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.value.PaData;
027 import org.apache.directory.server.kerberos.shared.messages.value.types.PaDataType;
028 import org.apache.directory.shared.asn1.der.ASN1InputStream;
029 import org.apache.directory.shared.asn1.der.DEREncodable;
030 import org.apache.directory.shared.asn1.der.DERInteger;
031 import org.apache.directory.shared.asn1.der.DEROctetString;
032 import org.apache.directory.shared.asn1.der.DERSequence;
033 import org.apache.directory.shared.asn1.der.DERTaggedObject;
034
035
036 /**
037 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
038 * @version $Rev: 587624 $, $Date: 2007-10-23 22:22:08 +0300 (Tue, 23 Oct 2007) $
039 */
040 public class PreAuthenticationDataDecoder
041 {
042 /**
043 * Decodes a byte array into {@link PaData}.
044 *
045 * @param encodedPreAuthData
046 * @return The {@link PaData}.
047 * @throws IOException
048 */
049 public PaData decode( byte[] encodedPreAuthData ) throws IOException
050 {
051 ASN1InputStream ais = new ASN1InputStream( encodedPreAuthData );
052
053 DERSequence sequence = ( DERSequence ) ais.readObject();
054
055 return decode( sequence );
056 }
057
058
059 /**
060 * KDC-REQ ::= SEQUENCE {
061 * pvno[1] INTEGER,
062 * msg-type[2] INTEGER,
063 * padata[3] SEQUENCE OF PA-DATA OPTIONAL,
064 * req-body[4] KDC-REQ-BODY
065 * }
066 */
067 protected static PaData[] decodeSequence( DERSequence sequence )
068 {
069 PaData[] paDataSequence = new PaData[sequence.size()];
070
071 int ii = 0;
072
073 for ( Enumeration<DEREncodable> e = sequence.getObjects(); e.hasMoreElements(); )
074 {
075 DERSequence object = ( DERSequence ) e.nextElement();
076 PaData paData = PreAuthenticationDataDecoder.decode( object );
077 paDataSequence[ii] = paData;
078 ii++;
079 }
080
081 return paDataSequence;
082 }
083
084
085 /**
086 * PA-DATA ::= SEQUENCE {
087 * padata-type[1] INTEGER,
088 * padata-value[2] OCTET STRING,
089 * -- might be encoded AP-REQ
090 * }
091 */
092 protected static PaData decode( DERSequence sequence )
093 {
094 PaData paData = new PaData();
095
096 for ( Enumeration<DEREncodable> e = sequence.getObjects(); e.hasMoreElements(); )
097 {
098 DERTaggedObject object = ( DERTaggedObject ) e.nextElement();
099 int tag = object.getTagNo();
100 DEREncodable derObject = object.getObject();
101
102 switch ( tag )
103 {
104 case 1:
105 DERInteger padataType = ( DERInteger ) derObject;
106 PaDataType type = PaDataType.getTypeByOrdinal( padataType.intValue() );
107 paData.setPaDataType( type );
108 break;
109 case 2:
110 DEROctetString padataValue = ( DEROctetString ) derObject;
111 paData.setPaDataValue( padataValue.getOctets() );
112 break;
113 }
114 }
115
116 return paData;
117 }
118 }