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