Package org.springframework.security.cas.web

Class CasAuthenticationFilter

java.lang.Object
org.springframework.web.filter.GenericFilterBean
org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter
org.springframework.security.cas.web.CasAuthenticationFilter
All Implemented Interfaces:
jakarta.servlet.Filter, org.springframework.beans.factory.Aware, org.springframework.beans.factory.BeanNameAware, org.springframework.beans.factory.DisposableBean, org.springframework.beans.factory.InitializingBean, org.springframework.context.ApplicationEventPublisherAware, org.springframework.context.EnvironmentAware, org.springframework.context.MessageSourceAware, org.springframework.core.env.EnvironmentCapable, org.springframework.web.context.ServletContextAware
public class CasAuthenticationFilter extends AbstractAuthenticationProcessingFilter
Processes a CAS service ticket, obtains proxy granting tickets, and processes proxy tickets.

Service Tickets

A service ticket consists of an opaque ticket string. It arrives at this filter by the user's browser successfully authenticating using CAS, and then receiving a HTTP redirect to a service. The opaque ticket string is presented in the ticket request parameter.

This filter monitors the service URL so it can receive the service ticket and process it. By default this filter processes the URL /login/cas. When processing this URL, the value of ServiceProperties.getService() is used as the service when validating the ticket. This means that it is important that ServiceProperties.getService() specifies the same value as the filterProcessesUrl.

Processing the service ticket involves creating a CasServiceTicketAuthenticationToken which uses CasServiceTicketAuthenticationToken.CAS_STATEFUL_IDENTIFIER for the principal and the opaque ticket string as the credentials.

Obtaining Proxy Granting Tickets

If specified, the filter can also monitor the proxyReceptorUrl. The filter will respond to requests matching this url so that the CAS Server can provide a PGT to the filter. Note that in addition to the proxyReceptorUrl a non-null proxyGrantingTicketStorage must be provided in order for the filter to respond to proxy receptor requests. By configuring a shared ProxyGrantingTicketStorage between the TicketValidator and the CasAuthenticationFilter one can have the CasAuthenticationFilter handle the proxying requirements for CAS.

Proxy Tickets

The filter can process tickets present on any url. This is useful when wanting to process proxy tickets. In order for proxy tickets to get processed ServiceProperties.isAuthenticateAllArtifacts() must return true. Additionally, if the request is already authenticated, authentication will not occur. Last, AuthenticationDetailsSource.buildDetails(Object) must return a ServiceAuthenticationDetails. This can be accomplished using the ServiceAuthenticationDetailsSource. In this case ServiceAuthenticationDetails.getServiceUrl() will be used for the service url.

Processing the proxy ticket involves creating a CasServiceTicketAuthenticationToken which uses CasServiceTicketAuthenticationToken.CAS_STATELESS_IDENTIFIER for the principal and the opaque ticket string as the credentials. When a proxy ticket is successfully authenticated, the FilterChain continues and the authenticationSuccessHandler is not used.

Notes about the AuthenticationManager

The configured AuthenticationManager is expected to provide a provider that can recognise CasServiceTicketAuthenticationTokens containing this special principal name, and process them accordingly by validation with the CAS server. Additionally, it should be capable of using the result of ServiceAuthenticationDetails.getServiceUrl() as the service when validating the ticket.

Example Configuration

An example configuration that supports service tickets, obtaining proxy granting tickets, and proxy tickets is illustrated below: 

 <b:bean id="serviceProperties"
     class="org.springframework.security.cas.ServiceProperties"
     p:service="https://service.example.com/cas-sample/login/cas"
     p:authenticateAllArtifacts="true"/>
 <b:bean id="casEntryPoint"
     class="org.springframework.security.cas.web.CasAuthenticationEntryPoint"
     p:serviceProperties-ref="serviceProperties" p:loginUrl="https://login.example.org/cas/login" />
 <b:bean id="casFilter"
     class="org.springframework.security.cas.web.CasAuthenticationFilter"
     p:authenticationManager-ref="authManager"
     p:serviceProperties-ref="serviceProperties"
     p:proxyGrantingTicketStorage-ref="pgtStorage"
     p:proxyReceptorUrl="/login/cas/proxyreceptor">
     <b:property name="authenticationDetailsSource">
         <b:bean class="org.springframework.security.cas.web.authentication.ServiceAuthenticationDetailsSource"/>
     </b:property>
     <b:property name="authenticationFailureHandler">
         <b:bean class="org.springframework.security.web.authentication.SimpleUrlAuthenticationFailureHandler"
             p:defaultFailureUrl="/casfailed.jsp"/>
     </b:property>
 </b:bean>
 <!--
     NOTE: In a real application you should not use an in memory implementation. You will also want
           to ensure to clean up expired tickets by calling ProxyGrantingTicketStorage.cleanup()
  -->
 <b:bean id="pgtStorage" class="org.apereo.cas.client.proxy.ProxyGrantingTicketStorageImpl"/>
 <b:bean id="casAuthProvider" class="org.springframework.security.cas.authentication.CasAuthenticationProvider"
     p:serviceProperties-ref="serviceProperties"
     p:key="casAuthProviderKey">
     <b:property name="authenticationUserDetailsService">
         <b:bean
             class="org.springframework.security.core.userdetails.UserDetailsByNameServiceWrapper">
             <b:constructor-arg ref="userService" />
         </b:bean>
     </b:property>
     <b:property name="ticketValidator">
         <b:bean
             class="org.apereo.cas.client.validation.Cas20ProxyTicketValidator"
             p:acceptAnyProxy="true"
             p:proxyCallbackUrl="https://service.example.com/cas-sample/login/cas/proxyreceptor"
             p:proxyGrantingTicketStorage-ref="pgtStorage">
             <b:constructor-arg value="https://login.example.org/cas" />
         </b:bean>
     </b:property>
     <b:property name="statelessTicketCache">
         <b:bean class="org.springframework.security.cas.authentication.EhCacheBasedTicketCache">
             <b:property name="cache">
                 <b:bean class="net.sf.ehcache.Cache"
                   init-method="initialise"
                   destroy-method="dispose">
                     <b:constructor-arg value="casTickets"/>
                     <b:constructor-arg value="50"/>
                     <b:constructor-arg value="true"/>
                     <b:constructor-arg value="false"/>
                     <b:constructor-arg value="3600"/>
                     <b:constructor-arg value="900"/>
                 </b:bean>
             </b:property>
         </b:bean>
     </b:property>
 </b:bean>

  • Constructor Details

    • CasAuthenticationFilter

      public CasAuthenticationFilter()

  • Method Details

    • successfulAuthentication

      protected final void successfulAuthentication(jakarta.servlet.http.HttpServletRequest request, jakarta.servlet.http.HttpServletResponse response, jakarta.servlet.FilterChain chain, Authentication authResult) throws IOException, jakarta.servlet.ServletException
      Description copied from class: AbstractAuthenticationProcessingFilter
      Default behaviour for successful authentication.
      1. Sets the successful Authentication object on the SecurityContextHolder
      2. Informs the configured RememberMeServices of the successful login
      3. Fires an InteractiveAuthenticationSuccessEvent via the configured ApplicationEventPublisher
      4. Delegates additional behaviour to the AuthenticationSuccessHandler.
      Subclasses can override this method to continue the FilterChain after successful authentication.
      Overrides:
      successfulAuthentication in class AbstractAuthenticationProcessingFilter
      authResult - the object returned from the attemptAuthentication method.
      Throws:
      IOException
      jakarta.servlet.ServletException

    • attemptAuthentication

      public Authentication attemptAuthentication(jakarta.servlet.http.HttpServletRequest request, jakarta.servlet.http.HttpServletResponse response) throws AuthenticationException, IOException
      Description copied from class: AbstractAuthenticationProcessingFilter
      Performs actual authentication.

      The implementation should do one of the following:

      1. Return a populated authentication token for the authenticated user, indicating successful authentication
      2. Return null, indicating that the authentication process is still in progress. Before returning, the implementation should perform any additional work required to complete the process.
      3. Throw an AuthenticationException if the authentication process fails
      Specified by:
      attemptAuthentication in class AbstractAuthenticationProcessingFilter
      Parameters:
      request - from which to extract parameters and perform the authentication
      response - the response, which may be needed if the implementation has to do a redirect as part of a multi-stage authentication process (such as OIDC).
      Returns:
      the authenticated user token, or null if authentication is incomplete.
      Throws:
      AuthenticationException - if authentication fails.
      IOException

    • obtainArtifact

      protected String obtainArtifact(jakarta.servlet.http.HttpServletRequest request)
      If present, gets the artifact (CAS ticket) from the HttpServletRequest.
      Parameters:
      request -
      Returns:
      if present the artifact from the HttpServletRequest, else null

    • requiresAuthentication

      protected boolean requiresAuthentication(jakarta.servlet.http.HttpServletRequest request, jakarta.servlet.http.HttpServletResponse response)
      Overridden to provide proxying capabilities.
      Overrides:
      requiresAuthentication in class AbstractAuthenticationProcessingFilter
      Returns:
      true if the filter should attempt authentication, false otherwise.

    • setProxyAuthenticationFailureHandler

      public final void setProxyAuthenticationFailureHandler(AuthenticationFailureHandler proxyFailureHandler)
      Sets the AuthenticationFailureHandler for proxy requests.
      Parameters:
      proxyFailureHandler -

    • setAuthenticationFailureHandler

      public final void setAuthenticationFailureHandler(AuthenticationFailureHandler failureHandler)
      Wraps the AuthenticationFailureHandler to distinguish between handling proxy ticket authentication failures and service ticket failures.
      Overrides:
      setAuthenticationFailureHandler in class AbstractAuthenticationProcessingFilter

    • setProxyReceptorUrl

      public final void setProxyReceptorUrl(String proxyReceptorUrl)

    • setProxyGrantingTicketStorage

      public final void setProxyGrantingTicketStorage(org.apereo.cas.client.proxy.ProxyGrantingTicketStorage proxyGrantingTicketStorage)

    • setServiceProperties

      public final void setServiceProperties(ServiceProperties serviceProperties)