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.Encodable; 027 import org.apache.directory.server.kerberos.shared.messages.components.EncApRepPart; 028 import org.apache.directory.server.kerberos.shared.messages.components.EncApRepPartModifier; 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.DEREncodable; 032 import org.apache.directory.shared.asn1.der.DERGeneralizedTime; 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: 502338 $, $Date: 2007-02-01 11:59:43 -0800 (Thu, 01 Feb 2007) $ 041 */ 042 public class EncApRepPartDecoder implements Decoder, DecoderFactory 043 { 044 public Decoder getDecoder() 045 { 046 return new EncApRepPartDecoder(); 047 } 048 049 050 public Encodable decode( byte[] encodedEncApRepPart ) throws IOException 051 { 052 ASN1InputStream ais = new ASN1InputStream( encodedEncApRepPart ); 053 054 DERApplicationSpecific app = ( DERApplicationSpecific ) ais.readObject(); 055 056 DERSequence apRepPart = ( DERSequence ) app.getObject(); 057 058 return decodeEncApRepPartSequence( apRepPart ); 059 } 060 061 062 /** 063 * Decodes a {@link DERSequence} into a {@link EncApRepPart}. 064 * 065 * EncAPRepPart ::= [APPLICATION 27] SEQUENCE { 066 * ctime [0] KerberosTime, 067 * cusec [1] Microseconds, 068 * subkey [2] EncryptionKey OPTIONAL, 069 * seq-number [3] UInt32 OPTIONAL 070 * } 071 * 072 * @param sequence 073 * @return The {@link EncApRepPart}. 074 */ 075 private EncApRepPart decodeEncApRepPartSequence( DERSequence sequence ) 076 { 077 EncApRepPartModifier modifier = new EncApRepPartModifier(); 078 079 for ( Enumeration e = sequence.getObjects(); e.hasMoreElements(); ) 080 { 081 DERTaggedObject object = ( DERTaggedObject ) e.nextElement(); 082 int tag = object.getTagNo(); 083 DEREncodable derObject = object.getObject(); 084 085 switch ( tag ) 086 { 087 case 0: 088 DERGeneralizedTime tag0 = ( DERGeneralizedTime ) derObject; 089 modifier.setClientTime( KerberosTimeDecoder.decode( tag0 ) ); 090 break; 091 case 1: 092 DERInteger tag1 = ( DERInteger ) derObject; 093 modifier.setClientMicroSecond( new Integer( tag1.intValue() ) ); 094 break; 095 case 2: 096 DERSequence tag2 = ( DERSequence ) derObject; 097 modifier.setSubSessionKey( EncryptionKeyDecoder.decode( tag2 ) ); 098 break; 099 case 3: 100 DERInteger tag3 = ( DERInteger ) derObject; 101 modifier.setSequenceNumber( new Integer( tag3.intValue() ) ); 102 break; 103 } 104 } 105 106 return modifier.getEncApRepPart(); 107 } 108 }