bgp/linkstate/src/main/java/org/opendaylight/protocol/bgp/linkstate/nlri/LinkstateNlriParser.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.linkstate.nlri;
   9
  10 import com.google.common.base.Preconditions;
  11 import com.google.common.collect.Lists;
  12 import io.netty.buffer.ByteBuf;
  13 import io.netty.buffer.Unpooled;
  14 import java.math.BigInteger;
  15 import java.util.List;
  16 import org.opendaylight.protocol.bgp.linkstate.TlvUtil;
  17 import org.opendaylight.protocol.bgp.parser.BGPParsingException;
  18 import org.opendaylight.protocol.bgp.parser.spi.NlriParser;
  19 import org.opendaylight.protocol.bgp.parser.spi.NlriSerializer;
  20 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.Identifier;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.NlriType;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.NodeIdentifier;
  23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.ProtocolId;
  24 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.RouteDistinguisher;
  25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.linkstate.destination.CLinkstateDestination;
  26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.linkstate.destination.CLinkstateDestinationBuilder;
  27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.linkstate.destination.c.linkstate.destination.LocalNodeDescriptors;
  28 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.linkstate.destination.c.linkstate.destination.RemoteNodeDescriptors;
  29 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.update.path.attributes.mp.reach.nlri.advertized.routes.destination.type.DestinationLinkstateCaseBuilder;
  30 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.update.path.attributes.mp.reach.nlri.advertized.routes.destination.type.destination.linkstate._case.DestinationLinkstateBuilder;
  31 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.update.path.attributes.mp.unreach.nlri.withdrawn.routes.destination.type.DestinationLinkstateCase;
  32 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.update.PathAttributes;
  33 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.PathAttributes1;
  34 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.PathAttributes2;
  35 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.path.attributes.MpReachNlriBuilder;
  36 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.path.attributes.MpUnreachNlri;
  37 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.path.attributes.MpUnreachNlriBuilder;
  38 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.path.attributes.mp.reach.nlri.AdvertizedRoutes;
  39 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.path.attributes.mp.reach.nlri.AdvertizedRoutesBuilder;
  40 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.path.attributes.mp.unreach.nlri.WithdrawnRoutesBuilder;
  41 import org.opendaylight.yangtools.yang.binding.DataObject;
  42 import org.slf4j.Logger;
  43 import org.slf4j.LoggerFactory;
  44
  45 /**
  46  * Parser and serializer for Linkstate NLRI.
  47  */
  48 public final class LinkstateNlriParser implements NlriParser, NlriSerializer {
  49     private static final Logger LOG = LoggerFactory.getLogger(LinkstateNlriParser.class);
  50     private static final int ROUTE_DISTINGUISHER_LENGTH = 8;
  51     private static final int PROTOCOL_ID_LENGTH = 1;
  52     private static final int IDENTIFIER_LENGTH = 8;
  53
  54     private static final int TYPE_LENGTH = 2;
  55     private static final int LENGTH_SIZE = 2;
  56
  57
  58     private static final int LOCAL_NODE_DESCRIPTORS = 256;
  59     private static final int REMOTE_NODE_DESCRIPTORS = 257;
  60
  61     private final boolean isVpn;
  62
  63     public LinkstateNlriParser(final boolean isVpn) {
  64         this.isVpn = isVpn;
  65     }
  66
  67     private static NodeIdentifier parseLink(final CLinkstateDestinationBuilder builder, final ByteBuf buffer) throws BGPParsingException {
  68         final int type = buffer.readUnsignedShort();
  69         final int length = buffer.readUnsignedShort();
  70         final NodeIdentifier remote = null;
  71         if (type == REMOTE_NODE_DESCRIPTORS) {
  72             builder.setRemoteNodeDescriptors((RemoteNodeDescriptors) NodeNlriParser.parseNodeDescriptors(buffer.slice(buffer.readerIndex(), length), false));
  73             buffer.skipBytes(length);
  74         }
  75         builder.setLinkDescriptors(LinkNlriParser.parseLinkDescriptors(buffer.slice()));
  76         return remote;
  77     }
  78
  79     /**
  80      * Parses common parts for Link State Nodes, Links and Prefixes, that includes protocol ID and identifier tlv.
  81      *
  82      * @param nlri as byte array
  83      * @return {@link CLinkstateDestination}
  84      * @throws BGPParsingException if parsing was unsuccessful
  85      */
  86     public static List<CLinkstateDestination> parseNlri(final ByteBuf nlri, final boolean isVpn) throws BGPParsingException {
  87         if (!nlri.isReadable()) {
  88             return null;
  89         }
  90         final List<CLinkstateDestination> dests = Lists.newArrayList();
  91
  92         CLinkstateDestinationBuilder builder = null;
  93
  94         while (nlri.isReadable()) {
  95             builder = new CLinkstateDestinationBuilder();
  96             final NlriType type = NlriType.forValue(nlri.readUnsignedShort());
  97             builder.setNlriType(type);
  98
  99             // length means total length of the tlvs including route distinguisher not including the type field
 100             final int length = nlri.readUnsignedShort();
 101             RouteDistinguisher distinguisher = null;
 102             if (isVpn) {
 103                 // this parses route distinguisher
 104                 distinguisher = new RouteDistinguisher(BigInteger.valueOf(nlri.readLong()));
 105                 builder.setDistinguisher(distinguisher);
 106             }
 107             // parse source protocol
 108             final ProtocolId sp = ProtocolId.forValue(nlri.readByte());
 109             builder.setProtocolId(sp);
 110
 111             // parse identifier
 112             final Identifier identifier = new Identifier(BigInteger.valueOf(nlri.readLong()));
 113             builder.setIdentifier(identifier);
 114
 115             // if we are dealing with linkstate nodes/links, parse local node descriptor
 116             NodeIdentifier localDescriptor = null;
 117             int locallength = 0;
 118             final int localtype = nlri.readUnsignedShort();
 119             locallength = nlri.readUnsignedShort();
 120             if (localtype == LOCAL_NODE_DESCRIPTORS) {
 121                 localDescriptor = NodeNlriParser.parseNodeDescriptors(nlri.slice(nlri.readerIndex(), locallength), true);
 122             }
 123             nlri.skipBytes(locallength);
 124             builder.setLocalNodeDescriptors((LocalNodeDescriptors) localDescriptor);
 125             final int restLength = length - (isVpn ? ROUTE_DISTINGUISHER_LENGTH : 0) - PROTOCOL_ID_LENGTH - IDENTIFIER_LENGTH
 126                 - TYPE_LENGTH - LENGTH_SIZE - locallength;
 127             LOG.trace("Restlength {}", restLength);
 128             final ByteBuf rest = nlri.slice(nlri.readerIndex(), restLength);
 129             switch (type) {
 130             case Link:
 131                 parseLink(builder, rest);
 132                 break;
 133             case Ipv4Prefix:
 134                 builder.setPrefixDescriptors(PrefixNlriParser.parsePrefixDescriptors(rest, true));
 135                 break;
 136             case Ipv6Prefix:
 137                 builder.setPrefixDescriptors(PrefixNlriParser.parsePrefixDescriptors(rest, false));
 138                 break;
 139             case Node:
 140                 // node nlri is already parsed as it contains only the common fields for node and link nlri
 141                 break;
 142             default:
 143                 break;
 144             }
 145             nlri.skipBytes(restLength);
 146             dests.add(builder.build());
 147         }
 148         return dests;
 149     }
 150
 151     @Override
 152     public void parseNlri(final ByteBuf nlri, final MpUnreachNlriBuilder builder) throws BGPParsingException {
 153         if (!nlri.isReadable()) {
 154             return;
 155         }
 156         final List<CLinkstateDestination> dst = parseNlri(nlri, this.isVpn);
 157
 158         builder.setWithdrawnRoutes(new WithdrawnRoutesBuilder().setDestinationType(
 159             new org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.update.path.attributes.mp.unreach.nlri.withdrawn.routes.destination.type.DestinationLinkstateCaseBuilder().setDestinationLinkstate(
 160                 new org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.update.path.attributes.mp.unreach.nlri.withdrawn.routes.destination.type.destination.linkstate._case.DestinationLinkstateBuilder().setCLinkstateDestination(
 161                     dst).build()).build()).build());
 162     }
 163
 164     @Override
 165     public void parseNlri(final ByteBuf nlri, final MpReachNlriBuilder builder) throws BGPParsingException {
 166         if (!nlri.isReadable()) {
 167             return;
 168         }
 169         final List<CLinkstateDestination> dst = parseNlri(nlri, this.isVpn);
 170
 171         builder.setAdvertizedRoutes(new AdvertizedRoutesBuilder().setDestinationType(
 172             new DestinationLinkstateCaseBuilder().setDestinationLinkstate(
 173                 new DestinationLinkstateBuilder().setCLinkstateDestination(dst).build()).build()).build());
 174     }
 175
 176     /**
 177      * Serializes Linkstate NLRI to byte array. We need this as NLRI serves as a key in upper layers.
 178      *
 179      * @param destination Linkstate NLRI to be serialized
 180      */
 181     public static void serializeNlri(final CLinkstateDestination destination, final ByteBuf buffer) {
 182         final ByteBuf nlriByteBuf = Unpooled.buffer();
 183         if (destination.getDistinguisher() != null) {
 184             nlriByteBuf.writeBytes(destination.getDistinguisher().getValue().toByteArray());
 185         }
 186         nlriByteBuf.writeByte(destination.getProtocolId().getIntValue());
 187         nlriByteBuf.writeLong(destination.getIdentifier().getValue().longValue());
 188
 189         // serialize local node descriptors
 190         final ByteBuf ldescs = Unpooled.buffer();
 191         NodeNlriParser.serializeNodeDescriptors(destination.getLocalNodeDescriptors(), ldescs);
 192         TlvUtil.writeTLV(LOCAL_NODE_DESCRIPTORS, ldescs, nlriByteBuf);
 193
 194         switch (destination.getNlriType()) {
 195         case Ipv4Prefix:
 196         case Ipv6Prefix:
 197             if (destination.getPrefixDescriptors() != null) {
 198                 PrefixNlriParser.serializePrefixDescriptors(destination.getPrefixDescriptors(), nlriByteBuf);
 199             }
 200             break;
 201         case Link:
 202             final ByteBuf rdescs = Unpooled.buffer();
 203             NodeNlriParser.serializeNodeDescriptors(destination.getRemoteNodeDescriptors(), rdescs);
 204             TlvUtil.writeTLV(REMOTE_NODE_DESCRIPTORS, rdescs, nlriByteBuf);
 205             if (destination.getLinkDescriptors() != null) {
 206                 LinkNlriParser.serializeLinkDescriptors(destination.getLinkDescriptors(), nlriByteBuf);
 207             }
 208             break;
 209         case Node:
 210             break;
 211         default:
 212             LOG.warn("Unknown NLRI Type.");
 213             break;
 214         }
 215         TlvUtil.writeTLV(destination.getNlriType().getIntValue(), nlriByteBuf, buffer);
 216     }
 217
 218     @Override
 219     public void serializeAttribute(final DataObject attribute, final ByteBuf byteAggregator) {
 220         Preconditions.checkArgument(attribute instanceof PathAttributes, "Attribute parameter is not a PathAttribute object.");
 221         final PathAttributes pathAttributes = (PathAttributes) attribute;
 222         final PathAttributes1 pathAttributes1 = pathAttributes.getAugmentation(PathAttributes1.class);
 223         final PathAttributes2 pathAttributes2 = pathAttributes.getAugmentation(PathAttributes2.class);
 224         if (pathAttributes1 != null) {
 225             final AdvertizedRoutes routes = (pathAttributes1.getMpReachNlri()).getAdvertizedRoutes();
 226             if (routes != null &&
 227                 routes.getDestinationType()
 228                 instanceof
 229                 org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.update.path.attributes.mp.reach.nlri.advertized.routes.destination.type.DestinationLinkstateCase) {
 230                 final org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.update.path.attributes.mp.reach.nlri.advertized.routes.destination.type.DestinationLinkstateCase
 231                 linkstateCase = (org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.update.path.attributes.mp.reach.nlri.advertized.routes.destination.type.DestinationLinkstateCase) routes.getDestinationType();
 232
 233                 for (final CLinkstateDestination cLinkstateDestination : linkstateCase.getDestinationLinkstate().getCLinkstateDestination()) {
 234                     serializeNlri(cLinkstateDestination, byteAggregator);
 235                 }
 236             }
 237         } else if (pathAttributes2 != null) {
 238             final MpUnreachNlri mpUnreachNlri = pathAttributes2.getMpUnreachNlri();
 239             if (mpUnreachNlri.getWithdrawnRoutes() != null && mpUnreachNlri.getWithdrawnRoutes().getDestinationType() instanceof DestinationLinkstateCase) {
 240                 final DestinationLinkstateCase linkstateCase = (DestinationLinkstateCase) mpUnreachNlri.getWithdrawnRoutes().getDestinationType();
 241                 for (final CLinkstateDestination cLinkstateDestination : linkstateCase.getDestinationLinkstate().getCLinkstateDestination()) {
 242                     serializeNlri(cLinkstateDestination, byteAggregator);
 243                 }
 244             }
 245         }
 246     }
 247 }