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 */
020package org.apache.directory.server.kerberos.changepwd.messages;
021
022
023import java.nio.ByteBuffer;
024
025import org.apache.directory.api.asn1.EncoderException;
026import org.apache.directory.server.kerberos.changepwd.exceptions.ChangePasswdErrorType;
027import org.apache.directory.server.kerberos.changepwd.exceptions.ChangePasswordException;
028import org.apache.directory.shared.kerberos.codec.KerberosDecoder;
029import org.apache.directory.shared.kerberos.exceptions.KerberosException;
030import org.apache.directory.shared.kerberos.messages.ApReq;
031import org.apache.directory.shared.kerberos.messages.KrbPriv;
032
033
034/**
035 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
036 */
037public class ChangePasswordRequest extends AbstractPasswordMessage
038{
039    private ApReq authHeader;
040    private KrbPriv privateMessage;
041
042    private short authHeaderLen;
043    private short privateMessageLen;
044    private short messageLength;
045
046
047    public ChangePasswordRequest( ApReq authHeader, KrbPriv privateMessage )
048    {
049        this( PVNO, authHeader, privateMessage );
050    }
051
052
053    /**
054     * Creates a new instance of ChangePasswordRequest.
055     *
056     * @param versionNumber The version number
057     * @param authHeader The authentication header
058     * @param privateMessage The private part
059     */
060    public ChangePasswordRequest( short versionNumber, ApReq authHeader, KrbPriv privateMessage )
061    {
062        super( versionNumber );
063
064        this.authHeader = authHeader;
065        this.privateMessage = privateMessage;
066    }
067
068
069    /**
070     * Returns the {@link ApReq}.
071     *
072     * @return The {@link ApReq}.
073     */
074    public ApReq getAuthHeader()
075    {
076        return authHeader;
077    }
078
079
080    /**
081     * Returns the {@link KrbPriv}.
082     *
083     * @return The {@link KrbPriv}.
084     */
085    public KrbPriv getPrivateMessage()
086    {
087        return privateMessage;
088    }
089
090
091    @Override
092    public short computeLength()
093    {
094        authHeaderLen = ( short ) authHeader.computeLength();
095        privateMessageLen = ( short ) privateMessage.computeLength();
096
097        messageLength = ( short ) ( HEADER_LENGTH + authHeaderLen + privateMessageLen );
098
099        return messageLength;
100    }
101
102
103    @Override
104    public ByteBuffer encode( ByteBuffer buf ) throws EncoderException
105    {
106        buf.putShort( messageLength );
107        buf.putShort( getVersionNumber() );
108
109        // Build application request bytes
110        buf.putShort( authHeaderLen );
111        authHeader.encode( buf );
112
113        privateMessage.encode( buf );
114
115        return buf;
116    }
117
118
119    /**
120     * Decodes a {@link ByteBuffer} into a {@link ChangePasswordRequest}.
121     *
122     * @param buf
123     * @return The {@link ChangePasswordRequest}.
124     * @throws ChangePasswordException If the decoding failed
125     */
126    public static ChangePasswordRequest decode( ByteBuffer buf ) throws ChangePasswordException
127    {
128        try
129        {
130            buf.getShort(); // message length
131
132            short pvno = buf.getShort();
133
134            short authHeaderLength = buf.getShort();
135
136            byte[] undecodedAuthHeader = new byte[authHeaderLength];
137            buf.get( undecodedAuthHeader, 0, authHeaderLength );
138
139            ApReq authHeader = KerberosDecoder.decodeApReq( undecodedAuthHeader );
140
141            byte[] encodedPrivate = new byte[buf.remaining()];
142            buf.get( encodedPrivate, 0, buf.remaining() );
143
144            KrbPriv privMessage = KerberosDecoder.decodeKrbPriv( encodedPrivate );
145
146            return new ChangePasswordRequest( pvno, authHeader, privMessage );
147        }
148        catch ( KerberosException e )
149        {
150            throw new ChangePasswordException( ChangePasswdErrorType.KRB5_KPASSWD_MALFORMED, e );
151        }
152    }
153
154}