从零开始Spring Security (一)

摘要

本文将一步步从零开始，搭建并讨论Spring Security原理
本文代码能够在 https://github.com/markfredch... 中找到。
后续每篇文章相关代码会以分支的方式上传。

第一步

• Hello World Rest API

• 默认Spring Security保护

Maven配置

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.2.RELEASE</version>
    <relativePath/>
</parent>
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-security</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

Java Code

@SpringBootApplication
public class SpringSecurityDemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringSecurityDemoApplication.class, args);
    }
}

@RestController
@RequestMapping("/api")
class DemoRestController {
    @GetMapping("/hello")
    public String greeting() {
        return "Hello World";
    }
}

Demo

好了， 如此简单的代码。一个最基本的Rest API /api/hello已经开发完成，并被Spring Security经过Basic Auth进行保护。

➜  ~ curl http://localhost:8080/api/hello
{"timestamp":1489887539548,"status":401,"error":"Unauthorized","message":"Full authentication is required to access this resource","path":"/api/hello"}

➜  ~ curl http://user:6a3810c9-1ad7-4694-a617-0411fec20c60@localhost:8080/api/hello
Hello World

用户名密码在服务的启动Log中找。

2017-03-19 09:30:31.492  INFO 76011 --- [  restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-03-19 09:30:31.571  INFO 76011 --- [  restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-03-19 09:30:31.959  INFO 76011 --- [  restartedMain] b.a.s.AuthenticationManagerConfiguration : 

Using default security password: 6a3810c9-1ad7-4694-a617-0411fec20c60

2017-03-19 09:30:32.047  INFO 76011 --- [  restartedMain] o.s.s.web.DefaultSecurityFilterChain     : Creating filter chain: OrRequestMatcher [requestMatchers=[Ant [pattern='/css/**'], Ant [pattern='/js/**'], Ant [pattern='/images/**'], Ant [pattern='/webjars/**'], Ant [pattern='/**/favicon.ico'], Ant [pattern='/error']]], []
2017-03-19 09:30:32.234  INFO 76011 --- [  restartedMain] o.s.s.web.DefaultSecurityFilterChain     : Creating filter chain: Ant [pattern='/h2-console/**'], [org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter@e89b69d, org.springframework.security.web.context.SecurityContextPersistenceFilter@1932f51e, org.springframework.security.web.header.HeaderWriterFilter@65c2ab9f, org.springframework.security.web.authentication.logout.LogoutFilter@3d247454, org.springframework.security.web.authentication.www.BasicAuthenticationFilter@1e897c55, org.springframework.security.web.savedrequest.RequestCacheAwareFilter@75a44063, org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter@31201444, org.springframework.security.web.authentication.AnonymousAuthenticationFilter@160c32f9, org.springframework.security.web.session.SessionManagementFilter@507dd201, org.springframework.security.web.access.ExceptionTranslationFilter@21062771, org.springframework.security.web.access.intercept.FilterSecurityInterceptor@1f8069f6]

知识点

• spring-boot-starter-security 加上此依赖以后，Spring Boot会对app对一些最简单的安全配置。

• 默认Basic Auth的用户密码须要在app启动的日志寻找。

第二步

• 使用InMemoryAuthentication自定义用户访问

• API权限控制

• API中获取当前用户信息

添加WebSecurityConfiguration

@Configuration
@EnableGlobalMethodSecurity(prePostEnabled = true)
public class WebSecurityConfiguration extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.inMemoryAuthentication()
                .withUser("admin")
                .password("admin-password")
                .roles("ADMIN")
                .and()
                .withUser("guest")
                .password("guest-password")
                .roles("GUEST");

    }
}

SecurityUtils

public class SecurityUtils {
    public static String getCurrentUser() {
        SecurityContext securityContext = SecurityContextHolder.getContext();
        Authentication authentication = securityContext.getAuthentication();
        if (authentication != null && authentication.getPrincipal() instanceof User) {
            return ((User) authentication.getPrincipal()).getUsername();
        } else {
            return null;
        }
    }
}

API接口定义访问权限

@RestController
@RequestMapping("/api")
class DemoRestController {
    @GetMapping("/hello")
    @PreAuthorize("hasRole('ADMIN')")
    public String greeting() {
        return "Hello " + SecurityUtils.getCurrentUser();
    }
}

Demo

➜  ~ curl http://admin:admin-password@localhost:8080/api/hello
Hello admin
➜  ~ curl http://guest:guest-password@localhost:8080/api/hello
{"timestamp":1489904173901,"status":403,"error":"Forbidden","exception":"org.springframework.security.access.AccessDeniedException","message":"不容许访问","path":"/api/hello"}

知识点

• 当配置EnableGlobalMethodSecurity(prePostEnabled = true)时，Spring Security会启用方法权限控制。

• @PreAuthorize("hasRole('ADMIN')")方法权限控制。@PreAuthorize使用Spring Expression Language来描述方法权限。本例子为当用户有ADMIN权限时，才能访问。

• 当用户完成登陆以后，默认设置下用户信息会以org.springframework.security.core.userdetails.User保存在SecurityContextHolder中

第三步

• 添加一个公共API，此API不须要进行Security保护。例如用户注册。

WebSecurityConfiguration

在WebSecurityConfiguration中添加如下方法。

@Override
public void configure(WebSecurity web) throws Exception {
    web.ignoring()
            .antMatchers("/api/public/api");
}

DemoRestController

@RestController
@RequestMapping("/api")
class DemoRestController {
    @GetMapping("/hello")
    @PreAuthorize("hasRole('ADMIN')")
    public String greeting() {
        return "Hello " + SecurityUtils.getCurrentUser();
    }

    @GetMapping("/public/api")
    public String publicAPI() {
        return "this is public API";
    }
}

Demo

➜  ~ curl http://localhost:8080/api/public/api
this is public API