Python2 的解密函数

[ddcatgg]

首页的 PyCookieCloud 是基于 Python3 的，因此如果有人还在使用 Python2 环境，可以通过下面的 decrypt_cryptojs_aes 函数进行解密（由 ChatGPT 参考首页的 go语言实现，略作修改）：

# -*- coding: utf-8 -*-
import base64
import hashlib

import requests
from Crypto.Cipher import AES
from Crypto.Util.Padding import unpad

PKCS5_SALT_LEN = 8


def bytes_to_key(salt, data, hash_type, key_len, block_len):
    salt_len = len(salt)
    if salt_len > 0 and salt_len != PKCS5_SALT_LEN:
        raise ValueError('Salt length is %d, expected %d' % (salt_len, PKCS5_SALT_LEN))

    concat = b''
    last_hash = b''
    total_len = key_len + block_len

    while len(concat) < total_len:
        h = hashlib.new(hash_type)
        h.update(last_hash + data + salt)
        last_hash = h.digest()
        concat += last_hash

    return concat[:key_len], concat[key_len:total_len]


def decrypt_cryptojs_aes(password, ciphertext):
    raw_encrypted = base64.b64decode(ciphertext)
    if len(raw_encrypted) < 16 or raw_encrypted[:8] != b'Salted__':
        raise ValueError('Invalid ciphertext')

    salt = raw_encrypted[8:16]
    encrypted = raw_encrypted[16:]

    key, iv = bytes_to_key(salt, password.encode('utf-8'), 'md5', 32, 16)
    cipher = AES.new(key, AES.MODE_CBC, iv)
    decrypted = cipher.decrypt(encrypted)
    try:
        return unpad(decrypted, AES.block_size).decode('utf-8')
    except ValueError:
        raise ValueError('Incorrect password or corrupted data')


def main():
    uuid = 'xxxx'
    password = 'yyyy'

    url = 'http://your_server:8088/get/%s' % uuid
    d = requests.get(url).json()
    ciphertext = d['encrypted']

    key_password = hashlib.md5('-'.join([uuid, password])).hexdigest()[:16]
    decrypted = decrypt_cryptojs_aes(key_password, ciphertext)
    print(decrypted)


if __name__ == '__main__':
    main()

测试通过的软件版本：
Python：2.7
pycryptodome：3.20.0
requests：2.27.1

[easychen]

感谢分享，已添加到首页。