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 com.google.common.annotations.VisibleForTesting;
  11 import com.google.common.base.MoreObjects;
  12 import com.google.common.base.MoreObjects.ToStringHelper;
  13 import com.google.common.base.Optional;
  14 import com.google.common.base.Preconditions;
  15 import com.google.common.collect.Lists;
  16 import com.google.common.collect.Sets;
  17 import io.netty.buffer.ByteBufUtil;
  18 import io.netty.channel.Channel;
  19 import io.netty.channel.ChannelFuture;
  20 import io.netty.channel.ChannelFutureListener;
  21 import io.netty.channel.ChannelHandlerContext;
  22 import io.netty.channel.ChannelPipeline;
  23 import io.netty.channel.SimpleChannelInboundHandler;
  24 import java.io.IOException;
  25 import java.nio.channels.NonWritableChannelException;
  26 import java.util.Date;
  27 import java.util.List;
  28 import java.util.Set;
  29 import java.util.concurrent.TimeUnit;
  30 import javax.annotation.concurrent.GuardedBy;
  31 import org.opendaylight.controller.config.yang.bgp.rib.impl.BgpSessionState;
  32 import org.opendaylight.protocol.bgp.parser.AsNumberUtil;
  33 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  34 import org.opendaylight.protocol.bgp.parser.BGPError;
  35 import org.opendaylight.protocol.bgp.parser.BgpExtendedMessageUtil;
  36 import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl;
  37 import org.opendaylight.protocol.bgp.parser.spi.MultiPathSupport;
  38 import org.opendaylight.protocol.bgp.parser.spi.pojo.MultiPathSupportImpl;
  39 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
  40 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  41 import org.opendaylight.protocol.bgp.rib.impl.stats.peer.BGPSessionStats;
  42 import org.opendaylight.protocol.bgp.rib.impl.stats.peer.BGPSessionStatsImpl;
  43 import org.opendaylight.protocol.bgp.rib.spi.BGPSession;
  44 import org.opendaylight.protocol.bgp.rib.spi.BGPSessionListener;
  45 import org.opendaylight.protocol.bgp.rib.spi.BGPTerminationReason;
  46 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.AsNumber;
  47 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv4Address;
  48 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Keepalive;
  49 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.KeepaliveBuilder;
  50 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Notify;
  51 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.NotifyBuilder;
  52 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Open;
  53 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Update;
  54 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.BgpParameters;
  55 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.OptionalCapabilities;
  56 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.optional.capabilities.CParameters;
  57 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.BgpTableType;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.CParameters1;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.RouteRefresh;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.AddPathCapability;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.MultiprotocolCapability;
  62 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.add.path.capability.AddressFamilies;
  63 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.TablesKey;
  64 import org.opendaylight.yangtools.yang.binding.Notification;
  65 import org.slf4j.Logger;
  66 import org.slf4j.LoggerFactory;
  67
  68 @VisibleForTesting
  69 public class BGPSessionImpl extends SimpleChannelInboundHandler<Notification> implements BGPSession, BGPSessionStats, AutoCloseable {
  70
  71     private static final Logger LOG = LoggerFactory.getLogger(BGPSessionImpl.class);
  72
  73     private static final Notification KEEP_ALIVE = new KeepaliveBuilder().build();
  74
  75     private static final int KA_TO_DEADTIMER_RATIO = 3;
  76
  77     private static final String EXTENDED_MSG_DECODER = "EXTENDED_MSG_DECODER";
  78
  79     static final String END_OF_INPUT = "End of input detected. Close the session.";
  80
  81     /**
  82      * Internal session state.
  83      */
  84     public enum State {
  85         /**
  86          * The session object is created by the negotiator in OpenConfirm state. While in this state, the session object
  87          * is half-alive, e.g. the timers are running, but the session is not completely up, e.g. it has not been
  88          * announced to the listener. If the session is torn down in this state, we do not inform the listener.
  89          */
  90         OPEN_CONFIRM,
  91         /**
  92          * The session has been completely established.
  93          */
  94         UP,
  95         /**
  96          * The session has been closed. It will not be resurrected.
  97          */
  98         IDLE,
  99     }
 100
 101     /**
 102      * System.nanoTime value about when was sent the last message.
 103      */
 104     @VisibleForTesting
 105     private long lastMessageSentAt;
 106
 107     /**
 108      * System.nanoTime value about when was received the last message
 109      */
 110     private long lastMessageReceivedAt;
 111
 112     private final BGPSessionListener listener;
 113
 114     private final BGPSynchronization sync;
 115
 116     private int kaCounter = 0;
 117
 118     private final Channel channel;
 119
 120     @GuardedBy("this")
 121     private State state = State.OPEN_CONFIRM;
 122
 123     private final Set<BgpTableType> tableTypes;
 124     private final List<AddressFamilies> addPathTypes;
 125     private final int holdTimerValue;
 126     private final int keepAlive;
 127     private final AsNumber asNumber;
 128     private final Ipv4Address bgpId;
 129     private final BGPPeerRegistry peerRegistry;
 130     private final ChannelOutputLimiter limiter;
 131
 132     private BGPSessionStatsImpl sessionStats;
 133
 134     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final BGPSessionPreferences localPreferences,
 135             final BGPPeerRegistry peerRegistry) {
 136         this(listener, channel, remoteOpen, localPreferences.getHoldTime(), peerRegistry);
 137         this.sessionStats = new BGPSessionStatsImpl(this, remoteOpen, this.holdTimerValue, this.keepAlive, channel, Optional.of(localPreferences), this.tableTypes, this.addPathTypes);
 138     }
 139
 140     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final int localHoldTimer,
 141             final BGPPeerRegistry peerRegistry) {
 142         this.listener = Preconditions.checkNotNull(listener);
 143         this.channel = Preconditions.checkNotNull(channel);
 144         this.limiter = new ChannelOutputLimiter(this);
 145         this.channel.pipeline().addLast(this.limiter);
 146         this.holdTimerValue = (remoteOpen.getHoldTimer() < localHoldTimer) ? remoteOpen.getHoldTimer() : localHoldTimer;
 147         LOG.info("BGP HoldTimer new value: {}", this.holdTimerValue);
 148         this.keepAlive = this.holdTimerValue / KA_TO_DEADTIMER_RATIO;
 149         this.asNumber = AsNumberUtil.advertizedAsNumber(remoteOpen);
 150         this.peerRegistry = peerRegistry;
 151
 152         final Set<TablesKey> tts = Sets.newHashSet();
 153         final Set<BgpTableType> tats = Sets.newHashSet();
 154         final List<AddressFamilies> addPathCapabilitiesList = Lists.newArrayList();
 155         if (remoteOpen.getBgpParameters() != null) {
 156             for (final BgpParameters param : remoteOpen.getBgpParameters()) {
 157                 for (final OptionalCapabilities optCapa : param.getOptionalCapabilities()) {
 158                     final CParameters cParam = optCapa.getCParameters();
 159                     if ( cParam.getAugmentation(CParameters1.class) == null) {
 160                         continue;
 161                     }
 162                     if(cParam.getAugmentation(CParameters1.class).getMultiprotocolCapability() != null) {
 163                         final MultiprotocolCapability multi = cParam.getAugmentation(CParameters1.class).getMultiprotocolCapability();
 164                         final TablesKey tt = new TablesKey(multi.getAfi(), multi.getSafi());
 165                         LOG.trace("Added table type to sync {}", tt);
 166                         tts.add(tt);
 167                         tats.add(new BgpTableTypeImpl(tt.getAfi(), tt.getSafi()));
 168                     } else if (cParam.getAugmentation(CParameters1.class).getAddPathCapability() != null) {
 169                         final AddPathCapability addPathCap = cParam.getAugmentation(CParameters1.class).getAddPathCapability();
 170                         addPathCapabilitiesList.addAll(addPathCap.getAddressFamilies());
 171                     }
 172                 }
 173             }
 174         }
 175
 176         this.sync = new BGPSynchronization(this.listener, tts);
 177         this.tableTypes = tats;
 178         this.addPathTypes = addPathCapabilitiesList;
 179
 180         if (! this.addPathTypes.isEmpty()) {
 181             final ChannelPipeline pipeline = this.channel.pipeline();
 182             final BGPByteToMessageDecoder decoder = pipeline.get(BGPByteToMessageDecoder.class);
 183             decoder.addDecoderConstraint(MultiPathSupport.class,
 184                     MultiPathSupportImpl.createParserMultiPathSupport(this.addPathTypes));
 185         }
 186
 187         if (this.holdTimerValue != 0) {
 188             channel.eventLoop().schedule(new Runnable() {
 189                 @Override
 190                 public void run() {
 191                     handleHoldTimer();
 192                 }
 193             }, this.holdTimerValue, TimeUnit.SECONDS);
 194
 195             channel.eventLoop().schedule(new Runnable() {
 196                 @Override
 197                 public void run() {
 198                     handleKeepaliveTimer();
 199                 }
 200             }, this.keepAlive, TimeUnit.SECONDS);
 201         }
 202         this.bgpId = remoteOpen.getBgpIdentifier();
 203         this.sessionStats = new BGPSessionStatsImpl(this, remoteOpen, this.holdTimerValue, this.keepAlive, channel, Optional.<BGPSessionPreferences>absent(),
 204                 this.tableTypes, this.addPathTypes);
 205     }
 206
 207     /**
 208      * Set the extend message coder for current channel
 209      * The reason for separating this part from constructor is, in #channel.pipeline().replace(..), the
 210      * invokeChannelRead() will be invoked after the original message coder handler got removed. And there
 211      * is chance that before the session instance is fully initiated (constructor returns), a KeepAlive
 212      * message arrived already in the channel buffer. Thus #AbstractBGPSessionNegotiator.handleMessage(..)
 213      * gets invoked again and a deadlock is caused.  A BGP final state machine error will happen as BGP
 214      * negotiator is still in OPEN_SENT state as the session constructor hasn't returned yet.
 215      *
 216      * @param remoteOpen
 217      */
 218     public synchronized void setChannelExtMsgCoder(final Open remoteOpen) {
 219         final boolean enableExMess = BgpExtendedMessageUtil.advertizedBgpExtendedMessageCapability(remoteOpen);
 220         if (enableExMess) {
 221             this.channel.pipeline().replace(BGPMessageHeaderDecoder.class, EXTENDED_MSG_DECODER, BGPMessageHeaderDecoder.getExtendedBGPMessageHeaderDecoder());
 222         }
 223     }
 224
 225     @Override
 226     public synchronized void close() {
 227         if (this.state != State.IDLE) {
 228             this.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode()).setErrorSubcode(BGPError.CEASE.getSubcode()).build());
 229         }
 230         this.closeWithoutMessage();
 231     }
 232
 233     /**
 234      * Handles incoming message based on their type.
 235      *
 236      * @param msg incoming message
 237      */
 238     synchronized void handleMessage(final Notification msg) throws BGPDocumentedException {
 239         // Update last reception time
 240         this.lastMessageReceivedAt = System.nanoTime();
 241
 242         if (msg instanceof Open) {
 243             // Open messages should not be present here
 244             this.terminate(new BGPDocumentedException(null, BGPError.FSM_ERROR));
 245         } else if (msg instanceof Notify) {
 246             final Notify notify = (Notify) msg;
 247             // Notifications are handled internally
 248             LOG.info("Session closed because Notification message received: {} / {}, data={}", notify.getErrorCode(),
 249                     notify.getErrorSubcode(), notify.getData() != null ? ByteBufUtil.hexDump(notify.getData()) : null);
 250             this.closeWithoutMessage();
 251             this.listener.onSessionTerminated(this, new BGPTerminationReason(
 252                     BGPError.forValue(notify.getErrorCode(), notify.getErrorSubcode())));
 253         } else if (msg instanceof Keepalive) {
 254             // Keepalives are handled internally
 255             LOG.trace("Received KeepAlive message.");
 256             this.kaCounter++;
 257             if (this.kaCounter >= 2) {
 258                 this.sync.kaReceived();
 259             }
 260         } else if (msg instanceof RouteRefresh) {
 261             this.listener.onMessage(this, msg);
 262         } else if (msg instanceof Update) {
 263             this.listener.onMessage(this, msg);
 264             this.sync.updReceived((Update) msg);
 265         } else {
 266             LOG.warn("Ignoring unhandled message: {}.", msg.getClass());
 267         }
 268
 269         this.sessionStats.updateReceivedMsg(msg);
 270     }
 271
 272     synchronized void endOfInput() {
 273         if (this.state == State.UP) {
 274             LOG.info(END_OF_INPUT);
 275             this.listener.onSessionDown(this, new IOException(END_OF_INPUT));
 276         }
 277     }
 278
 279     @GuardedBy("this")
 280     private ChannelFuture writeEpilogue(final ChannelFuture future, final Notification msg) {
 281         future.addListener(
 282             new ChannelFutureListener() {
 283                 @Override
 284                 public void operationComplete(final ChannelFuture f) {
 285                     if (!f.isSuccess()) {
 286                         LOG.warn("Failed to send message {} to socket {}", msg, BGPSessionImpl.this.channel, f.cause());
 287                     } else {
 288                         LOG.trace("Message {} sent to socket {}", msg, BGPSessionImpl.this.channel);
 289                     }
 290                 }
 291             });
 292         this.lastMessageSentAt = System.nanoTime();
 293         this.sessionStats.updateSentMsg(msg);
 294         return future;
 295     }
 296
 297     void flush() {
 298         this.channel.flush();
 299     }
 300
 301     synchronized void write(final Notification msg) {
 302         try {
 303             writeEpilogue(this.channel.write(msg), msg);
 304         } catch (final Exception e) {
 305             LOG.warn("Message {} was not sent.", msg, e);
 306         }
 307     }
 308
 309     synchronized ChannelFuture writeAndFlush(final Notification msg) {
 310         if (isWritable()) {
 311             return writeEpilogue(this.channel.writeAndFlush(msg), msg);
 312         }
 313         return this.channel.newFailedFuture(new NonWritableChannelException());
 314     }
 315
 316     private synchronized void closeWithoutMessage() {
 317         LOG.info("Closing session: {}", this);
 318         removePeerSession();
 319         this.channel.close().addListener(new ChannelFutureListener() {
 320             @Override
 321             public void operationComplete(final ChannelFuture future) throws Exception {
 322                 Preconditions.checkArgument(future.isSuccess(), "Channel failed to close: %s", future.cause());
 323             }
 324         });
 325         this.state = State.IDLE;
 326     }
 327
 328     /**
 329      * Closes BGP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 330      * modified, because he initiated the closing. (To prevent concurrent modification exception).
 331      *
 332      * @param e BGPDocumentedException
 333      */
 334     private synchronized void terminate(final BGPDocumentedException e) {
 335         final BGPError error = e.getError();
 336         final byte[] data = e.getData();
 337         final NotifyBuilder builder = new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode());
 338         if (data != null && data.length != 0) {
 339             builder.setData(data);
 340         }
 341         this.writeAndFlush(builder.build());
 342         this.closeWithoutMessage();
 343
 344         this.listener.onSessionTerminated(this, new BGPTerminationReason(error));
 345     }
 346
 347     private void removePeerSession() {
 348         if (this.peerRegistry != null) {
 349             this.peerRegistry.removePeerSession(StrictBGPPeerRegistry.getIpAddress(this.channel.remoteAddress()));
 350         }
 351     }
 352
 353     /**
 354      * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 355      * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 356      * which the message was received. If the session was closed by the time this method starts to execute (the session
 357      * state will become IDLE), then rescheduling won't occur.
 358      */
 359     private synchronized void handleHoldTimer() {
 360         if (this.state == State.IDLE) {
 361             return;
 362         }
 363
 364         final long ct = System.nanoTime();
 365         final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 366
 367         if (ct >= nextHold) {
 368             LOG.debug("HoldTimer expired. {}", new Date());
 369             this.terminate(new BGPDocumentedException(BGPError.HOLD_TIMER_EXPIRED));
 370         } else {
 371             this.channel.eventLoop().schedule(new Runnable() {
 372                 @Override
 373                 public void run() {
 374                     handleHoldTimer();
 375                 }
 376             }, nextHold - ct, TimeUnit.NANOSECONDS);
 377         }
 378     }
 379
 380     /**
 381      * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 382      * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 383      * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 384      * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 385      */
 386     private synchronized void handleKeepaliveTimer() {
 387         if (this.state == State.IDLE) {
 388             return;
 389         }
 390
 391         final long ct = System.nanoTime();
 392         long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 393
 394         if (ct >= nextKeepalive) {
 395             this.writeAndFlush(KEEP_ALIVE);
 396             nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 397             this.sessionStats.updateSentMsgKA();
 398         }
 399         this.channel.eventLoop().schedule(new Runnable() {
 400             @Override
 401             public void run() {
 402                 handleKeepaliveTimer();
 403             }
 404         }, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 405     }
 406
 407     @Override
 408     public final String toString() {
 409         return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
 410     }
 411
 412     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 413         toStringHelper.add("channel", this.channel);
 414         toStringHelper.add("state", this.getState());
 415         return toStringHelper;
 416     }
 417
 418     @Override
 419     public Set<BgpTableType> getAdvertisedTableTypes() {
 420         return this.tableTypes;
 421     }
 422
 423     @Override
 424     public List<AddressFamilies> getAdvertisedAddPathTableTypes() {
 425         return this.addPathTypes;
 426     }
 427
 428     protected synchronized void sessionUp() {
 429         this.sessionStats.startSessionStopwatch();
 430         this.state = State.UP;
 431         this.listener.onSessionUp(this);
 432     }
 433
 434     public synchronized State getState() {
 435         return this.state;
 436     }
 437
 438     @Override
 439     public final Ipv4Address getBgpId() {
 440         return this.bgpId;
 441     }
 442
 443     @Override
 444     public final AsNumber getAsNumber() {
 445         return this.asNumber;
 446     }
 447
 448     synchronized boolean isWritable() {
 449         return this.channel != null && this.channel.isWritable();
 450     }
 451
 452     void schedule(final Runnable task) {
 453         Preconditions.checkState(this.channel != null);
 454         this.channel.eventLoop().submit(task);
 455     }
 456
 457     @VisibleForTesting
 458     protected synchronized void setLastMessageSentAt(final long lastMessageSentAt) {
 459         this.lastMessageSentAt = lastMessageSentAt;
 460     }
 461
 462     @Override
 463     public synchronized BgpSessionState getBgpSessionState() {
 464         return this.sessionStats.getBgpSessionState();
 465     }
 466
 467     @Override
 468     public synchronized void resetBgpSessionStats() {
 469         this.sessionStats.resetBgpSessionStats();
 470     }
 471
 472     public ChannelOutputLimiter getLimiter() {
 473         return this.limiter;
 474     }
 475
 476     @Override
 477     public final void channelInactive(final ChannelHandlerContext ctx) {
 478         LOG.debug("Channel {} inactive.", ctx.channel());
 479         this.endOfInput();
 480
 481         try {
 482             super.channelInactive(ctx);
 483         } catch (final Exception e) {
 484             throw new IllegalStateException("Failed to delegate channel inactive event on channel " + ctx.channel(), e);
 485         }
 486     }
 487
 488     @Override
 489     protected final void channelRead0(final ChannelHandlerContext ctx, final Notification msg) {
 490         LOG.debug("Message was received: {}", msg);
 491         try {
 492             this.handleMessage(msg);
 493         } catch (final BGPDocumentedException e) {
 494             this.terminate(e);
 495         }
 496     }
 497
 498     @Override
 499     public final void handlerAdded(final ChannelHandlerContext ctx) {
 500         this.sessionUp();
 501     }
 502
 503     @Override
 504     public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
 505         LOG.warn("BGP session encountered error", cause);
 506         if (cause.getCause() instanceof BGPDocumentedException) {
 507             this.terminate((BGPDocumentedException) cause.getCause());
 508         } else {
 509             this.close();
 510         }
 511     }
 512 }