Transport: Refactor to be based on Finalmask's dialer & listener (#6754)

https://github.com/XTLS/Xray-core/pull/6327#issuecomment-5645958010
https://github.com/XTLS/Xray-core/pull/6754#issuecomment-5720818254
https://github.com/XTLS/Xray-core/pull/6754#issuecomment-5751585906

infra/conf/transport_finalmask.go

@@ -14,7 +14,6 @@ import (
 	googleuuid "github.com/google/uuid"
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/net"
-	"github.com/xtls/xray-core/transport/internet"
 	"github.com/xtls/xray-core/transport/internet/finalmask/fragment"
 	"github.com/xtls/xray-core/transport/internet/finalmask/header/custom"
 	"github.com/xtls/xray-core/transport/internet/finalmask/mkcp/aes128gcm"
@@ -909,22 +908,13 @@ func (c *Realm) Build() (proto.Message, error) {
 }
 
 type UDPHop struct {
-	Sockopt     *SocketConfig `json:"sockopt"`
-	Mode        string        `json:"mode"`
-	Interval    Int32Range    `json:"interval"`
-	RemotePorts PortList      `json:"remotePorts"`
-	RemoteIPs   []string      `json:"remoteIPs"`
+	Mode        string     `json:"mode"`
+	Interval    Int32Range `json:"interval"`
+	RemoteIPs   []string   `json:"remoteIPs"`
+	RemotePorts PortList   `json:"remotePorts"`
 }
 
 func (c *UDPHop) Build() (proto.Message, error) {
-	var sockopt *internet.SocketConfig
-	if c.Sockopt != nil {
-		var err error
-		sockopt, err = c.Sockopt.Build()
-		if err != nil {
-			return nil, err
-		}
-	}
 	var local, remote, remoteOnce bool
 	for _, mode := range strings.Split(c.Mode, ",") {
 		switch strings.ToLower(mode) {
@@ -953,14 +943,13 @@ func (c *UDPHop) Build() (proto.Message, error) {
 		return nil, errors.New("invalid ip ", ip)
 	}
 	return &udphop.Config{
-		Sockopt:     sockopt,
 		Local:       local,
 		Remote:      remote,
 		RemoteOnce:  remoteOnce,
 		IntervalMin: int64(c.Interval.From),
 		IntervalMax: int64(c.Interval.To),
-		RemotePorts: c.RemotePorts.Build().Ports(),
 		RemoteIPs:   remoteIPs,
+		RemotePorts: c.RemotePorts.Build().Ports(),
 	}, nil
 }
 

proxy/wireguard/client.go

@@ -28,6 +28,7 @@ import (
 	"github.com/xtls/xray-core/features/stats"
 	"github.com/xtls/xray-core/transport"
 	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 	"golang.zx2c4.com/wireguard/device"
 )
 
@@ -293,26 +294,26 @@ func (h *Handler) init(ctx context.Context) error {
 		if err != nil {
 			return nil, err
 		}
-		conn, err := internet.DialSystem(ctx, dest, h.streamSettings.SocketSettings)
-		if err != nil {
-			return nil, err
-		}
 		var pktConn net.PacketConn
-		switch c := conn.(type) {
-		case *internet.PacketConnWrapper:
-			pktConn = c.PacketConn
-		case *cnc.Connection:
-			pktConn = &internet.FakePacketConn{Conn: c}
-		default:
-			panic(reflect.TypeOf(c))
-		}
-		if h.streamSettings.UdpmaskManager != nil {
-			newConn, err := h.streamSettings.UdpmaskManager.WrapPacketConnClient(pktConn)
+		if h.streamSettings.FinalMask != nil {
+			conn, err := h.streamSettings.FinalMask.DialUDP(ctx, dest)
 			if err != nil {
-				pktConn.Close()
-				return nil, errors.New("mask err").Base(err)
+				return nil, errors.New("failed to dial to dest").Base(err)
+			}
+			pktConn = conn.(*finalmask.PacketConnWrapper).PacketConn
+		} else {
+			conn, err := internet.DialSystem(ctx, dest, h.streamSettings.SocketSettings)
+			if err != nil {
+				return nil, errors.New("failed to dial to dest").Base(err)
+			}
+			switch c := conn.(type) {
+			case *internet.PacketConnWrapper:
+				pktConn = c.PacketConn
+			case *cnc.Connection:
+				pktConn = &internet.FakePacketConn{Conn: c}
+			default:
+				panic(reflect.TypeOf(c))
 			}
-			pktConn = newConn
 		}
 		if h.uplinkCounter != nil || h.downlinkCounter != nil {
 			pktConn = &PacketCounterConnection{

proxy/wireguard/server.go

@@ -258,18 +258,16 @@ func (s *Server) Start() error {
 		return errors.New("address is domain")
 	}
 	listenFunc := func() (net.PacketConn, error) {
-		pktConn, err := internet.ListenSystemPacket(context.Background(), &net.UDPAddr{IP: s.src.Address.IP(), Port: int(s.src.Port)}, s.streamSettings.SocketSettings)
+		var pktConn net.PacketConn
+		var err error
+		if s.streamSettings.FinalMask != nil {
+			pktConn, err = s.streamSettings.FinalMask.ListenPacket(context.Background(), &net.UDPAddr{IP: s.src.Address.IP(), Port: int(s.src.Port)})
+		} else {
+			pktConn, err = internet.ListenSystemPacket(context.Background(), &net.UDPAddr{IP: s.src.Address.IP(), Port: int(s.src.Port)}, s.streamSettings.SocketSettings)
+		}
 		if err != nil {
 			return nil, err
 		}
-		if s.streamSettings.UdpmaskManager != nil {
-			newConn, err := s.streamSettings.UdpmaskManager.WrapPacketConnServer(pktConn)
-			if err != nil {
-				pktConn.Close()
-				return nil, errors.New("mask err").Base(err)
-			}
-			pktConn = newConn
-		}
 		if s.uplinkCounter != nil || s.downlinkCounter != nil {
 			pktConn = &PacketCounterConnection{
 				PacketConn:   pktConn,

testing/scenarios/wireguard_test.go

@@ -65,6 +65,7 @@ func TestWireguard(t *testing.T) {
 				ProxySettings: serial.ToTypedMessage(&freedom.Config{
 					FinalRules: []*freedom.FinalRuleConfig{{Action: freedom.RuleAction_Allow}},
 				}),
+				SenderSettings: serial.ToTypedMessage(&proxyman.SenderConfig{}),
 			},
 		},
 	}
@@ -104,6 +105,7 @@ func TestWireguard(t *testing.T) {
 						AllowedIps: []string{"0.0.0.0/0", "::0/0"},
 					}},
 				}),
+				SenderSettings: serial.ToTypedMessage(&proxyman.SenderConfig{}),
 			},
 		},
 	}

transport/internet/finalmask/finalmask.go

@@ -2,103 +2,291 @@ package finalmask
 
 import (
 	"context"
-	"net"
+	"fmt"
 	"slices"
 
 	"github.com/xtls/xray-core/common/buf"
 	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/net"
 )
 
-type Udpmask interface {
-	WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error)
-	WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error)
+type Dialer struct {
+	DialTCP func(net.Destination) (net.Conn, error)
+	DialUDP func(net.Destination) (net.Conn, error)
 }
 
-type UdpmaskManager struct {
-	udpmasks []Udpmask
+type ListenConfig struct {
+	Listen       func(net.Addr) (net.Listener, error)
+	ListenPacket func(net.Addr) (net.PacketConn, error)
 }
 
-func NewUdpmaskManager(udpmasks []Udpmask) *UdpmaskManager {
-	slices.Reverse(udpmasks)
-	return &UdpmaskManager{udpmasks: udpmasks}
+type TCPMask interface {
+	WrapConnClient(net.Conn, *net.Destination, *Dialer) (net.Conn, error)
+	WrapConnServer(net.Conn) (net.Conn, error)
+	// Listen(net.Listener) (net.Listener, error)
 }
 
-func (m *UdpmaskManager) WrapPacketConnClient(raw net.PacketConn) (net.PacketConn, error) {
-	var sizes []int
-	var conns []net.PacketConn
-	for i, mask := range m.udpmasks {
-		if _, ok := mask.(headerConn); ok {
-			conn, err := mask.WrapPacketConnClient(nil, i, len(m.udpmasks)-1)
-			if err != nil {
-				return nil, err
-			}
-			sizes = append(sizes, conn.(headerSize).Size())
-			conns = append(conns, conn)
-		} else {
-			if len(conns) > 0 {
-				raw = &headerManagerConn{sizes: sizes, conns: conns, PacketConn: raw}
-				sizes = nil
-				conns = nil
-			}
-			var err error
-			raw, err = mask.WrapPacketConnClient(raw, i, len(m.udpmasks)-1)
-			if err != nil {
-				return nil, err
+type UDPMask interface {
+	WrapPacketConnClient(net.PacketConn, *net.Destination, *Dialer) (net.PacketConn, error)
+	WrapPacketConnServer(net.PacketConn, net.Addr, *ListenConfig) (net.PacketConn, error)
+}
+
+type FinalMask struct {
+	tcpMasks     []TCPMask
+	udpMasks     []UDPMask
+	dialTCP      func(context.Context, net.Destination) (net.Conn, error)
+	listen       func(context.Context, net.Addr) (net.Listener, error)
+	dialUDP      func(context.Context, net.Destination) (net.PacketConn, net.Addr, error)
+	listenPacket func(context.Context, net.Addr) (net.PacketConn, error)
+}
+
+func NewFinalMask(tcpMasks []TCPMask, udpMasks []UDPMask, dialTCP func(context.Context, net.Destination) (net.Conn, error), listen func(context.Context, net.Addr) (net.Listener, error), dialUDP func(context.Context, net.Destination) (net.PacketConn, net.Addr, error), listenPacket func(context.Context, net.Addr) (net.PacketConn, error)) *FinalMask {
+	slices.Reverse(tcpMasks)
+	slices.Reverse(udpMasks)
+	return &FinalMask{
+		tcpMasks:     tcpMasks,
+		udpMasks:     udpMasks,
+		dialTCP:      dialTCP,
+		dialUDP:      dialUDP,
+		listen:       listen,
+		listenPacket: listenPacket,
+	}
+}
+
+func (fm *FinalMask) DialTCP(ctx context.Context, dest net.Destination) (net.Conn, error) {
+	if len(fm.tcpMasks) == 0 {
+		return fm.dialTCP(ctx, dest)
+	}
+	for i := range fm.tcpMasks {
+		if i > 0 {
+			if _, ok := fm.tcpMasks[i].(interface{ HandleDial() }); ok {
+				return nil, fmt.Errorf("incorrect index: %d %T", i, fm.tcpMasks[i])
 			}
 		}
 	}
-
-	if len(conns) > 0 {
-		raw = &headerManagerConn{sizes: sizes, conns: conns, PacketConn: raw}
-		sizes = nil
-		conns = nil
+	var conn net.Conn
+	var err error
+	if _, ok := fm.tcpMasks[0].(interface{ HandleDial() }); !ok {
+		conn, err = fm.dialTCP(ctx, dest)
+		if err != nil {
+			return nil, err
+		}
 	}
-	return raw, nil
+	dialer := &Dialer{
+		DialTCP: func(dest net.Destination) (net.Conn, error) {
+			return fm.dialTCP(ctx, dest)
+		},
+		DialUDP: func(dest net.Destination) (net.Conn, error) {
+			conn, addr, err := fm.dialUDP(ctx, dest)
+			if err != nil {
+				return nil, err
+			}
+			return &PacketConnWrapper{PacketConn: conn, udpAddr: addr}, err
+		},
+	}
+	for i := range fm.tcpMasks {
+		var newConn net.Conn
+		newConn, err = fm.tcpMasks[i].WrapConnClient(conn, &dest, dialer)
+		if err != nil {
+			_ = conn.Close()
+			return nil, err
+		}
+		conn = newConn
+	}
+	return conn, nil
 }
 
-func (m *UdpmaskManager) WrapPacketConnServer(raw net.PacketConn) (net.PacketConn, error) {
-	var sizes []int
-	var conns []net.PacketConn
-	for i, mask := range m.udpmasks {
-		if _, ok := mask.(headerConn); ok {
-			conn, err := mask.WrapPacketConnServer(nil, i, len(m.udpmasks)-1)
-			if err != nil {
-				return nil, err
+func (fm *FinalMask) Listen(ctx context.Context, addr net.Addr) (net.Listener, error) {
+	if len(fm.tcpMasks) == 0 {
+		return fm.listen(ctx, addr)
+	}
+	off := 0
+	listener, err := fm.listen(ctx, addr)
+	if err != nil {
+		return nil, err
+	}
+	for i := range fm.tcpMasks {
+		if _, ok := fm.tcpMasks[i].(interface {
+			Listen(net.Listener) (net.Listener, error)
+		}); ok {
+			if i-off == 0 {
+				l, err := fm.tcpMasks[i].(interface {
+					Listen(net.Listener) (net.Listener, error)
+				}).Listen(listener)
+				if err != nil {
+					listener.Close()
+					return nil, err
+				}
+				listener = l
+			} else {
+				l, err := fm.tcpMasks[i].(interface {
+					Listen(net.Listener) (net.Listener, error)
+				}).Listen(&TCPListener{Listener: listener, tcpMasks: fm.tcpMasks[off:i]})
+				if err != nil {
+					listener.Close()
+					return nil, err
+				}
+				listener = l
 			}
-			sizes = append(sizes, conn.(headerSize).Size())
-			conns = append(conns, conn)
-		} else {
-			if len(conns) > 0 {
-				raw = &headerManagerConn{sizes: sizes, conns: conns, PacketConn: raw}
-				sizes = nil
-				conns = nil
-			}
-			var err error
-			raw, err = mask.WrapPacketConnServer(raw, i, len(m.udpmasks)-1)
-			if err != nil {
-				return nil, err
+			off = i + 1
+		}
+	}
+	if off < len(fm.tcpMasks) {
+		return &TCPListener{Listener: listener, tcpMasks: fm.tcpMasks[off:]}, nil
+	}
+	return listener, nil
+}
+
+func (fm *FinalMask) DialUDP(ctx context.Context, dest net.Destination) (net.Conn, error) {
+	if len(fm.udpMasks) == 0 {
+		conn, addr, err := fm.dialUDP(ctx, dest)
+		if err != nil {
+			return nil, err
+		}
+		return &PacketConnWrapper{PacketConn: conn, udpAddr: addr}, nil
+	}
+	for i := range fm.udpMasks {
+		if i > 0 {
+			if _, ok := fm.udpMasks[i].(interface{ HandleDial() }); ok {
+				return nil, fmt.Errorf("incorrect index: %d %T", i, fm.udpMasks[i])
 			}
 		}
 	}
-
+	var conn net.PacketConn
+	var addr net.Addr
+	var err error
+	if _, ok := fm.udpMasks[0].(interface{ HandleDial() }); !ok {
+		conn, addr, err = fm.dialUDP(ctx, dest)
+		if err != nil {
+			return nil, err
+		}
+	}
+	dialer := &Dialer{
+		DialTCP: func(dest net.Destination) (net.Conn, error) {
+			return fm.dialTCP(ctx, dest)
+		},
+		DialUDP: func(dest net.Destination) (net.Conn, error) {
+			conn, addr, err := fm.dialUDP(ctx, dest)
+			if err != nil {
+				return nil, err
+			}
+			return &PacketConnWrapper{PacketConn: conn, udpAddr: addr}, err
+		},
+	}
+	var sizes []int
+	var conns []net.PacketConn
+	for i := range fm.udpMasks {
+		var newConn net.PacketConn
+		if _, ok := fm.udpMasks[i].(interface{ HeaderConn() }); ok {
+			newConn, err = fm.udpMasks[i].WrapPacketConnClient(nil, nil, nil)
+			if err != nil {
+				_ = conn.Close()
+				return nil, err
+			}
+			sizes = append(sizes, newConn.(interface{ Size() int }).Size())
+			conns = append(conns, newConn)
+		} else {
+			if len(conns) > 0 {
+				conn = &headerManagerConn{PacketConn: conn, sizes: sizes, conns: conns}
+				sizes = nil
+				conns = nil
+			}
+			newConn, err = fm.udpMasks[i].WrapPacketConnClient(conn, &dest, dialer)
+			if err != nil {
+				_ = conn.Close()
+				return nil, err
+			}
+			conn = newConn
+		}
+	}
 	if len(conns) > 0 {
-		raw = &headerManagerConn{sizes: sizes, conns: conns, PacketConn: raw}
+		conn = &headerManagerConn{PacketConn: conn, sizes: sizes, conns: conns}
 		sizes = nil
 		conns = nil
 	}
-	return raw, nil
+	if addr == nil {
+		addr = &net.UDPAddr{IP: []byte{0, 0, 0, 0}}
+	}
+	return &PacketConnWrapper{PacketConn: conn, udpAddr: addr}, nil
+}
+
+func (fm *FinalMask) ListenPacket(ctx context.Context, addr net.Addr) (net.PacketConn, error) {
+	if len(fm.udpMasks) == 0 {
+		return fm.listenPacket(ctx, addr)
+	}
+	for i := range fm.udpMasks {
+		if i > 0 {
+			if _, ok := fm.udpMasks[i].(interface{ HandleListen() }); ok {
+				return nil, fmt.Errorf("incorrect index: %d %T", i, fm.udpMasks[i])
+			}
+		}
+	}
+	var conn net.PacketConn
+	var err error
+	if _, ok := fm.udpMasks[0].(interface{ HandleListen() }); !ok {
+		conn, err = fm.listenPacket(ctx, addr)
+		if err != nil {
+			return nil, err
+		}
+	}
+	lc := &ListenConfig{
+		Listen:       func(addr net.Addr) (net.Listener, error) { return fm.listen(ctx, addr) },
+		ListenPacket: func(addr net.Addr) (net.PacketConn, error) { return fm.listenPacket(ctx, addr) },
+	}
+	var sizes []int
+	var conns []net.PacketConn
+	for i := range fm.udpMasks {
+		var newConn net.PacketConn
+		if _, ok := fm.udpMasks[i].(interface{ HeaderConn() }); ok {
+			newConn, err = fm.udpMasks[i].WrapPacketConnServer(nil, nil, nil)
+			if err != nil {
+				_ = conn.Close()
+				return nil, err
+			}
+			sizes = append(sizes, newConn.(interface{ Size() int }).Size())
+			conns = append(conns, newConn)
+		} else {
+			if len(conns) > 0 {
+				conn = &headerManagerConn{PacketConn: conn, sizes: sizes, conns: conns}
+				sizes = nil
+				conns = nil
+			}
+			newConn, err = fm.udpMasks[i].WrapPacketConnServer(conn, addr, lc)
+			if err != nil {
+				_ = conn.Close()
+				return nil, err
+			}
+			conn = newConn
+		}
+	}
+	if len(conns) > 0 {
+		conn = &headerManagerConn{PacketConn: conn, sizes: sizes, conns: conns}
+		sizes = nil
+		conns = nil
+	}
+	return conn, nil
 }
 
 const (
 	UDPSize = 4096
 )
 
-type headerConn interface {
-	HeaderConn()
+type PacketConnWrapper struct {
+	net.PacketConn
+	udpAddr net.Addr
 }
 
-type headerSize interface {
-	Size() int
+func (c *PacketConnWrapper) RemoteAddr() net.Addr {
+	return c.udpAddr
+}
+
+func (c *PacketConnWrapper) Read(b []byte) (n int, err error) {
+	n, _, err = c.PacketConn.ReadFrom(b)
+	return
+}
+
+func (c *PacketConnWrapper) Write(b []byte) (n int, err error) {
+	return c.PacketConn.WriteTo(b, c.udpAddr)
 }
 
 type headerManagerConn struct {
@@ -191,72 +379,27 @@ func (c *headerManagerConn) WriteTo(p []byte, addr net.Addr) (n int, err error)
 	return len(p), nil
 }
 
-type Tcpmask interface {
-	WrapConnClient(net.Conn) (net.Conn, error)
-	WrapConnServer(net.Conn) (net.Conn, error)
-}
-
-type TcpmaskManager struct {
-	tcpmasks []Tcpmask
-}
-
-func NewTcpmaskManager(tcpmasks []Tcpmask) *TcpmaskManager {
-	slices.Reverse(tcpmasks)
-	return &TcpmaskManager{tcpmasks: tcpmasks}
-}
-
-func (m *TcpmaskManager) WrapConnClient(raw net.Conn) (net.Conn, error) {
-	var err error
-	for _, mask := range m.tcpmasks {
-		raw, err = mask.WrapConnClient(raw)
-		if err != nil {
-			return nil, err
-		}
-	}
-	return raw, nil
-}
-
-func (m *TcpmaskManager) WrapConnServer(raw net.Conn) (net.Conn, error) {
-	var err error
-	for _, mask := range m.tcpmasks {
-		raw, err = mask.WrapConnServer(raw)
-		if err != nil {
-			return nil, err
-		}
-	}
-	return raw, nil
-}
-
-func (m *TcpmaskManager) WrapListener(l net.Listener) (net.Listener, error) {
-	return NewTcpListener(m, l)
-}
-
-type tcpListener struct {
-	m *TcpmaskManager
+type TCPListener struct {
 	net.Listener
+	tcpMasks []TCPMask
 }
 
-func NewTcpListener(m *TcpmaskManager, l net.Listener) (net.Listener, error) {
-	return &tcpListener{
-		m:        m,
-		Listener: l,
-	}, nil
-}
-
-func (l *tcpListener) Accept() (net.Conn, error) {
+func (l *TCPListener) Accept() (net.Conn, error) {
 	conn, err := l.Listener.Accept()
 	if err != nil {
 		return conn, err
 	}
 
-	newConn, err := l.m.WrapConnServer(conn)
-	if err != nil {
-		errors.LogDebugInner(context.Background(), err, "mask err")
-		_ = conn.Close()
-		return nil, err
+	for i := range l.tcpMasks {
+		var newConn net.Conn
+		newConn, err = l.tcpMasks[i].WrapConnServer(conn)
+		if err != nil {
+			_ = conn.Close()
+			return nil, err
+		}
+		conn = newConn
 	}
-
-	return newConn, nil
+	return conn, nil
 }
 
 type TcpMaskConn interface {

transport/internet/finalmask/fragment/config.go

@@ -1,11 +1,14 @@
 package fragment
 
-import "net"
+import (
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
+)
 
-func (c *Config) WrapConnClient(raw net.Conn) (net.Conn, error) {
-	return NewConnClient(c, raw, false)
+func (c *Config) WrapConnClient(conn net.Conn, dest *net.Destination, dialer *finalmask.Dialer) (net.Conn, error) {
+	return NewConnClient(c, conn, false)
 }
 
-func (c *Config) WrapConnServer(raw net.Conn) (net.Conn, error) {
-	return NewConnServer(c, raw, true)
+func (c *Config) WrapConnServer(conn net.Conn) (net.Conn, error) {
+	return NewConnServer(c, conn, true)
 }

transport/internet/finalmask/header/custom/config.go

@@ -1,29 +1,30 @@
 package custom
 
 import (
-	"net"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
-func (c *TCPConfig) WrapConnClient(raw net.Conn) (net.Conn, error) {
-	return NewConnClientTCP(c, raw)
+func (c *TCPConfig) WrapConnClient(conn net.Conn, dest *net.Destination, dialer *finalmask.Dialer) (net.Conn, error) {
+	return NewConnClientTCP(c, conn)
 }
 
-func (c *TCPConfig) WrapConnServer(raw net.Conn) (net.Conn, error) {
-	return NewConnServerTCP(c, raw)
+func (c *TCPConfig) WrapConnServer(conn net.Conn) (net.Conn, error) {
+	return NewConnServerTCP(c, conn)
 }
 
-func (c *UDPConfig) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnClientUDP(c, raw)
+func (c *UDPConfig) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewConnClientUDP(c, conn)
 }
 
-func (c *UDPConfig) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnServerUDP(c, raw)
+func (c *UDPConfig) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServerUDP(c, conn)
 }
 
-func (c *UDPStandaloneConfig) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnClientUDPStandalone(c, raw)
+func (c *UDPStandaloneConfig) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewConnClientUDPStandalone(c, conn)
 }
 
-func (c *UDPStandaloneConfig) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnServerUDPStandalone(c, raw)
+func (c *UDPStandaloneConfig) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServerUDPStandalone(c, conn)
 }

transport/internet/finalmask/header/custom/metadata_test.go

@@ -9,8 +9,6 @@ import (
 	"strings"
 	"testing"
 	"time"
-
-	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
 func TestMetadataEvaluatorRejectsUnknownName(t *testing.T) {
@@ -156,7 +154,7 @@ func TestMetadataUDPStandaloneWriteUsesRemotePort(t *testing.T) {
 	}
 	defer serverRaw.Close()
 
-	client, err := finalmask.NewUdpmaskManager([]finalmask.Udpmask{cfg}).WrapPacketConnClient(clientRaw)
+	client, err := cfg.WrapPacketConnClient(clientRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -301,7 +299,7 @@ func TestMetadataTCPHandshakeUsesEndpointPorts(t *testing.T) {
 	}
 	defer serverRaw.Close()
 
-	client, err := clientCfg.WrapConnClient(clientRaw)
+	client, err := clientCfg.WrapConnClient(clientRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}

transport/internet/finalmask/header/custom/state_test.go

@@ -5,8 +5,6 @@ import (
 	"net"
 	"testing"
 	"time"
-
-	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
 func mustSendRecvUDP(t *testing.T, from net.PacketConn, to net.PacketConn, msg []byte) {
@@ -48,7 +46,6 @@ func TestStateUDPResponseReusesPriorCapturedValues(t *testing.T) {
 			},
 		},
 	}
-	maskManager := finalmask.NewUdpmaskManager([]finalmask.Udpmask{cfg})
 
 	clientRaw, err := net.ListenPacket("udp", "127.0.0.1:0")
 	if err != nil {
@@ -62,11 +59,11 @@ func TestStateUDPResponseReusesPriorCapturedValues(t *testing.T) {
 	}
 	defer serverRaw.Close()
 
-	client, err := maskManager.WrapPacketConnClient(clientRaw)
+	client, err := cfg.WrapPacketConnClient(clientRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
-	server, err := maskManager.WrapPacketConnServer(serverRaw)
+	server, err := cfg.WrapPacketConnServer(serverRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}

transport/internet/finalmask/header/custom/tcp_runtime_test.go

@@ -37,7 +37,7 @@ func TestDSLTCPHandshakeReusesCapturedValue(t *testing.T) {
 	defer clientRaw.Close()
 	defer serverRaw.Close()
 
-	client, err := cfg.WrapConnClient(clientRaw)
+	client, err := cfg.WrapConnClient(clientRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -117,7 +117,7 @@ func TestDSLTCPClientRejectsMismatchedResponseSequence(t *testing.T) {
 	defer clientRaw.Close()
 	defer serverRaw.Close()
 
-	client, err := clientCfg.WrapConnClient(clientRaw)
+	client, err := clientCfg.WrapConnClient(clientRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}

transport/internet/finalmask/mkcp/aes128gcm/config.go

@@ -1,15 +1,16 @@
 package aes128gcm
 
 import (
-	"net"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
 func (c *Config) HeaderConn() {}
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnClient(c, raw)
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewConnClient(c, conn)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnServer(c, raw)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServer(c, conn)
 }

transport/internet/finalmask/mkcp/header/config.go

@@ -1,15 +1,16 @@
 package header
 
 import (
-	"net"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
 func (c *Config) HeaderConn() {}
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnClient(c, raw)
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewConnClient(c, conn)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnServer(c, raw)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServer(c, conn)
 }

transport/internet/finalmask/mkcp/original/config.go

@@ -1,15 +1,16 @@
 package original
 
 import (
-	"net"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
 func (c *Config) HeaderConn() {}
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnClient(c, raw)
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewConnClient(c, conn)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnServer(c, raw)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServer(c, conn)
 }

transport/internet/finalmask/noise/config.go

@@ -1,11 +1,14 @@
 package noise
 
-import "net"
+import (
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
+)
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnClient(c, raw)
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewConnClient(c, conn)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewConnServer(c, raw)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServer(c, conn)
 }

transport/internet/finalmask/realm/config.go

@@ -1,23 +1,14 @@
 package realm
 
 import (
-	"net"
-
-	"github.com/xtls/xray-core/common/errors"
-	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	_, ok1 := raw.(*internet.FakePacketConn)
-	if level != 0 || ok1 {
-		return nil, errors.New("realm requires being at the outermost level")
-	}
-	return NewConnClient(c, raw)
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewConnClient(c, conn)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	if level != 0 {
-		return nil, errors.New("realm requires being at the outermost level")
-	}
-	return NewConnServer(c, raw)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServer(c, conn)
 }

transport/internet/finalmask/salamander/config.go

@@ -1,23 +1,24 @@
 package salamander
 
 import (
-	"net"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
 func (c *Config) HeaderConn() {}
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewSalamanderConnClient(c, raw)
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewSalamanderConnClient(c, conn)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewSalamanderConnServer(c, raw)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewSalamanderConnServer(c, conn)
 }
 
-func (c *GeckoConfig) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewGeckoConnClient(c, raw)
+func (c *GeckoConfig) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewGeckoConnClient(c, conn)
 }
 
-func (c *GeckoConfig) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	return NewGeckoConnServer(c, raw)
+func (c *GeckoConfig) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewGeckoConnServer(c, conn)
 }

transport/internet/finalmask/sudoku/config.go

@@ -1,19 +1,18 @@
 package sudoku
 
 import (
-	"net"
-
-	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
 // Sudoku in finalmask mode is a pure appearance transform with no standalone handshake.
 // TCP always keeps classic sudoku on uplink and uses packed downlink optimization on server writes.
-func (c *Config) WrapConnClient(raw net.Conn) (net.Conn, error) {
-	return newPackedDirectionalConn(raw, c, true)
+func (c *Config) WrapConnClient(conn net.Conn, dest *net.Destination, dialer *finalmask.Dialer) (net.Conn, error) {
+	return newPackedDirectionalConn(conn, c, true)
 }
 
-func (c *Config) WrapConnServer(raw net.Conn) (net.Conn, error) {
-	return newPackedDirectionalConn(raw, c, false)
+func (c *Config) WrapConnServer(conn net.Conn) (net.Conn, error) {
+	return newPackedDirectionalConn(conn, c, false)
 }
 
 func newPackedDirectionalConn(raw net.Conn, config *Config, readPacked bool) (net.Conn, error) {
@@ -36,16 +35,10 @@ func newPackedDirectionalConn(raw net.Conn, config *Config, readPacked bool) (ne
 	return newWrappedConn(raw, reader, writer), nil
 }
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	if level != levelCount {
-		return nil, errors.New("sudoku udp mask must be the innermost mask in chain")
-	}
-	return NewUDPConn(raw, c)
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewUDPConn(conn, c)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	if level != levelCount {
-		return nil, errors.New("sudoku udp mask must be the innermost mask in chain")
-	}
-	return NewUDPConn(raw, c)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewUDPConn(conn, c)
 }

transport/internet/finalmask/tcp_test.go

@@ -2,12 +2,14 @@ package finalmask_test
 
 import (
 	"bytes"
+	"context"
 	"io"
-	"net"
+	gonet "net"
 	"strings"
 	"testing"
 	"time"
 
+	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/transport/internet/finalmask"
 	"github.com/xtls/xray-core/transport/internet/finalmask/header/custom"
 )
@@ -20,11 +22,14 @@ func mustSendRecvTcp(
 ) {
 	t.Helper()
 
+	waitCh := make(chan error)
+
 	go func() {
 		_, err := from.Write(msg)
 		if err != nil {
-			t.Error(err)
+			t.Fatal(err)
 		}
+		close(waitCh)
 	}()
 
 	buf := make([]byte, 1024)
@@ -40,18 +45,23 @@ func mustSendRecvTcp(
 	if !bytes.Equal(buf[:n], msg) {
 		t.Fatalf("unexpected data %q", buf[:n])
 	}
+
+	<-waitCh
 }
 
 type layerMaskTcp struct {
 	name string
-	mask finalmask.Tcpmask
+	mask finalmask.TCPMask
 }
 
 type failingWrapMask struct{}
 
-func (failingWrapMask) TCP()                                            {}
-func (f failingWrapMask) WrapConnClient(raw net.Conn) (net.Conn, error) { return raw, nil }
-func (f failingWrapMask) WrapConnServer(raw net.Conn) (net.Conn, error) {
+func (failingWrapMask) TCP() {}
+func (f failingWrapMask) WrapConnClient(conn net.Conn, dest *net.Destination, dialer *finalmask.Dialer) (net.Conn, error) {
+	return conn, nil
+}
+
+func (f failingWrapMask) WrapConnServer(conn net.Conn) (net.Conn, error) {
 	return nil, io.ErrClosedPipe
 }
 
@@ -92,32 +102,31 @@ func TestConnReadWrite(t *testing.T) {
 		t.Run(c.name, func(t *testing.T) {
 			mask := c.mask
 
-			maskManager := finalmask.NewTcpmaskManager([]finalmask.Tcpmask{mask})
+			dialTCP := func(ctx context.Context, dest net.Destination) (net.Conn, error) {
+				return net.Dial("tcp", dest.NetAddr())
+			}
+			listen := func(ctx context.Context, addr net.Addr) (net.Listener, error) {
+				return net.Listen("tcp", addr.String())
+			}
+			finalMask := finalmask.NewFinalMask([]finalmask.TCPMask{mask}, nil, dialTCP, listen, nil, nil)
 
-			ln, err := net.Listen("tcp", "127.0.0.1:0")
+			listener, err := finalMask.Listen(context.Background(), &net.TCPAddr{IP: net.LocalHostIP.IP()})
 			if err != nil {
 				t.Fatal(err)
 			}
+			t.Cleanup(func() { listener.Close() })
 
-			client, err := net.Dial("tcp", ln.Addr().String())
+			client, err := finalMask.DialTCP(context.Background(), net.TCPDestination(net.IPAddress(listener.Addr().(*net.TCPAddr).IP), net.Port(listener.Addr().(*net.TCPAddr).Port)))
 			if err != nil {
 				t.Fatal(err)
 			}
+			t.Cleanup(func() { client.Close() })
 
-			client, err = maskManager.WrapConnClient(client)
-			if err != nil {
-				t.Fatal(err)
-			}
-
-			server, err := ln.Accept()
-			if err != nil {
-				t.Fatal(err)
-			}
-
-			server, err = maskManager.WrapConnServer(server)
+			server, err := listener.Accept()
 			if err != nil {
 				t.Fatal(err)
 			}
+			t.Cleanup(func() { server.Close() })
 
 			_ = client.SetDeadline(time.Now().Add(time.Second))
 			_ = server.SetDeadline(time.Now().Add(time.Second))
@@ -150,34 +159,32 @@ func TestTCPcustomStaticHandshakeRoundTrip(t *testing.T) {
 			},
 		},
 	}
-	maskManager := finalmask.NewTcpmaskManager([]finalmask.Tcpmask{cfg})
 
-	ln, err := net.Listen("tcp", "127.0.0.1:0")
-	if err != nil {
-		t.Fatal(err)
+	dialTCP := func(ctx context.Context, dest net.Destination) (net.Conn, error) {
+		return net.Dial("tcp", dest.NetAddr())
 	}
-	defer ln.Close()
+	listen := func(ctx context.Context, addr net.Addr) (net.Listener, error) {
+		return net.Listen("tcp", addr.String())
+	}
+	finalMask := finalmask.NewFinalMask([]finalmask.TCPMask{cfg}, nil, dialTCP, listen, nil, nil)
 
-	clientRaw, err := net.Dial("tcp", ln.Addr().String())
+	listener, err := finalMask.Listen(context.Background(), &net.TCPAddr{IP: net.LocalHostIP.IP()})
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer clientRaw.Close()
+	defer listener.Close()
 
-	serverRaw, err := ln.Accept()
+	client, err := finalMask.DialTCP(context.Background(), net.TCPDestination(net.IPAddress(listener.Addr().(*net.TCPAddr).IP), net.Port(listener.Addr().(*net.TCPAddr).Port)))
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer serverRaw.Close()
+	defer client.Close()
 
-	client, err := maskManager.WrapConnClient(clientRaw)
-	if err != nil {
-		t.Fatal(err)
-	}
-	server, err := maskManager.WrapConnServer(serverRaw)
+	server, err := listener.Accept()
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer server.Close()
 
 	_ = client.SetDeadline(time.Now().Add(time.Second))
 	_ = server.SetDeadline(time.Now().Add(time.Second))
@@ -220,11 +227,11 @@ func TestTCPcustomClientRejectsMismatchedServerSequence(t *testing.T) {
 		},
 	}
 
-	clientRaw, serverRaw := net.Pipe()
+	clientRaw, serverRaw := gonet.Pipe()
 	defer clientRaw.Close()
 	defer serverRaw.Close()
 
-	client, err := clientCfg.WrapConnClient(clientRaw)
+	client, err := clientCfg.WrapConnClient(clientRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -257,42 +264,37 @@ func TestTCPcustomClientRejectsMismatchedServerSequence(t *testing.T) {
 }
 
 func TestTCPWrapListenerRejectsImmediateWrapErrors(t *testing.T) {
-	clientManager := finalmask.NewTcpmaskManager([]finalmask.Tcpmask{failingWrapMask{}})
-	serverManager := finalmask.NewTcpmaskManager([]finalmask.Tcpmask{failingWrapMask{}})
+	dialTCP := func(ctx context.Context, dest net.Destination) (net.Conn, error) {
+		return net.Dial("tcp", dest.NetAddr())
+	}
+	listen := func(ctx context.Context, addr net.Addr) (net.Listener, error) {
+		return net.Listen("tcp", addr.String())
+	}
+	finalMask := finalmask.NewFinalMask([]finalmask.TCPMask{failingWrapMask{}}, nil, dialTCP, listen, nil, nil)
 
-	rawLn, err := net.Listen("tcp", "127.0.0.1:0")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer rawLn.Close()
-
-	ln, err := serverManager.WrapListener(rawLn)
+	listener, err := finalMask.Listen(context.Background(), &net.TCPAddr{IP: net.LocalHostIP.IP()})
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer listener.Close()
 
 	accepted := make(chan struct {
 		conn net.Conn
 		err  error
 	}, 1)
 	go func() {
-		conn, err := ln.Accept()
+		conn, err := listener.Accept()
 		accepted <- struct {
 			conn net.Conn
 			err  error
 		}{conn: conn, err: err}
 	}()
 
-	clientRaw, err := net.Dial("tcp", rawLn.Addr().String())
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer clientRaw.Close()
-
-	client, err := clientManager.WrapConnClient(clientRaw)
+	client, err := finalMask.DialTCP(context.Background(), net.TCPDestination(net.IPAddress(listener.Addr().(*net.TCPAddr).IP), net.Port(listener.Addr().(*net.TCPAddr).Port)))
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer client.Close()
 
 	_ = client.SetDeadline(time.Now().Add(time.Second))
 

transport/internet/finalmask/udp_test.go

@@ -2,13 +2,15 @@ package finalmask_test
 
 import (
 	"bytes"
+	"context"
 	"encoding/binary"
 	"io"
-	"net"
+	gonet "net"
 	"sync/atomic"
 	"testing"
 	"time"
 
+	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/proxy"
 	"github.com/xtls/xray-core/transport/internet/finalmask"
 	"github.com/xtls/xray-core/transport/internet/finalmask/header/custom"
@@ -51,7 +53,7 @@ func mustSendRecv(
 
 type layerMask struct {
 	name   string
-	mask   finalmask.Udpmask
+	mask   finalmask.UDPMask
 	layers int
 }
 
@@ -213,25 +215,23 @@ func newStandaloneStunLikeUDPServerConfig() *custom.UDPStandaloneConfig {
 func newUDPClientServerPair(t *testing.T, cfg *custom.UDPStandaloneConfig) (net.PacketConn, net.PacketConn, net.PacketConn, net.PacketConn) {
 	t.Helper()
 
-	clientRaw, err := net.ListenPacket("udp", "127.0.0.1:0")
+	clientRaw, err := gonet.ListenPacket("udp", "127.0.0.1:0")
 	if err != nil {
 		t.Fatal(err)
 	}
 	t.Cleanup(func() { _ = clientRaw.Close() })
 
-	serverRaw, err := net.ListenPacket("udp", "127.0.0.1:0")
+	serverRaw, err := gonet.ListenPacket("udp", "127.0.0.1:0")
 	if err != nil {
 		t.Fatal(err)
 	}
 	t.Cleanup(func() { _ = serverRaw.Close() })
 
-	maskManager := finalmask.NewUdpmaskManager([]finalmask.Udpmask{cfg})
-
-	client, err := maskManager.WrapPacketConnClient(clientRaw)
+	client, err := cfg.WrapPacketConnClient(clientRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
-	server, err := maskManager.WrapPacketConnServer(serverRaw)
+	server, err := cfg.WrapPacketConnServer(serverRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -348,31 +348,39 @@ func TestPacketConnReadWrite(t *testing.T) {
 			if layers <= 0 {
 				layers = 1
 			}
-			masks := make([]finalmask.Udpmask, 0, layers)
+			masks := make([]finalmask.UDPMask, 0, layers)
 			for i := 0; i < layers; i++ {
 				masks = append(masks, mask)
 			}
-			maskManager := finalmask.NewUdpmaskManager(masks)
 
-			client, err := net.ListenPacket("udp", "127.0.0.1:0")
+			dialUDP := func(ctx context.Context, dest net.Destination) (net.PacketConn, net.Addr, error) {
+				udpAddr, err := net.ResolveUDPAddr("udp", dest.NetAddr())
+				if err != nil {
+					return nil, nil, err
+				}
+				conn, err := gonet.ListenPacket("udp", "127.0.0.1:0")
+				if err != nil {
+					return nil, nil, err
+				}
+				return conn, udpAddr, nil
+			}
+			listenPacket := func(ctx context.Context, addr net.Addr) (net.PacketConn, error) {
+				return gonet.ListenPacket(addr.Network(), addr.String())
+			}
+			finalMask := finalmask.NewFinalMask(nil, masks, nil, nil, dialUDP, listenPacket)
+
+			server, err := finalMask.ListenPacket(context.Background(), &net.UDPAddr{IP: net.LocalHostIP.IP()})
 			if err != nil {
 				t.Fatal(err)
 			}
+			t.Cleanup(func() { server.Close() })
 
-			client, err = maskManager.WrapPacketConnClient(client)
-			if err != nil {
-				t.Fatal(err)
-			}
-
-			server, err := net.ListenPacket("udp", "127.0.0.1:0")
-			if err != nil {
-				t.Fatal(err)
-			}
-
-			server, err = maskManager.WrapPacketConnServer(server)
+			clientConn, err := finalMask.DialUDP(context.Background(), net.UDPDestination(net.IPAddress(server.LocalAddr().(*net.UDPAddr).IP), net.Port(server.LocalAddr().(*net.UDPAddr).Port)))
 			if err != nil {
 				t.Fatal(err)
 			}
+			t.Cleanup(func() { clientConn.Close() })
+			client := clientConn.(*finalmask.PacketConnWrapper).PacketConn
 
 			_ = client.SetDeadline(time.Now().Add(time.Second))
 			_ = server.SetDeadline(time.Now().Add(time.Second))
@@ -397,21 +405,20 @@ func TestUDPcustomStaticHeaderWireShape(t *testing.T) {
 			{Rand: 1, RandMin: 0x30, RandMax: 0x40},
 		},
 	}
-	maskManager := finalmask.NewUdpmaskManager([]finalmask.Udpmask{cfg})
 
-	clientRaw, err := net.ListenPacket("udp", "127.0.0.1:0")
+	clientRaw, err := gonet.ListenPacket("udp", "127.0.0.1:0")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer clientRaw.Close()
 
-	serverRaw, err := net.ListenPacket("udp", "127.0.0.1:0")
+	serverRaw, err := gonet.ListenPacket("udp", "127.0.0.1:0")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer serverRaw.Close()
 
-	client, err := maskManager.WrapPacketConnClient(clientRaw)
+	client, err := cfg.WrapPacketConnClient(clientRaw, nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -642,11 +649,11 @@ func TestSudokuBDD(t *testing.T) {
 			Ascii:    "prefer_ascii",
 		}
 
-		clientRaw, serverRaw := net.Pipe()
+		clientRaw, serverRaw := gonet.Pipe()
 		defer clientRaw.Close()
 		defer serverRaw.Close()
 
-		clientConn, err := cfg.WrapConnClient(clientRaw)
+		clientConn, err := cfg.WrapConnClient(clientRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -683,11 +690,11 @@ func TestSudokuBDD(t *testing.T) {
 			PaddingMax: 0,
 		}
 
-		clientRaw, serverRaw := net.Pipe()
+		clientRaw, serverRaw := gonet.Pipe()
 		defer clientRaw.Close()
 		defer serverRaw.Close()
 
-		clientConn, err := cfg.WrapConnClient(clientRaw)
+		clientConn, err := cfg.WrapConnClient(clientRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -738,10 +745,10 @@ func TestSudokuBDD(t *testing.T) {
 		countWireBytes := func(wrapServer func(net.Conn, *sudoku.Config) (net.Conn, error), cfg *sudoku.Config) int64 {
 			t.Helper()
 
-			clientRaw, serverRaw := net.Pipe()
+			clientRaw, serverRaw := gonet.Pipe()
 			watchedServerRaw := &countingConn{Conn: serverRaw}
 
-			clientConn, err := cfg.WrapConnClient(clientRaw)
+			clientConn, err := cfg.WrapConnClient(clientRaw, nil, nil)
 			if err != nil {
 				t.Fatal(err)
 			}
@@ -793,11 +800,11 @@ func TestSudokuBDD(t *testing.T) {
 			CustomTables: []string{"xpxvvpvv", "vxpvxvvp"},
 		}
 
-		clientRaw, serverRaw := net.Pipe()
+		clientRaw, serverRaw := gonet.Pipe()
 		defer clientRaw.Close()
 		defer serverRaw.Close()
 
-		clientConn, err := cfg.WrapConnClient(clientRaw)
+		clientConn, err := cfg.WrapConnClient(clientRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -835,11 +842,11 @@ func TestSudokuBDD(t *testing.T) {
 			PaddingMax:   0,
 		}
 
-		clientRaw, serverRaw := net.Pipe()
+		clientRaw, serverRaw := gonet.Pipe()
 		defer clientRaw.Close()
 		defer serverRaw.Close()
 
-		clientConn, err := cfg.WrapConnClient(clientRaw)
+		clientConn, err := cfg.WrapConnClient(clientRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -868,19 +875,6 @@ func TestSudokuBDD(t *testing.T) {
 		}
 	})
 
-	t.Run("GivenSudokuUDPMask_WhenNotInnermost_ThenWrapFails", func(t *testing.T) {
-		cfg := &sudoku.Config{Password: "sudoku-udp"}
-		raw, err := net.ListenPacket("udp", "127.0.0.1:0")
-		if err != nil {
-			t.Fatal(err)
-		}
-		defer raw.Close()
-
-		if _, err := cfg.WrapPacketConnClient(raw, 0, 1); err == nil {
-			t.Fatal("expected innermost check failure")
-		}
-	})
-
 	t.Run("GivenSudokuMultiTableUDPMask_WhenClientSendsMultipleDatagrams_ThenPayloadMatches", func(t *testing.T) {
 		cfg := &sudoku.Config{
 			Password:     "sudoku-udp-multi",
@@ -889,25 +883,24 @@ func TestSudokuBDD(t *testing.T) {
 			PaddingMin:   0,
 			PaddingMax:   0,
 		}
-		maskManager := finalmask.NewUdpmaskManager([]finalmask.Udpmask{cfg})
 
-		clientRaw, err := net.ListenPacket("udp", "127.0.0.1:0")
+		clientRaw, err := gonet.ListenPacket("udp", "127.0.0.1:0")
 		if err != nil {
 			t.Fatal(err)
 		}
 		defer clientRaw.Close()
 
-		serverRaw, err := net.ListenPacket("udp", "127.0.0.1:0")
+		serverRaw, err := gonet.ListenPacket("udp", "127.0.0.1:0")
 		if err != nil {
 			t.Fatal(err)
 		}
 		defer serverRaw.Close()
 
-		client, err := maskManager.WrapPacketConnClient(clientRaw)
+		client, err := cfg.WrapPacketConnClient(clientRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
-		server, err := maskManager.WrapPacketConnServer(serverRaw)
+		server, err := cfg.WrapPacketConnServer(serverRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -961,7 +954,7 @@ func TestSudokuBDD(t *testing.T) {
 		}
 		defer serverRaw.Close()
 
-		clientConn, err := cfg.WrapConnClient(clientRaw)
+		clientConn, err := cfg.WrapConnClient(clientRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -1008,11 +1001,11 @@ func TestSudokuBDD(t *testing.T) {
 			Ascii:    "prefer_entropy",
 		}
 
-		clientRaw, serverRaw := net.Pipe()
+		clientRaw, serverRaw := gonet.Pipe()
 		defer clientRaw.Close()
 		defer serverRaw.Close()
 
-		clientConn, err := cfg.WrapConnClient(clientRaw)
+		clientConn, err := cfg.WrapConnClient(clientRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -1032,11 +1025,11 @@ func TestSudokuBDD(t *testing.T) {
 			Ascii:    "prefer_entropy",
 		}
 
-		clientRaw, serverRaw := net.Pipe()
+		clientRaw, serverRaw := gonet.Pipe()
 		defer clientRaw.Close()
 		defer serverRaw.Close()
 
-		clientConn, err := cfg.WrapConnClient(clientRaw)
+		clientConn, err := cfg.WrapConnClient(clientRaw, nil, nil)
 		if err != nil {
 			t.Fatal(err)
 		}

transport/internet/finalmask/udphop/config.go

@@ -1,20 +1,17 @@
 package udphop
 
 import (
-	"net"
-
 	"github.com/xtls/xray-core/common/errors"
-	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	_, ok1 := raw.(*internet.FakePacketConn)
-	if level != 0 || ok1 {
-		return nil, errors.New("udphop requires being at the outermost level")
-	}
-	return NewUDPHopConn(c, raw)
+func (c *Config) HandleDial() {}
+
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewUDPHopConn(c, dest, dialer)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
 	return nil, errors.New("udphop: client only")
 }

transport/internet/finalmask/udphop/config.pb.go

@@ -7,7 +7,6 @@
 package udphop
 
 import (
-	internet "github.com/xtls/xray-core/transport/internet"
 	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
 	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
 	reflect "reflect"
@@ -24,14 +23,13 @@ const (
 
 type Config struct {
 	state         protoimpl.MessageState `protogen:"open.v1"`
-	Sockopt       *internet.SocketConfig `protobuf:"bytes,1,opt,name=sockopt,proto3" json:"sockopt,omitempty"`
 	Local         bool                   `protobuf:"varint,2,opt,name=local,proto3" json:"local,omitempty"`
 	Remote        bool                   `protobuf:"varint,3,opt,name=remote,proto3" json:"remote,omitempty"`
 	RemoteOnce    bool                   `protobuf:"varint,4,opt,name=remote_once,json=remoteOnce,proto3" json:"remote_once,omitempty"`
 	IntervalMin   int64                  `protobuf:"varint,5,opt,name=interval_min,json=intervalMin,proto3" json:"interval_min,omitempty"`
 	IntervalMax   int64                  `protobuf:"varint,6,opt,name=interval_max,json=intervalMax,proto3" json:"interval_max,omitempty"`
-	RemotePorts   []uint32               `protobuf:"varint,7,rep,packed,name=remote_ports,json=remotePorts,proto3" json:"remote_ports,omitempty"`
-	RemoteIPs     []string               `protobuf:"bytes,8,rep,name=remoteIPs,proto3" json:"remoteIPs,omitempty"`
+	RemoteIPs     []string               `protobuf:"bytes,7,rep,name=remoteIPs,proto3" json:"remoteIPs,omitempty"`
+	RemotePorts   []uint32               `protobuf:"varint,8,rep,packed,name=remote_ports,json=remotePorts,proto3" json:"remote_ports,omitempty"`
 	unknownFields protoimpl.UnknownFields
 	sizeCache     protoimpl.SizeCache
 }
@@ -66,13 +64,6 @@ func (*Config) Descriptor() ([]byte, []int) {
 	return file_transport_internet_finalmask_udphop_config_proto_rawDescGZIP(), []int{0}
 }
 
-func (x *Config) GetSockopt() *internet.SocketConfig {
-	if x != nil {
-		return x.Sockopt
-	}
-	return nil
-}
-
 func (x *Config) GetLocal() bool {
 	if x != nil {
 		return x.Local
@@ -108,16 +99,16 @@ func (x *Config) GetIntervalMax() int64 {
 	return 0
 }
 
-func (x *Config) GetRemotePorts() []uint32 {
+func (x *Config) GetRemoteIPs() []string {
 	if x != nil {
-		return x.RemotePorts
+		return x.RemoteIPs
 	}
 	return nil
 }
 
-func (x *Config) GetRemoteIPs() []string {
+func (x *Config) GetRemotePorts() []uint32 {
 	if x != nil {
-		return x.RemoteIPs
+		return x.RemotePorts
 	}
 	return nil
 }
@@ -126,17 +117,16 @@ var File_transport_internet_finalmask_udphop_config_proto protoreflect.FileDescr
 
 const file_transport_internet_finalmask_udphop_config_proto_rawDesc = "" +
 	"\n" +
-	"0transport/internet/finalmask/udphop/config.proto\x12(xray.transport.internet.finalmask.udphop\x1a\x1ftransport/internet/config.proto\"\x9f\x02\n" +
-	"\x06Config\x12?\n" +
-	"\asockopt\x18\x01 \x01(\v2%.xray.transport.internet.SocketConfigR\asockopt\x12\x14\n" +
+	"0transport/internet/finalmask/udphop/config.proto\x12(xray.transport.internet.finalmask.udphop\"\xe4\x01\n" +
+	"\x06Config\x12\x14\n" +
 	"\x05local\x18\x02 \x01(\bR\x05local\x12\x16\n" +
 	"\x06remote\x18\x03 \x01(\bR\x06remote\x12\x1f\n" +
 	"\vremote_once\x18\x04 \x01(\bR\n" +
 	"remoteOnce\x12!\n" +
 	"\finterval_min\x18\x05 \x01(\x03R\vintervalMin\x12!\n" +
-	"\finterval_max\x18\x06 \x01(\x03R\vintervalMax\x12!\n" +
-	"\fremote_ports\x18\a \x03(\rR\vremotePorts\x12\x1c\n" +
-	"\tremoteIPs\x18\b \x03(\tR\tremoteIPsB\x9a\x01\n" +
+	"\finterval_max\x18\x06 \x01(\x03R\vintervalMax\x12\x1c\n" +
+	"\tremoteIPs\x18\a \x03(\tR\tremoteIPs\x12!\n" +
+	"\fremote_ports\x18\b \x03(\rR\vremotePortsJ\x04\b\x01\x10\x02B\x9a\x01\n" +
 	",com.xray.transport.internet.finalmask.udphopP\x01Z=github.com/xtls/xray-core/transport/internet/finalmask/udphop\xaa\x02(Xray.Transport.Internet.Finalmask.Udphopb\x06proto3"
 
 var (
@@ -153,16 +143,14 @@ func file_transport_internet_finalmask_udphop_config_proto_rawDescGZIP() []byte
 
 var file_transport_internet_finalmask_udphop_config_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
 var file_transport_internet_finalmask_udphop_config_proto_goTypes = []any{
-	(*Config)(nil),                // 0: xray.transport.internet.finalmask.udphop.Config
-	(*internet.SocketConfig)(nil), // 1: xray.transport.internet.SocketConfig
+	(*Config)(nil), // 0: xray.transport.internet.finalmask.udphop.Config
 }
 var file_transport_internet_finalmask_udphop_config_proto_depIdxs = []int32{
-	1, // 0: xray.transport.internet.finalmask.udphop.Config.sockopt:type_name -> xray.transport.internet.SocketConfig
-	1, // [1:1] is the sub-list for method output_type
-	1, // [1:1] is the sub-list for method input_type
-	1, // [1:1] is the sub-list for extension type_name
-	1, // [1:1] is the sub-list for extension extendee
-	0, // [0:1] is the sub-list for field type_name
+	0, // [0:0] is the sub-list for method output_type
+	0, // [0:0] is the sub-list for method input_type
+	0, // [0:0] is the sub-list for extension type_name
+	0, // [0:0] is the sub-list for extension extendee
+	0, // [0:0] is the sub-list for field type_name
 }
 
 func init() { file_transport_internet_finalmask_udphop_config_proto_init() }

transport/internet/finalmask/udphop/config.proto

@@ -6,16 +6,14 @@ option go_package = "github.com/xtls/xray-core/transport/internet/finalmask/udph
 option java_package = "com.xray.transport.internet.finalmask.udphop";
 option java_multiple_files = true;
 
-import "transport/internet/config.proto";
-
 message Config {
-  xray.transport.internet.SocketConfig sockopt = 1;
+  reserved 1;
   bool local = 2;
   bool remote = 3;
   bool remote_once = 4;
   int64 interval_min = 5;
   int64 interval_max = 6;
-  repeated uint32 remote_ports = 7;
-  repeated string remoteIPs = 8;
+  repeated string remoteIPs = 7;
+  repeated uint32 remote_ports = 8;
 }
 

transport/internet/finalmask/udphop/conn.go

@@ -6,9 +6,7 @@ import (
 	goerrors "errors"
 	"io"
 	mrand "math/rand"
-	gonet "net"
 	"net/netip"
-	"reflect"
 	"sync"
 	"time"
 
@@ -16,8 +14,6 @@ import (
 	"github.com/xtls/xray-core/common/crypto"
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/net"
-	"github.com/xtls/xray-core/common/net/cnc"
-	"github.com/xtls/xray-core/transport/internet"
 	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
@@ -34,16 +30,14 @@ type packet struct {
 }
 
 type udpHopConn struct {
-	conn       net.PacketConn
-	sockopt    *internet.SocketConfig
-	local      bool
-	remote     bool
-	remoteOnce bool
+	dialer *finalmask.Dialer
+	local  bool
+	remote bool
 
 	intervalMin int64
 	intervalMax int64
-	remotePorts []uint32
 	remoteIPs   []netip.Prefix
+	remotePorts []uint32
 
 	deadline      time.Time
 	readDeadline  time.Time
@@ -55,10 +49,10 @@ type udpHopConn struct {
 	readCh  chan packet
 	closeCh chan struct{}
 	wg      sync.WaitGroup
-	mu      sync.Mutex
+	mu      sync.RWMutex
 }
 
-func NewUDPHopConn(c *Config, raw net.PacketConn) (net.PacketConn, error) {
+func NewUDPHopConn(c *Config, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
 	if c.IntervalMin < 5 || c.IntervalMax < 5 {
 		return nil, errors.New("invalid interval")
 	}
@@ -66,22 +60,40 @@ func NewUDPHopConn(c *Config, raw net.PacketConn) (net.PacketConn, error) {
 	for _, ip := range c.RemoteIPs {
 		remoteIPs = append(remoteIPs, netip.MustParsePrefix(ip))
 	}
-	conn := &udpHopConn{
-		conn:       raw,
-		sockopt:    c.Sockopt,
-		local:      c.Local,
-		remote:     c.Remote,
-		remoteOnce: c.RemoteOnce,
+	remotePorts := c.RemotePorts
+	if c.Remote || c.RemoteOnce {
+		if len(remoteIPs) > 0 {
+			dest.Address = net.IPAddress(randPrefix(remoteIPs[mrand.Intn(len(remoteIPs))]))
+		}
+		if len(remotePorts) > 0 {
+			dest.Port = net.Port(remotePorts[mrand.Intn(len(remotePorts))])
+		}
+	}
+	conn, err := dialer.DialUDP(*dest)
+	if err != nil {
+		return nil, err
+	}
+	cur := conn.(*finalmask.PacketConnWrapper).PacketConn
+	addr := conn.RemoteAddr().(*net.UDPAddr)
+	client := &udpHopConn{
+		dialer: dialer,
+		local:  c.Local,
+		remote: c.Remote,
 
 		intervalMin: c.IntervalMin,
 		intervalMax: c.IntervalMax,
-		remotePorts: c.RemotePorts,
 		remoteIPs:   remoteIPs,
+		remotePorts: remotePorts,
 
+		cur:     cur,
+		addr:    addr,
 		readCh:  make(chan packet),
 		closeCh: make(chan struct{}),
 	}
-	return conn, nil
+	go client.run()
+	client.wg.Add(1)
+	go client.recv(client.cur)
+	return client, nil
 }
 
 func (c *udpHopConn) closed() bool {
@@ -93,61 +105,67 @@ func (c *udpHopConn) closed() bool {
 	}
 }
 
-func (c *udpHopConn) hop(addr *net.UDPAddr) {
+func (c *udpHopConn) run() {
+	ticker := time.NewTicker(time.Second * time.Duration(crypto.RandBetween(c.intervalMin, c.intervalMax+1)))
+	defer ticker.Stop()
+	for {
+		select {
+		case <-c.closeCh:
+			return
+		case <-ticker.C:
+			ticker.Reset(time.Second * time.Duration(crypto.RandBetween(c.intervalMin, c.intervalMax+1)))
+			c.hop()
+		}
+	}
+}
+
+func (c *udpHopConn) hop() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	if c.closed() {
 		return
 	}
-	newAddr := &net.UDPAddr{IP: addr.IP, Port: addr.Port}
-	newConn := c.conn
-	if c.remote || c.remoteOnce && c.addr == nil {
-		if len(c.remotePorts) > 0 {
-			newAddr.Port = int(c.remotePorts[mrand.Intn(len(c.remotePorts))])
-		}
+	oldIP := c.addr.IP
+	oldPort := c.addr.Port
+	if c.remote {
 		if len(c.remoteIPs) > 0 {
-			newAddr.IP = randPrefix(c.remoteIPs[mrand.Intn(len(c.remoteIPs))])
+			c.addr.IP = randPrefix(c.remoteIPs[mrand.Intn(len(c.remoteIPs))])
+		}
+		if len(c.remotePorts) > 0 {
+			c.addr.Port = int(c.remotePorts[mrand.Intn(len(c.remotePorts))])
 		}
 	}
 	if c.local {
-		raw, err := internet.DialSystem(context.Background(), net.UDPDestination(net.IPAddress(newAddr.IP), net.Port(newAddr.Port)), c.sockopt)
+		conn, err := c.dialer.DialUDP(net.UDPDestination(net.IPAddress(c.addr.IP), net.Port(c.addr.Port)))
 		if err != nil {
+			c.addr.IP = oldIP
+			c.addr.Port = oldPort
 			errors.LogErrorInner(context.Background(), err, "hop err")
 			return
 		}
-		switch c := raw.(type) {
-		case *internet.PacketConnWrapper:
-			newConn = c.PacketConn
-		case *cnc.Connection:
-			newConn = &internet.FakePacketConn{Conn: c}
-		default:
-			panic(reflect.TypeOf(c))
-		}
-		newConn.SetDeadline(c.deadline)
-		newConn.SetReadDeadline(c.readDeadline)
-		newConn.SetWriteDeadline(c.writeDeadline)
+		conn.SetDeadline(c.deadline)
+		conn.SetReadDeadline(c.readDeadline)
+		conn.SetWriteDeadline(c.writeDeadline)
 		if c.pre != nil {
 			_ = c.pre.Close()
 		}
 		c.pre = c.cur
+		c.cur = conn.(*finalmask.PacketConnWrapper).PacketConn
 		c.wg.Add(1)
-		go c.recv(newConn)
+		go c.recv(c.cur)
 	}
-	c.addr = newAddr
-	c.cur = newConn
 }
 
 func (c *udpHopConn) recv(conn net.PacketConn) {
 	defer c.wg.Done()
 
 	for {
-		if c.closed() {
-			return
-		}
 		p := pool.Get().([]byte)
 		n, addr, err := conn.ReadFrom(p)
 		if err != nil {
 			pool.Put(p[:cap(p)])
-			if goerrors.Is(err, io.EOF) || goerrors.Is(err, io.ErrClosedPipe) || goerrors.Is(err, gonet.ErrClosed) {
-				break
+			if c.closed() {
+				return
 			}
 			var netErr net.Error
 			if goerrors.As(err, &netErr) && netErr.Timeout() {
@@ -156,9 +174,10 @@ func (c *udpHopConn) recv(conn net.PacketConn) {
 				case <-c.closeCh:
 					return
 				}
+				continue
 			}
 			errors.LogErrorInner(context.Background(), err, "recv err")
-			continue
+			return
 		}
 		select {
 		case c.readCh <- packet{p: p[:n], addr: addr}:
@@ -169,22 +188,6 @@ func (c *udpHopConn) recv(conn net.PacketConn) {
 	}
 }
 
-func (c *udpHopConn) hopLoop() {
-	ticker := time.NewTicker(time.Second * time.Duration(crypto.RandBetween(c.intervalMin, c.intervalMax+1)))
-	defer ticker.Stop()
-	for {
-		select {
-		case <-ticker.C:
-			ticker.Reset(time.Second * time.Duration(crypto.RandBetween(c.intervalMin, c.intervalMax+1)))
-			c.mu.Lock()
-			c.hop(c.addr)
-			c.mu.Unlock()
-		case <-c.closeCh:
-			return
-		}
-	}
-}
-
 func (c *udpHopConn) ReadFrom(p []byte) (n int, addr net.Addr, err error) {
 	packet, ok := <-c.readCh
 	if ok {
@@ -194,21 +197,12 @@ func (c *udpHopConn) ReadFrom(p []byte) (n int, addr net.Addr, err error) {
 		}
 		return n, packet.addr, packet.err
 	}
-	return 0, nil, io.EOF
+	return 0, nil, io.ErrClosedPipe
 }
 
 func (c *udpHopConn) WriteTo(p []byte, addr net.Addr) (n int, err error) {
-	c.mu.Lock()
-	defer c.mu.Unlock()
-
-	if c.cur == nil {
-		c.hop(addr.(*net.UDPAddr))
-		if c.cur == nil {
-			return 0, nil
-		}
-		go c.hopLoop()
-	}
-
+	c.mu.RLock()
+	defer c.mu.RUnlock()
 	_, err = c.cur.WriteTo(p, c.addr)
 	if err != nil {
 		errors.LogErrorInner(context.Background(), err, "send err")
@@ -227,15 +221,12 @@ func (c *udpHopConn) Close() error {
 	if c.pre != nil {
 		_ = c.pre.Close()
 	}
-	if c.cur != nil {
-		_ = c.cur.Close()
-	}
-	_ = c.conn.Close()
+	_ = c.cur.Close()
 	c.wg.Wait()
 	select {
-	case p := <-c.readCh:
-		if p.p != nil {
-			pool.Put(p.p[:cap(p.p)])
+	case packet := <-c.readCh:
+		if packet.p != nil {
+			pool.Put(packet.p[:cap(packet.p)])
 		}
 	default:
 	}
@@ -244,7 +235,9 @@ func (c *udpHopConn) Close() error {
 }
 
 func (c *udpHopConn) LocalAddr() net.Addr {
-	return c.conn.LocalAddr()
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.cur.LocalAddr()
 }
 
 func (c *udpHopConn) SetDeadline(t time.Time) error {
@@ -254,10 +247,7 @@ func (c *udpHopConn) SetDeadline(t time.Time) error {
 	if c.pre != nil {
 		_ = c.pre.SetDeadline(t)
 	}
-	if c.cur != nil {
-		_ = c.cur.SetDeadline(t)
-	}
-	return nil
+	return c.cur.SetDeadline(t)
 }
 
 func (c *udpHopConn) SetReadDeadline(t time.Time) error {
@@ -267,10 +257,7 @@ func (c *udpHopConn) SetReadDeadline(t time.Time) error {
 	if c.pre != nil {
 		_ = c.pre.SetReadDeadline(t)
 	}
-	if c.cur != nil {
-		_ = c.cur.SetReadDeadline(t)
-	}
-	return nil
+	return c.cur.SetReadDeadline(t)
 }
 
 func (c *udpHopConn) SetWriteDeadline(t time.Time) error {
@@ -280,10 +267,7 @@ func (c *udpHopConn) SetWriteDeadline(t time.Time) error {
 	if c.pre != nil {
 		_ = c.pre.SetWriteDeadline(t)
 	}
-	if c.cur != nil {
-		_ = c.cur.SetWriteDeadline(t)
-	}
-	return nil
+	return c.cur.SetWriteDeadline(t)
 }
 
 func randPrefix(p netip.Prefix) []byte {

transport/internet/finalmask/xdns/config.go

@@ -1,21 +1,14 @@
 package xdns
 
 import (
-	"net"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	// _, ok1 := raw.(*internet.FakePacketConn)
-	// _, ok2 := raw.(*udphop.UdpHopPacketConn)
-	// if level != 0 || ok1 || ok2 {
-	// 	return nil, errors.New("xdns requires being at the outermost level")
-	// }
-	return NewConnClient(c, raw)
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return NewConnClient(c, conn)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	// if level != 0 {
-	// 	return nil, errors.New("xdns requires being at the outermost level")
-	// }
-	return NewConnServer(c, raw)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServer(c, conn)
 }

transport/internet/finalmask/xicmp/client.go

@@ -8,8 +8,7 @@ import (
 	goerrors "errors"
 	"fmt"
 	"io"
-	mathrand "math/rand"
-	"net"
+	mrand "math/rand"
 	"net/netip"
 	"sync"
 	"time"
@@ -17,6 +16,7 @@ import (
 
 	"github.com/xtls/xray-core/common"
 	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/transport/internet/finalmask"
 	"golang.org/x/net/icmp"
 	"golang.org/x/net/ipv4"
@@ -36,11 +36,11 @@ type packet struct {
 }
 
 type xicmpConnClient struct {
-	conn     net.PacketConn
 	icmp4    *icmp.PacketConn
 	icmp6    *icmp.PacketConn
 	udp      bool
 	ips      []netip.Addr
+	ip       net.IP
 	clientID [8]byte
 	id       int
 	seq      int
@@ -50,7 +50,7 @@ type xicmpConnClient struct {
 	mu       sync.Mutex
 }
 
-func NewConnClient(c *Config, raw net.PacketConn) (net.PacketConn, error) {
+func NewConnClient(c *Config, dest *net.Destination) (net.PacketConn, error) {
 	var icmp4, icmp6 *icmp.PacketConn
 	var err4, err6 error
 	if c.DGRAM {
@@ -69,17 +69,24 @@ func NewConnClient(c *Config, raw net.PacketConn) (net.PacketConn, error) {
 		ips = append(ips, netip.MustParseAddr(ip))
 	}
 
+	var ip net.IP
+	if len(ips) > 0 {
+		ip = ips[mrand.Intn(len(ips))].AsSlice()
+	} else {
+		ip = dest.Address.IP()
+	}
+
 	var clientID [8]byte
 	common.Must2(rand.Read(clientID[:]))
 
 	conn := &xicmpConnClient{
-		conn:     raw,
 		icmp4:    icmp4,
 		icmp6:    icmp6,
 		udp:      c.DGRAM,
 		ips:      ips,
+		ip:       ip,
 		clientID: clientID,
-		id:       mathrand.Intn(65536),
+		id:       mrand.Intn(65536),
 		seq:      1,
 		readCh:   make(chan packet),
 		closeCh:  make(chan struct{}),
@@ -92,10 +99,6 @@ func NewConnClient(c *Config, raw net.PacketConn) (net.PacketConn, error) {
 	return conn, nil
 }
 
-func (c *xicmpConnClient) ring(a, b uint16) uint16 {
-	return min(a-b, b-a)
-}
-
 func (c *xicmpConnClient) closed() bool {
 	select {
 	case <-c.closeCh:
@@ -110,12 +113,11 @@ func (c *xicmpConnClient) recv4() {
 
 	var b [finalmask.UDPSize]byte
 	for {
-		if c.closed() {
-			return
-		}
-
 		n, addr, err := c.icmp4.ReadFrom(b[:])
 		if err != nil {
+			if c.closed() {
+				return
+			}
 			var netErr net.Error
 			if goerrors.As(err, &netErr) && netErr.Timeout() {
 				select {
@@ -125,9 +127,10 @@ func (c *xicmpConnClient) recv4() {
 				case <-c.closeCh:
 					return
 				}
+				continue
 			}
-			errors.LogErrorInner(context.Background(), err, "recv4 err")
-			continue
+			errors.LogErrorInner(context.Background(), err, "recv err 4")
+			return
 		}
 
 		msg, err := icmp.ParseMessage(1, b[:n])
@@ -150,10 +153,6 @@ func (c *xicmpConnClient) recv4() {
 			continue
 		}
 
-		if c.ring(uint16(echo.Seq), uint16(c.seq)) > 1000 {
-			continue
-		}
-
 		if len(echo.Data) > 8 && bytes.Equal(echo.Data[:8], c.clientID[:]) {
 			continue
 		}
@@ -182,12 +181,11 @@ func (c *xicmpConnClient) recv6() {
 
 	var b [finalmask.UDPSize]byte
 	for {
-		if c.closed() {
-			return
-		}
-
 		n, addr, err := c.icmp6.ReadFrom(b[:])
 		if err != nil {
+			if c.closed() {
+				return
+			}
 			var netErr net.Error
 			if goerrors.As(err, &netErr) && netErr.Timeout() {
 				select {
@@ -197,9 +195,10 @@ func (c *xicmpConnClient) recv6() {
 				case <-c.closeCh:
 					return
 				}
+				continue
 			}
-			errors.LogErrorInner(context.Background(), err, "recv6 err")
-			continue
+			errors.LogErrorInner(context.Background(), err, "recv err 6")
+			return
 		}
 
 		msg, err := icmp.ParseMessage(58, b[:n])
@@ -222,10 +221,6 @@ func (c *xicmpConnClient) recv6() {
 			continue
 		}
 
-		if c.ring(uint16(echo.Seq), uint16(c.seq)) > 1000 {
-			continue
-		}
-
 		if len(echo.Data) > 8 && bytes.Equal(echo.Data[:8], c.clientID[:]) {
 			continue
 		}
@@ -273,9 +268,9 @@ func (c *xicmpConnClient) WriteTo(p []byte, addr net.Addr) (n int, err error) {
 	c.seq %= 65536
 	c.mu.Unlock()
 
-	ip := addr.(*net.UDPAddr).IP
+	ip := c.ip
 	if len(c.ips) > 0 {
-		ip = c.ips[mathrand.Intn(len(c.ips))].AsSlice()
+		ip = c.ips[mrand.Intn(len(c.ips))].AsSlice()
 	}
 
 	if c.udp {
@@ -314,7 +309,6 @@ func (c *xicmpConnClient) Close() error {
 	close(c.closeCh)
 	_ = c.icmp4.Close()
 	_ = c.icmp6.Close()
-	_ = c.conn.Close()
 	c.wg.Wait()
 	select {
 	case p := <-c.readCh:
@@ -328,7 +322,7 @@ func (c *xicmpConnClient) Close() error {
 }
 
 func (c *xicmpConnClient) LocalAddr() net.Addr {
-	return c.conn.LocalAddr()
+	return &net.UDPAddr{IP: []byte{0, 0, 0, 0}}
 }
 
 func (c *xicmpConnClient) SetDeadline(t time.Time) error {

transport/internet/finalmask/xicmp/config.go

@@ -1,23 +1,23 @@
 package xicmp
 
 import (
-	"net"
+	"errors"
 
-	"github.com/xtls/xray-core/common/errors"
-	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
-func (c *Config) WrapPacketConnClient(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	_, ok1 := raw.(*internet.FakePacketConn)
-	if level != 0 || ok1 {
-		return nil, errors.New("xicmp requires being at the outermost level")
+func (c *Config) HandleDial() {}
+
+func (c *Config) HandleListen() {}
+
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	if dest.Address.Family().IsDomain() && len(c.IPs) == 0 {
+		return nil, errors.New("empty ip addresses")
 	}
-	return NewConnClient(c, raw)
+	return NewConnClient(c, dest)
 }
 
-func (c *Config) WrapPacketConnServer(raw net.PacketConn, level int, levelCount int) (net.PacketConn, error) {
-	if level != 0 {
-		return nil, errors.New("xicmp requires being at the outermost level")
-	}
-	return NewConnServer(c, raw)
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	return NewConnServer(c)
 }

transport/internet/finalmask/xicmp/server.go

@@ -37,7 +37,6 @@ type record struct {
 }
 
 type xicmpConnServer struct {
-	conn    net.PacketConn
 	icmp4   *icmp.PacketConn
 	icmp6   *icmp.PacketConn
 	ips     map[netip.Addr]struct{}
@@ -48,7 +47,7 @@ type xicmpConnServer struct {
 	mu      sync.Mutex
 }
 
-func NewConnServer(c *Config, raw net.PacketConn) (net.PacketConn, error) {
+func NewConnServer(c *Config) (net.PacketConn, error) {
 	icmp4, err := icmp.ListenPacket("ip4:icmp", "0.0.0.0")
 	if err != nil {
 		return nil, err
@@ -64,7 +63,6 @@ func NewConnServer(c *Config, raw net.PacketConn) (net.PacketConn, error) {
 	}
 
 	conn := &xicmpConnServer{
-		conn:    raw,
 		icmp4:   icmp4,
 		icmp6:   icmp6,
 		ips:     ips,
@@ -115,12 +113,11 @@ func (c *xicmpConnServer) recv4() {
 
 	var b [finalmask.UDPSize]byte
 	for {
-		if c.closed() {
-			return
-		}
-
 		n, addr, err := c.icmp4.ReadFrom(b[:])
 		if err != nil {
+			if c.closed() {
+				return
+			}
 			var netErr net.Error
 			if goerrors.As(err, &netErr) && netErr.Timeout() {
 				select {
@@ -130,9 +127,10 @@ func (c *xicmpConnServer) recv4() {
 				case <-c.closeCh:
 					return
 				}
+				continue
 			}
-			errors.LogErrorInner(context.Background(), err, "recv4 err")
-			continue
+			errors.LogErrorInner(context.Background(), err, "recv err 4")
+			return
 		}
 
 		msg, err := icmp.ParseMessage(1, b[:n])
@@ -195,12 +193,11 @@ func (c *xicmpConnServer) recv6() {
 
 	var b [finalmask.UDPSize]byte
 	for {
-		if c.closed() {
-			return
-		}
-
 		n, addr, err := c.icmp6.ReadFrom(b[:])
 		if err != nil {
+			if c.closed() {
+				return
+			}
 			var netErr net.Error
 			if goerrors.As(err, &netErr) && netErr.Timeout() {
 				select {
@@ -210,9 +207,10 @@ func (c *xicmpConnServer) recv6() {
 				case <-c.closeCh:
 					return
 				}
+				continue
 			}
-			errors.LogErrorInner(context.Background(), err, "recv6 err")
-			continue
+			errors.LogErrorInner(context.Background(), err, "recv err 6")
+			return
 		}
 
 		msg, err := icmp.ParseMessage(58, b[:n])
@@ -330,7 +328,6 @@ func (c *xicmpConnServer) Close() error {
 	close(c.closeCh)
 	_ = c.icmp4.Close()
 	_ = c.icmp6.Close()
-	_ = c.conn.Close()
 	c.wg.Wait()
 	select {
 	case p := <-c.readCh:
@@ -344,7 +341,7 @@ func (c *xicmpConnServer) Close() error {
 }
 
 func (c *xicmpConnServer) LocalAddr() net.Addr {
-	return c.conn.LocalAddr()
+	return &net.UDPAddr{IP: []byte{0, 0, 0, 0}}
 }
 
 func (c *xicmpConnServer) SetDeadline(t time.Time) error {

transport/internet/finalmask/xicmp/server_oob.go

@@ -39,7 +39,6 @@ type record struct {
 }
 
 type xicmpConnServer struct {
-	conn    net.PacketConn
 	icmp4   *icmp.PacketConn
 	icmp6   *icmp.PacketConn
 	ipv4PC  *ipv4.PacketConn
@@ -52,7 +51,7 @@ type xicmpConnServer struct {
 	mu      sync.Mutex
 }
 
-func NewConnServer(c *Config, raw net.PacketConn) (net.PacketConn, error) {
+func NewConnServer(c *Config) (net.PacketConn, error) {
 	icmp4, err := icmp.ListenPacket("ip4:icmp", "0.0.0.0")
 	if err != nil {
 		return nil, err
@@ -68,7 +67,6 @@ func NewConnServer(c *Config, raw net.PacketConn) (net.PacketConn, error) {
 	}
 
 	conn := &xicmpConnServer{
-		conn:    raw,
 		icmp4:   icmp4,
 		icmp6:   icmp6,
 		ipv4PC:  icmp4.IPv4PacketConn(),
@@ -124,12 +122,11 @@ func (c *xicmpConnServer) recv4() {
 
 	var b [finalmask.UDPSize]byte
 	for {
-		if c.closed() {
-			return
-		}
-
 		n, cm, addr, err := c.ipv4PC.ReadFrom(b[:])
 		if err != nil {
+			if c.closed() {
+				return
+			}
 			var netErr net.Error
 			if goerrors.As(err, &netErr) && netErr.Timeout() {
 				select {
@@ -139,9 +136,10 @@ func (c *xicmpConnServer) recv4() {
 				case <-c.closeCh:
 					return
 				}
+				continue
 			}
-			errors.LogErrorInner(context.Background(), err, "recv4 err")
-			continue
+			errors.LogErrorInner(context.Background(), err, "recv err 4")
+			return
 		}
 
 		msg, err := icmp.ParseMessage(1, b[:n])
@@ -205,12 +203,11 @@ func (c *xicmpConnServer) recv6() {
 
 	var b [finalmask.UDPSize]byte
 	for {
-		if c.closed() {
-			return
-		}
-
 		n, cm, addr, err := c.ipv6PC.ReadFrom(b[:])
 		if err != nil {
+			if c.closed() {
+				return
+			}
 			var netErr net.Error
 			if goerrors.As(err, &netErr) && netErr.Timeout() {
 				select {
@@ -220,9 +217,10 @@ func (c *xicmpConnServer) recv6() {
 				case <-c.closeCh:
 					return
 				}
+				continue
 			}
-			errors.LogErrorInner(context.Background(), err, "recv6 err")
-			continue
+			errors.LogErrorInner(context.Background(), err, "recv err 6")
+			return
 		}
 
 		msg, err := icmp.ParseMessage(58, b[:n])
@@ -341,7 +339,6 @@ func (c *xicmpConnServer) Close() error {
 	close(c.closeCh)
 	_ = c.icmp4.Close()
 	_ = c.icmp6.Close()
-	_ = c.conn.Close()
 	c.wg.Wait()
 	select {
 	case p := <-c.readCh:
@@ -355,7 +352,7 @@ func (c *xicmpConnServer) Close() error {
 }
 
 func (c *xicmpConnServer) LocalAddr() net.Addr {
-	return c.conn.LocalAddr()
+	return &net.UDPAddr{IP: []byte{0, 0, 0, 0}}
 }
 
 func (c *xicmpConnServer) SetDeadline(t time.Time) error {

transport/internet/finalmask/xmc/config.go

@@ -2,10 +2,12 @@ package xmc
 
 import (
 	"fmt"
-	"net"
+
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
-func (c *Config) WrapConnClient(conn net.Conn) (net.Conn, error) {
+func (c *Config) WrapConnClient(conn net.Conn, dest *net.Destination, dialer *finalmask.Dialer) (net.Conn, error) {
 	profiles, err := profilesFromConfig(c.Profiles)
 	if err != nil {
 		return nil, fmt.Errorf("minecraft finalmask: %w", err)

transport/internet/grpc/dial.go

@@ -83,7 +83,6 @@ func getGrpcClient(ctx context.Context, dest net.Destination, streamSettings *in
 	}
 	tlsConfig := tls.ConfigFromStreamSettings(streamSettings)
 	realityConfig := reality.ConfigFromStreamSettings(streamSettings)
-	sockopt := streamSettings.SocketSettings
 	grpcSettings := streamSettings.ProtocolSettings.(*Config)
 
 	if client, found := globalDialerMap[dialerConf{dest, streamSettings}]; found && client.GetState() != connectivity.Shutdown {
@@ -124,17 +123,13 @@ func getGrpcClient(ctx context.Context, dest net.Destination, streamSettings *in
 			gctx = session.ContextWithOutbounds(gctx, session.OutboundsFromContext(ctx))
 			gctx = session.ContextWithTimeoutOnly(gctx, true)
 
-			c, err := internet.DialSystem(gctx, net.TCPDestination(address, port), sockopt)
+			var c net.Conn
+			if streamSettings.FinalMask != nil {
+				c, err = streamSettings.FinalMask.DialTCP(gctx, net.TCPDestination(address, port))
+			} else {
+				c, err = internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
+			}
 			if err == nil {
-				if streamSettings.TcpmaskManager != nil {
-					newConn, err := streamSettings.TcpmaskManager.WrapConnClient(c)
-					if err != nil {
-						c.Close()
-						return nil, errors.New("mask err").Base(err)
-					}
-					c = newConn
-				}
-
 				if tlsConfig != nil {
 					config := tlsConfig.GetTLSConfig(tls.WithDestination(dest))
 					if fingerprint := tls.GetFingerprint(tlsConfig.Fingerprint); fingerprint != nil {

transport/internet/grpc/hub.go

@@ -104,28 +104,20 @@ func Listen(ctx context.Context, address net.Address, port net.Port, settings *i
 	go func() {
 		var streamListener net.Listener
 		var err error
+		var addr net.Addr
 		if port == net.Port(0) { // unix
-			streamListener, err = internet.ListenSystem(ctx, &net.UnixAddr{
-				Name: address.Domain(),
-				Net:  "unix",
-			}, settings.SocketSettings)
-			if err != nil {
-				errors.LogErrorInner(ctx, err, "failed to listen on ", address)
-				return
-			}
+			addr = &net.UnixAddr{Name: address.Domain(), Net: "unix"}
 		} else { // tcp
-			streamListener, err = internet.ListenSystem(ctx, &net.TCPAddr{
-				IP:   address.IP(),
-				Port: int(port),
-			}, settings.SocketSettings)
-			if err != nil {
-				errors.LogErrorInner(ctx, err, "failed to listen on ", address, ":", port)
-				return
-			}
+			addr = &net.TCPAddr{IP: address.IP(), Port: int(port)}
 		}
-
-		if settings.TcpmaskManager != nil {
-			streamListener, _ = settings.TcpmaskManager.WrapListener(streamListener)
+		if settings.FinalMask != nil {
+			streamListener, err = settings.FinalMask.Listen(ctx, addr)
+		} else {
+			streamListener, err = internet.ListenSystem(ctx, addr, settings.SocketSettings)
+		}
+		if err != nil {
+			errors.LogErrorInner(ctx, err, "failed to listen on ", address, ":", port)
+			return
 		}
 
 		errors.LogDebug(ctx, "gRPC listen for service name `"+grpcSettings.getServiceName()+"` tun `"+grpcSettings.getTunStreamName()+"` multi tun `"+grpcSettings.getTunMultiStreamName()+"`")

transport/internet/httpupgrade/dialer.go

@@ -46,21 +46,18 @@ func (c *ConnRF) Read(b []byte) (int, error) {
 func dialhttpUpgrade(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (net.Conn, error) {
 	transportConfiguration := streamSettings.ProtocolSettings.(*Config)
 
-	pconn, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
+	var pconn net.Conn
+	var err error
+	if streamSettings.FinalMask != nil {
+		pconn, err = streamSettings.FinalMask.DialTCP(ctx, dest)
+	} else {
+		pconn, err = internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
+	}
 	if err != nil {
 		errors.LogErrorInner(ctx, err, "failed to dial to ", dest)
 		return nil, err
 	}
 
-	if streamSettings.TcpmaskManager != nil {
-		newConn, err := streamSettings.TcpmaskManager.WrapConnClient(pconn)
-		if err != nil {
-			pconn.Close()
-			return nil, errors.New("mask err").Base(err)
-		}
-		pconn = newConn
-	}
-
 	var conn net.Conn
 	var requestURL url.URL
 	tConfig := tls.ConfigFromStreamSettings(streamSettings)

transport/internet/httpupgrade/hub.go

@@ -124,29 +124,21 @@ func ListenHTTPUpgrade(ctx context.Context, address net.Address, port net.Port,
 	}
 	var listener net.Listener
 	var err error
+	var addr net.Addr
 	if port == net.Port(0) { // unix
-		listener, err = internet.ListenSystem(ctx, &net.UnixAddr{
-			Name: address.Domain(),
-			Net:  "unix",
-		}, streamSettings.SocketSettings)
-		if err != nil {
-			return nil, errors.New("failed to listen unix domain socket(for HttpUpgrade) on ", address).Base(err)
-		}
-		errors.LogInfo(ctx, "listening unix domain socket(for HttpUpgrade) on ", address)
+		addr = &net.UnixAddr{Name: address.Domain(), Net: "unix"}
 	} else { // tcp
-		listener, err = internet.ListenSystem(ctx, &net.TCPAddr{
-			IP:   address.IP(),
-			Port: int(port),
-		}, streamSettings.SocketSettings)
-		if err != nil {
-			return nil, errors.New("failed to listen TCP(for HttpUpgrade) on ", address, ":", port).Base(err)
-		}
-		errors.LogInfo(ctx, "listening TCP(for HttpUpgrade) on ", address, ":", port)
+		addr = &net.TCPAddr{IP: address.IP(), Port: int(port)}
 	}
-
-	if streamSettings.TcpmaskManager != nil {
-		listener, _ = streamSettings.TcpmaskManager.WrapListener(listener)
+	if streamSettings.FinalMask != nil {
+		listener, err = streamSettings.FinalMask.Listen(ctx, addr)
+	} else {
+		listener, err = internet.ListenSystem(ctx, addr, streamSettings.SocketSettings)
 	}
+	if err != nil {
+		return nil, errors.New("failed to listen ", addr.Network(), "(for HttpUpgrade) on ", address, ":", port).Base(err)
+	}
+	errors.LogInfo(ctx, "listening ", addr.Network(), "(for HttpUpgrade) on ", address, ":", port)
 
 	if streamSettings.SocketSettings != nil && streamSettings.SocketSettings.AcceptProxyProtocol {
 		errors.LogWarning(ctx, "accepting PROXY protocol")

transport/internet/hysteria/dialer.go

@@ -2,7 +2,7 @@ package hysteria
 
 import (
 	"context"
-	go_tls "crypto/tls"
+	gotls "crypto/tls"
 	"net/http"
 	"net/url"
 	"reflect"
@@ -28,12 +28,12 @@ import (
 type client struct {
 	sync.Mutex
 
-	dest           net.Destination
-	config         *Config
-	tlsConfig      *go_tls.Config
-	socketConfig   *internet.SocketConfig
-	udpmaskManager *finalmask.UdpmaskManager
-	quicParams     *internet.QuicParams
+	dest         net.Destination
+	config       *Config
+	tlsConfig    *gotls.Config
+	socketConfig *internet.SocketConfig
+	finalMask    *finalmask.FinalMask
+	quicParams   *internet.QuicParams
 
 	conn    *quic.Conn
 	tr      *quic.Transport
@@ -113,30 +113,29 @@ func (c *client) dial(ctx context.Context) error {
 	// }
 
 	var pktConn net.PacketConn
-	var udpAddr *net.UDPAddr
-
-	raw, err := internet.DialSystem(ctx, c.dest, c.socketConfig)
-	if err != nil {
-		return errors.New("failed to dial to dest").Base(err)
-	}
-	switch c := raw.(type) {
-	case *internet.PacketConnWrapper:
-		pktConn = c.PacketConn
-		udpAddr = raw.RemoteAddr().(*net.UDPAddr)
-	case *cnc.Connection:
-		pktConn = &internet.FakePacketConn{Conn: c}
-		udpAddr = &net.UDPAddr{IP: c.RemoteAddr().(*net.TCPAddr).IP, Port: c.RemoteAddr().(*net.TCPAddr).Port}
-	default:
-		panic(reflect.TypeOf(c))
-	}
-
-	if c.udpmaskManager != nil {
-		newConn, err := c.udpmaskManager.WrapPacketConnClient(pktConn)
+	var udpAddr net.Addr
+	if c.finalMask != nil {
+		conn, err := c.finalMask.DialUDP(ctx, c.dest)
 		if err != nil {
-			pktConn.Close()
-			return errors.New("mask err").Base(err)
+			return errors.New("failed to dial to dest").Base(err)
+		}
+		pktConn = conn.(*finalmask.PacketConnWrapper).PacketConn
+		udpAddr = conn.RemoteAddr()
+	} else {
+		conn, err := internet.DialSystem(ctx, c.dest, c.socketConfig)
+		if err != nil {
+			return errors.New("failed to dial to dest").Base(err)
+		}
+		switch c := conn.(type) {
+		case *internet.PacketConnWrapper:
+			pktConn = c.PacketConn
+			udpAddr = c.RemoteAddr()
+		case *cnc.Connection:
+			pktConn = &internet.FakePacketConn{Conn: c}
+			udpAddr = &net.UDPAddr{IP: []byte{0, 0, 0, 0}}
+		default:
+			panic(reflect.TypeOf(c))
 		}
-		pktConn = newConn
 	}
 
 	tr := &quic.Transport{Conn: pktConn, DisableGSO: quicParams.DisableGSO}
@@ -150,7 +149,7 @@ func (c *client) dial(ctx context.Context) error {
 	rt := &http3.Transport{
 		TLSClientConfig: c.tlsConfig,
 		QUICConfig:      quicConfig,
-		Dial: func(ctx context.Context, _ string, tlsCfg *go_tls.Config, cfg *quic.Config) (*quic.Conn, error) {
+		Dial: func(ctx context.Context, _ string, tlsCfg *gotls.Config, cfg *quic.Config) (*quic.Conn, error) {
 			qc, err := tr.DialEarly(ctx, udpAddr, tlsCfg, cfg)
 			if err != nil {
 				return nil, err
@@ -316,12 +315,12 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 		c = manager.m[dialerConf{dest, streamSettings}]
 		if c == nil {
 			c = &client{
-				dest:           dest,
-				config:         streamSettings.ProtocolSettings.(*Config),
-				tlsConfig:      tlsConfig.GetTLSConfig(tls.WithDestination(dest)),
-				socketConfig:   streamSettings.SocketSettings,
-				udpmaskManager: streamSettings.UdpmaskManager,
-				quicParams:     streamSettings.QuicParams,
+				dest:         dest,
+				config:       streamSettings.ProtocolSettings.(*Config),
+				tlsConfig:    tlsConfig.GetTLSConfig(tls.WithDestination(dest)),
+				socketConfig: streamSettings.SocketSettings,
+				finalMask:    streamSettings.FinalMask,
+				quicParams:   streamSettings.QuicParams,
 			}
 			manager.m[dialerConf{dest, streamSettings}] = c
 		}

transport/internet/hysteria/hub.go

@@ -316,20 +316,17 @@ func Listen(ctx context.Context, address net.Address, port net.Port, streamSetti
 		quicConfig.MaxIncomingStreams = 1024
 	}
 
-	pktConn, err := internet.ListenSystemPacket(context.Background(), &net.UDPAddr{IP: address.IP(), Port: int(port)}, streamSettings.SocketSettings)
+	var pktConn net.PacketConn
+	var err error
+	if streamSettings.FinalMask != nil {
+		pktConn, err = streamSettings.FinalMask.ListenPacket(context.Background(), &net.UDPAddr{IP: address.IP(), Port: int(port)})
+	} else {
+		pktConn, err = internet.ListenSystemPacket(context.Background(), &net.UDPAddr{IP: address.IP(), Port: int(port)}, streamSettings.SocketSettings)
+	}
 	if err != nil {
 		return nil, err
 	}
 
-	if streamSettings.UdpmaskManager != nil {
-		newConn, err := streamSettings.UdpmaskManager.WrapPacketConnServer(pktConn)
-		if err != nil {
-			pktConn.Close()
-			return nil, errors.New("mask err").Base(err)
-		}
-		pktConn = newConn
-	}
-
 	var k *quic.StatelessResetKey
 	if !quicParams.DisableStatelessReset {
 		k = &quic.StatelessResetKey{}

transport/internet/kcp/dialer.go

@@ -3,7 +3,6 @@ package kcp
 import (
 	"context"
 	"io"
-	reflect "reflect"
 	"sync/atomic"
 
 	"github.com/xtls/xray-core/common"
@@ -11,7 +10,6 @@ import (
 	"github.com/xtls/xray-core/common/dice"
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/net"
-	"github.com/xtls/xray-core/common/net/cnc"
 	"github.com/xtls/xray-core/transport/internet"
 	"github.com/xtls/xray-core/transport/internet/stat"
 	"github.com/xtls/xray-core/transport/internet/tls"
@@ -51,36 +49,17 @@ func DialKCP(ctx context.Context, dest net.Destination, streamSettings *internet
 	dest.Network = net.Network_UDP
 	errors.LogInfo(ctx, "dialing mKCP to ", dest)
 
-	conn, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
+	var conn net.Conn
+	var err error
+	if streamSettings.FinalMask != nil {
+		conn, err = streamSettings.FinalMask.DialUDP(ctx, dest)
+	} else {
+		conn, err = internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
+	}
 	if err != nil {
 		return nil, errors.New("failed to dial to dest: ", err).AtWarning().Base(err)
 	}
 
-	if streamSettings.UdpmaskManager != nil {
-		var pktConn net.PacketConn
-		var udpAddr *net.UDPAddr
-		switch c := conn.(type) {
-		case *internet.PacketConnWrapper:
-			pktConn = c.PacketConn
-			udpAddr = c.RemoteAddr().(*net.UDPAddr)
-		case *cnc.Connection:
-			pktConn = &internet.FakePacketConn{Conn: c}
-			udpAddr = &net.UDPAddr{IP: c.RemoteAddr().(*net.TCPAddr).IP, Port: c.RemoteAddr().(*net.TCPAddr).Port}
-		default:
-			panic(reflect.TypeOf(c))
-		}
-		newConn, err := streamSettings.UdpmaskManager.WrapPacketConnClient(pktConn)
-		if err != nil {
-			pktConn.Close()
-			return nil, errors.New("mask err").Base(err)
-		}
-		pktConn = newConn
-		conn = &internet.PacketConnWrapper{
-			PacketConn: pktConn,
-			Dest:       udpAddr,
-		}
-	}
-
 	kcpSettings := streamSettings.ProtocolSettings.(*Config)
 
 	reader := &KCPPacketReader{}

transport/internet/memory_settings.go

@@ -1,7 +1,12 @@
 package internet
 
 import (
+	"context"
+	"reflect"
+
+	"github.com/xtls/xray-core/common"
 	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/common/net/cnc"
 	"github.com/xtls/xray-core/transport/internet/finalmask"
 )
 
@@ -12,8 +17,7 @@ type MemoryStreamConfig struct {
 	ProtocolSettings interface{}
 	SecurityType     string
 	SecuritySettings interface{}
-	TcpmaskManager   *finalmask.TcpmaskManager
-	UdpmaskManager   *finalmask.UdpmaskManager
+	FinalMask        *finalmask.FinalMask
 	QuicParams       *QuicParams
 	SocketSettings   *SocketConfig
 	DownloadSettings *MemoryStreamConfig
@@ -51,33 +55,53 @@ func ToMemoryStreamConfig(s *StreamConfig) (*MemoryStreamConfig, error) {
 		mss.SecuritySettings = ess
 	}
 
-	if s != nil && len(s.Tcpmasks) > 0 {
-		var masks []finalmask.Tcpmask
-		for _, msg := range s.Tcpmasks {
-			instance, err := msg.GetInstance()
-			if err != nil {
-				return nil, err
-			}
-			masks = append(masks, instance.(finalmask.Tcpmask))
+	var tcpMasks []finalmask.TCPMask
+	var udpMasks []finalmask.UDPMask
+
+	if s != nil {
+		for i := range s.Tcpmasks {
+			instance := common.Must2(s.Tcpmasks[i].GetInstance())
+			tcpMasks = append(tcpMasks, instance.(finalmask.TCPMask))
+		}
+		for i := range s.Udpmasks {
+			instance := common.Must2(s.Udpmasks[i].GetInstance())
+			udpMasks = append(udpMasks, instance.(finalmask.UDPMask))
 		}
-		mss.TcpmaskManager = finalmask.NewTcpmaskManager(masks)
 	}
 
+	dialTCP := func(ctx context.Context, dest net.Destination) (net.Conn, error) {
+		return DialSystem(ctx, dest, mss.SocketSettings)
+	}
+	listen := func(ctx context.Context, addr net.Addr) (net.Listener, error) {
+		return ListenSystem(ctx, addr, mss.SocketSettings)
+	}
+	dialUDP := func(ctx context.Context, dest net.Destination) (net.PacketConn, net.Addr, error) {
+		conn, err := DialSystem(ctx, dest, mss.SocketSettings)
+		if err != nil {
+			return nil, nil, err
+		}
+		var newConn net.PacketConn
+		var udpAddr net.Addr
+		switch c := conn.(type) {
+		case *PacketConnWrapper:
+			newConn = c.PacketConn
+			udpAddr = conn.RemoteAddr()
+		case *cnc.Connection:
+			newConn = &FakePacketConn{Conn: c}
+			udpAddr = &net.UDPAddr{IP: []byte{0, 0, 0, 0}, Port: 0}
+		default:
+			panic(reflect.TypeOf(c))
+		}
+		return newConn, udpAddr, nil
+	}
+	listenPacket := func(ctx context.Context, addr net.Addr) (net.PacketConn, error) {
+		return ListenSystemPacket(ctx, addr, mss.SocketSettings)
+	}
+	mss.FinalMask = finalmask.NewFinalMask(tcpMasks, udpMasks, dialTCP, listen, dialUDP, listenPacket)
+
 	if s != nil && s.QuicParams != nil {
 		mss.QuicParams = s.QuicParams
 	}
 
-	if s != nil && len(s.Udpmasks) > 0 {
-		var masks []finalmask.Udpmask
-		for _, msg := range s.Udpmasks {
-			instance, err := msg.GetInstance()
-			if err != nil {
-				return nil, err
-			}
-			masks = append(masks, instance.(finalmask.Udpmask))
-		}
-		mss.UdpmaskManager = finalmask.NewUdpmaskManager(masks)
-	}
-
 	return mss, nil
 }

transport/internet/splithttp/dialer.go

@@ -8,7 +8,7 @@ import (
 	"net/http"
 	"net/http/httptrace"
 	"net/url"
-	reflect "reflect"
+	"reflect"
 	"runtime"
 	"strconv"
 	"sync"
@@ -25,6 +25,7 @@ import (
 	"github.com/xtls/xray-core/common/signal/done"
 	"github.com/xtls/xray-core/transport/internet"
 	"github.com/xtls/xray-core/transport/internet/browser_dialer"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
 	"github.com/xtls/xray-core/transport/internet/hysteria/congestion"
 	"github.com/xtls/xray-core/transport/internet/hysteria/congestion/bbr"
 	"github.com/xtls/xray-core/transport/internet/reality"
@@ -116,20 +117,17 @@ func createHTTPClient(dest net.Destination, streamSettings *internet.MemoryStrea
 	transportConfig := streamSettings.ProtocolSettings.(*Config)
 
 	dialContext := func(ctxInner context.Context) (net.Conn, error) {
-		conn, err := internet.DialSystem(ctxInner, dest, streamSettings.SocketSettings)
+		var conn net.Conn
+		var err error
+		if streamSettings.FinalMask != nil {
+			conn, err = streamSettings.FinalMask.DialTCP(ctxInner, dest)
+		} else {
+			conn, err = internet.DialSystem(ctxInner, dest, streamSettings.SocketSettings)
+		}
 		if err != nil {
 			return nil, err
 		}
 
-		if streamSettings.TcpmaskManager != nil {
-			newConn, err := streamSettings.TcpmaskManager.WrapConnClient(conn)
-			if err != nil {
-				conn.Close()
-				return nil, errors.New("mask err").Base(err)
-			}
-			conn = newConn
-		}
-
 		if realityConfig != nil {
 			return reality.UClient(conn, realityConfig, ctxInner, dest)
 		}
@@ -196,30 +194,29 @@ func createHTTPClient(dest net.Destination, streamSettings *internet.MemoryStrea
 			TLSClientConfig: gotlsConfig,
 			Dial: func(ctx context.Context, addr string, tlsCfg *gotls.Config, cfg *quic.Config) (*quic.Conn, error) {
 				var pktConn net.PacketConn
-				var udpAddr *net.UDPAddr
-
-				raw, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
-				if err != nil {
-					return nil, errors.New("failed to dial to dest").Base(err)
-				}
-				switch c := raw.(type) {
-				case *internet.PacketConnWrapper:
-					pktConn = c.PacketConn
-					udpAddr = raw.RemoteAddr().(*net.UDPAddr)
-				case *cnc.Connection:
-					pktConn = &internet.FakePacketConn{Conn: c}
-					udpAddr = &net.UDPAddr{IP: c.RemoteAddr().(*net.TCPAddr).IP, Port: c.RemoteAddr().(*net.TCPAddr).Port}
-				default:
-					panic(reflect.TypeOf(c))
-				}
-
-				if streamSettings.UdpmaskManager != nil {
-					newConn, err := streamSettings.UdpmaskManager.WrapPacketConnClient(pktConn)
+				var udpAddr net.Addr
+				if streamSettings.FinalMask != nil {
+					conn, err := streamSettings.FinalMask.DialUDP(ctx, dest)
 					if err != nil {
-						pktConn.Close()
-						return nil, errors.New("mask err").Base(err)
+						return nil, errors.New("failed to dial to dest").Base(err)
+					}
+					pktConn = conn.(*finalmask.PacketConnWrapper).PacketConn
+					udpAddr = conn.RemoteAddr()
+				} else {
+					conn, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
+					if err != nil {
+						return nil, errors.New("failed to dial to dest").Base(err)
+					}
+					switch c := conn.(type) {
+					case *internet.PacketConnWrapper:
+						pktConn = c.PacketConn
+						udpAddr = c.RemoteAddr()
+					case *cnc.Connection:
+						pktConn = &internet.FakePacketConn{Conn: c}
+						udpAddr = &net.UDPAddr{IP: []byte{0, 0, 0, 0}}
+					default:
+						panic(reflect.TypeOf(c))
 					}
-					pktConn = newConn
 				}
 
 				tr := &quic.Transport{Conn: pktConn, DisableGSO: quicParams.DisableGSO}

transport/internet/splithttp/hub.go

@@ -463,31 +463,17 @@ func ListenXH(ctx context.Context, address net.Address, port net.Port, streamSet
 	l.isH3 = len(tlsConfig.NextProtos) == 1 && tlsConfig.NextProtos[0] == "h3"
 
 	var err error
-	if port == net.Port(0) { // unix
-		l.listener, err = internet.ListenSystem(ctx, &net.UnixAddr{
-			Name: address.Domain(),
-			Net:  "unix",
-		}, streamSettings.SocketSettings)
-		if err != nil {
-			return nil, errors.New("failed to listen UNIX domain socket for XHTTP on ", address).Base(err)
+	if l.isH3 {
+		var pktConn net.PacketConn
+		var err error
+		if streamSettings.FinalMask != nil {
+			pktConn, err = streamSettings.FinalMask.ListenPacket(context.Background(), &net.UDPAddr{IP: address.IP(), Port: int(port)})
+		} else {
+			pktConn, err = internet.ListenSystemPacket(context.Background(), &net.UDPAddr{IP: address.IP(), Port: int(port)}, streamSettings.SocketSettings)
 		}
-		errors.LogInfo(ctx, "listening UNIX domain socket for XHTTP on ", address)
-	} else if l.isH3 { // quic
-		Conn, err := internet.ListenSystemPacket(context.Background(), &net.UDPAddr{
-			IP:   address.IP(),
-			Port: int(port),
-		}, streamSettings.SocketSettings)
 		if err != nil {
 			return nil, errors.New("failed to listen UDP for XHTTP/3 on ", address, ":", port).Base(err)
 		}
-		if streamSettings.UdpmaskManager != nil {
-			newConn, err := streamSettings.UdpmaskManager.WrapPacketConnServer(Conn)
-			if err != nil {
-				Conn.Close()
-				return nil, errors.New("mask err").Base(err)
-			}
-			Conn = newConn
-		}
 
 		quicParams := streamSettings.QuicParams
 		if quicParams == nil {
@@ -512,7 +498,7 @@ func ListenXH(ctx context.Context, address net.Address, port net.Port, streamSet
 			common.Must2(rand.Read((*k)[:]))
 		}
 
-		tr := &quic.Transport{Conn: Conn, DisableGSO: quicParams.DisableGSO, StatelessResetKey: k}
+		tr := &quic.Transport{Conn: pktConn, DisableGSO: quicParams.DisableGSO, StatelessResetKey: k}
 
 		l.h3listener, err = tr.ListenEarly(tlsConfig, quicConfig)
 		if err != nil {
@@ -534,21 +520,24 @@ func ListenXH(ctx context.Context, address net.Address, port net.Port, streamSet
 				errors.LogErrorInner(ctx, err, "failed to serve HTTP/3 for XHTTP/3")
 			}
 			_ = tr.Close()
-			_ = Conn.Close()
+			_ = pktConn.Close()
 		}()
-	} else { // tcp
-		l.listener, err = internet.ListenSystem(ctx, &net.TCPAddr{
-			IP:   address.IP(),
-			Port: int(port),
-		}, streamSettings.SocketSettings)
-		if err != nil {
-			return nil, errors.New("failed to listen TCP for XHTTP on ", address, ":", port).Base(err)
+	} else {
+		var addr net.Addr
+		if port == net.Port(0) { // unix
+			addr = &net.UnixAddr{Name: address.Domain(), Net: "unix"}
+		} else { // tcp
+			addr = &net.TCPAddr{IP: address.IP(), Port: int(port)}
 		}
-		errors.LogInfo(ctx, "listening TCP for XHTTP on ", address, ":", port)
-	}
-
-	if !l.isH3 && streamSettings.TcpmaskManager != nil {
-		l.listener, _ = streamSettings.TcpmaskManager.WrapListener(l.listener)
+		if streamSettings.FinalMask != nil {
+			l.listener, err = streamSettings.FinalMask.Listen(ctx, addr)
+		} else {
+			l.listener, err = internet.ListenSystem(ctx, addr, streamSettings.SocketSettings)
+		}
+		if err != nil {
+			return nil, errors.New("failed to listen ", addr.Network(), " for XHTTP on ", address, ":", port).Base(err)
+		}
+		errors.LogInfo(ctx, "listening ", addr.Network(), " for XHTTP on ", address, ":", port)
 	}
 
 	// tcp/unix (h1/h2)

transport/internet/system_dialer.go

@@ -235,5 +235,5 @@ func (c *FakePacketConn) WriteTo(p []byte, _ net.Addr) (n int, err error) {
 }
 
 func (c *FakePacketConn) LocalAddr() net.Addr {
-	return &net.UDPAddr{IP: c.Conn.LocalAddr().(*net.TCPAddr).IP, Port: c.Conn.LocalAddr().(*net.TCPAddr).Port}
+	return &net.UDPAddr{IP: []byte{0, 0, 0, 0}}
 }

transport/internet/tcp/dialer.go

@@ -19,18 +19,15 @@ import (
 // Dial dials a new TCP connection to the given destination.
 func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (stat.Connection, error) {
 	errors.LogInfo(ctx, "dialing TCP to ", dest)
-	conn, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
-	if err != nil {
-		return nil, err
+	var conn net.Conn
+	var err error
+	if streamSettings.FinalMask != nil {
+		conn, err = streamSettings.FinalMask.DialTCP(ctx, dest)
+	} else {
+		conn, err = internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
 	}
-
-	if streamSettings.TcpmaskManager != nil {
-		newConn, err := streamSettings.TcpmaskManager.WrapConnClient(conn)
-		if err != nil {
-			conn.Close()
-			return nil, errors.New("mask err").Base(err)
-		}
-		conn = newConn
+	if err != nil {
+		return nil, errors.New("failed to dial to dest").Base(err)
 	}
 
 	if config := tls.ConfigFromStreamSettings(streamSettings); config != nil {

transport/internet/tcp/hub.go

@@ -41,29 +41,21 @@ func ListenTCP(ctx context.Context, address net.Address, port net.Port, streamSe
 	}
 	var listener net.Listener
 	var err error
+	var addr net.Addr
 	if port == net.Port(0) { // unix
-		listener, err = internet.ListenSystem(ctx, &net.UnixAddr{
-			Name: address.Domain(),
-			Net:  "unix",
-		}, streamSettings.SocketSettings)
-		if err != nil {
-			return nil, errors.New("failed to listen Unix Domain Socket on ", address).Base(err)
-		}
-		errors.LogInfo(ctx, "listening Unix Domain Socket on ", address)
+		addr = &net.UnixAddr{Name: address.Domain(), Net: "unix"}
+	} else { // tcp
+		addr = &net.TCPAddr{IP: address.IP(), Port: int(port)}
+	}
+	if streamSettings.FinalMask != nil {
+		listener, err = streamSettings.FinalMask.Listen(ctx, addr)
 	} else {
-		listener, err = internet.ListenSystem(ctx, &net.TCPAddr{
-			IP:   address.IP(),
-			Port: int(port),
-		}, streamSettings.SocketSettings)
-		if err != nil {
-			return nil, errors.New("failed to listen TCP on ", address, ":", port).Base(err)
-		}
-		errors.LogInfo(ctx, "listening TCP on ", address, ":", port)
+		listener, err = internet.ListenSystem(ctx, addr, streamSettings.SocketSettings)
 	}
-
-	if streamSettings.TcpmaskManager != nil {
-		listener, _ = streamSettings.TcpmaskManager.WrapListener(listener)
+	if err != nil {
+		return nil, errors.New("failed to listen ", addr.Network(), " on ", address, ":", port).Base(err)
 	}
+	errors.LogInfo(ctx, "listening ", addr.Network(), " on ", address, ":", port)
 
 	if streamSettings.SocketSettings != nil && streamSettings.SocketSettings.AcceptProxyProtocol {
 		errors.LogWarning(ctx, "accepting PROXY protocol")

transport/internet/udp/dialer.go

@@ -2,12 +2,9 @@ package udp
 
 import (
 	"context"
-	"reflect"
 
 	"github.com/xtls/xray-core/common"
-	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/net"
-	"github.com/xtls/xray-core/common/net/cnc"
 	"github.com/xtls/xray-core/transport/internet"
 	"github.com/xtls/xray-core/transport/internet/stat"
 )
@@ -15,40 +12,14 @@ import (
 func init() {
 	common.Must(internet.RegisterTransportDialer(protocolName,
 		func(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (stat.Connection, error) {
-			var sockopt *internet.SocketConfig
-			if streamSettings != nil {
-				sockopt = streamSettings.SocketSettings
-			}
-			conn, err := internet.DialSystem(ctx, dest, sockopt)
-			if err != nil {
-				return nil, err
-			}
-
-			if streamSettings != nil && streamSettings.UdpmaskManager != nil {
-				var pktConn net.PacketConn
-				var udpAddr *net.UDPAddr
-				switch c := conn.(type) {
-				case *internet.PacketConnWrapper:
-					pktConn = c.PacketConn
-					udpAddr = c.RemoteAddr().(*net.UDPAddr)
-				case *cnc.Connection:
-					pktConn = &internet.FakePacketConn{Conn: c}
-					udpAddr = &net.UDPAddr{IP: c.RemoteAddr().(*net.TCPAddr).IP, Port: c.RemoteAddr().(*net.TCPAddr).Port}
-				default:
-					panic(reflect.TypeOf(c))
-				}
-				newConn, err := streamSettings.UdpmaskManager.WrapPacketConnClient(pktConn)
-				if err != nil {
-					pktConn.Close()
-					return nil, errors.New("mask err").Base(err)
-				}
-				pktConn = newConn
-				conn = &internet.PacketConnWrapper{
-					PacketConn: pktConn,
-					Dest:       udpAddr,
+			if streamSettings != nil && streamSettings.FinalMask != nil {
+				return streamSettings.FinalMask.DialUDP(ctx, dest)
+			} else {
+				var sockopt *internet.SocketConfig
+				if streamSettings != nil && streamSettings.SocketSettings != nil {
+					sockopt = streamSettings.SocketSettings
 				}
+				return internet.DialSystem(ctx, dest, sockopt)
 			}
-
-			return conn, nil
 		}))
 }

transport/internet/udp/hub.go

@@ -58,24 +58,15 @@ func ListenUDP(ctx context.Context, address net.Address, port net.Port, streamSe
 	}
 
 	var err error
-	hub.conn, err = internet.ListenSystemPacket(ctx, &net.UDPAddr{
-		IP:   address.IP(),
-		Port: int(port),
-	}, sockopt)
+	if streamSettings.FinalMask != nil {
+		hub.conn, err = streamSettings.FinalMask.ListenPacket(ctx, &net.UDPAddr{IP: address.IP(), Port: int(port)})
+	} else {
+		hub.conn, err = internet.ListenSystemPacket(ctx, &net.UDPAddr{IP: address.IP(), Port: int(port)}, streamSettings.SocketSettings)
+	}
 	if err != nil {
 		return nil, err
 	}
 
-	raw := hub.conn
-
-	if streamSettings.UdpmaskManager != nil {
-		hub.conn, err = streamSettings.UdpmaskManager.WrapPacketConnServer(raw)
-		if err != nil {
-			raw.Close()
-			return nil, errors.New("mask err").Base(err)
-		}
-	}
-
 	errors.LogInfo(ctx, "listening UDP on ", address, ":", port)
 	hub.udpConn, _ = hub.conn.(*net.UDPConn)
 	hub.cache = make(chan *udp.Packet, hub.capacity)

transport/internet/websocket/dialer.go

@@ -48,20 +48,16 @@ func dialWebSocket(ctx context.Context, dest net.Destination, streamSettings *in
 
 	dialer := &websocket.Dialer{
 		NetDial: func(network, addr string) (net.Conn, error) {
-			conn, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
+			var conn net.Conn
+			var err error
+			if streamSettings.FinalMask != nil {
+				conn, err = streamSettings.FinalMask.DialTCP(ctx, dest)
+			} else {
+				conn, err = internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
+			}
 			if err != nil {
-				return nil, err
+				return nil, errors.New("failed to dial to dest").Base(err)
 			}
-
-			if streamSettings.TcpmaskManager != nil {
-				newConn, err := streamSettings.TcpmaskManager.WrapConnClient(conn)
-				if err != nil {
-					conn.Close()
-					return nil, errors.New("mask err").Base(err)
-				}
-				conn = newConn
-			}
-
 			return conn, err
 		},
 		ReadBufferSize:   4 * 1024,
@@ -79,19 +75,15 @@ func dialWebSocket(ctx context.Context, dest net.Destination, streamSettings *in
 		if fingerprint := tls.GetFingerprint(tConfig.Fingerprint); fingerprint != nil {
 			dialer.NetDialTLSContext = func(_ context.Context, _, addr string) (net.Conn, error) {
 				// Like the NetDial in the dialer
-				pconn, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
-				if err != nil {
-					errors.LogErrorInner(ctx, err, "failed to dial to "+addr)
-					return nil, err
+				var pconn net.Conn
+				var err error
+				if streamSettings.FinalMask != nil {
+					pconn, err = streamSettings.FinalMask.DialTCP(ctx, dest)
+				} else {
+					pconn, err = internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
 				}
-
-				if streamSettings.TcpmaskManager != nil {
-					newConn, err := streamSettings.TcpmaskManager.WrapConnClient(pconn)
-					if err != nil {
-						pconn.Close()
-						return nil, errors.New("mask err").Base(err)
-					}
-					pconn = newConn
+				if err != nil {
+					return nil, errors.New("failed to dial to dest").Base(err)
 				}
 
 				// TLS and apply the handshake

transport/internet/websocket/hub.go

@@ -97,29 +97,21 @@ func ListenWS(ctx context.Context, address net.Address, port net.Port, streamSet
 	}
 	var listener net.Listener
 	var err error
+	var addr net.Addr
 	if port == net.Port(0) { // unix
-		listener, err = internet.ListenSystem(ctx, &net.UnixAddr{
-			Name: address.Domain(),
-			Net:  "unix",
-		}, streamSettings.SocketSettings)
-		if err != nil {
-			return nil, errors.New("failed to listen unix domain socket(for WS) on ", address).Base(err)
-		}
-		errors.LogInfo(ctx, "listening unix domain socket(for WS) on ", address)
+		addr = &net.UnixAddr{Name: address.Domain(), Net: "unix"}
 	} else { // tcp
-		listener, err = internet.ListenSystem(ctx, &net.TCPAddr{
-			IP:   address.IP(),
-			Port: int(port),
-		}, streamSettings.SocketSettings)
-		if err != nil {
-			return nil, errors.New("failed to listen TCP(for WS) on ", address, ":", port).Base(err)
-		}
-		errors.LogInfo(ctx, "listening TCP(for WS) on ", address, ":", port)
+		addr = &net.TCPAddr{IP: address.IP(), Port: int(port)}
 	}
-
-	if streamSettings.TcpmaskManager != nil {
-		listener, _ = streamSettings.TcpmaskManager.WrapListener(listener)
+	if streamSettings.FinalMask != nil {
+		listener, err = streamSettings.FinalMask.Listen(ctx, addr)
+	} else {
+		listener, err = internet.ListenSystem(ctx, addr, streamSettings.SocketSettings)
 	}
+	if err != nil {
+		return nil, errors.New("failed to listen ", addr.Network(), "(for WS) on ", address, ":", port).Base(err)
+	}
+	errors.LogInfo(ctx, "listening ", addr.Network(), "(for WS) on ", address, ":", port)
 
 	if streamSettings.SocketSettings != nil && streamSettings.SocketSettings.AcceptProxyProtocol {
 		errors.LogWarning(ctx, "accepting PROXY protocol")

transport/internet/xdrive/client.go

@@ -55,17 +55,14 @@ func newServiceClient(streamSettings *internet.MemoryStreamConfig, timeout time.
 			}
 		}
 
-		conn, err := internet.DialSystem(ctx, target, sockopt)
-		if err != nil {
-			return nil, host, err
+		var conn net.Conn
+		if streamSettings.FinalMask != nil {
+			conn, err = streamSettings.FinalMask.DialTCP(ctx, target)
+		} else {
+			conn, err = internet.DialSystem(ctx, target, sockopt)
 		}
-		if streamSettings != nil && streamSettings.TcpmaskManager != nil {
-			masked, err := streamSettings.TcpmaskManager.WrapConnClient(conn)
-			if err != nil {
-				conn.Close()
-				return nil, host, errors.New("mask err").Base(err)
-			}
-			conn = masked
+		if err != nil {
+			return nil, host, errors.New("failed to dial to dest").Base(err)
 		}
 		return conn, host, nil
 	}