gistfile1.py

### Password hashing

def hash_pwd(pwd, salt=None, rounds=2**16):
    """Hashes a password using 2**16 rounds of SHA512 and a 64-bit salt.
       The salt and hash result are concatenated and returned as a hexdigest.
    """
    # Note: if this turns out to be too slow, consider using the py-bcrypt package
    if salt is None:
        # Note: Do not use python's random module for crypto!
        salt = os.urandom(8)
    else:
        salt = salt[:16].decode('hex')
    h = hashlib.sha512()
    while rounds > 0:
        h.update(salt)
        h.update(pwd)
        rounds -= 1
    return salt.encode('hex') + h.hexdigest()

def verify_pwd(pwd, hashed):
    return hash_pwd(pwd, hashed) == hashed