package com.tebon.ams.util;
import org.apache.commons.codec.binary.Base64;
import org.apache.log4j.Logger;
import javax.crypto.Cipher;
import java.security.*;
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;
/**
* @description: ${description}
* @author: dfz
* @create: 2019-05-16
**/
public class RSA {
private static Logger logger = Logger.getLogger(RSA.class);
private static final String KEY_ALGORITHM = "RSA";
private static final int RSA_KEY_SIZE = 1024;
public final static String UTF8 = "utf-8";
private static Map<Integer, String> keyMap = new HashMap<Integer, String>();
public static String formatString(String source) {
if (source == null) {
return null;
}
return source.replaceAll("\\r", "").replaceAll("\\n", "");
}
//用于封装随机产生的公钥与私钥
public static void main(String[] args) throws Exception {
//生成公钥和私钥
genKeyPair();
//加密字符串
String message = "df723820";
System.out.println("随机生成的公钥为:" + keyMap.get(0));
System.out.println("随机生成的私钥为:" + keyMap.get(1));
//公钥加密、私钥解密
String messageEn = encrypt(message, keyMap.get(0));
System.out.println(message + "公钥加密后的字符串为:" + messageEn);
String messageDe = decrypt(messageEn, keyMap.get(1));
System.out.println("私钥解密字符串为:" + messageDe);
//私钥加密、公钥解密
String enc = encryptByPrivateKey(message, keyMap.get(1));
System.out.println(message + "私钥加密后的字符串为:" + enc);
String de = decryptByPublicKey(enc, keyMap.get(0));
System.out.println("公钥解密后的字符串:" + de);
}
/**
* 随机生成密钥对
*
* @throws NoSuchAlgorithmException
*/
public static void genKeyPair() throws NoSuchAlgorithmException {
//KeyPairGenerator类用于生成公钥和私钥对,基于RSA算法生成对象
KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM);
//初始化密钥对生成器,密钥大小为96-1024位
keyPairGen.initialize(RSA_KEY_SIZE, new SecureRandom());
// 生成一个密钥对,保存在keyPair中
KeyPair keyPair = keyPairGen.generateKeyPair();
RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
// 得到私钥
RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
// 得到公钥
String publicKeyString = new String(Base64.encodeBase64(publicKey.getEncoded()));
// 得到私钥字符串
String privateKeyString = new String(Base64.encodeBase64((privateKey.getEncoded())));
// 将公钥和私钥保存到Map
keyMap.put(0, publicKeyString);// 0表示公钥
keyMap.put(1, privateKeyString);// 1表示私钥
}
/**
* RSA公钥加密
*
* @param str 加密字符串
* @param publicKey 公钥
* @return 密文
* @throws Exception 加密过程中的异常信息
*/
public static String encrypt(String str, String publicKey) throws Exception {
publicKey = formatString(publicKey);
//base64编码的公钥
byte[] decoded = Base64.decodeBase64(publicKey)