| /* |
| * Copyright 2017-present Open Networking Foundation |
| * |
| * 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.p4tutorial.mytunnel; |
| |
| import com.google.common.collect.Lists; |
| import org.osgi.service.component.annotations.Activate; |
| import org.osgi.service.component.annotations.Component; |
| import org.osgi.service.component.annotations.Deactivate; |
| import org.osgi.service.component.annotations.Reference; |
| import org.osgi.service.component.annotations.ReferenceCardinality; |
| import org.onlab.packet.IpAddress; |
| import org.onosproject.core.ApplicationId; |
| import org.onosproject.core.CoreService; |
| import org.onosproject.net.DeviceId; |
| import org.onosproject.net.Host; |
| import org.onosproject.net.Link; |
| import org.onosproject.net.Path; |
| import org.onosproject.net.PortNumber; |
| import org.onosproject.net.flow.DefaultFlowRule; |
| import org.onosproject.net.flow.DefaultTrafficSelector; |
| import org.onosproject.net.flow.DefaultTrafficTreatment; |
| import org.onosproject.net.flow.FlowRule; |
| import org.onosproject.net.flow.FlowRuleService; |
| import org.onosproject.net.flow.criteria.PiCriterion; |
| import org.onosproject.net.host.HostEvent; |
| import org.onosproject.net.host.HostListener; |
| import org.onosproject.net.host.HostService; |
| import org.onosproject.net.pi.model.PiActionId; |
| import org.onosproject.net.pi.model.PiActionParamId; |
| import org.onosproject.net.pi.model.PiMatchFieldId; |
| import org.onosproject.net.pi.model.PiTableId; |
| import org.onosproject.net.pi.runtime.PiAction; |
| import org.onosproject.net.pi.runtime.PiActionParam; |
| import org.onosproject.net.topology.Topology; |
| import org.onosproject.net.topology.TopologyService; |
| import org.slf4j.Logger; |
| |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Random; |
| import java.util.Set; |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| import static org.slf4j.LoggerFactory.getLogger; |
| |
| /** |
| * MyTunnel application which provides forwarding between each pair of hosts via |
| * MyTunnel protocol as defined in mytunnel.p4. |
| * <p> |
| * The app works by listening for host events. Each time a new host is |
| * discovered, it provisions a tunnel between that host and all the others. |
| */ |
| @Component(immediate = true) |
| public class MyTunnelApp { |
| |
| private static final String APP_NAME = "org.onosproject.p4tutorial.mytunnel"; |
| |
| // Default priority used for flow rules installed by this app. |
| private static final int FLOW_RULE_PRIORITY = 100; |
| |
| private final HostListener hostListener = new InternalHostListener(); |
| private ApplicationId appId; |
| private AtomicInteger nextTunnelId = new AtomicInteger(); |
| |
| private static final Logger log = getLogger(MyTunnelApp.class); |
| |
| //-------------------------------------------------------------------------- |
| // ONOS core services needed by this application. |
| //-------------------------------------------------------------------------- |
| |
| @Reference(cardinality = ReferenceCardinality.MANDATORY) |
| private FlowRuleService flowRuleService; |
| |
| @Reference(cardinality = ReferenceCardinality.MANDATORY) |
| private CoreService coreService; |
| |
| @Reference(cardinality = ReferenceCardinality.MANDATORY) |
| private TopologyService topologyService; |
| |
| @Reference(cardinality = ReferenceCardinality.MANDATORY) |
| private HostService hostService; |
| |
| //-------------------------------------------------------------------------- |
| //-------------------------------------------------------------------------- |
| |
| @Activate |
| public void activate() { |
| // Register app and event listeners. |
| log.info("Starting..."); |
| appId = coreService.registerApplication(APP_NAME); |
| hostService.addListener(hostListener); |
| log.info("STARTED", appId.id()); |
| } |
| |
| @Deactivate |
| public void deactivate() { |
| // Remove listeners and clean-up flow rules. |
| log.info("Stopping..."); |
| hostService.removeListener(hostListener); |
| flowRuleService.removeFlowRulesById(appId); |
| log.info("STOPPED"); |
| } |
| |
| /** |
| * Provisions a tunnel between the given source and destination host with |
| * the given tunnel ID. The tunnel is established using a randomly picked |
| * shortest path based on the given topology snapshot. |
| * |
| * @param tunId tunnel ID |
| * @param srcHost tunnel source host |
| * @param dstHost tunnel destination host |
| * @param topo topology snapshot |
| */ |
| private void provisionTunnel(int tunId, Host srcHost, Host dstHost, Topology topo) { |
| |
| // Get all shortest paths between switches connected to source and |
| // destination hosts. |
| DeviceId srcSwitch = srcHost.location().deviceId(); |
| DeviceId dstSwitch = dstHost.location().deviceId(); |
| |
| List<Link> pathLinks; |
| if (srcSwitch.equals(dstSwitch)) { |
| // Source and dest hosts are connected to the same switch. |
| pathLinks = Collections.emptyList(); |
| } else { |
| // Compute shortest path. |
| Set<Path> allPaths = topologyService.getPaths(topo, srcSwitch, dstSwitch); |
| if (allPaths.size() == 0) { |
| log.warn("No paths between {} and {}", srcHost.id(), dstHost.id()); |
| return; |
| } |
| // If many shortest paths are available, pick a random one. |
| pathLinks = pickRandomPath(allPaths).links(); |
| } |
| |
| // Tunnel ingress rules. |
| for (IpAddress dstIpAddr : dstHost.ipAddresses()) { |
| // In ONOS discovered hosts can have multiple IP addresses. |
| // Insert tunnel ingress rule for each IP address. |
| // Next switches will forward based only on tunnel ID. |
| insertTunnelIngressRule(srcSwitch, dstIpAddr, tunId); |
| } |
| |
| // Insert tunnel transit rules on all switches in the path, excluded the |
| // last one. |
| for (Link link : pathLinks) { |
| DeviceId sw = link.src().deviceId(); |
| PortNumber port = link.src().port(); |
| insertTunnelForwardRule(sw, port, tunId, false); |
| } |
| |
| // Tunnel egress rule. |
| PortNumber egressSwitchPort = dstHost.location().port(); |
| insertTunnelForwardRule(dstSwitch, egressSwitchPort, tunId, true); |
| |
| log.info("** Completed provisioning of tunnel {} (srcHost={} dstHost={})", |
| tunId, srcHost.id(), dstHost.id()); |
| } |
| |
| /** |
| * Generates and insert a flow rule to perform the tunnel INGRESS function |
| * for the given switch, destination IP address and tunnel ID. |
| * |
| * @param switchId switch ID |
| * @param dstIpAddr IP address to forward inside the tunnel |
| * @param tunId tunnel ID |
| */ |
| private void insertTunnelIngressRule(DeviceId switchId, |
| IpAddress dstIpAddr, |
| int tunId) { |
| |
| |
| PiTableId tunnelIngressTableId = PiTableId.of("c_ingress.t_tunnel_ingress"); |
| |
| // Longest prefix match on IPv4 dest address. |
| PiMatchFieldId ipDestMatchFieldId = PiMatchFieldId.of("hdr.ipv4.dst_addr"); |
| PiCriterion match = PiCriterion.builder() |
| .matchLpm(ipDestMatchFieldId, dstIpAddr.toOctets(), 32) |
| .build(); |
| |
| PiActionParam tunIdParam = new PiActionParam(PiActionParamId.of("tun_id"), tunId); |
| |
| PiActionId ingressActionId = PiActionId.of("c_ingress.my_tunnel_ingress"); |
| PiAction action = PiAction.builder() |
| .withId(ingressActionId) |
| .withParameter(tunIdParam) |
| .build(); |
| |
| log.info("Inserting INGRESS rule on switch {}: table={}, match={}, action={}", |
| switchId, tunnelIngressTableId, match, action); |
| |
| insertPiFlowRule(switchId, tunnelIngressTableId, match, action); |
| } |
| |
| /** |
| * Generates and insert a flow rule to perform the tunnel FORWARD/EGRESS |
| * function for the given switch, output port address and tunnel ID. |
| * |
| * @param switchId switch ID |
| * @param outPort output port where to forward tunneled packets |
| * @param tunId tunnel ID |
| * @param isEgress if true, perform tunnel egress action, otherwise forward |
| * packet as is to port |
| */ |
| private void insertTunnelForwardRule(DeviceId switchId, |
| PortNumber outPort, |
| int tunId, |
| boolean isEgress) { |
| |
| PiTableId tunnelForwardTableId = PiTableId.of("c_ingress.t_tunnel_fwd"); |
| |
| // Exact match on tun_id |
| PiMatchFieldId tunIdMatchFieldId = PiMatchFieldId.of("hdr.my_tunnel.tun_id"); |
| PiCriterion match = PiCriterion.builder() |
| .matchExact(tunIdMatchFieldId, tunId) |
| .build(); |
| |
| // Action depend on isEgress parameter. |
| // if true, perform tunnel egress action on the given outPort, otherwise |
| // simply forward packet as is (set_out_port action). |
| PiActionParamId portParamId = PiActionParamId.of("port"); |
| PiActionParam portParam = new PiActionParam(portParamId, (short) outPort.toLong()); |
| |
| final PiAction action; |
| if (isEgress) { |
| // Tunnel egress action. |
| // Remove MyTunnel header and forward to outPort. |
| PiActionId egressActionId = PiActionId.of("c_ingress.my_tunnel_egress"); |
| action = PiAction.builder() |
| .withId(egressActionId) |
| .withParameter(portParam) |
| .build(); |
| } else { |
| // Tunnel transit action. |
| // Forward the packet as is to outPort. |
| /* |
| * TODO EXERCISE: create action object for the transit case. |
| * Look at the t_tunnel_fwd table in the P4 program. Which of the 3 |
| * actions can be used to simply set the output port? Get the full |
| * action name from the P4Info file, and use that when creating the |
| * PiActionId object. When creating the PiAction object, remember to |
| * add all action parameters as defined in the P4 program. |
| * |
| * Hint: the code will be similar to the case when isEgress is true. |
| */ |
| action = null; // Replace null with your solution. |
| } |
| |
| log.info("Inserting {} rule on switch {}: table={}, match={}, action={}", |
| isEgress ? "EGRESS" : "TRANSIT", |
| switchId, tunnelForwardTableId, match, action); |
| |
| insertPiFlowRule(switchId, tunnelForwardTableId, match, action); |
| } |
| |
| /** |
| * Inserts a flow rule in the system that using a PI criterion and action. |
| * |
| * @param switchId switch ID |
| * @param tableId table ID |
| * @param piCriterion PI criterion |
| * @param piAction PI action |
| */ |
| private void insertPiFlowRule(DeviceId switchId, PiTableId tableId, |
| PiCriterion piCriterion, PiAction piAction) { |
| FlowRule rule = DefaultFlowRule.builder() |
| .forDevice(switchId) |
| .forTable(tableId) |
| .fromApp(appId) |
| .withPriority(FLOW_RULE_PRIORITY) |
| .makePermanent() |
| .withSelector(DefaultTrafficSelector.builder() |
| .matchPi(piCriterion).build()) |
| .withTreatment(DefaultTrafficTreatment.builder() |
| .piTableAction(piAction).build()) |
| .build(); |
| flowRuleService.applyFlowRules(rule); |
| } |
| |
| private int getNewTunnelId() { |
| return nextTunnelId.incrementAndGet(); |
| } |
| |
| private Path pickRandomPath(Set<Path> paths) { |
| int item = new Random().nextInt(paths.size()); |
| List<Path> pathList = Lists.newArrayList(paths); |
| return pathList.get(item); |
| } |
| |
| /** |
| * A listener of host events that provisions two tunnels for each pair of |
| * hosts when a new host is discovered. |
| */ |
| private class InternalHostListener implements HostListener { |
| |
| @Override |
| public void event(HostEvent event) { |
| if (event.type() != HostEvent.Type.HOST_ADDED) { |
| // Ignore other host events. |
| return; |
| } |
| synchronized (this) { |
| // Synchronizing here is an overkill, but safer for demo purposes. |
| Host host = event.subject(); |
| Topology topo = topologyService.currentTopology(); |
| for (Host otherHost : hostService.getHosts()) { |
| if (!host.equals(otherHost)) { |
| provisionTunnel(getNewTunnelId(), host, otherHost, topo); |
| provisionTunnel(getNewTunnelId(), otherHost, host, topo); |
| } |
| } |
| } |
| } |
| } |
| } |