Envoy实现.NET架构的网关（四）集成IdentityServer4实现OAuth2认证

.NET网关与Gateway实战-Envoy与kong课程

什么是OAuth2认证

简单说，OAuth 就是一种授权机制。数据的所有者告诉系统，同意授权第三方应用进入系统，获取这些数据。系统从而产生一个短期的进入令牌（token），用来代替密码，供第三方应用使用。

而IdentityServer4就是一个开源的OAuth2认证系统。网关与IdentityServer4集成之后，我们可以避免为内部的每个微服务集成IdentityServer4，可以避免很多重复的工作，而这也是网关的一个重要优势。

新建IdentityServer4服务

1新增WebApi，并引用Nuget包IdentityServer4

2.新增校验证书，其中的证书文件通过openssl创建

2.1安装生成证书程序:https://slproweb.com/products/Win32OpenSSL.html（对应操作系统）

2.2找到openssl安装位置生成证书，Country Name (2 letter code) [AU]:跳过所有步骤

openssl req -newkey rsa:2048 -nodes -keyout chester.key -x509 -days 365 -out chester.cer

openssl pkcs12 -export -in chester.cer -inkey chester.key -out chester.pfx

3.新增配置信息

public class Config{public static IEnumerable<ApiResource> GetApiResources(){return new List<ApiResource>{new ApiResource("api1", "我的第一个API"){UserClaims ={JwtClaimTypes.Audience},Scopes = new List<string>{"api"},}};}public static IEnumerable<Client> GetClients(){return new List<Client>{new Client{ClientId="client",//定义客户端IDClientSecrets={new Secret("secret".Sha256())//定义客户端秘钥},AllowedGrantTypes = GrantTypes.ResourceOwnerPassword,//授权方式为用户密码模式授权，类型可参考GrantTypes枚举AllowedScopes={ "api" }//允许客户端访问的范围}};}public static IEnumerable<ApiScope> ApiScopes =>new ApiScope[] { new ApiScope("api") };public static IEnumerable<IdentityResource> GetIdentityResources(){return new IdentityResource[]{new IdentityResources.OpenId()};}}

4.注入IdentityServer4

public void ConfigureServices(IServiceCollection services){services.AddIdentityServer()//注册服务//.AddDeveloperSigningCredential().AddSigningCredential(new X509Certificate2("chester.pfx","123456") ).AddInMemoryApiResources(Config.GetApiResources())//配置类定义的授权范围.AddInMemoryClients(Config.GetClients())//配置类定义的授权客户端.AddInMemoryApiScopes(Config.ApiScopes).AddTestUsers(new List<TestUser> { new TestUser { Username = "Admin", Password = "123456", SubjectId = "001", IsActive = true } });//模拟测试用户，这里偷懒了，用户可以单独管理，最好不要直接在这里Newservices.AddControllers();}

5.开启IdentityServer4中间件

app.UseIdentityServer();//添加中间件

6.然后启动IdentityServer4服务

配置Envoy

我们需要用到Envoy的envoy.filters.http.jwt_authn，需要注意的有以下几点

Envoy的过滤器加载是自上而下的，因此我们需要将此过滤器放到envoy.filters.http.router前
另外我们需要在配置文件中配置jwt的jwks地址/.well-known/openid-configuration/jwks，jwks是JSON Web密钥集—一种用于共享公钥的JSON表示法，用于验证JWT签名
并且我们需要配置ids4服务的cluster。

具体配置如下，需要注意的地方已标红

admin:address:socket_address:protocol: TCPaddress: 0.0.0.0port_value: 9902
static_resources:listeners:- name: listener_0address:socket_address:protocol: TCPaddress: 0.0.0.0port_value: 10000filter_chains:- filters:- name: envoy.filters.network.http_connection_managertyped_config:"@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManagerscheme_header_transformation:scheme_to_overwrite: httpstat_prefix: ingress_httproute_config:name: local_routevirtual_hosts:- name: local_servicedomains: ["*"]routes:- match:prefix: "/"route:host_rewrite_literal: 192.168.43.94cluster: service_envoyproxy_iohttp_filters:- name: envoy.filters.http.jwt_authntyped_config:"@type": type.googleapis.com/envoy.extensions.filters.http.jwt_authn.v3.JwtAuthenticationproviders:jwt_provider:issuer: "http://192.168.43.94:7000"audiences:- "api1"forward: trueremote_jwks:http_uri:uri: "http://192.168.43.94:7000/.well-known/openid-configuration/jwks"cluster: jwtservertimeout: 5srules:- match:prefix: "/"requires:provider_name: jwt_provider- name: envoy.filters.http.routerclusters:- name: jwtserverconnect_timeout: 0.25stype: STRICT_DNSlb_policy: ROUND_ROBINload_assignment:cluster_name: jwtserverendpoints:- lb_endpoints:- endpoint:address:socket_address:address: 192.168.43.94port_value: 7000- name: service_envoyproxy_ioconnect_timeout: 30stype: strict_dns# Comment out the following line to test on v6 networksdns_lookup_family: V4_ONLYlb_policy: ROUND_ROBINload_assignment:cluster_name: service_envoyproxy_ioendpoints:- lb_endpoints:- endpoint:address:socket_address:address: 192.168.43.94port_value: 5000

启动envoy

docker run --rm -it -p 9902:9902 -p 10000:10000 -v D:/gateway/envoy/config/static/:/etc/envoy/ -v D:/gateway/envoy/logs:/logs envoyproxy/envoy-dev  -c /etc/envoy/envoy-jwt.yaml