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.MoreObjects;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.collect.Maps;
  14 import com.google.common.net.InetAddresses;
  15 import com.google.common.primitives.UnsignedInts;
  16 import java.net.Inet4Address;
  17 import java.net.Inet6Address;
  18 import java.net.InetAddress;
  19 import java.net.InetSocketAddress;
  20 import java.net.SocketAddress;
  21 import java.util.Map;
  22 import javax.annotation.concurrent.GuardedBy;
  23 import javax.annotation.concurrent.ThreadSafe;
  24 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  25 import org.opendaylight.protocol.bgp.parser.BGPError;
  26 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
  27 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  28 import org.opendaylight.protocol.bgp.rib.impl.spi.ReusableBGPPeer;
  29 import org.opendaylight.protocol.bgp.rib.spi.BGPSessionListener;
  30 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.AsNumber;
  31 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.IpAddress;
  32 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
  33 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv6Address;
  34 import org.slf4j.Logger;
  35 import org.slf4j.LoggerFactory;
  36
  37 /**
  38  * BGP peer registry that allows only 1 session per BGP peer.
  39  * If second session with peer is established, one of the sessions will be dropped.
  40  * The session with lower source BGP id will be dropped.
  41  */
  42 @ThreadSafe
  43 public final class StrictBGPPeerRegistry implements BGPPeerRegistry {
  44
  45     private static final Logger LOG = LoggerFactory.getLogger(StrictBGPPeerRegistry.class);
  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 synchronized void removePeerSession(final IpAddress ip) {
  73         Preconditions.checkNotNull(ip);
  74         this.sessionIds.remove(ip);
  75     }
  76
  77     @Override
  78     public boolean isPeerConfigured(final IpAddress ip) {
  79         Preconditions.checkNotNull(ip);
  80         return this.peers.containsKey(ip);
  81     }
  82
  83     private void checkPeerConfigured(final IpAddress ip) {
  84         Preconditions.checkState(isPeerConfigured(ip), "BGP peer with ip: %s not configured, configured peers are: %s", ip, this.peers.keySet());
  85     }
  86
  87     @Override
  88     public synchronized BGPSessionListener getPeer(final IpAddress ip,
  89         final Ipv4Address sourceId, final Ipv4Address remoteId, final AsNumber asNumber)
  90             throws BGPDocumentedException {
  91         Preconditions.checkNotNull(ip);
  92         Preconditions.checkNotNull(sourceId);
  93         Preconditions.checkNotNull(remoteId);
  94
  95         checkPeerConfigured(ip);
  96
  97         final BGPSessionId currentConnection = new BGPSessionId(sourceId, remoteId, asNumber);
  98         final BGPSessionListener p = this.peers.get(ip);
  99
 100         final BGPSessionId previousConnection = this.sessionIds.get(ip);
 101
 102         if (previousConnection != null) {
 103
 104             LOG.warn("Duplicate BGP session established with {}", ip);
 105
 106             // Session reestablished with different ids
 107             if (!previousConnection.equals(currentConnection)) {
 108                 LOG.warn("BGP session with {} {} has to be dropped. Same session already present {}", ip, currentConnection, previousConnection);
 109                 throw new BGPDocumentedException(
 110                     String.format("BGP session with %s %s has to be dropped. Same session already present %s",
 111                         ip, currentConnection, previousConnection),
 112                         BGPError.CEASE);
 113
 114                 // Session reestablished with lower source bgp id, dropping current
 115             } else if (previousConnection.isHigherDirection(currentConnection)) {
 116                 LOG.warn("BGP session with {} {} has to be dropped. Opposite session already present", ip, currentConnection);
 117                 throw new BGPDocumentedException(
 118                     String.format("BGP session with %s initiated %s has to be dropped. Opposite session already present",
 119                         ip, currentConnection),
 120                         BGPError.CEASE);
 121
 122                 // Session reestablished with higher source bgp id, dropping previous
 123             } else if (currentConnection.isHigherDirection(previousConnection)) {
 124                 LOG.warn("BGP session with {} {} released. Replaced by opposite session", ip, previousConnection);
 125                 this.peers.get(ip).releaseConnection();
 126                 return this.peers.get(ip);
 127
 128             } else if (previousConnection.hasHigherAsNumber(currentConnection)) {
 129                 LOG.warn("BGP session with {} {} has to be dropped. Opposite session already present", ip, currentConnection);
 130                 throw new BGPDocumentedException(
 131                     String.format("BGP session with %s initiated %s has to be dropped. Opposite session already present",
 132                         ip, currentConnection),
 133                         BGPError.CEASE);
 134             } else if (currentConnection.hasHigherAsNumber(previousConnection)) {
 135                 LOG.warn("BGP session with {} {} released. Replaced by opposite session", ip, previousConnection);
 136                 this.peers.get(ip).releaseConnection();
 137                 return this.peers.get(ip);
 138             // Session reestablished with same source bgp id, dropping current as duplicate
 139             } else {
 140                 LOG.warn("BGP session with %s initiated from %s to %s has to be dropped. Same session already present", ip, sourceId, remoteId);
 141                 throw new BGPDocumentedException(
 142                     String.format("BGP session with %s initiated %s has to be dropped. Same session already present",
 143                         ip, currentConnection),
 144                         BGPError.CEASE);
 145             }
 146         }
 147
 148         // Map session id to peer IP address
 149         this.sessionIds.put(ip, currentConnection);
 150         return p;
 151     }
 152
 153     @Override
 154     public BGPSessionPreferences getPeerPreferences(final IpAddress ip) {
 155         Preconditions.checkNotNull(ip);
 156         checkPeerConfigured(ip);
 157         return this.peerPreferences.get(ip);
 158     }
 159
 160     /**
 161      * Creates IpAddress from SocketAddress. Only InetSocketAddress is accepted with inner address: Inet4Address and Inet6Address.
 162      *
 163      * @param socketAddress socket address to transform
 164      * @throws IllegalArgumentException if submitted socket address is not InetSocketAddress[ipv4 | ipv6]
 165      */
 166     public static IpAddress getIpAddress(final SocketAddress socketAddress) {
 167         Preconditions.checkNotNull(socketAddress);
 168         Preconditions.checkArgument(socketAddress instanceof InetSocketAddress, "Expecting InetSocketAddress but was %s", socketAddress.getClass());
 169         final InetAddress inetAddress = ((InetSocketAddress) socketAddress).getAddress();
 170
 171         if(inetAddress instanceof Inet4Address) {
 172             return new IpAddress(new Ipv4Address(inetAddress.getHostAddress()));
 173         } else if(inetAddress instanceof Inet6Address) {
 174             return new IpAddress(new Ipv6Address(inetAddress.getHostAddress()));
 175         }
 176
 177         throw new IllegalArgumentException("Expecting " + Inet4Address.class + " or " + Inet6Address.class + " but was " + inetAddress.getClass());
 178     }
 179
 180     @Override
 181     public synchronized void close() {
 182         this.peers.clear();
 183         this.sessionIds.clear();
 184     }
 185
 186     @Override
 187     public String toString() {
 188         return MoreObjects.toStringHelper(this)
 189             .add("peers", this.peers.keySet())
 190             .toString();
 191     }
 192
 193     /**
 194      * Session identifier that contains (source Bgp Id) -> (destination Bgp Id)
 195      */
 196     private static final class BGPSessionId {
 197
 198         private final Ipv4Address from, to;
 199         private final AsNumber asNumber;
 200
 201         BGPSessionId(final Ipv4Address from, final Ipv4Address to, final AsNumber asNumber) {
 202             this.from = Preconditions.checkNotNull(from);
 203             this.to = Preconditions.checkNotNull(to);
 204             this.asNumber = Preconditions.checkNotNull(asNumber);
 205         }
 206
 207         /**
 208          * Equals does not take direction of connection into account id1 -> id2 and id2 -> id1 are equal
 209          */
 210         @Override
 211         public boolean equals(final Object o) {
 212             if (this == o) {
 213                 return true;
 214             }
 215             if (o == null || getClass() != o.getClass()) {
 216                 return false;
 217             }
 218
 219             final BGPSessionId bGPSessionId = (BGPSessionId) o;
 220
 221             if (!this.from.equals(bGPSessionId.from) && !this.from.equals(bGPSessionId.to)) {
 222                 return false;
 223             }
 224             if (!this.to.equals(bGPSessionId.to) && !this.to.equals(bGPSessionId.from)) {
 225                 return false;
 226             }
 227
 228             return true;
 229         }
 230
 231         @Override
 232         public int hashCode() {
 233             final int prime = 31;
 234             int result = this.from.hashCode() + this.to.hashCode();
 235             result = prime * result;
 236             return result;
 237         }
 238
 239         /**
 240          * Check if this connection is equal to other and if it contains higher source bgp id
 241          */
 242         boolean isHigherDirection(final BGPSessionId other) {
 243             return toLong(this.from) > toLong(other.from);
 244         }
 245
 246         boolean hasHigherAsNumber(final BGPSessionId other) {
 247             return this.asNumber.getValue() > other.asNumber.getValue();
 248         }
 249
 250         private long toLong(final Ipv4Address from) {
 251             final int i = InetAddresses.coerceToInteger(InetAddresses.forString(from.getValue()));
 252             return UnsignedInts.toLong(i);
 253         }
 254
 255         @Override
 256         public String toString() {
 257             return MoreObjects.toStringHelper(this)
 258                 .add("from", this.from)
 259                 .add("to", this.to)
 260                 .toString();
 261         }
 262     }
 263 }