"""M2Crypto wrapper for OpenSSL RC4 API.
Copyright (c) 1999-2003 Ng Pheng Siong. All rights reserved."""
from typing import Optional
from M2Crypto import m2, types as C
[docs]
class RC4(object):
"""Object interface to the stream cipher RC4."""
def __init__(self, key: Optional[bytes] = None) -> None:
self.cipher = m2.rc4_new()
if key:
m2.rc4_set_key(self.cipher, key)
[docs]
@staticmethod
def rc4_free(cipher: C.RC4_KEY) -> None:
m2.rc4_free(cipher)
def __del__(self) -> None:
if getattr(self, "cipher", None):
self.rc4_free(self.cipher)
[docs]
def set_key(self, key: bytes) -> None:
m2.rc4_set_key(self.cipher, key)
[docs]
def update(self, data: bytes) -> bytes:
return m2.rc4_update(self.cipher, data)
[docs]
def final(self) -> str:
return ""