2 * Copyright (c) 2013 Cisco Systems, Inc. and others. All rights reserved.
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
8 package org.opendaylight.netconf.nettyutil;
10 import static com.google.common.base.Preconditions.checkArgument;
11 import static com.google.common.base.Preconditions.checkState;
12 import static java.util.Objects.requireNonNull;
14 import com.google.common.annotations.Beta;
15 import io.netty.channel.Channel;
16 import io.netty.channel.ChannelHandler;
17 import io.netty.channel.ChannelHandlerContext;
18 import io.netty.channel.ChannelInboundHandlerAdapter;
19 import io.netty.handler.ssl.SslHandler;
20 import io.netty.util.Timeout;
21 import io.netty.util.Timer;
22 import io.netty.util.concurrent.Future;
23 import io.netty.util.concurrent.Promise;
24 import java.util.concurrent.TimeUnit;
25 import org.checkerframework.checker.index.qual.NonNegative;
26 import org.checkerframework.checker.lock.qual.GuardedBy;
27 import org.checkerframework.checker.lock.qual.Holding;
28 import org.eclipse.jdt.annotation.NonNull;
29 import org.eclipse.jdt.annotation.Nullable;
30 import org.opendaylight.netconf.api.CapabilityURN;
31 import org.opendaylight.netconf.api.NamespaceURN;
32 import org.opendaylight.netconf.api.NetconfDocumentedException;
33 import org.opendaylight.netconf.api.NetconfSessionListener;
34 import org.opendaylight.netconf.api.messages.HelloMessage;
35 import org.opendaylight.netconf.api.messages.NetconfMessage;
36 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
37 import org.opendaylight.netconf.nettyutil.handler.ChunkedFramingMechanismEncoder;
38 import org.opendaylight.netconf.nettyutil.handler.NetconfChunkAggregator;
39 import org.opendaylight.netconf.nettyutil.handler.NetconfMessageToXMLEncoder;
40 import org.opendaylight.netconf.nettyutil.handler.NetconfXMLToHelloMessageDecoder;
41 import org.opendaylight.netconf.nettyutil.handler.NetconfXMLToMessageDecoder;
42 import org.slf4j.Logger;
43 import org.slf4j.LoggerFactory;
44 import org.w3c.dom.Document;
45 import org.w3c.dom.NodeList;
47 public abstract class AbstractNetconfSessionNegotiator<S extends AbstractNetconfSession<S, L>,
48 L extends NetconfSessionListener<S>>
49 extends ChannelInboundHandlerAdapter implements NetconfSessionNegotiator<S> {
51 * Possible states for Finite State Machine.
53 protected enum State {
54 IDLE, OPEN_WAIT, FAILED, ESTABLISHED
57 private static final Logger LOG = LoggerFactory.getLogger(AbstractNetconfSessionNegotiator.class);
58 private static final String NAME_OF_EXCEPTION_HANDLER = "lastExceptionHandler";
59 private static final String DEFAULT_MAXIMUM_CHUNK_SIZE_PROP = "org.opendaylight.netconf.default.maximum.chunk.size";
60 private static final int DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT = 16 * 1024 * 1024;
63 * Default upper bound on the size of an individual chunk. This value can be controlled through
64 * {@value #DEFAULT_MAXIMUM_CHUNK_SIZE_PROP} system property and defaults to
65 * {@value #DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT} bytes.
68 public static final @NonNegative int DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE;
71 final int propValue = Integer.getInteger(DEFAULT_MAXIMUM_CHUNK_SIZE_PROP, DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT);
73 LOG.warn("Ignoring invalid {} value {}", DEFAULT_MAXIMUM_CHUNK_SIZE_PROP, propValue);
74 DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE = DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT;
76 DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE = propValue;
78 LOG.debug("Default maximum incoming NETCONF chunk size is {} bytes", DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE);
81 private final @NonNull HelloMessage localHello;
82 protected final Channel channel;
84 private final @NonNegative int maximumIncomingChunkSize;
85 private final long connectionTimeoutMillis;
86 private final Promise<S> promise;
87 private final L sessionListener;
88 private final Timer timer;
91 private Timeout timeoutTask;
93 private State state = State.IDLE;
95 protected AbstractNetconfSessionNegotiator(final HelloMessage hello, final Promise<S> promise,
96 final Channel channel, final Timer timer, final L sessionListener,
97 final long connectionTimeoutMillis,
98 final @NonNegative int maximumIncomingChunkSize) {
99 localHello = requireNonNull(hello);
100 this.promise = requireNonNull(promise);
101 this.channel = requireNonNull(channel);
103 this.sessionListener = sessionListener;
104 this.connectionTimeoutMillis = connectionTimeoutMillis;
105 this.maximumIncomingChunkSize = maximumIncomingChunkSize;
106 checkArgument(maximumIncomingChunkSize > 0, "Invalid maximum incoming chunk size %s", maximumIncomingChunkSize);
109 protected final @NonNull HelloMessage localHello() {
113 protected final void startNegotiation() {
114 if (ifNegotiatedAlready()) {
115 LOG.debug("Negotiation on channel {} already started", channel);
117 final var sslHandler = getSslHandler(channel);
118 if (sslHandler != null) {
119 sslHandler.handshakeFuture().addListener(future -> {
120 checkState(future.isSuccess(), "Ssl handshake was not successful");
121 LOG.debug("Ssl handshake complete");
130 protected final boolean ifNegotiatedAlready() {
131 // Indicates whether negotiation already started
132 return state() != State.IDLE;
135 private synchronized State state() {
139 private static @Nullable SslHandler getSslHandler(final Channel channel) {
140 return channel.pipeline().get(SslHandler.class);
143 private void start() {
144 LOG.debug("Sending negotiation proposal {} on channel {}", localHello, channel);
146 // Send the message out, but to not run listeners just yet, as we have some more state transitions to go through
147 final var helloFuture = channel.writeAndFlush(localHello);
149 // Quick check: if the future has already failed we call it quits before negotiation even started
150 final var helloCause = helloFuture.cause();
151 if (helloCause != null) {
152 LOG.warn("Failed to send negotiation proposal on channel {}", channel, helloCause);
157 // Catch any exceptions from this point on. Use a named class to ease debugging.
158 final class ExceptionHandlingInboundChannelHandler extends ChannelInboundHandlerAdapter {
160 public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
161 LOG.warn("An exception occurred during negotiation with {} on channel {}",
162 channel.remoteAddress(), channel, cause);
163 // FIXME: this is quite suspect as it is competing with timeoutExpired() without synchronization
165 negotiationFailed(cause);
166 changeState(State.FAILED);
170 channel.pipeline().addLast(NAME_OF_EXCEPTION_HANDLER, new ExceptionHandlingInboundChannelHandler());
172 // Remove special outbound handler for hello message. Insert regular netconf xml message (en|de)coders.
173 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_ENCODER,
174 new NetconfMessageToXMLEncoder());
176 synchronized (this) {
177 lockedChangeState(State.OPEN_WAIT);
179 // Service the timeout on channel's eventloop, so that we do not get state transition problems
180 timeoutTask = timer.newTimeout(unused -> channel.eventLoop().execute(this::timeoutExpired),
181 connectionTimeoutMillis, TimeUnit.MILLISECONDS);
184 LOG.debug("Session negotiation started on channel {}", channel);
186 // State transition completed, now run any additional processing
187 helloFuture.addListener(this::onHelloWriteComplete);
190 private void onHelloWriteComplete(final Future<?> future) {
191 final var cause = future.cause();
193 LOG.info("Failed to send message {} on channel {}", localHello, channel, cause);
194 negotiationFailed(cause);
196 LOG.trace("Message {} sent to socket on channel {}", localHello, channel);
200 private synchronized void timeoutExpired() {
201 if (timeoutTask == null) {
202 // cancelTimeout() between expiry and execution on the loop
207 if (state != State.ESTABLISHED) {
208 LOG.debug("Connection timeout after {}ms, session backed by channel {} is in state {}",
209 connectionTimeoutMillis, channel, state);
211 // Do not fail negotiation if promise is done or canceled
212 // It would result in setting result of the promise second time and that throws exception
213 if (!promise.isDone() && !promise.isCancelled()) {
214 LOG.warn("Netconf session backed by channel {} was not established after {}", channel,
215 connectionTimeoutMillis);
218 } else if (channel.isOpen()) {
219 channel.pipeline().remove(NAME_OF_EXCEPTION_HANDLER);
223 private void failAndClose() {
224 changeState(State.FAILED);
225 channel.close().addListener(this::onChannelClosed);
228 private void onChannelClosed(final Future<?> future) {
229 final var cause = future.cause();
231 LOG.warn("Channel {} closed: fail", channel, cause);
233 LOG.debug("Channel {} closed: success", channel);
237 private synchronized void cancelTimeout() {
238 if (timeoutTask != null && !timeoutTask.cancel()) {
239 // Late-coming cancel: make sure the task does not actually run
244 protected final S getSessionForHelloMessage(final HelloMessage netconfMessage)
245 throws NetconfDocumentedException {
246 final Document doc = netconfMessage.getDocument();
248 if (shouldUseChunkFraming(doc)) {
249 insertChunkFramingToPipeline();
252 changeState(State.ESTABLISHED);
253 return getSession(sessionListener, channel, netconfMessage);
256 protected abstract S getSession(L sessionListener, Channel channel, HelloMessage message)
257 throws NetconfDocumentedException;
260 * Insert chunk framing handlers into the pipeline.
262 private void insertChunkFramingToPipeline() {
263 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_FRAME_ENCODER,
264 new ChunkedFramingMechanismEncoder());
265 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_AGGREGATOR,
266 new NetconfChunkAggregator(maximumIncomingChunkSize));
269 private boolean shouldUseChunkFraming(final Document doc) {
270 return containsBase11Capability(doc) && containsBase11Capability(localHello.getDocument());
274 * Remove special inbound handler for hello message. Insert regular netconf xml message (en|de)coders.
277 * Inbound hello message handler should be kept until negotiation is successful
278 * It caches any non-hello messages while negotiation is still in progress
280 protected final void replaceHelloMessageInboundHandler(final S session) {
281 ChannelHandler helloMessageHandler = replaceChannelHandler(channel,
282 AbstractChannelInitializer.NETCONF_MESSAGE_DECODER, new NetconfXMLToMessageDecoder());
284 checkState(helloMessageHandler instanceof NetconfXMLToHelloMessageDecoder,
285 "Pipeline handlers misplaced on session: %s, pipeline: %s", session, channel.pipeline());
286 Iterable<NetconfMessage> netconfMessagesFromNegotiation =
287 ((NetconfXMLToHelloMessageDecoder) helloMessageHandler).getPostHelloNetconfMessages();
289 // Process messages received during negotiation
290 // The hello message handler does not have to be synchronized,
291 // since it is always call from the same thread by netty.
292 // It means, we are now using the thread now
293 for (NetconfMessage message : netconfMessagesFromNegotiation) {
294 session.handleMessage(message);
298 private static ChannelHandler replaceChannelHandler(final Channel channel, final String handlerKey,
299 final ChannelHandler decoder) {
300 return channel.pipeline().replace(handlerKey, handlerKey, decoder);
303 private synchronized void changeState(final State newState) {
304 lockedChangeState(newState);
308 private void lockedChangeState(final State newState) {
309 LOG.debug("Changing state from : {} to : {} for channel: {}", state, newState, channel);
310 checkState(isStateChangePermitted(state, newState),
311 "Cannot change state from %s to %s for channel %s", state, newState, channel);
315 private static boolean containsBase11Capability(final Document doc) {
316 final NodeList nList = doc.getElementsByTagNameNS(NamespaceURN.BASE, XmlNetconfConstants.CAPABILITY);
317 for (int i = 0; i < nList.getLength(); i++) {
318 if (nList.item(i).getTextContent().contains(CapabilityURN.BASE_1_1)) {
325 private static boolean isStateChangePermitted(final State state, final State newState) {
326 if (state == State.IDLE && (newState == State.OPEN_WAIT || newState == State.FAILED)) {
329 if (state == State.OPEN_WAIT && (newState == State.ESTABLISHED || newState == State.FAILED)) {
332 LOG.debug("Transition from {} to {} is not allowed", state, newState);
336 protected final void negotiationSuccessful(final S session) {
337 LOG.debug("Negotiation on channel {} successful with session {}", channel, session);
338 channel.pipeline().replace(this, "session", session);
339 promise.setSuccess(session);
342 protected void negotiationFailed(final Throwable cause) {
343 LOG.debug("Negotiation on channel {} failed", channel, cause);
345 promise.setFailure(cause);
349 @SuppressWarnings("checkstyle:illegalCatch")
350 public final void channelActive(final ChannelHandlerContext ctx) {
351 LOG.debug("Starting session negotiation on channel {}", channel);
354 } catch (final Exception e) {
355 LOG.warn("Unexpected negotiation failure on channel {}", channel, e);
356 negotiationFailed(e);
361 @SuppressWarnings("checkstyle:illegalCatch")
362 public final void channelRead(final ChannelHandlerContext ctx, final Object msg) {
363 if (state() == State.FAILED) {
364 // We have already failed -- do not process any more messages
368 LOG.debug("Negotiation read invoked on channel {}", channel);
370 handleMessage((HelloMessage) msg);
371 } catch (final Exception e) {
372 LOG.debug("Unexpected error while handling negotiation message {} on channel {}", msg, channel, e);
373 negotiationFailed(e);
378 public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
379 LOG.info("Unexpected error during negotiation on channel {}", channel, cause);
380 negotiationFailed(cause);
383 protected abstract void handleMessage(HelloMessage msg) throws Exception;