.Net Core 3.0认证组件之Cookie认证组件解析源码

接着上文.Net Core 认证系统源码解析,Cookie认证算是常用的认证模式,但是目前主流都是前后端分离,有点鸡肋但是,不考虑移动端的站点或者纯管理后台网站可以使用这种认证方式.注意:基于浏览器且不是前后端分离的架构(页面端具有服务端处理能力).移动端就不要考虑了,太麻烦.支持前后端分离前给移动端提供认证Api的一般采用JwtBearer认证,可以和IdentityServer4的password模式结合.很适用,但是id4的password模式各客户端必须绝对信任,因为要暴露用户名密码.适合做企业级下所有产品的认证.不支持除企业外的第三方调用.当然id4提供了其他模式.这是题外话.但是场景得介绍清楚.以免误导大家!

1、Cookie认证流程

引入核心认证组件之后,通过扩展的方式引入Cookie认证,微软采用链式编程,很优雅.Net Core的一大特点.

注入Cookie认证方案,指定Cookie认证参数,并指定Cookie认证处理器,先不介绍参数,看看处理器干了什么.

Cookie的核心认证方法,第一步如下:

一些必须的防重复执行操作,没截图,也不介绍了,安全工作,只贴核心代码.第一步,就是去读取客户端存在的cookie信息.

微软在Cookie认证参数中提供了接口,意味者你可以自定义读取Cookie内容的实现,他会把上下文和Cookie的名称传给你,这样就能定制获取Cookie内容的实现.接着解密Cookie内容

微软注入了Core的核心加密组件,大家自行百度,却采用微软默认的实现.所以客户端的cookie内容一般都以加密内容显示.

接着

拿到seesionId的cliam,关于claim不多说,自行百度.core新的身份模型.必须了解的内容.

cookie认证参数中你可以配置SessionStore,意味者你的session可以进行持久化管理,数据库还是redis还是分布式环境自行选择.应用场景是cookie过长,客户端无法存储,那么就可以通过配置这个SessionStore来实现.即分布式会话.微软也提供了扩展.

接着,cookie过期检测.

接着

上面的代码意味着cookie可以自动刷新.通过以下两个参数

如果读取到的客户端的cookie支持过期刷新,那么重新写入到客户端.

ok,如果没有在客户端读取到cookie内容,意味者cookie被清除,或者用户是第一次登陆,直接返回认证失败,如果成功,执行认证cookie校验认证上下文的方法

Events可以在AuthenticationSchemeOptions参数中配置

但是Cookie认证参数提供了默认实现

意味者你可以在注入Cookie认证服务的时候,自定义验证cookie结果的验证实现.

通过CookieAuthenticationOptions的Events属性进行注入.验证完毕,

判断上下文中的ShouldRenew参数,这个你可以根据业务需要执行刷新cookie的实现,最后返回认证结果.

整个流程到这里结束.

2、应用

构建登陆页面和首页,直接网上找了,代码如下:

using Microsoft.AspNetCore.Authentication;
using Microsoft.AspNetCore.Authentication.Cookies;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Claims;
using System.Text.Encodings.Web;
using System.Threading.Tasks;

namespace Core.Authentication.Test
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddControllers();
            //注入核心认证组件和cookie认证组件
            services.AddAuthentication(options =>
            {
                options.DefaultAuthenticateScheme = CookieAuthenticationDefaults.AuthenticationScheme;
                options.DefaultChallengeScheme = CookieAuthenticationDefaults.AuthenticationScheme;
            }).AddCookie();
        }

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            app.UseAuthentication();

            app.UseAuthorize();

            app.AddLoginHtml();

            app.AddUserInfoHtml();
        }

    }

    public static class CustomMiddleware
    {
        /// <summary>
        /// 登陆页面跳过认证组件
        /// </summary>
        /// <param name="app"></param>
        /// <returns></returns>
        public static IApplicationBuilder UseAuthorize(this IApplicationBuilder app)
        {
            return app.Use(async (context, next) =>
            {
                if (context.Request.Path == "/Account/Login")
                {
                    await next();
                }
                else
                {
                    var user = context.User;
                    if (user?.Identity?.IsAuthenticated ?? false)
                    {
                        await next();
                    }
                    else
                    {
                        await context.ChallengeAsync();
                    }
                }
            });
        }

        /// <summary>
        /// 注入登陆页面
        /// </summary>
        /// <param name="app"></param>
        /// <returns></returns>
        public static IApplicationBuilder AddLoginHtml(this IApplicationBuilder app)
        {
            return app.Map("/Account/Login", builder => builder.Run(async context =>
            {
                if (context.Request.Method == "GET")
                {
                    await context.Response.WriteHtmlAsync(async res =>
                    {
                        await res.WriteAsync($"<form method=\"post\">");
                        await res.WriteAsync($"<input type=\"hidden\" name=\"returnUrl\" value=\"{HttpResponseExtensions.HtmlEncode(context.Request.Query["ReturnUrl"])}\"/>");
                        await res.WriteAsync($"<div class=\"form-group\"><label>用户名：<input type=\"text\" name=\"userName\" class=\"form-control\"></label></div>");
                        await res.WriteAsync($"<div class=\"form-group\"><label>密码：<input type=\"password\" name=\"password\" class=\"form-control\"></label></div>");
                        await res.WriteAsync($"<button type=\"submit\" class=\"btn btn-default\">登录</button>");
                        await res.WriteAsync($"</form>");
                    });
                }
                else
                {
                    var userName = context.Request.Form["userName"];
                    var userPassword = context.Request.Form["password"];
                    if (!(userName == "admin" && userPassword == "admin"))
                    {
                        await context.Response.WriteHtmlAsync(async res =>
                        {
                            await res.WriteAsync($"<h1>用户名或密码错误。</h1>");
                            await res.WriteAsync("<a class=\"btn btn-default\" href=\"/Account/Login\">返回</a>");
                        });
                    }
                    else
                    {
                        //写入Cookie
                        var claimIdentity = new ClaimsIdentity("Cookie");
                        claimIdentity.AddClaim(new Claim(ClaimTypes.NameIdentifier,"1"));
                        claimIdentity.AddClaim(new Claim(ClaimTypes.Name, userName));
                        claimIdentity.AddClaim(new Claim(ClaimTypes.Email, "1@qq.com"));

                        var claimsPrincipal = new ClaimsPrincipal(claimIdentity);

                        await context.SignInAsync(CookieAuthenticationDefaults.AuthenticationScheme, claimsPrincipal);
                        if (string.IsNullOrEmpty(context.Request.Form["ReturnUrl"])) context.Response.Redirect("/");
                        else context.Response.Redirect(context.Request.Form["ReturnUrl"]);
                    }
                }
            }));
        }

        /// <summary>
        /// 注入用户信息页面
        /// </summary>
        /// <returns></returns>`  
        public static IApplicationBuilder AddUserInfoHtml(this IApplicationBuilder app)
        {
            return app.Map("/profile", builder => builder.Run(async context =>
            {
                await context.Response.WriteHtmlAsync(async res =>
                {
                    await res.WriteAsync($"<h1>你好，当前登录用户： {HttpResponseExtensions.HtmlEncode(context.User.Identity.Name)}</h1>");
                    await res.WriteAsync("<a class=\"btn btn-default\" href=\"/Account/Logout\">退出</a>");
                    await res.WriteAsync($"<h2>AuthenticationType：{context.User.Identity.AuthenticationType}</h2>");

                    await res.WriteAsync("<h2>Claims:</h2>");
                    await res.WriteTableHeader(new string[] { "Claim Type", "Value" },
                        context.User.Claims.Select(c => new string[] { c.Type, c.Value }));
                });
            }));
        }
    }

    public static class HttpResponseExtensions
    {
        public static async Task WriteHtmlAsync(this HttpResponse response, Func<HttpResponse, Task> writeContent)
        {
            var bootstrap = "<link rel=\"stylesheet\" href=\"https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css\" integrity=\"sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u\" crossorigin=\"anonymous\">";
            response.ContentType = "text/html";
            await response.WriteAsync($"<!DOCTYPE html><html lang=\"zh-CN\"><head><meta charset=\"UTF-8\">{bootstrap}</head><body><div class=\"container\">");
            await writeContent(response);
            await response.WriteAsync("</div></body></html>");
        }
        public static async Task WriteTableHeader(this HttpResponse response, IEnumerable<string> columns, IEnumerable<IEnumerable<string>> data)
        {
            await response.WriteAsync("<table class=\"table table-condensed\">");
            await response.WriteAsync("<tr>");
            foreach (var column in columns)
            {
                await response.WriteAsync($"<th>{HtmlEncode(column)}</th>");
            }
            await response.WriteAsync("</tr>");
            foreach (var row in data)
            {
                await response.WriteAsync("<tr>");
                foreach (var column in row)
                {
                    await response.WriteAsync($"<td>{HtmlEncode(column)}</td>");
                }
                await response.WriteAsync("</tr>");
            }
            await response.WriteAsync("</table>");
        }
        public static string HtmlEncode(string content) =>
            string.IsNullOrEmpty(content) ? string.Empty : HtmlEncoder.Default.Encode(content);
    }
}