https://my.oschina.net/leejun2005/blog/586451

手头有个 Java 版的 DES 加密/解密程序，最近想着将其 Python 重构下，方便后续脚本解析，捣鼓了两下 pyDes 貌似很方便，不过据网上其他同学测试说 PyCrypto 性能要比 pyDes 高一个数量级，这里我没有做具体性能测试，也没有选用 PyCrypto 主要原因有三：

（1）PyCrypto 在 windows 下依赖 VC++9.0，安装麻烦

（2）PyCrypto 默认不支持 padmode，且对秘钥以及偏转向量长度有严格要求，扩展性很差

（3）不是用来搞暴力破解，性能要求不高，所以就不关注性能了，能用就行 ^ _ ^

下面直接上代码吧~

1、Java 版

public class EncryptHelper {
    private static String strKey = "test_KEY", strParam = "test__IV";
    public static String desEncrypt(String source) throws Exception {
        if (source == null || source.length() == 0)
            return null;
        Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
        DESKeySpec desKeySpec = new DESKeySpec(strKey.getBytes("UTF-8"));
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
        SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
        IvParameterSpec iv = new IvParameterSpec(strParam.getBytes("UTF-8"));
        cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv);
        return StringHelper.toHexString(
                cipher.doFinal(source.getBytes("UTF-8"))).toUpperCase();
    }

    public static String desDecrypt(String source) throws Exception {
        if (source == null || source.length() == 0)
            return null;
        byte[] src = StringHelper.fromHexString(source);
        Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
        DESKeySpec desKeySpec = new DESKeySpec(strKey.getBytes("UTF-8"));
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
        SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
        IvParameterSpec iv = new IvParameterSpec(strParam.getBytes("UTF-8"));
        cipher.init(Cipher.DECRYPT_MODE, secretKey, iv);
        byte[] retByte = cipher.doFinal(src);
        return new String(retByte);
    }

    public static void main(String[] args) throws Exception {
        System.out
        .println(EncryptHelper
                .desDecrypt("886f930f65f29132f6ace2683c448b5580d681a1fec3fc91cf3161f074b53b935d1c8fe80f99201077b36f923a42ac0e05cabe579308fda08d8ff463ad334677"));
        System.out.println(EncryptHelper.desEncrypt("https://mail.google.com/mail/u/0/#inbox/a1ed0e2f6f28e06b4361"));
    }
}

//结果：
//https://mail.google.com/mail/u/0/#inbox/a1ed0e2f6f28e06b4361
//886F930F65F29132F6ACE2683C448B5580D681A1FEC3FC91CF3161F074B53B935D1C8FE80F99201077B36F923A42AC0E05CABE579308FDA08D8FF463AD334677

2、Python 版

# -*- coding:utf-8 -*-
import sys

reload(sys)
sys.setdefaultencoding('utf-8')
from pyDes import *
from binascii import b2a_hex, a2b_hex

# For Python3, you'll need to use bytes, i.e.:
#   data = b"Please encrypt my data"
#   k = des(b"DESCRYPT", CBC, b"\0\0\0\0\0\0\0\0", pad=None, padmode=PAD_PKCS5)

data = 'https://mail.google.com/mail/u/0/#inbox/a1ed0e2f6f28e06b4361'
KEY = "test_KEY"    #密钥
IV = "test__IV"     #偏转向量
# 使用DES对称加密算法的CBC模式加密
k = des(KEY, CBC, IV, pad=None, padmode=PAD_PKCS5)
d = k.encrypt(data)
print b2a_hex(d)
print "Decrypted: %r" % k.decrypt(d)

#结果：
#886f930f65f29132f6ace2683c448b5580d681a1fec3fc91cf3161f074b53b935d1c8fe80f99201077b36f923a42ac0e05cabe579308fda08d8ff463ad334677
#Decrypted: ' 

#或者单行命令如下：
python -c 'from pyDes import *;from binascii import a2b_hex;import sys;print des("test_KEY", CBC, "test__IV", pad=None, padmode=PAD_PKCS5).decrypt(a2b_hex(sys.stdin.readlines()[0].strip()))' <<<886f930f65f29132f6ace2683c448b5580d681a1fec3fc91cf3161f074b53b935d1c8fe80f99201077b36f923a42ac0e05cabe579308fda08d8ff463ad334677
#https://mail.google.com/mail/u/0/#inbox/a1ed0e2f6f28e06b4361