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 io.netty.buffer.ByteBufUtil;
  17 import io.netty.channel.Channel;
  18 import io.netty.channel.ChannelFuture;
  19 import io.netty.channel.ChannelFutureListener;
  20 import io.netty.channel.ChannelHandlerContext;
  21 import io.netty.channel.ChannelPipeline;
  22 import io.netty.channel.SimpleChannelInboundHandler;
  23 import java.io.IOException;
  24 import java.nio.channels.NonWritableChannelException;
  25 import java.util.ArrayList;
  26 import java.util.Collections;
  27 import java.util.Date;
  28 import java.util.HashSet;
  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.rev180329.Keepalive;
  55 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.KeepaliveBuilder;
  56 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.Notify;
  57 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.NotifyBuilder;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.Open;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.Update;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.open.message.BgpParameters;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.open.message.bgp.parameters.OptionalCapabilities;
  62 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.open.message.bgp.parameters.optional.capabilities.CParameters;
  63 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.BgpTableType;
  64 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.CParameters1;
  65 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.RouteRefresh;
  66 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.mp.capabilities.AddPathCapability;
  67 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.mp.capabilities.MultiprotocolCapability;
  68 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.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 = new HashSet<>();
 140         final Set<BgpTableType> tats = new HashSet<>();
 141         final List<AddressFamilies> addPathCapabilitiesList = new ArrayList<>();
 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                     final CParameters1 cParam1 = cParam.augmentation(CParameters1.class);
 147                     if (cParam1 != null) {
 148                         final MultiprotocolCapability multi = cParam1.getMultiprotocolCapability();
 149                         if (multi != null) {
 150                             final TablesKey tt = new TablesKey(multi.getAfi(), multi.getSafi());
 151                             LOG.trace("Added table type to sync {}", tt);
 152                             tts.add(tt);
 153                             tats.add(new BgpTableTypeImpl(tt.getAfi(), tt.getSafi()));
 154                         } else {
 155                             final AddPathCapability addPathCap = cParam1.getAddPathCapability();
 156                             if (addPathCap != null) {
 157                                 addPathCapabilitiesList.addAll(addPathCap.getAddressFamilies());
 158                             }
 159                         }
 160                     }
 161                 }
 162             }
 163         }
 164
 165         this.sync = new BGPSynchronization(this.listener, tts);
 166         this.tableTypes = tats;
 167         this.addPathTypes = addPathCapabilitiesList;
 168
 169         if (!this.addPathTypes.isEmpty()) {
 170             final ChannelPipeline pipeline = this.channel.pipeline();
 171             final BGPByteToMessageDecoder decoder = pipeline.get(BGPByteToMessageDecoder.class);
 172             decoder.addDecoderConstraint(MultiPathSupport.class,
 173                     MultiPathSupportImpl.createParserMultiPathSupport(this.addPathTypes));
 174         }
 175
 176         if (this.holdTimerValue != 0) {
 177             channel.eventLoop().schedule(this::handleHoldTimer, this.holdTimerValue, TimeUnit.SECONDS);
 178             channel.eventLoop().schedule(this::handleKeepaliveTimer, this.keepAlive, TimeUnit.SECONDS);
 179         }
 180         this.bgpId = remoteOpen.getBgpIdentifier();
 181         this.sessionState.advertizeCapabilities(this.holdTimerValue, channel.remoteAddress(), channel.localAddress(),
 182                 this.tableTypes, remoteOpen.getBgpParameters());
 183     }
 184
 185     /**
 186      * Set the extend message coder for current channel
 187      * The reason for separating this part from constructor is, in #channel.pipeline().replace(..), the
 188      * invokeChannelRead() will be invoked after the original message coder handler got removed. And there
 189      * is chance that before the session instance is fully initiated (constructor returns), a KeepAlive
 190      * message arrived already in the channel buffer. Thus #AbstractBGPSessionNegotiator.handleMessage(..)
 191      * gets invoked again and a deadlock is caused.  A BGP final state machine error will happen as BGP
 192      * negotiator is still in OPEN_SENT state as the session constructor hasn't returned yet.
 193      *
 194      * @param remoteOpen
 195      */
 196     public synchronized void setChannelExtMsgCoder(final Open remoteOpen) {
 197         final boolean enableExMess = BgpExtendedMessageUtil.advertizedBgpExtendedMessageCapability(remoteOpen);
 198         if (enableExMess) {
 199             this.channel.pipeline().replace(BGPMessageHeaderDecoder.class, EXTENDED_MSG_DECODER,
 200                     BGPMessageHeaderDecoder.getExtendedBGPMessageHeaderDecoder());
 201         }
 202     }
 203
 204     @Override
 205     public synchronized void close() {
 206         if (this.state != State.IDLE) {
 207             if (!this.terminationReasonNotified) {
 208                 this.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode())
 209                         .setErrorSubcode(BGPError.CEASE.getSubcode()).build());
 210             }
 211             this.closeWithoutMessage();
 212         }
 213     }
 214
 215     /**
 216      * Handles incoming message based on their type.
 217      *
 218      * @param msg incoming message
 219      */
 220     synchronized void handleMessage(final Notification msg) {
 221         if (this.state == State.IDLE) {
 222             return;
 223         }
 224         try {
 225             // Update last reception time
 226             this.lastMessageReceivedAt = System.nanoTime();
 227
 228             if (msg instanceof Open) {
 229                 // Open messages should not be present here
 230                 this.terminate(new BGPDocumentedException(null, BGPError.FSM_ERROR));
 231             } else if (msg instanceof Notify) {
 232                 final Notify notify = (Notify) msg;
 233                 // Notifications are handled internally
 234                 LOG.info("Session closed because Notification message received: {} / {}, data={}",
 235                         notify.getErrorCode(),
 236                         notify.getErrorSubcode(),
 237                         notify.getData() != null ? ByteBufUtil.hexDump(notify.getData()) : null);
 238                 notifyTerminationReasonAndCloseWithoutMessage(notify.getErrorCode(), notify.getErrorSubcode());
 239             } else if (msg instanceof Keepalive) {
 240                 // Keepalives are handled internally
 241                 LOG.trace("Received KeepAlive message.");
 242                 this.kaCounter++;
 243                 if (this.kaCounter >= 2) {
 244                     this.sync.kaReceived();
 245                 }
 246             } else if (msg instanceof RouteRefresh) {
 247                 this.listener.onMessage(this, msg);
 248             } else if (msg instanceof Update) {
 249                 this.listener.onMessage(this, msg);
 250                 this.sync.updReceived((Update) msg);
 251             } else {
 252                 LOG.warn("Ignoring unhandled message: {}.", msg.getClass());
 253             }
 254
 255             this.sessionState.messageReceived(msg);
 256         } catch (final BGPDocumentedException e) {
 257             this.terminate(e);
 258         }
 259     }
 260
 261     private synchronized void notifyTerminationReasonAndCloseWithoutMessage(
 262             final Short errorCode,
 263             final Short errorSubcode) {
 264         this.terminationReasonNotified = true;
 265         this.closeWithoutMessage();
 266         this.listener.onSessionTerminated(this, new BGPTerminationReason(
 267                 BGPError.forValue(errorCode, errorSubcode)));
 268     }
 269
 270     synchronized void endOfInput() {
 271         if (this.state == State.UP) {
 272             LOG.info(END_OF_INPUT);
 273             this.listener.onSessionDown(this, new IOException(END_OF_INPUT));
 274         }
 275     }
 276
 277     @GuardedBy("this")
 278     private ChannelFuture writeEpilogue(final ChannelFuture future, final Notification msg) {
 279         future.addListener(
 280                 (ChannelFutureListener) f -> {
 281                     if (!f.isSuccess()) {
 282                         LOG.warn("Failed to send message {} to socket {}", msg, BGPSessionImpl.this.channel, f.cause());
 283                     } else {
 284                         LOG.trace("Message {} sent to socket {}", msg, BGPSessionImpl.this.channel);
 285                     }
 286                 });
 287         this.lastMessageSentAt = System.nanoTime();
 288         this.sessionState.messageSent(msg);
 289         return future;
 290     }
 291
 292     void flush() {
 293         this.channel.flush();
 294     }
 295
 296     synchronized void write(final Notification msg) {
 297         try {
 298             writeEpilogue(this.channel.write(msg), msg);
 299         } catch (final Exception e) {
 300             LOG.warn("Message {} was not sent.", msg, e);
 301         }
 302     }
 303
 304     synchronized ChannelFuture writeAndFlush(final Notification msg) {
 305         if (isWritable()) {
 306             return writeEpilogue(this.channel.writeAndFlush(msg), msg);
 307         }
 308         return this.channel.newFailedFuture(new NonWritableChannelException());
 309     }
 310
 311     @Override
 312     public synchronized void closeWithoutMessage() {
 313         if (this.state == State.IDLE) {
 314             return;
 315         }
 316         LOG.info("Closing session: {}", this);
 317         this.channel.close().addListener((ChannelFutureListener) future
 318                 -> Preconditions.checkArgument(future.isSuccess(),
 319                 "Channel failed to close: %s", future.cause()));
 320         this.state = State.IDLE;
 321         removePeerSession();
 322         this.sessionState.setSessionState(this.state);
 323     }
 324
 325     /**
 326      * Closes BGP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 327      * modified, because he initiated the closing. (To prevent concurrent modification exception).
 328      *
 329      * @param e BGPDocumentedException
 330      */
 331     @VisibleForTesting
 332     synchronized void terminate(final BGPDocumentedException e) {
 333         final BGPError error = e.getError();
 334         final byte[] data = e.getData();
 335         final NotifyBuilder builder = new NotifyBuilder().setErrorCode(error.getCode())
 336                 .setErrorSubcode(error.getSubcode());
 337         if (data != null && data.length != 0) {
 338             builder.setData(data);
 339         }
 340         this.writeAndFlush(builder.build());
 341         notifyTerminationReasonAndCloseWithoutMessage(error.getCode(), error.getSubcode());
 342     }
 343
 344     private void removePeerSession() {
 345         if (this.peerRegistry != null) {
 346             this.peerRegistry.removePeerSession(StrictBGPPeerRegistry.getIpAddress(this.channel.remoteAddress()));
 347         }
 348     }
 349
 350     /**
 351      * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 352      * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 353      * which the message was received. If the session was closed by the time this method starts to execute (the session
 354      * state will become IDLE), then rescheduling won't occur.
 355      */
 356     private synchronized void handleHoldTimer() {
 357         if (this.state == State.IDLE) {
 358             return;
 359         }
 360
 361         final long ct = System.nanoTime();
 362         final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 363
 364         if (ct >= nextHold) {
 365             LOG.debug("HoldTimer expired. {}", new Date());
 366             this.terminate(new BGPDocumentedException(BGPError.HOLD_TIMER_EXPIRED));
 367         } else {
 368             this.channel.eventLoop().schedule(this::handleHoldTimer, nextHold - ct, TimeUnit.NANOSECONDS);
 369         }
 370     }
 371
 372     /**
 373      * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 374      * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 375      * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 376      * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 377      */
 378     private synchronized void handleKeepaliveTimer() {
 379         if (this.state == State.IDLE) {
 380             return;
 381         }
 382
 383         final long ct = System.nanoTime();
 384         long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 385
 386         if (ct >= nextKeepalive) {
 387             this.writeAndFlush(KEEP_ALIVE);
 388             nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 389         }
 390         this.channel.eventLoop().schedule(this::handleKeepaliveTimer, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 391     }
 392
 393     @Override
 394     public final String toString() {
 395         return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
 396     }
 397
 398     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 399         toStringHelper.add("channel", this.channel);
 400         toStringHelper.add("state", this.getState());
 401         return toStringHelper;
 402     }
 403
 404     @Override
 405     public Set<BgpTableType> getAdvertisedTableTypes() {
 406         return this.tableTypes;
 407     }
 408
 409     @Override
 410     public List<AddressFamilies> getAdvertisedAddPathTableTypes() {
 411         return this.addPathTypes;
 412     }
 413
 414     @Override
 415     public List<BgpTableType> getAdvertisedGracefulRestartTableTypes() {
 416         return Collections.emptyList();
 417     }
 418
 419     @VisibleForTesting
 420     synchronized void sessionUp() {
 421         this.state = State.UP;
 422         try {
 423             this.sessionState.setSessionState(this.state);
 424             this.listener.onSessionUp(this);
 425         } catch (final Exception e) {
 426             handleException(e);
 427             throw e;
 428         }
 429     }
 430
 431     public synchronized State getState() {
 432         return this.state;
 433     }
 434
 435     @Override
 436     public final Ipv4Address getBgpId() {
 437         return this.bgpId;
 438     }
 439
 440     @Override
 441     public final AsNumber getAsNumber() {
 442         return this.asNumber;
 443     }
 444
 445     private synchronized boolean isWritable() {
 446         return this.channel != null && this.channel.isWritable();
 447     }
 448
 449     public ChannelOutputLimiter getLimiter() {
 450         return this.limiter;
 451     }
 452
 453     @Override
 454     public final void channelInactive(final ChannelHandlerContext ctx) {
 455         LOG.debug("Channel {} inactive.", ctx.channel());
 456         this.endOfInput();
 457
 458         try {
 459             super.channelInactive(ctx);
 460         } catch (final Exception e) {
 461             throw new IllegalStateException("Failed to delegate channel inactive event on channel " + ctx.channel(), e);
 462         }
 463     }
 464
 465     @Override
 466     protected final void channelRead0(final ChannelHandlerContext ctx, final Notification msg) {
 467         LOG.debug("Message was received: {}", msg);
 468         this.handleMessage(msg);
 469     }
 470
 471     @Override
 472     public final void handlerAdded(final ChannelHandlerContext ctx) {
 473         this.sessionUp();
 474     }
 475
 476     @Override
 477     public synchronized void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
 478         handleException(cause);
 479     }
 480
 481     /**
 482      * Handle exception occurred in the BGP session. The session in error state should be closed
 483      * properly so that it can be restored later.
 484      */
 485     @VisibleForTesting
 486     void handleException(final Throwable cause) {
 487         LOG.warn("BGP session encountered error", cause);
 488         final Throwable docCause = cause.getCause();
 489         if (docCause instanceof BGPDocumentedException) {
 490             this.terminate((BGPDocumentedException) docCause);
 491         } else {
 492             this.terminate(new BGPDocumentedException(BGPError.CEASE));
 493         }
 494     }
 495
 496     @Override
 497     public BGPSessionState getBGPSessionState() {
 498         return this.sessionState;
 499     }
 500
 501     @Override
 502     public BGPTimersState getBGPTimersState() {
 503         return this.sessionState;
 504     }
 505
 506     @Override
 507     public BGPTransportState getBGPTransportState() {
 508         return this.sessionState;
 509     }
 510
 511     @Override
 512     public void registerMessagesCounter(final BGPMessagesListener bgpMessagesListener) {
 513         this.sessionState.registerMessagesCounter(bgpMessagesListener);
 514     }
 515 }