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.value.AuthorizationData;
028 import org.apache.directory.server.kerberos.shared.messages.value.AuthorizationDataEntry;
029 import org.apache.directory.server.kerberos.shared.messages.value.types.AuthorizationType;
030 import org.apache.directory.shared.asn1.der.ASN1InputStream;
031 import org.apache.directory.shared.asn1.der.DEREncodable;
032 import org.apache.directory.shared.asn1.der.DERInteger;
033 import org.apache.directory.shared.asn1.der.DEROctetString;
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: 587531 $, $Date: 2007-10-23 17:59:10 +0300 (Tue, 23 Oct 2007) $
041 */
042 public class AuthorizationDataDecoder implements Decoder, DecoderFactory
043 {
044 public Decoder getDecoder()
045 {
046 return new AuthorizationDataDecoder();
047 }
048
049
050 public Encodable decode( byte[] encodedAuthData ) throws IOException
051 {
052 ASN1InputStream ais = new ASN1InputStream( encodedAuthData );
053
054 DERSequence sequence = ( DERSequence ) ais.readObject();
055
056 return decodeSequence( sequence );
057 }
058
059
060 /**
061 * AuthorizationData ::= SEQUENCE OF SEQUENCE {
062 * ad-type[0] INTEGER,
063 * ad-data[1] OCTET STRING
064 * }
065 */
066 protected static AuthorizationData decodeSequence( DERSequence sequence )
067 {
068 AuthorizationData authData = new AuthorizationData();
069
070 for ( Enumeration<DEREncodable> e = sequence.getObjects(); e.hasMoreElements(); )
071 {
072 DERSequence object = ( DERSequence ) e.nextElement();
073 AuthorizationDataEntry entry = decodeAuthorizationEntry( object );
074 authData.add( entry );
075 }
076
077 return authData;
078 }
079
080
081 protected static AuthorizationDataEntry decodeAuthorizationEntry( DERSequence sequence )
082 {
083 AuthorizationType type = AuthorizationType.NULL;
084 byte[] data = null;
085
086 for ( Enumeration<DEREncodable> e = sequence.getObjects(); e.hasMoreElements(); )
087 {
088 DERTaggedObject object = ( DERTaggedObject ) e.nextElement();
089 int tag = object.getTagNo();
090 DEREncodable derObject = object.getObject();
091
092 switch ( tag )
093 {
094 case 0:
095 DERInteger tag0 = ( DERInteger ) derObject;
096 type = AuthorizationType.getTypeByOrdinal( tag0.intValue() );
097 break;
098
099 case 1:
100 DEROctetString tag1 = ( DEROctetString ) derObject;
101 data = tag1.getOctets();
102 break;
103 }
104 }
105
106 return new AuthorizationDataEntry( type, data );
107 }
108 }