001    /**
002     *
003     * Copyright 2005 The Apache Software Foundation
004     *
005     *  Licensed under the Apache License, Version 2.0 (the "License");
006     *  you may not use this file except in compliance with the License.
007     *  You may obtain a copy of the License at
008     *
009     *     http://www.apache.org/licenses/LICENSE-2.0
010     *
011     *  Unless required by applicable law or agreed to in writing, software
012     *  distributed under the License is distributed on an "AS IS" BASIS,
013     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     *  See the License for the specific language governing permissions and
015     *  limitations under the License.
016     */
017    package org.apache.geronimo.tomcat.valve;
018    
019    import java.io.IOException;
020    
021    import javax.servlet.ServletException;
022    import javax.security.auth.Subject;
023    
024    import org.apache.catalina.valves.ValveBase;
025    import org.apache.catalina.connector.Request;
026    import org.apache.catalina.connector.Response;
027    import org.apache.geronimo.security.ContextManager;
028    import org.apache.geronimo.security.Callers;
029    
030    /**
031     * @version $Rev: 431706 $ $Date: 2006-08-15 14:19:27 -0700 (Tue, 15 Aug 2006) $
032     */
033    public class DefaultSubjectValve extends ValveBase {
034    
035        private final Subject defaultSubject;
036    
037        public DefaultSubjectValve(Subject defaultSubject) {
038            this.defaultSubject = defaultSubject;
039        }
040    
041        public void invoke(Request request, Response response) throws IOException, ServletException {
042            Callers oldCallers = null;
043            boolean setSubject = false;
044            if (defaultSubject != null) {
045                oldCallers = ContextManager.getCallers();
046                setSubject = oldCallers == null || oldCallers.getCurrentCaller() == null;
047            }
048            if (setSubject) {
049                ContextManager.setCallers(defaultSubject, defaultSubject);
050                try {
051                    getNext().invoke(request, response);
052                } finally {
053                    ContextManager.popCallers(oldCallers);
054                }
055            } else {
056                getNext().invoke(request, response);
057            }
058    
059        }
060    }