python 中的 DES 无法使用 pycrypto 获得正确的编码数据

Question

我在java中有一个加密数据的算法，我想在python.But中重写它这两个算法不能得到相同的编码数据。 java 代码是：

String strDefaultKey = "QabC-+50";
Key key = new SecretKeySpec(strDefaultKey.getBytes("UTF-8"), "DES");
encryptCipher = Cipher.getInstance(DES_ECB);
encryptCipher.init(Cipher.ENCRYPT_MODE, key);
String seed = "2016-09-19 05:11";
MessageDigest md5 = MessageDigest.getInstance("MD5");
md5.update(seed.getBytes());
byte[] m = md5.digest();
encryptCipher.doFinal(m);
byte[] encodeUrl = Base64.encodeBase64(sEncription.encrypt(m));
String finalUrl = new String(encodeUrl);
finalResult = finalUrl.substring(2, 8) + finalUrl.substring(10, 13);

我的python代码是：

m = 'QabC-+50'
text = '2016-09-19 05:11'
md5 = MD5.new()
md5.update(text)
text = md5.hexdigest()

cipher = DES.new(m, DES.MODE_ECB)
text_temp = cipher.encrypt(text)
final_str = base64.b64encode(text_temp)
print final_str
print final_str[2:8] + final_str[10:13]
print type(text_temp)

两个版本代码不能得到相同的最终字符串。有人知道为什么吗？

Answer 1

你的加密逻辑没问题，两种方法的区别在于它们的MD5结果。

没有 MD5 步骤：

Java代码（不知道你的sEncription是什么，去掉）：

import java.security.Key;
import java.security.MessageDigest;
import java.util.Base64;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;


public class H {
    public static void main(String args[]){
        try{
        String strDefaultKey = "QabC-+50";
        Key key = new SecretKeySpec(strDefaultKey.getBytes("UTF-8"), "DES");
        Cipher encryptCipher = Cipher.getInstance("DES/ECB/NoPadding");
        encryptCipher.init(Cipher.ENCRYPT_MODE, key);
        String seed = "2016-09-19 05:11";
        byte[] a = encryptCipher.doFinal(seed.getBytes());
        byte[] encodeUrl = Base64.getEncoder().encode(a);
//      byte[] encodeUrl = Base64.encodeBase64(sEncription.encrypt(m));
        String finalUrl = new String(encodeUrl);
        String finalResult = finalUrl.substring(2, 8) + finalUrl.substring(10, 13);
        System.out.println(finalUrl);
        System.out.println(finalResult);
        }catch(Exception e){
            e.printStackTrace();
        }
    }
}

输出：

Wm+DLy8m9G2BJnH2wvtKvA==
+DLy8m2BJ

Python代码：

from Crypto.Hash import MD5
from Crypto.Cipher import DES
import base64

m = 'QabC-+50'
text = '2016-09-19 05:11'
md5 = MD5.new()
md5.update(text)
# text = md5.hexdigest()
cipher = DES.new(m, DES.MODE_ECB)
text_temp = cipher.encrypt(text)
print 'text_temp is ', text_temp
final_str = base64.b64encode(text_temp)
print final_str
print final_str[2:8] + final_str[10:13]

输出：

Wm+DLy8m9G2BJnH2wvtKvA==
+DLy8m2BJ

所以没有 MD5 步骤，java 代码和 python 代码有一些输出。

重要的是 java 代码中的 MD5 方法，它不是获取字符串 MD5 值的正确方法。

下面的代码包含获取字符串的 MD5 值的正确方法：

import java.security.Key;
import java.security.MessageDigest;
import java.util.Base64;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;


public class H {
    public static void main(String args[]){
        try{
        String strDefaultKey = "QabC-+50";
        Key key = new SecretKeySpec(strDefaultKey.getBytes("UTF-8"), "DES");
        Cipher encryptCipher = Cipher.getInstance("DES/ECB/NoPadding");
        encryptCipher.init(Cipher.ENCRYPT_MODE, key);
        String seed = "2016-09-19 05:11";
        String seedMd5 = MD5(seed);
        byte[] a = encryptCipher.doFinal(seedMd5.getBytes());
        byte[] encodeUrl = Base64.getEncoder().encode(a);
        String finalUrl = new String(encodeUrl);
        String finalResult = finalUrl.substring(2, 8) + finalUrl.substring(10, 13);
        System.out.println(finalUrl);
        System.out.println(finalResult);
        }catch(Exception e){
            e.printStackTrace();
        }
    }

    static String MD5(String src) {
        MessageDigest md;
        try {
            md = MessageDigest.getInstance("MD5");
            StringBuffer deviceIDString = new StringBuffer(src);
            src = convertToHex(md.digest(deviceIDString.toString().getBytes()));
        } catch (Exception e) {
            src = "00000000000000000000000000000000";
        }
        return src;
    }

    private static String convertToHex(byte[] data) {
        StringBuffer buf = new StringBuffer();
        for (int i = 0; i < data.length; i++) {
            int halfbyte = (data[i] >>> 4) & 0x0F;
            int two_halfs = 0;
            do {
                if ((0 <= halfbyte) && (halfbyte <= 9))
                    buf.append((char) ('0' + halfbyte));
                else
                    buf.append((char) ('a' + (halfbyte - 10)));
                halfbyte = data[i] & 0x0F;
            } while (two_halfs++ < 1);
        }
        return buf.toString();
    }
}

输出：

c/C16RAE1fADZXNi2H0YlevNhuucGYYHGVQ7v0Eoo9w=
C16RAEADZ

Python代码：

from Crypto.Hash import MD5
from Crypto.Cipher import DES
import base64

m = 'QabC-+50'
text = '2016-09-19 05:11'
md5 = MD5.new()
md5.update(text)
text = md5.hexdigest()
cipher = DES.new(m, DES.MODE_ECB)
text_temp = cipher.encrypt(text)
final_str = base64.b64encode(text_temp)
print final_str
print final_str[2:8] + final_str[10:13]

输出：

c/C16RAE1fADZXNi2H0YlevNhuucGYYHGVQ7v0Eoo9w=
C16RAEADZ

现在一切正常！ :)

python 中的 DES 无法使用 pycrypto 获得正确的编码数据

DES in python can't get the correct encoded data using pycrypto

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python-2.7

encryption

des