package com.geostar.gfstack.cas.util; import org.apache.commons.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; /**
* RSA加解密工具类，实现公钥加密私钥解密和私钥解密公钥解密
*/
public class RSAUtils { private static final String src = "abcdefghijklmnopqrstuvwxyz"; public static void main(String[] args) throws Exception {
System.out.println("\n");
RSAKeyPair keyPair = generateKeyPair();
System.out.println("公钥：" + keyPair.getPublicKey());
System.out.println("私钥：" + keyPair.getPrivateKey());
System.out.println("\n");
test1(keyPair, src);
System.out.println("\n");
test2(keyPair, src);
System.out.println("\n");
} /**
* 公钥加密私钥解密
*/
private static void test1(RSAKeyPair keyPair, String source) throws Exception {
System.out.println("***************** 公钥加密私钥解密开始 *****************");
String text1 = encryptByPublicKey(keyPair.getPublicKey(), source);
String text2 = decryptByPrivateKey(keyPair.getPrivateKey(), text1);
System.out.println("加密前：" + source);
System.out.println("加密后：" + text1);
System.out.println("解密后：" + text2);
if (source.equals(text2)) {
System.out.println("解密字符串和原始字符串一致，解密成功");
} else {
System.out.println("解密字符串和原始字符串不一致，解密失败");
}
System.out.println("***************** 公钥加密私钥解密结束 *****************");
} /**
* 私钥加密公钥解密
*
* @throws Exception
*/
private static void test2(RSAKeyPair keyPair, String source) throws Exception {
System.out.println("***************** 私钥加密公钥解密开始 *****************");
String text1 = encryptByPrivateKey(keyPair.getPrivateKey(), source);
String text2 = decryptByPublicKey(keyPair.getPublicKey(), text1);
System.out.println("加密前：" + source);
System.out.println("加密后：" + text1);
System.out.println("解密后：" + text2);
if (source.equals(text2)) {
System.out.println("解密字符串和原始字符串一致，解密成功");
} else {
System.out.println("解密字符串和原始字符串不一致，解密失败");
}
System.out.println("***************** 私钥加密公钥解密结束 *****************");
} /**
* 公钥解密
*
* @param publicKeyText
* @param text
* @return
* @throws Exception
*/
public static String decryptByPublicKey(String publicKeyText, String text) throws Exception {
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyText));
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.DECRYPT_MODE, publicKey);
byte[] result = cipher.doFinal(Base64.decodeBase64(text));
return new String(result);
} /**
* 私钥加密
*
* @param privateKeyText
* @param text
* @return
* @throws Exception
*/
public static String encryptByPrivateKey(String privateKeyText, String text) throws Exception {
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyText));
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, privateKey);
byte[] result = cipher.doFinal(text.getBytes());
return Base64.encodeBase64String(result);
} /**
* 私钥解密
*
* @param privateKeyText
* @param text
* @return
* @throws Exception
*/
public static String decryptByPrivateKey(String privateKeyText, String text) throws Exception {
PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyText));
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.DECRYPT_MODE, privateKey);
byte[] result = cipher.doFinal(Base64.decodeBase64(text));
return new String(result);
} /**
* 公钥加密
*
* @param publicKeyText
* @param text
* @return
*/
public static String encryptByPublicKey(String publicKeyText, String text) throws Exception {
X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyText));
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
byte[] result = cipher.doFinal(text.getBytes());
return Base64.encodeBase64String(result);
} /**
* 构建RSA密钥对
*
* @return
* @throws NoSuchAlgorithmException
*/
public static RSAKeyPair generateKeyPair() throws NoSuchAlgorithmException {
KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
keyPairGenerator.initialize(1024);
KeyPair keyPair = keyPairGenerator.generateKeyPair();
RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded());
String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
RSAKeyPair rsaKeyPair = new RSAKeyPair(publicKeyString, privateKeyString);
return rsaKeyPair;
} /**
* RSA密钥对对象
*/
public static class RSAKeyPair { private String publicKey;
private String privateKey; public RSAKeyPair(String publicKey, String privateKey) {
this.publicKey = publicKey;
this.privateKey = privateKey;
} public String getPublicKey() {
return publicKey;
} public String getPrivateKey() {
return privateKey;
} } }
参考：https://www.jianshu.com/p/048be4864559
