Secure LAN Tool Passwords

TL;DR

Don’t store passwords in plain text! Use a password manager with a strong master key, or integrate your tool with an existing authentication system like Active Directory. If you *must* store them locally, encrypt them using a robust algorithm and securely manage the encryption key.

Storing LAN Tool Passwords Securely

1. Understand the Risks: Storing passwords anywhere is risky. Plain text storage is extremely dangerous – anyone with access to the file can see all your credentials. Even seemingly secure methods can be vulnerable if not implemented correctly.
   • Compromised LAN = Compromised Passwords
   • Insider Threats
   • Weak Encryption
2. Option 1: Password Manager (Recommended)

   The best approach is to use a dedicated password manager. This centralises storage and provides strong encryption.

   • Bitwarden, LastPass, KeePass: These are popular options. Choose one that suits your needs and budget.
   • Strong Master Key: The security of the entire system relies on a very strong master key. Use a long, complex password or passphrase.
   • Multi-Factor Authentication (MFA): Enable MFA wherever possible for added protection.
3. Option 2: Integrate with Existing Authentication (Highly Recommended)

   If your organisation uses an authentication system like Active Directory, integrate your LAN tool with it.

   • Centralised Management: Users use their existing credentials.
   • Policy Enforcement: Password complexity and rotation policies are handled centrally.
   • Auditing: Easier to track access and changes.
   • Example (Python with LDAP):

     import ldap
     
     try:
         l = ldap.initialize('ldap://your_ldap_server')
         l.simple_bind_s(username, password)
         # Authentication successful
     except ldap.LDAPError as e:
         print(f'Authentication failed: {e}')

4. Option 3: Local Encryption (If absolutely necessary)

   Only use this if you cannot use a password manager or integrate with an existing system. It’s more complex and requires careful implementation.

   • Choose a Strong Algorithm: AES-256 is a good choice.

     from cryptography.fernet import Fernet
     
     key = Fernet.generate_key()
     f = Fernet(key)
     token = f.encrypt(b'my secret password')
     decrypted_password = f.decrypt(token).decode()

   • Secure Key Storage: This is the hardest part! Do not store the key with the encrypted passwords. Consider:
     • Hardware Security Module (HSM)
     • Key Management System (KMS)
     • Separate, offline storage (very carefully managed).
   • Salt and Hash: Before encrypting, hash the password with a unique salt for each user. This adds an extra layer of security.

     import hashlib
     salt = 'your_unique_salt'
     hashed_password = hashlib.sha256((password + salt).encode()).hexdigest()

   • Regular Key Rotation: Change the encryption key periodically.
5. Avoid These Mistakes:
   • Storing passwords in plain text files (e.g., CSV, TXT).
   • Using weak encryption algorithms (e.g., DES, RC4).
   • Hardcoding keys into your application code.
   • Sharing the encryption key with anyone who doesn’t absolutely need it.