使用国密2（SM2）前后端传输加密

@Data
@AllArgsConstructor
static class SM2KeyPair {
    // 公钥
    private String publicKey;

    // 前端公钥
    private String publicQKey;

    // 私钥
    private String privateKey;

}

// 生成密钥对
public static SM2KeyPair getSm2KeyPair() {
    SM2 sm2= SmUtil.sm2();
    // 公钥
    String publickey=sm2.getPublicKeybase64();
    // 前端公钥
    String publicQkey = HexUtil.encodeHexStr(((BCECPublicKey)sm2.getPublicKey()).getQ().getEncoded(false));
    // 私钥
    String privatekey=sm2.getPrivateKeybase64();
    return new SM2KeyPair(publickey,publicQkey,privatekey);
}

// 公钥加密
public static String encrypt(String data, String publickey) {
    SM2 sm2=SmUtil.sm2(null,publickey);
    String encryptStr = sm2.encryptBcd(data, KeyType.PublicKey);
    return encryptStr;
}

// 私钥解密 公钥加密密文
public static String decrypt(String encryptStr, String privatekey){
    if(!encryptStr.startsWith("04")){
        encryptStr="04".concat(encryptStr);
    }
    SM2 sm2=SmUtil.sm2(privatekey,null);
    String decryptStr = StrUtil.utf8Str(sm2.decryptFromBcd(encryptStr, KeyType.PrivateKey));
    return decryptStr;
}

// 私钥签名
public static String signByPrivateKey(String data, String privatekey){
    SM2 sm2= SmUtil.sm2(privatekey,null);
    String sign = sm2.signHex(HexUtil.encodeHexStr(data));
    return sign;
}

// 公钥验签
public static boolean verifyByPublicKey(String data, String publickey, String signature){
    SM2 sm2= SmUtil.sm2(null,publickey);
    boolean verify = sm2.verifyHex(HexUtil.encodeHexStr(data), signature);
    return verify;
}

// 创建私钥、公钥
SM2KeyPair sm2KeyPair = getSm2KeyPair();
// 后端公钥
String publickey = sm2KeyPair.getPublicKey();
// 前端公钥
String publicQkey = sm2KeyPair.getPublicQKey()
// 后端私钥
String privateKey = sm2KeyPair.getPrivateKey();

System.out.println("公钥：" + publickey);
System.out.println("私钥：" + privateKey);
System.out.println("------------------");
System.out.println("公钥（前端）：" + publicQkey);

公钥：MFkwEwYHKoZIzj0CAQYIKoEcz1UBgi0DQgAEq+OqrQd71xbWD50ks7zfikU7ec64O8fp0d6yuEbadmURoZl4P07I1aEm4bjGvxmP6XP65tqNJWgTDomLhvrpUQ==
私钥：MIGTAgEAMBMGByqGSM49AgEGCCqBHM9VAYItBHkwdwIBAQQgn1ABWedtUoujWXCCwMfKnCXLgj1riMWf/S2SB6xodZKgCgYIKoEcz1UBgi2hRANCAASr46qtB3vXFtYPnSSzvN+KRTt5zrg7x+nR3rK4Rtp2ZRGhmXg/TsjVoSbhuMa/GY/pc/rm2o0laBMOiYuG+ulR
------------------
公钥（前端）：04abe3aaad077bd716d60f9d24b3bcdf8a453b79ceb83bc7e9d1deb2b846da766511a199783f4ec8d5a126e1b8c6bf198fe973fae6da8d2568130e898b86fae951

const sm2 = require('sm-crypto').sm2
// 明文
const msgString = '123456abcd你好'
// 公钥（base64）
const publicKey = '04abe3aaad077bd716d60f9d24b3bcdf8a453b79ceb83bc7e9d1deb2b846da766511a199783f4ec8d5a126e1b8c6bf198fe973fae6da8d2568130e898b86fae951'
// 加密
let encryptData = sm2.doEncrypt(msgString, publicKey) // 加密结果
console.log('密文：')
console.log(encryptData)

// 密文由后端通过私钥解密

密文：
0ed81be5ba87e0eccdf04ff75e2ce2b75cb9679a237622e2af115311f426437298e39d5a1619429952cc824a4199c50db6b86524a4fbeb224f9be5012ac6c0bc1f6750eb742459b4577ca3a3873463254aea629032d6e7ce4419b981c9fc24eee73ce33fc7ca42064c464fbb399660c1

// 后端密钥
String privateKey = "MIGTAgEAMBMGByqGSM49AgEGCCqBHM9VAYItBHkwdwIBAQQgn1ABWedtUoujWXCCwMfKnCXLgj1riMWf/S2SB6xodZKgCgYIKoEcz1UBgi2hRANCAASr46qtB3vXFtYPnSSzvN+KRTt5zrg7x+nR3rK4Rtp2ZRGhmXg/TsjVoSbhuMa/GY/pc/rm2o0laBMOiYuG+ulR";

// 密文
String encryptStr = "0e6f7da2aabd4ead9d0aee5e85ba72bdd20f49f28e0f6653674fe235250eec9227c4dec6211289623f77563092fa7c2f36a6fb675eefee7fcb1185cf14c31bb1153875168487f23a400d0e9d25f71d37228cf1c42b76a1a6816771b5169af56c7194fd3c9d3ed7dc5f8bfa063de7b849";

// 解密
String decrypt = decrypt(encryptStr, privateKey);
System.out.println(decrypt);

123456abcd你好