Improve darwin tun performance

tun_darwin_gvisor.go

@@ -3,132 +3,23 @@
 package tun
 
 import (
-	"github.com/sagernet/gvisor/pkg/buffer"
-	"github.com/sagernet/gvisor/pkg/tcpip"
-	"github.com/sagernet/gvisor/pkg/tcpip/header"
+	"github.com/sagernet/gvisor/pkg/tcpip/link/qdisc/fifo"
 	"github.com/sagernet/gvisor/pkg/tcpip/stack"
-	"github.com/sagernet/sing/common/bufio"
+	"github.com/sagernet/sing-tun/internal/fdbased_darwin"
 )
 
 var _ GVisorTun = (*NativeTun)(nil)
 
-func (t *NativeTun) NewEndpoint() (stack.LinkEndpoint, error) {
-	return &DarwinEndpoint{tun: t}, nil
-}
-
-var _ stack.LinkEndpoint = (*DarwinEndpoint)(nil)
-
-type DarwinEndpoint struct {
-	tun        *NativeTun
-	dispatcher stack.NetworkDispatcher
-}
-
-func (e *DarwinEndpoint) MTU() uint32 {
-	return e.tun.options.MTU
-}
-
-func (e *DarwinEndpoint) SetMTU(mtu uint32) {
-}
-
-func (e *DarwinEndpoint) MaxHeaderLength() uint16 {
-	return 0
-}
-
-func (e *DarwinEndpoint) LinkAddress() tcpip.LinkAddress {
-	return ""
-}
-
-func (e *DarwinEndpoint) SetLinkAddress(addr tcpip.LinkAddress) {
-}
-
-func (e *DarwinEndpoint) Capabilities() stack.LinkEndpointCapabilities {
-	return stack.CapabilityRXChecksumOffload
-}
-
-func (e *DarwinEndpoint) Attach(dispatcher stack.NetworkDispatcher) {
-	if dispatcher == nil && e.dispatcher != nil {
-		e.dispatcher = nil
-		return
-	}
-	if dispatcher != nil && e.dispatcher == nil {
-		e.dispatcher = dispatcher
-		go e.dispatchLoop()
+func (t *NativeTun) NewEndpoint() (stack.LinkEndpoint, stack.NICOptions, error) {
+	ep, err := fdbased.New(&fdbased.Options{
+		FDs:               []int{t.tunFd},
+		MTU:               t.options.MTU,
+		RXChecksumOffload: true,
+	})
+	if err != nil {
+		return nil, stack.NICOptions{}, err
 	}
-}
-
-func (e *DarwinEndpoint) dispatchLoop() {
-	packetBuffer := make([]byte, e.tun.options.MTU+PacketOffset)
-	for {
-		n, err := e.tun.tunFile.Read(packetBuffer)
-		if err != nil {
-			break
-		}
-		packet := packetBuffer[PacketOffset:n]
-		var networkProtocol tcpip.NetworkProtocolNumber
-		switch header.IPVersion(packet) {
-		case header.IPv4Version:
-			networkProtocol = header.IPv4ProtocolNumber
-			if header.IPv4(packet).DestinationAddress().As4() == e.tun.inet4Address {
-				e.tun.tunFile.Write(packetBuffer[:n])
-				continue
-			}
-		case header.IPv6Version:
-			networkProtocol = header.IPv6ProtocolNumber
-			if header.IPv6(packet).DestinationAddress().As16() == e.tun.inet6Address {
-				e.tun.tunFile.Write(packetBuffer[:n])
-				continue
-			}
-		default:
-			e.tun.tunFile.Write(packetBuffer[:n])
-			continue
-		}
-		pkt := stack.NewPacketBuffer(stack.PacketBufferOptions{
-			Payload:           buffer.MakeWithData(packetBuffer[4:n]),
-			IsForwardedPacket: true,
-		})
-		pkt.NetworkProtocolNumber = networkProtocol
-		dispatcher := e.dispatcher
-		if dispatcher == nil {
-			pkt.DecRef()
-			return
-		}
-		dispatcher.DeliverNetworkPacket(networkProtocol, pkt)
-		pkt.DecRef()
-	}
-}
-
-func (e *DarwinEndpoint) IsAttached() bool {
-	return e.dispatcher != nil
-}
-
-func (e *DarwinEndpoint) Wait() {
-}
-
-func (e *DarwinEndpoint) ARPHardwareType() header.ARPHardwareType {
-	return header.ARPHardwareNone
-}
-
-func (e *DarwinEndpoint) AddHeader(buffer *stack.PacketBuffer) {
-}
-
-func (e *DarwinEndpoint) ParseHeader(ptr *stack.PacketBuffer) bool {
-	return true
-}
-
-func (e *DarwinEndpoint) WritePackets(packetBufferList stack.PacketBufferList) (int, tcpip.Error) {
-	var n int
-	for _, packet := range packetBufferList.AsSlice() {
-		_, err := bufio.WriteVectorised(e.tun, packet.AsSlices())
-		if err != nil {
-			return n, &tcpip.ErrAborted{}
-		}
-		n++
-	}
-	return n, nil
-}
-
-func (e *DarwinEndpoint) Close() {
-}
-
-func (e *DarwinEndpoint) SetOnCloseAction(f func()) {
+	return ep, stack.NICOptions{
+		QDisc: fifo.New(ep, 1, 1000),
+	}, nil
 }