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

   1 /*
   2  * Copyright (c) 2015 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 com.google.common.base.Preconditions;
  11 import com.google.common.base.Verify;
  12 import java.util.Collection;
  13 import javax.annotation.Nonnull;
  14 import javax.annotation.concurrent.NotThreadSafe;
  15 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
  16 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener;
  17 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeService;
  18 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeIdentifier;
  19 import org.opendaylight.controller.md.sal.dom.api.DOMDataWriteTransaction;
  20 import org.opendaylight.controller.md.sal.dom.api.DOMTransactionChain;
  21 import org.opendaylight.protocol.bgp.rib.impl.spi.RIBSupportContext;
  22 import org.opendaylight.protocol.bgp.rib.impl.spi.RIBSupportContextRegistry;
  23 import org.opendaylight.protocol.bgp.rib.spi.RIBSupport;
  24 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.open.bgp.parameters.optional.capabilities.c.parameters.graceful.restart._case.graceful.restart.capability.Tables;
  25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.bgp.rib.rib.Peer;
  26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.bgp.rib.rib.peer.AdjRibIn;
  27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.bgp.rib.rib.peer.EffectiveRibIn;
  28 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.tables.Routes;
  29 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  30 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  31 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  32 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  33 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  34 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  35 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodes;
  36 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  37 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateNode;
  38 import org.slf4j.Logger;
  39 import org.slf4j.LoggerFactory;
  40
  41 /**
  42  * Implementation of the BGP import policy. Listens on all Adj-RIB-In, inspects all inbound
  43  * routes in the context of the advertising peer's role and applies the inbound policy.
  44  *
  45  * Inbound policy is applied as follows:
  46  *
  47  * 1) if the peer is an eBGP peer, perform attribute replacement and filtering
  48  * 2) check if a route is admissible based on attributes attached to it, as well as the
  49  *    advertising peer's role
  50  * 3) output admitting routes with edited attributes into /bgp-rib/rib/peer/effective-rib-in/tables/routes
  51  *
  52  * Note that we maintain the peer roles using a DCL, even if we could look up our internal
  53  * structures. This is done so we maintain causality and loose coupling.
  54  */
  55 @NotThreadSafe
  56 final class EffectiveRibInWriter implements AutoCloseable {
  57     private static final Logger LOG = LoggerFactory.getLogger(EffectiveRibInWriter.class);
  58     private static final NodeIdentifier TABLE_ROUTES = new NodeIdentifier(Routes.QNAME);
  59
  60     /**
  61      * Maintains {@link TableRouteListener} instances.
  62      */
  63     private final class AdjInTracker implements AutoCloseable, DOMDataTreeChangeListener {
  64         private final RIBSupportContextRegistry registry;
  65         private final YangInstanceIdentifier ribId;
  66         private final ListenerRegistration<?> reg;
  67         private final DOMTransactionChain chain;
  68
  69         AdjInTracker(final DOMDataTreeChangeService service, final RIBSupportContextRegistry registry, final DOMTransactionChain chain, final YangInstanceIdentifier ribId) {
  70             this.registry = Preconditions.checkNotNull(registry);
  71             this.chain = Preconditions.checkNotNull(chain);
  72             this.ribId = Preconditions.checkNotNull(ribId);
  73
  74             final YangInstanceIdentifier tableId = ribId.node(Peer.QNAME).node(AdjRibIn.QNAME).node(Tables.QNAME);
  75             final DOMDataTreeIdentifier treeId = new DOMDataTreeIdentifier(LogicalDatastoreType.OPERATIONAL, tableId);
  76             this.reg = service.registerDataTreeChangeListener(treeId, this);
  77         }
  78
  79         private void processRoute(final DOMDataWriteTransaction tx, final RIBSupport ribSupport, final AbstractImportPolicy policy, final YangInstanceIdentifier routesPath, final DataTreeCandidateNode route) {
  80             switch (route.getModificationType()) {
  81             case DELETE:
  82                 // Delete has already been affected by the store in caller, so this is a no-op.
  83                 break;
  84             case MERGE:
  85                 LOG.info("Merge on {} reported, this should never have happened, ignoring", route);
  86                 break;
  87             case UNMODIFIED:
  88                 // No-op
  89                 break;
  90             case SUBTREE_MODIFIED:
  91             case WRITE:
  92                 // Lookup per-table attributes from RIBSupport
  93                 final ContainerNode adverisedAttrs = (ContainerNode) NormalizedNodes.findNode(route.getDataAfter(), ribSupport.routeAttributesIdentifier()).orNull();
  94                 final ContainerNode effectiveAttrs;
  95
  96                 if (adverisedAttrs != null) {
  97                     effectiveAttrs = policy.effectiveAttributes(adverisedAttrs);
  98
  99                     /*
 100                      * Speed hack: if we determine that the policy has passed the attributes
 101                      * back unmodified, the corresponding change has already been written in
 102                      * our caller. There is no need to perform any further processing.
 103                      *
 104                      * We also use direct object comparison to make the check very fast, as
 105                      * it may not be that common, in which case it does not make sense to pay
 106                      * the full equals price.
 107                      */
 108                     if (effectiveAttrs == adverisedAttrs) {
 109                         return;
 110                     }
 111                 } else {
 112                     effectiveAttrs = null;
 113                 }
 114
 115                 final YangInstanceIdentifier routeId = ribSupport.routePath(routesPath, route.getIdentifier());
 116                 LOG.debug("Route {} effective attributes {} towards {}", route.getIdentifier(), effectiveAttrs, routeId);
 117
 118                 if (effectiveAttrs != null) {
 119                     tx.put(LogicalDatastoreType.OPERATIONAL, routeId.node(ribSupport.routeAttributesIdentifier()), effectiveAttrs);
 120                 } else {
 121                     LOG.warn("Route {} advertised empty attributes", route.getDataAfter());
 122                     tx.delete(LogicalDatastoreType.OPERATIONAL,  routeId);
 123                 }
 124                 break;
 125             default:
 126                 LOG.warn("Ignoring unhandled route {}", route);
 127                 break;
 128             }
 129         }
 130
 131         private void processTableChildren(final DOMDataWriteTransaction tx, final RIBSupport ribSupport, final NodeIdentifierWithPredicates peerKey, final YangInstanceIdentifier tablePath, final Collection<DataTreeCandidateNode> children) {
 132             final AbstractImportPolicy policy = EffectiveRibInWriter.this.peerPolicyTracker.policyFor(IdentifierUtils.peerId(peerKey));
 133
 134             for (final DataTreeCandidateNode child : children) {
 135                 switch (child.getModificationType()) {
 136                 case DELETE:
 137                     tx.delete(LogicalDatastoreType.OPERATIONAL, tablePath.node(child.getIdentifier()));
 138                     break;
 139                 case MERGE:
 140                     LOG.info("Merge on {} reported, this should never have happened, ignoring", child);
 141                     break;
 142                 case UNMODIFIED:
 143                     // No-op
 144                     break;
 145                 case SUBTREE_MODIFIED:
 146                 case WRITE:
 147                     tx.put(LogicalDatastoreType.OPERATIONAL, tablePath.node(child.getIdentifier()), child.getDataAfter().get());
 148
 149                     // Routes are special, as they may end up being filtered. The previous put conveniently
 150                     // ensured that we have them in at target, so a subsequent delete will not fail :)
 151                     if (TABLE_ROUTES.equals(child.getIdentifier())) {
 152                         final YangInstanceIdentifier routesPath = tablePath.node(Routes.QNAME);
 153                         for (final DataTreeCandidateNode route : ribSupport.changedRoutes(child)) {
 154                             processRoute(tx, ribSupport, policy, routesPath, route);
 155                         }
 156                     }
 157                     break;
 158                 default:
 159                     LOG.warn("Ignoring unhandled child {}", child);
 160                     break;
 161                 }
 162             }
 163         }
 164
 165         private RIBSupportContext getRibSupport(final NodeIdentifierWithPredicates tableKey) {
 166             // FIXME: use codec to translate tableKey
 167             return this.registry.getRIBSupportContext(null);
 168         }
 169
 170         private YangInstanceIdentifier effectiveTablePath(final NodeIdentifierWithPredicates peerKey, final NodeIdentifierWithPredicates tableKey) {
 171             return this.ribId.node(Peer.QNAME).node(peerKey).node(EffectiveRibIn.QNAME).node(tableKey);
 172         }
 173
 174         private void modifyTable(final DOMDataWriteTransaction tx, final NodeIdentifierWithPredicates peerKey, final NodeIdentifierWithPredicates tableKey, final DataTreeCandidateNode table) {
 175             final RIBSupportContext ribSupport = getRibSupport(tableKey);
 176             final YangInstanceIdentifier tablePath = effectiveTablePath(peerKey, tableKey);
 177
 178             processTableChildren(tx, ribSupport.getRibSupport(), peerKey, tablePath, table.getChildNodes());
 179         }
 180
 181         private void writeTable(final DOMDataWriteTransaction tx, final NodeIdentifierWithPredicates peerKey, final NodeIdentifierWithPredicates tableKey, final DataTreeCandidateNode table) {
 182             final RIBSupportContext ribSupport = getRibSupport(tableKey);
 183             final YangInstanceIdentifier tablePath = effectiveTablePath(peerKey, tableKey);
 184
 185             // Create an empty table
 186             ribSupport.clearTable(tx,tablePath);
 187
 188             processTableChildren(tx, ribSupport.getRibSupport(), peerKey, tablePath, table.getChildNodes());
 189         }
 190
 191         @Override
 192         public void onDataTreeChanged(final Collection<DataTreeCandidate> changes) {
 193             final DOMDataWriteTransaction tx = this.chain.newWriteOnlyTransaction();
 194
 195             for (final DataTreeCandidate tc : changes) {
 196                 final YangInstanceIdentifier rootPath = tc.getRootPath();
 197
 198                 // Obtain the peer's key
 199                 final NodeIdentifierWithPredicates peerKey = IdentifierUtils.peerKey(rootPath);
 200
 201                 // Extract the table key, this should be safe based on the path where we subscribed,
 202                 // but let's verify explicitly.
 203                 final PathArgument lastArg = rootPath.getLastPathArgument();
 204                 Verify.verify(lastArg instanceof NodeIdentifierWithPredicates, "Unexpected type %s in path %s", lastArg.getClass(), rootPath);
 205                 final NodeIdentifierWithPredicates tableKey = (NodeIdentifierWithPredicates) lastArg;
 206
 207                 final DataTreeCandidateNode root = tc.getRootNode();
 208                 switch (root.getModificationType()) {
 209                 case DELETE:
 210                     // delete the corresponding effective table
 211                     tx.delete(LogicalDatastoreType.OPERATIONAL, effectiveTablePath(peerKey, tableKey));
 212                     break;
 213                 case MERGE:
 214                     // TODO: upstream API should never give us this, as it leaks how the delta was created.
 215                     LOG.info("Merge on {} reported, this should never have happened, but attempting to cope", rootPath);
 216                     modifyTable(tx, peerKey, tableKey, root);
 217                     break;
 218                 case SUBTREE_MODIFIED:
 219                     modifyTable(tx, peerKey, tableKey, root);
 220                     break;
 221                 case UNMODIFIED:
 222                     LOG.info("Ignoring spurious notification on {} data {}", rootPath, root);
 223                     break;
 224                 case WRITE:
 225                     writeTable(tx, peerKey, tableKey, root);
 226                     break;
 227                 default:
 228                     LOG.warn("Ignoring unhandled root {}", root);
 229                     break;
 230                 }
 231             }
 232
 233             tx.submit();
 234         }
 235
 236         @Override
 237         public void close() {
 238             // FIXME: wipe all effective routes?
 239             this.reg.close();
 240         }
 241     }
 242
 243     private final ImportPolicyPeerTracker peerPolicyTracker;
 244     private final AdjInTracker adjInTracker;
 245
 246     static EffectiveRibInWriter create(@Nonnull final DOMDataTreeChangeService service, @Nonnull final DOMTransactionChain chain,
 247         @Nonnull final YangInstanceIdentifier ribId, @Nonnull final PolicyDatabase pd, @Nonnull final RIBSupportContextRegistry registry) {
 248         return new EffectiveRibInWriter(service, chain, ribId, pd, registry);
 249     }
 250
 251     private EffectiveRibInWriter(final DOMDataTreeChangeService service, final DOMTransactionChain chain, final YangInstanceIdentifier ribId,
 252         final PolicyDatabase pd, final RIBSupportContextRegistry registry) {
 253
 254         this.peerPolicyTracker = new ImportPolicyPeerTracker(service, ribId, pd);
 255         this.adjInTracker = new AdjInTracker(service, registry, chain, ribId);
 256     }
 257
 258     @Override
 259     public void close() {
 260         this.adjInTracker.close();
 261         this.peerPolicyTracker.close();
 262     }
 263 }