# Pyrogram - Telegram MTProto API Client Library for Python # Copyright (C) 2017-2018 Dan Tès # # This file is part of Pyrogram. # # Pyrogram is free software: you can redistribute it and/or modify # it under the terms of the GNU Lesser General Public License as published # by the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # Pyrogram is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public License # along with Pyrogram. If not, see . # from pyaes import AES import tgcrypto BLOCK_SIZE = 16 # TODO: Performance optimization class IGE: @classmethod def encrypt(cls, data: bytes, key: bytes, iv: bytes) -> bytes: return tgcrypto.ige_encrypt(data, key, iv) # return cls.ige(data, key, iv, True) @classmethod def decrypt(cls, data: bytes, key: bytes, iv: bytes) -> bytes: return tgcrypto.ige_decrypt(data, key, iv) # return cls.ige(data, key, iv, False) @staticmethod def xor(a: bytes, b: bytes) -> bytes: return int.to_bytes( int.from_bytes(a, "big") ^ int.from_bytes(b, "big"), len(a), "big", ) # @classmethod # def ige(cls, data: bytes, key: bytes, iv: bytes, encrypt: bool) -> bytes: # cipher = AES(key) # # iv_1 = iv[:BLOCK_SIZE] # iv_2 = iv[BLOCK_SIZE:] # # data = [data[i: i + BLOCK_SIZE] for i in range(0, len(data), BLOCK_SIZE)] # # if encrypt: # for i, chunk in enumerate(data): # iv_1 = data[i] = cls.xor(cipher.encrypt(cls.xor(chunk, iv_1)), iv_2) # iv_2 = chunk # else: # for i, chunk in enumerate(data): # iv_2 = data[i] = cls.xor(cipher.decrypt(cls.xor(chunk, iv_2)), iv_1) # iv_1 = chunk # # return b"".join(data)