JWT 验证

JSON Web Token（JWT）是目前最流行的跨域身份验证解决方案。为了网络应用环境间传递声明而执行的一种基于JSON的开发标准（RFC 7519），

该token被设计为紧凑且安全的，特别适用于分布式站点的单点登陆（SSO）场景。JWT的声明一般被用来在身份提供者和服务提供者间传递被认证的用户身份信息，

JWT的组成

  下面是JWT的一段示例，分为三个部分，分别是头部（header），载荷（payload）}和签证（signature），他们之间用点隔开。

eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.
eyJpc3MiOiLmtYHmnIjml6Dlj4wiLCJleHAiOjE1NzExMDIxNTMsInN1YiI6InRlc3RKV1QiLCJhdWQiOiJVU0VSIiwiaWF0IjoiMjAxOS8xMC8xNSA5OjE1OjQzIiwiZGF0YSI6eyJuYW1lIjoiMTExIiwiYWdlIjoxMSwiYWRkcmVzcyI6Imh1YmVpIn19.
25IbZpAbSXBQsr2k3h0IzKRAC6z3OJTWg38VDtcEER8


1.使用nuget安装JWT（示例环境为  .net 4.5）

2.使用帮助类

     

   public class JwtHelp
        {

            //私钥  web.config中配置
            //"GQDstcKsx0NHjPOuXOYg5MbeJ1XT0uFiwDVvVBrk";
            private static string secret = "footmark";

            /// <summary>
            /// 生成JwtToken
            /// </summary>
            /// <param name="payload">不敏感的用户数据</param>
            /// <returns></returns>
            public static string SetJwtEncode()
            {

                //格式如下
                IDateTimeProvider provider = new UtcDateTimeProvider();
                var now = provider.GetNow();
                var unixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
                //过期时间
                var secondsSinceEpoch = Math.Round((now - unixEpoch).TotalSeconds);

                var payload = new Dictionary<string, object>
            {
                { "exp", secondsSinceEpoch+3600 },  //3600秒后过期
                { "username","admin" },
                { "password","123456" }
            };

                IJwtAlgorithm algorithm = new HMACSHA256Algorithm();
                IJsonSerializer serializer = new JsonNetSerializer();
                IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();
                IJwtEncoder encoder = new JwtEncoder(algorithm, serializer, urlEncoder);

                var token = encoder.Encode(payload, secret);
                return token;
            }

            /// <summary>
            /// 根据jwtToken  获取实体
            /// </summary>
            /// <param name="token">jwtToken</param>
            /// <returns></returns>
            public static string GetJwtDecode(string token)
            {
                try
                {
                    IJsonSerializer serializer = new JsonNetSerializer();
                    IDateTimeProvider provider = new UtcDateTimeProvider();
                    IJwtValidator validator = new JwtValidator(serializer, provider);
                    IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();
                    IJwtDecoder decoder = new JwtDecoder(serializer, validator, urlEncoder);

                  
                    //token为之前生成的字符串
                    var userInfo = decoder.DecodeToObject(token, secret, verify: true);
                    //此处json为IDictionary<string, object> 类型
                    string username = userInfo["username"].ToString();  //可获取当前用户名
                    return "OK";

                }
                catch (TokenExpiredException)
                {
                    Console.WriteLine("Token has expired");
                }
                catch (SignatureVerificationException)
                {
                    Console.WriteLine("Token has invalid signature");
                }
                catch (Exception)
                {

                }
                return "Error";
            }
        }