Java中的各种加密算法

来源 http://blog.csdn.net/luckyzhoustar/article/details/50455407
Java中为我们提供了丰富的加密技术，可以基本的分为单向加密和非对称加密

1.单向加密算法

单向加密算法主要用来验证数据传输的过程中，是否被篡改过。

BASE64 严格地说，属于编码格式，而非加密算法

MD5(Message Digest algorithm 5，信息摘要算法)

SHA(Secure Hash Algorithm，安全散列算法)

HMAC(Hash Message Authentication Code，散列消息鉴别码

2.对称和非对称加密算法
对称和非对称加密算法主要采用公钥和私钥的形式，来对数据加密。

DES(Data Encryption Standard，数据加密算法)

PBE(Password-based encryption，基于密码验证)

RSA(算法的名字以发明者的名字命名：Ron Rivest, AdiShamir 和Leonard Adleman)

DH(Diffie-Hellman算法，密钥一致协议)

DSA(Digital Signature Algorithm，数字签名)

ECC(Elliptic Curves Cryptography，椭圆曲线密码编码学)

更多理论的简介，请自行查阅，下面提供代码，来看一下。

基础加密

[java] view
plain copy

print?

<span style="font-family:Comic Sans MS;font-size:18px;">package com.test;

import java.security.MessageDigest;

import javax.crypto.KeyGenerator;

import javax.crypto.Mac;

import javax.crypto.SecretKey;

import javax.crypto.spec.SecretKeySpec;

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

/**

* @ClassName: coder

* @Description: 加密组件

* @author: LUCKY

* @date:2016年1月4日 下午1:24:12

*/

public abstract class coder {

public static final String KEY_SHA = "SHA";

public static final String KEY_MD5 = "MD5";

/**

* MAC算法可选以下多种算法

*

* <pre>

* HmacMD5

* HmacSHA1

* HmacSHA256

* HmacSHA384

* HmacSHA512

* </pre>

*/

public static final String KEY_MAC = "HmacMD5";

/**

* BASE64解密

*

* @param key

* @return

* @throws Exception

*/

public static byte[] decryptBASE64(String key) throws Exception {

return (new BASE64Decoder()).decodeBuffer(key);

}

/**

* BASE64加密

*

* @param key

* @return

* @throws Exception

*/

public static String encryptBASE64(byte[] key) throws Exception {

return (new BASE64Encoder()).encodeBuffer(key);

}

/**

* MD5加密

*

* @param data

* @return

* @throws Exception

*/

public static byte[] encryptMD5(byte[] data) throws Exception {

MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);

md5.update(data);

return md5.digest();

}

/**

* SHA加密

*

* @param data

* @return

* @throws Exception

*/

public static byte[] encryptSHA(byte[] data) throws Exception {

MessageDigest sha = MessageDigest.getInstance(KEY_SHA);

sha.update(data);

return sha.digest();

}

/**

* 初始化HMAC密钥

*

* @return

* @throws Exception

*/

public static String initMacKey() throws Exception {

KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_MAC);

SecretKey secretKey = keyGenerator.generateKey();

return encryptBASE64(secretKey.getEncoded());

}

/**

* HMAC加密

*

* @param data

* @param key

* @return

* @throws Exception

*/

public static byte[] encryptHMAC(byte[] data, String key) throws Exception {

SecretKey secretKey = new SecretKeySpec(decryptBASE64(key), KEY_MAC);

Mac mac = Mac.getInstance(secretKey.getAlgorithm());

mac.init(secretKey);

return mac.doFinal(data);

}

}</span>

RSA安全编码组件

[java] view
plain copy

print?

<span style="font-family:Comic Sans MS;font-size:18px;">package com.test;

import java.security.Key;

import java.security.KeyFactory;

import java.security.KeyPair;

import java.security.KeyPairGenerator;

import java.security.PrivateKey;

import java.security.PublicKey;

import java.security.Signature;

import java.security.interfaces.RSAPrivateKey;

import java.security.interfaces.RSAPublicKey;

import java.security.spec.PKCS8EncodedKeySpec;

import java.security.spec.X509EncodedKeySpec;

import java.util.HashMap;

import java.util.Map;

import javax.crypto.Cipher;

/**

* @ClassName: RSACoder

* @Description: RSA安全编码组件

* @author: LUCKY

* @date:2016年1月4日 下午1:25:34

*/

public abstract class RSACoder extends coder {

public static final String KEY_ALGORITHM = "RSA";

public static final String SIGNATURE_ALGORITHM = "MD5withRSA";

private static final String PUBLIC_KEY = "RSAPublicKey";

private static final String PRIVATE_KEY = "RSAPrivateKey";

/**

* 用私钥对信息生成数字签名

*

* @param data

* 加密数据

* @param privateKey

* 私钥

*

* @return

* @throws Exception

*/

public static String sign(byte[] data, String privateKey) throws Exception {

// 解密由base64编码的私钥

byte[] keyBytes = decryptBASE64(privateKey);

// 构造PKCS8EncodedKeySpec对象

PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);

// KEY_ALGORITHM 指定的加密算法

KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);

// 取私钥匙对象

PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);

// 用私钥对信息生成数字签名

Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);

signature.initSign(priKey);

signature.update(data);

return encryptBASE64(signature.sign());

}

/**

* 校验数字签名

*

* @param data

* 加密数据

* @param publicKey

* 公钥

* @param sign

* 数字签名

*

* @return 校验成功返回true 失败返回false

* @throws Exception

*

*/

public static boolean verify(byte[] data, String publicKey, String sign)

throws Exception {

// 解密由base64编码的公钥

byte[] keyBytes = decryptBASE64(publicKey);

// 构造X509EncodedKeySpec对象

X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);

// KEY_ALGORITHM 指定的加密算法

KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);

// 取公钥匙对象

PublicKey pubKey = keyFactory.generatePublic(keySpec);

Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);

signature.initVerify(pubKey);

signature.update(data);

// 验证签名是否正常

return signature.verify(decryptBASE64(sign));

}

/**

* 解密<br>

* 用私钥解密

*

* @param data

* @param key

* @return

* @throws Exception

*/

public static byte[] decryptByPrivateKey(byte[] data, String key)

throws Exception {

// 对密钥解密

byte[] keyBytes = decryptBASE64(key);

// 取得私钥

PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);

KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);

Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);

// 对数据解密

Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());

cipher.init(Cipher.DECRYPT_MODE, privateKey);

return cipher.doFinal(data);

}

/**

* 解密<br>

* 用私钥解密

*

* @param data

* @param key

* @return

* @throws Exception

*/

public static byte[] decryptByPublicKey(byte[] data, String key)

throws Exception {

// 对密钥解密

byte[] keyBytes = decryptBASE64(key);

// 取得公钥

X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);

KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);

Key publicKey = keyFactory.generatePublic(x509KeySpec);

// 对数据解密

Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());

cipher.init(Cipher.DECRYPT_MODE, publicKey);

return cipher.doFinal(data);

}

/**

* 加密<br>

* 用公钥加密

*

* @param data

* @param key

* @return

* @throws Exception

*/

public static byte[] encryptByPublicKey(byte[] data, String key)

throws Exception {

// 对公钥解密

byte[] keyBytes = decryptBASE64(key);

// 取得公钥

X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);

KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);

Key publicKey = keyFactory.generatePublic(x509KeySpec);

// 对数据加密

Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());

cipher.init(Cipher.ENCRYPT_MODE, publicKey);

return cipher.doFinal(data);

}

/**

* 加密<br>

* 用私钥加密

*

* @param data

* @param key

* @return

* @throws Exception

*/

public static byte[] encryptByPrivateKey(byte[] data, String key)

throws Exception {

// 对密钥解密

byte[] keyBytes = decryptBASE64(key);

// 取得私钥

PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);

KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);

Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);

// 对数据加密

Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());

cipher.init(Cipher.ENCRYPT_MODE, privateKey);

return cipher.doFinal(data);

}

/**

* 取得私钥

*

* @param keyMap

* @return

* @throws Exception

*/

public static String getPrivateKey(Map<String, Object> keyMap)

throws Exception {

Key key = (Key) keyMap.get(PRIVATE_KEY);

return encryptBASE64(key.getEncoded());

}

/**

* 取得公钥

*

* @param keyMap

* @return

* @throws Exception

*/

public static String getPublicKey(Map<String, Object> keyMap)

throws Exception {

Key key = (Key) keyMap.get(PUBLIC_KEY);

return encryptBASE64(key.getEncoded());

}

/**

* 初始化密钥

*

* @return

* @throws Exception

*/

public static Map<String, Object> initKey() throws Exception {

KeyPairGenerator keyPairGen = KeyPairGenerator

.getInstance(KEY_ALGORITHM);

keyPairGen.initialize(1024);

KeyPair keyPair = keyPairGen.generateKeyPair();

// 公钥

RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();

// 私钥

RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();

Map<String, Object> keyMap = new HashMap<String, Object>(2);

keyMap.put(PUBLIC_KEY, publicKey);

keyMap.put(PRIVATE_KEY, privateKey);

return keyMap;

}

}</span>