diff options
Diffstat (limited to 'extras/gomemif/examples/icmp_responder_cb.go')
-rw-r--r-- | extras/gomemif/examples/icmp_responder_cb.go | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/extras/gomemif/examples/icmp_responder_cb.go b/extras/gomemif/examples/icmp_responder_cb.go new file mode 100644 index 00000000000..8d8adcfc892 --- /dev/null +++ b/extras/gomemif/examples/icmp_responder_cb.go @@ -0,0 +1,326 @@ +/* + *------------------------------------------------------------------ + * Copyright (c) 2020 Cisco and/or its affiliates. + * 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 main + +import ( + "bufio" + "flag" + "fmt" + "net" + "os" + "strings" + "sync" + + "memif" + + "github.com/google/gopacket" + "github.com/google/gopacket/layers" + "github.com/pkg/profile" +) + +func Disconnected(i *memif.Interface) error { + fmt.Println("Disconnected: ", i.GetName()) + + data, ok := i.GetPrivateData().(*interfaceData) + if !ok { + return fmt.Errorf("Invalid private data") + } + close(data.quitChan) // stop polling + close(data.errChan) + data.wg.Wait() // wait until polling stops, then continue disconnect + + return nil +} + +func Responder(i *memif.Interface) error { + data, ok := i.GetPrivateData().(*interfaceData) + if !ok { + return fmt.Errorf("Invalid private data") + } + data.errChan = make(chan error, 1) + data.quitChan = make(chan struct{}, 1) + data.wg.Add(1) + + // allocate packet buffer + pkt := make([]byte, 2048) + // get rx queue + rxq0, err := i.GetRxQueue(0) + if err != nil { + return err + } + // get tx queue + txq0, err := i.GetTxQueue(0) + if err != nil { + return err + } + for { + + // read packet from shared memory + pktLen, err := rxq0.ReadPacket(pkt) + _ = err + if pktLen > 0 { + fmt.Printf("pktLen: %d\n", pktLen) + gopkt := gopacket.NewPacket(pkt[:pktLen], layers.LayerTypeEthernet, gopacket.NoCopy) + etherLayer := gopkt.Layer(layers.LayerTypeEthernet) + if etherLayer.(*layers.Ethernet).EthernetType == layers.EthernetTypeARP { + rEth := layers.Ethernet{ + SrcMAC: net.HardwareAddr{0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa}, + DstMAC: net.HardwareAddr{0xff, 0xff, 0xff, 0xff, 0xff, 0xff}, + + EthernetType: layers.EthernetTypeARP, + } + rArp := layers.ARP{ + AddrType: layers.LinkTypeEthernet, + Protocol: layers.EthernetTypeIPv4, + HwAddressSize: 6, + ProtAddressSize: 4, + Operation: layers.ARPReply, + SourceHwAddress: []byte(net.HardwareAddr{0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa}), + SourceProtAddress: []byte("\xc0\xa8\x01\x01"), + DstHwAddress: []byte(net.HardwareAddr{0x02, 0xfe, 0x08, 0x88, 0x45, 0x7f}), + DstProtAddress: []byte("\xc0\xa8\x01\x02"), + } + buf := gopacket.NewSerializeBuffer() + opts := gopacket.SerializeOptions{ + FixLengths: true, + ComputeChecksums: true, + } + gopacket.SerializeLayers(buf, opts, &rEth, &rArp) + // write packet to shared memory + txq0.WritePacket(buf.Bytes()) + } + + if etherLayer.(*layers.Ethernet).EthernetType == layers.EthernetTypeIPv4 { + ipLayer := gopkt.Layer(layers.LayerTypeIPv4) + if ipLayer == nil { + fmt.Println("Missing IPv4 layer.") + + } + ipv4, _ := ipLayer.(*layers.IPv4) + if ipv4.Protocol != layers.IPProtocolICMPv4 { + fmt.Println("Not ICMPv4 protocol.") + } + icmpLayer := gopkt.Layer(layers.LayerTypeICMPv4) + if icmpLayer == nil { + fmt.Println("Missing ICMPv4 layer.") + } + icmp, _ := icmpLayer.(*layers.ICMPv4) + if icmp.TypeCode.Type() != layers.ICMPv4TypeEchoRequest { + fmt.Println("Not ICMPv4 echo request.") + } + fmt.Println("Received an ICMPv4 echo request.") + + // Build packet layers. + ethResp := layers.Ethernet{ + DstMAC: net.HardwareAddr{0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa}, + //DstMAC: net.HardwareAddr{0x02, 0xfe, 0xa8, 0x77, 0xaf, 0x20}, + SrcMAC: []byte(net.HardwareAddr{0x02, 0xfe, 0x08, 0x88, 0x45, 0x7f}), + + EthernetType: layers.EthernetTypeIPv4, + } + ipv4Resp := layers.IPv4{ + Version: 4, + IHL: 5, + TOS: 0, + Id: 0, + Flags: 0, + FragOffset: 0, + TTL: 255, + Protocol: layers.IPProtocolICMPv4, + SrcIP: []byte("\xc0\xa8\x01\x01"), + DstIP: []byte("\xc0\xa8\x01\x02"), + } + icmpResp := layers.ICMPv4{ + TypeCode: layers.CreateICMPv4TypeCode(layers.ICMPv4TypeEchoReply, 0), + Id: icmp.Id, + Seq: icmp.Seq, + } + + // Set up buffer and options for serialization. + buf := gopacket.NewSerializeBuffer() + opts := gopacket.SerializeOptions{ + FixLengths: true, + ComputeChecksums: true, + } + gopacket.SerializeLayers(buf, opts, ðResp, &ipv4Resp, &icmpResp, + gopacket.Payload(icmp.Payload)) + // write packet to shared memory + txq0.WritePacket(buf.Bytes()) + } + + } + return nil + + } + +} +func Connected(i *memif.Interface) error { + data, ok := i.GetPrivateData().(*interfaceData) + if !ok { + return fmt.Errorf("Invalid private data") + } + _ = data + + // allocate packet buffer + pkt := make([]byte, 2048) + // get rx queue + rxq0, err := i.GetRxQueue(0) + _ = err + + // read packet from shared memory + pktLen, err := rxq0.ReadPacket(pkt) + _, _ = err, pktLen + + return nil +} + +type interfaceData struct { + errChan chan error + quitChan chan struct{} + wg sync.WaitGroup +} + +func interractiveHelp() { + fmt.Println("help - print this help") + fmt.Println("start - start connecting loop") + fmt.Println("show - print interface details") + fmt.Println("exit - exit the application") +} + +func main() { + cpuprof := flag.String("cpuprof", "", "cpu profiling output file") + memprof := flag.String("memprof", "", "mem profiling output file") + role := flag.String("role", "slave", "interface role") + name := flag.String("name", "gomemif", "interface name") + socketName := flag.String("socket", "/run/vpp/memif.sock", "control socket filename") + + flag.Parse() + + if *cpuprof != "" { + defer profile.Start(profile.CPUProfile, profile.ProfilePath(*cpuprof)).Stop() + } + if *memprof != "" { + defer profile.Start(profile.MemProfile, profile.ProfilePath(*memprof)).Stop() + } + + memifErrChan := make(chan error) + exitChan := make(chan struct{}) + + var isMaster bool + switch *role { + case "slave": + isMaster = false + case "master": + isMaster = true + default: + fmt.Println("Invalid role") + return + } + + fmt.Println("GoMemif: Responder") + fmt.Println("-----------------------") + + socket, err := memif.NewSocket("gomemif_example", *socketName) + if err != nil { + fmt.Println("Failed to create socket: ", err) + return + } + + data := interfaceData{} + args := &memif.Arguments{ + IsMaster: isMaster, + ConnectedFunc: Connected, + DisconnectedFunc: Disconnected, + PrivateData: &data, + Name: *name, + InterruptFunc: Responder, + } + + i, err := socket.NewInterface(args) + if err != nil { + fmt.Println("Failed to create interface on socket %s: %s", socket.GetFilename(), err) + goto exit + } + + // slave attempts to connect to control socket + // to handle control communication call socket.StartPolling() + if !i.IsMaster() { + fmt.Println(args.Name, ": Connecting to control socket...") + for !i.IsConnecting() { + err = i.RequestConnection() + if err != nil { + /* TODO: check for ECONNREFUSED errno + * if error is ECONNREFUSED it may simply mean that master + * interface is not up yet, use i.RequestConnection() + */ + fmt.Println("Failed to connect: ", err) + goto exit + } + } + } + + go func(exitChan chan<- struct{}) { + reader := bufio.NewReader(os.Stdin) + for { + fmt.Print("gomemif# ") + text, _ := reader.ReadString('\n') + // convert CRLF to LF + text = strings.Replace(text, "\n", "", -1) + switch text { + case "help": + interractiveHelp() + case "start": + // start polling for events on this socket + socket.StartPolling(memifErrChan) + case "show": + fmt.Println("remote: ", i.GetRemoteName()) + fmt.Println("peer: ", i.GetPeerName()) + case "exit": + err = socket.StopPolling() + if err != nil { + fmt.Println("Failed to stop polling: ", err) + } + close(exitChan) + return + default: + fmt.Println("Unknown input") + } + } + }(exitChan) + + for { + select { + case <-exitChan: + goto exit + case err, ok := <-memifErrChan: + if ok { + fmt.Println(err) + } + case err, ok := <-data.errChan: + if ok { + fmt.Println(err) + } + default: + continue + } + } + +exit: + socket.Delete() + close(memifErrChan) +} |