tests/honeynode/2.1/netconf-netty-util/src/main/java/org/opendaylight/netconf/nettyutil/AbstractNetconfSessionNegotiator.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.netconf.nettyutil;
  10
  11 import com.google.common.base.Optional;
  12 import com.google.common.base.Preconditions;
  13 import io.netty.channel.Channel;
  14 import io.netty.channel.ChannelFuture;
  15 import io.netty.channel.ChannelHandler;
  16 import io.netty.channel.ChannelHandlerContext;
  17 import io.netty.channel.ChannelInboundHandlerAdapter;
  18 import io.netty.handler.ssl.SslHandler;
  19 import io.netty.util.Timeout;
  20 import io.netty.util.Timer;
  21 import io.netty.util.TimerTask;
  22 import io.netty.util.concurrent.Future;
  23 import io.netty.util.concurrent.GenericFutureListener;
  24 import io.netty.util.concurrent.Promise;
  25 import java.util.concurrent.TimeUnit;
  26 import org.opendaylight.netconf.api.NetconfDocumentedException;
  27 import org.opendaylight.netconf.api.NetconfMessage;
  28 import org.opendaylight.netconf.api.NetconfSessionListener;
  29 import org.opendaylight.netconf.api.NetconfSessionPreferences;
  30 import org.opendaylight.netconf.api.messages.NetconfHelloMessage;
  31 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  32 import org.opendaylight.netconf.nettyutil.handler.FramingMechanismHandlerFactory;
  33 import org.opendaylight.netconf.nettyutil.handler.NetconfChunkAggregator;
  34 import org.opendaylight.netconf.nettyutil.handler.NetconfMessageToXMLEncoder;
  35 import org.opendaylight.netconf.nettyutil.handler.NetconfXMLToHelloMessageDecoder;
  36 import org.opendaylight.netconf.nettyutil.handler.NetconfXMLToMessageDecoder;
  37 import org.opendaylight.netconf.util.messages.FramingMechanism;
  38 import org.opendaylight.protocol.framework.AbstractSessionNegotiator;
  39 import org.slf4j.Logger;
  40 import org.slf4j.LoggerFactory;
  41 import org.w3c.dom.Document;
  42 import org.w3c.dom.NodeList;
  43
  44 public abstract class AbstractNetconfSessionNegotiator<P extends NetconfSessionPreferences,
  45         S extends AbstractNetconfSession<S, L>, L extends NetconfSessionListener<S>>
  46     extends AbstractSessionNegotiator<NetconfHelloMessage, S> {
  47
  48     private static final Logger LOG = LoggerFactory.getLogger(AbstractNetconfSessionNegotiator.class);
  49
  50     public static final String NAME_OF_EXCEPTION_HANDLER = "lastExceptionHandler";
  51
  52     protected final P sessionPreferences;
  53
  54     private final L sessionListener;
  55     private Timeout timeout;
  56
  57     /**
  58      * Possible states for Finite State Machine.
  59      */
  60     protected enum State {
  61         IDLE, OPEN_WAIT, FAILED, ESTABLISHED
  62     }
  63
  64     private State state = State.IDLE;
  65     private final Promise<S> promise;
  66     private final Timer timer;
  67     private final long connectionTimeoutMillis;
  68
  69     protected AbstractNetconfSessionNegotiator(final P sessionPreferences, final Promise<S> promise,
  70                                                final Channel channel, final Timer timer,
  71                                                final L sessionListener, final long connectionTimeoutMillis) {
  72         super(promise, channel);
  73         this.sessionPreferences = sessionPreferences;
  74         this.promise = promise;
  75         this.timer = timer;
  76         this.sessionListener = sessionListener;
  77         this.connectionTimeoutMillis = connectionTimeoutMillis;
  78     }
  79
  80     @Override
  81     protected final void startNegotiation() {
  82         final Optional<SslHandler> sslHandler = getSslHandler(channel);
  83         if (sslHandler.isPresent()) {
  84             Future<Channel> future = sslHandler.get().handshakeFuture();
  85             future.addListener(new GenericFutureListener<Future<? super Channel>>() {
  86                 @Override
  87                 public void operationComplete(final Future<? super Channel> future) {
  88                     Preconditions.checkState(future.isSuccess(), "Ssl handshake was not successful");
  89                     LOG.debug("Ssl handshake complete");
  90                     start();
  91                 }
  92             });
  93         } else {
  94             start();
  95         }
  96     }
  97
  98     private static Optional<SslHandler> getSslHandler(final Channel channel) {
  99         final SslHandler sslHandler = channel.pipeline().get(SslHandler.class);
 100         return sslHandler == null ? Optional.<SslHandler>absent() : Optional.of(sslHandler);
 101     }
 102
 103     public P getSessionPreferences() {
 104         return sessionPreferences;
 105     }
 106
 107     private void start() {
 108         final NetconfHelloMessage helloMessage = this.sessionPreferences.getHelloMessage();
 109         LOG.debug("Session negotiation started with hello message {} on channel {}", helloMessage, channel);
 110
 111         channel.pipeline().addLast(NAME_OF_EXCEPTION_HANDLER, new ExceptionHandlingInboundChannelHandler());
 112
 113         sendMessage(helloMessage);
 114
 115         replaceHelloMessageOutboundHandler();
 116         changeState(State.OPEN_WAIT);
 117
 118         timeout = this.timer.newTimeout(new TimerTask() {
 119             @Override
 120             public void run(final Timeout timeout) {
 121                 synchronized (this) {
 122                     if (state != State.ESTABLISHED) {
 123
 124                         LOG.debug("Connection timeout after {}, session is in state {}", timeout, state);
 125
 126                         // Do not fail negotiation if promise is done or canceled
 127                         // It would result in setting result of the promise second time and that throws exception
 128                         if (isPromiseFinished() == false) {
 129                             LOG.warn("Netconf session was not established after {}", connectionTimeoutMillis);
 130                             changeState(State.FAILED);
 131
 132                             channel.close().addListener(new GenericFutureListener<ChannelFuture>() {
 133                                 @Override
 134                                 public void operationComplete(final ChannelFuture future) throws Exception {
 135                                     if (future.isSuccess()) {
 136                                         LOG.debug("Channel {} closed: success", future.channel());
 137                                     } else {
 138                                         LOG.warn("Channel {} closed: fail", future.channel());
 139                                     }
 140                                 }
 141                             });
 142                         }
 143                     } else if (channel.isOpen()) {
 144                         channel.pipeline().remove(NAME_OF_EXCEPTION_HANDLER);
 145                     }
 146                 }
 147             }
 148
 149             private boolean isPromiseFinished() {
 150                 return promise.isDone() || promise.isCancelled();
 151             }
 152
 153         }, connectionTimeoutMillis, TimeUnit.MILLISECONDS);
 154     }
 155
 156     private void cancelTimeout() {
 157         if (timeout != null) {
 158             timeout.cancel();
 159         }
 160     }
 161
 162     protected final S getSessionForHelloMessage(final NetconfHelloMessage netconfMessage)
 163             throws NetconfDocumentedException {
 164         Preconditions.checkNotNull(netconfMessage, "netconfMessage");
 165
 166         final Document doc = netconfMessage.getDocument();
 167
 168         if (shouldUseChunkFraming(doc)) {
 169             insertChunkFramingToPipeline();
 170         }
 171
 172         changeState(State.ESTABLISHED);
 173         return getSession(sessionListener, channel, netconfMessage);
 174     }
 175
 176     /**
 177      * Insert chunk framing handlers into the pipeline.
 178      */
 179     private void insertChunkFramingToPipeline() {
 180         replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_FRAME_ENCODER,
 181                 FramingMechanismHandlerFactory.createHandler(FramingMechanism.CHUNK));
 182         replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_AGGREGATOR,
 183                 new NetconfChunkAggregator());
 184     }
 185
 186     private boolean shouldUseChunkFraming(final Document doc) {
 187         return containsBase11Capability(doc)
 188                 && containsBase11Capability(sessionPreferences.getHelloMessage().getDocument());
 189     }
 190
 191     /**
 192      * Remove special inbound handler for hello message. Insert regular netconf xml message (en|de)coders.
 193      *
 194      * <p>
 195      * Inbound hello message handler should be kept until negotiation is successful
 196      * It caches any non-hello messages while negotiation is still in progress
 197      */
 198     protected final void replaceHelloMessageInboundHandler(final S session) {
 199         ChannelHandler helloMessageHandler = replaceChannelHandler(channel,
 200                 AbstractChannelInitializer.NETCONF_MESSAGE_DECODER, new NetconfXMLToMessageDecoder());
 201
 202         Preconditions.checkState(helloMessageHandler instanceof NetconfXMLToHelloMessageDecoder,
 203                 "Pipeline handlers misplaced on session: %s, pipeline: %s", session, channel.pipeline());
 204         Iterable<NetconfMessage> netconfMessagesFromNegotiation =
 205                 ((NetconfXMLToHelloMessageDecoder) helloMessageHandler).getPostHelloNetconfMessages();
 206
 207         // Process messages received during negotiation
 208         // The hello message handler does not have to be synchronized,
 209         // since it is always call from the same thread by netty.
 210         // It means, we are now using the thread now
 211         for (NetconfMessage message : netconfMessagesFromNegotiation) {
 212             session.handleMessage(message);
 213         }
 214     }
 215
 216     /**
 217      * Remove special outbound handler for hello message. Insert regular netconf xml message (en|de)coders.
 218      */
 219     private void replaceHelloMessageOutboundHandler() {
 220         replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_ENCODER,
 221                 new NetconfMessageToXMLEncoder());
 222     }
 223
 224     private static ChannelHandler replaceChannelHandler(final Channel channel, final String handlerKey,
 225                                                         final ChannelHandler decoder) {
 226         return channel.pipeline().replace(handlerKey, handlerKey, decoder);
 227     }
 228
 229     protected abstract S getSession(L sessionListener, Channel channel, NetconfHelloMessage message)
 230             throws NetconfDocumentedException;
 231
 232     private synchronized void changeState(final State newState) {
 233         LOG.debug("Changing state from : {} to : {} for channel: {}", state, newState, channel);
 234         Preconditions.checkState(isStateChangePermitted(state, newState),
 235                 "Cannot change state from %s to %s for chanel %s", state, newState, channel);
 236         this.state = newState;
 237     }
 238
 239     private static boolean containsBase11Capability(final Document doc) {
 240         final NodeList nList = doc.getElementsByTagName(XmlNetconfConstants.CAPABILITY);
 241         for (int i = 0; i < nList.getLength(); i++) {
 242             if (nList.item(i).getTextContent().contains(XmlNetconfConstants.URN_IETF_PARAMS_NETCONF_BASE_1_1)) {
 243                 return true;
 244             }
 245         }
 246         return false;
 247     }
 248
 249     private static boolean isStateChangePermitted(final State state, final State newState) {
 250         if (state == State.IDLE && newState == State.OPEN_WAIT) {
 251             return true;
 252         }
 253         if (state == State.OPEN_WAIT && newState == State.ESTABLISHED) {
 254             return true;
 255         }
 256         if (state == State.OPEN_WAIT && newState == State.FAILED) {
 257             return true;
 258         }
 259         LOG.debug("Transition from {} to {} is not allowed", state, newState);
 260         return false;
 261     }
 262
 263     /**
 264      * Handler to catch exceptions in pipeline during negotiation.
 265      */
 266     private final class ExceptionHandlingInboundChannelHandler extends ChannelInboundHandlerAdapter {
 267         @Override
 268         public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
 269             LOG.warn("An exception occurred during negotiation with {}", channel.remoteAddress(), cause);
 270             cancelTimeout();
 271             negotiationFailed(cause);
 272             changeState(State.FAILED);
 273         }
 274     }
 275 }