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

   1 /*
   2  * Copyright (c) 2016 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.config;
   9
  10 import static org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IetfInetUtil.INSTANCE;
  11
  12 import com.google.common.collect.ImmutableList;
  13 import java.util.ArrayList;
  14 import java.util.Collections;
  15 import java.util.HashMap;
  16 import java.util.List;
  17 import java.util.Map;
  18 import java.util.Optional;
  19 import java.util.Set;
  20 import java.util.stream.Collectors;
  21 import org.eclipse.jdt.annotation.NonNull;
  22 import org.eclipse.jdt.annotation.Nullable;
  23 import org.opendaylight.protocol.bgp.mode.api.PathSelectionMode;
  24 import org.opendaylight.protocol.bgp.mode.impl.add.all.paths.AllPathSelection;
  25 import org.opendaylight.protocol.bgp.mode.impl.add.n.paths.AddPathBestNPathSelection;
  26 import org.opendaylight.protocol.bgp.openconfig.spi.BGPTableTypeRegistryConsumer;
  27 import org.opendaylight.protocol.bgp.parser.spi.RevisedErrorHandlingSupport;
  28 import org.opendaylight.protocol.bgp.parser.spi.pojo.RevisedErrorHandlingSupportImpl;
  29 import org.opendaylight.protocol.concepts.KeyMapping;
  30 import org.opendaylight.protocol.util.Ipv4Util;
  31 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.multiprotocol.rev151009.BgpCommonAfiSafiList;
  32 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.multiprotocol.rev151009.bgp.common.afi.safi.list.AfiSafi;
  33 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.multiprotocol.rev151009.bgp.common.afi.safi.list.AfiSafiBuilder;
  34 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.BgpNeighborAddPathsConfig;
  35 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.BgpNeighborGroup;
  36 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.BgpNeighborTransportConfig;
  37 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.graceful.restart.GracefulRestart;
  38 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.ErrorHandling;
  39 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.RouteReflector;
  40 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.Timers;
  41 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.Transport;
  42 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.transport.Config;
  43 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbors.Neighbor;
  44 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbors.NeighborKey;
  45 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.peer.group.PeerGroup;
  46 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.top.Bgp;
  47 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.top.bgp.Neighbors;
  48 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.types.rev151009.IPV4UNICAST;
  49 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.types.rev151009.PeerType;
  50 import org.opendaylight.yang.gen.v1.http.openconfig.net.yang.network.instance.rev151018.network.instance.top.network.instances.network.instance.protocols.Protocol;
  51 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.AsNumber;
  52 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IpAddress;
  53 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.PortNumber;
  54 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.BgpTableType;
  55 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.SendReceive;
  56 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.mp.capabilities.add.path.capability.AddressFamilies;
  57 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.mp.capabilities.add.path.capability.AddressFamiliesBuilder;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.openconfig.extensions.rev180329.GlobalAddPathsConfig;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.openconfig.extensions.rev180329.GlobalConfigAugmentation;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.openconfig.extensions.rev180329.NeighborAddPathsConfig;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.openconfig.extensions.rev180329.NeighborPeerGroupConfig;
  62 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.openconfig.extensions.rev180329.NeighborTransportConfig;
  63 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.openconfig.extensions.rev180329.PeerGroupTransportConfig;
  64 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.openconfig.extensions.rev180329.TransportConfig;
  65 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev180329.PeerRole;
  66 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev180329.rib.TablesKey;
  67 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev180329.ClusterIdentifier;
  68 import org.opendaylight.yangtools.yang.binding.Augmentation;
  69 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  70 import org.opendaylight.yangtools.yang.common.Uint16;
  71
  72 final class OpenConfigMappingUtil {
  73
  74     static final String APPLICATION_PEER_GROUP_NAME = "application-peers";
  75     static final Optional<String> APPLICATION_PEER_GROUP_NAME_OPT = Optional.of(APPLICATION_PEER_GROUP_NAME);
  76     static final int HOLDTIMER = 90;
  77     private static final AfiSafi IPV4_AFISAFI = new AfiSafiBuilder().setAfiSafiName(IPV4UNICAST.class).build();
  78     private static final List<AfiSafi> DEFAULT_AFISAFI = ImmutableList.of(IPV4_AFISAFI);
  79     private static final int CONNECT_RETRY = 30;
  80     private static final PortNumber PORT = new PortNumber(179);
  81
  82     private OpenConfigMappingUtil() {
  83         throw new UnsupportedOperationException();
  84     }
  85
  86     static String getRibInstanceName(final InstanceIdentifier<?> rootIdentifier) {
  87         return rootIdentifier.firstKeyOf(Protocol.class).getName();
  88     }
  89
  90     static KeyMapping getNeighborKey(final Neighbor neighbor) {
  91         if (neighbor.getConfig() != null) {
  92             final String authPassword = neighbor.getConfig().getAuthPassword();
  93             if (authPassword != null) {
  94                 return KeyMapping.getKeyMapping(INSTANCE.inetAddressFor(neighbor.getNeighborAddress()), authPassword);
  95             }
  96         }
  97         return null;
  98     }
  99
 100     static InstanceIdentifier<Neighbor> getNeighborInstanceIdentifier(
 101             final InstanceIdentifier<Bgp> rootIdentifier,
 102             final NeighborKey neighborKey) {
 103         return rootIdentifier.child(Neighbors.class).child(Neighbor.class, neighborKey);
 104     }
 105
 106     static String getNeighborInstanceName(final InstanceIdentifier<?> rootIdentifier) {
 107         return Ipv4Util.toStringIP(rootIdentifier.firstKeyOf(Neighbor.class).getNeighborAddress());
 108     }
 109
 110     //make sure IPv4 Unicast (RFC 4271) when required
 111     static List<AfiSafi> getAfiSafiWithDefault(
 112             final BgpCommonAfiSafiList afiSAfis, final boolean setDeafultIPv4) {
 113         if (afiSAfis == null || afiSAfis.getAfiSafi() == null) {
 114             return setDeafultIPv4 ? DEFAULT_AFISAFI : Collections.emptyList();
 115         }
 116         final List<AfiSafi> afiSafi = afiSAfis.getAfiSafi();
 117         if (setDeafultIPv4) {
 118             final boolean anyMatch = afiSafi.stream()
 119                     .anyMatch(input -> input.getAfiSafiName().equals(IPV4UNICAST.class));
 120             if (!anyMatch) {
 121                 final List<AfiSafi> newAfiSafi = new ArrayList<>(afiSafi.size() + 1);
 122                 newAfiSafi.addAll(afiSafi);
 123                 newAfiSafi.add(IPV4_AFISAFI);
 124                 return newAfiSafi;
 125             }
 126         }
 127         return afiSafi;
 128     }
 129
 130     static ClusterIdentifier getGlobalClusterIdentifier(final org.opendaylight.yang.gen.v1.http.openconfig.net
 131             .yang.bgp.rev151009.bgp.global.base.Config globalConfig) {
 132         final GlobalConfigAugmentation globalConfigAugmentation
 133                 = globalConfig.augmentation(GlobalConfigAugmentation.class);
 134         if (globalConfigAugmentation != null && globalConfigAugmentation.getRouteReflectorClusterId() != null) {
 135             return new ClusterIdentifier(globalConfigAugmentation.getRouteReflectorClusterId().getIpv4Address());
 136         }
 137         return new ClusterIdentifier(globalConfig.getRouterId());
 138     }
 139
 140     static @Nullable ClusterIdentifier getNeighborClusterIdentifier(
 141             final @Nullable RouteReflector routeReflector, final @Nullable PeerGroup peerGroup) {
 142         if (peerGroup != null) {
 143             final ClusterIdentifier clusteriId = extractClusterId(peerGroup.getRouteReflector());
 144             if (clusteriId != null) {
 145                 return clusteriId;
 146             }
 147         }
 148
 149         return extractClusterId(routeReflector);
 150     }
 151
 152     private static ClusterIdentifier extractClusterId(final RouteReflector routeReflector) {
 153         if (routeReflector != null) {
 154             final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.route
 155                     .reflector.Config config = routeReflector.getConfig();
 156             if (config != null && config.getRouteReflectorClusterId() != null) {
 157                 return new ClusterIdentifier(config.getRouteReflectorClusterId().getIpv4Address());
 158             }
 159         }
 160         return null;
 161     }
 162
 163     static Map<BgpTableType, PathSelectionMode> toPathSelectionMode(final List<AfiSafi> afiSafis,
 164             final BGPTableTypeRegistryConsumer tableTypeRegistry) {
 165         final Map<BgpTableType, PathSelectionMode> pathSelectionModes = new HashMap<>();
 166         for (final AfiSafi afiSafi : afiSafis) {
 167             final BgpNeighborAddPathsConfig afiSafi2 = afiSafi.augmentation(GlobalAddPathsConfig.class);
 168             if (afiSafi2 != null) {
 169                 final Optional<BgpTableType> bgpTableType = tableTypeRegistry.getTableType(afiSafi.getAfiSafiName());
 170                 if (bgpTableType.isPresent()) {
 171                     final short sendMax = afiSafi2.getSendMax().toJava();
 172                     final PathSelectionMode selectionMode;
 173                     if (sendMax > 1) {
 174                         selectionMode = new AddPathBestNPathSelection(sendMax);
 175                     } else {
 176                         selectionMode = new AllPathSelection();
 177                     }
 178                     pathSelectionModes.put(bgpTableType.get(), selectionMode);
 179                 }
 180             }
 181         }
 182         return pathSelectionModes;
 183     }
 184
 185     static boolean isApplicationPeer(final Neighbor neighbor) {
 186         final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group
 187                 .Config config = neighbor.getConfig();
 188         if (config != null) {
 189             final NeighborPeerGroupConfig config1 = config.augmentation(NeighborPeerGroupConfig.class);
 190             if (config1 != null) {
 191                 final String peerGroup = config1.getPeerGroup();
 192                 return peerGroup != null && peerGroup.equals(APPLICATION_PEER_GROUP_NAME);
 193             }
 194         }
 195         return false;
 196     }
 197
 198     static List<AddressFamilies> toAddPathCapability(final List<AfiSafi> afiSafis,
 199             final BGPTableTypeRegistryConsumer tableTypeRegistry) {
 200         final List<AddressFamilies> addPathCapability = new ArrayList<>();
 201         for (final AfiSafi afiSafi : afiSafis) {
 202             final BgpNeighborAddPathsConfig afiSafi1 = afiSafi.augmentation(NeighborAddPathsConfig.class);
 203             final Optional<BgpTableType> bgpTableType = tableTypeRegistry.getTableType(afiSafi.getAfiSafiName());
 204             if (afiSafi1 != null && bgpTableType.isPresent()) {
 205                 final AddressFamiliesBuilder builder = new AddressFamiliesBuilder(bgpTableType.get());
 206                 builder.setSendReceive(toSendReceiveMode(afiSafi1));
 207                 addPathCapability.add(builder.build());
 208             }
 209         }
 210         return addPathCapability;
 211     }
 212
 213     private static SendReceive toSendReceiveMode(final BgpNeighborAddPathsConfig addPath) {
 214         if (addPath.isReceive() && addPath.getSendMax() != null) {
 215             return SendReceive.Both;
 216         }
 217         if (addPath.getSendMax() != null) {
 218             return SendReceive.Send;
 219         }
 220         return SendReceive.Receive;
 221     }
 222
 223     private static boolean isRrClient(final BgpNeighborGroup neighbor) {
 224         final RouteReflector routeReflector = neighbor.getRouteReflector();
 225         if (routeReflector != null && routeReflector.getConfig() != null) {
 226             return routeReflector.getConfig().isRouteReflectorClient();
 227         }
 228         return false;
 229     }
 230
 231     static List<BgpTableType> toTableTypes(final List<AfiSafi> afiSafis,
 232             final BGPTableTypeRegistryConsumer tableTypeRegistry) {
 233         return afiSafis.stream()
 234                 .map(afiSafi -> tableTypeRegistry.getTableType(afiSafi.getAfiSafiName()))
 235                 .filter(Optional::isPresent)
 236                 .map(Optional::get)
 237                 .collect(Collectors.toList());
 238     }
 239
 240     static Set<TablesKey> toTableKey(final List<AfiSafi> afiSafis, final BGPTableTypeRegistryConsumer
 241             tableTypeRegistry) {
 242         return afiSafis.stream()
 243                 .map(afiSafi -> tableTypeRegistry.getTableKey(afiSafi.getAfiSafiName()))
 244                 .filter(Optional::isPresent)
 245                 .map(Optional::get)
 246                 .collect(Collectors.toSet());
 247     }
 248
 249     static boolean isActive(final Neighbor neighbor, final PeerGroup peerGroup) {
 250         Optional<Boolean> activeConnection = peerGroup == null ? Optional.empty() : isActive(peerGroup.getTransport());
 251         if (!activeConnection.isPresent()) {
 252             activeConnection = isActive(neighbor.getTransport());
 253         }
 254         return activeConnection.orElse(Boolean.TRUE);
 255     }
 256
 257     private static Optional<Boolean> isActive(final Transport transport) {
 258         if (transport != null) {
 259             final Config config = transport.getConfig();
 260             if (config != null) {
 261                 final Boolean passive = config.isPassiveMode();
 262                 if (passive != null) {
 263                     return Optional.of(!passive);
 264                 }
 265             }
 266         }
 267         return Optional.empty();
 268     }
 269
 270     static PeerRole toPeerRole(final BgpNeighborGroup neighbor) {
 271         if (isRrClient(neighbor)) {
 272             return PeerRole.RrClient;
 273         }
 274
 275         if (neighbor.getConfig() != null) {
 276             final PeerType peerType = neighbor.getConfig().getPeerType();
 277             if (peerType == PeerType.EXTERNAL) {
 278                 return PeerRole.Ebgp;
 279             } else if (peerType == PeerType.INTERNAL) {
 280                 return PeerRole.Ibgp;
 281             }
 282         }
 283         return null;
 284     }
 285
 286     static @NonNull PeerRole toPeerRole(final Neighbor neighbor, final PeerGroup peerGroup) {
 287         PeerRole role = null;
 288         if (peerGroup != null) {
 289             role = toPeerRole(peerGroup);
 290         }
 291
 292         if (role == null) {
 293             role = toPeerRole(neighbor);
 294         }
 295
 296         if (role == null) {
 297             return PeerRole.Ibgp;
 298         }
 299         return role;
 300     }
 301
 302     static int getHoldTimer(final Neighbor neighbor, final PeerGroup peerGroup) {
 303         Integer hold = null;
 304         if (peerGroup != null) {
 305             hold = getHoldTimer(peerGroup.getTimers());
 306         }
 307
 308         if (hold == null) {
 309             hold = getHoldTimer(neighbor.getTimers());
 310         }
 311
 312         if (hold == null) {
 313             return HOLDTIMER;
 314         }
 315
 316         return hold;
 317     }
 318
 319     private static @Nullable Integer getHoldTimer(final Timers timers) {
 320         if (timers == null) {
 321             return null;
 322         }
 323         final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.timers
 324                 .Config config = timers.getConfig();
 325         if (config != null && config.getHoldTime() != null) {
 326             return config.getHoldTime().intValue();
 327         }
 328         return null;
 329     }
 330
 331     static int getGracefulRestartTimer(final Neighbor neighbor, final PeerGroup peerGroup, final int holdTimer) {
 332         Uint16 timer = null;
 333         if (peerGroup != null) {
 334             timer = getGracefulRestartTimer(peerGroup.getGracefulRestart());
 335         }
 336
 337         if (timer == null) {
 338             timer = getGracefulRestartTimer(neighbor.getGracefulRestart());
 339         }
 340
 341         /*
 342          * RFC4724: "A suggested default for the Restart Time is a value less than or
 343          * equal to the HOLDTIME carried in the OPEN."
 344          */
 345         return timer == null ? holdTimer : timer.toJava();
 346     }
 347
 348     private static @Nullable Uint16 getGracefulRestartTimer(final GracefulRestart gracefulRestart) {
 349         if (gracefulRestart != null) {
 350             final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.graceful.restart.graceful
 351                     .restart.Config config = gracefulRestart.getConfig();
 352             if (config != null) {
 353                 return config.getRestartTime();
 354             }
 355         }
 356         return null;
 357     }
 358
 359     static @NonNull AsNumber getRemotePeerAs(final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009
 360             .bgp.neighbor.group.Config config, final PeerGroup peerGroup, final AsNumber localAs) {
 361         AsNumber neighborAs = null;
 362         if (peerGroup != null) {
 363             neighborAs = getRemotePeerAs(peerGroup.getConfig());
 364         }
 365
 366         if (neighborAs == null) {
 367             neighborAs = getRemotePeerAs(config);
 368         }
 369
 370         if (neighborAs == null) {
 371             return localAs;
 372         }
 373         return neighborAs;
 374     }
 375
 376     private static AsNumber getRemotePeerAs(final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp
 377             .rev151009.bgp.neighbor.group.@Nullable Config config) {
 378         return config == null ? null : config.getPeerAs();
 379     }
 380
 381     static @NonNull AsNumber getLocalPeerAs(final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp
 382             .rev151009.bgp.neighbor.group.@Nullable Config config, final @NonNull AsNumber globalAs) {
 383         if (config != null) {
 384             final AsNumber peerAs = config.getLocalAs();
 385             if (peerAs != null) {
 386                 return peerAs;
 387             }
 388         }
 389         return globalAs;
 390     }
 391
 392     static int getRetryTimer(final Neighbor neighbor, final PeerGroup peerGroup) {
 393         Integer retryTimer = null;
 394         if (peerGroup != null) {
 395             retryTimer = getRetryTimer(peerGroup.getTimers());
 396         }
 397
 398         if (retryTimer == null) {
 399             retryTimer = getRetryTimer(neighbor.getTimers());
 400         }
 401
 402         if (retryTimer == null) {
 403             return CONNECT_RETRY;
 404         }
 405
 406         return retryTimer;
 407     }
 408
 409     private static @Nullable Integer getRetryTimer(final Timers timers) {
 410         if (timers == null) {
 411             return null;
 412         }
 413         final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.timers
 414                 .Config config = timers.getConfig();
 415         if (config != null && config.getConnectRetry() != null) {
 416             return config.getConnectRetry().intValue();
 417         }
 418         return null;
 419     }
 420
 421     static @NonNull PortNumber getPort(final Neighbor neighbor, final PeerGroup peerGroup) {
 422         PortNumber port = null;
 423         if (peerGroup != null) {
 424             port = getPort(peerGroup.getTransport(), PeerGroupTransportConfig.class);
 425         }
 426
 427         if (port == null) {
 428             port = getPort(neighbor.getTransport(), NeighborTransportConfig.class);
 429         }
 430
 431         if (port == null) {
 432             return PORT;
 433         }
 434
 435         return port;
 436     }
 437
 438     private static <T extends TransportConfig & Augmentation<Config>> @Nullable PortNumber getPort(
 439             final @Nullable Transport transport, final Class<T> augment) {
 440         if (transport != null) {
 441             final Config config = transport.getConfig();
 442             if (config != null) {
 443                 final T peerTc = config.augmentation(augment);
 444                 if (peerTc != null) {
 445                     return peerTc.getRemotePort();
 446                 }
 447             }
 448         }
 449         return null;
 450     }
 451
 452     static @Nullable IpAddress getLocalAddress(@Nullable final Transport transport) {
 453         if (transport != null && transport.getConfig() != null) {
 454             final BgpNeighborTransportConfig.LocalAddress localAddress = transport.getConfig().getLocalAddress();
 455             if (localAddress != null) {
 456                 return localAddress.getIpAddress();
 457             }
 458         }
 459         return null;
 460     }
 461
 462     static @Nullable RevisedErrorHandlingSupport getRevisedErrorHandling(final PeerRole role,final PeerGroup peerGroup,
 463             final Neighbor neighbor) {
 464         Optional<Boolean> enabled = getRevisedErrorHandling(neighbor);
 465         if (!enabled.isPresent()) {
 466             enabled = getRevisedErrorHandling(peerGroup);
 467         }
 468         if (!enabled.orElse(Boolean.FALSE)) {
 469             return null;
 470         }
 471         switch (role) {
 472             case Ebgp:
 473                 return RevisedErrorHandlingSupportImpl.forExternalPeer();
 474             case Ibgp:
 475             case Internal:
 476             case RrClient:
 477                 return RevisedErrorHandlingSupportImpl.forInternalPeer();
 478             default:
 479                 throw new IllegalStateException("Unhandled role " + role);
 480         }
 481     }
 482
 483     private static Optional<Boolean> getRevisedErrorHandling(final BgpNeighborGroup group) {
 484         if (group == null) {
 485             return Optional.empty();
 486         }
 487         final ErrorHandling errorHandling = group.getErrorHandling();
 488         if (errorHandling == null) {
 489             return Optional.empty();
 490         }
 491         final org.opendaylight.yang.gen.v1.http.openconfig.net.yang.bgp.rev151009.bgp.neighbor.group.error.handling
 492             .Config config = errorHandling.getConfig();
 493         return config == null ? Optional.empty() : Optional.of(config.isTreatAsWithdraw());
 494     }
 495 }