bgp/rib-impl/src/main/java/org/opendaylight/protocol/bgp/rib/impl/BGPSessionNegotiator.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 import io.netty.util.concurrent.Promise;
  15
  16 import java.util.List;
  17 import java.util.concurrent.TimeUnit;
  18
  19 import javax.annotation.concurrent.GuardedBy;
  20
  21 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  22 import org.opendaylight.protocol.bgp.parser.BGPError;
  23 import org.opendaylight.protocol.bgp.parser.BGPSessionListener;
  24 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  25 import org.opendaylight.protocol.framework.AbstractSessionNegotiator;
  26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev131125.LinkstateAddressFamily;
  27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev131125.LinkstateSubsequentAddressFamily;
  28 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Keepalive;
  29 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.KeepaliveBuilder;
  30 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Notify;
  31 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.NotifyBuilder;
  32 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Open;
  33 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.OpenBuilder;
  34 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.BgpParameters;
  35 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.bgp.parameters.CParameters;
  36 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.open.bgp.parameters.c.parameters.CMultiprotocol;
  37 import org.opendaylight.yangtools.yang.binding.Notification;
  38 import org.slf4j.Logger;
  39 import org.slf4j.LoggerFactory;
  40
  41 import com.google.common.annotations.VisibleForTesting;
  42 import com.google.common.base.Preconditions;
  43
  44 public final class BGPSessionNegotiator extends AbstractSessionNegotiator<Notification, BGPSessionImpl> {
  45         // 4 minutes recommended in http://tools.ietf.org/html/rfc4271#section-8.2.2
  46         protected static final int INITIAL_HOLDTIMER = 4;
  47
  48         @VisibleForTesting
  49         public enum State {
  50                 /**
  51                  * Negotiation has not started yet.
  52                  */
  53                 Idle,
  54                 /**
  55                  * We have sent our Open message, and are waiting for the peer's Open message.
  56                  */
  57                 OpenSent,
  58                 /**
  59                  * We have received the peer's Open message, which is acceptable, and we're waiting the acknowledgement of our
  60                  * Open message.
  61                  */
  62                 OpenConfirm,
  63                 /**
  64                  * The negotiation finished.
  65                  */
  66                 Finished,
  67         }
  68
  69         private static final Logger logger = LoggerFactory.getLogger(BGPSessionNegotiator.class);
  70         private final BGPSessionListener listener;
  71         private final Timer timer;
  72         private final BGPSessionPreferences localPref;
  73
  74         @GuardedBy("this")
  75         private Open remotePref;
  76
  77         @GuardedBy("this")
  78         private State state = State.Idle;
  79
  80         @GuardedBy("this")
  81         private BGPSessionImpl session;
  82
  83         public BGPSessionNegotiator(final Timer timer, final Promise<BGPSessionImpl> promise, final Channel channel,
  84                         final BGPSessionPreferences initialPrefs, final BGPSessionListener listener) {
  85                 super(promise, channel);
  86                 this.listener = Preconditions.checkNotNull(listener);
  87                 this.localPref = Preconditions.checkNotNull(initialPrefs);
  88                 this.timer = Preconditions.checkNotNull(timer);
  89         }
  90
  91         @Override
  92         protected void startNegotiation() {
  93                 Preconditions.checkState(this.state == State.Idle);
  94                 this.channel.writeAndFlush(new OpenBuilder().setMyAsNumber(this.localPref.getMyAs()).setHoldTimer(this.localPref.getHoldTime()).setBgpIdentifier(
  95                                 this.localPref.getBgpId()).setBgpParameters(this.localPref.getParams()).build());
  96                 this.state = State.OpenSent;
  97
  98                 final Object lock = this;
  99                 this.timer.newTimeout(new TimerTask() {
 100                         @Override
 101                         public void run(final Timeout timeout) throws Exception {
 102                                 synchronized (lock) {
 103                                         if (BGPSessionNegotiator.this.state != State.Finished) {
 104                                                 BGPSessionNegotiator.this.channel.writeAndFlush(new NotifyBuilder().setErrorCode(
 105                                                                 BGPError.HOLD_TIMER_EXPIRED.getCode()).setErrorSubcode(BGPError.HOLD_TIMER_EXPIRED.getSubcode()).build());
 106                                                 negotiationFailed(new BGPDocumentedException("HoldTimer expired", BGPError.FSM_ERROR));
 107                                                 BGPSessionNegotiator.this.state = State.Finished;
 108                                         }
 109                                 }
 110                         }
 111                 }, INITIAL_HOLDTIMER, TimeUnit.MINUTES);
 112         }
 113
 114         @Override
 115         protected synchronized void handleMessage(final Notification msg) {
 116                 logger.debug("Channel {} handling message in state {}", this.channel, this.state);
 117
 118                 switch (this.state) {
 119                 case Finished:
 120                 case Idle:
 121                         final Notify fsmError = new NotifyBuilder().setErrorCode(BGPError.FSM_ERROR.getCode()).setErrorSubcode(
 122                                         BGPError.FSM_ERROR.getSubcode()).build();
 123                         this.channel.writeAndFlush(fsmError);
 124                 case OpenConfirm:
 125                         if (msg instanceof Keepalive) {
 126                                 negotiationSuccessful(this.session);
 127                         } else if (msg instanceof Notify) {
 128                                 final Notify ntf = (Notify) msg;
 129                                 negotiationFailed(new BGPDocumentedException("Peer refusal", BGPError.forValue(ntf.getErrorCode(), ntf.getErrorSubcode())));
 130                         }
 131                         this.state = State.Finished;
 132                         return;
 133                 case OpenSent:
 134                         if (msg instanceof Open) {
 135                                 final Open openObj = (Open) msg;
 136                                 handleOpen(openObj);
 137                                 return;
 138                         }
 139                         break;
 140                 }
 141
 142                 // Catch-all for unexpected message
 143                 logger.warn("Channel {} state {} unexpected message {}", this.channel, this.state, msg);
 144                 this.channel.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.FSM_ERROR.getCode()).setErrorSubcode(
 145                                 BGPError.FSM_ERROR.getSubcode()).build());
 146                 negotiationFailed(new BGPDocumentedException("Unexpected message", BGPError.FSM_ERROR));
 147                 this.state = State.Finished;
 148         }
 149
 150         private void handleOpen(final Open openObj) {
 151                 final List<BgpParameters> prefs = openObj.getBgpParameters();
 152                 if (prefs != null && !prefs.isEmpty()) {
 153                         for (final BgpParameters param : openObj.getBgpParameters()) {
 154                                 final CParameters cap = param.getCParameters();
 155                                 // FIXME: the reference to linkstate should be moved to config subsystem!
 156
 157                                 if (cap instanceof CMultiprotocol
 158                                                 && ((CMultiprotocol) cap).getMultiprotocolCapability().getAfi() == LinkstateAddressFamily.class
 159                                                 && ((CMultiprotocol) cap).getMultiprotocolCapability().getSafi() == LinkstateSubsequentAddressFamily.class) {
 160                                         this.remotePref = openObj;
 161                                         this.channel.writeAndFlush(new KeepaliveBuilder().build());
 162                                         this.session = new BGPSessionImpl(this.timer, this.listener, this.channel, this.remotePref);
 163                                         this.state = State.OpenConfirm;
 164                                         logger.debug("Channel {} moved to OpenConfirm state with remote proposal {}", this.channel, this.remotePref);
 165                                         return;
 166                                 }
 167                         }
 168                 }
 169                 final Notify ntf = new NotifyBuilder().setErrorCode(BGPError.UNSPECIFIC_OPEN_ERROR.getCode()).setErrorSubcode(
 170                                 BGPError.UNSPECIFIC_OPEN_ERROR.getSubcode()).build();
 171                 this.channel.writeAndFlush(ntf);
 172                 negotiationFailed(new BGPDocumentedException("Linkstate capability is not configured on router. Check the configuration of BGP speaker.", BGPError.forValue(
 173                                 ntf.getErrorCode(), ntf.getErrorSubcode())));
 174                 this.state = State.Finished;
 175         }
 176
 177         public synchronized State getState() {
 178                 return this.state;
 179         }
 180 }