Spring Security之默认的过滤器链及自定义Filter操作

Spring Security 过滤器链及自定义Filter

过滤器顺序从上到下

自定义 Filter

自定义的 Filter 建议继承 GenericFilterBean，本文示例：

package com.example.filter;
import org.springframework.web.filter.GenericFilterBean;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import java.io.IOException;
/**
 * @author 咸鱼
 * @date 2019-05-26 18:02
 */
public class BeforeLoginFilter extends GenericFilterBean {
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        System.out.println("在 UsernamePasswordAuthenticationFilter 前调用");
        chain.doFilter(request, response);
    }
}

配置自定义 Filter 在 Spring Security 过滤器链中的位置

配置很简单，本文示例：

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
                .authorizeRequests()
                .antMatchers("/").permitAll()
                .antMatchers("/user/**").hasAuthority("USER")
                .and()
                .formLogin().loginPage("/login").defaultSuccessUrl("/user")
                .and()
                .logout().logoutUrl("/logout").logoutSuccessUrl("/login");
        // 在 UsernamePasswordAuthenticationFilter 前添加 BeforeLoginFilter
        http.addFilterBefore(new BeforeLoginFilter(), UsernamePasswordAuthenticationFilter.class);
        // 在 CsrfFilter 后添加 AfterCsrfFilter
        http.addFilterAfter(new AfterCsrfFilter(), CsrfFilter.class);
    }

说明：

HttpSecurity 有三个常用方法来配置：

addFilterBefore(Filter filter, Class<? extends Filter> beforeFilter)

在 beforeFilter 之前添加 filter

addFilterAfter(Filter filter, Class<? extends Filter> afterFilter)

在 afterFilter 之后添加 filter

addFilterAt(Filter filter, Class<? extends Filter> atFilter)

在 atFilter 相同位置添加 filter， 此 filter 不覆盖 filter

通过在不同 Filter 的 doFilter() 方法中加断点调试，可以判断哪个 filter 先执行，从而判断 filter 的执行顺序 。

spring security添加自定义过滤器

1、定义自己的过滤器

2、指定位置，通过HttpSecurity的方法指定

定义过滤器

package com.qiudaozhang.springsecurity.filter;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
public class RequestHeadCheckFilter implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        var httpRequest = (HttpServletRequest) servletRequest;
        var httpResponse = (HttpServletResponse) servletResponse;
        String requestId = httpRequest.getHeader("Request-id");
        if(requestId == null || requestId.isBlank()) {
            httpResponse.setStatus(HttpServletResponse.SC_BAD_REQUEST);
            return;
        }
        filterChain.doFilter(servletRequest,servletResponse);
    }
}

package com.qiudaozhang.springsecurity.filter;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
public class RequestParamCheckFilter implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        var httpRequest = (HttpServletRequest) servletRequest;
        var httpResponse = (HttpServletResponse) servletResponse;
        String timestamp = httpRequest.getParameter("timestamp");
        if(timestamp == null || timestamp.isBlank()) {
            httpResponse.setStatus(HttpServletResponse.SC_FORBIDDEN);
            return;
        }
        filterChain.doFilter(servletRequest,servletResponse);
    }
}

指定位置

HttpSecurity中有两个方法，指定过滤器的位置，一个指定在谁前面，一个指定在谁后面。

   public HttpSecurity addFilterAfter(Filter filter, Class<? extends Filter> afterFilter) {
       this.comparator.registerAfter(filter.getClass(), afterFilter);
       return this.addFilter(filter);
   }
   public HttpSecurity addFilterBefore(Filter filter, Class<? extends Filter> beforeFilter) {
       this.comparator.registerBefore(filter.getClass(), beforeFilter);
       return this.addFilter(filter);
   }

package com.qiudaozhang.springsecurity.config;
import com.qiudaozhang.springsecurity.filter.RequestHeadCheckFilter;
import com.qiudaozhang.springsecurity.filter.RequestParamCheckFilter;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.web.authentication.www.BasicAuthenticationFilter;
@Configuration
public class ProjectConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.addFilterBefore(
                new RequestHeadCheckFilter(),
                BasicAuthenticationFilter.class
        )
                .addFilterAfter(new RequestParamCheckFilter(),BasicAuthenticationFilter.class)
                .authorizeRequests()
                .anyRequest()
                .permitAll();
    }
}

测试

准备一个端点测试

package com.qiudaozhang.springsecurity.controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HelloController {
    @GetMapping("hello")
    public String hello () {
        return "hello";
    }
}

当前没有传递timestamp参数，所以参照约定，过滤器直接给出403.

当前头部信息和参数信息都提供了，检测通过。

实际应用场景 检测相关的头部，参数等等信息日志过滤器，将所有请求的相关数据记录下来特殊的权限校验等等。

以上为个人经验，希望能给大家一个参考，也希望大家多多支持我们。