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.Sets;
  16 import io.netty.channel.Channel;
  17 import io.netty.channel.ChannelFuture;
  18 import io.netty.channel.ChannelFutureListener;
  19 import java.io.IOException;
  20 import java.util.Date;
  21 import java.util.Set;
  22 import java.util.concurrent.TimeUnit;
  23 import javax.annotation.concurrent.GuardedBy;
  24 import org.opendaylight.controller.config.yang.bgp.rib.impl.BgpSessionState;
  25 import org.opendaylight.protocol.bgp.parser.AsNumberUtil;
  26 import org.opendaylight.protocol.bgp.parser.BGPError;
  27 import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl;
  28 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
  29 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  30 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionStatistics;
  31 import org.opendaylight.protocol.bgp.rib.spi.BGPSession;
  32 import org.opendaylight.protocol.bgp.rib.spi.BGPSessionListener;
  33 import org.opendaylight.protocol.bgp.rib.spi.BGPTerminationReason;
  34 import org.opendaylight.protocol.framework.AbstractProtocolSession;
  35 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.AsNumber;
  36 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
  37 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Keepalive;
  38 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.KeepaliveBuilder;
  39 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Notify;
  40 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.NotifyBuilder;
  41 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Open;
  42 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Update;
  43 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.BgpParameters;
  44 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.bgp.parameters.OptionalCapabilities;
  45 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.bgp.parameters.optional.capabilities.CParameters;
  46 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.BgpTableType;
  47 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.open.bgp.parameters.optional.capabilities.c.parameters.MultiprotocolCase;
  48 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.TablesKey;
  49 import org.opendaylight.yangtools.yang.binding.Notification;
  50 import org.slf4j.Logger;
  51 import org.slf4j.LoggerFactory;
  52
  53 @VisibleForTesting
  54 public class BGPSessionImpl extends AbstractProtocolSession<Notification> implements BGPSession, BGPSessionStatistics {
  55
  56     private static final Logger LOG = LoggerFactory.getLogger(BGPSessionImpl.class);
  57
  58     private static final Notification KEEP_ALIVE = new KeepaliveBuilder().build();
  59
  60     private static final int KA_TO_DEADTIMER_RATIO = 3;
  61
  62     /**
  63      * Internal session state.
  64      */
  65     public enum State {
  66         /**
  67          * The session object is created by the negotiator in OpenConfirm state. While in this state, the session object
  68          * is half-alive, e.g. the timers are running, but the session is not completely up, e.g. it has not been
  69          * announced to the listener. If the session is torn down in this state, we do not inform the listener.
  70          */
  71         OPEN_CONFIRM,
  72         /**
  73          * The session has been completely established.
  74          */
  75         UP,
  76         /**
  77          * The session has been closed. It will not be resurrected.
  78          */
  79         IDLE,
  80     }
  81
  82     /**
  83      * System.nanoTime value about when was sent the last message.
  84      */
  85     @VisibleForTesting
  86     private long lastMessageSentAt;
  87
  88     /**
  89      * System.nanoTime value about when was received the last message
  90      */
  91     private long lastMessageReceivedAt;
  92
  93     private final BGPSessionListener listener;
  94
  95     private final BGPSynchronization sync;
  96
  97     private int kaCounter = 0;
  98
  99     private final Channel channel;
 100
 101     @GuardedBy("this")
 102     private State state = State.OPEN_CONFIRM;
 103
 104     private final Set<BgpTableType> tableTypes;
 105     private final int holdTimerValue;
 106     private final int keepAlive;
 107     private final AsNumber asNumber;
 108     private final Ipv4Address bgpId;
 109     private final BGPPeerRegistry peerRegistry;
 110     private final ChannelOutputLimiter limiter;
 111
 112     private BGPSessionStats sessionStats;
 113
 114     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final BGPSessionPreferences localPreferences,
 115             final BGPPeerRegistry peerRegistry) {
 116         this(listener, channel, remoteOpen, localPreferences.getHoldTime(), peerRegistry);
 117         this.sessionStats = new BGPSessionStats(remoteOpen, this.holdTimerValue, this.keepAlive, channel, Optional.of(localPreferences), this.tableTypes);
 118     }
 119
 120     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final int localHoldTimer,
 121             final BGPPeerRegistry peerRegistry) {
 122         this.listener = Preconditions.checkNotNull(listener);
 123         this.channel = Preconditions.checkNotNull(channel);
 124         this.limiter = new ChannelOutputLimiter(this);
 125         this.channel.pipeline().addLast(this.limiter);
 126         this.holdTimerValue = (remoteOpen.getHoldTimer() < localHoldTimer) ? remoteOpen.getHoldTimer() : localHoldTimer;
 127         LOG.info("BGP HoldTimer new value: {}", this.holdTimerValue);
 128         this.keepAlive = this.holdTimerValue / KA_TO_DEADTIMER_RATIO;
 129         this.asNumber = AsNumberUtil.advertizedAsNumber(remoteOpen);
 130         this.peerRegistry = peerRegistry;
 131
 132         final Set<TablesKey> tts = Sets.newHashSet();
 133         final Set<BgpTableType> tats = Sets.newHashSet();
 134         if (remoteOpen.getBgpParameters() != null) {
 135             for (final BgpParameters param : remoteOpen.getBgpParameters()) {
 136                 for (final OptionalCapabilities optCapa : param.getOptionalCapabilities()) {
 137                     final CParameters cp = optCapa.getCParameters();
 138                     if (cp instanceof MultiprotocolCase) {
 139                         final TablesKey tt = new TablesKey(((MultiprotocolCase) cp).getMultiprotocolCapability().getAfi(),
 140                                 ((MultiprotocolCase) cp).getMultiprotocolCapability().getSafi());
 141                         LOG.trace("Added table type to sync {}", tt);
 142                         tts.add(tt);
 143                         tats.add(new BgpTableTypeImpl(tt.getAfi(), tt.getSafi()));
 144                     }
 145                 }
 146             }
 147         }
 148
 149         this.sync = new BGPSynchronization(this.listener, tts);
 150         this.tableTypes = tats;
 151
 152         if (this.holdTimerValue != 0) {
 153             channel.eventLoop().schedule(new Runnable() {
 154                 @Override
 155                 public void run() {
 156                     handleHoldTimer();
 157                 }
 158             }, this.holdTimerValue, TimeUnit.SECONDS);
 159
 160             channel.eventLoop().schedule(new Runnable() {
 161                 @Override
 162                 public void run() {
 163                     handleKeepaliveTimer();
 164                 }
 165             }, this.keepAlive, TimeUnit.SECONDS);
 166         }
 167         this.bgpId = remoteOpen.getBgpIdentifier();
 168         this.sessionStats = new BGPSessionStats(remoteOpen, this.holdTimerValue, this.keepAlive, channel, Optional.<BGPSessionPreferences>absent(),
 169                 this.tableTypes);
 170     }
 171
 172     @Override
 173     public synchronized void close() {
 174         LOG.info("Closing session: {}", this);
 175
 176         if (this.state != State.IDLE) {
 177             this.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode()).setErrorSubcode(
 178                     BGPError.CEASE.getSubcode()).build());
 179             removePeerSession();
 180             this.channel.close();
 181             this.state = State.IDLE;
 182         }
 183     }
 184
 185     /**
 186      * Handles incoming message based on their type.
 187      *
 188      * @param msg incoming message
 189      */
 190     @Override
 191     public synchronized void handleMessage(final Notification msg) {
 192         // Update last reception time
 193         this.lastMessageReceivedAt = System.nanoTime();
 194         this.sessionStats.updateReceivedMsgTotal();
 195
 196         if (msg instanceof Open) {
 197             // Open messages should not be present here
 198             this.terminate(BGPError.FSM_ERROR);
 199         } else if (msg instanceof Notify) {
 200             // Notifications are handled internally
 201             LOG.info("Session closed because Notification message received: {} / {}", ((Notify) msg).getErrorCode(),
 202                 ((Notify) msg).getErrorSubcode());
 203             this.closeWithoutMessage();
 204             this.listener.onSessionTerminated(this, new BGPTerminationReason(BGPError.forValue(((Notify) msg).getErrorCode(),
 205                 ((Notify) msg).getErrorSubcode())));
 206             this.sessionStats.updateReceivedMsgErr((Notify) msg);
 207         } else if (msg instanceof Keepalive) {
 208             // Keepalives are handled internally
 209             LOG.trace("Received KeepAlive messsage.");
 210             this.kaCounter++;
 211             this.sessionStats.updateReceivedMsgKA();
 212             if (this.kaCounter >= 2) {
 213                 this.sync.kaReceived();
 214             }
 215         } else {
 216             // All others are passed up
 217             this.listener.onMessage(this, msg);
 218             this.sync.updReceived((Update) msg);
 219             this.sessionStats.updateReceivedMsgUpd();
 220         }
 221     }
 222
 223     @Override
 224     public synchronized void endOfInput() {
 225         if (this.state == State.UP) {
 226             this.listener.onSessionDown(this, new IOException("End of input detected. Close the session."));
 227         }
 228     }
 229
 230     @GuardedBy("this")
 231     private void writeEpilogue(final ChannelFuture future, final Notification msg) {
 232         future.addListener(
 233             new ChannelFutureListener() {
 234                 @Override
 235                 public void operationComplete(final ChannelFuture f) {
 236                     if (!f.isSuccess()) {
 237                         LOG.info("Failed to send message {} to socket {}", msg, f.cause(), BGPSessionImpl.this.channel);
 238                     } else {
 239                         LOG.trace("Message {} sent to socket {}", msg, BGPSessionImpl.this.channel);
 240                     }
 241                 }
 242             });
 243         this.lastMessageSentAt = System.nanoTime();
 244         this.sessionStats.updateSentMsgTotal();
 245         if (msg instanceof Update) {
 246             this.sessionStats.updateSentMsgUpd();
 247         } else if (msg instanceof Notify) {
 248             this.sessionStats.updateSentMsgErr((Notify) msg);
 249         }
 250     }
 251
 252     void flush() {
 253         this.channel.flush();
 254     }
 255
 256     synchronized void write(final Notification msg) {
 257         try {
 258             writeEpilogue(this.channel.write(msg), msg);
 259         } catch (final Exception e) {
 260             LOG.warn("Message {} was not sent.", msg, e);
 261         }
 262     }
 263
 264     synchronized void writeAndFlush(final Notification msg) {
 265         writeEpilogue(this.channel.writeAndFlush(msg), msg);
 266     }
 267
 268     private synchronized void closeWithoutMessage() {
 269         LOG.debug("Closing session: {}", this);
 270         removePeerSession();
 271         this.channel.close();
 272         this.state = State.IDLE;
 273     }
 274
 275     /**
 276      * Closes PCEP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 277      * modified, because he initiated the closing. (To prevent concurrent modification exception).
 278      *
 279      * @param closeObject
 280      */
 281     private void terminate(final BGPError error) {
 282         this.writeAndFlush(new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode()).build());
 283         this.closeWithoutMessage();
 284
 285         this.listener.onSessionTerminated(this, new BGPTerminationReason(error));
 286     }
 287
 288     private void removePeerSession() {
 289         if (this.peerRegistry != null) {
 290             this.peerRegistry.removePeerSession(StrictBGPPeerRegistry.getIpAddress(this.channel.remoteAddress()));
 291         }
 292     }
 293
 294     /**
 295      * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 296      * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 297      * which the message was received. If the session was closed by the time this method starts to execute (the session
 298      * state will become IDLE), then rescheduling won't occur.
 299      */
 300     private synchronized void handleHoldTimer() {
 301         if (this.state == State.IDLE) {
 302             return;
 303         }
 304
 305         final long ct = System.nanoTime();
 306         final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 307
 308         if (ct >= nextHold) {
 309             LOG.debug("HoldTimer expired. {}", new Date());
 310             this.terminate(BGPError.HOLD_TIMER_EXPIRED);
 311         } else {
 312             this.channel.eventLoop().schedule(new Runnable() {
 313                 @Override
 314                 public void run() {
 315                     handleHoldTimer();
 316                 }
 317             }, nextHold - ct, TimeUnit.NANOSECONDS);
 318         }
 319     }
 320
 321     /**
 322      * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 323      * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 324      * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 325      * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 326      */
 327     private synchronized void handleKeepaliveTimer() {
 328         if (this.state == State.IDLE) {
 329             return;
 330         }
 331
 332         final long ct = System.nanoTime();
 333         long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 334
 335         if (ct >= nextKeepalive) {
 336             this.writeAndFlush(KEEP_ALIVE);
 337             nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 338             this.sessionStats.updateSentMsgKA();
 339         }
 340         this.channel.eventLoop().schedule(new Runnable() {
 341             @Override
 342             public void run() {
 343                 handleKeepaliveTimer();
 344             }
 345         }, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 346     }
 347
 348     @Override
 349     public final String toString() {
 350         return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
 351     }
 352
 353     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 354         toStringHelper.add("channel", this.channel);
 355         toStringHelper.add("state", this.getState());
 356         return toStringHelper;
 357     }
 358
 359     @Override
 360     public Set<BgpTableType> getAdvertisedTableTypes() {
 361         return this.tableTypes;
 362     }
 363
 364     @Override
 365     protected synchronized void sessionUp() {
 366         this.sessionStats.startSessionStopwatch();
 367         this.state = State.UP;
 368         this.listener.onSessionUp(this);
 369     }
 370
 371     public synchronized State getState() {
 372         return this.state;
 373     }
 374
 375     @Override
 376     public final Ipv4Address getBgpId() {
 377         return this.bgpId;
 378     }
 379
 380     @Override
 381     public final AsNumber getAsNumber() {
 382         return this.asNumber;
 383     }
 384
 385     synchronized boolean isWritable() {
 386         return this.channel != null && this.channel.isWritable();
 387     }
 388
 389     void schedule(final Runnable task) {
 390         Preconditions.checkState(this.channel != null);
 391         this.channel.eventLoop().submit(task);
 392     }
 393
 394     @VisibleForTesting
 395     protected synchronized void setLastMessageSentAt(final long lastMessageSentAt) {
 396         this.lastMessageSentAt = lastMessageSentAt;
 397     }
 398
 399     @Override
 400     public synchronized BgpSessionState getBgpSesionState() {
 401         return this.sessionStats.getBgpSessionState(this.state);
 402     }
 403
 404     @Override
 405     public synchronized void resetSessionStats() {
 406         this.sessionStats.resetStats();
 407     }
 408
 409     ChannelOutputLimiter getLimiter() {
 410         return this.limiter;
 411     }
 412 }