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.rev180329.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) {
 205             if (!this.terminationReasonNotified) {
 206                 this.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode())
 207                         .setErrorSubcode(BGPError.CEASE.getSubcode()).build());
 208             }
 209             this.closeWithoutMessage();
 210         }
 211     }
 212
 213     /**
 214      * Handles incoming message based on their type.
 215      *
 216      * @param msg incoming message
 217      */
 218     synchronized void handleMessage(final Notification msg) {
 219         if (this.state == State.IDLE) {
 220             return;
 221         }
 222         try {
 223             // Update last reception time
 224             this.lastMessageReceivedAt = System.nanoTime();
 225
 226             if (msg instanceof Open) {
 227                 // Open messages should not be present here
 228                 this.terminate(new BGPDocumentedException(null, BGPError.FSM_ERROR));
 229             } else if (msg instanceof Notify) {
 230                 final Notify notify = (Notify) msg;
 231                 // Notifications are handled internally
 232                 LOG.info("Session closed because Notification message received: {} / {}, data={}",
 233                         notify.getErrorCode(),
 234                         notify.getErrorSubcode(),
 235                         notify.getData() != null ? ByteBufUtil.hexDump(notify.getData()) : null);
 236                 notifyTerminationReasonAndCloseWithoutMessage(notify.getErrorCode(), notify.getErrorSubcode());
 237             } else if (msg instanceof Keepalive) {
 238                 // Keepalives are handled internally
 239                 LOG.trace("Received KeepAlive message.");
 240                 this.kaCounter++;
 241                 if (this.kaCounter >= 2) {
 242                     this.sync.kaReceived();
 243                 }
 244             } else if (msg instanceof RouteRefresh) {
 245                 this.listener.onMessage(this, msg);
 246             } else if (msg instanceof Update) {
 247                 this.listener.onMessage(this, msg);
 248                 this.sync.updReceived((Update) msg);
 249             } else {
 250                 LOG.warn("Ignoring unhandled message: {}.", msg.getClass());
 251             }
 252
 253             this.sessionState.messageReceived(msg);
 254         } catch (final BGPDocumentedException e) {
 255             this.terminate(e);
 256         }
 257     }
 258
 259     private synchronized void notifyTerminationReasonAndCloseWithoutMessage(
 260             final Short errorCode,
 261             final Short errorSubcode) {
 262         this.terminationReasonNotified = true;
 263         this.closeWithoutMessage();
 264         this.listener.onSessionTerminated(this, new BGPTerminationReason(
 265                 BGPError.forValue(errorCode, errorSubcode)));
 266     }
 267
 268     synchronized void endOfInput() {
 269         if (this.state == State.UP) {
 270             LOG.info(END_OF_INPUT);
 271             this.listener.onSessionDown(this, new IOException(END_OF_INPUT));
 272         }
 273     }
 274
 275     @GuardedBy("this")
 276     private ChannelFuture writeEpilogue(final ChannelFuture future, final Notification msg) {
 277         future.addListener(
 278                 (ChannelFutureListener) f -> {
 279                     if (!f.isSuccess()) {
 280                         LOG.warn("Failed to send message {} to socket {}", msg, BGPSessionImpl.this.channel, f.cause());
 281                     } else {
 282                         LOG.trace("Message {} sent to socket {}", msg, BGPSessionImpl.this.channel);
 283                     }
 284                 });
 285         this.lastMessageSentAt = System.nanoTime();
 286         this.sessionState.messageSent(msg);
 287         return future;
 288     }
 289
 290     void flush() {
 291         this.channel.flush();
 292     }
 293
 294     synchronized void write(final Notification msg) {
 295         try {
 296             writeEpilogue(this.channel.write(msg), msg);
 297         } catch (final Exception e) {
 298             LOG.warn("Message {} was not sent.", msg, e);
 299         }
 300     }
 301
 302     synchronized ChannelFuture writeAndFlush(final Notification msg) {
 303         if (isWritable()) {
 304             return writeEpilogue(this.channel.writeAndFlush(msg), msg);
 305         }
 306         return this.channel.newFailedFuture(new NonWritableChannelException());
 307     }
 308
 309     private synchronized void closeWithoutMessage() {
 310         if (this.state == State.IDLE) {
 311             return;
 312         }
 313         LOG.info("Closing session: {}", this);
 314         this.channel.close().addListener((ChannelFutureListener) future -> Preconditions.checkArgument(future.isSuccess(), "Channel failed to close: %s", future.cause()));
 315         this.state = State.IDLE;
 316         removePeerSession();
 317         this.sessionState.setSessionState(this.state);
 318     }
 319
 320     /**
 321      * Closes BGP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 322      * modified, because he initiated the closing. (To prevent concurrent modification exception).
 323      *
 324      * @param e BGPDocumentedException
 325      */
 326     @VisibleForTesting
 327     synchronized void terminate(final BGPDocumentedException e) {
 328         final BGPError error = e.getError();
 329         final byte[] data = e.getData();
 330         final NotifyBuilder builder = new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode());
 331         if (data != null && data.length != 0) {
 332             builder.setData(data);
 333         }
 334         this.writeAndFlush(builder.build());
 335         notifyTerminationReasonAndCloseWithoutMessage(error.getCode(), error.getSubcode());
 336     }
 337
 338     private void removePeerSession() {
 339         if (this.peerRegistry != null) {
 340             this.peerRegistry.removePeerSession(StrictBGPPeerRegistry.getIpAddress(this.channel.remoteAddress()));
 341         }
 342     }
 343
 344     /**
 345      * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 346      * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 347      * which the message was received. If the session was closed by the time this method starts to execute (the session
 348      * state will become IDLE), then rescheduling won't occur.
 349      */
 350     private synchronized void handleHoldTimer() {
 351         if (this.state == State.IDLE) {
 352             return;
 353         }
 354
 355         final long ct = System.nanoTime();
 356         final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 357
 358         if (ct >= nextHold) {
 359             LOG.debug("HoldTimer expired. {}", new Date());
 360             this.terminate(new BGPDocumentedException(BGPError.HOLD_TIMER_EXPIRED));
 361         } else {
 362             this.channel.eventLoop().schedule(this::handleHoldTimer, nextHold - ct, TimeUnit.NANOSECONDS);
 363         }
 364     }
 365
 366     /**
 367      * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 368      * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 369      * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 370      * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 371      */
 372     private synchronized void handleKeepaliveTimer() {
 373         if (this.state == State.IDLE) {
 374             return;
 375         }
 376
 377         final long ct = System.nanoTime();
 378         long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 379
 380         if (ct >= nextKeepalive) {
 381             this.writeAndFlush(KEEP_ALIVE);
 382             nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 383         }
 384         this.channel.eventLoop().schedule(this::handleKeepaliveTimer, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 385     }
 386
 387     @Override
 388     public final String toString() {
 389         return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
 390     }
 391
 392     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 393         toStringHelper.add("channel", this.channel);
 394         toStringHelper.add("state", this.getState());
 395         return toStringHelper;
 396     }
 397
 398     @Override
 399     public Set<BgpTableType> getAdvertisedTableTypes() {
 400         return this.tableTypes;
 401     }
 402
 403     @Override
 404     public List<AddressFamilies> getAdvertisedAddPathTableTypes() {
 405         return this.addPathTypes;
 406     }
 407
 408     @Override
 409     public List<BgpTableType> getAdvertisedGracefulRestartTableTypes() {
 410         return Collections.emptyList();
 411     }
 412
 413     @VisibleForTesting
 414     synchronized void sessionUp() {
 415         this.state = State.UP;
 416         try {
 417             this.sessionState.setSessionState(this.state);
 418             this.listener.onSessionUp(this);
 419         } catch (final Exception e) {
 420             handleException(e);
 421             throw e;
 422         }
 423     }
 424
 425     public synchronized State getState() {
 426         return this.state;
 427     }
 428
 429     @Override
 430     public final Ipv4Address getBgpId() {
 431         return this.bgpId;
 432     }
 433
 434     @Override
 435     public final AsNumber getAsNumber() {
 436         return this.asNumber;
 437     }
 438
 439     private synchronized boolean isWritable() {
 440         return this.channel != null && this.channel.isWritable();
 441     }
 442
 443     public ChannelOutputLimiter getLimiter() {
 444         return this.limiter;
 445     }
 446
 447     @Override
 448     public final void channelInactive(final ChannelHandlerContext ctx) {
 449         LOG.debug("Channel {} inactive.", ctx.channel());
 450         this.endOfInput();
 451
 452         try {
 453             super.channelInactive(ctx);
 454         } catch (final Exception e) {
 455             throw new IllegalStateException("Failed to delegate channel inactive event on channel " + ctx.channel(), e);
 456         }
 457     }
 458
 459     @Override
 460     protected final void channelRead0(final ChannelHandlerContext ctx, final Notification msg) {
 461         LOG.debug("Message was received: {}", msg);
 462         this.handleMessage(msg);
 463     }
 464
 465     @Override
 466     public final void handlerAdded(final ChannelHandlerContext ctx) {
 467         this.sessionUp();
 468     }
 469
 470     @Override
 471     public synchronized void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
 472         handleException(cause);
 473     }
 474
 475     /**
 476      * Handle exception occurred in the BGP session. The session in error state should be closed
 477      * properly so that it can be restored later.
 478      */
 479     @VisibleForTesting
 480     void handleException(final Throwable cause) {
 481         LOG.warn("BGP session encountered error", cause);
 482         final Throwable docCause = cause.getCause();
 483         if (docCause instanceof BGPDocumentedException) {
 484             this.terminate((BGPDocumentedException) docCause);
 485         } else {
 486             this.terminate(new BGPDocumentedException(BGPError.CEASE));
 487         }
 488     }
 489
 490     @Override
 491     public BGPSessionState getBGPSessionState() {
 492         return this.sessionState;
 493     }
 494
 495     @Override
 496     public BGPTimersState getBGPTimersState() {
 497         return this.sessionState;
 498     }
 499
 500     @Override
 501     public BGPTransportState getBGPTransportState() {
 502         return this.sessionState;
 503     }
 504
 505     @Override
 506     public void registerMessagesCounter(final BGPMessagesListener bgpMessagesListener) {
 507         this.sessionState.registerMessagesCounter(bgpMessagesListener);
 508     }
 509 }