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     public synchronized void removePeerSession(final IpAddress ip) {
  72         Preconditions.checkNotNull(ip);
  73         this.sessionIds.remove(ip);
  74     }
  75
  76     @Override
  77     public boolean isPeerConfigured(final IpAddress ip) {
  78         Preconditions.checkNotNull(ip);
  79         return this.peers.containsKey(ip);
  80     }
  81
  82     private void checkPeerConfigured(final IpAddress ip) {
  83         Preconditions.checkState(isPeerConfigured(ip), "BGP peer with ip: %s not configured, configured peers are: %s", ip, this.peers.keySet());
  84     }
  85
  86     @Override
  87     public synchronized BGPSessionListener getPeer(final IpAddress ip,
  88         final Ipv4Address sourceId, final Ipv4Address remoteId)
  89             throws BGPDocumentedException {
  90         Preconditions.checkNotNull(ip);
  91         Preconditions.checkNotNull(sourceId);
  92         Preconditions.checkNotNull(remoteId);
  93
  94         checkPeerConfigured(ip);
  95
  96         final BGPSessionId currentConnection = new BGPSessionId(sourceId, remoteId);
  97
  98         if (this.sessionIds.containsKey(ip)) {
  99             LOG.warn("Duplicate BGP session established with {}", ip);
 100
 101             final BGPSessionId previousConnection = this.sessionIds.get(ip);
 102
 103             // Session reestablished with different ids
 104             if (!previousConnection.equals(currentConnection)) {
 105                 LOG.warn("BGP session with {} {} has to be dropped. Same session already present {}", ip, currentConnection, previousConnection);
 106                 throw new BGPDocumentedException(
 107                     String.format("BGP session with %s %s has to be dropped. Same session already present %s",
 108                         ip, currentConnection, previousConnection),
 109                         BGPError.CEASE);
 110
 111                 // Session reestablished with lower source bgp id, dropping current
 112             } else if (previousConnection.isHigherDirection(currentConnection)) {
 113                 LOG.warn("BGP session with {} {} has to be dropped. Opposite session already present", ip, currentConnection);
 114                 throw new BGPDocumentedException(
 115                     String.format("BGP session with %s initiated %s has to be dropped. Opposite session already present",
 116                         ip, currentConnection),
 117                         BGPError.CEASE);
 118
 119                 // Session reestablished with higher source bgp id, dropping previous
 120             } else if (currentConnection.isHigherDirection(previousConnection)) {
 121                 LOG.warn("BGP session with {} {} released. Replaced by opposite session", ip, previousConnection);
 122                 this.peers.get(ip).releaseConnection();
 123                 return this.peers.get(ip);
 124
 125                 // Session reestablished with same source bgp id, dropping current as duplicate
 126             } else {
 127                 LOG.warn("BGP session with %s initiated from %s to %s has to be dropped. Same session already present", ip, sourceId, remoteId);
 128                 throw new BGPDocumentedException(
 129                     String.format("BGP session with %s initiated %s has to be dropped. Same session already present",
 130                         ip, currentConnection),
 131                         BGPError.CEASE);
 132             }
 133         }
 134
 135         // Map session id to peer IP address
 136         this.sessionIds.put(ip, currentConnection);
 137         return this.peers.get(ip);
 138     }
 139
 140     @Override
 141     public BGPSessionPreferences getPeerPreferences(final IpAddress ip) {
 142         Preconditions.checkNotNull(ip);
 143         checkPeerConfigured(ip);
 144         return this.peerPreferences.get(ip);
 145     }
 146
 147     /**
 148      * Create IpAddress from SocketAddress. Only InetSocketAddress is accepted with inner address: Inet4Address and Inet6Address.
 149      *
 150      * @throws IllegalArgumentException if submitted socket address is not InetSocketAddress[ipv4 | ipv6]
 151      * @param socketAddress socket address to transform
 152      */
 153     public static IpAddress getIpAddress(final SocketAddress socketAddress) {
 154         Preconditions.checkNotNull(socketAddress);
 155         Preconditions.checkArgument(socketAddress instanceof InetSocketAddress, "Expecting InetSocketAddress but was %s", socketAddress.getClass());
 156         final InetAddress inetAddress = ((InetSocketAddress) socketAddress).getAddress();
 157
 158         if(inetAddress instanceof Inet4Address) {
 159             return new IpAddress(new Ipv4Address(inetAddress.getHostAddress()));
 160         } else if(inetAddress instanceof Inet6Address) {
 161             return new IpAddress(new Ipv6Address(inetAddress.getHostAddress()));
 162         }
 163
 164         throw new IllegalArgumentException("Expecting " + Inet4Address.class + " or " + Inet6Address.class + " but was " + inetAddress.getClass());
 165     }
 166
 167     @Override
 168     public synchronized void close() {
 169         this.peers.clear();
 170         this.sessionIds.clear();
 171     }
 172
 173     @Override
 174     public String toString() {
 175         return Objects.toStringHelper(this)
 176             .add("peers", this.peers.keySet())
 177             .toString();
 178     }
 179
 180     /**
 181      * Session identifier that contains (source Bgp Id) -> (destination Bgp Id)
 182      */
 183     private static final class BGPSessionId {
 184         private final Ipv4Address from, to;
 185
 186         BGPSessionId(final Ipv4Address from, final Ipv4Address to) {
 187             this.from = Preconditions.checkNotNull(from);
 188             this.to = Preconditions.checkNotNull(to);
 189         }
 190
 191         /**
 192          * Equals does not take direction of connection into account id1 -> id2 and id2 -> id1 are equal
 193          */
 194         @Override
 195         public boolean equals(final Object o) {
 196             if (this == o) {
 197                 return true;
 198             }
 199             if (o == null || getClass() != o.getClass()) {
 200                 return false;
 201             }
 202
 203             final BGPSessionId bGPSessionId = (BGPSessionId) o;
 204
 205             if (!this.from.equals(bGPSessionId.from) && !this.from.equals(bGPSessionId.to)) {
 206                 return false;
 207             }
 208             if (!this.to.equals(bGPSessionId.to) && !this.to.equals(bGPSessionId.from)) {
 209                 return false;
 210             }
 211
 212             return true;
 213         }
 214
 215         @Override
 216         public int hashCode() {
 217             final int prime = 31;
 218             int result = this.from.hashCode() + this.to.hashCode();
 219             result = prime * result;
 220             return result;
 221         }
 222
 223         /**
 224          * Check if this connection is equal to other and if it contains higher source bgp id
 225          */
 226         boolean isHigherDirection(final BGPSessionId other) {
 227             Preconditions.checkState(!this.isSameDirection(other), "Equal sessions with same direction");
 228             return toLong(this.from) > toLong(other.from);
 229         }
 230
 231         private long toLong(final Ipv4Address from) {
 232             return Long.parseLong(NONDIGIT.removeFrom(from.getValue()));
 233         }
 234
 235         /**
 236          * Check if 2 connections are equal and face same direction
 237          */
 238         boolean isSameDirection(final BGPSessionId other) {
 239             Preconditions.checkState(this.equals(other), "Only equal sessions can be compared");
 240             return this.from.equals(other.from);
 241         }
 242
 243         @Override
 244         public String toString() {
 245             return Objects.toStringHelper(this)
 246                 .add("from", this.from)
 247                 .add("to", this.to)
 248                 .toString();
 249         }
 250     }
 251 }