--- /dev/null
+/*
+ * Copyright (c) 2013 Cisco Systems, Inc. and others. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.opendaylight.netconf.nettyutil;
+
+import com.google.common.base.Optional;
+import com.google.common.base.Preconditions;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+import io.netty.handler.ssl.SslHandler;
+import io.netty.util.Timeout;
+import io.netty.util.Timer;
+import io.netty.util.TimerTask;
+import io.netty.util.concurrent.Future;
+import io.netty.util.concurrent.GenericFutureListener;
+import io.netty.util.concurrent.Promise;
+import java.util.concurrent.TimeUnit;
+import org.opendaylight.netconf.api.NetconfDocumentedException;
+import org.opendaylight.netconf.api.NetconfMessage;
+import org.opendaylight.netconf.api.NetconfSessionListener;
+import org.opendaylight.netconf.api.NetconfSessionPreferences;
+import org.opendaylight.netconf.api.messages.NetconfHelloMessage;
+import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
+import org.opendaylight.netconf.nettyutil.handler.FramingMechanismHandlerFactory;
+import org.opendaylight.netconf.nettyutil.handler.NetconfChunkAggregator;
+import org.opendaylight.netconf.nettyutil.handler.NetconfMessageToXMLEncoder;
+import org.opendaylight.netconf.nettyutil.handler.NetconfXMLToHelloMessageDecoder;
+import org.opendaylight.netconf.nettyutil.handler.NetconfXMLToMessageDecoder;
+import org.opendaylight.netconf.util.messages.FramingMechanism;
+import org.opendaylight.protocol.framework.AbstractSessionNegotiator;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.w3c.dom.Document;
+import org.w3c.dom.NodeList;
+
+public abstract class AbstractNetconfSessionNegotiator<P extends NetconfSessionPreferences,
+ S extends AbstractNetconfSession<S, L>, L extends NetconfSessionListener<S>>
+ extends AbstractSessionNegotiator<NetconfHelloMessage, S> {
+
+ private static final Logger LOG = LoggerFactory.getLogger(AbstractNetconfSessionNegotiator.class);
+
+ public static final String NAME_OF_EXCEPTION_HANDLER = "lastExceptionHandler";
+
+ protected final P sessionPreferences;
+
+ private final L sessionListener;
+ private Timeout timeout;
+
+ /**
+ * Possible states for Finite State Machine.
+ */
+ protected enum State {
+ IDLE, OPEN_WAIT, FAILED, ESTABLISHED
+ }
+
+ private State state = State.IDLE;
+ private final Promise<S> promise;
+ private final Timer timer;
+ private final long connectionTimeoutMillis;
+
+ protected AbstractNetconfSessionNegotiator(final P sessionPreferences, final Promise<S> promise,
+ final Channel channel, final Timer timer,
+ final L sessionListener, final long connectionTimeoutMillis) {
+ super(promise, channel);
+ this.sessionPreferences = sessionPreferences;
+ this.promise = promise;
+ this.timer = timer;
+ this.sessionListener = sessionListener;
+ this.connectionTimeoutMillis = connectionTimeoutMillis;
+ }
+
+ @Override
+ protected final void startNegotiation() {
+ final Optional<SslHandler> sslHandler = getSslHandler(channel);
+ if (sslHandler.isPresent()) {
+ Future<Channel> future = sslHandler.get().handshakeFuture();
+ future.addListener(new GenericFutureListener<Future<? super Channel>>() {
+ @Override
+ public void operationComplete(final Future<? super Channel> future) {
+ Preconditions.checkState(future.isSuccess(), "Ssl handshake was not successful");
+ LOG.debug("Ssl handshake complete");
+ start();
+ }
+ });
+ } else {
+ start();
+ }
+ }
+
+ private static Optional<SslHandler> getSslHandler(final Channel channel) {
+ final SslHandler sslHandler = channel.pipeline().get(SslHandler.class);
+ return sslHandler == null ? Optional.<SslHandler>absent() : Optional.of(sslHandler);
+ }
+
+ public P getSessionPreferences() {
+ return sessionPreferences;
+ }
+
+ private void start() {
+ final NetconfHelloMessage helloMessage = this.sessionPreferences.getHelloMessage();
+ LOG.debug("Session negotiation started with hello message {} on channel {}", helloMessage, channel);
+
+ channel.pipeline().addLast(NAME_OF_EXCEPTION_HANDLER, new ExceptionHandlingInboundChannelHandler());
+
+ sendMessage(helloMessage);
+
+ replaceHelloMessageOutboundHandler();
+ changeState(State.OPEN_WAIT);
+
+ timeout = this.timer.newTimeout(new TimerTask() {
+ @Override
+ public void run(final Timeout timeout) {
+ synchronized (this) {
+ if (state != State.ESTABLISHED) {
+
+ LOG.debug("Connection timeout after {}, session is in state {}", timeout, state);
+
+ // Do not fail negotiation if promise is done or canceled
+ // It would result in setting result of the promise second time and that throws exception
+ if (isPromiseFinished() == false) {
+ LOG.warn("Netconf session was not established after {}", connectionTimeoutMillis);
+ changeState(State.FAILED);
+
+ channel.close().addListener(new GenericFutureListener<ChannelFuture>() {
+ @Override
+ public void operationComplete(final ChannelFuture future) throws Exception {
+ if (future.isSuccess()) {
+ LOG.debug("Channel {} closed: success", future.channel());
+ } else {
+ LOG.warn("Channel {} closed: fail", future.channel());
+ }
+ }
+ });
+ }
+ } else if (channel.isOpen()) {
+ channel.pipeline().remove(NAME_OF_EXCEPTION_HANDLER);
+ }
+ }
+ }
+
+ private boolean isPromiseFinished() {
+ return promise.isDone() || promise.isCancelled();
+ }
+
+ }, connectionTimeoutMillis, TimeUnit.MILLISECONDS);
+ }
+
+ private void cancelTimeout() {
+ if (timeout != null) {
+ timeout.cancel();
+ }
+ }
+
+ protected final S getSessionForHelloMessage(final NetconfHelloMessage netconfMessage)
+ throws NetconfDocumentedException {
+ Preconditions.checkNotNull(netconfMessage, "netconfMessage");
+
+ final Document doc = netconfMessage.getDocument();
+
+ if (shouldUseChunkFraming(doc)) {
+ insertChunkFramingToPipeline();
+ }
+
+ changeState(State.ESTABLISHED);
+ return getSession(sessionListener, channel, netconfMessage);
+ }
+
+ /**
+ * Insert chunk framing handlers into the pipeline.
+ */
+ private void insertChunkFramingToPipeline() {
+ replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_FRAME_ENCODER,
+ FramingMechanismHandlerFactory.createHandler(FramingMechanism.CHUNK));
+ replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_AGGREGATOR,
+ new NetconfChunkAggregator());
+ }
+
+ private boolean shouldUseChunkFraming(final Document doc) {
+ return containsBase11Capability(doc)
+ && containsBase11Capability(sessionPreferences.getHelloMessage().getDocument());
+ }
+
+ /**
+ * Remove special inbound handler for hello message. Insert regular netconf xml message (en|de)coders.
+ *
+ * <p>
+ * Inbound hello message handler should be kept until negotiation is successful
+ * It caches any non-hello messages while negotiation is still in progress
+ */
+ protected final void replaceHelloMessageInboundHandler(final S session) {
+ ChannelHandler helloMessageHandler = replaceChannelHandler(channel,
+ AbstractChannelInitializer.NETCONF_MESSAGE_DECODER, new NetconfXMLToMessageDecoder());
+
+ Preconditions.checkState(helloMessageHandler instanceof NetconfXMLToHelloMessageDecoder,
+ "Pipeline handlers misplaced on session: %s, pipeline: %s", session, channel.pipeline());
+ Iterable<NetconfMessage> netconfMessagesFromNegotiation =
+ ((NetconfXMLToHelloMessageDecoder) helloMessageHandler).getPostHelloNetconfMessages();
+
+ // Process messages received during negotiation
+ // The hello message handler does not have to be synchronized,
+ // since it is always call from the same thread by netty.
+ // It means, we are now using the thread now
+ for (NetconfMessage message : netconfMessagesFromNegotiation) {
+ session.handleMessage(message);
+ }
+ }
+
+ /**
+ * Remove special outbound handler for hello message. Insert regular netconf xml message (en|de)coders.
+ */
+ private void replaceHelloMessageOutboundHandler() {
+ replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_ENCODER,
+ new NetconfMessageToXMLEncoder());
+ }
+
+ private static ChannelHandler replaceChannelHandler(final Channel channel, final String handlerKey,
+ final ChannelHandler decoder) {
+ return channel.pipeline().replace(handlerKey, handlerKey, decoder);
+ }
+
+ protected abstract S getSession(L sessionListener, Channel channel, NetconfHelloMessage message)
+ throws NetconfDocumentedException;
+
+ private synchronized void changeState(final State newState) {
+ LOG.debug("Changing state from : {} to : {} for channel: {}", state, newState, channel);
+ Preconditions.checkState(isStateChangePermitted(state, newState),
+ "Cannot change state from %s to %s for chanel %s", state, newState, channel);
+ this.state = newState;
+ }
+
+ private static boolean containsBase11Capability(final Document doc) {
+ final NodeList nList = doc.getElementsByTagName(XmlNetconfConstants.CAPABILITY);
+ for (int i = 0; i < nList.getLength(); i++) {
+ if (nList.item(i).getTextContent().contains(XmlNetconfConstants.URN_IETF_PARAMS_NETCONF_BASE_1_1)) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ private static boolean isStateChangePermitted(final State state, final State newState) {
+ if (state == State.IDLE && newState == State.OPEN_WAIT) {
+ return true;
+ }
+ if (state == State.OPEN_WAIT && newState == State.ESTABLISHED) {
+ return true;
+ }
+ if (state == State.OPEN_WAIT && newState == State.FAILED) {
+ return true;
+ }
+ LOG.debug("Transition from {} to {} is not allowed", state, newState);
+ return false;
+ }
+
+ /**
+ * Handler to catch exceptions in pipeline during negotiation.
+ */
+ private final class ExceptionHandlingInboundChannelHandler extends ChannelInboundHandlerAdapter {
+ @Override
+ public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
+ LOG.warn("An exception occurred during negotiation with {}", channel.remoteAddress(), cause);
+ cancelTimeout();
+ negotiationFailed(cause);
+ changeState(State.FAILED);
+ }
+ }
+}
Code Review / transportpce.git / blobdiff