| /* |
| * Copyright 2014 Open Networking Laboratory |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.onosproject.sdnip.bgp; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| import static org.onlab.util.Tools.namedThreads; |
| |
| import java.net.InetAddress; |
| import java.net.InetSocketAddress; |
| import java.net.SocketAddress; |
| import java.util.Collection; |
| import java.util.LinkedList; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ConcurrentMap; |
| import java.util.concurrent.Executors; |
| |
| import org.jboss.netty.bootstrap.ServerBootstrap; |
| import org.jboss.netty.channel.Channel; |
| import org.jboss.netty.channel.ChannelException; |
| import org.jboss.netty.channel.ChannelFactory; |
| import org.jboss.netty.channel.ChannelPipeline; |
| import org.jboss.netty.channel.ChannelPipelineFactory; |
| import org.jboss.netty.channel.Channels; |
| import org.jboss.netty.channel.group.ChannelGroup; |
| import org.jboss.netty.channel.group.DefaultChannelGroup; |
| import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory; |
| import org.onosproject.sdnip.RouteListener; |
| import org.onosproject.sdnip.RouteUpdate; |
| import org.onlab.packet.Ip4Address; |
| import org.onlab.packet.Ip4Prefix; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * BGP Session Manager class. |
| */ |
| public class BgpSessionManager { |
| private static final Logger log = |
| LoggerFactory.getLogger(BgpSessionManager.class); |
| boolean isShutdown = true; |
| private Channel serverChannel; // Listener for incoming BGP connections |
| private ServerBootstrap serverBootstrap; |
| private ChannelGroup allChannels = new DefaultChannelGroup(); |
| private ConcurrentMap<SocketAddress, BgpSession> bgpSessions = |
| new ConcurrentHashMap<>(); |
| private Ip4Address myBgpId; // Same BGP ID for all peers |
| |
| private BgpRouteSelector bgpRouteSelector = new BgpRouteSelector(); |
| private ConcurrentMap<Ip4Prefix, BgpRouteEntry> bgpRoutes = |
| new ConcurrentHashMap<>(); |
| |
| private final RouteListener routeListener; |
| |
| /** |
| * Constructor for given route listener. |
| * |
| * @param routeListener the route listener to use |
| */ |
| public BgpSessionManager(RouteListener routeListener) { |
| this.routeListener = checkNotNull(routeListener); |
| } |
| |
| /** |
| * Gets the BGP sessions. |
| * |
| * @return the BGP sessions |
| */ |
| public Collection<BgpSession> getBgpSessions() { |
| return bgpSessions.values(); |
| } |
| |
| /** |
| * Gets the BGP routes. |
| * |
| * @return the BGP routes |
| */ |
| public Collection<BgpRouteEntry> getBgpRoutes() { |
| return bgpRoutes.values(); |
| } |
| |
| /** |
| * Adds the channel for a BGP session. |
| * |
| * @param channel the channel to add |
| */ |
| void addSessionChannel(Channel channel) { |
| allChannels.add(channel); |
| } |
| |
| /** |
| * Removes the channel for a BGP session. |
| * |
| * @param channel the channel to remove |
| */ |
| void removeSessionChannel(Channel channel) { |
| allChannels.remove(channel); |
| } |
| |
| /** |
| * Processes the connection from a BGP peer. |
| * |
| * @param bgpSession the BGP session for the peer |
| * @return true if the connection can be established, otherwise false |
| */ |
| boolean peerConnected(BgpSession bgpSession) { |
| |
| // Test whether there is already a session from the same remote |
| if (bgpSessions.get(bgpSession.getRemoteAddress()) != null) { |
| return false; // Duplicate BGP session |
| } |
| bgpSessions.put(bgpSession.getRemoteAddress(), bgpSession); |
| |
| // |
| // If the first connection, set my BGP ID to the local address |
| // of the socket. |
| // |
| if (bgpSession.getLocalAddress() instanceof InetSocketAddress) { |
| InetAddress inetAddr = |
| ((InetSocketAddress) bgpSession.getLocalAddress()).getAddress(); |
| Ip4Address ip4Address = Ip4Address.valueOf(inetAddr.getAddress()); |
| updateMyBgpId(ip4Address); |
| } |
| return true; |
| } |
| |
| /** |
| * Processes the disconnection from a BGP peer. |
| * |
| * @param bgpSession the BGP session for the peer |
| */ |
| void peerDisconnected(BgpSession bgpSession) { |
| bgpSessions.remove(bgpSession.getRemoteAddress()); |
| } |
| |
| /** |
| * Conditionally updates the local BGP ID if it wasn't set already. |
| * <p/> |
| * NOTE: A BGP instance should use same BGP ID across all BGP sessions. |
| * |
| * @param ip4Address the IPv4 address to use as BGP ID |
| */ |
| private synchronized void updateMyBgpId(Ip4Address ip4Address) { |
| if (myBgpId == null) { |
| myBgpId = ip4Address; |
| log.debug("BGP: My BGP ID is {}", myBgpId); |
| } |
| } |
| |
| /** |
| * Gets the local BGP Identifier as an IPv4 address. |
| * |
| * @return the local BGP Identifier as an IPv4 address |
| */ |
| Ip4Address getMyBgpId() { |
| return myBgpId; |
| } |
| |
| /** |
| * Gets the BGP Route Selector. |
| * |
| * @return the BGP Route Selector |
| */ |
| BgpRouteSelector getBgpRouteSelector() { |
| return bgpRouteSelector; |
| } |
| |
| /** |
| * Starts up BGP Session Manager operation. |
| * |
| * @param listenPortNumber the port number to listen on. By default |
| * it should be BgpConstants.BGP_PORT (179) |
| */ |
| public void start(int listenPortNumber) { |
| log.debug("BGP Session Manager start."); |
| isShutdown = false; |
| |
| ChannelFactory channelFactory = |
| new NioServerSocketChannelFactory(Executors.newCachedThreadPool(namedThreads("BGP-SM-boss-%d")), |
| Executors.newCachedThreadPool(namedThreads("BGP-SM-worker-%d"))); |
| ChannelPipelineFactory pipelineFactory = new ChannelPipelineFactory() { |
| @Override |
| public ChannelPipeline getPipeline() throws Exception { |
| // Allocate a new session per connection |
| BgpSession bgpSessionHandler = |
| new BgpSession(BgpSessionManager.this); |
| BgpFrameDecoder bgpFrameDecoder = |
| new BgpFrameDecoder(bgpSessionHandler); |
| |
| // Setup the processing pipeline |
| ChannelPipeline pipeline = Channels.pipeline(); |
| pipeline.addLast("BgpFrameDecoder", bgpFrameDecoder); |
| pipeline.addLast("BgpSession", bgpSessionHandler); |
| return pipeline; |
| } |
| }; |
| InetSocketAddress listenAddress = |
| new InetSocketAddress(listenPortNumber); |
| |
| serverBootstrap = new ServerBootstrap(channelFactory); |
| // serverBootstrap.setOptions("reuseAddr", true); |
| serverBootstrap.setOption("child.keepAlive", true); |
| serverBootstrap.setOption("child.tcpNoDelay", true); |
| serverBootstrap.setPipelineFactory(pipelineFactory); |
| try { |
| serverChannel = serverBootstrap.bind(listenAddress); |
| allChannels.add(serverChannel); |
| } catch (ChannelException e) { |
| log.debug("Exception binding to BGP port {}: ", |
| listenAddress.getPort(), e); |
| } |
| } |
| |
| /** |
| * Stops the BGP Session Manager operation. |
| */ |
| public void stop() { |
| isShutdown = true; |
| allChannels.close().awaitUninterruptibly(); |
| serverBootstrap.releaseExternalResources(); |
| } |
| |
| /** |
| * Class to receive and process the BGP routes from each BGP Session/Peer. |
| */ |
| class BgpRouteSelector { |
| /** |
| * Processes route entry updates: added/updated and deleted route |
| * entries. |
| * |
| * @param bgpSession the BGP session the route entry updates were |
| * received on |
| * @param addedBgpRouteEntries the added/updated route entries to |
| * process |
| * @param deletedBgpRouteEntries the deleted route entries to process |
| */ |
| synchronized void routeUpdates(BgpSession bgpSession, |
| Collection<BgpRouteEntry> addedBgpRouteEntries, |
| Collection<BgpRouteEntry> deletedBgpRouteEntries) { |
| Collection<RouteUpdate> routeUpdates = new LinkedList<>(); |
| RouteUpdate routeUpdate; |
| |
| if (isShutdown) { |
| return; // Ignore any leftover updates if shutdown |
| } |
| // Process the deleted route entries |
| for (BgpRouteEntry bgpRouteEntry : deletedBgpRouteEntries) { |
| routeUpdate = processDeletedRoute(bgpSession, bgpRouteEntry); |
| if (routeUpdate != null) { |
| routeUpdates.add(routeUpdate); |
| } |
| } |
| |
| // Process the added/updated route entries |
| for (BgpRouteEntry bgpRouteEntry : addedBgpRouteEntries) { |
| routeUpdate = processAddedRoute(bgpSession, bgpRouteEntry); |
| if (routeUpdate != null) { |
| routeUpdates.add(routeUpdate); |
| } |
| } |
| routeListener.update(routeUpdates); |
| } |
| |
| /** |
| * Processes an added/updated route entry. |
| * |
| * @param bgpSession the BGP session the route entry update was |
| * received on |
| * @param bgpRouteEntry the added/updated route entry |
| * @return the result route update that should be forwarded to the |
| * Route Listener, or null if no route update should be forwarded |
| */ |
| private RouteUpdate processAddedRoute(BgpSession bgpSession, |
| BgpRouteEntry bgpRouteEntry) { |
| RouteUpdate routeUpdate; |
| BgpRouteEntry bestBgpRouteEntry = |
| bgpRoutes.get(bgpRouteEntry.prefix()); |
| |
| // |
| // Install the new route entry if it is better than the |
| // current best route. |
| // |
| if ((bestBgpRouteEntry == null) || |
| bgpRouteEntry.isBetterThan(bestBgpRouteEntry)) { |
| bgpRoutes.put(bgpRouteEntry.prefix(), bgpRouteEntry); |
| routeUpdate = |
| new RouteUpdate(RouteUpdate.Type.UPDATE, bgpRouteEntry); |
| return routeUpdate; |
| } |
| |
| // |
| // If the route entry arrived on the same BGP Session as |
| // the current best route, then elect the next best route |
| // and install it. |
| // |
| if (bestBgpRouteEntry.getBgpSession() != |
| bgpRouteEntry.getBgpSession()) { |
| return null; // Nothing to do |
| } |
| |
| // Find the next best route |
| bestBgpRouteEntry = findBestBgpRoute(bgpRouteEntry.prefix()); |
| if (bestBgpRouteEntry == null) { |
| // |
| // TODO: Shouldn't happen. Install the new route as a |
| // pre-caution. |
| // |
| log.debug("BGP next best route for prefix {} is missing. " + |
| "Adding the route that is currently processed.", |
| bgpRouteEntry.prefix()); |
| bestBgpRouteEntry = bgpRouteEntry; |
| } |
| // Install the next best route |
| bgpRoutes.put(bestBgpRouteEntry.prefix(), bestBgpRouteEntry); |
| routeUpdate = new RouteUpdate(RouteUpdate.Type.UPDATE, |
| bestBgpRouteEntry); |
| return routeUpdate; |
| } |
| |
| /** |
| * Processes a deleted route entry. |
| * |
| * @param bgpSession the BGP session the route entry update was |
| * received on |
| * @param bgpRouteEntry the deleted route entry |
| * @return the result route update that should be forwarded to the |
| * Route Listener, or null if no route update should be forwarded |
| */ |
| private RouteUpdate processDeletedRoute(BgpSession bgpSession, |
| BgpRouteEntry bgpRouteEntry) { |
| RouteUpdate routeUpdate; |
| BgpRouteEntry bestBgpRouteEntry = |
| bgpRoutes.get(bgpRouteEntry.prefix()); |
| |
| // |
| // Remove the route entry only if it was the best one. |
| // Install the the next best route if it exists. |
| // |
| // NOTE: We intentionally use "==" instead of method equals(), |
| // because we need to check whether this is same object. |
| // |
| if (bgpRouteEntry != bestBgpRouteEntry) { |
| return null; // Nothing to do |
| } |
| |
| // |
| // Find the next best route |
| // |
| bestBgpRouteEntry = findBestBgpRoute(bgpRouteEntry.prefix()); |
| if (bestBgpRouteEntry != null) { |
| // Install the next best route |
| bgpRoutes.put(bestBgpRouteEntry.prefix(), |
| bestBgpRouteEntry); |
| routeUpdate = new RouteUpdate(RouteUpdate.Type.UPDATE, |
| bestBgpRouteEntry); |
| return routeUpdate; |
| } |
| |
| // |
| // No route found. Remove the route entry |
| // |
| bgpRoutes.remove(bgpRouteEntry.prefix()); |
| routeUpdate = new RouteUpdate(RouteUpdate.Type.DELETE, |
| bgpRouteEntry); |
| return routeUpdate; |
| } |
| |
| /** |
| * Finds the best route entry among all BGP Sessions. |
| * |
| * @param prefix the prefix of the route |
| * @return the best route if found, otherwise null |
| */ |
| private BgpRouteEntry findBestBgpRoute(Ip4Prefix prefix) { |
| BgpRouteEntry bestRoute = null; |
| |
| // Iterate across all BGP Sessions and select the best route |
| for (BgpSession bgpSession : bgpSessions.values()) { |
| BgpRouteEntry route = bgpSession.findBgpRouteEntry(prefix); |
| if (route == null) { |
| continue; |
| } |
| if ((bestRoute == null) || route.isBetterThan(bestRoute)) { |
| bestRoute = route; |
| } |
| } |
| return bestRoute; |
| } |
| } |
| } |