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 io.netty.channel.Channel;
  11 import io.netty.util.Timeout;
  12 import io.netty.util.Timer;
  13 import io.netty.util.TimerTask;
  14
  15 import java.io.IOException;
  16 import java.util.Date;
  17 import java.util.Set;
  18 import java.util.concurrent.TimeUnit;
  19
  20 import javax.annotation.concurrent.GuardedBy;
  21
  22 import org.opendaylight.protocol.bgp.parser.AsNumberUtil;
  23 import org.opendaylight.protocol.bgp.parser.BGPError;
  24 import org.opendaylight.protocol.bgp.parser.BGPSession;
  25 import org.opendaylight.protocol.bgp.parser.BGPSessionListener;
  26 import org.opendaylight.protocol.bgp.parser.BGPTerminationReason;
  27 import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl;
  28 import org.opendaylight.protocol.framework.AbstractProtocolSession;
  29 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.AsNumber;
  30 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
  31 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Keepalive;
  32 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.KeepaliveBuilder;
  33 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Notify;
  34 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.NotifyBuilder;
  35 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Open;
  36 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Update;
  37 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.BgpParameters;
  38 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.bgp.parameters.CParameters;
  39 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.BgpTableType;
  40 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.open.bgp.parameters.c.parameters.MultiprotocolCase;
  41 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.TablesKey;
  42 import org.opendaylight.yangtools.yang.binding.Notification;
  43 import org.slf4j.Logger;
  44 import org.slf4j.LoggerFactory;
  45
  46 import com.google.common.annotations.VisibleForTesting;
  47 import com.google.common.base.Objects;
  48 import com.google.common.base.Objects.ToStringHelper;
  49 import com.google.common.base.Preconditions;
  50 import com.google.common.collect.Sets;
  51
  52 @VisibleForTesting
  53 public class BGPSessionImpl extends AbstractProtocolSession<Notification> implements BGPSession {
  54
  55         private static final Logger LOG = LoggerFactory.getLogger(BGPSessionImpl.class);
  56
  57         /*
  58          * 240
  59          */
  60         private static final int DEFAULT_HOLD_TIMER_VALUE = 15;
  61
  62         private static final Notification KEEP_ALIVE = new KeepaliveBuilder().build();
  63
  64         /**
  65          * Internal session state.
  66          */
  67         public enum State {
  68                 /**
  69                  * The session object is created by the negotiator in OpenConfirm state. While in this state, the session object
  70                  * is half-alive, e.g. the timers are running, but the session is not completely up, e.g. it has not been
  71                  * announced to the listener. If the session is torn down in this state, we do not inform the listener.
  72                  */
  73                 OpenConfirm,
  74                 /**
  75                  * The session has been completely established.
  76                  */
  77                 Up,
  78                 /**
  79                  * The session has been closed. It will not be resurrected.
  80                  */
  81                 Idle,
  82         }
  83
  84         /**
  85          * System.nanoTime value about when was sent the last message Protected to be updated also in tests.
  86          */
  87         @VisibleForTesting
  88         protected long lastMessageSentAt;
  89
  90         /**
  91          * System.nanoTime value about when was received the last message
  92          */
  93         private long lastMessageReceivedAt;
  94
  95         private final BGPSessionListener listener;
  96
  97         /**
  98          * Timer object grouping FSM Timers
  99          */
 100         private final Timer stateTimer;
 101
 102         private final BGPSynchronization sync;
 103
 104         private int kaCounter = 0;
 105
 106         private final Channel channel;
 107
 108         @GuardedBy("this")
 109         private State state = State.OpenConfirm;
 110
 111
 112         private final Set<BgpTableType> tableTypes;
 113         private final int holdTimerValue;
 114         private final int keepAlive;
 115         private final AsNumber asNumber;
 116         private final Ipv4Address bgpId;
 117
 118         BGPSessionImpl(final Timer timer, final BGPSessionListener listener, final Channel channel, final Open remoteOpen) {
 119                 this.listener = Preconditions.checkNotNull(listener);
 120                 this.stateTimer = Preconditions.checkNotNull(timer);
 121                 this.channel = Preconditions.checkNotNull(channel);
 122                 this.keepAlive = remoteOpen.getHoldTimer() / 3;
 123                 this.holdTimerValue = remoteOpen.getHoldTimer();
 124                 this.asNumber = AsNumberUtil.advertizedAsNumber(remoteOpen);
 125
 126                 final Set<TablesKey> tts = Sets.newHashSet();
 127                 final Set<BgpTableType> tats = Sets.newHashSet();
 128                 if (remoteOpen.getBgpParameters() != null) {
 129                         for (final BgpParameters param : remoteOpen.getBgpParameters()) {
 130                                 final CParameters cp = param.getCParameters();
 131                                 if (cp instanceof MultiprotocolCase) {
 132                                         final TablesKey tt = new TablesKey(((MultiprotocolCase) cp).getMultiprotocolCapability().getAfi(), ((MultiprotocolCase) cp).getMultiprotocolCapability().getSafi());
 133                                         LOG.trace("Added table type to sync {}", tt);
 134                                         tts.add(tt);
 135                                         tats.add(new BgpTableTypeImpl(tt.getAfi(), tt.getSafi()));
 136                                 }
 137                         }
 138                 }
 139
 140                 this.sync = new BGPSynchronization(this, this.listener, tts);
 141                 this.tableTypes = tats;
 142
 143                 if (remoteOpen.getHoldTimer() != 0) {
 144                         this.stateTimer.newTimeout(new TimerTask() {
 145
 146                                 @Override
 147                                 public void run(final Timeout timeout) throws Exception {
 148                                         handleHoldTimer();
 149                                 }
 150                         }, remoteOpen.getHoldTimer(), TimeUnit.SECONDS);
 151
 152                         this.stateTimer.newTimeout(new TimerTask() {
 153                                 @Override
 154                                 public void run(final Timeout timeout) throws Exception {
 155                                         handleKeepaliveTimer();
 156                                 }
 157                         }, this.keepAlive, TimeUnit.SECONDS);
 158                 }
 159                 this.bgpId = remoteOpen.getBgpIdentifier();
 160         }
 161
 162         @Override
 163         public synchronized void close() {
 164                 LOG.debug("Closing session: {}", this);
 165                 if (this.state != State.Idle) {
 166                         this.sendMessage(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode()).build());
 167                         this.channel.close();
 168                         this.state = State.Idle;
 169                 }
 170         }
 171
 172         /**
 173          * Handles incoming message based on their type.
 174          *
 175          * @param msg incoming message
 176          */
 177         @Override
 178         public void handleMessage(final Notification msg) {
 179                 // Update last reception time
 180                 this.lastMessageReceivedAt = System.nanoTime();
 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,
 191                                         new BGPTerminationReason(BGPError.forValue(((Notify) msg).getErrorCode(), ((Notify) msg).getErrorSubcode())));
 192                 } else if (msg instanceof Keepalive) {
 193                         // Keepalives are handled internally
 194                         LOG.debug("Received KeepAlive messsage.");
 195                         this.kaCounter++;
 196                         if (this.kaCounter >= 2) {
 197                                 this.sync.kaReceived();
 198                         }
 199                 } else {
 200                         // All others are passed up
 201                         this.listener.onMessage(this, msg);
 202                         this.sync.updReceived((Update) msg);
 203                 }
 204         }
 205
 206         @Override
 207         public synchronized void endOfInput() {
 208                 if (this.state == State.Up) {
 209                         this.listener.onSessionDown(this, new IOException("End of input detected. Close the session."));
 210                 }
 211         }
 212
 213         void sendMessage(final Notification msg) {
 214                 try {
 215                         this.channel.writeAndFlush(msg);
 216                         this.lastMessageSentAt = System.nanoTime();
 217                         LOG.debug("Sent message: {}", msg);
 218                 } catch (final Exception e) {
 219                         LOG.warn("Message {} was not sent.", msg, e);
 220                 }
 221         }
 222
 223         private synchronized void closeWithoutMessage() {
 224                 LOG.debug("Closing session: {}", this);
 225                 this.channel.close();
 226                 this.state = State.Idle;
 227         }
 228
 229         /**
 230          * Closes PCEP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 231          * modified, because he initiated the closing. (To prevent concurrent modification exception).
 232          *
 233          * @param closeObject
 234          */
 235         private void terminate(final BGPError error) {
 236                 this.sendMessage(new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode()).build());
 237                 this.closeWithoutMessage();
 238
 239                 this.listener.onSessionTerminated(this, new BGPTerminationReason(error));
 240         }
 241
 242         /**
 243          * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 244          * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 245          * which the message was received. If the session was closed by the time this method starts to execute (the session
 246          * state will become IDLE), then rescheduling won't occur.
 247          */
 248         private synchronized void handleHoldTimer() {
 249                 if (this.state == State.Idle) {
 250                         return;
 251                 }
 252
 253                 final long ct = System.nanoTime();
 254                 final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(holdTimerValue);
 255
 256                 if (ct >= nextHold) {
 257                         LOG.debug("HoldTimer expired. " + new Date());
 258                         this.terminate(BGPError.HOLD_TIMER_EXPIRED);
 259                 } else {
 260                         this.stateTimer.newTimeout(new TimerTask() {
 261                                 @Override
 262                                 public void run(final Timeout timeout) throws Exception {
 263                                         handleHoldTimer();
 264                                 }
 265                         }, nextHold - ct, TimeUnit.NANOSECONDS);
 266                 }
 267         }
 268
 269         /**
 270          * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 271          * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 272          * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 273          * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 274          */
 275         private synchronized void handleKeepaliveTimer() {
 276                 if (this.state == State.Idle) {
 277                         return;
 278                 }
 279
 280                 final long ct = System.nanoTime();
 281                 long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 282
 283                 if (ct >= nextKeepalive) {
 284                         this.sendMessage(KEEP_ALIVE);
 285                         nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 286                 }
 287                 this.stateTimer.newTimeout(new TimerTask() {
 288                         @Override
 289                         public void run(final Timeout timeout) throws Exception {
 290                                 handleKeepaliveTimer();
 291                         }
 292                 }, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 293         }
 294
 295         @Override
 296         public final String toString() {
 297                 return addToStringAttributes(Objects.toStringHelper(this)).toString();
 298         }
 299
 300         protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 301                 toStringHelper.add("channel", this.channel);
 302                 toStringHelper.add("state", this.state);
 303                 return toStringHelper;
 304         }
 305
 306         @Override
 307         public Set<BgpTableType> getAdvertisedTableTypes() {
 308                 return this.tableTypes;
 309         }
 310
 311         @Override
 312         protected synchronized void sessionUp() {
 313                 this.state = State.Up;
 314                 this.listener.onSessionUp(this);
 315         }
 316
 317         public synchronized State getState() {
 318                 return this.state;
 319         }
 320
 321         @Override
 322         public final Ipv4Address getBgpId() {
 323                 return this.bgpId;
 324         }
 325
 326         @Override
 327         public final AsNumber getAsNumber() {
 328                 return this.asNumber;
 329         }
 330 }