adilaijaz10/secure_data_encryption_assignment

1import streamlit as st2import hashlib3import base644import uuid5from cryptography.fernet import Fernet6from cryptography.hazmat.primitives import hashes7from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC8 9# Initialize session state for failed attempts and login status10if 'failed_attempts' not in st.session_state:11    st.session_state.failed_attempts = 012if 'is_authenticated' not in st.session_state:13    st.session_state.is_authenticated = True14if 'stored_data' not in st.session_state:15    st.session_state.stored_data = {}  # {"id": {"encrypted_text": "xyz", "passkey_hash": "hashed", "salt": "salt"}}16 17# Function to derive encryption key from passkey18def get_key_from_passkey(passkey, salt=None):19    if salt is None:20        salt = uuid.uuid4().hex.encode()21    kdf = PBKDF2HMAC(22        algorithm=hashes.SHA256(),23        length=32,24        salt=salt if isinstance(salt, bytes) else salt.encode(),25        iterations=100000,26    )27    key = base64.urlsafe_b64encode(kdf.derive(passkey.encode()))28    return key, salt29 30# Function to hash passkey31def hash_passkey(passkey):32    return hashlib.sha256(passkey.encode()).hexdigest()33 34# Function to encrypt data35def encrypt_data(text, passkey):36    key, salt = get_key_from_passkey(passkey)37    cipher = Fernet(key)38    encrypted_text = cipher.encrypt(text.encode()).decode()39    return encrypted_text, salt40 41# Function to decrypt data42def decrypt_data(data_id, encrypted_text, passkey):43    if data_id not in st.session_state.stored_data:44        st.session_state.failed_attempts += 145        return None46    47    data_info = st.session_state.stored_data[data_id]48    salt = data_info["salt"]49    stored_passkey_hash = data_info["passkey_hash"]50    51    # Check if passkey is correct52    if hash_passkey(passkey) != stored_passkey_hash:53        st.session_state.failed_attempts += 154        return None55    56    # Derive key and decrypt57    key, _ = get_key_from_passkey(passkey, salt)58    cipher = Fernet(key)59    try:60        decrypted_text = cipher.decrypt(encrypted_text.encode()).decode()61        st.session_state.failed_attempts = 062        return decrypted_text63    except Exception:64        st.session_state.failed_attempts += 165        return None66 67# Function to reset attempts after successful login68def reset_attempts():69    st.session_state.failed_attempts = 070    st.session_state.is_authenticated = True71 72# Streamlit UI73st.title("🔒 Secure Data Encryption System")74 75# Check if too many failed attempts76if st.session_state.failed_attempts >= 3:77    st.session_state.is_authenticated = False78 79# Navigation80menu = ["Home", "Store Data", "Retrieve Data", "Login"]81choice = st.sidebar.selectbox("Navigation", menu)82 83if not st.session_state.is_authenticated and choice != "Login":84    st.warning("🔒 Too many failed attempts! Please login to continue.")85    choice = "Login"86 87if choice == "Home":88    st.subheader("🏠 Welcome to the Secure Data System")89    st.write("Use this app to **securely store and retrieve data** using unique passkeys.")90    st.info("Your data is encrypted with strong cryptography and can only be accessed with the correct passkey.")91    92    # Display stored data count93    st.subheader("📊 System Status")94    st.write(f"Number of encrypted entries: {len(st.session_state.stored_data)}")95 96elif choice == "Store Data":97    st.subheader("📂 Store Data Securely")98    user_data = st.text_area("Enter Data to Encrypt:")99    passkey = st.text_input("Create a Passkey:", type="password")100    confirm_passkey = st.text_input("Confirm Passkey:", type="password")101 102    if st.button("Encrypt & Save"):103        if user_data and passkey and confirm_passkey:104            if passkey != confirm_passkey:105                st.error("⚠️ Passkeys don't match!")106            else:107                # Generate a unique ID for this data108                data_id = uuid.uuid4().hex109                110                # Hash the passkey and encrypt the data111                passkey_hash = hash_passkey(passkey)112                encrypted_text, salt = encrypt_data(user_data, passkey)113                114                # Store the encrypted data with its metadata115                st.session_state.stored_data[data_id] = {116                    "encrypted_text": encrypted_text,117                    "passkey_hash": passkey_hash,118                    "salt": salt119                }120                121                st.success("✅ Data stored securely!")122                st.info(f"Your data ID is: **{data_id}**")123                st.warning("⚠️ Please save this ID. You will need it to retrieve your data.")124        else:125            st.error("⚠️ All fields are required!")126 127elif choice == "Retrieve Data":128    st.subheader("🔍 Retrieve Your Data")129    data_id = st.text_input("Enter Data ID:")130    passkey = st.text_input("Enter Passkey:", type="password")131    132    attempts_left = 3 - st.session_state.failed_attempts133    st.info(f"Attempts remaining: {attempts_left}")134 135    if st.button("Decrypt"):136        if data_id and passkey:137            if data_id in st.session_state.stored_data:138                encrypted_text = st.session_state.stored_data[data_id]["encrypted_text"]139                decrypted_text = decrypt_data(data_id, encrypted_text, passkey)140                141                if decrypted_text:142                    st.success("✅ Decryption successful!")143                    st.code(decrypted_text, language="text")144                else:145                    st.error(f"❌ Incorrect passkey! Attempts remaining: {3 - st.session_state.failed_attempts}")146                    147                    if st.session_state.failed_attempts >= 3:148                        st.warning("🔒 Too many failed attempts! Redirecting to Login Page.")149                        st.session_state.is_authenticated = False150                        st.experimental_rerun()151            else:152                st.error("❌ Data ID not found!")153        else:154            st.error("⚠️ Both fields are required!")155 156elif choice == "Login":157    st.subheader("🔑 Reauthorization Required")158    st.write("You have been locked out due to too many failed attempts.")159    login_pass = st.text_input("Enter Master Password:", type="password")160 161    if st.button("Login"):162        # In a real application, use a more secure master password or authentication system163        if login_pass == "admin123":  164            reset_attempts()165            st.success("✅ Reauthorized successfully! Redirecting...")166            st.experimental_rerun()167        else:168            st.error("❌ Incorrect password!")169