bgp/parser-spi/src/main/java/org/opendaylight/protocol/bgp/parser/spi/pojo/SimpleNlriRegistry.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.parser.spi.pojo;
   9
  10 import java.util.concurrent.ConcurrentHashMap;
  11 import java.util.concurrent.ConcurrentMap;
  12
  13 import org.opendaylight.protocol.bgp.parser.BGPParsingException;
  14 import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl;
  15 import org.opendaylight.protocol.bgp.parser.spi.AddressFamilyRegistry;
  16 import org.opendaylight.protocol.bgp.parser.spi.NlriParser;
  17 import org.opendaylight.protocol.bgp.parser.spi.NlriRegistry;
  18 import org.opendaylight.protocol.bgp.parser.spi.SubsequentAddressFamilyRegistry;
  19 import org.opendaylight.protocol.concepts.AbstractRegistration;
  20 import org.opendaylight.protocol.util.ByteArray;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130918.BgpTableType;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130918.update.path.attributes.MpReachNlri;
  23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130918.update.path.attributes.MpReachNlriBuilder;
  24 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130918.update.path.attributes.MpUnreachNlri;
  25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130918.update.path.attributes.MpUnreachNlriBuilder;
  26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.AddressFamily;
  27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.SubsequentAddressFamily;
  28
  29 import com.google.common.base.Preconditions;
  30 import com.google.common.primitives.UnsignedBytes;
  31
  32 final class SimpleNlriRegistry implements NlriRegistry {
  33         private final ConcurrentMap<BgpTableType, NlriParser> handlers = new ConcurrentHashMap<>();
  34         private final SubsequentAddressFamilyRegistry safiReg;
  35         private final AddressFamilyRegistry afiReg;
  36
  37         public SimpleNlriRegistry(final AddressFamilyRegistry afiReg, final SubsequentAddressFamilyRegistry safiReg) {
  38                 this.afiReg = Preconditions.checkNotNull(afiReg);
  39                 this.safiReg = Preconditions.checkNotNull(safiReg);
  40         }
  41
  42         private static BgpTableType createKey(final Class<? extends AddressFamily> afi,
  43                         final Class<? extends SubsequentAddressFamily> safi) {
  44                 Preconditions.checkNotNull(afi);
  45                 Preconditions.checkNotNull(safi);
  46                 return new BgpTableTypeImpl(afi, safi);
  47         }
  48
  49         synchronized AutoCloseable registerNlriParser(final Class<? extends AddressFamily> afi,
  50                         final Class<? extends SubsequentAddressFamily> safi, final NlriParser parser) {
  51                 final BgpTableType key = createKey(afi, safi);
  52                 final NlriParser prev = handlers.get(key);
  53                 Preconditions.checkState(prev == null, "AFI/SAFI is already bound to parser " + prev);
  54
  55                 handlers.put(key, parser);
  56                 final Object lock = this;
  57                 return new AbstractRegistration() {
  58                         @Override
  59                         protected void removeRegistration() {
  60                                 synchronized (lock) {
  61                                         handlers.remove(key);
  62                                 }
  63                         }
  64                 };
  65         }
  66
  67         private Class<? extends AddressFamily> getAfi(final byte[] header) throws BGPParsingException {
  68                 final int afiVal = UnsignedBytes.toInt(header[0]) * 256 + UnsignedBytes.toInt(header[1]);
  69                 final Class<? extends AddressFamily> afi = afiReg.classForFamily(afiVal);
  70                 if (afi == null) {
  71                         throw new BGPParsingException("Address Family Identifier: '" + afiVal + "' not supported.");
  72                 }
  73
  74                 return afi;
  75         }
  76
  77         private Class<? extends SubsequentAddressFamily> getSafi(final byte[] header) throws BGPParsingException {
  78                 final int safiVal = UnsignedBytes.toInt(header[2]);
  79                 final Class<? extends SubsequentAddressFamily> safi = safiReg.classForFamily(safiVal);
  80                 if (safi == null) {
  81                         throw new BGPParsingException("Subsequent Address Family Identifier: '" + safiVal + "' not supported.");
  82                 }
  83
  84                 return safi;
  85         }
  86
  87         @Override
  88         public MpUnreachNlri parseMpUnreach(final byte[] bytes) throws BGPParsingException {
  89                 final MpUnreachNlriBuilder builder = new MpUnreachNlriBuilder();
  90                 builder.setAfi(getAfi(bytes));
  91                 builder.setSafi(getSafi(bytes));
  92
  93                 final NlriParser parser = handlers.get(createKey(builder.getAfi(), builder.getSafi()));
  94                 parser.parseNlri(ByteArray.subByte(bytes, 3, bytes.length - 3), builder);
  95
  96                 return builder.build();
  97         }
  98
  99         @Override
 100         public MpReachNlri parseMpReach(final byte[] bytes) throws BGPParsingException {
 101                 final MpReachNlriBuilder builder = new MpReachNlriBuilder();
 102                 builder.setAfi(getAfi(bytes));
 103                 builder.setSafi(getSafi(bytes));
 104
 105                 final NlriParser parser = handlers.get(createKey(builder.getAfi(), builder.getSafi()));
 106
 107                 final int nextHopLength = UnsignedBytes.toInt(bytes[3]);
 108                 int byteOffset = 4;
 109
 110                 final byte[] nextHop = ByteArray.subByte(bytes, byteOffset, nextHopLength);
 111                 byteOffset += nextHopLength + 1;
 112
 113                 final byte[] nlri = ByteArray.subByte(bytes, byteOffset, bytes.length - byteOffset);
 114                 parser.parseNlri(nlri, nextHop, builder);
 115
 116                 return builder.build();
 117         }
 118 }