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.rib.rev130925.bgp.rib.rib.Peer;
  25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.bgp.rib.rib.peer.AdjRibIn;
  26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.bgp.rib.rib.peer.EffectiveRibIn;
  27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.Tables;
  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(Peer.QNAME).node(AdjRibIn.QNAME).node(Tables.QNAME).node(Tables.QNAME);
  75             final DOMDataTreeIdentifier treeId = new DOMDataTreeIdentifier(LogicalDatastoreType.OPERATIONAL, tableId);
  76             LOG.debug("Registered Effective RIB on {}", tableId);
  77             this.reg = service.registerDataTreeChangeListener(treeId, this);
  78         }
  79
  80         private void processRoute(final DOMDataWriteTransaction tx, final RIBSupport ribSupport, final AbstractImportPolicy policy, final YangInstanceIdentifier routesPath, final DataTreeCandidateNode route) {
  81             LOG.debug("Process route {}", route);
  82             switch (route.getModificationType()) {
  83             case DELETE:
  84                 // Delete has already been affected by the store in caller, so this is a no-op.
  85                 break;
  86             case UNMODIFIED:
  87                 // No-op
  88                 break;
  89             case SUBTREE_MODIFIED:
  90             case WRITE:
  91                 // Lookup per-table attributes from RIBSupport
  92                 final ContainerNode advertisedAttrs = (ContainerNode) NormalizedNodes.findNode(route.getDataAfter(), ribSupport.routeAttributesIdentifier()).orNull();
  93                 final ContainerNode effectiveAttrs;
  94
  95                 if (advertisedAttrs != null) {
  96                     effectiveAttrs = policy.effectiveAttributes(advertisedAttrs);
  97
  98                     /*
  99                      * Speed hack: if we determine that the policy has passed the attributes
 100                      * back unmodified, the corresponding change has already been written in
 101                      * our caller. There is no need to perform any further processing.
 102                      *
 103                      * We also use direct object comparison to make the check very fast, as
 104                      * it may not be that common, in which case it does not make sense to pay
 105                      * the full equals price.
 106                      */
 107                     if (effectiveAttrs == advertisedAttrs) {
 108                         LOG.trace("Effective and local attributes are equal. Quit processing route {}", route);
 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", routeId);
 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                 LOG.debug("Process table children {}", child);
 136                 switch (child.getModificationType()) {
 137                 case DELETE:
 138                     tx.delete(LogicalDatastoreType.OPERATIONAL, tablePath.node(child.getIdentifier()));
 139                     break;
 140                 case UNMODIFIED:
 141                     // No-op
 142                     break;
 143                 case SUBTREE_MODIFIED:
 144                 case WRITE:
 145                     tx.put(LogicalDatastoreType.OPERATIONAL, tablePath.node(child.getIdentifier()), child.getDataAfter().get());
 146
 147                     // Routes are special, as they may end up being filtered. The previous put conveniently
 148                     // ensured that we have them in at target, so a subsequent delete will not fail :)
 149                     if (TABLE_ROUTES.equals(child.getIdentifier())) {
 150                         final YangInstanceIdentifier routesPath = tablePath.node(Routes.QNAME);
 151                         for (final DataTreeCandidateNode route : ribSupport.changedRoutes(child)) {
 152                             processRoute(tx, ribSupport, policy, routesPath, route);
 153                         }
 154                     }
 155                     break;
 156                 default:
 157                     LOG.warn("Ignoring unhandled child {}", child);
 158                     break;
 159                 }
 160             }
 161         }
 162
 163         private RIBSupportContext getRibSupport(final NodeIdentifierWithPredicates tableKey) {
 164             return this.registry.getRIBSupportContext(tableKey);
 165         }
 166
 167         private YangInstanceIdentifier effectiveTablePath(final NodeIdentifierWithPredicates peerKey, final NodeIdentifierWithPredicates tableKey) {
 168             return this.ribId.node(Peer.QNAME).node(peerKey).node(EffectiveRibIn.QNAME).node(Tables.QNAME).node(tableKey);
 169         }
 170
 171         private void modifyTable(final DOMDataWriteTransaction tx, final NodeIdentifierWithPredicates peerKey, final NodeIdentifierWithPredicates tableKey, final DataTreeCandidateNode table) {
 172             final RIBSupportContext ribSupport = getRibSupport(tableKey);
 173             final YangInstanceIdentifier tablePath = effectiveTablePath(peerKey, tableKey);
 174
 175             processTableChildren(tx, ribSupport.getRibSupport(), peerKey, tablePath, table.getChildNodes());
 176         }
 177
 178         private void writeTable(final DOMDataWriteTransaction tx, final NodeIdentifierWithPredicates peerKey, final NodeIdentifierWithPredicates tableKey, final DataTreeCandidateNode table) {
 179             final RIBSupportContext ribSupport = getRibSupport(tableKey);
 180             final YangInstanceIdentifier tablePath = effectiveTablePath(peerKey, tableKey);
 181
 182             // Create an empty table
 183             ribSupport.clearTable(tx,tablePath);
 184
 185             processTableChildren(tx, ribSupport.getRibSupport(), peerKey, tablePath, table.getChildNodes());
 186         }
 187
 188         @Override
 189         public void onDataTreeChanged(final Collection<DataTreeCandidate> changes) {
 190             LOG.trace("Data changed called to effective RIB. Change : {}", changes);
 191             final DOMDataWriteTransaction tx = this.chain.newWriteOnlyTransaction();
 192
 193             for (final DataTreeCandidate tc : changes) {
 194                 final YangInstanceIdentifier rootPath = tc.getRootPath();
 195
 196                 // Obtain the peer's key
 197                 final NodeIdentifierWithPredicates peerKey = IdentifierUtils.peerKey(rootPath);
 198
 199                 // Extract the table key, this should be safe based on the path where we subscribed,
 200                 // but let's verify explicitly.
 201                 final PathArgument lastArg = rootPath.getLastPathArgument();
 202                 Verify.verify(lastArg instanceof NodeIdentifierWithPredicates, "Unexpected type %s in path %s", lastArg.getClass(), rootPath);
 203                 final NodeIdentifierWithPredicates tableKey = (NodeIdentifierWithPredicates) lastArg;
 204
 205                 final DataTreeCandidateNode root = tc.getRootNode();
 206                 switch (root.getModificationType()) {
 207                 case DELETE:
 208                     // delete the corresponding effective table
 209                     tx.delete(LogicalDatastoreType.OPERATIONAL, effectiveTablePath(peerKey, tableKey));
 210                     break;
 211                 case SUBTREE_MODIFIED:
 212                     modifyTable(tx, peerKey, tableKey, root);
 213                     break;
 214                 case UNMODIFIED:
 215                     LOG.info("Ignoring spurious notification on {} data {}", rootPath, root);
 216                     break;
 217                 case WRITE:
 218                     writeTable(tx, peerKey, tableKey, root);
 219                     break;
 220                 default:
 221                     LOG.warn("Ignoring unhandled root {}", root);
 222                     break;
 223                 }
 224             }
 225
 226             tx.submit();
 227         }
 228
 229         @Override
 230         public void close() {
 231             // FIXME: wipe all effective routes?
 232             this.reg.close();
 233         }
 234     }
 235
 236     private final ImportPolicyPeerTracker peerPolicyTracker;
 237     private final AdjInTracker adjInTracker;
 238
 239     static EffectiveRibInWriter create(@Nonnull final DOMDataTreeChangeService service, @Nonnull final DOMTransactionChain chain,
 240         @Nonnull final YangInstanceIdentifier ribId, @Nonnull final PolicyDatabase pd, @Nonnull final RIBSupportContextRegistry registry) {
 241         return new EffectiveRibInWriter(service, chain, ribId, pd, registry);
 242     }
 243
 244     private EffectiveRibInWriter(final DOMDataTreeChangeService service, final DOMTransactionChain chain, final YangInstanceIdentifier ribId,
 245         final PolicyDatabase pd, final RIBSupportContextRegistry registry) {
 246         this.peerPolicyTracker = new ImportPolicyPeerTracker(service, ribId, pd);
 247         this.adjInTracker = new AdjInTracker(service, registry, chain, ribId);
 248     }
 249
 250     @Override
 251     public void close() {
 252         this.adjInTracker.close();
 253         this.peerPolicyTracker.close();
 254     }
 255 }