早晨的时候,一个朋友在MSN上问我.NET的DES算法实现。我说,这不是很简单的,.NET Framework都有现成的封装直接用就可以了。仔细一问,原来他要和一个.NET实现的系统进行数据交换,他的DES的Java实现出来的结果和.NET的不一样。所以,他怀疑.NET那边的实现有问题。好吧,程序员们都是如此自负,自己从来都不会出问题的-_-||
DES算是相当成熟的算法了,就不再赘述了。要加密结果一样,其实很简单,只要IV值和密钥一样,出来的结果应该都是一样的。看到他那边的.NET实现之后,IV是一个空的byte数组,Java这边只要也把IV的值设为空的byte数组的,结果应该就是一样的。思路就是这样的,下面就是实现了。
.NET的DES算法实现
根据密钥加密字符串
public static string EncryptDES(string encryptString, string encryptKey)
{
DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider();
byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey);
byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
MemoryStream mStream = new MemoryStream();
CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, new byte[8]), CryptoStreamMode.Write);
cStream.Write(inputByteArray, 0, inputByteArray.Length);
cStream.FlushFinalBlock();
return Convert.ToBase64String(mStream.ToArray());
}
根据密钥解密字符串
public static string DecryptDES(string decryptString, string decryptKey)
{
byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey);
byte[] inputByteArray = Convert.FromBase64String(decryptString);
DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
MemoryStream mStream = new MemoryStream();
CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, new byte[8]), CryptoStreamMode.Write);
cStream.Write(inputByteArray, 0, inputByteArray.Length);
cStream.FlushFinalBlock();
return Encoding.UTF8.GetString(mStream.ToArray());
}
Java的DES算法实现
根据密钥加密字符串
public static String encryptDES(String encryptString, String encryptKey) throws Exception {
IvParameterSpec zeroIv = new IvParameterSpec(new byte[8]);
SecretKeySpec key = new SecretKeySpec(encryptKey.getBytes(), "DES");
Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, key, zeroIv);
byte[] encryptedData = cipher.doFinal(encryptString.getBytes());
return new BASE64Encoder().encode(encryptedData);
}
根据密钥解密字符串
public static String decryptDES(String decryptString, String decryptKey) throws Exception {
byte[] byteMi = new BASE64Decoder().decodeBuffer(decryptString);
IvParameterSpec zeroIv = new IvParameterSpec(new byte[8]);
SecretKeySpec key = new SecretKeySpec(decryptKey.getBytes(), "DES");
Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key, zeroIv);
byte decryptedData[] = cipher.doFinal(byteMi);
return new String(decryptedData);
}
其实这个问题并不难解决,只是网上一些DES的算法的例子代码并没有用到IV,容易让人产生误解。