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