ASP.NET Core 2.2 JWT AUTH

为什么需要JWT

• CORS+COOKIE认证无法进行跨根域传认证cookie导致登陆失败，这个问题暂时没有解决办法（2019-8-7），测试（EDGE DEV,EDGE 可以，但是CHROME没办法SET-cookie)
• 前后端分离，开发采用的是不同IP，基于headers传TOKEN扩展性更好

DOTNET 对于JWT的支持

头文件需要

using Microsoft.IdentityModel.Tokens; //生成jwt token
using Microsoft.AspNetCore.Authentication.JwtBearer; // jwt auth 认证，需要用negut包安装
using Microsoft.AspNetCore.Authorization; // 认证
using System.Security.Claims; // 声明身份
using Microsoft.IdentityModel.Tokens; //Tokens
using System.Text; //编码

jwt token 生成

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Authentication;
using Microsoft.IdentityModel.Tokens;
using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;

namespace authtest.Controllers
{
    [Route("[controller]/[action]")]
    public class JwtAuthController : Controller
    {
        public IActionResult Login()
        {
           var claims = new[]
            {
                new Claim(JwtRegisteredClaimNames.Sub,"test"),new Claim(JwtRegisteredClaimNames.Jti,Guid.NewGuid().ToString()),new Claim(ClaimTypes.Role,"user"),new Claim("org","true")
            };
            var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("test6666666666666666666"));
            var creds = new SigningCredentials(key,SecurityAlgorithms.HmacSha256);
   
            var token = new JwtSecurityToken(null,null,claims,expires: DateTime.Now.AddMinutes(30),signingCredentials: creds);
            var test = new JwtSecurityTokenHandler().WriteToken(token);
            return Json(test);

        }
    }
}

自定义策略验证方式（Policy = "")

/// <summary>
    /// 用户认证需求
    /// </summary>
    internal class UserRequirement : IAuthorizationRequirement
    {
        public string UserIdentity { get; private set; }

        public UserRequirement(string UserIdentityName)
        {
            UserIdentity = UserIdentityName;
        }
    }
    /// <summary>
    /// 使用的用户认证方法
    /// </summary>
    internal class UserAuthorizationHandler: AuthorizationHandler<UserRequirement>
    {
        protected override Task HandleRequirementAsync(AuthorizationHandlerContext context,UserRequirement requirement)
        {
            try
            {
                if (context.User.FindFirst(requirement.UserIdentity).Value.Equals("true"))
                {
                    context.Succeed(requirement);
                }
                else
                {
                    context.Fail();
                }                  
            }
            catch
            {
                context.Fail();
            }          
             return Task.CompletedTask;            
        }
    }

startUp.cs 服务里添加服务

services.AddAuthentication(x =>
            {
                x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
                x.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
            }).AddJwtBearer(option =>
            {
                option.TokenValidationParameters = new Microsoft.IdentityModel.Tokens.TokenValidationParameters
                {
                    IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("test6666666666666666666")),ValidateAudience = false,ValidateIssuer = false,ValidateIssuerSigningKey = true,// 签名校对
                    ValidateLifetime = true,// 时间校对
                };
            });

            services.AddAuthorization(options =>
            {
                options.AddPolicy("org",policy =>
                {
                    policy.Requirements.Add(new UserRequirement("org"));
                });
                options.AddPolicy("std",policy =>
                {
                    policy.Requirements.Add(new UserRequirement("std"));
                });
                options.AddPolicy("head",policy =>
                {
                    policy.Requirements.Add(new UserRequirement("head"));
                });
            });

最后只要再需要权限验证的接口上添加特性

[Authorize(Policy="{可以是org可以是std可以是head}")]