国密sm2，sm4（前台vue，后台java）加解密

项目背景

js端加密（使用sm-crypto）

1. 引入依赖：

    const sm4 = require('sm-crypto').sm4
    const sm2 = require('sm-crypto').sm2

2. sm2加密：

            const cipherMode = 0 // 1 - C1C3C2，0 - C1C2C3，默认为1
            sm2Encrypt(data) {
                // sm2加密密钥
                return '04' + sm2.doEncrypt(data, this.pubkeyHex, cipherMode);
            }

3. sm4加密：

            sm4Encrypt(data, key) {
                // sm4加密数据
                return sm4.encrypt(data, key);
            }

java端解密（使用Hutool工具包，需引入Bouncy Castle库的依赖）

1. 引入依赖包

    <dependency>
            <groupId>org.bouncycastle</groupId>
            <artifactId>bcprov-jdk15on</artifactId>
            <version>1.66</version>
        </dependency>
        <dependency>
            <groupId>org.bouncycastle</groupId>
            <artifactId>bcpkix-jdk15on</artifactId>
            <version>1.66</version>
        </dependency>
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.5.8</version>
        </dependency>

2. sm2生成密钥

    public static void generateKey() throws NoSuchAlgorithmException {
        // 1. bc库原始写法
        X9ECParameters x9ECParameters = GMNamedCurves.getByName("sm2p256v1");
        ECDomainParameters ecDomainParameters = new ECDomainParameters(x9ECParameters.getCurve(), x9ECParameters.getG(), x9ECParameters.getN());
        ECKeyPairGenerator ecKeyPairGenerator = new ECKeyPairGenerator();
        ecKeyPairGenerator.init(new ECKeyGenerationParameters(ecDomainParameters, SecureRandom.getInstance("SHA1PRNG")));
        AsymmetricCipherKeyPair asymmetricCipherKeyPair = ecKeyPairGenerator.generateKeyPair();

        //16进制格式的私钥，后端使用
        BigInteger privatekey = ((ECPrivateKeyParameters) asymmetricCipherKeyPair.getPrivate()).getD();
        String privateKeyHex = privatekey.toString(16);

        //16进制格式的公钥，发给前端
        ECPoint ecPoint = ((ECPublicKeyParameters) asymmetricCipherKeyPair.getPublic()).getQ();
        byte[] encoded = ecPoint.getEncoded(false);
        String publicKeyHex = Hex.toHexString(encoded);

        System.out.println(privateKeyHex);
        System.out.println(publicKeyHex);

        // 2. hutool写法
        SM2 sm2 = SmUtil.sm2();
        String hutoolPrivateKeyHex = HexUtil.encodeHexStr(BCUtil.encodeECPrivateKey(sm2.getPrivateKey()));
        String hutoolPublicKeyHex = HexUtil.encodeHexStr(((BCECPublicKey) sm2.getPublicKey()).getQ().getEncoded(false));
        System.out.println(hutoolPrivateKeyHex);
        System.out.println(hutoolPublicKeyHex);
    }

3. sm4生成密钥

        SM4 sm4 = new SM4();
        SecretKey secretKey = sm4.getSecretKey();
        byte[] encoded = secretKey.getEncoded();
        String encodeHexStr = HexUtil.encodeHexStr(encoded);

4. sm2解密

        // JS加密产生的密文
        String cipherData = "0477109887984ca6250635e6e30a58d11efe71abd998271808ec611366197698106b128ef699fe7fa09449bb7ca9527d674cc865a93a4e3593770ecd3ab06291aee81f5459b8500c284e5391956a83ddb2a90f298968a97828b0802749d5e5bbaa1c519489d4a37215ae0d5f7ef0b3a9a2e8dc1ce485544397a66923811c2f44a0";
        byte[] cipherDataByte = Hex.decode(cipherData);
        // 私钥
        String privateKey = "9fb1f241314168f56d0bc0a236c3a8d6f60ebf778e4104ce94a6cc27cdd4d178";
        // 1. 使用bc库解密
        X9ECParameters x9ECParameters = GMNamedCurves.getByName("sm2p256v1");
        ECDomainParameters ecDomainParameters = new ECDomainParameters(x9ECParameters.getCurve(), x9ECParameters.getG(), x9ECParameters.getN());
        ECPrivateKeyParameters privateKeyParameters = new ECPrivateKeyParameters(new BigInteger(privateKey, 16), ecDomainParameters);
        SM2Engine sm2Engine = new SM2Engine();
        sm2Engine.init(false, privateKeyParameters);
        byte[] bytes = sm2Engine.processBlock(cipherDataByte, 0, cipherDataByte.length);
        String data = new String(bytes, CharsetUtil.CHARSET_UTF_8);
        System.out.println(data);

        // 2. 使用hutool解密
        SM2 sm2 = new SM2(ECKeyUtil.toSm2PrivateParams(privateKey), null);
        sm2.setMode(SM2Engine.Mode.C1C2C3);
        sm2.setEncoding(new PlainDSAEncoding());

        String decryptStr = sm2.decryptStr(cipherData, KeyType.PrivateKey);
        System.out.println(decryptStr);

5. sm4解密

        SM4 sm4 = new SM4(HexUtil.decodeHex(key));
        String decryptStr = sm4.decryptStr(data);