Do not create Finalmask if not needed

https://github.com/XTLS/Xray-core/pull/6816#issuecomment-5828082031
https://github.com/XTLS/Xray-core/issues/6794#issuecomment-5847200576
https://github.com/XTLS/Xray-core/pull/6834#issuecomment-5860728689

Fixes https://github.com/XTLS/Xray-core/issues/6794#issuecomment-5754894283
Fixes https://github.com/XTLS/Xray-core/issues/6124#issuecomment-4439918073
Fixes https://github.com/XTLS/Xray-core/issues/4878#issuecomment-5754638401

---------

Co-authored-by: Artem Lytkin <146867384+4RH1T3CT0R7@users.noreply.github.com>

.github/workflows/test.yml

@@ -67,9 +67,7 @@ jobs:
           check-latest: true
           cache: false
       - name: Check Format
-        run: |
-          go install -v mvdan.cc/gofumpt@latest
-          go run ./infra/vformat/main.go -mode check -pwd ./
+        run: go run ./infra/vformat/main.go -mode check -pwd ./
 
   test:
     needs: check-assets

app/dispatcher/fakednssniffer.go

@@ -23,7 +23,7 @@ func newFakeDNSSniffer(ctx context.Context) (protocolSnifferWithMetadata, error)
 	}
 
 	if fakeDNSEngine == nil {
-		errNotInit := errors.New("FakeDNSEngine is not initialized, but such a sniffer is used").AtError()
+		errNotInit := errors.New("FakeDNSEngine is not initialized, but such a sniffer is used")
 		return protocolSnifferWithMetadata{}, errNotInit
 	}
 	return protocolSnifferWithMetadata{protocolSniffer: func(ctx context.Context, bytes []byte) (SniffResult, error) {

app/dns/config.go

@@ -28,7 +28,7 @@ func toNetIP(addrs []net.Address) ([]net.IP, error) {
 		if addr.Family().IsIP() {
 			ips = append(ips, addr.IP())
 		} else {
-			return nil, errors.New("Failed to convert address", addr, "to Net IP.").AtWarning()
+			return nil, errors.New("Failed to convert address", addr, "to Net IP.")
 		}
 	}
 	return ips, nil

app/dns/dns.go

@@ -212,6 +212,28 @@ func (s *DNS) IsOwnLink(ctx context.Context) bool {
 	return false
 }
 
+// MayUseSystemResolver reports whether any name server configured here could
+// still resolve through the system resolver. That is what happens when no name
+// server is configured at all, and it is also what a name server pointed at
+// "localhost" does. Callers that are about to redirect the system resolver need
+// to know, because a resolution path that reaches it would then loop back to
+// them.
+//
+// Any such server is enough: name servers can be selected per domain, so a
+// single local one makes some query reach the system resolver even when
+// independent upstreams are configured alongside it.
+func (s *DNS) MayUseSystemResolver() bool {
+	if len(s.clients) == 0 {
+		return true
+	}
+	for _, client := range s.clients {
+		if _, isLocal := client.server.(*LocalNameServer); isLocal {
+			return true
+		}
+	}
+	return false
+}
+
 // LookupIP implements dns.Client.
 func (s *DNS) LookupIP(domain string, option dns.IPOption) ([]net.IP, uint32, error) {
 	// Normalize the FQDN form query

app/dns/dns_internal_test.go

@@ -0,0 +1,59 @@
+package dns
+
+import (
+	"context"
+	"testing"
+
+	"github.com/xtls/xray-core/common/net"
+	feature_dns "github.com/xtls/xray-core/features/dns"
+)
+
+// fakeServer stands in for any name server that is not the system resolver.
+type fakeServer struct{}
+
+func (fakeServer) Name() string         { return "fake" }
+func (fakeServer) IsDisableCache() bool { return false }
+func (fakeServer) QueryIP(context.Context, string, feature_dns.IPOption) ([]net.IP, uint32, error) {
+	return nil, 0, nil
+}
+
+// Callers that are about to redirect the system resolver rely on this to tell
+// whether any resolution path could still reach the system resolver, so the
+// mixed shape has to be reported as reachable: a domain-specific rule can
+// select the system resolver even when an independent upstream also exists.
+func TestMayUseSystemResolver(t *testing.T) {
+	tests := []struct {
+		name    string
+		clients []*Client
+		want    bool
+	}{
+		{
+			name: "no clients at all",
+			want: true,
+		},
+		{
+			name:    "only the system resolver",
+			clients: []*Client{{server: NewLocalNameServer()}},
+			want:    true,
+		},
+		{
+			name:    "the system resolver alongside an independent name server",
+			clients: []*Client{{server: fakeServer{}}, {server: NewLocalNameServer()}},
+			want:    true,
+		},
+		{
+			name:    "only independent name servers",
+			clients: []*Client{{server: fakeServer{}}},
+			want:    false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			server := &DNS{clients: tt.clients}
+			if got := server.MayUseSystemResolver(); got != tt.want {
+				t.Errorf("MayUseSystemResolver() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

app/dns/dnscommon.go

@@ -188,10 +188,10 @@ func parseResponse(payload []byte) (*IPRecord, error) {
 	var parser dnsmessage.Parser
 	h, err := parser.Start(payload)
 	if err != nil {
-		return nil, errors.New("failed to parse DNS response").Base(err).AtWarning()
+		return nil, errors.New("failed to parse DNS response").Base(err)
 	}
 	if err := parser.SkipAllQuestions(); err != nil {
-		return nil, errors.New("failed to skip questions in DNS response").Base(err).AtWarning()
+		return nil, errors.New("failed to skip questions in DNS response").Base(err)
 	}
 
 	now := time.Now()

app/dns/fakedns/fake.go

@@ -58,7 +58,7 @@ func NewFakeDNSHolder() (*Holder, error) {
 	var err error
 
 	if fkdns, err = NewFakeDNSHolderConfigOnly(nil); err != nil {
-		return nil, errors.New("Unable to create Fake Dns Engine").Base(err).AtError()
+		return nil, errors.New("Unable to create Fake Dns Engine").Base(err)
 	}
 	err = fkdns.initialize(dns.FakeIPv4Pool, 65535)
 	if err != nil {
@@ -80,13 +80,13 @@ func (fkdns *Holder) initialize(ipPoolCidr string, lruSize int) error {
 	var err error
 
 	if _, ipRange, err = net.ParseCIDR(ipPoolCidr); err != nil {
-		return errors.New("Unable to parse CIDR for Fake DNS IP assignment").Base(err).AtError()
+		return errors.New("Unable to parse CIDR for Fake DNS IP assignment").Base(err)
 	}
 
 	ones, bits := ipRange.Mask.Size()
 	rooms := bits - ones
 	if math.Log2(float64(lruSize)) >= float64(rooms) {
-		return errors.New("LRU size is bigger than subnet size").AtError()
+		return errors.New("LRU size is bigger than subnet size")
 	}
 	fkdns.domainToIP = cache.NewLru(lruSize)
 	fkdns.ipRange = ipRange

app/dns/nameserver.go

@@ -84,7 +84,7 @@ func NewServer(ctx context.Context, dest net.Destination, dispatcher routing.Dis
 	if dest.Network == net.Network_UDP { // UDP classic DNS mode
 		return NewClassicNameServer(dest, dispatcher, disableCache, serveStale, serveExpiredTTL, clientIP), nil
 	}
-	return nil, errors.New("No available name server could be created from ", dest).AtWarning()
+	return nil, errors.New("No available name server could be created from ", dest)
 }
 
 // NewClient creates a DNS client managing a name server with client IP, domain rules and expected IPs.
@@ -102,7 +102,7 @@ func NewClient(
 		// Create a new server for each client for now
 		server, err := NewServer(ctx, ns.Address.AsDestination(), dispatcher, disableCache, serveStale, serveExpiredTTL, clientIP)
 		if err != nil {
-			return errors.New("failed to create nameserver").Base(err).AtWarning()
+			return errors.New("failed to create nameserver").Base(err)
 		}
 
 		_, isLocalDNS := server.(*LocalNameServer)
@@ -113,7 +113,7 @@ func NewClient(
 		if len(ns.ExpectedIp) > 0 {
 			expectedMatcher, err = geodata.IPReg.BuildIPMatcher(ns.ExpectedIp)
 			if err != nil {
-				return errors.New("failed to create expected ip matcher").Base(err).AtWarning()
+				return errors.New("failed to create expected ip matcher").Base(err)
 			}
 		}
 
@@ -122,7 +122,7 @@ func NewClient(
 		if len(ns.UnexpectedIp) > 0 {
 			unexpectedMatcher, err = geodata.IPReg.BuildIPMatcher(ns.UnexpectedIp)
 			if err != nil {
-				return errors.New("failed to create unexpected ip matcher").Base(err).AtWarning()
+				return errors.New("failed to create unexpected ip matcher").Base(err)
 			}
 		}
 

app/dns/nameserver_fakedns.go

@@ -27,7 +27,7 @@ func (s *FakeDNSServer) IsDisableCache() bool {
 
 func (f *FakeDNSServer) QueryIP(ctx context.Context, domain string, opt dns.IPOption) ([]net.IP, uint32, error) {
 	if f.fakeDNSEngine == nil {
-		return nil, 0, errors.New("Unable to locate a fake DNS Engine").AtError()
+		return nil, 0, errors.New("Unable to locate a fake DNS Engine")
 	}
 
 	var ips []net.Address
@@ -39,7 +39,7 @@ func (f *FakeDNSServer) QueryIP(ctx context.Context, domain string, opt dns.IPOp
 
 	netIP, err := toNetIP(ips)
 	if err != nil {
-		return nil, 0, errors.New("Unable to convert IP to net ip").Base(err).AtError()
+		return nil, 0, errors.New("Unable to convert IP to net ip").Base(err)
 	}
 
 	errors.LogInfo(ctx, f.Name(), " got answer: ", domain, " -> ", ips)

app/log/log.go

@@ -89,10 +89,10 @@ func (g *Instance) startInternal() error {
 	g.active = true
 
 	if err := g.initAccessLogger(); err != nil {
-		return errors.New("failed to initialize access logger").Base(err).AtWarning()
+		return errors.New("failed to initialize access logger").Base(err)
 	}
 	if err := g.initErrorLogger(); err != nil {
-		return errors.New("failed to initialize error logger").Base(err).AtWarning()
+		return errors.New("failed to initialize error logger").Base(err)
 	}
 
 	return nil
@@ -141,6 +141,10 @@ func (g *Instance) Handle(msg log.Message) {
 	}
 }
 
+func (g *Instance) Severity() log.Severity {
+	return g.config.ErrorLogLevel
+}
+
 // Close implements common.Closable.Close().
 func (g *Instance) Close() error {
 	errors.LogDebug(context.Background(), "Logger closing")

app/proxyman/inbound/always.go

@@ -66,7 +66,7 @@ func NewAlwaysOnInboundHandler(ctx context.Context, tag string, receiverConfig *
 	}
 	mss, err := internet.ToMemoryStreamConfig(receiverConfig.StreamSettings)
 	if err != nil {
-		return nil, errors.New("failed to parse stream config").Base(err).AtWarning()
+		return nil, errors.New("failed to parse stream config").Base(err)
 	}
 
 	newCtx := session.ContextWithInbound(ctx, &session.Inbound{Tag: tag, Source: src})

app/proxyman/inbound/inbound.go

@@ -165,7 +165,7 @@ func NewHandler(ctx context.Context, config *core.InboundHandlerConfig) (inbound
 
 	receiverSettings, ok := rawReceiverSettings.(*proxyman.ReceiverConfig)
 	if !ok {
-		return nil, errors.New("not a ReceiverConfig").AtError()
+		return nil, errors.New("not a ReceiverConfig")
 	}
 
 	streamSettings := receiverSettings.StreamSettings

app/proxyman/inbound/worker.go

@@ -142,7 +142,7 @@ func (w *tcpWorker) Start() error {
 		go w.callback(conn)
 	})
 	if err != nil {
-		return errors.New("failed to listen TCP on ", w.port).AtWarning().Base(err)
+		return errors.New("failed to listen TCP on ", w.port).Base(err)
 	}
 	w.hub = hub
 	return nil
@@ -528,7 +528,7 @@ func (w *dsWorker) Start() error {
 		go w.callback(conn)
 	})
 	if err != nil {
-		return errors.New("failed to listen Unix Domain Socket on ", w.address).AtWarning().Base(err)
+		return errors.New("failed to listen Unix Domain Socket on ", w.address).Base(err)
 	}
 	w.hub = hub
 	return nil

app/proxyman/outbound/handler.go

@@ -87,7 +87,7 @@ func NewHandler(ctx context.Context, config *core.OutboundHandlerConfig) (outbou
 			h.senderSettings = s
 			mss, err := internet.ToMemoryStreamConfig(s.StreamSettings)
 			if err != nil {
-				return nil, errors.New("failed to parse stream settings").Base(err).AtWarning()
+				return nil, errors.New("failed to parse stream settings").Base(err)
 			}
 			h.streamSettings = mss
 		default:
@@ -217,7 +217,7 @@ func (h *Handler) Dispatch(ctx context.Context, link *transport.Link) {
 		if ob.Target.Network == net.Network_UDP && ob.Target.Port == 443 {
 			switch h.udp443 {
 			case "reject":
-				test(errors.New("XUDP rejected UDP/443 traffic").AtInfo())
+				test(errors.New("XUDP rejected UDP/443 traffic"))
 				return
 			case "skip":
 				goto out

app/reverse/portal.go

@@ -68,13 +68,13 @@ func (p *Portal) HandleConnection(ctx context.Context, link *transport.Link) err
 	outbounds := session.OutboundsFromContext(ctx)
 	ob := outbounds[len(outbounds)-1]
 	if ob == nil {
-		return errors.New("outbound metadata not found").AtError()
+		return errors.New("outbound metadata not found")
 	}
 
 	if isDomain(ob.Target, p.domain) {
 		muxClient, err := mux.NewClientWorker(*link, mux.ClientStrategy{})
 		if err != nil {
-			return errors.New("failed to create mux client worker").Base(err).AtWarning()
+			return errors.New("failed to create mux client worker").Base(err)
 		}
 
 		worker, err := NewPortalWorker(muxClient)

app/router/config.go

@@ -115,7 +115,7 @@ func (rr *RoutingRule) BuildCondition() (Condition, error) {
 	}
 
 	if conds.Len() == 0 {
-		return nil, errors.New("this rule has no effective fields").AtWarning()
+		return nil, errors.New("this rule has no effective fields")
 	}
 
 	return conds, nil
@@ -145,7 +145,7 @@ func (br *BalancingRule) Build(ohm outbound.Manager, dispatcher routing.Dispatch
 		}
 		s, ok := i.(*StrategyLeastLoadConfig)
 		if !ok {
-			return nil, errors.New("not a StrategyLeastLoadConfig").AtError()
+			return nil, errors.New("not a StrategyLeastLoadConfig")
 		}
 		leastLoadStrategy := NewLeastLoadStrategy(s)
 		return &Balancer{

common/buf/readv_windows.go

@@ -5,7 +5,8 @@ import (
 )
 
 type windowsReader struct {
-	bufs []syscall.WSABuf
+	bufs  []syscall.WSABuf
+	ready bool
 }
 
 func (r *windowsReader) Init(bs []*Buffer) {
@@ -15,6 +16,7 @@ func (r *windowsReader) Init(bs []*Buffer) {
 	for _, b := range bs {
 		r.bufs = append(r.bufs, syscall.WSABuf{Len: uint32(Size), Buf: &b.v[0]})
 	}
+	r.ready = false
 }
 
 func (r *windowsReader) Clear() {
@@ -25,6 +27,14 @@ func (r *windowsReader) Clear() {
 }
 
 func (r *windowsReader) Read(fd uintptr) int32 {
+	// On the first invocation, we return -1 to indicate "not ready"
+	// to make rawConn.Read wait for readability using the runtime's own mechanism
+	// because syscall.WSARecv() is a blocking call when used with nil OVERLAPPED
+	if !r.ready {
+		r.ready = true
+		return -1
+	}
+
 	var nBytes uint32
 	var flags uint32
 	err := syscall.WSARecv(syscall.Handle(fd), &r.bufs[0], uint32(len(r.bufs)), &nBytes, &flags, nil, nil)

common/crypto/crypto.go

@@ -10,12 +10,12 @@ import (
 
 // [,)
 func RandBetween(from int64, to int64) int64 {
-	if from == to {
-		return from
-	}
 	if from > to {
 		from, to = to, from
 	}
+	if d := to - from; d == 0 || d == 1 {
+		return from
+	}
 	bigInt, _ := rand.Int(rand.Reader, big.NewInt(to-from))
 	return from + bigInt.Int64()
 }

common/errors/errors.go

@@ -18,17 +18,12 @@ type hasInnerError interface {
 	Unwrap() error
 }
 
-type hasSeverity interface {
-	Severity() log.Severity
-}
-
 // Error is an error object with underlying error.
 type Error struct {
-	prefix   []interface{}
-	message  []interface{}
-	caller   string
-	inner    error
-	severity log.Severity
+	prefix  []interface{}
+	message []interface{}
+	caller  string
+	inner   error
 }
 
 // Error implements error.Error().
@@ -69,46 +64,6 @@ func (err *Error) Base(e error) *Error {
 	return err
 }
 
-func (err *Error) atSeverity(s log.Severity) *Error {
-	err.severity = s
-	return err
-}
-
-func (err *Error) Severity() log.Severity {
-	if err.inner == nil {
-		return err.severity
-	}
-
-	if s, ok := err.inner.(hasSeverity); ok {
-		as := s.Severity()
-		if as < err.severity {
-			return as
-		}
-	}
-
-	return err.severity
-}
-
-// AtDebug sets the severity to debug.
-func (err *Error) AtDebug() *Error {
-	return err.atSeverity(log.Severity_Debug)
-}
-
-// AtInfo sets the severity to info.
-func (err *Error) AtInfo() *Error {
-	return err.atSeverity(log.Severity_Info)
-}
-
-// AtWarning sets the severity to warning.
-func (err *Error) AtWarning() *Error {
-	return err.atSeverity(log.Severity_Warning)
-}
-
-// AtError sets the severity to error.
-func (err *Error) AtError() *Error {
-	return err.atSeverity(log.Severity_Error)
-}
-
 // String returns the string representation of this error.
 func (err *Error) String() string {
 	return err.Error()
@@ -132,9 +87,8 @@ func New(msg ...interface{}) *Error {
 		details = details[:i]
 	}
 	return &Error{
-		message:  msg,
-		severity: log.Severity_Info,
-		caller:   details,
+		message: msg,
+		caller:  details,
 	}
 }
 
@@ -171,6 +125,9 @@ func LogErrorInner(ctx context.Context, inner error, msg ...interface{}) {
 }
 
 func doLog(ctx context.Context, inner error, severity log.Severity, msg ...interface{}) {
+	if log.GetSeverity() < severity {
+		return
+	}
 	pc, _, _, _ := runtime.Caller(2)
 	details := runtime.FuncForPC(pc).Name()
 	if len(details) >= trim {
@@ -181,10 +138,9 @@ func doLog(ctx context.Context, inner error, severity log.Severity, msg ...inter
 		details = details[:i]
 	}
 	err := &Error{
-		message:  msg,
-		severity: severity,
-		caller:   details,
-		inner:    inner,
+		message: msg,
+		caller:  details,
+		inner:   inner,
 	}
 	if ctx != nil && ctx != context.Background() {
 		id := uint32(c.IDFromContext(ctx))
@@ -193,7 +149,7 @@ func doLog(ctx context.Context, inner error, severity log.Severity, msg ...inter
 		}
 	}
 	log.Record(&log.GeneralMessage{
-		Severity: GetSeverity(err),
+		Severity: severity,
 		Content:  err,
 	})
 }
@@ -217,11 +173,3 @@ L:
 	}
 	return err
 }
-
-// GetSeverity returns the actual severity of the error, including inner errors.
-func GetSeverity(err error) log.Severity {
-	if s, ok := err.(hasSeverity); ok {
-		return s.Severity()
-	}
-	return log.Severity_Info
-}

common/errors/errors_test.go

@@ -7,30 +7,21 @@ import (
 
 	"github.com/google/go-cmp/cmp"
 	. "github.com/xtls/xray-core/common/errors"
-	"github.com/xtls/xray-core/common/log"
 )
 
 func TestError(t *testing.T) {
 	err := New("TestError")
-	if v := GetSeverity(err); v != log.Severity_Info {
-		t.Error("severity: ", v)
+	if v := err.Error(); !strings.Contains(v, "TestError") {
+		t.Error("error: ", v)
 	}
 
 	err = New("TestError2").Base(io.EOF)
-	if v := GetSeverity(err); v != log.Severity_Info {
-		t.Error("severity: ", v)
+	if v := err.Error(); !strings.Contains(v, "EOF") {
+		t.Error("error: ", v)
 	}
 
-	err = New("TestError3").Base(io.EOF).AtWarning()
-	if v := GetSeverity(err); v != log.Severity_Warning {
-		t.Error("severity: ", v)
-	}
-
-	err = New("TestError4").Base(io.EOF).AtWarning()
-	err = New("TestError5").Base(err)
-	if v := GetSeverity(err); v != log.Severity_Warning {
-		t.Error("severity: ", v)
-	}
+	err = New("TestError3").Base(io.EOF)
+	err = New("TestError4").Base(err)
 	if v := err.Error(); !strings.Contains(v, "EOF") {
 		t.Error("error: ", v)
 	}

common/geodata/strmatcher/benchmark_matchers_test.go

@@ -1,6 +1,7 @@
 package strmatcher_test
 
 import (
+	"regexp"
 	"strconv"
 	"testing"
 
@@ -72,6 +73,64 @@ func BenchmarkSubstrMatcher(b *testing.B) {
 	})
 }
 
+func BenchmarkRegexMatcher(b *testing.B) {
+	patterns := []string{ // taken from geosite
+		`(^|\.)91porn\.(best|com|cool|fun|group|party|plus|site|tw|work)$`,
+		`(^|\.)91porn[0-9]{3}\.me$`,
+		`(^|\.)apiproxy-device-prod-nlb-.+\.amazonaws\.com$`,
+		`(^|\.)dualstack\.apiproxy-.+\.amazonaws\.com$`,
+		`(^|\.)aqdk[0-9]{3}\.com$`,
+		`(^|\.)bilibili3(0[1-9]|1[0-2])\.xyz$`,
+		`(^|\.)byyum([3589]|2[235689]|3[34]|4[1-9]|5[1-79]|6[0134679])?\.com$`,
+		`(^|\.)fiftymvapi\..+$`,
+		`(^|\.)gossipfuli[0-9]{3,4}\.xyz$`,
+		`(^|\.)kpkuang\.(bond|fun|info|one|us)$`,
+		`(^|\.)rule34\.(asia|us|world|xxx|xyz)$`,
+		`(^|\.)[a-z][1-9][0-9][a-z]\.com$`,
+		`.+\.awsdns-[0-9][0-9]\.(co\.uk|com|net|org)$`,
+		`.+\.dkr\.ecr\.[^\.]+\.amazonaws\.com$`,
+		`^(.+\.)*zh\.okaapps\.com$`,
+		`^cdn\d-epicgames-\d+\.file\.myqcloud\.com$`,
+		`^chatgpt-async-webps-prod-\S+-\d+\.webpubsub\.azure\.com$`,
+		`^r+[0-9]+(---|\.)sn-(2x3|ni5|j5o)\w{5}\.googlevideo\.com$`,
+		`^speed\.(coe|open)\.ad\.[a-z]{2,6}\.prod\.hosts\.ooklaserver\.net$`,
+		`javdb\d+\.com$`,
+	}
+	domains := []string{
+		"www.google.com", "rr3---sn-4g5edndy.googlevideo.com", "r1---sn-2x3abcde.googlevideo.com", "i.ytimg.com",
+		"graph.facebook.com", "api.twitter.com", "www.baidu.com", "github.com", "objects.githubusercontent.com",
+		"login.microsoftonline.com", "e1234.dscb.akamaiedge.net", "d1a2b3c4d5e6f7.cloudfront.net",
+		"s3.us-east-1.amazonaws.com", "123456789012.dkr.ecr.us-east-1.amazonaws.com", "www.wikipedia.org",
+		"discord.com", "telegram.org", "store.steampowered.com", "www.91porn.com", "ns-1234.awsdns-12.org",
+	}
+	bench := func(b *testing.B, ctor func(pattern string) func(string) bool) {
+		var matchers []func(string) bool
+		for _, p := range patterns {
+			matchers = append(matchers, ctor(p))
+		}
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			for _, d := range domains {
+				for _, match := range matchers {
+					_ = match(d)
+				}
+			}
+		}
+	}
+	b.Run("regexp", func(b *testing.B) {
+		bench(b, func(pattern string) func(string) bool {
+			return regexp.MustCompile(pattern).MatchString
+		})
+	})
+	b.Run("prefilter", func(b *testing.B) {
+		bench(b, func(pattern string) func(string) bool {
+			m, err := Regex.New(pattern)
+			common.Must(err)
+			return m.Match
+		})
+	})
+}
+
 // Utility functions for benchmark
 
 func benchmarkMatcherType(b *testing.B, t Type, ctor func() MatcherGroup) {

common/geodata/strmatcher/matchergroup_mph.go

@@ -1,6 +1,8 @@
 package strmatcher
 
 import (
+	"errors"
+	"math"
 	"math/bits"
 	"runtime"
 	"sort"
@@ -38,19 +40,21 @@ type mphRuleInfo struct {
 // MphMatcherGroup is an implementation of MatcherGroup.
 // It implements Rabin-Karp algorithm and minimal perfect hash table for Full and Domain matcher.
 type MphMatcherGroup struct {
-	rules      []string   // RuleIdx -> pattern string, index 0 reserved for failed lookup
-	values     [][]uint32 // RuleIdx -> registered matcher values for the pattern (Full Matcher takes precedence)
-	level0     []uint32   // RollingHash & Mask -> seed for Memhash
-	level0Mask uint32     // Mask restricting RollingHash to 0 ~ len(level0)
-	level1     []uint32   // Memhash<seed> & Mask -> stored index for rules
-	level1Mask uint32     // Mask for restricting Memhash<seed> to 0 ~ len(level1)
-	ruleInfos  *map[string]mphRuleInfo
+	patterns    string   // All rule patterns concatenated
+	patternOffs []uint32 // RuleIdx -> patterns[patternOffs[i]:patternOffs[i+1]], index 0 reserved for failed lookup
+	values      []uint32 // All registered matcher values concatenated
+	valueOffs   []uint32 // RuleIdx -> values[valueOffs[i]:valueOffs[i+1]] (Full Matcher takes precedence)
+	level0      []uint32 // RollingHash & Mask -> seed for Memhash
+	level0Mask  uint32   // Mask restricting RollingHash to 0 ~ len(level0)
+	level1      []uint32 // Memhash<seed> & Mask -> stored index for rules
+	level1Mask  uint32   // Mask for restricting Memhash<seed> to 0 ~ len(level1)
+	rules       []string // RuleIdx -> pattern string, only used for building
+	ruleInfos   *map[string]mphRuleInfo
 }
 
 func NewMphMatcherGroup() *MphMatcherGroup {
 	return &MphMatcherGroup{
 		rules:      []string{""},
-		values:     [][]uint32{nil},
 		level0:     nil,
 		level0Mask: 0,
 		level1:     nil,
@@ -78,7 +82,6 @@ func (g *MphMatcherGroup) addPattern(suffixHash uint32, suffixPattern string, pa
 	if !found {
 		info = mphRuleInfo{rollingHash: RollingHash(suffixHash, pattern)}
 		g.rules = append(g.rules, fullPattern)
-		g.values = append(g.values, nil)
 	}
 	info.matchers[matcherType] = append(info.matchers[matcherType], value)
 	(*g.ruleInfos)[fullPattern] = info
@@ -94,14 +97,30 @@ func (g *MphMatcherGroup) Build() error {
 	g.level1 = make([]uint32, nextPow2(ruleCount))
 	g.level1Mask = uint32(len(g.level1) - 1)
 
+	// Flatten patterns and values so the built group has no per-rule objects
+	valueCount := 0
+	for _, ruleInfo := range *g.ruleInfos {
+		valueCount += len(ruleInfo.matchers[Full]) + len(ruleInfo.matchers[Domain])
+	}
+	g.patterns = strings.Join(g.rules, "")
+	if uint64(len(g.patterns)) > math.MaxUint32 || uint64(valueCount) > math.MaxUint32 {
+		return errors.New("too many rules for MphMatcherGroup")
+	}
+	g.patternOffs = make([]uint32, len(g.rules)+1)
+	g.values = make([]uint32, 0, valueCount)
+	g.valueOffs = make([]uint32, len(g.rules)+1)
+
 	// Create buckets based on all rule's rolling hash
 	buckets := make([][]uint32, len(g.level0))
 	for ruleIdx := 1; ruleIdx < len(g.rules); ruleIdx++ { // Traverse rules starting from index 1 (0 reserved for failed lookup)
 		ruleInfo := (*g.ruleInfos)[g.rules[ruleIdx]]
 		bucketIdx := ruleInfo.rollingHash & g.level0Mask
 		buckets[bucketIdx] = append(buckets[bucketIdx], uint32(ruleIdx))
-		g.values[ruleIdx] = append(ruleInfo.matchers[Full], ruleInfo.matchers[Domain]...) // nolint:gocritic
+		g.patternOffs[ruleIdx+1] = g.patternOffs[ruleIdx] + uint32(len(g.rules[ruleIdx]))
+		g.values = append(append(g.values, ruleInfo.matchers[Full]...), ruleInfo.matchers[Domain]...)
+		g.valueOffs[ruleIdx+1] = uint32(len(g.values))
 	}
+	g.rules = nil
 	g.ruleInfos = nil // Set ruleInfos nil to release memory
 	runtime.GC()      // peak mem
 
@@ -121,7 +140,7 @@ func (g *MphMatcherGroup) Build() error {
 		seed := uint32(0)
 		for len(hashedBucket) != len(bucket) {
 			for _, ruleIdx := range bucket {
-				memHash := MemHash(seed, g.rules[ruleIdx]) & g.level1Mask
+				memHash := MemHash(seed, g.pattern(ruleIdx)) & g.level1Mask
 				if occupied[memHash] { // Collision occurred with this seed
 					for _, hash := range hashedBucket { // Revert all values in this hashed bucket
 						occupied[hash] = false
@@ -141,12 +160,26 @@ func (g *MphMatcherGroup) Build() error {
 	return nil
 }
 
+func (g *MphMatcherGroup) pattern(ruleIdx uint32) string {
+	return g.patterns[g.patternOffs[ruleIdx]:g.patternOffs[ruleIdx+1]]
+}
+
+// valuesOf caps the capacity, so appending to a Match result can't overwrite the next rule's values.
+func (g *MphMatcherGroup) valuesOf(ruleIdx uint32) []uint32 {
+	start, end := g.valueOffs[ruleIdx], g.valueOffs[ruleIdx+1]
+	return g.values[start:end:end]
+}
+
 // Lookup searches for input in minimal perfect hash table and returns its index. 0 indicates not found.
 func (g *MphMatcherGroup) Lookup(rollingHash uint32, input string) uint32 {
 	i0 := rollingHash & g.level0Mask
 	seed := g.level0[i0]
 	i1 := MemHash(seed, input) & g.level1Mask
-	if n := g.level1[i1]; g.rules[n] == input {
+	n := g.level1[i1]
+	// Build only puts valid rule indices in level1, so n+1 < len(patternOffs) and the span is inside patterns.
+	// Skip the bounds checks, they made this hot path measurably slower than indexing a []string
+	offs := (*[2]uint32)(unsafe.Add(unsafe.Pointer(unsafe.SliceData(g.patternOffs)), uintptr(n)*4))
+	if start := offs[0]; int(offs[1]-start) == len(input) && unsafe.String((*byte)(unsafe.Add(unsafe.Pointer(unsafe.StringData(g.patterns)), start)), len(input)) == input {
 		return n
 	}
 	return 0
@@ -160,12 +193,12 @@ func (g *MphMatcherGroup) Match(input string) []uint32 {
 		hash = hash*PrimeRK + uint32(input[i])
 		if input[i] == '.' {
 			if mphIdx := g.Lookup(hash, input[i:]); mphIdx != 0 {
-				matches = append(matches, g.values[mphIdx])
+				matches = append(matches, g.valuesOf(mphIdx))
 			}
 		}
 	}
 	if mphIdx := g.Lookup(hash, input); mphIdx != 0 {
-		matches = append(matches, g.values[mphIdx])
+		matches = append(matches, g.valuesOf(mphIdx))
 	}
 	return CompositeMatchesReverse(matches)
 }

common/geodata/strmatcher/matchergroup_mph_test.go

@@ -1,7 +1,9 @@
 package strmatcher_test
 
 import (
+	"math/rand"
 	"reflect"
+	"slices"
 	"testing"
 
 	"github.com/xtls/xray-core/common"
@@ -276,3 +278,63 @@ func TestEmptyMphMatcherGroup(t *testing.T) {
 		t.Error("Expect [], but ", r)
 	}
 }
+
+func TestMphMatcherGroupRandom(t *testing.T) {
+	inputs := []string{""} // All strings over "ab." up to 7 bytes
+	for i := 0; len(inputs[i]) < 7; i++ {
+		for _, c := range []string{"a", "b", "."} {
+			inputs = append(inputs, inputs[i]+c)
+		}
+	}
+	for seed := int64(0); seed < 300; seed++ {
+		r := rand.New(rand.NewSource(seed))
+		g := NewMphMatcherGroup()
+		full, domain := map[string][]uint32{}, map[string][]uint32{} // Stored pattern -> values
+		for value := uint32(r.Intn(200)); value > 0; value-- {
+			pattern := make([]byte, r.Intn(8))
+			for i := range pattern {
+				pattern[i] = "ab."[r.Intn(3)]
+			}
+			if p := string(pattern); r.Intn(2) == 0 {
+				g.AddFullMatcher(FullMatcher(p), value)
+				full[p] = append(full[p], value)
+			} else {
+				g.AddDomainMatcher(DomainMatcher(p), value)
+				domain[p] = append(domain[p], value)
+				domain["."+p] = append(domain["."+p], value)
+			}
+		}
+		g.Build()
+		for _, input := range inputs {
+			keys := []string{input} // Whole input first, then "." suffixes from longest to shortest
+			for i := range len(input) {
+				if input[i] == '.' {
+					keys = append(keys, input[i:])
+				}
+			}
+			var want []uint32
+			for _, k := range keys {
+				want = append(append(want, full[k]...), domain[k]...)
+			}
+			if m := g.Match(input); !slices.Equal(m, want) {
+				t.Fatalf("seed %d: Match(%q) = %v, want %v", seed, input, m, want)
+			}
+			if m := g.MatchAny(input); m != (len(want) > 0) {
+				t.Fatalf("seed %d: MatchAny(%q) = %v", seed, input, m)
+			}
+		}
+	}
+}
+
+func TestMphMatcherGroupAppend(t *testing.T) {
+	g := NewMphMatcherGroup()
+	g.AddFullMatcher(FullMatcher("a.com"), 1)
+	g.AddFullMatcher(FullMatcher("b.com"), 2)
+	g.Build()
+	if m := append(g.Match("a.com"), 3); !slices.Equal(m, []uint32{1, 3}) {
+		t.Error("expect [1 3], but ", m)
+	}
+	if m := g.Match("b.com"); !slices.Equal(m, []uint32{2}) {
+		t.Error("expect [2], but ", m)
+	}
+}

common/geodata/strmatcher/matchers.go

@@ -3,6 +3,7 @@ package strmatcher
 import (
 	"errors"
 	"regexp"
+	"regexp/syntax"
 	"slices"
 	"strings"
 	"unicode/utf8"
@@ -73,7 +74,43 @@ func (m SubstrMatcher) Match(s string) bool {
 
 // RegexMatcher is an implementation of Matcher.
 type RegexMatcher struct {
-	pattern *regexp.Regexp
+	pattern  *regexp.Regexp
+	literals []string // every match contains all of them, longest first
+}
+
+func newRegexMatcher(pattern string) (Matcher, error) {
+	regex, err := regexp.Compile(pattern)
+	if err != nil {
+		return nil, err
+	}
+	m := &RegexMatcher{pattern: regex}
+	if re, err := syntax.Parse(pattern, syntax.Perl); err == nil { // same flags as regexp.Compile
+		m.literals = requiredLiterals(re, nil)
+		slices.SortStableFunc(m.literals, func(a, b string) int { return len(b) - len(a) })
+	}
+	return m, nil
+}
+
+// requiredLiterals appends to dst the case-sensitive strings that every match of re contains.
+func requiredLiterals(re *syntax.Regexp, dst []string) []string {
+	switch re.Op {
+	case syntax.OpLiteral:
+		// regexp matches U+FFFD against invalid UTF-8 bytes, strings.Contains does not
+		if re.Flags&syntax.FoldCase == 0 && !slices.Contains(re.Rune, utf8.RuneError) {
+			dst = append(dst, string(re.Rune))
+		}
+	case syntax.OpCapture, syntax.OpPlus:
+		dst = requiredLiterals(re.Sub[0], dst)
+	case syntax.OpRepeat:
+		if re.Min > 0 {
+			dst = requiredLiterals(re.Sub[0], dst)
+		}
+	case syntax.OpConcat:
+		for _, sub := range re.Sub {
+			dst = requiredLiterals(sub, dst)
+		}
+	}
+	return dst
 }
 
 func (*RegexMatcher) Type() Type {
@@ -89,6 +126,11 @@ func (m *RegexMatcher) String() string {
 }
 
 func (m *RegexMatcher) Match(s string) bool {
+	for _, l := range m.literals {
+		if !strings.Contains(s, l) {
+			return false
+		}
+	}
 	return m.pattern.MatchString(s)
 }
 
@@ -102,11 +144,7 @@ func (t Type) New(pattern string) (Matcher, error) {
 	case Domain:
 		return DomainMatcher(pattern), nil
 	case Regex: // 1. regex matching is case-sensitive
-		regex, err := regexp.Compile(pattern)
-		if err != nil {
-			return nil, err
-		}
-		return &RegexMatcher{pattern: regex}, nil
+		return newRegexMatcher(pattern)
 	default:
 		return nil, errors.New("unknown matcher type")
 	}
@@ -135,11 +173,7 @@ func (t Type) NewDomainPattern(pattern string) (Matcher, error) {
 		}
 		return DomainMatcher(pattern), nil
 	case Regex: // Regex's charset not in LDH subset
-		regex, err := regexp.Compile(pattern)
-		if err != nil {
-			return nil, err
-		}
-		return &RegexMatcher{pattern: regex}, nil
+		return newRegexMatcher(pattern)
 	default:
 		return nil, errors.New("unknown matcher type")
 	}

common/geodata/strmatcher/matchers_regex_test.go

@@ -0,0 +1,60 @@
+package strmatcher
+
+import (
+	"regexp"
+	"slices"
+	"testing"
+)
+
+var regexLiteralCases = []struct {
+	pattern  string
+	literals []string
+}{
+	{`(^|\.)91porn\.(best|com)$`, []string{"91porn."}},
+	{`.+\.awsdns-cn-[0-9][0-9]\.(biz|com|net|top)$`, []string{".awsdns-cn-", "."}},
+	{`^r+[0-9]+(---|\.)sn-(2x3|ni5|j5o)\w{5}\.googlevideo\.com$`, []string{".googlevideo.com", "sn-", "r"}},
+	{`(?i)abc`, nil},
+	{`ab(?i:CD)ef`, []string{"ab", "ef"}},
+	{`(abc)?x`, []string{"x"}},
+	{`(abc)*x`, []string{"x"}},
+	{`x{0,3}yy`, []string{"yy"}},
+	{`(ab)+c{2}`, []string{"ab", "c"}},
+	{`abc|abd`, []string{"ab"}},
+	{`\Qa.b\E`, []string{"a.b"}},
+	{`a\x{FFFD}b`, nil},
+	{`^[^.]+$`, nil},
+}
+
+func TestRegexRequiredLiterals(t *testing.T) {
+	for _, test := range regexLiteralCases {
+		m, err := newRegexMatcher(test.pattern)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if got := m.(*RegexMatcher).literals; !slices.Equal(got, test.literals) {
+			t.Errorf("%s: got %q, want %q", test.pattern, got, test.literals)
+		}
+	}
+}
+
+func FuzzRegexMatcher(f *testing.F) {
+	inputs := []string{
+		"", "x", "yy", "abd", "ccc", "ABC", "abCDef", "abcdef", "abababcc", "a.b", "a\xffb", "a\uFFFDb",
+		"www.91porn.com", "ns1.awsdns-cn-01.top", "r1---sn-2x3abcde.googlevideo.com",
+	}
+	for _, test := range regexLiteralCases {
+		for _, s := range inputs {
+			f.Add(test.pattern, s)
+		}
+	}
+	f.Fuzz(func(t *testing.T, pattern, s string) {
+		re, err := regexp.Compile(pattern)
+		if err != nil {
+			return
+		}
+		m, _ := newRegexMatcher(pattern)
+		if got, want := m.Match(s), re.MatchString(s); got != want {
+			t.Errorf("pattern %q, input %q: got %v, want %v", pattern, s, got, want)
+		}
+	})
+}

common/log/log.go

@@ -1,7 +1,7 @@
 package log // import "github.com/xtls/xray-core/common/log"
 
 import (
-	"sync"
+	"sync/atomic"
 
 	"github.com/xtls/xray-core/common/serial"
 )
@@ -29,36 +29,32 @@ func (m *GeneralMessage) String() string {
 
 // Record writes a message into log stream.
 func Record(msg Message) {
-	logHandler.Handle(msg)
+	if h := logHandler.Load(); h != nil {
+		(*h).Handle(msg)
+	}
 }
 
-var logHandler syncHandler
+type SeverityLogger interface {
+	Handler
+	Severity() Severity
+}
+
+func GetSeverity() Severity {
+	if h := logHandler.Load(); h != nil {
+		if sh, ok := (*h).(SeverityLogger); ok {
+			return sh.Severity()
+		}
+	}
+	// log everything by default
+	return Severity_Debug
+}
+
+var logHandler atomic.Pointer[Handler]
 
 // RegisterHandler registers a new handler as current log handler. Previous registered handler will be discarded.
 func RegisterHandler(handler Handler) {
 	if handler == nil {
 		panic("Log handler is nil")
 	}
-	logHandler.Set(handler)
-}
-
-type syncHandler struct {
-	sync.RWMutex
-	Handler
-}
-
-func (h *syncHandler) Handle(msg Message) {
-	h.RLock()
-	defer h.RUnlock()
-
-	if h.Handler != nil {
-		h.Handler.Handle(msg)
-	}
-}
-
-func (h *syncHandler) Set(handler Handler) {
-	h.Lock()
-	defer h.Unlock()
-
-	h.Handler = handler
+	logHandler.Store(&handler)
 }

common/log/logger.go

@@ -68,6 +68,10 @@ func (l *serverityLogger) Handle(msg Message) {
 	}
 }
 
+func (l *serverityLogger) Severity() Severity {
+	return l.logLevel
+}
+
 func (l *generalLogger) run() {
 	defer l.access.Signal()
 

common/mux/client.go

@@ -38,7 +38,7 @@ func (m *ClientManager) Dispatch(ctx context.Context, link *transport.Link) erro
 		}
 	}
 
-	return errors.New("unable to find an available mux client").AtWarning()
+	return errors.New("unable to find an available mux client")
 }
 
 type WorkerPicker interface {

common/mux/frame.go

@@ -117,7 +117,7 @@ func (f *FrameMetadata) Unmarshal(reader io.Reader, readSourceAndLocal bool) err
 		return err
 	}
 	if metaLen > 512 {
-		return errors.New("invalid metalen ", metaLen).AtError()
+		return errors.New("invalid metalen ", metaLen)
 	}
 
 	b := buf.New()

common/mux/server.go

@@ -351,7 +351,7 @@ func (w *ServerWorker) handleFrame(ctx context.Context, reader *buf.BufferedRead
 		err = w.handleStatusKeep(&meta, reader)
 	default:
 		status := meta.SessionStatus
-		return errors.New("unknown status: ", status).AtError()
+		return errors.New("unknown status: ", status)
 	}
 
 	if err != nil {

common/net/packet.go

@@ -0,0 +1,20 @@
+package net
+
+// PacketConnWrapper wraps a PacketConn into a Conn with a fixed destination address.
+type PacketConnWrapper struct {
+	PacketConn
+	Dest Addr
+}
+
+func (c *PacketConnWrapper) Read(p []byte) (int, error) {
+	n, _, err := c.PacketConn.ReadFrom(p)
+	return n, err
+}
+
+func (c *PacketConnWrapper) Write(p []byte) (int, error) {
+	return c.PacketConn.WriteTo(p, c.Dest)
+}
+
+func (c *PacketConnWrapper) RemoteAddr() Addr {
+	return c.Dest
+}

common/protocol/user.go

@@ -7,7 +7,7 @@ import (
 
 func (u *User) GetTypedAccount() (Account, error) {
 	if u.GetAccount() == nil {
-		return nil, errors.New("Account is missing").AtWarning()
+		return nil, errors.New("Account is missing")
 	}
 
 	rawAccount, err := u.Account.GetInstance()

common/singbridge/destination.go

@@ -1,53 +0,0 @@
-package singbridge
-
-import (
-	M "github.com/sagernet/sing/common/metadata"
-	N "github.com/sagernet/sing/common/network"
-	"github.com/xtls/xray-core/common/errors"
-	"github.com/xtls/xray-core/common/net"
-)
-
-func ToNetwork(network string) net.Network {
-	switch N.NetworkName(network) {
-	case N.NetworkTCP:
-		return net.Network_TCP
-	case N.NetworkUDP:
-		return net.Network_UDP
-	default:
-		return net.Network_Unknown
-	}
-}
-
-func ToDestination(socksaddr M.Socksaddr, network net.Network) (net.Destination, error) {
-	// IsFqdn() implicitly checks if the domain name is valid
-	if socksaddr.IsFqdn() {
-		return net.Destination{
-			Network: network,
-			Address: net.DomainAddress(socksaddr.Fqdn),
-			Port:    net.Port(socksaddr.Port),
-		}, nil
-	}
-
-	// IsIP() implicitly checks if the IP address is valid
-	if socksaddr.IsIP() {
-		return net.Destination{
-			Network: network,
-			Address: net.IPAddress(socksaddr.Addr.AsSlice()),
-			Port:    net.Port(socksaddr.Port),
-		}, nil
-	}
-
-	return net.Destination{}, errors.New("invalid socks address: ", socksaddr)
-}
-
-func ToSocksaddr(destination net.Destination) M.Socksaddr {
-	var addr M.Socksaddr
-	switch destination.Address.Family() {
-	case net.AddressFamilyDomain:
-		addr.Fqdn = destination.Address.Domain()
-	default:
-		addr.Addr = M.AddrFromIP(destination.Address.IP())
-	}
-	addr.Port = uint16(destination.Port)
-	return addr
-}

common/singbridge/dialer.go

@@ -1,72 +0,0 @@
-package singbridge
-
-import (
-	"context"
-	"os"
-
-	M "github.com/sagernet/sing/common/metadata"
-	N "github.com/sagernet/sing/common/network"
-	"github.com/xtls/xray-core/common/net"
-	"github.com/xtls/xray-core/common/net/cnc"
-	"github.com/xtls/xray-core/common/session"
-	"github.com/xtls/xray-core/proxy"
-	"github.com/xtls/xray-core/transport"
-	"github.com/xtls/xray-core/transport/internet"
-	"github.com/xtls/xray-core/transport/pipe"
-)
-
-var _ N.Dialer = (*XrayDialer)(nil)
-
-type XrayDialer struct {
-	internet.Dialer
-}
-
-func NewDialer(dialer internet.Dialer) *XrayDialer {
-	return &XrayDialer{dialer}
-}
-
-func (d *XrayDialer) DialContext(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
-	dest, err := ToDestination(destination, ToNetwork(network))
-	if err != nil {
-		return nil, err
-	}
-	return d.Dialer.Dial(ctx, dest)
-}
-
-func (d *XrayDialer) ListenPacket(ctx context.Context, destination M.Socksaddr) (net.PacketConn, error) {
-	return nil, os.ErrInvalid
-}
-
-type XrayOutboundDialer struct {
-	outbound proxy.Outbound
-	dialer   internet.Dialer
-}
-
-func NewOutboundDialer(outbound proxy.Outbound, dialer internet.Dialer) *XrayOutboundDialer {
-	return &XrayOutboundDialer{outbound, dialer}
-}
-
-func (d *XrayOutboundDialer) DialContext(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
-	dest, err := ToDestination(destination, ToNetwork(network))
-	if err != nil {
-		return nil, err
-	}
-	outbounds := session.OutboundsFromContext(ctx)
-	if len(outbounds) == 0 {
-		outbounds = []*session.Outbound{{}}
-		ctx = session.ContextWithOutbounds(ctx, outbounds)
-	}
-	ob := outbounds[len(outbounds)-1]
-	ob.Target = dest
-
-	opts := []pipe.Option{pipe.WithSizeLimit(64 * 1024)}
-	uplinkReader, uplinkWriter := pipe.New(opts...)
-	downlinkReader, downlinkWriter := pipe.New(opts...)
-	conn := cnc.NewConnection(cnc.ConnectionInputMulti(downlinkWriter), cnc.ConnectionOutputMulti(uplinkReader))
-	go d.outbound.Process(ctx, &transport.Link{Reader: downlinkReader, Writer: uplinkWriter}, d.dialer)
-	return conn, nil
-}
-
-func (d *XrayOutboundDialer) ListenPacket(ctx context.Context, destination M.Socksaddr) (net.PacketConn, error) {
-	return nil, os.ErrInvalid
-}

common/singbridge/error.go

@@ -1,10 +0,0 @@
-package singbridge
-
-import E "github.com/sagernet/sing/common/exceptions"
-
-func ReturnError(err error) error {
-	if E.IsClosedOrCanceled(err) {
-		return nil
-	}
-	return err
-}

common/singbridge/handler.go

@@ -1,58 +0,0 @@
-package singbridge
-
-import (
-	"context"
-	"io"
-
-	M "github.com/sagernet/sing/common/metadata"
-	N "github.com/sagernet/sing/common/network"
-	"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/features/routing"
-	"github.com/xtls/xray-core/transport"
-)
-
-var (
-	_ N.TCPConnectionHandler = (*Dispatcher)(nil)
-	_ N.UDPConnectionHandler = (*Dispatcher)(nil)
-)
-
-type Dispatcher struct {
-	upstream     routing.Dispatcher
-	newErrorFunc func(values ...any) *errors.Error
-}
-
-func NewDispatcher(dispatcher routing.Dispatcher, newErrorFunc func(values ...any) *errors.Error) *Dispatcher {
-	return &Dispatcher{
-		upstream:     dispatcher,
-		newErrorFunc: newErrorFunc,
-	}
-}
-
-func (d *Dispatcher) NewConnection(ctx context.Context, conn net.Conn, metadata M.Metadata) error {
-	dest, err := ToDestination(metadata.Destination, net.Network_TCP)
-	if err != nil {
-		return err
-	}
-	xConn := NewConn(conn)
-	return d.upstream.DispatchLink(ctx, dest, &transport.Link{
-		Reader: xConn,
-		Writer: xConn,
-	})
-}
-
-func (d *Dispatcher) NewPacketConnection(ctx context.Context, conn N.PacketConn, metadata M.Metadata) error {
-	dest, err := ToDestination(metadata.Destination, net.Network_UDP)
-	if err != nil {
-		return err
-	}
-	return d.upstream.DispatchLink(ctx, dest, &transport.Link{
-		Reader: buf.NewPacketReader(conn.(io.Reader)),
-		Writer: buf.NewWriter(conn.(io.Writer)),
-	})
-}
-
-func (d *Dispatcher) NewError(ctx context.Context, err error) {
-	errors.LogInfo(ctx, err.Error())
-}

common/singbridge/logger.go

@@ -1,70 +0,0 @@
-package singbridge
-
-import (
-	"context"
-
-	"github.com/sagernet/sing/common/logger"
-	"github.com/xtls/xray-core/common/errors"
-)
-
-var _ logger.ContextLogger = (*XrayLogger)(nil)
-
-type XrayLogger struct {
-	newError func(values ...any) *errors.Error
-}
-
-func NewLogger(newErrorFunc func(values ...any) *errors.Error) *XrayLogger {
-	return &XrayLogger{
-		newErrorFunc,
-	}
-}
-
-func (l *XrayLogger) Trace(args ...any) {
-}
-
-func (l *XrayLogger) Debug(args ...any) {
-	errors.LogDebug(context.Background(), args...)
-}
-
-func (l *XrayLogger) Info(args ...any) {
-	errors.LogInfo(context.Background(), args...)
-}
-
-func (l *XrayLogger) Warn(args ...any) {
-	errors.LogWarning(context.Background(), args...)
-}
-
-func (l *XrayLogger) Error(args ...any) {
-	errors.LogError(context.Background(), args...)
-}
-
-func (l *XrayLogger) Fatal(args ...any) {
-}
-
-func (l *XrayLogger) Panic(args ...any) {
-}
-
-func (l *XrayLogger) TraceContext(ctx context.Context, args ...any) {
-}
-
-func (l *XrayLogger) DebugContext(ctx context.Context, args ...any) {
-	errors.LogDebug(ctx, args...)
-}
-
-func (l *XrayLogger) InfoContext(ctx context.Context, args ...any) {
-	errors.LogInfo(ctx, args...)
-}
-
-func (l *XrayLogger) WarnContext(ctx context.Context, args ...any) {
-	errors.LogWarning(ctx, args...)
-}
-
-func (l *XrayLogger) ErrorContext(ctx context.Context, args ...any) {
-	errors.LogError(ctx, args...)
-}
-
-func (l *XrayLogger) FatalContext(ctx context.Context, args ...any) {
-}
-
-func (l *XrayLogger) PanicContext(ctx context.Context, args ...any) {
-}

common/singbridge/packet.go

@@ -1,107 +0,0 @@
-package singbridge
-
-import (
-	"context"
-	"time"
-
-	B "github.com/sagernet/sing/common/buf"
-	"github.com/sagernet/sing/common/bufio"
-	M "github.com/sagernet/sing/common/metadata"
-	"github.com/xtls/xray-core/common"
-	"github.com/xtls/xray-core/common/buf"
-	"github.com/xtls/xray-core/common/net"
-	"github.com/xtls/xray-core/common/signal"
-	"github.com/xtls/xray-core/transport"
-)
-
-func CopyPacketConn(ctx context.Context, inboundConn net.Conn, link *transport.Link, destination net.Destination, serverConn net.PacketConn) error {
-	cancel := func() {
-		common.Interrupt(link.Reader)
-		common.Interrupt(serverConn)
-	}
-	conn := &PacketConnWrapper{
-		Reader: link.Reader,
-		Writer: link.Writer,
-		Dest:   destination,
-		Conn:   inboundConn,
-		T:      signal.CancelAfterInactivity(ctx, cancel, 300*time.Second),
-	}
-	return ReturnError(bufio.CopyPacketConn(ctx, conn, bufio.NewPacketConn(serverConn)))
-}
-
-type PacketConnWrapper struct {
-	buf.Reader
-	buf.Writer
-	net.Conn
-	Dest   net.Destination
-	cached buf.MultiBuffer
-
-	// A simple patch to avoid goroutine leak since sing infra cannot awake read block by write err
-	T *signal.ActivityTimer
-}
-
-func (w *PacketConnWrapper) ReadPacket(buffer *B.Buffer) (addr M.Socksaddr, err error) {
-	w.T.Update()
-	defer func() {
-		if err != nil {
-			// uplinkonly
-			w.T.SetTimeout(2 * time.Second)
-		}
-	}()
-	if w.cached != nil {
-		mb, bb := buf.SplitFirst(w.cached)
-		if bb == nil {
-			w.cached = nil
-		} else {
-			buffer.Write(bb.Bytes())
-			w.cached = mb
-			var destination net.Destination
-			if bb.UDP != nil {
-				destination = *bb.UDP
-			} else {
-				destination = w.Dest
-			}
-			bb.Release()
-			return ToSocksaddr(destination), nil
-		}
-	}
-	mb, err := w.ReadMultiBuffer()
-	nb, bb := buf.SplitFirst(mb)
-	if bb == nil {
-		return M.Socksaddr{}, nil
-	} else {
-		buffer.Write(bb.Bytes())
-		w.cached = nb
-		var destination net.Destination
-		if bb.UDP != nil {
-			destination = *bb.UDP
-		} else {
-			destination = w.Dest
-		}
-		bb.Release()
-		return ToSocksaddr(destination), nil
-	}
-}
-
-func (w *PacketConnWrapper) WritePacket(buffer *B.Buffer, destination M.Socksaddr) (err error) {
-	w.T.Update()
-	defer func() {
-		if err != nil {
-			// downlinkonly
-			w.T.SetTimeout(5 * time.Second)
-		}
-	}()
-	endpoint, err := ToDestination(destination, net.Network_UDP)
-	if err != nil {
-		return err
-	}
-	vBuf := buf.New()
-	vBuf.Write(buffer.Bytes())
-	vBuf.UDP = &endpoint
-	return w.WriteMultiBuffer(buf.MultiBuffer{vBuf})
-}
-
-func (w *PacketConnWrapper) Close() error {
-	buf.ReleaseMulti(w.cached)
-	return nil
-}

common/singbridge/pipe.go

@@ -1,81 +0,0 @@
-package singbridge
-
-import (
-	"context"
-	"io"
-	"net"
-	"time"
-
-	"github.com/sagernet/sing/common/bufio"
-	"github.com/xtls/xray-core/common"
-	"github.com/xtls/xray-core/common/buf"
-	"github.com/xtls/xray-core/common/signal"
-	"github.com/xtls/xray-core/transport"
-)
-
-func CopyConn(ctx context.Context, inboundConn net.Conn, link *transport.Link, serverConn net.Conn) error {
-	conn := &PipeConnWrapper{
-		W:    link.Writer,
-		Conn: inboundConn,
-	}
-	if ir, ok := link.Reader.(io.Reader); ok {
-		conn.R = ir
-	} else {
-		conn.R = &buf.BufferedReader{Reader: link.Reader}
-	}
-	cancel := func() {
-		common.Interrupt(link.Reader)
-		common.Interrupt(serverConn)
-	}
-	conn.T = signal.CancelAfterInactivity(ctx, cancel, 300*time.Second)
-	return ReturnError(bufio.CopyConn(ctx, conn, serverConn))
-}
-
-type PipeConnWrapper struct {
-	R io.Reader
-	W buf.Writer
-	net.Conn
-
-	// A simple patch to avoid goroutine leak since sing infra cannot awake read block by write err
-	T *signal.ActivityTimer
-}
-
-func (w *PipeConnWrapper) Close() error {
-	return nil
-}
-
-func (w *PipeConnWrapper) Read(b []byte) (n int, err error) {
-	w.T.Update()
-	n, err = w.R.Read(b)
-	if err != nil {
-		// uplinkonly
-		w.T.SetTimeout(2 * time.Second)
-	}
-	return
-}
-
-func (w *PipeConnWrapper) Write(p []byte) (n int, err error) {
-	w.T.Update()
-	n = len(p)
-	var mb buf.MultiBuffer
-	pLen := len(p)
-	for pLen > 0 {
-		buffer := buf.New()
-		if pLen > buf.Size {
-			_, err = buffer.Write(p[:buf.Size])
-			p = p[buf.Size:]
-		} else {
-			buffer.Write(p)
-		}
-		pLen -= int(buffer.Len())
-		mb = append(mb, buffer)
-	}
-	err = w.W.WriteMultiBuffer(mb)
-	if err != nil {
-		n = 0
-		buf.ReleaseMulti(mb)
-		// downlinkonly
-		w.T.SetTimeout(5 * time.Second)
-	}
-	return
-}

common/singbridge/reader.go

@@ -1,66 +0,0 @@
-package singbridge
-
-import (
-	"time"
-
-	"github.com/sagernet/sing/common"
-	"github.com/sagernet/sing/common/bufio"
-	N "github.com/sagernet/sing/common/network"
-	"github.com/xtls/xray-core/common/buf"
-	"github.com/xtls/xray-core/common/net"
-)
-
-var (
-	_ buf.Reader        = (*Conn)(nil)
-	_ buf.TimeoutReader = (*Conn)(nil)
-	_ buf.Writer        = (*Conn)(nil)
-)
-
-type Conn struct {
-	net.Conn
-	writer N.VectorisedWriter
-}
-
-func NewConn(conn net.Conn) *Conn {
-	writer, _ := bufio.CreateVectorisedWriter(conn)
-	return &Conn{
-		Conn:   conn,
-		writer: writer,
-	}
-}
-
-func (c *Conn) ReadMultiBuffer() (buf.MultiBuffer, error) {
-	buffer, err := buf.ReadBuffer(c.Conn)
-	if err != nil {
-		return nil, err
-	}
-	return buf.MultiBuffer{buffer}, nil
-}
-
-func (c *Conn) ReadMultiBufferTimeout(duration time.Duration) (buf.MultiBuffer, error) {
-	err := c.SetReadDeadline(time.Now().Add(duration))
-	if err != nil {
-		return nil, err
-	}
-	defer c.SetReadDeadline(time.Time{})
-	return c.ReadMultiBuffer()
-}
-
-func (c *Conn) WriteMultiBuffer(bufferList buf.MultiBuffer) error {
-	defer buf.ReleaseMulti(bufferList)
-	if c.writer != nil {
-		bytesList := make([][]byte, len(bufferList))
-		for i, buffer := range bufferList {
-			bytesList[i] = buffer.Bytes()
-		}
-		return common.Error(bufio.WriteVectorised(c.writer, bytesList))
-	}
-	// Since this conn is only used by tun, we don't force buffer writes to merge.
-	for _, buffer := range bufferList {
-		_, err := c.Conn.Write(buffer.Bytes())
-		if err != nil {
-			return err
-		}
-	}
-	return nil
-}

common/type.go

@@ -16,7 +16,7 @@ var typeCreatorRegistry = make(map[reflect.Type]ConfigCreator)
 func RegisterConfig(config interface{}, configCreator ConfigCreator) error {
 	configType := reflect.TypeOf(config)
 	if _, found := typeCreatorRegistry[configType]; found {
-		return errors.New(configType.Name() + " is already registered").AtError()
+		return errors.New(configType.Name() + " is already registered")
 	}
 	typeCreatorRegistry[configType] = configCreator
 	return nil
@@ -27,7 +27,7 @@ func CreateObject(ctx context.Context, config interface{}) (interface{}, error)
 	configType := reflect.TypeOf(config)
 	creator, found := typeCreatorRegistry[configType]
 	if !found {
-		return nil, errors.New(configType.String() + " is not registered").AtError()
+		return nil, errors.New(configType.String() + " is not registered")
 	}
 	return creator(ctx, config)
 }

core/config.go

@@ -125,7 +125,7 @@ func LoadConfig(formatName string, input interface{}) (*Config, error) {
 			}
 
 			if f == "" {
-				return nil, errors.New("Failed to get format of ", file).AtWarning()
+				return nil, errors.New("Failed to get format of ", file)
 			}
 
 			if f == "protobuf" {
@@ -142,7 +142,7 @@ func LoadConfig(formatName string, input interface{}) (*Config, error) {
 			if len(v) == 1 {
 				return configLoaderByName["protobuf"].Loader(v)
 			} else {
-				return nil, errors.New("Only one protobuf config file is allowed").AtWarning()
+				return nil, errors.New("Only one protobuf config file is allowed")
 			}
 		}
 
@@ -152,11 +152,11 @@ func LoadConfig(formatName string, input interface{}) (*Config, error) {
 		if f, found := configLoaderByName[formatName]; found {
 			return f.Loader(v)
 		} else {
-			return nil, errors.New("Unable to load config in", formatName).AtWarning()
+			return nil, errors.New("Unable to load config in", formatName)
 		}
 	}
 
-	return nil, errors.New("Unable to load config").AtWarning()
+	return nil, errors.New("Unable to load config")
 }
 
 func loadProtobufConfig(data []byte) (*Config, error) {

core/core.go

@@ -19,8 +19,8 @@ import (
 
 var (
 	Version_x byte = 26
-	Version_y byte = 7
-	Version_z byte = 28
+	Version_y byte = 9
+	Version_z byte = 9
 )
 
 var (

features/dns/fakedns.go

@@ -13,7 +13,7 @@ type FakeDNSEngine interface {
 
 var (
 	FakeIPv4Pool = "198.18.0.0/15"
-	FakeIPv6Pool = "fc00::/18"
+	FakeIPv6Pool = "2001:2::/48"
 )
 
 type FakeDNSEngineRev0 interface {

go.mod

@@ -1,6 +1,6 @@
 module github.com/xtls/xray-core
 
-go 1.26
+go 1.27
 
 require (
 	github.com/apernet/quic-go v0.61.1-0.20260806010916-184d081eef3e
@@ -18,25 +18,24 @@ require (
 	github.com/pires/go-proxyproto v0.15.0
 	github.com/refraction-networking/utls v1.8.3-0.20260301010127-aa6edf4b11af
 	github.com/robfig/cron/v3 v3.0.1
-	github.com/sagernet/sing v0.5.1
-	github.com/sagernet/sing-shadowsocks v0.2.7
 	github.com/stretchr/testify v1.12.1
 	github.com/vishvananda/netlink v1.3.1
 	github.com/xtls/reality v0.0.0-20260908062103-8cdf7bf9c7f0
 	go4.org/netipx v0.0.0-20231129151722-fdeea329fbba
-	golang.org/x/crypto v0.55.0
+	golang.org/x/crypto v0.57.0
 	golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842
-	golang.org/x/net v0.58.0
-	golang.org/x/sync v0.22.0
-	golang.org/x/sys v0.47.0
+	golang.org/x/net v0.59.0
+	golang.org/x/sync v0.23.0
+	golang.org/x/sys v0.48.0
 	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2
 	golang.zx2c4.com/wireguard v0.0.0-20250521234502-f333402bd9cb
-	golang.zx2c4.com/wireguard/windows v1.0.1
-	google.golang.org/grpc v1.83.2
+	golang.zx2c4.com/wireguard/windows v1.1.1
+	google.golang.org/grpc v1.84.0
 	google.golang.org/protobuf v1.36.12
 	gvisor.dev/gvisor v0.0.0-20260122175437-89a5d21be8f0
 	h12.io/socks v1.0.3
 	lukechampine.com/blake3 v1.4.1
+	mvdan.cc/gofumpt v0.12.0
 )
 
 require (
@@ -48,7 +47,6 @@ require (
 	github.com/juju/ratelimit v1.0.2 // indirect
 	github.com/klauspost/compress v1.17.4 // indirect
 	github.com/koron/go-ssdp v0.0.4 // indirect
-	github.com/kr/text v0.2.0 // indirect
 	github.com/libp2p/go-netroute v0.2.1 // indirect
 	github.com/pion/dtls/v3 v3.1.5 // indirect
 	github.com/pion/logging v0.2.4 // indirect
@@ -57,8 +55,9 @@ require (
 	github.com/vishvananda/netns v0.0.5 // indirect
 	github.com/wlynxg/anet v0.0.5 // indirect
 	go.yaml.in/yaml/v3 v3.0.5 // indirect
-	golang.org/x/text v0.41.0 // indirect
+	golang.org/x/text v0.42.0 // indirect
 	golang.org/x/time v0.14.0 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa // indirect
+	golang.org/x/tools v0.49.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20260706201446-f0a921348800 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )

go.sum

@@ -2,17 +2,12 @@ github.com/andybalholm/brotli v1.0.6 h1:Yf9fFpf49Zrxb9NlQaluyE92/+X7UVHlhMNJN2sx
 github.com/andybalholm/brotli v1.0.6/go.mod h1:fO7iG3H7G2nSZ7m0zPUDn85XEX2GTukHGRSepvi9Eig=
 github.com/apernet/quic-go v0.61.1-0.20260806010916-184d081eef3e h1:5mgtR5gwIgBKMiGI1QdXldZZ+SNor06Nbu1wCBulQBg=
 github.com/apernet/quic-go v0.61.1-0.20260806010916-184d081eef3e/go.mod h1:x7qxEvX6MCVtDuBKHj3E+88+BtrbEMuAL5qGUKItjW8=
-github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
-github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/cloudflare/circl v1.6.5 h1:O64F26HEqNhznd/hrC5KZXVKYuKM2rx4deZDTc4ihQA=
 github.com/cloudflare/circl v1.6.5/go.mod h1:h5LNyxAc5nTue9DS5jT+48en2PSDYt3zdGnz5OstK6c=
-github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/ghodss/yaml v1.0.1-0.20220118164431-d8423dcdf344 h1:Arcl6UOIS/kgO2nW3A65HN+7CMjSDP/gofXL4CZt1V4=
 github.com/ghodss/yaml v1.0.1-0.20220118164431-d8423dcdf344/go.mod h1:GIjDIg/heH5DOkXY3YJ/wNhfHsQHoXGjl8G8amsYQ1I=
-github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
-github.com/go-logr/logr v1.4.3/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
-github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
-github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
+github.com/go-quicktest/qt v1.102.0 h1:HSQxCeh5YZH3EL3W39ixjtyaEhcWSXQHtHnMBzSs474=
+github.com/go-quicktest/qt v1.102.0/go.mod h1:p4lGIVX+8Wa6ZPNDvqcxq36XpUDLh42FLetFU7odllI=
 github.com/golang/mock v1.7.0-rc.1 h1:YojYx61/OLFsiv6Rw1Z96LpldJIy31o+UHmwAUMJ6/U=
 github.com/golang/mock v1.7.0-rc.1/go.mod h1:s42URUywIqd+OcERslBJvOjepvNymP31m3q8d/GkuRs=
 github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
@@ -73,12 +68,8 @@ github.com/refraction-networking/utls v1.8.3-0.20260301010127-aa6edf4b11af h1:er
 github.com/refraction-networking/utls v1.8.3-0.20260301010127-aa6edf4b11af/go.mod h1:jkSOEkLqn+S/jtpEHPOsVv/4V4EVnelwbMQl4vCWXAM=
 github.com/robfig/cron/v3 v3.0.1 h1:WdRxkvbJztn8LMz/QEvLN5sBU+xKpSqwwUO1Pjr4qDs=
 github.com/robfig/cron/v3 v3.0.1/go.mod h1:eQICP3HwyT7UooqI/z+Ov+PtYAWygg1TEWWzGIFLtro=
-github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
-github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
-github.com/sagernet/sing v0.5.1 h1:mhL/MZVq0TjuvHcpYcFtmSD1BFOxZ/+8ofbNZcg1k1Y=
-github.com/sagernet/sing v0.5.1/go.mod h1:ARkL0gM13/Iv5VCZmci/NuoOlePoIsW0m7BWfln/Hak=
-github.com/sagernet/sing-shadowsocks v0.2.7 h1:zaopR1tbHEw5Nk6FAkM05wCslV6ahVegEZaKMv9ipx8=
-github.com/sagernet/sing-shadowsocks v0.2.7/go.mod h1:0rIKJZBR65Qi0zwdKezt4s57y/Tl1ofkaq6NlkzVuyE=
+github.com/rogpeppe/go-internal v1.16.0 h1:O9DK+vNMDVGLr2BeZqmpLeMjiMNkuXfcqntWbZV6S5g=
+github.com/rogpeppe/go-internal v1.16.0/go.mod h1:DrUVZyrJU+txYW5/1kwtXQSMFio52ZOxX7yM1VHvnxs=
 github.com/stretchr/testify v1.12.1 h1:EuwCh5fleGS7H32xRwO3wRGT7DxrDhLAT6FF8MpWDWE=
 github.com/stretchr/testify v1.12.1/go.mod h1:MDEgiDPPsNp5cuIrHPPCyornHKgEVbtFUmoNlxoYthg=
 github.com/vishvananda/netlink v1.3.1 h1:3AEMt62VKqz90r0tmNhog0r/PpWKmrEShJU0wJW6bV0=
@@ -90,18 +81,6 @@ github.com/wlynxg/anet v0.0.5/go.mod h1:eay5PRQr7fIVAMbTbchTnO9gG65Hg/uYGdc7mguH
 github.com/xtls/reality v0.0.0-20260908062103-8cdf7bf9c7f0 h1:rb+fKQFhz+5I2PPuQsNYxI5mUU840XWYtRF0ZBjvkws=
 github.com/xtls/reality v0.0.0-20260908062103-8cdf7bf9c7f0/go.mod h1:DsJblcWDGt76+FVqBVwbwRhxyyNJsGV48gJLch0OOWI=
 github.com/yuin/goldmark v1.4.1/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
-go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
-go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
-go.opentelemetry.io/otel v1.44.0 h1:JjwHmHpA4iZ3wBxluu2fbbE7j4kqlE8jXyAyPXH7HqU=
-go.opentelemetry.io/otel v1.44.0/go.mod h1:BMgjTHL9WPRlRjL2oZCBTL4whCGtXch2H4BhOPIAyYc=
-go.opentelemetry.io/otel/metric v1.44.0 h1:1w0gILTcHdr3YI+ixLyjemwrVnsMURbTZFrSYCdDdmc=
-go.opentelemetry.io/otel/metric v1.44.0/go.mod h1:8O7hanEPBNgEMmybD3s2VBKcgWOCsA6tzHBPODAiquo=
-go.opentelemetry.io/otel/sdk v1.44.0 h1:nHYwb9lK+fJPU/dnT6s7W7Z8itMWyqrnVfbheVYrZ58=
-go.opentelemetry.io/otel/sdk v1.44.0/go.mod h1:Osuydd3Se74nqjAKxid74N5eC+jfEqfTegHRnq58oK0=
-go.opentelemetry.io/otel/sdk/metric v1.44.0 h1:3LlKgI+VjbVsjNRFZJZAJ30WjXC5VkNRks6si09iEfI=
-go.opentelemetry.io/otel/sdk/metric v1.44.0/go.mod h1:5B5pMARnXxKhltooO4xUuCBorl65a4EpnTalObqOigA=
-go.opentelemetry.io/otel/trace v1.44.0 h1:jxF5CsGYCe74MCRx2X4g7WsY/VBKRqqpNvXlX/6gtIk=
-go.opentelemetry.io/otel/trace v1.44.0/go.mod h1:oLl1jrMQAVo6v3GAggN+1VH9VIz9iUSvW53sW1Q8PIE=
 go.uber.org/mock v0.5.2 h1:LbtPTcP8A5k9WPXj54PPPbjcI4Y6lhyOZXn+VS7wNko=
 go.uber.org/mock v0.5.2/go.mod h1:wLlUxC2vVTPTaE3UD51E0BGOAElKrILxhVSDYQLld5o=
 go.yaml.in/yaml/v3 v3.0.5 h1:N6y/pJk8buWs9NY5ERU2HSMfm+IuD/OtfdAnq6kESPw=
@@ -110,8 +89,8 @@ go4.org/netipx v0.0.0-20231129151722-fdeea329fbba h1:0b9z3AuHCjxk0x/opv64kcgZLBs
 go4.org/netipx v0.0.0-20231129151722-fdeea329fbba/go.mod h1:PLyyIXexvUFg3Owu6p/WfdlivPbZJsZdgWZlrGope/Y=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/crypto v0.55.0 h1:+KWHjbgOaAQ66dh/YlkZKHlz9ZUlq61AFirAR9ntP8M=
-golang.org/x/crypto v0.55.0/go.mod h1:uq0V9dE/fzQuJtbnL+2EhWOE63vo164FY8xqEnV9xis=
+golang.org/x/crypto v0.57.0 h1:3ZVCjf8Ggz7zneR/EHRVx68Ctf+2pmIMP2UFhh9cC6M=
+golang.org/x/crypto v0.57.0/go.mod h1:Fdz0i5U6CoizGwLda9DttjSk6qlZo25zYNtR+ycvuZA=
 golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842 h1:vr/HnozRka3pE4EsMEg1lgkXJkTFJCVUX+S/ZT6wYzM=
 golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842/go.mod h1:XtvwrStGgqGPLc4cjQfWqZHG1YFdYs6swckp8vpsjnc=
 golang.org/x/lint v0.0.0-20200302205851-738671d3881b/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
@@ -120,12 +99,12 @@ golang.org/x/mod v0.5.1/go.mod h1:5OXOZSfqPIIbmVBIIKWRFfZjPR0E5r58TLhUjH0a2Ro=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20211015210444-4f30a5c0130f/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/net v0.58.0 h1:ynWG7rqYi4ccpTEuPZ2QGWHktVEM9DMCj9yzDE0Q7To=
-golang.org/x/net v0.58.0/go.mod h1:YwCddHnFlT7eLQqVprV19OnhLGtc5xOKgE0RyqgfWAU=
+golang.org/x/net v0.59.0 h1:5zfYln+w5XCxwrnMMJPufRgNoXEaGxl0wo5GqPXyues=
+golang.org/x/net v0.59.0/go.mod h1:2DA/G1UfVbCpQPeWTmMPGY7Cs2PkBkwu743bVX5PIVg=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.22.0 h1:SZjpbeLmrCk4xhRSZFNZW5gFUeCeFgjekvI/+gfScek=
-golang.org/x/sync v0.22.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
+golang.org/x/sync v0.23.0 h1:KameEIfc1IkluZyXWLn39Wd4tURc6GbCiISGiZm2bQk=
+golang.org/x/sync v0.23.0/go.mod h1:sUUOizhqBxiL6pEWpqNLUiaJn1ShEbZ6BBqskPbjZm0=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -133,20 +112,22 @@ golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20211019181941-9d821ace8654/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.10.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.47.0 h1:o7XGOvZQCADBQQ4Y7VNq2dRWQR7JmOUW8Kxx4ZsNgWs=
-golang.org/x/sys v0.47.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+golang.org/x/sys v0.48.0 h1:bbX/i/6MgT9BVLM9RT1thmxL04yeTAhbEz4SyadbXoo=
+golang.org/x/sys v0.48.0/go.mod h1:hNLxWAXmnKAxqDtdwIYC4bM9oQPEecfsnNMuSxOs3og=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
-golang.org/x/text v0.41.0 h1:vz/seA0lnX87Othu2f/0L24RcgrXD9/YFTSuGjj3rH8=
-golang.org/x/text v0.41.0/go.mod h1:jvf1O8ajNzZqhSrQBPbutR/EB83Cc0CFrezNQIwbb5M=
+golang.org/x/text v0.42.0 h1:JbOZXgfeCPU9gacVtYliJqOhD+zhrEqK4LfdpmlUZqI=
+golang.org/x/text v0.42.0/go.mod h1:ojzP1Z+2QtioaF8DTtO8K5q7JWVVYwZKenzujK0Zd0E=
 golang.org/x/time v0.14.0 h1:MRx4UaLrDotUKUdCIqzPC48t1Y9hANFKIRpNx+Te8PI=
 golang.org/x/time v0.14.0/go.mod h1:eL/Oa2bBBK0TkX57Fyni+NgnyQQN4LitPmob2Hjnqw4=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20200130002326-2f3ba24bd6e7/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
 golang.org/x/tools v0.1.8/go.mod h1:nABZi5QlRsZVlzPpHl034qft6wpY4eDcsTt5AaioBiU=
+golang.org/x/tools v0.49.0 h1:3NI7VXzL9+1WZD52Dx2ttoPwD5DWrFGpl9mFZDlmisI=
+golang.org/x/tools v0.49.0/go.mod h1:SJNXV9DBKT0UbdttsQjbfJlAE/q+y36++zo3uL3N0Oo=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
@@ -154,14 +135,14 @@ golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2 h1:B82qJJgjvYKsXS9jeu
 golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2/go.mod h1:deeaetjYA+DHMHg+sMSMI58GrEteJUUzzw7en6TJQcI=
 golang.zx2c4.com/wireguard v0.0.0-20250521234502-f333402bd9cb h1:whnFRlWMcXI9d+ZbWg+4sHnLp52d5yiIPUxMBSt4X9A=
 golang.zx2c4.com/wireguard v0.0.0-20250521234502-f333402bd9cb/go.mod h1:rpwXGsirqLqN2L0JDJQlwOboGHmptD5ZD6T2VmcqhTw=
-golang.zx2c4.com/wireguard/windows v1.0.1 h1:eOxiDVbywPC+ZQqvdCK7x+ZwWXKbYv50TtH8ysFIbw8=
-golang.zx2c4.com/wireguard/windows v1.0.1/go.mod h1:+fbT3FFdX4zzYDLwJh5+HPEcNN/3HyNdzhNSVsQM+zs=
+golang.zx2c4.com/wireguard/windows v1.1.1 h1:8/H97U1v1PNDNcBsMZgU3KFuND9MQdTsU2NOwmCXArE=
+golang.zx2c4.com/wireguard/windows v1.1.1/go.mod h1:+fbT3FFdX4zzYDLwJh5+HPEcNN/3HyNdzhNSVsQM+zs=
 gonum.org/v1/gonum v0.17.0 h1:VbpOemQlsSMrYmn7T2OUvQ4dqxQXU+ouZFQsZOx50z4=
 gonum.org/v1/gonum v0.17.0/go.mod h1:El3tOrEuMpv2UdMrbNlKEh9vd86bmQ6vqIcDwxEOc1E=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa h1:mZHHdPZl0dbGHCflZgAq/Q468DWVFcU2whhB2KAo8fk=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
-google.golang.org/grpc v1.83.2 h1:EManeRomTObA0BU7I8vXgg/78uE5MJ9M8B39EX2WscU=
-google.golang.org/grpc v1.83.2/go.mod h1:YPI1hK3kDked6iHvgX3tR0y+nX/qpMFKhPgFsokw1S8=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20260706201446-f0a921348800 h1:qEHAMpSaUhtD0p3NbEEI83HwNGFxEwaSJ1G9PLnCBZE=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20260706201446-f0a921348800/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
+google.golang.org/grpc v1.84.0 h1:soMyaPJ8pAak5PIQ0DGBUir0XRo2fRoMqhNWMLlLxO0=
+google.golang.org/grpc v1.84.0/go.mod h1:ljCht0DrxQrXBDRTZp52Qxh3Ffk8CdYm2sj4O2QN2C0=
 google.golang.org/protobuf v1.36.12 h1:pJOKDDOyeXErUroCihFAd5LQuwXBSpVnKGrj5o/fwxc=
 google.golang.org/protobuf v1.36.12/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
@@ -176,3 +157,5 @@ h12.io/socks v1.0.3 h1:Ka3qaQewws4j4/eDQnOdpr4wXsC//dXtWvftlIcCQUo=
 h12.io/socks v1.0.3/go.mod h1:AIhxy1jOId/XCz9BO+EIgNL2rQiPTBNnOfnVnQ+3Eck=
 lukechampine.com/blake3 v1.4.1 h1:I3Smz7gso8w4/TunLKec6K2fn+kyKtDxr/xcQEN84Wg=
 lukechampine.com/blake3 v1.4.1/go.mod h1:QFosUxmjB8mnrWFSNwKmvxHpfY72bmD2tQ0kBMM3kwo=
+mvdan.cc/gofumpt v0.12.0 h1:1Lbudkz2kpM9Cjz2pL4M19u7q+GaEhCTNf7N9mfpcho=
+mvdan.cc/gofumpt v0.12.0/go.mod h1:SmBHHrljiZu/uoypeKup3rFzP6eoC9UwCp2iH5E3jZA=

infra/conf/http.go

@@ -97,7 +97,7 @@ func (v *HTTPClientConfig) Build() (proto.Message, error) {
 				user.Email = v.Email
 			} else {
 				if err := json.Unmarshal(rawUser, user); err != nil {
-					return nil, errors.New("failed to parse HTTP user").Base(err).AtError()
+					return nil, errors.New("failed to parse HTTP user").Base(err)
 				}
 			}
 			account := new(HTTPAccount)
@@ -106,7 +106,7 @@ func (v *HTTPClientConfig) Build() (proto.Message, error) {
 				account.Password = v.Password
 			} else {
 				if err := json.Unmarshal(rawUser, account); err != nil {
-					return nil, errors.New("failed to parse HTTP account").Base(err).AtError()
+					return nil, errors.New("failed to parse HTTP account").Base(err)
 				}
 			}
 			user.Account = serial.ToTypedMessage(account.Build())

infra/conf/lint.go

@@ -18,7 +18,7 @@ func RegisterConfigureFilePostProcessingStage(name string, stage ConfigureFilePo
 func PostProcessConfigureFile(conf *Config) error {
 	for k, v := range configureFilePostProcessingStages {
 		if err := v.Process(conf); err != nil {
-			return errors.New("Rejected by Postprocessing Stage ", k).AtError().Base(err)
+			return errors.New("Rejected by Postprocessing Stage ", k).Base(err)
 		}
 	}
 	return nil

infra/conf/loader.go

@@ -13,7 +13,7 @@ type ConfigCreatorCache map[string]ConfigCreator
 
 func (v ConfigCreatorCache) RegisterCreator(id string, creator ConfigCreator) error {
 	if _, found := v[id]; found {
-		return errors.New(id, " already registered.").AtError()
+		return errors.New(id, " already registered.")
 	}
 
 	v[id] = creator
@@ -61,7 +61,7 @@ func (v *JSONConfigLoader) Load(raw []byte) (interface{}, string, error) {
 	}
 	rawID, found := obj[v.idKey]
 	if !found {
-		return nil, "", errors.New(v.idKey, " not found in JSON context").AtError()
+		return nil, "", errors.New(v.idKey, " not found in JSON context")
 	}
 	var id string
 	if err := json.Unmarshal(rawID, &id); err != nil {

infra/conf/masque.go

@@ -0,0 +1,103 @@
+package conf
+
+import (
+	"net/netip"
+	"strings"
+
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/protocol"
+	"github.com/xtls/xray-core/common/serial"
+	"github.com/xtls/xray-core/proxy/masque"
+	"google.golang.org/protobuf/proto"
+)
+
+type MasqueClientConfig struct {
+	Address   *Address `json:"address"`
+	Port      uint16   `json:"port"`
+	RemoteDNS []string `json:"remoteDNS"`
+}
+
+func (c *MasqueClientConfig) Build() (proto.Message, error) {
+	if c.Address == nil {
+		return nil, errors.New(`MASQUE: "address" is not set`)
+	}
+	if c.Port == 0 {
+		return nil, errors.New(`MASQUE: "port" is not set`)
+	}
+	for _, s := range c.RemoteDNS {
+		if _, err := netip.ParseAddr(s); err != nil {
+			return nil, errors.New(`MASQUE: invalid "remoteDNS" `, s).Base(err)
+		}
+	}
+	return &masque.ClientConfig{
+		Server: &protocol.ServerEndpoint{
+			Address: c.Address.Build(),
+			Port:    uint32(c.Port),
+		},
+		RemoteDns: c.RemoteDNS,
+	}, nil
+}
+
+type MasqueUserConfig struct {
+	Pass  string `json:"pass"`
+	Level uint32 `json:"level"`
+	Email string `json:"email"`
+}
+
+type MasqueServerConfig struct {
+	Users   []*MasqueUserConfig `json:"users"`
+	Clients []*MasqueUserConfig `json:"clients"`
+	Address []string            `json:"address"`
+	MTU     uint32              `json:"mtu"`
+}
+
+func (c *MasqueServerConfig) Build() (proto.Message, error) {
+	if c.Clients != nil {
+		c.Users = c.Clients
+	}
+	config := &masque.ServerConfig{
+		Address: c.Address,
+		Mtu:     c.MTU,
+	}
+	emails := make(map[string]bool)
+	for _, user := range c.Users {
+		if user.Email == "" {
+			return nil, errors.New(`MASQUE: "email" is empty`)
+		}
+		if strings.Contains(user.Email, ":") {
+			return nil, errors.New(`MASQUE: invalid "email" `, user.Email)
+		}
+		if user.Pass == "" {
+			return nil, errors.New(`MASQUE: "pass" of `, user.Email, ` is empty`)
+		}
+		email := strings.ToLower(user.Email)
+		if emails[email] {
+			return nil, errors.New(`MASQUE: duplicate "email" `, user.Email)
+		}
+		emails[email] = true
+		config.Users = append(config.Users, &protocol.User{
+			Email:   user.Email,
+			Level:   user.Level,
+			Account: serial.ToTypedMessage(&masque.Account{Password: user.Pass}),
+		})
+	}
+	if len(c.Address) == 0 {
+		return nil, errors.New(`MASQUE: "address" is not set`)
+	}
+	var v4, v6 bool
+	for _, s := range c.Address {
+		prefix, err := netip.ParsePrefix(s)
+		if err != nil {
+			return nil, errors.New(`MASQUE: invalid "address" `, s).Base(err)
+		}
+		if prefix.Addr().Is4() && v4 || prefix.Addr().Is6() && v6 {
+			return nil, errors.New(`MASQUE: "address" takes at most one IPv4 and one IPv6 prefix`)
+		}
+		v4 = v4 || prefix.Addr().Is4()
+		v6 = v6 || prefix.Addr().Is6()
+	}
+	if c.MTU != 0 && (c.MTU < 1280 || c.MTU > 65535) {
+		return nil, errors.New(`MASQUE: "mtu" must be between 1280 and 65535`)
+	}
+	return config, nil
+}

infra/conf/masque_test.go

@@ -0,0 +1,188 @@
+package conf_test
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/xtls/xray-core/common/protocol"
+	"github.com/xtls/xray-core/common/serial"
+	. "github.com/xtls/xray-core/infra/conf"
+	masqueproxy "github.com/xtls/xray-core/proxy/masque"
+	"github.com/xtls/xray-core/transport/internet/masque"
+)
+
+func TestMasqueConfig(t *testing.T) {
+	creator := func() Buildable {
+		return new(MasqueConfig)
+	}
+
+	runMultiTestCase(t, []TestCase{
+		{
+			Input:  `{}`,
+			Parser: loadJSON(creator),
+			Output: &masque.Config{Path: "/.well-known/masque/ip/*/*/"},
+		},
+		{
+			Input: `{
+				"host": "example.com:8443",
+				"path": "/.well-known/masque/ip/{target}/{ipproto}/",
+				"headers": {"Authorization": "Basic dTpw"}
+			}`,
+			Parser: loadJSON(creator),
+			Output: &masque.Config{
+				Host:    "example.com:8443",
+				Path:    "/.well-known/masque/ip/*/*/",
+				Headers: map[string]string{"Authorization": "Basic dTpw"},
+			},
+		},
+		{
+			Input:  `{"path": "/masque/ip{?target,ipproto}"}`,
+			Parser: loadJSON(creator),
+			Output: &masque.Config{Path: "/masque/ip?target=*&ipproto=*"},
+		},
+		{
+			Input:  `{"user": "u", "pass": "p:q", "headers": {"X-Token": "a"}}`,
+			Parser: loadJSON(creator),
+			Output: &masque.Config{
+				Path:    "/.well-known/masque/ip/*/*/",
+				Headers: map[string]string{"Authorization": "Basic dTpwOnE=", "X-Token": "a"},
+			},
+		},
+	})
+
+	for _, input := range []string{
+		`{"path": "/masque/{target}/{ipproto}/{dns}"}`,
+		`{"path": "masque"}`,
+		`{"host": "example.com/path"}`,
+		`{"headers": {"host": "example.com"}}`,
+		`{"headers": {"Capsule-Protocol": "?0"}}`,
+		`{"headers": {"X Token": "a"}}`,
+		`{"headers": {"X-Token": "a\r\nb"}}`,
+		`{"user": "u:v", "pass": "p"}`,
+		`{"user": "u", "pass": "p", "headers": {"authorization": "Basic dTpw"}}`,
+	} {
+		if _, err := loadJSON(creator)(input); err == nil {
+			t.Errorf("expected an error for %s", input)
+		}
+	}
+}
+
+func TestMasqueOutboundConfig(t *testing.T) {
+	build := func(s string) error {
+		c := new(OutboundDetourConfig)
+		if err := json.Unmarshal([]byte(s), c); err != nil {
+			return err
+		}
+		_, err := c.Build()
+		return err
+	}
+
+	if err := build(`{
+		"protocol": "masque",
+		"settings": {"address": "example.com", "port": 443},
+		"streamSettings": {"network": "masque", "security": "tls"},
+		"mux": {"enabled": false, "concurrency": -1}
+	}`); err != nil {
+		t.Error(err)
+	}
+	for _, input := range []string{
+		`{"protocol": "masque", "settings": {"address": "example.com"}, "streamSettings": {"network": "masque", "security": "tls"}}`,
+		`{"protocol": "masque", "settings": {"address": "example.com", "port": 443}, "streamSettings": {"network": "masque", "security": "tls"}, "mux": {"enabled": true}}`,
+		`{"protocol": "masque", "settings": {"address": "example.com", "port": 443}, "streamSettings": {"network": "masque", "security": "tls"}, "mux": {"enabled": true, "concurrency": -1}}`,
+		`{"protocol": "freedom", "streamSettings": {"network": "masque", "security": "tls"}}`,
+	} {
+		if err := build(input); err == nil {
+			t.Errorf("expected an error for %s", input)
+		}
+	}
+}
+
+func TestMasqueServerConfig(t *testing.T) {
+	creator := func() Buildable {
+		return new(MasqueServerConfig)
+	}
+
+	runMultiTestCase(t, []TestCase{
+		{
+			Input: `{
+				"users": [{"email": "u@example.com", "pass": "p", "level": 1}],
+				"address": ["10.13.0.1/24", "fd13::1/64"],
+				"mtu": 1400
+			}`,
+			Parser: loadJSON(creator),
+			Output: &masqueproxy.ServerConfig{
+				Users: []*protocol.User{{
+					Email:   "u@example.com",
+					Level:   1,
+					Account: serial.ToTypedMessage(&masqueproxy.Account{Password: "p"}),
+				}},
+				Address: []string{"10.13.0.1/24", "fd13::1/64"},
+				Mtu:     1400,
+			},
+		},
+		{
+			Input:  `{"clients": [{"email": "u", "pass": "p:q"}], "address": ["10.13.0.1/24"]}`,
+			Parser: loadJSON(creator),
+			Output: &masqueproxy.ServerConfig{
+				Users: []*protocol.User{{
+					Email:   "u",
+					Account: serial.ToTypedMessage(&masqueproxy.Account{Password: "p:q"}),
+				}},
+				Address: []string{"10.13.0.1/24"},
+			},
+		},
+		{
+			Input:  `{"address": ["10.13.0.1/24"]}`,
+			Parser: loadJSON(creator),
+			Output: &masqueproxy.ServerConfig{
+				Address: []string{"10.13.0.1/24"},
+			},
+		},
+	})
+
+	for _, input := range []string{
+		`{"users": [{"email": "u:v", "pass": "p"}], "address": ["10.13.0.1/24"]}`,
+		`{"users": [{"email": "", "pass": "p"}], "address": ["10.13.0.1/24"]}`,
+		`{"users": [{"pass": "p"}], "address": ["10.13.0.1/24"]}`,
+		`{"users": [{"email": "u", "pass": ""}], "address": ["10.13.0.1/24"]}`,
+		`{"users": [{"email": "u", "pass": "p"}, {"email": "U", "pass": "q"}], "address": ["10.13.0.1/24"]}`,
+		`{"users": [{"email": "u", "pass": "p"}]}`,
+		`{"users": [{"email": "u", "pass": "p"}], "address": ["10.13.0.1"]}`,
+		`{"users": [{"email": "u", "pass": "p"}], "address": ["10.13.0.1/24", "10.14.0.1/24"]}`,
+		`{"users": [{"email": "u", "pass": "p"}], "address": ["fd13::1/64", "fd14::1/64"]}`,
+		`{"users": [{"email": "u", "pass": "p"}], "address": ["10.13.0.1/24"], "mtu": 1000}`,
+		`{"users": [{"email": "u", "pass": "p"}], "address": ["10.13.0.1/24"], "mtu": 70000}`,
+	} {
+		if _, err := loadJSON(creator)(input); err == nil {
+			t.Errorf("expected an error for %s", input)
+		}
+	}
+}
+
+func TestMasqueInboundConfig(t *testing.T) {
+	build := func(s string) error {
+		c := new(InboundDetourConfig)
+		if err := json.Unmarshal([]byte(s), c); err != nil {
+			return err
+		}
+		_, err := c.Build()
+		return err
+	}
+
+	if err := build(`{
+		"protocol": "masque",
+		"port": 443,
+		"settings": {"users": [{"email": "u@example.com", "pass": "p"}], "address": ["10.13.0.1/24"]},
+		"streamSettings": {"network": "masque", "security": "tls"}
+	}`); err != nil {
+		t.Error(err)
+	}
+	if err := build(`{
+		"protocol": "vless",
+		"port": 443,
+		"settings": {"users": [{"id": "27848739-7e62-4138-9fd3-098a63964b6b"}], "decryption": "none"},
+		"streamSettings": {"network": "masque", "security": "tls"}
+	}`); err == nil {
+		t.Error("expected an error for the masque transport on a vless inbound")
+	}
+}

infra/conf/serial/builder.go

@@ -30,7 +30,7 @@ func MergeConfigFromFiles(files []*core.ConfigSource) (string, error) {
 	if j, ok := creflect.MarshalToJson(c, true); ok {
 		return j, nil
 	}
-	return "", errors.New("marshal to json failed.").AtError()
+	return "", errors.New("marshal to json failed.")
 }
 
 func mergeConfigs(files []*core.ConfigSource) (*conf.Config, error) {

infra/conf/shadowsocks.go

@@ -3,8 +3,6 @@ package conf
 import (
 	"strings"
 
-	"github.com/sagernet/sing-shadowsocks/shadowaead_2022"
-	C "github.com/sagernet/sing/common"
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/protocol"
 	"github.com/xtls/xray-core/common/serial"
@@ -55,7 +53,7 @@ func (v *ShadowsocksServerConfig) Build() (proto.Message, error) {
 		v.Users = v.Clients
 	}
 
-	if C.Contains(shadowaead_2022.List, v.Cipher) {
+	if _, err := shadowsocks_2022.GetCipherMethod(v.Cipher); err == nil {
 		return buildShadowsocks2022(v)
 	}
 
@@ -111,12 +109,14 @@ func (v *ShadowsocksServerConfig) Build() (proto.Message, error) {
 }
 
 func buildShadowsocks2022(v *ShadowsocksServerConfig) (proto.Message, error) {
+	v.Cipher = strings.ToLower(v.Cipher)
 	if len(v.Users) == 0 {
 		config := new(shadowsocks_2022.ServerConfig)
 		config.Method = v.Cipher
 		config.Key = v.Password
 		config.Network = v.NetworkList.Build()
 		config.Email = v.Email
+		config.Level = int32(v.Level)
 		return config, nil
 	}
 
@@ -171,6 +171,7 @@ func buildShadowsocks2022(v *ShadowsocksServerConfig) (proto.Message, error) {
 			Email:   user.Email,
 			Address: user.Address.Build(),
 			Port:    uint32(user.Port),
+			Level:   int32(user.Level),
 		})
 	}
 	return config, nil
@@ -214,63 +215,43 @@ func (v *ShadowsocksClientConfig) Build() (proto.Message, error) {
 		return nil, errors.New(`Shadowsocks settings: "servers" should have one and only one member. Multiple endpoints in "servers" should use multiple Shadowsocks outbounds and routing balancer instead`)
 	}
 
-	if len(v.Servers) == 1 {
-		server := v.Servers[0]
-		if C.Contains(shadowaead_2022.List, server.Cipher) {
-			if server.Address == nil {
-				return nil, errors.New("Shadowsocks server address is not set.")
-			}
-			if server.Port == 0 {
-				return nil, errors.New("Invalid Shadowsocks port.")
-			}
-			if server.Password == "" {
-				return nil, errors.New("Shadowsocks password is not specified.")
-			}
-
-			config := new(shadowsocks_2022.ClientConfig)
-			config.Address = server.Address.Build()
-			config.Port = uint32(server.Port)
-			config.Method = server.Cipher
-			config.Key = server.Password
-			return config, nil
-		}
+	server := v.Servers[0]
+	if server.Address == nil {
+		return nil, errors.New("Shadowsocks server address is not set.")
+	}
+	if server.Port == 0 {
+		return nil, errors.New("Invalid Shadowsocks port.")
+	}
+	if server.Password == "" {
+		return nil, errors.New("Shadowsocks password is not specified.")
 	}
 
+	if _, err := shadowsocks_2022.GetCipherMethod(server.Cipher); err == nil {
+		config := new(shadowsocks_2022.ClientConfig)
+		config.Address = server.Address.Build()
+		config.Port = uint32(server.Port)
+		config.Method = server.Cipher
+		config.Key = server.Password
+		return config, nil
+	}
 	config := new(shadowsocks.ClientConfig)
-	for _, server := range v.Servers {
-		if C.Contains(shadowaead_2022.List, server.Cipher) {
-			return nil, errors.New("Shadowsocks 2022 accept no multi servers")
-		}
-		if server.Address == nil {
-			return nil, errors.New("Shadowsocks server address is not set.")
-		}
-		if server.Port == 0 {
-			return nil, errors.New("Invalid Shadowsocks port.")
-		}
-		if server.Password == "" {
-			return nil, errors.New("Shadowsocks password is not specified.")
-		}
-		account := &shadowsocks.Account{
-			Password: server.Password,
-		}
-		account.CipherType = cipherFromString(server.Cipher)
-		if account.CipherType == shadowsocks.CipherType_UNKNOWN {
-			return nil, errors.New("unknown cipher method: ", server.Cipher)
-		}
-
-		ss := &protocol.ServerEndpoint{
-			Address: server.Address.Build(),
-			Port:    uint32(server.Port),
-			User: &protocol.User{
-				Level:   uint32(server.Level),
-				Email:   server.Email,
-				Account: serial.ToTypedMessage(account),
-			},
-		}
-
-		config.Server = ss
-		break
+	account := &shadowsocks.Account{
+		Password: server.Password,
 	}
+	account.CipherType = cipherFromString(server.Cipher)
+	if account.CipherType == shadowsocks.CipherType_UNKNOWN {
+		return nil, errors.New("unknown cipher method: ", server.Cipher)
+	}
+	ss := &protocol.ServerEndpoint{
+		Address: server.Address.Build(),
+		Port:    uint32(server.Port),
+		User: &protocol.User{
+			Level:   uint32(server.Level),
+			Email:   server.Email,
+			Account: serial.ToTypedMessage(account),
+		},
+	}
+	config.Server = ss
 
 	return config, nil
 }

infra/conf/socks.go

@@ -44,7 +44,6 @@ func (v *SocksServerConfig) Build() (proto.Message, error) {
 	case AuthMethodUserPass:
 		config.AuthType = socks.AuthType_PASSWORD
 	default:
-		// errors.New("unknown socks auth method: ", v.AuthMethod, ". Default to noauth.").AtWarning().WriteToLog()
 		config.AuthType = socks.AuthType_NO_AUTH
 	}
 
@@ -115,7 +114,7 @@ func (v *SocksClientConfig) Build() (proto.Message, error) {
 				user.Email = v.Email
 			} else {
 				if err := json.Unmarshal(rawUser, user); err != nil {
-					return nil, errors.New("failed to parse Socks user").Base(err).AtError()
+					return nil, errors.New("failed to parse Socks user").Base(err)
 				}
 			}
 			account := new(SocksAccount)
@@ -124,7 +123,7 @@ func (v *SocksClientConfig) Build() (proto.Message, error) {
 				account.Password = v.Password
 			} else {
 				if err := json.Unmarshal(rawUser, account); err != nil {
-					return nil, errors.New("failed to parse socks account").Base(err).AtError()
+					return nil, errors.New("failed to parse socks account").Base(err)
 				}
 			}
 			user.Account = serial.ToTypedMessage(account.Build())

infra/conf/transport_finalmask.go

@@ -23,6 +23,7 @@ import (
 	"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"
+	"github.com/xtls/xray-core/transport/internet/finalmask/udphop"
 	"github.com/xtls/xray-core/transport/internet/finalmask/xdns"
 	"github.com/xtls/xray-core/transport/internet/finalmask/xicmp"
 	"github.com/xtls/xray-core/transport/internet/finalmask/xmc"
@@ -83,6 +84,7 @@ var (
 		"xdns":          func() interface{} { return new(Xdns) },
 		"xicmp":         func() interface{} { return new(Xicmp) },
 		"realm":         func() interface{} { return new(Realm) },
+		"udphop":        func() interface{} { return new(UDPHop) },
 	}, "type", "settings")
 )
 
@@ -905,6 +907,59 @@ func (c *Realm) Build() (proto.Message, error) {
 	}, nil
 }
 
+type UDPHop struct {
+	Mode        string     `json:"mode"`
+	Interval    Int32Range `json:"interval"`
+	RemoteIPs   []string   `json:"remoteIPs"`
+	RemotePorts PortList   `json:"remotePorts"`
+}
+
+func (c *UDPHop) Build() (proto.Message, error) {
+	var local, remote, remoteOnce bool
+	for _, mode := range strings.Split(c.Mode, ",") {
+		switch strings.ToLower(mode) {
+		case "intervallocal":
+			local = true
+		case "intervalremote":
+			remote = true
+		case "perconnremote":
+			remoteOnce = true
+		default:
+			return nil, errors.New("invalid mode ", mode)
+		}
+	}
+	var remoteIPs []string
+	for _, ip := range c.RemoteIPs {
+		prefix, err := netip.ParsePrefix(ip)
+		if err == nil {
+			remoteIPs = append(remoteIPs, prefix.String())
+			continue
+		}
+		addr, err := netip.ParseAddr(ip)
+		if err == nil {
+			remoteIPs = append(remoteIPs, netip.PrefixFrom(addr, addr.BitLen()).String())
+			continue
+		}
+		return nil, errors.New("invalid ip ", ip)
+	}
+	interval := c.Interval
+	if interval.From == 0 && interval.To == 0 {
+		interval.From, interval.To = 30, 30
+	}
+	if interval.From < 5 {
+		return nil, errors.New("interval must be at least 5")
+	}
+	return &udphop.Config{
+		Local:       local,
+		Remote:      remote,
+		RemoteOnce:  remoteOnce,
+		IntervalMin: int64(interval.From),
+		IntervalMax: int64(interval.To),
+		RemoteIPs:   remoteIPs,
+		RemotePorts: c.RemotePorts.Build().Ports(),
+	}, nil
+}
+
 type Mask struct {
 	Type     string           `json:"type"`
 	Settings *json.RawMessage `json:"settings"`
@@ -938,7 +993,6 @@ type QuicParamsConfig struct {
 	BrutalUp                      Bandwidth `json:"brutalUp"`
 	BrutalDown                    Bandwidth `json:"brutalDown"`
 	BrutalDisableLossCompensation bool      `json:"brutalDisableLossCompensation"`
-	UdpHop                        UdpHop    `json:"udpHop"`
 	InitStreamReceiveWindow       uint64    `json:"initStreamReceiveWindow"`
 	MaxStreamReceiveWindow        uint64    `json:"maxStreamReceiveWindow"`
 	InitConnectionReceiveWindow   uint64    `json:"initConnectionReceiveWindow"`

infra/conf/transport_internet.go

@@ -36,6 +36,10 @@ func (p TransportProtocol) Build() (string, error) {
 		return "", errors.PrintRemovedFeatureError("QUIC transport (without web service, etc.)", "XHTTP stream-one H3")
 	case "hysteria":
 		return "hysteria", nil
+	case "masque":
+		return "masque", nil
+	case "xdrive":
+		return "xdrive", nil
 	default:
 		return "", errors.New("Config: unknown transport protocol: ", p)
 	}
@@ -59,6 +63,8 @@ type StreamConfig struct {
 	WSSettings          *WebSocketConfig   `json:"wsSettings"`
 	HTTPUPGRADESettings *HttpUpgradeConfig `json:"httpupgradeSettings"`
 	HysteriaSettings    *HysteriaConfig    `json:"hysteriaSettings"`
+	MASQUESettings      *MasqueConfig      `json:"masqueSettings"`
+	XDRIVESettings      *XDriveConfig      `json:"xdriveSettings"`
 	SocketSettings      *SocketConfig      `json:"sockopt"`
 }
 
@@ -192,6 +198,26 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 			Settings:     serial.ToTypedMessage(hs),
 		})
 	}
+	if c.MASQUESettings != nil {
+		ms, err := c.MASQUESettings.Build()
+		if err != nil {
+			return nil, errors.New("Failed to build MASQUE config.").Base(err)
+		}
+		config.TransportSettings = append(config.TransportSettings, &internet.TransportConfig{
+			ProtocolName: "masque",
+			Settings:     serial.ToTypedMessage(ms),
+		})
+	}
+	if c.XDRIVESettings != nil {
+		xs, err := c.XDRIVESettings.Build()
+		if err != nil {
+			return nil, errors.New("Failed to build XDRIVE config.").Base(err)
+		}
+		config.TransportSettings = append(config.TransportSettings, &internet.TransportConfig{
+			ProtocolName: "xdrive",
+			Settings:     serial.ToTypedMessage(xs),
+		})
+	}
 	if c.SocketSettings != nil {
 		ss, err := c.SocketSettings.Build()
 		if err != nil {
@@ -253,10 +279,6 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 				return nil, errors.New("unknown congestion control: ", c.FinalMask.QuicParams.Congestion, ", valid values: reno, bbr, brutal, force-brutal")
 			}
 
-			if (c.FinalMask.QuicParams.UdpHop.Interval.From != 0 && c.FinalMask.QuicParams.UdpHop.Interval.From < 5) || (c.FinalMask.QuicParams.UdpHop.Interval.To != 0 && c.FinalMask.QuicParams.UdpHop.Interval.To < 5) {
-				return nil, errors.New("Interval must be at least 5")
-			}
-
 			if c.FinalMask.QuicParams.InitStreamReceiveWindow > 0 && c.FinalMask.QuicParams.InitStreamReceiveWindow < 16384 {
 				return nil, errors.New("InitStreamReceiveWindow must be at least 16384")
 			}
@@ -290,22 +312,17 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 				BrutalUp:                      up,
 				BrutalDown:                    down,
 				BrutalDisableLossCompensation: c.FinalMask.QuicParams.BrutalDisableLossCompensation,
-				UdpHop: &internet.UdpHop{
-					Ports:       c.FinalMask.QuicParams.UdpHop.PortList.Build().Ports(),
-					IntervalMin: int64(c.FinalMask.QuicParams.UdpHop.Interval.From),
-					IntervalMax: int64(c.FinalMask.QuicParams.UdpHop.Interval.To),
-				},
-				InitStreamReceiveWindow: c.FinalMask.QuicParams.InitStreamReceiveWindow,
-				MaxStreamReceiveWindow:  c.FinalMask.QuicParams.MaxStreamReceiveWindow,
-				InitConnReceiveWindow:   c.FinalMask.QuicParams.InitConnectionReceiveWindow,
-				MaxConnReceiveWindow:    c.FinalMask.QuicParams.MaxConnectionReceiveWindow,
-				MaxIdleTimeout:          c.FinalMask.QuicParams.MaxIdleTimeout,
-				KeepAlivePeriod:         c.FinalMask.QuicParams.KeepAlivePeriod,
-				DisablePathMtuDiscovery: c.FinalMask.QuicParams.DisablePathMTUDiscovery,
-				DisableChromeParrot:     c.FinalMask.QuicParams.DisableChromeParrot,
-				DisableGSO:              c.FinalMask.QuicParams.DisableGSO,
-				MaxIncomingStreams:      c.FinalMask.QuicParams.MaxIncomingStreams,
-				DisableStatelessReset:   c.FinalMask.QuicParams.DisableStatelessReset,
+				InitStreamReceiveWindow:       c.FinalMask.QuicParams.InitStreamReceiveWindow,
+				MaxStreamReceiveWindow:        c.FinalMask.QuicParams.MaxStreamReceiveWindow,
+				InitConnReceiveWindow:         c.FinalMask.QuicParams.InitConnectionReceiveWindow,
+				MaxConnReceiveWindow:          c.FinalMask.QuicParams.MaxConnectionReceiveWindow,
+				MaxIdleTimeout:                c.FinalMask.QuicParams.MaxIdleTimeout,
+				KeepAlivePeriod:               c.FinalMask.QuicParams.KeepAlivePeriod,
+				DisablePathMtuDiscovery:       c.FinalMask.QuicParams.DisablePathMTUDiscovery,
+				DisableChromeParrot:           c.FinalMask.QuicParams.DisableChromeParrot,
+				DisableGSO:                    c.FinalMask.QuicParams.DisableGSO,
+				MaxIncomingStreams:            c.FinalMask.QuicParams.MaxIncomingStreams,
+				DisableStatelessReset:         c.FinalMask.QuicParams.DisableStatelessReset,
 			}
 		}
 	}

infra/conf/transport_method.go

@@ -1,8 +1,9 @@
 package conf
 
 import (
-	"context"
+	"encoding/base64"
 	"encoding/json"
+	"maps"
 	"math/big"
 	"net/url"
 	"sort"
@@ -21,9 +22,12 @@ import (
 	"github.com/xtls/xray-core/transport/internet/httpupgrade"
 	"github.com/xtls/xray-core/transport/internet/hysteria"
 	"github.com/xtls/xray-core/transport/internet/kcp"
+	"github.com/xtls/xray-core/transport/internet/masque"
 	"github.com/xtls/xray-core/transport/internet/splithttp"
 	"github.com/xtls/xray-core/transport/internet/tcp"
 	"github.com/xtls/xray-core/transport/internet/websocket"
+	"github.com/xtls/xray-core/transport/internet/xdrive"
+	"golang.org/x/net/http/httpguts"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -122,7 +126,7 @@ func (v *AuthenticatorRequest) Build() (*http.RequestConfig, error) {
 		for _, key := range headerNames {
 			value := v.Headers[key]
 			if value == nil {
-				return nil, errors.New("empty HTTP header value: " + key).AtError()
+				return nil, errors.New("empty HTTP header value: " + key)
 			}
 			config.Header = append(config.Header, &http.Header{
 				Name:  key,
@@ -190,7 +194,7 @@ func (v *AuthenticatorResponse) Build() (*http.ResponseConfig, error) {
 		for _, key := range headerNames {
 			value := v.Headers[key]
 			if value == nil {
-				return nil, errors.New("empty HTTP header value: " + key).AtError()
+				return nil, errors.New("empty HTTP header value: " + key)
 			}
 			config.Header = append(config.Header, &http.Header{
 				Name:  key,
@@ -240,11 +244,11 @@ func (c *TCPConfig) Build() (proto.Message, error) {
 	if len(c.HeaderConfig) > 0 {
 		headerConfig, _, err := tcpHeaderLoader.Load(c.HeaderConfig)
 		if err != nil {
-			return nil, errors.New("invalid TCP header config").Base(err).AtError()
+			return nil, errors.New("invalid TCP header config").Base(err)
 		}
 		ts, err := headerConfig.(Buildable).Build()
 		if err != nil {
-			return nil, errors.New("invalid TCP header config").Base(err).AtError()
+			return nil, errors.New("invalid TCP header config").Base(err)
 		}
 		config.HeaderSettings = serial.ToTypedMessage(ts)
 	}
@@ -534,10 +538,6 @@ type KCPConfig struct {
 
 // Build implements Buildable.
 func (c *KCPConfig) Build() (proto.Message, error) {
-	if c.HeaderConfig != nil || c.Seed != nil {
-		return nil, errors.PrintRemovedFeatureError("mkcp header & seed", "finalmask/udp header-* & mkcp-original & mkcp-aes128gcm")
-	}
-
 	config := common.Must2(internet.CreateTransportConfig(kcp.ProtocolName)).(*kcp.Config)
 
 	if c.Mtu != nil {
@@ -560,16 +560,16 @@ func (c *KCPConfig) Build() (proto.Message, error) {
 	}
 
 	if config.Mtu < 21 {
-		return nil, errors.New("Mtu must be at least 21").AtError()
+		return nil, errors.New("MTU must be at least 21")
 	}
 	if config.Tti < 10 || config.Tti > 1000 {
-		return nil, errors.New("invalid mKCP TTI: ", c.Tti).AtError()
+		return nil, errors.New("TTI must be between 10 and 1000")
 	}
 	if config.CwndMultiplier < 1 {
-		return nil, errors.New("CwndMultiplier must be at least 1").AtError()
+		return nil, errors.New("CwndMultiplier must be at least 1")
 	}
 	if config.GetSendingBufferSize() == 0 {
-		return nil, errors.New("MaxSendingWindow must be >= Mtu").AtError()
+		return nil, errors.New("MaxSendingWindow must be at least ", config.Mtu)
 	}
 
 	return config, nil
@@ -739,11 +739,6 @@ func (b Bandwidth) Bps() (uint64, error) {
 	return uint64(val*float64(mul)) / 8, nil
 }
 
-type UdpHop struct {
-	PortList PortList   `json:"ports"`
-	Interval Int32Range `json:"interval"`
-}
-
 type Masquerade struct {
 	Type string `json:"type"`
 
@@ -760,14 +755,8 @@ type Masquerade struct {
 }
 
 type HysteriaConfig struct {
-	Version int32  `json:"version"`
-	Auth    string `json:"auth"`
-
-	Congestion *string    `json:"congestion"`
-	Up         *Bandwidth `json:"up"`
-	Down       *Bandwidth `json:"down"`
-	UdpHop     *UdpHop    `json:"udphop"`
-
+	Version        int32      `json:"version"`
+	Auth           string     `json:"auth"`
 	UdpIdleTimeout int64      `json:"udpIdleTimeout"`
 	Masquerade     Masquerade `json:"masquerade"`
 }
@@ -777,10 +766,6 @@ func (c *HysteriaConfig) Build() (proto.Message, error) {
 		return nil, errors.New("version != 2")
 	}
 
-	if c.Congestion != nil || c.Up != nil || c.Down != nil || c.UdpHop != nil {
-		errors.LogWarning(context.Background(), "congestion & up & down & udphop move to finalmask/quicParams")
-	}
-
 	if c.UdpIdleTimeout != 0 && (c.UdpIdleTimeout < 2 || c.UdpIdleTimeout > 600) {
 		return nil, errors.New("UdpIdleTimeout must be between 2 and 600")
 	}
@@ -805,6 +790,63 @@ func (c *HysteriaConfig) Build() (proto.Message, error) {
 	return config, nil
 }
 
+type MasqueConfig struct {
+	Host    string            `json:"host"`
+	Path    string            `json:"path"`
+	User    string            `json:"user"`
+	Pass    string            `json:"pass"`
+	Headers map[string]string `json:"headers"`
+}
+
+func (c *MasqueConfig) Build() (proto.Message, error) {
+	path := c.Path
+	if path == "" {
+		path = masque.DefaultPath
+	}
+	path = strings.NewReplacer(
+		"{target}", "*", "{ipproto}", "*",
+		"{?target,ipproto}", "?target=*&ipproto=*", "{?ipproto,target}", "?ipproto=*&target=*",
+		"{&target,ipproto}", "&target=*&ipproto=*", "{&ipproto,target}", "&ipproto=*&target=*",
+	).Replace(path)
+	if !strings.HasPrefix(path, "/") || strings.ContainsAny(path, "{}") {
+		return nil, errors.New(`invalid "path": `, path, `, only the variables {target} and {ipproto} are supported`)
+	}
+	if c.Host != "" {
+		if u, err := url.Parse("https://" + c.Host); err != nil || u.Host != c.Host {
+			return nil, errors.New(`invalid "host": `, c.Host)
+		}
+	}
+	for k, v := range c.Headers {
+		if !httpguts.ValidHeaderFieldName(k) || !httpguts.ValidHeaderFieldValue(v) {
+			return nil, errors.New(`invalid header in "headers": `, strconv.Quote(k))
+		}
+		switch strings.ToLower(k) {
+		case "host", "capsule-protocol":
+			return nil, errors.New(`"headers" can't contain "`, k, `"`)
+		case "authorization":
+			if c.User != "" || c.Pass != "" {
+				return nil, errors.New(`"headers" can't contain "`, k, `" when "user" or "pass" is set`)
+			}
+		}
+	}
+	headers := c.Headers
+	if c.User != "" || c.Pass != "" {
+		if strings.Contains(c.User, ":") {
+			return nil, errors.New(`invalid "user": `, c.User)
+		}
+		headers = maps.Clone(c.Headers)
+		if headers == nil {
+			headers = make(map[string]string)
+		}
+		headers["Authorization"] = "Basic " + base64.StdEncoding.EncodeToString([]byte(c.User+":"+c.Pass))
+	}
+	return &masque.Config{
+		Host:    c.Host,
+		Path:    path,
+		Headers: headers,
+	}, nil
+}
+
 func readFileOrString(f string, s []string) ([]byte, error) {
 	if len(f) > 0 {
 		return filesystem.ReadCert(f)
@@ -814,3 +856,50 @@ func readFileOrString(f string, s []string) ([]byte, error) {
 	}
 	return nil, errors.New("both file and bytes are empty.")
 }
+
+type XDriveConfig struct {
+	RemoteFolder      string          `json:"remoteFolder"`
+	Service           string          `json:"service"`
+	Secrets           []string        `json:"secrets"`
+	SegmentBytes      uint32          `json:"segmentBytes"`
+	FlushIntervalMs   uint32          `json:"flushIntervalMs"`
+	PollIntervalMs    uint32          `json:"pollIntervalMs"`
+	MaxPollIntervalMs uint32          `json:"maxPollIntervalMs"`
+	SessionTTLSeconds uint32          `json:"sessionTtlSeconds"`
+	Concurrency       uint32          `json:"concurrency"`
+	EagerWindowMs     uint32          `json:"eagerWindowMs"`
+	HoleTimeoutMs     uint32          `json:"holeTimeoutMs"`
+	Template          json.RawMessage `json:"template"`
+}
+
+// Build implements Buildable.
+func (c *XDriveConfig) Build() (proto.Message, error) {
+	switch c.Service {
+	case "local":
+	case "Google Drive":
+		if len(c.Secrets) != 3 {
+			return nil, errors.New("Google Drive needs 3 secrets in order of ClientID, ClientSecret, RefreshToken")
+		}
+	case "template":
+		if len(c.Template) == 0 {
+			return nil, errors.New(`service "template" needs a "template" object`)
+		}
+	default:
+		return nil, errors.New("unsupported service")
+	}
+	config := &xdrive.Config{
+		RemoteFolder:      c.RemoteFolder,
+		Service:           c.Service,
+		Secrets:           c.Secrets,
+		SegmentBytes:      c.SegmentBytes,
+		FlushIntervalMs:   c.FlushIntervalMs,
+		PollIntervalMs:    c.PollIntervalMs,
+		MaxPollIntervalMs: c.MaxPollIntervalMs,
+		SessionTtlSeconds: c.SessionTTLSeconds,
+		Concurrency:       c.Concurrency,
+		EagerWindowMs:     c.EagerWindowMs,
+		HoleTimeoutMs:     c.HoleTimeoutMs,
+		Template:          string(c.Template),
+	}
+	return config, nil
+}

infra/conf/transport_test.go

@@ -291,3 +291,76 @@ func TestHeaderCustomUDPBuildRejectsExprWithoutArgs(t *testing.T) {
 		t.Fatalf("expected transform arg rejection, got %v", err)
 	}
 }
+
+func TestXDriveStreamConfig(t *testing.T) {
+	config := new(StreamConfig)
+	if err := json.Unmarshal([]byte(`{
+		"method": "xdrive",
+		"xdriveSettings": {
+			"remoteFolder": "/tmp/xdrive",
+			"service": "local"
+		}
+	}`), config); err != nil {
+		t.Fatalf("Unmarshal: %v", err)
+	}
+
+	built, err := config.Build()
+	if err != nil {
+		t.Fatalf("Build: %v", err)
+	}
+	if built.ProtocolName != "xdrive" {
+		t.Fatalf("ProtocolName is %q, want %q", built.ProtocolName, "xdrive")
+	}
+	if len(built.TransportSettings) != 1 || built.TransportSettings[0].ProtocolName != "xdrive" {
+		t.Fatalf("TransportSettings is %v, want a single xdrive entry", built.TransportSettings)
+	}
+}
+
+func TestXDriveRejectsUnknownService(t *testing.T) {
+	config := new(XDriveConfig)
+	if err := json.Unmarshal([]byte(`{"remoteFolder": "/tmp/xdrive", "service": "Dropbox"}`), config); err != nil {
+		t.Fatalf("Unmarshal: %v", err)
+	}
+	if _, err := config.Build(); err == nil {
+		t.Fatal("Build accepted an unsupported service")
+	}
+}
+
+func TestXDriveTemplateStreamConfig(t *testing.T) {
+	config := new(StreamConfig)
+	if err := json.Unmarshal([]byte(`{
+		"method": "xdrive",
+		"xdriveSettings": {
+			"remoteFolder": "folder",
+			"service": "template",
+			"secrets": ["user", "pass"],
+			"template": {
+				"flatten": true,
+				"auth": {"type": "basic", "username": "{secret0}", "password": "{secret1}"},
+				"put": {"method": "PUT", "url": "https://dav.example/{folder}/{name}"},
+				"get": {"method": "GET", "url": "https://dav.example/{folder}/{name}"},
+				"delete": {"method": "DELETE", "url": "https://dav.example/{folder}/{name}"},
+				"list": {"method": "PROPFIND", "url": "https://dav.example/{folder}/", "namesRegex": "<d:href>/folder/([^<]+)</d:href>"}
+			}
+		}
+	}`), config); err != nil {
+		t.Fatalf("Unmarshal: %v", err)
+	}
+	built, err := config.Build()
+	if err != nil {
+		t.Fatalf("Build: %v", err)
+	}
+	if built.ProtocolName != "xdrive" {
+		t.Fatalf("ProtocolName is %q, want xdrive", built.ProtocolName)
+	}
+}
+
+func TestXDriveTemplateNeedsTemplate(t *testing.T) {
+	config := new(XDriveConfig)
+	if err := json.Unmarshal([]byte(`{"remoteFolder": "f", "service": "template"}`), config); err != nil {
+		t.Fatalf("Unmarshal: %v", err)
+	}
+	if _, err := config.Build(); err == nil {
+		t.Fatal("Build accepted a template service without a template")
+	}
+}

infra/conf/tun.go

@@ -20,6 +20,7 @@ type TunConfig struct {
 	UserLevel              uint32   `json:"userLevel"`
 	AutoSystemRoutingTable []string `json:"autoSystemRoutingTable"`
 	AutoOutboundsInterface *string  `json:"autoOutboundsInterface"`
+	AutoSystemDNS          bool     `json:"autoSystemDNS"`
 }
 
 func (v *TunConfig) Build() (proto.Message, error) {
@@ -31,6 +32,7 @@ func (v *TunConfig) Build() (proto.Message, error) {
 		DNS:                    v.DNS,
 		UserLevel:              v.UserLevel,
 		AutoSystemRoutingTable: v.AutoSystemRoutingTable,
+		AutoSystemDns:          v.AutoSystemDNS,
 	}
 	if v.AutoOutboundsInterface != nil {
 		config.AutoOutboundsInterface = *v.AutoOutboundsInterface

infra/conf/vless.go

@@ -312,6 +312,9 @@ func (c *VLessOutboundConfig) Build() (proto.Message, error) {
 				if err := json.Unmarshal(rawUser, account); err != nil {
 					return nil, errors.New(`VLESS users: invalid user`).Base(err)
 				}
+				// validateOutboundTransportSecurity needs to see these
+				c.Encryption = account.Encryption
+				c.Address = rec.Address
 				if account.Reverse != nil { // may not be reached: error json unmarshal
 					return nil, errors.New(`VLESS users: please use simplified outbound's config style to use "reverse"`)
 				}

infra/conf/wireguard.go

@@ -59,14 +59,13 @@ func (c *WireGuardPeerConfig) Build() (*wireguard.PeerConfig, error) {
 type WireGuardConfig struct {
 	IsClient bool `json:""`
 
-	NoKernelTun    bool                   `json:"noKernelTun"`
-	SecretKey      string                 `json:"secretKey"`
-	Address        []string               `json:"address"`
-	Peers          []*WireGuardPeerConfig `json:"peers"`
-	MTU            int32                  `json:"mtu"`
-	Reserved       []byte                 `json:"reserved"`
-	DomainStrategy string                 `json:"domainStrategy"`
-	DNS            []string               `json:"remoteDNS"`
+	NoKernelTun bool                   `json:"noKernelTun"`
+	SecretKey   string                 `json:"secretKey"`
+	Address     []string               `json:"address"`
+	Peers       []*WireGuardPeerConfig `json:"peers"`
+	MTU         int32                  `json:"mtu"`
+	Reserved    []byte                 `json:"reserved"`
+	DNS         []string               `json:"remoteDNS"`
 }
 
 func (c *WireGuardConfig) Build() (proto.Message, error) {
@@ -125,21 +124,6 @@ func (c *WireGuardConfig) Build() (proto.Message, error) {
 	}
 	config.Reserved = c.Reserved
 
-	switch strings.ToLower(c.DomainStrategy) {
-	case "forceip", "":
-		config.DomainStrategy = wireguard.DeviceConfig_FORCE_IP
-	case "forceipv4":
-		config.DomainStrategy = wireguard.DeviceConfig_FORCE_IP4
-	case "forceipv6":
-		config.DomainStrategy = wireguard.DeviceConfig_FORCE_IP6
-	case "forceipv4v6":
-		config.DomainStrategy = wireguard.DeviceConfig_FORCE_IP46
-	case "forceipv6v4":
-		config.DomainStrategy = wireguard.DeviceConfig_FORCE_IP64
-	default:
-		return nil, errors.New("unsupported domain strategy: ", c.DomainStrategy)
-	}
-
 	config.IsClient = c.IsClient
 	config.NoKernelTun = c.NoKernelTun
 	config.DNS = c.DNS

infra/conf/xray.go

@@ -16,6 +16,7 @@ import (
 	"github.com/xtls/xray-core/common/serial"
 	core "github.com/xtls/xray-core/core"
 	"github.com/xtls/xray-core/proxy/freedom"
+	"github.com/xtls/xray-core/proxy/masque"
 	"github.com/xtls/xray-core/transport/internet"
 )
 
@@ -32,6 +33,7 @@ var (
 		"trojan":        func() interface{} { return new(TrojanServerConfig) },
 		"wireguard":     func() interface{} { return &WireGuardConfig{IsClient: false} },
 		"hysteria":      func() interface{} { return new(HysteriaServerConfig) },
+		"masque":        func() interface{} { return new(MasqueServerConfig) },
 		"tun":           func() interface{} { return new(TunConfig) },
 	}, "protocol", "settings")
 
@@ -48,6 +50,7 @@ var (
 		"vmess":       func() interface{} { return new(VMessOutboundConfig) },
 		"trojan":      func() interface{} { return new(TrojanClientConfig) },
 		"hysteria":    func() interface{} { return new(HysteriaClientConfig) },
+		"masque":      func() interface{} { return new(MasqueClientConfig) },
 		"dns":         func() interface{} { return new(DNSOutboundConfig) },
 		"wireguard":   func() interface{} { return &WireGuardConfig{IsClient: true} },
 	}, "protocol", "settings")
@@ -203,6 +206,9 @@ func (c *InboundDetourConfig) Build() (*core.InboundHandlerConfig, error) {
 	if err != nil {
 		return nil, errors.New("failed to build inbound handler for protocol ", c.Protocol).Base(err)
 	}
+	if _, ok := ts.(*masque.ServerConfig); !ok && receiverSettings.StreamSettings != nil && receiverSettings.StreamSettings.ProtocolName == "masque" {
+		return nil, errors.New("the masque transport can only be used by the masque inbound")
+	}
 
 	return &core.InboundHandlerConfig{
 		Tag:              c.Tag,
@@ -242,7 +248,7 @@ func validateOutboundTransportSecurity(rawConfig interface{}, senderSettings *pr
 		if vlessCfg.Encryption != "" && vlessCfg.Encryption != "none" {
 			return nil
 		}
-		if requiresTransportSecurity(vlessCfg.Vnext[0].Address) {
+		if requiresTransportSecurity(vlessCfg.Address) {
 			return errors.New("vless without TLS or other encryption is prohibited unless the server address is a private IP or domain")
 		}
 	}
@@ -338,6 +344,14 @@ func (c *OutboundDetourConfig) Build() (*core.OutboundHandlerConfig, error) {
 		return nil, err
 	}
 
+	if _, ok := ts.(*masque.ClientConfig); ok {
+		if ms := senderSettings.MultiplexSettings; ms != nil && ms.Enabled {
+			return nil, errors.New(`masque outbound does not support "mux"`)
+		}
+	} else if senderSettings.StreamSettings != nil && senderSettings.StreamSettings.ProtocolName == "masque" {
+		return nil, errors.New("the masque transport can only be used by the masque outbound")
+	}
+
 	if fc, ok := ts.(*freedom.Config); ok {
 		if senderSettings.StreamSettings != nil &&
 			senderSettings.StreamSettings.SocketSettings != nil &&

infra/vformat/main.go

@@ -1,15 +1,18 @@
 package main
 
 import (
-	"errors"
+	"bytes"
 	"flag"
 	"fmt"
-	"go/build"
 	"os"
-	"os/exec"
 	"path/filepath"
 	"runtime"
+	"sort"
 	"strings"
+	"sync"
+	"sync/atomic"
+
+	"mvdan.cc/gofumpt/format"
 )
 
 var (
@@ -23,101 +26,27 @@ var (
 	isFormat bool
 )
 
-// envFile returns the name of the Go environment configuration file.
-// Copy from https://github.com/golang/go/blob/c4f2a9788a7be04daf931ac54382fbe2cb754938/src/cmd/go/internal/cfg/cfg.go#L150-L166
-func envFile() (string, error) {
-	if file := os.Getenv("GOENV"); file != "" {
-		if file == "off" {
-			return "", errors.New("GOENV=off")
-		}
-		return file, nil
-	}
-	dir, err := os.UserConfigDir()
+func getModuleInfo(pwd string) (modPath, langVersion string, err error) {
+	data, err := os.ReadFile(filepath.Join(pwd, "go.mod"))
 	if err != nil {
-		return "", err
+		return "", "", err
 	}
-	if dir == "" {
-		return "", errors.New("missing user-config dir")
-	}
-	return filepath.Join(dir, "go", "env"), nil
-}
-
-// GetRuntimeEnv returns the value of runtime environment variable,
-// that is set by running following command: `go env -w key=value`.
-func GetRuntimeEnv(key string) (string, error) {
-	file, err := envFile()
-	if err != nil {
-		return "", err
-	}
-	if file == "" {
-		return "", errors.New("missing runtime env file")
-	}
-	var data []byte
-	var runtimeEnv string
-	data, readErr := os.ReadFile(file)
-	if readErr != nil {
-		return "", readErr
-	}
-	envStrings := strings.Split(string(data), "\n")
-	for _, envItem := range envStrings {
-		envItem = strings.TrimSuffix(envItem, "\r")
-		envKeyValue := strings.Split(envItem, "=")
-		if len(envKeyValue) == 2 && strings.TrimSpace(envKeyValue[0]) == key {
-			runtimeEnv = strings.TrimSpace(envKeyValue[1])
-		}
-	}
-	return runtimeEnv, nil
-}
-
-// GetGOBIN returns GOBIN environment variable as a string. It will NOT be empty.
-func GetGOBIN() string {
-	// The one set by user explicitly by `export GOBIN=/path` or `env GOBIN=/path command`
-	GOBIN := os.Getenv("GOBIN")
-	if GOBIN == "" {
-		var err error
-		// The one set by user by running `go env -w GOBIN=/path`
-		GOBIN, err = GetRuntimeEnv("GOBIN")
-		if err != nil {
-			// The default one that Golang uses
-			return filepath.Join(build.Default.GOPATH, "bin")
-		}
-		if GOBIN == "" {
-			return filepath.Join(build.Default.GOPATH, "bin")
-		}
-		return GOBIN
-	}
-	return GOBIN
-}
-
-func Run(binary string, args []string) ([]byte, error) {
-	cmd := exec.Command(binary, args...)
-	cmd.Env = append(cmd.Env, os.Environ()...)
-	output, cmdErr := cmd.CombinedOutput()
-	if cmdErr != nil {
-		return nil, cmdErr
-	}
-	return output, nil
-}
-
-func RunMany(binary string, args, files []string) bool {
-	fmt.Println("Processing with", binary, args, "...")
-
-	formatRequired := false
-	maxTasks := make(chan struct{}, runtime.NumCPU())
-	for _, file := range files {
-		maxTasks <- struct{}{}
-		go func(file string) {
-			output, err := Run(binary, append(args, file))
-			if err != nil {
-				fmt.Println(err)
-			} else if len(output) > 0 {
-				fmt.Println(string(output))
-				formatRequired = true
+	for _, line := range strings.Split(string(data), "\n") {
+		fields := strings.Fields(line)
+		if len(fields) >= 2 {
+			switch fields[0] {
+			case "module":
+				modPath = fields[1]
+			case "go":
+				langVersion = "go" + strings.TrimPrefix(fields[1], "go")
 			}
-			<-maxTasks
-		}(file)
+		}
 	}
-	return formatRequired
+	return modPath, langVersion, nil
+}
+
+func formatGoSource(src []byte, opts format.Options) ([]byte, error) {
+	return format.Source(src, opts)
 }
 
 func main() {
@@ -150,26 +79,76 @@ func main() {
 	}
 
 	pwd := *directory
-	GOBIN := GetGOBIN()
-	binPath := os.Getenv("PATH")
-	pathSlice := []string{pwd, GOBIN, binPath}
-	binPath = strings.Join(pathSlice, string(os.PathListSeparator))
-	os.Setenv("PATH", binPath)
-
-	suffix := ""
-	if runtime.GOOS == "windows" {
-		suffix = ".exe"
-	}
-	gofmt := "gofumpt" + suffix
-
-	if gofmtPath, err := exec.LookPath(gofmt); err != nil {
-		fmt.Println("Can not find", gofmt, "in system path or current working directory.")
+	modPath, langVersion, modErr := getModuleInfo(pwd)
+	if modErr != nil {
+		fmt.Println("Error reading go.mod:", modErr)
 		os.Exit(1)
-	} else {
-		gofmt = gofmtPath
+	}
+	opts := format.Options{
+		LangVersion: langVersion,
+		ModulePath:  modPath,
+	}
+
+	if isFormat {
+		fmt.Println("Formatting Go source files...")
+	} else if isCheck {
+		fmt.Println("Checking files thar are not properly formatted...")
+	}
+
+	jobs := make(chan string, runtime.NumCPU())
+	var wg sync.WaitGroup
+	var formatRequired atomic.Bool
+	var hasErrors atomic.Bool
+
+	for i := 0; i < runtime.NumCPU(); i++ {
+		wg.Go(func() {
+			for path := range jobs {
+				src, err := os.ReadFile(path)
+				if err != nil {
+					fmt.Fprintf(os.Stderr, "Error reading %s: %v\n", path, err)
+					hasErrors.Store(true)
+					continue
+				}
+
+				formatted, err := formatGoSource(src, opts)
+				if err != nil {
+					fmt.Fprintf(os.Stderr, "Error formatting %s: %v\n", path, err)
+					hasErrors.Store(true)
+					continue
+				}
+
+				if !bytes.Equal(src, formatted) {
+					var diffText []byte
+					if isDryrun {
+						newName := filepath.ToSlash(path)
+						oldName := newName + ".orig"
+						diffText = diff(oldName, src, newName, formatted)
+					}
+					if isFormat {
+						info, statErr := os.Stat(path)
+						if statErr != nil {
+							fmt.Fprintf(os.Stderr, "Error stating %s: %v\n", path, statErr)
+							hasErrors.Store(true)
+							continue
+						}
+						if writeErr := os.WriteFile(path, formatted, info.Mode().Perm()); writeErr != nil {
+							fmt.Fprintf(os.Stderr, "Error writing %s: %v\n", path, writeErr)
+							hasErrors.Store(true)
+							continue
+						}
+					}
+
+					formatRequired.Store(true)
+					if isDryrun && len(diffText) > 0 {
+						fmt.Printf("%s\n%s", path, diffText)
+					} else {
+						fmt.Println(path)
+					}
+				}
+			}
+		})
 	}
 
-	rawFilesSlice := make([]string, 0, 1000)
 	walkErr := filepath.Walk(pwd, func(path string, info os.FileInfo, err error) error {
 		if err != nil {
 			fmt.Println(err)
@@ -186,51 +165,206 @@ func main() {
 			!strings.HasSuffix(filename, ".pb.go") &&
 			!strings.Contains(dir, filepath.Join("testing", "mocks")) &&
 			!strings.Contains(path, filepath.Join("main", "distro", "all", "all.go")) {
-			rawFilesSlice = append(rawFilesSlice, path)
+			jobs <- path
 		}
 
 		return nil
 	})
+	close(jobs)
+	wg.Wait()
+
 	if walkErr != nil {
 		fmt.Println(walkErr)
 		os.Exit(1)
 	}
 
-	if isFormat {
-		gofmtArgs := []string{
-			"-l", "-e", "-w",
-		}
+	if hasErrors.Load() {
+		os.Exit(1)
+	}
 
-		fmt.Println("Formatting Go source files...")
-		RunMany(gofmt, gofmtArgs, rawFilesSlice)
-		fmt.Println("Do NOT forget to commit file changes.")
+	if isFormat {
+		if formatRequired.Load() {
+			fmt.Println("Do NOT forget to commit file changes.")
+		}
 	}
 
 	if isCheck {
-		gofmtListArgs := []string{
-			"-l", "-e",
-		}
-
-		fmt.Println("Checking files thar are not properly formatted...")
-		formatRequired := RunMany(gofmt, gofmtListArgs, rawFilesSlice)
-		if formatRequired {
+		if formatRequired.Load() {
 			fmt.Println("Format problem(s) found.")
-		}
-
-		if isDryrun {
-			if formatRequired {
-				gofmtShowArgs := []string{
-					"-d", "-e",
-				}
-				RunMany(gofmt, gofmtShowArgs, rawFilesSlice)
-			}
-		}
-
-		if formatRequired {
-			fmt.Println("Please run 'go install -v mvdan.cc/gofumpt@latest', then run 'go run ./infra/vformat/main.go' to format the Go source files.")
+			fmt.Println("Please run 'go run ./infra/vformat/main.go' to format the Go source files.")
 			os.Exit(1)
 		} else {
 			fmt.Println("All Go source file format check has been passed.")
 		}
 	}
 }
+
+// diff algorithm copied from mvdan.cc/gofumpt/internal/govendor/diff
+type pair struct{ x, y int }
+
+func diff(oldName string, old []byte, newName string, new []byte) []byte {
+	if bytes.Equal(old, new) {
+		return nil
+	}
+	x := diffLines(old)
+	y := diffLines(new)
+
+	var out bytes.Buffer
+	fmt.Fprintf(&out, "diff %s %s\n", oldName, newName)
+	fmt.Fprintf(&out, "--- %s\n", oldName)
+	fmt.Fprintf(&out, "+++ %s\n", newName)
+
+	var (
+		done  pair
+		chunk pair
+		count pair
+		ctext []string
+	)
+	for _, m := range diffTgs(x, y) {
+		if m.x < done.x {
+			continue
+		}
+		start := m
+		for start.x > done.x && start.y > done.y && x[start.x-1] == y[start.y-1] {
+			start.x--
+			start.y--
+		}
+		end := m
+		for end.x < len(x) && end.y < len(y) && x[end.x] == y[end.y] {
+			end.x++
+			end.y++
+		}
+
+		for _, s := range x[done.x:start.x] {
+			ctext = append(ctext, "-"+s)
+			count.x++
+		}
+		for _, s := range y[done.y:start.y] {
+			ctext = append(ctext, "+"+s)
+			count.y++
+		}
+
+		const C = 3
+		if (end.x < len(x) || end.y < len(y)) &&
+			(end.x-start.x < C || (len(ctext) > 0 && end.x-start.x < 2*C)) {
+			for _, s := range x[start.x:end.x] {
+				ctext = append(ctext, " "+s)
+				count.x++
+				count.y++
+			}
+			done = end
+			continue
+		}
+
+		if len(ctext) > 0 {
+			n := end.x - start.x
+			if n > C {
+				n = C
+			}
+			for _, s := range x[start.x : start.x+n] {
+				ctext = append(ctext, " "+s)
+				count.x++
+				count.y++
+			}
+			done = pair{start.x + n, start.y + n}
+
+			if count.x > 0 {
+				chunk.x++
+			}
+			if count.y > 0 {
+				chunk.y++
+			}
+			fmt.Fprintf(&out, "@@ -%d,%d +%d,%d @@\n", chunk.x, count.x, chunk.y, count.y)
+			for _, s := range ctext {
+				out.WriteString(s)
+			}
+			count.x = 0
+			count.y = 0
+			ctext = ctext[:0]
+		}
+
+		if end.x >= len(x) && end.y >= len(y) {
+			break
+		}
+
+		chunk = pair{end.x - C, end.y - C}
+		for _, s := range x[chunk.x:end.x] {
+			ctext = append(ctext, " "+s)
+			count.x++
+			count.y++
+		}
+		done = end
+	}
+
+	return out.Bytes()
+}
+
+func diffLines(x []byte) []string {
+	l := strings.SplitAfter(string(x), "\n")
+	if l[len(l)-1] == "" {
+		l = l[:len(l)-1]
+	} else {
+		l[len(l)-1] += "\n\\ No newline at end of file\n"
+	}
+	return l
+}
+
+func diffTgs(x, y []string) []pair {
+	m := make(map[string]int)
+	for _, s := range x {
+		if c := m[s]; c > -2 {
+			m[s] = c - 1
+		}
+	}
+	for _, s := range y {
+		if c := m[s]; c > -8 {
+			m[s] = c - 4
+		}
+	}
+
+	var xi, yi, inv []int
+	for i, s := range y {
+		if m[s] == -5 {
+			m[s] = len(yi)
+			yi = append(yi, i)
+		}
+	}
+	for i, s := range x {
+		if j, ok := m[s]; ok && j >= 0 {
+			xi = append(xi, i)
+			inv = append(inv, j)
+		}
+	}
+
+	J := inv
+	n := len(xi)
+	T := make([]int, n)
+	L := make([]int, n)
+	for i := range T {
+		T[i] = n + 1
+	}
+	for i := 0; i < n; i++ {
+		k := sort.Search(n, func(k int) bool {
+			return T[k] >= J[i]
+		})
+		T[k] = J[i]
+		L[i] = k + 1
+	}
+	k := 0
+	for _, v := range L {
+		if k < v {
+			k = v
+		}
+	}
+	seq := make([]pair, 2+k)
+	seq[1+k] = pair{len(x), len(y)}
+	lastj := n
+	for i := n - 1; i >= 0; i-- {
+		if L[i] == k && J[i] < lastj {
+			seq[k] = pair{xi[i], yi[J[i]]}
+			k--
+		}
+	}
+	seq[0] = pair{0, 0}
+	return seq
+}

main/commands/all/api/inbound_user_add.go

@@ -12,6 +12,7 @@ import (
 	"github.com/xtls/xray-core/core"
 	"github.com/xtls/xray-core/infra/conf"
 	"github.com/xtls/xray-core/infra/conf/serial"
+	"github.com/xtls/xray-core/proxy/masque"
 	"github.com/xtls/xray-core/proxy/shadowsocks"
 	"github.com/xtls/xray-core/proxy/shadowsocks_2022"
 	"github.com/xtls/xray-core/proxy/trojan"
@@ -88,6 +89,8 @@ func extractInboundUsers(inb *core.InboundHandlerConfig) []*protocol.User {
 		return ty.Users
 	case *shadowsocks_2022.MultiUserServerConfig:
 		return ty.Users
+	case *masque.ServerConfig:
+		return ty.Users
 	default:
 		fmt.Println("unsupported inbound type")
 	}

main/distro/all/all.go

@@ -41,6 +41,7 @@ import (
 	_ "github.com/xtls/xray-core/proxy/freedom"
 	_ "github.com/xtls/xray-core/proxy/http"
 	_ "github.com/xtls/xray-core/proxy/loopback"
+	_ "github.com/xtls/xray-core/proxy/masque"
 	_ "github.com/xtls/xray-core/proxy/shadowsocks"
 	_ "github.com/xtls/xray-core/proxy/socks"
 	_ "github.com/xtls/xray-core/proxy/trojan"
@@ -54,12 +55,14 @@ import (
 	_ "github.com/xtls/xray-core/transport/internet/grpc"
 	_ "github.com/xtls/xray-core/transport/internet/httpupgrade"
 	_ "github.com/xtls/xray-core/transport/internet/kcp"
+	_ "github.com/xtls/xray-core/transport/internet/masque"
 	_ "github.com/xtls/xray-core/transport/internet/reality"
 	_ "github.com/xtls/xray-core/transport/internet/splithttp"
 	_ "github.com/xtls/xray-core/transport/internet/tcp"
 	_ "github.com/xtls/xray-core/transport/internet/tls"
 	_ "github.com/xtls/xray-core/transport/internet/udp"
 	_ "github.com/xtls/xray-core/transport/internet/websocket"
+	_ "github.com/xtls/xray-core/transport/internet/xdrive"
 
 	// Transport headers
 	_ "github.com/xtls/xray-core/transport/internet/headers/http"

proxy/freedom/freedom.go

@@ -190,6 +190,12 @@ func (h *Handler) matchFinalRule(network net.Network, address net.Address, port
 func (h *Handler) Init(config *Config, pm policy.Manager) error {
 	h.config = config
 	h.policyManager = pm
+	if h.usesDialerProxy { // freedom is not the final outbound, final rules do not apply
+		if len(config.FinalRules) > 0 {
+			errors.LogWarning(context.Background(), `The "finalRules" setting is ignored when "sockopt.dialerProxy" is set, since freedom is not the final outbound.`)
+		}
+		return nil
+	}
 	h.finalRules = make([]*FinalRule, 0, len(config.FinalRules))
 	for _, rc := range config.FinalRules {
 		rule, err := buildFinalRule(rc)
@@ -253,7 +259,10 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 	ob.Name = "freedom"
 	ob.CanSpliceCopy = 1
 	inbound := session.InboundFromContext(ctx)
-	defaultRule := getDefaultFinalRule(inbound)
+	var defaultRule *FinalRule
+	if !h.usesDialerProxy { // freedom is not the final outbound, final rules do not apply (and the domain is not resolved)
+		defaultRule = getDefaultFinalRule(inbound)
+	}
 
 	destination := ob.Target
 	origTargetAddr := ob.OriginalTarget.Address
@@ -342,15 +351,11 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 		return h.blackhole(ctx, input, output, blockedRule, blockedDest)
 	}
 	if destination.Address.Family().IsDomain() && (defaultRule != nil || len(h.finalRules) > 0) {
-		if h.usesDialerProxy {
-			errors.LogInfo(ctx, "skipping final rule check for proxied remote endpoint, original target: ", destination)
-		} else {
-			// pre-check may fail or dialer may select another IP
-			remoteDest := net.DestinationFromAddr(conn.RemoteAddr())
-			if rule := h.matchFinalRule(remoteDest.Network, remoteDest.Address, remoteDest.Port, defaultRule); rule != nil && rule.action == RuleAction_Block {
-				conn.Close()
-				return h.blackhole(ctx, input, output, rule, &remoteDest)
-			}
+		// pre-check may fail or dialer may select another IP
+		remoteDest := net.DestinationFromAddr(conn.RemoteAddr())
+		if rule := h.matchFinalRule(remoteDest.Network, remoteDest.Address, remoteDest.Port, defaultRule); rule != nil && rule.action == RuleAction_Block {
+			conn.Close()
+			return h.blackhole(ctx, input, output, rule, &remoteDest)
 		}
 	}
 
@@ -462,7 +467,7 @@ func NewPacketReader(conn net.Conn, h *Handler, defaultRule *FinalRule, UDPOverr
 	if statConn != nil {
 		counter = statConn.ReadCounter
 	}
-	if c, ok := iConn.(*internet.PacketConnWrapper); ok {
+	if c, ok := iConn.(*net.PacketConnWrapper); ok {
 		isOverridden := false
 		if UDPOverride.Address != nil || UDPOverride.Port != 0 {
 			isOverridden = true
@@ -482,7 +487,7 @@ func NewPacketReader(conn net.Conn, h *Handler, defaultRule *FinalRule, UDPOverr
 }
 
 type PacketReader struct {
-	*internet.PacketConnWrapper
+	*net.PacketConnWrapper
 	stats.Counter
 	Handler           *Handler
 	DefaultRule       *FinalRule
@@ -537,7 +542,7 @@ func NewPacketWriter(conn net.Conn, h *Handler, defaultRule *FinalRule, UDPOverr
 	if statConn != nil {
 		counter = statConn.WriteCounter
 	}
-	if c, ok := iConn.(*internet.PacketConnWrapper); ok {
+	if c, ok := iConn.(*net.PacketConnWrapper); ok {
 		// If DialDest is a domain, it will be resolved in dialer
 		// check this behavior and add it to map
 		resolvedUDPAddr := utils.NewTypedSyncMap[string, net.Address]()
@@ -558,7 +563,7 @@ func NewPacketWriter(conn net.Conn, h *Handler, defaultRule *FinalRule, UDPOverr
 }
 
 type PacketWriter struct {
-	*internet.PacketConnWrapper
+	*net.PacketConnWrapper
 	stats.Counter
 	*Handler
 	DefaultRule *FinalRule

proxy/http/server.go

@@ -115,11 +115,7 @@ Start:
 
 	request, err := http.ReadRequest(reader)
 	if err != nil {
-		trace := errors.New("failed to read http request").Base(err)
-		if errors.Cause(err) != io.EOF && !isTimeout(errors.Cause(err)) {
-			trace.AtWarning()
-		}
-		return trace
+		return errors.New("failed to read http request").Base(err)
 	}
 
 	if len(s.config.Accounts) > 0 {
@@ -147,7 +143,7 @@ Start:
 	}
 	dest, err := http_proto.ParseHost(host, defaultPort)
 	if err != nil {
-		return errors.New("malformed proxy host: ", host).AtWarning().Base(err)
+		return errors.New("malformed proxy host: ", host).Base(err)
 	}
 	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
 		From:   conn.RemoteAddr(),
@@ -262,7 +258,7 @@ func (s *Server) handlePlainHTTP(ctx context.Context, request *http.Request, wri
 		requestWriter := buf.NewBufferedWriter(link.Writer)
 		common.Must(requestWriter.SetBuffered(false))
 		if err := request.Write(requestWriter); err != nil {
-			return errors.New("failed to write whole request").Base(err).AtWarning()
+			return errors.New("failed to write whole request").Base(err)
 		}
 		return nil
 	}
@@ -299,7 +295,7 @@ func (s *Server) handlePlainHTTP(ctx context.Context, request *http.Request, wri
 			response.Header.Set("Proxy-Connection", "close")
 		}
 		if err := response.Write(writer); err != nil {
-			return errors.New("failed to write response").Base(err).AtWarning()
+			return errors.New("failed to write response").Base(err)
 		}
 		return nil
 	}

proxy/hysteria/client.go

@@ -62,7 +62,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 
 	conn, err := dialer.Dial(hysteria.ContextWithDatagram(ctx, target.Network == net.Network_UDP), c.server.Destination)
 	if err != nil {
-		return errors.New("failed to find an available destination").AtWarning().Base(err)
+		return errors.New("failed to find an available destination").Base(err)
 	}
 	defer conn.Close()
 	errors.LogInfo(ctx, "tunneling request to ", target, " via ", target.Network, ":", c.server.Destination.NetAddr())
@@ -236,14 +236,14 @@ type UDPReader struct {
 
 func (r *UDPReader) ReadFrom(p []byte) (n int, addr *net.Destination, err error) {
 	for {
-		var buf [hysteria.MaxDatagramFrameSize]byte
+		var packet [1500]byte
 
-		n, err := r.reader.Read(buf[:])
+		n, err := r.reader.Read(packet[:])
 		if err != nil {
 			return 0, nil, err
 		}
 
-		msg, err := ParseUDPMessage(buf[:n])
+		msg, err := ParseUDPMessage(packet[:n])
 		if err != nil {
 			continue
 		}

proxy/hysteria/server.go

@@ -40,11 +40,11 @@ func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) {
 	for _, user := range config.Users {
 		u, err := user.ToMemoryUser()
 		if err != nil {
-			return nil, errors.New("failed to get hysteria user").Base(err).AtError()
+			return nil, errors.New("failed to get hysteria user").Base(err)
 		}
 
 		if err := validator.Add(u); err != nil {
-			return nil, errors.New("failed to add user").Base(err).AtError()
+			return nil, errors.New("failed to add user").Base(err)
 		}
 	}
 

proxy/loopback/loopback.go

@@ -56,7 +56,7 @@ func (l *Loopback) init(config *Config, dispatcherInstance routing.Dispatcher) e
 	if config.Sniffing.GetEnabled() {
 		request, err := proxyman.BuildSniffingRequest(config.Sniffing)
 		if err != nil {
-			return errors.New("failed to build loopback sniffing request").Base(err).AtError()
+			return errors.New("failed to build loopback sniffing request").Base(err)
 		}
 		l.sniffingRequest = request
 	}

proxy/masque/account.go

@@ -0,0 +1,108 @@
+package masque
+
+import (
+	"crypto/subtle"
+	"strings"
+	"sync"
+
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/protocol"
+	"google.golang.org/protobuf/proto"
+)
+
+func (a *Account) AsAccount() (protocol.Account, error) {
+	return &MemoryAccount{Password: a.Password}, nil
+}
+
+type MemoryAccount struct {
+	Password string
+}
+
+func (a *MemoryAccount) Equals(other protocol.Account) bool {
+	b, ok := other.(*MemoryAccount)
+	return ok && a.Password == b.Password
+}
+
+func (a *MemoryAccount) ToProto() proto.Message {
+	return &Account{Password: a.Password}
+}
+
+type validator struct {
+	mu    sync.RWMutex
+	users map[string]*protocol.MemoryUser
+}
+
+func newValidator() *validator {
+	return &validator{users: make(map[string]*protocol.MemoryUser)}
+}
+
+func (v *validator) add(user *protocol.MemoryUser) error {
+	account, ok := user.Account.(*MemoryAccount)
+	if !ok {
+		return errors.New("not a MASQUE account")
+	}
+	if user.Email == "" || strings.Contains(user.Email, ":") {
+		return errors.New("invalid email ", user.Email)
+	}
+	if account.Password == "" {
+		return errors.New("empty password for ", user.Email)
+	}
+	email := strings.ToLower(user.Email)
+	v.mu.Lock()
+	defer v.mu.Unlock()
+	if _, found := v.users[email]; found {
+		return errors.New("user ", user.Email, " already exists")
+	}
+	v.users[email] = user
+	return nil
+}
+
+func (v *validator) delByEmail(email string) (*protocol.MemoryUser, error) {
+	key := strings.ToLower(email)
+	v.mu.Lock()
+	defer v.mu.Unlock()
+	user, found := v.users[key]
+	if !found {
+		return nil, errors.New("user ", email, " not found")
+	}
+	delete(v.users, key)
+	return user, nil
+}
+
+func (v *validator) contains(user *protocol.MemoryUser) bool {
+	v.mu.RLock()
+	defer v.mu.RUnlock()
+	return v.users[strings.ToLower(user.Email)] == user
+}
+
+func (v *validator) get(email, password string) *protocol.MemoryUser {
+	v.mu.RLock()
+	user := v.users[strings.ToLower(email)]
+	v.mu.RUnlock()
+	if user == nil || subtle.ConstantTimeCompare([]byte(user.Account.(*MemoryAccount).Password), []byte(password)) != 1 {
+		return nil
+	}
+	return user
+}
+
+func (v *validator) getByEmail(email string) *protocol.MemoryUser {
+	v.mu.RLock()
+	defer v.mu.RUnlock()
+	return v.users[strings.ToLower(email)]
+}
+
+func (v *validator) getAll() []*protocol.MemoryUser {
+	v.mu.RLock()
+	defer v.mu.RUnlock()
+	users := make([]*protocol.MemoryUser, 0, len(v.users))
+	for _, user := range v.users {
+		users = append(users, user)
+	}
+	return users
+}
+
+func (v *validator) count() int64 {
+	v.mu.RLock()
+	defer v.mu.RUnlock()
+	return int64(len(v.users))
+}

proxy/masque/account_test.go

@@ -0,0 +1,49 @@
+package masque
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"github.com/xtls/xray-core/common/protocol"
+)
+
+func TestValidator(t *testing.T) {
+	v := newValidator()
+	user := &protocol.MemoryUser{Email: "U@example.com", Account: &MemoryAccount{Password: "p"}}
+	require.NoError(t, v.add(user))
+	for _, u := range []*protocol.MemoryUser{
+		{Email: "u@example.com", Account: &MemoryAccount{Password: "other"}},
+		{Account: &MemoryAccount{Password: "p"}},
+		{Email: "a:b", Account: &MemoryAccount{Password: "p"}},
+		{Email: "b@example.com", Account: &MemoryAccount{}},
+	} {
+		require.Error(t, v.add(u), u.Email)
+	}
+
+	require.Equal(t, user, v.get("u@example.com", "p"))
+	require.Equal(t, user, v.get("U@EXAMPLE.COM", "p"))
+	require.Nil(t, v.get("u@example.com", "x"))
+	require.Nil(t, v.get("x@example.com", "p"))
+	require.Nil(t, v.get("", ""))
+	require.Equal(t, user, v.getByEmail("u@example.com"))
+	require.Equal(t, []*protocol.MemoryUser{user}, v.getAll())
+	require.Equal(t, int64(1), v.count())
+
+	require.True(t, v.contains(user))
+	removed, err := v.delByEmail("u@EXAMPLE.com")
+	require.NoError(t, err)
+	require.Equal(t, user, removed)
+	_, err = v.delByEmail("u@example.com")
+	require.Error(t, err)
+	require.False(t, v.contains(user))
+	require.Nil(t, v.get("u@example.com", "p"))
+	require.Zero(t, v.count())
+}
+
+func TestAccount(t *testing.T) {
+	account, err := (&Account{Password: "p"}).AsAccount()
+	require.NoError(t, err)
+	require.True(t, account.Equals(&MemoryAccount{Password: "p"}))
+	require.False(t, account.Equals(&MemoryAccount{Password: "x"}))
+	require.Equal(t, &Account{Password: "p"}, account.ToProto())
+}

proxy/masque/client.go

@@ -0,0 +1,328 @@
+package masque
+
+import (
+	"context"
+	go_errors "errors"
+	"io"
+	"net/netip"
+	"slices"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"golang.zx2c4.com/wireguard/tun"
+
+	"github.com/xtls/xray-core/common"
+	"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/protocol"
+	"github.com/xtls/xray-core/common/session"
+	"github.com/xtls/xray-core/common/signal"
+	"github.com/xtls/xray-core/common/task"
+	"github.com/xtls/xray-core/core"
+	"github.com/xtls/xray-core/features/policy"
+	"github.com/xtls/xray-core/proxy/wireguard"
+	"github.com/xtls/xray-core/transport"
+	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/masque"
+	"github.com/xtls/xray-core/transport/internet/stat"
+	"github.com/xtls/xray-core/transport/internet/tls"
+)
+
+const (
+	establishTimeout = 10 * time.Second
+	retryInterval    = time.Second
+)
+
+type Client struct {
+	server        *protocol.ServerSpec
+	policyManager policy.Manager
+	remoteDNS     []netip.Addr
+
+	ctx    context.Context
+	cancel context.CancelFunc
+
+	tunnel atomic.Pointer[tunnel]
+
+	mu        sync.Mutex
+	lastErr   error
+	lastErrAt time.Time
+}
+
+func NewClient(ctx context.Context, config *ClientConfig) (*Client, error) {
+	v := core.MustFromContext(ctx)
+	p := v.GetFeature(policy.ManagerType()).(policy.Manager)
+
+	streamSettings := session.StreamSettingsFromContext(ctx).(*internet.MemoryStreamConfig)
+	if _, ok := streamSettings.ProtocolSettings.(*masque.Config); !ok {
+		return nil, errors.New("not masque transport")
+	}
+	if tls.ConfigFromStreamSettings(streamSettings) == nil {
+		return nil, errors.New(`MASQUE requires "security": "tls"`)
+	}
+	if config.Server == nil {
+		return nil, errors.New(`no target server found`)
+	}
+	server, err := protocol.NewServerSpecFromPB(config.Server)
+	if err != nil {
+		return nil, errors.New("failed to get server spec").Base(err)
+	}
+
+	dns := config.RemoteDns
+	if len(dns) == 0 {
+		dns = []string{"1.1.1.1", "1.0.0.1", "2606:4700:4700::1111", "2606:4700:4700::1001"}
+	}
+	remoteDNS := make([]netip.Addr, 0, len(dns))
+	for _, s := range dns {
+		addr, err := netip.ParseAddr(s)
+		if err != nil {
+			return nil, errors.New("invalid remote DNS server ", s).Base(err)
+		}
+		remoteDNS = append(remoteDNS, addr)
+	}
+
+	c := &Client{
+		server:        server,
+		policyManager: p,
+		remoteDNS:     remoteDNS,
+	}
+	c.ctx, c.cancel = context.WithCancel(context.Background())
+	return c, nil
+}
+
+func (c *Client) Process(ctx context.Context, link *transport.Link, dialer internet.Dialer) error {
+	outbounds := session.OutboundsFromContext(ctx)
+	ob := outbounds[len(outbounds)-1]
+	if !ob.Target.IsValid() {
+		return errors.New("target not specified")
+	}
+	ob.Name = "masque"
+	ob.CanSpliceCopy = 3
+
+	t, err := c.getTunnel(ctx, dialer)
+	if err != nil {
+		return errors.New("failed to establish CONNECT-IP tunnel").Base(err)
+	}
+
+	var newCtx context.Context
+	var newCancel context.CancelFunc
+	if session.TimeoutOnlyFromContext(ctx) {
+		newCtx, newCancel = context.WithCancel(context.Background())
+	}
+
+	sessionPolicy := c.policyManager.ForLevel(0)
+	ctx, cancel := context.WithCancel(ctx)
+	timer := signal.CancelAfterInactivity(ctx, func() {
+		cancel()
+		if newCancel != nil {
+			newCancel()
+		}
+	}, sessionPolicy.Timeouts.ConnectionIdle)
+
+	if newCtx != nil {
+		ctx = newCtx
+	}
+
+	var reader buf.Reader
+	var writer buf.Writer
+
+	switch ob.Target.Network {
+	case net.Network_TCP:
+		var conn net.Conn
+		var err error
+		if sessionPolicy.Timeouts.Handshake != 0 {
+			timeoutCtx, timeoutCancel := context.WithTimeout(ctx, sessionPolicy.Timeouts.Handshake)
+			conn, err = t.tnet.DialContext(timeoutCtx, "tcp", ob.Target.NetAddr())
+			timeoutCancel()
+		} else {
+			conn, err = t.tnet.Dial("tcp", ob.Target.NetAddr())
+		}
+		if err != nil {
+			return errors.New("failed to create TCP connection").Base(err)
+		}
+		defer conn.Close()
+		reader = buf.NewReader(conn)
+		writer = buf.NewWriter(conn)
+	case net.Network_UDP:
+		conn, err := t.tnet.Dial("udp", ob.Target.NetAddr())
+		if err != nil {
+			return errors.New("failed to create UDP connection").Base(err)
+		}
+		defer conn.Close()
+		uc := &wireguard.UDPConnClient{
+			PacketConn: conn.(*net.PacketConnWrapper).PacketConn,
+			Dest:       conn.RemoteAddr().(*net.UDPAddr),
+		}
+		reader = uc
+		writer = uc
+	default:
+		panic(ob.Target.Network)
+	}
+
+	requestFunc := func() error {
+		defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
+		return buf.Copy(link.Reader, writer, buf.UpdateActivity(timer))
+	}
+
+	responseFunc := func() error {
+		defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
+		return buf.Copy(reader, link.Writer, buf.UpdateActivity(timer))
+	}
+
+	responseDonePost := task.OnSuccess(responseFunc, task.Close(link.Writer))
+	if err := task.Run(ctx, requestFunc, responseDonePost); err != nil {
+		common.Interrupt(link.Reader)
+		common.Interrupt(link.Writer)
+		return errors.New("connection ends").Base(err)
+	}
+
+	return nil
+}
+
+func (c *Client) getTunnel(ctx context.Context, dialer internet.Dialer) (*tunnel, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.ctx.Err() != nil {
+		return nil, errors.New("closed")
+	}
+	if t := c.tunnel.Load(); t != nil {
+		select {
+		case <-t.done:
+		default:
+			return t, nil
+		}
+	}
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
+	if c.lastErr != nil && time.Since(c.lastErrAt) < retryInterval {
+		return nil, c.lastErr
+	}
+
+	t, err := c.establish(ctx, dialer)
+	if err != nil {
+		c.lastErr, c.lastErrAt = err, time.Now()
+		return nil, err
+	}
+	c.lastErr = nil
+	c.tunnel.Store(t)
+	if c.ctx.Err() != nil {
+		if c.tunnel.CompareAndSwap(t, nil) {
+			t.close()
+		}
+		return nil, errors.New("closed")
+	}
+	return t, nil
+}
+
+func (c *Client) establish(ctx context.Context, dialer internet.Dialer) (*tunnel, error) {
+	ctx, cancel := context.WithTimeout(context.WithoutCancel(ctx), establishTimeout)
+	defer cancel()
+	defer context.AfterFunc(c.ctx, cancel)()
+	conn, err := dialer.Dial(ctx, c.server.Destination)
+	if err != nil {
+		return nil, err
+	}
+	mconn, ok := stat.TryUnwrapStatsConn(conn).(*masque.Conn)
+	if !ok {
+		conn.Close()
+		return nil, errors.New("not a CONNECT-IP connection")
+	}
+	t, err := newTunnel(conn, mconn.LocalAddrs(), c.remoteDNS)
+	if err != nil {
+		conn.Close()
+		return nil, err
+	}
+	errors.LogInfo(ctx, "MASQUE: tunnel established from ", mconn.LocalAddrs())
+	return t, nil
+}
+
+func (c *Client) Close() error {
+	c.cancel()
+	if t := c.tunnel.Swap(nil); t != nil {
+		t.close()
+	}
+	return nil
+}
+
+type tunnel struct {
+	conn      stat.Connection
+	dev       tun.Device
+	tnet      *wireguard.Net
+	done      chan struct{}
+	closeOnce sync.Once
+}
+
+func newTunnel(conn stat.Connection, local []netip.Addr, remoteDNS []netip.Addr) (*tunnel, error) {
+	var dns []netip.Addr
+	for _, addr := range remoteDNS {
+		if slices.ContainsFunc(local, func(l netip.Addr) bool { return l.Is4() == addr.Is4() }) {
+			dns = append(dns, addr)
+		}
+	}
+	if len(dns) == 0 {
+		errors.LogWarning(context.Background(), "MASQUE: no remote DNS server is reachable from the assigned addresses ", local, ", domain names will fail to resolve")
+		dns = remoteDNS
+	}
+
+	dev, tnet, _, err := wireguard.CreateNetTUN(local, dns, masque.MinPacketSize, true)
+	if err != nil {
+		return nil, err
+	}
+	t := &tunnel{
+		conn: conn,
+		dev:  dev,
+		tnet: tnet,
+		done: make(chan struct{}),
+	}
+	go t.readFromTunnel()
+	go t.writeToTunnel()
+	return t, nil
+}
+
+func (t *tunnel) readFromTunnel() {
+	defer t.close()
+	b := make([]byte, buf.Size)
+	for {
+		n, err := t.conn.Read(b)
+		if err != nil {
+			if go_errors.Is(err, io.ErrShortBuffer) {
+				continue
+			}
+			errors.LogInfoInner(context.Background(), err, "MASQUE: tunnel closed")
+			return
+		}
+		t.dev.Write([][]byte{b[:n]}, 0)
+	}
+}
+
+func (t *tunnel) writeToTunnel() {
+	bufs := [][]byte{make([]byte, masque.MinPacketSize)}
+	sizes := []int{0}
+	for {
+		if _, err := t.dev.Read(bufs, sizes, 0); err != nil {
+			return
+		}
+		if _, err := t.conn.Write(bufs[0][:sizes[0]]); err != nil {
+			var ptb *masque.PacketTooBigError
+			if go_errors.As(err, &ptb) {
+				go t.dev.Write([][]byte{ptb.ICMP}, 0)
+			}
+		}
+	}
+}
+
+func (t *tunnel) close() {
+	t.closeOnce.Do(func() {
+		close(t.done)
+		t.conn.Close()
+		t.dev.Close()
+	})
+}
+
+func init() {
+	common.Must(common.RegisterConfig((*ClientConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
+		return NewClient(ctx, config.(*ClientConfig))
+	}))
+}

proxy/masque/config.pb.go

@@ -0,0 +1,250 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.36.11
+// 	protoc        v6.33.5
+// source: proxy/masque/config.proto
+
+package masque
+
+import (
+	protocol "github.com/xtls/xray-core/common/protocol"
+	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 ClientConfig struct {
+	state         protoimpl.MessageState   `protogen:"open.v1"`
+	Server        *protocol.ServerEndpoint `protobuf:"bytes,1,opt,name=server,proto3" json:"server,omitempty"`
+	RemoteDns     []string                 `protobuf:"bytes,2,rep,name=remote_dns,json=remoteDns,proto3" json:"remote_dns,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *ClientConfig) Reset() {
+	*x = ClientConfig{}
+	mi := &file_proxy_masque_config_proto_msgTypes[0]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *ClientConfig) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ClientConfig) ProtoMessage() {}
+
+func (x *ClientConfig) ProtoReflect() protoreflect.Message {
+	mi := &file_proxy_masque_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 ClientConfig.ProtoReflect.Descriptor instead.
+func (*ClientConfig) Descriptor() ([]byte, []int) {
+	return file_proxy_masque_config_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *ClientConfig) GetServer() *protocol.ServerEndpoint {
+	if x != nil {
+		return x.Server
+	}
+	return nil
+}
+
+func (x *ClientConfig) GetRemoteDns() []string {
+	if x != nil {
+		return x.RemoteDns
+	}
+	return nil
+}
+
+type Account struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	Password      string                 `protobuf:"bytes,1,opt,name=password,proto3" json:"password,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *Account) Reset() {
+	*x = Account{}
+	mi := &file_proxy_masque_config_proto_msgTypes[1]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *Account) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Account) ProtoMessage() {}
+
+func (x *Account) ProtoReflect() protoreflect.Message {
+	mi := &file_proxy_masque_config_proto_msgTypes[1]
+	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 Account.ProtoReflect.Descriptor instead.
+func (*Account) Descriptor() ([]byte, []int) {
+	return file_proxy_masque_config_proto_rawDescGZIP(), []int{1}
+}
+
+func (x *Account) GetPassword() string {
+	if x != nil {
+		return x.Password
+	}
+	return ""
+}
+
+type ServerConfig struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	Users         []*protocol.User       `protobuf:"bytes,1,rep,name=users,proto3" json:"users,omitempty"`
+	Address       []string               `protobuf:"bytes,2,rep,name=address,proto3" json:"address,omitempty"`
+	Mtu           uint32                 `protobuf:"varint,3,opt,name=mtu,proto3" json:"mtu,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *ServerConfig) Reset() {
+	*x = ServerConfig{}
+	mi := &file_proxy_masque_config_proto_msgTypes[2]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *ServerConfig) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ServerConfig) ProtoMessage() {}
+
+func (x *ServerConfig) ProtoReflect() protoreflect.Message {
+	mi := &file_proxy_masque_config_proto_msgTypes[2]
+	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 ServerConfig.ProtoReflect.Descriptor instead.
+func (*ServerConfig) Descriptor() ([]byte, []int) {
+	return file_proxy_masque_config_proto_rawDescGZIP(), []int{2}
+}
+
+func (x *ServerConfig) GetUsers() []*protocol.User {
+	if x != nil {
+		return x.Users
+	}
+	return nil
+}
+
+func (x *ServerConfig) GetAddress() []string {
+	if x != nil {
+		return x.Address
+	}
+	return nil
+}
+
+func (x *ServerConfig) GetMtu() uint32 {
+	if x != nil {
+		return x.Mtu
+	}
+	return 0
+}
+
+var File_proxy_masque_config_proto protoreflect.FileDescriptor
+
+const file_proxy_masque_config_proto_rawDesc = "" +
+	"\n" +
+	"\x19proxy/masque/config.proto\x12\x11xray.proxy.masque\x1a!common/protocol/server_spec.proto\x1a\x1acommon/protocol/user.proto\"k\n" +
+	"\fClientConfig\x12<\n" +
+	"\x06server\x18\x01 \x01(\v2$.xray.common.protocol.ServerEndpointR\x06server\x12\x1d\n" +
+	"\n" +
+	"remote_dns\x18\x02 \x03(\tR\tremoteDns\"%\n" +
+	"\aAccount\x12\x1a\n" +
+	"\bpassword\x18\x01 \x01(\tR\bpassword\"l\n" +
+	"\fServerConfig\x120\n" +
+	"\x05users\x18\x01 \x03(\v2\x1a.xray.common.protocol.UserR\x05users\x12\x18\n" +
+	"\aaddress\x18\x02 \x03(\tR\aaddress\x12\x10\n" +
+	"\x03mtu\x18\x03 \x01(\rR\x03mtuBU\n" +
+	"\x15com.xray.proxy.masqueP\x01Z&github.com/xtls/xray-core/proxy/masque\xaa\x02\x11Xray.Proxy.Masqueb\x06proto3"
+
+var (
+	file_proxy_masque_config_proto_rawDescOnce sync.Once
+	file_proxy_masque_config_proto_rawDescData []byte
+)
+
+func file_proxy_masque_config_proto_rawDescGZIP() []byte {
+	file_proxy_masque_config_proto_rawDescOnce.Do(func() {
+		file_proxy_masque_config_proto_rawDescData = protoimpl.X.CompressGZIP(unsafe.Slice(unsafe.StringData(file_proxy_masque_config_proto_rawDesc), len(file_proxy_masque_config_proto_rawDesc)))
+	})
+	return file_proxy_masque_config_proto_rawDescData
+}
+
+var file_proxy_masque_config_proto_msgTypes = make([]protoimpl.MessageInfo, 3)
+var file_proxy_masque_config_proto_goTypes = []any{
+	(*ClientConfig)(nil),            // 0: xray.proxy.masque.ClientConfig
+	(*Account)(nil),                 // 1: xray.proxy.masque.Account
+	(*ServerConfig)(nil),            // 2: xray.proxy.masque.ServerConfig
+	(*protocol.ServerEndpoint)(nil), // 3: xray.common.protocol.ServerEndpoint
+	(*protocol.User)(nil),           // 4: xray.common.protocol.User
+}
+var file_proxy_masque_config_proto_depIdxs = []int32{
+	3, // 0: xray.proxy.masque.ClientConfig.server:type_name -> xray.common.protocol.ServerEndpoint
+	4, // 1: xray.proxy.masque.ServerConfig.users:type_name -> xray.common.protocol.User
+	2, // [2:2] is the sub-list for method output_type
+	2, // [2:2] is the sub-list for method input_type
+	2, // [2:2] is the sub-list for extension type_name
+	2, // [2:2] is the sub-list for extension extendee
+	0, // [0:2] is the sub-list for field type_name
+}
+
+func init() { file_proxy_masque_config_proto_init() }
+func file_proxy_masque_config_proto_init() {
+	if File_proxy_masque_config_proto != nil {
+		return
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: unsafe.Slice(unsafe.StringData(file_proxy_masque_config_proto_rawDesc), len(file_proxy_masque_config_proto_rawDesc)),
+			NumEnums:      0,
+			NumMessages:   3,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_proxy_masque_config_proto_goTypes,
+		DependencyIndexes: file_proxy_masque_config_proto_depIdxs,
+		MessageInfos:      file_proxy_masque_config_proto_msgTypes,
+	}.Build()
+	File_proxy_masque_config_proto = out.File
+	file_proxy_masque_config_proto_goTypes = nil
+	file_proxy_masque_config_proto_depIdxs = nil
+}

proxy/masque/config.proto

@@ -0,0 +1,25 @@
+syntax = "proto3";
+
+package xray.proxy.masque;
+option csharp_namespace = "Xray.Proxy.Masque";
+option go_package = "github.com/xtls/xray-core/proxy/masque";
+option java_package = "com.xray.proxy.masque";
+option java_multiple_files = true;
+
+import "common/protocol/server_spec.proto";
+import "common/protocol/user.proto";
+
+message ClientConfig {
+  xray.common.protocol.ServerEndpoint server = 1;
+  repeated string remote_dns = 2;
+}
+
+message Account {
+  string password = 1;
+}
+
+message ServerConfig {
+  repeated xray.common.protocol.User users = 1;
+  repeated string address = 2;
+  uint32 mtu = 3;
+}

proxy/masque/pool.go

@@ -0,0 +1,80 @@
+package masque
+
+import (
+	"net/netip"
+	"sync"
+
+	"github.com/xtls/xray-core/common/errors"
+)
+
+type addressPool struct {
+	mu     sync.Mutex
+	prefix netip.Prefix
+	server netip.Addr
+	first  netip.Addr
+	last   netip.Addr
+	next   netip.Addr
+	used   map[netip.Addr]struct{}
+}
+
+func newAddressPool(address netip.Prefix) (*addressPool, error) {
+	server := address.Addr()
+	if server.Is4In6() || server.Zone() != "" {
+		return nil, errors.New("invalid address ", address)
+	}
+	prefix := address.Masked()
+	last := lastAddr(prefix)
+	if server == prefix.Addr() || server.Is4() && server == last {
+		return nil, errors.New("address ", address, " is not a host address")
+	}
+	if server.Is4() {
+		last = last.Prev()
+	}
+	first := prefix.Addr().Next()
+	if first == last {
+		return nil, errors.New("address ", address, " leaves no addresses to assign")
+	}
+	return &addressPool{
+		prefix: prefix,
+		server: server,
+		first:  first,
+		last:   last,
+		next:   first,
+		used:   make(map[netip.Addr]struct{}),
+	}, nil
+}
+
+func lastAddr(prefix netip.Prefix) netip.Addr {
+	b := prefix.Addr().AsSlice()
+	for i := prefix.Bits(); i < len(b)*8; i++ {
+		b[i/8] |= 1 << (7 - i%8)
+	}
+	addr, _ := netip.AddrFromSlice(b)
+	return addr
+}
+
+func (p *addressPool) allocate() (netip.Addr, bool) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	for addr := p.next; ; {
+		next := addr.Next()
+		if addr == p.last {
+			next = p.first
+		}
+		if _, found := p.used[addr]; !found && addr != p.server {
+			p.used[addr] = struct{}{}
+			p.next = next
+			return addr, true
+		}
+		if next == p.next {
+			return netip.Addr{}, false
+		}
+		addr = next
+	}
+}
+
+func (p *addressPool) release(addr netip.Addr) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	delete(p.used, addr)
+}

proxy/masque/pool_test.go

@@ -0,0 +1,59 @@
+package masque
+
+import (
+	"net/netip"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func allocateAll(p *addressPool) []netip.Addr {
+	var addrs []netip.Addr
+	for {
+		addr, ok := p.allocate()
+		if !ok {
+			return addrs
+		}
+		addrs = append(addrs, addr)
+	}
+}
+
+func TestAddressPool(t *testing.T) {
+	p, err := newAddressPool(netip.MustParsePrefix("10.0.0.1/29"))
+	require.NoError(t, err)
+	var want []netip.Addr
+	for _, s := range []string{"10.0.0.2", "10.0.0.3", "10.0.0.4", "10.0.0.5", "10.0.0.6"} {
+		want = append(want, netip.MustParseAddr(s))
+	}
+	require.Equal(t, want, allocateAll(p))
+
+	p.release(netip.MustParseAddr("10.0.0.4"))
+	addr, ok := p.allocate()
+	require.True(t, ok)
+	require.Equal(t, netip.MustParseAddr("10.0.0.4"), addr)
+	_, ok = p.allocate()
+	require.False(t, ok)
+
+	p, err = newAddressPool(netip.MustParsePrefix("fd00::1/126"))
+	require.NoError(t, err)
+	require.Equal(t, []netip.Addr{netip.MustParseAddr("fd00::2"), netip.MustParseAddr("fd00::3")}, allocateAll(p))
+
+	p, err = newAddressPool(netip.MustParsePrefix("10.0.0.2/30"))
+	require.NoError(t, err)
+	require.Equal(t, []netip.Addr{netip.MustParseAddr("10.0.0.1")}, allocateAll(p))
+}
+
+func TestAddressPoolRejects(t *testing.T) {
+	for _, s := range []string{
+		"10.0.0.0/24",
+		"10.0.0.255/24",
+		"10.0.0.1/31",
+		"10.0.0.1/32",
+		"fd00::1/127",
+		"fd00::1/128",
+		"::ffff:10.0.0.1/120",
+	} {
+		_, err := newAddressPool(netip.MustParsePrefix(s))
+		require.Error(t, err, s)
+	}
+}

proxy/masque/server.go

@@ -0,0 +1,550 @@
+package masque
+
+import (
+	"context"
+	go_errors "errors"
+	"io"
+	stdnet "net"
+	"net/http"
+	"net/netip"
+	"slices"
+	"sync"
+
+	"golang.zx2c4.com/wireguard/tun"
+
+	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/buf"
+	c "github.com/xtls/xray-core/common/ctx"
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/log"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/common/protocol"
+	"github.com/xtls/xray-core/common/session"
+	"github.com/xtls/xray-core/core"
+	"github.com/xtls/xray-core/features/routing"
+	"github.com/xtls/xray-core/proxy/wireguard"
+	"github.com/xtls/xray-core/transport"
+	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/masque"
+	"github.com/xtls/xray-core/transport/internet/masque/connectip"
+	"github.com/xtls/xray-core/transport/internet/stat"
+	"github.com/xtls/xray-core/transport/internet/tls"
+)
+
+const (
+	authenticateHeader = `Basic realm="masque", charset="UTF-8"`
+	tunnelQueueSize    = 512
+)
+
+type Server struct {
+	validator  *validator
+	dispatcher routing.Dispatcher
+	ctx        context.Context
+	tag        string
+	sniffing   session.SniffingRequest
+	mtu        int
+
+	dev   tun.Device
+	pools []*addressPool
+	local []netip.Addr
+
+	mu      sync.RWMutex
+	tunnels map[netip.Addr]*serverTunnel
+	closed  bool
+	started bool
+}
+
+type serverTunnel struct {
+	conn   stat.Connection
+	ipConn *connectip.Conn
+	user   *protocol.MemoryUser
+	addrs  []netip.Addr
+	queue  chan *buf.Buffer
+	done   chan struct{}
+
+	mu    sync.Mutex
+	conns map[net.Conn]struct{}
+}
+
+func newServerTunnel(conn stat.Connection, user *protocol.MemoryUser) *serverTunnel {
+	return &serverTunnel{
+		conn:  conn,
+		user:  user,
+		queue: make(chan *buf.Buffer, tunnelQueueSize),
+		done:  make(chan struct{}),
+		conns: make(map[net.Conn]struct{}),
+	}
+}
+
+func (t *serverTunnel) send(b *buf.Buffer) bool {
+	select {
+	case <-t.done:
+		return false
+	default:
+	}
+	select {
+	case t.queue <- b:
+		return true
+	default:
+		return false
+	}
+}
+
+func (t *serverTunnel) track(conn net.Conn) bool {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if t.conns == nil {
+		return false
+	}
+	t.conns[conn] = struct{}{}
+	return true
+}
+
+func (t *serverTunnel) untrack(conn net.Conn) {
+	t.mu.Lock()
+	delete(t.conns, conn)
+	t.mu.Unlock()
+}
+
+func (t *serverTunnel) close() {
+	t.mu.Lock()
+	conns := t.conns
+	if conns != nil {
+		t.conns = nil
+		close(t.done)
+	}
+	t.mu.Unlock()
+	for conn := range conns {
+		conn.Close()
+	}
+}
+
+func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) {
+	v := core.MustFromContext(ctx)
+
+	streamSettings := session.StreamSettingsFromContext(ctx).(*internet.MemoryStreamConfig)
+	if _, ok := streamSettings.ProtocolSettings.(*masque.Config); !ok {
+		return nil, errors.New("not masque transport")
+	}
+	if tls.ConfigFromStreamSettings(streamSettings) == nil {
+		return nil, errors.New(`MASQUE requires "security": "tls"`)
+	}
+
+	users := newValidator()
+	for _, user := range config.Users {
+		u, err := user.ToMemoryUser()
+		if err != nil {
+			return nil, errors.New("failed to get MASQUE user").Base(err)
+		}
+		if err := users.add(u); err != nil {
+			return nil, errors.New("failed to add user").Base(err)
+		}
+	}
+
+	var pools []*addressPool
+	var local []netip.Addr
+	for _, s := range config.Address {
+		prefix, err := netip.ParsePrefix(s)
+		if err != nil {
+			return nil, errors.New("invalid address ", s).Base(err)
+		}
+		if slices.ContainsFunc(local, func(addr netip.Addr) bool { return addr.Is4() == prefix.Addr().Is4() }) {
+			return nil, errors.New("only one address per IP family is supported")
+		}
+		pool, err := newAddressPool(prefix)
+		if err != nil {
+			return nil, err
+		}
+		pools = append(pools, pool)
+		local = append(local, prefix.Addr())
+	}
+	if len(pools) == 0 {
+		return nil, errors.New("no address to assign")
+	}
+
+	mtu := int(config.Mtu)
+	if mtu == 0 {
+		mtu = masque.MinPacketSize
+	}
+	dev, _, gstack, err := wireguard.CreateNetTUN(local, nil, mtu, false)
+	if err != nil {
+		return nil, err
+	}
+
+	s := &Server{
+		validator:  users,
+		dispatcher: v.GetFeature(routing.DispatcherType()).(routing.Dispatcher),
+		ctx:        core.ToBackgroundDetachedContext(ctx),
+		mtu:        mtu,
+		dev:        dev,
+		pools:      pools,
+		local:      local,
+		tunnels:    make(map[netip.Addr]*serverTunnel),
+	}
+	if inbound := session.InboundFromContext(ctx); inbound != nil {
+		s.tag = inbound.Tag
+	}
+	if content := session.ContentFromContext(ctx); content != nil {
+		s.sniffing = content.SniffingRequest
+	}
+	wireguard.CreateForwarder(gstack, s.handleConnection)
+	return s, nil
+}
+
+func (s *Server) Start() error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.started || s.closed {
+		return nil
+	}
+	s.started = true
+	go s.readFromStack()
+	return nil
+}
+
+func (s *Server) Close() error {
+	s.mu.Lock()
+	if s.closed {
+		s.mu.Unlock()
+		return nil
+	}
+	s.closed = true
+	var tunnels []*serverTunnel
+	for _, t := range s.tunnels {
+		if !slices.Contains(tunnels, t) {
+			tunnels = append(tunnels, t)
+		}
+	}
+	s.mu.Unlock()
+	for _, t := range tunnels {
+		t.conn.Close()
+	}
+	return s.dev.Close()
+}
+
+func (s *Server) AddUser(ctx context.Context, user *protocol.MemoryUser) error {
+	return s.validator.add(user)
+}
+
+func (s *Server) RemoveUser(ctx context.Context, email string) error {
+	user, err := s.validator.delByEmail(email)
+	if err != nil {
+		return err
+	}
+	s.mu.RLock()
+	var conns []stat.Connection
+	for _, t := range s.tunnels {
+		if t.user == user && !slices.Contains(conns, t.conn) {
+			conns = append(conns, t.conn)
+		}
+	}
+	s.mu.RUnlock()
+	for _, conn := range conns {
+		conn.Close()
+	}
+	return nil
+}
+
+func (s *Server) GetUser(ctx context.Context, email string) *protocol.MemoryUser {
+	return s.validator.getByEmail(email)
+}
+
+func (s *Server) GetUsers(ctx context.Context) []*protocol.MemoryUser {
+	return s.validator.getAll()
+}
+
+func (s *Server) GetUsersCount(context.Context) int64 {
+	return s.validator.count()
+}
+
+func (s *Server) Network() []net.Network {
+	return []net.Network{net.Network_TCP}
+}
+
+func (s *Server) Process(ctx context.Context, network net.Network, conn stat.Connection, dispatcher routing.Dispatcher) error {
+	sconn, ok := stat.TryUnwrapStatsConn(conn).(*masque.ServerConn)
+	if !ok {
+		return errors.New("not a MASQUE connection")
+	}
+	inbound := session.InboundFromContext(ctx)
+	inbound.Name = "masque"
+	inbound.CanSpliceCopy = 3
+
+	name, pass, _ := sconn.Request().BasicAuth()
+	user := s.validator.get(name, pass)
+	if user == nil {
+		sconn.Reject(http.StatusUnauthorized, http.Header{"WWW-Authenticate": {authenticateHeader}})
+		log.Record(&log.AccessMessage{
+			From:   conn.RemoteAddr(),
+			To:     "",
+			Status: log.AccessRejected,
+			Reason: errors.New("invalid credentials"),
+		})
+		return errors.New("MASQUE: authentication failed for ", name)
+	}
+	inbound.User = user
+
+	t := newServerTunnel(conn, user)
+	for _, pool := range s.pools {
+		if addr, ok := pool.allocate(); ok {
+			t.addrs = append(t.addrs, addr)
+		}
+	}
+	defer s.release(t)
+	if len(t.addrs) == 0 {
+		sconn.Reject(http.StatusServiceUnavailable, nil)
+		return errors.New("MASQUE: no address left to assign")
+	}
+
+	ipConn, err := sconn.Accept()
+	if err != nil {
+		return errors.New("MASQUE: failed to accept the tunnel").Base(err)
+	}
+	t.ipConn = ipConn
+	if !s.register(t) {
+		return errors.New("MASQUE: server closed")
+	}
+	if !s.validator.contains(user) {
+		return errors.New("MASQUE: user ", name, " was removed")
+	}
+	go s.writeToTunnel(t)
+
+	prefixes := make([]netip.Prefix, len(t.addrs))
+	for i, addr := range t.addrs {
+		prefixes[i] = netip.PrefixFrom(addr, addr.BitLen())
+	}
+	if err := ipConn.AssignAddresses(prefixes); err != nil {
+		return err
+	}
+	if err := ipConn.AdvertiseRoute(fullRoutes(t.addrs)); err != nil {
+		return err
+	}
+	go serveAddressRequests(t)
+
+	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
+		From:   conn.RemoteAddr(),
+		To:     "",
+		Status: log.AccessAccepted,
+		Email:  user.Email,
+	})
+	errors.LogInfo(ctx, "MASQUE: tunnel from ", inbound.Source, " assigned ", t.addrs)
+	return s.readFromTunnel(t)
+}
+
+func fullRoutes(addrs []netip.Addr) []connectip.IPRoute {
+	var routes []connectip.IPRoute
+	if slices.ContainsFunc(addrs, netip.Addr.Is4) {
+		routes = append(routes, connectip.IPRoute{StartIP: netip.IPv4Unspecified(), EndIP: netip.AddrFrom4([4]byte{255, 255, 255, 255})})
+	}
+	if slices.ContainsFunc(addrs, netip.Addr.Is6) {
+		routes = append(routes, connectip.IPRoute{StartIP: netip.IPv6Unspecified(), EndIP: netip.AddrFrom16([16]byte{0: 0xff, 1: 0xff, 2: 0xff, 3: 0xff, 4: 0xff, 5: 0xff, 6: 0xff, 7: 0xff, 8: 0xff, 9: 0xff, 10: 0xff, 11: 0xff, 12: 0xff, 13: 0xff, 14: 0xff, 15: 0xff})})
+	}
+	return routes
+}
+
+func serveAddressRequests(t *serverTunnel) {
+	for {
+		req, err := t.ipConn.ReceiveAddressRequest(context.Background())
+		if err != nil {
+			return
+		}
+		assigned := make([]netip.Prefix, len(req.Prefixes))
+		used := make(map[netip.Addr]bool)
+		for i, requested := range req.Prefixes {
+			for _, addr := range t.addrs {
+				if addr.Is4() == requested.Addr().Is4() && !used[addr] {
+					used[addr] = true
+					assigned[i] = netip.PrefixFrom(addr, addr.BitLen())
+					break
+				}
+			}
+		}
+		var additional []netip.Prefix
+		for _, addr := range t.addrs {
+			if !used[addr] {
+				additional = append(additional, netip.PrefixFrom(addr, addr.BitLen()))
+			}
+		}
+		if err := req.Respond(assigned, additional); err != nil {
+			return
+		}
+	}
+}
+
+func (s *Server) register(t *serverTunnel) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.closed {
+		return false
+	}
+	for _, addr := range t.addrs {
+		s.tunnels[addr] = t
+	}
+	return true
+}
+
+func (s *Server) release(t *serverTunnel) {
+	s.mu.Lock()
+	for _, addr := range t.addrs {
+		if s.tunnels[addr] == t {
+			delete(s.tunnels, addr)
+		}
+	}
+	s.mu.Unlock()
+	t.close()
+	for _, addr := range t.addrs {
+		for _, pool := range s.pools {
+			if pool.prefix.Contains(addr) {
+				pool.release(addr)
+			}
+		}
+	}
+}
+
+func (s *Server) lookup(addr netip.Addr) *serverTunnel {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.tunnels[addr]
+}
+
+func (s *Server) inPool(addr netip.Addr) bool {
+	return slices.ContainsFunc(s.pools, func(pool *addressPool) bool { return pool.prefix.Contains(addr) })
+}
+
+func (s *Server) readFromTunnel(t *serverTunnel) error {
+	b := make([]byte, 1<<16)
+	for {
+		n, err := t.conn.Read(b)
+		if err != nil {
+			if go_errors.Is(err, io.ErrShortBuffer) {
+				continue
+			}
+			if go_errors.Is(err, stdnet.ErrClosed) || go_errors.Is(err, io.EOF) {
+				return nil
+			}
+			return err
+		}
+		dst, ok := packetDestination(b[:n])
+		if !ok || dst.IsLinkLocalUnicast() || dst.IsMulticast() {
+			continue
+		}
+		if other := s.lookup(dst); other != nil {
+			if other != t {
+				packet := buf.NewWithSize(int32(n))
+				packet.Write(b[:n])
+				if !other.send(packet) {
+					packet.Release()
+				}
+			}
+			continue
+		}
+		if s.inPool(dst) && !slices.Contains(s.local, dst) {
+			continue
+		}
+		s.dev.Write([][]byte{b[:n]}, 0)
+	}
+}
+
+func (s *Server) readFromStack() {
+	sizes := []int{0}
+	var b *buf.Buffer
+	for {
+		if b == nil {
+			b = buf.NewWithSize(int32(s.mtu))
+		}
+		b.Clear()
+		if _, err := s.dev.Read([][]byte{b.Extend(int32(s.mtu))}, sizes, 0); err != nil {
+			b.Release()
+			return
+		}
+		b.Resize(0, int32(sizes[0]))
+		dst, ok := packetDestination(b.Bytes())
+		if !ok {
+			continue
+		}
+		if t := s.lookup(dst); t != nil && t.send(b) {
+			b = nil
+		}
+	}
+}
+
+func (s *Server) writeToTunnel(t *serverTunnel) {
+	for {
+		select {
+		case b := <-t.queue:
+			_, err := t.conn.Write(b.Bytes())
+			b.Release()
+			if ptb, ok := go_errors.AsType[*masque.PacketTooBigError](err); ok {
+				s.dev.Write([][]byte{ptb.ICMP}, 0)
+			}
+		case <-t.done:
+			return
+		}
+	}
+}
+
+func packetDestination(packet []byte) (netip.Addr, bool) {
+	if len(packet) == 0 {
+		return netip.Addr{}, false
+	}
+	switch packet[0] >> 4 {
+	case 4:
+		if len(packet) >= 20 {
+			return netip.AddrFrom4([4]byte(packet[16:20])), true
+		}
+	case 6:
+		if len(packet) >= 40 {
+			return netip.AddrFrom16([16]byte(packet[24:40])), true
+		}
+	}
+	return netip.Addr{}, false
+}
+
+func (s *Server) handleConnection(conn net.Conn, dest net.Destination) {
+	defer conn.Close()
+	source := net.DestinationFromAddr(conn.RemoteAddr())
+	addr, _ := netip.AddrFromSlice(source.Address.IP())
+	t := s.lookup(addr.Unmap())
+	if t == nil || !t.track(conn) {
+		errors.LogInfo(s.ctx, "MASQUE: no tunnel for ", source, " to ", dest)
+		return
+	}
+	defer t.untrack(conn)
+
+	ctx, cancel := context.WithCancel(s.ctx)
+	defer cancel()
+	ctx = c.ContextWithID(ctx, session.NewID())
+	inbound := session.Inbound{
+		Name:          "masque",
+		Tag:           s.tag,
+		CanSpliceCopy: 3,
+		Source:        source,
+		User:          t.user,
+	}
+	ctx = session.ContextWithInbound(ctx, &inbound)
+	ctx = session.ContextWithContent(ctx, &session.Content{
+		SniffingRequest: s.sniffing,
+	})
+	ctx = session.SubContextFromMuxInbound(ctx)
+	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
+		From:   source,
+		To:     dest,
+		Status: log.AccessAccepted,
+		Email:  t.user.Email,
+	})
+	errors.LogInfo(ctx, "processing from ", source, " to ", dest)
+
+	link := &transport.Link{
+		Reader: &buf.TimeoutWrapperReader{Reader: buf.NewReader(conn)},
+		Writer: buf.NewWriter(conn),
+	}
+	if err := s.dispatcher.DispatchLink(ctx, dest, link); err != nil {
+		errors.LogError(ctx, errors.New("connection closed").Base(err))
+	}
+}
+
+func init() {
+	common.Must(common.RegisterConfig((*ServerConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
+		return NewServer(ctx, config.(*ServerConfig))
+	}))
+}

proxy/masque/server_test.go

@@ -0,0 +1,328 @@
+package masque
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"net/netip"
+	"os"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+	"github.com/xtls/xray-core/common/buf"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/common/protocol"
+	"golang.zx2c4.com/wireguard/tun"
+)
+
+type fakeTunnelConn struct {
+	mu      sync.Mutex
+	reads   chan []byte
+	written [][]byte
+	closed  bool
+	stall   chan struct{}
+}
+
+func newFakeTunnelConn() *fakeTunnelConn {
+	return &fakeTunnelConn{reads: make(chan []byte, 16)}
+}
+
+func (c *fakeTunnelConn) Read(b []byte) (int, error) {
+	p, ok := <-c.reads
+	if !ok {
+		return 0, io.EOF
+	}
+	return copy(b, p), nil
+}
+
+func (c *fakeTunnelConn) Write(b []byte) (int, error) {
+	if c.stall != nil {
+		<-c.stall
+	}
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.written = append(c.written, bytes.Clone(b))
+	return len(b), nil
+}
+
+func (c *fakeTunnelConn) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if !c.closed {
+		c.closed = true
+		close(c.reads)
+	}
+	return nil
+}
+
+func (c *fakeTunnelConn) packets() [][]byte {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.written
+}
+
+func (c *fakeTunnelConn) isClosed() bool {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.closed
+}
+
+func (c *fakeTunnelConn) LocalAddr() net.Addr                { return &net.TCPAddr{} }
+func (c *fakeTunnelConn) RemoteAddr() net.Addr               { return &net.TCPAddr{} }
+func (c *fakeTunnelConn) SetDeadline(t time.Time) error      { return nil }
+func (c *fakeTunnelConn) SetReadDeadline(t time.Time) error  { return nil }
+func (c *fakeTunnelConn) SetWriteDeadline(t time.Time) error { return nil }
+
+type fakeDevice struct {
+	mu      sync.Mutex
+	reads   chan []byte
+	written [][]byte
+	closed  bool
+}
+
+func (d *fakeDevice) File() *os.File           { return nil }
+func (d *fakeDevice) MTU() (int, error)        { return 1280, nil }
+func (d *fakeDevice) Name() (string, error)    { return "fake", nil }
+func (d *fakeDevice) Events() <-chan tun.Event { return nil }
+func (d *fakeDevice) BatchSize() int           { return 1 }
+
+func (d *fakeDevice) Read(bufs [][]byte, sizes []int, offset int) (int, error) {
+	p, ok := <-d.reads
+	if !ok {
+		return 0, os.ErrClosed
+	}
+	sizes[0] = copy(bufs[0][offset:], p)
+	return 1, nil
+}
+
+func (d *fakeDevice) Write(bufs [][]byte, offset int) (int, error) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	for _, b := range bufs {
+		d.written = append(d.written, bytes.Clone(b[offset:]))
+	}
+	return len(bufs), nil
+}
+
+func (d *fakeDevice) Close() error {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	if !d.closed {
+		d.closed = true
+		close(d.reads)
+	}
+	return nil
+}
+
+func (d *fakeDevice) packets() [][]byte {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	return d.written
+}
+
+func ipPacket(src, dst string) []byte {
+	s, d := netip.MustParseAddr(src), netip.MustParseAddr(dst)
+	if s.Is4() {
+		b := make([]byte, 20)
+		b[0] = 0x45
+		b[8] = 64
+		copy(b[12:16], s.AsSlice())
+		copy(b[16:20], d.AsSlice())
+		return b
+	}
+	b := make([]byte, 40)
+	b[0] = 0x60
+	b[7] = 64
+	copy(b[8:24], s.AsSlice())
+	copy(b[24:40], d.AsSlice())
+	return b
+}
+
+func newTestServer(t *testing.T) (*Server, *fakeDevice) {
+	t.Helper()
+	pool4, err := newAddressPool(netip.MustParsePrefix("10.14.0.1/24"))
+	require.NoError(t, err)
+	pool6, err := newAddressPool(netip.MustParsePrefix("fd14::1/64"))
+	require.NoError(t, err)
+	dev := &fakeDevice{reads: make(chan []byte, tunnelQueueSize*2)}
+	s := &Server{
+		mtu:     1280,
+		dev:     dev,
+		pools:   []*addressPool{pool4, pool6},
+		local:   []netip.Addr{netip.MustParseAddr("10.14.0.1"), netip.MustParseAddr("fd14::1")},
+		tunnels: make(map[netip.Addr]*serverTunnel),
+	}
+	return s, dev
+}
+
+func addTunnel(t *testing.T, s *Server) (*serverTunnel, *fakeTunnelConn) {
+	t.Helper()
+	return addUserTunnel(t, s, &protocol.MemoryUser{})
+}
+
+func addUserTunnel(t *testing.T, s *Server, user *protocol.MemoryUser) (*serverTunnel, *fakeTunnelConn) {
+	t.Helper()
+	conn := newFakeTunnelConn()
+	tunnel := newServerTunnel(conn, user)
+	for _, pool := range s.pools {
+		addr, ok := pool.allocate()
+		require.True(t, ok)
+		tunnel.addrs = append(tunnel.addrs, addr)
+	}
+	require.True(t, s.register(tunnel))
+	go s.writeToTunnel(tunnel)
+	t.Cleanup(tunnel.close)
+	return tunnel, conn
+}
+
+func TestServerRoutesTunnelPackets(t *testing.T) {
+	s, dev := newTestServer(t)
+	a, aConn := addTunnel(t, s)
+	b, bConn := addTunnel(t, s)
+	require.Equal(t, []netip.Addr{netip.MustParseAddr("10.14.0.2"), netip.MustParseAddr("fd14::2")}, a.addrs)
+	require.Equal(t, []netip.Addr{netip.MustParseAddr("10.14.0.3"), netip.MustParseAddr("fd14::3")}, b.addrs)
+
+	toB := ipPacket("10.14.0.2", "10.14.0.3")
+	toB6 := ipPacket("fd14::2", "fd14::3")
+	toServer := ipPacket("10.14.0.2", "10.14.0.1")
+	toInternet := ipPacket("fd14::2", "2001:db8::1")
+	for _, p := range [][]byte{
+		toB,
+		toB6,
+		ipPacket("10.14.0.2", "10.14.0.9"),
+		ipPacket("fd14::2", "fd14::99"),
+		ipPacket("fd14::2", "fe80::1"),
+		ipPacket("fd14::2", "ff02::1"),
+		ipPacket("10.14.0.2", "224.0.0.251"),
+		ipPacket("10.14.0.2", "10.14.0.2"),
+		toServer,
+		toInternet,
+	} {
+		aConn.reads <- p
+	}
+	aConn.Close()
+	require.NoError(t, s.readFromTunnel(a))
+
+	require.Eventually(t, func() bool { return len(bConn.packets()) == 2 }, time.Second, time.Millisecond)
+	require.Equal(t, [][]byte{toB, toB6}, bConn.packets())
+	require.Equal(t, [][]byte{toServer, toInternet}, dev.packets())
+	require.Empty(t, aConn.packets())
+}
+
+func TestServerRoutesStackPackets(t *testing.T) {
+	s, dev := newTestServer(t)
+	_, aConn := addTunnel(t, s)
+	_, bConn := addTunnel(t, s)
+	require.NoError(t, s.Start())
+
+	toA := ipPacket("192.0.2.1", "10.14.0.2")
+	toB := ipPacket("2001:db8::1", "fd14::3")
+	dev.reads <- toA
+	dev.reads <- ipPacket("192.0.2.1", "10.14.0.9")
+	dev.reads <- toB
+	require.Eventually(t, func() bool {
+		return len(aConn.packets()) == 1 && len(bConn.packets()) == 1
+	}, time.Second, time.Millisecond)
+	require.Equal(t, [][]byte{toA}, aConn.packets())
+	require.Equal(t, [][]byte{toB}, bConn.packets())
+
+	require.NoError(t, s.Close())
+	require.True(t, aConn.isClosed())
+	require.True(t, bConn.isClosed())
+	require.False(t, s.register(&serverTunnel{}))
+}
+
+func TestServerSlowTunnelDoesNotBlockOthers(t *testing.T) {
+	s, dev := newTestServer(t)
+	_, aConn := addTunnel(t, s)
+	_, bConn := addTunnel(t, s)
+	aConn.stall = make(chan struct{})
+	defer close(aConn.stall)
+	require.NoError(t, s.Start())
+	defer s.Close()
+
+	for range tunnelQueueSize + 10 {
+		dev.reads <- ipPacket("192.0.2.1", "10.14.0.2")
+	}
+	toB := ipPacket("192.0.2.1", "10.14.0.3")
+	dev.reads <- toB
+	require.Eventually(t, func() bool { return len(bConn.packets()) == 1 }, time.Second, time.Millisecond)
+	require.Equal(t, [][]byte{toB}, bConn.packets())
+}
+
+func TestServerClosesTunnelConnections(t *testing.T) {
+	s, _ := newTestServer(t)
+	a, _ := addTunnel(t, s)
+	conn := newFakeTunnelConn()
+	require.True(t, a.track(conn))
+	other := newFakeTunnelConn()
+	require.True(t, a.track(other))
+	a.untrack(other)
+
+	s.release(a)
+	require.True(t, conn.isClosed())
+	require.False(t, other.isClosed())
+	require.False(t, a.track(newFakeTunnelConn()))
+	require.False(t, a.send(buf.New()))
+}
+
+func TestServerReleasesAddresses(t *testing.T) {
+	s, _ := newTestServer(t)
+	a, _ := addTunnel(t, s)
+	s.release(a)
+	require.Nil(t, s.lookup(netip.MustParseAddr("10.14.0.2")))
+	b, _ := addTunnel(t, s)
+	require.Equal(t, []netip.Addr{netip.MustParseAddr("10.14.0.3"), netip.MustParseAddr("fd14::3")}, b.addrs)
+	for range 250 {
+		addTunnel(t, s)
+	}
+	c, _ := addTunnel(t, s)
+	require.Equal(t, netip.MustParseAddr("10.14.0.254"), c.addrs[0])
+	addr, ok := s.pools[0].allocate()
+	require.True(t, ok)
+	require.Equal(t, netip.MustParseAddr("10.14.0.2"), addr)
+	_, ok = s.pools[0].allocate()
+	require.False(t, ok)
+}
+
+func TestServerRemoveUserClosesTunnels(t *testing.T) {
+	s, _ := newTestServer(t)
+	s.validator = newValidator()
+	alice := &protocol.MemoryUser{Email: "a@example.com", Account: &MemoryAccount{Password: "p"}}
+	bob := &protocol.MemoryUser{Email: "b@example.com", Account: &MemoryAccount{Password: "p"}}
+	require.NoError(t, s.AddUser(context.Background(), alice))
+	require.NoError(t, s.AddUser(context.Background(), bob))
+	_, aConn := addUserTunnel(t, s, alice)
+	_, bConn := addUserTunnel(t, s, bob)
+
+	require.NoError(t, s.RemoveUser(context.Background(), "a@example.com"))
+	require.True(t, aConn.isClosed())
+	require.False(t, bConn.isClosed())
+	require.Error(t, s.RemoveUser(context.Background(), "a@example.com"))
+	require.Nil(t, s.validator.get("a@example.com", "p"))
+	require.Equal(t, bob, s.validator.get("b@example.com", "p"))
+}
+
+func TestPacketDestination(t *testing.T) {
+	v4 := make([]byte, 20)
+	v4[0] = 0x45
+	copy(v4[16:20], []byte{192, 0, 2, 1})
+	addr, ok := packetDestination(v4)
+	require.True(t, ok)
+	require.Equal(t, netip.MustParseAddr("192.0.2.1"), addr)
+
+	v6 := make([]byte, 40)
+	v6[0] = 0x60
+	dst := netip.MustParseAddr("2001:db8::1").As16()
+	copy(v6[24:40], dst[:])
+	addr, ok = packetDestination(v6)
+	require.True(t, ok)
+	require.Equal(t, netip.MustParseAddr("2001:db8::1"), addr)
+
+	for _, b := range [][]byte{nil, v4[:19], v6[:39], {0x50}} {
+		_, ok = packetDestination(b)
+		require.False(t, ok)
+	}
+}

proxy/proxy.go

@@ -277,6 +277,7 @@ func (w *VisionReader) ReadMultiBuffer() (buf.MultiBuffer, error) {
 				w.ob.CanSpliceCopy = 1
 			}
 		}
+		SuppressOuterCloseNotify(w.conn)
 		readerConn, readCounter, _ := UnwrapRawConn(w.conn)
 		w.directReadCounter = readCounter
 		w.Reader = buf.NewReader(readerConn)
@@ -340,6 +341,7 @@ func (w *VisionWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
 			// 	w.ob.CanSpliceCopy = 1
 			// }
 		}
+		SuppressOuterCloseNotify(w.conn)
 		rawConn, _, writerCounter := UnwrapRawConn(w.conn)
 		w.Writer = buf.NewWriter(rawConn)
 		w.directWriteCounter = writerCounter
@@ -669,6 +671,19 @@ func XtlsFilterTls(buffer buf.MultiBuffer, trafficState *TrafficState, ctx conte
 	}
 }
 
+type CloseNotifySuppressor interface {
+	SuppressCloseNotify()
+}
+
+// Close our local TLS conn instance might send a incorrect close_notify alert
+// if the XTLS direct copy mode is enabled and cause TLS BAD_RECORD_MAC on users' browser
+// Close the underlying connection directly to avoid this issue.
+func SuppressOuterCloseNotify(conn net.Conn) {
+	if suppressor, ok := stat.TryUnwrapStatsConn(conn).(CloseNotifySuppressor); ok {
+		suppressor.SuppressCloseNotify()
+	}
+}
+
 // UnwrapRawConn support unwrap encryption, stats, mask wrappers, tls, utls, reality, proxyproto, uds-wrapper conn and get raw tcp/uds conn from it
 func UnwrapRawConn(conn net.Conn) (net.Conn, stats.Counter, stats.Counter) {
 	var readCounter, writerCounter stats.Counter

proxy/shadowsocks/client.go

@@ -71,7 +71,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 		return nil
 	})
 	if err != nil {
-		return errors.New("failed to find an available destination").AtWarning().Base(err)
+		return errors.New("failed to find an available destination").Base(err)
 	}
 	errors.LogInfo(ctx, "tunneling request to ", destination, " via ", network, ":", server.Destination.NetAddr())
 
@@ -124,7 +124,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 			}
 
 			if err = buf.CopyOnceTimeout(link.Reader, bodyWriter, time.Millisecond*100); err != nil && err != buf.ErrNotTimeoutReader && err != buf.ErrReadTimeout {
-				return errors.New("failed to write A request payload").Base(err).AtWarning()
+				return errors.New("failed to write A request payload").Base(err)
 			}
 
 			if err := bufferedWriter.SetBuffered(false); err != nil {

proxy/shadowsocks/protocol.go

@@ -98,7 +98,7 @@ func ReadTCPSession(validator *Validator, reader io.Reader) (*protocol.RequestHe
 			iv := append([]byte(nil), buffer.BytesTo(ivLen)...)
 			r, err = account.Cipher.NewDecryptionReader(account.Key, iv, reader)
 			if err != nil {
-				return nil, nil, drain.WithError(drainer, reader, errors.New("failed to initialize decoding stream").Base(err).AtError())
+				return nil, nil, drain.WithError(drainer, reader, errors.New("failed to initialize decoding stream").Base(err))
 			}
 		}
 	}
@@ -146,7 +146,7 @@ func WriteTCPRequest(request *protocol.RequestHeader, writer io.Writer) (buf.Wri
 
 	w, err := account.Cipher.NewEncryptionWriter(account.Key, iv, writer)
 	if err != nil {
-		return nil, errors.New("failed to create encoding stream").Base(err).AtError()
+		return nil, errors.New("failed to create encoding stream").Base(err)
 	}
 
 	header := buf.New()

proxy/shadowsocks/server.go

@@ -34,11 +34,11 @@ func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) {
 	for _, user := range config.Users {
 		u, err := user.ToMemoryUser()
 		if err != nil {
-			return nil, errors.New("failed to get shadowsocks user").Base(err).AtError()
+			return nil, errors.New("failed to get shadowsocks user").Base(err)
 		}
 
 		if err := validator.Add(u); err != nil {
-			return nil, errors.New("failed to add user").Base(err).AtError()
+			return nil, errors.New("failed to add user").Base(err)
 		}
 	}
 
@@ -200,7 +200,7 @@ func (s *Server) handleUDPPayload(ctx context.Context, conn stat.Connection, dis
 func (s *Server) handleConnection(ctx context.Context, conn stat.Connection, dispatcher routing.Dispatcher) error {
 	sessionPolicy := s.policyManager.ForLevel(0)
 	if err := conn.SetReadDeadline(time.Now().Add(sessionPolicy.Timeouts.Handshake)); err != nil {
-		return errors.New("unable to set read deadline").Base(err).AtWarning()
+		return errors.New("unable to set read deadline").Base(err)
 	}
 
 	bufferedReader := buf.BufferedReader{Reader: buf.NewReader(conn)}

proxy/shadowsocks_2022/cipher.go

@@ -0,0 +1,55 @@
+package shadowsocks_2022
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"errors"
+	"strings"
+
+	"golang.org/x/crypto/chacha20poly1305"
+)
+
+type CipherMethod struct {
+	Name          string
+	KeySaltLength int
+	IsChaCha      bool
+}
+
+var methods = map[string]*CipherMethod{
+	MethodAES128GCM:        {Name: MethodAES128GCM, KeySaltLength: 16, IsChaCha: false},
+	MethodAES256GCM:        {Name: MethodAES256GCM, KeySaltLength: 32, IsChaCha: false},
+	MethodChaCha20Poly1305: {Name: MethodChaCha20Poly1305, KeySaltLength: 32, IsChaCha: true},
+}
+
+func GetCipherMethod(name string) (*CipherMethod, error) {
+	name = strings.ToLower(name)
+	if m, ok := methods[name]; ok {
+		return m, nil
+	}
+	return nil, errors.New("unknown shadowsocks 2022 method")
+}
+
+// NewAEAD creates standard stream AEAD cipher instance (AES-GCM or ChaCha20-Poly1305)
+func (m *CipherMethod) NewAEAD(key []byte) (cipher.AEAD, error) {
+	if m.IsChaCha {
+		return chacha20poly1305.New(key)
+	}
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	return cipher.NewGCM(block)
+}
+
+// NewBlock creates standard 16-byte block cipher for AES header encryption/decryption
+func (m *CipherMethod) NewBlock(key []byte) (cipher.Block, error) {
+	return aes.NewCipher(key)
+}
+
+// NewUDPCipher creates AEAD cipher for UDP packets (XChaCha20-Poly1305 with 24-byte nonce)
+func (m *CipherMethod) NewUDPCipher(key []byte) (cipher.AEAD, error) {
+	if m.IsChaCha {
+		return chacha20poly1305.NewX(key)
+	}
+	return nil, errors.New("shadowsocks-2022: udp separate AEAD cipher only available for chacha20 method")
+}

proxy/shadowsocks_2022/config.go

@@ -1,6 +1,9 @@
 package shadowsocks_2022
 
 import (
+	"bytes"
+	"encoding/base64"
+
 	"google.golang.org/protobuf/proto"
 
 	"github.com/xtls/xray-core/common/protocol"
@@ -8,26 +11,31 @@ import (
 
 // MemoryAccount is an account type converted from Account.
 type MemoryAccount struct {
-	Key string
+	Key []byte
 }
 
 // AsAccount implements protocol.AsAccount.
 func (u *Account) AsAccount() (protocol.Account, error) {
+	keyStr := u.GetKey()
+	raw, err := base64.StdEncoding.DecodeString(keyStr)
+	if err != nil {
+		raw = []byte(keyStr)
+	}
 	return &MemoryAccount{
-		Key: u.GetKey(),
+		Key: raw,
 	}, nil
 }
 
 // Equals implements protocol.Account.Equals().
 func (a *MemoryAccount) Equals(another protocol.Account) bool {
 	if account, ok := another.(*MemoryAccount); ok {
-		return a.Key == account.Key
+		return bytes.Equal(a.Key, account.Key)
 	}
 	return false
 }
 
 func (a *MemoryAccount) ToProto() proto.Message {
 	return &Account{
-		Key: a.Key,
+		Key: base64.StdEncoding.EncodeToString(a.Key),
 	}
 }

proxy/shadowsocks_2022/inbound.go

@@ -2,17 +2,11 @@ package shadowsocks_2022
 
 import (
 	"context"
+	"io"
 	"time"
 
-	shadowsocks "github.com/sagernet/sing-shadowsocks"
-	"github.com/sagernet/sing-shadowsocks/shadowaead_2022"
-	C "github.com/sagernet/sing/common"
-	B "github.com/sagernet/sing/common/buf"
-	"github.com/sagernet/sing/common/bufio"
-	E "github.com/sagernet/sing/common/exceptions"
-	M "github.com/sagernet/sing/common/metadata"
-	N "github.com/sagernet/sing/common/network"
 	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/antireplay"
 	"github.com/xtls/xray-core/common/buf"
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/log"
@@ -20,7 +14,10 @@ import (
 	"github.com/xtls/xray-core/common/protocol"
 	"github.com/xtls/xray-core/common/session"
 	"github.com/xtls/xray-core/common/signal"
-	"github.com/xtls/xray-core/common/singbridge"
+	"github.com/xtls/xray-core/common/task"
+	"github.com/xtls/xray-core/common/utils"
+	"github.com/xtls/xray-core/core"
+	"github.com/xtls/xray-core/features/policy"
 	"github.com/xtls/xray-core/features/routing"
 	"github.com/xtls/xray-core/transport/internet/stat"
 )
@@ -32,10 +29,13 @@ func init() {
 }
 
 type Inbound struct {
-	networks []net.Network
-	service  shadowsocks.Service
-	email    string
-	level    int
+	networks      []net.Network
+	method        *CipherMethod
+	psk           []byte
+	user          *protocol.MemoryUser
+	saltFilter    *antireplay.ReplayFilter[[32]byte]
+	udpCodec      *UDPServerCodec
+	policyManager policy.Manager
 }
 
 func NewServer(ctx context.Context, config *ServerConfig) (*Inbound, error) {
@@ -46,20 +46,35 @@ func NewServer(ctx context.Context, config *ServerConfig) (*Inbound, error) {
 			net.Network_UDP,
 		}
 	}
-	inbound := &Inbound{
-		networks: networks,
-		email:    config.Email,
-		level:    int(config.Level),
-	}
-	if !C.Contains(shadowaead_2022.List, config.Method) {
-		return nil, errors.New("unsupported method ", config.Method)
-	}
-	service, err := shadowaead_2022.NewServiceWithPassword(config.Method, config.Key, 500, inbound, nil)
+
+	method, err := GetCipherMethod(config.Method)
 	if err != nil {
-		return nil, errors.New("create service").Base(err)
+		return nil, errors.New("unsupported method: ", config.Method).Base(err)
 	}
-	inbound.service = service
-	return inbound, nil
+
+	psk, err := ParseKey(config.Key, method.KeySaltLength)
+	if err != nil {
+		return nil, err
+	}
+
+	udpCodec, err := NewUDPServerCodec(method, psk, 500*time.Second)
+	if err != nil {
+		return nil, err
+	}
+
+	v := core.MustFromContext(ctx)
+	return &Inbound{
+		networks:   networks,
+		method:     method,
+		psk:        psk,
+		saltFilter: antireplay.NewMapFilter[[32]byte](60),
+		user: &protocol.MemoryUser{
+			Email: config.Email,
+			Level: uint32(config.Level),
+		},
+		udpCodec:      udpCodec,
+		policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager),
+	}, nil
 }
 
 func (i *Inbound) Network() []net.Network {
@@ -70,114 +85,181 @@ func (i *Inbound) Process(ctx context.Context, network net.Network, connection s
 	inbound := session.InboundFromContext(ctx)
 	inbound.Name = "shadowsocks-2022"
 	inbound.CanSpliceCopy = 3
-
-	var metadata M.Metadata
-	if inbound.Source.IsValid() {
-		metadata.Source = M.ParseSocksaddr(inbound.Source.NetAddr())
-	}
-
-	ctx = session.ContextWithDispatcher(ctx, dispatcher)
+	inbound.User = i.user
 
 	if network == net.Network_TCP {
-		return singbridge.ReturnError(i.service.NewConnection(ctx, connection, metadata))
-	} else {
-		reader := buf.NewReader(connection)
-		pc := &natPacketConn{connection}
-		for {
-			mb, err := reader.ReadMultiBuffer()
+		return i.processTCP(ctx, connection, dispatcher)
+	}
+	return i.processUDP(ctx, connection, dispatcher)
+}
+
+func (i *Inbound) processTCP(ctx context.Context, conn net.Conn, dispatcher routing.Dispatcher) error {
+	defer conn.Close()
+
+	sessionPolicy := i.policyManager.ForLevel(0)
+	if err := conn.SetReadDeadline(time.Now().Add(sessionPolicy.Timeouts.Handshake)); err != nil {
+		return errors.New("unable to set read deadline").Base(err)
+	}
+
+	var salt [32]byte
+	saltSlice := salt[:i.method.KeySaltLength]
+	if _, err := io.ReadFull(conn, saltSlice); err != nil {
+		return err
+	}
+
+	if !i.saltFilter.Check(salt) {
+		return ErrSaltNotUnique
+	}
+
+	sessionKey := DeriveSessionSubKey(i.psk, saltSlice, i.method.KeySaltLength)
+	aead, err := i.method.NewAEAD(sessionKey)
+	if err != nil {
+		return err
+	}
+
+	reader := NewStreamReader(conn, aead)
+
+	reqHeader, err := ReadClientRequestHeader(conn, reader)
+	if err != nil {
+		return err
+	}
+	conn.SetReadDeadline(time.Time{})
+	dest := reqHeader.Destination
+
+	writer, err := WriteTCPResponse(conn, i.method, i.psk, saltSlice, nil)
+	if err != nil {
+		return err
+	}
+
+	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
+		From:   conn.RemoteAddr(),
+		To:     dest,
+		Status: log.AccessAccepted,
+		Email:  i.user.Email,
+	})
+
+	errors.LogInfo(ctx, "tunneling request to ", dest)
+
+	link, err := dispatcher.Dispatch(ctx, dest)
+	if err != nil {
+		return err
+	}
+
+	if len(reqHeader.EarlyData) > 0 {
+		earlyBuf := buf.New()
+		earlyBuf.Write(reqHeader.EarlyData)
+		if err := link.Writer.WriteMultiBuffer(buf.MultiBuffer{earlyBuf}); err != nil {
+			return err
+		}
+	}
+
+	sessionPolicy = i.policyManager.ForLevel(uint32(i.user.Level))
+	ctx, cancel := context.WithCancel(ctx)
+	timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle)
+	ctx = policy.ContextWithBufferPolicy(ctx, sessionPolicy.Buffer)
+
+	requestDone := func() error {
+		defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
+		return buf.Copy(reader, link.Writer, buf.UpdateActivity(timer))
+	}
+
+	responseDone := func() error {
+		defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
+		return buf.Copy(link.Reader, writer, buf.UpdateActivity(timer))
+	}
+
+	responseDoneAndCloseWriter := task.OnSuccess(responseDone, task.Close(link.Writer))
+	return task.Run(ctx, requestDone, responseDoneAndCloseWriter)
+}
+
+func (i *Inbound) processUDP(ctx context.Context, conn stat.Connection, dispatcher routing.Dispatcher) error {
+	udpConns := utils.NewTypedSyncMap[uint64, *udpConnEntry]()
+	defer func() {
+		udpConns.Range(func(key uint64, entry *udpConnEntry) bool {
+			entry.timer.SetTimeout(0)
+			return true
+		})
+	}()
+
+	reader := buf.NewReader(conn)
+	for {
+		mb, err := reader.ReadMultiBuffer()
+		if err != nil {
+			buf.ReleaseMulti(mb)
+			return err
+		}
+
+		for _, b := range mb {
+			decoded, err := i.udpCodec.DecodePacket(b.Bytes())
 			if err != nil {
-				buf.ReleaseMulti(mb)
-				return singbridge.ReturnError(err)
+				b.Release()
+				continue
 			}
-			for _, buffer := range mb {
-				packet := B.As(buffer.Bytes()).ToOwned()
-				buffer.Release()
-				err = i.service.NewPacket(ctx, pc, packet, metadata)
+
+			entry, ok := udpConns.Load(decoded.SessionID)
+			if !ok {
+				sessCtx, cancel := context.WithCancel(ctx)
+				sessCtx = log.ContextWithAccessMessage(sessCtx, &log.AccessMessage{
+					From:   conn.RemoteAddr(),
+					To:     decoded.Destination,
+					Status: log.AccessAccepted,
+					Email:  i.user.Email,
+				})
+
+				link, err := dispatcher.Dispatch(sessCtx, decoded.Destination)
 				if err != nil {
-					packet.Release()
-					buf.ReleaseMulti(mb)
-					return err
+					cancel()
+					b.Release()
+					continue
+				}
+
+				newEntry := &udpConnEntry{
+					link:   link,
+					cancel: cancel,
+				}
+				sessionPolicy := i.policyManager.ForLevel(uint32(i.user.Level))
+				newEntry.timer = signal.CancelAfterInactivity(sessCtx, func() {
+					udpConns.Delete(decoded.SessionID)
+					common.Interrupt(link.Reader)
+					common.Interrupt(link.Writer)
+					cancel()
+				}, sessionPolicy.Timeouts.ConnectionIdle)
+
+				actual, loaded := udpConns.LoadOrStore(decoded.SessionID, newEntry)
+				if loaded {
+					// Another goroutine/packet beat us to storing, terminate our redundant link
+					newEntry.timer.SetTimeout(0)
+					entry = actual
+				} else {
+					entry = newEntry
+					go func(sessID uint64, dest net.Destination, cEntry *udpConnEntry) {
+						defer func() {
+							cEntry.timer.SetTimeout(0)
+						}()
+						for {
+							resMb, err := cEntry.link.Reader.ReadMultiBuffer()
+							if err != nil {
+								return
+							}
+							cEntry.timer.Update()
+							for _, rb := range resMb {
+								encPacket, err := i.udpCodec.EncodeServerPacket(sessID, dest, rb.Bytes())
+								rb.Release()
+								if err != nil {
+									continue
+								}
+								_, _ = conn.Write(encPacket)
+							}
+						}
+					}(decoded.SessionID, decoded.Destination, entry)
 				}
 			}
+
+			entry.timer.Update()
+			payloadBuf := buf.New()
+			payloadBuf.Write(decoded.Payload)
+			b.Release()
+			_ = entry.link.Writer.WriteMultiBuffer(buf.MultiBuffer{payloadBuf})
 		}
 	}
 }
-
-func (i *Inbound) NewConnection(ctx context.Context, conn net.Conn, metadata M.Metadata) error {
-	inbound := session.InboundFromContext(ctx)
-	inbound.User = &protocol.MemoryUser{
-		Email: i.email,
-		Level: uint32(i.level),
-	}
-	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
-		From:   metadata.Source,
-		To:     metadata.Destination,
-		Status: log.AccessAccepted,
-		Email:  i.email,
-	})
-	errors.LogInfo(ctx, "tunnelling request to tcp:", metadata.Destination)
-	dispatcher := session.DispatcherFromContext(ctx)
-	destination, err := singbridge.ToDestination(metadata.Destination, net.Network_TCP)
-	if err != nil {
-		return err
-	}
-	link, err := dispatcher.Dispatch(ctx, destination)
-	if err != nil {
-		return err
-	}
-	return singbridge.CopyConn(ctx, nil, link, conn)
-}
-
-func (i *Inbound) NewPacketConnection(ctx context.Context, conn N.PacketConn, metadata M.Metadata) error {
-	inbound := session.InboundFromContext(ctx)
-	inbound.User = &protocol.MemoryUser{
-		Email: i.email,
-		Level: uint32(i.level),
-	}
-	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
-		From:   metadata.Source,
-		To:     metadata.Destination,
-		Status: log.AccessAccepted,
-		Email:  i.email,
-	})
-	errors.LogInfo(ctx, "tunnelling request to udp:", metadata.Destination)
-	dispatcher := session.DispatcherFromContext(ctx)
-	destination, err := singbridge.ToDestination(metadata.Destination, net.Network_UDP)
-	if err != nil {
-		return err
-	}
-	link, err := dispatcher.Dispatch(ctx, destination)
-	if err != nil {
-		return err
-	}
-	outConn := &singbridge.PacketConnWrapper{
-		Reader: link.Reader,
-		Writer: link.Writer,
-		Dest:   destination,
-		T: signal.CancelAfterInactivity(ctx, func() {
-			common.Interrupt(link.Reader)
-		}, 300*time.Second),
-	}
-	return bufio.CopyPacketConn(ctx, conn, outConn)
-}
-
-func (i *Inbound) NewError(ctx context.Context, err error) {
-	if E.IsClosed(err) {
-		return
-	}
-	errors.LogWarning(ctx, err.Error())
-}
-
-type natPacketConn struct {
-	net.Conn
-}
-
-func (c *natPacketConn) ReadPacket(buffer *B.Buffer) (addr M.Socksaddr, err error) {
-	_, err = buffer.ReadFrom(c)
-	return
-}
-
-func (c *natPacketConn) WritePacket(buffer *B.Buffer, addr M.Socksaddr) error {
-	_, err := buffer.WriteTo(c)
-	return err
-}

proxy/shadowsocks_2022/inbound_multi.go

@@ -2,21 +2,17 @@ package shadowsocks_2022
 
 import (
 	"context"
-	"encoding/base64"
+	"crypto/cipher"
+	"encoding/binary"
+	"io"
 	"strconv"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
-	"github.com/sagernet/sing-shadowsocks/shadowaead_2022"
-	C "github.com/sagernet/sing/common"
-	A "github.com/sagernet/sing/common/auth"
-	B "github.com/sagernet/sing/common/buf"
-	"github.com/sagernet/sing/common/bufio"
-	E "github.com/sagernet/sing/common/exceptions"
-	M "github.com/sagernet/sing/common/metadata"
-	N "github.com/sagernet/sing/common/network"
 	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/antireplay"
 	"github.com/xtls/xray-core/common/buf"
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/log"
@@ -24,8 +20,11 @@ import (
 	"github.com/xtls/xray-core/common/protocol"
 	"github.com/xtls/xray-core/common/session"
 	"github.com/xtls/xray-core/common/signal"
-	"github.com/xtls/xray-core/common/singbridge"
+	"github.com/xtls/xray-core/common/task"
+	"github.com/xtls/xray-core/common/utils"
 	"github.com/xtls/xray-core/common/uuid"
+	"github.com/xtls/xray-core/core"
+	"github.com/xtls/xray-core/features/policy"
 	"github.com/xtls/xray-core/features/routing"
 	"github.com/xtls/xray-core/transport/internet/stat"
 )
@@ -38,9 +37,16 @@ func init() {
 
 type MultiUserInbound struct {
 	sync.Mutex
-	networks []net.Network
-	users    []*protocol.MemoryUser
-	service  *shadowaead_2022.MultiService[int]
+	networks        []net.Network
+	method          *CipherMethod
+	masterPSK       []byte
+	usersByHash     *utils.TypedSyncMap[[AESBlockSize]byte, *protocol.MemoryUser]
+	usersByEmail    *utils.TypedSyncMap[string, *protocol.MemoryUser]
+	userCount       atomic.Int64
+	saltFilter      *antireplay.ReplayFilter[[32]byte]
+	udpSessions     *UDPSessionManager
+	udpMasterCipher cipher.Block
+	policyManager   policy.Manager
 }
 
 func NewMultiServer(ctx context.Context, config *MultiUserServerConfig) (*MultiUserInbound, error) {
@@ -51,138 +57,131 @@ func NewMultiServer(ctx context.Context, config *MultiUserServerConfig) (*MultiU
 			net.Network_UDP,
 		}
 	}
-	memUsers := []*protocol.MemoryUser{}
-	for i, user := range config.Users {
+
+	method, err := GetCipherMethod(config.Method)
+	if err != nil {
+		return nil, err
+	}
+	if method.IsChaCha {
+		return nil, errors.New("shadowsocks 2022 multi-user: only aes methods are supported")
+	}
+
+	masterPSK, err := ParseKey(config.Key, method.KeySaltLength)
+	if err != nil {
+		return nil, err
+	}
+
+	masterBlock, err := method.NewBlock(masterPSK)
+	if err != nil {
+		return nil, err
+	}
+
+	v := core.MustFromContext(ctx)
+	i := &MultiUserInbound{
+		networks:        networks,
+		method:          method,
+		masterPSK:       masterPSK,
+		usersByHash:     utils.NewTypedSyncMap[[AESBlockSize]byte, *protocol.MemoryUser](),
+		usersByEmail:    utils.NewTypedSyncMap[string, *protocol.MemoryUser](),
+		saltFilter:      antireplay.NewMapFilter[[32]byte](60),
+		udpSessions:     NewUDPSessionManager(500 * time.Second),
+		udpMasterCipher: masterBlock,
+		policyManager:   v.GetFeature(policy.ManagerType()).(policy.Manager),
+	}
+
+	for idx, user := range config.Users {
 		if user.Email == "" {
 			u := uuid.New()
-			user.Email = "unnamed-user-" + strconv.Itoa(i) + "-" + u.String()
+			user.Email = "unnamed-user-" + strconv.Itoa(idx) + "-" + u.String()
 		}
-		u, err := user.ToMemoryUser()
+		memUser, err := user.ToMemoryUser()
 		if err != nil {
-			return nil, errors.New("failed to get shadowsocks user").Base(err).AtError()
+			return nil, errors.New("failed to parse shadowsocks user").Base(err)
+		}
+		if err := i.AddUser(ctx, memUser); err != nil {
+			return nil, err
 		}
-		memUsers = append(memUsers, u)
 	}
 
-	inbound := &MultiUserInbound{
-		networks: networks,
-		users:    memUsers,
-	}
-	if config.Key == "" {
-		return nil, errors.New("missing key")
-	}
-	psk, err := base64.StdEncoding.DecodeString(config.Key)
-	if err != nil {
-		return nil, errors.New("parse config").Base(err)
-	}
-	service, err := shadowaead_2022.NewMultiService[int](config.Method, psk, 500, inbound, nil)
-	if err != nil {
-		return nil, errors.New("create service").Base(err)
-	}
-	err = service.UpdateUsersWithPasswords(
-		C.MapIndexed(memUsers, func(index int, it *protocol.MemoryUser) int { return index }),
-		C.Map(memUsers, func(it *protocol.MemoryUser) string { return it.Account.(*MemoryAccount).Key }),
-	)
-	if err != nil {
-		return nil, errors.New("create service").Base(err)
-	}
-
-	inbound.service = service
-	return inbound, nil
+	return i, nil
 }
 
-// AddUser implements proxy.UserManager.AddUser().
+// AddUser implements proxy.UserManager.AddUser()
 func (i *MultiUserInbound) AddUser(ctx context.Context, u *protocol.MemoryUser) error {
 	i.Lock()
 	defer i.Unlock()
 
+	var emailKey string
 	if u.Email != "" {
-		for idx := range i.users {
-			if i.users[idx].Email == u.Email {
-				return errors.New("User ", u.Email, " already exists.")
-			}
+		emailKey = strings.ToLower(u.Email)
+		if _, exists := i.usersByEmail.Load(emailKey); exists {
+			return errors.New("user ", u.Email, " already exists")
 		}
 	}
-	i.users = append(i.users, u)
 
-	// sync to multi service
-	// Considering implements shadowsocks2022 in xray-core may have better performance.
-	i.service.UpdateUsersWithPasswords(
-		C.MapIndexed(i.users, func(index int, it *protocol.MemoryUser) int { return index }),
-		C.Map(i.users, func(it *protocol.MemoryUser) string { return it.Account.(*MemoryAccount).Key }),
-	)
+	memAcc, ok := u.Account.(*MemoryAccount)
+	if !ok {
+		return errors.New("missing or invalid user account")
+	}
+
+	if len(memAcc.Key) != i.method.KeySaltLength {
+		return ErrBadKey
+	}
+
+	pskHash := DeriveUserPSKHash(memAcc.Key)
+	i.usersByHash.Store(pskHash, u)
+	if emailKey != "" {
+		i.usersByEmail.Store(emailKey, u)
+	}
+	i.userCount.Add(1)
 
 	return nil
 }
 
-// RemoveUser implements proxy.UserManager.RemoveUser().
+// RemoveUser implements proxy.UserManager.RemoveUser()
 func (i *MultiUserInbound) RemoveUser(ctx context.Context, email string) error {
 	if email == "" {
-		return errors.New("Email must not be empty.")
+		return errors.New("email must not be empty")
 	}
 
 	i.Lock()
 	defer i.Unlock()
 
-	idx := -1
-	for ii, u := range i.users {
-		if strings.EqualFold(u.Email, email) {
-			idx = ii
-			break
-		}
+	emailKey := strings.ToLower(email)
+	u, loaded := i.usersByEmail.LoadAndDelete(emailKey)
+	if !loaded {
+		return errors.New("user ", email, " not found")
 	}
 
-	if idx == -1 {
-		return errors.New("User ", email, " not found.")
-	}
-
-	ulen := len(i.users)
-
-	i.users[idx] = i.users[ulen-1]
-	i.users[ulen-1] = nil
-	i.users = i.users[:ulen-1]
-
-	// sync to multi service
-	// Considering implements shadowsocks2022 in xray-core may have better performance.
-	i.service.UpdateUsersWithPasswords(
-		C.MapIndexed(i.users, func(index int, it *protocol.MemoryUser) int { return index }),
-		C.Map(i.users, func(it *protocol.MemoryUser) string { return it.Account.(*MemoryAccount).Key }),
-	)
+	pskHash := DeriveUserPSKHash(u.Account.(*MemoryAccount).Key)
+	i.usersByHash.Delete(pskHash)
+	i.userCount.Add(-1)
 
 	return nil
 }
 
-// GetUser implements proxy.UserManager.GetUser().
+// GetUser implements proxy.UserManager.GetUser()
 func (i *MultiUserInbound) GetUser(ctx context.Context, email string) *protocol.MemoryUser {
 	if email == "" {
 		return nil
 	}
-
-	i.Lock()
-	defer i.Unlock()
-
-	for _, u := range i.users {
-		if strings.EqualFold(u.Email, email) {
-			return u
-		}
-	}
-	return nil
+	u, _ := i.usersByEmail.Load(strings.ToLower(email))
+	return u
 }
 
-// GetUsers implements proxy.UserManager.GetUsers().
+// GetUsers implements proxy.UserManager.GetUsers()
 func (i *MultiUserInbound) GetUsers(ctx context.Context) []*protocol.MemoryUser {
-	i.Lock()
-	defer i.Unlock()
-	dst := make([]*protocol.MemoryUser, len(i.users))
-	copy(dst, i.users)
-	return dst
+	var users []*protocol.MemoryUser
+	i.usersByEmail.Range(func(_ string, user *protocol.MemoryUser) bool {
+		users = append(users, user)
+		return true
+	})
+	return users
 }
 
-// GetUsersCount implements proxy.UserManager.GetUsersCount().
+// GetUsersCount implements proxy.UserManager.GetUsersCount()
 func (i *MultiUserInbound) GetUsersCount(context.Context) int64 {
-	i.Lock()
-	defer i.Unlock()
-	return int64(len(i.users))
+	return i.userCount.Load()
 }
 
 func (i *MultiUserInbound) Network() []net.Network {
@@ -194,97 +193,317 @@ func (i *MultiUserInbound) Process(ctx context.Context, network net.Network, con
 	inbound.Name = "shadowsocks-2022-multi"
 	inbound.CanSpliceCopy = 3
 
-	var metadata M.Metadata
-	if inbound.Source.IsValid() {
-		metadata.Source = M.ParseSocksaddr(inbound.Source.NetAddr())
+	if network == net.Network_TCP {
+		return i.processTCP(ctx, connection, dispatcher)
+	}
+	return i.processUDP(ctx, connection, dispatcher)
+}
+
+func (i *MultiUserInbound) processTCP(ctx context.Context, conn net.Conn, dispatcher routing.Dispatcher) error {
+	defer conn.Close()
+
+	sessionPolicy := i.policyManager.ForLevel(0)
+	if err := conn.SetReadDeadline(time.Now().Add(sessionPolicy.Timeouts.Handshake)); err != nil {
+		return errors.New("unable to set read deadline").Base(err)
 	}
 
-	ctx = session.ContextWithDispatcher(ctx, dispatcher)
+	// 1. Read Request Salt (16 or 32 bytes)
+	var salt [32]byte
+	saltSlice := salt[:i.method.KeySaltLength]
+	if _, err := io.ReadFull(conn, saltSlice); err != nil {
+		return err
+	}
 
-	if network == net.Network_TCP {
-		return singbridge.ReturnError(i.service.NewConnection(ctx, connection, metadata))
-	} else {
-		reader := buf.NewReader(connection)
-		pc := &natPacketConn{connection}
-		for {
-			mb, err := reader.ReadMultiBuffer()
-			if err != nil {
-				buf.ReleaseMulti(mb)
-				return singbridge.ReturnError(err)
+	if !i.saltFilter.Check(salt) {
+		return ErrSaltNotUnique
+	}
+
+	// 2. Read Extended Identity Header (16 bytes)
+	var eih [AESBlockSize]byte
+	if _, err := io.ReadFull(conn, eih[:]); err != nil {
+		return err
+	}
+
+	// Decrypt EIH with IdentitySubKey derived from masterPSK and salt
+	identitySubkey := DeriveIdentitySubKey(i.masterPSK, saltSlice, i.method.KeySaltLength)
+	block, err := i.method.NewBlock(identitySubkey)
+	if err != nil {
+		return err
+	}
+
+	var decryptedHash [AESBlockSize]byte
+	block.Decrypt(decryptedHash[:], eih[:])
+
+	// Lookup user
+	user, ok := i.usersByHash.Load(decryptedHash)
+	if !ok || user == nil {
+		return ErrInvalidRequest
+	}
+	userPSK := user.Account.(*MemoryAccount).Key
+
+	// 3. Derive Session Subkey using matched user's PSK
+	sessionKey := DeriveSessionSubKey(userPSK, saltSlice, i.method.KeySaltLength)
+	aead, err := i.method.NewAEAD(sessionKey)
+	if err != nil {
+		return err
+	}
+
+	reader := NewStreamReader(conn, aead)
+
+	// 4 & 5. Read Client Request Header
+	reqHeader, err := ReadClientRequestHeader(conn, reader)
+	if err != nil {
+		return err
+	}
+	conn.SetReadDeadline(time.Time{})
+	dest := reqHeader.Destination
+
+	// 6. Send Server Response Handshake
+	writer, err := WriteTCPResponse(conn, i.method, userPSK, saltSlice, nil)
+	if err != nil {
+		return err
+	}
+
+	// 7. Dispatch Connection to Xray routing with matched User
+	inbound := session.InboundFromContext(ctx)
+	inbound.User = user
+
+	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
+		From:   conn.RemoteAddr(),
+		To:     dest,
+		Status: log.AccessAccepted,
+		Email:  user.Email,
+	})
+
+	errors.LogInfo(ctx, "tunneling request to ", dest, " for user ", user.Email)
+
+	link, err := dispatcher.Dispatch(ctx, dest)
+	if err != nil {
+		return err
+	}
+
+	if len(reqHeader.EarlyData) > 0 {
+		earlyBuf := buf.New()
+		earlyBuf.Write(reqHeader.EarlyData)
+		if err := link.Writer.WriteMultiBuffer(buf.MultiBuffer{earlyBuf}); err != nil {
+			return err
+		}
+	}
+
+	sessionPolicy = i.policyManager.ForLevel(user.Level)
+	ctx, cancel := context.WithCancel(ctx)
+	timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle)
+	ctx = policy.ContextWithBufferPolicy(ctx, sessionPolicy.Buffer)
+
+	requestDone := func() error {
+		defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
+		return buf.Copy(reader, link.Writer, buf.UpdateActivity(timer))
+	}
+
+	responseDone := func() error {
+		defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
+		return buf.Copy(link.Reader, writer, buf.UpdateActivity(timer))
+	}
+
+	responseDoneAndCloseWriter := task.OnSuccess(responseDone, task.Close(link.Writer))
+	return task.Run(ctx, requestDone, responseDoneAndCloseWriter)
+}
+
+func (i *MultiUserInbound) processUDP(ctx context.Context, conn stat.Connection, dispatcher routing.Dispatcher) error {
+	udpConns := utils.NewTypedSyncMap[uint64, *udpConnEntry]()
+	defer func() {
+		udpConns.Range(func(key uint64, entry *udpConnEntry) bool {
+			entry.timer.SetTimeout(0)
+			return true
+		})
+	}()
+
+	reader := buf.NewReader(conn)
+	for {
+		mb, err := reader.ReadMultiBuffer()
+		if err != nil {
+			buf.ReleaseMulti(mb)
+			return err
+		}
+
+		for _, b := range mb {
+			// In multi-user UDP:
+			// Packet header is 16 bytes: Encrypted(SessionID + PacketID)
+			// Followed by 16 bytes EIH
+			packetBytes := b.Bytes()
+			if len(packetBytes) < 32+1+8+2 {
+				b.Release()
+				continue
 			}
-			for _, buffer := range mb {
-				packet := B.As(buffer.Bytes()).ToOwned()
-				buffer.Release()
-				err = i.service.NewPacket(ctx, pc, packet, metadata)
+
+			var rawHeader [16]byte
+			i.udpMasterCipher.Decrypt(rawHeader[:], packetBytes[:16])
+
+			sessionID := binary.BigEndian.Uint64(rawHeader[:8])
+			packetID := binary.BigEndian.Uint64(rawHeader[8:16])
+
+			// Replay protection & session lookup
+			sessionItem := i.udpSessions.GetOrCreate(sessionID)
+
+			sessionItem.Lock()
+			if !sessionItem.Window.Check(packetID) {
+				sessionItem.Unlock()
+				b.Release()
+				continue
+			}
+
+			var userPSK []byte
+			var currentUser *protocol.MemoryUser
+			if sessionItem.User != nil {
+				currentUser = sessionItem.User
+				userPSK = sessionItem.UserPSK
+				sessionItem.Unlock()
+			} else {
+				sessionItem.Unlock()
+				// Decrypt EIH
+				identitySubkey := DeriveIdentitySubKey(i.masterPSK, rawHeader[:8], i.method.KeySaltLength)
+				idBlock, err := i.method.NewBlock(identitySubkey)
 				if err != nil {
-					packet.Release()
-					buf.ReleaseMulti(mb)
-					return err
+					b.Release()
+					continue
+				}
+
+				var decryptedHash [16]byte
+				idBlock.Decrypt(decryptedHash[:], packetBytes[16:32])
+
+				user, ok := i.usersByHash.Load(decryptedHash)
+				if !ok || user == nil {
+					b.Release()
+					continue
+				}
+				currentUser = user
+				userPSK = user.Account.(*MemoryAccount).Key
+
+				sessionItem.Lock()
+				sessionItem.User = user
+				sessionItem.UserPSK = userPSK
+				sessionItem.Unlock()
+			}
+
+			// Decrypt Body (with AEAD caching per session)
+			bodyAead := sessionItem.GetRemoteCipher()
+			if bodyAead == nil {
+				bodyKey := DeriveSessionSubKey(userPSK, rawHeader[:8], i.method.KeySaltLength)
+				var err error
+				bodyAead, err = i.method.NewAEAD(bodyKey)
+				if err != nil {
+					b.Release()
+					continue
+				}
+				sessionItem.SetRemoteCipher(bodyAead)
+			}
+
+			bodyNonce := rawHeader[4:16]
+			bodyCipher := packetBytes[32:]
+			bodyPlain, err := bodyAead.Open(nil, bodyNonce, bodyCipher, nil)
+			b.Release()
+			if err != nil || len(bodyPlain) < 1+8+2 {
+				continue
+			}
+
+			sessionItem.Lock()
+			sessionItem.Window.Add(packetID)
+			sessionItem.Unlock()
+
+			if bodyPlain[0] != HeaderTypeClient {
+				continue
+			}
+			epoch := binary.BigEndian.Uint64(bodyPlain[1:9])
+			diff := time.Now().Unix() - int64(epoch)
+			if diff < -30 || diff > 30 {
+				continue
+			}
+
+			paddingLen := int(binary.BigEndian.Uint16(bodyPlain[9:11]))
+			offset := 11 + paddingLen
+			if len(bodyPlain) < offset {
+				continue
+			}
+
+			dest, addrLen, err := parseAddressPort(bodyPlain[offset:])
+			if err != nil {
+				continue
+			}
+
+			payload := bodyPlain[offset+addrLen:]
+
+			entry, ok := udpConns.Load(sessionID)
+			if !ok {
+				sessCtx, cancel := context.WithCancel(ctx)
+				inbound := session.InboundFromContext(sessCtx)
+				inbound.User = currentUser
+
+				sessCtx = log.ContextWithAccessMessage(sessCtx, &log.AccessMessage{
+					From:   conn.RemoteAddr(),
+					To:     dest,
+					Status: log.AccessAccepted,
+					Email:  currentUser.Email,
+				})
+
+				link, err := dispatcher.Dispatch(sessCtx, dest)
+				if err != nil {
+					cancel()
+					continue
+				}
+
+				newEntry := &udpConnEntry{
+					link:   link,
+					cancel: cancel,
+				}
+				sessionPolicy := i.policyManager.ForLevel(currentUser.Level)
+				newEntry.timer = signal.CancelAfterInactivity(sessCtx, func() {
+					udpConns.Delete(sessionID)
+					common.Interrupt(link.Reader)
+					common.Interrupt(link.Writer)
+					cancel()
+				}, sessionPolicy.Timeouts.ConnectionIdle)
+
+				actual, loaded := udpConns.LoadOrStore(sessionID, newEntry)
+				if loaded {
+					newEntry.timer.SetTimeout(0)
+					entry = actual
+				} else {
+					entry = newEntry
+					go func(sessID uint64, uPSK []byte, d net.Destination, cEntry *udpConnEntry) {
+						defer func() {
+							cEntry.timer.SetTimeout(0)
+						}()
+						for {
+							resMb, err := cEntry.link.Reader.ReadMultiBuffer()
+							if err != nil {
+								return
+							}
+							cEntry.timer.Update()
+							for _, rb := range resMb {
+								encPacket, err := i.encodeServerUDPPacket(sessID, uPSK, d, rb.Bytes())
+								rb.Release()
+								if err != nil {
+									continue
+								}
+								_, _ = conn.Write(encPacket)
+							}
+						}
+					}(sessionID, userPSK, dest, entry)
 				}
 			}
+
+			entry.timer.Update()
+			pBuf := buf.New()
+			pBuf.Write(payload)
+			_ = entry.link.Writer.WriteMultiBuffer(buf.MultiBuffer{pBuf})
 		}
 	}
 }
 
-func (i *MultiUserInbound) NewConnection(ctx context.Context, conn net.Conn, metadata M.Metadata) error {
-	inbound := session.InboundFromContext(ctx)
-	userInt, _ := A.UserFromContext[int](ctx)
-	user := i.users[userInt]
-	inbound.User = user
-	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
-		From:   metadata.Source,
-		To:     metadata.Destination,
-		Status: log.AccessAccepted,
-		Email:  user.Email,
-	})
-	errors.LogInfo(ctx, "tunnelling request to tcp:", metadata.Destination)
-	dispatcher := session.DispatcherFromContext(ctx)
-	destination, err := singbridge.ToDestination(metadata.Destination, net.Network_TCP)
-	if err != nil {
-		return err
+func (i *MultiUserInbound) encodeServerUDPPacket(clientSessionID uint64, userPSK []byte, dest net.Destination, payload []byte) ([]byte, error) {
+	sessionItem := i.udpSessions.GetOrCreate(clientSessionID)
+	if err := sessionItem.EnsureServerState(i.method, i.udpMasterCipher, nil, userPSK); err != nil {
+		return nil, err
 	}
-	link, err := dispatcher.Dispatch(ctx, destination)
-	if err != nil {
-		return err
-	}
-	return singbridge.CopyConn(ctx, conn, link, conn)
-}
-
-func (i *MultiUserInbound) NewPacketConnection(ctx context.Context, conn N.PacketConn, metadata M.Metadata) error {
-	inbound := session.InboundFromContext(ctx)
-	userInt, _ := A.UserFromContext[int](ctx)
-	user := i.users[userInt]
-	inbound.User = user
-	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
-		From:   metadata.Source,
-		To:     metadata.Destination,
-		Status: log.AccessAccepted,
-		Email:  user.Email,
-	})
-	errors.LogInfo(ctx, "tunnelling request to udp:", metadata.Destination)
-	dispatcher := session.DispatcherFromContext(ctx)
-	destination, err := singbridge.ToDestination(metadata.Destination, net.Network_UDP)
-	if err != nil {
-		return err
-	}
-	link, err := dispatcher.Dispatch(ctx, destination)
-	if err != nil {
-		return err
-	}
-	outConn := &singbridge.PacketConnWrapper{
-		Reader: link.Reader,
-		Writer: link.Writer,
-		Dest:   destination,
-		T: signal.CancelAfterInactivity(ctx, func() {
-			common.Interrupt(link.Reader)
-		}, 300*time.Second),
-	}
-	return bufio.CopyPacketConn(ctx, conn, outConn)
-}
-
-func (i *MultiUserInbound) NewError(ctx context.Context, err error) {
-	if E.IsClosed(err) {
-		return
-	}
-	errors.LogWarning(ctx, err.Error())
+	return sessionItem.EncodeServerPacket(i.method, clientSessionID, dest, payload)
 }

proxy/shadowsocks_2022/inbound_relay.go

@@ -2,18 +2,12 @@ package shadowsocks_2022
 
 import (
 	"context"
+	"crypto/cipher"
+	"encoding/binary"
+	"io"
 	"strconv"
-	"strings"
 	"time"
 
-	"github.com/sagernet/sing-shadowsocks/shadowaead_2022"
-	C "github.com/sagernet/sing/common"
-	A "github.com/sagernet/sing/common/auth"
-	B "github.com/sagernet/sing/common/buf"
-	"github.com/sagernet/sing/common/bufio"
-	E "github.com/sagernet/sing/common/exceptions"
-	M "github.com/sagernet/sing/common/metadata"
-	N "github.com/sagernet/sing/common/network"
 	"github.com/xtls/xray-core/common"
 	"github.com/xtls/xray-core/common/buf"
 	"github.com/xtls/xray-core/common/errors"
@@ -22,8 +16,11 @@ import (
 	"github.com/xtls/xray-core/common/protocol"
 	"github.com/xtls/xray-core/common/session"
 	"github.com/xtls/xray-core/common/signal"
-	"github.com/xtls/xray-core/common/singbridge"
+	"github.com/xtls/xray-core/common/task"
+	"github.com/xtls/xray-core/common/utils"
 	"github.com/xtls/xray-core/common/uuid"
+	"github.com/xtls/xray-core/core"
+	"github.com/xtls/xray-core/features/policy"
 	"github.com/xtls/xray-core/features/routing"
 	"github.com/xtls/xray-core/transport/internet/stat"
 )
@@ -34,10 +31,22 @@ func init() {
 	}))
 }
 
+type relayDest struct {
+	destination net.Destination
+	email       string
+	level       uint32
+	key         []byte
+	blockCipher cipher.Block
+}
+
 type RelayInbound struct {
-	networks     []net.Network
-	destinations []*RelayDestination
-	service      *shadowaead_2022.RelayService[int]
+	networks        []net.Network
+	method          *CipherMethod
+	relayPSK        []byte
+	relayBlock      cipher.Block
+	destinations    map[[AESBlockSize]byte]*relayDest
+	rawDestinations []*RelayDestination
+	policyManager   policy.Manager
 }
 
 func NewRelayServer(ctx context.Context, config *RelayServerConfig) (*RelayInbound, error) {
@@ -48,39 +57,63 @@ func NewRelayServer(ctx context.Context, config *RelayServerConfig) (*RelayInbou
 			net.Network_UDP,
 		}
 	}
-	inbound := &RelayInbound{
-		networks:     networks,
-		destinations: config.Destinations,
-	}
-	if !C.Contains(shadowaead_2022.List, config.Method) || !strings.Contains(config.Method, "aes") {
-		return nil, errors.New("unsupported method ", config.Method)
-	}
-	service, err := shadowaead_2022.NewRelayServiceWithPassword[int](config.Method, config.Key, 500, inbound)
+
+	method, err := GetCipherMethod(config.Method)
 	if err != nil {
-		return nil, errors.New("create service").Base(err)
+		return nil, err
+	}
+	if method.IsChaCha {
+		return nil, errors.New("shadowsocks 2022 relay: only aes methods are supported")
 	}
 
-	for i, destination := range config.Destinations {
-		if destination.Email == "" {
+	relayPSK, err := ParseKey(config.Key, method.KeySaltLength)
+	if err != nil {
+		return nil, err
+	}
+
+	relayBlock, err := method.NewBlock(relayPSK)
+	if err != nil {
+		return nil, err
+	}
+
+	v := core.MustFromContext(ctx)
+	i := &RelayInbound{
+		networks:        networks,
+		method:          method,
+		relayPSK:        relayPSK,
+		relayBlock:      relayBlock,
+		destinations:    make(map[[AESBlockSize]byte]*relayDest),
+		rawDestinations: config.Destinations,
+		policyManager:   v.GetFeature(policy.ManagerType()).(policy.Manager),
+	}
+
+	for idx, d := range config.Destinations {
+		if d.Email == "" {
 			u := uuid.New()
-			destination.Email = "unnamed-destination-" + strconv.Itoa(i) + "-" + u.String()
+			d.Email = "unnamed-destination-" + strconv.Itoa(idx) + "-" + u.String()
+		}
+		destKey, err := ParseKey(d.Key, method.KeySaltLength)
+		if err != nil {
+			return nil, err
+		}
+
+		destBlock, err := method.NewBlock(destKey)
+		if err != nil {
+			return nil, err
+		}
+
+		hash := DeriveUserPSKHash(destKey)
+
+		i.destinations[hash] = &relayDest{
+			destination: net.TCPDestination(d.Address.AsAddress(), net.Port(d.Port)),
+			email:       d.Email,
+			level:       uint32(d.Level),
+			key:         destKey,
+			blockCipher: destBlock,
 		}
 	}
-	err = service.UpdateUsersWithPasswords(
-		C.MapIndexed(config.Destinations, func(index int, it *RelayDestination) int { return index }),
-		C.Map(config.Destinations, func(it *RelayDestination) string { return it.Key }),
-		C.Map(config.Destinations, func(it *RelayDestination) M.Socksaddr {
-			return singbridge.ToSocksaddr(net.Destination{
-				Address: it.Address.AsAddress(),
-				Port:    net.Port(it.Port),
-			})
-		}),
-	)
-	if err != nil {
-		return nil, errors.New("create service").Base(err)
-	}
-	inbound.service = service
-	return inbound, nil
+
+	return i, nil
 }
 
 func (i *RelayInbound) Network() []net.Network {
@@ -92,103 +125,206 @@ func (i *RelayInbound) Process(ctx context.Context, network net.Network, connect
 	inbound.Name = "shadowsocks-2022-relay"
 	inbound.CanSpliceCopy = 3
 
-	var metadata M.Metadata
-	if inbound.Source.IsValid() {
-		metadata.Source = M.ParseSocksaddr(inbound.Source.NetAddr())
+	if network == net.Network_TCP {
+		return i.processTCP(ctx, connection, dispatcher)
+	}
+	return i.processUDP(ctx, connection, dispatcher)
+}
+
+func (i *RelayInbound) processTCP(ctx context.Context, conn net.Conn, dispatcher routing.Dispatcher) error {
+	defer conn.Close()
+
+	sessionPolicy := i.policyManager.ForLevel(0)
+	if err := conn.SetReadDeadline(time.Now().Add(sessionPolicy.Timeouts.Handshake)); err != nil {
+		return errors.New("unable to set read deadline").Base(err)
 	}
 
-	ctx = session.ContextWithDispatcher(ctx, dispatcher)
+	// Read Salt + Outer EIH
+	needed := i.method.KeySaltLength + AESBlockSize
+	var headerBuf [48]byte
+	headerSlice := headerBuf[:needed]
+	if _, err := io.ReadFull(conn, headerSlice); err != nil {
+		return err
+	}
 
-	if network == net.Network_TCP {
-		return singbridge.ReturnError(i.service.NewConnection(ctx, connection, metadata))
-	} else {
-		reader := buf.NewReader(connection)
-		pc := &natPacketConn{connection}
-		for {
-			mb, err := reader.ReadMultiBuffer()
-			if err != nil {
-				buf.ReleaseMulti(mb)
-				return singbridge.ReturnError(err)
+	salt := headerSlice[:i.method.KeySaltLength]
+	eih := headerSlice[i.method.KeySaltLength:]
+
+	identitySubkey := DeriveIdentitySubKey(i.relayPSK, salt, i.method.KeySaltLength)
+	block, err := i.method.NewBlock(identitySubkey)
+	if err != nil {
+		return err
+	}
+
+	var decryptedHash [AESBlockSize]byte
+	block.Decrypt(decryptedHash[:], eih)
+
+	targetDest, ok := i.destinations[decryptedHash]
+	if !ok {
+		return ErrInvalidRequest
+	}
+	conn.SetReadDeadline(time.Time{})
+
+	inbound := session.InboundFromContext(ctx)
+	inbound.User = &protocol.MemoryUser{
+		Email: targetDest.email,
+		Level: targetDest.level,
+	}
+
+	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
+		From:   conn.RemoteAddr(),
+		To:     targetDest.destination,
+		Status: log.AccessAccepted,
+		Email:  targetDest.email,
+	})
+
+	errors.LogInfo(ctx, "relaying connection to ", targetDest.destination)
+
+	link, err := dispatcher.Dispatch(ctx, targetDest.destination)
+	if err != nil {
+		return err
+	}
+
+	// Unwrap outer EIH: send client salt to next hop, stripping this hop's EIH
+	saltBuf := buf.New()
+	saltBuf.Write(salt)
+	if err := link.Writer.WriteMultiBuffer(buf.MultiBuffer{saltBuf}); err != nil {
+		return err
+	}
+
+	sessionPolicy = i.policyManager.ForLevel(targetDest.level)
+	ctx, cancel := context.WithCancel(ctx)
+	timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle)
+	ctx = policy.ContextWithBufferPolicy(ctx, sessionPolicy.Buffer)
+
+	requestDone := func() error {
+		defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
+		return buf.Copy(buf.NewReader(conn), link.Writer, buf.UpdateActivity(timer))
+	}
+
+	responseDone := func() error {
+		defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
+		return buf.Copy(link.Reader, buf.NewWriter(conn), buf.UpdateActivity(timer))
+	}
+
+	responseDoneAndCloseWriter := task.OnSuccess(responseDone, task.Close(link.Writer))
+	return task.Run(ctx, requestDone, responseDoneAndCloseWriter)
+}
+
+func (i *RelayInbound) processUDP(ctx context.Context, conn stat.Connection, dispatcher routing.Dispatcher) error {
+	udpConns := utils.NewTypedSyncMap[uint64, *udpConnEntry]()
+	defer func() {
+		udpConns.Range(func(key uint64, entry *udpConnEntry) bool {
+			entry.timer.SetTimeout(0)
+			return true
+		})
+	}()
+
+	reader := buf.NewReader(conn)
+	for {
+		mb, err := reader.ReadMultiBuffer()
+		if err != nil {
+			buf.ReleaseMulti(mb)
+			return err
+		}
+
+		for _, b := range mb {
+			data := b.Bytes()
+			if len(data) < 2*AESBlockSize {
+				b.Release()
+				continue
 			}
-			for _, buffer := range mb {
-				packet := B.As(buffer.Bytes()).ToOwned()
-				buffer.Release()
-				err = i.service.NewPacket(ctx, pc, packet, metadata)
+
+			var packetHeader [AESBlockSize]byte
+			i.relayBlock.Decrypt(packetHeader[:], data[:AESBlockSize])
+
+			var eiHeader [AESBlockSize]byte
+			i.relayBlock.Decrypt(eiHeader[:], data[AESBlockSize:2*AESBlockSize])
+			for idx := 0; idx < AESBlockSize; idx++ {
+				eiHeader[idx] ^= packetHeader[idx]
+			}
+
+			targetDest, ok := i.destinations[eiHeader]
+			if !ok {
+				b.Release()
+				continue
+			}
+
+			// Extract sessionID from raw packetHeader for session-level link caching before re-encrypting
+			sessionID := binary.BigEndian.Uint64(packetHeader[:8])
+
+			// Re-encrypt packetHeader with next hop block cipher
+			targetDest.blockCipher.Encrypt(packetHeader[:], packetHeader[:])
+
+			// Strip outer EIH: replace second block with re-encrypted packetHeader and advance
+			copy(data[AESBlockSize:2*AESBlockSize], packetHeader[:])
+			b.Advance(int32(AESBlockSize))
+
+			dest := targetDest.destination
+			dest.Network = net.Network_UDP
+
+			entry, ok := udpConns.Load(sessionID)
+			if !ok {
+				sessCtx, cancel := context.WithCancel(ctx)
+				inbound := session.InboundFromContext(sessCtx)
+				inbound.User = &protocol.MemoryUser{
+					Email: targetDest.email,
+					Level: targetDest.level,
+				}
+
+				sessCtx = log.ContextWithAccessMessage(sessCtx, &log.AccessMessage{
+					From:   conn.RemoteAddr(),
+					To:     dest,
+					Status: log.AccessAccepted,
+					Email:  targetDest.email,
+				})
+
+				link, err := dispatcher.Dispatch(sessCtx, dest)
 				if err != nil {
-					packet.Release()
-					buf.ReleaseMulti(mb)
-					return err
+					cancel()
+					b.Release()
+					continue
+				}
+
+				newEntry := &udpConnEntry{
+					link:   link,
+					cancel: cancel,
+				}
+				sessionPolicy := i.policyManager.ForLevel(targetDest.level)
+				newEntry.timer = signal.CancelAfterInactivity(sessCtx, func() {
+					udpConns.Delete(sessionID)
+					common.Interrupt(link.Reader)
+					common.Interrupt(link.Writer)
+					cancel()
+				}, sessionPolicy.Timeouts.ConnectionIdle)
+
+				actual, loaded := udpConns.LoadOrStore(sessionID, newEntry)
+				if loaded {
+					newEntry.timer.SetTimeout(0)
+					entry = actual
+				} else {
+					entry = newEntry
+					go func(cEntry *udpConnEntry) {
+						defer func() {
+							cEntry.timer.SetTimeout(0)
+						}()
+						for {
+							resMb, err := cEntry.link.Reader.ReadMultiBuffer()
+							if err != nil {
+								return
+							}
+							cEntry.timer.Update()
+							for _, rb := range resMb {
+								_, _ = conn.Write(rb.Bytes())
+								rb.Release()
+							}
+						}
+					}(entry)
 				}
 			}
+
+			entry.timer.Update()
+			_ = entry.link.Writer.WriteMultiBuffer(buf.MultiBuffer{b})
 		}
 	}
 }
-
-func (i *RelayInbound) NewConnection(ctx context.Context, conn net.Conn, metadata M.Metadata) error {
-	inbound := session.InboundFromContext(ctx)
-	userInt, _ := A.UserFromContext[int](ctx)
-	user := i.destinations[userInt]
-	inbound.User = &protocol.MemoryUser{
-		Email: user.Email,
-		Level: uint32(user.Level),
-	}
-	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
-		From:   metadata.Source,
-		To:     metadata.Destination,
-		Status: log.AccessAccepted,
-		Email:  user.Email,
-	})
-	errors.LogInfo(ctx, "tunnelling request to tcp:", metadata.Destination)
-	dispatcher := session.DispatcherFromContext(ctx)
-	destination, err := singbridge.ToDestination(metadata.Destination, net.Network_TCP)
-	if err != nil {
-		return err
-	}
-	link, err := dispatcher.Dispatch(ctx, destination)
-	if err != nil {
-		return err
-	}
-	return singbridge.CopyConn(ctx, nil, link, conn)
-}
-
-func (i *RelayInbound) NewPacketConnection(ctx context.Context, conn N.PacketConn, metadata M.Metadata) error {
-	inbound := session.InboundFromContext(ctx)
-	userInt, _ := A.UserFromContext[int](ctx)
-	user := i.destinations[userInt]
-	inbound.User = &protocol.MemoryUser{
-		Email: user.Email,
-		Level: uint32(user.Level),
-	}
-	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
-		From:   metadata.Source,
-		To:     metadata.Destination,
-		Status: log.AccessAccepted,
-		Email:  user.Email,
-	})
-	errors.LogInfo(ctx, "tunnelling request to udp:", metadata.Destination)
-	dispatcher := session.DispatcherFromContext(ctx)
-	destination, err := singbridge.ToDestination(metadata.Destination, net.Network_UDP)
-	if err != nil {
-		return err
-	}
-	link, err := dispatcher.Dispatch(ctx, destination)
-	if err != nil {
-		return err
-	}
-	outConn := &singbridge.PacketConnWrapper{
-		Reader: link.Reader,
-		Writer: link.Writer,
-		Dest:   destination,
-		T: signal.CancelAfterInactivity(ctx, func() {
-			common.Interrupt(link.Reader)
-		}, 300*time.Second),
-	}
-	return bufio.CopyPacketConn(ctx, conn, outConn)
-}
-
-func (i *RelayInbound) NewError(ctx context.Context, err error) {
-	if E.IsClosed(err) {
-		return
-	}
-	errors.LogWarning(ctx, err.Error())
-}

proxy/shadowsocks_2022/kdf.go

@@ -0,0 +1,63 @@
+package shadowsocks_2022
+
+import (
+	"encoding/base64"
+	"strings"
+
+	"lukechampine.com/blake3"
+)
+
+const (
+	ContextSessionSubKey  = "shadowsocks 2022 session subkey"
+	ContextIdentitySubKey = "shadowsocks 2022 identity subkey"
+)
+
+// ParseKey decodes a base64 or raw PSK key string and validates its length
+func ParseKey(key string, keyLength int) ([]byte, error) {
+	raw, err := base64.StdEncoding.DecodeString(key)
+	if err != nil {
+		raw = []byte(key)
+	}
+	if len(raw) != keyLength {
+		return nil, ErrBadKey
+	}
+	return raw, nil
+}
+
+func ParsePSKList(password string, keyLength int) ([][]byte, error) {
+	parts := strings.Split(password, ":")
+	pskList := make([][]byte, len(parts))
+	for i, part := range parts {
+		norm, err := ParseKey(part, keyLength)
+		if err != nil {
+			return nil, err
+		}
+		pskList[i] = norm
+	}
+	return pskList, nil
+}
+
+func deriveSubKey(ctx string, psk, salt []byte, keyLength int) []byte {
+	var keyMaterial [64]byte
+	kmLen := len(psk) + len(salt)
+	copy(keyMaterial[:], psk)
+	copy(keyMaterial[len(psk):], salt)
+	out := make([]byte, keyLength)
+	blake3.DeriveKey(out, ctx, keyMaterial[:kmLen])
+	return out
+}
+
+func DeriveSessionSubKey(psk, salt []byte, keyLength int) []byte {
+	return deriveSubKey(ContextSessionSubKey, psk, salt, keyLength)
+}
+
+func DeriveIdentitySubKey(psk, salt []byte, keyLength int) []byte {
+	return deriveSubKey(ContextIdentitySubKey, psk, salt, keyLength)
+}
+
+func DeriveUserPSKHash(userPSK []byte) [AESBlockSize]byte {
+	h := blake3.Sum512(userPSK)
+	var out [AESBlockSize]byte
+	copy(out[:], h[:AESBlockSize])
+	return out
+}

proxy/shadowsocks_2022/outbound.go

@@ -2,21 +2,20 @@ package shadowsocks_2022
 
 import (
 	"context"
+	"crypto/rand"
+	"io"
 	"time"
 
-	shadowsocks "github.com/sagernet/sing-shadowsocks"
-	"github.com/sagernet/sing-shadowsocks/shadowaead_2022"
-	C "github.com/sagernet/sing/common"
-	B "github.com/sagernet/sing/common/buf"
-	"github.com/sagernet/sing/common/bufio"
-	N "github.com/sagernet/sing/common/network"
 	"github.com/xtls/xray-core/common"
 	"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/retry"
 	"github.com/xtls/xray-core/common/session"
 	"github.com/xtls/xray-core/common/signal"
-	"github.com/xtls/xray-core/common/singbridge"
+	"github.com/xtls/xray-core/common/task"
+	"github.com/xtls/xray-core/core"
+	"github.com/xtls/xray-core/features/policy"
 	"github.com/xtls/xray-core/transport"
 	"github.com/xtls/xray-core/transport/internet"
 )
@@ -28,42 +27,47 @@ func init() {
 }
 
 type Outbound struct {
-	ctx    context.Context
-	server net.Destination
-	method shadowsocks.Method
+	server        net.Destination
+	method        *CipherMethod
+	pskList       [][]byte
+	finalPSK      []byte
+	udpCodec      *UDPPacketCodec
+	policyManager policy.Manager
 }
 
 func NewClient(ctx context.Context, config *ClientConfig) (*Outbound, error) {
-	o := &Outbound{
-		ctx: ctx,
+	method, err := GetCipherMethod(config.Method)
+	if err != nil {
+		return nil, errors.New("unsupported method: ", config.Method).Base(err)
+	}
+
+	pskList, err := ParsePSKList(config.Key, method.KeySaltLength)
+	if err != nil {
+		return nil, errors.New("invalid key: ", config.Key).Base(err)
+	}
+
+	finalPSK := pskList[len(pskList)-1]
+	udpCodec, err := NewUDPPacketCodec(method, finalPSK)
+	if err != nil {
+		return nil, errors.New("failed to create udp packet codec").Base(err)
+	}
+
+	v := core.MustFromContext(ctx)
+	return &Outbound{
 		server: net.Destination{
 			Address: config.Address.AsAddress(),
 			Port:    net.Port(config.Port),
 			Network: net.Network_TCP,
 		},
-	}
-	if C.Contains(shadowaead_2022.List, config.Method) {
-		if config.Key == "" {
-			return nil, errors.New("missing psk")
-		}
-		method, err := shadowaead_2022.NewWithPassword(config.Method, config.Key, nil)
-		if err != nil {
-			return nil, errors.New("create method").Base(err)
-		}
-		o.method = method
-	} else {
-		return nil, errors.New("unknown method ", config.Method)
-	}
-	return o, nil
+		method:        method,
+		pskList:       pskList,
+		finalPSK:      finalPSK,
+		udpCodec:      udpCodec,
+		policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager),
+	}, nil
 }
 
 func (o *Outbound) Process(ctx context.Context, link *transport.Link, dialer internet.Dialer) error {
-	var inboundConn net.Conn
-	inbound := session.InboundFromContext(ctx)
-	if inbound != nil {
-		inboundConn = inbound.Conn
-	}
-
 	outbounds := session.OutboundsFromContext(ctx)
 	ob := outbounds[len(outbounds)-1]
 	if !ob.Target.IsValid() {
@@ -78,70 +82,123 @@ func (o *Outbound) Process(ctx context.Context, link *transport.Link, dialer int
 
 	serverDestination := o.server
 	serverDestination.Network = network
-	connection, err := dialer.Dial(ctx, serverDestination)
-	if err != nil {
-		return errors.New("failed to connect to server").Base(err)
-	}
-	defer connection.Close()
 
+	var conn net.Conn
+	if err := retry.ExponentialBackoff(5, 100).On(func() error {
+		rawConn, err := dialer.Dial(ctx, serverDestination)
+		if err != nil {
+			return err
+		}
+		conn = rawConn
+		return nil
+	}); err != nil {
+		return errors.New("failed to find an available destination").Base(err)
+	}
+	defer conn.Close()
+
+	var newCtx context.Context
+	var newCancel context.CancelFunc
 	if session.TimeoutOnlyFromContext(ctx) {
-		ctx, _ = context.WithCancel(context.Background())
+		newCtx, newCancel = context.WithCancel(context.Background())
+	}
+
+	sessionPolicy := o.policyManager.ForLevel(0)
+	ctx, cancel := context.WithCancel(ctx)
+	timer := signal.CancelAfterInactivity(ctx, func() {
+		cancel()
+		if newCancel != nil {
+			newCancel()
+		}
+	}, sessionPolicy.Timeouts.ConnectionIdle)
+
+	ctx = policy.ContextWithBufferPolicy(ctx, sessionPolicy.Buffer)
+
+	if newCtx != nil {
+		ctx = newCtx
 	}
 
 	if network == net.Network_TCP {
-		serverConn := o.method.DialEarlyConn(connection, singbridge.ToSocksaddr(destination))
-		var handshake bool
-		if timeoutReader, isTimeoutReader := link.Reader.(buf.TimeoutReader); isTimeoutReader {
-			mb, err := timeoutReader.ReadMultiBufferTimeout(time.Millisecond * 100)
-			if err != nil && err != buf.ErrNotTimeoutReader && err != buf.ErrReadTimeout {
-				return errors.New("read payload").Base(err)
-			}
-			payload := B.New()
-			for {
-				payload.Reset()
-				nb, n := buf.SplitBytes(mb, payload.FreeBytes())
-				if n > 0 {
-					payload.Truncate(n)
-					_, err = serverConn.Write(payload.Bytes())
-					if err != nil {
-						payload.Release()
-						return errors.New("write payload").Base(err)
-					}
-					handshake = true
-				}
-				if nb.IsEmpty() {
-					break
-				}
-				mb = nb
-			}
-			payload.Release()
-		}
-		if !handshake {
-			_, err = serverConn.Write(nil)
-			if err != nil {
-				return errors.New("client handshake").Base(err)
-			}
-		}
-		return singbridge.CopyConn(ctx, inboundConn, link, serverConn)
-	} else {
-		var packetConn N.PacketConn
-		if pc, isPacketConn := inboundConn.(N.PacketConn); isPacketConn {
-			packetConn = pc
-		} else if nc, isNetPacket := inboundConn.(net.PacketConn); isNetPacket {
-			packetConn = bufio.NewPacketConn(nc)
-		} else {
-			packetConn = &singbridge.PacketConnWrapper{
-				Reader: link.Reader,
-				Writer: link.Writer,
-				Conn:   inboundConn,
-				Dest:   destination,
-				T: signal.CancelAfterInactivity(ctx, func() {
-					common.Interrupt(link.Reader)
-				}, 300*time.Second),
-			}
+		var clientSalt [32]byte
+		clientSaltSlice := clientSalt[:o.method.KeySaltLength]
+		if _, err := io.ReadFull(rand.Reader, clientSaltSlice); err != nil {
+			return errors.New("failed to generate client salt").Base(err)
 		}
 
-		serverConn := o.method.DialPacketConn(connection)
-		return singbridge.ReturnError(bufio.CopyPacketConn(ctx, packetConn, serverConn))
+		requestDone := func() error {
+			defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
+			bufferedWriter := buf.NewBufferedWriter(buf.NewWriter(conn))
+			bodyWriter, err := WriteTCPRequest(bufferedWriter, o.method, o.pskList, destination, clientSaltSlice, nil)
+			if err != nil {
+				return errors.New("failed to write request").Base(err)
+			}
+
+			if err = buf.CopyOnceTimeout(link.Reader, bodyWriter, time.Millisecond*100); err != nil && err != buf.ErrNotTimeoutReader && err != buf.ErrReadTimeout {
+				return errors.New("failed to write A request payload").Base(err)
+			}
+
+			if err := bufferedWriter.SetBuffered(false); err != nil {
+				return err
+			}
+
+			return buf.Copy(link.Reader, bodyWriter, buf.UpdateActivity(timer))
+		}
+
+		responseDone := func() error {
+			defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
+
+			responseReader, err := ReadTCPResponse(conn, o.method, o.finalPSK, clientSaltSlice)
+			if err != nil {
+				return err
+			}
+
+			return buf.Copy(responseReader, link.Writer, buf.UpdateActivity(timer))
+		}
+
+		responseDoneAndCloseWriter := task.OnSuccess(responseDone, task.Close(link.Writer))
+		if err := task.Run(ctx, requestDone, responseDoneAndCloseWriter); err != nil {
+			return errors.New("connection ends").Base(err)
+		}
+
+		return nil
 	}
+
+	if network == net.Network_UDP {
+		requestDone := func() error {
+			defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
+
+			writer := &UDPWriter{
+				Writer:      conn,
+				Destination: destination,
+				Codec:       o.udpCodec,
+			}
+
+			if err := buf.Copy(link.Reader, writer, buf.UpdateActivity(timer)); err != nil {
+				return errors.New("failed to transport all UDP request").Base(err)
+			}
+			return nil
+		}
+
+		responseDone := func() error {
+			defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
+
+			reader := &UDPReader{
+				Reader: conn,
+				Codec:  o.udpCodec,
+			}
+
+			if err := buf.Copy(reader, link.Writer, buf.UpdateActivity(timer)); err != nil {
+				return errors.New("failed to transport all UDP response").Base(err)
+			}
+			return nil
+		}
+
+		responseDoneAndCloseWriter := task.OnSuccess(responseDone, task.Close(link.Writer))
+		if err := task.Run(ctx, requestDone, responseDoneAndCloseWriter); err != nil {
+			return errors.New("connection ends").Base(err)
+		}
+
+		return nil
+	}
+
+	return errors.New("unsupported network: ", network)
 }

proxy/shadowsocks_2022/packet.go

@@ -0,0 +1,512 @@
+package shadowsocks_2022
+
+import (
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/binary"
+	"io"
+	"math"
+	mrand "math/rand/v2"
+	"sync/atomic"
+	"time"
+
+	"github.com/xtls/xray-core/common/buf"
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/net"
+)
+
+type UDPCodec struct {
+	method           *CipherMethod
+	psk              []byte
+	blockCipher      cipher.Block
+	chachaCipher     cipher.AEAD
+	clientBodyCipher cipher.AEAD
+	clientSessionID  uint64
+	nextPacketID     atomic.Uint64
+	sessions         *UDPSessionManager
+}
+
+type (
+	UDPPacketCodec = UDPCodec
+	UDPServerCodec = UDPCodec
+)
+
+func newUDPCodec(method *CipherMethod, psk []byte) (*UDPCodec, error) {
+	c := &UDPCodec{
+		method: method,
+		psk:    psk,
+	}
+	var err error
+	if method.IsChaCha {
+		c.chachaCipher, err = method.NewUDPCipher(psk)
+	} else {
+		c.blockCipher, err = method.NewBlock(psk)
+	}
+	if err != nil {
+		return nil, err
+	}
+	return c, nil
+}
+
+func NewUDPPacketCodec(method *CipherMethod, psk []byte) (*UDPCodec, error) {
+	c, err := newUDPCodec(method, psk)
+	if err != nil {
+		return nil, err
+	}
+	var sessID [8]byte
+	if _, err := io.ReadFull(rand.Reader, sessID[:]); err != nil {
+		return nil, err
+	}
+	c.clientSessionID = binary.BigEndian.Uint64(sessID[:])
+
+	if !method.IsChaCha {
+		clientBodyKey := DeriveSessionSubKey(psk, sessID[:], method.KeySaltLength)
+		c.clientBodyCipher, err = method.NewAEAD(clientBodyKey)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return c, nil
+}
+
+func NewUDPServerCodec(method *CipherMethod, psk []byte, sessionTimeout time.Duration) (*UDPCodec, error) {
+	c, err := newUDPCodec(method, psk)
+	if err != nil {
+		return nil, err
+	}
+	c.sessions = NewUDPSessionManager(sessionTimeout)
+	return c, nil
+}
+
+func (c *UDPCodec) EncodeClientPacket(dest net.Destination, payload []byte) (*buf.Buffer, error) {
+	packetID := c.nextPacketID.Add(1)
+	sessID := c.clientSessionID
+
+	// Padding determination (e.g. DNS port 53 disguise)
+	var paddingLen int
+	if dest.Port == 53 && len(payload) < MaxPaddingLength {
+		paddingLen = mrand.IntN(MaxPaddingLength-len(payload)) + 1
+	}
+
+	addrPortLen := AddrPortLength(dest)
+
+	if c.method.IsChaCha {
+		// ChaCha20 mode: 24-byte nonce + plaintext header (27B) + padding + dest + payload + AEAD tag (16B)
+		totalLen := PacketNonceSize + 27 + paddingLen + addrPortLen + len(payload) + AEADTagSize
+		if totalLen > buf.Size {
+			return nil, ErrPacketTooLarge
+		}
+
+		outBuf := buf.New()
+
+		var nonce [PacketNonceSize]byte
+		if _, err := io.ReadFull(rand.Reader, nonce[:]); err != nil {
+			outBuf.Release()
+			return nil, err
+		}
+		outBuf.Write(nonce[:])
+
+		var hdr [16 + 1 + 8 + 2]byte
+		binary.BigEndian.PutUint64(hdr[0:8], sessID)
+		binary.BigEndian.PutUint64(hdr[8:16], packetID)
+		hdr[16] = HeaderTypeClient
+		binary.BigEndian.PutUint64(hdr[17:25], uint64(time.Now().Unix()))
+		binary.BigEndian.PutUint16(hdr[25:27], uint16(paddingLen))
+		outBuf.Write(hdr[:])
+		if paddingLen > 0 {
+			outBuf.Write(zeroPadding[:paddingLen])
+		}
+
+		if err := WriteAddressPort(outBuf, dest); err != nil {
+			outBuf.Release()
+			return nil, err
+		}
+		outBuf.Write(payload)
+
+		plainBytes := outBuf.Bytes()[PacketNonceSize:]
+		outBuf.Extend(int32(c.chachaCipher.Overhead()))
+		c.chachaCipher.Seal(plainBytes[:0], nonce[:], plainBytes, nil)
+		return outBuf, nil
+	}
+
+	// AES mode:
+	// 16B Encrypted Header + (11B header + padding + dest + payload + 16B AEAD tag)
+	totalLen := 16 + 11 + paddingLen + addrPortLen + len(payload) + AEADTagSize
+	if totalLen > buf.Size {
+		return nil, ErrPacketTooLarge
+	}
+
+	outBuf := buf.New()
+
+	var rawHeader [16]byte
+	binary.BigEndian.PutUint64(rawHeader[:8], sessID)
+	binary.BigEndian.PutUint64(rawHeader[8:16], packetID)
+
+	var encryptedHeader [16]byte
+	c.blockCipher.Encrypt(encryptedHeader[:], rawHeader[:])
+	outBuf.Write(encryptedHeader[:])
+
+	bodyAead := c.clientBodyCipher
+
+	var hdr [1 + 8 + 2]byte
+	hdr[0] = HeaderTypeClient
+	binary.BigEndian.PutUint64(hdr[1:9], uint64(time.Now().Unix()))
+	binary.BigEndian.PutUint16(hdr[9:11], uint16(paddingLen))
+	outBuf.Write(hdr[:])
+	if paddingLen > 0 {
+		outBuf.Write(zeroPadding[:paddingLen])
+	}
+
+	if err := WriteAddressPort(outBuf, dest); err != nil {
+		outBuf.Release()
+		return nil, err
+	}
+	outBuf.Write(payload)
+
+	plainBytes := outBuf.Bytes()[16:]
+	bodyNonce := rawHeader[4:16]
+	outBuf.Extend(int32(bodyAead.Overhead()))
+	bodyAead.Seal(plainBytes[:0], bodyNonce, plainBytes, nil)
+	return outBuf, nil
+}
+
+type DecodedUDPPacket struct {
+	SessionID   uint64
+	PacketID    uint64
+	HeaderType  byte
+	Timestamp   uint64
+	Destination net.Destination
+	Payload     []byte
+}
+
+func parseAddressPort(data []byte) (net.Destination, int, error) {
+	if len(data) < 1 {
+		return net.Destination{}, 0, ErrPacketTooShort
+	}
+	switch data[0] {
+	case 1: // IPv4
+		if len(data) < 1+4+2 {
+			return net.Destination{}, 0, ErrPacketTooShort
+		}
+		ip := net.IPAddress(data[1:5])
+		port := binary.BigEndian.Uint16(data[5:7])
+		return net.UDPDestination(ip, net.Port(port)), 7, nil
+	case 4: // IPv6
+		if len(data) < 1+16+2 {
+			return net.Destination{}, 0, ErrPacketTooShort
+		}
+		ip := net.IPAddress(data[1:17])
+		port := binary.BigEndian.Uint16(data[17:19])
+		return net.UDPDestination(ip, net.Port(port)), 19, nil
+	case 3: // Domain
+		if len(data) < 2 {
+			return net.Destination{}, 0, ErrPacketTooShort
+		}
+		domainLen := int(data[1])
+		if len(data) < 2+domainLen+2 {
+			return net.Destination{}, 0, ErrPacketTooShort
+		}
+		domain := string(data[2 : 2+domainLen])
+		port := binary.BigEndian.Uint16(data[2+domainLen : 2+domainLen+2])
+		return net.UDPDestination(net.DomainAddress(domain), net.Port(port)), 2 + domainLen + 2, nil
+	default:
+		return net.Destination{}, 0, errors.New("unknown address type")
+	}
+}
+
+func parsePlainUDPPacket(sessionID, packetID uint64, bodyPlain []byte) (DecodedUDPPacket, error) {
+	if len(bodyPlain) < 1+8+2 {
+		return DecodedUDPPacket{}, ErrPacketTooShort
+	}
+
+	headerType := bodyPlain[0]
+	epoch := binary.BigEndian.Uint64(bodyPlain[1:9])
+	diff := int(math.Abs(float64(time.Now().Unix() - int64(epoch))))
+	if diff > 30 {
+		return DecodedUDPPacket{}, ErrBadTimestamp
+	}
+
+	offset := 9
+	if headerType == HeaderTypeServer {
+		if len(bodyPlain) < offset+8+2 {
+			return DecodedUDPPacket{}, ErrPacketTooShort
+		}
+		offset += 8 // skip clientSessionID
+	}
+
+	paddingLen := int(binary.BigEndian.Uint16(bodyPlain[offset : offset+2]))
+	offset += 2
+
+	if len(bodyPlain) < offset+paddingLen {
+		return DecodedUDPPacket{}, ErrNoPadding
+	}
+	offset += paddingLen
+
+	dest, addrLen, err := parseAddressPort(bodyPlain[offset:])
+	if err != nil {
+		return DecodedUDPPacket{}, err
+	}
+	payload := bodyPlain[offset+addrLen:]
+
+	return DecodedUDPPacket{
+		SessionID:   sessionID,
+		PacketID:    packetID,
+		HeaderType:  headerType,
+		Timestamp:   epoch,
+		Destination: dest,
+		Payload:     payload,
+	}, nil
+}
+
+func (c *UDPCodec) DecodePacket(data []byte) (DecodedUDPPacket, error) {
+	if len(data) < PacketMinimalHeaderSize {
+		return DecodedUDPPacket{}, ErrPacketTooShort
+	}
+
+	if c.method.IsChaCha {
+		if len(data) < PacketNonceSize+AEADTagSize {
+			return DecodedUDPPacket{}, ErrPacketTooShort
+		}
+		nonce := data[:PacketNonceSize]
+		ciphertext := data[PacketNonceSize:]
+		plain, err := c.chachaCipher.Open(ciphertext[:0], nonce, ciphertext, nil)
+		if err != nil {
+			return DecodedUDPPacket{}, errors.New("failed to decrypt chacha udp packet").Base(err)
+		}
+		if len(plain) < 16+1+8+2 {
+			return DecodedUDPPacket{}, ErrPacketTooShort
+		}
+
+		sessionID := binary.BigEndian.Uint64(plain[:8])
+		packetID := binary.BigEndian.Uint64(plain[8:16])
+
+		if c.sessions != nil {
+			sessionItem := c.sessions.GetOrCreate(sessionID)
+			sessionItem.Lock()
+			if !sessionItem.Window.CheckAndAdd(packetID) {
+				sessionItem.Unlock()
+				return DecodedUDPPacket{}, ErrPacketIdNotUnique
+			}
+			sessionItem.Unlock()
+		}
+
+		return parsePlainUDPPacket(sessionID, packetID, plain[16:])
+	}
+
+	// AES mode
+	var rawHeader [16]byte
+	c.blockCipher.Decrypt(rawHeader[:], data[:16])
+	sessionID := binary.BigEndian.Uint64(rawHeader[:8])
+	packetID := binary.BigEndian.Uint64(rawHeader[8:16])
+
+	var bodyAead cipher.AEAD
+	var sessionItem *ServerUDPSession
+
+	if c.sessions != nil {
+		sessionItem = c.sessions.GetOrCreate(sessionID)
+		sessionItem.Lock()
+		if !sessionItem.Window.Check(packetID) {
+			sessionItem.Unlock()
+			return DecodedUDPPacket{}, ErrPacketIdNotUnique
+		}
+		sessionItem.Unlock()
+
+		bodyAead = sessionItem.GetRemoteCipher()
+		if bodyAead == nil {
+			bodyKey := DeriveSessionSubKey(c.psk, rawHeader[:8], c.method.KeySaltLength)
+			var err error
+			bodyAead, err = c.method.NewAEAD(bodyKey)
+			if err != nil {
+				return DecodedUDPPacket{}, err
+			}
+			sessionItem.SetRemoteCipher(bodyAead)
+		}
+	} else {
+		bodyKey := DeriveSessionSubKey(c.psk, rawHeader[:8], c.method.KeySaltLength)
+		var err error
+		bodyAead, err = c.method.NewAEAD(bodyKey)
+		if err != nil {
+			return DecodedUDPPacket{}, err
+		}
+	}
+
+	bodyNonce := rawHeader[4:16]
+	bodyCipher := data[16:]
+	bodyPlain, err := bodyAead.Open(bodyCipher[:0], bodyNonce, bodyCipher, nil)
+	if err != nil {
+		return DecodedUDPPacket{}, errors.New("failed to decrypt aes udp body").Base(err)
+	}
+
+	if sessionItem != nil {
+		sessionItem.Lock()
+		sessionItem.Window.Add(packetID)
+		sessionItem.Unlock()
+	}
+
+	return parsePlainUDPPacket(sessionID, packetID, bodyPlain)
+}
+
+func (s *ServerUDPSession) EnsureServerState(method *CipherMethod, headerBlock cipher.Block, chachaCipher cipher.AEAD, psk []byte) error {
+	s.Lock()
+	defer s.Unlock()
+	if s.ServerSessionID != 0 {
+		return nil
+	}
+	var sidBuf [8]byte
+	for {
+		if _, err := io.ReadFull(rand.Reader, sidBuf[:]); err != nil {
+			return err
+		}
+		s.ServerSessionID = binary.BigEndian.Uint64(sidBuf[:])
+		if s.ServerSessionID != 0 {
+			break
+		}
+	}
+	if method.IsChaCha {
+		s.ServerChaCha = chachaCipher
+	} else {
+		s.ServerBlockCipher = headerBlock
+		bodyKey := DeriveSessionSubKey(psk, sidBuf[:], method.KeySaltLength)
+		bodyAead, err := method.NewAEAD(bodyKey)
+		if err != nil {
+			s.ServerSessionID = 0
+			return err
+		}
+		s.ServerCipher = bodyAead
+	}
+	return nil
+}
+
+func (s *ServerUDPSession) EncodeServerPacket(method *CipherMethod, clientSessionID uint64, dest net.Destination, payload []byte) ([]byte, error) {
+	serverSessionID := s.ServerSessionID
+	serverPacketID := s.ServerPacketID.Add(1)
+
+	if method.IsChaCha {
+		var nonce [PacketNonceSize]byte
+		if _, err := io.ReadFull(rand.Reader, nonce[:]); err != nil {
+			return nil, err
+		}
+
+		plainBuf := buf.New()
+		defer plainBuf.Release()
+
+		var hdr [16 + 1 + 8 + 8 + 2]byte
+		binary.BigEndian.PutUint64(hdr[0:8], serverSessionID)
+		binary.BigEndian.PutUint64(hdr[8:16], serverPacketID)
+		hdr[16] = HeaderTypeServer
+		binary.BigEndian.PutUint64(hdr[17:25], uint64(time.Now().Unix()))
+		binary.BigEndian.PutUint64(hdr[25:33], clientSessionID)
+		binary.BigEndian.PutUint16(hdr[33:35], 0)
+		plainBuf.Write(hdr[:])
+
+		if err := WriteAddressPort(plainBuf, dest); err != nil {
+			return nil, err
+		}
+		plainBuf.Write(payload)
+
+		sealed := s.ServerChaCha.Seal(nil, nonce[:], plainBuf.Bytes(), nil)
+		res := make([]byte, PacketNonceSize+len(sealed))
+		copy(res[:PacketNonceSize], nonce[:])
+		copy(res[PacketNonceSize:], sealed)
+		return res, nil
+	}
+
+	// AES mode
+	var rawHeader [16]byte
+	binary.BigEndian.PutUint64(rawHeader[:8], serverSessionID)
+	binary.BigEndian.PutUint64(rawHeader[8:16], serverPacketID)
+
+	var encryptedHeader [16]byte
+	s.ServerBlockCipher.Encrypt(encryptedHeader[:], rawHeader[:])
+
+	bodyBuf := buf.New()
+	defer bodyBuf.Release()
+
+	var hdr [1 + 8 + 8 + 2]byte
+	hdr[0] = HeaderTypeServer
+	binary.BigEndian.PutUint64(hdr[1:9], uint64(time.Now().Unix()))
+	binary.BigEndian.PutUint64(hdr[9:17], clientSessionID)
+	binary.BigEndian.PutUint16(hdr[17:19], 0)
+	bodyBuf.Write(hdr[:])
+
+	if err := WriteAddressPort(bodyBuf, dest); err != nil {
+		return nil, err
+	}
+	bodyBuf.Write(payload)
+
+	bodyNonce := rawHeader[4:16]
+	sealedBody := s.ServerCipher.Seal(nil, bodyNonce, bodyBuf.Bytes(), nil)
+
+	res := make([]byte, 16+len(sealedBody))
+	copy(res[:16], encryptedHeader[:])
+	copy(res[16:], sealedBody)
+	return res, nil
+}
+
+func (c *UDPCodec) EncodeServerPacket(clientSessionID uint64, dest net.Destination, payload []byte) ([]byte, error) {
+	sessionItem := c.sessions.GetOrCreate(clientSessionID)
+	if err := sessionItem.EnsureServerState(c.method, c.blockCipher, c.chachaCipher, c.psk); err != nil {
+		return nil, err
+	}
+	return sessionItem.EncodeServerPacket(c.method, clientSessionID, dest, payload)
+}
+
+type UDPWriter struct {
+	Writer      io.Writer
+	Destination net.Destination
+	Codec       *UDPPacketCodec
+}
+
+func (w *UDPWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
+	for {
+		mb2, b := buf.SplitFirst(mb)
+		mb = mb2
+		if b == nil {
+			break
+		}
+		dest := w.Destination
+		if b.UDP != nil {
+			dest = *b.UDP
+		}
+		pktBuf, err := w.Codec.EncodeClientPacket(dest, b.Bytes())
+		b.Release()
+		if err != nil {
+			buf.ReleaseMulti(mb)
+			return err
+		}
+		_, writeErr := w.Writer.Write(pktBuf.Bytes())
+		pktBuf.Release()
+		if writeErr != nil {
+			buf.ReleaseMulti(mb)
+			return writeErr
+		}
+	}
+	return nil
+}
+
+type UDPReader struct {
+	Reader io.Reader
+	Codec  *UDPPacketCodec
+}
+
+func (r *UDPReader) ReadMultiBuffer() (buf.MultiBuffer, error) {
+	for {
+		buffer := buf.New()
+		_, err := buffer.ReadFrom(r.Reader)
+		if err != nil {
+			buffer.Release()
+			return nil, err
+		}
+
+		decoded, err := r.Codec.DecodePacket(buffer.Bytes())
+		if err != nil {
+			buffer.Release()
+			continue
+		}
+		buffer.Clear()
+		buffer.Write(decoded.Payload)
+		dest := decoded.Destination
+		buffer.UDP = &dest
+		return buf.MultiBuffer{buffer}, nil
+	}
+}

proxy/shadowsocks_2022/relay_test.go

@@ -0,0 +1,271 @@
+package shadowsocks_2022_test
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/binary"
+	"errors"
+	gonet "net"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/buf"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/features/routing"
+	. "github.com/xtls/xray-core/proxy/shadowsocks_2022"
+	"github.com/xtls/xray-core/transport"
+	"lukechampine.com/blake3"
+)
+
+// encodeRelayClientUDPPacket encodes a Shadowsocks-2022 UDP packet with 1 layer of EIH (Relay)
+func encodeRelayClientUDPPacket(relayKey, destKey []byte, sessionID, packetID uint64, dest net.Destination, payload []byte) ([]byte, error) {
+	method, err := GetCipherMethod(MethodAES128GCM)
+	if err != nil {
+		return nil, err
+	}
+	relayBlock, err := method.NewBlock(relayKey)
+	if err != nil {
+		return nil, err
+	}
+
+	// 1. Plain packet header: sessionID (8B) + packetID (8B)
+	var rawHeader [16]byte
+	binary.BigEndian.PutUint64(rawHeader[:8], sessionID)
+	binary.BigEndian.PutUint64(rawHeader[8:16], packetID)
+
+	// Encrypt packetHeader under relayKey
+	var encPacketHeader [16]byte
+	relayBlock.Encrypt(encPacketHeader[:], rawHeader[:])
+
+	// 2. EI Header: blake3(destKey)[:16] ^ rawHeader
+	var destHash [16]byte
+	hash512 := blake3.Sum512(destKey)
+	copy(destHash[:], hash512[:16])
+
+	var eiHeader [16]byte
+	for i := 0; i < 16; i++ {
+		eiHeader[i] = destHash[i] ^ rawHeader[i]
+	}
+	var encEIHeader [16]byte
+	relayBlock.Encrypt(encEIHeader[:], eiHeader[:])
+
+	// 3. Payload under destination server's AEAD
+	bodyKey := DeriveSessionSubKey(destKey, rawHeader[:8], 16)
+	bodyAead, err := method.NewAEAD(bodyKey)
+	if err != nil {
+		return nil, err
+	}
+	bodyNonce := rawHeader[4:16]
+
+	outBuf := buf.New()
+	defer outBuf.Release()
+
+	// VarHeader: client type (1) + timestamp (8) + paddingLen (2) + padding + dest + payload
+	var hdr [1 + 8 + 2]byte
+	hdr[0] = HeaderTypeClient
+	binary.BigEndian.PutUint64(hdr[1:9], uint64(time.Now().Unix()))
+	binary.BigEndian.PutUint16(hdr[9:11], 0)
+	outBuf.Write(hdr[:])
+
+	if err := WriteAddressPort(outBuf, dest); err != nil {
+		return nil, err
+	}
+	outBuf.Write(payload)
+
+	plainBytes := outBuf.Bytes()
+	outBuf.Extend(int32(bodyAead.Overhead()))
+	bodyAead.Seal(plainBytes[:0], bodyNonce, plainBytes, nil)
+
+	// Full packet: encPacketHeader (16B) + encEIHeader (16B) + sealedBody
+	packet := make([]byte, 0, 32+outBuf.Len())
+	packet = append(packet, encPacketHeader[:]...)
+	packet = append(packet, encEIHeader[:]...)
+	packet = append(packet, outBuf.Bytes()...)
+	return packet, nil
+}
+
+func TestRelayUDPSessionStabilityAndDispatch(t *testing.T) {
+	relayKey := []byte("0123456789abcdef")
+	destKey := []byte("fedcba9876543210")
+	relayKeyB64 := base64.StdEncoding.EncodeToString(relayKey)
+	destKeyB64 := base64.StdEncoding.EncodeToString(destKey)
+
+	config := &RelayServerConfig{
+		Method: MethodAES128GCM,
+		Key:    relayKeyB64,
+		Destinations: []*RelayDestination{
+			{
+				Key:     destKeyB64,
+				Address: &net.IPOrDomain{Address: &net.IPOrDomain_Ip{Ip: []byte{127, 0, 0, 1}}},
+				Port:    8388,
+				Email:   "dest@example.com",
+			},
+		},
+	}
+
+	inbound, err := NewRelayServer(newTestContext(), config)
+	if err != nil {
+		t.Fatalf("failed to create RelayServer: %v", err)
+	}
+
+	sessionID := uint64(0x1122334455667788)
+	dest := net.UDPDestination(net.LocalHostIP, 8388)
+
+	pkt1, err := encodeRelayClientUDPPacket(relayKey, destKey, sessionID, 1, dest, []byte("xray packet 1"))
+	if err != nil {
+		t.Fatalf("failed to encode pkt1: %v", err)
+	}
+	pkt2, err := encodeRelayClientUDPPacket(relayKey, destKey, sessionID, 2, dest, []byte("xray packet 2"))
+	if err != nil {
+		t.Fatalf("failed to encode pkt2: %v", err)
+	}
+
+	var dispatchCount atomic.Int32
+	var receivedPackets [][]byte
+	var mu sync.Mutex
+
+	disp := &dummyDispatcher{
+		onDispatch: func(ctx context.Context, d net.Destination) (*transport.Link, error) {
+			dispatchCount.Add(1)
+			linkR, linkW := gonet.Pipe()
+			t.Cleanup(func() {
+				linkW.Close()
+				linkR.Close()
+			})
+			link := &transport.Link{
+				Reader: buf.NewReader(linkR),
+				Writer: &customWriter{
+					write: func(mb buf.MultiBuffer) error {
+						mu.Lock()
+						defer mu.Unlock()
+						for _, b := range mb {
+							cpy := make([]byte, b.Len())
+							copy(cpy, b.Bytes())
+							receivedPackets = append(receivedPackets, cpy)
+							b.Release()
+						}
+						return nil
+					},
+				},
+			}
+			return link, nil
+		},
+	}
+
+	clientConn, serverConn := gonet.Pipe()
+	defer clientConn.Close()
+	defer serverConn.Close()
+
+	inboundConn := &dummyStatConn{Conn: serverConn}
+	ctx, cancel := context.WithCancel(newTestContext())
+	defer cancel()
+
+	go func() {
+		_ = inbound.Process(ctx, net.Network_UDP, inboundConn, disp)
+	}()
+
+	// Send Packet 1
+	_, err = clientConn.Write(pkt1)
+	if err != nil {
+		t.Fatalf("write pkt1 failed: %v", err)
+	}
+	time.Sleep(50 * time.Millisecond)
+
+	// Send Packet 2 (same sessionID, packetID=2)
+	_, err = clientConn.Write(pkt2)
+	if err != nil {
+		t.Fatalf("write pkt2 failed: %v", err)
+	}
+	time.Sleep(50 * time.Millisecond)
+
+	// Check dispatch count: For the SAME UDP session, Dispatch MUST be called exactly ONCE!
+	if count := dispatchCount.Load(); count != 1 {
+		t.Fatalf("CRITICAL BUG CONFIRMED: expected dispatchCount = 1 for same session, got %d (sessionID was corrupted by Encrypt!)", count)
+	}
+
+	// Verify downstream destination can decode both packets
+	method, err := GetCipherMethod(MethodAES128GCM)
+	common.Must(err)
+	destCodec, err := NewUDPServerCodec(method, destKey, 300*time.Second)
+	common.Must(err)
+
+	mu.Lock()
+	pkts := receivedPackets
+	mu.Unlock()
+
+	if len(pkts) != 2 {
+		t.Fatalf("expected 2 received packets at destination, got %d", len(pkts))
+	}
+
+	dec1, err := destCodec.DecodePacket(pkts[0])
+	if err != nil {
+		t.Fatalf("dest failed to decode packet 1: %v", err)
+	}
+	if dec1.SessionID != sessionID || dec1.PacketID != 1 || string(dec1.Payload) != "xray packet 1" {
+		t.Fatalf("dec1 mismatch: sess=%x, pktID=%d, payload=%s", dec1.SessionID, dec1.PacketID, string(dec1.Payload))
+	}
+
+	dec2, err := destCodec.DecodePacket(pkts[1])
+	if err != nil {
+		t.Fatalf("dest failed to decode packet 2: %v", err)
+	}
+	if dec2.SessionID != sessionID || dec2.PacketID != 2 || string(dec2.Payload) != "xray packet 2" {
+		t.Fatalf("dec2 mismatch: sess=%x, pktID=%d, payload=%s", dec2.SessionID, dec2.PacketID, string(dec2.Payload))
+	}
+}
+
+type customWriter struct {
+	write func(mb buf.MultiBuffer) error
+}
+
+func (w *customWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
+	return w.write(mb)
+}
+
+func (w *customWriter) Close() error {
+	return nil
+}
+
+func (w *customWriter) Interrupt() {}
+
+type dummyDispatcher struct {
+	onDispatch func(ctx context.Context, dest net.Destination) (*transport.Link, error)
+}
+
+func (d *dummyDispatcher) Dispatch(ctx context.Context, dest net.Destination) (*transport.Link, error) {
+	if d.onDispatch != nil {
+		return d.onDispatch(ctx, dest)
+	}
+	return nil, errors.New("not handled")
+}
+
+func (d *dummyDispatcher) DispatchLink(ctx context.Context, dest net.Destination, link *transport.Link) error {
+	return nil
+}
+
+func (d *dummyDispatcher) Start() error      { return nil }
+func (d *dummyDispatcher) Close() error      { return nil }
+func (d *dummyDispatcher) Type() interface{} { return routing.DispatcherType() }
+
+type dummyStatConn struct {
+	gonet.Conn
+}
+
+func (c *dummyStatConn) ReadMultiBuffer() (buf.MultiBuffer, error) {
+	b := buf.New()
+	_, err := b.ReadFrom(c.Conn)
+	return buf.MultiBuffer{b}, err
+}
+
+func (c *dummyStatConn) WriteMultiBuffer(mb buf.MultiBuffer) error {
+	defer buf.ReleaseMulti(mb)
+	for _, b := range mb {
+		if _, err := c.Conn.Write(b.Bytes()); err != nil {
+			return err
+		}
+	}
+	return nil
+}

proxy/shadowsocks_2022/replay.go

@@ -0,0 +1,158 @@
+package shadowsocks_2022
+
+import (
+	"crypto/cipher"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/xtls/xray-core/common/protocol"
+	"github.com/xtls/xray-core/common/utils"
+)
+
+const (
+	swBlockBitLog = 6                                // 1<<6 == 64 bits
+	swBlockBits   = 1 << swBlockBitLog               // 64
+	swRingBlocks  = 1 << 7                           // 128
+	swBlockMask   = swRingBlocks - 1                 // 127
+	swBitMask     = swBlockBits - 1                  // 63
+	swSize        = (swRingBlocks - 1) * swBlockBits // 8128
+)
+
+type SlidingWindow struct {
+	last uint64
+	ring [swRingBlocks]uint64
+}
+
+func (f *SlidingWindow) Reset() {
+	*f = SlidingWindow{}
+}
+
+func (f *SlidingWindow) Check(counter uint64) bool {
+	switch {
+	case counter > f.last:
+		return true
+	case f.last-counter > swSize:
+		return false
+	}
+
+	blockIndex := (counter >> swBlockBitLog) & swBlockMask
+	bitIndex := counter & swBitMask
+	return (f.ring[blockIndex]>>bitIndex)&1 == 0
+}
+
+func (f *SlidingWindow) Add(counter uint64) {
+	blockIndex := counter >> swBlockBitLog
+
+	if counter > f.last {
+		lastBlockIndex := f.last >> swBlockBitLog
+		diff := int(blockIndex - lastBlockIndex)
+		if diff > swRingBlocks {
+			diff = swRingBlocks
+		}
+
+		for i := 0; i < diff; i++ {
+			lastBlockIndex = (lastBlockIndex + 1) & swBlockMask
+			f.ring[lastBlockIndex] = 0
+		}
+
+		f.last = counter
+	}
+
+	blockIndex &= swBlockMask
+	bitIndex := counter & swBitMask
+	f.ring[blockIndex] |= 1 << bitIndex
+}
+
+func (f *SlidingWindow) CheckAndAdd(counter uint64) bool {
+	if !f.Check(counter) {
+		return false
+	}
+	f.Add(counter)
+	return true
+}
+
+type ServerUDPSession struct {
+	sync.Mutex
+	SessionID    uint64
+	RemoteCipher atomic.Pointer[cipher.AEAD]
+	Window       SlidingWindow
+	User         *protocol.MemoryUser
+	UserPSK      []byte
+	LastActive   atomic.Int64 // Unix timestamp in seconds
+
+	ServerSessionID   uint64
+	ServerPacketID    atomic.Uint64
+	ServerCipher      cipher.AEAD
+	ServerBlockCipher cipher.Block
+	ServerChaCha      cipher.AEAD
+}
+
+func (s *ServerUDPSession) GetRemoteCipher() cipher.AEAD {
+	ptr := s.RemoteCipher.Load()
+	if ptr == nil {
+		return nil
+	}
+	return *ptr
+}
+
+func (s *ServerUDPSession) SetRemoteCipher(c cipher.AEAD) {
+	s.RemoteCipher.Store(&c)
+}
+
+type UDPSessionManager struct {
+	sessions  *utils.TypedSyncMap[uint64, *ServerUDPSession]
+	timeout   time.Duration
+	lastClean atomic.Int64 // Unix timestamp in seconds
+}
+
+func NewUDPSessionManager(timeout time.Duration) *UDPSessionManager {
+	return &UDPSessionManager{
+		sessions: utils.NewTypedSyncMap[uint64, *ServerUDPSession](),
+		timeout:  timeout,
+	}
+}
+
+func (m *UDPSessionManager) GetOrCreate(sessionID uint64) *ServerUDPSession {
+	now := time.Now().Unix()
+	if s, ok := m.sessions.Load(sessionID); ok {
+		s.LastActive.Store(now)
+		return s
+	}
+
+	s := &ServerUDPSession{
+		SessionID: sessionID,
+	}
+	s.LastActive.Store(now)
+
+	actual, loaded := m.sessions.LoadOrStore(sessionID, s)
+	if loaded {
+		actual.LastActive.Store(now)
+		return actual
+	}
+
+	// Trigger cleanup if at least 30 seconds have passed since last cleanup
+	last := m.lastClean.Load()
+	if now-last > 30 && m.lastClean.CompareAndSwap(last, now) {
+		go m.cleanup(now)
+	}
+
+	return s
+}
+
+func (m *UDPSessionManager) cleanup(now int64) {
+	timeoutSec := int64(m.timeout.Seconds())
+	if timeoutSec <= 0 {
+		timeoutSec = 60
+	}
+	m.sessions.Range(func(k uint64, v *ServerUDPSession) bool {
+		if now-v.LastActive.Load() > timeoutSec {
+			m.sessions.Delete(k)
+		}
+		return true
+	})
+}
+
+func (m *UDPSessionManager) Delete(sessionID uint64) {
+	m.sessions.Delete(sessionID)
+}

proxy/shadowsocks_2022/shadowsocks_2022.go

@@ -1 +1,50 @@
 package shadowsocks_2022
+
+import (
+	"context"
+	"sync"
+
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/signal"
+	"github.com/xtls/xray-core/transport"
+)
+
+type udpConnEntry struct {
+	sync.Mutex
+	link   *transport.Link
+	timer  *signal.ActivityTimer
+	cancel context.CancelFunc
+}
+
+const (
+	HeaderTypeClient              = 0
+	HeaderTypeServer              = 1
+	MaxPaddingLength              = 900
+	PacketNonceSize               = 24
+	MaxPacketSize                 = 65535
+	RequestHeaderFixedChunkLength = 1 + 8 + 2 // Type (1B) + Timestamp (8B) + VarHeaderLen (2B)
+	PacketMinimalHeaderSize       = 30
+	StreamNonceSize               = 12
+	AESBlockSize                  = 16
+	AEADTagSize                   = 16
+)
+
+var zeroPadding [MaxPaddingLength]byte
+
+const (
+	MethodAES128GCM        = "2022-blake3-aes-128-gcm"
+	MethodAES256GCM        = "2022-blake3-aes-256-gcm"
+	MethodChaCha20Poly1305 = "2022-blake3-chacha20-poly1305"
+)
+
+var (
+	ErrBadKey            = errors.New("bad key")
+	ErrBadHeaderType     = errors.New("bad header type")
+	ErrBadTimestamp      = errors.New("bad timestamp")
+	ErrSaltNotUnique     = errors.New("salt not unique")
+	ErrPacketIdNotUnique = errors.New("packet id not unique")
+	ErrPacketTooShort    = errors.New("packet too short")
+	ErrPacketTooLarge    = errors.New("packet too large")
+	ErrNoPadding         = errors.New("bad request: missing payload or padding")
+	ErrInvalidRequest    = errors.New("invalid request")
+)

proxy/shadowsocks_2022/shadowsocks_2022_test.go

@@ -0,0 +1,362 @@
+package shadowsocks_2022_test
+
+import (
+	"bytes"
+	"context"
+	"crypto/rand"
+	"encoding/base64"
+	"encoding/binary"
+	"io"
+	gonet "net"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/buf"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/common/protocol"
+	"github.com/xtls/xray-core/common/serial"
+	"github.com/xtls/xray-core/common/session"
+	"github.com/xtls/xray-core/core"
+	. "github.com/xtls/xray-core/proxy/shadowsocks_2022"
+)
+
+func newTestContext() context.Context {
+	v, err := core.New(&core.Config{})
+	common.Must(err)
+	ctx := context.WithValue(context.Background(), core.XrayKey(1), v)
+	ctx = session.ContextWithInbound(ctx, &session.Inbound{})
+	return ctx
+}
+
+func generateRandomKey(size int) string {
+	b := make([]byte, size)
+	_, _ = rand.Read(b)
+	return base64.StdEncoding.EncodeToString(b)
+}
+
+func TestKDF(t *testing.T) {
+	// Test ParseKey
+	if _, err := ParseKey("", 16); err != ErrBadKey {
+		t.Fatalf("expected ErrBadKey for empty key, got %v", err)
+	}
+
+	shortKey := base64.StdEncoding.EncodeToString([]byte("short"))
+	if _, err := ParseKey(shortKey, 16); err != ErrBadKey {
+		t.Fatalf("expected ErrBadKey for short key, got %v", err)
+	}
+
+	exactKey := []byte("0123456789abcdef")
+	exactKeyB64 := base64.StdEncoding.EncodeToString(exactKey)
+	normExact, err := ParseKey(exactKeyB64, 16)
+	if err != nil || !bytes.Equal(normExact, exactKey) {
+		t.Fatalf("unexpected parsed exact key: %v, err: %v", normExact, err)
+	}
+
+	longKey := base64.StdEncoding.EncodeToString([]byte("0123456789abcdef_longer_key_for_testing"))
+	if _, err := ParseKey(longKey, 16); err != ErrBadKey {
+		t.Fatalf("expected ErrBadKey for long key, got %v", err)
+	}
+
+	// Test Session Subkey determinism
+	salt := []byte("random_salt_1234")
+	k1 := DeriveSessionSubKey(normExact, salt, 16)
+	k2 := DeriveSessionSubKey(normExact, salt, 16)
+	if !bytes.Equal(k1, k2) {
+		t.Fatal("DeriveSessionSubKey should be deterministic")
+	}
+
+	// Identity subkey must differ from session subkey with same inputs
+	idKey := DeriveIdentitySubKey(normExact, salt, 16)
+	if bytes.Equal(k1, idKey) {
+		t.Fatal("DeriveIdentitySubKey must differ from DeriveSessionSubKey")
+	}
+
+	// User PSK hash
+	h1 := DeriveUserPSKHash(normExact)
+	h2 := DeriveUserPSKHash(normExact)
+	if h1 != h2 {
+		t.Fatal("DeriveUserPSKHash should be deterministic")
+	}
+}
+
+func TestSlidingWindow(t *testing.T) {
+	var window SlidingWindow
+	if !window.Check(1) {
+		t.Fatal("packet 1 should be accepted")
+	}
+	window.Add(1)
+
+	if window.Check(1) {
+		t.Fatal("duplicate packet 1 should be rejected")
+	}
+
+	if !window.Check(100) {
+		t.Fatal("packet 100 should be accepted")
+	}
+	window.Add(100)
+
+	if window.Check(100) {
+		t.Fatal("duplicate packet 100 should be rejected")
+	}
+
+	if !window.Check(50) {
+		t.Fatal("out-of-order packet 50 within window should be accepted")
+	}
+	window.Add(50)
+	if window.Check(50) {
+		t.Fatal("duplicate packet 50 should be rejected")
+	}
+
+	// Check packet far behind window (> 8128)
+	window.Add(10000)
+	if window.Check(1) {
+		t.Fatal("packet 1 should be rejected as behind window")
+	}
+}
+
+func TestTCPStream(t *testing.T) {
+	methods := []struct {
+		name    string
+		keySize int
+	}{
+		{MethodAES128GCM, 16},
+		{MethodAES256GCM, 32},
+		{MethodChaCha20Poly1305, 32},
+	}
+
+	dest := net.TCPDestination(net.LocalHostIP, net.Port(8080))
+	testPayload := []byte("Hello, Shadowsocks 2022 Native Implementation!")
+
+	for _, m := range methods {
+		t.Run(m.name, func(t *testing.T) {
+			rawKey := make([]byte, m.keySize)
+			_, _ = rand.Read(rawKey)
+			method, err := GetCipherMethod(m.name)
+			common.Must(err)
+
+			clientConn, serverConn := gonet.Pipe()
+			defer clientConn.Close()
+			defer serverConn.Close()
+
+			var wg sync.WaitGroup
+			wg.Add(2)
+
+			var receivedDest net.Destination
+			var receivedPayload []byte
+
+			// Server goroutine
+			go func() {
+				defer wg.Done()
+				salt := make([]byte, method.KeySaltLength)
+				_, err := io.ReadFull(serverConn, salt)
+				common.Must(err)
+
+				sessionKey := DeriveSessionSubKey(rawKey, salt, method.KeySaltLength)
+				aead, err := method.NewAEAD(sessionKey)
+				common.Must(err)
+
+				reader := NewStreamReader(serverConn, aead)
+
+				// Read fixed chunk (11 + 16 bytes)
+				var fixedBuf [RequestHeaderFixedChunkLength + AEADTagSize]byte
+				_, err = io.ReadFull(serverConn, fixedBuf[:])
+				common.Must(err)
+
+				plainFixed, err := aead.Open(fixedBuf[:0], reader.Nonce(), fixedBuf[:], nil)
+				common.Must(err)
+				IncreaseNonce(reader.Nonce())
+				if plainFixed[0] != HeaderTypeClient {
+					t.Errorf("expected client header type, got %d", plainFixed[0])
+				}
+
+				// Read variable chunk
+				varLen := int(plainFixed[9])<<8 | int(plainFixed[10])
+				varBuf := make([]byte, varLen+AEADTagSize)
+				_, err = io.ReadFull(serverConn, varBuf)
+				common.Must(err)
+
+				plainVar, err := aead.Open(varBuf[:0], reader.Nonce(), varBuf, nil)
+				common.Must(err)
+				IncreaseNonce(reader.Nonce())
+
+				vBuf := buf.New()
+				vBuf.Write(plainVar)
+				receivedDest, err = ReadAddressPort(vBuf)
+				common.Must(err)
+
+				// Skip padding
+				var padBytes [2]byte
+				_, _ = vBuf.Read(padBytes[:])
+				padLen := int(padBytes[0])<<8 | int(padBytes[1])
+				vBuf.Advance(int32(padLen))
+
+				receivedPayload = make([]byte, vBuf.Len())
+				copy(receivedPayload, vBuf.Bytes())
+				vBuf.Release()
+
+				// Server sends response handshake
+				serverSalt := make([]byte, method.KeySaltLength)
+				_, _ = rand.Read(serverSalt)
+				respKey := DeriveSessionSubKey(rawKey, serverSalt, method.KeySaltLength)
+				respAead, err := method.NewAEAD(respKey)
+				writer := NewStreamWriter(serverConn, respAead)
+				_, _ = serverConn.Write(serverSalt)
+
+				fixedResp := make([]byte, 1+8+method.KeySaltLength+2)
+				fixedResp[0] = HeaderTypeServer
+				binary.BigEndian.PutUint64(fixedResp[1:9], uint64(time.Now().Unix()))
+				copy(fixedResp[9:9+method.KeySaltLength], salt)
+				binary.BigEndian.PutUint16(fixedResp[9+method.KeySaltLength:11+method.KeySaltLength], 0)
+
+				fixedChunk := respAead.Seal(nil, writer.Nonce(), fixedResp, nil)
+				IncreaseNonce(writer.Nonce())
+				_, _ = serverConn.Write(fixedChunk)
+
+				// Echo stream data
+				mb, err := reader.ReadMultiBuffer()
+				common.Must(err)
+				_ = writer.WriteMultiBuffer(mb)
+			}()
+
+			// Client goroutine
+			go func() {
+				defer wg.Done()
+				clientSalt, writer, err := ClientHandshake(clientConn, method, [][]byte{rawKey}, dest, testPayload)
+				common.Must(err)
+
+				reader, _, err := ClientVerifyServerResponse(clientConn, method, rawKey, clientSalt)
+				common.Must(err)
+
+				// Send additional stream data
+				streamData := []byte("stream chunk test")
+				_ = writer.WriteChunk(streamData)
+
+				mb, err := reader.ReadMultiBuffer()
+				common.Must(err)
+				if !bytes.Equal(mb[0].Bytes(), streamData) {
+					t.Errorf("echoed stream data mismatch: got %s, want %s", mb[0].Bytes(), streamData)
+				}
+				buf.ReleaseMulti(mb)
+			}()
+
+			wg.Wait()
+
+			if receivedDest.NetAddr() != dest.NetAddr() {
+				t.Errorf("destination mismatch: got %s, want %s", receivedDest.NetAddr(), dest.NetAddr())
+			}
+			if diff := cmp.Diff(receivedPayload, testPayload); diff != "" {
+				t.Errorf("payload mismatch: %s", diff)
+			}
+		})
+	}
+}
+
+func TestUDPCodec(t *testing.T) {
+	methods := []string{
+		MethodAES128GCM,
+		MethodAES256GCM,
+		MethodChaCha20Poly1305,
+	}
+
+	dest := net.UDPDestination(net.LocalHostIP, net.Port(53))
+	payload := []byte("DNS query payload")
+
+	for _, methodName := range methods {
+		t.Run(methodName, func(t *testing.T) {
+			method, err := GetCipherMethod(methodName)
+			common.Must(err)
+
+			psk := make([]byte, method.KeySaltLength)
+			_, _ = rand.Read(psk)
+
+			clientCodec, err := NewUDPPacketCodec(method, psk)
+			common.Must(err)
+			serverCodec, err := NewUDPServerCodec(method, psk, time.Minute)
+			common.Must(err)
+
+			pktBuf, err := clientCodec.EncodeClientPacket(dest, payload)
+			common.Must(err)
+			defer pktBuf.Release()
+
+			rawCopy := make([]byte, pktBuf.Len())
+			copy(rawCopy, pktBuf.Bytes())
+
+			decoded, err := serverCodec.DecodePacket(pktBuf.Bytes())
+			common.Must(err)
+
+			if decoded.HeaderType != HeaderTypeClient {
+				t.Errorf("expected header type %d, got %d", HeaderTypeClient, decoded.HeaderType)
+			}
+			if decoded.Destination.Port != dest.Port {
+				t.Errorf("port mismatch: got %d, want %d", decoded.Destination.Port, dest.Port)
+			}
+			if !bytes.Equal(decoded.Payload, payload) {
+				t.Errorf("payload mismatch: got %s, want %s", decoded.Payload, payload)
+			}
+
+			// Replay same packet wire bytes should fail with ErrPacketIdNotUnique
+			_, err = serverCodec.DecodePacket(rawCopy)
+			if err != ErrPacketIdNotUnique {
+				t.Fatalf("expected ErrPacketIdNotUnique on replay, got: %v", err)
+			}
+		})
+	}
+}
+
+func TestMultiUserManager(t *testing.T) {
+	masterKey := generateRandomKey(16)
+	userKey1 := generateRandomKey(16)
+	userKey2 := generateRandomKey(16)
+
+	config := &MultiUserServerConfig{
+		Method: MethodAES128GCM,
+		Key:    masterKey,
+		Users: []*protocol.User{
+			{
+				Email:   "user1@example.com",
+				Account: serial.ToTypedMessage(&Account{Key: userKey1}),
+			},
+		},
+	}
+
+	inbound, err := NewMultiServer(newTestContext(), config)
+	common.Must(err)
+
+	if inbound.GetUsersCount(context.Background()) != 1 {
+		t.Fatalf("expected 1 user, got %d", inbound.GetUsersCount(context.Background()))
+	}
+
+	u1 := inbound.GetUser(context.Background(), "user1@example.com")
+	if u1 == nil || u1.Email != "user1@example.com" {
+		t.Fatal("user1 not found")
+	}
+
+	// Add User 2
+	rawKey2, _ := base64.StdEncoding.DecodeString(userKey2)
+	u2 := &protocol.MemoryUser{
+		Email: "user2@example.com",
+		Account: &MemoryAccount{
+			Key: rawKey2,
+		},
+	}
+	err = inbound.AddUser(context.Background(), u2)
+	common.Must(err)
+
+	if inbound.GetUsersCount(context.Background()) != 2 {
+		t.Fatalf("expected 2 users, got %d", inbound.GetUsersCount(context.Background()))
+	}
+
+	// Remove User 1
+	err = inbound.RemoveUser(context.Background(), "user1@example.com")
+	common.Must(err)
+
+	if inbound.GetUsersCount(context.Background()) != 1 {
+		t.Fatalf("expected 1 user, got %d", inbound.GetUsersCount(context.Background()))
+	}
+	if inbound.GetUser(context.Background(), "user1@example.com") != nil {
+		t.Fatal("user1 should have been removed")
+	}
+}

proxy/shadowsocks_2022/stream.go

@@ -0,0 +1,529 @@
+package shadowsocks_2022
+
+import (
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/binary"
+	"io"
+	"math"
+	mrand "math/rand/v2"
+	"time"
+
+	"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/protocol"
+)
+
+var addrParser = protocol.NewAddressParser(
+	protocol.AddressFamilyByte(0x01, net.AddressFamilyIPv4),
+	protocol.AddressFamilyByte(0x04, net.AddressFamilyIPv6),
+	protocol.AddressFamilyByte(0x03, net.AddressFamilyDomain),
+	protocol.WithAddressTypeParser(func(b byte) byte {
+		return b & 0x0F
+	}),
+)
+
+func IncreaseNonce(nonce []byte) {
+	for i := range nonce {
+		nonce[i]++
+		if nonce[i] != 0 {
+			return
+		}
+	}
+}
+
+// WriteAddressPort writes a destination address and port in SOCKS5 format
+func WriteAddressPort(w io.Writer, dest net.Destination) error {
+	return addrParser.WriteAddressPort(w, dest.Address, dest.Port)
+}
+
+// ReadAddressPort reads a destination address and port in SOCKS5 format
+func ReadAddressPort(r io.Reader) (net.Destination, error) {
+	addr, port, err := addrParser.ReadAddressPort(nil, r)
+	if err != nil {
+		return net.Destination{}, err
+	}
+	return net.TCPDestination(addr, port), nil
+}
+
+// AddrPortLength returns the serialized length of a destination in SOCKS5 format
+func AddrPortLength(dest net.Destination) int {
+	switch dest.Address.Family() {
+	case net.AddressFamilyIPv4:
+		return 1 + 4 + 2
+	case net.AddressFamilyDomain:
+		return 1 + 1 + len(dest.Address.Domain()) + 2
+	case net.AddressFamilyIPv6:
+		return 1 + 16 + 2
+	default:
+		return 0
+	}
+}
+
+type StreamWriter struct {
+	writer io.Writer
+	cipher cipher.AEAD
+	nonce  [StreamNonceSize]byte
+	lenBuf [2]byte
+	buf    []byte
+}
+
+func NewStreamWriter(w io.Writer, c cipher.AEAD) *StreamWriter {
+	return &StreamWriter{
+		writer: w,
+		cipher: c,
+		buf:    make([]byte, 0, MaxPacketSize+2+2*AEADTagSize),
+	}
+}
+
+func (w *StreamWriter) Nonce() []byte {
+	return w.nonce[:]
+}
+
+func (w *StreamWriter) WriteChunk(payload []byte) error {
+	payloadLen := len(payload)
+	if payloadLen == 0 {
+		return nil
+	}
+	if payloadLen > MaxPacketSize {
+		return errors.New("payload exceeds MaxPacketSize")
+	}
+
+	binary.BigEndian.PutUint16(w.lenBuf[:], uint16(payloadLen))
+	w.buf = w.cipher.Seal(w.buf[:0], w.nonce[:], w.lenBuf[:], nil)
+	IncreaseNonce(w.nonce[:])
+
+	w.buf = w.cipher.Seal(w.buf, w.nonce[:], payload, nil)
+	IncreaseNonce(w.nonce[:])
+
+	_, err := w.writer.Write(w.buf)
+	return err
+}
+
+func (w *StreamWriter) Write(p []byte) (int, error) {
+	n := len(p)
+	for len(p) > 0 {
+		chunkSize := len(p)
+		if chunkSize > MaxPacketSize {
+			chunkSize = MaxPacketSize
+		}
+		if err := w.WriteChunk(p[:chunkSize]); err != nil {
+			return 0, err
+		}
+		p = p[chunkSize:]
+	}
+	return n, nil
+}
+
+func (w *StreamWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
+	defer buf.ReleaseMulti(mb)
+	for _, b := range mb {
+		if err := w.WriteChunk(b.Bytes()); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+type StreamReader struct {
+	reader io.Reader
+	cipher cipher.AEAD
+	nonce  [StreamNonceSize]byte
+	lenBuf [2 + AEADTagSize]byte
+	buffer []byte
+	cached int
+	offset int
+}
+
+func NewStreamReader(r io.Reader, c cipher.AEAD) *StreamReader {
+	return &StreamReader{
+		reader: r,
+		cipher: c,
+		buffer: make([]byte, MaxPacketSize+AEADTagSize),
+	}
+}
+
+func (r *StreamReader) Nonce() []byte {
+	return r.nonce[:]
+}
+
+func (r *StreamReader) Read(p []byte) (int, error) {
+	if r.cached > 0 {
+		n := copy(p, r.buffer[r.offset:r.offset+r.cached])
+		r.cached -= n
+		r.offset += n
+		return n, nil
+	}
+
+	// Read 2-byte length + AEAD tag (18 bytes)
+	if _, err := io.ReadFull(r.reader, r.lenBuf[:]); err != nil {
+		return 0, err
+	}
+
+	decryptedLen, err := r.cipher.Open(r.lenBuf[:0], r.nonce[:], r.lenBuf[:], nil)
+	if err != nil {
+		return 0, errors.New("failed to decrypt chunk length").Base(err)
+	}
+	IncreaseNonce(r.nonce[:])
+
+	payloadLen := int(binary.BigEndian.Uint16(decryptedLen))
+	if payloadLen == 0 {
+		return 0, ErrInvalidRequest
+	}
+
+	chunkEnd := payloadLen + AEADTagSize
+	if _, err := io.ReadFull(r.reader, r.buffer[:chunkEnd]); err != nil {
+		return 0, err
+	}
+
+	decryptedPayload, err := r.cipher.Open(r.buffer[:0], r.nonce[:], r.buffer[:chunkEnd], nil)
+	if err != nil {
+		return 0, errors.New("failed to decrypt chunk payload").Base(err)
+	}
+	IncreaseNonce(r.nonce[:])
+
+	r.cached = len(decryptedPayload)
+	r.offset = 0
+
+	n := copy(p, r.buffer[r.offset:r.offset+r.cached])
+	r.cached -= n
+	r.offset += n
+	return n, nil
+}
+
+func (r *StreamReader) ReadMultiBuffer() (buf.MultiBuffer, error) {
+	if r.cached > 0 {
+		b := buf.New()
+		b.Write(r.buffer[r.offset : r.offset+r.cached])
+		r.cached = 0
+		r.offset = 0
+		return buf.MultiBuffer{b}, nil
+	}
+
+	if _, err := io.ReadFull(r.reader, r.lenBuf[:]); err != nil {
+		return nil, err
+	}
+
+	decryptedLen, err := r.cipher.Open(r.lenBuf[:0], r.nonce[:], r.lenBuf[:], nil)
+	if err != nil {
+		return nil, errors.New("failed to decrypt chunk length").Base(err)
+	}
+	IncreaseNonce(r.nonce[:])
+
+	payloadLen := int(binary.BigEndian.Uint16(decryptedLen))
+	if payloadLen == 0 {
+		return nil, ErrInvalidRequest
+	}
+
+	chunkEnd := payloadLen + AEADTagSize
+	if _, err := io.ReadFull(r.reader, r.buffer[:chunkEnd]); err != nil {
+		return nil, err
+	}
+
+	decryptedPayload, err := r.cipher.Open(r.buffer[:0], r.nonce[:], r.buffer[:chunkEnd], nil)
+	if err != nil {
+		return nil, errors.New("failed to decrypt chunk payload").Base(err)
+	}
+	IncreaseNonce(r.nonce[:])
+
+	b := buf.New()
+	b.Write(decryptedPayload)
+	return buf.MultiBuffer{b}, nil
+}
+
+type ClientRequestHeader struct {
+	Destination net.Destination
+	EarlyData   []byte
+}
+
+func ReadClientRequestHeader(conn io.Reader, reader *StreamReader) (*ClientRequestHeader, error) {
+	var fixedBuf [RequestHeaderFixedChunkLength + AEADTagSize]byte
+	if _, err := io.ReadFull(conn, fixedBuf[:]); err != nil {
+		return nil, err
+	}
+
+	plainFixed, err := reader.cipher.Open(fixedBuf[:0], reader.Nonce(), fixedBuf[:], nil)
+	if err != nil {
+		return nil, errors.New("failed to decrypt client request header").Base(err)
+	}
+	IncreaseNonce(reader.Nonce())
+
+	if plainFixed[0] != HeaderTypeClient {
+		return nil, ErrBadHeaderType
+	}
+
+	epoch := binary.BigEndian.Uint64(plainFixed[1:9])
+	diff := int(math.Abs(float64(time.Now().Unix() - int64(epoch))))
+	if diff > 30 {
+		return nil, ErrBadTimestamp
+	}
+
+	varHeaderLen := int(binary.BigEndian.Uint16(plainFixed[9:11]))
+	if varHeaderLen == 0 {
+		return nil, ErrInvalidRequest
+	}
+
+	var stackVarChunk [512]byte
+	var varChunkCipher []byte
+	needed := varHeaderLen + AEADTagSize
+	if needed <= len(stackVarChunk) {
+		varChunkCipher = stackVarChunk[:needed]
+	} else {
+		varChunkCipher = make([]byte, needed)
+	}
+	if _, err := io.ReadFull(conn, varChunkCipher); err != nil {
+		return nil, err
+	}
+
+	plainVar, err := reader.cipher.Open(varChunkCipher[:0], reader.Nonce(), varChunkCipher, nil)
+	if err != nil {
+		return nil, errors.New("failed to decrypt variable request header").Base(err)
+	}
+	IncreaseNonce(reader.Nonce())
+
+	b := buf.New()
+	b.Write(plainVar)
+	defer b.Release()
+
+	dest, err := ReadAddressPort(b)
+	if err != nil {
+		return nil, err
+	}
+
+	var padLenBytes [2]byte
+	if _, err := b.Read(padLenBytes[:]); err != nil {
+		return nil, err
+	}
+	paddingLen := int(binary.BigEndian.Uint16(padLenBytes[:]))
+	if int(b.Len()) < paddingLen {
+		return nil, ErrNoPadding
+	}
+	if paddingLen > 0 {
+		b.Advance(int32(paddingLen))
+	}
+
+	var earlyData []byte
+	if b.Len() > 0 {
+		earlyData = make([]byte, b.Len())
+		copy(earlyData, b.Bytes())
+	}
+
+	return &ClientRequestHeader{
+		Destination: dest,
+		EarlyData:   earlyData,
+	}, nil
+}
+
+// ClientHandshake writes the full client request header to w
+func ClientHandshake(w io.Writer, method *CipherMethod, pskList [][]byte, dest net.Destination, payload []byte) ([]byte, *StreamWriter, error) {
+	salt := make([]byte, method.KeySaltLength)
+	if _, err := io.ReadFull(rand.Reader, salt); err != nil {
+		return nil, nil, err
+	}
+	writer, err := WriteTCPRequest(w, method, pskList, dest, salt, payload)
+	if err != nil {
+		return nil, nil, err
+	}
+	return salt, writer.(*StreamWriter), nil
+}
+
+// ClientVerifyServerResponse reads and verifies the server's handshake response
+func ClientVerifyServerResponse(r io.Reader, method *CipherMethod, psk []byte, clientSalt []byte) (*StreamReader, []byte, error) {
+	reader, err := ReadTCPResponse(r, method, psk, clientSalt)
+	if err != nil {
+		return nil, nil, err
+	}
+	sr := reader.(*StreamReader)
+	var initialPayload []byte
+	if sr.cached > 0 {
+		initialPayload = make([]byte, sr.cached)
+		copy(initialPayload, sr.buffer[sr.offset:sr.offset+sr.cached])
+	}
+	return sr, initialPayload, nil
+}
+
+// WriteTCPRequest writes the Shadowsocks 2022 request header into w and returns a body writer.
+func WriteTCPRequest(w io.Writer, method *CipherMethod, pskList [][]byte, dest net.Destination, clientSalt []byte, payload []byte) (buf.Writer, error) {
+	finalPSK := pskList[len(pskList)-1]
+	sessionKey := DeriveSessionSubKey(finalPSK, clientSalt, method.KeySaltLength)
+	aead, err := method.NewAEAD(sessionKey)
+	if err != nil {
+		return nil, err
+	}
+
+	writer := NewStreamWriter(w, aead)
+
+	handshakeBuf := buf.New()
+	defer handshakeBuf.Release()
+
+	handshakeBuf.Write(clientSalt)
+
+	for i, currPSK := range pskList[:len(pskList)-1] {
+		identitySubkey := DeriveIdentitySubKey(currPSK, clientSalt, method.KeySaltLength)
+		block, err := method.NewBlock(identitySubkey)
+		if err != nil {
+			return nil, err
+		}
+		nextPSK := pskList[i+1]
+		pskHash := DeriveUserPSKHash(nextPSK)
+		var encryptedEIH [AESBlockSize]byte
+		block.Encrypt(encryptedEIH[:], pskHash[:])
+		handshakeBuf.Write(encryptedEIH[:])
+	}
+
+	payloadLen := len(payload)
+	var paddingLen int
+	if payloadLen < MaxPaddingLength {
+		paddingLen = mrand.IntN(MaxPaddingLength-payloadLen) + 1
+	}
+	addrPortLen := AddrPortLength(dest)
+	varHeaderLen := addrPortLen + 2 + paddingLen + payloadLen
+
+	var fixedHeaderPlaintext [RequestHeaderFixedChunkLength]byte
+	fixedHeaderPlaintext[0] = HeaderTypeClient
+	binary.BigEndian.PutUint64(fixedHeaderPlaintext[1:9], uint64(time.Now().Unix()))
+	binary.BigEndian.PutUint16(fixedHeaderPlaintext[9:11], uint16(varHeaderLen))
+
+	fixedChunk := writer.cipher.Seal(nil, writer.nonce[:], fixedHeaderPlaintext[:], nil)
+	IncreaseNonce(writer.nonce[:])
+	handshakeBuf.Write(fixedChunk)
+
+	varHeaderBuf := buf.New()
+	defer varHeaderBuf.Release()
+
+	if err := WriteAddressPort(varHeaderBuf, dest); err != nil {
+		return nil, err
+	}
+
+	var padLenBytes [2]byte
+	binary.BigEndian.PutUint16(padLenBytes[:], uint16(paddingLen))
+	varHeaderBuf.Write(padLenBytes[:])
+
+	if paddingLen > 0 {
+		varHeaderBuf.Write(zeroPadding[:paddingLen])
+	}
+
+	if payloadLen > 0 {
+		varHeaderBuf.Write(payload)
+	}
+
+	varChunk := writer.cipher.Seal(nil, writer.nonce[:], varHeaderBuf.Bytes(), nil)
+	IncreaseNonce(writer.nonce[:])
+	handshakeBuf.Write(varChunk)
+
+	if _, err := w.Write(handshakeBuf.Bytes()); err != nil {
+		return nil, err
+	}
+
+	return writer, nil
+}
+
+// ReadTCPResponse reads and verifies the server's handshake response and returns a reader for the stream.
+func ReadTCPResponse(r io.Reader, method *CipherMethod, psk []byte, clientSalt []byte) (buf.Reader, error) {
+	var serverSalt [32]byte
+	serverSaltSlice := serverSalt[:method.KeySaltLength]
+	if _, err := io.ReadFull(r, serverSaltSlice); err != nil {
+		return nil, err
+	}
+
+	sessionKey := DeriveSessionSubKey(psk, serverSaltSlice, method.KeySaltLength)
+	aead, err := method.NewAEAD(sessionKey)
+	if err != nil {
+		return nil, err
+	}
+
+	reader := NewStreamReader(r, aead)
+
+	fixedPlainLen := 1 + 8 + method.KeySaltLength + 2
+	chunkCipherLen := fixedPlainLen + AEADTagSize
+	var chunkBuf [64]byte
+	chunkSlice := chunkBuf[:chunkCipherLen]
+	if _, err := io.ReadFull(r, chunkSlice); err != nil {
+		return nil, err
+	}
+
+	decryptedFixed, err := reader.cipher.Open(chunkSlice[:0], reader.nonce[:], chunkSlice, nil)
+	if err != nil {
+		return nil, errors.New("failed to decrypt server response header").Base(err)
+	}
+	IncreaseNonce(reader.nonce[:])
+
+	if decryptedFixed[0] != HeaderTypeServer {
+		return nil, ErrBadHeaderType
+	}
+
+	serverEpoch := binary.BigEndian.Uint64(decryptedFixed[1:9])
+	diff := int(math.Abs(float64(time.Now().Unix() - int64(serverEpoch))))
+	if diff > 30 {
+		return nil, ErrBadTimestamp
+	}
+
+	echoedSalt := decryptedFixed[9 : 9+method.KeySaltLength]
+	for i := 0; i < method.KeySaltLength; i++ {
+		if echoedSalt[i] != clientSalt[i] {
+			return nil, errors.New("bad request salt")
+		}
+	}
+
+	initialPayloadLen := int(binary.BigEndian.Uint16(decryptedFixed[9+method.KeySaltLength : 11+method.KeySaltLength]))
+	if initialPayloadLen > 0 {
+		initialCipherLen := initialPayloadLen + AEADTagSize
+		if _, err := io.ReadFull(r, reader.buffer[:initialCipherLen]); err != nil {
+			return nil, err
+		}
+		decryptedInitial, err := reader.cipher.Open(reader.buffer[:0], reader.nonce[:], reader.buffer[:initialCipherLen], nil)
+		if err != nil {
+			return nil, errors.New("failed to decrypt initial response payload").Base(err)
+		}
+		IncreaseNonce(reader.nonce[:])
+		reader.cached = len(decryptedInitial)
+		reader.offset = 0
+	}
+
+	return reader, nil
+}
+
+// WriteTCPResponse writes the server handshake response and returns a body writer for server stream.
+func WriteTCPResponse(w io.Writer, method *CipherMethod, psk []byte, clientSalt []byte, initialPayload []byte) (buf.Writer, error) {
+	var serverSalt [32]byte
+	serverSaltSlice := serverSalt[:method.KeySaltLength]
+	if _, err := io.ReadFull(rand.Reader, serverSaltSlice); err != nil {
+		return nil, err
+	}
+
+	respKey := DeriveSessionSubKey(psk, serverSaltSlice, method.KeySaltLength)
+	respAead, err := method.NewAEAD(respKey)
+	if err != nil {
+		return nil, err
+	}
+	writer := NewStreamWriter(w, respAead)
+
+	respBuf := buf.New()
+	defer respBuf.Release()
+
+	respBuf.Write(serverSaltSlice)
+
+	var fixedRespPlain [1 + 8 + 32 + 2]byte
+	fixedRespSlice := fixedRespPlain[:1+8+method.KeySaltLength+2]
+	fixedRespSlice[0] = HeaderTypeServer
+	binary.BigEndian.PutUint64(fixedRespSlice[1:9], uint64(time.Now().Unix()))
+	copy(fixedRespSlice[9:9+method.KeySaltLength], clientSalt)
+	binary.BigEndian.PutUint16(fixedRespSlice[9+method.KeySaltLength:11+method.KeySaltLength], uint16(len(initialPayload)))
+
+	fixedRespChunk := writer.cipher.Seal(nil, writer.nonce[:], fixedRespSlice, nil)
+	IncreaseNonce(writer.nonce[:])
+	respBuf.Write(fixedRespChunk)
+
+	if len(initialPayload) > 0 {
+		initialChunk := writer.cipher.Seal(nil, writer.nonce[:], initialPayload, nil)
+		IncreaseNonce(writer.nonce[:])
+		respBuf.Write(initialChunk)
+	}
+
+	if _, err := w.Write(respBuf.Bytes()); err != nil {
+		return nil, err
+	}
+
+	return writer, nil
+}

proxy/socks/client.go

@@ -105,7 +105,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 	}
 	udpRequest, err := ClientHandshake(request, conn, conn)
 	if err != nil {
-		return errors.New("failed to establish connection to server").AtWarning().Base(err)
+		return errors.New("failed to establish connection to server").Base(err)
 	}
 	if udpRequest != nil {
 		if udpRequest.Address == net.AnyIP || udpRequest.Address == net.AnyIPv6 {

proxy/socks/protocol.go

@@ -458,10 +458,10 @@ func ClientHandshake(request *protocol.RequestHeader, reader io.Reader, writer i
 	}
 
 	if b.Byte(0) != socks5Version {
-		return nil, errors.New("unexpected server version: ", b.Byte(0)).AtWarning()
+		return nil, errors.New("unexpected server version: ", b.Byte(0))
 	}
 	if b.Byte(1) != authByte {
-		return nil, errors.New("auth method not supported.").AtWarning()
+		return nil, errors.New("auth method not supported.")
 	}
 
 	if authByte == authPassword {

proxy/trojan/client.go

@@ -69,7 +69,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 		return nil
 	})
 	if err != nil {
-		return errors.New("failed to find an available destination").AtWarning().Base(err)
+		return errors.New("failed to find an available destination").Base(err)
 	}
 	errors.LogInfo(ctx, "tunneling request to ", destination, " via ", server.Destination.NetAddr())
 
@@ -116,21 +116,21 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 
 		// write some request payload to buffer
 		if err = buf.CopyOnceTimeout(link.Reader, bodyWriter, time.Millisecond*100); err != nil && err != buf.ErrNotTimeoutReader && err != buf.ErrReadTimeout {
-			return errors.New("failed to write A request payload").Base(err).AtWarning()
+			return errors.New("failed to write A request payload").Base(err)
 		}
 
 		// Flush; bufferWriter.WriteMultiBuffer now is bufferWriter.writer.WriteMultiBuffer
 		if err = bufferWriter.SetBuffered(false); err != nil {
-			return errors.New("failed to flush payload").Base(err).AtWarning()
+			return errors.New("failed to flush payload").Base(err)
 		}
 
 		// Send header if not sent yet
 		if _, err = connWriter.Write([]byte{}); err != nil {
-			return err.(*errors.Error).AtWarning()
+			return err
 		}
 
 		if err = buf.Copy(link.Reader, bodyWriter, buf.UpdateActivity(timer)); err != nil {
-			return errors.New("failed to transfer request payload").Base(err).AtInfo()
+			return errors.New("failed to transfer request payload").Base(err)
 		}
 
 		return nil

proxy/trojan/server.go

@@ -47,11 +47,11 @@ func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) {
 	for _, user := range config.Users {
 		u, err := user.ToMemoryUser()
 		if err != nil {
-			return nil, errors.New("failed to get trojan user").Base(err).AtError()
+			return nil, errors.New("failed to get trojan user").Base(err)
 		}
 
 		if err := validator.Add(u); err != nil {
-			return nil, errors.New("failed to add user").Base(err).AtError()
+			return nil, errors.New("failed to add user").Base(err)
 		}
 	}
 
@@ -151,7 +151,7 @@ func (s *Server) Process(ctx context.Context, network net.Network, conn stat.Con
 
 	sessionPolicy := s.policyManager.ForLevel(0)
 	if err := conn.SetReadDeadline(time.Now().Add(sessionPolicy.Timeouts.Handshake)); err != nil {
-		return errors.New("unable to set read deadline").Base(err).AtWarning()
+		return errors.New("unable to set read deadline").Base(err)
 	}
 
 	first := buf.FromBytes(make([]byte, buf.Size))
@@ -219,7 +219,7 @@ func (s *Server) Process(ctx context.Context, network net.Network, conn stat.Con
 
 	destination := clientReader.Target
 	if err := conn.SetReadDeadline(time.Time{}); err != nil {
-		return errors.New("unable to set read deadline").Base(err).AtWarning()
+		return errors.New("unable to set read deadline").Base(err)
 	}
 
 	inbound := session.InboundFromContext(ctx)
@@ -402,7 +402,7 @@ func (s *Server) fallback(ctx context.Context, err error, sessionPolicy policy.S
 	}
 	apfb := napfb[name]
 	if apfb == nil {
-		return errors.New(`failed to find the default "name" config`).AtWarning()
+		return errors.New(`failed to find the default "name" config`)
 	}
 
 	if apfb[alpn] == nil {
@@ -410,7 +410,7 @@ func (s *Server) fallback(ctx context.Context, err error, sessionPolicy policy.S
 	}
 	pfb := apfb[alpn]
 	if pfb == nil {
-		return errors.New(`failed to find the default "alpn" config`).AtWarning()
+		return errors.New(`failed to find the default "alpn" config`)
 	}
 
 	path := ""
@@ -444,7 +444,7 @@ func (s *Server) fallback(ctx context.Context, err error, sessionPolicy policy.S
 	}
 	fb := pfb[path]
 	if fb == nil {
-		return errors.New(`failed to find the default "path" config`).AtWarning()
+		return errors.New(`failed to find the default "path" config`)
 	}
 
 	ctx, cancel := context.WithCancel(ctx)
@@ -460,7 +460,7 @@ func (s *Server) fallback(ctx context.Context, err error, sessionPolicy policy.S
 		}
 		return nil
 	}); err != nil {
-		return errors.New("failed to dial to " + fb.Dest).Base(err).AtWarning()
+		return errors.New("failed to dial to " + fb.Dest).Base(err)
 	}
 	defer conn.Close()
 
@@ -520,11 +520,11 @@ func (s *Server) fallback(ctx context.Context, err error, sessionPolicy policy.S
 				common.Must2(pro.Write([]byte{byte(p1 >> 8), byte(p1), byte(p2 >> 8), byte(p2)}))
 			}
 			if err := serverWriter.WriteMultiBuffer(buf.MultiBuffer{pro}); err != nil {
-				return errors.New("failed to set PROXY protocol v", fb.Xver).Base(err).AtWarning()
+				return errors.New("failed to set PROXY protocol v", fb.Xver).Base(err)
 			}
 		}
 		if err := buf.Copy(reader, serverWriter, buf.UpdateActivity(timer)); err != nil {
-			return errors.New("failed to fallback request payload").Base(err).AtInfo()
+			return errors.New("failed to fallback request payload").Base(err)
 		}
 		return nil
 	}
@@ -534,7 +534,7 @@ func (s *Server) fallback(ctx context.Context, err error, sessionPolicy policy.S
 	getResponse := func() error {
 		defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
 		if err := buf.Copy(serverReader, writer, buf.UpdateActivity(timer)); err != nil {
-			return errors.New("failed to deliver response payload").Base(err).AtInfo()
+			return errors.New("failed to deliver response payload").Base(err)
 		}
 		return nil
 	}
@@ -542,7 +542,7 @@ func (s *Server) fallback(ctx context.Context, err error, sessionPolicy policy.S
 	if err := task.Run(ctx, task.OnSuccess(postRequest, task.Close(serverWriter)), task.OnSuccess(getResponse, task.Close(writer))); err != nil {
 		common.Must(common.Interrupt(serverReader))
 		common.Must(common.Interrupt(serverWriter))
-		return errors.New("fallback ends").Base(err).AtInfo()
+		return errors.New("fallback ends").Base(err)
 	}
 
 	return nil