/*
* 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 static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkState;
import static java.util.Objects.requireNonNull;
import com.google.common.annotations.Beta;
import io.netty.channel.Channel;
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.concurrent.Promise;
import java.util.concurrent.TimeUnit;
import org.checkerframework.checker.index.qual.NonNegative;
import org.checkerframework.checker.lock.qual.GuardedBy;
import org.checkerframework.checker.lock.qual.Holding;
import org.eclipse.jdt.annotation.NonNull;
import org.eclipse.jdt.annotation.Nullable;
import org.opendaylight.netconf.api.NetconfDocumentedException;
import org.opendaylight.netconf.api.NetconfMessage;
import org.opendaylight.netconf.api.NetconfSessionListener;
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.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
public abstract class AbstractNetconfSessionNegotiator,
L extends NetconfSessionListener>
extends ChannelInboundHandlerAdapter implements NetconfSessionNegotiator {
/**
* Possible states for Finite State Machine.
*/
protected enum State {
IDLE, OPEN_WAIT, FAILED, ESTABLISHED
}
private static final Logger LOG = LoggerFactory.getLogger(AbstractNetconfSessionNegotiator.class);
private static final String NAME_OF_EXCEPTION_HANDLER = "lastExceptionHandler";
private static final String DEFAULT_MAXIMUM_CHUNK_SIZE_PROP = "org.opendaylight.netconf.default.maximum.chunk.size";
private static final int DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT = 16 * 1024 * 1024;
/**
* Default upper bound on the size of an individual chunk. This value can be controlled through
* {@value #DEFAULT_MAXIMUM_CHUNK_SIZE_PROP} system property and defaults to
* {@value #DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT} bytes.
*/
@Beta
public static final @NonNegative int DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE;
static {
final int propValue = Integer.getInteger(DEFAULT_MAXIMUM_CHUNK_SIZE_PROP, DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT);
if (propValue <= 0) {
LOG.warn("Ignoring invalid {} value {}", DEFAULT_MAXIMUM_CHUNK_SIZE_PROP, propValue);
DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE = DEFAULT_MAXIMUM_CHUNK_SIZE_DEFAULT;
} else {
DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE = propValue;
}
LOG.debug("Default maximum incoming NETCONF chunk size is {} bytes", DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE);
}
private final @NonNull NetconfHelloMessage localHello;
protected final Channel channel;
private final @NonNegative int maximumIncomingChunkSize;
private final long connectionTimeoutMillis;
private final Promise promise;
private final L sessionListener;
private final Timer timer;
@GuardedBy("this")
private Timeout timeoutTask;
@GuardedBy("this")
private State state = State.IDLE;
protected AbstractNetconfSessionNegotiator(final NetconfHelloMessage hello, final Promise promise,
final Channel channel, final Timer timer, final L sessionListener,
final long connectionTimeoutMillis,
final @NonNegative int maximumIncomingChunkSize) {
this.localHello = requireNonNull(hello);
this.promise = requireNonNull(promise);
this.channel = requireNonNull(channel);
this.timer = timer;
this.sessionListener = sessionListener;
this.connectionTimeoutMillis = connectionTimeoutMillis;
this.maximumIncomingChunkSize = maximumIncomingChunkSize;
checkArgument(maximumIncomingChunkSize > 0, "Invalid maximum incoming chunk size %s", maximumIncomingChunkSize);
}
@Deprecated(since = "4.0.1", forRemoval = true)
protected AbstractNetconfSessionNegotiator(final NetconfHelloMessage hello, final Promise promise,
final Channel channel, final Timer timer,
final L sessionListener, final long connectionTimeoutMillis) {
this(hello, promise, channel, timer, sessionListener, connectionTimeoutMillis,
DEFAULT_MAXIMUM_INCOMING_CHUNK_SIZE);
}
protected final @NonNull NetconfHelloMessage localHello() {
return localHello;
}
protected final void startNegotiation() {
if (ifNegotiatedAlready()) {
LOG.debug("Negotiation on channel {} already started", channel);
} else {
final var sslHandler = getSslHandler(channel);
if (sslHandler != null) {
sslHandler.handshakeFuture().addListener(future -> {
checkState(future.isSuccess(), "Ssl handshake was not successful");
LOG.debug("Ssl handshake complete");
start();
});
} else {
start();
}
}
}
protected final synchronized boolean ifNegotiatedAlready() {
// Indicates whether negotiation already started
return this.state != State.IDLE;
}
private static @Nullable SslHandler getSslHandler(final Channel channel) {
return channel.pipeline().get(SslHandler.class);
}
private void start() {
LOG.debug("Session negotiation started with hello message {} on channel {}", localHello, channel);
channel.pipeline().addLast(NAME_OF_EXCEPTION_HANDLER, new ExceptionHandlingInboundChannelHandler());
sendMessage(localHello);
replaceHelloMessageOutboundHandler();
synchronized (this) {
lockedChangeState(State.OPEN_WAIT);
// Service the timeout on channel's eventloop, so that we do not get state transition problems
timeoutTask = timer.newTimeout(unused -> channel.eventLoop().execute(this::timeoutExpired),
connectionTimeoutMillis, TimeUnit.MILLISECONDS);
}
}
private synchronized void timeoutExpired() {
if (timeoutTask == null) {
// cancelTimeout() between expiry and execution on the loop
return;
}
timeoutTask = null;
if (state != State.ESTABLISHED) {
LOG.debug("Connection timeout after {}ms, session backed by channel {} is in state {}",
connectionTimeoutMillis, channel, 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 (!promise.isDone() && !promise.isCancelled()) {
LOG.warn("Netconf session backed by channel {} was not established after {}", channel,
connectionTimeoutMillis);
changeState(State.FAILED);
channel.close().addListener(future -> {
if (future.isSuccess()) {
LOG.debug("Channel {} closed: success", channel);
} else {
LOG.warn("Channel {} closed: fail", channel);
}
});
}
} else if (channel.isOpen()) {
channel.pipeline().remove(NAME_OF_EXCEPTION_HANDLER);
}
}
private synchronized void cancelTimeout() {
if (timeoutTask != null && !timeoutTask.cancel()) {
// Late-coming cancel: make sure
timeoutTask = null;
}
}
protected final S getSessionForHelloMessage(final NetconfHelloMessage netconfMessage)
throws NetconfDocumentedException {
final Document doc = netconfMessage.getDocument();
if (shouldUseChunkFraming(doc)) {
insertChunkFramingToPipeline();
}
changeState(State.ESTABLISHED);
return getSession(sessionListener, channel, netconfMessage);
}
protected abstract S getSession(L sessionListener, Channel channel, NetconfHelloMessage message)
throws NetconfDocumentedException;
/**
* 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(maximumIncomingChunkSize));
}
private boolean shouldUseChunkFraming(final Document doc) {
return containsBase11Capability(doc) && containsBase11Capability(localHello.getDocument());
}
/**
* Remove special inbound handler for hello message. Insert regular netconf xml message (en|de)coders.
*
*
* 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());
checkState(helloMessageHandler instanceof NetconfXMLToHelloMessageDecoder,
"Pipeline handlers misplaced on session: %s, pipeline: %s", session, channel.pipeline());
Iterable