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.KerberosMessageType;
027 import org.apache.directory.server.kerberos.shared.messages.ApplicationRequest;
028 import org.apache.directory.server.kerberos.shared.messages.value.ApOptions;
029 import org.apache.directory.shared.asn1.der.ASN1InputStream;
030 import org.apache.directory.shared.asn1.der.DERApplicationSpecific;
031 import org.apache.directory.shared.asn1.der.DERBitString;
032 import org.apache.directory.shared.asn1.der.DEREncodable;
033 import org.apache.directory.shared.asn1.der.DERInteger;
034 import org.apache.directory.shared.asn1.der.DERSequence;
035 import org.apache.directory.shared.asn1.der.DERTaggedObject;
036
037
038 /**
039 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
040 * @version $Rev: 589780 $, $Date: 2007-10-29 20:14:59 +0200 (Mon, 29 Oct 2007) $
041 */
042 public class ApplicationRequestDecoder
043 {
044 /**
045 * Decodes a byte array into an {@link ApplicationRequest}.
046 *
047 * @param encodedAuthHeader
048 * @return The {@link ApplicationRequest}.
049 * @throws IOException
050 */
051 public ApplicationRequest decode( byte[] encodedAuthHeader ) throws IOException
052 {
053 ASN1InputStream ais = new ASN1InputStream( encodedAuthHeader );
054
055 DERApplicationSpecific app = ( DERApplicationSpecific ) ais.readObject();
056
057 DERSequence apreq = ( DERSequence ) app.getObject();
058
059 return decodeApplicationRequestSequence( apreq );
060 }
061
062
063 /*
064 AP-REQ ::= [APPLICATION 14] SEQUENCE {
065 pvno[0] INTEGER,
066 msg-type[1] INTEGER,
067
068 ap-options[2] APOptions,
069 ticket[3] Ticket,
070 authenticator[4] EncryptedData
071 }
072 */
073 private ApplicationRequest decodeApplicationRequestSequence( DERSequence sequence ) throws IOException
074 {
075 ApplicationRequest authHeader = new ApplicationRequest();
076
077 for ( Enumeration<DEREncodable> e = sequence.getObjects(); e.hasMoreElements(); )
078 {
079 DERTaggedObject object = ( ( DERTaggedObject ) e.nextElement() );
080 int tag = object.getTagNo();
081 DEREncodable derObject = object.getObject();
082
083 switch ( tag )
084 {
085 case 0:
086 DERInteger tag0 = ( DERInteger ) derObject;
087 authHeader.setProtocolVersionNumber( tag0.intValue() );
088 break;
089
090 case 1:
091 DERInteger tag1 = ( DERInteger ) derObject;
092 authHeader.setMessageType( KerberosMessageType.getTypeByOrdinal( tag1.intValue() ) );
093 break;
094
095 case 2:
096 DERBitString apOptions = ( DERBitString ) derObject;
097 authHeader.setApOptions( new ApOptions( apOptions.getOctets() ) );
098 break;
099 case 3:
100 DERApplicationSpecific tag3 = ( DERApplicationSpecific ) derObject;
101 authHeader.setTicket( TicketDecoder.decode( tag3 ) );
102 break;
103
104 case 4:
105 DERSequence tag4 = ( DERSequence ) derObject;
106 authHeader.setEncPart( EncryptedDataDecoder.decode( tag4 ) );
107 break;
108 }
109 }
110
111 return authHeader;
112 }
113 }