在Python中解密使用.NET加密的字符串

Question

我正在尝试使用C#加密字符串并使用Python解密它.加密/解密部分按预期工作(即我能够解密我最初加密的字符串).但是,Python返回的字符串在开头有2个额外的字节,每个字符用空格分隔.

**Original string** (before encryption -- encrypted using C#) = "Something you want to keep private with AES"

**Decrypted string** (using Python) = "??S o m e t h i n g  y o u   w a n t   t o   k e e p   p r i v a t e   w i t h  A E S"

为什么我在字符串的开头得到这两个额外的字节？为什么解密字符串中的所有空格？知道为什么吗？

谢谢!

使用C#加密

public static string Encrypt<T>(string value, string password, string salt)
         where T : SymmetricAlgorithm, new()
{
    DeriveBytes rgb = new Rfc2898DeriveBytes(password, Encoding.Unicode.GetBytes(salt));

    SymmetricAlgorithm algorithm = new T();

    byte[] rgbKey = rgb.GetBytes(algorithm.KeySize >> 3);
    byte[] rgbIV = rgb.GetBytes(algorithm.BlockSize >> 3);

    ICryptoTransform transform = algorithm.CreateEncryptor(rgbKey, rgbIV);

    using (MemoryStream buffer = new MemoryStream())
    {
        using (CryptoStream stream = new CryptoStream(buffer, transform, CryptoStreamMode.Write))
        {
            using (StreamWriter writer = new StreamWriter(stream, Encoding.Unicode))
            {
                writer.Write(value);
            }
        }

        return Convert.ToBase64String(buffer.ToArray());
    }
}


string plain = "Something you want to keep private with AES";
string encrypted = CipherUtility.Encrypt<AesManaged>(plain, "password", "salt");

用Python + pycrypto解密

import base64, sys
import Crypto.Cipher.AES

password = base64.b64decode('PSCIQGfoZidjEuWtJAdn1JGYzKDonk9YblI0uv96O8s=') # See rgbKey
salt = base64.b64decode('ehjtnMiGhNhoxRuUzfBOXw==') # See rgbIV
aes = Crypto.Cipher.AES.new(password, Crypto.Cipher.AES.MODE_CBC, salt)
text = base64.b64decode('QpHn/fnraLswwI2Znt1xTaBzRtDqO4V5QI78jLOlVsbvaIs0yXMUlqJhQtK+su2hYn28G2vNyLkj0zLOs+RIjElCSqJv1aK/Yu8uY07oAeStqRt4u/DVUzoWlxdrlF0u')

print aes.decrypt(text)

Answer 1

使用UTF-16编码将字符串编码为字节.前两个字节是BOM.然后将每个字符编码为两个字节.

从以下文档Encoding.Unicode:

使用little endian字节顺序获取UTF-16格式的编码.

要获取原始字符串,您需要将其从UTF-16字节解码回Unicode字符串.

print aes.decrypt(text).decode('utf-16')