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 APR request for the target IP address to all ports except in-port.
*
* @param deviceId Switch device ID
* @param targetAddress target IP address for ARP
* @param inPort in-port
*/
public void sendArpRequest(DeviceId deviceId, IpAddress targetAddress, ConnectPoint inPort) {
byte[] senderMacAddress;
byte[] senderIpAddress;
try {
senderMacAddress = config.getDeviceMac(deviceId).toBytes();
senderIpAddress = config.getRouterIp(deviceId).toOctets();
} catch (DeviceConfigNotFoundException e) {
log.warn(e.getMessage() + " Aborting sendArpRequest.");
return;
}
ARP arpRequest = new ARP();
arpRequest
.setHardwareType(ARP.HW_TYPE_ETHERNET)
.setProtocolType(ARP.PROTO_TYPE_IP)
.setHardwareAddressLength((byte) Ethernet.DATALAYER_ADDRESS_LENGTH)
.setProtocolAddressLength((byte) Ip4Address.BYTE_LENGTH)
.setOpCode(ARP.OP_REQUEST)
.setSenderHardwareAddress(senderMacAddress)
.setTargetHardwareAddress(MacAddress.ZERO.toBytes())
.setSenderProtocolAddress(senderIpAddress)
.setTargetProtocolAddress(targetAddress.toOctets());
Ethernet eth = new Ethernet();
eth.setDestinationMACAddress(MacAddress.BROADCAST.toBytes())
.setSourceMACAddress(senderMacAddress)
.setEtherType(Ethernet.TYPE_ARP)
.setPayload(arpRequest);
removeVlanAndFlood(eth, inPort);
}
private boolean isArpForRouter(DeviceId deviceId, ARP arpMsg) {
Ip4Address targetProtocolAddress = Ip4Address.valueOf(arpMsg.getTargetProtocolAddress());
Set<Ip4Address> gatewayIpAddresses = null;
try {
if (targetProtocolAddress.equals(config.getRouterIp(deviceId))) {
return true;
}
gatewayIpAddresses = config.getPortIPs(deviceId);
} catch (DeviceConfigNotFoundException e) {
log.warn(e.getMessage() + " Aborting check for router IP in processing arp");
}
if (gatewayIpAddresses != null && gatewayIpAddresses.contains(targetProtocolAddress)) {
return true;
}
return false;
}
/**
* Process incoming ICMP packet. If it is an ICMP request to router or known host, then sends an
* ICMP response. If it is an ICMP packet to known host and forward the packet to the host. If it
* is an ICMP packet to unknown host in a subnet, then sends an ARP request to the subnet.
*
* @param pkt inbound packet
*/
public void processPacketIn(InboundPacket pkt) {
Ethernet ethernet = pkt.parsed();
IPv4 ipv4 = (IPv4) ethernet.getPayload();
ConnectPoint connectPoint = pkt.receivedFrom();
DeviceId deviceId = connectPoint.deviceId();
Ip4Address destinationAddress = Ip4Address.valueOf(ipv4.getDestinationAddress());
Set<Ip4Address> gatewayIpAddresses = config.getPortIPs(deviceId);
Ip4Address routerIp;
try {
routerIp = config.getRouterIp(deviceId);
} catch (DeviceConfigNotFoundException e) {
log.warn(e.getMessage() + " Aborting processPacketIn.");
return;
}
IpPrefix routerIpPrefix = IpPrefix.valueOf(routerIp, IpPrefix.MAX_INET_MASK_LENGTH);
Ip4Address routerIpAddress = routerIpPrefix.getIp4Prefix().address();
// ICMP to the router IP or gateway IP
if (((ICMP) ipv4.getPayload()).getIcmpType() == ICMP.TYPE_ECHO_REQUEST
&& (destinationAddress.equals(routerIpAddress)
|| gatewayIpAddresses.contains(destinationAddress))) {
sendICMPResponse(ethernet, connectPoint);
// ICMP for any known host
} else if (!srManager.hostService.getHostsByIp(destinationAddress).isEmpty()) {
// TODO: known host packet should not be coming to controller - resend flows?
srManager.ipHandler.forwardPackets(deviceId, destinationAddress);
// ICMP for an unknown host in the subnet of the router
} else if (config.inSameSubnet(deviceId, destinationAddress)) {
srManager.arpHandler.sendArpRequest(deviceId, destinationAddress, connectPoint);
// ICMP for an unknown host
} else {
log.debug("ICMP request for unknown host {} ", destinationAddress);
// Do nothing
}
}
/**
* 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);
}
private void handleArpRequest(DeviceId deviceId, ConnectPoint inPort, Ethernet payload) {
ARP arpRequest = (ARP) payload.getPayload();
VlanId vlanId = VlanId.vlanId(payload.getVlanID());
HostId targetHostId =
HostId.hostId(MacAddress.valueOf(arpRequest.getTargetHardwareAddress()), vlanId);
// ARP request for router. Send ARP reply.
if (isArpForRouter(deviceId, arpRequest)) {
Ip4Address targetAddress = Ip4Address.valueOf(arpRequest.getTargetProtocolAddress());
sendArpResponse(arpRequest, config.getRouterMacForAGatewayIp(targetAddress), vlanId);
} else {
Host targetHost = srManager.hostService.getHost(targetHostId);
// ARP request for known hosts. Send proxy ARP reply on behalf of the target.
if (targetHost != null) {
removeVlanAndForward(payload, targetHost.location());
// ARP request for unknown host in the subnet. Flood in the subnet.
} else {
removeVlanAndFlood(payload, inPort);
}
}
}