/*

  * Copyright 2005-2007 The Kuali Foundation

  * 

  * 

  * Licensed under the Educational Community License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  * 

  * http://www.opensource.org/licenses/ecl2.php

  * 

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.kuali.rice.ksb.security.credentials;

 import java.io.IOException;

 import org.acegisecurity.context.SecurityContextHolder;

 import org.acegisecurity.providers.cas.CasAuthenticationToken;

 import org.acegisecurity.ui.cas.CasProcessingFilter;

 import org.kuali.rice.core.security.credentials.Credentials;

 import org.kuali.rice.core.security.credentials.CredentialsSource;

 import edu.yale.its.tp.cas.proxy.ProxyTicketReceptor;

 /**

  * Retrieves a proxy ticket for the user based on their provided Proxy Granting

  * Ticket. This assumes that the Proxy GrantingTicket is available from a

  * ThreadLocal and that the service is protected by Acegi.

  * <p>

  * Note: this class can be used for user-to-service authentication.

  * <p>

  * This assumes the services are stateless and will not maintain an HttpSession

  * so each call for credentials will result in a new Proxy Ticket being granted.

  * 

  * @author Kuali Rice Team (rice.collab@kuali.org)

  * @since 0.9

  * @see ThreadLocal

  * @see ProxyTicketReceptor

  */

 public final class CasProxyTicketCredentialsSource implements CredentialsSource {

     public Credentials getCredentials(final String serviceEndpoint) {

             final String proxyGrantingTicketIou = ((CasAuthenticationToken) (SecurityContextHolder

                 .getContext()).getAuthentication()).getProxyGrantingTicketIou();

             try {

                 final String proxyTicket = ProxyTicketReceptor.getProxyTicket(

                     proxyGrantingTicketIou, serviceEndpoint);

                 return new UsernamePasswordCredentials(

                         CasProcessingFilter.CAS_STATELESS_IDENTIFIER, proxyTicket);

                 } catch (final IOException e) {

                     return null;

                 }

         }

     public CredentialsType getSupportedCredentialsType() {

         return CredentialsType.CAS;

     }

 }