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

   1 /*
   2  * Copyright (c) 2014 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
   9 package org.opendaylight.protocol.bgp.rib.impl;
  10
  11 import com.google.common.base.Objects;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.collect.Maps;
  14 import java.net.Inet4Address;
  15 import java.net.Inet6Address;
  16 import java.net.InetAddress;
  17 import java.net.InetSocketAddress;
  18 import java.net.SocketAddress;
  19 import java.util.Map;
  20 import javax.annotation.concurrent.GuardedBy;
  21 import javax.annotation.concurrent.ThreadSafe;
  22 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  23 import org.opendaylight.protocol.bgp.parser.BGPError;
  24 import org.opendaylight.protocol.bgp.parser.BGPSessionListener;
  25 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
  26 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  27 import org.opendaylight.protocol.bgp.rib.impl.spi.ReusableBGPPeer;
  28 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.IpAddress;
  29 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
  30 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv6Address;
  31 import org.slf4j.Logger;
  32 import org.slf4j.LoggerFactory;
  33
  34 /**
  35  * BGP peer registry that allows only 1 session per BGP peer.
  36  * If second session with peer is established, one of the sessions will be dropped.
  37  * The session with lower source BGP id will be dropped.
  38  */
  39 @ThreadSafe
  40 public final class StrictBGPPeerRegistry implements BGPPeerRegistry {
  41
  42     private static final Logger LOG = LoggerFactory.getLogger(StrictBGPPeerRegistry.class);
  43
  44     // TODO remove backwards compatibility
  45     public static final StrictBGPPeerRegistry GLOBAL = new StrictBGPPeerRegistry();
  46
  47     @GuardedBy("this")
  48     private final Map<IpAddress, ReusableBGPPeer> peers = Maps.newHashMap();
  49     @GuardedBy("this")
  50     private final Map<IpAddress, BGPSessionId> sessionIds = Maps.newHashMap();
  51     @GuardedBy("this")
  52     private final Map<IpAddress, BGPSessionPreferences> peerPreferences = Maps.newHashMap();
  53
  54     @Override
  55     public synchronized void addPeer(final IpAddress ip, final ReusableBGPPeer peer, final BGPSessionPreferences preferences) {
  56         Preconditions.checkNotNull(ip);
  57         Preconditions.checkArgument(!peers.containsKey(ip), "Peer for %s already present", ip);
  58         peers.put(ip, Preconditions.checkNotNull(peer));
  59         peerPreferences.put(ip, Preconditions.checkNotNull(preferences));
  60     }
  61
  62     @Override
  63     public synchronized void removePeer(final IpAddress ip) {
  64         Preconditions.checkNotNull(ip);
  65         peers.remove(ip);
  66     }
  67
  68     @Override
  69     public boolean isPeerConfigured(final IpAddress ip) {
  70         Preconditions.checkNotNull(ip);
  71         return peers.containsKey(ip);
  72     }
  73
  74     private void checkPeerConfigured(final IpAddress ip) {
  75         Preconditions.checkState(isPeerConfigured(ip), "BGP peer with ip: %s not configured, configured peers are: %s", ip, peers.keySet());
  76     }
  77
  78     @Override
  79     public synchronized BGPSessionListener getPeer(final IpAddress ip,
  80             final Ipv4Address sourceId, final Ipv4Address remoteId)
  81             throws BGPDocumentedException {
  82         Preconditions.checkNotNull(ip);
  83         Preconditions.checkNotNull(sourceId);
  84         Preconditions.checkNotNull(remoteId);
  85
  86         checkPeerConfigured(ip);
  87
  88         final BGPSessionId currentConnection = new BGPSessionId(sourceId, remoteId);
  89
  90         if (sessionIds.containsKey(ip)) {
  91             LOG.warn("Duplicate BGP session established with {}", ip);
  92
  93             final BGPSessionId previousConnection = sessionIds.get(ip);
  94
  95             // Session reestablished with different ids
  96             if (!previousConnection.equals(currentConnection)) {
  97                 LOG.warn("BGP session with {} {} has to be dropped. Same session already present {}", ip, currentConnection, previousConnection);
  98                 throw new BGPDocumentedException(
  99                         String.format("BGP session with %s %s has to be dropped. Same session already present %s",
 100                                 ip, currentConnection, previousConnection),
 101                         BGPError.CEASE);
 102
 103             // Session reestablished with lower source bgp id, dropping current
 104             } else if (previousConnection.isHigherDirection(currentConnection)) {
 105                 LOG.warn("BGP session with {} {} has to be dropped. Opposite session already present", ip, currentConnection);
 106                 throw new BGPDocumentedException(
 107                         String.format("BGP session with %s initiated %s has to be dropped. Opposite session already present",
 108                                 ip, currentConnection),
 109                         BGPError.CEASE);
 110
 111             // Session reestablished with higher source bgp id, dropping previous
 112             } else if (currentConnection.isHigherDirection(previousConnection)) {
 113                 LOG.warn("BGP session with {} {} released. Replaced by opposite session", ip, previousConnection);
 114                 peers.get(ip).releaseConnection();
 115                 return peers.get(ip);
 116
 117             // Session reestablished with same source bgp id, dropping current as duplicate
 118             } else {
 119                 LOG.warn("BGP session with %s initiated from %s to %s has to be dropped. Same session already present", ip, sourceId, remoteId);
 120                 throw new BGPDocumentedException(
 121                         String.format("BGP session with %s initiated %s has to be dropped. Same session already present",
 122                                 ip, currentConnection),
 123                         BGPError.CEASE);
 124             }
 125         }
 126
 127         // Map session id to peer IP address
 128         sessionIds.put(ip, currentConnection);
 129         return peers.get(ip);
 130     }
 131
 132     @Override
 133     public BGPSessionPreferences getPeerPreferences(final IpAddress ip) {
 134         Preconditions.checkNotNull(ip);
 135         checkPeerConfigured(ip);
 136         return peerPreferences.get(ip);
 137     }
 138
 139     /**
 140      * Create IpAddress from SocketAddress. Only InetSocketAddress is accepted with inner address: Inet4Address and Inet6Address.
 141      *
 142      * @throws IllegalArgumentException if submitted socket address is not InetSocketAddress[ipv4 | ipv6]
 143      * @param socketAddress socket address to transform
 144      */
 145     public static IpAddress getIpAddress(final SocketAddress socketAddress) {
 146         Preconditions.checkNotNull(socketAddress);
 147         Preconditions.checkArgument(socketAddress instanceof InetSocketAddress, "Expecting InetSocketAddress but was %s", socketAddress.getClass());
 148         final InetAddress inetAddress = ((InetSocketAddress) socketAddress).getAddress();
 149
 150         if(inetAddress instanceof Inet4Address) {
 151             return new IpAddress(new Ipv4Address(inetAddress.getHostAddress()));
 152         } else if(inetAddress instanceof Inet6Address) {
 153             return new IpAddress(new Ipv6Address(inetAddress.getHostAddress()));
 154         }
 155
 156         throw new IllegalArgumentException("Expecting " + Inet4Address.class + " or " + Inet6Address.class + " but was " + inetAddress.getClass());
 157     }
 158
 159     @Override
 160     public synchronized void close() {
 161         peers.clear();
 162         sessionIds.clear();
 163     }
 164
 165     @Override
 166     public String toString() {
 167         return Objects.toStringHelper(this)
 168                 .add("peers", peers.keySet())
 169                 .toString();
 170     }
 171
 172     /**
 173      * Session identifier that contains (source Bgp Id) -> (destination Bgp Id)
 174      */
 175     private static final class BGPSessionId {
 176         private final Ipv4Address from, to;
 177
 178         BGPSessionId(final Ipv4Address from, final Ipv4Address to) {
 179             this.from = Preconditions.checkNotNull(from);
 180             this.to = Preconditions.checkNotNull(to);
 181         }
 182
 183         /**
 184          * Equals does not take direction of connection into account id1 -> id2 and id2 -> id1 are equal
 185          */
 186         @Override
 187         public boolean equals(final Object o) {
 188             if (this == o) {
 189                 return true;
 190             }
 191             if (o == null || getClass() != o.getClass()) {
 192                 return false;
 193             }
 194
 195             final BGPSessionId bGPSessionId = (BGPSessionId) o;
 196
 197             if (!from.equals(bGPSessionId.from) && !from.equals(bGPSessionId.to)) {
 198                 return false;
 199             }
 200             if (!to.equals(bGPSessionId.to) && !to.equals(bGPSessionId.from)) {
 201                 return false;
 202             }
 203
 204             return true;
 205         }
 206
 207         @Override
 208         public int hashCode() {
 209             final int prime = 31;
 210             int result = from.hashCode() + to.hashCode();
 211             result = prime * result;
 212             return result;
 213         }
 214
 215         /**
 216          * Check if this connection is equal to other and if it contains higher source bgp id
 217          */
 218         boolean isHigherDirection(final BGPSessionId other) {
 219             Preconditions.checkState(!this.isSameDirection(other), "Equal sessions with same direction");
 220             return toLong(from) > toLong(other.from);
 221         }
 222
 223         private long toLong(final Ipv4Address from) {
 224             return Long.valueOf(from.getValue().replaceAll("[^0-9]", ""));
 225         }
 226
 227         /**
 228          * Check if 2 connections are equal and face same direction
 229          */
 230         boolean isSameDirection(final BGPSessionId other) {
 231             Preconditions.checkState(this.equals(other), "Only equal sessions can be compared");
 232             return from.equals(other.from);
 233         }
 234
 235         @Override
 236         public String toString() {
 237             return Objects.toStringHelper(this)
 238                     .add("from", from)
 239                     .add("to", to)
 240                     .toString();
 241         }
 242     }
 243 }