Java安全—Java实现消息摘要算法加密

一.概述

        我们打开Apache的官网的如下页面，可以看到md5，点击md5的超链接，在新打开的页面将看到一串字符串，即是MD5的消息摘要。

        消息摘要算法有：MD（Message Digest）、SHA(Secure Hash Algorithm)、MAC（Message Authentication Code），它们的作用是验证数据完整性，是数字签名核心算法。

 

二.消息摘要算法MD

        MD家族（128位摘要信息），除MD5外，还有MD2、MD4。

        BC的算法对JDK算法的补充;CC的MD算法的底层实现其实就是JDK提供的，方便开发者使用。

package com.bijian.study;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.Security;

import org.apache.commons.codec.binary.Hex;
import org.apache.commons.codec.digest.DigestUtils;
import org.bouncycastle.crypto.Digest;
import org.bouncycastle.crypto.digests.MD4Digest;
import org.bouncycastle.crypto.digests.MD5Digest;
import org.bouncycastle.jce.provider.BouncyCastleProvider;

public class BJMD5 {

	private static String src = "bj security md";
	
	public static void main(String[] args) {
		jdkMD5();
		jdkMD2();
		bcMD5();
		bcMD4();
		bcMD4_2();
		getProviderTest();
		ccMD5();
		ccMD2();
	}
	
	public static void jdkMD5() {
		try {
			MessageDigest md = MessageDigest.getInstance("MD5");
			byte[] md5Bytes = md.digest(src.getBytes());
			System.out.println("JDK MD5:" + Hex.encodeHexString(md5Bytes));
		}catch(NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
	}
	
	public static void jdkMD2() {
		try {
			MessageDigest md = MessageDigest.getInstance("MD2");
			byte[] md2Bytes = md.digest(src.getBytes());
			System.out.println("JDK MD2:" + Hex.encodeHexString(md2Bytes));
		}catch(NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
	}
	
	public static void bcMD5() {
		Digest digest = new MD5Digest();
		digest.update(src.getBytes(), 0, src.getBytes().length);
		byte[] md5Bytes = new byte[digest.getDigestSize()];
		digest.doFinal(md5Bytes, 0);
		System.out.println("BC MD5:" + org.bouncycastle.util.encoders.Hex.toHexString(md5Bytes));
	}
	
	public static void bcMD4() {
		Digest digest = new MD4Digest();
		digest.update(src.getBytes(), 0, src.getBytes().length);
		byte[] md4Bytes = new byte[digest.getDigestSize()];
		digest.doFinal(md4Bytes, 0);
		System.out.println("BC MD4:" + org.bouncycastle.util.encoders.Hex.toHexString(md4Bytes));
	}
	
	//通过Security.addProvider方式给JDK动态添加Provider
	public static void bcMD4_2() {
		try {
			Security.addProvider(new BouncyCastleProvider());
			MessageDigest md = MessageDigest.getInstance("MD4");
			System.out.println(md.getProvider());//BC version 1.49
			byte[] md4Bytes = md.digest(src.getBytes());
			System.out.println("BC MD4:" + Hex.encodeHexString(md4Bytes));
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
	}
	
	//如果设置了BouncyCastleProvider,再去获得相应算法时，得到的还是JDK的
	public static void getProviderTest() {
		try {
			Security.addProvider(new BouncyCastleProvider());
			MessageDigest md = MessageDigest.getInstance("MD5");
			System.out.println(md.getProvider());//SUN version 1.6
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
	}
	
	public static void ccMD5() {
		System.out.println("CC MD5:" + DigestUtils.md5Hex(src.getBytes()));
	}
	
	public static void ccMD2() {
		System.out.println("CC MD2:" + DigestUtils.md2Hex(src.getBytes()));
	}
}

运行结果：

JDK MD5:0cf7225221a46eb7fb10c46c4e415344
JDK MD2:d4d6c6a7bd4aaf821453ce1df02c597c
BC MD5:0cf7225221a46eb7fb10c46c4e415344
BC MD4:e0950c38aedccf757dcb07424425be44
BC version 1.49
BC MD4:e0950c38aedccf757dcb07424425be44
SUN version 1.6
CC MD5:0cf7225221a46eb7fb10c46c4e415344
CC MD2:d4d6c6a7bd4aaf821453ce1df02c597c

        应用：在用户注册认证时，对密码进行MD摘要处理后保存。

三.消息摘要算法SHA

         SHA算法是一个安全散列算法，是固定长度摘要信息。包括SHA-1、SHA-2(SHA-224、SHA-256、SHA-384、SHA-512)算法。

package com.bijian.study;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.Security;

import org.apache.commons.codec.binary.Hex;
import org.apache.commons.codec.digest.DigestUtils;
import org.bouncycastle.crypto.Digest;
import org.bouncycastle.crypto.digests.SHA1Digest;
import org.bouncycastle.crypto.digests.SHA224Digest;
import org.bouncycastle.jce.provider.BouncyCastleProvider;

public class BJSHA {

	private static String src = "bj security sha";
	
	public static void main(String[] args) {
		jdkSHA1();
		bcSHA1();
		bcSHA224();
		bcSHA224_2();
		ccSHA1();
	}
	
	public static void jdkSHA1() {

		try {
			MessageDigest md = MessageDigest.getInstance("SHA");
			md.update(src.getBytes());
			System.out.println("jdk sha-1:" + Hex.encodeHexString(md.digest()));
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
	}
	
	public static void bcSHA1() {
		Digest digest = new SHA1Digest();
		digest.update(src.getBytes(), 0, src.getBytes().length);
		byte[] sha1Bytes = new byte[digest.getDigestSize()];
		digest.doFinal(sha1Bytes, 0);
		System.out.println("bc sha-1:" + org.bouncycastle.util.encoders.Hex.toHexString(sha1Bytes));
	}
	
	public static void bcSHA224() {
		Digest digest = new SHA224Digest();
		digest.update(src.getBytes(), 0, src.getBytes().length);
		byte[] sha224Bytes = new byte[digest.getDigestSize()];
		digest.doFinal(sha224Bytes, 0);
		System.out.println("bc sha-224:" + org.bouncycastle.util.encoders.Hex.toHexString(sha224Bytes));
	}
	
	//Provider方式实现SHA224
	public static void bcSHA224_2() {
		try {
			Security.addProvider(new BouncyCastleProvider());
			MessageDigest md = MessageDigest.getInstance("SHA224");
			System.out.println(md.getProvider());//BC version 1.49
			byte[] sha224Bytes = md.digest(src.getBytes());
			System.out.println("bc sha-224_2:" + Hex.encodeHexString(sha224Bytes));
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
	}
	
	public static void ccSHA1() {
		System.out.println("cc sha1-1:" + DigestUtils.sha1Hex(src.getBytes()));
		System.out.println("cc sha1-2:" + DigestUtils.sha1Hex(src));
	}
}

运行结果：

jdk sha-1:8195da0382300aac158cfc55c61fb58478a0ebe2
bc sha-1:8195da0382300aac158cfc55c61fb58478a0ebe2
bc sha-224:34533e26cfa2b14e6f21d731148bb589233bcc2a10136fa3b4a5ec97
BC version 1.49
bc sha-224_2:34533e26cfa2b14e6f21d731148bb589233bcc2a10136fa3b4a5ec97
cc sha1-1:8195da0382300aac158cfc55c61fb58478a0ebe2
cc sha1-2:8195da0382300aac158cfc55c61fb58478a0ebe2

        打开Firxfox，我们可以看到SHA的应用。

        消息摘要算法经典用法：

        消息鉴别是指在接收方将原始信息进行摘要，然后与接收到的摘要信息进行比对。当然，在发送消息中比较常用的做法是：a.加入约定Key；b.增加时间戳；c.排序。

        如：http://***?msg=12Had47mj&timestamp=1325252526，其中msg：原始消息+key+时间戳。具体也可以参考腾讯的Open API。

 

四.消息摘要算法MAC

        MAC：Message Authentication Code，HMAC：keyed-Hash Message Authentication Code，含有密钥的散列函数算法，融合MD、SHA。

        MD系列：HmacMD2、HmacMD4、HmacMD5。

        SHA系列：HmacSHA1、HmacSHA224、HmacSHA256、HmacSHA384、HmacSHA512。

        应用如SecureCRT。

package com.bijian.study;

import java.security.InvalidKeyException;
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.DecoderException;
import org.apache.commons.codec.binary.Hex;
import org.bouncycastle.crypto.digests.MD5Digest;
import org.bouncycastle.crypto.macs.HMac;
import org.bouncycastle.crypto.params.KeyParameter;

public class BJHmac {

	private static String src = "bj security hmac";
	
	public static void main(String[] args) {
		jdkHmacMD5();
		bcHmacMD5();
	}
	
	//JDK的Hmac的MD5算法
	public static void jdkHmacMD5() {
		try {
			//初始化KeyGenerator
			KeyGenerator keyGenerator = KeyGenerator.getInstance("HmacMD5");
			SecretKey secretKey = keyGenerator.generateKey();//产生密钥
//			byte[] key = secretKey.getEncoded();//获得密钥
			
			byte[] key = Hex.decodeHex(new char[]{'a','a','a','a','a','a','a','a','a','a'});
			
			SecretKey restoreSecreKey = new SecretKeySpec(key, "HmacMD5");//还原密钥
			Mac mac = Mac.getInstance(restoreSecreKey.getAlgorithm());//实例化MAC
			mac.init(restoreSecreKey);
			byte[] hmacMD5Bytes = mac.doFinal(src.getBytes());
			System.out.println("jdk hmacMD5:" + Hex.encodeHexString(hmacMD5Bytes));
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		} catch (InvalidKeyException e) {
			e.printStackTrace();
		} catch (DecoderException e) {
			e.printStackTrace();
		}
	}
	
	//BC的Hmac的MD5算法
	public static void bcHmacMD5() {
		HMac hmac = new HMac(new MD5Digest());
		hmac.init(new KeyParameter(org.bouncycastle.util.encoders.Hex.decode("aaaaaaaaaa")));
		hmac.update(src.getBytes(), 0, src.getBytes().length);
		
		byte[] hmacMD5Bytes = new byte[hmac.getMacSize()];//执行摘要
		hmac.doFinal(hmacMD5Bytes, 0);
		
		System.out.println("bc hmacMD5:" + Hex.encodeHexString(hmacMD5Bytes));
	}
}

运行结果：

jdk hmacMD5:cc31626a65895732de1bc6b53cd89dca
bc hmacMD5:cc31626a65895732de1bc6b53cd89dca

算法的典型应用：

 

五.其它消息摘要算法

        1.RipeMD

        2.Tiger

        3.Whirlpool

        4.GOST3411

        以上几类都是Bouncy Castle实现

 

学习视频地址：http://www.imooc.com/learn/286