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.Promise;
23 import java.util.concurrent.TimeUnit;
24 import org.checkerframework.checker.index.qual.NonNegative;
25 import org.checkerframework.checker.lock.qual.GuardedBy;
26 import org.checkerframework.checker.lock.qual.Holding;
27 import org.eclipse.jdt.annotation.NonNull;
28 import org.eclipse.jdt.annotation.Nullable;
29 import org.opendaylight.netconf.api.NetconfDocumentedException;
30 import org.opendaylight.netconf.api.NetconfMessage;
31 import org.opendaylight.netconf.api.NetconfSessionListener;
32 import org.opendaylight.netconf.api.messages.NetconfHelloMessage;
33 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
34 import org.opendaylight.netconf.nettyutil.handler.FramingMechanismHandlerFactory;
35 import org.opendaylight.netconf.nettyutil.handler.NetconfChunkAggregator;
36 import org.opendaylight.netconf.nettyutil.handler.NetconfMessageToXMLEncoder;
37 import org.opendaylight.netconf.nettyutil.handler.NetconfXMLToHelloMessageDecoder;
38 import org.opendaylight.netconf.nettyutil.handler.NetconfXMLToMessageDecoder;
39 import org.opendaylight.netconf.util.messages.FramingMechanism;
40 import org.slf4j.Logger;
41 import org.slf4j.LoggerFactory;
42 import org.w3c.dom.Document;
43 import org.w3c.dom.NodeList;
45 public abstract class AbstractNetconfSessionNegotiator<S extends AbstractNetconfSession<S, L>,
46 L extends NetconfSessionListener<S>>
47 extends ChannelInboundHandlerAdapter implements NetconfSessionNegotiator<S> {
49 * Possible states for Finite State Machine.
51 protected enum State {
52 IDLE, OPEN_WAIT, FAILED, ESTABLISHED
55 private static final Logger LOG = LoggerFactory.getLogger(AbstractNetconfSessionNegotiator.class);
56 private static final String NAME_OF_EXCEPTION_HANDLER = "lastExceptionHandler";
57 private static final String DEFAULT_MAXIMUM_CHUNK_SIZE_PROP = "org.opendaylight.netconf.default.maximum.chunk.size";
58 private static final int DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT = 16 * 1024 * 1024;
61 * Default upper bound on the size of an individual chunk. This value can be controlled through
62 * {@value #DEFAULT_MAXIMUM_CHUNK_SIZE_PROP} system property and defaults to
63 * {@value #DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT} bytes.
66 public static final @NonNegative int DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE;
69 final int propValue = Integer.getInteger(DEFAULT_MAXIMUM_CHUNK_SIZE_PROP, DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT);
71 LOG.warn("Ignoring invalid {} value {}", DEFAULT_MAXIMUM_CHUNK_SIZE_PROP, propValue);
72 DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE = DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT;
74 DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE = propValue;
76 LOG.debug("Default maximum incoming NETCONF chunk size is {} bytes", DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE);
79 private final @NonNull NetconfHelloMessage localHello;
80 protected final Channel channel;
82 private final @NonNegative int maximumIncomingChunkSize;
83 private final long connectionTimeoutMillis;
84 private final Promise<S> promise;
85 private final L sessionListener;
86 private final Timer timer;
89 private Timeout timeoutTask;
91 private State state = State.IDLE;
93 protected AbstractNetconfSessionNegotiator(final NetconfHelloMessage hello, final Promise<S> promise,
94 final Channel channel, final Timer timer, final L sessionListener,
95 final long connectionTimeoutMillis,
96 final @NonNegative int maximumIncomingChunkSize) {
97 this.localHello = requireNonNull(hello);
98 this.promise = requireNonNull(promise);
99 this.channel = requireNonNull(channel);
101 this.sessionListener = sessionListener;
102 this.connectionTimeoutMillis = connectionTimeoutMillis;
103 this.maximumIncomingChunkSize = maximumIncomingChunkSize;
104 checkArgument(maximumIncomingChunkSize > 0, "Invalid maximum incoming chunk size %s", maximumIncomingChunkSize);
107 @Deprecated(since = "4.0.1", forRemoval = true)
108 protected AbstractNetconfSessionNegotiator(final NetconfHelloMessage hello, final Promise<S> promise,
109 final Channel channel, final Timer timer,
110 final L sessionListener, final long connectionTimeoutMillis) {
111 this(hello, promise, channel, timer, sessionListener, connectionTimeoutMillis,
112 DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE);
115 protected final @NonNull NetconfHelloMessage localHello() {
119 protected final void startNegotiation() {
120 if (ifNegotiatedAlready()) {
121 LOG.debug("Negotiation on channel {} already started", channel);
123 final var sslHandler = getSslHandler(channel);
124 if (sslHandler != null) {
125 sslHandler.handshakeFuture().addListener(future -> {
126 checkState(future.isSuccess(), "Ssl handshake was not successful");
127 LOG.debug("Ssl handshake complete");
136 protected final synchronized boolean ifNegotiatedAlready() {
137 // Indicates whether negotiation already started
138 return this.state != State.IDLE;
141 private static @Nullable SslHandler getSslHandler(final Channel channel) {
142 return channel.pipeline().get(SslHandler.class);
145 private void start() {
146 LOG.debug("Session negotiation started with hello message {} on channel {}", localHello, channel);
148 channel.pipeline().addLast(NAME_OF_EXCEPTION_HANDLER, new ExceptionHandlingInboundChannelHandler());
150 sendMessage(localHello);
152 replaceHelloMessageOutboundHandler();
154 synchronized (this) {
155 lockedChangeState(State.OPEN_WAIT);
157 // Service the timeout on channel's eventloop, so that we do not get state transition problems
158 timeoutTask = timer.newTimeout(unused -> channel.eventLoop().execute(this::timeoutExpired),
159 connectionTimeoutMillis, TimeUnit.MILLISECONDS);
163 private synchronized void timeoutExpired() {
164 if (timeoutTask == null) {
165 // cancelTimeout() between expiry and execution on the loop
170 if (state != State.ESTABLISHED) {
171 LOG.debug("Connection timeout after {}ms, session backed by channel {} is in state {}",
172 connectionTimeoutMillis, channel, state);
174 // Do not fail negotiation if promise is done or canceled
175 // It would result in setting result of the promise second time and that throws exception
176 if (!promise.isDone() && !promise.isCancelled()) {
177 LOG.warn("Netconf session backed by channel {} was not established after {}", channel,
178 connectionTimeoutMillis);
179 changeState(State.FAILED);
181 channel.close().addListener(future -> {
182 final var cause = future.cause();
184 LOG.warn("Channel {} closed: fail", channel, cause);
186 LOG.debug("Channel {} closed: success", channel);
190 } else if (channel.isOpen()) {
191 channel.pipeline().remove(NAME_OF_EXCEPTION_HANDLER);
195 private synchronized void cancelTimeout() {
196 if (timeoutTask != null && !timeoutTask.cancel()) {
197 // Late-coming cancel: make sure the task does not actually run
202 protected final S getSessionForHelloMessage(final NetconfHelloMessage netconfMessage)
203 throws NetconfDocumentedException {
204 final Document doc = netconfMessage.getDocument();
206 if (shouldUseChunkFraming(doc)) {
207 insertChunkFramingToPipeline();
210 changeState(State.ESTABLISHED);
211 return getSession(sessionListener, channel, netconfMessage);
214 protected abstract S getSession(L sessionListener, Channel channel, NetconfHelloMessage message)
215 throws NetconfDocumentedException;
218 * Insert chunk framing handlers into the pipeline.
220 private void insertChunkFramingToPipeline() {
221 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_FRAME_ENCODER,
222 FramingMechanismHandlerFactory.createHandler(FramingMechanism.CHUNK));
223 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_AGGREGATOR,
224 new NetconfChunkAggregator(maximumIncomingChunkSize));
227 private boolean shouldUseChunkFraming(final Document doc) {
228 return containsBase11Capability(doc) && containsBase11Capability(localHello.getDocument());
232 * Remove special inbound handler for hello message. Insert regular netconf xml message (en|de)coders.
235 * Inbound hello message handler should be kept until negotiation is successful
236 * It caches any non-hello messages while negotiation is still in progress
238 protected final void replaceHelloMessageInboundHandler(final S session) {
239 ChannelHandler helloMessageHandler = replaceChannelHandler(channel,
240 AbstractChannelInitializer.NETCONF_MESSAGE_DECODER, new NetconfXMLToMessageDecoder());
242 checkState(helloMessageHandler instanceof NetconfXMLToHelloMessageDecoder,
243 "Pipeline handlers misplaced on session: %s, pipeline: %s", session, channel.pipeline());
244 Iterable<NetconfMessage> netconfMessagesFromNegotiation =
245 ((NetconfXMLToHelloMessageDecoder) helloMessageHandler).getPostHelloNetconfMessages();
247 // Process messages received during negotiation
248 // The hello message handler does not have to be synchronized,
249 // since it is always call from the same thread by netty.
250 // It means, we are now using the thread now
251 for (NetconfMessage message : netconfMessagesFromNegotiation) {
252 session.handleMessage(message);
257 * Remove special outbound handler for hello message. Insert regular netconf xml message (en|de)coders.
259 private void replaceHelloMessageOutboundHandler() {
260 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_ENCODER,
261 new NetconfMessageToXMLEncoder());
264 private static ChannelHandler replaceChannelHandler(final Channel channel, final String handlerKey,
265 final ChannelHandler decoder) {
266 return channel.pipeline().replace(handlerKey, handlerKey, decoder);
269 private synchronized void changeState(final State newState) {
270 lockedChangeState(newState);
274 private void lockedChangeState(final State newState) {
275 LOG.debug("Changing state from : {} to : {} for channel: {}", state, newState, channel);
276 checkState(isStateChangePermitted(state, newState),
277 "Cannot change state from %s to %s for channel %s", state, newState, channel);
278 this.state = newState;
281 private static boolean containsBase11Capability(final Document doc) {
282 final NodeList nList = doc.getElementsByTagNameNS(
283 XmlNetconfConstants.URN_IETF_PARAMS_XML_NS_NETCONF_BASE_1_0,
284 XmlNetconfConstants.CAPABILITY);
285 for (int i = 0; i < nList.getLength(); i++) {
286 if (nList.item(i).getTextContent().contains(XmlNetconfConstants.URN_IETF_PARAMS_NETCONF_BASE_1_1)) {
293 private static boolean isStateChangePermitted(final State state, final State newState) {
294 if (state == State.IDLE && newState == State.OPEN_WAIT) {
297 if (state == State.OPEN_WAIT && newState == State.ESTABLISHED) {
300 if (state == State.OPEN_WAIT && newState == State.FAILED) {
303 LOG.debug("Transition from {} to {} is not allowed", state, newState);
308 * Handler to catch exceptions in pipeline during negotiation.
310 private final class ExceptionHandlingInboundChannelHandler extends ChannelInboundHandlerAdapter {
312 public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
313 LOG.warn("An exception occurred during negotiation with {} on channel {}",
314 channel.remoteAddress(), channel, cause);
315 // FIXME: this is quite suspect as it is competing with timeoutExpired() without synchronization
317 negotiationFailed(cause);
318 changeState(State.FAILED);
322 protected final void negotiationSuccessful(final S session) {
323 LOG.debug("Negotiation on channel {} successful with session {}", channel, session);
324 channel.pipeline().replace(this, "session", session);
325 promise.setSuccess(session);
328 protected void negotiationFailed(final Throwable cause) {
329 LOG.debug("Negotiation on channel {} failed", channel, cause);
331 promise.setFailure(cause);
335 * Send a message to peer and fail negotiation if it does not reach
338 * @param msg Message which should be sent.
340 protected void sendMessage(final NetconfMessage msg) {
341 channel.writeAndFlush(msg).addListener(f -> {
342 final var cause = f.cause();
344 LOG.info("Failed to send message {} on channel {}", msg, channel, cause);
345 negotiationFailed(cause);
347 LOG.trace("Message {} sent to socket on channel {}", msg, channel);
353 @SuppressWarnings("checkstyle:illegalCatch")
354 public final void channelActive(final ChannelHandlerContext ctx) {
355 LOG.debug("Starting session negotiation on channel {}", channel);
358 } catch (final Exception e) {
359 LOG.warn("Unexpected negotiation failure on channel {}", channel, e);
360 negotiationFailed(e);
365 @SuppressWarnings("checkstyle:illegalCatch")
366 public final void channelRead(final ChannelHandlerContext ctx, final Object msg) {
367 LOG.debug("Negotiation read invoked on channel {}", channel);
369 handleMessage((NetconfHelloMessage) msg);
370 } catch (final Exception e) {
371 LOG.debug("Unexpected error while handling negotiation message {} on channel {}", msg, channel, e);
372 negotiationFailed(e);
377 public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
378 LOG.info("Unexpected error during negotiation on channel {}", channel, cause);
379 negotiationFailed(cause);
382 protected abstract void handleMessage(NetconfHelloMessage msg) throws Exception;