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.encoder;
021    
022    
023    import java.io.ByteArrayOutputStream;
024    import java.io.IOException;
025    
026    import org.apache.directory.server.kerberos.shared.messages.value.EncryptionTypeInfoEntry;
027    import org.apache.directory.shared.asn1.der.ASN1OutputStream;
028    import org.apache.directory.shared.asn1.der.DERInteger;
029    import org.apache.directory.shared.asn1.der.DEROctetString;
030    import org.apache.directory.shared.asn1.der.DERSequence;
031    import org.apache.directory.shared.asn1.der.DERTaggedObject;
032    
033    
034    /**
035     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
036     * @version $Rev: 540371 $, $Date: 2007-05-22 02:00:43 +0200 (Tue, 22 May 2007) $
037     */
038    public class EncryptionTypeInfoEncoder
039    {
040        /**
041         * Encodes an array of {@link EncryptionTypeInfoEntry}s into a byte array.
042         *
043         * @param entries
044         * @return The byte array.
045         * @throws IOException
046         */
047        public static byte[] encode( EncryptionTypeInfoEntry[] entries ) throws IOException
048        {
049            ByteArrayOutputStream baos = new ByteArrayOutputStream();
050            ASN1OutputStream aos = new ASN1OutputStream( baos );
051            aos.writeObject( encodeSequence( entries ) );
052            aos.close();
053    
054            return baos.toByteArray();
055        }
056    
057    
058        /**
059         * ETYPE-INFO              ::= SEQUENCE OF ETYPE-INFO-ENTRY
060         */
061        protected static DERSequence encodeSequence( EncryptionTypeInfoEntry[] entries )
062        {
063            DERSequence sequence = new DERSequence();
064    
065            for ( int ii = 0; ii < entries.length; ii++ )
066            {
067                sequence.add( encode( entries[ii] ) );
068            }
069    
070            return sequence;
071        }
072    
073    
074        /**
075         * ETYPE-INFO-ENTRY        ::= SEQUENCE {
076         *     etype               [0] Int32,
077         *     salt                [1] OCTET STRING OPTIONAL
078         * }
079         */
080        protected static DERSequence encode( EncryptionTypeInfoEntry entry )
081        {
082            DERSequence sequence = new DERSequence();
083    
084            sequence.add( new DERTaggedObject( 0, DERInteger.valueOf( entry.getEncryptionType().getOrdinal() ) ) );
085    
086            if ( entry.getSalt() != null )
087            {
088                sequence.add( new DERTaggedObject( 1, new DEROctetString( entry.getSalt() ) ) );
089            }
090    
091            return sequence;
092        }
093    }