blob: 778f778182501b307475615a598707882545cfe5 [file] [log] [blame]
/*
* Copyright 2016-present 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.dhcprelay;
import java.nio.ByteBuffer;
import java.util.Dictionary;
import java.util.Objects;
import java.util.Set;
import org.apache.felix.scr.annotations.Activate;
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Deactivate;
import org.apache.felix.scr.annotations.Modified;
import org.apache.felix.scr.annotations.Property;
import org.apache.felix.scr.annotations.Reference;
import org.apache.felix.scr.annotations.ReferenceCardinality;
import org.onlab.packet.ARP;
import org.onlab.packet.DHCP;
import org.onlab.packet.dhcp.DhcpOption;
import org.onlab.packet.Ethernet;
import org.onlab.packet.IPv4;
import org.onlab.packet.Ip4Address;
import org.onlab.packet.IpAddress;
import org.onlab.packet.MacAddress;
import org.onlab.packet.TpPort;
import org.onlab.packet.UDP;
import org.onlab.packet.VlanId;
import org.onlab.util.Tools;
import org.onosproject.core.ApplicationId;
import org.onosproject.core.CoreService;
import org.onosproject.incubator.net.intf.Interface;
import org.onosproject.incubator.net.intf.InterfaceService;
import org.onosproject.net.ConnectPoint;
import org.onosproject.net.Host;
import org.onosproject.net.HostId;
import org.onosproject.net.config.ConfigFactory;
import org.onosproject.net.config.NetworkConfigEvent;
import org.onosproject.net.config.NetworkConfigListener;
import org.onosproject.net.config.NetworkConfigRegistry;
import org.onosproject.net.flow.DefaultTrafficSelector;
import org.onosproject.net.flow.DefaultTrafficTreatment;
import org.onosproject.net.flow.TrafficSelector;
import org.onosproject.net.flow.TrafficTreatment;
import org.onosproject.net.host.HostEvent;
import org.onosproject.net.host.HostListener;
import org.onosproject.net.host.HostService;
import org.onosproject.net.host.InterfaceIpAddress;
import org.onosproject.net.packet.DefaultOutboundPacket;
import org.onosproject.net.packet.OutboundPacket;
import org.onosproject.net.packet.PacketContext;
import org.onosproject.net.packet.PacketPriority;
import org.onosproject.net.packet.PacketProcessor;
import org.onosproject.net.packet.PacketService;
import org.osgi.service.component.ComponentContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.collect.ImmutableSet;
import static org.onosproject.net.config.basics.SubjectFactories.APP_SUBJECT_FACTORY;
import static org.onlab.packet.DHCP.DHCPOptionCode.OptionCode_MessageType;
import static org.onlab.packet.MacAddress.valueOf;
/**
* DHCP Relay Agent Application Component.
*/
@Component(immediate = true)
public class DhcpRelay {
public static final String DHCP_RELAY_APP = "org.onosproject.dhcp-relay";
private final Logger log = LoggerFactory.getLogger(getClass());
private final InternalConfigListener cfgListener = new InternalConfigListener();
private static MacAddress myMAC = valueOf("4f:4f:4f:4f:4f:4f");
private final Set<ConfigFactory> factories = ImmutableSet.of(
new ConfigFactory<ApplicationId, DhcpRelayConfig>(APP_SUBJECT_FACTORY,
DhcpRelayConfig.class,
"dhcprelay") {
@Override
public DhcpRelayConfig createConfig() {
return new DhcpRelayConfig();
}
}
);
@Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
protected NetworkConfigRegistry cfgService;
@Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
protected CoreService coreService;
@Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
protected PacketService packetService;
@Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
protected HostService hostService;
@Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
protected InterfaceService interfaceService;
@Property(name = "arpEnabled", boolValue = true,
label = "Enable Address resolution protocol")
protected boolean arpEnabled = true;
private DhcpRelayPacketProcessor dhcpRelayPacketProcessor = new DhcpRelayPacketProcessor();
private InternalHostListener hostListener = new InternalHostListener();
private Ip4Address dhcpServerIp = null;
// dhcp server may be connected directly to the SDN network or
// via an external gateway. When connected directly, the dhcpConnectPoint, dhcpConnectMac,
// and dhcpConnectVlan refer to the server. When connected via the gateway, they refer
// to the gateway.
private ConnectPoint dhcpServerConnectPoint = null;
private MacAddress dhcpConnectMac = null;
private VlanId dhcpConnectVlan = null;
private Ip4Address dhcpGatewayIp = null;
private ApplicationId appId;
@Activate
protected void activate(ComponentContext context) {
//start the dhcp relay agent
appId = coreService.registerApplication(DHCP_RELAY_APP);
cfgService.addListener(cfgListener);
factories.forEach(cfgService::registerConfigFactory);
//update the dhcp server configuration.
updateConfig();
//add the packet services.
packetService.addProcessor(dhcpRelayPacketProcessor, PacketProcessor.director(0));
hostService.addListener(hostListener);
requestDhcpPackets();
modified(context);
log.info("DHCP-RELAY Started");
}
@Deactivate
protected void deactivate() {
cfgService.removeListener(cfgListener);
factories.forEach(cfgService::unregisterConfigFactory);
packetService.removeProcessor(dhcpRelayPacketProcessor);
hostService.removeListener(hostListener);
cancelDhcpPackets();
cancelArpPackets();
if (dhcpGatewayIp != null) {
hostService.stopMonitoringIp(dhcpGatewayIp);
} else {
hostService.stopMonitoringIp(dhcpServerIp);
}
log.info("DHCP-RELAY Stopped");
}
@Modified
protected void modified(ComponentContext context) {
Dictionary<?, ?> properties = context.getProperties();
Boolean flag;
flag = Tools.isPropertyEnabled(properties, "arpEnabled");
if (flag != null) {
arpEnabled = flag;
log.info("Address resolution protocol is {}",
arpEnabled ? "enabled" : "disabled");
}
if (arpEnabled) {
requestArpPackets();
} else {
cancelArpPackets();
}
}
/**
* Checks if this app has been configured.
*
* @return true if all information we need have been initialized
*/
private boolean configured() {
return dhcpServerConnectPoint != null && dhcpServerIp != null;
}
private void updateConfig() {
DhcpRelayConfig cfg = cfgService.getConfig(appId, DhcpRelayConfig.class);
if (cfg == null) {
log.warn("Dhcp Server info not available");
return;
}
dhcpServerConnectPoint = cfg.getDhcpServerConnectPoint();
Ip4Address oldDhcpServerIp = dhcpServerIp;
Ip4Address oldDhcpGatewayIp = dhcpGatewayIp;
dhcpServerIp = cfg.getDhcpServerIp();
dhcpGatewayIp = cfg.getDhcpGatewayIp();
dhcpConnectMac = null; // reset for updated config
dhcpConnectVlan = null; // reset for updated config
log.info("DHCP server connect point: " + dhcpServerConnectPoint);
log.info("DHCP server ipaddress " + dhcpServerIp);
IpAddress ipToProbe = dhcpGatewayIp != null ? dhcpGatewayIp : dhcpServerIp;
String hostToProbe = dhcpGatewayIp != null ? "gateway" : "DHCP server";
Set<Host> hosts = hostService.getHostsByIp(ipToProbe);
if (hosts.isEmpty()) {
log.info("Probing to resolve {} IP {}", hostToProbe, ipToProbe);
if (oldDhcpGatewayIp != null) {
hostService.stopMonitoringIp(oldDhcpGatewayIp);
}
if (oldDhcpServerIp != null) {
hostService.stopMonitoringIp(oldDhcpServerIp);
}
hostService.startMonitoringIp(ipToProbe);
} else {
// Probe target is known; There should be only 1 host with this ip
hostUpdated(hosts.iterator().next());
}
}
private void hostRemoved(Host host) {
if (host.ipAddresses().contains(dhcpServerIp)) {
log.warn("DHCP server {} removed", dhcpServerIp);
dhcpConnectMac = null;
dhcpConnectVlan = null;
}
if (dhcpGatewayIp != null && host.ipAddresses().contains(dhcpGatewayIp)) {
log.warn("DHCP gateway {} removed", dhcpGatewayIp);
dhcpConnectMac = null;
dhcpConnectVlan = null;
}
}
private void hostUpdated(Host host) {
if (dhcpGatewayIp != null) {
if (host.ipAddresses().contains(dhcpGatewayIp)) {
dhcpConnectMac = host.mac();
dhcpConnectVlan = host.vlan();
log.info("DHCP gateway {} resolved to Mac/Vlan:{}/{}", dhcpGatewayIp,
dhcpConnectMac, dhcpConnectVlan);
}
return;
}
if (host.ipAddresses().contains(dhcpServerIp)) {
dhcpConnectMac = host.mac();
dhcpConnectVlan = host.vlan();
log.info("DHCP server {} resolved to Mac/Vlan:{}/{}", dhcpServerIp,
dhcpConnectMac, dhcpConnectVlan);
}
}
/**
* Request DHCP packet in via PacketService.
*/
private void requestDhcpPackets() {
TrafficSelector.Builder selectorServer = DefaultTrafficSelector.builder()
.matchEthType(Ethernet.TYPE_IPV4)
.matchIPProtocol(IPv4.PROTOCOL_UDP)
.matchUdpSrc(TpPort.tpPort(UDP.DHCP_SERVER_PORT));
packetService.requestPackets(selectorServer.build(), PacketPriority.CONTROL, appId);
TrafficSelector.Builder selectorClient = DefaultTrafficSelector.builder()
.matchEthType(Ethernet.TYPE_IPV4)
.matchIPProtocol(IPv4.PROTOCOL_UDP)
.matchUdpSrc(TpPort.tpPort(UDP.DHCP_CLIENT_PORT));
packetService.requestPackets(selectorClient.build(), PacketPriority.CONTROL, appId);
}
/**
* Cancel requested DHCP packets in via packet service.
*/
private void cancelDhcpPackets() {
TrafficSelector.Builder selectorServer = DefaultTrafficSelector.builder()
.matchEthType(Ethernet.TYPE_IPV4)
.matchIPProtocol(IPv4.PROTOCOL_UDP)
.matchUdpSrc(TpPort.tpPort(UDP.DHCP_SERVER_PORT));
packetService.cancelPackets(selectorServer.build(), PacketPriority.CONTROL, appId);
TrafficSelector.Builder selectorClient = DefaultTrafficSelector.builder()
.matchEthType(Ethernet.TYPE_IPV4)
.matchIPProtocol(IPv4.PROTOCOL_UDP)
.matchUdpSrc(TpPort.tpPort(UDP.DHCP_CLIENT_PORT));
packetService.cancelPackets(selectorClient.build(), PacketPriority.CONTROL, appId);
}
/**
* Request ARP packet in via PacketService.
*/
private void requestArpPackets() {
TrafficSelector.Builder selectorArpServer = DefaultTrafficSelector.builder()
.matchEthType(Ethernet.TYPE_ARP);
packetService.requestPackets(selectorArpServer.build(), PacketPriority.CONTROL, appId);
}
/**
* Cancel requested ARP packets in via packet service.
*/
private void cancelArpPackets() {
TrafficSelector.Builder selectorArpServer = DefaultTrafficSelector.builder()
.matchEthType(Ethernet.TYPE_ARP);
packetService.cancelPackets(selectorArpServer.build(), PacketPriority.CONTROL, appId);
}
private class DhcpRelayPacketProcessor implements PacketProcessor {
@Override
public void process(PacketContext context) {
if (!configured()) {
log.warn("Missing DHCP relay server config. Abort packet processing");
return;
}
// process the packet and get the payload
Ethernet packet = context.inPacket().parsed();
if (packet == null) {
return;
}
if (packet.getEtherType() == Ethernet.TYPE_IPV4) {
IPv4 ipv4Packet = (IPv4) packet.getPayload();
if (ipv4Packet.getProtocol() == IPv4.PROTOCOL_UDP) {
UDP udpPacket = (UDP) ipv4Packet.getPayload();
DHCP dhcpPayload = (DHCP) udpPacket.getPayload();
if (udpPacket.getSourcePort() == UDP.DHCP_CLIENT_PORT ||
udpPacket.getSourcePort() == UDP.DHCP_SERVER_PORT) {
//This packet is dhcp.
processDhcpPacket(context, dhcpPayload);
}
}
} else if (packet.getEtherType() == Ethernet.TYPE_ARP && arpEnabled) {
ARP arpPacket = (ARP) packet.getPayload();
Set<Interface> serverInterfaces = interfaceService.
getInterfacesByPort(context.inPacket().receivedFrom());
//ignore the packets if dhcp server interface is not configured on onos.
if (serverInterfaces.isEmpty()) {
log.warn("server virtual interface not configured");
return;
}
if ((arpPacket.getOpCode() == ARP.OP_REQUEST) &&
checkArpRequestFrmDhcpServ(serverInterfaces, arpPacket)) {
processArpPacket(context, packet);
}
}
}
//method to check the arp request is from dhcp server for default-gateway.
private boolean checkArpRequestFrmDhcpServ(Set<Interface> serverInterfaces, ARP arpPacket) {
if (Objects.equals(serverInterfaces.iterator().next().ipAddressesList().get(0).
ipAddress().getIp4Address(),
Ip4Address.valueOf(arpPacket.getTargetProtocolAddress()))) {
return true;
}
return false;
}
//forward the packet to ConnectPoint where the DHCP server is attached.
private void forwardPacket(Ethernet packet) {
//send Packetout to dhcp server connectpoint.
if (dhcpServerConnectPoint != null) {
TrafficTreatment t = DefaultTrafficTreatment.builder()
.setOutput(dhcpServerConnectPoint.port()).build();
OutboundPacket o = new DefaultOutboundPacket(
dhcpServerConnectPoint.deviceId(), t, ByteBuffer.wrap(packet.serialize()));
if (log.isTraceEnabled()) {
log.trace("Relaying packet to dhcp server {}", packet);
}
packetService.emit(o);
}
}
/**
* Processes the ARP Payload and initiates a reply to the client.
*
* @param context context of the incoming message
* @param packet the ethernet payload
*/
private void processArpPacket(PacketContext context, Ethernet packet) {
ARP arpPacket = (ARP) packet.getPayload();
ARP arpReply = (ARP) arpPacket.clone();
arpReply.setOpCode(ARP.OP_REPLY);
arpReply.setTargetProtocolAddress(arpPacket.getSenderProtocolAddress());
arpReply.setTargetHardwareAddress(arpPacket.getSenderHardwareAddress());
arpReply.setSenderProtocolAddress(arpPacket.getTargetProtocolAddress());
arpReply.setSenderHardwareAddress(myMAC.toBytes());
// Ethernet Frame.
Ethernet ethReply = new Ethernet();
ethReply.setSourceMACAddress(myMAC);
ethReply.setDestinationMACAddress(packet.getSourceMAC());
ethReply.setEtherType(Ethernet.TYPE_ARP);
ethReply.setVlanID(packet.getVlanID());
ethReply.setPayload(arpReply);
forwardPacket(ethReply);
}
//process the dhcp packet before sending to server
private void processDhcpPacket(PacketContext context, DHCP dhcpPayload) {
ConnectPoint inPort = context.inPacket().receivedFrom();
Set<Interface> clientServerInterfaces = interfaceService.getInterfacesByPort(inPort);
//ignore the packets if dhcp client interface is not configured on onos.
if (clientServerInterfaces.isEmpty()) {
log.warn("Virtual interface is not configured on {}", inPort);
return;
}
if (dhcpPayload == null) {
return;
}
Ethernet packet = context.inPacket().parsed();
DHCP.MsgType incomingPacketType = null;
for (DhcpOption option : dhcpPayload.getOptions()) {
if (option.getCode() == OptionCode_MessageType.getValue()) {
byte[] data = option.getData();
incomingPacketType = DHCP.MsgType.getType(data[0]);
}
}
switch (incomingPacketType) {
case DHCPDISCOVER:
// add the gatewayip as virtual interface ip for server to understand
// the lease to be assigned and forward the packet to dhcp server.
Ethernet ethernetPacketDiscover =
processDhcpPacketFromClient(context, packet, clientServerInterfaces);
if (ethernetPacketDiscover != null) {
forwardPacket(ethernetPacketDiscover);
}
break;
case DHCPOFFER:
//reply to dhcp client.
Ethernet ethernetPacketOffer = processDhcpPacketFromServer(packet);
if (ethernetPacketOffer != null) {
sendReply(ethernetPacketOffer, dhcpPayload);
}
break;
case DHCPREQUEST:
// add the gatewayip as virtual interface ip for server to understand
// the lease to be assigned and forward the packet to dhcp server.
Ethernet ethernetPacketRequest =
processDhcpPacketFromClient(context, packet, clientServerInterfaces);
if (ethernetPacketRequest != null) {
forwardPacket(ethernetPacketRequest);
}
break;
case DHCPACK:
//reply to dhcp client.
Ethernet ethernetPacketAck = processDhcpPacketFromServer(packet);
if (ethernetPacketAck != null) {
sendReply(ethernetPacketAck, dhcpPayload);
}
break;
default:
break;
}
}
//build the DHCP discover/request packet with gatewayip(unicast packet)
private Ethernet processDhcpPacketFromClient(PacketContext context,
Ethernet ethernetPacket, Set<Interface> clientInterfaces) {
Ip4Address relayAgentIp = getRelayAgentIPv4Address(clientInterfaces);
MacAddress relayAgentMac = clientInterfaces.iterator().next().mac();
if (relayAgentIp == null || relayAgentMac == null) {
log.warn("Missing DHCP relay agent interface Ipv4 addr config for "
+ "packet from client on port: {}. Aborting packet processing",
clientInterfaces.iterator().next().connectPoint());
return null;
}
if (dhcpConnectMac == null) {
log.warn("DHCP {} not yet resolved .. Aborting DHCP "
+ "packet processing from client on port: {}",
(dhcpGatewayIp == null) ? "server IP " + dhcpServerIp
: "gateway IP " + dhcpGatewayIp,
clientInterfaces.iterator().next().connectPoint());
return null;
}
// get dhcp header.
Ethernet etherReply = (Ethernet) ethernetPacket.clone();
etherReply.setSourceMACAddress(relayAgentMac);
etherReply.setDestinationMACAddress(dhcpConnectMac);
etherReply.setVlanID(dhcpConnectVlan.toShort());
IPv4 ipv4Packet = (IPv4) etherReply.getPayload();
ipv4Packet.setSourceAddress(relayAgentIp.toInt());
ipv4Packet.setDestinationAddress(dhcpServerIp.toInt());
UDP udpPacket = (UDP) ipv4Packet.getPayload();
DHCP dhcpPacket = (DHCP) udpPacket.getPayload();
dhcpPacket.setGatewayIPAddress(relayAgentIp.toInt());
udpPacket.setPayload(dhcpPacket);
ipv4Packet.setPayload(udpPacket);
etherReply.setPayload(ipv4Packet);
return etherReply;
}
// Returns the first v4 interface ip out of a set of interfaces or null.
// Checks all interfaces, and ignores v6 interface ips
private Ip4Address getRelayAgentIPv4Address(Set<Interface> intfs) {
for (Interface intf : intfs) {
for (InterfaceIpAddress ip : intf.ipAddressesList()) {
Ip4Address relayAgentIp = ip.ipAddress().getIp4Address();
if (relayAgentIp != null) {
return relayAgentIp;
}
}
}
return null;
}
//build the DHCP offer/ack with proper client port.
private Ethernet processDhcpPacketFromServer(Ethernet ethernetPacket) {
// get dhcp header.
Ethernet etherReply = (Ethernet) ethernetPacket.clone();
IPv4 ipv4Packet = (IPv4) etherReply.getPayload();
UDP udpPacket = (UDP) ipv4Packet.getPayload();
DHCP dhcpPayload = (DHCP) udpPacket.getPayload();
// determine the vlanId of the client host - note that this vlan id
// could be different from the vlan in the packet from the server
MacAddress dstMac = valueOf(dhcpPayload.getClientHardwareAddress());
Set<Host> hosts = hostService.getHostsByMac(dstMac);
if (hosts == null || hosts.isEmpty()) {
log.warn("Cannot determine host for DHCP client: {}. Aborting "
+ "relay for dhcp packet from server {}",
dhcpPayload.getClientHardwareAddress(), ethernetPacket);
return null;
} else if (hosts.size() > 1) {
// XXX redo to send reply to all hosts found
log.warn("Multiple hosts found for mac:{}. Picking one "
+ "host out of {}", dstMac, hosts);
}
Host host = hosts.iterator().next();
etherReply.setDestinationMACAddress(dstMac);
etherReply.setVlanID(host.vlan().toShort());
// we leave the srcMac from the original packet
// figure out the relay agent IP corresponding to the original request
Ip4Address relayAgentIP = getRelayAgentIPv4Address(
interfaceService.getInterfacesByPort(host.location()));
if (relayAgentIP == null) {
log.warn("Cannot determine relay agent interface Ipv4 addr for host {}. "
+ "Aborting relay for dhcp packet from server {}",
host, ethernetPacket);
return null;
}
// SRC_IP: relay agent IP
// DST_IP: offered IP
ipv4Packet.setSourceAddress(relayAgentIP.toInt());
ipv4Packet.setDestinationAddress(dhcpPayload.getYourIPAddress());
udpPacket.setDestinationPort(UDP.DHCP_CLIENT_PORT);
udpPacket.setPayload(dhcpPayload);
ipv4Packet.setPayload(udpPacket);
etherReply.setPayload(ipv4Packet);
return etherReply;
}
//send the response to the requester host.
private void sendReply(Ethernet ethPacket, DHCP dhcpPayload) {
MacAddress descMac = valueOf(dhcpPayload.getClientHardwareAddress());
Host host = hostService.getHost(HostId.hostId(descMac,
VlanId.vlanId(ethPacket.getVlanID())));
// Send packet out to requester if the host information is available
if (host != null) {
TrafficTreatment t = DefaultTrafficTreatment.builder()
.setOutput(host.location().port()).build();
OutboundPacket o = new DefaultOutboundPacket(
host.location().deviceId(), t, ByteBuffer.wrap(ethPacket.serialize()));
if (log.isTraceEnabled()) {
log.trace("Relaying packet to dhcp client {}", ethPacket);
}
packetService.emit(o);
}
}
}
/**
* Listener for network config events.
*/
private class InternalConfigListener implements NetworkConfigListener {
@Override
public void event(NetworkConfigEvent event) {
if ((event.type() == NetworkConfigEvent.Type.CONFIG_ADDED ||
event.type() == NetworkConfigEvent.Type.CONFIG_UPDATED) &&
event.configClass().equals(DhcpRelayConfig.class)) {
updateConfig();
log.info("Reconfigured");
}
}
}
/**
* Internal listener for host events.
*/
private class InternalHostListener implements HostListener {
@Override
public void event(HostEvent event) {
switch (event.type()) {
case HOST_ADDED:
case HOST_UPDATED:
hostUpdated(event.subject());
break;
case HOST_REMOVED:
hostRemoved(event.subject());
break;
case HOST_MOVED:
// XXX todo -- moving dhcp server
break;
default:
break;
}
}
}
}