gomemif: update to libmemif version 4.0

Type: improvement

This patch provides:
1. interrupt mode support,
2. abstract socket support,
3. overriding responder example and divides it to two examples:
	-icmp_responder_cb
	-icmp_responder_poll

Signed-off-by: Daniel Béreš <dberes@cisco.com>
Change-Id: I99c86d053521760c457541fc596ed554f4077608

extras/gomemif/README.rst

@@ -0,0 +1,50 @@
+.. _gomemif_doc:
+
+Gomemif library
+=======================
+
+Memif library implemented in Go. The package contains 3 examples: Bridge and ICMP responder in interrupt and polling mode.
+
+setup and run
+-------------
+To Build all examples
+
+::
+
+   bazel build //...
+
+To Run ICMP responder in interrupt mode:
+
+::
+
+   DBGvpp# create interface memif id 0 master no-zero-copy
+   DBGvpp# set int ip addr memif0/0 192.168.1.2/24
+   DBGvpp# set int state memif0/0 up
+
+   bazel-bin/examples/linux_amd64_stripped/icmp_responder_cb
+   gomemif# start
+
+   DBGvpp# ping 192.168.1.1
+
+To Run ICMP responder in polling mode:
+
+::
+
+   DBGvpp# create interface memif id 0 master no-zero-copy
+   DBGvpp# set int ip addr memif0/0 192.168.1.2/24
+   DBGvpp# set int state memif0/0 up
+
+   bazel-bin/examples/linux_amd64_stripped/icmp_responder_poll
+   gomemif# start
+
+   DBGvpp# ping 192.168.1.1
+
+To Run Bridge:
+
+::
+
+  bazel-bin/examples/linux_amd64_stripped/bridge
+  gomemif# start
+
+
+

extras/gomemif/WORKSPACE

@@ -33,3 +33,8 @@ go_repository(
     importpath = "github.com/pkg/profile",
     commit = "acd64d450fd45fb2afa41f833f3788c8a7797219"
 )
+go_repository(
+    name = "com_github_gopacket",
+    importpath = "github.com/google/gopacket",
+    commit = "3eaba08943250fd212520e5cff00ed808b8fc60a"
+)

extras/gomemif/examples/BUILD.bazel

@@ -1,12 +1,14 @@
 load("@io_bazel_rules_go//go:def.bzl", "go_binary")
 
 go_binary(
-    name = "responder",
-    srcs = ["responder.go"],
+    name = "icmp_responder_poll",
+    srcs = ["icmp_responder_poll.go"],
     visibility = ["//visibility:public",],
     deps = [
     	"//memif:memif",
         "@com_github_profile//:go_default_library",
+        "@com_github_gopacket//layers:go_default_library",
+        "@com_github_gopacket//:go_default_library"
     ],
 )
 
@@ -19,3 +21,16 @@ go_binary(
         "@com_github_profile//:go_default_library",
     ],
 )
+
+go_binary(
+    name = "icmp_responder_cb",
+    srcs = ["icmp_responder_cb.go"],
+    visibility = ["//visibility:public",],
+    deps = [
+    	"//memif:memif",
+        "@com_github_profile//:go_default_library",
+        "@com_github_gopacket//layers:go_default_library",
+        "@com_github_gopacket//:go_default_library"
+    ],
+)
+

extras/gomemif/examples/icmp_responder_poll.go

@@ -21,12 +21,16 @@ import (
 	"bufio"
 	"flag"
 	"fmt"
+	"net"
 	"os"
 	"strings"
 	"sync"
 
-	"github.com/pkg/profile"
 	"memif"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+	"github.com/pkg/profile"
 )
 
 func Disconnected(i *memif.Interface) error {
@@ -78,8 +82,94 @@ func Connected(i *memif.Interface) error {
 				// read packet from shared memory
 				pktLen, err := rxq0.ReadPacket(pkt)
 				if pktLen > 0 {
-					// write packet to shared memory
-					txq0.WritePacket(pkt[:pktLen])
+					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, &ethResp, &ipv4Resp, &icmpResp,
+							gopacket.Payload(icmp.Payload))
+						// write packet to shared memory
+						txq0.WritePacket(buf.Bytes())
+					}
 				} else if err != nil {
 					errChan <- err
 					return

extras/gomemif/memif/control_channel.go

@@ -67,11 +67,22 @@ type Socket struct {
 	interfaceList *list.List
 	ccList        *list.List
 	epfd          int
+	interruptfd   int
 	wakeEvent     syscall.EpollEvent
 	stopPollChan  chan struct{}
 	wg            sync.WaitGroup
 }
 
+type interrupt struct {
+	socket *Socket
+	event  syscall.EpollEvent
+}
+
+type memifInterrupt struct {
+	connection *Socket
+	qid        uint16
+}
+
 // StopPolling stops polling events on the socket
 func (socket *Socket) StopPolling() error {
 	if socket.stopPollChan != nil {
@@ -220,6 +231,15 @@ func (socket *Socket) handleEvent(event *syscall.EpollEvent) error {
 	if socket.listener != nil && socket.listener.event.Fd == event.Fd {
 		return socket.listener.handleEvent(event)
 	}
+	intf := socket.interfaceList.Back().Value.(*Interface)
+	if intf.args.InterruptFunc != nil {
+		if int(event.Fd) == int(intf.args.InterruptFd) {
+			b := make([]byte, 8)
+			syscall.Read(int(event.Fd), b)
+			intf.onInterrupt(intf)
+			return nil
+		}
+	}
 
 	for elt := socket.ccList.Front(); elt != nil; elt = elt.Next() {
 		cc, ok := elt.Value.(*controlChannel)
@@ -233,6 +253,25 @@ func (socket *Socket) handleEvent(event *syscall.EpollEvent) error {
 	return fmt.Errorf(errorFdNotFound)
 }
 
+func (socket *Socket) addInterrupt(fd int) (err error) {
+	l := &interrupt{
+		// we will need this to look up master interface by id
+		socket: socket,
+	}
+
+	l.event = syscall.EpollEvent{
+		Events: syscall.EPOLLIN,
+		Fd:     int32(fd),
+	}
+	err = socket.addEvent(&l.event)
+	if err != nil {
+		return fmt.Errorf("Failed to add event: ", err)
+	}
+
+	return nil
+
+}
+
 // handleEvent handles epoll event for listener
 func (l *listener) handleEvent(event *syscall.EpollEvent) error {
 	// hang up
@@ -725,7 +764,6 @@ func (cc *controlChannel) parseConnect() (err error) {
 	if err != nil {
 		return err
 	}
-
 	cc.isConnected = true
 
 	return nil
@@ -764,7 +802,6 @@ func (cc *controlChannel) parseConnected() (err error) {
 	if err != nil {
 		return err
 	}
-
 	cc.isConnected = true
 
 	return nil

extras/gomemif/memif/interface.go

@@ -60,6 +60,8 @@ type ConnectedFunc func(i *Interface) error
 // DisconnectedFunc is a callback called when an interface is disconnected
 type DisconnectedFunc func(i *Interface) error
 
+type InterruptFunc func(i *Interface) error
+
 // MemoryConfig represents shared memory configuration
 type MemoryConfig struct {
 	NumQueuePairs    uint16 // number of queue pairs
@@ -77,7 +79,9 @@ type Arguments struct {
 	MemoryConfig     MemoryConfig
 	ConnectedFunc    ConnectedFunc    // callback called when interface changes status to connected
 	DisconnectedFunc DisconnectedFunc // callback called when interface changes status to disconnected
-	PrivateData      interface{}      // private data used by client program
+	InterruptFunc    InterruptFunc
+	PrivateData      interface{} // private data used by client program
+	InterruptFd      uint16
 }
 
 // memoryRegion represents a shared memory mapped file
@@ -110,6 +114,7 @@ type Interface struct {
 	regions     []memoryRegion
 	txQueues    []Queue
 	rxQueues    []Queue
+	onInterrupt InterruptFunc
 }
 
 // IsMaster returns true if the interfaces role is master, else returns false
@@ -270,6 +275,10 @@ func RoleToString(isMaster bool) string {
 	return "Slave"
 }
 
+func memifPathIsAbstract(filename string) bool {
+	return (filename[0] == '@')
+}
+
 // RequestConnection is used by slave interface to connect to a socket and
 // create a control channel
 func (i *Interface) RequestConnection() error {
@@ -283,6 +292,9 @@ func (i *Interface) RequestConnection() error {
 	}
 	usa := &syscall.SockaddrUnix{Name: i.socket.filename}
 
+	if memifPathIsAbstract(i.socket.GetFilename()) {
+		usa.Name = "\000" + usa.Name[1:]
+	}
 	// Connect to listener socket
 	err = syscall.Connect(fd, usa)
 	if err != nil {
@@ -315,7 +327,8 @@ func (socket *Socket) NewInterface(args *Arguments) (*Interface, error) {
 
 	// copy interface configuration
 	i := Interface{
-		args: *args,
+		args:        *args,
+		onInterrupt: args.InterruptFunc,
 	}
 	// set default values
 	if i.args.MemoryConfig.NumQueuePairs == 0 {
@@ -434,6 +447,7 @@ func (i *Interface) initializeQueues() (err error) {
 		if err != nil {
 			return err
 		}
+		i.socket.addInterrupt(q.interruptFd)
 		q.putRing()
 		i.txQueues = append(i.txQueues, *q)
 
@@ -452,11 +466,17 @@ func (i *Interface) initializeQueues() (err error) {
 			i:        i,
 		}
 		q.ring.setCookie(cookie)
-		q.ring.setFlags(1)
+		if i.args.InterruptFunc == nil {
+			q.ring.setFlags(1)
+		} else {
+			q.ring.setFlags(0)
+		}
 		q.interruptFd, err = eventFd()
 		if err != nil {
 			return err
 		}
+		i.args.InterruptFd = uint16(q.interruptFd)
+		i.socket.addInterrupt(q.interruptFd)
 		q.putRing()
 		i.rxQueues = append(i.rxQueues, *q)