@Override
public void onPacketReceived(PacketReceived potentialArp) {
Arp arp = ArpResolverUtils.getArpFrom(potentialArp);
if (arp != null) {
if (arp.getOperation() != ArpOperation.REPLY.intValue()) {
LOG.trace("Packet is not ARP REPLY packet.");
return;
}
if (LOG.isTraceEnabled()) {
LOG.trace("ARP REPLY received - {}", ArpUtils.getArpToStringFormat(arp));
}
NodeKey nodeKey = potentialArp.getIngress().getValue().firstKeyOf(Node.class, NodeKey.class);
if (nodeKey == null) {
LOG.info("Unknown source node of ARP packet: {}", potentialArp);
return;
}
Ipv4Address gatewayIpAddress = ArpUtils.bytesToIp(arp.getSenderProtocolAddress());
MacAddress gatewayMacAddress = ArpUtils.bytesToMac(arp.getSenderHardwareAddress());
ArpResolverMetadata candidateGatewayIp = gatewayToArpMetadataMap.get(gatewayIpAddress);
if (candidateGatewayIp != null) {
LOG.debug(
"Resolved MAC for Gateway Ip {} is {}",
gatewayIpAddress.getValue(),
gatewayMacAddress.getValue());
candidateGatewayIp.setGatewayMacAddress(gatewayMacAddress);
resetFlowToRemove(gatewayIpAddress, candidateGatewayIp);
}
}
}
private ArpResolverMetadata checkAndGetExternalBridgeDpid(ArpResolverMetadata gatewayMetaData) {
final Long origDpid = gatewayMetaData.getExternalNetworkBridgeDpid();
// If we are not allowing dpid to change, there is nothing further to do here
if (!gatewayMetaData.isRefreshExternalNetworkBridgeDpidIfNeeded()) {
return gatewayMetaData;
}
// If current dpid is null, or if mac is not getting resolved, make an attempt to
// grab a different dpid, so a different (or updated) external bridge gets used
if (origDpid == null || !gatewayMetaData.isGatewayMacAddressResolved()) {
Long newDpid = getAnotherExternalBridgeDpid(origDpid);
gatewayMetaData.setExternalNetworkBridgeDpid(newDpid);
}
return gatewayMetaData;
}
private ArpResolverMetadata resetFlowToRemove(
final Ipv4Address gatewayIp, ArpResolverMetadata gatewayArpMetadata) {
checkNotNull(gatewayIp);
// If gatewayArpMetadata was not provided, look it up
if (gatewayArpMetadata == null) {
gatewayArpMetadata = gatewayToArpMetadataMap.get(gatewayIp);
}
if (gatewayArpMetadata != null && gatewayArpMetadata.getFlowToRemove() != null) {
LOG.debug(
"Flow to route ARP Reply to Controller from {} being removed from node {}",
gatewayIp,
gatewayArpMetadata.getFlowToRemove().getNode());
flowService.removeFlow(gatewayArpMetadata.getFlowToRemove());
gatewayArpMetadata.setFlowToRemove(null);
}
return gatewayArpMetadata;
}
