Coder.java
package com.sign.utils.rsa;
import java.security.MessageDigest;
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";
/**
* 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();
}
}
Rsa.java
package com.sign.utils.rsa;
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;
import org.junit.Test;
public class Rsa extends Coder {
public static final String KEY_ALGORTHM="RSA";//秘钥算法
public static final String SIGNATURE_ALGORITHM="MD5withRSA";//签名算法
public static final String PUBLIC_KEY = "RSAPublicKey";//公钥
public static final String PRIVATE_KEY = "RSAPrivateKey";//私钥
/*
* 初始化密钥
* @return
* @throws Exception
* RSA加密解密的实现，需要有一对公私密钥，公私密钥的初始化如下：
*/
public static Map<String,Object> initKey()throws Exception{
KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(KEY_ALGORTHM);
keyPairGenerator.initialize(1024);
KeyPair keyPair = keyPairGenerator.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;
}
/**
* 取得公钥，并转化为String类型
* @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());
}
/**
* 取得私钥，并转化为String类型
* @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());
}
//两种加密形式
//方法一
/*
* 用私钥加密
* @param data 加密数据
* @param key 密钥
* @return
* @throws Exception
*/
public static byte[] encryptByPrivateKey(byte[] data,String key)throws Exception{
//解密密钥
byte[] keyBytes = decryptBASE64(key);
//取私钥
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);
Key privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
//对数据加密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.ENCRYPT_MODE, privateKey);
return cipher.doFinal(data);
}
/**
* 私钥解密
* @param data 加密数据
* @param key 密钥
* @return
* @throws Exception
*/
public static byte[] decryptByPrivateKey(byte[] data,String key)throws Exception{
//对私钥解密
byte[] keyBytes = decryptBASE64(key);
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);
Key privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
//对数据解密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.DECRYPT_MODE, privateKey);
return cipher.doFinal(data);
}
//方式二
/**
* 用公钥加密
* @param data 加密数据
* @param key 密钥
* @return
* @throws Exception
*/
public static byte[] encryptByPublicKey(byte[] data,String key)throws Exception{
//对公钥解密
byte[] keyBytes = decryptBASE64(key);
//取公钥
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);
Key publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
//对数据解密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
return cipher.doFinal(data);
}
/**
* 私钥加密
* 用公钥解密
* @param data 加密数据
* @param key 密钥
* @return
* @throws Exception
*/
public static byte[] decryptByPublicKey(byte[] data,String key)throws Exception{
//对私钥解密
byte[] keyBytes = decryptBASE64(key);
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);
Key publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
//对数据解密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.DECRYPT_MODE, publicKey);
return cipher.doFinal(data);
}
/**
* 私钥签名
* 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{
//解密私钥
byte[] keyBytes = decryptBASE64(privateKey);
//构造PKCS8EncodedKeySpec对象
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(keyBytes);
//指定加密算法
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);
//取私钥匙对象
PrivateKey privateKey2 = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
//用私钥对信息生成数字签名
Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
signature.initSign(privateKey2);
signature.update(data);
return encryptBASE64(signature.sign());
}
/**
* 公钥校验
* 校验数字签名
* @param data 加密数据
* @param publicKey 公钥
* @param sign 数字签名
* @return
* @throws Exception
*/
public static boolean verify(byte[] data,String publicKey,String sign)throws Exception{
//解密公钥
byte[] keyBytes = decryptBASE64(publicKey);
//构造X509EncodedKeySpec对象
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(keyBytes);
//指定加密算法
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);
//取公钥匙对象
PublicKey publicKey2 = keyFactory.generatePublic(x509EncodedKeySpec);
Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
signature.initVerify(publicKey2);
signature.update(data);
//验证签名是否正常
return signature.verify(decryptBASE64(sign));
}
@Test
public void testRsa(){
try {
//test();
testSign();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void test() throws Exception {
Map<String, Object> keyMap = initKey();
String publicKey =getPublicKey(keyMap);
String privateKey = getPrivateKey(keyMap);
System.err.println("公钥加密——私钥解密");
String source = "这是一行没有任何意义的文字，你看完了等于没看，不是吗？";
System.out.println("\r加密前文字：\r\n" + source);
byte[] data = source.getBytes();
byte[] encodedData = encryptByPublicKey(data, publicKey);
System.out.println("加密后文字：\r\n" + new String(encodedData));
byte[] decodedData =decryptByPrivateKey(encodedData, privateKey);
String target = new String(decodedData);
System.out.println("解密后文字: \r\n" + target);
}
public void testSign() throws Exception {
Map<String, Object> keyMap = initKey();
String publicKey =getPublicKey(keyMap);
System.out.println(publicKey+"===================================");
String privateKey = getPrivateKey(keyMap);
System.err.println("私钥加密——公钥解密");
String source = "这是一行测试RSA数字签名的无意义文字";
System.out.println("原文字：\r\n" + source);
byte[] data = source.getBytes();
byte[] encodedData = encryptByPrivateKey(data, privateKey);
System.out.println("加密后：\r\n" + new String(encodedData));
byte[] decodedData = decryptByPublicKey(encodedData, publicKey);
String target = new String(decodedData);
System.out.println("解密后: \r\n" + target);
System.err.println("私钥签名——公钥验证签名");
String sign = sign(encodedData, privateKey);
System.err.println("签名:\r" + sign);
boolean status = verify(encodedData, publicKey, sign);
System.err.println("验证结果:\r" + status);
}
}
上面生成秘钥对的时候每次都生成的不一样，一般后台和app或其他设备交互只需要两对，写在配置文件中。