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.directory.server.kerberos.shared.io.decoder;
021
022
023 import java.io.IOException;
024 import java.util.Enumeration;
025
026 import org.apache.directory.server.kerberos.shared.messages.application.ApplicationReply;
027 import org.apache.directory.shared.asn1.der.ASN1InputStream;
028 import org.apache.directory.shared.asn1.der.DERApplicationSpecific;
029 import org.apache.directory.shared.asn1.der.DEREncodable;
030 import org.apache.directory.shared.asn1.der.DERSequence;
031 import org.apache.directory.shared.asn1.der.DERTaggedObject;
032
033
034 /**
035 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
036 * @version $Rev: 540371 $, $Date: 2007-05-21 17:00:43 -0700 (Mon, 21 May 2007) $
037 */
038 public class ApplicationReplyDecoder
039 {
040 /**
041 * Decodes a byte array into an {@link ApplicationReply}.
042 *
043 * @param encodedAuthHeader
044 * @return The {@link ApplicationReply}.
045 * @throws IOException
046 */
047 public ApplicationReply decode( byte[] encodedAuthHeader ) throws IOException
048 {
049 ASN1InputStream ais = new ASN1InputStream( encodedAuthHeader );
050
051 DERApplicationSpecific app = ( DERApplicationSpecific ) ais.readObject();
052
053 DERSequence apreq = ( DERSequence ) app.getObject();
054
055 return decodeApplicationRequestSequence( apreq );
056 }
057
058
059 /*
060 AP-REP ::= [APPLICATION 15] SEQUENCE {
061 pvno[0] INTEGER,
062 msg-type[1] INTEGER,
063 enc-part[2] EncryptedData
064 }
065 */
066 private ApplicationReply decodeApplicationRequestSequence( DERSequence sequence )
067 {
068 ApplicationReply authHeader = null;
069
070 for ( Enumeration e = sequence.getObjects(); e.hasMoreElements(); )
071 {
072 DERTaggedObject object = ( ( DERTaggedObject ) e.nextElement() );
073 int tag = object.getTagNo();
074 DEREncodable derObject = object.getObject();
075
076 switch ( tag )
077 {
078 case 0:
079 //DERInteger tag0 = ( DERInteger ) derObject;
080 //authHeader.setProtocolVersionNumber( tag0.intValue() );
081 break;
082 case 1:
083 //DERInteger tag1 = ( DERInteger ) derObject;
084 //authHeader.setMessageType( MessageType.getTypeByOrdinal( tag1.intValue() ) );
085 break;
086 case 2:
087 DERSequence tag2 = ( DERSequence ) derObject;
088 authHeader = new ApplicationReply( EncryptedDataDecoder.decode( tag2 ) );
089 break;
090 }
091 }
092
093 return authHeader;
094 }
095 }