修改让cas支持客户端自定义登陆页面----服务器篇-

 让CAS支持客户端自定义登陆页面——服务器篇- [De velopment]

2009-03-23

声明 时请以超形式标明文章原始出处和作者信息及本声明fallenlord.blogbus./logs/36907044.html

上篇《让CAS支持客户端自定义登陆页面——原理篇》讲述了一些修改的理论基础这篇讲解如何对C AS服务器端进行修改。

修改需要基于几个基本原则

1 . 不影响原有统一登陆界面功能

2. 客户端应尽量保持简单

3. 尽量保证原有功能的完整性和安全性

对于第三点 必须事先说明将登陆页面放到客户端本身就是降低了 CAS安全性这意味着作为服务向外发布的CAS服务器中的用户密码有可能由于客户端的不安全性而导致泄露整个CAS系统成为了一个“水桶形态”整个CAS体系的安全性将取决于所有客户端中安全性最低的一个。这也是CAS官方一直不推荐的方式。

接下来我们讲解服务器端修改的详细过程

首先修改/WEB-IN F/web.xml  为cas增加一个/remoteLogin的映射

<servl et-mappi ng>

<servlet-n ame>c as</s ervlet-n ame>

<url-pattern>/remoteLogin</url-pattern>

</servl et-mapping>

然后修改cas-servlet.xml文件 增加我们对/remoteLogin映射的处理 需要增加一个新流程<bean id="handlerMappingB" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMappi ng ">

<property name="mappings">

<props>

<prop key="/login">loginControl ler</prop>

<prop key="/remoteLogin">remoteControl ler</prop>

</props>

</property>

<property name="interceptors">

<l ist>

<ref bean="localeChangeInterceptor" />

</list>

</property>

</b ea n>

然后在cas-servlet.xml文件中添加我们上面所配置的remoteController的bean

<!--增加远程控制者 允许以/remote请求启动remote控制流程-->

<bean id="remoteLoginControl ler"class="org.springframework.webflow.executor.mvc.FlowController"p:flowExecutor-ref="remoteLoginFlowExecutor"p:defaultFlowId="remoteLogin-webflow">

<property name="argumentHandl er">

<bean class="org.springframework.webflow.executor.support.RequestParameterFlowExecutorArgumentHandler"p:flowExecutionKeyArgu mentName="lt"

p:defaultFlowId="remoteLogin-webflow" />

</property>

</b ea n>

<flow:executor id="remoteLoginFlowExecutor" registry-ref="remoteLoginFlowRegistry">

<flow:execution-attributes>

<flow:alwaysRedirectOnPause value="false"/>

</flow:execution-attributes>

</flow:executor>

<flow:registry id="remoteLoginFlowRegistry">

<flow:location path="/WEB-INF/remoteLogin-webflow.xml"/>

</flow:registry>

可以看到上面将请求指向了webflow配置文件/WEB-IN F/remoteLogin-webflow.xml文件 我们需要创建此文件并配置其成为我们所需的流程 以下是remoteLogin-webflow.xml全文

<?xml version="1 .0" encoding="UTF-8"?>

<flow xmlns=".springframework.org/schema/webflow"xmlns:xsi=".w3.org/2001/XMLSchema-instance"xsi :schemaLocation="

.springframework.org/schema/webflow

.springframework.org/schema/webflow/spring-webflow-1 .0.xsd">

<start-state idref="remoteLogin"/>

<!--远程登陆主要Action -->

<action-state id="remoteLogin">

<action bean="remoteLoginAction" />

<transition on="error" to="remoteCal lbackView" />

<transition on="submit" to="bindAndValidate" />

<transition on="checkTicketGrantingTicket" to="ticketGrantingTicketExistsCheck" />

</action-state>

<!--远程回调页面 主要以JavaScript的方式回传一些参数用 -->

<end-state id="remoteCal lbackView" view="remoteCallbackView" />

<decision-state id="ticketGrantingTicketExistsCheck">

<if test="${flowScope.ticketGrantingTicketId != nul l}" then="hasServiceCheck"else="gat ewayRequ estCh eck" />

</decision-state>

<decision-state id="gatewayRequestCheck">

<if test="${external Context.requestParameterMap['gateway'] != ''&amp;&amp; externalContext.re questParameterMap['gateway'] != null&amp;&amp; flowScope.service != nul l}" then="redirect" else="re moteCal lbackView" />

</decision-state>

<decision-state id="hasServiceCheck">

<if test="${flowScope.service != nul l}" then="generateServiceTicket" else="remoteCal lbackView"/>

</decision-state>

<!--

The "warn" action makes the determination of whether to redirect directly to the requested service or display the "confirmation" page to go back to the server.

-->

<decision-state id="warn">

<if test="${flowScope.warnCookieValue}" then="showWarningView" else="redirect" /></decision-state>

<action-state id="bindAndVal idate">

<action bean="authenticationViaFormAction" />

<transition on="success" to="submit" />

<transition on="error" to="remoteCal lbackView" />

</action-state>

<action-state id="submit">

<action bean="authenticationViaFormAction"method="submit" />

<transition on="warn" to="warn" />

<transition on="success" to="sendTicketGrantingTicket" />

<transition on="error" to="remoteCal lbackView" />

</action-state>

<action-state id="sendTicketGrantingTicket">

<action bean="sendTicketGrantingTicketAction" />

<transition on="success" to="serviceCheck" />

</action-state>

<decision-state id="serviceCheck">

<if test="${flowScope.service != nul l}" then="generateServiceTicket"else="remoteCal lbackView" />

</decision-state>

<action-state id="generateServiceTicket">

<action bean="generateServiceTicketAction" />

<transition on="success" to ="warn" />

<transition on="error" to="remoteCal lbackView" />

<transition on="gateway" to="redirect" />

</action-state>

<!--

The "showWarningView" end state is the end state for when the user has requested privacy settings (to be "warned") to be turned on. It delegates to a view defines in default_views.properties that display the "Please cl ick here to go to the service."message.

-->

<end-state id="showWarningView" view="casLoginConfirmView" />

<!--

The "redirect" end state al lows CAS to properly end the workflow whi le sti l l redirecting the user back to the service required.

-->

<end-state id="redirect" view="bean:dynamicRedirectViewSelector" />

<end-state id="viewServiceErrorView" view="viewServiceErrorView" />

<end-state id="viewServiceSsoErrorView" view="viewServiceSsoErrorView" />

<global-transitions>

<transition to="viewServiceErrorView" on-exception="org.springframework.webflow.execution.repository.NoSuchFlowExecuti onException" />

<transition to="viewServiceSsoErrorView" on-

exception="org.jasig.cas.services.UnauthorizedSsoServiceException" />

<transition to="viewServiceErrorView" on-exception="org.jasig.cas.services.UnauthorizedServiceException" />

</global-transitions>

</flow>

以上文件根据原login-webflow.xml文件修改黄色背景为修改部分。可以看到我们在流程中增加了 r emoteLogin Action节点和remoteCallback View节点 下面我们配置remoteLogin节点

在/WEB-IN F/cas-servlet.xml文件中增加remoteLoginAction配置

<bean id="remoteLoginAction"class=".baidu.cas.web.flow.RemoteLoginAction"p:argu mentExtractors-ref="argumentExtractors"p:warnCookieGenerator-ref="warnCookieGenerator"p:ticketGrantingTicketCookieGenerator-ref="ticketGrantingTicketCookieGenerator" />

同时创建com.baidu.cas.web.flow.RemoteLoginAction类

*

*远程登陆票据提供Action.

*根据InitialFlowSetupAction修改.

* 由于InitialFlowSetupAction为final类 因此只能将代码复制过来再进行修改.

*

* author GuoLin

*/publ ic class RemoteLoginAction extends AbstractAction {

/** CookieGenerator for the Warnings. */

NotNul l

private CookieRetrievingCookieGenerator warnCookieGenerator;

/** CookieGenerator for the TicketGrantingTickets. */

NotNul l private CookieRetrievingCookieGenerator ticketGrantingTicketCookieGenerator;/** Extractors for finding the service. */

NotEmpty private List<ArgumentExtractor> argumentExtractors;

/** Boolean to note whether we've set the values on the generators or not. */private boolean pathPopulated = false;protected Event doExecute(final RequestContext context) throws Exception {final HttpServletRequest request =WebUti ls.getHttpServletRequest(context);if (!this.pathPo pul ated) {final String contextPath = context.getExternal Context().getContextPath() ;final String cookiePath = StringUti ls.hasText(contextPath) ? contextPath : "/";logger.info("Setting path for cookies to: " +cookiePath);this.warnCookieGenerator.setCookiePath(cookiePath) ;this.ticketGrantingTicketCookieGenerator.setCookiePath(cookiePath);this.pathPopulated = true;

}context.getFlowScope().put("ticketGrantingTicketId",this.ticketGrantingTicketCookieGenerator.retrieveCookieValue(request)) ;context.getFlowScope().put("warnCookieValue",

Boolean.valueOf(this.warnCookieGenerator.retrieveCookieValue(request))) ;final Service service =WebUti ls.getService(this.argumentExtractors, context);if (service != nul l &&logger.isDebugEnabled()) {logger.debug("Placing service in FlowScope: " + service.getId());

}context.getFlowScope().put("service", service) ;

//客户端必须传递loginUrl参数过来否则无法确定登陆目标页面if (StringUti ls.hasText(request.getParameter("loginUrl"))) {context.getFlowScope().put("remoteLoginUrl", request.getParameter("loginUrl"));

} else {request.setAttribute("remoteLoginMessage", "loginUrl parameter must be supported.") ;return error();

}

//若参数包含submit则进行提交否则进行验证if (StringUti ls.hasText(request.getParameter("submit"))) {return result("submit");

} else {return result("checkTicketGrantingTicket");

}

}publ ic void setTicketGrantingTicketCookieGenerator(final CookieRetrievingCookieGenerator ticketGrantingTicketCookieGenerator) {this.ticketGrantingTicketCookieGenerator = ticketGrantingTicketCookieGenerator;

}publ ic void setWarnCookieGenerator(final CookieRetrievingCookieGenerator warnCookieGenerator) {this.warnCookieGenerator =warnCookieGenerator;

}publ ic void setArgumentExtractors(