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.crypto.encryption.EncryptionType;
027 import org.apache.directory.server.kerberos.shared.messages.value.EncryptionTypeInfo2Entry;
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.DERGeneralString;
031 import org.apache.directory.shared.asn1.der.DERInteger;
032 import org.apache.directory.shared.asn1.der.DEROctetString;
033 import org.apache.directory.shared.asn1.der.DERSequence;
034 import org.apache.directory.shared.asn1.der.DERTaggedObject;
035
036
037 /**
038 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
039 * @version $Rev: 540371 $, $Date: 2007-05-21 17:00:43 -0700 (Mon, 21 May 2007) $
040 */
041 public class EncryptionTypeInfo2Decoder
042 {
043 /**
044 * Decodes a byte array into an array of {@link EncryptionTypeInfo2Entry}.
045 *
046 * @param encodedEntries
047 * @return The array of {@link EncryptionTypeInfo2Entry}.
048 * @throws IOException
049 */
050 public EncryptionTypeInfo2Entry[] decode( byte[] encodedEntries ) throws IOException
051 {
052 ASN1InputStream ais = new ASN1InputStream( encodedEntries );
053
054 DERSequence sequence = ( DERSequence ) ais.readObject();
055
056 return decodeSequence( sequence );
057 }
058
059
060 /**
061 * ETYPE-INFO2 ::= SEQUENCE SIZE (1..MAX) OF ETYPE-INFO2-ENTRY
062 */
063 protected static EncryptionTypeInfo2Entry[] decodeSequence( DERSequence sequence )
064 {
065 EncryptionTypeInfo2Entry[] entrySequence = new EncryptionTypeInfo2Entry[sequence.size()];
066
067 int ii = 0;
068 for ( Enumeration<DEREncodable> e = sequence.getObjects(); e.hasMoreElements(); )
069 {
070 DERSequence object = (DERSequence)e.nextElement();
071 entrySequence[ii] = decode( object );
072 ii++;
073 }
074
075 return entrySequence;
076 }
077
078
079 /**
080 * ETYPE-INFO2-ENTRY ::= SEQUENCE {
081 * etype [0] Int32,
082 * salt [1] KerberosString OPTIONAL,
083 * s2kparams [2] OCTET STRING OPTIONAL
084 * }
085 */
086 protected static EncryptionTypeInfo2Entry decode( DERSequence sequence )
087 {
088 EncryptionType encryptionType = EncryptionType.NULL;
089 String salt = new String();
090 byte[] s2kparams = new byte[0];
091
092 for ( Enumeration<DEREncodable> e = sequence.getObjects(); e.hasMoreElements(); )
093 {
094 DERTaggedObject object = (DERTaggedObject)e.nextElement();
095 int tag = object.getTagNo();
096 DEREncodable derObject = object.getObject();
097
098 switch ( tag )
099 {
100 case 0:
101 DERInteger tag0 = ( DERInteger ) derObject;
102 encryptionType = EncryptionType.getTypeByOrdinal( tag0.intValue() );
103 break;
104 case 1:
105 DERGeneralString tag1 = ( DERGeneralString ) derObject;
106 salt = tag1.getString();
107 break;
108 case 2:
109 DEROctetString tag2 = ( DEROctetString ) derObject;
110 s2kparams = tag2.getOctets();
111 break;
112 }
113 }
114
115 return new EncryptionTypeInfo2Entry( encryptionType, salt, s2kparams );
116 }
117 }