bgp/l3vpn/src/main/java/org/opendaylight/protocol/bgp/l3vpn/AbstractVpnNlriParser.java

   1 /*
   2  * Copyright (c) 2016 Brocade Communications 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.l3vpn;
   9
  10 import com.google.common.base.Preconditions;
  11 import io.netty.buffer.ByteBuf;
  12 import io.netty.buffer.Unpooled;
  13 import java.util.ArrayList;
  14 import java.util.List;
  15 import org.opendaylight.bgp.concepts.RouteDistinguisherUtil;
  16 import org.opendaylight.protocol.bgp.labeled.unicast.LUNlriParser;
  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.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IpPrefix;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.labeled.unicast.rev171207.labeled.unicast.LabelStack;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev171207.path.attributes.Attributes;
  23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.Attributes1;
  24 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.Attributes2;
  25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.destination.DestinationType;
  26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.MpReachNlriBuilder;
  27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.MpUnreachNlriBuilder;
  28 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.mp.reach.nlri.AdvertizedRoutes;
  29 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev171207.update.attributes.mp.unreach.nlri.WithdrawnRoutes;
  30 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.AddressFamily;
  31 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.vpn.rev171207.l3vpn.ip.destination.type.VpnDestination;
  32 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.vpn.rev171207.l3vpn.ip.destination.type.VpnDestinationBuilder;
  33 import org.opendaylight.yangtools.yang.binding.DataObject;
  34 import org.slf4j.Logger;
  35 import org.slf4j.LoggerFactory;
  36
  37 public abstract class AbstractVpnNlriParser implements NlriParser, NlriSerializer {
  38     private static final Logger LOG = LoggerFactory.getLogger(AbstractVpnNlriParser.class);
  39
  40     protected abstract List<VpnDestination> getWithdrawnVpnDestination(DestinationType dstType);
  41
  42     protected abstract List<VpnDestination> getAdvertizedVpnDestination(DestinationType dstType);
  43
  44     protected abstract WithdrawnRoutes getWithdrawnRoutesByDestination(List<VpnDestination> dst);
  45
  46     protected abstract AdvertizedRoutes getAdvertizedRoutesByDestination(List<VpnDestination> dst);
  47
  48     private static void serializeNlri(final List<VpnDestination> dests, final boolean isWithdrawnRoute, final ByteBuf buffer) {
  49         final ByteBuf nlriByteBuf = Unpooled.buffer();
  50         for (final VpnDestination dest : dests) {
  51             final List<LabelStack> labelStack = dest.getLabelStack();
  52             final IpPrefix prefix = dest.getPrefix();
  53             LOG.debug("Serializing Nlri: VpnDestination={}, IpPrefix={}", dest, prefix);
  54             AbstractVpnNlriParser.serializeLengtField(prefix, labelStack, nlriByteBuf);
  55             LUNlriParser.serializeLabelStackEntries(labelStack, isWithdrawnRoute, nlriByteBuf);
  56             RouteDistinguisherUtil.serializeRouteDistinquisher(dest.getRouteDistinguisher(), nlriByteBuf);
  57             Preconditions.checkArgument(prefix.getIpv6Prefix() != null || prefix.getIpv4Prefix() != null, "Ipv6 or Ipv4 prefix is missing.");
  58             LUNlriParser.serializePrefixField(prefix, nlriByteBuf);
  59         }
  60         buffer.writeBytes(nlriByteBuf);
  61     }
  62
  63     /**
  64      * Serialize the length field Length field contains one Byte which represents the length of label stack and prefix in bits
  65      * @param prefix ipPrefix
  66      * @param labelStack list of labelStack
  67      * @param nlriByteBuf ByteBuf
  68      */
  69     static void serializeLengtField(final IpPrefix prefix, final List<LabelStack> labelStack, final ByteBuf nlriByteBuf) {
  70         final int prefixLenght = LUNlriParser.getPrefixLength(prefix);
  71         int labelStackLenght = 0;
  72         if(labelStack != null) {
  73             labelStackLenght = LUNlriParser.LABEL_LENGTH * labelStack.size();
  74         }
  75         nlriByteBuf.writeByte((labelStackLenght + prefixLenght + RouteDistinguisherUtil.RD_LENGTH) * Byte.SIZE);
  76     }
  77
  78
  79     private static List<VpnDestination> parseNlri(final ByteBuf nlri, final Class<? extends AddressFamily> afi) {
  80         if (!nlri.isReadable()) {
  81             return null;
  82         }
  83         final List<VpnDestination> dests = new ArrayList<>();
  84
  85         while (nlri.isReadable()) {
  86             final VpnDestinationBuilder builder = new VpnDestinationBuilder();
  87             final short length = nlri.readUnsignedByte();
  88             final List<LabelStack> labels = LUNlriParser.parseLabel(nlri);
  89             builder.setLabelStack(labels);
  90             final int labelNum = labels != null ? labels.size() : 1;
  91             final int prefixLen = length - (LUNlriParser.LABEL_LENGTH * Byte.SIZE * labelNum) - (RouteDistinguisherUtil.RD_LENGTH * Byte.SIZE);
  92             builder.setRouteDistinguisher(RouteDistinguisherUtil.parseRouteDistinguisher(nlri));
  93             Preconditions.checkState(prefixLen > 0, "A valid VPN IP prefix is required.");
  94             builder.setPrefix(LUNlriParser.parseIpPrefix(nlri, prefixLen, afi));
  95             dests.add(builder.build());
  96         }
  97         return dests;
  98     }
  99
 100     @Override
 101     public void serializeAttribute(final DataObject attribute, final ByteBuf byteAggregator) {
 102         Preconditions.checkArgument(attribute instanceof Attributes, "Attribute parameter is not a Attributes object");
 103         final Attributes pathAttributes = (Attributes) attribute;
 104         final Attributes1 pathAttributes1 = pathAttributes.getAugmentation(Attributes1.class);
 105         final Attributes2 pathAttributes2 = pathAttributes.getAugmentation(Attributes2.class);
 106         List<VpnDestination> vpnDst = null;
 107         boolean isWithdrawnRoute = false;
 108         if (pathAttributes1 != null) {
 109             final AdvertizedRoutes routes = (pathAttributes1.getMpReachNlri()).getAdvertizedRoutes();
 110             if (routes != null) {
 111                 vpnDst = getAdvertizedVpnDestination(routes.getDestinationType());
 112             }
 113         } else if (pathAttributes2 != null) {
 114             final WithdrawnRoutes routes = pathAttributes2.getMpUnreachNlri().getWithdrawnRoutes();
 115             if (routes != null) {
 116                 vpnDst = getWithdrawnVpnDestination(routes.getDestinationType());
 117                 isWithdrawnRoute = true;
 118             }
 119         }
 120         if (vpnDst != null) {
 121             serializeNlri(vpnDst, isWithdrawnRoute, byteAggregator);
 122         }
 123     }
 124
 125     @Override
 126     public void parseNlri(final ByteBuf nlri, final MpUnreachNlriBuilder builder) throws BGPParsingException {
 127         if (!nlri.isReadable()) {
 128             return;
 129         }
 130         final List<VpnDestination> dst = parseNlri(nlri, builder.getAfi());
 131         builder.setWithdrawnRoutes(getWithdrawnRoutesByDestination(dst));
 132     }
 133
 134     @Override
 135     public void parseNlri(final ByteBuf nlri, final MpReachNlriBuilder builder) throws BGPParsingException {
 136         if (!nlri.isReadable()) {
 137             return;
 138         }
 139         final List<VpnDestination> dst = parseNlri(nlri, builder.getAfi());
 140         builder.setAdvertizedRoutes(getAdvertizedRoutesByDestination(dst));
 141     }
 142 }