国密算法 官方 java demo

国密算法 官方 java demo 实现指南

1. 整体流程

为了实现国密算法的官方 Java demo，我们需要按照以下步骤进行操作：

步骤 描述 1 下载并安装 JDK 2 导入相关依赖 3 创建国密算法相关的类 4 编写国密算法的代码 5 运行并验证国密算法的结果

2. 具体步骤和代码实现

2.1 下载并安装 JDK

首先，你需要从 Oracle 官网下载并安装最新版本的 JDK（Java Development Kit）。安装完成后，在命令行中输入 java -version 命令，确保 JDK 安装成功。

2.2 导入相关依赖

在 Java 项目中使用国密算法，需要导入相应的依赖。可以使用 Maven 进行依赖管理。在 pom.xml 文件中添加以下依赖：

<dependency>
    <groupId>org.bouncycastle</groupId>
    <artifactId>bcprov-jdk15on</artifactId>
    <version>1.68</version>
</dependency>

这个依赖是 Bouncy Castle 提供的 Java 密码学库，其中包含了国密算法的实现。

2.3 创建国密算法相关的类

在 Java 项目中，我们需要创建以下类来实现国密算法的相关操作：

2.3.1 SM2Cipher

import org.bouncycastle.crypto.InvalidCipherTextException;
import org.bouncycastle.crypto.engines.SM2Engine;
import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.crypto.signers.SM2Signer;

public class SM2Cipher {
    private ECPublicKeyParameters publicKey;
    private ECPrivateKeyParameters privateKey;

    public SM2Cipher(ECPublicKeyParameters publicKey, ECPrivateKeyParameters privateKey) {
        this.publicKey = publicKey;
        this.privateKey = privateKey;
    }

    public byte[] encrypt(byte[] data) throws InvalidCipherTextException {
        SM2Engine engine = new SM2Engine();
        engine.init(true, publicKey);
        return engine.processBlock(data, 0, data.length);
    }

    public byte[] decrypt(byte[] data) throws InvalidCipherTextException {
        SM2Engine engine = new SM2Engine();
        engine.init(false, privateKey);
        return engine.processBlock(data, 0, data.length);
    }

    public byte[] sign(byte[] data) {
        SM2Signer signer = new SM2Signer();
        signer.init(true, privateKey);
        signer.update(data, 0, data.length);
        return signer.generateSignature();
    }

    public boolean verify(byte[] data, byte[] signature) {
        SM2Signer signer = new SM2Signer();
        signer.init(false, publicKey);
        signer.update(data, 0, data.length);
        return signer.verifySignature(signature);
    }
}

这个类封装了 SM2 算法的加解密和签名验签功能。

2.3.2 SM2Utils

import org.bouncycastle.crypto.InvalidCipherTextException;
import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.crypto.util.PrivateKeyFactory;
import org.bouncycastle.crypto.util.PublicKeyFactory;
import org.bouncycastle.jce.provider.BouncyCastleProvider;

import java.security.Security;

public class SM2Utils {
    private static final String PROVIDER_NAME = "BC";
    private static final String KEY_ALGORITHM = "SM2";
    private static final String SIGNATURE_ALGORITHM = "SM3withSM2";

    static {
        Security.addProvider(new BouncyCastleProvider());
    }

    public static byte[] encrypt(byte[] publicKeyBytes, byte[] data) throws InvalidCipherTextException {
        ECPublicKeyParameters publicKey = (ECPublicKeyParameters) PublicKeyFactory.createKey(publicKeyBytes);
        SM2Cipher cipher = new SM2Cipher(publicKey, null);
        return cipher.encrypt(data);
    }

    public static byte[] decrypt(byte[] privateKeyBytes, byte[] encryptedData) throws InvalidCipherTextException {
        ECPrivateKeyParameters privateKey = (ECPrivateKeyParameters) PrivateKeyFactory.createKey(privateKeyBytes);
        SM2Cipher cipher = new SM2Cipher(null, privateKey);
        return cipher.decrypt(encryptedData);
    }

    public static byte[] sign(byte[] privateKeyBytes, byte[] data) {
        ECPrivateKeyParameters privateKey = (ECPrivateKeyParameters) PrivateKeyFactory.createKey(privateKeyBytes);
        SM2Cipher cipher = new SM2Cipher(null, privateKey);
        return cipher.sign(data);
    }

    public static boolean