socketreader.java

基于Jabber协议的即时消息服务器

/**
 * $RCSfile$
 * $Revision: 3187 $
 * $Date: 2005-12-11 13:34:34 -0300 (Sun, 11 Dec 2005) $
 *
 * Copyright (C) 2004 Jive Software. All rights reserved.
 *
 * This software is published under the terms of the GNU Public License (GPL),
 * a copy of which is included in this distribution.
 */

package org.jivesoftware.wildfire.net;

import org.dom4j.Element;
import org.dom4j.io.XMPPPacketReader;
import org.jivesoftware.util.LocaleUtils;
import org.jivesoftware.util.Log;
import org.jivesoftware.util.StringUtils;
import org.jivesoftware.wildfire.*;
import org.jivesoftware.wildfire.auth.UnauthorizedException;
import org.jivesoftware.wildfire.interceptor.InterceptorManager;
import org.jivesoftware.wildfire.interceptor.PacketRejectedException;
import org.jivesoftware.wildfire.server.OutgoingSessionPromise;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;
import org.xmpp.packet.*;

import java.io.IOException;
import java.net.Socket;

/**
 * A SocketReader creates the appropriate {@link Session} based on the defined namespace in the
 * stream element and will then keep reading and routing the received packets.
 *
 * @author Gaston Dombiak
 */
public abstract class SocketReader implements Runnable {

    /**
     * The utf-8 charset for decoding and encoding Jabber packet streams.
     */
    private static String CHARSET = "UTF-8";
    /**
     * Reuse the same factory for all the connections.
     */
    private static XmlPullParserFactory factory = null;

    /**
     * Session associated with the socket reader.
     */
    protected Session session;
    /**
     * Reference to the physical connection.
     */
    protected SocketConnection connection;
    /**
     * Server name for which we are attending clients.
     */
    protected String serverName;

    /**
     * Router used to route incoming packets to the correct channels.
     */
    private PacketRouter router;
    /**
     * Routing table used for checking whether a domain is known or not.
     */
    private RoutingTable routingTable;
    /**
     * Specifies whether the socket is using blocking or non-blocking connections.
     */
    private SocketReadingMode readingMode;
    XMPPPacketReader reader = null;
    protected boolean open;

    static {
        try {
            factory = XmlPullParserFactory.newInstance(MXParser.class.getName(), null);
        }
        catch (XmlPullParserException e) {
            Log.error("Error creating a parser factory", e);
        }
    }

    /**
     * Creates a dedicated reader for a socket.
     *
     * @param router the router for sending packets that were read.
     * @param routingTable the table that keeps routes to registered services.
     * @param serverName the name of the server this socket is working for.
     * @param socket the socket to read from.
     * @param connection the connection being read.
     * @param useBlockingMode true means that the server will use a thread per connection.
     */
    public SocketReader(PacketRouter router, RoutingTable routingTable, String serverName,
            Socket socket, SocketConnection connection, boolean useBlockingMode) {
        this.serverName = serverName;
        this.router = router;
        this.routingTable = routingTable;
        this.connection = connection;

        connection.setSocketReader(this);

        // Reader is associated with a new XMPPPacketReader
        reader = new XMPPPacketReader();
        reader.setXPPFactory(factory);

        // Set the blocking reading mode to use
        if (useBlockingMode) {
            readingMode = new BlockingReadingMode(socket, this);
        }
        else {
            readingMode = new NonBlockingReadingMode(socket, this);
        }
    }

    /**
     * A dedicated thread loop for reading the stream and sending incoming
     * packets to the appropriate router.
     */
    public void run() {
        readingMode.run();
    }

    protected void process(Element doc) throws Exception {
        if (doc == null) {
            return;
        }

        String tag = doc.getName();
        if ("message".equals(tag)) {
            Message packet;
            try {
                packet = new Message(doc);
            }
            catch(IllegalArgumentException e) {
                Log.debug("Rejecting packet. JID malformed", e);
                // The original packet contains a malformed JID so answer with an error.
                Message reply = new Message();
                reply.setID(doc.attributeValue("id"));
                reply.setTo(session.getAddress());
                reply.getElement().addAttribute("from", doc.attributeValue("to"));
                reply.setError(PacketError.Condition.jid_malformed);
                session.process(reply);
                return;
            }
            processMessage(packet);
        }
        else if ("presence".equals(tag)) {
            Presence packet;
            try {
                packet = new Presence(doc);
            }
            catch (IllegalArgumentException e) {
                Log.debug("Rejecting packet. JID malformed", e);
                // The original packet contains a malformed JID so answer an error
                Presence reply = new Presence();
                reply.setID(doc.attributeValue("id"));
                reply.setTo(session.getAddress());
                reply.getElement().addAttribute("from", doc.attributeValue("to"));
                reply.setError(PacketError.Condition.jid_malformed);
                session.process(reply);
                return;
            }
            // Check that the presence type is valid. If not then assume available type
            try {
                packet.getType();
            }
            catch (IllegalArgumentException e) {
                Log.warn("Invalid presence type", e);
                // The presence packet contains an invalid presence type so replace it with
                // an available presence type
                packet.setType(null);
            }
            // Check that the presence show is valid. If not then assume available show value
            try {
                packet.getShow();
            }
            catch (IllegalArgumentException e) {
                Log.warn("Invalid presence show", e);
                // The presence packet contains an invalid presence show so replace it with
                // an available presence show
                packet.setShow(null);
            }
            if (session.getStatus() == Session.STATUS_CLOSED && packet.isAvailable()) {
                // Ignore available presence packets sent from a closed session. A closed
                // session may have buffered data pending to be processes so we want to ignore
                // just Presences of type available
                Log.warn("Ignoring available presence packet of closed session: " + packet);
                return;
            }
            processPresence(packet);
        }
        else if ("iq".equals(tag)) {
            IQ packet;
            try {
                packet = getIQ(doc);
            }
            catch(IllegalArgumentException e) {
                Log.debug("Rejecting packet. JID malformed", e);
                // The original packet contains a malformed JID so answer an error
                IQ reply = new IQ();
                if (!doc.elements().isEmpty()) {
                    reply.setChildElement(((Element) doc.elements().get(0)).createCopy());
                }
                reply.setID(doc.attributeValue("id"));
                reply.setTo(session.getAddress());
                if (doc.attributeValue("to") != null) {
                    reply.getElement().addAttribute("from", doc.attributeValue("to"));
                }
                reply.setError(PacketError.Condition.jid_malformed);
                session.process(reply);
                return;
            }
            processIQ(packet);
        }
        else
        {
            if (!processUnknowPacket(doc)) {
                Log.warn(LocaleUtils.getLocalizedString("admin.error.packet.tag") +
                        doc.asXML());
                open = false;
            }
        }
    }

    /**
     * Process the received IQ packet. Registered
     * {@link org.jivesoftware.wildfire.interceptor.PacketInterceptor} will be invoked before
     * and after the packet was routed.<p>
     *
     * Subclasses may redefine this method for different reasons such as modifying the sender
     * of the packet to avoid spoofing, rejecting the packet or even process the packet in
     * another thread.
     *
     * @param packet the received packet.
     */
    protected void processIQ(IQ packet) throws UnauthorizedException {
        // Ensure that connection was secured if TLS was required
        if (connection.getTlsPolicy() == Connection.TLSPolicy.required &&
                !connection.isSecure()) {
            closeNeverSecuredConnection();
            return;
        }
        try {
            // Invoke the interceptors before we process the read packet
            InterceptorManager.getInstance().invokeInterceptors(packet, session, true,
                    false);
            router.route(packet);
            // Invoke the interceptors after we have processed the read packet
            InterceptorManager.getInstance().invokeInterceptors(packet, session, true,
                    true);
            session.incrementClientPacketCount();
        }
        catch (PacketRejectedException e) {
            // An interceptor rejected this packet so answer a not_allowed error
            IQ reply = new IQ();
            reply.setChildElement(packet.getChildElement().createCopy());
            reply.setID(packet.getID());
            reply.setTo(session.getAddress());
            reply.setFrom(packet.getTo());
            reply.setError(PacketError.Condition.not_allowed);
            session.process(reply);
            // Check if a message notifying the rejection should be sent
            if (e.getRejectionMessage() != null && e.getRejectionMessage().trim().length() > 0) {
                // A message for the rejection will be sent to the sender of the rejected packet
                Message notification = new Message();
                notification.setTo(session.getAddress());
                notification.setFrom(packet.getTo());
                notification.setBody(e.getRejectionMessage());
                session.process(notification);
            }
        }
    }