private void sendPacketOut(ConnectPoint outport, Ethernet payload, int sid) {
IPv4 ipPacket = (IPv4) payload.getPayload();
Ip4Address destIpAddress = Ip4Address.valueOf(ipPacket.getDestinationAddress());
if (sid == -1
|| config.getSegmentId(payload.getDestinationMAC()) == sid
|| config.inSameSubnet(outport.deviceId(), destIpAddress)) {
TrafficTreatment treatment =
DefaultTrafficTreatment.builder().setOutput(outport.port()).build();
OutboundPacket packet =
new DefaultOutboundPacket(
outport.deviceId(), treatment, ByteBuffer.wrap(payload.serialize()));
srManager.packetService.emit(packet);
} else {
log.info("Send a MPLS packet as a ICMP response");
TrafficTreatment treatment =
DefaultTrafficTreatment.builder().setOutput(outport.port()).build();
payload.setEtherType(Ethernet.MPLS_UNICAST);
MPLS mplsPkt = new MPLS();
mplsPkt.setLabel(sid);
mplsPkt.setTtl(((IPv4) payload.getPayload()).getTtl());
mplsPkt.setPayload(payload.getPayload());
payload.setPayload(mplsPkt);
OutboundPacket packet =
new DefaultOutboundPacket(
outport.deviceId(), treatment, ByteBuffer.wrap(payload.serialize()));
srManager.packetService.emit(packet);
}
}
/**
* Sends an ICMP reply message.
*
* <p>Note: we assume that packets sending from the edge switches to the hosts have untagged VLAN.
*
* @param icmpRequest the original ICMP request
* @param outport the output port where the ICMP reply should be sent to
*/
private void sendICMPResponse(Ethernet icmpRequest, ConnectPoint outport) {
// Note: We assume that packets arrive at the edge switches have
// untagged VLAN.
Ethernet icmpReplyEth = new Ethernet();
IPv4 icmpRequestIpv4 = (IPv4) icmpRequest.getPayload();
IPv4 icmpReplyIpv4 = new IPv4();
int destAddress = icmpRequestIpv4.getDestinationAddress();
icmpReplyIpv4.setDestinationAddress(icmpRequestIpv4.getSourceAddress());
icmpReplyIpv4.setSourceAddress(destAddress);
icmpReplyIpv4.setTtl((byte) 64);
icmpReplyIpv4.setChecksum((short) 0);
ICMP icmpReply = new ICMP();
icmpReply.setPayload(((ICMP) icmpRequestIpv4.getPayload()).getPayload());
icmpReply.setIcmpType(ICMP.TYPE_ECHO_REPLY);
icmpReply.setIcmpCode(ICMP.SUBTYPE_ECHO_REPLY);
icmpReply.setChecksum((short) 0);
icmpReplyIpv4.setPayload(icmpReply);
icmpReplyEth.setPayload(icmpReplyIpv4);
icmpReplyEth.setEtherType(Ethernet.TYPE_IPV4);
icmpReplyEth.setDestinationMACAddress(icmpRequest.getSourceMACAddress());
icmpReplyEth.setSourceMACAddress(icmpRequest.getDestinationMACAddress());
Ip4Address destIpAddress = Ip4Address.valueOf(icmpReplyIpv4.getDestinationAddress());
Ip4Address destRouterAddress = config.getRouterIpAddressForASubnetHost(destIpAddress);
int sid = config.getSegmentId(destRouterAddress);
if (sid < 0) {
log.warn("Cannot find the Segment ID for {}", destAddress);
return;
}
sendPacketOut(outport, icmpReplyEth, sid);
}