CCS添加工程文件，并且配置环境
2026/6/8 3:22:10
1. SpringSecurity核心源码分析
分析SpringSecurity的核心原理，那么我们从哪开始分析？以及我们要分析哪些内容？
系统启动的时候SpringSecurity做了哪些事情？
第一次请求执行的流程是什么？
SpringSecurity中的认证流程是怎么样的？
1.1 系统启动
当我们的Web服务启动的时候，SpringSecurity做了哪些事情？当系统启动的时候，肯定会加载我们配置的web.xml文件
<!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 version="2.5" id="WebApp_ID" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <display-name>Archetype Created Web Application</display-name> <!-- 初始化spring容器 --> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <!-- post乱码过滤器 --> <filter> <filter-name>CharacterEncodingFilter</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> <filter-mapping> <filter-name>CharacterEncodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <!-- 前端控制器 --> <servlet> <servlet-name>dispatcherServletb</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <!-- contextConfigLocation不是必须的， 如果不配置contextConfigLocation， springmvc的配置文件默认在：WEB-INF/servlet的name+"-servlet.xml" --> <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>dispatcherServletb</servlet-name> <!-- 拦截所有请求jsp除外 --> <url-pattern>/</url-pattern> </servlet-mapping> <!-- 配置过滤器链 springSecurityFilterChain 名称固定 --> <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> </web-app>
web.xml中配置的信息：
Spring的初始化(会加载解析SpringSecurity的配置文件)
SpringMVC的前端控制器初始化
加载DelegatingFilterProxy过滤器
Spring的初始化操作和SpringSecurity有关系的操作是，会加载介绍SpringSecurity的配置文件，将相关的数据添加到Spring容器中
SpringMVC的初始化和SpringSecurity其实是没有多大关系的
DelegatingFilterProxy过滤器：拦截所有的请求。而且这个过滤器本身是和SpringSecurity没有关系的！！！在之前介绍Shiro的时候，和Spring整合的时候我们也是使用的这个过滤器。 其实就是完成从IoC容器中获取DelegatingFilterProxy这个过滤器配置的 FileterName 的对象。
系统启动的时候会执行DelegatingFilterProxy的init方法
protected void initFilterBean() throws ServletException { synchronized(this.delegateMonitor) { // 如果委托对象为null 进入 if (this.delegate == null) { // 如果targetBeanName==null if (this.targetBeanName == null) { // targetBeanName = 'springSecurityFilterChain' this.targetBeanName = this.getFilterName(); } // 获取Spring的容器对象 WebApplicationContext wac = this.findWebApplicationContext(); if (wac != null) { // 初始化代理对象 this.delegate = this.initDelegate(wac); } } } }protected Filter initDelegate(WebApplicationContext wac) throws ServletException { // springSecurityFilterChain String targetBeanName = this.getTargetBeanName(); Assert.state(targetBeanName != null, "No target bean name set"); // 从IoC容器中获取 springSecurityFilterChain的类型为Filter的对象 Filter delegate = (Filter)wac.getBean(targetBeanName, Filter.class); if (this.isTargetFilterLifecycle()) { delegate.init(this.getFilterConfig()); } return delegate; }init方法的作用是：从IoC容器中获取 FilterChainProxy的实例对象，并赋值给 DelegatingFilterProxy的delegate属性
1.2 第一次请求
客户发送请求会经过很多歌Web Filter拦截。
然后经过系统启动的分析，我们知道有一个我们定义的过滤器会拦截客户端的所有的请求。DelegatingFilterProxy
当用户请求进来的时候会被doFilter方法拦截
public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain) throws ServletException, IOException { Filter delegateToUse = this.delegate; if (delegateToUse == null) { // 如果 delegateToUse 为空 那么完成init中的初始化操作 synchronized(this.delegateMonitor) { delegateToUse = this.delegate; if (delegateToUse == null) { WebApplicationContext wac = this.findWebApplicationContext(); if (wac == null) { throw new IllegalStateException("No WebApplicationContext found: no ContextLoaderListener or DispatcherServlet registered?"); } delegateToUse = this.initDelegate(wac); } this.delegate = delegateToUse; } } this.invokeDelegate(delegateToUse, request, response, filterChain); }invokeDelegate
protected void invokeDelegate(Filter delegate, ServletRequest request, ServletResponse response, FilterChain filterChain) throws ServletException, IOException { // delegate.doFilter() FilterChainProxy delegate.doFilter(request, response, filterChain); }所以在此处我们发现DelegatingFilterProxy最终是调用的委托代理对象的doFilter方法
FilterChainProxy
过滤器链的代理对象：增强过滤器链(具体处理请求的过滤器还不是FilterChainProxy ) 根据客户端的请求匹配合适的过滤器链链来处理请求
public class FilterChainProxy extends GenericFilterBean { private static final Log logger = LogFactory.getLog(FilterChainProxy.class); private static final String FILTER_APPLIED = FilterChainProxy.class.getName().concat(".APPLIED"); // 过滤器链的集合 保存的有很多个过滤器链 一个过滤器链中包含的有多个过滤器 private List<SecurityFilterChain> filterChains; private FilterChainProxy.FilterChainValidator filterChainValidator; private HttpFirewall firewall; // ..... }// 处理用户请求 public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { boolean clearContext = request.getAttribute(FILTER_APPLIED) == null; if (clearContext) { try { request.setAttribute(FILTER_APPLIED, Boolean.TRUE); this.doFilterInternal(request, response, chain); } finally { SecurityContextHolder.clearContext(); request.removeAttribute(FILTER_APPLIED); } } else { this.doFilterInternal(request, response, chain); } }doFilterInternal
private void doFilterInternal(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { FirewalledRequest fwRequest = this.firewall.getFirewalledRequest((HttpServletRequest)request); HttpServletResponse fwResponse = this.firewall.getFirewalledResponse((HttpServletResponse)response); // 根据当前的请求获取对应的过滤器链 List<Filter> filters = this.getFilters((HttpServletRequest)fwRequest); if (filters != null && filters.size() != 0) { FilterChainProxy.VirtualFilterChain vfc = new FilterChainProxy.VirtualFilterChain(fwRequest, chain, filters); vfc.doFilter(fwRequest, fwResponse); } else { if (logger.isDebugEnabled()) { logger.debug(UrlUtils.buildRequestUrl(fwRequest) + (filters == null ? " has no matching filters" : " has an empty filter list")); } fwRequest.reset(); chain.doFilter(fwRequest, fwResponse); } }获取到了对应处理请求的过滤器链
SpringSecurity中处理请求的过滤器中具体处理请求的方法
public void doFilter(ServletRequest request, ServletResponse response) throws IOException, ServletException { if (this.currentPosition == this.size) { if (FilterChainProxy.logger.isDebugEnabled()) { FilterChainProxy.logger.debug(UrlUtils.buildRequestUrl(this.firewalledRequest) + " reached end of additional filter chain; proceeding with original chain"); } this.firewalledRequest.reset(); this.originalChain.doFilter(request, response); } else { ++this.currentPosition; Filter nextFilter = (Filter)this.additionalFilters.get(this.currentPosition - 1); if (FilterChainProxy.logger.isDebugEnabled()) { FilterChainProxy.logger.debug(UrlUtils.buildRequestUrl(this.firewalledRequest) + " at position " + this.currentPosition + " of " + this.size + " in additional filter chain; firing Filter: '" + nextFilter.getClass().getSimpleName() + "'"); } nextFilter.doFilter(request, response, this); } }主要过滤器的介绍
主要过滤器| ProcessOn免费在线作图,在线流程图,在线思维导图
ExceptionTranslationFilter
ExceptionTranslationFilter是我们看的过滤器链中的倒数第二个，作用是捕获倒数第一个过滤器抛出来的异常信息。
FilterSecurityInterceptor
做权限相关的内容
public void invoke(FilterInvocation fi) throws IOException, ServletException { if (fi.getRequest() != null && fi.getRequest().getAttribute("__spring_security_filterSecurityInterceptor_filterApplied") != null && this.observeOncePerRequest) { fi.getChain().doFilter(fi.getRequest(), fi.getResponse()); } else { if (fi.getRequest() != null && this.observeOncePerRequest) { fi.getRequest().setAttribute("__spring_security_filterSecurityInterceptor_filterApplied", Boolean.TRUE); } // 抛出异常 ExceptionTranslationFilter就会捕获异常 InterceptorStatusToken token = super.beforeInvocation(fi); try { fi.getChain().doFilter(fi.getRequest(), fi.getResponse()); } finally { super.finallyInvocation(token); } super.afterInvocation(token, (Object)null); } }ExceptionTranslationFilter 处理异常的代码
当用第二次提交 http://localhost:8082/login时 我们要关注的是 DefaultLoginPageGeneratingFilter 这个过滤器
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException { HttpServletRequest request = (HttpServletRequest)req; HttpServletResponse response = (HttpServletResponse)res; boolean loginError = this.isErrorPage(request); boolean logoutSuccess = this.isLogoutSuccess(request); if (!this.isLoginUrlRequest(request) && !loginError && !logoutSuccess) { // 正常的业务请求就直接放过 chain.doFilter(request, response); } else { // 需要跳转到登录页面的请求 String loginPageHtml = this.generateLoginPageHtml(request, loginError, logoutSuccess); // 直接响应登录页面 response.setContentType("text/html;charset=UTF-8"); response.setContentLength(loginPageHtml.getBytes(StandardCharsets.UTF_8).length); response.getWriter().write(loginPageHtml); } }generateLoginPageHtml
private String generateLoginPageHtml(HttpServletRequest request, boolean loginError, boolean logoutSuccess) { String errorMsg = "Invalid credentials"; if (loginError) { HttpSession session = request.getSession(false); if (session != null) { AuthenticationException ex = (AuthenticationException)session.getAttribute("SPRING_SECURITY_LAST_EXCEPTION"); errorMsg = ex != null ? ex.getMessage() : "Invalid credentials"; } } StringBuilder sb = new StringBuilder(); sb.append("<!DOCTYPE html>\n<html lang=\"en\">\n <head>\n <meta charset=\"utf-8\">\n <meta name=\"viewport\" content=\"width=device-width, initial-scale=1, shrink-to-fit=no\">\n <meta name=\"description\" content=\"\">\n <meta name=\"author\" content=\"\">\n <title>Please sign in</title>\n <link href=\"https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css\" rel=\"stylesheet\" integrity=\"sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M\" crossorigin=\"anonymous\">\n <link href=\"https://getbootstrap.com/docs/4.0/examples/signin/signin.css\" rel=\"stylesheet\" crossorigin=\"anonymous\"/>\n </head>\n <body>\n <div class=\"container\">\n"); String contextPath = request.getContextPath(); if (this.formLoginEnabled) { sb.append(" <form class=\"form-signin\" method=\"post\" action=\"" + contextPath + this.authenticationUrl + "\">\n <h2 class=\"form-signin-heading\">Please sign in</h2>\n" + createError(loginError, errorMsg) + createLogoutSuccess(logoutSuccess) + " <p>\n <label for=\"username\" class=\"sr-only\">Username</label>\n <input type=\"text\" id=\"username\" name=\"" + this.usernameParameter + "\" class=\"form-control\" placeholder=\"Username\" required autofocus>\n </p>\n <p>\n <label for=\"password\" class=\"sr-only\">Password</label>\n <input type=\"password\" id=\"password\" name=\"" + this.passwordParameter + "\" class=\"form-control\" placeholder=\"Password\" required>\n </p>\n" + this.createRememberMe(this.rememberMeParameter) + this.renderHiddenInputs(request) + " <button class=\"btn btn-lg btn-primary btn-block\" type=\"submit\">Sign in</button>\n </form>\n"); } if (this.openIdEnabled) { sb.append(" <form name=\"oidf\" class=\"form-signin\" method=\"post\" action=\"" + contextPath + this.openIDauthenticationUrl + "\">\n <h2 class=\"form-signin-heading\">Login with OpenID Identity</h2>\n" + createError(loginError, errorMsg) + createLogoutSuccess(logoutSuccess) + " <p>\n <label for=\"username\" class=\"sr-only\">Identity</label>\n <input type=\"text\" id=\"username\" name=\"" + this.openIDusernameParameter + "\" class=\"form-control\" placeholder=\"Username\" required autofocus>\n </p>\n" + this.createRememberMe(this.openIDrememberMeParameter) + this.renderHiddenInputs(request) + " <button class=\"btn btn-lg btn-primary btn-block\" type=\"submit\">Sign in</button>\n </form>\n"); } if (this.oauth2LoginEnabled) { sb.append("<h2 class=\"form-signin-heading\">Login with OAuth 2.0</h2>"); sb.append(createError(loginError, errorMsg)); sb.append(createLogoutSuccess(logoutSuccess)); sb.append("<table class=\"table table-striped\">\n"); Iterator var7 = this.oauth2AuthenticationUrlToClientName.entrySet().iterator(); while(var7.hasNext()) { Entry<String, String> clientAuthenticationUrlToClientName = (Entry)var7.next(); sb.append(" <tr><td>"); String url = (String)clientAuthenticationUrlToClientName.getKey(); sb.append("<a href=\"").append(contextPath).append(url).append("\">"); String clientName = HtmlUtils.htmlEscape((String)clientAuthenticationUrlToClientName.getValue()); sb.append(clientName); sb.append("</a>"); sb.append("</td></tr>\n"); } sb.append("</table>\n"); } sb.append("</div>\n"); sb.append("</body></html>"); return sb.toString(); }第一次请求的完整的流程
页面调试也可以验证我的推论