Port the BGP implementation of SDN-IP.

@@ -126,6 +126,8 @@ public class Router implements RouteListener {
         bgpIntentsSynchronizerExecutor = Executors.newSingleThreadExecutor(
                 new ThreadFactoryBuilder()
                 .setNameFormat("bgp-intents-synchronizer-%d").build());
+
+        this.hostService.addListener(new InternalHostListener());
     }
 
     /**

@@ -10,6 +10,7 @@ import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.onlab.onos.net.host.HostService;
 import org.onlab.onos.net.intent.IntentService;
 import org.onlab.onos.sdnip.RouteUpdate.Type;
+import org.onlab.onos.sdnip.bgp.BgpSessionManager;
 import org.onlab.onos.sdnip.config.SdnIpConfigReader;
 import org.onlab.packet.IpAddress;
 import org.onlab.packet.IpPrefix;
@@ -32,6 +33,7 @@ public class SdnIp {
     private SdnIpConfigReader config;
     private PeerConnectivity peerConnectivity;
     private Router router;
+    private BgpSessionManager bgpSessionManager;
 
     @Activate
     protected void activate() {
@@ -48,6 +50,9 @@ public class SdnIp {
         router = new Router(intentService, hostService, config, interfaceService);
         router.start();
 
+        bgpSessionManager = new BgpSessionManager(router);
+        bgpSessionManager.startUp(2000); // TODO
+
         // TODO need to disable link discovery on external ports
 
         router.update(new RouteUpdate(Type.UPDATE, new RouteEntry(

+package org.onlab.onos.sdnip.bgp;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.buffer.ChannelBuffers;
+import org.jboss.netty.channel.Channel;
+import org.jboss.netty.channel.ChannelHandlerContext;
+import org.jboss.netty.handler.codec.frame.FrameDecoder;
+import org.onlab.onos.sdnip.bgp.BgpConstants.Notifications.MessageHeaderError;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Class for handling the decoding of the BGP messages.
+ */
+class BgpFrameDecoder extends FrameDecoder {
+    private static final Logger log =
+        LoggerFactory.getLogger(BgpFrameDecoder.class);
+
+    private final BgpSession bgpSession;
+
+    /**
+     * Constructor for a given BGP Session.
+     *
+     * @param bgpSession the BGP session state to use.
+     */
+    BgpFrameDecoder(BgpSession bgpSession) {
+        this.bgpSession = bgpSession;
+    }
+
+    @Override
+    protected Object decode(ChannelHandlerContext ctx,
+                            Channel channel,
+                            ChannelBuffer buf) throws Exception {
+        //
+        // NOTE: If we close the channel during the decoding, we might still
+        // see some incoming messages while the channel closing is completed.
+        //
+        if (bgpSession.isClosed()) {
+            return null;
+        }
+
+        log.trace("BGP Peer: decode(): remoteAddr = {} localAddr = {} " +
+                  "messageSize = {}",
+                  ctx.getChannel().getRemoteAddress(),
+                  ctx.getChannel().getLocalAddress(),
+                  buf.readableBytes());
+
+        // Test for minimum length of the BGP message
+        if (buf.readableBytes() < BgpConstants.BGP_HEADER_LENGTH) {
+            // No enough data received
+            return null;
+        }
+
+        //
+        // Mark the current buffer position in case we haven't received
+        // the whole message.
+        //
+        buf.markReaderIndex();
+
+        //
+        // Read and check the BGP message Marker field: it must be all ones
+        // (See RFC 4271, Section 4.1)
+        //
+        byte[] marker = new byte[BgpConstants.BGP_HEADER_MARKER_LENGTH];
+        buf.readBytes(marker);
+        for (int i = 0; i < marker.length; i++) {
+            if (marker[i] != (byte) 0xff) {
+                log.debug("BGP RX Error: invalid marker {} at position {}",
+                          marker[i], i);
+                //
+                // ERROR: Connection Not Synchronized
+                //
+                // Send NOTIFICATION and close the connection
+                int errorCode = MessageHeaderError.ERROR_CODE;
+                int errorSubcode =
+                    MessageHeaderError.CONNECTION_NOT_SYNCHRONIZED;
+                ChannelBuffer txMessage =
+                    bgpSession.prepareBgpNotification(errorCode, errorSubcode,
+                                                      null);
+                ctx.getChannel().write(txMessage);
+                bgpSession.closeChannel(ctx);
+                return null;
+            }
+        }
+
+        //
+        // Read and check the BGP message Length field
+        //
+        int length = buf.readUnsignedShort();
+        if ((length < BgpConstants.BGP_HEADER_LENGTH) ||
+            (length > BgpConstants.BGP_MESSAGE_MAX_LENGTH)) {
+            log.debug("BGP RX Error: invalid Length field {}. " +
+                      "Must be between {} and {}",
+                      length,
+                      BgpConstants.BGP_HEADER_LENGTH,
+                      BgpConstants.BGP_MESSAGE_MAX_LENGTH);
+            //
+            // ERROR: Bad Message Length
+            //
+            // Send NOTIFICATION and close the connection
+            ChannelBuffer txMessage =
+                bgpSession.prepareBgpNotificationBadMessageLength(length);
+            ctx.getChannel().write(txMessage);
+            bgpSession.closeChannel(ctx);
+            return null;
+        }
+
+        //
+        // Test whether the rest of the message is received:
+        // So far we have read the Marker (16 octets) and the
+        // Length (2 octets) fields.
+        //
+        int remainingMessageLen =
+            length - BgpConstants.BGP_HEADER_MARKER_LENGTH - 2;
+        if (buf.readableBytes() < remainingMessageLen) {
+            // No enough data received
+            buf.resetReaderIndex();
+            return null;
+        }
+
+        //
+        // Read the BGP message Type field, and process based on that type
+        //
+        int type = buf.readUnsignedByte();
+        remainingMessageLen--;      // Adjust after reading the type
+        ChannelBuffer message = buf.readBytes(remainingMessageLen);
+
+        //
+        // Process the remaining of the message based on the message type
+        //
+        switch (type) {
+        case BgpConstants.BGP_TYPE_OPEN:
+            bgpSession.processBgpOpen(ctx, message);
+            break;
+        case BgpConstants.BGP_TYPE_UPDATE:
+            bgpSession.processBgpUpdate(ctx, message);
+            break;
+        case BgpConstants.BGP_TYPE_NOTIFICATION:
+            bgpSession.processBgpNotification(ctx, message);
+            break;
+        case BgpConstants.BGP_TYPE_KEEPALIVE:
+            bgpSession.processBgpKeepalive(ctx, message);
+            break;
+        default:
+            //
+            // ERROR: Bad Message Type
+            //
+            // Send NOTIFICATION and close the connection
+            int errorCode = MessageHeaderError.ERROR_CODE;
+            int errorSubcode = MessageHeaderError.BAD_MESSAGE_TYPE;
+            ChannelBuffer data = ChannelBuffers.buffer(1);
+            data.writeByte(type);
+            ChannelBuffer txMessage =
+                bgpSession.prepareBgpNotification(errorCode, errorSubcode,
+                                                  data);
+            ctx.getChannel().write(txMessage);
+            bgpSession.closeChannel(ctx);
+            return null;
+        }
+        return null;
+    }
+}

+/**
+ * Implementation of the BGP protocol.
+ */
+package org.onlab.onos.sdnip.bgp;
\ No newline at end of file

@@ -2,13 +2,15 @@ package org.onlab.packet;
 
 import java.util.Arrays;
 
+
+
 /**
  * A class representing an IPv4 address.
  * <p/>
  * TODO this class is a clone of IpPrefix and still needs to be modified to
  * look more like an IpAddress.
  */
-public final class IpAddress {
+public final class IpAddress implements Comparable<IpAddress> {
 
     // TODO a comparator for netmasks? E.g. for sorting by prefix match order.
 
@@ -289,6 +291,13 @@ public final class IpAddress {
     }
 
     @Override
+    public int compareTo(IpAddress o) {
+        Long lv = ((long) this.toRealInt()) & 0xffffffffL;
+        Long rv = ((long) o.toRealInt()) & 0xffffffffL;
+        return lv.compareTo(rv);
+    }
+
+    @Override
     public int hashCode() {
         final int prime = 31;
         int result = 1;