bgp/rib-impl/src/main/java/org/opendaylight/protocol/bgp/rib/impl/BGPSessionImpl.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 package org.opendaylight.protocol.bgp.rib.impl;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.annotations.VisibleForTesting;
  13 import com.google.common.base.MoreObjects;
  14 import com.google.common.base.MoreObjects.ToStringHelper;
  15 import com.google.common.base.Preconditions;
  16 import com.google.common.collect.Lists;
  17 import com.google.common.collect.Sets;
  18 import io.netty.buffer.ByteBufUtil;
  19 import io.netty.channel.Channel;
  20 import io.netty.channel.ChannelFuture;
  21 import io.netty.channel.ChannelFutureListener;
  22 import io.netty.channel.ChannelHandlerContext;
  23 import io.netty.channel.ChannelPipeline;
  24 import io.netty.channel.SimpleChannelInboundHandler;
  25 import java.io.IOException;
  26 import java.nio.channels.NonWritableChannelException;
  27 import java.util.Collections;
  28 import java.util.Date;
  29 import java.util.List;
  30 import java.util.Set;
  31 import java.util.concurrent.TimeUnit;
  32 import javax.annotation.concurrent.GuardedBy;
  33 import org.opendaylight.protocol.bgp.parser.AsNumberUtil;
  34 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  35 import org.opendaylight.protocol.bgp.parser.BGPError;
  36 import org.opendaylight.protocol.bgp.parser.BgpExtendedMessageUtil;
  37 import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl;
  38 import org.opendaylight.protocol.bgp.parser.spi.MultiPathSupport;
  39 import org.opendaylight.protocol.bgp.parser.spi.pojo.MultiPathSupportImpl;
  40 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPMessagesListener;
  41 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
  42 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  43 import org.opendaylight.protocol.bgp.rib.impl.state.BGPSessionStateImpl;
  44 import org.opendaylight.protocol.bgp.rib.impl.state.BGPSessionStateProvider;
  45 import org.opendaylight.protocol.bgp.rib.spi.BGPSession;
  46 import org.opendaylight.protocol.bgp.rib.spi.BGPSessionListener;
  47 import org.opendaylight.protocol.bgp.rib.spi.BGPTerminationReason;
  48 import org.opendaylight.protocol.bgp.rib.spi.State;
  49 import org.opendaylight.protocol.bgp.rib.spi.state.BGPSessionState;
  50 import org.opendaylight.protocol.bgp.rib.spi.state.BGPTimersState;
  51 import org.opendaylight.protocol.bgp.rib.spi.state.BGPTransportState;
  52 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.AsNumber;
  53 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv4Address;
  54 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.Keepalive;
  55 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.KeepaliveBuilder;
  56 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.Notify;
  57 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.NotifyBuilder;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.Open;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.Update;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.open.message.BgpParameters;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.open.message.bgp.parameters.OptionalCapabilities;
  62 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.open.message.bgp.parameters.optional.capabilities.CParameters;
  63 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.BgpTableType;
  64 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.CParameters1;
  65 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.RouteRefresh;
  66 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.mp.capabilities.AddPathCapability;
  67 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.mp.capabilities.MultiprotocolCapability;
  68 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.mp.capabilities.add.path.capability.AddressFamilies;
  69 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.rib.TablesKey;
  70 import org.opendaylight.yangtools.yang.binding.Notification;
  71 import org.slf4j.Logger;
  72 import org.slf4j.LoggerFactory;
  73
  74 @VisibleForTesting
  75 public class BGPSessionImpl extends SimpleChannelInboundHandler<Notification> implements BGPSession,
  76         BGPSessionStateProvider, AutoCloseable {
  77
  78     private static final Logger LOG = LoggerFactory.getLogger(BGPSessionImpl.class);
  79
  80     private static final Notification KEEP_ALIVE = new KeepaliveBuilder().build();
  81
  82     private static final int KA_TO_DEADTIMER_RATIO = 3;
  83
  84     private static final String EXTENDED_MSG_DECODER = "EXTENDED_MSG_DECODER";
  85
  86     static final String END_OF_INPUT = "End of input detected. Close the session.";
  87
  88     /**
  89      * System.nanoTime value about when was sent the last message.
  90      */
  91     @VisibleForTesting
  92     private long lastMessageSentAt;
  93
  94     /**
  95      * System.nanoTime value about when was received the last message
  96      */
  97     private long lastMessageReceivedAt;
  98
  99     private final BGPSessionListener listener;
 100
 101     private final BGPSynchronization sync;
 102
 103     private int kaCounter = 0;
 104
 105     private final Channel channel;
 106
 107     @GuardedBy("this")
 108     private State state = State.OPEN_CONFIRM;
 109
 110     private final Set<BgpTableType> tableTypes;
 111     private final List<AddressFamilies> addPathTypes;
 112     private final int holdTimerValue;
 113     private final int keepAlive;
 114     private final AsNumber asNumber;
 115     private final Ipv4Address bgpId;
 116     private final BGPPeerRegistry peerRegistry;
 117     private final ChannelOutputLimiter limiter;
 118     private final BGPSessionStateImpl sessionState;
 119     private boolean terminationReasonNotified;
 120
 121     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen,
 122             final BGPSessionPreferences localPreferences, final BGPPeerRegistry peerRegistry) {
 123         this(listener, channel, remoteOpen, localPreferences.getHoldTime(), peerRegistry);
 124     }
 125
 126     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen,
 127             final int localHoldTimer, final BGPPeerRegistry peerRegistry) {
 128         this.listener = requireNonNull(listener);
 129         this.channel = requireNonNull(channel);
 130         this.limiter = new ChannelOutputLimiter(this);
 131         this.channel.pipeline().addLast(this.limiter);
 132         this.holdTimerValue = (remoteOpen.getHoldTimer() < localHoldTimer) ? remoteOpen.getHoldTimer() : localHoldTimer;
 133         LOG.info("BGP HoldTimer new value: {}", this.holdTimerValue);
 134         this.keepAlive = this.holdTimerValue / KA_TO_DEADTIMER_RATIO;
 135         this.asNumber = AsNumberUtil.advertizedAsNumber(remoteOpen);
 136         this.peerRegistry = peerRegistry;
 137         this.sessionState = new BGPSessionStateImpl();
 138
 139         final Set<TablesKey> tts = Sets.newHashSet();
 140         final Set<BgpTableType> tats = Sets.newHashSet();
 141         final List<AddressFamilies> addPathCapabilitiesList = Lists.newArrayList();
 142         if (remoteOpen.getBgpParameters() != null) {
 143             for (final BgpParameters param : remoteOpen.getBgpParameters()) {
 144                 for (final OptionalCapabilities optCapa : param.getOptionalCapabilities()) {
 145                     final CParameters cParam = optCapa.getCParameters();
 146                     if (cParam.getAugmentation(CParameters1.class) == null) {
 147                         continue;
 148                     }
 149                     if (cParam.getAugmentation(CParameters1.class).getMultiprotocolCapability() != null) {
 150                         final MultiprotocolCapability multi = cParam.getAugmentation(CParameters1.class).getMultiprotocolCapability();
 151                         final TablesKey tt = new TablesKey(multi.getAfi(), multi.getSafi());
 152                         LOG.trace("Added table type to sync {}", tt);
 153                         tts.add(tt);
 154                         tats.add(new BgpTableTypeImpl(tt.getAfi(), tt.getSafi()));
 155                     } else if (cParam.getAugmentation(CParameters1.class).getAddPathCapability() != null) {
 156                         final AddPathCapability addPathCap = cParam.getAugmentation(CParameters1.class).getAddPathCapability();
 157                         addPathCapabilitiesList.addAll(addPathCap.getAddressFamilies());
 158                     }
 159                 }
 160             }
 161         }
 162
 163         this.sync = new BGPSynchronization(this.listener, tts);
 164         this.tableTypes = tats;
 165         this.addPathTypes = addPathCapabilitiesList;
 166
 167         if (!this.addPathTypes.isEmpty()) {
 168             final ChannelPipeline pipeline = this.channel.pipeline();
 169             final BGPByteToMessageDecoder decoder = pipeline.get(BGPByteToMessageDecoder.class);
 170             decoder.addDecoderConstraint(MultiPathSupport.class,
 171                     MultiPathSupportImpl.createParserMultiPathSupport(this.addPathTypes));
 172         }
 173
 174         if (this.holdTimerValue != 0) {
 175             channel.eventLoop().schedule(this::handleHoldTimer, this.holdTimerValue, TimeUnit.SECONDS);
 176             channel.eventLoop().schedule(this::handleKeepaliveTimer, this.keepAlive, TimeUnit.SECONDS);
 177         }
 178         this.bgpId = remoteOpen.getBgpIdentifier();
 179         this.sessionState.advertizeCapabilities(this.holdTimerValue, channel.remoteAddress(), channel.localAddress(),
 180                 this.tableTypes, remoteOpen.getBgpParameters());
 181     }
 182
 183     /**
 184      * Set the extend message coder for current channel
 185      * The reason for separating this part from constructor is, in #channel.pipeline().replace(..), the
 186      * invokeChannelRead() will be invoked after the original message coder handler got removed. And there
 187      * is chance that before the session instance is fully initiated (constructor returns), a KeepAlive
 188      * message arrived already in the channel buffer. Thus #AbstractBGPSessionNegotiator.handleMessage(..)
 189      * gets invoked again and a deadlock is caused.  A BGP final state machine error will happen as BGP
 190      * negotiator is still in OPEN_SENT state as the session constructor hasn't returned yet.
 191      *
 192      * @param remoteOpen
 193      */
 194     public synchronized void setChannelExtMsgCoder(final Open remoteOpen) {
 195         final boolean enableExMess = BgpExtendedMessageUtil.advertizedBgpExtendedMessageCapability(remoteOpen);
 196         if (enableExMess) {
 197             this.channel.pipeline().replace(BGPMessageHeaderDecoder.class, EXTENDED_MSG_DECODER,
 198                     BGPMessageHeaderDecoder.getExtendedBGPMessageHeaderDecoder());
 199         }
 200     }
 201
 202     @Override
 203     public synchronized void close() {
 204         if (this.state != State.IDLE && !this.terminationReasonNotified) {
 205             this.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode())
 206                     .setErrorSubcode(BGPError.CEASE.getSubcode()).build());
 207             this.closeWithoutMessage();
 208         }
 209     }
 210
 211     /**
 212      * Handles incoming message based on their type.
 213      *
 214      * @param msg incoming message
 215      */
 216     synchronized void handleMessage(final Notification msg) {
 217         if (this.state == State.IDLE) {
 218             return;
 219         }
 220         try {
 221             // Update last reception time
 222             this.lastMessageReceivedAt = System.nanoTime();
 223
 224             if (msg instanceof Open) {
 225                 // Open messages should not be present here
 226                 this.terminate(new BGPDocumentedException(null, BGPError.FSM_ERROR));
 227             } else if (msg instanceof Notify) {
 228                 final Notify notify = (Notify) msg;
 229                 // Notifications are handled internally
 230                 LOG.info("Session closed because Notification message received: {} / {}, data={}",
 231                         notify.getErrorCode(),
 232                         notify.getErrorSubcode(),
 233                         notify.getData() != null ? ByteBufUtil.hexDump(notify.getData()) : null);
 234                 notifyTerminationReasonAndCloseWithoutMessage(notify.getErrorCode(), notify.getErrorSubcode());
 235             } else if (msg instanceof Keepalive) {
 236                 // Keepalives are handled internally
 237                 LOG.trace("Received KeepAlive message.");
 238                 this.kaCounter++;
 239                 if (this.kaCounter >= 2) {
 240                     this.sync.kaReceived();
 241                 }
 242             } else if (msg instanceof RouteRefresh) {
 243                 this.listener.onMessage(this, msg);
 244             } else if (msg instanceof Update) {
 245                 this.listener.onMessage(this, msg);
 246                 this.sync.updReceived((Update) msg);
 247             } else {
 248                 LOG.warn("Ignoring unhandled message: {}.", msg.getClass());
 249             }
 250
 251             this.sessionState.messageReceived(msg);
 252         } catch (final BGPDocumentedException e) {
 253             this.terminate(e);
 254         }
 255     }
 256
 257     private synchronized void notifyTerminationReasonAndCloseWithoutMessage(
 258             final Short errorCode,
 259             final Short errorSubcode) {
 260         this.terminationReasonNotified = true;
 261         this.listener.onSessionTerminated(this, new BGPTerminationReason(
 262                 BGPError.forValue(errorCode, errorSubcode)));
 263         this.closeWithoutMessage();
 264     }
 265
 266     synchronized void endOfInput() {
 267         if (this.state == State.UP) {
 268             LOG.info(END_OF_INPUT);
 269             this.listener.onSessionDown(this, new IOException(END_OF_INPUT));
 270         }
 271     }
 272
 273     @GuardedBy("this")
 274     private ChannelFuture writeEpilogue(final ChannelFuture future, final Notification msg) {
 275         future.addListener(
 276                 (ChannelFutureListener) f -> {
 277                     if (!f.isSuccess()) {
 278                         LOG.warn("Failed to send message {} to socket {}", msg, BGPSessionImpl.this.channel, f.cause());
 279                     } else {
 280                         LOG.trace("Message {} sent to socket {}", msg, BGPSessionImpl.this.channel);
 281                     }
 282                 });
 283         this.lastMessageSentAt = System.nanoTime();
 284         this.sessionState.messageSent(msg);
 285         return future;
 286     }
 287
 288     void flush() {
 289         this.channel.flush();
 290     }
 291
 292     synchronized void write(final Notification msg) {
 293         try {
 294             writeEpilogue(this.channel.write(msg), msg);
 295         } catch (final Exception e) {
 296             LOG.warn("Message {} was not sent.", msg, e);
 297         }
 298     }
 299
 300     synchronized ChannelFuture writeAndFlush(final Notification msg) {
 301         if (isWritable()) {
 302             return writeEpilogue(this.channel.writeAndFlush(msg), msg);
 303         }
 304         return this.channel.newFailedFuture(new NonWritableChannelException());
 305     }
 306
 307     private synchronized void closeWithoutMessage() {
 308         if (this.state == State.IDLE) {
 309             return;
 310         }
 311         LOG.info("Closing session: {}", this);
 312         this.channel.close().addListener((ChannelFutureListener) future -> Preconditions.checkArgument(future.isSuccess(), "Channel failed to close: %s", future.cause()));
 313         this.state = State.IDLE;
 314         removePeerSession();
 315         this.sessionState.setSessionState(this.state);
 316     }
 317
 318     /**
 319      * Closes BGP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 320      * modified, because he initiated the closing. (To prevent concurrent modification exception).
 321      *
 322      * @param e BGPDocumentedException
 323      */
 324     private synchronized void terminate(final BGPDocumentedException e) {
 325         final BGPError error = e.getError();
 326         final byte[] data = e.getData();
 327         final NotifyBuilder builder = new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode());
 328         if (data != null && data.length != 0) {
 329             builder.setData(data);
 330         }
 331         this.writeAndFlush(builder.build());
 332         notifyTerminationReasonAndCloseWithoutMessage(error.getCode(), error.getSubcode());
 333     }
 334
 335     private void removePeerSession() {
 336         if (this.peerRegistry != null) {
 337             this.peerRegistry.removePeerSession(StrictBGPPeerRegistry.getIpAddress(this.channel.remoteAddress()));
 338         }
 339     }
 340
 341     /**
 342      * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 343      * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 344      * which the message was received. If the session was closed by the time this method starts to execute (the session
 345      * state will become IDLE), then rescheduling won't occur.
 346      */
 347     private synchronized void handleHoldTimer() {
 348         if (this.state == State.IDLE) {
 349             return;
 350         }
 351
 352         final long ct = System.nanoTime();
 353         final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 354
 355         if (ct >= nextHold) {
 356             LOG.debug("HoldTimer expired. {}", new Date());
 357             this.terminate(new BGPDocumentedException(BGPError.HOLD_TIMER_EXPIRED));
 358         } else {
 359             this.channel.eventLoop().schedule(this::handleHoldTimer, nextHold - ct, TimeUnit.NANOSECONDS);
 360         }
 361     }
 362
 363     /**
 364      * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 365      * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 366      * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 367      * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 368      */
 369     private synchronized void handleKeepaliveTimer() {
 370         if (this.state == State.IDLE) {
 371             return;
 372         }
 373
 374         final long ct = System.nanoTime();
 375         long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 376
 377         if (ct >= nextKeepalive) {
 378             this.writeAndFlush(KEEP_ALIVE);
 379             nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 380         }
 381         this.channel.eventLoop().schedule(this::handleKeepaliveTimer, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 382     }
 383
 384     @Override
 385     public final String toString() {
 386         return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
 387     }
 388
 389     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 390         toStringHelper.add("channel", this.channel);
 391         toStringHelper.add("state", this.getState());
 392         return toStringHelper;
 393     }
 394
 395     @Override
 396     public Set<BgpTableType> getAdvertisedTableTypes() {
 397         return this.tableTypes;
 398     }
 399
 400     @Override
 401     public List<AddressFamilies> getAdvertisedAddPathTableTypes() {
 402         return this.addPathTypes;
 403     }
 404
 405     @Override
 406     public List<BgpTableType> getAdvertisedGracefulRestartTableTypes() {
 407         return Collections.emptyList();
 408     }
 409
 410     @VisibleForTesting
 411     synchronized void sessionUp() {
 412         this.state = State.UP;
 413         this.sessionState.setSessionState(this.state);
 414         this.listener.onSessionUp(this);
 415     }
 416
 417     public synchronized State getState() {
 418         return this.state;
 419     }
 420
 421     @Override
 422     public final Ipv4Address getBgpId() {
 423         return this.bgpId;
 424     }
 425
 426     @Override
 427     public final AsNumber getAsNumber() {
 428         return this.asNumber;
 429     }
 430
 431     private synchronized boolean isWritable() {
 432         return this.channel != null && this.channel.isWritable();
 433     }
 434
 435     public ChannelOutputLimiter getLimiter() {
 436         return this.limiter;
 437     }
 438
 439     @Override
 440     public final void channelInactive(final ChannelHandlerContext ctx) {
 441         LOG.debug("Channel {} inactive.", ctx.channel());
 442         this.endOfInput();
 443
 444         try {
 445             super.channelInactive(ctx);
 446         } catch (final Exception e) {
 447             throw new IllegalStateException("Failed to delegate channel inactive event on channel " + ctx.channel(), e);
 448         }
 449     }
 450
 451     @Override
 452     protected final void channelRead0(final ChannelHandlerContext ctx, final Notification msg) {
 453         LOG.debug("Message was received: {}", msg);
 454         this.handleMessage(msg);
 455     }
 456
 457     @Override
 458     public final void handlerAdded(final ChannelHandlerContext ctx) {
 459         this.sessionUp();
 460     }
 461
 462     @Override
 463     public synchronized void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
 464         LOG.warn("BGP session encountered error", cause);
 465         final Throwable docCause = cause.getCause();
 466         if (docCause instanceof BGPDocumentedException) {
 467             this.terminate((BGPDocumentedException) docCause);
 468         } else {
 469             this.close();
 470         }
 471     }
 472
 473     @Override
 474     public BGPSessionState getBGPSessionState() {
 475         return this.sessionState;
 476     }
 477
 478     @Override
 479     public BGPTimersState getBGPTimersState() {
 480         return this.sessionState;
 481     }
 482
 483     @Override
 484     public BGPTransportState getBGPTransportState() {
 485         return this.sessionState;
 486     }
 487
 488     @Override
 489     public void registerMessagesCounter(final BGPMessagesListener bgpMessagesListener) {
 490         this.sessionState.registerMessagesCounter(bgpMessagesListener);
 491     }
 492 }