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.CharMatcher;
  12 import com.google.common.base.Objects;
  13 import com.google.common.base.Preconditions;
  14 import com.google.common.collect.Maps;
  15 import java.net.Inet4Address;
  16 import java.net.Inet6Address;
  17 import java.net.InetAddress;
  18 import java.net.InetSocketAddress;
  19 import java.net.SocketAddress;
  20 import java.util.Map;
  21 import javax.annotation.concurrent.GuardedBy;
  22 import javax.annotation.concurrent.ThreadSafe;
  23 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  24 import org.opendaylight.protocol.bgp.parser.BGPError;
  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.protocol.bgp.rib.spi.BGPSessionListener;
  29 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.IpAddress;
  30 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
  31 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv6Address;
  32 import org.slf4j.Logger;
  33 import org.slf4j.LoggerFactory;
  34
  35 /**
  36  * BGP peer registry that allows only 1 session per BGP peer.
  37  * If second session with peer is established, one of the sessions will be dropped.
  38  * The session with lower source BGP id will be dropped.
  39  */
  40 @ThreadSafe
  41 public final class StrictBGPPeerRegistry implements BGPPeerRegistry {
  42
  43     private static final Logger LOG = LoggerFactory.getLogger(StrictBGPPeerRegistry.class);
  44
  45     private static final CharMatcher NONDIGIT = CharMatcher.inRange('0', '9').negate();
  46
  47     // TODO remove backwards compatibility
  48     public static final StrictBGPPeerRegistry GLOBAL = new StrictBGPPeerRegistry();
  49
  50     @GuardedBy("this")
  51     private final Map<IpAddress, ReusableBGPPeer> peers = Maps.newHashMap();
  52     @GuardedBy("this")
  53     private final Map<IpAddress, BGPSessionId> sessionIds = Maps.newHashMap();
  54     @GuardedBy("this")
  55     private final Map<IpAddress, BGPSessionPreferences> peerPreferences = Maps.newHashMap();
  56
  57     @Override
  58     public synchronized void addPeer(final IpAddress ip, final ReusableBGPPeer peer, final BGPSessionPreferences preferences) {
  59         Preconditions.checkNotNull(ip);
  60         Preconditions.checkArgument(!this.peers.containsKey(ip), "Peer for %s already present", ip);
  61         this.peers.put(ip, Preconditions.checkNotNull(peer));
  62         this.peerPreferences.put(ip, Preconditions.checkNotNull(preferences));
  63     }
  64
  65     @Override
  66     public synchronized void removePeer(final IpAddress ip) {
  67         Preconditions.checkNotNull(ip);
  68         this.peers.remove(ip);
  69     }
  70
  71     @Override
  72     public boolean isPeerConfigured(final IpAddress ip) {
  73         Preconditions.checkNotNull(ip);
  74         return this.peers.containsKey(ip);
  75     }
  76
  77     private void checkPeerConfigured(final IpAddress ip) {
  78         Preconditions.checkState(isPeerConfigured(ip), "BGP peer with ip: %s not configured, configured peers are: %s", ip, this.peers.keySet());
  79     }
  80
  81     @Override
  82     public synchronized BGPSessionListener getPeer(final IpAddress ip,
  83         final Ipv4Address sourceId, final Ipv4Address remoteId)
  84             throws BGPDocumentedException {
  85         Preconditions.checkNotNull(ip);
  86         Preconditions.checkNotNull(sourceId);
  87         Preconditions.checkNotNull(remoteId);
  88
  89         checkPeerConfigured(ip);
  90
  91         final BGPSessionId currentConnection = new BGPSessionId(sourceId, remoteId);
  92
  93         if (this.sessionIds.containsKey(ip)) {
  94             LOG.warn("Duplicate BGP session established with {}", ip);
  95
  96             final BGPSessionId previousConnection = this.sessionIds.get(ip);
  97
  98             // Session reestablished with different ids
  99             if (!previousConnection.equals(currentConnection)) {
 100                 LOG.warn("BGP session with {} {} has to be dropped. Same session already present {}", ip, currentConnection, previousConnection);
 101                 throw new BGPDocumentedException(
 102                     String.format("BGP session with %s %s has to be dropped. Same session already present %s",
 103                         ip, currentConnection, previousConnection),
 104                         BGPError.CONNECTION_COLLISION_RESOLUTION);
 105
 106                 // Session reestablished with lower source bgp id, dropping current
 107             } else if (previousConnection.isHigherDirection(currentConnection)) {
 108                 LOG.warn("BGP session with {} {} has to be dropped. Opposite session already present", ip, currentConnection);
 109                 throw new BGPDocumentedException(
 110                     String.format("BGP session with %s initiated %s has to be dropped. Opposite session already present",
 111                         ip, currentConnection),
 112                         BGPError.CONNECTION_COLLISION_RESOLUTION);
 113
 114                 // Session reestablished with higher source bgp id, dropping previous
 115             } else if (currentConnection.isHigherDirection(previousConnection)) {
 116                 LOG.warn("BGP session with {} {} released. Replaced by opposite session", ip, previousConnection);
 117                 this.peers.get(ip).releaseConnection();
 118                 return this.peers.get(ip);
 119
 120                 // Session reestablished with same source bgp id, dropping current as duplicate
 121             } else {
 122                 LOG.warn("BGP session with %s initiated from %s to %s has to be dropped. Same session already present", ip, sourceId, remoteId);
 123                 throw new BGPDocumentedException(
 124                     String.format("BGP session with %s initiated %s has to be dropped. Same session already present",
 125                         ip, currentConnection),
 126                         BGPError.CONNECTION_COLLISION_RESOLUTION);
 127             }
 128         }
 129
 130         // Map session id to peer IP address
 131         this.sessionIds.put(ip, currentConnection);
 132         return this.peers.get(ip);
 133     }
 134
 135     @Override
 136     public BGPSessionPreferences getPeerPreferences(final IpAddress ip) {
 137         Preconditions.checkNotNull(ip);
 138         checkPeerConfigured(ip);
 139         return this.peerPreferences.get(ip);
 140     }
 141
 142     /**
 143      * Create IpAddress from SocketAddress. Only InetSocketAddress is accepted with inner address: Inet4Address and Inet6Address.
 144      *
 145      * @throws IllegalArgumentException if submitted socket address is not InetSocketAddress[ipv4 | ipv6]
 146      * @param socketAddress socket address to transform
 147      */
 148     public static IpAddress getIpAddress(final SocketAddress socketAddress) {
 149         Preconditions.checkNotNull(socketAddress);
 150         Preconditions.checkArgument(socketAddress instanceof InetSocketAddress, "Expecting InetSocketAddress but was %s", socketAddress.getClass());
 151         final InetAddress inetAddress = ((InetSocketAddress) socketAddress).getAddress();
 152
 153         if(inetAddress instanceof Inet4Address) {
 154             return new IpAddress(new Ipv4Address(inetAddress.getHostAddress()));
 155         } else if(inetAddress instanceof Inet6Address) {
 156             return new IpAddress(new Ipv6Address(inetAddress.getHostAddress()));
 157         }
 158
 159         throw new IllegalArgumentException("Expecting " + Inet4Address.class + " or " + Inet6Address.class + " but was " + inetAddress.getClass());
 160     }
 161
 162     @Override
 163     public synchronized void close() {
 164         this.peers.clear();
 165         this.sessionIds.clear();
 166     }
 167
 168     @Override
 169     public String toString() {
 170         return Objects.toStringHelper(this)
 171             .add("peers", this.peers.keySet())
 172             .toString();
 173     }
 174
 175     /**
 176      * Session identifier that contains (source Bgp Id) -> (destination Bgp Id)
 177      */
 178     private static final class BGPSessionId {
 179         private final Ipv4Address from, to;
 180
 181         BGPSessionId(final Ipv4Address from, final Ipv4Address to) {
 182             this.from = Preconditions.checkNotNull(from);
 183             this.to = Preconditions.checkNotNull(to);
 184         }
 185
 186         /**
 187          * Equals does not take direction of connection into account id1 -> id2 and id2 -> id1 are equal
 188          */
 189         @Override
 190         public boolean equals(final Object o) {
 191             if (this == o) {
 192                 return true;
 193             }
 194             if (o == null || getClass() != o.getClass()) {
 195                 return false;
 196             }
 197
 198             final BGPSessionId bGPSessionId = (BGPSessionId) o;
 199
 200             if (!this.from.equals(bGPSessionId.from) && !this.from.equals(bGPSessionId.to)) {
 201                 return false;
 202             }
 203             if (!this.to.equals(bGPSessionId.to) && !this.to.equals(bGPSessionId.from)) {
 204                 return false;
 205             }
 206
 207             return true;
 208         }
 209
 210         @Override
 211         public int hashCode() {
 212             final int prime = 31;
 213             int result = this.from.hashCode() + this.to.hashCode();
 214             result = prime * result;
 215             return result;
 216         }
 217
 218         /**
 219          * Check if this connection is equal to other and if it contains higher source bgp id
 220          */
 221         boolean isHigherDirection(final BGPSessionId other) {
 222             Preconditions.checkState(!this.isSameDirection(other), "Equal sessions with same direction");
 223             return toLong(this.from) > toLong(other.from);
 224         }
 225
 226         private long toLong(final Ipv4Address from) {
 227             return Long.parseLong(NONDIGIT.removeFrom(from.getValue()));
 228         }
 229
 230         /**
 231          * Check if 2 connections are equal and face same direction
 232          */
 233         boolean isSameDirection(final BGPSessionId other) {
 234             Preconditions.checkState(this.equals(other), "Only equal sessions can be compared");
 235             return this.from.equals(other.from);
 236         }
 237
 238         @Override
 239         public String toString() {
 240             return Objects.toStringHelper(this)
 241                 .add("from", this.from)
 242                 .add("to", this.to)
 243                 .toString();
 244         }
 245     }
 246 }