Chore: adjust gVisor stack

hub/executor/executor.go

@@ -330,7 +330,9 @@ func updateIPTables(cfg *config.Config) {
 	log.Infoln("[IPTABLES] Setting iptables completed")
 }
 
-func Cleanup() {
+func Shutdown() {
 	P.Cleanup()
 	tproxy.CleanupTProxyIPTables()
+
+	log.Warnln("Clash shutting down")
 }

hub/hub.go

@@ -48,7 +48,3 @@ func Parse(options ...Option) error {
 	executor.ApplyConfig(cfg, true)
 	return nil
 }
-
-func Cleanup() {
-	executor.Cleanup()
-}

listener/tun/device/device.go

@@ -29,4 +29,7 @@ type Device interface {
 
 	// UseIOBased work for other ip stack
 	UseIOBased() error
+
+	// Wait waits for the device to close.
+	Wait()
 }

listener/tun/device/iobased/endpoint.go

@@ -103,7 +103,7 @@ func (e *Endpoint) dispatchLoop(cancel context.CancelFunc) {
 		case header.IPv6Version:
 			e.InjectInbound(header.IPv6ProtocolNumber, pkt)
 		}
-		pkt.DecRef() /* release */
+		pkt.DecRef()
 	}
 }
 

listener/tun/device/tun/tun_wireguard.go

@@ -106,6 +106,9 @@ func (t *TUN) Write(packet []byte) (int, error) {
 }
 
 func (t *TUN) Close() error {
+	if t.Endpoint != nil {
+		t.Endpoint.Close()
+	}
 	return t.nt.Close()
 }
 

listener/tun/ipstack/gvisor/adapter/handler.go

@@ -3,6 +3,12 @@ package adapter
 // Handler is a TCP/UDP connection handler that implements
 // HandleTCPConn and HandleUDPConn methods.
 type Handler interface {
-	HandleTCPConn(TCPConn)
+	HandleTCP(TCPConn)
-	HandleUDPConn(UDPConn)
+	HandleUDP(UDPConn)
 }
+
+// TCPHandleFunc handles incoming TCP connection.
+type TCPHandleFunc func(TCPConn)
+
+// UDPHandleFunc handles incoming UDP connection.
+type UDPHandleFunc func(UDPConn)

listener/tun/ipstack/gvisor/handler.go

@@ -24,7 +24,7 @@ type GVHandler struct {
 	UDPIn chan<- *inbound.PacketAdapter
 }
 
-func (gh *GVHandler) HandleTCPConn(tunConn adapter.TCPConn) {
+func (gh *GVHandler) HandleTCP(tunConn adapter.TCPConn) {
 	id := tunConn.ID()
 
 	rAddr := &net.UDPAddr{
@@ -77,7 +77,7 @@ func (gh *GVHandler) HandleTCPConn(tunConn adapter.TCPConn) {
 	gh.TCPIn <- inbound.NewSocket(socks5.ParseAddrToSocksAddr(rAddr), tunConn, C.TUN)
 }
 
-func (gh *GVHandler) HandleUDPConn(tunConn adapter.UDPConn) {
+func (gh *GVHandler) HandleUDP(tunConn adapter.UDPConn) {
 	id := tunConn.ID()
 
 	rAddr := &net.UDPAddr{

listener/tun/ipstack/gvisor/nic.go

@@ -3,14 +3,13 @@ package gvisor
 import (
 	"fmt"
 
+	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/option"
+
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 )
 
 const (
-	// defaultNICID is the ID of default NIC used by DefaultStack.
-	defaultNICID tcpip.NICID = 0x01
-
 	// nicPromiscuousModeEnabled is the value used by stack to enable
 	// or disable NIC's promiscuous mode.
 	nicPromiscuousModeEnabled = true
@@ -21,9 +20,9 @@ const (
 )
 
 // withCreatingNIC creates NIC for stack.
-func withCreatingNIC(ep stack.LinkEndpoint) Option {
+func withCreatingNIC(nicID tcpip.NICID, ep stack.LinkEndpoint) option.Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
-		if err := s.CreateNICWithOptions(s.nicID, ep,
+		if err := s.CreateNICWithOptions(nicID, ep,
 			stack.NICOptions{
 				Disabled: false,
 				// If no queueing discipline was specified
@@ -37,21 +36,21 @@ func withCreatingNIC(ep stack.LinkEndpoint) Option {
 	}
 }
 
-// withPromiscuousMode sets promiscuous mode in the given NIC.
+// withPromiscuousMode sets promiscuous mode in the given NICs.
-func withPromiscuousMode(v bool) Option {
+func withPromiscuousMode(nicID tcpip.NICID, v bool) option.Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
-		if err := s.SetPromiscuousMode(s.nicID, v); err != nil {
+		if err := s.SetPromiscuousMode(nicID, v); err != nil {
 			return fmt.Errorf("set promiscuous mode: %s", err)
 		}
 		return nil
 	}
 }
 
-// withSpoofing sets address spoofing in the given NIC, allowing
+// withSpoofing sets address spoofing in the given NICs, allowing
 // endpoints to bind to any address in the NIC.
-func withSpoofing(v bool) Option {
+func withSpoofing(nicID tcpip.NICID, v bool) option.Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
-		if err := s.SetSpoofing(s.nicID, v); err != nil {
+		if err := s.SetSpoofing(nicID, v); err != nil {
 			return fmt.Errorf("set spoofing: %s", err)
 		}
 		return nil

listener/tun/ipstack/gvisor/option/option.go

@@ -1,4 +1,4 @@
-package gvisor
+package option
 
 import (
 	"fmt"
@@ -7,6 +7,7 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
 	"gvisor.dev/gvisor/pkg/tcpip/network/ipv6"
+	"gvisor.dev/gvisor/pkg/tcpip/stack"
 	"gvisor.dev/gvisor/pkg/tcpip/transport/tcp"
 )
 
@@ -56,11 +57,11 @@ const (
 	tcpDefaultBufferSize = 212 << 10 // 212 KiB
 )
 
-type Option func(*gvStack) error
+type Option func(*stack.Stack) error
 
 // WithDefault sets all default values for stack.
 func WithDefault() Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		opts := []Option{
 			WithDefaultTTL(defaultTimeToLive),
 			WithForwarding(ipForwardingEnabled),
@@ -110,7 +111,7 @@ func WithDefault() Option {
 
 // WithDefaultTTL sets the default TTL used by stack.
 func WithDefaultTTL(ttl uint8) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		opt := tcpip.DefaultTTLOption(ttl)
 		if err := s.SetNetworkProtocolOption(ipv4.ProtocolNumber, &opt); err != nil {
 			return fmt.Errorf("set ipv4 default TTL: %s", err)
@@ -124,7 +125,7 @@ func WithDefaultTTL(ttl uint8) Option {
 
 // WithForwarding sets packet forwarding between NICs for IPv4 & IPv6.
 func WithForwarding(v bool) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		if err := s.SetForwardingDefaultAndAllNICs(ipv4.ProtocolNumber, v); err != nil {
 			return fmt.Errorf("set ipv4 forwarding: %s", err)
 		}
@@ -138,7 +139,7 @@ func WithForwarding(v bool) Option {
 // WithICMPBurst sets the number of ICMP messages that can be sent
 // in a single burst.
 func WithICMPBurst(burst int) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		s.SetICMPBurst(burst)
 		return nil
 	}
@@ -147,7 +148,7 @@ func WithICMPBurst(burst int) Option {
 // WithICMPLimit sets the maximum number of ICMP messages permitted
 // by rate limiter.
 func WithICMPLimit(limit rate.Limit) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		s.SetICMPLimit(limit)
 		return nil
 	}
@@ -155,7 +156,7 @@ func WithICMPLimit(limit rate.Limit) Option {
 
 // WithTCPBufferSizeRange sets the receive and send buffer size range for TCP.
 func WithTCPBufferSizeRange(a, b, c int) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		rcvOpt := tcpip.TCPReceiveBufferSizeRangeOption{Min: a, Default: b, Max: c}
 		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &rcvOpt); err != nil {
 			return fmt.Errorf("set TCP receive buffer size range: %s", err)
@@ -170,7 +171,7 @@ func WithTCPBufferSizeRange(a, b, c int) Option {
 
 // WithTCPCongestionControl sets the current congestion control algorithm.
 func WithTCPCongestionControl(cc string) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		opt := tcpip.CongestionControlOption(cc)
 		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &opt); err != nil {
 			return fmt.Errorf("set TCP congestion control algorithm: %s", err)
@@ -181,7 +182,7 @@ func WithTCPCongestionControl(cc string) Option {
 
 // WithTCPDelay enables or disables Nagle's algorithm in TCP.
 func WithTCPDelay(v bool) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		opt := tcpip.TCPDelayEnabled(v)
 		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &opt); err != nil {
 			return fmt.Errorf("set TCP delay: %s", err)
@@ -192,7 +193,7 @@ func WithTCPDelay(v bool) Option {
 
 // WithTCPModerateReceiveBuffer sets receive buffer moderation for TCP.
 func WithTCPModerateReceiveBuffer(v bool) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		opt := tcpip.TCPModerateReceiveBufferOption(v)
 		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &opt); err != nil {
 			return fmt.Errorf("set TCP moderate receive buffer: %s", err)
@@ -203,7 +204,7 @@ func WithTCPModerateReceiveBuffer(v bool) Option {
 
 // WithTCPSACKEnabled sets the SACK option for TCP.
 func WithTCPSACKEnabled(v bool) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		opt := tcpip.TCPSACKEnabled(v)
 		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &opt); err != nil {
 			return fmt.Errorf("set TCP SACK: %s", err)
@@ -214,7 +215,7 @@ func WithTCPSACKEnabled(v bool) Option {
 
 // WithTCPRecovery sets the recovery option for TCP.
 func WithTCPRecovery(v tcpip.TCPRecovery) Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
 		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &v); err != nil {
 			return fmt.Errorf("set TCP Recovery: %s", err)
 		}

listener/tun/ipstack/gvisor/route.go

@@ -1,22 +1,23 @@
 package gvisor
 
 import (
+	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/option"
+
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
+	"gvisor.dev/gvisor/pkg/tcpip/stack"
 )
 
-func withICMPHandler() Option {
+func withRouteTable(nicID tcpip.NICID) option.Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
-		// Add default route table for IPv4 and IPv6.
-		// This will handle all incoming ICMP packets.
 		s.SetRouteTable([]tcpip.Route{
 			{
 				Destination: header.IPv4EmptySubnet,
-				NIC:         s.nicID,
+				NIC:         nicID,
 			},
 			{
 				Destination: header.IPv6EmptySubnet,
-				NIC:         s.nicID,
+				NIC:         nicID,
 			},
 		})
 		return nil

listener/tun/ipstack/gvisor/stack.go

@@ -5,6 +5,7 @@ import (
 	"github.com/Dreamacro/clash/listener/tun/device"
 	"github.com/Dreamacro/clash/listener/tun/ipstack"
 	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/adapter"
+	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/option"
 
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
@@ -18,23 +19,23 @@ import (
 type gvStack struct {
 	*stack.Stack
 	device device.Device
-
-	handler adapter.Handler
-	nicID   tcpip.NICID
 }
 
 func (s *gvStack) Close() error {
+	var err error
+	if s.device != nil {
+		err = s.device.Close()
+		s.device.Wait()
+	}
 	if s.Stack != nil {
 		s.Stack.Close()
+		s.Stack.Wait()
 	}
-	if s.device != nil {
+	return err
-		_ = s.device.Close()
-	}
-	return nil
 }
 
 // New allocates a new *gvStack with given options.
-func New(device device.Device, handler adapter.Handler, opts ...Option) (ipstack.Stack, error) {
+func New(device device.Device, handler adapter.Handler, opts ...option.Option) (ipstack.Stack, error) {
 	s := &gvStack{
 		Stack: stack.New(stack.Options{
 			NetworkProtocols: []stack.NetworkProtocolFactory{
@@ -49,19 +50,15 @@ func New(device device.Device, handler adapter.Handler, opts ...Option) (ipstack
 			},
 		}),
 
-		device:  device,
+		device: device,
-		handler: handler,
-		nicID:   defaultNICID,
 	}
 
-	opts = append(opts,
+	// Generate unique NIC id.
-		// Important: We must initiate transport protocol handlers
+	nicID := tcpip.NICID(s.Stack.UniqueID())
-		// before creating NIC, otherwise NIC would dispatch packets
-		// to stack and cause race condition.
-		withICMPHandler(), withTCPHandler(), withUDPHandler(),
 
-		// Create stack NIC and then bind link endpoint.
+	opts = append(opts,
-		withCreatingNIC(device.(stack.LinkEndpoint)),
+		// Create stack NIC and then bind link endpoint to it.
+		withCreatingNIC(nicID, device),
 
 		// In the past we did s.AddAddressRange to assign 0.0.0.0/0
 		// onto the interface. We need that to be able to terminate
@@ -70,27 +67,34 @@ func New(device device.Device, handler adapter.Handler, opts ...Option) (ipstack
 		// Promiscuous mode. https://github.com/google/gvisor/issues/3876
 		//
 		// Ref: https://github.com/cloudflare/slirpnetstack/blob/master/stack.go
-		withPromiscuousMode(nicPromiscuousModeEnabled),
+		withPromiscuousMode(nicID, nicPromiscuousModeEnabled),
 
-		// Enable spoofing if a stack may send packets from unowned addresses.
+		// Enable spoofing if a stack may send packets from unowned
-		// This change required changes to some netgophers since previously,
+		// addresses. This change required changes to some netgophers
-		// promiscuous mode was enough to let the netstack respond to all
+		// since previously, promiscuous mode was enough to let the
-		// incoming packets regardless of the packet's destination address. Now
+		// netstack respond to all incoming packets regardless of the
-		// that a stack.Route is not held for each incoming packet, finding a route
+		// packet's destination address. Now that a stack.Route is not
-		// may fail with local addresses we don't own but accepted packets for
+		// held for each incoming packet, finding a route may fail with
-		// while in promiscuous mode. Since we also want to be able to send from
+		// local addresses we don't own but accepted packets for while
-		// any address (in response the received promiscuous mode packets), we need
+		// in promiscuous mode. Since we also want to be able to send
-		// to enable spoofing.
+		// from any address (in response the received promiscuous mode
+		// packets), we need to enable spoofing.
 		//
 		// Ref: https://github.com/google/gvisor/commit/8c0701462a84ff77e602f1626aec49479c308127
-		withSpoofing(nicSpoofingEnabled),
+		withSpoofing(nicID, nicSpoofingEnabled),
+
+		// Add default route table for IPv4 and IPv6. This will handle
+		// all incoming ICMP packets.
+		withRouteTable(nicID),
+
+		// Initiate transport protocol (TCP/UDP) with given handler.
+		withTCPHandler(handler.HandleTCP), withUDPHandler(handler.HandleUDP),
 	)
 
 	for _, opt := range opts {
-		if err := opt(s); err != nil {
+		if err := opt(s.Stack); err != nil {
 			return nil, err
 		}
 	}
-
 	return s, nil
 }

listener/tun/ipstack/gvisor/tcp.go

@@ -4,6 +4,9 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/adapter"
+	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/option"
+
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/adapters/gonet"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
@@ -37,9 +40,9 @@ const (
 	tcpKeepaliveInterval = 30 * time.Second
 )
 
-func withTCPHandler() Option {
+func withTCPHandler(handle adapter.TCPHandleFunc) option.Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
-		tcpForwarder := tcp.NewForwarder(s.Stack, defaultWndSize, maxConnAttempts, func(r *tcp.ForwarderRequest) {
+		tcpForwarder := tcp.NewForwarder(s, defaultWndSize, maxConnAttempts, func(r *tcp.ForwarderRequest) {
 			var wq waiter.Queue
 			ep, err := r.CreateEndpoint(&wq)
 			if err != nil {
@@ -55,7 +58,7 @@ func withTCPHandler() Option {
 				TCPConn: gonet.NewTCPConn(&wq, ep),
 				id:      r.ID(),
 			}
-			s.handler.HandleTCPConn(conn)
+			handle(conn)
 		})
 		s.SetTransportProtocolHandler(tcp.ProtocolNumber, tcpForwarder.HandlePacket)
 		return nil

listener/tun/ipstack/gvisor/udp.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/Dreamacro/clash/common/pool"
 	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/adapter"
+	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/option"
 
 	"gvisor.dev/gvisor/pkg/tcpip/adapters/gonet"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
@@ -12,9 +13,9 @@ import (
 	"gvisor.dev/gvisor/pkg/waiter"
 )
 
-func withUDPHandler() Option {
+func withUDPHandler(handle adapter.UDPHandleFunc) option.Option {
-	return func(s *gvStack) error {
+	return func(s *stack.Stack) error {
-		udpForwarder := udp.NewForwarder(s.Stack, func(r *udp.ForwarderRequest) {
+		udpForwarder := udp.NewForwarder(s, func(r *udp.ForwarderRequest) {
 			var wq waiter.Queue
 			ep, err := r.CreateEndpoint(&wq)
 			if err != nil {
@@ -23,10 +24,10 @@ func withUDPHandler() Option {
 			}
 
 			conn := &udpConn{
-				UDPConn: gonet.NewUDPConn(s.Stack, &wq, ep),
+				UDPConn: gonet.NewUDPConn(s, &wq, ep),
 				id:      r.ID(),
 			}
-			s.handler.HandleUDPConn(conn)
+			handle(conn)
 		})
 		s.SetTransportProtocolHandler(udp.ProtocolNumber, udpForwarder.HandlePacket)
 		return nil

listener/tun/ipstack/system/stack.go

@@ -36,8 +36,6 @@ func (s sysStack) Close() error {
 	return nil
 }
 
-var ipv4LoopBack = netip.MustParsePrefix("127.0.0.0/8")
-
 func New(device device.Device, dnsHijack []netip.AddrPort, tunAddress netip.Prefix, tcpIn chan<- C.ConnContext, udpIn chan<- *inbound.PacketAdapter) (ipstack.Stack, error) {
 	var (
 		gateway = tunAddress.Masked().Addr().Next()
@@ -71,12 +69,6 @@ func New(device device.Device, dnsHijack []netip.AddrPort, tunAddress netip.Pref
 			rAddrIp, _ := netip.AddrFromSlice(rAddr.IP)
 			rAddrPort := netip.AddrPortFrom(rAddrIp, uint16(rAddr.Port))
 
-			if ipv4LoopBack.Contains(rAddrIp) {
-				conn.Close()
-
-				continue
-			}
-
 			if D.ShouldHijackDns(dnsAddr, rAddrPort) {
 				go func() {
 					log.Debugln("[TUN] hijack dns tcp: %s", rAddrPort.String())
@@ -149,12 +141,6 @@ func New(device device.Device, dnsHijack []netip.AddrPort, tunAddress netip.Pref
 			rAddrIp, _ := netip.AddrFromSlice(rAddr.IP)
 			rAddrPort := netip.AddrPortFrom(rAddrIp, uint16(rAddr.Port))
 
-			if ipv4LoopBack.Contains(rAddrIp) {
-				pool.Put(buf)
-
-				continue
-			}
-
 			if D.ShouldHijackDns(dnsAddr, rAddrPort) {
 				go func() {
 					defer pool.Put(buf)

listener/tun/tun_adapter.go

@@ -18,6 +18,7 @@ import (
 	"github.com/Dreamacro/clash/listener/tun/ipstack"
 	"github.com/Dreamacro/clash/listener/tun/ipstack/commons"
 	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor"
+	"github.com/Dreamacro/clash/listener/tun/ipstack/gvisor/option"
 	"github.com/Dreamacro/clash/listener/tun/ipstack/system"
 	"github.com/Dreamacro/clash/log"
 )
@@ -67,7 +68,7 @@ func New(tunConf *config.Tun, tunAddressPrefix string, tcpIn chan<- C.ConnContex
 				DNSAdds: tunConf.DNSHijack,
 				TCPIn:   tcpIn, UDPIn: udpIn,
 			},
-			gvisor.WithDefault(),
+			option.WithDefault(),
 		)
 
 		if err != nil {

main.go

@@ -100,13 +100,9 @@ func main() {
 		log.Fatalln("Parse config error: %s", err.Error())
 	}
 
+	defer executor.Shutdown()
+
 	sigCh := make(chan os.Signal, 1)
 	signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM)
 	<-sigCh
-
-	// cleanup
-	log.Warnln("Clash cleanup")
-	hub.Cleanup()
-
-	log.Warnln("Clash shutting down")
 }