java非对称加密笔记

package com.cc.utils.Security;

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;

public 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>
     * 用公钥解密
     * 
     * @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;
    }
}





package com.cc.utils.Security;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

import java.util.Map;

import org.junit.Before;
import org.junit.Test;

public class RSACoderTest {
    private String publicKey;
    private String privateKey;

    @Before
    public void setUp() throws Exception {
        Map<String, Object> keyMap = RSACoder.initKey();

        publicKey = RSACoder.getPublicKey(keyMap);
        privateKey = RSACoder.getPrivateKey(keyMap);
        System.err.println("公钥: \n\r" + publicKey);
        System.err.println("私钥： \n\r" + privateKey);
    }

    @Test
    public void test() throws Exception {
        System.err.println("公钥加密——私钥解密");
        String inputStr = "abc";
        byte[] data = inputStr.getBytes();

        byte[] encodedData = RSACoder.encryptByPublicKey(data, publicKey);

        byte[] decodedData = RSACoder.decryptByPrivateKey(encodedData, privateKey);

        String outputStr = new String(decodedData);
        System.err.println("加密前: " + inputStr + "\n\r" + "解密后: " + outputStr);
        assertEquals(inputStr, outputStr);

    }

    @Test
    public void testSign() throws Exception {
        System.err.println("私钥加密——公钥解密");
        String inputStr = "sign";
        byte[] data = inputStr.getBytes();

        byte[] encodedData = RSACoder.encryptByPrivateKey(data, privateKey);

        byte[] decodedData = RSACoder.decryptByPublicKey(encodedData, publicKey);

        String outputStr = new String(decodedData);
        System.err.println("加密前: " + inputStr + "\n\r" + "解密后: " + outputStr);
        assertEquals(inputStr, outputStr);

        System.err.println("私钥签名——公钥验证签名");
        // 产生签名
        String sign = RSACoder.sign(encodedData, privateKey);
        System.err.println("签名:\r" + sign);

        // 验证签名
        boolean status = RSACoder.verify(encodedData, publicKey, sign);
        System.err.println("状态:\r" + status);
        assertTrue(status);

    }

}



package com.cc.utils.Security;

import java.security.MessageDigest;

import javax.crypto.KeyGenerator;
import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

import org.junit.Test;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;


public 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);

    }
    
    
}
java非对称加密笔记

java非对称加密笔记

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