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.EncryptedData;
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: 587682 $, $Date: 2007-10-24 00:47:43 +0200 (Wed, 24 Oct 2007) $
037     */
038    public class EncryptedDataEncoder
039    {
040        /**
041         * Encodes an {@link EncryptedData} into a byte array.
042         *
043         * @param encryptedData
044         * @return The byte array.
045         * @throws IOException
046         */
047        public static byte[] encode( EncryptedData encryptedData ) throws IOException
048        {
049            ByteArrayOutputStream baos = new ByteArrayOutputStream();
050            ASN1OutputStream aos = new ASN1OutputStream( baos );
051    
052            aos.writeObject( encodeSequence( encryptedData ) );
053            aos.close();
054    
055            return baos.toByteArray();
056        }
057    
058    
059        /**
060         * Encodes an {@link EncryptedData} into a {@link DERSequence}.
061         * 
062         * EncryptedData ::=   SEQUENCE {
063         *             etype[0]     INTEGER, -- EncryptionEngine
064         *             kvno[1]      INTEGER OPTIONAL,
065         *             cipher[2]    OCTET STRING -- ciphertext
066         * }
067         * 
068         * @param encryptedData 
069         * @return The {@link DERSequence}.
070         */
071        public static DERSequence encodeSequence( EncryptedData encryptedData )
072        {
073            DERSequence sequence = new DERSequence();
074    
075            sequence.add( new DERTaggedObject( 0, DERInteger.valueOf( encryptedData.getEType().getOrdinal() ) ) );
076    
077            if ( encryptedData.hasKvno() )
078            {
079                sequence.add( new DERTaggedObject( 1, DERInteger.valueOf( encryptedData.getKvno() ) ) );
080            }
081    
082            sequence.add( new DERTaggedObject( 2, new DEROctetString( encryptedData.getCipher() ) ) );
083    
084            return sequence;
085        }
086    }