DES 加密解密C#和JAVA 互通

遇到的问题如下：

主要就是C#和JAVA中的DES不一致的问题。

1.  是C#采用CBC Mode，PKCS7 Padding, Java采用CBC Mode，PKCS5Padding Padding,
2.  是C#采用ECB Mode，PKCS7 Padding, Java采用ECB Mode，PKCS5Padding Padding,   
     C#的ECB有IV向量，JAVA中的ECB不支持向量。

在实际解决中我采用了ECB的方式，把C#的IV向量和Key公用同一个加密字符串。在C#和JAVA中都转为16进制的加密串，解决匹配不上的问题。最后封一层base64。

C#：

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

namespace BiHu.BaoXian.Service.Database.Extension
{
    /** DES加密解密
     * @author  liucx
     * @description  DES+base64加密解密
     */
    public static class EncodHelper
    {
        #region DESEnCode DES加密
        public static string DESEnCode(string pToEncrypt, string sKey)
        {
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            byte[] inputByteArray = Encoding.GetEncoding("UTF-8").GetBytes(pToEncrypt);

            //建立加密对象的密钥和偏移量
            //原文使用ASCIIEncoding.ASCII方法的GetBytes方法
            //使得输入密码必须输入英文文本
            des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
            des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
            MemoryStream ms = new MemoryStream();
            CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);

            cs.Write(inputByteArray, 0, inputByteArray.Length);
            cs.FlushFinalBlock();

            StringBuilder ret = new StringBuilder();
            //16进制
            foreach (byte b in ms.ToArray())
            {
                ret.AppendFormat("{0:X2}", b);
            }

            //完成加密后再转一次base64
            byte[] bytes = Encoding.UTF8.GetBytes(ret.ToString());
            var result = Convert.ToBase64String(bytes);
            return result;
        }
        #endregion

        #region DESDeCode DES解密
        public static string DESDeCode(string code, string sKey)
        {
            //解密先转码base64
            var pToDecrypt = Encoding.UTF8.GetString(Convert.FromBase64String(code));
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            byte[] inputByteArray = new byte[pToDecrypt.Length / 2];
            for (int x = 0; x < pToDecrypt.Length / 2; x++)
            {
                int i = (Convert.ToInt32(pToDecrypt.Substring(x * 2, 2), 16));
                inputByteArray[x] = (byte)i;
            }

            des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
            des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
            MemoryStream ms = new MemoryStream();
            CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
            cs.Write(inputByteArray, 0, inputByteArray.Length);
            cs.FlushFinalBlock();

            StringBuilder ret = new StringBuilder();

            return System.Text.Encoding.UTF8.GetString(ms.ToArray());
        }
        #endregion
    }
}

JAVA

package com.util;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

import javax.crypto.spec.IvParameterSpec;
import org.apache.commons.codec.binary.Base64;

/**
 * DES加密，和C#中对应
 * 
 * @author liucx
 * @date 2018/4/10
 */
public class DESUtils {
	/**
	 * 密钥
	 */
	public static final String DEFAULT_KEY = "liucx2018";

	/**
	 * 加密
	 * 
	 * @param message
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static byte[] encrypt(String message, String key) throws Exception {
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");

		DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));

		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
		SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
		IvParameterSpec iv = new IvParameterSpec(key.getBytes("UTF-8"));
		cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv);

		return cipher.doFinal(message.getBytes("UTF-8"));
	}

	/**
	 * 加密，方式为先DES加密， 再base64转码的字符串
	 * @param message
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static String encrypt_base64(String message, String key) throws Exception {
		String a = toHexString(encrypt(message, key)).toUpperCase();
		String base64message =  new String(Base64.encodeBase64(a.getBytes("UTF-8")));
		return base64message;
	}

	/**
	 * 解密
	 * 
	 * @param message
	 *            加密后的内容
	 * @param key
	 *            密钥
	 * @return
	 * @throws Exception
	 */
	public static String decrypt(String message, String key) throws Exception {
		
		byte[] bytesrc = convertHexString(message);
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));
		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
		SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
		IvParameterSpec iv = new IvParameterSpec(key.getBytes("UTF-8"));

		cipher.init(Cipher.DECRYPT_MODE, secretKey, iv);

		byte[] retByte = cipher.doFinal(bytesrc);
		return new String(retByte, "UTF-8");
	}

	

	
	/**
	 * 解密，方式为先解码base64，再解密，转成正常字符串
	 * 
	 * @param message base64编码的密文
	 * @param key     密钥
	 * @return        解密后的文本
	 * @throws Exception
	 */
	public static String decrypt_base64(String base64message, String key) throws Exception {
		String message = new String(Base64.decodeBase64(base64message.getBytes("UTF-8")));
		String result = decrypt(message, key);
		return result;
	}
	/**
	 * 转成16进制
	 * 
	 * @param b
	 * @return
	 */
	public static String toHexString(byte b[]) {
		StringBuffer hexString = new StringBuffer();
		for (int i = 0; i < b.length; i++) {
			String plainText = Integer.toHexString(0xff & b[i]);
			if (plainText.length() < 2)
				plainText = "0" + plainText;
			hexString.append(plainText);
		}

		return hexString.toString();
	}
	
	public static byte[] convertHexString(String ss) {
		byte digest[] = new byte[ss.length() / 2];
		for (int i = 0; i < digest.length; i++) {
			String byteString = ss.substring(2 * i, 2 * i + 2);
			int byteValue = Integer.parseInt(byteString, 16);
			digest[i] = (byte) byteValue;
		}

		return digest;
	}
}