关于OAuth 2.0,请参见下面这两篇文章(墙裂推荐):

OAuth 2.0

Spring Security OAuth 2.0


纸上得来终觉浅,绝知此事要躬行。理论知识了解以后,最终还是要动手实践,不亲自做一遍永远不知道里面有多少坑。本节的重点是用Spring Security实现授权码模式。

1. maven依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion> <groupId>com.cjs.example</groupId>
<artifactId>cjs-oauth2-code-server</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging> <name>cjs-oauth2-code-server</name>
<description></description> <parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.2.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent> <properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties> <dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.security.oauth</groupId>
<artifactId>spring-security-oauth2</artifactId>
<version>2.3.3.RELEASE</version>
</dependency> <dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies> <build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build> </project>

2. 配置Security

package com.cjs.example.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.builders.WebSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.security.provisioning.InMemoryUserDetailsManager; @Configuration
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter { @Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
super.configure(auth);
// auth.inMemoryAuthentication().withUser("zhangsan").password("$2a$10$qsJ/Oy1RmUxFA.YtDT8RJ.Y2kU3U4z0jvd35YmiMOAPpD.nZUIRMC").roles("USER"); } @Override
public void configure(WebSecurity web) throws Exception {
super.configure(web);
} @Override
protected void configure(HttpSecurity http) throws Exception {
super.configure(http);
} @Bean
@Override
protected UserDetailsService userDetailsService() {
User.UserBuilder builder = User.builder();
UserDetails user = builder.username("zhangsan").password("$2a$10$GStfEJEyoSHiSxnoP3SbD.R8XRowP1QKOdi.N6/iFEwEJWTQqlSba").roles("USER").build();
UserDetails admin = builder.username("lisi").password("$2a$10$GStfEJEyoSHiSxnoP3SbD.R8XRowP1QKOdi.N6/iFEwEJWTQqlSba").roles("USER", "ADMIN").build();
return new InMemoryUserDetailsManager(user, admin);
} @Bean
public PasswordEncoder passwordEncoder() {
return new BCryptPasswordEncoder();
} public static void main(String[] args) {
BCryptPasswordEncoder bCryptPasswordEncoder = new BCryptPasswordEncoder();
System.out.println(bCryptPasswordEncoder.encode("123456"));
System.out.println(bCryptPasswordEncoder.encode("12345678"));
}
}

3. 配置授权服务器

package com.cjs.example.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.security.oauth2.config.annotation.configurers.ClientDetailsServiceConfigurer;
import org.springframework.security.oauth2.config.annotation.web.configuration.AuthorizationServerConfigurerAdapter;
import org.springframework.security.oauth2.config.annotation.web.configuration.EnableAuthorizationServer;
import org.springframework.security.oauth2.config.annotation.web.configurers.AuthorizationServerEndpointsConfigurer;
import org.springframework.security.oauth2.config.annotation.web.configurers.AuthorizationServerSecurityConfigurer; @Configuration
@EnableAuthorizationServer
public class AuthorizationServerConfig extends AuthorizationServerConfigurerAdapter { @Override
public void configure(AuthorizationServerSecurityConfigurer security) throws Exception {
super.configure(security);
} @Override
public void configure(ClientDetailsServiceConfigurer clients) throws Exception {
clients.inMemory()
.withClient("my-client-1")
.secret("$2a$10$0jyHr4rGRdQw.X9mrLkVROdQI8.qnWJ1Sl8ly.yzK0bp06aaAkL9W")
.authorizedGrantTypes("authorization_code", "refresh_token")
.scopes("all")
.redirectUris("http://www.baidu.com");
} @Override
public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception {
super.configure(endpoints);
} public static void main(String[] args) {
System.out.println(new org.apache.tomcat.util.codec.binary.Base64().encodeAsString("my-client-1:12345678".getBytes()));
System.out.println(java.util.Base64.getEncoder().encodeToString("my-client-1:12345678".getBytes()));
}
}

这里客户端的secret是12345678,存储的是加密后的值

4. 启动类

package com.cjs.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication
public class CjsOauth2CodeServerApplication { public static void main(String[] args) {
SpringApplication.run(CjsOauth2CodeServerApplication.class, args);
}
}

到目前为止,好像我们就做了两件事情:一、配置用户;二、注册客户端

现在,我们有两个用户(zhangsan和lisi)以及一个已注册的客户端(my-client-1)

接下来,用postman模拟客户端请求获取access_token

5. 协议端点

我们知道,在获取access_token之前需要用户授权,然后返回一个code,最后用code换access_token

在这个过程中涉及到三个服务器端点:授权端点、重定向端点、令牌端点

通过控制台看看启动日志可能会加深理解:

  .   ____          _            __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.0.3.RELEASE) 2018-06-26 09:44:09.575 INFO 6528 --- [ main] c.c.e.CjsOauth2CodeServerApplication : Starting CjsOauth2CodeServerApplication on USER-20170302XK with PID 6528 (E:\cjsworkspace\cjs-oauth2-example\cjs-oauth2-code-server\target\classes started by Administrator in E:\cjsworkspace\cjs-oauth2-example\cjs-oauth2-code-server)
2018-06-26 09:44:09.597 INFO 6528 --- [ main] c.c.e.CjsOauth2CodeServerApplication : No active profile set, falling back to default profiles: default
2018-06-26 09:44:09.762 INFO 6528 --- [ main] ConfigServletWebServerApplicationContext : Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@22635ba0: startup date [Tue Jun 26 09:44:09 CST 2018]; root of context hierarchy
2018-06-26 09:44:12.931 INFO 6528 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http)
2018-06-26 09:44:12.997 INFO 6528 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2018-06-26 09:44:12.998 INFO 6528 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.31
2018-06-26 09:44:13.200 INFO 6528 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2018-06-26 09:44:13.200 INFO 6528 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 3448 ms
2018-06-26 09:44:13.379 INFO 6528 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2018-06-26 09:44:13.379 INFO 6528 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2018-06-26 09:44:13.379 INFO 6528 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2018-06-26 09:44:13.379 INFO 6528 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2018-06-26 09:44:13.379 INFO 6528 --- [ost-startStop-1] .s.DelegatingFilterProxyRegistrationBean : Mapping filter: 'springSecurityFilterChain' to: [/*]
2018-06-26 09:44:13.380 INFO 6528 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Servlet dispatcherServlet mapped to [/]
2018-06-26 09:44:13.529 INFO 6528 --- [ main] .s.o.p.e.FrameworkEndpointHandlerMapping : Mapped "{[/oauth/authorize]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.security.oauth2.provider.endpoint.AuthorizationEndpoint.authorize(java.util.Map<java.lang.String, java.lang.Object>,java.util.Map<java.lang.String, java.lang.String>,org.springframework.web.bind.support.SessionStatus,java.security.Principal)
2018-06-26 09:44:13.530 INFO 6528 --- [ main] .s.o.p.e.FrameworkEndpointHandlerMapping : Mapped "{[/oauth/authorize],methods=[POST],params=[user_oauth_approval]}" onto public org.springframework.web.servlet.View org.springframework.security.oauth2.provider.endpoint.AuthorizationEndpoint.approveOrDeny(java.util.Map<java.lang.String, java.lang.String>,java.util.Map<java.lang.String, ?>,org.springframework.web.bind.support.SessionStatus,java.security.Principal)
2018-06-26 09:44:13.530 INFO 6528 --- [ main] .s.o.p.e.FrameworkEndpointHandlerMapping : Mapped "{[/oauth/token],methods=[POST]}" onto public org.springframework.http.ResponseEntity<org.springframework.security.oauth2.common.OAuth2AccessToken> org.springframework.security.oauth2.provider.endpoint.TokenEndpoint.postAccessToken(java.security.Principal,java.util.Map<java.lang.String, java.lang.String>) throws org.springframework.web.HttpRequestMethodNotSupportedException
2018-06-26 09:44:13.531 INFO 6528 --- [ main] .s.o.p.e.FrameworkEndpointHandlerMapping : Mapped "{[/oauth/token],methods=[GET]}" onto public org.springframework.http.ResponseEntity<org.springframework.security.oauth2.common.OAuth2AccessToken> org.springframework.security.oauth2.provider.endpoint.TokenEndpoint.getAccessToken(java.security.Principal,java.util.Map<java.lang.String, java.lang.String>) throws org.springframework.web.HttpRequestMethodNotSupportedException
2018-06-26 09:44:13.531 INFO 6528 --- [ main] .s.o.p.e.FrameworkEndpointHandlerMapping : Mapped "{[/oauth/check_token]}" onto public java.util.Map<java.lang.String, ?> org.springframework.security.oauth2.provider.endpoint.CheckTokenEndpoint.checkToken(java.lang.String)
2018-06-26 09:44:13.531 INFO 6528 --- [ main] .s.o.p.e.FrameworkEndpointHandlerMapping : Mapped "{[/oauth/confirm_access]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.security.oauth2.provider.endpoint.WhitelabelApprovalEndpoint.getAccessConfirmation(java.util.Map<java.lang.String, java.lang.Object>,javax.servlet.http.HttpServletRequest) throws java.lang.Exception
2018-06-26 09:44:13.531 INFO 6528 --- [ main] .s.o.p.e.FrameworkEndpointHandlerMapping : Mapped "{[/oauth/error]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.security.oauth2.provider.endpoint.WhitelabelErrorEndpoint.handleError(javax.servlet.http.HttpServletRequest)
2018-06-26 09:44:13.760 INFO 6528 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-06-26 09:44:14.019 INFO 6528 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@22635ba0: startup date [Tue Jun 26 09:44:09 CST 2018]; root of context hierarchy
2018-06-26 09:44:14.049 INFO 6528 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.servlet.error.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2018-06-26 09:44:14.049 INFO 6528 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.servlet.error.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2018-06-26 09:44:14.062 INFO 6528 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-06-26 09:44:14.063 INFO 6528 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-06-26 09:44:14.103 WARN 6528 --- [ main] ion$DefaultTemplateResolverConfiguration : Cannot find template location: classpath:/templates/ (please add some templates or check your Thymeleaf configuration)
2018-06-26 09:44:14.865 INFO 6528 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2018-06-26 09:44:14.901 INFO 6528 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path ''
2018-06-26 09:44:14.904 INFO 6528 --- [ main] c.c.e.CjsOauth2CodeServerApplication : Started CjsOauth2CodeServerApplication in 6.298 seconds (JVM running for 8.287)

5.1. 授权端点

请求

参数名称 描述
response_type 必填。将其值设置为code表示如果成功的话将收到一个授权码。
client_id 必填。客户端标识。
redirect_uri 可选。重定向URI虽然不是必须的,但是你的服务应该会需要它。而且,这个URL必须和授权服务端注册的redirect_id一致。
scope 可选。请求可能会有一个或多个scope值。授权服务器会把客户端请求的范围(scope)展示给用户看。
state 推荐。state参数用于应用存储特定的请求数据的可以防止CSRF攻击。授权服务器必须原封不动地将这个值返回给应用。

例如:

http://localhost:8080/oauth/authorize?response_type=code&client_id=my-client-1&redirect_uri=http://www.baidu.com&scope=all

响应

参数名称 描述
code 授权码,稍后用此授权码交换访问令牌
state 请求时带的state参数

例如:

https://www.baidu.com/?code=7Zudn6

5.2. 令牌端点

请求

参数名称 描述
grant_type 必填。参数值必须是"authorization_code"
code 必填。之前收到的授权码
redirect_uri 可能是必填的。如果授权请求的时候有redirect_uri,那么token请求的时候也必须带上这个参数,二者的值必须是一样的。
client_id 客户端标识,如果没有其它的客户端认证存在的话这个参数是必须的。

关于客户端认证补充一点

授权服务器可以通过HTTP Basic Auth方式对客户端进行认证,也可以通过在请求中加一个client_secret参数来对客户端进行认证。

不建议将客户端的secret直接作为参数放到client_secret中,而且这种方式下client_id和client_secret都是必填参数。

特别注意,用户(资源所有者)的用户名和密码跟客户端的用户名和密码(client_id、client_secret)不是一套,它们是两个东西。

那么,通过HTTP Basic Auth如何对客户端进行认证呢?客户端需要怎样传参呢?

需要在请求header中设置Authorization,它的值是Basic + 空格 + Base64加密后的client_id:secret

至于为什么,那是协议要求的,具体可以参考https://tools.ietf.org/html/rfc2617#page-5,格式如下:

例如:

POST /oauth/token HTTP/1.1
Content-Type: application/x-www-form-urlencoded
Authorization: Basic bXktY2xpZW50LTE6MTIzNDU2Nzg=
cache-control: no-cache
Postman-Token: baf729b9-f030-41c1-b6fb-d740b0c5c573
User-Agent: PostmanRuntime/7.1.1
Accept: */*
Host: localhost:8080
cookie: JSESSIONID=45EAF00C9829B9F569579DB08533D850; UISESSION=2A65FF6FC8C6BE415DE3C043E3EDAAA4
accept-encoding: gzip, deflate
content-length: 103
Connection: keep-alive grant_type=authorization_code&code=7Zudn6&redirect_uri=http%3A%2F%2Fwww.baidu.com&client_id=my-client-1

6. 客户端请求

直接在浏览器中输入以下地址,然后会跳到登录授权页面

http://localhost:8080/oauth/authorize?response_type=code&client_id=my-client-1&redirect_uri=http://www.baidu.com&scope=all

上面这两个页面都是默认自带的

授权成功以后重定向

有了授权码以后就可以换取access_token了

这个请求中唯一需要注意的一个参数就是Authorization,这是用于认证客户端的,本例中它是这样算出来的

public static void main(String[] args) {
System.out.println(new org.apache.tomcat.util.codec.binary.Base64().encodeAsString("my-client-1:12345678".getBytes()));
System.out.println(java.util.Base64.getEncoder().encodeToString("my-client-1:12345678".getBytes()));
}

所以,最终是Basic bXktY2xpZW50LTE6MTIzNDU2Nzg=

到此为止,我们只是获得了access_token,下一节将讲解如何配置资源服务器,以及客户端访问受保护的资源。

另外,本例中关于令牌的存储,以及客户端注册都是在内存中,实际生产过程中肯定是要存储到数据库中的,这一部分以后有时间再写吧!

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