[转]NET Core中实现一个Token base的身份认证

转载

mob604757044d68 2017-01-03 11:11:00

文章标签 json ide microsoft 身份认证 mvc 文章分类 运维

以前在web端的身份认证都是基于Cookie | Session的身份认证, 在没有更多的终端出现之前，这样做也没有什么问题，但在Web API时代，你所需要面对的就不止是浏览器了，还有各种客户端，这样就有了一个问题，这些客户端是不知道cookie是什么鬼的。 (cookie其实是浏览器搞出来的小猫腻，用来保持会话的，但HTTP本身是无状态的, 各种客户端能提供的无非也就是HTTP操作的API)

而基于Token的身份认证就是应对这种变化而生的，它更开放，安全性也更高。

基于Token的身份认证有很多种实现方式，但我们这里只使用微软提供的API。

接下来的例子将带领大家完成一个使用微软JwtSecurityTokenHandler完成一个基于beare token的身份认证。

注意：这种文章属于Step by step教程，跟着做才不至于看晕，下载完整代码分析代码结构才有意义。

前期准备

推荐使用VS2015 Update3作为你的IDE，下载地址：www.visualstudio.com
你需要安装.NET Core的运行环境以及开发工具，这里提供VS版：www.microsoft.com/net/core

创建项目

在VS中新建项目，项目类型选择ASP.NET Core Web Application(.NET Core), 输入项目名称为CSTokenBaseAuth

Coding

创建一些辅助类在项目根目录下创建一个文件夹Auth,并添加RSAKeyHelper.cs以及TokenAuthOption.cs两个文件

在RSAKeyHelper.cs中

using System.Security.Cryptography;namespace CSTokenBaseAuth.Auth { public class RSAKeyHelper { public static RSAParameters GenerateKey() { using (var key = new RSACryptoServiceProvider(2048)) { return key.ExportParameters(true); } } } }
在TokenAuthOption.cs中

using System;using Microsoft.IdentityModel.Tokens; namespace CSTokenBaseAuth.Auth { public class TokenAuthOption { public static string Audience { get; } = "ExampleAudience"; public static string Issuer { get; } = "ExampleIssuer"; public static RsaSecurityKey Key { get; } = new RsaSecurityKey(RSAKeyHelper.GenerateKey()); public static SigningCredentials SigningCredentials { get; } = new SigningCredentials(Key, SecurityAlgorithms.RsaSha256Signature); public static TimeSpan ExpiresSpan { get; } = TimeSpan.FromMinutes(20); } }

Startup.cs
在ConfigureServices中添加如下代码：

services.AddAuthorization(auth =>{ auth.AddPolicy("Bearer", new AuthorizationPolicyBuilder() .AddAuthenticationSchemes(JwtBearerDefaults.AuthenticationScheme‌) .RequireAuthenticatedUser().Build()); });

完整的代码应该是这样

public void ConfigureServices(IServiceCollection services){ // Add framework services. services.AddApplicationInsightsTelemetry(Configuration); // Enable the use of an [Authorize("Bearer")] attribute on methods and classes to protect. services.AddAuthorization(auth => { auth.AddPolicy("Bearer", new AuthorizationPolicyBuilder() .AddAuthenticationSchemes(JwtBearerDefaults.AuthenticationScheme‌) .RequireAuthenticatedUser().Build()); }); services.AddMvc(); }

在Configure方法中添加如下代码

app.UseExceptionHandler(appBuilder => { appBuilder.Use(async (context, next) => { var error = context.Features[typeof(IExceptionHandlerFeature)] as IExceptionHandlerFeature; //when authorization has failed, should retrun a json message to client if (error != null && error.Error is SecurityTokenExpiredException) { context.Response.StatusCode = 401; context.Response.ContentType = "application/json"; await context.Response.WriteAsync(JsonConvert.SerializeObject( new { authenticated = false, tokenExpired = true } )); } //when orther error, retrun a error message json to client else if (error != null && error.Error != null) { context.Response.StatusCode = 500; context.Response.ContentType = "application/json"; await context.Response.WriteAsync(JsonConvert.SerializeObject( new { success = false, error = error.Error.Message } )); } //when no error, do next. else await next(); }); });

这段代码主要是Handle Error用的，比如当身份认证失败的时候会抛出异常，而这里就是处理这个异常的。
接下来在相同的方法中添加如下代码，

app.UseExceptionHandler(appBuilder => { appBuilder.Use(async (context, next) => { var error = context.Features[typeof(IExceptionHandlerFeature)] as IExceptionHandlerFeature; //when authorization has failed, should retrun a json message to client if (error != null && error.Error is SecurityTokenExpiredException) { context.Response.StatusCode = 401; context.Response.ContentType = "application/json"; await context.Response.WriteAsync(JsonConvert.SerializeObject( new { authenticated = false, tokenExpired = true } )); } //when orther error, retrun a error message json to client else if (error != null && error.Error != null) { context.Response.StatusCode = 500; context.Response.ContentType = "application/json"; await context.Response.WriteAsync(JsonConvert.SerializeObject( new { success = false, error = error.Error.Message } )); } //when no error, do next. else await next(); }); });

应用JwtBearerAuthentication

app.UseJwtBearerAuthentication(new JwtBearerOptions { TokenValidationParameters = new TokenValidationParameters { IssuerSigningKey = TokenAuthOption.Key, ValidAudience = TokenAuthOption.Audience, ValidIssuer = TokenAuthOption.Issuer, ValidateIssuerSigningKey = true, ValidateLifetime = true, ClockSkew = TimeSpan.FromMinutes(0) } });

完整的代码应该是这样

using System;using Microsoft.AspNetCore.Builder; using Microsoft.AspNetCore.Hosting; using Microsoft.Extensions.Configuration; using Microsoft.Extensions.DependencyInjection; using Microsoft.Extensions.Logging; using Microsoft.AspNetCore.Authorization; using Microsoft.AspNetCore.Authentication.JwtBearer; using CSTokenBaseAuth.Auth; using Microsoft.AspNetCore.Diagnostics; using Microsoft.IdentityModel.Tokens; using Microsoft.AspNetCore.Http; using Newtonsoft.Json; namespace CSTokenBaseAuth { public class Startup { public Startup(IHostingEnvironment env) { var builder = new ConfigurationBuilder() .SetBasePath(env.ContentRootPath) .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true) .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true); if (env.IsEnvironment("Development")) { // This will push telemetry data through Application Insights pipeline faster, allowing you to view results immediately. builder.AddApplicationInsightsSettings(developerMode: true); } builder.AddEnvironmentVariables(); Configuration = builder.Build(); } public IConfigurationRoot Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container public void ConfigureServices(IServiceCollection services) { // Add framework services. services.AddApplicationInsightsTelemetry(Configuration); // Enable the use of an [Authorize("Bearer")] attribute on methods and classes to protect. services.AddAuthorization(auth => { auth.AddPolicy("Bearer", new AuthorizationPolicyBuilder() .AddAuthenticationSchemes(JwtBearerDefaults.AuthenticationScheme‌) .RequireAuthenticatedUser().Build()); }); services.AddMvc(); } // This method gets called by the runtime. Use this method to configure the HTTP request pipeline public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory) { loggerFactory.AddConsole(Configuration.GetSection("Logging")); loggerFactory.AddDebug(); app.UseApplicationInsightsRequestTelemetry(); app.UseApplicationInsightsExceptionTelemetry(); #region Handle Exception app.UseExceptionHandler(appBuilder => { appBuilder.Use(async (context, next) => { var error = context.Features[typeof(IExceptionHandlerFeature)] as IExceptionHandlerFeature; //when authorization has failed, should retrun a json message to client if (error != null && error.Error is SecurityTokenExpiredException) { context.Response.StatusCode = 401; context.Response.ContentType = "application/json"; await context.Response.WriteAsync(JsonConvert.SerializeObject( new { authenticated = false, tokenExpired = true } )); } //when orther error, retrun a error message json to client else if (error != null && error.Error != null) { context.Response.StatusCode = 500; context.Response.ContentType = "application/json"; await context.Response.WriteAsync(JsonConvert.SerializeObject( new { success = false, error = error.Error.Message } )); } //when no error, do next. else await next(); }); }); #endregion #region UseJwtBearerAuthentication app.UseJwtBearerAuthentication(new JwtBearerOptions { TokenValidationParameters = new TokenValidationParameters { IssuerSigningKey = TokenAuthOption.Key, ValidAudience = TokenAuthOption.Audience, ValidIssuer = TokenAuthOption.Issuer, ValidateIssuerSigningKey = true, ValidateLifetime = true, ClockSkew = TimeSpan.FromMinutes(0) } }); #endregion app.UseMvc(routes => { routes.MapRoute( name: "default", template: "{controller=Login}/{action=Index}"); }); } } }
在Controllers中新建一个Web API Controller Class，命名为TokenAuthController.cs。我们将在这里完成登录授权
在同文件下添加两个类，分别用来模拟用户模型，以及用户存储，代码应该是这样

public class User{ public Guid ID { get; set; } public string Username { get; set; } public string Password { get; set; } } public static class UserStorage { public static List<User> Users { get; set; } = new List<User> { new User {ID=Guid.NewGuid(),Username="user1",Password = "user1psd" }, new User {ID=Guid.NewGuid(),Username="user2",Password = "user2psd" }, new User {ID=Guid.NewGuid(),Username="user3",Password = "user3psd" } }; }

接下来在TokenAuthController.cs中添加如下方法

private string GenerateToken(User user, DateTime expires){ var handler = new JwtSecurityTokenHandler(); ClaimsIdentity identity = new ClaimsIdentity( new GenericIdentity(user.Username, "TokenAuth"), new[] { new Claim("ID", user.ID.ToString()) } ); var securityToken = handler.CreateToken(new SecurityTokenDescriptor { Issuer = TokenAuthOption.Issuer, Audience = TokenAuthOption.Audience, SigningCredentials = TokenAuthOption.SigningCredentials, Subject = identity, Expires = expires }); return handler.WriteToken(securityToken); }

该方法仅仅只是生成一个Auth Token,接下来我们来添加另外一个方法来调用它
在相同文件中添加如下代码

[HttpPost]public string GetAuthToken(User user) { var existUser = UserStorage.Users.FirstOrDefault(u => u.Username == user.Username && u.Password == user.Password); if (existUser != null) { var requestAt = DateTime.Now; var expiresIn = requestAt + TokenAuthOption.ExpiresSpan; var token = GenerateToken(existUser, expiresIn); return JsonConvert.SerializeObject(new { stateCode = 1, requertAt = requestAt, expiresIn = TokenAuthOption.ExpiresSpan.TotalSeconds, accessToken = token }); } else { return JsonConvert.SerializeObject(new { stateCode = -1, errors = "Username or password is invalid" }); } }

该文件完整的代码应该是这样

using System;using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Mvc; using Newtonsoft.Json; using System.IdentityModel.Tokens.Jwt; using System.Security.Claims; using System.Security.Principal; using Microsoft.IdentityModel.Tokens; using CSTokenBaseAuth.Auth; namespace CSTokenBaseAuth.Controllers { [Route("api/[controller]")] public class TokenAuthController : Controller { [HttpPost] public string GetAuthToken(User user) { var existUser = UserStorage.Users.FirstOrDefault(u => u.Username == user.Username && u.Password == user.Password); if (existUser != null) { var requestAt = DateTime.Now; var expiresIn = requestAt + TokenAuthOption.ExpiresSpan; var token = GenerateToken(existUser, expiresIn); return JsonConvert.SerializeObject(new { stateCode = 1, requertAt = requestAt, expiresIn = TokenAuthOption.ExpiresSpan.TotalSeconds, accessToken = token }); } else { return JsonConvert.SerializeObject(new { stateCode = -1, errors = "Username or password is invalid" }); } } private string GenerateToken(User user, DateTime expires) { var handler = new JwtSecurityTokenHandler(); ClaimsIdentity identity = new ClaimsIdentity( new GenericIdentity(user.Username, "TokenAuth"), new[] { new Claim("ID", user.ID.ToString()) } ); var securityToken = handler.CreateToken(new SecurityTokenDescriptor { Issuer = TokenAuthOption.Issuer, Audience = TokenAuthOption.Audience, SigningCredentials = TokenAuthOption.SigningCredentials, Subject = identity, Expires = expires }); return handler.WriteToken(securityToken); } } public class User { public Guid ID { get; set; } public string Username { get; set; } public string Password { get; set; } } public static class UserStorage { public static List<User> Users { get; set; } = new List<User> { new User {ID=Guid.NewGuid(),Username="user1",Password = "user1psd" }, new User {ID=Guid.NewGuid(),Username="user2",Password = "user2psd" }, new User {ID=Guid.NewGuid(),Username="user3",Password = "user3psd" } }; } }
接下来我们来完成授权验证部分
在Controllers中新建一个Web API Controller Class，命名为ValuesController.cs
在其中添加如下代码

public string Get(){ var claimsIdentity = User.Identity as ClaimsIdentity; var id = claimsIdentity.Claims.FirstOrDefault(c => c.Type == "ID").Value; return $"Hello! {HttpContext.User.Identity.Name}, your ID is:{id}"; }

为方法添加装饰属性

[HttpGet][Authorize("Bearer")]
完整的文件代码应该是这样

using System.Linq;using Microsoft.AspNetCore.Mvc; using Microsoft.AspNetCore.Authorization; using System.Security.Claims; namespace CSTokenBaseAuth.Controllers { [Route("api/[controller]")] public class ValuesController : Controller { [HttpGet] [Authorize("Bearer")] public string Get() { var claimsIdentity = User.Identity as ClaimsIdentity; var id = claimsIdentity.Claims.FirstOrDefault(c => c.Type == "ID").Value; return $"Hello! {HttpContext.User.Identity.Name}, your ID is:{id}"; } } }
最后让我们来添加视图
在Controllers中新建一个Web Controller Class，命名为LoginController.cs
其中的代码应该是这样

using Microsoft.AspNetCore.Mvc;namespace CSTokenBaseAuth.Controllers { [Route("[controller]/[action]")] public class LoginController : Controller { public IActionResult Index() { return View(); } } }

在项目Views目录下新建一个名为Login的目录，并在其中新建一个Index.cshtml文件。
代码应该是这个样子

<html xmlns="http://www.w3.org/1999/xhtml"><head> <title></title> </head> <body> <button id="getToken">getToken</button> <button id="requestAPI">requestAPI</button> <script src="https://code.jquery.com/jquery-3.1.1.min.js"></script> <script> $(function () { var accessToken = undefined; $("#getToken").click(function () { $.post( "/api/TokenAuth", { Username: "user1", Password: "user1psd" }, function (data) { console.log(data); if (data.stateCode == 1) { accessToken = data.accessToken; $.ajaxSetup({ headers: { "Authorization": "Bearer " + accessToken } }); } }, "json" ); }) $("#requestAPI").click(function () { $.get("/api/Values", {}, function (data) { alert(data); }, "text"); }) }) </script> </body> </html>