1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.directory.server.kerberos.protocol;
21
22
23 import org.apache.directory.server.kerberos.shared.io.decoder.KdcRequestDecoder;
24 import org.apache.mina.common.BufferDataException;
25 import org.apache.mina.common.ByteBuffer;
26 import org.apache.mina.common.IoSession;
27 import org.apache.mina.filter.codec.CumulativeProtocolDecoder;
28 import org.apache.mina.filter.codec.ProtocolDecoderOutput;
29
30
31 /**
32 * A {@link CumulativeProtocolDecoder} which supports Kerberos operation over TCP,
33 * by reassembling split packets prior to ASN.1 DER decoding.
34 *
35 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
36 * @version $Rev$, $Date$
37 */
38 public class KerberosTcpDecoder extends CumulativeProtocolDecoder
39 {
40 private KdcRequestDecoder decoder = new KdcRequestDecoder();
41
42 private int maxObjectSize = 16384; // 16KB
43
44
45 /**
46 * Returns the allowed maximum size of the object to be decoded.
47 * If the size of the object to be decoded exceeds this value, this
48 * decoder will throw a {@link BufferDataException}. The default
49 * value is <tt>16384</tt> (16KB).
50 *
51 * @return The max object size.
52 */
53 public int getMaxObjectSize()
54 {
55 return maxObjectSize;
56 }
57
58
59 /**
60 * Sets the allowed maximum size of the object to be decoded.
61 * If the size of the object to be decoded exceeds this value, this
62 * decoder will throw a {@link BufferDataException}. The default
63 * value is <tt>16384</tt> (16KB).
64 *
65 * @param maxObjectSize
66 */
67 public void setMaxObjectSize( int maxObjectSize )
68 {
69 if ( maxObjectSize <= 0 )
70 {
71 throw new IllegalArgumentException( "maxObjectSize: " + maxObjectSize );
72 }
73
74 this.maxObjectSize = maxObjectSize;
75 }
76
77
78 @Override
79 protected boolean doDecode( IoSession session, ByteBuffer in, ProtocolDecoderOutput out ) throws Exception
80 {
81 if ( !in.prefixedDataAvailable( 4, maxObjectSize ) )
82 {
83 return false;
84 }
85
86 in.getInt();
87
88 out.write( decoder.decode( in.buf() ) );
89
90 return true;
91 }
92 }