SpringSecurity学习之自定义过滤器

　　我们系统中的认证场景通常比较复杂，比如说用户被锁定无法登录，限制登录IP等。而SpringSecuriy最基本的是基于用户与密码的形式进行认证，由此可知它的一套验证规范根本无法满足业务需要，因此扩展势在必行。那么我们可以考虑自己定义filter添加至SpringSecurity的过滤器栈当中，来实现我们自己的验证需要。

　　本例中，基于前篇的数据库的Student表来模拟一个简单的例子：当Student的jointime在当天之后，那么才允许登录

一、创建自己定义的Filter

我们先在web包下创建好几个包并定义如下几个类

CustomerAuthFilter:

package com.bdqn.lyrk.security.study.web.filter;

import com.bdqn.lyrk.security.study.web.authentication.UserJoinTimeAuthentication;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter;
import org.springframework.security.web.util.matcher.AntPathRequestMatcher;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class CustomerAuthFilter extends AbstractAuthenticationProcessingFilter {

    private AuthenticationManager authenticationManager;

    public CustomerAuthFilter(AuthenticationManager authenticationManager) {

        super(new AntPathRequestMatcher("/login", "POST"));
        this.authenticationManager = authenticationManager;

    }

    @Override
    public Authentication attemptAuthentication(HttpServletRequest request, HttpServletResponse response) throws AuthenticationException, IOException, ServletException {
        String username = request.getParameter("username");
        UserJoinTimeAuthentication usernamePasswordAuthenticationToken =new UserJoinTimeAuthentication(username);
        Authentication authentication = this.authenticationManager.authenticate(usernamePasswordAuthenticationToken);
        if (authentication != null) {
            super.setContinueChainBeforeSuccessfulAuthentication(true);
        }
        return authentication;
    }
}

　　该类继承AbstractAuthenticationProcessingFilter，这个filter的作用是对最基本的用户验证的处理，我们必须重写attemptAuthentication方法。Authentication接口表示授权接口，通常情况下业务认证通过时会返回一个这个对象。super.setContinueChainBeforeSuccessfulAuthentication(true) 设置成true的话，会交给其他过滤器处理。

二、定义UserJoinTimeAuthentication

package com.bdqn.lyrk.security.study.web.authentication;

import org.springframework.security.authentication.AbstractAuthenticationToken;

public class UserJoinTimeAuthentication extends AbstractAuthenticationToken {
    private String username;

    public UserJoinTimeAuthentication(String username) {
        super(null);
        this.username = username;
    }

    @Override
    public Object getCredentials() {
        return null;
    }

    @Override
    public Object getPrincipal() {
        return username;
    }
}

自定义授权方式，在这里接收username的值处理，其中getPrincipal我们可以用来存放登录名，getCredentials可以存放密码，这些方法来自于Authentication接口

三、定义AuthenticationProvider

package com.bdqn.lyrk.security.study.web.authentication;

import com.bdqn.lyrk.security.study.app.pojo.Student;
import org.springframework.security.authentication.AuthenticationProvider;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;

import java.util.Date;

/**
 * 基本的验证方式
 *
 * @author chen.nie
 * @date 2018/6/12
 **/
public class UserJoinTimeAuthenticationProvider implements AuthenticationProvider {
    private UserDetailsService userDetailsService;

    public UserJoinTimeAuthenticationProvider(UserDetailsService userDetailsService) {
        this.userDetailsService = userDetailsService;
    }

    /**
     * 认证授权，如果jointime在当前时间之后则认证通过
     * @param authentication
     * @return
     * @throws AuthenticationException
     */
    @Override
    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
        String username = (String) authentication.getPrincipal();
        UserDetails userDetails = this.userDetailsService.loadUserByUsername(username);
        if (!(userDetails instanceof Student)) {
            return null;
        }
        Student student = (Student) userDetails;
        if (student.getJoinTime().after(new Date()))
            return new UserJoinTimeAuthentication(username);
        return null;
    }

    /**
     * 只处理UserJoinTimeAuthentication的认证
     * @param authentication
     * @return
     */
    @Override
    public boolean supports(Class<?> authentication) {
        return authentication.getName().equals(UserJoinTimeAuthentication.class.getName());
    }
}

　　AuthenticationManager会委托AuthenticationProvider进行授权处理，在这里我们需要重写support方法，该方法定义Provider支持的授权对象，那么在这里我们是对UserJoinTimeAuthentication处理。

四、WebSecurityConfig

package com.bdqn.lyrk.security.study.app.config;

import com.bdqn.lyrk.security.study.app.service.UserService;
import com.bdqn.lyrk.security.study.web.authentication.UserJoinTimeAuthenticationProvider;
import com.bdqn.lyrk.security.study.web.filter.CustomerAuthFilter;
import org.springframework.beans.factory.annotation.Autowired;
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.web.authentication.UsernamePasswordAuthenticationFilter;

/**
 * spring-security的相关配置
 *
 * @author chen.nie
 * @date 2018/6/7
 **/
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    @Autowired
    private UserService userService;

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        /*
            1.配置静态资源不进行授权验证
            2.登录地址及跳转过后的成功页不需要验证
            3.其余均进行授权验证
         */
        http.
                authorizeRequests().antMatchers("/static/**").permitAll().
                and().authorizeRequests().antMatchers("/user/**").hasRole("7022").
                and().authorizeRequests().anyRequest().authenticated().
                and().formLogin().loginPage("/login").successForwardUrl("/toIndex").permitAll()
                .and().logout().logoutUrl("/logout").invalidateHttpSession(true).deleteCookies().permitAll()
        ;

        http.addFilterBefore(new CustomerAuthFilter(authenticationManager()), UsernamePasswordAuthenticationFilter.class);

    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        //设置自定义userService
        auth.userDetailsService(userService);
        auth.authenticationProvider(new UserJoinTimeAuthenticationProvider(userService));
    }

    @Override
    public void configure(WebSecurity web) throws Exception {
        super.configure(web);
    }
}

　　在这里面我们通过HttpSecurity的方法来添加我们自定义的filter，一定要注意先后顺序。在AuthenticationManagerBuilder当中还需要添加我们刚才定义的 AuthenticationProvider

启动成功后，我们将Student表里的jointime值改为早于今天的时间，进行登录可以发现：