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(
 165                     BGPError.CEASE.getSubcode()).build());
 166             this.channel.close();
 167             this.state = State.Idle;
 168         }
 169     }
 170
 171     /**
 172      * Handles incoming message based on their type.
 173      *
 174      * @param msg incoming message
 175      */
 176     @Override
 177     public synchronized void handleMessage(final Notification msg) {
 178         // Update last reception time
 179         this.lastMessageReceivedAt = System.nanoTime();
 180         this.sessionStats.updateReceivedMsgTotal();
 181
 182         if (msg instanceof Open) {
 183             // Open messages should not be present here
 184             this.terminate(BGPError.FSM_ERROR);
 185         } else if (msg instanceof Notify) {
 186             // Notifications are handled internally
 187             LOG.info("Session closed because Notification message received: {} / {}", ((Notify) msg).getErrorCode(),
 188                 ((Notify) msg).getErrorSubcode());
 189             this.closeWithoutMessage();
 190             this.listener.onSessionTerminated(this, new BGPTerminationReason(BGPError.forValue(((Notify) msg).getErrorCode(),
 191                 ((Notify) msg).getErrorSubcode())));
 192             this.sessionStats.updateReceivedMsgErr((Notify) msg);
 193         } else if (msg instanceof Keepalive) {
 194             // Keepalives are handled internally
 195             LOG.trace("Received KeepAlive messsage.");
 196             this.kaCounter++;
 197             this.sessionStats.updateReceivedMsgKA();
 198             if (this.kaCounter >= 2) {
 199                 this.sync.kaReceived();
 200             }
 201         } else {
 202             // All others are passed up
 203             this.listener.onMessage(this, msg);
 204             this.sync.updReceived((Update) msg);
 205             this.sessionStats.updateReceivedMsgUpd();
 206         }
 207     }
 208
 209     @Override
 210     public synchronized void endOfInput() {
 211         if (this.state == State.Up) {
 212             this.listener.onSessionDown(this, new IOException("End of input detected. Close the session."));
 213         }
 214     }
 215
 216     synchronized void sendMessage(final Notification msg) {
 217         try {
 218             this.channel.writeAndFlush(msg).addListener(
 219                 new ChannelFutureListener() {
 220                     @Override
 221                     public void operationComplete(final ChannelFuture f) {
 222                         if (!f.isSuccess()) {
 223                             LOG.info("Failed to send message {} to socket {}", msg, f.cause(), BGPSessionImpl.this.channel);
 224                         } else {
 225                             LOG.trace("Message {} sent to socket {}", msg, BGPSessionImpl.this.channel);
 226                         }
 227                     }
 228                 });
 229             this.lastMessageSentAt = System.nanoTime();
 230             this.sessionStats.updateSentMsgTotal();
 231             if (msg instanceof Update) {
 232                 this.sessionStats.updateSentMsgUpd();
 233             } else if (msg instanceof Notify) {
 234                 this.sessionStats.updateSentMsgErr((Notify) msg);
 235             }
 236         } catch (final Exception e) {
 237             LOG.warn("Message {} was not sent.", msg, e);
 238         }
 239     }
 240
 241     private synchronized void closeWithoutMessage() {
 242         LOG.debug("Closing session: {}", this);
 243         this.channel.close();
 244         this.state = State.Idle;
 245     }
 246
 247     /**
 248      * Closes PCEP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 249      * modified, because he initiated the closing. (To prevent concurrent modification exception).
 250      *
 251      * @param closeObject
 252      */
 253     private void terminate(final BGPError error) {
 254         this.sendMessage(new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode()).build());
 255         this.closeWithoutMessage();
 256
 257         this.listener.onSessionTerminated(this, new BGPTerminationReason(error));
 258     }
 259
 260     /**
 261      * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 262      * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 263      * which the message was received. If the session was closed by the time this method starts to execute (the session
 264      * state will become IDLE), then rescheduling won't occur.
 265      */
 266     private synchronized void handleHoldTimer() {
 267         if (this.state == State.Idle) {
 268             return;
 269         }
 270
 271         final long ct = System.nanoTime();
 272         final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 273
 274         if (ct >= nextHold) {
 275             LOG.debug("HoldTimer expired. {}", new Date());
 276             this.terminate(BGPError.HOLD_TIMER_EXPIRED);
 277         } else {
 278             this.channel.eventLoop().schedule(new Runnable() {
 279                 @Override
 280                 public void run() {
 281                     handleHoldTimer();
 282                 }
 283             }, nextHold - ct, TimeUnit.NANOSECONDS);
 284         }
 285     }
 286
 287     /**
 288      * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 289      * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 290      * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 291      * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 292      */
 293     private synchronized void handleKeepaliveTimer() {
 294         if (this.state == State.Idle) {
 295             return;
 296         }
 297
 298         final long ct = System.nanoTime();
 299         long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 300
 301         if (ct >= nextKeepalive) {
 302             this.sendMessage(KEEP_ALIVE);
 303             nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 304             this.sessionStats.updateSentMsgKA();
 305         }
 306         this.channel.eventLoop().schedule(new Runnable() {
 307             @Override
 308             public void run() {
 309                 handleKeepaliveTimer();
 310             }
 311         }, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 312     }
 313
 314     @Override
 315     public final String toString() {
 316         return addToStringAttributes(Objects.toStringHelper(this)).toString();
 317     }
 318
 319     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 320         toStringHelper.add("channel", this.channel);
 321         toStringHelper.add("state", this.getState());
 322         return toStringHelper;
 323     }
 324
 325     @Override
 326     public Set<BgpTableType> getAdvertisedTableTypes() {
 327         return this.tableTypes;
 328     }
 329
 330     @Override
 331     protected synchronized void sessionUp() {
 332         this.sessionStats.startSessionStopwatch();
 333         this.state = State.Up;
 334         this.listener.onSessionUp(this);
 335     }
 336
 337     public synchronized State getState() {
 338         return this.state;
 339     }
 340
 341     @Override
 342     public final Ipv4Address getBgpId() {
 343         return this.bgpId;
 344     }
 345
 346     @Override
 347     public final AsNumber getAsNumber() {
 348         return this.asNumber;
 349     }
 350
 351     synchronized boolean isWritable() {
 352         return this.channel != null && this.channel.isWritable();
 353     }
 354
 355     synchronized void schedule(final Runnable task) {
 356         Preconditions.checkState(this.channel != null);
 357         this.channel.eventLoop().submit(task);
 358     }
 359
 360     @VisibleForTesting
 361     protected synchronized void setLastMessageSentAt(final long lastMessageSentAt) {
 362         this.lastMessageSentAt = lastMessageSentAt;
 363     }
 364
 365     @Override
 366     public synchronized BgpSessionState getBgpSesionState() {
 367         return this.sessionStats.getBgpSessionState(this.state);
 368     }
 369
 370     @Override
 371     public synchronized void resetSessionStats() {
 372         this.sessionStats.resetStats();
 373     }
 374 }