Files
password-security-python/argon2_algorithm.py

55 lines
1.6 KiB
Python

"""Argon2 algorithm implementation."""
from __future__ import annotations
import base64
import binascii
from argon2 import PasswordHasher
from argon2.exceptions import VerifyMismatchError, InvalidHashError
class Argon2Algorithm:
"""Argon2id password hashing algorithm."""
identifier = "argon2"
def __init__(self):
"""Initialize with default Argon2 parameters."""
self._hasher = PasswordHasher()
def hash(self, password: str, **kwargs) -> tuple[str, str]:
"""Hash a password using Argon2id.
Note: Argon2 generates its own salt internally and returns
a complete hash string that includes the salt and parameters.
We return empty string for salt_b64 and the full hash as hash_b64.
"""
hash_string = self._hasher.hash(password)
# Return empty salt since Argon2 embeds salt in hash
return ("", base64.b64encode(hash_string.encode("utf-8")).decode("utf-8"))
def verify(
self,
password: str,
salt_b64: str,
hash_b64: str,
**kwargs,
) -> bool:
"""Verify a password against Argon2 hash.
Note: salt_b64 is ignored since Argon2 embeds salt in the hash.
"""
try:
hash_string = base64.b64decode(hash_b64, validate=True).decode("utf-8")
self._hasher.verify(hash_string, password)
return True
except (VerifyMismatchError, InvalidHashError, binascii.Error, ValueError, UnicodeDecodeError):
return False
from algorithms import register_algorithm
# Auto-register when module is imported
register_algorithm(Argon2Algorithm())