import java.math.BigInteger;
import java.security.InvalidKeyException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import javax.crypto.KeyGenerator;
import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.codec.binary.Base64;public class MyEncrypt {
public static final String KEY_SHA = "SHA";
public static final String KEY_MD5 = "MD5";
public static final String KEY_MAC = "HmacMD5";// sun不推荐使用它们自己的base64,用apache的挺好
/**
* BASE64解密
*/
public static byte[] decryptBASE64(byte[] dest) {
if (dest == null) {
return null;
}
return Base64.decodeBase64(dest);
}/**
* BASE64加密
*/
public static byte[] encryptBASE64(byte[] origin) {
if (origin == null) {
return null;
}
return Base64.encodeBase64(origin);
}/**
* MD5加密
* 
* @throws NoSuchAlgorithmException
*/
public static byte[] encryptMD5(byte[] data)
throws NoSuchAlgorithmException {
if (data == null) {
return null;
}
MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);
md5.update(data);
return md5.digest();
}/**
* SHA加密
* 
* @throws NoSuchAlgorithmException
*/
public static byte[] encryptSHA(byte[] data)
throws NoSuchAlgorithmException {
if (data == null) {
return null;
}
MessageDigest sha = MessageDigest.getInstance(KEY_SHA);
sha.update(data);
return sha.digest();
}/**
* 初始化HMAC密钥
* 
* @throws NoSuchAlgorithmException
*/
public static String initMacKey() throws NoSuchAlgorithmException {
KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_MAC);
SecretKey secretKey = keyGenerator.generateKey();
return new String(encryptBASE64(secretKey.getEncoded()));
}/**
* HMAC加密
* 
* @throws NoSuchAlgorithmException
* @throws InvalidKeyException
*/
public static byte[] encryptHMAC(byte[] data, String key)
throws NoSuchAlgorithmException, InvalidKeyException {
SecretKey secretKey = new SecretKeySpec(decryptBASE64(key.getBytes()),
KEY_MAC);
Mac mac = Mac.getInstance(secretKey.getAlgorithm());
mac.init(secretKey);
return mac.doFinal(data);}public static void main(String[] args) throws Exception {
// TODO Auto-generated method stub
String data = "简单加密";
System.out.println(new BigInteger(encryptBASE64(data.getBytes())).toString(16));
System.out.println(new BigInteger(encryptBASE64(data.getBytes())).toString(32));
System.out.println(new String(decryptBASE64(encryptBASE64(data.getBytes()))));System.out.println(new BigInteger(encryptMD5(data.getBytes())).toString());
System.out.println(new BigInteger(encryptSHA(data.getBytes())).toString());System.out.println(new BigInteger(encryptHMAC(data.getBytes(), initMacKey())).toString());
}}

可变MD5加密(Java实现)

可变在这里含义很简单，就是最终的加密结果是可变的，而非必需按标准MD5加密实现。Java类库security中的MessageDigest类就提供了MD5加密的支持，实现起来非常方便。为了实现更多效果，我们可以如下设计MD5工具类。

import java.security.MessageDigest;/*** 标准MD5加密方法，使用java类库的security包的MessageDigest类处理*/
public class MD5 {/*** 获得MD5加密密码的方法*/public static String getMD5ofStr(String origString) {String origMD5 = null;try {MessageDigest md5 = MessageDigest.getInstance("MD5");// md5.update(origString.getBytes());byte[] result = md5.digest(origString.getBytes());origMD5 = byteArray2HexStr(result);// if ("123".equals(origString)) {// System.out.println(new String(result));// System.out.println(new BigInteger(result).toString(16));// }} catch (Exception e) {e.printStackTrace();}return origMD5;}/*** 处理字节数组得到MD5密码的方法*/private static String byteArray2HexStr(byte[] bs) {StringBuffer sb = new StringBuffer();for (byte b : bs) {sb.append(byte2HexStr(b));}return sb.toString();}/*** 字节标准移位转十六进制方法*/private static String byte2HexStr(byte b) {String hexStr = null;int n = b;if (n < 0) {// 若需要自定义加密,请修改这个移位算法即可n = b & 0x7F + 128;}hexStr = Integer.toHexString(n / 16) + Integer.toHexString(n % 16);return hexStr.toUpperCase();}/*** 提供一个MD5多次加密方法*/public static String getMD5ofStr(String origString, int times) {String md5 = getMD5ofStr(origString);for (int i = 0; i < times - 1; i++) {md5 = getMD5ofStr(md5);}return getMD5ofStr(md5);}/*** 密码验证方法*/public static boolean verifyPassword(String inputStr, String MD5Code) {return getMD5ofStr(inputStr).equals(MD5Code);}/*** 重载一个多次加密时的密码验证方法*/public static boolean verifyPassword(String inputStr, String MD5Code,int times) {return getMD5ofStr(inputStr, times).equals(MD5Code);}/*** 提供一个测试的主函数*/public static void main(String[] args) {System.out.println("123:" + getMD5ofStr("123"));System.out.println("123456789:" + getMD5ofStr("123456789"));System.out.println("sarin:" + getMD5ofStr("sarin"));System.out.println("123:" + getMD5ofStr("123", 4));}
}

import java.lang.reflect.*;  /** * ********************************************** * md5 类实现了RSA Data Security, Inc.在提交给IETF * 的RFC1321中的MD5 message-digest 算法。 * *********************************************** */  public class MD5 {  /* 下面这些S11-S44实际上是一个4*4的矩阵，在原始的C实现中是用#define 实现的， 这里把它们实现成为static final是表示了只读，切能在同一个进程空间内的多个 Instance间共享*/  static final int S11 = 7;  static final int S12 = 12;  static final int S13 = 17;  static final int S14 = 22;  static final int S21 = 5;  static final int S22 = 9;  static final int S23 = 14;  static final int S24 = 20;  static final int S31 = 4;  static final int S32 = 11;  static final int S33 = 16;  static final int S34 = 23;  static final int S41 = 6;  static final int S42 = 10;  static final int S43 = 15;  static final int S44 = 21;  static final byte[] PADDING = { -128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  0 };  /* 下面的三个成员是MD5计算过程中用到的3个核心数据，在原始的C实现中 被定义到MD5_CTX结构中 */  private long[] state = new long[4]; // state (ABCD)  private long[] count = new long[2]; // number of bits, modulo 2^64 (lsb first)  private byte[] buffer = new byte[64]; // input buffer  /* digestHexStr是MD5的唯一一个公共成员，是最新一次计算结果的 16进制ASCII表示. */  public String digestHexStr;  /* digest,是最新一次计算结果的2进制内部表示，表示128bit的MD5值. */  private byte[] digest = new byte[16];  /* getMD5ofStr是类MD5最主要的公共方法，入口参数是你想要进行MD5变换的字符串 返回的是变换完的结果，这个结果是从公共成员digestHexStr取得的． */  public String getMD5ofStr(String inbuf) {  md5Init();  md5Update(inbuf.getBytes(), inbuf.length());  md5Final();  digestHexStr = "";  for (int i = 0; i < 16; i++) {  digestHexStr += byteHEX(digest[i]);  }  return digestHexStr;  }  // 这是MD5这个类的标准构造函数，JavaBean要求有一个public的并且没有参数的构造函数  public MD5() {  md5Init();  return;  }  /* md5Init是一个初始化函数，初始化核心变量，装入标准的幻数 */  private void md5Init() {  count[0] = 0L;  count[1] = 0L;  ///* Load magic initialization constants.  state[0] = 0x67452301L;  state[1] = 0xefcdab89L;  state[2] = 0x98badcfeL;  state[3] = 0x10325476L;  return;  }  /* F, G, H ,I 是4个基本的MD5函数，在原始的MD5的C实现中，由于它们是  简单的位运算，可能出于效率的考虑把它们实现成了宏，在java中，我们把它们  实现成了private方法，名字保持了原来C中的。 */  private long F(long x, long y, long z) {  return (x & y) | ((~x) & z);  }  private long G(long x, long y, long z) {  return (x & z) | (y & (~z));  }  private long H(long x, long y, long z) {  return x ^ y ^ z;  }  private long I(long x, long y, long z) {  return y ^ (x | (~z));  }  /* FF,GG,HH和II将调用F,G,H,I进行近一步变换 FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4. Rotation is separate from addition to prevent recomputation. */  private long FF(long a, long b, long c, long d, long x, long s, long ac) {  a += F(b, c, d) + x + ac;  a = ((int) a << s) | ((int) a >>> (32 - s));  a += b;  return a;  }  private long GG(long a, long b, long c, long d, long x, long s, long ac) {  a += G(b, c, d) + x + ac;  a = ((int) a << s) | ((int) a >>> (32 - s));  a += b;  return a;  }  private long HH(long a, long b, long c, long d, long x, long s, long ac) {  a += H(b, c, d) + x + ac;  a = ((int) a << s) | ((int) a >>> (32 - s));  a += b;  return a;  }  private long II(long a, long b, long c, long d, long x, long s, long ac) {  a += I(b, c, d) + x + ac;  a = ((int) a << s) | ((int) a >>> (32 - s));  a += b;  return a;  }  /* md5Update是MD5的主计算过程，inbuf是要变换的字节串，inputlen是长度，这个 函数由getMD5ofStr调用，调用之前需要调用md5init，因此把它设计成private的 */  private void md5Update(byte[] inbuf, int inputLen) {  int i, index, partLen;  byte[] block = new byte[64];  index = (int) (count[0] >>> 3) & 0x3F;  // /* Update number of bits */  if ((count[0] += (inputLen << 3)) < (inputLen << 3))  count[1]++;  count[1] += (inputLen >>> 29);  partLen = 64 - index;  // Transform as many times as possible.  if (inputLen >= partLen) {  md5Memcpy(buffer, inbuf, index, 0, partLen);  md5Transform(buffer);  for (i = partLen; i + 63 < inputLen; i += 64) {  md5Memcpy(block, inbuf, 0, i, 64);  md5Transform(block);  }  index = 0;  } else  i = 0;  ///* Buffer remaining input */  md5Memcpy(buffer, inbuf, index, i, inputLen - i);  }  /* md5Final整理和填写输出结果 */  private void md5Final() {  byte[] bits = new byte[8];  int index, padLen;  ///* Save number of bits */  Encode(bits, count, 8);  ///* Pad out to 56 mod 64.  index = (int) (count[0] >>> 3) & 0x3f;  padLen = (index < 56) ? (56 - index) : (120 - index);  md5Update(PADDING, padLen);  ///* Append length (before padding) */  md5Update(bits, 8);  ///* Store state in digest */  Encode(digest, state, 16);  }  /* md5Memcpy是一个内部使用的byte数组的块拷贝函数，从input的inpos开始把len长度的 字节拷贝到output的outpos位置开始 */  private void md5Memcpy(byte[] output, byte[] input, int outpos, int inpos, int len) {  int i;  for (i = 0; i < len; i++)  output[outpos + i] = input[inpos + i];  }  /* md5Transform是MD5核心变换程序，有md5Update调用，block是分块的原始字节 */  private void md5Transform(byte block[]) {  long a = state[0], b = state[1], c = state[2], d = state[3];  long[] x = new long[16];  Decode(x, block, 64);  /* Round 1 */  a = FF(a, b, c, d, x[0], S11, 0xd76aa478L); /* 1 */  d = FF(d, a, b, c, x[1], S12, 0xe8c7b756L); /* 2 */  c = FF(c, d, a, b, x[2], S13, 0x242070dbL); /* 3 */  b = FF(b, c, d, a, x[3], S14, 0xc1bdceeeL); /* 4 */  a = FF(a, b, c, d, x[4], S11, 0xf57c0fafL); /* 5 */  d = FF(d, a, b, c, x[5], S12, 0x4787c62aL); /* 6 */  c = FF(c, d, a, b, x[6], S13, 0xa8304613L); /* 7 */  b = FF(b, c, d, a, x[7], S14, 0xfd469501L); /* 8 */  a = FF(a, b, c, d, x[8], S11, 0x698098d8L); /* 9 */  d = FF(d, a, b, c, x[9], S12, 0x8b44f7afL); /* 10 */  c = FF(c, d, a, b, x[10], S13, 0xffff5bb1L); /* 11 */  b = FF(b, c, d, a, x[11], S14, 0x895cd7beL); /* 12 */  a = FF(a, b, c, d, x[12], S11, 0x6b901122L); /* 13 */  d = FF(d, a, b, c, x[13], S12, 0xfd987193L); /* 14 */  c = FF(c, d, a, b, x[14], S13, 0xa679438eL); /* 15 */  b = FF(b, c, d, a, x[15], S14, 0x49b40821L); /* 16 */  /* Round 2 */  a = GG(a, b, c, d, x[1], S21, 0xf61e2562L); /* 17 */  d = GG(d, a, b, c, x[6], S22, 0xc040b340L); /* 18 */  c = GG(c, d, a, b, x[11], S23, 0x265e5a51L); /* 19 */  b = GG(b, c, d, a, x[0], S24, 0xe9b6c7aaL); /* 20 */  a = GG(a, b, c, d, x[5], S21, 0xd62f105dL); /* 21 */  d = GG(d, a, b, c, x[10], S22, 0x2441453L); /* 22 */  c = GG(c, d, a, b, x[15], S23, 0xd8a1e681L); /* 23 */  b = GG(b, c, d, a, x[4], S24, 0xe7d3fbc8L); /* 24 */  a = GG(a, b, c, d, x[9], S21, 0x21e1cde6L); /* 25 */  d = GG(d, a, b, c, x[14], S22, 0xc33707d6L); /* 26 */  c = GG(c, d, a, b, x[3], S23, 0xf4d50d87L); /* 27 */  b = GG(b, c, d, a, x[8], S24, 0x455a14edL); /* 28 */  a = GG(a, b, c, d, x[13], S21, 0xa9e3e905L); /* 29 */  d = GG(d, a, b, c, x[2], S22, 0xfcefa3f8L); /* 30 */  c = GG(c, d, a, b, x[7], S23, 0x676f02d9L); /* 31 */  b = GG(b, c, d, a, x[12], S24, 0x8d2a4c8aL); /* 32 */  /* Round 3 */  a = HH(a, b, c, d, x[5], S31, 0xfffa3942L); /* 33 */  d = HH(d, a, b, c, x[8], S32, 0x8771f681L); /* 34 */  c = HH(c, d, a, b, x[11], S33, 0x6d9d6122L); /* 35 */  b = HH(b, c, d, a, x[14], S34, 0xfde5380cL); /* 36 */  a = HH(a, b, c, d, x[1], S31, 0xa4beea44L); /* 37 */  d = HH(d, a, b, c, x[4], S32, 0x4bdecfa9L); /* 38 */  c = HH(c, d, a, b, x[7], S33, 0xf6bb4b60L); /* 39 */  b = HH(b, c, d, a, x[10], S34, 0xbebfbc70L); /* 40 */  a = HH(a, b, c, d, x[13], S31, 0x289b7ec6L); /* 41 */  d = HH(d, a, b, c, x[0], S32, 0xeaa127faL); /* 42 */  c = HH(c, d, a, b, x[3], S33, 0xd4ef3085L); /* 43 */  b = HH(b, c, d, a, x[6], S34, 0x4881d05L); /* 44 */  a = HH(a, b, c, d, x[9], S31, 0xd9d4d039L); /* 45 */  d = HH(d, a, b, c, x[12], S32, 0xe6db99e5L); /* 46 */  c = HH(c, d, a, b, x[15], S33, 0x1fa27cf8L); /* 47 */  b = HH(b, c, d, a, x[2], S34, 0xc4ac5665L); /* 48 */  /* Round 4 */  a = II(a, b, c, d, x[0], S41, 0xf4292244L); /* 49 */  d = II(d, a, b, c, x[7], S42, 0x432aff97L); /* 50 */  c = II(c, d, a, b, x[14], S43, 0xab9423a7L); /* 51 */  b = II(b, c, d, a, x[5], S44, 0xfc93a039L); /* 52 */  a = II(a, b, c, d, x[12], S41, 0x655b59c3L); /* 53 */  d = II(d, a, b, c, x[3], S42, 0x8f0ccc92L); /* 54 */  c = II(c, d, a, b, x[10], S43, 0xffeff47dL); /* 55 */  b = II(b, c, d, a, x[1], S44, 0x85845dd1L); /* 56 */  a = II(a, b, c, d, x[8], S41, 0x6fa87e4fL); /* 57 */  d = II(d, a, b, c, x[15], S42, 0xfe2ce6e0L); /* 58 */  c = II(c, d, a, b, x[6], S43, 0xa3014314L); /* 59 */  b = II(b, c, d, a, x[13], S44, 0x4e0811a1L); /* 60 */  a = II(a, b, c, d, x[4], S41, 0xf7537e82L); /* 61 */  d = II(d, a, b, c, x[11], S42, 0xbd3af235L); /* 62 */  c = II(c, d, a, b, x[2], S43, 0x2ad7d2bbL); /* 63 */  b = II(b, c, d, a, x[9], S44, 0xeb86d391L); /* 64 */  state[0] += a;  state[1] += b;  state[2] += c;  state[3] += d;  }  /*Encode把long数组按顺序拆成byte数组，因为java的long类型是64bit的， 只拆低32bit，以适应原始C实现的用途 */  private void Encode(byte[] output, long[] input, int len) {  int i, j;  for (i = 0, j = 0; j < len; i++, j += 4) {  output[j] = (byte) (input[i] & 0xffL);  output[j + 1] = (byte) ((input[i] >>> 8) & 0xffL);  output[j + 2] = (byte) ((input[i] >>> 16) & 0xffL);  output[j + 3] = (byte) ((input[i] >>> 24) & 0xffL);  }  }  /*Decode把byte数组按顺序合成成long数组，因为java的long类型是64bit的， 只合成低32bit，高32bit清零，以适应原始C实现的用途 */  private void Decode(long[] output, byte[] input, int len) {  int i, j;  for (i = 0, j = 0; j < len; i++, j += 4)  output[i] = b2iu(input[j]) | (b2iu(input[j + 1]) << 8) | (b2iu(input[j + 2]) << 16)  | (b2iu(input[j + 3]) << 24);  return;  }  /* b2iu是我写的一个把byte按照不考虑正负号的原则的＂升位＂程序，因为java没有unsigned运算 */  public static long b2iu(byte b) {  return b < 0 ? b & 0x7F + 128 : b;  }  /*byteHEX()，用来把一个byte类型的数转换成十六进制的ASCII表示， 因为java中的byte的toString无法实现这一点，我们又没有C语言中的 sprintf(outbuf,"%02X",ib) */  public static String byteHEX(byte ib) {  char[] Digit = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };  char[] ob = new char[2];  ob[0] = Digit[(ib >>> 4) & 0X0F];  ob[1] = Digit[ib & 0X0F];  String s = new String(ob);  return s;  }  public static void main(String args[]) {  MD5 m = new MD5();  if (Array.getLength(args) == 0) { //如果没有参数，执行标准的Test Suite  System.out.println("MD5 Test suite:");  System.out.println("MD5(\"\"):" + m.getMD5ofStr(""));  System.out.println("MD5(\"a\"):" + m.getMD5ofStr("a"));  System.out.println("MD5(\"abc\"):" + m.getMD5ofStr("abc"));  System.out.println("MD5(\"11\"):" + m.getMD5ofStr("11"));  System.out.println("MD5(\"123\"):" + m.getMD5ofStr("123"));  System.out.println("MD5(\"message digest\"):" + m.getMD5ofStr("message digest"));  System.out.println("MD5(\"abcdefghijklmnopqrstuvwxyz\"):" + m.getMD5ofStr("abcdefghijklmnopqrstuvwxyz"));  System.out.println("MD5(\"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789\"):"  + m.getMD5ofStr("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"));  } else  System.out.println("MD5(" + args[0] + ")=" + m.getMD5ofStr(args[0]));  }  }