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

   1 /*
   2  * Copyright (c) 2013 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 java.util.Map;
  11 import java.util.Map.Entry;
  12 import java.util.Set;
  13
  14 import org.opendaylight.protocol.bgp.parser.BGPSession;
  15 import org.opendaylight.protocol.bgp.parser.BGPSessionListener;
  16 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Update;
  17 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.UpdateBuilder;
  18 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.update.PathAttributesBuilder;
  19 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.PathAttributes1;
  20 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.PathAttributes1Builder;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.PathAttributes2;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.path.attributes.MpReachNlriBuilder;
  23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.TablesKey;
  24 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.Ipv4AddressFamily;
  25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.UnicastSubsequentAddressFamily;
  26 import org.slf4j.Logger;
  27 import org.slf4j.LoggerFactory;
  28
  29 import com.google.common.base.Preconditions;
  30 import com.google.common.collect.Maps;
  31
  32 /**
  33  * BGP speaker (without Graceful restart capability) sends KeepAlive message after sending all initial Update messages
  34  * with certain AFI/SAFI. For each AFI/SAFI, it sends one KA message. As it is undetermined which KA message belongs to
  35  * which AFI/SAFI, an algorithm needed to be implemented.
  36  */
  37 public class BGPSynchronization {
  38
  39         private static final Logger LOG = LoggerFactory.getLogger(BGPSynchronization.class);
  40
  41         private static class SyncVariables {
  42
  43                 private boolean upd = false;
  44                 private boolean eor = false;
  45
  46                 public void setUpd(final boolean upd) {
  47                         this.upd = upd;
  48                 }
  49
  50                 public void setEorTrue() {
  51                         this.eor = true;
  52                 }
  53
  54                 public boolean getEor() {
  55                         return this.eor;
  56                 }
  57
  58                 public boolean getUpd() {
  59                         return this.upd;
  60                 }
  61         }
  62
  63         private final Map<TablesKey, SyncVariables> syncStorage = Maps.newHashMap();
  64
  65         private final BGPSessionListener listener;
  66
  67         private final BGPSession session;
  68
  69         public BGPSynchronization(final BGPSession bgpSession, final BGPSessionListener listener, final Set<TablesKey> types) {
  70                 this.listener = Preconditions.checkNotNull(listener);
  71                 this.session = Preconditions.checkNotNull(bgpSession);
  72
  73                 for (final TablesKey type : types) {
  74                         this.syncStorage.put(type, new SyncVariables());
  75                 }
  76         }
  77
  78         /**
  79          * For each received Update message, the upd sync variable needs to be updated to true, for particular AFI/SAFI
  80          * combination. Currently we only assume Unicast SAFI. From the Update message we have to extract the AFI. Each
  81          * Update message can contain BGP Object with one type of AFI. If the object is BGP Link, BGP Node or BGPPrefix<?>
  82          * the AFI is Linkstate. In case of BGPRoute, the AFI depends on the IP Address of the prefix.
  83          *
  84          * @param msg received Update message
  85          */
  86         public void updReceived(final Update msg) {
  87                 TablesKey type = null;
  88                 if (msg.getNlri() != null || msg.getWithdrawnRoutes() != null) {
  89                         type = new TablesKey(Ipv4AddressFamily.class, UnicastSubsequentAddressFamily.class);
  90                 } else if (msg.getPathAttributes().getAugmentation(PathAttributes1.class) != null) {
  91                         final PathAttributes1 pa = msg.getPathAttributes().getAugmentation(PathAttributes1.class);
  92                         if (pa.getMpReachNlri() != null) {
  93                                 type = new TablesKey(pa.getMpReachNlri().getAfi(), pa.getMpReachNlri().getSafi());
  94                         }
  95                 } else if (msg.getPathAttributes().getAugmentation(PathAttributes2.class) != null) {
  96                         final PathAttributes2 pa = msg.getPathAttributes().getAugmentation(PathAttributes2.class);
  97                         if (pa.getMpUnreachNlri() != null) {
  98                                 type = new TablesKey(pa.getMpUnreachNlri().getAfi(), pa.getMpUnreachNlri().getSafi());
  99                         }
 100                 }
 101                 final SyncVariables s = this.syncStorage.get(type);
 102                 if (s == null) {
 103                         LOG.warn("BGPTableType was not present in open message : {}", type);
 104                         return;
 105                 }
 106                 s.setUpd(true);
 107         }
 108
 109         /**
 110          * This method is called, when the second KA message is received. It checks each AFI/SAFI sync variables. If they
 111          * are all false, which means, that there was at least one update message followed by one KA, the EOR is sent to
 112          * session.
 113          */
 114         public void kaReceived() {
 115                 for (final Entry<TablesKey, SyncVariables> entry : this.syncStorage.entrySet()) {
 116                         final SyncVariables s = entry.getValue();
 117                         if (!s.getEor()) {
 118                                 if (!s.getUpd()) {
 119                                         s.setEorTrue();
 120                                         LOG.info("BGP Synchronization finished for table {} ", entry.getKey());
 121                                         final Update up = generateEOR(entry.getKey());
 122                                         LOG.debug("Sending synchronization message: {}", up);
 123                                         this.listener.onMessage(this.session, up);
 124                                 }
 125                                 s.setUpd(false);
 126                         }
 127                 }
 128         }
 129
 130         private Update generateEOR(final TablesKey type) {
 131                 if (type.getAfi().equals(Ipv4AddressFamily.class) && type.getSafi().equals(UnicastSubsequentAddressFamily.class)) {
 132                         return new UpdateBuilder().build();
 133                 }
 134                 return new UpdateBuilder().setPathAttributes(
 135                                 new PathAttributesBuilder().addAugmentation(
 136                                                 PathAttributes1.class,
 137                                                 new PathAttributes1Builder().setMpReachNlri(
 138                                                                 new MpReachNlriBuilder().setAfi(type.getAfi()).setSafi(type.getSafi()).build()).build()).build()).build();
 139         }
 140 }