diff --git a/infra/conf/transport_finalmask.go b/infra/conf/transport_finalmask.go
index e4c579dda117..959b80f634d2 100644
--- a/infra/conf/transport_finalmask.go
+++ b/infra/conf/transport_finalmask.go
@@ -20,6 +20,7 @@ import (
 	"github.com/xtls/xray-core/transport/internet/finalmask/mkcp/header"
 	"github.com/xtls/xray-core/transport/internet/finalmask/mkcp/original"
 	"github.com/xtls/xray-core/transport/internet/finalmask/noise"
+	"github.com/xtls/xray-core/transport/internet/finalmask/rawpacket"
 	"github.com/xtls/xray-core/transport/internet/finalmask/realm"
 	"github.com/xtls/xray-core/transport/internet/finalmask/salamander"
 	"github.com/xtls/xray-core/transport/internet/finalmask/sudoku"
@@ -70,6 +71,7 @@ var (
 	tcpmaskLoader = NewJSONConfigLoader(ConfigCreatorCache{
 		"header-custom": func() interface{} { return new(HeaderCustomTCP) },
 		"fragment":      func() interface{} { return new(FragmentMask) },
+		"rawpacket":     func() interface{} { return new(RawpacketMask) },
 		"sudoku":        func() interface{} { return new(Sudoku) },
 		"xmc":           func() interface{} { return new(XMC) },
 	}, "type", "settings")
@@ -231,6 +233,55 @@ func (c *HeaderCustomTCP) Build() (proto.Message, error) {
 	}, nil
 }
 
+type RawpacketMask struct {
+	Mode          string   `json:"mode"`
+	RemoteAddress string   `json:"remoteAddress"`
+	RemotePort    uint16   `json:"remotePort"`
+	RecvPort      uint16   `json:"recvPort"`
+	SpoofIPs      []string `json:"spoofIPs"`
+	Protocols     []string `json:"protocols"`
+	MTU           uint16   `json:"mtu"`
+	Target        string   `json:"target"`
+	TTL           uint8    `json:"ttl"`
+	SendTransport string   `json:"sendTransport"`
+	RecvTransport string   `json:"recvTransport"`
+	RelayAddress  string   `json:"relayAddress"`
+	RelayPort     uint16   `json:"relayPort"`
+	ClientIP      string   `json:"clientIP"`
+	ClientPort    uint16   `json:"clientPort"`
+	PeerSpoofIP   string   `json:"peerSpoofIP"`
+	SpoofPort     uint16   `json:"spoofPort"`
+	Auth          string   `json:"auth"`
+	SuppressRst   bool     `json:"suppressRst"`
+	Masquerade    string   `json:"masquerade"`
+}
+
+func (c *RawpacketMask) Build() (proto.Message, error) {
+	config := &rawpacket.Config{
+		Mode:          c.Mode,
+		RemoteAddress: c.RemoteAddress,
+		RemotePort:    uint32(c.RemotePort),
+		RecvPort:      uint32(c.RecvPort),
+		SpoofIps:      c.SpoofIPs,
+		Protocols:     c.Protocols,
+		Mtu:           uint32(c.MTU),
+		Target:        c.Target,
+		Ttl:           uint32(c.TTL),
+		SendTransport: c.SendTransport,
+		RecvTransport: c.RecvTransport,
+		RelayAddress:  c.RelayAddress,
+		RelayPort:     uint32(c.RelayPort),
+		ClientIp:      c.ClientIP,
+		ClientPort:    uint32(c.ClientPort),
+		PeerSpoofIp:   c.PeerSpoofIP,
+		SpoofPort:     uint32(c.SpoofPort),
+		Auth:          c.Auth,
+		SuppressRst:   c.SuppressRst,
+		Masquerade:    c.Masquerade,
+	}
+	return config, nil
+}
+
 type FragmentMask struct {
 	Packets  string       `json:"packets"`
 	Length   Int32Range   `json:"length"`
diff --git a/infra/conf/transport_internet.go b/infra/conf/transport_internet.go
index 24b5fba7c805..eace84880206 100644
--- a/infra/conf/transport_internet.go
+++ b/infra/conf/transport_internet.go
@@ -17,6 +17,8 @@ func (p TransportProtocol) Build() (string, error) {
 	switch strings.ToLower(string(p)) {
 	case "raw", "tcp":
 		return "tcp", nil
+	case "rawpacket":
+		return "rawpacket", nil
 	case "xhttp", "splithttp":
 		return "splithttp", nil
 	case "kcp", "mkcp":
@@ -48,6 +50,7 @@ type StreamConfig struct {
 	Network             *TransportProtocol `json:"network"`
 	Security            string             `json:"security"`
 	FinalMask           *FinalMask         `json:"finalmask"`
+	RawpacketSettings   *RawpacketMask     `json:"rawpacketSettings"`
 	TLSSettings         *TLSConfig         `json:"tlsSettings"`
 	REALITYSettings     *REALITYConfig     `json:"realitySettings"`
 	RAWSettings         *TCPConfig         `json:"rawSettings"`
@@ -182,6 +185,16 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 			Settings:     serial.ToTypedMessage(hs),
 		})
 	}
+	if c.RawpacketSettings != nil {
+		rs, err := c.RawpacketSettings.Build()
+		if err != nil {
+			return nil, errors.New("Failed to build rawpacket config.").Base(err)
+		}
+		config.TransportSettings = append(config.TransportSettings, &internet.TransportConfig{
+			ProtocolName: "rawpacket",
+			Settings:     serial.ToTypedMessage(rs),
+		})
+	}
 	if c.HysteriaSettings != nil {
 		hs, err := c.HysteriaSettings.Build()
 		if err != nil {
diff --git a/main/commands/all/tls/fakehello.go b/main/commands/all/tls/fakehello.go
new file mode 100644
index 000000000000..d7d84bca6041
--- /dev/null
+++ b/main/commands/all/tls/fakehello.go
@@ -0,0 +1,48 @@
+package tls
+
+import (
+	"encoding/base64"
+	"fmt"
+	"os"
+
+	"github.com/xtls/xray-core/main/commands/base"
+	"github.com/xtls/xray-core/transport/internet/finalmask/rawpacket"
+)
+
+var cmdFakeHello = &base.Command{
+	UsageLine: "{{.Exec}} tls fake-hello [-hex] <sni>",
+	Short:     "Generate a fake TLS ClientHello payload for rawpacket",
+	Long: `
+Generate a fake TLS ClientHello for use in finalmask rawpacket settings.
+
+Arguments:
+
+	-base64
+		Output base64-encoded payload (default).
+	-hex
+		Output hex-encoded payload instead of base64.
+`,
+}
+
+func init() {
+	cmdFakeHello.Run = executeFakeHello
+}
+
+var fakeHelloHex = cmdFakeHello.Flag.Bool("hex", false, "")
+
+func executeFakeHello(cmd *base.Command, args []string) {
+	if cmdFakeHello.Flag.NArg() < 1 {
+		base.Fatalf("sni not specified")
+	}
+	sni := cmdFakeHello.Flag.Arg(0)
+	payload, err := rawpacket.BuildFakeClientHello(sni)
+	if err != nil {
+		base.Fatalf("failed to build ClientHello: %s", err)
+	}
+	switch {
+	case *fakeHelloHex:
+		fmt.Fprintf(os.Stdout, "%x\n", payload)
+	default:
+		fmt.Fprintln(os.Stdout, base64.StdEncoding.EncodeToString(payload))
+	}
+}
diff --git a/main/commands/all/tls/tls.go b/main/commands/all/tls/tls.go
index 17a9465a7851..27bc4e8c373c 100644
--- a/main/commands/all/tls/tls.go
+++ b/main/commands/all/tls/tls.go
@@ -15,5 +15,6 @@ var CmdTLS = &base.Command{
 		cmdPing,
 		cmdHash,
 		cmdECH,
+		cmdFakeHello,
 	},
 }
diff --git a/transport/internet/finalmask/rawpacket/client_hello.go b/transport/internet/finalmask/rawpacket/client_hello.go
new file mode 100644
index 000000000000..04eec64584da
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/client_hello.go
@@ -0,0 +1,51 @@
+package rawpacket
+
+import (
+	"bytes"
+	"context"
+	"crypto/tls"
+	"errors"
+	"io"
+	"net"
+	"time"
+)
+
+// BuildFakeClientHello drives crypto/tls against a write-only in-memory conn
+// to capture a generated ClientHello. CurvePreferences pins classical groups
+// to suppress Go's default X25519MLKEM768 hybrid key share; without this the
+// post-quantum public key alone (~1184 bytes) pushes the record past one MSS,
+// and middleboxes do not reassemble fragmented ClientHellos. The handshake
+// error is discarded because the stub conn's Read returns immediately.
+func BuildFakeClientHello(sni string) ([]byte, error) {
+	if sni == "" {
+		return nil, errors.New("empty sni")
+	}
+	var buf bytes.Buffer
+	tlsConn := tls.Client(&writeOnlyConn{w: &buf}, &tls.Config{
+		ServerName: sni,
+		// Order matches what browsers advertised before post-quantum.
+		CurvePreferences:   []tls.CurveID{tls.X25519, tls.CurveP256, tls.CurveP384},
+		MinVersion:         tls.VersionTLS12,
+		MaxVersion:         tls.VersionTLS13,
+		NextProtos:         []string{"h2", "http/1.1"},
+		InsecureSkipVerify: true,
+	})
+	_ = tlsConn.HandshakeContext(context.Background())
+	if buf.Len() == 0 {
+		return nil, errors.New("tls ClientHello not produced")
+	}
+	return buf.Bytes(), nil
+}
+
+type writeOnlyConn struct {
+	w io.Writer
+}
+
+func (c *writeOnlyConn) Read([]byte) (int, error)         { return 0, io.EOF }
+func (c *writeOnlyConn) Write(p []byte) (int, error)      { return c.w.Write(p) }
+func (c *writeOnlyConn) Close() error                     { return nil }
+func (c *writeOnlyConn) LocalAddr() net.Addr              { return nil }
+func (c *writeOnlyConn) RemoteAddr() net.Addr             { return nil }
+func (c *writeOnlyConn) SetDeadline(time.Time) error      { return nil }
+func (c *writeOnlyConn) SetReadDeadline(time.Time) error  { return nil }
+func (c *writeOnlyConn) SetWriteDeadline(time.Time) error { return nil }
diff --git a/transport/internet/finalmask/rawpacket/config.go b/transport/internet/finalmask/rawpacket/config.go
new file mode 100644
index 000000000000..a82e30ecb36a
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/config.go
@@ -0,0 +1,60 @@
+package rawpacket
+
+import (
+	"fmt"
+	"net/netip"
+	"strings"
+)
+
+const (
+	ProtocolTCP    uint8 = 6
+	ProtocolICMP   uint8 = 1
+	ProtocolICMPv6 uint8 = 58
+	ProtocolUDP    uint8 = 17
+)
+
+func ParseProtocol(s string) (uint8, error) {
+	switch strings.ToLower(s) {
+	case "tcp":
+		return ProtocolTCP, nil
+	case "icmp":
+		return ProtocolICMP, nil
+	case "icmpv6":
+		return ProtocolICMPv6, nil
+	case "udp":
+		return ProtocolUDP, nil
+	default:
+		return 0, fmt.Errorf("rawpacket: unknown protocol: %s", s)
+	}
+}
+
+func ParseIPs(ss []string) ([]netip.Addr, error) {
+	var out []netip.Addr
+	for _, s := range ss {
+		ip, err := netip.ParseAddr(s)
+		if err != nil {
+			return nil, fmt.Errorf("rawpacket: invalid spoof IP %q: %w", s, err)
+		}
+		out = append(out, ip.Unmap())
+	}
+	return out, nil
+}
+
+type RelayConfig struct {
+	ListenPort       uint16
+	ForwardAddr      string
+	ForwardTransport string // "tcp" (Xray) or "udp" (reference, default)
+	ClientIP         netip.Addr
+	ClientPort       uint16
+	SpoofIP          netip.Addr // single fallback
+	SpoofIPs         []string
+	SpoofPort        uint16
+	PeerSpoofIP      netip.Addr
+	SendTransport    string
+	RecvTransport    string
+	Mtu              uint32
+	SuppressRst      bool
+	Masquerade       string // "off" | "http" | "tls" | "dns"
+	Auth             []byte
+	icmpSuppressed   bool
+}
diff --git a/transport/internet/finalmask/rawpacket/config.pb.go b/transport/internet/finalmask/rawpacket/config.pb.go
new file mode 100644
index 000000000000..3704f09f977f
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/config.pb.go
@@ -0,0 +1,326 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.36.11
+// 	protoc        v7.35.1
+// source: transport/internet/finalmask/rawpacket/config.proto
+
+package rawpacket
+
+import (
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+	unsafe "unsafe"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+type Config struct {
+	state protoimpl.MessageState `protogen:"open.v1"`
+	// Mode: "local" (client) or "remote" (server).
+	Mode string `protobuf:"bytes,6,opt,name=mode,proto3" json:"mode,omitempty"`
+	// Remote server address (local/client mode).
+	RemoteAddress string `protobuf:"bytes,7,opt,name=remote_address,json=remoteAddress,proto3" json:"remote_address,omitempty"`
+	// Remote server port (client mode).
+	RemotePort uint32 `protobuf:"varint,8,opt,name=remote_port,json=remotePort,proto3" json:"remote_port,omitempty"`
+	// Local port for receiving responses from the relay (client mode).
+	RecvPort uint32 `protobuf:"varint,9,opt,name=recv_port,json=recvPort,proto3" json:"recv_port,omitempty"`
+	// List of IP addresses to spoof as source.
+	SpoofIps []string `protobuf:"bytes,10,rep,name=spoof_ips,json=spoofIps,proto3" json:"spoof_ips,omitempty"`
+	// List of transport protocols to use: tcp, udp, icmp, icmpv6.
+	Protocols []string `protobuf:"bytes,11,rep,name=protocols,proto3" json:"protocols,omitempty"`
+	// MTU for packet fragmentation.
+	Mtu uint32 `protobuf:"varint,12,opt,name=mtu,proto3" json:"mtu,omitempty"`
+	// Target address for the relay (e.g. "127.0.0.1:443").
+	Target string `protobuf:"bytes,13,opt,name=target,proto3" json:"target,omitempty"`
+	// TTL for outgoing packets.
+	Ttl uint32 `protobuf:"varint,14,opt,name=ttl,proto3" json:"ttl,omitempty"`
+	// Send transport: "tcp", "udp", "icmp", "icmpv6" (default: "tcp").
+	SendTransport string `protobuf:"bytes,15,opt,name=send_transport,json=sendTransport,proto3" json:"send_transport,omitempty"`
+	// Receive transport: "tcp", "udp", "icmp", "icmpv6" (default: "udp").
+	RecvTransport string `protobuf:"bytes,16,opt,name=recv_transport,json=recvTransport,proto3" json:"recv_transport,omitempty"`
+	// Relay address (for the relay sender, defaults to first spoof IP).
+	RelayAddress string `protobuf:"bytes,17,opt,name=relay_address,json=relayAddress,proto3" json:"relay_address,omitempty"`
+	// Port the relay listens on (remote/server mode).
+	RelayPort uint32 `protobuf:"varint,18,opt,name=relay_port,json=relayPort,proto3" json:"relay_port,omitempty"`
+	// Client IP address (remote/server mode) — where to send responses.
+	ClientIp string `protobuf:"bytes,19,opt,name=client_ip,json=clientIp,proto3" json:"client_ip,omitempty"`
+	// Client port (remote/server mode).
+	ClientPort uint32 `protobuf:"varint,20,opt,name=client_port,json=clientPort,proto3" json:"client_port,omitempty"`
+	// Expected peer spoof IP for receive filtering (nil = accept all).
+	PeerSpoofIp string `protobuf:"bytes,21,opt,name=peer_spoof_ip,json=peerSpoofIp,proto3" json:"peer_spoof_ip,omitempty"`
+	// Source port to use in spoofed packets (default: 443).
+	SpoofPort uint32 `protobuf:"varint,22,opt,name=spoof_port,json=spoofPort,proto3" json:"spoof_port,omitempty"`
+	// Pre-shared key authenticating and encrypting the tunnel. Required
+	// in both modes; must match on client and relay.
+	Auth string `protobuf:"bytes,23,opt,name=auth,proto3" json:"auth,omitempty"`
+	// Suppress kernel-generated TCP RST for the relay's listen port
+	// (Linux only; uses iptables OUTPUT REJECT rules). Prevents the kernel
+	// from answering the fake TCP handshake with RST.
+	SuppressRst bool `protobuf:"varint,24,opt,name=suppress_rst,json=suppressRst,proto3" json:"suppress_rst,omitempty"`
+	// Masquerade for non-tunnel traffic (probes, scanners): "http" or
+	// "tls" serve a fake web service to TCP probes, "dns" answers UDP
+	// queries. Empty or "off" disables.
+	Masquerade    string `protobuf:"bytes,26,opt,name=masquerade,proto3" json:"masquerade,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *Config) Reset() {
+	*x = Config{}
+	mi := &file_transport_internet_finalmask_rawpacket_config_proto_msgTypes[0]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *Config) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Config) ProtoMessage() {}
+
+func (x *Config) ProtoReflect() protoreflect.Message {
+	mi := &file_transport_internet_finalmask_rawpacket_config_proto_msgTypes[0]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use Config.ProtoReflect.Descriptor instead.
+func (*Config) Descriptor() ([]byte, []int) {
+	return file_transport_internet_finalmask_rawpacket_config_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *Config) GetMode() string {
+	if x != nil {
+		return x.Mode
+	}
+	return ""
+}
+
+func (x *Config) GetRemoteAddress() string {
+	if x != nil {
+		return x.RemoteAddress
+	}
+	return ""
+}
+
+func (x *Config) GetRemotePort() uint32 {
+	if x != nil {
+		return x.RemotePort
+	}
+	return 0
+}
+
+func (x *Config) GetRecvPort() uint32 {
+	if x != nil {
+		return x.RecvPort
+	}
+	return 0
+}
+
+func (x *Config) GetSpoofIps() []string {
+	if x != nil {
+		return x.SpoofIps
+	}
+	return nil
+}
+
+func (x *Config) GetProtocols() []string {
+	if x != nil {
+		return x.Protocols
+	}
+	return nil
+}
+
+func (x *Config) GetMtu() uint32 {
+	if x != nil {
+		return x.Mtu
+	}
+	return 0
+}
+
+func (x *Config) GetTarget() string {
+	if x != nil {
+		return x.Target
+	}
+	return ""
+}
+
+func (x *Config) GetTtl() uint32 {
+	if x != nil {
+		return x.Ttl
+	}
+	return 0
+}
+
+func (x *Config) GetSendTransport() string {
+	if x != nil {
+		return x.SendTransport
+	}
+	return ""
+}
+
+func (x *Config) GetRecvTransport() string {
+	if x != nil {
+		return x.RecvTransport
+	}
+	return ""
+}
+
+func (x *Config) GetRelayAddress() string {
+	if x != nil {
+		return x.RelayAddress
+	}
+	return ""
+}
+
+func (x *Config) GetRelayPort() uint32 {
+	if x != nil {
+		return x.RelayPort
+	}
+	return 0
+}
+
+func (x *Config) GetClientIp() string {
+	if x != nil {
+		return x.ClientIp
+	}
+	return ""
+}
+
+func (x *Config) GetClientPort() uint32 {
+	if x != nil {
+		return x.ClientPort
+	}
+	return 0
+}
+
+func (x *Config) GetPeerSpoofIp() string {
+	if x != nil {
+		return x.PeerSpoofIp
+	}
+	return ""
+}
+
+func (x *Config) GetSpoofPort() uint32 {
+	if x != nil {
+		return x.SpoofPort
+	}
+	return 0
+}
+
+func (x *Config) GetAuth() string {
+	if x != nil {
+		return x.Auth
+	}
+	return ""
+}
+
+func (x *Config) GetSuppressRst() bool {
+	if x != nil {
+		return x.SuppressRst
+	}
+	return false
+}
+
+func (x *Config) GetMasquerade() string {
+	if x != nil {
+		return x.Masquerade
+	}
+	return ""
+}
+
+var File_transport_internet_finalmask_rawpacket_config_proto protoreflect.FileDescriptor
+
+const file_transport_internet_finalmask_rawpacket_config_proto_rawDesc = "" +
+	"\n" +
+	"3transport/internet/finalmask/rawpacket/config.proto\x12+xray.transport.internet.finalmask.rawpacket\"\xe2\x04\n" +
+	"\x06Config\x12\x12\n" +
+	"\x04mode\x18\x06 \x01(\tR\x04mode\x12%\n" +
+	"\x0eremote_address\x18\a \x01(\tR\rremoteAddress\x12\x1f\n" +
+	"\vremote_port\x18\b \x01(\rR\n" +
+	"remotePort\x12\x1b\n" +
+	"\trecv_port\x18\t \x01(\rR\brecvPort\x12\x1b\n" +
+	"\tspoof_ips\x18\n" +
+	" \x03(\tR\bspoofIps\x12\x1c\n" +
+	"\tprotocols\x18\v \x03(\tR\tprotocols\x12\x10\n" +
+	"\x03mtu\x18\f \x01(\rR\x03mtu\x12\x16\n" +
+	"\x06target\x18\r \x01(\tR\x06target\x12\x10\n" +
+	"\x03ttl\x18\x0e \x01(\rR\x03ttl\x12%\n" +
+	"\x0esend_transport\x18\x0f \x01(\tR\rsendTransport\x12%\n" +
+	"\x0erecv_transport\x18\x10 \x01(\tR\rrecvTransport\x12#\n" +
+	"\rrelay_address\x18\x11 \x01(\tR\frelayAddress\x12\x1d\n" +
+	"\n" +
+	"relay_port\x18\x12 \x01(\rR\trelayPort\x12\x1b\n" +
+	"\tclient_ip\x18\x13 \x01(\tR\bclientIp\x12\x1f\n" +
+	"\vclient_port\x18\x14 \x01(\rR\n" +
+	"clientPort\x12\"\n" +
+	"\rpeer_spoof_ip\x18\x15 \x01(\tR\vpeerSpoofIp\x12\x1d\n" +
+	"\n" +
+	"spoof_port\x18\x16 \x01(\rR\tspoofPort\x12\x12\n" +
+	"\x04auth\x18\x17 \x01(\tR\x04auth\x12!\n" +
+	"\fsuppress_rst\x18\x18 \x01(\bR\vsuppressRst\x12\x1e\n" +
+	"\n" +
+	"masquerade\x18\x1a \x01(\tR\n" +
+	"masqueradeB\xa3\x01\n" +
+	"/com.xray.transport.internet.finalmask.rawpacketP\x01Z@github.com/xtls/xray-core/transport/internet/finalmask/rawpacket\xaa\x02+Xray.Transport.Internet.Finalmask.Rawpacketb\x06proto3"
+
+var (
+	file_transport_internet_finalmask_rawpacket_config_proto_rawDescOnce sync.Once
+	file_transport_internet_finalmask_rawpacket_config_proto_rawDescData []byte
+)
+
+func file_transport_internet_finalmask_rawpacket_config_proto_rawDescGZIP() []byte {
+	file_transport_internet_finalmask_rawpacket_config_proto_rawDescOnce.Do(func() {
+		file_transport_internet_finalmask_rawpacket_config_proto_rawDescData = protoimpl.X.CompressGZIP(unsafe.Slice(unsafe.StringData(file_transport_internet_finalmask_rawpacket_config_proto_rawDesc), len(file_transport_internet_finalmask_rawpacket_config_proto_rawDesc)))
+	})
+	return file_transport_internet_finalmask_rawpacket_config_proto_rawDescData
+}
+
+var file_transport_internet_finalmask_rawpacket_config_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
+var file_transport_internet_finalmask_rawpacket_config_proto_goTypes = []any{
+	(*Config)(nil), // 0: xray.transport.internet.finalmask.rawpacket.Config
+}
+var file_transport_internet_finalmask_rawpacket_config_proto_depIdxs = []int32{
+	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_rawpacket_config_proto_init() }
+func file_transport_internet_finalmask_rawpacket_config_proto_init() {
+	if File_transport_internet_finalmask_rawpacket_config_proto != nil {
+		return
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: unsafe.Slice(unsafe.StringData(file_transport_internet_finalmask_rawpacket_config_proto_rawDesc), len(file_transport_internet_finalmask_rawpacket_config_proto_rawDesc)),
+			NumEnums:      0,
+			NumMessages:   1,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_transport_internet_finalmask_rawpacket_config_proto_goTypes,
+		DependencyIndexes: file_transport_internet_finalmask_rawpacket_config_proto_depIdxs,
+		MessageInfos:      file_transport_internet_finalmask_rawpacket_config_proto_msgTypes,
+	}.Build()
+	File_transport_internet_finalmask_rawpacket_config_proto = out.File
+	file_transport_internet_finalmask_rawpacket_config_proto_goTypes = nil
+	file_transport_internet_finalmask_rawpacket_config_proto_depIdxs = nil
+}
diff --git a/transport/internet/finalmask/rawpacket/config.proto b/transport/internet/finalmask/rawpacket/config.proto
new file mode 100644
index 000000000000..82f83023701a
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/config.proto
@@ -0,0 +1,74 @@
+syntax = "proto3";
+
+package xray.transport.internet.finalmask.rawpacket;
+option csharp_namespace = "Xray.Transport.Internet.Finalmask.Rawpacket";
+option go_package = "github.com/xtls/xray-core/transport/internet/finalmask/rawpacket";
+option java_package = "com.xray.transport.internet.finalmask.rawpacket";
+option java_multiple_files = true;
+
+message Config {
+  // Mode: "local" (client) or "remote" (server).
+  string mode = 6;
+
+  // Remote server address (local/client mode).
+  string remote_address = 7;
+
+  // Remote server port (client mode).
+  uint32 remote_port = 8;
+
+  // Local port for receiving responses from the relay (client mode).
+  uint32 recv_port = 9;
+
+  // List of IP addresses to spoof as source.
+  repeated string spoof_ips = 10;
+
+  // List of transport protocols to use: tcp, udp, icmp, icmpv6.
+  repeated string protocols = 11;
+
+  // MTU for packet fragmentation.
+  uint32 mtu = 12;
+
+  // Target address for the relay (e.g. "127.0.0.1:443").
+  string target = 13;
+
+  // TTL for outgoing packets.
+  uint32 ttl = 14;
+
+  // Send transport: "tcp", "udp", "icmp", "icmpv6" (default: "tcp").
+  string send_transport = 15;
+
+  // Receive transport: "tcp", "udp", "icmp", "icmpv6" (default: "udp").
+  string recv_transport = 16;
+
+  // Relay address (for the relay sender, defaults to first spoof IP).
+  string relay_address = 17;
+
+  // Port the relay listens on (remote/server mode).
+  uint32 relay_port = 18;
+
+  // Client IP address (remote/server mode) — where to send responses.
+  string client_ip = 19;
+
+  // Client port (remote/server mode).
+  uint32 client_port = 20;
+
+  // Expected peer spoof IP for receive filtering (nil = accept all).
+  string peer_spoof_ip = 21;
+
+  // Source port to use in spoofed packets (default: 443).
+  uint32 spoof_port = 22;
+
+  // Pre-shared key authenticating and encrypting the tunnel. Required
+  // in both modes; must match on client and relay.
+  string auth = 23;
+
+  // Suppress kernel-generated TCP RST for the relay's listen port
+  // (Linux only; uses iptables OUTPUT REJECT rules). Prevents the kernel
+  // from answering the fake TCP handshake with RST.
+  bool suppress_rst = 24;
+
+  // Masquerade for non-tunnel traffic (probes, scanners): "http" or
+  // "tls" serve a fake web service to TCP probes, "dns" answers UDP
+  // queries. Empty or "off" disables.
+  string masquerade = 26;
+}
diff --git a/transport/internet/finalmask/rawpacket/config_register.go b/transport/internet/finalmask/rawpacket/config_register.go
new file mode 100644
index 000000000000..29f830504da1
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/config_register.go
@@ -0,0 +1,74 @@
+package rawpacket
+
+import (
+	"context"
+	stdnet "net"
+
+	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/stat"
+)
+
+const ProtocolName = "rawpacket"
+
+type rawpacketListener struct {
+	addr  stdnet.Addr
+	done  chan struct{}
+	relay *Relay
+}
+
+func (l *rawpacketListener) Close() error {
+	if l.relay != nil {
+		l.relay.Close()
+	}
+	close(l.done)
+	return nil
+}
+
+func (l *rawpacketListener) Addr() stdnet.Addr {
+	return l.addr
+}
+
+func init() {
+	common.Must(internet.RegisterProtocolConfigCreator(ProtocolName, func() interface{} {
+		return new(Config)
+	}))
+	common.Must(internet.RegisterTransportDialer(ProtocolName, Dial))
+	common.Must(internet.RegisterTransportListener(ProtocolName, listenRawpacket))
+}
+
+func listenRawpacket(ctx context.Context, address net.Address, port net.Port, settings *internet.MemoryStreamConfig, handler internet.ConnHandler) (internet.Listener, error) {
+	config := settings.ProtocolSettings.(*Config)
+	if config.Mode == "remote" {
+		cfg, err := config.buildRelayConfig()
+		if err == nil {
+			if cfg.ListenPort == 0 {
+				cfg.ListenPort = uint16(port)
+			}
+			r, err := NewRelay(cfg)
+			if err == nil {
+				go r.Run()
+				return &rawpacketListener{
+					addr:  &stdnet.TCPAddr{IP: stdnet.IP{0, 0, 0, 0}, Port: int(port)},
+					done:  make(chan struct{}),
+					relay: r,
+				}, nil
+			}
+		}
+	}
+	return &rawpacketListener{
+		addr: &stdnet.TCPAddr{IP: stdnet.IP{0, 0, 0, 0}, Port: int(port)},
+		done: make(chan struct{}),
+	}, nil
+}
+
+func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (stat.Connection, error) {
+	config := streamSettings.ProtocolSettings.(*Config)
+
+	conn, err := config.WrapConnClient(nil)
+	if err != nil {
+		return nil, err
+	}
+	return stat.Connection(conn), nil
+}
diff --git a/transport/internet/finalmask/rawpacket/conn.go b/transport/internet/finalmask/rawpacket/conn.go
new file mode 100644
index 000000000000..c4c4dde4af81
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/conn.go
@@ -0,0 +1,185 @@
+package rawpacket
+
+import (
+	"fmt"
+	"net"
+	"net/netip"
+	"strconv"
+)
+
+func (c *Config) TCP() {}
+
+func (c *Config) WrapConnClient(raw net.Conn) (net.Conn, error) {
+	if !PlatformSupported {
+		return nil, fmt.Errorf("rawpacket is not supported on this platform")
+	}
+
+	mode := c.Mode
+	if mode == "" {
+		mode = "local"
+	}
+
+	switch mode {
+	case "local":
+		return c.dialLocal()
+	case "remote":
+		return nil, fmt.Errorf("rawpacket: remote mode must be used as server")
+	default:
+		return nil, fmt.Errorf("rawpacket: unknown mode: %s", mode)
+	}
+}
+
+func (c *Config) WrapConnServer(raw net.Conn) (net.Conn, error) {
+	// The relay is owned and started by the listener (listenRawpacket);
+	// starting it here too would run two relays over the same port.
+	return raw, nil
+}
+
+func toNetIP(s string) net.IP {
+	if s == "" {
+		return nil
+	}
+	return net.ParseIP(s)
+}
+
+func toNetipAddr(s string) netip.Addr {
+	if s == "" {
+		return netip.Addr{}
+	}
+	ip, err := netip.ParseAddr(s)
+	if err != nil {
+		return netip.Addr{}
+	}
+	return ip.Unmap()
+}
+
+func (c *Config) dialLocal() (net.Conn, error) {
+	remoteIP := c.RemoteAddress
+	if remoteIP == "" {
+		return nil, fmt.Errorf("rawpacket: remoteAddress required")
+	}
+	remotePort := uint16(c.RemotePort)
+	if remotePort == 0 {
+		remotePort = 443
+	}
+
+	recvPort := uint16(c.RecvPort)
+	if recvPort == 0 {
+		recvPort = 60000
+	}
+
+	spoofIPs := c.SpoofIps
+	if len(spoofIPs) == 0 {
+		return nil, fmt.Errorf("rawpacket: at least one spoof IP required")
+	}
+
+	ttl := uint8(c.Ttl)
+	if ttl == 0 {
+		ttl = 64
+	}
+
+	sendProto := c.SendTransport
+	if sendProto == "" {
+		sendProto = "tcp"
+	}
+
+	recvProto := c.RecvTransport
+	if recvProto == "" {
+		recvProto = "udp"
+	}
+
+	relayAddrPort, err := netip.ParseAddrPort(net.JoinHostPort(remoteIP, strconv.Itoa(int(remotePort))))
+	if err != nil {
+		return nil, fmt.Errorf("rawpacket: parse remote address: %w", err)
+	}
+
+	ips, err := ParseIPs(spoofIPs)
+	if err != nil {
+		return nil, err
+	}
+
+	if c.Auth == "" {
+		return nil, fmt.Errorf("rawpacket: auth (PSK) required in local mode")
+	}
+
+	return DialSpoof(relayAddrPort, ips, recvPort, ttl, c.Mtu, sendProto, recvProto, toNetipAddr(c.PeerSpoofIp), []byte(c.Auth))
+}
+
+func (c *Config) buildRelayConfig() (*RelayConfig, error) {
+	spoofIPs := c.SpoofIps
+	if len(spoofIPs) == 0 {
+		return nil, fmt.Errorf("rawpacket: at least one spoof IP required for relay")
+	}
+	if c.Auth == "" {
+		return nil, fmt.Errorf("rawpacket: auth (PSK) required in remote mode")
+	}
+
+	target := c.Target
+	if target == "" {
+		target = "127.0.0.1:443"
+	}
+
+	relayPort := uint16(c.RelayPort)
+	if relayPort == 0 {
+		relayPort = 443
+	}
+
+	sendProto := c.SendTransport
+	if sendProto == "" {
+		sendProto = "udp"
+	}
+
+	recvProto := c.RecvTransport
+	if recvProto == "" {
+		recvProto = "tcp"
+	}
+
+	clientIP := c.ClientIp
+	clientPort := uint16(c.ClientPort)
+
+	if clientIP == "" {
+		clientIP = firstStr(spoofIPs)
+	}
+	if clientPort == 0 {
+		clientPort = uint16(c.RecvPort)
+		if clientPort == 0 {
+			clientPort = 60000
+		}
+	}
+
+	spoofPort := uint16(c.SpoofPort)
+	if spoofPort == 0 {
+		spoofPort = 443
+	}
+
+	fwdTransport := c.SendTransport
+	if fwdTransport == "udp" {
+		fwdTransport = "udp"
+	} else {
+		fwdTransport = "tcp"
+	}
+
+	return &RelayConfig{
+		ListenPort:       relayPort,
+		ForwardAddr:      target,
+		ForwardTransport: fwdTransport,
+		ClientIP:         toNetipAddr(clientIP),
+		ClientPort:       clientPort,
+		SpoofIPs:         spoofIPs,
+		SpoofPort:        spoofPort,
+		PeerSpoofIP:      toNetipAddr(c.PeerSpoofIp),
+		SendTransport:    sendProto,
+		RecvTransport:    recvProto,
+		Mtu:              c.Mtu,
+		SuppressRst:      c.SuppressRst,
+		Masquerade:       c.Masquerade,
+		Auth:             []byte(c.Auth),
+	}, nil
+}
+
+func firstStr(ss []string) string {
+	if len(ss) > 0 {
+		return ss[0]
+	}
+	return ""
+}
diff --git a/transport/internet/finalmask/rawpacket/frame.go b/transport/internet/finalmask/rawpacket/frame.go
new file mode 100644
index 000000000000..33d14ec5aff1
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/frame.go
@@ -0,0 +1,323 @@
+package rawpacket
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/binary"
+	"errors"
+	"io"
+	"sync"
+
+	"golang.org/x/crypto/hkdf"
+)
+
+// Frame layout (all integers big-endian):
+//
+//	0:4   magic (0x58445250 "XRDP")
+//	4:1   version (1)
+//	5:1   flags
+//	6:2   reserved (zero)
+//	8:16  session ID (random, chosen by the client per connection)
+//	16:4  sequence number (per direction, starting at 0)
+//	20:2  payload length
+//	22:8  nonce (seq BE || direction byte || zeros)
+//	30:   AES-256-GCM ciphertext || tag
+//
+// The header prefix (bytes 0..22) is authenticated as GCM AAD, so any
+// modification of magic/version/flags/reserved/session/seq/len is
+// detected. Direction byte in the nonce: 0 = client->relay, 1 = relay->client.
+const (
+	frameMagic     uint32 = 0x58445250
+	frameVersion   byte   = 1
+	frameHeaderLen        = 30
+	frameTagLen           = 16
+	frameNonceLen         = 8
+	frameAADLen           = 22
+	frameOverhead         = frameHeaderLen + frameTagLen
+
+	frameFlagKeepalive byte = 0x01
+	frameFlagServer    byte = 0x02
+
+	// frameMaxPayload caps each datagram so the full frame fits inside a
+	// single unfragmented packet on typical links (1400 + 46 < 1480).
+	frameMaxPayload = 1400
+)
+
+var (
+	errFrameShort  = errors.New("rawpacket: frame too short")
+	errFrameBad    = errors.New("rawpacket: invalid frame")
+	errFrameAuth   = errors.New("rawpacket: frame authentication failed")
+	errFrameReplay = errors.New("rawpacket: frame replay rejected")
+)
+
+// replayWindow is a sliding-window anti-replay filter for a single
+// direction of a session (RFC 4303 style). The window covers the highest
+// received sequence number and the replayWindowSize-1 sequence numbers
+// below it, so packets may arrive up to replayWindowSize-1 out of order.
+// Every sequence number is accepted exactly once.
+type replayWindow struct {
+	base   uint32
+	bitmap uint64
+}
+
+const replayWindowSize = 64
+
+// accept reports whether seq has not been seen before. Bit i of bitmap
+// records seq = base - (replayWindowSize - 1 - i); bit 63 is base.
+func (w *replayWindow) accept(seq uint32) bool {
+	if w.base == 0 && w.bitmap == 0 {
+		w.base = seq
+		w.bitmap = 1 << (replayWindowSize - 1)
+		return true
+	}
+	diff := int32(seq - w.base)
+	switch {
+	case diff > 0:
+		if diff < int32(replayWindowSize) {
+			// Advance: old entries shift down, new seq lands on top.
+			w.bitmap >>= uint(diff)
+			w.bitmap |= 1 << (replayWindowSize - 1)
+		} else {
+			// Jump: the whole old window is discarded.
+			w.bitmap = 1 << (replayWindowSize - 1)
+		}
+		w.base = seq
+		return true
+	case diff < 0:
+		offset := int32(replayWindowSize) - 1 + diff
+		if offset < 0 {
+			return false
+		}
+		bit := uint64(1) << uint(offset)
+		if w.bitmap&bit != 0 {
+			return false
+		}
+		w.bitmap |= bit
+		return true
+	default:
+		// seq == base: duplicate unless the top bit is somehow clear.
+		if w.bitmap&(1<<(replayWindowSize-1)) != 0 {
+			return false
+		}
+		w.bitmap |= 1 << (replayWindowSize - 1)
+		return true
+	}
+}
+
+// frameCrypto owns the per-session keys and per-direction sequence/replay
+// state. One instance exists per session on each side. The two directions
+// have independent mutexes so uplink and downlink never contend.
+type frameCrypto struct {
+	sid        [8]byte
+	clientAEAD cipher.AEAD
+	serverAEAD cipher.AEAD
+
+	clientSeq uint32
+	serverSeq uint32
+	clientRep replayWindow
+	serverRep replayWindow
+
+	clientMu sync.Mutex
+	serverMu sync.Mutex
+}
+
+func newFrameCrypto(psk []byte, sid [8]byte) (*frameCrypto, error) {
+	clientKey, err := deriveFrameKey(psk, sid, []byte("rawpacket-client-v1"))
+	if err != nil {
+		return nil, err
+	}
+	serverKey, err := deriveFrameKey(psk, sid, []byte("rawpacket-server-v1"))
+	if err != nil {
+		return nil, err
+	}
+	clientAEAD, err := newGCM(clientKey)
+	if err != nil {
+		return nil, err
+	}
+	serverAEAD, err := newGCM(serverKey)
+	if err != nil {
+		return nil, err
+	}
+	return &frameCrypto{
+		sid:        sid,
+		clientAEAD: clientAEAD,
+		serverAEAD: serverAEAD,
+	}, nil
+}
+
+func deriveFrameKey(psk []byte, sid [8]byte, info []byte) ([]byte, error) {
+	key := make([]byte, 32)
+	r := hkdf.New(sha256.New, psk, sid[:], info)
+	if _, err := io.ReadFull(r, key); err != nil {
+		return nil, err
+	}
+	return key, nil
+}
+
+func newGCM(key []byte) (cipher.AEAD, error) {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	return cipher.NewGCMWithNonceSize(block, frameNonceLen)
+}
+
+func newSessionID() ([8]byte, error) {
+	var sid [8]byte
+	if _, err := rand.Read(sid[:]); err != nil {
+		return sid, err
+	}
+	return sid, nil
+}
+
+func frameNonce(seq uint32, server bool) [frameNonceLen]byte {
+	var n [frameNonceLen]byte
+	binary.BigEndian.PutUint32(n[0:4], seq)
+	if server {
+		n[4] = 1
+	}
+	return n
+}
+
+// seal builds and encrypts one frame from payload. server selects the
+// relay->client direction. The sequence counter and replay window are
+// updated. Payload is capped at frameMaxPayload.
+func (f *frameCrypto) seal(server bool, payload []byte, keepalive bool) ([]byte, error) {
+	if len(payload) > frameMaxPayload {
+		return nil, errors.New("rawpacket: payload exceeds frameMaxPayload")
+	}
+	if server {
+		f.serverMu.Lock()
+		defer f.serverMu.Unlock()
+	} else {
+		f.clientMu.Lock()
+		defer f.clientMu.Unlock()
+	}
+
+	seq := f.clientSeq
+	var aead cipher.AEAD
+	if server {
+		seq = f.serverSeq
+		f.serverSeq++
+		aead = f.serverAEAD
+	} else {
+		seq = f.clientSeq
+		f.clientSeq++
+		aead = f.clientAEAD
+	}
+
+	flags := byte(0)
+	if server {
+		flags |= frameFlagServer
+	}
+	if keepalive {
+		flags |= frameFlagKeepalive
+	}
+
+	out := make([]byte, frameHeaderLen+len(payload)+frameTagLen)
+	binary.BigEndian.PutUint32(out[0:4], frameMagic)
+	out[4] = frameVersion
+	out[5] = flags
+	// 6:7 reserved
+	copy(out[8:16], f.sid[:])
+	binary.BigEndian.PutUint32(out[16:20], seq)
+	binary.BigEndian.PutUint16(out[20:22], uint16(len(payload)))
+
+	nonce := frameNonce(seq, server)
+	aead.Seal(out[frameHeaderLen:frameHeaderLen], nonce[:], payload, out[:frameAADLen])
+	return out, nil
+}
+
+// open parses, authenticates and decrypts one frame. server selects the
+// direction the frame is expected from. The returned payload is freshly
+// allocated and safe to retain.
+func (f *frameCrypto) open(b []byte, server bool) (payload []byte, flags byte, err error) {
+	if len(b) < frameHeaderLen+frameTagLen {
+		return nil, 0, errFrameShort
+	}
+	if binary.BigEndian.Uint32(b[0:4]) != frameMagic || b[4] != frameVersion {
+		return nil, 0, errFrameBad
+	}
+	flags = b[5]
+	if (flags&frameFlagServer != 0) != server {
+		return nil, 0, errFrameBad
+	}
+	pLen := int(binary.BigEndian.Uint16(b[20:22]))
+	if pLen != len(b)-frameHeaderLen-frameTagLen {
+		return nil, 0, errFrameBad
+	}
+	seq := binary.BigEndian.Uint32(b[16:20])
+
+	if server {
+		f.serverMu.Lock()
+		defer f.serverMu.Unlock()
+	} else {
+		f.clientMu.Lock()
+		defer f.clientMu.Unlock()
+	}
+
+	var aead cipher.AEAD
+	var rep *replayWindow
+	if server {
+		aead = f.serverAEAD
+		rep = &f.serverRep
+	} else {
+		aead = f.clientAEAD
+		rep = &f.clientRep
+	}
+	if !rep.accept(seq) {
+		return nil, 0, errFrameReplay
+	}
+	nonce := frameNonce(seq, server)
+	ct := b[frameHeaderLen : frameHeaderLen+pLen+frameTagLen]
+	pt, err := aead.Open(nil, nonce[:], ct, b[:frameAADLen])
+	if err != nil {
+		return nil, 0, errFrameAuth
+	}
+	return pt, flags, nil
+}
+
+// frameSessionID extracts the session ID from a frame header without
+// decrypting it. Returns false for non-frame traffic (which the relay must
+// silently ignore: real TLS, kernel noise, etc.).
+func frameSessionID(b []byte) (sid [8]byte, ok bool) {
+	if len(b) < frameHeaderLen {
+		return sid, false
+	}
+	if binary.BigEndian.Uint32(b[0:4]) != frameMagic || b[4] != frameVersion {
+		return sid, false
+	}
+	copy(sid[:], b[8:16])
+	return sid, true
+}
+
+// sealSplit splits a large payload into frames of at most maxPayload and
+// seals each one in sequence order.
+func (f *frameCrypto) sealSplit(server bool, payload []byte, maxPayload int, keepalive bool) ([][]byte, error) {
+	if maxPayload <= 0 {
+		maxPayload = frameMaxPayload
+	}
+	if len(payload) == 0 {
+		frame, err := f.seal(server, nil, keepalive)
+		if err != nil {
+			return nil, err
+		}
+		return [][]byte{frame}, nil
+	}
+	frames := make([][]byte, 0, (len(payload)+maxPayload-1)/maxPayload)
+	for len(payload) > 0 {
+		chunk := payload
+		if len(chunk) > maxPayload {
+			chunk = chunk[:maxPayload]
+		}
+		frame, err := f.seal(server, chunk, false)
+		if err != nil {
+			return nil, err
+		}
+		frames = append(frames, frame)
+		payload = payload[len(chunk):]
+	}
+	return frames, nil
+}
diff --git a/transport/internet/finalmask/rawpacket/frame_demux.go b/transport/internet/finalmask/rawpacket/frame_demux.go
new file mode 100644
index 000000000000..0ec2ebd1bd3b
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/frame_demux.go
@@ -0,0 +1,141 @@
+package rawpacket
+
+import (
+	"net/netip"
+	"sync"
+)
+
+// frameDemux demultiplexes decrypted relay->client frames to per-conn
+// consumers. Multiple SpoofConns on the same host share one raw receiver
+// per (protocol, listen port); a raw socket delivers a copy of every
+// matching packet to every socket, so the receiver must be shared or
+// frames would be duplicated across connections.
+type frameDemux struct {
+	proto  string
+	port   uint16
+	peerIP netip.Addr
+
+	mu       sync.Mutex
+	sessions map[[8]byte]*demuxSession
+	recver   SpoofReceiver
+	refs     int
+	running  bool
+	gen      uint64
+}
+
+type demuxSession struct {
+	crypto *frameCrypto
+	ch     chan demuxData
+}
+
+// demuxData is one decrypted relay->client payload with the originating
+// TCP header metadata (for sequence/ack state tracking).
+type demuxData struct {
+	payload []byte
+	tcp     *TCPMeta
+}
+
+type demuxKey struct {
+	proto string
+	port  uint16
+}
+
+var demuxRegistry sync.Map // demuxKey -> *frameDemux
+
+func getFrameDemux(proto string, port uint16, peerIP netip.Addr) *frameDemux {
+	key := demuxKey{proto: proto, port: port}
+	if d, ok := demuxRegistry.Load(key); ok {
+		return d.(*frameDemux)
+	}
+	d := &frameDemux{
+		proto:    proto,
+		port:     port,
+		peerIP:   peerIP,
+		sessions: make(map[[8]byte]*demuxSession),
+	}
+	actual, _ := demuxRegistry.LoadOrStore(key, d)
+	return actual.(*frameDemux)
+}
+
+// register subscribes sid to the demux, starting the shared receiver and
+// demux goroutine on first use.
+func (d *frameDemux) register(sid [8]byte, crypto *frameCrypto, ch chan demuxData) error {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	d.sessions[sid] = &demuxSession{crypto: crypto, ch: ch}
+	d.refs++
+	if d.running {
+		return nil
+	}
+	recver, err := NewReceiver(d.proto, &SpoofReceiverConfig{
+		ListenPort:  d.port,
+		PeerSpoofIP: d.peerIP,
+		BufferSize:  4 * 1024 * 1024,
+	})
+	if err != nil {
+		delete(d.sessions, sid)
+		d.refs--
+		return err
+	}
+	d.recver = recver
+	d.running = true
+	d.gen++
+	go d.run(d.gen)
+	return nil
+}
+
+func (d *frameDemux) unregister(sid [8]byte) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	delete(d.sessions, sid)
+	d.refs--
+	if d.refs > 0 || !d.running {
+		return
+	}
+	d.running = false
+	d.recver.Close()
+	d.recver = nil
+	demuxRegistry.Delete(demuxKey{proto: d.proto, port: d.port})
+}
+
+func (d *frameDemux) run(gen uint64) {
+	for {
+		pkt, _, _, tcp, err := d.recver.Receive()
+		if err != nil {
+			d.mu.Lock()
+			if d.gen != gen {
+				// Superseded by a newer generation (the demux was torn
+				// down and restarted): leave the new sessions alone.
+				d.mu.Unlock()
+				return
+			}
+			// Receiver died unexpectedly (or the demux was torn down):
+			// unblock every consumer.
+			for _, s := range d.sessions {
+				close(s.ch)
+			}
+			d.sessions = make(map[[8]byte]*demuxSession)
+			d.running = false
+			d.mu.Unlock()
+			return
+		}
+		sid, ok := frameSessionID(pkt)
+		if !ok {
+			continue
+		}
+		d.mu.Lock()
+		s := d.sessions[sid]
+		d.mu.Unlock()
+		if s == nil {
+			continue
+		}
+		payload, flags, err := s.crypto.open(pkt, true)
+		if err != nil || flags&frameFlagKeepalive != 0 || len(payload) == 0 {
+			continue
+		}
+		select {
+		case s.ch <- demuxData{payload: payload, tcp: tcp}:
+		default: // consumer is slow: drop rather than stall the demux
+		}
+	}
+}
diff --git a/transport/internet/finalmask/rawpacket/frame_test.go b/transport/internet/finalmask/rawpacket/frame_test.go
new file mode 100644
index 000000000000..84c5c2279758
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/frame_test.go
@@ -0,0 +1,283 @@
+package rawpacket
+
+import (
+	"bytes"
+	"crypto/rand"
+	"testing"
+)
+
+func testFrameCrypto(t *testing.T) *frameCrypto {
+	t.Helper()
+	psk := []byte("test-psk-secret")
+	var sid [8]byte
+	if _, err := rand.Read(sid[:]); err != nil {
+		t.Fatal(err)
+	}
+	f, err := newFrameCrypto(psk, sid)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return f
+}
+
+func TestFrameSealOpenRoundTrip(t *testing.T) {
+	f := testFrameCrypto(t)
+	payload := []byte("hello rawpacket")
+
+	frame, err := f.seal(false, payload, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got, flags, err := f.open(frame, false)
+	if err != nil {
+		t.Fatalf("open: %v", err)
+	}
+	if !bytes.Equal(got, payload) {
+		t.Fatalf("payload mismatch: got %q", got)
+	}
+	if flags&frameFlagServer != 0 {
+		t.Fatal("client frame must not carry server flag")
+	}
+
+	frame, err = f.seal(true, payload, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got, flags, err = f.open(frame, true)
+	if err != nil {
+		t.Fatalf("open server frame: %v", err)
+	}
+	if !bytes.Equal(got, payload) {
+		t.Fatalf("payload mismatch: got %q", got)
+	}
+	if flags&frameFlagKeepalive == 0 || flags&frameFlagServer == 0 {
+		t.Fatalf("expected keepalive+server flags, got %#x", flags)
+	}
+}
+
+func TestFrameDirectionEnforced(t *testing.T) {
+	f := testFrameCrypto(t)
+	frame, err := f.seal(false, []byte("up"), false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, _, err := f.open(frame, true); err == nil {
+		t.Fatal("opening a client frame as server frame must fail")
+	}
+}
+
+func TestFrameTamperDetection(t *testing.T) {
+	f := testFrameCrypto(t)
+	frame, err := f.seal(false, []byte("authenticated"), false)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Tamper every header byte region: magic, version, flags, session,
+	// seq, payload length.
+	flips := []int{0, 3, 4, 5, 8, 15, 16, 19, 20, 21}
+	for _, i := range flips {
+		bad := make([]byte, len(frame))
+		copy(bad, frame)
+		bad[i] ^= 0xFF
+		if _, _, err := f.open(bad, false); err == nil {
+			t.Fatalf("tampered byte %d was accepted", i)
+		}
+	}
+
+	// Flip a payload byte (after the AAD region).
+	bad := make([]byte, len(frame))
+	copy(bad, frame)
+	bad[len(bad)-1] ^= 0xFF
+	if _, _, err := f.open(bad, false); err == nil {
+		t.Fatal("tampered payload was accepted")
+	}
+
+	// A truncated frame must be rejected.
+	if _, _, err := f.open(frame[:len(frame)-1], false); err == nil {
+		t.Fatal("truncated frame was accepted")
+	}
+}
+
+func TestFrameReplayProtection(t *testing.T) {
+	f := testFrameCrypto(t)
+
+	frame, err := f.seal(false, []byte("one"), false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, _, err := f.open(frame, false); err != nil {
+		t.Fatalf("first open: %v", err)
+	}
+	// Replaying the exact same frame must be rejected.
+	if _, _, err := f.open(frame, false); err == nil {
+		t.Fatal("replayed frame was accepted")
+	}
+	// Same seq, different ciphertext (attacker re-encrypt guess) must fail.
+	if _, _, err := f.open(frame, false); err == nil {
+		t.Fatal("replayed frame accepted twice")
+	}
+}
+
+func TestFrameReorderingWithinWindow(t *testing.T) {
+	f := testFrameCrypto(t)
+
+	var frames [][]byte
+	for i := 0; i < 10; i++ {
+		fr, err := f.seal(false, []byte{byte(i)}, false)
+		if err != nil {
+			t.Fatal(err)
+		}
+		frames = append(frames, fr)
+	}
+	// Deliver 0..9 in scrambled order: all must be accepted exactly once.
+	order := []int{2, 0, 1, 5, 3, 4, 9, 6, 7, 8}
+	for _, i := range order {
+		if _, _, err := f.open(frames[i], false); err != nil {
+			t.Fatalf("frame %d out of order rejected: %v", i, err)
+		}
+	}
+	// All frames are now consumed; resending any must be rejected.
+	for i := 0; i < 10; i++ {
+		if _, _, err := f.open(frames[i], false); err == nil {
+			t.Fatalf("replayed frame %d accepted", i)
+		}
+	}
+}
+
+func TestFrameSeqJumpAdvance(t *testing.T) {
+	f := testFrameCrypto(t)
+	var first []byte
+	for i := 0; i < 70; i++ {
+		fr, err := f.seal(false, []byte{byte(i)}, false)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if i == 0 {
+			first = fr
+		}
+		if _, _, err := f.open(fr, false); err != nil {
+			t.Fatalf("frame %d: %v", i, err)
+		}
+	}
+	// The window has advanced past seq 0 (base=69); replaying it must fail.
+	if _, _, err := f.open(first, false); err == nil {
+		t.Fatal("stale frame accepted after window advance")
+	}
+}
+
+func TestFrameKeepaliveFlag(t *testing.T) {
+	f := testFrameCrypto(t)
+	frame, err := f.seal(false, nil, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	payload, flags, err := f.open(frame, false)
+	if err != nil {
+		t.Fatalf("open: %v", err)
+	}
+	if len(payload) != 0 {
+		t.Fatalf("keepalive payload must be empty, got %d bytes", len(payload))
+	}
+	if flags&frameFlagKeepalive == 0 {
+		t.Fatal("keepalive flag not set")
+	}
+}
+
+func TestFrameWrongKeyRejected(t *testing.T) {
+	a := testFrameCrypto(t)
+	b, err := newFrameCrypto([]byte("other-psk"), a.sid)
+	if err != nil {
+		t.Fatal(err)
+	}
+	frame, err := a.seal(false, []byte("secret"), false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, _, err := b.open(frame, false); err == nil {
+		t.Fatal("frame sealed with a different PSK was accepted")
+	}
+}
+
+func TestSealSplit(t *testing.T) {
+	f := testFrameCrypto(t)
+	payload := bytes.Repeat([]byte("x"), frameMaxPayload*3+7)
+
+	frames, err := f.sealSplit(false, payload, 0, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(frames) != 4 {
+		t.Fatalf("expected 4 frames, got %d", len(frames))
+	}
+	var got []byte
+	for _, fr := range frames {
+		pt, _, err := f.open(fr, false)
+		if err != nil {
+			t.Fatalf("open: %v", err)
+		}
+		got = append(got, pt...)
+	}
+	if !bytes.Equal(got, payload) {
+		t.Fatal("split payload mismatch")
+	}
+
+	// Empty payload produces a single empty frame.
+	frames, err = f.sealSplit(false, nil, 0, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(frames) != 1 {
+		t.Fatalf("expected 1 frame for empty payload, got %d", len(frames))
+	}
+}
+
+func TestReplayWindow(t *testing.T) {
+	var w replayWindow
+	if !w.accept(100) {
+		t.Fatal("first seq must be accepted")
+	}
+	if w.accept(100) {
+		t.Fatal("duplicate must be rejected")
+	}
+	if !w.accept(101) {
+		t.Fatal("next seq must be accepted")
+	}
+	// seq 99 is below the max but still inside the window and unseen:
+	// tolerated reordering.
+	if !w.accept(99) {
+		t.Fatal("in-window reordering must be accepted")
+	}
+	if w.accept(99) {
+		t.Fatal("duplicate in-window seq must be rejected")
+	}
+	if !w.accept(160) {
+		t.Fatal("seq jump must be accepted")
+	}
+	// seq 99 is now outside the window (base=160, window floor=97).
+	if w.accept(99) {
+		t.Fatal("seq below window floor must be rejected")
+	}
+	if w.accept(160) {
+		t.Fatal("duplicate after jump must be rejected")
+	}
+}
+
+func TestFrameSessionID(t *testing.T) {
+	f := testFrameCrypto(t)
+	frame, err := f.seal(false, []byte("x"), false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	sid, ok := frameSessionID(frame)
+	if !ok {
+		t.Fatal("frameSessionID failed on valid frame")
+	}
+	if sid != f.sid {
+		t.Fatal("session id mismatch")
+	}
+	// Non-frame traffic (e.g. a real TLS ClientHello) must not parse.
+	if _, ok := frameSessionID([]byte("not a frame")); ok {
+		t.Fatal("garbage accepted as frame")
+	}
+}
diff --git a/transport/internet/finalmask/rawpacket/masquerade.go b/transport/internet/finalmask/rawpacket/masquerade.go
new file mode 100644
index 000000000000..4d3c497787d5
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/masquerade.go
@@ -0,0 +1,405 @@
+package rawpacket
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/binary"
+	"log"
+	"math/big"
+	"net/netip"
+	"strings"
+	"sync"
+	"time"
+)
+
+// masquerade answers probes that do not speak the tunnel protocol, so the
+// relay port looks like a real service:
+//
+//	http/tls:  fake TCP handshake, then serve a static HTTP page or a
+//	           TLS ServerHello + certificate flow
+//	dns:       answer UDP queries with a DNS reply (A record for type A,
+//	           NXDOMAIN otherwise), using the relay's own address
+//
+// Replies are sent from the address the probe dialed (dst of the
+// incoming packet), never from the tunnel's spoofed source IPs.
+
+type masqueradeMode int
+
+const (
+	masqOff masqueradeMode = iota
+	masqHTTP
+	masqTLS
+	masqDNS
+
+	masqFlowTTL     = 2 * time.Minute
+	masqFlowCap     = 4096
+	masqMaxChunkLen = 1400
+)
+
+func parseMasqueradeMode(s string) masqueradeMode {
+	switch strings.ToLower(strings.TrimSpace(s)) {
+	case "http":
+		return masqHTTP
+	case "tls", "https":
+		return masqTLS
+	case "dns":
+		return masqDNS
+	default:
+		return masqOff
+	}
+}
+
+func (m masqueradeMode) String() string {
+	switch m {
+	case masqHTTP:
+		return "http"
+	case masqTLS:
+		return "tls"
+	case masqDNS:
+		return "dns"
+	default:
+		return "off"
+	}
+}
+
+type masqKey struct {
+	ip   netip.Addr
+	port uint16
+}
+
+type fakeFlow struct {
+	tcp      *TCPSimState
+	resp     []byte
+	sent     int
+	lastSeen time.Time
+}
+
+type masquerade struct {
+	mode   masqueradeMode
+	fd     *rawSendFD
+	relayP uint16 // relay listen port, source port of replies
+
+	mu    sync.Mutex
+	flows map[masqKey]*fakeFlow
+	ipID  uint16
+	idMu  sync.Mutex
+
+	httpResp []byte
+	tlsResp  []byte
+
+	done chan struct{}
+}
+
+// newMasquerade builds the responder for mode; mode ""/"off" returns nil.
+func newMasquerade(mode string, relayPort uint16) (*masquerade, error) {
+	m := parseMasqueradeMode(mode)
+	if m == masqOff {
+		return nil, nil
+	}
+	fd, err := openRawSenderAny()
+	if err != nil {
+		return nil, err
+	}
+	resp, err := masqueradeResponses(m)
+	if err != nil {
+		fd.close()
+		return nil, err
+	}
+	mg := &masquerade{
+		mode:     m,
+		fd:       fd,
+		relayP:   relayPort,
+		flows:    make(map[masqKey]*fakeFlow),
+		httpResp: resp,
+		tlsResp:  resp,
+		done:     make(chan struct{}),
+	}
+	go mg.gcLoop()
+	log.Printf("[rawpacket] masquerade enabled: %s (port %d)", m, relayPort)
+	return mg, nil
+}
+
+// masqueradeResponses builds the static response payload for the mode.
+func masqueradeResponses(m masqueradeMode) ([]byte, error) {
+	switch m {
+	case masqHTTP:
+		return fakeHTTPResponse(), nil
+	case masqTLS:
+		return buildFakeTLSServer()
+	default:
+		return nil, nil
+	}
+}
+
+func (m *masquerade) close() {
+	if m == nil {
+		return
+	}
+	close(m.done)
+	m.fd.close()
+}
+
+func (m *masquerade) nextIPID() uint16 {
+	m.idMu.Lock()
+	defer m.idMu.Unlock()
+	m.ipID++
+	return m.ipID
+}
+
+// onTCPSYN handles a bare SYN from a probe: answer SYN|ACK and start a
+// fake flow so subsequent data can be served.
+func (m *masquerade) onTCPSYN(relayIP netip.Addr, relayPort uint16, probeIP netip.Addr, probePort uint16, seq uint32) {
+	if m == nil || (m.mode != masqHTTP && m.mode != masqTLS) {
+		return
+	}
+	key := masqKey{probeIP, probePort}
+	m.mu.Lock()
+	f := m.flows[key]
+	if f == nil {
+		resp := m.httpResp
+		if m.mode == masqTLS {
+			resp = m.tlsResp
+		}
+		f = &fakeFlow{tcp: newTCPSimState(), resp: resp}
+		if len(m.flows) < masqFlowCap {
+			m.flows[key] = f
+		}
+	}
+	f.lastSeen = time.Now()
+	f.tcp.observeClientSeq(seq, 0)
+	m.mu.Unlock()
+	m.sendTCP(relayIP, relayPort, probeIP, probePort, f, nil, true)
+}
+
+// onTCPData serves the fake response to probe data. The response is
+// streamed in MSS-sized chunks and repeats once exhausted, so repeated
+// requests (e.g. a browser reloading) keep getting answers.
+func (m *masquerade) onTCPData(relayIP netip.Addr, relayPort uint16, probeIP netip.Addr, probePort uint16, seq uint32, payload []byte) {
+	if m == nil || (m.mode != masqHTTP && m.mode != masqTLS) || len(payload) == 0 {
+		return
+	}
+	key := masqKey{probeIP, probePort}
+	m.mu.Lock()
+	f := m.flows[key]
+	if f == nil {
+		m.mu.Unlock()
+		return
+	}
+	f.lastSeen = time.Now()
+	f.tcp.observeClientSeq(seq, len(payload))
+	chunk := f.resp[f.sent:]
+	if len(chunk) > masqMaxChunkLen {
+		chunk = chunk[:masqMaxChunkLen]
+	}
+	f.sent += len(chunk)
+	if f.sent >= len(f.resp) {
+		f.sent = 0
+	}
+	m.mu.Unlock()
+	m.sendTCP(relayIP, relayPort, probeIP, probePort, f, chunk, false)
+}
+
+func (m *masquerade) sendTCP(relayIP netip.Addr, relayPort uint16, probeIP netip.Addr, probePort uint16, f *fakeFlow, payload []byte, syn bool) {
+	var flags uint8
+	if syn {
+		flags = TCPFlagSyn | TCPFlagAck
+	} else {
+		flags = TCPFlagAck
+	}
+	seq := f.tcp.nextSeq(len(payload))
+	pkt := BuildTCPPacket(relayIP, probeIP, relayPort, probePort, seq, f.tcp.ack(), flags, payload, 64, m.nextIPID(), false)
+	_ = m.fd.sendTo(pkt, probeIP)
+}
+
+// onUDP answers a probe datagram with a fake DNS reply.
+func (m *masquerade) onUDP(relayIP netip.Addr, relayPort uint16, probeIP netip.Addr, probePort uint16, payload []byte) {
+	if m == nil || m.mode != masqDNS || len(payload) < 12 {
+		return
+	}
+	reply := fakeDNSReply(payload, relayIP)
+	if len(reply) == 0 {
+		return
+	}
+	pkt := BuildRawUDP(relayIP, probeIP, relayPort, probePort, reply, 64, m.nextIPID())
+	_ = m.fd.sendTo(pkt, probeIP)
+}
+
+// gcLoop drops stale fake flows.
+func (m *masquerade) gcLoop() {
+	t := time.NewTicker(30 * time.Second)
+	defer t.Stop()
+	for {
+		select {
+		case <-m.done:
+			return
+		case <-t.C:
+			now := time.Now()
+			m.mu.Lock()
+			for k, f := range m.flows {
+				if now.Sub(f.lastSeen) > masqFlowTTL {
+					delete(m.flows, k)
+				}
+			}
+			m.mu.Unlock()
+		}
+	}
+}
+
+// fakeHTTPResponse is a minimal nginx-style page.
+func fakeHTTPResponse() []byte {
+	body := "<html>\r\n<head><title>Welcome to nginx!</title></head>\r\n<body>\r\n<h1>Welcome to nginx!</h1>\r\n</body>\r\n</html>\r\n"
+	hdr := "HTTP/1.1 200 OK\r\nServer: nginx\r\nContent-Type: text/html\r\nContent-Length: " + itoa(len(body)) + "\r\nConnection: close\r\n\r\n"
+	return append([]byte(hdr), body...)
+}
+
+func itoa(n int) string {
+	if n == 0 {
+		return "0"
+	}
+	var b [16]byte
+	i := len(b)
+	for n > 0 {
+		i--
+		b[i] = byte('0' + n%10)
+		n /= 10
+	}
+	return string(b[i:])
+}
+
+// buildFakeTLSServer produces a canned TLS 1.2 ServerHello + Certificate +
+// ServerHelloDone record flow backed by a self-signed ECDSA certificate.
+// The handshake never completes (no key exchange), which is enough for
+// passive DPI classification and port scanners.
+func buildFakeTLSServer() ([]byte, error) {
+	key, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	if err != nil {
+		return nil, err
+	}
+	tmpl := &x509.Certificate{
+		SerialNumber: big.NewInt(1),
+		Subject:      pkix.Name{CommonName: "nginx", Organization: []string{"nginx"}},
+		NotBefore:    time.Now().Add(-24 * time.Hour),
+		NotAfter:     time.Now().Add(365 * 24 * time.Hour),
+		KeyUsage:     x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:  []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+	}
+	der, err := x509.CreateCertificate(rand.Reader, tmpl, tmpl, &key.PublicKey, key)
+	if err != nil {
+		return nil, err
+	}
+
+	var random [32]byte
+	_, _ = rand.Read(random[:])
+
+	// ServerHello (TLS 1.2, ECDHE_ECDSA_WITH_AES_128_GCM_SHA256)
+	sh := make([]byte, 0, 38+32)
+	sh = append(sh, 0x03, 0x03)
+	sh = append(sh, random[:]...)
+	sh = append(sh, 0x20)
+	sh = append(sh, random[:32]...)
+	sh = append(sh, 0xC0, 0x2B, 0x00)
+
+	// handshake wrapper: type + 24-bit length
+	hello := tlsHandshakeRecord(0x02, sh)
+
+	// Certificate
+	certMsg := make([]byte, 0, 3+len(der))
+	certMsg = binary.BigEndian.AppendUint32(certMsg, uint32(len(der)))[1:]
+	certMsg = append(certMsg, der...)
+	cert := tlsHandshakeRecord(0x0B, certMsg)
+
+	// ServerHelloDone
+	done := tlsHandshakeRecord(0x0E, nil)
+
+	var out []byte
+	out = append(out, hello...)
+	out = append(out, cert...)
+	out = append(out, done...)
+	return out, nil
+}
+
+// tlsHandshakeRecord wraps a handshake message in a TLS record (content
+// type 0x16) with a 24-bit handshake length header.
+func tlsHandshakeRecord(msgType byte, body []byte) []byte {
+	out := make([]byte, 0, 5+4+len(body))
+	out = append(out, 0x16, 0x03, 0x03)
+	l := 4 + len(body)
+	out = append(out, byte(l>>8), byte(l))
+	out = append(out, msgType)
+	out = append(out, byte(len(body)>>16), byte(len(body)>>8), byte(len(body)))
+	out = append(out, body...)
+	return out
+}
+
+// fakeDNSReply builds a DNS reply for query: an A record with the relay's
+// address for type A queries, NXDOMAIN otherwise. Malformed queries yield
+// nil (no reply). The question is always echoed.
+func fakeDNSReply(query []byte, relayIP netip.Addr) []byte {
+	if len(query) < 12 {
+		return nil
+	}
+	id := query[0:2]
+	flags := binary.BigEndian.Uint16(query[2:4])
+	qd := binary.BigEndian.Uint16(query[4:6])
+	if qd == 0 {
+		return nil
+	}
+	off := 12
+	qnameEnd := -1
+	for off < len(query) {
+		l := int(query[off])
+		if l == 0 {
+			off++
+			qnameEnd = off
+			break
+		}
+		if l&0xC0 == 0xC0 { // compression pointer: name ends at 2-byte pointer
+			off += 2
+			qnameEnd = off
+			break
+		}
+		if off+1+l > len(query) {
+			return nil
+		}
+		off += 1 + l
+		if off-12 > 255 {
+			return nil
+		}
+	}
+	if qnameEnd < 0 || off+4 > len(query) {
+		return nil
+	}
+	qtype := binary.BigEndian.Uint16(query[off:])
+	qclass := binary.BigEndian.Uint16(query[off+2:])
+
+	// QR=1, opcode echoed, RD echoed, RA=1; rcode 3 (NXDOMAIN) unless we
+	// answer the query.
+	rcode := uint16(3)
+	ancount := uint16(0)
+	var answer []byte
+	if qtype == 1 && qclass == 1 && relayIP.Is4() { // A query
+		rcode = 0
+		ancount = 1
+		answer = make([]byte, 0, 16)
+		answer = append(answer, 0xC0, 0x0C)                // name pointer to question
+		answer = binary.BigEndian.AppendUint16(answer, 1)  // type A
+		answer = binary.BigEndian.AppendUint16(answer, 1)  // class IN
+		answer = binary.BigEndian.AppendUint32(answer, 60) // TTL
+		answer = binary.BigEndian.AppendUint16(answer, 4)  // rdlength
+		answer = append(answer, relayIP.AsSlice()...)
+	}
+
+	reply := make([]byte, 0, len(query)+16)
+	reply = append(reply, id...)
+	reply = binary.BigEndian.AppendUint16(reply, 0x8000|(flags&0x7800)|0x0080|rcode)
+	reply = binary.BigEndian.AppendUint16(reply, 1) // QDCOUNT
+	reply = binary.BigEndian.AppendUint16(reply, ancount)
+	reply = binary.BigEndian.AppendUint16(reply, 0) // NS
+	reply = binary.BigEndian.AppendUint16(reply, 0) // AR
+	reply = append(reply, query[12:off+4]...)       // question: qname + type + class
+	reply = append(reply, answer...)
+	return reply
+}
diff --git a/transport/internet/finalmask/rawpacket/masquerade_test.go b/transport/internet/finalmask/rawpacket/masquerade_test.go
new file mode 100644
index 000000000000..42d233280377
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/masquerade_test.go
@@ -0,0 +1,301 @@
+package rawpacket
+
+import (
+	"encoding/binary"
+	"net/netip"
+	"testing"
+)
+
+func TestParseMasqueradeMode(t *testing.T) {
+	cases := map[string]masqueradeMode{
+		"":      masqOff,
+		"off":   masqOff,
+		"http":  masqHTTP,
+		"tls":   masqTLS,
+		"https": masqTLS,
+		"dns":   masqDNS,
+		"HTTP":  masqHTTP,
+	}
+	for in, want := range cases {
+		if got := parseMasqueradeMode(in); got != want {
+			t.Fatalf("parseMasqueradeMode(%q) = %v, want %v", in, got, want)
+		}
+	}
+}
+
+func TestFakeHTTPResponse(t *testing.T) {
+	resp := fakeHTTPResponse()
+	if len(resp) == 0 {
+		t.Fatal("empty HTTP response")
+	}
+	s := string(resp)
+	if !startsWith(s, "HTTP/1.1 200 OK\r\n") {
+		t.Fatalf("missing status line: %q", s[:32])
+	}
+	// Content-Length must match the body length
+	body := "<html>\r\n<head><title>Welcome to nginx!</title></head>\r\n<body>\r\n<h1>Welcome to nginx!</h1>\r\n</body>\r\n</html>\r\n"
+	cl := "Content-Length: " + itoa(len(body))
+	if !contains(s, cl) {
+		t.Fatalf("missing %q in %q", cl, s[:120])
+	}
+}
+
+func TestBuildFakeTLSServer(t *testing.T) {
+	resp, err := buildFakeTLSServer()
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Expect 3 TLS records: ServerHello, Certificate, ServerHelloDone
+	var off int
+	var types []byte
+	var lens []int
+	for off < len(resp) && len(types) < 3 {
+		if off+5 > len(resp) || resp[off] != 0x16 {
+			t.Fatalf("bad record header at %d: %x", off, resp[off:])
+		}
+		l := int(resp[off+3])<<8 | int(resp[off+4])
+		if off+5+l > len(resp) {
+			t.Fatalf("record overruns buffer at %d", off)
+		}
+		types = append(types, resp[off+5])
+		lens = append(lens, l)
+		off += 5 + l
+	}
+	if off != len(resp) {
+		t.Fatalf("trailing bytes after 3 records: %d", len(resp)-off)
+	}
+	if types[0] != 0x02 || types[1] != 0x0B || types[2] != 0x0E {
+		t.Fatalf("record types = %x, want [2 b e]", types)
+	}
+	// Certificate record must contain a DER cert
+	if lens[1] < 4 {
+		t.Fatalf("certificate record too small: %d", lens[1])
+	}
+}
+
+func TestFakeDNSReplyA(t *testing.T) {
+	// build a DNS A query for example.com
+	q := buildDNSQuery("example.com", 1, 0x1234, 0x0100)
+	relay := netip.MustParseAddr("203.0.113.9")
+	reply := fakeDNSReply(q, relay)
+	if reply == nil {
+		t.Fatal("nil reply for A query")
+	}
+	if binary.BigEndian.Uint16(reply[0:2]) != 0x1234 {
+		t.Fatalf("bad ID")
+	}
+	flags := binary.BigEndian.Uint16(reply[2:4])
+	if flags&0x8000 == 0 {
+		t.Fatal("QR not set")
+	}
+	if flags&0x000F != 0 {
+		t.Fatalf("rcode = %d, want 0 for A query", flags&0x000F)
+	}
+	if binary.BigEndian.Uint16(reply[4:6]) != 1 {
+		t.Fatalf("QDCOUNT = %d, want 1", binary.BigEndian.Uint16(reply[4:6]))
+	}
+	if an := binary.BigEndian.Uint16(reply[6:8]); an != 1 {
+		t.Fatalf("ANCOUNT = %d, want 1", an)
+	}
+	// answer: pointer to name + A record with relay IP
+	a := reply[len(reply)-4:]
+	if a[0] != 203 || a[3] != 9 {
+		t.Fatalf("answer = %v, want relay IP", a)
+	}
+	if rdlen := binary.BigEndian.Uint16(reply[len(reply)-6 : len(reply)-4]); rdlen != 4 {
+		t.Fatalf("rdlength = %d, want 4", rdlen)
+	}
+}
+
+func TestFakeDNSReplyNXDOMAIN(t *testing.T) {
+	q := buildDNSQuery("host.example", 28, 0xABCD, 0x0100) // AAAA query
+	relay := netip.MustParseAddr("203.0.113.9")
+	reply := fakeDNSReply(q, relay)
+	if reply == nil {
+		t.Fatal("nil reply")
+	}
+	if flags := binary.BigEndian.Uint16(reply[2:4]); flags&0x000F != 3 {
+		t.Fatalf("rcode = %d, want 3 (NXDOMAIN)", flags&0x000F)
+	}
+	if an := binary.BigEndian.Uint16(reply[6:8]); an != 0 {
+		t.Fatalf("ANCOUNT = %d, want 0", an)
+	}
+}
+
+func TestFakeDNSReplyMalformed(t *testing.T) {
+	relay := netip.MustParseAddr("203.0.113.9")
+	if fakeDNSReply([]byte("short"), relay) != nil {
+		t.Fatal("short query should be dropped")
+	}
+	// QDCOUNT = 0
+	q := make([]byte, 12)
+	if fakeDNSReply(q, relay) != nil {
+		t.Fatal("zero-question query should be dropped")
+	}
+	// truncated name
+	q = buildDNSQuery("example.com", 1, 0x1, 0x0100)
+	if fakeDNSReply(q[:len(q)-4], relay) != nil {
+		t.Fatal("truncated query should be dropped")
+	}
+}
+
+func TestMasqueradeFlowLifecycle(t *testing.T) {
+	// build directly to avoid opening a raw socket (needs privileges)
+	rec := &recordingFD{}
+	m := &masquerade{
+		mode:     masqHTTP,
+		fd:       rec.fd(),
+		relayP:   443,
+		flows:    make(map[masqKey]*fakeFlow),
+		httpResp: fakeHTTPResponse(),
+		done:     make(chan struct{}),
+	}
+	defer close(m.done)
+
+	probe := netip.MustParseAddr("198.51.100.7")
+	relay := netip.MustParseAddr("203.0.113.9")
+
+	// bare SYN
+	m.onTCPSYN(relay, 443, probe, 50000, 1000)
+	if len(rec.pkts) != 1 {
+		t.Fatalf("SYN should produce 1 packet, got %d", len(rec.pkts))
+	}
+	synack := rec.pkts[0]
+	if synack[33] != TCPFlagSyn|TCPFlagAck {
+		t.Fatalf("flags = %#x, want SYN|ACK", synack[33])
+	}
+	if ack := binary.BigEndian.Uint32(synack[28:32]); ack != 1001 {
+		t.Fatalf("ack = %d, want 1001", ack)
+	}
+	if binary.BigEndian.Uint16(synack[20:22]) != 443 {
+		t.Fatalf("src port = %d, want 443", binary.BigEndian.Uint16(synack[20:22]))
+	}
+
+	// data (HTTP GET) -> response chunk
+	rec.pkts = nil
+	m.onTCPData(relay, 443, probe, 50000, 1001, []byte("GET / HTTP/1.1\r\n\r\n"))
+	if len(rec.pkts) != 1 {
+		t.Fatalf("data should produce 1 packet, got %d", len(rec.pkts))
+	}
+	data := rec.pkts[0]
+	payload := data[52:] // 20 ip + 32 tcp (20 hdr + 12 options)
+	if !startsWith(string(payload), "HTTP/1.1 200 OK") {
+		t.Fatalf("unexpected payload: %q", payload[:min(len(payload), 40)])
+	}
+	if seq := binary.BigEndian.Uint32(data[24:28]); seq == 0 {
+		t.Fatal("seq should be relay ISN, got 0")
+	}
+
+	// unknown flow data -> no reply
+	rec.pkts = nil
+	m.onTCPData(relay, 443, netip.MustParseAddr("198.51.100.8"), 51000, 1, []byte("x"))
+	if len(rec.pkts) != 0 {
+		t.Fatalf("unknown flow should not get a reply")
+	}
+}
+
+func TestMasqueradeDNSFlow(t *testing.T) {
+	rec := &recordingFD{}
+	m := &masquerade{
+		mode:   masqDNS,
+		fd:     rec.fd(),
+		relayP: 53,
+		flows:  make(map[masqKey]*fakeFlow),
+		done:   make(chan struct{}),
+	}
+	defer close(m.done)
+
+	probe := netip.MustParseAddr("198.51.100.7")
+	relay := netip.MustParseAddr("203.0.113.9")
+	q := buildDNSQuery("example.com", 1, 0x4242, 0x0100)
+	m.onUDP(relay, 53, probe, 40000, q)
+	if len(rec.pkts) != 1 {
+		t.Fatalf("dns probe should get 1 reply, got %d", len(rec.pkts))
+	}
+	pkt := rec.pkts[0]
+	if pkt[9] != 17 {
+		t.Fatalf("protocol = %d, want UDP", pkt[9])
+	}
+	if binary.BigEndian.Uint16(pkt[22:24]) != 40000 {
+		t.Fatalf("dst port = %d, want 40000", binary.BigEndian.Uint16(pkt[22:24]))
+	}
+	udpPayload := pkt[28:]
+	// DNS reply parses
+	if len(udpPayload) < 12 || binary.BigEndian.Uint16(udpPayload[0:2]) != 0x4242 {
+		t.Fatalf("bad DNS reply in packet")
+	}
+
+	// non-DNS garbage -> no reply
+	rec.pkts = nil
+	m.onUDP(relay, 53, probe, 40000, []byte("garbage"))
+	if len(rec.pkts) != 0 {
+		t.Fatalf("garbage should not get a DNS reply")
+	}
+}
+
+func TestMasqueradeOff(t *testing.T) {
+	m, err := newMasquerade("", 443)
+	if err != nil || m != nil {
+		t.Fatalf("off mode should return nil, nil; got %v, %v", m, err)
+	}
+	m, err = newMasquerade("off", 443)
+	if err != nil || m != nil {
+		t.Fatalf("off mode should return nil, nil; got %v, %v", m, err)
+	}
+}
+
+// --- helpers ---
+
+type recordingFD struct {
+	pkts [][]byte
+}
+
+func (r *recordingFD) fd() *rawSendFD {
+	rf := &rawSendFD{}
+	rf.sendFn = func(pkt []byte, _ netip.Addr) error {
+		r.pkts = append(r.pkts, append([]byte(nil), pkt...))
+		return nil
+	}
+	return rf
+}
+
+func buildDNSQuery(name string, qtype uint16, id uint16, flags uint16) []byte {
+	q := make([]byte, 12)
+	binary.BigEndian.PutUint16(q[0:], id)
+	binary.BigEndian.PutUint16(q[2:], flags)
+	binary.BigEndian.PutUint16(q[4:], 1)
+	for _, part := range stringsSplit(name, ".") {
+		q = append(q, byte(len(part)))
+		q = append(q, part...)
+	}
+	q = append(q, 0)
+	q = binary.BigEndian.AppendUint16(q, qtype)
+	q = binary.BigEndian.AppendUint16(q, 1)
+	return q
+}
+
+func stringsSplit(s, sep string) []string {
+	var out []string
+	start := 0
+	for i := 0; i+len(sep) <= len(s); i++ {
+		if s[i:i+len(sep)] == sep {
+			out = append(out, s[start:i])
+			start = i + len(sep)
+		}
+	}
+	out = append(out, s[start:])
+	return out
+}
+
+func startsWith(s, prefix string) bool {
+	return len(s) >= len(prefix) && s[:len(prefix)] == prefix
+}
+
+func contains(s, sub string) bool {
+	for i := 0; i+len(sub) <= len(s); i++ {
+		if s[i:i+len(sub)] == sub {
+			return true
+		}
+	}
+	return false
+}
diff --git a/transport/internet/finalmask/rawpacket/platform.go b/transport/internet/finalmask/rawpacket/platform.go
new file mode 100644
index 000000000000..34a3a855dea4
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/platform.go
@@ -0,0 +1,5 @@
+//go:build darwin || freebsd || linux || (windows && (amd64 || 386))
+
+package rawpacket
+
+const PlatformSupported = true
diff --git a/transport/internet/finalmask/rawpacket/platform_unsupported.go b/transport/internet/finalmask/rawpacket/platform_unsupported.go
new file mode 100644
index 000000000000..5ef3145901aa
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/platform_unsupported.go
@@ -0,0 +1,5 @@
+//go:build !darwin && !freebsd && !linux && !(windows && (amd64 || 386))
+
+package rawpacket
+
+const PlatformSupported = false
diff --git a/transport/internet/finalmask/rawpacket/spoof_bpf_linux.go b/transport/internet/finalmask/rawpacket/spoof_bpf_linux.go
new file mode 100644
index 000000000000..4669618468ed
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_bpf_linux.go
@@ -0,0 +1,53 @@
+//go:build linux
+
+package rawpacket
+
+import (
+	"log"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+// sockFilter and sockFprog mirror the kernel's struct sock_filter /
+// struct sock_fprog (classic BPF). SO_ATTACH_FILTER is a Linux-only
+// socket option; other platforms build the stub below.
+type sockFilter struct {
+	Code uint16
+	Jt   uint8
+	Jf   uint8
+	K    uint32
+}
+
+type sockFprog struct {
+	Len    uint16
+	Filter *sockFilter
+}
+
+const (
+	bpfLdAbs       = 0x30 // BPF_LD|BPF_B|BPF_ABS: load byte at absolute offset
+	bpfJeq         = 0x15 // BPF_JMP|BPF_JEQ|BPF_K
+	bpfRet         = 0x06 // BPF_RET|BPF_K
+	bpfKeepAll     = 0xffffffff
+	bpfDrop        = 0
+	soAttachFilter = 26 // SOL_SOCKET level option (Linux)
+)
+
+// attachBPFFilter installs a filter that keeps only IPv4 packets whose
+// protocol byte (offset 9) matches proto, dropping everything else in
+// the kernel. Failures are logged but non-fatal: userspace already
+// filters by protocol.
+func attachBPFFilter(fd int, proto uint8) {
+	filter := []sockFilter{
+		{Code: bpfLdAbs, K: 9},                         // A = ip.proto
+		{Code: bpfJeq, Jt: 1, Jf: 0, K: uint32(proto)}, // if A == proto skip the drop
+		{Code: bpfRet, K: bpfDrop},                     // else drop
+		{Code: bpfRet, K: bpfKeepAll},                  // keep
+	}
+	fprog := sockFprog{Len: uint16(len(filter)), Filter: &filter[0]}
+	_, _, errno := unix.Syscall6(unix.SYS_SETSOCKOPT, uintptr(fd), uintptr(unix.SOL_SOCKET), uintptr(soAttachFilter),
+		uintptr(unsafe.Pointer(&fprog)), unsafe.Sizeof(fprog), 0)
+	if errno != 0 {
+		log.Printf("[rawpacket] failed to attach BPF filter (proto %d): %v", proto, errno)
+	}
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_bpf_stub.go b/transport/internet/finalmask/rawpacket/spoof_bpf_stub.go
new file mode 100644
index 000000000000..3bc6b70d762f
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_bpf_stub.go
@@ -0,0 +1,7 @@
+//go:build !linux
+
+package rawpacket
+
+// attachBPFFilter is a no-op on platforms without SO_ATTACH_FILTER
+// (darwin/freebsd raw sockets do not support classic-BPF attachment).
+func attachBPFFilter(fd int, proto uint8) {}
diff --git a/transport/internet/finalmask/rawpacket/spoof_conn.go b/transport/internet/finalmask/rawpacket/spoof_conn.go
new file mode 100644
index 000000000000..b0d72b9c91d8
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_conn.go
@@ -0,0 +1,240 @@
+package rawpacket
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"net/netip"
+	"os"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// dialCounter round-robins the spoof source IP across connections so each
+// session uses exactly one source address (per-session rotation instead of
+// per-packet). This keeps the relay's (sessionID -> client address)
+// mapping stable.
+var dialCounter atomic.Uint64
+
+type SpoofConn struct {
+	sid     [8]byte
+	crypto  *frameCrypto
+	sender  SpoofSender
+	tcp     *TCPSimState
+	demux   *frameDemux
+	recvCh  chan demuxData
+	relayIP netip.Addr
+	relayP  uint16
+
+	maxPayload int
+
+	writeMu sync.Mutex
+
+	keepaliveStop chan struct{}
+	closeOnce     sync.Once
+
+	readDeadline  atomic.Int64 // unixNano, 0 = none
+	writeDeadline atomic.Int64
+}
+
+func DialSpoof(relayAddr netip.AddrPort, spoofIPs []netip.Addr, srcPort uint16, ttl uint8, mtu uint32, sendProto, recvProto string, peerSpoofIP netip.Addr, psk []byte) (net.Conn, error) {
+	if len(psk) == 0 {
+		return nil, errors.New("rawpacket: auth (PSK) required in local mode")
+	}
+	if len(spoofIPs) == 0 {
+		return nil, errors.New("rawpacket: at least one spoof IP required")
+	}
+	if sendProto == "" {
+		sendProto = "tcp"
+	}
+	if recvProto == "" {
+		recvProto = "udp"
+	}
+
+	if recvProto == "icmp" || recvProto == "icmpv6" {
+		suppressICMPEchoReply()
+	}
+
+	sid, err := newSessionID()
+	if err != nil {
+		return nil, fmt.Errorf("rawpacket: session id: %w", err)
+	}
+	crypto, err := newFrameCrypto(psk, sid)
+	if err != nil {
+		return nil, fmt.Errorf("rawpacket: frame crypto: %w", err)
+	}
+
+	// One source IP per session: per-session rotation.
+	srcIP := spoofIPs[dialCounter.Add(1)%uint64(len(spoofIPs))]
+	sender, err := NewSender(sendProto, &SpoofSenderConfig{
+		SourceIPs:  []netip.Addr{srcIP},
+		SourcePort: srcPort,
+		TTL:        ttl,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("rawpacket: create sender: %w", err)
+	}
+
+	demux := getFrameDemux(recvProto, srcPort, peerSpoofIP)
+	recvCh := make(chan demuxData, 64)
+	if err := demux.register(sid, crypto, recvCh); err != nil {
+		sender.Close()
+		return nil, fmt.Errorf("rawpacket: create receiver: %w", err)
+	}
+
+	c := &SpoofConn{
+		sid:           sid,
+		crypto:        crypto,
+		sender:        sender,
+		tcp:           newTCPSimState(),
+		demux:         demux,
+		recvCh:        recvCh,
+		relayIP:       relayAddr.Addr(),
+		relayP:        relayAddr.Port(),
+		maxPayload:    maxPayloadForMTU(mtu),
+		keepaliveStop: make(chan struct{}),
+	}
+	go c.keepaliveLoop()
+	return c, nil
+}
+
+// maxPayloadForMTU bounds the frame payload so the largest possible wire
+// packet (IPv4 + TCP with options + frame overhead) stays within mtu.
+func maxPayloadForMTU(mtu uint32) int {
+	if mtu == 0 {
+		return frameMaxPayload
+	}
+	p := int(mtu) - 20 - 40 - frameOverhead
+	if p < 1 {
+		p = 1
+	}
+	if p > frameMaxPayload {
+		p = frameMaxPayload
+	}
+	return p
+}
+
+func (c *SpoofConn) Write(b []byte) (int, error) {
+	if len(b) == 0 {
+		return 0, nil
+	}
+	if dl := c.writeDeadline.Load(); dl != 0 {
+		if time.Now().UnixNano() >= dl {
+			return 0, os.ErrDeadlineExceeded
+		}
+	}
+	c.writeMu.Lock()
+	defer c.writeMu.Unlock()
+
+	written := 0
+	for len(b) > 0 {
+		chunk := b
+		if len(chunk) > c.maxPayload {
+			chunk = chunk[:c.maxPayload]
+		}
+		frame, err := c.crypto.seal(false, chunk, false)
+		if err != nil {
+			return written, err
+		}
+		if err := c.sender.Send(frame, c.relayIP, c.relayP, c.tcp); err != nil {
+			return written, err
+		}
+		written += len(chunk)
+		b = b[len(chunk):]
+	}
+	return written, nil
+}
+
+func (c *SpoofConn) Read(buf []byte) (int, error) {
+	dl := c.readDeadline.Load()
+	if dl != 0 && time.Now().UnixNano() >= dl {
+		return 0, os.ErrDeadlineExceeded
+	}
+
+	var timer *time.Timer
+	var timeout <-chan time.Time
+	if dl != 0 {
+		timer = time.NewTimer(time.Until(time.Unix(0, dl)))
+		timeout = timer.C
+		defer timer.Stop()
+	}
+
+	select {
+	case data, ok := <-c.recvCh:
+		if !ok {
+			return 0, errors.New("rawpacket: connection closed")
+		}
+		if data.tcp != nil && data.tcp.Flags != 0 {
+			c.tcp.observePeer(data.tcp.Seq, len(data.payload))
+		}
+		return copy(buf, data.payload), nil
+	case <-timeout:
+		return 0, os.ErrDeadlineExceeded
+	}
+}
+
+// keepaliveLoop keeps the relay session alive during idle periods so the
+// relay's garbage collector does not reap an idle but healthy connection.
+func (c *SpoofConn) keepaliveLoop() {
+	t := time.NewTicker(25 * time.Second)
+	defer t.Stop()
+	for {
+		select {
+		case <-c.keepaliveStop:
+			return
+		case <-t.C:
+			c.writeMu.Lock()
+			frame, err := c.crypto.seal(false, nil, true)
+			if err == nil {
+				_ = c.sender.Send(frame, c.relayIP, c.relayP, c.tcp)
+			}
+			c.writeMu.Unlock()
+		}
+	}
+}
+
+func (c *SpoofConn) Close() error {
+	c.closeOnce.Do(func() {
+		close(c.keepaliveStop)
+		c.demux.unregister(c.sid)
+		c.sender.Close()
+	})
+	return nil
+}
+
+func (c *SpoofConn) LocalAddr() net.Addr {
+	return &net.TCPAddr{IP: net.IPv4(0, 0, 0, 0), Port: 0}
+}
+
+func (c *SpoofConn) RemoteAddr() net.Addr {
+	return &net.TCPAddr{IP: c.relayIP.AsSlice(), Port: int(c.relayP)}
+}
+
+func setDeadline(d *atomic.Int64, t time.Time) error {
+	if t.IsZero() {
+		d.Store(0)
+		return nil
+	}
+	d.Store(t.UnixNano())
+	return nil
+}
+
+func (c *SpoofConn) SetDeadline(t time.Time) error {
+	if err := setDeadline(&c.readDeadline, t); err != nil {
+		return err
+	}
+	return setDeadline(&c.writeDeadline, t)
+}
+
+func (c *SpoofConn) SetReadDeadline(t time.Time) error {
+	return setDeadline(&c.readDeadline, t)
+}
+
+func (c *SpoofConn) SetWriteDeadline(t time.Time) error {
+	return setDeadline(&c.writeDeadline, t)
+}
+
+func (c *SpoofConn) TcpMaskConn()      {}
+func (c *SpoofConn) RawConn() net.Conn { return nil }
+func (c *SpoofConn) Splice() bool      { return false }
diff --git a/transport/internet/finalmask/rawpacket/spoof_icmp_utils.go b/transport/internet/finalmask/rawpacket/spoof_icmp_utils.go
new file mode 100644
index 000000000000..3b14f7681dbb
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_icmp_utils.go
@@ -0,0 +1,48 @@
+package rawpacket
+
+import (
+	"log"
+	"os/exec"
+	"runtime"
+)
+
+func suppressICMPEchoReply() bool {
+	switch runtime.GOOS {
+	case "linux":
+		err := exec.Command("sysctl", "-w", "net.ipv4.icmp_echo_ignore_all=1").Run()
+		if err != nil {
+			log.Printf("[rawpacket] failed to suppress ICMP echo replies: %v", err)
+			return false
+		}
+		log.Printf("[rawpacket] suppressed kernel ICMP echo replies")
+		return true
+	case "freebsd", "openbsd":
+		err := exec.Command("sysctl", "net.inet.icmp.bmcastecho=0").Run()
+		if err != nil {
+			log.Printf("[rawpacket] failed to suppress ICMP echo replies on %s: %v", runtime.GOOS, err)
+			return false
+		}
+		log.Printf("[rawpacket] suppressed kernel ICMP echo replies on %s", runtime.GOOS)
+		return true
+	default:
+		log.Printf("[rawpacket] ICMP echo reply suppression not supported on %s", runtime.GOOS)
+		return false
+	}
+}
+
+func restoreICMPEchoReply() {
+	switch runtime.GOOS {
+	case "linux":
+		err := exec.Command("sysctl", "-w", "net.ipv4.icmp_echo_ignore_all=0").Run()
+		if err != nil {
+			log.Printf("[rawpacket] failed to restore ICMP echo replies: %v", err)
+			return
+		}
+		log.Printf("[rawpacket] restored kernel ICMP echo replies")
+	case "freebsd", "openbsd":
+		err := exec.Command("sysctl", "net.inet.icmp.bmcastecho=1").Run()
+		if err != nil {
+			log.Printf("[rawpacket] failed to restore ICMP echo replies on %s: %v", runtime.GOOS, err)
+		}
+	}
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_ip.go b/transport/internet/finalmask/rawpacket/spoof_ip.go
new file mode 100644
index 000000000000..505601372142
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_ip.go
@@ -0,0 +1,75 @@
+package rawpacket
+
+import (
+	"encoding/binary"
+	"net/netip"
+)
+
+// BuildIPv4Header builds a 20-byte IPv4 header. df sets the Don't
+// Fragment bit (real hosts set it; prevents MTU-blackhole fragmentation).
+func BuildIPv4Header(totalLen uint16, id uint16, ttl uint8, protocol uint8, src, dst netip.Addr, df bool) []byte {
+	b := make([]byte, 20)
+	b[0] = (4 << 4) | 5
+	b[1] = 0
+	binary.BigEndian.PutUint16(b[2:], totalLen)
+	binary.BigEndian.PutUint16(b[4:], id)
+	if df {
+		binary.BigEndian.PutUint16(b[6:], 0x4000)
+	} else {
+		binary.BigEndian.PutUint16(b[6:], 0)
+	}
+	b[8] = ttl
+	b[9] = protocol
+	copy(b[12:16], src.AsSlice())
+	copy(b[16:20], dst.AsSlice())
+	csum := Checksum(b[:20], 0)
+	binary.BigEndian.PutUint16(b[10:], ^csum)
+	return b
+}
+
+func BuildIPv6Header(payloadLen uint16, transportProtocol uint8, hopLimit uint8, src, dst netip.Addr) []byte {
+	b := make([]byte, 40)
+	binary.BigEndian.PutUint32(b[0:], 6<<28)
+	binary.BigEndian.PutUint16(b[4:], payloadLen)
+	b[6] = transportProtocol
+	b[7] = hopLimit
+	copy(b[8:24], src.AsSlice())
+	copy(b[24:40], dst.AsSlice())
+	return b
+}
+
+func IPv4PseudoHeaderChecksum(src, dst netip.Addr, protocol uint8, tcpLen uint16) uint16 {
+	var csum uint32
+	srcB := src.As4()
+	dstB := dst.As4()
+	for i := 0; i < 4; i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(srcB[i:]))
+	}
+	for i := 0; i < 4; i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(dstB[i:]))
+	}
+	csum += uint32(protocol)
+	csum += uint32(tcpLen)
+	for csum > 0xffff {
+		csum = (csum >> 16) + (csum & 0xffff)
+	}
+	return uint16(csum)
+}
+
+func IPv6PseudoHeaderChecksum(src, dst netip.Addr, protocol uint8, totalLen uint32) uint16 {
+	var csum uint32
+	srcB := src.As16()
+	dstB := dst.As16()
+	for i := 0; i < 16; i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(srcB[i:]))
+	}
+	for i := 0; i < 16; i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(dstB[i:]))
+	}
+	csum += uint32(protocol)
+	csum += totalLen
+	for csum > 0xffff {
+		csum = (csum >> 16) + (csum & 0xffff)
+	}
+	return uint16(csum)
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_rawsend.go b/transport/internet/finalmask/rawpacket/spoof_rawsend.go
new file mode 100644
index 000000000000..1c10faef91b0
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_rawsend.go
@@ -0,0 +1,93 @@
+//go:build darwin || freebsd || linux
+
+package rawpacket
+
+import (
+	"fmt"
+	"net/netip"
+	"sync"
+
+	"golang.org/x/sys/unix"
+)
+
+type rawSendFD struct {
+	fd       int
+	sockAddr unix.Sockaddr
+	// sendFn, when set, replaces the real send path (used by tests).
+	sendFn func(pkt []byte, dstIP netip.Addr) error
+	mu     sync.Mutex
+	closed bool
+}
+
+func openRawSender(dstIP netip.Addr) (*rawSendFD, error) {
+	if !dstIP.Is4() {
+		return nil, fmt.Errorf("rawpacket: IPv6 raw sender not yet supported")
+	}
+
+	fd, err := openRawSenderAny()
+	if err != nil {
+		return nil, err
+	}
+	sa := &unix.SockaddrInet4{}
+	sa.Addr = dstIP.As4()
+	fd.sockAddr = sa
+	return fd, nil
+}
+
+// openRawSenderAny opens a raw sending socket without binding it to a
+// fixed destination. Used by the masquerade responder, which must send
+// to arbitrary probe addresses.
+func openRawSenderAny() (*rawSendFD, error) {
+	fd, err := unix.Socket(unix.AF_INET, unix.SOCK_RAW, unix.IPPROTO_RAW)
+	if err != nil {
+		return nil, fmt.Errorf("rawpacket: open SOCK_RAW: %w", err)
+	}
+	err = unix.SetsockoptInt(fd, unix.IPPROTO_IP, unix.IP_HDRINCL, 1)
+	if err != nil {
+		unix.Close(fd)
+		return nil, fmt.Errorf("rawpacket: set IP_HDRINCL: %w", err)
+	}
+
+	_ = unix.SetsockoptInt(fd, unix.SOL_SOCKET, unix.SO_SNDBUF, 4*1024*1024)
+	return &rawSendFD{fd: fd}, nil
+}
+
+func (r *rawSendFD) send(packet []byte) error {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.closed {
+		return fmt.Errorf("rawpacket: raw sender closed")
+	}
+	if r.sockAddr == nil {
+		return fmt.Errorf("rawpacket: raw sender has no destination")
+	}
+	return unix.Sendto(r.fd, packet, 0, r.sockAddr)
+}
+
+// sendTo sends packet to dstIP, building the socket address per call.
+func (r *rawSendFD) sendTo(packet []byte, dstIP netip.Addr) error {
+	if r.sendFn != nil {
+		return r.sendFn(packet, dstIP)
+	}
+	if !dstIP.Is4() {
+		return fmt.Errorf("rawpacket: IPv6 raw sender not yet supported")
+	}
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.closed {
+		return fmt.Errorf("rawpacket: raw sender closed")
+	}
+	sa := &unix.SockaddrInet4{}
+	sa.Addr = dstIP.As4()
+	return unix.Sendto(r.fd, packet, 0, sa)
+}
+
+func (r *rawSendFD) close() error {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.closed {
+		return nil
+	}
+	r.closed = true
+	return unix.Close(r.fd)
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_rawsend_stub.go b/transport/internet/finalmask/rawpacket/spoof_rawsend_stub.go
new file mode 100644
index 000000000000..1d59e4cfc6e6
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_rawsend_stub.go
@@ -0,0 +1,30 @@
+//go:build !darwin && !freebsd && !linux && !(windows && (amd64 || 386))
+
+package rawpacket
+
+import (
+	"fmt"
+	"net/netip"
+)
+
+type rawSendFD struct{}
+
+func openRawSender(dstIP netip.Addr) (*rawSendFD, error) {
+	return nil, fmt.Errorf("rawpacket: raw sockets not supported on this platform")
+}
+
+func openRawSenderAny() (*rawSendFD, error) {
+	return nil, fmt.Errorf("rawpacket: raw sockets not supported on this platform")
+}
+
+func (r *rawSendFD) send(packet []byte) error {
+	return fmt.Errorf("rawpacket: raw sockets not supported on this platform")
+}
+
+func (r *rawSendFD) sendTo(packet []byte, dstIP netip.Addr) error {
+	return fmt.Errorf("rawpacket: raw sockets not supported on this platform")
+}
+
+func (r *rawSendFD) close() error {
+	return nil
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_rawsend_windows.go b/transport/internet/finalmask/rawpacket/spoof_rawsend_windows.go
new file mode 100644
index 000000000000..c5a29e7e0db1
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_rawsend_windows.go
@@ -0,0 +1,68 @@
+//go:build windows && (amd64 || 386)
+
+package rawpacket
+
+import (
+	"fmt"
+	"net/netip"
+	"sync"
+
+	"github.com/xtls/xray-core/transport/internet/finalmask/rawpacket/windivert"
+)
+
+type rawSendFD struct {
+	h *windivert.Handle
+	// sendFn, when set, replaces the real send path (used by tests).
+	sendFn func(pkt []byte, dstIP netip.Addr) error
+	mu     sync.Mutex
+	closed bool
+}
+
+func openRawSender(dstIP netip.Addr) (*rawSendFD, error) {
+	return openRawSenderAny()
+}
+
+// openRawSenderAny opens a WinDivert send handle. WinDivert injects
+// packets from the header contents, so no destination binding is needed.
+func openRawSenderAny() (*rawSendFD, error) {
+	h, err := windivert.Open(windivert.AcceptAll(), windivert.LayerNetwork, windivert.PriorityLowest, windivert.FlagSendOnly)
+	if err != nil {
+		return nil, fmt.Errorf("rawpacket: WinDivert open: %w", err)
+	}
+	return &rawSendFD{h: h}, nil
+}
+
+func (r *rawSendFD) send(packet []byte) error {
+	return r.sendTo(packet, netip.Addr{})
+}
+
+// sendTo sends packet via WinDivert; the destination is read from the
+// packet itself.
+func (r *rawSendFD) sendTo(packet []byte, dstIP netip.Addr) error {
+	if r.sendFn != nil {
+		return r.sendFn(packet, dstIP)
+	}
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.closed {
+		return fmt.Errorf("rawpacket: WinDivert sender closed")
+	}
+	var addr windivert.Address
+	addr.SetIPChecksum(true)
+	addr.SetTCPChecksum(true)
+	_, err := r.h.Send(packet, &addr)
+	if err != nil {
+		return fmt.Errorf("rawpacket: WinDivert send: %w", err)
+	}
+	return nil
+}
+
+func (r *rawSendFD) close() error {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.closed {
+		return nil
+	}
+	r.closed = true
+	return r.h.Close()
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_receiver.go b/transport/internet/finalmask/rawpacket/spoof_receiver.go
new file mode 100644
index 000000000000..af3814b03092
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_receiver.go
@@ -0,0 +1,178 @@
+package rawpacket
+
+import (
+	"errors"
+	"net/netip"
+)
+
+var errReceiverClosed = errors.New("rawpacket: receiver closed")
+
+// rawPktRecv is the platform-specific raw socket: unix SOCK_RAW on
+// darwin/freebsd/linux, WinDivert on windows (amd64/386).
+type rawPktRecv interface {
+	// recv returns a copy of one raw IP packet. ok is false when the
+	// socket is closed or a transient read failure occurred (callers
+	// must tolerate spurious false returns and re-try).
+	recv() (pkt []byte, ok bool)
+	// closed reports whether the socket has been closed (recv will no
+	// longer produce packets and errReceiverClosed is the permanent
+	// outcome).
+	closed() bool
+	close()
+}
+
+type tcpReceiver struct {
+	raw rawPktRecv
+	cfg *SpoofReceiverConfig
+}
+
+func newTCPReceiver(cfg *SpoofReceiverConfig) (*tcpReceiver, error) {
+	raw, err := newRawRecvSocket(ProtocolTCP, cfg.BufferSize)
+	if err != nil {
+		return nil, err
+	}
+	return &tcpReceiver{raw: raw, cfg: cfg}, nil
+}
+
+func (r *tcpReceiver) Receive() ([]byte, netip.Addr, uint16, *TCPMeta, error) {
+	for {
+		pkt, ok := r.raw.recv()
+		if !ok {
+			if r.raw.closed() {
+				return nil, netip.Addr{}, 0, nil, errReceiverClosed
+			}
+			continue
+		}
+		seq, flags, payload, srcIP, dstIP, srcPort, dstPort, ok := ParseRawTCPPacket(pkt)
+		if !ok || dstPort != r.cfg.ListenPort {
+			continue
+		}
+		if r.cfg.PeerSpoofIP.IsValid() && srcIP != r.cfg.PeerSpoofIP {
+			continue
+		}
+		return payload, srcIP, srcPort, &TCPMeta{Seq: seq, Flags: flags, DstIP: dstIP, DstPort: dstPort}, nil
+	}
+}
+
+func (r *tcpReceiver) Close() error {
+	r.raw.close()
+	return nil
+}
+
+type udpReceiver struct {
+	raw rawPktRecv
+	cfg *SpoofReceiverConfig
+}
+
+func newUDPReceiver(cfg *SpoofReceiverConfig) (*udpReceiver, error) {
+	raw, err := newRawRecvSocket(ProtocolUDP, cfg.BufferSize)
+	if err != nil {
+		return nil, err
+	}
+	return &udpReceiver{raw: raw, cfg: cfg}, nil
+}
+
+func (r *udpReceiver) Receive() ([]byte, netip.Addr, uint16, *TCPMeta, error) {
+	for {
+		pkt, ok := r.raw.recv()
+		if !ok {
+			if r.raw.closed() {
+				return nil, netip.Addr{}, 0, nil, errReceiverClosed
+			}
+			continue
+		}
+		payload, srcPort, dstPort, ok := ParseUDPPacket(pkt)
+		if !ok || dstPort != r.cfg.ListenPort {
+			continue
+		}
+		srcIP, dstIP, _ := ParseSrcIP(pkt, false)
+		if r.cfg.PeerSpoofIP.IsValid() && srcIP != r.cfg.PeerSpoofIP {
+			continue
+		}
+		return payload, srcIP, srcPort, &TCPMeta{DstIP: dstIP, DstPort: dstPort}, nil
+	}
+}
+
+func (r *udpReceiver) Close() error {
+	r.raw.close()
+	return nil
+}
+
+type icmpReceiver struct {
+	raw rawPktRecv
+	cfg *SpoofReceiverConfig
+}
+
+func newICMPReceiver(cfg *SpoofReceiverConfig) (*icmpReceiver, error) {
+	raw, err := newRawRecvSocket(ProtocolICMP, cfg.BufferSize)
+	if err != nil {
+		return nil, err
+	}
+	return &icmpReceiver{raw: raw, cfg: cfg}, nil
+}
+
+func (r *icmpReceiver) Receive() ([]byte, netip.Addr, uint16, *TCPMeta, error) {
+	for {
+		pkt, ok := r.raw.recv()
+		if !ok {
+			if r.raw.closed() {
+				return nil, netip.Addr{}, 0, nil, errReceiverClosed
+			}
+			continue
+		}
+		id, _, payload, ok := ParseICMPv4Echo(pkt)
+		if !ok {
+			continue
+		}
+		srcIP, _, _ := ParseSrcIP(pkt, false)
+		if r.cfg.PeerSpoofIP.IsValid() && srcIP != r.cfg.PeerSpoofIP {
+			continue
+		}
+		return payload, srcIP, id, nil, nil
+	}
+}
+
+func (r *icmpReceiver) Close() error {
+	r.raw.close()
+	return nil
+}
+
+type icmpv6Receiver struct {
+	raw rawPktRecv
+	cfg *SpoofReceiverConfig
+}
+
+func newICMPv6Receiver(cfg *SpoofReceiverConfig) (*icmpv6Receiver, error) {
+	// Non-standard: protocol 58 on IPv4 (same as reference)
+	raw, err := newRawRecvSocket(ProtocolICMPv6, cfg.BufferSize)
+	if err != nil {
+		return nil, err
+	}
+	return &icmpv6Receiver{raw: raw, cfg: cfg}, nil
+}
+
+func (r *icmpv6Receiver) Receive() ([]byte, netip.Addr, uint16, *TCPMeta, error) {
+	for {
+		pkt, ok := r.raw.recv()
+		if !ok {
+			if r.raw.closed() {
+				return nil, netip.Addr{}, 0, nil, errReceiverClosed
+			}
+			continue
+		}
+		id, _, payload, ok := ParseICMPv6Echo(pkt)
+		if !ok {
+			continue
+		}
+		srcIP, _, _ := ParseSrcIP(pkt, false)
+		if r.cfg.PeerSpoofIP.IsValid() && srcIP != r.cfg.PeerSpoofIP {
+			continue
+		}
+		return payload, srcIP, id, nil, nil
+	}
+}
+
+func (r *icmpv6Receiver) Close() error {
+	r.raw.close()
+	return nil
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_recv_stub.go b/transport/internet/finalmask/rawpacket/spoof_recv_stub.go
new file mode 100644
index 000000000000..419237d0fab2
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_recv_stub.go
@@ -0,0 +1,21 @@
+//go:build !darwin && !freebsd && !linux && !(windows && (amd64 || 386))
+
+package rawpacket
+
+import "fmt"
+
+type rawRecvSocket struct{}
+
+func newRawRecvSocket(proto uint8, bufSize int) (*rawRecvSocket, error) {
+	return nil, fmt.Errorf("rawpacket: raw sockets not supported on this platform")
+}
+
+func (r *rawRecvSocket) recv() ([]byte, bool) {
+	return nil, false
+}
+
+func (r *rawRecvSocket) closed() bool {
+	return true
+}
+
+func (r *rawRecvSocket) close() {}
diff --git a/transport/internet/finalmask/rawpacket/spoof_recv_unix.go b/transport/internet/finalmask/rawpacket/spoof_recv_unix.go
new file mode 100644
index 000000000000..1dda4aead7f3
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_recv_unix.go
@@ -0,0 +1,63 @@
+//go:build darwin || freebsd || linux
+
+package rawpacket
+
+import (
+	"fmt"
+	"runtime"
+
+	"golang.org/x/sys/unix"
+)
+
+type rawRecvSocket struct {
+	fd         int
+	buf        []byte
+	closedFlag bool
+	proto      uint8
+}
+
+func newRawRecvSocket(proto uint8, bufSize int) (*rawRecvSocket, error) {
+	fd, err := unix.Socket(unix.AF_INET, unix.SOCK_RAW, int(proto))
+	if err != nil {
+		return nil, fmt.Errorf("rawpacket: socket: %w", err)
+	}
+	if bufSize > 0 {
+		_ = unix.SetsockoptInt(fd, unix.SOL_SOCKET, unix.SO_RCVBUF, bufSize)
+	}
+	// 1-second timeout for clean shutdown
+	tv := unix.Timeval{Sec: 1, Usec: 0}
+	_ = unix.SetsockoptTimeval(fd, unix.SOL_SOCKET, unix.SO_RCVTIMEO, &tv)
+	// Linux only: attach a classic-BPF filter so the kernel drops
+	// non-matching protocol traffic before userspace sees it.
+	if runtime.GOOS == "linux" {
+		attachBPFFilter(fd, proto)
+	}
+	return &rawRecvSocket{fd: fd, buf: make([]byte, 65536), proto: proto}, nil
+}
+
+func (r *rawRecvSocket) recv() ([]byte, bool) {
+	if r.closedFlag {
+		return nil, false
+	}
+	n, _, err := unix.Recvfrom(r.fd, r.buf, 0)
+	if err != nil {
+		return nil, false
+	}
+	if n == 0 {
+		return nil, false
+	}
+	out := make([]byte, n)
+	copy(out, r.buf[:n])
+	return out, true
+}
+
+func (r *rawRecvSocket) closed() bool {
+	return r.closedFlag
+}
+
+func (r *rawRecvSocket) close() {
+	if !r.closedFlag {
+		r.closedFlag = true
+		unix.Close(r.fd)
+	}
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_recv_windows.go b/transport/internet/finalmask/rawpacket/spoof_recv_windows.go
new file mode 100644
index 000000000000..a5fec04068ae
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_recv_windows.go
@@ -0,0 +1,59 @@
+//go:build windows && (amd64 || 386)
+
+package rawpacket
+
+import (
+	"fmt"
+	"sync"
+
+	"github.com/xtls/xray-core/transport/internet/finalmask/rawpacket/windivert"
+)
+
+type rawRecvSocket struct {
+	h          *windivert.Handle
+	buf        []byte
+	mu         sync.Mutex
+	closedFlag bool
+	proto      uint8
+}
+
+func newRawRecvSocket(proto uint8, bufSize int) (*rawRecvSocket, error) {
+	h, err := windivert.Open(windivert.AcceptAll(), windivert.LayerNetwork, windivert.PriorityLowest, windivert.FlagSniff)
+	if err != nil {
+		return nil, fmt.Errorf("rawpacket: WinDivert open: %w", err)
+	}
+	return &rawRecvSocket{h: h, buf: make([]byte, windivert.MTUMax), proto: proto}, nil
+}
+
+func (r *rawRecvSocket) recv() ([]byte, bool) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.closedFlag {
+		return nil, false
+	}
+	n, _, err := r.h.Recv(r.buf)
+	if err != nil {
+		return nil, false
+	}
+	if n == 0 {
+		return nil, false
+	}
+	out := make([]byte, n)
+	copy(out, r.buf[:n])
+	return out, true
+}
+
+func (r *rawRecvSocket) closed() bool {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	return r.closedFlag
+}
+
+func (r *rawRecvSocket) close() {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if !r.closedFlag {
+		r.closedFlag = true
+		_ = r.h.Close()
+	}
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_relay.go b/transport/internet/finalmask/rawpacket/spoof_relay.go
new file mode 100644
index 000000000000..760cfe67bd3c
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_relay.go
@@ -0,0 +1,353 @@
+package rawpacket
+
+import (
+	"errors"
+	"net"
+	"net/netip"
+	"sync"
+	"time"
+)
+
+type Relay struct {
+	cfg            *RelayConfig
+	psk            []byte
+	recver         SpoofReceiver
+	sender         SpoofSender
+	done           chan struct{}
+	closeOnce      sync.Once
+	icmpSuppressed bool
+	maxPayload     int
+	sessionTimeout time.Duration
+	rstManaged     bool
+	masq           *masquerade
+
+	man *SessionManager
+
+	recentSIDs map[[8]byte]time.Time
+	recentMu   sync.Mutex
+}
+
+const (
+	relaySessionTimeout = 120 * time.Second
+	relaySIDRemember    = 10 * time.Minute
+)
+
+func NewRelay(cfg *RelayConfig) (*Relay, error) {
+	if cfg.SendTransport == "" {
+		cfg.SendTransport = "udp"
+	}
+	if cfg.RecvTransport == "" {
+		cfg.RecvTransport = "tcp"
+	}
+	if len(cfg.Auth) == 0 {
+		return nil, errors.New("rawpacket: auth (PSK) required in remote mode")
+	}
+
+	if cfg.RecvTransport == "icmp" || cfg.RecvTransport == "icmpv6" {
+		if suppressICMPEchoReply() {
+			cfg.icmpSuppressed = true
+		}
+	}
+
+	var spoofIPs []netip.Addr
+	if len(cfg.SpoofIPs) > 0 {
+		spoofIPs, _ = ParseIPs(cfg.SpoofIPs)
+	}
+	if len(spoofIPs) == 0 && cfg.SpoofIP.IsValid() {
+		spoofIPs = []netip.Addr{cfg.SpoofIP}
+	}
+	if len(spoofIPs) == 0 {
+		spoofIPs = []netip.Addr{netip.MustParseAddr("127.0.0.1")}
+	}
+
+	recver, err := NewReceiver(cfg.RecvTransport, &SpoofReceiverConfig{
+		ListenPort:  cfg.ListenPort,
+		PeerSpoofIP: cfg.PeerSpoofIP,
+		BufferSize:  4 * 1024 * 1024,
+	})
+	if err != nil {
+		if cfg.icmpSuppressed {
+			restoreICMPEchoReply()
+		}
+		return nil, err
+	}
+
+	sender, err := NewSender(cfg.SendTransport, &SpoofSenderConfig{
+		SourceIPs:  spoofIPs,
+		SourcePort: cfg.SpoofPort,
+		TTL:        64,
+		Server:     true,
+	})
+	if err != nil {
+		recver.Close()
+		if cfg.icmpSuppressed {
+			restoreICMPEchoReply()
+		}
+		return nil, err
+	}
+
+	r := &Relay{
+		cfg:            cfg,
+		psk:            []byte(cfg.Auth),
+		recver:         recver,
+		sender:         sender,
+		done:           make(chan struct{}),
+		icmpSuppressed: cfg.icmpSuppressed,
+		maxPayload:     maxPayloadForMTU(cfg.Mtu),
+		sessionTimeout: relaySessionTimeout,
+		man:            NewSessionManager(),
+		recentSIDs:     make(map[[8]byte]time.Time),
+	}
+	if cfg.SuppressRst {
+		r.rstManaged = suppressKernelRST(cfg.ListenPort)
+	}
+	masq, masqErr := newMasquerade(cfg.Masquerade, cfg.ListenPort)
+	if masqErr != nil {
+		r.Close()
+		return nil, masqErr
+	}
+	r.masq = masq
+	return r, nil
+}
+
+func (r *Relay) Run() {
+	go r.uplinkLoop()
+	go r.janitorLoop()
+	<-r.done
+}
+
+func (r *Relay) dialTarget() (net.Conn, error) {
+	return net.DialTimeout(r.cfg.ForwardTransport, r.cfg.ForwardAddr, 10*time.Second)
+}
+
+func (r *Relay) uplinkLoop() {
+	for {
+		select {
+		case <-r.done:
+			return
+		default:
+		}
+
+		pkt, srcIP, srcPort, tcp, err := r.recver.Receive()
+		if err != nil {
+			return
+		}
+		if len(pkt) == 0 {
+			// A TCP segment without payload is never a tunnel frame:
+			// bare SYNs are handshake probes from scanners.
+			if r.masq != nil && tcp != nil && tcp.Flags&TCPFlagSyn != 0 && tcp.Flags&TCPFlagAck == 0 {
+				r.masq.onTCPSYN(tcp.DstIP, tcp.DstPort, srcIP, srcPort, tcp.Seq)
+			}
+			continue
+		}
+		r.handleFrame(pkt, srcIP, srcPort, tcp)
+	}
+}
+
+func (r *Relay) handleFrame(pkt []byte, srcIP netip.Addr, srcPort uint16, tcp *TCPMeta) {
+	sid, ok := frameSessionID(pkt)
+	if !ok {
+		r.masqueradeProbe(pkt, srcIP, srcPort, tcp)
+		return
+	}
+	s := r.man.Get(sid)
+	if s == nil {
+		if !r.handleNewSession(sid, pkt, srcIP, srcPort) {
+			r.masqueradeProbe(pkt, srcIP, srcPort, tcp)
+		}
+		return
+	}
+	if !r.deliverToSession(s, pkt, tcp) {
+		r.masqueradeProbe(pkt, srcIP, srcPort, tcp)
+	}
+}
+
+// masqueradeProbe answers packets that do not belong to any tunnel
+// session (failed frame parse or decryption) with fake service traffic.
+func (r *Relay) masqueradeProbe(pkt []byte, srcIP netip.Addr, srcPort uint16, tcp *TCPMeta) {
+	if r.masq == nil || tcp == nil {
+		return
+	}
+	if tcp.Flags != 0 {
+		r.masq.onTCPData(tcp.DstIP, tcp.DstPort, srcIP, srcPort, tcp.Seq, pkt)
+	} else {
+		r.masq.onUDP(tcp.DstIP, tcp.DstPort, srcIP, srcPort, pkt)
+	}
+}
+
+func (r *Relay) handleNewSession(sid [8]byte, pkt []byte, srcIP netip.Addr, srcPort uint16) bool {
+	if r.recentSIDSeen(sid) {
+		// Replay of a session that was already torn down: drop.
+		return false
+	}
+	crypto, err := newFrameCrypto(r.psk, sid)
+	if err != nil {
+		return false
+	}
+	payload, flags, err := crypto.open(pkt, false)
+	if err != nil {
+		return false
+	}
+	if flags&frameFlagKeepalive != 0 {
+		// A keepalive for a session that no longer exists: ignore.
+		return false
+	}
+	targetConn, err := r.dialTarget()
+	if err != nil {
+		return false
+	}
+	s := r.man.Add(sid, srcIP, srcPort, targetConn, crypto, newTCPSimState())
+	r.rememberSID(sid)
+	go r.forwardSession(s)
+	if len(payload) > 0 {
+		writeTarget(s, payload)
+	}
+	return true
+}
+
+func (r *Relay) deliverToSession(s *RelaySession, pkt []byte, tcp *TCPMeta) bool {
+	s.mu.Lock()
+	if s.closed {
+		s.mu.Unlock()
+		return false
+	}
+	s.mu.Unlock()
+
+	payload, _, err := s.crypto.open(pkt, false)
+	if err != nil {
+		return false
+	}
+	if tcp != nil && tcp.Flags != 0 {
+		s.tcp.observeClientSeq(tcp.Seq, len(pkt))
+	}
+	s.mu.Lock()
+	s.LastSeen = time.Now()
+	s.mu.Unlock()
+
+	if len(payload) > 0 {
+		if !writeTarget(s, payload) {
+			r.man.Remove(s.ID)
+			return false
+		}
+	}
+	return true
+}
+
+// writeTarget writes the whole payload to the target connection, handling
+// partial writes. Returns false if the write failed (caller should remove
+// the session).
+func writeTarget(s *RelaySession, data []byte) bool {
+	if s.TargetConn == nil {
+		return false
+	}
+	_ = s.TargetConn.SetWriteDeadline(time.Now().Add(30 * time.Second))
+	n := 0
+	for n < len(data) {
+		m, err := s.TargetConn.Write(data[n:])
+		if err != nil {
+			return false
+		}
+		if m == 0 {
+			return false
+		}
+		n += m
+	}
+	return true
+}
+
+// forwardSession pumps target->client data for one session. It exits on
+// read error or EOF and removes the session.
+func (r *Relay) forwardSession(s *RelaySession) {
+	buf := make([]byte, 64*1024)
+	for {
+		n, err := s.TargetConn.Read(buf)
+		if err != nil {
+			r.man.Remove(s.ID)
+			return
+		}
+		if n == 0 {
+			continue
+		}
+		frames, ferr := s.crypto.sealSplit(true, buf[:n], r.maxPayload, false)
+		if ferr != nil {
+			continue
+		}
+		ok := true
+		for _, f := range frames {
+			if serr := r.sender.Send(f, s.ClientIP, s.ClientPort, s.tcp); serr != nil {
+				ok = false
+				break
+			}
+		}
+		if ok {
+			s.mu.Lock()
+			s.LastSeen = time.Now()
+			s.mu.Unlock()
+		} else {
+			r.man.Remove(s.ID)
+			return
+		}
+	}
+}
+
+// janitorLoop reaps sessions idle for longer than sessionTimeout and
+// prunes the recent-session-ID anti-replay set.
+func (r *Relay) janitorLoop() {
+	t := time.NewTicker(15 * time.Second)
+	defer t.Stop()
+	for {
+		select {
+		case <-r.done:
+			return
+		case <-t.C:
+			now := time.Now()
+			for _, s := range r.man.All() {
+				s.mu.Lock()
+				idle := now.Sub(s.LastSeen)
+				s.mu.Unlock()
+				if idle > r.sessionTimeout {
+					r.man.Remove(s.ID)
+				}
+			}
+			r.pruneRecentSIDs(now)
+		}
+	}
+}
+
+func (r *Relay) rememberSID(sid [8]byte) {
+	r.recentMu.Lock()
+	r.recentSIDs[sid] = time.Now()
+	r.recentMu.Unlock()
+}
+
+func (r *Relay) recentSIDSeen(sid [8]byte) bool {
+	r.recentMu.Lock()
+	defer r.recentMu.Unlock()
+	_, ok := r.recentSIDs[sid]
+	return ok
+}
+
+func (r *Relay) pruneRecentSIDs(now time.Time) {
+	r.recentMu.Lock()
+	defer r.recentMu.Unlock()
+	for sid, t := range r.recentSIDs {
+		if now.Sub(t) > relaySIDRemember {
+			delete(r.recentSIDs, sid)
+		}
+	}
+}
+
+func (r *Relay) Close() {
+	r.closeOnce.Do(func() {
+		close(r.done)
+		r.recver.Close()
+		r.sender.Close()
+		r.man.Close()
+		if r.icmpSuppressed {
+			restoreICMPEchoReply()
+		}
+		if r.rstManaged {
+			restoreKernelRST(r.cfg.ListenPort, true)
+		}
+	})
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_rst_linux.go b/transport/internet/finalmask/rawpacket/spoof_rst_linux.go
new file mode 100644
index 000000000000..a87d2bb82296
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_rst_linux.go
@@ -0,0 +1,42 @@
+package rawpacket
+
+import (
+	"log"
+	"os/exec"
+	"strconv"
+)
+
+// suppressKernelRST installs an iptables rule that drops the kernel's
+// RST replies for the relay listen port (the fake TCP handshake has no
+// kernel socket behind it, so the kernel would answer our own SYN with
+// RST). Only RSTs matching the relay port are dropped; the raw socket's
+// spoofed packets are unaffected. Returns true when the rule was
+// installed.
+func suppressKernelRST(port uint16) bool {
+	if port == 0 {
+		return false
+	}
+	rule := []string{"-I", "OUTPUT", "-p", "tcp", "--tcp-flags", "RST", "RST", "--sport", strconv.Itoa(int(port)), "-j", "DROP"}
+	err := exec.Command("iptables", rule...).Run()
+	if err != nil {
+		log.Printf("[rawpacket] failed to suppress kernel RST on port %d: %v", port, err)
+		return false
+	}
+	log.Printf("[rawpacket] suppressed kernel RST on port %d", port)
+	return true
+}
+
+// restoreKernelRST removes the rule installed by suppressKernelRST.
+// managed must be the value returned by suppressKernelRST.
+func restoreKernelRST(port uint16, managed bool) {
+	if !managed || port == 0 {
+		return
+	}
+	rule := []string{"-D", "OUTPUT", "-p", "tcp", "--tcp-flags", "RST", "RST", "--sport", strconv.Itoa(int(port)), "-j", "DROP"}
+	err := exec.Command("iptables", rule...).Run()
+	if err != nil {
+		log.Printf("[rawpacket] failed to restore kernel RST on port %d: %v", port, err)
+		return
+	}
+	log.Printf("[rawpacket] restored kernel RST on port %d", port)
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_rst_stub.go b/transport/internet/finalmask/rawpacket/spoof_rst_stub.go
new file mode 100644
index 000000000000..337542156a84
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_rst_stub.go
@@ -0,0 +1,17 @@
+//go:build !linux
+
+package rawpacket
+
+import "log"
+
+// suppressKernelRST is a no-op off Linux: the kernel only emits RST
+// replies on the host that owns the port, and raw sockets are privileged
+// there anyway. Return false so the caller knows no rule is managed.
+func suppressKernelRST(port uint16) bool {
+	if port != 0 {
+		log.Printf("[rawpacket] kernel RST suppression only supported on linux (port %d left as-is)", port)
+	}
+	return false
+}
+
+func restoreKernelRST(port uint16, managed bool) {}
diff --git a/transport/internet/finalmask/rawpacket/spoof_sender.go b/transport/internet/finalmask/rawpacket/spoof_sender.go
new file mode 100644
index 000000000000..ea4066e35905
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_sender.go
@@ -0,0 +1,217 @@
+package rawpacket
+
+import (
+	"math/rand"
+	"net/netip"
+	"sync"
+)
+
+type tcpSender struct {
+	srcIP   netip.Addr
+	srcPort uint16
+	ttl     uint8
+	ipID    uint16
+	server  bool
+	fd      *rawSendFD
+	mu      sync.Mutex
+}
+
+func newTCPSender(cfg *SpoofSenderConfig) (*tcpSender, error) {
+	ips := cfg.SourceIPs
+	if len(ips) == 0 {
+		ips = []netip.Addr{cfg.SourceIP}
+	}
+	fd, err := openRawSender(ips[0])
+	if err != nil {
+		return nil, err
+	}
+	return &tcpSender{
+		srcIP:   ips[0],
+		srcPort: cfg.SourcePort,
+		ttl:     cfg.TTL,
+		ipID:    uint16(rand.Intn(65535)),
+		server:  cfg.Server,
+		fd:      fd,
+	}, nil
+}
+
+func (s *tcpSender) nextIPID() uint16 {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.ipID++
+	return s.ipID
+}
+
+func (s *tcpSender) Send(payload []byte, dstIP netip.Addr, dstPort uint16, tcp *TCPSimState) error {
+	if tcp == nil {
+		return nil
+	}
+	seq := tcp.nextSeq(len(payload))
+	var flags uint8
+	if s.server {
+		flags = tcp.serverFlags()
+	} else {
+		flags = tcp.clientFlags()
+	}
+	pkt := BuildTCPPacket(s.srcIP, dstIP, s.srcPort, dstPort, seq, tcp.ack(), flags, payload, s.ttl, s.nextIPID(), flags&TCPFlagSyn != 0)
+	return s.fd.send(pkt)
+}
+
+func (s *tcpSender) Close() error {
+	if s.fd != nil {
+		s.fd.close()
+	}
+	return nil
+}
+
+type udpSender struct {
+	srcIP   netip.Addr
+	srcPort uint16
+	ttl     uint8
+	ipID    uint16
+	fd      *rawSendFD
+	mu      sync.Mutex
+}
+
+func newUDPSender(cfg *SpoofSenderConfig) (*udpSender, error) {
+	ips := cfg.SourceIPs
+	if len(ips) == 0 {
+		ips = []netip.Addr{cfg.SourceIP}
+	}
+	fd, err := openRawSender(ips[0])
+	if err != nil {
+		return nil, err
+	}
+	return &udpSender{
+		srcIP:   ips[0],
+		srcPort: cfg.SourcePort,
+		ttl:     cfg.TTL,
+		ipID:    uint16(rand.Intn(65535)),
+		fd:      fd,
+	}, nil
+}
+
+func (s *udpSender) nextIPID() uint16 {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.ipID++
+	return s.ipID
+}
+
+func (s *udpSender) Send(payload []byte, dstIP netip.Addr, dstPort uint16, tcp *TCPSimState) error {
+	pkt := BuildRawUDP(s.srcIP, dstIP, s.srcPort, dstPort, payload, s.ttl, s.nextIPID())
+	return s.fd.send(pkt)
+}
+
+func (s *udpSender) Close() error {
+	if s.fd != nil {
+		s.fd.close()
+	}
+	return nil
+}
+
+type icmpSender struct {
+	srcIP netip.Addr
+	id    uint16
+	seq   uint16
+	ttl   uint8
+	ipID  uint16
+	seqMu sync.Mutex
+	fd    *rawSendFD
+}
+
+func newICMPSender(cfg *SpoofSenderConfig) (*icmpSender, error) {
+	ips := cfg.SourceIPs
+	if len(ips) == 0 {
+		ips = []netip.Addr{cfg.SourceIP}
+	}
+	fd, err := openRawSender(ips[0])
+	if err != nil {
+		return nil, err
+	}
+	return &icmpSender{
+		srcIP: ips[0],
+		id:    cfg.SourcePort,
+		seq:   1,
+		ttl:   cfg.TTL,
+		ipID:  uint16(rand.Intn(65535)),
+		fd:    fd,
+	}, nil
+}
+
+func (s *icmpSender) nextIPID() uint16 {
+	s.seqMu.Lock()
+	defer s.seqMu.Unlock()
+	s.ipID++
+	return s.ipID
+}
+
+func (s *icmpSender) Send(payload []byte, dstIP netip.Addr, dstPort uint16, tcp *TCPSimState) error {
+	s.seqMu.Lock()
+	seq := s.seq
+	s.seq++
+	s.seqMu.Unlock()
+
+	pkt := BuildICMPv4Echo(s.srcIP, dstIP, s.id, seq, payload, s.ttl, s.nextIPID())
+	return s.fd.send(pkt)
+}
+
+func (s *icmpSender) Close() error {
+	if s.fd != nil {
+		s.fd.close()
+	}
+	return nil
+}
+
+type icmpv6Sender struct {
+	srcIP netip.Addr
+	id    uint16
+	seq   uint16
+	ttl   uint8
+	ipID  uint16
+	seqMu sync.Mutex
+	fd    *rawSendFD
+}
+
+func newICMPv6Sender(cfg *SpoofSenderConfig) (*icmpv6Sender, error) {
+	ips := cfg.SourceIPs
+	if len(ips) == 0 {
+		ips = []netip.Addr{cfg.SourceIP}
+	}
+	fd, err := openRawSender(ips[0])
+	if err != nil {
+		return nil, err
+	}
+	return &icmpv6Sender{
+		srcIP: ips[0],
+		id:    cfg.SourcePort,
+		seq:   1,
+		ttl:   cfg.TTL,
+		ipID:  uint16(rand.Intn(65535)),
+		fd:    fd,
+	}, nil
+}
+
+func (s *icmpv6Sender) nextIPID() uint16 {
+	s.seqMu.Lock()
+	defer s.seqMu.Unlock()
+	s.ipID++
+	return s.ipID
+}
+
+func (s *icmpv6Sender) Send(payload []byte, dstIP netip.Addr, dstPort uint16, tcp *TCPSimState) error {
+	s.seqMu.Lock()
+	seq := s.seq
+	s.seq++
+	s.seqMu.Unlock()
+
+	pkt := BuildICMPv6Echo(s.srcIP, dstIP, s.id, seq, payload, s.ttl, s.nextIPID())
+	return s.fd.send(pkt)
+}
+
+func (s *icmpv6Sender) Close() error {
+	if s.fd != nil {
+		s.fd.close()
+	}
+	return nil
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_session.go b/transport/internet/finalmask/rawpacket/spoof_session.go
new file mode 100644
index 000000000000..cbfdef817006
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_session.go
@@ -0,0 +1,85 @@
+package rawpacket
+
+import (
+	"net"
+	"net/netip"
+	"sync"
+	"time"
+)
+
+type RelaySession struct {
+	ID         [8]byte
+	ClientIP   netip.Addr
+	ClientPort uint16
+	TargetConn net.Conn
+	crypto     *frameCrypto
+	tcp        *TCPSimState
+	LastSeen   time.Time
+	mu         sync.Mutex
+	closed     bool
+}
+
+type SessionManager struct {
+	sessions map[[8]byte]*RelaySession
+	mu       sync.Mutex
+}
+
+func NewSessionManager() *SessionManager {
+	return &SessionManager{
+		sessions: make(map[[8]byte]*RelaySession),
+	}
+}
+
+func (sm *SessionManager) Add(id [8]byte, clientIP netip.Addr, clientPort uint16, targetConn net.Conn, crypto *frameCrypto, tcp *TCPSimState) *RelaySession {
+	sm.mu.Lock()
+	defer sm.mu.Unlock()
+	s := &RelaySession{
+		ID:         id,
+		ClientIP:   clientIP,
+		ClientPort: clientPort,
+		TargetConn: targetConn,
+		crypto:     crypto,
+		tcp:        tcp,
+		LastSeen:   time.Now(),
+	}
+	sm.sessions[id] = s
+	return s
+}
+
+func (sm *SessionManager) Get(id [8]byte) *RelaySession {
+	sm.mu.Lock()
+	defer sm.mu.Unlock()
+	return sm.sessions[id]
+}
+
+// Remove is idempotent: it closes the target connection, marks the
+// session closed and drops it from the map.
+func (sm *SessionManager) Remove(id [8]byte) {
+	sm.mu.Lock()
+	defer sm.mu.Unlock()
+	if s, ok := sm.sessions[id]; ok {
+		s.closed = true
+		s.TargetConn.Close()
+		delete(sm.sessions, id)
+	}
+}
+
+func (sm *SessionManager) All() []*RelaySession {
+	sm.mu.Lock()
+	defer sm.mu.Unlock()
+	out := make([]*RelaySession, 0, len(sm.sessions))
+	for _, s := range sm.sessions {
+		out = append(out, s)
+	}
+	return out
+}
+
+func (sm *SessionManager) Close() {
+	sm.mu.Lock()
+	defer sm.mu.Unlock()
+	for _, s := range sm.sessions {
+		s.closed = true
+		s.TargetConn.Close()
+	}
+	clear(sm.sessions)
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_source_ip.go b/transport/internet/finalmask/rawpacket/spoof_source_ip.go
new file mode 100644
index 000000000000..58a232a6093f
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_source_ip.go
@@ -0,0 +1,33 @@
+package rawpacket
+
+import (
+	"net/netip"
+	"sync/atomic"
+)
+
+type SourceIPRotator struct {
+	ips  []netip.Addr
+	next atomic.Uint64
+}
+
+func NewSourceIPRotator(ips []netip.Addr) *SourceIPRotator {
+	if len(ips) == 0 {
+		return nil
+	}
+	return &SourceIPRotator{ips: ips}
+}
+
+func (r *SourceIPRotator) Next() netip.Addr {
+	if r == nil || len(r.ips) == 0 {
+		return netip.Addr{}
+	}
+	i := r.next.Add(1) - 1
+	return r.ips[i%uint64(len(r.ips))]
+}
+
+func (r *SourceIPRotator) Len() int {
+	if r == nil {
+		return 0
+	}
+	return len(r.ips)
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_tcp.go b/transport/internet/finalmask/rawpacket/spoof_tcp.go
new file mode 100644
index 000000000000..2cfe21ef0b57
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_tcp.go
@@ -0,0 +1,254 @@
+package rawpacket
+
+import (
+	"encoding/binary"
+	"net/netip"
+)
+
+const (
+	tcpMaxSegmentMSS = 1460
+	tcpWindowScale   = 7
+)
+
+// tcpOptions builds the TCP options for an outbound segment. SYN segments
+// carry MSS/SACK-permitted/TS/WScale like Linux; data segments keep the
+// timestamp option (RFC 7323 requires it on every segment once
+// negotiated). Header size: 20 bytes for SYN, 12 for data.
+func tcpOptions(syn bool, ts uint32, tsecr uint32) []byte {
+	if syn {
+		opt := make([]byte, 0, 20)
+		opt = append(opt, 2, 4, byte(tcpMaxSegmentMSS>>8), byte(tcpMaxSegmentMSS&0xff)) // MSS
+		opt = append(opt, 4, 2)                                                         // SACK permitted
+		opt = append(opt, 8, 10)                                                        // TS
+		opt = binary.BigEndian.AppendUint32(opt, ts)
+		opt = binary.BigEndian.AppendUint32(opt, tsecr)
+		opt = append(opt, 1) // NOP
+		opt = append(opt, 3, 3, tcpWindowScale)
+		return opt
+	}
+	opt := make([]byte, 0, 12)
+	opt = append(opt, 1, 1, 8, 10)
+	opt = binary.BigEndian.AppendUint32(opt, ts)
+	opt = binary.BigEndian.AppendUint32(opt, tsecr)
+	return opt
+}
+
+// BuildTCPPacket builds a TCP segment over IPv4 with plausible options,
+// DF set, and a caller-provided (monotonic) IP ID.
+func BuildTCPPacket(srcIP, dstIP netip.Addr, srcPort, dstPort uint16, seqNum, ackNum uint32, flags uint8, payload []byte, ttl uint8, ipID uint16, syn bool) []byte {
+	opts := tcpOptions(syn, tsVal(), 0)
+	tcpHdrLen := 20 + len(opts)
+	totalLen := 20 + tcpHdrLen + len(payload)
+
+	frame := make([]byte, totalLen)
+	ip := BuildIPv4Header(uint16(totalLen), ipID, ttl, 6, srcIP, dstIP, true)
+	copy(frame, ip)
+
+	tcp := frame[20:]
+	binary.BigEndian.PutUint16(tcp[0:], srcPort)
+	binary.BigEndian.PutUint16(tcp[2:], dstPort)
+	binary.BigEndian.PutUint32(tcp[4:], seqNum)
+	binary.BigEndian.PutUint32(tcp[8:], ackNum)
+	tcp[12] = byte((tcpHdrLen / 4) << 4)
+	tcp[13] = flags
+	binary.BigEndian.PutUint16(tcp[14:], 65535)
+
+	copy(tcp[20:], opts)
+	if len(payload) > 0 {
+		copy(tcp[tcpHdrLen:], payload)
+	}
+
+	pseudo := IPv4PseudoHeaderChecksum(srcIP, dstIP, 6, uint16(tcpHdrLen+len(payload)))
+	csum := Checksum(tcp[:tcpHdrLen+len(payload)], pseudo)
+	binary.BigEndian.PutUint16(tcp[16:], ^csum)
+
+	return frame
+}
+
+func BuildICMPv4Echo(srcIP, dstIP netip.Addr, id, seq uint16, payload []byte, ttl uint8, ipID uint16) []byte {
+	totalLen := 20 + 8 + len(payload)
+	frame := make([]byte, totalLen)
+	ip := BuildIPv4Header(uint16(totalLen), ipID, ttl, 1, srcIP, dstIP, false)
+	copy(frame, ip)
+
+	icmp := frame[20:]
+	icmp[0] = 8 // Echo Request
+	icmp[1] = 0
+	binary.BigEndian.PutUint16(icmp[4:], id)
+	binary.BigEndian.PutUint16(icmp[6:], seq)
+	copy(icmp[8:], payload)
+
+	// ICMP checksum covers ICMP header + payload
+	csum := Checksum(icmp[:8+len(payload)], 0)
+	binary.BigEndian.PutUint16(icmp[2:], ^csum)
+	return frame
+}
+
+func BuildICMPv6Echo(srcIP, dstIP netip.Addr, id, seq uint16, payload []byte, ttl uint8, ipID uint16) []byte {
+	// Non-standard: ICMPv6 Echo Request (type 128) over IPv4 header with protocol 58.
+	icmpLen := 8 + len(payload)
+	totalLen := 20 + icmpLen
+	frame := make([]byte, totalLen)
+	ip := BuildIPv4Header(uint16(totalLen), ipID, ttl, 58, srcIP, dstIP, false)
+	copy(frame, ip)
+
+	icmp := frame[20:]
+	icmp[0] = 128 // Echo Request
+	icmp[1] = 0
+	binary.BigEndian.PutUint16(icmp[4:], id)
+	binary.BigEndian.PutUint16(icmp[6:], seq)
+	copy(icmp[8:], payload)
+
+	// ICMPv6 checksum with IPv4 pseudo-header (protocol 58)
+	pseudo := IPv4PseudoHeaderChecksum(srcIP, dstIP, 58, uint16(icmpLen))
+	csum := Checksum(icmp[:icmpLen], pseudo)
+	binary.BigEndian.PutUint16(icmp[2:], ^csum)
+	return frame
+}
+
+func BuildRawUDP(srcIP, dstIP netip.Addr, srcPort, dstPort uint16, payload []byte, ttl uint8, ipID uint16) []byte {
+	ipHdrLen := 20
+	udpHdrLen := 8
+	totalLen := ipHdrLen + udpHdrLen + len(payload)
+
+	frame := make([]byte, totalLen)
+	ip := BuildIPv4Header(uint16(totalLen), ipID, ttl, 17, srcIP, dstIP, false)
+	copy(frame, ip)
+
+	udp := frame[ipHdrLen:]
+	binary.BigEndian.PutUint16(udp[0:], srcPort)
+	binary.BigEndian.PutUint16(udp[2:], dstPort)
+	udpLen := uint16(udpHdrLen + len(payload))
+	binary.BigEndian.PutUint16(udp[4:], udpLen)
+	binary.BigEndian.PutUint16(udp[6:], 0) // checksum = 0 (optional in IPv4)
+
+	if len(payload) > 0 {
+		copy(frame[ipHdrLen+udpHdrLen:], payload)
+	}
+
+	return frame
+}
+
+func ParseSrcIP(buf []byte, isV6 bool) (netip.Addr, netip.Addr, bool) {
+	if len(buf) < 20 {
+		return netip.Addr{}, netip.Addr{}, false
+	}
+	if buf[0]>>4 != 4 {
+		return netip.Addr{}, netip.Addr{}, false
+	}
+	src, _ := netip.AddrFromSlice(buf[12:16])
+	dst, _ := netip.AddrFromSlice(buf[16:20])
+	return src, dst, true
+}
+
+func ParseRawTCPPacket(buf []byte) (seq uint32, flags uint8, payload []byte, srcIP netip.Addr, dstIP netip.Addr, srcPort, dstPort uint16, ok bool) {
+	if len(buf) < 40 {
+		return
+	}
+	if buf[0]>>4 != 4 {
+		return
+	}
+	ihl := (buf[0] & 0x0f) * 4
+	if int(ihl) < 20 || int(ihl)+20 > len(buf) {
+		return
+	}
+	if buf[9] != 6 {
+		return
+	}
+	srcIP, _ = netip.AddrFromSlice(buf[12:16])
+	dstIP, _ = netip.AddrFromSlice(buf[16:20])
+	tcp := buf[ihl:]
+	seq = binary.BigEndian.Uint32(tcp[4:])
+	flags = tcp[13]
+	srcPort = binary.BigEndian.Uint16(tcp[0:])
+	dstPort = binary.BigEndian.Uint16(tcp[2:])
+	do := int((tcp[12] >> 4) * 4)
+	ihlInt := int(ihl)
+	if do < 20 || ihlInt+do > len(buf) {
+		return
+	}
+	payload = buf[ihlInt+do:]
+	ok = true
+	return
+}
+
+func ParseUDPPacket(buf []byte) (payload []byte, srcPort, dstPort uint16, ok bool) {
+	if len(buf) < 28 {
+		return
+	}
+	ihl := (buf[0] & 0x0f) * 4
+	if int(ihl) < 20 {
+		return
+	}
+	if buf[9] != 17 {
+		return
+	}
+	udp := buf[ihl:]
+	srcPort = binary.BigEndian.Uint16(udp[0:])
+	dstPort = binary.BigEndian.Uint16(udp[2:])
+	udpLen := int(binary.BigEndian.Uint16(udp[4:]))
+	if udpLen < 8 || int(ihl)+udpLen > len(buf) {
+		return
+	}
+	payload = udp[8:udpLen]
+	ok = true
+	return
+}
+
+func ParseICMPv4Echo(buf []byte) (id, seq uint16, payload []byte, ok bool) {
+	if len(buf) < 28 {
+		return
+	}
+	ihl := (buf[0] & 0x0f) * 4
+	if int(ihl) < 20 {
+		return
+	}
+	if buf[9] != 1 {
+		return
+	}
+	icmp := buf[ihl:]
+	if len(icmp) < 8 {
+		return
+	}
+	if icmp[0] != 8 {
+		return
+	}
+	id = binary.BigEndian.Uint16(icmp[4:])
+	seq = binary.BigEndian.Uint16(icmp[6:])
+	payload = icmp[8:]
+	ok = true
+	return
+}
+
+func ParseICMPv6Echo(buf []byte) (id, seq uint16, payload []byte, ok bool) {
+	if len(buf) < 28 {
+		return
+	}
+	var hdrLen int
+	switch buf[0] >> 4 {
+	case 4:
+		if buf[9] != 58 {
+			return
+		}
+		hdrLen = int(buf[0]&0x0f) * 4
+	case 6:
+		if buf[6] != 58 {
+			return
+		}
+		hdrLen = 40
+	default:
+		return
+	}
+	if hdrLen < 20 || len(buf) < hdrLen+8 {
+		return
+	}
+	icmp := buf[hdrLen:]
+	if icmp[0] != 128 {
+		return
+	}
+	id = binary.BigEndian.Uint16(icmp[4:])
+	seq = binary.BigEndian.Uint16(icmp[6:])
+	payload = icmp[8:]
+	ok = true
+	return
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_tcp_test.go b/transport/internet/finalmask/rawpacket/spoof_tcp_test.go
new file mode 100644
index 000000000000..613426462b93
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_tcp_test.go
@@ -0,0 +1,159 @@
+package rawpacket
+
+import (
+	"net/netip"
+	"testing"
+)
+
+func TestTCPSimStateClient(t *testing.T) {
+	st := newTCPSimState()
+	if st.clientFlags() != TCPFlagSyn {
+		t.Fatalf("first client segment should be SYN, got %#x", st.clientFlags())
+	}
+	seq := st.nextSeq(100)
+	if seq != st.isn {
+		t.Fatalf("first data seq should be ISN, got %d want %d", seq, st.isn)
+	}
+	if st.clientFlags() != TCPFlagAck {
+		t.Fatalf("second client segment should be ACK, got %#x", st.clientFlags())
+	}
+	if got := st.ack(); got != 0 {
+		t.Fatalf("ack before observing peer should be 0, got %d", got)
+	}
+	// peer handshake: SYN consumes one byte, then 500 bytes of data
+	st.observePeer(1000, 0)
+	if st.ack() != 1001 {
+		t.Fatalf("ack after peer SYN should be seq+1, got %d want 1001", st.ack())
+	}
+	st.observePeer(1001, 500)
+	if st.ack() != 1501 {
+		t.Fatalf("ack should be peer seq+len+1, got %d want 1501", st.ack())
+	}
+	// zero-length segments (keepalives) must not advance the sequence
+	if st.nextSeq(0) != st.isn+100 {
+		t.Fatalf("zero-length segment advanced seq: got %d want %d", st.nextSeq(0), st.isn+100)
+	}
+	// nextSeq returns the segment's own seq (pre-advance)
+	if got := st.nextSeq(10); got != st.isn+100 {
+		t.Fatalf("data after keepalive should be isn+100, got %d", got)
+	}
+	if got := st.nextSeq(1); got != st.isn+110 {
+		t.Fatalf("next segment should be isn+110, got %d", got)
+	}
+}
+
+func TestTCPSimStateServer(t *testing.T) {
+	st := newTCPSimState()
+	if st.serverFlags() != TCPFlagSyn|TCPFlagAck {
+		t.Fatalf("first server segment should be SYN|ACK, got %#x", st.serverFlags())
+	}
+	if st.serverFlags() != TCPFlagAck {
+		t.Fatalf("second server segment should be ACK, got %#x", st.serverFlags())
+	}
+	st.observeClientSeq(777, 0)
+	if st.ack() != 778 {
+		t.Fatalf("server ack should be observed client seq+1, got %d want 778", st.ack())
+	}
+	st.observeClientSeq(778, 20)
+	if st.ack() != 798 {
+		t.Fatalf("server ack should advance by payload length, got %d want 798", st.ack())
+	}
+	seq := st.nextSeq(50)
+	if seq != st.isn {
+		t.Fatalf("server data should start at its ISN, got %d", seq)
+	}
+	if got := st.nextSeq(30); got != st.isn+50 {
+		t.Fatalf("server second segment should be isn+50, got %d", got)
+	}
+}
+
+func TestBuildTCPPacketOptionsAndFlags(t *testing.T) {
+	src := netip.MustParseAddr("1.2.3.4")
+	dst := netip.MustParseAddr("5.6.7.8")
+	st := newTCPSimState()
+
+	// SYN segment: 20 ip + 20 tcp + 20 options
+	syn := BuildTCPPacket(src, dst, 12345, 443, st.isn, 0, TCPFlagSyn, nil, 64, 100, true)
+	if len(syn) != 20+40 {
+		t.Fatalf("SYN should be 60 bytes (20 ip + 40 tcp w/ 20 opts), got %d", len(syn))
+	}
+	if syn[0]>>4 != 4 {
+		t.Fatalf("not IPv4: %#x", syn[0])
+	}
+	// DF bit set
+	if syn[6]&0x40 == 0 {
+		t.Fatal("DF bit not set")
+	}
+	// IP ID
+	if id := uint16(syn[4])<<8 | uint16(syn[5]); id != 100 {
+		t.Fatalf("IP ID = %d, want 100", id)
+	}
+	// data offset: 40 bytes tcp => 10 words
+	if syn[32]>>4 != 10 {
+		t.Fatalf("TCP data offset = %d, want 10", syn[32]>>4)
+	}
+	// MSS option at offset 20
+	if syn[40] != 2 || syn[41] != 4 {
+		t.Fatal("MSS option kind not found")
+	}
+	if mss := uint16(syn[42])<<8 | uint16(syn[43]); mss != tcpMaxSegmentMSS {
+		t.Fatalf("MSS = %d, want %d", mss, tcpMaxSegmentMSS)
+	}
+	// checksum sanity: valid checksum means header verifies
+	checkTCPChecksum(t, syn)
+
+	// data segment: ACK only, 12-byte options
+	payload := make([]byte, 100)
+	data := BuildTCPPacket(src, dst, 12345, 443, st.isn, 1000, TCPFlagAck, payload, 64, 101, false)
+	if len(data) != 20+32+100 {
+		t.Fatalf("data seg should be 152 bytes, got %d", len(data))
+	}
+	if data[32]>>4 != 8 {
+		t.Fatalf("data offset = %d, want 8", data[32]>>4)
+	}
+	if data[40] != 1 || data[41] != 1 || data[42] != 8 || data[43] != 10 {
+		t.Fatal("data segment should carry NOP NOP TS options")
+	}
+	checkTCPChecksum(t, data)
+}
+
+func checkTCPChecksum(t *testing.T, pkt []byte) {
+	t.Helper()
+	pseudo := IPv4PseudoHeaderChecksum(
+		netip.AddrFrom4([4]byte{pkt[12], pkt[13], pkt[14], pkt[15]}),
+		netip.AddrFrom4([4]byte{pkt[16], pkt[17], pkt[18], pkt[19]}),
+		pkt[9],
+		uint16(len(pkt)-20),
+	)
+	if csum := Checksum(pkt[20:], pseudo); csum != 0xffff {
+		t.Fatalf("TCP checksum invalid: %#x", csum)
+	}
+}
+
+func TestMaxPayloadForMTU(t *testing.T) {
+	if got := maxPayloadForMTU(0); got != frameMaxPayload {
+		t.Fatalf("default should be frameMaxPayload, got %d", got)
+	}
+	if got := maxPayloadForMTU(1500); got != 1500-20-40-frameOverhead {
+		t.Fatalf("1500 MTU: got %d", got)
+	}
+	if got := maxPayloadForMTU(100); got < 1 {
+		t.Fatalf("tiny MTU should clamp to >= 1, got %d", got)
+	}
+	if got := maxPayloadForMTU(1 << 20); got != frameMaxPayload {
+		t.Fatalf("huge MTU should cap at frameMaxPayload, got %d", got)
+	}
+}
+
+func TestBuildTCPPacketIPIDMonotonic(t *testing.T) {
+	src := netip.MustParseAddr("1.2.3.4")
+	dst := netip.MustParseAddr("5.6.7.8")
+	prev := uint16(65000)
+	for i := 0; i < 100; i++ {
+		prev++
+		pkt := BuildTCPPacket(src, dst, 1, 443, 1, 1, TCPFlagAck, nil, 64, prev, false)
+		if id := uint16(pkt[4])<<8 | uint16(pkt[5]); id != prev {
+			t.Fatalf("IP ID = %d, want %d", id, prev)
+		}
+	}
+}
diff --git a/transport/internet/finalmask/rawpacket/spoof_transport.go b/transport/internet/finalmask/rawpacket/spoof_transport.go
new file mode 100644
index 000000000000..116e07cbc4f5
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/spoof_transport.go
@@ -0,0 +1,69 @@
+package rawpacket
+
+import "net/netip"
+
+type SpoofSender interface {
+	Send(payload []byte, dstIP netip.Addr, dstPort uint16, tcp *TCPSimState) error
+	Close() error
+}
+
+// TCPMeta carries the header fields of a received raw packet so the
+// caller can keep the fake conversation's sequence/ack state plausible,
+// and the relay can masquerade replies from the address the probe dialed.
+// DstIP/DstPort are always set; Seq/Flags are non-zero only for TCP.
+// nil for transports the receiver does not describe (ICMP).
+type TCPMeta struct {
+	Seq     uint32
+	Flags   uint8
+	DstIP   netip.Addr
+	DstPort uint16
+}
+
+type SpoofReceiver interface {
+	Receive() (payload []byte, srcIP netip.Addr, srcPort uint16, tcp *TCPMeta, err error)
+	Close() error
+}
+
+func NewSender(transport string, cfg *SpoofSenderConfig) (SpoofSender, error) {
+	switch transport {
+	case "tcp", "":
+		return newTCPSender(cfg)
+	case "udp":
+		return newUDPSender(cfg)
+	case "icmp":
+		return newICMPSender(cfg)
+	case "icmpv6":
+		return newICMPv6Sender(cfg)
+	}
+	return nil, nil
+}
+
+func NewReceiver(transport string, cfg *SpoofReceiverConfig) (SpoofReceiver, error) {
+	switch transport {
+	case "tcp", "":
+		return newTCPReceiver(cfg)
+	case "udp":
+		return newUDPReceiver(cfg)
+	case "icmp":
+		return newICMPReceiver(cfg)
+	case "icmpv6":
+		return newICMPv6Receiver(cfg)
+	}
+	return nil, nil
+}
+
+type SpoofSenderConfig struct {
+	SourceIP   netip.Addr
+	SourceIPs  []netip.Addr
+	SourcePort uint16
+	TTL        uint8
+	// Server marks a relay-side sender: outbound TCP segments take the
+	// passive-opener role (SYN|ACK then ACK).
+	Server bool
+}
+
+type SpoofReceiverConfig struct {
+	ListenPort  uint16
+	PeerSpoofIP netip.Addr
+	BufferSize  int
+}
diff --git a/transport/internet/finalmask/rawpacket/tcp_state.go b/transport/internet/finalmask/rawpacket/tcp_state.go
new file mode 100644
index 000000000000..a8ad3014363f
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/tcp_state.go
@@ -0,0 +1,118 @@
+package rawpacket
+
+import (
+	"math/rand"
+	"sync"
+	"time"
+)
+
+// TCPSimState simulates a plausible TCP conversation between the client
+// and the relay so middleboxes see a normal connection: SYN with TCP
+// options, then ACK segments with monotonically increasing sequence
+// numbers and correct acknowledgements.
+//
+// The client and the relay each keep one state per tunnel session.
+// The client is the "active opener" (sends SYN, then ACKs), the relay is
+// the "passive opener" (replies SYN|ACK, then ACKs). Which role a state
+// plays is decided by the first outbound segment: client role sends a
+// bare SYN, server role sends SYN|ACK.
+type TCPSimState struct {
+	mu       sync.Mutex
+	isn      uint32 // our initial sequence number
+	seq      uint32 // next sequence number to send
+	synSent  bool   // our SYN (or SYN|ACK) has been sent
+	peerISN  uint32 // peer's initial sequence number
+	peerSeq  uint32 // peer's next expected sequence number (peer's last seq + 1)
+	peerSeen bool
+}
+
+func newTCPSimState() *TCPSimState {
+	isn := uint32(rand.Int63n(1 << 31))
+	return &TCPSimState{isn: isn, seq: isn}
+}
+
+// nextSeq returns the sequence number to use for an outbound segment of
+// the given payload length and advances the counter. Zero-length segments
+// (keepalives) do not consume sequence numbers.
+func (s *TCPSimState) nextSeq(payloadLen int) uint32 {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	seq := s.seq
+	if payloadLen > 0 {
+		s.seq += uint32(payloadLen)
+	}
+	return seq
+}
+
+// flags returns the flags for the next outbound segment in client role.
+func (s *TCPSimState) clientFlags() uint8 {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.synSent {
+		s.synSent = true
+		return TCPFlagSyn
+	}
+	return TCPFlagAck
+}
+
+// flags returns the flags for the next outbound segment in server role.
+func (s *TCPSimState) serverFlags() uint8 {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.synSent {
+		s.synSent = true
+		return TCPFlagSyn | TCPFlagAck
+	}
+	return TCPFlagAck
+}
+
+// ack returns the acknowledgement number for the next outbound segment:
+// the peer's last seen sequence number plus one, or zero before the peer
+// is seen.
+func (s *TCPSimState) ack() uint32 {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.peerSeen {
+		return 0
+	}
+	return s.peerSeq
+}
+
+// observePeer records the peer's latest segment (its wire sequence number
+// and payload length) so outbound acknowledgements stay plausible. The
+// first segment is the peer's SYN and consumes one byte; later segments
+// advance by their payload length only.
+func (s *TCPSimState) observePeer(seq uint32, payloadLen int) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.peerSeen {
+		s.peerSeen = true
+		s.peerISN = seq
+		s.peerSeq = seq + 1 + uint32(payloadLen)
+		return
+	}
+	s.peerSeq = seq + uint32(payloadLen)
+}
+
+// observeClientSeq records the client's latest wire sequence number so
+// server-role acknowledgements are correct. Used on the relay, where the
+// client's cumulative sequence is already encoded in the wire seq. The
+// first segment (the client's SYN) consumes one byte; later segments
+// advance by their payload length only.
+func (s *TCPSimState) observeClientSeq(seq uint32, payloadLen int) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.peerSeen {
+		s.peerSeen = true
+		s.peerISN = seq
+		s.peerSeq = seq + 1 + uint32(payloadLen)
+		return
+	}
+	s.peerSeq = seq + uint32(payloadLen)
+}
+
+// tsVal returns a plausible TCP timestamp value: milliseconds since a
+// fixed epoch, so it grows monotonically like Linux jiffies.
+func tsVal() uint32 {
+	return uint32(time.Now().UnixMilli() & 0xFFFFFFFF)
+}
diff --git a/transport/internet/finalmask/rawpacket/tcpip.go b/transport/internet/finalmask/rawpacket/tcpip.go
new file mode 100644
index 000000000000..bd00a28c0112
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/tcpip.go
@@ -0,0 +1,196 @@
+package rawpacket
+
+import (
+	"encoding/binary"
+	"net/netip"
+)
+
+const (
+	IPv4MinimumSize   = 20
+	IPv6MinimumSize   = 40
+	TCPMinimumSize    = 20
+	TCPProtocolNumber = 6
+
+	TCPOptionEOL      = 0
+	TCPOptionNOP      = 1
+	TCPOptionTS       = 8
+	TCPOptionTSLength = 10
+
+	TCPFlagFin = 0x01
+	TCPFlagSyn = 0x02
+	TCPFlagRst = 0x04
+	TCPFlagPsh = 0x08
+	TCPFlagAck = 0x10
+)
+
+func Checksum(data []byte, initial uint16) uint16 {
+	var csum uint32 = uint32(initial)
+	for i := 0; i < len(data)-1; i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(data[i:]))
+	}
+	if len(data)%2 == 1 {
+		csum += uint32(data[len(data)-1]) << 8
+	}
+	for csum > 0xffff {
+		csum = (csum >> 16) + (csum & 0xffff)
+	}
+	return uint16(csum)
+}
+
+func PseudoHeaderChecksum(protocol uint8, srcAddr, dstAddr []byte, totalLen uint16) uint16 {
+	var csum uint32
+	for i := 0; i < len(srcAddr); i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(srcAddr[i:]))
+	}
+	for i := 0; i < len(dstAddr); i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(dstAddr[i:]))
+	}
+	csum += uint32(protocol)
+	csum += uint32(totalLen)
+	for csum > 0xffff {
+		csum = (csum >> 16) + (csum & 0xffff)
+	}
+	return uint16(csum)
+}
+
+func CombineChecksum(c1, c2 uint16) uint16 {
+	csum := uint32(c1) + uint32(c2)
+	for csum > 0xffff {
+		csum = (csum >> 16) + (csum & 0xffff)
+	}
+	return uint16(csum)
+}
+
+func EncodeTSOption(val uint32, ecr uint32, b []byte) {
+	b[0] = TCPOptionTS
+	b[1] = TCPOptionTSLength
+	binary.BigEndian.PutUint32(b[2:], val)
+	binary.BigEndian.PutUint32(b[6:], ecr)
+}
+
+func ParseTCPOptions(b []byte) (tsVal uint32, hasTS bool) {
+	for i := 0; i < len(b); {
+		if b[i] == TCPOptionEOL {
+			break
+		}
+		if b[i] == TCPOptionNOP {
+			i++
+			continue
+		}
+		if i+1 >= len(b) {
+			break
+		}
+		optLen := int(b[i+1])
+		if optLen < 2 || i+optLen > len(b) {
+			break
+		}
+		if b[i] == TCPOptionTS && optLen == TCPOptionTSLength {
+			return binary.BigEndian.Uint32(b[i+2:]), true
+		}
+		i += optLen
+	}
+	return 0, false
+}
+
+// IPv4 header representation
+type IPv4 []byte
+
+func (b IPv4) TotalLength() uint16    { return binary.BigEndian.Uint16(b[2:]) }
+func (b IPv4) Flags() uint8           { return uint8(binary.BigEndian.Uint16(b[6:]) >> 13) }
+func (b IPv4) FragmentOffset() uint16 { return binary.BigEndian.Uint16(b[6:]) & 0x1fff }
+func (b IPv4) Protocol() uint8        { return b[9] }
+func (b IPv4) HeaderLength() uint8    { return (b[0] & 0x0f) * 4 }
+func (b IPv4) ID() uint16             { return binary.BigEndian.Uint16(b[4:]) }
+func (b IPv4) Src() netip.Addr        { return netip.AddrFrom4([4]byte(b[12:16])) }
+func (b IPv4) Dst() netip.Addr        { return netip.AddrFrom4([4]byte(b[16:20])) }
+
+func (b IPv4) SetID(id uint16) {
+	binary.BigEndian.PutUint16(b[4:], id)
+}
+
+func (b IPv4) SetTotalLength(n uint16) {
+	binary.BigEndian.PutUint16(b[2:], n)
+}
+
+func (b IPv4) RecalcChecksum() {
+	binary.BigEndian.PutUint16(b[10:], 0)
+	csum := Checksum(b[:20], 0)
+	binary.BigEndian.PutUint16(b[10:], ^csum)
+}
+
+func (b IPv4) Encode(totalLength uint16, id uint16, ttl uint8, protocol uint8, src, dst netip.Addr) {
+	b[0] = (4 << 4) | 5 // IPv4, Header Length = 20
+	b[1] = 0            // TOS
+	binary.BigEndian.PutUint16(b[2:], totalLength)
+	binary.BigEndian.PutUint16(b[4:], id)
+	binary.BigEndian.PutUint16(b[6:], 0) // Flags and Fragment Offset
+	b[8] = ttl
+	b[9] = protocol
+	b[10] = 0 // Checksum (0 for calculation)
+	copy(b[12:16], src.AsSlice())
+	copy(b[16:20], dst.AsSlice())
+	csum := Checksum(b[:20], 0)
+	binary.BigEndian.PutUint16(b[10:], ^csum)
+}
+
+type IPv6 []byte
+
+func (b IPv6) PayloadLength() uint16    { return binary.BigEndian.Uint16(b[4:]) }
+func (b IPv6) TransportProtocol() uint8 { return b[6] }
+func (b IPv6) Src() netip.Addr          { return netip.AddrFrom16([16]byte(b[8:24])) }
+func (b IPv6) Dst() netip.Addr          { return netip.AddrFrom16([16]byte(b[24:40])) }
+
+func (b IPv6) SetPayloadLength(n uint16) {
+	binary.BigEndian.PutUint16(b[4:], n)
+}
+
+func (b IPv6) Encode(payloadLength uint16, transportProtocol uint8, hopLimit uint8, src, dst netip.Addr) {
+	binary.BigEndian.PutUint32(b[0:], 6<<28) // Version 6, Traffic Class 0, Flow Label 0
+	binary.BigEndian.PutUint16(b[4:], payloadLength)
+	b[6] = transportProtocol
+	b[7] = hopLimit
+	copy(b[8:24], src.AsSlice())
+	copy(b[24:40], dst.AsSlice())
+}
+
+type TCP []byte
+
+func (b TCP) DataOffset() uint8       { return (b[12] >> 4) * 4 }
+func (b TCP) SequenceNumber() uint32  { return binary.BigEndian.Uint32(b[4:]) }
+func (b TCP) AckNumber() uint32       { return binary.BigEndian.Uint32(b[8:]) }
+func (b TCP) Flags() uint8            { return b[13] }
+func (b TCP) WindowSize() uint16      { return binary.BigEndian.Uint16(b[14:]) }
+func (b TCP) Options() []byte         { return b[TCPMinimumSize:b.DataOffset()] }
+func (b TCP) SetChecksum(csum uint16) { binary.BigEndian.PutUint16(b[16:], csum) }
+
+func (b TCP) SetSequenceNumber(seq uint32) {
+	binary.BigEndian.PutUint32(b[4:], seq)
+}
+
+func (b TCP) SetAckNumber(ack uint32) {
+	binary.BigEndian.PutUint32(b[8:], ack)
+}
+
+func (b TCP) SetFlags(flags uint8) {
+	b[13] = flags
+}
+
+func (b TCP) SetWindowSize(wind uint16) {
+	binary.BigEndian.PutUint16(b[14:], wind)
+}
+
+func (b TCP) Encode(srcPort, dstPort uint16, seqNum, ackNum uint32, dataOffset uint8, flags uint8, windowSize uint16) {
+	binary.BigEndian.PutUint16(b[0:], srcPort)
+	binary.BigEndian.PutUint16(b[2:], dstPort)
+	binary.BigEndian.PutUint32(b[4:], seqNum)
+	binary.BigEndian.PutUint32(b[8:], ackNum)
+	b[12] = (dataOffset / 4) << 4
+	b[13] = flags
+	binary.BigEndian.PutUint16(b[14:], windowSize)
+	b[16] = 0                             // Checksum
+	binary.BigEndian.PutUint16(b[18:], 0) // Urgent pointer
+}
+
+func (b TCP) CalculateChecksum(initial uint16) uint16 {
+	return Checksum(b, initial)
+}
diff --git a/transport/internet/finalmask/rawpacket/windivert/assets/LICENSE.txt b/transport/internet/finalmask/rawpacket/windivert/assets/LICENSE.txt
new file mode 100644
index 000000000000..8489a8e773c3
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/windivert/assets/LICENSE.txt
@@ -0,0 +1,1191 @@
+WinDivert is dual-licensed under your choice of the GNU Lesser General Public
+License (LGPL) Version 3 or the GNU General Public License (GPL) Version 2.
+Copies of the LGPLv3, GPLv3 and GPLv2 are provided below.
+
+==============================================================================
+
+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+  A "Combined Work" is a work produced by combining or linking an
+Application with the Library.  The particular version of the Library
+with which the Combined Work was made is also called the "Linked
+Version".
+
+  The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+  The "Corresponding Application Code" for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+  2. Conveying Modified Versions.
+
+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+   a) under this License, provided that you make a good faith effort to
+   ensure that, in the event an Application does not supply the
+   function or data, the facility still operates, and performs
+   whatever part of its purpose remains meaningful, or
+
+   b) under the GNU GPL, with none of the additional permissions of
+   this License applicable to that copy.
+
+  3. Object Code Incorporating Material from Library Header Files.
+
+  The object code form of an Application may incorporate material from
+a header file that is part of the Library.  You may convey such object
+code under terms of your choice, provided that, if the incorporated
+material is not limited to numerical parameters, data structure
+layouts and accessors, or small macros, inline functions and templates
+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the object code with a copy of the GNU GPL and this license
+   document.
+
+  4. Combined Works.
+
+  You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+   a) Give prominent notice with each copy of the Combined Work that
+   the Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the Combined Work with a copy of the GNU GPL and this license
+   document.
+
+   c) For a Combined Work that displays copyright notices during
+   execution, include the copyright notice for the Library among
+   these notices, as well as a reference directing the user to the
+   copies of the GNU GPL and this license document.
+
+   d) Do one of the following:
+
+       0) Convey the Minimal Corresponding Source under the terms of this
+       License, and the Corresponding Application Code in a form
+       suitable for, and under terms that permit, the user to
+       recombine or relink the Application with a modified version of
+       the Linked Version to produce a modified Combined Work, in the
+       manner specified by section 6 of the GNU GPL for conveying
+       Corresponding Source.
+
+       1) Use a suitable shared library mechanism for linking with the
+       Library.  A suitable mechanism is one that (a) uses at run time
+       a copy of the Library already present on the user's computer
+       system, and (b) will operate properly with a modified version
+       of the Library that is interface-compatible with the Linked
+       Version.
+
+   e) Provide Installation Information, but only if you would otherwise
+   be required to provide such information under section 6 of the
+   GNU GPL, and only to the extent that such information is
+   necessary to install and execute a modified version of the
+   Combined Work produced by recombining or relinking the
+   Application with a modified version of the Linked Version. (If
+   you use option 4d0, the Installation Information must accompany
+   the Minimal Corresponding Source and Corresponding Application
+   Code. If you use option 4d1, you must provide the Installation
+   Information in the manner specified by section 6 of the GNU GPL
+   for conveying Corresponding Source.)
+
+  5. Combined Libraries.
+
+  You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+   a) Accompany the combined library with a copy of the same work based
+   on the Library, uncombined with any other library facilities,
+   conveyed under the terms of this License.
+
+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
+
+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.
+
+==============================================================================
+
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.  We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors.  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights.  Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received.  You must make sure that they, too, receive
+or can get the source code.  And you must show them these terms so they
+know their rights.
+
+  Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+  For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software.  For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+  Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so.  This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software.  The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable.  Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products.  If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+  Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary.  To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
+
+  0. Definitions.
+
+  "This License" refers to version 3 of the GNU General Public License.
+
+  "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+  "The Program" refers to any copyrightable work licensed under this
+License.  Each licensee is addressed as "you".  "Licensees" and
+"recipients" may be individuals or organizations.
+
+  To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy.  The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+  A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+  To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy.  Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+  To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies.  Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+  An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License.  If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+  1. Source Code.
+
+  The "source code" for a work means the preferred form of the work
+for making modifications to it.  "Object code" means any non-source
+form of a work.
+
+  A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+  The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form.  A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+  The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities.  However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work.  For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+  The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+  The Corresponding Source for a work in source code form is that
+same work.
+
+  2. Basic Permissions.
+
+  All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met.  This License explicitly affirms your unlimited
+permission to run the unmodified Program.  The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work.  This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+  You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force.  You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright.  Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+  Conveying under any other circumstances is permitted solely under
+the conditions stated below.  Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+  3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+  No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+  When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+  4. Conveying Verbatim Copies.
+
+  You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+  You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+  5. Conveying Modified Source Versions.
+
+  You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+    a) The work must carry prominent notices stating that you modified
+    it, and giving a relevant date.
+
+    b) The work must carry prominent notices stating that it is
+    released under this License and any conditions added under section
+    7.  This requirement modifies the requirement in section 4 to
+    "keep intact all notices".
+
+    c) You must license the entire work, as a whole, under this
+    License to anyone who comes into possession of a copy.  This
+    License will therefore apply, along with any applicable section 7
+    additional terms, to the whole of the work, and all its parts,
+    regardless of how they are packaged.  This License gives no
+    permission to license the work in any other way, but it does not
+    invalidate such permission if you have separately received it.
+
+    d) If the work has interactive user interfaces, each must display
+    Appropriate Legal Notices; however, if the Program has interactive
+    interfaces that do not display Appropriate Legal Notices, your
+    work need not make them do so.
+
+  A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+"aggregate" if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit.  Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+  6. Conveying Non-Source Forms.
+
+  You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:
+
+    a) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by the
+    Corresponding Source fixed on a durable physical medium
+    customarily used for software interchange.
+
+    b) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by a
+    written offer, valid for at least three years and valid for as
+    long as you offer spare parts or customer support for that product
+    model, to give anyone who possesses the object code either (1) a
+    copy of the Corresponding Source for all the software in the
+    product that is covered by this License, on a durable physical
+    medium customarily used for software interchange, for a price no
+    more than your reasonable cost of physically performing this
+    conveying of source, or (2) access to copy the
+    Corresponding Source from a network server at no charge.
+
+    c) Convey individual copies of the object code with a copy of the
+    written offer to provide the Corresponding Source.  This
+    alternative is allowed only occasionally and noncommercially, and
+    only if you received the object code with such an offer, in accord
+    with subsection 6b.
+
+    d) Convey the object code by offering access from a designated
+    place (gratis or for a charge), and offer equivalent access to the
+    Corresponding Source in the same way through the same place at no
+    further charge.  You need not require recipients to copy the
+    Corresponding Source along with the object code.  If the place to
+    copy the object code is a network server, the Corresponding Source
+    may be on a different server (operated by you or a third party)
+    that supports equivalent copying facilities, provided you maintain
+    clear directions next to the object code saying where to find the
+    Corresponding Source.  Regardless of what server hosts the
+    Corresponding Source, you remain obligated to ensure that it is
+    available for as long as needed to satisfy these requirements.
+
+    e) Convey the object code using peer-to-peer transmission, provided
+    you inform other peers where the object code and Corresponding
+    Source of the work are being offered to the general public at no
+    charge under subsection 6d.
+
+  A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+  A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling.  In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage.  For a particular
+product received by a particular user, "normally used" refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product.  A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.
+
+  "Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source.  The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.
+
+  If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information.  But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+  The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed.  Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.
+
+  Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+  7. Additional Terms.
+
+  "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law.  If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+  When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it.  (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.)  You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+  Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:
+
+    a) Disclaiming warranty or limiting liability differently from the
+    terms of sections 15 and 16 of this License; or
+
+    b) Requiring preservation of specified reasonable legal notices or
+    author attributions in that material or in the Appropriate Legal
+    Notices displayed by works containing it; or
+
+    c) Prohibiting misrepresentation of the origin of that material, or
+    requiring that modified versions of such material be marked in
+    reasonable ways as different from the original version; or
+
+    d) Limiting the use for publicity purposes of names of licensors or
+    authors of the material; or
+
+    e) Declining to grant rights under trademark law for use of some
+    trade names, trademarks, or service marks; or
+
+    f) Requiring indemnification of licensors and authors of that
+    material by anyone who conveys the material (or modified versions of
+    it) with contractual assumptions of liability to the recipient, for
+    any liability that these contractual assumptions directly impose on
+    those licensors and authors.
+
+  All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10.  If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term.  If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+  If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+  Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+  8. Termination.
+
+  You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+  However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+  Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+  Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+  9. Acceptance Not Required for Having Copies.
+
+  You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+  10. Automatic Licensing of Downstream Recipients.
+
+  Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.
+
+  An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+  You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+  11. Patents.
+
+  A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's "contributor version".
+
+  A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+  Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+  In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+  If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+  If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+  A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
+
+==============================================================================
+
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.
+
diff --git a/transport/internet/finalmask/rawpacket/windivert/assets/WinDivert32.sys b/transport/internet/finalmask/rawpacket/windivert/assets/WinDivert32.sys
new file mode 100644
index 000000000000..d06738cbb783
Binary files /dev/null and b/transport/internet/finalmask/rawpacket/windivert/assets/WinDivert32.sys differ
diff --git a/transport/internet/finalmask/rawpacket/windivert/assets/WinDivert64.sys b/transport/internet/finalmask/rawpacket/windivert/assets/WinDivert64.sys
new file mode 100644
index 000000000000..218ccaf423ef
Binary files /dev/null and b/transport/internet/finalmask/rawpacket/windivert/assets/WinDivert64.sys differ
diff --git a/transport/internet/finalmask/rawpacket/windivert/assets_386.go b/transport/internet/finalmask/rawpacket/windivert/assets_386.go
new file mode 100644
index 000000000000..0cbf35ed5cbf
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/windivert/assets_386.go
@@ -0,0 +1,14 @@
+//go:build windows && 386
+
+package windivert
+
+import _ "embed"
+
+//go:embed assets/WinDivert32.sys
+var sysBytes []byte
+
+func assetFiles() []assetFile {
+	return []assetFile{{"WinDivert32.sys", sysBytes}}
+}
+
+func driverSysName() string { return "WinDivert32.sys" }
diff --git a/transport/internet/finalmask/rawpacket/windivert/assets_amd64.go b/transport/internet/finalmask/rawpacket/windivert/assets_amd64.go
new file mode 100644
index 000000000000..2c9fb6c6ad19
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/windivert/assets_amd64.go
@@ -0,0 +1,14 @@
+//go:build windows && amd64
+
+package windivert
+
+import _ "embed"
+
+//go:embed assets/WinDivert64.sys
+var sysBytes []byte
+
+func assetFiles() []assetFile {
+	return []assetFile{{"WinDivert64.sys", sysBytes}}
+}
+
+func driverSysName() string { return "WinDivert64.sys" }
diff --git a/transport/internet/finalmask/rawpacket/windivert/assets_unsupported.go b/transport/internet/finalmask/rawpacket/windivert/assets_unsupported.go
new file mode 100644
index 000000000000..04698953fa6b
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/windivert/assets_unsupported.go
@@ -0,0 +1,7 @@
+//go:build windows && !amd64 && !386
+
+package windivert
+
+func assetFiles() []assetFile { return nil }
+
+func driverSysName() string { return "" }
diff --git a/transport/internet/finalmask/rawpacket/windivert/driver_windows.go b/transport/internet/finalmask/rawpacket/windivert/driver_windows.go
new file mode 100644
index 000000000000..50e94c578422
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/windivert/driver_windows.go
@@ -0,0 +1,211 @@
+//go:build windows
+
+package windivert
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strconv"
+	"sync"
+
+	"golang.org/x/sys/windows"
+)
+
+const (
+	driverServiceName = "WinDivert"
+	driverDeviceName  = `\\.\WinDivert`
+)
+
+var (
+	driverOnce sync.Once
+	driverErr  error
+	// driverDevName is ASCII-safe and must be available before ensureDriver
+	// so Open can try CreateFile first and only install on FILE_NOT_FOUND.
+	driverDevName, _ = windows.UTF16PtrFromString(driverDeviceName)
+)
+
+// Requires SeLoadDriverPrivilege (Administrator). Running the 386 build
+// under WOW64 on a 64-bit kernel is rejected — use the amd64 build.
+func ensureDriver() error {
+	driverOnce.Do(func() {
+		driverErr = installDriver()
+	})
+	return driverErr
+}
+
+func installDriver() error {
+	if runtime.GOARCH == "386" {
+		var isWow64 bool
+		err := windows.IsWow64Process(windows.CurrentProcess(), &isWow64)
+		if err == nil && isWow64 {
+			return errors.New("windivert: 386 build detected running under WOW64 on a 64-bit kernel; use the amd64 build")
+		}
+	}
+
+	dir, err := ensureExtracted()
+	if err != nil {
+		return err
+	}
+	sysPath := filepath.Join(dir, driverSysName())
+	sysPathW, err := windows.UTF16PtrFromString(sysPath)
+	if err != nil {
+		return fmt.Errorf("windivert: utf16 driver path: %w", err)
+	}
+
+	// Serialize driver install across concurrent processes.
+	mutexName, _ := windows.UTF16PtrFromString("WinDivertDriverInstallMutex")
+	mutex, err := windows.CreateMutex(nil, false, mutexName)
+	if err != nil {
+		return fmt.Errorf("windivert: create install mutex: %w", err)
+	}
+	defer windows.CloseHandle(mutex)
+	_, err = windows.WaitForSingleObject(mutex, windows.INFINITE)
+	if err != nil {
+		return fmt.Errorf("windivert: wait install mutex: %w", err)
+	}
+	defer windows.ReleaseMutex(mutex)
+
+	manager, err := windows.OpenSCManager(nil, nil, windows.SC_MANAGER_ALL_ACCESS)
+	if err != nil {
+		return fmt.Errorf("windivert: open SCM: %w", err)
+	}
+	defer windows.CloseServiceHandle(manager)
+
+	serviceNameW, _ := windows.UTF16PtrFromString(driverServiceName)
+	service, err := windows.OpenService(manager, serviceNameW, windows.SERVICE_ALL_ACCESS)
+	if err != nil {
+		service, err = windows.CreateService(
+			manager,
+			serviceNameW,
+			serviceNameW,
+			windows.SERVICE_ALL_ACCESS,
+			windows.SERVICE_KERNEL_DRIVER,
+			windows.SERVICE_DEMAND_START,
+			windows.SERVICE_ERROR_NORMAL,
+			sysPathW,
+			nil, nil, nil, nil, nil,
+		)
+		if err != nil {
+			if errors.Is(err, windows.ERROR_SERVICE_EXISTS) {
+				service, err = windows.OpenService(manager, serviceNameW, windows.SERVICE_ALL_ACCESS)
+			}
+			if err != nil {
+				return wrapDriverInstallError(err)
+			}
+		}
+	}
+	defer windows.CloseServiceHandle(service)
+
+	err = windows.StartService(service, 0, nil)
+	if err != nil && errors.Is(err, windows.ERROR_SERVICE_DISABLED) {
+		// A prior process called DeleteService on a still-running kernel
+		// driver: SCM marks the record for deletion and flips START_TYPE
+		// to DISABLED until the last handle closes. Re-enable so we can
+		// start it instead of waiting for a reboot.
+		err = windows.ChangeServiceConfig(
+			service,
+			windows.SERVICE_NO_CHANGE,
+			windows.SERVICE_DEMAND_START,
+			windows.SERVICE_NO_CHANGE,
+			nil, nil, nil, nil, nil, nil, nil,
+		)
+		if err != nil {
+			return fmt.Errorf("windivert: re-enable disabled service: %w", err)
+		}
+		err = windows.StartService(service, 0, nil)
+	}
+	if err == nil {
+		// Mark for deletion so the driver unregisters when the last handle
+		// closes or on next reboot. Matches the upstream DLL's behavior:
+		// only the process that actually started the service takes on the
+		// cleanup responsibility. If another process already started it,
+		// we leave DeleteService to them.
+		_ = windows.DeleteService(service)
+	} else if !errors.Is(err, windows.ERROR_SERVICE_ALREADY_RUNNING) {
+		return fmt.Errorf("windivert: start service: %w", err)
+	}
+	return nil
+}
+
+func wrapDriverInstallError(err error) error {
+	if errors.Is(err, windows.ERROR_ACCESS_DENIED) {
+		return fmt.Errorf("windivert: installing the kernel driver requires Administrator privileges: %w", err)
+	}
+	return fmt.Errorf("windivert: create service: %w", err)
+}
+
+type assetFile struct {
+	name string
+	data []byte
+}
+
+var (
+	extractOnce sync.Once
+	extractErr  error
+	extractDir  string
+)
+
+// The on-disk copy is protected by Windows Authenticode signature
+// enforcement, which rejects any tampered .sys at StartService time.
+func ensureExtracted() (string, error) {
+	extractOnce.Do(func() {
+		extractDir, extractErr = extractImpl()
+	})
+	return extractDir, extractErr
+}
+
+func extractImpl() (string, error) {
+	files := assetFiles()
+	if len(files) == 0 {
+		return "", fmt.Errorf("windivert: unsupported architecture %s", runtime.GOARCH)
+	}
+
+	base, err := os.UserCacheDir()
+	if err != nil {
+		return "", fmt.Errorf("windivert: locate user cache dir: %w", err)
+	}
+	dir := filepath.Join(base, "xray-core", "windivert", "v"+AssetVersion)
+	err = os.MkdirAll(dir, 0o755)
+	if err != nil {
+		return "", fmt.Errorf("windivert: mkdir %s: %w", dir, err)
+	}
+
+	for _, asset := range files {
+		err = ensureAsset(dir, asset)
+		if err != nil {
+			return "", err
+		}
+	}
+	return dir, nil
+}
+
+// Concurrent sing-box processes race on os.Rename (atomic on NTFS);
+// whichever wins creates the final file. Writers that lose the race
+// silently discard their temp copy.
+func ensureAsset(dir string, asset assetFile) error {
+	target := filepath.Join(dir, asset.name)
+	_, err := os.Stat(target)
+	if err == nil {
+		return nil
+	}
+	if !os.IsNotExist(err) {
+		return fmt.Errorf("windivert: stat %s: %w", asset.name, err)
+	}
+	tmp := target + ".tmp-" + strconv.Itoa(os.Getpid())
+	err = os.WriteFile(tmp, asset.data, 0o644)
+	if err != nil {
+		return fmt.Errorf("windivert: write %s: %w", asset.name, err)
+	}
+	err = os.Rename(tmp, target)
+	if err != nil {
+		os.Remove(tmp)
+		if _, statErr := os.Stat(target); statErr == nil {
+			return nil
+		}
+		return fmt.Errorf("windivert: rename %s: %w", asset.name, err)
+	}
+	return nil
+}
diff --git a/transport/internet/finalmask/rawpacket/windivert/filter.go b/transport/internet/finalmask/rawpacket/windivert/filter.go
new file mode 100644
index 000000000000..fbc58b9c0e08
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/windivert/filter.go
@@ -0,0 +1,199 @@
+package windivert
+
+import (
+	"encoding/binary"
+	"errors"
+	"net/netip"
+)
+
+// WINDIVERT_FILTER VM instruction layout (24 bytes, #pragma pack(1)):
+//
+//	word 0 (LE):  field:11 | test:5 | success:16
+//	word 1 (LE):  failure:16 | neg:1 | reserved:15
+//	words 2..5:   arg[4] (native-endian uint32 each)
+//
+// The driver walks this as a decision tree: evaluate the test at inst i;
+// on success jump to success; on failure jump to failure. Continuations
+// 0x7FFE and 0x7FFF are ACCEPT and REJECT terminals.
+const (
+	filterInstBytes = 24
+	filterMaxInsts  = 256
+
+	fieldZero        = 0
+	fieldOutbound    = 2
+	fieldIP          = 5
+	fieldIPv6        = 6
+	fieldTCP         = 8
+	fieldIPSrcAddr   = 21
+	fieldIPDstAddr   = 22
+	fieldIPv6SrcAddr = 28
+	fieldIPv6DstAddr = 29
+	fieldTCPSrcPort  = 38
+	fieldTCPDstPort  = 39
+
+	testEQ = 0
+
+	resultAccept uint16 = 0x7FFE
+	resultReject uint16 = 0x7FFF
+)
+
+// Filter flags passed to IOCTL_WINDIVERT_STARTUP alongside the compiled
+// filter. These tell the driver what *kinds* of packets the filter might
+// match, used as a kernel-side fast-reject.
+const (
+	filterFlagOutbound uint64 = 0x0020
+	filterFlagIP       uint64 = 0x0040
+	filterFlagIPv6     uint64 = 0x0080
+)
+
+type filterInst struct {
+	field   uint16 // 11 bits used
+	test    uint8  //  5 bits used
+	success uint16
+	failure uint16
+	neg     bool
+	arg     [4]uint32
+}
+
+// Filter is a typed specification of packets to capture. It replaces
+// WinDivert's filter string language.
+//
+// Zero value = "reject all" (match nothing), suitable for send-only handles.
+type Filter struct {
+	insts []filterInst
+	flags uint64 // filter flags for STARTUP ioctl
+}
+
+// reject returns a filter that matches no packet. The empty insts slice
+// is encoded as a single rejecting instruction by encode().
+func reject() *Filter {
+	return &Filter{}
+}
+
+// AcceptAll returns a filter that matches every network-layer packet.
+// Suitable for sniffing handles that filter in userspace. All filter
+// flags are set since the filter may match any packet class.
+func AcceptAll() *Filter {
+	f := &Filter{flags: filterFlagOutbound | filterFlagIP | filterFlagIPv6}
+	f.add(fieldZero, testEQ, argUint32(0))
+	return f
+}
+
+// OutboundTCP returns a filter matching outbound TCP packets on the given
+// 5-tuple. Both addresses must share an address family (IPv4 or IPv6).
+func OutboundTCP(src, dst netip.AddrPort) (*Filter, error) {
+	return tcpFilter(src, dst, true)
+}
+
+// BidirectionalTCP returns a filter matching TCP packets in either direction
+// on the given 5-tuple. Both addresses must share an address family.
+func BidirectionalTCP(src, dst netip.AddrPort) (*Filter, error) {
+	return tcpFilter(src, dst, false)
+}
+
+func tcpFilter(src, dst netip.AddrPort, outboundOnly bool) (*Filter, error) {
+	if !src.IsValid() || !dst.IsValid() {
+		return nil, errors.New("windivert: filter: invalid address port")
+	}
+	if src.Addr().Is4() != dst.Addr().Is4() {
+		return nil, errors.New("windivert: filter: mixed IPv4/IPv6")
+	}
+	f := &Filter{}
+	if outboundOnly {
+		f.flags = filterFlagOutbound
+		f.add(fieldOutbound, testEQ, argUint32(1))
+	}
+	if src.Addr().Is4() {
+		f.flags |= filterFlagIP
+		f.add(fieldIP, testEQ, argUint32(1))
+		f.add(fieldTCP, testEQ, argUint32(1))
+		f.add(fieldIPSrcAddr, testEQ, argIPv4(src.Addr()))
+		f.add(fieldIPDstAddr, testEQ, argIPv4(dst.Addr()))
+	} else {
+		f.flags |= filterFlagIPv6
+		f.add(fieldIPv6, testEQ, argUint32(1))
+		f.add(fieldTCP, testEQ, argUint32(1))
+		f.add(fieldIPv6SrcAddr, testEQ, argIPv6(src.Addr()))
+		f.add(fieldIPv6DstAddr, testEQ, argIPv6(dst.Addr()))
+	}
+	f.add(fieldTCPSrcPort, testEQ, argUint32(uint32(src.Port())))
+	f.add(fieldTCPDstPort, testEQ, argUint32(uint32(dst.Port())))
+	return f, nil
+}
+
+func (f *Filter) add(field uint16, test uint8, arg [4]uint32) {
+	f.insts = append(f.insts, filterInst{field: field, test: test, arg: arg})
+}
+
+func argUint32(v uint32) [4]uint32 { return [4]uint32{v, 0, 0, 0} }
+
+// argIPv4 encodes an IPv4 address for IP_SRCADDR/IP_DSTADDR. The driver
+// compares against an IPv4-mapped-IPv6 form: {host_order_u32, 0x0000FFFF,
+// 0, 0} (see sys/windivert.c windivert_get_ipv4_addr and the IPv4_SRCADDR
+// val-word construction). Omitting the 0x0000FFFF marker causes the EQ
+// test to fail for every packet.
+func argIPv4(addr netip.Addr) [4]uint32 {
+	b := addr.As4()
+	return [4]uint32{binary.BigEndian.Uint32(b[:]), 0x0000FFFF, 0, 0}
+}
+
+// argIPv6 encodes an IPv6 address for IPV6_SRCADDR/IPV6_DSTADDR. The
+// driver stores the address as four host-order uint32s in REVERSED word
+// order: val[0]=low (bytes 12..15), val[3]=high (bytes 0..3). See
+// sys/windivert.c windivert_outbound_network_v6_classify val-word
+// construction.
+func argIPv6(addr netip.Addr) [4]uint32 {
+	b := addr.As16()
+	return [4]uint32{
+		binary.BigEndian.Uint32(b[12:16]),
+		binary.BigEndian.Uint32(b[8:12]),
+		binary.BigEndian.Uint32(b[4:8]),
+		binary.BigEndian.Uint32(b[0:4]),
+	}
+}
+
+// encode serializes the Filter to the on-wire WINDIVERT_FILTER[] format
+// plus the filter_flags for STARTUP ioctl.
+func (f *Filter) encode() ([]byte, uint64, error) {
+	if len(f.insts) == 0 {
+		// "Reject all" — one instruction, ZERO == 0 is always true, but we
+		// invert by setting both success and failure to REJECT.
+		return encodeInst(filterInst{
+			field:   fieldZero,
+			test:    testEQ,
+			success: resultReject,
+			failure: resultReject,
+		}), 0, nil
+	}
+	if len(f.insts) > filterMaxInsts-1 {
+		return nil, 0, errors.New("windivert: filter too long")
+	}
+	buf := make([]byte, 0, filterInstBytes*len(f.insts))
+	for i, inst := range f.insts {
+		if i == len(f.insts)-1 {
+			inst.success = resultAccept
+		} else {
+			inst.success = uint16(i + 1)
+		}
+		inst.failure = resultReject
+		buf = append(buf, encodeInst(inst)...)
+	}
+	return buf, f.flags, nil
+}
+
+func encodeInst(inst filterInst) []byte {
+	out := make([]byte, filterInstBytes)
+	word0 := uint32(inst.field&0x7FF) | uint32(inst.test&0x1F)<<11 |
+		uint32(inst.success)<<16
+	word1 := uint32(inst.failure)
+	if inst.neg {
+		word1 |= 1 << 16
+	}
+	binary.LittleEndian.PutUint32(out[0:4], word0)
+	binary.LittleEndian.PutUint32(out[4:8], word1)
+	binary.LittleEndian.PutUint32(out[8:12], inst.arg[0])
+	binary.LittleEndian.PutUint32(out[12:16], inst.arg[1])
+	binary.LittleEndian.PutUint32(out[16:20], inst.arg[2])
+	binary.LittleEndian.PutUint32(out[20:24], inst.arg[3])
+	return out
+}
diff --git a/transport/internet/finalmask/rawpacket/windivert/handle_windows.go b/transport/internet/finalmask/rawpacket/windivert/handle_windows.go
new file mode 100644
index 000000000000..c48e6214c11b
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/windivert/handle_windows.go
@@ -0,0 +1,323 @@
+//go:build windows
+
+package windivert
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"runtime"
+	"sync"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+// Handle owns a WinDivert kernel device handle plus a private event for
+// overlapped I/O. Methods on *Handle are not safe for concurrent use
+// across goroutines (there is a single shared event per Handle).
+//
+// addr is a per-Handle Address buffer the IOCTL struct embeds a pointer
+// to. It lives on the heap (as a field of a heap-allocated Handle) so
+// the pointer value stored as bytes in the ioctl buffer remains valid
+// across stack growth between buildIoctl* and the DeviceIoControl
+// syscall — stack-local Address values are not safe for this pattern
+// because Go's escape analysis does not see the pointer through the
+// unsafe.Pointer → uintptr → bytes conversion.
+type Handle struct {
+	device   windows.Handle
+	event    windows.Handle
+	closing  sync.Once
+	closeErr error
+	addr     Address
+}
+
+// Filter may be nil for "reject all", suitable for send-only handles.
+// Requires Administrator on first call per process (installs the kernel
+// driver via SCM); subsequent calls reuse the running driver.
+func Open(filter *Filter, layer Layer, priority int16, flags Flag) (*Handle, error) {
+	err := validateOpenArgs(layer, priority, flags)
+	if err != nil {
+		return nil, err
+	}
+	if filter == nil {
+		filter = reject()
+	}
+	filterBin, filterFlags, err := filter.encode()
+	if err != nil {
+		return nil, err
+	}
+	device, err := openDevice()
+	if err != nil {
+		if !errors.Is(err, windows.ERROR_FILE_NOT_FOUND) &&
+			!errors.Is(err, windows.ERROR_PATH_NOT_FOUND) {
+			if errors.Is(err, windows.ERROR_ACCESS_DENIED) {
+				return nil, fmt.Errorf("windivert: open device (administrator required): %w", err)
+			}
+			return nil, fmt.Errorf("windivert: open device: %w", err)
+		}
+		// Device node missing: kernel driver not loaded. Install + retry.
+		// Matches WinDivertOpen's lazy-install path; avoids racing StartService
+		// against a still-loaded driver whose SCM record is marked for deletion.
+		err = ensureDriver()
+		if err != nil {
+			return nil, err
+		}
+		device, err = openDevice()
+		if err != nil {
+			if errors.Is(err, windows.ERROR_ACCESS_DENIED) {
+				return nil, fmt.Errorf("windivert: open device (administrator required): %w", err)
+			}
+			return nil, fmt.Errorf("windivert: open device: %w", err)
+		}
+	}
+	event, err := windows.CreateEvent(nil, 1, 0, nil) // manual reset, unsignaled
+	if err != nil {
+		windows.CloseHandle(device)
+		return nil, fmt.Errorf("windivert: create event: %w", err)
+	}
+	h := &Handle{device: device, event: event}
+
+	err = h.initialize(layer, priority, flags)
+	if err != nil {
+		h.Close()
+		return nil, err
+	}
+	err = h.startup(filterBin, filterFlags)
+	if err != nil {
+		h.Close()
+		return nil, err
+	}
+	return h, nil
+}
+
+func openDevice() (windows.Handle, error) {
+	return windows.CreateFile(
+		driverDevName,
+		windows.GENERIC_READ|windows.GENERIC_WRITE,
+		0, nil,
+		windows.OPEN_EXISTING,
+		windows.FILE_ATTRIBUTE_NORMAL|windows.FILE_FLAG_OVERLAPPED,
+		0,
+	)
+}
+
+func validateOpenArgs(layer Layer, priority int16, flags Flag) error {
+	if layer != LayerNetwork {
+		return fmt.Errorf("windivert: invalid layer %d", uint32(layer))
+	}
+	if priority < PriorityLowest || priority > PriorityHighest {
+		return errors.New("windivert: priority out of range")
+	}
+	const supportedFlags = FlagSniff | FlagSendOnly
+	if flags&^supportedFlags != 0 {
+		return errors.New("windivert: unknown flag bits")
+	}
+	if flags&FlagSniff != 0 && flags&FlagSendOnly != 0 {
+		return errors.New("windivert: FlagSniff and FlagSendOnly are mutually exclusive")
+	}
+	return nil
+}
+
+func (h *Handle) initialize(layer Layer, priority int16, flags Flag) error {
+	in := buildIoctlInitialize(layer, priority, flags)
+	// WINDIVERT_VERSION is a 64-byte packed struct; only the first 20
+	// bytes (magic, major, minor, bits) carry data, the rest is reserved.
+	var outBuf [versionStructSize]byte
+	binary.LittleEndian.PutUint64(outBuf[0:8], magicDLL)
+	binary.LittleEndian.PutUint32(outBuf[8:12], versionMajor)
+	binary.LittleEndian.PutUint32(outBuf[12:16], versionMinor)
+	binary.LittleEndian.PutUint32(outBuf[16:20], uint32(unsafe.Sizeof(uintptr(0))*8))
+	_, err := doIoctl(h.device, ioctlInitialize, in[:], outBuf[:], h.event)
+	if err != nil {
+		return fmt.Errorf("windivert: initialize ioctl: %w", err)
+	}
+	gotMagic := binary.LittleEndian.Uint64(outBuf[0:8])
+	if gotMagic != magicSYS {
+		return fmt.Errorf("windivert: driver magic mismatch (got %d)", gotMagic)
+	}
+	gotMajor := binary.LittleEndian.Uint32(outBuf[8:12])
+	if gotMajor < versionMajor {
+		gotMinor := binary.LittleEndian.Uint32(outBuf[12:16])
+		return fmt.Errorf("windivert: driver version too old: %d.%d", gotMajor, gotMinor)
+	}
+	return nil
+}
+
+func (h *Handle) startup(filterBin []byte, filterFlags uint64) error {
+	in := buildIoctlStartup(filterFlags)
+	_, err := doIoctl(h.device, ioctlStartup, in[:], filterBin, h.event)
+	if err != nil {
+		return fmt.Errorf("windivert: startup ioctl: %w", err)
+	}
+	return nil
+}
+
+// If the handle is closed mid-Recv the error wraps ERROR_OPERATION_ABORTED.
+func (h *Handle) Recv(buf []byte) (int, Address, error) {
+	if len(buf) == 0 {
+		return 0, Address{}, errors.New("windivert: recv: zero-length buffer")
+	}
+	h.addr = Address{}
+	in := buildIoctlRecv(&h.addr)
+	n, err := doIoctl(h.device, ioctlRecv, in[:], buf, h.event)
+	runtime.KeepAlive(h)
+	if err != nil {
+		return 0, Address{}, err
+	}
+	return int(n), h.addr, nil
+}
+
+// The address's Outbound flag controls whether the packet is sent toward
+// the wire (outbound=true) or delivered up the stack (outbound=false).
+// IfIdx and SubIfIdx can stay zero — the driver uses the routing table
+// when IfIdx=0.
+func (h *Handle) Send(packet []byte, addr *Address) (int, error) {
+	if len(packet) == 0 {
+		return 0, errors.New("windivert: send: empty packet")
+	}
+	if addr == nil {
+		return 0, errors.New("windivert: send: nil address")
+	}
+	h.addr = *addr
+	in := buildIoctlSend(&h.addr)
+	n, err := doIoctl(h.device, ioctlSend, in[:], packet, h.event)
+	runtime.KeepAlive(h)
+	if err != nil {
+		return 0, err
+	}
+	return int(n), nil
+}
+
+// Idempotent. Aborts any in-flight I/O on the handle.
+func (h *Handle) Close() error {
+	h.closing.Do(func() {
+		var errs []error
+		if h.device != 0 {
+			err := windows.CloseHandle(h.device)
+			if err != nil {
+				errs = append(errs, err)
+			}
+			h.device = 0
+		}
+		if h.event != 0 {
+			err := windows.CloseHandle(h.event)
+			if err != nil {
+				errs = append(errs, err)
+			}
+			h.event = 0
+		}
+		h.closeErr = errors.Join(errs...)
+	})
+	return h.closeErr
+}
+
+// IOCTL codes from windivert_device.h. CTL_CODE macro layout:
+//
+//	(DeviceType << 16) | (Access << 14) | (Function << 2) | Method
+const (
+	fileDeviceNetwork uint32 = 0x12
+	accessReadWrite   uint32 = 3 // FILE_READ_DATA | FILE_WRITE_DATA
+	accessRead        uint32 = 1
+
+	methodInDirect  uint32 = 1
+	methodOutDirect uint32 = 2
+)
+
+func ctlCode(deviceType, access, function, method uint32) uint32 {
+	return (deviceType << 16) | (access << 14) | (function << 2) | method
+}
+
+var (
+	ioctlInitialize = ctlCode(fileDeviceNetwork, accessReadWrite, 0x921, methodOutDirect)
+	ioctlStartup    = ctlCode(fileDeviceNetwork, accessReadWrite, 0x922, methodInDirect)
+	ioctlRecv       = ctlCode(fileDeviceNetwork, accessRead, 0x923, methodOutDirect)
+	ioctlSend       = ctlCode(fileDeviceNetwork, accessReadWrite, 0x924, methodInDirect)
+)
+
+// Magic numbers exchanged during INITIALIZE. DLL sends magicDLL in the
+// version struct; driver returns magicSYS on success.
+const (
+	magicDLL uint64 = 0x4C4C447669645724 // "$WdivDLL" in LE bytes
+	magicSYS uint64 = 0x5359537669645723 // "#WdivSYS" in LE bytes
+)
+
+const (
+	versionMajor uint32 = 2
+	versionMinor uint32 = 2
+)
+
+// Size of the WINDIVERT_IOCTL union on wire (packed).
+const ioctlSize = 16
+
+// Size of WINDIVERT_VERSION on wire (packed). Only the first 20 bytes
+// carry data; the rest is reserved zero padding.
+const versionStructSize = 64
+
+// doIoctl performs a single synchronous (blocking) overlapped
+// DeviceIoControl. The handle is opened with FILE_FLAG_OVERLAPPED so
+// DeviceIoControl returns ERROR_IO_PENDING; we then wait for completion
+// via GetOverlappedResult. Event is passed in so callers can reuse it
+// across calls on the same handle (avoids per-call CreateEvent).
+func doIoctl(handle windows.Handle, code uint32, in []byte, out []byte, event windows.Handle) (uint32, error) {
+	var overlapped windows.Overlapped
+	overlapped.HEvent = event
+	_ = windows.ResetEvent(event)
+
+	var inPtr *byte
+	var inLen uint32
+	if len(in) > 0 {
+		inPtr = &in[0]
+		inLen = uint32(len(in))
+	}
+	var outPtr *byte
+	var outLen uint32
+	if len(out) > 0 {
+		outPtr = &out[0]
+		outLen = uint32(len(out))
+	}
+	var returned uint32
+	err := windows.DeviceIoControl(handle, code, inPtr, inLen, outPtr, outLen, &returned, &overlapped)
+	if err != nil && !errors.Is(err, windows.ERROR_IO_PENDING) {
+		return 0, err
+	}
+	err = windows.GetOverlappedResult(handle, &overlapped, &returned, true)
+	if err != nil {
+		return 0, err
+	}
+	return returned, nil
+}
+
+func buildIoctlInitialize(layer Layer, priority int16, flags Flag) [ioctlSize]byte {
+	var buf [ioctlSize]byte
+	binary.LittleEndian.PutUint32(buf[0:4], uint32(layer))
+	// The driver expects priority + WINDIVERT_PRIORITY_HIGHEST (30000) so
+	// the low range maps to non-negative integers.
+	binary.LittleEndian.PutUint32(buf[4:8], uint32(int32(priority)+int32(PriorityHighest)))
+	binary.LittleEndian.PutUint64(buf[8:16], uint64(flags))
+	return buf
+}
+
+func buildIoctlStartup(filterFlags uint64) [ioctlSize]byte {
+	var buf [ioctlSize]byte
+	binary.LittleEndian.PutUint64(buf[0:8], filterFlags)
+	return buf
+}
+
+// buildIoctlRecv packs a user-space pointer to a WINDIVERT_ADDRESS into
+// the ioctl struct. The driver dereferences it to write the address for
+// the received packet. Caller must keep the Address alive via
+// runtime.KeepAlive.
+func buildIoctlRecv(addr *Address) [ioctlSize]byte {
+	var buf [ioctlSize]byte
+	binary.LittleEndian.PutUint64(buf[0:8], uint64(uintptr(unsafe.Pointer(addr))))
+	binary.LittleEndian.PutUint64(buf[8:16], 0)
+	return buf
+}
+
+func buildIoctlSend(addr *Address) [ioctlSize]byte {
+	var buf [ioctlSize]byte
+	binary.LittleEndian.PutUint64(buf[0:8], uint64(uintptr(unsafe.Pointer(addr))))
+	binary.LittleEndian.PutUint64(buf[8:16], uint64(unsafe.Sizeof(Address{})))
+	return buf
+}
diff --git a/transport/internet/finalmask/rawpacket/windivert/windivert.go b/transport/internet/finalmask/rawpacket/windivert/windivert.go
new file mode 100644
index 000000000000..9d309886cbe3
--- /dev/null
+++ b/transport/internet/finalmask/rawpacket/windivert/windivert.go
@@ -0,0 +1,78 @@
+// Package windivert provides a pure-Go binding to the WinDivert kernel
+// driver on Windows (amd64 and 386). User-mode WinDivert calls are
+// reimplemented in Go; only the signed kernel driver is embedded as an
+// asset, since SCM-installed drivers must live on disk and their
+// Authenticode signature forbids modification.
+//
+// Administrator is required for the first Open in a process so SCM can
+// load the driver. Upstream: https://github.com/basil00/WinDivert v2.2.2,
+// redistributed under its LGPL v3 option; see assets/LICENSE.txt.
+package windivert
+
+import "unsafe"
+
+const AssetVersion = "2.2.2"
+
+// MTUMax is WINDIVERT_MTU_MAX from windivert.h (40 + 0xFFFF). Suitable as
+// a single-packet receive buffer size.
+const MTUMax = 40 + 0xFFFF
+
+type Layer uint32
+
+const LayerNetwork Layer = 0
+
+type Flag uint64
+
+const (
+	// FlagSniff opens a passive observer: the driver copies matching packets
+	// to userspace without removing them from the network stack. Send is not
+	// required (and not allowed) on a sniffing handle.
+	FlagSniff Flag = 0x0001
+	// FlagSendOnly opens a write-only injection handle; Recv is not allowed.
+	FlagSendOnly Flag = 0x0008
+)
+
+const (
+	PriorityHighest int16 = 30000
+	PriorityLowest  int16 = -30000
+)
+
+// Address mirrors WINDIVERT_ADDRESS from windivert.h (80 bytes,
+// little-endian on both amd64 and 386):
+//
+//	 0: INT64  Timestamp
+//	 8: UINT32 bitfield: Layer:8 | Event:8 | flags | Reserved1:8
+//	12: UINT32 Reserved2
+//	16: 64 bytes union (WINDIVERT_DATA_NETWORK / FLOW / SOCKET / REFLECT)
+type Address struct {
+	Timestamp int64
+	bits      uint32
+	Reserved2 uint32
+	union     [64]byte
+}
+
+var _ [80]byte = [unsafe.Sizeof(Address{})]byte{}
+
+// Bit positions inside the Address's packed flags word.
+const (
+	addrBitIPv6        = 20
+	addrBitIPChecksum  = 21
+	addrBitTCPChecksum = 22
+)
+
+func getFlagBit(bits uint32, pos uint) bool { return bits&(1<<pos) != 0 }
+func setFlagBit(bits uint32, pos uint, v bool) uint32 {
+	if v {
+		return bits | (1 << pos)
+	}
+	return bits &^ (1 << pos)
+}
+
+func (a *Address) IPv6() bool { return getFlagBit(a.bits, addrBitIPv6) }
+func (a *Address) SetIPChecksum(v bool) {
+	a.bits = setFlagBit(a.bits, addrBitIPChecksum, v)
+}
+
+func (a *Address) SetTCPChecksum(v bool) {
+	a.bits = setFlagBit(a.bits, addrBitTCPChecksum, v)
+}
diff --git a/transport/internet/grpc/dial.go b/transport/internet/grpc/dial.go
index a54d7c02f877..1aa1518c6494 100644
--- a/transport/internet/grpc/dial.go
+++ b/transport/internet/grpc/dial.go
@@ -137,6 +137,15 @@ func getGrpcClient(ctx context.Context, dest net.Destination, streamSettings *in
 
 				if tlsConfig != nil {
 					config := tlsConfig.GetTLSConfig(tls.WithDestination(dest))
+					if config.ServerName == "" && address.Family().IsDomain() {
+						config.ServerName = address.Domain()
+					}
+					if spoofConn, err := tls.WrapWithSpoof(c, tlsConfig.Spoof, tlsConfig.SpoofMethod, tlsConfig.SpoofCount, config.ServerName); err != nil {
+						c.Close()
+						return nil, err
+					} else {
+						c = spoofConn
+					}
 					if fingerprint := tls.GetFingerprint(tlsConfig.Fingerprint); fingerprint != nil {
 						return tls.UClient(c, config, fingerprint), nil
 					} else { // Fallback to normal gRPC TLS
diff --git a/transport/internet/httpupgrade/dialer.go b/transport/internet/httpupgrade/dialer.go
index 571797f6172d..bb9df1c912fb 100644
--- a/transport/internet/httpupgrade/dialer.go
+++ b/transport/internet/httpupgrade/dialer.go
@@ -66,6 +66,12 @@ func dialhttpUpgrade(ctx context.Context, dest net.Destination, streamSettings *
 	tConfig := tls.ConfigFromStreamSettings(streamSettings)
 	if tConfig != nil {
 		tlsConfig := tConfig.GetTLSConfig(tls.WithDestination(dest), tls.WithNextProto("http/1.1"))
+		if spoofConn, err := tls.WrapWithSpoof(pconn, tConfig.Spoof, tConfig.SpoofMethod, tConfig.SpoofCount, tlsConfig.ServerName); err != nil {
+			pconn.Close()
+			return nil, err
+		} else {
+			pconn = spoofConn
+		}
 		if fingerprint := tls.GetFingerprint(tConfig.Fingerprint); fingerprint != nil {
 			conn = tls.UClient(pconn, tlsConfig, fingerprint)
 			if err := conn.(*tls.UConn).WebsocketHandshakeContext(ctx); err != nil {
diff --git a/transport/internet/kcp/dialer.go b/transport/internet/kcp/dialer.go
index 175998ec7dd3..e3ff0bdc9a19 100644
--- a/transport/internet/kcp/dialer.go
+++ b/transport/internet/kcp/dialer.go
@@ -97,7 +97,14 @@ func DialKCP(ctx context.Context, dest net.Destination, streamSettings *internet
 	var iConn stat.Connection = session
 
 	if config := tls.ConfigFromStreamSettings(streamSettings); config != nil {
-		iConn = tls.Client(iConn, config.GetTLSConfig(tls.WithDestination(dest)))
+		tlsConfig := config.GetTLSConfig(tls.WithDestination(dest))
+		if spoofConn, err := tls.WrapWithSpoof(iConn, config.Spoof, config.SpoofMethod, config.SpoofCount, tlsConfig.ServerName); err != nil {
+			iConn.Close()
+			return nil, err
+		} else {
+			iConn = spoofConn.(stat.Connection)
+		}
+		iConn = tls.Client(iConn, tlsConfig)
 	}
 
 	return iConn, nil
diff --git a/transport/internet/splithttp/dialer.go b/transport/internet/splithttp/dialer.go
index 817d935528c9..8d4c77f1d0a1 100644
--- a/transport/internet/splithttp/dialer.go
+++ b/transport/internet/splithttp/dialer.go
@@ -137,6 +137,12 @@ func createHTTPClient(dest net.Destination, streamSettings *internet.MemoryStrea
 		}
 
 		if gotlsConfig != nil {
+			if spoofConn, err := tls.WrapWithSpoof(conn, tlsConfig.Spoof, tlsConfig.SpoofMethod, tlsConfig.SpoofCount, gotlsConfig.ServerName); err != nil {
+				conn.Close()
+				return nil, err
+			} else {
+				conn = spoofConn
+			}
 			if fingerprint := tls.GetFingerprint(tlsConfig.Fingerprint); fingerprint != nil {
 				conn = tls.UClient(conn, gotlsConfig, fingerprint)
 				if err := conn.(*tls.UConn).HandshakeContext(ctxInner); err != nil {
diff --git a/transport/internet/tcp/dialer.go b/transport/internet/tcp/dialer.go
index 92fa7557f13a..e226a5657cb3 100644
--- a/transport/internet/tcp/dialer.go
+++ b/transport/internet/tcp/dialer.go
@@ -74,6 +74,11 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 			}
 		}
 		if fingerprint := tls.GetFingerprint(config.Fingerprint); fingerprint != nil {
+			if spoofConn, err := tls.WrapWithSpoof(conn, config.Spoof, config.SpoofMethod, config.SpoofCount, tlsConfig.ServerName); err != nil {
+				return nil, err
+			} else {
+				conn = spoofConn
+			}
 			conn = tls.UClient(conn, tlsConfig, fingerprint)
 			if len(tlsConfig.NextProtos) == 1 && tlsConfig.NextProtos[0] == "http/1.1" { // allow manually specify
 				err = conn.(*tls.UConn).WebsocketHandshakeContext(ctx)
@@ -81,6 +86,11 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 				err = conn.(*tls.UConn).HandshakeContext(ctx)
 			}
 		} else {
+			if spoofConn, err := tls.WrapWithSpoof(conn, config.Spoof, config.SpoofMethod, config.SpoofCount, tlsConfig.ServerName); err != nil {
+				return nil, err
+			} else {
+				conn = spoofConn
+			}
 			conn = tls.Client(conn, tlsConfig)
 			err = conn.(*tls.Conn).HandshakeContext(ctx)
 		}
diff --git a/transport/internet/tls/config.pb.go b/transport/internet/tls/config.pb.go
index b622d5a61489..f3b08acd8788 100644
--- a/transport/internet/tls/config.pb.go
+++ b/transport/internet/tls/config.pb.go
@@ -1,7 +1,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
 // 	protoc-gen-go v1.36.11
-// 	protoc        v6.33.5
+// 	protoc        v7.35.1
 // source: transport/internet/tls/config.proto
 
 package tls
@@ -206,8 +206,17 @@ type Config struct {
 	EchConfigList        string                 `protobuf:"bytes,19,opt,name=ech_config_list,json=echConfigList,proto3" json:"ech_config_list,omitempty"`
 	EchSocketSettings    *internet.SocketConfig `protobuf:"bytes,21,opt,name=ech_socket_settings,json=echSocketSettings,proto3" json:"ech_socket_settings,omitempty"`
 	PinnedPeerCertSha256 [][]byte               `protobuf:"bytes,22,rep,name=pinned_peer_cert_sha256,json=pinnedPeerCertSha256,proto3" json:"pinned_peer_cert_sha256,omitempty"`
-	unknownFields        protoimpl.UnknownFields
-	sizeCache            protoimpl.SizeCache
+	// SNI to forge in the spoofed ClientHello sent via raw sockets before
+	// the real TLS handshake (sing-box style TLS spoofing).
+	Spoof string `protobuf:"bytes,23,opt,name=spoof,proto3" json:"spoof,omitempty"`
+	// How the spoofed ClientHello is corrupted to evade DPI: "wrong-sequence"
+	// (default), "wrong-checksum", "wrong-ack", "wrong-md5" or
+	// "wrong-timestamp".
+	SpoofMethod string `protobuf:"bytes,24,opt,name=spoof_method,json=spoofMethod,proto3" json:"spoof_method,omitempty"`
+	// Number of times to inject the fake ClientHello (0 or 1 = single-shot).
+	SpoofCount    int32 `protobuf:"varint,25,opt,name=spoof_count,json=spoofCount,proto3" json:"spoof_count,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
 }
 
 func (x *Config) Reset() {
@@ -359,6 +368,27 @@ func (x *Config) GetPinnedPeerCertSha256() [][]byte {
 	return nil
 }
 
+func (x *Config) GetSpoof() string {
+	if x != nil {
+		return x.Spoof
+	}
+	return ""
+}
+
+func (x *Config) GetSpoofMethod() string {
+	if x != nil {
+		return x.SpoofMethod
+	}
+	return ""
+}
+
+func (x *Config) GetSpoofCount() int32 {
+	if x != nil {
+		return x.SpoofCount
+	}
+	return 0
+}
+
 var File_transport_internet_tls_config_proto protoreflect.FileDescriptor
 
 const file_transport_internet_tls_config_proto_rawDesc = "" +
@@ -377,7 +407,7 @@ const file_transport_internet_tls_config_proto_rawDesc = "" +
 	"\x05Usage\x12\x10\n" +
 	"\fENCIPHERMENT\x10\x00\x12\x14\n" +
 	"\x10AUTHORITY_VERIFY\x10\x01\x12\x13\n" +
-	"\x0fAUTHORITY_ISSUE\x10\x02\"\xa6\x06\n" +
+	"\x0fAUTHORITY_ISSUE\x10\x02\"\x80\a\n" +
 	"\x06Config\x12J\n" +
 	"\vcertificate\x18\x02 \x03(\v2(.xray.transport.internet.tls.CertificateR\vcertificate\x12\x1f\n" +
 	"\vserver_name\x18\x03 \x01(\tR\n" +
@@ -398,7 +428,11 @@ const file_transport_internet_tls_config_proto_rawDesc = "" +
 	"\x0fech_server_keys\x18\x12 \x01(\fR\rechServerKeys\x12&\n" +
 	"\x0fech_config_list\x18\x13 \x01(\tR\rechConfigList\x12U\n" +
 	"\x13ech_socket_settings\x18\x15 \x01(\v2%.xray.transport.internet.SocketConfigR\x11echSocketSettings\x125\n" +
-	"\x17pinned_peer_cert_sha256\x18\x16 \x03(\fR\x14pinnedPeerCertSha256Bs\n" +
+	"\x17pinned_peer_cert_sha256\x18\x16 \x03(\fR\x14pinnedPeerCertSha256\x12\x14\n" +
+	"\x05spoof\x18\x17 \x01(\tR\x05spoof\x12!\n" +
+	"\fspoof_method\x18\x18 \x01(\tR\vspoofMethod\x12\x1f\n" +
+	"\vspoof_count\x18\x19 \x01(\x05R\n" +
+	"spoofCountBs\n" +
 	"\x1fcom.xray.transport.internet.tlsP\x01Z0github.com/xtls/xray-core/transport/internet/tls\xaa\x02\x1bXray.Transport.Internet.Tlsb\x06proto3"
 
 var (
diff --git a/transport/internet/tls/config.proto b/transport/internet/tls/config.proto
index a05cc049427d..88c1773864dd 100644
--- a/transport/internet/tls/config.proto
+++ b/transport/internet/tls/config.proto
@@ -86,4 +86,16 @@ message Config {
   SocketConfig ech_socket_settings = 21;
 
   repeated bytes pinned_peer_cert_sha256 = 22;
+
+  // SNI to forge in the spoofed ClientHello sent via raw sockets before
+  // the real TLS handshake (sing-box style TLS spoofing).
+  string spoof = 23;
+
+  // How the spoofed ClientHello is corrupted to evade DPI: "wrong-sequence"
+  // (default), "wrong-checksum", "wrong-ack", "wrong-md5" or
+  // "wrong-timestamp".
+  string spoof_method = 24;
+
+  // Number of times to inject the fake ClientHello (0 or 1 = single-shot).
+  int32 spoof_count = 25;
 }
diff --git a/transport/internet/tls/tls.go b/transport/internet/tls/tls.go
index df5d1cbd7cf0..69b2cf558877 100644
--- a/transport/internet/tls/tls.go
+++ b/transport/internet/tls/tls.go
@@ -5,13 +5,17 @@ import (
 	"crypto/rand"
 	"crypto/tls"
 	"math/big"
+	gonet "net"
 	"slices"
+	"strings"
 	"time"
 
 	utls "github.com/refraction-networking/utls"
 	"github.com/xtls/xray-core/common/buf"
+	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/common/utils"
+	"github.com/xtls/xray-core/transport/internet/tls/tlsspoof"
 )
 
 type Interface interface {
@@ -66,6 +70,35 @@ func Client(c net.Conn, config *tls.Config) net.Conn {
 	return &Conn{Conn: tlsConn}
 }
 
+// WrapWithSpoof wraps a connection with TLS spoofing if the config has
+// spoof settings. The spoofed ClientHello is injected via raw sockets
+// before the real TLS handshake, causing DPI middleboxes to see the
+// forged SNI while the actual connection proceeds normally.
+// spoofCount controls how many Write() calls trigger injection (0 = single-shot).
+func WrapWithSpoof(c net.Conn, spoofSNI string, spoofMethodStr string, spoofCount int32, serverName string) (net.Conn, error) {
+	spoofSNI, method, err := tlsspoof.ParseOptions(spoofSNI, spoofMethodStr)
+	if err != nil {
+		return nil, errors.New("tls_spoof: invalid options").Base(err)
+	}
+	if spoofSNI == "" {
+		return c, nil
+	}
+	if serverName == "" {
+		return nil, errors.New("tls_spoof: requires a TLS server name (SNI)")
+	}
+	if gonet.ParseIP(serverName) != nil {
+		return nil, errors.New("tls_spoof: cannot spoof when server name is an IP literal")
+	}
+	if strings.EqualFold(spoofSNI, serverName) {
+		return nil, errors.New("tls_spoof: spoof must differ from server_name")
+	}
+	wrapped, err := tlsspoof.NewConn(c, method, spoofSNI, int(spoofCount))
+	if err != nil {
+		return nil, errors.New("tls_spoof: failed to create spoof conn").Base(err)
+	}
+	return wrapped, nil
+}
+
 // Server initiates a TLS server handshake on the given connection.
 func Server(c net.Conn, config *tls.Config) net.Conn {
 	tlsConn := tls.Server(c, config)
diff --git a/transport/internet/tls/tlsspoof/client_hello.go b/transport/internet/tls/tlsspoof/client_hello.go
new file mode 100644
index 000000000000..b078697c97cc
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/client_hello.go
@@ -0,0 +1,75 @@
+package tlsspoof
+
+import (
+	"bytes"
+	"context"
+	"crypto/tls"
+
+	"errors"
+	"net"
+	"time"
+)
+
+type writeOnlyConn struct {
+	net.Conn
+	w *bytes.Buffer
+}
+
+func (c *writeOnlyConn) Write(b []byte) (int, error) {
+	return c.w.Write(b)
+}
+
+func (c *writeOnlyConn) Read(b []byte) (int, error) {
+	return 0, errors.New("read from write-only conn")
+}
+
+func (c *writeOnlyConn) Close() error {
+	return nil
+}
+
+func (c *writeOnlyConn) LocalAddr() net.Addr {
+	return nil
+}
+
+func (c *writeOnlyConn) RemoteAddr() net.Addr {
+	return nil
+}
+
+func (c *writeOnlyConn) SetDeadline(t time.Time) error {
+	return nil
+}
+
+func (c *writeOnlyConn) SetReadDeadline(t time.Time) error {
+	return nil
+}
+
+func (c *writeOnlyConn) SetWriteDeadline(t time.Time) error {
+	return nil
+}
+
+// buildFakeClientHello drives crypto/tls against a write-only in-memory conn
+// to capture a generated ClientHello. CurvePreferences pins classical groups
+// to suppress Go's default X25519MLKEM768 hybrid key share; without this the
+// post-quantum public key alone (~1184 bytes) pushes the record past one MSS,
+// and middleboxes do not reassemble fragmented ClientHellos. The handshake
+// error is discarded because the stub conn's Read returns immediately.
+func buildFakeClientHello(sni string) ([]byte, error) {
+	if sni == "" {
+		return nil, errors.New("empty sni")
+	}
+	var buf bytes.Buffer
+	tlsConn := tls.Client(&writeOnlyConn{w: &buf}, &tls.Config{
+		ServerName: sni,
+		// Order matches what browsers advertised before post-quantum.
+		CurvePreferences:   []tls.CurveID{tls.X25519, tls.CurveP256, tls.CurveP384},
+		MinVersion:         tls.VersionTLS12,
+		MaxVersion:         tls.VersionTLS13,
+		NextProtos:         []string{"h2", "http/1.1"},
+		InsecureSkipVerify: true,
+	})
+	_ = tlsConn.HandshakeContext(context.Background())
+	if buf.Len() == 0 {
+		return nil, errors.New("tls ClientHello not produced")
+	}
+	return buf.Bytes(), nil
+}
diff --git a/transport/internet/tls/tlsspoof/endpoints.go b/transport/internet/tls/tlsspoof/endpoints.go
new file mode 100644
index 000000000000..ac0c30484226
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/endpoints.go
@@ -0,0 +1,27 @@
+package tlsspoof
+
+import (
+	"net"
+	"net/netip"
+
+	"errors"
+)
+
+// The returned addresses are v4-unmapped and share the same family.
+func tcpEndpoints(conn net.Conn) (*net.TCPConn, netip.AddrPort, netip.AddrPort, error) {
+	tcpConn, isTCP := conn.(*net.TCPConn)
+	if !isTCP {
+		return nil, netip.AddrPort{}, netip.AddrPort{}, errors.New("tls_spoof: underlying conn is not *net.TCPConn")
+	}
+	local := tcpConn.LocalAddr().(*net.TCPAddr).AddrPort()
+	remote := tcpConn.RemoteAddr().(*net.TCPAddr).AddrPort()
+	if !local.IsValid() || !remote.IsValid() {
+		return nil, netip.AddrPort{}, netip.AddrPort{}, errors.New("tls_spoof: invalid conn address")
+	}
+	local = netip.AddrPortFrom(local.Addr().Unmap(), local.Port())
+	remote = netip.AddrPortFrom(remote.Addr().Unmap(), remote.Port())
+	if local.Addr().Is4() != remote.Addr().Is4() {
+		return nil, netip.AddrPort{}, netip.AddrPort{}, errors.New("tls_spoof: local/remote address family mismatch")
+	}
+	return tcpConn, local, remote, nil
+}
diff --git a/transport/internet/tls/tlsspoof/packet.go b/transport/internet/tls/tlsspoof/packet.go
new file mode 100644
index 000000000000..5c23c0631ab8
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/packet.go
@@ -0,0 +1,163 @@
+package tlsspoof
+
+import (
+	"encoding/binary"
+	"net/netip"
+
+	"fmt"
+)
+
+const (
+	defaultTTL        uint8  = 64
+	defaultWindowSize uint16 = 0xFFFF
+	tcpHeaderLen             = TCPMinimumSize
+
+	tcpOptionMD5Signature       = 19
+	tcpOptionMD5SignatureLength = 18
+	tcpTimestampBackdate        = 3600000
+)
+
+type spoofPacketInfo struct {
+	seqNum  uint32
+	ackNum  uint32
+	corrupt bool
+	options []byte
+}
+
+func buildTCPSegment(
+	src netip.AddrPort,
+	dst netip.AddrPort,
+	packetInfo spoofPacketInfo,
+	payload []byte,
+) []byte {
+	if src.Addr().Is4() != dst.Addr().Is4() {
+		panic("tlsspoof: mixed IPv4/IPv6 address family")
+	}
+	var (
+		frame       []byte
+		ipHeaderLen int
+	)
+	ipPayloadLen := tcpHeaderLen + len(packetInfo.options) + len(payload)
+	if src.Addr().Is4() {
+		ipHeaderLen = IPv4MinimumSize
+		frame = make([]byte, ipHeaderLen+ipPayloadLen)
+		ip := IPv4(frame[:ipHeaderLen])
+		ip.Encode(uint16(len(frame)), 0, defaultTTL, TCPProtocolNumber, src.Addr(), dst.Addr())
+	} else {
+		ipHeaderLen = IPv6MinimumSize
+		frame = make([]byte, ipHeaderLen+ipPayloadLen)
+		ip := IPv6(frame[:ipHeaderLen])
+		ip.Encode(uint16(ipPayloadLen), TCPProtocolNumber, defaultTTL, src.Addr(), dst.Addr())
+	}
+	encodeTCP(frame, ipHeaderLen, src, dst, packetInfo, payload)
+	return frame
+}
+
+func encodeTCP(frame []byte, ipHeaderLen int, src, dst netip.AddrPort, packetInfo spoofPacketInfo, payload []byte) {
+	tcp := TCP(frame[ipHeaderLen:])
+	copy(frame[ipHeaderLen+tcpHeaderLen:], packetInfo.options)
+	optionsLen := len(packetInfo.options)
+	copy(frame[ipHeaderLen+tcpHeaderLen+optionsLen:], payload)
+	tcp.Encode(src.Port(), dst.Port(), packetInfo.seqNum, packetInfo.ackNum, uint8(tcpHeaderLen+optionsLen), TCPFlagAck|TCPFlagPsh, defaultWindowSize)
+	applyTCPChecksum(tcp, src.Addr(), dst.Addr(), payload, packetInfo.corrupt)
+}
+
+func buildSpoofFrame(method Method, src, dst netip.AddrPort, sendNext, receiveNext, timestamp uint32, tcpOptions, payload []byte) ([]byte, error) {
+	packetInfo, err := resolveSpoofPacketInfo(method, sendNext, receiveNext, timestamp, tcpOptions, payload)
+	if err != nil {
+		return nil, err
+	}
+	return buildTCPSegment(src, dst, packetInfo, payload), nil
+}
+
+// buildSpoofTCPSegment returns a TCP segment without an IP header, for
+// platforms where the kernel synthesises the IP header (darwin IPv6).
+func buildSpoofTCPSegment(method Method, src, dst netip.AddrPort, sendNext, receiveNext, timestamp uint32, payload []byte) ([]byte, error) {
+	packetInfo, err := resolveSpoofPacketInfo(method, sendNext, receiveNext, timestamp, nil, payload)
+	if err != nil {
+		return nil, err
+	}
+	segment := make([]byte, tcpHeaderLen+len(packetInfo.options)+len(payload))
+	encodeTCP(segment, 0, src, dst, packetInfo, payload)
+	return segment, nil
+}
+
+func resolveSpoofPacketInfo(method Method, sendNext, receiveNext, timestamp uint32, tcpOptions, payload []byte) (spoofPacketInfo, error) {
+	packetInfo := spoofPacketInfo{seqNum: sendNext, ackNum: receiveNext}
+	switch method {
+	case MethodWrongSequence:
+		packetInfo.seqNum = sendNext - uint32(len(payload))
+	case MethodWrongChecksum:
+		packetInfo.corrupt = true
+	case MethodWrongAcknowledgment:
+		packetInfo.ackNum = receiveNext - uint32(defaultWindowSize/2)
+	case MethodWrongMD5Sig:
+		packetInfo.options = buildMD5SignatureOptions()
+	case MethodWrongTimestamp:
+		packetInfo.options = buildWrongTimestampOptions(timestamp, tcpOptions)
+	default:
+		return packetInfo, fmt.Errorf("tls_spoof: unknown method %v", method)
+	}
+	return packetInfo, nil
+}
+
+func buildMD5SignatureOptions() []byte {
+	options := make([]byte, tcpOptionMD5SignatureLength+2)
+	options[0] = tcpOptionMD5Signature
+	options[1] = tcpOptionMD5SignatureLength
+	return options
+}
+
+func buildWrongTimestampOptions(timestamp uint32, tcpOptions []byte) []byte {
+	spoofedTimestamp := timestamp
+	if spoofedTimestamp > tcpTimestampBackdate {
+		spoofedTimestamp -= tcpTimestampBackdate
+	} else {
+		spoofedTimestamp = 0
+	}
+	if rewriteTCPOptionTimestamp(tcpOptions, spoofedTimestamp) {
+		return tcpOptions
+	}
+	options := make([]byte, TCPOptionTSLength+2)
+	EncodeTSOption(spoofedTimestamp, 0, options)
+	return options
+}
+
+// rewriteTCPOptionTimestamp finds the TS option in tcpOptions and writes
+// timestamp into its TSVal field in place. The caller must own tcpOptions
+// (parseTCPPacket already returns a private copy on Windows).
+func rewriteTCPOptionTimestamp(tcpOptions []byte, timestamp uint32) bool {
+	for i := 0; i < len(tcpOptions); {
+		switch tcpOptions[i] {
+		case TCPOptionEOL:
+			return false
+		case TCPOptionNOP:
+			i++
+			continue
+		}
+		if i+1 >= len(tcpOptions) {
+			return false
+		}
+		optionLen := int(tcpOptions[i+1])
+		if optionLen < 2 || i+optionLen > len(tcpOptions) {
+			return false
+		}
+		if tcpOptions[i] == TCPOptionTS && optionLen == TCPOptionTSLength {
+			binary.BigEndian.PutUint32(tcpOptions[i+2:], timestamp)
+			return true
+		}
+		i += optionLen
+	}
+	return false
+}
+
+func applyTCPChecksum(tcp TCP, srcAddr, dstAddr netip.Addr, payload []byte, corrupt bool) {
+	tcpLen := int(tcp.DataOffset()) + len(payload)
+	pseudo := PseudoHeaderChecksum(TCPProtocolNumber, srcAddr.AsSlice(), dstAddr.AsSlice(), uint16(tcpLen))
+	payloadChecksum := Checksum(payload, 0)
+	tcpChecksum := ^tcp.CalculateChecksum(CombineChecksum(pseudo, payloadChecksum))
+	if corrupt {
+		tcpChecksum ^= 0xFFFF
+	}
+	tcp.SetChecksum(tcpChecksum)
+}
diff --git a/transport/internet/tls/tlsspoof/raw_darwin.go b/transport/internet/tls/tlsspoof/raw_darwin.go
new file mode 100644
index 000000000000..3b45d17023be
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/raw_darwin.go
@@ -0,0 +1,198 @@
+package tlsspoof
+
+import (
+	"encoding/binary"
+	"net"
+	"net/netip"
+	"strconv"
+	"strings"
+	"sync"
+	"syscall"
+
+	"errors"
+	"fmt"
+
+	"golang.org/x/sys/unix"
+)
+
+const PlatformSupported = true
+
+// Offsets into xinpcb_n within each net.inet.tcp.pcblist_n record, identical
+// to the values used by common/process/searcher_darwin_shared.go.
+const (
+	darwinXinpgenSize       = 24
+	darwinXsocketOffset     = 104
+	darwinXinpcbForeignPort = 16
+	darwinXinpcbLocalPort   = 18
+	darwinXinpcbVFlag       = 44
+	darwinXinpcbForeignAddr = 48
+	darwinXinpcbLocalAddr   = 64
+	darwinXinpcbIPv4Offset  = 12
+
+	darwinTCPExtraSize = 208
+
+	darwinXtcpcbSndNxtOffset = 56
+	darwinXtcpcbRcvNxtOffset = 80
+)
+
+// darwinStructSize returns the size of xinpcb_n for the running Darwin kernel.
+// Darwin 22 (macOS 13 Ventura) grew the struct from 384 to 408 bytes; there is
+// no ABI-stable way to read it, so we key off the kernel version.
+var darwinStructSize = sync.OnceValues(func() (int, error) {
+	value, err := syscall.Sysctl("kern.osrelease")
+	if err != nil {
+		return 0, func(err error, m string) error { return err }(err, "sysctl kern.osrelease")
+	}
+	major, _, ok := strings.Cut(value, ".")
+	if !ok {
+		return 0, fmt.Errorf("unexpected kern.osrelease format: %s", value)
+	}
+	n, err := strconv.ParseInt(major, 10, 64)
+	if err != nil {
+		return 0, func(err error, m string) error { return err }(err, "parse kern.osrelease major version: ")
+	}
+	if n >= 22 {
+		return 408, nil
+	}
+	return 384, nil
+})
+
+type darwinSpoofer struct {
+	method      Method
+	src         netip.AddrPort
+	dst         netip.AddrPort
+	rawFD       int
+	rawSockAddr unix.Sockaddr
+	sendNext    uint32
+	receiveNext uint32
+}
+
+func newRawSpoofer(conn net.Conn, method Method) (rawSpoofer, error) {
+	if method == MethodWrongTimestamp {
+		return nil, errors.New("tls_spoof: wrong-timestamp is not supported on macOS")
+	}
+	_, src, dst, err := tcpEndpoints(conn)
+	if err != nil {
+		return nil, err
+	}
+	fd, sockaddr, err := openDarwinRawSocket(src, dst)
+	if err != nil {
+		return nil, err
+	}
+	sendNext, receiveNext, err := readDarwinTCPSequence(src, dst)
+	if err != nil {
+		unix.Close(fd)
+		return nil, err
+	}
+	return &darwinSpoofer{
+		method:      method,
+		src:         src,
+		dst:         dst,
+		rawFD:       fd,
+		rawSockAddr: sockaddr,
+		sendNext:    sendNext,
+		receiveNext: receiveNext,
+	}, nil
+}
+
+// readDarwinTCPSequence scans net.inet.tcp.pcblist_n for the PCB that matches
+// src -> dst and returns (snd_nxt, rcv_nxt). These live in xtcpcb_n at the end
+// of each record; see darwin-xnu bsd/netinet/in_pcblist.c:get_pcblist_n.
+func readDarwinTCPSequence(src, dst netip.AddrPort) (uint32, uint32, error) {
+	buffer, err := unix.SysctlRaw("net.inet.tcp.pcblist_n")
+	if err != nil {
+		return 0, 0, func(err error, m string) error { return err }(err, "sysctl net.inet.tcp.pcblist_n")
+	}
+	structSize, err := darwinStructSize()
+	if err != nil {
+		return 0, 0, err
+	}
+	itemSize := structSize + darwinTCPExtraSize
+	for i := darwinXinpgenSize; i+itemSize <= len(buffer); i += itemSize {
+		inpcb := buffer[i : i+darwinXsocketOffset]
+		xtcpcb := buffer[i+structSize : i+itemSize]
+		localPort := binary.BigEndian.Uint16(inpcb[darwinXinpcbLocalPort : darwinXinpcbLocalPort+2])
+		remotePort := binary.BigEndian.Uint16(inpcb[darwinXinpcbForeignPort : darwinXinpcbForeignPort+2])
+		if localPort != src.Port() || remotePort != dst.Port() {
+			continue
+		}
+		versionFlag := inpcb[darwinXinpcbVFlag]
+		var localAddr, remoteAddr netip.Addr
+		switch {
+		case versionFlag&0x1 != 0:
+			localAddr = netip.AddrFrom4([4]byte(inpcb[darwinXinpcbLocalAddr+darwinXinpcbIPv4Offset : darwinXinpcbLocalAddr+darwinXinpcbIPv4Offset+4]))
+			remoteAddr = netip.AddrFrom4([4]byte(inpcb[darwinXinpcbForeignAddr+darwinXinpcbIPv4Offset : darwinXinpcbForeignAddr+darwinXinpcbIPv4Offset+4]))
+		case versionFlag&0x2 != 0:
+			localAddr = netip.AddrFrom16([16]byte(inpcb[darwinXinpcbLocalAddr : darwinXinpcbLocalAddr+16]))
+			remoteAddr = netip.AddrFrom16([16]byte(inpcb[darwinXinpcbForeignAddr : darwinXinpcbForeignAddr+16]))
+		default:
+			continue
+		}
+		if localAddr.Unmap() != src.Addr() || remoteAddr.Unmap() != dst.Addr() {
+			continue
+		}
+		sendNext := binary.NativeEndian.Uint32(xtcpcb[darwinXtcpcbSndNxtOffset : darwinXtcpcbSndNxtOffset+4])
+		receiveNext := binary.NativeEndian.Uint32(xtcpcb[darwinXtcpcbRcvNxtOffset : darwinXtcpcbRcvNxtOffset+4])
+		return sendNext, receiveNext, nil
+	}
+	return 0, 0, fmt.Errorf("tls_spoof: connection %v->%v not found in pcblist_n", src, dst)
+}
+
+func openDarwinRawSocket(src, dst netip.AddrPort) (int, unix.Sockaddr, error) {
+	if dst.Addr().Is4() {
+		return openIPv4RawSocket(dst)
+	}
+	// macOS does not accept IPV6_HDRINCL on AF_INET6 SOCK_RAW IPPROTO_TCP
+	// sockets, so the kernel builds the IPv6 header itself. Bind to the real
+	// connection's source address so in6_selectsrc returns it, and rely on
+	// in6p_cksum defaulting to -1 so the user-supplied TCP checksum is
+	// preserved (including deliberately corrupted ones).
+	fd, err := unix.Socket(unix.AF_INET6, unix.SOCK_RAW, unix.IPPROTO_TCP)
+	if err != nil {
+		return -1, nil, func(err error, m string) error { return err }(err, "open AF_INET6 SOCK_RAW")
+	}
+	err = unix.Bind(fd, &unix.SockaddrInet6{Addr: src.Addr().As16()})
+	if err != nil {
+		unix.Close(fd)
+		return -1, nil, func(err error, m string) error { return err }(err, "bind AF_INET6 SOCK_RAW")
+	}
+	sockaddr := &unix.SockaddrInet6{Port: int(dst.Port()), Addr: dst.Addr().As16()}
+	return fd, sockaddr, nil
+}
+
+func (s *darwinSpoofer) Inject(payload []byte) error {
+	if !s.src.Addr().Is4() {
+		segment, err := buildSpoofTCPSegment(s.method, s.src, s.dst, s.sendNext, s.receiveNext, 0, payload)
+		if err != nil {
+			return err
+		}
+		err = unix.Sendto(s.rawFD, segment, 0, s.rawSockAddr)
+		if err != nil {
+			return func(err error, m string) error { return err }(err, "sendto raw socket")
+		}
+		return nil
+	}
+	frame, err := buildSpoofFrame(s.method, s.src, s.dst, s.sendNext, s.receiveNext, 0, nil, payload)
+	if err != nil {
+		return err
+	}
+	// Darwin inherits the historical BSD quirk: with IP_HDRINCL the kernel
+	// expects ip_len and ip_off in host byte order, not network byte order.
+	ip := IPv4(frame)
+	binary.NativeEndian.PutUint16(ip[2:4], ip.TotalLength())
+	binary.NativeEndian.PutUint16(ip[6:8], uint16(ip.Flags())<<13|ip.FragmentOffset())
+	err = unix.Sendto(s.rawFD, frame, 0, s.rawSockAddr)
+	if err != nil {
+		return func(err error, m string) error { return err }(err, "sendto raw socket")
+	}
+	return nil
+}
+
+func (s *darwinSpoofer) Close() error {
+	if s.rawFD < 0 {
+		return nil
+	}
+	err := unix.Close(s.rawFD)
+	s.rawFD = -1
+	return err
+}
diff --git a/transport/internet/tls/tlsspoof/raw_freebsd.go b/transport/internet/tls/tlsspoof/raw_freebsd.go
new file mode 100644
index 000000000000..0f39a0ee5c39
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/raw_freebsd.go
@@ -0,0 +1,172 @@
+package tlsspoof
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"net"
+	"net/netip"
+	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+const PlatformSupported = true
+
+// FreeBSD tcp_info offsets for snd_nxt and rcv_nxt.
+// Derived from FreeBSD sys/netinet/tcp.h struct tcp_info layout.
+//
+//	struct tcp_info {
+//	    u8 state, __ca, __retrans, __probes, __backoff, opts, wscale  = 8 bytes (with pad)
+//	    u32 rto, __ato, snd_mss, rcv_mss                             = 16 bytes (offset 8)
+//	    u32 __unacked, __sacked, __lost, __retrans, __fackets         = 20 bytes (offset 24)
+//	    u32 __last_data_sent, __last_ack_sent, last_data_recv, __last_ack_recv = 16 bytes (offset 44)
+//	    u32 __pmtu, __rcv_ssthresh, rtt, rttvar, snd_ssthresh, snd_cwnd, __advmss, __reordering = 32 bytes (offset 60)
+//	    u32 __rcv_rtt, rcv_space                                     = 8 bytes  (offset 92)
+//	    u32 snd_wnd, snd_bwnd                                        = 8 bytes  (offset 100)
+//	    u32 snd_nxt, rcv_nxt                                         = 8 bytes  (offset 108)
+//	    ... remaining fields
+//	}
+const (
+	freebsdTCPInfoSndNxtOffset = 108
+	freebsdTCPInfoRcvNxtOffset = 112
+	freebsdTCPInfoMinSize      = 116 // must read at least through rcv_nxt
+)
+
+type freebsdSpoofer struct {
+	method      Method
+	src         netip.AddrPort
+	dst         netip.AddrPort
+	rawFD       int
+	rawSockAddr unix.Sockaddr
+	sendNext    uint32
+	receiveNext uint32
+}
+
+func newRawSpoofer(conn net.Conn, method Method) (rawSpoofer, error) {
+	if method == MethodWrongTimestamp {
+		return nil, errors.New("tls_spoof: wrong-timestamp is not supported on FreeBSD")
+	}
+	tcpConn, src, dst, err := tcpEndpoints(conn)
+	if err != nil {
+		return nil, err
+	}
+	fd, sockaddr, err := openFreeBSDRawSocket(src, dst)
+	if err != nil {
+		return nil, err
+	}
+	sendNext, receiveNext, err := readFreeBSDTCPSequence(tcpConn)
+	if err != nil {
+		unix.Close(fd)
+		return nil, err
+	}
+	return &freebsdSpoofer{
+		method:      method,
+		src:         src,
+		dst:         dst,
+		rawFD:       fd,
+		rawSockAddr: sockaddr,
+		sendNext:    sendNext,
+		receiveNext: receiveNext,
+	}, nil
+}
+
+// readFreeBSDTCPSequence retrieves snd_nxt and rcv_nxt via TCP_INFO getsockopt.
+func readFreeBSDTCPSequence(conn *net.TCPConn) (uint32, uint32, error) {
+	raw, err := conn.SyscallConn()
+	if err != nil {
+		return 0, 0, fmt.Errorf("tls_spoof: SyscallConn: %w", err)
+	}
+	var sendNext, receiveNext uint32
+	var sockErr error
+	err = raw.Control(func(fd uintptr) {
+		buf := make([]byte, 256) // generous buffer for tcp_info
+		bufLen := uint32(len(buf))
+		_, _, errno := syscall.Syscall6(
+			syscall.SYS_GETSOCKOPT,
+			fd,
+			uintptr(syscall.IPPROTO_TCP),
+			uintptr(0x20), // TCP_INFO = 0x20
+			uintptr(unsafe.Pointer(&buf[0])),
+			uintptr(unsafe.Pointer(&bufLen)),
+			0,
+		)
+		if errno != 0 {
+			sockErr = fmt.Errorf("tls_spoof: getsockopt TCP_INFO: %w", errno)
+			return
+		}
+		if bufLen < freebsdTCPInfoMinSize {
+			sockErr = fmt.Errorf("tls_spoof: TCP_INFO too short: %d < %d", bufLen, freebsdTCPInfoMinSize)
+			return
+		}
+		sendNext = binary.NativeEndian.Uint32(buf[freebsdTCPInfoSndNxtOffset : freebsdTCPInfoSndNxtOffset+4])
+		receiveNext = binary.NativeEndian.Uint32(buf[freebsdTCPInfoRcvNxtOffset : freebsdTCPInfoRcvNxtOffset+4])
+	})
+	if err != nil {
+		return 0, 0, err
+	}
+	if sockErr != nil {
+		return 0, 0, sockErr
+	}
+	return sendNext, receiveNext, nil
+}
+
+func openFreeBSDRawSocket(src, dst netip.AddrPort) (int, unix.Sockaddr, error) {
+	if dst.Addr().Is4() {
+		return openIPv4RawSocket(dst)
+	}
+	// FreeBSD, like macOS, does not support IPV6_HDRINCL on SOCK_RAW/IPPROTO_TCP.
+	// The kernel constructs the IPv6 header. Bind to the source address
+	// and let the kernel fill in the IPv6 header automatically.
+	fd, err := unix.Socket(unix.AF_INET6, unix.SOCK_RAW, unix.IPPROTO_TCP)
+	if err != nil {
+		return -1, nil, fmt.Errorf("tls_spoof: open AF_INET6 SOCK_RAW: %w", err)
+	}
+	err = unix.Bind(fd, &unix.SockaddrInet6{Addr: src.Addr().As16()})
+	if err != nil {
+		unix.Close(fd)
+		return -1, nil, fmt.Errorf("tls_spoof: bind AF_INET6 SOCK_RAW: %w", err)
+	}
+	sockaddr := &unix.SockaddrInet6{Port: int(dst.Port()), Addr: dst.Addr().As16()}
+	return fd, sockaddr, nil
+}
+
+func (s *freebsdSpoofer) Inject(payload []byte) error {
+	if !s.src.Addr().Is4() {
+		// IPv6: kernel builds the IP header, we supply TCP segment only.
+		segment, err := buildSpoofTCPSegment(s.method, s.src, s.dst, s.sendNext, s.receiveNext, 0, payload)
+		if err != nil {
+			return err
+		}
+		err = unix.Sendto(s.rawFD, segment, 0, s.rawSockAddr)
+		if err != nil {
+			return fmt.Errorf("tls_spoof: sendto raw socket: %w", err)
+		}
+		return nil
+	}
+	// IPv4: we build the full IP+TCP frame with IP_HDRINCL.
+	frame, err := buildSpoofFrame(s.method, s.src, s.dst, s.sendNext, s.receiveNext, 0, nil, payload)
+	if err != nil {
+		return err
+	}
+	// FreeBSD inherits the historical BSD quirk: with IP_HDRINCL the kernel
+	// expects ip_len and ip_off in host byte order, not network byte order.
+	ip := IPv4(frame)
+	binary.NativeEndian.PutUint16(ip[2:4], ip.TotalLength())
+	binary.NativeEndian.PutUint16(ip[6:8], uint16(ip.Flags())<<13|ip.FragmentOffset())
+	err = unix.Sendto(s.rawFD, frame, 0, s.rawSockAddr)
+	if err != nil {
+		return fmt.Errorf("tls_spoof: sendto raw socket: %w", err)
+	}
+	return nil
+}
+
+func (s *freebsdSpoofer) Close() error {
+	if s.rawFD < 0 {
+		return nil
+	}
+	err := unix.Close(s.rawFD)
+	s.rawFD = -1
+	return err
+}
diff --git a/transport/internet/tls/tlsspoof/raw_linux.go b/transport/internet/tls/tlsspoof/raw_linux.go
new file mode 100644
index 000000000000..dc5c7311869c
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/raw_linux.go
@@ -0,0 +1,166 @@
+package tlsspoof
+
+import (
+	"fmt"
+	"net"
+	"net/netip"
+
+	"golang.org/x/sys/unix"
+)
+
+const PlatformSupported = true
+
+const (
+	// Values of enum { TCP_NO_QUEUE, TCP_RECV_QUEUE, TCP_SEND_QUEUE } from
+	// include/net/tcp.h; not exported by golang.org/x/sys/unix.
+	tcpRecvQueue = 1
+	tcpSendQueue = 2
+)
+
+type linuxSpoofer struct {
+	method      Method
+	src         netip.AddrPort
+	dst         netip.AddrPort
+	rawFD       int
+	rawSockAddr unix.Sockaddr
+	sendNext    uint32
+	receiveNext uint32
+	timestamp   uint32
+}
+
+func newRawSpoofer(conn net.Conn, method Method) (rawSpoofer, error) {
+	tcpConn, src, dst, err := tcpEndpoints(conn)
+	if err != nil {
+		return nil, err
+	}
+	fd, sockaddr, err := openLinuxRawSocket(dst)
+	if err != nil {
+		return nil, err
+	}
+	spoofer := &linuxSpoofer{
+		method:      method,
+		src:         src,
+		dst:         dst,
+		rawFD:       fd,
+		rawSockAddr: sockaddr,
+	}
+	err = spoofer.loadSequenceNumbers(tcpConn)
+	if err != nil {
+		unix.Close(fd)
+		return nil, err
+	}
+	return spoofer, nil
+}
+
+func openLinuxRawSocket(dst netip.AddrPort) (int, unix.Sockaddr, error) {
+	if dst.Addr().Is4() {
+		return openIPv4RawSocket(dst)
+	}
+	fd, err := unix.Socket(unix.AF_INET6, unix.SOCK_RAW, unix.IPPROTO_TCP)
+	if err != nil {
+		return -1, nil, func(err error, m string) error { return err }(err, "open AF_INET6 SOCK_RAW")
+	}
+	err = unix.SetsockoptInt(fd, unix.IPPROTO_IPV6, unix.IPV6_HDRINCL, 1)
+	if err != nil {
+		unix.Close(fd)
+		return -1, nil, func(err error, m string) error { return err }(err, "set IPV6_HDRINCL")
+	}
+	// Linux raw IPv6 sockets interpret sin6_port as a nexthdr protocol number
+	// (see raw(7)); any value other than 0 or the socket's IPPROTO_TCP causes
+	// sendto to fail with EINVAL. The destination is already encoded in the
+	// user-supplied IPv6 header under IPV6_HDRINCL.
+	sockaddr := &unix.SockaddrInet6{Addr: dst.Addr().As16()}
+	return fd, sockaddr, nil
+}
+
+// loadSequenceNumbers puts the socket briefly into TCP_REPAIR mode to read
+// snd_nxt and rcv_nxt from the kernel. TCP_REPAIR requires CAP_NET_ADMIN;
+// callers must run as root or grant both CAP_NET_RAW and CAP_NET_ADMIN.
+//
+// If the TCP_REPAIR_OFF revert fails, the socket would stay in TCP_REPAIR
+// state and subsequent Write() calls would silently buffer instead of sending.
+// Surface that error so callers can abort.
+func (s *linuxSpoofer) loadSequenceNumbers(tcpConn *net.TCPConn) error {
+	rawConn, err := tcpConn.SyscallConn()
+	if err != nil {
+		return err
+	}
+	var ctrlErr error
+	err = rawConn.Control(func(raw uintptr) {
+		fd := int(raw)
+
+		if s.method == MethodWrongTimestamp {
+			timestamp, tsErr := unix.GetsockoptInt(fd, unix.IPPROTO_TCP, unix.TCP_TIMESTAMP)
+			if tsErr != nil {
+				ctrlErr = fmt.Errorf("tls_spoof: read timestamp: %w", tsErr)
+				return
+			}
+			s.timestamp = uint32(timestamp)
+		}
+
+		ctrlErr = unix.SetsockoptInt(fd, unix.IPPROTO_TCP, unix.TCP_REPAIR, unix.TCP_REPAIR_ON)
+		if ctrlErr != nil {
+			ctrlErr = fmt.Errorf("tls_spoof: enter TCP_REPAIR (need CAP_NET_ADMIN): %w", ctrlErr)
+			return
+		}
+		defer func() {
+			offErr := unix.SetsockoptInt(fd, unix.IPPROTO_TCP, unix.TCP_REPAIR, unix.TCP_REPAIR_OFF)
+			if offErr != nil {
+				offErr = fmt.Errorf("tls_spoof: leave TCP_REPAIR: %w", offErr)
+				if ctrlErr == nil {
+					ctrlErr = offErr
+				} else {
+					ctrlErr = fmt.Errorf("%v; also %w", ctrlErr, offErr)
+				}
+			}
+		}()
+
+		ctrlErr = unix.SetsockoptInt(fd, unix.IPPROTO_TCP, unix.TCP_REPAIR_QUEUE, tcpSendQueue)
+		if ctrlErr != nil {
+			ctrlErr = fmt.Errorf("tls_spoof: select TCP_SEND_QUEUE: %w", ctrlErr)
+			return
+		}
+		sendSequence, seqErr := unix.GetsockoptInt(fd, unix.IPPROTO_TCP, unix.TCP_QUEUE_SEQ)
+		if seqErr != nil {
+			ctrlErr = fmt.Errorf("tls_spoof: read send queue sequence: %w", seqErr)
+			return
+		}
+		ctrlErr = unix.SetsockoptInt(fd, unix.IPPROTO_TCP, unix.TCP_REPAIR_QUEUE, tcpRecvQueue)
+		if ctrlErr != nil {
+			ctrlErr = fmt.Errorf("tls_spoof: select TCP_RECV_QUEUE: %w", ctrlErr)
+			return
+		}
+		receiveSequence, seqErr := unix.GetsockoptInt(fd, unix.IPPROTO_TCP, unix.TCP_QUEUE_SEQ)
+		if seqErr != nil {
+			ctrlErr = fmt.Errorf("tls_spoof: read recv queue sequence: %w", seqErr)
+			return
+		}
+		s.sendNext = uint32(sendSequence)
+		s.receiveNext = uint32(receiveSequence)
+	})
+	if err != nil {
+		return err
+	}
+	return ctrlErr
+}
+
+func (s *linuxSpoofer) Inject(payload []byte) error {
+	frame, err := buildSpoofFrame(s.method, s.src, s.dst, s.sendNext, s.receiveNext, s.timestamp, nil, payload)
+	if err != nil {
+		return err
+	}
+	err = unix.Sendto(s.rawFD, frame, 0, s.rawSockAddr)
+	if err != nil {
+		return func(err error, m string) error { return err }(err, "sendto raw socket")
+	}
+	return nil
+}
+
+func (s *linuxSpoofer) Close() error {
+	if s.rawFD < 0 {
+		return nil
+	}
+	err := unix.Close(s.rawFD)
+	s.rawFD = -1
+	return err
+}
diff --git a/transport/internet/tls/tlsspoof/raw_stub.go b/transport/internet/tls/tlsspoof/raw_stub.go
new file mode 100644
index 000000000000..78be3c23391d
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/raw_stub.go
@@ -0,0 +1,15 @@
+//go:build !linux && !darwin && !freebsd && !(windows && (amd64 || 386))
+
+package tlsspoof
+
+import (
+	"net"
+
+	"errors"
+)
+
+const PlatformSupported = false
+
+func newRawSpoofer(conn net.Conn, method Method) (rawSpoofer, error) {
+	return nil, errors.New("tls_spoof: unsupported platform")
+}
diff --git a/transport/internet/tls/tlsspoof/raw_unix.go b/transport/internet/tls/tlsspoof/raw_unix.go
new file mode 100644
index 000000000000..7d5c32e3b5ef
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/raw_unix.go
@@ -0,0 +1,24 @@
+//go:build linux || darwin || freebsd
+
+package tlsspoof
+
+import (
+	"net/netip"
+
+	"golang.org/x/sys/unix"
+)
+
+func openIPv4RawSocket(dst netip.AddrPort) (int, unix.Sockaddr, error) {
+	fd, err := unix.Socket(unix.AF_INET, unix.SOCK_RAW, unix.IPPROTO_TCP)
+	if err != nil {
+		return -1, nil, func(err error, m string) error { return err }(err, "open AF_INET SOCK_RAW")
+	}
+	err = unix.SetsockoptInt(fd, unix.IPPROTO_IP, unix.IP_HDRINCL, 1)
+	if err != nil {
+		unix.Close(fd)
+		return -1, nil, func(err error, m string) error { return err }(err, "set IP_HDRINCL")
+	}
+	sockaddr := &unix.SockaddrInet4{Port: int(dst.Port())}
+	sockaddr.Addr = dst.Addr().As4()
+	return fd, sockaddr, nil
+}
diff --git a/transport/internet/tls/tlsspoof/raw_windows.go b/transport/internet/tls/tlsspoof/raw_windows.go
new file mode 100644
index 000000000000..17878ffce3dd
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/raw_windows.go
@@ -0,0 +1,234 @@
+//go:build windows && (amd64 || 386)
+
+package tlsspoof
+
+import (
+	"errors"
+	"net"
+	"net/netip"
+	"slices"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/xtls/xray-core/transport/internet/tls/tlsspoof/windivert"
+	"golang.org/x/sys/windows"
+)
+
+const PlatformSupported = true
+
+// closeGracePeriod caps how long Close() waits for the divert goroutine to
+// observe the kernel-emitted real ClientHello and perform the reorder
+// (fake → real). In practice this completes in microseconds; the cap
+// bounds the pathological case where the kernel buffers the packet.
+const closeGracePeriod = 2 * time.Second
+
+// windowsSpoofer uses a single WinDivert handle for both capture and
+// injection. Sequential Send() calls on one handle traverse one driver queue,
+// so the fake provably precedes the released real on the wire — a guarantee
+// two separate handles cannot make because cross-handle order depends on the
+// scheduler.
+type windowsSpoofer struct {
+	method   Method
+	src, dst netip.AddrPort
+	divertH  *windivert.Handle
+
+	fakeReady chan []byte   // buffered(1): staged by Inject
+	done      chan struct{} // closed by run() on exit
+	closeOnce sync.Once
+	runErr    atomic.Pointer[error]
+}
+
+func newRawSpoofer(conn net.Conn, method Method) (rawSpoofer, error) {
+	_, src, dst, err := tcpEndpoints(conn)
+	if err != nil {
+		return nil, err
+	}
+	filter, err := windivert.OutboundTCP(src, dst)
+	if err != nil {
+		return nil, err
+	}
+	divertH, err := windivert.Open(filter, windivert.LayerNetwork, 0, 0)
+	if err != nil {
+		return nil, err
+	}
+	s := &windowsSpoofer{
+		method:    method,
+		src:       src,
+		dst:       dst,
+		divertH:   divertH,
+		fakeReady: make(chan []byte, 1),
+		done:      make(chan struct{}),
+	}
+	go s.run()
+	return s, nil
+}
+
+func (s *windowsSpoofer) Inject(payload []byte) error {
+	select {
+	case s.fakeReady <- payload:
+		return nil
+	case <-s.done:
+		if p := s.runErr.Load(); p != nil {
+			return *p
+		}
+		return errors.New("tls_spoof: spoofer closed before Inject")
+	}
+}
+
+func (s *windowsSpoofer) Close() error {
+	s.closeOnce.Do(func() {
+		// Give run() a grace window to finish handling the real packet.
+		select {
+		case <-s.done:
+		case <-time.After(closeGracePeriod):
+			// Force Recv() to return by closing the divert handle.
+			s.divertH.Close()
+			<-s.done
+		}
+	})
+	if p := s.runErr.Load(); p != nil {
+		return *p
+	}
+	return nil
+}
+
+func (s *windowsSpoofer) recordErr(err error) { s.runErr.Store(&err) }
+
+func (s *windowsSpoofer) run() {
+	defer close(s.done)
+	defer s.divertH.Close()
+
+	buf := make([]byte, windivert.MTUMax)
+	for {
+		n, addr, err := s.divertH.Recv(buf)
+		if err != nil {
+			if errors.Is(err, windows.ERROR_OPERATION_ABORTED) ||
+				errors.Is(err, windows.ERROR_NO_DATA) {
+				return
+			}
+			s.recordErr(err)
+			return
+		}
+		pkt := buf[:n]
+		seq, ack, tcpOptions, payloadLen, ok := parseTCPPacket(pkt, addr.IPv6())
+		if !ok {
+			// Our filter is OutboundTCP(src, dst); a non-TCP or truncated
+			// match means driver state is suspect. Re-inject so the kernel
+			// still sees the byte stream, then abort — continuing would risk
+			// reordering against an unknown reference point.
+			_, sendErr := s.divertH.Send(pkt, &addr)
+			if sendErr != nil {
+				s.recordErr(sendErr)
+				return
+			}
+			s.recordErr(errors.New("windivert received malformed packet matching spoof filter"))
+			return
+		}
+		if payloadLen == 0 {
+			// Handshake ACK, keepalive, FIN — pass through unchanged.
+			_, err := s.divertH.Send(pkt, &addr)
+			if err != nil {
+				s.recordErr(err)
+				return
+			}
+			continue
+		}
+
+		// Non-empty outbound TCP payload = the real ClientHello.
+		var fake []byte
+		select {
+		case fake = <-s.fakeReady:
+		default:
+			// Inject() not yet called — pass through and keep observing.
+			_, err := s.divertH.Send(pkt, &addr)
+			if err != nil {
+				s.recordErr(err)
+				return
+			}
+			continue
+		}
+
+		var timestamp uint32
+		if tsVal, hasTS := ParseTCPOptions(tcpOptions); hasTS {
+			timestamp = tsVal
+		}
+		frame, err := buildSpoofFrame(s.method, s.src, s.dst, seq, ack, timestamp, tcpOptions, fake)
+		if err != nil {
+			s.recordErr(err)
+			return
+		}
+		fakeAddr := addr // inherit Outbound, IfIdx
+		// buildSpoofFrame emits ready-to-wire bytes. The driver recomputes
+		// checksums on Send when TCPChecksum/IPChecksum are 0 — which would
+		// overwrite the intentionally corrupt checksum in WrongChecksum mode.
+		// Force both to 1 to keep our bytes intact.
+		fakeAddr.SetIPChecksum(true)
+		fakeAddr.SetTCPChecksum(true)
+		_, err = s.divertH.Send(frame, &fakeAddr)
+		if err != nil {
+			s.recordErr(err)
+			return
+		}
+		_, err = s.divertH.Send(pkt, &addr)
+		if err != nil {
+			s.recordErr(err)
+			return
+		}
+		return // single-shot reorder complete
+	}
+}
+
+func parseTCPPacket(pkt []byte, isV6 bool) (seq, ack uint32, options []byte, payloadLen int, ok bool) {
+	if isV6 {
+		if len(pkt) < IPv6MinimumSize+TCPMinimumSize {
+			return 0, 0, nil, 0, false
+		}
+		ip := IPv6(pkt)
+		if ip.TransportProtocol() != TCPProtocolNumber {
+			return 0, 0, nil, 0, false
+		}
+		tcp := TCP(pkt[IPv6MinimumSize:])
+		tcpHdr := int(tcp.DataOffset())
+		if tcpHdr < TCPMinimumSize || IPv6MinimumSize+tcpHdr > len(pkt) {
+			return 0, 0, nil, 0, false
+		}
+		total := IPv6MinimumSize + int(ip.PayloadLength())
+		if total == IPv6MinimumSize || total > len(pkt) {
+			total = len(pkt)
+		}
+		if total < IPv6MinimumSize+tcpHdr {
+			return 0, 0, nil, 0, false
+		}
+		return tcp.SequenceNumber(), tcp.AckNumber(), slices.Clone(tcp.Options()),
+			total - IPv6MinimumSize - tcpHdr, true
+	}
+	if len(pkt) < IPv4MinimumSize+TCPMinimumSize {
+		return 0, 0, nil, 0, false
+	}
+	ip := IPv4(pkt)
+	if ip.Protocol() != TCPProtocolNumber {
+		return 0, 0, nil, 0, false
+	}
+	ihl := int(ip.HeaderLength())
+	// ihl+TCPMinimumSize guards the TCP-header field reads below; without
+	// this, an IPv4 packet with options (ihl>20) against a 40-byte buffer
+	// reads past the TCP slice when calling DataOffset.
+	if ihl < IPv4MinimumSize || ihl+TCPMinimumSize > len(pkt) {
+		return 0, 0, nil, 0, false
+	}
+	tcp := TCP(pkt[ihl:])
+	tcpHdr := int(tcp.DataOffset())
+	if tcpHdr < TCPMinimumSize || ihl+tcpHdr > len(pkt) {
+		return 0, 0, nil, 0, false
+	}
+	total := int(ip.TotalLength())
+	if total == 0 || total > len(pkt) {
+		total = len(pkt)
+	}
+	if total < ihl+tcpHdr {
+		return 0, 0, nil, 0, false
+	}
+	return tcp.SequenceNumber(), tcp.AckNumber(), slices.Clone(tcp.Options()),
+		total - ihl - tcpHdr, true
+}
diff --git a/transport/internet/tls/tlsspoof/spoof.go b/transport/internet/tls/tlsspoof/spoof.go
new file mode 100644
index 000000000000..6a9eae93a45b
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/spoof.go
@@ -0,0 +1,182 @@
+package tlsspoof
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"runtime"
+	"syscall"
+)
+
+type Method int
+
+const (
+	MethodWrongSequence Method = iota
+	MethodWrongChecksum
+	MethodWrongAcknowledgment
+	MethodWrongMD5Sig
+	MethodWrongTimestamp
+)
+
+const (
+	MethodNameWrongSequence       = "wrong-sequence"
+	MethodNameWrongChecksum       = "wrong-checksum"
+	MethodNameWrongAcknowledgment = "wrong-ack"
+	MethodNameWrongMD5Sig         = "wrong-md5"
+	MethodNameWrongTimestamp      = "wrong-timestamp"
+)
+
+func ParseOptions(spoof, method string) (string, Method, error) {
+	if spoof == "" {
+		if method != "" {
+			return "", 0, errors.New("spoof_method requires spoof")
+		}
+		return "", 0, nil
+	}
+	if net.ParseIP(spoof) != nil {
+		return "", 0, errors.New("tls_spoof: IP-literal server names are not allowed")
+	}
+	if !PlatformSupported {
+		return "", 0, errors.New("tls_spoof is not supported on this platform")
+	}
+	parsedMethod, err := ParseMethod(method)
+	if err != nil {
+		return "", 0, err
+	}
+	return spoof, parsedMethod, nil
+}
+
+func ParseMethod(s string) (Method, error) {
+	switch s {
+	case "", MethodNameWrongSequence:
+		return MethodWrongSequence, nil
+	case MethodNameWrongChecksum:
+		return MethodWrongChecksum, nil
+	case MethodNameWrongAcknowledgment:
+		return MethodWrongAcknowledgment, nil
+	case MethodNameWrongMD5Sig:
+		return MethodWrongMD5Sig, nil
+	case MethodNameWrongTimestamp:
+		return MethodWrongTimestamp, nil
+	default:
+		return 0, fmt.Errorf("tls_spoof: unknown method: %s", s)
+	}
+}
+
+func (m Method) String() string {
+	switch m {
+	case MethodWrongSequence:
+		return MethodNameWrongSequence
+	case MethodWrongChecksum:
+		return MethodNameWrongChecksum
+	case MethodWrongAcknowledgment:
+		return MethodNameWrongAcknowledgment
+	case MethodWrongMD5Sig:
+		return MethodNameWrongMD5Sig
+	case MethodWrongTimestamp:
+		return MethodNameWrongTimestamp
+	default:
+		return "unknown"
+	}
+}
+
+type rawSpoofer interface {
+	Inject(payload []byte) error
+	Close() error
+}
+
+type Conn struct {
+	net.Conn
+	spoofer        rawSpoofer
+	fakeHello      []byte
+	injectionCount int
+	maxInjections  int // how many times to inject; default 1
+}
+
+// NewConn wraps a connection with TLS spoofing. maxInjections controls how
+// many Write() calls will trigger a fake ClientHello injection (0 or 1 = single-shot).
+func NewConn(conn net.Conn, method Method, fakeSNI string, maxInjections int) (*Conn, error) {
+	spoofer, err := newRawSpoofer(conn, method)
+	if err != nil {
+		return nil, wrapPermissionError(err)
+	}
+	result, err := newConn(conn, spoofer, fakeSNI, maxInjections)
+	if err != nil {
+		spoofer.Close()
+		return nil, err
+	}
+	return result, nil
+}
+
+func newConn(conn net.Conn, spoofer rawSpoofer, fakeSNI string, maxInjections int) (*Conn, error) {
+	fakeHello, err := buildFakeClientHello(fakeSNI)
+	if err != nil {
+		return nil, func(err error, m string) error { return err }(err, "tls_spoof: build fake ClientHello")
+	}
+	if maxInjections <= 0 {
+		maxInjections = 1
+	}
+	return &Conn{
+		Conn:          conn,
+		spoofer:       spoofer,
+		fakeHello:     fakeHello,
+		maxInjections: maxInjections,
+	}, nil
+}
+
+func (c *Conn) Write(b []byte) (n int, err error) {
+	if c.injectionCount >= c.maxInjections {
+		return c.Conn.Write(b)
+	}
+	err = c.spoofer.Inject(c.fakeHello)
+	if err != nil {
+		return 0, func(err error, m string) error { return err }(err, "tls_spoof: inject")
+	}
+	c.injectionCount++
+	if c.injectionCount >= c.maxInjections {
+		closeErr := c.spoofer.Close()
+		if closeErr != nil {
+			return 0, func(err error, m string) error { return err }(closeErr, "tls_spoof: close spoofer")
+		}
+	}
+	return c.Conn.Write(b)
+}
+
+func (c *Conn) Close() error {
+	return func(e1, e2 error) error {
+		if e1 != nil {
+			return e1
+		}
+		return e2
+	}(c.Conn.Close(), c.spoofer.Close())
+}
+
+func (c *Conn) ReaderReplaceable() bool {
+	return true
+}
+
+func (c *Conn) WriterReplaceable() bool {
+	return c.injectionCount >= c.maxInjections
+}
+
+func (c *Conn) Upstream() any {
+	return c.Conn
+}
+
+// wrapPermissionError adds platform-specific hints when the spoofer fails
+// due to insufficient privileges.
+func wrapPermissionError(err error) error {
+	if !errors.Is(err, syscall.EPERM) && !errors.Is(err, syscall.EACCES) {
+		return err
+	}
+	switch runtime.GOOS {
+	case "linux":
+		return fmt.Errorf("%w\n  Hint: run as root, or grant capabilities:\n  sudo setcap cap_net_raw,cap_net_admin+ep /path/to/xray", err)
+	case "darwin":
+		return fmt.Errorf("%w\n  Hint: TLS spoofing requires root on macOS. Run with: sudo ./xray", err)
+	case "freebsd":
+		return fmt.Errorf("%w\n  Hint: TLS spoofing requires root on FreeBSD. Run with: sudo ./xray", err)
+	default:
+		return err
+	}
+}
diff --git a/transport/internet/tls/tlsspoof/spoof_freebsd_test.go b/transport/internet/tls/tlsspoof/spoof_freebsd_test.go
new file mode 100644
index 000000000000..a8ab2ccae823
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/spoof_freebsd_test.go
@@ -0,0 +1,82 @@
+package tlsspoof
+
+import (
+	"net"
+	"net/netip"
+	"os/user"
+	"testing"
+
+	"golang.org/x/sys/unix"
+)
+
+func TestFreeBSDTCPSequence(t *testing.T) {
+	u, err := user.Current()
+	if err == nil && u.Uid != "0" {
+		t.Skip("skipping test; must be root to use raw sockets / TCP_INFO on FreeBSD")
+	}
+
+	ln, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("Listen failed: %v", err)
+	}
+	defer ln.Close()
+
+	serverDone := make(chan struct{})
+	go func() {
+		conn, err := ln.Accept()
+		if err == nil {
+			conn.Write([]byte("hello"))
+			conn.Close()
+		}
+		close(serverDone)
+	}()
+
+	client, err := net.Dial("tcp", ln.Addr().String())
+	if err != nil {
+		t.Fatalf("Dial failed: %v", err)
+	}
+	defer client.Close()
+
+	tcpConn, ok := client.(*net.TCPConn)
+	if !ok {
+		t.Fatalf("expected *net.TCPConn, got %T", client)
+	}
+
+	sndNxt, rcvNxt, err := readFreeBSDTCPSequence(tcpConn)
+	if err != nil {
+		t.Fatalf("readFreeBSDTCPSequence failed: %v", err)
+	}
+
+	if sndNxt == 0 && rcvNxt == 0 {
+		t.Errorf("expected non-zero sequence numbers, got sndNxt=%d rcvNxt=%d", sndNxt, rcvNxt)
+	}
+	t.Logf("FreeBSD TCP sequence retrieved: snd_nxt=%d, rcv_nxt=%d", sndNxt, rcvNxt)
+	<-serverDone
+}
+
+func TestFreeBSDRawSocket(t *testing.T) {
+	u, err := user.Current()
+	if err == nil && u.Uid != "0" {
+		t.Skip("skipping test; must be root to open raw sockets")
+	}
+
+	dst := netip.MustParseAddrPort("8.8.8.8:443")
+	src := netip.MustParseAddrPort("127.0.0.1:12345")
+
+	fd, sockaddr, err := openFreeBSDRawSocket(src, dst)
+	if err != nil {
+		t.Fatalf("openFreeBSDRawSocket failed: %v", err)
+	}
+	defer func() {
+		if fd >= 0 {
+			unix.Close(fd)
+		}
+	}()
+
+	if fd < 0 {
+		t.Errorf("expected valid fd, got %d", fd)
+	}
+	if sockaddr == nil {
+		t.Error("expected valid sockaddr, got nil")
+	}
+}
diff --git a/transport/internet/tls/tlsspoof/spoof_test.go b/transport/internet/tls/tlsspoof/spoof_test.go
new file mode 100644
index 000000000000..c51e4fddceb0
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/spoof_test.go
@@ -0,0 +1,111 @@
+package tlsspoof
+
+import (
+	"testing"
+)
+
+func TestBuildFakeClientHello(t *testing.T) {
+	hello, err := buildFakeClientHello("www.example.com")
+	if err != nil {
+		t.Fatal("buildFakeClientHello returned error:", err)
+	}
+	if len(hello) == 0 {
+		t.Fatal("buildFakeClientHello returned empty payload")
+	}
+	// TLS record header: content type 0x16 (handshake)
+	if hello[0] != 0x16 {
+		t.Fatalf("expected TLS handshake record type 0x16, got 0x%02x", hello[0])
+	}
+	// TLS version: 0x0301 (TLS 1.0 record layer)
+	if hello[1] != 0x03 || hello[2] != 0x01 {
+		t.Fatalf("unexpected TLS record version: 0x%02x%02x", hello[1], hello[2])
+	}
+	t.Logf("ClientHello payload length: %d bytes", len(hello))
+}
+
+func TestBuildFakeClientHelloEmptySNI(t *testing.T) {
+	_, err := buildFakeClientHello("")
+	if err == nil {
+		t.Fatal("expected error for empty SNI")
+	}
+}
+
+func TestParseMethod(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected Method
+		hasErr   bool
+	}{
+		{"", MethodWrongSequence, false},
+		{"wrong-sequence", MethodWrongSequence, false},
+		{"wrong-checksum", MethodWrongChecksum, false},
+		{"wrong-ack", MethodWrongAcknowledgment, false},
+		{"wrong-md5", MethodWrongMD5Sig, false},
+		{"wrong-timestamp", MethodWrongTimestamp, false},
+		{"invalid", 0, true},
+	}
+	for _, tt := range tests {
+		m, err := ParseMethod(tt.input)
+		if tt.hasErr {
+			if err == nil {
+				t.Errorf("ParseMethod(%q): expected error, got nil", tt.input)
+			}
+			continue
+		}
+		if err != nil {
+			t.Errorf("ParseMethod(%q): unexpected error: %v", tt.input, err)
+			continue
+		}
+		if m != tt.expected {
+			t.Errorf("ParseMethod(%q) = %v, want %v", tt.input, m, tt.expected)
+		}
+	}
+}
+
+func TestParseOptions(t *testing.T) {
+	// Empty spoof should be a no-op
+	sni, _, err := ParseOptions("", "")
+	if err != nil {
+		t.Fatal("ParseOptions(\"\", \"\"): unexpected error:", err)
+	}
+	if sni != "" {
+		t.Fatalf("expected empty SNI, got %q", sni)
+	}
+
+	// spoof_method without spoof should error
+	_, _, err = ParseOptions("", "wrong-checksum")
+	if err == nil {
+		t.Fatal("expected error when spoof_method set without spoof")
+	}
+
+	// Valid combo
+	sni, method, err := ParseOptions("fake.example.com", "wrong-checksum")
+	if err != nil {
+		t.Fatal("ParseOptions: unexpected error:", err)
+	}
+	if sni != "fake.example.com" {
+		t.Fatalf("expected SNI 'fake.example.com', got %q", sni)
+	}
+	if method != MethodWrongChecksum {
+		t.Fatalf("expected MethodWrongChecksum, got %v", method)
+	}
+
+	// IP-literal should be rejected
+	_, _, err = ParseOptions("1.2.3.4", "wrong-checksum")
+	if err == nil {
+		t.Fatal("expected error for IP-literal spoof")
+	}
+	_, _, err = ParseOptions("::1", "wrong-checksum")
+	if err == nil {
+		t.Fatal("expected error for IP-literal spoof")
+	}
+}
+
+func TestMethodString(t *testing.T) {
+	if MethodWrongSequence.String() != "wrong-sequence" {
+		t.Fatalf("unexpected method string: %s", MethodWrongSequence.String())
+	}
+	if MethodWrongChecksum.String() != "wrong-checksum" {
+		t.Fatalf("unexpected method string: %s", MethodWrongChecksum.String())
+	}
+}
diff --git a/transport/internet/tls/tlsspoof/tcpip.go b/transport/internet/tls/tlsspoof/tcpip.go
new file mode 100644
index 000000000000..3392704c405a
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/tcpip.go
@@ -0,0 +1,155 @@
+package tlsspoof
+
+import (
+	"encoding/binary"
+	"net/netip"
+)
+
+const (
+	IPv4MinimumSize   = 20
+	IPv6MinimumSize   = 40
+	TCPMinimumSize    = 20
+	TCPProtocolNumber = 6
+
+	TCPOptionEOL      = 0
+	TCPOptionNOP      = 1
+	TCPOptionTS       = 8
+	TCPOptionTSLength = 10
+
+	TCPFlagFin = 0x01
+	TCPFlagSyn = 0x02
+	TCPFlagRst = 0x04
+	TCPFlagPsh = 0x08
+	TCPFlagAck = 0x10
+)
+
+func Checksum(data []byte, initial uint16) uint16 {
+	var csum uint32 = uint32(initial)
+	for i := 0; i < len(data)-1; i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(data[i:]))
+	}
+	if len(data)%2 == 1 {
+		csum += uint32(data[len(data)-1]) << 8
+	}
+	for csum > 0xffff {
+		csum = (csum >> 16) + (csum & 0xffff)
+	}
+	return uint16(csum)
+}
+
+func PseudoHeaderChecksum(protocol uint8, srcAddr, dstAddr []byte, totalLen uint16) uint16 {
+	var csum uint32
+	for i := 0; i < len(srcAddr); i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(srcAddr[i:]))
+	}
+	for i := 0; i < len(dstAddr); i += 2 {
+		csum += uint32(binary.BigEndian.Uint16(dstAddr[i:]))
+	}
+	csum += uint32(protocol)
+	csum += uint32(totalLen)
+	for csum > 0xffff {
+		csum = (csum >> 16) + (csum & 0xffff)
+	}
+	return uint16(csum)
+}
+
+func CombineChecksum(c1, c2 uint16) uint16 {
+	csum := uint32(c1) + uint32(c2)
+	for csum > 0xffff {
+		csum = (csum >> 16) + (csum & 0xffff)
+	}
+	return uint16(csum)
+}
+
+func EncodeTSOption(val uint32, ecr uint32, b []byte) {
+	b[0] = TCPOptionTS
+	b[1] = TCPOptionTSLength
+	binary.BigEndian.PutUint32(b[2:], val)
+	binary.BigEndian.PutUint32(b[6:], ecr)
+}
+
+func ParseTCPOptions(b []byte) (tsVal uint32, hasTS bool) {
+	for i := 0; i < len(b); {
+		if b[i] == TCPOptionEOL {
+			break
+		}
+		if b[i] == TCPOptionNOP {
+			i++
+			continue
+		}
+		if i+1 >= len(b) {
+			break
+		}
+		optLen := int(b[i+1])
+		if optLen < 2 || i+optLen > len(b) {
+			break
+		}
+		if b[i] == TCPOptionTS && optLen == TCPOptionTSLength {
+			return binary.BigEndian.Uint32(b[i+2:]), true
+		}
+		i += optLen
+	}
+	return 0, false
+}
+
+// IPv4 header representation
+type IPv4 []byte
+
+func (b IPv4) TotalLength() uint16    { return binary.BigEndian.Uint16(b[2:]) }
+func (b IPv4) Flags() uint8           { return uint8(binary.BigEndian.Uint16(b[6:]) >> 13) }
+func (b IPv4) FragmentOffset() uint16 { return binary.BigEndian.Uint16(b[6:]) & 0x1fff }
+func (b IPv4) Protocol() uint8        { return b[9] }
+func (b IPv4) HeaderLength() uint8    { return (b[0] & 0x0f) * 4 }
+
+func (b IPv4) Encode(totalLength uint16, id uint16, ttl uint8, protocol uint8, src, dst netip.Addr) {
+	b[0] = (4 << 4) | 5 // IPv4, Header Length = 20
+	b[1] = 0            // TOS
+	binary.BigEndian.PutUint16(b[2:], totalLength)
+	binary.BigEndian.PutUint16(b[4:], id)
+	binary.BigEndian.PutUint16(b[6:], 0) // Flags and Fragment Offset
+	b[8] = ttl
+	b[9] = protocol
+	b[10] = 0 // Checksum (0 for calculation)
+	copy(b[12:16], src.AsSlice())
+	copy(b[16:20], dst.AsSlice())
+	csum := Checksum(b[:20], 0)
+	binary.BigEndian.PutUint16(b[10:], ^csum)
+}
+
+type IPv6 []byte
+
+func (b IPv6) PayloadLength() uint16    { return binary.BigEndian.Uint16(b[4:]) }
+func (b IPv6) TransportProtocol() uint8 { return b[6] }
+
+func (b IPv6) Encode(payloadLength uint16, transportProtocol uint8, hopLimit uint8, src, dst netip.Addr) {
+	binary.BigEndian.PutUint32(b[0:], 6<<28) // Version 6, Traffic Class 0, Flow Label 0
+	binary.BigEndian.PutUint16(b[4:], payloadLength)
+	b[6] = transportProtocol
+	b[7] = hopLimit
+	copy(b[8:24], src.AsSlice())
+	copy(b[24:40], dst.AsSlice())
+}
+
+type TCP []byte
+
+func (b TCP) DataOffset() uint8       { return (b[12] >> 4) * 4 }
+func (b TCP) SequenceNumber() uint32  { return binary.BigEndian.Uint32(b[4:]) }
+func (b TCP) AckNumber() uint32       { return binary.BigEndian.Uint32(b[8:]) }
+func (b TCP) Options() []byte         { return b[TCPMinimumSize:b.DataOffset()] }
+func (b TCP) SetChecksum(csum uint16) { binary.BigEndian.PutUint16(b[16:], csum) }
+
+func (b TCP) Encode(srcPort, dstPort uint16, seqNum, ackNum uint32, dataOffset uint8, flags uint8, windowSize uint16) {
+	binary.BigEndian.PutUint16(b[0:], srcPort)
+	binary.BigEndian.PutUint16(b[2:], dstPort)
+	binary.BigEndian.PutUint32(b[4:], seqNum)
+	binary.BigEndian.PutUint32(b[8:], ackNum)
+	b[12] = (dataOffset / 4) << 4
+	b[13] = flags
+	binary.BigEndian.PutUint16(b[14:], windowSize)
+	b[16] = 0                             // Checksum
+	binary.BigEndian.PutUint16(b[18:], 0) // Urgent pointer
+}
+
+func (b TCP) CalculateChecksum(initial uint16) uint16 {
+	return Checksum(b, initial)
+}
diff --git a/transport/internet/tls/tlsspoof/windivert/assets/LICENSE.txt b/transport/internet/tls/tlsspoof/windivert/assets/LICENSE.txt
new file mode 100644
index 000000000000..8489a8e773c3
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/windivert/assets/LICENSE.txt
@@ -0,0 +1,1191 @@
+WinDivert is dual-licensed under your choice of the GNU Lesser General Public
+License (LGPL) Version 3 or the GNU General Public License (GPL) Version 2.
+Copies of the LGPLv3, GPLv3 and GPLv2 are provided below.
+
+==============================================================================
+
+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+  A "Combined Work" is a work produced by combining or linking an
+Application with the Library.  The particular version of the Library
+with which the Combined Work was made is also called the "Linked
+Version".
+
+  The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+  The "Corresponding Application Code" for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+  2. Conveying Modified Versions.
+
+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+   a) under this License, provided that you make a good faith effort to
+   ensure that, in the event an Application does not supply the
+   function or data, the facility still operates, and performs
+   whatever part of its purpose remains meaningful, or
+
+   b) under the GNU GPL, with none of the additional permissions of
+   this License applicable to that copy.
+
+  3. Object Code Incorporating Material from Library Header Files.
+
+  The object code form of an Application may incorporate material from
+a header file that is part of the Library.  You may convey such object
+code under terms of your choice, provided that, if the incorporated
+material is not limited to numerical parameters, data structure
+layouts and accessors, or small macros, inline functions and templates
+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the object code with a copy of the GNU GPL and this license
+   document.
+
+  4. Combined Works.
+
+  You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+   a) Give prominent notice with each copy of the Combined Work that
+   the Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the Combined Work with a copy of the GNU GPL and this license
+   document.
+
+   c) For a Combined Work that displays copyright notices during
+   execution, include the copyright notice for the Library among
+   these notices, as well as a reference directing the user to the
+   copies of the GNU GPL and this license document.
+
+   d) Do one of the following:
+
+       0) Convey the Minimal Corresponding Source under the terms of this
+       License, and the Corresponding Application Code in a form
+       suitable for, and under terms that permit, the user to
+       recombine or relink the Application with a modified version of
+       the Linked Version to produce a modified Combined Work, in the
+       manner specified by section 6 of the GNU GPL for conveying
+       Corresponding Source.
+
+       1) Use a suitable shared library mechanism for linking with the
+       Library.  A suitable mechanism is one that (a) uses at run time
+       a copy of the Library already present on the user's computer
+       system, and (b) will operate properly with a modified version
+       of the Library that is interface-compatible with the Linked
+       Version.
+
+   e) Provide Installation Information, but only if you would otherwise
+   be required to provide such information under section 6 of the
+   GNU GPL, and only to the extent that such information is
+   necessary to install and execute a modified version of the
+   Combined Work produced by recombining or relinking the
+   Application with a modified version of the Linked Version. (If
+   you use option 4d0, the Installation Information must accompany
+   the Minimal Corresponding Source and Corresponding Application
+   Code. If you use option 4d1, you must provide the Installation
+   Information in the manner specified by section 6 of the GNU GPL
+   for conveying Corresponding Source.)
+
+  5. Combined Libraries.
+
+  You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+   a) Accompany the combined library with a copy of the same work based
+   on the Library, uncombined with any other library facilities,
+   conveyed under the terms of this License.
+
+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
+
+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.
+
+==============================================================================
+
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.  We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors.  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights.  Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received.  You must make sure that they, too, receive
+or can get the source code.  And you must show them these terms so they
+know their rights.
+
+  Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+  For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software.  For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+  Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so.  This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software.  The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable.  Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products.  If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+  Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary.  To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
+
+  0. Definitions.
+
+  "This License" refers to version 3 of the GNU General Public License.
+
+  "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+  "The Program" refers to any copyrightable work licensed under this
+License.  Each licensee is addressed as "you".  "Licensees" and
+"recipients" may be individuals or organizations.
+
+  To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy.  The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+  A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+  To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy.  Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+  To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies.  Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+  An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License.  If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+  1. Source Code.
+
+  The "source code" for a work means the preferred form of the work
+for making modifications to it.  "Object code" means any non-source
+form of a work.
+
+  A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+  The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form.  A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+  The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities.  However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work.  For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+  The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+  The Corresponding Source for a work in source code form is that
+same work.
+
+  2. Basic Permissions.
+
+  All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met.  This License explicitly affirms your unlimited
+permission to run the unmodified Program.  The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work.  This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+  You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force.  You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright.  Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+  Conveying under any other circumstances is permitted solely under
+the conditions stated below.  Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+  3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+  No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+  When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+  4. Conveying Verbatim Copies.
+
+  You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+  You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+  5. Conveying Modified Source Versions.
+
+  You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+    a) The work must carry prominent notices stating that you modified
+    it, and giving a relevant date.
+
+    b) The work must carry prominent notices stating that it is
+    released under this License and any conditions added under section
+    7.  This requirement modifies the requirement in section 4 to
+    "keep intact all notices".
+
+    c) You must license the entire work, as a whole, under this
+    License to anyone who comes into possession of a copy.  This
+    License will therefore apply, along with any applicable section 7
+    additional terms, to the whole of the work, and all its parts,
+    regardless of how they are packaged.  This License gives no
+    permission to license the work in any other way, but it does not
+    invalidate such permission if you have separately received it.
+
+    d) If the work has interactive user interfaces, each must display
+    Appropriate Legal Notices; however, if the Program has interactive
+    interfaces that do not display Appropriate Legal Notices, your
+    work need not make them do so.
+
+  A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+"aggregate" if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit.  Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+  6. Conveying Non-Source Forms.
+
+  You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:
+
+    a) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by the
+    Corresponding Source fixed on a durable physical medium
+    customarily used for software interchange.
+
+    b) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by a
+    written offer, valid for at least three years and valid for as
+    long as you offer spare parts or customer support for that product
+    model, to give anyone who possesses the object code either (1) a
+    copy of the Corresponding Source for all the software in the
+    product that is covered by this License, on a durable physical
+    medium customarily used for software interchange, for a price no
+    more than your reasonable cost of physically performing this
+    conveying of source, or (2) access to copy the
+    Corresponding Source from a network server at no charge.
+
+    c) Convey individual copies of the object code with a copy of the
+    written offer to provide the Corresponding Source.  This
+    alternative is allowed only occasionally and noncommercially, and
+    only if you received the object code with such an offer, in accord
+    with subsection 6b.
+
+    d) Convey the object code by offering access from a designated
+    place (gratis or for a charge), and offer equivalent access to the
+    Corresponding Source in the same way through the same place at no
+    further charge.  You need not require recipients to copy the
+    Corresponding Source along with the object code.  If the place to
+    copy the object code is a network server, the Corresponding Source
+    may be on a different server (operated by you or a third party)
+    that supports equivalent copying facilities, provided you maintain
+    clear directions next to the object code saying where to find the
+    Corresponding Source.  Regardless of what server hosts the
+    Corresponding Source, you remain obligated to ensure that it is
+    available for as long as needed to satisfy these requirements.
+
+    e) Convey the object code using peer-to-peer transmission, provided
+    you inform other peers where the object code and Corresponding
+    Source of the work are being offered to the general public at no
+    charge under subsection 6d.
+
+  A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+  A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling.  In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage.  For a particular
+product received by a particular user, "normally used" refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product.  A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.
+
+  "Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source.  The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.
+
+  If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information.  But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+  The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed.  Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.
+
+  Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+  7. Additional Terms.
+
+  "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law.  If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+  When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it.  (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.)  You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+  Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:
+
+    a) Disclaiming warranty or limiting liability differently from the
+    terms of sections 15 and 16 of this License; or
+
+    b) Requiring preservation of specified reasonable legal notices or
+    author attributions in that material or in the Appropriate Legal
+    Notices displayed by works containing it; or
+
+    c) Prohibiting misrepresentation of the origin of that material, or
+    requiring that modified versions of such material be marked in
+    reasonable ways as different from the original version; or
+
+    d) Limiting the use for publicity purposes of names of licensors or
+    authors of the material; or
+
+    e) Declining to grant rights under trademark law for use of some
+    trade names, trademarks, or service marks; or
+
+    f) Requiring indemnification of licensors and authors of that
+    material by anyone who conveys the material (or modified versions of
+    it) with contractual assumptions of liability to the recipient, for
+    any liability that these contractual assumptions directly impose on
+    those licensors and authors.
+
+  All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10.  If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term.  If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+  If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+  Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+  8. Termination.
+
+  You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+  However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+  Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+  Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+  9. Acceptance Not Required for Having Copies.
+
+  You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+  10. Automatic Licensing of Downstream Recipients.
+
+  Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.
+
+  An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+  You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+  11. Patents.
+
+  A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's "contributor version".
+
+  A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+  Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+  In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+  If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+  If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+  A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
+
+==============================================================================
+
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.
+
diff --git a/transport/internet/tls/tlsspoof/windivert/assets/WinDivert32.sys b/transport/internet/tls/tlsspoof/windivert/assets/WinDivert32.sys
new file mode 100644
index 000000000000..d06738cbb783
Binary files /dev/null and b/transport/internet/tls/tlsspoof/windivert/assets/WinDivert32.sys differ
diff --git a/transport/internet/tls/tlsspoof/windivert/assets/WinDivert64.sys b/transport/internet/tls/tlsspoof/windivert/assets/WinDivert64.sys
new file mode 100644
index 000000000000..218ccaf423ef
Binary files /dev/null and b/transport/internet/tls/tlsspoof/windivert/assets/WinDivert64.sys differ
diff --git a/transport/internet/tls/tlsspoof/windivert/assets_386.go b/transport/internet/tls/tlsspoof/windivert/assets_386.go
new file mode 100644
index 000000000000..0cbf35ed5cbf
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/windivert/assets_386.go
@@ -0,0 +1,14 @@
+//go:build windows && 386
+
+package windivert
+
+import _ "embed"
+
+//go:embed assets/WinDivert32.sys
+var sysBytes []byte
+
+func assetFiles() []assetFile {
+	return []assetFile{{"WinDivert32.sys", sysBytes}}
+}
+
+func driverSysName() string { return "WinDivert32.sys" }
diff --git a/transport/internet/tls/tlsspoof/windivert/assets_amd64.go b/transport/internet/tls/tlsspoof/windivert/assets_amd64.go
new file mode 100644
index 000000000000..2c9fb6c6ad19
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/windivert/assets_amd64.go
@@ -0,0 +1,14 @@
+//go:build windows && amd64
+
+package windivert
+
+import _ "embed"
+
+//go:embed assets/WinDivert64.sys
+var sysBytes []byte
+
+func assetFiles() []assetFile {
+	return []assetFile{{"WinDivert64.sys", sysBytes}}
+}
+
+func driverSysName() string { return "WinDivert64.sys" }
diff --git a/transport/internet/tls/tlsspoof/windivert/assets_unsupported.go b/transport/internet/tls/tlsspoof/windivert/assets_unsupported.go
new file mode 100644
index 000000000000..04698953fa6b
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/windivert/assets_unsupported.go
@@ -0,0 +1,7 @@
+//go:build windows && !amd64 && !386
+
+package windivert
+
+func assetFiles() []assetFile { return nil }
+
+func driverSysName() string { return "" }
diff --git a/transport/internet/tls/tlsspoof/windivert/driver_windows.go b/transport/internet/tls/tlsspoof/windivert/driver_windows.go
new file mode 100644
index 000000000000..50e94c578422
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/windivert/driver_windows.go
@@ -0,0 +1,211 @@
+//go:build windows
+
+package windivert
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strconv"
+	"sync"
+
+	"golang.org/x/sys/windows"
+)
+
+const (
+	driverServiceName = "WinDivert"
+	driverDeviceName  = `\\.\WinDivert`
+)
+
+var (
+	driverOnce sync.Once
+	driverErr  error
+	// driverDevName is ASCII-safe and must be available before ensureDriver
+	// so Open can try CreateFile first and only install on FILE_NOT_FOUND.
+	driverDevName, _ = windows.UTF16PtrFromString(driverDeviceName)
+)
+
+// Requires SeLoadDriverPrivilege (Administrator). Running the 386 build
+// under WOW64 on a 64-bit kernel is rejected — use the amd64 build.
+func ensureDriver() error {
+	driverOnce.Do(func() {
+		driverErr = installDriver()
+	})
+	return driverErr
+}
+
+func installDriver() error {
+	if runtime.GOARCH == "386" {
+		var isWow64 bool
+		err := windows.IsWow64Process(windows.CurrentProcess(), &isWow64)
+		if err == nil && isWow64 {
+			return errors.New("windivert: 386 build detected running under WOW64 on a 64-bit kernel; use the amd64 build")
+		}
+	}
+
+	dir, err := ensureExtracted()
+	if err != nil {
+		return err
+	}
+	sysPath := filepath.Join(dir, driverSysName())
+	sysPathW, err := windows.UTF16PtrFromString(sysPath)
+	if err != nil {
+		return fmt.Errorf("windivert: utf16 driver path: %w", err)
+	}
+
+	// Serialize driver install across concurrent processes.
+	mutexName, _ := windows.UTF16PtrFromString("WinDivertDriverInstallMutex")
+	mutex, err := windows.CreateMutex(nil, false, mutexName)
+	if err != nil {
+		return fmt.Errorf("windivert: create install mutex: %w", err)
+	}
+	defer windows.CloseHandle(mutex)
+	_, err = windows.WaitForSingleObject(mutex, windows.INFINITE)
+	if err != nil {
+		return fmt.Errorf("windivert: wait install mutex: %w", err)
+	}
+	defer windows.ReleaseMutex(mutex)
+
+	manager, err := windows.OpenSCManager(nil, nil, windows.SC_MANAGER_ALL_ACCESS)
+	if err != nil {
+		return fmt.Errorf("windivert: open SCM: %w", err)
+	}
+	defer windows.CloseServiceHandle(manager)
+
+	serviceNameW, _ := windows.UTF16PtrFromString(driverServiceName)
+	service, err := windows.OpenService(manager, serviceNameW, windows.SERVICE_ALL_ACCESS)
+	if err != nil {
+		service, err = windows.CreateService(
+			manager,
+			serviceNameW,
+			serviceNameW,
+			windows.SERVICE_ALL_ACCESS,
+			windows.SERVICE_KERNEL_DRIVER,
+			windows.SERVICE_DEMAND_START,
+			windows.SERVICE_ERROR_NORMAL,
+			sysPathW,
+			nil, nil, nil, nil, nil,
+		)
+		if err != nil {
+			if errors.Is(err, windows.ERROR_SERVICE_EXISTS) {
+				service, err = windows.OpenService(manager, serviceNameW, windows.SERVICE_ALL_ACCESS)
+			}
+			if err != nil {
+				return wrapDriverInstallError(err)
+			}
+		}
+	}
+	defer windows.CloseServiceHandle(service)
+
+	err = windows.StartService(service, 0, nil)
+	if err != nil && errors.Is(err, windows.ERROR_SERVICE_DISABLED) {
+		// A prior process called DeleteService on a still-running kernel
+		// driver: SCM marks the record for deletion and flips START_TYPE
+		// to DISABLED until the last handle closes. Re-enable so we can
+		// start it instead of waiting for a reboot.
+		err = windows.ChangeServiceConfig(
+			service,
+			windows.SERVICE_NO_CHANGE,
+			windows.SERVICE_DEMAND_START,
+			windows.SERVICE_NO_CHANGE,
+			nil, nil, nil, nil, nil, nil, nil,
+		)
+		if err != nil {
+			return fmt.Errorf("windivert: re-enable disabled service: %w", err)
+		}
+		err = windows.StartService(service, 0, nil)
+	}
+	if err == nil {
+		// Mark for deletion so the driver unregisters when the last handle
+		// closes or on next reboot. Matches the upstream DLL's behavior:
+		// only the process that actually started the service takes on the
+		// cleanup responsibility. If another process already started it,
+		// we leave DeleteService to them.
+		_ = windows.DeleteService(service)
+	} else if !errors.Is(err, windows.ERROR_SERVICE_ALREADY_RUNNING) {
+		return fmt.Errorf("windivert: start service: %w", err)
+	}
+	return nil
+}
+
+func wrapDriverInstallError(err error) error {
+	if errors.Is(err, windows.ERROR_ACCESS_DENIED) {
+		return fmt.Errorf("windivert: installing the kernel driver requires Administrator privileges: %w", err)
+	}
+	return fmt.Errorf("windivert: create service: %w", err)
+}
+
+type assetFile struct {
+	name string
+	data []byte
+}
+
+var (
+	extractOnce sync.Once
+	extractErr  error
+	extractDir  string
+)
+
+// The on-disk copy is protected by Windows Authenticode signature
+// enforcement, which rejects any tampered .sys at StartService time.
+func ensureExtracted() (string, error) {
+	extractOnce.Do(func() {
+		extractDir, extractErr = extractImpl()
+	})
+	return extractDir, extractErr
+}
+
+func extractImpl() (string, error) {
+	files := assetFiles()
+	if len(files) == 0 {
+		return "", fmt.Errorf("windivert: unsupported architecture %s", runtime.GOARCH)
+	}
+
+	base, err := os.UserCacheDir()
+	if err != nil {
+		return "", fmt.Errorf("windivert: locate user cache dir: %w", err)
+	}
+	dir := filepath.Join(base, "xray-core", "windivert", "v"+AssetVersion)
+	err = os.MkdirAll(dir, 0o755)
+	if err != nil {
+		return "", fmt.Errorf("windivert: mkdir %s: %w", dir, err)
+	}
+
+	for _, asset := range files {
+		err = ensureAsset(dir, asset)
+		if err != nil {
+			return "", err
+		}
+	}
+	return dir, nil
+}
+
+// Concurrent sing-box processes race on os.Rename (atomic on NTFS);
+// whichever wins creates the final file. Writers that lose the race
+// silently discard their temp copy.
+func ensureAsset(dir string, asset assetFile) error {
+	target := filepath.Join(dir, asset.name)
+	_, err := os.Stat(target)
+	if err == nil {
+		return nil
+	}
+	if !os.IsNotExist(err) {
+		return fmt.Errorf("windivert: stat %s: %w", asset.name, err)
+	}
+	tmp := target + ".tmp-" + strconv.Itoa(os.Getpid())
+	err = os.WriteFile(tmp, asset.data, 0o644)
+	if err != nil {
+		return fmt.Errorf("windivert: write %s: %w", asset.name, err)
+	}
+	err = os.Rename(tmp, target)
+	if err != nil {
+		os.Remove(tmp)
+		if _, statErr := os.Stat(target); statErr == nil {
+			return nil
+		}
+		return fmt.Errorf("windivert: rename %s: %w", asset.name, err)
+	}
+	return nil
+}
diff --git a/transport/internet/tls/tlsspoof/windivert/filter.go b/transport/internet/tls/tlsspoof/windivert/filter.go
new file mode 100644
index 000000000000..d63adae2b630
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/windivert/filter.go
@@ -0,0 +1,181 @@
+package windivert
+
+import (
+	"encoding/binary"
+	"errors"
+	"net/netip"
+)
+
+// WINDIVERT_FILTER VM instruction layout (24 bytes, #pragma pack(1)):
+//
+//	word 0 (LE):  field:11 | test:5 | success:16
+//	word 1 (LE):  failure:16 | neg:1 | reserved:15
+//	words 2..5:   arg[4] (native-endian uint32 each)
+//
+// The driver walks this as a decision tree: evaluate the test at inst i;
+// on success jump to success; on failure jump to failure. Continuations
+// 0x7FFE and 0x7FFF are ACCEPT and REJECT terminals.
+const (
+	filterInstBytes = 24
+	filterMaxInsts  = 256
+
+	fieldZero        = 0
+	fieldOutbound    = 2
+	fieldIP          = 5
+	fieldIPv6        = 6
+	fieldTCP         = 8
+	fieldIPSrcAddr   = 21
+	fieldIPDstAddr   = 22
+	fieldIPv6SrcAddr = 28
+	fieldIPv6DstAddr = 29
+	fieldTCPSrcPort  = 38
+	fieldTCPDstPort  = 39
+
+	testEQ = 0
+
+	resultAccept uint16 = 0x7FFE
+	resultReject uint16 = 0x7FFF
+)
+
+// Filter flags passed to IOCTL_WINDIVERT_STARTUP alongside the compiled
+// filter. These tell the driver what *kinds* of packets the filter might
+// match, used as a kernel-side fast-reject.
+const (
+	filterFlagOutbound uint64 = 0x0020
+	filterFlagIP       uint64 = 0x0040
+	filterFlagIPv6     uint64 = 0x0080
+)
+
+type filterInst struct {
+	field   uint16 // 11 bits used
+	test    uint8  //  5 bits used
+	success uint16
+	failure uint16
+	neg     bool
+	arg     [4]uint32
+}
+
+// Filter is a typed specification of packets to capture. It replaces
+// WinDivert's filter string language.
+//
+// Zero value = "reject all" (match nothing), suitable for send-only handles.
+type Filter struct {
+	insts []filterInst
+	flags uint64 // filter flags for STARTUP ioctl
+}
+
+// reject returns a filter that matches no packet. The empty insts slice
+// is encoded as a single rejecting instruction by encode().
+func reject() *Filter {
+	return &Filter{}
+}
+
+// OutboundTCP returns a filter matching outbound TCP packets on the given
+// 5-tuple. Both addresses must share an address family (IPv4 or IPv6).
+func OutboundTCP(src, dst netip.AddrPort) (*Filter, error) {
+	if !src.IsValid() || !dst.IsValid() {
+		return nil, errors.New("windivert: filter: invalid address port")
+	}
+	if src.Addr().Is4() != dst.Addr().Is4() {
+		return nil, errors.New("windivert: filter: mixed IPv4/IPv6")
+	}
+	f := &Filter{
+		flags: filterFlagOutbound,
+	}
+	// Insts chain as AND: each test's failure = REJECT, success = next inst.
+	// The final inst's success = ACCEPT.
+	f.add(fieldOutbound, testEQ, argUint32(1))
+	if src.Addr().Is4() {
+		f.flags |= filterFlagIP
+		f.add(fieldIP, testEQ, argUint32(1))
+		f.add(fieldTCP, testEQ, argUint32(1))
+		f.add(fieldIPSrcAddr, testEQ, argIPv4(src.Addr()))
+		f.add(fieldIPDstAddr, testEQ, argIPv4(dst.Addr()))
+	} else {
+		f.flags |= filterFlagIPv6
+		f.add(fieldIPv6, testEQ, argUint32(1))
+		f.add(fieldTCP, testEQ, argUint32(1))
+		f.add(fieldIPv6SrcAddr, testEQ, argIPv6(src.Addr()))
+		f.add(fieldIPv6DstAddr, testEQ, argIPv6(dst.Addr()))
+	}
+	f.add(fieldTCPSrcPort, testEQ, argUint32(uint32(src.Port())))
+	f.add(fieldTCPDstPort, testEQ, argUint32(uint32(dst.Port())))
+	return f, nil
+}
+
+func (f *Filter) add(field uint16, test uint8, arg [4]uint32) {
+	f.insts = append(f.insts, filterInst{field: field, test: test, arg: arg})
+}
+
+func argUint32(v uint32) [4]uint32 { return [4]uint32{v, 0, 0, 0} }
+
+// argIPv4 encodes an IPv4 address for IP_SRCADDR/IP_DSTADDR. The driver
+// compares against an IPv4-mapped-IPv6 form: {host_order_u32, 0x0000FFFF,
+// 0, 0} (see sys/windivert.c windivert_get_ipv4_addr and the IPv4_SRCADDR
+// val-word construction). Omitting the 0x0000FFFF marker causes the EQ
+// test to fail for every packet.
+func argIPv4(addr netip.Addr) [4]uint32 {
+	b := addr.As4()
+	return [4]uint32{binary.BigEndian.Uint32(b[:]), 0x0000FFFF, 0, 0}
+}
+
+// argIPv6 encodes an IPv6 address for IPV6_SRCADDR/IPV6_DSTADDR. The
+// driver stores the address as four host-order uint32s in REVERSED word
+// order: val[0]=low (bytes 12..15), val[3]=high (bytes 0..3). See
+// sys/windivert.c windivert_outbound_network_v6_classify val-word
+// construction.
+func argIPv6(addr netip.Addr) [4]uint32 {
+	b := addr.As16()
+	return [4]uint32{
+		binary.BigEndian.Uint32(b[12:16]),
+		binary.BigEndian.Uint32(b[8:12]),
+		binary.BigEndian.Uint32(b[4:8]),
+		binary.BigEndian.Uint32(b[0:4]),
+	}
+}
+
+// encode serializes the Filter to the on-wire WINDIVERT_FILTER[] format
+// plus the filter_flags for STARTUP ioctl.
+func (f *Filter) encode() ([]byte, uint64, error) {
+	if len(f.insts) == 0 {
+		// "Reject all" — one instruction, ZERO == 0 is always true, but we
+		// invert by setting both success and failure to REJECT.
+		return encodeInst(filterInst{
+			field:   fieldZero,
+			test:    testEQ,
+			success: resultReject,
+			failure: resultReject,
+		}), 0, nil
+	}
+	if len(f.insts) > filterMaxInsts-1 {
+		return nil, 0, errors.New("windivert: filter too long")
+	}
+	buf := make([]byte, 0, filterInstBytes*len(f.insts))
+	for i, inst := range f.insts {
+		if i == len(f.insts)-1 {
+			inst.success = resultAccept
+		} else {
+			inst.success = uint16(i + 1)
+		}
+		inst.failure = resultReject
+		buf = append(buf, encodeInst(inst)...)
+	}
+	return buf, f.flags, nil
+}
+
+func encodeInst(inst filterInst) []byte {
+	out := make([]byte, filterInstBytes)
+	word0 := uint32(inst.field&0x7FF) | uint32(inst.test&0x1F)<<11 |
+		uint32(inst.success)<<16
+	word1 := uint32(inst.failure)
+	if inst.neg {
+		word1 |= 1 << 16
+	}
+	binary.LittleEndian.PutUint32(out[0:4], word0)
+	binary.LittleEndian.PutUint32(out[4:8], word1)
+	binary.LittleEndian.PutUint32(out[8:12], inst.arg[0])
+	binary.LittleEndian.PutUint32(out[12:16], inst.arg[1])
+	binary.LittleEndian.PutUint32(out[16:20], inst.arg[2])
+	binary.LittleEndian.PutUint32(out[20:24], inst.arg[3])
+	return out
+}
diff --git a/transport/internet/tls/tlsspoof/windivert/handle_windows.go b/transport/internet/tls/tlsspoof/windivert/handle_windows.go
new file mode 100644
index 000000000000..c48e6214c11b
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/windivert/handle_windows.go
@@ -0,0 +1,323 @@
+//go:build windows
+
+package windivert
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"runtime"
+	"sync"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+// Handle owns a WinDivert kernel device handle plus a private event for
+// overlapped I/O. Methods on *Handle are not safe for concurrent use
+// across goroutines (there is a single shared event per Handle).
+//
+// addr is a per-Handle Address buffer the IOCTL struct embeds a pointer
+// to. It lives on the heap (as a field of a heap-allocated Handle) so
+// the pointer value stored as bytes in the ioctl buffer remains valid
+// across stack growth between buildIoctl* and the DeviceIoControl
+// syscall — stack-local Address values are not safe for this pattern
+// because Go's escape analysis does not see the pointer through the
+// unsafe.Pointer → uintptr → bytes conversion.
+type Handle struct {
+	device   windows.Handle
+	event    windows.Handle
+	closing  sync.Once
+	closeErr error
+	addr     Address
+}
+
+// Filter may be nil for "reject all", suitable for send-only handles.
+// Requires Administrator on first call per process (installs the kernel
+// driver via SCM); subsequent calls reuse the running driver.
+func Open(filter *Filter, layer Layer, priority int16, flags Flag) (*Handle, error) {
+	err := validateOpenArgs(layer, priority, flags)
+	if err != nil {
+		return nil, err
+	}
+	if filter == nil {
+		filter = reject()
+	}
+	filterBin, filterFlags, err := filter.encode()
+	if err != nil {
+		return nil, err
+	}
+	device, err := openDevice()
+	if err != nil {
+		if !errors.Is(err, windows.ERROR_FILE_NOT_FOUND) &&
+			!errors.Is(err, windows.ERROR_PATH_NOT_FOUND) {
+			if errors.Is(err, windows.ERROR_ACCESS_DENIED) {
+				return nil, fmt.Errorf("windivert: open device (administrator required): %w", err)
+			}
+			return nil, fmt.Errorf("windivert: open device: %w", err)
+		}
+		// Device node missing: kernel driver not loaded. Install + retry.
+		// Matches WinDivertOpen's lazy-install path; avoids racing StartService
+		// against a still-loaded driver whose SCM record is marked for deletion.
+		err = ensureDriver()
+		if err != nil {
+			return nil, err
+		}
+		device, err = openDevice()
+		if err != nil {
+			if errors.Is(err, windows.ERROR_ACCESS_DENIED) {
+				return nil, fmt.Errorf("windivert: open device (administrator required): %w", err)
+			}
+			return nil, fmt.Errorf("windivert: open device: %w", err)
+		}
+	}
+	event, err := windows.CreateEvent(nil, 1, 0, nil) // manual reset, unsignaled
+	if err != nil {
+		windows.CloseHandle(device)
+		return nil, fmt.Errorf("windivert: create event: %w", err)
+	}
+	h := &Handle{device: device, event: event}
+
+	err = h.initialize(layer, priority, flags)
+	if err != nil {
+		h.Close()
+		return nil, err
+	}
+	err = h.startup(filterBin, filterFlags)
+	if err != nil {
+		h.Close()
+		return nil, err
+	}
+	return h, nil
+}
+
+func openDevice() (windows.Handle, error) {
+	return windows.CreateFile(
+		driverDevName,
+		windows.GENERIC_READ|windows.GENERIC_WRITE,
+		0, nil,
+		windows.OPEN_EXISTING,
+		windows.FILE_ATTRIBUTE_NORMAL|windows.FILE_FLAG_OVERLAPPED,
+		0,
+	)
+}
+
+func validateOpenArgs(layer Layer, priority int16, flags Flag) error {
+	if layer != LayerNetwork {
+		return fmt.Errorf("windivert: invalid layer %d", uint32(layer))
+	}
+	if priority < PriorityLowest || priority > PriorityHighest {
+		return errors.New("windivert: priority out of range")
+	}
+	const supportedFlags = FlagSniff | FlagSendOnly
+	if flags&^supportedFlags != 0 {
+		return errors.New("windivert: unknown flag bits")
+	}
+	if flags&FlagSniff != 0 && flags&FlagSendOnly != 0 {
+		return errors.New("windivert: FlagSniff and FlagSendOnly are mutually exclusive")
+	}
+	return nil
+}
+
+func (h *Handle) initialize(layer Layer, priority int16, flags Flag) error {
+	in := buildIoctlInitialize(layer, priority, flags)
+	// WINDIVERT_VERSION is a 64-byte packed struct; only the first 20
+	// bytes (magic, major, minor, bits) carry data, the rest is reserved.
+	var outBuf [versionStructSize]byte
+	binary.LittleEndian.PutUint64(outBuf[0:8], magicDLL)
+	binary.LittleEndian.PutUint32(outBuf[8:12], versionMajor)
+	binary.LittleEndian.PutUint32(outBuf[12:16], versionMinor)
+	binary.LittleEndian.PutUint32(outBuf[16:20], uint32(unsafe.Sizeof(uintptr(0))*8))
+	_, err := doIoctl(h.device, ioctlInitialize, in[:], outBuf[:], h.event)
+	if err != nil {
+		return fmt.Errorf("windivert: initialize ioctl: %w", err)
+	}
+	gotMagic := binary.LittleEndian.Uint64(outBuf[0:8])
+	if gotMagic != magicSYS {
+		return fmt.Errorf("windivert: driver magic mismatch (got %d)", gotMagic)
+	}
+	gotMajor := binary.LittleEndian.Uint32(outBuf[8:12])
+	if gotMajor < versionMajor {
+		gotMinor := binary.LittleEndian.Uint32(outBuf[12:16])
+		return fmt.Errorf("windivert: driver version too old: %d.%d", gotMajor, gotMinor)
+	}
+	return nil
+}
+
+func (h *Handle) startup(filterBin []byte, filterFlags uint64) error {
+	in := buildIoctlStartup(filterFlags)
+	_, err := doIoctl(h.device, ioctlStartup, in[:], filterBin, h.event)
+	if err != nil {
+		return fmt.Errorf("windivert: startup ioctl: %w", err)
+	}
+	return nil
+}
+
+// If the handle is closed mid-Recv the error wraps ERROR_OPERATION_ABORTED.
+func (h *Handle) Recv(buf []byte) (int, Address, error) {
+	if len(buf) == 0 {
+		return 0, Address{}, errors.New("windivert: recv: zero-length buffer")
+	}
+	h.addr = Address{}
+	in := buildIoctlRecv(&h.addr)
+	n, err := doIoctl(h.device, ioctlRecv, in[:], buf, h.event)
+	runtime.KeepAlive(h)
+	if err != nil {
+		return 0, Address{}, err
+	}
+	return int(n), h.addr, nil
+}
+
+// The address's Outbound flag controls whether the packet is sent toward
+// the wire (outbound=true) or delivered up the stack (outbound=false).
+// IfIdx and SubIfIdx can stay zero — the driver uses the routing table
+// when IfIdx=0.
+func (h *Handle) Send(packet []byte, addr *Address) (int, error) {
+	if len(packet) == 0 {
+		return 0, errors.New("windivert: send: empty packet")
+	}
+	if addr == nil {
+		return 0, errors.New("windivert: send: nil address")
+	}
+	h.addr = *addr
+	in := buildIoctlSend(&h.addr)
+	n, err := doIoctl(h.device, ioctlSend, in[:], packet, h.event)
+	runtime.KeepAlive(h)
+	if err != nil {
+		return 0, err
+	}
+	return int(n), nil
+}
+
+// Idempotent. Aborts any in-flight I/O on the handle.
+func (h *Handle) Close() error {
+	h.closing.Do(func() {
+		var errs []error
+		if h.device != 0 {
+			err := windows.CloseHandle(h.device)
+			if err != nil {
+				errs = append(errs, err)
+			}
+			h.device = 0
+		}
+		if h.event != 0 {
+			err := windows.CloseHandle(h.event)
+			if err != nil {
+				errs = append(errs, err)
+			}
+			h.event = 0
+		}
+		h.closeErr = errors.Join(errs...)
+	})
+	return h.closeErr
+}
+
+// IOCTL codes from windivert_device.h. CTL_CODE macro layout:
+//
+//	(DeviceType << 16) | (Access << 14) | (Function << 2) | Method
+const (
+	fileDeviceNetwork uint32 = 0x12
+	accessReadWrite   uint32 = 3 // FILE_READ_DATA | FILE_WRITE_DATA
+	accessRead        uint32 = 1
+
+	methodInDirect  uint32 = 1
+	methodOutDirect uint32 = 2
+)
+
+func ctlCode(deviceType, access, function, method uint32) uint32 {
+	return (deviceType << 16) | (access << 14) | (function << 2) | method
+}
+
+var (
+	ioctlInitialize = ctlCode(fileDeviceNetwork, accessReadWrite, 0x921, methodOutDirect)
+	ioctlStartup    = ctlCode(fileDeviceNetwork, accessReadWrite, 0x922, methodInDirect)
+	ioctlRecv       = ctlCode(fileDeviceNetwork, accessRead, 0x923, methodOutDirect)
+	ioctlSend       = ctlCode(fileDeviceNetwork, accessReadWrite, 0x924, methodInDirect)
+)
+
+// Magic numbers exchanged during INITIALIZE. DLL sends magicDLL in the
+// version struct; driver returns magicSYS on success.
+const (
+	magicDLL uint64 = 0x4C4C447669645724 // "$WdivDLL" in LE bytes
+	magicSYS uint64 = 0x5359537669645723 // "#WdivSYS" in LE bytes
+)
+
+const (
+	versionMajor uint32 = 2
+	versionMinor uint32 = 2
+)
+
+// Size of the WINDIVERT_IOCTL union on wire (packed).
+const ioctlSize = 16
+
+// Size of WINDIVERT_VERSION on wire (packed). Only the first 20 bytes
+// carry data; the rest is reserved zero padding.
+const versionStructSize = 64
+
+// doIoctl performs a single synchronous (blocking) overlapped
+// DeviceIoControl. The handle is opened with FILE_FLAG_OVERLAPPED so
+// DeviceIoControl returns ERROR_IO_PENDING; we then wait for completion
+// via GetOverlappedResult. Event is passed in so callers can reuse it
+// across calls on the same handle (avoids per-call CreateEvent).
+func doIoctl(handle windows.Handle, code uint32, in []byte, out []byte, event windows.Handle) (uint32, error) {
+	var overlapped windows.Overlapped
+	overlapped.HEvent = event
+	_ = windows.ResetEvent(event)
+
+	var inPtr *byte
+	var inLen uint32
+	if len(in) > 0 {
+		inPtr = &in[0]
+		inLen = uint32(len(in))
+	}
+	var outPtr *byte
+	var outLen uint32
+	if len(out) > 0 {
+		outPtr = &out[0]
+		outLen = uint32(len(out))
+	}
+	var returned uint32
+	err := windows.DeviceIoControl(handle, code, inPtr, inLen, outPtr, outLen, &returned, &overlapped)
+	if err != nil && !errors.Is(err, windows.ERROR_IO_PENDING) {
+		return 0, err
+	}
+	err = windows.GetOverlappedResult(handle, &overlapped, &returned, true)
+	if err != nil {
+		return 0, err
+	}
+	return returned, nil
+}
+
+func buildIoctlInitialize(layer Layer, priority int16, flags Flag) [ioctlSize]byte {
+	var buf [ioctlSize]byte
+	binary.LittleEndian.PutUint32(buf[0:4], uint32(layer))
+	// The driver expects priority + WINDIVERT_PRIORITY_HIGHEST (30000) so
+	// the low range maps to non-negative integers.
+	binary.LittleEndian.PutUint32(buf[4:8], uint32(int32(priority)+int32(PriorityHighest)))
+	binary.LittleEndian.PutUint64(buf[8:16], uint64(flags))
+	return buf
+}
+
+func buildIoctlStartup(filterFlags uint64) [ioctlSize]byte {
+	var buf [ioctlSize]byte
+	binary.LittleEndian.PutUint64(buf[0:8], filterFlags)
+	return buf
+}
+
+// buildIoctlRecv packs a user-space pointer to a WINDIVERT_ADDRESS into
+// the ioctl struct. The driver dereferences it to write the address for
+// the received packet. Caller must keep the Address alive via
+// runtime.KeepAlive.
+func buildIoctlRecv(addr *Address) [ioctlSize]byte {
+	var buf [ioctlSize]byte
+	binary.LittleEndian.PutUint64(buf[0:8], uint64(uintptr(unsafe.Pointer(addr))))
+	binary.LittleEndian.PutUint64(buf[8:16], 0)
+	return buf
+}
+
+func buildIoctlSend(addr *Address) [ioctlSize]byte {
+	var buf [ioctlSize]byte
+	binary.LittleEndian.PutUint64(buf[0:8], uint64(uintptr(unsafe.Pointer(addr))))
+	binary.LittleEndian.PutUint64(buf[8:16], uint64(unsafe.Sizeof(Address{})))
+	return buf
+}
diff --git a/transport/internet/tls/tlsspoof/windivert/windivert.go b/transport/internet/tls/tlsspoof/windivert/windivert.go
new file mode 100644
index 000000000000..9d309886cbe3
--- /dev/null
+++ b/transport/internet/tls/tlsspoof/windivert/windivert.go
@@ -0,0 +1,78 @@
+// Package windivert provides a pure-Go binding to the WinDivert kernel
+// driver on Windows (amd64 and 386). User-mode WinDivert calls are
+// reimplemented in Go; only the signed kernel driver is embedded as an
+// asset, since SCM-installed drivers must live on disk and their
+// Authenticode signature forbids modification.
+//
+// Administrator is required for the first Open in a process so SCM can
+// load the driver. Upstream: https://github.com/basil00/WinDivert v2.2.2,
+// redistributed under its LGPL v3 option; see assets/LICENSE.txt.
+package windivert
+
+import "unsafe"
+
+const AssetVersion = "2.2.2"
+
+// MTUMax is WINDIVERT_MTU_MAX from windivert.h (40 + 0xFFFF). Suitable as
+// a single-packet receive buffer size.
+const MTUMax = 40 + 0xFFFF
+
+type Layer uint32
+
+const LayerNetwork Layer = 0
+
+type Flag uint64
+
+const (
+	// FlagSniff opens a passive observer: the driver copies matching packets
+	// to userspace without removing them from the network stack. Send is not
+	// required (and not allowed) on a sniffing handle.
+	FlagSniff Flag = 0x0001
+	// FlagSendOnly opens a write-only injection handle; Recv is not allowed.
+	FlagSendOnly Flag = 0x0008
+)
+
+const (
+	PriorityHighest int16 = 30000
+	PriorityLowest  int16 = -30000
+)
+
+// Address mirrors WINDIVERT_ADDRESS from windivert.h (80 bytes,
+// little-endian on both amd64 and 386):
+//
+//	 0: INT64  Timestamp
+//	 8: UINT32 bitfield: Layer:8 | Event:8 | flags | Reserved1:8
+//	12: UINT32 Reserved2
+//	16: 64 bytes union (WINDIVERT_DATA_NETWORK / FLOW / SOCKET / REFLECT)
+type Address struct {
+	Timestamp int64
+	bits      uint32
+	Reserved2 uint32
+	union     [64]byte
+}
+
+var _ [80]byte = [unsafe.Sizeof(Address{})]byte{}
+
+// Bit positions inside the Address's packed flags word.
+const (
+	addrBitIPv6        = 20
+	addrBitIPChecksum  = 21
+	addrBitTCPChecksum = 22
+)
+
+func getFlagBit(bits uint32, pos uint) bool { return bits&(1<<pos) != 0 }
+func setFlagBit(bits uint32, pos uint, v bool) uint32 {
+	if v {
+		return bits | (1 << pos)
+	}
+	return bits &^ (1 << pos)
+}
+
+func (a *Address) IPv6() bool { return getFlagBit(a.bits, addrBitIPv6) }
+func (a *Address) SetIPChecksum(v bool) {
+	a.bits = setFlagBit(a.bits, addrBitIPChecksum, v)
+}
+
+func (a *Address) SetTCPChecksum(v bool) {
+	a.bits = setFlagBit(a.bits, addrBitTCPChecksum, v)
+}
diff --git a/transport/internet/websocket/dialer.go b/transport/internet/websocket/dialer.go
index 8e295da062e8..f6eb73e1edae 100644
--- a/transport/internet/websocket/dialer.go
+++ b/transport/internet/websocket/dialer.go
@@ -94,6 +94,14 @@ func dialWebSocket(ctx context.Context, dest net.Destination, streamSettings *in
 					pconn = newConn
 				}
 
+				// Wrap with TLS spoofing if configured
+				if spoofConn, err := tls.WrapWithSpoof(pconn, tConfig.Spoof, tConfig.SpoofMethod, tConfig.SpoofCount, tlsConfig.ServerName); err != nil {
+					pconn.Close()
+					return nil, err
+				} else {
+					pconn = spoofConn
+				}
+
 				// TLS and apply the handshake
 				cn := tls.UClient(pconn, tlsConfig, fingerprint).(*tls.UConn)
 				if err := cn.WebsocketHandshakeContext(ctx); err != nil {