io.github.shitsurei.common.util.RSAUtil Maven / Gradle / Ivy
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package io.github.shitsurei.common.util;
import io.github.shitsurei.dao.enumerate.system.GlobalExceptionEnum;
import io.github.shitsurei.dao.exception.GlobalException;
import com.google.common.collect.ImmutableMap;
import org.apache.tomcat.util.codec.binary.Base64;
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.Map;
/**
* @author zgr
* @Description rsa非对称加密工具类
* @createTime 2022年02月26日 22:05:00
*/
public class RSAUtil {
/**
* 非对称密钥算法
*/
private static final String KEY_ALGORITHM = "RSA";
/**
* 密钥长度，DH算法的默认密钥长度是1024
* 密钥长度必须是64的倍数，在512到65536位之间
*/
private static final int KEY_SIZE = 512;
//公钥
private static final String PUBLIC_KEY = "RSAPublicKey";
//私钥
private static final String PRIVATE_KEY = "RSAPrivateKey";
/**
* 初始化密钥对
*
* @return Map 甲方密钥的Map
*/
public static Map initKey() {
//实例化密钥生成器
KeyPairGenerator keyPairGenerator = null;
try {
keyPairGenerator = KeyPairGenerator.getInstance(KEY_ALGORITHM);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
assert keyPairGenerator != null;
//初始化密钥生成器
keyPairGenerator.initialize(KEY_SIZE);
//生成密钥对
KeyPair keyPair = keyPairGenerator.generateKeyPair();
//甲方公钥
RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
//甲方私钥
RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
//将密钥存储在map中
return ImmutableMap.of(
PUBLIC_KEY, publicKey,
PRIVATE_KEY, privateKey
);
}
/**
* 私钥加密
*
* @param data 待加密数据
* @param key 密钥
* @return byte[] 加密数据
*/
private static byte[] encryptByPrivateKey(byte[] data, byte[] key) throws Exception {
//取得私钥
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(key);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
//生成私钥
PrivateKey privateKey = keyFactory.generatePrivate(pkcs8KeySpec);
//数据加密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.ENCRYPT_MODE, privateKey);
return cipher.doFinal(data);
}
/**
* 公钥加密
*
* @param data 待加密数据
* @param key 密钥
* @return byte[] 加密数据
*/
private static byte[] encryptByPublicKey(byte[] data, byte[] key) throws Exception {
//实例化密钥工厂
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
//初始化公钥
//密钥材料转换
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(key);
//产生公钥
PublicKey pubKey = keyFactory.generatePublic(x509KeySpec);
//数据加密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.ENCRYPT_MODE, pubKey);
return cipher.doFinal(data);
}
/**
* 私钥解密
*
* @param data 待解密数据
* @param key 密钥
* @return byte[] 解密数据
*/
private static byte[] decryptByPrivateKey(byte[] data, byte[] key) throws Exception {
//取得私钥
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(key);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
//生成私钥
PrivateKey privateKey = keyFactory.generatePrivate(pkcs8KeySpec);
//数据解密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.DECRYPT_MODE, privateKey);
return cipher.doFinal(data);
}
/**
* 公钥解密
*
* @param data 待解密数据
* @param key 密钥
* @return byte[] 解密数据
*/
public static byte[] decryptByPublicKey(byte[] data, byte[] key) throws Exception {
//实例化密钥工厂
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
//初始化公钥
//密钥材料转换
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(key);
//产生公钥
PublicKey pubKey = keyFactory.generatePublic(x509KeySpec);
//数据解密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.DECRYPT_MODE, pubKey);
return cipher.doFinal(data);
}
/**
* 取得私钥
*
* @param keyMap 密钥map
* @return String 私钥
*/
public static String getPrivateKey(Map keyMap) {
Key key = (Key) keyMap.get(PRIVATE_KEY);
return Base64.encodeBase64String(key.getEncoded());
}
/**
* 取得公钥
*
* @param keyMap 密钥map
* @return String 公钥
*/
public static String getPublicKey(Map keyMap) {
Key key = (Key) keyMap.get(PUBLIC_KEY);
return Base64.encodeBase64String(key.getEncoded());
}
/**
* 私钥加密
*
* @param rawString
* @return
*/
public static String encrypt(String rawString, String privateKey) {
String cryptStr;
try {
cryptStr = Base64.encodeBase64String(encryptByPrivateKey(rawString.getBytes(), Base64.decodeBase64(privateKey)));
} catch (Exception exception) {
throw new GlobalException(GlobalExceptionEnum.CRYPT_ERROR);
}
return cryptStr;
}
/**
* 私钥解密
*
* @param cryptString
* @param privateKey
* @return
*/
public static String decrypt(String cryptString, String privateKey) {
String rawStr;
try {
rawStr = new String(decryptByPrivateKey(Base64.decodeBase64(cryptString), Base64.decodeBase64(privateKey)));
} catch (Exception exception) {
throw new GlobalException(GlobalExceptionEnum.CRYPT_ERROR);
}
return rawStr;
}
/**
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
//初始化密钥对
Map keyMap = RSAUtil.initKey();
//公钥
String publicKey = RSAUtil.getPublicKey(keyMap);
//私钥
String privateKey = RSAUtil.getPrivateKey(keyMap);
System.out.println("公钥：/n" + publicKey);
System.out.println("私钥：/n" + privateKey);
System.out.println("================密钥对构造完毕,甲方将公钥公布给乙方，开始进行加密数据的传输=============");
String str = "RSA密码交换算法";
System.out.println("===========甲方向乙方发送加密数据==============");
System.out.println("原文:" + str);
//甲方进行数据的加密
byte[] code1 = encryptByPrivateKey(str.getBytes(), Base64.decodeBase64(privateKey));
System.out.println("加密后的数据：" + Base64.encodeBase64String(code1));
System.out.println("===========乙方使用甲方提供的公钥对数据进行解密==============");
//乙方进行数据的解密
byte[] decode1 = decryptByPublicKey(code1, Base64.decodeBase64(publicKey));
System.out.println("乙方解密后的数据：" + new String(decode1) + "/n/n");
System.out.println("===========反向进行操作，乙方向甲方发送数据==============/n/n");
str = "乙方向甲方发送数据RSA算法";
System.out.println("原文:" + str);
//乙方使用公钥对数据进行加密
byte[] code2 = encryptByPublicKey(str.getBytes(), Base64.decodeBase64(publicKey));
System.out.println("===========乙方使用公钥对数据进行加密==============");
System.out.println("加密后的数据：" + Base64.encodeBase64String(code2));
System.out.println("=============乙方将数据传送给甲方======================");
System.out.println("===========甲方使用私钥对数据进行解密==============");
//甲方使用私钥对数据进行解密
byte[] decode2 = decryptByPrivateKey(code2, Base64.decodeBase64(privateKey));
System.out.println("甲方解密后的数据：" + new String(decode2));
}
}