bgp/rib-impl/src/main/java/org/opendaylight/protocol/bgp/rib/impl/BGPPeer.java

   1 /*
   2  * Copyright (c) 2014 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 static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.base.MoreObjects;
  13 import com.google.common.base.MoreObjects.ToStringHelper;
  14 import com.google.common.base.Objects;
  15 import com.google.common.collect.ImmutableMap;
  16 import com.google.common.net.InetAddresses;
  17 import com.google.common.util.concurrent.Futures;
  18 import com.google.common.util.concurrent.ListenableFuture;
  19 import java.util.ArrayList;
  20 import java.util.Arrays;
  21 import java.util.Collections;
  22 import java.util.HashMap;
  23 import java.util.HashSet;
  24 import java.util.List;
  25 import java.util.Map;
  26 import java.util.Optional;
  27 import java.util.Set;
  28 import java.util.stream.Collectors;
  29 import javax.annotation.concurrent.GuardedBy;
  30 import org.opendaylight.controller.md.sal.common.api.data.AsyncTransaction;
  31 import org.opendaylight.controller.md.sal.common.api.data.TransactionChain;
  32 import org.opendaylight.controller.md.sal.common.api.data.TransactionChainListener;
  33 import org.opendaylight.controller.md.sal.dom.api.DOMTransactionChain;
  34 import org.opendaylight.controller.sal.binding.api.BindingAwareBroker.RoutedRpcRegistration;
  35 import org.opendaylight.controller.sal.binding.api.RpcProviderRegistry;
  36 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  37 import org.opendaylight.protocol.bgp.parser.BGPError;
  38 import org.opendaylight.protocol.bgp.parser.impl.message.update.LocalPreferenceAttributeParser;
  39 import org.opendaylight.protocol.bgp.parser.spi.MessageUtil;
  40 import org.opendaylight.protocol.bgp.rib.impl.spi.RIB;
  41 import org.opendaylight.protocol.bgp.rib.impl.spi.RIBSupportContext;
  42 import org.opendaylight.protocol.bgp.rib.impl.state.BGPPeerStateImpl;
  43 import org.opendaylight.protocol.bgp.rib.impl.state.BGPSessionStateProvider;
  44 import org.opendaylight.protocol.bgp.rib.spi.BGPSession;
  45 import org.opendaylight.protocol.bgp.rib.spi.BGPSessionListener;
  46 import org.opendaylight.protocol.bgp.rib.spi.BGPTerminationReason;
  47 import org.opendaylight.protocol.bgp.rib.spi.ExportPolicyPeerTracker;
  48 import org.opendaylight.protocol.bgp.rib.spi.IdentifierUtils;
  49 import org.opendaylight.protocol.bgp.rib.spi.Peer;
  50 import org.opendaylight.protocol.bgp.rib.spi.RouterIds;
  51 import org.opendaylight.protocol.bgp.rib.spi.state.BGPAfiSafiState;
  52 import org.opendaylight.protocol.bgp.rib.spi.state.BGPErrorHandlingState;
  53 import org.opendaylight.protocol.bgp.rib.spi.state.BGPSessionState;
  54 import org.opendaylight.protocol.bgp.rib.spi.state.BGPTimersState;
  55 import org.opendaylight.protocol.bgp.rib.spi.state.BGPTransportState;
  56 import org.opendaylight.protocol.concepts.AbstractRegistration;
  57 import org.opendaylight.protocol.util.Ipv4Util;
  58 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IpAddress;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.inet.rev171207.ipv4.prefixes.DestinationIpv4Builder;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.inet.rev171207.ipv4.prefixes.destination.ipv4.Ipv4Prefixes;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.inet.rev171207.ipv4.prefixes.destination.ipv4.Ipv4PrefixesBuilder;
  62 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.inet.rev171207.update.attributes.mp.reach.nlri.advertized.routes.destination.type.DestinationIpv4CaseBuilder;
  63 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.Update;
  64 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.path.attributes.Attributes;
  65 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.path.attributes.AttributesBuilder;
  66 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.update.message.Nlri;
  67 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.BgpAddPathTableType;
  68 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.BgpTableType;
  69 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.RouteRefresh;
  70 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.SendReceive;
  71 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.mp.capabilities.add.path.capability.AddressFamilies;
  72 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.MpReachNlri;
  73 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.MpReachNlriBuilder;
  74 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.MpUnreachNlri;
  75 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.MpUnreachNlriBuilder;
  76 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.mp.reach.nlri.AdvertizedRoutesBuilder;
  77 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.mp.unreach.nlri.WithdrawnRoutesBuilder;
  78 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.peer.rpc.rev171207.BgpPeerRpcService;
  79 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.peer.rpc.rev171207.PeerContext;
  80 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.PeerId;
  81 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.PeerRole;
  82 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.bgp.rib.rib.PeerKey;
  83 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.rib.TablesKey;
  84 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.AddressFamily;
  85 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.Ipv4AddressFamily;
  86 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.SubsequentAddressFamily;
  87 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.UnicastSubsequentAddressFamily;
  88 import org.opendaylight.yangtools.yang.binding.KeyedInstanceIdentifier;
  89 import org.opendaylight.yangtools.yang.binding.Notification;
  90 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  91 import org.slf4j.Logger;
  92 import org.slf4j.LoggerFactory;
  93
  94 /**
  95  * Class representing a peer. We have a single instance for each peer, which provides translation from BGP events into
  96  * RIB actions.
  97  */
  98 public class BGPPeer extends BGPPeerStateImpl implements BGPSessionListener, Peer, TransactionChainListener {
  99     private static final Logger LOG = LoggerFactory.getLogger(BGPPeer.class);
 100
 101     @GuardedBy("this")
 102     private final Set<TablesKey> tables = new HashSet<>();
 103     private final RIB rib;
 104     private final String name;
 105     private final Map<TablesKey, AdjRibOutListener> adjRibOutListenerSet = new HashMap<>();
 106     private final RpcProviderRegistry rpcRegistry;
 107     private final PeerRole peerRole;
 108     @GuardedBy("this")
 109     private AbstractRegistration trackerRegistration;
 110     @GuardedBy("this")
 111     private final Set<AbstractRegistration> tableRegistration = new HashSet<>();
 112     private final PeerId peerId;
 113     private final YangInstanceIdentifier peerIId;
 114     @GuardedBy("this")
 115     private BGPSession session;
 116     @GuardedBy("this")
 117     private byte[] rawIdentifier;
 118     @GuardedBy("this")
 119     private DOMTransactionChain chain;
 120     @GuardedBy("this")
 121     private AdjRibInWriter ribWriter;
 122     @GuardedBy("this")
 123     private EffectiveRibInWriter effRibInWriter;
 124     private RoutedRpcRegistration<BgpPeerRpcService> rpcRegistration;
 125     private Map<TablesKey, SendReceive> addPathTableMaps = Collections.emptyMap();
 126
 127     public BGPPeer(final IpAddress neighborAddress, final RIB rib, final PeerRole role,
 128             final RpcProviderRegistry rpcRegistry,
 129             final Set<TablesKey> afiSafisAdvertized,
 130             final Set<TablesKey> afiSafisGracefulAdvertized) {
 131         //FIXME BUG-6971 Once Peer Group is implemented, pass it
 132         super(rib.getInstanceIdentifier(), null, neighborAddress, afiSafisAdvertized,
 133                 afiSafisGracefulAdvertized);
 134         this.peerRole = role;
 135         this.rib = requireNonNull(rib);
 136         this.name = Ipv4Util.toStringIP(neighborAddress);
 137         this.rpcRegistry = rpcRegistry;
 138         this.peerId = RouterIds.createPeerId(neighborAddress);
 139         this.peerIId = this.rib.getYangRibId().node(org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang
 140                 .bgp.rib.rev171207.bgp.rib.rib.Peer.QNAME).node(IdentifierUtils.domPeerId(this.peerId));
 141         this.chain = rib.createPeerChain(this);
 142     }
 143
 144     private static Attributes nextHopToAttribute(final Attributes attrs, final MpReachNlri mpReach) {
 145         if (attrs.getCNextHop() == null && mpReach.getCNextHop() != null) {
 146             final AttributesBuilder attributesBuilder = new AttributesBuilder(attrs);
 147             attributesBuilder.setCNextHop(mpReach.getCNextHop());
 148             return attributesBuilder.build();
 149         }
 150         return attrs;
 151     }
 152
 153     /**
 154      * Creates MPReach for the prefixes to be handled in the same way as linkstate routes.
 155      *
 156      * @param message Update message containing prefixes in NLRI
 157      * @return MpReachNlri with prefixes from the nlri field
 158      */
 159     private static MpReachNlri prefixesToMpReach(final Update message) {
 160         final List<Ipv4Prefixes> prefixes = message.getNlri().stream()
 161                 .map(n -> new Ipv4PrefixesBuilder().setPrefix(n.getPrefix()).setPathId(n.getPathId()).build())
 162                 .collect(Collectors.toList());
 163         final MpReachNlriBuilder b = new MpReachNlriBuilder().setAfi(Ipv4AddressFamily.class).setSafi(
 164                 UnicastSubsequentAddressFamily.class).setAdvertizedRoutes(
 165                 new AdvertizedRoutesBuilder().setDestinationType(
 166                         new DestinationIpv4CaseBuilder().setDestinationIpv4(
 167                                 new DestinationIpv4Builder().setIpv4Prefixes(prefixes).build()).build()).build());
 168         if (message.getAttributes() != null) {
 169             b.setCNextHop(message.getAttributes().getCNextHop());
 170         }
 171         return b.build();
 172     }
 173
 174     /**
 175      * Create MPUnreach for the prefixes to be handled in the same way as linkstate routes.
 176      *
 177      * @param message            Update message containing withdrawn routes
 178      * @param isAnyNlriAnnounced isAnyNlriAnnounced
 179      * @return MpUnreachNlri with prefixes from the withdrawn routes field
 180      */
 181     private static MpUnreachNlri prefixesToMpUnreach(final Update message, final boolean isAnyNlriAnnounced) {
 182         final List<Ipv4Prefixes> prefixes = new ArrayList<>();
 183         message.getWithdrawnRoutes().forEach(w -> {
 184
 185             Optional<Nlri> nlriAnounced = Optional.empty();
 186             if (isAnyNlriAnnounced) {
 187                 nlriAnounced = message.getNlri().stream().filter(n -> Objects.equal(n.getPrefix(), w.getPrefix())
 188                         && Objects.equal(n.getPathId(), w.getPathId()))
 189                         .findAny();
 190             }
 191             if (!nlriAnounced.isPresent()) {
 192                 prefixes.add(new Ipv4PrefixesBuilder().setPrefix(w.getPrefix()).setPathId(w.getPathId()).build());
 193             }
 194         });
 195         return new MpUnreachNlriBuilder().setAfi(Ipv4AddressFamily.class).setSafi(UnicastSubsequentAddressFamily.class)
 196                 .setWithdrawnRoutes(new WithdrawnRoutesBuilder().setDestinationType(new org.opendaylight.yang.gen.v1
 197                         .urn.opendaylight.params.xml.ns.yang.bgp.inet.rev171207.update.attributes.mp.unreach.nlri
 198                         .withdrawn.routes.destination.type.DestinationIpv4CaseBuilder().setDestinationIpv4(
 199                         new DestinationIpv4Builder().setIpv4Prefixes(prefixes).build()).build()).build()).build();
 200     }
 201
 202     private static Map<TablesKey, SendReceive> mapTableTypesFamilies(final List<AddressFamilies> addPathTablesType) {
 203         return ImmutableMap.copyOf(addPathTablesType.stream().collect(Collectors.toMap(af -> new TablesKey(af.getAfi(),
 204                         af.getSafi()),
 205                 BgpAddPathTableType::getSendReceive)));
 206     }
 207
 208     public synchronized void instantiateServiceInstance() {
 209         this.ribWriter = AdjRibInWriter.create(this.rib.getYangRibId(), this.peerRole, this.chain);
 210         setActive(true);
 211     }
 212
 213     // FIXME ListenableFuture<?> should be used once closeServiceInstance uses wildcard too
 214     @Override
 215     public synchronized ListenableFuture<Void> close() {
 216         final ListenableFuture<Void> future = releaseConnection();
 217         this.chain.close();
 218         setActive(false);
 219         return future;
 220     }
 221
 222     @Override
 223     public void onMessage(final BGPSession session, final Notification msg) throws BGPDocumentedException {
 224         if (!(msg instanceof Update) && !(msg instanceof RouteRefresh)) {
 225             LOG.info("Ignoring unhandled message class {}", msg.getClass());
 226             return;
 227         }
 228         if (msg instanceof Update) {
 229             onUpdateMessage((Update) msg);
 230         } else {
 231             onRouteRefreshMessage((RouteRefresh) msg);
 232         }
 233     }
 234
 235     private void onRouteRefreshMessage(final RouteRefresh message) {
 236         final Class<? extends AddressFamily> rrAfi = message.getAfi();
 237         final Class<? extends SubsequentAddressFamily> rrSafi = message.getSafi();
 238
 239         final TablesKey key = new TablesKey(rrAfi, rrSafi);
 240         final AdjRibOutListener listener = this.adjRibOutListenerSet.get(key);
 241         if (listener != null) {
 242             listener.close();
 243             this.adjRibOutListenerSet.remove(key);
 244             createAdjRibOutListener(key, listener.isMpSupported());
 245         } else {
 246             LOG.info("Ignoring RouteRefresh message. Afi/Safi is not supported: {}, {}.", rrAfi, rrSafi);
 247         }
 248     }
 249
 250     /**
 251      * Check for presence of well known mandatory attribute LOCAL_PREF in Update message.
 252      *
 253      * @param message Update message
 254      */
 255     private void checkMandatoryAttributesPresence(final Update message) throws BGPDocumentedException {
 256         if (MessageUtil.isAnyNlriPresent(message)) {
 257             final Attributes attrs = message.getAttributes();
 258             if (this.peerRole == PeerRole.Ibgp && (attrs == null || attrs.getLocalPref() == null)) {
 259                 throw new BGPDocumentedException(BGPError.MANDATORY_ATTR_MISSING_MSG + "LOCAL_PREF",
 260                         BGPError.WELL_KNOWN_ATTR_MISSING,
 261                         new byte[]{LocalPreferenceAttributeParser.TYPE});
 262             }
 263         }
 264     }
 265
 266     /**
 267      * Process Update message received.
 268      * Calls {@link #checkMandatoryAttributesPresence(Update)} to check for presence of mandatory attributes.
 269      *
 270      * @param message Update message
 271      */
 272     private synchronized void onUpdateMessage(final Update message) throws BGPDocumentedException {
 273         checkMandatoryAttributesPresence(message);
 274
 275         // update AdjRibs
 276         final Attributes attrs = message.getAttributes();
 277         MpReachNlri mpReach;
 278         final boolean isAnyNlriAnnounced = message.getNlri() != null;
 279         if (isAnyNlriAnnounced) {
 280             mpReach = prefixesToMpReach(message);
 281         } else {
 282             mpReach = MessageUtil.getMpReachNlri(attrs);
 283         }
 284         if (mpReach != null) {
 285             this.ribWriter.updateRoutes(mpReach, nextHopToAttribute(attrs, mpReach));
 286         }
 287         MpUnreachNlri mpUnreach;
 288         if (message.getWithdrawnRoutes() != null) {
 289             mpUnreach = prefixesToMpUnreach(message, isAnyNlriAnnounced);
 290         } else {
 291             mpUnreach = MessageUtil.getMpUnreachNlri(attrs);
 292         }
 293         if (mpUnreach != null) {
 294             this.ribWriter.removeRoutes(mpUnreach);
 295         }
 296     }
 297
 298     @Override
 299     public synchronized void onSessionUp(final BGPSession session) {
 300         this.session = session;
 301         if (this.session instanceof BGPSessionStateProvider) {
 302             ((BGPSessionStateProvider) this.session).registerMessagesCounter(this);
 303         }
 304         final List<AddressFamilies> addPathTablesType = session.getAdvertisedAddPathTableTypes();
 305         final Set<BgpTableType> advertizedTableTypes = session.getAdvertisedTableTypes();
 306         final List<BgpTableType> advertizedGracefulRestartTableTypes = session.getAdvertisedGracefulRestartTableTypes();
 307         LOG.info("Session with peer {} went up with tables {} and Add Path tables {}", this.name,
 308                 advertizedTableTypes, addPathTablesType);
 309         this.rawIdentifier = InetAddresses.forString(session.getBgpId().getValue()).getAddress();
 310         this.tables.addAll(advertizedTableTypes.stream().map(t -> new TablesKey(t.getAfi(), t.getSafi()))
 311                 .collect(Collectors.toList()));
 312
 313         setAdvertizedGracefulRestartTableTypes(advertizedGracefulRestartTableTypes.stream()
 314                 .map(t -> new TablesKey(t.getAfi(), t.getSafi())).collect(Collectors.toList()));
 315         this.addPathTableMaps = mapTableTypesFamilies(addPathTablesType);
 316
 317         for (final TablesKey key : this.tables) {
 318             createAdjRibOutListener(key, true);
 319         }
 320
 321         for(final TablesKey tablesKey :this.tables) {
 322             final ExportPolicyPeerTracker exportTracker = this.rib.getExportPolicyPeerTracker(tablesKey);
 323             if (exportTracker != null) {
 324                 this.tableRegistration.add(exportTracker.registerPeer(this.peerId, this.addPathTableMaps.get(tablesKey),
 325                         this.peerIId, this.peerRole));
 326             }
 327         }
 328         addBgp4Support();
 329
 330         this.effRibInWriter = EffectiveRibInWriter.create(this.rib, this.rib.createPeerChain(this),
 331                 this.peerIId, this.tables);
 332         registerPrefixesCounters(this.effRibInWriter, this.effRibInWriter);
 333         this.ribWriter = this.ribWriter.transform(this.peerId, this.rib.getRibSupportContext(), this.tables,
 334                 this.addPathTableMaps);
 335
 336         if (this.rpcRegistry != null) {
 337             this.rpcRegistration = this.rpcRegistry.addRoutedRpcImplementation(BgpPeerRpcService.class,
 338                     new BgpPeerRpc(this, session, this.tables));
 339             final KeyedInstanceIdentifier<org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib
 340                     .rev171207.bgp.rib.rib.Peer, PeerKey> path = this.rib.getInstanceIdentifier()
 341                     .child(org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.bgp.rib
 342                              .rib.Peer.class, new PeerKey(this.peerId));
 343             this.rpcRegistration.registerPath(PeerContext.class, path);
 344         }
 345         this.trackerRegistration = this.rib.getPeerTracker().registerPeer(this);
 346     }
 347
 348     //try to add a support for old-school BGP-4, if peer did not advertise IPv4-Unicast MP capability
 349     private void addBgp4Support() {
 350         final TablesKey key = new TablesKey(Ipv4AddressFamily.class, UnicastSubsequentAddressFamily.class);
 351         if (this.tables.add(key)) {
 352             createAdjRibOutListener(key, false);
 353             final ExportPolicyPeerTracker exportTracker = this.rib.getExportPolicyPeerTracker(key);
 354             if (exportTracker != null) {
 355                 this.tableRegistration.add(exportTracker.registerPeer(peerId,  null, this.peerIId,
 356                         this.peerRole));
 357             }
 358         }
 359     }
 360
 361     private synchronized void createAdjRibOutListener(final TablesKey key,
 362             final boolean mpSupport) {
 363         final RIBSupportContext context = this.rib.getRibSupportContext().getRIBSupportContext(key);
 364
 365         // not particularly nice
 366         if (context != null && this.session instanceof BGPSessionImpl) {
 367             final ChannelOutputLimiter limiter = ((BGPSessionImpl) this.session).getLimiter();
 368             final AdjRibOutListener adjRibOut = AdjRibOutListener.create(this.peerId, key,
 369                     this.rib.getYangRibId(), this.rib.getCodecsRegistry(), context.getRibSupport(),
 370                     this.rib.getService(), limiter, mpSupport);
 371             this.adjRibOutListenerSet.put(key, adjRibOut);
 372             registerPrefixesSentCounter(key, adjRibOut);
 373         }
 374     }
 375
 376     private ListenableFuture<Void> cleanup() {
 377         // FIXME: BUG-196: support graceful
 378         this.adjRibOutListenerSet.values().forEach(AdjRibOutListener::close);
 379         this.adjRibOutListenerSet.clear();
 380         if (this.effRibInWriter != null) {
 381             this.effRibInWriter.close();
 382         }
 383         this.tables.clear();
 384         if (this.ribWriter != null) {
 385             return this.ribWriter.removePeer();
 386         }
 387         return Futures.immediateFuture(null);
 388     }
 389
 390     @Override
 391     public void onSessionDown(final BGPSession session, final Exception e) {
 392         if (e.getMessage().equals(BGPSessionImpl.END_OF_INPUT)) {
 393             LOG.info("Session with peer {} went down", this.name);
 394         } else {
 395             LOG.info("Session with peer {} went down", this.name, e);
 396         }
 397         releaseConnection();
 398     }
 399
 400     @Override
 401     public void onSessionTerminated(final BGPSession session, final BGPTerminationReason cause) {
 402         LOG.info("Session with peer {} terminated: {}", this.name, cause);
 403         releaseConnection();
 404     }
 405
 406     @Override
 407     public String toString() {
 408         return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
 409     }
 410
 411     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 412         toStringHelper.add("name", this.name);
 413         toStringHelper.add("tables", this.tables);
 414         return toStringHelper;
 415     }
 416
 417     @Override
 418     public String getName() {
 419         return this.name;
 420     }
 421
 422     @Override
 423     public synchronized ListenableFuture<Void> releaseConnection() {
 424         if (this.rpcRegistration != null) {
 425             this.rpcRegistration.close();
 426         }
 427         closeRegistration();
 428         final ListenableFuture<Void> future = cleanup();
 429
 430         if (this.session != null) {
 431             try {
 432                 this.session.close();
 433             } catch (final Exception e) {
 434                 LOG.warn("Error closing session with peer", e);
 435             }
 436             this.session = null;
 437         }
 438
 439         resetState();
 440         return future;
 441     }
 442
 443     private void closeRegistration() {
 444         this.tableRegistration.iterator().forEachRemaining(AbstractRegistration::close);
 445         this.tableRegistration.clear();
 446         if (this.trackerRegistration != null) {
 447             this.trackerRegistration.close();
 448             this.trackerRegistration = null;
 449         }
 450     }
 451
 452     @Override
 453     public synchronized byte[] getRawIdentifier() {
 454         return Arrays.copyOf(this.rawIdentifier, this.rawIdentifier.length);
 455     }
 456
 457     @Override
 458     public PeerId getPeerId() {
 459         return this.peerId;
 460     }
 461
 462     @Override
 463     public SendReceive getSupportedAddPathTables(final TablesKey tableKey) {
 464         return this.addPathTableMaps.get(tableKey);
 465     }
 466
 467     @Override
 468     public boolean supportsTable(final TablesKey tableKey) {
 469         return this.tables.contains(tableKey);
 470     }
 471
 472     @Override
 473     public YangInstanceIdentifier getPeerRibInstanceIdentifier() {
 474         return this.peerIId;
 475     }
 476
 477     @Override
 478     public PeerRole getRole() {
 479         return this.peerRole;
 480     }
 481
 482     @Override
 483     public synchronized void onTransactionChainFailed(final TransactionChain<?, ?> chain,
 484             final AsyncTransaction<?, ?> transaction, final Throwable cause) {
 485         LOG.error("Transaction chain failed.", cause);
 486         this.chain.close();
 487         this.chain = this.rib.createPeerChain(this);
 488         this.ribWriter = AdjRibInWriter.create(this.rib.getYangRibId(), this.peerRole, this.chain);
 489         releaseConnection();
 490     }
 491
 492     @Override
 493     public void onTransactionChainSuccessful(final TransactionChain<?, ?> chain) {
 494         LOG.debug("Transaction chain {} successful.", chain);
 495     }
 496
 497     @Override
 498     public synchronized void markUptodate(final TablesKey tablesKey) {
 499         this.ribWriter.markTableUptodate(tablesKey);
 500     }
 501
 502     @Override
 503     public BGPErrorHandlingState getBGPErrorHandlingState() {
 504         return this;
 505     }
 506
 507     @Override
 508     public BGPAfiSafiState getBGPAfiSafiState() {
 509         return this;
 510     }
 511
 512     @Override
 513     public synchronized BGPSessionState getBGPSessionState() {
 514         if (this.session instanceof BGPSessionStateProvider) {
 515             return ((BGPSessionStateProvider) this.session).getBGPSessionState();
 516         }
 517         return null;
 518     }
 519
 520     @Override
 521     public synchronized BGPTimersState getBGPTimersState() {
 522         if (this.session instanceof BGPSessionStateProvider) {
 523             return ((BGPSessionStateProvider) this.session).getBGPTimersState();
 524         }
 525         return null;
 526     }
 527
 528     @Override
 529     public synchronized BGPTransportState getBGPTransportState() {
 530         if (this.session instanceof BGPSessionStateProvider) {
 531             return ((BGPSessionStateProvider) this.session).getBGPTransportState();
 532         }
 533         return null;
 534     }
 535 }