時(shí)間：2017年4月10日星期一
說(shuō)明：本文部分內(nèi)容均來(lái)自慕課網(wǎng)。@慕課網(wǎng)：http://www.imooc.com
教學(xué)示例源碼：https://github.com/zccodere/s...
個(gè)人學(xué)習(xí)源碼：https://github.com/zccodere/s...

消息摘要算法

MD（Message Digest）
SHA（Secure Hash Algorithm）
MAC（Message Authentication Code）
驗(yàn)證數(shù)據(jù)完整性
數(shù)字簽名核心算法

消息摘要算法：MD

MD5
MD家族（128位摘要信息）
--MD2、MD4
特點(diǎn)

算法實(shí)現(xiàn)：

代碼演示：

package com.myimooc.security.md;

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

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

/**
 * MD消息摘要加密演示
 * Created by ZC on 2017/4/10.
 */
public class DemoMD {

    /** 待加密字符串 */
    private static String src="imooc security md";

    public static void main(String[] args){
        jdkMD5();
        jdkMD2();
        bcMD4();
        bcMD5();
        ccMD5();
        ccMD2();
    }

    /**
     * 通過(guò) jdk 實(shí)現(xiàn)MD5加密
     */
    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();
        }
    }

    /**
     * 通過(guò) jdk 實(shí)現(xiàn)MD2加密
     */
    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();
        }
    }

    /**
     * 通過(guò) bouncy castle 實(shí)現(xiàn)MD5加密
     */
    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));
    }

    /**
     * 通過(guò) bouncy castle 實(shí)現(xiàn)MD4加密
     */
    public static void bcMD4(){
        try {
            Security.addProvider(new BouncyCastleProvider());
            MessageDigest md = MessageDigest.getInstance("MD4");
            byte[] md5Bytes = md.digest(src.getBytes());
            System.out.println("BC MD4:"+org.bouncycastle.util.encoders.Hex.toHexString(md5Bytes));
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
    }

    /**
     * 通過(guò) commons codec 實(shí)現(xiàn)MD5加密
     */
    public static void ccMD5(){
        System.out.println("CC MD5:"+DigestUtils.md5Hex(src.getBytes()));
    }

    /**
     * 通過(guò) commons codec 實(shí)現(xiàn)MD5加密
     */
    public static void ccMD2(){
        System.out.println("CC MD2:"+DigestUtils.md2Hex(src.getBytes()));
    }

}

流程演示：

消息摘要算法：SHA

安全散列算法
固定長(zhǎng)度摘要信息
SHA-1、SHA-2（SHA-224、SHA-256、SHA-384、SHA-512）

算法實(shí)現(xiàn)：

代碼演示：

package com.myimooc.security.sha;

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;

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

/**
 * SHA消息摘要加密演示
 * Created by ZC on 2017/4/10.
 */
public class DemoSHA {

    /** 待加密字符串 */
    private static String src="imooc security sha";

    public static void main(String[] args){
        jdkSHA1();
        bcSHA1();
        bcSHA224();
        bcSHA224_2();
        ccSHA1();
    }

    /**
     * 通過(guò) JDK 實(shí)現(xiàn)SHA-1 加密
     */
    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();
        }
    }

    /**
     * 通過(guò) bouncy castle 實(shí)現(xiàn)SHA-1 加密
     */
    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));
    }

    /**
     * 通過(guò) bouncy castle 實(shí)現(xiàn)SHA-224 加密
     */
    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));
    }

    /** 通過(guò) provider 實(shí)現(xiàn)SHA224加密 */
    public static void bcSHA224_2(){
        Security.addProvider(new BouncyCastleProvider());
        try {
            MessageDigest md = MessageDigest.getInstance("SHA224");
            byte[] sha224Bytes = md.digest(src.getBytes());
            System.out.println("sha-224:"+ org.bouncycastle.util.encoders.Hex.toHexString(sha224Bytes));
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
    }

    /** 通過(guò) commons.codec 實(shí)現(xiàn)SHA-1加密 */
    public static void ccSHA1(){
        System.out.println("cc sha1-1:"+DigestUtils.sha1Hex(src.getBytes()));
        System.out.println("cc sha1-2:"+DigestUtils.sha1Hex(src));
    }

}

流程演示：

應(yīng)用例子：

MAC（Message Authentication Code）
HMAC（keyed-Hash Message Authentication Code）

    --含有密鑰的散列函數(shù)算法
融合MD、SHA
    --MD系列：HmacMD2、HmacMD4、HmacMD5
應(yīng)用如SecureCRT

算法實(shí)現(xiàn)：

代碼演示：

package com.myimooc.security.mac;

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;

import javax.crypto.KeyGenerator;
import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.security.NoSuchAlgorithmException;

/**
 * MAC消息摘要加密演示
 * Created by ZC on 2017/4/11.
 */
public class DemoMac {

    /** 待加密字符串 */
    private static String src="imooc security mac";

    public static void main(String[] args){
        jdkHmacDM5();
        bcHmacMD5();
    }

    /** jdk實(shí)現(xiàn)hmac MD5摘要算法 */
    public static void jdkHmacDM5(){
        try {
            // 初始化 KeyGenerator
            KeyGenerator keyGenerator = KeyGenerator.getInstance("HmacMD5");
            // 產(chǎn)生密鑰
            SecretKey secretKey = keyGenerator.generateKey();
            // 獲得密鑰
            //byte[] key = secretKey.getEncoded();

            // 自定義密鑰
            byte[] key = Hex.decodeHex(new char[]{"a","a","a","a","a","a","a","a","a","a"});

            // 還原密鑰
            SecretKey restoreSecretKey = new SecretKeySpec(key,"HmacMD5");
            // 實(shí)例化 MAC
            Mac mac = Mac.getInstance(restoreSecretKey.getAlgorithm());
            // 初始化 MAC
            mac.init(restoreSecretKey);
            // 執(zhí)行摘要
            byte[] hmacMD5Bytes = mac.doFinal(src.getBytes());
            System.out.println("jdk hmacMD5:"+ Hex.encodeHexString(hmacMD5Bytes));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /** bouncycastle.crypto實(shí)現(xiàn)hmacMD5加密 */
    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);
        // 執(zhí)行摘要
        byte[] hmacMD5Bytes = new byte[hmac.getMacSize()];
        hmac.doFinal(hmacMD5Bytes,0);

        System.out.println("bc hmacMD5:"+ org.bouncycastle.util.encoders.Hex.toHexString(hmacMD5Bytes));
    }

}

流程演示：

消息摘要算法：其它

RipeMD
Tiger
Whirlpool
GOST3411
Bouncy Castle實(shí)現(xiàn)