认识达内从这里开始

首先，对于一个公司，即有.net又有java开发来说，加解密是需要相互打通的，因为，根据莫非定律你迟早会有“.net加密让java解密“的情况。

.net实现public static string Encrypt(SymmetricAlgorithm algorithm, string plaintext, string key)

{

TripleDESCryptoServiceProvider tripleDes = new TripleDESCryptoServiceProvider();

MD5CryptoServiceProvider hashMD5 = new MD5CryptoServiceProvider();

algorithm.Key = hashMD5.ComputeHash(ASCIIEncoding.ASCII.GetBytes(key));

algorithm.Mode = CipherMode.ECB;

Console.WriteLine("IV=" + Convert.ToBase64String(algorithm.IV));

ICryptoTransform transformer = algorithm.CreateEncryptor();

byte[] Buffer = ASCIIEncoding.ASCII.GetBytes(plaintext);

byte[] result = transformer.TransformFinalBlock(Buffer, 0, Buffer.Length);

return Convert.ToBase64String(result);

}

.net和java的几个不同byte类型对于.net是(0255)，而java来说它是有符号的，是(-128127)

对于DES来说，默认的java支持的密钥是8字节，而.net里algorithm.Key是16个字节，所以用原生Java的des是不能和.net互通的

java实现需要第三方包bcprov-jdk15on

dependency

groupId org.bouncycastle /groupId

artifactId bcprov-jdk15on /artifactId

version 1.64 /version>

scope compile /scope>

/dependency

实现与.net互通的加密过程

private static final String ALGORITHM = "DESede";

private static final String CIPHER_TRANSFER = "DESede/ECB/PKCS5Padding";

private static final String ENCODING = "UTF-8";

static {

init();

}

public static void init() {

BouncyCastleProvider bouncyCastleProvider = new BouncyCastleProvider();

Security.addProvider(bouncyCastleProvider);

}

/**

* 初始化key.

*

* @param key

*/

@SneakyThrows

static SecretKey getSecretKey(String key) {

MessageDigest md5 = MessageDigest.getInstance("MD5");

byte[] bkeys = md5.digest(key.getBytes());

SecretKey secretKey = new SecretKeySpec(bkeys, ALGORITHM);

return secretKey;

}

/**

* 字符串加密.

*

* @param plainText

* @param key

* @return

* @throws Exception

*/

@SneakyThrows

public static String encryptToBase64(String plainText, String key) {

SecretKey secretKey = getSecretKey(key);

Cipher cipher = Cipher.getInstance(CIPHER_TRANSFER);

cipher.init(Cipher.ENCRYPT_MODE, secretKey);

byte[] result = cipher.doFinal(plainText.getBytes(ENCODING));

String s1 = Base64.encodeBase64String(result);

return s1;

}

上面代码，主要是对于key的生成要注意，使用了与.net相同的md5对原始key进行的加密，保存它是16个字节。