最近阴差阳错的搞上了SpringSecurity3,因为是自己做的小系统,中间遇到了很多坑,基本每个坑都踩过了,网上也查了不少资料,发现有不少错误的,更是让我绕了一圈又一圈,现在把一些基本的东西总结一下。
先从整体上总结一下为什么使用SS,一般的,在不使用ss的情况下,我们基本会在每个业务方法执行前,插入一段用于验证权限的代码,从而判断当前用户是否有相应权限进行操作,这样做就会让业务方法和验证权限有了一个紧密的耦合;如果使用ss,我们就可以通过注解或者XML配置方式代替权限验证,使得业务和权限代码彻底分离,通过下图可以更形象的理解:
目前,权限管理采用最多的技术都是基于角色访问控制技术RBAC(Role
Based Access Control)。一般来说,提供如下功能:1,角色管理界面,由用户定义角色,给角色赋权限;2,用户角色管理界面,由用户给系统用户赋予角色。什么是RBAC,说到底其实就是五张表,权限表-权限角色对应表-角色表-角色用户对应表-用户表,比较常见。但是ss3默认支持的并不是这种模式,而是通过XML配置角色及用户的方式实现的权限验证等操作,所以需要我们去实现SS中一些接口,让其支持RBAC,下面开始搭建一套支持RBAC技术的SS框架:
(1)数据库相关表格:
1.用户表Users
CREATE TABLE `users` (
`password` varchar(255) default NULL,
`username` varchar(255) default NULL,
`uid` int(11) NOT NULL auto_increment,
PRIMARY KEY (`uid`)
)
2.角色表Roles
CREATE TABLE `roles` (
`rolename` varchar(255) default NULL,
`rid` int(11) NOT NULL auto_increment,
PRIMARY KEY (`rid`)
)
3 用户_角色表users_roles
CREATE TABLE `users_roles` (
--用户表的外键
`uid` int(11) default NULL,
--角色表的外键
`rid` int(11) default NULL,
`urid` int(11) ,
PRIMARY KEY (`urid`),
)
4.资源表resources
CREATE TABLE `resources` (
-- 权限所对应的url地址
`url` varchar(255) default NULL,
--权限所对应的编码,例201代表发表文章
`resourcename` varchar(255) default NULL,
`rsid` int(11) ,
PRIMARY KEY (`rsid`)
)
5.角色_资源表roles_resources
CREATE TABLE `roles_resources` (
`rsid` int(11) default NULL,
`rid` int(11) default NULL,
`rrid` int(11) NOT NULL ,
PRIMARY KEY (`rrid`),
)
(2)在继续配置前,需要知道ss是如何通过权限验证的,实际上ss通过拦截器,拦截发来的请求,对其进行验证的。而具体验证的方式则是通过我们实现相关接口的方法来进行的。既然是拦截器,web.xml势必是优先配置的。
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app>
<display-name>Archetype Created Web Application</display-name>
<!-- Spring Security配置 -->
<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!-- Spring MVC配置 -->
<servlet>
<servlet-name>spring</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-mvc.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>spring</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
<!-- Spring配置 -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
<!-- 指定Spring Bean的配置文件所在目录。默认配置在WEB-INF目录下 -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:applicationContext*.xml,classpath:spring-mybatis.xml</param-value>
</context-param>
<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<!-- Spring 刷新Introspector防止内存泄露 -->
<listener>
<listener-class>
org.springframework.web.util.IntrospectorCleanupListener
</listener-class>
</listener>
<!-- 获取Spring Security session的生命周期-->
<listener>
<listener-class>
org.springframework.security.web.session.HttpSessionEventPublisher
</listener-class>
</listener>
<!-- session超时定义,单位为分钟 -->
<session-config>
<session-timeout>20</session-timeout>
</session-config>
</web-app>
接下来是spring security3的一些配置,具体的每一个是什么意思,网上很多资料,这里不赘述了。总之,需要根据自己的需求,进行相应的修改。
<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/security"
xmlns:beans="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-3.2.xsd">
<http pattern="/css/**" security="none"></http>
<http pattern="/images/**" security="none"></http>
<http pattern="/img/**" security="none"></http>
<http pattern="/scripts/**" security="none"></http>
<http pattern="/font-awesome/**" security="none"></http>
<http pattern="/system/resources/**" security="none"></http>
<http pattern="/system/login.do" security="none"/>
<http auto-config="true" use-expressions="true">
<form-login login-page="/system/login.do" default-target-url="/system/sysManage.do"/>
<!--
error-if-maximum-exceeded 后登陆的账号会挤掉第一次登陆的账号
session-fixation-protection 防止伪造sessionid攻击,用户登录成功后会销毁用户当前的session。
-->
<!-- <session-management invalid-session-url="/user/timedout" session-fixation-protection="none">
<concurrency-control max-sessions="1" error-if-maximum-exceeded="true"/>
</session-management> -->
<custom-filter ref="myFilterSecurityInterceptor" before="FILTER_SECURITY_INTERCEPTOR"/>
</http>
<!-- 认证管理器,实现用户认证的入口,主要实现UserDetailsService接口即可 -->
<authentication-manager alias="authenticationManager">
<authentication-provider
user-service-ref="myUserDetailsServiceImpl">
<!-- <password-encoder hash="md5" /> --> <!--盐值 [添加这个属性后,加密密码明文为:"密码明文{盐值}"] -->
</authentication-provider>
</authentication-manager>
<!-- 配置过滤器 -->
<beans:bean id="myFilterSecurityInterceptor" class="com.product.sys.security.MyFilterSecurityInterceptor">
<!-- 用户是否拥有所请求资源的权限 -->
<beans:property name="accessDecisionManager" ref="myAccessDescisionManager" />
<!-- 资源与权限对应关系 -->
<beans:property name="fisMetadataSource" ref="mySecurityMetadataSource" />
<!-- 用户拥有的权限 -->
<beans:property name="authenticationManager" ref="authenticationManager" />
</beans:bean>
<beans:bean id="mySecurityMetadataSource" class="com.product.sys.security.MySecurityMetadataSource"><beans:constructor-arg name="userMapper" ref="userMapper"></beans:constructor-arg></beans:bean>
<beans:bean id="myAccessDescisionManager" class="com.product.sys.security.MyAccessDescisionManager"></beans:bean>
</beans:beans>
到上面的这个配置文件,则是重中之重了,和ss3打交道,主要都是这个文件。简单说一下,我们需要实现一个自己的filter,在配置中就是myFilterSecurityInterceptor,而这个filter中,还需要我们额外注入三个bean,分别是accessDecisionManager、fisMetadataSource以及authenticationManager,这三个属性中除了fisMetadataSource可以自定义名称外,其他两个都在ss3的父类中定义好了,所以此处需要特别注意,在这里掉过坑了。另外这里说一下这三个分别的作用,accessDecisionManager中有decide(Authentication authentication, Object object,Collection<ConfigAttribute> configAttributes)方法,该方法用于判断当前用户是否有权限进行操作,参数中authentication包含了当前用户所拥有的权限,configAttributes中包含了进行该步骤需要的权限,对其进行对比就可以判断该用户是否有权限进行操作。
/**
* @description 访问决策器,决定某个用户具有的角色,是否有足够的权限去访问某个资源 ;做最终的访问控制决定
*/
public class MyAccessDescisionManager implements AccessDecisionManager{
@Override
public void decide(Authentication authentication, Object object,
Collection<ConfigAttribute> configAttributes)
throws AccessDeniedException, InsufficientAuthenticationException {
// TODO Auto-generated method stub
System.out.println("MyAccessDescisionManager.decide()------------------验证用户是否具有一定的权限--------");
if(configAttributes==null) return;
Iterator<ConfigAttribute> it = configAttributes.iterator();
while(it.hasNext()){
String needResource = it.next().getAttribute();
//authentication.getAuthorities() 用户所有的权限
for(GrantedAuthority ga:authentication.getAuthorities()){
if(needResource.equals(ga.getAuthority())){
return;
}
}
}
throw new AccessDeniedException("--------MyAccessDescisionManager:decide-------权限认证失败!");
}
@Override
public boolean supports(ConfigAttribute attribute) {
// TODO Auto-generated method stub
return true;
}
@Override
public boolean supports(Class<?> clazz) {
// TODO Auto-generated method stub
return true;
}
}
到这里,可以很自然的想到是权限和用户数据从哪里得到的,filterInvocationSecurityMetadataSource在被加载时候,会首先将权限的信息建立起来,这里我用一个map,key为url,value为该权限的名称,这一步是在构造方法中进行的,也就是服务器启动时候完成的。而当用户访问某一个地址时,ss会到该类中调用getAttributes(Object obj)方法,obj中包含了访问的url地址,我们需要做的就是将该url对应的权限名称返回给ss,而ss会将返回的这个对象,其实就是accessDecisionManager的decide方法中的configAttributes对象。
/**
* @description 资源源数据定义,将所有的资源和权限对应关系建立起来,即定义某一资源可以被哪些角色访问
* @author aokunsang
* @date 2012-8-15
*/
public class MySecurityMetadataSource implements FilterInvocationSecurityMetadataSource {
private UserMapper userMapper;
public UserMapper getUserMapper() {
return userMapper;
}
public void setUserMapper(UserMapper userMapper) {
this.userMapper = userMapper;
}
/* 保存资源和权限的对应关系 key-资源url value-权限 */
private static Map<String,Collection<ConfigAttribute>> resourceMap = null;
private AntPathMatcher urlMatcher = new AntPathMatcher();
public MySecurityMetadataSource(UserMapper userMapper) {
this.userMapper = userMapper;
loadResourcesDefine();
}
@Override
public Collection<ConfigAttribute> getAllConfigAttributes() {
return null;
}
private void loadResourcesDefine(){
resourceMap = new HashMap<String,Collection<ConfigAttribute>>();
System.out.println("MySecurityMetadataSource.loadResourcesDefine()--------------开始加载资源列表数据--------");
List<RolePO> roles = userMapper.findAllRoles();
for(RolePO role : roles){
List<ResourcePO> resources = role.getResources();
for(ResourcePO resource : resources){
Collection<ConfigAttribute> configAttributes = null;
ConfigAttribute configAttribute = new SecurityConfig(resource.getResourceName());
if(resourceMap.containsKey(resource.getUrl())){
configAttributes = resourceMap.get(resource.getUrl());
configAttributes.add(configAttribute);
}else{
configAttributes = new ArrayList<ConfigAttribute>() ;
configAttributes.add(configAttribute);
resourceMap.put(resource.getUrl(), configAttributes);
}
}
}
System.out.println("11");
Set<String> set = resourceMap.keySet();
Iterator<String> it = set.iterator();
while(it.hasNext()){
String s = it.next();
System.out.println("key:"+s+"|value:"+resourceMap.get(s));
}
}
/*
* 根据请求的资源地址,获取它所拥有的权限
*/
@Override
public Collection<ConfigAttribute> getAttributes(Object obj)
throws IllegalArgumentException {
//获取请求的url地址
String url = ((FilterInvocation)obj).getRequestUrl();
System.out.println("MySecurityMetadataSource:getAttributes()---------------请求地址为:"+url);
Iterator<String> it = resourceMap.keySet().iterator();
while(it.hasNext()){
String _url = it.next();
if(_url.indexOf("?")!=-1){
_url = _url.substring(0, _url.indexOf("?"));
}
if(urlMatcher.match(_url,url)){
System.out.println("MySecurityMetadataSource:getAttributes()---------------需要的权限是:"+resourceMap.get(_url));
return resourceMap.get(_url);
}
}
Collection<ConfigAttribute> nouse = new ArrayList<ConfigAttribute>();
nouse.add(new SecurityConfig("无相应权限"));
return nouse;
}
@Override
public boolean supports(Class<?> arg0) {
System.out.println("MySecurityMetadataSource.supports()---------------------");
return true;
}
}
到这里,我们还有一个疑问,就是decide方法中的authentication对象(authentication.getAuthorities()包含当前用户拥有的权限),用户的对应角色和权限信息是从哪里获得的?其实这里是通过调用MyUserDetailsServiceImpl来获取的,该类需要实现UserDetailService接口,更具体一些实际上是通过loadUserByUsername进行获取用户权限信息的,这里注意返回的User不是我们自己定义的PO,而是ss3框架中的User。(这里说下为什么我自己的UserPO没有继承ss的User,就是因为User没有默认无参构造方法,导致mybatis无法创建对象,具体可能还是有办法的,比如重写mybatis的相关接口,比较麻烦,所以这里是先通过返回我们自己的UserPO后,再组装成ss需要的User对象进行的)这里在回到刚才AccessDescisionManager中的decide方法想一下,authentication.getAuthorities()其实获得的就是下面的Collection<GrantedAuthority>类型的对象。
最后下面的这段代码,我没有直接从username中直接获得resource,而是通过先获得role,再通过role获取resource,我感觉这样方便一些,sql也简单,当然有更好的可以替换掉。
@Component("myUserDetailsServiceImpl")
public class MyUserDetailsServiceImpl implements UserDetailsService{
@Resource
private UserMapper userMapper;
@Override
public UserDetails loadUserByUsername(String username)
throws UsernameNotFoundException {
System.out.println("username is " + username);
UserPO user = userMapper.getUserByUserName(username);
if(user == null) {
throw new UsernameNotFoundException(username);
}
Collection<GrantedAuthority> grantedAuths = obtionGrantedAuthorities(user);
System.out.println(user.getUsername());
return new User(
user.getUsername(),
user.getPassword(),
true,
true,
true,
true,
grantedAuths);
}
//取得用户的权限
private Set<GrantedAuthority> obtionGrantedAuthorities(UserPO user) {
Set<GrantedAuthority> authSet = new HashSet<GrantedAuthority>();
List<RolePO> roles = user.getRoles();
for(RolePO role : roles) {
RolePO innerRole = userMapper.getRoleByRoleName(role.getRoleName());
List<ResourcePO> tempRes = innerRole.getResources();
for(ResourcePO res : tempRes) {
authSet.add(new GrantedAuthorityImpl(res.getResourceName()));
}
}
return authSet;
}
}
到这里,所有的权限-角色-用户信息已经可以串起来了。再来梳理一下流程,启动服务器时,通过FilterInvocationSecurityMetadataSource获得用户的所有角色及权限信息,当用户登陆时,通过MyUserDetailsServiceImpl中的loadUserByUsername获得该登陆用户所有的权限,发出请求时,通过FilterInvocationSecurityMetadataSource的getAttributes(Object url)获得需要的权限名,最后在AccessDecisionManager中decide方法进行对比,如果用户拥有的权限名称和该url需要的权限名相同,那么放行,否则认证失败!清楚这些后,我们还需要一个filter,把上述流程串起来,就像提葡萄一样~
/**
* @description 一个自定义的filter,
* 必须包含authenticationManager,accessDecisionManager,securityMetadataSource三个属性,
我们的所有控制将在这三个类中实现
*/
public class MyFilterSecurityInterceptor extends AbstractSecurityInterceptor implements Filter{
private FilterInvocationSecurityMetadataSource fisMetadataSource;
/* (non-Javadoc)
* @see org.springframework.security.access.intercept.AbstractSecurityInterceptor#getSecureObjectClass()
*/
@Override
public Class<?> getSecureObjectClass() {
return FilterInvocation.class;
}
@Override
public SecurityMetadataSource obtainSecurityMetadataSource() {
return fisMetadataSource;
}
@Override
public void destroy() {}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("------------MyFilterSecurityInterceptor.doFilter()-----------开始拦截器了....");
FilterInvocation fi = new FilterInvocation(request, response, chain);
InterceptorStatusToken token = super.beforeInvocation(fi);
try {
fi.getChain().doFilter(fi.getRequest(), fi.getResponse());
} catch (Exception e) {
e.printStackTrace();
}finally{
super.afterInvocation(token,null);
}
System.out.println("------------MyFilterSecurityInterceptor.doFilter()-----------拦截器该方法结束了....");
}
@Override
public void init(FilterConfig config) throws ServletException {
}
public void setFisMetadataSource(
FilterInvocationSecurityMetadataSource fisMetadataSource) {
this.fisMetadataSource = fisMetadataSource;
}
public FilterInvocationSecurityMetadataSource getFisMetadataSource() {
return fisMetadataSource;
}
}
如果全部照搬上边的代码,到这里就已经结束了。
但是昨天晚上遇到一个大坑,就是发现如果我在数据库中配置了该用户的相关权限url后,用户可以访问,如果用户没有该url的权限,该用户依然可以访问url,这是让我无比吃惊,因为大部分都是参考网络的资料写的,后来看了一下ss的源码,才发现可能是其他人写错了。这里简单说一下,因为单位电脑没有ss的源码,主要问题出在MyFilterSecurityInterceptor中的doFilter方法:InterceptorStatusToken token = super.beforeInvocation(fi); 当ss在未匹配到url的权限时,即MySecurityMetadataSource中的getAttributes返回的对象为空时,该方法beforeInvocation直接return null,而实际decide方法在下方并未运行。
protected InterceptorStatusToken beforeInvocation(Object object) {
if (!getSecureObjectClass().isAssignableFrom(object.getClass())) {
.....
}
Collection<ConfigAttribute> attributes = this.obtainSecurityMetadataSource().getAttributes(object);
if (attributes == null || attributes.isEmpty()) {//此处判断MySecurityMetadataSource中的getAttributes返回的对象
if (rejectPublicInvocations) {
throw new IllegalArgumentException("Secure object invocation " + object +
" was denied as public invocations are not allowed via this interceptor. "
+ "This indicates a configuration error because the "
+ "rejectPublicInvocations property is set to 'true'");
}
if (debug) {
logger.debug("Public object - authentication not attempted");
}
publishEvent(new PublicInvocationEvent(object));
return null; // no further work post-invocation
}
if (debug) {
logger.debug("Secure object: " + object + "; Attributes: " + attributes);
}
if (SecurityContextHolder.getContext().getAuthentication() == null) {
credentialsNotFound(messages.getMessage("AbstractSecurityInterceptor.authenticationNotFound",
"An Authentication object was not found in the SecurityContext"), object, attributes);
}
Authentication authenticated = authenticateIfRequired();//实际运行decide方法的地方
// Attempt authorization
try {
this.accessDecisionManager.decide(authenticated, object, attributes);
}
catch (AccessDeniedException accessDeniedException) {
publishEvent(new AuthorizationFailureEvent(object, attributes, authenticated, accessDeniedException));
throw accessDeniedException;
}
if (debug) {
logger.debug("Authorization successful");
}
if (publishAuthorizationSuccess) {
publishEvent(new AuthorizedEvent(object, attributes, authenticated));
}
// Attempt to run as a different user
Authentication runAs = this.runAsManager.buildRunAs(authenticated, object, attributes);
if (runAs == null) {
if (debug) {
logger.debug("RunAsManager did not change Authentication object");
}
// no further work post-invocation
return new InterceptorStatusToken(SecurityContextHolder.getContext(), false, attributes, object);
} else {
if (debug) {
logger.debug("Switching to RunAs Authentication: " + runAs);
}
SecurityContext origCtx = SecurityContextHolder.getContext();
SecurityContextHolder.setContext(SecurityContextHolder.createEmptyContext());
SecurityContextHolder.getContext().setAuthentication(runAs);
// need to revert to token.Authenticated post-invocation
return new InterceptorStatusToken(origCtx, true, attributes, object);
}
}
在我看的所有BLOG中,当匹配不到时,全部返回了Null,而当我追到 super.beforeInvocation(fi)源码中时,发现当getAttributes返回null后,ss就会跳过AccessDecisionManager的decide方法,导致未进行判断!从而ss会让用户请求顺利的通过。之后,查了一下ss官方英文文档,如下描述:
Collection<ConfigAttribute> getAttributes(Object object) throws IllegalArgumentException
ConfigAttribute
s that apply to a given secure object.- Parameters:
object
- the object being secured- Returns:
- the attributes that apply to the passed in secured object. Should return an empty collection if there are no applicable attributes.
- Throws:
IllegalArgumentException
- if the passed object is not of a type supported by theSecurityMetadataSource
implementation
红色标出了,应当返回一个空的对象集合如果没有相应权限的时候。而其他blog文返回的是null,导致后续跳过了decide方法!所以我在MySecurityMetadataSource中的getAttributes中写的是:
Collection<ConfigAttribute> nouse = new ArrayList<ConfigAttribute>();
nouse.add(new SecurityConfig("无相应权限"));
return nouse;
这样当没有权限时,才可以正常拦截!现在博文抄来抄去,正确的还好,但凡有错误。。真是坑死人。
这里发下几个帮助比较大的供参考:
http://aokunsang.iteye.com/blog/1638558
http://blog.csdn.net/k10509806/article/details/6369131
和只允许登陆一次的具体方法,需要重写UserPO中的hashCode和equal方法。
http://flashing.iteye.com/blog/823666