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
  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
  23 import javax.annotation.concurrent.GuardedBy;
  24 import javax.annotation.concurrent.ThreadSafe;
  25
  26 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  27 import org.opendaylight.protocol.bgp.parser.BGPError;
  28 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
  29 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  30 import org.opendaylight.protocol.bgp.rib.impl.spi.ReusableBGPPeer;
  31 import org.opendaylight.protocol.bgp.rib.spi.BGPSessionListener;
  32 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.IpAddress;
  33 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
  34 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv6Address;
  35 import org.slf4j.Logger;
  36 import org.slf4j.LoggerFactory;
  37
  38 /**
  39  * BGP peer registry that allows only 1 session per BGP peer.
  40  * If second session with peer is established, one of the sessions will be dropped.
  41  * The session with lower source BGP id will be dropped.
  42  */
  43 @ThreadSafe
  44 public final class StrictBGPPeerRegistry implements BGPPeerRegistry {
  45
  46     private static final Logger LOG = LoggerFactory.getLogger(StrictBGPPeerRegistry.class);
  47
  48     private static final CharMatcher NONDIGIT = CharMatcher.inRange('0', '9').negate();
  49
  50     // TODO remove backwards compatibility
  51     public static final StrictBGPPeerRegistry GLOBAL = new StrictBGPPeerRegistry();
  52
  53     @GuardedBy("this")
  54     private final Map<IpAddress, ReusableBGPPeer> peers = Maps.newHashMap();
  55     @GuardedBy("this")
  56     private final Map<IpAddress, BGPSessionId> sessionIds = Maps.newHashMap();
  57     @GuardedBy("this")
  58     private final Map<IpAddress, BGPSessionPreferences> peerPreferences = Maps.newHashMap();
  59
  60     @Override
  61     public synchronized void addPeer(final IpAddress ip, final ReusableBGPPeer peer, final BGPSessionPreferences preferences) {
  62         Preconditions.checkNotNull(ip);
  63         Preconditions.checkArgument(!this.peers.containsKey(ip), "Peer for %s already present", ip);
  64         this.peers.put(ip, Preconditions.checkNotNull(peer));
  65         this.peerPreferences.put(ip, Preconditions.checkNotNull(preferences));
  66     }
  67
  68     @Override
  69     public synchronized void removePeer(final IpAddress ip) {
  70         Preconditions.checkNotNull(ip);
  71         this.peers.remove(ip);
  72     }
  73
  74     @Override
  75     public boolean isPeerConfigured(final IpAddress ip) {
  76         Preconditions.checkNotNull(ip);
  77         return this.peers.containsKey(ip);
  78     }
  79
  80     private void checkPeerConfigured(final IpAddress ip) {
  81         Preconditions.checkState(isPeerConfigured(ip), "BGP peer with ip: %s not configured, configured peers are: %s", ip, this.peers.keySet());
  82     }
  83
  84     @Override
  85     public synchronized BGPSessionListener getPeer(final IpAddress ip,
  86         final Ipv4Address sourceId, final Ipv4Address remoteId)
  87             throws BGPDocumentedException {
  88         Preconditions.checkNotNull(ip);
  89         Preconditions.checkNotNull(sourceId);
  90         Preconditions.checkNotNull(remoteId);
  91
  92         checkPeerConfigured(ip);
  93
  94         final BGPSessionId currentConnection = new BGPSessionId(sourceId, remoteId);
  95
  96         if (this.sessionIds.containsKey(ip)) {
  97             LOG.warn("Duplicate BGP session established with {}", ip);
  98
  99             final BGPSessionId previousConnection = this.sessionIds.get(ip);
 100
 101             // Session reestablished with different ids
 102             if (!previousConnection.equals(currentConnection)) {
 103                 LOG.warn("BGP session with {} {} has to be dropped. Same session already present {}", ip, currentConnection, previousConnection);
 104                 throw new BGPDocumentedException(
 105                     String.format("BGP session with %s %s has to be dropped. Same session already present %s",
 106                         ip, currentConnection, previousConnection),
 107                         BGPError.CEASE);
 108
 109                 // Session reestablished with lower source bgp id, dropping current
 110             } else if (previousConnection.isHigherDirection(currentConnection)) {
 111                 LOG.warn("BGP session with {} {} has to be dropped. Opposite session already present", ip, currentConnection);
 112                 throw new BGPDocumentedException(
 113                     String.format("BGP session with %s initiated %s has to be dropped. Opposite session already present",
 114                         ip, currentConnection),
 115                         BGPError.CEASE);
 116
 117                 // Session reestablished with higher source bgp id, dropping previous
 118             } else if (currentConnection.isHigherDirection(previousConnection)) {
 119                 LOG.warn("BGP session with {} {} released. Replaced by opposite session", ip, previousConnection);
 120                 this.peers.get(ip).releaseConnection();
 121                 return this.peers.get(ip);
 122
 123                 // Session reestablished with same source bgp id, dropping current as duplicate
 124             } else {
 125                 LOG.warn("BGP session with %s initiated from %s to %s has to be dropped. Same session already present", ip, sourceId, remoteId);
 126                 throw new BGPDocumentedException(
 127                     String.format("BGP session with %s initiated %s has to be dropped. Same session already present",
 128                         ip, currentConnection),
 129                         BGPError.CEASE);
 130             }
 131         }
 132
 133         // Map session id to peer IP address
 134         this.sessionIds.put(ip, currentConnection);
 135         return this.peers.get(ip);
 136     }
 137
 138     @Override
 139     public BGPSessionPreferences getPeerPreferences(final IpAddress ip) {
 140         Preconditions.checkNotNull(ip);
 141         checkPeerConfigured(ip);
 142         return this.peerPreferences.get(ip);
 143     }
 144
 145     /**
 146      * Create IpAddress from SocketAddress. Only InetSocketAddress is accepted with inner address: Inet4Address and Inet6Address.
 147      *
 148      * @throws IllegalArgumentException if submitted socket address is not InetSocketAddress[ipv4 | ipv6]
 149      * @param socketAddress socket address to transform
 150      */
 151     public static IpAddress getIpAddress(final SocketAddress socketAddress) {
 152         Preconditions.checkNotNull(socketAddress);
 153         Preconditions.checkArgument(socketAddress instanceof InetSocketAddress, "Expecting InetSocketAddress but was %s", socketAddress.getClass());
 154         final InetAddress inetAddress = ((InetSocketAddress) socketAddress).getAddress();
 155
 156         if(inetAddress instanceof Inet4Address) {
 157             return new IpAddress(new Ipv4Address(inetAddress.getHostAddress()));
 158         } else if(inetAddress instanceof Inet6Address) {
 159             return new IpAddress(new Ipv6Address(inetAddress.getHostAddress()));
 160         }
 161
 162         throw new IllegalArgumentException("Expecting " + Inet4Address.class + " or " + Inet6Address.class + " but was " + inetAddress.getClass());
 163     }
 164
 165     @Override
 166     public synchronized void close() {
 167         this.peers.clear();
 168         this.sessionIds.clear();
 169     }
 170
 171     @Override
 172     public String toString() {
 173         return Objects.toStringHelper(this)
 174             .add("peers", this.peers.keySet())
 175             .toString();
 176     }
 177
 178     /**
 179      * Session identifier that contains (source Bgp Id) -> (destination Bgp Id)
 180      */
 181     private static final class BGPSessionId {
 182         private final Ipv4Address from, to;
 183
 184         BGPSessionId(final Ipv4Address from, final Ipv4Address to) {
 185             this.from = Preconditions.checkNotNull(from);
 186             this.to = Preconditions.checkNotNull(to);
 187         }
 188
 189         /**
 190          * Equals does not take direction of connection into account id1 -> id2 and id2 -> id1 are equal
 191          */
 192         @Override
 193         public boolean equals(final Object o) {
 194             if (this == o) {
 195                 return true;
 196             }
 197             if (o == null || getClass() != o.getClass()) {
 198                 return false;
 199             }
 200
 201             final BGPSessionId bGPSessionId = (BGPSessionId) o;
 202
 203             if (!this.from.equals(bGPSessionId.from) && !this.from.equals(bGPSessionId.to)) {
 204                 return false;
 205             }
 206             if (!this.to.equals(bGPSessionId.to) && !this.to.equals(bGPSessionId.from)) {
 207                 return false;
 208             }
 209
 210             return true;
 211         }
 212
 213         @Override
 214         public int hashCode() {
 215             final int prime = 31;
 216             int result = this.from.hashCode() + this.to.hashCode();
 217             result = prime * result;
 218             return result;
 219         }
 220
 221         /**
 222          * Check if this connection is equal to other and if it contains higher source bgp id
 223          */
 224         boolean isHigherDirection(final BGPSessionId other) {
 225             Preconditions.checkState(!this.isSameDirection(other), "Equal sessions with same direction");
 226             return toLong(this.from) > toLong(other.from);
 227         }
 228
 229         private long toLong(final Ipv4Address from) {
 230             return Long.parseLong(NONDIGIT.removeFrom(from.getValue()));
 231         }
 232
 233         /**
 234          * Check if 2 connections are equal and face same direction
 235          */
 236         boolean isSameDirection(final BGPSessionId other) {
 237             Preconditions.checkState(this.equals(other), "Only equal sessions can be compared");
 238             return this.from.equals(other.from);
 239         }
 240
 241         @Override
 242         public String toString() {
 243             return Objects.toStringHelper(this)
 244                 .add("from", this.from)
 245                 .add("to", this.to)
 246                 .toString();
 247         }
 248     }
 249 }