Code for How to Build a Password Manager in Python Tutorial

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password_manager.py

import json, hashlib, getpass, os, pyperclip, sys from cryptography.fernet import Fernet # Function for Hashing the Master Password. def hash_password(password): sha256 = hashlib.sha256() sha256.update(password.encode()) return sha256.hexdigest() # Generate a secret key. This should be done only once as you'll see. def generate_key(): return Fernet.generate_key() # Initialize Fernet cipher with the provided key. def initialize_cipher(key): return Fernet(key) # Function to encrypt a password. def encrypt_password(cipher, password): return cipher.encrypt(password.encode()).decode() # Function to decrypt a password. def decrypt_password(cipher, encrypted_password): return cipher.decrypt(encrypted_password.encode()).decode() # Function to register you. def register(username, master_password): # Encrypt the master password before storing it hashed_master_password = hash_password(master_password) user_data = {'username': username, 'master_password': hashed_master_password} file_name = 'user_data.json' if os.path.exists(file_name) and os.path.getsize(file_name) == 0: with open(file_name, 'w') as file: json.dump(user_data, file) print("\n[+] Registration complete!!\n") else: with open(file_name, 'x') as file: json.dump(user_data, file) print("\n[+] Registration complete!!\n") # Function to log you in. def login(username, entered_password): try: with open('user_data.json', 'r') as file: user_data = json.load(file) stored_password_hash = user_data.get('master_password') entered_password_hash = hash_password(entered_password) if entered_password_hash == stored_password_hash and username == user_data.get('username'): print("\n[+] Login Successful..\n") else: print("\n[-] Invalid Login credentials. Please use the credentials you used to register.\n") sys.exit() except Exception: print("\n[-] You have not registered. Please do that.\n") sys.exit() # Function to view saved websites. def view_websites(): try: with open('passwords.json', 'r') as data: view = json.load(data) print("\nWebsites you saved...\n") for x in view: print(x['website']) print('\n') except FileNotFoundError: print("\n[-] You have not saved any passwords!\n") # Load or generate the encryption key. key_filename = 'encryption_key.key' if os.path.exists(key_filename): with open(key_filename, 'rb') as key_file: key = key_file.read() else: key = generate_key() with open(key_filename, 'wb') as key_file: key_file.write(key) cipher = initialize_cipher(key) # Function to add (save password). def add_password(website, password): # Check if passwords.json exists if not os.path.exists('passwords.json'): # If passwords.json doesn't exist, initialize it with an empty list data = [] else: # Load existing data from passwords.json try: with open('passwords.json', 'r') as file: data = json.load(file) except json.JSONDecodeError: # Handle the case where passwords.json is empty or invalid JSON. data = [] # Encrypt the password encrypted_password = encrypt_password(cipher, password) # Create a dictionary to store the website and password password_entry = {'website': website, 'password': encrypted_password} data.append(password_entry) # Save the updated list back to passwords.json with open('passwords.json', 'w') as file: json.dump(data, file, indent=4) # Function to retrieve a saved password. def get_password(website): # Check if passwords.json exists if not os.path.exists('passwords.json'): return None # Load existing data from passwords.json try: with open('passwords.json', 'r') as file: data = json.load(file) except json.JSONDecodeError: data = [] # Loop through all the websites and check if the requested website exists. for entry in data: if entry['website'] == website: # Decrypt and return the password decrypted_password = decrypt_password(cipher, entry['password']) return decrypted_password return None # Infinite loop to keep the program running until the user chooses to quit. while True: print("1. Register") print("2. Login") print("3. Quit") choice = input("Enter your choice: ") if choice == '1': # If a user wants to register file = 'user_data.json' if os.path.exists(file) and os.path.getsize(file) != 0: print("\n[-] Master user already exists!!") sys.exit() else: username = input("Enter your username: ") master_password = getpass.getpass("Enter your master password: ") register(username, master_password) elif choice == '2': # If a User wants to log in file = 'user_data.json' if os.path.exists(file): username = input("Enter your username: ") master_password = getpass.getpass("Enter your master password: ") login(username, master_password) else: print("\n[-] You have not registered. Please do that.\n") sys.exit() # Various options after a successful Login. while True: print("1. Add Password") print("2. Get Password") print("3. View Saved websites") print("4. Quit") password_choice = input("Enter your choice: ") if password_choice == '1': # If a user wants to add a password website = input("Enter website: ") password = getpass.getpass("Enter password: ") # Encrypt and add the password add_password(website, password) print("\n[+] Password added!\n") elif password_choice == '2': # If a User wants to retrieve a password website = input("Enter website: ") decrypted_password = get_password(website) if website and decrypted_password: # Copy password to clipboard for convenience pyperclip.copy(decrypted_password) print(f"\n[+] Password for {website}: {decrypted_password}\n[+] Password copied to clipboard.\n") else: print("\n[-] Password not found! Did you save the password?" "\n[-] Use option 3 to see the websites you saved.\n") elif password_choice == '3': # If a user wants to view saved websites view_websites() elif password_choice == '4': # If a user wants to quit the password manager break elif choice == '3': # If a user wants to quit the program break