_WRITE_TIMER_DEFERRED) { tcp_write_timer_handler(sk); __sock_put(sk); } if (flags & TCPF_DELACK_TIMER_DEFERRED) { tcp_delack_timer_handler(sk); __sock_put(sk); } if (flags & TCPF_MTU_REDUCED_DEFERRED) { inet_csk(sk)->icsk_af_ops->mtu_reduced(sk); __sock_put(sk); } } EXPORT_SYMBOL(tcp_release_cb); void __init tcp_tasklet_init(void) { int i; for_each_possible_cpu(i) { struct tsq_tasklet *tsq = &per_cpu(tsq_tasklet, i); INIT_LIST_HEAD(&tsq->head); tasklet_setup(&tsq->tasklet, tcp_tasklet_func); } } /* * Write buffer destructor automatically called from kfree_skb. * We can't xmit new skbs from this context, as we might already * hold qdisc lock. */ void tcp_wfree(struct sk_buff *skb) { struct sock *sk = skb->sk; struct tcp_sock *tp = tcp_sk(sk); unsigned long flags, nval, oval; struct tsq_tasklet *tsq; bool empty; /* Keep one reference on sk_wmem_alloc. * Will be released by sk_free() from here or tcp_tasklet_func() */ WARN_ON(refcount_sub_and_test(skb->truesize - 1, &sk->sk_wmem_alloc)); /* If this softirq is serviced by ksoftirqd, we are likely under stress. * Wait until our queues (qdisc + devices) are drained. * This gives : * - less callbacks to tcp_write_xmit(), reducing stress (batches) * - chance for incoming ACK (processed by another cpu maybe) * to migrate this flow (skb->ooo_okay will be eventually set) */ if (refcount_read(&sk->sk_wmem_alloc) >= SKB_TRUESIZE(1) && this_cpu_ksoftirqd() == current) goto out; oval = smp_load_acquire(&sk->sk_tsq_flags); do { if (!(oval & TSQF_THROTTLED) || (oval & TSQF_QUEUED)) goto out; nval = (oval & ~TSQF_THROTTLED) | TSQF_QUEUED; } while (!try_cmpxchg(&sk->sk_tsq_flags, &oval, nval)); /* queue this socket to tasklet queue */ local_irq_save(flags); tsq = this_cpu_ptr(&tsq_tasklet); empty = list_empty(&tsq->head); list_add(&tp->tsq_node, &tsq->head); if (empty) tasklet_schedule(&tsq->tasklet); local_irq_restore(flags); return; out: sk_free(sk); } /* Note: Called under soft irq. * We can call TCP stack right away, unless socket is owned by user. */ enum hrtimer_restart tcp_pace_kick(struct hrtimer *timer) { struct tcp_sock *tp = container_of(timer, struct tcp_sock, pacing_timer); struct sock *sk = (struct sock *)tp; tcp_tsq_handler(sk); sock_put(sk); return HRTIMER_NORESTART; } static void tcp_update_skb_after_send(struct sock *sk, struct sk_buff *skb, u64 prior_wstamp) { struct tcp_sock *tp = tcp_sk(sk); if (sk->sk_pacing_status != SK_PACING_NONE) { unsigned long rate = sk->sk_pacing_rate; /* Original sch_fq does not pace first 10 MSS * Note that tp->data_segs_out overflows after 2^32 packets, * this is a minor annoyance. */ if (rate != ~0UL && rate && tp->data_segs_out >= 10) { u64 len_ns = div64_ul((u64)skb->len * NSEC_PER_SEC, rate); u64 credit = tp->tcp_wstamp_ns - prior_wstamp; /* take into account OS jitter */ len_ns -= min_t(u64, len_ns / 2, credit); tp->tcp_wstamp_ns += len_ns; } } list_move_tail(&skb->tcp_tsorted_anchor, &tp->tsorted_sent_queue); } INDIRECT_CALLABLE_DECLARE(int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl)); INDIRECT_CALLABLE_DECLARE(int inet6_csk_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl)); INDIRECT_CALLABLE_DECLARE(void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb)); /* This routine actually transmits TCP packets queued in by * tcp_do_sendmsg(). This is used by both the initial * transmission and possible later retransmissions. * All SKB's seen here are completely headerless. It is our * job to build the TCP header, and pass the packet down to * IP so it can do the same plus pass the packet off to the * device. * * We are working here with either a clone of the original * SKB, or a fresh unique copy made by the retransmit engine. */ static int __tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, gfp_t gfp_mask, u32 rcv_nxt) { const struct inet_connection_sock *icsk = inet_csk(sk); struct inet_sock *inet; struct tcp_sock *tp; struct tcp_skb_cb *tcb; struct tcp_out_options opts; unsigned int tcp_options_size, tcp_header_size; struct sk_buff *oskb = NULL; struct tcp_md5sig_key *md5; struct tcphdr *th; u64 prior_wstamp; int err; BUG_ON(!skb || !tcp_skb_pcount(skb)); tp = tcp_sk(sk); prior_wstamp = tp->tcp_wstamp_ns; tp->tcp_wstamp_ns = max(tp->tcp_wstamp_ns, tp->tcp_clock_cache); skb_set_delivery_time(skb, tp->tcp_wstamp_ns, true); if (clone_it) { oskb = skb; tcp_skb_tsorted_save(oskb) { if (unlikely(skb_cloned(oskb))) skb = pskb_copy(oskb, gfp_mask); else skb = skb_clone(oskb, gfp_mask); } tcp_skb_tsorted_restore(oskb); if (unlikely(!skb)) return -ENOBUFS; /* retransmit skbs might have a non zero value in skb->dev * because skb->dev is aliased with skb->rbnode.rb_left */ skb->dev = NULL; } inet = inet_sk(sk); tcb = TCP_SKB_CB(skb); memset(&opts, 0, sizeof(opts)); if (unlikely(tcb->tcp_flags & TCPHDR_SYN)) { tcp_options_size = tcp_syn_options(sk, skb, &opts, &md5); } else { tcp_options_size = tcp_established_options(sk, skb, &opts, &md5); /* Force a PSH flag on all (GSO) packets to expedite GRO flush * at receiver : This slightly improve GRO performance. * Note that we do not force the PSH flag for non GSO packets, * because they might be sent under high congestion events, * and in this case it is better to delay the delivery of 1-MSS * packets and thus the corresponding ACK packet that would * release the following packet. */ if (tcp_skb_pcount(skb) > 1) tcb->tcp_flags |= TCPHDR_PSH; } tcp_header_size = tcp_options_size + sizeof(struct tcphdr); /* We set skb->ooo_okay to one if this packet can select * a different TX queue than prior packets of this flow, * to avoid self inflicted reorders. * The 'other' queue decision is based on current cpu number * if XPS is enabled, or sk->sk_txhash otherwise. * We can switch to another (and better) queue if: * 1) No packet with payload is in qdisc/device queues. * Delays in TX completion can defeat the test * even if packets were already sent. * 2) Or rtx queue is empty. * This mitigates above case if ACK packets for * all prior packets were already processed. */ skb->ooo_okay = sk_wmem_alloc_get(sk) < SKB_TRUESIZE(1) || tcp_rtx_queue_empty(sk); /* If we had to use memory reserve to allocate this skb, * this might cause drops if packet is looped back : * Other socket might not have SOCK_MEMALLOC. * Packets not looped back do not care about pfmemalloc. */ skb->pfmemalloc = 0; skb_push(skb, tcp_header_size); skb_reset_transport_header(skb); skb_orphan(skb); skb->sk = sk; skb->destructor = skb_is_tcp_pure_ack(skb) ? __sock_wfree : tcp_wfree; refcount_add(skb->truesize, &sk->sk_wmem_alloc); skb_set_dst_pending_confirm(skb, sk->sk_dst_pending_confirm); /* Build TCP header and checksum it. */ th = (struct tcphdr *)skb->data; th->source = inet->inet_sport; th->dest = inet->inet_dport; th->seq = htonl(tcb->seq); th->ack_seq = htonl(rcv_nxt); *(((__be16 *)th) + 6) = htons(((tcp_header_size >> 2) << 12) | tcb->tcp_flags); th->check = 0; th->urg_ptr = 0; /* The urg_mode check is necessary during a below snd_una win probe */ if (unlikely(tcp_urg_mode(tp) && before(tcb->seq, tp->snd_up))) { if (before(tp->snd_up, tcb->seq + 0x10000)) { th->urg_ptr = htons(tp->snd_up - tcb->seq); th->urg = 1; } else if (after(tcb->seq + 0xFFFF, tp->snd_nxt)) { th->urg_ptr = htons(0xFFFF); th->urg = 1; } } skb_shinfo(skb)->gso_type = sk->sk_gso_type; if (likely(!(tcb->tcp_flags & TCPHDR_SYN))) { th->window = htons(tcp_select_window(sk)); tcp_ecn_send(sk, skb, th, tcp_header_size); } else { /* RFC1323: The window in SYN & SYN/ACK segments * is never scaled. */ th->window = htons(min(tp->rcv_wnd, 65535U)); } tcp_options_write(th, tp, &opts); #ifdef CONFIG_TCP_MD5SIG /* Calculate the MD5 hash, as we have all we need now */ if (md5) { sk_gso_disable(sk); tp->af_specific->calc_md5_hash(opts.hash_location, md5, sk, skb); } #endif /* BPF prog is the last one writing header option */ bpf_skops_write_hdr_opt(sk, skb, NULL, NULL, 0, &opts); INDIRECT_CALL_INET(icsk->icsk_af_ops->send_check, tcp_v6_send_check, tcp_v4_send_check, sk, skb); if (likely(tcb->tcp_flags & TCPHDR_ACK)) tcp_event_ack_sent(sk, tcp_skb_pcount(skb), rcv_nxt); if (skb->len != tcp_header_size) { tcp_event_data_sent(tp, sk); tp->data_segs_out += tcp_skb_pcount(skb); tp->bytes_sent += skb->len - tcp_header_size; } if (after(tcb->end_seq, tp->snd_nxt) || tcb->seq == tcb->end_seq) TCP_ADD_STATS(sock_net(sk), TCP_MIB_OUTSEGS, tcp_skb_pcount(skb)); tp->segs_out += tcp_skb_pcount(skb); skb_set_hash_from_sk(skb, sk); /* OK, its time to fill skb_shinfo(skb)->gso_{segs|size} */ skb_shinfo(skb)->gso_segs = tcp_skb_pcount(skb); skb_shinfo(skb)->gso_size = tcp_skb_mss(skb); /* Leave earliest departure time in skb->tstamp (skb->skb_mstamp_ns) */ /* Cleanup our debris for IP stacks */ memset(skb->cb, 0, max(sizeof(struct inet_skb_parm), sizeof(struct inet6_skb_parm))); tcp_add_tx_delay(skb, tp); err = INDIRECT_CALL_INET(icsk->icsk_af_ops->queue_xmit, inet6_csk_xmit, ip_queue_xmit, sk, skb, &inet->cork.fl); if (unlikely(err > 0)) { tcp_enter_cwr(sk); err = net_xmit_eval(err); } if (!err && oskb) { tcp_update_skb_after_send(sk, oskb, prior_wstamp); tcp_rate_skb_sent(sk, oskb); } return err; } static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, gfp_t gfp_mask) { return __tcp_transmit_skb(sk, skb, clone_it, gfp_mask, tcp_sk(sk)->rcv_nxt); } /* This routine just queues the buffer for sending. * * NOTE: probe0 timer is not checked, do not forget tcp_push_pending_frames, * otherwise socket can stall. */ static void tcp_queue_skb(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); /* Advance write_seq and place onto the write_queue. */ WRITE_ONCE(tp->write_seq, TCP_SKB_CB(skb)->end_seq); __skb_header_release(skb); tcp_add_write_queue_tail(sk, skb); sk_wmem_queued_add(sk, skb->truesize); sk_mem_charge(sk, skb->truesize); } /* Initialize TSO segments for a packet. */ static void tcp_set_skb_tso_segs(struct sk_buff *skb, unsigned int mss_now) { if (skb->len <= mss_now) { /* Avoid the costly divide in the normal * non-TSO case. */ tcp_skb_pcount_set(skb, 1); TCP_SKB_CB(skb)->tcp_gso_size = 0; } else { tcp_skb_pcount_set(skb, DIV_ROUND_UP(skb->len, mss_now)); TCP_SKB_CB(skb)->tcp_gso_size = mss_now; } } /* Pcount in the middle of the write queue got changed, we need to do various * tweaks to fix counters */ static void tcp_adjust_pcount(struct sock *sk, const struct sk_buff *skb, int decr) { struct tcp_sock *tp = tcp_sk(sk); tp->packets_out -= decr; if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) tp->sacked_out -= decr; if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) tp->retrans_out -= decr; if (TCP_SKB_CB(skb)->sacked & TCPCB_LOST) tp->lost_out -= decr; /* Reno case is special. Sigh... */ if (tcp_is_reno(tp) && decr > 0) tp->sacked_out -= min_t(u32, tp->sacked_out, decr); if (tp->lost_skb_hint && before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(tp->lost_skb_hint)->seq) && (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)) tp->lost_cnt_hint -= decr; tcp_verify_left_out(tp); } static bool tcp_has_tx_tstamp(const struct sk_buff *skb) { return TCP_SKB_CB(skb)->txstamp_ack || (skb_shinfo(skb)->tx_flags & SKBTX_ANY_TSTAMP); } static void tcp_fragment_tstamp(struct sk_buff *skb, struct sk_buff *skb2) { struct skb_shared_info *shinfo = skb_shinfo(skb); if (unlikely(tcp_has_tx_tstamp(skb)) && !before(shinfo->tskey, TCP_SKB_CB(skb2)->seq)) { struct skb_shared_info *shinfo2 = skb_shinfo(skb2); u8 tsflags = shinfo->tx_flags & SKBTX_ANY_TSTAMP; shinfo->tx_flags &= ~tsflags; shinfo2->tx_flags |= tsflags; swap(shinfo->tskey, shinfo2->tskey); TCP_SKB_CB(skb2)->txstamp_ack = TCP_SKB_CB(skb)->txstamp_ack; TCP_SKB_CB(skb)->txstamp_ack = 0; } } static void tcp_skb_fragment_eor(struct sk_buff *skb, struct sk_buff *skb2) { TCP_SKB_CB(skb2)->eor = TCP_SKB_CB(skb)->eor; TCP_SKB_CB(skb)->eor = 0; } /* Insert buff after skb on the write or rtx queue of sk. */ static void tcp_insert_write_queue_after(struct sk_buff *skb, struct sk_buff *buff, struct sock *sk, enum tcp_queue tcp_queue) { if (tcp_queue == TCP_FRAG_IN_WRITE_QUEUE) __skb_queue_after(&sk->sk_write_queue, skb, buff); else tcp_rbtree_insert(&sk->tcp_rtx_queue, buff); } /* Function to create two new TCP segments. Shrinks the given segment * to the specified size and appends a new segment with the rest of the * packet to the list. This won't be called frequently, I hope. * Remember, these are still headerless SKBs at this point. */ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue, struct sk_buff *skb, u32 len, unsigned int mss_now, gfp_t gfp) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *buff; int old_factor; long limit; int nlen; u8 flags; if (WARN_ON(len > skb->len)) return -EINVAL; DEBUG_NET_WARN_ON_ONCE(skb_headlen(skb)); /* tcp_sendmsg() can overshoot sk_wmem_queued by one full size skb. * We need some allowance to not penalize applications setting small * SO_SNDBUF values. * Also allow first and last skb in retransmit queue to be split. */ limit = sk->sk_sndbuf + 2 * SKB_TRUESIZE(GSO_LEGACY_MAX_SIZE); if (unlikely((sk->sk_wmem_queued >> 1) > limit && tcp_queue != TCP_FRAG_IN_WRITE_QUEUE && skb != tcp_rtx_queue_head(sk) && skb != tcp_rtx_queue_tail(sk))) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPWQUEUETOOBIG); return -ENOMEM; } if (skb_unclone_keeptruesize(skb, gfp)) return -ENOMEM; /* Get a new skb... force flag on. */ buff = tcp_stream_alloc_skb(sk, gfp, true); if (!buff) return -ENOMEM; /* We'll just try again later. */ skb_copy_decrypted(buff, skb); mptcp_skb_ext_copy(buff, skb); sk_wmem_queued_add(sk, buff->truesize); sk_mem_charge(sk, buff->truesize); nlen = skb->len - len; buff->truesize += nlen; skb->truesize -= nlen; /* Correct the sequence numbers. */ TCP_SKB_CB(buff)->seq = TCP_SKB_CB(skb)->seq + len; TCP_SKB_CB(buff)->end_seq = TCP_SKB_CB(skb)->end_seq; TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(buff)->seq; /* PSH and FIN should only be set in the second packet. */ flags = TCP_SKB_CB(skb)->tcp_flags; TCP_SKB_CB(skb)->tcp_flags = flags & ~(TCPHDR_FIN | TCPHDR_PSH); TCP_SKB_CB(buff)->tcp_flags = flags; TCP_SKB_CB(buff)->sacked = TCP_SKB_CB(skb)->sacked; tcp_skb_fragment_eor(skb, buff); skb_split(skb, buff, len); skb_set_delivery_time(buff, skb->tstamp, true); tcp_fragment_tstamp(skb, buff); old_factor = tcp_skb_pcount(skb); /* Fix up tso_factor for both original and new SKB. */ tcp_set_skb_tso_segs(skb, mss_now); tcp_set_skb_tso_segs(buff, mss_now); /* Update delivered info for the new segment */ TCP_SKB_CB(buff)->tx = TCP_SKB_CB(skb)->tx; /* If this packet has been sent out already, we must * adjust the various packet counters. */ if (!before(tp->snd_nxt, TCP_SKB_CB(buff)->end_seq)) { int diff = old_factor - tcp_skb_pcount(skb) - tcp_skb_pcount(buff); if (diff) tcp_adjust_pcount(sk, skb, diff); } /* Link BUFF into the send queue. */ __skb_header_release(buff); tcp_insert_write_queue_after(skb, buff, sk, tcp_queue); if (tcp_queue == TCP_FRAG_IN_RTX_QUEUE) list_add(&buff->tcp_tsorted_anchor, &skb->tcp_tsorted_anchor); return 0; } /* This is similar to __pskb_pull_tail(). The difference is that pulled * data is not copied, but immediately discarded. */ static int __pskb_trim_head(struct sk_buff *skb, int len) { struct skb_shared_info *shinfo; int i, k, eat; DEBUG_NET_WARN_ON_ONCE(skb_headlen(skb)); eat = len; k = 0; shinfo = skb_shinfo(skb); for (i = 0; i < shinfo->nr_frags; i++) { int size = skb_frag_size(&shinfo->frags[i]); if (size <= eat) { skb_frag_unref(skb, i); eat -= size; } else { shinfo->frags[k] = shinfo->frags[i]; if (eat) { skb_frag_off_add(&shinfo->frags[k], eat); skb_frag_size_sub(&shinfo->frags[k], eat); eat = 0; } k++; } } shinfo->nr_frags = k; skb->data_len -= len; skb->len = skb->data_len; return len; } /* Remove acked data from a packet in the transmit queue. */ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len) { u32 delta_truesize; if (skb_unclone_keeptruesize(skb, GFP_ATOMIC)) return -ENOMEM; delta_truesize = __pskb_trim_head(skb, len); TCP_SKB_CB(skb)->seq += len; skb->truesize -= delta_truesize; sk_wmem_queued_add(sk, -delta_truesize); if (!skb_zcopy_pure(skb)) sk_mem_uncharge(sk, delta_truesize); /* Any change of skb->len requires recalculation of tso factor. */ if (tcp_skb_pcount(skb) > 1) tcp_set_skb_tso_segs(skb, tcp_skb_mss(skb)); return 0; } /* Calculate MSS not accounting any TCP options. */ static inline int __tcp_mtu_to_mss(struct sock *sk, int pmtu) { const struct tcp_sock *tp = tcp_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); int mss_now; /* Calculate base mss without TCP options: It is MMS_S - sizeof(tcphdr) of rfc1122 */ mss_now = pmtu - icsk->icsk_af_ops->net_header_len - sizeof(struct tcphdr); /* IPv6 adds a frag_hdr in case RTAX_FEATURE_ALLFRAG is set */ if (icsk->icsk_af_ops->net_frag_header_len) { const struct dst_entry *dst = __sk_dst_get(sk); if (dst && dst_allfrag(dst)) mss_now -= icsk->icsk_af_ops->net_frag_header_len; } /* Clamp it (mss_clamp does not include tcp options) */ if (mss_now > tp->rx_opt.mss_clamp) mss_now = tp->rx_opt.mss_clamp; /* Now subtract optional transport overhead */ mss_now -= icsk->icsk_ext_hdr_len; /* Then reserve room for full set of TCP options and 8 bytes of data */ mss_now = max(mss_now, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_min_snd_mss)); return mss_now; } /* Calculate MSS. Not accounting for SACKs here. */ int tcp_mtu_to_mss(struct sock *sk, int pmtu) { /* Subtract TCP options size, not including SACKs */ return __tcp_mtu_to_mss(sk, pmtu) - (tcp_sk(sk)->tcp_header_len - sizeof(struct tcphdr)); } EXPORT_SYMBOL(tcp_mtu_to_mss); /* Inverse of above */ int tcp_mss_to_mtu(struct sock *sk, int mss) { const struct tcp_sock *tp = tcp_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); int mtu; mtu = mss + tp->tcp_header_len + icsk->icsk_ext_hdr_len + icsk->icsk_af_ops->net_header_len; /* IPv6 adds a frag_hdr in case RTAX_FEATURE_ALLFRAG is set */ if (icsk->icsk_af_ops->net_frag_header_len) { const struct dst_entry *dst = __sk_dst_get(sk); if (dst && dst_allfrag(dst)) mtu += icsk->icsk_af_ops->net_frag_header_len; } return mtu; } EXPORT_SYMBOL(tcp_mss_to_mtu); /* MTU probing init per socket */ void tcp_mtup_init(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); struct net *net = sock_net(sk); icsk->icsk_mtup.enabled = READ_ONCE(net->ipv4.sysctl_tcp_mtu_probing) > 1; icsk->icsk_mtup.search_high = tp->rx_opt.mss_clamp + sizeof(struct tcphdr) + icsk->icsk_af_ops->net_header_len; icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, READ_ONCE(net->ipv4.sysctl_tcp_base_mss)); icsk->icsk_mtup.probe_size = 0; if (icsk->icsk_mtup.enabled) icsk->icsk_mtup.probe_timestamp = tcp_jiffies32; } EXPORT_SYMBOL(tcp_mtup_init); /* This function synchronize snd mss to current pmtu/exthdr set. tp->rx_opt.user_mss is mss set by user by TCP_MAXSEG. It does NOT counts for TCP options, but includes only bare TCP header. tp->rx_opt.mss_clamp is mss negotiated at connection setup. It is minimum of user_mss and mss received with SYN. It also does not include TCP options. inet_csk(sk)->icsk_pmtu_cookie is last pmtu, seen by this function. tp->mss_cache is current effective sending mss, including all tcp options except for SACKs. It is evaluated, taking into account current pmtu, but never exceeds tp->rx_opt.mss_clamp. NOTE1. rfc1122 clearly states that advertised MSS DOES NOT include either tcp or ip options. NOTE2. inet_csk(sk)->icsk_pmtu_cookie and tp->mss_cache are READ ONLY outside this function. --ANK (980731) */ unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu) { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); int mss_now; if (icsk->icsk_mtup.search_high > pmtu) icsk->icsk_mtup.search_high = pmtu; mss_now = tcp_mtu_to_mss(sk, pmtu); mss_now = tcp_bound_to_half_wnd(tp, mss_now); /* And store cached results */ icsk->icsk_pmtu_cookie = pmtu; if (icsk->icsk_mtup.enabled) mss_now = min(mss_now, tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low)); tp->mss_cache = mss_now; return mss_now; } EXPORT_SYMBOL(tcp_sync_mss); /* Compute the current effective MSS, taking SACKs and IP options, * and even PMTU discovery events into account. */ unsigned int tcp_current_mss(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); const struct dst_entry *dst = __sk_dst_get(sk); u32 mss_now; unsigned int header_len; struct tcp_out_options opts; struct tcp_md5sig_key *md5; mss_now = tp->mss_cache; if (dst) { u32 mtu = dst_mtu(dst); if (mtu != inet_csk(sk)->icsk_pmtu_cookie) mss_now = tcp_sync_mss(sk, mtu); } header_len = tcp_established_options(sk, NULL, &opts, &md5) + sizeof(struct tcphdr); /* The mss_cache is sized based on tp->tcp_header_len, which assumes * some common options. If this is an odd packet (because we have SACK * blocks etc) then our calculated header_len will be different, and * we have to adjust mss_now correspondingly */ if (header_len != tp->tcp_header_len) { int delta = (int) header_len - tp->tcp_header_len; mss_now -= delta; } return mss_now; } /* RFC2861, slow part. Adjust cwnd, after it was not full during one rto. * As additional protections, we do not touch cwnd in retransmission phases, * and if application hit its sndbuf limit recently. */ static void tcp_cwnd_application_limited(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); if (inet_csk(sk)->icsk_ca_state == TCP_CA_Open && sk->sk_socket && !test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { /* Limited by application or receiver window. */ u32 init_win = tcp_init_cwnd(tp, __sk_dst_get(sk)); u32 win_used = max(tp->snd_cwnd_used, init_win); if (win_used < tcp_snd_cwnd(tp)) { tp->snd_ssthresh = tcp_current_ssthresh(sk); tcp_snd_cwnd_set(tp, (tcp_snd_cwnd(tp) + win_used) >> 1); } tp->snd_cwnd_used = 0; } tp->snd_cwnd_stamp = tcp_jiffies32; } static void tcp_cwnd_validate(struct sock *sk, bool is_cwnd_limited) { const struct tcp_congestion_ops *ca_ops = inet_csk(sk)->icsk_ca_ops; struct tcp_sock *tp = tcp_sk(sk); /* Track the strongest available signal of the degree to which the cwnd * is fully utilized. If cwnd-limited then remember that fact for the * current window. If not cwnd-limited then track the maximum number of * outstanding packets in the current window. (If cwnd-limited then we * chose to not update tp->max_packets_out to avoid an extra else * clause with no functional impact.) */ if (!before(tp->snd_una, tp->cwnd_usage_seq) || is_cwnd_limited || (!tp->is_cwnd_limited && tp->packets_out > tp->max_packets_out)) { tp->is_cwnd_limited = is_cwnd_limited; tp->max_packets_out = tp->packets_out; tp->cwnd_usage_seq = tp->snd_nxt; } if (tcp_is_cwnd_limited(sk)) { /* Network is feed fully. */ tp->snd_cwnd_used = 0; tp->snd_cwnd_stamp = tcp_jiffies32; } else { /* Network starves. */ if (tp->packets_out > tp->snd_cwnd_used) tp->snd_cwnd_used = tp->packets_out; if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle) && (s32)(tcp_jiffies32 - tp->snd_cwnd_stamp) >= inet_csk(sk)->icsk_rto && !ca_ops->cong_control) tcp_cwnd_application_limited(sk); /* The following conditions together indicate the starvation * is caused by insufficient sender buffer: * 1) just sent some data (see tcp_write_xmit) * 2) not cwnd limited (this else condition) * 3) no more data to send (tcp_write_queue_empty()) * 4) application is hitting buffer limit (SOCK_NOSPACE) */ if (tcp_write_queue_empty(sk) && sk->sk_socket && test_bit(SOCK_NOSPACE, &sk->sk_socket->flags) && (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) tcp_chrono_start(sk, TCP_CHRONO_SNDBUF_LIMITED); } } /* Minshall's variant of the Nagle send check. */ static bool tcp_minshall_check(const struct tcp_sock *tp) { return after(tp->snd_sml, tp->snd_una) && !after(tp->snd_sml, tp->snd_nxt); } /* Update snd_sml if this skb is under mss * Note that a TSO packet might end with a sub-mss segment * The test is really : * if ((skb->len % mss) != 0) * tp->snd_sml = TCP_SKB_CB(skb)->end_seq; * But we can avoid doing the divide again given we already have * skb_pcount = skb->len / mss_now */ static void tcp_minshall_update(struct tcp_sock *tp, unsigned int mss_now, const struct sk_buff *skb) { if (skb->len < tcp_skb_pcount(skb) * mss_now) tp->snd_sml = TCP_SKB_CB(skb)->end_seq; } /* Return false, if packet can be sent now without violation Nagle's rules: * 1. It is full sized. (provided by caller in %partial bool) * 2. Or it contains FIN. (already checked by caller) * 3. Or TCP_CORK is not set, and TCP_NODELAY is set. * 4. Or TCP_CORK is not set, and all sent packets are ACKed. * With Minshall's modification: all sent small packets are ACKed. */ static bool tcp_nagle_check(bool partial, const struct tcp_sock *tp, int nonagle) { return partial && ((nonagle & TCP_NAGLE_CORK) || (!nonagle && tp->packets_out && tcp_minshall_check(tp))); } /* Return how many segs we'd like on a TSO packet, * depending on current pacing rate, and how close the peer is. * * Rationale is: * - For close peers, we rather send bigger packets to reduce * cpu costs, because occasional losses will be repaired fast. * - For long distance/rtt flows, we would like to get ACK clocking * with 1 ACK per ms. * * Use min_rtt to help adapt TSO burst size, with smaller min_rtt resulting * in bigger TSO bursts. We we cut the RTT-based allowance in half * for every 2^9 usec (aka 512 us) of RTT, so that the RTT-based allowance * is below 1500 bytes after 6 * ~500 usec = 3ms. */ static u32 tcp_tso_autosize(const struct sock *sk, unsigned int mss_now, int min_tso_segs) { unsigned long bytes; u32 r; bytes = sk->sk_pacing_rate >> READ_ONCE(sk->sk_pacing_shift); r = tcp_min_rtt(tcp_sk(sk)) >> READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_tso_rtt_log); if (r < BITS_PER_TYPE(sk->sk_gso_max_size)) bytes += sk->sk_gso_max_size >> r; bytes = min_t(unsigned long, bytes, sk->sk_gso_max_size); return max_t(u32, bytes / mss_now, min_tso_segs); } /* Return the number of segments we want in the skb we are transmitting. * See if congestion control module wants to decide; otherwise, autosize. */ static u32 tcp_tso_segs(struct sock *sk, unsigned int mss_now) { const struct tcp_congestion_ops *ca_ops = inet_csk(sk)->icsk_ca_ops; u32 min_tso, tso_segs; min_tso = ca_ops->min_tso_segs ? ca_ops->min_tso_segs(sk) : READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_min_tso_segs); tso_segs = tcp_tso_autosize(sk, mss_now, min_tso); return min_t(u32, tso_segs, sk->sk_gso_max_segs); } /* Returns the portion of skb which can be sent right away */ static unsigned int tcp_mss_split_point(const struct sock *sk, const struct sk_buff *skb, unsigned int mss_now, unsigned int max_segs, int nonagle) { const struct tcp_sock *tp = tcp_sk(sk); u32 partial, needed, window, max_len; window = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq; max_len = mss_now * max_segs; if (likely(max_len <= window && skb != tcp_write_queue_tail(sk))) return max_len; needed = min(skb->len, window); if (max_len <= needed) return max_len; partial = needed % mss_now; /* If last segment is not a full MSS, check if Nagle rules allow us * to include this last segment in this skb. * Otherwise, we'll split the skb at last MSS boundary */ if (tcp_nagle_check(partial != 0, tp, nonagle)) return needed - partial; return needed; } /* Can at least one segment of SKB be sent right now, according to the * congestion window rules? If so, return how many segments are allowed. */ static inline unsigned int tcp_cwnd_test(const struct tcp_sock *tp, const struct sk_buff *skb) { u32 in_flight, cwnd, halfcwnd; /* Don't be strict about the congestion window for the final FIN. */ if ((TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) && tcp_skb_pcount(skb) == 1) return 1; in_flight = tcp_packets_in_flight(tp); cwnd = tcp_snd_cwnd(tp); if (in_flight >= cwnd) return 0; /* For better scheduling, ensure we have at least * 2 GSO packets in flight. */ halfcwnd = max(cwnd >> 1, 1U); return min(halfcwnd, cwnd - in_flight); } /* Initialize TSO state of a skb. * This must be invoked the first time we consider transmitting * SKB onto the wire. */ static int tcp_init_tso_segs(struct sk_buff *skb, unsigned int mss_now) { int tso_segs = tcp_skb_pcount(skb); if (!tso_segs || (tso_segs > 1 && tcp_skb_mss(skb) != mss_now)) { tcp_set_skb_tso_segs(skb, mss_now); tso_segs = tcp_skb_pcount(skb); } return tso_segs; } /* Return true if the Nagle test allows this packet to be * sent now. */ static inline bool tcp_nagle_test(const struct tcp_sock *tp, const struct sk_buff *skb, unsigned int cur_mss, int nonagle) { /* Nagle rule does not apply to frames, which sit in the middle of the * write_queue (they have no chances to get new data). * * This is implemented in the callers, where they modify the 'nonagle' * argument based upon the location of SKB in the send queue. */ if (nonagle & TCP_NAGLE_PUSH) return true; /* Don't use the nagle rule for urgent data (or for the final FIN). */ if (tcp_urg_mode(tp) || (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) return true; if (!tcp_nagle_check(skb->len < cur_mss, tp, nonagle)) return true; return false; } /* Does at least the first segment of SKB fit into the send window? */ static bool tcp_snd_wnd_test(const struct tcp_sock *tp, const struct sk_buff *skb, unsigned int cur_mss) { u32 end_seq = TCP_SKB_CB(skb)->end_seq; if (skb->len > cur_mss) end_seq = TCP_SKB_CB(skb)->seq + cur_mss; return !after(end_seq, tcp_wnd_end(tp)); } /* Trim TSO SKB to LEN bytes, put the remaining data into a new packet * which is put after SKB on the list. It is very much like * tcp_fragment() except that it may make several kinds of assumptions * in order to speed up the splitting operation. In particular, we * know that all the data is in scatter-gather pages, and that the * packet has never been sent out before (and thus is not cloned). */ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len, unsigned int mss_now, gfp_t gfp) { int nlen = skb->len - len; struct sk_buff *buff; u8 flags; /* All of a TSO frame must be composed of paged data. */ DEBUG_NET_WARN_ON_ONCE(skb->len != skb->data_len); buff = tcp_stream_alloc_skb(sk, gfp, true); if (unlikely(!buff)) return -ENOMEM; skb_copy_decrypted(buff, skb); mptcp_skb_ext_copy(buff, skb); sk_wmem_queued_add(sk, buff->truesize); sk_mem_charge(sk, buff->truesize); buff->truesize += nlen; skb->truesize -= nlen; /* Correct the sequence numbers. */ TCP_SKB_CB(buff)->seq = TCP_SKB_CB(skb)->seq + len; TCP_SKB_CB(buff)->end_seq = TCP_SKB_CB(skb)->end_seq; TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(buff)->seq; /* PSH and FIN should only be set in the second packet. */ flags = TCP_SKB_CB(skb)->tcp_flags; TCP_SKB_CB(skb)->tcp_flags = flags & ~(TCPHDR_FIN | TCPHDR_PSH); TCP_SKB_CB(buff)->tcp_flags = flags; tcp_skb_fragment_eor(skb, buff); skb_split(skb, buff, len); tcp_fragment_tstamp(skb, buff); /* Fix up tso_factor for both original and new SKB. */ tcp_set_skb_tso_segs(skb, mss_now); tcp_set_skb_tso_segs(buff, mss_now); /* Link BUFF into the send queue. */ __skb_header_release(buff); tcp_insert_write_queue_after(skb, buff, sk, TCP_FRAG_IN_WRITE_QUEUE); return 0; } /* Try to defer sending, if possible, in order to minimize the amount * of TSO splitting we do. View it as a kind of TSO Nagle test. * * This algorithm is from John Heffner. */ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb, bool *is_cwnd_limited, bool *is_rwnd_limited, u32 max_segs) { const struct inet_connection_sock *icsk = inet_csk(sk); u32 send_win, cong_win, limit, in_flight; struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *head; int win_divisor; s64 delta; if (icsk->icsk_ca_state >= TCP_CA_Recovery) goto send_now; /* Avoid bursty behavior by allowing defer * only if the last write was recent (1 ms). * Note that tp->tcp_wstamp_ns can be in the future if we have * packets waiting in a qdisc or device for EDT delivery. */ delta = tp->tcp_clock_cache - tp->tcp_wstamp_ns - NSEC_PER_MSEC; if (delta > 0) goto send_now; in_flight = tcp_packets_in_flight(tp); BUG_ON(tcp_skb_pcount(skb) <= 1); BUG_ON(tcp_snd_cwnd(tp) <= in_flight); send_win = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq; /* From in_flight test above, we know that cwnd > in_flight. */ cong_win = (tcp_snd_cwnd(tp) - in_flight) * tp->mss_cache; limit = min(send_win, cong_win); /* If a full-sized TSO skb can be sent, do it. */ if (limit >= max_segs * tp->mss_cache) goto send_now; /* Middle in queue won't get any more data, full sendable already? */ if ((skb != tcp_write_queue_tail(sk)) && (limit >= skb->len)) goto send_now; win_divisor = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_tso_win_divisor); if (win_divisor) { u32 chunk = min(tp->snd_wnd, tcp_snd_cwnd(tp) * tp->mss_cache); /* If at least some fraction of a window is available, * just use it. */ chunk /= win_divisor; if (limit >= chunk) goto send_now; } else { /* Different approach, try not to defer past a single * ACK. Receiver should ACK every other full sized * frame, so if we have space for more than 3 frames * then send now. */ if (limit > tcp_max_tso_deferred_mss(tp) * tp->mss_cache) goto send_now; } /* TODO : use tsorted_sent_queue ? */ head = tcp_rtx_queue_head(sk); if (!head) goto send_now; delta = tp->tcp_clock_cache - head->tstamp; /* If next ACK is likely to come too late (half srtt), do not defer */ if ((s64)(delta - (u64)NSEC_PER_USEC * (tp->srtt_us >> 4)) < 0) goto send_now; /* Ok, it looks like it is advisable to defer. * Three cases are tracked : * 1) We are cwnd-limited * 2) We are rwnd-limited * 3) We are application limited. */ if (cong_win < send_win) { if (cong_win <= skb->len) { *is_cwnd_limited = true; return true; } } else { if (send_win <= skb->len) { *is_rwnd_limited = true; return true; } } /* If this packet won't get more data, do not wait. */ if ((TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) || TCP_SKB_CB(skb)->eor) goto send_now; return true; send_now: return false; } static inline void tcp_mtu_check_reprobe(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); u32 interval; s32 delta; interval = READ_ONCE(net->ipv4.sysctl_tcp_probe_interval); delta = tcp_jiffies32 - icsk->icsk_mtup.probe_timestamp; if (unlikely(delta >= interval * HZ)) { int mss = tcp_current_mss(sk); /* Update current search range */ icsk->icsk_mtup.probe_size = 0; icsk->icsk_mtup.search_high = tp->rx_opt.mss_clamp + sizeof(struct tcphdr) + icsk->icsk_af_ops->net_header_len; icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, mss); /* Update probe time stamp */ icsk->icsk_mtup.probe_timestamp = tcp_jiffies32; } } static bool tcp_can_coalesce_send_queue_head(struct sock *sk, int len) { struct sk_buff *skb, *next; skb = tcp_send_head(sk); tcp_for_write_queue_from_safe(skb, next, sk) { if (len <= skb->len) break; if (unlikely(TCP_SKB_CB(skb)->eor) || tcp_has_tx_tstamp(skb) || !skb_pure_zcopy_same(skb, next)) return false; len -= skb->len; } return true; } static int tcp_clone_payload(struct sock *sk, struct sk_buff *to, int probe_size) { skb_frag_t *lastfrag = NULL, *fragto = skb_shinfo(to)->frags; int i, todo, len = 0, nr_frags = 0; const struct sk_buff *skb; if (!sk_wmem_schedule(sk, to->truesize + probe_size)) return -ENOMEM; skb_queue_walk(&sk->sk_write_queue, skb) { const skb_frag_t *fragfrom = skb_shinfo(skb)->frags; if (skb_headlen(skb)) return -EINVAL; for (i = 0; i < skb_shinfo(skb)->nr_frags; i++, fragfrom++) { if (len >= probe_size) goto commit; todo = min_t(int, skb_frag_size(fragfrom), probe_size - len); len += todo; if (lastfrag && skb_frag_page(fragfrom) == skb_frag_page(lastfrag) && skb_frag_off(fragfrom) == skb_frag_off(lastfrag) + skb_frag_size(lastfrag)) { skb_frag_size_add(lastfrag, todo); continue; } if (unlikely(nr_frags == MAX_SKB_FRAGS)) return -E2BIG; skb_frag_page_copy(fragto, fragfrom); skb_frag_off_copy(fragto, fragfrom); skb_frag_size_set(fragto, todo); nr_frags++; lastfrag = fragto++; } } commit: WARN_ON_ONCE(len != probe_size); for (i = 0; i < nr_frags; i++) skb_frag_ref(to, i); skb_shinfo(to)->nr_frags = nr_frags; to->truesize += probe_size; to->len += probe_size; to->data_len += probe_size; __skb_header_release(to); return 0; } /* Create a new MTU probe if we are ready. * MTU probe is regularly attempting to increase the path MTU by * deliberately sending larger packets. This discovers routing * changes resulting in larger path MTUs. * * Returns 0 if we should wait to probe (no cwnd available), * 1 if a probe was sent, * -1 otherwise */ static int tcp_mtu_probe(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb, *nskb, *next; struct net *net = sock_net(sk); int probe_size; int size_needed; int copy, len; int mss_now; int interval; /* Not currently probing/verifying, * not in recovery, * have enough cwnd, and * not SACKing (the variable headers throw things off) */ if (likely(!icsk->icsk_mtup.enabled || icsk->icsk_mtup.probe_size || inet_csk(sk)->icsk_ca_state != TCP_CA_Open || tcp_snd_cwnd(tp) < 11 || tp->rx_opt.num_sacks || tp->rx_opt.dsack)) return -1; /* Use binary search for probe_size between tcp_mss_base, * and current mss_clamp. if (search_high - search_low) * smaller than a threshold, backoff from probing. */ mss_now = tcp_current_mss(sk); probe_size = tcp_mtu_to_mss(sk, (icsk->icsk_mtup.search_high + icsk->icsk_mtup.search_low) >> 1); size_needed = probe_size + (tp->reordering + 1) * tp->mss_cache; interval = icsk->icsk_mtup.search_high - icsk->icsk_mtup.search_low; /* When misfortune happens, we are reprobing actively, * and then reprobe timer has expired. We stick with current * probing process by not resetting search range to its orignal. */ if (probe_size > tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_high) || interval < READ_ONCE(net->ipv4.sysctl_tcp_probe_threshold)) { /* Check whether enough time has elaplased for * another round of probing. */ tcp_mtu_check_reprobe(sk); return -1; } /* Have enough data in the send queue to probe? */ if (tp->write_seq - tp->snd_nxt < size_needed) return -1; if (tp->snd_wnd < size_needed) return -1; if (after(tp->snd_nxt + size_needed, tcp_wnd_end(tp))) return 0; /* Do we need to wait to drain cwnd? With none in flight, don't stall */ if (tcp_packets_in_flight(tp) + 2 > tcp_snd_cwnd(tp)) { if (!tcp_packets_in_flight(tp)) return -1; else return 0; } if (!tcp_can_coalesce_send_queue_head(sk, probe_size)) return -1; /* We're allowed to probe. Build it now. */ nskb = tcp_stream_alloc_skb(sk, GFP_ATOMIC, false); if (!nskb) return -1; /* build the payload, and be prepared to abort if this fails. */ if (tcp_clone_payload(sk, nskb, probe_size)) { consume_skb(nskb); return -1; } sk_wmem_queued_add(sk, nskb->truesize); sk_mem_charge(sk, nskb->truesize); skb = tcp_send_head(sk); skb_copy_decrypted(nskb, skb); mptcp_skb_ext_copy(nskb, skb); TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(skb)->seq; TCP_SKB_CB(nskb)->end_seq = TCP_SKB_CB(skb)->seq + probe_size; TCP_SKB_CB(nskb)->tcp_flags = TCPHDR_ACK; tcp_insert_write_queue_before(nskb, skb, sk); tcp_highest_sack_replace(sk, skb, nskb); len = 0; tcp_for_write_queue_from_safe(skb, next, sk) { copy = min_t(int, skb->len, probe_size - len); if (skb->len <= copy) { /* We've eaten all the data from this skb. * Throw it away. */ TCP_SKB_CB(nskb)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags; /* If this is the last SKB we copy and eor is set * we need to propagate it to the new skb. */ TCP_SKB_CB(nskb)->eor = TCP_SKB_CB(skb)->eor; tcp_skb_collapse_tstamp(nskb, skb); tcp_unlink_write_queue(skb, sk); tcp_wmem_free_skb(sk, skb); } else { TCP_SKB_CB(nskb)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags & ~(TCPHDR_FIN|TCPHDR_PSH); __pskb_trim_head(skb, copy); tcp_set_skb_tso_segs(skb, mss_now); TCP_SKB_CB(skb)->seq += copy; } len += copy; if (len >= probe_size) break; } tcp_init_tso_segs(nskb, nskb->len); /* We're ready to send. If this fails, the probe will * be resegmented into mss-sized pieces by tcp_write_xmit(). */ if (!tcp_transmit_skb(sk, nskb, 1, GFP_ATOMIC)) { /* Decrement cwnd here because we are sending * effectively two packets. */ tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) - 1); tcp_event_new_data_sent(sk, nskb); icsk->icsk_mtup.probe_size = tcp_mss_to_mtu(sk, nskb->len); tp->mtu_probe.probe_seq_start = TCP_SKB_CB(nskb)->seq; tp->mtu_probe.probe_seq_end = TCP_SKB_CB(nskb)->end_seq; return 1; } return -1; } static bool tcp_pacing_check(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); if (!tcp_needs_internal_pacing(sk)) return false; if (tp->tcp_wstamp_ns <= tp->tcp_clock_cache) return false; if (!hrtimer_is_queued(&tp->pacing_timer)) { hrtimer_start(&tp->pacing_timer, ns_to_ktime(tp->tcp_wstamp_ns), HRTIMER_MODE_ABS_PINNED_SOFT); sock_hold(sk); } return true; } /* TCP Small Queues : * Control number of packets in qdisc/devices to two packets / or ~1 ms. * (These limits are doubled for retransmits) * This allows for : * - better RTT estimation and ACK scheduling * - faster recovery * - high rates * Alas, some drivers / subsystems require a fair amount * of queued bytes to ensure line rate. * One example is wifi aggregation (802.11 AMPDU) */ static bool tcp_small_queue_check(struct sock *sk, const struct sk_buff *skb, unsigned int factor) { unsigned long limit; limit = max_t(unsigned long, 2 * skb->truesize, sk->sk_pacing_rate >> READ_ONCE(sk->sk_pacing_shift)); if (sk->sk_pacing_status == SK_PACING_NONE) limit = min_t(unsigned long, limit, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_limit_output_bytes)); limit <<= factor; if (static_branch_unlikely(&tcp_tx_delay_enabled) && tcp_sk(sk)->tcp_tx_delay) { u64 extra_bytes = (u64)sk->sk_pacing_rate * tcp_sk(sk)->tcp_tx_delay; /* TSQ is based on skb truesize sum (sk_wmem_alloc), so we * approximate our needs assuming an ~100% skb->truesize overhead. * USEC_PER_SEC is approximated by 2^20. * do_div(extra_bytes, USEC_PER_SEC/2) is replaced by a right shift. */ extra_bytes >>= (20 - 1); limit += extra_bytes; } if (refcount_read(&sk->sk_wmem_alloc) > limit) { /* Always send skb if rtx queue is empty. * No need to wait for TX completion to call us back, * after softirq/tasklet schedule. * This helps when TX completions are delayed too much. */ if (tcp_rtx_queue_empty(sk)) return false; set_bit(TSQ_THROTTLED, &sk->sk_tsq_flags); /* It is possible TX completion already happened * before we set TSQ_THROTTLED, so we must * test again the condition. */ smp_mb__after_atomic(); if (refcount_read(&sk->sk_wmem_alloc) > limit) return true; } return false; } static void tcp_chrono_set(struct tcp_sock *tp, const enum tcp_chrono new) { const u32 now = tcp_jiffies32; enum tcp_chrono old = tp->chrono_type; if (old > TCP_CHRONO_UNSPEC) tp->chrono_stat[old - 1] += now - tp->chrono_start; tp->chrono_start = now; tp->chrono_type = new; } void tcp_chrono_start(struct sock *sk, const enum tcp_chrono type) { struct tcp_sock *tp = tcp_sk(sk); /* If there are multiple conditions worthy of tracking in a * chronograph then the highest priority enum takes precedence * over the other conditions. So that if something "more interesting" * starts happening, stop the previous chrono and start a new one. */ if (type > tp->chrono_type) tcp_chrono_set(tp, type); } void tcp_chrono_stop(struct sock *sk, const enum tcp_chrono type) { struct tcp_sock *tp = tcp_sk(sk); /* There are multiple conditions worthy of tracking in a * chronograph, so that the highest priority enum takes * precedence over the other conditions (see tcp_chrono_start). * If a condition stops, we only stop chrono tracking if * it's the "most interesting" or current chrono we are * tracking and starts busy chrono if we have pending data. */ if (tcp_rtx_and_write_queues_empty(sk)) tcp_chrono_set(tp, TCP_CHRONO_UNSPEC); else if (type == tp->chrono_type) tcp_chrono_set(tp, TCP_CHRONO_BUSY); } /* This routine writes packets to the network. It advances the * send_head. This happens as incoming acks open up the remote * window for us. * * LARGESEND note: !tcp_urg_mode is overkill, only frames between * snd_up-64k-mss .. snd_up cannot be large. However, taking into * account rare use of URG, this is not a big flaw. * * Send at most one packet when push_one > 0. Temporarily ignore * cwnd limit to force at most one packet out when push_one == 2. * Returns true, if no segments are in flight and we have queued segments, * but cannot send anything now because of SWS or another problem. */ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, int push_one, gfp_t gfp) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; unsigned int tso_segs, sent_pkts; int cwnd_quota; int result; bool is_cwnd_limited = false, is_rwnd_limited = false; u32 max_segs; sent_pkts = 0; tcp_mstamp_refresh(tp); if (!push_one) { /* Do MTU probing. */ result = tcp_mtu_probe(sk); if (!result) { return false; } else if (result > 0) { sent_pkts = 1; } } max_segs = tcp_tso_segs(sk, mss_now); while ((skb = tcp_send_head(sk))) { unsigned int limit; if (unlikely(tp->repair) && tp->repair_queue == TCP_SEND_QUEUE) { /* "skb_mstamp_ns" is used as a start point for the retransmit timer */ tp->tcp_wstamp_ns = tp->tcp_clock_cache; skb_set_delivery_time(skb, tp->tcp_wstamp_ns, true); list_move_tail(&skb->tcp_tsorted_anchor, &tp->tsorted_sent_queue); tcp_init_tso_segs(skb, mss_now); goto repair; /* Skip network transmission */ } if (tcp_pacing_check(sk)) break; tso_segs = tcp_init_tso_segs(skb, mss_now); BUG_ON(!tso_segs); cwnd_quota = tcp_cwnd_test(tp, skb); if (!cwnd_quota) { if (push_one == 2) /* Force out a loss probe pkt. */ cwnd_quota = 1; else break; } if (unlikely(!tcp_snd_wnd_test(tp, skb, mss_now))) { is_rwnd_limited = true; break; } if (tso_segs == 1) { if (unlikely(!tcp_nagle_test(tp, skb, mss_now, (tcp_skb_is_last(sk, skb) ? nonagle : TCP_NAGLE_PUSH)))) break; } else { if (!push_one && tcp_tso_should_defer(sk, skb, &is_cwnd_limited, &is_rwnd_limited, max_segs)) break; } limit = mss_now; if (tso_segs > 1 && !tcp_urg_mode(tp)) limit = tcp_mss_split_point(sk, skb, mss_now, min_t(unsigned int, cwnd_quota, max_segs), nonagle); if (skb->len > limit && unlikely(tso_fragment(sk, skb, limit, mss_now, gfp))) break; if (tcp_small_queue_check(sk, skb, 0)) break; /* Argh, we hit an empty skb(), presumably a thread * is sleeping in sendmsg()/sk_stream_wait_memory(). * We do not want to send a pure-ack packet and have * a strange looking rtx queue with empty packet(s). */ if (TCP_SKB_CB(skb)->end_seq == TCP_SKB_CB(skb)->seq) break; if (unlikely(tcp_transmit_skb(sk, skb, 1, gfp))) break; repair: /* Advance the send_head. This one is sent out. * This call will increment packets_out. */ tcp_event_new_data_sent(sk, skb); tcp_minshall_update(tp, mss_now, skb); sent_pkts += tcp_skb_pcount(skb); if (push_one) break; } if (is_rwnd_limited) tcp_chrono_start(sk, TCP_CHRONO_RWND_LIMITED); else tcp_chrono_stop(sk, TCP_CHRONO_RWND_LIMITED); is_cwnd_limited |= (tcp_packets_in_flight(tp) >= tcp_snd_cwnd(tp)); if (likely(sent_pkts || is_cwnd_limited)) tcp_cwnd_validate(sk, is_cwnd_limited); if (likely(sent_pkts)) { if (tcp_in_cwnd_reduction(sk)) tp->prr_out += sent_pkts; /* Send one loss probe per tail loss episode. */ if (push_one != 2) tcp_schedule_loss_probe(sk, false); return false; } return !tp->packets_out && !tcp_write_queue_empty(sk); } bool tcp_schedule_loss_probe(struct sock *sk, bool advancing_rto) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); u32 timeout, rto_delta_us; int early_retrans; /* Don't do any loss probe on a Fast Open connection before 3WHS * finishes. */ if (rcu_access_pointer(tp->fastopen_rsk)) return false; early_retrans = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_early_retrans); /* Schedule a loss probe in 2*RTT for SACK capable connections * not in loss recovery, that are either limited by cwnd or application. */ if ((early_retrans != 3 && early_retrans != 4) || !tp->packets_out || !tcp_is_sack(tp) || (icsk->icsk_ca_state != TCP_CA_Open && icsk->icsk_ca_state != TCP_CA_CWR)) return false; /* Probe timeout is 2*rtt. Add minimum RTO to account * for delayed ack when there's one outstanding packet. If no RTT * sample is available then probe after TCP_TIMEOUT_INIT. */ if (tp->srtt_us) { timeout = usecs_to_jiffies(tp->srtt_us >> 2); if (tp->packets_out == 1) timeout += TCP_RTO_MIN; else timeout += TCP_TIMEOUT_MIN; } else { timeout = TCP_TIMEOUT_INIT; } /* If the RTO formula yields an earlier time, then use that time. */ rto_delta_us = advancing_rto ? jiffies_to_usecs(inet_csk(sk)->icsk_rto) : tcp_rto_delta_us(sk); /* How far in future is RTO? */ if (rto_delta_us > 0) timeout = min_t(u32, timeout, usecs_to_jiffies(rto_delta_us)); tcp_reset_xmit_timer(sk, ICSK_TIME_LOSS_PROBE, timeout, TCP_RTO_MAX); return true; } /* Thanks to skb fast clones, we can detect if a prior transmit of * a packet is still in a qdisc or driver queue. * In this case, there is very little point doing a retransmit ! */ static bool skb_still_in_host_queue(struct sock *sk, const struct sk_buff *skb) { if (unlikely(skb_fclone_busy(sk, skb))) { set_bit(TSQ_THROTTLED, &sk->sk_tsq_flags); smp_mb__after_atomic(); if (skb_fclone_busy(sk, skb)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSPURIOUS_RTX_HOSTQUEUES); return true; } } return false; } /* When probe timeout (PTO) fires, try send a new segment if possible, else * retransmit the last segment. */ void tcp_send_loss_probe(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; int pcount; int mss = tcp_current_mss(sk); /* At most one outstanding TLP */ if (tp->tlp_high_seq) goto rearm_timer; tp->tlp_retrans = 0; skb = tcp_send_head(sk); if (skb && tcp_snd_wnd_test(tp, skb, mss)) { pcount = tp->packets_out; tcp_write_xmit(sk, mss, TCP_NAGLE_OFF, 2, GFP_ATOMIC); if (tp->packets_out > pcount) goto probe_sent; goto rearm_timer; } skb = skb_rb_last(&sk->tcp_rtx_queue); if (unlikely(!skb)) { WARN_ONCE(tp->packets_out, "invalid inflight: %u state %u cwnd %u mss %d\n", tp->packets_out, sk->sk_state, tcp_snd_cwnd(tp), mss); inet_csk(sk)->icsk_pending = 0; return; } if (skb_still_in_host_queue(sk, skb)) goto rearm_timer; pcount = tcp_skb_pcount(skb); if (WARN_ON(!pcount)) goto rearm_timer; if ((pcount > 1) && (skb->len > (pcount - 1) * mss)) { if (unlikely(tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb, (pcount - 1) * mss, mss, GFP_ATOMIC))) goto rearm_timer; skb = skb_rb_next(skb); } if (WARN_ON(!skb || !tcp_skb_pcount(skb))) goto rearm_timer; if (__tcp_retransmit_skb(sk, skb, 1)) goto rearm_timer; tp->tlp_retrans = 1; probe_sent: /* Record snd_nxt for loss detection. */ tp->tlp_high_seq = tp->snd_nxt; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPLOSSPROBES); /* Reset s.t. tcp_rearm_rto will restart timer from now */ inet_csk(sk)->icsk_pending = 0; rearm_timer: tcp_rearm_rto(sk); } /* Push out any pending frames which were held back due to * TCP_CORK or attempt at coalescing tiny packets. * The socket must be locked by the caller. */ void __tcp_push_pending_frames(struct sock *sk, unsigned int cur_mss, int nonagle) { /* If we are closed, the bytes will have to remain here. * In time closedown will finish, we empty the write queue and * all will be happy. */ if (unlikely(sk->sk_state == TCP_CLOSE)) return; if (tcp_write_xmit(sk, cur_mss, nonagle, 0, sk_gfp_mask(sk, GFP_ATOMIC))) tcp_check_probe_timer(sk); } /* Send _single_ skb sitting at the send head. This function requires * true push pending frames to setup probe timer etc. */ void tcp_push_one(struct sock *sk, unsigned int mss_now) { struct sk_buff *skb = tcp_send_head(sk); BUG_ON(!skb || skb->len < mss_now); tcp_write_xmit(sk, mss_now, TCP_NAGLE_PUSH, 1, sk->sk_allocation); } /* This function returns the amount that we can raise the * usable window based on the following constraints * * 1. The window can never be shrunk once it is offered (RFC 793) * 2. We limit memory per socket * * RFC 1122: * "the suggested [SWS] avoidance algorithm for the receiver is to keep * RECV.NEXT + RCV.WIN fixed until: * RCV.BUFF - RCV.USER - RCV.WINDOW >= min(1/2 RCV.BUFF, MSS)" * * i.e. don't raise the right edge of the window until you can raise * it at least MSS bytes. * * Unfortunately, the recommended algorithm breaks header prediction, * since header prediction assumes th->window stays fixed. * * Strictly speaking, keeping th->window fixed violates the receiver * side SWS prevention criteria. The problem is that under this rule * a stream of single byte packets will cause the right side of the * window to always advance by a single byte. * * Of course, if the sender implements sender side SWS prevention * then this will not be a problem. * * BSD seems to make the following compromise: * * If the free space is less than the 1/4 of the maximum * space available and the free space is less than 1/2 mss, * then set the window to 0. * [ Actually, bsd uses MSS and 1/4 of maximal _window_ ] * Otherwise, just prevent the window from shrinking * and from being larger than the largest representable value. * * This prevents incremental opening of the window in the regime * where TCP is limited by the speed of the reader side taking * data out of the TCP receive queue. It does nothing about * those cases where the window is constrained on the sender side * because the pipeline is full. * * BSD also seems to "accidentally" limit itself to windows that are a * multiple of MSS, at least until the free space gets quite small. * This would appear to be a side effect of the mbuf implementation. * Combining these two algorithms results in the observed behavior * of having a fixed window size at almost all times. * * Below we obtain similar behavior by forcing the offered window to * a multiple of the mss when it is feasible to do so. * * Note, we don't "adjust" for TIMESTAMP or SACK option bytes. * Regular options like TIMESTAMP are taken into account. */ u32 __tcp_select_window(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); /* MSS for the peer's data. Previous versions used mss_clamp * here. I don't know if the value based on our guesses * of peer's MSS is better for the performance. It's more correct * but may be worse for the performance because of rcv_mss * fluctuations. --SAW 1998/11/1 */ int mss = icsk->icsk_ack.rcv_mss; int free_space = tcp_space(sk); int allowed_space = tcp_full_space(sk); int full_space, window; if (sk_is_mptcp(sk)) mptcp_space(sk, &free_space, &allowed_space); full_space = min_t(int, tp->window_clamp, allowed_space); if (unlikely(mss > full_space)) { mss = full_space; if (mss <= 0) return 0; } /* Only allow window shrink if the sysctl is enabled and we have * a non-zero scaling factor in effect. */ if (READ_ONCE(net->ipv4.sysctl_tcp_shrink_window) && tp->rx_opt.rcv_wscale) goto shrink_window_allowed; /* do not allow window to shrink */ if (free_space < (full_space >> 1)) { icsk->icsk_ack.quick = 0; if (tcp_under_memory_pressure(sk)) tcp_adjust_rcv_ssthresh(sk); /* free_space might become our new window, make sure we don't * increase it due to wscale. */ free_space = round_down(free_space, 1 << tp->rx_opt.rcv_wscale); /* if free space is less than mss estimate, or is below 1/16th * of the maximum allowed, try to move to zero-window, else * tcp_clamp_window() will grow rcv buf up to tcp_rmem[2], and * new incoming data is dropped due to memory limits. * With large window, mss test triggers way too late in order * to announce zero window in time before rmem limit kicks in. */ if (free_space < (allowed_space >> 4) || free_space < mss) return 0; } if (free_space > tp->rcv_ssthresh) free_space = tp->rcv_ssthresh; /* Don't do rounding if we are using window scaling, since the * scaled window will not line up with the MSS boundary anyway. */ if (tp->rx_opt.rcv_wscale) { window = free_space; /* Advertise enough space so that it won't get scaled away. * Import case: prevent zero window announcement if * 1<<rcv_wscale > mss. */ window = ALIGN(window, (1 << tp->rx_opt.rcv_wscale)); } else { window = tp->rcv_wnd; /* Get the largest window that is a nice multiple of mss. * Window clamp already applied above. * If our current window offering is within 1 mss of the * free space we just keep it. This prevents the divide * and multiply from happening most of the time. * We also don't do any window rounding when the free space * is too small. */ if (window <= free_space - mss || window > free_space) window = rounddown(free_space, mss); else if (mss == full_space && free_space > window + (full_space >> 1)) window = free_space; } return window; shrink_window_allowed: /* new window should always be an exact multiple of scaling factor */ free_space = round_down(free_space, 1 << tp->rx_opt.rcv_wscale); if (free_space < (full_space >> 1)) { icsk->icsk_ack.quick = 0; if (tcp_under_memory_pressure(sk)) tcp_adjust_rcv_ssthresh(sk); /* if free space is too low, return a zero window */ if (free_space < (allowed_space >> 4) || free_space < mss || free_space < (1 << tp->rx_opt.rcv_wscale)) return 0; } if (free_space > tp->rcv_ssthresh) { free_space = tp->rcv_ssthresh; /* new window should always be an exact multiple of scaling factor * * For this case, we ALIGN "up" (increase free_space) because * we know free_space is not zero here, it has been reduced from * the memory-based limit, and rcv_ssthresh is not a hard limit * (unlike sk_rcvbuf). */ free_space = ALIGN(free_space, (1 << tp->rx_opt.rcv_wscale)); } return free_space; } void tcp_skb_collapse_tstamp(struct sk_buff *skb, const struct sk_buff *next_skb) { if (unlikely(tcp_has_tx_tstamp(next_skb))) { const struct skb_shared_info *next_shinfo = skb_shinfo(next_skb); struct skb_shared_info *shinfo = skb_shinfo(skb); shinfo->tx_flags |= next_shinfo->tx_flags & SKBTX_ANY_TSTAMP; shinfo->tskey = next_shinfo->tskey; TCP_SKB_CB(skb)->txstamp_ack |= TCP_SKB_CB(next_skb)->txstamp_ack; } } /* Collapses two adjacent SKB's during retransmission. */ static bool tcp_collapse_retrans(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *next_skb = skb_rb_next(skb); int next_skb_size; next_skb_size = next_skb->len; BUG_ON(tcp_skb_pcount(skb) != 1 || tcp_skb_pcount(next_skb) != 1); if (next_skb_size && !tcp_skb_shift(skb, next_skb, 1, next_skb_size)) return false; tcp_highest_sack_replace(sk, next_skb, skb); /* Update sequence range on original skb. */ TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(next_skb)->end_seq; /* Merge over control information. This moves PSH/FIN etc. over */ TCP_SKB_CB(skb)->tcp_flags |= TCP_SKB_CB(next_skb)->tcp_flags; /* All done, get rid of second SKB and account for it so * packet counting does not break. */ TCP_SKB_CB(skb)->sacked |= TCP_SKB_CB(next_skb)->sacked & TCPCB_EVER_RETRANS; TCP_SKB_CB(skb)->eor = TCP_SKB_CB(next_skb)->eor; /* changed transmit queue under us so clear hints */ tcp_clear_retrans_hints_partial(tp); if (next_skb == tp->retransmit_skb_hint) tp->retransmit_skb_hint = skb; tcp_adjust_pcount(sk, next_skb, tcp_skb_pcount(next_skb)); tcp_skb_collapse_tstamp(skb, next_skb); tcp_rtx_queue_unlink_and_free(next_skb, sk); return true; } /* Check if coalescing SKBs is legal. */ static bool tcp_can_collapse(const struct sock *sk, const struct sk_buff *skb) { if (tcp_skb_pcount(skb) > 1) return false; if (skb_cloned(skb)) return false; /* Some heuristics for collapsing over SACK'd could be invented */ if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) return false; return true; } /* Collapse packets in the retransmit queue to make to create * less packets on the wire. This is only done on retransmission. */ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *to, int space) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb = to, *tmp; bool first = true; if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_retrans_collapse)) return; if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN) return; skb_rbtree_walk_from_safe(skb, tmp) { if (!tcp_can_collapse(sk, skb)) break; if (!tcp_skb_can_collapse(to, skb)) break; space -= skb->len; if (first) { first = false; continue; } if (space < 0) break; if (after(TCP_SKB_CB(skb)->end_seq, tcp_wnd_end(tp))) break; if (!tcp_collapse_retrans(sk, to)) break; } } /* This retransmits one SKB. Policy decisions and retransmit queue * state updates are done by the caller. Returns non-zero if an * error occurred which prevented the send. */ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); unsigned int cur_mss; int diff, len, err; int avail_wnd; /* Inconclusive MTU probe */ if (icsk->icsk_mtup.probe_size) icsk->icsk_mtup.probe_size = 0; if (skb_still_in_host_queue(sk, skb)) return -EBUSY; if (before(TCP_SKB_CB(skb)->seq, tp->snd_una)) { if (unlikely(before(TCP_SKB_CB(skb)->end_seq, tp->snd_una))) { WARN_ON_ONCE(1); return -EINVAL; } if (tcp_trim_head(sk, skb, tp->snd_una - TCP_SKB_CB(skb)->seq)) return -ENOMEM; } if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk)) return -EHOSTUNREACH; /* Routing failure or similar. */ cur_mss = tcp_current_mss(sk); avail_wnd = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq; /* If receiver has shrunk his window, and skb is out of * new window, do not retransmit it. The exception is the * case, when window is shrunk to zero. In this case * our retransmit of one segment serves as a zero window probe. */ if (avail_wnd <= 0) { if (TCP_SKB_CB(skb)->seq != tp->snd_una) return -EAGAIN; avail_wnd = cur_mss; } len = cur_mss * segs; if (len > avail_wnd) { len = rounddown(avail_wnd, cur_mss); if (!len) len = avail_wnd; } if (skb->len > len) { if (tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb, len, cur_mss, GFP_ATOMIC)) return -ENOMEM; /* We'll try again later. */ } else { if (skb_unclone_keeptruesize(skb, GFP_ATOMIC)) return -ENOMEM; diff = tcp_skb_pcount(skb); tcp_set_skb_tso_segs(skb, cur_mss); diff -= tcp_skb_pcount(skb); if (diff) tcp_adjust_pcount(sk, skb, diff); avail_wnd = min_t(int, avail_wnd, cur_mss); if (skb->len < avail_wnd) tcp_retrans_try_collapse(sk, skb, avail_wnd); } /* RFC3168, section 6.1.1.1. ECN fallback */ if ((TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN_ECN) == TCPHDR_SYN_ECN) tcp_ecn_clear_syn(sk, skb); /* Update global and local TCP statistics. */ segs = tcp_skb_pcount(skb); TCP_ADD_STATS(sock_net(sk), TCP_MIB_RETRANSSEGS, segs); if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN) __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNRETRANS); tp->total_retrans += segs; tp->bytes_retrans += skb->len; /* make sure skb->data is aligned on arches that require it * and check if ack-trimming & collapsing extended the headroom * beyond what csum_start can cover. */ if (unlikely((NET_IP_ALIGN && ((unsigned long)skb->data & 3)) || skb_headroom(skb) >= 0xFFFF)) { struct sk_buff *nskb; tcp_skb_tsorted_save(skb) { nskb = __pskb_copy(skb, MAX_TCP_HEADER, GFP_ATOMIC); if (nskb) { nskb->dev = NULL; err = tcp_transmit_skb(sk, nskb, 0, GFP_ATOMIC); } else { err = -ENOBUFS; } } tcp_skb_tsorted_restore(skb); if (!err) { tcp_update_skb_after_send(sk, skb, tp->tcp_wstamp_ns); tcp_rate_skb_sent(sk, skb); } } else { err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC); } /* To avoid taking spuriously low RTT samples based on a timestamp * for a transmit that never happened, always mark EVER_RETRANS */ TCP_SKB_CB(skb)->sacked |= TCPCB_EVER_RETRANS; if (BPF_SOCK_OPS_TEST_FLAG(tp, BPF_SOCK_OPS_RETRANS_CB_FLAG)) tcp_call_bpf_3arg(sk, BPF_SOCK_OPS_RETRANS_CB, TCP_SKB_CB(skb)->seq, segs, err); if (likely(!err)) { trace_tcp_retransmit_skb(sk, skb); } else if (err != -EBUSY) { NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPRETRANSFAIL, segs); } return err; } int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs) { struct tcp_sock *tp = tcp_sk(sk); int err = __tcp_retransmit_skb(sk, skb, segs); if (err == 0) { #if FASTRETRANS_DEBUG > 0 if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) { net_dbg_ratelimited("retrans_out leaked\n"); } #endif TCP_SKB_CB(skb)->sacked |= TCPCB_RETRANS; tp->retrans_out += tcp_skb_pcount(skb); } /* Save stamp of the first (attempted) retransmit. */ if (!tp->retrans_stamp) tp->retrans_stamp = tcp_skb_timestamp(skb); if (tp->undo_retrans < 0) tp->undo_retrans = 0; tp->undo_retrans += tcp_skb_pcount(skb); return err; } /* This gets called after a retransmit timeout, and the initially * retransmitted data is acknowledged. It tries to continue * resending the rest of the retransmit queue, until either * we've sent it all or the congestion window limit is reached. */ void tcp_xmit_retransmit_queue(struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); struct sk_buff *skb, *rtx_head, *hole = NULL; struct tcp_sock *tp = tcp_sk(sk); bool rearm_timer = false; u32 max_segs; int mib_idx; if (!tp->packets_out) return; rtx_head = tcp_rtx_queue_head(sk); skb = tp->retransmit_skb_hint ?: rtx_head; max_segs = tcp_tso_segs(sk, tcp_current_mss(sk)); skb_rbtree_walk_from(skb) { __u8 sacked; int segs; if (tcp_pacing_check(sk)) break; /* we could do better than to assign each time */ if (!hole) tp->retransmit_skb_hint = skb; segs = tcp_snd_cwnd(tp) - tcp_packets_in_flight(tp); if (segs <= 0) break; sacked = TCP_SKB_CB(skb)->sacked; /* In case tcp_shift_skb_data() have aggregated large skbs, * we need to make sure not sending too bigs TSO packets */ segs = min_t(int, segs, max_segs); if (tp->retrans_out >= tp->lost_out) { break; } else if (!(sacked & TCPCB_LOST)) { if (!hole && !(sacked & (TCPCB_SACKED_RETRANS|TCPCB_SACKED_ACKED))) hole = skb; continue; } else { if (icsk->icsk_ca_state != TCP_CA_Loss) mib_idx = LINUX_MIB_TCPFASTRETRANS; else mib_idx = LINUX_MIB_TCPSLOWSTARTRETRANS; } if (sacked & (TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS)) continue; if (tcp_small_queue_check(sk, skb, 1)) break; if (tcp_retransmit_skb(sk, skb, segs)) break; NET_ADD_STATS(sock_net(sk), mib_idx, tcp_skb_pcount(skb)); if (tcp_in_cwnd_reduction(sk)) tp->prr_out += tcp_skb_pcount(skb); if (skb == rtx_head && icsk->icsk_pending != ICSK_TIME_REO_TIMEOUT) rearm_timer = true; } if (rearm_timer) tcp_reset_xmit_timer(sk, ICSK_TIME_RETRANS, inet_csk(sk)->icsk_rto, TCP_RTO_MAX); } /* We allow to exceed memory limits for FIN packets to expedite * connection tear down and (memory) recovery. * Otherwise tcp_send_fin() could be tempted to either delay FIN * or even be forced to close flow without any FIN. * In general, we want to allow one skb per socket to avoid hangs * with edge trigger epoll() */ void sk_forced_mem_schedule(struct sock *sk, int size) { int delta, amt; delta = size - sk->sk_forward_alloc; if (delta <= 0) return; amt = sk_mem_pages(delta); sk_forward_alloc_add(sk, amt << PAGE_SHIFT); sk_memory_allocated_add(sk, amt); if (mem_cgroup_sockets_enabled && sk->sk_memcg) mem_cgroup_charge_skmem(sk->sk_memcg, amt, gfp_memcg_charge() | __GFP_NOFAIL); } /* Send a FIN. The caller locks the socket for us. * We should try to send a FIN packet really hard, but eventually give up. */ void tcp_send_fin(struct sock *sk) { struct sk_buff *skb, *tskb, *tail = tcp_write_queue_tail(sk); struct tcp_sock *tp = tcp_sk(sk); /* Optimization, tack on the FIN if we have one skb in write queue and * this skb was not yet sent, or we are under memory pressure. * Note: in the latter case, FIN packet will be sent after a timeout, * as TCP stack thinks it has already been transmitted. */ tskb = tail; if (!tskb && tcp_under_memory_pressure(sk)) tskb = skb_rb_last(&sk->tcp_rtx_queue); if (tskb) { TCP_SKB_CB(tskb)->tcp_flags |= TCPHDR_FIN; TCP_SKB_CB(tskb)->end_seq++; tp->write_seq++; if (!tail) { /* This means tskb was already sent. * Pretend we included the FIN on previous transmit. * We need to set tp->snd_nxt to the value it would have * if FIN had been sent. This is because retransmit path * does not change tp->snd_nxt. */ WRITE_ONCE(tp->snd_nxt, tp->snd_nxt + 1); return; } } else { skb = alloc_skb_fclone(MAX_TCP_HEADER, sk->sk_allocation); if (unlikely(!skb)) return; INIT_LIST_HEAD(&skb->tcp_tsorted_anchor); skb_reserve(skb, MAX_TCP_HEADER); sk_forced_mem_schedule(sk, skb->truesize); /* FIN eats a sequence byte, write_seq advanced by tcp_queue_skb(). */ tcp_init_nondata_skb(skb, tp->write_seq, TCPHDR_ACK | TCPHDR_FIN); tcp_queue_skb(sk, skb); } __tcp_push_pending_frames(sk, tcp_current_mss(sk), TCP_NAGLE_OFF); } /* We get here when a process closes a file descriptor (either due to * an explicit close() or as a byproduct of exit()'ing) and there * was unread data in the receive queue. This behavior is recommended * by RFC 2525, section 2.17. -DaveM */ void tcp_send_active_reset(struct sock *sk, gfp_t priority) { struct sk_buff *skb; TCP_INC_STATS(sock_net(sk), TCP_MIB_OUTRSTS); /* NOTE: No TCP options attached and we never retransmit this. */ skb = alloc_skb(MAX_TCP_HEADER, priority); if (!skb) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTFAILED); return; } /* Reserve space for headers and prepare control bits. */ skb_reserve(skb, MAX_TCP_HEADER); tcp_init_nondata_skb(skb, tcp_acceptable_seq(sk), TCPHDR_ACK | TCPHDR_RST); tcp_mstamp_refresh(tcp_sk(sk)); /* Send it off. */ if (tcp_transmit_skb(sk, skb, 0, priority)) NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTFAILED); /* skb of trace_tcp_send_reset() keeps the skb that caused RST, * skb here is different to the troublesome skb, so use NULL */ trace_tcp_send_reset(sk, NULL); } /* Send a crossed SYN-ACK during socket establishment. * WARNING: This routine must only be called when we have already sent * a SYN packet that crossed the incoming SYN that caused this routine * to get called. If this assumption fails then the initial rcv_wnd * and rcv_wscale values will not be correct. */ int tcp_send_synack(struct sock *sk) { struct sk_buff *skb; skb = tcp_rtx_queue_head(sk); if (!skb || !(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) { pr_err("%s: wrong queue state\n", __func__); return -EFAULT; } if (!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_ACK)) { if (skb_cloned(skb)) { struct sk_buff *nskb; tcp_skb_tsorted_save(skb) { nskb = skb_copy(skb, GFP_ATOMIC); } tcp_skb_tsorted_restore(skb); if (!nskb) return -ENOMEM; INIT_LIST_HEAD(&nskb->tcp_tsorted_anchor); tcp_highest_sack_replace(sk, skb, nskb); tcp_rtx_queue_unlink_and_free(skb, sk); __skb_header_release(nskb); tcp_rbtree_insert(&sk->tcp_rtx_queue, nskb); sk_wmem_queued_add(sk, nskb->truesize); sk_mem_charge(sk, nskb->truesize); skb = nskb; } TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_ACK; tcp_ecn_send_synack(sk, skb); } return tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC); } /** * tcp_make_synack - Allocate one skb and build a SYNACK packet. * @sk: listener socket * @dst: dst entry attached to the SYNACK. It is consumed and caller * should not use it again. * @req: request_sock pointer * @foc: cookie for tcp fast open * @synack_type: Type of synack to prepare * @syn_skb: SYN packet just received. It could be NULL for rtx case. */ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, struct request_sock *req, struct tcp_fastopen_cookie *foc, enum tcp_synack_type synack_type, struct sk_buff *syn_skb) { struct inet_request_sock *ireq = inet_rsk(req); const struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *md5 = NULL; struct tcp_out_options opts; struct sk_buff *skb; int tcp_header_size; struct tcphdr *th; int mss; u64 now; skb = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC); if (unlikely(!skb)) { dst_release(dst); return NULL; } /* Reserve space for headers. */ skb_reserve(skb, MAX_TCP_HEADER); switch (synack_type) { case TCP_SYNACK_NORMAL: skb_set_owner_w(skb, req_to_sk(req)); break; case TCP_SYNACK_COOKIE: /* Under synflood, we do not attach skb to a socket, * to avoid false sharing. */ break; case TCP_SYNACK_FASTOPEN: /* sk is a const pointer, because we want to express multiple * cpu might call us concurrently. * sk->sk_wmem_alloc in an atomic, we can promote to rw. */ skb_set_owner_w(skb, (struct sock *)sk); break; } skb_dst_set(skb, dst); mss = tcp_mss_clamp(tp, dst_metric_advmss(dst)); memset(&opts, 0, sizeof(opts)); now = tcp_clock_ns(); #ifdef CONFIG_SYN_COOKIES if (unlikely(synack_type == TCP_SYNACK_COOKIE && ireq->tstamp_ok)) skb_set_delivery_time(skb, cookie_init_timestamp(req, now), true); else #endif { skb_set_delivery_time(skb, now, true); if (!tcp_rsk(req)->snt_synack) /* Timestamp first SYNACK */ tcp_rsk(req)->snt_synack = tcp_skb_timestamp_us(skb); } #ifdef CONFIG_TCP_MD5SIG rcu_read_lock(); md5 = tcp_rsk(req)->af_specific->req_md5_lookup(sk, req_to_sk(req)); #endif skb_set_hash(skb, READ_ONCE(tcp_rsk(req)->txhash), PKT_HASH_TYPE_L4); /* bpf program will be interested in the tcp_flags */ TCP_SKB_CB(skb)->tcp_flags = TCPHDR_SYN | TCPHDR_ACK; tcp_header_size = tcp_synack_options(sk, req, mss, skb, &opts, md5, foc, synack_type, syn_skb) + sizeof(*th); skb_push(skb, tcp_header_size); skb_reset_transport_header(skb); th = (struct tcphdr *)skb->data; memset(th, 0, sizeof(struct tcphdr)); th->syn = 1; th->ack = 1; tcp_ecn_make_synack(req, th); th->source = htons(ireq->ir_num); th->dest = ireq->ir_rmt_port; skb->mark = ireq->ir_mark; skb->ip_summed = CHECKSUM_PARTIAL; th->seq = htonl(tcp_rsk(req)->snt_isn); /* XXX data is queued and acked as is. No buffer/window check */ th->ack_seq = htonl(tcp_rsk(req)->rcv_nxt); /* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */ th->window = htons(min(req->rsk_rcv_wnd, 65535U)); tcp_options_write(th, NULL, &opts); th->doff = (tcp_header_size >> 2); TCP_INC_STATS(sock_net(sk), TCP_MIB_OUTSEGS); #ifdef CONFIG_TCP_MD5SIG /* Okay, we have all we need - do the md5 hash if needed */ if (md5) tcp_rsk(req)->af_specific->calc_md5_hash(opts.hash_location, md5, req_to_sk(req), skb); rcu_read_unlock(); #endif bpf_skops_write_hdr_opt((struct sock *)sk, skb, req, syn_skb, synack_type, &opts); skb_set_delivery_time(skb, now, true); tcp_add_tx_delay(skb, tp); return skb; } EXPORT_SYMBOL(tcp_make_synack); static void tcp_ca_dst_init(struct sock *sk, const struct dst_entry *dst) { struct inet_connection_sock *icsk = inet_csk(sk); const struct tcp_congestion_ops *ca; u32 ca_key = dst_metric(dst, RTAX_CC_ALGO); if (ca_key == TCP_CA_UNSPEC) return; rcu_read_lock(); ca = tcp_ca_find_key(ca_key); if (likely(ca && bpf_try_module_get(ca, ca->owner))) { bpf_module_put(icsk->icsk_ca_ops, icsk->icsk_ca_ops->owner); icsk->icsk_ca_dst_locked = tcp_ca_dst_locked(dst); icsk->icsk_ca_ops = ca; } rcu_read_unlock(); } /* Do all connect socket setups that can be done AF independent. */ static void tcp_connect_init(struct sock *sk) { const struct dst_entry *dst = __sk_dst_get(sk); struct tcp_sock *tp = tcp_sk(sk); __u8 rcv_wscale; u32 rcv_wnd; /* We'll fix this up when we get a response from the other end. * See tcp_input.c:tcp_rcv_state_process case TCP_SYN_SENT. */ tp->tcp_header_len = sizeof(struct tcphdr); if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_timestamps)) tp->tcp_header_len += TCPOLEN_TSTAMP_ALIGNED; /* If user gave his TCP_MAXSEG, record it to clamp */ if (tp->rx_opt.user_mss) tp->rx_opt.mss_clamp = tp->rx_opt.user_mss; tp->max_window = 0; tcp_mtup_init(sk); tcp_sync_mss(sk, dst_mtu(dst)); tcp_ca_dst_init(sk, dst); if (!tp->window_clamp) tp->window_clamp = dst_metric(dst, RTAX_WINDOW); tp->advmss = tcp_mss_clamp(tp, dst_metric_advmss(dst)); tcp_initialize_rcv_mss(sk); /* limit the window selection if the user enforce a smaller rx buffer */ if (sk->sk_userlocks & SOCK_RCVBUF_LOCK && (tp->window_clamp > tcp_full_space(sk) || tp->window_clamp == 0)) tp->window_clamp = tcp_full_space(sk); rcv_wnd = tcp_rwnd_init_bpf(sk); if (rcv_wnd == 0) rcv_wnd = dst_metric(dst, RTAX_INITRWND); tcp_select_initial_window(sk, tcp_full_space(sk), tp->advmss - (tp->rx_opt.ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0), &tp->rcv_wnd, &tp->window_clamp, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_window_scaling), &rcv_wscale, rcv_wnd); tp->rx_opt.rcv_wscale = rcv_wscale; tp->rcv_ssthresh = tp->rcv_wnd; WRITE_ONCE(sk->sk_err, 0); sock_reset_flag(sk, SOCK_DONE); tp->snd_wnd = 0; tcp_init_wl(tp, 0); tcp_write_queue_purge(sk); tp->snd_una = tp->write_seq; tp->snd_sml = tp->write_seq; tp->snd_up = tp->write_seq; WRITE_ONCE(tp->snd_nxt, tp->write_seq); if (likely(!tp->repair)) tp->rcv_nxt = 0; else tp->rcv_tstamp = tcp_jiffies32; tp->rcv_wup = tp->rcv_nxt; WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); inet_csk(sk)->icsk_rto = tcp_timeout_init(sk); inet_csk(sk)->icsk_retransmits = 0; tcp_clear_retrans(tp); } static void tcp_connect_queue_skb(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); tcb->end_seq += skb->len; __skb_header_release(skb); sk_wmem_queued_add(sk, skb->truesize); sk_mem_charge(sk, skb->truesize); WRITE_ONCE(tp->write_seq, tcb->end_seq); tp->packets_out += tcp_skb_pcount(skb); } /* Build and send a SYN with data and (cached) Fast Open cookie. However, * queue a data-only packet after the regular SYN, such that regular SYNs * are retransmitted on timeouts. Also if the remote SYN-ACK acknowledges * only the SYN sequence, the data are retransmitted in the first ACK. * If cookie is not cached or other error occurs, falls back to send a * regular SYN with Fast Open cookie request option. */ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct tcp_fastopen_request *fo = tp->fastopen_req; struct page_frag *pfrag = sk_page_frag(sk); struct sk_buff *syn_data; int space, err = 0; tp->rx_opt.mss_clamp = tp->advmss; /* If MSS is not cached */ if (!tcp_fastopen_cookie_check(sk, &tp->rx_opt.mss_clamp, &fo->cookie)) goto fallback; /* MSS for SYN-data is based on cached MSS and bounded by PMTU and * user-MSS. Reserve maximum option space for middleboxes that add * private TCP options. The cost is reduced data space in SYN :( */ tp->rx_opt.mss_clamp = tcp_mss_clamp(tp, tp->rx_opt.mss_clamp); /* Sync mss_cache after updating the mss_clamp */ tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); space = __tcp_mtu_to_mss(sk, icsk->icsk_pmtu_cookie) - MAX_TCP_OPTION_SPACE; space = min_t(size_t, space, fo->size); if (space && !skb_page_frag_refill(min_t(size_t, space, PAGE_SIZE), pfrag, sk->sk_allocation)) goto fallback; syn_data = tcp_stream_alloc_skb(sk, sk->sk_allocation, false); if (!syn_data) goto fallback; memcpy(syn_data->cb, syn->cb, sizeof(syn->cb)); if (space) { space = min_t(size_t, space, pfrag->size - pfrag->offset); space = tcp_wmem_schedule(sk, space); } if (space) { space = copy_page_from_iter(pfrag->page, pfrag->offset, space, &fo->data->msg_iter); if (unlikely(!space)) { tcp_skb_tsorted_anchor_cleanup(syn_data); kfree_skb(syn_data); goto fallback; } skb_fill_page_desc(syn_data, 0, pfrag->page, pfrag->offset, space); page_ref_inc(pfrag->page); pfrag->offset += space; skb_len_add(syn_data, space); skb_zcopy_set(syn_data, fo->uarg, NULL); } /* No more data pending in inet_wait_for_connect() */ if (space == fo->size) fo->data = NULL; fo->copied = space; tcp_connect_queue_skb(sk, syn_data); if (syn_data->len) tcp_chrono_start(sk, TCP_CHRONO_BUSY); err = tcp_transmit_skb(sk, syn_data, 1, sk->sk_allocation); skb_set_delivery_time(syn, syn_data->skb_mstamp_ns, true); /* Now full SYN+DATA was cloned and sent (or not), * remove the SYN from the original skb (syn_data) * we keep in write queue in case of a retransmit, as we * also have the SYN packet (with no data) in the same queue. */ TCP_SKB_CB(syn_data)->seq++; TCP_SKB_CB(syn_data)->tcp_flags = TCPHDR_ACK | TCPHDR_PSH; if (!err) { tp->syn_data = (fo->copied > 0); tcp_rbtree_insert(&sk->tcp_rtx_queue, syn_data); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPORIGDATASENT); goto done; } /* data was not sent, put it in write_queue */ __skb_queue_tail(&sk->sk_write_queue, syn_data); tp->packets_out -= tcp_skb_pcount(syn_data); fallback: /* Send a regular SYN with Fast Open cookie request option */ if (fo->cookie.len > 0) fo->cookie.len = 0; err = tcp_transmit_skb(sk, syn, 1, sk->sk_allocation); if (err) tp->syn_fastopen = 0; done: fo->cookie.len = -1; /* Exclude Fast Open option for SYN retries */ return err; } /* Build a SYN and send it off. */ int tcp_connect(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *buff; int err; tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_CONNECT_CB, 0, NULL); if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk)) return -EHOSTUNREACH; /* Routing failure or similar. */ tcp_connect_init(sk); if (unlikely(tp->repair)) { tcp_finish_connect(sk, NULL); return 0; } buff = tcp_stream_alloc_skb(sk, sk->sk_allocation, true); if (unlikely(!buff)) return -ENOBUFS; tcp_init_nondata_skb(buff, tp->write_seq++, TCPHDR_SYN); tcp_mstamp_refresh(tp); tp->retrans_stamp = tcp_time_stamp(tp); tcp_connect_queue_skb(sk, buff); tcp_ecn_send_syn(sk, buff); tcp_rbtree_insert(&sk->tcp_rtx_queue, buff); /* Send off SYN; include data in Fast Open. */ err = tp->fastopen_req ? tcp_send_syn_data(sk, buff) : tcp_transmit_skb(sk, buff, 1, sk->sk_allocation); if (err == -ECONNREFUSED) return err; /* We change tp->snd_nxt after the tcp_transmit_skb() call * in order to make this packet get counted in tcpOutSegs. */ WRITE_ONCE(tp->snd_nxt, tp->write_seq); tp->pushed_seq = tp->write_seq; buff = tcp_send_head(sk); if (unlikely(buff)) { WRITE_ONCE(tp->snd_nxt, TCP_SKB_CB(buff)->seq); tp->pushed_seq = TCP_SKB_CB(buff)->seq; } TCP_INC_STATS(sock_net(sk), TCP_MIB_ACTIVEOPENS); /* Timer for repeating the SYN until an answer. */ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, inet_csk(sk)->icsk_rto, TCP_RTO_MAX); return 0; } EXPORT_SYMBOL(tcp_connect); /* Send out a delayed ack, the caller does the policy checking * to see if we should even be here. See tcp_input.c:tcp_ack_snd_check() * for details. */ void tcp_send_delayed_ack(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); int ato = icsk->icsk_ack.ato; unsigned long timeout; if (ato > TCP_DELACK_MIN) { const struct tcp_sock *tp = tcp_sk(sk); int max_ato = HZ / 2; if (inet_csk_in_pingpong_mode(sk) || (icsk->icsk_ack.pending & ICSK_ACK_PUSHED)) max_ato = TCP_DELACK_MAX; /* Slow path, intersegment interval is "high". */ /* If some rtt estimate is known, use it to bound delayed ack. * Do not use inet_csk(sk)->icsk_rto here, use results of rtt measurements * directly. */ if (tp->srtt_us) { int rtt = max_t(int, usecs_to_jiffies(tp->srtt_us >> 3), TCP_DELACK_MIN); if (rtt < max_ato) max_ato = rtt; } ato = min(ato, max_ato); } ato = min_t(u32, ato, inet_csk(sk)->icsk_delack_max); /* Stay within the limit we were given */ timeout = jiffies + ato; /* Use new timeout only if there wasn't a older one earlier. */ if (icsk->icsk_ack.pending & ICSK_ACK_TIMER) { /* If delack timer is about to expire, send ACK now. */ if (time_before_eq(icsk->icsk_ack.timeout, jiffies + (ato >> 2))) { tcp_send_ack(sk); return; } if (!time_before(timeout, icsk->icsk_ack.timeout)) timeout = icsk->icsk_ack.timeout; } icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER; icsk->icsk_ack.timeout = timeout; sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout); } /* This routine sends an ack and also updates the window. */ void __tcp_send_ack(struct sock *sk, u32 rcv_nxt) { struct sk_buff *buff; /* If we have been reset, we may not send again. */ if (sk->sk_state == TCP_CLOSE) return; /* We are not putting this on the write queue, so * tcp_transmit_skb() will set the ownership to this * sock. */ buff = alloc_skb(MAX_TCP_HEADER, sk_gfp_mask(sk, GFP_ATOMIC | __GFP_NOWARN)); if (unlikely(!buff)) { struct inet_connection_sock *icsk = inet_csk(sk); unsigned long delay; delay = TCP_DELACK_MAX << icsk->icsk_ack.retry; if (delay < TCP_RTO_MAX) icsk->icsk_ack.retry++; inet_csk_schedule_ack(sk); icsk->icsk_ack.ato = TCP_ATO_MIN; inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, delay, TCP_RTO_MAX); return; } /* Reserve space for headers and prepare control bits. */ skb_reserve(buff, MAX_TCP_HEADER); tcp_init_nondata_skb(buff, tcp_acceptable_seq(sk), TCPHDR_ACK); /* We do not want pure acks influencing TCP Small Queues or fq/pacing * too much. * SKB_TRUESIZE(max(1 .. 66, MAX_TCP_HEADER)) is unfortunately ~784 */ skb_set_tcp_pure_ack(buff); /* Send it off, this clears delayed acks for us. */ __tcp_transmit_skb(sk, buff, 0, (__force gfp_t)0, rcv_nxt); } EXPORT_SYMBOL_GPL(__tcp_send_ack); void tcp_send_ack(struct sock *sk) { __tcp_send_ack(sk, tcp_sk(sk)->rcv_nxt); } /* This routine sends a packet with an out of date sequence * number. It assumes the other end will try to ack it. * * Question: what should we make while urgent mode? * 4.4BSD forces sending single byte of data. We cannot send * out of window data, because we have SND.NXT==SND.MAX... * * Current solution: to send TWO zero-length segments in urgent mode: * one is with SEG.SEQ=SND.UNA to deliver urgent pointer, another is * out-of-date with SND.UNA-1 to probe window. */ static int tcp_xmit_probe_skb(struct sock *sk, int urgent, int mib) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; /* We don't queue it, tcp_transmit_skb() sets ownership. */ skb = alloc_skb(MAX_TCP_HEADER, sk_gfp_mask(sk, GFP_ATOMIC | __GFP_NOWARN)); if (!skb) return -1; /* Reserve space for headers and set control bits. */ skb_reserve(skb, MAX_TCP_HEADER); /* Use a previous sequence. This should cause the other * end to send an ack. Don't queue or clone SKB, just * send it. */ tcp_init_nondata_skb(skb, tp->snd_una - !urgent, TCPHDR_ACK); NET_INC_STATS(sock_net(sk), mib); return tcp_transmit_skb(sk, skb, 0, (__force gfp_t)0); } /* Called from setsockopt( ... TCP_REPAIR ) */ void tcp_send_window_probe(struct sock *sk) { if (sk->sk_state == TCP_ESTABLISHED) { tcp_sk(sk)->snd_wl1 = tcp_sk(sk)->rcv_nxt - 1; tcp_mstamp_refresh(tcp_sk(sk)); tcp_xmit_probe_skb(sk, 0, LINUX_MIB_TCPWINPROBE); } } /* Initiate keepalive or window probe from timer. */ int tcp_write_wakeup(struct sock *sk, int mib) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; if (sk->sk_state == TCP_CLOSE) return -1; skb = tcp_send_head(sk); if (skb && before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(tp))) { int err; unsigned int mss = tcp_current_mss(sk); unsigned int seg_size = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq; if (before(tp->pushed_seq, TCP_SKB_CB(skb)->end_seq)) tp->pushed_seq = TCP_SKB_CB(skb)->end_seq; /* We are probing the opening of a window * but the window size is != 0 * must have been a result SWS avoidance ( sender ) */ if (seg_size < TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq || skb->len > mss) { seg_size = min(seg_size, mss); TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_PSH; if (tcp_fragment(sk, TCP_FRAG_IN_WRITE_QUEUE, skb, seg_size, mss, GFP_ATOMIC)) return -1; } else if (!tcp_skb_pcount(skb)) tcp_set_skb_tso_segs(skb, mss); TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_PSH; err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC); if (!err) tcp_event_new_data_sent(sk, skb); return err; } else { if (between(tp->snd_up, tp->snd_una + 1, tp->snd_una + 0xFFFF)) tcp_xmit_probe_skb(sk, 1, mib); return tcp_xmit_probe_skb(sk, 0, mib); } } /* A window probe timeout has occurred. If window is not closed send * a partial packet else a zero probe. */ void tcp_send_probe0(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); unsigned long timeout; int err; err = tcp_write_wakeup(sk, LINUX_MIB_TCPWINPROBE); if (tp->packets_out || tcp_write_queue_empty(sk)) { /* Cancel probe timer, if it is not required. */ icsk->icsk_probes_out = 0; icsk->icsk_backoff = 0; icsk->icsk_probes_tstamp = 0; return; } icsk->icsk_probes_out++; if (err <= 0) { if (icsk->icsk_backoff < READ_ONCE(net->ipv4.sysctl_tcp_retries2)) icsk->icsk_backoff++; timeout = tcp_probe0_when(sk, TCP_RTO_MAX); } else { /* If packet was not sent due to local congestion, * Let senders fight for local resources conservatively. */ timeout = TCP_RESOURCE_PROBE_INTERVAL; } timeout = tcp_clamp_probe0_to_user_timeout(sk, timeout); tcp_reset_xmit_timer(sk, ICSK_TIME_PROBE0, timeout, TCP_RTO_MAX); } int tcp_rtx_synack(const struct sock *sk, struct request_sock *req) { const struct tcp_request_sock_ops *af_ops = tcp_rsk(req)->af_specific; struct flowi fl; int res; /* Paired with WRITE_ONCE() in sock_setsockopt() */ if (READ_ONCE(sk->sk_txrehash) == SOCK_TXREHASH_ENABLED) WRITE_ONCE(tcp_rsk(req)->txhash, net_tx_rndhash()); res = af_ops->send_synack(sk, NULL, &fl, req, NULL, TCP_SYNACK_NORMAL, NULL); if (!res) { TCP_INC_STATS(sock_net(sk), TCP_MIB_RETRANSSEGS); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNRETRANS); if (unlikely(tcp_passive_fastopen(sk))) { /* sk has const attribute because listeners are lockless. * However in this case, we are dealing with a passive fastopen * socket thus we can change total_retrans value. */ tcp_sk_rw(sk)->total_retrans++; } trace_tcp_retransmit_synack(sk, req); } return res; } EXPORT_SYMBOL(tcp_rtx_synack);
linux-master
net/ipv4/tcp_output.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * RAW - implementation of IP "raw" sockets. * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * * Fixes: * Alan Cox : verify_area() fixed up * Alan Cox : ICMP error handling * Alan Cox : EMSGSIZE if you send too big a packet * Alan Cox : Now uses generic datagrams and shared * skbuff library. No more peek crashes, * no more backlogs * Alan Cox : Checks sk->broadcast. * Alan Cox : Uses skb_free_datagram/skb_copy_datagram * Alan Cox : Raw passes ip options too * Alan Cox : Setsocketopt added * Alan Cox : Fixed error return for broadcasts * Alan Cox : Removed wake_up calls * Alan Cox : Use ttl/tos * Alan Cox : Cleaned up old debugging * Alan Cox : Use new kernel side addresses * Arnt Gulbrandsen : Fixed MSG_DONTROUTE in raw sockets. * Alan Cox : BSD style RAW socket demultiplexing. * Alan Cox : Beginnings of mrouted support. * Alan Cox : Added IP_HDRINCL option. * Alan Cox : Skip broadcast check if BSDism set. * David S. Miller : New socket lookup architecture. */ #include <linux/types.h> #include <linux/atomic.h> #include <asm/byteorder.h> #include <asm/current.h> #include <linux/uaccess.h> #include <asm/ioctls.h> #include <linux/stddef.h> #include <linux/slab.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/export.h> #include <linux/spinlock.h> #include <linux/sockios.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/mroute.h> #include <linux/netdevice.h> #include <linux/in_route.h> #include <linux/route.h> #include <linux/skbuff.h> #include <linux/igmp.h> #include <net/net_namespace.h> #include <net/dst.h> #include <net/sock.h> #include <linux/ip.h> #include <linux/net.h> #include <net/ip.h> #include <net/icmp.h> #include <net/udp.h> #include <net/raw.h> #include <net/snmp.h> #include <net/tcp_states.h> #include <net/inet_common.h> #include <net/checksum.h> #include <net/xfrm.h> #include <linux/rtnetlink.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/netfilter.h> #include <linux/netfilter_ipv4.h> #include <linux/compat.h> #include <linux/uio.h> struct raw_frag_vec { struct msghdr *msg; union { struct icmphdr icmph; char c[1]; } hdr; int hlen; }; struct raw_hashinfo raw_v4_hashinfo; EXPORT_SYMBOL_GPL(raw_v4_hashinfo); int raw_hash_sk(struct sock *sk) { struct raw_hashinfo *h = sk->sk_prot->h.raw_hash; struct hlist_head *hlist; hlist = &h->ht[raw_hashfunc(sock_net(sk), inet_sk(sk)->inet_num)]; spin_lock(&h->lock); sk_add_node_rcu(sk, hlist); sock_set_flag(sk, SOCK_RCU_FREE); spin_unlock(&h->lock); sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); return 0; } EXPORT_SYMBOL_GPL(raw_hash_sk); void raw_unhash_sk(struct sock *sk) { struct raw_hashinfo *h = sk->sk_prot->h.raw_hash; spin_lock(&h->lock); if (sk_del_node_init_rcu(sk)) sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); spin_unlock(&h->lock); } EXPORT_SYMBOL_GPL(raw_unhash_sk); bool raw_v4_match(struct net *net, const struct sock *sk, unsigned short num, __be32 raddr, __be32 laddr, int dif, int sdif) { const struct inet_sock *inet = inet_sk(sk); if (net_eq(sock_net(sk), net) && inet->inet_num == num && !(inet->inet_daddr && inet->inet_daddr != raddr) && !(inet->inet_rcv_saddr && inet->inet_rcv_saddr != laddr) && raw_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif)) return true; return false; } EXPORT_SYMBOL_GPL(raw_v4_match); /* * 0 - deliver * 1 - block */ static int icmp_filter(const struct sock *sk, const struct sk_buff *skb) { struct icmphdr _hdr; const struct icmphdr *hdr; hdr = skb_header_pointer(skb, skb_transport_offset(skb), sizeof(_hdr), &_hdr); if (!hdr) return 1; if (hdr->type < 32) { __u32 data = raw_sk(sk)->filter.data; return ((1U << hdr->type) & data) != 0; } /* Do not block unknown ICMP types */ return 0; } /* IP input processing comes here for RAW socket delivery. * Caller owns SKB, so we must make clones. * * RFC 1122: SHOULD pass TOS value up to the transport layer. * -> It does. And not only TOS, but all IP header. */ static int raw_v4_input(struct net *net, struct sk_buff *skb, const struct iphdr *iph, int hash) { int sdif = inet_sdif(skb); struct hlist_head *hlist; int dif = inet_iif(skb); int delivered = 0; struct sock *sk; hlist = &raw_v4_hashinfo.ht[hash]; rcu_read_lock(); sk_for_each_rcu(sk, hlist) { if (!raw_v4_match(net, sk, iph->protocol, iph->saddr, iph->daddr, dif, sdif)) continue; delivered = 1; if ((iph->protocol != IPPROTO_ICMP || !icmp_filter(sk, skb)) && ip_mc_sf_allow(sk, iph->daddr, iph->saddr, skb->dev->ifindex, sdif)) { struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); /* Not releasing hash table! */ if (clone) raw_rcv(sk, clone); } } rcu_read_unlock(); return delivered; } int raw_local_deliver(struct sk_buff *skb, int protocol) { struct net *net = dev_net(skb->dev); return raw_v4_input(net, skb, ip_hdr(skb), raw_hashfunc(net, protocol)); } static void raw_err(struct sock *sk, struct sk_buff *skb, u32 info) { struct inet_sock *inet = inet_sk(sk); const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; int harderr = 0; bool recverr; int err = 0; if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) ipv4_sk_update_pmtu(skb, sk, info); else if (type == ICMP_REDIRECT) { ipv4_sk_redirect(skb, sk); return; } /* Report error on raw socket, if: 1. User requested ip_recverr. 2. Socket is connected (otherwise the error indication is useless without ip_recverr and error is hard. */ recverr = inet_test_bit(RECVERR, sk); if (!recverr && sk->sk_state != TCP_ESTABLISHED) return; switch (type) { default: case ICMP_TIME_EXCEEDED: err = EHOSTUNREACH; break; case ICMP_SOURCE_QUENCH: return; case ICMP_PARAMETERPROB: err = EPROTO; harderr = 1; break; case ICMP_DEST_UNREACH: err = EHOSTUNREACH; if (code > NR_ICMP_UNREACH) break; if (code == ICMP_FRAG_NEEDED) { harderr = inet->pmtudisc != IP_PMTUDISC_DONT; err = EMSGSIZE; } else { err = icmp_err_convert[code].errno; harderr = icmp_err_convert[code].fatal; } } if (recverr) { const struct iphdr *iph = (const struct iphdr *)skb->data; u8 *payload = skb->data + (iph->ihl << 2); if (inet_test_bit(HDRINCL, sk)) payload = skb->data; ip_icmp_error(sk, skb, err, 0, info, payload); } if (recverr || harderr) { sk->sk_err = err; sk_error_report(sk); } } void raw_icmp_error(struct sk_buff *skb, int protocol, u32 info) { struct net *net = dev_net(skb->dev); int dif = skb->dev->ifindex; int sdif = inet_sdif(skb); struct hlist_head *hlist; const struct iphdr *iph; struct sock *sk; int hash; hash = raw_hashfunc(net, protocol); hlist = &raw_v4_hashinfo.ht[hash]; rcu_read_lock(); sk_for_each_rcu(sk, hlist) { iph = (const struct iphdr *)skb->data; if (!raw_v4_match(net, sk, iph->protocol, iph->daddr, iph->saddr, dif, sdif)) continue; raw_err(sk, skb, info); } rcu_read_unlock(); } static int raw_rcv_skb(struct sock *sk, struct sk_buff *skb) { enum skb_drop_reason reason; /* Charge it to the socket. */ ipv4_pktinfo_prepare(sk, skb); if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0) { kfree_skb_reason(skb, reason); return NET_RX_DROP; } return NET_RX_SUCCESS; } int raw_rcv(struct sock *sk, struct sk_buff *skb) { if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) { atomic_inc(&sk->sk_drops); kfree_skb_reason(skb, SKB_DROP_REASON_XFRM_POLICY); return NET_RX_DROP; } nf_reset_ct(skb); skb_push(skb, skb->data - skb_network_header(skb)); raw_rcv_skb(sk, skb); return 0; } static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4, struct msghdr *msg, size_t length, struct rtable **rtp, unsigned int flags, const struct sockcm_cookie *sockc) { struct inet_sock *inet = inet_sk(sk); struct net *net = sock_net(sk); struct iphdr *iph; struct sk_buff *skb; unsigned int iphlen; int err; struct rtable *rt = *rtp; int hlen, tlen; if (length > rt->dst.dev->mtu) { ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, rt->dst.dev->mtu); return -EMSGSIZE; } if (length < sizeof(struct iphdr)) return -EINVAL; if (flags&MSG_PROBE) goto out; hlen = LL_RESERVED_SPACE(rt->dst.dev); tlen = rt->dst.dev->needed_tailroom; skb = sock_alloc_send_skb(sk, length + hlen + tlen + 15, flags & MSG_DONTWAIT, &err); if (!skb) goto error; skb_reserve(skb, hlen); skb->priority = READ_ONCE(sk->sk_priority); skb->mark = sockc->mark; skb->tstamp = sockc->transmit_time; skb_dst_set(skb, &rt->dst); *rtp = NULL; skb_reset_network_header(skb); iph = ip_hdr(skb); skb_put(skb, length); skb->ip_summed = CHECKSUM_NONE; skb_setup_tx_timestamp(skb, sockc->tsflags); if (flags & MSG_CONFIRM) skb_set_dst_pending_confirm(skb, 1); skb->transport_header = skb->network_header; err = -EFAULT; if (memcpy_from_msg(iph, msg, length)) goto error_free; iphlen = iph->ihl * 4; /* * We don't want to modify the ip header, but we do need to * be sure that it won't cause problems later along the network * stack. Specifically we want to make sure that iph->ihl is a * sane value. If ihl points beyond the length of the buffer passed * in, reject the frame as invalid */ err = -EINVAL; if (iphlen > length) goto error_free; if (iphlen >= sizeof(*iph)) { if (!iph->saddr) iph->saddr = fl4->saddr; iph->check = 0; iph->tot_len = htons(length); if (!iph->id) ip_select_ident(net, skb, NULL); iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); skb->transport_header += iphlen; if (iph->protocol == IPPROTO_ICMP && length >= iphlen + sizeof(struct icmphdr)) icmp_out_count(net, ((struct icmphdr *) skb_transport_header(skb))->type); } err = NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk, skb, NULL, rt->dst.dev, dst_output); if (err > 0) err = net_xmit_errno(err); if (err) goto error; out: return 0; error_free: kfree_skb(skb); error: IP_INC_STATS(net, IPSTATS_MIB_OUTDISCARDS); if (err == -ENOBUFS && !inet_test_bit(RECVERR, sk)) err = 0; return err; } static int raw_probe_proto_opt(struct raw_frag_vec *rfv, struct flowi4 *fl4) { int err; if (fl4->flowi4_proto != IPPROTO_ICMP) return 0; /* We only need the first two bytes. */ rfv->hlen = 2; err = memcpy_from_msg(rfv->hdr.c, rfv->msg, rfv->hlen); if (err) return err; fl4->fl4_icmp_type = rfv->hdr.icmph.type; fl4->fl4_icmp_code = rfv->hdr.icmph.code; return 0; } static int raw_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb) { struct raw_frag_vec *rfv = from; if (offset < rfv->hlen) { int copy = min(rfv->hlen - offset, len); if (skb->ip_summed == CHECKSUM_PARTIAL) memcpy(to, rfv->hdr.c + offset, copy); else skb->csum = csum_block_add( skb->csum, csum_partial_copy_nocheck(rfv->hdr.c + offset, to, copy), odd); odd = 0; offset += copy; to += copy; len -= copy; if (!len) return 0; } offset -= rfv->hlen; return ip_generic_getfrag(rfv->msg, to, offset, len, odd, skb); } static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) { struct inet_sock *inet = inet_sk(sk); struct net *net = sock_net(sk); struct ipcm_cookie ipc; struct rtable *rt = NULL; struct flowi4 fl4; u8 tos, scope; int free = 0; __be32 daddr; __be32 saddr; int err; struct ip_options_data opt_copy; struct raw_frag_vec rfv; int hdrincl; err = -EMSGSIZE; if (len > 0xFFFF) goto out; hdrincl = inet_test_bit(HDRINCL, sk); /* * Check the flags. */ err = -EOPNOTSUPP; if (msg->msg_flags & MSG_OOB) /* Mirror BSD error message */ goto out; /* compatibility */ /* * Get and verify the address. */ if (msg->msg_namelen) { DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name); err = -EINVAL; if (msg->msg_namelen < sizeof(*usin)) goto out; if (usin->sin_family != AF_INET) { pr_info_once("%s: %s forgot to set AF_INET. Fix it!\n", __func__, current->comm); err = -EAFNOSUPPORT; if (usin->sin_family) goto out; } daddr = usin->sin_addr.s_addr; /* ANK: I did not forget to get protocol from port field. * I just do not know, who uses this weirdness. * IP_HDRINCL is much more convenient. */ } else { err = -EDESTADDRREQ; if (sk->sk_state != TCP_ESTABLISHED) goto out; daddr = inet->inet_daddr; } ipcm_init_sk(&ipc, inet); /* Keep backward compat */ if (hdrincl) ipc.protocol = IPPROTO_RAW; if (msg->msg_controllen) { err = ip_cmsg_send(sk, msg, &ipc, false); if (unlikely(err)) { kfree(ipc.opt); goto out; } if (ipc.opt) free = 1; } saddr = ipc.addr; ipc.addr = daddr; if (!ipc.opt) { struct ip_options_rcu *inet_opt; rcu_read_lock(); inet_opt = rcu_dereference(inet->inet_opt); if (inet_opt) { memcpy(&opt_copy, inet_opt, sizeof(*inet_opt) + inet_opt->opt.optlen); ipc.opt = &opt_copy.opt; } rcu_read_unlock(); } if (ipc.opt) { err = -EINVAL; /* Linux does not mangle headers on raw sockets, * so that IP options + IP_HDRINCL is non-sense. */ if (hdrincl) goto done; if (ipc.opt->opt.srr) { if (!daddr) goto done; daddr = ipc.opt->opt.faddr; } } tos = get_rttos(&ipc, inet); scope = ip_sendmsg_scope(inet, &ipc, msg); if (ipv4_is_multicast(daddr)) { if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif)) ipc.oif = inet->mc_index; if (!saddr) saddr = inet->mc_addr; } else if (!ipc.oif) { ipc.oif = inet->uc_index; } else if (ipv4_is_lbcast(daddr) && inet->uc_index) { /* oif is set, packet is to local broadcast * and uc_index is set. oif is most likely set * by sk_bound_dev_if. If uc_index != oif check if the * oif is an L3 master and uc_index is an L3 slave. * If so, we want to allow the send using the uc_index. */ if (ipc.oif != inet->uc_index && ipc.oif == l3mdev_master_ifindex_by_index(sock_net(sk), inet->uc_index)) { ipc.oif = inet->uc_index; } } flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos, scope, hdrincl ? ipc.protocol : sk->sk_protocol, inet_sk_flowi_flags(sk) | (hdrincl ? FLOWI_FLAG_KNOWN_NH : 0), daddr, saddr, 0, 0, sk->sk_uid); if (!hdrincl) { rfv.msg = msg; rfv.hlen = 0; err = raw_probe_proto_opt(&rfv, &fl4); if (err) goto done; } security_sk_classify_flow(sk, flowi4_to_flowi_common(&fl4)); rt = ip_route_output_flow(net, &fl4, sk); if (IS_ERR(rt)) { err = PTR_ERR(rt); rt = NULL; goto done; } err = -EACCES; if (rt->rt_flags & RTCF_BROADCAST && !sock_flag(sk, SOCK_BROADCAST)) goto done; if (msg->msg_flags & MSG_CONFIRM) goto do_confirm; back_from_confirm: if (hdrincl) err = raw_send_hdrinc(sk, &fl4, msg, len, &rt, msg->msg_flags, &ipc.sockc); else { if (!ipc.addr) ipc.addr = fl4.daddr; lock_sock(sk); err = ip_append_data(sk, &fl4, raw_getfrag, &rfv, len, 0, &ipc, &rt, msg->msg_flags); if (err) ip_flush_pending_frames(sk); else if (!(msg->msg_flags & MSG_MORE)) { err = ip_push_pending_frames(sk, &fl4); if (err == -ENOBUFS && !inet_test_bit(RECVERR, sk)) err = 0; } release_sock(sk); } done: if (free) kfree(ipc.opt); ip_rt_put(rt); out: if (err < 0) return err; return len; do_confirm: if (msg->msg_flags & MSG_PROBE) dst_confirm_neigh(&rt->dst, &fl4.daddr); if (!(msg->msg_flags & MSG_PROBE) || len) goto back_from_confirm; err = 0; goto done; } static void raw_close(struct sock *sk, long timeout) { /* * Raw sockets may have direct kernel references. Kill them. */ ip_ra_control(sk, 0, NULL); sk_common_release(sk); } static void raw_destroy(struct sock *sk) { lock_sock(sk); ip_flush_pending_frames(sk); release_sock(sk); } /* This gets rid of all the nasties in af_inet. -DaveM */ static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) { struct inet_sock *inet = inet_sk(sk); struct sockaddr_in *addr = (struct sockaddr_in *) uaddr; struct net *net = sock_net(sk); u32 tb_id = RT_TABLE_LOCAL; int ret = -EINVAL; int chk_addr_ret; lock_sock(sk); if (sk->sk_state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_in)) goto out; if (sk->sk_bound_dev_if) tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id; chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id); ret = -EADDRNOTAVAIL; if (!inet_addr_valid_or_nonlocal(net, inet, addr->sin_addr.s_addr, chk_addr_ret)) goto out; inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr; if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST) inet->inet_saddr = 0; /* Use device */ sk_dst_reset(sk); ret = 0; out: release_sock(sk); return ret; } /* * This should be easy, if there is something there * we return it, otherwise we block. */ static int raw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { struct inet_sock *inet = inet_sk(sk); size_t copied = 0; int err = -EOPNOTSUPP; DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); struct sk_buff *skb; if (flags & MSG_OOB) goto out; if (flags & MSG_ERRQUEUE) { err = ip_recv_error(sk, msg, len, addr_len); goto out; } skb = skb_recv_datagram(sk, flags, &err); if (!skb) goto out; copied = skb->len; if (len < copied) { msg->msg_flags |= MSG_TRUNC; copied = len; } err = skb_copy_datagram_msg(skb, 0, msg, copied); if (err) goto done; sock_recv_cmsgs(msg, sk, skb); /* Copy the address. */ if (sin) { sin->sin_family = AF_INET; sin->sin_addr.s_addr = ip_hdr(skb)->saddr; sin->sin_port = 0; memset(&sin->sin_zero, 0, sizeof(sin->sin_zero)); *addr_len = sizeof(*sin); } if (inet_cmsg_flags(inet)) ip_cmsg_recv(msg, skb); if (flags & MSG_TRUNC) copied = skb->len; done: skb_free_datagram(sk, skb); out: if (err) return err; return copied; } static int raw_sk_init(struct sock *sk) { struct raw_sock *rp = raw_sk(sk); if (inet_sk(sk)->inet_num == IPPROTO_ICMP) memset(&rp->filter, 0, sizeof(rp->filter)); return 0; } static int raw_seticmpfilter(struct sock *sk, sockptr_t optval, int optlen) { if (optlen > sizeof(struct icmp_filter)) optlen = sizeof(struct icmp_filter); if (copy_from_sockptr(&raw_sk(sk)->filter, optval, optlen)) return -EFAULT; return 0; } static int raw_geticmpfilter(struct sock *sk, char __user *optval, int __user *optlen) { int len, ret = -EFAULT; if (get_user(len, optlen)) goto out; ret = -EINVAL; if (len < 0) goto out; if (len > sizeof(struct icmp_filter)) len = sizeof(struct icmp_filter); ret = -EFAULT; if (put_user(len, optlen) || copy_to_user(optval, &raw_sk(sk)->filter, len)) goto out; ret = 0; out: return ret; } static int do_raw_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { if (optname == ICMP_FILTER) { if (inet_sk(sk)->inet_num != IPPROTO_ICMP) return -EOPNOTSUPP; else return raw_seticmpfilter(sk, optval, optlen); } return -ENOPROTOOPT; } static int raw_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { if (level != SOL_RAW) return ip_setsockopt(sk, level, optname, optval, optlen); return do_raw_setsockopt(sk, level, optname, optval, optlen); } static int do_raw_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { if (optname == ICMP_FILTER) { if (inet_sk(sk)->inet_num != IPPROTO_ICMP) return -EOPNOTSUPP; else return raw_geticmpfilter(sk, optval, optlen); } return -ENOPROTOOPT; } static int raw_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { if (level != SOL_RAW) return ip_getsockopt(sk, level, optname, optval, optlen); return do_raw_getsockopt(sk, level, optname, optval, optlen); } static int raw_ioctl(struct sock *sk, int cmd, int *karg) { switch (cmd) { case SIOCOUTQ: { *karg = sk_wmem_alloc_get(sk); return 0; } case SIOCINQ: { struct sk_buff *skb; spin_lock_bh(&sk->sk_receive_queue.lock); skb = skb_peek(&sk->sk_receive_queue); if (skb) *karg = skb->len; else *karg = 0; spin_unlock_bh(&sk->sk_receive_queue.lock); return 0; } default: #ifdef CONFIG_IP_MROUTE return ipmr_ioctl(sk, cmd, karg); #else return -ENOIOCTLCMD; #endif } } #ifdef CONFIG_COMPAT static int compat_raw_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg) { switch (cmd) { case SIOCOUTQ: case SIOCINQ: return -ENOIOCTLCMD; default: #ifdef CONFIG_IP_MROUTE return ipmr_compat_ioctl(sk, cmd, compat_ptr(arg)); #else return -ENOIOCTLCMD; #endif } } #endif int raw_abort(struct sock *sk, int err) { lock_sock(sk); sk->sk_err = err; sk_error_report(sk); __udp_disconnect(sk, 0); release_sock(sk); return 0; } EXPORT_SYMBOL_GPL(raw_abort); struct proto raw_prot = { .name = "RAW", .owner = THIS_MODULE, .close = raw_close, .destroy = raw_destroy, .connect = ip4_datagram_connect, .disconnect = __udp_disconnect, .ioctl = raw_ioctl, .init = raw_sk_init, .setsockopt = raw_setsockopt, .getsockopt = raw_getsockopt, .sendmsg = raw_sendmsg, .recvmsg = raw_recvmsg, .bind = raw_bind, .backlog_rcv = raw_rcv_skb, .release_cb = ip4_datagram_release_cb, .hash = raw_hash_sk, .unhash = raw_unhash_sk, .obj_size = sizeof(struct raw_sock), .useroffset = offsetof(struct raw_sock, filter), .usersize = sizeof_field(struct raw_sock, filter), .h.raw_hash = &raw_v4_hashinfo, #ifdef CONFIG_COMPAT .compat_ioctl = compat_raw_ioctl, #endif .diag_destroy = raw_abort, }; #ifdef CONFIG_PROC_FS static struct sock *raw_get_first(struct seq_file *seq, int bucket) { struct raw_hashinfo *h = pde_data(file_inode(seq->file)); struct raw_iter_state *state = raw_seq_private(seq); struct hlist_head *hlist; struct sock *sk; for (state->bucket = bucket; state->bucket < RAW_HTABLE_SIZE; ++state->bucket) { hlist = &h->ht[state->bucket]; sk_for_each(sk, hlist) { if (sock_net(sk) == seq_file_net(seq)) return sk; } } return NULL; } static struct sock *raw_get_next(struct seq_file *seq, struct sock *sk) { struct raw_iter_state *state = raw_seq_private(seq); do { sk = sk_next(sk); } while (sk && sock_net(sk) != seq_file_net(seq)); if (!sk) return raw_get_first(seq, state->bucket + 1); return sk; } static struct sock *raw_get_idx(struct seq_file *seq, loff_t pos) { struct sock *sk = raw_get_first(seq, 0); if (sk) while (pos && (sk = raw_get_next(seq, sk)) != NULL) --pos; return pos ? NULL : sk; } void *raw_seq_start(struct seq_file *seq, loff_t *pos) __acquires(&h->lock) { struct raw_hashinfo *h = pde_data(file_inode(seq->file)); spin_lock(&h->lock); return *pos ? raw_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; } EXPORT_SYMBOL_GPL(raw_seq_start); void *raw_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct sock *sk; if (v == SEQ_START_TOKEN) sk = raw_get_first(seq, 0); else sk = raw_get_next(seq, v); ++*pos; return sk; } EXPORT_SYMBOL_GPL(raw_seq_next); void raw_seq_stop(struct seq_file *seq, void *v) __releases(&h->lock) { struct raw_hashinfo *h = pde_data(file_inode(seq->file)); spin_unlock(&h->lock); } EXPORT_SYMBOL_GPL(raw_seq_stop); static void raw_sock_seq_show(struct seq_file *seq, struct sock *sp, int i) { struct inet_sock *inet = inet_sk(sp); __be32 dest = inet->inet_daddr, src = inet->inet_rcv_saddr; __u16 destp = 0, srcp = inet->inet_num; seq_printf(seq, "%4d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n", i, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), 0, 0L, 0, from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 0, sock_i_ino(sp), refcount_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); } static int raw_seq_show(struct seq_file *seq, void *v) { if (v == SEQ_START_TOKEN) seq_printf(seq, " sl local_address rem_address st tx_queue " "rx_queue tr tm->when retrnsmt uid timeout " "inode ref pointer drops\n"); else raw_sock_seq_show(seq, v, raw_seq_private(seq)->bucket); return 0; } static const struct seq_operations raw_seq_ops = { .start = raw_seq_start, .next = raw_seq_next, .stop = raw_seq_stop, .show = raw_seq_show, }; static __net_init int raw_init_net(struct net *net) { if (!proc_create_net_data("raw", 0444, net->proc_net, &raw_seq_ops, sizeof(struct raw_iter_state), &raw_v4_hashinfo)) return -ENOMEM; return 0; } static __net_exit void raw_exit_net(struct net *net) { remove_proc_entry("raw", net->proc_net); } static __net_initdata struct pernet_operations raw_net_ops = { .init = raw_init_net, .exit = raw_exit_net, }; int __init raw_proc_init(void) { return register_pernet_subsys(&raw_net_ops); } void __init raw_proc_exit(void) { unregister_pernet_subsys(&raw_net_ops); } #endif /* CONFIG_PROC_FS */ static void raw_sysctl_init_net(struct net *net) { #ifdef CONFIG_NET_L3_MASTER_DEV net->ipv4.sysctl_raw_l3mdev_accept = 1; #endif } static int __net_init raw_sysctl_init(struct net *net) { raw_sysctl_init_net(net); return 0; } static struct pernet_operations __net_initdata raw_sysctl_ops = { .init = raw_sysctl_init, }; void __init raw_init(void) { raw_sysctl_init_net(&init_net); if (register_pernet_subsys(&raw_sysctl_ops)) panic("RAW: failed to init sysctl parameters.\n"); }
linux-master
net/ipv4/raw.c
/* Bottleneck Bandwidth and RTT (BBR) congestion control * * BBR congestion control computes the sending rate based on the delivery * rate (throughput) estimated from ACKs. In a nutshell: * * On each ACK, update our model of the network path: * bottleneck_bandwidth = windowed_max(delivered / elapsed, 10 round trips) * min_rtt = windowed_min(rtt, 10 seconds) * pacing_rate = pacing_gain * bottleneck_bandwidth * cwnd = max(cwnd_gain * bottleneck_bandwidth * min_rtt, 4) * * The core algorithm does not react directly to packet losses or delays, * although BBR may adjust the size of next send per ACK when loss is * observed, or adjust the sending rate if it estimates there is a * traffic policer, in order to keep the drop rate reasonable. * * Here is a state transition diagram for BBR: * * | * V * +---> STARTUP ----+ * | | | * | V | * | DRAIN ----+ * | | | * | V | * +---> PROBE_BW ----+ * | ^ | | * | | | | * | +----+ | * | | * +---- PROBE_RTT <--+ * * A BBR flow starts in STARTUP, and ramps up its sending rate quickly. * When it estimates the pipe is full, it enters DRAIN to drain the queue. * In steady state a BBR flow only uses PROBE_BW and PROBE_RTT. * A long-lived BBR flow spends the vast majority of its time remaining * (repeatedly) in PROBE_BW, fully probing and utilizing the pipe's bandwidth * in a fair manner, with a small, bounded queue. *If* a flow has been * continuously sending for the entire min_rtt window, and hasn't seen an RTT * sample that matches or decreases its min_rtt estimate for 10 seconds, then * it briefly enters PROBE_RTT to cut inflight to a minimum value to re-probe * the path's two-way propagation delay (min_rtt). When exiting PROBE_RTT, if * we estimated that we reached the full bw of the pipe then we enter PROBE_BW; * otherwise we enter STARTUP to try to fill the pipe. * * BBR is described in detail in: * "BBR: Congestion-Based Congestion Control", * Neal Cardwell, Yuchung Cheng, C. Stephen Gunn, Soheil Hassas Yeganeh, * Van Jacobson. ACM Queue, Vol. 14 No. 5, September-October 2016. * * There is a public e-mail list for discussing BBR development and testing: * https://groups.google.com/forum/#!forum/bbr-dev * * NOTE: BBR might be used with the fq qdisc ("man tc-fq") with pacing enabled, * otherwise TCP stack falls back to an internal pacing using one high * resolution timer per TCP socket and may use more resources. */ #include <linux/btf.h> #include <linux/btf_ids.h> #include <linux/module.h> #include <net/tcp.h> #include <linux/inet_diag.h> #include <linux/inet.h> #include <linux/random.h> #include <linux/win_minmax.h> /* Scale factor for rate in pkt/uSec unit to avoid truncation in bandwidth * estimation. The rate unit ~= (1500 bytes / 1 usec / 2^24) ~= 715 bps. * This handles bandwidths from 0.06pps (715bps) to 256Mpps (3Tbps) in a u32. * Since the minimum window is >=4 packets, the lower bound isn't * an issue. The upper bound isn't an issue with existing technologies. */ #define BW_SCALE 24 #define BW_UNIT (1 << BW_SCALE) #define BBR_SCALE 8 /* scaling factor for fractions in BBR (e.g. gains) */ #define BBR_UNIT (1 << BBR_SCALE) /* BBR has the following modes for deciding how fast to send: */ enum bbr_mode { BBR_STARTUP, /* ramp up sending rate rapidly to fill pipe */ BBR_DRAIN, /* drain any queue created during startup */ BBR_PROBE_BW, /* discover, share bw: pace around estimated bw */ BBR_PROBE_RTT, /* cut inflight to min to probe min_rtt */ }; /* BBR congestion control block */ struct bbr { u32 min_rtt_us; /* min RTT in min_rtt_win_sec window */ u32 min_rtt_stamp; /* timestamp of min_rtt_us */ u32 probe_rtt_done_stamp; /* end time for BBR_PROBE_RTT mode */ struct minmax bw; /* Max recent delivery rate in pkts/uS << 24 */ u32 rtt_cnt; /* count of packet-timed rounds elapsed */ u32 next_rtt_delivered; /* scb->tx.delivered at end of round */ u64 cycle_mstamp; /* time of this cycle phase start */ u32 mode:3, /* current bbr_mode in state machine */ prev_ca_state:3, /* CA state on previous ACK */ packet_conservation:1, /* use packet conservation? */ round_start:1, /* start of packet-timed tx->ack round? */ idle_restart:1, /* restarting after idle? */ probe_rtt_round_done:1, /* a BBR_PROBE_RTT round at 4 pkts? */ unused:13, lt_is_sampling:1, /* taking long-term ("LT") samples now? */ lt_rtt_cnt:7, /* round trips in long-term interval */ lt_use_bw:1; /* use lt_bw as our bw estimate? */ u32 lt_bw; /* LT est delivery rate in pkts/uS << 24 */ u32 lt_last_delivered; /* LT intvl start: tp->delivered */ u32 lt_last_stamp; /* LT intvl start: tp->delivered_mstamp */ u32 lt_last_lost; /* LT intvl start: tp->lost */ u32 pacing_gain:10, /* current gain for setting pacing rate */ cwnd_gain:10, /* current gain for setting cwnd */ full_bw_reached:1, /* reached full bw in Startup? */ full_bw_cnt:2, /* number of rounds without large bw gains */ cycle_idx:3, /* current index in pacing_gain cycle array */ has_seen_rtt:1, /* have we seen an RTT sample yet? */ unused_b:5; u32 prior_cwnd; /* prior cwnd upon entering loss recovery */ u32 full_bw; /* recent bw, to estimate if pipe is full */ /* For tracking ACK aggregation: */ u64 ack_epoch_mstamp; /* start of ACK sampling epoch */ u16 extra_acked[2]; /* max excess data ACKed in epoch */ u32 ack_epoch_acked:20, /* packets (S)ACKed in sampling epoch */ extra_acked_win_rtts:5, /* age of extra_acked, in round trips */ extra_acked_win_idx:1, /* current index in extra_acked array */ unused_c:6; }; #define CYCLE_LEN 8 /* number of phases in a pacing gain cycle */ /* Window length of bw filter (in rounds): */ static const int bbr_bw_rtts = CYCLE_LEN + 2; /* Window length of min_rtt filter (in sec): */ static const u32 bbr_min_rtt_win_sec = 10; /* Minimum time (in ms) spent at bbr_cwnd_min_target in BBR_PROBE_RTT mode: */ static const u32 bbr_probe_rtt_mode_ms = 200; /* Skip TSO below the following bandwidth (bits/sec): */ static const int bbr_min_tso_rate = 1200000; /* Pace at ~1% below estimated bw, on average, to reduce queue at bottleneck. * In order to help drive the network toward lower queues and low latency while * maintaining high utilization, the average pacing rate aims to be slightly * lower than the estimated bandwidth. This is an important aspect of the * design. */ static const int bbr_pacing_margin_percent = 1; /* We use a high_gain value of 2/ln(2) because it's the smallest pacing gain * that will allow a smoothly increasing pacing rate that will double each RTT * and send the same number of packets per RTT that an un-paced, slow-starting * Reno or CUBIC flow would: */ static const int bbr_high_gain = BBR_UNIT * 2885 / 1000 + 1; /* The pacing gain of 1/high_gain in BBR_DRAIN is calculated to typically drain * the queue created in BBR_STARTUP in a single round: */ static const int bbr_drain_gain = BBR_UNIT * 1000 / 2885; /* The gain for deriving steady-state cwnd tolerates delayed/stretched ACKs: */ static const int bbr_cwnd_gain = BBR_UNIT * 2; /* The pacing_gain values for the PROBE_BW gain cycle, to discover/share bw: */ static const int bbr_pacing_gain[] = { BBR_UNIT * 5 / 4, /* probe for more available bw */ BBR_UNIT * 3 / 4, /* drain queue and/or yield bw to other flows */ BBR_UNIT, BBR_UNIT, BBR_UNIT, /* cruise at 1.0*bw to utilize pipe, */ BBR_UNIT, BBR_UNIT, BBR_UNIT /* without creating excess queue... */ }; /* Randomize the starting gain cycling phase over N phases: */ static const u32 bbr_cycle_rand = 7; /* Try to keep at least this many packets in flight, if things go smoothly. For * smooth functioning, a sliding window protocol ACKing every other packet * needs at least 4 packets in flight: */ static const u32 bbr_cwnd_min_target = 4; /* To estimate if BBR_STARTUP mode (i.e. high_gain) has filled pipe... */ /* If bw has increased significantly (1.25x), there may be more bw available: */ static const u32 bbr_full_bw_thresh = BBR_UNIT * 5 / 4; /* But after 3 rounds w/o significant bw growth, estimate pipe is full: */ static const u32 bbr_full_bw_cnt = 3; /* "long-term" ("LT") bandwidth estimator parameters... */ /* The minimum number of rounds in an LT bw sampling interval: */ static const u32 bbr_lt_intvl_min_rtts = 4; /* If lost/delivered ratio > 20%, interval is "lossy" and we may be policed: */ static const u32 bbr_lt_loss_thresh = 50; /* If 2 intervals have a bw ratio <= 1/8, their bw is "consistent": */ static const u32 bbr_lt_bw_ratio = BBR_UNIT / 8; /* If 2 intervals have a bw diff <= 4 Kbit/sec their bw is "consistent": */ static const u32 bbr_lt_bw_diff = 4000 / 8; /* If we estimate we're policed, use lt_bw for this many round trips: */ static const u32 bbr_lt_bw_max_rtts = 48; /* Gain factor for adding extra_acked to target cwnd: */ static const int bbr_extra_acked_gain = BBR_UNIT; /* Window length of extra_acked window. */ static const u32 bbr_extra_acked_win_rtts = 5; /* Max allowed val for ack_epoch_acked, after which sampling epoch is reset */ static const u32 bbr_ack_epoch_acked_reset_thresh = 1U << 20; /* Time period for clamping cwnd increment due to ack aggregation */ static const u32 bbr_extra_acked_max_us = 100 * 1000; static void bbr_check_probe_rtt_done(struct sock *sk); /* Do we estimate that STARTUP filled the pipe? */ static bool bbr_full_bw_reached(const struct sock *sk) { const struct bbr *bbr = inet_csk_ca(sk); return bbr->full_bw_reached; } /* Return the windowed max recent bandwidth sample, in pkts/uS << BW_SCALE. */ static u32 bbr_max_bw(const struct sock *sk) { struct bbr *bbr = inet_csk_ca(sk); return minmax_get(&bbr->bw); } /* Return the estimated bandwidth of the path, in pkts/uS << BW_SCALE. */ static u32 bbr_bw(const struct sock *sk) { struct bbr *bbr = inet_csk_ca(sk); return bbr->lt_use_bw ? bbr->lt_bw : bbr_max_bw(sk); } /* Return maximum extra acked in past k-2k round trips, * where k = bbr_extra_acked_win_rtts. */ static u16 bbr_extra_acked(const struct sock *sk) { struct bbr *bbr = inet_csk_ca(sk); return max(bbr->extra_acked[0], bbr->extra_acked[1]); } /* Return rate in bytes per second, optionally with a gain. * The order here is chosen carefully to avoid overflow of u64. This should * work for input rates of up to 2.9Tbit/sec and gain of 2.89x. */ static u64 bbr_rate_bytes_per_sec(struct sock *sk, u64 rate, int gain) { unsigned int mss = tcp_sk(sk)->mss_cache; rate *= mss; rate *= gain; rate >>= BBR_SCALE; rate *= USEC_PER_SEC / 100 * (100 - bbr_pacing_margin_percent); return rate >> BW_SCALE; } /* Convert a BBR bw and gain factor to a pacing rate in bytes per second. */ static unsigned long bbr_bw_to_pacing_rate(struct sock *sk, u32 bw, int gain) { u64 rate = bw; rate = bbr_rate_bytes_per_sec(sk, rate, gain); rate = min_t(u64, rate, sk->sk_max_pacing_rate); return rate; } /* Initialize pacing rate to: high_gain * init_cwnd / RTT. */ static void bbr_init_pacing_rate_from_rtt(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); u64 bw; u32 rtt_us; if (tp->srtt_us) { /* any RTT sample yet? */ rtt_us = max(tp->srtt_us >> 3, 1U); bbr->has_seen_rtt = 1; } else { /* no RTT sample yet */ rtt_us = USEC_PER_MSEC; /* use nominal default RTT */ } bw = (u64)tcp_snd_cwnd(tp) * BW_UNIT; do_div(bw, rtt_us); sk->sk_pacing_rate = bbr_bw_to_pacing_rate(sk, bw, bbr_high_gain); } /* Pace using current bw estimate and a gain factor. */ static void bbr_set_pacing_rate(struct sock *sk, u32 bw, int gain) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); unsigned long rate = bbr_bw_to_pacing_rate(sk, bw, gain); if (unlikely(!bbr->has_seen_rtt && tp->srtt_us)) bbr_init_pacing_rate_from_rtt(sk); if (bbr_full_bw_reached(sk) || rate > sk->sk_pacing_rate) sk->sk_pacing_rate = rate; } /* override sysctl_tcp_min_tso_segs */ __bpf_kfunc static u32 bbr_min_tso_segs(struct sock *sk) { return sk->sk_pacing_rate < (bbr_min_tso_rate >> 3) ? 1 : 2; } static u32 bbr_tso_segs_goal(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); u32 segs, bytes; /* Sort of tcp_tso_autosize() but ignoring * driver provided sk_gso_max_size. */ bytes = min_t(unsigned long, sk->sk_pacing_rate >> READ_ONCE(sk->sk_pacing_shift), GSO_LEGACY_MAX_SIZE - 1 - MAX_TCP_HEADER); segs = max_t(u32, bytes / tp->mss_cache, bbr_min_tso_segs(sk)); return min(segs, 0x7FU); } /* Save "last known good" cwnd so we can restore it after losses or PROBE_RTT */ static void bbr_save_cwnd(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); if (bbr->prev_ca_state < TCP_CA_Recovery && bbr->mode != BBR_PROBE_RTT) bbr->prior_cwnd = tcp_snd_cwnd(tp); /* this cwnd is good enough */ else /* loss recovery or BBR_PROBE_RTT have temporarily cut cwnd */ bbr->prior_cwnd = max(bbr->prior_cwnd, tcp_snd_cwnd(tp)); } __bpf_kfunc static void bbr_cwnd_event(struct sock *sk, enum tcp_ca_event event) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); if (event == CA_EVENT_TX_START && tp->app_limited) { bbr->idle_restart = 1; bbr->ack_epoch_mstamp = tp->tcp_mstamp; bbr->ack_epoch_acked = 0; /* Avoid pointless buffer overflows: pace at est. bw if we don't * need more speed (we're restarting from idle and app-limited). */ if (bbr->mode == BBR_PROBE_BW) bbr_set_pacing_rate(sk, bbr_bw(sk), BBR_UNIT); else if (bbr->mode == BBR_PROBE_RTT) bbr_check_probe_rtt_done(sk); } } /* Calculate bdp based on min RTT and the estimated bottleneck bandwidth: * * bdp = ceil(bw * min_rtt * gain) * * The key factor, gain, controls the amount of queue. While a small gain * builds a smaller queue, it becomes more vulnerable to noise in RTT * measurements (e.g., delayed ACKs or other ACK compression effects). This * noise may cause BBR to under-estimate the rate. */ static u32 bbr_bdp(struct sock *sk, u32 bw, int gain) { struct bbr *bbr = inet_csk_ca(sk); u32 bdp; u64 w; /* If we've never had a valid RTT sample, cap cwnd at the initial * default. This should only happen when the connection is not using TCP * timestamps and has retransmitted all of the SYN/SYNACK/data packets * ACKed so far. In this case, an RTO can cut cwnd to 1, in which * case we need to slow-start up toward something safe: TCP_INIT_CWND. */ if (unlikely(bbr->min_rtt_us == ~0U)) /* no valid RTT samples yet? */ return TCP_INIT_CWND; /* be safe: cap at default initial cwnd*/ w = (u64)bw * bbr->min_rtt_us; /* Apply a gain to the given value, remove the BW_SCALE shift, and * round the value up to avoid a negative feedback loop. */ bdp = (((w * gain) >> BBR_SCALE) + BW_UNIT - 1) / BW_UNIT; return bdp; } /* To achieve full performance in high-speed paths, we budget enough cwnd to * fit full-sized skbs in-flight on both end hosts to fully utilize the path: * - one skb in sending host Qdisc, * - one skb in sending host TSO/GSO engine * - one skb being received by receiver host LRO/GRO/delayed-ACK engine * Don't worry, at low rates (bbr_min_tso_rate) this won't bloat cwnd because * in such cases tso_segs_goal is 1. The minimum cwnd is 4 packets, * which allows 2 outstanding 2-packet sequences, to try to keep pipe * full even with ACK-every-other-packet delayed ACKs. */ static u32 bbr_quantization_budget(struct sock *sk, u32 cwnd) { struct bbr *bbr = inet_csk_ca(sk); /* Allow enough full-sized skbs in flight to utilize end systems. */ cwnd += 3 * bbr_tso_segs_goal(sk); /* Reduce delayed ACKs by rounding up cwnd to the next even number. */ cwnd = (cwnd + 1) & ~1U; /* Ensure gain cycling gets inflight above BDP even for small BDPs. */ if (bbr->mode == BBR_PROBE_BW && bbr->cycle_idx == 0) cwnd += 2; return cwnd; } /* Find inflight based on min RTT and the estimated bottleneck bandwidth. */ static u32 bbr_inflight(struct sock *sk, u32 bw, int gain) { u32 inflight; inflight = bbr_bdp(sk, bw, gain); inflight = bbr_quantization_budget(sk, inflight); return inflight; } /* With pacing at lower layers, there's often less data "in the network" than * "in flight". With TSQ and departure time pacing at lower layers (e.g. fq), * we often have several skbs queued in the pacing layer with a pre-scheduled * earliest departure time (EDT). BBR adapts its pacing rate based on the * inflight level that it estimates has already been "baked in" by previous * departure time decisions. We calculate a rough estimate of the number of our * packets that might be in the network at the earliest departure time for the * next skb scheduled: * in_network_at_edt = inflight_at_edt - (EDT - now) * bw * If we're increasing inflight, then we want to know if the transmit of the * EDT skb will push inflight above the target, so inflight_at_edt includes * bbr_tso_segs_goal() from the skb departing at EDT. If decreasing inflight, * then estimate if inflight will sink too low just before the EDT transmit. */ static u32 bbr_packets_in_net_at_edt(struct sock *sk, u32 inflight_now) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); u64 now_ns, edt_ns, interval_us; u32 interval_delivered, inflight_at_edt; now_ns = tp->tcp_clock_cache; edt_ns = max(tp->tcp_wstamp_ns, now_ns); interval_us = div_u64(edt_ns - now_ns, NSEC_PER_USEC); interval_delivered = (u64)bbr_bw(sk) * interval_us >> BW_SCALE; inflight_at_edt = inflight_now; if (bbr->pacing_gain > BBR_UNIT) /* increasing inflight */ inflight_at_edt += bbr_tso_segs_goal(sk); /* include EDT skb */ if (interval_delivered >= inflight_at_edt) return 0; return inflight_at_edt - interval_delivered; } /* Find the cwnd increment based on estimate of ack aggregation */ static u32 bbr_ack_aggregation_cwnd(struct sock *sk) { u32 max_aggr_cwnd, aggr_cwnd = 0; if (bbr_extra_acked_gain && bbr_full_bw_reached(sk)) { max_aggr_cwnd = ((u64)bbr_bw(sk) * bbr_extra_acked_max_us) / BW_UNIT; aggr_cwnd = (bbr_extra_acked_gain * bbr_extra_acked(sk)) >> BBR_SCALE; aggr_cwnd = min(aggr_cwnd, max_aggr_cwnd); } return aggr_cwnd; } /* An optimization in BBR to reduce losses: On the first round of recovery, we * follow the packet conservation principle: send P packets per P packets acked. * After that, we slow-start and send at most 2*P packets per P packets acked. * After recovery finishes, or upon undo, we restore the cwnd we had when * recovery started (capped by the target cwnd based on estimated BDP). * * TODO(ycheng/ncardwell): implement a rate-based approach. */ static bool bbr_set_cwnd_to_recover_or_restore( struct sock *sk, const struct rate_sample *rs, u32 acked, u32 *new_cwnd) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); u8 prev_state = bbr->prev_ca_state, state = inet_csk(sk)->icsk_ca_state; u32 cwnd = tcp_snd_cwnd(tp); /* An ACK for P pkts should release at most 2*P packets. We do this * in two steps. First, here we deduct the number of lost packets. * Then, in bbr_set_cwnd() we slow start up toward the target cwnd. */ if (rs->losses > 0) cwnd = max_t(s32, cwnd - rs->losses, 1); if (state == TCP_CA_Recovery && prev_state != TCP_CA_Recovery) { /* Starting 1st round of Recovery, so do packet conservation. */ bbr->packet_conservation = 1; bbr->next_rtt_delivered = tp->delivered; /* start round now */ /* Cut unused cwnd from app behavior, TSQ, or TSO deferral: */ cwnd = tcp_packets_in_flight(tp) + acked; } else if (prev_state >= TCP_CA_Recovery && state < TCP_CA_Recovery) { /* Exiting loss recovery; restore cwnd saved before recovery. */ cwnd = max(cwnd, bbr->prior_cwnd); bbr->packet_conservation = 0; } bbr->prev_ca_state = state; if (bbr->packet_conservation) { *new_cwnd = max(cwnd, tcp_packets_in_flight(tp) + acked); return true; /* yes, using packet conservation */ } *new_cwnd = cwnd; return false; } /* Slow-start up toward target cwnd (if bw estimate is growing, or packet loss * has drawn us down below target), or snap down to target if we're above it. */ static void bbr_set_cwnd(struct sock *sk, const struct rate_sample *rs, u32 acked, u32 bw, int gain) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); u32 cwnd = tcp_snd_cwnd(tp), target_cwnd = 0; if (!acked) goto done; /* no packet fully ACKed; just apply caps */ if (bbr_set_cwnd_to_recover_or_restore(sk, rs, acked, &cwnd)) goto done; target_cwnd = bbr_bdp(sk, bw, gain); /* Increment the cwnd to account for excess ACKed data that seems * due to aggregation (of data and/or ACKs) visible in the ACK stream. */ target_cwnd += bbr_ack_aggregation_cwnd(sk); target_cwnd = bbr_quantization_budget(sk, target_cwnd); /* If we're below target cwnd, slow start cwnd toward target cwnd. */ if (bbr_full_bw_reached(sk)) /* only cut cwnd if we filled the pipe */ cwnd = min(cwnd + acked, target_cwnd); else if (cwnd < target_cwnd || tp->delivered < TCP_INIT_CWND) cwnd = cwnd + acked; cwnd = max(cwnd, bbr_cwnd_min_target); done: tcp_snd_cwnd_set(tp, min(cwnd, tp->snd_cwnd_clamp)); /* apply global cap */ if (bbr->mode == BBR_PROBE_RTT) /* drain queue, refresh min_rtt */ tcp_snd_cwnd_set(tp, min(tcp_snd_cwnd(tp), bbr_cwnd_min_target)); } /* End cycle phase if it's time and/or we hit the phase's in-flight target. */ static bool bbr_is_next_cycle_phase(struct sock *sk, const struct rate_sample *rs) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); bool is_full_length = tcp_stamp_us_delta(tp->delivered_mstamp, bbr->cycle_mstamp) > bbr->min_rtt_us; u32 inflight, bw; /* The pacing_gain of 1.0 paces at the estimated bw to try to fully * use the pipe without increasing the queue. */ if (bbr->pacing_gain == BBR_UNIT) return is_full_length; /* just use wall clock time */ inflight = bbr_packets_in_net_at_edt(sk, rs->prior_in_flight); bw = bbr_max_bw(sk); /* A pacing_gain > 1.0 probes for bw by trying to raise inflight to at * least pacing_gain*BDP; this may take more than min_rtt if min_rtt is * small (e.g. on a LAN). We do not persist if packets are lost, since * a path with small buffers may not hold that much. */ if (bbr->pacing_gain > BBR_UNIT) return is_full_length && (rs->losses || /* perhaps pacing_gain*BDP won't fit */ inflight >= bbr_inflight(sk, bw, bbr->pacing_gain)); /* A pacing_gain < 1.0 tries to drain extra queue we added if bw * probing didn't find more bw. If inflight falls to match BDP then we * estimate queue is drained; persisting would underutilize the pipe. */ return is_full_length || inflight <= bbr_inflight(sk, bw, BBR_UNIT); } static void bbr_advance_cycle_phase(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); bbr->cycle_idx = (bbr->cycle_idx + 1) & (CYCLE_LEN - 1); bbr->cycle_mstamp = tp->delivered_mstamp; } /* Gain cycling: cycle pacing gain to converge to fair share of available bw. */ static void bbr_update_cycle_phase(struct sock *sk, const struct rate_sample *rs) { struct bbr *bbr = inet_csk_ca(sk); if (bbr->mode == BBR_PROBE_BW && bbr_is_next_cycle_phase(sk, rs)) bbr_advance_cycle_phase(sk); } static void bbr_reset_startup_mode(struct sock *sk) { struct bbr *bbr = inet_csk_ca(sk); bbr->mode = BBR_STARTUP; } static void bbr_reset_probe_bw_mode(struct sock *sk) { struct bbr *bbr = inet_csk_ca(sk); bbr->mode = BBR_PROBE_BW; bbr->cycle_idx = CYCLE_LEN - 1 - get_random_u32_below(bbr_cycle_rand); bbr_advance_cycle_phase(sk); /* flip to next phase of gain cycle */ } static void bbr_reset_mode(struct sock *sk) { if (!bbr_full_bw_reached(sk)) bbr_reset_startup_mode(sk); else bbr_reset_probe_bw_mode(sk); } /* Start a new long-term sampling interval. */ static void bbr_reset_lt_bw_sampling_interval(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); bbr->lt_last_stamp = div_u64(tp->delivered_mstamp, USEC_PER_MSEC); bbr->lt_last_delivered = tp->delivered; bbr->lt_last_lost = tp->lost; bbr->lt_rtt_cnt = 0; } /* Completely reset long-term bandwidth sampling. */ static void bbr_reset_lt_bw_sampling(struct sock *sk) { struct bbr *bbr = inet_csk_ca(sk); bbr->lt_bw = 0; bbr->lt_use_bw = 0; bbr->lt_is_sampling = false; bbr_reset_lt_bw_sampling_interval(sk); } /* Long-term bw sampling interval is done. Estimate whether we're policed. */ static void bbr_lt_bw_interval_done(struct sock *sk, u32 bw) { struct bbr *bbr = inet_csk_ca(sk); u32 diff; if (bbr->lt_bw) { /* do we have bw from a previous interval? */ /* Is new bw close to the lt_bw from the previous interval? */ diff = abs(bw - bbr->lt_bw); if ((diff * BBR_UNIT <= bbr_lt_bw_ratio * bbr->lt_bw) || (bbr_rate_bytes_per_sec(sk, diff, BBR_UNIT) <= bbr_lt_bw_diff)) { /* All criteria are met; estimate we're policed. */ bbr->lt_bw = (bw + bbr->lt_bw) >> 1; /* avg 2 intvls */ bbr->lt_use_bw = 1; bbr->pacing_gain = BBR_UNIT; /* try to avoid drops */ bbr->lt_rtt_cnt = 0; return; } } bbr->lt_bw = bw; bbr_reset_lt_bw_sampling_interval(sk); } /* Token-bucket traffic policers are common (see "An Internet-Wide Analysis of * Traffic Policing", SIGCOMM 2016). BBR detects token-bucket policers and * explicitly models their policed rate, to reduce unnecessary losses. We * estimate that we're policed if we see 2 consecutive sampling intervals with * consistent throughput and high packet loss. If we think we're being policed, * set lt_bw to the "long-term" average delivery rate from those 2 intervals. */ static void bbr_lt_bw_sampling(struct sock *sk, const struct rate_sample *rs) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); u32 lost, delivered; u64 bw; u32 t; if (bbr->lt_use_bw) { /* already using long-term rate, lt_bw? */ if (bbr->mode == BBR_PROBE_BW && bbr->round_start && ++bbr->lt_rtt_cnt >= bbr_lt_bw_max_rtts) { bbr_reset_lt_bw_sampling(sk); /* stop using lt_bw */ bbr_reset_probe_bw_mode(sk); /* restart gain cycling */ } return; } /* Wait for the first loss before sampling, to let the policer exhaust * its tokens and estimate the steady-state rate allowed by the policer. * Starting samples earlier includes bursts that over-estimate the bw. */ if (!bbr->lt_is_sampling) { if (!rs->losses) return; bbr_reset_lt_bw_sampling_interval(sk); bbr->lt_is_sampling = true; } /* To avoid underestimates, reset sampling if we run out of data. */ if (rs->is_app_limited) { bbr_reset_lt_bw_sampling(sk); return; } if (bbr->round_start) bbr->lt_rtt_cnt++; /* count round trips in this interval */ if (bbr->lt_rtt_cnt < bbr_lt_intvl_min_rtts) return; /* sampling interval needs to be longer */ if (bbr->lt_rtt_cnt > 4 * bbr_lt_intvl_min_rtts) { bbr_reset_lt_bw_sampling(sk); /* interval is too long */ return; } /* End sampling interval when a packet is lost, so we estimate the * policer tokens were exhausted. Stopping the sampling before the * tokens are exhausted under-estimates the policed rate. */ if (!rs->losses) return; /* Calculate packets lost and delivered in sampling interval. */ lost = tp->lost - bbr->lt_last_lost; delivered = tp->delivered - bbr->lt_last_delivered; /* Is loss rate (lost/delivered) >= lt_loss_thresh? If not, wait. */ if (!delivered || (lost << BBR_SCALE) < bbr_lt_loss_thresh * delivered) return; /* Find average delivery rate in this sampling interval. */ t = div_u64(tp->delivered_mstamp, USEC_PER_MSEC) - bbr->lt_last_stamp; if ((s32)t < 1) return; /* interval is less than one ms, so wait */ /* Check if can multiply without overflow */ if (t >= ~0U / USEC_PER_MSEC) { bbr_reset_lt_bw_sampling(sk); /* interval too long; reset */ return; } t *= USEC_PER_MSEC; bw = (u64)delivered * BW_UNIT; do_div(bw, t); bbr_lt_bw_interval_done(sk, bw); } /* Estimate the bandwidth based on how fast packets are delivered */ static void bbr_update_bw(struct sock *sk, const struct rate_sample *rs) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); u64 bw; bbr->round_start = 0; if (rs->delivered < 0 || rs->interval_us <= 0) return; /* Not a valid observation */ /* See if we've reached the next RTT */ if (!before(rs->prior_delivered, bbr->next_rtt_delivered)) { bbr->next_rtt_delivered = tp->delivered; bbr->rtt_cnt++; bbr->round_start = 1; bbr->packet_conservation = 0; } bbr_lt_bw_sampling(sk, rs); /* Divide delivered by the interval to find a (lower bound) bottleneck * bandwidth sample. Delivered is in packets and interval_us in uS and * ratio will be <<1 for most connections. So delivered is first scaled. */ bw = div64_long((u64)rs->delivered * BW_UNIT, rs->interval_us); /* If this sample is application-limited, it is likely to have a very * low delivered count that represents application behavior rather than * the available network rate. Such a sample could drag down estimated * bw, causing needless slow-down. Thus, to continue to send at the * last measured network rate, we filter out app-limited samples unless * they describe the path bw at least as well as our bw model. * * So the goal during app-limited phase is to proceed with the best * network rate no matter how long. We automatically leave this * phase when app writes faster than the network can deliver :) */ if (!rs->is_app_limited || bw >= bbr_max_bw(sk)) { /* Incorporate new sample into our max bw filter. */ minmax_running_max(&bbr->bw, bbr_bw_rtts, bbr->rtt_cnt, bw); } } /* Estimates the windowed max degree of ack aggregation. * This is used to provision extra in-flight data to keep sending during * inter-ACK silences. * * Degree of ack aggregation is estimated as extra data acked beyond expected. * * max_extra_acked = "maximum recent excess data ACKed beyond max_bw * interval" * cwnd += max_extra_acked * * Max extra_acked is clamped by cwnd and bw * bbr_extra_acked_max_us (100 ms). * Max filter is an approximate sliding window of 5-10 (packet timed) round * trips. */ static void bbr_update_ack_aggregation(struct sock *sk, const struct rate_sample *rs) { u32 epoch_us, expected_acked, extra_acked; struct bbr *bbr = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); if (!bbr_extra_acked_gain || rs->acked_sacked <= 0 || rs->delivered < 0 || rs->interval_us <= 0) return; if (bbr->round_start) { bbr->extra_acked_win_rtts = min(0x1F, bbr->extra_acked_win_rtts + 1); if (bbr->extra_acked_win_rtts >= bbr_extra_acked_win_rtts) { bbr->extra_acked_win_rtts = 0; bbr->extra_acked_win_idx = bbr->extra_acked_win_idx ? 0 : 1; bbr->extra_acked[bbr->extra_acked_win_idx] = 0; } } /* Compute how many packets we expected to be delivered over epoch. */ epoch_us = tcp_stamp_us_delta(tp->delivered_mstamp, bbr->ack_epoch_mstamp); expected_acked = ((u64)bbr_bw(sk) * epoch_us) / BW_UNIT; /* Reset the aggregation epoch if ACK rate is below expected rate or * significantly large no. of ack received since epoch (potentially * quite old epoch). */ if (bbr->ack_epoch_acked <= expected_acked || (bbr->ack_epoch_acked + rs->acked_sacked >= bbr_ack_epoch_acked_reset_thresh)) { bbr->ack_epoch_acked = 0; bbr->ack_epoch_mstamp = tp->delivered_mstamp; expected_acked = 0; } /* Compute excess data delivered, beyond what was expected. */ bbr->ack_epoch_acked = min_t(u32, 0xFFFFF, bbr->ack_epoch_acked + rs->acked_sacked); extra_acked = bbr->ack_epoch_acked - expected_acked; extra_acked = min(extra_acked, tcp_snd_cwnd(tp)); if (extra_acked > bbr->extra_acked[bbr->extra_acked_win_idx]) bbr->extra_acked[bbr->extra_acked_win_idx] = extra_acked; } /* Estimate when the pipe is full, using the change in delivery rate: BBR * estimates that STARTUP filled the pipe if the estimated bw hasn't changed by * at least bbr_full_bw_thresh (25%) after bbr_full_bw_cnt (3) non-app-limited * rounds. Why 3 rounds: 1: rwin autotuning grows the rwin, 2: we fill the * higher rwin, 3: we get higher delivery rate samples. Or transient * cross-traffic or radio noise can go away. CUBIC Hystart shares a similar * design goal, but uses delay and inter-ACK spacing instead of bandwidth. */ static void bbr_check_full_bw_reached(struct sock *sk, const struct rate_sample *rs) { struct bbr *bbr = inet_csk_ca(sk); u32 bw_thresh; if (bbr_full_bw_reached(sk) || !bbr->round_start || rs->is_app_limited) return; bw_thresh = (u64)bbr->full_bw * bbr_full_bw_thresh >> BBR_SCALE; if (bbr_max_bw(sk) >= bw_thresh) { bbr->full_bw = bbr_max_bw(sk); bbr->full_bw_cnt = 0; return; } ++bbr->full_bw_cnt; bbr->full_bw_reached = bbr->full_bw_cnt >= bbr_full_bw_cnt; } /* If pipe is probably full, drain the queue and then enter steady-state. */ static void bbr_check_drain(struct sock *sk, const struct rate_sample *rs) { struct bbr *bbr = inet_csk_ca(sk); if (bbr->mode == BBR_STARTUP && bbr_full_bw_reached(sk)) { bbr->mode = BBR_DRAIN; /* drain queue we created */ tcp_sk(sk)->snd_ssthresh = bbr_inflight(sk, bbr_max_bw(sk), BBR_UNIT); } /* fall through to check if in-flight is already small: */ if (bbr->mode == BBR_DRAIN && bbr_packets_in_net_at_edt(sk, tcp_packets_in_flight(tcp_sk(sk))) <= bbr_inflight(sk, bbr_max_bw(sk), BBR_UNIT)) bbr_reset_probe_bw_mode(sk); /* we estimate queue is drained */ } static void bbr_check_probe_rtt_done(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); if (!(bbr->probe_rtt_done_stamp && after(tcp_jiffies32, bbr->probe_rtt_done_stamp))) return; bbr->min_rtt_stamp = tcp_jiffies32; /* wait a while until PROBE_RTT */ tcp_snd_cwnd_set(tp, max(tcp_snd_cwnd(tp), bbr->prior_cwnd)); bbr_reset_mode(sk); } /* The goal of PROBE_RTT mode is to have BBR flows cooperatively and * periodically drain the bottleneck queue, to converge to measure the true * min_rtt (unloaded propagation delay). This allows the flows to keep queues * small (reducing queuing delay and packet loss) and achieve fairness among * BBR flows. * * The min_rtt filter window is 10 seconds. When the min_rtt estimate expires, * we enter PROBE_RTT mode and cap the cwnd at bbr_cwnd_min_target=4 packets. * After at least bbr_probe_rtt_mode_ms=200ms and at least one packet-timed * round trip elapsed with that flight size <= 4, we leave PROBE_RTT mode and * re-enter the previous mode. BBR uses 200ms to approximately bound the * performance penalty of PROBE_RTT's cwnd capping to roughly 2% (200ms/10s). * * Note that flows need only pay 2% if they are busy sending over the last 10 * seconds. Interactive applications (e.g., Web, RPCs, video chunks) often have * natural silences or low-rate periods within 10 seconds where the rate is low * enough for long enough to drain its queue in the bottleneck. We pick up * these min RTT measurements opportunistically with our min_rtt filter. :-) */ static void bbr_update_min_rtt(struct sock *sk, const struct rate_sample *rs) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); bool filter_expired; /* Track min RTT seen in the min_rtt_win_sec filter window: */ filter_expired = after(tcp_jiffies32, bbr->min_rtt_stamp + bbr_min_rtt_win_sec * HZ); if (rs->rtt_us >= 0 && (rs->rtt_us < bbr->min_rtt_us || (filter_expired && !rs->is_ack_delayed))) { bbr->min_rtt_us = rs->rtt_us; bbr->min_rtt_stamp = tcp_jiffies32; } if (bbr_probe_rtt_mode_ms > 0 && filter_expired && !bbr->idle_restart && bbr->mode != BBR_PROBE_RTT) { bbr->mode = BBR_PROBE_RTT; /* dip, drain queue */ bbr_save_cwnd(sk); /* note cwnd so we can restore it */ bbr->probe_rtt_done_stamp = 0; } if (bbr->mode == BBR_PROBE_RTT) { /* Ignore low rate samples during this mode. */ tp->app_limited = (tp->delivered + tcp_packets_in_flight(tp)) ? : 1; /* Maintain min packets in flight for max(200 ms, 1 round). */ if (!bbr->probe_rtt_done_stamp && tcp_packets_in_flight(tp) <= bbr_cwnd_min_target) { bbr->probe_rtt_done_stamp = tcp_jiffies32 + msecs_to_jiffies(bbr_probe_rtt_mode_ms); bbr->probe_rtt_round_done = 0; bbr->next_rtt_delivered = tp->delivered; } else if (bbr->probe_rtt_done_stamp) { if (bbr->round_start) bbr->probe_rtt_round_done = 1; if (bbr->probe_rtt_round_done) bbr_check_probe_rtt_done(sk); } } /* Restart after idle ends only once we process a new S/ACK for data */ if (rs->delivered > 0) bbr->idle_restart = 0; } static void bbr_update_gains(struct sock *sk) { struct bbr *bbr = inet_csk_ca(sk); switch (bbr->mode) { case BBR_STARTUP: bbr->pacing_gain = bbr_high_gain; bbr->cwnd_gain = bbr_high_gain; break; case BBR_DRAIN: bbr->pacing_gain = bbr_drain_gain; /* slow, to drain */ bbr->cwnd_gain = bbr_high_gain; /* keep cwnd */ break; case BBR_PROBE_BW: bbr->pacing_gain = (bbr->lt_use_bw ? BBR_UNIT : bbr_pacing_gain[bbr->cycle_idx]); bbr->cwnd_gain = bbr_cwnd_gain; break; case BBR_PROBE_RTT: bbr->pacing_gain = BBR_UNIT; bbr->cwnd_gain = BBR_UNIT; break; default: WARN_ONCE(1, "BBR bad mode: %u\n", bbr->mode); break; } } static void bbr_update_model(struct sock *sk, const struct rate_sample *rs) { bbr_update_bw(sk, rs); bbr_update_ack_aggregation(sk, rs); bbr_update_cycle_phase(sk, rs); bbr_check_full_bw_reached(sk, rs); bbr_check_drain(sk, rs); bbr_update_min_rtt(sk, rs); bbr_update_gains(sk); } __bpf_kfunc static void bbr_main(struct sock *sk, const struct rate_sample *rs) { struct bbr *bbr = inet_csk_ca(sk); u32 bw; bbr_update_model(sk, rs); bw = bbr_bw(sk); bbr_set_pacing_rate(sk, bw, bbr->pacing_gain); bbr_set_cwnd(sk, rs, rs->acked_sacked, bw, bbr->cwnd_gain); } __bpf_kfunc static void bbr_init(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); bbr->prior_cwnd = 0; tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; bbr->rtt_cnt = 0; bbr->next_rtt_delivered = tp->delivered; bbr->prev_ca_state = TCP_CA_Open; bbr->packet_conservation = 0; bbr->probe_rtt_done_stamp = 0; bbr->probe_rtt_round_done = 0; bbr->min_rtt_us = tcp_min_rtt(tp); bbr->min_rtt_stamp = tcp_jiffies32; minmax_reset(&bbr->bw, bbr->rtt_cnt, 0); /* init max bw to 0 */ bbr->has_seen_rtt = 0; bbr_init_pacing_rate_from_rtt(sk); bbr->round_start = 0; bbr->idle_restart = 0; bbr->full_bw_reached = 0; bbr->full_bw = 0; bbr->full_bw_cnt = 0; bbr->cycle_mstamp = 0; bbr->cycle_idx = 0; bbr_reset_lt_bw_sampling(sk); bbr_reset_startup_mode(sk); bbr->ack_epoch_mstamp = tp->tcp_mstamp; bbr->ack_epoch_acked = 0; bbr->extra_acked_win_rtts = 0; bbr->extra_acked_win_idx = 0; bbr->extra_acked[0] = 0; bbr->extra_acked[1] = 0; cmpxchg(&sk->sk_pacing_status, SK_PACING_NONE, SK_PACING_NEEDED); } __bpf_kfunc static u32 bbr_sndbuf_expand(struct sock *sk) { /* Provision 3 * cwnd since BBR may slow-start even during recovery. */ return 3; } /* In theory BBR does not need to undo the cwnd since it does not * always reduce cwnd on losses (see bbr_main()). Keep it for now. */ __bpf_kfunc static u32 bbr_undo_cwnd(struct sock *sk) { struct bbr *bbr = inet_csk_ca(sk); bbr->full_bw = 0; /* spurious slow-down; reset full pipe detection */ bbr->full_bw_cnt = 0; bbr_reset_lt_bw_sampling(sk); return tcp_snd_cwnd(tcp_sk(sk)); } /* Entering loss recovery, so save cwnd for when we exit or undo recovery. */ __bpf_kfunc static u32 bbr_ssthresh(struct sock *sk) { bbr_save_cwnd(sk); return tcp_sk(sk)->snd_ssthresh; } static size_t bbr_get_info(struct sock *sk, u32 ext, int *attr, union tcp_cc_info *info) { if (ext & (1 << (INET_DIAG_BBRINFO - 1)) || ext & (1 << (INET_DIAG_VEGASINFO - 1))) { struct tcp_sock *tp = tcp_sk(sk); struct bbr *bbr = inet_csk_ca(sk); u64 bw = bbr_bw(sk); bw = bw * tp->mss_cache * USEC_PER_SEC >> BW_SCALE; memset(&info->bbr, 0, sizeof(info->bbr)); info->bbr.bbr_bw_lo = (u32)bw; info->bbr.bbr_bw_hi = (u32)(bw >> 32); info->bbr.bbr_min_rtt = bbr->min_rtt_us; info->bbr.bbr_pacing_gain = bbr->pacing_gain; info->bbr.bbr_cwnd_gain = bbr->cwnd_gain; *attr = INET_DIAG_BBRINFO; return sizeof(info->bbr); } return 0; } __bpf_kfunc static void bbr_set_state(struct sock *sk, u8 new_state) { struct bbr *bbr = inet_csk_ca(sk); if (new_state == TCP_CA_Loss) { struct rate_sample rs = { .losses = 1 }; bbr->prev_ca_state = TCP_CA_Loss; bbr->full_bw = 0; bbr->round_start = 1; /* treat RTO like end of a round */ bbr_lt_bw_sampling(sk, &rs); } } static struct tcp_congestion_ops tcp_bbr_cong_ops __read_mostly = { .flags = TCP_CONG_NON_RESTRICTED, .name = "bbr", .owner = THIS_MODULE, .init = bbr_init, .cong_control = bbr_main, .sndbuf_expand = bbr_sndbuf_expand, .undo_cwnd = bbr_undo_cwnd, .cwnd_event = bbr_cwnd_event, .ssthresh = bbr_ssthresh, .min_tso_segs = bbr_min_tso_segs, .get_info = bbr_get_info, .set_state = bbr_set_state, }; BTF_SET8_START(tcp_bbr_check_kfunc_ids) #ifdef CONFIG_X86 #ifdef CONFIG_DYNAMIC_FTRACE BTF_ID_FLAGS(func, bbr_init) BTF_ID_FLAGS(func, bbr_main) BTF_ID_FLAGS(func, bbr_sndbuf_expand) BTF_ID_FLAGS(func, bbr_undo_cwnd) BTF_ID_FLAGS(func, bbr_cwnd_event) BTF_ID_FLAGS(func, bbr_ssthresh) BTF_ID_FLAGS(func, bbr_min_tso_segs) BTF_ID_FLAGS(func, bbr_set_state) #endif #endif BTF_SET8_END(tcp_bbr_check_kfunc_ids) static const struct btf_kfunc_id_set tcp_bbr_kfunc_set = { .owner = THIS_MODULE, .set = &tcp_bbr_check_kfunc_ids, }; static int __init bbr_register(void) { int ret; BUILD_BUG_ON(sizeof(struct bbr) > ICSK_CA_PRIV_SIZE); ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS, &tcp_bbr_kfunc_set); if (ret < 0) return ret; return tcp_register_congestion_control(&tcp_bbr_cong_ops); } static void __exit bbr_unregister(void) { tcp_unregister_congestion_control(&tcp_bbr_cong_ops); } module_init(bbr_register); module_exit(bbr_unregister); MODULE_AUTHOR("Van Jacobson <[email protected]>"); MODULE_AUTHOR("Neal Cardwell <[email protected]>"); MODULE_AUTHOR("Yuchung Cheng <[email protected]>"); MODULE_AUTHOR("Soheil Hassas Yeganeh <[email protected]>"); MODULE_LICENSE("Dual BSD/GPL"); MODULE_DESCRIPTION("TCP BBR (Bottleneck Bandwidth and RTT)");
linux-master
net/ipv4/tcp_bbr.c
// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2020 Cloudflare Ltd https://cloudflare.com */ #include <linux/skmsg.h> #include <net/sock.h> #include <net/udp.h> #include <net/inet_common.h> #include "udp_impl.h" static struct proto *udpv6_prot_saved __read_mostly; static int sk_udp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { #if IS_ENABLED(CONFIG_IPV6) if (sk->sk_family == AF_INET6) return udpv6_prot_saved->recvmsg(sk, msg, len, flags, addr_len); #endif return udp_prot.recvmsg(sk, msg, len, flags, addr_len); } static bool udp_sk_has_data(struct sock *sk) { return !skb_queue_empty(&udp_sk(sk)->reader_queue) || !skb_queue_empty(&sk->sk_receive_queue); } static bool psock_has_data(struct sk_psock *psock) { return !skb_queue_empty(&psock->ingress_skb) || !sk_psock_queue_empty(psock); } #define udp_msg_has_data(__sk, __psock) \ ({ udp_sk_has_data(__sk) || psock_has_data(__psock); }) static int udp_msg_wait_data(struct sock *sk, struct sk_psock *psock, long timeo) { DEFINE_WAIT_FUNC(wait, woken_wake_function); int ret = 0; if (sk->sk_shutdown & RCV_SHUTDOWN) return 1; if (!timeo) return ret; add_wait_queue(sk_sleep(sk), &wait); sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); ret = udp_msg_has_data(sk, psock); if (!ret) { wait_woken(&wait, TASK_INTERRUPTIBLE, timeo); ret = udp_msg_has_data(sk, psock); } sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); remove_wait_queue(sk_sleep(sk), &wait); return ret; } static int udp_bpf_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { struct sk_psock *psock; int copied, ret; if (unlikely(flags & MSG_ERRQUEUE)) return inet_recv_error(sk, msg, len, addr_len); if (!len) return 0; psock = sk_psock_get(sk); if (unlikely(!psock)) return sk_udp_recvmsg(sk, msg, len, flags, addr_len); if (!psock_has_data(psock)) { ret = sk_udp_recvmsg(sk, msg, len, flags, addr_len); goto out; } msg_bytes_ready: copied = sk_msg_recvmsg(sk, psock, msg, len, flags); if (!copied) { long timeo; int data; timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); data = udp_msg_wait_data(sk, psock, timeo); if (data) { if (psock_has_data(psock)) goto msg_bytes_ready; ret = sk_udp_recvmsg(sk, msg, len, flags, addr_len); goto out; } copied = -EAGAIN; } ret = copied; out: sk_psock_put(sk, psock); return ret; } enum { UDP_BPF_IPV4, UDP_BPF_IPV6, UDP_BPF_NUM_PROTS, }; static DEFINE_SPINLOCK(udpv6_prot_lock); static struct proto udp_bpf_prots[UDP_BPF_NUM_PROTS]; static void udp_bpf_rebuild_protos(struct proto *prot, const struct proto *base) { *prot = *base; prot->close = sock_map_close; prot->recvmsg = udp_bpf_recvmsg; prot->sock_is_readable = sk_msg_is_readable; } static void udp_bpf_check_v6_needs_rebuild(struct proto *ops) { if (unlikely(ops != smp_load_acquire(&udpv6_prot_saved))) { spin_lock_bh(&udpv6_prot_lock); if (likely(ops != udpv6_prot_saved)) { udp_bpf_rebuild_protos(&udp_bpf_prots[UDP_BPF_IPV6], ops); smp_store_release(&udpv6_prot_saved, ops); } spin_unlock_bh(&udpv6_prot_lock); } } static int __init udp_bpf_v4_build_proto(void) { udp_bpf_rebuild_protos(&udp_bpf_prots[UDP_BPF_IPV4], &udp_prot); return 0; } late_initcall(udp_bpf_v4_build_proto); int udp_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore) { int family = sk->sk_family == AF_INET ? UDP_BPF_IPV4 : UDP_BPF_IPV6; if (restore) { sk->sk_write_space = psock->saved_write_space; sock_replace_proto(sk, psock->sk_proto); return 0; } if (sk->sk_family == AF_INET6) udp_bpf_check_v6_needs_rebuild(psock->sk_proto); sock_replace_proto(sk, &udp_bpf_prots[family]); return 0; } EXPORT_SYMBOL_GPL(udp_bpf_update_proto);
linux-master
net/ipv4/udp_bpf.c
// SPDX-License-Identifier: GPL-2.0-only /* Unstable Fou Helpers for TC-BPF hook * * These are called from SCHED_CLS BPF programs. Note that it is * allowed to break compatibility for these functions since the interface they * are exposed through to BPF programs is explicitly unstable. */ #include <linux/bpf.h> #include <linux/btf_ids.h> #include <net/dst_metadata.h> #include <net/fou.h> struct bpf_fou_encap { __be16 sport; __be16 dport; }; enum bpf_fou_encap_type { FOU_BPF_ENCAP_FOU, FOU_BPF_ENCAP_GUE, }; __diag_push(); __diag_ignore_all("-Wmissing-prototypes", "Global functions as their definitions will be in BTF"); /* bpf_skb_set_fou_encap - Set FOU encap parameters * * This function allows for using GUE or FOU encapsulation together with an * ipip device in collect-metadata mode. * * It is meant to be used in BPF tc-hooks and after a call to the * bpf_skb_set_tunnel_key helper, responsible for setting IP addresses. * * Parameters: * @skb_ctx Pointer to ctx (__sk_buff) in TC program. Cannot be NULL * @encap Pointer to a `struct bpf_fou_encap` storing UDP src and * dst ports. If sport is set to 0 the kernel will auto-assign a * port. This is similar to using `encap-sport auto`. * Cannot be NULL * @type Encapsulation type for the packet. Their definitions are * specified in `enum bpf_fou_encap_type` */ __bpf_kfunc int bpf_skb_set_fou_encap(struct __sk_buff *skb_ctx, struct bpf_fou_encap *encap, int type) { struct sk_buff *skb = (struct sk_buff *)skb_ctx; struct ip_tunnel_info *info = skb_tunnel_info(skb); if (unlikely(!encap)) return -EINVAL; if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) return -EINVAL; switch (type) { case FOU_BPF_ENCAP_FOU: info->encap.type = TUNNEL_ENCAP_FOU; break; case FOU_BPF_ENCAP_GUE: info->encap.type = TUNNEL_ENCAP_GUE; break; default: info->encap.type = TUNNEL_ENCAP_NONE; } if (info->key.tun_flags & TUNNEL_CSUM) info->encap.flags |= TUNNEL_ENCAP_FLAG_CSUM; info->encap.sport = encap->sport; info->encap.dport = encap->dport; return 0; } /* bpf_skb_get_fou_encap - Get FOU encap parameters * * This function allows for reading encap metadata from a packet received * on an ipip device in collect-metadata mode. * * Parameters: * @skb_ctx Pointer to ctx (__sk_buff) in TC program. Cannot be NULL * @encap Pointer to a struct bpf_fou_encap storing UDP source and * destination port. Cannot be NULL */ __bpf_kfunc int bpf_skb_get_fou_encap(struct __sk_buff *skb_ctx, struct bpf_fou_encap *encap) { struct sk_buff *skb = (struct sk_buff *)skb_ctx; struct ip_tunnel_info *info = skb_tunnel_info(skb); if (unlikely(!info)) return -EINVAL; encap->sport = info->encap.sport; encap->dport = info->encap.dport; return 0; } __diag_pop() BTF_SET8_START(fou_kfunc_set) BTF_ID_FLAGS(func, bpf_skb_set_fou_encap) BTF_ID_FLAGS(func, bpf_skb_get_fou_encap) BTF_SET8_END(fou_kfunc_set) static const struct btf_kfunc_id_set fou_bpf_kfunc_set = { .owner = THIS_MODULE, .set = &fou_kfunc_set, }; int register_fou_bpf(void) { return register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &fou_bpf_kfunc_set); }
linux-master
net/ipv4/fou_bpf.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * NET3 IP device support routines. * * Derived from the IP parts of dev.c 1.0.19 * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * Mark Evans, <[email protected]> * * Additional Authors: * Alan Cox, <[email protected]> * Alexey Kuznetsov, <[email protected]> * * Changes: * Alexey Kuznetsov: pa_* fields are replaced with ifaddr * lists. * Cyrus Durgin: updated for kmod * Matthias Andree: in devinet_ioctl, compare label and * address (4.4BSD alias style support), * fall back to comparing just the label * if no match found. */ #include <linux/uaccess.h> #include <linux/bitops.h> #include <linux/capability.h> #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/sched/signal.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/in.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/if_addr.h> #include <linux/if_ether.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/skbuff.h> #include <linux/init.h> #include <linux/notifier.h> #include <linux/inetdevice.h> #include <linux/igmp.h> #include <linux/slab.h> #include <linux/hash.h> #ifdef CONFIG_SYSCTL #include <linux/sysctl.h> #endif #include <linux/kmod.h> #include <linux/netconf.h> #include <net/arp.h> #include <net/ip.h> #include <net/route.h> #include <net/ip_fib.h> #include <net/rtnetlink.h> #include <net/net_namespace.h> #include <net/addrconf.h> #define IPV6ONLY_FLAGS \ (IFA_F_NODAD | IFA_F_OPTIMISTIC | IFA_F_DADFAILED | \ IFA_F_HOMEADDRESS | IFA_F_TENTATIVE | \ IFA_F_MANAGETEMPADDR | IFA_F_STABLE_PRIVACY) static struct ipv4_devconf ipv4_devconf = { .data = { [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1, [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/, [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/, [IPV4_DEVCONF_ARP_EVICT_NOCARRIER - 1] = 1, }, }; static struct ipv4_devconf ipv4_devconf_dflt = { .data = { [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1, [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1, [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/, [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/, [IPV4_DEVCONF_ARP_EVICT_NOCARRIER - 1] = 1, }, }; #define IPV4_DEVCONF_DFLT(net, attr) \ IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr) static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = { [IFA_LOCAL] = { .type = NLA_U32 }, [IFA_ADDRESS] = { .type = NLA_U32 }, [IFA_BROADCAST] = { .type = NLA_U32 }, [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, [IFA_CACHEINFO] = { .len = sizeof(struct ifa_cacheinfo) }, [IFA_FLAGS] = { .type = NLA_U32 }, [IFA_RT_PRIORITY] = { .type = NLA_U32 }, [IFA_TARGET_NETNSID] = { .type = NLA_S32 }, [IFA_PROTO] = { .type = NLA_U8 }, }; struct inet_fill_args { u32 portid; u32 seq; int event; unsigned int flags; int netnsid; int ifindex; }; #define IN4_ADDR_HSIZE_SHIFT 8 #define IN4_ADDR_HSIZE (1U << IN4_ADDR_HSIZE_SHIFT) static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE]; static u32 inet_addr_hash(const struct net *net, __be32 addr) { u32 val = (__force u32) addr ^ net_hash_mix(net); return hash_32(val, IN4_ADDR_HSIZE_SHIFT); } static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa) { u32 hash = inet_addr_hash(net, ifa->ifa_local); ASSERT_RTNL(); hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]); } static void inet_hash_remove(struct in_ifaddr *ifa) { ASSERT_RTNL(); hlist_del_init_rcu(&ifa->hash); } /** * __ip_dev_find - find the first device with a given source address. * @net: the net namespace * @addr: the source address * @devref: if true, take a reference on the found device * * If a caller uses devref=false, it should be protected by RCU, or RTNL */ struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref) { struct net_device *result = NULL; struct in_ifaddr *ifa; rcu_read_lock(); ifa = inet_lookup_ifaddr_rcu(net, addr); if (!ifa) { struct flowi4 fl4 = { .daddr = addr }; struct fib_result res = { 0 }; struct fib_table *local; /* Fallback to FIB local table so that communication * over loopback subnets work. */ local = fib_get_table(net, RT_TABLE_LOCAL); if (local && !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) && res.type == RTN_LOCAL) result = FIB_RES_DEV(res); } else { result = ifa->ifa_dev->dev; } if (result && devref) dev_hold(result); rcu_read_unlock(); return result; } EXPORT_SYMBOL(__ip_dev_find); /* called under RCU lock */ struct in_ifaddr *inet_lookup_ifaddr_rcu(struct net *net, __be32 addr) { u32 hash = inet_addr_hash(net, addr); struct in_ifaddr *ifa; hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash) if (ifa->ifa_local == addr && net_eq(dev_net(ifa->ifa_dev->dev), net)) return ifa; return NULL; } static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32); static BLOCKING_NOTIFIER_HEAD(inetaddr_chain); static BLOCKING_NOTIFIER_HEAD(inetaddr_validator_chain); static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr __rcu **ifap, int destroy); #ifdef CONFIG_SYSCTL static int devinet_sysctl_register(struct in_device *idev); static void devinet_sysctl_unregister(struct in_device *idev); #else static int devinet_sysctl_register(struct in_device *idev) { return 0; } static void devinet_sysctl_unregister(struct in_device *idev) { } #endif /* Locks all the inet devices. */ static struct in_ifaddr *inet_alloc_ifa(void) { return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL_ACCOUNT); } static void inet_rcu_free_ifa(struct rcu_head *head) { struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head); if (ifa->ifa_dev) in_dev_put(ifa->ifa_dev); kfree(ifa); } static void inet_free_ifa(struct in_ifaddr *ifa) { call_rcu(&ifa->rcu_head, inet_rcu_free_ifa); } static void in_dev_free_rcu(struct rcu_head *head) { struct in_device *idev = container_of(head, struct in_device, rcu_head); kfree(rcu_dereference_protected(idev->mc_hash, 1)); kfree(idev); } void in_dev_finish_destroy(struct in_device *idev) { struct net_device *dev = idev->dev; WARN_ON(idev->ifa_list); WARN_ON(idev->mc_list); #ifdef NET_REFCNT_DEBUG pr_debug("%s: %p=%s\n", __func__, idev, dev ? dev->name : "NIL"); #endif netdev_put(dev, &idev->dev_tracker); if (!idev->dead) pr_err("Freeing alive in_device %p\n", idev); else call_rcu(&idev->rcu_head, in_dev_free_rcu); } EXPORT_SYMBOL(in_dev_finish_destroy); static struct in_device *inetdev_init(struct net_device *dev) { struct in_device *in_dev; int err = -ENOMEM; ASSERT_RTNL(); in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL); if (!in_dev) goto out; memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt, sizeof(in_dev->cnf)); in_dev->cnf.sysctl = NULL; in_dev->dev = dev; in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl); if (!in_dev->arp_parms) goto out_kfree; if (IPV4_DEVCONF(in_dev->cnf, FORWARDING)) dev_disable_lro(dev); /* Reference in_dev->dev */ netdev_hold(dev, &in_dev->dev_tracker, GFP_KERNEL); /* Account for reference dev->ip_ptr (below) */ refcount_set(&in_dev->refcnt, 1); err = devinet_sysctl_register(in_dev); if (err) { in_dev->dead = 1; neigh_parms_release(&arp_tbl, in_dev->arp_parms); in_dev_put(in_dev); in_dev = NULL; goto out; } ip_mc_init_dev(in_dev); if (dev->flags & IFF_UP) ip_mc_up(in_dev); /* we can receive as soon as ip_ptr is set -- do this last */ rcu_assign_pointer(dev->ip_ptr, in_dev); out: return in_dev ?: ERR_PTR(err); out_kfree: kfree(in_dev); in_dev = NULL; goto out; } static void inetdev_destroy(struct in_device *in_dev) { struct net_device *dev; struct in_ifaddr *ifa; ASSERT_RTNL(); dev = in_dev->dev; in_dev->dead = 1; ip_mc_destroy_dev(in_dev); while ((ifa = rtnl_dereference(in_dev->ifa_list)) != NULL) { inet_del_ifa(in_dev, &in_dev->ifa_list, 0); inet_free_ifa(ifa); } RCU_INIT_POINTER(dev->ip_ptr, NULL); devinet_sysctl_unregister(in_dev); neigh_parms_release(&arp_tbl, in_dev->arp_parms); arp_ifdown(dev); in_dev_put(in_dev); } int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b) { const struct in_ifaddr *ifa; rcu_read_lock(); in_dev_for_each_ifa_rcu(ifa, in_dev) { if (inet_ifa_match(a, ifa)) { if (!b || inet_ifa_match(b, ifa)) { rcu_read_unlock(); return 1; } } } rcu_read_unlock(); return 0; } static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr __rcu **ifap, int destroy, struct nlmsghdr *nlh, u32 portid) { struct in_ifaddr *promote = NULL; struct in_ifaddr *ifa, *ifa1; struct in_ifaddr __rcu **last_prim; struct in_ifaddr *prev_prom = NULL; int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev); ASSERT_RTNL(); ifa1 = rtnl_dereference(*ifap); last_prim = ifap; if (in_dev->dead) goto no_promotions; /* 1. Deleting primary ifaddr forces deletion all secondaries * unless alias promotion is set **/ if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) { struct in_ifaddr __rcu **ifap1 = &ifa1->ifa_next; while ((ifa = rtnl_dereference(*ifap1)) != NULL) { if (!(ifa->ifa_flags & IFA_F_SECONDARY) && ifa1->ifa_scope <= ifa->ifa_scope) last_prim = &ifa->ifa_next; if (!(ifa->ifa_flags & IFA_F_SECONDARY) || ifa1->ifa_mask != ifa->ifa_mask || !inet_ifa_match(ifa1->ifa_address, ifa)) { ifap1 = &ifa->ifa_next; prev_prom = ifa; continue; } if (!do_promote) { inet_hash_remove(ifa); *ifap1 = ifa->ifa_next; rtmsg_ifa(RTM_DELADDR, ifa, nlh, portid); blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa); inet_free_ifa(ifa); } else { promote = ifa; break; } } } /* On promotion all secondaries from subnet are changing * the primary IP, we must remove all their routes silently * and later to add them back with new prefsrc. Do this * while all addresses are on the device list. */ for (ifa = promote; ifa; ifa = rtnl_dereference(ifa->ifa_next)) { if (ifa1->ifa_mask == ifa->ifa_mask && inet_ifa_match(ifa1->ifa_address, ifa)) fib_del_ifaddr(ifa, ifa1); } no_promotions: /* 2. Unlink it */ *ifap = ifa1->ifa_next; inet_hash_remove(ifa1); /* 3. Announce address deletion */ /* Send message first, then call notifier. At first sight, FIB update triggered by notifier will refer to already deleted ifaddr, that could confuse netlink listeners. It is not true: look, gated sees that route deleted and if it still thinks that ifaddr is valid, it will try to restore deleted routes... Grr. So that, this order is correct. */ rtmsg_ifa(RTM_DELADDR, ifa1, nlh, portid); blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1); if (promote) { struct in_ifaddr *next_sec; next_sec = rtnl_dereference(promote->ifa_next); if (prev_prom) { struct in_ifaddr *last_sec; rcu_assign_pointer(prev_prom->ifa_next, next_sec); last_sec = rtnl_dereference(*last_prim); rcu_assign_pointer(promote->ifa_next, last_sec); rcu_assign_pointer(*last_prim, promote); } promote->ifa_flags &= ~IFA_F_SECONDARY; rtmsg_ifa(RTM_NEWADDR, promote, nlh, portid); blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, promote); for (ifa = next_sec; ifa; ifa = rtnl_dereference(ifa->ifa_next)) { if (ifa1->ifa_mask != ifa->ifa_mask || !inet_ifa_match(ifa1->ifa_address, ifa)) continue; fib_add_ifaddr(ifa); } } if (destroy) inet_free_ifa(ifa1); } static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr __rcu **ifap, int destroy) { __inet_del_ifa(in_dev, ifap, destroy, NULL, 0); } static void check_lifetime(struct work_struct *work); static DECLARE_DELAYED_WORK(check_lifetime_work, check_lifetime); static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh, u32 portid, struct netlink_ext_ack *extack) { struct in_ifaddr __rcu **last_primary, **ifap; struct in_device *in_dev = ifa->ifa_dev; struct in_validator_info ivi; struct in_ifaddr *ifa1; int ret; ASSERT_RTNL(); if (!ifa->ifa_local) { inet_free_ifa(ifa); return 0; } ifa->ifa_flags &= ~IFA_F_SECONDARY; last_primary = &in_dev->ifa_list; /* Don't set IPv6 only flags to IPv4 addresses */ ifa->ifa_flags &= ~IPV6ONLY_FLAGS; ifap = &in_dev->ifa_list; ifa1 = rtnl_dereference(*ifap); while (ifa1) { if (!(ifa1->ifa_flags & IFA_F_SECONDARY) && ifa->ifa_scope <= ifa1->ifa_scope) last_primary = &ifa1->ifa_next; if (ifa1->ifa_mask == ifa->ifa_mask && inet_ifa_match(ifa1->ifa_address, ifa)) { if (ifa1->ifa_local == ifa->ifa_local) { inet_free_ifa(ifa); return -EEXIST; } if (ifa1->ifa_scope != ifa->ifa_scope) { NL_SET_ERR_MSG(extack, "ipv4: Invalid scope value"); inet_free_ifa(ifa); return -EINVAL; } ifa->ifa_flags |= IFA_F_SECONDARY; } ifap = &ifa1->ifa_next; ifa1 = rtnl_dereference(*ifap); } /* Allow any devices that wish to register ifaddr validtors to weigh * in now, before changes are committed. The rntl lock is serializing * access here, so the state should not change between a validator call * and a final notify on commit. This isn't invoked on promotion under * the assumption that validators are checking the address itself, and * not the flags. */ ivi.ivi_addr = ifa->ifa_address; ivi.ivi_dev = ifa->ifa_dev; ivi.extack = extack; ret = blocking_notifier_call_chain(&inetaddr_validator_chain, NETDEV_UP, &ivi); ret = notifier_to_errno(ret); if (ret) { inet_free_ifa(ifa); return ret; } if (!(ifa->ifa_flags & IFA_F_SECONDARY)) ifap = last_primary; rcu_assign_pointer(ifa->ifa_next, *ifap); rcu_assign_pointer(*ifap, ifa); inet_hash_insert(dev_net(in_dev->dev), ifa); cancel_delayed_work(&check_lifetime_work); queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0); /* Send message first, then call notifier. Notifier will trigger FIB update, so that listeners of netlink will know about new ifaddr */ rtmsg_ifa(RTM_NEWADDR, ifa, nlh, portid); blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa); return 0; } static int inet_insert_ifa(struct in_ifaddr *ifa) { return __inet_insert_ifa(ifa, NULL, 0, NULL); } static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa) { struct in_device *in_dev = __in_dev_get_rtnl(dev); ASSERT_RTNL(); if (!in_dev) { inet_free_ifa(ifa); return -ENOBUFS; } ipv4_devconf_setall(in_dev); neigh_parms_data_state_setall(in_dev->arp_parms); if (ifa->ifa_dev != in_dev) { WARN_ON(ifa->ifa_dev); in_dev_hold(in_dev); ifa->ifa_dev = in_dev; } if (ipv4_is_loopback(ifa->ifa_local)) ifa->ifa_scope = RT_SCOPE_HOST; return inet_insert_ifa(ifa); } /* Caller must hold RCU or RTNL : * We dont take a reference on found in_device */ struct in_device *inetdev_by_index(struct net *net, int ifindex) { struct net_device *dev; struct in_device *in_dev = NULL; rcu_read_lock(); dev = dev_get_by_index_rcu(net, ifindex); if (dev) in_dev = rcu_dereference_rtnl(dev->ip_ptr); rcu_read_unlock(); return in_dev; } EXPORT_SYMBOL(inetdev_by_index); /* Called only from RTNL semaphored context. No locks. */ struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix, __be32 mask) { struct in_ifaddr *ifa; ASSERT_RTNL(); in_dev_for_each_ifa_rtnl(ifa, in_dev) { if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa)) return ifa; } return NULL; } static int ip_mc_autojoin_config(struct net *net, bool join, const struct in_ifaddr *ifa) { #if defined(CONFIG_IP_MULTICAST) struct ip_mreqn mreq = { .imr_multiaddr.s_addr = ifa->ifa_address, .imr_ifindex = ifa->ifa_dev->dev->ifindex, }; struct sock *sk = net->ipv4.mc_autojoin_sk; int ret; ASSERT_RTNL(); lock_sock(sk); if (join) ret = ip_mc_join_group(sk, &mreq); else ret = ip_mc_leave_group(sk, &mreq); release_sock(sk); return ret; #else return -EOPNOTSUPP; #endif } static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct in_ifaddr __rcu **ifap; struct nlattr *tb[IFA_MAX+1]; struct in_device *in_dev; struct ifaddrmsg *ifm; struct in_ifaddr *ifa; int err; ASSERT_RTNL(); err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy, extack); if (err < 0) goto errout; ifm = nlmsg_data(nlh); in_dev = inetdev_by_index(net, ifm->ifa_index); if (!in_dev) { NL_SET_ERR_MSG(extack, "ipv4: Device not found"); err = -ENODEV; goto errout; } for (ifap = &in_dev->ifa_list; (ifa = rtnl_dereference(*ifap)) != NULL; ifap = &ifa->ifa_next) { if (tb[IFA_LOCAL] && ifa->ifa_local != nla_get_in_addr(tb[IFA_LOCAL])) continue; if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label)) continue; if (tb[IFA_ADDRESS] && (ifm->ifa_prefixlen != ifa->ifa_prefixlen || !inet_ifa_match(nla_get_in_addr(tb[IFA_ADDRESS]), ifa))) continue; if (ipv4_is_multicast(ifa->ifa_address)) ip_mc_autojoin_config(net, false, ifa); __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).portid); return 0; } NL_SET_ERR_MSG(extack, "ipv4: Address not found"); err = -EADDRNOTAVAIL; errout: return err; } #define INFINITY_LIFE_TIME 0xFFFFFFFF static void check_lifetime(struct work_struct *work) { unsigned long now, next, next_sec, next_sched; struct in_ifaddr *ifa; struct hlist_node *n; int i; now = jiffies; next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY); for (i = 0; i < IN4_ADDR_HSIZE; i++) { bool change_needed = false; rcu_read_lock(); hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) { unsigned long age; if (ifa->ifa_flags & IFA_F_PERMANENT) continue; /* We try to batch several events at once. */ age = (now - ifa->ifa_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ; if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME && age >= ifa->ifa_valid_lft) { change_needed = true; } else if (ifa->ifa_preferred_lft == INFINITY_LIFE_TIME) { continue; } else if (age >= ifa->ifa_preferred_lft) { if (time_before(ifa->ifa_tstamp + ifa->ifa_valid_lft * HZ, next)) next = ifa->ifa_tstamp + ifa->ifa_valid_lft * HZ; if (!(ifa->ifa_flags & IFA_F_DEPRECATED)) change_needed = true; } else if (time_before(ifa->ifa_tstamp + ifa->ifa_preferred_lft * HZ, next)) { next = ifa->ifa_tstamp + ifa->ifa_preferred_lft * HZ; } } rcu_read_unlock(); if (!change_needed) continue; rtnl_lock(); hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) { unsigned long age; if (ifa->ifa_flags & IFA_F_PERMANENT) continue; /* We try to batch several events at once. */ age = (now - ifa->ifa_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ; if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME && age >= ifa->ifa_valid_lft) { struct in_ifaddr __rcu **ifap; struct in_ifaddr *tmp; ifap = &ifa->ifa_dev->ifa_list; tmp = rtnl_dereference(*ifap); while (tmp) { if (tmp == ifa) { inet_del_ifa(ifa->ifa_dev, ifap, 1); break; } ifap = &tmp->ifa_next; tmp = rtnl_dereference(*ifap); } } else if (ifa->ifa_preferred_lft != INFINITY_LIFE_TIME && age >= ifa->ifa_preferred_lft && !(ifa->ifa_flags & IFA_F_DEPRECATED)) { ifa->ifa_flags |= IFA_F_DEPRECATED; rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0); } } rtnl_unlock(); } next_sec = round_jiffies_up(next); next_sched = next; /* If rounded timeout is accurate enough, accept it. */ if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ)) next_sched = next_sec; now = jiffies; /* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */ if (time_before(next_sched, now + ADDRCONF_TIMER_FUZZ_MAX)) next_sched = now + ADDRCONF_TIMER_FUZZ_MAX; queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, next_sched - now); } static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft, __u32 prefered_lft) { unsigned long timeout; ifa->ifa_flags &= ~(IFA_F_PERMANENT | IFA_F_DEPRECATED); timeout = addrconf_timeout_fixup(valid_lft, HZ); if (addrconf_finite_timeout(timeout)) ifa->ifa_valid_lft = timeout; else ifa->ifa_flags |= IFA_F_PERMANENT; timeout = addrconf_timeout_fixup(prefered_lft, HZ); if (addrconf_finite_timeout(timeout)) { if (timeout == 0) ifa->ifa_flags |= IFA_F_DEPRECATED; ifa->ifa_preferred_lft = timeout; } ifa->ifa_tstamp = jiffies; if (!ifa->ifa_cstamp) ifa->ifa_cstamp = ifa->ifa_tstamp; } static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh, __u32 *pvalid_lft, __u32 *pprefered_lft, struct netlink_ext_ack *extack) { struct nlattr *tb[IFA_MAX+1]; struct in_ifaddr *ifa; struct ifaddrmsg *ifm; struct net_device *dev; struct in_device *in_dev; int err; err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy, extack); if (err < 0) goto errout; ifm = nlmsg_data(nlh); err = -EINVAL; if (ifm->ifa_prefixlen > 32) { NL_SET_ERR_MSG(extack, "ipv4: Invalid prefix length"); goto errout; } if (!tb[IFA_LOCAL]) { NL_SET_ERR_MSG(extack, "ipv4: Local address is not supplied"); goto errout; } dev = __dev_get_by_index(net, ifm->ifa_index); err = -ENODEV; if (!dev) { NL_SET_ERR_MSG(extack, "ipv4: Device not found"); goto errout; } in_dev = __in_dev_get_rtnl(dev); err = -ENOBUFS; if (!in_dev) goto errout; ifa = inet_alloc_ifa(); if (!ifa) /* * A potential indev allocation can be left alive, it stays * assigned to its device and is destroy with it. */ goto errout; ipv4_devconf_setall(in_dev); neigh_parms_data_state_setall(in_dev->arp_parms); in_dev_hold(in_dev); if (!tb[IFA_ADDRESS]) tb[IFA_ADDRESS] = tb[IFA_LOCAL]; INIT_HLIST_NODE(&ifa->hash); ifa->ifa_prefixlen = ifm->ifa_prefixlen; ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen); ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags; ifa->ifa_scope = ifm->ifa_scope; ifa->ifa_dev = in_dev; ifa->ifa_local = nla_get_in_addr(tb[IFA_LOCAL]); ifa->ifa_address = nla_get_in_addr(tb[IFA_ADDRESS]); if (tb[IFA_BROADCAST]) ifa->ifa_broadcast = nla_get_in_addr(tb[IFA_BROADCAST]); if (tb[IFA_LABEL]) nla_strscpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ); else memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); if (tb[IFA_RT_PRIORITY]) ifa->ifa_rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]); if (tb[IFA_PROTO]) ifa->ifa_proto = nla_get_u8(tb[IFA_PROTO]); if (tb[IFA_CACHEINFO]) { struct ifa_cacheinfo *ci; ci = nla_data(tb[IFA_CACHEINFO]); if (!ci->ifa_valid || ci->ifa_prefered > ci->ifa_valid) { NL_SET_ERR_MSG(extack, "ipv4: address lifetime invalid"); err = -EINVAL; goto errout_free; } *pvalid_lft = ci->ifa_valid; *pprefered_lft = ci->ifa_prefered; } return ifa; errout_free: inet_free_ifa(ifa); errout: return ERR_PTR(err); } static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa) { struct in_device *in_dev = ifa->ifa_dev; struct in_ifaddr *ifa1; if (!ifa->ifa_local) return NULL; in_dev_for_each_ifa_rtnl(ifa1, in_dev) { if (ifa1->ifa_mask == ifa->ifa_mask && inet_ifa_match(ifa1->ifa_address, ifa) && ifa1->ifa_local == ifa->ifa_local) return ifa1; } return NULL; } static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct in_ifaddr *ifa; struct in_ifaddr *ifa_existing; __u32 valid_lft = INFINITY_LIFE_TIME; __u32 prefered_lft = INFINITY_LIFE_TIME; ASSERT_RTNL(); ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft, extack); if (IS_ERR(ifa)) return PTR_ERR(ifa); ifa_existing = find_matching_ifa(ifa); if (!ifa_existing) { /* It would be best to check for !NLM_F_CREATE here but * userspace already relies on not having to provide this. */ set_ifa_lifetime(ifa, valid_lft, prefered_lft); if (ifa->ifa_flags & IFA_F_MCAUTOJOIN) { int ret = ip_mc_autojoin_config(net, true, ifa); if (ret < 0) { NL_SET_ERR_MSG(extack, "ipv4: Multicast auto join failed"); inet_free_ifa(ifa); return ret; } } return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).portid, extack); } else { u32 new_metric = ifa->ifa_rt_priority; u8 new_proto = ifa->ifa_proto; inet_free_ifa(ifa); if (nlh->nlmsg_flags & NLM_F_EXCL || !(nlh->nlmsg_flags & NLM_F_REPLACE)) { NL_SET_ERR_MSG(extack, "ipv4: Address already assigned"); return -EEXIST; } ifa = ifa_existing; if (ifa->ifa_rt_priority != new_metric) { fib_modify_prefix_metric(ifa, new_metric); ifa->ifa_rt_priority = new_metric; } ifa->ifa_proto = new_proto; set_ifa_lifetime(ifa, valid_lft, prefered_lft); cancel_delayed_work(&check_lifetime_work); queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0); rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid); } return 0; } /* * Determine a default network mask, based on the IP address. */ static int inet_abc_len(__be32 addr) { int rc = -1; /* Something else, probably a multicast. */ if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr)) rc = 0; else { __u32 haddr = ntohl(addr); if (IN_CLASSA(haddr)) rc = 8; else if (IN_CLASSB(haddr)) rc = 16; else if (IN_CLASSC(haddr)) rc = 24; else if (IN_CLASSE(haddr)) rc = 32; } return rc; } int devinet_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr) { struct sockaddr_in sin_orig; struct sockaddr_in *sin = (struct sockaddr_in *)&ifr->ifr_addr; struct in_ifaddr __rcu **ifap = NULL; struct in_device *in_dev; struct in_ifaddr *ifa = NULL; struct net_device *dev; char *colon; int ret = -EFAULT; int tryaddrmatch = 0; ifr->ifr_name[IFNAMSIZ - 1] = 0; /* save original address for comparison */ memcpy(&sin_orig, sin, sizeof(*sin)); colon = strchr(ifr->ifr_name, ':'); if (colon) *colon = 0; dev_load(net, ifr->ifr_name); switch (cmd) { case SIOCGIFADDR: /* Get interface address */ case SIOCGIFBRDADDR: /* Get the broadcast address */ case SIOCGIFDSTADDR: /* Get the destination address */ case SIOCGIFNETMASK: /* Get the netmask for the interface */ /* Note that these ioctls will not sleep, so that we do not impose a lock. One day we will be forced to put shlock here (I mean SMP) */ tryaddrmatch = (sin_orig.sin_family == AF_INET); memset(sin, 0, sizeof(*sin)); sin->sin_family = AF_INET; break; case SIOCSIFFLAGS: ret = -EPERM; if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) goto out; break; case SIOCSIFADDR: /* Set interface address (and family) */ case SIOCSIFBRDADDR: /* Set the broadcast address */ case SIOCSIFDSTADDR: /* Set the destination address */ case SIOCSIFNETMASK: /* Set the netmask for the interface */ ret = -EPERM; if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) goto out; ret = -EINVAL; if (sin->sin_family != AF_INET) goto out; break; default: ret = -EINVAL; goto out; } rtnl_lock(); ret = -ENODEV; dev = __dev_get_by_name(net, ifr->ifr_name); if (!dev) goto done; if (colon) *colon = ':'; in_dev = __in_dev_get_rtnl(dev); if (in_dev) { if (tryaddrmatch) { /* Matthias Andree */ /* compare label and address (4.4BSD style) */ /* note: we only do this for a limited set of ioctls and only if the original address family was AF_INET. This is checked above. */ for (ifap = &in_dev->ifa_list; (ifa = rtnl_dereference(*ifap)) != NULL; ifap = &ifa->ifa_next) { if (!strcmp(ifr->ifr_name, ifa->ifa_label) && sin_orig.sin_addr.s_addr == ifa->ifa_local) { break; /* found */ } } } /* we didn't get a match, maybe the application is 4.3BSD-style and passed in junk so we fall back to comparing just the label */ if (!ifa) { for (ifap = &in_dev->ifa_list; (ifa = rtnl_dereference(*ifap)) != NULL; ifap = &ifa->ifa_next) if (!strcmp(ifr->ifr_name, ifa->ifa_label)) break; } } ret = -EADDRNOTAVAIL; if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS) goto done; switch (cmd) { case SIOCGIFADDR: /* Get interface address */ ret = 0; sin->sin_addr.s_addr = ifa->ifa_local; break; case SIOCGIFBRDADDR: /* Get the broadcast address */ ret = 0; sin->sin_addr.s_addr = ifa->ifa_broadcast; break; case SIOCGIFDSTADDR: /* Get the destination address */ ret = 0; sin->sin_addr.s_addr = ifa->ifa_address; break; case SIOCGIFNETMASK: /* Get the netmask for the interface */ ret = 0; sin->sin_addr.s_addr = ifa->ifa_mask; break; case SIOCSIFFLAGS: if (colon) { ret = -EADDRNOTAVAIL; if (!ifa) break; ret = 0; if (!(ifr->ifr_flags & IFF_UP)) inet_del_ifa(in_dev, ifap, 1); break; } ret = dev_change_flags(dev, ifr->ifr_flags, NULL); break; case SIOCSIFADDR: /* Set interface address (and family) */ ret = -EINVAL; if (inet_abc_len(sin->sin_addr.s_addr) < 0) break; if (!ifa) { ret = -ENOBUFS; ifa = inet_alloc_ifa(); if (!ifa) break; INIT_HLIST_NODE(&ifa->hash); if (colon) memcpy(ifa->ifa_label, ifr->ifr_name, IFNAMSIZ); else memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); } else { ret = 0; if (ifa->ifa_local == sin->sin_addr.s_addr) break; inet_del_ifa(in_dev, ifap, 0); ifa->ifa_broadcast = 0; ifa->ifa_scope = 0; } ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr; if (!(dev->flags & IFF_POINTOPOINT)) { ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address); ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen); if ((dev->flags & IFF_BROADCAST) && ifa->ifa_prefixlen < 31) ifa->ifa_broadcast = ifa->ifa_address | ~ifa->ifa_mask; } else { ifa->ifa_prefixlen = 32; ifa->ifa_mask = inet_make_mask(32); } set_ifa_lifetime(ifa, INFINITY_LIFE_TIME, INFINITY_LIFE_TIME); ret = inet_set_ifa(dev, ifa); break; case SIOCSIFBRDADDR: /* Set the broadcast address */ ret = 0; if (ifa->ifa_broadcast != sin->sin_addr.s_addr) { inet_del_ifa(in_dev, ifap, 0); ifa->ifa_broadcast = sin->sin_addr.s_addr; inet_insert_ifa(ifa); } break; case SIOCSIFDSTADDR: /* Set the destination address */ ret = 0; if (ifa->ifa_address == sin->sin_addr.s_addr) break; ret = -EINVAL; if (inet_abc_len(sin->sin_addr.s_addr) < 0) break; ret = 0; inet_del_ifa(in_dev, ifap, 0); ifa->ifa_address = sin->sin_addr.s_addr; inet_insert_ifa(ifa); break; case SIOCSIFNETMASK: /* Set the netmask for the interface */ /* * The mask we set must be legal. */ ret = -EINVAL; if (bad_mask(sin->sin_addr.s_addr, 0)) break; ret = 0; if (ifa->ifa_mask != sin->sin_addr.s_addr) { __be32 old_mask = ifa->ifa_mask; inet_del_ifa(in_dev, ifap, 0); ifa->ifa_mask = sin->sin_addr.s_addr; ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask); /* See if current broadcast address matches * with current netmask, then recalculate * the broadcast address. Otherwise it's a * funny address, so don't touch it since * the user seems to know what (s)he's doing... */ if ((dev->flags & IFF_BROADCAST) && (ifa->ifa_prefixlen < 31) && (ifa->ifa_broadcast == (ifa->ifa_local|~old_mask))) { ifa->ifa_broadcast = (ifa->ifa_local | ~sin->sin_addr.s_addr); } inet_insert_ifa(ifa); } break; } done: rtnl_unlock(); out: return ret; } int inet_gifconf(struct net_device *dev, char __user *buf, int len, int size) { struct in_device *in_dev = __in_dev_get_rtnl(dev); const struct in_ifaddr *ifa; struct ifreq ifr; int done = 0; if (WARN_ON(size > sizeof(struct ifreq))) goto out; if (!in_dev) goto out; in_dev_for_each_ifa_rtnl(ifa, in_dev) { if (!buf) { done += size; continue; } if (len < size) break; memset(&ifr, 0, sizeof(struct ifreq)); strcpy(ifr.ifr_name, ifa->ifa_label); (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET; (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr = ifa->ifa_local; if (copy_to_user(buf + done, &ifr, size)) { done = -EFAULT; break; } len -= size; done += size; } out: return done; } static __be32 in_dev_select_addr(const struct in_device *in_dev, int scope) { const struct in_ifaddr *ifa; in_dev_for_each_ifa_rcu(ifa, in_dev) { if (ifa->ifa_flags & IFA_F_SECONDARY) continue; if (ifa->ifa_scope != RT_SCOPE_LINK && ifa->ifa_scope <= scope) return ifa->ifa_local; } return 0; } __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope) { const struct in_ifaddr *ifa; __be32 addr = 0; unsigned char localnet_scope = RT_SCOPE_HOST; struct in_device *in_dev; struct net *net = dev_net(dev); int master_idx; rcu_read_lock(); in_dev = __in_dev_get_rcu(dev); if (!in_dev) goto no_in_dev; if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev))) localnet_scope = RT_SCOPE_LINK; in_dev_for_each_ifa_rcu(ifa, in_dev) { if (ifa->ifa_flags & IFA_F_SECONDARY) continue; if (min(ifa->ifa_scope, localnet_scope) > scope) continue; if (!dst || inet_ifa_match(dst, ifa)) { addr = ifa->ifa_local; break; } if (!addr) addr = ifa->ifa_local; } if (addr) goto out_unlock; no_in_dev: master_idx = l3mdev_master_ifindex_rcu(dev); /* For VRFs, the VRF device takes the place of the loopback device, * with addresses on it being preferred. Note in such cases the * loopback device will be among the devices that fail the master_idx * equality check in the loop below. */ if (master_idx && (dev = dev_get_by_index_rcu(net, master_idx)) && (in_dev = __in_dev_get_rcu(dev))) { addr = in_dev_select_addr(in_dev, scope); if (addr) goto out_unlock; } /* Not loopback addresses on loopback should be preferred in this case. It is important that lo is the first interface in dev_base list. */ for_each_netdev_rcu(net, dev) { if (l3mdev_master_ifindex_rcu(dev) != master_idx) continue; in_dev = __in_dev_get_rcu(dev); if (!in_dev) continue; addr = in_dev_select_addr(in_dev, scope); if (addr) goto out_unlock; } out_unlock: rcu_read_unlock(); return addr; } EXPORT_SYMBOL(inet_select_addr); static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst, __be32 local, int scope) { unsigned char localnet_scope = RT_SCOPE_HOST; const struct in_ifaddr *ifa; __be32 addr = 0; int same = 0; if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev))) localnet_scope = RT_SCOPE_LINK; in_dev_for_each_ifa_rcu(ifa, in_dev) { unsigned char min_scope = min(ifa->ifa_scope, localnet_scope); if (!addr && (local == ifa->ifa_local || !local) && min_scope <= scope) { addr = ifa->ifa_local; if (same) break; } if (!same) { same = (!local || inet_ifa_match(local, ifa)) && (!dst || inet_ifa_match(dst, ifa)); if (same && addr) { if (local || !dst) break; /* Is the selected addr into dst subnet? */ if (inet_ifa_match(addr, ifa)) break; /* No, then can we use new local src? */ if (min_scope <= scope) { addr = ifa->ifa_local; break; } /* search for large dst subnet for addr */ same = 0; } } } return same ? addr : 0; } /* * Confirm that local IP address exists using wildcards: * - net: netns to check, cannot be NULL * - in_dev: only on this interface, NULL=any interface * - dst: only in the same subnet as dst, 0=any dst * - local: address, 0=autoselect the local address * - scope: maximum allowed scope value for the local address */ __be32 inet_confirm_addr(struct net *net, struct in_device *in_dev, __be32 dst, __be32 local, int scope) { __be32 addr = 0; struct net_device *dev; if (in_dev) return confirm_addr_indev(in_dev, dst, local, scope); rcu_read_lock(); for_each_netdev_rcu(net, dev) { in_dev = __in_dev_get_rcu(dev); if (in_dev) { addr = confirm_addr_indev(in_dev, dst, local, scope); if (addr) break; } } rcu_read_unlock(); return addr; } EXPORT_SYMBOL(inet_confirm_addr); /* * Device notifier */ int register_inetaddr_notifier(struct notifier_block *nb) { return blocking_notifier_chain_register(&inetaddr_chain, nb); } EXPORT_SYMBOL(register_inetaddr_notifier); int unregister_inetaddr_notifier(struct notifier_block *nb) { return blocking_notifier_chain_unregister(&inetaddr_chain, nb); } EXPORT_SYMBOL(unregister_inetaddr_notifier); int register_inetaddr_validator_notifier(struct notifier_block *nb) { return blocking_notifier_chain_register(&inetaddr_validator_chain, nb); } EXPORT_SYMBOL(register_inetaddr_validator_notifier); int unregister_inetaddr_validator_notifier(struct notifier_block *nb) { return blocking_notifier_chain_unregister(&inetaddr_validator_chain, nb); } EXPORT_SYMBOL(unregister_inetaddr_validator_notifier); /* Rename ifa_labels for a device name change. Make some effort to preserve * existing alias numbering and to create unique labels if possible. */ static void inetdev_changename(struct net_device *dev, struct in_device *in_dev) { struct in_ifaddr *ifa; int named = 0; in_dev_for_each_ifa_rtnl(ifa, in_dev) { char old[IFNAMSIZ], *dot; memcpy(old, ifa->ifa_label, IFNAMSIZ); memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); if (named++ == 0) goto skip; dot = strchr(old, ':'); if (!dot) { sprintf(old, ":%d", named); dot = old; } if (strlen(dot) + strlen(dev->name) < IFNAMSIZ) strcat(ifa->ifa_label, dot); else strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot); skip: rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0); } } static void inetdev_send_gratuitous_arp(struct net_device *dev, struct in_device *in_dev) { const struct in_ifaddr *ifa; in_dev_for_each_ifa_rtnl(ifa, in_dev) { arp_send(ARPOP_REQUEST, ETH_P_ARP, ifa->ifa_local, dev, ifa->ifa_local, NULL, dev->dev_addr, NULL); } } /* Called only under RTNL semaphore */ static int inetdev_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct in_device *in_dev = __in_dev_get_rtnl(dev); ASSERT_RTNL(); if (!in_dev) { if (event == NETDEV_REGISTER) { in_dev = inetdev_init(dev); if (IS_ERR(in_dev)) return notifier_from_errno(PTR_ERR(in_dev)); if (dev->flags & IFF_LOOPBACK) { IN_DEV_CONF_SET(in_dev, NOXFRM, 1); IN_DEV_CONF_SET(in_dev, NOPOLICY, 1); } } else if (event == NETDEV_CHANGEMTU) { /* Re-enabling IP */ if (inetdev_valid_mtu(dev->mtu)) in_dev = inetdev_init(dev); } goto out; } switch (event) { case NETDEV_REGISTER: pr_debug("%s: bug\n", __func__); RCU_INIT_POINTER(dev->ip_ptr, NULL); break; case NETDEV_UP: if (!inetdev_valid_mtu(dev->mtu)) break; if (dev->flags & IFF_LOOPBACK) { struct in_ifaddr *ifa = inet_alloc_ifa(); if (ifa) { INIT_HLIST_NODE(&ifa->hash); ifa->ifa_local = ifa->ifa_address = htonl(INADDR_LOOPBACK); ifa->ifa_prefixlen = 8; ifa->ifa_mask = inet_make_mask(8); in_dev_hold(in_dev); ifa->ifa_dev = in_dev; ifa->ifa_scope = RT_SCOPE_HOST; memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); set_ifa_lifetime(ifa, INFINITY_LIFE_TIME, INFINITY_LIFE_TIME); ipv4_devconf_setall(in_dev); neigh_parms_data_state_setall(in_dev->arp_parms); inet_insert_ifa(ifa); } } ip_mc_up(in_dev); fallthrough; case NETDEV_CHANGEADDR: if (!IN_DEV_ARP_NOTIFY(in_dev)) break; fallthrough; case NETDEV_NOTIFY_PEERS: /* Send gratuitous ARP to notify of link change */ inetdev_send_gratuitous_arp(dev, in_dev); break; case NETDEV_DOWN: ip_mc_down(in_dev); break; case NETDEV_PRE_TYPE_CHANGE: ip_mc_unmap(in_dev); break; case NETDEV_POST_TYPE_CHANGE: ip_mc_remap(in_dev); break; case NETDEV_CHANGEMTU: if (inetdev_valid_mtu(dev->mtu)) break; /* disable IP when MTU is not enough */ fallthrough; case NETDEV_UNREGISTER: inetdev_destroy(in_dev); break; case NETDEV_CHANGENAME: /* Do not notify about label change, this event is * not interesting to applications using netlink. */ inetdev_changename(dev, in_dev); devinet_sysctl_unregister(in_dev); devinet_sysctl_register(in_dev); break; } out: return NOTIFY_DONE; } static struct notifier_block ip_netdev_notifier = { .notifier_call = inetdev_event, }; static size_t inet_nlmsg_size(void) { return NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + nla_total_size(4) /* IFA_ADDRESS */ + nla_total_size(4) /* IFA_LOCAL */ + nla_total_size(4) /* IFA_BROADCAST */ + nla_total_size(IFNAMSIZ) /* IFA_LABEL */ + nla_total_size(4) /* IFA_FLAGS */ + nla_total_size(1) /* IFA_PROTO */ + nla_total_size(4) /* IFA_RT_PRIORITY */ + nla_total_size(sizeof(struct ifa_cacheinfo)); /* IFA_CACHEINFO */ } static inline u32 cstamp_delta(unsigned long cstamp) { return (cstamp - INITIAL_JIFFIES) * 100UL / HZ; } static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp, unsigned long tstamp, u32 preferred, u32 valid) { struct ifa_cacheinfo ci; ci.cstamp = cstamp_delta(cstamp); ci.tstamp = cstamp_delta(tstamp); ci.ifa_prefered = preferred; ci.ifa_valid = valid; return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci); } static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa, struct inet_fill_args *args) { struct ifaddrmsg *ifm; struct nlmsghdr *nlh; u32 preferred, valid; nlh = nlmsg_put(skb, args->portid, args->seq, args->event, sizeof(*ifm), args->flags); if (!nlh) return -EMSGSIZE; ifm = nlmsg_data(nlh); ifm->ifa_family = AF_INET; ifm->ifa_prefixlen = ifa->ifa_prefixlen; ifm->ifa_flags = ifa->ifa_flags; ifm->ifa_scope = ifa->ifa_scope; ifm->ifa_index = ifa->ifa_dev->dev->ifindex; if (args->netnsid >= 0 && nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) goto nla_put_failure; if (!(ifm->ifa_flags & IFA_F_PERMANENT)) { preferred = ifa->ifa_preferred_lft; valid = ifa->ifa_valid_lft; if (preferred != INFINITY_LIFE_TIME) { long tval = (jiffies - ifa->ifa_tstamp) / HZ; if (preferred > tval) preferred -= tval; else preferred = 0; if (valid != INFINITY_LIFE_TIME) { if (valid > tval) valid -= tval; else valid = 0; } } } else { preferred = INFINITY_LIFE_TIME; valid = INFINITY_LIFE_TIME; } if ((ifa->ifa_address && nla_put_in_addr(skb, IFA_ADDRESS, ifa->ifa_address)) || (ifa->ifa_local && nla_put_in_addr(skb, IFA_LOCAL, ifa->ifa_local)) || (ifa->ifa_broadcast && nla_put_in_addr(skb, IFA_BROADCAST, ifa->ifa_broadcast)) || (ifa->ifa_label[0] && nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) || (ifa->ifa_proto && nla_put_u8(skb, IFA_PROTO, ifa->ifa_proto)) || nla_put_u32(skb, IFA_FLAGS, ifa->ifa_flags) || (ifa->ifa_rt_priority && nla_put_u32(skb, IFA_RT_PRIORITY, ifa->ifa_rt_priority)) || put_cacheinfo(skb, ifa->ifa_cstamp, ifa->ifa_tstamp, preferred, valid)) goto nla_put_failure; nlmsg_end(skb, nlh); return 0; nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static int inet_valid_dump_ifaddr_req(const struct nlmsghdr *nlh, struct inet_fill_args *fillargs, struct net **tgt_net, struct sock *sk, struct netlink_callback *cb) { struct netlink_ext_ack *extack = cb->extack; struct nlattr *tb[IFA_MAX+1]; struct ifaddrmsg *ifm; int err, i; if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) { NL_SET_ERR_MSG(extack, "ipv4: Invalid header for address dump request"); return -EINVAL; } ifm = nlmsg_data(nlh); if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) { NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for address dump request"); return -EINVAL; } fillargs->ifindex = ifm->ifa_index; if (fillargs->ifindex) { cb->answer_flags |= NLM_F_DUMP_FILTERED; fillargs->flags |= NLM_F_DUMP_FILTERED; } err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy, extack); if (err < 0) return err; for (i = 0; i <= IFA_MAX; ++i) { if (!tb[i]) continue; if (i == IFA_TARGET_NETNSID) { struct net *net; fillargs->netnsid = nla_get_s32(tb[i]); net = rtnl_get_net_ns_capable(sk, fillargs->netnsid); if (IS_ERR(net)) { fillargs->netnsid = -1; NL_SET_ERR_MSG(extack, "ipv4: Invalid target network namespace id"); return PTR_ERR(net); } *tgt_net = net; } else { NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in dump request"); return -EINVAL; } } return 0; } static int in_dev_dump_addr(struct in_device *in_dev, struct sk_buff *skb, struct netlink_callback *cb, int s_ip_idx, struct inet_fill_args *fillargs) { struct in_ifaddr *ifa; int ip_idx = 0; int err; in_dev_for_each_ifa_rtnl(ifa, in_dev) { if (ip_idx < s_ip_idx) { ip_idx++; continue; } err = inet_fill_ifaddr(skb, ifa, fillargs); if (err < 0) goto done; nl_dump_check_consistent(cb, nlmsg_hdr(skb)); ip_idx++; } err = 0; done: cb->args[2] = ip_idx; return err; } static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb) { const struct nlmsghdr *nlh = cb->nlh; struct inet_fill_args fillargs = { .portid = NETLINK_CB(cb->skb).portid, .seq = nlh->nlmsg_seq, .event = RTM_NEWADDR, .flags = NLM_F_MULTI, .netnsid = -1, }; struct net *net = sock_net(skb->sk); struct net *tgt_net = net; int h, s_h; int idx, s_idx; int s_ip_idx; struct net_device *dev; struct in_device *in_dev; struct hlist_head *head; int err = 0; s_h = cb->args[0]; s_idx = idx = cb->args[1]; s_ip_idx = cb->args[2]; if (cb->strict_check) { err = inet_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net, skb->sk, cb); if (err < 0) goto put_tgt_net; err = 0; if (fillargs.ifindex) { dev = __dev_get_by_index(tgt_net, fillargs.ifindex); if (!dev) { err = -ENODEV; goto put_tgt_net; } in_dev = __in_dev_get_rtnl(dev); if (in_dev) { err = in_dev_dump_addr(in_dev, skb, cb, s_ip_idx, &fillargs); } goto put_tgt_net; } } for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { idx = 0; head = &tgt_net->dev_index_head[h]; rcu_read_lock(); cb->seq = atomic_read(&tgt_net->ipv4.dev_addr_genid) ^ tgt_net->dev_base_seq; hlist_for_each_entry_rcu(dev, head, index_hlist) { if (idx < s_idx) goto cont; if (h > s_h || idx > s_idx) s_ip_idx = 0; in_dev = __in_dev_get_rcu(dev); if (!in_dev) goto cont; err = in_dev_dump_addr(in_dev, skb, cb, s_ip_idx, &fillargs); if (err < 0) { rcu_read_unlock(); goto done; } cont: idx++; } rcu_read_unlock(); } done: cb->args[0] = h; cb->args[1] = idx; put_tgt_net: if (fillargs.netnsid >= 0) put_net(tgt_net); return skb->len ? : err; } static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh, u32 portid) { struct inet_fill_args fillargs = { .portid = portid, .seq = nlh ? nlh->nlmsg_seq : 0, .event = event, .flags = 0, .netnsid = -1, }; struct sk_buff *skb; int err = -ENOBUFS; struct net *net; net = dev_net(ifa->ifa_dev->dev); skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL); if (!skb) goto errout; err = inet_fill_ifaddr(skb, ifa, &fillargs); if (err < 0) { /* -EMSGSIZE implies BUG in inet_nlmsg_size() */ WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; } rtnl_notify(skb, net, portid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL); return; errout: if (err < 0) rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err); } static size_t inet_get_link_af_size(const struct net_device *dev, u32 ext_filter_mask) { struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr); if (!in_dev) return 0; return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */ } static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev, u32 ext_filter_mask) { struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr); struct nlattr *nla; int i; if (!in_dev) return -ENODATA; nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4); if (!nla) return -EMSGSIZE; for (i = 0; i < IPV4_DEVCONF_MAX; i++) ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i]; return 0; } static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = { [IFLA_INET_CONF] = { .type = NLA_NESTED }, }; static int inet_validate_link_af(const struct net_device *dev, const struct nlattr *nla, struct netlink_ext_ack *extack) { struct nlattr *a, *tb[IFLA_INET_MAX+1]; int err, rem; if (dev && !__in_dev_get_rtnl(dev)) return -EAFNOSUPPORT; err = nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla, inet_af_policy, extack); if (err < 0) return err; if (tb[IFLA_INET_CONF]) { nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) { int cfgid = nla_type(a); if (nla_len(a) < 4) return -EINVAL; if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX) return -EINVAL; } } return 0; } static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla, struct netlink_ext_ack *extack) { struct in_device *in_dev = __in_dev_get_rtnl(dev); struct nlattr *a, *tb[IFLA_INET_MAX+1]; int rem; if (!in_dev) return -EAFNOSUPPORT; if (nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla, NULL, NULL) < 0) return -EINVAL; if (tb[IFLA_INET_CONF]) { nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a)); } return 0; } static int inet_netconf_msgsize_devconf(int type) { int size = NLMSG_ALIGN(sizeof(struct netconfmsg)) + nla_total_size(4); /* NETCONFA_IFINDEX */ bool all = false; if (type == NETCONFA_ALL) all = true; if (all || type == NETCONFA_FORWARDING) size += nla_total_size(4); if (all || type == NETCONFA_RP_FILTER) size += nla_total_size(4); if (all || type == NETCONFA_MC_FORWARDING) size += nla_total_size(4); if (all || type == NETCONFA_BC_FORWARDING) size += nla_total_size(4); if (all || type == NETCONFA_PROXY_NEIGH) size += nla_total_size(4); if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) size += nla_total_size(4); return size; } static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex, struct ipv4_devconf *devconf, u32 portid, u32 seq, int event, unsigned int flags, int type) { struct nlmsghdr *nlh; struct netconfmsg *ncm; bool all = false; nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg), flags); if (!nlh) return -EMSGSIZE; if (type == NETCONFA_ALL) all = true; ncm = nlmsg_data(nlh); ncm->ncm_family = AF_INET; if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0) goto nla_put_failure; if (!devconf) goto out; if ((all || type == NETCONFA_FORWARDING) && nla_put_s32(skb, NETCONFA_FORWARDING, IPV4_DEVCONF(*devconf, FORWARDING)) < 0) goto nla_put_failure; if ((all || type == NETCONFA_RP_FILTER) && nla_put_s32(skb, NETCONFA_RP_FILTER, IPV4_DEVCONF(*devconf, RP_FILTER)) < 0) goto nla_put_failure; if ((all || type == NETCONFA_MC_FORWARDING) && nla_put_s32(skb, NETCONFA_MC_FORWARDING, IPV4_DEVCONF(*devconf, MC_FORWARDING)) < 0) goto nla_put_failure; if ((all || type == NETCONFA_BC_FORWARDING) && nla_put_s32(skb, NETCONFA_BC_FORWARDING, IPV4_DEVCONF(*devconf, BC_FORWARDING)) < 0) goto nla_put_failure; if ((all || type == NETCONFA_PROXY_NEIGH) && nla_put_s32(skb, NETCONFA_PROXY_NEIGH, IPV4_DEVCONF(*devconf, PROXY_ARP)) < 0) goto nla_put_failure; if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) && nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN, IPV4_DEVCONF(*devconf, IGNORE_ROUTES_WITH_LINKDOWN)) < 0) goto nla_put_failure; out: nlmsg_end(skb, nlh); return 0; nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } void inet_netconf_notify_devconf(struct net *net, int event, int type, int ifindex, struct ipv4_devconf *devconf) { struct sk_buff *skb; int err = -ENOBUFS; skb = nlmsg_new(inet_netconf_msgsize_devconf(type), GFP_KERNEL); if (!skb) goto errout; err = inet_netconf_fill_devconf(skb, ifindex, devconf, 0, 0, event, 0, type); if (err < 0) { /* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */ WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; } rtnl_notify(skb, net, 0, RTNLGRP_IPV4_NETCONF, NULL, GFP_KERNEL); return; errout: if (err < 0) rtnl_set_sk_err(net, RTNLGRP_IPV4_NETCONF, err); } static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = { [NETCONFA_IFINDEX] = { .len = sizeof(int) }, [NETCONFA_FORWARDING] = { .len = sizeof(int) }, [NETCONFA_RP_FILTER] = { .len = sizeof(int) }, [NETCONFA_PROXY_NEIGH] = { .len = sizeof(int) }, [NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN] = { .len = sizeof(int) }, }; static int inet_netconf_valid_get_req(struct sk_buff *skb, const struct nlmsghdr *nlh, struct nlattr **tb, struct netlink_ext_ack *extack) { int i, err; if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) { NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf get request"); return -EINVAL; } if (!netlink_strict_get_check(skb)) return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg), tb, NETCONFA_MAX, devconf_ipv4_policy, extack); err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg), tb, NETCONFA_MAX, devconf_ipv4_policy, extack); if (err) return err; for (i = 0; i <= NETCONFA_MAX; i++) { if (!tb[i]) continue; switch (i) { case NETCONFA_IFINDEX: break; default: NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in netconf get request"); return -EINVAL; } } return 0; } static int inet_netconf_get_devconf(struct sk_buff *in_skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(in_skb->sk); struct nlattr *tb[NETCONFA_MAX+1]; struct sk_buff *skb; struct ipv4_devconf *devconf; struct in_device *in_dev; struct net_device *dev; int ifindex; int err; err = inet_netconf_valid_get_req(in_skb, nlh, tb, extack); if (err) goto errout; err = -EINVAL; if (!tb[NETCONFA_IFINDEX]) goto errout; ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]); switch (ifindex) { case NETCONFA_IFINDEX_ALL: devconf = net->ipv4.devconf_all; break; case NETCONFA_IFINDEX_DEFAULT: devconf = net->ipv4.devconf_dflt; break; default: dev = __dev_get_by_index(net, ifindex); if (!dev) goto errout; in_dev = __in_dev_get_rtnl(dev); if (!in_dev) goto errout; devconf = &in_dev->cnf; break; } err = -ENOBUFS; skb = nlmsg_new(inet_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL); if (!skb) goto errout; err = inet_netconf_fill_devconf(skb, ifindex, devconf, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, RTM_NEWNETCONF, 0, NETCONFA_ALL); if (err < 0) { /* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */ WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; } err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); errout: return err; } static int inet_netconf_dump_devconf(struct sk_buff *skb, struct netlink_callback *cb) { const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); int h, s_h; int idx, s_idx; struct net_device *dev; struct in_device *in_dev; struct hlist_head *head; if (cb->strict_check) { struct netlink_ext_ack *extack = cb->extack; struct netconfmsg *ncm; if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) { NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf dump request"); return -EINVAL; } if (nlmsg_attrlen(nlh, sizeof(*ncm))) { NL_SET_ERR_MSG(extack, "ipv4: Invalid data after header in netconf dump request"); return -EINVAL; } } s_h = cb->args[0]; s_idx = idx = cb->args[1]; for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { idx = 0; head = &net->dev_index_head[h]; rcu_read_lock(); cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^ net->dev_base_seq; hlist_for_each_entry_rcu(dev, head, index_hlist) { if (idx < s_idx) goto cont; in_dev = __in_dev_get_rcu(dev); if (!in_dev) goto cont; if (inet_netconf_fill_devconf(skb, dev->ifindex, &in_dev->cnf, NETLINK_CB(cb->skb).portid, nlh->nlmsg_seq, RTM_NEWNETCONF, NLM_F_MULTI, NETCONFA_ALL) < 0) { rcu_read_unlock(); goto done; } nl_dump_check_consistent(cb, nlmsg_hdr(skb)); cont: idx++; } rcu_read_unlock(); } if (h == NETDEV_HASHENTRIES) { if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL, net->ipv4.devconf_all, NETLINK_CB(cb->skb).portid, nlh->nlmsg_seq, RTM_NEWNETCONF, NLM_F_MULTI, NETCONFA_ALL) < 0) goto done; else h++; } if (h == NETDEV_HASHENTRIES + 1) { if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT, net->ipv4.devconf_dflt, NETLINK_CB(cb->skb).portid, nlh->nlmsg_seq, RTM_NEWNETCONF, NLM_F_MULTI, NETCONFA_ALL) < 0) goto done; else h++; } done: cb->args[0] = h; cb->args[1] = idx; return skb->len; } #ifdef CONFIG_SYSCTL static void devinet_copy_dflt_conf(struct net *net, int i) { struct net_device *dev; rcu_read_lock(); for_each_netdev_rcu(net, dev) { struct in_device *in_dev; in_dev = __in_dev_get_rcu(dev); if (in_dev && !test_bit(i, in_dev->cnf.state)) in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i]; } rcu_read_unlock(); } /* called with RTNL locked */ static void inet_forward_change(struct net *net) { struct net_device *dev; int on = IPV4_DEVCONF_ALL(net, FORWARDING); IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on; IPV4_DEVCONF_DFLT(net, FORWARDING) = on; inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_FORWARDING, NETCONFA_IFINDEX_ALL, net->ipv4.devconf_all); inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_FORWARDING, NETCONFA_IFINDEX_DEFAULT, net->ipv4.devconf_dflt); for_each_netdev(net, dev) { struct in_device *in_dev; if (on) dev_disable_lro(dev); in_dev = __in_dev_get_rtnl(dev); if (in_dev) { IN_DEV_CONF_SET(in_dev, FORWARDING, on); inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_FORWARDING, dev->ifindex, &in_dev->cnf); } } } static int devinet_conf_ifindex(struct net *net, struct ipv4_devconf *cnf) { if (cnf == net->ipv4.devconf_dflt) return NETCONFA_IFINDEX_DEFAULT; else if (cnf == net->ipv4.devconf_all) return NETCONFA_IFINDEX_ALL; else { struct in_device *idev = container_of(cnf, struct in_device, cnf); return idev->dev->ifindex; } } static int devinet_conf_proc(struct ctl_table *ctl, int write, void *buffer, size_t *lenp, loff_t *ppos) { int old_value = *(int *)ctl->data; int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); int new_value = *(int *)ctl->data; if (write) { struct ipv4_devconf *cnf = ctl->extra1; struct net *net = ctl->extra2; int i = (int *)ctl->data - cnf->data; int ifindex; set_bit(i, cnf->state); if (cnf == net->ipv4.devconf_dflt) devinet_copy_dflt_conf(net, i); if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1 || i == IPV4_DEVCONF_ROUTE_LOCALNET - 1) if ((new_value == 0) && (old_value != 0)) rt_cache_flush(net); if (i == IPV4_DEVCONF_BC_FORWARDING - 1 && new_value != old_value) rt_cache_flush(net); if (i == IPV4_DEVCONF_RP_FILTER - 1 && new_value != old_value) { ifindex = devinet_conf_ifindex(net, cnf); inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_RP_FILTER, ifindex, cnf); } if (i == IPV4_DEVCONF_PROXY_ARP - 1 && new_value != old_value) { ifindex = devinet_conf_ifindex(net, cnf); inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_PROXY_NEIGH, ifindex, cnf); } if (i == IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN - 1 && new_value != old_value) { ifindex = devinet_conf_ifindex(net, cnf); inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN, ifindex, cnf); } } return ret; } static int devinet_sysctl_forward(struct ctl_table *ctl, int write, void *buffer, size_t *lenp, loff_t *ppos) { int *valp = ctl->data; int val = *valp; loff_t pos = *ppos; struct net *net = ctl->extra2; int ret; if (write && !ns_capable(net->user_ns, CAP_NET_ADMIN)) return -EPERM; ret = proc_dointvec(ctl, write, buffer, lenp, ppos); if (write && *valp != val) { if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) { if (!rtnl_trylock()) { /* Restore the original values before restarting */ *valp = val; *ppos = pos; return restart_syscall(); } if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) { inet_forward_change(net); } else { struct ipv4_devconf *cnf = ctl->extra1; struct in_device *idev = container_of(cnf, struct in_device, cnf); if (*valp) dev_disable_lro(idev->dev); inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_FORWARDING, idev->dev->ifindex, cnf); } rtnl_unlock(); rt_cache_flush(net); } else inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_FORWARDING, NETCONFA_IFINDEX_DEFAULT, net->ipv4.devconf_dflt); } return ret; } static int ipv4_doint_and_flush(struct ctl_table *ctl, int write, void *buffer, size_t *lenp, loff_t *ppos) { int *valp = ctl->data; int val = *valp; int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); struct net *net = ctl->extra2; if (write && *valp != val) rt_cache_flush(net); return ret; } #define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \ { \ .procname = name, \ .data = ipv4_devconf.data + \ IPV4_DEVCONF_ ## attr - 1, \ .maxlen = sizeof(int), \ .mode = mval, \ .proc_handler = proc, \ .extra1 = &ipv4_devconf, \ } #define DEVINET_SYSCTL_RW_ENTRY(attr, name) \ DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc) #define DEVINET_SYSCTL_RO_ENTRY(attr, name) \ DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc) #define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \ DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc) #define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \ DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush) static struct devinet_sysctl_table { struct ctl_table_header *sysctl_header; struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX]; } devinet_sysctl = { .devinet_vars = { DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding", devinet_sysctl_forward), DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"), DEVINET_SYSCTL_RW_ENTRY(BC_FORWARDING, "bc_forwarding"), DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"), DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"), DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"), DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"), DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"), DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE, "accept_source_route"), DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"), DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"), DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"), DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"), DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"), DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"), DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"), DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"), DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"), DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"), DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"), DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"), DEVINET_SYSCTL_RW_ENTRY(ARP_EVICT_NOCARRIER, "arp_evict_nocarrier"), DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"), DEVINET_SYSCTL_RW_ENTRY(FORCE_IGMP_VERSION, "force_igmp_version"), DEVINET_SYSCTL_RW_ENTRY(IGMPV2_UNSOLICITED_REPORT_INTERVAL, "igmpv2_unsolicited_report_interval"), DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL, "igmpv3_unsolicited_report_interval"), DEVINET_SYSCTL_RW_ENTRY(IGNORE_ROUTES_WITH_LINKDOWN, "ignore_routes_with_linkdown"), DEVINET_SYSCTL_RW_ENTRY(DROP_GRATUITOUS_ARP, "drop_gratuitous_arp"), DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"), DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"), DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES, "promote_secondaries"), DEVINET_SYSCTL_FLUSHING_ENTRY(ROUTE_LOCALNET, "route_localnet"), DEVINET_SYSCTL_FLUSHING_ENTRY(DROP_UNICAST_IN_L2_MULTICAST, "drop_unicast_in_l2_multicast"), }, }; static int __devinet_sysctl_register(struct net *net, char *dev_name, int ifindex, struct ipv4_devconf *p) { int i; struct devinet_sysctl_table *t; char path[sizeof("net/ipv4/conf/") + IFNAMSIZ]; t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL_ACCOUNT); if (!t) goto out; for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) { t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf; t->devinet_vars[i].extra1 = p; t->devinet_vars[i].extra2 = net; } snprintf(path, sizeof(path), "net/ipv4/conf/%s", dev_name); t->sysctl_header = register_net_sysctl(net, path, t->devinet_vars); if (!t->sysctl_header) goto free; p->sysctl = t; inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL, ifindex, p); return 0; free: kfree(t); out: return -ENOMEM; } static void __devinet_sysctl_unregister(struct net *net, struct ipv4_devconf *cnf, int ifindex) { struct devinet_sysctl_table *t = cnf->sysctl; if (t) { cnf->sysctl = NULL; unregister_net_sysctl_table(t->sysctl_header); kfree(t); } inet_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL); } static int devinet_sysctl_register(struct in_device *idev) { int err; if (!sysctl_dev_name_is_allowed(idev->dev->name)) return -EINVAL; err = neigh_sysctl_register(idev->dev, idev->arp_parms, NULL); if (err) return err; err = __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name, idev->dev->ifindex, &idev->cnf); if (err) neigh_sysctl_unregister(idev->arp_parms); return err; } static void devinet_sysctl_unregister(struct in_device *idev) { struct net *net = dev_net(idev->dev); __devinet_sysctl_unregister(net, &idev->cnf, idev->dev->ifindex); neigh_sysctl_unregister(idev->arp_parms); } static struct ctl_table ctl_forward_entry[] = { { .procname = "ip_forward", .data = &ipv4_devconf.data[ IPV4_DEVCONF_FORWARDING - 1], .maxlen = sizeof(int), .mode = 0644, .proc_handler = devinet_sysctl_forward, .extra1 = &ipv4_devconf, .extra2 = &init_net, }, { }, }; #endif static __net_init int devinet_init_net(struct net *net) { int err; struct ipv4_devconf *all, *dflt; #ifdef CONFIG_SYSCTL struct ctl_table *tbl; struct ctl_table_header *forw_hdr; #endif err = -ENOMEM; all = kmemdup(&ipv4_devconf, sizeof(ipv4_devconf), GFP_KERNEL); if (!all) goto err_alloc_all; dflt = kmemdup(&ipv4_devconf_dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL); if (!dflt) goto err_alloc_dflt; #ifdef CONFIG_SYSCTL tbl = kmemdup(ctl_forward_entry, sizeof(ctl_forward_entry), GFP_KERNEL); if (!tbl) goto err_alloc_ctl; tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1]; tbl[0].extra1 = all; tbl[0].extra2 = net; #endif if (!net_eq(net, &init_net)) { switch (net_inherit_devconf()) { case 3: /* copy from the current netns */ memcpy(all, current->nsproxy->net_ns->ipv4.devconf_all, sizeof(ipv4_devconf)); memcpy(dflt, current->nsproxy->net_ns->ipv4.devconf_dflt, sizeof(ipv4_devconf_dflt)); break; case 0: case 1: /* copy from init_net */ memcpy(all, init_net.ipv4.devconf_all, sizeof(ipv4_devconf)); memcpy(dflt, init_net.ipv4.devconf_dflt, sizeof(ipv4_devconf_dflt)); break; case 2: /* use compiled values */ break; } } #ifdef CONFIG_SYSCTL err = __devinet_sysctl_register(net, "all", NETCONFA_IFINDEX_ALL, all); if (err < 0) goto err_reg_all; err = __devinet_sysctl_register(net, "default", NETCONFA_IFINDEX_DEFAULT, dflt); if (err < 0) goto err_reg_dflt; err = -ENOMEM; forw_hdr = register_net_sysctl_sz(net, "net/ipv4", tbl, ARRAY_SIZE(ctl_forward_entry)); if (!forw_hdr) goto err_reg_ctl; net->ipv4.forw_hdr = forw_hdr; #endif net->ipv4.devconf_all = all; net->ipv4.devconf_dflt = dflt; return 0; #ifdef CONFIG_SYSCTL err_reg_ctl: __devinet_sysctl_unregister(net, dflt, NETCONFA_IFINDEX_DEFAULT); err_reg_dflt: __devinet_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL); err_reg_all: kfree(tbl); err_alloc_ctl: #endif kfree(dflt); err_alloc_dflt: kfree(all); err_alloc_all: return err; } static __net_exit void devinet_exit_net(struct net *net) { #ifdef CONFIG_SYSCTL struct ctl_table *tbl; tbl = net->ipv4.forw_hdr->ctl_table_arg; unregister_net_sysctl_table(net->ipv4.forw_hdr); __devinet_sysctl_unregister(net, net->ipv4.devconf_dflt, NETCONFA_IFINDEX_DEFAULT); __devinet_sysctl_unregister(net, net->ipv4.devconf_all, NETCONFA_IFINDEX_ALL); kfree(tbl); #endif kfree(net->ipv4.devconf_dflt); kfree(net->ipv4.devconf_all); } static __net_initdata struct pernet_operations devinet_ops = { .init = devinet_init_net, .exit = devinet_exit_net, }; static struct rtnl_af_ops inet_af_ops __read_mostly = { .family = AF_INET, .fill_link_af = inet_fill_link_af, .get_link_af_size = inet_get_link_af_size, .validate_link_af = inet_validate_link_af, .set_link_af = inet_set_link_af, }; void __init devinet_init(void) { int i; for (i = 0; i < IN4_ADDR_HSIZE; i++) INIT_HLIST_HEAD(&inet_addr_lst[i]); register_pernet_subsys(&devinet_ops); register_netdevice_notifier(&ip_netdev_notifier); queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0); rtnl_af_register(&inet_af_ops); rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, 0); rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, 0); rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, 0); rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf, inet_netconf_dump_devconf, 0); }
linux-master
net/ipv4/devinet.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Implementation of the Transmission Control Protocol(TCP). * * IPv4 specific functions * * code split from: * linux/ipv4/tcp.c * linux/ipv4/tcp_input.c * linux/ipv4/tcp_output.c * * See tcp.c for author information */ /* * Changes: * David S. Miller : New socket lookup architecture. * This code is dedicated to John Dyson. * David S. Miller : Change semantics of established hash, * half is devoted to TIME_WAIT sockets * and the rest go in the other half. * Andi Kleen : Add support for syncookies and fixed * some bugs: ip options weren't passed to * the TCP layer, missed a check for an * ACK bit. * Andi Kleen : Implemented fast path mtu discovery. * Fixed many serious bugs in the * request_sock handling and moved * most of it into the af independent code. * Added tail drop and some other bugfixes. * Added new listen semantics. * Mike McLagan : Routing by source * Juan Jose Ciarlante: ip_dynaddr bits * Andi Kleen: various fixes. * Vitaly E. Lavrov : Transparent proxy revived after year * coma. * Andi Kleen : Fix new listen. * Andi Kleen : Fix accept error reporting. * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind * a single port at the same time. */ #define pr_fmt(fmt) "TCP: " fmt #include <linux/bottom_half.h> #include <linux/types.h> #include <linux/fcntl.h> #include <linux/module.h> #include <linux/random.h> #include <linux/cache.h> #include <linux/jhash.h> #include <linux/init.h> #include <linux/times.h> #include <linux/slab.h> #include <linux/sched.h> #include <net/net_namespace.h> #include <net/icmp.h> #include <net/inet_hashtables.h> #include <net/tcp.h> #include <net/transp_v6.h> #include <net/ipv6.h> #include <net/inet_common.h> #include <net/timewait_sock.h> #include <net/xfrm.h> #include <net/secure_seq.h> #include <net/busy_poll.h> #include <linux/inet.h> #include <linux/ipv6.h> #include <linux/stddef.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/inetdevice.h> #include <linux/btf_ids.h> #include <crypto/hash.h> #include <linux/scatterlist.h> #include <trace/events/tcp.h> #ifdef CONFIG_TCP_MD5SIG static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, __be32 daddr, __be32 saddr, const struct tcphdr *th); #endif struct inet_hashinfo tcp_hashinfo; EXPORT_SYMBOL(tcp_hashinfo); static DEFINE_PER_CPU(struct sock *, ipv4_tcp_sk); static u32 tcp_v4_init_seq(const struct sk_buff *skb) { return secure_tcp_seq(ip_hdr(skb)->daddr, ip_hdr(skb)->saddr, tcp_hdr(skb)->dest, tcp_hdr(skb)->source); } static u32 tcp_v4_init_ts_off(const struct net *net, const struct sk_buff *skb) { return secure_tcp_ts_off(net, ip_hdr(skb)->daddr, ip_hdr(skb)->saddr); } int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp) { int reuse = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_tw_reuse); const struct inet_timewait_sock *tw = inet_twsk(sktw); const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw); struct tcp_sock *tp = tcp_sk(sk); if (reuse == 2) { /* Still does not detect *everything* that goes through * lo, since we require a loopback src or dst address * or direct binding to 'lo' interface. */ bool loopback = false; if (tw->tw_bound_dev_if == LOOPBACK_IFINDEX) loopback = true; #if IS_ENABLED(CONFIG_IPV6) if (tw->tw_family == AF_INET6) { if (ipv6_addr_loopback(&tw->tw_v6_daddr) || ipv6_addr_v4mapped_loopback(&tw->tw_v6_daddr) || ipv6_addr_loopback(&tw->tw_v6_rcv_saddr) || ipv6_addr_v4mapped_loopback(&tw->tw_v6_rcv_saddr)) loopback = true; } else #endif { if (ipv4_is_loopback(tw->tw_daddr) || ipv4_is_loopback(tw->tw_rcv_saddr)) loopback = true; } if (!loopback) reuse = 0; } /* With PAWS, it is safe from the viewpoint of data integrity. Even without PAWS it is safe provided sequence spaces do not overlap i.e. at data rates <= 80Mbit/sec. Actually, the idea is close to VJ's one, only timestamp cache is held not per host, but per port pair and TW bucket is used as state holder. If TW bucket has been already destroyed we fall back to VJ's scheme and use initial timestamp retrieved from peer table. */ if (tcptw->tw_ts_recent_stamp && (!twp || (reuse && time_after32(ktime_get_seconds(), tcptw->tw_ts_recent_stamp)))) { /* In case of repair and re-using TIME-WAIT sockets we still * want to be sure that it is safe as above but honor the * sequence numbers and time stamps set as part of the repair * process. * * Without this check re-using a TIME-WAIT socket with TCP * repair would accumulate a -1 on the repair assigned * sequence number. The first time it is reused the sequence * is -1, the second time -2, etc. This fixes that issue * without appearing to create any others. */ if (likely(!tp->repair)) { u32 seq = tcptw->tw_snd_nxt + 65535 + 2; if (!seq) seq = 1; WRITE_ONCE(tp->write_seq, seq); tp->rx_opt.ts_recent = tcptw->tw_ts_recent; tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; } sock_hold(sktw); return 1; } return 0; } EXPORT_SYMBOL_GPL(tcp_twsk_unique); static int tcp_v4_pre_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { /* This check is replicated from tcp_v4_connect() and intended to * prevent BPF program called below from accessing bytes that are out * of the bound specified by user in addr_len. */ if (addr_len < sizeof(struct sockaddr_in)) return -EINVAL; sock_owned_by_me(sk); return BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr); } /* This will initiate an outgoing connection. */ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; struct inet_timewait_death_row *tcp_death_row; struct inet_sock *inet = inet_sk(sk); struct tcp_sock *tp = tcp_sk(sk); struct ip_options_rcu *inet_opt; struct net *net = sock_net(sk); __be16 orig_sport, orig_dport; __be32 daddr, nexthop; struct flowi4 *fl4; struct rtable *rt; int err; if (addr_len < sizeof(struct sockaddr_in)) return -EINVAL; if (usin->sin_family != AF_INET) return -EAFNOSUPPORT; nexthop = daddr = usin->sin_addr.s_addr; inet_opt = rcu_dereference_protected(inet->inet_opt, lockdep_sock_is_held(sk)); if (inet_opt && inet_opt->opt.srr) { if (!daddr) return -EINVAL; nexthop = inet_opt->opt.faddr; } orig_sport = inet->inet_sport; orig_dport = usin->sin_port; fl4 = &inet->cork.fl.u.ip4; rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, sk->sk_bound_dev_if, IPPROTO_TCP, orig_sport, orig_dport, sk); if (IS_ERR(rt)) { err = PTR_ERR(rt); if (err == -ENETUNREACH) IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); return err; } if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { ip_rt_put(rt); return -ENETUNREACH; } if (!inet_opt || !inet_opt->opt.srr) daddr = fl4->daddr; tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row; if (!inet->inet_saddr) { err = inet_bhash2_update_saddr(sk, &fl4->saddr, AF_INET); if (err) { ip_rt_put(rt); return err; } } else { sk_rcv_saddr_set(sk, inet->inet_saddr); } if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) { /* Reset inherited state */ tp->rx_opt.ts_recent = 0; tp->rx_opt.ts_recent_stamp = 0; if (likely(!tp->repair)) WRITE_ONCE(tp->write_seq, 0); } inet->inet_dport = usin->sin_port; sk_daddr_set(sk, daddr); inet_csk(sk)->icsk_ext_hdr_len = 0; if (inet_opt) inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT; /* Socket identity is still unknown (sport may be zero). * However we set state to SYN-SENT and not releasing socket * lock select source port, enter ourselves into the hash tables and * complete initialization after this. */ tcp_set_state(sk, TCP_SYN_SENT); err = inet_hash_connect(tcp_death_row, sk); if (err) goto failure; sk_set_txhash(sk); rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, inet->inet_sport, inet->inet_dport, sk); if (IS_ERR(rt)) { err = PTR_ERR(rt); rt = NULL; goto failure; } /* OK, now commit destination to socket. */ sk->sk_gso_type = SKB_GSO_TCPV4; sk_setup_caps(sk, &rt->dst); rt = NULL; if (likely(!tp->repair)) { if (!tp->write_seq) WRITE_ONCE(tp->write_seq, secure_tcp_seq(inet->inet_saddr, inet->inet_daddr, inet->inet_sport, usin->sin_port)); WRITE_ONCE(tp->tsoffset, secure_tcp_ts_off(net, inet->inet_saddr, inet->inet_daddr)); } atomic_set(&inet->inet_id, get_random_u16()); if (tcp_fastopen_defer_connect(sk, &err)) return err; if (err) goto failure; err = tcp_connect(sk); if (err) goto failure; return 0; failure: /* * This unhashes the socket and releases the local port, * if necessary. */ tcp_set_state(sk, TCP_CLOSE); inet_bhash2_reset_saddr(sk); ip_rt_put(rt); sk->sk_route_caps = 0; inet->inet_dport = 0; return err; } EXPORT_SYMBOL(tcp_v4_connect); /* * This routine reacts to ICMP_FRAG_NEEDED mtu indications as defined in RFC1191. * It can be called through tcp_release_cb() if socket was owned by user * at the time tcp_v4_err() was called to handle ICMP message. */ void tcp_v4_mtu_reduced(struct sock *sk) { struct inet_sock *inet = inet_sk(sk); struct dst_entry *dst; u32 mtu; if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) return; mtu = READ_ONCE(tcp_sk(sk)->mtu_info); dst = inet_csk_update_pmtu(sk, mtu); if (!dst) return; /* Something is about to be wrong... Remember soft error * for the case, if this connection will not able to recover. */ if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) WRITE_ONCE(sk->sk_err_soft, EMSGSIZE); mtu = dst_mtu(dst); if (inet->pmtudisc != IP_PMTUDISC_DONT && ip_sk_accept_pmtu(sk) && inet_csk(sk)->icsk_pmtu_cookie > mtu) { tcp_sync_mss(sk, mtu); /* Resend the TCP packet because it's * clear that the old packet has been * dropped. This is the new "fast" path mtu * discovery. */ tcp_simple_retransmit(sk); } /* else let the usual retransmit timer handle it */ } EXPORT_SYMBOL(tcp_v4_mtu_reduced); static void do_redirect(struct sk_buff *skb, struct sock *sk) { struct dst_entry *dst = __sk_dst_check(sk, 0); if (dst) dst->ops->redirect(dst, sk, skb); } /* handle ICMP messages on TCP_NEW_SYN_RECV request sockets */ void tcp_req_err(struct sock *sk, u32 seq, bool abort) { struct request_sock *req = inet_reqsk(sk); struct net *net = sock_net(sk); /* ICMPs are not backlogged, hence we cannot get * an established socket here. */ if (seq != tcp_rsk(req)->snt_isn) { __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); } else if (abort) { /* * Still in SYN_RECV, just remove it silently. * There is no good way to pass the error to the newly * created socket, and POSIX does not want network * errors returned from accept(). */ inet_csk_reqsk_queue_drop(req->rsk_listener, req); tcp_listendrop(req->rsk_listener); } reqsk_put(req); } EXPORT_SYMBOL(tcp_req_err); /* TCP-LD (RFC 6069) logic */ void tcp_ld_RTO_revert(struct sock *sk, u32 seq) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; s32 remaining; u32 delta_us; if (sock_owned_by_user(sk)) return; if (seq != tp->snd_una || !icsk->icsk_retransmits || !icsk->icsk_backoff) return; skb = tcp_rtx_queue_head(sk); if (WARN_ON_ONCE(!skb)) return; icsk->icsk_backoff--; icsk->icsk_rto = tp->srtt_us ? __tcp_set_rto(tp) : TCP_TIMEOUT_INIT; icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX); tcp_mstamp_refresh(tp); delta_us = (u32)(tp->tcp_mstamp - tcp_skb_timestamp_us(skb)); remaining = icsk->icsk_rto - usecs_to_jiffies(delta_us); if (remaining > 0) { inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, remaining, TCP_RTO_MAX); } else { /* RTO revert clocked out retransmission. * Will retransmit now. */ tcp_retransmit_timer(sk); } } EXPORT_SYMBOL(tcp_ld_RTO_revert); /* * This routine is called by the ICMP module when it gets some * sort of error condition. If err < 0 then the socket should * be closed and the error returned to the user. If err > 0 * it's just the icmp type << 8 | icmp code. After adjustment * header points to the first 8 bytes of the tcp header. We need * to find the appropriate port. * * The locking strategy used here is very "optimistic". When * someone else accesses the socket the ICMP is just dropped * and for some paths there is no check at all. * A more general error queue to queue errors for later handling * is probably better. * */ int tcp_v4_err(struct sk_buff *skb, u32 info) { const struct iphdr *iph = (const struct iphdr *)skb->data; struct tcphdr *th = (struct tcphdr *)(skb->data + (iph->ihl << 2)); struct tcp_sock *tp; const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; struct sock *sk; struct request_sock *fastopen; u32 seq, snd_una; int err; struct net *net = dev_net(skb->dev); sk = __inet_lookup_established(net, net->ipv4.tcp_death_row.hashinfo, iph->daddr, th->dest, iph->saddr, ntohs(th->source), inet_iif(skb), 0); if (!sk) { __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); return -ENOENT; } if (sk->sk_state == TCP_TIME_WAIT) { inet_twsk_put(inet_twsk(sk)); return 0; } seq = ntohl(th->seq); if (sk->sk_state == TCP_NEW_SYN_RECV) { tcp_req_err(sk, seq, type == ICMP_PARAMETERPROB || type == ICMP_TIME_EXCEEDED || (type == ICMP_DEST_UNREACH && (code == ICMP_NET_UNREACH || code == ICMP_HOST_UNREACH))); return 0; } bh_lock_sock(sk); /* If too many ICMPs get dropped on busy * servers this needs to be solved differently. * We do take care of PMTU discovery (RFC1191) special case : * we can receive locally generated ICMP messages while socket is held. */ if (sock_owned_by_user(sk)) { if (!(type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)) __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); } if (sk->sk_state == TCP_CLOSE) goto out; if (static_branch_unlikely(&ip4_min_ttl)) { /* min_ttl can be changed concurrently from do_ip_setsockopt() */ if (unlikely(iph->ttl < READ_ONCE(inet_sk(sk)->min_ttl))) { __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); goto out; } } tp = tcp_sk(sk); /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ fastopen = rcu_dereference(tp->fastopen_rsk); snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; if (sk->sk_state != TCP_LISTEN && !between(seq, snd_una, tp->snd_nxt)) { __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); goto out; } switch (type) { case ICMP_REDIRECT: if (!sock_owned_by_user(sk)) do_redirect(skb, sk); goto out; case ICMP_SOURCE_QUENCH: /* Just silently ignore these. */ goto out; case ICMP_PARAMETERPROB: err = EPROTO; break; case ICMP_DEST_UNREACH: if (code > NR_ICMP_UNREACH) goto out; if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ /* We are not interested in TCP_LISTEN and open_requests * (SYN-ACKs send out by Linux are always <576bytes so * they should go through unfragmented). */ if (sk->sk_state == TCP_LISTEN) goto out; WRITE_ONCE(tp->mtu_info, info); if (!sock_owned_by_user(sk)) { tcp_v4_mtu_reduced(sk); } else { if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &sk->sk_tsq_flags)) sock_hold(sk); } goto out; } err = icmp_err_convert[code].errno; /* check if this ICMP message allows revert of backoff. * (see RFC 6069) */ if (!fastopen && (code == ICMP_NET_UNREACH || code == ICMP_HOST_UNREACH)) tcp_ld_RTO_revert(sk, seq); break; case ICMP_TIME_EXCEEDED: err = EHOSTUNREACH; break; default: goto out; } switch (sk->sk_state) { case TCP_SYN_SENT: case TCP_SYN_RECV: /* Only in fast or simultaneous open. If a fast open socket is * already accepted it is treated as a connected one below. */ if (fastopen && !fastopen->sk) break; ip_icmp_error(sk, skb, err, th->dest, info, (u8 *)th); if (!sock_owned_by_user(sk)) { WRITE_ONCE(sk->sk_err, err); sk_error_report(sk); tcp_done(sk); } else { WRITE_ONCE(sk->sk_err_soft, err); } goto out; } /* If we've already connected we will keep trying * until we time out, or the user gives up. * * rfc1122 4.2.3.9 allows to consider as hard errors * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, * but it is obsoleted by pmtu discovery). * * Note, that in modern internet, where routing is unreliable * and in each dark corner broken firewalls sit, sending random * errors ordered by their masters even this two messages finally lose * their original sense (even Linux sends invalid PORT_UNREACHs) * * Now we are in compliance with RFCs. * --ANK (980905) */ if (!sock_owned_by_user(sk) && inet_test_bit(RECVERR, sk)) { WRITE_ONCE(sk->sk_err, err); sk_error_report(sk); } else { /* Only an error on timeout */ WRITE_ONCE(sk->sk_err_soft, err); } out: bh_unlock_sock(sk); sock_put(sk); return 0; } void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr) { struct tcphdr *th = tcp_hdr(skb); th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0); skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = offsetof(struct tcphdr, check); } /* This routine computes an IPv4 TCP checksum. */ void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb) { const struct inet_sock *inet = inet_sk(sk); __tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr); } EXPORT_SYMBOL(tcp_v4_send_check); /* * This routine will send an RST to the other tcp. * * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) * for reset. * Answer: if a packet caused RST, it is not for a socket * existing in our system, if it is matched to a socket, * it is just duplicate segment or bug in other side's TCP. * So that we build reply only basing on parameters * arrived with segment. * Exception: precedence violation. We do not implement it in any case. */ #ifdef CONFIG_TCP_MD5SIG #define OPTION_BYTES TCPOLEN_MD5SIG_ALIGNED #else #define OPTION_BYTES sizeof(__be32) #endif static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) { const struct tcphdr *th = tcp_hdr(skb); struct { struct tcphdr th; __be32 opt[OPTION_BYTES / sizeof(__be32)]; } rep; struct ip_reply_arg arg; #ifdef CONFIG_TCP_MD5SIG struct tcp_md5sig_key *key = NULL; const __u8 *hash_location = NULL; unsigned char newhash[16]; int genhash; struct sock *sk1 = NULL; #endif u64 transmit_time = 0; struct sock *ctl_sk; struct net *net; u32 txhash = 0; /* Never send a reset in response to a reset. */ if (th->rst) return; /* If sk not NULL, it means we did a successful lookup and incoming * route had to be correct. prequeue might have dropped our dst. */ if (!sk && skb_rtable(skb)->rt_type != RTN_LOCAL) return; /* Swap the send and the receive. */ memset(&rep, 0, sizeof(rep)); rep.th.dest = th->source; rep.th.source = th->dest; rep.th.doff = sizeof(struct tcphdr) / 4; rep.th.rst = 1; if (th->ack) { rep.th.seq = th->ack_seq; } else { rep.th.ack = 1; rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin + skb->len - (th->doff << 2)); } memset(&arg, 0, sizeof(arg)); arg.iov[0].iov_base = (unsigned char *)&rep; arg.iov[0].iov_len = sizeof(rep.th); net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); #ifdef CONFIG_TCP_MD5SIG rcu_read_lock(); hash_location = tcp_parse_md5sig_option(th); if (sk && sk_fullsock(sk)) { const union tcp_md5_addr *addr; int l3index; /* sdif set, means packet ingressed via a device * in an L3 domain and inet_iif is set to it. */ l3index = tcp_v4_sdif(skb) ? inet_iif(skb) : 0; addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; key = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); } else if (hash_location) { const union tcp_md5_addr *addr; int sdif = tcp_v4_sdif(skb); int dif = inet_iif(skb); int l3index; /* * active side is lost. Try to find listening socket through * source port, and then find md5 key through listening socket. * we are not loose security here: * Incoming packet is checked with md5 hash with finding key, * no RST generated if md5 hash doesn't match. */ sk1 = __inet_lookup_listener(net, net->ipv4.tcp_death_row.hashinfo, NULL, 0, ip_hdr(skb)->saddr, th->source, ip_hdr(skb)->daddr, ntohs(th->source), dif, sdif); /* don't send rst if it can't find key */ if (!sk1) goto out; /* sdif set, means packet ingressed via a device * in an L3 domain and dif is set to it. */ l3index = sdif ? dif : 0; addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; key = tcp_md5_do_lookup(sk1, l3index, addr, AF_INET); if (!key) goto out; genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) goto out; } if (key) { rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); /* Update length and the length the header thinks exists */ arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; rep.th.doff = arg.iov[0].iov_len / 4; tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1], key, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, &rep.th); } #endif /* Can't co-exist with TCPMD5, hence check rep.opt[0] */ if (rep.opt[0] == 0) { __be32 mrst = mptcp_reset_option(skb); if (mrst) { rep.opt[0] = mrst; arg.iov[0].iov_len += sizeof(mrst); rep.th.doff = arg.iov[0].iov_len / 4; } } arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, ip_hdr(skb)->saddr, /* XXX */ arg.iov[0].iov_len, IPPROTO_TCP, 0); arg.csumoffset = offsetof(struct tcphdr, check) / 2; arg.flags = (sk && inet_sk_transparent(sk)) ? IP_REPLY_ARG_NOSRCCHECK : 0; /* When socket is gone, all binding information is lost. * routing might fail in this case. No choice here, if we choose to force * input interface, we will misroute in case of asymmetric route. */ if (sk) { arg.bound_dev_if = sk->sk_bound_dev_if; if (sk_fullsock(sk)) trace_tcp_send_reset(sk, skb); } BUILD_BUG_ON(offsetof(struct sock, sk_bound_dev_if) != offsetof(struct inet_timewait_sock, tw_bound_dev_if)); arg.tos = ip_hdr(skb)->tos; arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL); local_bh_disable(); ctl_sk = this_cpu_read(ipv4_tcp_sk); sock_net_set(ctl_sk, net); if (sk) { ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ? inet_twsk(sk)->tw_mark : sk->sk_mark; ctl_sk->sk_priority = (sk->sk_state == TCP_TIME_WAIT) ? inet_twsk(sk)->tw_priority : sk->sk_priority; transmit_time = tcp_transmit_time(sk); xfrm_sk_clone_policy(ctl_sk, sk); txhash = (sk->sk_state == TCP_TIME_WAIT) ? inet_twsk(sk)->tw_txhash : sk->sk_txhash; } else { ctl_sk->sk_mark = 0; ctl_sk->sk_priority = 0; } ip_send_unicast_reply(ctl_sk, skb, &TCP_SKB_CB(skb)->header.h4.opt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, &arg, arg.iov[0].iov_len, transmit_time, txhash); xfrm_sk_free_policy(ctl_sk); sock_net_set(ctl_sk, &init_net); __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); __TCP_INC_STATS(net, TCP_MIB_OUTRSTS); local_bh_enable(); #ifdef CONFIG_TCP_MD5SIG out: rcu_read_unlock(); #endif } /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states outside socket context is ugly, certainly. What can I do? */ static void tcp_v4_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, struct tcp_md5sig_key *key, int reply_flags, u8 tos, u32 txhash) { const struct tcphdr *th = tcp_hdr(skb); struct { struct tcphdr th; __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2) #ifdef CONFIG_TCP_MD5SIG + (TCPOLEN_MD5SIG_ALIGNED >> 2) #endif ]; } rep; struct net *net = sock_net(sk); struct ip_reply_arg arg; struct sock *ctl_sk; u64 transmit_time; memset(&rep.th, 0, sizeof(struct tcphdr)); memset(&arg, 0, sizeof(arg)); arg.iov[0].iov_base = (unsigned char *)&rep; arg.iov[0].iov_len = sizeof(rep.th); if (tsecr) { rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); rep.opt[1] = htonl(tsval); rep.opt[2] = htonl(tsecr); arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED; } /* Swap the send and the receive. */ rep.th.dest = th->source; rep.th.source = th->dest; rep.th.doff = arg.iov[0].iov_len / 4; rep.th.seq = htonl(seq); rep.th.ack_seq = htonl(ack); rep.th.ack = 1; rep.th.window = htons(win); #ifdef CONFIG_TCP_MD5SIG if (key) { int offset = (tsecr) ? 3 : 0; rep.opt[offset++] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; rep.th.doff = arg.iov[0].iov_len/4; tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[offset], key, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, &rep.th); } #endif arg.flags = reply_flags; arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, ip_hdr(skb)->saddr, /* XXX */ arg.iov[0].iov_len, IPPROTO_TCP, 0); arg.csumoffset = offsetof(struct tcphdr, check) / 2; if (oif) arg.bound_dev_if = oif; arg.tos = tos; arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL); local_bh_disable(); ctl_sk = this_cpu_read(ipv4_tcp_sk); sock_net_set(ctl_sk, net); ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ? inet_twsk(sk)->tw_mark : READ_ONCE(sk->sk_mark); ctl_sk->sk_priority = (sk->sk_state == TCP_TIME_WAIT) ? inet_twsk(sk)->tw_priority : READ_ONCE(sk->sk_priority); transmit_time = tcp_transmit_time(sk); ip_send_unicast_reply(ctl_sk, skb, &TCP_SKB_CB(skb)->header.h4.opt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, &arg, arg.iov[0].iov_len, transmit_time, txhash); sock_net_set(ctl_sk, &init_net); __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); local_bh_enable(); } static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) { struct inet_timewait_sock *tw = inet_twsk(sk); struct tcp_timewait_sock *tcptw = tcp_twsk(sk); tcp_v4_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, tcp_time_stamp_raw() + tcptw->tw_ts_offset, tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0, tw->tw_tos, tw->tw_txhash ); inet_twsk_put(tw); } static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, struct request_sock *req) { const union tcp_md5_addr *addr; int l3index; /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV * sk->sk_state == TCP_SYN_RECV -> for Fast Open. */ u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt; /* RFC 7323 2.3 * The window field (SEG.WND) of every outgoing segment, with the * exception of <SYN> segments, MUST be right-shifted by * Rcv.Wind.Shift bits: */ addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; l3index = tcp_v4_sdif(skb) ? inet_iif(skb) : 0; tcp_v4_send_ack(sk, skb, seq, tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, tcp_time_stamp_raw() + tcp_rsk(req)->ts_off, READ_ONCE(req->ts_recent), 0, tcp_md5_do_lookup(sk, l3index, addr, AF_INET), inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, ip_hdr(skb)->tos, READ_ONCE(tcp_rsk(req)->txhash)); } /* * Send a SYN-ACK after having received a SYN. * This still operates on a request_sock only, not on a big * socket. */ static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst, struct flowi *fl, struct request_sock *req, struct tcp_fastopen_cookie *foc, enum tcp_synack_type synack_type, struct sk_buff *syn_skb) { const struct inet_request_sock *ireq = inet_rsk(req); struct flowi4 fl4; int err = -1; struct sk_buff *skb; u8 tos; /* First, grab a route. */ if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL) return -1; skb = tcp_make_synack(sk, dst, req, foc, synack_type, syn_skb); if (skb) { __tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr); tos = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reflect_tos) ? (tcp_rsk(req)->syn_tos & ~INET_ECN_MASK) | (inet_sk(sk)->tos & INET_ECN_MASK) : inet_sk(sk)->tos; if (!INET_ECN_is_capable(tos) && tcp_bpf_ca_needs_ecn((struct sock *)req)) tos |= INET_ECN_ECT_0; rcu_read_lock(); err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, ireq->ir_rmt_addr, rcu_dereference(ireq->ireq_opt), tos); rcu_read_unlock(); err = net_xmit_eval(err); } return err; } /* * IPv4 request_sock destructor. */ static void tcp_v4_reqsk_destructor(struct request_sock *req) { kfree(rcu_dereference_protected(inet_rsk(req)->ireq_opt, 1)); } #ifdef CONFIG_TCP_MD5SIG /* * RFC2385 MD5 checksumming requires a mapping of * IP address->MD5 Key. * We need to maintain these in the sk structure. */ DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_md5_needed, HZ); EXPORT_SYMBOL(tcp_md5_needed); static bool better_md5_match(struct tcp_md5sig_key *old, struct tcp_md5sig_key *new) { if (!old) return true; /* l3index always overrides non-l3index */ if (old->l3index && new->l3index == 0) return false; if (old->l3index == 0 && new->l3index) return true; return old->prefixlen < new->prefixlen; } /* Find the Key structure for an address. */ struct tcp_md5sig_key *__tcp_md5_do_lookup(const struct sock *sk, int l3index, const union tcp_md5_addr *addr, int family) { const struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *key; const struct tcp_md5sig_info *md5sig; __be32 mask; struct tcp_md5sig_key *best_match = NULL; bool match; /* caller either holds rcu_read_lock() or socket lock */ md5sig = rcu_dereference_check(tp->md5sig_info, lockdep_sock_is_held(sk)); if (!md5sig) return NULL; hlist_for_each_entry_rcu(key, &md5sig->head, node, lockdep_sock_is_held(sk)) { if (key->family != family) continue; if (key->flags & TCP_MD5SIG_FLAG_IFINDEX && key->l3index != l3index) continue; if (family == AF_INET) { mask = inet_make_mask(key->prefixlen); match = (key->addr.a4.s_addr & mask) == (addr->a4.s_addr & mask); #if IS_ENABLED(CONFIG_IPV6) } else if (family == AF_INET6) { match = ipv6_prefix_equal(&key->addr.a6, &addr->a6, key->prefixlen); #endif } else { match = false; } if (match && better_md5_match(best_match, key)) best_match = key; } return best_match; } EXPORT_SYMBOL(__tcp_md5_do_lookup); static struct tcp_md5sig_key *tcp_md5_do_lookup_exact(const struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags) { const struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *key; unsigned int size = sizeof(struct in_addr); const struct tcp_md5sig_info *md5sig; /* caller either holds rcu_read_lock() or socket lock */ md5sig = rcu_dereference_check(tp->md5sig_info, lockdep_sock_is_held(sk)); if (!md5sig) return NULL; #if IS_ENABLED(CONFIG_IPV6) if (family == AF_INET6) size = sizeof(struct in6_addr); #endif hlist_for_each_entry_rcu(key, &md5sig->head, node, lockdep_sock_is_held(sk)) { if (key->family != family) continue; if ((key->flags & TCP_MD5SIG_FLAG_IFINDEX) != (flags & TCP_MD5SIG_FLAG_IFINDEX)) continue; if (key->l3index != l3index) continue; if (!memcmp(&key->addr, addr, size) && key->prefixlen == prefixlen) return key; } return NULL; } struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, const struct sock *addr_sk) { const union tcp_md5_addr *addr; int l3index; l3index = l3mdev_master_ifindex_by_index(sock_net(sk), addr_sk->sk_bound_dev_if); addr = (const union tcp_md5_addr *)&addr_sk->sk_daddr; return tcp_md5_do_lookup(sk, l3index, addr, AF_INET); } EXPORT_SYMBOL(tcp_v4_md5_lookup); static int tcp_md5sig_info_add(struct sock *sk, gfp_t gfp) { struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_info *md5sig; md5sig = kmalloc(sizeof(*md5sig), gfp); if (!md5sig) return -ENOMEM; sk_gso_disable(sk); INIT_HLIST_HEAD(&md5sig->head); rcu_assign_pointer(tp->md5sig_info, md5sig); return 0; } /* This can be called on a newly created socket, from other files */ static int __tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags, const u8 *newkey, u8 newkeylen, gfp_t gfp) { /* Add Key to the list */ struct tcp_md5sig_key *key; struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_info *md5sig; key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen, l3index, flags); if (key) { /* Pre-existing entry - just update that one. * Note that the key might be used concurrently. * data_race() is telling kcsan that we do not care of * key mismatches, since changing MD5 key on live flows * can lead to packet drops. */ data_race(memcpy(key->key, newkey, newkeylen)); /* Pairs with READ_ONCE() in tcp_md5_hash_key(). * Also note that a reader could catch new key->keylen value * but old key->key[], this is the reason we use __GFP_ZERO * at sock_kmalloc() time below these lines. */ WRITE_ONCE(key->keylen, newkeylen); return 0; } md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); key = sock_kmalloc(sk, sizeof(*key), gfp | __GFP_ZERO); if (!key) return -ENOMEM; if (!tcp_alloc_md5sig_pool()) { sock_kfree_s(sk, key, sizeof(*key)); return -ENOMEM; } memcpy(key->key, newkey, newkeylen); key->keylen = newkeylen; key->family = family; key->prefixlen = prefixlen; key->l3index = l3index; key->flags = flags; memcpy(&key->addr, addr, (IS_ENABLED(CONFIG_IPV6) && family == AF_INET6) ? sizeof(struct in6_addr) : sizeof(struct in_addr)); hlist_add_head_rcu(&key->node, &md5sig->head); return 0; } int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags, const u8 *newkey, u8 newkeylen) { struct tcp_sock *tp = tcp_sk(sk); if (!rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk))) { if (tcp_md5sig_info_add(sk, GFP_KERNEL)) return -ENOMEM; if (!static_branch_inc(&tcp_md5_needed.key)) { struct tcp_md5sig_info *md5sig; md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); rcu_assign_pointer(tp->md5sig_info, NULL); kfree_rcu(md5sig, rcu); return -EUSERS; } } return __tcp_md5_do_add(sk, addr, family, prefixlen, l3index, flags, newkey, newkeylen, GFP_KERNEL); } EXPORT_SYMBOL(tcp_md5_do_add); int tcp_md5_key_copy(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, struct tcp_md5sig_key *key) { struct tcp_sock *tp = tcp_sk(sk); if (!rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk))) { if (tcp_md5sig_info_add(sk, sk_gfp_mask(sk, GFP_ATOMIC))) return -ENOMEM; if (!static_key_fast_inc_not_disabled(&tcp_md5_needed.key.key)) { struct tcp_md5sig_info *md5sig; md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); net_warn_ratelimited("Too many TCP-MD5 keys in the system\n"); rcu_assign_pointer(tp->md5sig_info, NULL); kfree_rcu(md5sig, rcu); return -EUSERS; } } return __tcp_md5_do_add(sk, addr, family, prefixlen, l3index, key->flags, key->key, key->keylen, sk_gfp_mask(sk, GFP_ATOMIC)); } EXPORT_SYMBOL(tcp_md5_key_copy); int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags) { struct tcp_md5sig_key *key; key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen, l3index, flags); if (!key) return -ENOENT; hlist_del_rcu(&key->node); atomic_sub(sizeof(*key), &sk->sk_omem_alloc); kfree_rcu(key, rcu); return 0; } EXPORT_SYMBOL(tcp_md5_do_del); static void tcp_clear_md5_list(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *key; struct hlist_node *n; struct tcp_md5sig_info *md5sig; md5sig = rcu_dereference_protected(tp->md5sig_info, 1); hlist_for_each_entry_safe(key, n, &md5sig->head, node) { hlist_del_rcu(&key->node); atomic_sub(sizeof(*key), &sk->sk_omem_alloc); kfree_rcu(key, rcu); } } static int tcp_v4_parse_md5_keys(struct sock *sk, int optname, sockptr_t optval, int optlen) { struct tcp_md5sig cmd; struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr; const union tcp_md5_addr *addr; u8 prefixlen = 32; int l3index = 0; u8 flags; if (optlen < sizeof(cmd)) return -EINVAL; if (copy_from_sockptr(&cmd, optval, sizeof(cmd))) return -EFAULT; if (sin->sin_family != AF_INET) return -EINVAL; flags = cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX; if (optname == TCP_MD5SIG_EXT && cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) { prefixlen = cmd.tcpm_prefixlen; if (prefixlen > 32) return -EINVAL; } if (optname == TCP_MD5SIG_EXT && cmd.tcpm_ifindex && cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX) { struct net_device *dev; rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(sk), cmd.tcpm_ifindex); if (dev && netif_is_l3_master(dev)) l3index = dev->ifindex; rcu_read_unlock(); /* ok to reference set/not set outside of rcu; * right now device MUST be an L3 master */ if (!dev || !l3index) return -EINVAL; } addr = (union tcp_md5_addr *)&sin->sin_addr.s_addr; if (!cmd.tcpm_keylen) return tcp_md5_do_del(sk, addr, AF_INET, prefixlen, l3index, flags); if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) return -EINVAL; return tcp_md5_do_add(sk, addr, AF_INET, prefixlen, l3index, flags, cmd.tcpm_key, cmd.tcpm_keylen); } static int tcp_v4_md5_hash_headers(struct tcp_md5sig_pool *hp, __be32 daddr, __be32 saddr, const struct tcphdr *th, int nbytes) { struct tcp4_pseudohdr *bp; struct scatterlist sg; struct tcphdr *_th; bp = hp->scratch; bp->saddr = saddr; bp->daddr = daddr; bp->pad = 0; bp->protocol = IPPROTO_TCP; bp->len = cpu_to_be16(nbytes); _th = (struct tcphdr *)(bp + 1); memcpy(_th, th, sizeof(*th)); _th->check = 0; sg_init_one(&sg, bp, sizeof(*bp) + sizeof(*th)); ahash_request_set_crypt(hp->md5_req, &sg, NULL, sizeof(*bp) + sizeof(*th)); return crypto_ahash_update(hp->md5_req); } static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, __be32 daddr, __be32 saddr, const struct tcphdr *th) { struct tcp_md5sig_pool *hp; struct ahash_request *req; hp = tcp_get_md5sig_pool(); if (!hp) goto clear_hash_noput; req = hp->md5_req; if (crypto_ahash_init(req)) goto clear_hash; if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, th->doff << 2)) goto clear_hash; if (tcp_md5_hash_key(hp, key)) goto clear_hash; ahash_request_set_crypt(req, NULL, md5_hash, 0); if (crypto_ahash_final(req)) goto clear_hash; tcp_put_md5sig_pool(); return 0; clear_hash: tcp_put_md5sig_pool(); clear_hash_noput: memset(md5_hash, 0, 16); return 1; } int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key, const struct sock *sk, const struct sk_buff *skb) { struct tcp_md5sig_pool *hp; struct ahash_request *req; const struct tcphdr *th = tcp_hdr(skb); __be32 saddr, daddr; if (sk) { /* valid for establish/request sockets */ saddr = sk->sk_rcv_saddr; daddr = sk->sk_daddr; } else { const struct iphdr *iph = ip_hdr(skb); saddr = iph->saddr; daddr = iph->daddr; } hp = tcp_get_md5sig_pool(); if (!hp) goto clear_hash_noput; req = hp->md5_req; if (crypto_ahash_init(req)) goto clear_hash; if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, skb->len)) goto clear_hash; if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) goto clear_hash; if (tcp_md5_hash_key(hp, key)) goto clear_hash; ahash_request_set_crypt(req, NULL, md5_hash, 0); if (crypto_ahash_final(req)) goto clear_hash; tcp_put_md5sig_pool(); return 0; clear_hash: tcp_put_md5sig_pool(); clear_hash_noput: memset(md5_hash, 0, 16); return 1; } EXPORT_SYMBOL(tcp_v4_md5_hash_skb); #endif static void tcp_v4_init_req(struct request_sock *req, const struct sock *sk_listener, struct sk_buff *skb) { struct inet_request_sock *ireq = inet_rsk(req); struct net *net = sock_net(sk_listener); sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); RCU_INIT_POINTER(ireq->ireq_opt, tcp_v4_save_options(net, skb)); } static struct dst_entry *tcp_v4_route_req(const struct sock *sk, struct sk_buff *skb, struct flowi *fl, struct request_sock *req) { tcp_v4_init_req(req, sk, skb); if (security_inet_conn_request(sk, skb, req)) return NULL; return inet_csk_route_req(sk, &fl->u.ip4, req); } struct request_sock_ops tcp_request_sock_ops __read_mostly = { .family = PF_INET, .obj_size = sizeof(struct tcp_request_sock), .rtx_syn_ack = tcp_rtx_synack, .send_ack = tcp_v4_reqsk_send_ack, .destructor = tcp_v4_reqsk_destructor, .send_reset = tcp_v4_send_reset, .syn_ack_timeout = tcp_syn_ack_timeout, }; const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { .mss_clamp = TCP_MSS_DEFAULT, #ifdef CONFIG_TCP_MD5SIG .req_md5_lookup = tcp_v4_md5_lookup, .calc_md5_hash = tcp_v4_md5_hash_skb, #endif #ifdef CONFIG_SYN_COOKIES .cookie_init_seq = cookie_v4_init_sequence, #endif .route_req = tcp_v4_route_req, .init_seq = tcp_v4_init_seq, .init_ts_off = tcp_v4_init_ts_off, .send_synack = tcp_v4_send_synack, }; int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) { /* Never answer to SYNs send to broadcast or multicast */ if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) goto drop; return tcp_conn_request(&tcp_request_sock_ops, &tcp_request_sock_ipv4_ops, sk, skb); drop: tcp_listendrop(sk); return 0; } EXPORT_SYMBOL(tcp_v4_conn_request); /* * The three way handshake has completed - we got a valid synack - * now create the new socket. */ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct dst_entry *dst, struct request_sock *req_unhash, bool *own_req) { struct inet_request_sock *ireq; bool found_dup_sk = false; struct inet_sock *newinet; struct tcp_sock *newtp; struct sock *newsk; #ifdef CONFIG_TCP_MD5SIG const union tcp_md5_addr *addr; struct tcp_md5sig_key *key; int l3index; #endif struct ip_options_rcu *inet_opt; if (sk_acceptq_is_full(sk)) goto exit_overflow; newsk = tcp_create_openreq_child(sk, req, skb); if (!newsk) goto exit_nonewsk; newsk->sk_gso_type = SKB_GSO_TCPV4; inet_sk_rx_dst_set(newsk, skb); newtp = tcp_sk(newsk); newinet = inet_sk(newsk); ireq = inet_rsk(req); sk_daddr_set(newsk, ireq->ir_rmt_addr); sk_rcv_saddr_set(newsk, ireq->ir_loc_addr); newsk->sk_bound_dev_if = ireq->ir_iif; newinet->inet_saddr = ireq->ir_loc_addr; inet_opt = rcu_dereference(ireq->ireq_opt); RCU_INIT_POINTER(newinet->inet_opt, inet_opt); newinet->mc_index = inet_iif(skb); newinet->mc_ttl = ip_hdr(skb)->ttl; newinet->rcv_tos = ip_hdr(skb)->tos; inet_csk(newsk)->icsk_ext_hdr_len = 0; if (inet_opt) inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen; atomic_set(&newinet->inet_id, get_random_u16()); /* Set ToS of the new socket based upon the value of incoming SYN. * ECT bits are set later in tcp_init_transfer(). */ if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reflect_tos)) newinet->tos = tcp_rsk(req)->syn_tos & ~INET_ECN_MASK; if (!dst) { dst = inet_csk_route_child_sock(sk, newsk, req); if (!dst) goto put_and_exit; } else { /* syncookie case : see end of cookie_v4_check() */ } sk_setup_caps(newsk, dst); tcp_ca_openreq_child(newsk, dst); tcp_sync_mss(newsk, dst_mtu(dst)); newtp->advmss = tcp_mss_clamp(tcp_sk(sk), dst_metric_advmss(dst)); tcp_initialize_rcv_mss(newsk); #ifdef CONFIG_TCP_MD5SIG l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif); /* Copy over the MD5 key from the original socket */ addr = (union tcp_md5_addr *)&newinet->inet_daddr; key = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); if (key) { if (tcp_md5_key_copy(newsk, addr, AF_INET, 32, l3index, key)) goto put_and_exit; sk_gso_disable(newsk); } #endif if (__inet_inherit_port(sk, newsk) < 0) goto put_and_exit; *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash), &found_dup_sk); if (likely(*own_req)) { tcp_move_syn(newtp, req); ireq->ireq_opt = NULL; } else { newinet->inet_opt = NULL; if (!req_unhash && found_dup_sk) { /* This code path should only be executed in the * syncookie case only */ bh_unlock_sock(newsk); sock_put(newsk); newsk = NULL; } } return newsk; exit_overflow: NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); exit_nonewsk: dst_release(dst); exit: tcp_listendrop(sk); return NULL; put_and_exit: newinet->inet_opt = NULL; inet_csk_prepare_forced_close(newsk); tcp_done(newsk); goto exit; } EXPORT_SYMBOL(tcp_v4_syn_recv_sock); static struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb) { #ifdef CONFIG_SYN_COOKIES const struct tcphdr *th = tcp_hdr(skb); if (!th->syn) sk = cookie_v4_check(sk, skb); #endif return sk; } u16 tcp_v4_get_syncookie(struct sock *sk, struct iphdr *iph, struct tcphdr *th, u32 *cookie) { u16 mss = 0; #ifdef CONFIG_SYN_COOKIES mss = tcp_get_syncookie_mss(&tcp_request_sock_ops, &tcp_request_sock_ipv4_ops, sk, th); if (mss) { *cookie = __cookie_v4_init_sequence(iph, th, &mss); tcp_synq_overflow(sk); } #endif return mss; } INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *, u32)); /* The socket must have it's spinlock held when we get * here, unless it is a TCP_LISTEN socket. * * We have a potential double-lock case here, so even when * doing backlog processing we use the BH locking scheme. * This is because we cannot sleep with the original spinlock * held. */ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) { enum skb_drop_reason reason; struct sock *rsk; if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ struct dst_entry *dst; dst = rcu_dereference_protected(sk->sk_rx_dst, lockdep_sock_is_held(sk)); sock_rps_save_rxhash(sk, skb); sk_mark_napi_id(sk, skb); if (dst) { if (sk->sk_rx_dst_ifindex != skb->skb_iif || !INDIRECT_CALL_1(dst->ops->check, ipv4_dst_check, dst, 0)) { RCU_INIT_POINTER(sk->sk_rx_dst, NULL); dst_release(dst); } } tcp_rcv_established(sk, skb); return 0; } reason = SKB_DROP_REASON_NOT_SPECIFIED; if (tcp_checksum_complete(skb)) goto csum_err; if (sk->sk_state == TCP_LISTEN) { struct sock *nsk = tcp_v4_cookie_check(sk, skb); if (!nsk) goto discard; if (nsk != sk) { if (tcp_child_process(sk, nsk, skb)) { rsk = nsk; goto reset; } return 0; } } else sock_rps_save_rxhash(sk, skb); if (tcp_rcv_state_process(sk, skb)) { rsk = sk; goto reset; } return 0; reset: tcp_v4_send_reset(rsk, skb); discard: kfree_skb_reason(skb, reason); /* Be careful here. If this function gets more complicated and * gcc suffers from register pressure on the x86, sk (in %ebx) * might be destroyed here. This current version compiles correctly, * but you have been warned. */ return 0; csum_err: reason = SKB_DROP_REASON_TCP_CSUM; trace_tcp_bad_csum(skb); TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); goto discard; } EXPORT_SYMBOL(tcp_v4_do_rcv); int tcp_v4_early_demux(struct sk_buff *skb) { struct net *net = dev_net(skb->dev); const struct iphdr *iph; const struct tcphdr *th; struct sock *sk; if (skb->pkt_type != PACKET_HOST) return 0; if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) return 0; iph = ip_hdr(skb); th = tcp_hdr(skb); if (th->doff < sizeof(struct tcphdr) / 4) return 0; sk = __inet_lookup_established(net, net->ipv4.tcp_death_row.hashinfo, iph->saddr, th->source, iph->daddr, ntohs(th->dest), skb->skb_iif, inet_sdif(skb)); if (sk) { skb->sk = sk; skb->destructor = sock_edemux; if (sk_fullsock(sk)) { struct dst_entry *dst = rcu_dereference(sk->sk_rx_dst); if (dst) dst = dst_check(dst, 0); if (dst && sk->sk_rx_dst_ifindex == skb->skb_iif) skb_dst_set_noref(skb, dst); } } return 0; } bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb, enum skb_drop_reason *reason) { u32 limit, tail_gso_size, tail_gso_segs; struct skb_shared_info *shinfo; const struct tcphdr *th; struct tcphdr *thtail; struct sk_buff *tail; unsigned int hdrlen; bool fragstolen; u32 gso_segs; u32 gso_size; int delta; /* In case all data was pulled from skb frags (in __pskb_pull_tail()), * we can fix skb->truesize to its real value to avoid future drops. * This is valid because skb is not yet charged to the socket. * It has been noticed pure SACK packets were sometimes dropped * (if cooked by drivers without copybreak feature). */ skb_condense(skb); skb_dst_drop(skb); if (unlikely(tcp_checksum_complete(skb))) { bh_unlock_sock(sk); trace_tcp_bad_csum(skb); *reason = SKB_DROP_REASON_TCP_CSUM; __TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); __TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); return true; } /* Attempt coalescing to last skb in backlog, even if we are * above the limits. * This is okay because skb capacity is limited to MAX_SKB_FRAGS. */ th = (const struct tcphdr *)skb->data; hdrlen = th->doff * 4; tail = sk->sk_backlog.tail; if (!tail) goto no_coalesce; thtail = (struct tcphdr *)tail->data; if (TCP_SKB_CB(tail)->end_seq != TCP_SKB_CB(skb)->seq || TCP_SKB_CB(tail)->ip_dsfield != TCP_SKB_CB(skb)->ip_dsfield || ((TCP_SKB_CB(tail)->tcp_flags | TCP_SKB_CB(skb)->tcp_flags) & (TCPHDR_SYN | TCPHDR_RST | TCPHDR_URG)) || !((TCP_SKB_CB(tail)->tcp_flags & TCP_SKB_CB(skb)->tcp_flags) & TCPHDR_ACK) || ((TCP_SKB_CB(tail)->tcp_flags ^ TCP_SKB_CB(skb)->tcp_flags) & (TCPHDR_ECE | TCPHDR_CWR)) || #ifdef CONFIG_TLS_DEVICE tail->decrypted != skb->decrypted || #endif thtail->doff != th->doff || memcmp(thtail + 1, th + 1, hdrlen - sizeof(*th))) goto no_coalesce; __skb_pull(skb, hdrlen); shinfo = skb_shinfo(skb); gso_size = shinfo->gso_size ?: skb->len; gso_segs = shinfo->gso_segs ?: 1; shinfo = skb_shinfo(tail); tail_gso_size = shinfo->gso_size ?: (tail->len - hdrlen); tail_gso_segs = shinfo->gso_segs ?: 1; if (skb_try_coalesce(tail, skb, &fragstolen, &delta)) { TCP_SKB_CB(tail)->end_seq = TCP_SKB_CB(skb)->end_seq; if (likely(!before(TCP_SKB_CB(skb)->ack_seq, TCP_SKB_CB(tail)->ack_seq))) { TCP_SKB_CB(tail)->ack_seq = TCP_SKB_CB(skb)->ack_seq; thtail->window = th->window; } /* We have to update both TCP_SKB_CB(tail)->tcp_flags and * thtail->fin, so that the fast path in tcp_rcv_established() * is not entered if we append a packet with a FIN. * SYN, RST, URG are not present. * ACK is set on both packets. * PSH : we do not really care in TCP stack, * at least for 'GRO' packets. */ thtail->fin |= th->fin; TCP_SKB_CB(tail)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags; if (TCP_SKB_CB(skb)->has_rxtstamp) { TCP_SKB_CB(tail)->has_rxtstamp = true; tail->tstamp = skb->tstamp; skb_hwtstamps(tail)->hwtstamp = skb_hwtstamps(skb)->hwtstamp; } /* Not as strict as GRO. We only need to carry mss max value */ shinfo->gso_size = max(gso_size, tail_gso_size); shinfo->gso_segs = min_t(u32, gso_segs + tail_gso_segs, 0xFFFF); sk->sk_backlog.len += delta; __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGCOALESCE); kfree_skb_partial(skb, fragstolen); return false; } __skb_push(skb, hdrlen); no_coalesce: limit = (u32)READ_ONCE(sk->sk_rcvbuf) + (u32)(READ_ONCE(sk->sk_sndbuf) >> 1); /* Only socket owner can try to collapse/prune rx queues * to reduce memory overhead, so add a little headroom here. * Few sockets backlog are possibly concurrently non empty. */ limit += 64 * 1024; if (unlikely(sk_add_backlog(sk, skb, limit))) { bh_unlock_sock(sk); *reason = SKB_DROP_REASON_SOCKET_BACKLOG; __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGDROP); return true; } return false; } EXPORT_SYMBOL(tcp_add_backlog); int tcp_filter(struct sock *sk, struct sk_buff *skb) { struct tcphdr *th = (struct tcphdr *)skb->data; return sk_filter_trim_cap(sk, skb, th->doff * 4); } EXPORT_SYMBOL(tcp_filter); static void tcp_v4_restore_cb(struct sk_buff *skb) { memmove(IPCB(skb), &TCP_SKB_CB(skb)->header.h4, sizeof(struct inet_skb_parm)); } static void tcp_v4_fill_cb(struct sk_buff *skb, const struct iphdr *iph, const struct tcphdr *th) { /* This is tricky : We move IPCB at its correct location into TCP_SKB_CB() * barrier() makes sure compiler wont play fool^Waliasing games. */ memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb), sizeof(struct inet_skb_parm)); barrier(); TCP_SKB_CB(skb)->seq = ntohl(th->seq); TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + skb->len - th->doff * 4); TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); TCP_SKB_CB(skb)->tcp_tw_isn = 0; TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph); TCP_SKB_CB(skb)->sacked = 0; TCP_SKB_CB(skb)->has_rxtstamp = skb->tstamp || skb_hwtstamps(skb)->hwtstamp; } /* * From tcp_input.c */ int tcp_v4_rcv(struct sk_buff *skb) { struct net *net = dev_net(skb->dev); enum skb_drop_reason drop_reason; int sdif = inet_sdif(skb); int dif = inet_iif(skb); const struct iphdr *iph; const struct tcphdr *th; bool refcounted; struct sock *sk; int ret; drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; if (skb->pkt_type != PACKET_HOST) goto discard_it; /* Count it even if it's bad */ __TCP_INC_STATS(net, TCP_MIB_INSEGS); if (!pskb_may_pull(skb, sizeof(struct tcphdr))) goto discard_it; th = (const struct tcphdr *)skb->data; if (unlikely(th->doff < sizeof(struct tcphdr) / 4)) { drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL; goto bad_packet; } if (!pskb_may_pull(skb, th->doff * 4)) goto discard_it; /* An explanation is required here, I think. * Packet length and doff are validated by header prediction, * provided case of th->doff==0 is eliminated. * So, we defer the checks. */ if (skb_checksum_init(skb, IPPROTO_TCP, inet_compute_pseudo)) goto csum_error; th = (const struct tcphdr *)skb->data; iph = ip_hdr(skb); lookup: sk = __inet_lookup_skb(net->ipv4.tcp_death_row.hashinfo, skb, __tcp_hdrlen(th), th->source, th->dest, sdif, &refcounted); if (!sk) goto no_tcp_socket; process: if (sk->sk_state == TCP_TIME_WAIT) goto do_time_wait; if (sk->sk_state == TCP_NEW_SYN_RECV) { struct request_sock *req = inet_reqsk(sk); bool req_stolen = false; struct sock *nsk; sk = req->rsk_listener; if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) drop_reason = SKB_DROP_REASON_XFRM_POLICY; else drop_reason = tcp_inbound_md5_hash(sk, skb, &iph->saddr, &iph->daddr, AF_INET, dif, sdif); if (unlikely(drop_reason)) { sk_drops_add(sk, skb); reqsk_put(req); goto discard_it; } if (tcp_checksum_complete(skb)) { reqsk_put(req); goto csum_error; } if (unlikely(sk->sk_state != TCP_LISTEN)) { nsk = reuseport_migrate_sock(sk, req_to_sk(req), skb); if (!nsk) { inet_csk_reqsk_queue_drop_and_put(sk, req); goto lookup; } sk = nsk; /* reuseport_migrate_sock() has already held one sk_refcnt * before returning. */ } else { /* We own a reference on the listener, increase it again * as we might lose it too soon. */ sock_hold(sk); } refcounted = true; nsk = NULL; if (!tcp_filter(sk, skb)) { th = (const struct tcphdr *)skb->data; iph = ip_hdr(skb); tcp_v4_fill_cb(skb, iph, th); nsk = tcp_check_req(sk, skb, req, false, &req_stolen); } else { drop_reason = SKB_DROP_REASON_SOCKET_FILTER; } if (!nsk) { reqsk_put(req); if (req_stolen) { /* Another cpu got exclusive access to req * and created a full blown socket. * Try to feed this packet to this socket * instead of discarding it. */ tcp_v4_restore_cb(skb); sock_put(sk); goto lookup; } goto discard_and_relse; } nf_reset_ct(skb); if (nsk == sk) { reqsk_put(req); tcp_v4_restore_cb(skb); } else if (tcp_child_process(sk, nsk, skb)) { tcp_v4_send_reset(nsk, skb); goto discard_and_relse; } else { sock_put(sk); return 0; } } if (static_branch_unlikely(&ip4_min_ttl)) { /* min_ttl can be changed concurrently from do_ip_setsockopt() */ if (unlikely(iph->ttl < READ_ONCE(inet_sk(sk)->min_ttl))) { __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); drop_reason = SKB_DROP_REASON_TCP_MINTTL; goto discard_and_relse; } } if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) { drop_reason = SKB_DROP_REASON_XFRM_POLICY; goto discard_and_relse; } drop_reason = tcp_inbound_md5_hash(sk, skb, &iph->saddr, &iph->daddr, AF_INET, dif, sdif); if (drop_reason) goto discard_and_relse; nf_reset_ct(skb); if (tcp_filter(sk, skb)) { drop_reason = SKB_DROP_REASON_SOCKET_FILTER; goto discard_and_relse; } th = (const struct tcphdr *)skb->data; iph = ip_hdr(skb); tcp_v4_fill_cb(skb, iph, th); skb->dev = NULL; if (sk->sk_state == TCP_LISTEN) { ret = tcp_v4_do_rcv(sk, skb); goto put_and_return; } sk_incoming_cpu_update(sk); bh_lock_sock_nested(sk); tcp_segs_in(tcp_sk(sk), skb); ret = 0; if (!sock_owned_by_user(sk)) { ret = tcp_v4_do_rcv(sk, skb); } else { if (tcp_add_backlog(sk, skb, &drop_reason)) goto discard_and_relse; } bh_unlock_sock(sk); put_and_return: if (refcounted) sock_put(sk); return ret; no_tcp_socket: drop_reason = SKB_DROP_REASON_NO_SOCKET; if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) goto discard_it; tcp_v4_fill_cb(skb, iph, th); if (tcp_checksum_complete(skb)) { csum_error: drop_reason = SKB_DROP_REASON_TCP_CSUM; trace_tcp_bad_csum(skb); __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS); bad_packet: __TCP_INC_STATS(net, TCP_MIB_INERRS); } else { tcp_v4_send_reset(NULL, skb); } discard_it: SKB_DR_OR(drop_reason, NOT_SPECIFIED); /* Discard frame. */ kfree_skb_reason(skb, drop_reason); return 0; discard_and_relse: sk_drops_add(sk, skb); if (refcounted) sock_put(sk); goto discard_it; do_time_wait: if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { drop_reason = SKB_DROP_REASON_XFRM_POLICY; inet_twsk_put(inet_twsk(sk)); goto discard_it; } tcp_v4_fill_cb(skb, iph, th); if (tcp_checksum_complete(skb)) { inet_twsk_put(inet_twsk(sk)); goto csum_error; } switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { case TCP_TW_SYN: { struct sock *sk2 = inet_lookup_listener(net, net->ipv4.tcp_death_row.hashinfo, skb, __tcp_hdrlen(th), iph->saddr, th->source, iph->daddr, th->dest, inet_iif(skb), sdif); if (sk2) { inet_twsk_deschedule_put(inet_twsk(sk)); sk = sk2; tcp_v4_restore_cb(skb); refcounted = false; goto process; } } /* to ACK */ fallthrough; case TCP_TW_ACK: tcp_v4_timewait_ack(sk, skb); break; case TCP_TW_RST: tcp_v4_send_reset(sk, skb); inet_twsk_deschedule_put(inet_twsk(sk)); goto discard_it; case TCP_TW_SUCCESS:; } goto discard_it; } static struct timewait_sock_ops tcp_timewait_sock_ops = { .twsk_obj_size = sizeof(struct tcp_timewait_sock), .twsk_unique = tcp_twsk_unique, .twsk_destructor= tcp_twsk_destructor, }; void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); if (dst && dst_hold_safe(dst)) { rcu_assign_pointer(sk->sk_rx_dst, dst); sk->sk_rx_dst_ifindex = skb->skb_iif; } } EXPORT_SYMBOL(inet_sk_rx_dst_set); const struct inet_connection_sock_af_ops ipv4_specific = { .queue_xmit = ip_queue_xmit, .send_check = tcp_v4_send_check, .rebuild_header = inet_sk_rebuild_header, .sk_rx_dst_set = inet_sk_rx_dst_set, .conn_request = tcp_v4_conn_request, .syn_recv_sock = tcp_v4_syn_recv_sock, .net_header_len = sizeof(struct iphdr), .setsockopt = ip_setsockopt, .getsockopt = ip_getsockopt, .addr2sockaddr = inet_csk_addr2sockaddr, .sockaddr_len = sizeof(struct sockaddr_in), .mtu_reduced = tcp_v4_mtu_reduced, }; EXPORT_SYMBOL(ipv4_specific); #ifdef CONFIG_TCP_MD5SIG static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = { .md5_lookup = tcp_v4_md5_lookup, .calc_md5_hash = tcp_v4_md5_hash_skb, .md5_parse = tcp_v4_parse_md5_keys, }; #endif /* NOTE: A lot of things set to zero explicitly by call to * sk_alloc() so need not be done here. */ static int tcp_v4_init_sock(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); tcp_init_sock(sk); icsk->icsk_af_ops = &ipv4_specific; #ifdef CONFIG_TCP_MD5SIG tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific; #endif return 0; } void tcp_v4_destroy_sock(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); trace_tcp_destroy_sock(sk); tcp_clear_xmit_timers(sk); tcp_cleanup_congestion_control(sk); tcp_cleanup_ulp(sk); /* Cleanup up the write buffer. */ tcp_write_queue_purge(sk); /* Check if we want to disable active TFO */ tcp_fastopen_active_disable_ofo_check(sk); /* Cleans up our, hopefully empty, out_of_order_queue. */ skb_rbtree_purge(&tp->out_of_order_queue); #ifdef CONFIG_TCP_MD5SIG /* Clean up the MD5 key list, if any */ if (tp->md5sig_info) { tcp_clear_md5_list(sk); kfree_rcu(rcu_dereference_protected(tp->md5sig_info, 1), rcu); tp->md5sig_info = NULL; static_branch_slow_dec_deferred(&tcp_md5_needed); } #endif /* Clean up a referenced TCP bind bucket. */ if (inet_csk(sk)->icsk_bind_hash) inet_put_port(sk); BUG_ON(rcu_access_pointer(tp->fastopen_rsk)); /* If socket is aborted during connect operation */ tcp_free_fastopen_req(tp); tcp_fastopen_destroy_cipher(sk); tcp_saved_syn_free(tp); sk_sockets_allocated_dec(sk); } EXPORT_SYMBOL(tcp_v4_destroy_sock); #ifdef CONFIG_PROC_FS /* Proc filesystem TCP sock list dumping. */ static unsigned short seq_file_family(const struct seq_file *seq); static bool seq_sk_match(struct seq_file *seq, const struct sock *sk) { unsigned short family = seq_file_family(seq); /* AF_UNSPEC is used as a match all */ return ((family == AF_UNSPEC || family == sk->sk_family) && net_eq(sock_net(sk), seq_file_net(seq))); } /* Find a non empty bucket (starting from st->bucket) * and return the first sk from it. */ static void *listening_get_first(struct seq_file *seq) { struct inet_hashinfo *hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; struct tcp_iter_state *st = seq->private; st->offset = 0; for (; st->bucket <= hinfo->lhash2_mask; st->bucket++) { struct inet_listen_hashbucket *ilb2; struct hlist_nulls_node *node; struct sock *sk; ilb2 = &hinfo->lhash2[st->bucket]; if (hlist_nulls_empty(&ilb2->nulls_head)) continue; spin_lock(&ilb2->lock); sk_nulls_for_each(sk, node, &ilb2->nulls_head) { if (seq_sk_match(seq, sk)) return sk; } spin_unlock(&ilb2->lock); } return NULL; } /* Find the next sk of "cur" within the same bucket (i.e. st->bucket). * If "cur" is the last one in the st->bucket, * call listening_get_first() to return the first sk of the next * non empty bucket. */ static void *listening_get_next(struct seq_file *seq, void *cur) { struct tcp_iter_state *st = seq->private; struct inet_listen_hashbucket *ilb2; struct hlist_nulls_node *node; struct inet_hashinfo *hinfo; struct sock *sk = cur; ++st->num; ++st->offset; sk = sk_nulls_next(sk); sk_nulls_for_each_from(sk, node) { if (seq_sk_match(seq, sk)) return sk; } hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; ilb2 = &hinfo->lhash2[st->bucket]; spin_unlock(&ilb2->lock); ++st->bucket; return listening_get_first(seq); } static void *listening_get_idx(struct seq_file *seq, loff_t *pos) { struct tcp_iter_state *st = seq->private; void *rc; st->bucket = 0; st->offset = 0; rc = listening_get_first(seq); while (rc && *pos) { rc = listening_get_next(seq, rc); --*pos; } return rc; } static inline bool empty_bucket(struct inet_hashinfo *hinfo, const struct tcp_iter_state *st) { return hlist_nulls_empty(&hinfo->ehash[st->bucket].chain); } /* * Get first established socket starting from bucket given in st->bucket. * If st->bucket is zero, the very first socket in the hash is returned. */ static void *established_get_first(struct seq_file *seq) { struct inet_hashinfo *hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; struct tcp_iter_state *st = seq->private; st->offset = 0; for (; st->bucket <= hinfo->ehash_mask; ++st->bucket) { struct sock *sk; struct hlist_nulls_node *node; spinlock_t *lock = inet_ehash_lockp(hinfo, st->bucket); cond_resched(); /* Lockless fast path for the common case of empty buckets */ if (empty_bucket(hinfo, st)) continue; spin_lock_bh(lock); sk_nulls_for_each(sk, node, &hinfo->ehash[st->bucket].chain) { if (seq_sk_match(seq, sk)) return sk; } spin_unlock_bh(lock); } return NULL; } static void *established_get_next(struct seq_file *seq, void *cur) { struct inet_hashinfo *hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; struct tcp_iter_state *st = seq->private; struct hlist_nulls_node *node; struct sock *sk = cur; ++st->num; ++st->offset; sk = sk_nulls_next(sk); sk_nulls_for_each_from(sk, node) { if (seq_sk_match(seq, sk)) return sk; } spin_unlock_bh(inet_ehash_lockp(hinfo, st->bucket)); ++st->bucket; return established_get_first(seq); } static void *established_get_idx(struct seq_file *seq, loff_t pos) { struct tcp_iter_state *st = seq->private; void *rc; st->bucket = 0; rc = established_get_first(seq); while (rc && pos) { rc = established_get_next(seq, rc); --pos; } return rc; } static void *tcp_get_idx(struct seq_file *seq, loff_t pos) { void *rc; struct tcp_iter_state *st = seq->private; st->state = TCP_SEQ_STATE_LISTENING; rc = listening_get_idx(seq, &pos); if (!rc) { st->state = TCP_SEQ_STATE_ESTABLISHED; rc = established_get_idx(seq, pos); } return rc; } static void *tcp_seek_last_pos(struct seq_file *seq) { struct inet_hashinfo *hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; struct tcp_iter_state *st = seq->private; int bucket = st->bucket; int offset = st->offset; int orig_num = st->num; void *rc = NULL; switch (st->state) { case TCP_SEQ_STATE_LISTENING: if (st->bucket > hinfo->lhash2_mask) break; rc = listening_get_first(seq); while (offset-- && rc && bucket == st->bucket) rc = listening_get_next(seq, rc); if (rc) break; st->bucket = 0; st->state = TCP_SEQ_STATE_ESTABLISHED; fallthrough; case TCP_SEQ_STATE_ESTABLISHED: if (st->bucket > hinfo->ehash_mask) break; rc = established_get_first(seq); while (offset-- && rc && bucket == st->bucket) rc = established_get_next(seq, rc); } st->num = orig_num; return rc; } void *tcp_seq_start(struct seq_file *seq, loff_t *pos) { struct tcp_iter_state *st = seq->private; void *rc; if (*pos && *pos == st->last_pos) { rc = tcp_seek_last_pos(seq); if (rc) goto out; } st->state = TCP_SEQ_STATE_LISTENING; st->num = 0; st->bucket = 0; st->offset = 0; rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; out: st->last_pos = *pos; return rc; } EXPORT_SYMBOL(tcp_seq_start); void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct tcp_iter_state *st = seq->private; void *rc = NULL; if (v == SEQ_START_TOKEN) { rc = tcp_get_idx(seq, 0); goto out; } switch (st->state) { case TCP_SEQ_STATE_LISTENING: rc = listening_get_next(seq, v); if (!rc) { st->state = TCP_SEQ_STATE_ESTABLISHED; st->bucket = 0; st->offset = 0; rc = established_get_first(seq); } break; case TCP_SEQ_STATE_ESTABLISHED: rc = established_get_next(seq, v); break; } out: ++*pos; st->last_pos = *pos; return rc; } EXPORT_SYMBOL(tcp_seq_next); void tcp_seq_stop(struct seq_file *seq, void *v) { struct inet_hashinfo *hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; struct tcp_iter_state *st = seq->private; switch (st->state) { case TCP_SEQ_STATE_LISTENING: if (v != SEQ_START_TOKEN) spin_unlock(&hinfo->lhash2[st->bucket].lock); break; case TCP_SEQ_STATE_ESTABLISHED: if (v) spin_unlock_bh(inet_ehash_lockp(hinfo, st->bucket)); break; } } EXPORT_SYMBOL(tcp_seq_stop); static void get_openreq4(const struct request_sock *req, struct seq_file *f, int i) { const struct inet_request_sock *ireq = inet_rsk(req); long delta = req->rsk_timer.expires - jiffies; seq_printf(f, "%4d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5u %8d %u %d %pK", i, ireq->ir_loc_addr, ireq->ir_num, ireq->ir_rmt_addr, ntohs(ireq->ir_rmt_port), TCP_SYN_RECV, 0, 0, /* could print option size, but that is af dependent. */ 1, /* timers active (only the expire timer) */ jiffies_delta_to_clock_t(delta), req->num_timeout, from_kuid_munged(seq_user_ns(f), sock_i_uid(req->rsk_listener)), 0, /* non standard timer */ 0, /* open_requests have no inode */ 0, req); } static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i) { int timer_active; unsigned long timer_expires; const struct tcp_sock *tp = tcp_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); const struct inet_sock *inet = inet_sk(sk); const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; __be32 dest = inet->inet_daddr; __be32 src = inet->inet_rcv_saddr; __u16 destp = ntohs(inet->inet_dport); __u16 srcp = ntohs(inet->inet_sport); int rx_queue; int state; if (icsk->icsk_pending == ICSK_TIME_RETRANS || icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { timer_active = 1; timer_expires = icsk->icsk_timeout; } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { timer_active = 4; timer_expires = icsk->icsk_timeout; } else if (timer_pending(&sk->sk_timer)) { timer_active = 2; timer_expires = sk->sk_timer.expires; } else { timer_active = 0; timer_expires = jiffies; } state = inet_sk_state_load(sk); if (state == TCP_LISTEN) rx_queue = READ_ONCE(sk->sk_ack_backlog); else /* Because we don't lock the socket, * we might find a transient negative value. */ rx_queue = max_t(int, READ_ONCE(tp->rcv_nxt) - READ_ONCE(tp->copied_seq), 0); seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " "%08X %5u %8d %lu %d %pK %lu %lu %u %u %d", i, src, srcp, dest, destp, state, READ_ONCE(tp->write_seq) - tp->snd_una, rx_queue, timer_active, jiffies_delta_to_clock_t(timer_expires - jiffies), icsk->icsk_retransmits, from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)), icsk->icsk_probes_out, sock_i_ino(sk), refcount_read(&sk->sk_refcnt), sk, jiffies_to_clock_t(icsk->icsk_rto), jiffies_to_clock_t(icsk->icsk_ack.ato), (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(sk), tcp_snd_cwnd(tp), state == TCP_LISTEN ? fastopenq->max_qlen : (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh)); } static void get_timewait4_sock(const struct inet_timewait_sock *tw, struct seq_file *f, int i) { long delta = tw->tw_timer.expires - jiffies; __be32 dest, src; __u16 destp, srcp; dest = tw->tw_daddr; src = tw->tw_rcv_saddr; destp = ntohs(tw->tw_dport); srcp = ntohs(tw->tw_sport); seq_printf(f, "%4d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK", i, src, srcp, dest, destp, tw->tw_substate, 0, 0, 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, refcount_read(&tw->tw_refcnt), tw); } #define TMPSZ 150 static int tcp4_seq_show(struct seq_file *seq, void *v) { struct tcp_iter_state *st; struct sock *sk = v; seq_setwidth(seq, TMPSZ - 1); if (v == SEQ_START_TOKEN) { seq_puts(seq, " sl local_address rem_address st tx_queue " "rx_queue tr tm->when retrnsmt uid timeout " "inode"); goto out; } st = seq->private; if (sk->sk_state == TCP_TIME_WAIT) get_timewait4_sock(v, seq, st->num); else if (sk->sk_state == TCP_NEW_SYN_RECV) get_openreq4(v, seq, st->num); else get_tcp4_sock(v, seq, st->num); out: seq_pad(seq, '\n'); return 0; } #ifdef CONFIG_BPF_SYSCALL struct bpf_tcp_iter_state { struct tcp_iter_state state; unsigned int cur_sk; unsigned int end_sk; unsigned int max_sk; struct sock **batch; bool st_bucket_done; }; struct bpf_iter__tcp { __bpf_md_ptr(struct bpf_iter_meta *, meta); __bpf_md_ptr(struct sock_common *, sk_common); uid_t uid __aligned(8); }; static int tcp_prog_seq_show(struct bpf_prog *prog, struct bpf_iter_meta *meta, struct sock_common *sk_common, uid_t uid) { struct bpf_iter__tcp ctx; meta->seq_num--; /* skip SEQ_START_TOKEN */ ctx.meta = meta; ctx.sk_common = sk_common; ctx.uid = uid; return bpf_iter_run_prog(prog, &ctx); } static void bpf_iter_tcp_put_batch(struct bpf_tcp_iter_state *iter) { while (iter->cur_sk < iter->end_sk) sock_gen_put(iter->batch[iter->cur_sk++]); } static int bpf_iter_tcp_realloc_batch(struct bpf_tcp_iter_state *iter, unsigned int new_batch_sz) { struct sock **new_batch; new_batch = kvmalloc(sizeof(*new_batch) * new_batch_sz, GFP_USER | __GFP_NOWARN); if (!new_batch) return -ENOMEM; bpf_iter_tcp_put_batch(iter); kvfree(iter->batch); iter->batch = new_batch; iter->max_sk = new_batch_sz; return 0; } static unsigned int bpf_iter_tcp_listening_batch(struct seq_file *seq, struct sock *start_sk) { struct inet_hashinfo *hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; struct bpf_tcp_iter_state *iter = seq->private; struct tcp_iter_state *st = &iter->state; struct hlist_nulls_node *node; unsigned int expected = 1; struct sock *sk; sock_hold(start_sk); iter->batch[iter->end_sk++] = start_sk; sk = sk_nulls_next(start_sk); sk_nulls_for_each_from(sk, node) { if (seq_sk_match(seq, sk)) { if (iter->end_sk < iter->max_sk) { sock_hold(sk); iter->batch[iter->end_sk++] = sk; } expected++; } } spin_unlock(&hinfo->lhash2[st->bucket].lock); return expected; } static unsigned int bpf_iter_tcp_established_batch(struct seq_file *seq, struct sock *start_sk) { struct inet_hashinfo *hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; struct bpf_tcp_iter_state *iter = seq->private; struct tcp_iter_state *st = &iter->state; struct hlist_nulls_node *node; unsigned int expected = 1; struct sock *sk; sock_hold(start_sk); iter->batch[iter->end_sk++] = start_sk; sk = sk_nulls_next(start_sk); sk_nulls_for_each_from(sk, node) { if (seq_sk_match(seq, sk)) { if (iter->end_sk < iter->max_sk) { sock_hold(sk); iter->batch[iter->end_sk++] = sk; } expected++; } } spin_unlock_bh(inet_ehash_lockp(hinfo, st->bucket)); return expected; } static struct sock *bpf_iter_tcp_batch(struct seq_file *seq) { struct inet_hashinfo *hinfo = seq_file_net(seq)->ipv4.tcp_death_row.hashinfo; struct bpf_tcp_iter_state *iter = seq->private; struct tcp_iter_state *st = &iter->state; unsigned int expected; bool resized = false; struct sock *sk; /* The st->bucket is done. Directly advance to the next * bucket instead of having the tcp_seek_last_pos() to skip * one by one in the current bucket and eventually find out * it has to advance to the next bucket. */ if (iter->st_bucket_done) { st->offset = 0; st->bucket++; if (st->state == TCP_SEQ_STATE_LISTENING && st->bucket > hinfo->lhash2_mask) { st->state = TCP_SEQ_STATE_ESTABLISHED; st->bucket = 0; } } again: /* Get a new batch */ iter->cur_sk = 0; iter->end_sk = 0; iter->st_bucket_done = false; sk = tcp_seek_last_pos(seq); if (!sk) return NULL; /* Done */ if (st->state == TCP_SEQ_STATE_LISTENING) expected = bpf_iter_tcp_listening_batch(seq, sk); else expected = bpf_iter_tcp_established_batch(seq, sk); if (iter->end_sk == expected) { iter->st_bucket_done = true; return sk; } if (!resized && !bpf_iter_tcp_realloc_batch(iter, expected * 3 / 2)) { resized = true; goto again; } return sk; } static void *bpf_iter_tcp_seq_start(struct seq_file *seq, loff_t *pos) { /* bpf iter does not support lseek, so it always * continue from where it was stop()-ped. */ if (*pos) return bpf_iter_tcp_batch(seq); return SEQ_START_TOKEN; } static void *bpf_iter_tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct bpf_tcp_iter_state *iter = seq->private; struct tcp_iter_state *st = &iter->state; struct sock *sk; /* Whenever seq_next() is called, the iter->cur_sk is * done with seq_show(), so advance to the next sk in * the batch. */ if (iter->cur_sk < iter->end_sk) { /* Keeping st->num consistent in tcp_iter_state. * bpf_iter_tcp does not use st->num. * meta.seq_num is used instead. */ st->num++; /* Move st->offset to the next sk in the bucket such that * the future start() will resume at st->offset in * st->bucket. See tcp_seek_last_pos(). */ st->offset++; sock_gen_put(iter->batch[iter->cur_sk++]); } if (iter->cur_sk < iter->end_sk) sk = iter->batch[iter->cur_sk]; else sk = bpf_iter_tcp_batch(seq); ++*pos; /* Keeping st->last_pos consistent in tcp_iter_state. * bpf iter does not do lseek, so st->last_pos always equals to *pos. */ st->last_pos = *pos; return sk; } static int bpf_iter_tcp_seq_show(struct seq_file *seq, void *v) { struct bpf_iter_meta meta; struct bpf_prog *prog; struct sock *sk = v; uid_t uid; int ret; if (v == SEQ_START_TOKEN) return 0; if (sk_fullsock(sk)) lock_sock(sk); if (unlikely(sk_unhashed(sk))) { ret = SEQ_SKIP; goto unlock; } if (sk->sk_state == TCP_TIME_WAIT) { uid = 0; } else if (sk->sk_state == TCP_NEW_SYN_RECV) { const struct request_sock *req = v; uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(req->rsk_listener)); } else { uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)); } meta.seq = seq; prog = bpf_iter_get_info(&meta, false); ret = tcp_prog_seq_show(prog, &meta, v, uid); unlock: if (sk_fullsock(sk)) release_sock(sk); return ret; } static void bpf_iter_tcp_seq_stop(struct seq_file *seq, void *v) { struct bpf_tcp_iter_state *iter = seq->private; struct bpf_iter_meta meta; struct bpf_prog *prog; if (!v) { meta.seq = seq; prog = bpf_iter_get_info(&meta, true); if (prog) (void)tcp_prog_seq_show(prog, &meta, v, 0); } if (iter->cur_sk < iter->end_sk) { bpf_iter_tcp_put_batch(iter); iter->st_bucket_done = false; } } static const struct seq_operations bpf_iter_tcp_seq_ops = { .show = bpf_iter_tcp_seq_show, .start = bpf_iter_tcp_seq_start, .next = bpf_iter_tcp_seq_next, .stop = bpf_iter_tcp_seq_stop, }; #endif static unsigned short seq_file_family(const struct seq_file *seq) { const struct tcp_seq_afinfo *afinfo; #ifdef CONFIG_BPF_SYSCALL /* Iterated from bpf_iter. Let the bpf prog to filter instead. */ if (seq->op == &bpf_iter_tcp_seq_ops) return AF_UNSPEC; #endif /* Iterated from proc fs */ afinfo = pde_data(file_inode(seq->file)); return afinfo->family; } static const struct seq_operations tcp4_seq_ops = { .show = tcp4_seq_show, .start = tcp_seq_start, .next = tcp_seq_next, .stop = tcp_seq_stop, }; static struct tcp_seq_afinfo tcp4_seq_afinfo = { .family = AF_INET, }; static int __net_init tcp4_proc_init_net(struct net *net) { if (!proc_create_net_data("tcp", 0444, net->proc_net, &tcp4_seq_ops, sizeof(struct tcp_iter_state), &tcp4_seq_afinfo)) return -ENOMEM; return 0; } static void __net_exit tcp4_proc_exit_net(struct net *net) { remove_proc_entry("tcp", net->proc_net); } static struct pernet_operations tcp4_net_ops = { .init = tcp4_proc_init_net, .exit = tcp4_proc_exit_net, }; int __init tcp4_proc_init(void) { return register_pernet_subsys(&tcp4_net_ops); } void tcp4_proc_exit(void) { unregister_pernet_subsys(&tcp4_net_ops); } #endif /* CONFIG_PROC_FS */ /* @wake is one when sk_stream_write_space() calls us. * This sends EPOLLOUT only if notsent_bytes is half the limit. * This mimics the strategy used in sock_def_write_space(). */ bool tcp_stream_memory_free(const struct sock *sk, int wake) { const struct tcp_sock *tp = tcp_sk(sk); u32 notsent_bytes = READ_ONCE(tp->write_seq) - READ_ONCE(tp->snd_nxt); return (notsent_bytes << wake) < tcp_notsent_lowat(tp); } EXPORT_SYMBOL(tcp_stream_memory_free); struct proto tcp_prot = { .name = "TCP", .owner = THIS_MODULE, .close = tcp_close, .pre_connect = tcp_v4_pre_connect, .connect = tcp_v4_connect, .disconnect = tcp_disconnect, .accept = inet_csk_accept, .ioctl = tcp_ioctl, .init = tcp_v4_init_sock, .destroy = tcp_v4_destroy_sock, .shutdown = tcp_shutdown, .setsockopt = tcp_setsockopt, .getsockopt = tcp_getsockopt, .bpf_bypass_getsockopt = tcp_bpf_bypass_getsockopt, .keepalive = tcp_set_keepalive, .recvmsg = tcp_recvmsg, .sendmsg = tcp_sendmsg, .splice_eof = tcp_splice_eof, .backlog_rcv = tcp_v4_do_rcv, .release_cb = tcp_release_cb, .hash = inet_hash, .unhash = inet_unhash, .get_port = inet_csk_get_port, .put_port = inet_put_port, #ifdef CONFIG_BPF_SYSCALL .psock_update_sk_prot = tcp_bpf_update_proto, #endif .enter_memory_pressure = tcp_enter_memory_pressure, .leave_memory_pressure = tcp_leave_memory_pressure, .stream_memory_free = tcp_stream_memory_free, .sockets_allocated = &tcp_sockets_allocated, .orphan_count = &tcp_orphan_count, .memory_allocated = &tcp_memory_allocated, .per_cpu_fw_alloc = &tcp_memory_per_cpu_fw_alloc, .memory_pressure = &tcp_memory_pressure, .sysctl_mem = sysctl_tcp_mem, .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_tcp_wmem), .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_tcp_rmem), .max_header = MAX_TCP_HEADER, .obj_size = sizeof(struct tcp_sock), .slab_flags = SLAB_TYPESAFE_BY_RCU, .twsk_prot = &tcp_timewait_sock_ops, .rsk_prot = &tcp_request_sock_ops, .h.hashinfo = NULL, .no_autobind = true, .diag_destroy = tcp_abort, }; EXPORT_SYMBOL(tcp_prot); static void __net_exit tcp_sk_exit(struct net *net) { if (net->ipv4.tcp_congestion_control) bpf_module_put(net->ipv4.tcp_congestion_control, net->ipv4.tcp_congestion_control->owner); } static void __net_init tcp_set_hashinfo(struct net *net) { struct inet_hashinfo *hinfo; unsigned int ehash_entries; struct net *old_net; if (net_eq(net, &init_net)) goto fallback; old_net = current->nsproxy->net_ns; ehash_entries = READ_ONCE(old_net->ipv4.sysctl_tcp_child_ehash_entries); if (!ehash_entries) goto fallback; ehash_entries = roundup_pow_of_two(ehash_entries); hinfo = inet_pernet_hashinfo_alloc(&tcp_hashinfo, ehash_entries); if (!hinfo) { pr_warn("Failed to allocate TCP ehash (entries: %u) " "for a netns, fallback to the global one\n", ehash_entries); fallback: hinfo = &tcp_hashinfo; ehash_entries = tcp_hashinfo.ehash_mask + 1; } net->ipv4.tcp_death_row.hashinfo = hinfo; net->ipv4.tcp_death_row.sysctl_max_tw_buckets = ehash_entries / 2; net->ipv4.sysctl_max_syn_backlog = max(128U, ehash_entries / 128); } static int __net_init tcp_sk_init(struct net *net) { net->ipv4.sysctl_tcp_ecn = 2; net->ipv4.sysctl_tcp_ecn_fallback = 1; net->ipv4.sysctl_tcp_base_mss = TCP_BASE_MSS; net->ipv4.sysctl_tcp_min_snd_mss = TCP_MIN_SND_MSS; net->ipv4.sysctl_tcp_probe_threshold = TCP_PROBE_THRESHOLD; net->ipv4.sysctl_tcp_probe_interval = TCP_PROBE_INTERVAL; net->ipv4.sysctl_tcp_mtu_probe_floor = TCP_MIN_SND_MSS; net->ipv4.sysctl_tcp_keepalive_time = TCP_KEEPALIVE_TIME; net->ipv4.sysctl_tcp_keepalive_probes = TCP_KEEPALIVE_PROBES; net->ipv4.sysctl_tcp_keepalive_intvl = TCP_KEEPALIVE_INTVL; net->ipv4.sysctl_tcp_syn_retries = TCP_SYN_RETRIES; net->ipv4.sysctl_tcp_synack_retries = TCP_SYNACK_RETRIES; net->ipv4.sysctl_tcp_syncookies = 1; net->ipv4.sysctl_tcp_reordering = TCP_FASTRETRANS_THRESH; net->ipv4.sysctl_tcp_retries1 = TCP_RETR1; net->ipv4.sysctl_tcp_retries2 = TCP_RETR2; net->ipv4.sysctl_tcp_orphan_retries = 0; net->ipv4.sysctl_tcp_fin_timeout = TCP_FIN_TIMEOUT; net->ipv4.sysctl_tcp_notsent_lowat = UINT_MAX; net->ipv4.sysctl_tcp_tw_reuse = 2; net->ipv4.sysctl_tcp_no_ssthresh_metrics_save = 1; refcount_set(&net->ipv4.tcp_death_row.tw_refcount, 1); tcp_set_hashinfo(net); net->ipv4.sysctl_tcp_sack = 1; net->ipv4.sysctl_tcp_window_scaling = 1; net->ipv4.sysctl_tcp_timestamps = 1; net->ipv4.sysctl_tcp_early_retrans = 3; net->ipv4.sysctl_tcp_recovery = TCP_RACK_LOSS_DETECTION; net->ipv4.sysctl_tcp_slow_start_after_idle = 1; /* By default, RFC2861 behavior. */ net->ipv4.sysctl_tcp_retrans_collapse = 1; net->ipv4.sysctl_tcp_max_reordering = 300; net->ipv4.sysctl_tcp_dsack = 1; net->ipv4.sysctl_tcp_app_win = 31; net->ipv4.sysctl_tcp_adv_win_scale = 1; net->ipv4.sysctl_tcp_frto = 2; net->ipv4.sysctl_tcp_moderate_rcvbuf = 1; /* This limits the percentage of the congestion window which we * will allow a single TSO frame to consume. Building TSO frames * which are too large can cause TCP streams to be bursty. */ net->ipv4.sysctl_tcp_tso_win_divisor = 3; /* Default TSQ limit of 16 TSO segments */ net->ipv4.sysctl_tcp_limit_output_bytes = 16 * 65536; /* rfc5961 challenge ack rate limiting, per net-ns, disabled by default. */ net->ipv4.sysctl_tcp_challenge_ack_limit = INT_MAX; net->ipv4.sysctl_tcp_min_tso_segs = 2; net->ipv4.sysctl_tcp_tso_rtt_log = 9; /* 2^9 = 512 usec */ net->ipv4.sysctl_tcp_min_rtt_wlen = 300; net->ipv4.sysctl_tcp_autocorking = 1; net->ipv4.sysctl_tcp_invalid_ratelimit = HZ/2; net->ipv4.sysctl_tcp_pacing_ss_ratio = 200; net->ipv4.sysctl_tcp_pacing_ca_ratio = 120; if (net != &init_net) { memcpy(net->ipv4.sysctl_tcp_rmem, init_net.ipv4.sysctl_tcp_rmem, sizeof(init_net.ipv4.sysctl_tcp_rmem)); memcpy(net->ipv4.sysctl_tcp_wmem, init_net.ipv4.sysctl_tcp_wmem, sizeof(init_net.ipv4.sysctl_tcp_wmem)); } net->ipv4.sysctl_tcp_comp_sack_delay_ns = NSEC_PER_MSEC; net->ipv4.sysctl_tcp_comp_sack_slack_ns = 100 * NSEC_PER_USEC; net->ipv4.sysctl_tcp_comp_sack_nr = 44; net->ipv4.sysctl_tcp_fastopen = TFO_CLIENT_ENABLE; net->ipv4.sysctl_tcp_fastopen_blackhole_timeout = 0; atomic_set(&net->ipv4.tfo_active_disable_times, 0); /* Set default values for PLB */ net->ipv4.sysctl_tcp_plb_enabled = 0; /* Disabled by default */ net->ipv4.sysctl_tcp_plb_idle_rehash_rounds = 3; net->ipv4.sysctl_tcp_plb_rehash_rounds = 12; net->ipv4.sysctl_tcp_plb_suspend_rto_sec = 60; /* Default congestion threshold for PLB to mark a round is 50% */ net->ipv4.sysctl_tcp_plb_cong_thresh = (1 << TCP_PLB_SCALE) / 2; /* Reno is always built in */ if (!net_eq(net, &init_net) && bpf_try_module_get(init_net.ipv4.tcp_congestion_control, init_net.ipv4.tcp_congestion_control->owner)) net->ipv4.tcp_congestion_control = init_net.ipv4.tcp_congestion_control; else net->ipv4.tcp_congestion_control = &tcp_reno; net->ipv4.sysctl_tcp_syn_linear_timeouts = 4; net->ipv4.sysctl_tcp_shrink_window = 0; return 0; } static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list) { struct net *net; tcp_twsk_purge(net_exit_list, AF_INET); list_for_each_entry(net, net_exit_list, exit_list) { inet_pernet_hashinfo_free(net->ipv4.tcp_death_row.hashinfo); WARN_ON_ONCE(!refcount_dec_and_test(&net->ipv4.tcp_death_row.tw_refcount)); tcp_fastopen_ctx_destroy(net); } } static struct pernet_operations __net_initdata tcp_sk_ops = { .init = tcp_sk_init, .exit = tcp_sk_exit, .exit_batch = tcp_sk_exit_batch, }; #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) DEFINE_BPF_ITER_FUNC(tcp, struct bpf_iter_meta *meta, struct sock_common *sk_common, uid_t uid) #define INIT_BATCH_SZ 16 static int bpf_iter_init_tcp(void *priv_data, struct bpf_iter_aux_info *aux) { struct bpf_tcp_iter_state *iter = priv_data; int err; err = bpf_iter_init_seq_net(priv_data, aux); if (err) return err; err = bpf_iter_tcp_realloc_batch(iter, INIT_BATCH_SZ); if (err) { bpf_iter_fini_seq_net(priv_data); return err; } return 0; } static void bpf_iter_fini_tcp(void *priv_data) { struct bpf_tcp_iter_state *iter = priv_data; bpf_iter_fini_seq_net(priv_data); kvfree(iter->batch); } static const struct bpf_iter_seq_info tcp_seq_info = { .seq_ops = &bpf_iter_tcp_seq_ops, .init_seq_private = bpf_iter_init_tcp, .fini_seq_private = bpf_iter_fini_tcp, .seq_priv_size = sizeof(struct bpf_tcp_iter_state), }; static const struct bpf_func_proto * bpf_iter_tcp_get_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_setsockopt: return &bpf_sk_setsockopt_proto; case BPF_FUNC_getsockopt: return &bpf_sk_getsockopt_proto; default: return NULL; } } static struct bpf_iter_reg tcp_reg_info = { .target = "tcp", .ctx_arg_info_size = 1, .ctx_arg_info = { { offsetof(struct bpf_iter__tcp, sk_common), PTR_TO_BTF_ID_OR_NULL | PTR_TRUSTED }, }, .get_func_proto = bpf_iter_tcp_get_func_proto, .seq_info = &tcp_seq_info, }; static void __init bpf_iter_register(void) { tcp_reg_info.ctx_arg_info[0].btf_id = btf_sock_ids[BTF_SOCK_TYPE_SOCK_COMMON]; if (bpf_iter_reg_target(&tcp_reg_info)) pr_warn("Warning: could not register bpf iterator tcp\n"); } #endif void __init tcp_v4_init(void) { int cpu, res; for_each_possible_cpu(cpu) { struct sock *sk; res = inet_ctl_sock_create(&sk, PF_INET, SOCK_RAW, IPPROTO_TCP, &init_net); if (res) panic("Failed to create the TCP control socket.\n"); sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); /* Please enforce IP_DF and IPID==0 for RST and * ACK sent in SYN-RECV and TIME-WAIT state. */ inet_sk(sk)->pmtudisc = IP_PMTUDISC_DO; per_cpu(ipv4_tcp_sk, cpu) = sk; } if (register_pernet_subsys(&tcp_sk_ops)) panic("Failed to create the TCP control socket.\n"); #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) bpf_iter_register(); #endif }
linux-master
net/ipv4/tcp_ipv4.c
// SPDX-License-Identifier: GPL-2.0-only /* * * YeAH TCP * * For further details look at: * https://web.archive.org/web/20080316215752/http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf * */ #include <linux/mm.h> #include <linux/module.h> #include <linux/skbuff.h> #include <linux/inet_diag.h> #include <net/tcp.h> #include "tcp_vegas.h" #define TCP_YEAH_ALPHA 80 /* number of packets queued at the bottleneck */ #define TCP_YEAH_GAMMA 1 /* fraction of queue to be removed per rtt */ #define TCP_YEAH_DELTA 3 /* log minimum fraction of cwnd to be removed on loss */ #define TCP_YEAH_EPSILON 1 /* log maximum fraction to be removed on early decongestion */ #define TCP_YEAH_PHY 8 /* maximum delta from base */ #define TCP_YEAH_RHO 16 /* minimum number of consecutive rtt to consider competition on loss */ #define TCP_YEAH_ZETA 50 /* minimum number of state switches to reset reno_count */ #define TCP_SCALABLE_AI_CNT 100U /* YeAH variables */ struct yeah { struct vegas vegas; /* must be first */ /* YeAH */ u32 lastQ; u32 doing_reno_now; u32 reno_count; u32 fast_count; }; static void tcp_yeah_init(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct yeah *yeah = inet_csk_ca(sk); tcp_vegas_init(sk); yeah->doing_reno_now = 0; yeah->lastQ = 0; yeah->reno_count = 2; /* Ensure the MD arithmetic works. This is somewhat pedantic, * since I don't think we will see a cwnd this large. :) */ tp->snd_cwnd_clamp = min_t(u32, tp->snd_cwnd_clamp, 0xffffffff/128); } static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct yeah *yeah = inet_csk_ca(sk); if (!tcp_is_cwnd_limited(sk)) return; if (tcp_in_slow_start(tp)) { acked = tcp_slow_start(tp, acked); if (!acked) goto do_vegas; } if (!yeah->doing_reno_now) { /* Scalable */ tcp_cong_avoid_ai(tp, min(tcp_snd_cwnd(tp), TCP_SCALABLE_AI_CNT), acked); } else { /* Reno */ tcp_cong_avoid_ai(tp, tcp_snd_cwnd(tp), acked); } /* The key players are v_vegas.beg_snd_una and v_beg_snd_nxt. * * These are so named because they represent the approximate values * of snd_una and snd_nxt at the beginning of the current RTT. More * precisely, they represent the amount of data sent during the RTT. * At the end of the RTT, when we receive an ACK for v_beg_snd_nxt, * we will calculate that (v_beg_snd_nxt - v_vegas.beg_snd_una) outstanding * bytes of data have been ACKed during the course of the RTT, giving * an "actual" rate of: * * (v_beg_snd_nxt - v_vegas.beg_snd_una) / (rtt duration) * * Unfortunately, v_vegas.beg_snd_una is not exactly equal to snd_una, * because delayed ACKs can cover more than one segment, so they * don't line up yeahly with the boundaries of RTTs. * * Another unfortunate fact of life is that delayed ACKs delay the * advance of the left edge of our send window, so that the number * of bytes we send in an RTT is often less than our cwnd will allow. * So we keep track of our cwnd separately, in v_beg_snd_cwnd. */ do_vegas: if (after(ack, yeah->vegas.beg_snd_nxt)) { /* We do the Vegas calculations only if we got enough RTT * samples that we can be reasonably sure that we got * at least one RTT sample that wasn't from a delayed ACK. * If we only had 2 samples total, * then that means we're getting only 1 ACK per RTT, which * means they're almost certainly delayed ACKs. * If we have 3 samples, we should be OK. */ if (yeah->vegas.cntRTT > 2) { u32 rtt, queue; u64 bw; /* We have enough RTT samples, so, using the Vegas * algorithm, we determine if we should increase or * decrease cwnd, and by how much. */ /* Pluck out the RTT we are using for the Vegas * calculations. This is the min RTT seen during the * last RTT. Taking the min filters out the effects * of delayed ACKs, at the cost of noticing congestion * a bit later. */ rtt = yeah->vegas.minRTT; /* Compute excess number of packets above bandwidth * Avoid doing full 64 bit divide. */ bw = tcp_snd_cwnd(tp); bw *= rtt - yeah->vegas.baseRTT; do_div(bw, rtt); queue = bw; if (queue > TCP_YEAH_ALPHA || rtt - yeah->vegas.baseRTT > (yeah->vegas.baseRTT / TCP_YEAH_PHY)) { if (queue > TCP_YEAH_ALPHA && tcp_snd_cwnd(tp) > yeah->reno_count) { u32 reduction = min(queue / TCP_YEAH_GAMMA , tcp_snd_cwnd(tp) >> TCP_YEAH_EPSILON); tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) - reduction); tcp_snd_cwnd_set(tp, max(tcp_snd_cwnd(tp), yeah->reno_count)); tp->snd_ssthresh = tcp_snd_cwnd(tp); } if (yeah->reno_count <= 2) yeah->reno_count = max(tcp_snd_cwnd(tp)>>1, 2U); else yeah->reno_count++; yeah->doing_reno_now = min(yeah->doing_reno_now + 1, 0xffffffU); } else { yeah->fast_count++; if (yeah->fast_count > TCP_YEAH_ZETA) { yeah->reno_count = 2; yeah->fast_count = 0; } yeah->doing_reno_now = 0; } yeah->lastQ = queue; } /* Save the extent of the current window so we can use this * at the end of the next RTT. */ yeah->vegas.beg_snd_una = yeah->vegas.beg_snd_nxt; yeah->vegas.beg_snd_nxt = tp->snd_nxt; yeah->vegas.beg_snd_cwnd = tcp_snd_cwnd(tp); /* Wipe the slate clean for the next RTT. */ yeah->vegas.cntRTT = 0; yeah->vegas.minRTT = 0x7fffffff; } } static u32 tcp_yeah_ssthresh(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct yeah *yeah = inet_csk_ca(sk); u32 reduction; if (yeah->doing_reno_now < TCP_YEAH_RHO) { reduction = yeah->lastQ; reduction = min(reduction, max(tcp_snd_cwnd(tp)>>1, 2U)); reduction = max(reduction, tcp_snd_cwnd(tp) >> TCP_YEAH_DELTA); } else reduction = max(tcp_snd_cwnd(tp)>>1, 2U); yeah->fast_count = 0; yeah->reno_count = max(yeah->reno_count>>1, 2U); return max_t(int, tcp_snd_cwnd(tp) - reduction, 2); } static struct tcp_congestion_ops tcp_yeah __read_mostly = { .init = tcp_yeah_init, .ssthresh = tcp_yeah_ssthresh, .undo_cwnd = tcp_reno_undo_cwnd, .cong_avoid = tcp_yeah_cong_avoid, .set_state = tcp_vegas_state, .cwnd_event = tcp_vegas_cwnd_event, .get_info = tcp_vegas_get_info, .pkts_acked = tcp_vegas_pkts_acked, .owner = THIS_MODULE, .name = "yeah", }; static int __init tcp_yeah_register(void) { BUILD_BUG_ON(sizeof(struct yeah) > ICSK_CA_PRIV_SIZE); tcp_register_congestion_control(&tcp_yeah); return 0; } static void __exit tcp_yeah_unregister(void) { tcp_unregister_congestion_control(&tcp_yeah); } module_init(tcp_yeah_register); module_exit(tcp_yeah_unregister); MODULE_AUTHOR("Angelo P. Castellani"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("YeAH TCP");
linux-master
net/ipv4/tcp_yeah.c
// SPDX-License-Identifier: GPL-2.0 /* * xfrm4_input.c * * Changes: * YOSHIFUJI Hideaki @USAGI * Split up af-specific portion * Derek Atkins <[email protected]> * Add Encapsulation support * */ #include <linux/slab.h> #include <linux/module.h> #include <linux/string.h> #include <linux/netfilter.h> #include <linux/netfilter_ipv4.h> #include <net/ip.h> #include <net/xfrm.h> static int xfrm4_rcv_encap_finish2(struct net *net, struct sock *sk, struct sk_buff *skb) { return dst_input(skb); } static inline int xfrm4_rcv_encap_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { if (!skb_dst(skb)) { const struct iphdr *iph = ip_hdr(skb); if (ip_route_input_noref(skb, iph->daddr, iph->saddr, iph->tos, skb->dev)) goto drop; } if (xfrm_trans_queue(skb, xfrm4_rcv_encap_finish2)) goto drop; return 0; drop: kfree_skb(skb); return NET_RX_DROP; } int xfrm4_transport_finish(struct sk_buff *skb, int async) { struct xfrm_offload *xo = xfrm_offload(skb); struct iphdr *iph = ip_hdr(skb); iph->protocol = XFRM_MODE_SKB_CB(skb)->protocol; #ifndef CONFIG_NETFILTER if (!async) return -iph->protocol; #endif __skb_push(skb, skb->data - skb_network_header(skb)); iph->tot_len = htons(skb->len); ip_send_check(iph); if (xo && (xo->flags & XFRM_GRO)) { skb_mac_header_rebuild(skb); skb_reset_transport_header(skb); return 0; } NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING, dev_net(skb->dev), NULL, skb, skb->dev, NULL, xfrm4_rcv_encap_finish); return 0; } /* If it's a keepalive packet, then just eat it. * If it's an encapsulated packet, then pass it to the * IPsec xfrm input. * Returns 0 if skb passed to xfrm or was dropped. * Returns >0 if skb should be passed to UDP. * Returns <0 if skb should be resubmitted (-ret is protocol) */ int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb) { struct udp_sock *up = udp_sk(sk); struct udphdr *uh; struct iphdr *iph; int iphlen, len; __u8 *udpdata; __be32 *udpdata32; __u16 encap_type = up->encap_type; /* if this is not encapsulated socket, then just return now */ if (!encap_type) return 1; /* If this is a paged skb, make sure we pull up * whatever data we need to look at. */ len = skb->len - sizeof(struct udphdr); if (!pskb_may_pull(skb, sizeof(struct udphdr) + min(len, 8))) return 1; /* Now we can get the pointers */ uh = udp_hdr(skb); udpdata = (__u8 *)uh + sizeof(struct udphdr); udpdata32 = (__be32 *)udpdata; switch (encap_type) { default: case UDP_ENCAP_ESPINUDP: /* Check if this is a keepalive packet. If so, eat it. */ if (len == 1 && udpdata[0] == 0xff) { goto drop; } else if (len > sizeof(struct ip_esp_hdr) && udpdata32[0] != 0) { /* ESP Packet without Non-ESP header */ len = sizeof(struct udphdr); } else /* Must be an IKE packet.. pass it through */ return 1; break; case UDP_ENCAP_ESPINUDP_NON_IKE: /* Check if this is a keepalive packet. If so, eat it. */ if (len == 1 && udpdata[0] == 0xff) { goto drop; } else if (len > 2 * sizeof(u32) + sizeof(struct ip_esp_hdr) && udpdata32[0] == 0 && udpdata32[1] == 0) { /* ESP Packet with Non-IKE marker */ len = sizeof(struct udphdr) + 2 * sizeof(u32); } else /* Must be an IKE packet.. pass it through */ return 1; break; } /* At this point we are sure that this is an ESPinUDP packet, * so we need to remove 'len' bytes from the packet (the UDP * header and optional ESP marker bytes) and then modify the * protocol to ESP, and then call into the transform receiver. */ if (skb_unclone(skb, GFP_ATOMIC)) goto drop; /* Now we can update and verify the packet length... */ iph = ip_hdr(skb); iphlen = iph->ihl << 2; iph->tot_len = htons(ntohs(iph->tot_len) - len); if (skb->len < iphlen + len) { /* packet is too small!?! */ goto drop; } /* pull the data buffer up to the ESP header and set the * transport header to point to ESP. Keep UDP on the stack * for later. */ __skb_pull(skb, len); skb_reset_transport_header(skb); /* process ESP */ return xfrm4_rcv_encap(skb, IPPROTO_ESP, 0, encap_type); drop: kfree_skb(skb); return 0; } EXPORT_SYMBOL(xfrm4_udp_encap_rcv); int xfrm4_rcv(struct sk_buff *skb) { return xfrm4_rcv_spi(skb, ip_hdr(skb)->protocol, 0); } EXPORT_SYMBOL(xfrm4_rcv);
linux-master
net/ipv4/xfrm4_input.c
// SPDX-License-Identifier: GPL-2.0-only #include <linux/module.h> #include <linux/errno.h> #include <linux/socket.h> #include <linux/kernel.h> #include <net/dst_metadata.h> #include <net/udp.h> #include <net/udp_tunnel.h> int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg, struct socket **sockp) { int err; struct socket *sock = NULL; struct sockaddr_in udp_addr; err = sock_create_kern(net, AF_INET, SOCK_DGRAM, 0, &sock); if (err < 0) goto error; if (cfg->bind_ifindex) { err = sock_bindtoindex(sock->sk, cfg->bind_ifindex, true); if (err < 0) goto error; } udp_addr.sin_family = AF_INET; udp_addr.sin_addr = cfg->local_ip; udp_addr.sin_port = cfg->local_udp_port; err = kernel_bind(sock, (struct sockaddr *)&udp_addr, sizeof(udp_addr)); if (err < 0) goto error; if (cfg->peer_udp_port) { udp_addr.sin_family = AF_INET; udp_addr.sin_addr = cfg->peer_ip; udp_addr.sin_port = cfg->peer_udp_port; err = kernel_connect(sock, (struct sockaddr *)&udp_addr, sizeof(udp_addr), 0); if (err < 0) goto error; } sock->sk->sk_no_check_tx = !cfg->use_udp_checksums; *sockp = sock; return 0; error: if (sock) { kernel_sock_shutdown(sock, SHUT_RDWR); sock_release(sock); } *sockp = NULL; return err; } EXPORT_SYMBOL(udp_sock_create4); void setup_udp_tunnel_sock(struct net *net, struct socket *sock, struct udp_tunnel_sock_cfg *cfg) { struct sock *sk = sock->sk; /* Disable multicast loopback */ inet_clear_bit(MC_LOOP, sk); /* Enable CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion */ inet_inc_convert_csum(sk); rcu_assign_sk_user_data(sk, cfg->sk_user_data); udp_sk(sk)->encap_type = cfg->encap_type; udp_sk(sk)->encap_rcv = cfg->encap_rcv; udp_sk(sk)->encap_err_rcv = cfg->encap_err_rcv; udp_sk(sk)->encap_err_lookup = cfg->encap_err_lookup; udp_sk(sk)->encap_destroy = cfg->encap_destroy; udp_sk(sk)->gro_receive = cfg->gro_receive; udp_sk(sk)->gro_complete = cfg->gro_complete; udp_tunnel_encap_enable(sock); } EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock); void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock, unsigned short type) { struct sock *sk = sock->sk; struct udp_tunnel_info ti; ti.type = type; ti.sa_family = sk->sk_family; ti.port = inet_sk(sk)->inet_sport; udp_tunnel_nic_add_port(dev, &ti); } EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port); void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock, unsigned short type) { struct sock *sk = sock->sk; struct udp_tunnel_info ti; ti.type = type; ti.sa_family = sk->sk_family; ti.port = inet_sk(sk)->inet_sport; udp_tunnel_nic_del_port(dev, &ti); } EXPORT_SYMBOL_GPL(udp_tunnel_drop_rx_port); /* Notify netdevs that UDP port started listening */ void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type) { struct sock *sk = sock->sk; struct net *net = sock_net(sk); struct udp_tunnel_info ti; struct net_device *dev; ti.type = type; ti.sa_family = sk->sk_family; ti.port = inet_sk(sk)->inet_sport; rcu_read_lock(); for_each_netdev_rcu(net, dev) { udp_tunnel_nic_add_port(dev, &ti); } rcu_read_unlock(); } EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port); /* Notify netdevs that UDP port is no more listening */ void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type) { struct sock *sk = sock->sk; struct net *net = sock_net(sk); struct udp_tunnel_info ti; struct net_device *dev; ti.type = type; ti.sa_family = sk->sk_family; ti.port = inet_sk(sk)->inet_sport; rcu_read_lock(); for_each_netdev_rcu(net, dev) { udp_tunnel_nic_del_port(dev, &ti); } rcu_read_unlock(); } EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port); void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb, __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df, __be16 src_port, __be16 dst_port, bool xnet, bool nocheck) { struct udphdr *uh; __skb_push(skb, sizeof(*uh)); skb_reset_transport_header(skb); uh = udp_hdr(skb); uh->dest = dst_port; uh->source = src_port; uh->len = htons(skb->len); memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); udp_set_csum(nocheck, skb, src, dst, skb->len); iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet); } EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb); void udp_tunnel_sock_release(struct socket *sock) { rcu_assign_sk_user_data(sock->sk, NULL); synchronize_rcu(); kernel_sock_shutdown(sock, SHUT_RDWR); sock_release(sock); } EXPORT_SYMBOL_GPL(udp_tunnel_sock_release); struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family, __be16 flags, __be64 tunnel_id, int md_size) { struct metadata_dst *tun_dst; struct ip_tunnel_info *info; if (family == AF_INET) tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size); else tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size); if (!tun_dst) return NULL; info = &tun_dst->u.tun_info; info->key.tp_src = udp_hdr(skb)->source; info->key.tp_dst = udp_hdr(skb)->dest; if (udp_hdr(skb)->check) info->key.tun_flags |= TUNNEL_CSUM; return tun_dst; } EXPORT_SYMBOL_GPL(udp_tun_rx_dst); MODULE_LICENSE("GPL");
linux-master
net/ipv4/udp_tunnel_core.c
// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2013 Nicira, Inc. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/types.h> #include <linux/kernel.h> #include <linux/skbuff.h> #include <linux/netdevice.h> #include <linux/in.h> #include <linux/if_arp.h> #include <linux/init.h> #include <linux/in6.h> #include <linux/inetdevice.h> #include <linux/netfilter_ipv4.h> #include <linux/etherdevice.h> #include <linux/if_ether.h> #include <linux/if_vlan.h> #include <linux/static_key.h> #include <net/ip.h> #include <net/icmp.h> #include <net/protocol.h> #include <net/ip_tunnels.h> #include <net/ip6_tunnel.h> #include <net/ip6_checksum.h> #include <net/arp.h> #include <net/checksum.h> #include <net/dsfield.h> #include <net/inet_ecn.h> #include <net/xfrm.h> #include <net/net_namespace.h> #include <net/netns/generic.h> #include <net/rtnetlink.h> #include <net/dst_metadata.h> #include <net/geneve.h> #include <net/vxlan.h> #include <net/erspan.h> const struct ip_tunnel_encap_ops __rcu * iptun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; EXPORT_SYMBOL(iptun_encaps); const struct ip6_tnl_encap_ops __rcu * ip6tun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; EXPORT_SYMBOL(ip6tun_encaps); void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, __be32 src, __be32 dst, __u8 proto, __u8 tos, __u8 ttl, __be16 df, bool xnet) { int pkt_len = skb->len - skb_inner_network_offset(skb); struct net *net = dev_net(rt->dst.dev); struct net_device *dev = skb->dev; struct iphdr *iph; int err; skb_scrub_packet(skb, xnet); skb_clear_hash_if_not_l4(skb); skb_dst_set(skb, &rt->dst); memset(IPCB(skb), 0, sizeof(*IPCB(skb))); /* Push down and install the IP header. */ skb_push(skb, sizeof(struct iphdr)); skb_reset_network_header(skb); iph = ip_hdr(skb); iph->version = 4; iph->ihl = sizeof(struct iphdr) >> 2; iph->frag_off = ip_mtu_locked(&rt->dst) ? 0 : df; iph->protocol = proto; iph->tos = tos; iph->daddr = dst; iph->saddr = src; iph->ttl = ttl; __ip_select_ident(net, iph, skb_shinfo(skb)->gso_segs ?: 1); err = ip_local_out(net, sk, skb); if (dev) { if (unlikely(net_xmit_eval(err))) pkt_len = 0; iptunnel_xmit_stats(dev, pkt_len); } } EXPORT_SYMBOL_GPL(iptunnel_xmit); int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto, bool raw_proto, bool xnet) { if (unlikely(!pskb_may_pull(skb, hdr_len))) return -ENOMEM; skb_pull_rcsum(skb, hdr_len); if (!raw_proto && inner_proto == htons(ETH_P_TEB)) { struct ethhdr *eh; if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) return -ENOMEM; eh = (struct ethhdr *)skb->data; if (likely(eth_proto_is_802_3(eh->h_proto))) skb->protocol = eh->h_proto; else skb->protocol = htons(ETH_P_802_2); } else { skb->protocol = inner_proto; } skb_clear_hash_if_not_l4(skb); __vlan_hwaccel_clear_tag(skb); skb_set_queue_mapping(skb, 0); skb_scrub_packet(skb, xnet); return iptunnel_pull_offloads(skb); } EXPORT_SYMBOL_GPL(__iptunnel_pull_header); struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, gfp_t flags) { struct metadata_dst *res; struct ip_tunnel_info *dst, *src; if (!md || md->type != METADATA_IP_TUNNEL || md->u.tun_info.mode & IP_TUNNEL_INFO_TX) return NULL; src = &md->u.tun_info; res = metadata_dst_alloc(src->options_len, METADATA_IP_TUNNEL, flags); if (!res) return NULL; dst = &res->u.tun_info; dst->key.tun_id = src->key.tun_id; if (src->mode & IP_TUNNEL_INFO_IPV6) memcpy(&dst->key.u.ipv6.dst, &src->key.u.ipv6.src, sizeof(struct in6_addr)); else dst->key.u.ipv4.dst = src->key.u.ipv4.src; dst->key.tun_flags = src->key.tun_flags; dst->mode = src->mode | IP_TUNNEL_INFO_TX; ip_tunnel_info_opts_set(dst, ip_tunnel_info_opts(src), src->options_len, 0); return res; } EXPORT_SYMBOL_GPL(iptunnel_metadata_reply); int iptunnel_handle_offloads(struct sk_buff *skb, int gso_type_mask) { int err; if (likely(!skb->encapsulation)) { skb_reset_inner_headers(skb); skb->encapsulation = 1; } if (skb_is_gso(skb)) { err = skb_header_unclone(skb, GFP_ATOMIC); if (unlikely(err)) return err; skb_shinfo(skb)->gso_type |= gso_type_mask; return 0; } if (skb->ip_summed != CHECKSUM_PARTIAL) { skb->ip_summed = CHECKSUM_NONE; /* We clear encapsulation here to prevent badly-written * drivers potentially deciding to offload an inner checksum * if we set CHECKSUM_PARTIAL on the outer header. * This should go away when the drivers are all fixed. */ skb->encapsulation = 0; } return 0; } EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); /** * iptunnel_pmtud_build_icmp() - Build ICMP error message for PMTUD * @skb: Original packet with L2 header * @mtu: MTU value for ICMP error * * Return: length on success, negative error code if message couldn't be built. */ static int iptunnel_pmtud_build_icmp(struct sk_buff *skb, int mtu) { const struct iphdr *iph = ip_hdr(skb); struct icmphdr *icmph; struct iphdr *niph; struct ethhdr eh; int len, err; if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct iphdr))) return -EINVAL; skb_copy_bits(skb, skb_mac_offset(skb), &eh, ETH_HLEN); pskb_pull(skb, ETH_HLEN); skb_reset_network_header(skb); err = pskb_trim(skb, 576 - sizeof(*niph) - sizeof(*icmph)); if (err) return err; len = skb->len + sizeof(*icmph); err = skb_cow(skb, sizeof(*niph) + sizeof(*icmph) + ETH_HLEN); if (err) return err; icmph = skb_push(skb, sizeof(*icmph)); *icmph = (struct icmphdr) { .type = ICMP_DEST_UNREACH, .code = ICMP_FRAG_NEEDED, .checksum = 0, .un.frag.__unused = 0, .un.frag.mtu = htons(mtu), }; icmph->checksum = csum_fold(skb_checksum(skb, 0, len, 0)); skb_reset_transport_header(skb); niph = skb_push(skb, sizeof(*niph)); *niph = (struct iphdr) { .ihl = sizeof(*niph) / 4u, .version = 4, .tos = 0, .tot_len = htons(len + sizeof(*niph)), .id = 0, .frag_off = htons(IP_DF), .ttl = iph->ttl, .protocol = IPPROTO_ICMP, .saddr = iph->daddr, .daddr = iph->saddr, }; ip_send_check(niph); skb_reset_network_header(skb); skb->ip_summed = CHECKSUM_NONE; eth_header(skb, skb->dev, ntohs(eh.h_proto), eh.h_source, eh.h_dest, 0); skb_reset_mac_header(skb); return skb->len; } /** * iptunnel_pmtud_check_icmp() - Trigger ICMP reply if needed and allowed * @skb: Buffer being sent by encapsulation, L2 headers expected * @mtu: Network MTU for path * * Return: 0 for no ICMP reply, length if built, negative value on error. */ static int iptunnel_pmtud_check_icmp(struct sk_buff *skb, int mtu) { const struct icmphdr *icmph = icmp_hdr(skb); const struct iphdr *iph = ip_hdr(skb); if (mtu < 576 || iph->frag_off != htons(IP_DF)) return 0; if (ipv4_is_lbcast(iph->daddr) || ipv4_is_multicast(iph->daddr) || ipv4_is_zeronet(iph->saddr) || ipv4_is_loopback(iph->saddr) || ipv4_is_lbcast(iph->saddr) || ipv4_is_multicast(iph->saddr)) return 0; if (iph->protocol == IPPROTO_ICMP && icmp_is_err(icmph->type)) return 0; return iptunnel_pmtud_build_icmp(skb, mtu); } #if IS_ENABLED(CONFIG_IPV6) /** * iptunnel_pmtud_build_icmpv6() - Build ICMPv6 error message for PMTUD * @skb: Original packet with L2 header * @mtu: MTU value for ICMPv6 error * * Return: length on success, negative error code if message couldn't be built. */ static int iptunnel_pmtud_build_icmpv6(struct sk_buff *skb, int mtu) { const struct ipv6hdr *ip6h = ipv6_hdr(skb); struct icmp6hdr *icmp6h; struct ipv6hdr *nip6h; struct ethhdr eh; int len, err; __wsum csum; if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct ipv6hdr))) return -EINVAL; skb_copy_bits(skb, skb_mac_offset(skb), &eh, ETH_HLEN); pskb_pull(skb, ETH_HLEN); skb_reset_network_header(skb); err = pskb_trim(skb, IPV6_MIN_MTU - sizeof(*nip6h) - sizeof(*icmp6h)); if (err) return err; len = skb->len + sizeof(*icmp6h); err = skb_cow(skb, sizeof(*nip6h) + sizeof(*icmp6h) + ETH_HLEN); if (err) return err; icmp6h = skb_push(skb, sizeof(*icmp6h)); *icmp6h = (struct icmp6hdr) { .icmp6_type = ICMPV6_PKT_TOOBIG, .icmp6_code = 0, .icmp6_cksum = 0, .icmp6_mtu = htonl(mtu), }; skb_reset_transport_header(skb); nip6h = skb_push(skb, sizeof(*nip6h)); *nip6h = (struct ipv6hdr) { .priority = 0, .version = 6, .flow_lbl = { 0 }, .payload_len = htons(len), .nexthdr = IPPROTO_ICMPV6, .hop_limit = ip6h->hop_limit, .saddr = ip6h->daddr, .daddr = ip6h->saddr, }; skb_reset_network_header(skb); csum = csum_partial(icmp6h, len, 0); icmp6h->icmp6_cksum = csum_ipv6_magic(&nip6h->saddr, &nip6h->daddr, len, IPPROTO_ICMPV6, csum); skb->ip_summed = CHECKSUM_NONE; eth_header(skb, skb->dev, ntohs(eh.h_proto), eh.h_source, eh.h_dest, 0); skb_reset_mac_header(skb); return skb->len; } /** * iptunnel_pmtud_check_icmpv6() - Trigger ICMPv6 reply if needed and allowed * @skb: Buffer being sent by encapsulation, L2 headers expected * @mtu: Network MTU for path * * Return: 0 for no ICMPv6 reply, length if built, negative value on error. */ static int iptunnel_pmtud_check_icmpv6(struct sk_buff *skb, int mtu) { const struct ipv6hdr *ip6h = ipv6_hdr(skb); int stype = ipv6_addr_type(&ip6h->saddr); u8 proto = ip6h->nexthdr; __be16 frag_off; int offset; if (mtu < IPV6_MIN_MTU) return 0; if (stype == IPV6_ADDR_ANY || stype == IPV6_ADDR_MULTICAST || stype == IPV6_ADDR_LOOPBACK) return 0; offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &proto, &frag_off); if (offset < 0 || (frag_off & htons(~0x7))) return 0; if (proto == IPPROTO_ICMPV6) { struct icmp6hdr *icmp6h; if (!pskb_may_pull(skb, skb_network_header(skb) + offset + 1 - skb->data)) return 0; icmp6h = (struct icmp6hdr *)(skb_network_header(skb) + offset); if (icmpv6_is_err(icmp6h->icmp6_type) || icmp6h->icmp6_type == NDISC_REDIRECT) return 0; } return iptunnel_pmtud_build_icmpv6(skb, mtu); } #endif /* IS_ENABLED(CONFIG_IPV6) */ /** * skb_tunnel_check_pmtu() - Check, update PMTU and trigger ICMP reply as needed * @skb: Buffer being sent by encapsulation, L2 headers expected * @encap_dst: Destination for tunnel encapsulation (outer IP) * @headroom: Encapsulation header size, bytes * @reply: Build matching ICMP or ICMPv6 message as a result * * L2 tunnel implementations that can carry IP and can be directly bridged * (currently UDP tunnels) can't always rely on IP forwarding paths to handle * PMTU discovery. In the bridged case, ICMP or ICMPv6 messages need to be built * based on payload and sent back by the encapsulation itself. * * For routable interfaces, we just need to update the PMTU for the destination. * * Return: 0 if ICMP error not needed, length if built, negative value on error */ int skb_tunnel_check_pmtu(struct sk_buff *skb, struct dst_entry *encap_dst, int headroom, bool reply) { u32 mtu = dst_mtu(encap_dst) - headroom; if ((skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu)) || (!skb_is_gso(skb) && (skb->len - skb_network_offset(skb)) <= mtu)) return 0; skb_dst_update_pmtu_no_confirm(skb, mtu); if (!reply || skb->pkt_type == PACKET_HOST) return 0; if (skb->protocol == htons(ETH_P_IP)) return iptunnel_pmtud_check_icmp(skb, mtu); #if IS_ENABLED(CONFIG_IPV6) if (skb->protocol == htons(ETH_P_IPV6)) return iptunnel_pmtud_check_icmpv6(skb, mtu); #endif return 0; } EXPORT_SYMBOL(skb_tunnel_check_pmtu); static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = { [LWTUNNEL_IP_UNSPEC] = { .strict_start_type = LWTUNNEL_IP_OPTS }, [LWTUNNEL_IP_ID] = { .type = NLA_U64 }, [LWTUNNEL_IP_DST] = { .type = NLA_U32 }, [LWTUNNEL_IP_SRC] = { .type = NLA_U32 }, [LWTUNNEL_IP_TTL] = { .type = NLA_U8 }, [LWTUNNEL_IP_TOS] = { .type = NLA_U8 }, [LWTUNNEL_IP_FLAGS] = { .type = NLA_U16 }, [LWTUNNEL_IP_OPTS] = { .type = NLA_NESTED }, }; static const struct nla_policy ip_opts_policy[LWTUNNEL_IP_OPTS_MAX + 1] = { [LWTUNNEL_IP_OPTS_GENEVE] = { .type = NLA_NESTED }, [LWTUNNEL_IP_OPTS_VXLAN] = { .type = NLA_NESTED }, [LWTUNNEL_IP_OPTS_ERSPAN] = { .type = NLA_NESTED }, }; static const struct nla_policy geneve_opt_policy[LWTUNNEL_IP_OPT_GENEVE_MAX + 1] = { [LWTUNNEL_IP_OPT_GENEVE_CLASS] = { .type = NLA_U16 }, [LWTUNNEL_IP_OPT_GENEVE_TYPE] = { .type = NLA_U8 }, [LWTUNNEL_IP_OPT_GENEVE_DATA] = { .type = NLA_BINARY, .len = 128 }, }; static const struct nla_policy vxlan_opt_policy[LWTUNNEL_IP_OPT_VXLAN_MAX + 1] = { [LWTUNNEL_IP_OPT_VXLAN_GBP] = { .type = NLA_U32 }, }; static const struct nla_policy erspan_opt_policy[LWTUNNEL_IP_OPT_ERSPAN_MAX + 1] = { [LWTUNNEL_IP_OPT_ERSPAN_VER] = { .type = NLA_U8 }, [LWTUNNEL_IP_OPT_ERSPAN_INDEX] = { .type = NLA_U32 }, [LWTUNNEL_IP_OPT_ERSPAN_DIR] = { .type = NLA_U8 }, [LWTUNNEL_IP_OPT_ERSPAN_HWID] = { .type = NLA_U8 }, }; static int ip_tun_parse_opts_geneve(struct nlattr *attr, struct ip_tunnel_info *info, int opts_len, struct netlink_ext_ack *extack) { struct nlattr *tb[LWTUNNEL_IP_OPT_GENEVE_MAX + 1]; int data_len, err; err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_GENEVE_MAX, attr, geneve_opt_policy, extack); if (err) return err; if (!tb[LWTUNNEL_IP_OPT_GENEVE_CLASS] || !tb[LWTUNNEL_IP_OPT_GENEVE_TYPE] || !tb[LWTUNNEL_IP_OPT_GENEVE_DATA]) return -EINVAL; attr = tb[LWTUNNEL_IP_OPT_GENEVE_DATA]; data_len = nla_len(attr); if (data_len % 4) return -EINVAL; if (info) { struct geneve_opt *opt = ip_tunnel_info_opts(info) + opts_len; memcpy(opt->opt_data, nla_data(attr), data_len); opt->length = data_len / 4; attr = tb[LWTUNNEL_IP_OPT_GENEVE_CLASS]; opt->opt_class = nla_get_be16(attr); attr = tb[LWTUNNEL_IP_OPT_GENEVE_TYPE]; opt->type = nla_get_u8(attr); info->key.tun_flags |= TUNNEL_GENEVE_OPT; } return sizeof(struct geneve_opt) + data_len; } static int ip_tun_parse_opts_vxlan(struct nlattr *attr, struct ip_tunnel_info *info, int opts_len, struct netlink_ext_ack *extack) { struct nlattr *tb[LWTUNNEL_IP_OPT_VXLAN_MAX + 1]; int err; err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_VXLAN_MAX, attr, vxlan_opt_policy, extack); if (err) return err; if (!tb[LWTUNNEL_IP_OPT_VXLAN_GBP]) return -EINVAL; if (info) { struct vxlan_metadata *md = ip_tunnel_info_opts(info) + opts_len; attr = tb[LWTUNNEL_IP_OPT_VXLAN_GBP]; md->gbp = nla_get_u32(attr); md->gbp &= VXLAN_GBP_MASK; info->key.tun_flags |= TUNNEL_VXLAN_OPT; } return sizeof(struct vxlan_metadata); } static int ip_tun_parse_opts_erspan(struct nlattr *attr, struct ip_tunnel_info *info, int opts_len, struct netlink_ext_ack *extack) { struct nlattr *tb[LWTUNNEL_IP_OPT_ERSPAN_MAX + 1]; int err; u8 ver; err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_ERSPAN_MAX, attr, erspan_opt_policy, extack); if (err) return err; if (!tb[LWTUNNEL_IP_OPT_ERSPAN_VER]) return -EINVAL; ver = nla_get_u8(tb[LWTUNNEL_IP_OPT_ERSPAN_VER]); if (ver == 1) { if (!tb[LWTUNNEL_IP_OPT_ERSPAN_INDEX]) return -EINVAL; } else if (ver == 2) { if (!tb[LWTUNNEL_IP_OPT_ERSPAN_DIR] || !tb[LWTUNNEL_IP_OPT_ERSPAN_HWID]) return -EINVAL; } else { return -EINVAL; } if (info) { struct erspan_metadata *md = ip_tunnel_info_opts(info) + opts_len; md->version = ver; if (ver == 1) { attr = tb[LWTUNNEL_IP_OPT_ERSPAN_INDEX]; md->u.index = nla_get_be32(attr); } else { attr = tb[LWTUNNEL_IP_OPT_ERSPAN_DIR]; md->u.md2.dir = nla_get_u8(attr); attr = tb[LWTUNNEL_IP_OPT_ERSPAN_HWID]; set_hwid(&md->u.md2, nla_get_u8(attr)); } info->key.tun_flags |= TUNNEL_ERSPAN_OPT; } return sizeof(struct erspan_metadata); } static int ip_tun_parse_opts(struct nlattr *attr, struct ip_tunnel_info *info, struct netlink_ext_ack *extack) { int err, rem, opt_len, opts_len = 0; struct nlattr *nla; __be16 type = 0; if (!attr) return 0; err = nla_validate(nla_data(attr), nla_len(attr), LWTUNNEL_IP_OPTS_MAX, ip_opts_policy, extack); if (err) return err; nla_for_each_attr(nla, nla_data(attr), nla_len(attr), rem) { switch (nla_type(nla)) { case LWTUNNEL_IP_OPTS_GENEVE: if (type && type != TUNNEL_GENEVE_OPT) return -EINVAL; opt_len = ip_tun_parse_opts_geneve(nla, info, opts_len, extack); if (opt_len < 0) return opt_len; opts_len += opt_len; if (opts_len > IP_TUNNEL_OPTS_MAX) return -EINVAL; type = TUNNEL_GENEVE_OPT; break; case LWTUNNEL_IP_OPTS_VXLAN: if (type) return -EINVAL; opt_len = ip_tun_parse_opts_vxlan(nla, info, opts_len, extack); if (opt_len < 0) return opt_len; opts_len += opt_len; type = TUNNEL_VXLAN_OPT; break; case LWTUNNEL_IP_OPTS_ERSPAN: if (type) return -EINVAL; opt_len = ip_tun_parse_opts_erspan(nla, info, opts_len, extack); if (opt_len < 0) return opt_len; opts_len += opt_len; type = TUNNEL_ERSPAN_OPT; break; default: return -EINVAL; } } return opts_len; } static int ip_tun_get_optlen(struct nlattr *attr, struct netlink_ext_ack *extack) { return ip_tun_parse_opts(attr, NULL, extack); } static int ip_tun_set_opts(struct nlattr *attr, struct ip_tunnel_info *info, struct netlink_ext_ack *extack) { return ip_tun_parse_opts(attr, info, extack); } static int ip_tun_build_state(struct net *net, struct nlattr *attr, unsigned int family, const void *cfg, struct lwtunnel_state **ts, struct netlink_ext_ack *extack) { struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; struct lwtunnel_state *new_state; struct ip_tunnel_info *tun_info; int err, opt_len; err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_MAX, attr, ip_tun_policy, extack); if (err < 0) return err; opt_len = ip_tun_get_optlen(tb[LWTUNNEL_IP_OPTS], extack); if (opt_len < 0) return opt_len; new_state = lwtunnel_state_alloc(sizeof(*tun_info) + opt_len); if (!new_state) return -ENOMEM; new_state->type = LWTUNNEL_ENCAP_IP; tun_info = lwt_tun_info(new_state); err = ip_tun_set_opts(tb[LWTUNNEL_IP_OPTS], tun_info, extack); if (err < 0) { lwtstate_free(new_state); return err; } #ifdef CONFIG_DST_CACHE err = dst_cache_init(&tun_info->dst_cache, GFP_KERNEL); if (err) { lwtstate_free(new_state); return err; } #endif if (tb[LWTUNNEL_IP_ID]) tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP_ID]); if (tb[LWTUNNEL_IP_DST]) tun_info->key.u.ipv4.dst = nla_get_in_addr(tb[LWTUNNEL_IP_DST]); if (tb[LWTUNNEL_IP_SRC]) tun_info->key.u.ipv4.src = nla_get_in_addr(tb[LWTUNNEL_IP_SRC]); if (tb[LWTUNNEL_IP_TTL]) tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]); if (tb[LWTUNNEL_IP_TOS]) tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]); if (tb[LWTUNNEL_IP_FLAGS]) tun_info->key.tun_flags |= (nla_get_be16(tb[LWTUNNEL_IP_FLAGS]) & ~TUNNEL_OPTIONS_PRESENT); tun_info->mode = IP_TUNNEL_INFO_TX; tun_info->options_len = opt_len; *ts = new_state; return 0; } static void ip_tun_destroy_state(struct lwtunnel_state *lwtstate) { #ifdef CONFIG_DST_CACHE struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); dst_cache_destroy(&tun_info->dst_cache); #endif } static int ip_tun_fill_encap_opts_geneve(struct sk_buff *skb, struct ip_tunnel_info *tun_info) { struct geneve_opt *opt; struct nlattr *nest; int offset = 0; nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_GENEVE); if (!nest) return -ENOMEM; while (tun_info->options_len > offset) { opt = ip_tunnel_info_opts(tun_info) + offset; if (nla_put_be16(skb, LWTUNNEL_IP_OPT_GENEVE_CLASS, opt->opt_class) || nla_put_u8(skb, LWTUNNEL_IP_OPT_GENEVE_TYPE, opt->type) || nla_put(skb, LWTUNNEL_IP_OPT_GENEVE_DATA, opt->length * 4, opt->opt_data)) { nla_nest_cancel(skb, nest); return -ENOMEM; } offset += sizeof(*opt) + opt->length * 4; } nla_nest_end(skb, nest); return 0; } static int ip_tun_fill_encap_opts_vxlan(struct sk_buff *skb, struct ip_tunnel_info *tun_info) { struct vxlan_metadata *md; struct nlattr *nest; nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_VXLAN); if (!nest) return -ENOMEM; md = ip_tunnel_info_opts(tun_info); if (nla_put_u32(skb, LWTUNNEL_IP_OPT_VXLAN_GBP, md->gbp)) { nla_nest_cancel(skb, nest); return -ENOMEM; } nla_nest_end(skb, nest); return 0; } static int ip_tun_fill_encap_opts_erspan(struct sk_buff *skb, struct ip_tunnel_info *tun_info) { struct erspan_metadata *md; struct nlattr *nest; nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_ERSPAN); if (!nest) return -ENOMEM; md = ip_tunnel_info_opts(tun_info); if (nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_VER, md->version)) goto err; if (md->version == 1 && nla_put_be32(skb, LWTUNNEL_IP_OPT_ERSPAN_INDEX, md->u.index)) goto err; if (md->version == 2 && (nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_DIR, md->u.md2.dir) || nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_HWID, get_hwid(&md->u.md2)))) goto err; nla_nest_end(skb, nest); return 0; err: nla_nest_cancel(skb, nest); return -ENOMEM; } static int ip_tun_fill_encap_opts(struct sk_buff *skb, int type, struct ip_tunnel_info *tun_info) { struct nlattr *nest; int err = 0; if (!(tun_info->key.tun_flags & TUNNEL_OPTIONS_PRESENT)) return 0; nest = nla_nest_start_noflag(skb, type); if (!nest) return -ENOMEM; if (tun_info->key.tun_flags & TUNNEL_GENEVE_OPT) err = ip_tun_fill_encap_opts_geneve(skb, tun_info); else if (tun_info->key.tun_flags & TUNNEL_VXLAN_OPT) err = ip_tun_fill_encap_opts_vxlan(skb, tun_info); else if (tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT) err = ip_tun_fill_encap_opts_erspan(skb, tun_info); if (err) { nla_nest_cancel(skb, nest); return err; } nla_nest_end(skb, nest); return 0; } static int ip_tun_fill_encap_info(struct sk_buff *skb, struct lwtunnel_state *lwtstate) { struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); if (nla_put_be64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id, LWTUNNEL_IP_PAD) || nla_put_in_addr(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) || nla_put_in_addr(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) || nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) || nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) || nla_put_be16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags) || ip_tun_fill_encap_opts(skb, LWTUNNEL_IP_OPTS, tun_info)) return -ENOMEM; return 0; } static int ip_tun_opts_nlsize(struct ip_tunnel_info *info) { int opt_len; if (!(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT)) return 0; opt_len = nla_total_size(0); /* LWTUNNEL_IP_OPTS */ if (info->key.tun_flags & TUNNEL_GENEVE_OPT) { struct geneve_opt *opt; int offset = 0; opt_len += nla_total_size(0); /* LWTUNNEL_IP_OPTS_GENEVE */ while (info->options_len > offset) { opt = ip_tunnel_info_opts(info) + offset; opt_len += nla_total_size(2) /* OPT_GENEVE_CLASS */ + nla_total_size(1) /* OPT_GENEVE_TYPE */ + nla_total_size(opt->length * 4); /* OPT_GENEVE_DATA */ offset += sizeof(*opt) + opt->length * 4; } } else if (info->key.tun_flags & TUNNEL_VXLAN_OPT) { opt_len += nla_total_size(0) /* LWTUNNEL_IP_OPTS_VXLAN */ + nla_total_size(4); /* OPT_VXLAN_GBP */ } else if (info->key.tun_flags & TUNNEL_ERSPAN_OPT) { struct erspan_metadata *md = ip_tunnel_info_opts(info); opt_len += nla_total_size(0) /* LWTUNNEL_IP_OPTS_ERSPAN */ + nla_total_size(1) /* OPT_ERSPAN_VER */ + (md->version == 1 ? nla_total_size(4) /* OPT_ERSPAN_INDEX (v1) */ : nla_total_size(1) + nla_total_size(1)); /* OPT_ERSPAN_DIR + HWID (v2) */ } return opt_len; } static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) { return nla_total_size_64bit(8) /* LWTUNNEL_IP_ID */ + nla_total_size(4) /* LWTUNNEL_IP_DST */ + nla_total_size(4) /* LWTUNNEL_IP_SRC */ + nla_total_size(1) /* LWTUNNEL_IP_TOS */ + nla_total_size(1) /* LWTUNNEL_IP_TTL */ + nla_total_size(2) /* LWTUNNEL_IP_FLAGS */ + ip_tun_opts_nlsize(lwt_tun_info(lwtstate)); /* LWTUNNEL_IP_OPTS */ } static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) { struct ip_tunnel_info *info_a = lwt_tun_info(a); struct ip_tunnel_info *info_b = lwt_tun_info(b); return memcmp(info_a, info_b, sizeof(info_a->key)) || info_a->mode != info_b->mode || info_a->options_len != info_b->options_len || memcmp(ip_tunnel_info_opts(info_a), ip_tunnel_info_opts(info_b), info_a->options_len); } static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { .build_state = ip_tun_build_state, .destroy_state = ip_tun_destroy_state, .fill_encap = ip_tun_fill_encap_info, .get_encap_size = ip_tun_encap_nlsize, .cmp_encap = ip_tun_cmp_encap, .owner = THIS_MODULE, }; static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = { [LWTUNNEL_IP6_UNSPEC] = { .strict_start_type = LWTUNNEL_IP6_OPTS }, [LWTUNNEL_IP6_ID] = { .type = NLA_U64 }, [LWTUNNEL_IP6_DST] = { .len = sizeof(struct in6_addr) }, [LWTUNNEL_IP6_SRC] = { .len = sizeof(struct in6_addr) }, [LWTUNNEL_IP6_HOPLIMIT] = { .type = NLA_U8 }, [LWTUNNEL_IP6_TC] = { .type = NLA_U8 }, [LWTUNNEL_IP6_FLAGS] = { .type = NLA_U16 }, [LWTUNNEL_IP6_OPTS] = { .type = NLA_NESTED }, }; static int ip6_tun_build_state(struct net *net, struct nlattr *attr, unsigned int family, const void *cfg, struct lwtunnel_state **ts, struct netlink_ext_ack *extack) { struct nlattr *tb[LWTUNNEL_IP6_MAX + 1]; struct lwtunnel_state *new_state; struct ip_tunnel_info *tun_info; int err, opt_len; err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP6_MAX, attr, ip6_tun_policy, extack); if (err < 0) return err; opt_len = ip_tun_get_optlen(tb[LWTUNNEL_IP6_OPTS], extack); if (opt_len < 0) return opt_len; new_state = lwtunnel_state_alloc(sizeof(*tun_info) + opt_len); if (!new_state) return -ENOMEM; new_state->type = LWTUNNEL_ENCAP_IP6; tun_info = lwt_tun_info(new_state); err = ip_tun_set_opts(tb[LWTUNNEL_IP6_OPTS], tun_info, extack); if (err < 0) { lwtstate_free(new_state); return err; } if (tb[LWTUNNEL_IP6_ID]) tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP6_ID]); if (tb[LWTUNNEL_IP6_DST]) tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]); if (tb[LWTUNNEL_IP6_SRC]) tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]); if (tb[LWTUNNEL_IP6_HOPLIMIT]) tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]); if (tb[LWTUNNEL_IP6_TC]) tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]); if (tb[LWTUNNEL_IP6_FLAGS]) tun_info->key.tun_flags |= (nla_get_be16(tb[LWTUNNEL_IP6_FLAGS]) & ~TUNNEL_OPTIONS_PRESENT); tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6; tun_info->options_len = opt_len; *ts = new_state; return 0; } static int ip6_tun_fill_encap_info(struct sk_buff *skb, struct lwtunnel_state *lwtstate) { struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); if (nla_put_be64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id, LWTUNNEL_IP6_PAD) || nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) || nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) || nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.tos) || nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.ttl) || nla_put_be16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags) || ip_tun_fill_encap_opts(skb, LWTUNNEL_IP6_OPTS, tun_info)) return -ENOMEM; return 0; } static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate) { return nla_total_size_64bit(8) /* LWTUNNEL_IP6_ID */ + nla_total_size(16) /* LWTUNNEL_IP6_DST */ + nla_total_size(16) /* LWTUNNEL_IP6_SRC */ + nla_total_size(1) /* LWTUNNEL_IP6_HOPLIMIT */ + nla_total_size(1) /* LWTUNNEL_IP6_TC */ + nla_total_size(2) /* LWTUNNEL_IP6_FLAGS */ + ip_tun_opts_nlsize(lwt_tun_info(lwtstate)); /* LWTUNNEL_IP6_OPTS */ } static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = { .build_state = ip6_tun_build_state, .fill_encap = ip6_tun_fill_encap_info, .get_encap_size = ip6_tun_encap_nlsize, .cmp_encap = ip_tun_cmp_encap, .owner = THIS_MODULE, }; void __init ip_tunnel_core_init(void) { /* If you land here, make sure whether increasing ip_tunnel_info's * options_len is a reasonable choice with its usage in front ends * (f.e., it's part of flow keys, etc). */ BUILD_BUG_ON(IP_TUNNEL_OPTS_MAX != 255); lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP); lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6); } DEFINE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt); EXPORT_SYMBOL(ip_tunnel_metadata_cnt); void ip_tunnel_need_metadata(void) { static_branch_inc(&ip_tunnel_metadata_cnt); } EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata); void ip_tunnel_unneed_metadata(void) { static_branch_dec(&ip_tunnel_metadata_cnt); } EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata); /* Returns either the correct skb->protocol value, or 0 if invalid. */ __be16 ip_tunnel_parse_protocol(const struct sk_buff *skb) { if (skb_network_header(skb) >= skb->head && (skb_network_header(skb) + sizeof(struct iphdr)) <= skb_tail_pointer(skb) && ip_hdr(skb)->version == 4) return htons(ETH_P_IP); if (skb_network_header(skb) >= skb->head && (skb_network_header(skb) + sizeof(struct ipv6hdr)) <= skb_tail_pointer(skb) && ipv6_hdr(skb)->version == 6) return htons(ETH_P_IPV6); return 0; } EXPORT_SYMBOL(ip_tunnel_parse_protocol); const struct header_ops ip_tunnel_header_ops = { .parse_protocol = ip_tunnel_parse_protocol }; EXPORT_SYMBOL(ip_tunnel_header_ops); /* This function returns true when ENCAP attributes are present in the nl msg */ bool ip_tunnel_netlink_encap_parms(struct nlattr *data[], struct ip_tunnel_encap *encap) { bool ret = false; memset(encap, 0, sizeof(*encap)); if (!data) return ret; if (data[IFLA_IPTUN_ENCAP_TYPE]) { ret = true; encap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]); } if (data[IFLA_IPTUN_ENCAP_FLAGS]) { ret = true; encap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]); } if (data[IFLA_IPTUN_ENCAP_SPORT]) { ret = true; encap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]); } if (data[IFLA_IPTUN_ENCAP_DPORT]) { ret = true; encap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]); } return ret; } EXPORT_SYMBOL_GPL(ip_tunnel_netlink_encap_parms); void ip_tunnel_netlink_parms(struct nlattr *data[], struct ip_tunnel_parm *parms) { if (data[IFLA_IPTUN_LINK]) parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); if (data[IFLA_IPTUN_LOCAL]) parms->iph.saddr = nla_get_be32(data[IFLA_IPTUN_LOCAL]); if (data[IFLA_IPTUN_REMOTE]) parms->iph.daddr = nla_get_be32(data[IFLA_IPTUN_REMOTE]); if (data[IFLA_IPTUN_TTL]) { parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]); if (parms->iph.ttl) parms->iph.frag_off = htons(IP_DF); } if (data[IFLA_IPTUN_TOS]) parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]); if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC])) parms->iph.frag_off = htons(IP_DF); if (data[IFLA_IPTUN_FLAGS]) parms->i_flags = nla_get_be16(data[IFLA_IPTUN_FLAGS]); if (data[IFLA_IPTUN_PROTO]) parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]); } EXPORT_SYMBOL_GPL(ip_tunnel_netlink_parms);
linux-master
net/ipv4/ip_tunnel_core.c
// SPDX-License-Identifier: GPL-2.0-or-later /* xfrm4_protocol.c - Generic xfrm protocol multiplexer. * * Copyright (C) 2013 secunet Security Networks AG * * Author: * Steffen Klassert <[email protected]> * * Based on: * net/ipv4/tunnel4.c */ #include <linux/init.h> #include <linux/mutex.h> #include <linux/skbuff.h> #include <net/icmp.h> #include <net/ip.h> #include <net/protocol.h> #include <net/xfrm.h> static struct xfrm4_protocol __rcu *esp4_handlers __read_mostly; static struct xfrm4_protocol __rcu *ah4_handlers __read_mostly; static struct xfrm4_protocol __rcu *ipcomp4_handlers __read_mostly; static DEFINE_MUTEX(xfrm4_protocol_mutex); static inline struct xfrm4_protocol __rcu **proto_handlers(u8 protocol) { switch (protocol) { case IPPROTO_ESP: return &esp4_handlers; case IPPROTO_AH: return &ah4_handlers; case IPPROTO_COMP: return &ipcomp4_handlers; } return NULL; } #define for_each_protocol_rcu(head, handler) \ for (handler = rcu_dereference(head); \ handler != NULL; \ handler = rcu_dereference(handler->next)) \ static int xfrm4_rcv_cb(struct sk_buff *skb, u8 protocol, int err) { int ret; struct xfrm4_protocol *handler; struct xfrm4_protocol __rcu **head = proto_handlers(protocol); if (!head) return 0; for_each_protocol_rcu(*head, handler) if ((ret = handler->cb_handler(skb, err)) <= 0) return ret; return 0; } int xfrm4_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) { int ret; struct xfrm4_protocol *handler; struct xfrm4_protocol __rcu **head = proto_handlers(nexthdr); XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; XFRM_SPI_SKB_CB(skb)->family = AF_INET; XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); if (!head) goto out; if (!skb_dst(skb)) { const struct iphdr *iph = ip_hdr(skb); if (ip_route_input_noref(skb, iph->daddr, iph->saddr, iph->tos, skb->dev)) goto drop; } for_each_protocol_rcu(*head, handler) if ((ret = handler->input_handler(skb, nexthdr, spi, encap_type)) != -EINVAL) return ret; out: icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } EXPORT_SYMBOL(xfrm4_rcv_encap); static int xfrm4_esp_rcv(struct sk_buff *skb) { int ret; struct xfrm4_protocol *handler; XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; for_each_protocol_rcu(esp4_handlers, handler) if ((ret = handler->handler(skb)) != -EINVAL) return ret; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); kfree_skb(skb); return 0; } static int xfrm4_esp_err(struct sk_buff *skb, u32 info) { struct xfrm4_protocol *handler; for_each_protocol_rcu(esp4_handlers, handler) if (!handler->err_handler(skb, info)) return 0; return -ENOENT; } static int xfrm4_ah_rcv(struct sk_buff *skb) { int ret; struct xfrm4_protocol *handler; XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; for_each_protocol_rcu(ah4_handlers, handler) if ((ret = handler->handler(skb)) != -EINVAL) return ret; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); kfree_skb(skb); return 0; } static int xfrm4_ah_err(struct sk_buff *skb, u32 info) { struct xfrm4_protocol *handler; for_each_protocol_rcu(ah4_handlers, handler) if (!handler->err_handler(skb, info)) return 0; return -ENOENT; } static int xfrm4_ipcomp_rcv(struct sk_buff *skb) { int ret; struct xfrm4_protocol *handler; XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; for_each_protocol_rcu(ipcomp4_handlers, handler) if ((ret = handler->handler(skb)) != -EINVAL) return ret; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); kfree_skb(skb); return 0; } static int xfrm4_ipcomp_err(struct sk_buff *skb, u32 info) { struct xfrm4_protocol *handler; for_each_protocol_rcu(ipcomp4_handlers, handler) if (!handler->err_handler(skb, info)) return 0; return -ENOENT; } static const struct net_protocol esp4_protocol = { .handler = xfrm4_esp_rcv, .err_handler = xfrm4_esp_err, .no_policy = 1, }; static const struct net_protocol ah4_protocol = { .handler = xfrm4_ah_rcv, .err_handler = xfrm4_ah_err, .no_policy = 1, }; static const struct net_protocol ipcomp4_protocol = { .handler = xfrm4_ipcomp_rcv, .err_handler = xfrm4_ipcomp_err, .no_policy = 1, }; static const struct xfrm_input_afinfo xfrm4_input_afinfo = { .family = AF_INET, .callback = xfrm4_rcv_cb, }; static inline const struct net_protocol *netproto(unsigned char protocol) { switch (protocol) { case IPPROTO_ESP: return &esp4_protocol; case IPPROTO_AH: return &ah4_protocol; case IPPROTO_COMP: return &ipcomp4_protocol; } return NULL; } int xfrm4_protocol_register(struct xfrm4_protocol *handler, unsigned char protocol) { struct xfrm4_protocol __rcu **pprev; struct xfrm4_protocol *t; bool add_netproto = false; int ret = -EEXIST; int priority = handler->priority; if (!proto_handlers(protocol) || !netproto(protocol)) return -EINVAL; mutex_lock(&xfrm4_protocol_mutex); if (!rcu_dereference_protected(*proto_handlers(protocol), lockdep_is_held(&xfrm4_protocol_mutex))) add_netproto = true; for (pprev = proto_handlers(protocol); (t = rcu_dereference_protected(*pprev, lockdep_is_held(&xfrm4_protocol_mutex))) != NULL; pprev = &t->next) { if (t->priority < priority) break; if (t->priority == priority) goto err; } handler->next = *pprev; rcu_assign_pointer(*pprev, handler); ret = 0; err: mutex_unlock(&xfrm4_protocol_mutex); if (add_netproto) { if (inet_add_protocol(netproto(protocol), protocol)) { pr_err("%s: can't add protocol\n", __func__); ret = -EAGAIN; } } return ret; } EXPORT_SYMBOL(xfrm4_protocol_register); int xfrm4_protocol_deregister(struct xfrm4_protocol *handler, unsigned char protocol) { struct xfrm4_protocol __rcu **pprev; struct xfrm4_protocol *t; int ret = -ENOENT; if (!proto_handlers(protocol) || !netproto(protocol)) return -EINVAL; mutex_lock(&xfrm4_protocol_mutex); for (pprev = proto_handlers(protocol); (t = rcu_dereference_protected(*pprev, lockdep_is_held(&xfrm4_protocol_mutex))) != NULL; pprev = &t->next) { if (t == handler) { *pprev = handler->next; ret = 0; break; } } if (!rcu_dereference_protected(*proto_handlers(protocol), lockdep_is_held(&xfrm4_protocol_mutex))) { if (inet_del_protocol(netproto(protocol), protocol) < 0) { pr_err("%s: can't remove protocol\n", __func__); ret = -EAGAIN; } } mutex_unlock(&xfrm4_protocol_mutex); synchronize_net(); return ret; } EXPORT_SYMBOL(xfrm4_protocol_deregister); void __init xfrm4_protocol_init(void) { xfrm_input_register_afinfo(&xfrm4_input_afinfo); }
linux-master
net/ipv4/xfrm4_protocol.c
// SPDX-License-Identifier: GPL-2.0-only /* * TCP CUBIC: Binary Increase Congestion control for TCP v2.3 * Home page: * http://netsrv.csc.ncsu.edu/twiki/bin/view/Main/BIC * This is from the implementation of CUBIC TCP in * Sangtae Ha, Injong Rhee and Lisong Xu, * "CUBIC: A New TCP-Friendly High-Speed TCP Variant" * in ACM SIGOPS Operating System Review, July 2008. * Available from: * http://netsrv.csc.ncsu.edu/export/cubic_a_new_tcp_2008.pdf * * CUBIC integrates a new slow start algorithm, called HyStart. * The details of HyStart are presented in * Sangtae Ha and Injong Rhee, * "Taming the Elephants: New TCP Slow Start", NCSU TechReport 2008. * Available from: * http://netsrv.csc.ncsu.edu/export/hystart_techreport_2008.pdf * * All testing results are available from: * http://netsrv.csc.ncsu.edu/wiki/index.php/TCP_Testing * * Unless CUBIC is enabled and congestion window is large * this behaves the same as the original Reno. */ #include <linux/mm.h> #include <linux/btf.h> #include <linux/btf_ids.h> #include <linux/module.h> #include <linux/math64.h> #include <net/tcp.h> #define BICTCP_BETA_SCALE 1024 /* Scale factor beta calculation * max_cwnd = snd_cwnd * beta */ #define BICTCP_HZ 10 /* BIC HZ 2^10 = 1024 */ /* Two methods of hybrid slow start */ #define HYSTART_ACK_TRAIN 0x1 #define HYSTART_DELAY 0x2 /* Number of delay samples for detecting the increase of delay */ #define HYSTART_MIN_SAMPLES 8 #define HYSTART_DELAY_MIN (4000U) /* 4 ms */ #define HYSTART_DELAY_MAX (16000U) /* 16 ms */ #define HYSTART_DELAY_THRESH(x) clamp(x, HYSTART_DELAY_MIN, HYSTART_DELAY_MAX) static int fast_convergence __read_mostly = 1; static int beta __read_mostly = 717; /* = 717/1024 (BICTCP_BETA_SCALE) */ static int initial_ssthresh __read_mostly; static int bic_scale __read_mostly = 41; static int tcp_friendliness __read_mostly = 1; static int hystart __read_mostly = 1; static int hystart_detect __read_mostly = HYSTART_ACK_TRAIN | HYSTART_DELAY; static int hystart_low_window __read_mostly = 16; static int hystart_ack_delta_us __read_mostly = 2000; static u32 cube_rtt_scale __read_mostly; static u32 beta_scale __read_mostly; static u64 cube_factor __read_mostly; /* Note parameters that are used for precomputing scale factors are read-only */ module_param(fast_convergence, int, 0644); MODULE_PARM_DESC(fast_convergence, "turn on/off fast convergence"); module_param(beta, int, 0644); MODULE_PARM_DESC(beta, "beta for multiplicative increase"); module_param(initial_ssthresh, int, 0644); MODULE_PARM_DESC(initial_ssthresh, "initial value of slow start threshold"); module_param(bic_scale, int, 0444); MODULE_PARM_DESC(bic_scale, "scale (scaled by 1024) value for bic function (bic_scale/1024)"); module_param(tcp_friendliness, int, 0644); MODULE_PARM_DESC(tcp_friendliness, "turn on/off tcp friendliness"); module_param(hystart, int, 0644); MODULE_PARM_DESC(hystart, "turn on/off hybrid slow start algorithm"); module_param(hystart_detect, int, 0644); MODULE_PARM_DESC(hystart_detect, "hybrid slow start detection mechanisms" " 1: packet-train 2: delay 3: both packet-train and delay"); module_param(hystart_low_window, int, 0644); MODULE_PARM_DESC(hystart_low_window, "lower bound cwnd for hybrid slow start"); module_param(hystart_ack_delta_us, int, 0644); MODULE_PARM_DESC(hystart_ack_delta_us, "spacing between ack's indicating train (usecs)"); /* BIC TCP Parameters */ struct bictcp { u32 cnt; /* increase cwnd by 1 after ACKs */ u32 last_max_cwnd; /* last maximum snd_cwnd */ u32 last_cwnd; /* the last snd_cwnd */ u32 last_time; /* time when updated last_cwnd */ u32 bic_origin_point;/* origin point of bic function */ u32 bic_K; /* time to origin point from the beginning of the current epoch */ u32 delay_min; /* min delay (usec) */ u32 epoch_start; /* beginning of an epoch */ u32 ack_cnt; /* number of acks */ u32 tcp_cwnd; /* estimated tcp cwnd */ u16 unused; u8 sample_cnt; /* number of samples to decide curr_rtt */ u8 found; /* the exit point is found? */ u32 round_start; /* beginning of each round */ u32 end_seq; /* end_seq of the round */ u32 last_ack; /* last time when the ACK spacing is close */ u32 curr_rtt; /* the minimum rtt of current round */ }; static inline void bictcp_reset(struct bictcp *ca) { memset(ca, 0, offsetof(struct bictcp, unused)); ca->found = 0; } static inline u32 bictcp_clock_us(const struct sock *sk) { return tcp_sk(sk)->tcp_mstamp; } static inline void bictcp_hystart_reset(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); ca->round_start = ca->last_ack = bictcp_clock_us(sk); ca->end_seq = tp->snd_nxt; ca->curr_rtt = ~0U; ca->sample_cnt = 0; } __bpf_kfunc static void cubictcp_init(struct sock *sk) { struct bictcp *ca = inet_csk_ca(sk); bictcp_reset(ca); if (hystart) bictcp_hystart_reset(sk); if (!hystart && initial_ssthresh) tcp_sk(sk)->snd_ssthresh = initial_ssthresh; } __bpf_kfunc static void cubictcp_cwnd_event(struct sock *sk, enum tcp_ca_event event) { if (event == CA_EVENT_TX_START) { struct bictcp *ca = inet_csk_ca(sk); u32 now = tcp_jiffies32; s32 delta; delta = now - tcp_sk(sk)->lsndtime; /* We were application limited (idle) for a while. * Shift epoch_start to keep cwnd growth to cubic curve. */ if (ca->epoch_start && delta > 0) { ca->epoch_start += delta; if (after(ca->epoch_start, now)) ca->epoch_start = now; } return; } } /* calculate the cubic root of x using a table lookup followed by one * Newton-Raphson iteration. * Avg err ~= 0.195% */ static u32 cubic_root(u64 a) { u32 x, b, shift; /* * cbrt(x) MSB values for x MSB values in [0..63]. * Precomputed then refined by hand - Willy Tarreau * * For x in [0..63], * v = cbrt(x << 18) - 1 * cbrt(x) = (v[x] + 10) >> 6 */ static const u8 v[] = { /* 0x00 */ 0, 54, 54, 54, 118, 118, 118, 118, /* 0x08 */ 123, 129, 134, 138, 143, 147, 151, 156, /* 0x10 */ 157, 161, 164, 168, 170, 173, 176, 179, /* 0x18 */ 181, 185, 187, 190, 192, 194, 197, 199, /* 0x20 */ 200, 202, 204, 206, 209, 211, 213, 215, /* 0x28 */ 217, 219, 221, 222, 224, 225, 227, 229, /* 0x30 */ 231, 232, 234, 236, 237, 239, 240, 242, /* 0x38 */ 244, 245, 246, 248, 250, 251, 252, 254, }; b = fls64(a); if (b < 7) { /* a in [0..63] */ return ((u32)v[(u32)a] + 35) >> 6; } b = ((b * 84) >> 8) - 1; shift = (a >> (b * 3)); x = ((u32)(((u32)v[shift] + 10) << b)) >> 6; /* * Newton-Raphson iteration * 2 * x = ( 2 * x + a / x ) / 3 * k+1 k k */ x = (2 * x + (u32)div64_u64(a, (u64)x * (u64)(x - 1))); x = ((x * 341) >> 10); return x; } /* * Compute congestion window to use. */ static inline void bictcp_update(struct bictcp *ca, u32 cwnd, u32 acked) { u32 delta, bic_target, max_cnt; u64 offs, t; ca->ack_cnt += acked; /* count the number of ACKed packets */ if (ca->last_cwnd == cwnd && (s32)(tcp_jiffies32 - ca->last_time) <= HZ / 32) return; /* The CUBIC function can update ca->cnt at most once per jiffy. * On all cwnd reduction events, ca->epoch_start is set to 0, * which will force a recalculation of ca->cnt. */ if (ca->epoch_start && tcp_jiffies32 == ca->last_time) goto tcp_friendliness; ca->last_cwnd = cwnd; ca->last_time = tcp_jiffies32; if (ca->epoch_start == 0) { ca->epoch_start = tcp_jiffies32; /* record beginning */ ca->ack_cnt = acked; /* start counting */ ca->tcp_cwnd = cwnd; /* syn with cubic */ if (ca->last_max_cwnd <= cwnd) { ca->bic_K = 0; ca->bic_origin_point = cwnd; } else { /* Compute new K based on * (wmax-cwnd) * (srtt>>3 / HZ) / c * 2^(3*bictcp_HZ) */ ca->bic_K = cubic_root(cube_factor * (ca->last_max_cwnd - cwnd)); ca->bic_origin_point = ca->last_max_cwnd; } } /* cubic function - calc*/ /* calculate c * time^3 / rtt, * while considering overflow in calculation of time^3 * (so time^3 is done by using 64 bit) * and without the support of division of 64bit numbers * (so all divisions are done by using 32 bit) * also NOTE the unit of those veriables * time = (t - K) / 2^bictcp_HZ * c = bic_scale >> 10 * rtt = (srtt >> 3) / HZ * !!! The following code does not have overflow problems, * if the cwnd < 1 million packets !!! */ t = (s32)(tcp_jiffies32 - ca->epoch_start); t += usecs_to_jiffies(ca->delay_min); /* change the unit from HZ to bictcp_HZ */ t <<= BICTCP_HZ; do_div(t, HZ); if (t < ca->bic_K) /* t - K */ offs = ca->bic_K - t; else offs = t - ca->bic_K; /* c/rtt * (t-K)^3 */ delta = (cube_rtt_scale * offs * offs * offs) >> (10+3*BICTCP_HZ); if (t < ca->bic_K) /* below origin*/ bic_target = ca->bic_origin_point - delta; else /* above origin*/ bic_target = ca->bic_origin_point + delta; /* cubic function - calc bictcp_cnt*/ if (bic_target > cwnd) { ca->cnt = cwnd / (bic_target - cwnd); } else { ca->cnt = 100 * cwnd; /* very small increment*/ } /* * The initial growth of cubic function may be too conservative * when the available bandwidth is still unknown. */ if (ca->last_max_cwnd == 0 && ca->cnt > 20) ca->cnt = 20; /* increase cwnd 5% per RTT */ tcp_friendliness: /* TCP Friendly */ if (tcp_friendliness) { u32 scale = beta_scale; delta = (cwnd * scale) >> 3; while (ca->ack_cnt > delta) { /* update tcp cwnd */ ca->ack_cnt -= delta; ca->tcp_cwnd++; } if (ca->tcp_cwnd > cwnd) { /* if bic is slower than tcp */ delta = ca->tcp_cwnd - cwnd; max_cnt = cwnd / delta; if (ca->cnt > max_cnt) ca->cnt = max_cnt; } } /* The maximum rate of cwnd increase CUBIC allows is 1 packet per * 2 packets ACKed, meaning cwnd grows at 1.5x per RTT. */ ca->cnt = max(ca->cnt, 2U); } __bpf_kfunc static void cubictcp_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); if (!tcp_is_cwnd_limited(sk)) return; if (tcp_in_slow_start(tp)) { acked = tcp_slow_start(tp, acked); if (!acked) return; } bictcp_update(ca, tcp_snd_cwnd(tp), acked); tcp_cong_avoid_ai(tp, ca->cnt, acked); } __bpf_kfunc static u32 cubictcp_recalc_ssthresh(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); ca->epoch_start = 0; /* end of epoch */ /* Wmax and fast convergence */ if (tcp_snd_cwnd(tp) < ca->last_max_cwnd && fast_convergence) ca->last_max_cwnd = (tcp_snd_cwnd(tp) * (BICTCP_BETA_SCALE + beta)) / (2 * BICTCP_BETA_SCALE); else ca->last_max_cwnd = tcp_snd_cwnd(tp); return max((tcp_snd_cwnd(tp) * beta) / BICTCP_BETA_SCALE, 2U); } __bpf_kfunc static void cubictcp_state(struct sock *sk, u8 new_state) { if (new_state == TCP_CA_Loss) { bictcp_reset(inet_csk_ca(sk)); bictcp_hystart_reset(sk); } } /* Account for TSO/GRO delays. * Otherwise short RTT flows could get too small ssthresh, since during * slow start we begin with small TSO packets and ca->delay_min would * not account for long aggregation delay when TSO packets get bigger. * Ideally even with a very small RTT we would like to have at least one * TSO packet being sent and received by GRO, and another one in qdisc layer. * We apply another 100% factor because @rate is doubled at this point. * We cap the cushion to 1ms. */ static u32 hystart_ack_delay(const struct sock *sk) { unsigned long rate; rate = READ_ONCE(sk->sk_pacing_rate); if (!rate) return 0; return min_t(u64, USEC_PER_MSEC, div64_ul((u64)sk->sk_gso_max_size * 4 * USEC_PER_SEC, rate)); } static void hystart_update(struct sock *sk, u32 delay) { struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); u32 threshold; if (after(tp->snd_una, ca->end_seq)) bictcp_hystart_reset(sk); if (hystart_detect & HYSTART_ACK_TRAIN) { u32 now = bictcp_clock_us(sk); /* first detection parameter - ack-train detection */ if ((s32)(now - ca->last_ack) <= hystart_ack_delta_us) { ca->last_ack = now; threshold = ca->delay_min + hystart_ack_delay(sk); /* Hystart ack train triggers if we get ack past * ca->delay_min/2. * Pacing might have delayed packets up to RTT/2 * during slow start. */ if (sk->sk_pacing_status == SK_PACING_NONE) threshold >>= 1; if ((s32)(now - ca->round_start) > threshold) { ca->found = 1; pr_debug("hystart_ack_train (%u > %u) delay_min %u (+ ack_delay %u) cwnd %u\n", now - ca->round_start, threshold, ca->delay_min, hystart_ack_delay(sk), tcp_snd_cwnd(tp)); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHYSTARTTRAINDETECT); NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPHYSTARTTRAINCWND, tcp_snd_cwnd(tp)); tp->snd_ssthresh = tcp_snd_cwnd(tp); } } } if (hystart_detect & HYSTART_DELAY) { /* obtain the minimum delay of more than sampling packets */ if (ca->curr_rtt > delay) ca->curr_rtt = delay; if (ca->sample_cnt < HYSTART_MIN_SAMPLES) { ca->sample_cnt++; } else { if (ca->curr_rtt > ca->delay_min + HYSTART_DELAY_THRESH(ca->delay_min >> 3)) { ca->found = 1; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHYSTARTDELAYDETECT); NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPHYSTARTDELAYCWND, tcp_snd_cwnd(tp)); tp->snd_ssthresh = tcp_snd_cwnd(tp); } } } } __bpf_kfunc static void cubictcp_acked(struct sock *sk, const struct ack_sample *sample) { const struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); u32 delay; /* Some calls are for duplicates without timetamps */ if (sample->rtt_us < 0) return; /* Discard delay samples right after fast recovery */ if (ca->epoch_start && (s32)(tcp_jiffies32 - ca->epoch_start) < HZ) return; delay = sample->rtt_us; if (delay == 0) delay = 1; /* first time call or link delay decreases */ if (ca->delay_min == 0 || ca->delay_min > delay) ca->delay_min = delay; /* hystart triggers when cwnd is larger than some threshold */ if (!ca->found && tcp_in_slow_start(tp) && hystart && tcp_snd_cwnd(tp) >= hystart_low_window) hystart_update(sk, delay); } static struct tcp_congestion_ops cubictcp __read_mostly = { .init = cubictcp_init, .ssthresh = cubictcp_recalc_ssthresh, .cong_avoid = cubictcp_cong_avoid, .set_state = cubictcp_state, .undo_cwnd = tcp_reno_undo_cwnd, .cwnd_event = cubictcp_cwnd_event, .pkts_acked = cubictcp_acked, .owner = THIS_MODULE, .name = "cubic", }; BTF_SET8_START(tcp_cubic_check_kfunc_ids) #ifdef CONFIG_X86 #ifdef CONFIG_DYNAMIC_FTRACE BTF_ID_FLAGS(func, cubictcp_init) BTF_ID_FLAGS(func, cubictcp_recalc_ssthresh) BTF_ID_FLAGS(func, cubictcp_cong_avoid) BTF_ID_FLAGS(func, cubictcp_state) BTF_ID_FLAGS(func, cubictcp_cwnd_event) BTF_ID_FLAGS(func, cubictcp_acked) #endif #endif BTF_SET8_END(tcp_cubic_check_kfunc_ids) static const struct btf_kfunc_id_set tcp_cubic_kfunc_set = { .owner = THIS_MODULE, .set = &tcp_cubic_check_kfunc_ids, }; static int __init cubictcp_register(void) { int ret; BUILD_BUG_ON(sizeof(struct bictcp) > ICSK_CA_PRIV_SIZE); /* Precompute a bunch of the scaling factors that are used per-packet * based on SRTT of 100ms */ beta_scale = 8*(BICTCP_BETA_SCALE+beta) / 3 / (BICTCP_BETA_SCALE - beta); cube_rtt_scale = (bic_scale * 10); /* 1024*c/rtt */ /* calculate the "K" for (wmax-cwnd) = c/rtt * K^3 * so K = cubic_root( (wmax-cwnd)*rtt/c ) * the unit of K is bictcp_HZ=2^10, not HZ * * c = bic_scale >> 10 * rtt = 100ms * * the following code has been designed and tested for * cwnd < 1 million packets * RTT < 100 seconds * HZ < 1,000,00 (corresponding to 10 nano-second) */ /* 1/c * 2^2*bictcp_HZ * srtt */ cube_factor = 1ull << (10+3*BICTCP_HZ); /* 2^40 */ /* divide by bic_scale and by constant Srtt (100ms) */ do_div(cube_factor, bic_scale * 10); ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS, &tcp_cubic_kfunc_set); if (ret < 0) return ret; return tcp_register_congestion_control(&cubictcp); } static void __exit cubictcp_unregister(void) { tcp_unregister_congestion_control(&cubictcp); } module_init(cubictcp_register); module_exit(cubictcp_unregister); MODULE_AUTHOR("Sangtae Ha, Stephen Hemminger"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("CUBIC TCP"); MODULE_VERSION("2.3");
linux-master
net/ipv4/tcp_cubic.c
// SPDX-License-Identifier: GPL-2.0-only #include <linux/netlink.h> #include <linux/nospec.h> #include <linux/rtnetlink.h> #include <linux/types.h> #include <net/ip.h> #include <net/net_namespace.h> #include <net/tcp.h> static int ip_metrics_convert(struct net *net, struct nlattr *fc_mx, int fc_mx_len, u32 *metrics, struct netlink_ext_ack *extack) { bool ecn_ca = false; struct nlattr *nla; int remaining; nla_for_each_attr(nla, fc_mx, fc_mx_len, remaining) { int type = nla_type(nla); u32 val; if (!type) continue; if (type > RTAX_MAX) { NL_SET_ERR_MSG(extack, "Invalid metric type"); return -EINVAL; } type = array_index_nospec(type, RTAX_MAX + 1); if (type == RTAX_CC_ALGO) { char tmp[TCP_CA_NAME_MAX]; nla_strscpy(tmp, nla, sizeof(tmp)); val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca); if (val == TCP_CA_UNSPEC) { NL_SET_ERR_MSG(extack, "Unknown tcp congestion algorithm"); return -EINVAL; } } else { if (nla_len(nla) != sizeof(u32)) { NL_SET_ERR_MSG_ATTR(extack, nla, "Invalid attribute in metrics"); return -EINVAL; } val = nla_get_u32(nla); } if (type == RTAX_ADVMSS && val > 65535 - 40) val = 65535 - 40; if (type == RTAX_MTU && val > 65535 - 15) val = 65535 - 15; if (type == RTAX_HOPLIMIT && val > 255) val = 255; if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK)) { NL_SET_ERR_MSG(extack, "Unknown flag set in feature mask in metrics attribute"); return -EINVAL; } metrics[type - 1] = val; } if (ecn_ca) metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA; return 0; } struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx, int fc_mx_len, struct netlink_ext_ack *extack) { struct dst_metrics *fib_metrics; int err; if (!fc_mx) return (struct dst_metrics *)&dst_default_metrics; fib_metrics = kzalloc(sizeof(*fib_metrics), GFP_KERNEL); if (unlikely(!fib_metrics)) return ERR_PTR(-ENOMEM); err = ip_metrics_convert(net, fc_mx, fc_mx_len, fib_metrics->metrics, extack); if (!err) { refcount_set(&fib_metrics->refcnt, 1); } else { kfree(fib_metrics); fib_metrics = ERR_PTR(err); } return fib_metrics; } EXPORT_SYMBOL_GPL(ip_fib_metrics_init);
linux-master
net/ipv4/metrics.c
// SPDX-License-Identifier: GPL-2.0 /* Generic nexthop implementation * * Copyright (c) 2017-19 Cumulus Networks * Copyright (c) 2017-19 David Ahern <[email protected]> */ #include <linux/nexthop.h> #include <linux/rtnetlink.h> #include <linux/slab.h> #include <linux/vmalloc.h> #include <net/arp.h> #include <net/ipv6_stubs.h> #include <net/lwtunnel.h> #include <net/ndisc.h> #include <net/nexthop.h> #include <net/route.h> #include <net/sock.h> #define NH_RES_DEFAULT_IDLE_TIMER (120 * HZ) #define NH_RES_DEFAULT_UNBALANCED_TIMER 0 /* No forced rebalancing. */ static void remove_nexthop(struct net *net, struct nexthop *nh, struct nl_info *nlinfo); #define NH_DEV_HASHBITS 8 #define NH_DEV_HASHSIZE (1U << NH_DEV_HASHBITS) static const struct nla_policy rtm_nh_policy_new[] = { [NHA_ID] = { .type = NLA_U32 }, [NHA_GROUP] = { .type = NLA_BINARY }, [NHA_GROUP_TYPE] = { .type = NLA_U16 }, [NHA_BLACKHOLE] = { .type = NLA_FLAG }, [NHA_OIF] = { .type = NLA_U32 }, [NHA_GATEWAY] = { .type = NLA_BINARY }, [NHA_ENCAP_TYPE] = { .type = NLA_U16 }, [NHA_ENCAP] = { .type = NLA_NESTED }, [NHA_FDB] = { .type = NLA_FLAG }, [NHA_RES_GROUP] = { .type = NLA_NESTED }, }; static const struct nla_policy rtm_nh_policy_get[] = { [NHA_ID] = { .type = NLA_U32 }, }; static const struct nla_policy rtm_nh_policy_dump[] = { [NHA_OIF] = { .type = NLA_U32 }, [NHA_GROUPS] = { .type = NLA_FLAG }, [NHA_MASTER] = { .type = NLA_U32 }, [NHA_FDB] = { .type = NLA_FLAG }, }; static const struct nla_policy rtm_nh_res_policy_new[] = { [NHA_RES_GROUP_BUCKETS] = { .type = NLA_U16 }, [NHA_RES_GROUP_IDLE_TIMER] = { .type = NLA_U32 }, [NHA_RES_GROUP_UNBALANCED_TIMER] = { .type = NLA_U32 }, }; static const struct nla_policy rtm_nh_policy_dump_bucket[] = { [NHA_ID] = { .type = NLA_U32 }, [NHA_OIF] = { .type = NLA_U32 }, [NHA_MASTER] = { .type = NLA_U32 }, [NHA_RES_BUCKET] = { .type = NLA_NESTED }, }; static const struct nla_policy rtm_nh_res_bucket_policy_dump[] = { [NHA_RES_BUCKET_NH_ID] = { .type = NLA_U32 }, }; static const struct nla_policy rtm_nh_policy_get_bucket[] = { [NHA_ID] = { .type = NLA_U32 }, [NHA_RES_BUCKET] = { .type = NLA_NESTED }, }; static const struct nla_policy rtm_nh_res_bucket_policy_get[] = { [NHA_RES_BUCKET_INDEX] = { .type = NLA_U16 }, }; static bool nexthop_notifiers_is_empty(struct net *net) { return !net->nexthop.notifier_chain.head; } static void __nh_notifier_single_info_init(struct nh_notifier_single_info *nh_info, const struct nh_info *nhi) { nh_info->dev = nhi->fib_nhc.nhc_dev; nh_info->gw_family = nhi->fib_nhc.nhc_gw_family; if (nh_info->gw_family == AF_INET) nh_info->ipv4 = nhi->fib_nhc.nhc_gw.ipv4; else if (nh_info->gw_family == AF_INET6) nh_info->ipv6 = nhi->fib_nhc.nhc_gw.ipv6; nh_info->is_reject = nhi->reject_nh; nh_info->is_fdb = nhi->fdb_nh; nh_info->has_encap = !!nhi->fib_nhc.nhc_lwtstate; } static int nh_notifier_single_info_init(struct nh_notifier_info *info, const struct nexthop *nh) { struct nh_info *nhi = rtnl_dereference(nh->nh_info); info->type = NH_NOTIFIER_INFO_TYPE_SINGLE; info->nh = kzalloc(sizeof(*info->nh), GFP_KERNEL); if (!info->nh) return -ENOMEM; __nh_notifier_single_info_init(info->nh, nhi); return 0; } static void nh_notifier_single_info_fini(struct nh_notifier_info *info) { kfree(info->nh); } static int nh_notifier_mpath_info_init(struct nh_notifier_info *info, struct nh_group *nhg) { u16 num_nh = nhg->num_nh; int i; info->type = NH_NOTIFIER_INFO_TYPE_GRP; info->nh_grp = kzalloc(struct_size(info->nh_grp, nh_entries, num_nh), GFP_KERNEL); if (!info->nh_grp) return -ENOMEM; info->nh_grp->num_nh = num_nh; info->nh_grp->is_fdb = nhg->fdb_nh; for (i = 0; i < num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; struct nh_info *nhi; nhi = rtnl_dereference(nhge->nh->nh_info); info->nh_grp->nh_entries[i].id = nhge->nh->id; info->nh_grp->nh_entries[i].weight = nhge->weight; __nh_notifier_single_info_init(&info->nh_grp->nh_entries[i].nh, nhi); } return 0; } static int nh_notifier_res_table_info_init(struct nh_notifier_info *info, struct nh_group *nhg) { struct nh_res_table *res_table = rtnl_dereference(nhg->res_table); u16 num_nh_buckets = res_table->num_nh_buckets; unsigned long size; u16 i; info->type = NH_NOTIFIER_INFO_TYPE_RES_TABLE; size = struct_size(info->nh_res_table, nhs, num_nh_buckets); info->nh_res_table = __vmalloc(size, GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN); if (!info->nh_res_table) return -ENOMEM; info->nh_res_table->num_nh_buckets = num_nh_buckets; for (i = 0; i < num_nh_buckets; i++) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; struct nh_grp_entry *nhge; struct nh_info *nhi; nhge = rtnl_dereference(bucket->nh_entry); nhi = rtnl_dereference(nhge->nh->nh_info); __nh_notifier_single_info_init(&info->nh_res_table->nhs[i], nhi); } return 0; } static int nh_notifier_grp_info_init(struct nh_notifier_info *info, const struct nexthop *nh) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); if (nhg->hash_threshold) return nh_notifier_mpath_info_init(info, nhg); else if (nhg->resilient) return nh_notifier_res_table_info_init(info, nhg); return -EINVAL; } static void nh_notifier_grp_info_fini(struct nh_notifier_info *info, const struct nexthop *nh) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); if (nhg->hash_threshold) kfree(info->nh_grp); else if (nhg->resilient) vfree(info->nh_res_table); } static int nh_notifier_info_init(struct nh_notifier_info *info, const struct nexthop *nh) { info->id = nh->id; if (nh->is_group) return nh_notifier_grp_info_init(info, nh); else return nh_notifier_single_info_init(info, nh); } static void nh_notifier_info_fini(struct nh_notifier_info *info, const struct nexthop *nh) { if (nh->is_group) nh_notifier_grp_info_fini(info, nh); else nh_notifier_single_info_fini(info); } static int call_nexthop_notifiers(struct net *net, enum nexthop_event_type event_type, struct nexthop *nh, struct netlink_ext_ack *extack) { struct nh_notifier_info info = { .net = net, .extack = extack, }; int err; ASSERT_RTNL(); if (nexthop_notifiers_is_empty(net)) return 0; err = nh_notifier_info_init(&info, nh); if (err) { NL_SET_ERR_MSG(extack, "Failed to initialize nexthop notifier info"); return err; } err = blocking_notifier_call_chain(&net->nexthop.notifier_chain, event_type, &info); nh_notifier_info_fini(&info, nh); return notifier_to_errno(err); } static int nh_notifier_res_bucket_idle_timer_get(const struct nh_notifier_info *info, bool force, unsigned int *p_idle_timer_ms) { struct nh_res_table *res_table; struct nh_group *nhg; struct nexthop *nh; int err = 0; /* When 'force' is false, nexthop bucket replacement is performed * because the bucket was deemed to be idle. In this case, capable * listeners can choose to perform an atomic replacement: The bucket is * only replaced if it is inactive. However, if the idle timer interval * is smaller than the interval in which a listener is querying * buckets' activity from the device, then atomic replacement should * not be tried. Pass the idle timer value to listeners, so that they * could determine which type of replacement to perform. */ if (force) { *p_idle_timer_ms = 0; return 0; } rcu_read_lock(); nh = nexthop_find_by_id(info->net, info->id); if (!nh) { err = -EINVAL; goto out; } nhg = rcu_dereference(nh->nh_grp); res_table = rcu_dereference(nhg->res_table); *p_idle_timer_ms = jiffies_to_msecs(res_table->idle_timer); out: rcu_read_unlock(); return err; } static int nh_notifier_res_bucket_info_init(struct nh_notifier_info *info, u16 bucket_index, bool force, struct nh_info *oldi, struct nh_info *newi) { unsigned int idle_timer_ms; int err; err = nh_notifier_res_bucket_idle_timer_get(info, force, &idle_timer_ms); if (err) return err; info->type = NH_NOTIFIER_INFO_TYPE_RES_BUCKET; info->nh_res_bucket = kzalloc(sizeof(*info->nh_res_bucket), GFP_KERNEL); if (!info->nh_res_bucket) return -ENOMEM; info->nh_res_bucket->bucket_index = bucket_index; info->nh_res_bucket->idle_timer_ms = idle_timer_ms; info->nh_res_bucket->force = force; __nh_notifier_single_info_init(&info->nh_res_bucket->old_nh, oldi); __nh_notifier_single_info_init(&info->nh_res_bucket->new_nh, newi); return 0; } static void nh_notifier_res_bucket_info_fini(struct nh_notifier_info *info) { kfree(info->nh_res_bucket); } static int __call_nexthop_res_bucket_notifiers(struct net *net, u32 nhg_id, u16 bucket_index, bool force, struct nh_info *oldi, struct nh_info *newi, struct netlink_ext_ack *extack) { struct nh_notifier_info info = { .net = net, .extack = extack, .id = nhg_id, }; int err; if (nexthop_notifiers_is_empty(net)) return 0; err = nh_notifier_res_bucket_info_init(&info, bucket_index, force, oldi, newi); if (err) return err; err = blocking_notifier_call_chain(&net->nexthop.notifier_chain, NEXTHOP_EVENT_BUCKET_REPLACE, &info); nh_notifier_res_bucket_info_fini(&info); return notifier_to_errno(err); } /* There are three users of RES_TABLE, and NHs etc. referenced from there: * * 1) a collection of callbacks for NH maintenance. This operates under * RTNL, * 2) the delayed work that gradually balances the resilient table, * 3) and nexthop_select_path(), operating under RCU. * * Both the delayed work and the RTNL block are writers, and need to * maintain mutual exclusion. Since there are only two and well-known * writers for each table, the RTNL code can make sure it has exclusive * access thus: * * - Have the DW operate without locking; * - synchronously cancel the DW; * - do the writing; * - if the write was not actually a delete, call upkeep, which schedules * DW again if necessary. * * The functions that are always called from the RTNL context use * rtnl_dereference(). The functions that can also be called from the DW do * a raw dereference and rely on the above mutual exclusion scheme. */ #define nh_res_dereference(p) (rcu_dereference_raw(p)) static int call_nexthop_res_bucket_notifiers(struct net *net, u32 nhg_id, u16 bucket_index, bool force, struct nexthop *old_nh, struct nexthop *new_nh, struct netlink_ext_ack *extack) { struct nh_info *oldi = nh_res_dereference(old_nh->nh_info); struct nh_info *newi = nh_res_dereference(new_nh->nh_info); return __call_nexthop_res_bucket_notifiers(net, nhg_id, bucket_index, force, oldi, newi, extack); } static int call_nexthop_res_table_notifiers(struct net *net, struct nexthop *nh, struct netlink_ext_ack *extack) { struct nh_notifier_info info = { .net = net, .extack = extack, }; struct nh_group *nhg; int err; ASSERT_RTNL(); if (nexthop_notifiers_is_empty(net)) return 0; /* At this point, the nexthop buckets are still not populated. Only * emit a notification with the logical nexthops, so that a listener * could potentially veto it in case of unsupported configuration. */ nhg = rtnl_dereference(nh->nh_grp); err = nh_notifier_mpath_info_init(&info, nhg); if (err) { NL_SET_ERR_MSG(extack, "Failed to initialize nexthop notifier info"); return err; } err = blocking_notifier_call_chain(&net->nexthop.notifier_chain, NEXTHOP_EVENT_RES_TABLE_PRE_REPLACE, &info); kfree(info.nh_grp); return notifier_to_errno(err); } static int call_nexthop_notifier(struct notifier_block *nb, struct net *net, enum nexthop_event_type event_type, struct nexthop *nh, struct netlink_ext_ack *extack) { struct nh_notifier_info info = { .net = net, .extack = extack, }; int err; err = nh_notifier_info_init(&info, nh); if (err) return err; err = nb->notifier_call(nb, event_type, &info); nh_notifier_info_fini(&info, nh); return notifier_to_errno(err); } static unsigned int nh_dev_hashfn(unsigned int val) { unsigned int mask = NH_DEV_HASHSIZE - 1; return (val ^ (val >> NH_DEV_HASHBITS) ^ (val >> (NH_DEV_HASHBITS * 2))) & mask; } static void nexthop_devhash_add(struct net *net, struct nh_info *nhi) { struct net_device *dev = nhi->fib_nhc.nhc_dev; struct hlist_head *head; unsigned int hash; WARN_ON(!dev); hash = nh_dev_hashfn(dev->ifindex); head = &net->nexthop.devhash[hash]; hlist_add_head(&nhi->dev_hash, head); } static void nexthop_free_group(struct nexthop *nh) { struct nh_group *nhg; int i; nhg = rcu_dereference_raw(nh->nh_grp); for (i = 0; i < nhg->num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; WARN_ON(!list_empty(&nhge->nh_list)); nexthop_put(nhge->nh); } WARN_ON(nhg->spare == nhg); if (nhg->resilient) vfree(rcu_dereference_raw(nhg->res_table)); kfree(nhg->spare); kfree(nhg); } static void nexthop_free_single(struct nexthop *nh) { struct nh_info *nhi; nhi = rcu_dereference_raw(nh->nh_info); switch (nhi->family) { case AF_INET: fib_nh_release(nh->net, &nhi->fib_nh); break; case AF_INET6: ipv6_stub->fib6_nh_release(&nhi->fib6_nh); break; } kfree(nhi); } void nexthop_free_rcu(struct rcu_head *head) { struct nexthop *nh = container_of(head, struct nexthop, rcu); if (nh->is_group) nexthop_free_group(nh); else nexthop_free_single(nh); kfree(nh); } EXPORT_SYMBOL_GPL(nexthop_free_rcu); static struct nexthop *nexthop_alloc(void) { struct nexthop *nh; nh = kzalloc(sizeof(struct nexthop), GFP_KERNEL); if (nh) { INIT_LIST_HEAD(&nh->fi_list); INIT_LIST_HEAD(&nh->f6i_list); INIT_LIST_HEAD(&nh->grp_list); INIT_LIST_HEAD(&nh->fdb_list); } return nh; } static struct nh_group *nexthop_grp_alloc(u16 num_nh) { struct nh_group *nhg; nhg = kzalloc(struct_size(nhg, nh_entries, num_nh), GFP_KERNEL); if (nhg) nhg->num_nh = num_nh; return nhg; } static void nh_res_table_upkeep_dw(struct work_struct *work); static struct nh_res_table * nexthop_res_table_alloc(struct net *net, u32 nhg_id, struct nh_config *cfg) { const u16 num_nh_buckets = cfg->nh_grp_res_num_buckets; struct nh_res_table *res_table; unsigned long size; size = struct_size(res_table, nh_buckets, num_nh_buckets); res_table = __vmalloc(size, GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN); if (!res_table) return NULL; res_table->net = net; res_table->nhg_id = nhg_id; INIT_DELAYED_WORK(&res_table->upkeep_dw, &nh_res_table_upkeep_dw); INIT_LIST_HEAD(&res_table->uw_nh_entries); res_table->idle_timer = cfg->nh_grp_res_idle_timer; res_table->unbalanced_timer = cfg->nh_grp_res_unbalanced_timer; res_table->num_nh_buckets = num_nh_buckets; return res_table; } static void nh_base_seq_inc(struct net *net) { while (++net->nexthop.seq == 0) ; } /* no reference taken; rcu lock or rtnl must be held */ struct nexthop *nexthop_find_by_id(struct net *net, u32 id) { struct rb_node **pp, *parent = NULL, *next; pp = &net->nexthop.rb_root.rb_node; while (1) { struct nexthop *nh; next = rcu_dereference_raw(*pp); if (!next) break; parent = next; nh = rb_entry(parent, struct nexthop, rb_node); if (id < nh->id) pp = &next->rb_left; else if (id > nh->id) pp = &next->rb_right; else return nh; } return NULL; } EXPORT_SYMBOL_GPL(nexthop_find_by_id); /* used for auto id allocation; called with rtnl held */ static u32 nh_find_unused_id(struct net *net) { u32 id_start = net->nexthop.last_id_allocated; while (1) { net->nexthop.last_id_allocated++; if (net->nexthop.last_id_allocated == id_start) break; if (!nexthop_find_by_id(net, net->nexthop.last_id_allocated)) return net->nexthop.last_id_allocated; } return 0; } static void nh_res_time_set_deadline(unsigned long next_time, unsigned long *deadline) { if (time_before(next_time, *deadline)) *deadline = next_time; } static clock_t nh_res_table_unbalanced_time(struct nh_res_table *res_table) { if (list_empty(&res_table->uw_nh_entries)) return 0; return jiffies_delta_to_clock_t(jiffies - res_table->unbalanced_since); } static int nla_put_nh_group_res(struct sk_buff *skb, struct nh_group *nhg) { struct nh_res_table *res_table = rtnl_dereference(nhg->res_table); struct nlattr *nest; nest = nla_nest_start(skb, NHA_RES_GROUP); if (!nest) return -EMSGSIZE; if (nla_put_u16(skb, NHA_RES_GROUP_BUCKETS, res_table->num_nh_buckets) || nla_put_u32(skb, NHA_RES_GROUP_IDLE_TIMER, jiffies_to_clock_t(res_table->idle_timer)) || nla_put_u32(skb, NHA_RES_GROUP_UNBALANCED_TIMER, jiffies_to_clock_t(res_table->unbalanced_timer)) || nla_put_u64_64bit(skb, NHA_RES_GROUP_UNBALANCED_TIME, nh_res_table_unbalanced_time(res_table), NHA_RES_GROUP_PAD)) goto nla_put_failure; nla_nest_end(skb, nest); return 0; nla_put_failure: nla_nest_cancel(skb, nest); return -EMSGSIZE; } static int nla_put_nh_group(struct sk_buff *skb, struct nh_group *nhg) { struct nexthop_grp *p; size_t len = nhg->num_nh * sizeof(*p); struct nlattr *nla; u16 group_type = 0; int i; if (nhg->hash_threshold) group_type = NEXTHOP_GRP_TYPE_MPATH; else if (nhg->resilient) group_type = NEXTHOP_GRP_TYPE_RES; if (nla_put_u16(skb, NHA_GROUP_TYPE, group_type)) goto nla_put_failure; nla = nla_reserve(skb, NHA_GROUP, len); if (!nla) goto nla_put_failure; p = nla_data(nla); for (i = 0; i < nhg->num_nh; ++i) { p->id = nhg->nh_entries[i].nh->id; p->weight = nhg->nh_entries[i].weight - 1; p += 1; } if (nhg->resilient && nla_put_nh_group_res(skb, nhg)) goto nla_put_failure; return 0; nla_put_failure: return -EMSGSIZE; } static int nh_fill_node(struct sk_buff *skb, struct nexthop *nh, int event, u32 portid, u32 seq, unsigned int nlflags) { struct fib6_nh *fib6_nh; struct fib_nh *fib_nh; struct nlmsghdr *nlh; struct nh_info *nhi; struct nhmsg *nhm; nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nhm), nlflags); if (!nlh) return -EMSGSIZE; nhm = nlmsg_data(nlh); nhm->nh_family = AF_UNSPEC; nhm->nh_flags = nh->nh_flags; nhm->nh_protocol = nh->protocol; nhm->nh_scope = 0; nhm->resvd = 0; if (nla_put_u32(skb, NHA_ID, nh->id)) goto nla_put_failure; if (nh->is_group) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); if (nhg->fdb_nh && nla_put_flag(skb, NHA_FDB)) goto nla_put_failure; if (nla_put_nh_group(skb, nhg)) goto nla_put_failure; goto out; } nhi = rtnl_dereference(nh->nh_info); nhm->nh_family = nhi->family; if (nhi->reject_nh) { if (nla_put_flag(skb, NHA_BLACKHOLE)) goto nla_put_failure; goto out; } else if (nhi->fdb_nh) { if (nla_put_flag(skb, NHA_FDB)) goto nla_put_failure; } else { const struct net_device *dev; dev = nhi->fib_nhc.nhc_dev; if (dev && nla_put_u32(skb, NHA_OIF, dev->ifindex)) goto nla_put_failure; } nhm->nh_scope = nhi->fib_nhc.nhc_scope; switch (nhi->family) { case AF_INET: fib_nh = &nhi->fib_nh; if (fib_nh->fib_nh_gw_family && nla_put_be32(skb, NHA_GATEWAY, fib_nh->fib_nh_gw4)) goto nla_put_failure; break; case AF_INET6: fib6_nh = &nhi->fib6_nh; if (fib6_nh->fib_nh_gw_family && nla_put_in6_addr(skb, NHA_GATEWAY, &fib6_nh->fib_nh_gw6)) goto nla_put_failure; break; } if (nhi->fib_nhc.nhc_lwtstate && lwtunnel_fill_encap(skb, nhi->fib_nhc.nhc_lwtstate, NHA_ENCAP, NHA_ENCAP_TYPE) < 0) goto nla_put_failure; out: nlmsg_end(skb, nlh); return 0; nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static size_t nh_nlmsg_size_grp_res(struct nh_group *nhg) { return nla_total_size(0) + /* NHA_RES_GROUP */ nla_total_size(2) + /* NHA_RES_GROUP_BUCKETS */ nla_total_size(4) + /* NHA_RES_GROUP_IDLE_TIMER */ nla_total_size(4) + /* NHA_RES_GROUP_UNBALANCED_TIMER */ nla_total_size_64bit(8);/* NHA_RES_GROUP_UNBALANCED_TIME */ } static size_t nh_nlmsg_size_grp(struct nexthop *nh) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); size_t sz = sizeof(struct nexthop_grp) * nhg->num_nh; size_t tot = nla_total_size(sz) + nla_total_size(2); /* NHA_GROUP_TYPE */ if (nhg->resilient) tot += nh_nlmsg_size_grp_res(nhg); return tot; } static size_t nh_nlmsg_size_single(struct nexthop *nh) { struct nh_info *nhi = rtnl_dereference(nh->nh_info); size_t sz; /* covers NHA_BLACKHOLE since NHA_OIF and BLACKHOLE * are mutually exclusive */ sz = nla_total_size(4); /* NHA_OIF */ switch (nhi->family) { case AF_INET: if (nhi->fib_nh.fib_nh_gw_family) sz += nla_total_size(4); /* NHA_GATEWAY */ break; case AF_INET6: /* NHA_GATEWAY */ if (nhi->fib6_nh.fib_nh_gw_family) sz += nla_total_size(sizeof(const struct in6_addr)); break; } if (nhi->fib_nhc.nhc_lwtstate) { sz += lwtunnel_get_encap_size(nhi->fib_nhc.nhc_lwtstate); sz += nla_total_size(2); /* NHA_ENCAP_TYPE */ } return sz; } static size_t nh_nlmsg_size(struct nexthop *nh) { size_t sz = NLMSG_ALIGN(sizeof(struct nhmsg)); sz += nla_total_size(4); /* NHA_ID */ if (nh->is_group) sz += nh_nlmsg_size_grp(nh); else sz += nh_nlmsg_size_single(nh); return sz; } static void nexthop_notify(int event, struct nexthop *nh, struct nl_info *info) { unsigned int nlflags = info->nlh ? info->nlh->nlmsg_flags : 0; u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0; struct sk_buff *skb; int err = -ENOBUFS; skb = nlmsg_new(nh_nlmsg_size(nh), gfp_any()); if (!skb) goto errout; err = nh_fill_node(skb, nh, event, info->portid, seq, nlflags); if (err < 0) { /* -EMSGSIZE implies BUG in nh_nlmsg_size() */ WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; } rtnl_notify(skb, info->nl_net, info->portid, RTNLGRP_NEXTHOP, info->nlh, gfp_any()); return; errout: if (err < 0) rtnl_set_sk_err(info->nl_net, RTNLGRP_NEXTHOP, err); } static unsigned long nh_res_bucket_used_time(const struct nh_res_bucket *bucket) { return (unsigned long)atomic_long_read(&bucket->used_time); } static unsigned long nh_res_bucket_idle_point(const struct nh_res_table *res_table, const struct nh_res_bucket *bucket, unsigned long now) { unsigned long time = nh_res_bucket_used_time(bucket); /* Bucket was not used since it was migrated. The idle time is now. */ if (time == bucket->migrated_time) return now; return time + res_table->idle_timer; } static unsigned long nh_res_table_unb_point(const struct nh_res_table *res_table) { return res_table->unbalanced_since + res_table->unbalanced_timer; } static void nh_res_bucket_set_idle(const struct nh_res_table *res_table, struct nh_res_bucket *bucket) { unsigned long now = jiffies; atomic_long_set(&bucket->used_time, (long)now); bucket->migrated_time = now; } static void nh_res_bucket_set_busy(struct nh_res_bucket *bucket) { atomic_long_set(&bucket->used_time, (long)jiffies); } static clock_t nh_res_bucket_idle_time(const struct nh_res_bucket *bucket) { unsigned long used_time = nh_res_bucket_used_time(bucket); return jiffies_delta_to_clock_t(jiffies - used_time); } static int nh_fill_res_bucket(struct sk_buff *skb, struct nexthop *nh, struct nh_res_bucket *bucket, u16 bucket_index, int event, u32 portid, u32 seq, unsigned int nlflags, struct netlink_ext_ack *extack) { struct nh_grp_entry *nhge = nh_res_dereference(bucket->nh_entry); struct nlmsghdr *nlh; struct nlattr *nest; struct nhmsg *nhm; nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nhm), nlflags); if (!nlh) return -EMSGSIZE; nhm = nlmsg_data(nlh); nhm->nh_family = AF_UNSPEC; nhm->nh_flags = bucket->nh_flags; nhm->nh_protocol = nh->protocol; nhm->nh_scope = 0; nhm->resvd = 0; if (nla_put_u32(skb, NHA_ID, nh->id)) goto nla_put_failure; nest = nla_nest_start(skb, NHA_RES_BUCKET); if (!nest) goto nla_put_failure; if (nla_put_u16(skb, NHA_RES_BUCKET_INDEX, bucket_index) || nla_put_u32(skb, NHA_RES_BUCKET_NH_ID, nhge->nh->id) || nla_put_u64_64bit(skb, NHA_RES_BUCKET_IDLE_TIME, nh_res_bucket_idle_time(bucket), NHA_RES_BUCKET_PAD)) goto nla_put_failure_nest; nla_nest_end(skb, nest); nlmsg_end(skb, nlh); return 0; nla_put_failure_nest: nla_nest_cancel(skb, nest); nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static void nexthop_bucket_notify(struct nh_res_table *res_table, u16 bucket_index) { struct nh_res_bucket *bucket = &res_table->nh_buckets[bucket_index]; struct nh_grp_entry *nhge = nh_res_dereference(bucket->nh_entry); struct nexthop *nh = nhge->nh_parent; struct sk_buff *skb; int err = -ENOBUFS; skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) goto errout; err = nh_fill_res_bucket(skb, nh, bucket, bucket_index, RTM_NEWNEXTHOPBUCKET, 0, 0, NLM_F_REPLACE, NULL); if (err < 0) { kfree_skb(skb); goto errout; } rtnl_notify(skb, nh->net, 0, RTNLGRP_NEXTHOP, NULL, GFP_KERNEL); return; errout: if (err < 0) rtnl_set_sk_err(nh->net, RTNLGRP_NEXTHOP, err); } static bool valid_group_nh(struct nexthop *nh, unsigned int npaths, bool *is_fdb, struct netlink_ext_ack *extack) { if (nh->is_group) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); /* Nesting groups within groups is not supported. */ if (nhg->hash_threshold) { NL_SET_ERR_MSG(extack, "Hash-threshold group can not be a nexthop within a group"); return false; } if (nhg->resilient) { NL_SET_ERR_MSG(extack, "Resilient group can not be a nexthop within a group"); return false; } *is_fdb = nhg->fdb_nh; } else { struct nh_info *nhi = rtnl_dereference(nh->nh_info); if (nhi->reject_nh && npaths > 1) { NL_SET_ERR_MSG(extack, "Blackhole nexthop can not be used in a group with more than 1 path"); return false; } *is_fdb = nhi->fdb_nh; } return true; } static int nh_check_attr_fdb_group(struct nexthop *nh, u8 *nh_family, struct netlink_ext_ack *extack) { struct nh_info *nhi; nhi = rtnl_dereference(nh->nh_info); if (!nhi->fdb_nh) { NL_SET_ERR_MSG(extack, "FDB nexthop group can only have fdb nexthops"); return -EINVAL; } if (*nh_family == AF_UNSPEC) { *nh_family = nhi->family; } else if (*nh_family != nhi->family) { NL_SET_ERR_MSG(extack, "FDB nexthop group cannot have mixed family nexthops"); return -EINVAL; } return 0; } static int nh_check_attr_group(struct net *net, struct nlattr *tb[], size_t tb_size, u16 nh_grp_type, struct netlink_ext_ack *extack) { unsigned int len = nla_len(tb[NHA_GROUP]); u8 nh_family = AF_UNSPEC; struct nexthop_grp *nhg; unsigned int i, j; u8 nhg_fdb = 0; if (!len || len & (sizeof(struct nexthop_grp) - 1)) { NL_SET_ERR_MSG(extack, "Invalid length for nexthop group attribute"); return -EINVAL; } /* convert len to number of nexthop ids */ len /= sizeof(*nhg); nhg = nla_data(tb[NHA_GROUP]); for (i = 0; i < len; ++i) { if (nhg[i].resvd1 || nhg[i].resvd2) { NL_SET_ERR_MSG(extack, "Reserved fields in nexthop_grp must be 0"); return -EINVAL; } if (nhg[i].weight > 254) { NL_SET_ERR_MSG(extack, "Invalid value for weight"); return -EINVAL; } for (j = i + 1; j < len; ++j) { if (nhg[i].id == nhg[j].id) { NL_SET_ERR_MSG(extack, "Nexthop id can not be used twice in a group"); return -EINVAL; } } } if (tb[NHA_FDB]) nhg_fdb = 1; nhg = nla_data(tb[NHA_GROUP]); for (i = 0; i < len; ++i) { struct nexthop *nh; bool is_fdb_nh; nh = nexthop_find_by_id(net, nhg[i].id); if (!nh) { NL_SET_ERR_MSG(extack, "Invalid nexthop id"); return -EINVAL; } if (!valid_group_nh(nh, len, &is_fdb_nh, extack)) return -EINVAL; if (nhg_fdb && nh_check_attr_fdb_group(nh, &nh_family, extack)) return -EINVAL; if (!nhg_fdb && is_fdb_nh) { NL_SET_ERR_MSG(extack, "Non FDB nexthop group cannot have fdb nexthops"); return -EINVAL; } } for (i = NHA_GROUP_TYPE + 1; i < tb_size; ++i) { if (!tb[i]) continue; switch (i) { case NHA_FDB: continue; case NHA_RES_GROUP: if (nh_grp_type == NEXTHOP_GRP_TYPE_RES) continue; break; } NL_SET_ERR_MSG(extack, "No other attributes can be set in nexthop groups"); return -EINVAL; } return 0; } static bool ipv6_good_nh(const struct fib6_nh *nh) { int state = NUD_REACHABLE; struct neighbour *n; rcu_read_lock(); n = __ipv6_neigh_lookup_noref_stub(nh->fib_nh_dev, &nh->fib_nh_gw6); if (n) state = READ_ONCE(n->nud_state); rcu_read_unlock(); return !!(state & NUD_VALID); } static bool ipv4_good_nh(const struct fib_nh *nh) { int state = NUD_REACHABLE; struct neighbour *n; rcu_read_lock(); n = __ipv4_neigh_lookup_noref(nh->fib_nh_dev, (__force u32)nh->fib_nh_gw4); if (n) state = READ_ONCE(n->nud_state); rcu_read_unlock(); return !!(state & NUD_VALID); } static bool nexthop_is_good_nh(const struct nexthop *nh) { struct nh_info *nhi = rcu_dereference(nh->nh_info); switch (nhi->family) { case AF_INET: return ipv4_good_nh(&nhi->fib_nh); case AF_INET6: return ipv6_good_nh(&nhi->fib6_nh); } return false; } static struct nexthop *nexthop_select_path_fdb(struct nh_group *nhg, int hash) { int i; for (i = 0; i < nhg->num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; if (hash > atomic_read(&nhge->hthr.upper_bound)) continue; return nhge->nh; } WARN_ON_ONCE(1); return NULL; } static struct nexthop *nexthop_select_path_hthr(struct nh_group *nhg, int hash) { struct nexthop *rc = NULL; int i; if (nhg->fdb_nh) return nexthop_select_path_fdb(nhg, hash); for (i = 0; i < nhg->num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; /* nexthops always check if it is good and does * not rely on a sysctl for this behavior */ if (!nexthop_is_good_nh(nhge->nh)) continue; if (!rc) rc = nhge->nh; if (hash > atomic_read(&nhge->hthr.upper_bound)) continue; return nhge->nh; } return rc ? : nhg->nh_entries[0].nh; } static struct nexthop *nexthop_select_path_res(struct nh_group *nhg, int hash) { struct nh_res_table *res_table = rcu_dereference(nhg->res_table); u16 bucket_index = hash % res_table->num_nh_buckets; struct nh_res_bucket *bucket; struct nh_grp_entry *nhge; /* nexthop_select_path() is expected to return a non-NULL value, so * skip protocol validation and just hand out whatever there is. */ bucket = &res_table->nh_buckets[bucket_index]; nh_res_bucket_set_busy(bucket); nhge = rcu_dereference(bucket->nh_entry); return nhge->nh; } struct nexthop *nexthop_select_path(struct nexthop *nh, int hash) { struct nh_group *nhg; if (!nh->is_group) return nh; nhg = rcu_dereference(nh->nh_grp); if (nhg->hash_threshold) return nexthop_select_path_hthr(nhg, hash); else if (nhg->resilient) return nexthop_select_path_res(nhg, hash); /* Unreachable. */ return NULL; } EXPORT_SYMBOL_GPL(nexthop_select_path); int nexthop_for_each_fib6_nh(struct nexthop *nh, int (*cb)(struct fib6_nh *nh, void *arg), void *arg) { struct nh_info *nhi; int err; if (nh->is_group) { struct nh_group *nhg; int i; nhg = rcu_dereference_rtnl(nh->nh_grp); for (i = 0; i < nhg->num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; nhi = rcu_dereference_rtnl(nhge->nh->nh_info); err = cb(&nhi->fib6_nh, arg); if (err) return err; } } else { nhi = rcu_dereference_rtnl(nh->nh_info); err = cb(&nhi->fib6_nh, arg); if (err) return err; } return 0; } EXPORT_SYMBOL_GPL(nexthop_for_each_fib6_nh); static int check_src_addr(const struct in6_addr *saddr, struct netlink_ext_ack *extack) { if (!ipv6_addr_any(saddr)) { NL_SET_ERR_MSG(extack, "IPv6 routes using source address can not use nexthop objects"); return -EINVAL; } return 0; } int fib6_check_nexthop(struct nexthop *nh, struct fib6_config *cfg, struct netlink_ext_ack *extack) { struct nh_info *nhi; bool is_fdb_nh; /* fib6_src is unique to a fib6_info and limits the ability to cache * routes in fib6_nh within a nexthop that is potentially shared * across multiple fib entries. If the config wants to use source * routing it can not use nexthop objects. mlxsw also does not allow * fib6_src on routes. */ if (cfg && check_src_addr(&cfg->fc_src, extack) < 0) return -EINVAL; if (nh->is_group) { struct nh_group *nhg; nhg = rtnl_dereference(nh->nh_grp); if (nhg->has_v4) goto no_v4_nh; is_fdb_nh = nhg->fdb_nh; } else { nhi = rtnl_dereference(nh->nh_info); if (nhi->family == AF_INET) goto no_v4_nh; is_fdb_nh = nhi->fdb_nh; } if (is_fdb_nh) { NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop"); return -EINVAL; } return 0; no_v4_nh: NL_SET_ERR_MSG(extack, "IPv6 routes can not use an IPv4 nexthop"); return -EINVAL; } EXPORT_SYMBOL_GPL(fib6_check_nexthop); /* if existing nexthop has ipv6 routes linked to it, need * to verify this new spec works with ipv6 */ static int fib6_check_nh_list(struct nexthop *old, struct nexthop *new, struct netlink_ext_ack *extack) { struct fib6_info *f6i; if (list_empty(&old->f6i_list)) return 0; list_for_each_entry(f6i, &old->f6i_list, nh_list) { if (check_src_addr(&f6i->fib6_src.addr, extack) < 0) return -EINVAL; } return fib6_check_nexthop(new, NULL, extack); } static int nexthop_check_scope(struct nh_info *nhi, u8 scope, struct netlink_ext_ack *extack) { if (scope == RT_SCOPE_HOST && nhi->fib_nhc.nhc_gw_family) { NL_SET_ERR_MSG(extack, "Route with host scope can not have a gateway"); return -EINVAL; } if (nhi->fib_nhc.nhc_flags & RTNH_F_ONLINK && scope >= RT_SCOPE_LINK) { NL_SET_ERR_MSG(extack, "Scope mismatch with nexthop"); return -EINVAL; } return 0; } /* Invoked by fib add code to verify nexthop by id is ok with * config for prefix; parts of fib_check_nh not done when nexthop * object is used. */ int fib_check_nexthop(struct nexthop *nh, u8 scope, struct netlink_ext_ack *extack) { struct nh_info *nhi; int err = 0; if (nh->is_group) { struct nh_group *nhg; nhg = rtnl_dereference(nh->nh_grp); if (nhg->fdb_nh) { NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop"); err = -EINVAL; goto out; } if (scope == RT_SCOPE_HOST) { NL_SET_ERR_MSG(extack, "Route with host scope can not have multiple nexthops"); err = -EINVAL; goto out; } /* all nexthops in a group have the same scope */ nhi = rtnl_dereference(nhg->nh_entries[0].nh->nh_info); err = nexthop_check_scope(nhi, scope, extack); } else { nhi = rtnl_dereference(nh->nh_info); if (nhi->fdb_nh) { NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop"); err = -EINVAL; goto out; } err = nexthop_check_scope(nhi, scope, extack); } out: return err; } static int fib_check_nh_list(struct nexthop *old, struct nexthop *new, struct netlink_ext_ack *extack) { struct fib_info *fi; list_for_each_entry(fi, &old->fi_list, nh_list) { int err; err = fib_check_nexthop(new, fi->fib_scope, extack); if (err) return err; } return 0; } static bool nh_res_nhge_is_balanced(const struct nh_grp_entry *nhge) { return nhge->res.count_buckets == nhge->res.wants_buckets; } static bool nh_res_nhge_is_ow(const struct nh_grp_entry *nhge) { return nhge->res.count_buckets > nhge->res.wants_buckets; } static bool nh_res_nhge_is_uw(const struct nh_grp_entry *nhge) { return nhge->res.count_buckets < nhge->res.wants_buckets; } static bool nh_res_table_is_balanced(const struct nh_res_table *res_table) { return list_empty(&res_table->uw_nh_entries); } static void nh_res_bucket_unset_nh(struct nh_res_bucket *bucket) { struct nh_grp_entry *nhge; if (bucket->occupied) { nhge = nh_res_dereference(bucket->nh_entry); nhge->res.count_buckets--; bucket->occupied = false; } } static void nh_res_bucket_set_nh(struct nh_res_bucket *bucket, struct nh_grp_entry *nhge) { nh_res_bucket_unset_nh(bucket); bucket->occupied = true; rcu_assign_pointer(bucket->nh_entry, nhge); nhge->res.count_buckets++; } static bool nh_res_bucket_should_migrate(struct nh_res_table *res_table, struct nh_res_bucket *bucket, unsigned long *deadline, bool *force) { unsigned long now = jiffies; struct nh_grp_entry *nhge; unsigned long idle_point; if (!bucket->occupied) { /* The bucket is not occupied, its NHGE pointer is either * NULL or obsolete. We _have to_ migrate: set force. */ *force = true; return true; } nhge = nh_res_dereference(bucket->nh_entry); /* If the bucket is populated by an underweight or balanced * nexthop, do not migrate. */ if (!nh_res_nhge_is_ow(nhge)) return false; /* At this point we know that the bucket is populated with an * overweight nexthop. It needs to be migrated to a new nexthop if * the idle timer of unbalanced timer expired. */ idle_point = nh_res_bucket_idle_point(res_table, bucket, now); if (time_after_eq(now, idle_point)) { /* The bucket is idle. We _can_ migrate: unset force. */ *force = false; return true; } /* Unbalanced timer of 0 means "never force". */ if (res_table->unbalanced_timer) { unsigned long unb_point; unb_point = nh_res_table_unb_point(res_table); if (time_after(now, unb_point)) { /* The bucket is not idle, but the unbalanced timer * expired. We _can_ migrate, but set force anyway, * so that drivers know to ignore activity reports * from the HW. */ *force = true; return true; } nh_res_time_set_deadline(unb_point, deadline); } nh_res_time_set_deadline(idle_point, deadline); return false; } static bool nh_res_bucket_migrate(struct nh_res_table *res_table, u16 bucket_index, bool notify, bool notify_nl, bool force) { struct nh_res_bucket *bucket = &res_table->nh_buckets[bucket_index]; struct nh_grp_entry *new_nhge; struct netlink_ext_ack extack; int err; new_nhge = list_first_entry_or_null(&res_table->uw_nh_entries, struct nh_grp_entry, res.uw_nh_entry); if (WARN_ON_ONCE(!new_nhge)) /* If this function is called, "bucket" is either not * occupied, or it belongs to a next hop that is * overweight. In either case, there ought to be a * corresponding underweight next hop. */ return false; if (notify) { struct nh_grp_entry *old_nhge; old_nhge = nh_res_dereference(bucket->nh_entry); err = call_nexthop_res_bucket_notifiers(res_table->net, res_table->nhg_id, bucket_index, force, old_nhge->nh, new_nhge->nh, &extack); if (err) { pr_err_ratelimited("%s\n", extack._msg); if (!force) return false; /* It is not possible to veto a forced replacement, so * just clear the hardware flags from the nexthop * bucket to indicate to user space that this bucket is * not correctly populated in hardware. */ bucket->nh_flags &= ~(RTNH_F_OFFLOAD | RTNH_F_TRAP); } } nh_res_bucket_set_nh(bucket, new_nhge); nh_res_bucket_set_idle(res_table, bucket); if (notify_nl) nexthop_bucket_notify(res_table, bucket_index); if (nh_res_nhge_is_balanced(new_nhge)) list_del(&new_nhge->res.uw_nh_entry); return true; } #define NH_RES_UPKEEP_DW_MINIMUM_INTERVAL (HZ / 2) static void nh_res_table_upkeep(struct nh_res_table *res_table, bool notify, bool notify_nl) { unsigned long now = jiffies; unsigned long deadline; u16 i; /* Deadline is the next time that upkeep should be run. It is the * earliest time at which one of the buckets might be migrated. * Start at the most pessimistic estimate: either unbalanced_timer * from now, or if there is none, idle_timer from now. For each * encountered time point, call nh_res_time_set_deadline() to * refine the estimate. */ if (res_table->unbalanced_timer) deadline = now + res_table->unbalanced_timer; else deadline = now + res_table->idle_timer; for (i = 0; i < res_table->num_nh_buckets; i++) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; bool force; if (nh_res_bucket_should_migrate(res_table, bucket, &deadline, &force)) { if (!nh_res_bucket_migrate(res_table, i, notify, notify_nl, force)) { unsigned long idle_point; /* A driver can override the migration * decision if the HW reports that the * bucket is actually not idle. Therefore * remark the bucket as busy again and * update the deadline. */ nh_res_bucket_set_busy(bucket); idle_point = nh_res_bucket_idle_point(res_table, bucket, now); nh_res_time_set_deadline(idle_point, &deadline); } } } /* If the group is still unbalanced, schedule the next upkeep to * either the deadline computed above, or the minimum deadline, * whichever comes later. */ if (!nh_res_table_is_balanced(res_table)) { unsigned long now = jiffies; unsigned long min_deadline; min_deadline = now + NH_RES_UPKEEP_DW_MINIMUM_INTERVAL; if (time_before(deadline, min_deadline)) deadline = min_deadline; queue_delayed_work(system_power_efficient_wq, &res_table->upkeep_dw, deadline - now); } } static void nh_res_table_upkeep_dw(struct work_struct *work) { struct delayed_work *dw = to_delayed_work(work); struct nh_res_table *res_table; res_table = container_of(dw, struct nh_res_table, upkeep_dw); nh_res_table_upkeep(res_table, true, true); } static void nh_res_table_cancel_upkeep(struct nh_res_table *res_table) { cancel_delayed_work_sync(&res_table->upkeep_dw); } static void nh_res_group_rebalance(struct nh_group *nhg, struct nh_res_table *res_table) { int prev_upper_bound = 0; int total = 0; int w = 0; int i; INIT_LIST_HEAD(&res_table->uw_nh_entries); for (i = 0; i < nhg->num_nh; ++i) total += nhg->nh_entries[i].weight; for (i = 0; i < nhg->num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; int upper_bound; w += nhge->weight; upper_bound = DIV_ROUND_CLOSEST(res_table->num_nh_buckets * w, total); nhge->res.wants_buckets = upper_bound - prev_upper_bound; prev_upper_bound = upper_bound; if (nh_res_nhge_is_uw(nhge)) { if (list_empty(&res_table->uw_nh_entries)) res_table->unbalanced_since = jiffies; list_add(&nhge->res.uw_nh_entry, &res_table->uw_nh_entries); } } } /* Migrate buckets in res_table so that they reference NHGE's from NHG with * the right NH ID. Set those buckets that do not have a corresponding NHGE * entry in NHG as not occupied. */ static void nh_res_table_migrate_buckets(struct nh_res_table *res_table, struct nh_group *nhg) { u16 i; for (i = 0; i < res_table->num_nh_buckets; i++) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; u32 id = rtnl_dereference(bucket->nh_entry)->nh->id; bool found = false; int j; for (j = 0; j < nhg->num_nh; j++) { struct nh_grp_entry *nhge = &nhg->nh_entries[j]; if (nhge->nh->id == id) { nh_res_bucket_set_nh(bucket, nhge); found = true; break; } } if (!found) nh_res_bucket_unset_nh(bucket); } } static void replace_nexthop_grp_res(struct nh_group *oldg, struct nh_group *newg) { /* For NH group replacement, the new NHG might only have a stub * hash table with 0 buckets, because the number of buckets was not * specified. For NH removal, oldg and newg both reference the same * res_table. So in any case, in the following, we want to work * with oldg->res_table. */ struct nh_res_table *old_res_table = rtnl_dereference(oldg->res_table); unsigned long prev_unbalanced_since = old_res_table->unbalanced_since; bool prev_has_uw = !list_empty(&old_res_table->uw_nh_entries); nh_res_table_cancel_upkeep(old_res_table); nh_res_table_migrate_buckets(old_res_table, newg); nh_res_group_rebalance(newg, old_res_table); if (prev_has_uw && !list_empty(&old_res_table->uw_nh_entries)) old_res_table->unbalanced_since = prev_unbalanced_since; nh_res_table_upkeep(old_res_table, true, false); } static void nh_hthr_group_rebalance(struct nh_group *nhg) { int total = 0; int w = 0; int i; for (i = 0; i < nhg->num_nh; ++i) total += nhg->nh_entries[i].weight; for (i = 0; i < nhg->num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; int upper_bound; w += nhge->weight; upper_bound = DIV_ROUND_CLOSEST_ULL((u64)w << 31, total) - 1; atomic_set(&nhge->hthr.upper_bound, upper_bound); } } static void remove_nh_grp_entry(struct net *net, struct nh_grp_entry *nhge, struct nl_info *nlinfo) { struct nh_grp_entry *nhges, *new_nhges; struct nexthop *nhp = nhge->nh_parent; struct netlink_ext_ack extack; struct nexthop *nh = nhge->nh; struct nh_group *nhg, *newg; int i, j, err; WARN_ON(!nh); nhg = rtnl_dereference(nhp->nh_grp); newg = nhg->spare; /* last entry, keep it visible and remove the parent */ if (nhg->num_nh == 1) { remove_nexthop(net, nhp, nlinfo); return; } newg->has_v4 = false; newg->is_multipath = nhg->is_multipath; newg->hash_threshold = nhg->hash_threshold; newg->resilient = nhg->resilient; newg->fdb_nh = nhg->fdb_nh; newg->num_nh = nhg->num_nh; /* copy old entries to new except the one getting removed */ nhges = nhg->nh_entries; new_nhges = newg->nh_entries; for (i = 0, j = 0; i < nhg->num_nh; ++i) { struct nh_info *nhi; /* current nexthop getting removed */ if (nhg->nh_entries[i].nh == nh) { newg->num_nh--; continue; } nhi = rtnl_dereference(nhges[i].nh->nh_info); if (nhi->family == AF_INET) newg->has_v4 = true; list_del(&nhges[i].nh_list); new_nhges[j].nh_parent = nhges[i].nh_parent; new_nhges[j].nh = nhges[i].nh; new_nhges[j].weight = nhges[i].weight; list_add(&new_nhges[j].nh_list, &new_nhges[j].nh->grp_list); j++; } if (newg->hash_threshold) nh_hthr_group_rebalance(newg); else if (newg->resilient) replace_nexthop_grp_res(nhg, newg); rcu_assign_pointer(nhp->nh_grp, newg); list_del(&nhge->nh_list); nexthop_put(nhge->nh); /* Removal of a NH from a resilient group is notified through * bucket notifications. */ if (newg->hash_threshold) { err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, nhp, &extack); if (err) pr_err("%s\n", extack._msg); } if (nlinfo) nexthop_notify(RTM_NEWNEXTHOP, nhp, nlinfo); } static void remove_nexthop_from_groups(struct net *net, struct nexthop *nh, struct nl_info *nlinfo) { struct nh_grp_entry *nhge, *tmp; list_for_each_entry_safe(nhge, tmp, &nh->grp_list, nh_list) remove_nh_grp_entry(net, nhge, nlinfo); /* make sure all see the newly published array before releasing rtnl */ synchronize_net(); } static void remove_nexthop_group(struct nexthop *nh, struct nl_info *nlinfo) { struct nh_group *nhg = rcu_dereference_rtnl(nh->nh_grp); struct nh_res_table *res_table; int i, num_nh = nhg->num_nh; for (i = 0; i < num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; if (WARN_ON(!nhge->nh)) continue; list_del_init(&nhge->nh_list); } if (nhg->resilient) { res_table = rtnl_dereference(nhg->res_table); nh_res_table_cancel_upkeep(res_table); } } /* not called for nexthop replace */ static void __remove_nexthop_fib(struct net *net, struct nexthop *nh) { struct fib6_info *f6i, *tmp; bool do_flush = false; struct fib_info *fi; list_for_each_entry(fi, &nh->fi_list, nh_list) { fi->fib_flags |= RTNH_F_DEAD; do_flush = true; } if (do_flush) fib_flush(net); /* ip6_del_rt removes the entry from this list hence the _safe */ list_for_each_entry_safe(f6i, tmp, &nh->f6i_list, nh_list) { /* __ip6_del_rt does a release, so do a hold here */ fib6_info_hold(f6i); ipv6_stub->ip6_del_rt(net, f6i, !READ_ONCE(net->ipv4.sysctl_nexthop_compat_mode)); } } static void __remove_nexthop(struct net *net, struct nexthop *nh, struct nl_info *nlinfo) { __remove_nexthop_fib(net, nh); if (nh->is_group) { remove_nexthop_group(nh, nlinfo); } else { struct nh_info *nhi; nhi = rtnl_dereference(nh->nh_info); if (nhi->fib_nhc.nhc_dev) hlist_del(&nhi->dev_hash); remove_nexthop_from_groups(net, nh, nlinfo); } } static void remove_nexthop(struct net *net, struct nexthop *nh, struct nl_info *nlinfo) { call_nexthop_notifiers(net, NEXTHOP_EVENT_DEL, nh, NULL); /* remove from the tree */ rb_erase(&nh->rb_node, &net->nexthop.rb_root); if (nlinfo) nexthop_notify(RTM_DELNEXTHOP, nh, nlinfo); __remove_nexthop(net, nh, nlinfo); nh_base_seq_inc(net); nexthop_put(nh); } /* if any FIB entries reference this nexthop, any dst entries * need to be regenerated */ static void nh_rt_cache_flush(struct net *net, struct nexthop *nh, struct nexthop *replaced_nh) { struct fib6_info *f6i; struct nh_group *nhg; int i; if (!list_empty(&nh->fi_list)) rt_cache_flush(net); list_for_each_entry(f6i, &nh->f6i_list, nh_list) ipv6_stub->fib6_update_sernum(net, f6i); /* if an IPv6 group was replaced, we have to release all old * dsts to make sure all refcounts are released */ if (!replaced_nh->is_group) return; nhg = rtnl_dereference(replaced_nh->nh_grp); for (i = 0; i < nhg->num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; struct nh_info *nhi = rtnl_dereference(nhge->nh->nh_info); if (nhi->family == AF_INET6) ipv6_stub->fib6_nh_release_dsts(&nhi->fib6_nh); } } static int replace_nexthop_grp(struct net *net, struct nexthop *old, struct nexthop *new, const struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nh_res_table *tmp_table = NULL; struct nh_res_table *new_res_table; struct nh_res_table *old_res_table; struct nh_group *oldg, *newg; int i, err; if (!new->is_group) { NL_SET_ERR_MSG(extack, "Can not replace a nexthop group with a nexthop."); return -EINVAL; } oldg = rtnl_dereference(old->nh_grp); newg = rtnl_dereference(new->nh_grp); if (newg->hash_threshold != oldg->hash_threshold) { NL_SET_ERR_MSG(extack, "Can not replace a nexthop group with one of a different type."); return -EINVAL; } if (newg->hash_threshold) { err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new, extack); if (err) return err; } else if (newg->resilient) { new_res_table = rtnl_dereference(newg->res_table); old_res_table = rtnl_dereference(oldg->res_table); /* Accept if num_nh_buckets was not given, but if it was * given, demand that the value be correct. */ if (cfg->nh_grp_res_has_num_buckets && cfg->nh_grp_res_num_buckets != old_res_table->num_nh_buckets) { NL_SET_ERR_MSG(extack, "Can not change number of buckets of a resilient nexthop group."); return -EINVAL; } /* Emit a pre-replace notification so that listeners could veto * a potentially unsupported configuration. Otherwise, * individual bucket replacement notifications would need to be * vetoed, which is something that should only happen if the * bucket is currently active. */ err = call_nexthop_res_table_notifiers(net, new, extack); if (err) return err; if (cfg->nh_grp_res_has_idle_timer) old_res_table->idle_timer = cfg->nh_grp_res_idle_timer; if (cfg->nh_grp_res_has_unbalanced_timer) old_res_table->unbalanced_timer = cfg->nh_grp_res_unbalanced_timer; replace_nexthop_grp_res(oldg, newg); tmp_table = new_res_table; rcu_assign_pointer(newg->res_table, old_res_table); rcu_assign_pointer(newg->spare->res_table, old_res_table); } /* update parents - used by nexthop code for cleanup */ for (i = 0; i < newg->num_nh; i++) newg->nh_entries[i].nh_parent = old; rcu_assign_pointer(old->nh_grp, newg); /* Make sure concurrent readers are not using 'oldg' anymore. */ synchronize_net(); if (newg->resilient) { rcu_assign_pointer(oldg->res_table, tmp_table); rcu_assign_pointer(oldg->spare->res_table, tmp_table); } for (i = 0; i < oldg->num_nh; i++) oldg->nh_entries[i].nh_parent = new; rcu_assign_pointer(new->nh_grp, oldg); return 0; } static void nh_group_v4_update(struct nh_group *nhg) { struct nh_grp_entry *nhges; bool has_v4 = false; int i; nhges = nhg->nh_entries; for (i = 0; i < nhg->num_nh; i++) { struct nh_info *nhi; nhi = rtnl_dereference(nhges[i].nh->nh_info); if (nhi->family == AF_INET) has_v4 = true; } nhg->has_v4 = has_v4; } static int replace_nexthop_single_notify_res(struct net *net, struct nh_res_table *res_table, struct nexthop *old, struct nh_info *oldi, struct nh_info *newi, struct netlink_ext_ack *extack) { u32 nhg_id = res_table->nhg_id; int err; u16 i; for (i = 0; i < res_table->num_nh_buckets; i++) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; struct nh_grp_entry *nhge; nhge = rtnl_dereference(bucket->nh_entry); if (nhge->nh == old) { err = __call_nexthop_res_bucket_notifiers(net, nhg_id, i, true, oldi, newi, extack); if (err) goto err_notify; } } return 0; err_notify: while (i-- > 0) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; struct nh_grp_entry *nhge; nhge = rtnl_dereference(bucket->nh_entry); if (nhge->nh == old) __call_nexthop_res_bucket_notifiers(net, nhg_id, i, true, newi, oldi, extack); } return err; } static int replace_nexthop_single_notify(struct net *net, struct nexthop *group_nh, struct nexthop *old, struct nh_info *oldi, struct nh_info *newi, struct netlink_ext_ack *extack) { struct nh_group *nhg = rtnl_dereference(group_nh->nh_grp); struct nh_res_table *res_table; if (nhg->hash_threshold) { return call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, group_nh, extack); } else if (nhg->resilient) { res_table = rtnl_dereference(nhg->res_table); return replace_nexthop_single_notify_res(net, res_table, old, oldi, newi, extack); } return -EINVAL; } static int replace_nexthop_single(struct net *net, struct nexthop *old, struct nexthop *new, struct netlink_ext_ack *extack) { u8 old_protocol, old_nh_flags; struct nh_info *oldi, *newi; struct nh_grp_entry *nhge; int err; if (new->is_group) { NL_SET_ERR_MSG(extack, "Can not replace a nexthop with a nexthop group."); return -EINVAL; } err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new, extack); if (err) return err; /* Hardware flags were set on 'old' as 'new' is not in the red-black * tree. Therefore, inherit the flags from 'old' to 'new'. */ new->nh_flags |= old->nh_flags & (RTNH_F_OFFLOAD | RTNH_F_TRAP); oldi = rtnl_dereference(old->nh_info); newi = rtnl_dereference(new->nh_info); newi->nh_parent = old; oldi->nh_parent = new; old_protocol = old->protocol; old_nh_flags = old->nh_flags; old->protocol = new->protocol; old->nh_flags = new->nh_flags; rcu_assign_pointer(old->nh_info, newi); rcu_assign_pointer(new->nh_info, oldi); /* Send a replace notification for all the groups using the nexthop. */ list_for_each_entry(nhge, &old->grp_list, nh_list) { struct nexthop *nhp = nhge->nh_parent; err = replace_nexthop_single_notify(net, nhp, old, oldi, newi, extack); if (err) goto err_notify; } /* When replacing an IPv4 nexthop with an IPv6 nexthop, potentially * update IPv4 indication in all the groups using the nexthop. */ if (oldi->family == AF_INET && newi->family == AF_INET6) { list_for_each_entry(nhge, &old->grp_list, nh_list) { struct nexthop *nhp = nhge->nh_parent; struct nh_group *nhg; nhg = rtnl_dereference(nhp->nh_grp); nh_group_v4_update(nhg); } } return 0; err_notify: rcu_assign_pointer(new->nh_info, newi); rcu_assign_pointer(old->nh_info, oldi); old->nh_flags = old_nh_flags; old->protocol = old_protocol; oldi->nh_parent = old; newi->nh_parent = new; list_for_each_entry_continue_reverse(nhge, &old->grp_list, nh_list) { struct nexthop *nhp = nhge->nh_parent; replace_nexthop_single_notify(net, nhp, old, newi, oldi, NULL); } call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, old, extack); return err; } static void __nexthop_replace_notify(struct net *net, struct nexthop *nh, struct nl_info *info) { struct fib6_info *f6i; if (!list_empty(&nh->fi_list)) { struct fib_info *fi; /* expectation is a few fib_info per nexthop and then * a lot of routes per fib_info. So mark the fib_info * and then walk the fib tables once */ list_for_each_entry(fi, &nh->fi_list, nh_list) fi->nh_updated = true; fib_info_notify_update(net, info); list_for_each_entry(fi, &nh->fi_list, nh_list) fi->nh_updated = false; } list_for_each_entry(f6i, &nh->f6i_list, nh_list) ipv6_stub->fib6_rt_update(net, f6i, info); } /* send RTM_NEWROUTE with REPLACE flag set for all FIB entries * linked to this nexthop and for all groups that the nexthop * is a member of */ static void nexthop_replace_notify(struct net *net, struct nexthop *nh, struct nl_info *info) { struct nh_grp_entry *nhge; __nexthop_replace_notify(net, nh, info); list_for_each_entry(nhge, &nh->grp_list, nh_list) __nexthop_replace_notify(net, nhge->nh_parent, info); } static int replace_nexthop(struct net *net, struct nexthop *old, struct nexthop *new, const struct nh_config *cfg, struct netlink_ext_ack *extack) { bool new_is_reject = false; struct nh_grp_entry *nhge; int err; /* check that existing FIB entries are ok with the * new nexthop definition */ err = fib_check_nh_list(old, new, extack); if (err) return err; err = fib6_check_nh_list(old, new, extack); if (err) return err; if (!new->is_group) { struct nh_info *nhi = rtnl_dereference(new->nh_info); new_is_reject = nhi->reject_nh; } list_for_each_entry(nhge, &old->grp_list, nh_list) { /* if new nexthop is a blackhole, any groups using this * nexthop cannot have more than 1 path */ if (new_is_reject && nexthop_num_path(nhge->nh_parent) > 1) { NL_SET_ERR_MSG(extack, "Blackhole nexthop can not be a member of a group with more than one path"); return -EINVAL; } err = fib_check_nh_list(nhge->nh_parent, new, extack); if (err) return err; err = fib6_check_nh_list(nhge->nh_parent, new, extack); if (err) return err; } if (old->is_group) err = replace_nexthop_grp(net, old, new, cfg, extack); else err = replace_nexthop_single(net, old, new, extack); if (!err) { nh_rt_cache_flush(net, old, new); __remove_nexthop(net, new, NULL); nexthop_put(new); } return err; } /* called with rtnl_lock held */ static int insert_nexthop(struct net *net, struct nexthop *new_nh, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct rb_node **pp, *parent = NULL, *next; struct rb_root *root = &net->nexthop.rb_root; bool replace = !!(cfg->nlflags & NLM_F_REPLACE); bool create = !!(cfg->nlflags & NLM_F_CREATE); u32 new_id = new_nh->id; int replace_notify = 0; int rc = -EEXIST; pp = &root->rb_node; while (1) { struct nexthop *nh; next = *pp; if (!next) break; parent = next; nh = rb_entry(parent, struct nexthop, rb_node); if (new_id < nh->id) { pp = &next->rb_left; } else if (new_id > nh->id) { pp = &next->rb_right; } else if (replace) { rc = replace_nexthop(net, nh, new_nh, cfg, extack); if (!rc) { new_nh = nh; /* send notification with old nh */ replace_notify = 1; } goto out; } else { /* id already exists and not a replace */ goto out; } } if (replace && !create) { NL_SET_ERR_MSG(extack, "Replace specified without create and no entry exists"); rc = -ENOENT; goto out; } if (new_nh->is_group) { struct nh_group *nhg = rtnl_dereference(new_nh->nh_grp); struct nh_res_table *res_table; if (nhg->resilient) { res_table = rtnl_dereference(nhg->res_table); /* Not passing the number of buckets is OK when * replacing, but not when creating a new group. */ if (!cfg->nh_grp_res_has_num_buckets) { NL_SET_ERR_MSG(extack, "Number of buckets not specified for nexthop group insertion"); rc = -EINVAL; goto out; } nh_res_group_rebalance(nhg, res_table); /* Do not send bucket notifications, we do full * notification below. */ nh_res_table_upkeep(res_table, false, false); } } rb_link_node_rcu(&new_nh->rb_node, parent, pp); rb_insert_color(&new_nh->rb_node, root); /* The initial insertion is a full notification for hash-threshold as * well as resilient groups. */ rc = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new_nh, extack); if (rc) rb_erase(&new_nh->rb_node, &net->nexthop.rb_root); out: if (!rc) { nh_base_seq_inc(net); nexthop_notify(RTM_NEWNEXTHOP, new_nh, &cfg->nlinfo); if (replace_notify && READ_ONCE(net->ipv4.sysctl_nexthop_compat_mode)) nexthop_replace_notify(net, new_nh, &cfg->nlinfo); } return rc; } /* rtnl */ /* remove all nexthops tied to a device being deleted */ static void nexthop_flush_dev(struct net_device *dev, unsigned long event) { unsigned int hash = nh_dev_hashfn(dev->ifindex); struct net *net = dev_net(dev); struct hlist_head *head = &net->nexthop.devhash[hash]; struct hlist_node *n; struct nh_info *nhi; hlist_for_each_entry_safe(nhi, n, head, dev_hash) { if (nhi->fib_nhc.nhc_dev != dev) continue; if (nhi->reject_nh && (event == NETDEV_DOWN || event == NETDEV_CHANGE)) continue; remove_nexthop(net, nhi->nh_parent, NULL); } } /* rtnl; called when net namespace is deleted */ static void flush_all_nexthops(struct net *net) { struct rb_root *root = &net->nexthop.rb_root; struct rb_node *node; struct nexthop *nh; while ((node = rb_first(root))) { nh = rb_entry(node, struct nexthop, rb_node); remove_nexthop(net, nh, NULL); cond_resched(); } } static struct nexthop *nexthop_create_group(struct net *net, struct nh_config *cfg) { struct nlattr *grps_attr = cfg->nh_grp; struct nexthop_grp *entry = nla_data(grps_attr); u16 num_nh = nla_len(grps_attr) / sizeof(*entry); struct nh_group *nhg; struct nexthop *nh; int err; int i; if (WARN_ON(!num_nh)) return ERR_PTR(-EINVAL); nh = nexthop_alloc(); if (!nh) return ERR_PTR(-ENOMEM); nh->is_group = 1; nhg = nexthop_grp_alloc(num_nh); if (!nhg) { kfree(nh); return ERR_PTR(-ENOMEM); } /* spare group used for removals */ nhg->spare = nexthop_grp_alloc(num_nh); if (!nhg->spare) { kfree(nhg); kfree(nh); return ERR_PTR(-ENOMEM); } nhg->spare->spare = nhg; for (i = 0; i < nhg->num_nh; ++i) { struct nexthop *nhe; struct nh_info *nhi; nhe = nexthop_find_by_id(net, entry[i].id); if (!nexthop_get(nhe)) { err = -ENOENT; goto out_no_nh; } nhi = rtnl_dereference(nhe->nh_info); if (nhi->family == AF_INET) nhg->has_v4 = true; nhg->nh_entries[i].nh = nhe; nhg->nh_entries[i].weight = entry[i].weight + 1; list_add(&nhg->nh_entries[i].nh_list, &nhe->grp_list); nhg->nh_entries[i].nh_parent = nh; } if (cfg->nh_grp_type == NEXTHOP_GRP_TYPE_MPATH) { nhg->hash_threshold = 1; nhg->is_multipath = true; } else if (cfg->nh_grp_type == NEXTHOP_GRP_TYPE_RES) { struct nh_res_table *res_table; res_table = nexthop_res_table_alloc(net, cfg->nh_id, cfg); if (!res_table) { err = -ENOMEM; goto out_no_nh; } rcu_assign_pointer(nhg->spare->res_table, res_table); rcu_assign_pointer(nhg->res_table, res_table); nhg->resilient = true; nhg->is_multipath = true; } WARN_ON_ONCE(nhg->hash_threshold + nhg->resilient != 1); if (nhg->hash_threshold) nh_hthr_group_rebalance(nhg); if (cfg->nh_fdb) nhg->fdb_nh = 1; rcu_assign_pointer(nh->nh_grp, nhg); return nh; out_no_nh: for (i--; i >= 0; --i) { list_del(&nhg->nh_entries[i].nh_list); nexthop_put(nhg->nh_entries[i].nh); } kfree(nhg->spare); kfree(nhg); kfree(nh); return ERR_PTR(err); } static int nh_create_ipv4(struct net *net, struct nexthop *nh, struct nh_info *nhi, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct fib_nh *fib_nh = &nhi->fib_nh; struct fib_config fib_cfg = { .fc_oif = cfg->nh_ifindex, .fc_gw4 = cfg->gw.ipv4, .fc_gw_family = cfg->gw.ipv4 ? AF_INET : 0, .fc_flags = cfg->nh_flags, .fc_nlinfo = cfg->nlinfo, .fc_encap = cfg->nh_encap, .fc_encap_type = cfg->nh_encap_type, }; u32 tb_id = (cfg->dev ? l3mdev_fib_table(cfg->dev) : RT_TABLE_MAIN); int err; err = fib_nh_init(net, fib_nh, &fib_cfg, 1, extack); if (err) { fib_nh_release(net, fib_nh); goto out; } if (nhi->fdb_nh) goto out; /* sets nh_dev if successful */ err = fib_check_nh(net, fib_nh, tb_id, 0, extack); if (!err) { nh->nh_flags = fib_nh->fib_nh_flags; fib_info_update_nhc_saddr(net, &fib_nh->nh_common, !fib_nh->fib_nh_scope ? 0 : fib_nh->fib_nh_scope - 1); } else { fib_nh_release(net, fib_nh); } out: return err; } static int nh_create_ipv6(struct net *net, struct nexthop *nh, struct nh_info *nhi, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct fib6_nh *fib6_nh = &nhi->fib6_nh; struct fib6_config fib6_cfg = { .fc_table = l3mdev_fib_table(cfg->dev), .fc_ifindex = cfg->nh_ifindex, .fc_gateway = cfg->gw.ipv6, .fc_flags = cfg->nh_flags, .fc_nlinfo = cfg->nlinfo, .fc_encap = cfg->nh_encap, .fc_encap_type = cfg->nh_encap_type, .fc_is_fdb = cfg->nh_fdb, }; int err; if (!ipv6_addr_any(&cfg->gw.ipv6)) fib6_cfg.fc_flags |= RTF_GATEWAY; /* sets nh_dev if successful */ err = ipv6_stub->fib6_nh_init(net, fib6_nh, &fib6_cfg, GFP_KERNEL, extack); if (err) { /* IPv6 is not enabled, don't call fib6_nh_release */ if (err == -EAFNOSUPPORT) goto out; ipv6_stub->fib6_nh_release(fib6_nh); } else { nh->nh_flags = fib6_nh->fib_nh_flags; } out: return err; } static struct nexthop *nexthop_create(struct net *net, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nh_info *nhi; struct nexthop *nh; int err = 0; nh = nexthop_alloc(); if (!nh) return ERR_PTR(-ENOMEM); nhi = kzalloc(sizeof(*nhi), GFP_KERNEL); if (!nhi) { kfree(nh); return ERR_PTR(-ENOMEM); } nh->nh_flags = cfg->nh_flags; nh->net = net; nhi->nh_parent = nh; nhi->family = cfg->nh_family; nhi->fib_nhc.nhc_scope = RT_SCOPE_LINK; if (cfg->nh_fdb) nhi->fdb_nh = 1; if (cfg->nh_blackhole) { nhi->reject_nh = 1; cfg->nh_ifindex = net->loopback_dev->ifindex; } switch (cfg->nh_family) { case AF_INET: err = nh_create_ipv4(net, nh, nhi, cfg, extack); break; case AF_INET6: err = nh_create_ipv6(net, nh, nhi, cfg, extack); break; } if (err) { kfree(nhi); kfree(nh); return ERR_PTR(err); } /* add the entry to the device based hash */ if (!nhi->fdb_nh) nexthop_devhash_add(net, nhi); rcu_assign_pointer(nh->nh_info, nhi); return nh; } /* called with rtnl lock held */ static struct nexthop *nexthop_add(struct net *net, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nexthop *nh; int err; if (cfg->nlflags & NLM_F_REPLACE && !cfg->nh_id) { NL_SET_ERR_MSG(extack, "Replace requires nexthop id"); return ERR_PTR(-EINVAL); } if (!cfg->nh_id) { cfg->nh_id = nh_find_unused_id(net); if (!cfg->nh_id) { NL_SET_ERR_MSG(extack, "No unused id"); return ERR_PTR(-EINVAL); } } if (cfg->nh_grp) nh = nexthop_create_group(net, cfg); else nh = nexthop_create(net, cfg, extack); if (IS_ERR(nh)) return nh; refcount_set(&nh->refcnt, 1); nh->id = cfg->nh_id; nh->protocol = cfg->nh_protocol; nh->net = net; err = insert_nexthop(net, nh, cfg, extack); if (err) { __remove_nexthop(net, nh, NULL); nexthop_put(nh); nh = ERR_PTR(err); } return nh; } static int rtm_nh_get_timer(struct nlattr *attr, unsigned long fallback, unsigned long *timer_p, bool *has_p, struct netlink_ext_ack *extack) { unsigned long timer; u32 value; if (!attr) { *timer_p = fallback; *has_p = false; return 0; } value = nla_get_u32(attr); timer = clock_t_to_jiffies(value); if (timer == ~0UL) { NL_SET_ERR_MSG(extack, "Timer value too large"); return -EINVAL; } *timer_p = timer; *has_p = true; return 0; } static int rtm_to_nh_config_grp_res(struct nlattr *res, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_res_policy_new)] = {}; int err; if (res) { err = nla_parse_nested(tb, ARRAY_SIZE(rtm_nh_res_policy_new) - 1, res, rtm_nh_res_policy_new, extack); if (err < 0) return err; } if (tb[NHA_RES_GROUP_BUCKETS]) { cfg->nh_grp_res_num_buckets = nla_get_u16(tb[NHA_RES_GROUP_BUCKETS]); cfg->nh_grp_res_has_num_buckets = true; if (!cfg->nh_grp_res_num_buckets) { NL_SET_ERR_MSG(extack, "Number of buckets needs to be non-0"); return -EINVAL; } } err = rtm_nh_get_timer(tb[NHA_RES_GROUP_IDLE_TIMER], NH_RES_DEFAULT_IDLE_TIMER, &cfg->nh_grp_res_idle_timer, &cfg->nh_grp_res_has_idle_timer, extack); if (err) return err; return rtm_nh_get_timer(tb[NHA_RES_GROUP_UNBALANCED_TIMER], NH_RES_DEFAULT_UNBALANCED_TIMER, &cfg->nh_grp_res_unbalanced_timer, &cfg->nh_grp_res_has_unbalanced_timer, extack); } static int rtm_to_nh_config(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nhmsg *nhm = nlmsg_data(nlh); struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_new)]; int err; err = nlmsg_parse(nlh, sizeof(*nhm), tb, ARRAY_SIZE(rtm_nh_policy_new) - 1, rtm_nh_policy_new, extack); if (err < 0) return err; err = -EINVAL; if (nhm->resvd || nhm->nh_scope) { NL_SET_ERR_MSG(extack, "Invalid values in ancillary header"); goto out; } if (nhm->nh_flags & ~NEXTHOP_VALID_USER_FLAGS) { NL_SET_ERR_MSG(extack, "Invalid nexthop flags in ancillary header"); goto out; } switch (nhm->nh_family) { case AF_INET: case AF_INET6: break; case AF_UNSPEC: if (tb[NHA_GROUP]) break; fallthrough; default: NL_SET_ERR_MSG(extack, "Invalid address family"); goto out; } memset(cfg, 0, sizeof(*cfg)); cfg->nlflags = nlh->nlmsg_flags; cfg->nlinfo.portid = NETLINK_CB(skb).portid; cfg->nlinfo.nlh = nlh; cfg->nlinfo.nl_net = net; cfg->nh_family = nhm->nh_family; cfg->nh_protocol = nhm->nh_protocol; cfg->nh_flags = nhm->nh_flags; if (tb[NHA_ID]) cfg->nh_id = nla_get_u32(tb[NHA_ID]); if (tb[NHA_FDB]) { if (tb[NHA_OIF] || tb[NHA_BLACKHOLE] || tb[NHA_ENCAP] || tb[NHA_ENCAP_TYPE]) { NL_SET_ERR_MSG(extack, "Fdb attribute can not be used with encap, oif or blackhole"); goto out; } if (nhm->nh_flags) { NL_SET_ERR_MSG(extack, "Unsupported nexthop flags in ancillary header"); goto out; } cfg->nh_fdb = nla_get_flag(tb[NHA_FDB]); } if (tb[NHA_GROUP]) { if (nhm->nh_family != AF_UNSPEC) { NL_SET_ERR_MSG(extack, "Invalid family for group"); goto out; } cfg->nh_grp = tb[NHA_GROUP]; cfg->nh_grp_type = NEXTHOP_GRP_TYPE_MPATH; if (tb[NHA_GROUP_TYPE]) cfg->nh_grp_type = nla_get_u16(tb[NHA_GROUP_TYPE]); if (cfg->nh_grp_type > NEXTHOP_GRP_TYPE_MAX) { NL_SET_ERR_MSG(extack, "Invalid group type"); goto out; } err = nh_check_attr_group(net, tb, ARRAY_SIZE(tb), cfg->nh_grp_type, extack); if (err) goto out; if (cfg->nh_grp_type == NEXTHOP_GRP_TYPE_RES) err = rtm_to_nh_config_grp_res(tb[NHA_RES_GROUP], cfg, extack); /* no other attributes should be set */ goto out; } if (tb[NHA_BLACKHOLE]) { if (tb[NHA_GATEWAY] || tb[NHA_OIF] || tb[NHA_ENCAP] || tb[NHA_ENCAP_TYPE] || tb[NHA_FDB]) { NL_SET_ERR_MSG(extack, "Blackhole attribute can not be used with gateway, oif, encap or fdb"); goto out; } cfg->nh_blackhole = 1; err = 0; goto out; } if (!cfg->nh_fdb && !tb[NHA_OIF]) { NL_SET_ERR_MSG(extack, "Device attribute required for non-blackhole and non-fdb nexthops"); goto out; } if (!cfg->nh_fdb && tb[NHA_OIF]) { cfg->nh_ifindex = nla_get_u32(tb[NHA_OIF]); if (cfg->nh_ifindex) cfg->dev = __dev_get_by_index(net, cfg->nh_ifindex); if (!cfg->dev) { NL_SET_ERR_MSG(extack, "Invalid device index"); goto out; } else if (!(cfg->dev->flags & IFF_UP)) { NL_SET_ERR_MSG(extack, "Nexthop device is not up"); err = -ENETDOWN; goto out; } else if (!netif_carrier_ok(cfg->dev)) { NL_SET_ERR_MSG(extack, "Carrier for nexthop device is down"); err = -ENETDOWN; goto out; } } err = -EINVAL; if (tb[NHA_GATEWAY]) { struct nlattr *gwa = tb[NHA_GATEWAY]; switch (cfg->nh_family) { case AF_INET: if (nla_len(gwa) != sizeof(u32)) { NL_SET_ERR_MSG(extack, "Invalid gateway"); goto out; } cfg->gw.ipv4 = nla_get_be32(gwa); break; case AF_INET6: if (nla_len(gwa) != sizeof(struct in6_addr)) { NL_SET_ERR_MSG(extack, "Invalid gateway"); goto out; } cfg->gw.ipv6 = nla_get_in6_addr(gwa); break; default: NL_SET_ERR_MSG(extack, "Unknown address family for gateway"); goto out; } } else { /* device only nexthop (no gateway) */ if (cfg->nh_flags & RTNH_F_ONLINK) { NL_SET_ERR_MSG(extack, "ONLINK flag can not be set for nexthop without a gateway"); goto out; } } if (tb[NHA_ENCAP]) { cfg->nh_encap = tb[NHA_ENCAP]; if (!tb[NHA_ENCAP_TYPE]) { NL_SET_ERR_MSG(extack, "LWT encapsulation type is missing"); goto out; } cfg->nh_encap_type = nla_get_u16(tb[NHA_ENCAP_TYPE]); err = lwtunnel_valid_encap_type(cfg->nh_encap_type, extack); if (err < 0) goto out; } else if (tb[NHA_ENCAP_TYPE]) { NL_SET_ERR_MSG(extack, "LWT encapsulation attribute is missing"); goto out; } err = 0; out: return err; } /* rtnl */ static int rtm_new_nexthop(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct nh_config cfg; struct nexthop *nh; int err; err = rtm_to_nh_config(net, skb, nlh, &cfg, extack); if (!err) { nh = nexthop_add(net, &cfg, extack); if (IS_ERR(nh)) err = PTR_ERR(nh); } return err; } static int __nh_valid_get_del_req(const struct nlmsghdr *nlh, struct nlattr **tb, u32 *id, struct netlink_ext_ack *extack) { struct nhmsg *nhm = nlmsg_data(nlh); if (nhm->nh_protocol || nhm->resvd || nhm->nh_scope || nhm->nh_flags) { NL_SET_ERR_MSG(extack, "Invalid values in header"); return -EINVAL; } if (!tb[NHA_ID]) { NL_SET_ERR_MSG(extack, "Nexthop id is missing"); return -EINVAL; } *id = nla_get_u32(tb[NHA_ID]); if (!(*id)) { NL_SET_ERR_MSG(extack, "Invalid nexthop id"); return -EINVAL; } return 0; } static int nh_valid_get_del_req(const struct nlmsghdr *nlh, u32 *id, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_get)]; int err; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_get) - 1, rtm_nh_policy_get, extack); if (err < 0) return err; return __nh_valid_get_del_req(nlh, tb, id, extack); } /* rtnl */ static int rtm_del_nexthop(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct nl_info nlinfo = { .nlh = nlh, .nl_net = net, .portid = NETLINK_CB(skb).portid, }; struct nexthop *nh; int err; u32 id; err = nh_valid_get_del_req(nlh, &id, extack); if (err) return err; nh = nexthop_find_by_id(net, id); if (!nh) return -ENOENT; remove_nexthop(net, nh, &nlinfo); return 0; } /* rtnl */ static int rtm_get_nexthop(struct sk_buff *in_skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(in_skb->sk); struct sk_buff *skb = NULL; struct nexthop *nh; int err; u32 id; err = nh_valid_get_del_req(nlh, &id, extack); if (err) return err; err = -ENOBUFS; skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) goto out; err = -ENOENT; nh = nexthop_find_by_id(net, id); if (!nh) goto errout_free; err = nh_fill_node(skb, nh, RTM_NEWNEXTHOP, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, 0); if (err < 0) { WARN_ON(err == -EMSGSIZE); goto errout_free; } err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); out: return err; errout_free: kfree_skb(skb); goto out; } struct nh_dump_filter { u32 nh_id; int dev_idx; int master_idx; bool group_filter; bool fdb_filter; u32 res_bucket_nh_id; }; static bool nh_dump_filtered(struct nexthop *nh, struct nh_dump_filter *filter, u8 family) { const struct net_device *dev; const struct nh_info *nhi; if (filter->group_filter && !nh->is_group) return true; if (!filter->dev_idx && !filter->master_idx && !family) return false; if (nh->is_group) return true; nhi = rtnl_dereference(nh->nh_info); if (family && nhi->family != family) return true; dev = nhi->fib_nhc.nhc_dev; if (filter->dev_idx && (!dev || dev->ifindex != filter->dev_idx)) return true; if (filter->master_idx) { struct net_device *master; if (!dev) return true; master = netdev_master_upper_dev_get((struct net_device *)dev); if (!master || master->ifindex != filter->master_idx) return true; } return false; } static int __nh_valid_dump_req(const struct nlmsghdr *nlh, struct nlattr **tb, struct nh_dump_filter *filter, struct netlink_ext_ack *extack) { struct nhmsg *nhm; u32 idx; if (tb[NHA_OIF]) { idx = nla_get_u32(tb[NHA_OIF]); if (idx > INT_MAX) { NL_SET_ERR_MSG(extack, "Invalid device index"); return -EINVAL; } filter->dev_idx = idx; } if (tb[NHA_MASTER]) { idx = nla_get_u32(tb[NHA_MASTER]); if (idx > INT_MAX) { NL_SET_ERR_MSG(extack, "Invalid master device index"); return -EINVAL; } filter->master_idx = idx; } filter->group_filter = nla_get_flag(tb[NHA_GROUPS]); filter->fdb_filter = nla_get_flag(tb[NHA_FDB]); nhm = nlmsg_data(nlh); if (nhm->nh_protocol || nhm->resvd || nhm->nh_scope || nhm->nh_flags) { NL_SET_ERR_MSG(extack, "Invalid values in header for nexthop dump request"); return -EINVAL; } return 0; } static int nh_valid_dump_req(const struct nlmsghdr *nlh, struct nh_dump_filter *filter, struct netlink_callback *cb) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_dump)]; int err; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_dump) - 1, rtm_nh_policy_dump, cb->extack); if (err < 0) return err; return __nh_valid_dump_req(nlh, tb, filter, cb->extack); } struct rtm_dump_nh_ctx { u32 idx; }; static struct rtm_dump_nh_ctx * rtm_dump_nh_ctx(struct netlink_callback *cb) { struct rtm_dump_nh_ctx *ctx = (void *)cb->ctx; BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx)); return ctx; } static int rtm_dump_walk_nexthops(struct sk_buff *skb, struct netlink_callback *cb, struct rb_root *root, struct rtm_dump_nh_ctx *ctx, int (*nh_cb)(struct sk_buff *skb, struct netlink_callback *cb, struct nexthop *nh, void *data), void *data) { struct rb_node *node; int s_idx; int err; s_idx = ctx->idx; for (node = rb_first(root); node; node = rb_next(node)) { struct nexthop *nh; nh = rb_entry(node, struct nexthop, rb_node); if (nh->id < s_idx) continue; ctx->idx = nh->id; err = nh_cb(skb, cb, nh, data); if (err) return err; } return 0; } static int rtm_dump_nexthop_cb(struct sk_buff *skb, struct netlink_callback *cb, struct nexthop *nh, void *data) { struct nhmsg *nhm = nlmsg_data(cb->nlh); struct nh_dump_filter *filter = data; if (nh_dump_filtered(nh, filter, nhm->nh_family)) return 0; return nh_fill_node(skb, nh, RTM_NEWNEXTHOP, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI); } /* rtnl */ static int rtm_dump_nexthop(struct sk_buff *skb, struct netlink_callback *cb) { struct rtm_dump_nh_ctx *ctx = rtm_dump_nh_ctx(cb); struct net *net = sock_net(skb->sk); struct rb_root *root = &net->nexthop.rb_root; struct nh_dump_filter filter = {}; int err; err = nh_valid_dump_req(cb->nlh, &filter, cb); if (err < 0) return err; err = rtm_dump_walk_nexthops(skb, cb, root, ctx, &rtm_dump_nexthop_cb, &filter); if (err < 0) { if (likely(skb->len)) err = skb->len; } cb->seq = net->nexthop.seq; nl_dump_check_consistent(cb, nlmsg_hdr(skb)); return err; } static struct nexthop * nexthop_find_group_resilient(struct net *net, u32 id, struct netlink_ext_ack *extack) { struct nh_group *nhg; struct nexthop *nh; nh = nexthop_find_by_id(net, id); if (!nh) return ERR_PTR(-ENOENT); if (!nh->is_group) { NL_SET_ERR_MSG(extack, "Not a nexthop group"); return ERR_PTR(-EINVAL); } nhg = rtnl_dereference(nh->nh_grp); if (!nhg->resilient) { NL_SET_ERR_MSG(extack, "Nexthop group not of type resilient"); return ERR_PTR(-EINVAL); } return nh; } static int nh_valid_dump_nhid(struct nlattr *attr, u32 *nh_id_p, struct netlink_ext_ack *extack) { u32 idx; if (attr) { idx = nla_get_u32(attr); if (!idx) { NL_SET_ERR_MSG(extack, "Invalid nexthop id"); return -EINVAL; } *nh_id_p = idx; } else { *nh_id_p = 0; } return 0; } static int nh_valid_dump_bucket_req(const struct nlmsghdr *nlh, struct nh_dump_filter *filter, struct netlink_callback *cb) { struct nlattr *res_tb[ARRAY_SIZE(rtm_nh_res_bucket_policy_dump)]; struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_dump_bucket)]; int err; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_dump_bucket) - 1, rtm_nh_policy_dump_bucket, NULL); if (err < 0) return err; err = nh_valid_dump_nhid(tb[NHA_ID], &filter->nh_id, cb->extack); if (err) return err; if (tb[NHA_RES_BUCKET]) { size_t max = ARRAY_SIZE(rtm_nh_res_bucket_policy_dump) - 1; err = nla_parse_nested(res_tb, max, tb[NHA_RES_BUCKET], rtm_nh_res_bucket_policy_dump, cb->extack); if (err < 0) return err; err = nh_valid_dump_nhid(res_tb[NHA_RES_BUCKET_NH_ID], &filter->res_bucket_nh_id, cb->extack); if (err) return err; } return __nh_valid_dump_req(nlh, tb, filter, cb->extack); } struct rtm_dump_res_bucket_ctx { struct rtm_dump_nh_ctx nh; u16 bucket_index; }; static struct rtm_dump_res_bucket_ctx * rtm_dump_res_bucket_ctx(struct netlink_callback *cb) { struct rtm_dump_res_bucket_ctx *ctx = (void *)cb->ctx; BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx)); return ctx; } struct rtm_dump_nexthop_bucket_data { struct rtm_dump_res_bucket_ctx *ctx; struct nh_dump_filter filter; }; static int rtm_dump_nexthop_bucket_nh(struct sk_buff *skb, struct netlink_callback *cb, struct nexthop *nh, struct rtm_dump_nexthop_bucket_data *dd) { u32 portid = NETLINK_CB(cb->skb).portid; struct nhmsg *nhm = nlmsg_data(cb->nlh); struct nh_res_table *res_table; struct nh_group *nhg; u16 bucket_index; int err; nhg = rtnl_dereference(nh->nh_grp); res_table = rtnl_dereference(nhg->res_table); for (bucket_index = dd->ctx->bucket_index; bucket_index < res_table->num_nh_buckets; bucket_index++) { struct nh_res_bucket *bucket; struct nh_grp_entry *nhge; bucket = &res_table->nh_buckets[bucket_index]; nhge = rtnl_dereference(bucket->nh_entry); if (nh_dump_filtered(nhge->nh, &dd->filter, nhm->nh_family)) continue; if (dd->filter.res_bucket_nh_id && dd->filter.res_bucket_nh_id != nhge->nh->id) continue; dd->ctx->bucket_index = bucket_index; err = nh_fill_res_bucket(skb, nh, bucket, bucket_index, RTM_NEWNEXTHOPBUCKET, portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->extack); if (err) return err; } dd->ctx->bucket_index = 0; return 0; } static int rtm_dump_nexthop_bucket_cb(struct sk_buff *skb, struct netlink_callback *cb, struct nexthop *nh, void *data) { struct rtm_dump_nexthop_bucket_data *dd = data; struct nh_group *nhg; if (!nh->is_group) return 0; nhg = rtnl_dereference(nh->nh_grp); if (!nhg->resilient) return 0; return rtm_dump_nexthop_bucket_nh(skb, cb, nh, dd); } /* rtnl */ static int rtm_dump_nexthop_bucket(struct sk_buff *skb, struct netlink_callback *cb) { struct rtm_dump_res_bucket_ctx *ctx = rtm_dump_res_bucket_ctx(cb); struct rtm_dump_nexthop_bucket_data dd = { .ctx = ctx }; struct net *net = sock_net(skb->sk); struct nexthop *nh; int err; err = nh_valid_dump_bucket_req(cb->nlh, &dd.filter, cb); if (err) return err; if (dd.filter.nh_id) { nh = nexthop_find_group_resilient(net, dd.filter.nh_id, cb->extack); if (IS_ERR(nh)) return PTR_ERR(nh); err = rtm_dump_nexthop_bucket_nh(skb, cb, nh, &dd); } else { struct rb_root *root = &net->nexthop.rb_root; err = rtm_dump_walk_nexthops(skb, cb, root, &ctx->nh, &rtm_dump_nexthop_bucket_cb, &dd); } if (err < 0) { if (likely(skb->len)) err = skb->len; } cb->seq = net->nexthop.seq; nl_dump_check_consistent(cb, nlmsg_hdr(skb)); return err; } static int nh_valid_get_bucket_req_res_bucket(struct nlattr *res, u16 *bucket_index, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_res_bucket_policy_get)]; int err; err = nla_parse_nested(tb, ARRAY_SIZE(rtm_nh_res_bucket_policy_get) - 1, res, rtm_nh_res_bucket_policy_get, extack); if (err < 0) return err; if (!tb[NHA_RES_BUCKET_INDEX]) { NL_SET_ERR_MSG(extack, "Bucket index is missing"); return -EINVAL; } *bucket_index = nla_get_u16(tb[NHA_RES_BUCKET_INDEX]); return 0; } static int nh_valid_get_bucket_req(const struct nlmsghdr *nlh, u32 *id, u16 *bucket_index, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_get_bucket)]; int err; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_get_bucket) - 1, rtm_nh_policy_get_bucket, extack); if (err < 0) return err; err = __nh_valid_get_del_req(nlh, tb, id, extack); if (err) return err; if (!tb[NHA_RES_BUCKET]) { NL_SET_ERR_MSG(extack, "Bucket information is missing"); return -EINVAL; } err = nh_valid_get_bucket_req_res_bucket(tb[NHA_RES_BUCKET], bucket_index, extack); if (err) return err; return 0; } /* rtnl */ static int rtm_get_nexthop_bucket(struct sk_buff *in_skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(in_skb->sk); struct nh_res_table *res_table; struct sk_buff *skb = NULL; struct nh_group *nhg; struct nexthop *nh; u16 bucket_index; int err; u32 id; err = nh_valid_get_bucket_req(nlh, &id, &bucket_index, extack); if (err) return err; nh = nexthop_find_group_resilient(net, id, extack); if (IS_ERR(nh)) return PTR_ERR(nh); nhg = rtnl_dereference(nh->nh_grp); res_table = rtnl_dereference(nhg->res_table); if (bucket_index >= res_table->num_nh_buckets) { NL_SET_ERR_MSG(extack, "Bucket index out of bounds"); return -ENOENT; } skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return -ENOBUFS; err = nh_fill_res_bucket(skb, nh, &res_table->nh_buckets[bucket_index], bucket_index, RTM_NEWNEXTHOPBUCKET, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, 0, extack); if (err < 0) { WARN_ON(err == -EMSGSIZE); goto errout_free; } return rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); errout_free: kfree_skb(skb); return err; } static void nexthop_sync_mtu(struct net_device *dev, u32 orig_mtu) { unsigned int hash = nh_dev_hashfn(dev->ifindex); struct net *net = dev_net(dev); struct hlist_head *head = &net->nexthop.devhash[hash]; struct hlist_node *n; struct nh_info *nhi; hlist_for_each_entry_safe(nhi, n, head, dev_hash) { if (nhi->fib_nhc.nhc_dev == dev) { if (nhi->family == AF_INET) fib_nhc_update_mtu(&nhi->fib_nhc, dev->mtu, orig_mtu); } } } /* rtnl */ static int nh_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct netdev_notifier_info_ext *info_ext; switch (event) { case NETDEV_DOWN: case NETDEV_UNREGISTER: nexthop_flush_dev(dev, event); break; case NETDEV_CHANGE: if (!(dev_get_flags(dev) & (IFF_RUNNING | IFF_LOWER_UP))) nexthop_flush_dev(dev, event); break; case NETDEV_CHANGEMTU: info_ext = ptr; nexthop_sync_mtu(dev, info_ext->ext.mtu); rt_cache_flush(dev_net(dev)); break; } return NOTIFY_DONE; } static struct notifier_block nh_netdev_notifier = { .notifier_call = nh_netdev_event, }; static int nexthops_dump(struct net *net, struct notifier_block *nb, enum nexthop_event_type event_type, struct netlink_ext_ack *extack) { struct rb_root *root = &net->nexthop.rb_root; struct rb_node *node; int err = 0; for (node = rb_first(root); node; node = rb_next(node)) { struct nexthop *nh; nh = rb_entry(node, struct nexthop, rb_node); err = call_nexthop_notifier(nb, net, event_type, nh, extack); if (err) break; } return err; } int register_nexthop_notifier(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { int err; rtnl_lock(); err = nexthops_dump(net, nb, NEXTHOP_EVENT_REPLACE, extack); if (err) goto unlock; err = blocking_notifier_chain_register(&net->nexthop.notifier_chain, nb); unlock: rtnl_unlock(); return err; } EXPORT_SYMBOL(register_nexthop_notifier); int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb) { int err; rtnl_lock(); err = blocking_notifier_chain_unregister(&net->nexthop.notifier_chain, nb); if (err) goto unlock; nexthops_dump(net, nb, NEXTHOP_EVENT_DEL, NULL); unlock: rtnl_unlock(); return err; } EXPORT_SYMBOL(unregister_nexthop_notifier); void nexthop_set_hw_flags(struct net *net, u32 id, bool offload, bool trap) { struct nexthop *nexthop; rcu_read_lock(); nexthop = nexthop_find_by_id(net, id); if (!nexthop) goto out; nexthop->nh_flags &= ~(RTNH_F_OFFLOAD | RTNH_F_TRAP); if (offload) nexthop->nh_flags |= RTNH_F_OFFLOAD; if (trap) nexthop->nh_flags |= RTNH_F_TRAP; out: rcu_read_unlock(); } EXPORT_SYMBOL(nexthop_set_hw_flags); void nexthop_bucket_set_hw_flags(struct net *net, u32 id, u16 bucket_index, bool offload, bool trap) { struct nh_res_table *res_table; struct nh_res_bucket *bucket; struct nexthop *nexthop; struct nh_group *nhg; rcu_read_lock(); nexthop = nexthop_find_by_id(net, id); if (!nexthop || !nexthop->is_group) goto out; nhg = rcu_dereference(nexthop->nh_grp); if (!nhg->resilient) goto out; if (bucket_index >= nhg->res_table->num_nh_buckets) goto out; res_table = rcu_dereference(nhg->res_table); bucket = &res_table->nh_buckets[bucket_index]; bucket->nh_flags &= ~(RTNH_F_OFFLOAD | RTNH_F_TRAP); if (offload) bucket->nh_flags |= RTNH_F_OFFLOAD; if (trap) bucket->nh_flags |= RTNH_F_TRAP; out: rcu_read_unlock(); } EXPORT_SYMBOL(nexthop_bucket_set_hw_flags); void nexthop_res_grp_activity_update(struct net *net, u32 id, u16 num_buckets, unsigned long *activity) { struct nh_res_table *res_table; struct nexthop *nexthop; struct nh_group *nhg; u16 i; rcu_read_lock(); nexthop = nexthop_find_by_id(net, id); if (!nexthop || !nexthop->is_group) goto out; nhg = rcu_dereference(nexthop->nh_grp); if (!nhg->resilient) goto out; /* Instead of silently ignoring some buckets, demand that the sizes * be the same. */ res_table = rcu_dereference(nhg->res_table); if (num_buckets != res_table->num_nh_buckets) goto out; for (i = 0; i < num_buckets; i++) { if (test_bit(i, activity)) nh_res_bucket_set_busy(&res_table->nh_buckets[i]); } out: rcu_read_unlock(); } EXPORT_SYMBOL(nexthop_res_grp_activity_update); static void __net_exit nexthop_net_exit_batch(struct list_head *net_list) { struct net *net; rtnl_lock(); list_for_each_entry(net, net_list, exit_list) { flush_all_nexthops(net); kfree(net->nexthop.devhash); } rtnl_unlock(); } static int __net_init nexthop_net_init(struct net *net) { size_t sz = sizeof(struct hlist_head) * NH_DEV_HASHSIZE; net->nexthop.rb_root = RB_ROOT; net->nexthop.devhash = kzalloc(sz, GFP_KERNEL); if (!net->nexthop.devhash) return -ENOMEM; BLOCKING_INIT_NOTIFIER_HEAD(&net->nexthop.notifier_chain); return 0; } static struct pernet_operations nexthop_net_ops = { .init = nexthop_net_init, .exit_batch = nexthop_net_exit_batch, }; static int __init nexthop_init(void) { register_pernet_subsys(&nexthop_net_ops); register_netdevice_notifier(&nh_netdev_notifier); rtnl_register(PF_UNSPEC, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0); rtnl_register(PF_UNSPEC, RTM_DELNEXTHOP, rtm_del_nexthop, NULL, 0); rtnl_register(PF_UNSPEC, RTM_GETNEXTHOP, rtm_get_nexthop, rtm_dump_nexthop, 0); rtnl_register(PF_INET, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0); rtnl_register(PF_INET, RTM_GETNEXTHOP, NULL, rtm_dump_nexthop, 0); rtnl_register(PF_INET6, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0); rtnl_register(PF_INET6, RTM_GETNEXTHOP, NULL, rtm_dump_nexthop, 0); rtnl_register(PF_UNSPEC, RTM_GETNEXTHOPBUCKET, rtm_get_nexthop_bucket, rtm_dump_nexthop_bucket, 0); return 0; } subsys_initcall(nexthop_init);
linux-master
net/ipv4/nexthop.c
// SPDX-License-Identifier: GPL-2.0-only /* tunnel4.c: Generic IP tunnel transformer. * * Copyright (C) 2003 David S. Miller ([email protected]) */ #include <linux/init.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/mpls.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <linux/slab.h> #include <net/icmp.h> #include <net/ip.h> #include <net/protocol.h> #include <net/xfrm.h> static struct xfrm_tunnel __rcu *tunnel4_handlers __read_mostly; static struct xfrm_tunnel __rcu *tunnel64_handlers __read_mostly; static struct xfrm_tunnel __rcu *tunnelmpls4_handlers __read_mostly; static DEFINE_MUTEX(tunnel4_mutex); static inline struct xfrm_tunnel __rcu **fam_handlers(unsigned short family) { return (family == AF_INET) ? &tunnel4_handlers : (family == AF_INET6) ? &tunnel64_handlers : &tunnelmpls4_handlers; } int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family) { struct xfrm_tunnel __rcu **pprev; struct xfrm_tunnel *t; int ret = -EEXIST; int priority = handler->priority; mutex_lock(&tunnel4_mutex); for (pprev = fam_handlers(family); (t = rcu_dereference_protected(*pprev, lockdep_is_held(&tunnel4_mutex))) != NULL; pprev = &t->next) { if (t->priority > priority) break; if (t->priority == priority) goto err; } handler->next = *pprev; rcu_assign_pointer(*pprev, handler); ret = 0; err: mutex_unlock(&tunnel4_mutex); return ret; } EXPORT_SYMBOL(xfrm4_tunnel_register); int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family) { struct xfrm_tunnel __rcu **pprev; struct xfrm_tunnel *t; int ret = -ENOENT; mutex_lock(&tunnel4_mutex); for (pprev = fam_handlers(family); (t = rcu_dereference_protected(*pprev, lockdep_is_held(&tunnel4_mutex))) != NULL; pprev = &t->next) { if (t == handler) { *pprev = handler->next; ret = 0; break; } } mutex_unlock(&tunnel4_mutex); synchronize_net(); return ret; } EXPORT_SYMBOL(xfrm4_tunnel_deregister); #define for_each_tunnel_rcu(head, handler) \ for (handler = rcu_dereference(head); \ handler != NULL; \ handler = rcu_dereference(handler->next)) \ static int tunnel4_rcv(struct sk_buff *skb) { struct xfrm_tunnel *handler; if (!pskb_may_pull(skb, sizeof(struct iphdr))) goto drop; for_each_tunnel_rcu(tunnel4_handlers, handler) if (!handler->handler(skb)) return 0; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) static int tunnel4_rcv_cb(struct sk_buff *skb, u8 proto, int err) { struct xfrm_tunnel __rcu *head; struct xfrm_tunnel *handler; int ret; head = (proto == IPPROTO_IPIP) ? tunnel4_handlers : tunnel64_handlers; for_each_tunnel_rcu(head, handler) { if (handler->cb_handler) { ret = handler->cb_handler(skb, err); if (ret <= 0) return ret; } } return 0; } static const struct xfrm_input_afinfo tunnel4_input_afinfo = { .family = AF_INET, .is_ipip = true, .callback = tunnel4_rcv_cb, }; #endif #if IS_ENABLED(CONFIG_IPV6) static int tunnel64_rcv(struct sk_buff *skb) { struct xfrm_tunnel *handler; if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) goto drop; for_each_tunnel_rcu(tunnel64_handlers, handler) if (!handler->handler(skb)) return 0; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } #endif #if IS_ENABLED(CONFIG_MPLS) static int tunnelmpls4_rcv(struct sk_buff *skb) { struct xfrm_tunnel *handler; if (!pskb_may_pull(skb, sizeof(struct mpls_label))) goto drop; for_each_tunnel_rcu(tunnelmpls4_handlers, handler) if (!handler->handler(skb)) return 0; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } #endif static int tunnel4_err(struct sk_buff *skb, u32 info) { struct xfrm_tunnel *handler; for_each_tunnel_rcu(tunnel4_handlers, handler) if (!handler->err_handler(skb, info)) return 0; return -ENOENT; } #if IS_ENABLED(CONFIG_IPV6) static int tunnel64_err(struct sk_buff *skb, u32 info) { struct xfrm_tunnel *handler; for_each_tunnel_rcu(tunnel64_handlers, handler) if (!handler->err_handler(skb, info)) return 0; return -ENOENT; } #endif #if IS_ENABLED(CONFIG_MPLS) static int tunnelmpls4_err(struct sk_buff *skb, u32 info) { struct xfrm_tunnel *handler; for_each_tunnel_rcu(tunnelmpls4_handlers, handler) if (!handler->err_handler(skb, info)) return 0; return -ENOENT; } #endif static const struct net_protocol tunnel4_protocol = { .handler = tunnel4_rcv, .err_handler = tunnel4_err, .no_policy = 1, }; #if IS_ENABLED(CONFIG_IPV6) static const struct net_protocol tunnel64_protocol = { .handler = tunnel64_rcv, .err_handler = tunnel64_err, .no_policy = 1, }; #endif #if IS_ENABLED(CONFIG_MPLS) static const struct net_protocol tunnelmpls4_protocol = { .handler = tunnelmpls4_rcv, .err_handler = tunnelmpls4_err, .no_policy = 1, }; #endif static int __init tunnel4_init(void) { if (inet_add_protocol(&tunnel4_protocol, IPPROTO_IPIP)) goto err; #if IS_ENABLED(CONFIG_IPV6) if (inet_add_protocol(&tunnel64_protocol, IPPROTO_IPV6)) { inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP); goto err; } #endif #if IS_ENABLED(CONFIG_MPLS) if (inet_add_protocol(&tunnelmpls4_protocol, IPPROTO_MPLS)) { inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP); #if IS_ENABLED(CONFIG_IPV6) inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6); #endif goto err; } #endif #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) if (xfrm_input_register_afinfo(&tunnel4_input_afinfo)) { inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP); #if IS_ENABLED(CONFIG_IPV6) inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6); #endif #if IS_ENABLED(CONFIG_MPLS) inet_del_protocol(&tunnelmpls4_protocol, IPPROTO_MPLS); #endif goto err; } #endif return 0; err: pr_err("%s: can't add protocol\n", __func__); return -EAGAIN; } static void __exit tunnel4_fini(void) { #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) if (xfrm_input_unregister_afinfo(&tunnel4_input_afinfo)) pr_err("tunnel4 close: can't remove input afinfo\n"); #endif #if IS_ENABLED(CONFIG_MPLS) if (inet_del_protocol(&tunnelmpls4_protocol, IPPROTO_MPLS)) pr_err("tunnelmpls4 close: can't remove protocol\n"); #endif #if IS_ENABLED(CONFIG_IPV6) if (inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6)) pr_err("tunnel64 close: can't remove protocol\n"); #endif if (inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP)) pr_err("tunnel4 close: can't remove protocol\n"); } module_init(tunnel4_init); module_exit(tunnel4_fini); MODULE_LICENSE("GPL");
linux-master
net/ipv4/tunnel4.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * common UDP/RAW code * Linux INET implementation * * Authors: * Hideaki YOSHIFUJI <[email protected]> */ #include <linux/types.h> #include <linux/module.h> #include <linux/in.h> #include <net/ip.h> #include <net/sock.h> #include <net/route.h> #include <net/tcp_states.h> #include <net/sock_reuseport.h> int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { struct inet_sock *inet = inet_sk(sk); struct sockaddr_in *usin = (struct sockaddr_in *) uaddr; struct flowi4 *fl4; struct rtable *rt; __be32 saddr; int oif; int err; if (addr_len < sizeof(*usin)) return -EINVAL; if (usin->sin_family != AF_INET) return -EAFNOSUPPORT; sk_dst_reset(sk); oif = sk->sk_bound_dev_if; saddr = inet->inet_saddr; if (ipv4_is_multicast(usin->sin_addr.s_addr)) { if (!oif || netif_index_is_l3_master(sock_net(sk), oif)) oif = inet->mc_index; if (!saddr) saddr = inet->mc_addr; } else if (!oif) { oif = inet->uc_index; } fl4 = &inet->cork.fl.u.ip4; rt = ip_route_connect(fl4, usin->sin_addr.s_addr, saddr, oif, sk->sk_protocol, inet->inet_sport, usin->sin_port, sk); if (IS_ERR(rt)) { err = PTR_ERR(rt); if (err == -ENETUNREACH) IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); goto out; } if ((rt->rt_flags & RTCF_BROADCAST) && !sock_flag(sk, SOCK_BROADCAST)) { ip_rt_put(rt); err = -EACCES; goto out; } if (!inet->inet_saddr) inet->inet_saddr = fl4->saddr; /* Update source address */ if (!inet->inet_rcv_saddr) { inet->inet_rcv_saddr = fl4->saddr; if (sk->sk_prot->rehash) sk->sk_prot->rehash(sk); } inet->inet_daddr = fl4->daddr; inet->inet_dport = usin->sin_port; reuseport_has_conns_set(sk); sk->sk_state = TCP_ESTABLISHED; sk_set_txhash(sk); atomic_set(&inet->inet_id, get_random_u16()); sk_dst_set(sk, &rt->dst); err = 0; out: return err; } EXPORT_SYMBOL(__ip4_datagram_connect); int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { int res; lock_sock(sk); res = __ip4_datagram_connect(sk, uaddr, addr_len); release_sock(sk); return res; } EXPORT_SYMBOL(ip4_datagram_connect); /* Because UDP xmit path can manipulate sk_dst_cache without holding * socket lock, we need to use sk_dst_set() here, * even if we own the socket lock. */ void ip4_datagram_release_cb(struct sock *sk) { const struct inet_sock *inet = inet_sk(sk); const struct ip_options_rcu *inet_opt; __be32 daddr = inet->inet_daddr; struct dst_entry *dst; struct flowi4 fl4; struct rtable *rt; rcu_read_lock(); dst = __sk_dst_get(sk); if (!dst || !dst->obsolete || dst->ops->check(dst, 0)) { rcu_read_unlock(); return; } inet_opt = rcu_dereference(inet->inet_opt); if (inet_opt && inet_opt->opt.srr) daddr = inet_opt->opt.faddr; rt = ip_route_output_ports(sock_net(sk), &fl4, sk, daddr, inet->inet_saddr, inet->inet_dport, inet->inet_sport, sk->sk_protocol, RT_CONN_FLAGS(sk), sk->sk_bound_dev_if); dst = !IS_ERR(rt) ? &rt->dst : NULL; sk_dst_set(sk, dst); rcu_read_unlock(); } EXPORT_SYMBOL_GPL(ip4_datagram_release_cb);
linux-master
net/ipv4/datagram.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * "Ping" sockets * * Based on ipv4/udp.c code. * * Authors: Vasiliy Kulikov / Openwall (for Linux 2.6), * Pavel Kankovsky (for Linux 2.4.32) * * Pavel gave all rights to bugs to Vasiliy, * none of the bugs are Pavel's now. */ #include <linux/uaccess.h> #include <linux/types.h> #include <linux/fcntl.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/in.h> #include <linux/errno.h> #include <linux/timer.h> #include <linux/mm.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <net/snmp.h> #include <net/ip.h> #include <net/icmp.h> #include <net/protocol.h> #include <linux/skbuff.h> #include <linux/proc_fs.h> #include <linux/export.h> #include <linux/bpf-cgroup.h> #include <net/sock.h> #include <net/ping.h> #include <net/udp.h> #include <net/route.h> #include <net/inet_common.h> #include <net/checksum.h> #if IS_ENABLED(CONFIG_IPV6) #include <linux/in6.h> #include <linux/icmpv6.h> #include <net/addrconf.h> #include <net/ipv6.h> #include <net/transp_v6.h> #endif struct ping_table { struct hlist_head hash[PING_HTABLE_SIZE]; spinlock_t lock; }; static struct ping_table ping_table; struct pingv6_ops pingv6_ops; EXPORT_SYMBOL_GPL(pingv6_ops); static u16 ping_port_rover; static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask) { u32 res = (num + net_hash_mix(net)) & mask; pr_debug("hash(%u) = %u\n", num, res); return res; } EXPORT_SYMBOL_GPL(ping_hash); static inline struct hlist_head *ping_hashslot(struct ping_table *table, struct net *net, unsigned int num) { return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)]; } int ping_get_port(struct sock *sk, unsigned short ident) { struct inet_sock *isk, *isk2; struct hlist_head *hlist; struct sock *sk2 = NULL; isk = inet_sk(sk); spin_lock(&ping_table.lock); if (ident == 0) { u32 i; u16 result = ping_port_rover + 1; for (i = 0; i < (1L << 16); i++, result++) { if (!result) result++; /* avoid zero */ hlist = ping_hashslot(&ping_table, sock_net(sk), result); sk_for_each(sk2, hlist) { isk2 = inet_sk(sk2); if (isk2->inet_num == result) goto next_port; } /* found */ ping_port_rover = ident = result; break; next_port: ; } if (i >= (1L << 16)) goto fail; } else { hlist = ping_hashslot(&ping_table, sock_net(sk), ident); sk_for_each(sk2, hlist) { isk2 = inet_sk(sk2); /* BUG? Why is this reuse and not reuseaddr? ping.c * doesn't turn off SO_REUSEADDR, and it doesn't expect * that other ping processes can steal its packets. */ if ((isk2->inet_num == ident) && (sk2 != sk) && (!sk2->sk_reuse || !sk->sk_reuse)) goto fail; } } pr_debug("found port/ident = %d\n", ident); isk->inet_num = ident; if (sk_unhashed(sk)) { pr_debug("was not hashed\n"); sk_add_node_rcu(sk, hlist); sock_set_flag(sk, SOCK_RCU_FREE); sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); } spin_unlock(&ping_table.lock); return 0; fail: spin_unlock(&ping_table.lock); return -EADDRINUSE; } EXPORT_SYMBOL_GPL(ping_get_port); int ping_hash(struct sock *sk) { pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num); BUG(); /* "Please do not press this button again." */ return 0; } void ping_unhash(struct sock *sk) { struct inet_sock *isk = inet_sk(sk); pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num); spin_lock(&ping_table.lock); if (sk_del_node_init_rcu(sk)) { isk->inet_num = 0; isk->inet_sport = 0; sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); } spin_unlock(&ping_table.lock); } EXPORT_SYMBOL_GPL(ping_unhash); /* Called under rcu_read_lock() */ static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident) { struct hlist_head *hslot = ping_hashslot(&ping_table, net, ident); struct sock *sk = NULL; struct inet_sock *isk; int dif, sdif; if (skb->protocol == htons(ETH_P_IP)) { dif = inet_iif(skb); sdif = inet_sdif(skb); pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n", (int)ident, &ip_hdr(skb)->daddr, dif); #if IS_ENABLED(CONFIG_IPV6) } else if (skb->protocol == htons(ETH_P_IPV6)) { dif = inet6_iif(skb); sdif = inet6_sdif(skb); pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n", (int)ident, &ipv6_hdr(skb)->daddr, dif); #endif } else { return NULL; } sk_for_each_rcu(sk, hslot) { isk = inet_sk(sk); pr_debug("iterate\n"); if (isk->inet_num != ident) continue; if (skb->protocol == htons(ETH_P_IP) && sk->sk_family == AF_INET) { pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk, (int) isk->inet_num, &isk->inet_rcv_saddr, sk->sk_bound_dev_if); if (isk->inet_rcv_saddr && isk->inet_rcv_saddr != ip_hdr(skb)->daddr) continue; #if IS_ENABLED(CONFIG_IPV6) } else if (skb->protocol == htons(ETH_P_IPV6) && sk->sk_family == AF_INET6) { pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk, (int) isk->inet_num, &sk->sk_v6_rcv_saddr, sk->sk_bound_dev_if); if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) && !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, &ipv6_hdr(skb)->daddr)) continue; #endif } else { continue; } if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif && sk->sk_bound_dev_if != sdif) continue; goto exit; } sk = NULL; exit: return sk; } static void inet_get_ping_group_range_net(struct net *net, kgid_t *low, kgid_t *high) { kgid_t *data = net->ipv4.ping_group_range.range; unsigned int seq; do { seq = read_seqbegin(&net->ipv4.ping_group_range.lock); *low = data[0]; *high = data[1]; } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq)); } int ping_init_sock(struct sock *sk) { struct net *net = sock_net(sk); kgid_t group = current_egid(); struct group_info *group_info; int i; kgid_t low, high; int ret = 0; if (sk->sk_family == AF_INET6) sk->sk_ipv6only = 1; inet_get_ping_group_range_net(net, &low, &high); if (gid_lte(low, group) && gid_lte(group, high)) return 0; group_info = get_current_groups(); for (i = 0; i < group_info->ngroups; i++) { kgid_t gid = group_info->gid[i]; if (gid_lte(low, gid) && gid_lte(gid, high)) goto out_release_group; } ret = -EACCES; out_release_group: put_group_info(group_info); return ret; } EXPORT_SYMBOL_GPL(ping_init_sock); void ping_close(struct sock *sk, long timeout) { pr_debug("ping_close(sk=%p,sk->num=%u)\n", inet_sk(sk), inet_sk(sk)->inet_num); pr_debug("isk->refcnt = %d\n", refcount_read(&sk->sk_refcnt)); sk_common_release(sk); } EXPORT_SYMBOL_GPL(ping_close); static int ping_pre_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { /* This check is replicated from __ip4_datagram_connect() and * intended to prevent BPF program called below from accessing bytes * that are out of the bound specified by user in addr_len. */ if (addr_len < sizeof(struct sockaddr_in)) return -EINVAL; return BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr); } /* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */ static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk, struct sockaddr *uaddr, int addr_len) { struct net *net = sock_net(sk); if (sk->sk_family == AF_INET) { struct sockaddr_in *addr = (struct sockaddr_in *) uaddr; u32 tb_id = RT_TABLE_LOCAL; int chk_addr_ret; if (addr_len < sizeof(*addr)) return -EINVAL; if (addr->sin_family != AF_INET && !(addr->sin_family == AF_UNSPEC && addr->sin_addr.s_addr == htonl(INADDR_ANY))) return -EAFNOSUPPORT; pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n", sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port)); if (addr->sin_addr.s_addr == htonl(INADDR_ANY)) return 0; tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id; chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id); if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST || (chk_addr_ret != RTN_LOCAL && !inet_can_nonlocal_bind(net, isk))) return -EADDRNOTAVAIL; #if IS_ENABLED(CONFIG_IPV6) } else if (sk->sk_family == AF_INET6) { struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr; int addr_type, scoped, has_addr; struct net_device *dev = NULL; if (addr_len < sizeof(*addr)) return -EINVAL; if (addr->sin6_family != AF_INET6) return -EAFNOSUPPORT; pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n", sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port)); addr_type = ipv6_addr_type(&addr->sin6_addr); scoped = __ipv6_addr_needs_scope_id(addr_type); if ((addr_type != IPV6_ADDR_ANY && !(addr_type & IPV6_ADDR_UNICAST)) || (scoped && !addr->sin6_scope_id)) return -EINVAL; rcu_read_lock(); if (addr->sin6_scope_id) { dev = dev_get_by_index_rcu(net, addr->sin6_scope_id); if (!dev) { rcu_read_unlock(); return -ENODEV; } } if (!dev && sk->sk_bound_dev_if) { dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if); if (!dev) { rcu_read_unlock(); return -ENODEV; } } has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev, scoped); rcu_read_unlock(); if (!(ipv6_can_nonlocal_bind(net, isk) || has_addr || addr_type == IPV6_ADDR_ANY)) return -EADDRNOTAVAIL; if (scoped) sk->sk_bound_dev_if = addr->sin6_scope_id; #endif } else { return -EAFNOSUPPORT; } return 0; } static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr) { if (saddr->sa_family == AF_INET) { struct inet_sock *isk = inet_sk(sk); struct sockaddr_in *addr = (struct sockaddr_in *) saddr; isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr; #if IS_ENABLED(CONFIG_IPV6) } else if (saddr->sa_family == AF_INET6) { struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr; struct ipv6_pinfo *np = inet6_sk(sk); sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr; #endif } } /* * We need our own bind because there are no privileged id's == local ports. * Moreover, we don't allow binding to multi- and broadcast addresses. */ int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) { struct inet_sock *isk = inet_sk(sk); unsigned short snum; int err; int dif = sk->sk_bound_dev_if; err = ping_check_bind_addr(sk, isk, uaddr, addr_len); if (err) return err; lock_sock(sk); err = -EINVAL; if (isk->inet_num != 0) goto out; err = -EADDRINUSE; snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port); if (ping_get_port(sk, snum) != 0) { /* Restore possibly modified sk->sk_bound_dev_if by ping_check_bind_addr(). */ sk->sk_bound_dev_if = dif; goto out; } ping_set_saddr(sk, uaddr); pr_debug("after bind(): num = %hu, dif = %d\n", isk->inet_num, sk->sk_bound_dev_if); err = 0; if (sk->sk_family == AF_INET && isk->inet_rcv_saddr) sk->sk_userlocks |= SOCK_BINDADDR_LOCK; #if IS_ENABLED(CONFIG_IPV6) if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr)) sk->sk_userlocks |= SOCK_BINDADDR_LOCK; #endif if (snum) sk->sk_userlocks |= SOCK_BINDPORT_LOCK; isk->inet_sport = htons(isk->inet_num); isk->inet_daddr = 0; isk->inet_dport = 0; #if IS_ENABLED(CONFIG_IPV6) if (sk->sk_family == AF_INET6) memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr)); #endif sk_dst_reset(sk); out: release_sock(sk); pr_debug("ping_v4_bind -> %d\n", err); return err; } EXPORT_SYMBOL_GPL(ping_bind); /* * Is this a supported type of ICMP message? */ static inline int ping_supported(int family, int type, int code) { return (family == AF_INET && type == ICMP_ECHO && code == 0) || (family == AF_INET && type == ICMP_EXT_ECHO && code == 0) || (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0) || (family == AF_INET6 && type == ICMPV6_EXT_ECHO_REQUEST && code == 0); } /* * This routine is called by the ICMP module when it gets some * sort of error condition. */ void ping_err(struct sk_buff *skb, int offset, u32 info) { int family; struct icmphdr *icmph; struct inet_sock *inet_sock; int type; int code; struct net *net = dev_net(skb->dev); struct sock *sk; int harderr; int err; if (skb->protocol == htons(ETH_P_IP)) { family = AF_INET; type = icmp_hdr(skb)->type; code = icmp_hdr(skb)->code; icmph = (struct icmphdr *)(skb->data + offset); } else if (skb->protocol == htons(ETH_P_IPV6)) { family = AF_INET6; type = icmp6_hdr(skb)->icmp6_type; code = icmp6_hdr(skb)->icmp6_code; icmph = (struct icmphdr *) (skb->data + offset); } else { BUG(); } /* We assume the packet has already been checked by icmp_unreach */ if (!ping_supported(family, icmph->type, icmph->code)) return; pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n", skb->protocol, type, code, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence)); sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id)); if (!sk) { pr_debug("no socket, dropping\n"); return; /* No socket for error */ } pr_debug("err on socket %p\n", sk); err = 0; harderr = 0; inet_sock = inet_sk(sk); if (skb->protocol == htons(ETH_P_IP)) { switch (type) { default: case ICMP_TIME_EXCEEDED: err = EHOSTUNREACH; break; case ICMP_SOURCE_QUENCH: /* This is not a real error but ping wants to see it. * Report it with some fake errno. */ err = EREMOTEIO; break; case ICMP_PARAMETERPROB: err = EPROTO; harderr = 1; break; case ICMP_DEST_UNREACH: if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */ ipv4_sk_update_pmtu(skb, sk, info); if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) { err = EMSGSIZE; harderr = 1; break; } goto out; } err = EHOSTUNREACH; if (code <= NR_ICMP_UNREACH) { harderr = icmp_err_convert[code].fatal; err = icmp_err_convert[code].errno; } break; case ICMP_REDIRECT: /* See ICMP_SOURCE_QUENCH */ ipv4_sk_redirect(skb, sk); err = EREMOTEIO; break; } #if IS_ENABLED(CONFIG_IPV6) } else if (skb->protocol == htons(ETH_P_IPV6)) { harderr = pingv6_ops.icmpv6_err_convert(type, code, &err); #endif } /* * RFC1122: OK. Passes ICMP errors back to application, as per * 4.1.3.3. */ if ((family == AF_INET && !inet_test_bit(RECVERR, sk)) || (family == AF_INET6 && !inet6_sk(sk)->recverr)) { if (!harderr || sk->sk_state != TCP_ESTABLISHED) goto out; } else { if (family == AF_INET) { ip_icmp_error(sk, skb, err, 0 /* no remote port */, info, (u8 *)icmph); #if IS_ENABLED(CONFIG_IPV6) } else if (family == AF_INET6) { pingv6_ops.ipv6_icmp_error(sk, skb, err, 0, info, (u8 *)icmph); #endif } } sk->sk_err = err; sk_error_report(sk); out: return; } EXPORT_SYMBOL_GPL(ping_err); /* * Copy and checksum an ICMP Echo packet from user space into a buffer * starting from the payload. */ int ping_getfrag(void *from, char *to, int offset, int fraglen, int odd, struct sk_buff *skb) { struct pingfakehdr *pfh = from; if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck, &pfh->msg->msg_iter)) return -EFAULT; #if IS_ENABLED(CONFIG_IPV6) /* For IPv6, checksum each skb as we go along, as expected by * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in * wcheck, it will be finalized in ping_v4_push_pending_frames. */ if (pfh->family == AF_INET6) { skb->csum = csum_block_add(skb->csum, pfh->wcheck, odd); skb->ip_summed = CHECKSUM_NONE; pfh->wcheck = 0; } #endif return 0; } EXPORT_SYMBOL_GPL(ping_getfrag); static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh, struct flowi4 *fl4) { struct sk_buff *skb = skb_peek(&sk->sk_write_queue); if (!skb) return 0; pfh->wcheck = csum_partial((char *)&pfh->icmph, sizeof(struct icmphdr), pfh->wcheck); pfh->icmph.checksum = csum_fold(pfh->wcheck); memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr)); skb->ip_summed = CHECKSUM_NONE; return ip_push_pending_frames(sk, fl4); } int ping_common_sendmsg(int family, struct msghdr *msg, size_t len, void *user_icmph, size_t icmph_len) { u8 type, code; if (len > 0xFFFF) return -EMSGSIZE; /* Must have at least a full ICMP header. */ if (len < icmph_len) return -EINVAL; /* * Check the flags. */ /* Mirror BSD error message compatibility */ if (msg->msg_flags & MSG_OOB) return -EOPNOTSUPP; /* * Fetch the ICMP header provided by the userland. * iovec is modified! The ICMP header is consumed. */ if (memcpy_from_msg(user_icmph, msg, icmph_len)) return -EFAULT; if (family == AF_INET) { type = ((struct icmphdr *) user_icmph)->type; code = ((struct icmphdr *) user_icmph)->code; #if IS_ENABLED(CONFIG_IPV6) } else if (family == AF_INET6) { type = ((struct icmp6hdr *) user_icmph)->icmp6_type; code = ((struct icmp6hdr *) user_icmph)->icmp6_code; #endif } else { BUG(); } if (!ping_supported(family, type, code)) return -EINVAL; return 0; } EXPORT_SYMBOL_GPL(ping_common_sendmsg); static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) { struct net *net = sock_net(sk); struct flowi4 fl4; struct inet_sock *inet = inet_sk(sk); struct ipcm_cookie ipc; struct icmphdr user_icmph; struct pingfakehdr pfh; struct rtable *rt = NULL; struct ip_options_data opt_copy; int free = 0; __be32 saddr, daddr, faddr; u8 tos, scope; int err; pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num); err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph, sizeof(user_icmph)); if (err) return err; /* * Get and verify the address. */ if (msg->msg_name) { DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name); if (msg->msg_namelen < sizeof(*usin)) return -EINVAL; if (usin->sin_family != AF_INET) return -EAFNOSUPPORT; daddr = usin->sin_addr.s_addr; /* no remote port */ } else { if (sk->sk_state != TCP_ESTABLISHED) return -EDESTADDRREQ; daddr = inet->inet_daddr; /* no remote port */ } ipcm_init_sk(&ipc, inet); if (msg->msg_controllen) { err = ip_cmsg_send(sk, msg, &ipc, false); if (unlikely(err)) { kfree(ipc.opt); return err; } if (ipc.opt) free = 1; } if (!ipc.opt) { struct ip_options_rcu *inet_opt; rcu_read_lock(); inet_opt = rcu_dereference(inet->inet_opt); if (inet_opt) { memcpy(&opt_copy, inet_opt, sizeof(*inet_opt) + inet_opt->opt.optlen); ipc.opt = &opt_copy.opt; } rcu_read_unlock(); } saddr = ipc.addr; ipc.addr = faddr = daddr; if (ipc.opt && ipc.opt->opt.srr) { if (!daddr) { err = -EINVAL; goto out_free; } faddr = ipc.opt->opt.faddr; } tos = get_rttos(&ipc, inet); scope = ip_sendmsg_scope(inet, &ipc, msg); if (ipv4_is_multicast(daddr)) { if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif)) ipc.oif = inet->mc_index; if (!saddr) saddr = inet->mc_addr; } else if (!ipc.oif) ipc.oif = inet->uc_index; flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos, scope, sk->sk_protocol, inet_sk_flowi_flags(sk), faddr, saddr, 0, 0, sk->sk_uid); fl4.fl4_icmp_type = user_icmph.type; fl4.fl4_icmp_code = user_icmph.code; security_sk_classify_flow(sk, flowi4_to_flowi_common(&fl4)); rt = ip_route_output_flow(net, &fl4, sk); if (IS_ERR(rt)) { err = PTR_ERR(rt); rt = NULL; if (err == -ENETUNREACH) IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); goto out; } err = -EACCES; if ((rt->rt_flags & RTCF_BROADCAST) && !sock_flag(sk, SOCK_BROADCAST)) goto out; if (msg->msg_flags & MSG_CONFIRM) goto do_confirm; back_from_confirm: if (!ipc.addr) ipc.addr = fl4.daddr; lock_sock(sk); pfh.icmph.type = user_icmph.type; /* already checked */ pfh.icmph.code = user_icmph.code; /* ditto */ pfh.icmph.checksum = 0; pfh.icmph.un.echo.id = inet->inet_sport; pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence; pfh.msg = msg; pfh.wcheck = 0; pfh.family = AF_INET; err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len, sizeof(struct icmphdr), &ipc, &rt, msg->msg_flags); if (err) ip_flush_pending_frames(sk); else err = ping_v4_push_pending_frames(sk, &pfh, &fl4); release_sock(sk); out: ip_rt_put(rt); out_free: if (free) kfree(ipc.opt); if (!err) { icmp_out_count(sock_net(sk), user_icmph.type); return len; } return err; do_confirm: if (msg->msg_flags & MSG_PROBE) dst_confirm_neigh(&rt->dst, &fl4.daddr); if (!(msg->msg_flags & MSG_PROBE) || len) goto back_from_confirm; err = 0; goto out; } int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { struct inet_sock *isk = inet_sk(sk); int family = sk->sk_family; struct sk_buff *skb; int copied, err; pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num); err = -EOPNOTSUPP; if (flags & MSG_OOB) goto out; if (flags & MSG_ERRQUEUE) return inet_recv_error(sk, msg, len, addr_len); skb = skb_recv_datagram(sk, flags, &err); if (!skb) goto out; copied = skb->len; if (copied > len) { msg->msg_flags |= MSG_TRUNC; copied = len; } /* Don't bother checking the checksum */ err = skb_copy_datagram_msg(skb, 0, msg, copied); if (err) goto done; sock_recv_timestamp(msg, sk, skb); /* Copy the address and add cmsg data. */ if (family == AF_INET) { DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); if (sin) { sin->sin_family = AF_INET; sin->sin_port = 0 /* skb->h.uh->source */; sin->sin_addr.s_addr = ip_hdr(skb)->saddr; memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); *addr_len = sizeof(*sin); } if (inet_cmsg_flags(isk)) ip_cmsg_recv(msg, skb); #if IS_ENABLED(CONFIG_IPV6) } else if (family == AF_INET6) { struct ipv6_pinfo *np = inet6_sk(sk); struct ipv6hdr *ip6 = ipv6_hdr(skb); DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); if (sin6) { sin6->sin6_family = AF_INET6; sin6->sin6_port = 0; sin6->sin6_addr = ip6->saddr; sin6->sin6_flowinfo = 0; if (np->sndflow) sin6->sin6_flowinfo = ip6_flowinfo(ip6); sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr, inet6_iif(skb)); *addr_len = sizeof(*sin6); } if (inet6_sk(sk)->rxopt.all) pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb); if (skb->protocol == htons(ETH_P_IPV6) && inet6_sk(sk)->rxopt.all) pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb); else if (skb->protocol == htons(ETH_P_IP) && inet_cmsg_flags(isk)) ip_cmsg_recv(msg, skb); #endif } else { BUG(); } err = copied; done: skb_free_datagram(sk, skb); out: pr_debug("ping_recvmsg -> %d\n", err); return err; } EXPORT_SYMBOL_GPL(ping_recvmsg); static enum skb_drop_reason __ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) { enum skb_drop_reason reason; pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n", inet_sk(sk), inet_sk(sk)->inet_num, skb); if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0) { kfree_skb_reason(skb, reason); pr_debug("ping_queue_rcv_skb -> failed\n"); return reason; } return SKB_NOT_DROPPED_YET; } int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) { return __ping_queue_rcv_skb(sk, skb) ? -1 : 0; } EXPORT_SYMBOL_GPL(ping_queue_rcv_skb); /* * All we need to do is get the socket. */ enum skb_drop_reason ping_rcv(struct sk_buff *skb) { enum skb_drop_reason reason = SKB_DROP_REASON_NO_SOCKET; struct sock *sk; struct net *net = dev_net(skb->dev); struct icmphdr *icmph = icmp_hdr(skb); /* We assume the packet has already been checked by icmp_rcv */ pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n", skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence)); /* Push ICMP header back */ skb_push(skb, skb->data - (u8 *)icmph); sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id)); if (sk) { struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); pr_debug("rcv on socket %p\n", sk); if (skb2) reason = __ping_queue_rcv_skb(sk, skb2); else reason = SKB_DROP_REASON_NOMEM; } if (reason) pr_debug("no socket, dropping\n"); return reason; } EXPORT_SYMBOL_GPL(ping_rcv); struct proto ping_prot = { .name = "PING", .owner = THIS_MODULE, .init = ping_init_sock, .close = ping_close, .pre_connect = ping_pre_connect, .connect = ip4_datagram_connect, .disconnect = __udp_disconnect, .setsockopt = ip_setsockopt, .getsockopt = ip_getsockopt, .sendmsg = ping_v4_sendmsg, .recvmsg = ping_recvmsg, .bind = ping_bind, .backlog_rcv = ping_queue_rcv_skb, .release_cb = ip4_datagram_release_cb, .hash = ping_hash, .unhash = ping_unhash, .get_port = ping_get_port, .put_port = ping_unhash, .obj_size = sizeof(struct inet_sock), }; EXPORT_SYMBOL(ping_prot); #ifdef CONFIG_PROC_FS static struct sock *ping_get_first(struct seq_file *seq, int start) { struct sock *sk; struct ping_iter_state *state = seq->private; struct net *net = seq_file_net(seq); for (state->bucket = start; state->bucket < PING_HTABLE_SIZE; ++state->bucket) { struct hlist_head *hslot; hslot = &ping_table.hash[state->bucket]; if (hlist_empty(hslot)) continue; sk_for_each(sk, hslot) { if (net_eq(sock_net(sk), net) && sk->sk_family == state->family) goto found; } } sk = NULL; found: return sk; } static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk) { struct ping_iter_state *state = seq->private; struct net *net = seq_file_net(seq); do { sk = sk_next(sk); } while (sk && (!net_eq(sock_net(sk), net))); if (!sk) return ping_get_first(seq, state->bucket + 1); return sk; } static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos) { struct sock *sk = ping_get_first(seq, 0); if (sk) while (pos && (sk = ping_get_next(seq, sk)) != NULL) --pos; return pos ? NULL : sk; } void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family) __acquires(ping_table.lock) { struct ping_iter_state *state = seq->private; state->bucket = 0; state->family = family; spin_lock(&ping_table.lock); return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN; } EXPORT_SYMBOL_GPL(ping_seq_start); static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos) { return ping_seq_start(seq, pos, AF_INET); } void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct sock *sk; if (v == SEQ_START_TOKEN) sk = ping_get_idx(seq, 0); else sk = ping_get_next(seq, v); ++*pos; return sk; } EXPORT_SYMBOL_GPL(ping_seq_next); void ping_seq_stop(struct seq_file *seq, void *v) __releases(ping_table.lock) { spin_unlock(&ping_table.lock); } EXPORT_SYMBOL_GPL(ping_seq_stop); static void ping_v4_format_sock(struct sock *sp, struct seq_file *f, int bucket) { struct inet_sock *inet = inet_sk(sp); __be32 dest = inet->inet_daddr; __be32 src = inet->inet_rcv_saddr; __u16 destp = ntohs(inet->inet_dport); __u16 srcp = ntohs(inet->inet_sport); seq_printf(f, "%5d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u", bucket, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), 0, 0L, 0, from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)), 0, sock_i_ino(sp), refcount_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); } static int ping_v4_seq_show(struct seq_file *seq, void *v) { seq_setwidth(seq, 127); if (v == SEQ_START_TOKEN) seq_puts(seq, " sl local_address rem_address st tx_queue " "rx_queue tr tm->when retrnsmt uid timeout " "inode ref pointer drops"); else { struct ping_iter_state *state = seq->private; ping_v4_format_sock(v, seq, state->bucket); } seq_pad(seq, '\n'); return 0; } static const struct seq_operations ping_v4_seq_ops = { .start = ping_v4_seq_start, .show = ping_v4_seq_show, .next = ping_seq_next, .stop = ping_seq_stop, }; static int __net_init ping_v4_proc_init_net(struct net *net) { if (!proc_create_net("icmp", 0444, net->proc_net, &ping_v4_seq_ops, sizeof(struct ping_iter_state))) return -ENOMEM; return 0; } static void __net_exit ping_v4_proc_exit_net(struct net *net) { remove_proc_entry("icmp", net->proc_net); } static struct pernet_operations ping_v4_net_ops = { .init = ping_v4_proc_init_net, .exit = ping_v4_proc_exit_net, }; int __init ping_proc_init(void) { return register_pernet_subsys(&ping_v4_net_ops); } void ping_proc_exit(void) { unregister_pernet_subsys(&ping_v4_net_ops); } #endif void __init ping_init(void) { int i; for (i = 0; i < PING_HTABLE_SIZE; i++) INIT_HLIST_HEAD(&ping_table.hash[i]); spin_lock_init(&ping_table.lock); }
linux-master
net/ipv4/ping.c
// SPDX-License-Identifier: GPL-2.0-only /* * Sally Floyd's High Speed TCP (RFC 3649) congestion control * * See https://www.icir.org/floyd/hstcp.html * * John Heffner <[email protected]> */ #include <linux/module.h> #include <net/tcp.h> /* From AIMD tables from RFC 3649 appendix B, * with fixed-point MD scaled <<8. */ static const struct hstcp_aimd_val { unsigned int cwnd; unsigned int md; } hstcp_aimd_vals[] = { { 38, 128, /* 0.50 */ }, { 118, 112, /* 0.44 */ }, { 221, 104, /* 0.41 */ }, { 347, 98, /* 0.38 */ }, { 495, 93, /* 0.37 */ }, { 663, 89, /* 0.35 */ }, { 851, 86, /* 0.34 */ }, { 1058, 83, /* 0.33 */ }, { 1284, 81, /* 0.32 */ }, { 1529, 78, /* 0.31 */ }, { 1793, 76, /* 0.30 */ }, { 2076, 74, /* 0.29 */ }, { 2378, 72, /* 0.28 */ }, { 2699, 71, /* 0.28 */ }, { 3039, 69, /* 0.27 */ }, { 3399, 68, /* 0.27 */ }, { 3778, 66, /* 0.26 */ }, { 4177, 65, /* 0.26 */ }, { 4596, 64, /* 0.25 */ }, { 5036, 62, /* 0.25 */ }, { 5497, 61, /* 0.24 */ }, { 5979, 60, /* 0.24 */ }, { 6483, 59, /* 0.23 */ }, { 7009, 58, /* 0.23 */ }, { 7558, 57, /* 0.22 */ }, { 8130, 56, /* 0.22 */ }, { 8726, 55, /* 0.22 */ }, { 9346, 54, /* 0.21 */ }, { 9991, 53, /* 0.21 */ }, { 10661, 52, /* 0.21 */ }, { 11358, 52, /* 0.20 */ }, { 12082, 51, /* 0.20 */ }, { 12834, 50, /* 0.20 */ }, { 13614, 49, /* 0.19 */ }, { 14424, 48, /* 0.19 */ }, { 15265, 48, /* 0.19 */ }, { 16137, 47, /* 0.19 */ }, { 17042, 46, /* 0.18 */ }, { 17981, 45, /* 0.18 */ }, { 18955, 45, /* 0.18 */ }, { 19965, 44, /* 0.17 */ }, { 21013, 43, /* 0.17 */ }, { 22101, 43, /* 0.17 */ }, { 23230, 42, /* 0.17 */ }, { 24402, 41, /* 0.16 */ }, { 25618, 41, /* 0.16 */ }, { 26881, 40, /* 0.16 */ }, { 28193, 39, /* 0.16 */ }, { 29557, 39, /* 0.15 */ }, { 30975, 38, /* 0.15 */ }, { 32450, 38, /* 0.15 */ }, { 33986, 37, /* 0.15 */ }, { 35586, 36, /* 0.14 */ }, { 37253, 36, /* 0.14 */ }, { 38992, 35, /* 0.14 */ }, { 40808, 35, /* 0.14 */ }, { 42707, 34, /* 0.13 */ }, { 44694, 33, /* 0.13 */ }, { 46776, 33, /* 0.13 */ }, { 48961, 32, /* 0.13 */ }, { 51258, 32, /* 0.13 */ }, { 53677, 31, /* 0.12 */ }, { 56230, 30, /* 0.12 */ }, { 58932, 30, /* 0.12 */ }, { 61799, 29, /* 0.12 */ }, { 64851, 28, /* 0.11 */ }, { 68113, 28, /* 0.11 */ }, { 71617, 27, /* 0.11 */ }, { 75401, 26, /* 0.10 */ }, { 79517, 26, /* 0.10 */ }, { 84035, 25, /* 0.10 */ }, { 89053, 24, /* 0.10 */ }, }; #define HSTCP_AIMD_MAX ARRAY_SIZE(hstcp_aimd_vals) struct hstcp { u32 ai; }; static void hstcp_init(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct hstcp *ca = inet_csk_ca(sk); ca->ai = 0; /* Ensure the MD arithmetic works. This is somewhat pedantic, * since I don't think we will see a cwnd this large. :) */ tp->snd_cwnd_clamp = min_t(u32, tp->snd_cwnd_clamp, 0xffffffff/128); } static void hstcp_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct hstcp *ca = inet_csk_ca(sk); if (!tcp_is_cwnd_limited(sk)) return; if (tcp_in_slow_start(tp)) tcp_slow_start(tp, acked); else { /* Update AIMD parameters. * * We want to guarantee that: * hstcp_aimd_vals[ca->ai-1].cwnd < * snd_cwnd <= * hstcp_aimd_vals[ca->ai].cwnd */ if (tcp_snd_cwnd(tp) > hstcp_aimd_vals[ca->ai].cwnd) { while (tcp_snd_cwnd(tp) > hstcp_aimd_vals[ca->ai].cwnd && ca->ai < HSTCP_AIMD_MAX - 1) ca->ai++; } else if (ca->ai && tcp_snd_cwnd(tp) <= hstcp_aimd_vals[ca->ai-1].cwnd) { while (ca->ai && tcp_snd_cwnd(tp) <= hstcp_aimd_vals[ca->ai-1].cwnd) ca->ai--; } /* Do additive increase */ if (tcp_snd_cwnd(tp) < tp->snd_cwnd_clamp) { /* cwnd = cwnd + a(w) / cwnd */ tp->snd_cwnd_cnt += ca->ai + 1; if (tp->snd_cwnd_cnt >= tcp_snd_cwnd(tp)) { tp->snd_cwnd_cnt -= tcp_snd_cwnd(tp); tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) + 1); } } } } static u32 hstcp_ssthresh(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct hstcp *ca = inet_csk_ca(sk); /* Do multiplicative decrease */ return max(tcp_snd_cwnd(tp) - ((tcp_snd_cwnd(tp) * hstcp_aimd_vals[ca->ai].md) >> 8), 2U); } static struct tcp_congestion_ops tcp_highspeed __read_mostly = { .init = hstcp_init, .ssthresh = hstcp_ssthresh, .undo_cwnd = tcp_reno_undo_cwnd, .cong_avoid = hstcp_cong_avoid, .owner = THIS_MODULE, .name = "highspeed" }; static int __init hstcp_register(void) { BUILD_BUG_ON(sizeof(struct hstcp) > ICSK_CA_PRIV_SIZE); return tcp_register_congestion_control(&tcp_highspeed); } static void __exit hstcp_unregister(void) { tcp_unregister_congestion_control(&tcp_highspeed); } module_init(hstcp_register); module_exit(hstcp_unregister); MODULE_AUTHOR("John Heffner"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("High Speed TCP");
linux-master
net/ipv4/tcp_highspeed.c
// SPDX-License-Identifier: GPL-2.0-only /* * TCP HYBLA * * TCP-HYBLA Congestion control algorithm, based on: * C.Caini, R.Firrincieli, "TCP-Hybla: A TCP Enhancement * for Heterogeneous Networks", * International Journal on satellite Communications, * September 2004 * Daniele Lacamera * root at danielinux.net */ #include <linux/module.h> #include <net/tcp.h> /* Tcp Hybla structure. */ struct hybla { bool hybla_en; u32 snd_cwnd_cents; /* Keeps increment values when it is <1, <<7 */ u32 rho; /* Rho parameter, integer part */ u32 rho2; /* Rho * Rho, integer part */ u32 rho_3ls; /* Rho parameter, <<3 */ u32 rho2_7ls; /* Rho^2, <<7 */ u32 minrtt_us; /* Minimum smoothed round trip time value seen */ }; /* Hybla reference round trip time (default= 1/40 sec = 25 ms), in ms */ static int rtt0 = 25; module_param(rtt0, int, 0644); MODULE_PARM_DESC(rtt0, "reference rout trip time (ms)"); /* This is called to refresh values for hybla parameters */ static inline void hybla_recalc_param (struct sock *sk) { struct hybla *ca = inet_csk_ca(sk); ca->rho_3ls = max_t(u32, tcp_sk(sk)->srtt_us / (rtt0 * USEC_PER_MSEC), 8U); ca->rho = ca->rho_3ls >> 3; ca->rho2_7ls = (ca->rho_3ls * ca->rho_3ls) << 1; ca->rho2 = ca->rho2_7ls >> 7; } static void hybla_init(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct hybla *ca = inet_csk_ca(sk); ca->rho = 0; ca->rho2 = 0; ca->rho_3ls = 0; ca->rho2_7ls = 0; ca->snd_cwnd_cents = 0; ca->hybla_en = true; tcp_snd_cwnd_set(tp, 2); tp->snd_cwnd_clamp = 65535; /* 1st Rho measurement based on initial srtt */ hybla_recalc_param(sk); /* set minimum rtt as this is the 1st ever seen */ ca->minrtt_us = tp->srtt_us; tcp_snd_cwnd_set(tp, ca->rho); } static void hybla_state(struct sock *sk, u8 ca_state) { struct hybla *ca = inet_csk_ca(sk); ca->hybla_en = (ca_state == TCP_CA_Open); } static inline u32 hybla_fraction(u32 odds) { static const u32 fractions[] = { 128, 139, 152, 165, 181, 197, 215, 234, }; return (odds < ARRAY_SIZE(fractions)) ? fractions[odds] : 128; } /* TCP Hybla main routine. * This is the algorithm behavior: * o Recalc Hybla parameters if min_rtt has changed * o Give cwnd a new value based on the model proposed * o remember increments <1 */ static void hybla_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct hybla *ca = inet_csk_ca(sk); u32 increment, odd, rho_fractions; int is_slowstart = 0; /* Recalculate rho only if this srtt is the lowest */ if (tp->srtt_us < ca->minrtt_us) { hybla_recalc_param(sk); ca->minrtt_us = tp->srtt_us; } if (!tcp_is_cwnd_limited(sk)) return; if (!ca->hybla_en) { tcp_reno_cong_avoid(sk, ack, acked); return; } if (ca->rho == 0) hybla_recalc_param(sk); rho_fractions = ca->rho_3ls - (ca->rho << 3); if (tcp_in_slow_start(tp)) { /* * slow start * INC = 2^RHO - 1 * This is done by splitting the rho parameter * into 2 parts: an integer part and a fraction part. * Inrement<<7 is estimated by doing: * [2^(int+fract)]<<7 * that is equal to: * (2^int) * [(2^fract) <<7] * 2^int is straightly computed as 1<<int, * while we will use hybla_slowstart_fraction_increment() to * calculate 2^fract in a <<7 value. */ is_slowstart = 1; increment = ((1 << min(ca->rho, 16U)) * hybla_fraction(rho_fractions)) - 128; } else { /* * congestion avoidance * INC = RHO^2 / W * as long as increment is estimated as (rho<<7)/window * it already is <<7 and we can easily count its fractions. */ increment = ca->rho2_7ls / tcp_snd_cwnd(tp); if (increment < 128) tp->snd_cwnd_cnt++; } odd = increment % 128; tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) + (increment >> 7)); ca->snd_cwnd_cents += odd; /* check when fractions goes >=128 and increase cwnd by 1. */ while (ca->snd_cwnd_cents >= 128) { tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) + 1); ca->snd_cwnd_cents -= 128; tp->snd_cwnd_cnt = 0; } /* check when cwnd has not been incremented for a while */ if (increment == 0 && odd == 0 && tp->snd_cwnd_cnt >= tcp_snd_cwnd(tp)) { tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) + 1); tp->snd_cwnd_cnt = 0; } /* clamp down slowstart cwnd to ssthresh value. */ if (is_slowstart) tcp_snd_cwnd_set(tp, min(tcp_snd_cwnd(tp), tp->snd_ssthresh)); tcp_snd_cwnd_set(tp, min(tcp_snd_cwnd(tp), tp->snd_cwnd_clamp)); } static struct tcp_congestion_ops tcp_hybla __read_mostly = { .init = hybla_init, .ssthresh = tcp_reno_ssthresh, .undo_cwnd = tcp_reno_undo_cwnd, .cong_avoid = hybla_cong_avoid, .set_state = hybla_state, .owner = THIS_MODULE, .name = "hybla" }; static int __init hybla_register(void) { BUILD_BUG_ON(sizeof(struct hybla) > ICSK_CA_PRIV_SIZE); return tcp_register_congestion_control(&tcp_hybla); } static void __exit hybla_unregister(void) { tcp_unregister_congestion_control(&tcp_hybla); } module_init(hybla_register); module_exit(hybla_unregister); MODULE_AUTHOR("Daniele Lacamera"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("TCP Hybla");
linux-master
net/ipv4/tcp_hybla.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * The User Datagram Protocol (UDP). * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * Arnt Gulbrandsen, <[email protected]> * Alan Cox, <[email protected]> * Hirokazu Takahashi, <[email protected]> * * Fixes: * Alan Cox : verify_area() calls * Alan Cox : stopped close while in use off icmp * messages. Not a fix but a botch that * for udp at least is 'valid'. * Alan Cox : Fixed icmp handling properly * Alan Cox : Correct error for oversized datagrams * Alan Cox : Tidied select() semantics. * Alan Cox : udp_err() fixed properly, also now * select and read wake correctly on errors * Alan Cox : udp_send verify_area moved to avoid mem leak * Alan Cox : UDP can count its memory * Alan Cox : send to an unknown connection causes * an ECONNREFUSED off the icmp, but * does NOT close. * Alan Cox : Switched to new sk_buff handlers. No more backlog! * Alan Cox : Using generic datagram code. Even smaller and the PEEK * bug no longer crashes it. * Fred Van Kempen : Net2e support for sk->broadcast. * Alan Cox : Uses skb_free_datagram * Alan Cox : Added get/set sockopt support. * Alan Cox : Broadcasting without option set returns EACCES. * Alan Cox : No wakeup calls. Instead we now use the callbacks. * Alan Cox : Use ip_tos and ip_ttl * Alan Cox : SNMP Mibs * Alan Cox : MSG_DONTROUTE, and 0.0.0.0 support. * Matt Dillon : UDP length checks. * Alan Cox : Smarter af_inet used properly. * Alan Cox : Use new kernel side addressing. * Alan Cox : Incorrect return on truncated datagram receive. * Arnt Gulbrandsen : New udp_send and stuff * Alan Cox : Cache last socket * Alan Cox : Route cache * Jon Peatfield : Minor efficiency fix to sendto(). * Mike Shaver : RFC1122 checks. * Alan Cox : Nonblocking error fix. * Willy Konynenberg : Transparent proxying support. * Mike McLagan : Routing by source * David S. Miller : New socket lookup architecture. * Last socket cache retained as it * does have a high hit rate. * Olaf Kirch : Don't linearise iovec on sendmsg. * Andi Kleen : Some cleanups, cache destination entry * for connect. * Vitaly E. Lavrov : Transparent proxy revived after year coma. * Melvin Smith : Check msg_name not msg_namelen in sendto(), * return ENOTCONN for unconnected sockets (POSIX) * Janos Farkas : don't deliver multi/broadcasts to a different * bound-to-device socket * Hirokazu Takahashi : HW checksumming for outgoing UDP * datagrams. * Hirokazu Takahashi : sendfile() on UDP works now. * Arnaldo C. Melo : convert /proc/net/udp to seq_file * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which * Alexey Kuznetsov: allow both IPv4 and IPv6 sockets to bind * a single port at the same time. * Derek Atkins <[email protected]>: Add Encapulation Support * James Chapman : Add L2TP encapsulation type. */ #define pr_fmt(fmt) "UDP: " fmt #include <linux/bpf-cgroup.h> #include <linux/uaccess.h> #include <asm/ioctls.h> #include <linux/memblock.h> #include <linux/highmem.h> #include <linux/types.h> #include <linux/fcntl.h> #include <linux/module.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/igmp.h> #include <linux/inetdevice.h> #include <linux/in.h> #include <linux/errno.h> #include <linux/timer.h> #include <linux/mm.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <linux/slab.h> #include <net/tcp_states.h> #include <linux/skbuff.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <net/net_namespace.h> #include <net/icmp.h> #include <net/inet_hashtables.h> #include <net/ip_tunnels.h> #include <net/route.h> #include <net/checksum.h> #include <net/gso.h> #include <net/xfrm.h> #include <trace/events/udp.h> #include <linux/static_key.h> #include <linux/btf_ids.h> #include <trace/events/skb.h> #include <net/busy_poll.h> #include "udp_impl.h" #include <net/sock_reuseport.h> #include <net/addrconf.h> #include <net/udp_tunnel.h> #include <net/gro.h> #if IS_ENABLED(CONFIG_IPV6) #include <net/ipv6_stubs.h> #endif struct udp_table udp_table __read_mostly; EXPORT_SYMBOL(udp_table); long sysctl_udp_mem[3] __read_mostly; EXPORT_SYMBOL(sysctl_udp_mem); atomic_long_t udp_memory_allocated ____cacheline_aligned_in_smp; EXPORT_SYMBOL(udp_memory_allocated); DEFINE_PER_CPU(int, udp_memory_per_cpu_fw_alloc); EXPORT_PER_CPU_SYMBOL_GPL(udp_memory_per_cpu_fw_alloc); #define MAX_UDP_PORTS 65536 #define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN_PERNET) static struct udp_table *udp_get_table_prot(struct sock *sk) { return sk->sk_prot->h.udp_table ? : sock_net(sk)->ipv4.udp_table; } static int udp_lib_lport_inuse(struct net *net, __u16 num, const struct udp_hslot *hslot, unsigned long *bitmap, struct sock *sk, unsigned int log) { struct sock *sk2; kuid_t uid = sock_i_uid(sk); sk_for_each(sk2, &hslot->head) { if (net_eq(sock_net(sk2), net) && sk2 != sk && (bitmap || udp_sk(sk2)->udp_port_hash == num) && (!sk2->sk_reuse || !sk->sk_reuse) && (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && inet_rcv_saddr_equal(sk, sk2, true)) { if (sk2->sk_reuseport && sk->sk_reuseport && !rcu_access_pointer(sk->sk_reuseport_cb) && uid_eq(uid, sock_i_uid(sk2))) { if (!bitmap) return 0; } else { if (!bitmap) return 1; __set_bit(udp_sk(sk2)->udp_port_hash >> log, bitmap); } } } return 0; } /* * Note: we still hold spinlock of primary hash chain, so no other writer * can insert/delete a socket with local_port == num */ static int udp_lib_lport_inuse2(struct net *net, __u16 num, struct udp_hslot *hslot2, struct sock *sk) { struct sock *sk2; kuid_t uid = sock_i_uid(sk); int res = 0; spin_lock(&hslot2->lock); udp_portaddr_for_each_entry(sk2, &hslot2->head) { if (net_eq(sock_net(sk2), net) && sk2 != sk && (udp_sk(sk2)->udp_port_hash == num) && (!sk2->sk_reuse || !sk->sk_reuse) && (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && inet_rcv_saddr_equal(sk, sk2, true)) { if (sk2->sk_reuseport && sk->sk_reuseport && !rcu_access_pointer(sk->sk_reuseport_cb) && uid_eq(uid, sock_i_uid(sk2))) { res = 0; } else { res = 1; } break; } } spin_unlock(&hslot2->lock); return res; } static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot) { struct net *net = sock_net(sk); kuid_t uid = sock_i_uid(sk); struct sock *sk2; sk_for_each(sk2, &hslot->head) { if (net_eq(sock_net(sk2), net) && sk2 != sk && sk2->sk_family == sk->sk_family && ipv6_only_sock(sk2) == ipv6_only_sock(sk) && (udp_sk(sk2)->udp_port_hash == udp_sk(sk)->udp_port_hash) && (sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) && inet_rcv_saddr_equal(sk, sk2, false)) { return reuseport_add_sock(sk, sk2, inet_rcv_saddr_any(sk)); } } return reuseport_alloc(sk, inet_rcv_saddr_any(sk)); } /** * udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6 * * @sk: socket struct in question * @snum: port number to look up * @hash2_nulladdr: AF-dependent hash value in secondary hash chains, * with NULL address */ int udp_lib_get_port(struct sock *sk, unsigned short snum, unsigned int hash2_nulladdr) { struct udp_table *udptable = udp_get_table_prot(sk); struct udp_hslot *hslot, *hslot2; struct net *net = sock_net(sk); int error = -EADDRINUSE; if (!snum) { DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN); unsigned short first, last; int low, high, remaining; unsigned int rand; inet_sk_get_local_port_range(sk, &low, &high); remaining = (high - low) + 1; rand = get_random_u32(); first = reciprocal_scale(rand, remaining) + low; /* * force rand to be an odd multiple of UDP_HTABLE_SIZE */ rand = (rand | 1) * (udptable->mask + 1); last = first + udptable->mask + 1; do { hslot = udp_hashslot(udptable, net, first); bitmap_zero(bitmap, PORTS_PER_CHAIN); spin_lock_bh(&hslot->lock); udp_lib_lport_inuse(net, snum, hslot, bitmap, sk, udptable->log); snum = first; /* * Iterate on all possible values of snum for this hash. * Using steps of an odd multiple of UDP_HTABLE_SIZE * give us randomization and full range coverage. */ do { if (low <= snum && snum <= high && !test_bit(snum >> udptable->log, bitmap) && !inet_is_local_reserved_port(net, snum)) goto found; snum += rand; } while (snum != first); spin_unlock_bh(&hslot->lock); cond_resched(); } while (++first != last); goto fail; } else { hslot = udp_hashslot(udptable, net, snum); spin_lock_bh(&hslot->lock); if (hslot->count > 10) { int exist; unsigned int slot2 = udp_sk(sk)->udp_portaddr_hash ^ snum; slot2 &= udptable->mask; hash2_nulladdr &= udptable->mask; hslot2 = udp_hashslot2(udptable, slot2); if (hslot->count < hslot2->count) goto scan_primary_hash; exist = udp_lib_lport_inuse2(net, snum, hslot2, sk); if (!exist && (hash2_nulladdr != slot2)) { hslot2 = udp_hashslot2(udptable, hash2_nulladdr); exist = udp_lib_lport_inuse2(net, snum, hslot2, sk); } if (exist) goto fail_unlock; else goto found; } scan_primary_hash: if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk, 0)) goto fail_unlock; } found: inet_sk(sk)->inet_num = snum; udp_sk(sk)->udp_port_hash = snum; udp_sk(sk)->udp_portaddr_hash ^= snum; if (sk_unhashed(sk)) { if (sk->sk_reuseport && udp_reuseport_add_sock(sk, hslot)) { inet_sk(sk)->inet_num = 0; udp_sk(sk)->udp_port_hash = 0; udp_sk(sk)->udp_portaddr_hash ^= snum; goto fail_unlock; } sk_add_node_rcu(sk, &hslot->head); hslot->count++; sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash); spin_lock(&hslot2->lock); if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && sk->sk_family == AF_INET6) hlist_add_tail_rcu(&udp_sk(sk)->udp_portaddr_node, &hslot2->head); else hlist_add_head_rcu(&udp_sk(sk)->udp_portaddr_node, &hslot2->head); hslot2->count++; spin_unlock(&hslot2->lock); } sock_set_flag(sk, SOCK_RCU_FREE); error = 0; fail_unlock: spin_unlock_bh(&hslot->lock); fail: return error; } EXPORT_SYMBOL(udp_lib_get_port); int udp_v4_get_port(struct sock *sk, unsigned short snum) { unsigned int hash2_nulladdr = ipv4_portaddr_hash(sock_net(sk), htonl(INADDR_ANY), snum); unsigned int hash2_partial = ipv4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_rcv_saddr, 0); /* precompute partial secondary hash */ udp_sk(sk)->udp_portaddr_hash = hash2_partial; return udp_lib_get_port(sk, snum, hash2_nulladdr); } static int compute_score(struct sock *sk, struct net *net, __be32 saddr, __be16 sport, __be32 daddr, unsigned short hnum, int dif, int sdif) { int score; struct inet_sock *inet; bool dev_match; if (!net_eq(sock_net(sk), net) || udp_sk(sk)->udp_port_hash != hnum || ipv6_only_sock(sk)) return -1; if (sk->sk_rcv_saddr != daddr) return -1; score = (sk->sk_family == PF_INET) ? 2 : 1; inet = inet_sk(sk); if (inet->inet_daddr) { if (inet->inet_daddr != saddr) return -1; score += 4; } if (inet->inet_dport) { if (inet->inet_dport != sport) return -1; score += 4; } dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif); if (!dev_match) return -1; if (sk->sk_bound_dev_if) score += 4; if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id()) score++; return score; } INDIRECT_CALLABLE_SCOPE u32 udp_ehashfn(const struct net *net, const __be32 laddr, const __u16 lport, const __be32 faddr, const __be16 fport) { static u32 udp_ehash_secret __read_mostly; net_get_random_once(&udp_ehash_secret, sizeof(udp_ehash_secret)); return __inet_ehashfn(laddr, lport, faddr, fport, udp_ehash_secret + net_hash_mix(net)); } /* called with rcu_read_lock() */ static struct sock *udp4_lib_lookup2(struct net *net, __be32 saddr, __be16 sport, __be32 daddr, unsigned int hnum, int dif, int sdif, struct udp_hslot *hslot2, struct sk_buff *skb) { struct sock *sk, *result; int score, badness; result = NULL; badness = 0; udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { score = compute_score(sk, net, saddr, sport, daddr, hnum, dif, sdif); if (score > badness) { badness = score; if (sk->sk_state == TCP_ESTABLISHED) { result = sk; continue; } result = inet_lookup_reuseport(net, sk, skb, sizeof(struct udphdr), saddr, sport, daddr, hnum, udp_ehashfn); if (!result) { result = sk; continue; } /* Fall back to scoring if group has connections */ if (!reuseport_has_conns(sk)) return result; /* Reuseport logic returned an error, keep original score. */ if (IS_ERR(result)) continue; badness = compute_score(result, net, saddr, sport, daddr, hnum, dif, sdif); } } return result; } /* UDP is nearly always wildcards out the wazoo, it makes no sense to try * harder than this. -DaveM */ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport, __be32 daddr, __be16 dport, int dif, int sdif, struct udp_table *udptable, struct sk_buff *skb) { unsigned short hnum = ntohs(dport); unsigned int hash2, slot2; struct udp_hslot *hslot2; struct sock *result, *sk; hash2 = ipv4_portaddr_hash(net, daddr, hnum); slot2 = hash2 & udptable->mask; hslot2 = &udptable->hash2[slot2]; /* Lookup connected or non-wildcard socket */ result = udp4_lib_lookup2(net, saddr, sport, daddr, hnum, dif, sdif, hslot2, skb); if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED) goto done; /* Lookup redirect from BPF */ if (static_branch_unlikely(&bpf_sk_lookup_enabled) && udptable == net->ipv4.udp_table) { sk = inet_lookup_run_sk_lookup(net, IPPROTO_UDP, skb, sizeof(struct udphdr), saddr, sport, daddr, hnum, dif, udp_ehashfn); if (sk) { result = sk; goto done; } } /* Got non-wildcard socket or error on first lookup */ if (result) goto done; /* Lookup wildcard sockets */ hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum); slot2 = hash2 & udptable->mask; hslot2 = &udptable->hash2[slot2]; result = udp4_lib_lookup2(net, saddr, sport, htonl(INADDR_ANY), hnum, dif, sdif, hslot2, skb); done: if (IS_ERR(result)) return NULL; return result; } EXPORT_SYMBOL_GPL(__udp4_lib_lookup); static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb, __be16 sport, __be16 dport, struct udp_table *udptable) { const struct iphdr *iph = ip_hdr(skb); return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport, iph->daddr, dport, inet_iif(skb), inet_sdif(skb), udptable, skb); } struct sock *udp4_lib_lookup_skb(const struct sk_buff *skb, __be16 sport, __be16 dport) { const struct iphdr *iph = ip_hdr(skb); struct net *net = dev_net(skb->dev); int iif, sdif; inet_get_iif_sdif(skb, &iif, &sdif); return __udp4_lib_lookup(net, iph->saddr, sport, iph->daddr, dport, iif, sdif, net->ipv4.udp_table, NULL); } /* Must be called under rcu_read_lock(). * Does increment socket refcount. */ #if IS_ENABLED(CONFIG_NF_TPROXY_IPV4) || IS_ENABLED(CONFIG_NF_SOCKET_IPV4) struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport, __be32 daddr, __be16 dport, int dif) { struct sock *sk; sk = __udp4_lib_lookup(net, saddr, sport, daddr, dport, dif, 0, net->ipv4.udp_table, NULL); if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) sk = NULL; return sk; } EXPORT_SYMBOL_GPL(udp4_lib_lookup); #endif static inline bool __udp_is_mcast_sock(struct net *net, const struct sock *sk, __be16 loc_port, __be32 loc_addr, __be16 rmt_port, __be32 rmt_addr, int dif, int sdif, unsigned short hnum) { const struct inet_sock *inet = inet_sk(sk); if (!net_eq(sock_net(sk), net) || udp_sk(sk)->udp_port_hash != hnum || (inet->inet_daddr && inet->inet_daddr != rmt_addr) || (inet->inet_dport != rmt_port && inet->inet_dport) || (inet->inet_rcv_saddr && inet->inet_rcv_saddr != loc_addr) || ipv6_only_sock(sk) || !udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif)) return false; if (!ip_mc_sf_allow(sk, loc_addr, rmt_addr, dif, sdif)) return false; return true; } DEFINE_STATIC_KEY_FALSE(udp_encap_needed_key); void udp_encap_enable(void) { static_branch_inc(&udp_encap_needed_key); } EXPORT_SYMBOL(udp_encap_enable); void udp_encap_disable(void) { static_branch_dec(&udp_encap_needed_key); } EXPORT_SYMBOL(udp_encap_disable); /* Handler for tunnels with arbitrary destination ports: no socket lookup, go * through error handlers in encapsulations looking for a match. */ static int __udp4_lib_err_encap_no_sk(struct sk_buff *skb, u32 info) { int i; for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) { int (*handler)(struct sk_buff *skb, u32 info); const struct ip_tunnel_encap_ops *encap; encap = rcu_dereference(iptun_encaps[i]); if (!encap) continue; handler = encap->err_handler; if (handler && !handler(skb, info)) return 0; } return -ENOENT; } /* Try to match ICMP errors to UDP tunnels by looking up a socket without * reversing source and destination port: this will match tunnels that force the * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that * lwtunnels might actually break this assumption by being configured with * different destination ports on endpoints, in this case we won't be able to * trace ICMP messages back to them. * * If this doesn't match any socket, probe tunnels with arbitrary destination * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port * we've sent packets to won't necessarily match the local destination port. * * Then ask the tunnel implementation to match the error against a valid * association. * * Return an error if we can't find a match, the socket if we need further * processing, zero otherwise. */ static struct sock *__udp4_lib_err_encap(struct net *net, const struct iphdr *iph, struct udphdr *uh, struct udp_table *udptable, struct sock *sk, struct sk_buff *skb, u32 info) { int (*lookup)(struct sock *sk, struct sk_buff *skb); int network_offset, transport_offset; struct udp_sock *up; network_offset = skb_network_offset(skb); transport_offset = skb_transport_offset(skb); /* Network header needs to point to the outer IPv4 header inside ICMP */ skb_reset_network_header(skb); /* Transport header needs to point to the UDP header */ skb_set_transport_header(skb, iph->ihl << 2); if (sk) { up = udp_sk(sk); lookup = READ_ONCE(up->encap_err_lookup); if (lookup && lookup(sk, skb)) sk = NULL; goto out; } sk = __udp4_lib_lookup(net, iph->daddr, uh->source, iph->saddr, uh->dest, skb->dev->ifindex, 0, udptable, NULL); if (sk) { up = udp_sk(sk); lookup = READ_ONCE(up->encap_err_lookup); if (!lookup || lookup(sk, skb)) sk = NULL; } out: if (!sk) sk = ERR_PTR(__udp4_lib_err_encap_no_sk(skb, info)); skb_set_transport_header(skb, transport_offset); skb_set_network_header(skb, network_offset); return sk; } /* * This routine is called by the ICMP module when it gets some * sort of error condition. If err < 0 then the socket should * be closed and the error returned to the user. If err > 0 * it's just the icmp type << 8 | icmp code. * Header points to the ip header of the error packet. We move * on past this. Then (as it used to claim before adjustment) * header points to the first 8 bytes of the udp header. We need * to find the appropriate port. */ int __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable) { struct inet_sock *inet; const struct iphdr *iph = (const struct iphdr *)skb->data; struct udphdr *uh = (struct udphdr *)(skb->data+(iph->ihl<<2)); const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; bool tunnel = false; struct sock *sk; int harderr; int err; struct net *net = dev_net(skb->dev); sk = __udp4_lib_lookup(net, iph->daddr, uh->dest, iph->saddr, uh->source, skb->dev->ifindex, inet_sdif(skb), udptable, NULL); if (!sk || udp_sk(sk)->encap_type) { /* No socket for error: try tunnels before discarding */ if (static_branch_unlikely(&udp_encap_needed_key)) { sk = __udp4_lib_err_encap(net, iph, uh, udptable, sk, skb, info); if (!sk) return 0; } else sk = ERR_PTR(-ENOENT); if (IS_ERR(sk)) { __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); return PTR_ERR(sk); } tunnel = true; } err = 0; harderr = 0; inet = inet_sk(sk); switch (type) { default: case ICMP_TIME_EXCEEDED: err = EHOSTUNREACH; break; case ICMP_SOURCE_QUENCH: goto out; case ICMP_PARAMETERPROB: err = EPROTO; harderr = 1; break; case ICMP_DEST_UNREACH: if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */ ipv4_sk_update_pmtu(skb, sk, info); if (inet->pmtudisc != IP_PMTUDISC_DONT) { err = EMSGSIZE; harderr = 1; break; } goto out; } err = EHOSTUNREACH; if (code <= NR_ICMP_UNREACH) { harderr = icmp_err_convert[code].fatal; err = icmp_err_convert[code].errno; } break; case ICMP_REDIRECT: ipv4_sk_redirect(skb, sk); goto out; } /* * RFC1122: OK. Passes ICMP errors back to application, as per * 4.1.3.3. */ if (tunnel) { /* ...not for tunnels though: we don't have a sending socket */ if (udp_sk(sk)->encap_err_rcv) udp_sk(sk)->encap_err_rcv(sk, skb, err, uh->dest, info, (u8 *)(uh+1)); goto out; } if (!inet_test_bit(RECVERR, sk)) { if (!harderr || sk->sk_state != TCP_ESTABLISHED) goto out; } else ip_icmp_error(sk, skb, err, uh->dest, info, (u8 *)(uh+1)); sk->sk_err = err; sk_error_report(sk); out: return 0; } int udp_err(struct sk_buff *skb, u32 info) { return __udp4_lib_err(skb, info, dev_net(skb->dev)->ipv4.udp_table); } /* * Throw away all pending data and cancel the corking. Socket is locked. */ void udp_flush_pending_frames(struct sock *sk) { struct udp_sock *up = udp_sk(sk); if (up->pending) { up->len = 0; up->pending = 0; ip_flush_pending_frames(sk); } } EXPORT_SYMBOL(udp_flush_pending_frames); /** * udp4_hwcsum - handle outgoing HW checksumming * @skb: sk_buff containing the filled-in UDP header * (checksum field must be zeroed out) * @src: source IP address * @dst: destination IP address */ void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst) { struct udphdr *uh = udp_hdr(skb); int offset = skb_transport_offset(skb); int len = skb->len - offset; int hlen = len; __wsum csum = 0; if (!skb_has_frag_list(skb)) { /* * Only one fragment on the socket. */ skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = offsetof(struct udphdr, check); uh->check = ~csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, 0); } else { struct sk_buff *frags; /* * HW-checksum won't work as there are two or more * fragments on the socket so that all csums of sk_buffs * should be together */ skb_walk_frags(skb, frags) { csum = csum_add(csum, frags->csum); hlen -= frags->len; } csum = skb_checksum(skb, offset, hlen, csum); skb->ip_summed = CHECKSUM_NONE; uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum); if (uh->check == 0) uh->check = CSUM_MANGLED_0; } } EXPORT_SYMBOL_GPL(udp4_hwcsum); /* Function to set UDP checksum for an IPv4 UDP packet. This is intended * for the simple case like when setting the checksum for a UDP tunnel. */ void udp_set_csum(bool nocheck, struct sk_buff *skb, __be32 saddr, __be32 daddr, int len) { struct udphdr *uh = udp_hdr(skb); if (nocheck) { uh->check = 0; } else if (skb_is_gso(skb)) { uh->check = ~udp_v4_check(len, saddr, daddr, 0); } else if (skb->ip_summed == CHECKSUM_PARTIAL) { uh->check = 0; uh->check = udp_v4_check(len, saddr, daddr, lco_csum(skb)); if (uh->check == 0) uh->check = CSUM_MANGLED_0; } else { skb->ip_summed = CHECKSUM_PARTIAL; skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = offsetof(struct udphdr, check); uh->check = ~udp_v4_check(len, saddr, daddr, 0); } } EXPORT_SYMBOL(udp_set_csum); static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4, struct inet_cork *cork) { struct sock *sk = skb->sk; struct inet_sock *inet = inet_sk(sk); struct udphdr *uh; int err; int is_udplite = IS_UDPLITE(sk); int offset = skb_transport_offset(skb); int len = skb->len - offset; int datalen = len - sizeof(*uh); __wsum csum = 0; /* * Create a UDP header */ uh = udp_hdr(skb); uh->source = inet->inet_sport; uh->dest = fl4->fl4_dport; uh->len = htons(len); uh->check = 0; if (cork->gso_size) { const int hlen = skb_network_header_len(skb) + sizeof(struct udphdr); if (hlen + cork->gso_size > cork->fragsize) { kfree_skb(skb); return -EINVAL; } if (datalen > cork->gso_size * UDP_MAX_SEGMENTS) { kfree_skb(skb); return -EINVAL; } if (sk->sk_no_check_tx) { kfree_skb(skb); return -EINVAL; } if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite || dst_xfrm(skb_dst(skb))) { kfree_skb(skb); return -EIO; } if (datalen > cork->gso_size) { skb_shinfo(skb)->gso_size = cork->gso_size; skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4; skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen, cork->gso_size); } goto csum_partial; } if (is_udplite) /* UDP-Lite */ csum = udplite_csum(skb); else if (sk->sk_no_check_tx) { /* UDP csum off */ skb->ip_summed = CHECKSUM_NONE; goto send; } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ csum_partial: udp4_hwcsum(skb, fl4->saddr, fl4->daddr); goto send; } else csum = udp_csum(skb); /* add protocol-dependent pseudo-header */ uh->check = csum_tcpudp_magic(fl4->saddr, fl4->daddr, len, sk->sk_protocol, csum); if (uh->check == 0) uh->check = CSUM_MANGLED_0; send: err = ip_send_skb(sock_net(sk), skb); if (err) { if (err == -ENOBUFS && !inet_test_bit(RECVERR, sk)) { UDP_INC_STATS(sock_net(sk), UDP_MIB_SNDBUFERRORS, is_udplite); err = 0; } } else UDP_INC_STATS(sock_net(sk), UDP_MIB_OUTDATAGRAMS, is_udplite); return err; } /* * Push out all pending data as one UDP datagram. Socket is locked. */ int udp_push_pending_frames(struct sock *sk) { struct udp_sock *up = udp_sk(sk); struct inet_sock *inet = inet_sk(sk); struct flowi4 *fl4 = &inet->cork.fl.u.ip4; struct sk_buff *skb; int err = 0; skb = ip_finish_skb(sk, fl4); if (!skb) goto out; err = udp_send_skb(skb, fl4, &inet->cork.base); out: up->len = 0; up->pending = 0; return err; } EXPORT_SYMBOL(udp_push_pending_frames); static int __udp_cmsg_send(struct cmsghdr *cmsg, u16 *gso_size) { switch (cmsg->cmsg_type) { case UDP_SEGMENT: if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u16))) return -EINVAL; *gso_size = *(__u16 *)CMSG_DATA(cmsg); return 0; default: return -EINVAL; } } int udp_cmsg_send(struct sock *sk, struct msghdr *msg, u16 *gso_size) { struct cmsghdr *cmsg; bool need_ip = false; int err; for_each_cmsghdr(cmsg, msg) { if (!CMSG_OK(msg, cmsg)) return -EINVAL; if (cmsg->cmsg_level != SOL_UDP) { need_ip = true; continue; } err = __udp_cmsg_send(cmsg, gso_size); if (err) return err; } return need_ip; } EXPORT_SYMBOL_GPL(udp_cmsg_send); int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) { struct inet_sock *inet = inet_sk(sk); struct udp_sock *up = udp_sk(sk); DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name); struct flowi4 fl4_stack; struct flowi4 *fl4; int ulen = len; struct ipcm_cookie ipc; struct rtable *rt = NULL; int free = 0; int connected = 0; __be32 daddr, faddr, saddr; u8 tos, scope; __be16 dport; int err, is_udplite = IS_UDPLITE(sk); int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE; int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); struct sk_buff *skb; struct ip_options_data opt_copy; if (len > 0xFFFF) return -EMSGSIZE; /* * Check the flags. */ if (msg->msg_flags & MSG_OOB) /* Mirror BSD error message compatibility */ return -EOPNOTSUPP; getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; fl4 = &inet->cork.fl.u.ip4; if (up->pending) { /* * There are pending frames. * The socket lock must be held while it's corked. */ lock_sock(sk); if (likely(up->pending)) { if (unlikely(up->pending != AF_INET)) { release_sock(sk); return -EINVAL; } goto do_append_data; } release_sock(sk); } ulen += sizeof(struct udphdr); /* * Get and verify the address. */ if (usin) { if (msg->msg_namelen < sizeof(*usin)) return -EINVAL; if (usin->sin_family != AF_INET) { if (usin->sin_family != AF_UNSPEC) return -EAFNOSUPPORT; } daddr = usin->sin_addr.s_addr; dport = usin->sin_port; if (dport == 0) return -EINVAL; } else { if (sk->sk_state != TCP_ESTABLISHED) return -EDESTADDRREQ; daddr = inet->inet_daddr; dport = inet->inet_dport; /* Open fast path for connected socket. Route will not be used, if at least one option is set. */ connected = 1; } ipcm_init_sk(&ipc, inet); ipc.gso_size = READ_ONCE(up->gso_size); if (msg->msg_controllen) { err = udp_cmsg_send(sk, msg, &ipc.gso_size); if (err > 0) err = ip_cmsg_send(sk, msg, &ipc, sk->sk_family == AF_INET6); if (unlikely(err < 0)) { kfree(ipc.opt); return err; } if (ipc.opt) free = 1; connected = 0; } if (!ipc.opt) { struct ip_options_rcu *inet_opt; rcu_read_lock(); inet_opt = rcu_dereference(inet->inet_opt); if (inet_opt) { memcpy(&opt_copy, inet_opt, sizeof(*inet_opt) + inet_opt->opt.optlen); ipc.opt = &opt_copy.opt; } rcu_read_unlock(); } if (cgroup_bpf_enabled(CGROUP_UDP4_SENDMSG) && !connected) { err = BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, (struct sockaddr *)usin, &ipc.addr); if (err) goto out_free; if (usin) { if (usin->sin_port == 0) { /* BPF program set invalid port. Reject it. */ err = -EINVAL; goto out_free; } daddr = usin->sin_addr.s_addr; dport = usin->sin_port; } } saddr = ipc.addr; ipc.addr = faddr = daddr; if (ipc.opt && ipc.opt->opt.srr) { if (!daddr) { err = -EINVAL; goto out_free; } faddr = ipc.opt->opt.faddr; connected = 0; } tos = get_rttos(&ipc, inet); scope = ip_sendmsg_scope(inet, &ipc, msg); if (scope == RT_SCOPE_LINK) connected = 0; if (ipv4_is_multicast(daddr)) { if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif)) ipc.oif = inet->mc_index; if (!saddr) saddr = inet->mc_addr; connected = 0; } else if (!ipc.oif) { ipc.oif = inet->uc_index; } else if (ipv4_is_lbcast(daddr) && inet->uc_index) { /* oif is set, packet is to local broadcast and * uc_index is set. oif is most likely set * by sk_bound_dev_if. If uc_index != oif check if the * oif is an L3 master and uc_index is an L3 slave. * If so, we want to allow the send using the uc_index. */ if (ipc.oif != inet->uc_index && ipc.oif == l3mdev_master_ifindex_by_index(sock_net(sk), inet->uc_index)) { ipc.oif = inet->uc_index; } } if (connected) rt = (struct rtable *)sk_dst_check(sk, 0); if (!rt) { struct net *net = sock_net(sk); __u8 flow_flags = inet_sk_flowi_flags(sk); fl4 = &fl4_stack; flowi4_init_output(fl4, ipc.oif, ipc.sockc.mark, tos, scope, sk->sk_protocol, flow_flags, faddr, saddr, dport, inet->inet_sport, sk->sk_uid); security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4)); rt = ip_route_output_flow(net, fl4, sk); if (IS_ERR(rt)) { err = PTR_ERR(rt); rt = NULL; if (err == -ENETUNREACH) IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); goto out; } err = -EACCES; if ((rt->rt_flags & RTCF_BROADCAST) && !sock_flag(sk, SOCK_BROADCAST)) goto out; if (connected) sk_dst_set(sk, dst_clone(&rt->dst)); } if (msg->msg_flags&MSG_CONFIRM) goto do_confirm; back_from_confirm: saddr = fl4->saddr; if (!ipc.addr) daddr = ipc.addr = fl4->daddr; /* Lockless fast path for the non-corking case. */ if (!corkreq) { struct inet_cork cork; skb = ip_make_skb(sk, fl4, getfrag, msg, ulen, sizeof(struct udphdr), &ipc, &rt, &cork, msg->msg_flags); err = PTR_ERR(skb); if (!IS_ERR_OR_NULL(skb)) err = udp_send_skb(skb, fl4, &cork); goto out; } lock_sock(sk); if (unlikely(up->pending)) { /* The socket is already corked while preparing it. */ /* ... which is an evident application bug. --ANK */ release_sock(sk); net_dbg_ratelimited("socket already corked\n"); err = -EINVAL; goto out; } /* * Now cork the socket to pend data. */ fl4 = &inet->cork.fl.u.ip4; fl4->daddr = daddr; fl4->saddr = saddr; fl4->fl4_dport = dport; fl4->fl4_sport = inet->inet_sport; up->pending = AF_INET; do_append_data: up->len += ulen; err = ip_append_data(sk, fl4, getfrag, msg, ulen, sizeof(struct udphdr), &ipc, &rt, corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags); if (err) udp_flush_pending_frames(sk); else if (!corkreq) err = udp_push_pending_frames(sk); else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) up->pending = 0; release_sock(sk); out: ip_rt_put(rt); out_free: if (free) kfree(ipc.opt); if (!err) return len; /* * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting * ENOBUFS might not be good (it's not tunable per se), but otherwise * we don't have a good statistic (IpOutDiscards but it can be too many * things). We could add another new stat but at least for now that * seems like overkill. */ if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { UDP_INC_STATS(sock_net(sk), UDP_MIB_SNDBUFERRORS, is_udplite); } return err; do_confirm: if (msg->msg_flags & MSG_PROBE) dst_confirm_neigh(&rt->dst, &fl4->daddr); if (!(msg->msg_flags&MSG_PROBE) || len) goto back_from_confirm; err = 0; goto out; } EXPORT_SYMBOL(udp_sendmsg); void udp_splice_eof(struct socket *sock) { struct sock *sk = sock->sk; struct udp_sock *up = udp_sk(sk); if (!up->pending || READ_ONCE(up->corkflag)) return; lock_sock(sk); if (up->pending && !READ_ONCE(up->corkflag)) udp_push_pending_frames(sk); release_sock(sk); } EXPORT_SYMBOL_GPL(udp_splice_eof); #define UDP_SKB_IS_STATELESS 0x80000000 /* all head states (dst, sk, nf conntrack) except skb extensions are * cleared by udp_rcv(). * * We need to preserve secpath, if present, to eventually process * IP_CMSG_PASSSEC at recvmsg() time. * * Other extensions can be cleared. */ static bool udp_try_make_stateless(struct sk_buff *skb) { if (!skb_has_extensions(skb)) return true; if (!secpath_exists(skb)) { skb_ext_reset(skb); return true; } return false; } static void udp_set_dev_scratch(struct sk_buff *skb) { struct udp_dev_scratch *scratch = udp_skb_scratch(skb); BUILD_BUG_ON(sizeof(struct udp_dev_scratch) > sizeof(long)); scratch->_tsize_state = skb->truesize; #if BITS_PER_LONG == 64 scratch->len = skb->len; scratch->csum_unnecessary = !!skb_csum_unnecessary(skb); scratch->is_linear = !skb_is_nonlinear(skb); #endif if (udp_try_make_stateless(skb)) scratch->_tsize_state |= UDP_SKB_IS_STATELESS; } static void udp_skb_csum_unnecessary_set(struct sk_buff *skb) { /* We come here after udp_lib_checksum_complete() returned 0. * This means that __skb_checksum_complete() might have * set skb->csum_valid to 1. * On 64bit platforms, we can set csum_unnecessary * to true, but only if the skb is not shared. */ #if BITS_PER_LONG == 64 if (!skb_shared(skb)) udp_skb_scratch(skb)->csum_unnecessary = true; #endif } static int udp_skb_truesize(struct sk_buff *skb) { return udp_skb_scratch(skb)->_tsize_state & ~UDP_SKB_IS_STATELESS; } static bool udp_skb_has_head_state(struct sk_buff *skb) { return !(udp_skb_scratch(skb)->_tsize_state & UDP_SKB_IS_STATELESS); } /* fully reclaim rmem/fwd memory allocated for skb */ static void udp_rmem_release(struct sock *sk, int size, int partial, bool rx_queue_lock_held) { struct udp_sock *up = udp_sk(sk); struct sk_buff_head *sk_queue; int amt; if (likely(partial)) { up->forward_deficit += size; size = up->forward_deficit; if (size < READ_ONCE(up->forward_threshold) && !skb_queue_empty(&up->reader_queue)) return; } else { size += up->forward_deficit; } up->forward_deficit = 0; /* acquire the sk_receive_queue for fwd allocated memory scheduling, * if the called don't held it already */ sk_queue = &sk->sk_receive_queue; if (!rx_queue_lock_held) spin_lock(&sk_queue->lock); sk_forward_alloc_add(sk, size); amt = (sk->sk_forward_alloc - partial) & ~(PAGE_SIZE - 1); sk_forward_alloc_add(sk, -amt); if (amt) __sk_mem_reduce_allocated(sk, amt >> PAGE_SHIFT); atomic_sub(size, &sk->sk_rmem_alloc); /* this can save us from acquiring the rx queue lock on next receive */ skb_queue_splice_tail_init(sk_queue, &up->reader_queue); if (!rx_queue_lock_held) spin_unlock(&sk_queue->lock); } /* Note: called with reader_queue.lock held. * Instead of using skb->truesize here, find a copy of it in skb->dev_scratch * This avoids a cache line miss while receive_queue lock is held. * Look at __udp_enqueue_schedule_skb() to find where this copy is done. */ void udp_skb_destructor(struct sock *sk, struct sk_buff *skb) { prefetch(&skb->data); udp_rmem_release(sk, udp_skb_truesize(skb), 1, false); } EXPORT_SYMBOL(udp_skb_destructor); /* as above, but the caller held the rx queue lock, too */ static void udp_skb_dtor_locked(struct sock *sk, struct sk_buff *skb) { prefetch(&skb->data); udp_rmem_release(sk, udp_skb_truesize(skb), 1, true); } /* Idea of busylocks is to let producers grab an extra spinlock * to relieve pressure on the receive_queue spinlock shared by consumer. * Under flood, this means that only one producer can be in line * trying to acquire the receive_queue spinlock. * These busylock can be allocated on a per cpu manner, instead of a * per socket one (that would consume a cache line per socket) */ static int udp_busylocks_log __read_mostly; static spinlock_t *udp_busylocks __read_mostly; static spinlock_t *busylock_acquire(void *ptr) { spinlock_t *busy; busy = udp_busylocks + hash_ptr(ptr, udp_busylocks_log); spin_lock(busy); return busy; } static void busylock_release(spinlock_t *busy) { if (busy) spin_unlock(busy); } static int udp_rmem_schedule(struct sock *sk, int size) { int delta; delta = size - sk->sk_forward_alloc; if (delta > 0 && !__sk_mem_schedule(sk, delta, SK_MEM_RECV)) return -ENOBUFS; return 0; } int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb) { struct sk_buff_head *list = &sk->sk_receive_queue; int rmem, err = -ENOMEM; spinlock_t *busy = NULL; int size; /* try to avoid the costly atomic add/sub pair when the receive * queue is full; always allow at least a packet */ rmem = atomic_read(&sk->sk_rmem_alloc); if (rmem > sk->sk_rcvbuf) goto drop; /* Under mem pressure, it might be helpful to help udp_recvmsg() * having linear skbs : * - Reduce memory overhead and thus increase receive queue capacity * - Less cache line misses at copyout() time * - Less work at consume_skb() (less alien page frag freeing) */ if (rmem > (sk->sk_rcvbuf >> 1)) { skb_condense(skb); busy = busylock_acquire(sk); } size = skb->truesize; udp_set_dev_scratch(skb); /* we drop only if the receive buf is full and the receive * queue contains some other skb */ rmem = atomic_add_return(size, &sk->sk_rmem_alloc); if (rmem > (size + (unsigned int)sk->sk_rcvbuf)) goto uncharge_drop; spin_lock(&list->lock); err = udp_rmem_schedule(sk, size); if (err) { spin_unlock(&list->lock); goto uncharge_drop; } sk_forward_alloc_add(sk, -size); /* no need to setup a destructor, we will explicitly release the * forward allocated memory on dequeue */ sock_skb_set_dropcount(sk, skb); __skb_queue_tail(list, skb); spin_unlock(&list->lock); if (!sock_flag(sk, SOCK_DEAD)) INDIRECT_CALL_1(sk->sk_data_ready, sock_def_readable, sk); busylock_release(busy); return 0; uncharge_drop: atomic_sub(skb->truesize, &sk->sk_rmem_alloc); drop: atomic_inc(&sk->sk_drops); busylock_release(busy); return err; } EXPORT_SYMBOL_GPL(__udp_enqueue_schedule_skb); void udp_destruct_common(struct sock *sk) { /* reclaim completely the forward allocated memory */ struct udp_sock *up = udp_sk(sk); unsigned int total = 0; struct sk_buff *skb; skb_queue_splice_tail_init(&sk->sk_receive_queue, &up->reader_queue); while ((skb = __skb_dequeue(&up->reader_queue)) != NULL) { total += skb->truesize; kfree_skb(skb); } udp_rmem_release(sk, total, 0, true); } EXPORT_SYMBOL_GPL(udp_destruct_common); static void udp_destruct_sock(struct sock *sk) { udp_destruct_common(sk); inet_sock_destruct(sk); } int udp_init_sock(struct sock *sk) { udp_lib_init_sock(sk); sk->sk_destruct = udp_destruct_sock; set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); return 0; } void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len) { if (unlikely(READ_ONCE(sk->sk_peek_off) >= 0)) { bool slow = lock_sock_fast(sk); sk_peek_offset_bwd(sk, len); unlock_sock_fast(sk, slow); } if (!skb_unref(skb)) return; /* In the more common cases we cleared the head states previously, * see __udp_queue_rcv_skb(). */ if (unlikely(udp_skb_has_head_state(skb))) skb_release_head_state(skb); __consume_stateless_skb(skb); } EXPORT_SYMBOL_GPL(skb_consume_udp); static struct sk_buff *__first_packet_length(struct sock *sk, struct sk_buff_head *rcvq, int *total) { struct sk_buff *skb; while ((skb = skb_peek(rcvq)) != NULL) { if (udp_lib_checksum_complete(skb)) { __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, IS_UDPLITE(sk)); __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, IS_UDPLITE(sk)); atomic_inc(&sk->sk_drops); __skb_unlink(skb, rcvq); *total += skb->truesize; kfree_skb(skb); } else { udp_skb_csum_unnecessary_set(skb); break; } } return skb; } /** * first_packet_length - return length of first packet in receive queue * @sk: socket * * Drops all bad checksum frames, until a valid one is found. * Returns the length of found skb, or -1 if none is found. */ static int first_packet_length(struct sock *sk) { struct sk_buff_head *rcvq = &udp_sk(sk)->reader_queue; struct sk_buff_head *sk_queue = &sk->sk_receive_queue; struct sk_buff *skb; int total = 0; int res; spin_lock_bh(&rcvq->lock); skb = __first_packet_length(sk, rcvq, &total); if (!skb && !skb_queue_empty_lockless(sk_queue)) { spin_lock(&sk_queue->lock); skb_queue_splice_tail_init(sk_queue, rcvq); spin_unlock(&sk_queue->lock); skb = __first_packet_length(sk, rcvq, &total); } res = skb ? skb->len : -1; if (total) udp_rmem_release(sk, total, 1, false); spin_unlock_bh(&rcvq->lock); return res; } /* * IOCTL requests applicable to the UDP protocol */ int udp_ioctl(struct sock *sk, int cmd, int *karg) { switch (cmd) { case SIOCOUTQ: { *karg = sk_wmem_alloc_get(sk); return 0; } case SIOCINQ: { *karg = max_t(int, 0, first_packet_length(sk)); return 0; } default: return -ENOIOCTLCMD; } return 0; } EXPORT_SYMBOL(udp_ioctl); struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags, int *off, int *err) { struct sk_buff_head *sk_queue = &sk->sk_receive_queue; struct sk_buff_head *queue; struct sk_buff *last; long timeo; int error; queue = &udp_sk(sk)->reader_queue; timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); do { struct sk_buff *skb; error = sock_error(sk); if (error) break; error = -EAGAIN; do { spin_lock_bh(&queue->lock); skb = __skb_try_recv_from_queue(sk, queue, flags, off, err, &last); if (skb) { if (!(flags & MSG_PEEK)) udp_skb_destructor(sk, skb); spin_unlock_bh(&queue->lock); return skb; } if (skb_queue_empty_lockless(sk_queue)) { spin_unlock_bh(&queue->lock); goto busy_check; } /* refill the reader queue and walk it again * keep both queues locked to avoid re-acquiring * the sk_receive_queue lock if fwd memory scheduling * is needed. */ spin_lock(&sk_queue->lock); skb_queue_splice_tail_init(sk_queue, queue); skb = __skb_try_recv_from_queue(sk, queue, flags, off, err, &last); if (skb && !(flags & MSG_PEEK)) udp_skb_dtor_locked(sk, skb); spin_unlock(&sk_queue->lock); spin_unlock_bh(&queue->lock); if (skb) return skb; busy_check: if (!sk_can_busy_loop(sk)) break; sk_busy_loop(sk, flags & MSG_DONTWAIT); } while (!skb_queue_empty_lockless(sk_queue)); /* sk_queue is empty, reader_queue may contain peeked packets */ } while (timeo && !__skb_wait_for_more_packets(sk, &sk->sk_receive_queue, &error, &timeo, (struct sk_buff *)sk_queue)); *err = error; return NULL; } EXPORT_SYMBOL(__skb_recv_udp); int udp_read_skb(struct sock *sk, skb_read_actor_t recv_actor) { struct sk_buff *skb; int err; try_again: skb = skb_recv_udp(sk, MSG_DONTWAIT, &err); if (!skb) return err; if (udp_lib_checksum_complete(skb)) { int is_udplite = IS_UDPLITE(sk); struct net *net = sock_net(sk); __UDP_INC_STATS(net, UDP_MIB_CSUMERRORS, is_udplite); __UDP_INC_STATS(net, UDP_MIB_INERRORS, is_udplite); atomic_inc(&sk->sk_drops); kfree_skb(skb); goto try_again; } WARN_ON_ONCE(!skb_set_owner_sk_safe(skb, sk)); return recv_actor(sk, skb); } EXPORT_SYMBOL(udp_read_skb); /* * This should be easy, if there is something there we * return it, otherwise we block. */ int udp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { struct inet_sock *inet = inet_sk(sk); DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); struct sk_buff *skb; unsigned int ulen, copied; int off, err, peeking = flags & MSG_PEEK; int is_udplite = IS_UDPLITE(sk); bool checksum_valid = false; if (flags & MSG_ERRQUEUE) return ip_recv_error(sk, msg, len, addr_len); try_again: off = sk_peek_offset(sk, flags); skb = __skb_recv_udp(sk, flags, &off, &err); if (!skb) return err; ulen = udp_skb_len(skb); copied = len; if (copied > ulen - off) copied = ulen - off; else if (copied < ulen) msg->msg_flags |= MSG_TRUNC; /* * If checksum is needed at all, try to do it while copying the * data. If the data is truncated, or if we only want a partial * coverage checksum (UDP-Lite), do it before the copy. */ if (copied < ulen || peeking || (is_udplite && UDP_SKB_CB(skb)->partial_cov)) { checksum_valid = udp_skb_csum_unnecessary(skb) || !__udp_lib_checksum_complete(skb); if (!checksum_valid) goto csum_copy_err; } if (checksum_valid || udp_skb_csum_unnecessary(skb)) { if (udp_skb_is_linear(skb)) err = copy_linear_skb(skb, copied, off, &msg->msg_iter); else err = skb_copy_datagram_msg(skb, off, msg, copied); } else { err = skb_copy_and_csum_datagram_msg(skb, off, msg); if (err == -EINVAL) goto csum_copy_err; } if (unlikely(err)) { if (!peeking) { atomic_inc(&sk->sk_drops); UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); } kfree_skb(skb); return err; } if (!peeking) UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS, is_udplite); sock_recv_cmsgs(msg, sk, skb); /* Copy the address. */ if (sin) { sin->sin_family = AF_INET; sin->sin_port = udp_hdr(skb)->source; sin->sin_addr.s_addr = ip_hdr(skb)->saddr; memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); *addr_len = sizeof(*sin); BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, (struct sockaddr *)sin); } if (udp_sk(sk)->gro_enabled) udp_cmsg_recv(msg, sk, skb); if (inet_cmsg_flags(inet)) ip_cmsg_recv_offset(msg, sk, skb, sizeof(struct udphdr), off); err = copied; if (flags & MSG_TRUNC) err = ulen; skb_consume_udp(sk, skb, peeking ? -err : err); return err; csum_copy_err: if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags, udp_skb_destructor)) { UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); } kfree_skb(skb); /* starting over for a new packet, but check if we need to yield */ cond_resched(); msg->msg_flags &= ~MSG_TRUNC; goto try_again; } int udp_pre_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { /* This check is replicated from __ip4_datagram_connect() and * intended to prevent BPF program called below from accessing bytes * that are out of the bound specified by user in addr_len. */ if (addr_len < sizeof(struct sockaddr_in)) return -EINVAL; return BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr); } EXPORT_SYMBOL(udp_pre_connect); int __udp_disconnect(struct sock *sk, int flags) { struct inet_sock *inet = inet_sk(sk); /* * 1003.1g - break association. */ sk->sk_state = TCP_CLOSE; inet->inet_daddr = 0; inet->inet_dport = 0; sock_rps_reset_rxhash(sk); sk->sk_bound_dev_if = 0; if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) { inet_reset_saddr(sk); if (sk->sk_prot->rehash && (sk->sk_userlocks & SOCK_BINDPORT_LOCK)) sk->sk_prot->rehash(sk); } if (!(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) { sk->sk_prot->unhash(sk); inet->inet_sport = 0; } sk_dst_reset(sk); return 0; } EXPORT_SYMBOL(__udp_disconnect); int udp_disconnect(struct sock *sk, int flags) { lock_sock(sk); __udp_disconnect(sk, flags); release_sock(sk); return 0; } EXPORT_SYMBOL(udp_disconnect); void udp_lib_unhash(struct sock *sk) { if (sk_hashed(sk)) { struct udp_table *udptable = udp_get_table_prot(sk); struct udp_hslot *hslot, *hslot2; hslot = udp_hashslot(udptable, sock_net(sk), udp_sk(sk)->udp_port_hash); hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash); spin_lock_bh(&hslot->lock); if (rcu_access_pointer(sk->sk_reuseport_cb)) reuseport_detach_sock(sk); if (sk_del_node_init_rcu(sk)) { hslot->count--; inet_sk(sk)->inet_num = 0; sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); spin_lock(&hslot2->lock); hlist_del_init_rcu(&udp_sk(sk)->udp_portaddr_node); hslot2->count--; spin_unlock(&hslot2->lock); } spin_unlock_bh(&hslot->lock); } } EXPORT_SYMBOL(udp_lib_unhash); /* * inet_rcv_saddr was changed, we must rehash secondary hash */ void udp_lib_rehash(struct sock *sk, u16 newhash) { if (sk_hashed(sk)) { struct udp_table *udptable = udp_get_table_prot(sk); struct udp_hslot *hslot, *hslot2, *nhslot2; hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash); nhslot2 = udp_hashslot2(udptable, newhash); udp_sk(sk)->udp_portaddr_hash = newhash; if (hslot2 != nhslot2 || rcu_access_pointer(sk->sk_reuseport_cb)) { hslot = udp_hashslot(udptable, sock_net(sk), udp_sk(sk)->udp_port_hash); /* we must lock primary chain too */ spin_lock_bh(&hslot->lock); if (rcu_access_pointer(sk->sk_reuseport_cb)) reuseport_detach_sock(sk); if (hslot2 != nhslot2) { spin_lock(&hslot2->lock); hlist_del_init_rcu(&udp_sk(sk)->udp_portaddr_node); hslot2->count--; spin_unlock(&hslot2->lock); spin_lock(&nhslot2->lock); hlist_add_head_rcu(&udp_sk(sk)->udp_portaddr_node, &nhslot2->head); nhslot2->count++; spin_unlock(&nhslot2->lock); } spin_unlock_bh(&hslot->lock); } } } EXPORT_SYMBOL(udp_lib_rehash); void udp_v4_rehash(struct sock *sk) { u16 new_hash = ipv4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_rcv_saddr, inet_sk(sk)->inet_num); udp_lib_rehash(sk, new_hash); } static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) { int rc; if (inet_sk(sk)->inet_daddr) { sock_rps_save_rxhash(sk, skb); sk_mark_napi_id(sk, skb); sk_incoming_cpu_update(sk); } else { sk_mark_napi_id_once(sk, skb); } rc = __udp_enqueue_schedule_skb(sk, skb); if (rc < 0) { int is_udplite = IS_UDPLITE(sk); int drop_reason; /* Note that an ENOMEM error is charged twice */ if (rc == -ENOMEM) { UDP_INC_STATS(sock_net(sk), UDP_MIB_RCVBUFERRORS, is_udplite); drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF; } else { UDP_INC_STATS(sock_net(sk), UDP_MIB_MEMERRORS, is_udplite); drop_reason = SKB_DROP_REASON_PROTO_MEM; } UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); kfree_skb_reason(skb, drop_reason); trace_udp_fail_queue_rcv_skb(rc, sk); return -1; } return 0; } /* returns: * -1: error * 0: success * >0: "udp encap" protocol resubmission * * Note that in the success and error cases, the skb is assumed to * have either been requeued or freed. */ static int udp_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb) { int drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; struct udp_sock *up = udp_sk(sk); int is_udplite = IS_UDPLITE(sk); /* * Charge it to the socket, dropping if the queue is full. */ if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) { drop_reason = SKB_DROP_REASON_XFRM_POLICY; goto drop; } nf_reset_ct(skb); if (static_branch_unlikely(&udp_encap_needed_key) && up->encap_type) { int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); /* * This is an encapsulation socket so pass the skb to * the socket's udp_encap_rcv() hook. Otherwise, just * fall through and pass this up the UDP socket. * up->encap_rcv() returns the following value: * =0 if skb was successfully passed to the encap * handler or was discarded by it. * >0 if skb should be passed on to UDP. * <0 if skb should be resubmitted as proto -N */ /* if we're overly short, let UDP handle it */ encap_rcv = READ_ONCE(up->encap_rcv); if (encap_rcv) { int ret; /* Verify checksum before giving to encap */ if (udp_lib_checksum_complete(skb)) goto csum_error; ret = encap_rcv(sk, skb); if (ret <= 0) { __UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS, is_udplite); return -ret; } } /* FALLTHROUGH -- it's a UDP Packet */ } /* * UDP-Lite specific tests, ignored on UDP sockets */ if ((up->pcflag & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { /* * MIB statistics other than incrementing the error count are * disabled for the following two types of errors: these depend * on the application settings, not on the functioning of the * protocol stack as such. * * RFC 3828 here recommends (sec 3.3): "There should also be a * way ... to ... at least let the receiving application block * delivery of packets with coverage values less than a value * provided by the application." */ if (up->pcrlen == 0) { /* full coverage was set */ net_dbg_ratelimited("UDPLite: partial coverage %d while full coverage %d requested\n", UDP_SKB_CB(skb)->cscov, skb->len); goto drop; } /* The next case involves violating the min. coverage requested * by the receiver. This is subtle: if receiver wants x and x is * greater than the buffersize/MTU then receiver will complain * that it wants x while sender emits packets of smaller size y. * Therefore the above ...()->partial_cov statement is essential. */ if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { net_dbg_ratelimited("UDPLite: coverage %d too small, need min %d\n", UDP_SKB_CB(skb)->cscov, up->pcrlen); goto drop; } } prefetch(&sk->sk_rmem_alloc); if (rcu_access_pointer(sk->sk_filter) && udp_lib_checksum_complete(skb)) goto csum_error; if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) { drop_reason = SKB_DROP_REASON_SOCKET_FILTER; goto drop; } udp_csum_pull_header(skb); ipv4_pktinfo_prepare(sk, skb); return __udp_queue_rcv_skb(sk, skb); csum_error: drop_reason = SKB_DROP_REASON_UDP_CSUM; __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); drop: __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); atomic_inc(&sk->sk_drops); kfree_skb_reason(skb, drop_reason); return -1; } static int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) { struct sk_buff *next, *segs; int ret; if (likely(!udp_unexpected_gso(sk, skb))) return udp_queue_rcv_one_skb(sk, skb); BUILD_BUG_ON(sizeof(struct udp_skb_cb) > SKB_GSO_CB_OFFSET); __skb_push(skb, -skb_mac_offset(skb)); segs = udp_rcv_segment(sk, skb, true); skb_list_walk_safe(segs, skb, next) { __skb_pull(skb, skb_transport_offset(skb)); udp_post_segment_fix_csum(skb); ret = udp_queue_rcv_one_skb(sk, skb); if (ret > 0) ip_protocol_deliver_rcu(dev_net(skb->dev), skb, ret); } return 0; } /* For TCP sockets, sk_rx_dst is protected by socket lock * For UDP, we use xchg() to guard against concurrent changes. */ bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst) { struct dst_entry *old; if (dst_hold_safe(dst)) { old = xchg((__force struct dst_entry **)&sk->sk_rx_dst, dst); dst_release(old); return old != dst; } return false; } EXPORT_SYMBOL(udp_sk_rx_dst_set); /* * Multicasts and broadcasts go to each listener. * * Note: called only from the BH handler context. */ static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb, struct udphdr *uh, __be32 saddr, __be32 daddr, struct udp_table *udptable, int proto) { struct sock *sk, *first = NULL; unsigned short hnum = ntohs(uh->dest); struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum); unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10); unsigned int offset = offsetof(typeof(*sk), sk_node); int dif = skb->dev->ifindex; int sdif = inet_sdif(skb); struct hlist_node *node; struct sk_buff *nskb; if (use_hash2) { hash2_any = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum) & udptable->mask; hash2 = ipv4_portaddr_hash(net, daddr, hnum) & udptable->mask; start_lookup: hslot = &udptable->hash2[hash2]; offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node); } sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) { if (!__udp_is_mcast_sock(net, sk, uh->dest, daddr, uh->source, saddr, dif, sdif, hnum)) continue; if (!first) { first = sk; continue; } nskb = skb_clone(skb, GFP_ATOMIC); if (unlikely(!nskb)) { atomic_inc(&sk->sk_drops); __UDP_INC_STATS(net, UDP_MIB_RCVBUFERRORS, IS_UDPLITE(sk)); __UDP_INC_STATS(net, UDP_MIB_INERRORS, IS_UDPLITE(sk)); continue; } if (udp_queue_rcv_skb(sk, nskb) > 0) consume_skb(nskb); } /* Also lookup *:port if we are using hash2 and haven't done so yet. */ if (use_hash2 && hash2 != hash2_any) { hash2 = hash2_any; goto start_lookup; } if (first) { if (udp_queue_rcv_skb(first, skb) > 0) consume_skb(skb); } else { kfree_skb(skb); __UDP_INC_STATS(net, UDP_MIB_IGNOREDMULTI, proto == IPPROTO_UDPLITE); } return 0; } /* Initialize UDP checksum. If exited with zero value (success), * CHECKSUM_UNNECESSARY means, that no more checks are required. * Otherwise, csum completion requires checksumming packet body, * including udp header and folding it to skb->csum. */ static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto) { int err; UDP_SKB_CB(skb)->partial_cov = 0; UDP_SKB_CB(skb)->cscov = skb->len; if (proto == IPPROTO_UDPLITE) { err = udplite_checksum_init(skb, uh); if (err) return err; if (UDP_SKB_CB(skb)->partial_cov) { skb->csum = inet_compute_pseudo(skb, proto); return 0; } } /* Note, we are only interested in != 0 or == 0, thus the * force to int. */ err = (__force int)skb_checksum_init_zero_check(skb, proto, uh->check, inet_compute_pseudo); if (err) return err; if (skb->ip_summed == CHECKSUM_COMPLETE && !skb->csum_valid) { /* If SW calculated the value, we know it's bad */ if (skb->csum_complete_sw) return 1; /* HW says the value is bad. Let's validate that. * skb->csum is no longer the full packet checksum, * so don't treat it as such. */ skb_checksum_complete_unset(skb); } return 0; } /* wrapper for udp_queue_rcv_skb tacking care of csum conversion and * return code conversion for ip layer consumption */ static int udp_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb, struct udphdr *uh) { int ret; if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk)) skb_checksum_try_convert(skb, IPPROTO_UDP, inet_compute_pseudo); ret = udp_queue_rcv_skb(sk, skb); /* a return value > 0 means to resubmit the input, but * it wants the return to be -protocol, or 0 */ if (ret > 0) return -ret; return 0; } /* * All we need to do is get the socket, and then do a checksum. */ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, int proto) { struct sock *sk; struct udphdr *uh; unsigned short ulen; struct rtable *rt = skb_rtable(skb); __be32 saddr, daddr; struct net *net = dev_net(skb->dev); bool refcounted; int drop_reason; drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; /* * Validate the packet. */ if (!pskb_may_pull(skb, sizeof(struct udphdr))) goto drop; /* No space for header. */ uh = udp_hdr(skb); ulen = ntohs(uh->len); saddr = ip_hdr(skb)->saddr; daddr = ip_hdr(skb)->daddr; if (ulen > skb->len) goto short_packet; if (proto == IPPROTO_UDP) { /* UDP validates ulen. */ if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen)) goto short_packet; uh = udp_hdr(skb); } if (udp4_csum_init(skb, uh, proto)) goto csum_error; sk = inet_steal_sock(net, skb, sizeof(struct udphdr), saddr, uh->source, daddr, uh->dest, &refcounted, udp_ehashfn); if (IS_ERR(sk)) goto no_sk; if (sk) { struct dst_entry *dst = skb_dst(skb); int ret; if (unlikely(rcu_dereference(sk->sk_rx_dst) != dst)) udp_sk_rx_dst_set(sk, dst); ret = udp_unicast_rcv_skb(sk, skb, uh); if (refcounted) sock_put(sk); return ret; } if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST)) return __udp4_lib_mcast_deliver(net, skb, uh, saddr, daddr, udptable, proto); sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable); if (sk) return udp_unicast_rcv_skb(sk, skb, uh); no_sk: if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) goto drop; nf_reset_ct(skb); /* No socket. Drop packet silently, if checksum is wrong */ if (udp_lib_checksum_complete(skb)) goto csum_error; drop_reason = SKB_DROP_REASON_NO_SOCKET; __UDP_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); /* * Hmm. We got an UDP packet to a port to which we * don't wanna listen. Ignore it. */ kfree_skb_reason(skb, drop_reason); return 0; short_packet: drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL; net_dbg_ratelimited("UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n", proto == IPPROTO_UDPLITE ? "Lite" : "", &saddr, ntohs(uh->source), ulen, skb->len, &daddr, ntohs(uh->dest)); goto drop; csum_error: /* * RFC1122: OK. Discards the bad packet silently (as far as * the network is concerned, anyway) as per 4.1.3.4 (MUST). */ drop_reason = SKB_DROP_REASON_UDP_CSUM; net_dbg_ratelimited("UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n", proto == IPPROTO_UDPLITE ? "Lite" : "", &saddr, ntohs(uh->source), &daddr, ntohs(uh->dest), ulen); __UDP_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE); drop: __UDP_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); kfree_skb_reason(skb, drop_reason); return 0; } /* We can only early demux multicast if there is a single matching socket. * If more than one socket found returns NULL */ static struct sock *__udp4_lib_mcast_demux_lookup(struct net *net, __be16 loc_port, __be32 loc_addr, __be16 rmt_port, __be32 rmt_addr, int dif, int sdif) { struct udp_table *udptable = net->ipv4.udp_table; unsigned short hnum = ntohs(loc_port); struct sock *sk, *result; struct udp_hslot *hslot; unsigned int slot; slot = udp_hashfn(net, hnum, udptable->mask); hslot = &udptable->hash[slot]; /* Do not bother scanning a too big list */ if (hslot->count > 10) return NULL; result = NULL; sk_for_each_rcu(sk, &hslot->head) { if (__udp_is_mcast_sock(net, sk, loc_port, loc_addr, rmt_port, rmt_addr, dif, sdif, hnum)) { if (result) return NULL; result = sk; } } return result; } /* For unicast we should only early demux connected sockets or we can * break forwarding setups. The chains here can be long so only check * if the first socket is an exact match and if not move on. */ static struct sock *__udp4_lib_demux_lookup(struct net *net, __be16 loc_port, __be32 loc_addr, __be16 rmt_port, __be32 rmt_addr, int dif, int sdif) { struct udp_table *udptable = net->ipv4.udp_table; INET_ADDR_COOKIE(acookie, rmt_addr, loc_addr); unsigned short hnum = ntohs(loc_port); unsigned int hash2, slot2; struct udp_hslot *hslot2; __portpair ports; struct sock *sk; hash2 = ipv4_portaddr_hash(net, loc_addr, hnum); slot2 = hash2 & udptable->mask; hslot2 = &udptable->hash2[slot2]; ports = INET_COMBINED_PORTS(rmt_port, hnum); udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { if (inet_match(net, sk, acookie, ports, dif, sdif)) return sk; /* Only check first socket in chain */ break; } return NULL; } int udp_v4_early_demux(struct sk_buff *skb) { struct net *net = dev_net(skb->dev); struct in_device *in_dev = NULL; const struct iphdr *iph; const struct udphdr *uh; struct sock *sk = NULL; struct dst_entry *dst; int dif = skb->dev->ifindex; int sdif = inet_sdif(skb); int ours; /* validate the packet */ if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct udphdr))) return 0; iph = ip_hdr(skb); uh = udp_hdr(skb); if (skb->pkt_type == PACKET_MULTICAST) { in_dev = __in_dev_get_rcu(skb->dev); if (!in_dev) return 0; ours = ip_check_mc_rcu(in_dev, iph->daddr, iph->saddr, iph->protocol); if (!ours) return 0; sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr, uh->source, iph->saddr, dif, sdif); } else if (skb->pkt_type == PACKET_HOST) { sk = __udp4_lib_demux_lookup(net, uh->dest, iph->daddr, uh->source, iph->saddr, dif, sdif); } if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt)) return 0; skb->sk = sk; skb->destructor = sock_efree; dst = rcu_dereference(sk->sk_rx_dst); if (dst) dst = dst_check(dst, 0); if (dst) { u32 itag = 0; /* set noref for now. * any place which wants to hold dst has to call * dst_hold_safe() */ skb_dst_set_noref(skb, dst); /* for unconnected multicast sockets we need to validate * the source on each packet */ if (!inet_sk(sk)->inet_daddr && in_dev) return ip_mc_validate_source(skb, iph->daddr, iph->saddr, iph->tos & IPTOS_RT_MASK, skb->dev, in_dev, &itag); } return 0; } int udp_rcv(struct sk_buff *skb) { return __udp4_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP); } void udp_destroy_sock(struct sock *sk) { struct udp_sock *up = udp_sk(sk); bool slow = lock_sock_fast(sk); /* protects from races with udp_abort() */ sock_set_flag(sk, SOCK_DEAD); udp_flush_pending_frames(sk); unlock_sock_fast(sk, slow); if (static_branch_unlikely(&udp_encap_needed_key)) { if (up->encap_type) { void (*encap_destroy)(struct sock *sk); encap_destroy = READ_ONCE(up->encap_destroy); if (encap_destroy) encap_destroy(sk); } if (up->encap_enabled) static_branch_dec(&udp_encap_needed_key); } } /* * Socket option code for UDP */ int udp_lib_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen, int (*push_pending_frames)(struct sock *)) { struct udp_sock *up = udp_sk(sk); int val, valbool; int err = 0; int is_udplite = IS_UDPLITE(sk); if (level == SOL_SOCKET) { err = sk_setsockopt(sk, level, optname, optval, optlen); if (optname == SO_RCVBUF || optname == SO_RCVBUFFORCE) { sockopt_lock_sock(sk); /* paired with READ_ONCE in udp_rmem_release() */ WRITE_ONCE(up->forward_threshold, sk->sk_rcvbuf >> 2); sockopt_release_sock(sk); } return err; } if (optlen < sizeof(int)) return -EINVAL; if (copy_from_sockptr(&val, optval, sizeof(val))) return -EFAULT; valbool = val ? 1 : 0; switch (optname) { case UDP_CORK: if (val != 0) { WRITE_ONCE(up->corkflag, 1); } else { WRITE_ONCE(up->corkflag, 0); lock_sock(sk); push_pending_frames(sk); release_sock(sk); } break; case UDP_ENCAP: switch (val) { case 0: #ifdef CONFIG_XFRM case UDP_ENCAP_ESPINUDP: case UDP_ENCAP_ESPINUDP_NON_IKE: #if IS_ENABLED(CONFIG_IPV6) if (sk->sk_family == AF_INET6) up->encap_rcv = ipv6_stub->xfrm6_udp_encap_rcv; else #endif up->encap_rcv = xfrm4_udp_encap_rcv; #endif fallthrough; case UDP_ENCAP_L2TPINUDP: up->encap_type = val; lock_sock(sk); udp_tunnel_encap_enable(sk->sk_socket); release_sock(sk); break; default: err = -ENOPROTOOPT; break; } break; case UDP_NO_CHECK6_TX: up->no_check6_tx = valbool; break; case UDP_NO_CHECK6_RX: up->no_check6_rx = valbool; break; case UDP_SEGMENT: if (val < 0 || val > USHRT_MAX) return -EINVAL; WRITE_ONCE(up->gso_size, val); break; case UDP_GRO: lock_sock(sk); /* when enabling GRO, accept the related GSO packet type */ if (valbool) udp_tunnel_encap_enable(sk->sk_socket); up->gro_enabled = valbool; up->accept_udp_l4 = valbool; release_sock(sk); break; /* * UDP-Lite's partial checksum coverage (RFC 3828). */ /* The sender sets actual checksum coverage length via this option. * The case coverage > packet length is handled by send module. */ case UDPLITE_SEND_CSCOV: if (!is_udplite) /* Disable the option on UDP sockets */ return -ENOPROTOOPT; if (val != 0 && val < 8) /* Illegal coverage: use default (8) */ val = 8; else if (val > USHRT_MAX) val = USHRT_MAX; up->pcslen = val; up->pcflag |= UDPLITE_SEND_CC; break; /* The receiver specifies a minimum checksum coverage value. To make * sense, this should be set to at least 8 (as done below). If zero is * used, this again means full checksum coverage. */ case UDPLITE_RECV_CSCOV: if (!is_udplite) /* Disable the option on UDP sockets */ return -ENOPROTOOPT; if (val != 0 && val < 8) /* Avoid silly minimal values. */ val = 8; else if (val > USHRT_MAX) val = USHRT_MAX; up->pcrlen = val; up->pcflag |= UDPLITE_RECV_CC; break; default: err = -ENOPROTOOPT; break; } return err; } EXPORT_SYMBOL(udp_lib_setsockopt); int udp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { if (level == SOL_UDP || level == SOL_UDPLITE || level == SOL_SOCKET) return udp_lib_setsockopt(sk, level, optname, optval, optlen, udp_push_pending_frames); return ip_setsockopt(sk, level, optname, optval, optlen); } int udp_lib_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { struct udp_sock *up = udp_sk(sk); int val, len; if (get_user(len, optlen)) return -EFAULT; len = min_t(unsigned int, len, sizeof(int)); if (len < 0) return -EINVAL; switch (optname) { case UDP_CORK: val = READ_ONCE(up->corkflag); break; case UDP_ENCAP: val = up->encap_type; break; case UDP_NO_CHECK6_TX: val = up->no_check6_tx; break; case UDP_NO_CHECK6_RX: val = up->no_check6_rx; break; case UDP_SEGMENT: val = READ_ONCE(up->gso_size); break; case UDP_GRO: val = up->gro_enabled; break; /* The following two cannot be changed on UDP sockets, the return is * always 0 (which corresponds to the full checksum coverage of UDP). */ case UDPLITE_SEND_CSCOV: val = up->pcslen; break; case UDPLITE_RECV_CSCOV: val = up->pcrlen; break; default: return -ENOPROTOOPT; } if (put_user(len, optlen)) return -EFAULT; if (copy_to_user(optval, &val, len)) return -EFAULT; return 0; } EXPORT_SYMBOL(udp_lib_getsockopt); int udp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { if (level == SOL_UDP || level == SOL_UDPLITE) return udp_lib_getsockopt(sk, level, optname, optval, optlen); return ip_getsockopt(sk, level, optname, optval, optlen); } /** * udp_poll - wait for a UDP event. * @file: - file struct * @sock: - socket * @wait: - poll table * * This is same as datagram poll, except for the special case of * blocking sockets. If application is using a blocking fd * and a packet with checksum error is in the queue; * then it could get return from select indicating data available * but then block when reading it. Add special case code * to work around these arguably broken applications. */ __poll_t udp_poll(struct file *file, struct socket *sock, poll_table *wait) { __poll_t mask = datagram_poll(file, sock, wait); struct sock *sk = sock->sk; if (!skb_queue_empty_lockless(&udp_sk(sk)->reader_queue)) mask |= EPOLLIN | EPOLLRDNORM; /* Check for false positives due to checksum errors */ if ((mask & EPOLLRDNORM) && !(file->f_flags & O_NONBLOCK) && !(sk->sk_shutdown & RCV_SHUTDOWN) && first_packet_length(sk) == -1) mask &= ~(EPOLLIN | EPOLLRDNORM); /* psock ingress_msg queue should not contain any bad checksum frames */ if (sk_is_readable(sk)) mask |= EPOLLIN | EPOLLRDNORM; return mask; } EXPORT_SYMBOL(udp_poll); int udp_abort(struct sock *sk, int err) { if (!has_current_bpf_ctx()) lock_sock(sk); /* udp{v6}_destroy_sock() sets it under the sk lock, avoid racing * with close() */ if (sock_flag(sk, SOCK_DEAD)) goto out; sk->sk_err = err; sk_error_report(sk); __udp_disconnect(sk, 0); out: if (!has_current_bpf_ctx()) release_sock(sk); return 0; } EXPORT_SYMBOL_GPL(udp_abort); struct proto udp_prot = { .name = "UDP", .owner = THIS_MODULE, .close = udp_lib_close, .pre_connect = udp_pre_connect, .connect = ip4_datagram_connect, .disconnect = udp_disconnect, .ioctl = udp_ioctl, .init = udp_init_sock, .destroy = udp_destroy_sock, .setsockopt = udp_setsockopt, .getsockopt = udp_getsockopt, .sendmsg = udp_sendmsg, .recvmsg = udp_recvmsg, .splice_eof = udp_splice_eof, .release_cb = ip4_datagram_release_cb, .hash = udp_lib_hash, .unhash = udp_lib_unhash, .rehash = udp_v4_rehash, .get_port = udp_v4_get_port, .put_port = udp_lib_unhash, #ifdef CONFIG_BPF_SYSCALL .psock_update_sk_prot = udp_bpf_update_proto, #endif .memory_allocated = &udp_memory_allocated, .per_cpu_fw_alloc = &udp_memory_per_cpu_fw_alloc, .sysctl_mem = sysctl_udp_mem, .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min), .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min), .obj_size = sizeof(struct udp_sock), .h.udp_table = NULL, .diag_destroy = udp_abort, }; EXPORT_SYMBOL(udp_prot); /* ------------------------------------------------------------------------ */ #ifdef CONFIG_PROC_FS static unsigned short seq_file_family(const struct seq_file *seq); static bool seq_sk_match(struct seq_file *seq, const struct sock *sk) { unsigned short family = seq_file_family(seq); /* AF_UNSPEC is used as a match all */ return ((family == AF_UNSPEC || family == sk->sk_family) && net_eq(sock_net(sk), seq_file_net(seq))); } #ifdef CONFIG_BPF_SYSCALL static const struct seq_operations bpf_iter_udp_seq_ops; #endif static struct udp_table *udp_get_table_seq(struct seq_file *seq, struct net *net) { const struct udp_seq_afinfo *afinfo; #ifdef CONFIG_BPF_SYSCALL if (seq->op == &bpf_iter_udp_seq_ops) return net->ipv4.udp_table; #endif afinfo = pde_data(file_inode(seq->file)); return afinfo->udp_table ? : net->ipv4.udp_table; } static struct sock *udp_get_first(struct seq_file *seq, int start) { struct udp_iter_state *state = seq->private; struct net *net = seq_file_net(seq); struct udp_table *udptable; struct sock *sk; udptable = udp_get_table_seq(seq, net); for (state->bucket = start; state->bucket <= udptable->mask; ++state->bucket) { struct udp_hslot *hslot = &udptable->hash[state->bucket]; if (hlist_empty(&hslot->head)) continue; spin_lock_bh(&hslot->lock); sk_for_each(sk, &hslot->head) { if (seq_sk_match(seq, sk)) goto found; } spin_unlock_bh(&hslot->lock); } sk = NULL; found: return sk; } static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk) { struct udp_iter_state *state = seq->private; struct net *net = seq_file_net(seq); struct udp_table *udptable; do { sk = sk_next(sk); } while (sk && !seq_sk_match(seq, sk)); if (!sk) { udptable = udp_get_table_seq(seq, net); if (state->bucket <= udptable->mask) spin_unlock_bh(&udptable->hash[state->bucket].lock); return udp_get_first(seq, state->bucket + 1); } return sk; } static struct sock *udp_get_idx(struct seq_file *seq, loff_t pos) { struct sock *sk = udp_get_first(seq, 0); if (sk) while (pos && (sk = udp_get_next(seq, sk)) != NULL) --pos; return pos ? NULL : sk; } void *udp_seq_start(struct seq_file *seq, loff_t *pos) { struct udp_iter_state *state = seq->private; state->bucket = MAX_UDP_PORTS; return *pos ? udp_get_idx(seq, *pos-1) : SEQ_START_TOKEN; } EXPORT_SYMBOL(udp_seq_start); void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct sock *sk; if (v == SEQ_START_TOKEN) sk = udp_get_idx(seq, 0); else sk = udp_get_next(seq, v); ++*pos; return sk; } EXPORT_SYMBOL(udp_seq_next); void udp_seq_stop(struct seq_file *seq, void *v) { struct udp_iter_state *state = seq->private; struct udp_table *udptable; udptable = udp_get_table_seq(seq, seq_file_net(seq)); if (state->bucket <= udptable->mask) spin_unlock_bh(&udptable->hash[state->bucket].lock); } EXPORT_SYMBOL(udp_seq_stop); /* ------------------------------------------------------------------------ */ static void udp4_format_sock(struct sock *sp, struct seq_file *f, int bucket) { struct inet_sock *inet = inet_sk(sp); __be32 dest = inet->inet_daddr; __be32 src = inet->inet_rcv_saddr; __u16 destp = ntohs(inet->inet_dport); __u16 srcp = ntohs(inet->inet_sport); seq_printf(f, "%5d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u", bucket, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), udp_rqueue_get(sp), 0, 0L, 0, from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)), 0, sock_i_ino(sp), refcount_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); } int udp4_seq_show(struct seq_file *seq, void *v) { seq_setwidth(seq, 127); if (v == SEQ_START_TOKEN) seq_puts(seq, " sl local_address rem_address st tx_queue " "rx_queue tr tm->when retrnsmt uid timeout " "inode ref pointer drops"); else { struct udp_iter_state *state = seq->private; udp4_format_sock(v, seq, state->bucket); } seq_pad(seq, '\n'); return 0; } #ifdef CONFIG_BPF_SYSCALL struct bpf_iter__udp { __bpf_md_ptr(struct bpf_iter_meta *, meta); __bpf_md_ptr(struct udp_sock *, udp_sk); uid_t uid __aligned(8); int bucket __aligned(8); }; struct bpf_udp_iter_state { struct udp_iter_state state; unsigned int cur_sk; unsigned int end_sk; unsigned int max_sk; int offset; struct sock **batch; bool st_bucket_done; }; static int bpf_iter_udp_realloc_batch(struct bpf_udp_iter_state *iter, unsigned int new_batch_sz); static struct sock *bpf_iter_udp_batch(struct seq_file *seq) { struct bpf_udp_iter_state *iter = seq->private; struct udp_iter_state *state = &iter->state; struct net *net = seq_file_net(seq); struct udp_table *udptable; unsigned int batch_sks = 0; bool resized = false; struct sock *sk; /* The current batch is done, so advance the bucket. */ if (iter->st_bucket_done) { state->bucket++; iter->offset = 0; } udptable = udp_get_table_seq(seq, net); again: /* New batch for the next bucket. * Iterate over the hash table to find a bucket with sockets matching * the iterator attributes, and return the first matching socket from * the bucket. The remaining matched sockets from the bucket are batched * before releasing the bucket lock. This allows BPF programs that are * called in seq_show to acquire the bucket lock if needed. */ iter->cur_sk = 0; iter->end_sk = 0; iter->st_bucket_done = false; batch_sks = 0; for (; state->bucket <= udptable->mask; state->bucket++) { struct udp_hslot *hslot2 = &udptable->hash2[state->bucket]; if (hlist_empty(&hslot2->head)) { iter->offset = 0; continue; } spin_lock_bh(&hslot2->lock); udp_portaddr_for_each_entry(sk, &hslot2->head) { if (seq_sk_match(seq, sk)) { /* Resume from the last iterated socket at the * offset in the bucket before iterator was stopped. */ if (iter->offset) { --iter->offset; continue; } if (iter->end_sk < iter->max_sk) { sock_hold(sk); iter->batch[iter->end_sk++] = sk; } batch_sks++; } } spin_unlock_bh(&hslot2->lock); if (iter->end_sk) break; /* Reset the current bucket's offset before moving to the next bucket. */ iter->offset = 0; } /* All done: no batch made. */ if (!iter->end_sk) return NULL; if (iter->end_sk == batch_sks) { /* Batching is done for the current bucket; return the first * socket to be iterated from the batch. */ iter->st_bucket_done = true; goto done; } if (!resized && !bpf_iter_udp_realloc_batch(iter, batch_sks * 3 / 2)) { resized = true; /* After allocating a larger batch, retry one more time to grab * the whole bucket. */ state->bucket--; goto again; } done: return iter->batch[0]; } static void *bpf_iter_udp_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct bpf_udp_iter_state *iter = seq->private; struct sock *sk; /* Whenever seq_next() is called, the iter->cur_sk is * done with seq_show(), so unref the iter->cur_sk. */ if (iter->cur_sk < iter->end_sk) { sock_put(iter->batch[iter->cur_sk++]); ++iter->offset; } /* After updating iter->cur_sk, check if there are more sockets * available in the current bucket batch. */ if (iter->cur_sk < iter->end_sk) sk = iter->batch[iter->cur_sk]; else /* Prepare a new batch. */ sk = bpf_iter_udp_batch(seq); ++*pos; return sk; } static void *bpf_iter_udp_seq_start(struct seq_file *seq, loff_t *pos) { /* bpf iter does not support lseek, so it always * continue from where it was stop()-ped. */ if (*pos) return bpf_iter_udp_batch(seq); return SEQ_START_TOKEN; } static int udp_prog_seq_show(struct bpf_prog *prog, struct bpf_iter_meta *meta, struct udp_sock *udp_sk, uid_t uid, int bucket) { struct bpf_iter__udp ctx; meta->seq_num--; /* skip SEQ_START_TOKEN */ ctx.meta = meta; ctx.udp_sk = udp_sk; ctx.uid = uid; ctx.bucket = bucket; return bpf_iter_run_prog(prog, &ctx); } static int bpf_iter_udp_seq_show(struct seq_file *seq, void *v) { struct udp_iter_state *state = seq->private; struct bpf_iter_meta meta; struct bpf_prog *prog; struct sock *sk = v; uid_t uid; int ret; if (v == SEQ_START_TOKEN) return 0; lock_sock(sk); if (unlikely(sk_unhashed(sk))) { ret = SEQ_SKIP; goto unlock; } uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)); meta.seq = seq; prog = bpf_iter_get_info(&meta, false); ret = udp_prog_seq_show(prog, &meta, v, uid, state->bucket); unlock: release_sock(sk); return ret; } static void bpf_iter_udp_put_batch(struct bpf_udp_iter_state *iter) { while (iter->cur_sk < iter->end_sk) sock_put(iter->batch[iter->cur_sk++]); } static void bpf_iter_udp_seq_stop(struct seq_file *seq, void *v) { struct bpf_udp_iter_state *iter = seq->private; struct bpf_iter_meta meta; struct bpf_prog *prog; if (!v) { meta.seq = seq; prog = bpf_iter_get_info(&meta, true); if (prog) (void)udp_prog_seq_show(prog, &meta, v, 0, 0); } if (iter->cur_sk < iter->end_sk) { bpf_iter_udp_put_batch(iter); iter->st_bucket_done = false; } } static const struct seq_operations bpf_iter_udp_seq_ops = { .start = bpf_iter_udp_seq_start, .next = bpf_iter_udp_seq_next, .stop = bpf_iter_udp_seq_stop, .show = bpf_iter_udp_seq_show, }; #endif static unsigned short seq_file_family(const struct seq_file *seq) { const struct udp_seq_afinfo *afinfo; #ifdef CONFIG_BPF_SYSCALL /* BPF iterator: bpf programs to filter sockets. */ if (seq->op == &bpf_iter_udp_seq_ops) return AF_UNSPEC; #endif /* Proc fs iterator */ afinfo = pde_data(file_inode(seq->file)); return afinfo->family; } const struct seq_operations udp_seq_ops = { .start = udp_seq_start, .next = udp_seq_next, .stop = udp_seq_stop, .show = udp4_seq_show, }; EXPORT_SYMBOL(udp_seq_ops); static struct udp_seq_afinfo udp4_seq_afinfo = { .family = AF_INET, .udp_table = NULL, }; static int __net_init udp4_proc_init_net(struct net *net) { if (!proc_create_net_data("udp", 0444, net->proc_net, &udp_seq_ops, sizeof(struct udp_iter_state), &udp4_seq_afinfo)) return -ENOMEM; return 0; } static void __net_exit udp4_proc_exit_net(struct net *net) { remove_proc_entry("udp", net->proc_net); } static struct pernet_operations udp4_net_ops = { .init = udp4_proc_init_net, .exit = udp4_proc_exit_net, }; int __init udp4_proc_init(void) { return register_pernet_subsys(&udp4_net_ops); } void udp4_proc_exit(void) { unregister_pernet_subsys(&udp4_net_ops); } #endif /* CONFIG_PROC_FS */ static __initdata unsigned long uhash_entries; static int __init set_uhash_entries(char *str) { ssize_t ret; if (!str) return 0; ret = kstrtoul(str, 0, &uhash_entries); if (ret) return 0; if (uhash_entries && uhash_entries < UDP_HTABLE_SIZE_MIN) uhash_entries = UDP_HTABLE_SIZE_MIN; return 1; } __setup("uhash_entries=", set_uhash_entries); void __init udp_table_init(struct udp_table *table, const char *name) { unsigned int i; table->hash = alloc_large_system_hash(name, 2 * sizeof(struct udp_hslot), uhash_entries, 21, /* one slot per 2 MB */ 0, &table->log, &table->mask, UDP_HTABLE_SIZE_MIN, UDP_HTABLE_SIZE_MAX); table->hash2 = table->hash + (table->mask + 1); for (i = 0; i <= table->mask; i++) { INIT_HLIST_HEAD(&table->hash[i].head); table->hash[i].count = 0; spin_lock_init(&table->hash[i].lock); } for (i = 0; i <= table->mask; i++) { INIT_HLIST_HEAD(&table->hash2[i].head); table->hash2[i].count = 0; spin_lock_init(&table->hash2[i].lock); } } u32 udp_flow_hashrnd(void) { static u32 hashrnd __read_mostly; net_get_random_once(&hashrnd, sizeof(hashrnd)); return hashrnd; } EXPORT_SYMBOL(udp_flow_hashrnd); static void __net_init udp_sysctl_init(struct net *net) { net->ipv4.sysctl_udp_rmem_min = PAGE_SIZE; net->ipv4.sysctl_udp_wmem_min = PAGE_SIZE; #ifdef CONFIG_NET_L3_MASTER_DEV net->ipv4.sysctl_udp_l3mdev_accept = 0; #endif } static struct udp_table __net_init *udp_pernet_table_alloc(unsigned int hash_entries) { struct udp_table *udptable; int i; udptable = kmalloc(sizeof(*udptable), GFP_KERNEL); if (!udptable) goto out; udptable->hash = vmalloc_huge(hash_entries * 2 * sizeof(struct udp_hslot), GFP_KERNEL_ACCOUNT); if (!udptable->hash) goto free_table; udptable->hash2 = udptable->hash + hash_entries; udptable->mask = hash_entries - 1; udptable->log = ilog2(hash_entries); for (i = 0; i < hash_entries; i++) { INIT_HLIST_HEAD(&udptable->hash[i].head); udptable->hash[i].count = 0; spin_lock_init(&udptable->hash[i].lock); INIT_HLIST_HEAD(&udptable->hash2[i].head); udptable->hash2[i].count = 0; spin_lock_init(&udptable->hash2[i].lock); } return udptable; free_table: kfree(udptable); out: return NULL; } static void __net_exit udp_pernet_table_free(struct net *net) { struct udp_table *udptable = net->ipv4.udp_table; if (udptable == &udp_table) return; kvfree(udptable->hash); kfree(udptable); } static void __net_init udp_set_table(struct net *net) { struct udp_table *udptable; unsigned int hash_entries; struct net *old_net; if (net_eq(net, &init_net)) goto fallback; old_net = current->nsproxy->net_ns; hash_entries = READ_ONCE(old_net->ipv4.sysctl_udp_child_hash_entries); if (!hash_entries) goto fallback; /* Set min to keep the bitmap on stack in udp_lib_get_port() */ if (hash_entries < UDP_HTABLE_SIZE_MIN_PERNET) hash_entries = UDP_HTABLE_SIZE_MIN_PERNET; else hash_entries = roundup_pow_of_two(hash_entries); udptable = udp_pernet_table_alloc(hash_entries); if (udptable) { net->ipv4.udp_table = udptable; } else { pr_warn("Failed to allocate UDP hash table (entries: %u) " "for a netns, fallback to the global one\n", hash_entries); fallback: net->ipv4.udp_table = &udp_table; } } static int __net_init udp_pernet_init(struct net *net) { udp_sysctl_init(net); udp_set_table(net); return 0; } static void __net_exit udp_pernet_exit(struct net *net) { udp_pernet_table_free(net); } static struct pernet_operations __net_initdata udp_sysctl_ops = { .init = udp_pernet_init, .exit = udp_pernet_exit, }; #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) DEFINE_BPF_ITER_FUNC(udp, struct bpf_iter_meta *meta, struct udp_sock *udp_sk, uid_t uid, int bucket) static int bpf_iter_udp_realloc_batch(struct bpf_udp_iter_state *iter, unsigned int new_batch_sz) { struct sock **new_batch; new_batch = kvmalloc_array(new_batch_sz, sizeof(*new_batch), GFP_USER | __GFP_NOWARN); if (!new_batch) return -ENOMEM; bpf_iter_udp_put_batch(iter); kvfree(iter->batch); iter->batch = new_batch; iter->max_sk = new_batch_sz; return 0; } #define INIT_BATCH_SZ 16 static int bpf_iter_init_udp(void *priv_data, struct bpf_iter_aux_info *aux) { struct bpf_udp_iter_state *iter = priv_data; int ret; ret = bpf_iter_init_seq_net(priv_data, aux); if (ret) return ret; ret = bpf_iter_udp_realloc_batch(iter, INIT_BATCH_SZ); if (ret) bpf_iter_fini_seq_net(priv_data); return ret; } static void bpf_iter_fini_udp(void *priv_data) { struct bpf_udp_iter_state *iter = priv_data; bpf_iter_fini_seq_net(priv_data); kvfree(iter->batch); } static const struct bpf_iter_seq_info udp_seq_info = { .seq_ops = &bpf_iter_udp_seq_ops, .init_seq_private = bpf_iter_init_udp, .fini_seq_private = bpf_iter_fini_udp, .seq_priv_size = sizeof(struct bpf_udp_iter_state), }; static struct bpf_iter_reg udp_reg_info = { .target = "udp", .ctx_arg_info_size = 1, .ctx_arg_info = { { offsetof(struct bpf_iter__udp, udp_sk), PTR_TO_BTF_ID_OR_NULL | PTR_TRUSTED }, }, .seq_info = &udp_seq_info, }; static void __init bpf_iter_register(void) { udp_reg_info.ctx_arg_info[0].btf_id = btf_sock_ids[BTF_SOCK_TYPE_UDP]; if (bpf_iter_reg_target(&udp_reg_info)) pr_warn("Warning: could not register bpf iterator udp\n"); } #endif void __init udp_init(void) { unsigned long limit; unsigned int i; udp_table_init(&udp_table, "UDP"); limit = nr_free_buffer_pages() / 8; limit = max(limit, 128UL); sysctl_udp_mem[0] = limit / 4 * 3; sysctl_udp_mem[1] = limit; sysctl_udp_mem[2] = sysctl_udp_mem[0] * 2; /* 16 spinlocks per cpu */ udp_busylocks_log = ilog2(nr_cpu_ids) + 4; udp_busylocks = kmalloc(sizeof(spinlock_t) << udp_busylocks_log, GFP_KERNEL); if (!udp_busylocks) panic("UDP: failed to alloc udp_busylocks\n"); for (i = 0; i < (1U << udp_busylocks_log); i++) spin_lock_init(udp_busylocks + i); if (register_pernet_subsys(&udp_sysctl_ops)) panic("UDP: failed to init sysctl parameters.\n"); #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) bpf_iter_register(); #endif }
linux-master
net/ipv4/udp.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * The Internet Protocol (IP) module. * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * Donald Becker, <[email protected]> * Alan Cox, <[email protected]> * Richard Underwood * Stefan Becker, <[email protected]> * Jorge Cwik, <[email protected]> * Arnt Gulbrandsen, <[email protected]> * * Fixes: * Alan Cox : Commented a couple of minor bits of surplus code * Alan Cox : Undefining IP_FORWARD doesn't include the code * (just stops a compiler warning). * Alan Cox : Frames with >=MAX_ROUTE record routes, strict routes or loose routes * are junked rather than corrupting things. * Alan Cox : Frames to bad broadcast subnets are dumped * We used to process them non broadcast and * boy could that cause havoc. * Alan Cox : ip_forward sets the free flag on the * new frame it queues. Still crap because * it copies the frame but at least it * doesn't eat memory too. * Alan Cox : Generic queue code and memory fixes. * Fred Van Kempen : IP fragment support (borrowed from NET2E) * Gerhard Koerting: Forward fragmented frames correctly. * Gerhard Koerting: Fixes to my fix of the above 8-). * Gerhard Koerting: IP interface addressing fix. * Linus Torvalds : More robustness checks * Alan Cox : Even more checks: Still not as robust as it ought to be * Alan Cox : Save IP header pointer for later * Alan Cox : ip option setting * Alan Cox : Use ip_tos/ip_ttl settings * Alan Cox : Fragmentation bogosity removed * (Thanks to [email protected]) * Dmitry Gorodchanin : Send of a raw packet crash fix. * Alan Cox : Silly ip bug when an overlength * fragment turns up. Now frees the * queue. * Linus Torvalds/ : Memory leakage on fragmentation * Alan Cox : handling. * Gerhard Koerting: Forwarding uses IP priority hints * Teemu Rantanen : Fragment problems. * Alan Cox : General cleanup, comments and reformat * Alan Cox : SNMP statistics * Alan Cox : BSD address rule semantics. Also see * UDP as there is a nasty checksum issue * if you do things the wrong way. * Alan Cox : Always defrag, moved IP_FORWARD to the config.in file * Alan Cox : IP options adjust sk->priority. * Pedro Roque : Fix mtu/length error in ip_forward. * Alan Cox : Avoid ip_chk_addr when possible. * Richard Underwood : IP multicasting. * Alan Cox : Cleaned up multicast handlers. * Alan Cox : RAW sockets demultiplex in the BSD style. * Gunther Mayer : Fix the SNMP reporting typo * Alan Cox : Always in group 224.0.0.1 * Pauline Middelink : Fast ip_checksum update when forwarding * Masquerading support. * Alan Cox : Multicast loopback error for 224.0.0.1 * Alan Cox : IP_MULTICAST_LOOP option. * Alan Cox : Use notifiers. * Bjorn Ekwall : Removed ip_csum (from slhc.c too) * Bjorn Ekwall : Moved ip_fast_csum to ip.h (inline!) * Stefan Becker : Send out ICMP HOST REDIRECT * Arnt Gulbrandsen : ip_build_xmit * Alan Cox : Per socket routing cache * Alan Cox : Fixed routing cache, added header cache. * Alan Cox : Loopback didn't work right in original ip_build_xmit - fixed it. * Alan Cox : Only send ICMP_REDIRECT if src/dest are the same net. * Alan Cox : Incoming IP option handling. * Alan Cox : Set saddr on raw output frames as per BSD. * Alan Cox : Stopped broadcast source route explosions. * Alan Cox : Can disable source routing * Takeshi Sone : Masquerading didn't work. * Dave Bonn,Alan Cox : Faster IP forwarding whenever possible. * Alan Cox : Memory leaks, tramples, misc debugging. * Alan Cox : Fixed multicast (by popular demand 8)) * Alan Cox : Fixed forwarding (by even more popular demand 8)) * Alan Cox : Fixed SNMP statistics [I think] * Gerhard Koerting : IP fragmentation forwarding fix * Alan Cox : Device lock against page fault. * Alan Cox : IP_HDRINCL facility. * Werner Almesberger : Zero fragment bug * Alan Cox : RAW IP frame length bug * Alan Cox : Outgoing firewall on build_xmit * A.N.Kuznetsov : IP_OPTIONS support throughout the kernel * Alan Cox : Multicast routing hooks * Jos Vos : Do accounting *before* call_in_firewall * Willy Konynenberg : Transparent proxying support * * To Fix: * IP fragmentation wants rewriting cleanly. The RFC815 algorithm is much more efficient * and could be made very efficient with the addition of some virtual memory hacks to permit * the allocation of a buffer that can then be 'grown' by twiddling page tables. * Output fragmentation wants updating along with the buffer management to use a single * interleaved copy algorithm so that fragmenting has a one copy overhead. Actual packet * output should probably do its own fragmentation at the UDP/RAW layer. TCP shouldn't cause * fragmentation anyway. */ #define pr_fmt(fmt) "IPv4: " fmt #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/string.h> #include <linux/errno.h> #include <linux/slab.h> #include <linux/net.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/in.h> #include <linux/inet.h> #include <linux/inetdevice.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/indirect_call_wrapper.h> #include <net/snmp.h> #include <net/ip.h> #include <net/protocol.h> #include <net/route.h> #include <linux/skbuff.h> #include <net/sock.h> #include <net/arp.h> #include <net/icmp.h> #include <net/raw.h> #include <net/checksum.h> #include <net/inet_ecn.h> #include <linux/netfilter_ipv4.h> #include <net/xfrm.h> #include <linux/mroute.h> #include <linux/netlink.h> #include <net/dst_metadata.h> /* * Process Router Attention IP option (RFC 2113) */ bool ip_call_ra_chain(struct sk_buff *skb) { struct ip_ra_chain *ra; u8 protocol = ip_hdr(skb)->protocol; struct sock *last = NULL; struct net_device *dev = skb->dev; struct net *net = dev_net(dev); for (ra = rcu_dereference(net->ipv4.ra_chain); ra; ra = rcu_dereference(ra->next)) { struct sock *sk = ra->sk; /* If socket is bound to an interface, only report * the packet if it came from that interface. */ if (sk && inet_sk(sk)->inet_num == protocol && (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dev->ifindex)) { if (ip_is_fragment(ip_hdr(skb))) { if (ip_defrag(net, skb, IP_DEFRAG_CALL_RA_CHAIN)) return true; } if (last) { struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) raw_rcv(last, skb2); } last = sk; } } if (last) { raw_rcv(last, skb); return true; } return false; } INDIRECT_CALLABLE_DECLARE(int udp_rcv(struct sk_buff *)); INDIRECT_CALLABLE_DECLARE(int tcp_v4_rcv(struct sk_buff *)); void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int protocol) { const struct net_protocol *ipprot; int raw, ret; resubmit: raw = raw_local_deliver(skb, protocol); ipprot = rcu_dereference(inet_protos[protocol]); if (ipprot) { if (!ipprot->no_policy) { if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { kfree_skb_reason(skb, SKB_DROP_REASON_XFRM_POLICY); return; } nf_reset_ct(skb); } ret = INDIRECT_CALL_2(ipprot->handler, tcp_v4_rcv, udp_rcv, skb); if (ret < 0) { protocol = -ret; goto resubmit; } __IP_INC_STATS(net, IPSTATS_MIB_INDELIVERS); } else { if (!raw) { if (xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { __IP_INC_STATS(net, IPSTATS_MIB_INUNKNOWNPROTOS); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PROT_UNREACH, 0); } kfree_skb_reason(skb, SKB_DROP_REASON_IP_NOPROTO); } else { __IP_INC_STATS(net, IPSTATS_MIB_INDELIVERS); consume_skb(skb); } } } static int ip_local_deliver_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { skb_clear_delivery_time(skb); __skb_pull(skb, skb_network_header_len(skb)); rcu_read_lock(); ip_protocol_deliver_rcu(net, skb, ip_hdr(skb)->protocol); rcu_read_unlock(); return 0; } /* * Deliver IP Packets to the higher protocol layers. */ int ip_local_deliver(struct sk_buff *skb) { /* * Reassemble IP fragments. */ struct net *net = dev_net(skb->dev); if (ip_is_fragment(ip_hdr(skb))) { if (ip_defrag(net, skb, IP_DEFRAG_LOCAL_DELIVER)) return 0; } return NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_IN, net, NULL, skb, skb->dev, NULL, ip_local_deliver_finish); } EXPORT_SYMBOL(ip_local_deliver); static inline bool ip_rcv_options(struct sk_buff *skb, struct net_device *dev) { struct ip_options *opt; const struct iphdr *iph; /* It looks as overkill, because not all IP options require packet mangling. But it is the easiest for now, especially taking into account that combination of IP options and running sniffer is extremely rare condition. --ANK (980813) */ if (skb_cow(skb, skb_headroom(skb))) { __IP_INC_STATS(dev_net(dev), IPSTATS_MIB_INDISCARDS); goto drop; } iph = ip_hdr(skb); opt = &(IPCB(skb)->opt); opt->optlen = iph->ihl*4 - sizeof(struct iphdr); if (ip_options_compile(dev_net(dev), opt, skb)) { __IP_INC_STATS(dev_net(dev), IPSTATS_MIB_INHDRERRORS); goto drop; } if (unlikely(opt->srr)) { struct in_device *in_dev = __in_dev_get_rcu(dev); if (in_dev) { if (!IN_DEV_SOURCE_ROUTE(in_dev)) { if (IN_DEV_LOG_MARTIANS(in_dev)) net_info_ratelimited("source route option %pI4 -> %pI4\n", &iph->saddr, &iph->daddr); goto drop; } } if (ip_options_rcv_srr(skb, dev)) goto drop; } return false; drop: return true; } static bool ip_can_use_hint(const struct sk_buff *skb, const struct iphdr *iph, const struct sk_buff *hint) { return hint && !skb_dst(skb) && ip_hdr(hint)->daddr == iph->daddr && ip_hdr(hint)->tos == iph->tos; } int tcp_v4_early_demux(struct sk_buff *skb); int udp_v4_early_demux(struct sk_buff *skb); static int ip_rcv_finish_core(struct net *net, struct sock *sk, struct sk_buff *skb, struct net_device *dev, const struct sk_buff *hint) { const struct iphdr *iph = ip_hdr(skb); int err, drop_reason; struct rtable *rt; drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; if (ip_can_use_hint(skb, iph, hint)) { err = ip_route_use_hint(skb, iph->daddr, iph->saddr, iph->tos, dev, hint); if (unlikely(err)) goto drop_error; } if (READ_ONCE(net->ipv4.sysctl_ip_early_demux) && !skb_dst(skb) && !skb->sk && !ip_is_fragment(iph)) { switch (iph->protocol) { case IPPROTO_TCP: if (READ_ONCE(net->ipv4.sysctl_tcp_early_demux)) { tcp_v4_early_demux(skb); /* must reload iph, skb->head might have changed */ iph = ip_hdr(skb); } break; case IPPROTO_UDP: if (READ_ONCE(net->ipv4.sysctl_udp_early_demux)) { err = udp_v4_early_demux(skb); if (unlikely(err)) goto drop_error; /* must reload iph, skb->head might have changed */ iph = ip_hdr(skb); } break; } } /* * Initialise the virtual path cache for the packet. It describes * how the packet travels inside Linux networking. */ if (!skb_valid_dst(skb)) { err = ip_route_input_noref(skb, iph->daddr, iph->saddr, iph->tos, dev); if (unlikely(err)) goto drop_error; } else { struct in_device *in_dev = __in_dev_get_rcu(dev); if (in_dev && IN_DEV_ORCONF(in_dev, NOPOLICY)) IPCB(skb)->flags |= IPSKB_NOPOLICY; } #ifdef CONFIG_IP_ROUTE_CLASSID if (unlikely(skb_dst(skb)->tclassid)) { struct ip_rt_acct *st = this_cpu_ptr(ip_rt_acct); u32 idx = skb_dst(skb)->tclassid; st[idx&0xFF].o_packets++; st[idx&0xFF].o_bytes += skb->len; st[(idx>>16)&0xFF].i_packets++; st[(idx>>16)&0xFF].i_bytes += skb->len; } #endif if (iph->ihl > 5 && ip_rcv_options(skb, dev)) goto drop; rt = skb_rtable(skb); if (rt->rt_type == RTN_MULTICAST) { __IP_UPD_PO_STATS(net, IPSTATS_MIB_INMCAST, skb->len); } else if (rt->rt_type == RTN_BROADCAST) { __IP_UPD_PO_STATS(net, IPSTATS_MIB_INBCAST, skb->len); } else if (skb->pkt_type == PACKET_BROADCAST || skb->pkt_type == PACKET_MULTICAST) { struct in_device *in_dev = __in_dev_get_rcu(dev); /* RFC 1122 3.3.6: * * When a host sends a datagram to a link-layer broadcast * address, the IP destination address MUST be a legal IP * broadcast or IP multicast address. * * A host SHOULD silently discard a datagram that is received * via a link-layer broadcast (see Section 2.4) but does not * specify an IP multicast or broadcast destination address. * * This doesn't explicitly say L2 *broadcast*, but broadcast is * in a way a form of multicast and the most common use case for * this is 802.11 protecting against cross-station spoofing (the * so-called "hole-196" attack) so do it for both. */ if (in_dev && IN_DEV_ORCONF(in_dev, DROP_UNICAST_IN_L2_MULTICAST)) { drop_reason = SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST; goto drop; } } return NET_RX_SUCCESS; drop: kfree_skb_reason(skb, drop_reason); return NET_RX_DROP; drop_error: if (err == -EXDEV) { drop_reason = SKB_DROP_REASON_IP_RPFILTER; __NET_INC_STATS(net, LINUX_MIB_IPRPFILTER); } goto drop; } static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { struct net_device *dev = skb->dev; int ret; /* if ingress device is enslaved to an L3 master device pass the * skb to its handler for processing */ skb = l3mdev_ip_rcv(skb); if (!skb) return NET_RX_SUCCESS; ret = ip_rcv_finish_core(net, sk, skb, dev, NULL); if (ret != NET_RX_DROP) ret = dst_input(skb); return ret; } /* * Main IP Receive routine. */ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) { const struct iphdr *iph; int drop_reason; u32 len; /* When the interface is in promisc. mode, drop all the crap * that it receives, do not try to analyse it. */ if (skb->pkt_type == PACKET_OTHERHOST) { dev_core_stats_rx_otherhost_dropped_inc(skb->dev); drop_reason = SKB_DROP_REASON_OTHERHOST; goto drop; } __IP_UPD_PO_STATS(net, IPSTATS_MIB_IN, skb->len); skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) { __IP_INC_STATS(net, IPSTATS_MIB_INDISCARDS); goto out; } drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; if (!pskb_may_pull(skb, sizeof(struct iphdr))) goto inhdr_error; iph = ip_hdr(skb); /* * RFC1122: 3.2.1.2 MUST silently discard any IP frame that fails the checksum. * * Is the datagram acceptable? * * 1. Length at least the size of an ip header * 2. Version of 4 * 3. Checksums correctly. [Speed optimisation for later, skip loopback checksums] * 4. Doesn't have a bogus length */ if (iph->ihl < 5 || iph->version != 4) goto inhdr_error; BUILD_BUG_ON(IPSTATS_MIB_ECT1PKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_ECT_1); BUILD_BUG_ON(IPSTATS_MIB_ECT0PKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_ECT_0); BUILD_BUG_ON(IPSTATS_MIB_CEPKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_CE); __IP_ADD_STATS(net, IPSTATS_MIB_NOECTPKTS + (iph->tos & INET_ECN_MASK), max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); if (!pskb_may_pull(skb, iph->ihl*4)) goto inhdr_error; iph = ip_hdr(skb); if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) goto csum_error; len = iph_totlen(skb, iph); if (skb->len < len) { drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL; __IP_INC_STATS(net, IPSTATS_MIB_INTRUNCATEDPKTS); goto drop; } else if (len < (iph->ihl*4)) goto inhdr_error; /* Our transport medium may have padded the buffer out. Now we know it * is IP we can trim to the true length of the frame. * Note this now means skb->len holds ntohs(iph->tot_len). */ if (pskb_trim_rcsum(skb, len)) { __IP_INC_STATS(net, IPSTATS_MIB_INDISCARDS); goto drop; } iph = ip_hdr(skb); skb->transport_header = skb->network_header + iph->ihl*4; /* Remove any debris in the socket control block */ memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); IPCB(skb)->iif = skb->skb_iif; /* Must drop socket now because of tproxy. */ if (!skb_sk_is_prefetched(skb)) skb_orphan(skb); return skb; csum_error: drop_reason = SKB_DROP_REASON_IP_CSUM; __IP_INC_STATS(net, IPSTATS_MIB_CSUMERRORS); inhdr_error: if (drop_reason == SKB_DROP_REASON_NOT_SPECIFIED) drop_reason = SKB_DROP_REASON_IP_INHDR; __IP_INC_STATS(net, IPSTATS_MIB_INHDRERRORS); drop: kfree_skb_reason(skb, drop_reason); out: return NULL; } /* * IP receive entry point */ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct net *net = dev_net(dev); skb = ip_rcv_core(skb, net); if (skb == NULL) return NET_RX_DROP; return NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING, net, NULL, skb, dev, NULL, ip_rcv_finish); } static void ip_sublist_rcv_finish(struct list_head *head) { struct sk_buff *skb, *next; list_for_each_entry_safe(skb, next, head, list) { skb_list_del_init(skb); dst_input(skb); } } static struct sk_buff *ip_extract_route_hint(const struct net *net, struct sk_buff *skb, int rt_type) { if (fib4_has_custom_rules(net) || rt_type == RTN_BROADCAST || IPCB(skb)->flags & IPSKB_MULTIPATH) return NULL; return skb; } static void ip_list_rcv_finish(struct net *net, struct sock *sk, struct list_head *head) { struct sk_buff *skb, *next, *hint = NULL; struct dst_entry *curr_dst = NULL; struct list_head sublist; INIT_LIST_HEAD(&sublist); list_for_each_entry_safe(skb, next, head, list) { struct net_device *dev = skb->dev; struct dst_entry *dst; skb_list_del_init(skb); /* if ingress device is enslaved to an L3 master device pass the * skb to its handler for processing */ skb = l3mdev_ip_rcv(skb); if (!skb) continue; if (ip_rcv_finish_core(net, sk, skb, dev, hint) == NET_RX_DROP) continue; dst = skb_dst(skb); if (curr_dst != dst) { hint = ip_extract_route_hint(net, skb, ((struct rtable *)dst)->rt_type); /* dispatch old sublist */ if (!list_empty(&sublist)) ip_sublist_rcv_finish(&sublist); /* start new sublist */ INIT_LIST_HEAD(&sublist); curr_dst = dst; } list_add_tail(&skb->list, &sublist); } /* dispatch final sublist */ ip_sublist_rcv_finish(&sublist); } static void ip_sublist_rcv(struct list_head *head, struct net_device *dev, struct net *net) { NF_HOOK_LIST(NFPROTO_IPV4, NF_INET_PRE_ROUTING, net, NULL, head, dev, NULL, ip_rcv_finish); ip_list_rcv_finish(net, NULL, head); } /* Receive a list of IP packets */ void ip_list_rcv(struct list_head *head, struct packet_type *pt, struct net_device *orig_dev) { struct net_device *curr_dev = NULL; struct net *curr_net = NULL; struct sk_buff *skb, *next; struct list_head sublist; INIT_LIST_HEAD(&sublist); list_for_each_entry_safe(skb, next, head, list) { struct net_device *dev = skb->dev; struct net *net = dev_net(dev); skb_list_del_init(skb); skb = ip_rcv_core(skb, net); if (skb == NULL) continue; if (curr_dev != dev || curr_net != net) { /* dispatch old sublist */ if (!list_empty(&sublist)) ip_sublist_rcv(&sublist, curr_dev, curr_net); /* start new sublist */ INIT_LIST_HEAD(&sublist); curr_dev = dev; curr_net = net; } list_add_tail(&skb->list, &sublist); } /* dispatch final sublist */ if (!list_empty(&sublist)) ip_sublist_rcv(&sublist, curr_dev, curr_net); }
linux-master
net/ipv4/ip_input.c
// SPDX-License-Identifier: GPL-2.0-or-later /* DataCenter TCP (DCTCP) congestion control. * * http://simula.stanford.edu/~alizade/Site/DCTCP.html * * This is an implementation of DCTCP over Reno, an enhancement to the * TCP congestion control algorithm designed for data centers. DCTCP * leverages Explicit Congestion Notification (ECN) in the network to * provide multi-bit feedback to the end hosts. DCTCP's goal is to meet * the following three data center transport requirements: * * - High burst tolerance (incast due to partition/aggregate) * - Low latency (short flows, queries) * - High throughput (continuous data updates, large file transfers) * with commodity shallow buffered switches * * The algorithm is described in detail in the following two papers: * * 1) Mohammad Alizadeh, Albert Greenberg, David A. Maltz, Jitendra Padhye, * Parveen Patel, Balaji Prabhakar, Sudipta Sengupta, and Murari Sridharan: * "Data Center TCP (DCTCP)", Data Center Networks session * Proc. ACM SIGCOMM, New Delhi, 2010. * http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf * * 2) Mohammad Alizadeh, Adel Javanmard, and Balaji Prabhakar: * "Analysis of DCTCP: Stability, Convergence, and Fairness" * Proc. ACM SIGMETRICS, San Jose, 2011. * http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp_analysis-full.pdf * * Initial prototype from Abdul Kabbani, Masato Yasuda and Mohammad Alizadeh. * * Authors: * * Daniel Borkmann <[email protected]> * Florian Westphal <[email protected]> * Glenn Judd <[email protected]> */ #include <linux/btf.h> #include <linux/btf_ids.h> #include <linux/module.h> #include <linux/mm.h> #include <net/tcp.h> #include <linux/inet_diag.h> #include "tcp_dctcp.h" #define DCTCP_MAX_ALPHA 1024U struct dctcp { u32 old_delivered; u32 old_delivered_ce; u32 prior_rcv_nxt; u32 dctcp_alpha; u32 next_seq; u32 ce_state; u32 loss_cwnd; struct tcp_plb_state plb; }; static unsigned int dctcp_shift_g __read_mostly = 4; /* g = 1/2^4 */ module_param(dctcp_shift_g, uint, 0644); MODULE_PARM_DESC(dctcp_shift_g, "parameter g for updating dctcp_alpha"); static unsigned int dctcp_alpha_on_init __read_mostly = DCTCP_MAX_ALPHA; module_param(dctcp_alpha_on_init, uint, 0644); MODULE_PARM_DESC(dctcp_alpha_on_init, "parameter for initial alpha value"); static struct tcp_congestion_ops dctcp_reno; static void dctcp_reset(const struct tcp_sock *tp, struct dctcp *ca) { ca->next_seq = tp->snd_nxt; ca->old_delivered = tp->delivered; ca->old_delivered_ce = tp->delivered_ce; } __bpf_kfunc static void dctcp_init(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); if ((tp->ecn_flags & TCP_ECN_OK) || (sk->sk_state == TCP_LISTEN || sk->sk_state == TCP_CLOSE)) { struct dctcp *ca = inet_csk_ca(sk); ca->prior_rcv_nxt = tp->rcv_nxt; ca->dctcp_alpha = min(dctcp_alpha_on_init, DCTCP_MAX_ALPHA); ca->loss_cwnd = 0; ca->ce_state = 0; dctcp_reset(tp, ca); tcp_plb_init(sk, &ca->plb); return; } /* No ECN support? Fall back to Reno. Also need to clear * ECT from sk since it is set during 3WHS for DCTCP. */ inet_csk(sk)->icsk_ca_ops = &dctcp_reno; INET_ECN_dontxmit(sk); } __bpf_kfunc static u32 dctcp_ssthresh(struct sock *sk) { struct dctcp *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); ca->loss_cwnd = tcp_snd_cwnd(tp); return max(tcp_snd_cwnd(tp) - ((tcp_snd_cwnd(tp) * ca->dctcp_alpha) >> 11U), 2U); } __bpf_kfunc static void dctcp_update_alpha(struct sock *sk, u32 flags) { const struct tcp_sock *tp = tcp_sk(sk); struct dctcp *ca = inet_csk_ca(sk); /* Expired RTT */ if (!before(tp->snd_una, ca->next_seq)) { u32 delivered = tp->delivered - ca->old_delivered; u32 delivered_ce = tp->delivered_ce - ca->old_delivered_ce; u32 alpha = ca->dctcp_alpha; u32 ce_ratio = 0; if (delivered > 0) { /* dctcp_alpha keeps EWMA of fraction of ECN marked * packets. Because of EWMA smoothing, PLB reaction can * be slow so we use ce_ratio which is an instantaneous * measure of congestion. ce_ratio is the fraction of * ECN marked packets in the previous RTT. */ if (delivered_ce > 0) ce_ratio = (delivered_ce << TCP_PLB_SCALE) / delivered; tcp_plb_update_state(sk, &ca->plb, (int)ce_ratio); tcp_plb_check_rehash(sk, &ca->plb); } /* alpha = (1 - g) * alpha + g * F */ alpha -= min_not_zero(alpha, alpha >> dctcp_shift_g); if (delivered_ce) { /* If dctcp_shift_g == 1, a 32bit value would overflow * after 8 M packets. */ delivered_ce <<= (10 - dctcp_shift_g); delivered_ce /= max(1U, delivered); alpha = min(alpha + delivered_ce, DCTCP_MAX_ALPHA); } /* dctcp_alpha can be read from dctcp_get_info() without * synchro, so we ask compiler to not use dctcp_alpha * as a temporary variable in prior operations. */ WRITE_ONCE(ca->dctcp_alpha, alpha); dctcp_reset(tp, ca); } } static void dctcp_react_to_loss(struct sock *sk) { struct dctcp *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); ca->loss_cwnd = tcp_snd_cwnd(tp); tp->snd_ssthresh = max(tcp_snd_cwnd(tp) >> 1U, 2U); } __bpf_kfunc static void dctcp_state(struct sock *sk, u8 new_state) { if (new_state == TCP_CA_Recovery && new_state != inet_csk(sk)->icsk_ca_state) dctcp_react_to_loss(sk); /* We handle RTO in dctcp_cwnd_event to ensure that we perform only * one loss-adjustment per RTT. */ } __bpf_kfunc static void dctcp_cwnd_event(struct sock *sk, enum tcp_ca_event ev) { struct dctcp *ca = inet_csk_ca(sk); switch (ev) { case CA_EVENT_ECN_IS_CE: case CA_EVENT_ECN_NO_CE: dctcp_ece_ack_update(sk, ev, &ca->prior_rcv_nxt, &ca->ce_state); break; case CA_EVENT_LOSS: tcp_plb_update_state_upon_rto(sk, &ca->plb); dctcp_react_to_loss(sk); break; case CA_EVENT_TX_START: tcp_plb_check_rehash(sk, &ca->plb); /* Maybe rehash when inflight is 0 */ break; default: /* Don't care for the rest. */ break; } } static size_t dctcp_get_info(struct sock *sk, u32 ext, int *attr, union tcp_cc_info *info) { const struct dctcp *ca = inet_csk_ca(sk); const struct tcp_sock *tp = tcp_sk(sk); /* Fill it also in case of VEGASINFO due to req struct limits. * We can still correctly retrieve it later. */ if (ext & (1 << (INET_DIAG_DCTCPINFO - 1)) || ext & (1 << (INET_DIAG_VEGASINFO - 1))) { memset(&info->dctcp, 0, sizeof(info->dctcp)); if (inet_csk(sk)->icsk_ca_ops != &dctcp_reno) { info->dctcp.dctcp_enabled = 1; info->dctcp.dctcp_ce_state = (u16) ca->ce_state; info->dctcp.dctcp_alpha = ca->dctcp_alpha; info->dctcp.dctcp_ab_ecn = tp->mss_cache * (tp->delivered_ce - ca->old_delivered_ce); info->dctcp.dctcp_ab_tot = tp->mss_cache * (tp->delivered - ca->old_delivered); } *attr = INET_DIAG_DCTCPINFO; return sizeof(info->dctcp); } return 0; } __bpf_kfunc static u32 dctcp_cwnd_undo(struct sock *sk) { const struct dctcp *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); return max(tcp_snd_cwnd(tp), ca->loss_cwnd); } static struct tcp_congestion_ops dctcp __read_mostly = { .init = dctcp_init, .in_ack_event = dctcp_update_alpha, .cwnd_event = dctcp_cwnd_event, .ssthresh = dctcp_ssthresh, .cong_avoid = tcp_reno_cong_avoid, .undo_cwnd = dctcp_cwnd_undo, .set_state = dctcp_state, .get_info = dctcp_get_info, .flags = TCP_CONG_NEEDS_ECN, .owner = THIS_MODULE, .name = "dctcp", }; static struct tcp_congestion_ops dctcp_reno __read_mostly = { .ssthresh = tcp_reno_ssthresh, .cong_avoid = tcp_reno_cong_avoid, .undo_cwnd = tcp_reno_undo_cwnd, .get_info = dctcp_get_info, .owner = THIS_MODULE, .name = "dctcp-reno", }; BTF_SET8_START(tcp_dctcp_check_kfunc_ids) #ifdef CONFIG_X86 #ifdef CONFIG_DYNAMIC_FTRACE BTF_ID_FLAGS(func, dctcp_init) BTF_ID_FLAGS(func, dctcp_update_alpha) BTF_ID_FLAGS(func, dctcp_cwnd_event) BTF_ID_FLAGS(func, dctcp_ssthresh) BTF_ID_FLAGS(func, dctcp_cwnd_undo) BTF_ID_FLAGS(func, dctcp_state) #endif #endif BTF_SET8_END(tcp_dctcp_check_kfunc_ids) static const struct btf_kfunc_id_set tcp_dctcp_kfunc_set = { .owner = THIS_MODULE, .set = &tcp_dctcp_check_kfunc_ids, }; static int __init dctcp_register(void) { int ret; BUILD_BUG_ON(sizeof(struct dctcp) > ICSK_CA_PRIV_SIZE); ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS, &tcp_dctcp_kfunc_set); if (ret < 0) return ret; return tcp_register_congestion_control(&dctcp); } static void __exit dctcp_unregister(void) { tcp_unregister_congestion_control(&dctcp); } module_init(dctcp_register); module_exit(dctcp_unregister); MODULE_AUTHOR("Daniel Borkmann <[email protected]>"); MODULE_AUTHOR("Florian Westphal <[email protected]>"); MODULE_AUTHOR("Glenn Judd <[email protected]>"); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("DataCenter TCP (DCTCP)");
linux-master
net/ipv4/tcp_dctcp.c
// SPDX-License-Identifier: GPL-2.0-only /* * TCP Illinois congestion control. * Home page: * http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html * * The algorithm is described in: * "TCP-Illinois: A Loss and Delay-Based Congestion Control Algorithm * for High-Speed Networks" * http://tamerbasar.csl.illinois.edu/LiuBasarSrikantPerfEvalArtJun2008.pdf * * Implemented from description in paper and ns-2 simulation. * Copyright (C) 2007 Stephen Hemminger <[email protected]> */ #include <linux/module.h> #include <linux/skbuff.h> #include <linux/inet_diag.h> #include <asm/div64.h> #include <net/tcp.h> #define ALPHA_SHIFT 7 #define ALPHA_SCALE (1u<<ALPHA_SHIFT) #define ALPHA_MIN ((3*ALPHA_SCALE)/10) /* ~0.3 */ #define ALPHA_MAX (10*ALPHA_SCALE) /* 10.0 */ #define ALPHA_BASE ALPHA_SCALE /* 1.0 */ #define RTT_MAX (U32_MAX / ALPHA_MAX) /* 3.3 secs */ #define BETA_SHIFT 6 #define BETA_SCALE (1u<<BETA_SHIFT) #define BETA_MIN (BETA_SCALE/8) /* 0.125 */ #define BETA_MAX (BETA_SCALE/2) /* 0.5 */ #define BETA_BASE BETA_MAX static int win_thresh __read_mostly = 15; module_param(win_thresh, int, 0); MODULE_PARM_DESC(win_thresh, "Window threshold for starting adaptive sizing"); static int theta __read_mostly = 5; module_param(theta, int, 0); MODULE_PARM_DESC(theta, "# of fast RTT's before full growth"); /* TCP Illinois Parameters */ struct illinois { u64 sum_rtt; /* sum of rtt's measured within last rtt */ u16 cnt_rtt; /* # of rtts measured within last rtt */ u32 base_rtt; /* min of all rtt in usec */ u32 max_rtt; /* max of all rtt in usec */ u32 end_seq; /* right edge of current RTT */ u32 alpha; /* Additive increase */ u32 beta; /* Muliplicative decrease */ u16 acked; /* # packets acked by current ACK */ u8 rtt_above; /* average rtt has gone above threshold */ u8 rtt_low; /* # of rtts measurements below threshold */ }; static void rtt_reset(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct illinois *ca = inet_csk_ca(sk); ca->end_seq = tp->snd_nxt; ca->cnt_rtt = 0; ca->sum_rtt = 0; /* TODO: age max_rtt? */ } static void tcp_illinois_init(struct sock *sk) { struct illinois *ca = inet_csk_ca(sk); ca->alpha = ALPHA_MAX; ca->beta = BETA_BASE; ca->base_rtt = 0x7fffffff; ca->max_rtt = 0; ca->acked = 0; ca->rtt_low = 0; ca->rtt_above = 0; rtt_reset(sk); } /* Measure RTT for each ack. */ static void tcp_illinois_acked(struct sock *sk, const struct ack_sample *sample) { struct illinois *ca = inet_csk_ca(sk); s32 rtt_us = sample->rtt_us; ca->acked = sample->pkts_acked; /* dup ack, no rtt sample */ if (rtt_us < 0) return; /* ignore bogus values, this prevents wraparound in alpha math */ if (rtt_us > RTT_MAX) rtt_us = RTT_MAX; /* keep track of minimum RTT seen so far */ if (ca->base_rtt > rtt_us) ca->base_rtt = rtt_us; /* and max */ if (ca->max_rtt < rtt_us) ca->max_rtt = rtt_us; ++ca->cnt_rtt; ca->sum_rtt += rtt_us; } /* Maximum queuing delay */ static inline u32 max_delay(const struct illinois *ca) { return ca->max_rtt - ca->base_rtt; } /* Average queuing delay */ static inline u32 avg_delay(const struct illinois *ca) { u64 t = ca->sum_rtt; do_div(t, ca->cnt_rtt); return t - ca->base_rtt; } /* * Compute value of alpha used for additive increase. * If small window then use 1.0, equivalent to Reno. * * For larger windows, adjust based on average delay. * A. If average delay is at minimum (we are uncongested), * then use large alpha (10.0) to increase faster. * B. If average delay is at maximum (getting congested) * then use small alpha (0.3) * * The result is a convex window growth curve. */ static u32 alpha(struct illinois *ca, u32 da, u32 dm) { u32 d1 = dm / 100; /* Low threshold */ if (da <= d1) { /* If never got out of low delay zone, then use max */ if (!ca->rtt_above) return ALPHA_MAX; /* Wait for 5 good RTT's before allowing alpha to go alpha max. * This prevents one good RTT from causing sudden window increase. */ if (++ca->rtt_low < theta) return ca->alpha; ca->rtt_low = 0; ca->rtt_above = 0; return ALPHA_MAX; } ca->rtt_above = 1; /* * Based on: * * (dm - d1) amin amax * k1 = ------------------- * amax - amin * * (dm - d1) amin * k2 = ---------------- - d1 * amax - amin * * k1 * alpha = ---------- * k2 + da */ dm -= d1; da -= d1; return (dm * ALPHA_MAX) / (dm + (da * (ALPHA_MAX - ALPHA_MIN)) / ALPHA_MIN); } /* * Beta used for multiplicative decrease. * For small window sizes returns same value as Reno (0.5) * * If delay is small (10% of max) then beta = 1/8 * If delay is up to 80% of max then beta = 1/2 * In between is a linear function */ static u32 beta(u32 da, u32 dm) { u32 d2, d3; d2 = dm / 10; if (da <= d2) return BETA_MIN; d3 = (8 * dm) / 10; if (da >= d3 || d3 <= d2) return BETA_MAX; /* * Based on: * * bmin d3 - bmax d2 * k3 = ------------------- * d3 - d2 * * bmax - bmin * k4 = ------------- * d3 - d2 * * b = k3 + k4 da */ return (BETA_MIN * d3 - BETA_MAX * d2 + (BETA_MAX - BETA_MIN) * da) / (d3 - d2); } /* Update alpha and beta values once per RTT */ static void update_params(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct illinois *ca = inet_csk_ca(sk); if (tcp_snd_cwnd(tp) < win_thresh) { ca->alpha = ALPHA_BASE; ca->beta = BETA_BASE; } else if (ca->cnt_rtt > 0) { u32 dm = max_delay(ca); u32 da = avg_delay(ca); ca->alpha = alpha(ca, da, dm); ca->beta = beta(da, dm); } rtt_reset(sk); } /* * In case of loss, reset to default values */ static void tcp_illinois_state(struct sock *sk, u8 new_state) { struct illinois *ca = inet_csk_ca(sk); if (new_state == TCP_CA_Loss) { ca->alpha = ALPHA_BASE; ca->beta = BETA_BASE; ca->rtt_low = 0; ca->rtt_above = 0; rtt_reset(sk); } } /* * Increase window in response to successful acknowledgment. */ static void tcp_illinois_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct illinois *ca = inet_csk_ca(sk); if (after(ack, ca->end_seq)) update_params(sk); /* RFC2861 only increase cwnd if fully utilized */ if (!tcp_is_cwnd_limited(sk)) return; /* In slow start */ if (tcp_in_slow_start(tp)) tcp_slow_start(tp, acked); else { u32 delta; /* snd_cwnd_cnt is # of packets since last cwnd increment */ tp->snd_cwnd_cnt += ca->acked; ca->acked = 1; /* This is close approximation of: * tp->snd_cwnd += alpha/tp->snd_cwnd */ delta = (tp->snd_cwnd_cnt * ca->alpha) >> ALPHA_SHIFT; if (delta >= tcp_snd_cwnd(tp)) { tcp_snd_cwnd_set(tp, min(tcp_snd_cwnd(tp) + delta / tcp_snd_cwnd(tp), (u32)tp->snd_cwnd_clamp)); tp->snd_cwnd_cnt = 0; } } } static u32 tcp_illinois_ssthresh(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct illinois *ca = inet_csk_ca(sk); u32 decr; /* Multiplicative decrease */ decr = (tcp_snd_cwnd(tp) * ca->beta) >> BETA_SHIFT; return max(tcp_snd_cwnd(tp) - decr, 2U); } /* Extract info for Tcp socket info provided via netlink. */ static size_t tcp_illinois_info(struct sock *sk, u32 ext, int *attr, union tcp_cc_info *info) { const struct illinois *ca = inet_csk_ca(sk); if (ext & (1 << (INET_DIAG_VEGASINFO - 1))) { info->vegas.tcpv_enabled = 1; info->vegas.tcpv_rttcnt = ca->cnt_rtt; info->vegas.tcpv_minrtt = ca->base_rtt; info->vegas.tcpv_rtt = 0; if (info->vegas.tcpv_rttcnt > 0) { u64 t = ca->sum_rtt; do_div(t, info->vegas.tcpv_rttcnt); info->vegas.tcpv_rtt = t; } *attr = INET_DIAG_VEGASINFO; return sizeof(struct tcpvegas_info); } return 0; } static struct tcp_congestion_ops tcp_illinois __read_mostly = { .init = tcp_illinois_init, .ssthresh = tcp_illinois_ssthresh, .undo_cwnd = tcp_reno_undo_cwnd, .cong_avoid = tcp_illinois_cong_avoid, .set_state = tcp_illinois_state, .get_info = tcp_illinois_info, .pkts_acked = tcp_illinois_acked, .owner = THIS_MODULE, .name = "illinois", }; static int __init tcp_illinois_register(void) { BUILD_BUG_ON(sizeof(struct illinois) > ICSK_CA_PRIV_SIZE); return tcp_register_congestion_control(&tcp_illinois); } static void __exit tcp_illinois_unregister(void) { tcp_unregister_congestion_control(&tcp_illinois); } module_init(tcp_illinois_register); module_exit(tcp_illinois_unregister); MODULE_AUTHOR("Stephen Hemminger, Shao Liu"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("TCP Illinois"); MODULE_VERSION("1.0");
linux-master
net/ipv4/tcp_illinois.c
// SPDX-License-Identifier: GPL-2.0-only #define pr_fmt(fmt) "IPsec: " fmt #include <crypto/algapi.h> #include <crypto/hash.h> #include <linux/err.h> #include <linux/module.h> #include <linux/slab.h> #include <net/ip.h> #include <net/xfrm.h> #include <net/ah.h> #include <linux/crypto.h> #include <linux/pfkeyv2.h> #include <linux/scatterlist.h> #include <net/icmp.h> #include <net/protocol.h> struct ah_skb_cb { struct xfrm_skb_cb xfrm; void *tmp; }; #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, unsigned int size) { unsigned int len; len = size + crypto_ahash_digestsize(ahash) + (crypto_ahash_alignmask(ahash) & ~(crypto_tfm_ctx_alignment() - 1)); len = ALIGN(len, crypto_tfm_ctx_alignment()); len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); len = ALIGN(len, __alignof__(struct scatterlist)); len += sizeof(struct scatterlist) * nfrags; return kmalloc(len, GFP_ATOMIC); } static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset) { return tmp + offset; } static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, unsigned int offset) { return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); } static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, u8 *icv) { struct ahash_request *req; req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), crypto_tfm_ctx_alignment()); ahash_request_set_tfm(req, ahash); return req; } static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, struct ahash_request *req) { return (void *)ALIGN((unsigned long)(req + 1) + crypto_ahash_reqsize(ahash), __alignof__(struct scatterlist)); } /* Clear mutable options and find final destination to substitute * into IP header for icv calculation. Options are already checked * for validity, so paranoia is not required. */ static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr) { unsigned char *optptr = (unsigned char *)(iph+1); int l = iph->ihl*4 - sizeof(struct iphdr); int optlen; while (l > 0) { switch (*optptr) { case IPOPT_END: return 0; case IPOPT_NOOP: l--; optptr++; continue; } optlen = optptr[1]; if (optlen<2 || optlen>l) return -EINVAL; switch (*optptr) { case IPOPT_SEC: case 0x85: /* Some "Extended Security" crap. */ case IPOPT_CIPSO: case IPOPT_RA: case 0x80|21: /* RFC1770 */ break; case IPOPT_LSRR: case IPOPT_SSRR: if (optlen < 6) return -EINVAL; memcpy(daddr, optptr+optlen-4, 4); fallthrough; default: memset(optptr, 0, optlen); } l -= optlen; optptr += optlen; } return 0; } static void ah_output_done(void *data, int err) { u8 *icv; struct iphdr *iph; struct sk_buff *skb = data; struct xfrm_state *x = skb_dst(skb)->xfrm; struct ah_data *ahp = x->data; struct iphdr *top_iph = ip_hdr(skb); struct ip_auth_hdr *ah = ip_auth_hdr(skb); int ihl = ip_hdrlen(skb); iph = AH_SKB_CB(skb)->tmp; icv = ah_tmp_icv(ahp->ahash, iph, ihl); memcpy(ah->auth_data, icv, ahp->icv_trunc_len); top_iph->tos = iph->tos; top_iph->ttl = iph->ttl; top_iph->frag_off = iph->frag_off; if (top_iph->ihl != 5) { top_iph->daddr = iph->daddr; memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); } kfree(AH_SKB_CB(skb)->tmp); xfrm_output_resume(skb->sk, skb, err); } static int ah_output(struct xfrm_state *x, struct sk_buff *skb) { int err; int nfrags; int ihl; u8 *icv; struct sk_buff *trailer; struct crypto_ahash *ahash; struct ahash_request *req; struct scatterlist *sg; struct iphdr *iph, *top_iph; struct ip_auth_hdr *ah; struct ah_data *ahp; int seqhi_len = 0; __be32 *seqhi; int sglists = 0; struct scatterlist *seqhisg; ahp = x->data; ahash = ahp->ahash; if ((err = skb_cow_data(skb, 0, &trailer)) < 0) goto out; nfrags = err; skb_push(skb, -skb_network_offset(skb)); ah = ip_auth_hdr(skb); ihl = ip_hdrlen(skb); if (x->props.flags & XFRM_STATE_ESN) { sglists = 1; seqhi_len = sizeof(*seqhi); } err = -ENOMEM; iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + seqhi_len); if (!iph) goto out; seqhi = (__be32 *)((char *)iph + ihl); icv = ah_tmp_icv(ahash, seqhi, seqhi_len); req = ah_tmp_req(ahash, icv); sg = ah_req_sg(ahash, req); seqhisg = sg + nfrags; memset(ah->auth_data, 0, ahp->icv_trunc_len); top_iph = ip_hdr(skb); iph->tos = top_iph->tos; iph->ttl = top_iph->ttl; iph->frag_off = top_iph->frag_off; if (top_iph->ihl != 5) { iph->daddr = top_iph->daddr; memcpy(iph+1, top_iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); err = ip_clear_mutable_options(top_iph, &top_iph->daddr); if (err) goto out_free; } ah->nexthdr = *skb_mac_header(skb); *skb_mac_header(skb) = IPPROTO_AH; top_iph->tos = 0; top_iph->tot_len = htons(skb->len); top_iph->frag_off = 0; top_iph->ttl = 0; top_iph->check = 0; if (x->props.flags & XFRM_STATE_ALIGN4) ah->hdrlen = (XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; else ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; ah->reserved = 0; ah->spi = x->id.spi; ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); sg_init_table(sg, nfrags + sglists); err = skb_to_sgvec_nomark(skb, sg, 0, skb->len); if (unlikely(err < 0)) goto out_free; if (x->props.flags & XFRM_STATE_ESN) { /* Attach seqhi sg right after packet payload */ *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); sg_set_buf(seqhisg, seqhi, seqhi_len); } ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len); ahash_request_set_callback(req, 0, ah_output_done, skb); AH_SKB_CB(skb)->tmp = iph; err = crypto_ahash_digest(req); if (err) { if (err == -EINPROGRESS) goto out; if (err == -ENOSPC) err = NET_XMIT_DROP; goto out_free; } memcpy(ah->auth_data, icv, ahp->icv_trunc_len); top_iph->tos = iph->tos; top_iph->ttl = iph->ttl; top_iph->frag_off = iph->frag_off; if (top_iph->ihl != 5) { top_iph->daddr = iph->daddr; memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); } out_free: kfree(iph); out: return err; } static void ah_input_done(void *data, int err) { u8 *auth_data; u8 *icv; struct iphdr *work_iph; struct sk_buff *skb = data; struct xfrm_state *x = xfrm_input_state(skb); struct ah_data *ahp = x->data; struct ip_auth_hdr *ah = ip_auth_hdr(skb); int ihl = ip_hdrlen(skb); int ah_hlen = (ah->hdrlen + 2) << 2; if (err) goto out; work_iph = AH_SKB_CB(skb)->tmp; auth_data = ah_tmp_auth(work_iph, ihl); icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len); err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0; if (err) goto out; err = ah->nexthdr; skb->network_header += ah_hlen; memcpy(skb_network_header(skb), work_iph, ihl); __skb_pull(skb, ah_hlen + ihl); if (x->props.mode == XFRM_MODE_TUNNEL) skb_reset_transport_header(skb); else skb_set_transport_header(skb, -ihl); out: kfree(AH_SKB_CB(skb)->tmp); xfrm_input_resume(skb, err); } static int ah_input(struct xfrm_state *x, struct sk_buff *skb) { int ah_hlen; int ihl; int nexthdr; int nfrags; u8 *auth_data; u8 *icv; struct sk_buff *trailer; struct crypto_ahash *ahash; struct ahash_request *req; struct scatterlist *sg; struct iphdr *iph, *work_iph; struct ip_auth_hdr *ah; struct ah_data *ahp; int err = -ENOMEM; int seqhi_len = 0; __be32 *seqhi; int sglists = 0; struct scatterlist *seqhisg; if (!pskb_may_pull(skb, sizeof(*ah))) goto out; ah = (struct ip_auth_hdr *)skb->data; ahp = x->data; ahash = ahp->ahash; nexthdr = ah->nexthdr; ah_hlen = (ah->hdrlen + 2) << 2; if (x->props.flags & XFRM_STATE_ALIGN4) { if (ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_full_len) && ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len)) goto out; } else { if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) goto out; } if (!pskb_may_pull(skb, ah_hlen)) goto out; /* We are going to _remove_ AH header to keep sockets happy, * so... Later this can change. */ if (skb_unclone(skb, GFP_ATOMIC)) goto out; skb->ip_summed = CHECKSUM_NONE; if ((err = skb_cow_data(skb, 0, &trailer)) < 0) goto out; nfrags = err; ah = (struct ip_auth_hdr *)skb->data; iph = ip_hdr(skb); ihl = ip_hdrlen(skb); if (x->props.flags & XFRM_STATE_ESN) { sglists = 1; seqhi_len = sizeof(*seqhi); } work_iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + ahp->icv_trunc_len + seqhi_len); if (!work_iph) { err = -ENOMEM; goto out; } seqhi = (__be32 *)((char *)work_iph + ihl); auth_data = ah_tmp_auth(seqhi, seqhi_len); icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len); req = ah_tmp_req(ahash, icv); sg = ah_req_sg(ahash, req); seqhisg = sg + nfrags; memcpy(work_iph, iph, ihl); memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); memset(ah->auth_data, 0, ahp->icv_trunc_len); iph->ttl = 0; iph->tos = 0; iph->frag_off = 0; iph->check = 0; if (ihl > sizeof(*iph)) { __be32 dummy; err = ip_clear_mutable_options(iph, &dummy); if (err) goto out_free; } skb_push(skb, ihl); sg_init_table(sg, nfrags + sglists); err = skb_to_sgvec_nomark(skb, sg, 0, skb->len); if (unlikely(err < 0)) goto out_free; if (x->props.flags & XFRM_STATE_ESN) { /* Attach seqhi sg right after packet payload */ *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; sg_set_buf(seqhisg, seqhi, seqhi_len); } ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len); ahash_request_set_callback(req, 0, ah_input_done, skb); AH_SKB_CB(skb)->tmp = work_iph; err = crypto_ahash_digest(req); if (err) { if (err == -EINPROGRESS) goto out; goto out_free; } err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0; if (err) goto out_free; skb->network_header += ah_hlen; memcpy(skb_network_header(skb), work_iph, ihl); __skb_pull(skb, ah_hlen + ihl); if (x->props.mode == XFRM_MODE_TUNNEL) skb_reset_transport_header(skb); else skb_set_transport_header(skb, -ihl); err = nexthdr; out_free: kfree (work_iph); out: return err; } static int ah4_err(struct sk_buff *skb, u32 info) { struct net *net = dev_net(skb->dev); const struct iphdr *iph = (const struct iphdr *)skb->data; struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); struct xfrm_state *x; switch (icmp_hdr(skb)->type) { case ICMP_DEST_UNREACH: if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) return 0; break; case ICMP_REDIRECT: break; default: return 0; } x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET); if (!x) return 0; if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) ipv4_update_pmtu(skb, net, info, 0, IPPROTO_AH); else ipv4_redirect(skb, net, 0, IPPROTO_AH); xfrm_state_put(x); return 0; } static int ah_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack) { struct ah_data *ahp = NULL; struct xfrm_algo_desc *aalg_desc; struct crypto_ahash *ahash; if (!x->aalg) { NL_SET_ERR_MSG(extack, "AH requires a state with an AUTH algorithm"); goto error; } if (x->encap) { NL_SET_ERR_MSG(extack, "AH is not compatible with encapsulation"); goto error; } ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); if (!ahp) return -ENOMEM; ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); if (IS_ERR(ahash)) { NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); goto error; } ahp->ahash = ahash; if (crypto_ahash_setkey(ahash, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8)) { NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); goto error; } /* * Lookup the algorithm description maintained by xfrm_algo, * verify crypto transform properties, and store information * we need for AH processing. This lookup cannot fail here * after a successful crypto_alloc_ahash(). */ aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); BUG_ON(!aalg_desc); if (aalg_desc->uinfo.auth.icv_fullbits/8 != crypto_ahash_digestsize(ahash)) { NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); goto error; } ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; if (x->props.flags & XFRM_STATE_ALIGN4) x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) + ahp->icv_trunc_len); else x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + ahp->icv_trunc_len); if (x->props.mode == XFRM_MODE_TUNNEL) x->props.header_len += sizeof(struct iphdr); x->data = ahp; return 0; error: if (ahp) { crypto_free_ahash(ahp->ahash); kfree(ahp); } return -EINVAL; } static void ah_destroy(struct xfrm_state *x) { struct ah_data *ahp = x->data; if (!ahp) return; crypto_free_ahash(ahp->ahash); kfree(ahp); } static int ah4_rcv_cb(struct sk_buff *skb, int err) { return 0; } static const struct xfrm_type ah_type = { .owner = THIS_MODULE, .proto = IPPROTO_AH, .flags = XFRM_TYPE_REPLAY_PROT, .init_state = ah_init_state, .destructor = ah_destroy, .input = ah_input, .output = ah_output }; static struct xfrm4_protocol ah4_protocol = { .handler = xfrm4_rcv, .input_handler = xfrm_input, .cb_handler = ah4_rcv_cb, .err_handler = ah4_err, .priority = 0, }; static int __init ah4_init(void) { if (xfrm_register_type(&ah_type, AF_INET) < 0) { pr_info("%s: can't add xfrm type\n", __func__); return -EAGAIN; } if (xfrm4_protocol_register(&ah4_protocol, IPPROTO_AH) < 0) { pr_info("%s: can't add protocol\n", __func__); xfrm_unregister_type(&ah_type, AF_INET); return -EAGAIN; } return 0; } static void __exit ah4_fini(void) { if (xfrm4_protocol_deregister(&ah4_protocol, IPPROTO_AH) < 0) pr_info("%s: can't remove protocol\n", __func__); xfrm_unregister_type(&ah_type, AF_INET); } module_init(ah4_init); module_exit(ah4_fini); MODULE_LICENSE("GPL"); MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_AH);
linux-master
net/ipv4/ah4.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * udp_diag.c Module for monitoring UDP transport protocols sockets. * * Authors: Pavel Emelyanov, <[email protected]> */ #include <linux/module.h> #include <linux/inet_diag.h> #include <linux/udp.h> #include <net/udp.h> #include <net/udplite.h> #include <linux/sock_diag.h> static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *req, struct nlattr *bc, bool net_admin) { if (!inet_diag_bc_sk(bc, sk)) return 0; return inet_sk_diag_fill(sk, NULL, skb, cb, req, NLM_F_MULTI, net_admin); } static int udp_dump_one(struct udp_table *tbl, struct netlink_callback *cb, const struct inet_diag_req_v2 *req) { struct sk_buff *in_skb = cb->skb; int err; struct sock *sk = NULL; struct sk_buff *rep; struct net *net = sock_net(in_skb->sk); rcu_read_lock(); if (req->sdiag_family == AF_INET) /* src and dst are swapped for historical reasons */ sk = __udp4_lib_lookup(net, req->id.idiag_src[0], req->id.idiag_sport, req->id.idiag_dst[0], req->id.idiag_dport, req->id.idiag_if, 0, tbl, NULL); #if IS_ENABLED(CONFIG_IPV6) else if (req->sdiag_family == AF_INET6) sk = __udp6_lib_lookup(net, (struct in6_addr *)req->id.idiag_src, req->id.idiag_sport, (struct in6_addr *)req->id.idiag_dst, req->id.idiag_dport, req->id.idiag_if, 0, tbl, NULL); #endif if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) sk = NULL; rcu_read_unlock(); err = -ENOENT; if (!sk) goto out_nosk; err = sock_diag_check_cookie(sk, req->id.idiag_cookie); if (err) goto out; err = -ENOMEM; rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) + inet_diag_msg_attrs_size() + nla_total_size(sizeof(struct inet_diag_meminfo)) + 64, GFP_KERNEL); if (!rep) goto out; err = inet_sk_diag_fill(sk, NULL, rep, cb, req, 0, netlink_net_capable(in_skb, CAP_NET_ADMIN)); if (err < 0) { WARN_ON(err == -EMSGSIZE); kfree_skb(rep); goto out; } err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid); out: if (sk) sock_put(sk); out_nosk: return err; } static void udp_dump(struct udp_table *table, struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *r) { bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); struct net *net = sock_net(skb->sk); struct inet_diag_dump_data *cb_data; int num, s_num, slot, s_slot; struct nlattr *bc; cb_data = cb->data; bc = cb_data->inet_diag_nla_bc; s_slot = cb->args[0]; num = s_num = cb->args[1]; for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) { struct udp_hslot *hslot = &table->hash[slot]; struct sock *sk; num = 0; if (hlist_empty(&hslot->head)) continue; spin_lock_bh(&hslot->lock); sk_for_each(sk, &hslot->head) { struct inet_sock *inet = inet_sk(sk); if (!net_eq(sock_net(sk), net)) continue; if (num < s_num) goto next; if (!(r->idiag_states & (1 << sk->sk_state))) goto next; if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family) goto next; if (r->id.idiag_sport != inet->inet_sport && r->id.idiag_sport) goto next; if (r->id.idiag_dport != inet->inet_dport && r->id.idiag_dport) goto next; if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) { spin_unlock_bh(&hslot->lock); goto done; } next: num++; } spin_unlock_bh(&hslot->lock); } done: cb->args[0] = slot; cb->args[1] = num; } static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *r) { udp_dump(sock_net(cb->skb->sk)->ipv4.udp_table, skb, cb, r); } static int udp_diag_dump_one(struct netlink_callback *cb, const struct inet_diag_req_v2 *req) { return udp_dump_one(sock_net(cb->skb->sk)->ipv4.udp_table, cb, req); } static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, void *info) { r->idiag_rqueue = udp_rqueue_get(sk); r->idiag_wqueue = sk_wmem_alloc_get(sk); } #ifdef CONFIG_INET_DIAG_DESTROY static int __udp_diag_destroy(struct sk_buff *in_skb, const struct inet_diag_req_v2 *req, struct udp_table *tbl) { struct net *net = sock_net(in_skb->sk); struct sock *sk; int err; rcu_read_lock(); if (req->sdiag_family == AF_INET) sk = __udp4_lib_lookup(net, req->id.idiag_dst[0], req->id.idiag_dport, req->id.idiag_src[0], req->id.idiag_sport, req->id.idiag_if, 0, tbl, NULL); #if IS_ENABLED(CONFIG_IPV6) else if (req->sdiag_family == AF_INET6) { if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) && ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src)) sk = __udp4_lib_lookup(net, req->id.idiag_dst[3], req->id.idiag_dport, req->id.idiag_src[3], req->id.idiag_sport, req->id.idiag_if, 0, tbl, NULL); else sk = __udp6_lib_lookup(net, (struct in6_addr *)req->id.idiag_dst, req->id.idiag_dport, (struct in6_addr *)req->id.idiag_src, req->id.idiag_sport, req->id.idiag_if, 0, tbl, NULL); } #endif else { rcu_read_unlock(); return -EINVAL; } if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) sk = NULL; rcu_read_unlock(); if (!sk) return -ENOENT; if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) { sock_put(sk); return -ENOENT; } err = sock_diag_destroy(sk, ECONNABORTED); sock_put(sk); return err; } static int udp_diag_destroy(struct sk_buff *in_skb, const struct inet_diag_req_v2 *req) { return __udp_diag_destroy(in_skb, req, sock_net(in_skb->sk)->ipv4.udp_table); } static int udplite_diag_destroy(struct sk_buff *in_skb, const struct inet_diag_req_v2 *req) { return __udp_diag_destroy(in_skb, req, &udplite_table); } #endif static const struct inet_diag_handler udp_diag_handler = { .dump = udp_diag_dump, .dump_one = udp_diag_dump_one, .idiag_get_info = udp_diag_get_info, .idiag_type = IPPROTO_UDP, .idiag_info_size = 0, #ifdef CONFIG_INET_DIAG_DESTROY .destroy = udp_diag_destroy, #endif }; static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *r) { udp_dump(&udplite_table, skb, cb, r); } static int udplite_diag_dump_one(struct netlink_callback *cb, const struct inet_diag_req_v2 *req) { return udp_dump_one(&udplite_table, cb, req); } static const struct inet_diag_handler udplite_diag_handler = { .dump = udplite_diag_dump, .dump_one = udplite_diag_dump_one, .idiag_get_info = udp_diag_get_info, .idiag_type = IPPROTO_UDPLITE, .idiag_info_size = 0, #ifdef CONFIG_INET_DIAG_DESTROY .destroy = udplite_diag_destroy, #endif }; static int __init udp_diag_init(void) { int err; err = inet_diag_register(&udp_diag_handler); if (err) goto out; err = inet_diag_register(&udplite_diag_handler); if (err) goto out_lite; out: return err; out_lite: inet_diag_unregister(&udp_diag_handler); goto out; } static void __exit udp_diag_exit(void) { inet_diag_unregister(&udplite_diag_handler); inet_diag_unregister(&udp_diag_handler); } module_init(udp_diag_init); module_exit(udp_diag_exit); MODULE_LICENSE("GPL"); MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */); MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);
linux-master
net/ipv4/udp_diag.c
// SPDX-License-Identifier: GPL-2.0 /* * xfrm4_state.c * * Changes: * YOSHIFUJI Hideaki @USAGI * Split up af-specific portion * */ #include <net/xfrm.h> static struct xfrm_state_afinfo xfrm4_state_afinfo = { .family = AF_INET, .proto = IPPROTO_IPIP, .output = xfrm4_output, .transport_finish = xfrm4_transport_finish, .local_error = xfrm4_local_error, }; void __init xfrm4_state_init(void) { xfrm_state_register_afinfo(&xfrm4_state_afinfo); }
linux-master
net/ipv4/xfrm4_state.c
// SPDX-License-Identifier: GPL-2.0 /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * The IP forwarding functionality. * * Authors: see ip.c * * Fixes: * Many : Split from ip.c , see ip_input.c for * history. * Dave Gregorich : NULL ip_rt_put fix for multicast * routing. * Jos Vos : Add call_out_firewall before sending, * use output device for accounting. * Jos Vos : Call forward firewall after routing * (always use output device). * Mike McLagan : Routing by source */ #include <linux/types.h> #include <linux/mm.h> #include <linux/skbuff.h> #include <linux/ip.h> #include <linux/icmp.h> #include <linux/netdevice.h> #include <linux/slab.h> #include <net/sock.h> #include <net/ip.h> #include <net/tcp.h> #include <net/udp.h> #include <net/icmp.h> #include <linux/tcp.h> #include <linux/udp.h> #include <linux/netfilter_ipv4.h> #include <net/checksum.h> #include <linux/route.h> #include <net/route.h> #include <net/xfrm.h> static bool ip_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu) { if (skb->len <= mtu) return false; if (unlikely((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0)) return false; /* original fragment exceeds mtu and DF is set */ if (unlikely(IPCB(skb)->frag_max_size > mtu)) return true; if (skb->ignore_df) return false; if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu)) return false; return true; } static int ip_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { struct ip_options *opt = &(IPCB(skb)->opt); __IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS); #ifdef CONFIG_NET_SWITCHDEV if (skb->offload_l3_fwd_mark) { consume_skb(skb); return 0; } #endif if (unlikely(opt->optlen)) ip_forward_options(skb); skb_clear_tstamp(skb); return dst_output(net, sk, skb); } int ip_forward(struct sk_buff *skb) { u32 mtu; struct iphdr *iph; /* Our header */ struct rtable *rt; /* Route we use */ struct ip_options *opt = &(IPCB(skb)->opt); struct net *net; SKB_DR(reason); /* that should never happen */ if (skb->pkt_type != PACKET_HOST) goto drop; if (unlikely(skb->sk)) goto drop; if (skb_warn_if_lro(skb)) goto drop; if (!xfrm4_policy_check(NULL, XFRM_POLICY_FWD, skb)) { SKB_DR_SET(reason, XFRM_POLICY); goto drop; } if (IPCB(skb)->opt.router_alert && ip_call_ra_chain(skb)) return NET_RX_SUCCESS; skb_forward_csum(skb); net = dev_net(skb->dev); /* * According to the RFC, we must first decrease the TTL field. If * that reaches zero, we must reply an ICMP control message telling * that the packet's lifetime expired. */ if (ip_hdr(skb)->ttl <= 1) goto too_many_hops; if (!xfrm4_route_forward(skb)) { SKB_DR_SET(reason, XFRM_POLICY); goto drop; } rt = skb_rtable(skb); if (opt->is_strictroute && rt->rt_uses_gateway) goto sr_failed; IPCB(skb)->flags |= IPSKB_FORWARDED; mtu = ip_dst_mtu_maybe_forward(&rt->dst, true); if (ip_exceeds_mtu(skb, mtu)) { IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); SKB_DR_SET(reason, PKT_TOO_BIG); goto drop; } /* We are about to mangle packet. Copy it! */ if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+rt->dst.header_len)) goto drop; iph = ip_hdr(skb); /* Decrease ttl after skb cow done */ ip_decrease_ttl(iph); /* * We now generate an ICMP HOST REDIRECT giving the route * we calculated. */ if (IPCB(skb)->flags & IPSKB_DOREDIRECT && !opt->srr && !skb_sec_path(skb)) ip_rt_send_redirect(skb); if (READ_ONCE(net->ipv4.sysctl_ip_fwd_update_priority)) skb->priority = rt_tos2priority(iph->tos); return NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD, net, NULL, skb, skb->dev, rt->dst.dev, ip_forward_finish); sr_failed: /* * Strict routing permits no gatewaying */ icmp_send(skb, ICMP_DEST_UNREACH, ICMP_SR_FAILED, 0); goto drop; too_many_hops: /* Tell the sender its packet died... */ __IP_INC_STATS(net, IPSTATS_MIB_INHDRERRORS); icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0); SKB_DR_SET(reason, IP_INHDR); drop: kfree_skb_reason(skb, reason); return NET_RX_DROP; }
linux-master
net/ipv4/ip_forward.c
// SPDX-License-Identifier: GPL-2.0 /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Implementation of the Transmission Control Protocol(TCP). * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * Mark Evans, <[email protected]> * Corey Minyard <[email protected]> * Florian La Roche, <[email protected]> * Charles Hedrick, <[email protected]> * Linus Torvalds, <[email protected]> * Alan Cox, <[email protected]> * Matthew Dillon, <[email protected]> * Arnt Gulbrandsen, <[email protected]> * Jorge Cwik, <[email protected]> */ /* * Changes: * Pedro Roque : Fast Retransmit/Recovery. * Two receive queues. * Retransmit queue handled by TCP. * Better retransmit timer handling. * New congestion avoidance. * Header prediction. * Variable renaming. * * Eric : Fast Retransmit. * Randy Scott : MSS option defines. * Eric Schenk : Fixes to slow start algorithm. * Eric Schenk : Yet another double ACK bug. * Eric Schenk : Delayed ACK bug fixes. * Eric Schenk : Floyd style fast retrans war avoidance. * David S. Miller : Don't allow zero congestion window. * Eric Schenk : Fix retransmitter so that it sends * next packet on ack of previous packet. * Andi Kleen : Moved open_request checking here * and process RSTs for open_requests. * Andi Kleen : Better prune_queue, and other fixes. * Andrey Savochkin: Fix RTT measurements in the presence of * timestamps. * Andrey Savochkin: Check sequence numbers correctly when * removing SACKs due to in sequence incoming * data segments. * Andi Kleen: Make sure we never ack data there is not * enough room for. Also make this condition * a fatal error if it might still happen. * Andi Kleen: Add tcp_measure_rcv_mss to make * connections with MSS<min(MTU,ann. MSS) * work without delayed acks. * Andi Kleen: Process packets with PSH set in the * fast path. * J Hadi Salim: ECN support * Andrei Gurtov, * Pasi Sarolahti, * Panu Kuhlberg: Experimental audit of TCP (re)transmission * engine. Lots of bugs are found. * Pasi Sarolahti: F-RTO for dealing with spurious RTOs */ #define pr_fmt(fmt) "TCP: " fmt #include <linux/mm.h> #include <linux/slab.h> #include <linux/module.h> #include <linux/sysctl.h> #include <linux/kernel.h> #include <linux/prefetch.h> #include <net/dst.h> #include <net/tcp.h> #include <net/inet_common.h> #include <linux/ipsec.h> #include <asm/unaligned.h> #include <linux/errqueue.h> #include <trace/events/tcp.h> #include <linux/jump_label_ratelimit.h> #include <net/busy_poll.h> #include <net/mptcp.h> int sysctl_tcp_max_orphans __read_mostly = NR_FILE; #define FLAG_DATA 0x01 /* Incoming frame contained data. */ #define FLAG_WIN_UPDATE 0x02 /* Incoming ACK was a window update. */ #define FLAG_DATA_ACKED 0x04 /* This ACK acknowledged new data. */ #define FLAG_RETRANS_DATA_ACKED 0x08 /* "" "" some of which was retransmitted. */ #define FLAG_SYN_ACKED 0x10 /* This ACK acknowledged SYN. */ #define FLAG_DATA_SACKED 0x20 /* New SACK. */ #define FLAG_ECE 0x40 /* ECE in this ACK */ #define FLAG_LOST_RETRANS 0x80 /* This ACK marks some retransmission lost */ #define FLAG_SLOWPATH 0x100 /* Do not skip RFC checks for window update.*/ #define FLAG_ORIG_SACK_ACKED 0x200 /* Never retransmitted data are (s)acked */ #define FLAG_SND_UNA_ADVANCED 0x400 /* Snd_una was changed (!= FLAG_DATA_ACKED) */ #define FLAG_DSACKING_ACK 0x800 /* SACK blocks contained D-SACK info */ #define FLAG_SET_XMIT_TIMER 0x1000 /* Set TLP or RTO timer */ #define FLAG_SACK_RENEGING 0x2000 /* snd_una advanced to a sacked seq */ #define FLAG_UPDATE_TS_RECENT 0x4000 /* tcp_replace_ts_recent() */ #define FLAG_NO_CHALLENGE_ACK 0x8000 /* do not call tcp_send_challenge_ack() */ #define FLAG_ACK_MAYBE_DELAYED 0x10000 /* Likely a delayed ACK */ #define FLAG_DSACK_TLP 0x20000 /* DSACK for tail loss probe */ #define FLAG_ACKED (FLAG_DATA_ACKED|FLAG_SYN_ACKED) #define FLAG_NOT_DUP (FLAG_DATA|FLAG_WIN_UPDATE|FLAG_ACKED) #define FLAG_CA_ALERT (FLAG_DATA_SACKED|FLAG_ECE|FLAG_DSACKING_ACK) #define FLAG_FORWARD_PROGRESS (FLAG_ACKED|FLAG_DATA_SACKED) #define TCP_REMNANT (TCP_FLAG_FIN|TCP_FLAG_URG|TCP_FLAG_SYN|TCP_FLAG_PSH) #define TCP_HP_BITS (~(TCP_RESERVED_BITS|TCP_FLAG_PSH)) #define REXMIT_NONE 0 /* no loss recovery to do */ #define REXMIT_LOST 1 /* retransmit packets marked lost */ #define REXMIT_NEW 2 /* FRTO-style transmit of unsent/new packets */ #if IS_ENABLED(CONFIG_TLS_DEVICE) static DEFINE_STATIC_KEY_DEFERRED_FALSE(clean_acked_data_enabled, HZ); void clean_acked_data_enable(struct inet_connection_sock *icsk, void (*cad)(struct sock *sk, u32 ack_seq)) { icsk->icsk_clean_acked = cad; static_branch_deferred_inc(&clean_acked_data_enabled); } EXPORT_SYMBOL_GPL(clean_acked_data_enable); void clean_acked_data_disable(struct inet_connection_sock *icsk) { static_branch_slow_dec_deferred(&clean_acked_data_enabled); icsk->icsk_clean_acked = NULL; } EXPORT_SYMBOL_GPL(clean_acked_data_disable); void clean_acked_data_flush(void) { static_key_deferred_flush(&clean_acked_data_enabled); } EXPORT_SYMBOL_GPL(clean_acked_data_flush); #endif #ifdef CONFIG_CGROUP_BPF static void bpf_skops_parse_hdr(struct sock *sk, struct sk_buff *skb) { bool unknown_opt = tcp_sk(sk)->rx_opt.saw_unknown && BPF_SOCK_OPS_TEST_FLAG(tcp_sk(sk), BPF_SOCK_OPS_PARSE_UNKNOWN_HDR_OPT_CB_FLAG); bool parse_all_opt = BPF_SOCK_OPS_TEST_FLAG(tcp_sk(sk), BPF_SOCK_OPS_PARSE_ALL_HDR_OPT_CB_FLAG); struct bpf_sock_ops_kern sock_ops; if (likely(!unknown_opt && !parse_all_opt)) return; /* The skb will be handled in the * bpf_skops_established() or * bpf_skops_write_hdr_opt(). */ switch (sk->sk_state) { case TCP_SYN_RECV: case TCP_SYN_SENT: case TCP_LISTEN: return; } sock_owned_by_me(sk); memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp)); sock_ops.op = BPF_SOCK_OPS_PARSE_HDR_OPT_CB; sock_ops.is_fullsock = 1; sock_ops.sk = sk; bpf_skops_init_skb(&sock_ops, skb, tcp_hdrlen(skb)); BPF_CGROUP_RUN_PROG_SOCK_OPS(&sock_ops); } static void bpf_skops_established(struct sock *sk, int bpf_op, struct sk_buff *skb) { struct bpf_sock_ops_kern sock_ops; sock_owned_by_me(sk); memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp)); sock_ops.op = bpf_op; sock_ops.is_fullsock = 1; sock_ops.sk = sk; /* sk with TCP_REPAIR_ON does not have skb in tcp_finish_connect */ if (skb) bpf_skops_init_skb(&sock_ops, skb, tcp_hdrlen(skb)); BPF_CGROUP_RUN_PROG_SOCK_OPS(&sock_ops); } #else static void bpf_skops_parse_hdr(struct sock *sk, struct sk_buff *skb) { } static void bpf_skops_established(struct sock *sk, int bpf_op, struct sk_buff *skb) { } #endif static void tcp_gro_dev_warn(struct sock *sk, const struct sk_buff *skb, unsigned int len) { static bool __once __read_mostly; if (!__once) { struct net_device *dev; __once = true; rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(sk), skb->skb_iif); if (!dev || len >= dev->mtu) pr_warn("%s: Driver has suspect GRO implementation, TCP performance may be compromised.\n", dev ? dev->name : "Unknown driver"); rcu_read_unlock(); } } /* Adapt the MSS value used to make delayed ack decision to the * real world. */ static void tcp_measure_rcv_mss(struct sock *sk, const struct sk_buff *skb) { struct inet_connection_sock *icsk = inet_csk(sk); const unsigned int lss = icsk->icsk_ack.last_seg_size; unsigned int len; icsk->icsk_ack.last_seg_size = 0; /* skb->len may jitter because of SACKs, even if peer * sends good full-sized frames. */ len = skb_shinfo(skb)->gso_size ? : skb->len; if (len >= icsk->icsk_ack.rcv_mss) { /* Note: divides are still a bit expensive. * For the moment, only adjust scaling_ratio * when we update icsk_ack.rcv_mss. */ if (unlikely(len != icsk->icsk_ack.rcv_mss)) { u64 val = (u64)skb->len << TCP_RMEM_TO_WIN_SCALE; do_div(val, skb->truesize); tcp_sk(sk)->scaling_ratio = val ? val : 1; } icsk->icsk_ack.rcv_mss = min_t(unsigned int, len, tcp_sk(sk)->advmss); /* Account for possibly-removed options */ if (unlikely(len > icsk->icsk_ack.rcv_mss + MAX_TCP_OPTION_SPACE)) tcp_gro_dev_warn(sk, skb, len); } else { /* Otherwise, we make more careful check taking into account, * that SACKs block is variable. * * "len" is invariant segment length, including TCP header. */ len += skb->data - skb_transport_header(skb); if (len >= TCP_MSS_DEFAULT + sizeof(struct tcphdr) || /* If PSH is not set, packet should be * full sized, provided peer TCP is not badly broken. * This observation (if it is correct 8)) allows * to handle super-low mtu links fairly. */ (len >= TCP_MIN_MSS + sizeof(struct tcphdr) && !(tcp_flag_word(tcp_hdr(skb)) & TCP_REMNANT))) { /* Subtract also invariant (if peer is RFC compliant), * tcp header plus fixed timestamp option length. * Resulting "len" is MSS free of SACK jitter. */ len -= tcp_sk(sk)->tcp_header_len; icsk->icsk_ack.last_seg_size = len; if (len == lss) { icsk->icsk_ack.rcv_mss = len; return; } } if (icsk->icsk_ack.pending & ICSK_ACK_PUSHED) icsk->icsk_ack.pending |= ICSK_ACK_PUSHED2; icsk->icsk_ack.pending |= ICSK_ACK_PUSHED; } } static void tcp_incr_quickack(struct sock *sk, unsigned int max_quickacks) { struct inet_connection_sock *icsk = inet_csk(sk); unsigned int quickacks = tcp_sk(sk)->rcv_wnd / (2 * icsk->icsk_ack.rcv_mss); if (quickacks == 0) quickacks = 2; quickacks = min(quickacks, max_quickacks); if (quickacks > icsk->icsk_ack.quick) icsk->icsk_ack.quick = quickacks; } static void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks) { struct inet_connection_sock *icsk = inet_csk(sk); tcp_incr_quickack(sk, max_quickacks); inet_csk_exit_pingpong_mode(sk); icsk->icsk_ack.ato = TCP_ATO_MIN; } /* Send ACKs quickly, if "quick" count is not exhausted * and the session is not interactive. */ static bool tcp_in_quickack_mode(struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); const struct dst_entry *dst = __sk_dst_get(sk); return (dst && dst_metric(dst, RTAX_QUICKACK)) || (icsk->icsk_ack.quick && !inet_csk_in_pingpong_mode(sk)); } static void tcp_ecn_queue_cwr(struct tcp_sock *tp) { if (tp->ecn_flags & TCP_ECN_OK) tp->ecn_flags |= TCP_ECN_QUEUE_CWR; } static void tcp_ecn_accept_cwr(struct sock *sk, const struct sk_buff *skb) { if (tcp_hdr(skb)->cwr) { tcp_sk(sk)->ecn_flags &= ~TCP_ECN_DEMAND_CWR; /* If the sender is telling us it has entered CWR, then its * cwnd may be very low (even just 1 packet), so we should ACK * immediately. */ if (TCP_SKB_CB(skb)->seq != TCP_SKB_CB(skb)->end_seq) inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW; } } static void tcp_ecn_withdraw_cwr(struct tcp_sock *tp) { tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR; } static void __tcp_ecn_check_ce(struct sock *sk, const struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); switch (TCP_SKB_CB(skb)->ip_dsfield & INET_ECN_MASK) { case INET_ECN_NOT_ECT: /* Funny extension: if ECT is not set on a segment, * and we already seen ECT on a previous segment, * it is probably a retransmit. */ if (tp->ecn_flags & TCP_ECN_SEEN) tcp_enter_quickack_mode(sk, 2); break; case INET_ECN_CE: if (tcp_ca_needs_ecn(sk)) tcp_ca_event(sk, CA_EVENT_ECN_IS_CE); if (!(tp->ecn_flags & TCP_ECN_DEMAND_CWR)) { /* Better not delay acks, sender can have a very low cwnd */ tcp_enter_quickack_mode(sk, 2); tp->ecn_flags |= TCP_ECN_DEMAND_CWR; } tp->ecn_flags |= TCP_ECN_SEEN; break; default: if (tcp_ca_needs_ecn(sk)) tcp_ca_event(sk, CA_EVENT_ECN_NO_CE); tp->ecn_flags |= TCP_ECN_SEEN; break; } } static void tcp_ecn_check_ce(struct sock *sk, const struct sk_buff *skb) { if (tcp_sk(sk)->ecn_flags & TCP_ECN_OK) __tcp_ecn_check_ce(sk, skb); } static void tcp_ecn_rcv_synack(struct tcp_sock *tp, const struct tcphdr *th) { if ((tp->ecn_flags & TCP_ECN_OK) && (!th->ece || th->cwr)) tp->ecn_flags &= ~TCP_ECN_OK; } static void tcp_ecn_rcv_syn(struct tcp_sock *tp, const struct tcphdr *th) { if ((tp->ecn_flags & TCP_ECN_OK) && (!th->ece || !th->cwr)) tp->ecn_flags &= ~TCP_ECN_OK; } static bool tcp_ecn_rcv_ecn_echo(const struct tcp_sock *tp, const struct tcphdr *th) { if (th->ece && !th->syn && (tp->ecn_flags & TCP_ECN_OK)) return true; return false; } /* Buffer size and advertised window tuning. * * 1. Tuning sk->sk_sndbuf, when connection enters established state. */ static void tcp_sndbuf_expand(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); const struct tcp_congestion_ops *ca_ops = inet_csk(sk)->icsk_ca_ops; int sndmem, per_mss; u32 nr_segs; /* Worst case is non GSO/TSO : each frame consumes one skb * and skb->head is kmalloced using power of two area of memory */ per_mss = max_t(u32, tp->rx_opt.mss_clamp, tp->mss_cache) + MAX_TCP_HEADER + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); per_mss = roundup_pow_of_two(per_mss) + SKB_DATA_ALIGN(sizeof(struct sk_buff)); nr_segs = max_t(u32, TCP_INIT_CWND, tcp_snd_cwnd(tp)); nr_segs = max_t(u32, nr_segs, tp->reordering + 1); /* Fast Recovery (RFC 5681 3.2) : * Cubic needs 1.7 factor, rounded to 2 to include * extra cushion (application might react slowly to EPOLLOUT) */ sndmem = ca_ops->sndbuf_expand ? ca_ops->sndbuf_expand(sk) : 2; sndmem *= nr_segs * per_mss; if (sk->sk_sndbuf < sndmem) WRITE_ONCE(sk->sk_sndbuf, min(sndmem, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[2]))); } /* 2. Tuning advertised window (window_clamp, rcv_ssthresh) * * All tcp_full_space() is split to two parts: "network" buffer, allocated * forward and advertised in receiver window (tp->rcv_wnd) and * "application buffer", required to isolate scheduling/application * latencies from network. * window_clamp is maximal advertised window. It can be less than * tcp_full_space(), in this case tcp_full_space() - window_clamp * is reserved for "application" buffer. The less window_clamp is * the smoother our behaviour from viewpoint of network, but the lower * throughput and the higher sensitivity of the connection to losses. 8) * * rcv_ssthresh is more strict window_clamp used at "slow start" * phase to predict further behaviour of this connection. * It is used for two goals: * - to enforce header prediction at sender, even when application * requires some significant "application buffer". It is check #1. * - to prevent pruning of receive queue because of misprediction * of receiver window. Check #2. * * The scheme does not work when sender sends good segments opening * window and then starts to feed us spaghetti. But it should work * in common situations. Otherwise, we have to rely on queue collapsing. */ /* Slow part of check#2. */ static int __tcp_grow_window(const struct sock *sk, const struct sk_buff *skb, unsigned int skbtruesize) { const struct tcp_sock *tp = tcp_sk(sk); /* Optimize this! */ int truesize = tcp_win_from_space(sk, skbtruesize) >> 1; int window = tcp_win_from_space(sk, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])) >> 1; while (tp->rcv_ssthresh <= window) { if (truesize <= skb->len) return 2 * inet_csk(sk)->icsk_ack.rcv_mss; truesize >>= 1; window >>= 1; } return 0; } /* Even if skb appears to have a bad len/truesize ratio, TCP coalescing * can play nice with us, as sk_buff and skb->head might be either * freed or shared with up to MAX_SKB_FRAGS segments. * Only give a boost to drivers using page frag(s) to hold the frame(s), * and if no payload was pulled in skb->head before reaching us. */ static u32 truesize_adjust(bool adjust, const struct sk_buff *skb) { u32 truesize = skb->truesize; if (adjust && !skb_headlen(skb)) { truesize -= SKB_TRUESIZE(skb_end_offset(skb)); /* paranoid check, some drivers might be buggy */ if (unlikely((int)truesize < (int)skb->len)) truesize = skb->truesize; } return truesize; } static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb, bool adjust) { struct tcp_sock *tp = tcp_sk(sk); int room; room = min_t(int, tp->window_clamp, tcp_space(sk)) - tp->rcv_ssthresh; if (room <= 0) return; /* Check #1 */ if (!tcp_under_memory_pressure(sk)) { unsigned int truesize = truesize_adjust(adjust, skb); int incr; /* Check #2. Increase window, if skb with such overhead * will fit to rcvbuf in future. */ if (tcp_win_from_space(sk, truesize) <= skb->len) incr = 2 * tp->advmss; else incr = __tcp_grow_window(sk, skb, truesize); if (incr) { incr = max_t(int, incr, 2 * skb->len); tp->rcv_ssthresh += min(room, incr); inet_csk(sk)->icsk_ack.quick |= 1; } } else { /* Under pressure: * Adjust rcv_ssthresh according to reserved mem */ tcp_adjust_rcv_ssthresh(sk); } } /* 3. Try to fixup all. It is made immediately after connection enters * established state. */ static void tcp_init_buffer_space(struct sock *sk) { int tcp_app_win = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_app_win); struct tcp_sock *tp = tcp_sk(sk); int maxwin; if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) tcp_sndbuf_expand(sk); tcp_mstamp_refresh(tp); tp->rcvq_space.time = tp->tcp_mstamp; tp->rcvq_space.seq = tp->copied_seq; maxwin = tcp_full_space(sk); if (tp->window_clamp >= maxwin) { tp->window_clamp = maxwin; if (tcp_app_win && maxwin > 4 * tp->advmss) tp->window_clamp = max(maxwin - (maxwin >> tcp_app_win), 4 * tp->advmss); } /* Force reservation of one segment. */ if (tcp_app_win && tp->window_clamp > 2 * tp->advmss && tp->window_clamp + tp->advmss > maxwin) tp->window_clamp = max(2 * tp->advmss, maxwin - tp->advmss); tp->rcv_ssthresh = min(tp->rcv_ssthresh, tp->window_clamp); tp->snd_cwnd_stamp = tcp_jiffies32; tp->rcvq_space.space = min3(tp->rcv_ssthresh, tp->rcv_wnd, (u32)TCP_INIT_CWND * tp->advmss); } /* 4. Recalculate window clamp after socket hit its memory bounds. */ static void tcp_clamp_window(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); struct net *net = sock_net(sk); int rmem2; icsk->icsk_ack.quick = 0; rmem2 = READ_ONCE(net->ipv4.sysctl_tcp_rmem[2]); if (sk->sk_rcvbuf < rmem2 && !(sk->sk_userlocks & SOCK_RCVBUF_LOCK) && !tcp_under_memory_pressure(sk) && sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)) { WRITE_ONCE(sk->sk_rcvbuf, min(atomic_read(&sk->sk_rmem_alloc), rmem2)); } if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) tp->rcv_ssthresh = min(tp->window_clamp, 2U * tp->advmss); } /* Initialize RCV_MSS value. * RCV_MSS is an our guess about MSS used by the peer. * We haven't any direct information about the MSS. * It's better to underestimate the RCV_MSS rather than overestimate. * Overestimations make us ACKing less frequently than needed. * Underestimations are more easy to detect and fix by tcp_measure_rcv_mss(). */ void tcp_initialize_rcv_mss(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); unsigned int hint = min_t(unsigned int, tp->advmss, tp->mss_cache); hint = min(hint, tp->rcv_wnd / 2); hint = min(hint, TCP_MSS_DEFAULT); hint = max(hint, TCP_MIN_MSS); inet_csk(sk)->icsk_ack.rcv_mss = hint; } EXPORT_SYMBOL(tcp_initialize_rcv_mss); /* Receiver "autotuning" code. * * The algorithm for RTT estimation w/o timestamps is based on * Dynamic Right-Sizing (DRS) by Wu Feng and Mike Fisk of LANL. * <https://public.lanl.gov/radiant/pubs.html#DRS> * * More detail on this code can be found at * <http://staff.psc.edu/jheffner/>, * though this reference is out of date. A new paper * is pending. */ static void tcp_rcv_rtt_update(struct tcp_sock *tp, u32 sample, int win_dep) { u32 new_sample = tp->rcv_rtt_est.rtt_us; long m = sample; if (new_sample != 0) { /* If we sample in larger samples in the non-timestamp * case, we could grossly overestimate the RTT especially * with chatty applications or bulk transfer apps which * are stalled on filesystem I/O. * * Also, since we are only going for a minimum in the * non-timestamp case, we do not smooth things out * else with timestamps disabled convergence takes too * long. */ if (!win_dep) { m -= (new_sample >> 3); new_sample += m; } else { m <<= 3; if (m < new_sample) new_sample = m; } } else { /* No previous measure. */ new_sample = m << 3; } tp->rcv_rtt_est.rtt_us = new_sample; } static inline void tcp_rcv_rtt_measure(struct tcp_sock *tp) { u32 delta_us; if (tp->rcv_rtt_est.time == 0) goto new_measure; if (before(tp->rcv_nxt, tp->rcv_rtt_est.seq)) return; delta_us = tcp_stamp_us_delta(tp->tcp_mstamp, tp->rcv_rtt_est.time); if (!delta_us) delta_us = 1; tcp_rcv_rtt_update(tp, delta_us, 1); new_measure: tp->rcv_rtt_est.seq = tp->rcv_nxt + tp->rcv_wnd; tp->rcv_rtt_est.time = tp->tcp_mstamp; } static inline void tcp_rcv_rtt_measure_ts(struct sock *sk, const struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); if (tp->rx_opt.rcv_tsecr == tp->rcv_rtt_last_tsecr) return; tp->rcv_rtt_last_tsecr = tp->rx_opt.rcv_tsecr; if (TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq >= inet_csk(sk)->icsk_ack.rcv_mss) { u32 delta = tcp_time_stamp(tp) - tp->rx_opt.rcv_tsecr; u32 delta_us; if (likely(delta < INT_MAX / (USEC_PER_SEC / TCP_TS_HZ))) { if (!delta) delta = 1; delta_us = delta * (USEC_PER_SEC / TCP_TS_HZ); tcp_rcv_rtt_update(tp, delta_us, 0); } } } /* * This function should be called every time data is copied to user space. * It calculates the appropriate TCP receive buffer space. */ void tcp_rcv_space_adjust(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); u32 copied; int time; trace_tcp_rcv_space_adjust(sk); tcp_mstamp_refresh(tp); time = tcp_stamp_us_delta(tp->tcp_mstamp, tp->rcvq_space.time); if (time < (tp->rcv_rtt_est.rtt_us >> 3) || tp->rcv_rtt_est.rtt_us == 0) return; /* Number of bytes copied to user in last RTT */ copied = tp->copied_seq - tp->rcvq_space.seq; if (copied <= tp->rcvq_space.space) goto new_measure; /* A bit of theory : * copied = bytes received in previous RTT, our base window * To cope with packet losses, we need a 2x factor * To cope with slow start, and sender growing its cwin by 100 % * every RTT, we need a 4x factor, because the ACK we are sending * now is for the next RTT, not the current one : * <prev RTT . ><current RTT .. ><next RTT .... > */ if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_moderate_rcvbuf) && !(sk->sk_userlocks & SOCK_RCVBUF_LOCK)) { u64 rcvwin, grow; int rcvbuf; /* minimal window to cope with packet losses, assuming * steady state. Add some cushion because of small variations. */ rcvwin = ((u64)copied << 1) + 16 * tp->advmss; /* Accommodate for sender rate increase (eg. slow start) */ grow = rcvwin * (copied - tp->rcvq_space.space); do_div(grow, tp->rcvq_space.space); rcvwin += (grow << 1); rcvbuf = min_t(u64, tcp_space_from_win(sk, rcvwin), READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])); if (rcvbuf > sk->sk_rcvbuf) { WRITE_ONCE(sk->sk_rcvbuf, rcvbuf); /* Make the window clamp follow along. */ tp->window_clamp = tcp_win_from_space(sk, rcvbuf); } } tp->rcvq_space.space = copied; new_measure: tp->rcvq_space.seq = tp->copied_seq; tp->rcvq_space.time = tp->tcp_mstamp; } /* There is something which you must keep in mind when you analyze the * behavior of the tp->ato delayed ack timeout interval. When a * connection starts up, we want to ack as quickly as possible. The * problem is that "good" TCP's do slow start at the beginning of data * transmission. The means that until we send the first few ACK's the * sender will sit on his end and only queue most of his data, because * he can only send snd_cwnd unacked packets at any given time. For * each ACK we send, he increments snd_cwnd and transmits more of his * queue. -DaveM */ static void tcp_event_data_recv(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); u32 now; inet_csk_schedule_ack(sk); tcp_measure_rcv_mss(sk, skb); tcp_rcv_rtt_measure(tp); now = tcp_jiffies32; if (!icsk->icsk_ack.ato) { /* The _first_ data packet received, initialize * delayed ACK engine. */ tcp_incr_quickack(sk, TCP_MAX_QUICKACKS); icsk->icsk_ack.ato = TCP_ATO_MIN; } else { int m = now - icsk->icsk_ack.lrcvtime; if (m <= TCP_ATO_MIN / 2) { /* The fastest case is the first. */ icsk->icsk_ack.ato = (icsk->icsk_ack.ato >> 1) + TCP_ATO_MIN / 2; } else if (m < icsk->icsk_ack.ato) { icsk->icsk_ack.ato = (icsk->icsk_ack.ato >> 1) + m; if (icsk->icsk_ack.ato > icsk->icsk_rto) icsk->icsk_ack.ato = icsk->icsk_rto; } else if (m > icsk->icsk_rto) { /* Too long gap. Apparently sender failed to * restart window, so that we send ACKs quickly. */ tcp_incr_quickack(sk, TCP_MAX_QUICKACKS); } } icsk->icsk_ack.lrcvtime = now; tcp_ecn_check_ce(sk, skb); if (skb->len >= 128) tcp_grow_window(sk, skb, true); } /* Called to compute a smoothed rtt estimate. The data fed to this * routine either comes from timestamps, or from segments that were * known _not_ to have been retransmitted [see Karn/Partridge * Proceedings SIGCOMM 87]. The algorithm is from the SIGCOMM 88 * piece by Van Jacobson. * NOTE: the next three routines used to be one big routine. * To save cycles in the RFC 1323 implementation it was better to break * it up into three procedures. -- erics */ static void tcp_rtt_estimator(struct sock *sk, long mrtt_us) { struct tcp_sock *tp = tcp_sk(sk); long m = mrtt_us; /* RTT */ u32 srtt = tp->srtt_us; /* The following amusing code comes from Jacobson's * article in SIGCOMM '88. Note that rtt and mdev * are scaled versions of rtt and mean deviation. * This is designed to be as fast as possible * m stands for "measurement". * * On a 1990 paper the rto value is changed to: * RTO = rtt + 4 * mdev * * Funny. This algorithm seems to be very broken. * These formulae increase RTO, when it should be decreased, increase * too slowly, when it should be increased quickly, decrease too quickly * etc. I guess in BSD RTO takes ONE value, so that it is absolutely * does not matter how to _calculate_ it. Seems, it was trap * that VJ failed to avoid. 8) */ if (srtt != 0) { m -= (srtt >> 3); /* m is now error in rtt est */ srtt += m; /* rtt = 7/8 rtt + 1/8 new */ if (m < 0) { m = -m; /* m is now abs(error) */ m -= (tp->mdev_us >> 2); /* similar update on mdev */ /* This is similar to one of Eifel findings. * Eifel blocks mdev updates when rtt decreases. * This solution is a bit different: we use finer gain * for mdev in this case (alpha*beta). * Like Eifel it also prevents growth of rto, * but also it limits too fast rto decreases, * happening in pure Eifel. */ if (m > 0) m >>= 3; } else { m -= (tp->mdev_us >> 2); /* similar update on mdev */ } tp->mdev_us += m; /* mdev = 3/4 mdev + 1/4 new */ if (tp->mdev_us > tp->mdev_max_us) { tp->mdev_max_us = tp->mdev_us; if (tp->mdev_max_us > tp->rttvar_us) tp->rttvar_us = tp->mdev_max_us; } if (after(tp->snd_una, tp->rtt_seq)) { if (tp->mdev_max_us < tp->rttvar_us) tp->rttvar_us -= (tp->rttvar_us - tp->mdev_max_us) >> 2; tp->rtt_seq = tp->snd_nxt; tp->mdev_max_us = tcp_rto_min_us(sk); tcp_bpf_rtt(sk); } } else { /* no previous measure. */ srtt = m << 3; /* take the measured time to be rtt */ tp->mdev_us = m << 1; /* make sure rto = 3*rtt */ tp->rttvar_us = max(tp->mdev_us, tcp_rto_min_us(sk)); tp->mdev_max_us = tp->rttvar_us; tp->rtt_seq = tp->snd_nxt; tcp_bpf_rtt(sk); } tp->srtt_us = max(1U, srtt); } static void tcp_update_pacing_rate(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); u64 rate; /* set sk_pacing_rate to 200 % of current rate (mss * cwnd / srtt) */ rate = (u64)tp->mss_cache * ((USEC_PER_SEC / 100) << 3); /* current rate is (cwnd * mss) / srtt * In Slow Start [1], set sk_pacing_rate to 200 % the current rate. * In Congestion Avoidance phase, set it to 120 % the current rate. * * [1] : Normal Slow Start condition is (tp->snd_cwnd < tp->snd_ssthresh) * If snd_cwnd >= (tp->snd_ssthresh / 2), we are approaching * end of slow start and should slow down. */ if (tcp_snd_cwnd(tp) < tp->snd_ssthresh / 2) rate *= READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_pacing_ss_ratio); else rate *= READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_pacing_ca_ratio); rate *= max(tcp_snd_cwnd(tp), tp->packets_out); if (likely(tp->srtt_us)) do_div(rate, tp->srtt_us); /* WRITE_ONCE() is needed because sch_fq fetches sk_pacing_rate * without any lock. We want to make sure compiler wont store * intermediate values in this location. */ WRITE_ONCE(sk->sk_pacing_rate, min_t(u64, rate, sk->sk_max_pacing_rate)); } /* Calculate rto without backoff. This is the second half of Van Jacobson's * routine referred to above. */ static void tcp_set_rto(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); /* Old crap is replaced with new one. 8) * * More seriously: * 1. If rtt variance happened to be less 50msec, it is hallucination. * It cannot be less due to utterly erratic ACK generation made * at least by solaris and freebsd. "Erratic ACKs" has _nothing_ * to do with delayed acks, because at cwnd>2 true delack timeout * is invisible. Actually, Linux-2.4 also generates erratic * ACKs in some circumstances. */ inet_csk(sk)->icsk_rto = __tcp_set_rto(tp); /* 2. Fixups made earlier cannot be right. * If we do not estimate RTO correctly without them, * all the algo is pure shit and should be replaced * with correct one. It is exactly, which we pretend to do. */ /* NOTE: clamping at TCP_RTO_MIN is not required, current algo * guarantees that rto is higher. */ tcp_bound_rto(sk); } __u32 tcp_init_cwnd(const struct tcp_sock *tp, const struct dst_entry *dst) { __u32 cwnd = (dst ? dst_metric(dst, RTAX_INITCWND) : 0); if (!cwnd) cwnd = TCP_INIT_CWND; return min_t(__u32, cwnd, tp->snd_cwnd_clamp); } struct tcp_sacktag_state { /* Timestamps for earliest and latest never-retransmitted segment * that was SACKed. RTO needs the earliest RTT to stay conservative, * but congestion control should still get an accurate delay signal. */ u64 first_sackt; u64 last_sackt; u32 reord; u32 sack_delivered; int flag; unsigned int mss_now; struct rate_sample *rate; }; /* Take a notice that peer is sending D-SACKs. Skip update of data delivery * and spurious retransmission information if this DSACK is unlikely caused by * sender's action: * - DSACKed sequence range is larger than maximum receiver's window. * - Total no. of DSACKed segments exceed the total no. of retransmitted segs. */ static u32 tcp_dsack_seen(struct tcp_sock *tp, u32 start_seq, u32 end_seq, struct tcp_sacktag_state *state) { u32 seq_len, dup_segs = 1; if (!before(start_seq, end_seq)) return 0; seq_len = end_seq - start_seq; /* Dubious DSACK: DSACKed range greater than maximum advertised rwnd */ if (seq_len > tp->max_window) return 0; if (seq_len > tp->mss_cache) dup_segs = DIV_ROUND_UP(seq_len, tp->mss_cache); else if (tp->tlp_high_seq && tp->tlp_high_seq == end_seq) state->flag |= FLAG_DSACK_TLP; tp->dsack_dups += dup_segs; /* Skip the DSACK if dup segs weren't retransmitted by sender */ if (tp->dsack_dups > tp->total_retrans) return 0; tp->rx_opt.sack_ok |= TCP_DSACK_SEEN; /* We increase the RACK ordering window in rounds where we receive * DSACKs that may have been due to reordering causing RACK to trigger * a spurious fast recovery. Thus RACK ignores DSACKs that happen * without having seen reordering, or that match TLP probes (TLP * is timer-driven, not triggered by RACK). */ if (tp->reord_seen && !(state->flag & FLAG_DSACK_TLP)) tp->rack.dsack_seen = 1; state->flag |= FLAG_DSACKING_ACK; /* A spurious retransmission is delivered */ state->sack_delivered += dup_segs; return dup_segs; } /* It's reordering when higher sequence was delivered (i.e. sacked) before * some lower never-retransmitted sequence ("low_seq"). The maximum reordering * distance is approximated in full-mss packet distance ("reordering"). */ static void tcp_check_sack_reordering(struct sock *sk, const u32 low_seq, const int ts) { struct tcp_sock *tp = tcp_sk(sk); const u32 mss = tp->mss_cache; u32 fack, metric; fack = tcp_highest_sack_seq(tp); if (!before(low_seq, fack)) return; metric = fack - low_seq; if ((metric > tp->reordering * mss) && mss) { #if FASTRETRANS_DEBUG > 1 pr_debug("Disorder%d %d %u f%u s%u rr%d\n", tp->rx_opt.sack_ok, inet_csk(sk)->icsk_ca_state, tp->reordering, 0, tp->sacked_out, tp->undo_marker ? tp->undo_retrans : 0); #endif tp->reordering = min_t(u32, (metric + mss - 1) / mss, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_max_reordering)); } /* This exciting event is worth to be remembered. 8) */ tp->reord_seen++; NET_INC_STATS(sock_net(sk), ts ? LINUX_MIB_TCPTSREORDER : LINUX_MIB_TCPSACKREORDER); } /* This must be called before lost_out or retrans_out are updated * on a new loss, because we want to know if all skbs previously * known to be lost have already been retransmitted, indicating * that this newly lost skb is our next skb to retransmit. */ static void tcp_verify_retransmit_hint(struct tcp_sock *tp, struct sk_buff *skb) { if ((!tp->retransmit_skb_hint && tp->retrans_out >= tp->lost_out) || (tp->retransmit_skb_hint && before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(tp->retransmit_skb_hint)->seq))) tp->retransmit_skb_hint = skb; } /* Sum the number of packets on the wire we have marked as lost, and * notify the congestion control module that the given skb was marked lost. */ static void tcp_notify_skb_loss_event(struct tcp_sock *tp, const struct sk_buff *skb) { tp->lost += tcp_skb_pcount(skb); } void tcp_mark_skb_lost(struct sock *sk, struct sk_buff *skb) { __u8 sacked = TCP_SKB_CB(skb)->sacked; struct tcp_sock *tp = tcp_sk(sk); if (sacked & TCPCB_SACKED_ACKED) return; tcp_verify_retransmit_hint(tp, skb); if (sacked & TCPCB_LOST) { if (sacked & TCPCB_SACKED_RETRANS) { /* Account for retransmits that are lost again */ TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS; tp->retrans_out -= tcp_skb_pcount(skb); NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPLOSTRETRANSMIT, tcp_skb_pcount(skb)); tcp_notify_skb_loss_event(tp, skb); } } else { tp->lost_out += tcp_skb_pcount(skb); TCP_SKB_CB(skb)->sacked |= TCPCB_LOST; tcp_notify_skb_loss_event(tp, skb); } } /* Updates the delivered and delivered_ce counts */ static void tcp_count_delivered(struct tcp_sock *tp, u32 delivered, bool ece_ack) { tp->delivered += delivered; if (ece_ack) tp->delivered_ce += delivered; } /* This procedure tags the retransmission queue when SACKs arrive. * * We have three tag bits: SACKED(S), RETRANS(R) and LOST(L). * Packets in queue with these bits set are counted in variables * sacked_out, retrans_out and lost_out, correspondingly. * * Valid combinations are: * Tag InFlight Description * 0 1 - orig segment is in flight. * S 0 - nothing flies, orig reached receiver. * L 0 - nothing flies, orig lost by net. * R 2 - both orig and retransmit are in flight. * L|R 1 - orig is lost, retransmit is in flight. * S|R 1 - orig reached receiver, retrans is still in flight. * (L|S|R is logically valid, it could occur when L|R is sacked, * but it is equivalent to plain S and code short-curcuits it to S. * L|S is logically invalid, it would mean -1 packet in flight 8)) * * These 6 states form finite state machine, controlled by the following events: * 1. New ACK (+SACK) arrives. (tcp_sacktag_write_queue()) * 2. Retransmission. (tcp_retransmit_skb(), tcp_xmit_retransmit_queue()) * 3. Loss detection event of two flavors: * A. Scoreboard estimator decided the packet is lost. * A'. Reno "three dupacks" marks head of queue lost. * B. SACK arrives sacking SND.NXT at the moment, when the * segment was retransmitted. * 4. D-SACK added new rule: D-SACK changes any tag to S. * * It is pleasant to note, that state diagram turns out to be commutative, * so that we are allowed not to be bothered by order of our actions, * when multiple events arrive simultaneously. (see the function below). * * Reordering detection. * -------------------- * Reordering metric is maximal distance, which a packet can be displaced * in packet stream. With SACKs we can estimate it: * * 1. SACK fills old hole and the corresponding segment was not * ever retransmitted -> reordering. Alas, we cannot use it * when segment was retransmitted. * 2. The last flaw is solved with D-SACK. D-SACK arrives * for retransmitted and already SACKed segment -> reordering.. * Both of these heuristics are not used in Loss state, when we cannot * account for retransmits accurately. * * SACK block validation. * ---------------------- * * SACK block range validation checks that the received SACK block fits to * the expected sequence limits, i.e., it is between SND.UNA and SND.NXT. * Note that SND.UNA is not included to the range though being valid because * it means that the receiver is rather inconsistent with itself reporting * SACK reneging when it should advance SND.UNA. Such SACK block this is * perfectly valid, however, in light of RFC2018 which explicitly states * that "SACK block MUST reflect the newest segment. Even if the newest * segment is going to be discarded ...", not that it looks very clever * in case of head skb. Due to potentional receiver driven attacks, we * choose to avoid immediate execution of a walk in write queue due to * reneging and defer head skb's loss recovery to standard loss recovery * procedure that will eventually trigger (nothing forbids us doing this). * * Implements also blockage to start_seq wrap-around. Problem lies in the * fact that though start_seq (s) is before end_seq (i.e., not reversed), * there's no guarantee that it will be before snd_nxt (n). The problem * happens when start_seq resides between end_seq wrap (e_w) and snd_nxt * wrap (s_w): * * <- outs wnd -> <- wrapzone -> * u e n u_w e_w s n_w * | | | | | | | * |<------------+------+----- TCP seqno space --------------+---------->| * ...-- <2^31 ->| |<--------... * ...---- >2^31 ------>| |<--------... * * Current code wouldn't be vulnerable but it's better still to discard such * crazy SACK blocks. Doing this check for start_seq alone closes somewhat * similar case (end_seq after snd_nxt wrap) as earlier reversed check in * snd_nxt wrap -> snd_una region will then become "well defined", i.e., * equal to the ideal case (infinite seqno space without wrap caused issues). * * With D-SACK the lower bound is extended to cover sequence space below * SND.UNA down to undo_marker, which is the last point of interest. Yet * again, D-SACK block must not to go across snd_una (for the same reason as * for the normal SACK blocks, explained above). But there all simplicity * ends, TCP might receive valid D-SACKs below that. As long as they reside * fully below undo_marker they do not affect behavior in anyway and can * therefore be safely ignored. In rare cases (which are more or less * theoretical ones), the D-SACK will nicely cross that boundary due to skb * fragmentation and packet reordering past skb's retransmission. To consider * them correctly, the acceptable range must be extended even more though * the exact amount is rather hard to quantify. However, tp->max_window can * be used as an exaggerated estimate. */ static bool tcp_is_sackblock_valid(struct tcp_sock *tp, bool is_dsack, u32 start_seq, u32 end_seq) { /* Too far in future, or reversed (interpretation is ambiguous) */ if (after(end_seq, tp->snd_nxt) || !before(start_seq, end_seq)) return false; /* Nasty start_seq wrap-around check (see comments above) */ if (!before(start_seq, tp->snd_nxt)) return false; /* In outstanding window? ...This is valid exit for D-SACKs too. * start_seq == snd_una is non-sensical (see comments above) */ if (after(start_seq, tp->snd_una)) return true; if (!is_dsack || !tp->undo_marker) return false; /* ...Then it's D-SACK, and must reside below snd_una completely */ if (after(end_seq, tp->snd_una)) return false; if (!before(start_seq, tp->undo_marker)) return true; /* Too old */ if (!after(end_seq, tp->undo_marker)) return false; /* Undo_marker boundary crossing (overestimates a lot). Known already: * start_seq < undo_marker and end_seq >= undo_marker. */ return !before(start_seq, end_seq - tp->max_window); } static bool tcp_check_dsack(struct sock *sk, const struct sk_buff *ack_skb, struct tcp_sack_block_wire *sp, int num_sacks, u32 prior_snd_una, struct tcp_sacktag_state *state) { struct tcp_sock *tp = tcp_sk(sk); u32 start_seq_0 = get_unaligned_be32(&sp[0].start_seq); u32 end_seq_0 = get_unaligned_be32(&sp[0].end_seq); u32 dup_segs; if (before(start_seq_0, TCP_SKB_CB(ack_skb)->ack_seq)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKRECV); } else if (num_sacks > 1) { u32 end_seq_1 = get_unaligned_be32(&sp[1].end_seq); u32 start_seq_1 = get_unaligned_be32(&sp[1].start_seq); if (after(end_seq_0, end_seq_1) || before(start_seq_0, start_seq_1)) return false; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKOFORECV); } else { return false; } dup_segs = tcp_dsack_seen(tp, start_seq_0, end_seq_0, state); if (!dup_segs) { /* Skip dubious DSACK */ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKIGNOREDDUBIOUS); return false; } NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPDSACKRECVSEGS, dup_segs); /* D-SACK for already forgotten data... Do dumb counting. */ if (tp->undo_marker && tp->undo_retrans > 0 && !after(end_seq_0, prior_snd_una) && after(end_seq_0, tp->undo_marker)) tp->undo_retrans = max_t(int, 0, tp->undo_retrans - dup_segs); return true; } /* Check if skb is fully within the SACK block. In presence of GSO skbs, * the incoming SACK may not exactly match but we can find smaller MSS * aligned portion of it that matches. Therefore we might need to fragment * which may fail and creates some hassle (caller must handle error case * returns). * * FIXME: this could be merged to shift decision code */ static int tcp_match_skb_to_sack(struct sock *sk, struct sk_buff *skb, u32 start_seq, u32 end_seq) { int err; bool in_sack; unsigned int pkt_len; unsigned int mss; in_sack = !after(start_seq, TCP_SKB_CB(skb)->seq) && !before(end_seq, TCP_SKB_CB(skb)->end_seq); if (tcp_skb_pcount(skb) > 1 && !in_sack && after(TCP_SKB_CB(skb)->end_seq, start_seq)) { mss = tcp_skb_mss(skb); in_sack = !after(start_seq, TCP_SKB_CB(skb)->seq); if (!in_sack) { pkt_len = start_seq - TCP_SKB_CB(skb)->seq; if (pkt_len < mss) pkt_len = mss; } else { pkt_len = end_seq - TCP_SKB_CB(skb)->seq; if (pkt_len < mss) return -EINVAL; } /* Round if necessary so that SACKs cover only full MSSes * and/or the remaining small portion (if present) */ if (pkt_len > mss) { unsigned int new_len = (pkt_len / mss) * mss; if (!in_sack && new_len < pkt_len) new_len += mss; pkt_len = new_len; } if (pkt_len >= skb->len && !in_sack) return 0; err = tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb, pkt_len, mss, GFP_ATOMIC); if (err < 0) return err; } return in_sack; } /* Mark the given newly-SACKed range as such, adjusting counters and hints. */ static u8 tcp_sacktag_one(struct sock *sk, struct tcp_sacktag_state *state, u8 sacked, u32 start_seq, u32 end_seq, int dup_sack, int pcount, u64 xmit_time) { struct tcp_sock *tp = tcp_sk(sk); /* Account D-SACK for retransmitted packet. */ if (dup_sack && (sacked & TCPCB_RETRANS)) { if (tp->undo_marker && tp->undo_retrans > 0 && after(end_seq, tp->undo_marker)) tp->undo_retrans = max_t(int, 0, tp->undo_retrans - pcount); if ((sacked & TCPCB_SACKED_ACKED) && before(start_seq, state->reord)) state->reord = start_seq; } /* Nothing to do; acked frame is about to be dropped (was ACKed). */ if (!after(end_seq, tp->snd_una)) return sacked; if (!(sacked & TCPCB_SACKED_ACKED)) { tcp_rack_advance(tp, sacked, end_seq, xmit_time); if (sacked & TCPCB_SACKED_RETRANS) { /* If the segment is not tagged as lost, * we do not clear RETRANS, believing * that retransmission is still in flight. */ if (sacked & TCPCB_LOST) { sacked &= ~(TCPCB_LOST|TCPCB_SACKED_RETRANS); tp->lost_out -= pcount; tp->retrans_out -= pcount; } } else { if (!(sacked & TCPCB_RETRANS)) { /* New sack for not retransmitted frame, * which was in hole. It is reordering. */ if (before(start_seq, tcp_highest_sack_seq(tp)) && before(start_seq, state->reord)) state->reord = start_seq; if (!after(end_seq, tp->high_seq)) state->flag |= FLAG_ORIG_SACK_ACKED; if (state->first_sackt == 0) state->first_sackt = xmit_time; state->last_sackt = xmit_time; } if (sacked & TCPCB_LOST) { sacked &= ~TCPCB_LOST; tp->lost_out -= pcount; } } sacked |= TCPCB_SACKED_ACKED; state->flag |= FLAG_DATA_SACKED; tp->sacked_out += pcount; /* Out-of-order packets delivered */ state->sack_delivered += pcount; /* Lost marker hint past SACKed? Tweak RFC3517 cnt */ if (tp->lost_skb_hint && before(start_seq, TCP_SKB_CB(tp->lost_skb_hint)->seq)) tp->lost_cnt_hint += pcount; } /* D-SACK. We can detect redundant retransmission in S|R and plain R * frames and clear it. undo_retrans is decreased above, L|R frames * are accounted above as well. */ if (dup_sack && (sacked & TCPCB_SACKED_RETRANS)) { sacked &= ~TCPCB_SACKED_RETRANS; tp->retrans_out -= pcount; } return sacked; } /* Shift newly-SACKed bytes from this skb to the immediately previous * already-SACKed sk_buff. Mark the newly-SACKed bytes as such. */ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *prev, struct sk_buff *skb, struct tcp_sacktag_state *state, unsigned int pcount, int shifted, int mss, bool dup_sack) { struct tcp_sock *tp = tcp_sk(sk); u32 start_seq = TCP_SKB_CB(skb)->seq; /* start of newly-SACKed */ u32 end_seq = start_seq + shifted; /* end of newly-SACKed */ BUG_ON(!pcount); /* Adjust counters and hints for the newly sacked sequence * range but discard the return value since prev is already * marked. We must tag the range first because the seq * advancement below implicitly advances * tcp_highest_sack_seq() when skb is highest_sack. */ tcp_sacktag_one(sk, state, TCP_SKB_CB(skb)->sacked, start_seq, end_seq, dup_sack, pcount, tcp_skb_timestamp_us(skb)); tcp_rate_skb_delivered(sk, skb, state->rate); if (skb == tp->lost_skb_hint) tp->lost_cnt_hint += pcount; TCP_SKB_CB(prev)->end_seq += shifted; TCP_SKB_CB(skb)->seq += shifted; tcp_skb_pcount_add(prev, pcount); WARN_ON_ONCE(tcp_skb_pcount(skb) < pcount); tcp_skb_pcount_add(skb, -pcount); /* When we're adding to gso_segs == 1, gso_size will be zero, * in theory this shouldn't be necessary but as long as DSACK * code can come after this skb later on it's better to keep * setting gso_size to something. */ if (!TCP_SKB_CB(prev)->tcp_gso_size) TCP_SKB_CB(prev)->tcp_gso_size = mss; /* CHECKME: To clear or not to clear? Mimics normal skb currently */ if (tcp_skb_pcount(skb) <= 1) TCP_SKB_CB(skb)->tcp_gso_size = 0; /* Difference in this won't matter, both ACKed by the same cumul. ACK */ TCP_SKB_CB(prev)->sacked |= (TCP_SKB_CB(skb)->sacked & TCPCB_EVER_RETRANS); if (skb->len > 0) { BUG_ON(!tcp_skb_pcount(skb)); NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKSHIFTED); return false; } /* Whole SKB was eaten :-) */ if (skb == tp->retransmit_skb_hint) tp->retransmit_skb_hint = prev; if (skb == tp->lost_skb_hint) { tp->lost_skb_hint = prev; tp->lost_cnt_hint -= tcp_skb_pcount(prev); } TCP_SKB_CB(prev)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags; TCP_SKB_CB(prev)->eor = TCP_SKB_CB(skb)->eor; if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) TCP_SKB_CB(prev)->end_seq++; if (skb == tcp_highest_sack(sk)) tcp_advance_highest_sack(sk, skb); tcp_skb_collapse_tstamp(prev, skb); if (unlikely(TCP_SKB_CB(prev)->tx.delivered_mstamp)) TCP_SKB_CB(prev)->tx.delivered_mstamp = 0; tcp_rtx_queue_unlink_and_free(skb, sk); NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKMERGED); return true; } /* I wish gso_size would have a bit more sane initialization than * something-or-zero which complicates things */ static int tcp_skb_seglen(const struct sk_buff *skb) { return tcp_skb_pcount(skb) == 1 ? skb->len : tcp_skb_mss(skb); } /* Shifting pages past head area doesn't work */ static int skb_can_shift(const struct sk_buff *skb) { return !skb_headlen(skb) && skb_is_nonlinear(skb); } int tcp_skb_shift(struct sk_buff *to, struct sk_buff *from, int pcount, int shiftlen) { /* TCP min gso_size is 8 bytes (TCP_MIN_GSO_SIZE) * Since TCP_SKB_CB(skb)->tcp_gso_segs is 16 bits, we need * to make sure not storing more than 65535 * 8 bytes per skb, * even if current MSS is bigger. */ if (unlikely(to->len + shiftlen >= 65535 * TCP_MIN_GSO_SIZE)) return 0; if (unlikely(tcp_skb_pcount(to) + pcount > 65535)) return 0; return skb_shift(to, from, shiftlen); } /* Try collapsing SACK blocks spanning across multiple skbs to a single * skb. */ static struct sk_buff *tcp_shift_skb_data(struct sock *sk, struct sk_buff *skb, struct tcp_sacktag_state *state, u32 start_seq, u32 end_seq, bool dup_sack) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *prev; int mss; int pcount = 0; int len; int in_sack; /* Normally R but no L won't result in plain S */ if (!dup_sack && (TCP_SKB_CB(skb)->sacked & (TCPCB_LOST|TCPCB_SACKED_RETRANS)) == TCPCB_SACKED_RETRANS) goto fallback; if (!skb_can_shift(skb)) goto fallback; /* This frame is about to be dropped (was ACKed). */ if (!after(TCP_SKB_CB(skb)->end_seq, tp->snd_una)) goto fallback; /* Can only happen with delayed DSACK + discard craziness */ prev = skb_rb_prev(skb); if (!prev) goto fallback; if ((TCP_SKB_CB(prev)->sacked & TCPCB_TAGBITS) != TCPCB_SACKED_ACKED) goto fallback; if (!tcp_skb_can_collapse(prev, skb)) goto fallback; in_sack = !after(start_seq, TCP_SKB_CB(skb)->seq) && !before(end_seq, TCP_SKB_CB(skb)->end_seq); if (in_sack) { len = skb->len; pcount = tcp_skb_pcount(skb); mss = tcp_skb_seglen(skb); /* TODO: Fix DSACKs to not fragment already SACKed and we can * drop this restriction as unnecessary */ if (mss != tcp_skb_seglen(prev)) goto fallback; } else { if (!after(TCP_SKB_CB(skb)->end_seq, start_seq)) goto noop; /* CHECKME: This is non-MSS split case only?, this will * cause skipped skbs due to advancing loop btw, original * has that feature too */ if (tcp_skb_pcount(skb) <= 1) goto noop; in_sack = !after(start_seq, TCP_SKB_CB(skb)->seq); if (!in_sack) { /* TODO: head merge to next could be attempted here * if (!after(TCP_SKB_CB(skb)->end_seq, end_seq)), * though it might not be worth of the additional hassle * * ...we can probably just fallback to what was done * previously. We could try merging non-SACKed ones * as well but it probably isn't going to buy off * because later SACKs might again split them, and * it would make skb timestamp tracking considerably * harder problem. */ goto fallback; } len = end_seq - TCP_SKB_CB(skb)->seq; BUG_ON(len < 0); BUG_ON(len > skb->len); /* MSS boundaries should be honoured or else pcount will * severely break even though it makes things bit trickier. * Optimize common case to avoid most of the divides */ mss = tcp_skb_mss(skb); /* TODO: Fix DSACKs to not fragment already SACKed and we can * drop this restriction as unnecessary */ if (mss != tcp_skb_seglen(prev)) goto fallback; if (len == mss) { pcount = 1; } else if (len < mss) { goto noop; } else { pcount = len / mss; len = pcount * mss; } } /* tcp_sacktag_one() won't SACK-tag ranges below snd_una */ if (!after(TCP_SKB_CB(skb)->seq + len, tp->snd_una)) goto fallback; if (!tcp_skb_shift(prev, skb, pcount, len)) goto fallback; if (!tcp_shifted_skb(sk, prev, skb, state, pcount, len, mss, dup_sack)) goto out; /* Hole filled allows collapsing with the next as well, this is very * useful when hole on every nth skb pattern happens */ skb = skb_rb_next(prev); if (!skb) goto out; if (!skb_can_shift(skb) || ((TCP_SKB_CB(skb)->sacked & TCPCB_TAGBITS) != TCPCB_SACKED_ACKED) || (mss != tcp_skb_seglen(skb))) goto out; if (!tcp_skb_can_collapse(prev, skb)) goto out; len = skb->len; pcount = tcp_skb_pcount(skb); if (tcp_skb_shift(prev, skb, pcount, len)) tcp_shifted_skb(sk, prev, skb, state, pcount, len, mss, 0); out: return prev; noop: return skb; fallback: NET_INC_STATS(sock_net(sk), LINUX_MIB_SACKSHIFTFALLBACK); return NULL; } static struct sk_buff *tcp_sacktag_walk(struct sk_buff *skb, struct sock *sk, struct tcp_sack_block *next_dup, struct tcp_sacktag_state *state, u32 start_seq, u32 end_seq, bool dup_sack_in) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *tmp; skb_rbtree_walk_from(skb) { int in_sack = 0; bool dup_sack = dup_sack_in; /* queue is in-order => we can short-circuit the walk early */ if (!before(TCP_SKB_CB(skb)->seq, end_seq)) break; if (next_dup && before(TCP_SKB_CB(skb)->seq, next_dup->end_seq)) { in_sack = tcp_match_skb_to_sack(sk, skb, next_dup->start_seq, next_dup->end_seq); if (in_sack > 0) dup_sack = true; } /* skb reference here is a bit tricky to get right, since * shifting can eat and free both this skb and the next, * so not even _safe variant of the loop is enough. */ if (in_sack <= 0) { tmp = tcp_shift_skb_data(sk, skb, state, start_seq, end_seq, dup_sack); if (tmp) { if (tmp != skb) { skb = tmp; continue; } in_sack = 0; } else { in_sack = tcp_match_skb_to_sack(sk, skb, start_seq, end_seq); } } if (unlikely(in_sack < 0)) break; if (in_sack) { TCP_SKB_CB(skb)->sacked = tcp_sacktag_one(sk, state, TCP_SKB_CB(skb)->sacked, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq, dup_sack, tcp_skb_pcount(skb), tcp_skb_timestamp_us(skb)); tcp_rate_skb_delivered(sk, skb, state->rate); if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) list_del_init(&skb->tcp_tsorted_anchor); if (!before(TCP_SKB_CB(skb)->seq, tcp_highest_sack_seq(tp))) tcp_advance_highest_sack(sk, skb); } } return skb; } static struct sk_buff *tcp_sacktag_bsearch(struct sock *sk, u32 seq) { struct rb_node *parent, **p = &sk->tcp_rtx_queue.rb_node; struct sk_buff *skb; while (*p) { parent = *p; skb = rb_to_skb(parent); if (before(seq, TCP_SKB_CB(skb)->seq)) { p = &parent->rb_left; continue; } if (!before(seq, TCP_SKB_CB(skb)->end_seq)) { p = &parent->rb_right; continue; } return skb; } return NULL; } static struct sk_buff *tcp_sacktag_skip(struct sk_buff *skb, struct sock *sk, u32 skip_to_seq) { if (skb && after(TCP_SKB_CB(skb)->seq, skip_to_seq)) return skb; return tcp_sacktag_bsearch(sk, skip_to_seq); } static struct sk_buff *tcp_maybe_skipping_dsack(struct sk_buff *skb, struct sock *sk, struct tcp_sack_block *next_dup, struct tcp_sacktag_state *state, u32 skip_to_seq) { if (!next_dup) return skb; if (before(next_dup->start_seq, skip_to_seq)) { skb = tcp_sacktag_skip(skb, sk, next_dup->start_seq); skb = tcp_sacktag_walk(skb, sk, NULL, state, next_dup->start_seq, next_dup->end_seq, 1); } return skb; } static int tcp_sack_cache_ok(const struct tcp_sock *tp, const struct tcp_sack_block *cache) { return cache < tp->recv_sack_cache + ARRAY_SIZE(tp->recv_sack_cache); } static int tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb, u32 prior_snd_una, struct tcp_sacktag_state *state) { struct tcp_sock *tp = tcp_sk(sk); const unsigned char *ptr = (skb_transport_header(ack_skb) + TCP_SKB_CB(ack_skb)->sacked); struct tcp_sack_block_wire *sp_wire = (struct tcp_sack_block_wire *)(ptr+2); struct tcp_sack_block sp[TCP_NUM_SACKS]; struct tcp_sack_block *cache; struct sk_buff *skb; int num_sacks = min(TCP_NUM_SACKS, (ptr[1] - TCPOLEN_SACK_BASE) >> 3); int used_sacks; bool found_dup_sack = false; int i, j; int first_sack_index; state->flag = 0; state->reord = tp->snd_nxt; if (!tp->sacked_out) tcp_highest_sack_reset(sk); found_dup_sack = tcp_check_dsack(sk, ack_skb, sp_wire, num_sacks, prior_snd_una, state); /* Eliminate too old ACKs, but take into * account more or less fresh ones, they can * contain valid SACK info. */ if (before(TCP_SKB_CB(ack_skb)->ack_seq, prior_snd_una - tp->max_window)) return 0; if (!tp->packets_out) goto out; used_sacks = 0; first_sack_index = 0; for (i = 0; i < num_sacks; i++) { bool dup_sack = !i && found_dup_sack; sp[used_sacks].start_seq = get_unaligned_be32(&sp_wire[i].start_seq); sp[used_sacks].end_seq = get_unaligned_be32(&sp_wire[i].end_seq); if (!tcp_is_sackblock_valid(tp, dup_sack, sp[used_sacks].start_seq, sp[used_sacks].end_seq)) { int mib_idx; if (dup_sack) { if (!tp->undo_marker) mib_idx = LINUX_MIB_TCPDSACKIGNOREDNOUNDO; else mib_idx = LINUX_MIB_TCPDSACKIGNOREDOLD; } else { /* Don't count olds caused by ACK reordering */ if ((TCP_SKB_CB(ack_skb)->ack_seq != tp->snd_una) && !after(sp[used_sacks].end_seq, tp->snd_una)) continue; mib_idx = LINUX_MIB_TCPSACKDISCARD; } NET_INC_STATS(sock_net(sk), mib_idx); if (i == 0) first_sack_index = -1; continue; } /* Ignore very old stuff early */ if (!after(sp[used_sacks].end_seq, prior_snd_una)) { if (i == 0) first_sack_index = -1; continue; } used_sacks++; } /* order SACK blocks to allow in order walk of the retrans queue */ for (i = used_sacks - 1; i > 0; i--) { for (j = 0; j < i; j++) { if (after(sp[j].start_seq, sp[j + 1].start_seq)) { swap(sp[j], sp[j + 1]); /* Track where the first SACK block goes to */ if (j == first_sack_index) first_sack_index = j + 1; } } } state->mss_now = tcp_current_mss(sk); skb = NULL; i = 0; if (!tp->sacked_out) { /* It's already past, so skip checking against it */ cache = tp->recv_sack_cache + ARRAY_SIZE(tp->recv_sack_cache); } else { cache = tp->recv_sack_cache; /* Skip empty blocks in at head of the cache */ while (tcp_sack_cache_ok(tp, cache) && !cache->start_seq && !cache->end_seq) cache++; } while (i < used_sacks) { u32 start_seq = sp[i].start_seq; u32 end_seq = sp[i].end_seq; bool dup_sack = (found_dup_sack && (i == first_sack_index)); struct tcp_sack_block *next_dup = NULL; if (found_dup_sack && ((i + 1) == first_sack_index)) next_dup = &sp[i + 1]; /* Skip too early cached blocks */ while (tcp_sack_cache_ok(tp, cache) && !before(start_seq, cache->end_seq)) cache++; /* Can skip some work by looking recv_sack_cache? */ if (tcp_sack_cache_ok(tp, cache) && !dup_sack && after(end_seq, cache->start_seq)) { /* Head todo? */ if (before(start_seq, cache->start_seq)) { skb = tcp_sacktag_skip(skb, sk, start_seq); skb = tcp_sacktag_walk(skb, sk, next_dup, state, start_seq, cache->start_seq, dup_sack); } /* Rest of the block already fully processed? */ if (!after(end_seq, cache->end_seq)) goto advance_sp; skb = tcp_maybe_skipping_dsack(skb, sk, next_dup, state, cache->end_seq); /* ...tail remains todo... */ if (tcp_highest_sack_seq(tp) == cache->end_seq) { /* ...but better entrypoint exists! */ skb = tcp_highest_sack(sk); if (!skb) break; cache++; goto walk; } skb = tcp_sacktag_skip(skb, sk, cache->end_seq); /* Check overlap against next cached too (past this one already) */ cache++; continue; } if (!before(start_seq, tcp_highest_sack_seq(tp))) { skb = tcp_highest_sack(sk); if (!skb) break; } skb = tcp_sacktag_skip(skb, sk, start_seq); walk: skb = tcp_sacktag_walk(skb, sk, next_dup, state, start_seq, end_seq, dup_sack); advance_sp: i++; } /* Clear the head of the cache sack blocks so we can skip it next time */ for (i = 0; i < ARRAY_SIZE(tp->recv_sack_cache) - used_sacks; i++) { tp->recv_sack_cache[i].start_seq = 0; tp->recv_sack_cache[i].end_seq = 0; } for (j = 0; j < used_sacks; j++) tp->recv_sack_cache[i++] = sp[j]; if (inet_csk(sk)->icsk_ca_state != TCP_CA_Loss || tp->undo_marker) tcp_check_sack_reordering(sk, state->reord, 0); tcp_verify_left_out(tp); out: #if FASTRETRANS_DEBUG > 0 WARN_ON((int)tp->sacked_out < 0); WARN_ON((int)tp->lost_out < 0); WARN_ON((int)tp->retrans_out < 0); WARN_ON((int)tcp_packets_in_flight(tp) < 0); #endif return state->flag; } /* Limits sacked_out so that sum with lost_out isn't ever larger than * packets_out. Returns false if sacked_out adjustement wasn't necessary. */ static bool tcp_limit_reno_sacked(struct tcp_sock *tp) { u32 holes; holes = max(tp->lost_out, 1U); holes = min(holes, tp->packets_out); if ((tp->sacked_out + holes) > tp->packets_out) { tp->sacked_out = tp->packets_out - holes; return true; } return false; } /* If we receive more dupacks than we expected counting segments * in assumption of absent reordering, interpret this as reordering. * The only another reason could be bug in receiver TCP. */ static void tcp_check_reno_reordering(struct sock *sk, const int addend) { struct tcp_sock *tp = tcp_sk(sk); if (!tcp_limit_reno_sacked(tp)) return; tp->reordering = min_t(u32, tp->packets_out + addend, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_max_reordering)); tp->reord_seen++; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRENOREORDER); } /* Emulate SACKs for SACKless connection: account for a new dupack. */ static void tcp_add_reno_sack(struct sock *sk, int num_dupack, bool ece_ack) { if (num_dupack) { struct tcp_sock *tp = tcp_sk(sk); u32 prior_sacked = tp->sacked_out; s32 delivered; tp->sacked_out += num_dupack; tcp_check_reno_reordering(sk, 0); delivered = tp->sacked_out - prior_sacked; if (delivered > 0) tcp_count_delivered(tp, delivered, ece_ack); tcp_verify_left_out(tp); } } /* Account for ACK, ACKing some data in Reno Recovery phase. */ static void tcp_remove_reno_sacks(struct sock *sk, int acked, bool ece_ack) { struct tcp_sock *tp = tcp_sk(sk); if (acked > 0) { /* One ACK acked hole. The rest eat duplicate ACKs. */ tcp_count_delivered(tp, max_t(int, acked - tp->sacked_out, 1), ece_ack); if (acked - 1 >= tp->sacked_out) tp->sacked_out = 0; else tp->sacked_out -= acked - 1; } tcp_check_reno_reordering(sk, acked); tcp_verify_left_out(tp); } static inline void tcp_reset_reno_sack(struct tcp_sock *tp) { tp->sacked_out = 0; } void tcp_clear_retrans(struct tcp_sock *tp) { tp->retrans_out = 0; tp->lost_out = 0; tp->undo_marker = 0; tp->undo_retrans = -1; tp->sacked_out = 0; } static inline void tcp_init_undo(struct tcp_sock *tp) { tp->undo_marker = tp->snd_una; /* Retransmission still in flight may cause DSACKs later. */ tp->undo_retrans = tp->retrans_out ? : -1; } static bool tcp_is_rack(const struct sock *sk) { return READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_recovery) & TCP_RACK_LOSS_DETECTION; } /* If we detect SACK reneging, forget all SACK information * and reset tags completely, otherwise preserve SACKs. If receiver * dropped its ofo queue, we will know this due to reneging detection. */ static void tcp_timeout_mark_lost(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb, *head; bool is_reneg; /* is receiver reneging on SACKs? */ head = tcp_rtx_queue_head(sk); is_reneg = head && (TCP_SKB_CB(head)->sacked & TCPCB_SACKED_ACKED); if (is_reneg) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSACKRENEGING); tp->sacked_out = 0; /* Mark SACK reneging until we recover from this loss event. */ tp->is_sack_reneg = 1; } else if (tcp_is_reno(tp)) { tcp_reset_reno_sack(tp); } skb = head; skb_rbtree_walk_from(skb) { if (is_reneg) TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_ACKED; else if (tcp_is_rack(sk) && skb != head && tcp_rack_skb_timeout(tp, skb, 0) > 0) continue; /* Don't mark recently sent ones lost yet */ tcp_mark_skb_lost(sk, skb); } tcp_verify_left_out(tp); tcp_clear_all_retrans_hints(tp); } /* Enter Loss state. */ void tcp_enter_loss(struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); bool new_recovery = icsk->icsk_ca_state < TCP_CA_Recovery; u8 reordering; tcp_timeout_mark_lost(sk); /* Reduce ssthresh if it has not yet been made inside this window. */ if (icsk->icsk_ca_state <= TCP_CA_Disorder || !after(tp->high_seq, tp->snd_una) || (icsk->icsk_ca_state == TCP_CA_Loss && !icsk->icsk_retransmits)) { tp->prior_ssthresh = tcp_current_ssthresh(sk); tp->prior_cwnd = tcp_snd_cwnd(tp); tp->snd_ssthresh = icsk->icsk_ca_ops->ssthresh(sk); tcp_ca_event(sk, CA_EVENT_LOSS); tcp_init_undo(tp); } tcp_snd_cwnd_set(tp, tcp_packets_in_flight(tp) + 1); tp->snd_cwnd_cnt = 0; tp->snd_cwnd_stamp = tcp_jiffies32; /* Timeout in disordered state after receiving substantial DUPACKs * suggests that the degree of reordering is over-estimated. */ reordering = READ_ONCE(net->ipv4.sysctl_tcp_reordering); if (icsk->icsk_ca_state <= TCP_CA_Disorder && tp->sacked_out >= reordering) tp->reordering = min_t(unsigned int, tp->reordering, reordering); tcp_set_ca_state(sk, TCP_CA_Loss); tp->high_seq = tp->snd_nxt; tcp_ecn_queue_cwr(tp); /* F-RTO RFC5682 sec 3.1 step 1: retransmit SND.UNA if no previous * loss recovery is underway except recurring timeout(s) on * the same SND.UNA (sec 3.2). Disable F-RTO on path MTU probing */ tp->frto = READ_ONCE(net->ipv4.sysctl_tcp_frto) && (new_recovery || icsk->icsk_retransmits) && !inet_csk(sk)->icsk_mtup.probe_size; } /* If ACK arrived pointing to a remembered SACK, it means that our * remembered SACKs do not reflect real state of receiver i.e. * receiver _host_ is heavily congested (or buggy). * * To avoid big spurious retransmission bursts due to transient SACK * scoreboard oddities that look like reneging, we give the receiver a * little time (max(RTT/2, 10ms)) to send us some more ACKs that will * restore sanity to the SACK scoreboard. If the apparent reneging * persists until this RTO then we'll clear the SACK scoreboard. */ static bool tcp_check_sack_reneging(struct sock *sk, int flag) { if (flag & FLAG_SACK_RENEGING && flag & FLAG_SND_UNA_ADVANCED) { struct tcp_sock *tp = tcp_sk(sk); unsigned long delay = max(usecs_to_jiffies(tp->srtt_us >> 4), msecs_to_jiffies(10)); inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, delay, TCP_RTO_MAX); return true; } return false; } /* Heurestics to calculate number of duplicate ACKs. There's no dupACKs * counter when SACK is enabled (without SACK, sacked_out is used for * that purpose). * * With reordering, holes may still be in flight, so RFC3517 recovery * uses pure sacked_out (total number of SACKed segments) even though * it violates the RFC that uses duplicate ACKs, often these are equal * but when e.g. out-of-window ACKs or packet duplication occurs, * they differ. Since neither occurs due to loss, TCP should really * ignore them. */ static inline int tcp_dupack_heuristics(const struct tcp_sock *tp) { return tp->sacked_out + 1; } /* Linux NewReno/SACK/ECN state machine. * -------------------------------------- * * "Open" Normal state, no dubious events, fast path. * "Disorder" In all the respects it is "Open", * but requires a bit more attention. It is entered when * we see some SACKs or dupacks. It is split of "Open" * mainly to move some processing from fast path to slow one. * "CWR" CWND was reduced due to some Congestion Notification event. * It can be ECN, ICMP source quench, local device congestion. * "Recovery" CWND was reduced, we are fast-retransmitting. * "Loss" CWND was reduced due to RTO timeout or SACK reneging. * * tcp_fastretrans_alert() is entered: * - each incoming ACK, if state is not "Open" * - when arrived ACK is unusual, namely: * * SACK * * Duplicate ACK. * * ECN ECE. * * Counting packets in flight is pretty simple. * * in_flight = packets_out - left_out + retrans_out * * packets_out is SND.NXT-SND.UNA counted in packets. * * retrans_out is number of retransmitted segments. * * left_out is number of segments left network, but not ACKed yet. * * left_out = sacked_out + lost_out * * sacked_out: Packets, which arrived to receiver out of order * and hence not ACKed. With SACKs this number is simply * amount of SACKed data. Even without SACKs * it is easy to give pretty reliable estimate of this number, * counting duplicate ACKs. * * lost_out: Packets lost by network. TCP has no explicit * "loss notification" feedback from network (for now). * It means that this number can be only _guessed_. * Actually, it is the heuristics to predict lossage that * distinguishes different algorithms. * * F.e. after RTO, when all the queue is considered as lost, * lost_out = packets_out and in_flight = retrans_out. * * Essentially, we have now a few algorithms detecting * lost packets. * * If the receiver supports SACK: * * RFC6675/3517: It is the conventional algorithm. A packet is * considered lost if the number of higher sequence packets * SACKed is greater than or equal the DUPACK thoreshold * (reordering). This is implemented in tcp_mark_head_lost and * tcp_update_scoreboard. * * RACK (draft-ietf-tcpm-rack-01): it is a newer algorithm * (2017-) that checks timing instead of counting DUPACKs. * Essentially a packet is considered lost if it's not S/ACKed * after RTT + reordering_window, where both metrics are * dynamically measured and adjusted. This is implemented in * tcp_rack_mark_lost. * * If the receiver does not support SACK: * * NewReno (RFC6582): in Recovery we assume that one segment * is lost (classic Reno). While we are in Recovery and * a partial ACK arrives, we assume that one more packet * is lost (NewReno). This heuristics are the same in NewReno * and SACK. * * Really tricky (and requiring careful tuning) part of algorithm * is hidden in functions tcp_time_to_recover() and tcp_xmit_retransmit_queue(). * The first determines the moment _when_ we should reduce CWND and, * hence, slow down forward transmission. In fact, it determines the moment * when we decide that hole is caused by loss, rather than by a reorder. * * tcp_xmit_retransmit_queue() decides, _what_ we should retransmit to fill * holes, caused by lost packets. * * And the most logically complicated part of algorithm is undo * heuristics. We detect false retransmits due to both too early * fast retransmit (reordering) and underestimated RTO, analyzing * timestamps and D-SACKs. When we detect that some segments were * retransmitted by mistake and CWND reduction was wrong, we undo * window reduction and abort recovery phase. This logic is hidden * inside several functions named tcp_try_undo_<something>. */ /* This function decides, when we should leave Disordered state * and enter Recovery phase, reducing congestion window. * * Main question: may we further continue forward transmission * with the same cwnd? */ static bool tcp_time_to_recover(struct sock *sk, int flag) { struct tcp_sock *tp = tcp_sk(sk); /* Trick#1: The loss is proven. */ if (tp->lost_out) return true; /* Not-A-Trick#2 : Classic rule... */ if (!tcp_is_rack(sk) && tcp_dupack_heuristics(tp) > tp->reordering) return true; return false; } /* Detect loss in event "A" above by marking head of queue up as lost. * For RFC3517 SACK, a segment is considered lost if it * has at least tp->reordering SACKed seqments above it; "packets" refers to * the maximum SACKed segments to pass before reaching this limit. */ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; int cnt; /* Use SACK to deduce losses of new sequences sent during recovery */ const u32 loss_high = tp->snd_nxt; WARN_ON(packets > tp->packets_out); skb = tp->lost_skb_hint; if (skb) { /* Head already handled? */ if (mark_head && after(TCP_SKB_CB(skb)->seq, tp->snd_una)) return; cnt = tp->lost_cnt_hint; } else { skb = tcp_rtx_queue_head(sk); cnt = 0; } skb_rbtree_walk_from(skb) { /* TODO: do this better */ /* this is not the most efficient way to do this... */ tp->lost_skb_hint = skb; tp->lost_cnt_hint = cnt; if (after(TCP_SKB_CB(skb)->end_seq, loss_high)) break; if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) cnt += tcp_skb_pcount(skb); if (cnt > packets) break; if (!(TCP_SKB_CB(skb)->sacked & TCPCB_LOST)) tcp_mark_skb_lost(sk, skb); if (mark_head) break; } tcp_verify_left_out(tp); } /* Account newly detected lost packet(s) */ static void tcp_update_scoreboard(struct sock *sk, int fast_rexmit) { struct tcp_sock *tp = tcp_sk(sk); if (tcp_is_sack(tp)) { int sacked_upto = tp->sacked_out - tp->reordering; if (sacked_upto >= 0) tcp_mark_head_lost(sk, sacked_upto, 0); else if (fast_rexmit) tcp_mark_head_lost(sk, 1, 1); } } static bool tcp_tsopt_ecr_before(const struct tcp_sock *tp, u32 when) { return tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr && before(tp->rx_opt.rcv_tsecr, when); } /* skb is spurious retransmitted if the returned timestamp echo * reply is prior to the skb transmission time */ static bool tcp_skb_spurious_retrans(const struct tcp_sock *tp, const struct sk_buff *skb) { return (TCP_SKB_CB(skb)->sacked & TCPCB_RETRANS) && tcp_tsopt_ecr_before(tp, tcp_skb_timestamp(skb)); } /* Nothing was retransmitted or returned timestamp is less * than timestamp of the first retransmission. */ static inline bool tcp_packet_delayed(const struct tcp_sock *tp) { return tp->retrans_stamp && tcp_tsopt_ecr_before(tp, tp->retrans_stamp); } /* Undo procedures. */ /* We can clear retrans_stamp when there are no retransmissions in the * window. It would seem that it is trivially available for us in * tp->retrans_out, however, that kind of assumptions doesn't consider * what will happen if errors occur when sending retransmission for the * second time. ...It could the that such segment has only * TCPCB_EVER_RETRANS set at the present time. It seems that checking * the head skb is enough except for some reneging corner cases that * are not worth the effort. * * Main reason for all this complexity is the fact that connection dying * time now depends on the validity of the retrans_stamp, in particular, * that successive retransmissions of a segment must not advance * retrans_stamp under any conditions. */ static bool tcp_any_retrans_done(const struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; if (tp->retrans_out) return true; skb = tcp_rtx_queue_head(sk); if (unlikely(skb && TCP_SKB_CB(skb)->sacked & TCPCB_EVER_RETRANS)) return true; return false; } static void DBGUNDO(struct sock *sk, const char *msg) { #if FASTRETRANS_DEBUG > 1 struct tcp_sock *tp = tcp_sk(sk); struct inet_sock *inet = inet_sk(sk); if (sk->sk_family == AF_INET) { pr_debug("Undo %s %pI4/%u c%u l%u ss%u/%u p%u\n", msg, &inet->inet_daddr, ntohs(inet->inet_dport), tcp_snd_cwnd(tp), tcp_left_out(tp), tp->snd_ssthresh, tp->prior_ssthresh, tp->packets_out); } #if IS_ENABLED(CONFIG_IPV6) else if (sk->sk_family == AF_INET6) { pr_debug("Undo %s %pI6/%u c%u l%u ss%u/%u p%u\n", msg, &sk->sk_v6_daddr, ntohs(inet->inet_dport), tcp_snd_cwnd(tp), tcp_left_out(tp), tp->snd_ssthresh, tp->prior_ssthresh, tp->packets_out); } #endif #endif } static void tcp_undo_cwnd_reduction(struct sock *sk, bool unmark_loss) { struct tcp_sock *tp = tcp_sk(sk); if (unmark_loss) { struct sk_buff *skb; skb_rbtree_walk(skb, &sk->tcp_rtx_queue) { TCP_SKB_CB(skb)->sacked &= ~TCPCB_LOST; } tp->lost_out = 0; tcp_clear_all_retrans_hints(tp); } if (tp->prior_ssthresh) { const struct inet_connection_sock *icsk = inet_csk(sk); tcp_snd_cwnd_set(tp, icsk->icsk_ca_ops->undo_cwnd(sk)); if (tp->prior_ssthresh > tp->snd_ssthresh) { tp->snd_ssthresh = tp->prior_ssthresh; tcp_ecn_withdraw_cwr(tp); } } tp->snd_cwnd_stamp = tcp_jiffies32; tp->undo_marker = 0; tp->rack.advanced = 1; /* Force RACK to re-exam losses */ } static inline bool tcp_may_undo(const struct tcp_sock *tp) { return tp->undo_marker && (!tp->undo_retrans || tcp_packet_delayed(tp)); } static bool tcp_is_non_sack_preventing_reopen(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); if (tp->snd_una == tp->high_seq && tcp_is_reno(tp)) { /* Hold old state until something *above* high_seq * is ACKed. For Reno it is MUST to prevent false * fast retransmits (RFC2582). SACK TCP is safe. */ if (!tcp_any_retrans_done(sk)) tp->retrans_stamp = 0; return true; } return false; } /* People celebrate: "We love our President!" */ static bool tcp_try_undo_recovery(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); if (tcp_may_undo(tp)) { int mib_idx; /* Happy end! We did not retransmit anything * or our original transmission succeeded. */ DBGUNDO(sk, inet_csk(sk)->icsk_ca_state == TCP_CA_Loss ? "loss" : "retrans"); tcp_undo_cwnd_reduction(sk, false); if (inet_csk(sk)->icsk_ca_state == TCP_CA_Loss) mib_idx = LINUX_MIB_TCPLOSSUNDO; else mib_idx = LINUX_MIB_TCPFULLUNDO; NET_INC_STATS(sock_net(sk), mib_idx); } else if (tp->rack.reo_wnd_persist) { tp->rack.reo_wnd_persist--; } if (tcp_is_non_sack_preventing_reopen(sk)) return true; tcp_set_ca_state(sk, TCP_CA_Open); tp->is_sack_reneg = 0; return false; } /* Try to undo cwnd reduction, because D-SACKs acked all retransmitted data */ static bool tcp_try_undo_dsack(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); if (tp->undo_marker && !tp->undo_retrans) { tp->rack.reo_wnd_persist = min(TCP_RACK_RECOVERY_THRESH, tp->rack.reo_wnd_persist + 1); DBGUNDO(sk, "D-SACK"); tcp_undo_cwnd_reduction(sk, false); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKUNDO); return true; } return false; } /* Undo during loss recovery after partial ACK or using F-RTO. */ static bool tcp_try_undo_loss(struct sock *sk, bool frto_undo) { struct tcp_sock *tp = tcp_sk(sk); if (frto_undo || tcp_may_undo(tp)) { tcp_undo_cwnd_reduction(sk, true); DBGUNDO(sk, "partial loss"); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPLOSSUNDO); if (frto_undo) NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSPURIOUSRTOS); inet_csk(sk)->icsk_retransmits = 0; if (tcp_is_non_sack_preventing_reopen(sk)) return true; if (frto_undo || tcp_is_sack(tp)) { tcp_set_ca_state(sk, TCP_CA_Open); tp->is_sack_reneg = 0; } return true; } return false; } /* The cwnd reduction in CWR and Recovery uses the PRR algorithm in RFC 6937. * It computes the number of packets to send (sndcnt) based on packets newly * delivered: * 1) If the packets in flight is larger than ssthresh, PRR spreads the * cwnd reductions across a full RTT. * 2) Otherwise PRR uses packet conservation to send as much as delivered. * But when SND_UNA is acked without further losses, * slow starts cwnd up to ssthresh to speed up the recovery. */ static void tcp_init_cwnd_reduction(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); tp->high_seq = tp->snd_nxt; tp->tlp_high_seq = 0; tp->snd_cwnd_cnt = 0; tp->prior_cwnd = tcp_snd_cwnd(tp); tp->prr_delivered = 0; tp->prr_out = 0; tp->snd_ssthresh = inet_csk(sk)->icsk_ca_ops->ssthresh(sk); tcp_ecn_queue_cwr(tp); } void tcp_cwnd_reduction(struct sock *sk, int newly_acked_sacked, int newly_lost, int flag) { struct tcp_sock *tp = tcp_sk(sk); int sndcnt = 0; int delta = tp->snd_ssthresh - tcp_packets_in_flight(tp); if (newly_acked_sacked <= 0 || WARN_ON_ONCE(!tp->prior_cwnd)) return; tp->prr_delivered += newly_acked_sacked; if (delta < 0) { u64 dividend = (u64)tp->snd_ssthresh * tp->prr_delivered + tp->prior_cwnd - 1; sndcnt = div_u64(dividend, tp->prior_cwnd) - tp->prr_out; } else { sndcnt = max_t(int, tp->prr_delivered - tp->prr_out, newly_acked_sacked); if (flag & FLAG_SND_UNA_ADVANCED && !newly_lost) sndcnt++; sndcnt = min(delta, sndcnt); } /* Force a fast retransmit upon entering fast recovery */ sndcnt = max(sndcnt, (tp->prr_out ? 0 : 1)); tcp_snd_cwnd_set(tp, tcp_packets_in_flight(tp) + sndcnt); } static inline void tcp_end_cwnd_reduction(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); if (inet_csk(sk)->icsk_ca_ops->cong_control) return; /* Reset cwnd to ssthresh in CWR or Recovery (unless it's undone) */ if (tp->snd_ssthresh < TCP_INFINITE_SSTHRESH && (inet_csk(sk)->icsk_ca_state == TCP_CA_CWR || tp->undo_marker)) { tcp_snd_cwnd_set(tp, tp->snd_ssthresh); tp->snd_cwnd_stamp = tcp_jiffies32; } tcp_ca_event(sk, CA_EVENT_COMPLETE_CWR); } /* Enter CWR state. Disable cwnd undo since congestion is proven with ECN */ void tcp_enter_cwr(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); tp->prior_ssthresh = 0; if (inet_csk(sk)->icsk_ca_state < TCP_CA_CWR) { tp->undo_marker = 0; tcp_init_cwnd_reduction(sk); tcp_set_ca_state(sk, TCP_CA_CWR); } } EXPORT_SYMBOL(tcp_enter_cwr); static void tcp_try_keep_open(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); int state = TCP_CA_Open; if (tcp_left_out(tp) || tcp_any_retrans_done(sk)) state = TCP_CA_Disorder; if (inet_csk(sk)->icsk_ca_state != state) { tcp_set_ca_state(sk, state); tp->high_seq = tp->snd_nxt; } } static void tcp_try_to_open(struct sock *sk, int flag) { struct tcp_sock *tp = tcp_sk(sk); tcp_verify_left_out(tp); if (!tcp_any_retrans_done(sk)) tp->retrans_stamp = 0; if (flag & FLAG_ECE) tcp_enter_cwr(sk); if (inet_csk(sk)->icsk_ca_state != TCP_CA_CWR) { tcp_try_keep_open(sk); } } static void tcp_mtup_probe_failed(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); icsk->icsk_mtup.search_high = icsk->icsk_mtup.probe_size - 1; icsk->icsk_mtup.probe_size = 0; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMTUPFAIL); } static void tcp_mtup_probe_success(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); u64 val; tp->prior_ssthresh = tcp_current_ssthresh(sk); val = (u64)tcp_snd_cwnd(tp) * tcp_mss_to_mtu(sk, tp->mss_cache); do_div(val, icsk->icsk_mtup.probe_size); DEBUG_NET_WARN_ON_ONCE((u32)val != val); tcp_snd_cwnd_set(tp, max_t(u32, 1U, val)); tp->snd_cwnd_cnt = 0; tp->snd_cwnd_stamp = tcp_jiffies32; tp->snd_ssthresh = tcp_current_ssthresh(sk); icsk->icsk_mtup.search_low = icsk->icsk_mtup.probe_size; icsk->icsk_mtup.probe_size = 0; tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMTUPSUCCESS); } /* Do a simple retransmit without using the backoff mechanisms in * tcp_timer. This is used for path mtu discovery. * The socket is already locked here. */ void tcp_simple_retransmit(struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; int mss; /* A fastopen SYN request is stored as two separate packets within * the retransmit queue, this is done by tcp_send_syn_data(). * As a result simply checking the MSS of the frames in the queue * will not work for the SYN packet. * * Us being here is an indication of a path MTU issue so we can * assume that the fastopen SYN was lost and just mark all the * frames in the retransmit queue as lost. We will use an MSS of * -1 to mark all frames as lost, otherwise compute the current MSS. */ if (tp->syn_data && sk->sk_state == TCP_SYN_SENT) mss = -1; else mss = tcp_current_mss(sk); skb_rbtree_walk(skb, &sk->tcp_rtx_queue) { if (tcp_skb_seglen(skb) > mss) tcp_mark_skb_lost(sk, skb); } tcp_clear_retrans_hints_partial(tp); if (!tp->lost_out) return; if (tcp_is_reno(tp)) tcp_limit_reno_sacked(tp); tcp_verify_left_out(tp); /* Don't muck with the congestion window here. * Reason is that we do not increase amount of _data_ * in network, but units changed and effective * cwnd/ssthresh really reduced now. */ if (icsk->icsk_ca_state != TCP_CA_Loss) { tp->high_seq = tp->snd_nxt; tp->snd_ssthresh = tcp_current_ssthresh(sk); tp->prior_ssthresh = 0; tp->undo_marker = 0; tcp_set_ca_state(sk, TCP_CA_Loss); } tcp_xmit_retransmit_queue(sk); } EXPORT_SYMBOL(tcp_simple_retransmit); void tcp_enter_recovery(struct sock *sk, bool ece_ack) { struct tcp_sock *tp = tcp_sk(sk); int mib_idx; if (tcp_is_reno(tp)) mib_idx = LINUX_MIB_TCPRENORECOVERY; else mib_idx = LINUX_MIB_TCPSACKRECOVERY; NET_INC_STATS(sock_net(sk), mib_idx); tp->prior_ssthresh = 0; tcp_init_undo(tp); if (!tcp_in_cwnd_reduction(sk)) { if (!ece_ack) tp->prior_ssthresh = tcp_current_ssthresh(sk); tcp_init_cwnd_reduction(sk); } tcp_set_ca_state(sk, TCP_CA_Recovery); } /* Process an ACK in CA_Loss state. Move to CA_Open if lost data are * recovered or spurious. Otherwise retransmits more on partial ACKs. */ static void tcp_process_loss(struct sock *sk, int flag, int num_dupack, int *rexmit) { struct tcp_sock *tp = tcp_sk(sk); bool recovered = !before(tp->snd_una, tp->high_seq); if ((flag & FLAG_SND_UNA_ADVANCED || rcu_access_pointer(tp->fastopen_rsk)) && tcp_try_undo_loss(sk, false)) return; if (tp->frto) { /* F-RTO RFC5682 sec 3.1 (sack enhanced version). */ /* Step 3.b. A timeout is spurious if not all data are * lost, i.e., never-retransmitted data are (s)acked. */ if ((flag & FLAG_ORIG_SACK_ACKED) && tcp_try_undo_loss(sk, true)) return; if (after(tp->snd_nxt, tp->high_seq)) { if (flag & FLAG_DATA_SACKED || num_dupack) tp->frto = 0; /* Step 3.a. loss was real */ } else if (flag & FLAG_SND_UNA_ADVANCED && !recovered) { tp->high_seq = tp->snd_nxt; /* Step 2.b. Try send new data (but deferred until cwnd * is updated in tcp_ack()). Otherwise fall back to * the conventional recovery. */ if (!tcp_write_queue_empty(sk) && after(tcp_wnd_end(tp), tp->snd_nxt)) { *rexmit = REXMIT_NEW; return; } tp->frto = 0; } } if (recovered) { /* F-RTO RFC5682 sec 3.1 step 2.a and 1st part of step 3.a */ tcp_try_undo_recovery(sk); return; } if (tcp_is_reno(tp)) { /* A Reno DUPACK means new data in F-RTO step 2.b above are * delivered. Lower inflight to clock out (re)transmissions. */ if (after(tp->snd_nxt, tp->high_seq) && num_dupack) tcp_add_reno_sack(sk, num_dupack, flag & FLAG_ECE); else if (flag & FLAG_SND_UNA_ADVANCED) tcp_reset_reno_sack(tp); } *rexmit = REXMIT_LOST; } static bool tcp_force_fast_retransmit(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); return after(tcp_highest_sack_seq(tp), tp->snd_una + tp->reordering * tp->mss_cache); } /* Undo during fast recovery after partial ACK. */ static bool tcp_try_undo_partial(struct sock *sk, u32 prior_snd_una, bool *do_lost) { struct tcp_sock *tp = tcp_sk(sk); if (tp->undo_marker && tcp_packet_delayed(tp)) { /* Plain luck! Hole if filled with delayed * packet, rather than with a retransmit. Check reordering. */ tcp_check_sack_reordering(sk, prior_snd_una, 1); /* We are getting evidence that the reordering degree is higher * than we realized. If there are no retransmits out then we * can undo. Otherwise we clock out new packets but do not * mark more packets lost or retransmit more. */ if (tp->retrans_out) return true; if (!tcp_any_retrans_done(sk)) tp->retrans_stamp = 0; DBGUNDO(sk, "partial recovery"); tcp_undo_cwnd_reduction(sk, true); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPARTIALUNDO); tcp_try_keep_open(sk); } else { /* Partial ACK arrived. Force fast retransmit. */ *do_lost = tcp_force_fast_retransmit(sk); } return false; } static void tcp_identify_packet_loss(struct sock *sk, int *ack_flag) { struct tcp_sock *tp = tcp_sk(sk); if (tcp_rtx_queue_empty(sk)) return; if (unlikely(tcp_is_reno(tp))) { tcp_newreno_mark_lost(sk, *ack_flag & FLAG_SND_UNA_ADVANCED); } else if (tcp_is_rack(sk)) { u32 prior_retrans = tp->retrans_out; if (tcp_rack_mark_lost(sk)) *ack_flag &= ~FLAG_SET_XMIT_TIMER; if (prior_retrans > tp->retrans_out) *ack_flag |= FLAG_LOST_RETRANS; } } /* Process an event, which can update packets-in-flight not trivially. * Main goal of this function is to calculate new estimate for left_out, * taking into account both packets sitting in receiver's buffer and * packets lost by network. * * Besides that it updates the congestion state when packet loss or ECN * is detected. But it does not reduce the cwnd, it is done by the * congestion control later. * * It does _not_ decide what to send, it is made in function * tcp_xmit_retransmit_queue(). */ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, int num_dupack, int *ack_flag, int *rexmit) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); int fast_rexmit = 0, flag = *ack_flag; bool ece_ack = flag & FLAG_ECE; bool do_lost = num_dupack || ((flag & FLAG_DATA_SACKED) && tcp_force_fast_retransmit(sk)); if (!tp->packets_out && tp->sacked_out) tp->sacked_out = 0; /* Now state machine starts. * A. ECE, hence prohibit cwnd undoing, the reduction is required. */ if (ece_ack) tp->prior_ssthresh = 0; /* B. In all the states check for reneging SACKs. */ if (tcp_check_sack_reneging(sk, flag)) return; /* C. Check consistency of the current state. */ tcp_verify_left_out(tp); /* D. Check state exit conditions. State can be terminated * when high_seq is ACKed. */ if (icsk->icsk_ca_state == TCP_CA_Open) { WARN_ON(tp->retrans_out != 0 && !tp->syn_data); tp->retrans_stamp = 0; } else if (!before(tp->snd_una, tp->high_seq)) { switch (icsk->icsk_ca_state) { case TCP_CA_CWR: /* CWR is to be held something *above* high_seq * is ACKed for CWR bit to reach receiver. */ if (tp->snd_una != tp->high_seq) { tcp_end_cwnd_reduction(sk); tcp_set_ca_state(sk, TCP_CA_Open); } break; case TCP_CA_Recovery: if (tcp_is_reno(tp)) tcp_reset_reno_sack(tp); if (tcp_try_undo_recovery(sk)) return; tcp_end_cwnd_reduction(sk); break; } } /* E. Process state. */ switch (icsk->icsk_ca_state) { case TCP_CA_Recovery: if (!(flag & FLAG_SND_UNA_ADVANCED)) { if (tcp_is_reno(tp)) tcp_add_reno_sack(sk, num_dupack, ece_ack); } else if (tcp_try_undo_partial(sk, prior_snd_una, &do_lost)) return; if (tcp_try_undo_dsack(sk)) tcp_try_keep_open(sk); tcp_identify_packet_loss(sk, ack_flag); if (icsk->icsk_ca_state != TCP_CA_Recovery) { if (!tcp_time_to_recover(sk, flag)) return; /* Undo reverts the recovery state. If loss is evident, * starts a new recovery (e.g. reordering then loss); */ tcp_enter_recovery(sk, ece_ack); } break; case TCP_CA_Loss: tcp_process_loss(sk, flag, num_dupack, rexmit); tcp_identify_packet_loss(sk, ack_flag); if (!(icsk->icsk_ca_state == TCP_CA_Open || (*ack_flag & FLAG_LOST_RETRANS))) return; /* Change state if cwnd is undone or retransmits are lost */ fallthrough; default: if (tcp_is_reno(tp)) { if (flag & FLAG_SND_UNA_ADVANCED) tcp_reset_reno_sack(tp); tcp_add_reno_sack(sk, num_dupack, ece_ack); } if (icsk->icsk_ca_state <= TCP_CA_Disorder) tcp_try_undo_dsack(sk); tcp_identify_packet_loss(sk, ack_flag); if (!tcp_time_to_recover(sk, flag)) { tcp_try_to_open(sk, flag); return; } /* MTU probe failure: don't reduce cwnd */ if (icsk->icsk_ca_state < TCP_CA_CWR && icsk->icsk_mtup.probe_size && tp->snd_una == tp->mtu_probe.probe_seq_start) { tcp_mtup_probe_failed(sk); /* Restores the reduction we did in tcp_mtup_probe() */ tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) + 1); tcp_simple_retransmit(sk); return; } /* Otherwise enter Recovery state */ tcp_enter_recovery(sk, ece_ack); fast_rexmit = 1; } if (!tcp_is_rack(sk) && do_lost) tcp_update_scoreboard(sk, fast_rexmit); *rexmit = REXMIT_LOST; } static void tcp_update_rtt_min(struct sock *sk, u32 rtt_us, const int flag) { u32 wlen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_min_rtt_wlen) * HZ; struct tcp_sock *tp = tcp_sk(sk); if ((flag & FLAG_ACK_MAYBE_DELAYED) && rtt_us > tcp_min_rtt(tp)) { /* If the remote keeps returning delayed ACKs, eventually * the min filter would pick it up and overestimate the * prop. delay when it expires. Skip suspected delayed ACKs. */ return; } minmax_running_min(&tp->rtt_min, wlen, tcp_jiffies32, rtt_us ? : jiffies_to_usecs(1)); } static bool tcp_ack_update_rtt(struct sock *sk, const int flag, long seq_rtt_us, long sack_rtt_us, long ca_rtt_us, struct rate_sample *rs) { const struct tcp_sock *tp = tcp_sk(sk); /* Prefer RTT measured from ACK's timing to TS-ECR. This is because * broken middle-boxes or peers may corrupt TS-ECR fields. But * Karn's algorithm forbids taking RTT if some retransmitted data * is acked (RFC6298). */ if (seq_rtt_us < 0) seq_rtt_us = sack_rtt_us; /* RTTM Rule: A TSecr value received in a segment is used to * update the averaged RTT measurement only if the segment * acknowledges some new data, i.e., only if it advances the * left edge of the send window. * See draft-ietf-tcplw-high-performance-00, section 3.3. */ if (seq_rtt_us < 0 && tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr && flag & FLAG_ACKED) { u32 delta = tcp_time_stamp(tp) - tp->rx_opt.rcv_tsecr; if (likely(delta < INT_MAX / (USEC_PER_SEC / TCP_TS_HZ))) { if (!delta) delta = 1; seq_rtt_us = delta * (USEC_PER_SEC / TCP_TS_HZ); ca_rtt_us = seq_rtt_us; } } rs->rtt_us = ca_rtt_us; /* RTT of last (S)ACKed packet (or -1) */ if (seq_rtt_us < 0) return false; /* ca_rtt_us >= 0 is counting on the invariant that ca_rtt_us is * always taken together with ACK, SACK, or TS-opts. Any negative * values will be skipped with the seq_rtt_us < 0 check above. */ tcp_update_rtt_min(sk, ca_rtt_us, flag); tcp_rtt_estimator(sk, seq_rtt_us); tcp_set_rto(sk); /* RFC6298: only reset backoff on valid RTT measurement. */ inet_csk(sk)->icsk_backoff = 0; return true; } /* Compute time elapsed between (last) SYNACK and the ACK completing 3WHS. */ void tcp_synack_rtt_meas(struct sock *sk, struct request_sock *req) { struct rate_sample rs; long rtt_us = -1L; if (req && !req->num_retrans && tcp_rsk(req)->snt_synack) rtt_us = tcp_stamp_us_delta(tcp_clock_us(), tcp_rsk(req)->snt_synack); tcp_ack_update_rtt(sk, FLAG_SYN_ACKED, rtt_us, -1L, rtt_us, &rs); } static void tcp_cong_avoid(struct sock *sk, u32 ack, u32 acked) { const struct inet_connection_sock *icsk = inet_csk(sk); icsk->icsk_ca_ops->cong_avoid(sk, ack, acked); tcp_sk(sk)->snd_cwnd_stamp = tcp_jiffies32; } /* Restart timer after forward progress on connection. * RFC2988 recommends to restart timer to now+rto. */ void tcp_rearm_rto(struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); /* If the retrans timer is currently being used by Fast Open * for SYN-ACK retrans purpose, stay put. */ if (rcu_access_pointer(tp->fastopen_rsk)) return; if (!tp->packets_out) { inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS); } else { u32 rto = inet_csk(sk)->icsk_rto; /* Offset the time elapsed after installing regular RTO */ if (icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { s64 delta_us = tcp_rto_delta_us(sk); /* delta_us may not be positive if the socket is locked * when the retrans timer fires and is rescheduled. */ rto = usecs_to_jiffies(max_t(int, delta_us, 1)); } tcp_reset_xmit_timer(sk, ICSK_TIME_RETRANS, rto, TCP_RTO_MAX); } } /* Try to schedule a loss probe; if that doesn't work, then schedule an RTO. */ static void tcp_set_xmit_timer(struct sock *sk) { if (!tcp_schedule_loss_probe(sk, true)) tcp_rearm_rto(sk); } /* If we get here, the whole TSO packet has not been acked. */ static u32 tcp_tso_acked(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); u32 packets_acked; BUG_ON(!after(TCP_SKB_CB(skb)->end_seq, tp->snd_una)); packets_acked = tcp_skb_pcount(skb); if (tcp_trim_head(sk, skb, tp->snd_una - TCP_SKB_CB(skb)->seq)) return 0; packets_acked -= tcp_skb_pcount(skb); if (packets_acked) { BUG_ON(tcp_skb_pcount(skb) == 0); BUG_ON(!before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq)); } return packets_acked; } static void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb, const struct sk_buff *ack_skb, u32 prior_snd_una) { const struct skb_shared_info *shinfo; /* Avoid cache line misses to get skb_shinfo() and shinfo->tx_flags */ if (likely(!TCP_SKB_CB(skb)->txstamp_ack)) return; shinfo = skb_shinfo(skb); if (!before(shinfo->tskey, prior_snd_una) && before(shinfo->tskey, tcp_sk(sk)->snd_una)) { tcp_skb_tsorted_save(skb) { __skb_tstamp_tx(skb, ack_skb, NULL, sk, SCM_TSTAMP_ACK); } tcp_skb_tsorted_restore(skb); } } /* Remove acknowledged frames from the retransmission queue. If our packet * is before the ack sequence we can discard it as it's confirmed to have * arrived at the other end. */ static int tcp_clean_rtx_queue(struct sock *sk, const struct sk_buff *ack_skb, u32 prior_fack, u32 prior_snd_una, struct tcp_sacktag_state *sack, bool ece_ack) { const struct inet_connection_sock *icsk = inet_csk(sk); u64 first_ackt, last_ackt; struct tcp_sock *tp = tcp_sk(sk); u32 prior_sacked = tp->sacked_out; u32 reord = tp->snd_nxt; /* lowest acked un-retx un-sacked seq */ struct sk_buff *skb, *next; bool fully_acked = true; long sack_rtt_us = -1L; long seq_rtt_us = -1L; long ca_rtt_us = -1L; u32 pkts_acked = 0; bool rtt_update; int flag = 0; first_ackt = 0; for (skb = skb_rb_first(&sk->tcp_rtx_queue); skb; skb = next) { struct tcp_skb_cb *scb = TCP_SKB_CB(skb); const u32 start_seq = scb->seq; u8 sacked = scb->sacked; u32 acked_pcount; /* Determine how many packets and what bytes were acked, tso and else */ if (after(scb->end_seq, tp->snd_una)) { if (tcp_skb_pcount(skb) == 1 || !after(tp->snd_una, scb->seq)) break; acked_pcount = tcp_tso_acked(sk, skb); if (!acked_pcount) break; fully_acked = false; } else { acked_pcount = tcp_skb_pcount(skb); } if (unlikely(sacked & TCPCB_RETRANS)) { if (sacked & TCPCB_SACKED_RETRANS) tp->retrans_out -= acked_pcount; flag |= FLAG_RETRANS_DATA_ACKED; } else if (!(sacked & TCPCB_SACKED_ACKED)) { last_ackt = tcp_skb_timestamp_us(skb); WARN_ON_ONCE(last_ackt == 0); if (!first_ackt) first_ackt = last_ackt; if (before(start_seq, reord)) reord = start_seq; if (!after(scb->end_seq, tp->high_seq)) flag |= FLAG_ORIG_SACK_ACKED; } if (sacked & TCPCB_SACKED_ACKED) { tp->sacked_out -= acked_pcount; } else if (tcp_is_sack(tp)) { tcp_count_delivered(tp, acked_pcount, ece_ack); if (!tcp_skb_spurious_retrans(tp, skb)) tcp_rack_advance(tp, sacked, scb->end_seq, tcp_skb_timestamp_us(skb)); } if (sacked & TCPCB_LOST) tp->lost_out -= acked_pcount; tp->packets_out -= acked_pcount; pkts_acked += acked_pcount; tcp_rate_skb_delivered(sk, skb, sack->rate); /* Initial outgoing SYN's get put onto the write_queue * just like anything else we transmit. It is not * true data, and if we misinform our callers that * this ACK acks real data, we will erroneously exit * connection startup slow start one packet too * quickly. This is severely frowned upon behavior. */ if (likely(!(scb->tcp_flags & TCPHDR_SYN))) { flag |= FLAG_DATA_ACKED; } else { flag |= FLAG_SYN_ACKED; tp->retrans_stamp = 0; } if (!fully_acked) break; tcp_ack_tstamp(sk, skb, ack_skb, prior_snd_una); next = skb_rb_next(skb); if (unlikely(skb == tp->retransmit_skb_hint)) tp->retransmit_skb_hint = NULL; if (unlikely(skb == tp->lost_skb_hint)) tp->lost_skb_hint = NULL; tcp_highest_sack_replace(sk, skb, next); tcp_rtx_queue_unlink_and_free(skb, sk); } if (!skb) tcp_chrono_stop(sk, TCP_CHRONO_BUSY); if (likely(between(tp->snd_up, prior_snd_una, tp->snd_una))) tp->snd_up = tp->snd_una; if (skb) { tcp_ack_tstamp(sk, skb, ack_skb, prior_snd_una); if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) flag |= FLAG_SACK_RENEGING; } if (likely(first_ackt) && !(flag & FLAG_RETRANS_DATA_ACKED)) { seq_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, first_ackt); ca_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, last_ackt); if (pkts_acked == 1 && fully_acked && !prior_sacked && (tp->snd_una - prior_snd_una) < tp->mss_cache && sack->rate->prior_delivered + 1 == tp->delivered && !(flag & (FLAG_CA_ALERT | FLAG_SYN_ACKED))) { /* Conservatively mark a delayed ACK. It's typically * from a lone runt packet over the round trip to * a receiver w/o out-of-order or CE events. */ flag |= FLAG_ACK_MAYBE_DELAYED; } } if (sack->first_sackt) { sack_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, sack->first_sackt); ca_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, sack->last_sackt); } rtt_update = tcp_ack_update_rtt(sk, flag, seq_rtt_us, sack_rtt_us, ca_rtt_us, sack->rate); if (flag & FLAG_ACKED) { flag |= FLAG_SET_XMIT_TIMER; /* set TLP or RTO timer */ if (unlikely(icsk->icsk_mtup.probe_size && !after(tp->mtu_probe.probe_seq_end, tp->snd_una))) { tcp_mtup_probe_success(sk); } if (tcp_is_reno(tp)) { tcp_remove_reno_sacks(sk, pkts_acked, ece_ack); /* If any of the cumulatively ACKed segments was * retransmitted, non-SACK case cannot confirm that * progress was due to original transmission due to * lack of TCPCB_SACKED_ACKED bits even if some of * the packets may have been never retransmitted. */ if (flag & FLAG_RETRANS_DATA_ACKED) flag &= ~FLAG_ORIG_SACK_ACKED; } else { int delta; /* Non-retransmitted hole got filled? That's reordering */ if (before(reord, prior_fack)) tcp_check_sack_reordering(sk, reord, 0); delta = prior_sacked - tp->sacked_out; tp->lost_cnt_hint -= min(tp->lost_cnt_hint, delta); } } else if (skb && rtt_update && sack_rtt_us >= 0 && sack_rtt_us > tcp_stamp_us_delta(tp->tcp_mstamp, tcp_skb_timestamp_us(skb))) { /* Do not re-arm RTO if the sack RTT is measured from data sent * after when the head was last (re)transmitted. Otherwise the * timeout may continue to extend in loss recovery. */ flag |= FLAG_SET_XMIT_TIMER; /* set TLP or RTO timer */ } if (icsk->icsk_ca_ops->pkts_acked) { struct ack_sample sample = { .pkts_acked = pkts_acked, .rtt_us = sack->rate->rtt_us }; sample.in_flight = tp->mss_cache * (tp->delivered - sack->rate->prior_delivered); icsk->icsk_ca_ops->pkts_acked(sk, &sample); } #if FASTRETRANS_DEBUG > 0 WARN_ON((int)tp->sacked_out < 0); WARN_ON((int)tp->lost_out < 0); WARN_ON((int)tp->retrans_out < 0); if (!tp->packets_out && tcp_is_sack(tp)) { icsk = inet_csk(sk); if (tp->lost_out) { pr_debug("Leak l=%u %d\n", tp->lost_out, icsk->icsk_ca_state); tp->lost_out = 0; } if (tp->sacked_out) { pr_debug("Leak s=%u %d\n", tp->sacked_out, icsk->icsk_ca_state); tp->sacked_out = 0; } if (tp->retrans_out) { pr_debug("Leak r=%u %d\n", tp->retrans_out, icsk->icsk_ca_state); tp->retrans_out = 0; } } #endif return flag; } static void tcp_ack_probe(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct sk_buff *head = tcp_send_head(sk); const struct tcp_sock *tp = tcp_sk(sk); /* Was it a usable window open? */ if (!head) return; if (!after(TCP_SKB_CB(head)->end_seq, tcp_wnd_end(tp))) { icsk->icsk_backoff = 0; icsk->icsk_probes_tstamp = 0; inet_csk_clear_xmit_timer(sk, ICSK_TIME_PROBE0); /* Socket must be waked up by subsequent tcp_data_snd_check(). * This function is not for random using! */ } else { unsigned long when = tcp_probe0_when(sk, TCP_RTO_MAX); when = tcp_clamp_probe0_to_user_timeout(sk, when); tcp_reset_xmit_timer(sk, ICSK_TIME_PROBE0, when, TCP_RTO_MAX); } } static inline bool tcp_ack_is_dubious(const struct sock *sk, const int flag) { return !(flag & FLAG_NOT_DUP) || (flag & FLAG_CA_ALERT) || inet_csk(sk)->icsk_ca_state != TCP_CA_Open; } /* Decide wheather to run the increase function of congestion control. */ static inline bool tcp_may_raise_cwnd(const struct sock *sk, const int flag) { /* If reordering is high then always grow cwnd whenever data is * delivered regardless of its ordering. Otherwise stay conservative * and only grow cwnd on in-order delivery (RFC5681). A stretched ACK w/ * new SACK or ECE mark may first advance cwnd here and later reduce * cwnd in tcp_fastretrans_alert() based on more states. */ if (tcp_sk(sk)->reordering > READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reordering)) return flag & FLAG_FORWARD_PROGRESS; return flag & FLAG_DATA_ACKED; } /* The "ultimate" congestion control function that aims to replace the rigid * cwnd increase and decrease control (tcp_cong_avoid,tcp_*cwnd_reduction). * It's called toward the end of processing an ACK with precise rate * information. All transmission or retransmission are delayed afterwards. */ static void tcp_cong_control(struct sock *sk, u32 ack, u32 acked_sacked, int flag, const struct rate_sample *rs) { const struct inet_connection_sock *icsk = inet_csk(sk); if (icsk->icsk_ca_ops->cong_control) { icsk->icsk_ca_ops->cong_control(sk, rs); return; } if (tcp_in_cwnd_reduction(sk)) { /* Reduce cwnd if state mandates */ tcp_cwnd_reduction(sk, acked_sacked, rs->losses, flag); } else if (tcp_may_raise_cwnd(sk, flag)) { /* Advance cwnd if state allows */ tcp_cong_avoid(sk, ack, acked_sacked); } tcp_update_pacing_rate(sk); } /* Check that window update is acceptable. * The function assumes that snd_una<=ack<=snd_next. */ static inline bool tcp_may_update_window(const struct tcp_sock *tp, const u32 ack, const u32 ack_seq, const u32 nwin) { return after(ack, tp->snd_una) || after(ack_seq, tp->snd_wl1) || (ack_seq == tp->snd_wl1 && (nwin > tp->snd_wnd || !nwin)); } /* If we update tp->snd_una, also update tp->bytes_acked */ static void tcp_snd_una_update(struct tcp_sock *tp, u32 ack) { u32 delta = ack - tp->snd_una; sock_owned_by_me((struct sock *)tp); tp->bytes_acked += delta; tp->snd_una = ack; } /* If we update tp->rcv_nxt, also update tp->bytes_received */ static void tcp_rcv_nxt_update(struct tcp_sock *tp, u32 seq) { u32 delta = seq - tp->rcv_nxt; sock_owned_by_me((struct sock *)tp); tp->bytes_received += delta; WRITE_ONCE(tp->rcv_nxt, seq); } /* Update our send window. * * Window update algorithm, described in RFC793/RFC1122 (used in linux-2.2 * and in FreeBSD. NetBSD's one is even worse.) is wrong. */ static int tcp_ack_update_window(struct sock *sk, const struct sk_buff *skb, u32 ack, u32 ack_seq) { struct tcp_sock *tp = tcp_sk(sk); int flag = 0; u32 nwin = ntohs(tcp_hdr(skb)->window); if (likely(!tcp_hdr(skb)->syn)) nwin <<= tp->rx_opt.snd_wscale; if (tcp_may_update_window(tp, ack, ack_seq, nwin)) { flag |= FLAG_WIN_UPDATE; tcp_update_wl(tp, ack_seq); if (tp->snd_wnd != nwin) { tp->snd_wnd = nwin; /* Note, it is the only place, where * fast path is recovered for sending TCP. */ tp->pred_flags = 0; tcp_fast_path_check(sk); if (!tcp_write_queue_empty(sk)) tcp_slow_start_after_idle_check(sk); if (nwin > tp->max_window) { tp->max_window = nwin; tcp_sync_mss(sk, inet_csk(sk)->icsk_pmtu_cookie); } } } tcp_snd_una_update(tp, ack); return flag; } static bool __tcp_oow_rate_limited(struct net *net, int mib_idx, u32 *last_oow_ack_time) { /* Paired with the WRITE_ONCE() in this function. */ u32 val = READ_ONCE(*last_oow_ack_time); if (val) { s32 elapsed = (s32)(tcp_jiffies32 - val); if (0 <= elapsed && elapsed < READ_ONCE(net->ipv4.sysctl_tcp_invalid_ratelimit)) { NET_INC_STATS(net, mib_idx); return true; /* rate-limited: don't send yet! */ } } /* Paired with the prior READ_ONCE() and with itself, * as we might be lockless. */ WRITE_ONCE(*last_oow_ack_time, tcp_jiffies32); return false; /* not rate-limited: go ahead, send dupack now! */ } /* Return true if we're currently rate-limiting out-of-window ACKs and * thus shouldn't send a dupack right now. We rate-limit dupacks in * response to out-of-window SYNs or ACKs to mitigate ACK loops or DoS * attacks that send repeated SYNs or ACKs for the same connection. To * do this, we do not send a duplicate SYNACK or ACK if the remote * endpoint is sending out-of-window SYNs or pure ACKs at a high rate. */ bool tcp_oow_rate_limited(struct net *net, const struct sk_buff *skb, int mib_idx, u32 *last_oow_ack_time) { /* Data packets without SYNs are not likely part of an ACK loop. */ if ((TCP_SKB_CB(skb)->seq != TCP_SKB_CB(skb)->end_seq) && !tcp_hdr(skb)->syn) return false; return __tcp_oow_rate_limited(net, mib_idx, last_oow_ack_time); } /* RFC 5961 7 [ACK Throttling] */ static void tcp_send_challenge_ack(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); u32 count, now, ack_limit; /* First check our per-socket dupack rate limit. */ if (__tcp_oow_rate_limited(net, LINUX_MIB_TCPACKSKIPPEDCHALLENGE, &tp->last_oow_ack_time)) return; ack_limit = READ_ONCE(net->ipv4.sysctl_tcp_challenge_ack_limit); if (ack_limit == INT_MAX) goto send_ack; /* Then check host-wide RFC 5961 rate limit. */ now = jiffies / HZ; if (now != READ_ONCE(net->ipv4.tcp_challenge_timestamp)) { u32 half = (ack_limit + 1) >> 1; WRITE_ONCE(net->ipv4.tcp_challenge_timestamp, now); WRITE_ONCE(net->ipv4.tcp_challenge_count, get_random_u32_inclusive(half, ack_limit + half - 1)); } count = READ_ONCE(net->ipv4.tcp_challenge_count); if (count > 0) { WRITE_ONCE(net->ipv4.tcp_challenge_count, count - 1); send_ack: NET_INC_STATS(net, LINUX_MIB_TCPCHALLENGEACK); tcp_send_ack(sk); } } static void tcp_store_ts_recent(struct tcp_sock *tp) { tp->rx_opt.ts_recent = tp->rx_opt.rcv_tsval; tp->rx_opt.ts_recent_stamp = ktime_get_seconds(); } static void tcp_replace_ts_recent(struct tcp_sock *tp, u32 seq) { if (tp->rx_opt.saw_tstamp && !after(seq, tp->rcv_wup)) { /* PAWS bug workaround wrt. ACK frames, the PAWS discard * extra check below makes sure this can only happen * for pure ACK frames. -DaveM * * Not only, also it occurs for expired timestamps. */ if (tcp_paws_check(&tp->rx_opt, 0)) tcp_store_ts_recent(tp); } } /* This routine deals with acks during a TLP episode and ends an episode by * resetting tlp_high_seq. Ref: TLP algorithm in draft-ietf-tcpm-rack */ static void tcp_process_tlp_ack(struct sock *sk, u32 ack, int flag) { struct tcp_sock *tp = tcp_sk(sk); if (before(ack, tp->tlp_high_seq)) return; if (!tp->tlp_retrans) { /* TLP of new data has been acknowledged */ tp->tlp_high_seq = 0; } else if (flag & FLAG_DSACK_TLP) { /* This DSACK means original and TLP probe arrived; no loss */ tp->tlp_high_seq = 0; } else if (after(ack, tp->tlp_high_seq)) { /* ACK advances: there was a loss, so reduce cwnd. Reset * tlp_high_seq in tcp_init_cwnd_reduction() */ tcp_init_cwnd_reduction(sk); tcp_set_ca_state(sk, TCP_CA_CWR); tcp_end_cwnd_reduction(sk); tcp_try_keep_open(sk); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPLOSSPROBERECOVERY); } else if (!(flag & (FLAG_SND_UNA_ADVANCED | FLAG_NOT_DUP | FLAG_DATA_SACKED))) { /* Pure dupack: original and TLP probe arrived; no loss */ tp->tlp_high_seq = 0; } } static inline void tcp_in_ack_event(struct sock *sk, u32 flags) { const struct inet_connection_sock *icsk = inet_csk(sk); if (icsk->icsk_ca_ops->in_ack_event) icsk->icsk_ca_ops->in_ack_event(sk, flags); } /* Congestion control has updated the cwnd already. So if we're in * loss recovery then now we do any new sends (for FRTO) or * retransmits (for CA_Loss or CA_recovery) that make sense. */ static void tcp_xmit_recovery(struct sock *sk, int rexmit) { struct tcp_sock *tp = tcp_sk(sk); if (rexmit == REXMIT_NONE || sk->sk_state == TCP_SYN_SENT) return; if (unlikely(rexmit == REXMIT_NEW)) { __tcp_push_pending_frames(sk, tcp_current_mss(sk), TCP_NAGLE_OFF); if (after(tp->snd_nxt, tp->high_seq)) return; tp->frto = 0; } tcp_xmit_retransmit_queue(sk); } /* Returns the number of packets newly acked or sacked by the current ACK */ static u32 tcp_newly_delivered(struct sock *sk, u32 prior_delivered, int flag) { const struct net *net = sock_net(sk); struct tcp_sock *tp = tcp_sk(sk); u32 delivered; delivered = tp->delivered - prior_delivered; NET_ADD_STATS(net, LINUX_MIB_TCPDELIVERED, delivered); if (flag & FLAG_ECE) NET_ADD_STATS(net, LINUX_MIB_TCPDELIVEREDCE, delivered); return delivered; } /* This routine deals with incoming acks, but not outgoing ones. */ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct tcp_sacktag_state sack_state; struct rate_sample rs = { .prior_delivered = 0 }; u32 prior_snd_una = tp->snd_una; bool is_sack_reneg = tp->is_sack_reneg; u32 ack_seq = TCP_SKB_CB(skb)->seq; u32 ack = TCP_SKB_CB(skb)->ack_seq; int num_dupack = 0; int prior_packets = tp->packets_out; u32 delivered = tp->delivered; u32 lost = tp->lost; int rexmit = REXMIT_NONE; /* Flag to (re)transmit to recover losses */ u32 prior_fack; sack_state.first_sackt = 0; sack_state.rate = &rs; sack_state.sack_delivered = 0; /* We very likely will need to access rtx queue. */ prefetch(sk->tcp_rtx_queue.rb_node); /* If the ack is older than previous acks * then we can probably ignore it. */ if (before(ack, prior_snd_una)) { /* RFC 5961 5.2 [Blind Data Injection Attack].[Mitigation] */ if (before(ack, prior_snd_una - tp->max_window)) { if (!(flag & FLAG_NO_CHALLENGE_ACK)) tcp_send_challenge_ack(sk); return -SKB_DROP_REASON_TCP_TOO_OLD_ACK; } goto old_ack; } /* If the ack includes data we haven't sent yet, discard * this segment (RFC793 Section 3.9). */ if (after(ack, tp->snd_nxt)) return -SKB_DROP_REASON_TCP_ACK_UNSENT_DATA; if (after(ack, prior_snd_una)) { flag |= FLAG_SND_UNA_ADVANCED; icsk->icsk_retransmits = 0; #if IS_ENABLED(CONFIG_TLS_DEVICE) if (static_branch_unlikely(&clean_acked_data_enabled.key)) if (icsk->icsk_clean_acked) icsk->icsk_clean_acked(sk, ack); #endif } prior_fack = tcp_is_sack(tp) ? tcp_highest_sack_seq(tp) : tp->snd_una; rs.prior_in_flight = tcp_packets_in_flight(tp); /* ts_recent update must be made after we are sure that the packet * is in window. */ if (flag & FLAG_UPDATE_TS_RECENT) tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq); if ((flag & (FLAG_SLOWPATH | FLAG_SND_UNA_ADVANCED)) == FLAG_SND_UNA_ADVANCED) { /* Window is constant, pure forward advance. * No more checks are required. * Note, we use the fact that SND.UNA>=SND.WL2. */ tcp_update_wl(tp, ack_seq); tcp_snd_una_update(tp, ack); flag |= FLAG_WIN_UPDATE; tcp_in_ack_event(sk, CA_ACK_WIN_UPDATE); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHPACKS); } else { u32 ack_ev_flags = CA_ACK_SLOWPATH; if (ack_seq != TCP_SKB_CB(skb)->end_seq) flag |= FLAG_DATA; else NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPUREACKS); flag |= tcp_ack_update_window(sk, skb, ack, ack_seq); if (TCP_SKB_CB(skb)->sacked) flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una, &sack_state); if (tcp_ecn_rcv_ecn_echo(tp, tcp_hdr(skb))) { flag |= FLAG_ECE; ack_ev_flags |= CA_ACK_ECE; } if (sack_state.sack_delivered) tcp_count_delivered(tp, sack_state.sack_delivered, flag & FLAG_ECE); if (flag & FLAG_WIN_UPDATE) ack_ev_flags |= CA_ACK_WIN_UPDATE; tcp_in_ack_event(sk, ack_ev_flags); } /* This is a deviation from RFC3168 since it states that: * "When the TCP data sender is ready to set the CWR bit after reducing * the congestion window, it SHOULD set the CWR bit only on the first * new data packet that it transmits." * We accept CWR on pure ACKs to be more robust * with widely-deployed TCP implementations that do this. */ tcp_ecn_accept_cwr(sk, skb); /* We passed data and got it acked, remove any soft error * log. Something worked... */ WRITE_ONCE(sk->sk_err_soft, 0); icsk->icsk_probes_out = 0; tp->rcv_tstamp = tcp_jiffies32; if (!prior_packets) goto no_queue; /* See if we can take anything off of the retransmit queue. */ flag |= tcp_clean_rtx_queue(sk, skb, prior_fack, prior_snd_una, &sack_state, flag & FLAG_ECE); tcp_rack_update_reo_wnd(sk, &rs); if (tp->tlp_high_seq) tcp_process_tlp_ack(sk, ack, flag); if (tcp_ack_is_dubious(sk, flag)) { if (!(flag & (FLAG_SND_UNA_ADVANCED | FLAG_NOT_DUP | FLAG_DSACKING_ACK))) { num_dupack = 1; /* Consider if pure acks were aggregated in tcp_add_backlog() */ if (!(flag & FLAG_DATA)) num_dupack = max_t(u16, 1, skb_shinfo(skb)->gso_segs); } tcp_fastretrans_alert(sk, prior_snd_una, num_dupack, &flag, &rexmit); } /* If needed, reset TLP/RTO timer when RACK doesn't set. */ if (flag & FLAG_SET_XMIT_TIMER) tcp_set_xmit_timer(sk); if ((flag & FLAG_FORWARD_PROGRESS) || !(flag & FLAG_NOT_DUP)) sk_dst_confirm(sk); delivered = tcp_newly_delivered(sk, delivered, flag); lost = tp->lost - lost; /* freshly marked lost */ rs.is_ack_delayed = !!(flag & FLAG_ACK_MAYBE_DELAYED); tcp_rate_gen(sk, delivered, lost, is_sack_reneg, sack_state.rate); tcp_cong_control(sk, ack, delivered, flag, sack_state.rate); tcp_xmit_recovery(sk, rexmit); return 1; no_queue: /* If data was DSACKed, see if we can undo a cwnd reduction. */ if (flag & FLAG_DSACKING_ACK) { tcp_fastretrans_alert(sk, prior_snd_una, num_dupack, &flag, &rexmit); tcp_newly_delivered(sk, delivered, flag); } /* If this ack opens up a zero window, clear backoff. It was * being used to time the probes, and is probably far higher than * it needs to be for normal retransmission. */ tcp_ack_probe(sk); if (tp->tlp_high_seq) tcp_process_tlp_ack(sk, ack, flag); return 1; old_ack: /* If data was SACKed, tag it and see if we should send more data. * If data was DSACKed, see if we can undo a cwnd reduction. */ if (TCP_SKB_CB(skb)->sacked) { flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una, &sack_state); tcp_fastretrans_alert(sk, prior_snd_una, num_dupack, &flag, &rexmit); tcp_newly_delivered(sk, delivered, flag); tcp_xmit_recovery(sk, rexmit); } return 0; } static void tcp_parse_fastopen_option(int len, const unsigned char *cookie, bool syn, struct tcp_fastopen_cookie *foc, bool exp_opt) { /* Valid only in SYN or SYN-ACK with an even length. */ if (!foc || !syn || len < 0 || (len & 1)) return; if (len >= TCP_FASTOPEN_COOKIE_MIN && len <= TCP_FASTOPEN_COOKIE_MAX) memcpy(foc->val, cookie, len); else if (len != 0) len = -1; foc->len = len; foc->exp = exp_opt; } static bool smc_parse_options(const struct tcphdr *th, struct tcp_options_received *opt_rx, const unsigned char *ptr, int opsize) { #if IS_ENABLED(CONFIG_SMC) if (static_branch_unlikely(&tcp_have_smc)) { if (th->syn && !(opsize & 1) && opsize >= TCPOLEN_EXP_SMC_BASE && get_unaligned_be32(ptr) == TCPOPT_SMC_MAGIC) { opt_rx->smc_ok = 1; return true; } } #endif return false; } /* Try to parse the MSS option from the TCP header. Return 0 on failure, clamped * value on success. */ u16 tcp_parse_mss_option(const struct tcphdr *th, u16 user_mss) { const unsigned char *ptr = (const unsigned char *)(th + 1); int length = (th->doff * 4) - sizeof(struct tcphdr); u16 mss = 0; while (length > 0) { int opcode = *ptr++; int opsize; switch (opcode) { case TCPOPT_EOL: return mss; case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */ length--; continue; default: if (length < 2) return mss; opsize = *ptr++; if (opsize < 2) /* "silly options" */ return mss; if (opsize > length) return mss; /* fail on partial options */ if (opcode == TCPOPT_MSS && opsize == TCPOLEN_MSS) { u16 in_mss = get_unaligned_be16(ptr); if (in_mss) { if (user_mss && user_mss < in_mss) in_mss = user_mss; mss = in_mss; } } ptr += opsize - 2; length -= opsize; } } return mss; } EXPORT_SYMBOL_GPL(tcp_parse_mss_option); /* Look for tcp options. Normally only called on SYN and SYNACK packets. * But, this can also be called on packets in the established flow when * the fast version below fails. */ void tcp_parse_options(const struct net *net, const struct sk_buff *skb, struct tcp_options_received *opt_rx, int estab, struct tcp_fastopen_cookie *foc) { const unsigned char *ptr; const struct tcphdr *th = tcp_hdr(skb); int length = (th->doff * 4) - sizeof(struct tcphdr); ptr = (const unsigned char *)(th + 1); opt_rx->saw_tstamp = 0; opt_rx->saw_unknown = 0; while (length > 0) { int opcode = *ptr++; int opsize; switch (opcode) { case TCPOPT_EOL: return; case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */ length--; continue; default: if (length < 2) return; opsize = *ptr++; if (opsize < 2) /* "silly options" */ return; if (opsize > length) return; /* don't parse partial options */ switch (opcode) { case TCPOPT_MSS: if (opsize == TCPOLEN_MSS && th->syn && !estab) { u16 in_mss = get_unaligned_be16(ptr); if (in_mss) { if (opt_rx->user_mss && opt_rx->user_mss < in_mss) in_mss = opt_rx->user_mss; opt_rx->mss_clamp = in_mss; } } break; case TCPOPT_WINDOW: if (opsize == TCPOLEN_WINDOW && th->syn && !estab && READ_ONCE(net->ipv4.sysctl_tcp_window_scaling)) { __u8 snd_wscale = *(__u8 *)ptr; opt_rx->wscale_ok = 1; if (snd_wscale > TCP_MAX_WSCALE) { net_info_ratelimited("%s: Illegal window scaling value %d > %u received\n", __func__, snd_wscale, TCP_MAX_WSCALE); snd_wscale = TCP_MAX_WSCALE; } opt_rx->snd_wscale = snd_wscale; } break; case TCPOPT_TIMESTAMP: if ((opsize == TCPOLEN_TIMESTAMP) && ((estab && opt_rx->tstamp_ok) || (!estab && READ_ONCE(net->ipv4.sysctl_tcp_timestamps)))) { opt_rx->saw_tstamp = 1; opt_rx->rcv_tsval = get_unaligned_be32(ptr); opt_rx->rcv_tsecr = get_unaligned_be32(ptr + 4); } break; case TCPOPT_SACK_PERM: if (opsize == TCPOLEN_SACK_PERM && th->syn && !estab && READ_ONCE(net->ipv4.sysctl_tcp_sack)) { opt_rx->sack_ok = TCP_SACK_SEEN; tcp_sack_reset(opt_rx); } break; case TCPOPT_SACK: if ((opsize >= (TCPOLEN_SACK_BASE + TCPOLEN_SACK_PERBLOCK)) && !((opsize - TCPOLEN_SACK_BASE) % TCPOLEN_SACK_PERBLOCK) && opt_rx->sack_ok) { TCP_SKB_CB(skb)->sacked = (ptr - 2) - (unsigned char *)th; } break; #ifdef CONFIG_TCP_MD5SIG case TCPOPT_MD5SIG: /* The MD5 Hash has already been * checked (see tcp_v{4,6}_rcv()). */ break; #endif case TCPOPT_FASTOPEN: tcp_parse_fastopen_option( opsize - TCPOLEN_FASTOPEN_BASE, ptr, th->syn, foc, false); break; case TCPOPT_EXP: /* Fast Open option shares code 254 using a * 16 bits magic number. */ if (opsize >= TCPOLEN_EXP_FASTOPEN_BASE && get_unaligned_be16(ptr) == TCPOPT_FASTOPEN_MAGIC) { tcp_parse_fastopen_option(opsize - TCPOLEN_EXP_FASTOPEN_BASE, ptr + 2, th->syn, foc, true); break; } if (smc_parse_options(th, opt_rx, ptr, opsize)) break; opt_rx->saw_unknown = 1; break; default: opt_rx->saw_unknown = 1; } ptr += opsize-2; length -= opsize; } } } EXPORT_SYMBOL(tcp_parse_options); static bool tcp_parse_aligned_timestamp(struct tcp_sock *tp, const struct tcphdr *th) { const __be32 *ptr = (const __be32 *)(th + 1); if (*ptr == htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP)) { tp->rx_opt.saw_tstamp = 1; ++ptr; tp->rx_opt.rcv_tsval = ntohl(*ptr); ++ptr; if (*ptr) tp->rx_opt.rcv_tsecr = ntohl(*ptr) - tp->tsoffset; else tp->rx_opt.rcv_tsecr = 0; return true; } return false; } /* Fast parse options. This hopes to only see timestamps. * If it is wrong it falls back on tcp_parse_options(). */ static bool tcp_fast_parse_options(const struct net *net, const struct sk_buff *skb, const struct tcphdr *th, struct tcp_sock *tp) { /* In the spirit of fast parsing, compare doff directly to constant * values. Because equality is used, short doff can be ignored here. */ if (th->doff == (sizeof(*th) / 4)) { tp->rx_opt.saw_tstamp = 0; return false; } else if (tp->rx_opt.tstamp_ok && th->doff == ((sizeof(*th) + TCPOLEN_TSTAMP_ALIGNED) / 4)) { if (tcp_parse_aligned_timestamp(tp, th)) return true; } tcp_parse_options(net, skb, &tp->rx_opt, 1, NULL); if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr) tp->rx_opt.rcv_tsecr -= tp->tsoffset; return true; } #ifdef CONFIG_TCP_MD5SIG /* * Parse MD5 Signature option */ const u8 *tcp_parse_md5sig_option(const struct tcphdr *th) { int length = (th->doff << 2) - sizeof(*th); const u8 *ptr = (const u8 *)(th + 1); /* If not enough data remaining, we can short cut */ while (length >= TCPOLEN_MD5SIG) { int opcode = *ptr++; int opsize; switch (opcode) { case TCPOPT_EOL: return NULL; case TCPOPT_NOP: length--; continue; default: opsize = *ptr++; if (opsize < 2 || opsize > length) return NULL; if (opcode == TCPOPT_MD5SIG) return opsize == TCPOLEN_MD5SIG ? ptr : NULL; } ptr += opsize - 2; length -= opsize; } return NULL; } EXPORT_SYMBOL(tcp_parse_md5sig_option); #endif /* Sorry, PAWS as specified is broken wrt. pure-ACKs -DaveM * * It is not fatal. If this ACK does _not_ change critical state (seqs, window) * it can pass through stack. So, the following predicate verifies that * this segment is not used for anything but congestion avoidance or * fast retransmit. Moreover, we even are able to eliminate most of such * second order effects, if we apply some small "replay" window (~RTO) * to timestamp space. * * All these measures still do not guarantee that we reject wrapped ACKs * on networks with high bandwidth, when sequence space is recycled fastly, * but it guarantees that such events will be very rare and do not affect * connection seriously. This doesn't look nice, but alas, PAWS is really * buggy extension. * * [ Later note. Even worse! It is buggy for segments _with_ data. RFC * states that events when retransmit arrives after original data are rare. * It is a blatant lie. VJ forgot about fast retransmit! 8)8) It is * the biggest problem on large power networks even with minor reordering. * OK, let's give it small replay window. If peer clock is even 1hz, it is safe * up to bandwidth of 18Gigabit/sec. 8) ] */ static int tcp_disordered_ack(const struct sock *sk, const struct sk_buff *skb) { const struct tcp_sock *tp = tcp_sk(sk); const struct tcphdr *th = tcp_hdr(skb); u32 seq = TCP_SKB_CB(skb)->seq; u32 ack = TCP_SKB_CB(skb)->ack_seq; return (/* 1. Pure ACK with correct sequence number. */ (th->ack && seq == TCP_SKB_CB(skb)->end_seq && seq == tp->rcv_nxt) && /* 2. ... and duplicate ACK. */ ack == tp->snd_una && /* 3. ... and does not update window. */ !tcp_may_update_window(tp, ack, seq, ntohs(th->window) << tp->rx_opt.snd_wscale) && /* 4. ... and sits in replay window. */ (s32)(tp->rx_opt.ts_recent - tp->rx_opt.rcv_tsval) <= (inet_csk(sk)->icsk_rto * 1024) / HZ); } static inline bool tcp_paws_discard(const struct sock *sk, const struct sk_buff *skb) { const struct tcp_sock *tp = tcp_sk(sk); return !tcp_paws_check(&tp->rx_opt, TCP_PAWS_WINDOW) && !tcp_disordered_ack(sk, skb); } /* Check segment sequence number for validity. * * Segment controls are considered valid, if the segment * fits to the window after truncation to the window. Acceptability * of data (and SYN, FIN, of course) is checked separately. * See tcp_data_queue(), for example. * * Also, controls (RST is main one) are accepted using RCV.WUP instead * of RCV.NXT. Peer still did not advance his SND.UNA when we * delayed ACK, so that hisSND.UNA<=ourRCV.WUP. * (borrowed from freebsd) */ static enum skb_drop_reason tcp_sequence(const struct tcp_sock *tp, u32 seq, u32 end_seq) { if (before(end_seq, tp->rcv_wup)) return SKB_DROP_REASON_TCP_OLD_SEQUENCE; if (after(seq, tp->rcv_nxt + tcp_receive_window(tp))) return SKB_DROP_REASON_TCP_INVALID_SEQUENCE; return SKB_NOT_DROPPED_YET; } /* When we get a reset we do this. */ void tcp_reset(struct sock *sk, struct sk_buff *skb) { trace_tcp_receive_reset(sk); /* mptcp can't tell us to ignore reset pkts, * so just ignore the return value of mptcp_incoming_options(). */ if (sk_is_mptcp(sk)) mptcp_incoming_options(sk, skb); /* We want the right error as BSD sees it (and indeed as we do). */ switch (sk->sk_state) { case TCP_SYN_SENT: WRITE_ONCE(sk->sk_err, ECONNREFUSED); break; case TCP_CLOSE_WAIT: WRITE_ONCE(sk->sk_err, EPIPE); break; case TCP_CLOSE: return; default: WRITE_ONCE(sk->sk_err, ECONNRESET); } /* This barrier is coupled with smp_rmb() in tcp_poll() */ smp_wmb(); tcp_write_queue_purge(sk); tcp_done(sk); if (!sock_flag(sk, SOCK_DEAD)) sk_error_report(sk); } /* * Process the FIN bit. This now behaves as it is supposed to work * and the FIN takes effect when it is validly part of sequence * space. Not before when we get holes. * * If we are ESTABLISHED, a received fin moves us to CLOSE-WAIT * (and thence onto LAST-ACK and finally, CLOSE, we never enter * TIME-WAIT) * * If we are in FINWAIT-1, a received FIN indicates simultaneous * close and we go into CLOSING (and later onto TIME-WAIT) * * If we are in FINWAIT-2, a received FIN moves us to TIME-WAIT. */ void tcp_fin(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); inet_csk_schedule_ack(sk); WRITE_ONCE(sk->sk_shutdown, sk->sk_shutdown | RCV_SHUTDOWN); sock_set_flag(sk, SOCK_DONE); switch (sk->sk_state) { case TCP_SYN_RECV: case TCP_ESTABLISHED: /* Move to CLOSE_WAIT */ tcp_set_state(sk, TCP_CLOSE_WAIT); inet_csk_enter_pingpong_mode(sk); break; case TCP_CLOSE_WAIT: case TCP_CLOSING: /* Received a retransmission of the FIN, do * nothing. */ break; case TCP_LAST_ACK: /* RFC793: Remain in the LAST-ACK state. */ break; case TCP_FIN_WAIT1: /* This case occurs when a simultaneous close * happens, we must ack the received FIN and * enter the CLOSING state. */ tcp_send_ack(sk); tcp_set_state(sk, TCP_CLOSING); break; case TCP_FIN_WAIT2: /* Received a FIN -- send ACK and enter TIME_WAIT. */ tcp_send_ack(sk); tcp_time_wait(sk, TCP_TIME_WAIT, 0); break; default: /* Only TCP_LISTEN and TCP_CLOSE are left, in these * cases we should never reach this piece of code. */ pr_err("%s: Impossible, sk->sk_state=%d\n", __func__, sk->sk_state); break; } /* It _is_ possible, that we have something out-of-order _after_ FIN. * Probably, we should reset in this case. For now drop them. */ skb_rbtree_purge(&tp->out_of_order_queue); if (tcp_is_sack(tp)) tcp_sack_reset(&tp->rx_opt); if (!sock_flag(sk, SOCK_DEAD)) { sk->sk_state_change(sk); /* Do not send POLL_HUP for half duplex close. */ if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == TCP_CLOSE) sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP); else sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); } } static inline bool tcp_sack_extend(struct tcp_sack_block *sp, u32 seq, u32 end_seq) { if (!after(seq, sp->end_seq) && !after(sp->start_seq, end_seq)) { if (before(seq, sp->start_seq)) sp->start_seq = seq; if (after(end_seq, sp->end_seq)) sp->end_seq = end_seq; return true; } return false; } static void tcp_dsack_set(struct sock *sk, u32 seq, u32 end_seq) { struct tcp_sock *tp = tcp_sk(sk); if (tcp_is_sack(tp) && READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_dsack)) { int mib_idx; if (before(seq, tp->rcv_nxt)) mib_idx = LINUX_MIB_TCPDSACKOLDSENT; else mib_idx = LINUX_MIB_TCPDSACKOFOSENT; NET_INC_STATS(sock_net(sk), mib_idx); tp->rx_opt.dsack = 1; tp->duplicate_sack[0].start_seq = seq; tp->duplicate_sack[0].end_seq = end_seq; } } static void tcp_dsack_extend(struct sock *sk, u32 seq, u32 end_seq) { struct tcp_sock *tp = tcp_sk(sk); if (!tp->rx_opt.dsack) tcp_dsack_set(sk, seq, end_seq); else tcp_sack_extend(tp->duplicate_sack, seq, end_seq); } static void tcp_rcv_spurious_retrans(struct sock *sk, const struct sk_buff *skb) { /* When the ACK path fails or drops most ACKs, the sender would * timeout and spuriously retransmit the same segment repeatedly. * The receiver remembers and reflects via DSACKs. Leverage the * DSACK state and change the txhash to re-route speculatively. */ if (TCP_SKB_CB(skb)->seq == tcp_sk(sk)->duplicate_sack[0].start_seq && sk_rethink_txhash(sk)) NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDUPLICATEDATAREHASH); } static void tcp_send_dupack(struct sock *sk, const struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq && before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOST); tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); if (tcp_is_sack(tp) && READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_dsack)) { u32 end_seq = TCP_SKB_CB(skb)->end_seq; tcp_rcv_spurious_retrans(sk, skb); if (after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt)) end_seq = tp->rcv_nxt; tcp_dsack_set(sk, TCP_SKB_CB(skb)->seq, end_seq); } } tcp_send_ack(sk); } /* These routines update the SACK block as out-of-order packets arrive or * in-order packets close up the sequence space. */ static void tcp_sack_maybe_coalesce(struct tcp_sock *tp) { int this_sack; struct tcp_sack_block *sp = &tp->selective_acks[0]; struct tcp_sack_block *swalk = sp + 1; /* See if the recent change to the first SACK eats into * or hits the sequence space of other SACK blocks, if so coalesce. */ for (this_sack = 1; this_sack < tp->rx_opt.num_sacks;) { if (tcp_sack_extend(sp, swalk->start_seq, swalk->end_seq)) { int i; /* Zap SWALK, by moving every further SACK up by one slot. * Decrease num_sacks. */ tp->rx_opt.num_sacks--; for (i = this_sack; i < tp->rx_opt.num_sacks; i++) sp[i] = sp[i + 1]; continue; } this_sack++; swalk++; } } void tcp_sack_compress_send_ack(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); if (!tp->compressed_ack) return; if (hrtimer_try_to_cancel(&tp->compressed_ack_timer) == 1) __sock_put(sk); /* Since we have to send one ack finally, * substract one from tp->compressed_ack to keep * LINUX_MIB_TCPACKCOMPRESSED accurate. */ NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPACKCOMPRESSED, tp->compressed_ack - 1); tp->compressed_ack = 0; tcp_send_ack(sk); } /* Reasonable amount of sack blocks included in TCP SACK option * The max is 4, but this becomes 3 if TCP timestamps are there. * Given that SACK packets might be lost, be conservative and use 2. */ #define TCP_SACK_BLOCKS_EXPECTED 2 static void tcp_sack_new_ofo_skb(struct sock *sk, u32 seq, u32 end_seq) { struct tcp_sock *tp = tcp_sk(sk); struct tcp_sack_block *sp = &tp->selective_acks[0]; int cur_sacks = tp->rx_opt.num_sacks; int this_sack; if (!cur_sacks) goto new_sack; for (this_sack = 0; this_sack < cur_sacks; this_sack++, sp++) { if (tcp_sack_extend(sp, seq, end_seq)) { if (this_sack >= TCP_SACK_BLOCKS_EXPECTED) tcp_sack_compress_send_ack(sk); /* Rotate this_sack to the first one. */ for (; this_sack > 0; this_sack--, sp--) swap(*sp, *(sp - 1)); if (cur_sacks > 1) tcp_sack_maybe_coalesce(tp); return; } } if (this_sack >= TCP_SACK_BLOCKS_EXPECTED) tcp_sack_compress_send_ack(sk); /* Could not find an adjacent existing SACK, build a new one, * put it at the front, and shift everyone else down. We * always know there is at least one SACK present already here. * * If the sack array is full, forget about the last one. */ if (this_sack >= TCP_NUM_SACKS) { this_sack--; tp->rx_opt.num_sacks--; sp--; } for (; this_sack > 0; this_sack--, sp--) *sp = *(sp - 1); new_sack: /* Build the new head SACK, and we're done. */ sp->start_seq = seq; sp->end_seq = end_seq; tp->rx_opt.num_sacks++; } /* RCV.NXT advances, some SACKs should be eaten. */ static void tcp_sack_remove(struct tcp_sock *tp) { struct tcp_sack_block *sp = &tp->selective_acks[0]; int num_sacks = tp->rx_opt.num_sacks; int this_sack; /* Empty ofo queue, hence, all the SACKs are eaten. Clear. */ if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) { tp->rx_opt.num_sacks = 0; return; } for (this_sack = 0; this_sack < num_sacks;) { /* Check if the start of the sack is covered by RCV.NXT. */ if (!before(tp->rcv_nxt, sp->start_seq)) { int i; /* RCV.NXT must cover all the block! */ WARN_ON(before(tp->rcv_nxt, sp->end_seq)); /* Zap this SACK, by moving forward any other SACKS. */ for (i = this_sack+1; i < num_sacks; i++) tp->selective_acks[i-1] = tp->selective_acks[i]; num_sacks--; continue; } this_sack++; sp++; } tp->rx_opt.num_sacks = num_sacks; } /** * tcp_try_coalesce - try to merge skb to prior one * @sk: socket * @to: prior buffer * @from: buffer to add in queue * @fragstolen: pointer to boolean * * Before queueing skb @from after @to, try to merge them * to reduce overall memory use and queue lengths, if cost is small. * Packets in ofo or receive queues can stay a long time. * Better try to coalesce them right now to avoid future collapses. * Returns true if caller should free @from instead of queueing it */ static bool tcp_try_coalesce(struct sock *sk, struct sk_buff *to, struct sk_buff *from, bool *fragstolen) { int delta; *fragstolen = false; /* Its possible this segment overlaps with prior segment in queue */ if (TCP_SKB_CB(from)->seq != TCP_SKB_CB(to)->end_seq) return false; if (!mptcp_skb_can_collapse(to, from)) return false; #ifdef CONFIG_TLS_DEVICE if (from->decrypted != to->decrypted) return false; #endif if (!skb_try_coalesce(to, from, fragstolen, &delta)) return false; atomic_add(delta, &sk->sk_rmem_alloc); sk_mem_charge(sk, delta); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOALESCE); TCP_SKB_CB(to)->end_seq = TCP_SKB_CB(from)->end_seq; TCP_SKB_CB(to)->ack_seq = TCP_SKB_CB(from)->ack_seq; TCP_SKB_CB(to)->tcp_flags |= TCP_SKB_CB(from)->tcp_flags; if (TCP_SKB_CB(from)->has_rxtstamp) { TCP_SKB_CB(to)->has_rxtstamp = true; to->tstamp = from->tstamp; skb_hwtstamps(to)->hwtstamp = skb_hwtstamps(from)->hwtstamp; } return true; } static bool tcp_ooo_try_coalesce(struct sock *sk, struct sk_buff *to, struct sk_buff *from, bool *fragstolen) { bool res = tcp_try_coalesce(sk, to, from, fragstolen); /* In case tcp_drop_reason() is called later, update to->gso_segs */ if (res) { u32 gso_segs = max_t(u16, 1, skb_shinfo(to)->gso_segs) + max_t(u16, 1, skb_shinfo(from)->gso_segs); skb_shinfo(to)->gso_segs = min_t(u32, gso_segs, 0xFFFF); } return res; } static void tcp_drop_reason(struct sock *sk, struct sk_buff *skb, enum skb_drop_reason reason) { sk_drops_add(sk, skb); kfree_skb_reason(skb, reason); } /* This one checks to see if we can put data from the * out_of_order queue into the receive_queue. */ static void tcp_ofo_queue(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); __u32 dsack_high = tp->rcv_nxt; bool fin, fragstolen, eaten; struct sk_buff *skb, *tail; struct rb_node *p; p = rb_first(&tp->out_of_order_queue); while (p) { skb = rb_to_skb(p); if (after(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) break; if (before(TCP_SKB_CB(skb)->seq, dsack_high)) { __u32 dsack = dsack_high; if (before(TCP_SKB_CB(skb)->end_seq, dsack_high)) dsack_high = TCP_SKB_CB(skb)->end_seq; tcp_dsack_extend(sk, TCP_SKB_CB(skb)->seq, dsack); } p = rb_next(p); rb_erase(&skb->rbnode, &tp->out_of_order_queue); if (unlikely(!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt))) { tcp_drop_reason(sk, skb, SKB_DROP_REASON_TCP_OFO_DROP); continue; } tail = skb_peek_tail(&sk->sk_receive_queue); eaten = tail && tcp_try_coalesce(sk, tail, skb, &fragstolen); tcp_rcv_nxt_update(tp, TCP_SKB_CB(skb)->end_seq); fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN; if (!eaten) __skb_queue_tail(&sk->sk_receive_queue, skb); else kfree_skb_partial(skb, fragstolen); if (unlikely(fin)) { tcp_fin(sk); /* tcp_fin() purges tp->out_of_order_queue, * so we must end this loop right now. */ break; } } } static bool tcp_prune_ofo_queue(struct sock *sk, const struct sk_buff *in_skb); static int tcp_prune_queue(struct sock *sk, const struct sk_buff *in_skb); static int tcp_try_rmem_schedule(struct sock *sk, struct sk_buff *skb, unsigned int size) { if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || !sk_rmem_schedule(sk, skb, size)) { if (tcp_prune_queue(sk, skb) < 0) return -1; while (!sk_rmem_schedule(sk, skb, size)) { if (!tcp_prune_ofo_queue(sk, skb)) return -1; } } return 0; } static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); struct rb_node **p, *parent; struct sk_buff *skb1; u32 seq, end_seq; bool fragstolen; tcp_ecn_check_ce(sk, skb); if (unlikely(tcp_try_rmem_schedule(sk, skb, skb->truesize))) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFODROP); sk->sk_data_ready(sk); tcp_drop_reason(sk, skb, SKB_DROP_REASON_PROTO_MEM); return; } /* Disable header prediction. */ tp->pred_flags = 0; inet_csk_schedule_ack(sk); tp->rcv_ooopack += max_t(u16, 1, skb_shinfo(skb)->gso_segs); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOQUEUE); seq = TCP_SKB_CB(skb)->seq; end_seq = TCP_SKB_CB(skb)->end_seq; p = &tp->out_of_order_queue.rb_node; if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) { /* Initial out of order segment, build 1 SACK. */ if (tcp_is_sack(tp)) { tp->rx_opt.num_sacks = 1; tp->selective_acks[0].start_seq = seq; tp->selective_acks[0].end_seq = end_seq; } rb_link_node(&skb->rbnode, NULL, p); rb_insert_color(&skb->rbnode, &tp->out_of_order_queue); tp->ooo_last_skb = skb; goto end; } /* In the typical case, we are adding an skb to the end of the list. * Use of ooo_last_skb avoids the O(Log(N)) rbtree lookup. */ if (tcp_ooo_try_coalesce(sk, tp->ooo_last_skb, skb, &fragstolen)) { coalesce_done: /* For non sack flows, do not grow window to force DUPACK * and trigger fast retransmit. */ if (tcp_is_sack(tp)) tcp_grow_window(sk, skb, true); kfree_skb_partial(skb, fragstolen); skb = NULL; goto add_sack; } /* Can avoid an rbtree lookup if we are adding skb after ooo_last_skb */ if (!before(seq, TCP_SKB_CB(tp->ooo_last_skb)->end_seq)) { parent = &tp->ooo_last_skb->rbnode; p = &parent->rb_right; goto insert; } /* Find place to insert this segment. Handle overlaps on the way. */ parent = NULL; while (*p) { parent = *p; skb1 = rb_to_skb(parent); if (before(seq, TCP_SKB_CB(skb1)->seq)) { p = &parent->rb_left; continue; } if (before(seq, TCP_SKB_CB(skb1)->end_seq)) { if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq)) { /* All the bits are present. Drop. */ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE); tcp_drop_reason(sk, skb, SKB_DROP_REASON_TCP_OFOMERGE); skb = NULL; tcp_dsack_set(sk, seq, end_seq); goto add_sack; } if (after(seq, TCP_SKB_CB(skb1)->seq)) { /* Partial overlap. */ tcp_dsack_set(sk, seq, TCP_SKB_CB(skb1)->end_seq); } else { /* skb's seq == skb1's seq and skb covers skb1. * Replace skb1 with skb. */ rb_replace_node(&skb1->rbnode, &skb->rbnode, &tp->out_of_order_queue); tcp_dsack_extend(sk, TCP_SKB_CB(skb1)->seq, TCP_SKB_CB(skb1)->end_seq); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE); tcp_drop_reason(sk, skb1, SKB_DROP_REASON_TCP_OFOMERGE); goto merge_right; } } else if (tcp_ooo_try_coalesce(sk, skb1, skb, &fragstolen)) { goto coalesce_done; } p = &parent->rb_right; } insert: /* Insert segment into RB tree. */ rb_link_node(&skb->rbnode, parent, p); rb_insert_color(&skb->rbnode, &tp->out_of_order_queue); merge_right: /* Remove other segments covered by skb. */ while ((skb1 = skb_rb_next(skb)) != NULL) { if (!after(end_seq, TCP_SKB_CB(skb1)->seq)) break; if (before(end_seq, TCP_SKB_CB(skb1)->end_seq)) { tcp_dsack_extend(sk, TCP_SKB_CB(skb1)->seq, end_seq); break; } rb_erase(&skb1->rbnode, &tp->out_of_order_queue); tcp_dsack_extend(sk, TCP_SKB_CB(skb1)->seq, TCP_SKB_CB(skb1)->end_seq); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE); tcp_drop_reason(sk, skb1, SKB_DROP_REASON_TCP_OFOMERGE); } /* If there is no skb after us, we are the last_skb ! */ if (!skb1) tp->ooo_last_skb = skb; add_sack: if (tcp_is_sack(tp)) tcp_sack_new_ofo_skb(sk, seq, end_seq); end: if (skb) { /* For non sack flows, do not grow window to force DUPACK * and trigger fast retransmit. */ if (tcp_is_sack(tp)) tcp_grow_window(sk, skb, false); skb_condense(skb); skb_set_owner_r(skb, sk); } } static int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb, bool *fragstolen) { int eaten; struct sk_buff *tail = skb_peek_tail(&sk->sk_receive_queue); eaten = (tail && tcp_try_coalesce(sk, tail, skb, fragstolen)) ? 1 : 0; tcp_rcv_nxt_update(tcp_sk(sk), TCP_SKB_CB(skb)->end_seq); if (!eaten) { __skb_queue_tail(&sk->sk_receive_queue, skb); skb_set_owner_r(skb, sk); } return eaten; } int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size) { struct sk_buff *skb; int err = -ENOMEM; int data_len = 0; bool fragstolen; if (size == 0) return 0; if (size > PAGE_SIZE) { int npages = min_t(size_t, size >> PAGE_SHIFT, MAX_SKB_FRAGS); data_len = npages << PAGE_SHIFT; size = data_len + (size & ~PAGE_MASK); } skb = alloc_skb_with_frags(size - data_len, data_len, PAGE_ALLOC_COSTLY_ORDER, &err, sk->sk_allocation); if (!skb) goto err; skb_put(skb, size - data_len); skb->data_len = data_len; skb->len = size; if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVQDROP); goto err_free; } err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size); if (err) goto err_free; TCP_SKB_CB(skb)->seq = tcp_sk(sk)->rcv_nxt; TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq + size; TCP_SKB_CB(skb)->ack_seq = tcp_sk(sk)->snd_una - 1; if (tcp_queue_rcv(sk, skb, &fragstolen)) { WARN_ON_ONCE(fragstolen); /* should not happen */ __kfree_skb(skb); } return size; err_free: kfree_skb(skb); err: return err; } void tcp_data_ready(struct sock *sk) { if (tcp_epollin_ready(sk, sk->sk_rcvlowat) || sock_flag(sk, SOCK_DONE)) sk->sk_data_ready(sk); } static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); enum skb_drop_reason reason; bool fragstolen; int eaten; /* If a subflow has been reset, the packet should not continue * to be processed, drop the packet. */ if (sk_is_mptcp(sk) && !mptcp_incoming_options(sk, skb)) { __kfree_skb(skb); return; } if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) { __kfree_skb(skb); return; } skb_dst_drop(skb); __skb_pull(skb, tcp_hdr(skb)->doff * 4); reason = SKB_DROP_REASON_NOT_SPECIFIED; tp->rx_opt.dsack = 0; /* Queue data for delivery to the user. * Packets in sequence go to the receive queue. * Out of sequence packets to the out_of_order_queue. */ if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt) { if (tcp_receive_window(tp) == 0) { reason = SKB_DROP_REASON_TCP_ZEROWINDOW; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP); goto out_of_window; } /* Ok. In sequence. In window. */ queue_and_out: if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) { /* TODO: maybe ratelimit these WIN 0 ACK ? */ inet_csk(sk)->icsk_ack.pending |= (ICSK_ACK_NOMEM | ICSK_ACK_NOW); inet_csk_schedule_ack(sk); sk->sk_data_ready(sk); if (skb_queue_len(&sk->sk_receive_queue)) { reason = SKB_DROP_REASON_PROTO_MEM; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVQDROP); goto drop; } sk_forced_mem_schedule(sk, skb->truesize); } eaten = tcp_queue_rcv(sk, skb, &fragstolen); if (skb->len) tcp_event_data_recv(sk, skb); if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) tcp_fin(sk); if (!RB_EMPTY_ROOT(&tp->out_of_order_queue)) { tcp_ofo_queue(sk); /* RFC5681. 4.2. SHOULD send immediate ACK, when * gap in queue is filled. */ if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW; } if (tp->rx_opt.num_sacks) tcp_sack_remove(tp); tcp_fast_path_check(sk); if (eaten > 0) kfree_skb_partial(skb, fragstolen); if (!sock_flag(sk, SOCK_DEAD)) tcp_data_ready(sk); return; } if (!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt)) { tcp_rcv_spurious_retrans(sk, skb); /* A retransmit, 2nd most common case. Force an immediate ack. */ reason = SKB_DROP_REASON_TCP_OLD_DATA; NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOST); tcp_dsack_set(sk, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq); out_of_window: tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); inet_csk_schedule_ack(sk); drop: tcp_drop_reason(sk, skb, reason); return; } /* Out of window. F.e. zero window probe. */ if (!before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt + tcp_receive_window(tp))) { reason = SKB_DROP_REASON_TCP_OVERWINDOW; goto out_of_window; } if (before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) { /* Partial packet, seq < rcv_next < end_seq */ tcp_dsack_set(sk, TCP_SKB_CB(skb)->seq, tp->rcv_nxt); /* If window is closed, drop tail of packet. But after * remembering D-SACK for its head made in previous line. */ if (!tcp_receive_window(tp)) { reason = SKB_DROP_REASON_TCP_ZEROWINDOW; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP); goto out_of_window; } goto queue_and_out; } tcp_data_queue_ofo(sk, skb); } static struct sk_buff *tcp_skb_next(struct sk_buff *skb, struct sk_buff_head *list) { if (list) return !skb_queue_is_last(list, skb) ? skb->next : NULL; return skb_rb_next(skb); } static struct sk_buff *tcp_collapse_one(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *list, struct rb_root *root) { struct sk_buff *next = tcp_skb_next(skb, list); if (list) __skb_unlink(skb, list); else rb_erase(&skb->rbnode, root); __kfree_skb(skb); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOLLAPSED); return next; } /* Insert skb into rb tree, ordered by TCP_SKB_CB(skb)->seq */ void tcp_rbtree_insert(struct rb_root *root, struct sk_buff *skb) { struct rb_node **p = &root->rb_node; struct rb_node *parent = NULL; struct sk_buff *skb1; while (*p) { parent = *p; skb1 = rb_to_skb(parent); if (before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb1)->seq)) p = &parent->rb_left; else p = &parent->rb_right; } rb_link_node(&skb->rbnode, parent, p); rb_insert_color(&skb->rbnode, root); } /* Collapse contiguous sequence of skbs head..tail with * sequence numbers start..end. * * If tail is NULL, this means until the end of the queue. * * Segments with FIN/SYN are not collapsed (only because this * simplifies code) */ static void tcp_collapse(struct sock *sk, struct sk_buff_head *list, struct rb_root *root, struct sk_buff *head, struct sk_buff *tail, u32 start, u32 end) { struct sk_buff *skb = head, *n; struct sk_buff_head tmp; bool end_of_skbs; /* First, check that queue is collapsible and find * the point where collapsing can be useful. */ restart: for (end_of_skbs = true; skb != NULL && skb != tail; skb = n) { n = tcp_skb_next(skb, list); /* No new bits? It is possible on ofo queue. */ if (!before(start, TCP_SKB_CB(skb)->end_seq)) { skb = tcp_collapse_one(sk, skb, list, root); if (!skb) break; goto restart; } /* The first skb to collapse is: * - not SYN/FIN and * - bloated or contains data before "start" or * overlaps to the next one and mptcp allow collapsing. */ if (!(TCP_SKB_CB(skb)->tcp_flags & (TCPHDR_SYN | TCPHDR_FIN)) && (tcp_win_from_space(sk, skb->truesize) > skb->len || before(TCP_SKB_CB(skb)->seq, start))) { end_of_skbs = false; break; } if (n && n != tail && mptcp_skb_can_collapse(skb, n) && TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(n)->seq) { end_of_skbs = false; break; } /* Decided to skip this, advance start seq. */ start = TCP_SKB_CB(skb)->end_seq; } if (end_of_skbs || (TCP_SKB_CB(skb)->tcp_flags & (TCPHDR_SYN | TCPHDR_FIN))) return; __skb_queue_head_init(&tmp); while (before(start, end)) { int copy = min_t(int, SKB_MAX_ORDER(0, 0), end - start); struct sk_buff *nskb; nskb = alloc_skb(copy, GFP_ATOMIC); if (!nskb) break; memcpy(nskb->cb, skb->cb, sizeof(skb->cb)); #ifdef CONFIG_TLS_DEVICE nskb->decrypted = skb->decrypted; #endif TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(nskb)->end_seq = start; if (list) __skb_queue_before(list, skb, nskb); else __skb_queue_tail(&tmp, nskb); /* defer rbtree insertion */ skb_set_owner_r(nskb, sk); mptcp_skb_ext_move(nskb, skb); /* Copy data, releasing collapsed skbs. */ while (copy > 0) { int offset = start - TCP_SKB_CB(skb)->seq; int size = TCP_SKB_CB(skb)->end_seq - start; BUG_ON(offset < 0); if (size > 0) { size = min(copy, size); if (skb_copy_bits(skb, offset, skb_put(nskb, size), size)) BUG(); TCP_SKB_CB(nskb)->end_seq += size; copy -= size; start += size; } if (!before(start, TCP_SKB_CB(skb)->end_seq)) { skb = tcp_collapse_one(sk, skb, list, root); if (!skb || skb == tail || !mptcp_skb_can_collapse(nskb, skb) || (TCP_SKB_CB(skb)->tcp_flags & (TCPHDR_SYN | TCPHDR_FIN))) goto end; #ifdef CONFIG_TLS_DEVICE if (skb->decrypted != nskb->decrypted) goto end; #endif } } } end: skb_queue_walk_safe(&tmp, skb, n) tcp_rbtree_insert(root, skb); } /* Collapse ofo queue. Algorithm: select contiguous sequence of skbs * and tcp_collapse() them until all the queue is collapsed. */ static void tcp_collapse_ofo_queue(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); u32 range_truesize, sum_tiny = 0; struct sk_buff *skb, *head; u32 start, end; skb = skb_rb_first(&tp->out_of_order_queue); new_range: if (!skb) { tp->ooo_last_skb = skb_rb_last(&tp->out_of_order_queue); return; } start = TCP_SKB_CB(skb)->seq; end = TCP_SKB_CB(skb)->end_seq; range_truesize = skb->truesize; for (head = skb;;) { skb = skb_rb_next(skb); /* Range is terminated when we see a gap or when * we are at the queue end. */ if (!skb || after(TCP_SKB_CB(skb)->seq, end) || before(TCP_SKB_CB(skb)->end_seq, start)) { /* Do not attempt collapsing tiny skbs */ if (range_truesize != head->truesize || end - start >= SKB_WITH_OVERHEAD(PAGE_SIZE)) { tcp_collapse(sk, NULL, &tp->out_of_order_queue, head, skb, start, end); } else { sum_tiny += range_truesize; if (sum_tiny > sk->sk_rcvbuf >> 3) return; } goto new_range; } range_truesize += skb->truesize; if (unlikely(before(TCP_SKB_CB(skb)->seq, start))) start = TCP_SKB_CB(skb)->seq; if (after(TCP_SKB_CB(skb)->end_seq, end)) end = TCP_SKB_CB(skb)->end_seq; } } /* * Clean the out-of-order queue to make room. * We drop high sequences packets to : * 1) Let a chance for holes to be filled. * This means we do not drop packets from ooo queue if their sequence * is before incoming packet sequence. * 2) not add too big latencies if thousands of packets sit there. * (But if application shrinks SO_RCVBUF, we could still end up * freeing whole queue here) * 3) Drop at least 12.5 % of sk_rcvbuf to avoid malicious attacks. * * Return true if queue has shrunk. */ static bool tcp_prune_ofo_queue(struct sock *sk, const struct sk_buff *in_skb) { struct tcp_sock *tp = tcp_sk(sk); struct rb_node *node, *prev; bool pruned = false; int goal; if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) return false; goal = sk->sk_rcvbuf >> 3; node = &tp->ooo_last_skb->rbnode; do { struct sk_buff *skb = rb_to_skb(node); /* If incoming skb would land last in ofo queue, stop pruning. */ if (after(TCP_SKB_CB(in_skb)->seq, TCP_SKB_CB(skb)->seq)) break; pruned = true; prev = rb_prev(node); rb_erase(node, &tp->out_of_order_queue); goal -= skb->truesize; tcp_drop_reason(sk, skb, SKB_DROP_REASON_TCP_OFO_QUEUE_PRUNE); tp->ooo_last_skb = rb_to_skb(prev); if (!prev || goal <= 0) { if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && !tcp_under_memory_pressure(sk)) break; goal = sk->sk_rcvbuf >> 3; } node = prev; } while (node); if (pruned) { NET_INC_STATS(sock_net(sk), LINUX_MIB_OFOPRUNED); /* Reset SACK state. A conforming SACK implementation will * do the same at a timeout based retransmit. When a connection * is in a sad state like this, we care only about integrity * of the connection not performance. */ if (tp->rx_opt.sack_ok) tcp_sack_reset(&tp->rx_opt); } return pruned; } /* Reduce allocated memory if we can, trying to get * the socket within its memory limits again. * * Return less than zero if we should start dropping frames * until the socket owning process reads some of the data * to stabilize the situation. */ static int tcp_prune_queue(struct sock *sk, const struct sk_buff *in_skb) { struct tcp_sock *tp = tcp_sk(sk); NET_INC_STATS(sock_net(sk), LINUX_MIB_PRUNECALLED); if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) tcp_clamp_window(sk); else if (tcp_under_memory_pressure(sk)) tcp_adjust_rcv_ssthresh(sk); if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) return 0; tcp_collapse_ofo_queue(sk); if (!skb_queue_empty(&sk->sk_receive_queue)) tcp_collapse(sk, &sk->sk_receive_queue, NULL, skb_peek(&sk->sk_receive_queue), NULL, tp->copied_seq, tp->rcv_nxt); if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) return 0; /* Collapsing did not help, destructive actions follow. * This must not ever occur. */ tcp_prune_ofo_queue(sk, in_skb); if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) return 0; /* If we are really being abused, tell the caller to silently * drop receive data on the floor. It will get retransmitted * and hopefully then we'll have sufficient space. */ NET_INC_STATS(sock_net(sk), LINUX_MIB_RCVPRUNED); /* Massive buffer overcommit. */ tp->pred_flags = 0; return -1; } static bool tcp_should_expand_sndbuf(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); /* If the user specified a specific send buffer setting, do * not modify it. */ if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) return false; /* If we are under global TCP memory pressure, do not expand. */ if (tcp_under_memory_pressure(sk)) { int unused_mem = sk_unused_reserved_mem(sk); /* Adjust sndbuf according to reserved mem. But make sure * it never goes below SOCK_MIN_SNDBUF. * See sk_stream_moderate_sndbuf() for more details. */ if (unused_mem > SOCK_MIN_SNDBUF) WRITE_ONCE(sk->sk_sndbuf, unused_mem); return false; } /* If we are under soft global TCP memory pressure, do not expand. */ if (sk_memory_allocated(sk) >= sk_prot_mem_limits(sk, 0)) return false; /* If we filled the congestion window, do not expand. */ if (tcp_packets_in_flight(tp) >= tcp_snd_cwnd(tp)) return false; return true; } static void tcp_new_space(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); if (tcp_should_expand_sndbuf(sk)) { tcp_sndbuf_expand(sk); tp->snd_cwnd_stamp = tcp_jiffies32; } INDIRECT_CALL_1(sk->sk_write_space, sk_stream_write_space, sk); } /* Caller made space either from: * 1) Freeing skbs in rtx queues (after tp->snd_una has advanced) * 2) Sent skbs from output queue (and thus advancing tp->snd_nxt) * * We might be able to generate EPOLLOUT to the application if: * 1) Space consumed in output/rtx queues is below sk->sk_sndbuf/2 * 2) notsent amount (tp->write_seq - tp->snd_nxt) became * small enough that tcp_stream_memory_free() decides it * is time to generate EPOLLOUT. */ void tcp_check_space(struct sock *sk) { /* pairs with tcp_poll() */ smp_mb(); if (sk->sk_socket && test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { tcp_new_space(sk); if (!test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED); } } static inline void tcp_data_snd_check(struct sock *sk) { tcp_push_pending_frames(sk); tcp_check_space(sk); } /* * Check if sending an ack is needed. */ static void __tcp_ack_snd_check(struct sock *sk, int ofo_possible) { struct tcp_sock *tp = tcp_sk(sk); unsigned long rtt, delay; /* More than one full frame received... */ if (((tp->rcv_nxt - tp->rcv_wup) > inet_csk(sk)->icsk_ack.rcv_mss && /* ... and right edge of window advances far enough. * (tcp_recvmsg() will send ACK otherwise). * If application uses SO_RCVLOWAT, we want send ack now if * we have not received enough bytes to satisfy the condition. */ (tp->rcv_nxt - tp->copied_seq < sk->sk_rcvlowat || __tcp_select_window(sk) >= tp->rcv_wnd)) || /* We ACK each frame or... */ tcp_in_quickack_mode(sk) || /* Protocol state mandates a one-time immediate ACK */ inet_csk(sk)->icsk_ack.pending & ICSK_ACK_NOW) { send_now: tcp_send_ack(sk); return; } if (!ofo_possible || RB_EMPTY_ROOT(&tp->out_of_order_queue)) { tcp_send_delayed_ack(sk); return; } if (!tcp_is_sack(tp) || tp->compressed_ack >= READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_comp_sack_nr)) goto send_now; if (tp->compressed_ack_rcv_nxt != tp->rcv_nxt) { tp->compressed_ack_rcv_nxt = tp->rcv_nxt; tp->dup_ack_counter = 0; } if (tp->dup_ack_counter < TCP_FASTRETRANS_THRESH) { tp->dup_ack_counter++; goto send_now; } tp->compressed_ack++; if (hrtimer_is_queued(&tp->compressed_ack_timer)) return; /* compress ack timer : 5 % of rtt, but no more than tcp_comp_sack_delay_ns */ rtt = tp->rcv_rtt_est.rtt_us; if (tp->srtt_us && tp->srtt_us < rtt) rtt = tp->srtt_us; delay = min_t(unsigned long, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_comp_sack_delay_ns), rtt * (NSEC_PER_USEC >> 3)/20); sock_hold(sk); hrtimer_start_range_ns(&tp->compressed_ack_timer, ns_to_ktime(delay), READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_comp_sack_slack_ns), HRTIMER_MODE_REL_PINNED_SOFT); } static inline void tcp_ack_snd_check(struct sock *sk) { if (!inet_csk_ack_scheduled(sk)) { /* We sent a data segment already. */ return; } __tcp_ack_snd_check(sk, 1); } /* * This routine is only called when we have urgent data * signaled. Its the 'slow' part of tcp_urg. It could be * moved inline now as tcp_urg is only called from one * place. We handle URGent data wrong. We have to - as * BSD still doesn't use the correction from RFC961. * For 1003.1g we should support a new option TCP_STDURG to permit * either form (or just set the sysctl tcp_stdurg). */ static void tcp_check_urg(struct sock *sk, const struct tcphdr *th) { struct tcp_sock *tp = tcp_sk(sk); u32 ptr = ntohs(th->urg_ptr); if (ptr && !READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_stdurg)) ptr--; ptr += ntohl(th->seq); /* Ignore urgent data that we've already seen and read. */ if (after(tp->copied_seq, ptr)) return; /* Do not replay urg ptr. * * NOTE: interesting situation not covered by specs. * Misbehaving sender may send urg ptr, pointing to segment, * which we already have in ofo queue. We are not able to fetch * such data and will stay in TCP_URG_NOTYET until will be eaten * by recvmsg(). Seems, we are not obliged to handle such wicked * situations. But it is worth to think about possibility of some * DoSes using some hypothetical application level deadlock. */ if (before(ptr, tp->rcv_nxt)) return; /* Do we already have a newer (or duplicate) urgent pointer? */ if (tp->urg_data && !after(ptr, tp->urg_seq)) return; /* Tell the world about our new urgent pointer. */ sk_send_sigurg(sk); /* We may be adding urgent data when the last byte read was * urgent. To do this requires some care. We cannot just ignore * tp->copied_seq since we would read the last urgent byte again * as data, nor can we alter copied_seq until this data arrives * or we break the semantics of SIOCATMARK (and thus sockatmark()) * * NOTE. Double Dutch. Rendering to plain English: author of comment * above did something sort of send("A", MSG_OOB); send("B", MSG_OOB); * and expect that both A and B disappear from stream. This is _wrong_. * Though this happens in BSD with high probability, this is occasional. * Any application relying on this is buggy. Note also, that fix "works" * only in this artificial test. Insert some normal data between A and B and we will * decline of BSD again. Verdict: it is better to remove to trap * buggy users. */ if (tp->urg_seq == tp->copied_seq && tp->urg_data && !sock_flag(sk, SOCK_URGINLINE) && tp->copied_seq != tp->rcv_nxt) { struct sk_buff *skb = skb_peek(&sk->sk_receive_queue); tp->copied_seq++; if (skb && !before(tp->copied_seq, TCP_SKB_CB(skb)->end_seq)) { __skb_unlink(skb, &sk->sk_receive_queue); __kfree_skb(skb); } } WRITE_ONCE(tp->urg_data, TCP_URG_NOTYET); WRITE_ONCE(tp->urg_seq, ptr); /* Disable header prediction. */ tp->pred_flags = 0; } /* This is the 'fast' part of urgent handling. */ static void tcp_urg(struct sock *sk, struct sk_buff *skb, const struct tcphdr *th) { struct tcp_sock *tp = tcp_sk(sk); /* Check if we get a new urgent pointer - normally not. */ if (unlikely(th->urg)) tcp_check_urg(sk, th); /* Do we wait for any urgent data? - normally not... */ if (unlikely(tp->urg_data == TCP_URG_NOTYET)) { u32 ptr = tp->urg_seq - ntohl(th->seq) + (th->doff * 4) - th->syn; /* Is the urgent pointer pointing into this packet? */ if (ptr < skb->len) { u8 tmp; if (skb_copy_bits(skb, ptr, &tmp, 1)) BUG(); WRITE_ONCE(tp->urg_data, TCP_URG_VALID | tmp); if (!sock_flag(sk, SOCK_DEAD)) sk->sk_data_ready(sk); } } } /* Accept RST for rcv_nxt - 1 after a FIN. * When tcp connections are abruptly terminated from Mac OSX (via ^C), a * FIN is sent followed by a RST packet. The RST is sent with the same * sequence number as the FIN, and thus according to RFC 5961 a challenge * ACK should be sent. However, Mac OSX rate limits replies to challenge * ACKs on the closed socket. In addition middleboxes can drop either the * challenge ACK or a subsequent RST. */ static bool tcp_reset_check(const struct sock *sk, const struct sk_buff *skb) { const struct tcp_sock *tp = tcp_sk(sk); return unlikely(TCP_SKB_CB(skb)->seq == (tp->rcv_nxt - 1) && (1 << sk->sk_state) & (TCPF_CLOSE_WAIT | TCPF_LAST_ACK | TCPF_CLOSING)); } /* Does PAWS and seqno based validation of an incoming segment, flags will * play significant role here. */ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb, const struct tcphdr *th, int syn_inerr) { struct tcp_sock *tp = tcp_sk(sk); SKB_DR(reason); /* RFC1323: H1. Apply PAWS check first. */ if (tcp_fast_parse_options(sock_net(sk), skb, th, tp) && tp->rx_opt.saw_tstamp && tcp_paws_discard(sk, skb)) { if (!th->rst) { if (unlikely(th->syn)) goto syn_challenge; NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSESTABREJECTED); if (!tcp_oow_rate_limited(sock_net(sk), skb, LINUX_MIB_TCPACKSKIPPEDPAWS, &tp->last_oow_ack_time)) tcp_send_dupack(sk, skb); SKB_DR_SET(reason, TCP_RFC7323_PAWS); goto discard; } /* Reset is accepted even if it did not pass PAWS. */ } /* Step 1: check sequence number */ reason = tcp_sequence(tp, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq); if (reason) { /* RFC793, page 37: "In all states except SYN-SENT, all reset * (RST) segments are validated by checking their SEQ-fields." * And page 69: "If an incoming segment is not acceptable, * an acknowledgment should be sent in reply (unless the RST * bit is set, if so drop the segment and return)". */ if (!th->rst) { if (th->syn) goto syn_challenge; if (!tcp_oow_rate_limited(sock_net(sk), skb, LINUX_MIB_TCPACKSKIPPEDSEQ, &tp->last_oow_ack_time)) tcp_send_dupack(sk, skb); } else if (tcp_reset_check(sk, skb)) { goto reset; } goto discard; } /* Step 2: check RST bit */ if (th->rst) { /* RFC 5961 3.2 (extend to match against (RCV.NXT - 1) after a * FIN and SACK too if available): * If seq num matches RCV.NXT or (RCV.NXT - 1) after a FIN, or * the right-most SACK block, * then * RESET the connection * else * Send a challenge ACK */ if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt || tcp_reset_check(sk, skb)) goto reset; if (tcp_is_sack(tp) && tp->rx_opt.num_sacks > 0) { struct tcp_sack_block *sp = &tp->selective_acks[0]; int max_sack = sp[0].end_seq; int this_sack; for (this_sack = 1; this_sack < tp->rx_opt.num_sacks; ++this_sack) { max_sack = after(sp[this_sack].end_seq, max_sack) ? sp[this_sack].end_seq : max_sack; } if (TCP_SKB_CB(skb)->seq == max_sack) goto reset; } /* Disable TFO if RST is out-of-order * and no data has been received * for current active TFO socket */ if (tp->syn_fastopen && !tp->data_segs_in && sk->sk_state == TCP_ESTABLISHED) tcp_fastopen_active_disable(sk); tcp_send_challenge_ack(sk); SKB_DR_SET(reason, TCP_RESET); goto discard; } /* step 3: check security and precedence [ignored] */ /* step 4: Check for a SYN * RFC 5961 4.2 : Send a challenge ack */ if (th->syn) { syn_challenge: if (syn_inerr) TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNCHALLENGE); tcp_send_challenge_ack(sk); SKB_DR_SET(reason, TCP_INVALID_SYN); goto discard; } bpf_skops_parse_hdr(sk, skb); return true; discard: tcp_drop_reason(sk, skb, reason); return false; reset: tcp_reset(sk, skb); __kfree_skb(skb); return false; } /* * TCP receive function for the ESTABLISHED state. * * It is split into a fast path and a slow path. The fast path is * disabled when: * - A zero window was announced from us - zero window probing * is only handled properly in the slow path. * - Out of order segments arrived. * - Urgent data is expected. * - There is no buffer space left * - Unexpected TCP flags/window values/header lengths are received * (detected by checking the TCP header against pred_flags) * - Data is sent in both directions. Fast path only supports pure senders * or pure receivers (this means either the sequence number or the ack * value must stay constant) * - Unexpected TCP option. * * When these conditions are not satisfied it drops into a standard * receive procedure patterned after RFC793 to handle all cases. * The first three cases are guaranteed by proper pred_flags setting, * the rest is checked inline. Fast processing is turned on in * tcp_data_queue when everything is OK. */ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb) { enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED; const struct tcphdr *th = (const struct tcphdr *)skb->data; struct tcp_sock *tp = tcp_sk(sk); unsigned int len = skb->len; /* TCP congestion window tracking */ trace_tcp_probe(sk, skb); tcp_mstamp_refresh(tp); if (unlikely(!rcu_access_pointer(sk->sk_rx_dst))) inet_csk(sk)->icsk_af_ops->sk_rx_dst_set(sk, skb); /* * Header prediction. * The code loosely follows the one in the famous * "30 instruction TCP receive" Van Jacobson mail. * * Van's trick is to deposit buffers into socket queue * on a device interrupt, to call tcp_recv function * on the receive process context and checksum and copy * the buffer to user space. smart... * * Our current scheme is not silly either but we take the * extra cost of the net_bh soft interrupt processing... * We do checksum and copy also but from device to kernel. */ tp->rx_opt.saw_tstamp = 0; /* pred_flags is 0xS?10 << 16 + snd_wnd * if header_prediction is to be made * 'S' will always be tp->tcp_header_len >> 2 * '?' will be 0 for the fast path, otherwise pred_flags is 0 to * turn it off (when there are holes in the receive * space for instance) * PSH flag is ignored. */ if ((tcp_flag_word(th) & TCP_HP_BITS) == tp->pred_flags && TCP_SKB_CB(skb)->seq == tp->rcv_nxt && !after(TCP_SKB_CB(skb)->ack_seq, tp->snd_nxt)) { int tcp_header_len = tp->tcp_header_len; /* Timestamp header prediction: tcp_header_len * is automatically equal to th->doff*4 due to pred_flags * match. */ /* Check timestamp */ if (tcp_header_len == sizeof(struct tcphdr) + TCPOLEN_TSTAMP_ALIGNED) { /* No? Slow path! */ if (!tcp_parse_aligned_timestamp(tp, th)) goto slow_path; /* If PAWS failed, check it more carefully in slow path */ if ((s32)(tp->rx_opt.rcv_tsval - tp->rx_opt.ts_recent) < 0) goto slow_path; /* DO NOT update ts_recent here, if checksum fails * and timestamp was corrupted part, it will result * in a hung connection since we will drop all * future packets due to the PAWS test. */ } if (len <= tcp_header_len) { /* Bulk data transfer: sender */ if (len == tcp_header_len) { /* Predicted packet is in window by definition. * seq == rcv_nxt and rcv_wup <= rcv_nxt. * Hence, check seq<=rcv_wup reduces to: */ if (tcp_header_len == (sizeof(struct tcphdr) + TCPOLEN_TSTAMP_ALIGNED) && tp->rcv_nxt == tp->rcv_wup) tcp_store_ts_recent(tp); /* We know that such packets are checksummed * on entry. */ tcp_ack(sk, skb, 0); __kfree_skb(skb); tcp_data_snd_check(sk); /* When receiving pure ack in fast path, update * last ts ecr directly instead of calling * tcp_rcv_rtt_measure_ts() */ tp->rcv_rtt_last_tsecr = tp->rx_opt.rcv_tsecr; return; } else { /* Header too small */ reason = SKB_DROP_REASON_PKT_TOO_SMALL; TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); goto discard; } } else { int eaten = 0; bool fragstolen = false; if (tcp_checksum_complete(skb)) goto csum_error; if ((int)skb->truesize > sk->sk_forward_alloc) goto step5; /* Predicted packet is in window by definition. * seq == rcv_nxt and rcv_wup <= rcv_nxt. * Hence, check seq<=rcv_wup reduces to: */ if (tcp_header_len == (sizeof(struct tcphdr) + TCPOLEN_TSTAMP_ALIGNED) && tp->rcv_nxt == tp->rcv_wup) tcp_store_ts_recent(tp); tcp_rcv_rtt_measure_ts(sk, skb); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHPHITS); /* Bulk data transfer: receiver */ skb_dst_drop(skb); __skb_pull(skb, tcp_header_len); eaten = tcp_queue_rcv(sk, skb, &fragstolen); tcp_event_data_recv(sk, skb); if (TCP_SKB_CB(skb)->ack_seq != tp->snd_una) { /* Well, only one small jumplet in fast path... */ tcp_ack(sk, skb, FLAG_DATA); tcp_data_snd_check(sk); if (!inet_csk_ack_scheduled(sk)) goto no_ack; } else { tcp_update_wl(tp, TCP_SKB_CB(skb)->seq); } __tcp_ack_snd_check(sk, 0); no_ack: if (eaten) kfree_skb_partial(skb, fragstolen); tcp_data_ready(sk); return; } } slow_path: if (len < (th->doff << 2) || tcp_checksum_complete(skb)) goto csum_error; if (!th->ack && !th->rst && !th->syn) { reason = SKB_DROP_REASON_TCP_FLAGS; goto discard; } /* * Standard slow path. */ if (!tcp_validate_incoming(sk, skb, th, 1)) return; step5: reason = tcp_ack(sk, skb, FLAG_SLOWPATH | FLAG_UPDATE_TS_RECENT); if ((int)reason < 0) { reason = -reason; goto discard; } tcp_rcv_rtt_measure_ts(sk, skb); /* Process urgent data. */ tcp_urg(sk, skb, th); /* step 7: process the segment text */ tcp_data_queue(sk, skb); tcp_data_snd_check(sk); tcp_ack_snd_check(sk); return; csum_error: reason = SKB_DROP_REASON_TCP_CSUM; trace_tcp_bad_csum(skb); TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); discard: tcp_drop_reason(sk, skb, reason); } EXPORT_SYMBOL(tcp_rcv_established); void tcp_init_transfer(struct sock *sk, int bpf_op, struct sk_buff *skb) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); tcp_mtup_init(sk); icsk->icsk_af_ops->rebuild_header(sk); tcp_init_metrics(sk); /* Initialize the congestion window to start the transfer. * Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been * retransmitted. In light of RFC6298 more aggressive 1sec * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK * retransmission has occurred. */ if (tp->total_retrans > 1 && tp->undo_marker) tcp_snd_cwnd_set(tp, 1); else tcp_snd_cwnd_set(tp, tcp_init_cwnd(tp, __sk_dst_get(sk))); tp->snd_cwnd_stamp = tcp_jiffies32; bpf_skops_established(sk, bpf_op, skb); /* Initialize congestion control unless BPF initialized it already: */ if (!icsk->icsk_ca_initialized) tcp_init_congestion_control(sk); tcp_init_buffer_space(sk); } void tcp_finish_connect(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); tcp_set_state(sk, TCP_ESTABLISHED); icsk->icsk_ack.lrcvtime = tcp_jiffies32; if (skb) { icsk->icsk_af_ops->sk_rx_dst_set(sk, skb); security_inet_conn_established(sk, skb); sk_mark_napi_id(sk, skb); } tcp_init_transfer(sk, BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB, skb); /* Prevent spurious tcp_cwnd_restart() on first data * packet. */ tp->lsndtime = tcp_jiffies32; if (sock_flag(sk, SOCK_KEEPOPEN)) inet_csk_reset_keepalive_timer(sk, keepalive_time_when(tp)); if (!tp->rx_opt.snd_wscale) __tcp_fast_path_on(tp, tp->snd_wnd); else tp->pred_flags = 0; } static bool tcp_rcv_fastopen_synack(struct sock *sk, struct sk_buff *synack, struct tcp_fastopen_cookie *cookie) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *data = tp->syn_data ? tcp_rtx_queue_head(sk) : NULL; u16 mss = tp->rx_opt.mss_clamp, try_exp = 0; bool syn_drop = false; if (mss == tp->rx_opt.user_mss) { struct tcp_options_received opt; /* Get original SYNACK MSS value if user MSS sets mss_clamp */ tcp_clear_options(&opt); opt.user_mss = opt.mss_clamp = 0; tcp_parse_options(sock_net(sk), synack, &opt, 0, NULL); mss = opt.mss_clamp; } if (!tp->syn_fastopen) { /* Ignore an unsolicited cookie */ cookie->len = -1; } else if (tp->total_retrans) { /* SYN timed out and the SYN-ACK neither has a cookie nor * acknowledges data. Presumably the remote received only * the retransmitted (regular) SYNs: either the original * SYN-data or the corresponding SYN-ACK was dropped. */ syn_drop = (cookie->len < 0 && data); } else if (cookie->len < 0 && !tp->syn_data) { /* We requested a cookie but didn't get it. If we did not use * the (old) exp opt format then try so next time (try_exp=1). * Otherwise we go back to use the RFC7413 opt (try_exp=2). */ try_exp = tp->syn_fastopen_exp ? 2 : 1; } tcp_fastopen_cache_set(sk, mss, cookie, syn_drop, try_exp); if (data) { /* Retransmit unacked data in SYN */ if (tp->total_retrans) tp->fastopen_client_fail = TFO_SYN_RETRANSMITTED; else tp->fastopen_client_fail = TFO_DATA_NOT_ACKED; skb_rbtree_walk_from(data) tcp_mark_skb_lost(sk, data); tcp_xmit_retransmit_queue(sk); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENACTIVEFAIL); return true; } tp->syn_data_acked = tp->syn_data; if (tp->syn_data_acked) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENACTIVE); /* SYN-data is counted as two separate packets in tcp_ack() */ if (tp->delivered > 1) --tp->delivered; } tcp_fastopen_add_skb(sk, synack); return false; } static void smc_check_reset_syn(struct tcp_sock *tp) { #if IS_ENABLED(CONFIG_SMC) if (static_branch_unlikely(&tcp_have_smc)) { if (tp->syn_smc && !tp->rx_opt.smc_ok) tp->syn_smc = 0; } #endif } static void tcp_try_undo_spurious_syn(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); u32 syn_stamp; /* undo_marker is set when SYN or SYNACK times out. The timeout is * spurious if the ACK's timestamp option echo value matches the * original SYN timestamp. */ syn_stamp = tp->retrans_stamp; if (tp->undo_marker && syn_stamp && tp->rx_opt.saw_tstamp && syn_stamp == tp->rx_opt.rcv_tsecr) tp->undo_marker = 0; } static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb, const struct tcphdr *th) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct tcp_fastopen_cookie foc = { .len = -1 }; int saved_clamp = tp->rx_opt.mss_clamp; bool fastopen_fail; SKB_DR(reason); tcp_parse_options(sock_net(sk), skb, &tp->rx_opt, 0, &foc); if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr) tp->rx_opt.rcv_tsecr -= tp->tsoffset; if (th->ack) { /* rfc793: * "If the state is SYN-SENT then * first check the ACK bit * If the ACK bit is set * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send * a reset (unless the RST bit is set, if so drop * the segment and return)" */ if (!after(TCP_SKB_CB(skb)->ack_seq, tp->snd_una) || after(TCP_SKB_CB(skb)->ack_seq, tp->snd_nxt)) { /* Previous FIN/ACK or RST/ACK might be ignored. */ if (icsk->icsk_retransmits == 0) inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, TCP_TIMEOUT_MIN, TCP_RTO_MAX); goto reset_and_undo; } if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr && !between(tp->rx_opt.rcv_tsecr, tp->retrans_stamp, tcp_time_stamp(tp))) { NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSACTIVEREJECTED); goto reset_and_undo; } /* Now ACK is acceptable. * * "If the RST bit is set * If the ACK was acceptable then signal the user "error: * connection reset", drop the segment, enter CLOSED state, * delete TCB, and return." */ if (th->rst) { tcp_reset(sk, skb); consume: __kfree_skb(skb); return 0; } /* rfc793: * "fifth, if neither of the SYN or RST bits is set then * drop the segment and return." * * See note below! * --ANK(990513) */ if (!th->syn) { SKB_DR_SET(reason, TCP_FLAGS); goto discard_and_undo; } /* rfc793: * "If the SYN bit is on ... * are acceptable then ... * (our SYN has been ACKed), change the connection * state to ESTABLISHED..." */ tcp_ecn_rcv_synack(tp, th); tcp_init_wl(tp, TCP_SKB_CB(skb)->seq); tcp_try_undo_spurious_syn(sk); tcp_ack(sk, skb, FLAG_SLOWPATH); /* Ok.. it's good. Set up sequence numbers and * move to established. */ WRITE_ONCE(tp->rcv_nxt, TCP_SKB_CB(skb)->seq + 1); tp->rcv_wup = TCP_SKB_CB(skb)->seq + 1; /* RFC1323: The window in SYN & SYN/ACK segments is * never scaled. */ tp->snd_wnd = ntohs(th->window); if (!tp->rx_opt.wscale_ok) { tp->rx_opt.snd_wscale = tp->rx_opt.rcv_wscale = 0; tp->window_clamp = min(tp->window_clamp, 65535U); } if (tp->rx_opt.saw_tstamp) { tp->rx_opt.tstamp_ok = 1; tp->tcp_header_len = sizeof(struct tcphdr) + TCPOLEN_TSTAMP_ALIGNED; tp->advmss -= TCPOLEN_TSTAMP_ALIGNED; tcp_store_ts_recent(tp); } else { tp->tcp_header_len = sizeof(struct tcphdr); } tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); tcp_initialize_rcv_mss(sk); /* Remember, tcp_poll() does not lock socket! * Change state from SYN-SENT only after copied_seq * is initialized. */ WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); smc_check_reset_syn(tp); smp_mb(); tcp_finish_connect(sk, skb); fastopen_fail = (tp->syn_fastopen || tp->syn_data) && tcp_rcv_fastopen_synack(sk, skb, &foc); if (!sock_flag(sk, SOCK_DEAD)) { sk->sk_state_change(sk); sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT); } if (fastopen_fail) return -1; if (sk->sk_write_pending || READ_ONCE(icsk->icsk_accept_queue.rskq_defer_accept) || inet_csk_in_pingpong_mode(sk)) { /* Save one ACK. Data will be ready after * several ticks, if write_pending is set. * * It may be deleted, but with this feature tcpdumps * look so _wonderfully_ clever, that I was not able * to stand against the temptation 8) --ANK */ inet_csk_schedule_ack(sk); tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, TCP_DELACK_MAX, TCP_RTO_MAX); goto consume; } tcp_send_ack(sk); return -1; } /* No ACK in the segment */ if (th->rst) { /* rfc793: * "If the RST bit is set * * Otherwise (no ACK) drop the segment and return." */ SKB_DR_SET(reason, TCP_RESET); goto discard_and_undo; } /* PAWS check. */ if (tp->rx_opt.ts_recent_stamp && tp->rx_opt.saw_tstamp && tcp_paws_reject(&tp->rx_opt, 0)) { SKB_DR_SET(reason, TCP_RFC7323_PAWS); goto discard_and_undo; } if (th->syn) { /* We see SYN without ACK. It is attempt of * simultaneous connect with crossed SYNs. * Particularly, it can be connect to self. */ tcp_set_state(sk, TCP_SYN_RECV); if (tp->rx_opt.saw_tstamp) { tp->rx_opt.tstamp_ok = 1; tcp_store_ts_recent(tp); tp->tcp_header_len = sizeof(struct tcphdr) + TCPOLEN_TSTAMP_ALIGNED; } else { tp->tcp_header_len = sizeof(struct tcphdr); } WRITE_ONCE(tp->rcv_nxt, TCP_SKB_CB(skb)->seq + 1); WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); tp->rcv_wup = TCP_SKB_CB(skb)->seq + 1; /* RFC1323: The window in SYN & SYN/ACK segments is * never scaled. */ tp->snd_wnd = ntohs(th->window); tp->snd_wl1 = TCP_SKB_CB(skb)->seq; tp->max_window = tp->snd_wnd; tcp_ecn_rcv_syn(tp, th); tcp_mtup_init(sk); tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); tcp_initialize_rcv_mss(sk); tcp_send_synack(sk); #if 0 /* Note, we could accept data and URG from this segment. * There are no obstacles to make this (except that we must * either change tcp_recvmsg() to prevent it from returning data * before 3WHS completes per RFC793, or employ TCP Fast Open). * * However, if we ignore data in ACKless segments sometimes, * we have no reasons to accept it sometimes. * Also, seems the code doing it in step6 of tcp_rcv_state_process * is not flawless. So, discard packet for sanity. * Uncomment this return to process the data. */ return -1; #else goto consume; #endif } /* "fifth, if neither of the SYN or RST bits is set then * drop the segment and return." */ discard_and_undo: tcp_clear_options(&tp->rx_opt); tp->rx_opt.mss_clamp = saved_clamp; tcp_drop_reason(sk, skb, reason); return 0; reset_and_undo: tcp_clear_options(&tp->rx_opt); tp->rx_opt.mss_clamp = saved_clamp; return 1; } static void tcp_rcv_synrecv_state_fastopen(struct sock *sk) { struct request_sock *req; /* If we are still handling the SYNACK RTO, see if timestamp ECR allows * undo. If peer SACKs triggered fast recovery, we can't undo here. */ if (inet_csk(sk)->icsk_ca_state == TCP_CA_Loss) tcp_try_undo_loss(sk, false); /* Reset rtx states to prevent spurious retransmits_timed_out() */ tcp_sk(sk)->retrans_stamp = 0; inet_csk(sk)->icsk_retransmits = 0; /* Once we leave TCP_SYN_RECV or TCP_FIN_WAIT_1, * we no longer need req so release it. */ req = rcu_dereference_protected(tcp_sk(sk)->fastopen_rsk, lockdep_sock_is_held(sk)); reqsk_fastopen_remove(sk, req, false); /* Re-arm the timer because data may have been sent out. * This is similar to the regular data transmission case * when new data has just been ack'ed. * * (TFO) - we could try to be more aggressive and * retransmitting any data sooner based on when they * are sent out. */ tcp_rearm_rto(sk); } /* * This function implements the receiving procedure of RFC 793 for * all states except ESTABLISHED and TIME_WAIT. * It's called from both tcp_v4_rcv and tcp_v6_rcv and should be * address independent. */ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); const struct tcphdr *th = tcp_hdr(skb); struct request_sock *req; int queued = 0; bool acceptable; SKB_DR(reason); switch (sk->sk_state) { case TCP_CLOSE: SKB_DR_SET(reason, TCP_CLOSE); goto discard; case TCP_LISTEN: if (th->ack) return 1; if (th->rst) { SKB_DR_SET(reason, TCP_RESET); goto discard; } if (th->syn) { if (th->fin) { SKB_DR_SET(reason, TCP_FLAGS); goto discard; } /* It is possible that we process SYN packets from backlog, * so we need to make sure to disable BH and RCU right there. */ rcu_read_lock(); local_bh_disable(); acceptable = icsk->icsk_af_ops->conn_request(sk, skb) >= 0; local_bh_enable(); rcu_read_unlock(); if (!acceptable) return 1; consume_skb(skb); return 0; } SKB_DR_SET(reason, TCP_FLAGS); goto discard; case TCP_SYN_SENT: tp->rx_opt.saw_tstamp = 0; tcp_mstamp_refresh(tp); queued = tcp_rcv_synsent_state_process(sk, skb, th); if (queued >= 0) return queued; /* Do step6 onward by hand. */ tcp_urg(sk, skb, th); __kfree_skb(skb); tcp_data_snd_check(sk); return 0; } tcp_mstamp_refresh(tp); tp->rx_opt.saw_tstamp = 0; req = rcu_dereference_protected(tp->fastopen_rsk, lockdep_sock_is_held(sk)); if (req) { bool req_stolen; WARN_ON_ONCE(sk->sk_state != TCP_SYN_RECV && sk->sk_state != TCP_FIN_WAIT1); if (!tcp_check_req(sk, skb, req, true, &req_stolen)) { SKB_DR_SET(reason, TCP_FASTOPEN); goto discard; } } if (!th->ack && !th->rst && !th->syn) { SKB_DR_SET(reason, TCP_FLAGS); goto discard; } if (!tcp_validate_incoming(sk, skb, th, 0)) return 0; /* step 5: check the ACK field */ acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH | FLAG_UPDATE_TS_RECENT | FLAG_NO_CHALLENGE_ACK) > 0; if (!acceptable) { if (sk->sk_state == TCP_SYN_RECV) return 1; /* send one RST */ tcp_send_challenge_ack(sk); SKB_DR_SET(reason, TCP_OLD_ACK); goto discard; } switch (sk->sk_state) { case TCP_SYN_RECV: tp->delivered++; /* SYN-ACK delivery isn't tracked in tcp_ack */ if (!tp->srtt_us) tcp_synack_rtt_meas(sk, req); if (req) { tcp_rcv_synrecv_state_fastopen(sk); } else { tcp_try_undo_spurious_syn(sk); tp->retrans_stamp = 0; tcp_init_transfer(sk, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB, skb); WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); } smp_mb(); tcp_set_state(sk, TCP_ESTABLISHED); sk->sk_state_change(sk); /* Note, that this wakeup is only for marginal crossed SYN case. * Passively open sockets are not waked up, because * sk->sk_sleep == NULL and sk->sk_socket == NULL. */ if (sk->sk_socket) sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT); tp->snd_una = TCP_SKB_CB(skb)->ack_seq; tp->snd_wnd = ntohs(th->window) << tp->rx_opt.snd_wscale; tcp_init_wl(tp, TCP_SKB_CB(skb)->seq); if (tp->rx_opt.tstamp_ok) tp->advmss -= TCPOLEN_TSTAMP_ALIGNED; if (!inet_csk(sk)->icsk_ca_ops->cong_control) tcp_update_pacing_rate(sk); /* Prevent spurious tcp_cwnd_restart() on first data packet */ tp->lsndtime = tcp_jiffies32; tcp_initialize_rcv_mss(sk); tcp_fast_path_on(tp); break; case TCP_FIN_WAIT1: { int tmo; if (req) tcp_rcv_synrecv_state_fastopen(sk); if (tp->snd_una != tp->write_seq) break; tcp_set_state(sk, TCP_FIN_WAIT2); WRITE_ONCE(sk->sk_shutdown, sk->sk_shutdown | SEND_SHUTDOWN); sk_dst_confirm(sk); if (!sock_flag(sk, SOCK_DEAD)) { /* Wake up lingering close() */ sk->sk_state_change(sk); break; } if (READ_ONCE(tp->linger2) < 0) { tcp_done(sk); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA); return 1; } if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq && after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt)) { /* Receive out of order FIN after close() */ if (tp->syn_fastopen && th->fin) tcp_fastopen_active_disable(sk); tcp_done(sk); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA); return 1; } tmo = tcp_fin_time(sk); if (tmo > TCP_TIMEWAIT_LEN) { inet_csk_reset_keepalive_timer(sk, tmo - TCP_TIMEWAIT_LEN); } else if (th->fin || sock_owned_by_user(sk)) { /* Bad case. We could lose such FIN otherwise. * It is not a big problem, but it looks confusing * and not so rare event. We still can lose it now, * if it spins in bh_lock_sock(), but it is really * marginal case. */ inet_csk_reset_keepalive_timer(sk, tmo); } else { tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); goto consume; } break; } case TCP_CLOSING: if (tp->snd_una == tp->write_seq) { tcp_time_wait(sk, TCP_TIME_WAIT, 0); goto consume; } break; case TCP_LAST_ACK: if (tp->snd_una == tp->write_seq) { tcp_update_metrics(sk); tcp_done(sk); goto consume; } break; } /* step 6: check the URG bit */ tcp_urg(sk, skb, th); /* step 7: process the segment text */ switch (sk->sk_state) { case TCP_CLOSE_WAIT: case TCP_CLOSING: case TCP_LAST_ACK: if (!before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) { /* If a subflow has been reset, the packet should not * continue to be processed, drop the packet. */ if (sk_is_mptcp(sk) && !mptcp_incoming_options(sk, skb)) goto discard; break; } fallthrough; case TCP_FIN_WAIT1: case TCP_FIN_WAIT2: /* RFC 793 says to queue data in these states, * RFC 1122 says we MUST send a reset. * BSD 4.4 also does reset. */ if (sk->sk_shutdown & RCV_SHUTDOWN) { if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq && after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA); tcp_reset(sk, skb); return 1; } } fallthrough; case TCP_ESTABLISHED: tcp_data_queue(sk, skb); queued = 1; break; } /* tcp_data could move socket to TIME-WAIT */ if (sk->sk_state != TCP_CLOSE) { tcp_data_snd_check(sk); tcp_ack_snd_check(sk); } if (!queued) { discard: tcp_drop_reason(sk, skb, reason); } return 0; consume: __kfree_skb(skb); return 0; } EXPORT_SYMBOL(tcp_rcv_state_process); static inline void pr_drop_req(struct request_sock *req, __u16 port, int family) { struct inet_request_sock *ireq = inet_rsk(req); if (family == AF_INET) net_dbg_ratelimited("drop open request from %pI4/%u\n", &ireq->ir_rmt_addr, port); #if IS_ENABLED(CONFIG_IPV6) else if (family == AF_INET6) net_dbg_ratelimited("drop open request from %pI6/%u\n", &ireq->ir_v6_rmt_addr, port); #endif } /* RFC3168 : 6.1.1 SYN packets must not have ECT/ECN bits set * * If we receive a SYN packet with these bits set, it means a * network is playing bad games with TOS bits. In order to * avoid possible false congestion notifications, we disable * TCP ECN negotiation. * * Exception: tcp_ca wants ECN. This is required for DCTCP * congestion control: Linux DCTCP asserts ECT on all packets, * including SYN, which is most optimal solution; however, * others, such as FreeBSD do not. * * Exception: At least one of the reserved bits of the TCP header (th->res1) is * set, indicating the use of a future TCP extension (such as AccECN). See * RFC8311 §4.3 which updates RFC3168 to allow the development of such * extensions. */ static void tcp_ecn_create_request(struct request_sock *req, const struct sk_buff *skb, const struct sock *listen_sk, const struct dst_entry *dst) { const struct tcphdr *th = tcp_hdr(skb); const struct net *net = sock_net(listen_sk); bool th_ecn = th->ece && th->cwr; bool ect, ecn_ok; u32 ecn_ok_dst; if (!th_ecn) return; ect = !INET_ECN_is_not_ect(TCP_SKB_CB(skb)->ip_dsfield); ecn_ok_dst = dst_feature(dst, DST_FEATURE_ECN_MASK); ecn_ok = READ_ONCE(net->ipv4.sysctl_tcp_ecn) || ecn_ok_dst; if (((!ect || th->res1) && ecn_ok) || tcp_ca_needs_ecn(listen_sk) || (ecn_ok_dst & DST_FEATURE_ECN_CA) || tcp_bpf_ca_needs_ecn((struct sock *)req)) inet_rsk(req)->ecn_ok = 1; } static void tcp_openreq_init(struct request_sock *req, const struct tcp_options_received *rx_opt, struct sk_buff *skb, const struct sock *sk) { struct inet_request_sock *ireq = inet_rsk(req); req->rsk_rcv_wnd = 0; /* So that tcp_send_synack() knows! */ tcp_rsk(req)->rcv_isn = TCP_SKB_CB(skb)->seq; tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->seq + 1; tcp_rsk(req)->snt_synack = 0; tcp_rsk(req)->last_oow_ack_time = 0; req->mss = rx_opt->mss_clamp; req->ts_recent = rx_opt->saw_tstamp ? rx_opt->rcv_tsval : 0; ireq->tstamp_ok = rx_opt->tstamp_ok; ireq->sack_ok = rx_opt->sack_ok; ireq->snd_wscale = rx_opt->snd_wscale; ireq->wscale_ok = rx_opt->wscale_ok; ireq->acked = 0; ireq->ecn_ok = 0; ireq->ir_rmt_port = tcp_hdr(skb)->source; ireq->ir_num = ntohs(tcp_hdr(skb)->dest); ireq->ir_mark = inet_request_mark(sk, skb); #if IS_ENABLED(CONFIG_SMC) ireq->smc_ok = rx_opt->smc_ok && !(tcp_sk(sk)->smc_hs_congested && tcp_sk(sk)->smc_hs_congested(sk)); #endif } struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops, struct sock *sk_listener, bool attach_listener) { struct request_sock *req = reqsk_alloc(ops, sk_listener, attach_listener); if (req) { struct inet_request_sock *ireq = inet_rsk(req); ireq->ireq_opt = NULL; #if IS_ENABLED(CONFIG_IPV6) ireq->pktopts = NULL; #endif atomic64_set(&ireq->ir_cookie, 0); ireq->ireq_state = TCP_NEW_SYN_RECV; write_pnet(&ireq->ireq_net, sock_net(sk_listener)); ireq->ireq_family = sk_listener->sk_family; req->timeout = TCP_TIMEOUT_INIT; } return req; } EXPORT_SYMBOL(inet_reqsk_alloc); /* * Return true if a syncookie should be sent */ static bool tcp_syn_flood_action(const struct sock *sk, const char *proto) { struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; const char *msg = "Dropping request"; struct net *net = sock_net(sk); bool want_cookie = false; u8 syncookies; syncookies = READ_ONCE(net->ipv4.sysctl_tcp_syncookies); #ifdef CONFIG_SYN_COOKIES if (syncookies) { msg = "Sending cookies"; want_cookie = true; __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPREQQFULLDOCOOKIES); } else #endif __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPREQQFULLDROP); if (!READ_ONCE(queue->synflood_warned) && syncookies != 2 && xchg(&queue->synflood_warned, 1) == 0) { if (IS_ENABLED(CONFIG_IPV6) && sk->sk_family == AF_INET6) { net_info_ratelimited("%s: Possible SYN flooding on port [%pI6c]:%u. %s.\n", proto, inet6_rcv_saddr(sk), sk->sk_num, msg); } else { net_info_ratelimited("%s: Possible SYN flooding on port %pI4:%u. %s.\n", proto, &sk->sk_rcv_saddr, sk->sk_num, msg); } } return want_cookie; } static void tcp_reqsk_record_syn(const struct sock *sk, struct request_sock *req, const struct sk_buff *skb) { if (tcp_sk(sk)->save_syn) { u32 len = skb_network_header_len(skb) + tcp_hdrlen(skb); struct saved_syn *saved_syn; u32 mac_hdrlen; void *base; if (tcp_sk(sk)->save_syn == 2) { /* Save full header. */ base = skb_mac_header(skb); mac_hdrlen = skb_mac_header_len(skb); len += mac_hdrlen; } else { base = skb_network_header(skb); mac_hdrlen = 0; } saved_syn = kmalloc(struct_size(saved_syn, data, len), GFP_ATOMIC); if (saved_syn) { saved_syn->mac_hdrlen = mac_hdrlen; saved_syn->network_hdrlen = skb_network_header_len(skb); saved_syn->tcp_hdrlen = tcp_hdrlen(skb); memcpy(saved_syn->data, base, len); req->saved_syn = saved_syn; } } } /* If a SYN cookie is required and supported, returns a clamped MSS value to be * used for SYN cookie generation. */ u16 tcp_get_syncookie_mss(struct request_sock_ops *rsk_ops, const struct tcp_request_sock_ops *af_ops, struct sock *sk, struct tcphdr *th) { struct tcp_sock *tp = tcp_sk(sk); u16 mss; if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies) != 2 && !inet_csk_reqsk_queue_is_full(sk)) return 0; if (!tcp_syn_flood_action(sk, rsk_ops->slab_name)) return 0; if (sk_acceptq_is_full(sk)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); return 0; } mss = tcp_parse_mss_option(th, tp->rx_opt.user_mss); if (!mss) mss = af_ops->mss_clamp; return mss; } EXPORT_SYMBOL_GPL(tcp_get_syncookie_mss); int tcp_conn_request(struct request_sock_ops *rsk_ops, const struct tcp_request_sock_ops *af_ops, struct sock *sk, struct sk_buff *skb) { struct tcp_fastopen_cookie foc = { .len = -1 }; __u32 isn = TCP_SKB_CB(skb)->tcp_tw_isn; struct tcp_options_received tmp_opt; struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); struct sock *fastopen_sk = NULL; struct request_sock *req; bool want_cookie = false; struct dst_entry *dst; struct flowi fl; u8 syncookies; syncookies = READ_ONCE(net->ipv4.sysctl_tcp_syncookies); /* TW buckets are converted to open requests without * limitations, they conserve resources and peer is * evidently real one. */ if ((syncookies == 2 || inet_csk_reqsk_queue_is_full(sk)) && !isn) { want_cookie = tcp_syn_flood_action(sk, rsk_ops->slab_name); if (!want_cookie) goto drop; } if (sk_acceptq_is_full(sk)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); goto drop; } req = inet_reqsk_alloc(rsk_ops, sk, !want_cookie); if (!req) goto drop; req->syncookie = want_cookie; tcp_rsk(req)->af_specific = af_ops; tcp_rsk(req)->ts_off = 0; #if IS_ENABLED(CONFIG_MPTCP) tcp_rsk(req)->is_mptcp = 0; #endif tcp_clear_options(&tmp_opt); tmp_opt.mss_clamp = af_ops->mss_clamp; tmp_opt.user_mss = tp->rx_opt.user_mss; tcp_parse_options(sock_net(sk), skb, &tmp_opt, 0, want_cookie ? NULL : &foc); if (want_cookie && !tmp_opt.saw_tstamp) tcp_clear_options(&tmp_opt); if (IS_ENABLED(CONFIG_SMC) && want_cookie) tmp_opt.smc_ok = 0; tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; tcp_openreq_init(req, &tmp_opt, skb, sk); inet_rsk(req)->no_srccheck = inet_test_bit(TRANSPARENT, sk); /* Note: tcp_v6_init_req() might override ir_iif for link locals */ inet_rsk(req)->ir_iif = inet_request_bound_dev_if(sk, skb); dst = af_ops->route_req(sk, skb, &fl, req); if (!dst) goto drop_and_free; if (tmp_opt.tstamp_ok) tcp_rsk(req)->ts_off = af_ops->init_ts_off(net, skb); if (!want_cookie && !isn) { int max_syn_backlog = READ_ONCE(net->ipv4.sysctl_max_syn_backlog); /* Kill the following clause, if you dislike this way. */ if (!syncookies && (max_syn_backlog - inet_csk_reqsk_queue_len(sk) < (max_syn_backlog >> 2)) && !tcp_peer_is_proven(req, dst)) { /* Without syncookies last quarter of * backlog is filled with destinations, * proven to be alive. * It means that we continue to communicate * to destinations, already remembered * to the moment of synflood. */ pr_drop_req(req, ntohs(tcp_hdr(skb)->source), rsk_ops->family); goto drop_and_release; } isn = af_ops->init_seq(skb); } tcp_ecn_create_request(req, skb, sk, dst); if (want_cookie) { isn = cookie_init_sequence(af_ops, sk, skb, &req->mss); if (!tmp_opt.tstamp_ok) inet_rsk(req)->ecn_ok = 0; } tcp_rsk(req)->snt_isn = isn; tcp_rsk(req)->txhash = net_tx_rndhash(); tcp_rsk(req)->syn_tos = TCP_SKB_CB(skb)->ip_dsfield; tcp_openreq_init_rwin(req, sk, dst); sk_rx_queue_set(req_to_sk(req), skb); if (!want_cookie) { tcp_reqsk_record_syn(sk, req, skb); fastopen_sk = tcp_try_fastopen(sk, skb, req, &foc, dst); } if (fastopen_sk) { af_ops->send_synack(fastopen_sk, dst, &fl, req, &foc, TCP_SYNACK_FASTOPEN, skb); /* Add the child socket directly into the accept queue */ if (!inet_csk_reqsk_queue_add(sk, req, fastopen_sk)) { reqsk_fastopen_remove(fastopen_sk, req, false); bh_unlock_sock(fastopen_sk); sock_put(fastopen_sk); goto drop_and_free; } sk->sk_data_ready(sk); bh_unlock_sock(fastopen_sk); sock_put(fastopen_sk); } else { tcp_rsk(req)->tfo_listener = false; if (!want_cookie) { req->timeout = tcp_timeout_init((struct sock *)req); inet_csk_reqsk_queue_hash_add(sk, req, req->timeout); } af_ops->send_synack(sk, dst, &fl, req, &foc, !want_cookie ? TCP_SYNACK_NORMAL : TCP_SYNACK_COOKIE, skb); if (want_cookie) { reqsk_free(req); return 0; } } reqsk_put(req); return 0; drop_and_release: dst_release(dst); drop_and_free: __reqsk_free(req); drop: tcp_listendrop(sk); return 0; } EXPORT_SYMBOL(tcp_conn_request);
linux-master
net/ipv4/tcp_input.c
// SPDX-License-Identifier: GPL-2.0-only /* * CAIA Delay-Gradient (CDG) congestion control * * This implementation is based on the paper: * D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using * delay gradients." In IFIP Networking, pages 328-341. Springer, 2011. * * Scavenger traffic (Less-than-Best-Effort) should disable coexistence * heuristics using parameters use_shadow=0 and use_ineff=0. * * Parameters window, backoff_beta, and backoff_factor are crucial for * throughput and delay. Future work is needed to determine better defaults, * and to provide guidelines for use in different environments/contexts. * * Except for window, knobs are configured via /sys/module/tcp_cdg/parameters/. * Parameter window is only configurable when loading tcp_cdg as a module. * * Notable differences from paper/FreeBSD: * o Using Hybrid Slow start and Proportional Rate Reduction. * o Add toggle for shadow window mechanism. Suggested by David Hayes. * o Add toggle for non-congestion loss tolerance. * o Scaling parameter G is changed to a backoff factor; * conversion is given by: backoff_factor = 1000/(G * window). * o Limit shadow window to 2 * cwnd, or to cwnd when application limited. * o More accurate e^-x. */ #include <linux/kernel.h> #include <linux/random.h> #include <linux/module.h> #include <linux/sched/clock.h> #include <net/tcp.h> #define HYSTART_ACK_TRAIN 1 #define HYSTART_DELAY 2 static int window __read_mostly = 8; static unsigned int backoff_beta __read_mostly = 0.7071 * 1024; /* sqrt 0.5 */ static unsigned int backoff_factor __read_mostly = 42; static unsigned int hystart_detect __read_mostly = 3; static unsigned int use_ineff __read_mostly = 5; static bool use_shadow __read_mostly = true; static bool use_tolerance __read_mostly; module_param(window, int, 0444); MODULE_PARM_DESC(window, "gradient window size (power of two <= 256)"); module_param(backoff_beta, uint, 0644); MODULE_PARM_DESC(backoff_beta, "backoff beta (0-1024)"); module_param(backoff_factor, uint, 0644); MODULE_PARM_DESC(backoff_factor, "backoff probability scale factor"); module_param(hystart_detect, uint, 0644); MODULE_PARM_DESC(hystart_detect, "use Hybrid Slow start " "(0: disabled, 1: ACK train, 2: delay threshold, 3: both)"); module_param(use_ineff, uint, 0644); MODULE_PARM_DESC(use_ineff, "use ineffectual backoff detection (threshold)"); module_param(use_shadow, bool, 0644); MODULE_PARM_DESC(use_shadow, "use shadow window heuristic"); module_param(use_tolerance, bool, 0644); MODULE_PARM_DESC(use_tolerance, "use loss tolerance heuristic"); struct cdg_minmax { union { struct { s32 min; s32 max; }; u64 v64; }; }; enum cdg_state { CDG_UNKNOWN = 0, CDG_NONFULL = 1, CDG_FULL = 2, CDG_BACKOFF = 3, }; struct cdg { struct cdg_minmax rtt; struct cdg_minmax rtt_prev; struct cdg_minmax *gradients; struct cdg_minmax gsum; bool gfilled; u8 tail; u8 state; u8 delack; u32 rtt_seq; u32 shadow_wnd; u16 backoff_cnt; u16 sample_cnt; s32 delay_min; u32 last_ack; u32 round_start; }; /** * nexp_u32 - negative base-e exponential * @ux: x in units of micro * * Returns exp(ux * -1e-6) * U32_MAX. */ static u32 __pure nexp_u32(u32 ux) { static const u16 v[] = { /* exp(-x)*65536-1 for x = 0, 0.000256, 0.000512, ... */ 65535, 65518, 65501, 65468, 65401, 65267, 65001, 64470, 63422, 61378, 57484, 50423, 38795, 22965, 8047, 987, 14, }; u32 msb = ux >> 8; u32 res; int i; /* Cut off when ux >= 2^24 (actual result is <= 222/U32_MAX). */ if (msb > U16_MAX) return 0; /* Scale first eight bits linearly: */ res = U32_MAX - (ux & 0xff) * (U32_MAX / 1000000); /* Obtain e^(x + y + ...) by computing e^x * e^y * ...: */ for (i = 1; msb; i++, msb >>= 1) { u32 y = v[i & -(msb & 1)] + U32_C(1); res = ((u64)res * y) >> 16; } return res; } /* Based on the HyStart algorithm (by Ha et al.) that is implemented in * tcp_cubic. Differences/experimental changes: * o Using Hayes' delayed ACK filter. * o Using a usec clock for the ACK train. * o Reset ACK train when application limited. * o Invoked at any cwnd (i.e. also when cwnd < 16). * o Invoked only when cwnd < ssthresh (i.e. not when cwnd == ssthresh). */ static void tcp_cdg_hystart_update(struct sock *sk) { struct cdg *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); ca->delay_min = min_not_zero(ca->delay_min, ca->rtt.min); if (ca->delay_min == 0) return; if (hystart_detect & HYSTART_ACK_TRAIN) { u32 now_us = tp->tcp_mstamp; if (ca->last_ack == 0 || !tcp_is_cwnd_limited(sk)) { ca->last_ack = now_us; ca->round_start = now_us; } else if (before(now_us, ca->last_ack + 3000)) { u32 base_owd = max(ca->delay_min / 2U, 125U); ca->last_ack = now_us; if (after(now_us, ca->round_start + base_owd)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHYSTARTTRAINDETECT); NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPHYSTARTTRAINCWND, tcp_snd_cwnd(tp)); tp->snd_ssthresh = tcp_snd_cwnd(tp); return; } } } if (hystart_detect & HYSTART_DELAY) { if (ca->sample_cnt < 8) { ca->sample_cnt++; } else { s32 thresh = max(ca->delay_min + ca->delay_min / 8U, 125U); if (ca->rtt.min > thresh) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHYSTARTDELAYDETECT); NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPHYSTARTDELAYCWND, tcp_snd_cwnd(tp)); tp->snd_ssthresh = tcp_snd_cwnd(tp); } } } } static s32 tcp_cdg_grad(struct cdg *ca) { s32 gmin = ca->rtt.min - ca->rtt_prev.min; s32 gmax = ca->rtt.max - ca->rtt_prev.max; s32 grad; if (ca->gradients) { ca->gsum.min += gmin - ca->gradients[ca->tail].min; ca->gsum.max += gmax - ca->gradients[ca->tail].max; ca->gradients[ca->tail].min = gmin; ca->gradients[ca->tail].max = gmax; ca->tail = (ca->tail + 1) & (window - 1); gmin = ca->gsum.min; gmax = ca->gsum.max; } /* We keep sums to ignore gradients during cwnd reductions; * the paper's smoothed gradients otherwise simplify to: * (rtt_latest - rtt_oldest) / window. * * We also drop division by window here. */ grad = gmin > 0 ? gmin : gmax; /* Extrapolate missing values in gradient window: */ if (!ca->gfilled) { if (!ca->gradients && window > 1) grad *= window; /* Memory allocation failed. */ else if (ca->tail == 0) ca->gfilled = true; else grad = (grad * window) / (int)ca->tail; } /* Backoff was effectual: */ if (gmin <= -32 || gmax <= -32) ca->backoff_cnt = 0; if (use_tolerance) { /* Reduce small variations to zero: */ gmin = DIV_ROUND_CLOSEST(gmin, 64); gmax = DIV_ROUND_CLOSEST(gmax, 64); if (gmin > 0 && gmax <= 0) ca->state = CDG_FULL; else if ((gmin > 0 && gmax > 0) || gmax < 0) ca->state = CDG_NONFULL; } return grad; } static bool tcp_cdg_backoff(struct sock *sk, u32 grad) { struct cdg *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); if (get_random_u32() <= nexp_u32(grad * backoff_factor)) return false; if (use_ineff) { ca->backoff_cnt++; if (ca->backoff_cnt > use_ineff) return false; } ca->shadow_wnd = max(ca->shadow_wnd, tcp_snd_cwnd(tp)); ca->state = CDG_BACKOFF; tcp_enter_cwr(sk); return true; } /* Not called in CWR or Recovery state. */ static void tcp_cdg_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct cdg *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); u32 prior_snd_cwnd; u32 incr; if (tcp_in_slow_start(tp) && hystart_detect) tcp_cdg_hystart_update(sk); if (after(ack, ca->rtt_seq) && ca->rtt.v64) { s32 grad = 0; if (ca->rtt_prev.v64) grad = tcp_cdg_grad(ca); ca->rtt_seq = tp->snd_nxt; ca->rtt_prev = ca->rtt; ca->rtt.v64 = 0; ca->last_ack = 0; ca->sample_cnt = 0; if (grad > 0 && tcp_cdg_backoff(sk, grad)) return; } if (!tcp_is_cwnd_limited(sk)) { ca->shadow_wnd = min(ca->shadow_wnd, tcp_snd_cwnd(tp)); return; } prior_snd_cwnd = tcp_snd_cwnd(tp); tcp_reno_cong_avoid(sk, ack, acked); incr = tcp_snd_cwnd(tp) - prior_snd_cwnd; ca->shadow_wnd = max(ca->shadow_wnd, ca->shadow_wnd + incr); } static void tcp_cdg_acked(struct sock *sk, const struct ack_sample *sample) { struct cdg *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); if (sample->rtt_us <= 0) return; /* A heuristic for filtering delayed ACKs, adapted from: * D.A. Hayes. "Timing enhancements to the FreeBSD kernel to support * delay and rate based TCP mechanisms." TR 100219A. CAIA, 2010. */ if (tp->sacked_out == 0) { if (sample->pkts_acked == 1 && ca->delack) { /* A delayed ACK is only used for the minimum if it is * provenly lower than an existing non-zero minimum. */ ca->rtt.min = min(ca->rtt.min, sample->rtt_us); ca->delack--; return; } else if (sample->pkts_acked > 1 && ca->delack < 5) { ca->delack++; } } ca->rtt.min = min_not_zero(ca->rtt.min, sample->rtt_us); ca->rtt.max = max(ca->rtt.max, sample->rtt_us); } static u32 tcp_cdg_ssthresh(struct sock *sk) { struct cdg *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); if (ca->state == CDG_BACKOFF) return max(2U, (tcp_snd_cwnd(tp) * min(1024U, backoff_beta)) >> 10); if (ca->state == CDG_NONFULL && use_tolerance) return tcp_snd_cwnd(tp); ca->shadow_wnd = min(ca->shadow_wnd >> 1, tcp_snd_cwnd(tp)); if (use_shadow) return max3(2U, ca->shadow_wnd, tcp_snd_cwnd(tp) >> 1); return max(2U, tcp_snd_cwnd(tp) >> 1); } static void tcp_cdg_cwnd_event(struct sock *sk, const enum tcp_ca_event ev) { struct cdg *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); struct cdg_minmax *gradients; switch (ev) { case CA_EVENT_CWND_RESTART: gradients = ca->gradients; if (gradients) memset(gradients, 0, window * sizeof(gradients[0])); memset(ca, 0, sizeof(*ca)); ca->gradients = gradients; ca->rtt_seq = tp->snd_nxt; ca->shadow_wnd = tcp_snd_cwnd(tp); break; case CA_EVENT_COMPLETE_CWR: ca->state = CDG_UNKNOWN; ca->rtt_seq = tp->snd_nxt; ca->rtt_prev = ca->rtt; ca->rtt.v64 = 0; break; default: break; } } static void tcp_cdg_init(struct sock *sk) { struct cdg *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); ca->gradients = NULL; /* We silently fall back to window = 1 if allocation fails. */ if (window > 1) ca->gradients = kcalloc(window, sizeof(ca->gradients[0]), GFP_NOWAIT | __GFP_NOWARN); ca->rtt_seq = tp->snd_nxt; ca->shadow_wnd = tcp_snd_cwnd(tp); } static void tcp_cdg_release(struct sock *sk) { struct cdg *ca = inet_csk_ca(sk); kfree(ca->gradients); ca->gradients = NULL; } static struct tcp_congestion_ops tcp_cdg __read_mostly = { .cong_avoid = tcp_cdg_cong_avoid, .cwnd_event = tcp_cdg_cwnd_event, .pkts_acked = tcp_cdg_acked, .undo_cwnd = tcp_reno_undo_cwnd, .ssthresh = tcp_cdg_ssthresh, .release = tcp_cdg_release, .init = tcp_cdg_init, .owner = THIS_MODULE, .name = "cdg", }; static int __init tcp_cdg_register(void) { if (backoff_beta > 1024 || window < 1 || window > 256) return -ERANGE; if (!is_power_of_2(window)) return -EINVAL; BUILD_BUG_ON(sizeof(struct cdg) > ICSK_CA_PRIV_SIZE); tcp_register_congestion_control(&tcp_cdg); return 0; } static void __exit tcp_cdg_unregister(void) { tcp_unregister_congestion_control(&tcp_cdg); } module_init(tcp_cdg_register); module_exit(tcp_cdg_unregister); MODULE_AUTHOR("Kenneth Klette Jonassen"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("TCP CDG");
linux-master
net/ipv4/tcp_cdg.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * Linux NET3: Internet Group Management Protocol [IGMP] * * This code implements the IGMP protocol as defined in RFC1112. There has * been a further revision of this protocol since which is now supported. * * If you have trouble with this module be careful what gcc you have used, * the older version didn't come out right using gcc 2.5.8, the newer one * seems to fall out with gcc 2.6.2. * * Authors: * Alan Cox <[email protected]> * * Fixes: * * Alan Cox : Added lots of __inline__ to optimise * the memory usage of all the tiny little * functions. * Alan Cox : Dumped the header building experiment. * Alan Cox : Minor tweaks ready for multicast routing * and extended IGMP protocol. * Alan Cox : Removed a load of inline directives. Gcc 2.5.8 * writes utterly bogus code otherwise (sigh) * fixed IGMP loopback to behave in the manner * desired by mrouted, fixed the fact it has been * broken since 1.3.6 and cleaned up a few minor * points. * * Chih-Jen Chang : Tried to revise IGMP to Version 2 * Tsu-Sheng Tsao E-mail: [email protected] and [email protected] * The enhancements are mainly based on Steve Deering's * ipmulti-3.5 source code. * Chih-Jen Chang : Added the igmp_get_mrouter_info and * Tsu-Sheng Tsao igmp_set_mrouter_info to keep track of * the mrouted version on that device. * Chih-Jen Chang : Added the max_resp_time parameter to * Tsu-Sheng Tsao igmp_heard_query(). Using this parameter * to identify the multicast router version * and do what the IGMP version 2 specified. * Chih-Jen Chang : Added a timer to revert to IGMP V2 router * Tsu-Sheng Tsao if the specified time expired. * Alan Cox : Stop IGMP from 0.0.0.0 being accepted. * Alan Cox : Use GFP_ATOMIC in the right places. * Christian Daudt : igmp timer wasn't set for local group * memberships but was being deleted, * which caused a "del_timer() called * from %p with timer not initialized\n" * message (960131). * Christian Daudt : removed del_timer from * igmp_timer_expire function (960205). * Christian Daudt : igmp_heard_report now only calls * igmp_timer_expire if tm->running is * true (960216). * Malcolm Beattie : ttl comparison wrong in igmp_rcv made * igmp_heard_query never trigger. Expiry * miscalculation fixed in igmp_heard_query * and random() made to return unsigned to * prevent negative expiry times. * Alexey Kuznetsov: Wrong group leaving behaviour, backport * fix from pending 2.1.x patches. * Alan Cox: Forget to enable FDDI support earlier. * Alexey Kuznetsov: Fixed leaving groups on device down. * Alexey Kuznetsov: Accordance to igmp-v2-06 draft. * David L Stevens: IGMPv3 support, with help from * Vinay Kulkarni */ #include <linux/module.h> #include <linux/slab.h> #include <linux/uaccess.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/jiffies.h> #include <linux/string.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/in.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <linux/inetdevice.h> #include <linux/igmp.h> #include <linux/if_arp.h> #include <linux/rtnetlink.h> #include <linux/times.h> #include <linux/pkt_sched.h> #include <linux/byteorder/generic.h> #include <net/net_namespace.h> #include <net/arp.h> #include <net/ip.h> #include <net/protocol.h> #include <net/route.h> #include <net/sock.h> #include <net/checksum.h> #include <net/inet_common.h> #include <linux/netfilter_ipv4.h> #ifdef CONFIG_IP_MROUTE #include <linux/mroute.h> #endif #ifdef CONFIG_PROC_FS #include <linux/proc_fs.h> #include <linux/seq_file.h> #endif #ifdef CONFIG_IP_MULTICAST /* Parameter names and values are taken from igmp-v2-06 draft */ #define IGMP_QUERY_INTERVAL (125*HZ) #define IGMP_QUERY_RESPONSE_INTERVAL (10*HZ) #define IGMP_INITIAL_REPORT_DELAY (1) /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs! * IGMP specs require to report membership immediately after * joining a group, but we delay the first report by a * small interval. It seems more natural and still does not * contradict to specs provided this delay is small enough. */ #define IGMP_V1_SEEN(in_dev) \ (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \ IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \ ((in_dev)->mr_v1_seen && \ time_before(jiffies, (in_dev)->mr_v1_seen))) #define IGMP_V2_SEEN(in_dev) \ (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \ IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \ ((in_dev)->mr_v2_seen && \ time_before(jiffies, (in_dev)->mr_v2_seen))) static int unsolicited_report_interval(struct in_device *in_dev) { int interval_ms, interval_jiffies; if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) interval_ms = IN_DEV_CONF_GET( in_dev, IGMPV2_UNSOLICITED_REPORT_INTERVAL); else /* v3 */ interval_ms = IN_DEV_CONF_GET( in_dev, IGMPV3_UNSOLICITED_REPORT_INTERVAL); interval_jiffies = msecs_to_jiffies(interval_ms); /* _timer functions can't handle a delay of 0 jiffies so ensure * we always return a positive value. */ if (interval_jiffies <= 0) interval_jiffies = 1; return interval_jiffies; } static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im, gfp_t gfp); static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im); static void igmpv3_clear_delrec(struct in_device *in_dev); static int sf_setstate(struct ip_mc_list *pmc); static void sf_markstate(struct ip_mc_list *pmc); #endif static void ip_mc_clear_src(struct ip_mc_list *pmc); static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, int sfcount, __be32 *psfsrc, int delta); static void ip_ma_put(struct ip_mc_list *im) { if (refcount_dec_and_test(&im->refcnt)) { in_dev_put(im->interface); kfree_rcu(im, rcu); } } #define for_each_pmc_rcu(in_dev, pmc) \ for (pmc = rcu_dereference(in_dev->mc_list); \ pmc != NULL; \ pmc = rcu_dereference(pmc->next_rcu)) #define for_each_pmc_rtnl(in_dev, pmc) \ for (pmc = rtnl_dereference(in_dev->mc_list); \ pmc != NULL; \ pmc = rtnl_dereference(pmc->next_rcu)) static void ip_sf_list_clear_all(struct ip_sf_list *psf) { struct ip_sf_list *next; while (psf) { next = psf->sf_next; kfree(psf); psf = next; } } #ifdef CONFIG_IP_MULTICAST /* * Timer management */ static void igmp_stop_timer(struct ip_mc_list *im) { spin_lock_bh(&im->lock); if (del_timer(&im->timer)) refcount_dec(&im->refcnt); im->tm_running = 0; im->reporter = 0; im->unsolicit_count = 0; spin_unlock_bh(&im->lock); } /* It must be called with locked im->lock */ static void igmp_start_timer(struct ip_mc_list *im, int max_delay) { int tv = get_random_u32_below(max_delay); im->tm_running = 1; if (!mod_timer(&im->timer, jiffies+tv+2)) refcount_inc(&im->refcnt); } static void igmp_gq_start_timer(struct in_device *in_dev) { int tv = get_random_u32_below(in_dev->mr_maxdelay); unsigned long exp = jiffies + tv + 2; if (in_dev->mr_gq_running && time_after_eq(exp, (in_dev->mr_gq_timer).expires)) return; in_dev->mr_gq_running = 1; if (!mod_timer(&in_dev->mr_gq_timer, exp)) in_dev_hold(in_dev); } static void igmp_ifc_start_timer(struct in_device *in_dev, int delay) { int tv = get_random_u32_below(delay); if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2)) in_dev_hold(in_dev); } static void igmp_mod_timer(struct ip_mc_list *im, int max_delay) { spin_lock_bh(&im->lock); im->unsolicit_count = 0; if (del_timer(&im->timer)) { if ((long)(im->timer.expires-jiffies) < max_delay) { add_timer(&im->timer); im->tm_running = 1; spin_unlock_bh(&im->lock); return; } refcount_dec(&im->refcnt); } igmp_start_timer(im, max_delay); spin_unlock_bh(&im->lock); } /* * Send an IGMP report. */ #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4) static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type, int gdeleted, int sdeleted) { switch (type) { case IGMPV3_MODE_IS_INCLUDE: case IGMPV3_MODE_IS_EXCLUDE: if (gdeleted || sdeleted) return 0; if (!(pmc->gsquery && !psf->sf_gsresp)) { if (pmc->sfmode == MCAST_INCLUDE) return 1; /* don't include if this source is excluded * in all filters */ if (psf->sf_count[MCAST_INCLUDE]) return type == IGMPV3_MODE_IS_INCLUDE; return pmc->sfcount[MCAST_EXCLUDE] == psf->sf_count[MCAST_EXCLUDE]; } return 0; case IGMPV3_CHANGE_TO_INCLUDE: if (gdeleted || sdeleted) return 0; return psf->sf_count[MCAST_INCLUDE] != 0; case IGMPV3_CHANGE_TO_EXCLUDE: if (gdeleted || sdeleted) return 0; if (pmc->sfcount[MCAST_EXCLUDE] == 0 || psf->sf_count[MCAST_INCLUDE]) return 0; return pmc->sfcount[MCAST_EXCLUDE] == psf->sf_count[MCAST_EXCLUDE]; case IGMPV3_ALLOW_NEW_SOURCES: if (gdeleted || !psf->sf_crcount) return 0; return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted; case IGMPV3_BLOCK_OLD_SOURCES: if (pmc->sfmode == MCAST_INCLUDE) return gdeleted || (psf->sf_crcount && sdeleted); return psf->sf_crcount && !gdeleted && !sdeleted; } return 0; } static int igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted) { struct ip_sf_list *psf; int scount = 0; for (psf = pmc->sources; psf; psf = psf->sf_next) { if (!is_in(pmc, psf, type, gdeleted, sdeleted)) continue; scount++; } return scount; } /* source address selection per RFC 3376 section 4.2.13 */ static __be32 igmpv3_get_srcaddr(struct net_device *dev, const struct flowi4 *fl4) { struct in_device *in_dev = __in_dev_get_rcu(dev); const struct in_ifaddr *ifa; if (!in_dev) return htonl(INADDR_ANY); in_dev_for_each_ifa_rcu(ifa, in_dev) { if (fl4->saddr == ifa->ifa_local) return fl4->saddr; } return htonl(INADDR_ANY); } static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu) { struct sk_buff *skb; struct rtable *rt; struct iphdr *pip; struct igmpv3_report *pig; struct net *net = dev_net(dev); struct flowi4 fl4; int hlen = LL_RESERVED_SPACE(dev); int tlen = dev->needed_tailroom; unsigned int size; size = min(mtu, IP_MAX_MTU); while (1) { skb = alloc_skb(size + hlen + tlen, GFP_ATOMIC | __GFP_NOWARN); if (skb) break; size >>= 1; if (size < 256) return NULL; } skb->priority = TC_PRIO_CONTROL; rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0, 0, 0, IPPROTO_IGMP, 0, dev->ifindex); if (IS_ERR(rt)) { kfree_skb(skb); return NULL; } skb_dst_set(skb, &rt->dst); skb->dev = dev; skb_reserve(skb, hlen); skb_tailroom_reserve(skb, mtu, tlen); skb_reset_network_header(skb); pip = ip_hdr(skb); skb_put(skb, sizeof(struct iphdr) + 4); pip->version = 4; pip->ihl = (sizeof(struct iphdr)+4)>>2; pip->tos = 0xc0; pip->frag_off = htons(IP_DF); pip->ttl = 1; pip->daddr = fl4.daddr; rcu_read_lock(); pip->saddr = igmpv3_get_srcaddr(dev, &fl4); rcu_read_unlock(); pip->protocol = IPPROTO_IGMP; pip->tot_len = 0; /* filled in later */ ip_select_ident(net, skb, NULL); ((u8 *)&pip[1])[0] = IPOPT_RA; ((u8 *)&pip[1])[1] = 4; ((u8 *)&pip[1])[2] = 0; ((u8 *)&pip[1])[3] = 0; skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4; skb_put(skb, sizeof(*pig)); pig = igmpv3_report_hdr(skb); pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT; pig->resv1 = 0; pig->csum = 0; pig->resv2 = 0; pig->ngrec = 0; return skb; } static int igmpv3_sendpack(struct sk_buff *skb) { struct igmphdr *pig = igmp_hdr(skb); const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb); pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen); return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb); } static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel) { return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel); } static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc, int type, struct igmpv3_grec **ppgr, unsigned int mtu) { struct net_device *dev = pmc->interface->dev; struct igmpv3_report *pih; struct igmpv3_grec *pgr; if (!skb) { skb = igmpv3_newpack(dev, mtu); if (!skb) return NULL; } pgr = skb_put(skb, sizeof(struct igmpv3_grec)); pgr->grec_type = type; pgr->grec_auxwords = 0; pgr->grec_nsrcs = 0; pgr->grec_mca = pmc->multiaddr; pih = igmpv3_report_hdr(skb); pih->ngrec = htons(ntohs(pih->ngrec)+1); *ppgr = pgr; return skb; } #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0) static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted) { struct net_device *dev = pmc->interface->dev; struct net *net = dev_net(dev); struct igmpv3_report *pih; struct igmpv3_grec *pgr = NULL; struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list; int scount, stotal, first, isquery, truncate; unsigned int mtu; if (pmc->multiaddr == IGMP_ALL_HOSTS) return skb; if (ipv4_is_local_multicast(pmc->multiaddr) && !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) return skb; mtu = READ_ONCE(dev->mtu); if (mtu < IPV4_MIN_MTU) return skb; isquery = type == IGMPV3_MODE_IS_INCLUDE || type == IGMPV3_MODE_IS_EXCLUDE; truncate = type == IGMPV3_MODE_IS_EXCLUDE || type == IGMPV3_CHANGE_TO_EXCLUDE; stotal = scount = 0; psf_list = sdeleted ? &pmc->tomb : &pmc->sources; if (!*psf_list) goto empty_source; pih = skb ? igmpv3_report_hdr(skb) : NULL; /* EX and TO_EX get a fresh packet, if needed */ if (truncate) { if (pih && pih->ngrec && AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) { if (skb) igmpv3_sendpack(skb); skb = igmpv3_newpack(dev, mtu); } } first = 1; psf_prev = NULL; for (psf = *psf_list; psf; psf = psf_next) { __be32 *psrc; psf_next = psf->sf_next; if (!is_in(pmc, psf, type, gdeleted, sdeleted)) { psf_prev = psf; continue; } /* Based on RFC3376 5.1. Should not send source-list change * records when there is a filter mode change. */ if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) || (!gdeleted && pmc->crcount)) && (type == IGMPV3_ALLOW_NEW_SOURCES || type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) goto decrease_sf_crcount; /* clear marks on query responses */ if (isquery) psf->sf_gsresp = 0; if (AVAILABLE(skb) < sizeof(__be32) + first*sizeof(struct igmpv3_grec)) { if (truncate && !first) break; /* truncate these */ if (pgr) pgr->grec_nsrcs = htons(scount); if (skb) igmpv3_sendpack(skb); skb = igmpv3_newpack(dev, mtu); first = 1; scount = 0; } if (first) { skb = add_grhead(skb, pmc, type, &pgr, mtu); first = 0; } if (!skb) return NULL; psrc = skb_put(skb, sizeof(__be32)); *psrc = psf->sf_inaddr; scount++; stotal++; if ((type == IGMPV3_ALLOW_NEW_SOURCES || type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) { decrease_sf_crcount: psf->sf_crcount--; if ((sdeleted || gdeleted) && psf->sf_crcount == 0) { if (psf_prev) psf_prev->sf_next = psf->sf_next; else *psf_list = psf->sf_next; kfree(psf); continue; } } psf_prev = psf; } empty_source: if (!stotal) { if (type == IGMPV3_ALLOW_NEW_SOURCES || type == IGMPV3_BLOCK_OLD_SOURCES) return skb; if (pmc->crcount || isquery) { /* make sure we have room for group header */ if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) { igmpv3_sendpack(skb); skb = NULL; /* add_grhead will get a new one */ } skb = add_grhead(skb, pmc, type, &pgr, mtu); } } if (pgr) pgr->grec_nsrcs = htons(scount); if (isquery) pmc->gsquery = 0; /* clear query state on report */ return skb; } static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc) { struct sk_buff *skb = NULL; struct net *net = dev_net(in_dev->dev); int type; if (!pmc) { rcu_read_lock(); for_each_pmc_rcu(in_dev, pmc) { if (pmc->multiaddr == IGMP_ALL_HOSTS) continue; if (ipv4_is_local_multicast(pmc->multiaddr) && !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) continue; spin_lock_bh(&pmc->lock); if (pmc->sfcount[MCAST_EXCLUDE]) type = IGMPV3_MODE_IS_EXCLUDE; else type = IGMPV3_MODE_IS_INCLUDE; skb = add_grec(skb, pmc, type, 0, 0); spin_unlock_bh(&pmc->lock); } rcu_read_unlock(); } else { spin_lock_bh(&pmc->lock); if (pmc->sfcount[MCAST_EXCLUDE]) type = IGMPV3_MODE_IS_EXCLUDE; else type = IGMPV3_MODE_IS_INCLUDE; skb = add_grec(skb, pmc, type, 0, 0); spin_unlock_bh(&pmc->lock); } if (!skb) return 0; return igmpv3_sendpack(skb); } /* * remove zero-count source records from a source filter list */ static void igmpv3_clear_zeros(struct ip_sf_list **ppsf) { struct ip_sf_list *psf_prev, *psf_next, *psf; psf_prev = NULL; for (psf = *ppsf; psf; psf = psf_next) { psf_next = psf->sf_next; if (psf->sf_crcount == 0) { if (psf_prev) psf_prev->sf_next = psf->sf_next; else *ppsf = psf->sf_next; kfree(psf); } else psf_prev = psf; } } static void kfree_pmc(struct ip_mc_list *pmc) { ip_sf_list_clear_all(pmc->sources); ip_sf_list_clear_all(pmc->tomb); kfree(pmc); } static void igmpv3_send_cr(struct in_device *in_dev) { struct ip_mc_list *pmc, *pmc_prev, *pmc_next; struct sk_buff *skb = NULL; int type, dtype; rcu_read_lock(); spin_lock_bh(&in_dev->mc_tomb_lock); /* deleted MCA's */ pmc_prev = NULL; for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) { pmc_next = pmc->next; if (pmc->sfmode == MCAST_INCLUDE) { type = IGMPV3_BLOCK_OLD_SOURCES; dtype = IGMPV3_BLOCK_OLD_SOURCES; skb = add_grec(skb, pmc, type, 1, 0); skb = add_grec(skb, pmc, dtype, 1, 1); } if (pmc->crcount) { if (pmc->sfmode == MCAST_EXCLUDE) { type = IGMPV3_CHANGE_TO_INCLUDE; skb = add_grec(skb, pmc, type, 1, 0); } pmc->crcount--; if (pmc->crcount == 0) { igmpv3_clear_zeros(&pmc->tomb); igmpv3_clear_zeros(&pmc->sources); } } if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) { if (pmc_prev) pmc_prev->next = pmc_next; else in_dev->mc_tomb = pmc_next; in_dev_put(pmc->interface); kfree_pmc(pmc); } else pmc_prev = pmc; } spin_unlock_bh(&in_dev->mc_tomb_lock); /* change recs */ for_each_pmc_rcu(in_dev, pmc) { spin_lock_bh(&pmc->lock); if (pmc->sfcount[MCAST_EXCLUDE]) { type = IGMPV3_BLOCK_OLD_SOURCES; dtype = IGMPV3_ALLOW_NEW_SOURCES; } else { type = IGMPV3_ALLOW_NEW_SOURCES; dtype = IGMPV3_BLOCK_OLD_SOURCES; } skb = add_grec(skb, pmc, type, 0, 0); skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */ /* filter mode changes */ if (pmc->crcount) { if (pmc->sfmode == MCAST_EXCLUDE) type = IGMPV3_CHANGE_TO_EXCLUDE; else type = IGMPV3_CHANGE_TO_INCLUDE; skb = add_grec(skb, pmc, type, 0, 0); pmc->crcount--; } spin_unlock_bh(&pmc->lock); } rcu_read_unlock(); if (!skb) return; (void) igmpv3_sendpack(skb); } static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc, int type) { struct sk_buff *skb; struct iphdr *iph; struct igmphdr *ih; struct rtable *rt; struct net_device *dev = in_dev->dev; struct net *net = dev_net(dev); __be32 group = pmc ? pmc->multiaddr : 0; struct flowi4 fl4; __be32 dst; int hlen, tlen; if (type == IGMPV3_HOST_MEMBERSHIP_REPORT) return igmpv3_send_report(in_dev, pmc); if (ipv4_is_local_multicast(group) && !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) return 0; if (type == IGMP_HOST_LEAVE_MESSAGE) dst = IGMP_ALL_ROUTER; else dst = group; rt = ip_route_output_ports(net, &fl4, NULL, dst, 0, 0, 0, IPPROTO_IGMP, 0, dev->ifindex); if (IS_ERR(rt)) return -1; hlen = LL_RESERVED_SPACE(dev); tlen = dev->needed_tailroom; skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC); if (!skb) { ip_rt_put(rt); return -1; } skb->priority = TC_PRIO_CONTROL; skb_dst_set(skb, &rt->dst); skb_reserve(skb, hlen); skb_reset_network_header(skb); iph = ip_hdr(skb); skb_put(skb, sizeof(struct iphdr) + 4); iph->version = 4; iph->ihl = (sizeof(struct iphdr)+4)>>2; iph->tos = 0xc0; iph->frag_off = htons(IP_DF); iph->ttl = 1; iph->daddr = dst; iph->saddr = fl4.saddr; iph->protocol = IPPROTO_IGMP; ip_select_ident(net, skb, NULL); ((u8 *)&iph[1])[0] = IPOPT_RA; ((u8 *)&iph[1])[1] = 4; ((u8 *)&iph[1])[2] = 0; ((u8 *)&iph[1])[3] = 0; ih = skb_put(skb, sizeof(struct igmphdr)); ih->type = type; ih->code = 0; ih->csum = 0; ih->group = group; ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr)); return ip_local_out(net, skb->sk, skb); } static void igmp_gq_timer_expire(struct timer_list *t) { struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer); in_dev->mr_gq_running = 0; igmpv3_send_report(in_dev, NULL); in_dev_put(in_dev); } static void igmp_ifc_timer_expire(struct timer_list *t) { struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer); u32 mr_ifc_count; igmpv3_send_cr(in_dev); restart: mr_ifc_count = READ_ONCE(in_dev->mr_ifc_count); if (mr_ifc_count) { if (cmpxchg(&in_dev->mr_ifc_count, mr_ifc_count, mr_ifc_count - 1) != mr_ifc_count) goto restart; igmp_ifc_start_timer(in_dev, unsolicited_report_interval(in_dev)); } in_dev_put(in_dev); } static void igmp_ifc_event(struct in_device *in_dev) { struct net *net = dev_net(in_dev->dev); if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) return; WRITE_ONCE(in_dev->mr_ifc_count, in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv)); igmp_ifc_start_timer(in_dev, 1); } static void igmp_timer_expire(struct timer_list *t) { struct ip_mc_list *im = from_timer(im, t, timer); struct in_device *in_dev = im->interface; spin_lock(&im->lock); im->tm_running = 0; if (im->unsolicit_count && --im->unsolicit_count) igmp_start_timer(im, unsolicited_report_interval(in_dev)); im->reporter = 1; spin_unlock(&im->lock); if (IGMP_V1_SEEN(in_dev)) igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT); else if (IGMP_V2_SEEN(in_dev)) igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT); else igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT); ip_ma_put(im); } /* mark EXCLUDE-mode sources */ static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) { struct ip_sf_list *psf; int i, scount; scount = 0; for (psf = pmc->sources; psf; psf = psf->sf_next) { if (scount == nsrcs) break; for (i = 0; i < nsrcs; i++) { /* skip inactive filters */ if (psf->sf_count[MCAST_INCLUDE] || pmc->sfcount[MCAST_EXCLUDE] != psf->sf_count[MCAST_EXCLUDE]) break; if (srcs[i] == psf->sf_inaddr) { scount++; break; } } } pmc->gsquery = 0; if (scount == nsrcs) /* all sources excluded */ return 0; return 1; } static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) { struct ip_sf_list *psf; int i, scount; if (pmc->sfmode == MCAST_EXCLUDE) return igmp_xmarksources(pmc, nsrcs, srcs); /* mark INCLUDE-mode sources */ scount = 0; for (psf = pmc->sources; psf; psf = psf->sf_next) { if (scount == nsrcs) break; for (i = 0; i < nsrcs; i++) if (srcs[i] == psf->sf_inaddr) { psf->sf_gsresp = 1; scount++; break; } } if (!scount) { pmc->gsquery = 0; return 0; } pmc->gsquery = 1; return 1; } /* return true if packet was dropped */ static bool igmp_heard_report(struct in_device *in_dev, __be32 group) { struct ip_mc_list *im; struct net *net = dev_net(in_dev->dev); /* Timers are only set for non-local groups */ if (group == IGMP_ALL_HOSTS) return false; if (ipv4_is_local_multicast(group) && !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) return false; rcu_read_lock(); for_each_pmc_rcu(in_dev, im) { if (im->multiaddr == group) { igmp_stop_timer(im); break; } } rcu_read_unlock(); return false; } /* return true if packet was dropped */ static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb, int len) { struct igmphdr *ih = igmp_hdr(skb); struct igmpv3_query *ih3 = igmpv3_query_hdr(skb); struct ip_mc_list *im; __be32 group = ih->group; int max_delay; int mark = 0; struct net *net = dev_net(in_dev->dev); if (len == 8) { if (ih->code == 0) { /* Alas, old v1 router presents here. */ max_delay = IGMP_QUERY_RESPONSE_INTERVAL; in_dev->mr_v1_seen = jiffies + (in_dev->mr_qrv * in_dev->mr_qi) + in_dev->mr_qri; group = 0; } else { /* v2 router present */ max_delay = ih->code*(HZ/IGMP_TIMER_SCALE); in_dev->mr_v2_seen = jiffies + (in_dev->mr_qrv * in_dev->mr_qi) + in_dev->mr_qri; } /* cancel the interface change timer */ WRITE_ONCE(in_dev->mr_ifc_count, 0); if (del_timer(&in_dev->mr_ifc_timer)) __in_dev_put(in_dev); /* clear deleted report items */ igmpv3_clear_delrec(in_dev); } else if (len < 12) { return true; /* ignore bogus packet; freed by caller */ } else if (IGMP_V1_SEEN(in_dev)) { /* This is a v3 query with v1 queriers present */ max_delay = IGMP_QUERY_RESPONSE_INTERVAL; group = 0; } else if (IGMP_V2_SEEN(in_dev)) { /* this is a v3 query with v2 queriers present; * Interpretation of the max_delay code is problematic here. * A real v2 host would use ih_code directly, while v3 has a * different encoding. We use the v3 encoding as more likely * to be intended in a v3 query. */ max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); if (!max_delay) max_delay = 1; /* can't mod w/ 0 */ } else { /* v3 */ if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) return true; ih3 = igmpv3_query_hdr(skb); if (ih3->nsrcs) { if (!pskb_may_pull(skb, sizeof(struct igmpv3_query) + ntohs(ih3->nsrcs)*sizeof(__be32))) return true; ih3 = igmpv3_query_hdr(skb); } max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); if (!max_delay) max_delay = 1; /* can't mod w/ 0 */ in_dev->mr_maxdelay = max_delay; /* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently * received value was zero, use the default or statically * configured value. */ in_dev->mr_qrv = ih3->qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL; /* RFC3376, 8.3. Query Response Interval: * The number of seconds represented by the [Query Response * Interval] must be less than the [Query Interval]. */ if (in_dev->mr_qri >= in_dev->mr_qi) in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ; if (!group) { /* general query */ if (ih3->nsrcs) return true; /* no sources allowed */ igmp_gq_start_timer(in_dev); return false; } /* mark sources to include, if group & source-specific */ mark = ih3->nsrcs != 0; } /* * - Start the timers in all of our membership records * that the query applies to for the interface on * which the query arrived excl. those that belong * to a "local" group (224.0.0.X) * - For timers already running check if they need to * be reset. * - Use the igmp->igmp_code field as the maximum * delay possible */ rcu_read_lock(); for_each_pmc_rcu(in_dev, im) { int changed; if (group && group != im->multiaddr) continue; if (im->multiaddr == IGMP_ALL_HOSTS) continue; if (ipv4_is_local_multicast(im->multiaddr) && !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) continue; spin_lock_bh(&im->lock); if (im->tm_running) im->gsquery = im->gsquery && mark; else im->gsquery = mark; changed = !im->gsquery || igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs); spin_unlock_bh(&im->lock); if (changed) igmp_mod_timer(im, max_delay); } rcu_read_unlock(); return false; } /* called in rcu_read_lock() section */ int igmp_rcv(struct sk_buff *skb) { /* This basically follows the spec line by line -- see RFC1112 */ struct igmphdr *ih; struct net_device *dev = skb->dev; struct in_device *in_dev; int len = skb->len; bool dropped = true; if (netif_is_l3_master(dev)) { dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif); if (!dev) goto drop; } in_dev = __in_dev_get_rcu(dev); if (!in_dev) goto drop; if (!pskb_may_pull(skb, sizeof(struct igmphdr))) goto drop; if (skb_checksum_simple_validate(skb)) goto drop; ih = igmp_hdr(skb); switch (ih->type) { case IGMP_HOST_MEMBERSHIP_QUERY: dropped = igmp_heard_query(in_dev, skb, len); break; case IGMP_HOST_MEMBERSHIP_REPORT: case IGMPV2_HOST_MEMBERSHIP_REPORT: /* Is it our report looped back? */ if (rt_is_output_route(skb_rtable(skb))) break; /* don't rely on MC router hearing unicast reports */ if (skb->pkt_type == PACKET_MULTICAST || skb->pkt_type == PACKET_BROADCAST) dropped = igmp_heard_report(in_dev, ih->group); break; case IGMP_PIM: #ifdef CONFIG_IP_PIMSM_V1 return pim_rcv_v1(skb); #endif case IGMPV3_HOST_MEMBERSHIP_REPORT: case IGMP_DVMRP: case IGMP_TRACE: case IGMP_HOST_LEAVE_MESSAGE: case IGMP_MTRACE: case IGMP_MTRACE_RESP: break; default: break; } drop: if (dropped) kfree_skb(skb); else consume_skb(skb); return 0; } #endif /* * Add a filter to a device */ static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr) { char buf[MAX_ADDR_LEN]; struct net_device *dev = in_dev->dev; /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG. We will get multicast token leakage, when IFF_MULTICAST is changed. This check should be done in ndo_set_rx_mode routine. Something sort of: if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; } --ANK */ if (arp_mc_map(addr, buf, dev, 0) == 0) dev_mc_add(dev, buf); } /* * Remove a filter from a device */ static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr) { char buf[MAX_ADDR_LEN]; struct net_device *dev = in_dev->dev; if (arp_mc_map(addr, buf, dev, 0) == 0) dev_mc_del(dev, buf); } #ifdef CONFIG_IP_MULTICAST /* * deleted ip_mc_list manipulation */ static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im, gfp_t gfp) { struct ip_mc_list *pmc; struct net *net = dev_net(in_dev->dev); /* this is an "ip_mc_list" for convenience; only the fields below * are actually used. In particular, the refcnt and users are not * used for management of the delete list. Using the same structure * for deleted items allows change reports to use common code with * non-deleted or query-response MCA's. */ pmc = kzalloc(sizeof(*pmc), gfp); if (!pmc) return; spin_lock_init(&pmc->lock); spin_lock_bh(&im->lock); pmc->interface = im->interface; in_dev_hold(in_dev); pmc->multiaddr = im->multiaddr; pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); pmc->sfmode = im->sfmode; if (pmc->sfmode == MCAST_INCLUDE) { struct ip_sf_list *psf; pmc->tomb = im->tomb; pmc->sources = im->sources; im->tomb = im->sources = NULL; for (psf = pmc->sources; psf; psf = psf->sf_next) psf->sf_crcount = pmc->crcount; } spin_unlock_bh(&im->lock); spin_lock_bh(&in_dev->mc_tomb_lock); pmc->next = in_dev->mc_tomb; in_dev->mc_tomb = pmc; spin_unlock_bh(&in_dev->mc_tomb_lock); } /* * restore ip_mc_list deleted records */ static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im) { struct ip_mc_list *pmc, *pmc_prev; struct ip_sf_list *psf; struct net *net = dev_net(in_dev->dev); __be32 multiaddr = im->multiaddr; spin_lock_bh(&in_dev->mc_tomb_lock); pmc_prev = NULL; for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) { if (pmc->multiaddr == multiaddr) break; pmc_prev = pmc; } if (pmc) { if (pmc_prev) pmc_prev->next = pmc->next; else in_dev->mc_tomb = pmc->next; } spin_unlock_bh(&in_dev->mc_tomb_lock); spin_lock_bh(&im->lock); if (pmc) { im->interface = pmc->interface; if (im->sfmode == MCAST_INCLUDE) { swap(im->tomb, pmc->tomb); swap(im->sources, pmc->sources); for (psf = im->sources; psf; psf = psf->sf_next) psf->sf_crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); } else { im->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); } in_dev_put(pmc->interface); kfree_pmc(pmc); } spin_unlock_bh(&im->lock); } /* * flush ip_mc_list deleted records */ static void igmpv3_clear_delrec(struct in_device *in_dev) { struct ip_mc_list *pmc, *nextpmc; spin_lock_bh(&in_dev->mc_tomb_lock); pmc = in_dev->mc_tomb; in_dev->mc_tomb = NULL; spin_unlock_bh(&in_dev->mc_tomb_lock); for (; pmc; pmc = nextpmc) { nextpmc = pmc->next; ip_mc_clear_src(pmc); in_dev_put(pmc->interface); kfree_pmc(pmc); } /* clear dead sources, too */ rcu_read_lock(); for_each_pmc_rcu(in_dev, pmc) { struct ip_sf_list *psf; spin_lock_bh(&pmc->lock); psf = pmc->tomb; pmc->tomb = NULL; spin_unlock_bh(&pmc->lock); ip_sf_list_clear_all(psf); } rcu_read_unlock(); } #endif static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp) { struct in_device *in_dev = im->interface; #ifdef CONFIG_IP_MULTICAST struct net *net = dev_net(in_dev->dev); int reporter; #endif if (im->loaded) { im->loaded = 0; ip_mc_filter_del(in_dev, im->multiaddr); } #ifdef CONFIG_IP_MULTICAST if (im->multiaddr == IGMP_ALL_HOSTS) return; if (ipv4_is_local_multicast(im->multiaddr) && !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) return; reporter = im->reporter; igmp_stop_timer(im); if (!in_dev->dead) { if (IGMP_V1_SEEN(in_dev)) return; if (IGMP_V2_SEEN(in_dev)) { if (reporter) igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE); return; } /* IGMPv3 */ igmpv3_add_delrec(in_dev, im, gfp); igmp_ifc_event(in_dev); } #endif } static void igmp_group_dropped(struct ip_mc_list *im) { __igmp_group_dropped(im, GFP_KERNEL); } static void igmp_group_added(struct ip_mc_list *im) { struct in_device *in_dev = im->interface; #ifdef CONFIG_IP_MULTICAST struct net *net = dev_net(in_dev->dev); #endif if (im->loaded == 0) { im->loaded = 1; ip_mc_filter_add(in_dev, im->multiaddr); } #ifdef CONFIG_IP_MULTICAST if (im->multiaddr == IGMP_ALL_HOSTS) return; if (ipv4_is_local_multicast(im->multiaddr) && !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) return; if (in_dev->dead) return; im->unsolicit_count = READ_ONCE(net->ipv4.sysctl_igmp_qrv); if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) { spin_lock_bh(&im->lock); igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY); spin_unlock_bh(&im->lock); return; } /* else, v3 */ /* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should * not send filter-mode change record as the mode should be from * IN() to IN(A). */ if (im->sfmode == MCAST_EXCLUDE) im->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); igmp_ifc_event(in_dev); #endif } /* * Multicast list managers */ static u32 ip_mc_hash(const struct ip_mc_list *im) { return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG); } static void ip_mc_hash_add(struct in_device *in_dev, struct ip_mc_list *im) { struct ip_mc_list __rcu **mc_hash; u32 hash; mc_hash = rtnl_dereference(in_dev->mc_hash); if (mc_hash) { hash = ip_mc_hash(im); im->next_hash = mc_hash[hash]; rcu_assign_pointer(mc_hash[hash], im); return; } /* do not use a hash table for small number of items */ if (in_dev->mc_count < 4) return; mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG, GFP_KERNEL); if (!mc_hash) return; for_each_pmc_rtnl(in_dev, im) { hash = ip_mc_hash(im); im->next_hash = mc_hash[hash]; RCU_INIT_POINTER(mc_hash[hash], im); } rcu_assign_pointer(in_dev->mc_hash, mc_hash); } static void ip_mc_hash_remove(struct in_device *in_dev, struct ip_mc_list *im) { struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash); struct ip_mc_list *aux; if (!mc_hash) return; mc_hash += ip_mc_hash(im); while ((aux = rtnl_dereference(*mc_hash)) != im) mc_hash = &aux->next_hash; *mc_hash = im->next_hash; } /* * A socket has joined a multicast group on device dev. */ static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr, unsigned int mode, gfp_t gfp) { struct ip_mc_list *im; ASSERT_RTNL(); for_each_pmc_rtnl(in_dev, im) { if (im->multiaddr == addr) { im->users++; ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0); goto out; } } im = kzalloc(sizeof(*im), gfp); if (!im) goto out; im->users = 1; im->interface = in_dev; in_dev_hold(in_dev); im->multiaddr = addr; /* initial mode is (EX, empty) */ im->sfmode = mode; im->sfcount[mode] = 1; refcount_set(&im->refcnt, 1); spin_lock_init(&im->lock); #ifdef CONFIG_IP_MULTICAST timer_setup(&im->timer, igmp_timer_expire, 0); #endif im->next_rcu = in_dev->mc_list; in_dev->mc_count++; rcu_assign_pointer(in_dev->mc_list, im); ip_mc_hash_add(in_dev, im); #ifdef CONFIG_IP_MULTICAST igmpv3_del_delrec(in_dev, im); #endif igmp_group_added(im); if (!in_dev->dead) ip_rt_multicast_event(in_dev); out: return; } void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp) { ____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp); } EXPORT_SYMBOL(__ip_mc_inc_group); void ip_mc_inc_group(struct in_device *in_dev, __be32 addr) { __ip_mc_inc_group(in_dev, addr, GFP_KERNEL); } EXPORT_SYMBOL(ip_mc_inc_group); static int ip_mc_check_iphdr(struct sk_buff *skb) { const struct iphdr *iph; unsigned int len; unsigned int offset = skb_network_offset(skb) + sizeof(*iph); if (!pskb_may_pull(skb, offset)) return -EINVAL; iph = ip_hdr(skb); if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph)) return -EINVAL; offset += ip_hdrlen(skb) - sizeof(*iph); if (!pskb_may_pull(skb, offset)) return -EINVAL; iph = ip_hdr(skb); if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) return -EINVAL; len = skb_network_offset(skb) + ntohs(iph->tot_len); if (skb->len < len || len < offset) return -EINVAL; skb_set_transport_header(skb, offset); return 0; } static int ip_mc_check_igmp_reportv3(struct sk_buff *skb) { unsigned int len = skb_transport_offset(skb); len += sizeof(struct igmpv3_report); return ip_mc_may_pull(skb, len) ? 0 : -EINVAL; } static int ip_mc_check_igmp_query(struct sk_buff *skb) { unsigned int transport_len = ip_transport_len(skb); unsigned int len; /* IGMPv{1,2}? */ if (transport_len != sizeof(struct igmphdr)) { /* or IGMPv3? */ if (transport_len < sizeof(struct igmpv3_query)) return -EINVAL; len = skb_transport_offset(skb) + sizeof(struct igmpv3_query); if (!ip_mc_may_pull(skb, len)) return -EINVAL; } /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer * all-systems destination addresses (224.0.0.1) for general queries */ if (!igmp_hdr(skb)->group && ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP)) return -EINVAL; return 0; } static int ip_mc_check_igmp_msg(struct sk_buff *skb) { switch (igmp_hdr(skb)->type) { case IGMP_HOST_LEAVE_MESSAGE: case IGMP_HOST_MEMBERSHIP_REPORT: case IGMPV2_HOST_MEMBERSHIP_REPORT: return 0; case IGMPV3_HOST_MEMBERSHIP_REPORT: return ip_mc_check_igmp_reportv3(skb); case IGMP_HOST_MEMBERSHIP_QUERY: return ip_mc_check_igmp_query(skb); default: return -ENOMSG; } } static __sum16 ip_mc_validate_checksum(struct sk_buff *skb) { return skb_checksum_simple_validate(skb); } static int ip_mc_check_igmp_csum(struct sk_buff *skb) { unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr); unsigned int transport_len = ip_transport_len(skb); struct sk_buff *skb_chk; if (!ip_mc_may_pull(skb, len)) return -EINVAL; skb_chk = skb_checksum_trimmed(skb, transport_len, ip_mc_validate_checksum); if (!skb_chk) return -EINVAL; if (skb_chk != skb) kfree_skb(skb_chk); return 0; } /** * ip_mc_check_igmp - checks whether this is a sane IGMP packet * @skb: the skb to validate * * Checks whether an IPv4 packet is a valid IGMP packet. If so sets * skb transport header accordingly and returns zero. * * -EINVAL: A broken packet was detected, i.e. it violates some internet * standard * -ENOMSG: IP header validation succeeded but it is not an IGMP packet. * -ENOMEM: A memory allocation failure happened. * * Caller needs to set the skb network header and free any returned skb if it * differs from the provided skb. */ int ip_mc_check_igmp(struct sk_buff *skb) { int ret = ip_mc_check_iphdr(skb); if (ret < 0) return ret; if (ip_hdr(skb)->protocol != IPPROTO_IGMP) return -ENOMSG; ret = ip_mc_check_igmp_csum(skb); if (ret < 0) return ret; return ip_mc_check_igmp_msg(skb); } EXPORT_SYMBOL(ip_mc_check_igmp); /* * Resend IGMP JOIN report; used by netdev notifier. */ static void ip_mc_rejoin_groups(struct in_device *in_dev) { #ifdef CONFIG_IP_MULTICAST struct ip_mc_list *im; int type; struct net *net = dev_net(in_dev->dev); ASSERT_RTNL(); for_each_pmc_rtnl(in_dev, im) { if (im->multiaddr == IGMP_ALL_HOSTS) continue; if (ipv4_is_local_multicast(im->multiaddr) && !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) continue; /* a failover is happening and switches * must be notified immediately */ if (IGMP_V1_SEEN(in_dev)) type = IGMP_HOST_MEMBERSHIP_REPORT; else if (IGMP_V2_SEEN(in_dev)) type = IGMPV2_HOST_MEMBERSHIP_REPORT; else type = IGMPV3_HOST_MEMBERSHIP_REPORT; igmp_send_report(in_dev, im, type); } #endif } /* * A socket has left a multicast group on device dev */ void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp) { struct ip_mc_list *i; struct ip_mc_list __rcu **ip; ASSERT_RTNL(); for (ip = &in_dev->mc_list; (i = rtnl_dereference(*ip)) != NULL; ip = &i->next_rcu) { if (i->multiaddr == addr) { if (--i->users == 0) { ip_mc_hash_remove(in_dev, i); *ip = i->next_rcu; in_dev->mc_count--; __igmp_group_dropped(i, gfp); ip_mc_clear_src(i); if (!in_dev->dead) ip_rt_multicast_event(in_dev); ip_ma_put(i); return; } break; } } } EXPORT_SYMBOL(__ip_mc_dec_group); /* Device changing type */ void ip_mc_unmap(struct in_device *in_dev) { struct ip_mc_list *pmc; ASSERT_RTNL(); for_each_pmc_rtnl(in_dev, pmc) igmp_group_dropped(pmc); } void ip_mc_remap(struct in_device *in_dev) { struct ip_mc_list *pmc; ASSERT_RTNL(); for_each_pmc_rtnl(in_dev, pmc) { #ifdef CONFIG_IP_MULTICAST igmpv3_del_delrec(in_dev, pmc); #endif igmp_group_added(pmc); } } /* Device going down */ void ip_mc_down(struct in_device *in_dev) { struct ip_mc_list *pmc; ASSERT_RTNL(); for_each_pmc_rtnl(in_dev, pmc) igmp_group_dropped(pmc); #ifdef CONFIG_IP_MULTICAST WRITE_ONCE(in_dev->mr_ifc_count, 0); if (del_timer(&in_dev->mr_ifc_timer)) __in_dev_put(in_dev); in_dev->mr_gq_running = 0; if (del_timer(&in_dev->mr_gq_timer)) __in_dev_put(in_dev); #endif ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS); } #ifdef CONFIG_IP_MULTICAST static void ip_mc_reset(struct in_device *in_dev) { struct net *net = dev_net(in_dev->dev); in_dev->mr_qi = IGMP_QUERY_INTERVAL; in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL; in_dev->mr_qrv = READ_ONCE(net->ipv4.sysctl_igmp_qrv); } #else static void ip_mc_reset(struct in_device *in_dev) { } #endif void ip_mc_init_dev(struct in_device *in_dev) { ASSERT_RTNL(); #ifdef CONFIG_IP_MULTICAST timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0); timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0); #endif ip_mc_reset(in_dev); spin_lock_init(&in_dev->mc_tomb_lock); } /* Device going up */ void ip_mc_up(struct in_device *in_dev) { struct ip_mc_list *pmc; ASSERT_RTNL(); ip_mc_reset(in_dev); ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS); for_each_pmc_rtnl(in_dev, pmc) { #ifdef CONFIG_IP_MULTICAST igmpv3_del_delrec(in_dev, pmc); #endif igmp_group_added(pmc); } } /* * Device is about to be destroyed: clean up. */ void ip_mc_destroy_dev(struct in_device *in_dev) { struct ip_mc_list *i; ASSERT_RTNL(); /* Deactivate timers */ ip_mc_down(in_dev); #ifdef CONFIG_IP_MULTICAST igmpv3_clear_delrec(in_dev); #endif while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) { in_dev->mc_list = i->next_rcu; in_dev->mc_count--; ip_mc_clear_src(i); ip_ma_put(i); } } /* RTNL is locked */ static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) { struct net_device *dev = NULL; struct in_device *idev = NULL; if (imr->imr_ifindex) { idev = inetdev_by_index(net, imr->imr_ifindex); return idev; } if (imr->imr_address.s_addr) { dev = __ip_dev_find(net, imr->imr_address.s_addr, false); if (!dev) return NULL; } if (!dev) { struct rtable *rt = ip_route_output(net, imr->imr_multiaddr.s_addr, 0, 0, 0); if (!IS_ERR(rt)) { dev = rt->dst.dev; ip_rt_put(rt); } } if (dev) { imr->imr_ifindex = dev->ifindex; idev = __in_dev_get_rtnl(dev); } return idev; } /* * Join a socket to a group */ static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode, __be32 *psfsrc) { struct ip_sf_list *psf, *psf_prev; int rv = 0; psf_prev = NULL; for (psf = pmc->sources; psf; psf = psf->sf_next) { if (psf->sf_inaddr == *psfsrc) break; psf_prev = psf; } if (!psf || psf->sf_count[sfmode] == 0) { /* source filter not found, or count wrong => bug */ return -ESRCH; } psf->sf_count[sfmode]--; if (psf->sf_count[sfmode] == 0) { ip_rt_multicast_event(pmc->interface); } if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) { #ifdef CONFIG_IP_MULTICAST struct in_device *in_dev = pmc->interface; struct net *net = dev_net(in_dev->dev); #endif /* no more filters for this source */ if (psf_prev) psf_prev->sf_next = psf->sf_next; else pmc->sources = psf->sf_next; #ifdef CONFIG_IP_MULTICAST if (psf->sf_oldin && !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) { psf->sf_crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); psf->sf_next = pmc->tomb; pmc->tomb = psf; rv = 1; } else #endif kfree(psf); } return rv; } #ifndef CONFIG_IP_MULTICAST #define igmp_ifc_event(x) do { } while (0) #endif static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode, int sfcount, __be32 *psfsrc, int delta) { struct ip_mc_list *pmc; int changerec = 0; int i, err; if (!in_dev) return -ENODEV; rcu_read_lock(); for_each_pmc_rcu(in_dev, pmc) { if (*pmca == pmc->multiaddr) break; } if (!pmc) { /* MCA not found?? bug */ rcu_read_unlock(); return -ESRCH; } spin_lock_bh(&pmc->lock); rcu_read_unlock(); #ifdef CONFIG_IP_MULTICAST sf_markstate(pmc); #endif if (!delta) { err = -EINVAL; if (!pmc->sfcount[sfmode]) goto out_unlock; pmc->sfcount[sfmode]--; } err = 0; for (i = 0; i < sfcount; i++) { int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]); changerec |= rv > 0; if (!err && rv < 0) err = rv; } if (pmc->sfmode == MCAST_EXCLUDE && pmc->sfcount[MCAST_EXCLUDE] == 0 && pmc->sfcount[MCAST_INCLUDE]) { #ifdef CONFIG_IP_MULTICAST struct ip_sf_list *psf; struct net *net = dev_net(in_dev->dev); #endif /* filter mode change */ pmc->sfmode = MCAST_INCLUDE; #ifdef CONFIG_IP_MULTICAST pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount); for (psf = pmc->sources; psf; psf = psf->sf_next) psf->sf_crcount = 0; igmp_ifc_event(pmc->interface); } else if (sf_setstate(pmc) || changerec) { igmp_ifc_event(pmc->interface); #endif } out_unlock: spin_unlock_bh(&pmc->lock); return err; } /* * Add multicast single-source filter to the interface list */ static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode, __be32 *psfsrc) { struct ip_sf_list *psf, *psf_prev; psf_prev = NULL; for (psf = pmc->sources; psf; psf = psf->sf_next) { if (psf->sf_inaddr == *psfsrc) break; psf_prev = psf; } if (!psf) { psf = kzalloc(sizeof(*psf), GFP_ATOMIC); if (!psf) return -ENOBUFS; psf->sf_inaddr = *psfsrc; if (psf_prev) { psf_prev->sf_next = psf; } else pmc->sources = psf; } psf->sf_count[sfmode]++; if (psf->sf_count[sfmode] == 1) { ip_rt_multicast_event(pmc->interface); } return 0; } #ifdef CONFIG_IP_MULTICAST static void sf_markstate(struct ip_mc_list *pmc) { struct ip_sf_list *psf; int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; for (psf = pmc->sources; psf; psf = psf->sf_next) if (pmc->sfcount[MCAST_EXCLUDE]) { psf->sf_oldin = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && !psf->sf_count[MCAST_INCLUDE]; } else psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0; } static int sf_setstate(struct ip_mc_list *pmc) { struct ip_sf_list *psf, *dpsf; int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; int qrv = pmc->interface->mr_qrv; int new_in, rv; rv = 0; for (psf = pmc->sources; psf; psf = psf->sf_next) { if (pmc->sfcount[MCAST_EXCLUDE]) { new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && !psf->sf_count[MCAST_INCLUDE]; } else new_in = psf->sf_count[MCAST_INCLUDE] != 0; if (new_in) { if (!psf->sf_oldin) { struct ip_sf_list *prev = NULL; for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) { if (dpsf->sf_inaddr == psf->sf_inaddr) break; prev = dpsf; } if (dpsf) { if (prev) prev->sf_next = dpsf->sf_next; else pmc->tomb = dpsf->sf_next; kfree(dpsf); } psf->sf_crcount = qrv; rv++; } } else if (psf->sf_oldin) { psf->sf_crcount = 0; /* * add or update "delete" records if an active filter * is now inactive */ for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) if (dpsf->sf_inaddr == psf->sf_inaddr) break; if (!dpsf) { dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC); if (!dpsf) continue; *dpsf = *psf; /* pmc->lock held by callers */ dpsf->sf_next = pmc->tomb; pmc->tomb = dpsf; } dpsf->sf_crcount = qrv; rv++; } } return rv; } #endif /* * Add multicast source filter list to the interface list */ static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, int sfcount, __be32 *psfsrc, int delta) { struct ip_mc_list *pmc; int isexclude; int i, err; if (!in_dev) return -ENODEV; rcu_read_lock(); for_each_pmc_rcu(in_dev, pmc) { if (*pmca == pmc->multiaddr) break; } if (!pmc) { /* MCA not found?? bug */ rcu_read_unlock(); return -ESRCH; } spin_lock_bh(&pmc->lock); rcu_read_unlock(); #ifdef CONFIG_IP_MULTICAST sf_markstate(pmc); #endif isexclude = pmc->sfmode == MCAST_EXCLUDE; if (!delta) pmc->sfcount[sfmode]++; err = 0; for (i = 0; i < sfcount; i++) { err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]); if (err) break; } if (err) { int j; if (!delta) pmc->sfcount[sfmode]--; for (j = 0; j < i; j++) (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]); } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) { #ifdef CONFIG_IP_MULTICAST struct ip_sf_list *psf; struct net *net = dev_net(pmc->interface->dev); in_dev = pmc->interface; #endif /* filter mode change */ if (pmc->sfcount[MCAST_EXCLUDE]) pmc->sfmode = MCAST_EXCLUDE; else if (pmc->sfcount[MCAST_INCLUDE]) pmc->sfmode = MCAST_INCLUDE; #ifdef CONFIG_IP_MULTICAST /* else no filters; keep old mode for reports */ pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount); for (psf = pmc->sources; psf; psf = psf->sf_next) psf->sf_crcount = 0; igmp_ifc_event(in_dev); } else if (sf_setstate(pmc)) { igmp_ifc_event(in_dev); #endif } spin_unlock_bh(&pmc->lock); return err; } static void ip_mc_clear_src(struct ip_mc_list *pmc) { struct ip_sf_list *tomb, *sources; spin_lock_bh(&pmc->lock); tomb = pmc->tomb; pmc->tomb = NULL; sources = pmc->sources; pmc->sources = NULL; pmc->sfmode = MCAST_EXCLUDE; pmc->sfcount[MCAST_INCLUDE] = 0; pmc->sfcount[MCAST_EXCLUDE] = 1; spin_unlock_bh(&pmc->lock); ip_sf_list_clear_all(tomb); ip_sf_list_clear_all(sources); } /* Join a multicast group */ static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr, unsigned int mode) { __be32 addr = imr->imr_multiaddr.s_addr; struct ip_mc_socklist *iml, *i; struct in_device *in_dev; struct inet_sock *inet = inet_sk(sk); struct net *net = sock_net(sk); int ifindex; int count = 0; int err; ASSERT_RTNL(); if (!ipv4_is_multicast(addr)) return -EINVAL; in_dev = ip_mc_find_dev(net, imr); if (!in_dev) { err = -ENODEV; goto done; } err = -EADDRINUSE; ifindex = imr->imr_ifindex; for_each_pmc_rtnl(inet, i) { if (i->multi.imr_multiaddr.s_addr == addr && i->multi.imr_ifindex == ifindex) goto done; count++; } err = -ENOBUFS; if (count >= READ_ONCE(net->ipv4.sysctl_igmp_max_memberships)) goto done; iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL); if (!iml) goto done; memcpy(&iml->multi, imr, sizeof(*imr)); iml->next_rcu = inet->mc_list; iml->sflist = NULL; iml->sfmode = mode; rcu_assign_pointer(inet->mc_list, iml); ____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL); err = 0; done: return err; } /* Join ASM (Any-Source Multicast) group */ int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr) { return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE); } EXPORT_SYMBOL(ip_mc_join_group); /* Join SSM (Source-Specific Multicast) group */ int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr, unsigned int mode) { return __ip_mc_join_group(sk, imr, mode); } static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml, struct in_device *in_dev) { struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist); int err; if (!psf) { /* any-source empty exclude case */ return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, iml->sfmode, 0, NULL, 0); } err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, iml->sfmode, psf->sl_count, psf->sl_addr, 0); RCU_INIT_POINTER(iml->sflist, NULL); /* decrease mem now to avoid the memleak warning */ atomic_sub(struct_size(psf, sl_addr, psf->sl_max), &sk->sk_omem_alloc); kfree_rcu(psf, rcu); return err; } int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr) { struct inet_sock *inet = inet_sk(sk); struct ip_mc_socklist *iml; struct ip_mc_socklist __rcu **imlp; struct in_device *in_dev; struct net *net = sock_net(sk); __be32 group = imr->imr_multiaddr.s_addr; u32 ifindex; int ret = -EADDRNOTAVAIL; ASSERT_RTNL(); in_dev = ip_mc_find_dev(net, imr); if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) { ret = -ENODEV; goto out; } ifindex = imr->imr_ifindex; for (imlp = &inet->mc_list; (iml = rtnl_dereference(*imlp)) != NULL; imlp = &iml->next_rcu) { if (iml->multi.imr_multiaddr.s_addr != group) continue; if (ifindex) { if (iml->multi.imr_ifindex != ifindex) continue; } else if (imr->imr_address.s_addr && imr->imr_address.s_addr != iml->multi.imr_address.s_addr) continue; (void) ip_mc_leave_src(sk, iml, in_dev); *imlp = iml->next_rcu; if (in_dev) ip_mc_dec_group(in_dev, group); /* decrease mem now to avoid the memleak warning */ atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); kfree_rcu(iml, rcu); return 0; } out: return ret; } EXPORT_SYMBOL(ip_mc_leave_group); int ip_mc_source(int add, int omode, struct sock *sk, struct ip_mreq_source *mreqs, int ifindex) { int err; struct ip_mreqn imr; __be32 addr = mreqs->imr_multiaddr; struct ip_mc_socklist *pmc; struct in_device *in_dev = NULL; struct inet_sock *inet = inet_sk(sk); struct ip_sf_socklist *psl; struct net *net = sock_net(sk); int leavegroup = 0; int i, j, rv; if (!ipv4_is_multicast(addr)) return -EINVAL; ASSERT_RTNL(); imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr; imr.imr_address.s_addr = mreqs->imr_interface; imr.imr_ifindex = ifindex; in_dev = ip_mc_find_dev(net, &imr); if (!in_dev) { err = -ENODEV; goto done; } err = -EADDRNOTAVAIL; for_each_pmc_rtnl(inet, pmc) { if ((pmc->multi.imr_multiaddr.s_addr == imr.imr_multiaddr.s_addr) && (pmc->multi.imr_ifindex == imr.imr_ifindex)) break; } if (!pmc) { /* must have a prior join */ err = -EINVAL; goto done; } /* if a source filter was set, must be the same mode as before */ if (pmc->sflist) { if (pmc->sfmode != omode) { err = -EINVAL; goto done; } } else if (pmc->sfmode != omode) { /* allow mode switches for empty-set filters */ ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0); ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0, NULL, 0); pmc->sfmode = omode; } psl = rtnl_dereference(pmc->sflist); if (!add) { if (!psl) goto done; /* err = -EADDRNOTAVAIL */ rv = !0; for (i = 0; i < psl->sl_count; i++) { rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, sizeof(__be32)); if (rv == 0) break; } if (rv) /* source not found */ goto done; /* err = -EADDRNOTAVAIL */ /* special case - (INCLUDE, empty) == LEAVE_GROUP */ if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { leavegroup = 1; goto done; } /* update the interface filter */ ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, &mreqs->imr_sourceaddr, 1); for (j = i+1; j < psl->sl_count; j++) psl->sl_addr[j-1] = psl->sl_addr[j]; psl->sl_count--; err = 0; goto done; } /* else, add a new source to the filter */ if (psl && psl->sl_count >= READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) { err = -ENOBUFS; goto done; } if (!psl || psl->sl_count == psl->sl_max) { struct ip_sf_socklist *newpsl; int count = IP_SFBLOCK; if (psl) count += psl->sl_max; newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count), GFP_KERNEL); if (!newpsl) { err = -ENOBUFS; goto done; } newpsl->sl_max = count; newpsl->sl_count = count - IP_SFBLOCK; if (psl) { for (i = 0; i < psl->sl_count; i++) newpsl->sl_addr[i] = psl->sl_addr[i]; /* decrease mem now to avoid the memleak warning */ atomic_sub(struct_size(psl, sl_addr, psl->sl_max), &sk->sk_omem_alloc); } rcu_assign_pointer(pmc->sflist, newpsl); if (psl) kfree_rcu(psl, rcu); psl = newpsl; } rv = 1; /* > 0 for insert logic below if sl_count is 0 */ for (i = 0; i < psl->sl_count; i++) { rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, sizeof(__be32)); if (rv == 0) break; } if (rv == 0) /* address already there is an error */ goto done; for (j = psl->sl_count-1; j >= i; j--) psl->sl_addr[j+1] = psl->sl_addr[j]; psl->sl_addr[i] = mreqs->imr_sourceaddr; psl->sl_count++; err = 0; /* update the interface list */ ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1, &mreqs->imr_sourceaddr, 1); done: if (leavegroup) err = ip_mc_leave_group(sk, &imr); return err; } int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex) { int err = 0; struct ip_mreqn imr; __be32 addr = msf->imsf_multiaddr; struct ip_mc_socklist *pmc; struct in_device *in_dev; struct inet_sock *inet = inet_sk(sk); struct ip_sf_socklist *newpsl, *psl; struct net *net = sock_net(sk); int leavegroup = 0; if (!ipv4_is_multicast(addr)) return -EINVAL; if (msf->imsf_fmode != MCAST_INCLUDE && msf->imsf_fmode != MCAST_EXCLUDE) return -EINVAL; ASSERT_RTNL(); imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; imr.imr_address.s_addr = msf->imsf_interface; imr.imr_ifindex = ifindex; in_dev = ip_mc_find_dev(net, &imr); if (!in_dev) { err = -ENODEV; goto done; } /* special case - (INCLUDE, empty) == LEAVE_GROUP */ if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) { leavegroup = 1; goto done; } for_each_pmc_rtnl(inet, pmc) { if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && pmc->multi.imr_ifindex == imr.imr_ifindex) break; } if (!pmc) { /* must have a prior join */ err = -EINVAL; goto done; } if (msf->imsf_numsrc) { newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, msf->imsf_numsrc), GFP_KERNEL); if (!newpsl) { err = -ENOBUFS; goto done; } newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc; memcpy(newpsl->sl_addr, msf->imsf_slist_flex, flex_array_size(msf, imsf_slist_flex, msf->imsf_numsrc)); err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr, msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0); if (err) { sock_kfree_s(sk, newpsl, struct_size(newpsl, sl_addr, newpsl->sl_max)); goto done; } } else { newpsl = NULL; (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr, msf->imsf_fmode, 0, NULL, 0); } psl = rtnl_dereference(pmc->sflist); if (psl) { (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, psl->sl_count, psl->sl_addr, 0); /* decrease mem now to avoid the memleak warning */ atomic_sub(struct_size(psl, sl_addr, psl->sl_max), &sk->sk_omem_alloc); } else { (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 0, NULL, 0); } rcu_assign_pointer(pmc->sflist, newpsl); if (psl) kfree_rcu(psl, rcu); pmc->sfmode = msf->imsf_fmode; err = 0; done: if (leavegroup) err = ip_mc_leave_group(sk, &imr); return err; } int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, sockptr_t optval, sockptr_t optlen) { int err, len, count, copycount, msf_size; struct ip_mreqn imr; __be32 addr = msf->imsf_multiaddr; struct ip_mc_socklist *pmc; struct in_device *in_dev; struct inet_sock *inet = inet_sk(sk); struct ip_sf_socklist *psl; struct net *net = sock_net(sk); ASSERT_RTNL(); if (!ipv4_is_multicast(addr)) return -EINVAL; imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; imr.imr_address.s_addr = msf->imsf_interface; imr.imr_ifindex = 0; in_dev = ip_mc_find_dev(net, &imr); if (!in_dev) { err = -ENODEV; goto done; } err = -EADDRNOTAVAIL; for_each_pmc_rtnl(inet, pmc) { if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && pmc->multi.imr_ifindex == imr.imr_ifindex) break; } if (!pmc) /* must have a prior join */ goto done; msf->imsf_fmode = pmc->sfmode; psl = rtnl_dereference(pmc->sflist); if (!psl) { count = 0; } else { count = psl->sl_count; } copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc; len = flex_array_size(psl, sl_addr, copycount); msf->imsf_numsrc = count; msf_size = IP_MSFILTER_SIZE(copycount); if (copy_to_sockptr(optlen, &msf_size, sizeof(int)) || copy_to_sockptr(optval, msf, IP_MSFILTER_SIZE(0))) { return -EFAULT; } if (len && copy_to_sockptr_offset(optval, offsetof(struct ip_msfilter, imsf_slist_flex), psl->sl_addr, len)) return -EFAULT; return 0; done: return err; } int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, sockptr_t optval, size_t ss_offset) { int i, count, copycount; struct sockaddr_in *psin; __be32 addr; struct ip_mc_socklist *pmc; struct inet_sock *inet = inet_sk(sk); struct ip_sf_socklist *psl; ASSERT_RTNL(); psin = (struct sockaddr_in *)&gsf->gf_group; if (psin->sin_family != AF_INET) return -EINVAL; addr = psin->sin_addr.s_addr; if (!ipv4_is_multicast(addr)) return -EINVAL; for_each_pmc_rtnl(inet, pmc) { if (pmc->multi.imr_multiaddr.s_addr == addr && pmc->multi.imr_ifindex == gsf->gf_interface) break; } if (!pmc) /* must have a prior join */ return -EADDRNOTAVAIL; gsf->gf_fmode = pmc->sfmode; psl = rtnl_dereference(pmc->sflist); count = psl ? psl->sl_count : 0; copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; gsf->gf_numsrc = count; for (i = 0; i < copycount; i++) { struct sockaddr_storage ss; psin = (struct sockaddr_in *)&ss; memset(&ss, 0, sizeof(ss)); psin->sin_family = AF_INET; psin->sin_addr.s_addr = psl->sl_addr[i]; if (copy_to_sockptr_offset(optval, ss_offset, &ss, sizeof(ss))) return -EFAULT; ss_offset += sizeof(ss); } return 0; } /* * check if a multicast source filter allows delivery for a given <src,dst,intf> */ int ip_mc_sf_allow(const struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif, int sdif) { const struct inet_sock *inet = inet_sk(sk); struct ip_mc_socklist *pmc; struct ip_sf_socklist *psl; int i; int ret; ret = 1; if (!ipv4_is_multicast(loc_addr)) goto out; rcu_read_lock(); for_each_pmc_rcu(inet, pmc) { if (pmc->multi.imr_multiaddr.s_addr == loc_addr && (pmc->multi.imr_ifindex == dif || (sdif && pmc->multi.imr_ifindex == sdif))) break; } ret = inet_test_bit(MC_ALL, sk); if (!pmc) goto unlock; psl = rcu_dereference(pmc->sflist); ret = (pmc->sfmode == MCAST_EXCLUDE); if (!psl) goto unlock; for (i = 0; i < psl->sl_count; i++) { if (psl->sl_addr[i] == rmt_addr) break; } ret = 0; if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count) goto unlock; if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count) goto unlock; ret = 1; unlock: rcu_read_unlock(); out: return ret; } /* * A socket is closing. */ void ip_mc_drop_socket(struct sock *sk) { struct inet_sock *inet = inet_sk(sk); struct ip_mc_socklist *iml; struct net *net = sock_net(sk); if (!inet->mc_list) return; rtnl_lock(); while ((iml = rtnl_dereference(inet->mc_list)) != NULL) { struct in_device *in_dev; inet->mc_list = iml->next_rcu; in_dev = inetdev_by_index(net, iml->multi.imr_ifindex); (void) ip_mc_leave_src(sk, iml, in_dev); if (in_dev) ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr); /* decrease mem now to avoid the memleak warning */ atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); kfree_rcu(iml, rcu); } rtnl_unlock(); } /* called with rcu_read_lock() */ int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto) { struct ip_mc_list *im; struct ip_mc_list __rcu **mc_hash; struct ip_sf_list *psf; int rv = 0; mc_hash = rcu_dereference(in_dev->mc_hash); if (mc_hash) { u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG); for (im = rcu_dereference(mc_hash[hash]); im != NULL; im = rcu_dereference(im->next_hash)) { if (im->multiaddr == mc_addr) break; } } else { for_each_pmc_rcu(in_dev, im) { if (im->multiaddr == mc_addr) break; } } if (im && proto == IPPROTO_IGMP) { rv = 1; } else if (im) { if (src_addr) { spin_lock_bh(&im->lock); for (psf = im->sources; psf; psf = psf->sf_next) { if (psf->sf_inaddr == src_addr) break; } if (psf) rv = psf->sf_count[MCAST_INCLUDE] || psf->sf_count[MCAST_EXCLUDE] != im->sfcount[MCAST_EXCLUDE]; else rv = im->sfcount[MCAST_EXCLUDE] != 0; spin_unlock_bh(&im->lock); } else rv = 1; /* unspecified source; tentatively allow */ } return rv; } #if defined(CONFIG_PROC_FS) struct igmp_mc_iter_state { struct seq_net_private p; struct net_device *dev; struct in_device *in_dev; }; #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private) static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq) { struct net *net = seq_file_net(seq); struct ip_mc_list *im = NULL; struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); state->in_dev = NULL; for_each_netdev_rcu(net, state->dev) { struct in_device *in_dev; in_dev = __in_dev_get_rcu(state->dev); if (!in_dev) continue; im = rcu_dereference(in_dev->mc_list); if (im) { state->in_dev = in_dev; break; } } return im; } static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im) { struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); im = rcu_dereference(im->next_rcu); while (!im) { state->dev = next_net_device_rcu(state->dev); if (!state->dev) { state->in_dev = NULL; break; } state->in_dev = __in_dev_get_rcu(state->dev); if (!state->in_dev) continue; im = rcu_dereference(state->in_dev->mc_list); } return im; } static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos) { struct ip_mc_list *im = igmp_mc_get_first(seq); if (im) while (pos && (im = igmp_mc_get_next(seq, im)) != NULL) --pos; return pos ? NULL : im; } static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos) __acquires(rcu) { rcu_read_lock(); return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; } static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct ip_mc_list *im; if (v == SEQ_START_TOKEN) im = igmp_mc_get_first(seq); else im = igmp_mc_get_next(seq, v); ++*pos; return im; } static void igmp_mc_seq_stop(struct seq_file *seq, void *v) __releases(rcu) { struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); state->in_dev = NULL; state->dev = NULL; rcu_read_unlock(); } static int igmp_mc_seq_show(struct seq_file *seq, void *v) { if (v == SEQ_START_TOKEN) seq_puts(seq, "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n"); else { struct ip_mc_list *im = v; struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); char *querier; long delta; #ifdef CONFIG_IP_MULTICAST querier = IGMP_V1_SEEN(state->in_dev) ? "V1" : IGMP_V2_SEEN(state->in_dev) ? "V2" : "V3"; #else querier = "NONE"; #endif if (rcu_access_pointer(state->in_dev->mc_list) == im) { seq_printf(seq, "%d\t%-10s: %5d %7s\n", state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier); } delta = im->timer.expires - jiffies; seq_printf(seq, "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", im->multiaddr, im->users, im->tm_running, im->tm_running ? jiffies_delta_to_clock_t(delta) : 0, im->reporter); } return 0; } static const struct seq_operations igmp_mc_seq_ops = { .start = igmp_mc_seq_start, .next = igmp_mc_seq_next, .stop = igmp_mc_seq_stop, .show = igmp_mc_seq_show, }; struct igmp_mcf_iter_state { struct seq_net_private p; struct net_device *dev; struct in_device *idev; struct ip_mc_list *im; }; #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private) static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq) { struct net *net = seq_file_net(seq); struct ip_sf_list *psf = NULL; struct ip_mc_list *im = NULL; struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); state->idev = NULL; state->im = NULL; for_each_netdev_rcu(net, state->dev) { struct in_device *idev; idev = __in_dev_get_rcu(state->dev); if (unlikely(!idev)) continue; im = rcu_dereference(idev->mc_list); if (likely(im)) { spin_lock_bh(&im->lock); psf = im->sources; if (likely(psf)) { state->im = im; state->idev = idev; break; } spin_unlock_bh(&im->lock); } } return psf; } static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf) { struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); psf = psf->sf_next; while (!psf) { spin_unlock_bh(&state->im->lock); state->im = state->im->next; while (!state->im) { state->dev = next_net_device_rcu(state->dev); if (!state->dev) { state->idev = NULL; goto out; } state->idev = __in_dev_get_rcu(state->dev); if (!state->idev) continue; state->im = rcu_dereference(state->idev->mc_list); } if (!state->im) break; spin_lock_bh(&state->im->lock); psf = state->im->sources; } out: return psf; } static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos) { struct ip_sf_list *psf = igmp_mcf_get_first(seq); if (psf) while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL) --pos; return pos ? NULL : psf; } static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos) __acquires(rcu) { rcu_read_lock(); return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; } static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct ip_sf_list *psf; if (v == SEQ_START_TOKEN) psf = igmp_mcf_get_first(seq); else psf = igmp_mcf_get_next(seq, v); ++*pos; return psf; } static void igmp_mcf_seq_stop(struct seq_file *seq, void *v) __releases(rcu) { struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); if (likely(state->im)) { spin_unlock_bh(&state->im->lock); state->im = NULL; } state->idev = NULL; state->dev = NULL; rcu_read_unlock(); } static int igmp_mcf_seq_show(struct seq_file *seq, void *v) { struct ip_sf_list *psf = v; struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); if (v == SEQ_START_TOKEN) { seq_puts(seq, "Idx Device MCA SRC INC EXC\n"); } else { seq_printf(seq, "%3d %6.6s 0x%08x " "0x%08x %6lu %6lu\n", state->dev->ifindex, state->dev->name, ntohl(state->im->multiaddr), ntohl(psf->sf_inaddr), psf->sf_count[MCAST_INCLUDE], psf->sf_count[MCAST_EXCLUDE]); } return 0; } static const struct seq_operations igmp_mcf_seq_ops = { .start = igmp_mcf_seq_start, .next = igmp_mcf_seq_next, .stop = igmp_mcf_seq_stop, .show = igmp_mcf_seq_show, }; static int __net_init igmp_net_init(struct net *net) { struct proc_dir_entry *pde; int err; pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops, sizeof(struct igmp_mc_iter_state)); if (!pde) goto out_igmp; pde = proc_create_net("mcfilter", 0444, net->proc_net, &igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state)); if (!pde) goto out_mcfilter; err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET, SOCK_DGRAM, 0, net); if (err < 0) { pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n", err); goto out_sock; } return 0; out_sock: remove_proc_entry("mcfilter", net->proc_net); out_mcfilter: remove_proc_entry("igmp", net->proc_net); out_igmp: return -ENOMEM; } static void __net_exit igmp_net_exit(struct net *net) { remove_proc_entry("mcfilter", net->proc_net); remove_proc_entry("igmp", net->proc_net); inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk); } static struct pernet_operations igmp_net_ops = { .init = igmp_net_init, .exit = igmp_net_exit, }; #endif static int igmp_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct in_device *in_dev; switch (event) { case NETDEV_RESEND_IGMP: in_dev = __in_dev_get_rtnl(dev); if (in_dev) ip_mc_rejoin_groups(in_dev); break; default: break; } return NOTIFY_DONE; } static struct notifier_block igmp_notifier = { .notifier_call = igmp_netdev_event, }; int __init igmp_mc_init(void) { #if defined(CONFIG_PROC_FS) int err; err = register_pernet_subsys(&igmp_net_ops); if (err) return err; err = register_netdevice_notifier(&igmp_notifier); if (err) goto reg_notif_fail; return 0; reg_notif_fail: unregister_pernet_subsys(&igmp_net_ops); return err; #else return register_netdevice_notifier(&igmp_notifier); #endif }
linux-master
net/ipv4/igmp.c
// SPDX-License-Identifier: GPL-2.0-only /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Generic TIME_WAIT sockets functions * * From code orinally in TCP */ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/module.h> #include <net/inet_hashtables.h> #include <net/inet_timewait_sock.h> #include <net/ip.h> /** * inet_twsk_bind_unhash - unhash a timewait socket from bind hash * @tw: timewait socket * @hashinfo: hashinfo pointer * * unhash a timewait socket from bind hash, if hashed. * bind hash lock must be held by caller. * Returns 1 if caller should call inet_twsk_put() after lock release. */ void inet_twsk_bind_unhash(struct inet_timewait_sock *tw, struct inet_hashinfo *hashinfo) { struct inet_bind2_bucket *tb2 = tw->tw_tb2; struct inet_bind_bucket *tb = tw->tw_tb; if (!tb) return; __hlist_del(&tw->tw_bind_node); tw->tw_tb = NULL; inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb); __hlist_del(&tw->tw_bind2_node); tw->tw_tb2 = NULL; inet_bind2_bucket_destroy(hashinfo->bind2_bucket_cachep, tb2); __sock_put((struct sock *)tw); } /* Must be called with locally disabled BHs. */ static void inet_twsk_kill(struct inet_timewait_sock *tw) { struct inet_hashinfo *hashinfo = tw->tw_dr->hashinfo; spinlock_t *lock = inet_ehash_lockp(hashinfo, tw->tw_hash); struct inet_bind_hashbucket *bhead, *bhead2; spin_lock(lock); sk_nulls_del_node_init_rcu((struct sock *)tw); spin_unlock(lock); /* Disassociate with bind bucket. */ bhead = &hashinfo->bhash[inet_bhashfn(twsk_net(tw), tw->tw_num, hashinfo->bhash_size)]; bhead2 = inet_bhashfn_portaddr(hashinfo, (struct sock *)tw, twsk_net(tw), tw->tw_num); spin_lock(&bhead->lock); spin_lock(&bhead2->lock); inet_twsk_bind_unhash(tw, hashinfo); spin_unlock(&bhead2->lock); spin_unlock(&bhead->lock); refcount_dec(&tw->tw_dr->tw_refcount); inet_twsk_put(tw); } void inet_twsk_free(struct inet_timewait_sock *tw) { struct module *owner = tw->tw_prot->owner; twsk_destructor((struct sock *)tw); kmem_cache_free(tw->tw_prot->twsk_prot->twsk_slab, tw); module_put(owner); } void inet_twsk_put(struct inet_timewait_sock *tw) { if (refcount_dec_and_test(&tw->tw_refcnt)) inet_twsk_free(tw); } EXPORT_SYMBOL_GPL(inet_twsk_put); static void inet_twsk_add_node_rcu(struct inet_timewait_sock *tw, struct hlist_nulls_head *list) { hlist_nulls_add_head_rcu(&tw->tw_node, list); } static void inet_twsk_add_bind_node(struct inet_timewait_sock *tw, struct hlist_head *list) { hlist_add_head(&tw->tw_bind_node, list); } static void inet_twsk_add_bind2_node(struct inet_timewait_sock *tw, struct hlist_head *list) { hlist_add_head(&tw->tw_bind2_node, list); } /* * Enter the time wait state. This is called with locally disabled BH. * Essentially we whip up a timewait bucket, copy the relevant info into it * from the SK, and mess with hash chains and list linkage. */ void inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk, struct inet_hashinfo *hashinfo) { const struct inet_sock *inet = inet_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); struct inet_ehash_bucket *ehead = inet_ehash_bucket(hashinfo, sk->sk_hash); spinlock_t *lock = inet_ehash_lockp(hashinfo, sk->sk_hash); struct inet_bind_hashbucket *bhead, *bhead2; /* Step 1: Put TW into bind hash. Original socket stays there too. Note, that any socket with inet->num != 0 MUST be bound in binding cache, even if it is closed. */ bhead = &hashinfo->bhash[inet_bhashfn(twsk_net(tw), inet->inet_num, hashinfo->bhash_size)]; bhead2 = inet_bhashfn_portaddr(hashinfo, sk, twsk_net(tw), inet->inet_num); spin_lock(&bhead->lock); spin_lock(&bhead2->lock); tw->tw_tb = icsk->icsk_bind_hash; WARN_ON(!icsk->icsk_bind_hash); inet_twsk_add_bind_node(tw, &tw->tw_tb->owners); tw->tw_tb2 = icsk->icsk_bind2_hash; WARN_ON(!icsk->icsk_bind2_hash); inet_twsk_add_bind2_node(tw, &tw->tw_tb2->deathrow); spin_unlock(&bhead2->lock); spin_unlock(&bhead->lock); spin_lock(lock); inet_twsk_add_node_rcu(tw, &ehead->chain); /* Step 3: Remove SK from hash chain */ if (__sk_nulls_del_node_init_rcu(sk)) sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); spin_unlock(lock); /* tw_refcnt is set to 3 because we have : * - one reference for bhash chain. * - one reference for ehash chain. * - one reference for timer. * We can use atomic_set() because prior spin_lock()/spin_unlock() * committed into memory all tw fields. * Also note that after this point, we lost our implicit reference * so we are not allowed to use tw anymore. */ refcount_set(&tw->tw_refcnt, 3); } EXPORT_SYMBOL_GPL(inet_twsk_hashdance); static void tw_timer_handler(struct timer_list *t) { struct inet_timewait_sock *tw = from_timer(tw, t, tw_timer); inet_twsk_kill(tw); } struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk, struct inet_timewait_death_row *dr, const int state) { struct inet_timewait_sock *tw; if (refcount_read(&dr->tw_refcount) - 1 >= READ_ONCE(dr->sysctl_max_tw_buckets)) return NULL; tw = kmem_cache_alloc(sk->sk_prot_creator->twsk_prot->twsk_slab, GFP_ATOMIC); if (tw) { const struct inet_sock *inet = inet_sk(sk); tw->tw_dr = dr; /* Give us an identity. */ tw->tw_daddr = inet->inet_daddr; tw->tw_rcv_saddr = inet->inet_rcv_saddr; tw->tw_bound_dev_if = sk->sk_bound_dev_if; tw->tw_tos = inet->tos; tw->tw_num = inet->inet_num; tw->tw_state = TCP_TIME_WAIT; tw->tw_substate = state; tw->tw_sport = inet->inet_sport; tw->tw_dport = inet->inet_dport; tw->tw_family = sk->sk_family; tw->tw_reuse = sk->sk_reuse; tw->tw_reuseport = sk->sk_reuseport; tw->tw_hash = sk->sk_hash; tw->tw_ipv6only = 0; tw->tw_transparent = inet_test_bit(TRANSPARENT, sk); tw->tw_prot = sk->sk_prot_creator; atomic64_set(&tw->tw_cookie, atomic64_read(&sk->sk_cookie)); twsk_net_set(tw, sock_net(sk)); timer_setup(&tw->tw_timer, tw_timer_handler, TIMER_PINNED); /* * Because we use RCU lookups, we should not set tw_refcnt * to a non null value before everything is setup for this * timewait socket. */ refcount_set(&tw->tw_refcnt, 0); __module_get(tw->tw_prot->owner); } return tw; } EXPORT_SYMBOL_GPL(inet_twsk_alloc); /* These are always called from BH context. See callers in * tcp_input.c to verify this. */ /* This is for handling early-kills of TIME_WAIT sockets. * Warning : consume reference. * Caller should not access tw anymore. */ void inet_twsk_deschedule_put(struct inet_timewait_sock *tw) { if (del_timer_sync(&tw->tw_timer)) inet_twsk_kill(tw); inet_twsk_put(tw); } EXPORT_SYMBOL(inet_twsk_deschedule_put); void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo, bool rearm) { /* timeout := RTO * 3.5 * * 3.5 = 1+2+0.5 to wait for two retransmits. * * RATIONALE: if FIN arrived and we entered TIME-WAIT state, * our ACK acking that FIN can be lost. If N subsequent retransmitted * FINs (or previous seqments) are lost (probability of such event * is p^(N+1), where p is probability to lose single packet and * time to detect the loss is about RTO*(2^N - 1) with exponential * backoff). Normal timewait length is calculated so, that we * waited at least for one retransmitted FIN (maximal RTO is 120sec). * [ BTW Linux. following BSD, violates this requirement waiting * only for 60sec, we should wait at least for 240 secs. * Well, 240 consumes too much of resources 8) * ] * This interval is not reduced to catch old duplicate and * responces to our wandering segments living for two MSLs. * However, if we use PAWS to detect * old duplicates, we can reduce the interval to bounds required * by RTO, rather than MSL. So, if peer understands PAWS, we * kill tw bucket after 3.5*RTO (it is important that this number * is greater than TS tick!) and detect old duplicates with help * of PAWS. */ if (!rearm) { bool kill = timeo <= 4*HZ; __NET_INC_STATS(twsk_net(tw), kill ? LINUX_MIB_TIMEWAITKILLED : LINUX_MIB_TIMEWAITED); BUG_ON(mod_timer(&tw->tw_timer, jiffies + timeo)); refcount_inc(&tw->tw_dr->tw_refcount); } else { mod_timer_pending(&tw->tw_timer, jiffies + timeo); } } EXPORT_SYMBOL_GPL(__inet_twsk_schedule); void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family) { struct inet_timewait_sock *tw; struct sock *sk; struct hlist_nulls_node *node; unsigned int slot; for (slot = 0; slot <= hashinfo->ehash_mask; slot++) { struct inet_ehash_bucket *head = &hashinfo->ehash[slot]; restart_rcu: cond_resched(); rcu_read_lock(); restart: sk_nulls_for_each_rcu(sk, node, &head->chain) { if (sk->sk_state != TCP_TIME_WAIT) { /* A kernel listener socket might not hold refcnt for net, * so reqsk_timer_handler() could be fired after net is * freed. Userspace listener and reqsk never exist here. */ if (unlikely(sk->sk_state == TCP_NEW_SYN_RECV && hashinfo->pernet)) { struct request_sock *req = inet_reqsk(sk); inet_csk_reqsk_queue_drop_and_put(req->rsk_listener, req); } continue; } tw = inet_twsk(sk); if ((tw->tw_family != family) || refcount_read(&twsk_net(tw)->ns.count)) continue; if (unlikely(!refcount_inc_not_zero(&tw->tw_refcnt))) continue; if (unlikely((tw->tw_family != family) || refcount_read(&twsk_net(tw)->ns.count))) { inet_twsk_put(tw); goto restart; } rcu_read_unlock(); local_bh_disable(); inet_twsk_deschedule_put(tw); local_bh_enable(); goto restart_rcu; } /* If the nulls value we got at the end of this lookup is * not the expected one, we must restart lookup. * We probably met an item that was moved to another chain. */ if (get_nulls_value(node) != slot) goto restart; rcu_read_unlock(); } } EXPORT_SYMBOL_GPL(inet_twsk_purge);
linux-master
net/ipv4/inet_timewait_sock.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Implementation of the Transmission Control Protocol(TCP). * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * Mark Evans, <[email protected]> * Corey Minyard <[email protected]> * Florian La Roche, <[email protected]> * Charles Hedrick, <[email protected]> * Linus Torvalds, <[email protected]> * Alan Cox, <[email protected]> * Matthew Dillon, <[email protected]> * Arnt Gulbrandsen, <[email protected]> * Jorge Cwik, <[email protected]> * * Fixes: * Alan Cox : Numerous verify_area() calls * Alan Cox : Set the ACK bit on a reset * Alan Cox : Stopped it crashing if it closed while * sk->inuse=1 and was trying to connect * (tcp_err()). * Alan Cox : All icmp error handling was broken * pointers passed where wrong and the * socket was looked up backwards. Nobody * tested any icmp error code obviously. * Alan Cox : tcp_err() now handled properly. It * wakes people on errors. poll * behaves and the icmp error race * has gone by moving it into sock.c * Alan Cox : tcp_send_reset() fixed to work for * everything not just packets for * unknown sockets. * Alan Cox : tcp option processing. * Alan Cox : Reset tweaked (still not 100%) [Had * syn rule wrong] * Herp Rosmanith : More reset fixes * Alan Cox : No longer acks invalid rst frames. * Acking any kind of RST is right out. * Alan Cox : Sets an ignore me flag on an rst * receive otherwise odd bits of prattle * escape still * Alan Cox : Fixed another acking RST frame bug. * Should stop LAN workplace lockups. * Alan Cox : Some tidyups using the new skb list * facilities * Alan Cox : sk->keepopen now seems to work * Alan Cox : Pulls options out correctly on accepts * Alan Cox : Fixed assorted sk->rqueue->next errors * Alan Cox : PSH doesn't end a TCP read. Switched a * bit to skb ops. * Alan Cox : Tidied tcp_data to avoid a potential * nasty. * Alan Cox : Added some better commenting, as the * tcp is hard to follow * Alan Cox : Removed incorrect check for 20 * psh * Michael O'Reilly : ack < copied bug fix. * Johannes Stille : Misc tcp fixes (not all in yet). * Alan Cox : FIN with no memory -> CRASH * Alan Cox : Added socket option proto entries. * Also added awareness of them to accept. * Alan Cox : Added TCP options (SOL_TCP) * Alan Cox : Switched wakeup calls to callbacks, * so the kernel can layer network * sockets. * Alan Cox : Use ip_tos/ip_ttl settings. * Alan Cox : Handle FIN (more) properly (we hope). * Alan Cox : RST frames sent on unsynchronised * state ack error. * Alan Cox : Put in missing check for SYN bit. * Alan Cox : Added tcp_select_window() aka NET2E * window non shrink trick. * Alan Cox : Added a couple of small NET2E timer * fixes * Charles Hedrick : TCP fixes * Toomas Tamm : TCP window fixes * Alan Cox : Small URG fix to rlogin ^C ack fight * Charles Hedrick : Rewrote most of it to actually work * Linus : Rewrote tcp_read() and URG handling * completely * Gerhard Koerting: Fixed some missing timer handling * Matthew Dillon : Reworked TCP machine states as per RFC * Gerhard Koerting: PC/TCP workarounds * Adam Caldwell : Assorted timer/timing errors * Matthew Dillon : Fixed another RST bug * Alan Cox : Move to kernel side addressing changes. * Alan Cox : Beginning work on TCP fastpathing * (not yet usable) * Arnt Gulbrandsen: Turbocharged tcp_check() routine. * Alan Cox : TCP fast path debugging * Alan Cox : Window clamping * Michael Riepe : Bug in tcp_check() * Matt Dillon : More TCP improvements and RST bug fixes * Matt Dillon : Yet more small nasties remove from the * TCP code (Be very nice to this man if * tcp finally works 100%) 8) * Alan Cox : BSD accept semantics. * Alan Cox : Reset on closedown bug. * Peter De Schrijver : ENOTCONN check missing in tcp_sendto(). * Michael Pall : Handle poll() after URG properly in * all cases. * Michael Pall : Undo the last fix in tcp_read_urg() * (multi URG PUSH broke rlogin). * Michael Pall : Fix the multi URG PUSH problem in * tcp_readable(), poll() after URG * works now. * Michael Pall : recv(...,MSG_OOB) never blocks in the * BSD api. * Alan Cox : Changed the semantics of sk->socket to * fix a race and a signal problem with * accept() and async I/O. * Alan Cox : Relaxed the rules on tcp_sendto(). * Yury Shevchuk : Really fixed accept() blocking problem. * Craig I. Hagan : Allow for BSD compatible TIME_WAIT for * clients/servers which listen in on * fixed ports. * Alan Cox : Cleaned the above up and shrank it to * a sensible code size. * Alan Cox : Self connect lockup fix. * Alan Cox : No connect to multicast. * Ross Biro : Close unaccepted children on master * socket close. * Alan Cox : Reset tracing code. * Alan Cox : Spurious resets on shutdown. * Alan Cox : Giant 15 minute/60 second timer error * Alan Cox : Small whoops in polling before an * accept. * Alan Cox : Kept the state trace facility since * it's handy for debugging. * Alan Cox : More reset handler fixes. * Alan Cox : Started rewriting the code based on * the RFC's for other useful protocol * references see: Comer, KA9Q NOS, and * for a reference on the difference * between specifications and how BSD * works see the 4.4lite source. * A.N.Kuznetsov : Don't time wait on completion of tidy * close. * Linus Torvalds : Fin/Shutdown & copied_seq changes. * Linus Torvalds : Fixed BSD port reuse to work first syn * Alan Cox : Reimplemented timers as per the RFC * and using multiple timers for sanity. * Alan Cox : Small bug fixes, and a lot of new * comments. * Alan Cox : Fixed dual reader crash by locking * the buffers (much like datagram.c) * Alan Cox : Fixed stuck sockets in probe. A probe * now gets fed up of retrying without * (even a no space) answer. * Alan Cox : Extracted closing code better * Alan Cox : Fixed the closing state machine to * resemble the RFC. * Alan Cox : More 'per spec' fixes. * Jorge Cwik : Even faster checksumming. * Alan Cox : tcp_data() doesn't ack illegal PSH * only frames. At least one pc tcp stack * generates them. * Alan Cox : Cache last socket. * Alan Cox : Per route irtt. * Matt Day : poll()->select() match BSD precisely on error * Alan Cox : New buffers * Marc Tamsky : Various sk->prot->retransmits and * sk->retransmits misupdating fixed. * Fixed tcp_write_timeout: stuck close, * and TCP syn retries gets used now. * Mark Yarvis : In tcp_read_wakeup(), don't send an * ack if state is TCP_CLOSED. * Alan Cox : Look up device on a retransmit - routes may * change. Doesn't yet cope with MSS shrink right * but it's a start! * Marc Tamsky : Closing in closing fixes. * Mike Shaver : RFC1122 verifications. * Alan Cox : rcv_saddr errors. * Alan Cox : Block double connect(). * Alan Cox : Small hooks for enSKIP. * Alexey Kuznetsov: Path MTU discovery. * Alan Cox : Support soft errors. * Alan Cox : Fix MTU discovery pathological case * when the remote claims no mtu! * Marc Tamsky : TCP_CLOSE fix. * Colin (G3TNE) : Send a reset on syn ack replies in * window but wrong (fixes NT lpd problems) * Pedro Roque : Better TCP window handling, delayed ack. * Joerg Reuter : No modification of locked buffers in * tcp_do_retransmit() * Eric Schenk : Changed receiver side silly window * avoidance algorithm to BSD style * algorithm. This doubles throughput * against machines running Solaris, * and seems to result in general * improvement. * Stefan Magdalinski : adjusted tcp_readable() to fix FIONREAD * Willy Konynenberg : Transparent proxying support. * Mike McLagan : Routing by source * Keith Owens : Do proper merging with partial SKB's in * tcp_do_sendmsg to avoid burstiness. * Eric Schenk : Fix fast close down bug with * shutdown() followed by close(). * Andi Kleen : Make poll agree with SIGIO * Salvatore Sanfilippo : Support SO_LINGER with linger == 1 and * lingertime == 0 (RFC 793 ABORT Call) * Hirokazu Takahashi : Use copy_from_user() instead of * csum_and_copy_from_user() if possible. * * Description of States: * * TCP_SYN_SENT sent a connection request, waiting for ack * * TCP_SYN_RECV received a connection request, sent ack, * waiting for final ack in three-way handshake. * * TCP_ESTABLISHED connection established * * TCP_FIN_WAIT1 our side has shutdown, waiting to complete * transmission of remaining buffered data * * TCP_FIN_WAIT2 all buffered data sent, waiting for remote * to shutdown * * TCP_CLOSING both sides have shutdown but we still have * data we have to finish sending * * TCP_TIME_WAIT timeout to catch resent junk before entering * closed, can only be entered from FIN_WAIT2 * or CLOSING. Required because the other end * may not have gotten our last ACK causing it * to retransmit the data packet (which we ignore) * * TCP_CLOSE_WAIT remote side has shutdown and is waiting for * us to finish writing our data and to shutdown * (we have to close() to move on to LAST_ACK) * * TCP_LAST_ACK out side has shutdown after remote has * shutdown. There may still be data in our * buffer that we have to finish sending * * TCP_CLOSE socket is finished */ #define pr_fmt(fmt) "TCP: " fmt #include <crypto/hash.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/types.h> #include <linux/fcntl.h> #include <linux/poll.h> #include <linux/inet_diag.h> #include <linux/init.h> #include <linux/fs.h> #include <linux/skbuff.h> #include <linux/scatterlist.h> #include <linux/splice.h> #include <linux/net.h> #include <linux/socket.h> #include <linux/random.h> #include <linux/memblock.h> #include <linux/highmem.h> #include <linux/cache.h> #include <linux/err.h> #include <linux/time.h> #include <linux/slab.h> #include <linux/errqueue.h> #include <linux/static_key.h> #include <linux/btf.h> #include <net/icmp.h> #include <net/inet_common.h> #include <net/tcp.h> #include <net/mptcp.h> #include <net/xfrm.h> #include <net/ip.h> #include <net/sock.h> #include <linux/uaccess.h> #include <asm/ioctls.h> #include <net/busy_poll.h> /* Track pending CMSGs. */ enum { TCP_CMSG_INQ = 1, TCP_CMSG_TS = 2 }; DEFINE_PER_CPU(unsigned int, tcp_orphan_count); EXPORT_PER_CPU_SYMBOL_GPL(tcp_orphan_count); long sysctl_tcp_mem[3] __read_mostly; EXPORT_SYMBOL(sysctl_tcp_mem); atomic_long_t tcp_memory_allocated ____cacheline_aligned_in_smp; /* Current allocated memory. */ EXPORT_SYMBOL(tcp_memory_allocated); DEFINE_PER_CPU(int, tcp_memory_per_cpu_fw_alloc); EXPORT_PER_CPU_SYMBOL_GPL(tcp_memory_per_cpu_fw_alloc); #if IS_ENABLED(CONFIG_SMC) DEFINE_STATIC_KEY_FALSE(tcp_have_smc); EXPORT_SYMBOL(tcp_have_smc); #endif /* * Current number of TCP sockets. */ struct percpu_counter tcp_sockets_allocated ____cacheline_aligned_in_smp; EXPORT_SYMBOL(tcp_sockets_allocated); /* * TCP splice context */ struct tcp_splice_state { struct pipe_inode_info *pipe; size_t len; unsigned int flags; }; /* * Pressure flag: try to collapse. * Technical note: it is used by multiple contexts non atomically. * All the __sk_mem_schedule() is of this nature: accounting * is strict, actions are advisory and have some latency. */ unsigned long tcp_memory_pressure __read_mostly; EXPORT_SYMBOL_GPL(tcp_memory_pressure); void tcp_enter_memory_pressure(struct sock *sk) { unsigned long val; if (READ_ONCE(tcp_memory_pressure)) return; val = jiffies; if (!val) val--; if (!cmpxchg(&tcp_memory_pressure, 0, val)) NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURES); } EXPORT_SYMBOL_GPL(tcp_enter_memory_pressure); void tcp_leave_memory_pressure(struct sock *sk) { unsigned long val; if (!READ_ONCE(tcp_memory_pressure)) return; val = xchg(&tcp_memory_pressure, 0); if (val) NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURESCHRONO, jiffies_to_msecs(jiffies - val)); } EXPORT_SYMBOL_GPL(tcp_leave_memory_pressure); /* Convert seconds to retransmits based on initial and max timeout */ static u8 secs_to_retrans(int seconds, int timeout, int rto_max) { u8 res = 0; if (seconds > 0) { int period = timeout; res = 1; while (seconds > period && res < 255) { res++; timeout <<= 1; if (timeout > rto_max) timeout = rto_max; period += timeout; } } return res; } /* Convert retransmits to seconds based on initial and max timeout */ static int retrans_to_secs(u8 retrans, int timeout, int rto_max) { int period = 0; if (retrans > 0) { period = timeout; while (--retrans) { timeout <<= 1; if (timeout > rto_max) timeout = rto_max; period += timeout; } } return period; } static u64 tcp_compute_delivery_rate(const struct tcp_sock *tp) { u32 rate = READ_ONCE(tp->rate_delivered); u32 intv = READ_ONCE(tp->rate_interval_us); u64 rate64 = 0; if (rate && intv) { rate64 = (u64)rate * tp->mss_cache * USEC_PER_SEC; do_div(rate64, intv); } return rate64; } /* Address-family independent initialization for a tcp_sock. * * NOTE: A lot of things set to zero explicitly by call to * sk_alloc() so need not be done here. */ void tcp_init_sock(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); tp->out_of_order_queue = RB_ROOT; sk->tcp_rtx_queue = RB_ROOT; tcp_init_xmit_timers(sk); INIT_LIST_HEAD(&tp->tsq_node); INIT_LIST_HEAD(&tp->tsorted_sent_queue); icsk->icsk_rto = TCP_TIMEOUT_INIT; icsk->icsk_rto_min = TCP_RTO_MIN; icsk->icsk_delack_max = TCP_DELACK_MAX; tp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT); minmax_reset(&tp->rtt_min, tcp_jiffies32, ~0U); /* So many TCP implementations out there (incorrectly) count the * initial SYN frame in their delayed-ACK and congestion control * algorithms that we must have the following bandaid to talk * efficiently to them. -DaveM */ tcp_snd_cwnd_set(tp, TCP_INIT_CWND); /* There's a bubble in the pipe until at least the first ACK. */ tp->app_limited = ~0U; tp->rate_app_limited = 1; /* See draft-stevens-tcpca-spec-01 for discussion of the * initialization of these values. */ tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tp->snd_cwnd_clamp = ~0; tp->mss_cache = TCP_MSS_DEFAULT; tp->reordering = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reordering); tcp_assign_congestion_control(sk); tp->tsoffset = 0; tp->rack.reo_wnd_steps = 1; sk->sk_write_space = sk_stream_write_space; sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); icsk->icsk_sync_mss = tcp_sync_mss; WRITE_ONCE(sk->sk_sndbuf, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[1])); WRITE_ONCE(sk->sk_rcvbuf, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[1])); tcp_scaling_ratio_init(sk); set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); sk_sockets_allocated_inc(sk); } EXPORT_SYMBOL(tcp_init_sock); static void tcp_tx_timestamp(struct sock *sk, u16 tsflags) { struct sk_buff *skb = tcp_write_queue_tail(sk); if (tsflags && skb) { struct skb_shared_info *shinfo = skb_shinfo(skb); struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); sock_tx_timestamp(sk, tsflags, &shinfo->tx_flags); if (tsflags & SOF_TIMESTAMPING_TX_ACK) tcb->txstamp_ack = 1; if (tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) shinfo->tskey = TCP_SKB_CB(skb)->seq + skb->len - 1; } } static bool tcp_stream_is_readable(struct sock *sk, int target) { if (tcp_epollin_ready(sk, target)) return true; return sk_is_readable(sk); } /* * Wait for a TCP event. * * Note that we don't need to lock the socket, as the upper poll layers * take care of normal races (between the test and the event) and we don't * go look at any of the socket buffers directly. */ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait) { __poll_t mask; struct sock *sk = sock->sk; const struct tcp_sock *tp = tcp_sk(sk); u8 shutdown; int state; sock_poll_wait(file, sock, wait); state = inet_sk_state_load(sk); if (state == TCP_LISTEN) return inet_csk_listen_poll(sk); /* Socket is not locked. We are protected from async events * by poll logic and correct handling of state changes * made by other threads is impossible in any case. */ mask = 0; /* * EPOLLHUP is certainly not done right. But poll() doesn't * have a notion of HUP in just one direction, and for a * socket the read side is more interesting. * * Some poll() documentation says that EPOLLHUP is incompatible * with the EPOLLOUT/POLLWR flags, so somebody should check this * all. But careful, it tends to be safer to return too many * bits than too few, and you can easily break real applications * if you don't tell them that something has hung up! * * Check-me. * * Check number 1. EPOLLHUP is _UNMASKABLE_ event (see UNIX98 and * our fs/select.c). It means that after we received EOF, * poll always returns immediately, making impossible poll() on write() * in state CLOSE_WAIT. One solution is evident --- to set EPOLLHUP * if and only if shutdown has been made in both directions. * Actually, it is interesting to look how Solaris and DUX * solve this dilemma. I would prefer, if EPOLLHUP were maskable, * then we could set it on SND_SHUTDOWN. BTW examples given * in Stevens' books assume exactly this behaviour, it explains * why EPOLLHUP is incompatible with EPOLLOUT. --ANK * * NOTE. Check for TCP_CLOSE is added. The goal is to prevent * blocking on fresh not-connected or disconnected socket. --ANK */ shutdown = READ_ONCE(sk->sk_shutdown); if (shutdown == SHUTDOWN_MASK || state == TCP_CLOSE) mask |= EPOLLHUP; if (shutdown & RCV_SHUTDOWN) mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP; /* Connected or passive Fast Open socket? */ if (state != TCP_SYN_SENT && (state != TCP_SYN_RECV || rcu_access_pointer(tp->fastopen_rsk))) { int target = sock_rcvlowat(sk, 0, INT_MAX); u16 urg_data = READ_ONCE(tp->urg_data); if (unlikely(urg_data) && READ_ONCE(tp->urg_seq) == READ_ONCE(tp->copied_seq) && !sock_flag(sk, SOCK_URGINLINE)) target++; if (tcp_stream_is_readable(sk, target)) mask |= EPOLLIN | EPOLLRDNORM; if (!(shutdown & SEND_SHUTDOWN)) { if (__sk_stream_is_writeable(sk, 1)) { mask |= EPOLLOUT | EPOLLWRNORM; } else { /* send SIGIO later */ sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); /* Race breaker. If space is freed after * wspace test but before the flags are set, * IO signal will be lost. Memory barrier * pairs with the input side. */ smp_mb__after_atomic(); if (__sk_stream_is_writeable(sk, 1)) mask |= EPOLLOUT | EPOLLWRNORM; } } else mask |= EPOLLOUT | EPOLLWRNORM; if (urg_data & TCP_URG_VALID) mask |= EPOLLPRI; } else if (state == TCP_SYN_SENT && inet_test_bit(DEFER_CONNECT, sk)) { /* Active TCP fastopen socket with defer_connect * Return EPOLLOUT so application can call write() * in order for kernel to generate SYN+data */ mask |= EPOLLOUT | EPOLLWRNORM; } /* This barrier is coupled with smp_wmb() in tcp_reset() */ smp_rmb(); if (READ_ONCE(sk->sk_err) || !skb_queue_empty_lockless(&sk->sk_error_queue)) mask |= EPOLLERR; return mask; } EXPORT_SYMBOL(tcp_poll); int tcp_ioctl(struct sock *sk, int cmd, int *karg) { struct tcp_sock *tp = tcp_sk(sk); int answ; bool slow; switch (cmd) { case SIOCINQ: if (sk->sk_state == TCP_LISTEN) return -EINVAL; slow = lock_sock_fast(sk); answ = tcp_inq(sk); unlock_sock_fast(sk, slow); break; case SIOCATMARK: answ = READ_ONCE(tp->urg_data) && READ_ONCE(tp->urg_seq) == READ_ONCE(tp->copied_seq); break; case SIOCOUTQ: if (sk->sk_state == TCP_LISTEN) return -EINVAL; if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) answ = 0; else answ = READ_ONCE(tp->write_seq) - tp->snd_una; break; case SIOCOUTQNSD: if (sk->sk_state == TCP_LISTEN) return -EINVAL; if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) answ = 0; else answ = READ_ONCE(tp->write_seq) - READ_ONCE(tp->snd_nxt); break; default: return -ENOIOCTLCMD; } *karg = answ; return 0; } EXPORT_SYMBOL(tcp_ioctl); void tcp_mark_push(struct tcp_sock *tp, struct sk_buff *skb) { TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_PSH; tp->pushed_seq = tp->write_seq; } static inline bool forced_push(const struct tcp_sock *tp) { return after(tp->write_seq, tp->pushed_seq + (tp->max_window >> 1)); } void tcp_skb_entail(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); tcb->seq = tcb->end_seq = tp->write_seq; tcb->tcp_flags = TCPHDR_ACK; __skb_header_release(skb); tcp_add_write_queue_tail(sk, skb); sk_wmem_queued_add(sk, skb->truesize); sk_mem_charge(sk, skb->truesize); if (tp->nonagle & TCP_NAGLE_PUSH) tp->nonagle &= ~TCP_NAGLE_PUSH; tcp_slow_start_after_idle_check(sk); } static inline void tcp_mark_urg(struct tcp_sock *tp, int flags) { if (flags & MSG_OOB) tp->snd_up = tp->write_seq; } /* If a not yet filled skb is pushed, do not send it if * we have data packets in Qdisc or NIC queues : * Because TX completion will happen shortly, it gives a chance * to coalesce future sendmsg() payload into this skb, without * need for a timer, and with no latency trade off. * As packets containing data payload have a bigger truesize * than pure acks (dataless) packets, the last checks prevent * autocorking if we only have an ACK in Qdisc/NIC queues, * or if TX completion was delayed after we processed ACK packet. */ static bool tcp_should_autocork(struct sock *sk, struct sk_buff *skb, int size_goal) { return skb->len < size_goal && READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_autocorking) && !tcp_rtx_queue_empty(sk) && refcount_read(&sk->sk_wmem_alloc) > skb->truesize && tcp_skb_can_collapse_to(skb); } void tcp_push(struct sock *sk, int flags, int mss_now, int nonagle, int size_goal) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; skb = tcp_write_queue_tail(sk); if (!skb) return; if (!(flags & MSG_MORE) || forced_push(tp)) tcp_mark_push(tp, skb); tcp_mark_urg(tp, flags); if (tcp_should_autocork(sk, skb, size_goal)) { /* avoid atomic op if TSQ_THROTTLED bit is already set */ if (!test_bit(TSQ_THROTTLED, &sk->sk_tsq_flags)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAUTOCORKING); set_bit(TSQ_THROTTLED, &sk->sk_tsq_flags); } /* It is possible TX completion already happened * before we set TSQ_THROTTLED. */ if (refcount_read(&sk->sk_wmem_alloc) > skb->truesize) return; } if (flags & MSG_MORE) nonagle = TCP_NAGLE_CORK; __tcp_push_pending_frames(sk, mss_now, nonagle); } static int tcp_splice_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len) { struct tcp_splice_state *tss = rd_desc->arg.data; int ret; ret = skb_splice_bits(skb, skb->sk, offset, tss->pipe, min(rd_desc->count, len), tss->flags); if (ret > 0) rd_desc->count -= ret; return ret; } static int __tcp_splice_read(struct sock *sk, struct tcp_splice_state *tss) { /* Store TCP splice context information in read_descriptor_t. */ read_descriptor_t rd_desc = { .arg.data = tss, .count = tss->len, }; return tcp_read_sock(sk, &rd_desc, tcp_splice_data_recv); } /** * tcp_splice_read - splice data from TCP socket to a pipe * @sock: socket to splice from * @ppos: position (not valid) * @pipe: pipe to splice to * @len: number of bytes to splice * @flags: splice modifier flags * * Description: * Will read pages from given socket and fill them into a pipe. * **/ ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { struct sock *sk = sock->sk; struct tcp_splice_state tss = { .pipe = pipe, .len = len, .flags = flags, }; long timeo; ssize_t spliced; int ret; sock_rps_record_flow(sk); /* * We can't seek on a socket input */ if (unlikely(*ppos)) return -ESPIPE; ret = spliced = 0; lock_sock(sk); timeo = sock_rcvtimeo(sk, sock->file->f_flags & O_NONBLOCK); while (tss.len) { ret = __tcp_splice_read(sk, &tss); if (ret < 0) break; else if (!ret) { if (spliced) break; if (sock_flag(sk, SOCK_DONE)) break; if (sk->sk_err) { ret = sock_error(sk); break; } if (sk->sk_shutdown & RCV_SHUTDOWN) break; if (sk->sk_state == TCP_CLOSE) { /* * This occurs when user tries to read * from never connected socket. */ ret = -ENOTCONN; break; } if (!timeo) { ret = -EAGAIN; break; } /* if __tcp_splice_read() got nothing while we have * an skb in receive queue, we do not want to loop. * This might happen with URG data. */ if (!skb_queue_empty(&sk->sk_receive_queue)) break; sk_wait_data(sk, &timeo, NULL); if (signal_pending(current)) { ret = sock_intr_errno(timeo); break; } continue; } tss.len -= ret; spliced += ret; if (!tss.len || !timeo) break; release_sock(sk); lock_sock(sk); if (sk->sk_err || sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN) || signal_pending(current)) break; } release_sock(sk); if (spliced) return spliced; return ret; } EXPORT_SYMBOL(tcp_splice_read); struct sk_buff *tcp_stream_alloc_skb(struct sock *sk, gfp_t gfp, bool force_schedule) { struct sk_buff *skb; skb = alloc_skb_fclone(MAX_TCP_HEADER, gfp); if (likely(skb)) { bool mem_scheduled; skb->truesize = SKB_TRUESIZE(skb_end_offset(skb)); if (force_schedule) { mem_scheduled = true; sk_forced_mem_schedule(sk, skb->truesize); } else { mem_scheduled = sk_wmem_schedule(sk, skb->truesize); } if (likely(mem_scheduled)) { skb_reserve(skb, MAX_TCP_HEADER); skb->ip_summed = CHECKSUM_PARTIAL; INIT_LIST_HEAD(&skb->tcp_tsorted_anchor); return skb; } __kfree_skb(skb); } else { sk->sk_prot->enter_memory_pressure(sk); sk_stream_moderate_sndbuf(sk); } return NULL; } static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now, int large_allowed) { struct tcp_sock *tp = tcp_sk(sk); u32 new_size_goal, size_goal; if (!large_allowed) return mss_now; /* Note : tcp_tso_autosize() will eventually split this later */ new_size_goal = tcp_bound_to_half_wnd(tp, sk->sk_gso_max_size); /* We try hard to avoid divides here */ size_goal = tp->gso_segs * mss_now; if (unlikely(new_size_goal < size_goal || new_size_goal >= size_goal + mss_now)) { tp->gso_segs = min_t(u16, new_size_goal / mss_now, sk->sk_gso_max_segs); size_goal = tp->gso_segs * mss_now; } return max(size_goal, mss_now); } int tcp_send_mss(struct sock *sk, int *size_goal, int flags) { int mss_now; mss_now = tcp_current_mss(sk); *size_goal = tcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB)); return mss_now; } /* In some cases, both sendmsg() could have added an skb to the write queue, * but failed adding payload on it. We need to remove it to consume less * memory, but more importantly be able to generate EPOLLOUT for Edge Trigger * epoll() users. */ void tcp_remove_empty_skb(struct sock *sk) { struct sk_buff *skb = tcp_write_queue_tail(sk); if (skb && TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) { tcp_unlink_write_queue(skb, sk); if (tcp_write_queue_empty(sk)) tcp_chrono_stop(sk, TCP_CHRONO_BUSY); tcp_wmem_free_skb(sk, skb); } } /* skb changing from pure zc to mixed, must charge zc */ static int tcp_downgrade_zcopy_pure(struct sock *sk, struct sk_buff *skb) { if (unlikely(skb_zcopy_pure(skb))) { u32 extra = skb->truesize - SKB_TRUESIZE(skb_end_offset(skb)); if (!sk_wmem_schedule(sk, extra)) return -ENOMEM; sk_mem_charge(sk, extra); skb_shinfo(skb)->flags &= ~SKBFL_PURE_ZEROCOPY; } return 0; } int tcp_wmem_schedule(struct sock *sk, int copy) { int left; if (likely(sk_wmem_schedule(sk, copy))) return copy; /* We could be in trouble if we have nothing queued. * Use whatever is left in sk->sk_forward_alloc and tcp_wmem[0] * to guarantee some progress. */ left = sock_net(sk)->ipv4.sysctl_tcp_wmem[0] - sk->sk_wmem_queued; if (left > 0) sk_forced_mem_schedule(sk, min(left, copy)); return min(copy, sk->sk_forward_alloc); } void tcp_free_fastopen_req(struct tcp_sock *tp) { if (tp->fastopen_req) { kfree(tp->fastopen_req); tp->fastopen_req = NULL; } } int tcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg, int *copied, size_t size, struct ubuf_info *uarg) { struct tcp_sock *tp = tcp_sk(sk); struct inet_sock *inet = inet_sk(sk); struct sockaddr *uaddr = msg->msg_name; int err, flags; if (!(READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen) & TFO_CLIENT_ENABLE) || (uaddr && msg->msg_namelen >= sizeof(uaddr->sa_family) && uaddr->sa_family == AF_UNSPEC)) return -EOPNOTSUPP; if (tp->fastopen_req) return -EALREADY; /* Another Fast Open is in progress */ tp->fastopen_req = kzalloc(sizeof(struct tcp_fastopen_request), sk->sk_allocation); if (unlikely(!tp->fastopen_req)) return -ENOBUFS; tp->fastopen_req->data = msg; tp->fastopen_req->size = size; tp->fastopen_req->uarg = uarg; if (inet_test_bit(DEFER_CONNECT, sk)) { err = tcp_connect(sk); /* Same failure procedure as in tcp_v4/6_connect */ if (err) { tcp_set_state(sk, TCP_CLOSE); inet->inet_dport = 0; sk->sk_route_caps = 0; } } flags = (msg->msg_flags & MSG_DONTWAIT) ? O_NONBLOCK : 0; err = __inet_stream_connect(sk->sk_socket, uaddr, msg->msg_namelen, flags, 1); /* fastopen_req could already be freed in __inet_stream_connect * if the connection times out or gets rst */ if (tp->fastopen_req) { *copied = tp->fastopen_req->copied; tcp_free_fastopen_req(tp); inet_clear_bit(DEFER_CONNECT, sk); } return err; } int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) { struct tcp_sock *tp = tcp_sk(sk); struct ubuf_info *uarg = NULL; struct sk_buff *skb; struct sockcm_cookie sockc; int flags, err, copied = 0; int mss_now = 0, size_goal, copied_syn = 0; int process_backlog = 0; int zc = 0; long timeo; flags = msg->msg_flags; if ((flags & MSG_ZEROCOPY) && size) { if (msg->msg_ubuf) { uarg = msg->msg_ubuf; if (sk->sk_route_caps & NETIF_F_SG) zc = MSG_ZEROCOPY; } else if (sock_flag(sk, SOCK_ZEROCOPY)) { skb = tcp_write_queue_tail(sk); uarg = msg_zerocopy_realloc(sk, size, skb_zcopy(skb)); if (!uarg) { err = -ENOBUFS; goto out_err; } if (sk->sk_route_caps & NETIF_F_SG) zc = MSG_ZEROCOPY; else uarg_to_msgzc(uarg)->zerocopy = 0; } } else if (unlikely(msg->msg_flags & MSG_SPLICE_PAGES) && size) { if (sk->sk_route_caps & NETIF_F_SG) zc = MSG_SPLICE_PAGES; } if (unlikely(flags & MSG_FASTOPEN || inet_test_bit(DEFER_CONNECT, sk)) && !tp->repair) { err = tcp_sendmsg_fastopen(sk, msg, &copied_syn, size, uarg); if (err == -EINPROGRESS && copied_syn > 0) goto out; else if (err) goto out_err; } timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); tcp_rate_check_app_limited(sk); /* is sending application-limited? */ /* Wait for a connection to finish. One exception is TCP Fast Open * (passive side) where data is allowed to be sent before a connection * is fully established. */ if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) && !tcp_passive_fastopen(sk)) { err = sk_stream_wait_connect(sk, &timeo); if (err != 0) goto do_error; } if (unlikely(tp->repair)) { if (tp->repair_queue == TCP_RECV_QUEUE) { copied = tcp_send_rcvq(sk, msg, size); goto out_nopush; } err = -EINVAL; if (tp->repair_queue == TCP_NO_QUEUE) goto out_err; /* 'common' sending to sendq */ } sockcm_init(&sockc, sk); if (msg->msg_controllen) { err = sock_cmsg_send(sk, msg, &sockc); if (unlikely(err)) { err = -EINVAL; goto out_err; } } /* This should be in poll */ sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); /* Ok commence sending. */ copied = 0; restart: mss_now = tcp_send_mss(sk, &size_goal, flags); err = -EPIPE; if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) goto do_error; while (msg_data_left(msg)) { ssize_t copy = 0; skb = tcp_write_queue_tail(sk); if (skb) copy = size_goal - skb->len; if (copy <= 0 || !tcp_skb_can_collapse_to(skb)) { bool first_skb; new_segment: if (!sk_stream_memory_free(sk)) goto wait_for_space; if (unlikely(process_backlog >= 16)) { process_backlog = 0; if (sk_flush_backlog(sk)) goto restart; } first_skb = tcp_rtx_and_write_queues_empty(sk); skb = tcp_stream_alloc_skb(sk, sk->sk_allocation, first_skb); if (!skb) goto wait_for_space; process_backlog++; tcp_skb_entail(sk, skb); copy = size_goal; /* All packets are restored as if they have * already been sent. skb_mstamp_ns isn't set to * avoid wrong rtt estimation. */ if (tp->repair) TCP_SKB_CB(skb)->sacked |= TCPCB_REPAIRED; } /* Try to append data to the end of skb. */ if (copy > msg_data_left(msg)) copy = msg_data_left(msg); if (zc == 0) { bool merge = true; int i = skb_shinfo(skb)->nr_frags; struct page_frag *pfrag = sk_page_frag(sk); if (!sk_page_frag_refill(sk, pfrag)) goto wait_for_space; if (!skb_can_coalesce(skb, i, pfrag->page, pfrag->offset)) { if (i >= READ_ONCE(sysctl_max_skb_frags)) { tcp_mark_push(tp, skb); goto new_segment; } merge = false; } copy = min_t(int, copy, pfrag->size - pfrag->offset); if (unlikely(skb_zcopy_pure(skb) || skb_zcopy_managed(skb))) { if (tcp_downgrade_zcopy_pure(sk, skb)) goto wait_for_space; skb_zcopy_downgrade_managed(skb); } copy = tcp_wmem_schedule(sk, copy); if (!copy) goto wait_for_space; err = skb_copy_to_page_nocache(sk, &msg->msg_iter, skb, pfrag->page, pfrag->offset, copy); if (err) goto do_error; /* Update the skb. */ if (merge) { skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); } else { skb_fill_page_desc(skb, i, pfrag->page, pfrag->offset, copy); page_ref_inc(pfrag->page); } pfrag->offset += copy; } else if (zc == MSG_ZEROCOPY) { /* First append to a fragless skb builds initial * pure zerocopy skb */ if (!skb->len) skb_shinfo(skb)->flags |= SKBFL_PURE_ZEROCOPY; if (!skb_zcopy_pure(skb)) { copy = tcp_wmem_schedule(sk, copy); if (!copy) goto wait_for_space; } err = skb_zerocopy_iter_stream(sk, skb, msg, copy, uarg); if (err == -EMSGSIZE || err == -EEXIST) { tcp_mark_push(tp, skb); goto new_segment; } if (err < 0) goto do_error; copy = err; } else if (zc == MSG_SPLICE_PAGES) { /* Splice in data if we can; copy if we can't. */ if (tcp_downgrade_zcopy_pure(sk, skb)) goto wait_for_space; copy = tcp_wmem_schedule(sk, copy); if (!copy) goto wait_for_space; err = skb_splice_from_iter(skb, &msg->msg_iter, copy, sk->sk_allocation); if (err < 0) { if (err == -EMSGSIZE) { tcp_mark_push(tp, skb); goto new_segment; } goto do_error; } copy = err; if (!(flags & MSG_NO_SHARED_FRAGS)) skb_shinfo(skb)->flags |= SKBFL_SHARED_FRAG; sk_wmem_queued_add(sk, copy); sk_mem_charge(sk, copy); } if (!copied) TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH; WRITE_ONCE(tp->write_seq, tp->write_seq + copy); TCP_SKB_CB(skb)->end_seq += copy; tcp_skb_pcount_set(skb, 0); copied += copy; if (!msg_data_left(msg)) { if (unlikely(flags & MSG_EOR)) TCP_SKB_CB(skb)->eor = 1; goto out; } if (skb->len < size_goal || (flags & MSG_OOB) || unlikely(tp->repair)) continue; if (forced_push(tp)) { tcp_mark_push(tp, skb); __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH); } else if (skb == tcp_send_head(sk)) tcp_push_one(sk, mss_now); continue; wait_for_space: set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); if (copied) tcp_push(sk, flags & ~MSG_MORE, mss_now, TCP_NAGLE_PUSH, size_goal); err = sk_stream_wait_memory(sk, &timeo); if (err != 0) goto do_error; mss_now = tcp_send_mss(sk, &size_goal, flags); } out: if (copied) { tcp_tx_timestamp(sk, sockc.tsflags); tcp_push(sk, flags, mss_now, tp->nonagle, size_goal); } out_nopush: /* msg->msg_ubuf is pinned by the caller so we don't take extra refs */ if (uarg && !msg->msg_ubuf) net_zcopy_put(uarg); return copied + copied_syn; do_error: tcp_remove_empty_skb(sk); if (copied + copied_syn) goto out; out_err: /* msg->msg_ubuf is pinned by the caller so we don't take extra refs */ if (uarg && !msg->msg_ubuf) net_zcopy_put_abort(uarg, true); err = sk_stream_error(sk, flags, err); /* make sure we wake any epoll edge trigger waiter */ if (unlikely(tcp_rtx_and_write_queues_empty(sk) && err == -EAGAIN)) { sk->sk_write_space(sk); tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED); } return err; } EXPORT_SYMBOL_GPL(tcp_sendmsg_locked); int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) { int ret; lock_sock(sk); ret = tcp_sendmsg_locked(sk, msg, size); release_sock(sk); return ret; } EXPORT_SYMBOL(tcp_sendmsg); void tcp_splice_eof(struct socket *sock) { struct sock *sk = sock->sk; struct tcp_sock *tp = tcp_sk(sk); int mss_now, size_goal; if (!tcp_write_queue_tail(sk)) return; lock_sock(sk); mss_now = tcp_send_mss(sk, &size_goal, 0); tcp_push(sk, 0, mss_now, tp->nonagle, size_goal); release_sock(sk); } EXPORT_SYMBOL_GPL(tcp_splice_eof); /* * Handle reading urgent data. BSD has very simple semantics for * this, no blocking and very strange errors 8) */ static int tcp_recv_urg(struct sock *sk, struct msghdr *msg, int len, int flags) { struct tcp_sock *tp = tcp_sk(sk); /* No URG data to read. */ if (sock_flag(sk, SOCK_URGINLINE) || !tp->urg_data || tp->urg_data == TCP_URG_READ) return -EINVAL; /* Yes this is right ! */ if (sk->sk_state == TCP_CLOSE && !sock_flag(sk, SOCK_DONE)) return -ENOTCONN; if (tp->urg_data & TCP_URG_VALID) { int err = 0; char c = tp->urg_data; if (!(flags & MSG_PEEK)) WRITE_ONCE(tp->urg_data, TCP_URG_READ); /* Read urgent data. */ msg->msg_flags |= MSG_OOB; if (len > 0) { if (!(flags & MSG_TRUNC)) err = memcpy_to_msg(msg, &c, 1); len = 1; } else msg->msg_flags |= MSG_TRUNC; return err ? -EFAULT : len; } if (sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN)) return 0; /* Fixed the recv(..., MSG_OOB) behaviour. BSD docs and * the available implementations agree in this case: * this call should never block, independent of the * blocking state of the socket. * Mike <[email protected]> */ return -EAGAIN; } static int tcp_peek_sndq(struct sock *sk, struct msghdr *msg, int len) { struct sk_buff *skb; int copied = 0, err = 0; /* XXX -- need to support SO_PEEK_OFF */ skb_rbtree_walk(skb, &sk->tcp_rtx_queue) { err = skb_copy_datagram_msg(skb, 0, msg, skb->len); if (err) return err; copied += skb->len; } skb_queue_walk(&sk->sk_write_queue, skb) { err = skb_copy_datagram_msg(skb, 0, msg, skb->len); if (err) break; copied += skb->len; } return err ?: copied; } /* Clean up the receive buffer for full frames taken by the user, * then send an ACK if necessary. COPIED is the number of bytes * tcp_recvmsg has given to the user so far, it speeds up the * calculation of whether or not we must ACK for the sake of * a window update. */ void __tcp_cleanup_rbuf(struct sock *sk, int copied) { struct tcp_sock *tp = tcp_sk(sk); bool time_to_ack = false; if (inet_csk_ack_scheduled(sk)) { const struct inet_connection_sock *icsk = inet_csk(sk); if (/* Once-per-two-segments ACK was not sent by tcp_input.c */ tp->rcv_nxt - tp->rcv_wup > icsk->icsk_ack.rcv_mss || /* * If this read emptied read buffer, we send ACK, if * connection is not bidirectional, user drained * receive buffer and there was a small segment * in queue. */ (copied > 0 && ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED2) || ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED) && !inet_csk_in_pingpong_mode(sk))) && !atomic_read(&sk->sk_rmem_alloc))) time_to_ack = true; } /* We send an ACK if we can now advertise a non-zero window * which has been raised "significantly". * * Even if window raised up to infinity, do not send window open ACK * in states, where we will not receive more. It is useless. */ if (copied > 0 && !time_to_ack && !(sk->sk_shutdown & RCV_SHUTDOWN)) { __u32 rcv_window_now = tcp_receive_window(tp); /* Optimize, __tcp_select_window() is not cheap. */ if (2*rcv_window_now <= tp->window_clamp) { __u32 new_window = __tcp_select_window(sk); /* Send ACK now, if this read freed lots of space * in our buffer. Certainly, new_window is new window. * We can advertise it now, if it is not less than current one. * "Lots" means "at least twice" here. */ if (new_window && new_window >= 2 * rcv_window_now) time_to_ack = true; } } if (time_to_ack) tcp_send_ack(sk); } void tcp_cleanup_rbuf(struct sock *sk, int copied) { struct sk_buff *skb = skb_peek(&sk->sk_receive_queue); struct tcp_sock *tp = tcp_sk(sk); WARN(skb && !before(tp->copied_seq, TCP_SKB_CB(skb)->end_seq), "cleanup rbuf bug: copied %X seq %X rcvnxt %X\n", tp->copied_seq, TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt); __tcp_cleanup_rbuf(sk, copied); } static void tcp_eat_recv_skb(struct sock *sk, struct sk_buff *skb) { __skb_unlink(skb, &sk->sk_receive_queue); if (likely(skb->destructor == sock_rfree)) { sock_rfree(skb); skb->destructor = NULL; skb->sk = NULL; return skb_attempt_defer_free(skb); } __kfree_skb(skb); } struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off) { struct sk_buff *skb; u32 offset; while ((skb = skb_peek(&sk->sk_receive_queue)) != NULL) { offset = seq - TCP_SKB_CB(skb)->seq; if (unlikely(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) { pr_err_once("%s: found a SYN, please report !\n", __func__); offset--; } if (offset < skb->len || (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) { *off = offset; return skb; } /* This looks weird, but this can happen if TCP collapsing * splitted a fat GRO packet, while we released socket lock * in skb_splice_bits() */ tcp_eat_recv_skb(sk, skb); } return NULL; } EXPORT_SYMBOL(tcp_recv_skb); /* * This routine provides an alternative to tcp_recvmsg() for routines * that would like to handle copying from skbuffs directly in 'sendfile' * fashion. * Note: * - It is assumed that the socket was locked by the caller. * - The routine does not block. * - At present, there is no support for reading OOB data * or for 'peeking' the socket using this routine * (although both would be easy to implement). */ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, sk_read_actor_t recv_actor) { struct sk_buff *skb; struct tcp_sock *tp = tcp_sk(sk); u32 seq = tp->copied_seq; u32 offset; int copied = 0; if (sk->sk_state == TCP_LISTEN) return -ENOTCONN; while ((skb = tcp_recv_skb(sk, seq, &offset)) != NULL) { if (offset < skb->len) { int used; size_t len; len = skb->len - offset; /* Stop reading if we hit a patch of urgent data */ if (unlikely(tp->urg_data)) { u32 urg_offset = tp->urg_seq - seq; if (urg_offset < len) len = urg_offset; if (!len) break; } used = recv_actor(desc, skb, offset, len); if (used <= 0) { if (!copied) copied = used; break; } if (WARN_ON_ONCE(used > len)) used = len; seq += used; copied += used; offset += used; /* If recv_actor drops the lock (e.g. TCP splice * receive) the skb pointer might be invalid when * getting here: tcp_collapse might have deleted it * while aggregating skbs from the socket queue. */ skb = tcp_recv_skb(sk, seq - 1, &offset); if (!skb) break; /* TCP coalescing might have appended data to the skb. * Try to splice more frags */ if (offset + 1 != skb->len) continue; } if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) { tcp_eat_recv_skb(sk, skb); ++seq; break; } tcp_eat_recv_skb(sk, skb); if (!desc->count) break; WRITE_ONCE(tp->copied_seq, seq); } WRITE_ONCE(tp->copied_seq, seq); tcp_rcv_space_adjust(sk); /* Clean up data we have read: This will do ACK frames. */ if (copied > 0) { tcp_recv_skb(sk, seq, &offset); tcp_cleanup_rbuf(sk, copied); } return copied; } EXPORT_SYMBOL(tcp_read_sock); int tcp_read_skb(struct sock *sk, skb_read_actor_t recv_actor) { struct tcp_sock *tp = tcp_sk(sk); u32 seq = tp->copied_seq; struct sk_buff *skb; int copied = 0; u32 offset; if (sk->sk_state == TCP_LISTEN) return -ENOTCONN; while ((skb = tcp_recv_skb(sk, seq, &offset)) != NULL) { u8 tcp_flags; int used; __skb_unlink(skb, &sk->sk_receive_queue); WARN_ON_ONCE(!skb_set_owner_sk_safe(skb, sk)); tcp_flags = TCP_SKB_CB(skb)->tcp_flags; used = recv_actor(sk, skb); if (used < 0) { if (!copied) copied = used; break; } seq += used; copied += used; if (tcp_flags & TCPHDR_FIN) { ++seq; break; } } return copied; } EXPORT_SYMBOL(tcp_read_skb); void tcp_read_done(struct sock *sk, size_t len) { struct tcp_sock *tp = tcp_sk(sk); u32 seq = tp->copied_seq; struct sk_buff *skb; size_t left; u32 offset; if (sk->sk_state == TCP_LISTEN) return; left = len; while (left && (skb = tcp_recv_skb(sk, seq, &offset)) != NULL) { int used; used = min_t(size_t, skb->len - offset, left); seq += used; left -= used; if (skb->len > offset + used) break; if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) { tcp_eat_recv_skb(sk, skb); ++seq; break; } tcp_eat_recv_skb(sk, skb); } WRITE_ONCE(tp->copied_seq, seq); tcp_rcv_space_adjust(sk); /* Clean up data we have read: This will do ACK frames. */ if (left != len) tcp_cleanup_rbuf(sk, len - left); } EXPORT_SYMBOL(tcp_read_done); int tcp_peek_len(struct socket *sock) { return tcp_inq(sock->sk); } EXPORT_SYMBOL(tcp_peek_len); /* Make sure sk_rcvbuf is big enough to satisfy SO_RCVLOWAT hint */ int tcp_set_rcvlowat(struct sock *sk, int val) { int space, cap; if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) cap = sk->sk_rcvbuf >> 1; else cap = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2]) >> 1; val = min(val, cap); WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); /* Check if we need to signal EPOLLIN right now */ tcp_data_ready(sk); if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) return 0; space = tcp_space_from_win(sk, val); if (space > sk->sk_rcvbuf) { WRITE_ONCE(sk->sk_rcvbuf, space); tcp_sk(sk)->window_clamp = val; } return 0; } EXPORT_SYMBOL(tcp_set_rcvlowat); void tcp_update_recv_tstamps(struct sk_buff *skb, struct scm_timestamping_internal *tss) { if (skb->tstamp) tss->ts[0] = ktime_to_timespec64(skb->tstamp); else tss->ts[0] = (struct timespec64) {0}; if (skb_hwtstamps(skb)->hwtstamp) tss->ts[2] = ktime_to_timespec64(skb_hwtstamps(skb)->hwtstamp); else tss->ts[2] = (struct timespec64) {0}; } #ifdef CONFIG_MMU static const struct vm_operations_struct tcp_vm_ops = { }; int tcp_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) { if (vma->vm_flags & (VM_WRITE | VM_EXEC)) return -EPERM; vm_flags_clear(vma, VM_MAYWRITE | VM_MAYEXEC); /* Instruct vm_insert_page() to not mmap_read_lock(mm) */ vm_flags_set(vma, VM_MIXEDMAP); vma->vm_ops = &tcp_vm_ops; return 0; } EXPORT_SYMBOL(tcp_mmap); static skb_frag_t *skb_advance_to_frag(struct sk_buff *skb, u32 offset_skb, u32 *offset_frag) { skb_frag_t *frag; if (unlikely(offset_skb >= skb->len)) return NULL; offset_skb -= skb_headlen(skb); if ((int)offset_skb < 0 || skb_has_frag_list(skb)) return NULL; frag = skb_shinfo(skb)->frags; while (offset_skb) { if (skb_frag_size(frag) > offset_skb) { *offset_frag = offset_skb; return frag; } offset_skb -= skb_frag_size(frag); ++frag; } *offset_frag = 0; return frag; } static bool can_map_frag(const skb_frag_t *frag) { return skb_frag_size(frag) == PAGE_SIZE && !skb_frag_off(frag); } static int find_next_mappable_frag(const skb_frag_t *frag, int remaining_in_skb) { int offset = 0; if (likely(can_map_frag(frag))) return 0; while (offset < remaining_in_skb && !can_map_frag(frag)) { offset += skb_frag_size(frag); ++frag; } return offset; } static void tcp_zerocopy_set_hint_for_skb(struct sock *sk, struct tcp_zerocopy_receive *zc, struct sk_buff *skb, u32 offset) { u32 frag_offset, partial_frag_remainder = 0; int mappable_offset; skb_frag_t *frag; /* worst case: skip to next skb. try to improve on this case below */ zc->recv_skip_hint = skb->len - offset; /* Find the frag containing this offset (and how far into that frag) */ frag = skb_advance_to_frag(skb, offset, &frag_offset); if (!frag) return; if (frag_offset) { struct skb_shared_info *info = skb_shinfo(skb); /* We read part of the last frag, must recvmsg() rest of skb. */ if (frag == &info->frags[info->nr_frags - 1]) return; /* Else, we must at least read the remainder in this frag. */ partial_frag_remainder = skb_frag_size(frag) - frag_offset; zc->recv_skip_hint -= partial_frag_remainder; ++frag; } /* partial_frag_remainder: If part way through a frag, must read rest. * mappable_offset: Bytes till next mappable frag, *not* counting bytes * in partial_frag_remainder. */ mappable_offset = find_next_mappable_frag(frag, zc->recv_skip_hint); zc->recv_skip_hint = mappable_offset + partial_frag_remainder; } static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len, int flags, struct scm_timestamping_internal *tss, int *cmsg_flags); static int receive_fallback_to_copy(struct sock *sk, struct tcp_zerocopy_receive *zc, int inq, struct scm_timestamping_internal *tss) { unsigned long copy_address = (unsigned long)zc->copybuf_address; struct msghdr msg = {}; struct iovec iov; int err; zc->length = 0; zc->recv_skip_hint = 0; if (copy_address != zc->copybuf_address) return -EINVAL; err = import_single_range(ITER_DEST, (void __user *)copy_address, inq, &iov, &msg.msg_iter); if (err) return err; err = tcp_recvmsg_locked(sk, &msg, inq, MSG_DONTWAIT, tss, &zc->msg_flags); if (err < 0) return err; zc->copybuf_len = err; if (likely(zc->copybuf_len)) { struct sk_buff *skb; u32 offset; skb = tcp_recv_skb(sk, tcp_sk(sk)->copied_seq, &offset); if (skb) tcp_zerocopy_set_hint_for_skb(sk, zc, skb, offset); } return 0; } static int tcp_copy_straggler_data(struct tcp_zerocopy_receive *zc, struct sk_buff *skb, u32 copylen, u32 *offset, u32 *seq) { unsigned long copy_address = (unsigned long)zc->copybuf_address; struct msghdr msg = {}; struct iovec iov; int err; if (copy_address != zc->copybuf_address) return -EINVAL; err = import_single_range(ITER_DEST, (void __user *)copy_address, copylen, &iov, &msg.msg_iter); if (err) return err; err = skb_copy_datagram_msg(skb, *offset, &msg, copylen); if (err) return err; zc->recv_skip_hint -= copylen; *offset += copylen; *seq += copylen; return (__s32)copylen; } static int tcp_zc_handle_leftover(struct tcp_zerocopy_receive *zc, struct sock *sk, struct sk_buff *skb, u32 *seq, s32 copybuf_len, struct scm_timestamping_internal *tss) { u32 offset, copylen = min_t(u32, copybuf_len, zc->recv_skip_hint); if (!copylen) return 0; /* skb is null if inq < PAGE_SIZE. */ if (skb) { offset = *seq - TCP_SKB_CB(skb)->seq; } else { skb = tcp_recv_skb(sk, *seq, &offset); if (TCP_SKB_CB(skb)->has_rxtstamp) { tcp_update_recv_tstamps(skb, tss); zc->msg_flags |= TCP_CMSG_TS; } } zc->copybuf_len = tcp_copy_straggler_data(zc, skb, copylen, &offset, seq); return zc->copybuf_len < 0 ? 0 : copylen; } static int tcp_zerocopy_vm_insert_batch_error(struct vm_area_struct *vma, struct page **pending_pages, unsigned long pages_remaining, unsigned long *address, u32 *length, u32 *seq, struct tcp_zerocopy_receive *zc, u32 total_bytes_to_map, int err) { /* At least one page did not map. Try zapping if we skipped earlier. */ if (err == -EBUSY && zc->flags & TCP_RECEIVE_ZEROCOPY_FLAG_TLB_CLEAN_HINT) { u32 maybe_zap_len; maybe_zap_len = total_bytes_to_map - /* All bytes to map */ *length + /* Mapped or pending */ (pages_remaining * PAGE_SIZE); /* Failed map. */ zap_page_range_single(vma, *address, maybe_zap_len, NULL); err = 0; } if (!err) { unsigned long leftover_pages = pages_remaining; int bytes_mapped; /* We called zap_page_range_single, try to reinsert. */ err = vm_insert_pages(vma, *address, pending_pages, &pages_remaining); bytes_mapped = PAGE_SIZE * (leftover_pages - pages_remaining); *seq += bytes_mapped; *address += bytes_mapped; } if (err) { /* Either we were unable to zap, OR we zapped, retried an * insert, and still had an issue. Either ways, pages_remaining * is the number of pages we were unable to map, and we unroll * some state we speculatively touched before. */ const int bytes_not_mapped = PAGE_SIZE * pages_remaining; *length -= bytes_not_mapped; zc->recv_skip_hint += bytes_not_mapped; } return err; } static int tcp_zerocopy_vm_insert_batch(struct vm_area_struct *vma, struct page **pages, unsigned int pages_to_map, unsigned long *address, u32 *length, u32 *seq, struct tcp_zerocopy_receive *zc, u32 total_bytes_to_map) { unsigned long pages_remaining = pages_to_map; unsigned int pages_mapped; unsigned int bytes_mapped; int err; err = vm_insert_pages(vma, *address, pages, &pages_remaining); pages_mapped = pages_to_map - (unsigned int)pages_remaining; bytes_mapped = PAGE_SIZE * pages_mapped; /* Even if vm_insert_pages fails, it may have partially succeeded in * mapping (some but not all of the pages). */ *seq += bytes_mapped; *address += bytes_mapped; if (likely(!err)) return 0; /* Error: maybe zap and retry + rollback state for failed inserts. */ return tcp_zerocopy_vm_insert_batch_error(vma, pages + pages_mapped, pages_remaining, address, length, seq, zc, total_bytes_to_map, err); } #define TCP_VALID_ZC_MSG_FLAGS (TCP_CMSG_TS) static void tcp_zc_finalize_rx_tstamp(struct sock *sk, struct tcp_zerocopy_receive *zc, struct scm_timestamping_internal *tss) { unsigned long msg_control_addr; struct msghdr cmsg_dummy; msg_control_addr = (unsigned long)zc->msg_control; cmsg_dummy.msg_control_user = (void __user *)msg_control_addr; cmsg_dummy.msg_controllen = (__kernel_size_t)zc->msg_controllen; cmsg_dummy.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0; cmsg_dummy.msg_control_is_user = true; zc->msg_flags = 0; if (zc->msg_control == msg_control_addr && zc->msg_controllen == cmsg_dummy.msg_controllen) { tcp_recv_timestamp(&cmsg_dummy, sk, tss); zc->msg_control = (__u64) ((uintptr_t)cmsg_dummy.msg_control_user); zc->msg_controllen = (__u64)cmsg_dummy.msg_controllen; zc->msg_flags = (__u32)cmsg_dummy.msg_flags; } } static struct vm_area_struct *find_tcp_vma(struct mm_struct *mm, unsigned long address, bool *mmap_locked) { struct vm_area_struct *vma = lock_vma_under_rcu(mm, address); if (vma) { if (vma->vm_ops != &tcp_vm_ops) { vma_end_read(vma); return NULL; } *mmap_locked = false; return vma; } mmap_read_lock(mm); vma = vma_lookup(mm, address); if (!vma || vma->vm_ops != &tcp_vm_ops) { mmap_read_unlock(mm); return NULL; } *mmap_locked = true; return vma; } #define TCP_ZEROCOPY_PAGE_BATCH_SIZE 32 static int tcp_zerocopy_receive(struct sock *sk, struct tcp_zerocopy_receive *zc, struct scm_timestamping_internal *tss) { u32 length = 0, offset, vma_len, avail_len, copylen = 0; unsigned long address = (unsigned long)zc->address; struct page *pages[TCP_ZEROCOPY_PAGE_BATCH_SIZE]; s32 copybuf_len = zc->copybuf_len; struct tcp_sock *tp = tcp_sk(sk); const skb_frag_t *frags = NULL; unsigned int pages_to_map = 0; struct vm_area_struct *vma; struct sk_buff *skb = NULL; u32 seq = tp->copied_seq; u32 total_bytes_to_map; int inq = tcp_inq(sk); bool mmap_locked; int ret; zc->copybuf_len = 0; zc->msg_flags = 0; if (address & (PAGE_SIZE - 1) || address != zc->address) return -EINVAL; if (sk->sk_state == TCP_LISTEN) return -ENOTCONN; sock_rps_record_flow(sk); if (inq && inq <= copybuf_len) return receive_fallback_to_copy(sk, zc, inq, tss); if (inq < PAGE_SIZE) { zc->length = 0; zc->recv_skip_hint = inq; if (!inq && sock_flag(sk, SOCK_DONE)) return -EIO; return 0; } vma = find_tcp_vma(current->mm, address, &mmap_locked); if (!vma) return -EINVAL; vma_len = min_t(unsigned long, zc->length, vma->vm_end - address); avail_len = min_t(u32, vma_len, inq); total_bytes_to_map = avail_len & ~(PAGE_SIZE - 1); if (total_bytes_to_map) { if (!(zc->flags & TCP_RECEIVE_ZEROCOPY_FLAG_TLB_CLEAN_HINT)) zap_page_range_single(vma, address, total_bytes_to_map, NULL); zc->length = total_bytes_to_map; zc->recv_skip_hint = 0; } else { zc->length = avail_len; zc->recv_skip_hint = avail_len; } ret = 0; while (length + PAGE_SIZE <= zc->length) { int mappable_offset; struct page *page; if (zc->recv_skip_hint < PAGE_SIZE) { u32 offset_frag; if (skb) { if (zc->recv_skip_hint > 0) break; skb = skb->next; offset = seq - TCP_SKB_CB(skb)->seq; } else { skb = tcp_recv_skb(sk, seq, &offset); } if (TCP_SKB_CB(skb)->has_rxtstamp) { tcp_update_recv_tstamps(skb, tss); zc->msg_flags |= TCP_CMSG_TS; } zc->recv_skip_hint = skb->len - offset; frags = skb_advance_to_frag(skb, offset, &offset_frag); if (!frags || offset_frag) break; } mappable_offset = find_next_mappable_frag(frags, zc->recv_skip_hint); if (mappable_offset) { zc->recv_skip_hint = mappable_offset; break; } page = skb_frag_page(frags); prefetchw(page); pages[pages_to_map++] = page; length += PAGE_SIZE; zc->recv_skip_hint -= PAGE_SIZE; frags++; if (pages_to_map == TCP_ZEROCOPY_PAGE_BATCH_SIZE || zc->recv_skip_hint < PAGE_SIZE) { /* Either full batch, or we're about to go to next skb * (and we cannot unroll failed ops across skbs). */ ret = tcp_zerocopy_vm_insert_batch(vma, pages, pages_to_map, &address, &length, &seq, zc, total_bytes_to_map); if (ret) goto out; pages_to_map = 0; } } if (pages_to_map) { ret = tcp_zerocopy_vm_insert_batch(vma, pages, pages_to_map, &address, &length, &seq, zc, total_bytes_to_map); } out: if (mmap_locked) mmap_read_unlock(current->mm); else vma_end_read(vma); /* Try to copy straggler data. */ if (!ret) copylen = tcp_zc_handle_leftover(zc, sk, skb, &seq, copybuf_len, tss); if (length + copylen) { WRITE_ONCE(tp->copied_seq, seq); tcp_rcv_space_adjust(sk); /* Clean up data we have read: This will do ACK frames. */ tcp_recv_skb(sk, seq, &offset); tcp_cleanup_rbuf(sk, length + copylen); ret = 0; if (length == zc->length) zc->recv_skip_hint = 0; } else { if (!zc->recv_skip_hint && sock_flag(sk, SOCK_DONE)) ret = -EIO; } zc->length = length; return ret; } #endif /* Similar to __sock_recv_timestamp, but does not require an skb */ void tcp_recv_timestamp(struct msghdr *msg, const struct sock *sk, struct scm_timestamping_internal *tss) { int new_tstamp = sock_flag(sk, SOCK_TSTAMP_NEW); bool has_timestamping = false; if (tss->ts[0].tv_sec || tss->ts[0].tv_nsec) { if (sock_flag(sk, SOCK_RCVTSTAMP)) { if (sock_flag(sk, SOCK_RCVTSTAMPNS)) { if (new_tstamp) { struct __kernel_timespec kts = { .tv_sec = tss->ts[0].tv_sec, .tv_nsec = tss->ts[0].tv_nsec, }; put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_NEW, sizeof(kts), &kts); } else { struct __kernel_old_timespec ts_old = { .tv_sec = tss->ts[0].tv_sec, .tv_nsec = tss->ts[0].tv_nsec, }; put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_OLD, sizeof(ts_old), &ts_old); } } else { if (new_tstamp) { struct __kernel_sock_timeval stv = { .tv_sec = tss->ts[0].tv_sec, .tv_usec = tss->ts[0].tv_nsec / 1000, }; put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_NEW, sizeof(stv), &stv); } else { struct __kernel_old_timeval tv = { .tv_sec = tss->ts[0].tv_sec, .tv_usec = tss->ts[0].tv_nsec / 1000, }; put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_OLD, sizeof(tv), &tv); } } } if (READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_SOFTWARE) has_timestamping = true; else tss->ts[0] = (struct timespec64) {0}; } if (tss->ts[2].tv_sec || tss->ts[2].tv_nsec) { if (READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_RAW_HARDWARE) has_timestamping = true; else tss->ts[2] = (struct timespec64) {0}; } if (has_timestamping) { tss->ts[1] = (struct timespec64) {0}; if (sock_flag(sk, SOCK_TSTAMP_NEW)) put_cmsg_scm_timestamping64(msg, tss); else put_cmsg_scm_timestamping(msg, tss); } } static int tcp_inq_hint(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); u32 copied_seq = READ_ONCE(tp->copied_seq); u32 rcv_nxt = READ_ONCE(tp->rcv_nxt); int inq; inq = rcv_nxt - copied_seq; if (unlikely(inq < 0 || copied_seq != READ_ONCE(tp->copied_seq))) { lock_sock(sk); inq = tp->rcv_nxt - tp->copied_seq; release_sock(sk); } /* After receiving a FIN, tell the user-space to continue reading * by returning a non-zero inq. */ if (inq == 0 && sock_flag(sk, SOCK_DONE)) inq = 1; return inq; } /* * This routine copies from a sock struct into the user buffer. * * Technical note: in 2.3 we work on _locked_ socket, so that * tricks with *seq access order and skb->users are not required. * Probably, code can be easily improved even more. */ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len, int flags, struct scm_timestamping_internal *tss, int *cmsg_flags) { struct tcp_sock *tp = tcp_sk(sk); int copied = 0; u32 peek_seq; u32 *seq; unsigned long used; int err; int target; /* Read at least this many bytes */ long timeo; struct sk_buff *skb, *last; u32 urg_hole = 0; err = -ENOTCONN; if (sk->sk_state == TCP_LISTEN) goto out; if (tp->recvmsg_inq) { *cmsg_flags = TCP_CMSG_INQ; msg->msg_get_inq = 1; } timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); /* Urgent data needs to be handled specially. */ if (flags & MSG_OOB) goto recv_urg; if (unlikely(tp->repair)) { err = -EPERM; if (!(flags & MSG_PEEK)) goto out; if (tp->repair_queue == TCP_SEND_QUEUE) goto recv_sndq; err = -EINVAL; if (tp->repair_queue == TCP_NO_QUEUE) goto out; /* 'common' recv queue MSG_PEEK-ing */ } seq = &tp->copied_seq; if (flags & MSG_PEEK) { peek_seq = tp->copied_seq; seq = &peek_seq; } target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); do { u32 offset; /* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */ if (unlikely(tp->urg_data) && tp->urg_seq == *seq) { if (copied) break; if (signal_pending(current)) { copied = timeo ? sock_intr_errno(timeo) : -EAGAIN; break; } } /* Next get a buffer. */ last = skb_peek_tail(&sk->sk_receive_queue); skb_queue_walk(&sk->sk_receive_queue, skb) { last = skb; /* Now that we have two receive queues this * shouldn't happen. */ if (WARN(before(*seq, TCP_SKB_CB(skb)->seq), "TCP recvmsg seq # bug: copied %X, seq %X, rcvnxt %X, fl %X\n", *seq, TCP_SKB_CB(skb)->seq, tp->rcv_nxt, flags)) break; offset = *seq - TCP_SKB_CB(skb)->seq; if (unlikely(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) { pr_err_once("%s: found a SYN, please report !\n", __func__); offset--; } if (offset < skb->len) goto found_ok_skb; if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) goto found_fin_ok; WARN(!(flags & MSG_PEEK), "TCP recvmsg seq # bug 2: copied %X, seq %X, rcvnxt %X, fl %X\n", *seq, TCP_SKB_CB(skb)->seq, tp->rcv_nxt, flags); } /* Well, if we have backlog, try to process it now yet. */ if (copied >= target && !READ_ONCE(sk->sk_backlog.tail)) break; if (copied) { if (!timeo || sk->sk_err || sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN) || signal_pending(current)) break; } else { if (sock_flag(sk, SOCK_DONE)) break; if (sk->sk_err) { copied = sock_error(sk); break; } if (sk->sk_shutdown & RCV_SHUTDOWN) break; if (sk->sk_state == TCP_CLOSE) { /* This occurs when user tries to read * from never connected socket. */ copied = -ENOTCONN; break; } if (!timeo) { copied = -EAGAIN; break; } if (signal_pending(current)) { copied = sock_intr_errno(timeo); break; } } if (copied >= target) { /* Do not sleep, just process backlog. */ __sk_flush_backlog(sk); } else { tcp_cleanup_rbuf(sk, copied); sk_wait_data(sk, &timeo, last); } if ((flags & MSG_PEEK) && (peek_seq - copied - urg_hole != tp->copied_seq)) { net_dbg_ratelimited("TCP(%s:%d): Application bug, race in MSG_PEEK\n", current->comm, task_pid_nr(current)); peek_seq = tp->copied_seq; } continue; found_ok_skb: /* Ok so how much can we use? */ used = skb->len - offset; if (len < used) used = len; /* Do we have urgent data here? */ if (unlikely(tp->urg_data)) { u32 urg_offset = tp->urg_seq - *seq; if (urg_offset < used) { if (!urg_offset) { if (!sock_flag(sk, SOCK_URGINLINE)) { WRITE_ONCE(*seq, *seq + 1); urg_hole++; offset++; used--; if (!used) goto skip_copy; } } else used = urg_offset; } } if (!(flags & MSG_TRUNC)) { err = skb_copy_datagram_msg(skb, offset, msg, used); if (err) { /* Exception. Bailout! */ if (!copied) copied = -EFAULT; break; } } WRITE_ONCE(*seq, *seq + used); copied += used; len -= used; tcp_rcv_space_adjust(sk); skip_copy: if (unlikely(tp->urg_data) && after(tp->copied_seq, tp->urg_seq)) { WRITE_ONCE(tp->urg_data, 0); tcp_fast_path_check(sk); } if (TCP_SKB_CB(skb)->has_rxtstamp) { tcp_update_recv_tstamps(skb, tss); *cmsg_flags |= TCP_CMSG_TS; } if (used + offset < skb->len) continue; if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) goto found_fin_ok; if (!(flags & MSG_PEEK)) tcp_eat_recv_skb(sk, skb); continue; found_fin_ok: /* Process the FIN. */ WRITE_ONCE(*seq, *seq + 1); if (!(flags & MSG_PEEK)) tcp_eat_recv_skb(sk, skb); break; } while (len > 0); /* According to UNIX98, msg_name/msg_namelen are ignored * on connected socket. I was just happy when found this 8) --ANK */ /* Clean up data we have read: This will do ACK frames. */ tcp_cleanup_rbuf(sk, copied); return copied; out: return err; recv_urg: err = tcp_recv_urg(sk, msg, len, flags); goto out; recv_sndq: err = tcp_peek_sndq(sk, msg, len); goto out; } int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { int cmsg_flags = 0, ret; struct scm_timestamping_internal tss; if (unlikely(flags & MSG_ERRQUEUE)) return inet_recv_error(sk, msg, len, addr_len); if (sk_can_busy_loop(sk) && skb_queue_empty_lockless(&sk->sk_receive_queue) && sk->sk_state == TCP_ESTABLISHED) sk_busy_loop(sk, flags & MSG_DONTWAIT); lock_sock(sk); ret = tcp_recvmsg_locked(sk, msg, len, flags, &tss, &cmsg_flags); release_sock(sk); if ((cmsg_flags || msg->msg_get_inq) && ret >= 0) { if (cmsg_flags & TCP_CMSG_TS) tcp_recv_timestamp(msg, sk, &tss); if (msg->msg_get_inq) { msg->msg_inq = tcp_inq_hint(sk); if (cmsg_flags & TCP_CMSG_INQ) put_cmsg(msg, SOL_TCP, TCP_CM_INQ, sizeof(msg->msg_inq), &msg->msg_inq); } } return ret; } EXPORT_SYMBOL(tcp_recvmsg); void tcp_set_state(struct sock *sk, int state) { int oldstate = sk->sk_state; /* We defined a new enum for TCP states that are exported in BPF * so as not force the internal TCP states to be frozen. The * following checks will detect if an internal state value ever * differs from the BPF value. If this ever happens, then we will * need to remap the internal value to the BPF value before calling * tcp_call_bpf_2arg. */ BUILD_BUG_ON((int)BPF_TCP_ESTABLISHED != (int)TCP_ESTABLISHED); BUILD_BUG_ON((int)BPF_TCP_SYN_SENT != (int)TCP_SYN_SENT); BUILD_BUG_ON((int)BPF_TCP_SYN_RECV != (int)TCP_SYN_RECV); BUILD_BUG_ON((int)BPF_TCP_FIN_WAIT1 != (int)TCP_FIN_WAIT1); BUILD_BUG_ON((int)BPF_TCP_FIN_WAIT2 != (int)TCP_FIN_WAIT2); BUILD_BUG_ON((int)BPF_TCP_TIME_WAIT != (int)TCP_TIME_WAIT); BUILD_BUG_ON((int)BPF_TCP_CLOSE != (int)TCP_CLOSE); BUILD_BUG_ON((int)BPF_TCP_CLOSE_WAIT != (int)TCP_CLOSE_WAIT); BUILD_BUG_ON((int)BPF_TCP_LAST_ACK != (int)TCP_LAST_ACK); BUILD_BUG_ON((int)BPF_TCP_LISTEN != (int)TCP_LISTEN); BUILD_BUG_ON((int)BPF_TCP_CLOSING != (int)TCP_CLOSING); BUILD_BUG_ON((int)BPF_TCP_NEW_SYN_RECV != (int)TCP_NEW_SYN_RECV); BUILD_BUG_ON((int)BPF_TCP_MAX_STATES != (int)TCP_MAX_STATES); /* bpf uapi header bpf.h defines an anonymous enum with values * BPF_TCP_* used by bpf programs. Currently gcc built vmlinux * is able to emit this enum in DWARF due to the above BUILD_BUG_ON. * But clang built vmlinux does not have this enum in DWARF * since clang removes the above code before generating IR/debuginfo. * Let us explicitly emit the type debuginfo to ensure the * above-mentioned anonymous enum in the vmlinux DWARF and hence BTF * regardless of which compiler is used. */ BTF_TYPE_EMIT_ENUM(BPF_TCP_ESTABLISHED); if (BPF_SOCK_OPS_TEST_FLAG(tcp_sk(sk), BPF_SOCK_OPS_STATE_CB_FLAG)) tcp_call_bpf_2arg(sk, BPF_SOCK_OPS_STATE_CB, oldstate, state); switch (state) { case TCP_ESTABLISHED: if (oldstate != TCP_ESTABLISHED) TCP_INC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); break; case TCP_CLOSE: if (oldstate == TCP_CLOSE_WAIT || oldstate == TCP_ESTABLISHED) TCP_INC_STATS(sock_net(sk), TCP_MIB_ESTABRESETS); sk->sk_prot->unhash(sk); if (inet_csk(sk)->icsk_bind_hash && !(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) inet_put_port(sk); fallthrough; default: if (oldstate == TCP_ESTABLISHED) TCP_DEC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); } /* Change state AFTER socket is unhashed to avoid closed * socket sitting in hash tables. */ inet_sk_state_store(sk, state); } EXPORT_SYMBOL_GPL(tcp_set_state); /* * State processing on a close. This implements the state shift for * sending our FIN frame. Note that we only send a FIN for some * states. A shutdown() may have already sent the FIN, or we may be * closed. */ static const unsigned char new_state[16] = { /* current state: new state: action: */ [0 /* (Invalid) */] = TCP_CLOSE, [TCP_ESTABLISHED] = TCP_FIN_WAIT1 | TCP_ACTION_FIN, [TCP_SYN_SENT] = TCP_CLOSE, [TCP_SYN_RECV] = TCP_FIN_WAIT1 | TCP_ACTION_FIN, [TCP_FIN_WAIT1] = TCP_FIN_WAIT1, [TCP_FIN_WAIT2] = TCP_FIN_WAIT2, [TCP_TIME_WAIT] = TCP_CLOSE, [TCP_CLOSE] = TCP_CLOSE, [TCP_CLOSE_WAIT] = TCP_LAST_ACK | TCP_ACTION_FIN, [TCP_LAST_ACK] = TCP_LAST_ACK, [TCP_LISTEN] = TCP_CLOSE, [TCP_CLOSING] = TCP_CLOSING, [TCP_NEW_SYN_RECV] = TCP_CLOSE, /* should not happen ! */ }; static int tcp_close_state(struct sock *sk) { int next = (int)new_state[sk->sk_state]; int ns = next & TCP_STATE_MASK; tcp_set_state(sk, ns); return next & TCP_ACTION_FIN; } /* * Shutdown the sending side of a connection. Much like close except * that we don't receive shut down or sock_set_flag(sk, SOCK_DEAD). */ void tcp_shutdown(struct sock *sk, int how) { /* We need to grab some memory, and put together a FIN, * and then put it into the queue to be sent. * Tim MacKenzie([email protected]) 4 Dec '92. */ if (!(how & SEND_SHUTDOWN)) return; /* If we've already sent a FIN, or it's a closed state, skip this. */ if ((1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE_WAIT)) { /* Clear out any half completed packets. FIN if needed. */ if (tcp_close_state(sk)) tcp_send_fin(sk); } } EXPORT_SYMBOL(tcp_shutdown); int tcp_orphan_count_sum(void) { int i, total = 0; for_each_possible_cpu(i) total += per_cpu(tcp_orphan_count, i); return max(total, 0); } static int tcp_orphan_cache; static struct timer_list tcp_orphan_timer; #define TCP_ORPHAN_TIMER_PERIOD msecs_to_jiffies(100) static void tcp_orphan_update(struct timer_list *unused) { WRITE_ONCE(tcp_orphan_cache, tcp_orphan_count_sum()); mod_timer(&tcp_orphan_timer, jiffies + TCP_ORPHAN_TIMER_PERIOD); } static bool tcp_too_many_orphans(int shift) { return READ_ONCE(tcp_orphan_cache) << shift > READ_ONCE(sysctl_tcp_max_orphans); } bool tcp_check_oom(struct sock *sk, int shift) { bool too_many_orphans, out_of_socket_memory; too_many_orphans = tcp_too_many_orphans(shift); out_of_socket_memory = tcp_out_of_memory(sk); if (too_many_orphans) net_info_ratelimited("too many orphaned sockets\n"); if (out_of_socket_memory) net_info_ratelimited("out of memory -- consider tuning tcp_mem\n"); return too_many_orphans || out_of_socket_memory; } void __tcp_close(struct sock *sk, long timeout) { struct sk_buff *skb; int data_was_unread = 0; int state; WRITE_ONCE(sk->sk_shutdown, SHUTDOWN_MASK); if (sk->sk_state == TCP_LISTEN) { tcp_set_state(sk, TCP_CLOSE); /* Special case. */ inet_csk_listen_stop(sk); goto adjudge_to_death; } /* We need to flush the recv. buffs. We do this only on the * descriptor close, not protocol-sourced closes, because the * reader process may not have drained the data yet! */ while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) { u32 len = TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq; if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) len--; data_was_unread += len; __kfree_skb(skb); } /* If socket has been already reset (e.g. in tcp_reset()) - kill it. */ if (sk->sk_state == TCP_CLOSE) goto adjudge_to_death; /* As outlined in RFC 2525, section 2.17, we send a RST here because * data was lost. To witness the awful effects of the old behavior of * always doing a FIN, run an older 2.1.x kernel or 2.0.x, start a bulk * GET in an FTP client, suspend the process, wait for the client to * advertise a zero window, then kill -9 the FTP client, wheee... * Note: timeout is always zero in such a case. */ if (unlikely(tcp_sk(sk)->repair)) { sk->sk_prot->disconnect(sk, 0); } else if (data_was_unread) { /* Unread data was tossed, zap the connection. */ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONCLOSE); tcp_set_state(sk, TCP_CLOSE); tcp_send_active_reset(sk, sk->sk_allocation); } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) { /* Check zero linger _after_ checking for unread data. */ sk->sk_prot->disconnect(sk, 0); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA); } else if (tcp_close_state(sk)) { /* We FIN if the application ate all the data before * zapping the connection. */ /* RED-PEN. Formally speaking, we have broken TCP state * machine. State transitions: * * TCP_ESTABLISHED -> TCP_FIN_WAIT1 * TCP_SYN_RECV -> TCP_FIN_WAIT1 (forget it, it's impossible) * TCP_CLOSE_WAIT -> TCP_LAST_ACK * * are legal only when FIN has been sent (i.e. in window), * rather than queued out of window. Purists blame. * * F.e. "RFC state" is ESTABLISHED, * if Linux state is FIN-WAIT-1, but FIN is still not sent. * * The visible declinations are that sometimes * we enter time-wait state, when it is not required really * (harmless), do not send active resets, when they are * required by specs (TCP_ESTABLISHED, TCP_CLOSE_WAIT, when * they look as CLOSING or LAST_ACK for Linux) * Probably, I missed some more holelets. * --ANK * XXX (TFO) - To start off we don't support SYN+ACK+FIN * in a single packet! (May consider it later but will * probably need API support or TCP_CORK SYN-ACK until * data is written and socket is closed.) */ tcp_send_fin(sk); } sk_stream_wait_close(sk, timeout); adjudge_to_death: state = sk->sk_state; sock_hold(sk); sock_orphan(sk); local_bh_disable(); bh_lock_sock(sk); /* remove backlog if any, without releasing ownership. */ __release_sock(sk); this_cpu_inc(tcp_orphan_count); /* Have we already been destroyed by a softirq or backlog? */ if (state != TCP_CLOSE && sk->sk_state == TCP_CLOSE) goto out; /* This is a (useful) BSD violating of the RFC. There is a * problem with TCP as specified in that the other end could * keep a socket open forever with no application left this end. * We use a 1 minute timeout (about the same as BSD) then kill * our end. If they send after that then tough - BUT: long enough * that we won't make the old 4*rto = almost no time - whoops * reset mistake. * * Nope, it was not mistake. It is really desired behaviour * f.e. on http servers, when such sockets are useless, but * consume significant resources. Let's do it with special * linger2 option. --ANK */ if (sk->sk_state == TCP_FIN_WAIT2) { struct tcp_sock *tp = tcp_sk(sk); if (READ_ONCE(tp->linger2) < 0) { tcp_set_state(sk, TCP_CLOSE); tcp_send_active_reset(sk, GFP_ATOMIC); __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONLINGER); } else { const int tmo = tcp_fin_time(sk); if (tmo > TCP_TIMEWAIT_LEN) { inet_csk_reset_keepalive_timer(sk, tmo - TCP_TIMEWAIT_LEN); } else { tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); goto out; } } } if (sk->sk_state != TCP_CLOSE) { if (tcp_check_oom(sk, 0)) { tcp_set_state(sk, TCP_CLOSE); tcp_send_active_reset(sk, GFP_ATOMIC); __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONMEMORY); } else if (!check_net(sock_net(sk))) { /* Not possible to send reset; just close */ tcp_set_state(sk, TCP_CLOSE); } } if (sk->sk_state == TCP_CLOSE) { struct request_sock *req; req = rcu_dereference_protected(tcp_sk(sk)->fastopen_rsk, lockdep_sock_is_held(sk)); /* We could get here with a non-NULL req if the socket is * aborted (e.g., closed with unread data) before 3WHS * finishes. */ if (req) reqsk_fastopen_remove(sk, req, false); inet_csk_destroy_sock(sk); } /* Otherwise, socket is reprieved until protocol close. */ out: bh_unlock_sock(sk); local_bh_enable(); } void tcp_close(struct sock *sk, long timeout) { lock_sock(sk); __tcp_close(sk, timeout); release_sock(sk); sock_put(sk); } EXPORT_SYMBOL(tcp_close); /* These states need RST on ABORT according to RFC793 */ static inline bool tcp_need_reset(int state) { return (1 << state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_SYN_RECV); } static void tcp_rtx_queue_purge(struct sock *sk) { struct rb_node *p = rb_first(&sk->tcp_rtx_queue); tcp_sk(sk)->highest_sack = NULL; while (p) { struct sk_buff *skb = rb_to_skb(p); p = rb_next(p); /* Since we are deleting whole queue, no need to * list_del(&skb->tcp_tsorted_anchor) */ tcp_rtx_queue_unlink(skb, sk); tcp_wmem_free_skb(sk, skb); } } void tcp_write_queue_purge(struct sock *sk) { struct sk_buff *skb; tcp_chrono_stop(sk, TCP_CHRONO_BUSY); while ((skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) { tcp_skb_tsorted_anchor_cleanup(skb); tcp_wmem_free_skb(sk, skb); } tcp_rtx_queue_purge(sk); INIT_LIST_HEAD(&tcp_sk(sk)->tsorted_sent_queue); tcp_clear_all_retrans_hints(tcp_sk(sk)); tcp_sk(sk)->packets_out = 0; inet_csk(sk)->icsk_backoff = 0; } int tcp_disconnect(struct sock *sk, int flags) { struct inet_sock *inet = inet_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); int old_state = sk->sk_state; u32 seq; /* Deny disconnect if other threads are blocked in sk_wait_event() * or inet_wait_for_connect(). */ if (sk->sk_wait_pending) return -EBUSY; if (old_state != TCP_CLOSE) tcp_set_state(sk, TCP_CLOSE); /* ABORT function of RFC793 */ if (old_state == TCP_LISTEN) { inet_csk_listen_stop(sk); } else if (unlikely(tp->repair)) { WRITE_ONCE(sk->sk_err, ECONNABORTED); } else if (tcp_need_reset(old_state) || (tp->snd_nxt != tp->write_seq && (1 << old_state) & (TCPF_CLOSING | TCPF_LAST_ACK))) { /* The last check adjusts for discrepancy of Linux wrt. RFC * states */ tcp_send_active_reset(sk, gfp_any()); WRITE_ONCE(sk->sk_err, ECONNRESET); } else if (old_state == TCP_SYN_SENT) WRITE_ONCE(sk->sk_err, ECONNRESET); tcp_clear_xmit_timers(sk); __skb_queue_purge(&sk->sk_receive_queue); WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); WRITE_ONCE(tp->urg_data, 0); tcp_write_queue_purge(sk); tcp_fastopen_active_disable_ofo_check(sk); skb_rbtree_purge(&tp->out_of_order_queue); inet->inet_dport = 0; inet_bhash2_reset_saddr(sk); WRITE_ONCE(sk->sk_shutdown, 0); sock_reset_flag(sk, SOCK_DONE); tp->srtt_us = 0; tp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT); tp->rcv_rtt_last_tsecr = 0; seq = tp->write_seq + tp->max_window + 2; if (!seq) seq = 1; WRITE_ONCE(tp->write_seq, seq); icsk->icsk_backoff = 0; icsk->icsk_probes_out = 0; icsk->icsk_probes_tstamp = 0; icsk->icsk_rto = TCP_TIMEOUT_INIT; icsk->icsk_rto_min = TCP_RTO_MIN; icsk->icsk_delack_max = TCP_DELACK_MAX; tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tcp_snd_cwnd_set(tp, TCP_INIT_CWND); tp->snd_cwnd_cnt = 0; tp->is_cwnd_limited = 0; tp->max_packets_out = 0; tp->window_clamp = 0; tp->delivered = 0; tp->delivered_ce = 0; if (icsk->icsk_ca_ops->release) icsk->icsk_ca_ops->release(sk); memset(icsk->icsk_ca_priv, 0, sizeof(icsk->icsk_ca_priv)); icsk->icsk_ca_initialized = 0; tcp_set_ca_state(sk, TCP_CA_Open); tp->is_sack_reneg = 0; tcp_clear_retrans(tp); tp->total_retrans = 0; inet_csk_delack_init(sk); /* Initialize rcv_mss to TCP_MIN_MSS to avoid division by 0 * issue in __tcp_select_window() */ icsk->icsk_ack.rcv_mss = TCP_MIN_MSS; memset(&tp->rx_opt, 0, sizeof(tp->rx_opt)); __sk_dst_reset(sk); dst_release(xchg((__force struct dst_entry **)&sk->sk_rx_dst, NULL)); tcp_saved_syn_free(tp); tp->compressed_ack = 0; tp->segs_in = 0; tp->segs_out = 0; tp->bytes_sent = 0; tp->bytes_acked = 0; tp->bytes_received = 0; tp->bytes_retrans = 0; tp->data_segs_in = 0; tp->data_segs_out = 0; tp->duplicate_sack[0].start_seq = 0; tp->duplicate_sack[0].end_seq = 0; tp->dsack_dups = 0; tp->reord_seen = 0; tp->retrans_out = 0; tp->sacked_out = 0; tp->tlp_high_seq = 0; tp->last_oow_ack_time = 0; tp->plb_rehash = 0; /* There's a bubble in the pipe until at least the first ACK. */ tp->app_limited = ~0U; tp->rate_app_limited = 1; tp->rack.mstamp = 0; tp->rack.advanced = 0; tp->rack.reo_wnd_steps = 1; tp->rack.last_delivered = 0; tp->rack.reo_wnd_persist = 0; tp->rack.dsack_seen = 0; tp->syn_data_acked = 0; tp->rx_opt.saw_tstamp = 0; tp->rx_opt.dsack = 0; tp->rx_opt.num_sacks = 0; tp->rcv_ooopack = 0; /* Clean up fastopen related fields */ tcp_free_fastopen_req(tp); inet_clear_bit(DEFER_CONNECT, sk); tp->fastopen_client_fail = 0; WARN_ON(inet->inet_num && !icsk->icsk_bind_hash); if (sk->sk_frag.page) { put_page(sk->sk_frag.page); sk->sk_frag.page = NULL; sk->sk_frag.offset = 0; } sk_error_report(sk); return 0; } EXPORT_SYMBOL(tcp_disconnect); static inline bool tcp_can_repair_sock(const struct sock *sk) { return sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN) && (sk->sk_state != TCP_LISTEN); } static int tcp_repair_set_window(struct tcp_sock *tp, sockptr_t optbuf, int len) { struct tcp_repair_window opt; if (!tp->repair) return -EPERM; if (len != sizeof(opt)) return -EINVAL; if (copy_from_sockptr(&opt, optbuf, sizeof(opt))) return -EFAULT; if (opt.max_window < opt.snd_wnd) return -EINVAL; if (after(opt.snd_wl1, tp->rcv_nxt + opt.rcv_wnd)) return -EINVAL; if (after(opt.rcv_wup, tp->rcv_nxt)) return -EINVAL; tp->snd_wl1 = opt.snd_wl1; tp->snd_wnd = opt.snd_wnd; tp->max_window = opt.max_window; tp->rcv_wnd = opt.rcv_wnd; tp->rcv_wup = opt.rcv_wup; return 0; } static int tcp_repair_options_est(struct sock *sk, sockptr_t optbuf, unsigned int len) { struct tcp_sock *tp = tcp_sk(sk); struct tcp_repair_opt opt; size_t offset = 0; while (len >= sizeof(opt)) { if (copy_from_sockptr_offset(&opt, optbuf, offset, sizeof(opt))) return -EFAULT; offset += sizeof(opt); len -= sizeof(opt); switch (opt.opt_code) { case TCPOPT_MSS: tp->rx_opt.mss_clamp = opt.opt_val; tcp_mtup_init(sk); break; case TCPOPT_WINDOW: { u16 snd_wscale = opt.opt_val & 0xFFFF; u16 rcv_wscale = opt.opt_val >> 16; if (snd_wscale > TCP_MAX_WSCALE || rcv_wscale > TCP_MAX_WSCALE) return -EFBIG; tp->rx_opt.snd_wscale = snd_wscale; tp->rx_opt.rcv_wscale = rcv_wscale; tp->rx_opt.wscale_ok = 1; } break; case TCPOPT_SACK_PERM: if (opt.opt_val != 0) return -EINVAL; tp->rx_opt.sack_ok |= TCP_SACK_SEEN; break; case TCPOPT_TIMESTAMP: if (opt.opt_val != 0) return -EINVAL; tp->rx_opt.tstamp_ok = 1; break; } } return 0; } DEFINE_STATIC_KEY_FALSE(tcp_tx_delay_enabled); EXPORT_SYMBOL(tcp_tx_delay_enabled); static void tcp_enable_tx_delay(void) { if (!static_branch_unlikely(&tcp_tx_delay_enabled)) { static int __tcp_tx_delay_enabled = 0; if (cmpxchg(&__tcp_tx_delay_enabled, 0, 1) == 0) { static_branch_enable(&tcp_tx_delay_enabled); pr_info("TCP_TX_DELAY enabled\n"); } } } /* When set indicates to always queue non-full frames. Later the user clears * this option and we transmit any pending partial frames in the queue. This is * meant to be used alongside sendfile() to get properly filled frames when the * user (for example) must write out headers with a write() call first and then * use sendfile to send out the data parts. * * TCP_CORK can be set together with TCP_NODELAY and it is stronger than * TCP_NODELAY. */ void __tcp_sock_set_cork(struct sock *sk, bool on) { struct tcp_sock *tp = tcp_sk(sk); if (on) { tp->nonagle |= TCP_NAGLE_CORK; } else { tp->nonagle &= ~TCP_NAGLE_CORK; if (tp->nonagle & TCP_NAGLE_OFF) tp->nonagle |= TCP_NAGLE_PUSH; tcp_push_pending_frames(sk); } } void tcp_sock_set_cork(struct sock *sk, bool on) { lock_sock(sk); __tcp_sock_set_cork(sk, on); release_sock(sk); } EXPORT_SYMBOL(tcp_sock_set_cork); /* TCP_NODELAY is weaker than TCP_CORK, so that this option on corked socket is * remembered, but it is not activated until cork is cleared. * * However, when TCP_NODELAY is set we make an explicit push, which overrides * even TCP_CORK for currently queued segments. */ void __tcp_sock_set_nodelay(struct sock *sk, bool on) { if (on) { tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF|TCP_NAGLE_PUSH; tcp_push_pending_frames(sk); } else { tcp_sk(sk)->nonagle &= ~TCP_NAGLE_OFF; } } void tcp_sock_set_nodelay(struct sock *sk) { lock_sock(sk); __tcp_sock_set_nodelay(sk, true); release_sock(sk); } EXPORT_SYMBOL(tcp_sock_set_nodelay); static void __tcp_sock_set_quickack(struct sock *sk, int val) { if (!val) { inet_csk_enter_pingpong_mode(sk); return; } inet_csk_exit_pingpong_mode(sk); if ((1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) && inet_csk_ack_scheduled(sk)) { inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_PUSHED; tcp_cleanup_rbuf(sk, 1); if (!(val & 1)) inet_csk_enter_pingpong_mode(sk); } } void tcp_sock_set_quickack(struct sock *sk, int val) { lock_sock(sk); __tcp_sock_set_quickack(sk, val); release_sock(sk); } EXPORT_SYMBOL(tcp_sock_set_quickack); int tcp_sock_set_syncnt(struct sock *sk, int val) { if (val < 1 || val > MAX_TCP_SYNCNT) return -EINVAL; WRITE_ONCE(inet_csk(sk)->icsk_syn_retries, val); return 0; } EXPORT_SYMBOL(tcp_sock_set_syncnt); int tcp_sock_set_user_timeout(struct sock *sk, int val) { /* Cap the max time in ms TCP will retry or probe the window * before giving up and aborting (ETIMEDOUT) a connection. */ if (val < 0) return -EINVAL; WRITE_ONCE(inet_csk(sk)->icsk_user_timeout, val); return 0; } EXPORT_SYMBOL(tcp_sock_set_user_timeout); int tcp_sock_set_keepidle_locked(struct sock *sk, int val) { struct tcp_sock *tp = tcp_sk(sk); if (val < 1 || val > MAX_TCP_KEEPIDLE) return -EINVAL; /* Paired with WRITE_ONCE() in keepalive_time_when() */ WRITE_ONCE(tp->keepalive_time, val * HZ); if (sock_flag(sk, SOCK_KEEPOPEN) && !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { u32 elapsed = keepalive_time_elapsed(tp); if (tp->keepalive_time > elapsed) elapsed = tp->keepalive_time - elapsed; else elapsed = 0; inet_csk_reset_keepalive_timer(sk, elapsed); } return 0; } int tcp_sock_set_keepidle(struct sock *sk, int val) { int err; lock_sock(sk); err = tcp_sock_set_keepidle_locked(sk, val); release_sock(sk); return err; } EXPORT_SYMBOL(tcp_sock_set_keepidle); int tcp_sock_set_keepintvl(struct sock *sk, int val) { if (val < 1 || val > MAX_TCP_KEEPINTVL) return -EINVAL; WRITE_ONCE(tcp_sk(sk)->keepalive_intvl, val * HZ); return 0; } EXPORT_SYMBOL(tcp_sock_set_keepintvl); int tcp_sock_set_keepcnt(struct sock *sk, int val) { if (val < 1 || val > MAX_TCP_KEEPCNT) return -EINVAL; /* Paired with READ_ONCE() in keepalive_probes() */ WRITE_ONCE(tcp_sk(sk)->keepalive_probes, val); return 0; } EXPORT_SYMBOL(tcp_sock_set_keepcnt); int tcp_set_window_clamp(struct sock *sk, int val) { struct tcp_sock *tp = tcp_sk(sk); if (!val) { if (sk->sk_state != TCP_CLOSE) return -EINVAL; tp->window_clamp = 0; } else { tp->window_clamp = val < SOCK_MIN_RCVBUF / 2 ? SOCK_MIN_RCVBUF / 2 : val; tp->rcv_ssthresh = min(tp->rcv_wnd, tp->window_clamp); } return 0; } /* * Socket option code for TCP. */ int do_tcp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); struct net *net = sock_net(sk); int val; int err = 0; /* These are data/string values, all the others are ints */ switch (optname) { case TCP_CONGESTION: { char name[TCP_CA_NAME_MAX]; if (optlen < 1) return -EINVAL; val = strncpy_from_sockptr(name, optval, min_t(long, TCP_CA_NAME_MAX-1, optlen)); if (val < 0) return -EFAULT; name[val] = 0; sockopt_lock_sock(sk); err = tcp_set_congestion_control(sk, name, !has_current_bpf_ctx(), sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)); sockopt_release_sock(sk); return err; } case TCP_ULP: { char name[TCP_ULP_NAME_MAX]; if (optlen < 1) return -EINVAL; val = strncpy_from_sockptr(name, optval, min_t(long, TCP_ULP_NAME_MAX - 1, optlen)); if (val < 0) return -EFAULT; name[val] = 0; sockopt_lock_sock(sk); err = tcp_set_ulp(sk, name); sockopt_release_sock(sk); return err; } case TCP_FASTOPEN_KEY: { __u8 key[TCP_FASTOPEN_KEY_BUF_LENGTH]; __u8 *backup_key = NULL; /* Allow a backup key as well to facilitate key rotation * First key is the active one. */ if (optlen != TCP_FASTOPEN_KEY_LENGTH && optlen != TCP_FASTOPEN_KEY_BUF_LENGTH) return -EINVAL; if (copy_from_sockptr(key, optval, optlen)) return -EFAULT; if (optlen == TCP_FASTOPEN_KEY_BUF_LENGTH) backup_key = key + TCP_FASTOPEN_KEY_LENGTH; return tcp_fastopen_reset_cipher(net, sk, key, backup_key); } default: /* fallthru */ break; } if (optlen < sizeof(int)) return -EINVAL; if (copy_from_sockptr(&val, optval, sizeof(val))) return -EFAULT; /* Handle options that can be set without locking the socket. */ switch (optname) { case TCP_SYNCNT: return tcp_sock_set_syncnt(sk, val); case TCP_USER_TIMEOUT: return tcp_sock_set_user_timeout(sk, val); case TCP_KEEPINTVL: return tcp_sock_set_keepintvl(sk, val); case TCP_KEEPCNT: return tcp_sock_set_keepcnt(sk, val); case TCP_LINGER2: if (val < 0) WRITE_ONCE(tp->linger2, -1); else if (val > TCP_FIN_TIMEOUT_MAX / HZ) WRITE_ONCE(tp->linger2, TCP_FIN_TIMEOUT_MAX); else WRITE_ONCE(tp->linger2, val * HZ); return 0; case TCP_DEFER_ACCEPT: /* Translate value in seconds to number of retransmits */ WRITE_ONCE(icsk->icsk_accept_queue.rskq_defer_accept, secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ, TCP_RTO_MAX / HZ)); return 0; } sockopt_lock_sock(sk); switch (optname) { case TCP_MAXSEG: /* Values greater than interface MTU won't take effect. However * at the point when this call is done we typically don't yet * know which interface is going to be used */ if (val && (val < TCP_MIN_MSS || val > MAX_TCP_WINDOW)) { err = -EINVAL; break; } tp->rx_opt.user_mss = val; break; case TCP_NODELAY: __tcp_sock_set_nodelay(sk, val); break; case TCP_THIN_LINEAR_TIMEOUTS: if (val < 0 || val > 1) err = -EINVAL; else tp->thin_lto = val; break; case TCP_THIN_DUPACK: if (val < 0 || val > 1) err = -EINVAL; break; case TCP_REPAIR: if (!tcp_can_repair_sock(sk)) err = -EPERM; else if (val == TCP_REPAIR_ON) { tp->repair = 1; sk->sk_reuse = SK_FORCE_REUSE; tp->repair_queue = TCP_NO_QUEUE; } else if (val == TCP_REPAIR_OFF) { tp->repair = 0; sk->sk_reuse = SK_NO_REUSE; tcp_send_window_probe(sk); } else if (val == TCP_REPAIR_OFF_NO_WP) { tp->repair = 0; sk->sk_reuse = SK_NO_REUSE; } else err = -EINVAL; break; case TCP_REPAIR_QUEUE: if (!tp->repair) err = -EPERM; else if ((unsigned int)val < TCP_QUEUES_NR) tp->repair_queue = val; else err = -EINVAL; break; case TCP_QUEUE_SEQ: if (sk->sk_state != TCP_CLOSE) { err = -EPERM; } else if (tp->repair_queue == TCP_SEND_QUEUE) { if (!tcp_rtx_queue_empty(sk)) err = -EPERM; else WRITE_ONCE(tp->write_seq, val); } else if (tp->repair_queue == TCP_RECV_QUEUE) { if (tp->rcv_nxt != tp->copied_seq) { err = -EPERM; } else { WRITE_ONCE(tp->rcv_nxt, val); WRITE_ONCE(tp->copied_seq, val); } } else { err = -EINVAL; } break; case TCP_REPAIR_OPTIONS: if (!tp->repair) err = -EINVAL; else if (sk->sk_state == TCP_ESTABLISHED && !tp->bytes_sent) err = tcp_repair_options_est(sk, optval, optlen); else err = -EPERM; break; case TCP_CORK: __tcp_sock_set_cork(sk, val); break; case TCP_KEEPIDLE: err = tcp_sock_set_keepidle_locked(sk, val); break; case TCP_SAVE_SYN: /* 0: disable, 1: enable, 2: start from ether_header */ if (val < 0 || val > 2) err = -EINVAL; else tp->save_syn = val; break; case TCP_WINDOW_CLAMP: err = tcp_set_window_clamp(sk, val); break; case TCP_QUICKACK: __tcp_sock_set_quickack(sk, val); break; #ifdef CONFIG_TCP_MD5SIG case TCP_MD5SIG: case TCP_MD5SIG_EXT: err = tp->af_specific->md5_parse(sk, optname, optval, optlen); break; #endif case TCP_FASTOPEN: if (val >= 0 && ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { tcp_fastopen_init_key_once(net); fastopen_queue_tune(sk, val); } else { err = -EINVAL; } break; case TCP_FASTOPEN_CONNECT: if (val > 1 || val < 0) { err = -EINVAL; } else if (READ_ONCE(net->ipv4.sysctl_tcp_fastopen) & TFO_CLIENT_ENABLE) { if (sk->sk_state == TCP_CLOSE) tp->fastopen_connect = val; else err = -EINVAL; } else { err = -EOPNOTSUPP; } break; case TCP_FASTOPEN_NO_COOKIE: if (val > 1 || val < 0) err = -EINVAL; else if (!((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) err = -EINVAL; else tp->fastopen_no_cookie = val; break; case TCP_TIMESTAMP: if (!tp->repair) err = -EPERM; else WRITE_ONCE(tp->tsoffset, val - tcp_time_stamp_raw()); break; case TCP_REPAIR_WINDOW: err = tcp_repair_set_window(tp, optval, optlen); break; case TCP_NOTSENT_LOWAT: WRITE_ONCE(tp->notsent_lowat, val); sk->sk_write_space(sk); break; case TCP_INQ: if (val > 1 || val < 0) err = -EINVAL; else tp->recvmsg_inq = val; break; case TCP_TX_DELAY: if (val) tcp_enable_tx_delay(); WRITE_ONCE(tp->tcp_tx_delay, val); break; default: err = -ENOPROTOOPT; break; } sockopt_release_sock(sk); return err; } int tcp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { const struct inet_connection_sock *icsk = inet_csk(sk); if (level != SOL_TCP) /* Paired with WRITE_ONCE() in do_ipv6_setsockopt() and tcp_v6_connect() */ return READ_ONCE(icsk->icsk_af_ops)->setsockopt(sk, level, optname, optval, optlen); return do_tcp_setsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(tcp_setsockopt); static void tcp_get_info_chrono_stats(const struct tcp_sock *tp, struct tcp_info *info) { u64 stats[__TCP_CHRONO_MAX], total = 0; enum tcp_chrono i; for (i = TCP_CHRONO_BUSY; i < __TCP_CHRONO_MAX; ++i) { stats[i] = tp->chrono_stat[i - 1]; if (i == tp->chrono_type) stats[i] += tcp_jiffies32 - tp->chrono_start; stats[i] *= USEC_PER_SEC / HZ; total += stats[i]; } info->tcpi_busy_time = total; info->tcpi_rwnd_limited = stats[TCP_CHRONO_RWND_LIMITED]; info->tcpi_sndbuf_limited = stats[TCP_CHRONO_SNDBUF_LIMITED]; } /* Return information about state of tcp endpoint in API format. */ void tcp_get_info(struct sock *sk, struct tcp_info *info) { const struct tcp_sock *tp = tcp_sk(sk); /* iff sk_type == SOCK_STREAM */ const struct inet_connection_sock *icsk = inet_csk(sk); unsigned long rate; u32 now; u64 rate64; bool slow; memset(info, 0, sizeof(*info)); if (sk->sk_type != SOCK_STREAM) return; info->tcpi_state = inet_sk_state_load(sk); /* Report meaningful fields for all TCP states, including listeners */ rate = READ_ONCE(sk->sk_pacing_rate); rate64 = (rate != ~0UL) ? rate : ~0ULL; info->tcpi_pacing_rate = rate64; rate = READ_ONCE(sk->sk_max_pacing_rate); rate64 = (rate != ~0UL) ? rate : ~0ULL; info->tcpi_max_pacing_rate = rate64; info->tcpi_reordering = tp->reordering; info->tcpi_snd_cwnd = tcp_snd_cwnd(tp); if (info->tcpi_state == TCP_LISTEN) { /* listeners aliased fields : * tcpi_unacked -> Number of children ready for accept() * tcpi_sacked -> max backlog */ info->tcpi_unacked = READ_ONCE(sk->sk_ack_backlog); info->tcpi_sacked = READ_ONCE(sk->sk_max_ack_backlog); return; } slow = lock_sock_fast(sk); info->tcpi_ca_state = icsk->icsk_ca_state; info->tcpi_retransmits = icsk->icsk_retransmits; info->tcpi_probes = icsk->icsk_probes_out; info->tcpi_backoff = icsk->icsk_backoff; if (tp->rx_opt.tstamp_ok) info->tcpi_options |= TCPI_OPT_TIMESTAMPS; if (tcp_is_sack(tp)) info->tcpi_options |= TCPI_OPT_SACK; if (tp->rx_opt.wscale_ok) { info->tcpi_options |= TCPI_OPT_WSCALE; info->tcpi_snd_wscale = tp->rx_opt.snd_wscale; info->tcpi_rcv_wscale = tp->rx_opt.rcv_wscale; } if (tp->ecn_flags & TCP_ECN_OK) info->tcpi_options |= TCPI_OPT_ECN; if (tp->ecn_flags & TCP_ECN_SEEN) info->tcpi_options |= TCPI_OPT_ECN_SEEN; if (tp->syn_data_acked) info->tcpi_options |= TCPI_OPT_SYN_DATA; info->tcpi_rto = jiffies_to_usecs(icsk->icsk_rto); info->tcpi_ato = jiffies_to_usecs(icsk->icsk_ack.ato); info->tcpi_snd_mss = tp->mss_cache; info->tcpi_rcv_mss = icsk->icsk_ack.rcv_mss; info->tcpi_unacked = tp->packets_out; info->tcpi_sacked = tp->sacked_out; info->tcpi_lost = tp->lost_out; info->tcpi_retrans = tp->retrans_out; now = tcp_jiffies32; info->tcpi_last_data_sent = jiffies_to_msecs(now - tp->lsndtime); info->tcpi_last_data_recv = jiffies_to_msecs(now - icsk->icsk_ack.lrcvtime); info->tcpi_last_ack_recv = jiffies_to_msecs(now - tp->rcv_tstamp); info->tcpi_pmtu = icsk->icsk_pmtu_cookie; info->tcpi_rcv_ssthresh = tp->rcv_ssthresh; info->tcpi_rtt = tp->srtt_us >> 3; info->tcpi_rttvar = tp->mdev_us >> 2; info->tcpi_snd_ssthresh = tp->snd_ssthresh; info->tcpi_advmss = tp->advmss; info->tcpi_rcv_rtt = tp->rcv_rtt_est.rtt_us >> 3; info->tcpi_rcv_space = tp->rcvq_space.space; info->tcpi_total_retrans = tp->total_retrans; info->tcpi_bytes_acked = tp->bytes_acked; info->tcpi_bytes_received = tp->bytes_received; info->tcpi_notsent_bytes = max_t(int, 0, tp->write_seq - tp->snd_nxt); tcp_get_info_chrono_stats(tp, info); info->tcpi_segs_out = tp->segs_out; /* segs_in and data_segs_in can be updated from tcp_segs_in() from BH */ info->tcpi_segs_in = READ_ONCE(tp->segs_in); info->tcpi_data_segs_in = READ_ONCE(tp->data_segs_in); info->tcpi_min_rtt = tcp_min_rtt(tp); info->tcpi_data_segs_out = tp->data_segs_out; info->tcpi_delivery_rate_app_limited = tp->rate_app_limited ? 1 : 0; rate64 = tcp_compute_delivery_rate(tp); if (rate64) info->tcpi_delivery_rate = rate64; info->tcpi_delivered = tp->delivered; info->tcpi_delivered_ce = tp->delivered_ce; info->tcpi_bytes_sent = tp->bytes_sent; info->tcpi_bytes_retrans = tp->bytes_retrans; info->tcpi_dsack_dups = tp->dsack_dups; info->tcpi_reord_seen = tp->reord_seen; info->tcpi_rcv_ooopack = tp->rcv_ooopack; info->tcpi_snd_wnd = tp->snd_wnd; info->tcpi_rcv_wnd = tp->rcv_wnd; info->tcpi_rehash = tp->plb_rehash + tp->timeout_rehash; info->tcpi_fastopen_client_fail = tp->fastopen_client_fail; unlock_sock_fast(sk, slow); } EXPORT_SYMBOL_GPL(tcp_get_info); static size_t tcp_opt_stats_get_size(void) { return nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_BUSY */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_RWND_LIMITED */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_SNDBUF_LIMITED */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_DATA_SEGS_OUT */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_TOTAL_RETRANS */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_PACING_RATE */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_DELIVERY_RATE */ nla_total_size(sizeof(u32)) + /* TCP_NLA_SND_CWND */ nla_total_size(sizeof(u32)) + /* TCP_NLA_REORDERING */ nla_total_size(sizeof(u32)) + /* TCP_NLA_MIN_RTT */ nla_total_size(sizeof(u8)) + /* TCP_NLA_RECUR_RETRANS */ nla_total_size(sizeof(u8)) + /* TCP_NLA_DELIVERY_RATE_APP_LMT */ nla_total_size(sizeof(u32)) + /* TCP_NLA_SNDQ_SIZE */ nla_total_size(sizeof(u8)) + /* TCP_NLA_CA_STATE */ nla_total_size(sizeof(u32)) + /* TCP_NLA_SND_SSTHRESH */ nla_total_size(sizeof(u32)) + /* TCP_NLA_DELIVERED */ nla_total_size(sizeof(u32)) + /* TCP_NLA_DELIVERED_CE */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_BYTES_SENT */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_BYTES_RETRANS */ nla_total_size(sizeof(u32)) + /* TCP_NLA_DSACK_DUPS */ nla_total_size(sizeof(u32)) + /* TCP_NLA_REORD_SEEN */ nla_total_size(sizeof(u32)) + /* TCP_NLA_SRTT */ nla_total_size(sizeof(u16)) + /* TCP_NLA_TIMEOUT_REHASH */ nla_total_size(sizeof(u32)) + /* TCP_NLA_BYTES_NOTSENT */ nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_EDT */ nla_total_size(sizeof(u8)) + /* TCP_NLA_TTL */ nla_total_size(sizeof(u32)) + /* TCP_NLA_REHASH */ 0; } /* Returns TTL or hop limit of an incoming packet from skb. */ static u8 tcp_skb_ttl_or_hop_limit(const struct sk_buff *skb) { if (skb->protocol == htons(ETH_P_IP)) return ip_hdr(skb)->ttl; else if (skb->protocol == htons(ETH_P_IPV6)) return ipv6_hdr(skb)->hop_limit; else return 0; } struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk, const struct sk_buff *orig_skb, const struct sk_buff *ack_skb) { const struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *stats; struct tcp_info info; unsigned long rate; u64 rate64; stats = alloc_skb(tcp_opt_stats_get_size(), GFP_ATOMIC); if (!stats) return NULL; tcp_get_info_chrono_stats(tp, &info); nla_put_u64_64bit(stats, TCP_NLA_BUSY, info.tcpi_busy_time, TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_RWND_LIMITED, info.tcpi_rwnd_limited, TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_SNDBUF_LIMITED, info.tcpi_sndbuf_limited, TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_DATA_SEGS_OUT, tp->data_segs_out, TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_TOTAL_RETRANS, tp->total_retrans, TCP_NLA_PAD); rate = READ_ONCE(sk->sk_pacing_rate); rate64 = (rate != ~0UL) ? rate : ~0ULL; nla_put_u64_64bit(stats, TCP_NLA_PACING_RATE, rate64, TCP_NLA_PAD); rate64 = tcp_compute_delivery_rate(tp); nla_put_u64_64bit(stats, TCP_NLA_DELIVERY_RATE, rate64, TCP_NLA_PAD); nla_put_u32(stats, TCP_NLA_SND_CWND, tcp_snd_cwnd(tp)); nla_put_u32(stats, TCP_NLA_REORDERING, tp->reordering); nla_put_u32(stats, TCP_NLA_MIN_RTT, tcp_min_rtt(tp)); nla_put_u8(stats, TCP_NLA_RECUR_RETRANS, inet_csk(sk)->icsk_retransmits); nla_put_u8(stats, TCP_NLA_DELIVERY_RATE_APP_LMT, !!tp->rate_app_limited); nla_put_u32(stats, TCP_NLA_SND_SSTHRESH, tp->snd_ssthresh); nla_put_u32(stats, TCP_NLA_DELIVERED, tp->delivered); nla_put_u32(stats, TCP_NLA_DELIVERED_CE, tp->delivered_ce); nla_put_u32(stats, TCP_NLA_SNDQ_SIZE, tp->write_seq - tp->snd_una); nla_put_u8(stats, TCP_NLA_CA_STATE, inet_csk(sk)->icsk_ca_state); nla_put_u64_64bit(stats, TCP_NLA_BYTES_SENT, tp->bytes_sent, TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_BYTES_RETRANS, tp->bytes_retrans, TCP_NLA_PAD); nla_put_u32(stats, TCP_NLA_DSACK_DUPS, tp->dsack_dups); nla_put_u32(stats, TCP_NLA_REORD_SEEN, tp->reord_seen); nla_put_u32(stats, TCP_NLA_SRTT, tp->srtt_us >> 3); nla_put_u16(stats, TCP_NLA_TIMEOUT_REHASH, tp->timeout_rehash); nla_put_u32(stats, TCP_NLA_BYTES_NOTSENT, max_t(int, 0, tp->write_seq - tp->snd_nxt)); nla_put_u64_64bit(stats, TCP_NLA_EDT, orig_skb->skb_mstamp_ns, TCP_NLA_PAD); if (ack_skb) nla_put_u8(stats, TCP_NLA_TTL, tcp_skb_ttl_or_hop_limit(ack_skb)); nla_put_u32(stats, TCP_NLA_REHASH, tp->plb_rehash + tp->timeout_rehash); return stats; } int do_tcp_getsockopt(struct sock *sk, int level, int optname, sockptr_t optval, sockptr_t optlen) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); int val, len; if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; len = min_t(unsigned int, len, sizeof(int)); if (len < 0) return -EINVAL; switch (optname) { case TCP_MAXSEG: val = tp->mss_cache; if (tp->rx_opt.user_mss && ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) val = tp->rx_opt.user_mss; if (tp->repair) val = tp->rx_opt.mss_clamp; break; case TCP_NODELAY: val = !!(tp->nonagle&TCP_NAGLE_OFF); break; case TCP_CORK: val = !!(tp->nonagle&TCP_NAGLE_CORK); break; case TCP_KEEPIDLE: val = keepalive_time_when(tp) / HZ; break; case TCP_KEEPINTVL: val = keepalive_intvl_when(tp) / HZ; break; case TCP_KEEPCNT: val = keepalive_probes(tp); break; case TCP_SYNCNT: val = READ_ONCE(icsk->icsk_syn_retries) ? : READ_ONCE(net->ipv4.sysctl_tcp_syn_retries); break; case TCP_LINGER2: val = READ_ONCE(tp->linger2); if (val >= 0) val = (val ? : READ_ONCE(net->ipv4.sysctl_tcp_fin_timeout)) / HZ; break; case TCP_DEFER_ACCEPT: val = READ_ONCE(icsk->icsk_accept_queue.rskq_defer_accept); val = retrans_to_secs(val, TCP_TIMEOUT_INIT / HZ, TCP_RTO_MAX / HZ); break; case TCP_WINDOW_CLAMP: val = tp->window_clamp; break; case TCP_INFO: { struct tcp_info info; if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; tcp_get_info(sk, &info); len = min_t(unsigned int, len, sizeof(info)); if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, &info, len)) return -EFAULT; return 0; } case TCP_CC_INFO: { const struct tcp_congestion_ops *ca_ops; union tcp_cc_info info; size_t sz = 0; int attr; if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; ca_ops = icsk->icsk_ca_ops; if (ca_ops && ca_ops->get_info) sz = ca_ops->get_info(sk, ~0U, &attr, &info); len = min_t(unsigned int, len, sz); if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, &info, len)) return -EFAULT; return 0; } case TCP_QUICKACK: val = !inet_csk_in_pingpong_mode(sk); break; case TCP_CONGESTION: if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; len = min_t(unsigned int, len, TCP_CA_NAME_MAX); if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, icsk->icsk_ca_ops->name, len)) return -EFAULT; return 0; case TCP_ULP: if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; len = min_t(unsigned int, len, TCP_ULP_NAME_MAX); if (!icsk->icsk_ulp_ops) { len = 0; if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; return 0; } if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, icsk->icsk_ulp_ops->name, len)) return -EFAULT; return 0; case TCP_FASTOPEN_KEY: { u64 key[TCP_FASTOPEN_KEY_BUF_LENGTH / sizeof(u64)]; unsigned int key_len; if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; key_len = tcp_fastopen_get_cipher(net, icsk, key) * TCP_FASTOPEN_KEY_LENGTH; len = min_t(unsigned int, len, key_len); if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, key, len)) return -EFAULT; return 0; } case TCP_THIN_LINEAR_TIMEOUTS: val = tp->thin_lto; break; case TCP_THIN_DUPACK: val = 0; break; case TCP_REPAIR: val = tp->repair; break; case TCP_REPAIR_QUEUE: if (tp->repair) val = tp->repair_queue; else return -EINVAL; break; case TCP_REPAIR_WINDOW: { struct tcp_repair_window opt; if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; if (len != sizeof(opt)) return -EINVAL; if (!tp->repair) return -EPERM; opt.snd_wl1 = tp->snd_wl1; opt.snd_wnd = tp->snd_wnd; opt.max_window = tp->max_window; opt.rcv_wnd = tp->rcv_wnd; opt.rcv_wup = tp->rcv_wup; if (copy_to_sockptr(optval, &opt, len)) return -EFAULT; return 0; } case TCP_QUEUE_SEQ: if (tp->repair_queue == TCP_SEND_QUEUE) val = tp->write_seq; else if (tp->repair_queue == TCP_RECV_QUEUE) val = tp->rcv_nxt; else return -EINVAL; break; case TCP_USER_TIMEOUT: val = READ_ONCE(icsk->icsk_user_timeout); break; case TCP_FASTOPEN: val = READ_ONCE(icsk->icsk_accept_queue.fastopenq.max_qlen); break; case TCP_FASTOPEN_CONNECT: val = tp->fastopen_connect; break; case TCP_FASTOPEN_NO_COOKIE: val = tp->fastopen_no_cookie; break; case TCP_TX_DELAY: val = READ_ONCE(tp->tcp_tx_delay); break; case TCP_TIMESTAMP: val = tcp_time_stamp_raw() + READ_ONCE(tp->tsoffset); break; case TCP_NOTSENT_LOWAT: val = READ_ONCE(tp->notsent_lowat); break; case TCP_INQ: val = tp->recvmsg_inq; break; case TCP_SAVE_SYN: val = tp->save_syn; break; case TCP_SAVED_SYN: { if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; sockopt_lock_sock(sk); if (tp->saved_syn) { if (len < tcp_saved_syn_len(tp->saved_syn)) { len = tcp_saved_syn_len(tp->saved_syn); if (copy_to_sockptr(optlen, &len, sizeof(int))) { sockopt_release_sock(sk); return -EFAULT; } sockopt_release_sock(sk); return -EINVAL; } len = tcp_saved_syn_len(tp->saved_syn); if (copy_to_sockptr(optlen, &len, sizeof(int))) { sockopt_release_sock(sk); return -EFAULT; } if (copy_to_sockptr(optval, tp->saved_syn->data, len)) { sockopt_release_sock(sk); return -EFAULT; } tcp_saved_syn_free(tp); sockopt_release_sock(sk); } else { sockopt_release_sock(sk); len = 0; if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; } return 0; } #ifdef CONFIG_MMU case TCP_ZEROCOPY_RECEIVE: { struct scm_timestamping_internal tss; struct tcp_zerocopy_receive zc = {}; int err; if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; if (len < 0 || len < offsetofend(struct tcp_zerocopy_receive, length)) return -EINVAL; if (unlikely(len > sizeof(zc))) { err = check_zeroed_sockptr(optval, sizeof(zc), len - sizeof(zc)); if (err < 1) return err == 0 ? -EINVAL : err; len = sizeof(zc); if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; } if (copy_from_sockptr(&zc, optval, len)) return -EFAULT; if (zc.reserved) return -EINVAL; if (zc.msg_flags & ~(TCP_VALID_ZC_MSG_FLAGS)) return -EINVAL; sockopt_lock_sock(sk); err = tcp_zerocopy_receive(sk, &zc, &tss); err = BPF_CGROUP_RUN_PROG_GETSOCKOPT_KERN(sk, level, optname, &zc, &len, err); sockopt_release_sock(sk); if (len >= offsetofend(struct tcp_zerocopy_receive, msg_flags)) goto zerocopy_rcv_cmsg; switch (len) { case offsetofend(struct tcp_zerocopy_receive, msg_flags): goto zerocopy_rcv_cmsg; case offsetofend(struct tcp_zerocopy_receive, msg_controllen): case offsetofend(struct tcp_zerocopy_receive, msg_control): case offsetofend(struct tcp_zerocopy_receive, flags): case offsetofend(struct tcp_zerocopy_receive, copybuf_len): case offsetofend(struct tcp_zerocopy_receive, copybuf_address): case offsetofend(struct tcp_zerocopy_receive, err): goto zerocopy_rcv_sk_err; case offsetofend(struct tcp_zerocopy_receive, inq): goto zerocopy_rcv_inq; case offsetofend(struct tcp_zerocopy_receive, length): default: goto zerocopy_rcv_out; } zerocopy_rcv_cmsg: if (zc.msg_flags & TCP_CMSG_TS) tcp_zc_finalize_rx_tstamp(sk, &zc, &tss); else zc.msg_flags = 0; zerocopy_rcv_sk_err: if (!err) zc.err = sock_error(sk); zerocopy_rcv_inq: zc.inq = tcp_inq_hint(sk); zerocopy_rcv_out: if (!err && copy_to_sockptr(optval, &zc, len)) err = -EFAULT; return err; } #endif default: return -ENOPROTOOPT; } if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, &val, len)) return -EFAULT; return 0; } bool tcp_bpf_bypass_getsockopt(int level, int optname) { /* TCP do_tcp_getsockopt has optimized getsockopt implementation * to avoid extra socket lock for TCP_ZEROCOPY_RECEIVE. */ if (level == SOL_TCP && optname == TCP_ZEROCOPY_RECEIVE) return true; return false; } EXPORT_SYMBOL(tcp_bpf_bypass_getsockopt); int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { struct inet_connection_sock *icsk = inet_csk(sk); if (level != SOL_TCP) /* Paired with WRITE_ONCE() in do_ipv6_setsockopt() and tcp_v6_connect() */ return READ_ONCE(icsk->icsk_af_ops)->getsockopt(sk, level, optname, optval, optlen); return do_tcp_getsockopt(sk, level, optname, USER_SOCKPTR(optval), USER_SOCKPTR(optlen)); } EXPORT_SYMBOL(tcp_getsockopt); #ifdef CONFIG_TCP_MD5SIG static DEFINE_PER_CPU(struct tcp_md5sig_pool, tcp_md5sig_pool); static DEFINE_MUTEX(tcp_md5sig_mutex); static bool tcp_md5sig_pool_populated = false; static void __tcp_alloc_md5sig_pool(void) { struct crypto_ahash *hash; int cpu; hash = crypto_alloc_ahash("md5", 0, CRYPTO_ALG_ASYNC); if (IS_ERR(hash)) return; for_each_possible_cpu(cpu) { void *scratch = per_cpu(tcp_md5sig_pool, cpu).scratch; struct ahash_request *req; if (!scratch) { scratch = kmalloc_node(sizeof(union tcp_md5sum_block) + sizeof(struct tcphdr), GFP_KERNEL, cpu_to_node(cpu)); if (!scratch) return; per_cpu(tcp_md5sig_pool, cpu).scratch = scratch; } if (per_cpu(tcp_md5sig_pool, cpu).md5_req) continue; req = ahash_request_alloc(hash, GFP_KERNEL); if (!req) return; ahash_request_set_callback(req, 0, NULL, NULL); per_cpu(tcp_md5sig_pool, cpu).md5_req = req; } /* before setting tcp_md5sig_pool_populated, we must commit all writes * to memory. See smp_rmb() in tcp_get_md5sig_pool() */ smp_wmb(); /* Paired with READ_ONCE() from tcp_alloc_md5sig_pool() * and tcp_get_md5sig_pool(). */ WRITE_ONCE(tcp_md5sig_pool_populated, true); } bool tcp_alloc_md5sig_pool(void) { /* Paired with WRITE_ONCE() from __tcp_alloc_md5sig_pool() */ if (unlikely(!READ_ONCE(tcp_md5sig_pool_populated))) { mutex_lock(&tcp_md5sig_mutex); if (!tcp_md5sig_pool_populated) __tcp_alloc_md5sig_pool(); mutex_unlock(&tcp_md5sig_mutex); } /* Paired with WRITE_ONCE() from __tcp_alloc_md5sig_pool() */ return READ_ONCE(tcp_md5sig_pool_populated); } EXPORT_SYMBOL(tcp_alloc_md5sig_pool); /** * tcp_get_md5sig_pool - get md5sig_pool for this user * * We use percpu structure, so if we succeed, we exit with preemption * and BH disabled, to make sure another thread or softirq handling * wont try to get same context. */ struct tcp_md5sig_pool *tcp_get_md5sig_pool(void) { local_bh_disable(); /* Paired with WRITE_ONCE() from __tcp_alloc_md5sig_pool() */ if (READ_ONCE(tcp_md5sig_pool_populated)) { /* coupled with smp_wmb() in __tcp_alloc_md5sig_pool() */ smp_rmb(); return this_cpu_ptr(&tcp_md5sig_pool); } local_bh_enable(); return NULL; } EXPORT_SYMBOL(tcp_get_md5sig_pool); int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp, const struct sk_buff *skb, unsigned int header_len) { struct scatterlist sg; const struct tcphdr *tp = tcp_hdr(skb); struct ahash_request *req = hp->md5_req; unsigned int i; const unsigned int head_data_len = skb_headlen(skb) > header_len ? skb_headlen(skb) - header_len : 0; const struct skb_shared_info *shi = skb_shinfo(skb); struct sk_buff *frag_iter; sg_init_table(&sg, 1); sg_set_buf(&sg, ((u8 *) tp) + header_len, head_data_len); ahash_request_set_crypt(req, &sg, NULL, head_data_len); if (crypto_ahash_update(req)) return 1; for (i = 0; i < shi->nr_frags; ++i) { const skb_frag_t *f = &shi->frags[i]; unsigned int offset = skb_frag_off(f); struct page *page = skb_frag_page(f) + (offset >> PAGE_SHIFT); sg_set_page(&sg, page, skb_frag_size(f), offset_in_page(offset)); ahash_request_set_crypt(req, &sg, NULL, skb_frag_size(f)); if (crypto_ahash_update(req)) return 1; } skb_walk_frags(skb, frag_iter) if (tcp_md5_hash_skb_data(hp, frag_iter, 0)) return 1; return 0; } EXPORT_SYMBOL(tcp_md5_hash_skb_data); int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, const struct tcp_md5sig_key *key) { u8 keylen = READ_ONCE(key->keylen); /* paired with WRITE_ONCE() in tcp_md5_do_add */ struct scatterlist sg; sg_init_one(&sg, key->key, keylen); ahash_request_set_crypt(hp->md5_req, &sg, NULL, keylen); /* We use data_race() because tcp_md5_do_add() might change key->key under us */ return data_race(crypto_ahash_update(hp->md5_req)); } EXPORT_SYMBOL(tcp_md5_hash_key); /* Called with rcu_read_lock() */ enum skb_drop_reason tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, const void *saddr, const void *daddr, int family, int dif, int sdif) { /* * This gets called for each TCP segment that arrives * so we want to be efficient. * We have 3 drop cases: * o No MD5 hash and one expected. * o MD5 hash and we're not expecting one. * o MD5 hash and its wrong. */ const __u8 *hash_location = NULL; struct tcp_md5sig_key *hash_expected; const struct tcphdr *th = tcp_hdr(skb); const struct tcp_sock *tp = tcp_sk(sk); int genhash, l3index; u8 newhash[16]; /* sdif set, means packet ingressed via a device * in an L3 domain and dif is set to the l3mdev */ l3index = sdif ? dif : 0; hash_expected = tcp_md5_do_lookup(sk, l3index, saddr, family); hash_location = tcp_parse_md5sig_option(th); /* We've parsed the options - do we have a hash? */ if (!hash_expected && !hash_location) return SKB_NOT_DROPPED_YET; if (hash_expected && !hash_location) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); return SKB_DROP_REASON_TCP_MD5NOTFOUND; } if (!hash_expected && hash_location) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); return SKB_DROP_REASON_TCP_MD5UNEXPECTED; } /* Check the signature. * To support dual stack listeners, we need to handle * IPv4-mapped case. */ if (family == AF_INET) genhash = tcp_v4_md5_hash_skb(newhash, hash_expected, NULL, skb); else genhash = tp->af_specific->calc_md5_hash(newhash, hash_expected, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); if (family == AF_INET) { net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s L3 index %d\n", saddr, ntohs(th->source), daddr, ntohs(th->dest), genhash ? " tcp_v4_calc_md5_hash failed" : "", l3index); } else { net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u L3 index %d\n", genhash ? "failed" : "mismatch", saddr, ntohs(th->source), daddr, ntohs(th->dest), l3index); } return SKB_DROP_REASON_TCP_MD5FAILURE; } return SKB_NOT_DROPPED_YET; } EXPORT_SYMBOL(tcp_inbound_md5_hash); #endif void tcp_done(struct sock *sk) { struct request_sock *req; /* We might be called with a new socket, after * inet_csk_prepare_forced_close() has been called * so we can not use lockdep_sock_is_held(sk) */ req = rcu_dereference_protected(tcp_sk(sk)->fastopen_rsk, 1); if (sk->sk_state == TCP_SYN_SENT || sk->sk_state == TCP_SYN_RECV) TCP_INC_STATS(sock_net(sk), TCP_MIB_ATTEMPTFAILS); tcp_set_state(sk, TCP_CLOSE); tcp_clear_xmit_timers(sk); if (req) reqsk_fastopen_remove(sk, req, false); WRITE_ONCE(sk->sk_shutdown, SHUTDOWN_MASK); if (!sock_flag(sk, SOCK_DEAD)) sk->sk_state_change(sk); else inet_csk_destroy_sock(sk); } EXPORT_SYMBOL_GPL(tcp_done); int tcp_abort(struct sock *sk, int err) { int state = inet_sk_state_load(sk); if (state == TCP_NEW_SYN_RECV) { struct request_sock *req = inet_reqsk(sk); local_bh_disable(); inet_csk_reqsk_queue_drop(req->rsk_listener, req); local_bh_enable(); return 0; } if (state == TCP_TIME_WAIT) { struct inet_timewait_sock *tw = inet_twsk(sk); refcount_inc(&tw->tw_refcnt); local_bh_disable(); inet_twsk_deschedule_put(tw); local_bh_enable(); return 0; } /* BPF context ensures sock locking. */ if (!has_current_bpf_ctx()) /* Don't race with userspace socket closes such as tcp_close. */ lock_sock(sk); if (sk->sk_state == TCP_LISTEN) { tcp_set_state(sk, TCP_CLOSE); inet_csk_listen_stop(sk); } /* Don't race with BH socket closes such as inet_csk_listen_stop. */ local_bh_disable(); bh_lock_sock(sk); if (!sock_flag(sk, SOCK_DEAD)) { WRITE_ONCE(sk->sk_err, err); /* This barrier is coupled with smp_rmb() in tcp_poll() */ smp_wmb(); sk_error_report(sk); if (tcp_need_reset(sk->sk_state)) tcp_send_active_reset(sk, GFP_ATOMIC); tcp_done(sk); } bh_unlock_sock(sk); local_bh_enable(); tcp_write_queue_purge(sk); if (!has_current_bpf_ctx()) release_sock(sk); return 0; } EXPORT_SYMBOL_GPL(tcp_abort); extern struct tcp_congestion_ops tcp_reno; static __initdata unsigned long thash_entries; static int __init set_thash_entries(char *str) { ssize_t ret; if (!str) return 0; ret = kstrtoul(str, 0, &thash_entries); if (ret) return 0; return 1; } __setup("thash_entries=", set_thash_entries); static void __init tcp_init_mem(void) { unsigned long limit = nr_free_buffer_pages() / 16; limit = max(limit, 128UL); sysctl_tcp_mem[0] = limit / 4 * 3; /* 4.68 % */ sysctl_tcp_mem[1] = limit; /* 6.25 % */ sysctl_tcp_mem[2] = sysctl_tcp_mem[0] * 2; /* 9.37 % */ } void __init tcp_init(void) { int max_rshare, max_wshare, cnt; unsigned long limit; unsigned int i; BUILD_BUG_ON(TCP_MIN_SND_MSS <= MAX_TCP_OPTION_SPACE); BUILD_BUG_ON(sizeof(struct tcp_skb_cb) > sizeof_field(struct sk_buff, cb)); percpu_counter_init(&tcp_sockets_allocated, 0, GFP_KERNEL); timer_setup(&tcp_orphan_timer, tcp_orphan_update, TIMER_DEFERRABLE); mod_timer(&tcp_orphan_timer, jiffies + TCP_ORPHAN_TIMER_PERIOD); inet_hashinfo2_init(&tcp_hashinfo, "tcp_listen_portaddr_hash", thash_entries, 21, /* one slot per 2 MB*/ 0, 64 * 1024); tcp_hashinfo.bind_bucket_cachep = kmem_cache_create("tcp_bind_bucket", sizeof(struct inet_bind_bucket), 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT, NULL); tcp_hashinfo.bind2_bucket_cachep = kmem_cache_create("tcp_bind2_bucket", sizeof(struct inet_bind2_bucket), 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT, NULL); /* Size and allocate the main established and bind bucket * hash tables. * * The methodology is similar to that of the buffer cache. */ tcp_hashinfo.ehash = alloc_large_system_hash("TCP established", sizeof(struct inet_ehash_bucket), thash_entries, 17, /* one slot per 128 KB of memory */ 0, NULL, &tcp_hashinfo.ehash_mask, 0, thash_entries ? 0 : 512 * 1024); for (i = 0; i <= tcp_hashinfo.ehash_mask; i++) INIT_HLIST_NULLS_HEAD(&tcp_hashinfo.ehash[i].chain, i); if (inet_ehash_locks_alloc(&tcp_hashinfo)) panic("TCP: failed to alloc ehash_locks"); tcp_hashinfo.bhash = alloc_large_system_hash("TCP bind", 2 * sizeof(struct inet_bind_hashbucket), tcp_hashinfo.ehash_mask + 1, 17, /* one slot per 128 KB of memory */ 0, &tcp_hashinfo.bhash_size, NULL, 0, 64 * 1024); tcp_hashinfo.bhash_size = 1U << tcp_hashinfo.bhash_size; tcp_hashinfo.bhash2 = tcp_hashinfo.bhash + tcp_hashinfo.bhash_size; for (i = 0; i < tcp_hashinfo.bhash_size; i++) { spin_lock_init(&tcp_hashinfo.bhash[i].lock); INIT_HLIST_HEAD(&tcp_hashinfo.bhash[i].chain); spin_lock_init(&tcp_hashinfo.bhash2[i].lock); INIT_HLIST_HEAD(&tcp_hashinfo.bhash2[i].chain); } tcp_hashinfo.pernet = false; cnt = tcp_hashinfo.ehash_mask + 1; sysctl_tcp_max_orphans = cnt / 2; tcp_init_mem(); /* Set per-socket limits to no more than 1/128 the pressure threshold */ limit = nr_free_buffer_pages() << (PAGE_SHIFT - 7); max_wshare = min(4UL*1024*1024, limit); max_rshare = min(6UL*1024*1024, limit); init_net.ipv4.sysctl_tcp_wmem[0] = PAGE_SIZE; init_net.ipv4.sysctl_tcp_wmem[1] = 16*1024; init_net.ipv4.sysctl_tcp_wmem[2] = max(64*1024, max_wshare); init_net.ipv4.sysctl_tcp_rmem[0] = PAGE_SIZE; init_net.ipv4.sysctl_tcp_rmem[1] = 131072; init_net.ipv4.sysctl_tcp_rmem[2] = max(131072, max_rshare); pr_info("Hash tables configured (established %u bind %u)\n", tcp_hashinfo.ehash_mask + 1, tcp_hashinfo.bhash_size); tcp_v4_init(); tcp_metrics_init(); BUG_ON(tcp_register_congestion_control(&tcp_reno) != 0); tcp_tasklet_init(); mptcp_init(); }
linux-master
net/ipv4/tcp.c
// SPDX-License-Identifier: GPL-2.0-only /* xfrm4_tunnel.c: Generic IP tunnel transformer. * * Copyright (C) 2003 David S. Miller ([email protected]) */ #define pr_fmt(fmt) "IPsec: " fmt #include <linux/skbuff.h> #include <linux/module.h> #include <net/xfrm.h> #include <net/protocol.h> static int ipip_output(struct xfrm_state *x, struct sk_buff *skb) { skb_push(skb, -skb_network_offset(skb)); return 0; } static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb) { return ip_hdr(skb)->protocol; } static int ipip_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack) { if (x->props.mode != XFRM_MODE_TUNNEL) { NL_SET_ERR_MSG(extack, "IPv4 tunnel can only be used with tunnel mode"); return -EINVAL; } if (x->encap) { NL_SET_ERR_MSG(extack, "IPv4 tunnel is not compatible with encapsulation"); return -EINVAL; } x->props.header_len = sizeof(struct iphdr); return 0; } static void ipip_destroy(struct xfrm_state *x) { } static const struct xfrm_type ipip_type = { .owner = THIS_MODULE, .proto = IPPROTO_IPIP, .init_state = ipip_init_state, .destructor = ipip_destroy, .input = ipip_xfrm_rcv, .output = ipip_output }; static int xfrm_tunnel_rcv(struct sk_buff *skb) { return xfrm4_rcv_spi(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr); } static int xfrm_tunnel_err(struct sk_buff *skb, u32 info) { return -ENOENT; } static struct xfrm_tunnel xfrm_tunnel_handler __read_mostly = { .handler = xfrm_tunnel_rcv, .err_handler = xfrm_tunnel_err, .priority = 4, }; #if IS_ENABLED(CONFIG_IPV6) static struct xfrm_tunnel xfrm64_tunnel_handler __read_mostly = { .handler = xfrm_tunnel_rcv, .err_handler = xfrm_tunnel_err, .priority = 3, }; #endif static int __init ipip_init(void) { if (xfrm_register_type(&ipip_type, AF_INET) < 0) { pr_info("%s: can't add xfrm type\n", __func__); return -EAGAIN; } if (xfrm4_tunnel_register(&xfrm_tunnel_handler, AF_INET)) { pr_info("%s: can't add xfrm handler for AF_INET\n", __func__); xfrm_unregister_type(&ipip_type, AF_INET); return -EAGAIN; } #if IS_ENABLED(CONFIG_IPV6) if (xfrm4_tunnel_register(&xfrm64_tunnel_handler, AF_INET6)) { pr_info("%s: can't add xfrm handler for AF_INET6\n", __func__); xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET); xfrm_unregister_type(&ipip_type, AF_INET); return -EAGAIN; } #endif return 0; } static void __exit ipip_fini(void) { #if IS_ENABLED(CONFIG_IPV6) if (xfrm4_tunnel_deregister(&xfrm64_tunnel_handler, AF_INET6)) pr_info("%s: can't remove xfrm handler for AF_INET6\n", __func__); #endif if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET)) pr_info("%s: can't remove xfrm handler for AF_INET\n", __func__); xfrm_unregister_type(&ipip_type, AF_INET); } module_init(ipip_init); module_exit(ipip_fini); MODULE_LICENSE("GPL"); MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_IPIP);
linux-master
net/ipv4/xfrm4_tunnel.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * Linux NET3: IP/IP protocol decoder. * * Authors: * Sam Lantinga ([email protected]) 02/01/95 * * Fixes: * Alan Cox : Merged and made usable non modular (its so tiny its silly as * a module taking up 2 pages). * Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph) * to keep ip_forward happy. * Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8). * Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL * David Woodhouse : Perform some basic ICMP handling. * IPIP Routing without decapsulation. * Carlos Picoto : GRE over IP support * Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c. * I do not want to merge them together. */ /* tunnel.c: an IP tunnel driver The purpose of this driver is to provide an IP tunnel through which you can tunnel network traffic transparently across subnets. This was written by looking at Nick Holloway's dummy driver Thanks for the great code! -Sam Lantinga ([email protected]) 02/01/95 Minor tweaks: Cleaned up the code a little and added some pre-1.3.0 tweaks. dev->hard_header/hard_header_len changed to use no headers. Comments/bracketing tweaked. Made the tunnels use dev->name not tunnel: when error reporting. Added tx_dropped stat -Alan Cox ([email protected]) 21 March 95 Reworked: Changed to tunnel to destination gateway in addition to the tunnel's pointopoint address Almost completely rewritten Note: There is currently no firewall or ICMP handling done. -Sam Lantinga ([email protected]) 02/13/96 */ /* Things I wish I had known when writing the tunnel driver: When the tunnel_xmit() function is called, the skb contains the packet to be sent (plus a great deal of extra info), and dev contains the tunnel device that _we_ are. When we are passed a packet, we are expected to fill in the source address with our source IP address. What is the proper way to allocate, copy and free a buffer? After you allocate it, it is a "0 length" chunk of memory starting at zero. If you want to add headers to the buffer later, you'll have to call "skb_reserve(skb, amount)" with the amount of memory you want reserved. Then, you call "skb_put(skb, amount)" with the amount of space you want in the buffer. skb_put() returns a pointer to the top (#0) of that buffer. skb->len is set to the amount of space you have "allocated" with skb_put(). You can then write up to skb->len bytes to that buffer. If you need more, you can call skb_put() again with the additional amount of space you need. You can find out how much more space you can allocate by calling "skb_tailroom(skb)". Now, to add header space, call "skb_push(skb, header_len)". This creates space at the beginning of the buffer and returns a pointer to this new space. If later you need to strip a header from a buffer, call "skb_pull(skb, header_len)". skb_headroom() will return how much space is left at the top of the buffer (before the main data). Remember, this headroom space must be reserved before the skb_put() function is called. */ /* This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c For comments look at net/ipv4/ip_gre.c --ANK */ #include <linux/capability.h> #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/uaccess.h> #include <linux/skbuff.h> #include <linux/netdevice.h> #include <linux/in.h> #include <linux/tcp.h> #include <linux/udp.h> #include <linux/if_arp.h> #include <linux/init.h> #include <linux/netfilter_ipv4.h> #include <linux/if_ether.h> #include <net/sock.h> #include <net/ip.h> #include <net/icmp.h> #include <net/ip_tunnels.h> #include <net/inet_ecn.h> #include <net/xfrm.h> #include <net/net_namespace.h> #include <net/netns/generic.h> #include <net/dst_metadata.h> static bool log_ecn_error = true; module_param(log_ecn_error, bool, 0644); MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); static unsigned int ipip_net_id __read_mostly; static int ipip_tunnel_init(struct net_device *dev); static struct rtnl_link_ops ipip_link_ops __read_mostly; static int ipip_err(struct sk_buff *skb, u32 info) { /* All the routers (except for Linux) return only * 8 bytes of packet payload. It means, that precise relaying of * ICMP in the real Internet is absolutely infeasible. */ struct net *net = dev_net(skb->dev); struct ip_tunnel_net *itn = net_generic(net, ipip_net_id); const struct iphdr *iph = (const struct iphdr *)skb->data; const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; struct ip_tunnel *t; int err = 0; t = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY, iph->daddr, iph->saddr, 0); if (!t) { err = -ENOENT; goto out; } switch (type) { case ICMP_DEST_UNREACH: switch (code) { case ICMP_SR_FAILED: /* Impossible event. */ goto out; default: /* All others are translated to HOST_UNREACH. * rfc2003 contains "deep thoughts" about NET_UNREACH, * I believe they are just ether pollution. --ANK */ break; } break; case ICMP_TIME_EXCEEDED: if (code != ICMP_EXC_TTL) goto out; break; case ICMP_REDIRECT: break; default: goto out; } if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { ipv4_update_pmtu(skb, net, info, t->parms.link, iph->protocol); goto out; } if (type == ICMP_REDIRECT) { ipv4_redirect(skb, net, t->parms.link, iph->protocol); goto out; } if (t->parms.iph.daddr == 0) { err = -ENOENT; goto out; } if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) goto out; if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) t->err_count++; else t->err_count = 1; t->err_time = jiffies; out: return err; } static const struct tnl_ptk_info ipip_tpi = { /* no tunnel info required for ipip. */ .proto = htons(ETH_P_IP), }; #if IS_ENABLED(CONFIG_MPLS) static const struct tnl_ptk_info mplsip_tpi = { /* no tunnel info required for mplsip. */ .proto = htons(ETH_P_MPLS_UC), }; #endif static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto) { struct net *net = dev_net(skb->dev); struct ip_tunnel_net *itn = net_generic(net, ipip_net_id); struct metadata_dst *tun_dst = NULL; struct ip_tunnel *tunnel; const struct iphdr *iph; iph = ip_hdr(skb); tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY, iph->saddr, iph->daddr, 0); if (tunnel) { const struct tnl_ptk_info *tpi; if (tunnel->parms.iph.protocol != ipproto && tunnel->parms.iph.protocol != 0) goto drop; if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) goto drop; #if IS_ENABLED(CONFIG_MPLS) if (ipproto == IPPROTO_MPLS) tpi = &mplsip_tpi; else #endif tpi = &ipip_tpi; if (iptunnel_pull_header(skb, 0, tpi->proto, false)) goto drop; if (tunnel->collect_md) { tun_dst = ip_tun_rx_dst(skb, 0, 0, 0); if (!tun_dst) return 0; ip_tunnel_md_udp_encap(skb, &tun_dst->u.tun_info); } skb_reset_mac_header(skb); return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); } return -1; drop: kfree_skb(skb); return 0; } static int ipip_rcv(struct sk_buff *skb) { return ipip_tunnel_rcv(skb, IPPROTO_IPIP); } #if IS_ENABLED(CONFIG_MPLS) static int mplsip_rcv(struct sk_buff *skb) { return ipip_tunnel_rcv(skb, IPPROTO_MPLS); } #endif /* * This function assumes it is being called from dev_queue_xmit() * and that skb is filled properly by that function. */ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); const struct iphdr *tiph = &tunnel->parms.iph; u8 ipproto; if (!pskb_inet_may_pull(skb)) goto tx_error; switch (skb->protocol) { case htons(ETH_P_IP): ipproto = IPPROTO_IPIP; break; #if IS_ENABLED(CONFIG_MPLS) case htons(ETH_P_MPLS_UC): ipproto = IPPROTO_MPLS; break; #endif default: goto tx_error; } if (tiph->protocol != ipproto && tiph->protocol != 0) goto tx_error; if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4)) goto tx_error; skb_set_inner_ipproto(skb, ipproto); if (tunnel->collect_md) ip_md_tunnel_xmit(skb, dev, ipproto, 0); else ip_tunnel_xmit(skb, dev, tiph, ipproto); return NETDEV_TX_OK; tx_error: kfree_skb(skb); DEV_STATS_INC(dev, tx_errors); return NETDEV_TX_OK; } static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto) { switch (ipproto) { case 0: case IPPROTO_IPIP: #if IS_ENABLED(CONFIG_MPLS) case IPPROTO_MPLS: #endif return true; } return false; } static int ipip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) { if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { if (p->iph.version != 4 || !ipip_tunnel_ioctl_verify_protocol(p->iph.protocol) || p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF))) return -EINVAL; } p->i_key = p->o_key = 0; p->i_flags = p->o_flags = 0; return ip_tunnel_ctl(dev, p, cmd); } static const struct net_device_ops ipip_netdev_ops = { .ndo_init = ipip_tunnel_init, .ndo_uninit = ip_tunnel_uninit, .ndo_start_xmit = ipip_tunnel_xmit, .ndo_siocdevprivate = ip_tunnel_siocdevprivate, .ndo_change_mtu = ip_tunnel_change_mtu, .ndo_get_stats64 = dev_get_tstats64, .ndo_get_iflink = ip_tunnel_get_iflink, .ndo_tunnel_ctl = ipip_tunnel_ctl, }; #define IPIP_FEATURES (NETIF_F_SG | \ NETIF_F_FRAGLIST | \ NETIF_F_HIGHDMA | \ NETIF_F_GSO_SOFTWARE | \ NETIF_F_HW_CSUM) static void ipip_tunnel_setup(struct net_device *dev) { dev->netdev_ops = &ipip_netdev_ops; dev->header_ops = &ip_tunnel_header_ops; dev->type = ARPHRD_TUNNEL; dev->flags = IFF_NOARP; dev->addr_len = 4; dev->features |= NETIF_F_LLTX; netif_keep_dst(dev); dev->features |= IPIP_FEATURES; dev->hw_features |= IPIP_FEATURES; ip_tunnel_setup(dev, ipip_net_id); } static int ipip_tunnel_init(struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); __dev_addr_set(dev, &tunnel->parms.iph.saddr, 4); memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); tunnel->tun_hlen = 0; tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; return ip_tunnel_init(dev); } static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { u8 proto; if (!data || !data[IFLA_IPTUN_PROTO]) return 0; proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); if (proto != IPPROTO_IPIP && proto != IPPROTO_MPLS && proto != 0) return -EINVAL; return 0; } static void ipip_netlink_parms(struct nlattr *data[], struct ip_tunnel_parm *parms, bool *collect_md, __u32 *fwmark) { memset(parms, 0, sizeof(*parms)); parms->iph.version = 4; parms->iph.protocol = IPPROTO_IPIP; parms->iph.ihl = 5; *collect_md = false; if (!data) return; ip_tunnel_netlink_parms(data, parms); if (data[IFLA_IPTUN_COLLECT_METADATA]) *collect_md = true; if (data[IFLA_IPTUN_FWMARK]) *fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); } static int ipip_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { struct ip_tunnel *t = netdev_priv(dev); struct ip_tunnel_parm p; struct ip_tunnel_encap ipencap; __u32 fwmark = 0; if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { int err = ip_tunnel_encap_setup(t, &ipencap); if (err < 0) return err; } ipip_netlink_parms(data, &p, &t->collect_md, &fwmark); return ip_tunnel_newlink(dev, tb, &p, fwmark); } static int ipip_changelink(struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { struct ip_tunnel *t = netdev_priv(dev); struct ip_tunnel_parm p; struct ip_tunnel_encap ipencap; bool collect_md; __u32 fwmark = t->fwmark; if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { int err = ip_tunnel_encap_setup(t, &ipencap); if (err < 0) return err; } ipip_netlink_parms(data, &p, &collect_md, &fwmark); if (collect_md) return -EINVAL; if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) || (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr)) return -EINVAL; return ip_tunnel_changelink(dev, tb, &p, fwmark); } static size_t ipip_get_size(const struct net_device *dev) { return /* IFLA_IPTUN_LINK */ nla_total_size(4) + /* IFLA_IPTUN_LOCAL */ nla_total_size(4) + /* IFLA_IPTUN_REMOTE */ nla_total_size(4) + /* IFLA_IPTUN_TTL */ nla_total_size(1) + /* IFLA_IPTUN_TOS */ nla_total_size(1) + /* IFLA_IPTUN_PROTO */ nla_total_size(1) + /* IFLA_IPTUN_PMTUDISC */ nla_total_size(1) + /* IFLA_IPTUN_ENCAP_TYPE */ nla_total_size(2) + /* IFLA_IPTUN_ENCAP_FLAGS */ nla_total_size(2) + /* IFLA_IPTUN_ENCAP_SPORT */ nla_total_size(2) + /* IFLA_IPTUN_ENCAP_DPORT */ nla_total_size(2) + /* IFLA_IPTUN_COLLECT_METADATA */ nla_total_size(0) + /* IFLA_IPTUN_FWMARK */ nla_total_size(4) + 0; } static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); struct ip_tunnel_parm *parm = &tunnel->parms; if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) || nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) || nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) || nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) || nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) || nla_put_u8(skb, IFLA_IPTUN_PMTUDISC, !!(parm->iph.frag_off & htons(IP_DF))) || nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark)) goto nla_put_failure; if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) goto nla_put_failure; if (tunnel->collect_md) if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) goto nla_put_failure; return 0; nla_put_failure: return -EMSGSIZE; } static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = { [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 }, [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 }, [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, [IFLA_IPTUN_TOS] = { .type = NLA_U8 }, [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 }, [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, }; static struct rtnl_link_ops ipip_link_ops __read_mostly = { .kind = "ipip", .maxtype = IFLA_IPTUN_MAX, .policy = ipip_policy, .priv_size = sizeof(struct ip_tunnel), .setup = ipip_tunnel_setup, .validate = ipip_tunnel_validate, .newlink = ipip_newlink, .changelink = ipip_changelink, .dellink = ip_tunnel_dellink, .get_size = ipip_get_size, .fill_info = ipip_fill_info, .get_link_net = ip_tunnel_get_link_net, }; static struct xfrm_tunnel ipip_handler __read_mostly = { .handler = ipip_rcv, .err_handler = ipip_err, .priority = 1, }; #if IS_ENABLED(CONFIG_MPLS) static struct xfrm_tunnel mplsip_handler __read_mostly = { .handler = mplsip_rcv, .err_handler = ipip_err, .priority = 1, }; #endif static int __net_init ipip_init_net(struct net *net) { return ip_tunnel_init_net(net, ipip_net_id, &ipip_link_ops, "tunl0"); } static void __net_exit ipip_exit_batch_net(struct list_head *list_net) { ip_tunnel_delete_nets(list_net, ipip_net_id, &ipip_link_ops); } static struct pernet_operations ipip_net_ops = { .init = ipip_init_net, .exit_batch = ipip_exit_batch_net, .id = &ipip_net_id, .size = sizeof(struct ip_tunnel_net), }; static int __init ipip_init(void) { int err; pr_info("ipip: IPv4 and MPLS over IPv4 tunneling driver\n"); err = register_pernet_device(&ipip_net_ops); if (err < 0) return err; err = xfrm4_tunnel_register(&ipip_handler, AF_INET); if (err < 0) { pr_info("%s: can't register tunnel\n", __func__); goto xfrm_tunnel_ipip_failed; } #if IS_ENABLED(CONFIG_MPLS) err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS); if (err < 0) { pr_info("%s: can't register tunnel\n", __func__); goto xfrm_tunnel_mplsip_failed; } #endif err = rtnl_link_register(&ipip_link_ops); if (err < 0) goto rtnl_link_failed; out: return err; rtnl_link_failed: #if IS_ENABLED(CONFIG_MPLS) xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS); xfrm_tunnel_mplsip_failed: #endif xfrm4_tunnel_deregister(&ipip_handler, AF_INET); xfrm_tunnel_ipip_failed: unregister_pernet_device(&ipip_net_ops); goto out; } static void __exit ipip_fini(void) { rtnl_link_unregister(&ipip_link_ops); if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET)) pr_info("%s: can't deregister tunnel\n", __func__); #if IS_ENABLED(CONFIG_MPLS) if (xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS)) pr_info("%s: can't deregister tunnel\n", __func__); #endif unregister_pernet_device(&ipip_net_ops); } module_init(ipip_init); module_exit(ipip_fini); MODULE_LICENSE("GPL"); MODULE_ALIAS_RTNL_LINK("ipip"); MODULE_ALIAS_NETDEV("tunl0");
linux-master
net/ipv4/ipip.c
// SPDX-License-Identifier: GPL-2.0-only /* * TCP Veno congestion control * * This is based on the congestion detection/avoidance scheme described in * C. P. Fu, S. C. Liew. * "TCP Veno: TCP Enhancement for Transmission over Wireless Access Networks." * IEEE Journal on Selected Areas in Communication, * Feb. 2003. * See https://www.ie.cuhk.edu.hk/fileadmin/staff_upload/soung/Journal/J3.pdf */ #include <linux/mm.h> #include <linux/module.h> #include <linux/skbuff.h> #include <linux/inet_diag.h> #include <net/tcp.h> /* Default values of the Veno variables, in fixed-point representation * with V_PARAM_SHIFT bits to the right of the binary point. */ #define V_PARAM_SHIFT 1 static const int beta = 3 << V_PARAM_SHIFT; /* Veno variables */ struct veno { u8 doing_veno_now; /* if true, do veno for this rtt */ u16 cntrtt; /* # of rtts measured within last rtt */ u32 minrtt; /* min of rtts measured within last rtt (in usec) */ u32 basertt; /* the min of all Veno rtt measurements seen (in usec) */ u32 inc; /* decide whether to increase cwnd */ u32 diff; /* calculate the diff rate */ }; /* There are several situations when we must "re-start" Veno: * * o when a connection is established * o after an RTO * o after fast recovery * o when we send a packet and there is no outstanding * unacknowledged data (restarting an idle connection) * */ static inline void veno_enable(struct sock *sk) { struct veno *veno = inet_csk_ca(sk); /* turn on Veno */ veno->doing_veno_now = 1; veno->minrtt = 0x7fffffff; } static inline void veno_disable(struct sock *sk) { struct veno *veno = inet_csk_ca(sk); /* turn off Veno */ veno->doing_veno_now = 0; } static void tcp_veno_init(struct sock *sk) { struct veno *veno = inet_csk_ca(sk); veno->basertt = 0x7fffffff; veno->inc = 1; veno_enable(sk); } /* Do rtt sampling needed for Veno. */ static void tcp_veno_pkts_acked(struct sock *sk, const struct ack_sample *sample) { struct veno *veno = inet_csk_ca(sk); u32 vrtt; if (sample->rtt_us < 0) return; /* Never allow zero rtt or baseRTT */ vrtt = sample->rtt_us + 1; /* Filter to find propagation delay: */ if (vrtt < veno->basertt) veno->basertt = vrtt; /* Find the min rtt during the last rtt to find * the current prop. delay + queuing delay: */ veno->minrtt = min(veno->minrtt, vrtt); veno->cntrtt++; } static void tcp_veno_state(struct sock *sk, u8 ca_state) { if (ca_state == TCP_CA_Open) veno_enable(sk); else veno_disable(sk); } /* * If the connection is idle and we are restarting, * then we don't want to do any Veno calculations * until we get fresh rtt samples. So when we * restart, we reset our Veno state to a clean * state. After we get acks for this flight of * packets, _then_ we can make Veno calculations * again. */ static void tcp_veno_cwnd_event(struct sock *sk, enum tcp_ca_event event) { if (event == CA_EVENT_CWND_RESTART || event == CA_EVENT_TX_START) tcp_veno_init(sk); } static void tcp_veno_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct veno *veno = inet_csk_ca(sk); if (!veno->doing_veno_now) { tcp_reno_cong_avoid(sk, ack, acked); return; } /* limited by applications */ if (!tcp_is_cwnd_limited(sk)) return; /* We do the Veno calculations only if we got enough rtt samples */ if (veno->cntrtt <= 2) { /* We don't have enough rtt samples to do the Veno * calculation, so we'll behave like Reno. */ tcp_reno_cong_avoid(sk, ack, acked); } else { u64 target_cwnd; u32 rtt; /* We have enough rtt samples, so, using the Veno * algorithm, we determine the state of the network. */ rtt = veno->minrtt; target_cwnd = (u64)tcp_snd_cwnd(tp) * veno->basertt; target_cwnd <<= V_PARAM_SHIFT; do_div(target_cwnd, rtt); veno->diff = (tcp_snd_cwnd(tp) << V_PARAM_SHIFT) - target_cwnd; if (tcp_in_slow_start(tp)) { /* Slow start. */ acked = tcp_slow_start(tp, acked); if (!acked) goto done; } /* Congestion avoidance. */ if (veno->diff < beta) { /* In the "non-congestive state", increase cwnd * every rtt. */ tcp_cong_avoid_ai(tp, tcp_snd_cwnd(tp), acked); } else { /* In the "congestive state", increase cwnd * every other rtt. */ if (tp->snd_cwnd_cnt >= tcp_snd_cwnd(tp)) { if (veno->inc && tcp_snd_cwnd(tp) < tp->snd_cwnd_clamp) { tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) + 1); veno->inc = 0; } else veno->inc = 1; tp->snd_cwnd_cnt = 0; } else tp->snd_cwnd_cnt += acked; } done: if (tcp_snd_cwnd(tp) < 2) tcp_snd_cwnd_set(tp, 2); else if (tcp_snd_cwnd(tp) > tp->snd_cwnd_clamp) tcp_snd_cwnd_set(tp, tp->snd_cwnd_clamp); } /* Wipe the slate clean for the next rtt. */ /* veno->cntrtt = 0; */ veno->minrtt = 0x7fffffff; } /* Veno MD phase */ static u32 tcp_veno_ssthresh(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct veno *veno = inet_csk_ca(sk); if (veno->diff < beta) /* in "non-congestive state", cut cwnd by 1/5 */ return max(tcp_snd_cwnd(tp) * 4 / 5, 2U); else /* in "congestive state", cut cwnd by 1/2 */ return max(tcp_snd_cwnd(tp) >> 1U, 2U); } static struct tcp_congestion_ops tcp_veno __read_mostly = { .init = tcp_veno_init, .ssthresh = tcp_veno_ssthresh, .undo_cwnd = tcp_reno_undo_cwnd, .cong_avoid = tcp_veno_cong_avoid, .pkts_acked = tcp_veno_pkts_acked, .set_state = tcp_veno_state, .cwnd_event = tcp_veno_cwnd_event, .owner = THIS_MODULE, .name = "veno", }; static int __init tcp_veno_register(void) { BUILD_BUG_ON(sizeof(struct veno) > ICSK_CA_PRIV_SIZE); tcp_register_congestion_control(&tcp_veno); return 0; } static void __exit tcp_veno_unregister(void) { tcp_unregister_congestion_control(&tcp_veno); } module_init(tcp_veno_register); module_exit(tcp_veno_unregister); MODULE_AUTHOR("Bin Zhou, Cheng Peng Fu"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("TCP Veno");
linux-master
net/ipv4/tcp_veno.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * IPv4 Forwarding Information Base: FIB frontend. * * Authors: Alexey Kuznetsov, <[email protected]> */ #include <linux/module.h> #include <linux/uaccess.h> #include <linux/bitops.h> #include <linux/capability.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/string.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/errno.h> #include <linux/in.h> #include <linux/inet.h> #include <linux/inetdevice.h> #include <linux/netdevice.h> #include <linux/if_addr.h> #include <linux/if_arp.h> #include <linux/skbuff.h> #include <linux/cache.h> #include <linux/init.h> #include <linux/list.h> #include <linux/slab.h> #include <net/inet_dscp.h> #include <net/ip.h> #include <net/protocol.h> #include <net/route.h> #include <net/tcp.h> #include <net/sock.h> #include <net/arp.h> #include <net/ip_fib.h> #include <net/nexthop.h> #include <net/rtnetlink.h> #include <net/xfrm.h> #include <net/l3mdev.h> #include <net/lwtunnel.h> #include <trace/events/fib.h> #ifndef CONFIG_IP_MULTIPLE_TABLES static int __net_init fib4_rules_init(struct net *net) { struct fib_table *local_table, *main_table; main_table = fib_trie_table(RT_TABLE_MAIN, NULL); if (!main_table) return -ENOMEM; local_table = fib_trie_table(RT_TABLE_LOCAL, main_table); if (!local_table) goto fail; hlist_add_head_rcu(&local_table->tb_hlist, &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]); hlist_add_head_rcu(&main_table->tb_hlist, &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]); return 0; fail: fib_free_table(main_table); return -ENOMEM; } #else struct fib_table *fib_new_table(struct net *net, u32 id) { struct fib_table *tb, *alias = NULL; unsigned int h; if (id == 0) id = RT_TABLE_MAIN; tb = fib_get_table(net, id); if (tb) return tb; if (id == RT_TABLE_LOCAL && !net->ipv4.fib_has_custom_rules) alias = fib_new_table(net, RT_TABLE_MAIN); tb = fib_trie_table(id, alias); if (!tb) return NULL; switch (id) { case RT_TABLE_MAIN: rcu_assign_pointer(net->ipv4.fib_main, tb); break; case RT_TABLE_DEFAULT: rcu_assign_pointer(net->ipv4.fib_default, tb); break; default: break; } h = id & (FIB_TABLE_HASHSZ - 1); hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]); return tb; } EXPORT_SYMBOL_GPL(fib_new_table); /* caller must hold either rtnl or rcu read lock */ struct fib_table *fib_get_table(struct net *net, u32 id) { struct fib_table *tb; struct hlist_head *head; unsigned int h; if (id == 0) id = RT_TABLE_MAIN; h = id & (FIB_TABLE_HASHSZ - 1); head = &net->ipv4.fib_table_hash[h]; hlist_for_each_entry_rcu(tb, head, tb_hlist, lockdep_rtnl_is_held()) { if (tb->tb_id == id) return tb; } return NULL; } #endif /* CONFIG_IP_MULTIPLE_TABLES */ static void fib_replace_table(struct net *net, struct fib_table *old, struct fib_table *new) { #ifdef CONFIG_IP_MULTIPLE_TABLES switch (new->tb_id) { case RT_TABLE_MAIN: rcu_assign_pointer(net->ipv4.fib_main, new); break; case RT_TABLE_DEFAULT: rcu_assign_pointer(net->ipv4.fib_default, new); break; default: break; } #endif /* replace the old table in the hlist */ hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist); } int fib_unmerge(struct net *net) { struct fib_table *old, *new, *main_table; /* attempt to fetch local table if it has been allocated */ old = fib_get_table(net, RT_TABLE_LOCAL); if (!old) return 0; new = fib_trie_unmerge(old); if (!new) return -ENOMEM; /* table is already unmerged */ if (new == old) return 0; /* replace merged table with clean table */ fib_replace_table(net, old, new); fib_free_table(old); /* attempt to fetch main table if it has been allocated */ main_table = fib_get_table(net, RT_TABLE_MAIN); if (!main_table) return 0; /* flush local entries from main table */ fib_table_flush_external(main_table); return 0; } void fib_flush(struct net *net) { int flushed = 0; unsigned int h; for (h = 0; h < FIB_TABLE_HASHSZ; h++) { struct hlist_head *head = &net->ipv4.fib_table_hash[h]; struct hlist_node *tmp; struct fib_table *tb; hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) flushed += fib_table_flush(net, tb, false); } if (flushed) rt_cache_flush(net); } /* * Find address type as if only "dev" was present in the system. If * on_dev is NULL then all interfaces are taken into consideration. */ static inline unsigned int __inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr, u32 tb_id) { struct flowi4 fl4 = { .daddr = addr }; struct fib_result res; unsigned int ret = RTN_BROADCAST; struct fib_table *table; if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr)) return RTN_BROADCAST; if (ipv4_is_multicast(addr)) return RTN_MULTICAST; rcu_read_lock(); table = fib_get_table(net, tb_id); if (table) { ret = RTN_UNICAST; if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) { struct fib_nh_common *nhc = fib_info_nhc(res.fi, 0); if (!dev || dev == nhc->nhc_dev) ret = res.type; } } rcu_read_unlock(); return ret; } unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id) { return __inet_dev_addr_type(net, NULL, addr, tb_id); } EXPORT_SYMBOL(inet_addr_type_table); unsigned int inet_addr_type(struct net *net, __be32 addr) { return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL); } EXPORT_SYMBOL(inet_addr_type); unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr) { u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL; return __inet_dev_addr_type(net, dev, addr, rt_table); } EXPORT_SYMBOL(inet_dev_addr_type); /* inet_addr_type with dev == NULL but using the table from a dev * if one is associated */ unsigned int inet_addr_type_dev_table(struct net *net, const struct net_device *dev, __be32 addr) { u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL; return __inet_dev_addr_type(net, NULL, addr, rt_table); } EXPORT_SYMBOL(inet_addr_type_dev_table); __be32 fib_compute_spec_dst(struct sk_buff *skb) { struct net_device *dev = skb->dev; struct in_device *in_dev; struct fib_result res; struct rtable *rt; struct net *net; int scope; rt = skb_rtable(skb); if ((rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | RTCF_LOCAL)) == RTCF_LOCAL) return ip_hdr(skb)->daddr; in_dev = __in_dev_get_rcu(dev); net = dev_net(dev); scope = RT_SCOPE_UNIVERSE; if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) { bool vmark = in_dev && IN_DEV_SRC_VMARK(in_dev); struct flowi4 fl4 = { .flowi4_iif = LOOPBACK_IFINDEX, .flowi4_l3mdev = l3mdev_master_ifindex_rcu(dev), .daddr = ip_hdr(skb)->saddr, .flowi4_tos = ip_hdr(skb)->tos & IPTOS_RT_MASK, .flowi4_scope = scope, .flowi4_mark = vmark ? skb->mark : 0, }; if (!fib_lookup(net, &fl4, &res, 0)) return fib_result_prefsrc(net, &res); } else { scope = RT_SCOPE_LINK; } return inet_select_addr(dev, ip_hdr(skb)->saddr, scope); } bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev) { bool dev_match = false; #ifdef CONFIG_IP_ROUTE_MULTIPATH if (unlikely(fi->nh)) { dev_match = nexthop_uses_dev(fi->nh, dev); } else { int ret; for (ret = 0; ret < fib_info_num_path(fi); ret++) { const struct fib_nh_common *nhc = fib_info_nhc(fi, ret); if (nhc_l3mdev_matches_dev(nhc, dev)) { dev_match = true; break; } } } #else if (fib_info_nhc(fi, 0)->nhc_dev == dev) dev_match = true; #endif return dev_match; } EXPORT_SYMBOL_GPL(fib_info_nh_uses_dev); /* Given (packet source, input interface) and optional (dst, oif, tos): * - (main) check, that source is valid i.e. not broadcast or our local * address. * - figure out what "logical" interface this packet arrived * and calculate "specific destination" address. * - check, that packet arrived from expected physical interface. * called with rcu_read_lock() */ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, u8 tos, int oif, struct net_device *dev, int rpf, struct in_device *idev, u32 *itag) { struct net *net = dev_net(dev); struct flow_keys flkeys; int ret, no_addr; struct fib_result res; struct flowi4 fl4; bool dev_match; fl4.flowi4_oif = 0; fl4.flowi4_l3mdev = l3mdev_master_ifindex_rcu(dev); fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX; fl4.daddr = src; fl4.saddr = dst; fl4.flowi4_tos = tos; fl4.flowi4_scope = RT_SCOPE_UNIVERSE; fl4.flowi4_tun_key.tun_id = 0; fl4.flowi4_flags = 0; fl4.flowi4_uid = sock_net_uid(net, NULL); fl4.flowi4_multipath_hash = 0; no_addr = idev->ifa_list == NULL; fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0; if (!fib4_rules_early_flow_dissect(net, skb, &fl4, &flkeys)) { fl4.flowi4_proto = 0; fl4.fl4_sport = 0; fl4.fl4_dport = 0; } else { swap(fl4.fl4_sport, fl4.fl4_dport); } if (fib_lookup(net, &fl4, &res, 0)) goto last_resort; if (res.type != RTN_UNICAST && (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev))) goto e_inval; fib_combine_itag(itag, &res); dev_match = fib_info_nh_uses_dev(res.fi, dev); /* This is not common, loopback packets retain skb_dst so normally they * would not even hit this slow path. */ dev_match = dev_match || (res.type == RTN_LOCAL && dev == net->loopback_dev); if (dev_match) { ret = FIB_RES_NHC(res)->nhc_scope >= RT_SCOPE_HOST; return ret; } if (no_addr) goto last_resort; if (rpf == 1) goto e_rpf; fl4.flowi4_oif = dev->ifindex; ret = 0; if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) { if (res.type == RTN_UNICAST) ret = FIB_RES_NHC(res)->nhc_scope >= RT_SCOPE_HOST; } return ret; last_resort: if (rpf) goto e_rpf; *itag = 0; return 0; e_inval: return -EINVAL; e_rpf: return -EXDEV; } /* Ignore rp_filter for packets protected by IPsec. */ int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, u8 tos, int oif, struct net_device *dev, struct in_device *idev, u32 *itag) { int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev); struct net *net = dev_net(dev); if (!r && !fib_num_tclassid_users(net) && (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) { if (IN_DEV_ACCEPT_LOCAL(idev)) goto ok; /* with custom local routes in place, checking local addresses * only will be too optimistic, with custom rules, checking * local addresses only can be too strict, e.g. due to vrf */ if (net->ipv4.fib_has_custom_local_routes || fib4_has_custom_rules(net)) goto full_check; /* Within the same container, it is regarded as a martian source, * and the same host but different containers are not. */ if (inet_lookup_ifaddr_rcu(net, src)) return -EINVAL; ok: *itag = 0; return 0; } full_check: return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag); } static inline __be32 sk_extract_addr(struct sockaddr *addr) { return ((struct sockaddr_in *) addr)->sin_addr.s_addr; } static int put_rtax(struct nlattr *mx, int len, int type, u32 value) { struct nlattr *nla; nla = (struct nlattr *) ((char *) mx + len); nla->nla_type = type; nla->nla_len = nla_attr_size(4); *(u32 *) nla_data(nla) = value; return len + nla_total_size(4); } static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt, struct fib_config *cfg) { __be32 addr; int plen; memset(cfg, 0, sizeof(*cfg)); cfg->fc_nlinfo.nl_net = net; if (rt->rt_dst.sa_family != AF_INET) return -EAFNOSUPPORT; /* * Check mask for validity: * a) it must be contiguous. * b) destination must have all host bits clear. * c) if application forgot to set correct family (AF_INET), * reject request unless it is absolutely clear i.e. * both family and mask are zero. */ plen = 32; addr = sk_extract_addr(&rt->rt_dst); if (!(rt->rt_flags & RTF_HOST)) { __be32 mask = sk_extract_addr(&rt->rt_genmask); if (rt->rt_genmask.sa_family != AF_INET) { if (mask || rt->rt_genmask.sa_family) return -EAFNOSUPPORT; } if (bad_mask(mask, addr)) return -EINVAL; plen = inet_mask_len(mask); } cfg->fc_dst_len = plen; cfg->fc_dst = addr; if (cmd != SIOCDELRT) { cfg->fc_nlflags = NLM_F_CREATE; cfg->fc_protocol = RTPROT_BOOT; } if (rt->rt_metric) cfg->fc_priority = rt->rt_metric - 1; if (rt->rt_flags & RTF_REJECT) { cfg->fc_scope = RT_SCOPE_HOST; cfg->fc_type = RTN_UNREACHABLE; return 0; } cfg->fc_scope = RT_SCOPE_NOWHERE; cfg->fc_type = RTN_UNICAST; if (rt->rt_dev) { char *colon; struct net_device *dev; char devname[IFNAMSIZ]; if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1)) return -EFAULT; devname[IFNAMSIZ-1] = 0; colon = strchr(devname, ':'); if (colon) *colon = 0; dev = __dev_get_by_name(net, devname); if (!dev) return -ENODEV; cfg->fc_oif = dev->ifindex; cfg->fc_table = l3mdev_fib_table(dev); if (colon) { const struct in_ifaddr *ifa; struct in_device *in_dev; in_dev = __in_dev_get_rtnl(dev); if (!in_dev) return -ENODEV; *colon = ':'; rcu_read_lock(); in_dev_for_each_ifa_rcu(ifa, in_dev) { if (strcmp(ifa->ifa_label, devname) == 0) break; } rcu_read_unlock(); if (!ifa) return -ENODEV; cfg->fc_prefsrc = ifa->ifa_local; } } addr = sk_extract_addr(&rt->rt_gateway); if (rt->rt_gateway.sa_family == AF_INET && addr) { unsigned int addr_type; cfg->fc_gw4 = addr; cfg->fc_gw_family = AF_INET; addr_type = inet_addr_type_table(net, addr, cfg->fc_table); if (rt->rt_flags & RTF_GATEWAY && addr_type == RTN_UNICAST) cfg->fc_scope = RT_SCOPE_UNIVERSE; } if (!cfg->fc_table) cfg->fc_table = RT_TABLE_MAIN; if (cmd == SIOCDELRT) return 0; if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw_family) return -EINVAL; if (cfg->fc_scope == RT_SCOPE_NOWHERE) cfg->fc_scope = RT_SCOPE_LINK; if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) { struct nlattr *mx; int len = 0; mx = kcalloc(3, nla_total_size(4), GFP_KERNEL); if (!mx) return -ENOMEM; if (rt->rt_flags & RTF_MTU) len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40); if (rt->rt_flags & RTF_WINDOW) len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window); if (rt->rt_flags & RTF_IRTT) len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3); cfg->fc_mx = mx; cfg->fc_mx_len = len; } return 0; } /* * Handle IP routing ioctl calls. * These are used to manipulate the routing tables */ int ip_rt_ioctl(struct net *net, unsigned int cmd, struct rtentry *rt) { struct fib_config cfg; int err; switch (cmd) { case SIOCADDRT: /* Add a route */ case SIOCDELRT: /* Delete a route */ if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) return -EPERM; rtnl_lock(); err = rtentry_to_fib_config(net, cmd, rt, &cfg); if (err == 0) { struct fib_table *tb; if (cmd == SIOCDELRT) { tb = fib_get_table(net, cfg.fc_table); if (tb) err = fib_table_delete(net, tb, &cfg, NULL); else err = -ESRCH; } else { tb = fib_new_table(net, cfg.fc_table); if (tb) err = fib_table_insert(net, tb, &cfg, NULL); else err = -ENOBUFS; } /* allocated by rtentry_to_fib_config() */ kfree(cfg.fc_mx); } rtnl_unlock(); return err; } return -EINVAL; } const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = { [RTA_UNSPEC] = { .strict_start_type = RTA_DPORT + 1 }, [RTA_DST] = { .type = NLA_U32 }, [RTA_SRC] = { .type = NLA_U32 }, [RTA_IIF] = { .type = NLA_U32 }, [RTA_OIF] = { .type = NLA_U32 }, [RTA_GATEWAY] = { .type = NLA_U32 }, [RTA_PRIORITY] = { .type = NLA_U32 }, [RTA_PREFSRC] = { .type = NLA_U32 }, [RTA_METRICS] = { .type = NLA_NESTED }, [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, [RTA_FLOW] = { .type = NLA_U32 }, [RTA_ENCAP_TYPE] = { .type = NLA_U16 }, [RTA_ENCAP] = { .type = NLA_NESTED }, [RTA_UID] = { .type = NLA_U32 }, [RTA_MARK] = { .type = NLA_U32 }, [RTA_TABLE] = { .type = NLA_U32 }, [RTA_IP_PROTO] = { .type = NLA_U8 }, [RTA_SPORT] = { .type = NLA_U16 }, [RTA_DPORT] = { .type = NLA_U16 }, [RTA_NH_ID] = { .type = NLA_U32 }, }; int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla, struct netlink_ext_ack *extack) { struct rtvia *via; int alen; if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) { NL_SET_ERR_MSG(extack, "Invalid attribute length for RTA_VIA"); return -EINVAL; } via = nla_data(nla); alen = nla_len(nla) - offsetof(struct rtvia, rtvia_addr); switch (via->rtvia_family) { case AF_INET: if (alen != sizeof(__be32)) { NL_SET_ERR_MSG(extack, "Invalid IPv4 address in RTA_VIA"); return -EINVAL; } cfg->fc_gw_family = AF_INET; cfg->fc_gw4 = *((__be32 *)via->rtvia_addr); break; case AF_INET6: #if IS_ENABLED(CONFIG_IPV6) if (alen != sizeof(struct in6_addr)) { NL_SET_ERR_MSG(extack, "Invalid IPv6 address in RTA_VIA"); return -EINVAL; } cfg->fc_gw_family = AF_INET6; cfg->fc_gw6 = *((struct in6_addr *)via->rtvia_addr); #else NL_SET_ERR_MSG(extack, "IPv6 support not enabled in kernel"); return -EINVAL; #endif break; default: NL_SET_ERR_MSG(extack, "Unsupported address family in RTA_VIA"); return -EINVAL; } return 0; } static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh, struct fib_config *cfg, struct netlink_ext_ack *extack) { bool has_gw = false, has_via = false; struct nlattr *attr; int err, remaining; struct rtmsg *rtm; err = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy, extack); if (err < 0) goto errout; memset(cfg, 0, sizeof(*cfg)); rtm = nlmsg_data(nlh); if (!inet_validate_dscp(rtm->rtm_tos)) { NL_SET_ERR_MSG(extack, "Invalid dsfield (tos): ECN bits must be 0"); err = -EINVAL; goto errout; } cfg->fc_dscp = inet_dsfield_to_dscp(rtm->rtm_tos); cfg->fc_dst_len = rtm->rtm_dst_len; cfg->fc_table = rtm->rtm_table; cfg->fc_protocol = rtm->rtm_protocol; cfg->fc_scope = rtm->rtm_scope; cfg->fc_type = rtm->rtm_type; cfg->fc_flags = rtm->rtm_flags; cfg->fc_nlflags = nlh->nlmsg_flags; cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid; cfg->fc_nlinfo.nlh = nlh; cfg->fc_nlinfo.nl_net = net; if (cfg->fc_type > RTN_MAX) { NL_SET_ERR_MSG(extack, "Invalid route type"); err = -EINVAL; goto errout; } nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) { switch (nla_type(attr)) { case RTA_DST: cfg->fc_dst = nla_get_be32(attr); break; case RTA_OIF: cfg->fc_oif = nla_get_u32(attr); break; case RTA_GATEWAY: has_gw = true; cfg->fc_gw4 = nla_get_be32(attr); if (cfg->fc_gw4) cfg->fc_gw_family = AF_INET; break; case RTA_VIA: has_via = true; err = fib_gw_from_via(cfg, attr, extack); if (err) goto errout; break; case RTA_PRIORITY: cfg->fc_priority = nla_get_u32(attr); break; case RTA_PREFSRC: cfg->fc_prefsrc = nla_get_be32(attr); break; case RTA_METRICS: cfg->fc_mx = nla_data(attr); cfg->fc_mx_len = nla_len(attr); break; case RTA_MULTIPATH: err = lwtunnel_valid_encap_type_attr(nla_data(attr), nla_len(attr), extack); if (err < 0) goto errout; cfg->fc_mp = nla_data(attr); cfg->fc_mp_len = nla_len(attr); break; case RTA_FLOW: cfg->fc_flow = nla_get_u32(attr); break; case RTA_TABLE: cfg->fc_table = nla_get_u32(attr); break; case RTA_ENCAP: cfg->fc_encap = attr; break; case RTA_ENCAP_TYPE: cfg->fc_encap_type = nla_get_u16(attr); err = lwtunnel_valid_encap_type(cfg->fc_encap_type, extack); if (err < 0) goto errout; break; case RTA_NH_ID: cfg->fc_nh_id = nla_get_u32(attr); break; } } if (cfg->fc_nh_id) { if (cfg->fc_oif || cfg->fc_gw_family || cfg->fc_encap || cfg->fc_mp) { NL_SET_ERR_MSG(extack, "Nexthop specification and nexthop id are mutually exclusive"); return -EINVAL; } } if (has_gw && has_via) { NL_SET_ERR_MSG(extack, "Nexthop configuration can not contain both GATEWAY and VIA"); return -EINVAL; } if (!cfg->fc_table) cfg->fc_table = RT_TABLE_MAIN; return 0; errout: return err; } static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct fib_config cfg; struct fib_table *tb; int err; err = rtm_to_fib_config(net, skb, nlh, &cfg, extack); if (err < 0) goto errout; if (cfg.fc_nh_id && !nexthop_find_by_id(net, cfg.fc_nh_id)) { NL_SET_ERR_MSG(extack, "Nexthop id does not exist"); err = -EINVAL; goto errout; } tb = fib_get_table(net, cfg.fc_table); if (!tb) { NL_SET_ERR_MSG(extack, "FIB table does not exist"); err = -ESRCH; goto errout; } err = fib_table_delete(net, tb, &cfg, extack); errout: return err; } static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct fib_config cfg; struct fib_table *tb; int err; err = rtm_to_fib_config(net, skb, nlh, &cfg, extack); if (err < 0) goto errout; tb = fib_new_table(net, cfg.fc_table); if (!tb) { err = -ENOBUFS; goto errout; } err = fib_table_insert(net, tb, &cfg, extack); if (!err && cfg.fc_type == RTN_LOCAL) net->ipv4.fib_has_custom_local_routes = true; errout: return err; } int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, struct fib_dump_filter *filter, struct netlink_callback *cb) { struct netlink_ext_ack *extack = cb->extack; struct nlattr *tb[RTA_MAX + 1]; struct rtmsg *rtm; int err, i; ASSERT_RTNL(); if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) { NL_SET_ERR_MSG(extack, "Invalid header for FIB dump request"); return -EINVAL; } rtm = nlmsg_data(nlh); if (rtm->rtm_dst_len || rtm->rtm_src_len || rtm->rtm_tos || rtm->rtm_scope) { NL_SET_ERR_MSG(extack, "Invalid values in header for FIB dump request"); return -EINVAL; } if (rtm->rtm_flags & ~(RTM_F_CLONED | RTM_F_PREFIX)) { NL_SET_ERR_MSG(extack, "Invalid flags for FIB dump request"); return -EINVAL; } if (rtm->rtm_flags & RTM_F_CLONED) filter->dump_routes = false; else filter->dump_exceptions = false; filter->flags = rtm->rtm_flags; filter->protocol = rtm->rtm_protocol; filter->rt_type = rtm->rtm_type; filter->table_id = rtm->rtm_table; err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy, extack); if (err < 0) return err; for (i = 0; i <= RTA_MAX; ++i) { int ifindex; if (!tb[i]) continue; switch (i) { case RTA_TABLE: filter->table_id = nla_get_u32(tb[i]); break; case RTA_OIF: ifindex = nla_get_u32(tb[i]); filter->dev = __dev_get_by_index(net, ifindex); if (!filter->dev) return -ENODEV; break; default: NL_SET_ERR_MSG(extack, "Unsupported attribute in dump request"); return -EINVAL; } } if (filter->flags || filter->protocol || filter->rt_type || filter->table_id || filter->dev) { filter->filter_set = 1; cb->answer_flags = NLM_F_DUMP_FILTERED; } return 0; } EXPORT_SYMBOL_GPL(ip_valid_fib_dump_req); static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) { struct fib_dump_filter filter = { .dump_routes = true, .dump_exceptions = true }; const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); unsigned int h, s_h; unsigned int e = 0, s_e; struct fib_table *tb; struct hlist_head *head; int dumped = 0, err; if (cb->strict_check) { err = ip_valid_fib_dump_req(net, nlh, &filter, cb); if (err < 0) return err; } else if (nlmsg_len(nlh) >= sizeof(struct rtmsg)) { struct rtmsg *rtm = nlmsg_data(nlh); filter.flags = rtm->rtm_flags & (RTM_F_PREFIX | RTM_F_CLONED); } /* ipv4 does not use prefix flag */ if (filter.flags & RTM_F_PREFIX) return skb->len; if (filter.table_id) { tb = fib_get_table(net, filter.table_id); if (!tb) { if (rtnl_msg_family(cb->nlh) != PF_INET) return skb->len; NL_SET_ERR_MSG(cb->extack, "ipv4: FIB table does not exist"); return -ENOENT; } rcu_read_lock(); err = fib_table_dump(tb, skb, cb, &filter); rcu_read_unlock(); return skb->len ? : err; } s_h = cb->args[0]; s_e = cb->args[1]; rcu_read_lock(); for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { e = 0; head = &net->ipv4.fib_table_hash[h]; hlist_for_each_entry_rcu(tb, head, tb_hlist) { if (e < s_e) goto next; if (dumped) memset(&cb->args[2], 0, sizeof(cb->args) - 2 * sizeof(cb->args[0])); err = fib_table_dump(tb, skb, cb, &filter); if (err < 0) { if (likely(skb->len)) goto out; goto out_err; } dumped = 1; next: e++; } } out: err = skb->len; out_err: rcu_read_unlock(); cb->args[1] = e; cb->args[0] = h; return err; } /* Prepare and feed intra-kernel routing request. * Really, it should be netlink message, but :-( netlink * can be not configured, so that we feed it directly * to fib engine. It is legal, because all events occur * only when netlink is already locked. */ static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa, u32 rt_priority) { struct net *net = dev_net(ifa->ifa_dev->dev); u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev); struct fib_table *tb; struct fib_config cfg = { .fc_protocol = RTPROT_KERNEL, .fc_type = type, .fc_dst = dst, .fc_dst_len = dst_len, .fc_priority = rt_priority, .fc_prefsrc = ifa->ifa_local, .fc_oif = ifa->ifa_dev->dev->ifindex, .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND, .fc_nlinfo = { .nl_net = net, }, }; if (!tb_id) tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL; tb = fib_new_table(net, tb_id); if (!tb) return; cfg.fc_table = tb->tb_id; if (type != RTN_LOCAL) cfg.fc_scope = RT_SCOPE_LINK; else cfg.fc_scope = RT_SCOPE_HOST; if (cmd == RTM_NEWROUTE) fib_table_insert(net, tb, &cfg, NULL); else fib_table_delete(net, tb, &cfg, NULL); } void fib_add_ifaddr(struct in_ifaddr *ifa) { struct in_device *in_dev = ifa->ifa_dev; struct net_device *dev = in_dev->dev; struct in_ifaddr *prim = ifa; __be32 mask = ifa->ifa_mask; __be32 addr = ifa->ifa_local; __be32 prefix = ifa->ifa_address & mask; if (ifa->ifa_flags & IFA_F_SECONDARY) { prim = inet_ifa_byprefix(in_dev, prefix, mask); if (!prim) { pr_warn("%s: bug: prim == NULL\n", __func__); return; } } fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim, 0); if (!(dev->flags & IFF_UP)) return; /* Add broadcast address, if it is explicitly assigned. */ if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF)) { fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim, 0); arp_invalidate(dev, ifa->ifa_broadcast, false); } if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) && (prefix != addr || ifa->ifa_prefixlen < 32)) { if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) fib_magic(RTM_NEWROUTE, dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, prefix, ifa->ifa_prefixlen, prim, ifa->ifa_rt_priority); /* Add the network broadcast address, when it makes sense */ if (ifa->ifa_prefixlen < 31) { fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask, 32, prim, 0); arp_invalidate(dev, prefix | ~mask, false); } } } void fib_modify_prefix_metric(struct in_ifaddr *ifa, u32 new_metric) { __be32 prefix = ifa->ifa_address & ifa->ifa_mask; struct in_device *in_dev = ifa->ifa_dev; struct net_device *dev = in_dev->dev; if (!(dev->flags & IFF_UP) || ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) || ipv4_is_zeronet(prefix) || (prefix == ifa->ifa_local && ifa->ifa_prefixlen == 32)) return; /* add the new */ fib_magic(RTM_NEWROUTE, dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, prefix, ifa->ifa_prefixlen, ifa, new_metric); /* delete the old */ fib_magic(RTM_DELROUTE, dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, prefix, ifa->ifa_prefixlen, ifa, ifa->ifa_rt_priority); } /* Delete primary or secondary address. * Optionally, on secondary address promotion consider the addresses * from subnet iprim as deleted, even if they are in device list. * In this case the secondary ifa can be in device list. */ void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim) { struct in_device *in_dev = ifa->ifa_dev; struct net_device *dev = in_dev->dev; struct in_ifaddr *ifa1; struct in_ifaddr *prim = ifa, *prim1 = NULL; __be32 brd = ifa->ifa_address | ~ifa->ifa_mask; __be32 any = ifa->ifa_address & ifa->ifa_mask; #define LOCAL_OK 1 #define BRD_OK 2 #define BRD0_OK 4 #define BRD1_OK 8 unsigned int ok = 0; int subnet = 0; /* Primary network */ int gone = 1; /* Address is missing */ int same_prefsrc = 0; /* Another primary with same IP */ if (ifa->ifa_flags & IFA_F_SECONDARY) { prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask); if (!prim) { /* if the device has been deleted, we don't perform * address promotion */ if (!in_dev->dead) pr_warn("%s: bug: prim == NULL\n", __func__); return; } if (iprim && iprim != prim) { pr_warn("%s: bug: iprim != prim\n", __func__); return; } } else if (!ipv4_is_zeronet(any) && (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) { if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) fib_magic(RTM_DELROUTE, dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, any, ifa->ifa_prefixlen, prim, 0); subnet = 1; } if (in_dev->dead) goto no_promotions; /* Deletion is more complicated than add. * We should take care of not to delete too much :-) * * Scan address list to be sure that addresses are really gone. */ rcu_read_lock(); in_dev_for_each_ifa_rcu(ifa1, in_dev) { if (ifa1 == ifa) { /* promotion, keep the IP */ gone = 0; continue; } /* Ignore IFAs from our subnet */ if (iprim && ifa1->ifa_mask == iprim->ifa_mask && inet_ifa_match(ifa1->ifa_address, iprim)) continue; /* Ignore ifa1 if it uses different primary IP (prefsrc) */ if (ifa1->ifa_flags & IFA_F_SECONDARY) { /* Another address from our subnet? */ if (ifa1->ifa_mask == prim->ifa_mask && inet_ifa_match(ifa1->ifa_address, prim)) prim1 = prim; else { /* We reached the secondaries, so * same_prefsrc should be determined. */ if (!same_prefsrc) continue; /* Search new prim1 if ifa1 is not * using the current prim1 */ if (!prim1 || ifa1->ifa_mask != prim1->ifa_mask || !inet_ifa_match(ifa1->ifa_address, prim1)) prim1 = inet_ifa_byprefix(in_dev, ifa1->ifa_address, ifa1->ifa_mask); if (!prim1) continue; if (prim1->ifa_local != prim->ifa_local) continue; } } else { if (prim->ifa_local != ifa1->ifa_local) continue; prim1 = ifa1; if (prim != prim1) same_prefsrc = 1; } if (ifa->ifa_local == ifa1->ifa_local) ok |= LOCAL_OK; if (ifa->ifa_broadcast == ifa1->ifa_broadcast) ok |= BRD_OK; if (brd == ifa1->ifa_broadcast) ok |= BRD1_OK; if (any == ifa1->ifa_broadcast) ok |= BRD0_OK; /* primary has network specific broadcasts */ if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) { __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask; __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask; if (!ipv4_is_zeronet(any1)) { if (ifa->ifa_broadcast == brd1 || ifa->ifa_broadcast == any1) ok |= BRD_OK; if (brd == brd1 || brd == any1) ok |= BRD1_OK; if (any == brd1 || any == any1) ok |= BRD0_OK; } } } rcu_read_unlock(); no_promotions: if (!(ok & BRD_OK)) fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim, 0); if (subnet && ifa->ifa_prefixlen < 31) { if (!(ok & BRD1_OK)) fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim, 0); if (!(ok & BRD0_OK)) fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim, 0); } if (!(ok & LOCAL_OK)) { unsigned int addr_type; fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim, 0); /* Check, that this local address finally disappeared. */ addr_type = inet_addr_type_dev_table(dev_net(dev), dev, ifa->ifa_local); if (gone && addr_type != RTN_LOCAL) { /* And the last, but not the least thing. * We must flush stray FIB entries. * * First of all, we scan fib_info list searching * for stray nexthop entries, then ignite fib_flush. */ if (fib_sync_down_addr(dev, ifa->ifa_local)) fib_flush(dev_net(dev)); } } #undef LOCAL_OK #undef BRD_OK #undef BRD0_OK #undef BRD1_OK } static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn) { struct fib_result res; struct flowi4 fl4 = { .flowi4_mark = frn->fl_mark, .daddr = frn->fl_addr, .flowi4_tos = frn->fl_tos, .flowi4_scope = frn->fl_scope, }; struct fib_table *tb; rcu_read_lock(); tb = fib_get_table(net, frn->tb_id_in); frn->err = -ENOENT; if (tb) { local_bh_disable(); frn->tb_id = tb->tb_id; frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF); if (!frn->err) { frn->prefixlen = res.prefixlen; frn->nh_sel = res.nh_sel; frn->type = res.type; frn->scope = res.scope; } local_bh_enable(); } rcu_read_unlock(); } static void nl_fib_input(struct sk_buff *skb) { struct net *net; struct fib_result_nl *frn; struct nlmsghdr *nlh; u32 portid; net = sock_net(skb->sk); nlh = nlmsg_hdr(skb); if (skb->len < nlmsg_total_size(sizeof(*frn)) || skb->len < nlh->nlmsg_len || nlmsg_len(nlh) < sizeof(*frn)) return; skb = netlink_skb_clone(skb, GFP_KERNEL); if (!skb) return; nlh = nlmsg_hdr(skb); frn = nlmsg_data(nlh); nl_fib_lookup(net, frn); portid = NETLINK_CB(skb).portid; /* netlink portid */ NETLINK_CB(skb).portid = 0; /* from kernel */ NETLINK_CB(skb).dst_group = 0; /* unicast */ nlmsg_unicast(net->ipv4.fibnl, skb, portid); } static int __net_init nl_fib_lookup_init(struct net *net) { struct sock *sk; struct netlink_kernel_cfg cfg = { .input = nl_fib_input, }; sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg); if (!sk) return -EAFNOSUPPORT; net->ipv4.fibnl = sk; return 0; } static void nl_fib_lookup_exit(struct net *net) { netlink_kernel_release(net->ipv4.fibnl); net->ipv4.fibnl = NULL; } static void fib_disable_ip(struct net_device *dev, unsigned long event, bool force) { if (fib_sync_down_dev(dev, event, force)) fib_flush(dev_net(dev)); else rt_cache_flush(dev_net(dev)); arp_ifdown(dev); } static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr) { struct in_ifaddr *ifa = ptr; struct net_device *dev = ifa->ifa_dev->dev; struct net *net = dev_net(dev); switch (event) { case NETDEV_UP: fib_add_ifaddr(ifa); #ifdef CONFIG_IP_ROUTE_MULTIPATH fib_sync_up(dev, RTNH_F_DEAD); #endif atomic_inc(&net->ipv4.dev_addr_genid); rt_cache_flush(dev_net(dev)); break; case NETDEV_DOWN: fib_del_ifaddr(ifa, NULL); atomic_inc(&net->ipv4.dev_addr_genid); if (!ifa->ifa_dev->ifa_list) { /* Last address was deleted from this interface. * Disable IP. */ fib_disable_ip(dev, event, true); } else { rt_cache_flush(dev_net(dev)); } break; } return NOTIFY_DONE; } static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct netdev_notifier_changeupper_info *upper_info = ptr; struct netdev_notifier_info_ext *info_ext = ptr; struct in_device *in_dev; struct net *net = dev_net(dev); struct in_ifaddr *ifa; unsigned int flags; if (event == NETDEV_UNREGISTER) { fib_disable_ip(dev, event, true); rt_flush_dev(dev); return NOTIFY_DONE; } in_dev = __in_dev_get_rtnl(dev); if (!in_dev) return NOTIFY_DONE; switch (event) { case NETDEV_UP: in_dev_for_each_ifa_rtnl(ifa, in_dev) { fib_add_ifaddr(ifa); } #ifdef CONFIG_IP_ROUTE_MULTIPATH fib_sync_up(dev, RTNH_F_DEAD); #endif atomic_inc(&net->ipv4.dev_addr_genid); rt_cache_flush(net); break; case NETDEV_DOWN: fib_disable_ip(dev, event, false); break; case NETDEV_CHANGE: flags = dev_get_flags(dev); if (flags & (IFF_RUNNING | IFF_LOWER_UP)) fib_sync_up(dev, RTNH_F_LINKDOWN); else fib_sync_down_dev(dev, event, false); rt_cache_flush(net); break; case NETDEV_CHANGEMTU: fib_sync_mtu(dev, info_ext->ext.mtu); rt_cache_flush(net); break; case NETDEV_CHANGEUPPER: upper_info = ptr; /* flush all routes if dev is linked to or unlinked from * an L3 master device (e.g., VRF) */ if (upper_info->upper_dev && netif_is_l3_master(upper_info->upper_dev)) fib_disable_ip(dev, NETDEV_DOWN, true); break; } return NOTIFY_DONE; } static struct notifier_block fib_inetaddr_notifier = { .notifier_call = fib_inetaddr_event, }; static struct notifier_block fib_netdev_notifier = { .notifier_call = fib_netdev_event, }; static int __net_init ip_fib_net_init(struct net *net) { int err; size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ; err = fib4_notifier_init(net); if (err) return err; #ifdef CONFIG_IP_ROUTE_MULTIPATH /* Default to 3-tuple */ net->ipv4.sysctl_fib_multipath_hash_fields = FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK; #endif /* Avoid false sharing : Use at least a full cache line */ size = max_t(size_t, size, L1_CACHE_BYTES); net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL); if (!net->ipv4.fib_table_hash) { err = -ENOMEM; goto err_table_hash_alloc; } err = fib4_rules_init(net); if (err < 0) goto err_rules_init; return 0; err_rules_init: kfree(net->ipv4.fib_table_hash); err_table_hash_alloc: fib4_notifier_exit(net); return err; } static void ip_fib_net_exit(struct net *net) { int i; ASSERT_RTNL(); #ifdef CONFIG_IP_MULTIPLE_TABLES RCU_INIT_POINTER(net->ipv4.fib_main, NULL); RCU_INIT_POINTER(net->ipv4.fib_default, NULL); #endif /* Destroy the tables in reverse order to guarantee that the * local table, ID 255, is destroyed before the main table, ID * 254. This is necessary as the local table may contain * references to data contained in the main table. */ for (i = FIB_TABLE_HASHSZ - 1; i >= 0; i--) { struct hlist_head *head = &net->ipv4.fib_table_hash[i]; struct hlist_node *tmp; struct fib_table *tb; hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) { hlist_del(&tb->tb_hlist); fib_table_flush(net, tb, true); fib_free_table(tb); } } #ifdef CONFIG_IP_MULTIPLE_TABLES fib4_rules_exit(net); #endif kfree(net->ipv4.fib_table_hash); fib4_notifier_exit(net); } static int __net_init fib_net_init(struct net *net) { int error; #ifdef CONFIG_IP_ROUTE_CLASSID atomic_set(&net->ipv4.fib_num_tclassid_users, 0); #endif error = ip_fib_net_init(net); if (error < 0) goto out; error = nl_fib_lookup_init(net); if (error < 0) goto out_nlfl; error = fib_proc_init(net); if (error < 0) goto out_proc; out: return error; out_proc: nl_fib_lookup_exit(net); out_nlfl: rtnl_lock(); ip_fib_net_exit(net); rtnl_unlock(); goto out; } static void __net_exit fib_net_exit(struct net *net) { fib_proc_exit(net); nl_fib_lookup_exit(net); } static void __net_exit fib_net_exit_batch(struct list_head *net_list) { struct net *net; rtnl_lock(); list_for_each_entry(net, net_list, exit_list) ip_fib_net_exit(net); rtnl_unlock(); } static struct pernet_operations fib_net_ops = { .init = fib_net_init, .exit = fib_net_exit, .exit_batch = fib_net_exit_batch, }; void __init ip_fib_init(void) { fib_trie_init(); register_pernet_subsys(&fib_net_ops); register_netdevice_notifier(&fib_netdev_notifier); register_inetaddr_notifier(&fib_inetaddr_notifier); rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, 0); rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, 0); rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, 0); }
linux-master
net/ipv4/fib_frontend.c
// SPDX-License-Identifier: GPL-2.0-only /* * TCP Westwood+: end-to-end bandwidth estimation for TCP * * Angelo Dell'Aera: author of the first version of TCP Westwood+ in Linux 2.4 * * Support at http://c3lab.poliba.it/index.php/Westwood * Main references in literature: * * - Mascolo S, Casetti, M. Gerla et al. * "TCP Westwood: bandwidth estimation for TCP" Proc. ACM Mobicom 2001 * * - A. Grieco, s. Mascolo * "Performance evaluation of New Reno, Vegas, Westwood+ TCP" ACM Computer * Comm. Review, 2004 * * - A. Dell'Aera, L. Grieco, S. Mascolo. * "Linux 2.4 Implementation of Westwood+ TCP with Rate-Halving : * A Performance Evaluation Over the Internet" (ICC 2004), Paris, June 2004 * * Westwood+ employs end-to-end bandwidth measurement to set cwnd and * ssthresh after packet loss. The probing phase is as the original Reno. */ #include <linux/mm.h> #include <linux/module.h> #include <linux/skbuff.h> #include <linux/inet_diag.h> #include <net/tcp.h> /* TCP Westwood structure */ struct westwood { u32 bw_ns_est; /* first bandwidth estimation..not too smoothed 8) */ u32 bw_est; /* bandwidth estimate */ u32 rtt_win_sx; /* here starts a new evaluation... */ u32 bk; u32 snd_una; /* used for evaluating the number of acked bytes */ u32 cumul_ack; u32 accounted; u32 rtt; u32 rtt_min; /* minimum observed RTT */ u8 first_ack; /* flag which infers that this is the first ack */ u8 reset_rtt_min; /* Reset RTT min to next RTT sample*/ }; /* TCP Westwood functions and constants */ #define TCP_WESTWOOD_RTT_MIN (HZ/20) /* 50ms */ #define TCP_WESTWOOD_INIT_RTT (20*HZ) /* maybe too conservative?! */ /* * @tcp_westwood_create * This function initializes fields used in TCP Westwood+, * it is called after the initial SYN, so the sequence numbers * are correct but new passive connections we have no * information about RTTmin at this time so we simply set it to * TCP_WESTWOOD_INIT_RTT. This value was chosen to be too conservative * since in this way we're sure it will be updated in a consistent * way as soon as possible. It will reasonably happen within the first * RTT period of the connection lifetime. */ static void tcp_westwood_init(struct sock *sk) { struct westwood *w = inet_csk_ca(sk); w->bk = 0; w->bw_ns_est = 0; w->bw_est = 0; w->accounted = 0; w->cumul_ack = 0; w->reset_rtt_min = 1; w->rtt_min = w->rtt = TCP_WESTWOOD_INIT_RTT; w->rtt_win_sx = tcp_jiffies32; w->snd_una = tcp_sk(sk)->snd_una; w->first_ack = 1; } /* * @westwood_do_filter * Low-pass filter. Implemented using constant coefficients. */ static inline u32 westwood_do_filter(u32 a, u32 b) { return ((7 * a) + b) >> 3; } static void westwood_filter(struct westwood *w, u32 delta) { /* If the filter is empty fill it with the first sample of bandwidth */ if (w->bw_ns_est == 0 && w->bw_est == 0) { w->bw_ns_est = w->bk / delta; w->bw_est = w->bw_ns_est; } else { w->bw_ns_est = westwood_do_filter(w->bw_ns_est, w->bk / delta); w->bw_est = westwood_do_filter(w->bw_est, w->bw_ns_est); } } /* * @westwood_pkts_acked * Called after processing group of packets. * but all westwood needs is the last sample of srtt. */ static void tcp_westwood_pkts_acked(struct sock *sk, const struct ack_sample *sample) { struct westwood *w = inet_csk_ca(sk); if (sample->rtt_us > 0) w->rtt = usecs_to_jiffies(sample->rtt_us); } /* * @westwood_update_window * It updates RTT evaluation window if it is the right moment to do * it. If so it calls filter for evaluating bandwidth. */ static void westwood_update_window(struct sock *sk) { struct westwood *w = inet_csk_ca(sk); s32 delta = tcp_jiffies32 - w->rtt_win_sx; /* Initialize w->snd_una with the first acked sequence number in order * to fix mismatch between tp->snd_una and w->snd_una for the first * bandwidth sample */ if (w->first_ack) { w->snd_una = tcp_sk(sk)->snd_una; w->first_ack = 0; } /* * See if a RTT-window has passed. * Be careful since if RTT is less than * 50ms we don't filter but we continue 'building the sample'. * This minimum limit was chosen since an estimation on small * time intervals is better to avoid... * Obviously on a LAN we reasonably will always have * right_bound = left_bound + WESTWOOD_RTT_MIN */ if (w->rtt && delta > max_t(u32, w->rtt, TCP_WESTWOOD_RTT_MIN)) { westwood_filter(w, delta); w->bk = 0; w->rtt_win_sx = tcp_jiffies32; } } static inline void update_rtt_min(struct westwood *w) { if (w->reset_rtt_min) { w->rtt_min = w->rtt; w->reset_rtt_min = 0; } else w->rtt_min = min(w->rtt, w->rtt_min); } /* * @westwood_fast_bw * It is called when we are in fast path. In particular it is called when * header prediction is successful. In such case in fact update is * straight forward and doesn't need any particular care. */ static inline void westwood_fast_bw(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct westwood *w = inet_csk_ca(sk); westwood_update_window(sk); w->bk += tp->snd_una - w->snd_una; w->snd_una = tp->snd_una; update_rtt_min(w); } /* * @westwood_acked_count * This function evaluates cumul_ack for evaluating bk in case of * delayed or partial acks. */ static inline u32 westwood_acked_count(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct westwood *w = inet_csk_ca(sk); w->cumul_ack = tp->snd_una - w->snd_una; /* If cumul_ack is 0 this is a dupack since it's not moving * tp->snd_una. */ if (!w->cumul_ack) { w->accounted += tp->mss_cache; w->cumul_ack = tp->mss_cache; } if (w->cumul_ack > tp->mss_cache) { /* Partial or delayed ack */ if (w->accounted >= w->cumul_ack) { w->accounted -= w->cumul_ack; w->cumul_ack = tp->mss_cache; } else { w->cumul_ack -= w->accounted; w->accounted = 0; } } w->snd_una = tp->snd_una; return w->cumul_ack; } /* * TCP Westwood * Here limit is evaluated as Bw estimation*RTTmin (for obtaining it * in packets we use mss_cache). Rttmin is guaranteed to be >= 2 * so avoids ever returning 0. */ static u32 tcp_westwood_bw_rttmin(const struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); const struct westwood *w = inet_csk_ca(sk); return max_t(u32, (w->bw_est * w->rtt_min) / tp->mss_cache, 2); } static void tcp_westwood_ack(struct sock *sk, u32 ack_flags) { if (ack_flags & CA_ACK_SLOWPATH) { struct westwood *w = inet_csk_ca(sk); westwood_update_window(sk); w->bk += westwood_acked_count(sk); update_rtt_min(w); return; } westwood_fast_bw(sk); } static void tcp_westwood_event(struct sock *sk, enum tcp_ca_event event) { struct tcp_sock *tp = tcp_sk(sk); struct westwood *w = inet_csk_ca(sk); switch (event) { case CA_EVENT_COMPLETE_CWR: tp->snd_ssthresh = tcp_westwood_bw_rttmin(sk); tcp_snd_cwnd_set(tp, tp->snd_ssthresh); break; case CA_EVENT_LOSS: tp->snd_ssthresh = tcp_westwood_bw_rttmin(sk); /* Update RTT_min when next ack arrives */ w->reset_rtt_min = 1; break; default: /* don't care */ break; } } /* Extract info for Tcp socket info provided via netlink. */ static size_t tcp_westwood_info(struct sock *sk, u32 ext, int *attr, union tcp_cc_info *info) { const struct westwood *ca = inet_csk_ca(sk); if (ext & (1 << (INET_DIAG_VEGASINFO - 1))) { info->vegas.tcpv_enabled = 1; info->vegas.tcpv_rttcnt = 0; info->vegas.tcpv_rtt = jiffies_to_usecs(ca->rtt); info->vegas.tcpv_minrtt = jiffies_to_usecs(ca->rtt_min); *attr = INET_DIAG_VEGASINFO; return sizeof(struct tcpvegas_info); } return 0; } static struct tcp_congestion_ops tcp_westwood __read_mostly = { .init = tcp_westwood_init, .ssthresh = tcp_reno_ssthresh, .cong_avoid = tcp_reno_cong_avoid, .undo_cwnd = tcp_reno_undo_cwnd, .cwnd_event = tcp_westwood_event, .in_ack_event = tcp_westwood_ack, .get_info = tcp_westwood_info, .pkts_acked = tcp_westwood_pkts_acked, .owner = THIS_MODULE, .name = "westwood" }; static int __init tcp_westwood_register(void) { BUILD_BUG_ON(sizeof(struct westwood) > ICSK_CA_PRIV_SIZE); return tcp_register_congestion_control(&tcp_westwood); } static void __exit tcp_westwood_unregister(void) { tcp_unregister_congestion_control(&tcp_westwood); } module_init(tcp_westwood_register); module_exit(tcp_westwood_unregister); MODULE_AUTHOR("Stephen Hemminger, Angelo Dell'Aera"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("TCP Westwood+");
linux-master
net/ipv4/tcp_westwood.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * INET protocol dispatch tables. * * Authors: Ross Biro * Fred N. van Kempen, <[email protected]> * * Fixes: * Alan Cox : Ahah! udp icmp errors don't work because * udp_err is never called! * Alan Cox : Added new fields for init and ready for * proper fragmentation (_NO_ 4K limits!) * Richard Colella : Hang on hash collision * Vince Laviano : Modified inet_del_protocol() to correctly * maintain copy bit. */ #include <linux/cache.h> #include <linux/module.h> #include <linux/netdevice.h> #include <linux/spinlock.h> #include <net/protocol.h> struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS] __read_mostly; EXPORT_SYMBOL(inet_protos); const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS] __read_mostly; EXPORT_SYMBOL(inet_offloads); int inet_add_protocol(const struct net_protocol *prot, unsigned char protocol) { return !cmpxchg((const struct net_protocol **)&inet_protos[protocol], NULL, prot) ? 0 : -1; } EXPORT_SYMBOL(inet_add_protocol); int inet_add_offload(const struct net_offload *prot, unsigned char protocol) { return !cmpxchg((const struct net_offload **)&inet_offloads[protocol], NULL, prot) ? 0 : -1; } EXPORT_SYMBOL(inet_add_offload); int inet_del_protocol(const struct net_protocol *prot, unsigned char protocol) { int ret; ret = (cmpxchg((const struct net_protocol **)&inet_protos[protocol], prot, NULL) == prot) ? 0 : -1; synchronize_net(); return ret; } EXPORT_SYMBOL(inet_del_protocol); int inet_del_offload(const struct net_offload *prot, unsigned char protocol) { int ret; ret = (cmpxchg((const struct net_offload **)&inet_offloads[protocol], prot, NULL) == prot) ? 0 : -1; synchronize_net(); return ret; } EXPORT_SYMBOL(inet_del_offload);
linux-master
net/ipv4/protocol.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * IPv4 Forwarding Information Base: policy rules. * * Authors: Alexey Kuznetsov, <[email protected]> * Thomas Graf <[email protected]> * * Fixes: * Rani Assaf : local_rule cannot be deleted * Marc Boucher : routing by fwmark */ #include <linux/types.h> #include <linux/kernel.h> #include <linux/netdevice.h> #include <linux/netlink.h> #include <linux/inetdevice.h> #include <linux/init.h> #include <linux/list.h> #include <linux/rcupdate.h> #include <linux/export.h> #include <net/inet_dscp.h> #include <net/ip.h> #include <net/route.h> #include <net/tcp.h> #include <net/ip_fib.h> #include <net/nexthop.h> #include <net/fib_rules.h> #include <linux/indirect_call_wrapper.h> struct fib4_rule { struct fib_rule common; u8 dst_len; u8 src_len; dscp_t dscp; __be32 src; __be32 srcmask; __be32 dst; __be32 dstmask; #ifdef CONFIG_IP_ROUTE_CLASSID u32 tclassid; #endif }; static bool fib4_rule_matchall(const struct fib_rule *rule) { struct fib4_rule *r = container_of(rule, struct fib4_rule, common); if (r->dst_len || r->src_len || r->dscp) return false; return fib_rule_matchall(rule); } bool fib4_rule_default(const struct fib_rule *rule) { if (!fib4_rule_matchall(rule) || rule->action != FR_ACT_TO_TBL || rule->l3mdev) return false; if (rule->table != RT_TABLE_LOCAL && rule->table != RT_TABLE_MAIN && rule->table != RT_TABLE_DEFAULT) return false; return true; } EXPORT_SYMBOL_GPL(fib4_rule_default); int fib4_rules_dump(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { return fib_rules_dump(net, nb, AF_INET, extack); } unsigned int fib4_rules_seq_read(struct net *net) { return fib_rules_seq_read(net, AF_INET); } int __fib_lookup(struct net *net, struct flowi4 *flp, struct fib_result *res, unsigned int flags) { struct fib_lookup_arg arg = { .result = res, .flags = flags, }; int err; /* update flow if oif or iif point to device enslaved to l3mdev */ l3mdev_update_flow(net, flowi4_to_flowi(flp)); err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg); #ifdef CONFIG_IP_ROUTE_CLASSID if (arg.rule) res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid; else res->tclassid = 0; #endif if (err == -ESRCH) err = -ENETUNREACH; return err; } EXPORT_SYMBOL_GPL(__fib_lookup); INDIRECT_CALLABLE_SCOPE int fib4_rule_action(struct fib_rule *rule, struct flowi *flp, int flags, struct fib_lookup_arg *arg) { int err = -EAGAIN; struct fib_table *tbl; u32 tb_id; switch (rule->action) { case FR_ACT_TO_TBL: break; case FR_ACT_UNREACHABLE: return -ENETUNREACH; case FR_ACT_PROHIBIT: return -EACCES; case FR_ACT_BLACKHOLE: default: return -EINVAL; } rcu_read_lock(); tb_id = fib_rule_get_table(rule, arg); tbl = fib_get_table(rule->fr_net, tb_id); if (tbl) err = fib_table_lookup(tbl, &flp->u.ip4, (struct fib_result *)arg->result, arg->flags); rcu_read_unlock(); return err; } INDIRECT_CALLABLE_SCOPE bool fib4_rule_suppress(struct fib_rule *rule, int flags, struct fib_lookup_arg *arg) { struct fib_result *result = arg->result; struct net_device *dev = NULL; if (result->fi) { struct fib_nh_common *nhc = fib_info_nhc(result->fi, 0); dev = nhc->nhc_dev; } /* do not accept result if the route does * not meet the required prefix length */ if (result->prefixlen <= rule->suppress_prefixlen) goto suppress_route; /* do not accept result if the route uses a device * belonging to a forbidden interface group */ if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup) goto suppress_route; return false; suppress_route: if (!(arg->flags & FIB_LOOKUP_NOREF)) fib_info_put(result->fi); return true; } INDIRECT_CALLABLE_SCOPE int fib4_rule_match(struct fib_rule *rule, struct flowi *fl, int flags) { struct fib4_rule *r = (struct fib4_rule *) rule; struct flowi4 *fl4 = &fl->u.ip4; __be32 daddr = fl4->daddr; __be32 saddr = fl4->saddr; if (((saddr ^ r->src) & r->srcmask) || ((daddr ^ r->dst) & r->dstmask)) return 0; if (r->dscp && r->dscp != inet_dsfield_to_dscp(fl4->flowi4_tos)) return 0; if (rule->ip_proto && (rule->ip_proto != fl4->flowi4_proto)) return 0; if (fib_rule_port_range_set(&rule->sport_range) && !fib_rule_port_inrange(&rule->sport_range, fl4->fl4_sport)) return 0; if (fib_rule_port_range_set(&rule->dport_range) && !fib_rule_port_inrange(&rule->dport_range, fl4->fl4_dport)) return 0; return 1; } static struct fib_table *fib_empty_table(struct net *net) { u32 id = 1; while (1) { if (!fib_get_table(net, id)) return fib_new_table(net, id); if (id++ == RT_TABLE_MAX) break; } return NULL; } static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb, struct fib_rule_hdr *frh, struct nlattr **tb, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); int err = -EINVAL; struct fib4_rule *rule4 = (struct fib4_rule *) rule; if (!inet_validate_dscp(frh->tos)) { NL_SET_ERR_MSG(extack, "Invalid dsfield (tos): ECN bits must be 0"); goto errout; } /* IPv4 currently doesn't handle high order DSCP bits correctly */ if (frh->tos & ~IPTOS_TOS_MASK) { NL_SET_ERR_MSG(extack, "Invalid tos"); goto errout; } rule4->dscp = inet_dsfield_to_dscp(frh->tos); /* split local/main if they are not already split */ err = fib_unmerge(net); if (err) goto errout; if (rule->table == RT_TABLE_UNSPEC && !rule->l3mdev) { if (rule->action == FR_ACT_TO_TBL) { struct fib_table *table; table = fib_empty_table(net); if (!table) { err = -ENOBUFS; goto errout; } rule->table = table->tb_id; } } if (frh->src_len) rule4->src = nla_get_in_addr(tb[FRA_SRC]); if (frh->dst_len) rule4->dst = nla_get_in_addr(tb[FRA_DST]); #ifdef CONFIG_IP_ROUTE_CLASSID if (tb[FRA_FLOW]) { rule4->tclassid = nla_get_u32(tb[FRA_FLOW]); if (rule4->tclassid) atomic_inc(&net->ipv4.fib_num_tclassid_users); } #endif if (fib_rule_requires_fldissect(rule)) net->ipv4.fib_rules_require_fldissect++; rule4->src_len = frh->src_len; rule4->srcmask = inet_make_mask(rule4->src_len); rule4->dst_len = frh->dst_len; rule4->dstmask = inet_make_mask(rule4->dst_len); net->ipv4.fib_has_custom_rules = true; err = 0; errout: return err; } static int fib4_rule_delete(struct fib_rule *rule) { struct net *net = rule->fr_net; int err; /* split local/main if they are not already split */ err = fib_unmerge(net); if (err) goto errout; #ifdef CONFIG_IP_ROUTE_CLASSID if (((struct fib4_rule *)rule)->tclassid) atomic_dec(&net->ipv4.fib_num_tclassid_users); #endif net->ipv4.fib_has_custom_rules = true; if (net->ipv4.fib_rules_require_fldissect && fib_rule_requires_fldissect(rule)) net->ipv4.fib_rules_require_fldissect--; errout: return err; } static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, struct nlattr **tb) { struct fib4_rule *rule4 = (struct fib4_rule *) rule; if (frh->src_len && (rule4->src_len != frh->src_len)) return 0; if (frh->dst_len && (rule4->dst_len != frh->dst_len)) return 0; if (frh->tos && inet_dscp_to_dsfield(rule4->dscp) != frh->tos) return 0; #ifdef CONFIG_IP_ROUTE_CLASSID if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW]))) return 0; #endif if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC]))) return 0; if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST]))) return 0; return 1; } static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb, struct fib_rule_hdr *frh) { struct fib4_rule *rule4 = (struct fib4_rule *) rule; frh->dst_len = rule4->dst_len; frh->src_len = rule4->src_len; frh->tos = inet_dscp_to_dsfield(rule4->dscp); if ((rule4->dst_len && nla_put_in_addr(skb, FRA_DST, rule4->dst)) || (rule4->src_len && nla_put_in_addr(skb, FRA_SRC, rule4->src))) goto nla_put_failure; #ifdef CONFIG_IP_ROUTE_CLASSID if (rule4->tclassid && nla_put_u32(skb, FRA_FLOW, rule4->tclassid)) goto nla_put_failure; #endif return 0; nla_put_failure: return -ENOBUFS; } static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule) { return nla_total_size(4) /* dst */ + nla_total_size(4) /* src */ + nla_total_size(4); /* flow */ } static void fib4_rule_flush_cache(struct fib_rules_ops *ops) { rt_cache_flush(ops->fro_net); } static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = { .family = AF_INET, .rule_size = sizeof(struct fib4_rule), .addr_size = sizeof(u32), .action = fib4_rule_action, .suppress = fib4_rule_suppress, .match = fib4_rule_match, .configure = fib4_rule_configure, .delete = fib4_rule_delete, .compare = fib4_rule_compare, .fill = fib4_rule_fill, .nlmsg_payload = fib4_rule_nlmsg_payload, .flush_cache = fib4_rule_flush_cache, .nlgroup = RTNLGRP_IPV4_RULE, .owner = THIS_MODULE, }; static int fib_default_rules_init(struct fib_rules_ops *ops) { int err; err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0); if (err < 0) return err; err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0); if (err < 0) return err; err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0); if (err < 0) return err; return 0; } int __net_init fib4_rules_init(struct net *net) { int err; struct fib_rules_ops *ops; ops = fib_rules_register(&fib4_rules_ops_template, net); if (IS_ERR(ops)) return PTR_ERR(ops); err = fib_default_rules_init(ops); if (err < 0) goto fail; net->ipv4.rules_ops = ops; net->ipv4.fib_has_custom_rules = false; net->ipv4.fib_rules_require_fldissect = 0; return 0; fail: /* also cleans all rules already added */ fib_rules_unregister(ops); return err; } void __net_exit fib4_rules_exit(struct net *net) { fib_rules_unregister(net->ipv4.rules_ops); }
linux-master
net/ipv4/fib_rules.c
/* * IPv4 specific functions of netfilter core * * Rusty Russell (C) 2000 -- This code is GPL. * Patrick McHardy (C) 2006-2012 */ #include <linux/kernel.h> #include <linux/netfilter.h> #include <linux/netfilter_ipv4.h> #include <linux/ip.h> #include <linux/skbuff.h> #include <linux/gfp.h> #include <linux/export.h> #include <net/route.h> #include <net/xfrm.h> #include <net/ip.h> #include <net/netfilter/nf_queue.h> /* route_me_harder function, used by iptable_nat, iptable_mangle + ip_queue */ int ip_route_me_harder(struct net *net, struct sock *sk, struct sk_buff *skb, unsigned int addr_type) { const struct iphdr *iph = ip_hdr(skb); struct rtable *rt; struct flowi4 fl4 = {}; __be32 saddr = iph->saddr; __u8 flags; struct net_device *dev = skb_dst(skb)->dev; struct flow_keys flkeys; unsigned int hh_len; sk = sk_to_full_sk(sk); flags = sk ? inet_sk_flowi_flags(sk) : 0; if (addr_type == RTN_UNSPEC) addr_type = inet_addr_type_dev_table(net, dev, saddr); if (addr_type == RTN_LOCAL || addr_type == RTN_UNICAST) flags |= FLOWI_FLAG_ANYSRC; else saddr = 0; /* some non-standard hacks like ipt_REJECT.c:send_reset() can cause * packets with foreign saddr to appear on the NF_INET_LOCAL_OUT hook. */ fl4.daddr = iph->daddr; fl4.saddr = saddr; fl4.flowi4_tos = RT_TOS(iph->tos); fl4.flowi4_oif = sk ? sk->sk_bound_dev_if : 0; fl4.flowi4_l3mdev = l3mdev_master_ifindex(dev); fl4.flowi4_mark = skb->mark; fl4.flowi4_flags = flags; fib4_rules_early_flow_dissect(net, skb, &fl4, &flkeys); rt = ip_route_output_key(net, &fl4); if (IS_ERR(rt)) return PTR_ERR(rt); /* Drop old route. */ skb_dst_drop(skb); skb_dst_set(skb, &rt->dst); if (skb_dst(skb)->error) return skb_dst(skb)->error; #ifdef CONFIG_XFRM if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) && xfrm_decode_session(skb, flowi4_to_flowi(&fl4), AF_INET) == 0) { struct dst_entry *dst = skb_dst(skb); skb_dst_set(skb, NULL); dst = xfrm_lookup(net, dst, flowi4_to_flowi(&fl4), sk, 0); if (IS_ERR(dst)) return PTR_ERR(dst); skb_dst_set(skb, dst); } #endif /* Change in oif may mean change in hh_len. */ hh_len = skb_dst(skb)->dev->hard_header_len; if (skb_headroom(skb) < hh_len && pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)), 0, GFP_ATOMIC)) return -ENOMEM; return 0; } EXPORT_SYMBOL(ip_route_me_harder); int nf_ip_route(struct net *net, struct dst_entry **dst, struct flowi *fl, bool strict __always_unused) { struct rtable *rt = ip_route_output_key(net, &fl->u.ip4); if (IS_ERR(rt)) return PTR_ERR(rt); *dst = &rt->dst; return 0; } EXPORT_SYMBOL_GPL(nf_ip_route);
linux-master
net/ipv4/netfilter.c
// SPDX-License-Identifier: GPL-2.0-only /* * TCP NV: TCP with Congestion Avoidance * * TCP-NV is a successor of TCP-Vegas that has been developed to * deal with the issues that occur in modern networks. * Like TCP-Vegas, TCP-NV supports true congestion avoidance, * the ability to detect congestion before packet losses occur. * When congestion (queue buildup) starts to occur, TCP-NV * predicts what the cwnd size should be for the current * throughput and it reduces the cwnd proportionally to * the difference between the current cwnd and the predicted cwnd. * * NV is only recommeneded for traffic within a data center, and when * all the flows are NV (at least those within the data center). This * is due to the inherent unfairness between flows using losses to * detect congestion (congestion control) and those that use queue * buildup to detect congestion (congestion avoidance). * * Note: High NIC coalescence values may lower the performance of NV * due to the increased noise in RTT values. In particular, we have * seen issues with rx-frames values greater than 8. * * TODO: * 1) Add mechanism to deal with reverse congestion. */ #include <linux/module.h> #include <linux/math64.h> #include <net/tcp.h> #include <linux/inet_diag.h> /* TCP NV parameters * * nv_pad Max number of queued packets allowed in network * nv_pad_buffer Do not grow cwnd if this closed to nv_pad * nv_reset_period How often (in) seconds)to reset min_rtt * nv_min_cwnd Don't decrease cwnd below this if there are no losses * nv_cong_dec_mult Decrease cwnd by X% (30%) of congestion when detected * nv_ssthresh_factor On congestion set ssthresh to this * <desired cwnd> / 8 * nv_rtt_factor RTT averaging factor * nv_loss_dec_factor Decrease cwnd to this (80%) when losses occur * nv_dec_eval_min_calls Wait this many RTT measurements before dec cwnd * nv_inc_eval_min_calls Wait this many RTT measurements before inc cwnd * nv_ssthresh_eval_min_calls Wait this many RTT measurements before stopping * slow-start due to congestion * nv_stop_rtt_cnt Only grow cwnd for this many RTTs after non-congestion * nv_rtt_min_cnt Wait these many RTTs before making congesion decision * nv_cwnd_growth_rate_neg * nv_cwnd_growth_rate_pos * How quickly to double growth rate (not rate) of cwnd when not * congested. One value (nv_cwnd_growth_rate_neg) for when * rate < 1 pkt/RTT (after losses). The other (nv_cwnd_growth_rate_pos) * otherwise. */ static int nv_pad __read_mostly = 10; static int nv_pad_buffer __read_mostly = 2; static int nv_reset_period __read_mostly = 5; /* in seconds */ static int nv_min_cwnd __read_mostly = 2; static int nv_cong_dec_mult __read_mostly = 30 * 128 / 100; /* = 30% */ static int nv_ssthresh_factor __read_mostly = 8; /* = 1 */ static int nv_rtt_factor __read_mostly = 128; /* = 1/2*old + 1/2*new */ static int nv_loss_dec_factor __read_mostly = 819; /* => 80% */ static int nv_cwnd_growth_rate_neg __read_mostly = 8; static int nv_cwnd_growth_rate_pos __read_mostly; /* 0 => fixed like Reno */ static int nv_dec_eval_min_calls __read_mostly = 60; static int nv_inc_eval_min_calls __read_mostly = 20; static int nv_ssthresh_eval_min_calls __read_mostly = 30; static int nv_stop_rtt_cnt __read_mostly = 10; static int nv_rtt_min_cnt __read_mostly = 2; module_param(nv_pad, int, 0644); MODULE_PARM_DESC(nv_pad, "max queued packets allowed in network"); module_param(nv_reset_period, int, 0644); MODULE_PARM_DESC(nv_reset_period, "nv_min_rtt reset period (secs)"); module_param(nv_min_cwnd, int, 0644); MODULE_PARM_DESC(nv_min_cwnd, "NV will not decrease cwnd below this value" " without losses"); /* TCP NV Parameters */ struct tcpnv { unsigned long nv_min_rtt_reset_jiffies; /* when to switch to * nv_min_rtt_new */ s8 cwnd_growth_factor; /* Current cwnd growth factor, * < 0 => less than 1 packet/RTT */ u8 available8; u16 available16; u8 nv_allow_cwnd_growth:1, /* whether cwnd can grow */ nv_reset:1, /* whether to reset values */ nv_catchup:1; /* whether we are growing because * of temporary cwnd decrease */ u8 nv_eval_call_cnt; /* call count since last eval */ u8 nv_min_cwnd; /* nv won't make a ca decision if cwnd is * smaller than this. It may grow to handle * TSO, LRO and interrupt coalescence because * with these a small cwnd cannot saturate * the link. Note that this is different from * the file local nv_min_cwnd */ u8 nv_rtt_cnt; /* RTTs without making ca decision */; u32 nv_last_rtt; /* last rtt */ u32 nv_min_rtt; /* active min rtt. Used to determine slope */ u32 nv_min_rtt_new; /* min rtt for future use */ u32 nv_base_rtt; /* If non-zero it represents the threshold for * congestion */ u32 nv_lower_bound_rtt; /* Used in conjunction with nv_base_rtt. It is * set to 80% of nv_base_rtt. It helps reduce * unfairness between flows */ u32 nv_rtt_max_rate; /* max rate seen during current RTT */ u32 nv_rtt_start_seq; /* current RTT ends when packet arrives * acking beyond nv_rtt_start_seq */ u32 nv_last_snd_una; /* Previous value of tp->snd_una. It is * used to determine bytes acked since last * call to bictcp_acked */ u32 nv_no_cong_cnt; /* Consecutive no congestion decisions */ }; #define NV_INIT_RTT U32_MAX #define NV_MIN_CWND 4 #define NV_MIN_CWND_GROW 2 #define NV_TSO_CWND_BOUND 80 static inline void tcpnv_reset(struct tcpnv *ca, struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); ca->nv_reset = 0; ca->nv_no_cong_cnt = 0; ca->nv_rtt_cnt = 0; ca->nv_last_rtt = 0; ca->nv_rtt_max_rate = 0; ca->nv_rtt_start_seq = tp->snd_una; ca->nv_eval_call_cnt = 0; ca->nv_last_snd_una = tp->snd_una; } static void tcpnv_init(struct sock *sk) { struct tcpnv *ca = inet_csk_ca(sk); int base_rtt; tcpnv_reset(ca, sk); /* See if base_rtt is available from socket_ops bpf program. * It is meant to be used in environments, such as communication * within a datacenter, where we have reasonable estimates of * RTTs */ base_rtt = tcp_call_bpf(sk, BPF_SOCK_OPS_BASE_RTT, 0, NULL); if (base_rtt > 0) { ca->nv_base_rtt = base_rtt; ca->nv_lower_bound_rtt = (base_rtt * 205) >> 8; /* 80% */ } else { ca->nv_base_rtt = 0; ca->nv_lower_bound_rtt = 0; } ca->nv_allow_cwnd_growth = 1; ca->nv_min_rtt_reset_jiffies = jiffies + 2 * HZ; ca->nv_min_rtt = NV_INIT_RTT; ca->nv_min_rtt_new = NV_INIT_RTT; ca->nv_min_cwnd = NV_MIN_CWND; ca->nv_catchup = 0; ca->cwnd_growth_factor = 0; } /* If provided, apply upper (base_rtt) and lower (lower_bound_rtt) * bounds to RTT. */ inline u32 nv_get_bounded_rtt(struct tcpnv *ca, u32 val) { if (ca->nv_lower_bound_rtt > 0 && val < ca->nv_lower_bound_rtt) return ca->nv_lower_bound_rtt; else if (ca->nv_base_rtt > 0 && val > ca->nv_base_rtt) return ca->nv_base_rtt; else return val; } static void tcpnv_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct tcpnv *ca = inet_csk_ca(sk); u32 cnt; if (!tcp_is_cwnd_limited(sk)) return; /* Only grow cwnd if NV has not detected congestion */ if (!ca->nv_allow_cwnd_growth) return; if (tcp_in_slow_start(tp)) { acked = tcp_slow_start(tp, acked); if (!acked) return; } if (ca->cwnd_growth_factor < 0) { cnt = tcp_snd_cwnd(tp) << -ca->cwnd_growth_factor; tcp_cong_avoid_ai(tp, cnt, acked); } else { cnt = max(4U, tcp_snd_cwnd(tp) >> ca->cwnd_growth_factor); tcp_cong_avoid_ai(tp, cnt, acked); } } static u32 tcpnv_recalc_ssthresh(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); return max((tcp_snd_cwnd(tp) * nv_loss_dec_factor) >> 10, 2U); } static void tcpnv_state(struct sock *sk, u8 new_state) { struct tcpnv *ca = inet_csk_ca(sk); if (new_state == TCP_CA_Open && ca->nv_reset) { tcpnv_reset(ca, sk); } else if (new_state == TCP_CA_Loss || new_state == TCP_CA_CWR || new_state == TCP_CA_Recovery) { ca->nv_reset = 1; ca->nv_allow_cwnd_growth = 0; if (new_state == TCP_CA_Loss) { /* Reset cwnd growth factor to Reno value */ if (ca->cwnd_growth_factor > 0) ca->cwnd_growth_factor = 0; /* Decrease growth rate if allowed */ if (nv_cwnd_growth_rate_neg > 0 && ca->cwnd_growth_factor > -8) ca->cwnd_growth_factor--; } } } /* Do congestion avoidance calculations for TCP-NV */ static void tcpnv_acked(struct sock *sk, const struct ack_sample *sample) { const struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct tcpnv *ca = inet_csk_ca(sk); unsigned long now = jiffies; u64 rate64; u32 rate, max_win, cwnd_by_slope; u32 avg_rtt; u32 bytes_acked = 0; /* Some calls are for duplicates without timetamps */ if (sample->rtt_us < 0) return; /* If not in TCP_CA_Open or TCP_CA_Disorder states, skip. */ if (icsk->icsk_ca_state != TCP_CA_Open && icsk->icsk_ca_state != TCP_CA_Disorder) return; /* Stop cwnd growth if we were in catch up mode */ if (ca->nv_catchup && tcp_snd_cwnd(tp) >= nv_min_cwnd) { ca->nv_catchup = 0; ca->nv_allow_cwnd_growth = 0; } bytes_acked = tp->snd_una - ca->nv_last_snd_una; ca->nv_last_snd_una = tp->snd_una; if (sample->in_flight == 0) return; /* Calculate moving average of RTT */ if (nv_rtt_factor > 0) { if (ca->nv_last_rtt > 0) { avg_rtt = (((u64)sample->rtt_us) * nv_rtt_factor + ((u64)ca->nv_last_rtt) * (256 - nv_rtt_factor)) >> 8; } else { avg_rtt = sample->rtt_us; ca->nv_min_rtt = avg_rtt << 1; } ca->nv_last_rtt = avg_rtt; } else { avg_rtt = sample->rtt_us; } /* rate in 100's bits per second */ rate64 = ((u64)sample->in_flight) * 80000; do_div(rate64, avg_rtt ?: 1); rate = (u32)rate64; /* Remember the maximum rate seen during this RTT * Note: It may be more than one RTT. This function should be * called at least nv_dec_eval_min_calls times. */ if (ca->nv_rtt_max_rate < rate) ca->nv_rtt_max_rate = rate; /* We have valid information, increment counter */ if (ca->nv_eval_call_cnt < 255) ca->nv_eval_call_cnt++; /* Apply bounds to rtt. Only used to update min_rtt */ avg_rtt = nv_get_bounded_rtt(ca, avg_rtt); /* update min rtt if necessary */ if (avg_rtt < ca->nv_min_rtt) ca->nv_min_rtt = avg_rtt; /* update future min_rtt if necessary */ if (avg_rtt < ca->nv_min_rtt_new) ca->nv_min_rtt_new = avg_rtt; /* nv_min_rtt is updated with the minimum (possibley averaged) rtt * seen in the last sysctl_tcp_nv_reset_period seconds (i.e. a * warm reset). This new nv_min_rtt will be continued to be updated * and be used for another sysctl_tcp_nv_reset_period seconds, * when it will be updated again. * In practice we introduce some randomness, so the actual period used * is chosen randomly from the range: * [sysctl_tcp_nv_reset_period*3/4, sysctl_tcp_nv_reset_period*5/4) */ if (time_after_eq(now, ca->nv_min_rtt_reset_jiffies)) { unsigned char rand; ca->nv_min_rtt = ca->nv_min_rtt_new; ca->nv_min_rtt_new = NV_INIT_RTT; get_random_bytes(&rand, 1); ca->nv_min_rtt_reset_jiffies = now + ((nv_reset_period * (384 + rand) * HZ) >> 9); /* Every so often we decrease ca->nv_min_cwnd in case previous * value is no longer accurate. */ ca->nv_min_cwnd = max(ca->nv_min_cwnd / 2, NV_MIN_CWND); } /* Once per RTT check if we need to do congestion avoidance */ if (before(ca->nv_rtt_start_seq, tp->snd_una)) { ca->nv_rtt_start_seq = tp->snd_nxt; if (ca->nv_rtt_cnt < 0xff) /* Increase counter for RTTs without CA decision */ ca->nv_rtt_cnt++; /* If this function is only called once within an RTT * the cwnd is probably too small (in some cases due to * tso, lro or interrupt coalescence), so we increase * ca->nv_min_cwnd. */ if (ca->nv_eval_call_cnt == 1 && bytes_acked >= (ca->nv_min_cwnd - 1) * tp->mss_cache && ca->nv_min_cwnd < (NV_TSO_CWND_BOUND + 1)) { ca->nv_min_cwnd = min(ca->nv_min_cwnd + NV_MIN_CWND_GROW, NV_TSO_CWND_BOUND + 1); ca->nv_rtt_start_seq = tp->snd_nxt + ca->nv_min_cwnd * tp->mss_cache; ca->nv_eval_call_cnt = 0; ca->nv_allow_cwnd_growth = 1; return; } /* Find the ideal cwnd for current rate from slope * slope = 80000.0 * mss / nv_min_rtt * cwnd_by_slope = nv_rtt_max_rate / slope */ cwnd_by_slope = (u32) div64_u64(((u64)ca->nv_rtt_max_rate) * ca->nv_min_rtt, 80000ULL * tp->mss_cache); max_win = cwnd_by_slope + nv_pad; /* If cwnd > max_win, decrease cwnd * if cwnd < max_win, grow cwnd * else leave the same */ if (tcp_snd_cwnd(tp) > max_win) { /* there is congestion, check that it is ok * to make a CA decision * 1. We should have at least nv_dec_eval_min_calls * data points before making a CA decision * 2. We only make a congesion decision after * nv_rtt_min_cnt RTTs */ if (ca->nv_rtt_cnt < nv_rtt_min_cnt) { return; } else if (tp->snd_ssthresh == TCP_INFINITE_SSTHRESH) { if (ca->nv_eval_call_cnt < nv_ssthresh_eval_min_calls) return; /* otherwise we will decrease cwnd */ } else if (ca->nv_eval_call_cnt < nv_dec_eval_min_calls) { if (ca->nv_allow_cwnd_growth && ca->nv_rtt_cnt > nv_stop_rtt_cnt) ca->nv_allow_cwnd_growth = 0; return; } /* We have enough data to determine we are congested */ ca->nv_allow_cwnd_growth = 0; tp->snd_ssthresh = (nv_ssthresh_factor * max_win) >> 3; if (tcp_snd_cwnd(tp) - max_win > 2) { /* gap > 2, we do exponential cwnd decrease */ int dec; dec = max(2U, ((tcp_snd_cwnd(tp) - max_win) * nv_cong_dec_mult) >> 7); tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) - dec); } else if (nv_cong_dec_mult > 0) { tcp_snd_cwnd_set(tp, max_win); } if (ca->cwnd_growth_factor > 0) ca->cwnd_growth_factor = 0; ca->nv_no_cong_cnt = 0; } else if (tcp_snd_cwnd(tp) <= max_win - nv_pad_buffer) { /* There is no congestion, grow cwnd if allowed*/ if (ca->nv_eval_call_cnt < nv_inc_eval_min_calls) return; ca->nv_allow_cwnd_growth = 1; ca->nv_no_cong_cnt++; if (ca->cwnd_growth_factor < 0 && nv_cwnd_growth_rate_neg > 0 && ca->nv_no_cong_cnt > nv_cwnd_growth_rate_neg) { ca->cwnd_growth_factor++; ca->nv_no_cong_cnt = 0; } else if (ca->cwnd_growth_factor >= 0 && nv_cwnd_growth_rate_pos > 0 && ca->nv_no_cong_cnt > nv_cwnd_growth_rate_pos) { ca->cwnd_growth_factor++; ca->nv_no_cong_cnt = 0; } } else { /* cwnd is in-between, so do nothing */ return; } /* update state */ ca->nv_eval_call_cnt = 0; ca->nv_rtt_cnt = 0; ca->nv_rtt_max_rate = 0; /* Don't want to make cwnd < nv_min_cwnd * (it wasn't before, if it is now is because nv * decreased it). */ if (tcp_snd_cwnd(tp) < nv_min_cwnd) tcp_snd_cwnd_set(tp, nv_min_cwnd); } } /* Extract info for Tcp socket info provided via netlink */ static size_t tcpnv_get_info(struct sock *sk, u32 ext, int *attr, union tcp_cc_info *info) { const struct tcpnv *ca = inet_csk_ca(sk); if (ext & (1 << (INET_DIAG_VEGASINFO - 1))) { info->vegas.tcpv_enabled = 1; info->vegas.tcpv_rttcnt = ca->nv_rtt_cnt; info->vegas.tcpv_rtt = ca->nv_last_rtt; info->vegas.tcpv_minrtt = ca->nv_min_rtt; *attr = INET_DIAG_VEGASINFO; return sizeof(struct tcpvegas_info); } return 0; } static struct tcp_congestion_ops tcpnv __read_mostly = { .init = tcpnv_init, .ssthresh = tcpnv_recalc_ssthresh, .cong_avoid = tcpnv_cong_avoid, .set_state = tcpnv_state, .undo_cwnd = tcp_reno_undo_cwnd, .pkts_acked = tcpnv_acked, .get_info = tcpnv_get_info, .owner = THIS_MODULE, .name = "nv", }; static int __init tcpnv_register(void) { BUILD_BUG_ON(sizeof(struct tcpnv) > ICSK_CA_PRIV_SIZE); return tcp_register_congestion_control(&tcpnv); } static void __exit tcpnv_unregister(void) { tcp_unregister_congestion_control(&tcpnv); } module_init(tcpnv_register); module_exit(tcpnv_unregister); MODULE_AUTHOR("Lawrence Brakmo"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("TCP NV"); MODULE_VERSION("1.0");
linux-master
net/ipv4/tcp_nv.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * IPV4 GSO/GRO offload support * Linux INET implementation * * GRE GSO support */ #include <linux/skbuff.h> #include <linux/init.h> #include <net/protocol.h> #include <net/gre.h> #include <net/gro.h> #include <net/gso.h> static struct sk_buff *gre_gso_segment(struct sk_buff *skb, netdev_features_t features) { int tnl_hlen = skb_inner_mac_header(skb) - skb_transport_header(skb); bool need_csum, offload_csum, gso_partial, need_ipsec; struct sk_buff *segs = ERR_PTR(-EINVAL); u16 mac_offset = skb->mac_header; __be16 protocol = skb->protocol; u16 mac_len = skb->mac_len; int gre_offset, outer_hlen; if (!skb->encapsulation) goto out; if (unlikely(tnl_hlen < sizeof(struct gre_base_hdr))) goto out; if (unlikely(!pskb_may_pull(skb, tnl_hlen))) goto out; /* setup inner skb. */ skb->encapsulation = 0; SKB_GSO_CB(skb)->encap_level = 0; __skb_pull(skb, tnl_hlen); skb_reset_mac_header(skb); skb_set_network_header(skb, skb_inner_network_offset(skb)); skb->mac_len = skb_inner_network_offset(skb); skb->protocol = skb->inner_protocol; need_csum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_GRE_CSUM); skb->encap_hdr_csum = need_csum; features &= skb->dev->hw_enc_features; if (need_csum) features &= ~NETIF_F_SCTP_CRC; need_ipsec = skb_dst(skb) && dst_xfrm(skb_dst(skb)); /* Try to offload checksum if possible */ offload_csum = !!(need_csum && !need_ipsec && (skb->dev->features & NETIF_F_HW_CSUM)); /* segment inner packet. */ segs = skb_mac_gso_segment(skb, features); if (IS_ERR_OR_NULL(segs)) { skb_gso_error_unwind(skb, protocol, tnl_hlen, mac_offset, mac_len); goto out; } gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL); outer_hlen = skb_tnl_header_len(skb); gre_offset = outer_hlen - tnl_hlen; skb = segs; do { struct gre_base_hdr *greh; __sum16 *pcsum; /* Set up inner headers if we are offloading inner checksum */ if (skb->ip_summed == CHECKSUM_PARTIAL) { skb_reset_inner_headers(skb); skb->encapsulation = 1; } skb->mac_len = mac_len; skb->protocol = protocol; __skb_push(skb, outer_hlen); skb_reset_mac_header(skb); skb_set_network_header(skb, mac_len); skb_set_transport_header(skb, gre_offset); if (!need_csum) continue; greh = (struct gre_base_hdr *)skb_transport_header(skb); pcsum = (__sum16 *)(greh + 1); if (gso_partial && skb_is_gso(skb)) { unsigned int partial_adj; /* Adjust checksum to account for the fact that * the partial checksum is based on actual size * whereas headers should be based on MSS size. */ partial_adj = skb->len + skb_headroom(skb) - SKB_GSO_CB(skb)->data_offset - skb_shinfo(skb)->gso_size; *pcsum = ~csum_fold((__force __wsum)htonl(partial_adj)); } else { *pcsum = 0; } *(pcsum + 1) = 0; if (skb->encapsulation || !offload_csum) { *pcsum = gso_make_checksum(skb, 0); } else { skb->ip_summed = CHECKSUM_PARTIAL; skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = sizeof(*greh); } } while ((skb = skb->next)); out: return segs; } static struct sk_buff *gre_gro_receive(struct list_head *head, struct sk_buff *skb) { struct sk_buff *pp = NULL; struct sk_buff *p; const struct gre_base_hdr *greh; unsigned int hlen, grehlen; unsigned int off; int flush = 1; struct packet_offload *ptype; __be16 type; if (NAPI_GRO_CB(skb)->encap_mark) goto out; NAPI_GRO_CB(skb)->encap_mark = 1; off = skb_gro_offset(skb); hlen = off + sizeof(*greh); greh = skb_gro_header(skb, hlen, off); if (unlikely(!greh)) goto out; /* Only support version 0 and K (key), C (csum) flags. Note that * although the support for the S (seq#) flag can be added easily * for GRO, this is problematic for GSO hence can not be enabled * here because a GRO pkt may end up in the forwarding path, thus * requiring GSO support to break it up correctly. */ if ((greh->flags & ~(GRE_KEY|GRE_CSUM)) != 0) goto out; /* We can only support GRE_CSUM if we can track the location of * the GRE header. In the case of FOU/GUE we cannot because the * outer UDP header displaces the GRE header leaving us in a state * of limbo. */ if ((greh->flags & GRE_CSUM) && NAPI_GRO_CB(skb)->is_fou) goto out; type = greh->protocol; ptype = gro_find_receive_by_type(type); if (!ptype) goto out; grehlen = GRE_HEADER_SECTION; if (greh->flags & GRE_KEY) grehlen += GRE_HEADER_SECTION; if (greh->flags & GRE_CSUM) grehlen += GRE_HEADER_SECTION; hlen = off + grehlen; if (skb_gro_header_hard(skb, hlen)) { greh = skb_gro_header_slow(skb, hlen, off); if (unlikely(!greh)) goto out; } /* Don't bother verifying checksum if we're going to flush anyway. */ if ((greh->flags & GRE_CSUM) && !NAPI_GRO_CB(skb)->flush) { if (skb_gro_checksum_simple_validate(skb)) goto out; skb_gro_checksum_try_convert(skb, IPPROTO_GRE, null_compute_pseudo); } list_for_each_entry(p, head, list) { const struct gre_base_hdr *greh2; if (!NAPI_GRO_CB(p)->same_flow) continue; /* The following checks are needed to ensure only pkts * from the same tunnel are considered for aggregation. * The criteria for "the same tunnel" includes: * 1) same version (we only support version 0 here) * 2) same protocol (we only support ETH_P_IP for now) * 3) same set of flags * 4) same key if the key field is present. */ greh2 = (struct gre_base_hdr *)(p->data + off); if (greh2->flags != greh->flags || greh2->protocol != greh->protocol) { NAPI_GRO_CB(p)->same_flow = 0; continue; } if (greh->flags & GRE_KEY) { /* compare keys */ if (*(__be32 *)(greh2+1) != *(__be32 *)(greh+1)) { NAPI_GRO_CB(p)->same_flow = 0; continue; } } } skb_gro_pull(skb, grehlen); /* Adjusted NAPI_GRO_CB(skb)->csum after skb_gro_pull()*/ skb_gro_postpull_rcsum(skb, greh, grehlen); pp = call_gro_receive(ptype->callbacks.gro_receive, head, skb); flush = 0; out: skb_gro_flush_final(skb, pp, flush); return pp; } static int gre_gro_complete(struct sk_buff *skb, int nhoff) { struct gre_base_hdr *greh = (struct gre_base_hdr *)(skb->data + nhoff); struct packet_offload *ptype; unsigned int grehlen = sizeof(*greh); int err = -ENOENT; __be16 type; skb->encapsulation = 1; skb_shinfo(skb)->gso_type = SKB_GSO_GRE; type = greh->protocol; if (greh->flags & GRE_KEY) grehlen += GRE_HEADER_SECTION; if (greh->flags & GRE_CSUM) grehlen += GRE_HEADER_SECTION; ptype = gro_find_complete_by_type(type); if (ptype) err = ptype->callbacks.gro_complete(skb, nhoff + grehlen); skb_set_inner_mac_header(skb, nhoff + grehlen); return err; } static const struct net_offload gre_offload = { .callbacks = { .gso_segment = gre_gso_segment, .gro_receive = gre_gro_receive, .gro_complete = gre_gro_complete, }, }; static int __init gre_offload_init(void) { int err; err = inet_add_offload(&gre_offload, IPPROTO_GRE); #if IS_ENABLED(CONFIG_IPV6) if (err) return err; err = inet6_add_offload(&gre_offload, IPPROTO_GRE); if (err) inet_del_offload(&gre_offload, IPPROTO_GRE); #endif return err; } device_initcall(gre_offload_init);
linux-master
net/ipv4/gre_offload.c
// SPDX-License-Identifier: GPL-2.0 /* * Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or * user-supplied information to configure own IP address and routes. * * Copyright (C) 1996-1998 Martin Mares <[email protected]> * * Derived from network configuration code in fs/nfs/nfsroot.c, * originally Copyright (C) 1995, 1996 Gero Kuhlmann and me. * * BOOTP rewritten to construct and analyse packets itself instead * of misusing the IP layer. num_bugs_causing_wrong_arp_replies--; * -- MJ, December 1998 * * Fixed ip_auto_config_setup calling at startup in the new "Linker Magic" * initialization scheme. * - Arnaldo Carvalho de Melo <[email protected]>, 08/11/1999 * * DHCP support added. To users this looks like a whole separate * protocol, but we know it's just a bag on the side of BOOTP. * -- Chip Salzenberg <[email protected]>, May 2000 * * Ported DHCP support from 2.2.16 to 2.4.0-test4 * -- Eric Biederman <[email protected]>, 30 Aug 2000 * * Merged changes from 2.2.19 into 2.4.3 * -- Eric Biederman <[email protected]>, 22 April Aug 2001 * * Multiple Nameservers in /proc/net/pnp * -- Josef Siemes <[email protected]>, Aug 2002 * * NTP servers in /proc/net/ipconfig/ntp_servers * -- Chris Novakovic <[email protected]>, April 2018 */ #include <linux/types.h> #include <linux/string.h> #include <linux/kernel.h> #include <linux/jiffies.h> #include <linux/random.h> #include <linux/init.h> #include <linux/utsname.h> #include <linux/in.h> #include <linux/if.h> #include <linux/inet.h> #include <linux/inetdevice.h> #include <linux/netdevice.h> #include <linux/if_arp.h> #include <linux/skbuff.h> #include <linux/ip.h> #include <linux/socket.h> #include <linux/route.h> #include <linux/udp.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/major.h> #include <linux/root_dev.h> #include <linux/delay.h> #include <linux/nfs_fs.h> #include <linux/slab.h> #include <linux/export.h> #include <net/net_namespace.h> #include <net/arp.h> #include <net/ip.h> #include <net/ipconfig.h> #include <net/route.h> #include <linux/uaccess.h> #include <net/checksum.h> #include <asm/processor.h> #if defined(CONFIG_IP_PNP_DHCP) #define IPCONFIG_DHCP #endif #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP) #define IPCONFIG_BOOTP #endif #if defined(CONFIG_IP_PNP_RARP) #define IPCONFIG_RARP #endif #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP) #define IPCONFIG_DYNAMIC #endif /* Define the friendly delay before and after opening net devices */ #define CONF_POST_OPEN 10 /* After opening: 10 msecs */ /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */ #define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */ #define CONF_SEND_RETRIES 6 /* Send six requests per open */ #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */ #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */ #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */ #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */ #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers - '3' from resolv.h */ #define CONF_NTP_SERVERS_MAX 3 /* Maximum number of NTP servers */ #define NONE cpu_to_be32(INADDR_NONE) #define ANY cpu_to_be32(INADDR_ANY) /* Wait for carrier timeout default in seconds */ static unsigned int carrier_timeout = 120; /* * Public IP configuration */ /* This is used by platforms which might be able to set the ipconfig * variables using firmware environment vars. If this is set, it will * ignore such firmware variables. */ int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */ static int ic_enable __initdata; /* IP config enabled? */ /* Protocol choice */ int ic_proto_enabled __initdata = 0 #ifdef IPCONFIG_BOOTP | IC_BOOTP #endif #ifdef CONFIG_IP_PNP_DHCP | IC_USE_DHCP #endif #ifdef IPCONFIG_RARP | IC_RARP #endif ; static int ic_host_name_set __initdata; /* Host name set by us? */ __be32 ic_myaddr = NONE; /* My IP address */ static __be32 ic_netmask = NONE; /* Netmask for local subnet */ __be32 ic_gateway = NONE; /* Gateway IP address */ #ifdef IPCONFIG_DYNAMIC static __be32 ic_addrservaddr = NONE; /* IP Address of the IP addresses'server */ #endif __be32 ic_servaddr = NONE; /* Boot server IP address */ __be32 root_server_addr = NONE; /* Address of NFS server */ u8 root_server_path[256] = { 0, }; /* Path to mount as root */ /* vendor class identifier */ static char vendor_class_identifier[253] __initdata; #if defined(CONFIG_IP_PNP_DHCP) static char dhcp_client_identifier[253] __initdata; #endif /* Persistent data: */ #ifdef IPCONFIG_DYNAMIC static int ic_proto_used; /* Protocol used, if any */ #else #define ic_proto_used 0 #endif static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */ static __be32 ic_ntp_servers[CONF_NTP_SERVERS_MAX]; /* NTP server IP addresses */ static u8 ic_domain[64]; /* DNS (not NIS) domain name */ /* * Private state. */ /* Name of user-selected boot device */ static char user_dev_name[IFNAMSIZ] __initdata = { 0, }; /* Protocols supported by available interfaces */ static int ic_proto_have_if __initdata; /* MTU for boot device */ static int ic_dev_mtu __initdata; #ifdef IPCONFIG_DYNAMIC static DEFINE_SPINLOCK(ic_recv_lock); static volatile int ic_got_reply __initdata; /* Proto(s) that replied */ #endif #ifdef IPCONFIG_DHCP static int ic_dhcp_msgtype __initdata; /* DHCP msg type received */ #endif /* * Network devices */ struct ic_device { struct ic_device *next; struct net_device *dev; unsigned short flags; short able; __be32 xid; }; static struct ic_device *ic_first_dev __initdata; /* List of open device */ static struct ic_device *ic_dev __initdata; /* Selected device */ static bool __init ic_is_init_dev(struct net_device *dev) { if (dev->flags & IFF_LOOPBACK) return false; return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) : (!(dev->flags & IFF_LOOPBACK) && (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) && strncmp(dev->name, "dummy", 5)); } static int __init ic_open_devs(void) { struct ic_device *d, **last; struct net_device *dev; unsigned short oflags; unsigned long start, next_msg; last = &ic_first_dev; rtnl_lock(); /* bring loopback device up first */ for_each_netdev(&init_net, dev) { if (!(dev->flags & IFF_LOOPBACK)) continue; if (dev_change_flags(dev, dev->flags | IFF_UP, NULL) < 0) pr_err("IP-Config: Failed to open %s\n", dev->name); } for_each_netdev(&init_net, dev) { if (ic_is_init_dev(dev)) { int able = 0; if (dev->mtu >= 364) able |= IC_BOOTP; else pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n", dev->name, dev->mtu); if (!(dev->flags & IFF_NOARP)) able |= IC_RARP; able &= ic_proto_enabled; if (ic_proto_enabled && !able) continue; oflags = dev->flags; if (dev_change_flags(dev, oflags | IFF_UP, NULL) < 0) { pr_err("IP-Config: Failed to open %s\n", dev->name); continue; } if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) { rtnl_unlock(); return -ENOMEM; } d->dev = dev; *last = d; last = &d->next; d->flags = oflags; d->able = able; if (able & IC_BOOTP) get_random_bytes(&d->xid, sizeof(__be32)); else d->xid = 0; ic_proto_have_if |= able; pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n", dev->name, able, d->xid); } } /* Devices with a complex topology like SFP ethernet interfaces needs * the rtnl_lock at init. The carrier wait-loop must therefore run * without holding it. */ rtnl_unlock(); /* no point in waiting if we could not bring up at least one device */ if (!ic_first_dev) goto have_carrier; /* wait for a carrier on at least one device */ start = jiffies; next_msg = start + msecs_to_jiffies(20000); while (time_before(jiffies, start + msecs_to_jiffies(carrier_timeout * 1000))) { int wait, elapsed; rtnl_lock(); for_each_netdev(&init_net, dev) if (ic_is_init_dev(dev) && netif_carrier_ok(dev)) { rtnl_unlock(); goto have_carrier; } rtnl_unlock(); msleep(1); if (time_before(jiffies, next_msg)) continue; elapsed = jiffies_to_msecs(jiffies - start); wait = (carrier_timeout * 1000 - elapsed + 500) / 1000; pr_info("Waiting up to %d more seconds for network.\n", wait); next_msg = jiffies + msecs_to_jiffies(20000); } have_carrier: *last = NULL; if (!ic_first_dev) { if (user_dev_name[0]) pr_err("IP-Config: Device `%s' not found\n", user_dev_name); else pr_err("IP-Config: No network devices available\n"); return -ENODEV; } return 0; } /* Close all network interfaces except the one we've autoconfigured, and its * lowers, in case it's a stacked virtual interface. */ static void __init ic_close_devs(void) { struct net_device *selected_dev = ic_dev ? ic_dev->dev : NULL; struct ic_device *d, *next; struct net_device *dev; rtnl_lock(); next = ic_first_dev; while ((d = next)) { bool bring_down = (d != ic_dev); struct net_device *lower; struct list_head *iter; next = d->next; dev = d->dev; if (selected_dev) { netdev_for_each_lower_dev(selected_dev, lower, iter) { if (dev == lower) { bring_down = false; break; } } } if (bring_down) { pr_debug("IP-Config: Downing %s\n", dev->name); dev_change_flags(dev, d->flags, NULL); } kfree(d); } rtnl_unlock(); } /* * Interface to various network functions. */ static inline void set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port) { sin->sin_family = AF_INET; sin->sin_addr.s_addr = addr; sin->sin_port = port; } /* * Set up interface addresses and routes. */ static int __init ic_setup_if(void) { struct ifreq ir; struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr; int err; memset(&ir, 0, sizeof(ir)); strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name); set_sockaddr(sin, ic_myaddr, 0); if ((err = devinet_ioctl(&init_net, SIOCSIFADDR, &ir)) < 0) { pr_err("IP-Config: Unable to set interface address (%d)\n", err); return -1; } set_sockaddr(sin, ic_netmask, 0); if ((err = devinet_ioctl(&init_net, SIOCSIFNETMASK, &ir)) < 0) { pr_err("IP-Config: Unable to set interface netmask (%d)\n", err); return -1; } set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0); if ((err = devinet_ioctl(&init_net, SIOCSIFBRDADDR, &ir)) < 0) { pr_err("IP-Config: Unable to set interface broadcast address (%d)\n", err); return -1; } /* Handle the case where we need non-standard MTU on the boot link (a network * using jumbo frames, for instance). If we can't set the mtu, don't error * out, we'll try to muddle along. */ if (ic_dev_mtu != 0) { rtnl_lock(); if ((err = dev_set_mtu(ic_dev->dev, ic_dev_mtu)) < 0) pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n", ic_dev_mtu, err); rtnl_unlock(); } return 0; } static int __init ic_setup_routes(void) { /* No need to setup device routes, only the default route... */ if (ic_gateway != NONE) { struct rtentry rm; int err; memset(&rm, 0, sizeof(rm)); if ((ic_gateway ^ ic_myaddr) & ic_netmask) { pr_err("IP-Config: Gateway not on directly connected network\n"); return -1; } set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0); set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0); set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0); rm.rt_flags = RTF_UP | RTF_GATEWAY; if ((err = ip_rt_ioctl(&init_net, SIOCADDRT, &rm)) < 0) { pr_err("IP-Config: Cannot add default route (%d)\n", err); return -1; } } return 0; } /* * Fill in default values for all missing parameters. */ static int __init ic_defaults(void) { /* * At this point we have no userspace running so need not * claim locks on system_utsname */ if (!ic_host_name_set) sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr); if (root_server_addr == NONE) root_server_addr = ic_servaddr; if (ic_netmask == NONE) { if (IN_CLASSA(ntohl(ic_myaddr))) ic_netmask = htonl(IN_CLASSA_NET); else if (IN_CLASSB(ntohl(ic_myaddr))) ic_netmask = htonl(IN_CLASSB_NET); else if (IN_CLASSC(ntohl(ic_myaddr))) ic_netmask = htonl(IN_CLASSC_NET); else if (IN_CLASSE(ntohl(ic_myaddr))) ic_netmask = htonl(IN_CLASSE_NET); else { pr_err("IP-Config: Unable to guess netmask for address %pI4\n", &ic_myaddr); return -1; } pr_notice("IP-Config: Guessing netmask %pI4\n", &ic_netmask); } return 0; } /* * RARP support. */ #ifdef IPCONFIG_RARP static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev); static struct packet_type rarp_packet_type __initdata = { .type = cpu_to_be16(ETH_P_RARP), .func = ic_rarp_recv, }; static inline void __init ic_rarp_init(void) { dev_add_pack(&rarp_packet_type); } static inline void __init ic_rarp_cleanup(void) { dev_remove_pack(&rarp_packet_type); } /* * Process received RARP packet. */ static int __init ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct arphdr *rarp; unsigned char *rarp_ptr; __be32 sip, tip; unsigned char *tha; /* t for "target" */ struct ic_device *d; if (!net_eq(dev_net(dev), &init_net)) goto drop; skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) return NET_RX_DROP; if (!pskb_may_pull(skb, sizeof(struct arphdr))) goto drop; /* Basic sanity checks can be done without the lock. */ rarp = (struct arphdr *)skb_transport_header(skb); /* If this test doesn't pass, it's not IP, or we should * ignore it anyway. */ if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd)) goto drop; /* If it's not a RARP reply, delete it. */ if (rarp->ar_op != htons(ARPOP_RREPLY)) goto drop; /* If it's not Ethernet, delete it. */ if (rarp->ar_pro != htons(ETH_P_IP)) goto drop; if (!pskb_may_pull(skb, arp_hdr_len(dev))) goto drop; /* OK, it is all there and looks valid, process... */ rarp = (struct arphdr *)skb_transport_header(skb); rarp_ptr = (unsigned char *) (rarp + 1); /* One reply at a time, please. */ spin_lock(&ic_recv_lock); /* If we already have a reply, just drop the packet */ if (ic_got_reply) goto drop_unlock; /* Find the ic_device that the packet arrived on */ d = ic_first_dev; while (d && d->dev != dev) d = d->next; if (!d) goto drop_unlock; /* should never happen */ /* Extract variable-width fields */ rarp_ptr += dev->addr_len; memcpy(&sip, rarp_ptr, 4); rarp_ptr += 4; tha = rarp_ptr; rarp_ptr += dev->addr_len; memcpy(&tip, rarp_ptr, 4); /* Discard packets which are not meant for us. */ if (memcmp(tha, dev->dev_addr, dev->addr_len)) goto drop_unlock; /* Discard packets which are not from specified server. */ if (ic_servaddr != NONE && ic_servaddr != sip) goto drop_unlock; /* We have a winner! */ ic_dev = d; if (ic_myaddr == NONE) ic_myaddr = tip; ic_servaddr = sip; ic_addrservaddr = sip; ic_got_reply = IC_RARP; drop_unlock: /* Show's over. Nothing to see here. */ spin_unlock(&ic_recv_lock); drop: /* Throw the packet out. */ kfree_skb(skb); return 0; } /* * Send RARP request packet over a single interface. */ static void __init ic_rarp_send_if(struct ic_device *d) { struct net_device *dev = d->dev; arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL, dev->dev_addr, dev->dev_addr); } #endif /* * Predefine Nameservers */ static inline void __init ic_nameservers_predef(void) { int i; for (i = 0; i < CONF_NAMESERVERS_MAX; i++) ic_nameservers[i] = NONE; } /* Predefine NTP servers */ static inline void __init ic_ntp_servers_predef(void) { int i; for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) ic_ntp_servers[i] = NONE; } /* * DHCP/BOOTP support. */ #ifdef IPCONFIG_BOOTP struct bootp_pkt { /* BOOTP packet format */ struct iphdr iph; /* IP header */ struct udphdr udph; /* UDP header */ u8 op; /* 1=request, 2=reply */ u8 htype; /* HW address type */ u8 hlen; /* HW address length */ u8 hops; /* Used only by gateways */ __be32 xid; /* Transaction ID */ __be16 secs; /* Seconds since we started */ __be16 flags; /* Just what it says */ __be32 client_ip; /* Client's IP address if known */ __be32 your_ip; /* Assigned IP address */ __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */ __be32 relay_ip; /* IP address of BOOTP relay */ u8 hw_addr[16]; /* Client's HW address */ u8 serv_name[64]; /* Server host name */ u8 boot_file[128]; /* Name of boot file */ u8 exten[312]; /* DHCP options / BOOTP vendor extensions */ }; /* packet ops */ #define BOOTP_REQUEST 1 #define BOOTP_REPLY 2 /* DHCP message types */ #define DHCPDISCOVER 1 #define DHCPOFFER 2 #define DHCPREQUEST 3 #define DHCPDECLINE 4 #define DHCPACK 5 #define DHCPNAK 6 #define DHCPRELEASE 7 #define DHCPINFORM 8 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev); static struct packet_type bootp_packet_type __initdata = { .type = cpu_to_be16(ETH_P_IP), .func = ic_bootp_recv, }; /* DHCPACK can overwrite DNS if fallback was set upon first BOOTP reply */ static int ic_nameservers_fallback __initdata; /* * Initialize DHCP/BOOTP extension fields in the request. */ static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 }; #ifdef IPCONFIG_DHCP static void __init ic_dhcp_init_options(u8 *options, struct ic_device *d) { u8 mt = ((ic_servaddr == NONE) ? DHCPDISCOVER : DHCPREQUEST); u8 *e = options; int len; pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name); memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */ e += 4; *e++ = 53; /* DHCP message type */ *e++ = 1; *e++ = mt; if (mt == DHCPREQUEST) { *e++ = 54; /* Server ID (IP address) */ *e++ = 4; memcpy(e, &ic_servaddr, 4); e += 4; *e++ = 50; /* Requested IP address */ *e++ = 4; memcpy(e, &ic_myaddr, 4); e += 4; } /* always? */ { static const u8 ic_req_params[] = { 1, /* Subnet mask */ 3, /* Default gateway */ 6, /* DNS server */ 12, /* Host name */ 15, /* Domain name */ 17, /* Boot path */ 26, /* MTU */ 40, /* NIS domain name */ 42, /* NTP servers */ }; *e++ = 55; /* Parameter request list */ *e++ = sizeof(ic_req_params); memcpy(e, ic_req_params, sizeof(ic_req_params)); e += sizeof(ic_req_params); if (ic_host_name_set) { *e++ = 12; /* host-name */ len = strlen(utsname()->nodename); *e++ = len; memcpy(e, utsname()->nodename, len); e += len; } if (*vendor_class_identifier) { pr_info("DHCP: sending class identifier \"%s\"\n", vendor_class_identifier); *e++ = 60; /* Class-identifier */ len = strlen(vendor_class_identifier); *e++ = len; memcpy(e, vendor_class_identifier, len); e += len; } len = strlen(dhcp_client_identifier + 1); /* the minimum length of identifier is 2, include 1 byte type, * and can not be larger than the length of options */ if (len >= 1 && len < 312 - (e - options) - 1) { *e++ = 61; *e++ = len + 1; memcpy(e, dhcp_client_identifier, len + 1); e += len + 1; } } *e++ = 255; /* End of the list */ } #endif /* IPCONFIG_DHCP */ static void __init ic_bootp_init_ext(u8 *e) { memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */ e += 4; *e++ = 1; /* Subnet mask request */ *e++ = 4; e += 4; *e++ = 3; /* Default gateway request */ *e++ = 4; e += 4; #if CONF_NAMESERVERS_MAX > 0 *e++ = 6; /* (DNS) name server request */ *e++ = 4 * CONF_NAMESERVERS_MAX; e += 4 * CONF_NAMESERVERS_MAX; #endif *e++ = 12; /* Host name request */ *e++ = 32; e += 32; *e++ = 40; /* NIS Domain name request */ *e++ = 32; e += 32; *e++ = 17; /* Boot path */ *e++ = 40; e += 40; *e++ = 57; /* set extension buffer size for reply */ *e++ = 2; *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */ *e++ = 150; *e++ = 255; /* End of the list */ } /* * Initialize the DHCP/BOOTP mechanism. */ static inline void __init ic_bootp_init(void) { /* Re-initialise all name servers and NTP servers to NONE, in case any * were set via the "ip=" or "nfsaddrs=" kernel command line parameters: * any IP addresses specified there will already have been decoded but * are no longer needed */ ic_nameservers_predef(); ic_ntp_servers_predef(); dev_add_pack(&bootp_packet_type); } /* * DHCP/BOOTP cleanup. */ static inline void __init ic_bootp_cleanup(void) { dev_remove_pack(&bootp_packet_type); } /* * Send DHCP/BOOTP request to single interface. */ static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff) { struct net_device *dev = d->dev; struct sk_buff *skb; struct bootp_pkt *b; struct iphdr *h; int hlen = LL_RESERVED_SPACE(dev); int tlen = dev->needed_tailroom; /* Allocate packet */ skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15, GFP_KERNEL); if (!skb) return; skb_reserve(skb, hlen); b = skb_put_zero(skb, sizeof(struct bootp_pkt)); /* Construct IP header */ skb_reset_network_header(skb); h = ip_hdr(skb); h->version = 4; h->ihl = 5; h->tot_len = htons(sizeof(struct bootp_pkt)); h->frag_off = htons(IP_DF); h->ttl = 64; h->protocol = IPPROTO_UDP; h->daddr = htonl(INADDR_BROADCAST); h->check = ip_fast_csum((unsigned char *) h, h->ihl); /* Construct UDP header */ b->udph.source = htons(68); b->udph.dest = htons(67); b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr)); /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */ /* Construct DHCP/BOOTP header */ b->op = BOOTP_REQUEST; if (dev->type < 256) /* check for false types */ b->htype = dev->type; else if (dev->type == ARPHRD_FDDI) b->htype = ARPHRD_ETHER; else { pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name); b->htype = dev->type; /* can cause undefined behavior */ } /* server_ip and your_ip address are both already zero per RFC2131 */ b->hlen = dev->addr_len; memcpy(b->hw_addr, dev->dev_addr, dev->addr_len); b->secs = htons(jiffies_diff / HZ); b->xid = d->xid; /* add DHCP options or BOOTP extensions */ #ifdef IPCONFIG_DHCP if (ic_proto_enabled & IC_USE_DHCP) ic_dhcp_init_options(b->exten, d); else #endif ic_bootp_init_ext(b->exten); /* Chain packet down the line... */ skb->dev = dev; skb->protocol = htons(ETH_P_IP); if (dev_hard_header(skb, dev, ntohs(skb->protocol), dev->broadcast, dev->dev_addr, skb->len) < 0) { kfree_skb(skb); printk("E"); return; } if (dev_queue_xmit(skb) < 0) printk("E"); } /* * Copy BOOTP-supplied string */ static int __init ic_bootp_string(char *dest, char *src, int len, int max) { if (!len) return 0; if (len > max-1) len = max-1; memcpy(dest, src, len); dest[len] = '\0'; return 1; } /* * Process BOOTP extensions. */ static void __init ic_do_bootp_ext(u8 *ext) { u8 servers; int i; __be16 mtu; u8 *c; pr_debug("DHCP/BOOTP: Got extension %d:", *ext); for (c=ext+2; c<ext+2+ext[1]; c++) pr_debug(" %02x", *c); pr_debug("\n"); switch (*ext++) { case 1: /* Subnet mask */ if (ic_netmask == NONE) memcpy(&ic_netmask, ext+1, 4); break; case 3: /* Default gateway */ if (ic_gateway == NONE) memcpy(&ic_gateway, ext+1, 4); break; case 6: /* DNS server */ servers= *ext/4; if (servers > CONF_NAMESERVERS_MAX) servers = CONF_NAMESERVERS_MAX; for (i = 0; i < servers; i++) { if (ic_nameservers[i] == NONE || ic_nameservers_fallback) memcpy(&ic_nameservers[i], ext+1+4*i, 4); } break; case 12: /* Host name */ if (!ic_host_name_set) { ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN); ic_host_name_set = 1; } break; case 15: /* Domain name (DNS) */ if (!ic_domain[0]) ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain)); break; case 17: /* Root path */ if (!root_server_path[0]) ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path)); break; case 26: /* Interface MTU */ memcpy(&mtu, ext+1, sizeof(mtu)); ic_dev_mtu = ntohs(mtu); break; case 40: /* NIS Domain name (_not_ DNS) */ ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN); break; case 42: /* NTP servers */ servers = *ext / 4; if (servers > CONF_NTP_SERVERS_MAX) servers = CONF_NTP_SERVERS_MAX; for (i = 0; i < servers; i++) { if (ic_ntp_servers[i] == NONE) memcpy(&ic_ntp_servers[i], ext+1+4*i, 4); } break; } } /* * Receive BOOTP reply. */ static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct bootp_pkt *b; struct iphdr *h; struct ic_device *d; int len, ext_len; if (!net_eq(dev_net(dev), &init_net)) goto drop; /* Perform verifications before taking the lock. */ if (skb->pkt_type == PACKET_OTHERHOST) goto drop; skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) return NET_RX_DROP; if (!pskb_may_pull(skb, sizeof(struct iphdr) + sizeof(struct udphdr))) goto drop; b = (struct bootp_pkt *)skb_network_header(skb); h = &b->iph; if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP) goto drop; /* Fragments are not supported */ if (ip_is_fragment(h)) { net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n"); goto drop; } if (skb->len < ntohs(h->tot_len)) goto drop; if (ip_fast_csum((char *) h, h->ihl)) goto drop; if (b->udph.source != htons(67) || b->udph.dest != htons(68)) goto drop; if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr)) goto drop; len = ntohs(b->udph.len) - sizeof(struct udphdr); ext_len = len - (sizeof(*b) - sizeof(struct iphdr) - sizeof(struct udphdr) - sizeof(b->exten)); if (ext_len < 0) goto drop; /* Ok the front looks good, make sure we can get at the rest. */ if (!pskb_may_pull(skb, skb->len)) goto drop; b = (struct bootp_pkt *)skb_network_header(skb); h = &b->iph; /* One reply at a time, please. */ spin_lock(&ic_recv_lock); /* If we already have a reply, just drop the packet */ if (ic_got_reply) goto drop_unlock; /* Find the ic_device that the packet arrived on */ d = ic_first_dev; while (d && d->dev != dev) d = d->next; if (!d) goto drop_unlock; /* should never happen */ /* Is it a reply to our BOOTP request? */ if (b->op != BOOTP_REPLY || b->xid != d->xid) { net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n", d->dev->name, b->op, b->xid); goto drop_unlock; } /* Parse extensions */ if (ext_len >= 4 && !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */ u8 *end = (u8 *) b + ntohs(b->iph.tot_len); u8 *ext; #ifdef IPCONFIG_DHCP if (ic_proto_enabled & IC_USE_DHCP) { __be32 server_id = NONE; int mt = 0; ext = &b->exten[4]; while (ext < end && *ext != 0xff) { u8 *opt = ext++; if (*opt == 0) /* Padding */ continue; ext += *ext + 1; if (ext >= end) break; switch (*opt) { case 53: /* Message type */ if (opt[1]) mt = opt[2]; break; case 54: /* Server ID (IP address) */ if (opt[1] >= 4) memcpy(&server_id, opt + 2, 4); break; } } pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name); switch (mt) { case DHCPOFFER: /* While in the process of accepting one offer, * ignore all others. */ if (ic_myaddr != NONE) goto drop_unlock; /* Let's accept that offer. */ ic_myaddr = b->your_ip; ic_servaddr = server_id; pr_debug("DHCP: Offered address %pI4 by server %pI4\n", &ic_myaddr, &b->iph.saddr); /* The DHCP indicated server address takes * precedence over the bootp header one if * they are different. */ if ((server_id != NONE) && (b->server_ip != server_id)) b->server_ip = ic_servaddr; break; case DHCPACK: if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0) goto drop_unlock; /* Yeah! */ break; default: /* Urque. Forget it*/ ic_myaddr = NONE; ic_servaddr = NONE; goto drop_unlock; } ic_dhcp_msgtype = mt; } #endif /* IPCONFIG_DHCP */ ext = &b->exten[4]; while (ext < end && *ext != 0xff) { u8 *opt = ext++; if (*opt == 0) /* Padding */ continue; ext += *ext + 1; if (ext < end) ic_do_bootp_ext(opt); } } /* We have a winner! */ ic_dev = d; ic_myaddr = b->your_ip; ic_servaddr = b->server_ip; ic_addrservaddr = b->iph.saddr; if (ic_gateway == NONE && b->relay_ip) ic_gateway = b->relay_ip; if (ic_nameservers[0] == NONE) { ic_nameservers[0] = ic_servaddr; ic_nameservers_fallback = 1; } ic_got_reply = IC_BOOTP; drop_unlock: /* Show's over. Nothing to see here. */ spin_unlock(&ic_recv_lock); drop: /* Throw the packet out. */ kfree_skb(skb); return 0; } #endif /* * Dynamic IP configuration -- DHCP, BOOTP, RARP. */ #ifdef IPCONFIG_DYNAMIC static int __init ic_dynamic(void) { int retries; struct ic_device *d; unsigned long start_jiffies, timeout, jiff; int do_bootp = ic_proto_have_if & IC_BOOTP; int do_rarp = ic_proto_have_if & IC_RARP; /* * If none of DHCP/BOOTP/RARP was selected, return with an error. * This routine gets only called when some pieces of information * are missing, and without DHCP/BOOTP/RARP we are unable to get it. */ if (!ic_proto_enabled) { pr_err("IP-Config: Incomplete network configuration information\n"); return -1; } #ifdef IPCONFIG_BOOTP if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP) pr_err("DHCP/BOOTP: No suitable device found\n"); #endif #ifdef IPCONFIG_RARP if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP) pr_err("RARP: No suitable device found\n"); #endif if (!ic_proto_have_if) /* Error message already printed */ return -1; /* * Setup protocols */ #ifdef IPCONFIG_BOOTP if (do_bootp) ic_bootp_init(); #endif #ifdef IPCONFIG_RARP if (do_rarp) ic_rarp_init(); #endif /* * Send requests and wait, until we get an answer. This loop * seems to be a terrible waste of CPU time, but actually there is * only one process running at all, so we don't need to use any * scheduler functions. * [Actually we could now, but the nothing else running note still * applies.. - AC] */ pr_notice("Sending %s%s%s requests .", do_bootp ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "", (do_bootp && do_rarp) ? " and " : "", do_rarp ? "RARP" : ""); start_jiffies = jiffies; d = ic_first_dev; retries = CONF_SEND_RETRIES; get_random_bytes(&timeout, sizeof(timeout)); timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM); for (;;) { #ifdef IPCONFIG_BOOTP if (do_bootp && (d->able & IC_BOOTP)) ic_bootp_send_if(d, jiffies - start_jiffies); #endif #ifdef IPCONFIG_RARP if (do_rarp && (d->able & IC_RARP)) ic_rarp_send_if(d); #endif if (!d->next) { jiff = jiffies + timeout; while (time_before(jiffies, jiff) && !ic_got_reply) schedule_timeout_uninterruptible(1); } #ifdef IPCONFIG_DHCP /* DHCP isn't done until we get a DHCPACK. */ if ((ic_got_reply & IC_BOOTP) && (ic_proto_enabled & IC_USE_DHCP) && ic_dhcp_msgtype != DHCPACK) { ic_got_reply = 0; /* continue on device that got the reply */ d = ic_dev; pr_cont(","); continue; } #endif /* IPCONFIG_DHCP */ if (ic_got_reply) { pr_cont(" OK\n"); break; } if ((d = d->next)) continue; if (! --retries) { pr_cont(" timed out!\n"); break; } d = ic_first_dev; timeout = timeout CONF_TIMEOUT_MULT; if (timeout > CONF_TIMEOUT_MAX) timeout = CONF_TIMEOUT_MAX; pr_cont("."); } #ifdef IPCONFIG_BOOTP if (do_bootp) ic_bootp_cleanup(); #endif #ifdef IPCONFIG_RARP if (do_rarp) ic_rarp_cleanup(); #endif if (!ic_got_reply) { ic_myaddr = NONE; return -1; } pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n", ((ic_got_reply & IC_RARP) ? "RARP" : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"), &ic_addrservaddr, &ic_myaddr); return 0; } #endif /* IPCONFIG_DYNAMIC */ #ifdef CONFIG_PROC_FS /* proc_dir_entry for /proc/net/ipconfig */ static struct proc_dir_entry *ipconfig_dir; /* Name servers: */ static int pnp_seq_show(struct seq_file *seq, void *v) { int i; if (ic_proto_used & IC_PROTO) seq_printf(seq, "#PROTO: %s\n", (ic_proto_used & IC_RARP) ? "RARP" : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP"); else seq_puts(seq, "#MANUAL\n"); if (ic_domain[0]) seq_printf(seq, "domain %s\n", ic_domain); for (i = 0; i < CONF_NAMESERVERS_MAX; i++) { if (ic_nameservers[i] != NONE) seq_printf(seq, "nameserver %pI4\n", &ic_nameservers[i]); } if (ic_servaddr != NONE) seq_printf(seq, "bootserver %pI4\n", &ic_servaddr); return 0; } /* Create the /proc/net/ipconfig directory */ static int __init ipconfig_proc_net_init(void) { ipconfig_dir = proc_net_mkdir(&init_net, "ipconfig", init_net.proc_net); if (!ipconfig_dir) return -ENOMEM; return 0; } /* Create a new file under /proc/net/ipconfig */ static int ipconfig_proc_net_create(const char *name, const struct proc_ops *proc_ops) { char *pname; struct proc_dir_entry *p; if (!ipconfig_dir) return -ENOMEM; pname = kasprintf(GFP_KERNEL, "%s%s", "ipconfig/", name); if (!pname) return -ENOMEM; p = proc_create(pname, 0444, init_net.proc_net, proc_ops); kfree(pname); if (!p) return -ENOMEM; return 0; } /* Write NTP server IP addresses to /proc/net/ipconfig/ntp_servers */ static int ntp_servers_show(struct seq_file *seq, void *v) { int i; for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) { if (ic_ntp_servers[i] != NONE) seq_printf(seq, "%pI4\n", &ic_ntp_servers[i]); } return 0; } DEFINE_PROC_SHOW_ATTRIBUTE(ntp_servers); #endif /* CONFIG_PROC_FS */ /* * Extract IP address from the parameter string if needed. Note that we * need to have root_server_addr set _before_ IPConfig gets called as it * can override it. */ __be32 __init root_nfs_parse_addr(char *name) { __be32 addr; int octets = 0; char *cp, *cq; cp = cq = name; while (octets < 4) { while (*cp >= '0' && *cp <= '9') cp++; if (cp == cq || cp - cq > 3) break; if (*cp == '.' || octets == 3) octets++; if (octets < 4) cp++; cq = cp; } if (octets == 4 && (*cp == ':' || *cp == '\0')) { if (*cp == ':') *cp++ = '\0'; addr = in_aton(name); memmove(name, cp, strlen(cp) + 1); } else addr = NONE; return addr; } #define DEVICE_WAIT_MAX 12 /* 12 seconds */ static int __init wait_for_devices(void) { int i; bool try_init_devs = true; for (i = 0; i < DEVICE_WAIT_MAX; i++) { struct net_device *dev; int found = 0; /* make sure deferred device probes are finished */ wait_for_device_probe(); rtnl_lock(); for_each_netdev(&init_net, dev) { if (ic_is_init_dev(dev)) { found = 1; break; } } rtnl_unlock(); if (found) return 0; if (try_init_devs && (ROOT_DEV == Root_NFS || ROOT_DEV == Root_CIFS)) { try_init_devs = false; wait_for_init_devices_probe(); } ssleep(1); } return -ENODEV; } /* * IP Autoconfig dispatcher. */ static int __init ip_auto_config(void) { __be32 addr; #ifdef IPCONFIG_DYNAMIC int retries = CONF_OPEN_RETRIES; #endif int err; unsigned int i, count; /* Initialise all name servers and NTP servers to NONE (but only if the * "ip=" or "nfsaddrs=" kernel command line parameters weren't decoded, * otherwise we'll overwrite the IP addresses specified there) */ if (ic_set_manually == 0) { ic_nameservers_predef(); ic_ntp_servers_predef(); } #ifdef CONFIG_PROC_FS proc_create_single("pnp", 0444, init_net.proc_net, pnp_seq_show); if (ipconfig_proc_net_init() == 0) ipconfig_proc_net_create("ntp_servers", &ntp_servers_proc_ops); #endif /* CONFIG_PROC_FS */ if (!ic_enable) return 0; pr_debug("IP-Config: Entered.\n"); #ifdef IPCONFIG_DYNAMIC try_try_again: #endif /* Wait for devices to appear */ err = wait_for_devices(); if (err) return err; /* Setup all network devices */ err = ic_open_devs(); if (err) return err; /* Give drivers a chance to settle */ msleep(CONF_POST_OPEN); /* * If the config information is insufficient (e.g., our IP address or * IP address of the boot server is missing or we have multiple network * interfaces and no default was set), use BOOTP or RARP to get the * missing values. */ if (ic_myaddr == NONE || #if defined(CONFIG_ROOT_NFS) || defined(CONFIG_CIFS_ROOT) (root_server_addr == NONE && ic_servaddr == NONE && (ROOT_DEV == Root_NFS || ROOT_DEV == Root_CIFS)) || #endif ic_first_dev->next) { #ifdef IPCONFIG_DYNAMIC if (ic_dynamic() < 0) { ic_close_devs(); /* * I don't know why, but sometimes the * eepro100 driver (at least) gets upset and * doesn't work the first time it's opened. * But then if you close it and reopen it, it * works just fine. So we need to try that at * least once before giving up. * * Also, if the root will be NFS-mounted, we * have nowhere to go if DHCP fails. So we * just have to keep trying forever. * * -- Chip */ #ifdef CONFIG_ROOT_NFS if (ROOT_DEV == Root_NFS) { pr_err("IP-Config: Retrying forever (NFS root)...\n"); goto try_try_again; } #endif #ifdef CONFIG_CIFS_ROOT if (ROOT_DEV == Root_CIFS) { pr_err("IP-Config: Retrying forever (CIFS root)...\n"); goto try_try_again; } #endif if (--retries) { pr_err("IP-Config: Reopening network devices...\n"); goto try_try_again; } /* Oh, well. At least we tried. */ pr_err("IP-Config: Auto-configuration of network failed\n"); return -1; } #else /* !DYNAMIC */ pr_err("IP-Config: Incomplete network configuration information\n"); ic_close_devs(); return -1; #endif /* IPCONFIG_DYNAMIC */ } else { /* Device selected manually or only one device -> use it */ ic_dev = ic_first_dev; } addr = root_nfs_parse_addr(root_server_path); if (root_server_addr == NONE) root_server_addr = addr; /* * Use defaults wherever applicable. */ if (ic_defaults() < 0) return -1; /* * Record which protocol was actually used. */ #ifdef IPCONFIG_DYNAMIC ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP); #endif #ifndef IPCONFIG_SILENT /* * Clue in the operator. */ pr_info("IP-Config: Complete:\n"); pr_info(" device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n", ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr, &ic_myaddr, &ic_netmask, &ic_gateway); pr_info(" host=%s, domain=%s, nis-domain=%s\n", utsname()->nodename, ic_domain, utsname()->domainname); pr_info(" bootserver=%pI4, rootserver=%pI4, rootpath=%s", &ic_servaddr, &root_server_addr, root_server_path); if (ic_dev_mtu) pr_cont(", mtu=%d", ic_dev_mtu); /* Name servers (if any): */ for (i = 0, count = 0; i < CONF_NAMESERVERS_MAX; i++) { if (ic_nameservers[i] != NONE) { if (i == 0) pr_info(" nameserver%u=%pI4", i, &ic_nameservers[i]); else pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]); count++; } if ((i + 1 == CONF_NAMESERVERS_MAX) && count > 0) pr_cont("\n"); } /* NTP servers (if any): */ for (i = 0, count = 0; i < CONF_NTP_SERVERS_MAX; i++) { if (ic_ntp_servers[i] != NONE) { if (i == 0) pr_info(" ntpserver%u=%pI4", i, &ic_ntp_servers[i]); else pr_cont(", ntpserver%u=%pI4", i, &ic_ntp_servers[i]); count++; } if ((i + 1 == CONF_NTP_SERVERS_MAX) && count > 0) pr_cont("\n"); } #endif /* !SILENT */ /* * Close all network devices except the device we've * autoconfigured and set up routes. */ if (ic_setup_if() < 0 || ic_setup_routes() < 0) err = -1; else err = 0; ic_close_devs(); return err; } late_initcall(ip_auto_config); /* * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel * command line parameter. See Documentation/admin-guide/nfs/nfsroot.rst. */ static int __init ic_proto_name(char *name) { if (!strcmp(name, "on") || !strcmp(name, "any")) { return 1; } if (!strcmp(name, "off") || !strcmp(name, "none")) { return 0; } #ifdef CONFIG_IP_PNP_DHCP else if (!strncmp(name, "dhcp", 4)) { char *client_id; ic_proto_enabled &= ~IC_RARP; client_id = strstr(name, "dhcp,"); if (client_id) { char *v; client_id = client_id + 5; v = strchr(client_id, ','); if (!v) return 1; *v = 0; if (kstrtou8(client_id, 0, dhcp_client_identifier)) pr_debug("DHCP: Invalid client identifier type\n"); strncpy(dhcp_client_identifier + 1, v + 1, 251); *v = ','; } return 1; } #endif #ifdef CONFIG_IP_PNP_BOOTP else if (!strcmp(name, "bootp")) { ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP); return 1; } #endif #ifdef CONFIG_IP_PNP_RARP else if (!strcmp(name, "rarp")) { ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP); return 1; } #endif #ifdef IPCONFIG_DYNAMIC else if (!strcmp(name, "both")) { ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */ return 1; } #endif return 0; } static int __init ip_auto_config_setup(char *addrs) { char *cp, *ip, *dp; int num = 0; ic_set_manually = 1; ic_enable = 1; /* * If any dhcp, bootp etc options are set, leave autoconfig on * and skip the below static IP processing. */ if (ic_proto_name(addrs)) return 1; /* If no static IP is given, turn off autoconfig and bail. */ if (*addrs == 0 || strcmp(addrs, "off") == 0 || strcmp(addrs, "none") == 0) { ic_enable = 0; return 1; } /* Initialise all name servers and NTP servers to NONE */ ic_nameservers_predef(); ic_ntp_servers_predef(); /* Parse string for static IP assignment. */ ip = addrs; while (ip && *ip) { if ((cp = strchr(ip, ':'))) *cp++ = '\0'; if (strlen(ip) > 0) { pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip); switch (num) { case 0: if ((ic_myaddr = in_aton(ip)) == ANY) ic_myaddr = NONE; break; case 1: if ((ic_servaddr = in_aton(ip)) == ANY) ic_servaddr = NONE; break; case 2: if ((ic_gateway = in_aton(ip)) == ANY) ic_gateway = NONE; break; case 3: if ((ic_netmask = in_aton(ip)) == ANY) ic_netmask = NONE; break; case 4: if ((dp = strchr(ip, '.'))) { *dp++ = '\0'; strscpy(utsname()->domainname, dp, sizeof(utsname()->domainname)); } strscpy(utsname()->nodename, ip, sizeof(utsname()->nodename)); ic_host_name_set = 1; break; case 5: strscpy(user_dev_name, ip, sizeof(user_dev_name)); break; case 6: if (ic_proto_name(ip) == 0 && ic_myaddr == NONE) { ic_enable = 0; } break; case 7: if (CONF_NAMESERVERS_MAX >= 1) { ic_nameservers[0] = in_aton(ip); if (ic_nameservers[0] == ANY) ic_nameservers[0] = NONE; } break; case 8: if (CONF_NAMESERVERS_MAX >= 2) { ic_nameservers[1] = in_aton(ip); if (ic_nameservers[1] == ANY) ic_nameservers[1] = NONE; } break; case 9: if (CONF_NTP_SERVERS_MAX >= 1) { ic_ntp_servers[0] = in_aton(ip); if (ic_ntp_servers[0] == ANY) ic_ntp_servers[0] = NONE; } break; } } ip = cp; num++; } return 1; } __setup("ip=", ip_auto_config_setup); static int __init nfsaddrs_config_setup(char *addrs) { return ip_auto_config_setup(addrs); } __setup("nfsaddrs=", nfsaddrs_config_setup); static int __init vendor_class_identifier_setup(char *addrs) { if (strscpy(vendor_class_identifier, addrs, sizeof(vendor_class_identifier)) >= sizeof(vendor_class_identifier)) pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n", vendor_class_identifier); return 1; } __setup("dhcpclass=", vendor_class_identifier_setup); static int __init set_carrier_timeout(char *str) { ssize_t ret; if (!str) return 0; ret = kstrtouint(str, 0, &carrier_timeout); if (ret) return 0; return 1; } __setup("carrier_timeout=", set_carrier_timeout);
linux-master
net/ipv4/ipconfig.c
// SPDX-License-Identifier: GPL-2.0-or-later /* * Linux NET3: IP/IP protocol decoder modified to support * virtual tunnel interface * * Authors: * Saurabh Mohan ([email protected]) 05/07/2012 */ /* This version of net/ipv4/ip_vti.c is cloned of net/ipv4/ipip.c For comments look at net/ipv4/ip_gre.c --ANK */ #include <linux/capability.h> #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/uaccess.h> #include <linux/skbuff.h> #include <linux/netdevice.h> #include <linux/in.h> #include <linux/tcp.h> #include <linux/udp.h> #include <linux/if_arp.h> #include <linux/init.h> #include <linux/netfilter_ipv4.h> #include <linux/if_ether.h> #include <linux/icmpv6.h> #include <net/sock.h> #include <net/ip.h> #include <net/icmp.h> #include <net/ip_tunnels.h> #include <net/inet_ecn.h> #include <net/xfrm.h> #include <net/net_namespace.h> #include <net/netns/generic.h> static struct rtnl_link_ops vti_link_ops __read_mostly; static unsigned int vti_net_id __read_mostly; static int vti_tunnel_init(struct net_device *dev); static int vti_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type, bool update_skb_dev) { struct ip_tunnel *tunnel; const struct iphdr *iph = ip_hdr(skb); struct net *net = dev_net(skb->dev); struct ip_tunnel_net *itn = net_generic(net, vti_net_id); tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY, iph->saddr, iph->daddr, 0); if (tunnel) { if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) goto drop; XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = tunnel; if (update_skb_dev) skb->dev = tunnel->dev; return xfrm_input(skb, nexthdr, spi, encap_type); } return -EINVAL; drop: kfree_skb(skb); return 0; } static int vti_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) { return vti_input(skb, nexthdr, spi, encap_type, false); } static int vti_rcv(struct sk_buff *skb, __be32 spi, bool update_skb_dev) { XFRM_SPI_SKB_CB(skb)->family = AF_INET; XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); return vti_input(skb, ip_hdr(skb)->protocol, spi, 0, update_skb_dev); } static int vti_rcv_proto(struct sk_buff *skb) { return vti_rcv(skb, 0, false); } static int vti_rcv_cb(struct sk_buff *skb, int err) { unsigned short family; struct net_device *dev; struct xfrm_state *x; const struct xfrm_mode *inner_mode; struct ip_tunnel *tunnel = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4; u32 orig_mark = skb->mark; int ret; if (!tunnel) return 1; dev = tunnel->dev; if (err) { DEV_STATS_INC(dev, rx_errors); DEV_STATS_INC(dev, rx_dropped); return 0; } x = xfrm_input_state(skb); inner_mode = &x->inner_mode; if (x->sel.family == AF_UNSPEC) { inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); if (inner_mode == NULL) { XFRM_INC_STATS(dev_net(skb->dev), LINUX_MIB_XFRMINSTATEMODEERROR); return -EINVAL; } } family = inner_mode->family; skb->mark = be32_to_cpu(tunnel->parms.i_key); ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family); skb->mark = orig_mark; if (!ret) return -EPERM; skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(skb->dev))); skb->dev = dev; dev_sw_netstats_rx_add(dev, skb->len); return 0; } static bool vti_state_check(const struct xfrm_state *x, __be32 dst, __be32 src) { xfrm_address_t *daddr = (xfrm_address_t *)&dst; xfrm_address_t *saddr = (xfrm_address_t *)&src; /* if there is no transform then this tunnel is not functional. * Or if the xfrm is not mode tunnel. */ if (!x || x->props.mode != XFRM_MODE_TUNNEL || x->props.family != AF_INET) return false; if (!dst) return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET); if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET)) return false; return true; } static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) { struct ip_tunnel *tunnel = netdev_priv(dev); struct ip_tunnel_parm *parms = &tunnel->parms; struct dst_entry *dst = skb_dst(skb); struct net_device *tdev; /* Device to other host */ int pkt_len = skb->len; int err; int mtu; if (!dst) { switch (skb->protocol) { case htons(ETH_P_IP): { struct rtable *rt; fl->u.ip4.flowi4_oif = dev->ifindex; fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC; rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4); if (IS_ERR(rt)) { DEV_STATS_INC(dev, tx_carrier_errors); goto tx_error_icmp; } dst = &rt->dst; skb_dst_set(skb, dst); break; } #if IS_ENABLED(CONFIG_IPV6) case htons(ETH_P_IPV6): fl->u.ip6.flowi6_oif = dev->ifindex; fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC; dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6); if (dst->error) { dst_release(dst); dst = NULL; DEV_STATS_INC(dev, tx_carrier_errors); goto tx_error_icmp; } skb_dst_set(skb, dst); break; #endif default: DEV_STATS_INC(dev, tx_carrier_errors); goto tx_error_icmp; } } dst_hold(dst); dst = xfrm_lookup_route(tunnel->net, dst, fl, NULL, 0); if (IS_ERR(dst)) { DEV_STATS_INC(dev, tx_carrier_errors); goto tx_error_icmp; } if (dst->flags & DST_XFRM_QUEUE) goto xmit; if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) { DEV_STATS_INC(dev, tx_carrier_errors); dst_release(dst); goto tx_error_icmp; } tdev = dst->dev; if (tdev == dev) { dst_release(dst); DEV_STATS_INC(dev, collisions); goto tx_error; } mtu = dst_mtu(dst); if (skb->len > mtu) { skb_dst_update_pmtu_no_confirm(skb, mtu); if (skb->protocol == htons(ETH_P_IP)) { if (!(ip_hdr(skb)->frag_off & htons(IP_DF))) goto xmit; icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); } else { if (mtu < IPV6_MIN_MTU) mtu = IPV6_MIN_MTU; icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); } dst_release(dst); goto tx_error; } xmit: skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); skb_dst_set(skb, dst); skb->dev = skb_dst(skb)->dev; err = dst_output(tunnel->net, skb->sk, skb); if (net_xmit_eval(err) == 0) err = pkt_len; iptunnel_xmit_stats(dev, err); return NETDEV_TX_OK; tx_error_icmp: dst_link_failure(skb); tx_error: DEV_STATS_INC(dev, tx_errors); kfree_skb(skb); return NETDEV_TX_OK; } /* This function assumes it is being called from dev_queue_xmit() * and that skb is filled properly by that function. */ static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); struct flowi fl; if (!pskb_inet_may_pull(skb)) goto tx_err; memset(&fl, 0, sizeof(fl)); switch (skb->protocol) { case htons(ETH_P_IP): memset(IPCB(skb), 0, sizeof(*IPCB(skb))); xfrm_decode_session(skb, &fl, AF_INET); break; case htons(ETH_P_IPV6): memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); xfrm_decode_session(skb, &fl, AF_INET6); break; default: goto tx_err; } /* override mark with tunnel output key */ fl.flowi_mark = be32_to_cpu(tunnel->parms.o_key); return vti_xmit(skb, dev, &fl); tx_err: DEV_STATS_INC(dev, tx_errors); kfree_skb(skb); return NETDEV_TX_OK; } static int vti4_err(struct sk_buff *skb, u32 info) { __be32 spi; __u32 mark; struct xfrm_state *x; struct ip_tunnel *tunnel; struct ip_esp_hdr *esph; struct ip_auth_hdr *ah ; struct ip_comp_hdr *ipch; struct net *net = dev_net(skb->dev); const struct iphdr *iph = (const struct iphdr *)skb->data; int protocol = iph->protocol; struct ip_tunnel_net *itn = net_generic(net, vti_net_id); tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY, iph->daddr, iph->saddr, 0); if (!tunnel) return -1; mark = be32_to_cpu(tunnel->parms.o_key); switch (protocol) { case IPPROTO_ESP: esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); spi = esph->spi; break; case IPPROTO_AH: ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); spi = ah->spi; break; case IPPROTO_COMP: ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2)); spi = htonl(ntohs(ipch->cpi)); break; default: return 0; } switch (icmp_hdr(skb)->type) { case ICMP_DEST_UNREACH: if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) return 0; break; case ICMP_REDIRECT: break; default: return 0; } x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr, spi, protocol, AF_INET); if (!x) return 0; if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) ipv4_update_pmtu(skb, net, info, 0, protocol); else ipv4_redirect(skb, net, 0, protocol); xfrm_state_put(x); return 0; } static int vti_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) { int err = 0; if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { if (p->iph.version != 4 || p->iph.protocol != IPPROTO_IPIP || p->iph.ihl != 5) return -EINVAL; } if (!(p->i_flags & GRE_KEY)) p->i_key = 0; if (!(p->o_flags & GRE_KEY)) p->o_key = 0; p->i_flags = VTI_ISVTI; err = ip_tunnel_ctl(dev, p, cmd); if (err) return err; if (cmd != SIOCDELTUNNEL) { p->i_flags |= GRE_KEY; p->o_flags |= GRE_KEY; } return 0; } static const struct net_device_ops vti_netdev_ops = { .ndo_init = vti_tunnel_init, .ndo_uninit = ip_tunnel_uninit, .ndo_start_xmit = vti_tunnel_xmit, .ndo_siocdevprivate = ip_tunnel_siocdevprivate, .ndo_change_mtu = ip_tunnel_change_mtu, .ndo_get_stats64 = dev_get_tstats64, .ndo_get_iflink = ip_tunnel_get_iflink, .ndo_tunnel_ctl = vti_tunnel_ctl, }; static void vti_tunnel_setup(struct net_device *dev) { dev->netdev_ops = &vti_netdev_ops; dev->header_ops = &ip_tunnel_header_ops; dev->type = ARPHRD_TUNNEL; ip_tunnel_setup(dev, vti_net_id); } static int vti_tunnel_init(struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); struct iphdr *iph = &tunnel->parms.iph; __dev_addr_set(dev, &iph->saddr, 4); memcpy(dev->broadcast, &iph->daddr, 4); dev->flags = IFF_NOARP; dev->addr_len = 4; dev->features |= NETIF_F_LLTX; netif_keep_dst(dev); return ip_tunnel_init(dev); } static void __net_init vti_fb_tunnel_init(struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); struct iphdr *iph = &tunnel->parms.iph; iph->version = 4; iph->protocol = IPPROTO_IPIP; iph->ihl = 5; } static struct xfrm4_protocol vti_esp4_protocol __read_mostly = { .handler = vti_rcv_proto, .input_handler = vti_input_proto, .cb_handler = vti_rcv_cb, .err_handler = vti4_err, .priority = 100, }; static struct xfrm4_protocol vti_ah4_protocol __read_mostly = { .handler = vti_rcv_proto, .input_handler = vti_input_proto, .cb_handler = vti_rcv_cb, .err_handler = vti4_err, .priority = 100, }; static struct xfrm4_protocol vti_ipcomp4_protocol __read_mostly = { .handler = vti_rcv_proto, .input_handler = vti_input_proto, .cb_handler = vti_rcv_cb, .err_handler = vti4_err, .priority = 100, }; #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) static int vti_rcv_tunnel(struct sk_buff *skb) { XFRM_SPI_SKB_CB(skb)->family = AF_INET; XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); return vti_input(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr, 0, false); } static struct xfrm_tunnel vti_ipip_handler __read_mostly = { .handler = vti_rcv_tunnel, .cb_handler = vti_rcv_cb, .err_handler = vti4_err, .priority = 0, }; #if IS_ENABLED(CONFIG_IPV6) static struct xfrm_tunnel vti_ipip6_handler __read_mostly = { .handler = vti_rcv_tunnel, .cb_handler = vti_rcv_cb, .err_handler = vti4_err, .priority = 0, }; #endif #endif static int __net_init vti_init_net(struct net *net) { int err; struct ip_tunnel_net *itn; err = ip_tunnel_init_net(net, vti_net_id, &vti_link_ops, "ip_vti0"); if (err) return err; itn = net_generic(net, vti_net_id); if (itn->fb_tunnel_dev) vti_fb_tunnel_init(itn->fb_tunnel_dev); return 0; } static void __net_exit vti_exit_batch_net(struct list_head *list_net) { ip_tunnel_delete_nets(list_net, vti_net_id, &vti_link_ops); } static struct pernet_operations vti_net_ops = { .init = vti_init_net, .exit_batch = vti_exit_batch_net, .id = &vti_net_id, .size = sizeof(struct ip_tunnel_net), }; static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { return 0; } static void vti_netlink_parms(struct nlattr *data[], struct ip_tunnel_parm *parms, __u32 *fwmark) { memset(parms, 0, sizeof(*parms)); parms->iph.protocol = IPPROTO_IPIP; if (!data) return; parms->i_flags = VTI_ISVTI; if (data[IFLA_VTI_LINK]) parms->link = nla_get_u32(data[IFLA_VTI_LINK]); if (data[IFLA_VTI_IKEY]) parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]); if (data[IFLA_VTI_OKEY]) parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]); if (data[IFLA_VTI_LOCAL]) parms->iph.saddr = nla_get_in_addr(data[IFLA_VTI_LOCAL]); if (data[IFLA_VTI_REMOTE]) parms->iph.daddr = nla_get_in_addr(data[IFLA_VTI_REMOTE]); if (data[IFLA_VTI_FWMARK]) *fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]); } static int vti_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { struct ip_tunnel_parm parms; __u32 fwmark = 0; vti_netlink_parms(data, &parms, &fwmark); return ip_tunnel_newlink(dev, tb, &parms, fwmark); } static int vti_changelink(struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { struct ip_tunnel *t = netdev_priv(dev); __u32 fwmark = t->fwmark; struct ip_tunnel_parm p; vti_netlink_parms(data, &p, &fwmark); return ip_tunnel_changelink(dev, tb, &p, fwmark); } static size_t vti_get_size(const struct net_device *dev) { return /* IFLA_VTI_LINK */ nla_total_size(4) + /* IFLA_VTI_IKEY */ nla_total_size(4) + /* IFLA_VTI_OKEY */ nla_total_size(4) + /* IFLA_VTI_LOCAL */ nla_total_size(4) + /* IFLA_VTI_REMOTE */ nla_total_size(4) + /* IFLA_VTI_FWMARK */ nla_total_size(4) + 0; } static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev) { struct ip_tunnel *t = netdev_priv(dev); struct ip_tunnel_parm *p = &t->parms; if (nla_put_u32(skb, IFLA_VTI_LINK, p->link) || nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key) || nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key) || nla_put_in_addr(skb, IFLA_VTI_LOCAL, p->iph.saddr) || nla_put_in_addr(skb, IFLA_VTI_REMOTE, p->iph.daddr) || nla_put_u32(skb, IFLA_VTI_FWMARK, t->fwmark)) return -EMSGSIZE; return 0; } static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = { [IFLA_VTI_LINK] = { .type = NLA_U32 }, [IFLA_VTI_IKEY] = { .type = NLA_U32 }, [IFLA_VTI_OKEY] = { .type = NLA_U32 }, [IFLA_VTI_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) }, [IFLA_VTI_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) }, [IFLA_VTI_FWMARK] = { .type = NLA_U32 }, }; static struct rtnl_link_ops vti_link_ops __read_mostly = { .kind = "vti", .maxtype = IFLA_VTI_MAX, .policy = vti_policy, .priv_size = sizeof(struct ip_tunnel), .setup = vti_tunnel_setup, .validate = vti_tunnel_validate, .newlink = vti_newlink, .changelink = vti_changelink, .dellink = ip_tunnel_dellink, .get_size = vti_get_size, .fill_info = vti_fill_info, .get_link_net = ip_tunnel_get_link_net, }; static int __init vti_init(void) { const char *msg; int err; pr_info("IPv4 over IPsec tunneling driver\n"); msg = "tunnel device"; err = register_pernet_device(&vti_net_ops); if (err < 0) goto pernet_dev_failed; msg = "tunnel protocols"; err = xfrm4_protocol_register(&vti_esp4_protocol, IPPROTO_ESP); if (err < 0) goto xfrm_proto_esp_failed; err = xfrm4_protocol_register(&vti_ah4_protocol, IPPROTO_AH); if (err < 0) goto xfrm_proto_ah_failed; err = xfrm4_protocol_register(&vti_ipcomp4_protocol, IPPROTO_COMP); if (err < 0) goto xfrm_proto_comp_failed; #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) msg = "ipip tunnel"; err = xfrm4_tunnel_register(&vti_ipip_handler, AF_INET); if (err < 0) goto xfrm_tunnel_ipip_failed; #if IS_ENABLED(CONFIG_IPV6) err = xfrm4_tunnel_register(&vti_ipip6_handler, AF_INET6); if (err < 0) goto xfrm_tunnel_ipip6_failed; #endif #endif msg = "netlink interface"; err = rtnl_link_register(&vti_link_ops); if (err < 0) goto rtnl_link_failed; return err; rtnl_link_failed: #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) #if IS_ENABLED(CONFIG_IPV6) xfrm4_tunnel_deregister(&vti_ipip6_handler, AF_INET6); xfrm_tunnel_ipip6_failed: #endif xfrm4_tunnel_deregister(&vti_ipip_handler, AF_INET); xfrm_tunnel_ipip_failed: #endif xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP); xfrm_proto_comp_failed: xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH); xfrm_proto_ah_failed: xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP); xfrm_proto_esp_failed: unregister_pernet_device(&vti_net_ops); pernet_dev_failed: pr_err("vti init: failed to register %s\n", msg); return err; } static void __exit vti_fini(void) { rtnl_link_unregister(&vti_link_ops); #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) #if IS_ENABLED(CONFIG_IPV6) xfrm4_tunnel_deregister(&vti_ipip6_handler, AF_INET6); #endif xfrm4_tunnel_deregister(&vti_ipip_handler, AF_INET); #endif xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP); xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH); xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP); unregister_pernet_device(&vti_net_ops); } module_init(vti_init); module_exit(vti_fini); MODULE_LICENSE("GPL"); MODULE_ALIAS_RTNL_LINK("vti"); MODULE_ALIAS_NETDEV("ip_vti0");
linux-master
net/ipv4/ip_vti.c