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         private static final Notification KEEP_ALIVE = new KeepaliveBuilder().build();
  58
  59         /**
  60          * Internal session state.
  61          */
  62         public enum State {
  63                 /**
  64                  * The session object is created by the negotiator in OpenConfirm state. While in this state, the session object
  65                  * is half-alive, e.g. the timers are running, but the session is not completely up, e.g. it has not been
  66                  * announced to the listener. If the session is torn down in this state, we do not inform the listener.
  67                  */
  68                 OpenConfirm,
  69                 /**
  70                  * The session has been completely established.
  71                  */
  72                 Up,
  73                 /**
  74                  * The session has been closed. It will not be resurrected.
  75                  */
  76                 Idle,
  77         }
  78
  79         /**
  80          * System.nanoTime value about when was sent the last message Protected to be updated also in tests.
  81          */
  82         @VisibleForTesting
  83         protected long lastMessageSentAt;
  84
  85         /**
  86          * System.nanoTime value about when was received the last message
  87          */
  88         private long lastMessageReceivedAt;
  89
  90         private final BGPSessionListener listener;
  91
  92         /**
  93          * Timer object grouping FSM Timers
  94          */
  95         private final Timer stateTimer;
  96
  97         private final BGPSynchronization sync;
  98
  99         private int kaCounter = 0;
 100
 101         private final Channel channel;
 102
 103         @GuardedBy("this")
 104         private State state = State.OpenConfirm;
 105
 106
 107         private final Set<BgpTableType> tableTypes;
 108         private final int holdTimerValue;
 109         private final int keepAlive;
 110         private final AsNumber asNumber;
 111         private final Ipv4Address bgpId;
 112
 113         BGPSessionImpl(final Timer timer, final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final int localHoldTimer) {
 114                 this.listener = Preconditions.checkNotNull(listener);
 115                 this.stateTimer = Preconditions.checkNotNull(timer);
 116                 this.channel = Preconditions.checkNotNull(channel);
 117                 this.holdTimerValue = (remoteOpen.getHoldTimer() < localHoldTimer) ? remoteOpen.getHoldTimer() : localHoldTimer;
 118                 LOG.info("HoldTimer new value: {}", this.holdTimerValue);
 119                 this.keepAlive = this.holdTimerValue / 3;
 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(), ((MultiprotocolCase) cp).getMultiprotocolCapability().getSafi());
 129                                         LOG.trace("Added table type to sync {}", tt);
 130                                         tts.add(tt);
 131                                         tats.add(new BgpTableTypeImpl(tt.getAfi(), tt.getSafi()));
 132                                 }
 133                         }
 134                 }
 135
 136                 this.sync = new BGPSynchronization(this, this.listener, tts);
 137                 this.tableTypes = tats;
 138
 139                 if (this.holdTimerValue != 0) {
 140                         this.stateTimer.newTimeout(new TimerTask() {
 141
 142                                 @Override
 143                                 public void run(final Timeout timeout) throws Exception {
 144                                         handleHoldTimer();
 145                                 }
 146                         }, this.holdTimerValue, TimeUnit.SECONDS);
 147
 148                         this.stateTimer.newTimeout(new TimerTask() {
 149                                 @Override
 150                                 public void run(final Timeout timeout) throws Exception {
 151                                         handleKeepaliveTimer();
 152                                 }
 153                         }, this.keepAlive, TimeUnit.SECONDS);
 154                 }
 155                 this.bgpId = remoteOpen.getBgpIdentifier();
 156         }
 157
 158         @Override
 159         public synchronized void close() {
 160                 LOG.debug("Closing session: {}", this);
 161                 if (this.state != State.Idle) {
 162                         this.sendMessage(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode()).build());
 163                         this.channel.close();
 164                         this.state = State.Idle;
 165                 }
 166         }
 167
 168         /**
 169          * Handles incoming message based on their type.
 170          *
 171          * @param msg incoming message
 172          */
 173         @Override
 174         public void handleMessage(final Notification msg) {
 175                 // Update last reception time
 176                 this.lastMessageReceivedAt = System.nanoTime();
 177
 178                 if (msg instanceof Open) {
 179                         // Open messages should not be present here
 180                         this.terminate(BGPError.FSM_ERROR);
 181                 } else if (msg instanceof Notify) {
 182                         // Notifications are handled internally
 183                         LOG.info("Session closed because Notification message received: {} / {}", ((Notify) msg).getErrorCode(),
 184                                         ((Notify) msg).getErrorSubcode());
 185                         this.closeWithoutMessage();
 186                         this.listener.onSessionTerminated(this,
 187                                         new BGPTerminationReason(BGPError.forValue(((Notify) msg).getErrorCode(), ((Notify) msg).getErrorSubcode())));
 188                 } else if (msg instanceof Keepalive) {
 189                         // Keepalives are handled internally
 190                         LOG.debug("Received KeepAlive messsage.");
 191                         this.kaCounter++;
 192                         if (this.kaCounter >= 2) {
 193                                 this.sync.kaReceived();
 194                         }
 195                 } else {
 196                         // All others are passed up
 197                         this.listener.onMessage(this, msg);
 198                         this.sync.updReceived((Update) msg);
 199                 }
 200         }
 201
 202         @Override
 203         public synchronized void endOfInput() {
 204                 if (this.state == State.Up) {
 205                         this.listener.onSessionDown(this, new IOException("End of input detected. Close the session."));
 206                 }
 207         }
 208
 209         void sendMessage(final Notification msg) {
 210                 try {
 211                         this.channel.writeAndFlush(msg);
 212                         this.lastMessageSentAt = System.nanoTime();
 213                         LOG.debug("Sent message: {}", msg);
 214                 } catch (final Exception e) {
 215                         LOG.warn("Message {} was not sent.", msg, e);
 216                 }
 217         }
 218
 219         private synchronized void closeWithoutMessage() {
 220                 LOG.debug("Closing session: {}", this);
 221                 this.channel.close();
 222                 this.state = State.Idle;
 223         }
 224
 225         /**
 226          * Closes PCEP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 227          * modified, because he initiated the closing. (To prevent concurrent modification exception).
 228          *
 229          * @param closeObject
 230          */
 231         private void terminate(final BGPError error) {
 232                 this.sendMessage(new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode()).build());
 233                 this.closeWithoutMessage();
 234
 235                 this.listener.onSessionTerminated(this, new BGPTerminationReason(error));
 236         }
 237
 238         /**
 239          * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 240          * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 241          * which the message was received. If the session was closed by the time this method starts to execute (the session
 242          * state will become IDLE), then rescheduling won't occur.
 243          */
 244         private synchronized void handleHoldTimer() {
 245                 if (this.state == State.Idle) {
 246                         return;
 247                 }
 248
 249                 final long ct = System.nanoTime();
 250                 final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 251
 252                 if (ct >= nextHold) {
 253                         LOG.debug("HoldTimer expired. " + new Date());
 254                         this.terminate(BGPError.HOLD_TIMER_EXPIRED);
 255                 } else {
 256                         this.stateTimer.newTimeout(new TimerTask() {
 257                                 @Override
 258                                 public void run(final Timeout timeout) throws Exception {
 259                                         handleHoldTimer();
 260                                 }
 261                         }, nextHold - ct, TimeUnit.NANOSECONDS);
 262                 }
 263         }
 264
 265         /**
 266          * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 267          * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 268          * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 269          * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 270          */
 271         private synchronized void handleKeepaliveTimer() {
 272                 if (this.state == State.Idle) {
 273                         return;
 274                 }
 275
 276                 final long ct = System.nanoTime();
 277                 long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 278
 279                 if (ct >= nextKeepalive) {
 280                         this.sendMessage(KEEP_ALIVE);
 281                         nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 282                 }
 283                 this.stateTimer.newTimeout(new TimerTask() {
 284                         @Override
 285                         public void run(final Timeout timeout) throws Exception {
 286                                 handleKeepaliveTimer();
 287                         }
 288                 }, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 289         }
 290
 291         @Override
 292         public final String toString() {
 293                 return addToStringAttributes(Objects.toStringHelper(this)).toString();
 294         }
 295
 296         protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 297                 toStringHelper.add("channel", this.channel);
 298                 toStringHelper.add("state", this.state);
 299                 return toStringHelper;
 300         }
 301
 302         @Override
 303         public Set<BgpTableType> getAdvertisedTableTypes() {
 304                 return this.tableTypes;
 305         }
 306
 307         @Override
 308         protected synchronized void sessionUp() {
 309                 this.state = State.Up;
 310                 this.listener.onSessionUp(this);
 311         }
 312
 313         public synchronized State getState() {
 314                 return this.state;
 315         }
 316
 317         @Override
 318         public final Ipv4Address getBgpId() {
 319                 return this.bgpId;
 320         }
 321
 322         @Override
 323         public final AsNumber getAsNumber() {
 324                 return this.asNumber;
 325         }
 326 }