1/**
2 * $RCSfile$
3 * $Revision$
4 * $Date$
5 *
6 * Copyright 2003-2006 Jive Software.
7 *
8 * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License");
9 * you may not use this file except in compliance with the License.
10 * You may obtain a copy of the License at
11 *
12 *     http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing, software
15 * distributed under the License is distributed on an "AS IS" BASIS,
16 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 * See the License for the specific language governing permissions and
18 * limitations under the License.
19 */
20package org.jivesoftware.smackx.filetransfer;
21
22import java.io.InputStream;
23import java.io.OutputStream;
24
25import org.jivesoftware.smack.Connection;
26import org.jivesoftware.smack.XMPPException;
27import org.jivesoftware.smack.filter.AndFilter;
28import org.jivesoftware.smack.filter.FromContainsFilter;
29import org.jivesoftware.smack.filter.PacketFilter;
30import org.jivesoftware.smack.filter.PacketTypeFilter;
31import org.jivesoftware.smack.packet.IQ;
32import org.jivesoftware.smack.packet.Packet;
33import org.jivesoftware.smackx.bytestreams.ibb.InBandBytestreamManager;
34import org.jivesoftware.smackx.bytestreams.ibb.InBandBytestreamRequest;
35import org.jivesoftware.smackx.bytestreams.ibb.InBandBytestreamSession;
36import org.jivesoftware.smackx.bytestreams.ibb.packet.Open;
37import org.jivesoftware.smackx.packet.StreamInitiation;
38
39/**
40 * The In-Band Bytestream file transfer method, or IBB for short, transfers the
41 * file over the same XML Stream used by XMPP. It is the fall-back mechanism in
42 * case the SOCKS5 bytestream method of transferring files is not available.
43 *
44 * @author Alexander Wenckus
45 * @author Henning Staib
46 * @see <a href="http://xmpp.org/extensions/xep-0047.html">XEP-0047: In-Band
47 *      Bytestreams (IBB)</a>
48 */
49public class IBBTransferNegotiator extends StreamNegotiator {
50
51    private Connection connection;
52
53    private InBandBytestreamManager manager;
54
55    /**
56     * The default constructor for the In-Band Bytestream Negotiator.
57     *
58     * @param connection The connection which this negotiator works on.
59     */
60    protected IBBTransferNegotiator(Connection connection) {
61        this.connection = connection;
62        this.manager = InBandBytestreamManager.getByteStreamManager(connection);
63    }
64
65    public OutputStream createOutgoingStream(String streamID, String initiator,
66                    String target) throws XMPPException {
67        InBandBytestreamSession session = this.manager.establishSession(target, streamID);
68        session.setCloseBothStreamsEnabled(true);
69        return session.getOutputStream();
70    }
71
72    public InputStream createIncomingStream(StreamInitiation initiation)
73                    throws XMPPException {
74        /*
75         * In-Band Bytestream initiation listener must ignore next in-band
76         * bytestream request with given session ID
77         */
78        this.manager.ignoreBytestreamRequestOnce(initiation.getSessionID());
79
80        Packet streamInitiation = initiateIncomingStream(this.connection, initiation);
81        return negotiateIncomingStream(streamInitiation);
82    }
83
84    public PacketFilter getInitiationPacketFilter(String from, String streamID) {
85        /*
86         * this method is always called prior to #negotiateIncomingStream() so
87         * the In-Band Bytestream initiation listener must ignore the next
88         * In-Band Bytestream request with the given session ID
89         */
90        this.manager.ignoreBytestreamRequestOnce(streamID);
91
92        return new AndFilter(new FromContainsFilter(from), new IBBOpenSidFilter(streamID));
93    }
94
95    public String[] getNamespaces() {
96        return new String[] { InBandBytestreamManager.NAMESPACE };
97    }
98
99    InputStream negotiateIncomingStream(Packet streamInitiation) throws XMPPException {
100        // build In-Band Bytestream request
101        InBandBytestreamRequest request = new ByteStreamRequest(this.manager,
102                        (Open) streamInitiation);
103
104        // always accept the request
105        InBandBytestreamSession session = request.accept();
106        session.setCloseBothStreamsEnabled(true);
107        return session.getInputStream();
108    }
109
110    public void cleanup() {
111    }
112
113    /**
114     * This PacketFilter accepts an incoming In-Band Bytestream open request
115     * with a specified session ID.
116     */
117    private static class IBBOpenSidFilter extends PacketTypeFilter {
118
119        private String sessionID;
120
121        public IBBOpenSidFilter(String sessionID) {
122            super(Open.class);
123            if (sessionID == null) {
124                throw new IllegalArgumentException("StreamID cannot be null");
125            }
126            this.sessionID = sessionID;
127        }
128
129        public boolean accept(Packet packet) {
130            if (super.accept(packet)) {
131                Open bytestream = (Open) packet;
132
133                // packet must by of type SET and contains the given session ID
134                return this.sessionID.equals(bytestream.getSessionID())
135                                && IQ.Type.SET.equals(bytestream.getType());
136            }
137            return false;
138        }
139    }
140
141    /**
142     * Derive from InBandBytestreamRequest to access protected constructor.
143     */
144    private static class ByteStreamRequest extends InBandBytestreamRequest {
145
146        private ByteStreamRequest(InBandBytestreamManager manager, Open byteStreamRequest) {
147            super(manager, byteStreamRequest);
148        }
149
150    }
151
152}
153