国密SM2算法进行数据的加密、签名和验签、解密

本文主要是介绍国密SM2算法进行数据的加密、签名和验签、解密，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

一、背景介绍

数据的加解密有很多种方式，几种常用的加密算法如下：

DES（Data Encryption Standard）：对称算法，数据加密标准，速度较快，适用于加密大量数据的场合；

3DES（Triple DES）：是基于DES的对称算法，对一块数据用三个不同的密钥进行三次加密，强度更高；

RC2和RC4：对称算法，用变长密钥对大量数据进行加密，比 DES 快；

IDEA（International Data Encryption Algorithm）国际数据加密算法，使用 128 位密钥提供非常强的安全性；

RSA：由 RSA 公司发明，是一个支持变长密钥的公共密钥算法，需要加密的文件块的长度也是可变的，非对称算法

本文着重介绍SM2国密算法的使用，这是一款中国国家密码局发布的一款加密算法，本文介绍使用语言环境为java语言

二、引入pom依赖

<dependency><groupId>org.bouncycastle</groupId><artifactId>bcprov-jdk15on</artifactId><version>1.70</version>
</dependency>
<dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><scope>provided</scope>
</dependency>

主要是引入了工具包和lombok依赖

三、国密公私钥对工具类KeyUtils

package com.hl.sm2demo.util;import lombok.extern.slf4j.Slf4j;
import org.bouncycastle.jce.provider.BouncyCastleProvider;import java.security.*;
import java.security.spec.ECGenParameterSpec;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Base64;
import java.util.Map;/*** @ Description 国密公私钥对工具类*/
@Slf4j
public class KeyUtils {public static final String PUBLIC_KEY = "publicKey";public static final String PRIVATE_KEY = "privateKey";/*** 生成国密公私钥对*/public static Map<String, String> generateSmKey() throws Exception {KeyPairGenerator keyPairGenerator = null;SecureRandom secureRandom = new SecureRandom();ECGenParameterSpec sm2Spec = new ECGenParameterSpec("sm2p256v1");keyPairGenerator = KeyPairGenerator.getInstance("EC", new BouncyCastleProvider());keyPairGenerator.initialize(sm2Spec);keyPairGenerator.initialize(sm2Spec, secureRandom);KeyPair keyPair = keyPairGenerator.generateKeyPair();PrivateKey privateKey = keyPair.getPrivate();PublicKey publicKey = keyPair.getPublic();String publicKeyStr = new String(Base64.getEncoder().encode(publicKey.getEncoded()));String privateKeyStr = new String(Base64.getEncoder().encode(privateKey.getEncoded()));return Map.of(PUBLIC_KEY, publicKeyStr, PRIVATE_KEY, privateKeyStr);}/*** 将Base64转码的公钥串，转化为公钥对象*/public static PublicKey createPublicKey(String publicKey) {PublicKey publickey = null;try {X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(Base64.getDecoder().decode(publicKey));KeyFactory keyFactory = KeyFactory.getInstance("EC", new BouncyCastleProvider());publickey = keyFactory.generatePublic(publicKeySpec);} catch (Exception e) {log.error("将Base64转码的公钥串，转化为公钥对象异常：{}", e.getMessage(), e);}return publickey;}/*** 将Base64转码的私钥串，转化为私钥对象*/public static PrivateKey createPrivateKey(String privateKey) {PrivateKey publickey = null;try {PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.getDecoder().decode(privateKey));KeyFactory keyFactory = KeyFactory.getInstance("EC", new BouncyCastleProvider());publickey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);} catch (Exception e) {log.error("将Base64转码的私钥串，转化为私钥对象异常：{}", e.getMessage(), e);}return publickey;}}

生成公私钥字符串map对象，公钥串转公钥对象方法和私钥串转私钥对象方法

四、 SM2工具类

package com.hl.sm2demo.util;import lombok.extern.slf4j.Slf4j;
import org.bouncycastle.asn1.gm.GMObjectIdentifiers;
import org.bouncycastle.crypto.InvalidCipherTextException;
import org.bouncycastle.crypto.engines.SM2Engine;
import org.bouncycastle.crypto.params.ECDomainParameters;
import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.crypto.params.ParametersWithRandom;
import org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPrivateKey;
import org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPublicKey;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.jce.spec.ECParameterSpec;import java.security.*;/*** @ Description SM2实现工具类*/
@Slf4j
public class Sm2Util {

/*    这行代码是在Java中用于向安全系统添加Bouncy Castle安全提供器的。Bouncy Castle是一个流行的开源加密库，它提供了许多密码学算法和安全协议的实现。通过调用Security.addProvider并传入BouncyCastleProvider对象，你可以注册Bouncy Castle提供的安全服务和算法到Java的安全框架中。这样一来，你就可以在你的应用程序中使用Bouncy Castle所提供的加密算法、密钥生成和管理等功能。*/static {Security.addProvider(new BouncyCastleProvider());}/*** 根据publicKey对原始数据data，使用SM2加密*/public static byte[] encrypt(byte[] data, PublicKey publicKey) {ECPublicKeyParameters localECPublicKeyParameters = getEcPublicKeyParameters(publicKey);SM2Engine localSM2Engine = new SM2Engine();localSM2Engine.init(true, new ParametersWithRandom(localECPublicKeyParameters, new SecureRandom()));byte[] arrayOfByte2;try {arrayOfByte2 = localSM2Engine.processBlock(data, 0, data.length);return arrayOfByte2;} catch (InvalidCipherTextException e) {log.error("SM2加密失败:{}", e.getMessage(), e);return null;}}private static ECPublicKeyParameters getEcPublicKeyParameters(PublicKey publicKey) {ECPublicKeyParameters localECPublicKeyParameters = null;if (publicKey instanceof BCECPublicKey localECPublicKey) {ECParameterSpec localECParameterSpec = localECPublicKey.getParameters();ECDomainParameters localECDomainParameters = new ECDomainParameters(localECParameterSpec.getCurve(),localECParameterSpec.getG(), localECParameterSpec.getN());localECPublicKeyParameters = new ECPublicKeyParameters(localECPublicKey.getQ(), localECDomainParameters);}return localECPublicKeyParameters;}/*** 根据privateKey对加密数据encode data，使用SM2解密*/public static byte[] decrypt(byte[] encodeData, PrivateKey privateKey) {SM2Engine localSM2Engine = new SM2Engine();BCECPrivateKey sm2PriK = (BCECPrivateKey) privateKey;ECParameterSpec localECParameterSpec = sm2PriK.getParameters();ECDomainParameters localECDomainParameters = new ECDomainParameters(localECParameterSpec.getCurve(),localECParameterSpec.getG(), localECParameterSpec.getN());ECPrivateKeyParameters localECPrivateKeyParameters = new ECPrivateKeyParameters(sm2PriK.getD(),localECDomainParameters);localSM2Engine.init(false, localECPrivateKeyParameters);try {return localSM2Engine.processBlock(encodeData, 0, encodeData.length);} catch (InvalidCipherTextException e) {log.error("SM2解密失败:{}", e.getMessage(), e);return null;}}/*** 私钥签名*/public static byte[] signByPrivateKey(byte[] data, PrivateKey privateKey) throws Exception {Signature sig = Signature.getInstance(GMObjectIdentifiers.sm2sign_with_sm3.toString(), BouncyCastleProvider.PROVIDER_NAME);sig.initSign(privateKey);sig.update(data);return sig.sign();}/*** 公钥验签*/public static boolean verifyByPublicKey(byte[] data, PublicKey publicKey, byte[] signature) throws Exception {Signature sig = Signature.getInstance(GMObjectIdentifiers.sm2sign_with_sm3.toString(), BouncyCastleProvider.PROVIDER_NAME);sig.initVerify(publicKey);sig.update(data);return sig.verify(signature);}}

五、案例测试Junit

package com.hl.sm2demo;import com.hl.sm2demo.util.KeyUtils;
import com.hl.sm2demo.util.Sm2Util;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;import java.security.PrivateKey;
import java.security.PublicKey;
import java.util.Base64;
import java.util.Map;@SpringBootTest
class Sm2DemoApplicationTests {PublicKey publicKey = null;PrivateKey privateKey = null;@Testpublic void test() throws Exception {//生成公私钥对Map<String,String> keys = KeyUtils.generateSmKey();String testStr = "hello JAVA";System.out.println("原始字符串：" + testStr);System.out.println("公钥：" + keys.get(KeyUtils.PUBLIC_KEY));publicKey = KeyUtils.createPublicKey(keys.get(KeyUtils.PUBLIC_KEY));System.out.println("私钥：" + keys.get(KeyUtils.PRIVATE_KEY));privateKey = KeyUtils.createPrivateKey(keys.get(KeyUtils.PRIVATE_KEY));System.out.println();//公钥加密byte[] encrypt = Sm2Util.encrypt(testStr.getBytes(), publicKey);//加密转base64String encryptBase64Str = Base64.getEncoder().encodeToString(encrypt);System.out.println("加密数据：" + encryptBase64Str);//私钥签名,方便对方收到数据后用公钥验签byte[] sign = Sm2Util.signByPrivateKey(testStr.getBytes(), privateKey);System.out.println("数据签名：" + Base64.getEncoder().encodeToString(sign));//公钥验签，验证通过后再进行数据解密boolean b = Sm2Util.verifyByPublicKey(testStr.getBytes(), publicKey, sign);System.out.println("数据验签：" + b);//私钥解密byte[] decode = Base64.getDecoder().decode(encryptBase64Str);byte[] decrypt = Sm2Util.decrypt(decode, privateKey);assert decrypt != null;System.out.println("解密数据：" + new String(decrypt));}
}

测试代码主要逻辑：

密钥准备：首先生成一个公私钥对字符串，再使用工具分别转换为公私钥的java对象；

加密过程：把数据使用公钥加密，把密文转换成base64编码格式，再用私钥签名；

解密过程：拿到加密数据后用公钥验签，以确保密文数据没有被第三方拦截篡改，验证通过后，base64解码，最后使用私钥进行解密，还原数据

测试结果如下图：