001    /****************************************************************
002     * Licensed to the Apache Software Foundation (ASF) under one   *
003     * or more contributor license agreements.  See the NOTICE file *
004     * distributed with this work for additional information        *
005     * regarding copyright ownership.  The ASF licenses this file   *
006     * to you under the Apache License, Version 2.0 (the            *
007     * "License"); you may not use this file except in compliance   *
008     * with the License.  You may obtain a copy of the License at   *
009     *                                                              *
010     *   http://www.apache.org/licenses/LICENSE-2.0                 *
011     *                                                              *
012     * Unless required by applicable law or agreed to in writing,   *
013     * software distributed under the License is distributed on an  *
014     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
015     * KIND, either express or implied.  See the License for the    *
016     * specific language governing permissions and limitations      *
017     * under the License.                                           *
018     ****************************************************************/
019    
020    package org.apache.james.protocols.smtp.core.fastfail;
021    
022    import org.apache.james.protocols.smtp.SMTPSession;
023    
024    
025    import java.net.UnknownHostException;
026    
027    
028    public class ReverseEqualsEhloHeloHandler extends ResolvableEhloHeloHandler {
029    
030        /**
031         * @see org.apache.james.protocols.smtp.core.fastfail.ResolvableEhloHeloHandler#isBadHelo(org.apache.james.protocols.smtp.SMTPSession, java.lang.String)
032         */
033        protected boolean isBadHelo(SMTPSession session, String argument) {
034            try {
035                // get reverse entry
036                String reverse = dnsService.getHostName(dnsService.getByName(
037                        session.getRemoteIPAddress()));
038                if (!argument.equals(reverse)) {
039                    return true;
040                }
041            } catch (UnknownHostException e) {
042                return true;
043            }
044            return false;
045        }
046        
047    }