1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.directory.shared.kerberos.messages;
21
22
23 import java.nio.ByteBuffer;
24
25 import org.apache.directory.api.asn1.EncoderException;
26 import org.apache.directory.api.asn1.ber.tlv.TLV;
27 import org.apache.directory.shared.kerberos.KerberosConstants;
28 import org.apache.directory.shared.kerberos.KerberosMessageType;
29 import org.apache.directory.shared.kerberos.components.KdcReq;
30
31
32 /**
33 * TGS-REQ message. It's just a KDC-REQ message with a message type set to 12.
34 * It will store the object described by the ASN.1 grammar :
35 * <pre>
36 * TGS-REQ ::= [APPLICATION 12] <KDC-REQ>
37 * </pre>
38 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
39 */
40 public class TgsReq extends KdcReq
41 {
42 // Storage for computed lengths
43 private int kdcReqLength;
44 private int tgsReqLength;
45
46
47 /**
48 * Creates a new instance of TGS-REQ.
49 */
50 public TgsReq()
51 {
52 super( KerberosMessageType.TGS_REQ );
53 }
54
55
56 /**
57 * Compute the TGS-REQ length
58 * <pre>
59 * TGS-REQ :
60 *
61 * 0x6A L1 TGS-REQ message
62 * |
63 * +--> 0x30 L2 KDC-REQ sequence
64 * </pre>
65 */
66 @Override
67 public int computeLength()
68 {
69 kdcReqLength = 0;
70 tgsReqLength = 0;
71
72 kdcReqLength = super.computeLength();
73 tgsReqLength = 1 + TLV.getNbBytes( kdcReqLength ) + kdcReqLength;
74
75 return tgsReqLength;
76 }
77
78
79 /**
80 * Encode the TGS-REQ component
81 *
82 * @param buffer The buffer containing the encoded result
83 * @return The encoded component
84 * @throws EncoderException If the encoding failed
85 */
86 @Override
87 public ByteBuffer encode( ByteBuffer buffer ) throws EncoderException
88 {
89 if ( buffer == null )
90 {
91 buffer = ByteBuffer.allocate( computeLength() );
92 }
93
94 // The TGS-REQ SEQ Tag
95 buffer.put( ( byte ) KerberosConstants.TGS_REQ_TAG );
96 buffer.put( TLV.getBytes( kdcReqLength ) );
97
98 // The KDC-REQ --------------------------------------------------------
99 super.encode( buffer );
100
101 return buffer;
102 }
103 }