JWT 使用加密算法RS256 非对称加密解密

参考文档：

https://gist.github.com/ssippe/8fc11c4d7e766e66f06db0431dba3f0a
https://github.com/dvsekhvalnov/jose-jwt

https://mac-blog.org.ua/dotnet-core-firebase-jwt/

 

需要引用如下包： jose-jwt (version=2.5.0)、bouncycastle 版本不限

加密和解密方式为：私钥加密、公钥解密  

生成私钥、公钥可以利用openssl工具、也可以通过在线上工具生成

私钥：

-----begin private key-----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-----end private key-----

公钥：

-----begin public key-----
migfma0gcsqgsib3dqebaquaa4gnadcbiqkbgqdlucaxtv1omu216ofdy0p2yppr
lptlolgmqvpmgkxd/sab5rpx5otzo5fdwjeyax8n6yae0ddjd5lsmnghvviikoz2
wyi17dqrk6aymvbuxioqzead5vi8ritts7qpnh/abh/b/3xhhvwnxn40mddqxa3e
2yfek327kqy4tqtscwidaqab
-----end public key-----

核心代码：

        /// <summary>
        /// jwt-rs256 加密
        /// 私钥加密，公钥解密
        /// </summary>
        /// <param name="payload">负荷部分，存储使用的信息</param>
        /// <param name="privatekey">私钥</param>
        /// <returns></returns>
        public static string jwtencryptrs256(idictionary<string, object> payload, string privatekey)
        {
            //可以扩展header
            //var headers = new dictionary<string, object>()
            //{
            //     { "typ", "jwt" },
            //     { "cty", "jwt" },
            //     { "keyid", "111-222-333"}
            //};

            using (var rsa = getrsacryptoserviceprovider(privatekey, true)) //读取私钥
            {
                var token = jose.jwt.encode(payload, rsa, jose.jwsalgorithm.rs256);
                //var token = jose.jwt.encode(payload, rsa, jose.jwsalgorithm.rs256, headers);  //带header
                return token;
            }
        }

        /// <summary>
        /// jwt-rs256 解密
        /// </summary>
        /// <param name="token">要解密的token</param>
        /// <param name="publickey">公钥</param>
        /// <returns></returns>
        public static dictionary<string, object> jwtdecryptrs256(string token, string publickey)
        {
            try
            {
                using (var rsa = getrsacryptoserviceprovider(publickey, false)) //读取公钥
                {
                    var payload = jose.jwt.decode<dictionary<string, object>>(token, rsa);
                    return payload;
                }
            }
            catch (exception ex)
            {
                return null;
            }
        }


        /// <summary>
        /// 根据 私钥 or 公钥 返回参数
        /// </summary>
        /// <param name="key">私钥 or 公钥</param>
        /// <returns></returns>
        private static rsacryptoserviceprovider getrsacryptoserviceprovider(string key, bool isprivate)
        {
            try
            {
                rsaparameters rsaparams;
                if (isprivate)
                {
                    using (var sr = new stringreader(key))
                    {
                        // use bouncycastle to convert the key to rsa parameters
                        //需要引用包 bouncycastle
                        var pemreader = new pemreader(sr);
                        var keypair = pemreader.readobject() as rsaprivatecrtkeyparameters;
                        if (keypair == null)
                        {
                            //没有读到privatekey
                        }
                        rsaparams = dotnetutilities.torsaparameters(keypair);
                    }
                }
                else
                {
                    using (var sr = new stringreader(key))
                    {
                        var pemreader = new pemreader(sr);
                        var keypair = pemreader.readobject() as rsakeyparameters;
                        if (keypair == null)
                        {
                            //没有读到publickey
                        }
                        rsaparams = dotnetutilities.torsaparameters(keypair);
                    }
                }
                var rsa = new rsacryptoserviceprovider();
                rsa.importparameters(rsaparams);
                return rsa;
            }
            catch (exception ex)
            {
                throw;
            }

        }

测试：

        static void main(string[] args)
        {

            string publickey = file.readalltext(@"d:\square\openssl\bin\rsa_public_key.pem");
            string privatekey = file.readalltext(@"d:\square\openssl\bin\rsa_private_key.pem");

            int timestamp = timehelper.gettimestamp(datetime.utcnow.addseconds(5));  //时间戳 
            var payload = new dictionary<string, object>
            {
                {"iss","123456"},
                {"exp",timestamp}   //5s
            };
            var gettoken = josejwthelper.jwtencryptrs256(payload, privatekey);   //私钥加密
            console.writeline("加密结果：" + gettoken);
            console.writeline("....");

            var getvalue = josejwthelper.jwtdecryptrs256(gettoken, publickey);   //公钥解密
            console.writeline("解密结果：" + jsonconvert.serializeobject(getvalue));


        }

测试结果：