一、简述
mac（Message Authentication Code。消息认证码算法）是含有密钥散列函数算法。兼容了MD和SHA算法的特性，并在此基础上加上了密钥。因此MAC算法也常常被称作HMAC算法。关于hmac算法的详情能够參看RFC 2104(http://www.ietf.org/rfc/rfc2104.txt)。这里包括了HmacMD5算法的C语言实现。
这里须要说明的是经过mac算法得到的摘要值也能够使用十六进制编码表示。其摘要值得长度与实现算法的摘要值长度同样。比如 HmacSHA算法得到的摘要长度就是SHA1算法得到的摘要长度，都是160位二进制数，换算成十六进制的编码为40位。
二、模型分析
甲乙两方进行数据交换能够採取例如以下流程完毕
1、甲方向乙方发布摘要算法（就是指定要使用的摘要算法名）
2、甲乙两方依照约定构造密钥，两方拥有同样的密钥（通常是一方构造密钥后通知另外一方，此过程不须要通过程序实现，就是两方约定个字符串，可是这个字符串可不是随便设定的，也是通过相关算法获取的）
3、甲方使用密钥对消息做摘要处理，然后将消息和生成的摘要消息一同发送给乙方
4、乙方收到消息后，使用甲方已经发布的摘要算法+约定好的密钥 对收到的消息进行摘要处理。然后比对自己的摘要消息和甲方发过来的摘要消息。
甄别消息是否是甲方发送过来的
三、MAC系列算法支持表
| 算法 | 摘要长度 | 备注 |
| HmacMD5 | 128 | BouncyCastle实现 |
| HmacSHA1 | 160 | BouncyCastle实现 |
| HmacSHA256 | 256 | BouncyCastle实现 |
| HmacSHA384 | 384 | BouncyCastle实现 |
| HmacSHA512 | 512 | JAVA6实现 |
| HmacMD2 | 128 | BouncyCastle实现 |
| HmacMD4 | 128 | BouncyCastle实现 |
| HmacSHA224 | 224 | BouncyCastle实现 |
package com.main;
import java.security.Security;
import javax.crypto.KeyGenerator;
import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.util.encoders.Hex;
/**
* MAC消息摘要组件
* @author kongqz
* */
public class HAMC {
///////////////////////////HmacMD5///////////////////////////////
/**
* 初始化HmacMD5的密钥
* @return byte[] 密钥
*
* */
public static byte[] initHmacMD5Key() throws Exception{
//增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//初始化KeyGenerator
KeyGenerator keyGenerator=KeyGenerator.getInstance("HmacMD5");
//产生密钥
SecretKey secretKey=keyGenerator.generateKey();
//获取密钥
return secretKey.getEncoded();
}
/**
* HmacMD5消息摘要
* @param data 待做摘要处理的数据
* @param key 密钥
* @return byte[] 消息摘要
* */
public static byte[] encodeHmacMD5(byte[] data,byte[] key) throws Exception{
//增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//还原密钥，由于密钥是以byte形式为消息传递算法所拥有
SecretKey secretKey=new SecretKeySpec(key,"HmacMD5");
//实例化Mac
Mac mac=Mac.getInstance(secretKey.getAlgorithm());
//初始化Mac
mac.init(secretKey);
//运行消息摘要处理
return mac.doFinal(data);
}
/**
* HmacMD2Hex消息摘要
* @param data 待做消息摘要处理的数据
* @param String 密钥
* @return byte[] 消息摘要
* */
public static String encodeHmacMD5Hex(byte[] data,byte[] key) throws Exception{
//运行消息摘要处理
byte[] b=encodeHmacMD5(data,key);
//做十六进制转换
return new String(Hex.encode(b));
} ///////////////////////////////HmacSHA1//////////////////////////////////
/**
* 初始化HmacSHA1的密钥
* @return byte[] 密钥
*
* */
public static byte[] initHmacSHAKey() throws Exception{
//初始化KeyGenerator
KeyGenerator keyGenerator=KeyGenerator.getInstance("HmacSHA1");
//产生密钥
SecretKey secretKey=keyGenerator.generateKey();
//获取密钥
return secretKey.getEncoded();
}
/**
* HmacSHA1消息摘要
* @param data 待做摘要处理的数据
* @param key 密钥
* @return byte[] 消息摘要
* */
public static byte[] encodeHmacSHA(byte[] data,byte[] key) throws Exception{
//还原密钥，由于密钥是以byte形式为消息传递算法所拥有
SecretKey secretKey=new SecretKeySpec(key,"HmacSHA1");
//实例化Mac
Mac mac=Mac.getInstance(secretKey.getAlgorithm());
//初始化Mac
mac.init(secretKey);
//运行消息摘要处理
return mac.doFinal(data);
} ///////////////////////////////HmacSHA256//////////////////////////////////
/**
* 初始化HmacSHA256的密钥
* @return byte[] 密钥
*
* */
public static byte[] initHmacSHA256Key() throws Exception{
Security.addProvider(new BouncyCastleProvider());
//初始化KeyGenerator
KeyGenerator keyGenerator=KeyGenerator.getInstance("HmacSHA256");
//产生密钥
SecretKey secretKey=keyGenerator.generateKey();
//获取密钥
return secretKey.getEncoded();
}
/**
* HmacSHA256消息摘要
* @param data 待做摘要处理的数据
* @param key 密钥
* @return byte[] 消息摘要
* */
public static byte[] encodeHmacSHA256(byte[] data,byte[] key) throws Exception{
//增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//还原密钥，由于密钥是以byte形式为消息传递算法所拥有
SecretKey secretKey=new SecretKeySpec(key,"HmacSHA256");
//实例化Mac
Mac mac=Mac.getInstance(secretKey.getAlgorithm());
//初始化Mac
mac.init(secretKey);
//运行消息摘要处理
return mac.doFinal(data);
} ///////////////////////////////HmacSHA384//////////////////////////////////
/**
* 初始化HmacSHA384的密钥
* @return byte[] 密钥
*
* */
public static byte[] initHmacSHA384Key() throws Exception{
Security.addProvider(new BouncyCastleProvider());
//初始化KeyGenerator
KeyGenerator keyGenerator=KeyGenerator.getInstance("HmacSHA384");
//产生密钥
SecretKey secretKey=keyGenerator.generateKey();
//获取密钥
return secretKey.getEncoded();
}
/**
* HmacSHA384消息摘要
* @param data 待做摘要处理的数据
* @param key 密钥
* @return byte[] 消息摘要
* */
public static byte[] encodeHmacSHA384(byte[] data,byte[] key) throws Exception{
Security.addProvider(new BouncyCastleProvider());
//还原密钥，由于密钥是以byte形式为消息传递算法所拥有
SecretKey secretKey=new SecretKeySpec(key,"HmacSHA384");
//实例化Mac
Mac mac=Mac.getInstance(secretKey.getAlgorithm());
//初始化Mac
mac.init(secretKey);
//运行消息摘要处理
return mac.doFinal(data);
} ///////////////////////////////HmacSHA512//////////////////////////////////
/**
* 初始化HmacSHA512的密钥
* @return byte[] 密钥
*
* */
public static byte[] initHmacSHA512Key() throws Exception{
//初始化KeyGenerator
KeyGenerator keyGenerator=KeyGenerator.getInstance("HmacSHA512");
//产生密钥
SecretKey secretKey=keyGenerator.generateKey();
//获取密钥
return secretKey.getEncoded();
}
/**
* HmacSHA512消息摘要
* @param data 待做摘要处理的数据
* @param key 密钥
* @return byte[] 消息摘要
* */
public static byte[] encodeHmacSHA512(byte[] data,byte[] key) throws Exception{
//还原密钥。由于密钥是以byte形式为消息传递算法所拥有
SecretKey secretKey=new SecretKeySpec(key,"HmacSHA512");
//实例化Mac
Mac mac=Mac.getInstance(secretKey.getAlgorithm());
//初始化Mac
mac.init(secretKey);
//运行消息摘要处理
return mac.doFinal(data);
}
///////////////////////////////HmacMD2-BouncyCastle才支持的实现//////////////////////////////////
/**
* 初始化HmacMD2的密钥
* @return byte[] 密钥
* */
public static byte[] initHmacMD2Key() throws Exception{ //增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//初始化KeyGenerator
KeyGenerator keyGenerator=KeyGenerator.getInstance("HmacMD2");
//产生密钥
SecretKey secretKey=keyGenerator.generateKey();
//获取密钥
return secretKey.getEncoded();
}
/**
* HmacMD2消息摘要
* @param data 待做摘要处理的数据
* @param key 密钥
* @return byte[] 消息摘要
* */
public static byte[] encodeHmacMD2(byte[] data,byte[] key) throws Exception{
//增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//还原密钥，由于密钥是以byte形式为消息传递算法所拥有
SecretKey secretKey=new SecretKeySpec(key,"HmacMD2");
//实例化Mac
Mac mac=Mac.getInstance(secretKey.getAlgorithm());
//初始化Mac
mac.init(secretKey);
//运行消息摘要处理
return mac.doFinal(data);
}
/**
* HmacMD2Hex消息摘要
* @param data 待做消息摘要处理的数据
* @param String 密钥
* @return byte[] 消息摘要
* */
public static String encodeHmacMD2Hex(byte[] data,byte[] key) throws Exception{
//运行消息摘要处理
byte[] b=encodeHmacMD2(data,key);
//做十六进制转换
return new String(Hex.encode(b));
} ///////////////////////////////HmacMD4-BouncyCastle才支持的实现//////////////////////////////////
/**
* 初始化HmacMD2的密钥
* @return byte[] 密钥
* */
public static byte[] initHmacMD4Key() throws Exception{ //增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//初始化KeyGenerator
KeyGenerator keyGenerator=KeyGenerator.getInstance("HmacMD4");
//产生密钥
SecretKey secretKey=keyGenerator.generateKey();
//获取密钥
return secretKey.getEncoded();
}
/**
* HmacMD4消息摘要
* @param data 待做摘要处理的数据
* @param key 密钥
* @return byte[] 消息摘要
* */
public static byte[] encodeHmacMD4(byte[] data,byte[] key) throws Exception{
//增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//还原密钥，由于密钥是以byte形式为消息传递算法所拥有
SecretKey secretKey=new SecretKeySpec(key,"HmacMD4");
//实例化Mac
Mac mac=Mac.getInstance(secretKey.getAlgorithm());
//初始化Mac
mac.init(secretKey);
//运行消息摘要处理
return mac.doFinal(data);
}
/**
* HmacMD4Hex消息摘要
* @param data 待做消息摘要处理的数据
* @param String 密钥
* @return byte[] 消息摘要
* */
public static String encodeHmacMD4Hex(byte[] data,byte[] key) throws Exception{
//运行消息摘要处理
byte[] b=encodeHmacMD4(data,key);
//做十六进制转换
return new String(Hex.encode(b));
}
///////////////////////////////HmacSHA224-BouncyCastle才支持的实现//////////////////////////////////
/**
* 初始化HmacSHA224的密钥
* @return byte[] 密钥
* */
public static byte[] initHmacSHA224Key() throws Exception{ //增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//初始化KeyGenerator
KeyGenerator keyGenerator=KeyGenerator.getInstance("HmacSHA224");
//产生密钥
SecretKey secretKey=keyGenerator.generateKey();
//获取密钥
return secretKey.getEncoded();
}
/**
* HmacSHA224消息摘要
* @param data 待做摘要处理的数据
* @param key 密钥
* @return byte[] 消息摘要
* */
public static byte[] encodeHmacSHA224(byte[] data,byte[] key) throws Exception{
//增加BouncyCastleProvider的支持
Security.addProvider(new BouncyCastleProvider());
//还原密钥，由于密钥是以byte形式为消息传递算法所拥有
SecretKey secretKey=new SecretKeySpec(key,"HmacSHA224");
//实例化Mac
Mac mac=Mac.getInstance(secretKey.getAlgorithm());
//初始化Mac
mac.init(secretKey);
//运行消息摘要处理
return mac.doFinal(data);
}
/**
* HmacSHA224Hex消息摘要
* @param data 待做消息摘要处理的数据
* @param String 密钥
* @return byte[] 消息摘要
* */
public static String encodeHmacSHA224Hex(byte[] data,byte[] key) throws Exception{
//运行消息摘要处理
byte[] b=encodeHmacSHA224(data,key);
//做十六进制转换
return new String(Hex.encode(b));
}
/**
* 进行相关的摘要算法的处理展示
* @throws Exception
* **/
public static void main(String[] args) throws Exception {
String str="123000000000090989999999999999999999999999999999999999999999999999999999999999999999111" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"23000000000090989999999999999999999999999999999999999999999999999999999999999999999" +
"230000000000909899999999999999999999999999999999999999999999999999999999999999999991";
//初始化密钥
byte[] key1=HAMC.initHmacMD5Key();
//获取摘要信息
byte[] data1=HAMC.encodeHmacMD5(str.getBytes(), key1);
String datahex1=new String(Hex.encode(data1)); System.out.println("原文："+str);
System.out.println(); System.out.println("Bouncycastle HmacMD5的密钥内容和长度:"+key1.toString()+"--"+key1.length);
System.out.println("Bouncycastle HmacMD5算法摘要："+data1.toString());
System.out.println("Bouncycastle HmacMD5算法摘要HEX："+datahex1.toString());
System.out.println(); //初始化密钥
byte[] key2=HAMC.initHmacSHA256Key();
//获取摘要信息
byte[] data2=HAMC.encodeHmacSHA256(str.getBytes(), key2);
String datahex2=new String(Hex.encode(data2));
System.out.println("Bouncycastle HmacSHA256的密钥:"+key2.toString());
System.out.println("Bouncycastle HmacSHA256算法摘要："+data2.toString());
System.out.println("Bouncycastle HmacSHA256算法摘要HEX："+datahex2);
System.out.println(); //初始化密钥
byte[] key3=HAMC.initHmacSHAKey();
//获取摘要信息
byte[] data3=HAMC.encodeHmacSHA(str.getBytes(), key3);
String datahex3=new String(Hex.encode(data3));
System.out.println("Bouncycastle HmacSHA1的密钥:"+key3.toString());
System.out.println("Bouncycastle HmacSHA1算法摘要："+data3.toString());
System.out.println("Bouncycastle HmacSHA1算法摘要HEX："+datahex3);
System.out.println(); //初始化密钥
byte[] key4=HAMC.initHmacSHA384Key(); //获取摘要信息
byte[] data4=HAMC.encodeHmacSHA384(str.getBytes(), key4);
String datahex4=new String(Hex.encode(data4));
System.out.println("Bouncycastle HmacSHA384的密钥:"+key4.toString());
System.out.println("Bouncycastle HmacSHA384算法摘要："+data4.toString());
System.out.println("Bouncycastle HmacSHA384算法摘要HEX："+datahex4);
System.out.println(); //初始化密钥
byte[] key5=HAMC.initHmacSHA512Key();
//获取摘要信息
byte[] data5=HAMC.encodeHmacSHA512(str.getBytes(), key5);
System.out.println("HmacSHA512的密钥:"+key5.toString());
System.out.println("HmacSHA512算法摘要："+data5.toString());
System.out.println(); System.out.println("================下面的算法支持是bouncycastle支持的算法，sun java6不支持=======================");
//初始化密钥
byte[] key6=HAMC.initHmacMD2Key();
//获取摘要信息
byte[] data6=HAMC.encodeHmacMD2(str.getBytes(), key6);
String datahex6=HAMC.encodeHmacMD2Hex(str.getBytes(), key6);
System.out.println("Bouncycastle HmacMD2的密钥:"+key6.toString());
System.out.println("Bouncycastle HmacMD2算法摘要："+data6.toString());
System.out.println("Bouncycastle HmacMD2Hex算法摘要："+datahex6.toString());
System.out.println(); //初始化密钥
byte[] key7=HAMC.initHmacMD4Key();
//获取摘要信息
byte[] data7=HAMC.encodeHmacMD4(str.getBytes(), key7);
String datahex7=HAMC.encodeHmacMD4Hex(str.getBytes(), key7);
System.out.println("Bouncycastle HmacMD4的密钥:"+key7.toString());
System.out.println("Bouncycastle HmacMD4算法摘要："+data7.toString());
System.out.println("Bouncycastle HmacMD4Hex算法摘要："+datahex7.toString());
System.out.println(); //初始化密钥
byte[] key8=HAMC.initHmacSHA224Key();
//获取摘要信息
byte[] data8=HAMC.encodeHmacSHA224(str.getBytes(), key8);
String datahex8=HAMC.encodeHmacSHA224Hex(str.getBytes(), key8);
System.out.println("Bouncycastle HmacSHA224的密钥:"+key8.toString());
System.out.println("Bouncycastle HmacSHA224算法摘要："+data8.toString());
System.out.println("Bouncycastle HmacSHA224算法摘要："+datahex8.toString());
System.out.println();
}
}
运行结果是：
原文：123000000000090989999999999999999999999999999999999999999999999999999999999999999999111230000000000909899999999999999999999999999999999999999999999999999999999999999999992300000000009098999999999999999999999999999999999999999999999999999999999999999999923000000000090989999999999999999999999999999999999999999999999999999999999999999999230000000000909899999999999999999999999999999999999999999999999999999999999999999992300000000009098999999999999999999999999999999999999999999999999999999999999999999923000000000090989999999999999999999999999999999999999999999999999999999999999999999230000000000909899999999999999999999999999999999999999999999999999999999999999999992300000000009098999999999999999999999999999999999999999999999999999999999999999999923000000000090989999999999999999999999999999999999999999999999999999999999999999999230000000000909899999999999999999999999999999999999999999999999999999999999999999992300000000009098999999999999999999999999999999999999999999999999999999999999999999923000000000090989999999999999999999999999999999999999999999999999999999999999999999230000000000909899999999999999999999999999999999999999999999999999999999999999999992300000000009098999999999999999999999999999999999999999999999999999999999999999999923000000000090989999999999999999999999999999999999999999999999999999999999999999999230000000000909899999999999999999999999999999999999999999999999999999999999999999991 Bouncycastle HmacMD5的密钥内容和长度:[B@2fb212f0--64
Bouncycastle HmacMD5算法摘要：[B@53f96306
Bouncycastle HmacMD5算法摘要HEX：771093e83aeb659d125100fa465bd34e Bouncycastle HmacSHA256的密钥:[B@450b9338
Bouncycastle HmacSHA256算法摘要：[B@7aee64f1
Bouncycastle HmacSHA256算法摘要HEX：2d211a42cb3fb68cd36255f9af4ef614eea6c8b93634183d333bf3e6e0b79d87 Bouncycastle HmacSHA1的密钥:[B@592bf469
Bouncycastle HmacSHA1算法摘要：[B@54bb473b
Bouncycastle HmacSHA1算法摘要HEX：c07963727b485cf6579d103a822382f3159bc6ee Bouncycastle HmacSHA384的密钥:[B@1527171d
Bouncycastle HmacSHA384算法摘要：[B@395e7bc4
Bouncycastle HmacSHA384算法摘要HEX：cae75e5a2ce20d18bf0862215896f8dbe060ac10806925fa5d2bb15cc983543a1d0e53743f1e84ee53ad7db128547cde HmacSHA512的密钥:[B@5689a400
HmacSHA512算法摘要：[B@666e2862 ================下面的算法支持是bouncycastle支持的算法。sun java6不支持=======================
Bouncycastle HmacMD2的密钥:[B@fca1ca
Bouncycastle HmacMD2算法摘要：[B@49e1d547
Bouncycastle HmacMD2Hex算法摘要：2fad1ddef0a1d4d9e7bed45c4b714ae5 Bouncycastle HmacMD4的密钥:[B@2ebaa4a4
Bouncycastle HmacMD4算法摘要：[B@5f8f22f3
Bouncycastle HmacMD4Hex算法摘要：3f41ccbf594e0170f7073e8c756aa039 Bouncycastle HmacSHA224的密钥:[B@100a384
Bouncycastle HmacSHA224算法摘要：[B@50ef2f9f
Bouncycastle HmacSHA224算法摘要：f7d0e74f5c965f7981155206c05deccf0867e9cf348a1e9569b07353
执行结论是：
HMAC的特点。随意的消息大小。固定的输出长度。
HmacMD5算法摘要HEX：771093e83aeb659d125100fa465bd34e//32*4=128位
Bouncycastle HmacSHA1算法摘要HEX：c07963727b485cf6579d103a822382f3159bc6ee//40*4=160位
Bouncycastle HmacSHA256算法摘要HEX：2d211a42cb3fb68cd36255f9af4ef614eea6c8b93634183d333bf3e6e0b79d87//64*4=256
还有个问题就是。我们在使用HMAC的时候使用了hash函数而且增加了密钥key。那么这个key是怎么增加进去的？
A=[msg || key]还是B=[key || msg]，前缀和后缀的做法。前缀不可缺。有前缀的攻击，參考《深入浅出password学——经常使用加密技术原理与应用》马小婷的。后缀也有一种构建冲突攻击參考《深入浅出password学——经常使用加密技术原理与应用》马小婷。
HMAC方案是由一个内部哈希和一个外部哈希组成。他是Mihir Bellare、Ran Canetti和Hugo Krawczyk于1996年提出的。最大的一个有点就是存在安全证明。
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