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