Java和.NET的DES互通加密算法（转）

java加解密:

public class Encrypt
{
    public Encrypt()
    {
    }
    public static String eCode(String needEncrypt)  throws Exception
    {
        byte result[] = null;
        try
        {
            Cipher enCipher = Cipher.getInstance("DES");
            javax.crypto.SecretKey key = Key.loadKey();
            enCipher.init(1, key);
            result = enCipher.doFinal(needEncrypt.getBytes());
            BASE64Encoder b = new BASE64Encoder();
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            b.encode(result, bos);
            result = bos.toByteArray();
        }
        catch(Exception e)
        {
            throw e;
        }
        return new String(result);
    }
    public static String dCode(byte result[])
        throws Exception
    {
        String s = null;
        String key = "";
        try
        {
         Cipher deCipher = Cipher.getInstance("DES");
            deCipher.init(2, Key.loadKey());
            BASE64Decoder d = new BASE64Decoder();
            result = d.decodeBuffer(new String(result));
            byte[] iv = deCipher.getIV();
            byte strByte[] = deCipher.doFinal(result);
            s = new String(strByte);
        }
        catch(Exception e)
        {
            throw e;
        }
        return s;
    }
}
注:Key.loadKey()实现从配置文件中读取key,然后base64解码，封装在SecretKey对象中。

原：http://blog.sina.com.cn/s/blog_6d51d25e0100lp28.html

.Net解密:

（详见：http://www.cnblogs.com/ryhan/archive/2012/08/28/2660372.html）

private string dCode(string str,string strKey)
  {
   byte[] bStr = Convert.FromBase64String(str);
   byte[] key  = Convert.FromBase64String(strKey);
   DES des = new DESCryptoServiceProvider();
   des.Mode = System.Security.Cryptography.CipherMode.ECB;
   des.Key = key;
   des.IV = new byte[8];
   byte[] resultBytes = des.CreateDecryptor().TransformFinalBlock(bStr, 0, bStr.Length);
   return System.Text.Encoding.UTF8.GetString(resultBytes);
  }
 
 算法区别：
 1.java和.net默认的加密模式不同，java是ECB模式，.net是CBC模式。如果.net不手工指定ECB模式的话，在bStr.length>8时会抛异常。
 2.java和.net默认初始化向量(IV)不同，java中如不指定IV,则自动以byte[8]初始化，而.net会抛异常,要des.IV = new byte[8];