Spring Security学习笔记之RememberMeAuthenticationFilter - py_xin的博客 - CSDN博客
RememberMeAuthenticationFilter的作用是, 当用户没有登录而直接访问资源时, 从cookie里找出用户的信息, 如果Spring Security能够识别出用户提供的remember me cookie, 用户将不必填写用户名和密码, 而是直接登录进入系统. 它先分析SecurityContext里有没有Authentication对象. 如果有, 则不做任何操作, 直接跳到下一个过滤器. 如果没有, 则检查request里有没有包含remember-me的cookie信息. 如果有, 则解析出cookie里的验证信息, 判断是否有权限.
它的基本配置如下:
<sec:http entry-point-ref="myAuthenticationEntryPoint"> ... <sec:custom-filter ref="rememberMeFilter" position="REMEMBER_ME_FILTER"/></sec:http> <sec:authentication-manager alias="authenticationManager"> <sec:authentication-provider ref="authenticationProvider"/> <sec:authentication-provider ref="rememberMeAuthenticationProvider"/></sec:authentication-manager> <bean id="loginAuthenticationFilter" class="org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter"> ... <property name="rememberMeServices" ref="tokenBasedRememberMeServices"></property></bean> <bean id="rememberMeAuthenticationProvider" class="org.springframework.security.authentication.RememberMeAuthenticationProvider"> <property name="key" value="000016aad72443b3b78af239a0b6bd7c"/></bean> <bean id="rememberMeFilter" class="org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter"> <property name="authenticationManager" ref="authenticationManager"></property> <property name="rememberMeServices" ref="tokenBasedRememberMeServices"></property></bean> <bean id="tokenBasedRememberMeServices" class="org.springframework.security.web.authentication.rememberme.TokenBasedRememberMeServices"> <property name="key" value="000016aad72443b3b78af239a0b6bd7c"></property> <property name="userDetailsService" ref="userService"></property></bean>注意几点:
1) 在authenticationManager里要加多一个authentication provider -- RememberMeAuthenticationProvider;
2) 要为UsernamePasswordAuthenticationFilter的rememberMeServices属性指定一个实例;
3) RememberMeAuthenticationProvider和TokenBasedRememberMeServices都要为它们的key属性指定一个唯一的值. 这个值可以用应用名加一个不少于36位长度的随机字符串. 这个key是用来识别当前应用的唯一值.
4) 在提交登录表单的时候, 一定要加多一个名的_spring_security_remember_me的参数(这个名字可以改), 值可以是"true", "yes", "on"或"1". 如下:
<form id="loginForm" method="POST" action="my_login"> 姓名: <input type="text" id="my_username" name="my_username"/><br> 密码: <input type="password" id="my_password" name="my_password"/> <input type="button" value="登录" οnclick="login()"/><br> <input id="_spring_security_remember_me" name="_spring_security_remember_me" type="checkbox" value="true"/> <label for="_spring_security_remember_me">Remember Me?</label></form>在Spring Security的过滤器链里, RememberMeAuthenticationFilter是排在UsernamePasswordAuthenticationFilter之后的. 在第一次登录时(如果勾选了remember me), 在验证信息正确后, AbstractAuthenticationProcessingFilter(UsernamePasswordAuthenticationFilter的父类)最后会调用一个叫successfulAuthentication()的方法:
protected void successfulAuthentication(HttpServletRequest request, HttpServletResponse response, Authentication authResult) throws IOException, ServletException { if (logger.isDebugEnabled()) { logger.debug("Authentication success. Updating SecurityContextHolder to contain: " + authResult); } SecurityContextHolder.getContext().setAuthentication(authResult); // 调用rememberMeServices的loginSuccess()方法. rememberMeServices.loginSuccess(request, response, authResult); // Fire event if (this.eventPublisher != null) { eventPublisher.publishEvent(new InteractiveAuthenticationSuccessEvent(authResult, this.getClass())); } successHandler.onAuthenticationSuccess(request, response, authResult);}这个方法会调用rememberMeService的loginSuccess()方法(所以之前我们要在配置文件了为UsernamePasswordAuthenticationFilter配上它的rememberMeService实例). loginSuccess()方法最后会调用onLoginSuccess()方法. 上面我们配置的rememberMeService的实例是TokenBasedRememberMeServices. 现在我们看看它的onLoginSuccess()方法:
public void onLoginSuccess(HttpServletRequest request, HttpServletResponse response, Authentication successfulAuthentication) { String username = retrieveUserName(successfulAuthentication); String password = retrievePassword(successfulAuthentication); // If unable to find a username and password, just abort as TokenBasedRememberMeServices is // unable to construct a valid token in this case. if (!StringUtils.hasLength(username)) { logger.debug("Unable to retrieve username"); return; } if (!StringUtils.hasLength(password)) { UserDetails user = getUserDetailsService().loadUserByUsername(username); password = user.getPassword(); if (!StringUtils.hasLength(password)) { logger.debug("Unable to obtain password for user: " + username); return; } } int tokenLifetime = calculateLoginLifetime(request, successfulAuthentication); long expiryTime = System.currentTimeMillis(); // SEC-949 expiryTime += 1000L* (tokenLifetime < 0 ? TWO_WEEKS_S : tokenLifetime); // 把用户名, cookie的过期时间, 登录密码和key组成一个字符串, 然后用MD5加密 String signatureValue = makeTokenSignature(expiryTime, username, password); // 把加密字符串放进cookie里, 然后返回给浏览器 setCookie(new String[] {username, Long.toString(expiryTime), signatureValue}, tokenLifetime, request, response); if (logger.isDebugEnabled()) { logger.debug("Added remember-me cookie for user '" + username + "', expiry: '" + new Date(expiryTime) + "'"); }}这个方法主设置了一个cookie在用户的浏览器上, 它包含一个Base64编码的字符串, 包含以下内容:
- 用户的名字;
- 过期的日期/时间;
- 一个MD5的加密字符串, 包括过期日期/时间, 用户名和密码;
- 应用的key值, 是在TokenBasedRememberMeServices实例的key属性中定义的.
这些内容将通过Base64加密然后组合成一个cookie的值存储在浏览器中以备后用.
此时, 在登录成功后, 我们可以从浏览器里看到返回的信息里多了一个名为SPRING_SECURITY_REMEMBER_ME_COOKIE的cookie信息.
在后面的每个请求里面, request对象里都会附上这个cookie信息,
即使我们登出了, 这个cookie信息还会继续存在,
接着, 如果我们不登录, 而是直接访问页面的话, 它会访问成功. 因为这个时候, RememberMeAuthenticationFilter过滤器将会检查cookie的内容并通过检查是否为一个认证过的remember-me cookie来认证用户.
RememberMeAuthenticationFilter的doFilter()方法如下:
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException { HttpServletRequest request = (HttpServletRequest) req; HttpServletResponse response = (HttpServletResponse) res; // 如果SecurityContext里没有包含Authentication对象 if (SecurityContextHolder.getContext().getAuthentication() == null) { // 从request里解析出SPRING_SECURITY_REMEMBER_ME_COOKIE的信息, 然后转成一个RememberMeAuthenticationToken对象 Authentication rememberMeAuth = rememberMeServices.autoLogin(request, response); if (rememberMeAuth != null) { // Attempt authenticaton via AuthenticationManager try { // 再判断rememberMeAuth对象里的key值是否与配置文件里的key值相同 rememberMeAuth = authenticationManager.authenticate(rememberMeAuth); // Store to SecurityContextHolder SecurityContextHolder.getContext().setAuthentication(rememberMeAuth); onSuccessfulAuthentication(request, response, rememberMeAuth); if (logger.isDebugEnabled()) { logger.debug("SecurityContextHolder populated with remember-me token: '" + SecurityContextHolder.getContext().getAuthentication() + "'"); } // Fire event if (this.eventPublisher != null) { eventPublisher.publishEvent(new InteractiveAuthenticationSuccessEvent( SecurityContextHolder.getContext().getAuthentication(), this.getClass())); } if (successHandler != null) { successHandler.onAuthenticationSuccess(request, response, rememberMeAuth); return; } } catch (AuthenticationException authenticationException) { if (logger.isDebugEnabled()) { logger.debug("SecurityContextHolder not populated with remember-me token, as " + "AuthenticationManager rejected Authentication returned by RememberMeServices: '" + rememberMeAuth + "'; invalidating remember-me token", authenticationException); } rememberMeServices.loginFail(request, response); onUnsuccessfulAuthentication(request, response, authenticationException); } } chain.doFilter(request, response); } else { if (logger.isDebugEnabled()) { logger.debug("SecurityContextHolder not populated with remember-me token, as it already contained: '" + SecurityContextHolder.getContext().getAuthentication() + "'"); } chain.doFilter(request, response); }}它首先解析出cookie里的remember-me信息, 然后从数据库拿出用户的信息, 再比较两个信息是否一致, 来完成验证.
这里要注意 authenticationManager.authenticate(rememberMeAuth) 这个方法, 它会轮流调用authenticationManager里所有的AuthenticationProvider来进行验证. 而只有RememberMeAuthenticationProvider才能验证remember-me信息, 所有上面的配置文件里, 我们要为authenticationManager配多一个authentication-provider的实例 -- RememberMeAuthenticationProvider.
---------------------------------------
浏览器里的cookie信息什么时候会消失:
1) cookie自动过期
2) 手动清除浏览器的cookie信息(关闭浏览器不会自动清除cookie)
3) 登录一次失败后, 之前cookie里的remember-me信息会消失. (这个估计是RequestCacheAwareFilter的原因, 具体原因以后再补充)
Original url: Access
Created at: 2019-08-08 15:58:52
Category: default
Tags: none
未标明原创文章均为采集，版权归作者所有，转载无需和我联系，请注明原出处，南摩阿彌陀佛，知识，不只知道，要得到
最新评论