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 */ 020package org.apache.directory.shared.kerberos.messages; 021 022 023import java.nio.ByteBuffer; 024 025import org.apache.directory.api.asn1.EncoderException; 026import org.apache.directory.api.asn1.ber.tlv.TLV; 027import org.apache.directory.shared.kerberos.KerberosConstants; 028import org.apache.directory.shared.kerberos.KerberosMessageType; 029import org.apache.directory.shared.kerberos.components.KdcReq; 030 031 032/** 033 * TGS-REQ message. It's just a KDC-REQ message with a message type set to 12. 034 * It will store the object described by the ASN.1 grammar : 035 * <pre> 036 * TGS-REQ ::= [APPLICATION 12] <KDC-REQ> 037 * </pre> 038 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 039 */ 040public class TgsReq extends KdcReq 041{ 042 // Storage for computed lengths 043 private int kdcReqLength; 044 private int tgsReqLength; 045 046 047 /** 048 * Creates a new instance of TGS-REQ. 049 */ 050 public TgsReq() 051 { 052 super( KerberosMessageType.TGS_REQ ); 053 } 054 055 056 /** 057 * Compute the TGS-REQ length 058 * <pre> 059 * TGS-REQ : 060 * 061 * 0x6A L1 TGS-REQ message 062 * | 063 * +--> 0x30 L2 KDC-REQ sequence 064 * </pre> 065 */ 066 @Override 067 public int computeLength() 068 { 069 kdcReqLength = 0; 070 tgsReqLength = 0; 071 072 kdcReqLength = super.computeLength(); 073 tgsReqLength = 1 + TLV.getNbBytes( kdcReqLength ) + kdcReqLength; 074 075 return tgsReqLength; 076 } 077 078 079 /** 080 * Encode the TGS-REQ component 081 * 082 * @param buffer The buffer containing the encoded result 083 * @return The encoded component 084 * @throws EncoderException If the encoding failed 085 */ 086 @Override 087 public ByteBuffer encode( ByteBuffer buffer ) throws EncoderException 088 { 089 if ( buffer == null ) 090 { 091 buffer = ByteBuffer.allocate( computeLength() ); 092 } 093 094 // The TGS-REQ SEQ Tag 095 buffer.put( ( byte ) KerberosConstants.TGS_REQ_TAG ); 096 buffer.put( TLV.getBytes( kdcReqLength ) ); 097 098 // The KDC-REQ -------------------------------------------------------- 099 super.encode( buffer ); 100 101 return buffer; 102 } 103}