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.PaData;
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: 587624 $, $Date: 2007-10-23 21:22:08 +0200 (Tue, 23 Oct 2007) $
037     */
038    public class PreAuthenticationDataEncoder
039    {
040        /**
041         * Encodes an array of {@link PaData}s into a byte array.
042         *
043         * @param preAuth
044         * @return The byte array.
045         * @throws IOException
046         */
047        public static byte[] encode( PaData[] preAuth ) throws IOException
048        {
049            ByteArrayOutputStream baos = new ByteArrayOutputStream();
050            ASN1OutputStream aos = new ASN1OutputStream( baos );
051    
052            aos.writeObject( encodeSequence( preAuth ) );
053            aos.close();
054    
055            return baos.toByteArray();
056        }
057    
058    
059        /**
060         * METHOD-DATA     ::= SEQUENCE OF PA-DATA
061         */
062        protected static DERSequence encodeSequence( PaData[] preAuth )
063        {
064            DERSequence sequence = new DERSequence();
065    
066            for ( int ii = 0; ii < preAuth.length; ii++ )
067            {
068                sequence.add( encode( preAuth[ii] ) );
069            }
070    
071            return sequence;
072        }
073    
074    
075        /**
076         * PA-DATA ::=        SEQUENCE {
077         *         padata-type[1]        INTEGER,
078         *         padata-value[2]       OCTET STRING
079         * }
080         */
081        protected static DERSequence encode( PaData preAuth )
082        {
083            DERSequence sequence = new DERSequence();
084    
085            sequence.add( new DERTaggedObject( 1, DERInteger.valueOf( preAuth.getPaDataType().getOrdinal() ) ) );
086    
087            if ( preAuth.getPaDataValue() != null )
088            {
089                sequence.add( new DERTaggedObject( 2, new DEROctetString( preAuth.getPaDataValue() ) ) );
090            }
091    
092            return sequence;
093        }
094    }