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         Preconditions.checkNotNull(preferences.getMyAs());
  63         Preconditions.checkNotNull(preferences.getHoldTime());
  64         Preconditions.checkNotNull(preferences.getParams());
  65         Preconditions.checkNotNull(preferences.getBgpId());
  66         this.peerPreferences.put(ip, preferences);
  67     }
  68
  69     @Override
  70     public synchronized void removePeer(final IpAddress ip) {
  71         Preconditions.checkNotNull(ip);
  72         this.peers.remove(ip);
  73     }
  74
  75     @Override
  76     public synchronized void removePeerSession(final IpAddress ip) {
  77         Preconditions.checkNotNull(ip);
  78         this.sessionIds.remove(ip);
  79     }
  80
  81     @Override
  82     public boolean isPeerConfigured(final IpAddress ip) {
  83         Preconditions.checkNotNull(ip);
  84         return this.peers.containsKey(ip);
  85     }
  86
  87     private void checkPeerConfigured(final IpAddress ip) {
  88         Preconditions.checkState(isPeerConfigured(ip), "BGP peer with ip: %s not configured, configured peers are: %s", ip, this.peers.keySet());
  89     }
  90
  91     @Override
  92     public synchronized BGPSessionListener getPeer(final IpAddress ip, final Ipv4Address sourceId,
  93         final Ipv4Address remoteId, final AsNumber asNumber) throws BGPDocumentedException {
  94         Preconditions.checkNotNull(ip);
  95         Preconditions.checkNotNull(sourceId);
  96         Preconditions.checkNotNull(remoteId);
  97         Preconditions.checkNotNull(asNumber);
  98
  99         checkPeerConfigured(ip);
 100
 101         final BGPSessionId currentConnection = new BGPSessionId(sourceId, remoteId, asNumber);
 102         final BGPSessionListener p = this.peers.get(ip);
 103
 104         final BGPSessionId previousConnection = this.sessionIds.get(ip);
 105
 106         if (previousConnection != null) {
 107
 108             LOG.warn("Duplicate BGP session established with {}", ip);
 109
 110             // Session reestablished with different ids
 111             if (!previousConnection.equals(currentConnection)) {
 112                 LOG.warn("BGP session with {} {} has to be dropped. Same session already present {}", ip, currentConnection, previousConnection);
 113                 throw new BGPDocumentedException(
 114                     String.format("BGP session with %s %s has to be dropped. Same session already present %s",
 115                         ip, currentConnection, previousConnection),
 116                         BGPError.CEASE);
 117
 118                 // Session reestablished with lower source bgp id, dropping current
 119             } else if (previousConnection.isHigherDirection(currentConnection)) {
 120                 LOG.warn("BGP session with {} {} has to be dropped. Opposite session already present", ip, currentConnection);
 121                 throw new BGPDocumentedException(
 122                     String.format("BGP session with %s initiated %s has to be dropped. Opposite session already present",
 123                         ip, currentConnection),
 124                         BGPError.CEASE);
 125
 126                 // Session reestablished with higher source bgp id, dropping previous
 127             } else if (currentConnection.isHigherDirection(previousConnection)) {
 128                 LOG.warn("BGP session with {} {} released. Replaced by opposite session", ip, previousConnection);
 129                 this.peers.get(ip).releaseConnection();
 130                 return this.peers.get(ip);
 131
 132             } else if (previousConnection.hasHigherAsNumber(currentConnection)) {
 133                 LOG.warn("BGP session with {} {} has to be dropped. Opposite session already present", ip, currentConnection);
 134                 throw new BGPDocumentedException(
 135                     String.format("BGP session with %s initiated %s has to be dropped. Opposite session already present",
 136                         ip, currentConnection),
 137                         BGPError.CEASE);
 138             } else if (currentConnection.hasHigherAsNumber(previousConnection)) {
 139                 LOG.warn("BGP session with {} {} released. Replaced by opposite session", ip, previousConnection);
 140                 this.peers.get(ip).releaseConnection();
 141                 return this.peers.get(ip);
 142             // Session reestablished with same source bgp id, dropping current as duplicate
 143             } else {
 144                 LOG.warn("BGP session with %s initiated from %s to %s has to be dropped. Same session already present", ip, sourceId, remoteId);
 145                 throw new BGPDocumentedException(
 146                     String.format("BGP session with %s initiated %s has to be dropped. Same session already present",
 147                         ip, currentConnection),
 148                         BGPError.CEASE);
 149             }
 150         } else {
 151             if (!getPeerPreferences(ip).getMyAs().equals(asNumber)) {
 152                 LOG.warn("Unexpected remote AS number. Expecting {}, got {}", getPeerPreferences(ip).getMyAs(), asNumber);
 153                 throw new BGPDocumentedException("Peer AS number mismatch", BGPError.BAD_PEER_AS);
 154             }
 155         }
 156
 157         // Map session id to peer IP address
 158         this.sessionIds.put(ip, currentConnection);
 159         return p;
 160     }
 161
 162     @Override
 163     public BGPSessionPreferences getPeerPreferences(final IpAddress ip) {
 164         Preconditions.checkNotNull(ip);
 165         checkPeerConfigured(ip);
 166         return this.peerPreferences.get(ip);
 167     }
 168
 169     /**
 170      * Creates IpAddress from SocketAddress. Only InetSocketAddress is accepted with inner address: Inet4Address and Inet6Address.
 171      *
 172      * @param socketAddress socket address to transform
 173      * @return IpAddress equivalent to given socket address
 174      * @throws IllegalArgumentException if submitted socket address is not InetSocketAddress[ipv4 | ipv6]
 175      */
 176     public static IpAddress getIpAddress(final SocketAddress socketAddress) {
 177         Preconditions.checkNotNull(socketAddress);
 178         Preconditions.checkArgument(socketAddress instanceof InetSocketAddress, "Expecting InetSocketAddress but was %s", socketAddress.getClass());
 179         final InetAddress inetAddress = ((InetSocketAddress) socketAddress).getAddress();
 180
 181         Preconditions.checkArgument(inetAddress instanceof Inet4Address || inetAddress instanceof Inet6Address, "Expecting %s or %s but was %s", Inet4Address.class, Inet6Address.class, inetAddress.getClass());
 182         if(inetAddress instanceof Inet4Address) {
 183             return new IpAddress(new Ipv4Address(inetAddress.getHostAddress()));
 184         }
 185         return new IpAddress(new Ipv6Address(inetAddress.getHostAddress()));
 186     }
 187
 188     @Override
 189     public synchronized void close() {
 190         this.peers.clear();
 191         this.sessionIds.clear();
 192     }
 193
 194     @Override
 195     public String toString() {
 196         return MoreObjects.toStringHelper(this)
 197             .add("peers", this.peers.keySet())
 198             .toString();
 199     }
 200
 201     /**
 202      * Session identifier that contains (source Bgp Id) -> (destination Bgp Id)
 203      */
 204     private static final class BGPSessionId {
 205
 206         private final Ipv4Address from, to;
 207         private final AsNumber asNumber;
 208
 209         BGPSessionId(final Ipv4Address from, final Ipv4Address to, final AsNumber asNumber) {
 210             this.from = Preconditions.checkNotNull(from);
 211             this.to = Preconditions.checkNotNull(to);
 212             this.asNumber = Preconditions.checkNotNull(asNumber);
 213         }
 214
 215         /**
 216          * Equals does not take direction of connection into account id1 -> id2 and id2 -> id1 are equal
 217          */
 218         @Override
 219         public boolean equals(final Object o) {
 220             if (this == o) {
 221                 return true;
 222             }
 223             if (o == null || getClass() != o.getClass()) {
 224                 return false;
 225             }
 226
 227             final BGPSessionId bGPSessionId = (BGPSessionId) o;
 228
 229             if (!this.from.equals(bGPSessionId.from) && !this.from.equals(bGPSessionId.to)) {
 230                 return false;
 231             }
 232             if (!this.to.equals(bGPSessionId.to) && !this.to.equals(bGPSessionId.from)) {
 233                 return false;
 234             }
 235
 236             return true;
 237         }
 238
 239         @Override
 240         public int hashCode() {
 241             final int prime = 31;
 242             int result = this.from.hashCode() + this.to.hashCode();
 243             result = prime * result;
 244             return result;
 245         }
 246
 247         /**
 248          * Check if this connection is equal to other and if it contains higher source bgp id
 249          */
 250         boolean isHigherDirection(final BGPSessionId other) {
 251             return toLong(this.from) > toLong(other.from);
 252         }
 253
 254         boolean hasHigherAsNumber(final BGPSessionId other) {
 255             return this.asNumber.getValue() > other.asNumber.getValue();
 256         }
 257
 258         private static long toLong(final Ipv4Address from) {
 259             final int i = InetAddresses.coerceToInteger(InetAddresses.forString(from.getValue()));
 260             return UnsignedInts.toLong(i);
 261         }
 262
 263         @Override
 264         public String toString() {
 265             return MoreObjects.toStringHelper(this)
 266                 .add("from", this.from)
 267                 .add("to", this.to)
 268                 .toString();
 269         }
 270     }
 271 }