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.concepts.BGPTableType;
  23 import org.opendaylight.protocol.bgp.parser.BGPError;
  24 import org.opendaylight.protocol.bgp.parser.BGPMessage;
  25 import org.opendaylight.protocol.bgp.parser.BGPParameter;
  26 import org.opendaylight.protocol.bgp.parser.BGPSession;
  27 import org.opendaylight.protocol.bgp.parser.BGPSessionListener;
  28 import org.opendaylight.protocol.bgp.parser.BGPTerminationReason;
  29 import org.opendaylight.protocol.bgp.parser.message.BGPKeepAliveMessage;
  30 import org.opendaylight.protocol.bgp.parser.message.BGPNotificationMessage;
  31 import org.opendaylight.protocol.bgp.parser.message.BGPOpenMessage;
  32 import org.opendaylight.protocol.bgp.parser.parameter.MultiprotocolCapability;
  33 import org.opendaylight.protocol.framework.AbstractProtocolSession;
  34 import org.slf4j.Logger;
  35 import org.slf4j.LoggerFactory;
  36
  37 import com.google.common.annotations.VisibleForTesting;
  38 import com.google.common.base.Objects;
  39 import com.google.common.base.Objects.ToStringHelper;
  40 import com.google.common.base.Preconditions;
  41 import com.google.common.collect.Sets;
  42
  43 @VisibleForTesting
  44 public class BGPSessionImpl extends AbstractProtocolSession<BGPMessage> implements BGPSession {
  45
  46         private static final Logger logger = LoggerFactory.getLogger(BGPSessionImpl.class);
  47
  48         private static final int DEFAULT_HOLD_TIMER_VALUE = 15;
  49
  50         public static int HOLD_TIMER_VALUE = DEFAULT_HOLD_TIMER_VALUE; // 240
  51
  52         /**
  53          * System.nanoTime value about when was sent the last message Protected to be updated also in tests.
  54          */
  55         protected long lastMessageSentAt;
  56
  57         /**
  58          * System.nanoTime value about when was received the last message
  59          */
  60         private long lastMessageReceivedAt;
  61
  62         private final BGPSessionListener listener;
  63
  64         /**
  65          * Timer object grouping FSM Timers
  66          */
  67         private final Timer stateTimer;
  68
  69         private final BGPSynchronization sync;
  70
  71         private int kaCounter = 0;
  72
  73         private final Channel channel;
  74
  75         @GuardedBy("this")
  76         private boolean closed = false;
  77
  78         private final short keepAlive;
  79
  80         private final Set<BGPTableType> tableTypes;
  81
  82         BGPSessionImpl(final Timer timer, final BGPSessionListener listener, final Channel channel, final short keepAlive,
  83                         final BGPOpenMessage remoteOpen) {
  84                 this.listener = Preconditions.checkNotNull(listener);
  85                 this.stateTimer = Preconditions.checkNotNull(timer);
  86                 this.channel = Preconditions.checkNotNull(channel);
  87                 this.keepAlive = keepAlive;
  88
  89                 final Set<BGPTableType> tts = Sets.newHashSet();
  90                 if (remoteOpen.getOptParams() != null) {
  91                         for (final BGPParameter param : remoteOpen.getOptParams()) {
  92                                 if (param instanceof MultiprotocolCapability) {
  93                                         tts.add(((MultiprotocolCapability) param).getTableType());
  94                                 }
  95                         }
  96                 }
  97
  98                 this.sync = new BGPSynchronization(this, this.listener, tts);
  99                 this.tableTypes = tts;
 100
 101                 if (remoteOpen.getHoldTime() != 0) {
 102                         this.stateTimer.newTimeout(new TimerTask() {
 103
 104                                 @Override
 105                                 public void run(final Timeout timeout) throws Exception {
 106                                         handleHoldTimer();
 107                                 }
 108                         }, remoteOpen.getHoldTime(), TimeUnit.SECONDS);
 109
 110                         this.stateTimer.newTimeout(new TimerTask() {
 111                                 @Override
 112                                 public void run(final Timeout timeout) throws Exception {
 113                                         handleKeepaliveTimer();
 114                                 }
 115                         }, keepAlive, TimeUnit.SECONDS);
 116                 }
 117         }
 118
 119         @Override
 120         public synchronized void close() {
 121                 logger.debug("Closing session: {}", this);
 122                 if (!this.closed) {
 123                         this.sendMessage(new BGPNotificationMessage(BGPError.CEASE));
 124                         this.channel.close();
 125                         this.closed = true;
 126                 }
 127         }
 128
 129         /**
 130          * Handles incoming message based on their type.
 131          *
 132          * @param msg incoming message
 133          */
 134         @Override
 135         public void handleMessage(final BGPMessage msg) {
 136                 // Update last reception time
 137                 this.lastMessageReceivedAt = System.nanoTime();
 138
 139                 if (msg instanceof BGPOpenMessage) {
 140                         // Open messages should not be present here
 141                         this.terminate(BGPError.FSM_ERROR);
 142                 } else if (msg instanceof BGPNotificationMessage) {
 143                         // Notifications are handled internally
 144                         logger.info("Session closed because Notification message received: {}", ((BGPNotificationMessage) msg).getError());
 145                         this.closeWithoutMessage();
 146                         this.listener.onSessionTerminated(this, new BGPTerminationReason(((BGPNotificationMessage) msg).getError()));
 147                 } else if (msg instanceof BGPKeepAliveMessage) {
 148                         // Keepalives are handled internally
 149                         logger.debug("Received KeepAlive messsage.");
 150                         this.kaCounter++;
 151                         if (this.kaCounter >= 2) {
 152                                 this.sync.kaReceived();
 153                         }
 154                 } else {
 155                         // All others are passed up
 156                         this.listener.onMessage(this, msg);
 157                 }
 158         }
 159
 160         @Override
 161         public synchronized void endOfInput() {
 162                 if (!this.closed) {
 163                         this.listener.onSessionDown(this, new IOException("End of input detected. Close the session."));
 164                 }
 165         }
 166
 167         void sendMessage(final BGPMessage msg) {
 168                 try {
 169                         this.channel.writeAndFlush(msg);
 170                         this.lastMessageSentAt = System.nanoTime();
 171                         logger.debug("Sent message: {}", msg);
 172                 } catch (final Exception e) {
 173                         logger.warn("Message {} was not sent.", msg, e);
 174                 }
 175         }
 176
 177         private synchronized void closeWithoutMessage() {
 178                 logger.debug("Closing session: {}", this);
 179                 this.channel.close();
 180                 this.closed = true;
 181         }
 182
 183         /**
 184          * Closes PCEP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 185          * modified, because he initiated the closing. (To prevent concurrent modification exception).
 186          *
 187          * @param closeObject
 188          */
 189         private void terminate(final BGPError error) {
 190                 this.sendMessage(new BGPNotificationMessage(error));
 191                 this.closeWithoutMessage();
 192                 this.listener.onSessionTerminated(this, new BGPTerminationReason(error));
 193         }
 194
 195         /**
 196          * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 197          * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 198          * which the message was received. If the session was closed by the time this method starts to execute (the session
 199          * state will become IDLE), then rescheduling won't occur.
 200          */
 201         private synchronized void handleHoldTimer() {
 202                 final long ct = System.nanoTime();
 203
 204                 final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(HOLD_TIMER_VALUE);
 205
 206                 if (!this.closed) {
 207                         if (ct >= nextHold) {
 208                                 logger.debug("HoldTimer expired. " + new Date());
 209                                 this.terminate(BGPError.HOLD_TIMER_EXPIRED);
 210                         } else {
 211                                 this.stateTimer.newTimeout(new TimerTask() {
 212                                         @Override
 213                                         public void run(final Timeout timeout) throws Exception {
 214                                                 handleHoldTimer();
 215                                         }
 216                                 }, nextHold - ct, TimeUnit.NANOSECONDS);
 217                         }
 218                 }
 219         }
 220
 221         /**
 222          * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 223          * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 224          * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 225          * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 226          */
 227         private synchronized void handleKeepaliveTimer() {
 228                 final long ct = System.nanoTime();
 229
 230                 long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 231
 232                 if (!this.closed) {
 233                         if (ct >= nextKeepalive) {
 234                                 this.sendMessage(new BGPKeepAliveMessage());
 235                                 nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 236                         }
 237                         this.stateTimer.newTimeout(new TimerTask() {
 238                                 @Override
 239                                 public void run(final Timeout timeout) throws Exception {
 240                                         handleKeepaliveTimer();
 241                                 }
 242                         }, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 243                 }
 244         }
 245
 246         @Override
 247         final public String toString() {
 248                 return addToStringAttributes(Objects.toStringHelper(this)).toString();
 249         }
 250
 251         protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 252                 toStringHelper.add("channel", this.channel);
 253                 toStringHelper.add("closed", this.closed);
 254                 return toStringHelper;
 255         }
 256
 257         @Override
 258         public Set<BGPTableType> getAdvertisedTableTypes() {
 259                 return this.tableTypes;
 260         }
 261
 262         @Override
 263         protected void sessionUp() {
 264                 this.listener.onSessionUp(this);
 265         }
 266 }