将C#decryption转换为Python PyDes

时间:2011-05-05 19:33:09

标签: c# python encryption tripledes

我无法将代码从C#转换为Python。在Martijn's C# Blog处加密是一个很好的加密/解密程序[包含在下面],但是我不能让它直接转换为python版本pyDes [下面的示例]

    public static string DecryptString(string Message, string Passphrase)
    {
        byte[] Results;
        System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();

        // Step 1. We hash the passphrase using MD5
        // We use the MD5 hash generator as the result is a 128 bit byte array
        // which is a valid length for the TripleDES encoder we use below

        MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider();
        byte[] TDESKey = HashProvider.ComputeHash(UTF8.GetBytes(Passphrase));

        // Step 2. Create a new TripleDESCryptoServiceProvider object
        TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider();

        // Step 3. Setup the decoder
        TDESAlgorithm.Key = TDESKey;
        TDESAlgorithm.Mode = CipherMode.ECB;
        TDESAlgorithm.Padding = PaddingMode.PKCS7;

        // Step 4. Convert the input string to a byte[]
        byte[] DataToDecrypt = Convert.FromBase64String(Message);

        // Step 5. Attempt to decrypt the string
        try
        {
            ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();
            Results = Decryptor.TransformFinalBlock(DataToDecrypt, 0, DataToDecrypt.Length);
        }
        finally
        {
            // Clear the TripleDes and Hashprovider services of any sensitive information
            TDESAlgorithm.Clear();
            HashProvider.Clear();
        }

        // Step 6. Return the decrypted string in UTF8 format
        return UTF8.GetString( Results );
    }

PyDES:

from pyDes import *


data = "Please encrypt my data"
k = des("DESCRYPT", ECB, "\0\0\0\0\0\0\0\0", pad=None, padmode=PAD_PKCS5)
d = k.encrypt(data)
print "Encrypted: %r" % d
print "Decrypted: %r" % k.decrypt(d)
assert k.decrypt(d, padmode=PAD_PKCS5) == dat

我修改了原始pyDes以使用ECB而不是CBC。 没有一个字符串匹配,我在我的绳子的尽头。 请帮忙! 感谢

1 个答案:

答案 0 :(得分:9)

没关系---想通了。

如果在pyDes中更改此行

print "Encrypted: %r" % d

print "Encrypted: %r" % d.encode('base64')

然后代码完全匹配。

要进行比较,请运行Martijn网站上的原始代码:[输出]

Message: This world is round, not flat, don't believe them!
Password: secret
Encrypted string: pafHnI124lxzCr+93COqxfgOTan8x9oPzX4R/PDYkBnrjufk0/7mesG5tmS2AU
Pxna3z0jY+7II=
Decrypted string: This world is round, not flat, don't believe them!

以下是来自pyDes的修改代码 - 您需要使用md5Hash

填充密码
import md5
from pyDes import *

Msg = "This world is round, not flat, don't believe them!"
Password = "secret"

m=md5.new()
m.update(Password)

k = triple_des(m.digest() , ECB,padmode=PAD_PKCS5)
d = k.encrypt(Msg)

print "Encrypted: %r" % d.encode('base64')  
print "Decrypted: %r" % k.decrypt(d)
assert k.decrypt(d, padmode=PAD_PKCS5) == Msg

输出:

Encrypted: 'pafHnI124lxzCr+93COqxfgOTan8x9oPzX4R/PDYkBnrjufk0/7mesG5tmS2AUPxna3z
0jY+7II=\n'
Decrypted: "This world is round, not flat, don't believe them!"

我希望这有助于下一个人!!!! 谢谢 -D