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.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.util.Date;
  25 import java.util.List;
  26 import java.util.Set;
  27 import java.util.concurrent.TimeUnit;
  28 import javax.annotation.concurrent.GuardedBy;
  29 import org.opendaylight.controller.config.yang.bgp.rib.impl.BgpSessionState;
  30 import org.opendaylight.protocol.bgp.parser.AsNumberUtil;
  31 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  32 import org.opendaylight.protocol.bgp.parser.BGPError;
  33 import org.opendaylight.protocol.bgp.parser.BgpExtendedMessageUtil;
  34 import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl;
  35 import org.opendaylight.protocol.bgp.parser.spi.MultiPathSupport;
  36 import org.opendaylight.protocol.bgp.parser.spi.pojo.MultiPathSupportImpl;
  37 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
  38 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  39 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionStatistics;
  40 import org.opendaylight.protocol.bgp.rib.spi.BGPSession;
  41 import org.opendaylight.protocol.bgp.rib.spi.BGPSessionListener;
  42 import org.opendaylight.protocol.bgp.rib.spi.BGPTerminationReason;
  43 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.AsNumber;
  44 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
  45 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Keepalive;
  46 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.KeepaliveBuilder;
  47 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Notify;
  48 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.NotifyBuilder;
  49 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Open;
  50 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Update;
  51 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.BgpParameters;
  52 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.OptionalCapabilities;
  53 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.optional.capabilities.CParameters;
  54 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.BgpTableType;
  55 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.CParameters1;
  56 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.RouteRefresh;
  57 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.AddPathCapability;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.MultiprotocolCapability;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.add.path.capability.AddressFamilies;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.TablesKey;
  61 import org.opendaylight.yangtools.yang.binding.Notification;
  62 import org.slf4j.Logger;
  63 import org.slf4j.LoggerFactory;
  64
  65 @VisibleForTesting
  66 public class BGPSessionImpl extends SimpleChannelInboundHandler<Notification> implements BGPSession, BGPSessionStatistics, AutoCloseable {
  67
  68     private static final Logger LOG = LoggerFactory.getLogger(BGPSessionImpl.class);
  69
  70     private static final Notification KEEP_ALIVE = new KeepaliveBuilder().build();
  71
  72     private static final int KA_TO_DEADTIMER_RATIO = 3;
  73
  74     private static final String EXTENDED_MSG_DECODER = "EXTENDED_MSG_DECODER";
  75
  76     static final String END_OF_INPUT = "End of input detected. Close the session.";
  77
  78     /**
  79      * Internal session state.
  80      */
  81     public enum State {
  82         /**
  83          * The session object is created by the negotiator in OpenConfirm state. While in this state, the session object
  84          * is half-alive, e.g. the timers are running, but the session is not completely up, e.g. it has not been
  85          * announced to the listener. If the session is torn down in this state, we do not inform the listener.
  86          */
  87         OPEN_CONFIRM,
  88         /**
  89          * The session has been completely established.
  90          */
  91         UP,
  92         /**
  93          * The session has been closed. It will not be resurrected.
  94          */
  95         IDLE,
  96     }
  97
  98     /**
  99      * System.nanoTime value about when was sent the last message.
 100      */
 101     @VisibleForTesting
 102     private long lastMessageSentAt;
 103
 104     /**
 105      * System.nanoTime value about when was received the last message
 106      */
 107     private long lastMessageReceivedAt;
 108
 109     private final BGPSessionListener listener;
 110
 111     private final BGPSynchronization sync;
 112
 113     private int kaCounter = 0;
 114
 115     private final Channel channel;
 116
 117     @GuardedBy("this")
 118     private State state = State.OPEN_CONFIRM;
 119
 120     private final Set<BgpTableType> tableTypes;
 121     private final List<AddressFamilies> addPathTypes;
 122     private final int holdTimerValue;
 123     private final int keepAlive;
 124     private final AsNumber asNumber;
 125     private final Ipv4Address bgpId;
 126     private final BGPPeerRegistry peerRegistry;
 127     private final ChannelOutputLimiter limiter;
 128
 129     private BGPSessionStats sessionStats;
 130
 131     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final BGPSessionPreferences localPreferences,
 132             final BGPPeerRegistry peerRegistry) {
 133         this(listener, channel, remoteOpen, localPreferences.getHoldTime(), peerRegistry);
 134         this.sessionStats = new BGPSessionStats(remoteOpen, this.holdTimerValue, this.keepAlive, channel, Optional.of(localPreferences), this.tableTypes, this.addPathTypes);
 135     }
 136
 137     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final int localHoldTimer,
 138             final BGPPeerRegistry peerRegistry) {
 139         this.listener = Preconditions.checkNotNull(listener);
 140         this.channel = Preconditions.checkNotNull(channel);
 141         this.limiter = new ChannelOutputLimiter(this);
 142         this.channel.pipeline().addLast(this.limiter);
 143         this.holdTimerValue = (remoteOpen.getHoldTimer() < localHoldTimer) ? remoteOpen.getHoldTimer() : localHoldTimer;
 144         LOG.info("BGP HoldTimer new value: {}", this.holdTimerValue);
 145         this.keepAlive = this.holdTimerValue / KA_TO_DEADTIMER_RATIO;
 146         this.asNumber = AsNumberUtil.advertizedAsNumber(remoteOpen);
 147         this.peerRegistry = peerRegistry;
 148         final boolean enableExMess = BgpExtendedMessageUtil.advertizedBgpExtendedMessageCapability(remoteOpen);
 149         if (enableExMess) {
 150             this.channel.pipeline().replace(BGPMessageHeaderDecoder.class, EXTENDED_MSG_DECODER, BGPMessageHeaderDecoder.getExtendedBGPMessageHeaderDecoder());
 151         }
 152
 153         final Set<TablesKey> tts = Sets.newHashSet();
 154         final Set<BgpTableType> tats = Sets.newHashSet();
 155         final List<AddressFamilies> addPathCapabilitiesList = Lists.newArrayList();
 156         if (remoteOpen.getBgpParameters() != null) {
 157             for (final BgpParameters param : remoteOpen.getBgpParameters()) {
 158                 for (final OptionalCapabilities optCapa : param.getOptionalCapabilities()) {
 159                     final CParameters cParam = optCapa.getCParameters();
 160                     if ( cParam.getAugmentation(CParameters1.class) == null) {
 161                         continue;
 162                     }
 163                     if(cParam.getAugmentation(CParameters1.class).getMultiprotocolCapability() != null) {
 164                         final MultiprotocolCapability multi = cParam.getAugmentation(CParameters1.class).getMultiprotocolCapability();
 165                         final TablesKey tt = new TablesKey(multi.getAfi(), multi.getSafi());
 166                         LOG.trace("Added table type to sync {}", tt);
 167                         tts.add(tt);
 168                         tats.add(new BgpTableTypeImpl(tt.getAfi(), tt.getSafi()));
 169                     } else if (cParam.getAugmentation(CParameters1.class).getAddPathCapability() != null) {
 170                         final AddPathCapability addPathCap = cParam.getAugmentation(CParameters1.class).getAddPathCapability();
 171                         addPathCapabilitiesList.addAll(addPathCap.getAddressFamilies());
 172                     }
 173                 }
 174             }
 175         }
 176
 177         this.sync = new BGPSynchronization(this.listener, tts);
 178         this.tableTypes = tats;
 179         this.addPathTypes = addPathCapabilitiesList;
 180
 181         if (! this.addPathTypes.isEmpty()) {
 182             final ChannelPipeline pipeline = this.channel.pipeline();
 183             final BGPByteToMessageDecoder decoder = pipeline.get(BGPByteToMessageDecoder.class);
 184             decoder.addDecoderConstraint(MultiPathSupport.class,
 185                     MultiPathSupportImpl.createParserMultiPathSupport(this.addPathTypes));
 186         }
 187
 188         if (this.holdTimerValue != 0) {
 189             channel.eventLoop().schedule(new Runnable() {
 190                 @Override
 191                 public void run() {
 192                     handleHoldTimer();
 193                 }
 194             }, this.holdTimerValue, TimeUnit.SECONDS);
 195
 196             channel.eventLoop().schedule(new Runnable() {
 197                 @Override
 198                 public void run() {
 199                     handleKeepaliveTimer();
 200                 }
 201             }, this.keepAlive, TimeUnit.SECONDS);
 202         }
 203         this.bgpId = remoteOpen.getBgpIdentifier();
 204         this.sessionStats = new BGPSessionStats(remoteOpen, this.holdTimerValue, this.keepAlive, channel, Optional.<BGPSessionPreferences>absent(),
 205                 this.tableTypes, this.addPathTypes);
 206     }
 207
 208     @Override
 209     public synchronized void close() {
 210         if (this.state != State.IDLE && this.channel.isActive()) {
 211             this.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode()).setErrorSubcode(
 212                     BGPError.CEASE.getSubcode()).build());
 213         }
 214         this.closeWithoutMessage();
 215     }
 216
 217     /**
 218      * Handles incoming message based on their type.
 219      *
 220      * @param msg incoming message
 221      */
 222     public synchronized void handleMessage(final Notification msg) throws BGPDocumentedException {
 223         // Update last reception time
 224         this.lastMessageReceivedAt = System.nanoTime();
 225         this.sessionStats.updateReceivedMsgTotal();
 226
 227         if (msg instanceof Open) {
 228             // Open messages should not be present here
 229             this.terminate(new BGPDocumentedException(null, BGPError.FSM_ERROR));
 230         } else if (msg instanceof Notify) {
 231             // Notifications are handled internally
 232             LOG.info("Session closed because Notification message received: {} / {}", ((Notify) msg).getErrorCode(),
 233                     ((Notify) msg).getErrorSubcode());
 234             this.closeWithoutMessage();
 235             this.listener.onSessionTerminated(this, new BGPTerminationReason(
 236                     BGPError.forValue(((Notify) msg).getErrorCode(), ((Notify) msg).getErrorSubcode())));
 237             this.sessionStats.updateReceivedMsgErr((Notify) msg);
 238         } else if (msg instanceof Keepalive) {
 239             // Keepalives are handled internally
 240             LOG.trace("Received KeepAlive messsage.");
 241             this.kaCounter++;
 242             this.sessionStats.updateReceivedMsgKA();
 243             if (this.kaCounter >= 2) {
 244                 this.sync.kaReceived();
 245             }
 246         } else if (msg instanceof RouteRefresh) {
 247             this.listener.onMessage(this, msg);
 248             this.sessionStats.updateReceivedMsgRR();
 249         } else if (msg instanceof Update) {
 250             this.listener.onMessage(this, msg);
 251             this.sync.updReceived((Update) msg);
 252             this.sessionStats.updateReceivedMsgUpd();
 253         } else {
 254             LOG.warn("Ignoring unhandled message: {}.", msg.getClass());
 255         }
 256     }
 257
 258     public synchronized void endOfInput() {
 259         if (this.state == State.UP) {
 260             LOG.info(END_OF_INPUT);
 261             this.listener.onSessionDown(this, new IOException(END_OF_INPUT));
 262         }
 263     }
 264
 265     @GuardedBy("this")
 266     private ChannelFuture writeEpilogue(final ChannelFuture future, final Notification msg) {
 267         future.addListener(
 268                 new ChannelFutureListener() {
 269                     @Override
 270                     public void operationComplete(final ChannelFuture f) {
 271                         if (!f.isSuccess()) {
 272                             LOG.warn("Failed to send message {} to socket {}", msg, f.cause(), BGPSessionImpl.this.channel);
 273                         } else {
 274                             LOG.trace("Message {} sent to socket {}", msg, BGPSessionImpl.this.channel);
 275                         }
 276                     }
 277                 });
 278         this.lastMessageSentAt = System.nanoTime();
 279         this.sessionStats.updateSentMsgTotal();
 280         if (msg instanceof Update) {
 281             this.sessionStats.updateSentMsgUpd();
 282         } else if (msg instanceof Notify) {
 283             this.sessionStats.updateSentMsgErr((Notify) msg);
 284         }
 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         return writeEpilogue(this.channel.writeAndFlush(msg), msg);
 302     }
 303
 304     private synchronized void closeWithoutMessage() {
 305         LOG.info("Closing session: {}", this);
 306         removePeerSession();
 307         this.channel.close();
 308         this.state = State.IDLE;
 309     }
 310
 311     /**
 312      * Closes BGP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 313      * modified, because he initiated the closing. (To prevent concurrent modification exception).
 314      *
 315      * @param e BGPDocumentedException
 316      */
 317     private synchronized void terminate(final BGPDocumentedException e) {
 318         final BGPError error = e.getError();
 319         final byte[] data = e.getData();
 320         final NotifyBuilder builder = new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode());
 321         if (data != null && data.length != 0) {
 322             builder.setData(data);
 323         }
 324         this.writeAndFlush(builder.build());
 325         this.closeWithoutMessage();
 326
 327         this.listener.onSessionTerminated(this, new BGPTerminationReason(error));
 328     }
 329
 330     private void removePeerSession() {
 331         if (this.peerRegistry != null) {
 332             this.peerRegistry.removePeerSession(StrictBGPPeerRegistry.getIpAddress(this.channel.remoteAddress()));
 333         }
 334     }
 335
 336     /**
 337      * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 338      * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 339      * which the message was received. If the session was closed by the time this method starts to execute (the session
 340      * state will become IDLE), then rescheduling won't occur.
 341      */
 342     private synchronized void handleHoldTimer() {
 343         if (this.state == State.IDLE) {
 344             return;
 345         }
 346
 347         final long ct = System.nanoTime();
 348         final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 349
 350         if (ct >= nextHold) {
 351             LOG.debug("HoldTimer expired. {}", new Date());
 352             this.terminate(new BGPDocumentedException(BGPError.HOLD_TIMER_EXPIRED));
 353         } else {
 354             this.channel.eventLoop().schedule(new Runnable() {
 355                 @Override
 356                 public void run() {
 357                     handleHoldTimer();
 358                 }
 359             }, 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             this.sessionStats.updateSentMsgKA();
 381         }
 382         this.channel.eventLoop().schedule(new Runnable() {
 383             @Override
 384             public void run() {
 385                 handleKeepaliveTimer();
 386             }
 387         }, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 388     }
 389
 390     @Override
 391     public final String toString() {
 392         return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
 393     }
 394
 395     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 396         toStringHelper.add("channel", this.channel);
 397         toStringHelper.add("state", this.getState());
 398         return toStringHelper;
 399     }
 400
 401     @Override
 402     public Set<BgpTableType> getAdvertisedTableTypes() {
 403         return this.tableTypes;
 404     }
 405
 406     @Override
 407     public List<AddressFamilies> getAdvertisedAddPathTableTypes() {
 408         return this.addPathTypes;
 409     }
 410
 411     protected synchronized void sessionUp() {
 412         this.sessionStats.startSessionStopwatch();
 413         this.state = State.UP;
 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     synchronized boolean isWritable() {
 432         return this.channel != null && this.channel.isWritable();
 433     }
 434
 435     void schedule(final Runnable task) {
 436         Preconditions.checkState(this.channel != null);
 437         this.channel.eventLoop().submit(task);
 438     }
 439
 440     @VisibleForTesting
 441     protected synchronized void setLastMessageSentAt(final long lastMessageSentAt) {
 442         this.lastMessageSentAt = lastMessageSentAt;
 443     }
 444
 445     @Override
 446     public synchronized BgpSessionState getBgpSesionState() {
 447         return this.sessionStats.getBgpSessionState(this.state);
 448     }
 449
 450     @Override
 451     public synchronized void resetSessionStats() {
 452         this.sessionStats.resetStats();
 453     }
 454
 455     ChannelOutputLimiter getLimiter() {
 456         return this.limiter;
 457     }
 458
 459     @Override
 460     public final void channelInactive(final ChannelHandlerContext ctx) {
 461         LOG.debug("Channel {} inactive.", ctx.channel());
 462         this.endOfInput();
 463
 464         try {
 465             super.channelInactive(ctx);
 466         } catch (final Exception e) {
 467             throw new IllegalStateException("Failed to delegate channel inactive event on channel " + ctx.channel(), e);
 468         }
 469     }
 470
 471     @Override
 472     protected final void channelRead0(final ChannelHandlerContext ctx, final Notification msg) {
 473         LOG.debug("Message was received: {}", msg);
 474         try {
 475             this.handleMessage(msg);
 476         } catch (final BGPDocumentedException e) {
 477             this.terminate(e);
 478         }
 479     }
 480
 481     @Override
 482     public final void handlerAdded(final ChannelHandlerContext ctx) {
 483         this.sessionUp();
 484     }
 485
 486     @Override
 487     public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
 488         LOG.warn("BGP session encountered error", cause);
 489         if (cause.getCause() instanceof BGPDocumentedException) {
 490             this.terminate((BGPDocumentedException) cause.getCause());
 491         } else {
 492             this.close();
 493         }
 494     }
 495 }