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.rev130918.LinkstateAddressFamily;
  27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev130918.LinkstateSubsequentAddressFamily;
  28 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.Keepalive;
  29 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.KeepaliveBuilder;
  30 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.Notify;
  31 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.NotifyBuilder;
  32 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.Open;
  33 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.OpenBuilder;
  34 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.open.BgpParameters;
  35 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.open.bgp.parameters.CParameters;
  36 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130918.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         // FIXME to actual value
  47         protected static final int INITIAL_HOLDTIMER = 1;
  48
  49         @VisibleForTesting
  50         public enum State {
  51                 /**
  52                  * Negotiation has not started yet.
  53                  */
  54                 Idle,
  55                 /**
  56                  * We have sent our Open message, and are waiting for the peer's Open message.
  57                  */
  58                 OpenSent,
  59                 /**
  60                  * We have received the peer's Open message, which is acceptable, and we're waiting the acknowledgement of our
  61                  * Open message.
  62                  */
  63                 OpenConfirm,
  64                 /**
  65                  * The negotiation finished.
  66                  */
  67                 Finished,
  68         }
  69
  70         private static final Logger logger = LoggerFactory.getLogger(BGPSessionNegotiator.class);
  71         private final BGPSessionListener listener;
  72         private final Timer timer;
  73         private final BGPSessionPreferences localPref;
  74
  75         @GuardedBy("this")
  76         private Open remotePref;
  77
  78         @GuardedBy("this")
  79         private State state = State.Idle;
  80
  81         @GuardedBy("this")
  82         private BGPSessionImpl session;
  83
  84         public BGPSessionNegotiator(final Timer timer, final Promise<BGPSessionImpl> promise, final Channel channel,
  85                         final BGPSessionPreferences initialPrefs, final BGPSessionListener listener) {
  86                 super(promise, channel);
  87                 this.listener = Preconditions.checkNotNull(listener);
  88                 this.localPref = Preconditions.checkNotNull(initialPrefs);
  89                 this.timer = Preconditions.checkNotNull(timer);
  90         }
  91
  92         @Override
  93         protected void startNegotiation() {
  94                 Preconditions.checkState(this.state == State.Idle);
  95                 this.channel.writeAndFlush(new OpenBuilder().setMyAsNumber(this.localPref.getMyAs()).setHoldTimer(this.localPref.getHoldTime()).setBgpIdentifier(
  96                                 this.localPref.getBgpId()).setBgpParameters(this.localPref.getParams()).build());
  97                 this.state = State.OpenSent;
  98
  99                 final Object lock = this;
 100                 this.timer.newTimeout(new TimerTask() {
 101                         @Override
 102                         public void run(final Timeout timeout) throws Exception {
 103                                 synchronized (lock) {
 104                                         if (BGPSessionNegotiator.this.state != State.Finished) {
 105                                                 negotiationFailed(new BGPDocumentedException("HoldTimer expired", BGPError.FSM_ERROR));
 106                                                 BGPSessionNegotiator.this.channel.writeAndFlush(new NotifyBuilder().setErrorCode(
 107                                                                 BGPError.HOLD_TIMER_EXPIRED.getCode()).setErrorSubcode(BGPError.HOLD_TIMER_EXPIRED.getSubcode()).build());
 108                                                 BGPSessionNegotiator.this.state = State.Finished;
 109                                         }
 110                                 }
 111                         }
 112                 }, INITIAL_HOLDTIMER, TimeUnit.MINUTES);
 113         }
 114
 115         @Override
 116         protected synchronized void handleMessage(final Notification msg) {
 117                 logger.debug("Channel {} handling message in state {}", this.channel, this.state);
 118
 119                 switch (this.state) {
 120                 case Finished:
 121                 case Idle:
 122                         final Notify fsmError = new NotifyBuilder().setErrorCode(BGPError.FSM_ERROR.getCode()).setErrorSubcode(
 123                                         BGPError.FSM_ERROR.getSubcode()).build();
 124                         this.channel.writeAndFlush(fsmError);
 125                 case OpenConfirm:
 126                         if (msg instanceof Keepalive) {
 127                                 negotiationSuccessful(this.session);
 128                         } else if (msg instanceof Notify) {
 129                                 final Notify ntf = (Notify) msg;
 130                                 negotiationFailed(new BGPDocumentedException("Peer refusal", BGPError.forValue(ntf.getErrorCode(), ntf.getErrorSubcode())));
 131                         }
 132                         this.state = State.Finished;
 133                         return;
 134                 case OpenSent:
 135                         if (msg instanceof Open) {
 136                                 final Open openObj = (Open) msg;
 137                                 handleOpen(openObj);
 138                                 return;
 139                         }
 140                         break;
 141                 }
 142
 143                 // Catch-all for unexpected message
 144                 logger.warn("Channel {} state {} unexpected message {}", this.channel, this.state, msg);
 145                 this.channel.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.FSM_ERROR.getCode()).setErrorSubcode(
 146                                 BGPError.FSM_ERROR.getSubcode()).build());
 147                 negotiationFailed(new BGPDocumentedException("Unexpected message", BGPError.FSM_ERROR));
 148                 this.state = State.Finished;
 149         }
 150
 151         private void handleOpen(final Open openObj) {
 152                 final List<BgpParameters> prefs = openObj.getBgpParameters();
 153                 if (prefs != null && !prefs.isEmpty()) {
 154                         for (final BgpParameters param : openObj.getBgpParameters()) {
 155                                 final CParameters cap = param.getCParameters();
 156                                 // FIXME: the reference to linkstate should be moved to config subsystem!
 157
 158                                 if (cap instanceof CMultiprotocol
 159                                                 && ((CMultiprotocol) cap).getMultiprotocolCapability().getAfi() == LinkstateAddressFamily.class
 160                                                 && ((CMultiprotocol) cap).getMultiprotocolCapability().getSafi() == LinkstateSubsequentAddressFamily.class) {
 161                                         this.remotePref = openObj;
 162                                         this.channel.writeAndFlush(new KeepaliveBuilder().build());
 163                                         this.session = new BGPSessionImpl(this.timer, this.listener, this.channel, this.remotePref);
 164                                         this.state = State.OpenConfirm;
 165                                         logger.debug("Channel {} moved to OpenConfirm state with remote proposal {}", this.channel, this.remotePref);
 166                                         return;
 167                                 }
 168                         }
 169                 }
 170                 final Notify ntf = new NotifyBuilder().setErrorCode(BGPError.UNSPECIFIC_OPEN_ERROR.getCode()).setErrorSubcode(
 171                                 BGPError.UNSPECIFIC_OPEN_ERROR.getSubcode()).build();
 172                 this.channel.writeAndFlush(ntf);
 173                 negotiationFailed(new BGPDocumentedException("Linkstate capability is not configured on router. Check the configuration of BGP speaker.", BGPError.forValue(
 174                                 ntf.getErrorCode(), ntf.getErrorSubcode())));
 175                 this.state = State.Finished;
 176         }
 177
 178         public synchronized State getState() {
 179                 return this.state;
 180         }
 181 }