Create app.py

app.py

@@ -0,0 +1,184 @@
+# Initialize session state variables if they don't exist
+if 'failed_attempts' not in st.session_state:
+    st.session_state.failed_attempts = 0
+if 'stored_data' not in st.session_state:
+    st.session_state.stored_data = {}
+if 'current_page' not in st.session_state:
+    st.session_state.current_page = "Home"
+if 'last_attempt_time' not in st.session_state:
+    st.session_state.last_attempt_time = 0
+
+# Function to hash passkey
+def hash_passkey(passkey):
+    return hashlib.sha256(passkey.encode()).hexdigest()
+
+# Function to generate a key from passkey (for encryption)
+def generate_key_from_passkey(passkey):
+    # Use the passkey to create a consistent key
+    hashed = hashlib.sha256(passkey.encode()).digest()
+    # Ensure it's valid for Fernet (32 url-safe base64-encoded bytes)
+    return base64.urlsafe_b64encode(hashed[:32])
+
+# Function to encrypt data
+def encrypt_data(text, passkey):
+    key = generate_key_from_passkey(passkey)
+    cipher = Fernet(key)
+    return cipher.encrypt(text.encode()).decode()
+
+# Function to decrypt data
+def decrypt_data(encrypted_text, passkey, data_id):
+    try:
+        # Check if the passkey matches
+        hashed_passkey = hash_passkey(passkey)
+        if data_id in st.session_state.stored_data and st.session_state.stored_data[data_id]["passkey"] == hashed_passkey:
+            # If passkey matches, decrypt the data
+            key = generate_key_from_passkey(passkey)
+            cipher = Fernet(key)
+            decrypted = cipher.decrypt(encrypted_text.encode()).decode()
+            st.session_state.failed_attempts = 0
+            return decrypted
+        else:
+            # Increment failed attempts
+            st.session_state.failed_attempts += 1
+            st.session_state.last_attempt_time = time.time()
+            return None
+    except Exception as e:
+        # If decryption fails, increment failed attempts
+        st.session_state.failed_attempts += 1
+        st.session_state.last_attempt_time = time.time()
+        return None
+
+# Function to generate a unique ID for data
+def generate_data_id():
+    import uuid
+    return str(uuid.uuid4())
+
+# Function to reset failed attempts
+def reset_failed_attempts():
+    st.session_state.failed_attempts = 0
+
+# Function to change page
+def change_page(page):
+    st.session_state.current_page = page
+
+# Streamlit UI
+st.title("🔒 Secure Data Encryption System")
+
+# Navigation
+menu = ["Home", "Store Data", "Retrieve Data", "Login"]
+choice = st.sidebar.selectbox("Navigation", menu, index=menu.index(st.session_state.current_page))
+
+# Update current page based on selection
+st.session_state.current_page = choice
+
+# Check if too many failed attempts
+if st.session_state.failed_attempts >= 3:
+    # Force redirect to login page
+    st.session_state.current_page = "Login"
+    st.warning("🔒 Too many failed attempts! Reauthorization required.")
+
+# Display current page
+if st.session_state.current_page == "Home":
+    st.subheader("🏠 Welcome to the Secure Data System")
+    st.write("Use this app to **securely store and retrieve data** using unique passkeys.")
+    
+    col1, col2 = st.columns(2)
+    with col1:
+        if st.button("Store New Data", use_container_width=True):
+            change_page("Store Data")
+    with col2:
+        if st.button("Retrieve Data", use_container_width=True):
+            change_page("Retrieve Data")
+    
+    # Display stored data count
+    st.info(f"Currently storing {len(st.session_state.stored_data)} encrypted data entries.")
+
+elif st.session_state.current_page == "Store Data":
+    st.subheader("📂 Store Data Securely")
+    user_data = st.text_area("Enter Data:")
+    passkey = st.text_input("Enter Passkey:", type="password")
+    confirm_passkey = st.text_input("Confirm Passkey:", type="password")
+
+    if st.button("Encrypt & Save"):
+        if user_data and passkey and confirm_passkey:
+            if passkey != confirm_passkey:
+                st.error("⚠️ Passkeys do not match!")
+            else:
+                # Generate a unique ID for this data
+                data_id = generate_data_id()
+                
+                # Hash the passkey
+                hashed_passkey = hash_passkey(passkey)
+                
+                # Encrypt the data
+                encrypted_text = encrypt_data(user_data, passkey)
+                
+                # Store in the required format
+                st.session_state.stored_data[data_id] = {
+                    "encrypted_text": encrypted_text,
+                    "passkey": hashed_passkey
+                }
+                
+                st.success("✅ Data stored securely!")
+                
+                # Display the data ID for retrieval
+                st.code(data_id, language="text")
+                st.info("⚠️ Save this Data ID! You'll need it to retrieve your data.")
+        else:
+            st.error("⚠️ All fields are required!")
+
+elif st.session_state.current_page == "Retrieve Data":
+    st.subheader("🔍 Retrieve Your Data")
+    
+    # Show attempts remaining
+    attempts_remaining = 3 - st.session_state.failed_attempts
+    st.info(f"Attempts remaining: {attempts_remaining}")
+    
+    data_id = st.text_input("Enter Data ID:")
+    passkey = st.text_input("Enter Passkey:", type="password")
+
+    if st.button("Decrypt"):
+        if data_id and passkey:
+            if data_id in st.session_state.stored_data:
+                encrypted_text = st.session_state.stored_data[data_id]["encrypted_text"]
+                decrypted_text = decrypt_data(encrypted_text, passkey, data_id)
+
+                if decrypted_text:
+                    st.success("✅ Decryption successful!")
+                    st.markdown("### Your Decrypted Data:")
+                    st.code(decrypted_text, language="text")
+                else:
+                    st.error(f"❌ Incorrect passkey! Attempts remaining: {3 - st.session_state.failed_attempts}")
+            else:
+                st.error("❌ Data ID not found!")
+                
+            # Check if too many failed attempts after this attempt
+            if st.session_state.failed_attempts >= 3:
+                st.warning("🔒 Too many failed attempts! Redirecting to Login Page.")
+                st.session_state.current_page = "Login"
+                st.rerun()  # Updated from experimental_rerun()
+        else:
+            st.error("⚠️ Both fields are required!")
+
+elif st.session_state.current_page == "Login":
+    st.subheader("🔑 Reauthorization Required")
+    
+    # Add a simple timeout mechanism
+    if time.time() - st.session_state.last_attempt_time < 10 and st.session_state.failed_attempts >= 3:
+        remaining_time = int(10 - (time.time() - st.session_state.last_attempt_time))
+        st.warning(f"🕒 Please wait {remaining_time} seconds before trying again.")
+    else:
+        login_pass = st.text_input("Enter Master Password:", type="password")
+
+        if st.button("Login"):
+            if login_pass == "admin123":  # Hardcoded for demo, replace with proper auth
+                reset_failed_attempts()
+                st.success("✅ Reauthorized successfully!")
+                st.session_state.current_page = "Home"
+                st.rerun()  # Updated from experimental_rerun()
+            else:
+                st.error("❌ Incorrect password!")
+
+# Add a footer
+st.markdown("---")
+st.markdown("🔐 Secure Data Encryption System | Educational Project")