TUN inbound: Support "tcp/port" and "udp/port" in autoSystemWfpBlockLeak on Windows; "dns" covers DoT and DoQ as well

"dns" in autoSystemWfpBlockLeak only blocked port 53 outside the TUN, plus
the DNS Client service on Windows 11 and Server 2022 and later, so other
programs' DNS over TLS (TCP 853) and DNS over QUIC (UDP 853) could still
leave outside the TUN.

autoSystemWfpBlockLeak now takes:

- "tcp/<port>", "udp/<port>": connections to that port may only go through
  the TUN (or come from Xray itself).
- "windnsclient": Windows' DNS Client service may only connect through the
  TUN, except for mDNS and LLMNR. As before, this only applies from Windows
  11 and Server 2022 on, where the service may use DoH or DoT to any port;
  earlier versions only query port 53.
- "dns": stands for "udp/53", "tcp/53", "windnsclient", "tcp/853" and
  "udp/853".
- "misconfigtun": unchanged.

Values are case-insensitive, deduplicated, and anything else, such as
"tcp/0" or "icmp/1", is rejected. Keeping the system's DNS inside the TUN,
with "udp/53", "tcp/53" or "windnsclient", needs dns to be set, as "dns"
did; ports like 853 alone do not. Each port gets its own permit-through-TUN
and block filters with a protocol condition, where port 53 used to have one
for both protocols, and the log lists what is blocked, e.g. "[tun] blocked
outside the TUN: udp/53, tcp/53, tcp/853, udp/853, windnsclient".

Tested on Windows 11 with a Wintun adapter as the outside interface: with
"tcp/853", "udp/853", "tcp/7215" and "udp/7216", those are blocked outside
the TUN over IPv4 and IPv6, while tcp/7216, udp/7215 and 443 are not, port
853 works through the TUN, Xray's own connections to port 853 still leave
outside it, and nothing is blocked after Xray stops.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.github/docker/Dockerfile

@@ -9,8 +9,8 @@ ARG TARGETARCH
 RUN GOOS=$TARGETOS GOARCH=$TARGETARCH CGO_ENABLED=0 go build -o xray -trimpath -buildvcs=false -gcflags="all=-l=4" -ldflags "-s -w -buildid=" ./main
 
 # Download geodat into a staging directory
-ADD https://raw.githubusercontent.com/Loyalsoldier/v2ray-rules-dat/release/geoip.dat /tmp/geodat/geoip.dat
-ADD https://raw.githubusercontent.com/Loyalsoldier/v2ray-rules-dat/release/geosite.dat /tmp/geodat/geosite.dat
+ADD https://raw.githubusercontent.com/XTLS/Xray-rules-dat/release/geoip/geoip-full.dat /tmp/geodat/geoip.dat
+ADD https://raw.githubusercontent.com/XTLS/Xray-rules-dat/release/geosite/geosite-expand.dat /tmp/geodat/geosite.dat
 
 RUN mkdir -p /tmp/empty
 
@@ -40,21 +40,15 @@ RUN echo '{}' >/tmp/usr/local/etc/xray/11_geodata.json
 RUN echo '{}' >/tmp/usr/local/etc/xray/12_env.json
 RUN echo '{}' >/tmp/usr/local/etc/xray/99_version.json
 
-# Create log files
-RUN mkdir -p /tmp/var/log/xray && touch \
-  /tmp/var/log/xray/access.log \
-  /tmp/var/log/xray/error.log
-
 # Build finally image
 FROM gcr.io/distroless/static:nonroot
 
 COPY --from=build --chown=0:0 --chmod=755 /src/xray /usr/local/bin/xray
 COPY --from=build --chown=65532:65532 --chmod=755 /tmp/empty /usr/local/share/xray
 COPY --from=build --chown=65532:65532 --chmod=644 /tmp/geodat/*.dat /usr/local/share/xray/
-COPY --from=build --chown=0:0 --chmod=755 /tmp/empty /usr/local/etc/xray
-COPY --from=build --chown=0:0 --chmod=644 /tmp/usr/local/etc/xray/*.json /usr/local/etc/xray/
-COPY --from=build --chown=0:0 --chmod=755 /tmp/empty /var/log/xray
-COPY --from=build --chown=65532:65532 --chmod=600 /tmp/var/log/xray/*.log /var/log/xray/
+COPY --from=build --chown=0:65532 --chmod=750 /tmp/empty /usr/local/etc/xray
+COPY --from=build --chown=0:65532 --chmod=640 /tmp/usr/local/etc/xray/*.json /usr/local/etc/xray/
+COPY --from=build --chown=65532:65532 --chmod=700 /tmp/empty /var/log/xray
 
 VOLUME /usr/local/etc/xray
 VOLUME /var/log/xray

.github/docker/Dockerfile.usa

@@ -9,8 +9,8 @@ ARG TARGETARCH
 RUN GOOS=$TARGETOS GOARCH=$TARGETARCH CGO_ENABLED=0 go build -o xray -trimpath -buildvcs=false -gcflags="all=-l=4" -ldflags "-s -w -buildid=" ./main
 
 # Download geodat into a staging directory
-ADD https://raw.githubusercontent.com/Loyalsoldier/v2ray-rules-dat/release/geoip.dat /tmp/geodat/geoip.dat
-ADD https://raw.githubusercontent.com/Loyalsoldier/v2ray-rules-dat/release/geosite.dat /tmp/geodat/geosite.dat
+ADD https://raw.githubusercontent.com/XTLS/Xray-rules-dat/release/geoip/geoip-full.dat /tmp/geodat/geoip.dat
+ADD https://raw.githubusercontent.com/XTLS/Xray-rules-dat/release/geosite/geosite-expand.dat /tmp/geodat/geosite.dat
 
 RUN mkdir -p /tmp/empty
 
@@ -40,11 +40,6 @@ RUN echo '{}' >/tmp/usr/local/etc/xray/11_geodata.json
 RUN echo '{}' >/tmp/usr/local/etc/xray/12_env.json
 RUN echo '{}' >/tmp/usr/local/etc/xray/99_version.json
 
-# Create log files
-RUN mkdir -p /tmp/var/log/xray && touch \
-  /tmp/var/log/xray/access.log \
-  /tmp/var/log/xray/error.log
-
 # Build finally image
 # Note on Distroless Base Image and Architecture Support:
 # - The official 'gcr.io/distroless/static' image provided by Google only supports a limited set of architectures for Linux:
@@ -60,10 +55,9 @@ FROM --platform=linux/amd64 gcr.io/distroless/static:nonroot
 COPY --from=build --chown=0:0 --chmod=755 /src/xray /usr/local/bin/xray
 COPY --from=build --chown=65532:65532 --chmod=755 /tmp/empty /usr/local/share/xray
 COPY --from=build --chown=65532:65532 --chmod=644 /tmp/geodat/*.dat /usr/local/share/xray/
-COPY --from=build --chown=0:0 --chmod=755 /tmp/empty /usr/local/etc/xray
-COPY --from=build --chown=0:0 --chmod=644 /tmp/usr/local/etc/xray/*.json /usr/local/etc/xray/
-COPY --from=build --chown=0:0 --chmod=755 /tmp/empty /var/log/xray
-COPY --from=build --chown=65532:65532 --chmod=600 /tmp/var/log/xray/*.log /var/log/xray/
+COPY --from=build --chown=0:65532 --chmod=750 /tmp/empty /usr/local/etc/xray
+COPY --from=build --chown=0:65532 --chmod=640 /tmp/usr/local/etc/xray/*.json /usr/local/etc/xray/
+COPY --from=build --chown=65532:65532 --chmod=700 /tmp/empty /var/log/xray
 
 VOLUME /usr/local/etc/xray
 VOLUME /var/log/xray

.github/workflows/docker.yml

@@ -82,7 +82,7 @@ jobs:
         uses: docker/setup-buildx-action@v4
 
       - name: Login to GitHub Container Registry
-        uses: docker/login-action@v4.6.0
+        uses: docker/login-action@v4.7.0
         with:
           registry: ghcr.io
           username: ${{ github.repository_owner }}

.github/workflows/scheduled-assets-update.yml

@@ -40,7 +40,7 @@ jobs:
           max_attempts: 60
           command: |
             [ -d 'resources' ] || mkdir resources
-            LIST=('Loyalsoldier v2ray-rules-dat geoip geoip' 'Loyalsoldier v2ray-rules-dat geosite geosite')
+            LIST=('XTLS Xray-rules-dat geoip/geoip-lite geoip' 'XTLS Xray-rules-dat geosite/geosite geosite')
             for i in "${LIST[@]}"
             do
               INFO=($(echo $i | awk 'BEGIN{FS=" ";OFS=" "} {print $1,$2,$3,$4}'))

.github/workflows/test.yml

@@ -35,24 +35,7 @@ jobs:
         if: steps.check-assets.outputs.missing == 'true'
         run: sleep 90
 
-  check-proto:
-    runs-on: ubuntu-latest
-    if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
-    steps:
-      - name: Checkout codebase
-        uses: actions/checkout@v7
-      - name: Check Proto Version Header
-        run: |
-          head -n 4 core/config.pb.go > ref.txt
-          find . -name "*.pb.go" ! -name "*_grpc.pb.go" -print0 | while IFS= read -r -d '' file; do
-            if ! cmp -s ref.txt <(head -n 4 "$file"); then
-              echo "Error: Header mismatch in $file"
-              head -n 4 "$file"
-              exit 1
-            fi
-          done
-
-  check-format:
+  check-format-and-proto:
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     permissions:
@@ -68,6 +51,8 @@ jobs:
           cache: false
       - name: Check Format
         run: go run ./infra/vformat/main.go -mode check -pwd ./
+      - name: Check Protobuf
+        run: go run ./infra/vprotogen/main.go -mode check -pwd ./
 
   test:
     needs: check-assets

app/dns/script_test.go

@@ -128,7 +128,7 @@ func TestDNSScriptGeoIPFallback(t *testing.T) {
 	t.Setenv("xray.location.asset", filepath.Join("..", "..", "resources"))
 	script := `
 local servers = require("xray.dns").Servers
-local us_ips = require("xray.geodata").BuildIPMatcher("geoip:us")
+local ru_ips = require("xray.geodata").BuildIPMatcher("geoip:ru")
 
 local by_id = {}
 for _, server in ipairs(servers) do
@@ -138,7 +138,7 @@ assert(by_id.primary and by_id.fallback, "primary and fallback DNS servers are r
 
 function HandleDNSQuery(domain, ipv4, ipv6, fake)
     local ips, ttl, err = by_id.primary:Query(domain, ipv4, ipv6, fake)
-    if not err and us_ips:AnyMatch(ips) then
+    if not err and ru_ips:AnyMatch(ips) then
         return ips, ttl, nil
     end
     return by_id.fallback:Query(domain, ipv4, ipv6, fake)
@@ -152,7 +152,7 @@ end
 	primary := &scriptNameServer{
 		name: "primary",
 		answers: map[string]net.IP{
-			"us.example":    net.ParseIP("2001:4860:4860::8888"),
+			"ru.example":    net.ParseIP("2a02:6b8::feed:0ff"),
 			"other.example": net.ParseIP("127.0.0.1"),
 		},
 		ttl: 30,
@@ -191,7 +191,7 @@ end
 		ip     net.IP
 		ttl    uint32
 	}{
-		{"Us.Example.", net.ParseIP("2001:4860:4860::8888"), 30},
+		{"Ru.Example.", net.ParseIP("2a02:6b8::feed:0ff"), 30},
 		{"other.example", net.ParseIP("9.9.9.9"), 60},
 	} {
 		ips, ttl, err := server.LookupIP(tc.domain, option)

app/geodata/download.go

@@ -21,7 +21,10 @@ import (
 	"golang.org/x/net/http2"
 )
 
-const idleTimeout = 30 * time.Second
+const (
+	idleTimeout           = 30 * time.Second
+	maxDownloadSize int64 = 256 * 1024 * 1024
+)
 
 // DO NOT EDIT. Ignored by geodata, rejected by Lua.
 const luaGuardHeader = "\x12\x01\x00"
@@ -33,7 +36,6 @@ type stage struct {
 
 type downloader struct {
 	ctx         context.Context
-	httpClient  *http.Client
 	httpsClient *http.Client
 }
 
@@ -61,12 +63,11 @@ func (c *idleConn) Write(b []byte) (int, error) {
 func newDownloader(ctx context.Context, dispatcher routing.Dispatcher, outbound string) *downloader {
 	return &downloader{
 		ctx:         ctx,
-		httpClient:  newClient(ctx, dispatcher, outbound, false),
-		httpsClient: newClient(ctx, dispatcher, outbound, true),
+		httpsClient: newClient(ctx, dispatcher, outbound),
 	}
 }
 
-func newClient(baseCtx context.Context, dispatcher routing.Dispatcher, outbound string, isHTTPS bool) *http.Client {
+func newClient(baseCtx context.Context, dispatcher routing.Dispatcher, outbound string) *http.Client {
 	dial := func(ctx context.Context, network, address string) (net.Conn, error) {
 		var conn net.Conn
 		err := task.Run(ctx, func() error {
@@ -91,53 +92,33 @@ func newClient(baseCtx context.Context, dispatcher routing.Dispatcher, outbound
 			Conn: conn,
 		}, nil
 	}
-	if isHTTPS {
-		return &http.Client{
-			Transport: &http2.Transport{
-				DialTLSContext: func(ctx context.Context, network string, address string, cfg *tls.Config) (net.Conn, error) {
-					conn, err := dial(ctx, network, address)
-					if err != nil {
-						return nil, err
-					}
-					host, _, _ := net.SplitHostPort(address)
-					tlsConn := utls.UClient(conn, &utls.Config{ServerName: host}, utls.HelloChrome_Auto)
-					handshakeCtx, cancel := context.WithTimeout(ctx, idleTimeout)
-					defer cancel()
-					if err := tlsConn.HandshakeContext(handshakeCtx); err != nil {
-						conn.Close()
-						return nil, err
-					}
-					return tlsConn, nil
-				},
-			},
-			CheckRedirect: func(req *http.Request, via []*http.Request) error {
-				if req.URL.Scheme != "https" {
-					return errors.New("redirected to non-https URL: ", req.URL.String())
+	return &http.Client{
+		Transport: &http2.Transport{
+			DialTLSContext: func(ctx context.Context, network string, address string, cfg *tls.Config) (net.Conn, error) {
+				conn, err := dial(ctx, network, address)
+				if err != nil {
+					return nil, err
 				}
-				if len(via) >= 10 {
-					return errors.New("stopped after 10 redirects")
+				host, _, _ := net.SplitHostPort(address)
+				tlsConn := utls.UClient(conn, &utls.Config{ServerName: host}, utls.HelloChrome_Auto)
+				handshakeCtx, cancel := context.WithTimeout(ctx, idleTimeout)
+				defer cancel()
+				if err := tlsConn.HandshakeContext(handshakeCtx); err != nil {
+					conn.Close()
+					return nil, err
 				}
-				return nil
+				return tlsConn, nil
 			},
-		}
-	} else {
-		return &http.Client{
-			Transport: &http.Transport{
-				Proxy:                 nil,
-				DisableKeepAlives:     true,
-				DialContext:           dial,
-				ResponseHeaderTimeout: idleTimeout,
-			},
-			CheckRedirect: func(req *http.Request, via []*http.Request) error {
-				if req.URL.Scheme != "https" {
-					return errors.New("redirected to non-https URL: ", req.URL.String())
-				}
-				if len(via) >= 10 {
-					return errors.New("stopped after 10 redirects")
-				}
-				return nil
-			},
-		}
+		},
+		CheckRedirect: func(req *http.Request, via []*http.Request) error {
+			if req.URL.Scheme != "https" {
+				return errors.New("redirected to non-https URL: ", req.URL.String())
+			}
+			if len(via) >= 20 {
+				return errors.New("stopped after 20 redirects")
+			}
+			return nil
+		},
 	}
 }
 
@@ -203,27 +184,26 @@ func (d *downloader) fetch(rawURL string, writer io.Writer) error {
 	}
 	utils.TryDefaultHeadersWith(req.Header, "nav")
 
-	var client *http.Client
-	if req.URL.Scheme == "https" {
-		client = d.httpsClient
-	} else {
-		client = d.httpClient
-	}
-	resp, err := client.Do(req)
+	resp, err := d.httpsClient.Do(req)
 	if err != nil {
 		return err
 	}
 	defer resp.Body.Close()
 
 	if resp.StatusCode < http.StatusOK || resp.StatusCode >= http.StatusMultipleChoices {
-		io.Copy(io.Discard, resp.Body)
 		return errors.New("unexpected status code: ", resp.StatusCode)
 	}
+	if resp.ContentLength > maxDownloadSize {
+		return errors.New("geodata download exceeds 256 MiB")
+	}
 
-	n, err := io.Copy(writer, resp.Body)
+	n, err := io.Copy(writer, io.LimitReader(resp.Body, maxDownloadSize+1))
 	if err != nil {
 		return err
 	}
+	if n > maxDownloadSize {
+		return errors.New("geodata download exceeds 256 MiB")
+	}
 	if n == 0 {
 		return errors.New("empty response body")
 	}

app/geodata/download_test.go

@@ -7,10 +7,13 @@ import (
 	"net/http/httptest"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 
 	commongeodata "github.com/xtls/xray-core/common/geodata"
 	xlua "github.com/xtls/xray-core/common/lua"
+	"github.com/xtls/xray-core/common/serial"
+	"github.com/xtls/xray-core/core"
 	"github.com/yuin/gopher-lua/parse"
 	"google.golang.org/protobuf/proto"
 )
@@ -31,11 +34,11 @@ func TestDownloadOneLuaGuard(t *testing.T) {
 			if err := os.WriteFile(filepath.Join(dir, "asset.lua"), nil, 0o600); err != nil {
 				t.Fatal(err)
 			}
-			server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
+			server := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
 				_, _ = w.Write([]byte(tc.body))
 			}))
 			defer server.Close()
-			d := &downloader{ctx: context.Background(), httpClient: server.Client()}
+			d := &downloader{ctx: context.Background(), httpsClient: server.Client()}
 			staged, err := d.downloadOne(&Asset{Url: server.URL, File: "asset.lua"})
 			if err != nil {
 				t.Fatal(err)
@@ -71,3 +74,53 @@ func TestDownloadOneLuaGuard(t *testing.T) {
 		})
 	}
 }
+
+func TestProtobufConfigValidation(t *testing.T) {
+	dir := t.TempDir()
+	t.Setenv("xray.location.asset", dir)
+	for _, name := range []string{"asset.dat", "asset.DAT"} {
+		if err := os.WriteFile(filepath.Join(dir, name), nil, 0o600); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := os.Mkdir(filepath.Join(dir, "directory.dat"), 0o700); err != nil {
+		t.Fatal(err)
+	}
+	server, err := core.New(&core.Config{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _ = server.Close() })
+	for _, tc := range []struct {
+		name      string
+		config    *Config
+		wantError string
+	}{
+		{"minutely cron", &Config{Cron: "* * * * *"}, ""},
+		{"minimum interval", &Config{Cron: "@every 1m"}, ""},
+		{"short interval", &Config{Cron: "@every 59s"}, "interval must be at least 1 minute"},
+		{"fractional interval", &Config{Cron: "@every 59.999s"}, "interval must be at least 1 minute"},
+		{"invalid cron", &Config{Cron: "invalid"}, "invalid geodata cron"},
+		{"dat extension", &Config{Cron: "@daily", Assets: []*Asset{{Url: "https://example.com/asset.dat", File: "asset.dat"}}}, ""},
+		{"uppercase extension", &Config{Cron: "@daily", Assets: []*Asset{{Url: "https://example.com/asset.dat", File: "asset.DAT"}}}, ""},
+		{"invalid extension", &Config{Cron: "@daily", Assets: []*Asset{{Url: "https://example.com/asset.dat", File: "asset.lua"}}}, "extension must be .dat"},
+		{"missing extension", &Config{Cron: "@daily", Assets: []*Asset{{Url: "https://example.com/asset.dat", File: "asset"}}}, "extension must be .dat"},
+		{"missing file", &Config{Cron: "@daily", Assets: []*Asset{{Url: "https://example.com/asset.dat", File: "missing.dat"}}}, "invalid geodata asset file"},
+		{"directory", &Config{Cron: "@daily", Assets: []*Asset{{Url: "https://example.com/asset.dat", File: "directory.dat"}}}, "asset is not a regular file"},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			config, err := serial.ToTypedMessage(tc.config).GetInstance()
+			if err != nil {
+				t.Fatal(err)
+			}
+			_, err = core.CreateObject(server, config)
+			if tc.wantError == "" {
+				if err != nil {
+					t.Fatal(err)
+				}
+			} else if err == nil || !strings.Contains(err.Error(), tc.wantError) {
+				t.Fatalf("CreateObject() error = %v; want %q", err, tc.wantError)
+			}
+		})
+	}
+}

app/geodata/geodata.go

@@ -2,12 +2,16 @@ package geodata
 
 import (
 	"context"
+	"path/filepath"
+	"strings"
 	"sync"
+	"time"
 
 	"github.com/robfig/cron/v3"
 	"github.com/xtls/xray-core/common"
 	"github.com/xtls/xray-core/common/errors"
 	commongeodata "github.com/xtls/xray-core/common/geodata"
+	"github.com/xtls/xray-core/common/platform/filesystem"
 	"github.com/xtls/xray-core/core"
 	"github.com/xtls/xray-core/features/routing"
 )
@@ -25,6 +29,24 @@ func New(ctx context.Context, config *Config) (*Instance, error) {
 	if config.Cron == "" {
 		return &Instance{}, nil
 	}
+	if len(config.Assets) > 100 {
+		return nil, errors.New("geodata supports at most 100 assets")
+	}
+	for _, asset := range config.Assets {
+		if !strings.EqualFold(filepath.Ext(asset.GetFile()), ".dat") {
+			return nil, errors.New("geodata asset file extension must be .dat")
+		}
+		if _, err := filesystem.ResolveAsset(asset.GetFile()); err != nil {
+			return nil, errors.New("invalid geodata asset file: ", asset.GetFile()).Base(err)
+		}
+	}
+	schedule, err := cron.ParseStandard(config.Cron)
+	if err != nil {
+		return nil, errors.New("invalid geodata cron").Base(err)
+	}
+	if interval, ok := schedule.(cron.ConstantDelaySchedule); ok && interval.Delay < time.Minute {
+		return nil, errors.New("geodata cron interval must be at least 1 minute")
+	}
 
 	g := &Instance{
 		assets: config.Assets,
@@ -44,9 +66,7 @@ func New(ctx context.Context, config *Config) (*Instance, error) {
 		cron.WithChain(cron.SkipIfStillRunning(cron.DiscardLogger)),
 		cron.WithLogger(cron.DiscardLogger),
 	)
-	if _, err := g.tasker.AddFunc(config.Cron, g.execute); err != nil {
-		return nil, errors.New("invalid geodata cron").Base(err)
-	}
+	g.tasker.Schedule(schedule, cron.FuncJob(g.execute))
 	errors.LogInfo(ctx, "scheduled geodata reload with cron: ", config.Cron)
 
 	return g, nil

app/observatory/config.pb.go

@@ -152,23 +152,23 @@ func (x *HealthPingMeasurementResult) GetMin() int64 {
 type OutboundStatus struct {
 	state protoimpl.MessageState `protogen:"open.v1"`
 	// @Document Whether this outbound is usable
-	// @Restriction ReadOnlyForUser
+	//@Restriction ReadOnlyForUser
 	Alive bool `protobuf:"varint,1,opt,name=alive,proto3" json:"alive,omitempty"`
 	// @Document The time for probe request to finish.
-	// @Type time.ms
-	// @Restriction ReadOnlyForUser
+	//@Type time.ms
+	//@Restriction ReadOnlyForUser
 	Delay int64 `protobuf:"varint,2,opt,name=delay,proto3" json:"delay,omitempty"`
 	// @Document The last error caused this outbound failed to relay probe request
-	// @Restriction NotMachineReadable
+	//@Restriction NotMachineReadable
 	LastErrorReason string `protobuf:"bytes,3,opt,name=last_error_reason,json=lastErrorReason,proto3" json:"last_error_reason,omitempty"`
 	// @Document The outbound tag for this Server
-	// @Type id.outboundTag
+	//@Type id.outboundTag
 	OutboundTag string `protobuf:"bytes,4,opt,name=outbound_tag,json=outboundTag,proto3" json:"outbound_tag,omitempty"`
 	// @Document The time this outbound is known to be alive
-	// @Type id.outboundTag
+	//@Type id.outboundTag
 	LastSeenTime int64 `protobuf:"varint,5,opt,name=last_seen_time,json=lastSeenTime,proto3" json:"last_seen_time,omitempty"`
 	// @Document The time this outbound is tried
-	// @Type id.outboundTag
+	//@Type id.outboundTag
 	LastTryTime   int64                        `protobuf:"varint,6,opt,name=last_try_time,json=lastTryTime,proto3" json:"last_try_time,omitempty"`
 	HealthPing    *HealthPingMeasurementResult `protobuf:"bytes,7,opt,name=health_ping,json=healthPing,proto3" json:"health_ping,omitempty"`
 	unknownFields protoimpl.UnknownFields
@@ -257,14 +257,14 @@ func (x *OutboundStatus) GetHealthPing() *HealthPingMeasurementResult {
 type ProbeResult struct {
 	state protoimpl.MessageState `protogen:"open.v1"`
 	// @Document Whether this outbound is usable
-	// @Restriction ReadOnlyForUser
+	//@Restriction ReadOnlyForUser
 	Alive bool `protobuf:"varint,1,opt,name=alive,proto3" json:"alive,omitempty"`
 	// @Document The time for probe request to finish.
-	// @Type time.ms
-	// @Restriction ReadOnlyForUser
+	//@Type time.ms
+	//@Restriction ReadOnlyForUser
 	Delay int64 `protobuf:"varint,2,opt,name=delay,proto3" json:"delay,omitempty"`
 	// @Document The error caused this outbound failed to relay probe request
-	// @Restriction NotMachineReadable
+	//@Restriction NotMachineReadable
 	LastErrorReason string `protobuf:"bytes,3,opt,name=last_error_reason,json=lastErrorReason,proto3" json:"last_error_reason,omitempty"`
 	unknownFields   protoimpl.UnknownFields
 	sizeCache       protoimpl.SizeCache
@@ -324,7 +324,7 @@ func (x *ProbeResult) GetLastErrorReason() string {
 type Intensity struct {
 	state protoimpl.MessageState `protogen:"open.v1"`
 	// @Document The time interval for a probe request in ms.
-	// @Type time.ms
+	//@Type time.ms
 	ProbeInterval uint32 `protobuf:"varint,1,opt,name=probe_interval,json=probeInterval,proto3" json:"probe_interval,omitempty"`
 	unknownFields protoimpl.UnknownFields
 	sizeCache     protoimpl.SizeCache

app/router/command/command.proto

@@ -34,18 +34,19 @@ message RoutingContext {
 // opened by xray-core.
 // * FieldSelectors selects a subset of fields in routing statistics to return.
 // Valid selectors:
-//  - inbound: Selects connection's inbound tag.
-//  - network: Selects connection's network.
-//  - ip: Equivalent as "ip_source" and "ip_target", selects both source and
-//  target IP.
-//  - port: Equivalent as "port_source" and "port_target", selects both source
-//  and target port.
-//  - domain: Selects target domain.
-//  - protocol: Select connection's protocol.
-//  - user: Select connection's inbound user email.
-//  - attributes: Select connection's additional attributes.
-//  - outbound: Equivalent as "outbound" and "outbound_group", select both
-//  outbound tag and outbound group tags.
+//   - inbound: Selects connection's inbound tag.
+//   - network: Selects connection's network.
+//   - ip: Equivalent as "ip_source" and "ip_target", selects both source and
+//     target IP.
+//   - port: Equivalent as "port_source" and "port_target", selects both source
+//     and target port.
+//   - domain: Selects target domain.
+//   - protocol: Select connection's protocol.
+//   - user: Select connection's inbound user email.
+//   - attributes: Select connection's additional attributes.
+//   - outbound: Equivalent as "outbound" and "outbound_group", select both
+//     outbound tag and outbound group tags.
+//
 // * If FieldSelectors is left empty, all fields will be returned.
 message SubscribeRoutingStatsRequest {
   repeated string FieldSelectors = 1;

app/router/condition_test.go

@@ -415,7 +415,7 @@ func BenchmarkMphDomainMatcher(b *testing.B) {
 
 func BenchmarkMultiGeoIPMatcher(b *testing.B) {
 	b.Setenv("xray.location.asset", filepath.Join("..", "..", "resources"))
-	rules, err := geodata.ParseIPRules([]string{"geoip:cn", "geoip:jp", "geoip:ca", "geoip:us"})
+	rules, err := geodata.ParseIPRules([]string{"geoip:cn", "geoip:ir", "geoip:ru"})
 	common.Must(err)
 
 	matcher, err := NewIPMatcher(rules, MatcherAsType_Target)

common/geodata/consts.go

@@ -8,23 +8,65 @@ import (
 
 var privateIPMatcher = sync.OnceValue(func() IPMatcher {
 	return common.Must2(IPReg.BuildIPMatcher(common.Must2(ParseIPRules([]string{
-		"0.0.0.0/8",
-		"10.0.0.0/8",
-		"100.64.0.0/10",
-		"127.0.0.0/8",
-		"169.254.0.0/16",
-		"172.16.0.0/12",
-		"192.0.0.0/24",
-		"192.0.2.0/24",
-		"192.88.99.0/24",
-		"192.168.0.0/16",
-		"198.18.0.0/15",
-		"198.51.100.0/24",
-		"203.0.113.0/24",
-		"224.0.0.0/3",
-		"::/127",
-		"fc00::/7",
-		"fe80::/10",
+		// https://www.iana.org/assignments/iana-ipv4-special-registry
+		"0.0.0.0/8",      // "This network"
+		"0.0.0.0/32",     // "This host on this network"
+		"10.0.0.0/8",     // Private-Use
+		"100.64.0.0/10",  // Shared Address Space
+		"127.0.0.0/8",    // Loopback
+		"169.254.0.0/16", // Link Local
+		"172.16.0.0/12",  // Private-Use
+		// "192.0.0.0/24",   // IETF Protocol Assignments
+		"192.0.0.0/29",   // IPv4 Service Continuity Prefix
+		"192.0.0.8/32",   // IPv4 dummy address
+		"192.0.0.9/32",   // Port Control Protocol Anycast
+		"192.0.0.10/32",  // Traversal Using Relays around NAT Anycast
+		"192.0.0.170/32", // NAT64/DNS64 Discovery
+		"192.0.0.171/32", // NAT64/DNS64 Discovery
+		"192.0.2.0/24",   // Documentation (TEST-NET-1)
+		// "192.31.196.0/24",    // AS112-v4
+		"192.52.193.0/24", // AMT
+		// "192.88.99.0/24",  // Deprecated (6to4 Relay Anycast)
+		"192.88.99.2/32", // 6a44-relay anycast address
+		"192.168.0.0/16", // Private-Use
+		// "192.175.48.0/24",    // Direct Delegation AS112 Service
+		"198.18.0.0/15",      // Benchmarking
+		"198.51.100.0/24",    // Documentation (TEST-NET-2)
+		"203.0.113.0/24",     // Documentation (TEST-NET-3)
+		"240.0.0.0/4",        // Reserved
+		"255.255.255.255/32", // Limited Broadcast
+
+		// https://www.iana.org/assignments/multicast-addresses
+		"224.0.0.0/4",
+
+		// https://www.iana.org/assignments/iana-ipv6-special-registry
+		"::1/128", // Loopback Address
+		"::/128",  // Unspecified Address
+		// "::ffff:0:0/96",     // IPv4-mapped Address
+		"64:ff9b::/96",   // IPv4-IPv6 Translat.
+		"64:ff9b:1::/48", // IPv4-IPv6 Translat.
+		"100::/64",       // Discard-Only Address Block
+		"100:0:0:1::/64", // Dummy IPv6 Prefix
+		// "2001::/23",      // IETF Protocol Assignments
+		"2001::/32",     // TEREDO
+		"2001:1::1/128", // Port Control Protocol Anycast
+		"2001:1::2/128", // Traversal Using Relays around NAT Anycast
+		"2001:1::3/128", // DNS-SD Service Registration Protocol Anycast
+		"2001:2::/48",   // Benchmarking
+		"2001:3::/32",   // AMT
+		// "2001:4:112::/48", // AS112-v6
+		// "2001:10::/28",    // Deprecated (previously ORCHID)
+		"2001:20::/28",  // ORCHIDv2
+		"2001:30::/28",  // Drone Remote ID Protocol Entity Tags (DETs) Prefix
+		"2001:db8::/32", // Documentation
+		"2002::/16",     // 6to4
+		// "2620:4f:8000::/48", // Direct Delegation AS112 Service
+		"3fff::/20", // Documentation
+		"5f00::/16", // Segment Routing (SRv6) SIDs
+		"fc00::/7",  // Unique-Local
+		"fe80::/10", // Link-Local Unicast
+
+		// https://www.iana.org/assignments/ipv6-multicast-addresses
 		"ff00::/8",
 	}))))
 })

common/geodata/ip_matcher_test.go

@@ -400,13 +400,13 @@ func TestIPMatcher4CN(t *testing.T) {
 	}
 }
 
-func TestIPMatcher6US(t *testing.T) {
+func TestIPMatcher6RU(t *testing.T) {
 	t.Setenv("xray.location.asset", filepath.Join("..", "..", "resources"))
 
-	matcher := buildIPMatcher("geoip:us")
+	matcher := buildIPMatcher("geoip:ru")
 
-	if !matcher.Match(xnet.ParseAddress("2001:4860:4860::8888").IP()) {
-		t.Error("expect US geoip contain 2001:4860:4860::8888, but actually not")
+	if !matcher.Match(xnet.ParseAddress("2a02:6b8::feed:0ff").IP()) {
+		t.Error("expect RU geoip contain 2a02:6b8::feed:0ff, but actually not")
 	}
 }
 
@@ -423,11 +423,11 @@ func BenchmarkIPMatcher4CN(b *testing.B) {
 	}
 }
 
-func BenchmarkIPMatcher6US(b *testing.B) {
+func BenchmarkIPMatcher6RU(b *testing.B) {
 	b.Setenv("xray.location.asset", filepath.Join("..", "..", "resources"))
 
-	matcher := buildIPMatcher("geoip:us")
-	ip := xnet.ParseAddress("2001:4860:4860::8888").IP()
+	matcher := buildIPMatcher("geoip:ru")
+	ip := xnet.ParseAddress("2a02:6b8::feed:0ff").IP()
 
 	b.ResetTimer()
 

common/geodata/rule_parser_test.go

@@ -11,7 +11,7 @@ func TestParseIPRules(t *testing.T) {
 	t.Setenv("xray.location.asset", filepath.Join("..", "..", "resources"))
 
 	rules := []string{
-		"geoip:us",
+		"geoip:ru",
 		"geoip:cn",
 		"!geoip:cn",
 		"!!geoip:cn",
@@ -20,9 +20,9 @@ func TestParseIPRules(t *testing.T) {
 		"!geoip:!cn",
 		"ext:geoip.dat:!cn",
 		"ext:geoip.dat:!!cn",
-		"ext:geoip.dat:ca",
+		"ext:geoip.dat:ir",
 		"ext-ip:geoip.dat:!cn",
-		"ext-ip:geoip.dat:!ca",
+		"ext-ip:geoip.dat:!ir",
 		"192.168.0.0/24",
 		"!192.168.0.0/24",
 		"!!192.168.0.0/24",

common/lua/program.go

@@ -11,7 +11,7 @@ import (
 
 	"github.com/xtls/xray-core/common/base64"
 	"github.com/xtls/xray-core/common/errors"
-	"github.com/xtls/xray-core/common/platform"
+	"github.com/xtls/xray-core/common/platform/filesystem"
 	glua "github.com/yuin/gopher-lua"
 	"github.com/yuin/gopher-lua/parse"
 )
@@ -36,7 +36,7 @@ func Compile(script string) (*Program, error) {
 		// TODO: Restore inline script support and re-enable the related tests.
 		return nil, errors.New("currently unavailable")
 		code, err = base64.Decode(script)
-	} else if name, err = platform.ResolveLuaFile(script); err == nil {
+	} else if name, err = filesystem.ResolveLuaFile(script); err == nil {
 		code, err = os.ReadFile(name)
 		// TODO: Restore privileged signature authorization and re-enable the related tests and CLI entries.
 		// if err == nil {

common/lua/program_test.go

@@ -187,19 +187,20 @@ func TestCompileInlineDiagnostics(t *testing.T) {
 */
 
 func TestCompileFileExtension(t *testing.T) {
-	for _, name := range []string{"script", "script.dat", "script.lua.txt", "script.LUA"} {
+	for _, name := range []string{"script", "script.dat", "script.lua.txt"} {
+		if program, err := Compile(name); program != nil || err == nil || !strings.Contains(err.Error(), "Lua file extension must be .lua") {
+			t.Fatalf("Compile(%q) = %v, %v; want nil program and .lua extension error", name, program, err)
+		}
+	}
+	for _, name := range []string{"script.lua", "script.LUA", "script.Lua", "script.lUa"} {
 		path := filepath.Join(t.TempDir(), name)
 		if err := os.WriteFile(path, []byte("value = 42"), 0o600); err != nil {
 			t.Fatal(err)
 		}
-		if program, err := Compile(path); program != nil || err == nil || !strings.Contains(err.Error(), "Lua file extension must be .lua") {
-			t.Fatalf("Compile(%q) = %v, %v; want nil program and .lua extension error", path, program, err)
+		if program, err := Compile(path); program == nil || err != nil {
+			t.Fatalf("Compile(%q) = %v, %v; want successful compilation", path, program, err)
 		}
 	}
-	path := writeTestScript(t, "value = 42") + string(filepath.Separator) + "."
-	if program, err := Compile(path); program == nil || err != nil {
-		t.Fatalf("Compile(%q) = %v, %v; want acceptance of the resolved .lua path", path, program, err)
-	}
 }
 
 func TestCompileRejectsReadFailure(t *testing.T) {
@@ -234,10 +235,6 @@ func writeTestScript(t *testing.T, code string) string {
 	if err := os.WriteFile(path, []byte(code), 0o600); err != nil {
 		t.Fatal(err)
 	}
-	path, err := filepath.EvalSymlinks(path)
-	if err != nil {
-		t.Fatal(err)
-	}
 	return path
 }
 

common/net/find_process_linux.go

@@ -4,7 +4,7 @@ package net
 
 import (
 	"bufio"
-	"encoding/hex"
+	"encoding/binary"
 	"fmt"
 	"net"
 	"os"
@@ -26,36 +26,38 @@ func FindProcess(network, srcIP string, srcPort uint16, destIP string, destPort
 		panic("Unsupported network type for process lookup.")
 	}
 
-	var procFile string
+	var procFiles []string
 
 	switch network {
 	case "tcp":
 		if net.ParseIP(srcIP).To4() != nil {
-			procFile = "/proc/net/tcp"
+			procFiles = []string{"/proc/net/tcp"}
 		} else {
-			procFile = "/proc/net/tcp6"
+			procFiles = []string{"/proc/net/tcp6"}
 		}
 	case "udp":
 		if net.ParseIP(srcIP).To4() != nil {
-			procFile = "/proc/net/udp"
+			procFiles = []string{"/proc/net/udp", "/proc/net/udp6"}
 		} else {
-			procFile = "/proc/net/udp6"
+			procFiles = []string{"/proc/net/udp6", "/proc/net/udp"}
 		}
 	default:
 		panic("Unsupported network type for process lookup.")
 	}
 
-	targetHexAddr, err := formatLittleEndianString(net.ParseIP(srcIP), Port(srcPort))
-	if err != nil {
-		return 0, "", "", errors.New("failed to format address: ", err)
+	targetHexAddr := formatProcNetAddress(net.ParseIP(srcIP), Port(srcPort))
+
+	portFallback := ""
+	if network == "udp" {
+		portFallback = fmt.Sprintf(":%04X", srcPort)
 	}
 
-	inode, err := findInodeInFile(procFile, targetHexAddr)
+	inode, err := findInodeInFiles(procFiles, targetHexAddr, portFallback)
 	if err != nil {
-		return 0, "", "", errors.New("could not search in ", procFile).Base(err)
+		return 0, "", "", errors.New("could not search in ", strings.Join(procFiles, " and ")).Base(err)
 	}
 	if inode == "" {
-		return 0, "", "", errors.New("connection for ", srcIP, ":", srcPort, " not found in ", procFile)
+		return 0, "", "", errors.New("connection for ", srcIP, ":", srcPort, " not found in ", strings.Join(procFiles, " or "))
 	}
 
 	pidStr, err := findPidByInode(inode)
@@ -82,51 +84,60 @@ func FindProcess(network, srcIP string, srcPort uint16, destIP string, destPort
 	return pid, procName, absPath, nil
 }
 
-func formatLittleEndianString(addr net.IP, port Port) (string, error) {
-	ip := addr
+func formatProcNetAddress(addr net.IP, port Port) string {
 	var ipBytes []byte
-	if ip.To4() != nil {
-		ipBytes = ip.To4()
+	if ipv4 := addr.To4(); ipv4 != nil {
+		ipBytes = ipv4
 	} else {
-		ipBytes = ip.To16()
-	}
-	if ipBytes == nil {
-		return "", errors.New("invalid IP format for ", addr, ": ", ip)
+		ipBytes = addr.To16()
 	}
 
-	for i, j := 0, len(ipBytes)-1; i < j; i, j = i+1, j-1 {
-		ipBytes[i], ipBytes[j] = ipBytes[j], ipBytes[i]
+	var formatted strings.Builder
+	formatted.Grow(len(ipBytes)*2 + 5)
+	for i := 0; i < len(ipBytes); i += 4 {
+		fmt.Fprintf(&formatted, "%08X", binary.NativeEndian.Uint32(ipBytes[i:i+4]))
 	}
-	portHex := fmt.Sprintf("%04X", uint16(port))
-	ipHex := strings.ToUpper(hex.EncodeToString(ipBytes))
-	return fmt.Sprintf("%s:%s", ipHex, portHex), nil
+	fmt.Fprintf(&formatted, ":%04X", uint16(port))
+	return formatted.String()
 }
 
-func findInodeInFile(filePath, targetHexAddr string) (string, error) {
-	file, err := os.Open(filePath)
-	if err != nil {
-		return "", err
-	}
-	defer file.Close()
+func findInodeInFiles(filePaths []string, targetHexAddr, portFallback string) (string, error) {
+	onlyMatchedPort := ""
 
-	scanner := bufio.NewScanner(file)
-
-	for scanner.Scan() {
-		line := scanner.Text()
-		fields := strings.Fields(line)
-
-		if len(fields) < 10 {
-			continue
+	for i, filePath := range filePaths {
+		file, err := os.Open(filePath)
+		if err != nil {
+			if i > 0 && os.IsNotExist(err) {
+				continue
+			}
+			return "", err
 		}
+		defer file.Close()
 
-		localAddress := fields[1]
-		if localAddress == targetHexAddr {
-			inode := fields[9]
-			return inode, nil
+		scanner := bufio.NewScanner(file)
+		for scanner.Scan() {
+			fields := strings.Fields(scanner.Text())
+			if len(fields) < 10 {
+				continue
+			}
+
+			localAddress := fields[1]
+			if localAddress == targetHexAddr {
+				return fields[9], nil
+			}
+			if portFallback != "" && strings.HasSuffix(localAddress, portFallback) {
+				wildcardIP := strings.TrimSuffix(localAddress, portFallback)
+				if (len(wildcardIP) == 8 || len(wildcardIP) == 32) && strings.Trim(wildcardIP, "0") == "" {
+					onlyMatchedPort = fields[9]
+				}
+			}
+		}
+		if err := scanner.Err(); err != nil {
+			return "", err
 		}
 	}
 
-	return "", scanner.Err()
+	return onlyMatchedPort, nil
 }
 
 func findPidByInode(inode string) (string, error) {

common/platform/filesystem/file.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"github.com/xtls/xray-core/common/buf"
 	"github.com/xtls/xray-core/common/platform"
@@ -26,14 +27,6 @@ func ReadFile(path string) ([]byte, error) {
 	return buf.ReadAllToBytes(reader)
 }
 
-func ReadAsset(file string) ([]byte, error) {
-	path, _, err := getAssetFileLocation(file)
-	if err != nil {
-		return nil, err
-	}
-	return ReadFile(path)
-}
-
 func OpenAsset(file string) (io.ReadCloser, int64, error) {
 	path, info, err := getAssetFileLocation(file)
 	if err != nil {
@@ -43,11 +36,6 @@ func OpenAsset(file string) (io.ReadCloser, int64, error) {
 	return r, info.Size(), err
 }
 
-func StatAsset(file string) (os.FileInfo, error) {
-	_, info, err := getAssetFileLocation(file)
-	return info, err
-}
-
 func ResolveAsset(file string) (string, error) {
 	path, _, err := getAssetFileLocation(file)
 	return path, err
@@ -79,17 +67,29 @@ func ReadCert(file string) ([]byte, error) {
 	return ReadFile(platform.GetCertLocation(file))
 }
 
-func CopyFile(dst string, src string) error {
-	bytes, err := ReadFile(src)
-	if err != nil {
-		return err
+// ResolveLuaFile finds a local .lua script and returns its absolute path.
+// Relative paths: XRAY_LOCATION_CONFDIR > XRAY_LOCATION_CONFIG > working dir > executable dir.
+func ResolveLuaFile(path string) (string, error) {
+	if !strings.EqualFold(filepath.Ext(path), ".lua") {
+		return "", errors.New("Lua file extension must be .lua")
 	}
-	f, err := os.OpenFile(dst, os.O_CREATE|os.O_WRONLY, 0o644)
-	if err != nil {
-		return err
+	if filepath.IsAbs(path) {
+		return path, nil
 	}
-	defer f.Close()
-
-	_, err = f.Write(bytes)
-	return err
+	for _, dir := range []string{
+		platform.GetConfDirPath(),
+		platform.NewEnvFlag(platform.ConfigLocation).GetValue(func() string { return "" }),
+		".",
+		platform.GetExecutableDir(),
+	} {
+		if dir != "" {
+			resolved := filepath.Join(dir, path)
+			if _, err := os.Stat(resolved); err == nil {
+				return filepath.Abs(resolved)
+			} else if !os.IsNotExist(err) {
+				return "", err
+			}
+		}
+	}
+	return "", os.ErrNotExist
 }

common/platform/filesystem/file_test.go

@@ -1,13 +1,17 @@
 package filesystem_test
 
 import (
+	"errors"
+	"os"
 	"path/filepath"
 	"testing"
 
+	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/platform"
 	. "github.com/xtls/xray-core/common/platform/filesystem"
 )
 
-func TestStatAssetRejectsInvalidPath(t *testing.T) {
+func TestResolveAssetRejectsInvalidPath(t *testing.T) {
 	for _, file := range []string{
 		"",
 		".",
@@ -25,8 +29,49 @@ func TestStatAssetRejectsInvalidPath(t *testing.T) {
 		`nested\..\geoip.dat`,
 		filepath.Join(t.TempDir(), "geoip.dat"),
 	} {
-		if _, err := StatAsset(file); err == nil {
+		if _, err := ResolveAsset(file); err == nil {
 			t.Fatalf("expected error for %q", file)
 		}
 	}
 }
+
+func TestResolveLuaFile(t *testing.T) {
+	t.Chdir(t.TempDir())
+	workingDir, err := os.Getwd()
+	common.Must(err)
+	executable, err := os.Executable()
+	common.Must(err)
+	file, err := os.CreateTemp(filepath.Dir(executable), "lua-*.lua")
+	common.Must(err)
+	common.Must(file.Close())
+	defer os.Remove(file.Name())
+
+	name := filepath.Base(file.Name())
+	paths := []string{
+		filepath.Join(t.TempDir(), name),
+		filepath.Join(t.TempDir(), name),
+		filepath.Join(workingDir, name),
+		file.Name(),
+	}
+	t.Setenv(platform.ConfdirLocation, filepath.Dir(paths[0]))
+	t.Setenv(platform.ConfigLocation, filepath.Dir(paths[1]))
+	for _, path := range paths[:3] {
+		common.Must(os.WriteFile(path, nil, 0o600))
+	}
+	if got, err := ResolveLuaFile(paths[2]); err != nil || got != paths[2] {
+		t.Fatalf("absolute path = %q, %v; want %q", got, err, paths[2])
+	}
+	for i, want := range paths {
+		if i == 2 {
+			t.Setenv(platform.ConfdirLocation, "")
+			t.Setenv(platform.ConfigLocation, "")
+		}
+		if got, err := ResolveLuaFile(name); err != nil || got != want {
+			t.Fatalf("resolved path = %q, %v; want %q", got, err, want)
+		}
+		common.Must(os.Remove(want))
+	}
+	if _, err := ResolveLuaFile(name); !errors.Is(err, os.ErrNotExist) {
+		t.Fatalf("missing file error = %v", err)
+	}
+}

common/platform/others.go

@@ -14,7 +14,7 @@ func LineSeparator() string {
 
 // GetAssetLocation searches for `file` in the env dir, the executable dir, and certain locations
 func GetAssetLocation(file string) string {
-	assetPath := NewEnvFlag(AssetLocation).GetValue(getExecutableDir)
+	assetPath := NewEnvFlag(AssetLocation).GetValue(GetExecutableDir)
 	defPath := filepath.Join(assetPath, file)
 	for _, p := range []string{
 		defPath,
@@ -36,6 +36,6 @@ func GetAssetLocation(file string) string {
 
 // GetCertLocation searches for `file` in the env dir and the executable dir
 func GetCertLocation(file string) string {
-	certPath := NewEnvFlag(CertLocation).GetValue(getExecutableDir)
+	certPath := NewEnvFlag(CertLocation).GetValue(GetExecutableDir)
 	return filepath.Join(certPath, file)
 }

common/platform/platform.go

@@ -1,8 +1,6 @@
 package platform // import "github.com/xtls/xray-core/common/platform"
 
 import (
-	"errors"
-	"fmt"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -74,7 +72,7 @@ func NormalizeEnvName(name string) string {
 	return strings.ReplaceAll(strings.ToUpper(strings.TrimSpace(name)), ".", "_")
 }
 
-func getExecutableDir() string {
+func GetExecutableDir() string {
 	exec, err := os.Executable()
 	if err != nil {
 		return ""
@@ -83,7 +81,7 @@ func getExecutableDir() string {
 }
 
 func GetConfigurationPath() string {
-	configPath := NewEnvFlag(ConfigLocation).GetValue(getExecutableDir)
+	configPath := NewEnvFlag(ConfigLocation).GetValue(GetExecutableDir)
 	return filepath.Join(configPath, "config.json")
 }
 
@@ -92,64 +90,3 @@ func GetConfDirPath() string {
 	configPath := NewEnvFlag(ConfdirLocation).GetValue(func() string { return "" })
 	return configPath
 }
-
-// ResolveLuaFile finds a local .lua script and returns its resolved absolute path.
-// Relative paths: XRAY_LOCATION_CONFDIR > XRAY_LOCATION_CONFIG > working dir > executable dir.
-func ResolveLuaFile(path string) (string, error) {
-	if path == "" {
-		return "", errors.New("Lua file path is empty")
-	}
-	paths := []string{path}
-	if !filepath.IsAbs(path) {
-		paths = nil
-		for _, dir := range []string{
-			GetConfDirPath(),
-			NewEnvFlag(ConfigLocation).GetValue(func() string { return "" }),
-			".",
-			getExecutableDir(),
-		} {
-			if dir != "" {
-				paths = append(paths, filepath.Join(dir, path))
-			}
-		}
-	}
-	path, err := resolveFile(paths)
-	if err != nil {
-		return "", err
-	}
-	return resolveLuaTarget(path)
-}
-
-func resolveLuaTarget(path string) (string, error) {
-	path, err := filepath.EvalSymlinks(path)
-	if err != nil {
-		return "", fmt.Errorf("failed to resolve Lua file symlinks: %w", err)
-	}
-	if filepath.Ext(path) != ".lua" {
-		return "", errors.New("Lua file extension must be .lua")
-	}
-	return path, nil
-}
-
-func resolveFile(paths []string) (string, error) {
-	var tried []string
-	for _, path := range paths {
-		path, err := filepath.Abs(path)
-		if err != nil {
-			return "", fmt.Errorf("failed to resolve file path: %w", err)
-		}
-		tried = append(tried, path)
-		info, err := os.Stat(path)
-		if errors.Is(err, os.ErrNotExist) {
-			continue
-		}
-		if err != nil {
-			return "", fmt.Errorf("failed to inspect file %q: %w", path, err)
-		}
-		if !info.Mode().IsRegular() {
-			return "", fmt.Errorf("file is not a regular file: %s", path)
-		}
-		return path, nil
-	}
-	return "", fmt.Errorf("file not found; tried %q: %w", tried, os.ErrNotExist)
-}

common/platform/platform_test.go

@@ -1,11 +1,9 @@
 package platform_test
 
 import (
-	"errors"
 	"os"
 	"path/filepath"
 	"runtime"
-	"strings"
 	"testing"
 
 	"github.com/xtls/xray-core/common"
@@ -66,89 +64,3 @@ func TestGetAssetLocation(t *testing.T) {
 		}
 	}
 }
-
-func TestResolveLuaFile(t *testing.T) {
-	workingDir := t.TempDir()
-	t.Chdir(workingDir)
-	executable, err := os.Executable()
-	common.Must(err)
-	file, err := os.CreateTemp(filepath.Dir(executable), "lua-*.lua")
-	common.Must(err)
-	common.Must(file.Close())
-	defer os.Remove(file.Name())
-
-	name := filepath.Base(file.Name())
-	paths := []string{
-		filepath.Join(t.TempDir(), name),
-		filepath.Join(t.TempDir(), name),
-		filepath.Join(workingDir, name),
-		file.Name(),
-	}
-	t.Setenv(ConfdirLocation, filepath.Dir(paths[0]))
-	t.Setenv(ConfigLocation, filepath.Dir(paths[1]))
-	for _, path := range paths[:3] {
-		common.Must(os.WriteFile(path, nil, 0o600))
-	}
-	for i, path := range paths {
-		paths[i], err = filepath.EvalSymlinks(path)
-		common.Must(err)
-	}
-	if got, err := ResolveLuaFile(paths[2]); err != nil || got != paths[2] {
-		t.Fatalf("absolute path = %q, %v; want %q", got, err, paths[2])
-	}
-	for i, want := range paths {
-		if i == 2 {
-			t.Setenv(ConfdirLocation, "")
-			t.Setenv(ConfigLocation, "")
-		}
-		if got, err := ResolveLuaFile(name); err != nil || got != want {
-			t.Fatalf("resolved path = %q, %v; want %q", got, err, want)
-		}
-		common.Must(os.Remove(want))
-	}
-	if _, err := ResolveLuaFile(name); !errors.Is(err, os.ErrNotExist) {
-		t.Fatalf("missing file error = %v", err)
-	}
-
-	t.Setenv(ConfdirLocation, filepath.Dir(paths[0]))
-	t.Setenv(ConfigLocation, filepath.Dir(paths[1]))
-	common.Must(os.Mkdir(paths[0], 0o700))
-	common.Must(os.WriteFile(paths[1], nil, 0o600))
-	for _, path := range []string{"", name, filepath.Join(t.TempDir(), name)} {
-		if _, err := ResolveLuaFile(path); err == nil {
-			t.Fatalf("accepted invalid path %q", path)
-		}
-	}
-}
-
-func TestResolveLuaFileSymlink(t *testing.T) {
-	for _, tc := range []struct {
-		link, target string
-		valid        bool
-	}{
-		{"alias.lua", "data.dat", false},
-		{"alias.dat", "script.lua", true},
-	} {
-		t.Run(tc.link, func(t *testing.T) {
-			dir, err := filepath.EvalSymlinks(t.TempDir())
-			common.Must(err)
-			target := filepath.Join(dir, tc.target)
-			common.Must(os.WriteFile(target, nil, 0o600))
-			link := filepath.Join(dir, tc.link)
-			if err := os.Symlink(tc.target, link); err != nil {
-				if runtime.GOOS == "windows" {
-					t.Skipf("cannot create symlinks: %v", err)
-				}
-				t.Fatal(err)
-			}
-			got, err := ResolveLuaFile(link)
-			if tc.valid {
-				if err != nil || got != target {
-					t.Fatalf("ResolveLuaFile(%q) = %q, %v; want %q", link, got, err, target)
-				}
-			} else if err == nil || got != "" || !strings.Contains(err.Error(), "Lua file extension must be .lua") {
-				t.Fatalf("ResolveLuaFile(%q) = %q, %v; want .lua extension error", link, got, err)
-			}
-		})
-	}
-}

common/platform/windows.go

@@ -11,12 +11,12 @@ func LineSeparator() string {
 
 // GetAssetLocation searches for `file` in the env dir and the executable dir
 func GetAssetLocation(file string) string {
-	assetPath := NewEnvFlag(AssetLocation).GetValue(getExecutableDir)
+	assetPath := NewEnvFlag(AssetLocation).GetValue(GetExecutableDir)
 	return filepath.Join(assetPath, file)
 }
 
 // GetCertLocation searches for `file` in the env dir and the executable dir
 func GetCertLocation(file string) string {
-	certPath := NewEnvFlag(CertLocation).GetValue(getExecutableDir)
+	certPath := NewEnvFlag(CertLocation).GetValue(GetExecutableDir)
 	return filepath.Join(certPath, file)
 }

core/core.go

@@ -20,7 +20,7 @@ import (
 var (
 	Version_x byte = 26
 	Version_y byte = 10
-	Version_z byte = 17
+	Version_z byte = 29
 )
 
 var (

core/proto.go

@@ -1,5 +1,3 @@
 package core
 
-//go:generate go install -v google.golang.org/protobuf/cmd/protoc-gen-go@latest
-//go:generate go install -v google.golang.org/grpc/cmd/protoc-gen-go-grpc@latest
 //go:generate go run ../infra/vprotogen/main.go -pwd ./..

features/dns/localdns/client.go

@@ -2,6 +2,7 @@ package localdns
 
 import (
 	"context"
+	"net/netip"
 	"syscall"
 	"time"
 
@@ -100,6 +101,15 @@ func New() *Client {
 			if internet.IsSkippedDNSServer(address) {
 				return nil, errors.New("skipped DNS server ", address)
 			}
+			// A socket of the server's IP version only needs that version bound
+			// to the interface, which a dual-stack one would need both of.
+			if ap, err := netip.ParseAddrPort(address); err == nil && (network == "udp" || network == "tcp") {
+				if ap.Addr().Unmap().Is4() {
+					network += "4"
+				} else {
+					network += "6"
+				}
+			}
 			return d.DialContext(ctx, network, address)
 		},
 	}

go.mod

@@ -4,17 +4,18 @@ go 1.27
 
 require (
 	github.com/apernet/quic-go v0.61.1-0.20260806010916-184d081eef3e
+	github.com/bufbuild/protocompile v0.14.1
 	github.com/ghodss/yaml v1.0.1-0.20220118164431-d8423dcdf344
 	github.com/golang/mock v1.7.0-rc.1
 	github.com/google/go-cmp v0.7.0
 	github.com/google/uuid v1.6.0
 	github.com/gorilla/websocket v1.5.3
-	github.com/klauspost/cpuid/v2 v2.4.0
+	github.com/klauspost/cpuid/v2 v2.4.1
 	github.com/libp2p/go-nat v1.0.1-0.20250821073202-01afc089f138
 	github.com/miekg/dns v1.1.73
 	github.com/pelletier/go-toml v1.9.5
 	github.com/pion/stun/v3 v3.1.7
-	github.com/pires/go-proxyproto v0.15.0
+	github.com/pires/go-proxyproto v0.16.0
 	github.com/refraction-networking/utls v1.8.3-0.20260301010127-aa6edf4b11af
 	github.com/robfig/cron/v3 v3.0.1
 	github.com/stretchr/testify v1.12.1
@@ -23,7 +24,7 @@ require (
 	github.com/yuin/gopher-lua v1.1.2
 	go4.org/netipx v0.0.0-20231129151722-fdeea329fbba
 	golang.org/x/crypto v0.58.0
-	golang.org/x/crypto/x509roots/fallback v0.0.0-20261005185213-c3db4df58582
+	golang.org/x/crypto/x509roots/fallback v0.0.0-20261020153306-9f2b28d4331a
 	golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842
 	golang.org/x/net v0.61.0
 	golang.org/x/sync v0.24.0
@@ -32,7 +33,7 @@ require (
 	golang.zx2c4.com/wireguard v0.0.0-20250521234502-f333402bd9cb
 	golang.zx2c4.com/wireguard/windows v1.1.1
 	google.golang.org/grpc v1.84.0
-	google.golang.org/protobuf v1.36.12
+	google.golang.org/protobuf v1.36.11
 	h12.io/socks v1.0.3
 	layeh.com/gopher-luar v1.0.11
 	lukechampine.com/blake3 v1.4.1
@@ -58,6 +59,12 @@ require (
 	golang.org/x/text v0.43.0 // indirect
 	golang.org/x/tools v0.51.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20260706201446-f0a921348800 // indirect
+	google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.6.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 	gvisor.dev/gvisor v0.0.0-20260122175437-89a5d21be8f0 // indirect
 )
+
+tool (
+	google.golang.org/grpc/cmd/protoc-gen-go-grpc
+	google.golang.org/protobuf/cmd/protoc-gen-go
+)

go.sum

@@ -2,6 +2,8 @@ github.com/andybalholm/brotli v1.2.3 h1:8H1qwOkl2LPfjf3YezB90JnCliZb6SInJ/OJkEbA
 github.com/andybalholm/brotli v1.2.3/go.mod h1:rzTDkvFWvIrjDXZHkuS16NPggd91W3kUSvPlQ1pLaKY=
 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/bufbuild/protocompile v0.14.1 h1:iA73zAf/fyljNjQKwYzUHD6AD4R8KMasmwa/FBatYVw=
+github.com/bufbuild/protocompile v0.14.1/go.mod h1:ppVdAIhbr2H8asPk6k4pY7t9zB1OU5DoEw9xY/FUi1c=
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
 github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
@@ -33,8 +35,8 @@ github.com/juju/ratelimit v1.0.2 h1:sRxmtRiajbvrcLQT7S+JbqU0ntsb9W2yhSdNN8tWfaI=
 github.com/juju/ratelimit v1.0.2/go.mod h1:qapgC/Gy+xNh9UxzV13HGGl/6UXNN+ct+vwSgWNm/qk=
 github.com/klauspost/compress v1.20.0 h1:a3C1ke2ohxFymNlb2HWAHjDeKCI90scRskErZkR0ezA=
 github.com/klauspost/compress v1.20.0/go.mod h1:LUdAzn7YLVvxLpc7y3V1m40wESHTgc1422pwwBSKYuI=
-github.com/klauspost/cpuid/v2 v2.4.0 h1:S6Hrbc7+ywsr0r+RLapfGBHfyefhCTwEh3A0tV913Dw=
-github.com/klauspost/cpuid/v2 v2.4.0/go.mod h1:19jmZ9mjzoF//ddRSUsv0zfBTJWh3QJh9FNxZTMrGxU=
+github.com/klauspost/cpuid/v2 v2.4.1 h1:I9KxadAkvo+QjtcEE2f2tyfEvmIla/T0m+14PrZNl0U=
+github.com/klauspost/cpuid/v2 v2.4.1/go.mod h1:19jmZ9mjzoF//ddRSUsv0zfBTJWh3QJh9FNxZTMrGxU=
 github.com/koron/go-ssdp v0.0.4 h1:1IDwrghSKYM7yLf7XCzbByg2sJ/JcNOZRXS2jczTwz0=
 github.com/koron/go-ssdp v0.0.4/go.mod h1:oDXq+E5IL5q0U8uSBcoAXzTzInwy5lEgC91HoKtbmZk=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
@@ -59,8 +61,8 @@ github.com/pion/stun/v3 v3.1.7 h1:uRXMTlGLf89WgItGNyZ6aR5jMTX0NBbybXADpQCzn+E=
 github.com/pion/stun/v3 v3.1.7/go.mod h1:Nq77RW4aRrSNrltf2ksUJLjxWeipj4lnlgdsYIxC8g8=
 github.com/pion/transport/v4 v4.1.0 h1:8S+nF2reM2cJuqC6g78OVy2BBgmbdns+acx3jA97BvQ=
 github.com/pion/transport/v4 v4.1.0/go.mod h1:06hFI+jCFcok2X2MekVufNZ/uzNZXivGBPfviSVcjgM=
-github.com/pires/go-proxyproto v0.15.0 h1:dTshmNbFm/D+0+sbrxUuddPOZ5Y0B7c5NhtsBkm6LqI=
-github.com/pires/go-proxyproto v0.15.0/go.mod h1:OXsCrKwrK2tXS9YrI5tkHx5xaQlO8FH3lFW76orFh24=
+github.com/pires/go-proxyproto v0.16.0 h1:9KYT/fM3wpjT8bdMEj/7FBcoiUG1KyzEjRYnPu+vz7A=
+github.com/pires/go-proxyproto v0.16.0/go.mod h1:n7yhg8yIfNl3KgYDCwBzmeUHNpKTVnUhcWpc7rV4RW4=
 github.com/quic-go/go-ossfuzz-seeds v0.1.0 h1:APacT+iIaNF6fd8AGEiN3bT/Jtkd2jz4v4TzM7MFjy0=
 github.com/quic-go/go-ossfuzz-seeds v0.1.0/go.mod h1:3IOHRbJIc+L6YKMwfDtJAM9Vj9k0YY4muhuyUYk5tbk=
 github.com/quic-go/qpack v0.6.0 h1:g7W+BMYynC1LbYLSqRt8PBg5Tgwxn214ZZR34VIOjz8=
@@ -97,8 +99,8 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACk
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.58.0 h1:COkYLr4k7nDI4r6QtMML2AfzeIswWHAJthLS6K/M/54=
 golang.org/x/crypto v0.58.0/go.mod h1:Xh+kl5A+M0gMiWDytH2Hhr5Z7WbNCpv/eB/EFgfSk+w=
-golang.org/x/crypto/x509roots/fallback v0.0.0-20261005185213-c3db4df58582 h1:wjDBrGbfLuifgrVLFEWUBJYAfh5Q1wkMc5t0FY0tCbs=
-golang.org/x/crypto/x509roots/fallback v0.0.0-20261005185213-c3db4df58582/go.mod h1:HPze8vhfG6fO06AM+VSvxRm4E3+5Yk375mgrJ5M2z1E=
+golang.org/x/crypto/x509roots/fallback v0.0.0-20261020153306-9f2b28d4331a h1:V5oicZXS0oqZx30gY/apgSVD7YvNBfrIOdcMnlelJY4=
+golang.org/x/crypto/x509roots/fallback v0.0.0-20261020153306-9f2b28d4331a/go.mod h1:HPze8vhfG6fO06AM+VSvxRm4E3+5Yk375mgrJ5M2z1E=
 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=
@@ -152,6 +154,10 @@ google.golang.org/genproto/googleapis/rpc v0.0.0-20260706201446-f0a921348800 h1:
 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/grpc/cmd/protoc-gen-go-grpc v1.6.0 h1:6Al3kEFFP9VJhRz3DID6quisgPnTeZVr4lep9kkxdPA=
+google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.6.0/go.mod h1:QLvsjh0OIR0TYBeiu2bkWGTJBUNQ64st52iWj/yA93I=
+google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
+google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
 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=

infra/conf/freedom.go

@@ -91,6 +91,7 @@ func (c *FreedomConfig) Build() (proto.Message, error) {
 	}
 
 	if c.Fragment != nil {
+		errors.PrintDeprecatedFeatureWarning(`"fragment" in Freedom`, `"fragment" in "streamSettings.finalmask.tcp"`)
 		config.Fragment = new(freedom.Fragment)
 
 		switch strings.ToLower(c.Fragment.Packets) {
@@ -147,6 +148,7 @@ func (c *FreedomConfig) Build() (proto.Message, error) {
 	}
 
 	if c.Noises != nil {
+		errors.PrintDeprecatedFeatureWarning(`"noises" in Freedom`, `"noise" in "streamSettings.finalmask.udp"`)
 		for _, n := range c.Noises {
 			NConfig, err := ParseNoise(n)
 			if err != nil {

infra/conf/geodata.go

@@ -6,7 +6,6 @@ import (
 	"github.com/robfig/cron/v3"
 	"github.com/xtls/xray-core/app/geodata"
 	"github.com/xtls/xray-core/common/errors"
-	"github.com/xtls/xray-core/common/platform/filesystem"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -19,9 +18,6 @@ func (c *GeodataAssetConfig) Build() (*geodata.Asset, error) {
 	if err := validateHTTPS(c.URL); err != nil {
 		return nil, errors.New("invalid geodata asset url: ", c.URL).Base(err)
 	}
-	if _, err := filesystem.StatAsset(c.File); err != nil {
-		return nil, errors.New("invalid geodata asset file: ", c.File).Base(err)
-	}
 	return &geodata.Asset{
 		Url:  c.URL,
 		File: c.File,

infra/conf/geodata_test.go

@@ -1,7 +1,6 @@
 package conf_test
 
 import (
-	"path/filepath"
 	"testing"
 
 	"github.com/xtls/xray-core/app/geodata"
@@ -9,8 +8,6 @@ import (
 )
 
 func TestGeodataConfig(t *testing.T) {
-	t.Setenv("xray.location.asset", filepath.Join("..", "..", "resources"))
-
 	creator := func() Buildable {
 		return new(GeodataConfig)
 	}
@@ -38,27 +35,7 @@ func TestGeodataConfig(t *testing.T) {
 	})
 }
 
-func TestGeodataAssetConfig(t *testing.T) {
-	t.Setenv("xray.location.asset", filepath.Join("..", "..", "resources"))
-
-	if _, err := (&GeodataAssetConfig{
-		URL:  "https://example.com/geoip.dat",
-		File: "geoip.dat",
-	}).Build(); err != nil {
-		t.Fatal(err)
-	}
-
-	if _, err := (&GeodataAssetConfig{
-		URL:  "https://example.com/geoip.dat",
-		File: "missing.dat",
-	}).Build(); err == nil {
-		t.Fatal("expected error")
-	}
-}
-
 func TestGeodataAssetConfigInvalidURL(t *testing.T) {
-	t.Setenv("xray.location.asset", filepath.Join("..", "..", "resources"))
-
 	for _, rawURL := range []string{
 		"",
 		"http://example.com/geoip.dat",

infra/conf/transport_finalmask.go

@@ -15,9 +15,11 @@ import (
 
 	googleuuid "github.com/google/uuid"
 	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/geodata"
 	xlua "github.com/xtls/xray-core/common/lua"
 	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/finalmask/filter"
 	"github.com/xtls/xray-core/transport/internet/finalmask/fragment"
 	"github.com/xtls/xray-core/transport/internet/finalmask/header/custom"
 	"github.com/xtls/xray-core/transport/internet/finalmask/mkcp/aes128gcm"
@@ -74,6 +76,7 @@ var (
 	customVarNamePattern = regexp.MustCompile(`^[A-Za-z_][A-Za-z0-9_]*$`)
 
 	tcpmaskLoader = NewJSONConfigLoader(ConfigCreatorCache{
+		"filter":        func() interface{} { return new(Filter) },
 		"header-custom": func() interface{} { return new(HeaderCustomTCP) },
 		"fragment":      func() interface{} { return new(FragmentMask) },
 		"sudoku":        func() interface{} { return new(Sudoku) },
@@ -81,6 +84,7 @@ var (
 	}, "type", "settings")
 
 	udpmaskLoader = NewJSONConfigLoader(ConfigCreatorCache{
+		"filter":        func() interface{} { return new(Filter) },
 		"header-custom": func() interface{} { return new(HeaderCustomUDP) },
 		"mkcp-legacy":   func() interface{} { return new(MkcpLegacy) },
 		"noise":         func() interface{} { return new(NoiseMask) },
@@ -93,6 +97,23 @@ var (
 	}, "type", "settings")
 )
 
+type Filter struct {
+	BlockedSourceIPs []string `json:"blockedSourceIPs"`
+	AllowedSourceIPs []string `json:"allowedSourceIPs"`
+}
+
+func (c *Filter) Build() (proto.Message, error) {
+	rules, err := geodata.ParseIPRules(c.BlockedSourceIPs)
+	if err != nil {
+		return nil, errors.New(`invalid "blockedSourceIPs"`).Base(err)
+	}
+	allowed, err := geodata.ParseIPRules(c.AllowedSourceIPs)
+	if err != nil {
+		return nil, errors.New(`invalid "allowedSourceIPs"`).Base(err)
+	}
+	return &filter.Config{BlockedSourceIps: rules, AllowedSourceIps: allowed}, nil
+}
+
 type TCPItem struct {
 	Delay     Int32Range       `json:"delay"`
 	Rand      int32            `json:"rand"`

infra/conf/transport_finalmask_filter_test.go

@@ -0,0 +1,79 @@
+package conf_test
+
+import (
+	"encoding/json"
+	"fmt"
+	"net"
+	"strings"
+	"testing"
+
+	"github.com/xtls/xray-core/common/geodata"
+	. "github.com/xtls/xray-core/infra/conf"
+	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/finalmask/filter"
+)
+
+func TestFinalMaskFilter(t *testing.T) {
+	for _, network := range []string{"tcp", "udp"} {
+		for _, test := range []struct {
+			name, settings   string
+			blocked, allowed int
+		}{
+			{"blacklist", `{"blockedSourceIPs":["192.0.2.0/24"]}`, 1, 0},
+			{"whitelist", `{"allowedSourceIPs":["192.0.2.0/24"]}`, 0, 1},
+			{"both", `{"blockedSourceIPs":["192.0.2.0/24"],"allowedSourceIPs":["192.0.2.0/24"]}`, 1, 1},
+			{"empty_whitelist", `{"allowedSourceIPs":[]}`, 0, 0},
+			{"empty_blacklist", `{"blockedSourceIPs":[]}`, 0, 0},
+		} {
+			t.Run(network+"/"+test.name, func(t *testing.T) {
+				input := fmt.Sprintf(`{"finalmask":{"%s":[{"type":"filter","settings":%s}]}}`, network, test.settings)
+				var config StreamConfig
+				if err := json.Unmarshal([]byte(input), &config); err != nil {
+					t.Fatal(err)
+				}
+				built, err := config.Build()
+				if err != nil {
+					t.Fatal(err)
+				}
+				masks := built.Tcpmasks
+				if network == "udp" {
+					masks = built.Udpmasks
+				}
+				if len(masks) != 1 {
+					t.Fatalf("expected one mask, got %d", len(masks))
+				}
+				instance, err := masks[0].GetInstance()
+				if err != nil {
+					t.Fatal(err)
+				}
+				filter, ok := instance.(*filter.Config)
+				if !ok {
+					t.Fatalf("unexpected mask type: %T", instance)
+				}
+				if len(filter.BlockedSourceIps) != test.blocked || len(filter.AllowedSourceIps) != test.allowed {
+					t.Fatalf("unexpected filter policy: %v", filter)
+				}
+				for _, rules := range [][]*geodata.IPRule{filter.BlockedSourceIps, filter.AllowedSourceIps} {
+					for _, rule := range rules {
+						cidr := rule.GetCustom().GetCidr()
+						if cidr.GetPrefix() != 24 || !net.IP(cidr.GetIp()).Equal(net.IPv4(192, 0, 2, 0)) {
+							t.Fatalf("unexpected IP rule: %v", cidr)
+						}
+					}
+				}
+				if _, err := internet.ToMemoryStreamConfig(built); err != nil {
+					t.Fatalf("failed to initialize runtime finalmask: %v", err)
+				}
+			})
+		}
+	}
+	for _, field := range []string{"blockedSourceIPs", "allowedSourceIPs"} {
+		var config Filter
+		if err := json.Unmarshal([]byte(fmt.Sprintf(`{"%s":["192.0.2.0/33"]}`, field)), &config); err != nil {
+			t.Fatal(err)
+		}
+		if _, err := config.Build(); err == nil || !strings.Contains(err.Error(), field) {
+			t.Errorf("expected invalid %s, got %v", field, err)
+		}
+	}
+}

infra/conf/transport_internet.go

@@ -90,6 +90,7 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 		config.ProtocolName = protocol
 	}
 
+	var xdriveH3 bool
 	switch strings.ToLower(c.Security) {
 	case "", "none":
 	case "tls":
@@ -104,6 +105,7 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 		tm := serial.ToTypedMessage(ts)
 		config.SecuritySettings = append(config.SecuritySettings, tm)
 		config.SecurityType = tm.Type
+		xdriveH3 = config.ProtocolName == "xdrive" && tlsSettings.ALPN != nil && slices.Equal(*tlsSettings.ALPN, StringList{"h3"})
 		if config.ProtocolName == "xdrive" && tlsSettings.ALPN != nil && slices.Equal(*tlsSettings.ALPN, StringList{"http/1.1"}) && tlsSettings.ECHConfigList == "" {
 			// a fingerprint puts its own ALPN into the hello, except Go TLS and the
 			// randomized ones, which take it from the config or send none
@@ -219,6 +221,7 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 		})
 	}
 	if c.XDRIVESettings != nil {
+		c.XDRIVESettings.h3 = xdriveH3
 		xs, err := c.XDRIVESettings.Build()
 		if err != nil {
 			return nil, errors.New("Failed to build XDRIVE config.").Base(err)
@@ -260,5 +263,20 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 		}
 	}
 
+	if xdriveH3 && c.FinalMask != nil {
+		if c.XDRIVESettings != nil && c.XDRIVESettings.Service == "google-drive" {
+			// noise only sends datagrams of its own ahead of the QUIC ones, the
+			// other masks change those or need a peer that undoes them
+			for _, mask := range c.FinalMask.Udp {
+				if strings.ToLower(mask.Type) != "noise" {
+					return nil, errors.New(`XDRIVE: over h3 to Google Drive the only "udp" mask that works is "noise", not "`, mask.Type, `"`)
+				}
+			}
+		}
+		if config.QuicParams != nil && (config.QuicParams.Congestion == "brutal" || config.QuicParams.Congestion == "force-brutal") {
+			return nil, errors.New(`XDRIVE: brutal is for Hysteria servers, over h3 "congestion" is "bbr" or "reno", not "`, config.QuicParams.Congestion, `"`)
+		}
+	}
+
 	return config, nil
 }

infra/conf/transport_method.go

@@ -997,6 +997,18 @@ type XDriveConfig struct {
 	EagerWindowMs     uint32          `json:"eagerWindowMs"`
 	HoleTimeoutMs     uint32          `json:"holeTimeoutMs"`
 	Template          json.RawMessage `json:"template"`
+	S3                *XDriveS3Config `json:"s3"`
+	Xmux              XmuxConfig      `json:"xmux"`
+
+	// set by StreamConfig when "alpn" is ["h3"]
+	h3 bool
+}
+
+type XDriveS3Config struct {
+	Endpoint  string `json:"endpoint"`
+	Region    string `json:"region"`
+	Bucket    string `json:"bucket"`
+	PathStyle *bool  `json:"pathStyle"`
 }
 
 // Build implements Buildable.
@@ -1015,8 +1027,27 @@ func (c *XDriveConfig) Build() (proto.Message, error) {
 		if len(c.Template) == 0 {
 			return nil, errors.New(`service "template" needs a "template" object`)
 		}
+	case "s3":
+		if c.S3 == nil {
+			return nil, errors.New(`service "s3" needs an "s3" object`)
+		}
 	default:
-		return nil, errors.New(`unknown "service": "`, c.Service, `", use "google-drive", "template" or "local"`)
+		return nil, errors.New(`unknown "service": "`, c.Service, `", use "google-drive", "template", "s3" or "local"`)
+	}
+	if c.Xmux.MaxConnections.To > 0 && c.Xmux.MaxConcurrency.To > 0 {
+		return nil, errors.New("maxConnections cannot be specified together with maxConcurrency")
+	}
+	if c.Xmux == (XmuxConfig{}) {
+		c.Xmux.MaxConnections.From = 1
+		c.Xmux.MaxConnections.To = 1
+		if c.Service == "google-drive" && !c.h3 {
+			// Google gives an h2 connection 1 MiB of window, which a few sessions on
+			// a long rtt would share, an h3 connection has no such limit
+			c.Xmux.MaxConnections.From = 4
+			c.Xmux.MaxConnections.To = 4
+		}
+		c.Xmux.HMaxReusableSecs.From = 1800
+		c.Xmux.HMaxReusableSecs.To = 3000
 	}
 	config := &xdrive.Config{
 		RemoteFolder:      c.RemoteFolder,
@@ -1031,6 +1062,25 @@ func (c *XDriveConfig) Build() (proto.Message, error) {
 		EagerWindowMs:     c.EagerWindowMs,
 		HoleTimeoutMs:     c.HoleTimeoutMs,
 		Template:          string(c.Template),
+		Xmux: &splithttp.XmuxConfig{
+			MaxConcurrency:   newRangeConfig(c.Xmux.MaxConcurrency),
+			MaxConnections:   newRangeConfig(c.Xmux.MaxConnections),
+			CMaxReuseTimes:   newRangeConfig(c.Xmux.CMaxReuseTimes),
+			HMaxRequestTimes: newRangeConfig(c.Xmux.HMaxRequestTimes),
+			HMaxReusableSecs: newRangeConfig(c.Xmux.HMaxReusableSecs),
+			HKeepAlivePeriod: c.Xmux.HKeepAlivePeriod,
+		},
+	}
+	if c.Service == "s3" {
+		config.S3 = &xdrive.S3Config{
+			Endpoint:  c.S3.Endpoint,
+			Region:    c.S3.Region,
+			Bucket:    c.S3.Bucket,
+			PathStyle: c.S3.PathStyle == nil || *c.S3.PathStyle,
+		}
+		if err := xdrive.ValidateS3Config(config); err != nil {
+			return nil, err
+		}
 	}
 	return config, nil
 }

infra/conf/transport_test.go

@@ -9,6 +9,7 @@ import (
 	. "github.com/xtls/xray-core/infra/conf"
 	"github.com/xtls/xray-core/transport/internet"
 	finalmaskcustom "github.com/xtls/xray-core/transport/internet/finalmask/header/custom"
+	"github.com/xtls/xray-core/transport/internet/splithttp"
 	"github.com/xtls/xray-core/transport/internet/xdrive"
 	"google.golang.org/protobuf/proto"
 )
@@ -323,7 +324,7 @@ func TestXDriveRejectsUnknownService(t *testing.T) {
 	if err := json.Unmarshal([]byte(`{"remoteFolder": "/tmp/xdrive", "service": "Dropbox"}`), config); err != nil {
 		t.Fatalf("Unmarshal: %v", err)
 	}
-	if _, err := config.Build(); err == nil || !strings.Contains(err.Error(), `use "google-drive", "template" or "local"`) {
+	if _, err := config.Build(); err == nil || !strings.Contains(err.Error(), `use "google-drive", "template", "s3" or "local"`) {
 		t.Fatalf("expected an unknown service error, got %v", err)
 	}
 }
@@ -424,6 +425,81 @@ func TestXDriveHTTP1ALPNWarning(t *testing.T) {
 	}
 }
 
+// over h3 Google Drive takes only the noise mask, and no service takes brutal
+func TestXDriveH3Checks(t *testing.T) {
+	const (
+		drive       = `"method": "xdrive", "xdriveSettings": {"remoteFolder": "f", "service": "google-drive", "secrets": ["a", "b", "c"]}`
+		local       = `"method": "xdrive", "xdriveSettings": {"remoteFolder": "/tmp/xdrive", "service": "local"}`
+		noise       = `{"type": "Noise", "settings": {"noise": [{"rand": "50-100"}]}}`
+		salamander  = `{"type": "salamander", "settings": {"password": "p"}}`
+		forceBrutal = `{"quicParams": {"congestion": "force-brutal", "brutalUp": "10 mbps"}}`
+	)
+	for _, c := range []struct {
+		alpn, transport, finalmask string
+		ok                         bool
+	}{
+		{`["h3"]`, drive, `{"udp": [` + noise + `]}`, true},
+		{`["h3"]`, drive, `{"udp": [` + salamander + `]}`, false},
+		{`["h3"]`, drive, `{"udp": [` + noise + `, ` + salamander + `]}`, false},
+		{`["h3"]`, local, `{"udp": [` + salamander + `]}`, true},
+		{`["h3"]`, `"method": "xdrive"`, `{"udp": [` + salamander + `]}`, true},
+		{`["h2"]`, drive, `{"udp": [` + salamander + `]}`, true},
+		{`null`, drive, `{"udp": [` + salamander + `]}`, true},
+		{`["h3"]`, drive, `null`, true},
+		{`["h3"]`, drive, `{"quicParams": {"congestion": "bbr"}}`, true},
+		{`["h3"]`, drive, `{"quicParams": {"congestion": "brutal"}}`, false},
+		{`["h3"]`, local, forceBrutal, false},
+		{`["h3", "h2"]`, drive, `{"quicParams": {"congestion": "brutal"}}`, true},
+		{`["h3"]`, `"method": "xhttp"`, forceBrutal, true},
+	} {
+		config := new(StreamConfig)
+		if err := json.Unmarshal([]byte(`{
+			`+c.transport+`,
+			"security": "tls",
+			"tlsSettings": {"alpn": `+c.alpn+`},
+			"finalmask": `+c.finalmask+`
+		}`), config); err != nil {
+			t.Fatalf("Unmarshal: %v", err)
+		}
+		if _, err := config.Build(); (err == nil) != c.ok {
+			t.Errorf("alpn %s, %s, finalmask %s: %v", c.alpn, c.transport, c.finalmask, err)
+		}
+	}
+}
+
+// one h3 connection is not held back by a window like h2, so h3 takes one by default
+func TestXDriveH3Connections(t *testing.T) {
+	for _, c := range []struct {
+		alpn string
+		want int32
+	}{
+		{`["h3"]`, 1},
+		{`["h2"]`, 4},
+		{`null`, 4},
+	} {
+		config := new(StreamConfig)
+		if err := json.Unmarshal([]byte(`{
+			"method": "xdrive",
+			"xdriveSettings": {"remoteFolder": "f", "service": "google-drive", "secrets": ["a", "b", "c"]},
+			"security": "tls",
+			"tlsSettings": {"alpn": `+c.alpn+`}
+		}`), config); err != nil {
+			t.Fatalf("Unmarshal: %v", err)
+		}
+		built, err := config.Build()
+		if err != nil {
+			t.Fatalf("alpn %s: %v", c.alpn, err)
+		}
+		xs, err := built.TransportSettings[0].Settings.GetInstance()
+		if err != nil {
+			t.Fatalf("alpn %s: %v", c.alpn, err)
+		}
+		if got := xs.(*xdrive.Config).Xmux.MaxConnections; got.From != c.want || got.To != c.want {
+			t.Errorf("alpn %s: maxConnections is %d-%d, want %d", c.alpn, got.From, got.To, c.want)
+		}
+	}
+}
+
 func TestXDriveTemplateNeedsTemplate(t *testing.T) {
 	config := new(XDriveConfig)
 	if err := json.Unmarshal([]byte(`{"remoteFolder": "f", "service": "template"}`), config); err != nil {
@@ -513,3 +589,50 @@ func TestXDriveInboundConfig(t *testing.T) {
 		}
 	}
 }
+
+func TestXDriveXmux(t *testing.T) {
+	defaults := func(connections int32) *splithttp.XmuxConfig {
+		return &splithttp.XmuxConfig{
+			MaxConcurrency:   &splithttp.RangeConfig{},
+			MaxConnections:   &splithttp.RangeConfig{From: connections, To: connections},
+			CMaxReuseTimes:   &splithttp.RangeConfig{},
+			HMaxRequestTimes: &splithttp.RangeConfig{},
+			HMaxReusableSecs: &splithttp.RangeConfig{From: 1800, To: 3000},
+		}
+	}
+	for _, c := range []struct {
+		input string
+		want  *splithttp.XmuxConfig
+	}{
+		{`{"service": "google-drive", "secrets": ["a", "b", "c"]}`, defaults(4)},
+		{`{"service": "template", "template": {}}`, defaults(1)},
+		{`{"service": "google-drive", "secrets": ["a", "b", "c"], "xmux": {"maxConcurrency": "1-2", "hMaxRequestTimes": 100, "hKeepAlivePeriod": -1}}`, &splithttp.XmuxConfig{
+			MaxConcurrency:   &splithttp.RangeConfig{From: 1, To: 2},
+			MaxConnections:   &splithttp.RangeConfig{},
+			CMaxReuseTimes:   &splithttp.RangeConfig{},
+			HMaxRequestTimes: &splithttp.RangeConfig{From: 100, To: 100},
+			HMaxReusableSecs: &splithttp.RangeConfig{},
+			HKeepAlivePeriod: -1,
+		}},
+	} {
+		config := new(XDriveConfig)
+		if err := json.Unmarshal([]byte(c.input), config); err != nil {
+			t.Fatalf("%s: Unmarshal: %v", c.input, err)
+		}
+		built, err := config.Build()
+		if err != nil {
+			t.Fatalf("%s: Build: %v", c.input, err)
+		}
+		if got := built.(*xdrive.Config).Xmux; !proto.Equal(got, c.want) {
+			t.Errorf("%s: xmux is %v, want %v", c.input, got, c.want)
+		}
+	}
+
+	config := new(XDriveConfig)
+	if err := json.Unmarshal([]byte(`{"service": "template", "template": {}, "xmux": {"maxConnections": 2, "maxConcurrency": 8}}`), config); err != nil {
+		t.Fatalf("Unmarshal: %v", err)
+	}
+	if _, err := config.Build(); err == nil {
+		t.Error("Build accepted maxConnections with maxConcurrency")
+	}
+}

infra/conf/tun.go

@@ -6,9 +6,7 @@ import (
 	"math/big"
 	"net"
 	"runtime"
-	"slices"
 	"strconv"
-	"strings"
 
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/proxy/tun"
@@ -39,25 +37,22 @@ func (v *TunConfig) Build() (proto.Message, error) {
 		AutoSystemRoutingTable: v.AutoSystemRoutingTable,
 		AutoSystemDnsToGateway: v.AutoSystemDnsToGateway,
 	}
-	for _, leak := range v.AutoSystemWfpBlockLeak {
-		switch leak := strings.ToLower(leak); leak {
-		case "dns", "misconfigtun":
-			config.AutoSystemWfpBlockLeak = append(config.AutoSystemWfpBlockLeak, leak)
-		default:
-			return nil, errors.New("unknown autoSystemWfpBlockLeak value: ", leak)
-		}
+	leaks, err := tun.ExpandWfpBlockLeak(v.AutoSystemWfpBlockLeak)
+	if err != nil {
+		return nil, err
 	}
+	config.AutoSystemWfpBlockLeak = leaks
 	// Each option needs other settings on the system it takes effect on: the
-	// filters go along with the routes of autoSystemRoutingTable, "dns" lets
-	// DNS through the TUN only, and autoSystemDnsToGateway points the system
-	// DNS at the gateway.
+	// filters go along with the routes of autoSystemRoutingTable, keeping the
+	// system's DNS inside the TUN needs DNS servers on it, and
+	// autoSystemDnsToGateway points the system DNS at the gateway.
 	switch runtime.GOOS {
 	case "windows":
-		if len(config.AutoSystemWfpBlockLeak) > 0 && len(v.AutoSystemRoutingTable) == 0 {
+		if len(leaks) > 0 && len(v.AutoSystemRoutingTable) == 0 {
 			return nil, errors.New("autoSystemWfpBlockLeak needs autoSystemRoutingTable to be set")
 		}
-		if slices.Contains(config.AutoSystemWfpBlockLeak, "dns") && len(v.DNS) == 0 {
-			return nil, errors.New(`autoSystemWfpBlockLeak "dns" needs dns to be set`)
+		if tun.BlocksSystemDNS(leaks) && len(v.DNS) == 0 {
+			return nil, errors.New(`autoSystemWfpBlockLeak "dns", "udp/53", "tcp/53" or "windnsclient" needs dns to be set`)
 		}
 	case "linux", "freebsd":
 		if v.AutoSystemDnsToGateway && len(v.Gateway) == 0 {

infra/conf/tun_test.go

@@ -29,12 +29,17 @@ func TestTunConfigAutoSystem(t *testing.T) {
 		{
 			Input:  `{"name": "xray0", "dns": ["1.1.1.1"], "autoSystemRoutingTable": ["0.0.0.0/0"], "autoSystemWfpBlockLeak": ["dns", "misconfigtun"]}`,
 			Parser: loadJSON(creator),
-			Output: &tun.Config{Name: "xray0", Desc: "Wintun", MTU: 1500, DNS: []string{"1.1.1.1"}, AutoSystemRoutingTable: []string{"0.0.0.0/0"}, AutoOutboundsInterface: "auto", AutoSystemWfpBlockLeak: []string{"dns", "misconfigtun"}},
+			Output: &tun.Config{Name: "xray0", Desc: "Wintun", MTU: 1500, DNS: []string{"1.1.1.1"}, AutoSystemRoutingTable: []string{"0.0.0.0/0"}, AutoOutboundsInterface: "auto", AutoSystemWfpBlockLeak: []string{"udp/53", "tcp/53", "windnsclient", "tcp/853", "udp/853", "misconfigtun"}},
 		},
 		{
 			Input:  `{"name": "xray0", "dns": ["1.1.1.1"], "autoSystemRoutingTable": ["0.0.0.0/0"], "autoSystemWfpBlockLeak": ["DNS"]}`,
 			Parser: loadJSON(creator),
-			Output: &tun.Config{Name: "xray0", Desc: "Wintun", MTU: 1500, DNS: []string{"1.1.1.1"}, AutoSystemRoutingTable: []string{"0.0.0.0/0"}, AutoOutboundsInterface: "auto", AutoSystemWfpBlockLeak: []string{"dns"}},
+			Output: &tun.Config{Name: "xray0", Desc: "Wintun", MTU: 1500, DNS: []string{"1.1.1.1"}, AutoSystemRoutingTable: []string{"0.0.0.0/0"}, AutoOutboundsInterface: "auto", AutoSystemWfpBlockLeak: []string{"udp/53", "tcp/53", "windnsclient", "tcp/853", "udp/853"}},
+		},
+		{
+			Input:  `{"name": "xray0", "autoSystemRoutingTable": ["0.0.0.0/0"], "autoSystemWfpBlockLeak": ["TCP/853", "udp/853", "tcp/0853"]}`,
+			Parser: loadJSON(creator),
+			Output: &tun.Config{Name: "xray0", Desc: "Wintun", MTU: 1500, AutoSystemRoutingTable: []string{"0.0.0.0/0"}, AutoOutboundsInterface: "auto", AutoSystemWfpBlockLeak: []string{"tcp/853", "udp/853"}},
 		},
 	})
 }
@@ -49,6 +54,9 @@ func TestTunConfigAutoSystemNeeds(t *testing.T) {
 		{`{"name": "xray0", "autoSystemWfpBlockLeak": ["misconfigtun"]}`, []string{"windows"}},
 		{`{"name": "xray0", "autoSystemRoutingTable": ["0.0.0.0/0"], "autoSystemWfpBlockLeak": ["misconfigtun"]}`, nil},
 		{`{"name": "xray0", "autoSystemRoutingTable": ["0.0.0.0/0"], "autoSystemWfpBlockLeak": ["dns"]}`, []string{"windows"}},
+		{`{"name": "xray0", "autoSystemRoutingTable": ["0.0.0.0/0"], "autoSystemWfpBlockLeak": ["udp/53"]}`, []string{"windows"}},
+		{`{"name": "xray0", "autoSystemRoutingTable": ["0.0.0.0/0"], "autoSystemWfpBlockLeak": ["windnsclient"]}`, []string{"windows"}},
+		{`{"name": "xray0", "autoSystemRoutingTable": ["0.0.0.0/0"], "autoSystemWfpBlockLeak": ["tcp/853", "udp/853"]}`, nil},
 		{`{"name": "xray0", "autoSystemDnsToGateway": true}`, []string{"linux", "freebsd"}},
 	} {
 		config := new(TunConfig)
@@ -62,11 +70,13 @@ func TestTunConfigAutoSystemNeeds(t *testing.T) {
 }
 
 func TestTunConfigAutoSystemWfpBlockLeakUnknown(t *testing.T) {
-	config := new(TunConfig)
-	if err := json.Unmarshal([]byte(`{"name": "xray0", "autoSystemWfpBlockLeak": ["dns", "ip"]}`), config); err != nil {
-		t.Fatal(err)
-	}
-	if _, err := config.Build(); err == nil {
-		t.Error("an unknown autoSystemWfpBlockLeak value was accepted")
+	for _, value := range []string{"ip", "tcp/0", "icmp/1"} {
+		config := new(TunConfig)
+		if err := json.Unmarshal([]byte(`{"name": "xray0", "autoSystemWfpBlockLeak": ["dns", "`+value+`"]}`), config); err != nil {
+			t.Fatal(err)
+		}
+		if _, err := config.Build(); err == nil {
+			t.Errorf("autoSystemWfpBlockLeak value %q was accepted", value)
+		}
 	}
 }

infra/conf/xray.go

@@ -237,10 +237,11 @@ type OutboundDetourConfig struct {
 
 func requiresTransportSecurity(address *Address) bool {
 	if address == nil || address.Address == nil {
-		return false
+		return true
 	}
 	if address.Family().IsIP() {
-		return !geodata.GetPrivateIPMatcher().Match(address.IP())
+		ip := address.IP()
+		return !ip.IsPrivate() && !ip.IsLoopback() && !ip.IsLinkLocalUnicast()
 	}
 	domain := strings.TrimSuffix(strings.ToLower(address.Domain()), ".")
 	return !geodata.GetPrivateDomainMatcher().MatchAny(domain)
@@ -608,7 +609,6 @@ func (c *Config) Build() (*core.Config, error) {
 	config := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&dispatcher.Config{}),
-			serial.ToTypedMessage(&proxyman.InboundConfig{}),
 			serial.ToTypedMessage(&proxyman.OutboundConfig{}),
 		},
 	}
@@ -718,6 +718,9 @@ func (c *Config) Build() (*core.Config, error) {
 		config.App = append(config.App, serial.ToTypedMessage(r))
 	}
 
+	// Initialize the inbound module last to ensure inbound connections are handled correctly.
+	config.App = append(config.App, serial.ToTypedMessage(&proxyman.InboundConfig{}))
+
 	var inbounds []InboundDetourConfig
 
 	if len(c.InboundConfigs) > 0 {

infra/conf/xray_test.go

@@ -90,7 +90,6 @@ func TestXrayConfig(t *testing.T) {
 						AccessLogPath: "/var/log/xray/access.log",
 					}),
 					serial.ToTypedMessage(&dispatcher.Config{}),
-					serial.ToTypedMessage(&proxyman.InboundConfig{}),
 					serial.ToTypedMessage(&proxyman.OutboundConfig{}),
 					serial.ToTypedMessage(&router.Config{
 						DomainStrategy: router.Config_AsIs,
@@ -111,6 +110,7 @@ func TestXrayConfig(t *testing.T) {
 							},
 						},
 					}),
+					serial.ToTypedMessage(&proxyman.InboundConfig{}),
 				},
 				Inbound: []*core.InboundHandlerConfig{
 					{

infra/vprotogen/main.go

@@ -1,149 +1,87 @@
 package main
 
 import (
-	"errors"
+	"bytes"
+	"context"
 	"flag"
 	"fmt"
-	"go/build"
-	"io"
-	"net/http"
+	"io/fs"
 	"os"
 	"os/exec"
 	"path/filepath"
-	"regexp"
-	"runtime"
-	"strconv"
 	"strings"
+
+	"github.com/bufbuild/protocompile"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/reflect/protodesc"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/types/descriptorpb"
+	"google.golang.org/protobuf/types/pluginpb"
 )
 
-var directory = flag.String("pwd", "", "Working directory of Xray vprotogen.")
+var (
+	directory = flag.String("pwd", "", "Working directory of Xray vprotogen.")
+	mode      = flag.String("mode", "generate", "Execution mode. 'generate' (default) compiles and saves changes. 'check' reports out-of-date files and exits with non-zero.")
+)
 
-// 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")
+// topoSort sorts file descriptors so each dependency appears before files importing it.
+func topoSort(files []protoreflect.FileDescriptor) []*descriptorpb.FileDescriptorProto {
+	fileMap := make(map[string]protoreflect.FileDescriptor)
+	for _, f := range files {
+		fileMap[f.Path()] = f
+	}
+
+	visited := make(map[string]bool)
+	var sorted []*descriptorpb.FileDescriptorProto
+
+	var visit func(fd protoreflect.FileDescriptor)
+	visit = func(fd protoreflect.FileDescriptor) {
+		if visited[fd.Path()] {
+			return
 		}
-		return file, nil
-	}
-	dir, err := os.UserConfigDir()
-	if err != nil {
-		return "", err
-	}
-	if dir == "" {
-		return "", errors.New("missing user-config dir")
-	}
-	return filepath.Join(dir, "go", "env"), nil
-}
+		visited[fd.Path()] = true
 
-// 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 strings.EqualFold(strings.TrimSpace(envKeyValue[0]), key) {
-			runtimeEnv = strings.TrimSpace(envKeyValue[1])
+		imports := fd.Imports()
+		for i := 0; i < imports.Len(); i++ {
+			if dep, ok := fileMap[imports.Get(i).Path()]; ok {
+				visit(dep)
+			}
 		}
+		sorted = append(sorted, protodesc.ToFileDescriptorProto(fd))
 	}
-	return runtimeEnv, nil
+
+	for _, f := range files {
+		visit(f)
+	}
+	return sorted
 }
 
-// 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 whichProtoc(suffix, targetedVersion string) (string, error) {
-	protoc := "protoc" + suffix
-
-	path, err := exec.LookPath(protoc)
+func runPlugin(pluginName, pwd string, req *pluginpb.CodeGeneratorRequest) (*pluginpb.CodeGeneratorResponse, error) {
+	reqBytes, err := proto.Marshal(req)
 	if err != nil {
-		return "", fmt.Errorf(`
-Command "%s" not found.
-Make sure that %s is in your system path or current path.
-Download %s v%s or later from https://github.com/protocolbuffers/protobuf/releases
-`, protoc, protoc, protoc, targetedVersion)
+		return nil, err
 	}
-	return path, nil
-}
 
-func getProjectProtocVersion(url string) (string, error) {
-	resp, err := http.Get(url)
-	if err != nil {
-		return "", errors.New("can not get the version of protobuf used in xray project")
-	}
-	defer resp.Body.Close()
-	body, err := io.ReadAll(resp.Body)
-	if err != nil {
-		return "", errors.New("can not read from body")
-	}
-	versionRegexp := regexp.MustCompile(`\/\/\s*protoc\s*v\d+\.(\d+\.\d+)`)
-	matched := versionRegexp.FindStringSubmatch(string(body))
-	return matched[1], nil
-}
+	cmd := exec.Command("go", "tool", pluginName)
+	cmd.Dir = pwd
+	cmd.Stdin = bytes.NewReader(reqBytes)
+	cmd.Env = os.Environ()
+	var stdout, stderr bytes.Buffer
+	cmd.Stdout = &stdout
+	cmd.Stderr = &stderr
 
-func getInstalledProtocVersion(protocPath string) (string, error) {
-	cmd := exec.Command(protocPath, "--version")
-	cmd.Env = append(cmd.Env, os.Environ()...)
-	output, cmdErr := cmd.CombinedOutput()
-	if cmdErr != nil {
-		return "", cmdErr
+	if err := cmd.Run(); err != nil {
+		return nil, fmt.Errorf("%v: %s", err, stderr.String())
 	}
-	versionRegexp := regexp.MustCompile(`protoc\s*(\d+\.\d+)`)
-	matched := versionRegexp.FindStringSubmatch(string(output))
-	return matched[1], nil
-}
 
-func parseVersion(s string, width int) int64 {
-	strList := strings.Split(s, ".")
-	format := fmt.Sprintf("%%s%%0%ds", width)
-	v := ""
-	for _, value := range strList {
-		v = fmt.Sprintf(format, v, value)
+	var resp pluginpb.CodeGeneratorResponse
+	if err := proto.Unmarshal(stdout.Bytes(), &resp); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal response: %w", err)
 	}
-	var result int64
-	var err error
-	if result, err = strconv.ParseInt(v, 10, 64); err != nil {
-		return 0
+	if resp.GetError() != "" {
+		return nil, fmt.Errorf("%s", resp.GetError())
 	}
-	return result
-}
-
-func needToUpdate(targetedVersion, installedVersion string) bool {
-	vt := parseVersion(targetedVersion, 4)
-	vi := parseVersion(installedVersion, 4)
-	return vt > vi
+	return &resp, nil
 }
 
 func main() {
@@ -154,106 +92,147 @@ func main() {
 	flag.Parse()
 
 	if !filepath.IsAbs(*directory) {
-		pwd, wdErr := os.Getwd()
-		if wdErr != nil {
+		pwd, err := os.Getwd()
+		if err != nil {
 			fmt.Println("Can not get current working directory.")
 			os.Exit(1)
 		}
 		*directory = filepath.Join(pwd, *directory)
 	}
-
 	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"
-	}
-
-	/*
-		targetedVersion, err := getProjectProtocVersion("https://raw.githubusercontent.com/XTLS/Xray-core/HEAD/core/config.pb.go")
-		if err != nil {
-			fmt.Println(err)
-			os.Exit(1)
-		}
-	*/
-	targetedVersion := ""
-
-	protoc, err := whichProtoc(suffix, targetedVersion)
-	if err != nil {
-		fmt.Println(err)
+	isCheck := false
+	switch *mode {
+	case "generate", "":
+		isCheck = false
+	case "check":
+		isCheck = true
+	default:
+		fmt.Fprintf(os.Stderr, "Unrecognized 'mode': %s. Use 'generate' or 'check'.\n", *mode)
 		os.Exit(1)
 	}
 
-	installedVersion, err := getInstalledProtocVersion(protoc)
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
+	if isCheck {
+		fmt.Println("Checking for out-of-date Protobuf generated files...")
 	}
 
-	if needToUpdate(targetedVersion, installedVersion) {
-		fmt.Printf(`
-You are using an old protobuf version, please update to v%s or later.
-Download it from https://github.com/protocolbuffers/protobuf/releases
-
-    * Protobuf version used in xray project: v%s
-    * Protobuf version you have installed: v%s
-
-`, targetedVersion, targetedVersion, installedVersion)
-		os.Exit(1)
-	}
-
-	protoFilesMap := make(map[string][]string)
-	walkErr := filepath.Walk(pwd, func(path string, info os.FileInfo, err error) error {
-		if err != nil {
-			fmt.Println(err)
+	var protoFiles []string
+	var pbCount int
+	err := filepath.WalkDir(pwd, func(path string, d fs.DirEntry, err error) error {
+		if err != nil || d.IsDir() {
 			return err
 		}
-
-		if info.IsDir() {
-			return nil
+		if strings.HasSuffix(d.Name(), ".proto") {
+			rel, _ := filepath.Rel(pwd, path)
+			protoFiles = append(protoFiles, filepath.ToSlash(rel))
 		}
-
-		dir := filepath.Dir(path)
-		filename := filepath.Base(path)
-		if strings.HasSuffix(filename, ".proto") {
-			path = path[len(pwd)+1:]
-			protoFilesMap[dir] = append(protoFilesMap[dir], path)
+		if strings.HasSuffix(d.Name(), ".pb.go") {
+			pbCount++
 		}
-
 		return nil
 	})
-	if walkErr != nil {
-		fmt.Println(walkErr)
+	if err != nil {
+		fmt.Println("Walk error:", err)
+		os.Exit(1)
+	}
+	if len(protoFiles) == 0 {
+		if isCheck && pbCount > 0 {
+			fmt.Fprintf(os.Stderr, "Found %d .pb.go files without any .proto files. Remove these orphaned files.\n", pbCount)
+			os.Exit(1)
+		}
+		return
+	}
+
+	compiler := protocompile.Compiler{
+		Resolver: protocompile.WithStandardImports(&protocompile.SourceResolver{
+			ImportPaths: []string{pwd},
+		}),
+		SourceInfoMode: protocompile.SourceInfoStandard,
+	}
+
+	linkedFiles, err := compiler.Compile(context.Background(), protoFiles...)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Protobuf compilation failed:\n%v\n", err)
 		os.Exit(1)
 	}
 
-	for _, files := range protoFilesMap {
-		for _, relProtoFile := range files {
-			args := []string{
-				"--go_out", pwd,
-				"--go_opt", "paths=source_relative",
-				"--go-grpc_out", pwd,
-				"--go-grpc_opt", "paths=source_relative",
-				"--plugin", "protoc-gen-go=" + filepath.Join(GOBIN, "protoc-gen-go"+suffix),
-				"--plugin", "protoc-gen-go-grpc=" + filepath.Join(GOBIN, "protoc-gen-go-grpc"+suffix),
+	var fdList []protoreflect.FileDescriptor
+	for _, f := range linkedFiles {
+		fdList = append(fdList, f)
+	}
+
+	req := &pluginpb.CodeGeneratorRequest{
+		FileToGenerate: protoFiles,
+		Parameter:      proto.String("paths=source_relative"),
+		ProtoFile:      topoSort(fdList),
+		// TODO: replace with unknown in the future
+		CompilerVersion: &pluginpb.Version{
+			Major: proto.Int32(6),
+			Minor: proto.Int32(33),
+			Patch: proto.Int32(5),
+		},
+	}
+
+	var diffCount int
+	generatedFiles := make(map[string]struct{})
+	for _, plugin := range []string{"protoc-gen-go", "protoc-gen-go-grpc"} {
+		resp, err := runPlugin(plugin, pwd, req)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "%s failed: %v\n", plugin, err)
+			os.Exit(1)
+		}
+
+		for _, f := range resp.File {
+			targetPath := filepath.Join(pwd, filepath.FromSlash(f.GetName()))
+			generatedFiles[targetPath] = struct{}{}
+			content := []byte(f.GetContent())
+
+			hasDiff := false
+			existing, err := os.ReadFile(targetPath)
+			if err != nil {
+				hasDiff = true
+			} else {
+				oldNorm := bytes.ReplaceAll(existing, []byte("\r\n"), []byte("\n"))
+				newNorm := bytes.ReplaceAll(content, []byte("\r\n"), []byte("\n"))
+				if !bytes.Equal(oldNorm, newNorm) {
+					hasDiff = true
+				}
 			}
-			args = append(args, relProtoFile)
-			cmd := exec.Command(protoc, args...)
-			cmd.Env = append(cmd.Env, os.Environ()...)
-			cmd.Dir = pwd
-			output, cmdErr := cmd.CombinedOutput()
-			if len(output) > 0 {
-				fmt.Println(string(output))
-			}
-			if cmdErr != nil {
-				fmt.Println(cmdErr)
-				os.Exit(1)
+
+			if hasDiff {
+				diffCount++
+				fmt.Println(targetPath)
+
+				if isCheck {
+					continue
+				}
+
+				if err := os.MkdirAll(filepath.Dir(targetPath), 0o755); err != nil {
+					fmt.Fprintf(os.Stderr, "Error creating directory: %v\n", err)
+					os.Exit(1)
+				}
+				mode := os.FileMode(0o644)
+				if stat, err := os.Stat(targetPath); err == nil {
+					mode = stat.Mode().Perm()
+				}
+				if err := os.WriteFile(targetPath, content, mode); err != nil {
+					fmt.Fprintf(os.Stderr, "Error writing %s: %v\n", targetPath, err)
+					os.Exit(1)
+				}
 			}
 		}
 	}
+
+	if isCheck {
+		if pbCount != len(generatedFiles) {
+			fmt.Printf("Protobuf file count mismatch: found %d, expected %d. Remove orphaned files and regenerate.\n", pbCount, len(generatedFiles))
+			diffCount++
+		}
+		if diffCount > 0 {
+			fmt.Println("Protobuf generated file problem(s) found.")
+			fmt.Println("Please run 'go run ./infra/vprotogen' to regenerate them.")
+			os.Exit(1)
+		}
+		fmt.Println("All Protobuf generated file check has been passed.")
+	}
 }

main/commands/all/api/rules_add.go

@@ -92,6 +92,8 @@ func executeAddRules(cmd *base.Command, args []string) {
 		if err != nil {
 			base.Fatalf("failed to perform AddRule: %s", err)
 		}
+		// if multiple files are specified, use append to merge them instead of overriding previous one
+		shouldAppend = true
 		showJSONResponse(resp)
 	}
 }

main/commands/all/lua/sign.go

@@ -3,6 +3,7 @@ package lua
 import (
 	"os"
 	"path/filepath"
+	"strings"
 
 	xlua "github.com/xtls/xray-core/common/lua"
 	"github.com/xtls/xray-core/main/commands/base"
@@ -32,14 +33,13 @@ func executeSign(cmd *base.Command, args []string) {
 		cmd.Usage()
 	}
 
+	if !strings.EqualFold(filepath.Ext(args[0]), ".lua") {
+		base.Fatalf("Lua file extension must be .lua")
+	}
 	info, err := os.Stat(args[0])
 	if err != nil {
 		base.Fatalf("failed to inspect Lua file: %s", err)
 	}
-	if !info.Mode().IsRegular() {
-		base.Fatalf("Lua input is not a regular file: %s", args[0])
-	}
-
 	code, err := os.ReadFile(args[0])
 	if err != nil {
 		base.Fatalf("failed to read Lua file: %s", err)
@@ -67,14 +67,7 @@ func executeSign(cmd *base.Command, args []string) {
 
 func writeSignedFile(path string, code []byte, mode os.FileMode) error {
 	if info, err := os.Stat(path); err == nil {
-		if !info.Mode().IsRegular() {
-			return &os.PathError{Op: "write", Path: path, Err: os.ErrInvalid}
-		}
 		mode = info.Mode().Perm()
-		path, err = filepath.EvalSymlinks(path)
-		if err != nil {
-			return err
-		}
 	} else if !os.IsNotExist(err) {
 		return err
 	}

main/confloader/external/external.go

@@ -58,18 +58,10 @@ func readConfigFile(file *os.File) ([]byte, error) {
 		return nil, err
 	}
 	if info.Mode().IsRegular() {
-		path, err := filepath.Abs(file.Name())
-		if err != nil {
-			return nil, err
-		}
-		path, err = filepath.EvalSymlinks(path)
-		if err != nil {
-			return nil, err
-		}
-		switch strings.ToLower(filepath.Ext(path)) {
+		switch strings.ToLower(filepath.Ext(file.Name())) {
 		case ".jsonc", ".json", ".yml", ".yaml", ".toml", ".pb", ".protobuf":
 		default:
-			return nil, errors.New("unsupported config file extension: ", path)
+			return nil, errors.New("unsupported config file extension: ", file.Name())
 		}
 	}
 	return io.ReadAll(file)

proxy/dns/dns.go

@@ -381,6 +381,13 @@ func (h *Handler) handleIPQuery(id uint16, qType dnsmessage.Type, domain string,
 		errors.LogInfoInner(context.Background(), err, "pack message")
 		b.Release()
 		timer.SetTimeout(0)
+		return
+	}
+	if len(msgBytes) > buf.Size {
+		b.Release()
+		timer.SetTimeout(0)
+		errors.LogError(context.Background(), "DNS response message too large")
+		return
 	}
 	b.Resize(0, int32(len(msgBytes)))
 

proxy/dokodemo/config.pb.go

@@ -23,14 +23,14 @@ const (
 )
 
 type Config struct {
-	state          protoimpl.MessageState `protogen:"open.v1"`
-	RewriteAddress *net.IPOrDomain        `protobuf:"bytes,1,opt,name=rewrite_address,json=rewriteAddress,proto3" json:"rewrite_address,omitempty"`
-	RewritePort    uint32                 `protobuf:"varint,2,opt,name=rewrite_port,json=rewritePort,proto3" json:"rewrite_port,omitempty"`
-	PortMap        map[string]string      `protobuf:"bytes,3,rep,name=port_map,json=portMap,proto3" json:"port_map,omitempty" protobuf_key:"bytes,1,opt,name=key" protobuf_val:"bytes,2,opt,name=value"`
+	state protoimpl.MessageState `protogen:"open.v1"`
 	// List of networks that the Dokodemo accepts.
-	AllowedNetworks []net.Network `protobuf:"varint,7,rep,packed,name=allowed_networks,json=allowedNetworks,proto3,enum=xray.common.net.Network" json:"allowed_networks,omitempty"`
-	FollowRedirect  bool          `protobuf:"varint,5,opt,name=follow_redirect,json=followRedirect,proto3" json:"follow_redirect,omitempty"`
-	UserLevel       uint32        `protobuf:"varint,6,opt,name=user_level,json=userLevel,proto3" json:"user_level,omitempty"`
+	AllowedNetworks []net.Network     `protobuf:"varint,7,rep,packed,name=allowed_networks,json=allowedNetworks,proto3,enum=xray.common.net.Network" json:"allowed_networks,omitempty"`
+	RewriteAddress  *net.IPOrDomain   `protobuf:"bytes,1,opt,name=rewrite_address,json=rewriteAddress,proto3" json:"rewrite_address,omitempty"`
+	RewritePort     uint32            `protobuf:"varint,2,opt,name=rewrite_port,json=rewritePort,proto3" json:"rewrite_port,omitempty"`
+	PortMap         map[string]string `protobuf:"bytes,3,rep,name=port_map,json=portMap,proto3" json:"port_map,omitempty" protobuf_key:"bytes,1,opt,name=key" protobuf_val:"bytes,2,opt,name=value"`
+	FollowRedirect  bool              `protobuf:"varint,5,opt,name=follow_redirect,json=followRedirect,proto3" json:"follow_redirect,omitempty"`
+	UserLevel       uint32            `protobuf:"varint,6,opt,name=user_level,json=userLevel,proto3" json:"user_level,omitempty"`
 	unknownFields   protoimpl.UnknownFields
 	sizeCache       protoimpl.SizeCache
 }
@@ -65,6 +65,13 @@ func (*Config) Descriptor() ([]byte, []int) {
 	return file_proxy_dokodemo_config_proto_rawDescGZIP(), []int{0}
 }
 
+func (x *Config) GetAllowedNetworks() []net.Network {
+	if x != nil {
+		return x.AllowedNetworks
+	}
+	return nil
+}
+
 func (x *Config) GetRewriteAddress() *net.IPOrDomain {
 	if x != nil {
 		return x.RewriteAddress
@@ -86,13 +93,6 @@ func (x *Config) GetPortMap() map[string]string {
 	return nil
 }
 
-func (x *Config) GetAllowedNetworks() []net.Network {
-	if x != nil {
-		return x.AllowedNetworks
-	}
-	return nil
-}
-
 func (x *Config) GetFollowRedirect() bool {
 	if x != nil {
 		return x.FollowRedirect
@@ -112,11 +112,11 @@ var File_proxy_dokodemo_config_proto protoreflect.FileDescriptor
 const file_proxy_dokodemo_config_proto_rawDesc = "" +
 	"\n" +
 	"\x1bproxy/dokodemo/config.proto\x12\x13xray.proxy.dokodemo\x1a\x18common/net/address.proto\x1a\x18common/net/network.proto\"\xff\x02\n" +
-	"\x06Config\x12D\n" +
+	"\x06Config\x12C\n" +
+	"\x10allowed_networks\x18\a \x03(\x0e2\x18.xray.common.net.NetworkR\x0fallowedNetworks\x12D\n" +
 	"\x0frewrite_address\x18\x01 \x01(\v2\x1b.xray.common.net.IPOrDomainR\x0erewriteAddress\x12!\n" +
 	"\frewrite_port\x18\x02 \x01(\rR\vrewritePort\x12C\n" +
-	"\bport_map\x18\x03 \x03(\v2(.xray.proxy.dokodemo.Config.PortMapEntryR\aportMap\x12C\n" +
-	"\x10allowed_networks\x18\a \x03(\x0e2\x18.xray.common.net.NetworkR\x0fallowedNetworks\x12'\n" +
+	"\bport_map\x18\x03 \x03(\v2(.xray.proxy.dokodemo.Config.PortMapEntryR\aportMap\x12'\n" +
 	"\x0ffollow_redirect\x18\x05 \x01(\bR\x0efollowRedirect\x12\x1d\n" +
 	"\n" +
 	"user_level\x18\x06 \x01(\rR\tuserLevel\x1a:\n" +
@@ -141,13 +141,13 @@ var file_proxy_dokodemo_config_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
 var file_proxy_dokodemo_config_proto_goTypes = []any{
 	(*Config)(nil),         // 0: xray.proxy.dokodemo.Config
 	nil,                    // 1: xray.proxy.dokodemo.Config.PortMapEntry
-	(*net.IPOrDomain)(nil), // 2: xray.common.net.IPOrDomain
-	(net.Network)(0),       // 3: xray.common.net.Network
+	(net.Network)(0),       // 2: xray.common.net.Network
+	(*net.IPOrDomain)(nil), // 3: xray.common.net.IPOrDomain
 }
 var file_proxy_dokodemo_config_proto_depIdxs = []int32{
-	2, // 0: xray.proxy.dokodemo.Config.rewrite_address:type_name -> xray.common.net.IPOrDomain
-	1, // 1: xray.proxy.dokodemo.Config.port_map:type_name -> xray.proxy.dokodemo.Config.PortMapEntry
-	3, // 2: xray.proxy.dokodemo.Config.allowed_networks:type_name -> xray.common.net.Network
+	2, // 0: xray.proxy.dokodemo.Config.allowed_networks:type_name -> xray.common.net.Network
+	3, // 1: xray.proxy.dokodemo.Config.rewrite_address:type_name -> xray.common.net.IPOrDomain
+	1, // 2: xray.proxy.dokodemo.Config.port_map:type_name -> xray.proxy.dokodemo.Config.PortMapEntry
 	3, // [3:3] is the sub-list for method output_type
 	3, // [3:3] is the sub-list for method input_type
 	3, // [3:3] is the sub-list for extension type_name

proxy/freedom/freedom.go

@@ -229,14 +229,19 @@ func (h *Handler) blockDelay(rule *FinalRule) time.Duration {
 func (h *Handler) blackhole(ctx context.Context, input buf.Reader, output buf.Writer, rule *FinalRule, dest *net.Destination) error {
 	delay := h.blockDelay(rule)
 	errors.LogInfo(ctx, "blocked target: ", *dest, ", blackholing connection for ", delay)
-	timer := time.AfterFunc(delay, func() {
+	defer common.Close(output)
+	done := make(chan struct{})
+	go func() { // a DispatchLink inbound's reader ignores Interrupt, so don't wait for this copy
+		_ = buf.Copy(input, buf.Discard)
+		close(done)
+	}()
+	select {
+	case <-done:
+	case <-time.After(delay):
 		common.Interrupt(input)
 		common.Interrupt(output)
 		errors.LogInfo(ctx, "closed blackholed connection to blocked target: ", *dest)
-	})
-	defer timer.Stop()
-	defer common.Close(output)
-	_ = buf.Copy(input, buf.Discard)
+	}
 	return nil
 }
 

proxy/http/client.go

@@ -10,6 +10,7 @@ import (
 	"net/url"
 	"sync"
 	"text/template"
+	"time"
 
 	"github.com/xtls/xray-core/common"
 	"github.com/xtls/xray-core/common/buf"
@@ -86,7 +87,13 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 	user := server.User
 	var conn stat.Connection
 
-	mbuf, _ := link.Reader.ReadMultiBuffer()
+	var mbuf buf.MultiBuffer
+	if reader, ok := link.Reader.(buf.TimeoutReader); ok {
+		// Don't wait forever: server-first protocols (SMTP, FTP, MySQL...) send nothing until the server greets.
+		mbuf, _ = reader.ReadMultiBufferTimeout(time.Millisecond * 500)
+	} else {
+		mbuf, _ = link.Reader.ReadMultiBuffer()
+	}
 	len := mbuf.Len()
 	firstPayload := bytespool.Alloc(len)
 	mbuf, _ = buf.SplitBytes(mbuf, firstPayload)
@@ -234,7 +241,8 @@ func setUpHTTPTunnel(ctx context.Context, dest net.Destination, target string, u
 			return nil, err
 		}
 
-		resp, err := http.ReadResponse(bufio.NewReader(rawConn), req)
+		reader := bufio.NewReader(rawConn)
+		resp, err := http.ReadResponse(reader, req)
 		if err != nil {
 			rawConn.Close()
 			return nil, err
@@ -245,6 +253,11 @@ func setUpHTTPTunnel(ctx context.Context, dest net.Destination, target string, u
 			rawConn.Close()
 			return nil, errors.New("Proxy responded with non 200 code: " + resp.Status)
 		}
+		// Tunneled bytes (e.g. a server-first greeting) may arrive in the same read as the 200 response.
+		if n := reader.Buffered(); n > 0 {
+			early, _ := reader.Peek(n)
+			return &earlyDataConn{Conn: rawConn, early: early}, nil
+		}
 		return rawConn, nil
 	}
 
@@ -375,6 +388,21 @@ func (h *http2Conn) Close() error {
 	return h.out.Close()
 }
 
+// earlyDataConn returns the bytes read ahead together with the CONNECT response before reading from Conn.
+type earlyDataConn struct {
+	net.Conn
+	early []byte
+}
+
+func (c *earlyDataConn) Read(p []byte) (int, error) {
+	if len(c.early) > 0 {
+		n := copy(p, c.early)
+		c.early = c.early[n:]
+		return n, nil
+	}
+	return c.Conn.Read(p)
+}
+
 func init() {
 	common.Must(common.RegisterConfig((*ClientConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
 		return NewClient(ctx, config.(*ClientConfig))

proxy/socks/temp_udp_listen.go

@@ -2,10 +2,10 @@ package socks
 
 import (
 	"context"
-	"net"
 	"sync/atomic"
 	"time"
 
+	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/common/signal"
 )
 
@@ -14,6 +14,9 @@ func NewTempUDPConn(udpConn net.PacketConn, tcpConn net.Conn, expectedRemote *ne
 		PacketConn:        udpConn,
 		AssociatedTCPConn: tcpConn,
 	}
+	t.Timer = signal.CancelAfterInactivity(context.Background(), func() {
+		t.Close()
+	}, net.ConnIdleTimeout)
 	t.ExpectedRemote.Store(expectedRemote)
 	return t
 }
@@ -60,9 +63,7 @@ func (c *TempUDPConn) RemoteAddr() net.Addr {
 }
 
 func (c *TempUDPConn) SetTimeout(d time.Duration) {
-	c.Timer = signal.CancelAfterInactivity(context.Background(), func() {
-		c.Close()
-	}, d)
+	c.Timer.SetTimeout(d)
 }
 
 func (c *TempUDPConn) Close() error {

proxy/tun/README.md

@@ -219,8 +219,10 @@ After the start network adapter with the name you chose in the config will be cr
 
 When `dns` is set, those servers are applied to the adapter. Windows is kept from registering the TUN's addresses in DNS, and its DNS cache is flushed when the TUN starts and stops.
 
-With `autoSystemWfpBlockLeak`, which needs `autoSystemRoutingTable` (the config is rejected otherwise), Xray also adds Windows Filtering Platform filters that keep two kinds of traffic of every program but Xray itself from leaving outside the TUN, each chosen by a value in the list, e.g. `"autoSystemWfpBlockLeak": ["dns", "misconfigtun"]`:
-- `"dns"` (needs `dns`, the config is rejected otherwise): DNS (port 53) only goes through the TUN. Windows keeps sending name queries to the DNS servers of the other interfaces as well, out through those interfaces whatever the routes say, and other programs reach a resolver on the local network (e.g. `192.168.1.1` handed out by DHCP) through its more specific LAN route instead of the TUN. On Windows 11 and Server 2022 and later, where those queries may also go over HTTPS or TLS, Windows' DNS Client service cannot connect outside the TUN at all, except for name resolution on the local network (LLMNR, mDNS). The `dns` servers therefore have to lie within `gateway` or `autoSystemRoutingTable` (a warning is logged otherwise), and DNS servers that should be reached directly belong in Xray's own `dns` settings.
+With `autoSystemWfpBlockLeak`, which needs `autoSystemRoutingTable` (the config is rejected otherwise), Xray also adds Windows Filtering Platform filters that keep traffic of every program but Xray itself from leaving outside the TUN, each kind chosen by a value in the list, e.g. `"autoSystemWfpBlockLeak": ["dns", "misconfigtun"]`:
+- `"tcp/<port>"`, `"udp/<port>"`: connections to that TCP or UDP port only go through the TUN, e.g. `"tcp/853"`.
+- `"windnsclient"`: Windows' DNS Client service cannot connect outside the TUN at all, except for name resolution on the local network (LLMNR, mDNS). On Windows 11 and Server 2022 and later, it may send name queries over HTTPS or TLS, to any port. Earlier versions only query port 53, so there it does nothing.
+- `"dns"`: stands for `"udp/53"`, `"tcp/53"`, `"windnsclient"`, `"tcp/853"` (DNS over TLS) and `"udp/853"` (DNS over QUIC). Windows keeps sending name queries to the DNS servers of the other interfaces as well, out through those interfaces whatever the routes say, and other programs reach a resolver on the local network (e.g. `192.168.1.1` handed out by DHCP) through its more specific LAN route instead of the TUN. Keeping the system's DNS inside the TUN like this, with `"dns"`, `"udp/53"`, `"tcp/53"` or `"windnsclient"`, needs `dns` (the config is rejected otherwise). The `dns` servers then have to lie within `gateway` or `autoSystemRoutingTable` (a warning is logged otherwise), and DNS servers that should be reached directly belong in Xray's own `dns` settings.
 - `"misconfigtun"`: an IP version without routes in `autoSystemRoutingTable`, IPv4 or IPv6, is blocked entirely, in both directions, as it would bypass the TUN. Only loopback and what Windows itself needs on the local link (DHCP, and for IPv6 neighbor and multicast listener discovery) remain allowed. An address of that version in `gateway` is not needed: without one, Windows gives the TUN link-local addresses itself, an IPv6 one at once and an IPv4 one from `169.254.0.0/16` after some seconds (until then, IPv4 routed to the TUN is unreachable), and what is routed to the TUN goes through it with those.
 
 With the filters in place, Xray's own connections out also get past Windows Firewall's block rules (other firewalls may still block them), while connections to Xray's inbounds stay subject to them.

proxy/tun/config.pb.go

@@ -7,12 +7,11 @@
 package tun
 
 import (
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
 	reflect "reflect"
 	sync "sync"
 	unsafe "unsafe"
-
-	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
-	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
 )
 
 const (

proxy/tun/packet.go

@@ -41,8 +41,9 @@ const (
 type packet struct {
 	proto    byte
 	src, dst netip.Addr
-	// payload is what follows the IP header
+	// payload is what follows the IP header, without the last rest bytes of it when they are in other buffers
 	payload []byte
+	rest    int
 	// fragment is set if payload is a part of what follows the IP header: the one at offset of the packet
 	// with the number id, which has more after it or not
 	fragment bool
@@ -51,8 +52,8 @@ type packet struct {
 	id       uint32
 }
 
-// parsePacket reads the IP header of b
-func parsePacket(b []byte) (p packet, ok bool) {
+// parsePacket reads the IP header of a packet that is b and rest bytes after it
+func parsePacket(b []byte, rest int) (p packet, ok bool) {
 	if len(b) < ipv4HeaderSize {
 		return p, false
 	}
@@ -60,7 +61,7 @@ func parsePacket(b []byte) (p packet, ok bool) {
 	case 4:
 		size := int(b[0]&0xf) * 4
 		total := int(binary.BigEndian.Uint16(b[2:]))
-		if size < ipv4HeaderSize || total < size || total > len(b) {
+		if size < ipv4HeaderSize || total < size || total > len(b)+rest {
 			return p, false
 		}
 		if f := binary.BigEndian.Uint16(b[6:]); f&0x3fff != 0 {
@@ -69,19 +70,19 @@ func parsePacket(b []byte) (p packet, ok bool) {
 		p.proto = b[9]
 		p.src = netip.AddrFrom4([4]byte(b[12:16]))
 		p.dst = netip.AddrFrom4([4]byte(b[16:20]))
-		p.payload = b[size:total]
+		p.payload, p.rest = b[size:min(total, len(b))], max(total-len(b), 0)
 	case 6:
 		if len(b) < ipv6HeaderSize {
 			return p, false
 		}
 		total := ipv6HeaderSize + int(binary.BigEndian.Uint16(b[4:]))
-		if total > len(b) {
+		if total > len(b)+rest {
 			return p, false
 		}
 		p.proto = b[6]
 		p.src = netip.AddrFrom16([16]byte(b[8:24]))
 		p.dst = netip.AddrFrom16([16]byte(b[24:40]))
-		p.payload = b[ipv6HeaderSize:total]
+		p.payload, p.rest = b[ipv6HeaderSize:min(total, len(b))], max(total-len(b), 0)
 		// hop-by-hop options, routing, destination options
 		for p.proto == 0 || p.proto == 43 || p.proto == 60 {
 			if len(p.payload) < 8 {

proxy/tun/stack.go

@@ -71,6 +71,10 @@ type stack struct {
 	udp    *udpConnectionHandler
 	// addresses are what connections are opened from
 	addresses []netip.Addr
+	// bufs is what read reads a packet into if the tun is a segmenter, one after the other, the headers in the first.
+	// One that keep took is nil. joined is for a packet that is in more than one and is needed in one piece
+	bufs   buf.MultiBuffer
+	joined []byte
 
 	mu    sync.Mutex
 	conns map[flow]*tcpConn
@@ -149,26 +153,66 @@ func (s *stack) Close() error {
 
 // read takes the packets of the tun until it is closed
 func (s *stack) read() {
-	// a tun that does not split segments gives them as large as a packet can be
-	b := make([]byte, packetRoom+1<<16)
-	for {
-		b, err := s.tun.ReadPacket(b)
-		if err != nil {
-			s.mu.Lock()
-			closed := s.closed
-			s.mu.Unlock()
-			if !closed {
-				errors.LogErrorInner(s.ctx, err, "[tun] failed to read a packet, no more are read")
+	var err error
+	if s.segmenter != nil {
+		err = s.readSegments()
+	} else {
+		// as large as a packet can be, whatever the MTU is
+		b := make([]byte, packetRoom+1<<16)
+		for err == nil {
+			var p []byte
+			if p, err = s.tun.ReadPacket(b); err == nil {
+				s.Input(p)
 			}
-			return
 		}
-		s.Input(b)
 	}
+	s.mu.Lock()
+	closed := s.closed
+	s.mu.Unlock()
+	if !closed {
+		errors.LogErrorInner(s.ctx, err, "[tun] failed to read a packet, no more are read")
+	}
+}
+
+// readSegments is read for a tun that does not split segments and gives them as large as a packet can be.
+// They are read into buffers for a connection to keep what is large as it is, see keep
+func (s *stack) readSegments() error {
+	s.bufs = make(buf.MultiBuffer, (1<<16)/buf.Size)
+	defer buf.ReleaseMulti(s.bufs)
+	parts := make([][]byte, len(s.bufs))
+	var r room
+	for {
+		for i, b := range s.bufs {
+			if b == nil {
+				s.bufs[i] = buf.New()
+				_, _ = s.bufs[i].ReadFrom(&r)
+				parts[i] = r.b
+			}
+		}
+		n, err := s.segmenter.ReadParts(parts)
+		if err != nil {
+			return err
+		}
+		s.input(parts[0][:min(n, buf.Size)], max(n-buf.Size, 0))
+	}
+}
+
+// room takes what it is given to read into as read: that is the room of a Buffer as it is, not cleared
+type room struct{ b []byte }
+
+func (r *room) Read(b []byte) (int, error) {
+	r.b = b
+	return len(b), nil
 }
 
 // Input implements Stack. Several tunnels may hand over their packets at once
 func (s *stack) Input(b []byte) {
-	p, ok := parsePacket(b)
+	s.input(b, 0)
+}
+
+// input takes a packet that is b and rest bytes after it, in the bufs that follow the one that b is in
+func (s *stack) input(b []byte, rest int) {
+	p, ok := parsePacket(b, rest)
 	if !ok || p.src.Is4In6() || p.dst.Is4In6() || p.src.IsLoopback() || p.dst.IsLoopback() || p.dst.IsUnspecified() || p.src.IsMulticast() {
 		// nothing comes from many at once, and an address that stands for this machine itself is not one
 		// that the other side of a tun can ask for. Nor is an IPv6 address that stands for an IPv4 one, which
@@ -180,6 +224,10 @@ func (s *stack) Input(b []byte) {
 	}
 	// what was put together may be of two packets with one number, its checksum tells
 	verify := s.verify || p.fragment
+	if p.rest != 0 && (verify || p.proto != protoTCP) {
+		// only a segment of TCP that is not looked at can stay in pieces
+		p.payload, p.rest = s.whole(p.payload, p.rest), 0
+	}
 	if p.fragment {
 		p, ok = s.fragments.add(p)
 	}
@@ -196,6 +244,37 @@ func (s *stack) Input(b []byte) {
 	}
 }
 
+// whole returns in one piece what is b and rest bytes after it, in the bufs that follow the one that b is in
+func (s *stack) whole(b []byte, rest int) []byte {
+	if rest == 0 {
+		return b
+	}
+	s.joined = append(s.joined[:0], b...)
+	for i := 1; rest > 0; i++ {
+		n := min(rest, buf.Size)
+		s.joined = append(s.joined, s.bufs[i].BytesTo(int32(n))...)
+		rest -= n
+	}
+	return s.joined
+}
+
+// keep adds to mb what is b and rest bytes after it, in the bufs that follow the one that b is in: nothing is copied,
+// the buffers are taken for it and no longer read into
+func (s *stack) keep(mb buf.MultiBuffer, b []byte, rest int) buf.MultiBuffer {
+	// b ends where what was read into the first one does, or before it
+	first := s.bufs[0]
+	from := first.Cap() - int32(cap(b))
+	first.Resize(from, from+int32(len(b)))
+	mb, s.bufs[0] = append(mb, first), nil
+	for i := 1; rest > 0; i++ {
+		n := min(rest, buf.Size)
+		s.bufs[i].Resize(0, int32(n))
+		mb, s.bufs[i] = append(mb, s.bufs[i]), nil
+		rest -= n
+	}
+	return mb
+}
+
 // local returns the address that packets to remote are sent from
 func (s *stack) local(remote netip.Addr) (netip.Addr, error) {
 	for _, a := range s.addresses {
@@ -237,6 +316,7 @@ func (s *stack) handleTCP(p packet) {
 		window:  binary.BigEndian.Uint16(t[14:]),
 		options: t[tcpHeaderSize:size],
 		payload: t[size:],
+		rest:    p.rest,
 	}
 
 	s.mu.Lock()
@@ -283,7 +363,7 @@ func (s *stack) refuse(f flow, seg segment) {
 		binary.BigEndian.PutUint32(t[4:], seg.ack)
 		t[13] = tcpRst
 	} else {
-		ack := seg.seq + uint32(len(seg.payload))
+		ack := seg.seq + uint32(len(seg.payload)+seg.rest)
 		if seg.flags&(tcpSyn|tcpFin) != 0 {
 			ack++
 		}

proxy/tun/stack_test.go

@@ -65,6 +65,20 @@ func (l *link) Segments() bool {
 	return l.segments
 }
 
+// ReadParts implements segmenter
+func (l *link) ReadParts(parts [][]byte) (int, error) {
+	select {
+	case packet := <-l.in:
+		n := 0
+		for _, p := range parts {
+			n += copy(p, packet[n:])
+		}
+		return n, nil
+	case <-l.done:
+		return 0, io.EOF
+	}
+}
+
 // WriteSegment implements segmenter as the system does when it sends a segment on: a packet for every mss bytes
 func (l *link) WriteSegment(header []byte, payload [][]byte, mss int) error {
 	data := bytes.Join(payload, nil)
@@ -206,7 +220,7 @@ func (p *peer) receive() segment {
 func (p *peer) dialed() (segment, []byte) {
 	p.t.Helper()
 	b := p.packet()
-	packet, ok := parsePacket(b)
+	packet, ok := parsePacket(b, 0)
 	if !ok || packet.proto != protoTCP || len(packet.payload) < tcpHeaderSize {
 		p.t.Fatal("not a segment: ", b)
 	}
@@ -223,7 +237,7 @@ func (p *peer) segment(b []byte) segment {
 	} else if checksum(sum(b[:size], 0)) != 0 {
 		p.t.Fatal("wrong checksum of the ip header")
 	}
-	packet, ok := parsePacket(b)
+	packet, ok := parsePacket(b, 0)
 	if !ok || packet.proto != protoTCP || packet.src != p.dst.Addr() || packet.dst != p.src.Addr() {
 		p.t.Fatal("not a segment of the connection: ", b)
 	}
@@ -464,30 +478,90 @@ func TestTCPOutOfOrder(t *testing.T) {
 	read(t, a.conn, "jklmno")
 }
 
-// A segment is as large as the system makes it when the tun does not split what it reads.
+// A segment is as large as the system makes it when the tun does not split what it reads, and one that is large,
+// the next and all taken stays in the buffers that such a tun reads it into.
 func TestTCPLargeSegment(t *testing.T) {
-	conns := make(chan accepted, 1)
-	p, l := newPeer(t, "10.0.0.1:1234", "10.0.0.2:80")
-	newTestStack(t, l, accept(conns))
-	p.connect(nil)
-	a := take(t, conns)
+	for _, segments := range []bool{false, true} {
+		conns := make(chan accepted, 1)
+		p, l := newPeer(t, "10.0.0.1:1234", "10.0.0.2:80")
+		l.segments = segments
+		s := newTestStack(t, l, accept(conns))
+		sent := make([]byte, 200000)
+		rand.Read(sent)
+		// one of no connection is refused as a whole
+		p.send(p.seq, tcpPsh, nil, sent[:20000])
+		if r := p.receive(); r.flags != tcpRst|tcpAck || r.ack != p.seq+20000 {
+			t.Fatal("segments: ", segments, ", not refused: flags ", r.flags, ", ack ", r.ack-p.seq, " after its seq")
+		}
+		p.connect(nil)
+		a := take(t, conns)
 
-	sent := make([]byte, 60000)
-	rand.Read(sent)
-	p.send(p.seq, tcpAck|tcpPsh, nil, sent)
-	var received []byte
-	for len(received) < len(sent) {
-		mb, err := a.conn.(buf.Reader).ReadMultiBuffer()
-		if err != nil {
-			t.Fatal(err)
+		// one that waits for the one before it, that one, one with a part that came already, small ones around
+		// one that fits a buffer, and the rest
+		for _, part := range [][2]int{{60000, 90000}, {0, 60000}, {80000, 110000}, {110000, 110100}, {110100, 115100}, {115100, 118100}, {118100, 170000}, {170000, 200000}} {
+			p.send(p.seq+uint32(part[0]), tcpAck|tcpPsh, nil, sent[part[0]:part[1]])
 		}
-		for _, b := range mb {
-			received = append(received, b.Bytes()...)
+		// all of it is taken before anything is read, for the buffers to be as the stack put it in them
+		for r := p.receive(); r.ack != p.seq+uint32(len(sent)); r = p.receive() {
+		}
+		var received []byte
+		for len(received) < len(sent) {
+			mb, err := a.conn.(buf.Reader).ReadMultiBuffer()
+			if err != nil {
+				t.Fatal(err)
+			}
+			// a buffer that was read into starts with the headers, one that was copied to is full
+			if kept := mb[0].Len() == buf.Size-ipv4HeaderSize-tcpHeaderSize; len(received) == 0 && kept != segments {
+				t.Fatal("segments: ", segments, ", the first buffer has ", mb[0].Len(), " bytes")
+			}
+			for _, b := range mb {
+				// and a small one is copied to where the one before it ends
+				if b.Len() < 1000 {
+					t.Fatal("segments: ", segments, ", a buffer of ", b.Len(), " bytes")
+				}
+				received = append(received, b.Bytes()...)
+			}
+			buf.ReleaseMulti(mb)
+		}
+		if !bytes.Equal(received, sent) {
+			t.Fatal("segments: ", segments, ", read something else than what was sent")
+		}
+
+		// no more is taken than the window while nobody reads, of the last one a part,
+		// and what is taken is acknowledged when a quarter of the window is
+		p.seq += uint32(len(sent))
+		sent = make([]byte, (int(s.window)/50000+1)*50000)
+		rand.Read(sent)
+		for i := 0; i < len(sent); i += 50000 {
+			p.send(p.seq+uint32(i), tcpAck|tcpPsh, nil, sent[i:i+50000])
+		}
+		for acked := p.seq; ; {
+			r := p.receive()
+			if taken := int32(r.ack - p.seq); taken > s.window {
+				t.Fatal("segments: ", segments, ", ", taken, " bytes taken with a window of ", s.window)
+			} else if taken == s.window {
+				break
+			}
+			// one that acknowledges nothing more tells that the window opened for what was read before
+			if r.ack != acked && int32(r.ack-acked) < s.window/4 {
+				t.Fatal("segments: ", segments, ", ", r.ack-acked, " bytes acknowledged with a window of ", s.window)
+			}
+			acked = r.ack
+		}
+		received = received[:0]
+		for len(received) < int(s.window) {
+			mb, err := a.conn.(buf.Reader).ReadMultiBuffer()
+			if err != nil {
+				t.Fatal(err)
+			}
+			for _, b := range mb {
+				received = append(received, b.Bytes()...)
+			}
+			buf.ReleaseMulti(mb)
+		}
+		if !bytes.Equal(received, sent[:s.window]) {
+			t.Fatal("segments: ", segments, ", read something else than what the window took")
 		}
-		buf.ReleaseMulti(mb)
-	}
-	if !bytes.Equal(received, sent) {
-		t.Fatal("read something else than what was sent")
 	}
 }
 
@@ -1082,13 +1156,20 @@ func TestTCPSynAfterClose(t *testing.T) {
 }
 
 // A UDP packet starts a connection, which answers from any address, and an echo request is answered.
+// Both can be larger than a buffer of a tun that reads into more than one.
 func TestUDPAndICMP(t *testing.T) {
-	for _, test := range []struct{ src, dst, other string }{
-		{"10.0.0.1:1234", "10.0.0.2:53", "10.0.0.3:5353"},
-		{"[fd00::1]:1234", "[fd00::2]:53", "[fd00::3]:5353"},
+	large := make([]byte, 20000)
+	rand.Read(large)
+	for _, test := range []struct {
+		src, dst, other string
+		segments        bool
+	}{
+		{"10.0.0.1:1234", "10.0.0.2:53", "10.0.0.3:5353", false},
+		{"[fd00::1]:1234", "[fd00::2]:53", "[fd00::3]:5353", true},
 	} {
 		conns := make(chan accepted, 1)
 		p, l := newPeer(t, test.src, test.dst)
+		l.segments = test.segments
 		newTestStack(t, l, accept(conns))
 
 		var b [ipv6HeaderSize + udpHeaderSize]byte
@@ -1105,6 +1186,13 @@ func TestUDPAndICMP(t *testing.T) {
 			t.Fatal("read ", mb.String(), " from ", a.conn.RemoteAddr(), " to ", a.dest, ", error: ", err)
 		}
 		buf.ReleaseMulti(mb)
+		binary.BigEndian.PutUint16(u[4:], uint16(udpHeaderSize+len(large)))
+		setIPLength(b[:n], n+udpHeaderSize+len(large))
+		l.in <- append(b[:n+udpHeaderSize:n+udpHeaderSize], large...)
+		if mb, err = a.conn.(buf.Reader).ReadMultiBuffer(); err != nil || len(mb) != 1 || !bytes.Equal(mb[0].Bytes(), large) {
+			t.Fatal("read ", mb.Len(), " bytes of a large packet, error: ", err)
+		}
+		buf.ReleaseMulti(mb)
 
 		for _, from := range []string{test.dst, test.other} {
 			answer := buf.FromBytes([]byte("defg"))
@@ -1114,7 +1202,7 @@ func TestUDPAndICMP(t *testing.T) {
 				t.Fatal(err)
 			}
 			raw := p.packet()
-			packet, ok := parsePacket(raw)
+			packet, ok := parsePacket(raw, 0)
 			u := packet.payload
 			// the system may have to split it on the way to where it goes
 			if !ok || raw[0]>>4 == 4 && raw[6] != 0 || packet.proto != protoUDP || netip.AddrPortFrom(packet.src, binary.BigEndian.Uint16(u)).String() != from ||
@@ -1133,12 +1221,12 @@ func TestUDPAndICMP(t *testing.T) {
 			proto, request, reply = protoICMPv6, 128, 129
 		}
 		n = putIPHeader(b[:], proto, p.src.Addr(), p.dst.Addr())
-		setIPLength(b[:n], n+12)
-		l.in <- append(b[:n:n], request, 0, 0, 0, 1, 2, 3, 4, 'a', 'b', 'c', 'd')
-		packet, ok := parsePacket(p.packet())
+		setIPLength(b[:n], n+8+len(large))
+		l.in <- append(append(b[:n:n], request, 0, 0, 0, 1, 2, 3, 4), large...)
+		packet, ok := parsePacket(p.joined(), 0)
 		m := packet.payload
-		if !ok || packet.proto != proto || packet.src != p.dst.Addr() || packet.dst != p.src.Addr() || m[0] != reply || string(m[4:]) != "\x01\x02\x03\x04abcd" {
-			t.Fatal("wrong echo reply: ", packet)
+		if !ok || packet.proto != proto || packet.src != p.dst.Addr() || packet.dst != p.src.Addr() || m[0] != reply || string(m[4:8]) != "\x01\x02\x03\x04" || !bytes.Equal(m[8:], large) {
+			t.Fatal("wrong echo reply of ", len(m), " bytes from ", packet.src, " to ", packet.dst)
 		}
 		var ip [ipv6HeaderSize]byte
 		size := putIPHeader(ip[:], proto, packet.src, packet.dst)
@@ -1373,7 +1461,7 @@ func TestUDPDial(t *testing.T) {
 				t.Fatal("wrong header of the packet to ", to, ": ", raw[:ipv4HeaderSize])
 			}
 			numbers[to][binary.BigEndian.Uint16(raw[4:])] = true
-			packet, ok := parsePacket(raw)
+			packet, ok := parsePacket(raw, 0)
 			u := packet.payload
 			if !ok || packet.proto != protoUDP || netip.AddrPortFrom(packet.src, binary.BigEndian.Uint16(u)) != local ||
 				netip.AddrPortFrom(packet.dst, binary.BigEndian.Uint16(u[2:])) != to || string(u[udpHeaderSize:]) != "abc" {
@@ -1395,7 +1483,7 @@ func TestUDPDial(t *testing.T) {
 		if _, err := conn.WriteTo([]byte("abc"), &net.UDPAddr{IP: across.Addr().AsSlice(), Port: int(across.Port())}); err != nil {
 			t.Fatal(err)
 		}
-		if packet, ok := parsePacket(p.packet()); !ok || packet.proto != protoUDP || packet.dst != across.Addr() ||
+		if packet, ok := parsePacket(p.packet(), 0); !ok || packet.proto != protoUDP || packet.dst != across.Addr() ||
 			netip.AddrPortFrom(packet.src, binary.BigEndian.Uint16(packet.payload)) != acrossLocal {
 			t.Fatal("wrong packet to ", across, ": ", packet)
 		}
@@ -1407,7 +1495,7 @@ func TestUDPDial(t *testing.T) {
 		// a stack that takes no connections is one host: it answers a ping of its address and of no other
 		l.in <- ping(p.src.Addr(), netip.MustParseAddrPort(test.other).Addr())
 		l.in <- ping(p.src.Addr(), local.Addr())
-		if packet, ok := parsePacket(p.packet()); !ok || packet.src != local.Addr() || packet.dst != p.src.Addr() || packet.payload[0]&^129 != 0 {
+		if packet, ok := parsePacket(p.packet(), 0); !ok || packet.src != local.Addr() || packet.dst != p.src.Addr() || packet.payload[0]&^129 != 0 {
 			t.Fatal("wrong echo reply: ", packet)
 		}
 		p.silent(20 * time.Millisecond)
@@ -1873,7 +1961,7 @@ func TestFragments(t *testing.T) {
 		if err := a.conn.(buf.Writer).WriteMultiBuffer(buf.MultiBuffer{buf.FromBytes(sent)}); err != nil {
 			t.Fatal(err)
 		}
-		packet, ok := parsePacket(p.joined())
+		packet, ok := parsePacket(p.joined(), 0)
 		u := packet.payload
 		if !ok || packet.fragment || packet.proto != protoUDP || netip.AddrPortFrom(packet.src, binary.BigEndian.Uint16(u)) != p.dst ||
 			netip.AddrPortFrom(packet.dst, binary.BigEndian.Uint16(u[2:])) != p.src || int(binary.BigEndian.Uint16(u[4:])) != len(u) || !bytes.Equal(u[udpHeaderSize:], sent) {
@@ -1898,7 +1986,7 @@ func TestFragments(t *testing.T) {
 		mixed := split(summed(udpPacket(p.src, p.dst, bytes.Repeat([]byte{1}, 2000))), 1024, 11)
 		l.in <- mixed[0]
 		l.in <- split(summed(udpPacket(p.src, p.dst, bytes.Repeat([]byte{2}, 2000))), 1024, 11)[1]
-		packet, ok = parsePacket(p.joined())
+		packet, ok = parsePacket(p.joined(), 0)
 		m = packet.payload
 		if !ok || packet.proto != proto || packet.src != p.dst.Addr() || packet.dst != p.src.Addr() || m[0] != reply || !bytes.Equal(m[8:], sent) {
 			t.Fatal("wrong echo reply: ", packet.src, packet.dst, packet.proto, len(m))
@@ -2040,7 +2128,7 @@ func TestChecksumsAndLoopback(t *testing.T) {
 		l.in <- damaged(echo)
 		p.silent(50 * time.Millisecond)
 		l.in <- echo
-		if packet, ok := parsePacket(p.packet()); !ok || packet.proto != proto || string(packet.payload[4:]) != "\x01\x02\x03\x04abcd" {
+		if packet, ok := parsePacket(p.packet(), 0); !ok || packet.proto != proto || string(packet.payload[4:]) != "\x01\x02\x03\x04abcd" {
 			t.Fatal("wrong echo reply: ", packet)
 		}
 

proxy/tun/tcp_lightweight.go

@@ -49,6 +49,9 @@ const (
 	// tcpParts of how many parts of what was written it is made at most
 	tcpSegment = math.MaxUint16 - ipv6HeaderSize - tcpHeaderSize
 	tcpParts   = 7
+	// tcpKept is how large a payload is at least for the buffers that it was read into to be kept. A smaller one
+	// is copied to where the one before it ends, for a reader to get buffers that are full
+	tcpKept = buf.Size / 2
 
 	// tcpTick is how often a connection that waits for something looks at what it waits for
 	tcpTick = 100 * time.Millisecond
@@ -87,7 +90,9 @@ type segment struct {
 	flags    byte
 	window   uint16
 	options  []byte
-	payload  []byte
+	// payload is without its last rest bytes when those are in other buffers of the stack, see stack.whole
+	payload []byte
+	rest    int
 }
 
 // nextOption returns the first option of o and what follows it, kind is zero when there is none
@@ -749,6 +754,12 @@ func (c *tcpConn) space() uint32 {
 
 // receive takes the payload of a segment. c.mu is held
 func (c *tcpConn) receive(s segment) {
+	// what is large, the next and all taken stays in the buffers that it was read into
+	size := len(s.payload) + s.rest
+	keep := c.stack.bufs != nil && size >= tcpKept && s.seq == c.rcvNxt && size <= int(c.window-c.rcvLen)
+	if !keep {
+		s.payload = c.stack.whole(s.payload, s.rest)
+	}
 	seq, payload, fin := s.seq, s.payload, s.flags&tcpFin != 0
 	if len(payload) == 0 && !fin {
 		if int32(c.rcvNxt-seq) > 0 {
@@ -789,9 +800,14 @@ func (c *tcpConn) receive(s segment) {
 		return
 	}
 
-	c.rcvQueue = buf.MergeBytes(c.rcvQueue, payload)
-	c.rcvLen += int32(len(payload))
-	c.rcvNxt += uint32(len(payload))
+	if keep {
+		c.rcvQueue = c.stack.keep(c.rcvQueue, payload, s.rest)
+	} else {
+		size = len(payload)
+		c.rcvQueue = buf.MergeBytes(c.rcvQueue, payload)
+	}
+	c.rcvLen += int32(size)
+	c.rcvNxt += uint32(size)
 	for !fin && len(c.rcvHeld) > 0 && int32(c.rcvNxt-c.rcvHeld[0].seq) >= 0 {
 		h := c.rcvHeld[0]
 		if before := int32(c.rcvNxt - h.seq); before < h.data.Len() {
@@ -809,7 +825,7 @@ func (c *tcpConn) receive(s segment) {
 	c.readable.Signal()
 	// the reader acknowledges what it takes, with one segment for all that came by then.
 	// It is not waited for when it does not read for long
-	if fin || now || c.rcvNxt-c.rcvAcked >= tcpWindow/4 {
+	if fin || now || c.rcvNxt-c.rcvAcked >= uint32(c.window/4) {
 		c.sendAck()
 	} else {
 		c.arm(tcpTick)

proxy/tun/tun.go

@@ -16,10 +16,13 @@ type Tun interface {
 }
 
 // segmenter is a tun whose other side takes TCP segments that are larger than the MTU,
-// splits them only if it has to send them on, and completes their checksum then
+// splits them only if it has to send them on, and completes their checksum then.
+// What it sends comes as it is too, not split to the MTU
 type segmenter interface {
-	// Segments reports whether WriteSegment can be used
+	// Segments reports whether ReadParts and WriteSegment can be used
 	Segments() bool
+	// ReadParts waits for a packet, reads it into parts, one after the other, and returns its size
+	ReadParts(parts [][]byte) (int, error)
 	// WriteSegment writes a packet with a TCP segment whose payload is in parts, to be sent on with mss bytes
 	// of it at most in one. Its checksum is that of the pseudo-header only, not inverted
 	WriteSegment(header []byte, payload [][]byte, mss int) error

proxy/tun/tun_darwin.go

@@ -558,19 +558,16 @@ func ioctlPtr(fd int, req uint, arg unsafe.Pointer) error {
 }
 
 func setinterface(network, address string, fd uintptr, iface *net.Interface) error {
-	var err1, err2 error
-
 	switch network {
 	case "tcp6", "udp6", "ip6":
-		err1 = unix.SetsockoptInt(int(fd), unix.IPPROTO_IPV6, unix.IPV6_BOUND_IF, iface.Index)
-		fallthrough
+		// IPV6_BOUND_IF binds the IPv4 traffic of a dual-stack socket as
+		// well, and an IPv6 socket rejects IP_BOUND_IF with EINVAL.
+		return unix.SetsockoptInt(int(fd), unix.IPPROTO_IPV6, unix.IPV6_BOUND_IF, iface.Index)
 	case "tcp4", "udp4", "ip4":
-		err2 = unix.SetsockoptInt(int(fd), unix.IPPROTO_IP, unix.IP_BOUND_IF, iface.Index)
+		return unix.SetsockoptInt(int(fd), unix.IPPROTO_IP, unix.IP_BOUND_IF, iface.Index)
 	default:
 		panic(network + " " + address)
 	}
-
-	return errors.Join(err1, err2)
 }
 
 func findOutboundInterface(tunIndex int, fixedName string) (*net.Interface, error) {

proxy/tun/tun_darwin_test.go

@@ -3,7 +3,10 @@
 package tun
 
 import (
+	"context"
+	"net"
 	"sync"
+	"syscall"
 	"testing"
 	"time"
 
@@ -231,3 +234,40 @@ func TestWaitKqueueReportsPersistentFailure(t *testing.T) {
 		}
 	}
 }
+
+// TestSetinterfaceSocketFamilies binds each kind of socket Xray's dialers
+// open to lo0, including the dual-stack one Go opens for UDP.
+func TestSetinterfaceSocketFamilies(t *testing.T) {
+	lo, err := net.InterfaceByName("lo0")
+	if err != nil {
+		t.Skip(err)
+	}
+	lc := net.ListenConfig{Control: func(network, address string, c syscall.RawConn) error {
+		var err error
+		if controlErr := c.Control(func(fd uintptr) {
+			err = setinterface(network, address, fd, lo)
+		}); controlErr != nil {
+			return controlErr
+		}
+		return err
+	}}
+	for _, s := range []struct{ network, address string }{
+		{"udp", "0.0.0.0:0"}, // dual-stack
+		{"udp4", "127.0.0.1:0"},
+		{"udp6", "[::1]:0"},
+		{"tcp4", "127.0.0.1:0"},
+		{"tcp6", "[::1]:0"},
+	} {
+		var closer interface{ Close() error }
+		if s.network[:3] == "udp" {
+			closer, err = lc.ListenPacket(context.Background(), s.network, s.address)
+		} else {
+			closer, err = lc.Listen(context.Background(), s.network, s.address)
+		}
+		if err != nil {
+			t.Errorf("%s %s: %v", s.network, s.address, err)
+			continue
+		}
+		closer.Close()
+	}
+}

proxy/tun/tun_fd.go

@@ -6,6 +6,8 @@ import (
 	"encoding/binary"
 	"os"
 	"sync"
+	"syscall"
+	"unsafe"
 
 	"golang.org/x/sys/unix"
 )
@@ -22,6 +24,14 @@ type fdTun struct {
 	// vnet is the size of the virtio_net_hdr in front of every packet, zero if the tun has none.
 	// With it the system does not split what it sends to the tun and takes what is not split from it
 	vnet int
+	// raw is file for ReadParts, readv what it calls when there may be a packet, iovecs where that reads to:
+	// header, which takes the virtio_net_hdr, and the parts. read and readErr are what came of it
+	raw     syscall.RawConn
+	readv   func(fd uintptr) bool
+	header  [packetRoom]byte
+	iovecs  []unix.Iovec
+	read    int
+	readErr error
 
 	writeLock sync.RWMutex
 	closed    bool
@@ -29,7 +39,25 @@ type fdTun struct {
 
 // newFdTun takes a file descriptor that does not block
 func newFdTun(fd, vnet int) *fdTun {
-	return &fdTun{fd: fd, file: os.NewFile(uintptr(fd), "/dev/net/tun"), vnet: vnet}
+	t := &fdTun{fd: fd, file: os.NewFile(uintptr(fd), "/dev/net/tun"), vnet: vnet}
+	t.raw, _ = t.file.SyscallConn()
+	t.readv = func(fd uintptr) bool {
+		for {
+			n, _, errno := unix.Syscall(unix.SYS_READV, fd, uintptr(unsafe.Pointer(&t.iovecs[0])), uintptr(len(t.iovecs)))
+			switch errno {
+			case 0:
+				t.read, t.readErr = int(n), nil
+			case unix.EINTR:
+				continue
+			case unix.EAGAIN:
+				return false
+			default:
+				t.read, t.readErr = 0, errno
+			}
+			return true
+		}
+	}
+	return t
 }
 
 func (t *fdTun) ReadPacket(b []byte) ([]byte, error) {
@@ -38,6 +66,20 @@ func (t *fdTun) ReadPacket(b []byte) ([]byte, error) {
 	return b[min(t.vnet, n):n], err
 }
 
+// ReadParts implements segmenter
+func (t *fdTun) ReadParts(parts [][]byte) (int, error) {
+	t.iovecs = append(t.iovecs[:0], unix.Iovec{Base: &t.header[0]})
+	t.iovecs[0].SetLen(t.vnet)
+	for i, p := range parts {
+		t.iovecs = append(t.iovecs, unix.Iovec{Base: &p[0]})
+		t.iovecs[i+1].SetLen(len(p))
+	}
+	if err := t.raw.Read(t.readv); err != nil {
+		return 0, err
+	}
+	return max(t.read-t.vnet, 0), t.readErr
+}
+
 func (t *fdTun) WritePacket(header, payload []byte) error {
 	// a virtio_net_hdr of zeros leaves nothing to the system
 	var vnet [packetRoom]byte

proxy/tun/tun_fd_test.go

@@ -0,0 +1,66 @@
+//go:build linux
+
+package tun
+
+import (
+	"bytes"
+	"crypto/rand"
+	"testing"
+	"time"
+
+	"golang.org/x/sys/unix"
+)
+
+// A tun with a virtio_net_hdr reads one packet at a time into parts, without the header, waits for the next one,
+// and stops waiting when it is closed.
+func TestReadParts(t *testing.T) {
+	// what a tun is like: one packet for every read, and a file descriptor that does not block
+	fds, err := unix.Socketpair(unix.AF_UNIX, unix.SOCK_SEQPACKET|unix.SOCK_NONBLOCK|unix.SOCK_CLOEXEC, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer unix.Close(fds[1])
+	tun := newFdTun(fds[0], vnetSize)
+	defer tun.closeFile()
+
+	large := make([]byte, 20000)
+	rand.Read(large)
+	parts := [][]byte{make([]byte, 8192), make([]byte, 8192), make([]byte, 8192)}
+	send := func(packet []byte) {
+		if _, err := unix.Write(fds[1], append(bytes.Repeat([]byte{0xee}, vnetSize), packet...)); err != nil {
+			t.Error(err)
+		}
+	}
+	send(large)
+	send([]byte("small"))
+	for _, packet := range [][]byte{large, []byte("small")} {
+		n, err := tun.ReadParts(parts)
+		if err != nil || n != len(packet) || !bytes.Equal(bytes.Join(parts, nil)[:n], packet) {
+			t.Fatal("read ", n, " bytes of ", len(packet), ", error: ", err)
+		}
+	}
+
+	go func() {
+		time.Sleep(50 * time.Millisecond)
+		send([]byte("later"))
+	}()
+	if n, err := tun.ReadParts(parts); err != nil || string(parts[0][:n]) != "later" {
+		t.Fatal("read ", parts[0][:n], " after waiting, error: ", err)
+	}
+
+	read := make(chan error)
+	go func() {
+		_, err := tun.ReadParts(parts)
+		read <- err
+	}()
+	time.Sleep(50 * time.Millisecond)
+	tun.closeFile()
+	select {
+	case err := <-read:
+		if err == nil {
+			t.Fatal("read after the tun was closed")
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("still waits after the tun was closed")
+	}
+}

proxy/tun/tun_windows.go

@@ -247,30 +247,31 @@ startOver:
 	}
 
 	// With autoSystemWfpBlockLeak, once the system routes lead to the TUN,
-	// keep DNS ("dns", if dns is set), and an IP version no route of which
-	// leads to the TUN ("misconfigtun"), from leaving through the other
-	// interfaces. Addresses do not matter: without one of a version in
-	// gateway, Windows gives the TUN a link-local one.
-	leaks := t.options.AutoSystemWfpBlockLeak
-	blockDNS := slices.Contains(leaks, "dns") && len(dns) > 0
-	blockIPv4 := slices.Contains(leaks, "misconfigtun") && !route4
-	blockIPv6 := slices.Contains(leaks, "misconfigtun") && !route6
-	if (route4 || route6) && (blockDNS || blockIPv4 || blockIPv6) {
-		if t.wfp, err = blockLeaks(t.luid, blockDNS, blockIPv4, blockIPv6); err != nil {
-			var blocked []string
-			for _, b := range []struct {
-				on   bool
-				what string
-			}{{blockDNS, "DNS"}, {blockIPv4, "IPv4"}, {blockIPv6, "IPv6"}} {
-				if b.on {
-					blocked = append(blocked, b.what)
-				}
-			}
-			// Rather no TUN than a leaking one.
-			return errors.New("unable to block ", strings.Join(blocked, " and "), " outside the TUN (remove autoSystemWfpBlockLeak to run without)").Base(err)
+	// keep connections to the ports given ("dns" stands for those of DNS),
+	// Windows' DNS Client service, and an IP version no route of which leads
+	// to the TUN ("misconfigtun"), from leaving through the other interfaces.
+	// Addresses do not matter: without one of a version in gateway, Windows
+	// gives the TUN a link-local one.
+	leaks, err := ExpandWfpBlockLeak(t.options.AutoSystemWfpBlockLeak)
+	if err != nil {
+		return err
+	}
+	block := newLeakFilters(leaks, route4, route6)
+	if route4 || route6 {
+		if slices.Contains(leaks, "windnsclient") && !block.dnsClient {
+			errors.LogInfo(context.Background(), "[tun] windnsclient skipped: before Windows 11 and Server 2022, the DNS Client service only queries port 53")
 		}
-		errors.LogInfo(context.Background(), "[tun] outside the TUN, blocked DNS: ", blockDNS, ", blocked IPv4: ", blockIPv4, ", blocked IPv6: ", blockIPv6)
-		if blockDNS {
+		if block.systemDNS() && len(dns) == 0 {
+			return errors.New("keeping the system's DNS inside the TUN needs dns to be set")
+		}
+	}
+	if blocked := block.String(); (route4 || route6) && blocked != "" {
+		if t.wfp, err = blockLeaks(t.luid, block); err != nil {
+			// Rather no TUN than a leaking one.
+			return errors.New("unable to block ", blocked, " outside the TUN (remove autoSystemWfpBlockLeak to run without)").Base(err)
+		}
+		errors.LogInfo(context.Background(), "[tun] blocked outside the TUN: ", blocked)
+		if block.systemDNS() {
 			covered := slices.Clone(addresses)
 			for _, route := range routesData {
 				covered = append(covered, route.Destination)
@@ -401,6 +402,15 @@ func resolveOnOwn() *savedResolver {
 		if internet.IsSkippedDNSServer(address) {
 			return nil, errors.New("skipped DNS server ", address)
 		}
+		// A socket of the server's IP version only needs that version bound
+		// to the interface, which a dual-stack one would need both of.
+		if ap, err := netip.ParseAddrPort(address); err == nil && (network == "udp" || network == "tcp") {
+			if ap.Addr().Unmap().Is4() {
+				network += "4"
+			} else {
+				network += "6"
+			}
+		}
 		return dialer.DialContext(ctx, network, address)
 	}
 	net.DefaultResolver.PreferGo = true
@@ -558,10 +568,22 @@ func setinterface(network, address string, fd uintptr, iface *net.Interface) err
 
 	switch network {
 	case "tcp6", "udp6", "ip6":
+		dualStack := false
+		if network == "udp6" {
+			ipv6Only, err := windows.GetsockoptInt(windows.Handle(fd), windows.IPPROTO_IPV6, windows.IPV6_V6ONLY)
+			if err != nil {
+				return internet.NewBindError(err)
+			}
+			dualStack = ipv6Only == 0
+		}
 		err1 = windows.SetsockoptInt(windows.Handle(fd), windows.IPPROTO_IPV6, IPV6_UNICAST_IF, iface.Index)
 		if network == "udp6" {
 			err2 = windows.SetsockoptInt(windows.Handle(fd), windows.IPPROTO_IPV6, windows.IPV6_MULTICAST_IF, iface.Index)
 		}
+		// Only dual-stack UDP can send to both IPv4 and IPv6 destinations.
+		if !dualStack {
+			break
+		}
 		fallthrough
 	case "tcp4", "udp4", "ip4":
 		err3 = windows.SetsockoptInt(windows.Handle(fd), windows.IPPROTO_IP, IP_UNICAST_IF, *(*int)(unsafe.Pointer(&index[0])))
@@ -572,7 +594,10 @@ func setinterface(network, address string, fd uintptr, iface *net.Interface) err
 		panic(network + " " + address)
 	}
 
-	return errors.Combine(err1, err2, err3, err4)
+	if err := errors.Combine(err1, err2, err3, err4); err != nil {
+		return internet.NewBindError(err)
+	}
+	return nil
 }
 
 func findOutboundInterface(tunIndex int, fixedName string) (*net.Interface, error) {

proxy/tun/tun_windows_wfp.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"runtime"
 	"slices"
+	"strings"
 	"unsafe"
 
 	"github.com/xtls/xray-core/common/errors"
@@ -170,19 +171,79 @@ func condition(field *windows.GUID, typ uint32, value uintptr) fwpmFilterConditi
 	}
 }
 
+// leakFilters is what blockLeaks keeps from leaving outside the TUN.
+type leakFilters struct {
+	ports      []leakPort // connections to these ports
+	dnsClient  bool       // Windows' DNS Client service
+	ipv4, ipv6 bool       // an IP version altogether
+}
+
+// newLeakFilters turns expanded autoSystemWfpBlockLeak values into the filters
+// for a TUN that the routes of route4 (IPv4) and route6 (IPv6) lead to.
+func newLeakFilters(leaks []string, route4, route6 bool) leakFilters {
+	var block leakFilters
+	for _, leak := range leaks {
+		switch leak {
+		case "windnsclient":
+			block.dnsClient = dnsClientUsesAnyPort()
+		case "misconfigtun":
+			block.ipv4, block.ipv6 = !route4, !route6
+		default:
+			if port, ok := parseLeakPort(leak); ok {
+				block.ports = append(block.ports, port)
+			}
+		}
+	}
+	return block
+}
+
+// String lists what block keeps inside the TUN, or is empty for nothing.
+func (block leakFilters) String() string {
+	var blocked []string
+	for _, port := range block.ports {
+		blocked = append(blocked, port.String())
+	}
+	for _, b := range []struct {
+		on   bool
+		what string
+	}{{block.dnsClient, "windnsclient"}, {block.ipv4, "IPv4"}, {block.ipv6, "IPv6"}} {
+		if b.on {
+			blocked = append(blocked, b.what)
+		}
+	}
+	return strings.Join(blocked, ", ")
+}
+
+// systemDNS tells whether block keeps the system's DNS inside the TUN.
+func (block leakFilters) systemDNS() bool {
+	return block.dnsClient || slices.ContainsFunc(block.ports, func(port leakPort) bool { return port.port == 53 })
+}
+
+// dnsClientUsesAnyPort tells whether Windows' DNS Client service may send its
+// queries over HTTPS or TLS, and so to any port, which it does since Windows 11
+// and Server 2022 (build 20348). Earlier versions only query port 53, and may
+// run the service in one process with others, which its filters would catch
+// as well.
+func dnsClientUsesAnyPort() bool {
+	_, _, build := windows.RtlGetNtVersionNumbers()
+	return build >= 20348
+}
+
 // blockLeaks keeps traffic from leaving through interfaces other than tun,
 // for every program but Xray itself, whose outbounds (DNS included) use the
 // other interfaces on purpose:
 //
-//   - dns: DNS (port 53) may only go through the TUN. Windows sends a name
-//     query to the DNS servers of all interfaces, not only to those of the TUN:
-//     to the first server of each interface, then to all of them when no answer
-//     arrives within a second or two. It sends the queries for the servers of
-//     an interface out through that interface, whatever the routes say, and
-//     other programs reach an on-link resolver, like 192.168.1.1 from DHCP,
-//     through its LAN route, which is more specific than the TUN's default
-//     route. Since Windows 11 and Server 2022, Windows may also send its
-//     queries over HTTPS or TLS, so there its DNS Client service may not
+//   - ports: connections to these TCP or UDP ports may only go through the
+//     TUN, those of DNS (53), DNS over TLS (TCP 853) and DNS over QUIC (UDP
+//     853) with "dns". Windows sends a name query to the DNS servers of all
+//     interfaces, not only to those of the TUN: to the first server of each
+//     interface, then to all of them when no answer arrives within a second or
+//     two. It sends the queries for the servers of an interface out through
+//     that interface, whatever the routes say, and other programs reach an
+//     on-link resolver, like 192.168.1.1 from DHCP, through its LAN route,
+//     which is more specific than the TUN's default route.
+//   - dnsClient: since Windows 11 and Server 2022, Windows may also send its
+//     queries over HTTPS or TLS, to any port, so its DNS Client service may not
 //     connect outside the TUN at all, except for name resolution on the local
 //     link (mDNS, LLMNR).
 //   - ipv4, ipv6: no IPv4, or no IPv6, at all, in either direction, for a TUN
@@ -196,7 +257,7 @@ func condition(field *windows.GUID, typ uint32, value uintptr) fwpmFilterConditi
 //
 // The filters live in a dynamic WFP session: closing the returned engine handle
 // with closeWFPEngine deletes them, and so does Windows when the process dies.
-func blockLeaks(tun winipcfg.LUID, dns, ipv4, ipv6 bool) (windows.Handle, error) {
+func blockLeaks(tun winipcfg.LUID, block leakFilters) (windows.Handle, error) {
 	engine, err := openWFPEngine()
 	if err != nil {
 		return 0, err
@@ -205,7 +266,7 @@ func blockLeaks(tun winipcfg.LUID, dns, ipv4, ipv6 bool) (windows.Handle, error)
 		closeWFPEngine(engine)
 		return 0, errors.New("FwpmTransactionBegin0 failed").Base(err)
 	}
-	err = addLeakFilters(engine, tun, dns, ipv4, ipv6)
+	err = addLeakFilters(engine, tun, block)
 	if err == nil {
 		if err = fwpmResult(procFwpmTransactionCommit0.Call(uintptr(engine))); err != nil {
 			err = errors.New("FwpmTransactionCommit0 failed").Base(err)
@@ -242,7 +303,7 @@ func closeWFPEngine(engine windows.Handle) {
 
 // addLeakFilters adds the filters of blockLeaks in a sublayer of their own.
 // blockLeaks runs it in a transaction, so that they take effect all at once.
-func addLeakFilters(engine windows.Handle, tun winipcfg.LUID, dns, ipv4, ipv6 bool) error {
+func addLeakFilters(engine windows.Handle, tun winipcfg.LUID, block leakFilters) error {
 	exe, err := os.Executable()
 	if err != nil {
 		return err
@@ -285,51 +346,55 @@ func addLeakFilters(engine windows.Handle, tun winipcfg.LUID, dns, ipv4, ipv6 bo
 	// hard permit. Connections from outside to Xray get an ordinary one, so
 	// that firewalls keep guarding its inbounds.
 	self := condition(&fwpmConditionALEAppID, fwpByteBlobType, uintptr(unsafe.Pointer(appID)))
-	dns53 := condition(&fwpmConditionIPRemotePort, fwpUint16, 53)
-	// DNS goes through the TUN when its local address is the TUN's, and it
-	// also leaves, or arrives, through the TUN. The local address alone
+	// A connection goes through the TUN when its local address is the TUN's,
+	// and it also leaves, or arrives, through the TUN. The local address alone
 	// decides by default, but with weak host sending or receiving enabled,
 	// packets of the TUN's address can use other interfaces. (The next hop,
 	// the interface replies would leave by, is not known for arriving ones.)
 	onTUN := func(field *windows.GUID) fwpmFilterCondition0 {
 		return condition(field, fwpUint64, uintptr(unsafe.Pointer(tunLUID)))
 	}
-	out := []fwpmFilterCondition0{dns53, onTUN(&fwpmConditionIPLocalInterface), onTUN(&fwpmConditionIPNexthopInterface)}
-	in := []fwpmFilterCondition0{dns53, onTUN(&fwpmConditionIPLocalInterface), onTUN(&fwpmConditionIPArrivalInterface)}
 	for _, layer := range []struct {
-		key        *windows.GUID
-		selfFlags  uint32
-		throughTUN []fwpmFilterCondition0
+		key       *windows.GUID
+		selfFlags uint32
+		via       *windows.GUID // the interface that has to be the TUN as well
 	}{
-		{&fwpmLayerALEAuthConnectV4, fwpmFilterFlagClearActionRight, out},
-		{&fwpmLayerALEAuthRecvAcceptV4, 0, in},
-		{&fwpmLayerALEAuthConnectV6, fwpmFilterFlagClearActionRight, out},
-		{&fwpmLayerALEAuthRecvAcceptV6, 0, in},
+		{&fwpmLayerALEAuthConnectV4, fwpmFilterFlagClearActionRight, &fwpmConditionIPNexthopInterface},
+		{&fwpmLayerALEAuthRecvAcceptV4, 0, &fwpmConditionIPArrivalInterface},
+		{&fwpmLayerALEAuthConnectV6, fwpmFilterFlagClearActionRight, &fwpmConditionIPNexthopInterface},
+		{&fwpmLayerALEAuthRecvAcceptV6, 0, &fwpmConditionIPArrivalInterface},
 	} {
 		if err := add(layer.key, "permit Xray", layer.selfFlags, fwpActionPermit, 4, self); err != nil {
 			return err
 		}
-		if dns {
-			if err := add(layer.key, "permit DNS through the TUN", 0, fwpActionPermit, 3, layer.throughTUN...); err != nil {
+		for _, port := range block.ports {
+			protocol := uintptr(windows.IPPROTO_UDP)
+			if port.tcp {
+				protocol = windows.IPPROTO_TCP
+			}
+			toPort := []fwpmFilterCondition0{
+				condition(&fwpmConditionIPProtocol, fwpUint8, protocol),
+				condition(&fwpmConditionIPRemotePort, fwpUint16, uintptr(port.port)),
+			}
+			throughTUN := slices.Concat(toPort, []fwpmFilterCondition0{onTUN(&fwpmConditionIPLocalInterface), onTUN(layer.via)})
+			if err := add(layer.key, "permit "+port.String()+" through the TUN", 0, fwpActionPermit, 3, throughTUN...); err != nil {
 				return err
 			}
-			if err := add(layer.key, "block DNS", 0, fwpActionBlock, 2, dns53); err != nil {
+			if err := add(layer.key, "block "+port.String(), 0, fwpActionBlock, 2, toPort...); err != nil {
 				return err
 			}
 		}
 	}
 
-	// Since Windows 11 and Server 2022 (build 20348), the DNS Client service
-	// may also send the queries for an interface's servers over HTTPS or TLS,
-	// out through that interface and to any port. So there it may only
-	// connect through the TUN, except for mDNS and LLMNR, which stay on the
-	// local link (over an IP version only while it is not blocked altogether).
-	// Earlier versions only query port 53, and may run the service in one
-	// process with others, which the filters would catch as well. Like
-	// Windows Firewall's rules for it, they recognize the service by its SID,
+	// Since Windows 11 and Server 2022, the DNS Client service may also send
+	// the queries for an interface's servers over HTTPS or TLS, out through
+	// that interface and to any port. So there it may only connect through
+	// the TUN, except for mDNS and LLMNR, which stay on the local link (over
+	// an IP version only while it is not blocked altogether). Like Windows
+	// Firewall's rules for it, the filters recognize the service by its SID,
 	// which Windows puts in the token of its process: the security descriptor
 	// grants that SID the right to match (FWP_ACTRL_MATCH_FILTER, CC in SDDL).
-	if _, _, build := windows.RtlGetNtVersionNumbers(); dns && build >= 20348 {
+	if block.dnsClient {
 		sd, err := windows.SecurityDescriptorFromString("O:SYG:SYD:(A;;CCRC;;;" + dnsClientSID + ")")
 		if err != nil {
 			return err
@@ -343,8 +408,8 @@ func addLeakFilters(engine windows.Handle, tun winipcfg.LUID, dns, ipv4, ipv6 bo
 			key       *windows.GUID
 			localLink bool
 		}{
-			{&fwpmLayerALEAuthConnectV4, !ipv4},
-			{&fwpmLayerALEAuthConnectV6, !ipv6},
+			{&fwpmLayerALEAuthConnectV4, !block.ipv4},
+			{&fwpmLayerALEAuthConnectV6, !block.ipv6},
 		} {
 			if err := add(layer.key, "permit the DNS Client service through the TUN", 0, fwpActionPermit, 3, dnsClient, onTUN(&fwpmConditionIPLocalInterface), onTUN(&fwpmConditionIPNexthopInterface)); err != nil {
 				return err
@@ -367,7 +432,7 @@ func addLeakFilters(engine windows.Handle, tun winipcfg.LUID, dns, ipv4, ipv6 bo
 		matchType:      fwpMatchFlagsAllSet,
 		conditionValue: fwpValue0{typ: fwpUint32, value: fwpConditionFlagIsLoopback},
 	}
-	if ipv4 {
+	if block.ipv4 {
 		// DHCP keeps the addresses of the other interfaces, which Xray's own
 		// connections use.
 		dhcp := []fwpmFilterCondition0{
@@ -387,7 +452,7 @@ func addLeakFilters(engine windows.Handle, tun winipcfg.LUID, dns, ipv4, ipv6 bo
 			}
 		}
 	}
-	if ipv6 {
+	if block.ipv6 {
 		// Neighbor and multicast listener discovery, ICMPv6 130-137 and 143,
 		// whose type and code sit where the local and remote port are.
 		discovery := []fwpmFilterCondition0{condition(&fwpmConditionIPProtocol, fwpUint8, windows.IPPROTO_ICMPV6)}

proxy/tun/tun_windows_wfp_test.go

@@ -114,11 +114,38 @@ func TestLeakFiltersAccepted(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if err := addLeakFilters(engine, loopback, true, true, true); err != nil {
+	leaks, err := ExpandWfpBlockLeak([]string{"dns", "misconfigtun", "tcp/443"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	block := newLeakFilters(leaks, false, false)
+	block.dnsClient = true // whatever the Windows version
+	if err := addLeakFilters(engine, loopback, block); err != nil {
 		skipUnlessElevated(err)
 	}
 }
 
+func TestNewLeakFilters(t *testing.T) {
+	leaks, err := ExpandWfpBlockLeak([]string{"dns", "misconfigtun"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	block := newLeakFilters(leaks, true, false)
+	want := "udp/53, tcp/53, tcp/853, udp/853, IPv6"
+	if dnsClientUsesAnyPort() {
+		want = "udp/53, tcp/53, tcp/853, udp/853, windnsclient, IPv6"
+	}
+	if got := block.String(); got != want {
+		t.Errorf("String() = %q, want %q", got, want)
+	}
+	if !block.systemDNS() {
+		t.Error("systemDNS() = false with dns")
+	}
+	if block := newLeakFilters([]string{"tcp/853", "udp/853", "misconfigtun"}, true, true); block.String() != "tcp/853, udp/853" || block.systemDNS() {
+		t.Errorf("tcp/853, udp/853: %q, systemDNS() = %v", block.String(), block.systemDNS())
+	}
+}
+
 func TestDNSClientSID(t *testing.T) {
 	sid, _, _, err := windows.LookupSID("", `NT SERVICE\Dnscache`)
 	if err != nil {

proxy/tun/wfp_leak.go

@@ -0,0 +1,79 @@
+package tun
+
+import (
+	"slices"
+	"strconv"
+	"strings"
+
+	"github.com/xtls/xray-core/common/errors"
+)
+
+// dnsLeaks is what "dns" in autoSystemWfpBlockLeak stands for: DNS over UDP and
+// TCP, Windows' DNS Client service, which may also use other protocols and
+// ports, DNS over TLS, and DNS over QUIC.
+var dnsLeaks = []string{"udp/53", "tcp/53", "windnsclient", "tcp/853", "udp/853"}
+
+// leakPort is a "tcp/<port>" or "udp/<port>" value of autoSystemWfpBlockLeak:
+// connections to that port may only go through the TUN.
+type leakPort struct {
+	tcp  bool
+	port uint16
+}
+
+func (p leakPort) String() string {
+	if p.tcp {
+		return "tcp/" + strconv.Itoa(int(p.port))
+	}
+	return "udp/" + strconv.Itoa(int(p.port))
+}
+
+// parseLeakPort parses a lower case "tcp/<port>" or "udp/<port>" value.
+func parseLeakPort(value string) (leakPort, bool) {
+	protocol, port, ok := strings.Cut(value, "/")
+	if !ok || protocol != "tcp" && protocol != "udp" {
+		return leakPort{}, false
+	}
+	n, err := strconv.ParseUint(port, 10, 16)
+	if err != nil || n == 0 {
+		return leakPort{}, false
+	}
+	return leakPort{tcp: protocol == "tcp", port: uint16(n)}, true
+}
+
+// ExpandWfpBlockLeak checks the values of autoSystemWfpBlockLeak and returns
+// them in lower case, in order and without duplicates, with "dns" replaced by
+// what it stands for.
+func ExpandWfpBlockLeak(values []string) ([]string, error) {
+	var leaks []string
+	add := func(leak string) {
+		if !slices.Contains(leaks, leak) {
+			leaks = append(leaks, leak)
+		}
+	}
+	for _, value := range values {
+		switch value = strings.ToLower(value); value {
+		case "dns":
+			for _, leak := range dnsLeaks {
+				add(leak)
+			}
+		case "windnsclient", "misconfigtun":
+			add(value)
+		default:
+			port, ok := parseLeakPort(value)
+			if !ok {
+				return nil, errors.New("unknown autoSystemWfpBlockLeak value: ", value)
+			}
+			add(port.String())
+		}
+	}
+	return leaks, nil
+}
+
+// BlocksSystemDNS tells whether expanded autoSystemWfpBlockLeak values keep the
+// system's DNS (port 53, or Windows' DNS Client service) inside the TUN, which
+// then needs DNS servers of its own.
+func BlocksSystemDNS(leaks []string) bool {
+	return slices.ContainsFunc(leaks, func(leak string) bool {
+		return leak == "udp/53" || leak == "tcp/53" || leak == "windnsclient"
+	})
+}

proxy/tun/wfp_leak_test.go

@@ -0,0 +1,40 @@
+package tun
+
+import (
+	"slices"
+	"testing"
+)
+
+func TestExpandWfpBlockLeak(t *testing.T) {
+	for _, c := range []struct {
+		values    []string
+		leaks     []string
+		systemDNS bool
+	}{
+		{nil, nil, false},
+		{[]string{"dns"}, []string{"udp/53", "tcp/53", "windnsclient", "tcp/853", "udp/853"}, true},
+		{[]string{"DNS", "MisconfigTUN"}, []string{"udp/53", "tcp/53", "windnsclient", "tcp/853", "udp/853", "misconfigtun"}, true},
+		{[]string{"tcp/853", "dns", "TCP/0853"}, []string{"tcp/853", "udp/53", "tcp/53", "windnsclient", "udp/853"}, true},
+		{[]string{"tcp/853", "udp/853", "misconfigtun"}, []string{"tcp/853", "udp/853", "misconfigtun"}, false},
+		{[]string{"udp/65535", "tcp/1"}, []string{"udp/65535", "tcp/1"}, false},
+		{[]string{"tcp/53"}, []string{"tcp/53"}, true},
+		{[]string{"windnsclient"}, []string{"windnsclient"}, true},
+	} {
+		leaks, err := ExpandWfpBlockLeak(c.values)
+		if err != nil {
+			t.Errorf("%v: %v", c.values, err)
+			continue
+		}
+		if !slices.Equal(leaks, c.leaks) {
+			t.Errorf("%v: got %v, want %v", c.values, leaks, c.leaks)
+		}
+		if got := BlocksSystemDNS(leaks); got != c.systemDNS {
+			t.Errorf("%v: BlocksSystemDNS() = %v", c.values, got)
+		}
+	}
+	for _, value := range []string{"", "ip", "tcp", "tcp/", "tcp/0", "udp/65536", "tcp/-1", "tcp/+53", "tcp/53/1", "udp/abc", "icmp/1", "tcp:53", " dns"} {
+		if _, err := ExpandWfpBlockLeak([]string{value}); err == nil {
+			t.Errorf("%q was accepted", value)
+		}
+	}
+}

testing/scenarios/http_test.go

@@ -16,8 +16,10 @@ import (
 	"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/core"
+	"github.com/xtls/xray-core/proxy/dokodemo"
 	"github.com/xtls/xray-core/proxy/freedom"
 	v2http "github.com/xtls/xray-core/proxy/http"
 	v2httptest "github.com/xtls/xray-core/testing/servers/http"
@@ -377,3 +379,88 @@ func TestHttpBasicAuth(t *testing.T) {
 		}
 	}
 }
+
+// Server-first protocols (SMTP, FTP, MySQL) send nothing from the client until the server's
+// greeting arrives, so the HTTP outbound must not wait for a first payload before dialing.
+func TestHTTPOutboundServerFirst(t *testing.T) {
+	tcpServer := tcp.Server{
+		MsgProcessor: xor,
+		SendFirst:    []byte("send first"),
+	}
+	dest, err := tcpServer.Start()
+	common.Must(err)
+	defer tcpServer.Close()
+
+	serverPort := tcp.PickPort()
+	serverConfig := &core.Config{
+		Inbound: []*core.InboundHandlerConfig{
+			{
+				ReceiverSettings: serial.ToTypedMessage(&proxyman.ReceiverConfig{
+					PortList: &net.PortList{Range: []*net.PortRange{net.SinglePortRange(serverPort)}},
+					Listen:   net.NewIPOrDomain(net.LocalHostIP),
+				}),
+				ProxySettings: serial.ToTypedMessage(&v2http.ServerConfig{}),
+			},
+		},
+		Outbound: []*core.OutboundHandlerConfig{
+			{
+				ProxySettings: serial.ToTypedMessage(&freedom.Config{
+					FinalRules: []*freedom.FinalRuleConfig{{Action: freedom.RuleAction_Allow}},
+				}),
+			},
+		},
+	}
+
+	clientPort := tcp.PickPort()
+	clientConfig := &core.Config{
+		Inbound: []*core.InboundHandlerConfig{
+			{
+				ReceiverSettings: serial.ToTypedMessage(&proxyman.ReceiverConfig{
+					PortList: &net.PortList{Range: []*net.PortRange{net.SinglePortRange(clientPort)}},
+					Listen:   net.NewIPOrDomain(net.LocalHostIP),
+				}),
+				ProxySettings: serial.ToTypedMessage(&dokodemo.Config{
+					RewriteAddress:  net.NewIPOrDomain(dest.Address),
+					RewritePort:     uint32(dest.Port),
+					AllowedNetworks: []net.Network{net.Network_TCP},
+				}),
+			},
+		},
+		Outbound: []*core.OutboundHandlerConfig{
+			{
+				ProxySettings: serial.ToTypedMessage(&v2http.ClientConfig{
+					Server: &protocol.ServerEndpoint{
+						Address: net.NewIPOrDomain(net.LocalHostIP),
+						Port:    uint32(serverPort),
+					},
+				}),
+			},
+		},
+	}
+
+	servers, err := InitializeServerConfigs(serverConfig, clientConfig)
+	common.Must(err)
+	defer CloseAllServers(servers)
+
+	conn, err := net.DialTCP("tcp", nil, &net.TCPAddr{
+		IP:   []byte{127, 0, 0, 1},
+		Port: int(clientPort),
+	})
+	common.Must(err)
+	defer conn.Close()
+
+	common.Must(conn.SetReadDeadline(time.Now().Add(5 * time.Second)))
+	response := make([]byte, 1024)
+	nBytes, err := conn.Read(response)
+	if err != nil {
+		t.Fatal("no server greeting through HTTP outbound: ", err)
+	}
+	if string(response[:nBytes]) != "send first" {
+		t.Fatal("unexpected first response: ", string(response[:nBytes]))
+	}
+	common.Must(conn.SetReadDeadline(time.Time{}))
+
+	if err := testTCPConn2(conn, 1024, time.Second*5)(); err != nil {
+		t.Error(err)
+	}
+}

testing/scenarios/vless_test.go

@@ -3,6 +3,8 @@ package scenarios
 import (
 	"encoding/base64"
 	"encoding/hex"
+	"fmt"
+	"io"
 	"sync"
 	"testing"
 	"time"
@@ -20,6 +22,7 @@ import (
 	"github.com/xtls/xray-core/proxy/dokodemo"
 	"github.com/xtls/xray-core/proxy/freedom"
 	"github.com/xtls/xray-core/proxy/vless"
+	"github.com/xtls/xray-core/proxy/vless/encoding"
 	"github.com/xtls/xray-core/proxy/vless/inbound"
 	"github.com/xtls/xray-core/proxy/vless/outbound"
 	"github.com/xtls/xray-core/testing/servers/tcp"
@@ -657,3 +660,82 @@ func TestVlessRealityFingerprints(t *testing.T) {
 	}
 	wg.Wait()
 }
+
+// A blocked connection must be closed after blockDelay even while the client keeps it open and sends nothing.
+func TestVlessBlockDelay(t *testing.T) {
+	tcpServer := tcp.Server{
+		MsgProcessor: xor,
+	}
+	dest, err := tcpServer.Start()
+	common.Must(err)
+	defer tcpServer.Close()
+
+	for _, delay := range []uint64{0, 1} {
+		t.Run(fmt.Sprint("blockDelay=", delay), func(t *testing.T) {
+			userID := protocol.NewID(uuid.New())
+			serverPort := tcp.PickPort()
+			serverConfig := &core.Config{
+				Inbound: []*core.InboundHandlerConfig{
+					{
+						ReceiverSettings: serial.ToTypedMessage(&proxyman.ReceiverConfig{
+							PortList: &net.PortList{Range: []*net.PortRange{net.SinglePortRange(serverPort)}},
+							Listen:   net.NewIPOrDomain(net.LocalHostIP),
+						}),
+						ProxySettings: serial.ToTypedMessage(&inbound.Config{
+							Users: []*protocol.User{
+								{
+									Account: serial.ToTypedMessage(&vless.Account{
+										Id: userID.String(),
+									}),
+								},
+							},
+						}),
+					},
+				},
+				Outbound: []*core.OutboundHandlerConfig{
+					{
+						ProxySettings: serial.ToTypedMessage(&freedom.Config{
+							FinalRules: []*freedom.FinalRuleConfig{
+								{
+									Action:     freedom.RuleAction_Block,
+									BlockDelay: &freedom.Range{Min: delay, Max: delay},
+								},
+							},
+						}),
+					},
+				},
+			}
+
+			servers, err := InitializeServerConfigs(serverConfig)
+			common.Must(err)
+			defer CloseAllServers(servers)
+
+			conn, err := net.DialTCP("tcp", nil, &net.TCPAddr{
+				IP:   []byte{127, 0, 0, 1},
+				Port: int(serverPort),
+			})
+			common.Must(err)
+			defer conn.Close()
+
+			start := time.Now()
+			common.Must(encoding.EncodeRequestHeader(conn, &protocol.RequestHeader{
+				Version: encoding.Version,
+				User:    &protocol.MemoryUser{Account: &vless.MemoryAccount{ID: userID}},
+				Command: protocol.RequestCommandTCP,
+				Address: dest.Address,
+				Port:    dest.Port,
+			}, &encoding.Addons{}))
+
+			blockDelay := time.Duration(delay) * time.Second
+			common.Must(conn.SetReadDeadline(time.Now().Add(blockDelay + 5*time.Second)))
+			_, err = io.Copy(io.Discard, conn)
+			elapsed := time.Since(start)
+			if err, ok := err.(net.Error); ok && err.Timeout() {
+				t.Fatalf("connection is still open after %v", elapsed)
+			}
+			if elapsed < blockDelay {
+				t.Fatalf("connection is closed after %v, before blockDelay", elapsed)
+			}
+		})
+	}
+}

transport/internet/finalmask/filter/config.go

@@ -0,0 +1,63 @@
+package filter
+
+import (
+	"github.com/xtls/xray-core/common/geodata"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
+)
+
+func (c *Config) buildFilter() (*filter, error) {
+	if len(c.BlockedSourceIps) == 0 && len(c.AllowedSourceIps) == 0 {
+		return nil, nil
+	}
+	f := new(filter)
+	var err error
+	if len(c.BlockedSourceIps) > 0 {
+		f.blocked, err = geodata.IPReg.BuildIPMatcher(c.BlockedSourceIps)
+		if err != nil {
+			return nil, err
+		}
+	}
+	if len(c.AllowedSourceIps) > 0 {
+		f.allowed, err = geodata.IPReg.BuildIPMatcher(c.AllowedSourceIps)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return f, nil
+}
+
+func (c *Config) Listen(inner net.Listener) (net.Listener, error) {
+	f, err := c.buildFilter()
+	if err != nil {
+		return nil, err
+	}
+	if f == nil {
+		return inner, nil
+	}
+	return &listener{Listener: inner, filter: f}, nil
+}
+
+func (c *Config) WrapConnClient(conn net.Conn, dest *net.Destination, dialer *finalmask.Dialer) (net.Conn, error) {
+	return conn, nil
+}
+
+func (c *Config) WrapConnServer(conn net.Conn) (net.Conn, error) {
+	// TCP filtering is installed by Listen, before per-connection masks.
+	return conn, nil
+}
+
+func (c *Config) WrapPacketConnClient(conn net.PacketConn, dest *net.Destination, dialer *finalmask.Dialer) (net.PacketConn, error) {
+	return conn, nil
+}
+
+func (c *Config) WrapPacketConnServer(conn net.PacketConn, addr net.Addr, lc *finalmask.ListenConfig) (net.PacketConn, error) {
+	f, err := c.buildFilter()
+	if err != nil {
+		return nil, err
+	}
+	if f == nil {
+		return conn, nil
+	}
+	return &packetConn{PacketConn: conn, filter: f}, nil
+}

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

@@ -0,0 +1,136 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.36.11
+// 	protoc        v6.33.5
+// source: transport/internet/finalmask/filter/config.proto
+
+package filter
+
+import (
+	geodata "github.com/xtls/xray-core/common/geodata"
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+	unsafe "unsafe"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+type Config struct {
+	state            protoimpl.MessageState `protogen:"open.v1"`
+	BlockedSourceIps []*geodata.IPRule      `protobuf:"bytes,1,rep,name=blocked_source_ips,json=blockedSourceIps,proto3" json:"blocked_source_ips,omitempty"`
+	AllowedSourceIps []*geodata.IPRule      `protobuf:"bytes,2,rep,name=allowed_source_ips,json=allowedSourceIps,proto3" json:"allowed_source_ips,omitempty"`
+	unknownFields    protoimpl.UnknownFields
+	sizeCache        protoimpl.SizeCache
+}
+
+func (x *Config) Reset() {
+	*x = Config{}
+	mi := &file_transport_internet_finalmask_filter_config_proto_msgTypes[0]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *Config) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Config) ProtoMessage() {}
+
+func (x *Config) ProtoReflect() protoreflect.Message {
+	mi := &file_transport_internet_finalmask_filter_config_proto_msgTypes[0]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use Config.ProtoReflect.Descriptor instead.
+func (*Config) Descriptor() ([]byte, []int) {
+	return file_transport_internet_finalmask_filter_config_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *Config) GetBlockedSourceIps() []*geodata.IPRule {
+	if x != nil {
+		return x.BlockedSourceIps
+	}
+	return nil
+}
+
+func (x *Config) GetAllowedSourceIps() []*geodata.IPRule {
+	if x != nil {
+		return x.AllowedSourceIps
+	}
+	return nil
+}
+
+var File_transport_internet_finalmask_filter_config_proto protoreflect.FileDescriptor
+
+const file_transport_internet_finalmask_filter_config_proto_rawDesc = "" +
+	"\n" +
+	"0transport/internet/finalmask/filter/config.proto\x12(xray.transport.internet.finalmask.filter\x1a\x1bcommon/geodata/geodat.proto\"\x9e\x01\n" +
+	"\x06Config\x12I\n" +
+	"\x12blocked_source_ips\x18\x01 \x03(\v2\x1b.xray.common.geodata.IPRuleR\x10blockedSourceIps\x12I\n" +
+	"\x12allowed_source_ips\x18\x02 \x03(\v2\x1b.xray.common.geodata.IPRuleR\x10allowedSourceIpsB\x9a\x01\n" +
+	",com.xray.transport.internet.finalmask.filterP\x01Z=github.com/xtls/xray-core/transport/internet/finalmask/filter\xaa\x02(Xray.Transport.Internet.Finalmask.Filterb\x06proto3"
+
+var (
+	file_transport_internet_finalmask_filter_config_proto_rawDescOnce sync.Once
+	file_transport_internet_finalmask_filter_config_proto_rawDescData []byte
+)
+
+func file_transport_internet_finalmask_filter_config_proto_rawDescGZIP() []byte {
+	file_transport_internet_finalmask_filter_config_proto_rawDescOnce.Do(func() {
+		file_transport_internet_finalmask_filter_config_proto_rawDescData = protoimpl.X.CompressGZIP(unsafe.Slice(unsafe.StringData(file_transport_internet_finalmask_filter_config_proto_rawDesc), len(file_transport_internet_finalmask_filter_config_proto_rawDesc)))
+	})
+	return file_transport_internet_finalmask_filter_config_proto_rawDescData
+}
+
+var file_transport_internet_finalmask_filter_config_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
+var file_transport_internet_finalmask_filter_config_proto_goTypes = []any{
+	(*Config)(nil),         // 0: xray.transport.internet.finalmask.filter.Config
+	(*geodata.IPRule)(nil), // 1: xray.common.geodata.IPRule
+}
+var file_transport_internet_finalmask_filter_config_proto_depIdxs = []int32{
+	1, // 0: xray.transport.internet.finalmask.filter.Config.blocked_source_ips:type_name -> xray.common.geodata.IPRule
+	1, // 1: xray.transport.internet.finalmask.filter.Config.allowed_source_ips:type_name -> xray.common.geodata.IPRule
+	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_transport_internet_finalmask_filter_config_proto_init() }
+func file_transport_internet_finalmask_filter_config_proto_init() {
+	if File_transport_internet_finalmask_filter_config_proto != nil {
+		return
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: unsafe.Slice(unsafe.StringData(file_transport_internet_finalmask_filter_config_proto_rawDesc), len(file_transport_internet_finalmask_filter_config_proto_rawDesc)),
+			NumEnums:      0,
+			NumMessages:   1,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_transport_internet_finalmask_filter_config_proto_goTypes,
+		DependencyIndexes: file_transport_internet_finalmask_filter_config_proto_depIdxs,
+		MessageInfos:      file_transport_internet_finalmask_filter_config_proto_msgTypes,
+	}.Build()
+	File_transport_internet_finalmask_filter_config_proto = out.File
+	file_transport_internet_finalmask_filter_config_proto_goTypes = nil
+	file_transport_internet_finalmask_filter_config_proto_depIdxs = nil
+}

transport/internet/finalmask/filter/config.proto

@@ -0,0 +1,14 @@
+syntax = "proto3";
+
+package xray.transport.internet.finalmask.filter;
+option csharp_namespace = "Xray.Transport.Internet.Finalmask.Filter";
+option go_package = "github.com/xtls/xray-core/transport/internet/finalmask/filter";
+option java_package = "com.xray.transport.internet.finalmask.filter";
+option java_multiple_files = true;
+
+import "common/geodata/geodat.proto";
+
+message Config {
+  repeated xray.common.geodata.IPRule blocked_source_ips = 1;
+  repeated xray.common.geodata.IPRule allowed_source_ips = 2;
+}

transport/internet/finalmask/filter/filter.go

@@ -0,0 +1,69 @@
+package filter
+
+import (
+	"github.com/xtls/xray-core/common/geodata"
+	"github.com/xtls/xray-core/common/net"
+)
+
+type listener struct {
+	net.Listener
+	filter *filter
+}
+
+// Accept filters connections after the TCP handshake and before higher-level processing.
+func (l *listener) Accept() (net.Conn, error) {
+	for {
+		conn, err := l.Listener.Accept()
+		if err != nil {
+			return nil, err
+		}
+		if l.filter.rejects(conn.RemoteAddr()) {
+			conn.Close()
+			continue
+		}
+		return conn, nil
+	}
+}
+
+type packetConn struct {
+	net.PacketConn
+	filter *filter
+}
+
+func (c *packetConn) ReadFrom(p []byte) (int, net.Addr, error) {
+	for {
+		n, addr, err := c.PacketConn.ReadFrom(p)
+		// Reads may return both data and an error; filter the data first.
+		if c.filter.rejects(addr) {
+			if err != nil {
+				return 0, nil, err
+			}
+			continue
+		}
+		return n, addr, err
+	}
+}
+
+type filter struct {
+	blocked geodata.IPMatcher
+	allowed geodata.IPMatcher
+}
+
+func (f *filter) rejects(addr net.Addr) bool {
+	var ip net.IP
+	switch addr := addr.(type) {
+	case *net.TCPAddr:
+		ip = addr.IP
+	case *net.UDPAddr:
+		ip = addr.IP
+	case *net.IPAddr:
+		ip = addr.IP
+	default:
+		// Unknown sources cannot satisfy an allowlist.
+		return f.allowed != nil
+	}
+	if f.blocked != nil && f.blocked.Match(ip) {
+		return true
+	}
+	return f.allowed != nil && !f.allowed.Match(ip)
+}

transport/internet/finalmask/filter/filter_test.go

@@ -0,0 +1,311 @@
+package filter
+
+import (
+	"context"
+	"errors"
+	"io"
+	"net"
+	"testing"
+	"time"
+
+	"github.com/pires/go-proxyproto"
+	"github.com/xtls/xray-core/common/geodata"
+	xnet "github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
+)
+
+func TestTCPFilterBeforeOtherMasks(t *testing.T) {
+	for _, policy := range testPolicies(t) {
+		t.Run(policy.name, func(t *testing.T) {
+			blocked4 := sourceConn("192.0.2.1")
+			blocked6 := sourceConn("2001:db8::1")
+			unknown := &testConn{addr: &net.UnixAddr{Name: "filter.sock", Net: "unix"}}
+			missing := new(testConn)
+			allowed := sourceConn("198.51.100.1")
+			allowed6 := sourceConn("2001:db8:1::1")
+			raw := &testListener{conns: []net.Conn{blocked4, blocked6, unknown, missing, allowed, allowed6}}
+			spy := new(recordMask)
+			fm := finalmask.NewFinalMask([]finalmask.TCPMask{spy, policy.config}, nil, nil,
+				func(context.Context, net.Addr) (net.Listener, error) { return raw, nil }, nil, nil)
+			l, err := fm.Listen(context.Background(), &net.TCPAddr{})
+			if err != nil {
+				t.Fatal(err)
+			}
+			defer l.Close()
+			whitelist := len(policy.config.AllowedSourceIps) > 0
+			want := []net.Conn{allowed, allowed6}
+			if !whitelist {
+				want = append([]net.Conn{unknown, missing}, want...)
+			}
+			for _, expected := range want {
+				if got, err := l.Accept(); err != nil || got != expected {
+					t.Fatalf("Accept() = (%v, %v), want %v", got, err, expected)
+				}
+			}
+			// Fake sockets panic on Read or Write. Rejection must not require handshake data.
+			if !blocked4.closed || !blocked6.closed || unknown.closed != whitelist || missing.closed != whitelist || allowed.closed || allowed6.closed || raw.closed {
+				t.Fatal("filter did not close only the blocked connections")
+			}
+			if len(spy.seen) != len(want) {
+				t.Fatal("blocked connections reached the next mask")
+			}
+			for i, conn := range spy.seen {
+				if conn != want[i] {
+					t.Fatal("unexpected connection reached the next mask")
+				}
+			}
+			if conn, err := l.Accept(); conn != nil || !errors.Is(err, io.EOF) {
+				t.Fatalf("listener error was not propagated: (%v, %v)", conn, err)
+			}
+		})
+	}
+}
+
+func TestTCPFilterUsesProxyHeader(t *testing.T) {
+	for _, test := range []struct {
+		name, peer, reported string
+		blocked              bool
+	}{
+		{"blocked_header", "198.51.100.1", "192.0.2.1", true},
+		{"allowed_header", "192.0.2.1", "198.51.100.1", false},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			server, client := net.Pipe()
+			defer server.Close()
+			defer client.Close()
+			if err := server.SetDeadline(time.Now().Add(5 * time.Second)); err != nil {
+				t.Fatal(err)
+			}
+			peer := sourceConn(test.peer)
+			peer.Conn = server
+			conn := proxyproto.NewConn(peer)
+			next := sourceConn("198.51.100.2")
+			l, err := testConfig(t, "192.0.2.0/24").Listen(&testListener{conns: []net.Conn{conn, next}})
+			if err != nil {
+				t.Fatal(err)
+			}
+			defer l.Close()
+			written := make(chan error, 1)
+			go func() {
+				_, err := client.Write([]byte("PROXY TCP4 " + test.reported + " 203.0.113.1 1234 443\r\n"))
+				written <- err
+			}()
+			got, err := l.Accept()
+			if err != nil {
+				t.Fatal(err)
+			}
+			if err := <-written; err != nil {
+				t.Fatal(err)
+			}
+			var want net.Conn = conn
+			if test.blocked {
+				want = next
+			}
+			if got != want || peer.closed != test.blocked {
+				t.Fatal("filter did not follow the address supplied by PROXY protocol")
+			}
+		})
+	}
+}
+
+func TestUDPFilter(t *testing.T) {
+	for _, policy := range testPolicies(t) {
+		t.Run(policy.name, func(t *testing.T) {
+			allowed := &net.UDPAddr{IP: net.ParseIP("198.51.100.1"), Port: 1234}
+			allowed6 := &net.UDPAddr{IP: net.ParseIP("2001:db8:1::1"), Port: 1234}
+			unknown := datagram{data: []byte("unknown"), addr: &net.UnixAddr{Name: "filter.sock", Net: "unixgram"}}
+			missing := datagram{data: []byte("missing address")}
+			raw := &testPacketConn{reads: []datagram{
+				{data: []byte("blocked"), addr: &net.UDPAddr{IP: net.ParseIP("192.0.2.1"), Port: 1234}},
+				{addr: &net.UDPAddr{IP: net.ParseIP("2001:db8::1"), Port: 1234}},
+				unknown,
+				missing,
+				{addr: allowed},
+				{data: []byte("allowed"), addr: allowed},
+				{data: []byte("allowed6"), addr: allowed6},
+				{data: []byte("blocked again"), addr: &net.UDPAddr{IP: net.ParseIP("192.0.2.2"), Port: 1234}},
+			}}
+			fm := finalmask.NewFinalMask(nil, []finalmask.UDPMask{policy.config}, nil, nil, nil,
+				func(context.Context, net.Addr) (net.PacketConn, error) { return raw, nil })
+			conn, err := fm.ListenPacket(context.Background(), &net.UDPAddr{})
+			if err != nil {
+				t.Fatal(err)
+			}
+			defer conn.Close()
+			buf := make([]byte, 64)
+			if len(policy.config.AllowedSourceIps) == 0 {
+				for _, expected := range []datagram{unknown, missing} {
+					n, addr, err := conn.ReadFrom(buf)
+					if err != nil || addr != expected.addr || string(buf[:n]) != string(expected.data) {
+						t.Fatalf("unknown source was not allowed by blacklist: (%q, %v, %v)", buf[:n], addr, err)
+					}
+				}
+			}
+			if n, addr, err := conn.ReadFrom(buf); n != 0 || addr != allowed || err != nil {
+				t.Fatalf("zero-length allowed datagram was lost: (%d, %v, %v)", n, addr, err)
+			}
+			n, addr, err := conn.ReadFrom(buf)
+			if err != nil || addr != allowed || string(buf[:n]) != "allowed" {
+				t.Fatalf("ReadFrom() = (%q, %v, %v)", buf[:n], addr, err)
+			}
+			n, addr, err = conn.ReadFrom(buf)
+			if err != nil || addr != allowed6 || string(buf[:n]) != "allowed6" {
+				t.Fatalf("IPv6 ReadFrom() = (%q, %v, %v)", buf[:n], addr, err)
+			}
+			if _, _, err := conn.ReadFrom(buf); !errors.Is(err, io.EOF) {
+				t.Fatalf("underlying read error was not propagated: %v", err)
+			}
+			if raw.closed {
+				t.Fatal("dropping a packet closed the shared UDP socket")
+			}
+		})
+	}
+}
+
+func TestEmptyFilter(t *testing.T) {
+	for _, empty := range []*Config{{}, {AllowedSourceIps: []*geodata.IPRule{}}} {
+		rawListener := new(testListener)
+		rawPacket := new(testPacketConn)
+		if l, err := empty.Listen(rawListener); err != nil || l != rawListener {
+			t.Fatal("an empty TCP filter should preserve the listener")
+		}
+		if conn, err := empty.WrapPacketConnServer(rawPacket, nil, nil); err != nil || conn != rawPacket {
+			t.Fatal("an empty UDP filter should preserve the socket")
+		}
+	}
+}
+
+func TestUDPFilterReadError(t *testing.T) {
+	for _, policy := range testPolicies(t) {
+		t.Run(policy.name, func(t *testing.T) {
+			for _, test := range []struct {
+				name    string
+				source  net.Addr
+				blocked bool
+			}{
+				{"blocked", &net.UDPAddr{IP: net.ParseIP("192.0.2.1")}, true},
+				{"allowed", &net.UDPAddr{IP: net.ParseIP("198.51.100.1")}, false},
+				{"missing address", nil, len(policy.config.AllowedSourceIps) > 0},
+				{"unknown address", &net.UnixAddr{Name: "filter.sock", Net: "unixgram"}, len(policy.config.AllowedSourceIps) > 0},
+			} {
+				t.Run(test.name, func(t *testing.T) {
+					source := test.source
+					raw := &testPacketConn{reads: []datagram{{data: []byte("partial"), addr: source, err: io.ErrShortBuffer}}}
+					conn, err := policy.config.WrapPacketConnServer(raw, nil, nil)
+					if err != nil {
+						t.Fatal(err)
+					}
+					buf := make([]byte, 32)
+					n, addr, err := conn.ReadFrom(buf)
+					if !errors.Is(err, io.ErrShortBuffer) {
+						t.Fatalf("read error was not preserved: %v", err)
+					}
+					if test.blocked {
+						if n != 0 || addr != nil {
+							t.Fatal("partial data from a blocked source was returned with an error")
+						}
+					} else if n != 7 || addr != source || string(buf[:n]) != "partial" {
+						t.Fatal("partial data from an unblocked source was changed")
+					}
+				})
+			}
+		})
+	}
+}
+
+func testPolicies(t *testing.T) []struct {
+	name   string
+	config *Config
+} {
+	t.Helper()
+	blocked := testConfig(t, "192.0.2.0/24", "2001:db8::/48").BlockedSourceIps
+	allowed := testConfig(t, "198.51.100.0/24", "2001:db8:1::/48").BlockedSourceIps
+	broader := testConfig(t, "192.0.2.0/24", "198.51.100.0/24", "2001:db8::/32").BlockedSourceIps
+	return []struct {
+		name   string
+		config *Config
+	}{
+		{"blacklist", &Config{BlockedSourceIps: blocked}},
+		{"whitelist", &Config{AllowedSourceIps: allowed}},
+		{"both", &Config{BlockedSourceIps: blocked, AllowedSourceIps: broader}},
+	}
+}
+
+func testConfig(t *testing.T, entries ...string) *Config {
+	t.Helper()
+	rules, err := geodata.ParseIPRules(entries)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return &Config{BlockedSourceIps: rules}
+}
+
+type testConn struct {
+	net.Conn
+	addr   net.Addr
+	closed bool
+}
+
+func sourceConn(ip string) *testConn {
+	return &testConn{addr: &net.TCPAddr{IP: net.ParseIP(ip), Port: 1234}}
+}
+
+func (c *testConn) RemoteAddr() net.Addr { return c.addr }
+func (c *testConn) Close() error {
+	c.closed = true
+	if c.Conn != nil {
+		return c.Conn.Close()
+	}
+	return nil
+}
+
+type testListener struct {
+	net.Listener
+	conns  []net.Conn
+	closed bool
+}
+
+func (l *testListener) Accept() (net.Conn, error) {
+	if len(l.conns) == 0 {
+		return nil, io.EOF
+	}
+	conn := l.conns[0]
+	l.conns = l.conns[1:]
+	return conn, nil
+}
+
+func (l *testListener) Close() error { l.closed = true; return nil }
+
+type datagram struct {
+	data []byte
+	addr net.Addr
+	err  error
+}
+
+type testPacketConn struct {
+	net.PacketConn
+	reads  []datagram
+	closed bool
+}
+
+func (c *testPacketConn) ReadFrom(p []byte) (int, net.Addr, error) {
+	if len(c.reads) == 0 {
+		return 0, nil, io.EOF
+	}
+	packet := c.reads[0]
+	c.reads = c.reads[1:]
+	return copy(p, packet.data), packet.addr, packet.err
+}
+
+func (c *testPacketConn) Close() error { c.closed = true; return nil }
+
+type recordMask struct{ seen []net.Conn }
+
+func (m *recordMask) WrapConnClient(c net.Conn, _ *xnet.Destination, _ *finalmask.Dialer) (net.Conn, error) {
+	return c, nil
+}
+
+func (m *recordMask) WrapConnServer(c net.Conn) (net.Conn, error) {
+	m.seen = append(m.seen, c)
+	return c, nil
+}

transport/internet/reality/config.go

@@ -68,7 +68,7 @@ func KeyLogWriterFromConfig(c *Config) io.Writer {
 		return nil
 	}
 
-	writer, err := os.OpenFile(c.MasterKeyLog, os.O_CREATE|os.O_RDWR|os.O_APPEND, 0o644)
+	writer, err := os.OpenFile(c.MasterKeyLog, os.O_CREATE|os.O_RDWR|os.O_APPEND, 0o600)
 	if err != nil {
 		errors.LogErrorInner(context.Background(), err, "failed to open ", c.MasterKeyLog, " as master key log")
 	}

transport/internet/sockopt_darwin.go

@@ -114,13 +114,13 @@ func applyOutboundSocketOptions(network string, address string, fd uintptr, conf
 
 		if config.TcpKeepAliveIdle > 0 || config.TcpKeepAliveInterval > 0 {
 			if config.TcpKeepAliveIdle > 0 {
-				if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, unix.TCP_KEEPALIVE, int(config.TcpKeepAliveInterval)); err != nil {
-					return errors.New("failed to set TCP_KEEPINTVL", err)
+				if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, unix.TCP_KEEPALIVE, int(config.TcpKeepAliveIdle)); err != nil {
+					return errors.New("failed to set TCP_KEEPALIVE", err)
 				}
 			}
 			if config.TcpKeepAliveInterval > 0 {
-				if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, sysTCP_KEEPINTVL, int(config.TcpKeepAliveIdle)); err != nil {
-					return errors.New("failed to set TCP_KEEPIDLE", err)
+				if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, sysTCP_KEEPINTVL, int(config.TcpKeepAliveInterval)); err != nil {
+					return errors.New("failed to set TCP_KEEPINTVL", err)
 				}
 			}
 			if err := unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_KEEPALIVE, 1); err != nil {
@@ -204,13 +204,13 @@ func applyInboundSocketOptions(network string, fd uintptr, config *SocketConfig)
 
 		if config.TcpKeepAliveIdle > 0 || config.TcpKeepAliveInterval > 0 {
 			if config.TcpKeepAliveIdle > 0 {
-				if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, unix.TCP_KEEPALIVE, int(config.TcpKeepAliveInterval)); err != nil {
-					return errors.New("failed to set TCP_KEEPINTVL", err)
+				if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, unix.TCP_KEEPALIVE, int(config.TcpKeepAliveIdle)); err != nil {
+					return errors.New("failed to set TCP_KEEPALIVE", err)
 				}
 			}
 			if config.TcpKeepAliveInterval > 0 {
-				if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, sysTCP_KEEPINTVL, int(config.TcpKeepAliveIdle)); err != nil {
-					return errors.New("failed to set TCP_KEEPIDLE", err)
+				if err := unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, sysTCP_KEEPINTVL, int(config.TcpKeepAliveInterval)); err != nil {
+					return errors.New("failed to set TCP_KEEPINTVL", err)
 				}
 			}
 			if err := unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_KEEPALIVE, 1); err != nil {

transport/internet/system_dialer.go

@@ -2,6 +2,8 @@ package internet
 
 import (
 	"context"
+	go_errors "errors"
+	"runtime"
 	"sync"
 	"syscall"
 	"time"
@@ -69,9 +71,10 @@ func (d *DefaultSystemDialer) Dial(ctx context.Context, src net.Address, dest ne
 		}
 		var lc net.ListenConfig
 		if sockopt != nil || len(Controllers) > 0 {
-			lc.Control = func(network, address string, c syscall.RawConn) error {
+			lc.Control = func(network, _ string, c syscall.RawConn) error {
+				// ListenPacket supplies a local address; dialer controllers need the destination.
 				for _, ctl := range Controllers {
-					if err := ctl(network, address, c); err != nil {
+					if err := ctl(network, destAddr.String(), c); err != nil {
 						return errors.New("failed to apply external controller").Base(err)
 					}
 				}
@@ -91,6 +94,16 @@ func (d *DefaultSystemDialer) Dial(ctx context.Context, src net.Address, dest ne
 			}
 		}
 		packetConn, err := lc.ListenPacket(ctx, srcAddr.Network(), srcAddr.String())
+		var bindErr *BindError
+		if err != nil && runtime.GOOS == "windows" && go_errors.As(err, &bindErr) {
+			// Keep dual-stack UDP when possible. If the interface cannot bind both
+			// families, retry a socket that cannot send on the unbound family.
+			network := "udp6"
+			if destAddr.IP.To4() != nil {
+				network = "udp4"
+			}
+			packetConn, err = lc.ListenPacket(ctx, network, srcAddr.String())
+		}
 		if err != nil {
 			return nil, err
 		}
@@ -197,6 +210,7 @@ func UseAlternativeSystemDialer(dialer SystemDialer) {
 
 // RegisterDialerController adds a controller to the effective system dialer.
 // The controller can be used to operate on file descriptors before they are put into use.
+// It receives the network and resolved remote address, as in net.Dialer.Control.
 // It only works when effective dialer is the default dialer.
 //
 // xray:api:beta

transport/internet/system_dialer_windows_test.go

@@ -0,0 +1,63 @@
+package internet_test
+
+import (
+	"context"
+	"errors"
+	"slices"
+	"syscall"
+	"testing"
+
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet"
+	"golang.org/x/sys/windows"
+)
+
+// TestDialUDPBindFallback checks that a UDP dial whose dual-stack socket
+// cannot be bound to both IP versions, as on an interface without one of
+// them, moves to a socket of the destination's version only, and still
+// fails when that one cannot be bound either.
+func TestDialUDPBindFallback(t *testing.T) {
+	for _, c := range []struct {
+		dest   string
+		reject []string // the kinds of socket that cannot be bound
+		tried  []string // the kinds of socket tried, in order
+		ok     bool
+	}{
+		{"127.0.0.1", nil, []string{"dual"}, true},
+		{"127.0.0.1", []string{"dual"}, []string{"dual", "udp4"}, true},
+		{"::1", []string{"dual"}, []string{"dual", "udp6"}, true},
+		{"127.0.0.1", []string{"dual", "udp4"}, []string{"dual", "udp4"}, false},
+	} {
+		var tried []string
+		internet.ControllersLock.Lock()
+		saved := internet.Controllers
+		internet.Controllers = []func(string, string, syscall.RawConn) error{func(network, _ string, rc syscall.RawConn) error {
+			kind := network
+			if network == "udp6" {
+				rc.Control(func(fd uintptr) {
+					if v6only, _ := windows.GetsockoptInt(windows.Handle(fd), windows.IPPROTO_IPV6, windows.IPV6_V6ONLY); v6only == 0 {
+						kind = "dual"
+					}
+				})
+			}
+			tried = append(tried, kind)
+			if slices.Contains(c.reject, kind) {
+				return internet.NewBindError(errors.New("cannot bind " + kind))
+			}
+			return nil
+		}}
+		internet.ControllersLock.Unlock()
+
+		conn, err := internet.DialSystem(context.Background(), net.UDPDestination(net.ParseAddress(c.dest), 53), nil)
+		if conn != nil {
+			conn.Close()
+		}
+		internet.ControllersLock.Lock()
+		internet.Controllers = saved
+		internet.ControllersLock.Unlock()
+
+		if (err == nil) != c.ok || !slices.Equal(tried, c.tried) {
+			t.Errorf("%s rejecting %v: tried %v, err %v", c.dest, c.reject, tried, err)
+		}
+	}
+}

transport/internet/tls/config.go

@@ -466,7 +466,7 @@ func (c *Config) GetTLSConfig(opts ...Option) *tls.Config {
 	}
 
 	if len(c.MasterKeyLog) > 0 && c.MasterKeyLog != "none" {
-		writer, err := os.OpenFile(c.MasterKeyLog, os.O_CREATE|os.O_RDWR|os.O_APPEND, 0o644)
+		writer, err := os.OpenFile(c.MasterKeyLog, os.O_CREATE|os.O_RDWR|os.O_APPEND, 0o600)
 		if err != nil {
 			errors.LogErrorInner(context.Background(), err, "failed to open ", c.MasterKeyLog, " as master key log")
 		} else {

transport/internet/websocket/connection.go

@@ -46,6 +46,12 @@ func (c *connection) Read(b []byte) (int, error) {
 	for {
 		reader, err := c.getReader()
 		if err != nil {
+			// A close frame with a normal status (1000) or no status (1005) ends
+			// the byte stream the same way a FIN does, so report io.EOF instead
+			// of an error. Other close codes keep their error semantics.
+			if websocket.IsCloseError(err, websocket.CloseNormalClosure, websocket.CloseNoStatusReceived) {
+				return 0, io.EOF
+			}
 			return 0, err
 		}
 

transport/internet/xdrive/client.go

@@ -2,14 +2,25 @@ package xdrive
 
 import (
 	"context"
+	gotls "crypto/tls"
 	"io"
 	"net/http"
+	"reflect"
+	"runtime"
+	"slices"
 	"sync"
 	"time"
 
+	"github.com/apernet/quic-go"
+	"github.com/apernet/quic-go/http3"
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/common/net/cnc"
+	"github.com/xtls/xray-core/common/utils"
 	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/hysteria/congestion"
+	"github.com/xtls/xray-core/transport/internet/hysteria/congestion/bbr"
+	"github.com/xtls/xray-core/transport/internet/splithttp"
 	"github.com/xtls/xray-core/transport/internet/tls"
 )
 
@@ -39,6 +50,10 @@ func (t *serviceTransport) RoundTrip(r *http.Request) (*http.Response, error) {
 		cancel(nil)
 	}
 	r = r.WithContext(ctx)
+	// the headers of chrome as with XHTTP and DoH, net/http and http3 would send
+	// their own user agent after a hello of chrome
+	r.Header = r.Header.Clone()
+	utils.TryDefaultHeadersWith(r.Header, "fetch")
 	if r.Body != nil && r.Body != http.NoBody {
 		r.Body = &progressBody{ReadCloser: r.Body, alive: alive}
 	}
@@ -104,25 +119,40 @@ func (b *progressBody) Close() error {
 }
 
 // newServiceClient returns a client whose requests end after stall without
-// progress, see serviceTransport.RoundTrip
-func newServiceClient(streamSettings *internet.MemoryStreamConfig, stall time.Duration, maxConns int) *http.Client {
+// progress, see serviceTransport.RoundTrip, and whose connections close when
+// connCtx is done. Clients that share h1Hosts share which hosts answer over h1
+func newServiceClient(connCtx context.Context, h1Hosts *sync.Map, streamSettings *internet.MemoryStreamConfig, stall time.Duration, maxConns int) *http.Client {
 	var (
 		tlsConfig *tls.Config
 		sockopt   *internet.SocketConfig
 		fronting  *net.Destination
+		keepAlive = net.ChromeH2KeepAlivePeriod
+		// h3 keeps alive only when asked to, see below
+		h3KeepAlive time.Duration
 	)
 	if streamSettings != nil {
 		tlsConfig = tls.ConfigFromStreamSettings(streamSettings)
 		sockopt = streamSettings.SocketSettings
 		fronting = streamSettings.Destination
+		if config, ok := streamSettings.ProtocolSettings.(*Config); ok && config.Xmux != nil {
+			switch period := config.Xmux.HKeepAlivePeriod; {
+			case period > 0:
+				keepAlive = time.Duration(period) * time.Second
+				h3KeepAlive = keepAlive
+			case period < 0:
+				keepAlive = 0
+			}
+		}
 	}
 	if tlsConfig == nil {
 		tlsConfig = &tls.Config{}
 	}
 	fingerprint := tls.GetFingerprint(tlsConfig.Fingerprint)
 
-	dial := func(ctx context.Context, addr string) (net.Conn, net.Destination, error) {
-		host, err := net.ParseDestination("tcp:" + addr)
+	// fronting takes only the address and port, the network stays that of the
+	// dial, which is UDP for h3 though the destination is built as TCP
+	dial := func(ctx context.Context, network, addr string) (net.Conn, net.Destination, error) {
+		host, err := net.ParseDestination(network + ":" + addr)
 		if err != nil {
 			return nil, host, errors.New("bad address: ", addr).Base(err)
 		}
@@ -136,25 +166,36 @@ func newServiceClient(streamSettings *internet.MemoryStreamConfig, stall time.Du
 		}
 
 		var conn net.Conn
-		if streamSettings.FinalMask != nil {
-			conn, err = streamSettings.FinalMask.DialTCP(ctx, target)
-		} else {
+		switch {
+		case streamSettings.FinalMask == nil:
 			conn, err = internet.DialSystem(ctx, target, sockopt)
+		case target.Network == net.Network_UDP:
+			conn, err = streamSettings.FinalMask.DialUDP(ctx, target)
+		default:
+			conn, err = streamSettings.FinalMask.DialTCP(ctx, target)
 		}
 		if err != nil {
 			return nil, host, errors.New("failed to dial to dest").Base(err)
 		}
-		return conn, host, nil
+		// h3 closes its QUIC connection instead, as the server never hears of a UDP
+		// socket that closes
+		if network == "udp" {
+			return conn, host, nil
+		}
+		// CloseIdleConnections leaves an h2 connection open while a stream just
+		// canceled has not left it yet
+		stop := context.AfterFunc(connCtx, func() { conn.Close() })
+		return &ctxConn{Conn: conn, stop: stop}, host, nil
 	}
 
 	dialPlain := func(ctx context.Context, network, addr string) (net.Conn, error) {
-		conn, _, err := dial(ctx, addr)
+		conn, _, err := dial(ctx, "tcp", addr)
 		return conn, err
 	}
 
 	// http.Transport picks h2 or h1 by the ALPN in the ConnectionState of the conn
 	dialTLS := func(ctx context.Context, network, addr string) (net.Conn, error) {
-		conn, host, err := dial(ctx, addr)
+		conn, host, err := dial(ctx, "tcp", addr)
 		if err != nil {
 			return nil, err
 		}
@@ -185,7 +226,86 @@ func newServiceClient(streamSettings *internet.MemoryStreamConfig, stall time.Du
 			MaxIdleConns:        maxConns,
 			MaxIdleConnsPerHost: maxConns,
 			MaxConnsPerHost:     connsPerHost,
-			HTTP2:               &http.HTTP2Config{SendPingTimeout: net.ChromeH2KeepAlivePeriod},
+			HTTP2:               &http.HTTP2Config{SendPingTimeout: keepAlive},
+		}
+	}
+
+	var https http.RoundTripper = &secureTransport{h2: secure(1), h1: secure(maxConns), h1Hosts: h1Hosts}
+	// no server offers h3 by ALPN over TCP, so it is used only when asked for alone
+	if slices.Equal(tlsConfig.NextProtocol, []string{"h3"}) {
+		quicParams := streamSettings.QuicParams
+		if quicParams == nil {
+			quicParams = &internet.QuicParams{BbrProfile: string(bbr.ProfileStandard)}
+		}
+		// the defaults are those of quic-go, with no keepalive unless asked for, as
+		// in DoH: http3 never closes a connection that is idle or that it dropped
+		// after an error, so only the idle timeout or the end of connCtx ends it
+		quicConfig := &quic.Config{
+			InitialStreamReceiveWindow:     quicParams.InitStreamReceiveWindow,
+			MaxStreamReceiveWindow:         quicParams.MaxStreamReceiveWindow,
+			InitialConnectionReceiveWindow: quicParams.InitConnReceiveWindow,
+			MaxConnectionReceiveWindow:     quicParams.MaxConnReceiveWindow,
+			MaxIdleTimeout:                 time.Duration(quicParams.MaxIdleTimeout) * time.Second,
+			KeepAlivePeriod:                time.Duration(quicParams.KeepAlivePeriod) * time.Second,
+			MaxIncomingStreams:             quicParams.MaxIncomingStreams,
+			DisablePathMTUDiscovery:        quicParams.DisablePathMtuDiscovery || (runtime.GOOS != "linux" && runtime.GOOS != "windows" && runtime.GOOS != "darwin"),
+			ChromeParrot:                   !quicParams.DisableChromeParrot,
+		}
+		if quicConfig.KeepAlivePeriod == 0 {
+			quicConfig.KeepAlivePeriod = h3KeepAlive
+		}
+
+		https = &http3.Transport{
+			QUICConfig: quicConfig,
+			Dial: func(ctx context.Context, addr string, _ *gotls.Config, cfg *quic.Config) (*quic.Conn, error) {
+				switch quicParams.Congestion {
+				case "", "bbr", "reno":
+				default:
+					// brutal is for Hysteria servers, not services, and a panic here, in
+					// a goroutine of http3, would end the process
+					return nil, errors.New("unsupported congestion control over h3: ", quicParams.Congestion)
+				}
+
+				conn, host, err := dial(ctx, "udp", addr)
+				if err != nil {
+					return nil, err
+				}
+				var pktConn net.PacketConn
+				var udpAddr net.Addr
+				switch c := conn.(type) {
+				case *net.PacketConnWrapper:
+					pktConn = c.PacketConn
+					udpAddr = c.RemoteAddr()
+				case *cnc.Connection:
+					pktConn = &internet.FakePacketConn{Conn: c}
+					udpAddr = &net.UDPAddr{IP: []byte{0, 0, 0, 0}}
+				default:
+					conn.Close()
+					return nil, errors.New("failed to dial to dest: unexpected ", reflect.TypeOf(c))
+				}
+
+				// built for each dial with the host as SNI, as for h2: http3 sets the
+				// SNI on a copy, which a pinned CA and the ECH lookup do not see
+				gotlsConfig := tlsConfig.GetTLSConfig(tls.WithDestination(host))
+				// it is for servers, and ChromeParrot refuses a config that has it
+				gotlsConfig.GetCertificate = nil
+				tr := &quic.Transport{Conn: pktConn, DisableGSO: quicParams.DisableGSO}
+				if !quicParams.DisableChromeParrot {
+					tr.ConnectionIDGenerator = quic.ZeroLengthConnectionIDGenerator{}
+				}
+				qconn, err := tr.Dial(ctx, udpAddr, gotlsConfig, cfg)
+				if err != nil {
+					tr.Close()
+					pktConn.Close()
+					return nil, err
+				}
+				stop := context.AfterFunc(connCtx, func() { qconn.CloseWithError(quic.ApplicationErrorCode(http3.ErrCodeNoError), "") })
+				context.AfterFunc(qconn.Context(), func() { stop(); tr.Close(); pktConn.Close() })
+				if quicParams.Congestion != "reno" {
+					congestion.UseBBR(qconn, bbr.Profile(quicParams.BbrProfile))
+				}
+				return qconn, nil
+			},
 		}
 	}
 
@@ -198,18 +318,30 @@ func newServiceClient(streamSettings *internet.MemoryStreamConfig, stall time.Du
 				MaxIdleConnsPerHost: maxConns,
 				MaxConnsPerHost:     maxConns,
 			},
-			secure: &secureTransport{h2: secure(1), h1: secure(maxConns)},
+			secure: https,
 			stall:  stall,
 		},
 	}
 }
 
+// ctxConn is a connection that connCtx no longer closes once it is closed,
+// so that one that ends on its own leaves nothing behind in connCtx
+type ctxConn struct {
+	net.Conn
+	stop func() bool
+}
+
+func (c *ctxConn) Close() error {
+	c.stop()
+	return c.Conn.Close()
+}
+
 // secureTransport keeps a host to one connection, all that h2 needs, as without
 // a limit parallel requests would each dial their own. A host that answers over
 // h1 moves to a transport with more, since h1 carries one request at a time
 type secureTransport struct {
 	h2, h1  http.RoundTripper
-	h1Hosts sync.Map
+	h1Hosts *sync.Map
 }
 
 func (t *secureTransport) RoundTrip(r *http.Request) (*http.Response, error) {
@@ -222,3 +354,129 @@ func (t *secureTransport) RoundTrip(r *http.Request) (*http.Response, error) {
 	}
 	return resp, err
 }
+
+var errSessionClosed = errors.New("the session is closed")
+
+// connPool hands the sessions of a storage the connections of XMUX, each a
+// client of its own made by newClient
+type connPool struct {
+	mu   sync.Mutex
+	xmux *splithttp.XmuxManager
+}
+
+func newConnPool(config *splithttp.XmuxConfig, newClient func(connCtx context.Context) *http.Client) *connPool {
+	var xmuxConfig splithttp.XmuxConfig
+	if config != nil {
+		xmuxConfig = *config
+	}
+	return &connPool{xmux: splithttp.NewXmuxManager(xmuxConfig, func() splithttp.XmuxConn {
+		ctx, cancel := context.WithCancel(context.Background())
+		return &poolConn{next: newClient(ctx).Transport, cancel: cancel}
+	})}
+}
+
+// poolConn is a connection of XMUX, which closes once XMUX drops it and the
+// requests on it end
+type poolConn struct {
+	next   http.RoundTripper
+	cancel context.CancelFunc
+
+	mu       sync.Mutex
+	inflight int
+	closing  bool
+}
+
+func (c *poolConn) IsClosed() bool {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.closing
+}
+
+func (c *poolConn) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.closing = true
+	if c.inflight == 0 {
+		c.cancel()
+	}
+	return nil
+}
+
+func (c *poolConn) done() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.inflight--
+	if c.closing && c.inflight == 0 {
+		c.cancel()
+	}
+}
+
+// roundTrip sends a request counted in inflight by the caller
+func (c *poolConn) roundTrip(r *http.Request) (*http.Response, error) {
+	resp, err := c.next.RoundTrip(r)
+	if err != nil {
+		c.done()
+		return nil, err
+	}
+	resp.Body = &doneBody{ReadCloser: resp.Body, done: sync.OnceFunc(c.done)}
+	return resp, nil
+}
+
+type doneBody struct {
+	io.ReadCloser
+	done func()
+}
+
+func (b *doneBody) Close() error {
+	err := b.ReadCloser.Close()
+	b.done()
+	return err
+}
+
+// sessionTransport sends the requests of one session over a connection of
+// XMUX, and over another once that one has no requests or time left
+type sessionTransport struct {
+	pool *connPool
+
+	mu     sync.Mutex
+	client *splithttp.XmuxClient
+	closed bool
+}
+
+func (t *sessionTransport) RoundTrip(r *http.Request) (*http.Response, error) {
+	t.mu.Lock()
+	if t.closed {
+		t.mu.Unlock()
+		return nil, errSessionClosed
+	}
+	client := t.client
+	if client == nil || client.LeftRequests.Add(-1) < 0 || !client.UnreusableAt.IsZero() && time.Now().After(client.UnreusableAt) {
+		t.pool.mu.Lock()
+		t.client = t.pool.xmux.GetXmuxClient(r.Context())
+		t.pool.mu.Unlock()
+		t.client.AddRunning()
+		t.client.LeftRequests.Add(-1)
+		if client != nil {
+			client.DoneRunning()
+		}
+		client = t.client
+	}
+	// counted under mu, or another request of the session that moves on could
+	// close the connection before this one is sent
+	conn := client.XmuxConn.(*poolConn)
+	conn.mu.Lock()
+	conn.inflight++
+	conn.mu.Unlock()
+	t.mu.Unlock()
+	return conn.roundTrip(r)
+}
+
+func (t *sessionTransport) Close() {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	t.closed = true
+	if t.client != nil {
+		t.client.DoneRunning()
+		t.client = nil
+	}
+}

transport/internet/xdrive/client_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	gotls "crypto/tls"
+	"crypto/x509"
 	"encoding/base64"
 	"errors"
 	"io"
@@ -11,13 +12,22 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"slices"
+	"strings"
 	"sync"
 	"sync/atomic"
 	"testing"
 	"time"
 
+	"github.com/apernet/quic-go"
+	"github.com/apernet/quic-go/http3"
 	xnet "github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/common/net/cnc"
+	"github.com/xtls/xray-core/common/protocol/tls/cert"
+	"github.com/xtls/xray-core/common/utils"
 	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/finalmask"
+	"github.com/xtls/xray-core/transport/internet/finalmask/noise"
+	"github.com/xtls/xray-core/transport/internet/splithttp"
 	"github.com/xtls/xray-core/transport/internet/tls"
 )
 
@@ -75,7 +85,7 @@ func sniForSettings(t *testing.T, serverName string) string {
 	driveFilesURL = "https://www.googleapis.com/drive/v3/files"
 	defer func() { driveFilesURL = prev }()
 
-	client := newServiceClient(settings, 5*time.Second, 8)
+	client := newServiceClient(context.Background(), new(sync.Map), settings, 5*time.Second, 8)
 	req, err := http.NewRequest(http.MethodGet, driveFilesURL, nil)
 	if err != nil {
 		t.Fatalf("request: %v", err)
@@ -145,7 +155,7 @@ func TestServiceClientEndsOnlyStalledRequests(t *testing.T) {
 		}
 	}))
 	defer server.Close()
-	client := newServiceClient(&internet.MemoryStreamConfig{}, stall, 8)
+	client := newServiceClient(context.Background(), new(sync.Map), &internet.MemoryStreamConfig{}, stall, 8)
 
 	fetch := func(path string, body io.Reader) (int, error) {
 		req, err := http.NewRequest(http.MethodPost, server.URL+path, body)
@@ -217,7 +227,7 @@ func TestServiceClientStallOverTLS(t *testing.T) {
 			}
 			time.Sleep(5 * stall)
 		})
-		client := newServiceClient(server.settings(&tls.Config{}), stall, 8)
+		client := newServiceClient(context.Background(), new(sync.Map), server.settings(&tls.Config{}), stall, 8)
 
 		for _, path := range []string{"/stuck", "/silent"} {
 			start := time.Now()
@@ -240,12 +250,13 @@ func TestServiceClientStallOverTLS(t *testing.T) {
 }
 
 // tlsServer is a TLS server that keeps the last hello it got and counts its
-// connections
+// connections, and those closed
 type tlsServer struct {
 	*httptest.Server
-	mu    sync.Mutex
-	hello *gotls.ClientHelloInfo
-	conns atomic.Int32
+	mu     sync.Mutex
+	hello  *gotls.ClientHelloInfo
+	conns  atomic.Int32
+	closed atomic.Int32
 }
 
 func newTLSServer(t *testing.T, config *gotls.Config, handler http.HandlerFunc) *tlsServer {
@@ -260,8 +271,11 @@ func newTLSServer(t *testing.T, config *gotls.Config, handler http.HandlerFunc)
 	}
 	s.TLS = config
 	s.Config.ConnState = func(_ net.Conn, state http.ConnState) {
-		if state == http.StateNew {
+		switch state {
+		case http.StateNew:
 			s.conns.Add(1)
+		case http.StateClosed:
+			s.closed.Add(1)
 		}
 	}
 	s.StartTLS()
@@ -298,7 +312,7 @@ func TestServiceClientSpeaksWhatServerPicks(t *testing.T) {
 	for _, protos := range [][]string{chromeALPN, {"http/1.1"}} {
 		server := newTLSServer(t, &gotls.Config{NextProtos: protos}, func(w http.ResponseWriter, r *http.Request) {})
 		for _, config := range []*tls.Config{{}, {NextProtocol: []string{"h2"}}, {NextProtocol: []string{"http/1.1"}}, {Fingerprint: "unsafe"}} {
-			client := newServiceClient(server.settings(config), 5*time.Second, 8)
+			client := newServiceClient(context.Background(), new(sync.Map), server.settings(config), 5*time.Second, 8)
 			resp, err := client.Get(server.URL)
 			if err != nil {
 				t.Fatalf("server %v, alpn %v, fingerprint %q: %v", protos, config.NextProtocol, config.Fingerprint, err)
@@ -318,7 +332,7 @@ func TestServiceClientSpeaksWhatServerPicks(t *testing.T) {
 // offers certificate compression
 func TestServiceClientDefaultsToChrome(t *testing.T) {
 	server := newTLSServer(t, &gotls.Config{NextProtos: chromeALPN}, func(w http.ResponseWriter, r *http.Request) {})
-	client := newServiceClient(&internet.MemoryStreamConfig{}, 5*time.Second, 8)
+	client := newServiceClient(context.Background(), new(sync.Map), &internet.MemoryStreamConfig{}, 5*time.Second, 8)
 	// the test certificate is not trusted, the hello is all that is needed
 	if resp, err := client.Get(server.URL); err == nil {
 		resp.Body.Close()
@@ -332,6 +346,33 @@ func TestServiceClientDefaultsToChrome(t *testing.T) {
 	}
 }
 
+// a request says it is chrome, as the hello does, unless it says what it is
+func TestServiceClientUserAgent(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		io.WriteString(w, r.UserAgent())
+	}))
+	defer server.Close()
+	client := newServiceClient(context.Background(), new(sync.Map), &internet.MemoryStreamConfig{}, 5*time.Second, 8)
+	for ua, want := range map[string]string{"": utils.ChromeUA, "firefox": utils.FirefoxUA, "custom/1.0": "custom/1.0"} {
+		req, _ := http.NewRequest(http.MethodGet, server.URL, nil)
+		if ua != "" {
+			req.Header.Set("User-Agent", ua)
+		}
+		resp, err := client.Do(req)
+		if err != nil {
+			t.Fatal(err)
+		}
+		got, _ := io.ReadAll(resp.Body)
+		resp.Body.Close()
+		if string(got) != want {
+			t.Errorf("with %q the server got %q, not %q", ua, got, want)
+		}
+		if req.Header.Get("User-Agent") != ua || len(req.Header) > min(len(ua), 1) {
+			t.Errorf("with %q the request was changed to %v", ua, req.Header)
+		}
+	}
+}
+
 // parallel requests share one h2 connection instead of dialing one each, the
 // first ones as the later ones, and next to a host that answers over h1
 func TestServiceClientOneConnection(t *testing.T) {
@@ -339,7 +380,7 @@ func TestServiceClientOneConnection(t *testing.T) {
 		time.Sleep(50 * time.Millisecond)
 	})
 	h1 := newTLSServer(t, &gotls.Config{NextProtos: []string{"http/1.1"}}, func(w http.ResponseWriter, r *http.Request) {})
-	client := newServiceClient(server.settings(&tls.Config{}), 5*time.Second, driveMaxInflight)
+	client := newServiceClient(context.Background(), new(sync.Map), server.settings(&tls.Config{}), 5*time.Second, driveMaxInflight)
 	get := func(url string) {
 		resp, err := client.Get(url)
 		if err != nil {
@@ -395,7 +436,7 @@ func TestServiceClientHTTP1(t *testing.T) {
 		server := newTLSServer(t, &gotls.Config{NextProtos: c.protos, EncryptedClientHelloKeys: echKeys}, func(w http.ResponseWriter, r *http.Request) {
 			time.Sleep(50 * time.Millisecond)
 		})
-		client := newServiceClient(server.settings(c.config), 5*time.Second, 8)
+		client := newServiceClient(context.Background(), new(sync.Map), server.settings(c.config), 5*time.Second, 8)
 		get := func() {
 			resp, err := client.Get(server.URL)
 			if err != nil {
@@ -426,7 +467,7 @@ func TestServiceClientHTTP1(t *testing.T) {
 	// without the keys the server gets the outer hello, which offers the ALPN of
 	// Chrome
 	outer := newTLSServer(t, &gotls.Config{NextProtos: chromeALPN}, func(w http.ResponseWriter, r *http.Request) {})
-	if resp, err := newServiceClient(outer.settings(ech), 5*time.Second, 8).Get(outer.URL); err == nil {
+	if resp, err := newServiceClient(context.Background(), new(sync.Map), outer.settings(ech), 5*time.Second, 8).Get(outer.URL); err == nil {
 		resp.Body.Close()
 	}
 	if hello := outer.lastHello(); hello == nil {
@@ -462,7 +503,7 @@ func TestServiceClientHungHandshake(t *testing.T) {
 		server.Listener = &muteFirst{Listener: server.Listener}
 		server.StartTLS()
 		t.Cleanup(server.Close)
-		client := newServiceClient(server.settings(&tls.Config{Fingerprint: fingerprint}), stall, 8)
+		client := newServiceClient(context.Background(), new(sync.Map), server.settings(&tls.Config{Fingerprint: fingerprint}), stall, 8)
 
 		if _, err := client.Get(server.URL); err == nil {
 			t.Fatalf("fingerprint %q: a request got through a handshake that hung", fingerprint)
@@ -488,7 +529,7 @@ func TestServiceClientClosesFailedHandshake(t *testing.T) {
 
 	for _, fingerprint := range []string{"", "unsafe"} {
 		settings := &internet.MemoryStreamConfig{ProtocolName: protocolName, SecuritySettings: &tls.Config{Fingerprint: fingerprint}}
-		go newServiceClient(settings, 5*time.Second, 8).Get("https://" + ln.Addr().String())
+		go newServiceClient(context.Background(), new(sync.Map), settings, 5*time.Second, 8).Get("https://" + ln.Addr().String())
 		conn, err := ln.Accept()
 		if err != nil {
 			t.Fatal(err)
@@ -503,6 +544,446 @@ func TestServiceClientClosesFailedHandshake(t *testing.T) {
 	}
 }
 
+// afterFuncs counts the functions that context.AfterFunc registers on it and
+// that are not stopped yet
+type afterFuncs struct {
+	context.Context
+	live atomic.Int32
+}
+
+// Value hides the cancelCtx below, which context.AfterFunc would use instead
+func (c *afterFuncs) Value(any) any { return nil }
+
+func (c *afterFuncs) AfterFunc(func()) func() bool {
+	c.live.Add(1)
+	return func() bool {
+		c.live.Add(-1)
+		return true
+	}
+}
+
+// a connection that ends on its own, here after Connection: close, leaves
+// nothing on the context that closes the connections of the client
+func TestServiceClientForgetsClosedConnections(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Connection", "close")
+	}))
+	defer server.Close()
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	connCtx := &afterFuncs{Context: ctx}
+	client := newServiceClient(connCtx, new(sync.Map), &internet.MemoryStreamConfig{}, 5*time.Second, 8)
+
+	for range 4 {
+		resp, err := client.Get(server.URL)
+		if err != nil {
+			t.Fatal(err)
+		}
+		resp.Body.Close()
+	}
+	waitFor(t, "the closed connections to leave the context", func() bool { return connCtx.live.Load() == 0 })
+}
+
 type roundTrip func(*http.Request) (*http.Response, error)
 
 func (f roundTrip) RoundTrip(r *http.Request) (*http.Response, error) { return f(r) }
+
+// "hKeepAlivePeriod" of XMUX sets when an idle h2 connection pings, -1 never,
+// and h3 keeps alive only when it is set
+func TestServiceClientKeepAlive(t *testing.T) {
+	for period, want := range map[int64]time.Duration{0: xnet.ChromeH2KeepAlivePeriod, 20: 20 * time.Second, -1: 0} {
+		settings := &internet.MemoryStreamConfig{ProtocolSettings: &Config{Xmux: &splithttp.XmuxConfig{HKeepAlivePeriod: period}}}
+		client := newServiceClient(context.Background(), new(sync.Map), settings, 5*time.Second, 8)
+		h2 := client.Transport.(*serviceTransport).secure.(*secureTransport).h2.(*http.Transport)
+		if got := h2.HTTP2.SendPingTimeout; got != want {
+			t.Errorf("hKeepAlivePeriod %d pings after %v, want %v", period, got, want)
+		}
+	}
+	for period, want := range map[int64]time.Duration{0: 0, 20: 20 * time.Second, -1: 0} {
+		settings := &internet.MemoryStreamConfig{
+			ProtocolSettings: &Config{Xmux: &splithttp.XmuxConfig{HKeepAlivePeriod: period}},
+			SecuritySettings: &tls.Config{NextProtocol: []string{"h3"}},
+		}
+		client := newServiceClient(context.Background(), new(sync.Map), settings, 5*time.Second, 8)
+		if got := client.Transport.(*serviceTransport).secure.(*http3.Transport).QUICConfig.KeepAlivePeriod; got != want {
+			t.Errorf("hKeepAlivePeriod %d keeps h3 alive every %v, want %v", period, got, want)
+		}
+	}
+}
+
+// h3 is used when "alpn" asks for it alone, and only then
+func TestServiceClientH3Selection(t *testing.T) {
+	for _, c := range []struct {
+		alpn []string
+		h3   bool
+	}{
+		{nil, false},
+		{[]string{"h2"}, false},
+		{[]string{"http/1.1"}, false},
+		{[]string{"h3", "h2"}, false},
+		{[]string{"h2", "h3"}, false},
+		{[]string{"h3"}, true},
+	} {
+		client := newServiceClient(context.Background(), new(sync.Map), &internet.MemoryStreamConfig{SecuritySettings: &tls.Config{NextProtocol: c.alpn}}, 5*time.Second, 8)
+		if _, h3 := client.Transport.(*serviceTransport).secure.(*http3.Transport); h3 != c.h3 {
+			t.Errorf("alpn %v: h3 %v, want %v", c.alpn, h3, c.h3)
+		}
+	}
+	if _, h3 := newServiceClient(context.Background(), new(sync.Map), &internet.MemoryStreamConfig{}, 5*time.Second, 8).Transport.(*serviceTransport).secure.(*http3.Transport); h3 {
+		t.Error("h3 without tlsSettings")
+	}
+}
+
+// h3Server is an http3 server that keeps the SNI of each connection, and counts
+// its connections and those closed
+type h3Server struct {
+	port         xnet.Port
+	hash, caHash [32]byte
+	mu           sync.Mutex
+	snis         []string
+	conns        atomic.Int32
+	closed       atomic.Int32
+}
+
+func newH3Server(t *testing.T, handler http.Handler) *h3Server {
+	t.Helper()
+
+	// ECDSA, as ChromeParrot offers no Ed25519, from a CA of its own
+	ca, caHash := cert.MustGenerate(nil, cert.Authority(true), cert.KeyUsage(x509.KeyUsageCertSign))
+	certificate, hash := cert.MustGenerate(ca, cert.DNSNames("www.googleapis.com", "oauth2.googleapis.com"))
+	key, err := x509.ParsePKCS8PrivateKey(certificate.PrivateKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	conn, err := net.ListenUDP("udp", &net.UDPAddr{IP: net.IPv4(127, 0, 0, 1)})
+	if err != nil {
+		t.Fatal(err)
+	}
+	s := &h3Server{port: xnet.Port(conn.LocalAddr().(*net.UDPAddr).Port), hash: hash, caHash: caHash}
+	server := &http3.Server{
+		Handler: handler,
+		TLSConfig: http3.ConfigureTLSConfig(&gotls.Config{
+			Certificates: []gotls.Certificate{{Certificate: [][]byte{certificate.Certificate, ca.Certificate}, PrivateKey: key}},
+			GetConfigForClient: func(hello *gotls.ClientHelloInfo) (*gotls.Config, error) {
+				s.mu.Lock()
+				s.snis = append(s.snis, hello.ServerName)
+				s.mu.Unlock()
+				return nil, nil
+			},
+		}),
+		ConnContext: func(ctx context.Context, c *quic.Conn) context.Context {
+			s.conns.Add(1)
+			context.AfterFunc(c.Context(), func() { s.closed.Add(1) })
+			return ctx
+		},
+	}
+	go server.Serve(conn)
+	t.Cleanup(func() {
+		server.Close()
+		conn.Close()
+	})
+	return s
+}
+
+// settings sends every host to the server over h3, through a destination built
+// as TCP the way conf builds it, and pins the certificate of the server in config
+func (s *h3Server) settings(config *tls.Config) *internet.MemoryStreamConfig {
+	config.NextProtocol = []string{"h3"}
+	config.PinnedPeerCertSha256 = [][]byte{s.hash[:]}
+	return &internet.MemoryStreamConfig{
+		ProtocolName:     protocolName,
+		Destination:      &xnet.Destination{Address: xnet.LocalHostIP, Port: s.port, Network: xnet.Network_TCP},
+		SecuritySettings: config,
+	}
+}
+
+func (s *h3Server) seenSNIs() []string {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return slices.Sorted(slices.Values(s.snis))
+}
+
+// one client serves two hosts, and each gets its own SNI unless serverName
+// says otherwise, which is also the name a pinned CA checks the certificate for
+func TestServiceClientH3SNI(t *testing.T) {
+	for _, c := range []struct {
+		serverName string
+		pinCA      bool
+		want       []string
+	}{
+		{"", false, []string{"oauth2.googleapis.com", "www.googleapis.com"}},
+		{"www.google.com", false, []string{"www.google.com", "www.google.com"}},
+		{"", true, []string{"oauth2.googleapis.com", "www.googleapis.com"}},
+	} {
+		server := newH3Server(t, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
+		settings := server.settings(&tls.Config{ServerName: c.serverName})
+		if c.pinCA {
+			settings.SecuritySettings.(*tls.Config).PinnedPeerCertSha256 = [][]byte{server.caHash[:]}
+		}
+		client := newServiceClient(context.Background(), new(sync.Map), settings, 5*time.Second, 8)
+		for _, url := range []string{"https://www.googleapis.com/drive/v3/files", "https://oauth2.googleapis.com/token"} {
+			resp, err := client.Get(url)
+			if err != nil {
+				t.Fatalf("serverName %q, pinned CA %v, %s: %v", c.serverName, c.pinCA, url, err)
+			}
+			resp.Body.Close()
+			if resp.Proto != "HTTP/3.0" {
+				t.Errorf("serverName %q, %s: went over %s", c.serverName, url, resp.Proto)
+			}
+		}
+		if snis := server.seenSNIs(); !slices.Equal(snis, c.want) {
+			t.Errorf("serverName %q: SNIs %v, want %v", c.serverName, snis, c.want)
+		}
+	}
+}
+
+// a request that stands still ends over h3 too, and says so
+func TestServiceClientStallOverH3(t *testing.T) {
+	const stall = 200 * time.Millisecond
+	server := newH3Server(t, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/stuck" {
+			w.Write([]byte("x"))
+			w.(http.Flusher).Flush()
+		}
+		time.Sleep(5 * stall)
+	}))
+	client := newServiceClient(context.Background(), new(sync.Map), server.settings(&tls.Config{}), stall, 8)
+
+	for _, path := range []string{"/stuck", "/silent"} {
+		start := time.Now()
+		resp, err := client.Get("https://www.googleapis.com" + path)
+		if err == nil {
+			if resp.Proto != "HTTP/3.0" {
+				t.Fatalf("%s went over %s", path, resp.Proto)
+			}
+			_, err = io.ReadAll(resp.Body)
+			resp.Body.Close()
+		}
+		if !errors.Is(err, errStalled) {
+			t.Errorf("%s gave %v, want %v", path, err, errStalled)
+		}
+		if took := time.Since(start); took > 4*stall {
+			t.Errorf("%s took %v to give up", path, took)
+		}
+	}
+}
+
+// brutal and force-brutal, which are for Hysteria servers, give an error and
+// no panic in a goroutine of http3, where XHTTP and DoH panic on brutal
+func TestServiceClientH3Congestion(t *testing.T) {
+	server := newH3Server(t, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
+	for _, cc := range []string{"", "bbr", "reno", "brutal", "force-brutal"} {
+		settings := server.settings(&tls.Config{})
+		settings.QuicParams = &internet.QuicParams{Congestion: cc, BrutalUp: 1 << 20}
+		resp, err := newServiceClient(context.Background(), new(sync.Map), settings, 5*time.Second, 8).Get("https://www.googleapis.com/")
+		if err == nil {
+			resp.Body.Close()
+		}
+		if brutal := strings.HasSuffix(cc, "brutal"); brutal != (err != nil) || brutal && !strings.Contains(err.Error(), cc) {
+			t.Errorf("congestion %q gave %v", cc, err)
+		}
+	}
+}
+
+// recordConn keeps the datagrams sent through it
+type recordConn struct {
+	net.PacketConn
+	mu     sync.Mutex
+	sent   [][]byte
+	closed atomic.Bool
+}
+
+func (c *recordConn) WriteTo(p []byte, addr net.Addr) (int, error) {
+	c.mu.Lock()
+	c.sent = append(c.sent, bytes.Clone(p))
+	c.mu.Unlock()
+	return c.PacketConn.WriteTo(p, addr)
+}
+
+func (c *recordConn) Close() error {
+	c.closed.Store(true)
+	return c.PacketConn.Close()
+}
+
+// recorder dials UDP through recordConns and keeps them
+type recorder struct {
+	mu    sync.Mutex
+	conns []*recordConn
+}
+
+func (r *recorder) dialUDP(ctx context.Context, dest xnet.Destination) (net.PacketConn, net.Addr, error) {
+	conn, err := internet.DialSystem(ctx, dest, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+	rec := &recordConn{PacketConn: conn.(*xnet.PacketConnWrapper).PacketConn}
+	r.mu.Lock()
+	r.conns = append(r.conns, rec)
+	r.mu.Unlock()
+	return rec, conn.RemoteAddr(), nil
+}
+
+// a connection ends with its socket once it is idle for its idle timeout, as
+// keepalive is off unless asked for, and so does one whose handshake failed,
+// and neither leaves anything on the context that closes the connections
+func TestServiceClientH3Closes(t *testing.T) {
+	server := newH3Server(t, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	for _, pin := range [][]byte{server.hash[:], make([]byte, 32)} {
+		rec := new(recorder)
+		settings := server.settings(&tls.Config{})
+		settings.SecuritySettings.(*tls.Config).PinnedPeerCertSha256 = [][]byte{pin}
+		// ChromeParrot would keep the idle timeout at 30 s
+		settings.QuicParams = &internet.QuicParams{MaxIdleTimeout: 1, DisableChromeParrot: true}
+		settings.FinalMask = finalmask.NewFinalMask(nil, nil, nil, nil, rec.dialUDP, nil)
+		connCtx := &afterFuncs{Context: ctx}
+		resp, err := newServiceClient(connCtx, new(sync.Map), settings, 5*time.Second, 8).Get("https://www.googleapis.com/")
+		if err == nil {
+			resp.Body.Close()
+		}
+		if bytes.Equal(pin, server.hash[:]) != (err == nil) {
+			t.Fatalf("pin %x: %v", pin[:4], err)
+		}
+
+		closed := func() bool {
+			rec.mu.Lock()
+			defer rec.mu.Unlock()
+			return len(rec.conns) == 1 && rec.conns[0].closed.Load()
+		}
+		for deadline := time.Now().Add(5 * time.Second); !closed() && time.Now().Before(deadline); {
+			time.Sleep(10 * time.Millisecond)
+		}
+		if !closed() {
+			t.Errorf("pin %x: the socket was left open", pin[:4])
+		}
+		waitFor(t, "the closed connection to leave the context", func() bool { return connCtx.live.Load() == 0 })
+	}
+}
+
+// cncDialer gives UDP as a stream conn, the way dialerProxy does
+type cncDialer struct{}
+
+func (cncDialer) Dial(ctx context.Context, src xnet.Address, dest xnet.Destination, sockopt *internet.SocketConfig) (net.Conn, error) {
+	conn, err := net.Dial("udp", dest.NetAddr())
+	if err != nil {
+		return nil, err
+	}
+	return cnc.NewConnection(cnc.ConnectionInput(conn), cnc.ConnectionOutput(conn), cnc.ConnectionOnClose(conn)), nil
+}
+
+func (cncDialer) DestIpAddress() net.IP { return nil }
+
+// h3 goes over the stream conn of a dialerProxy too
+func TestServiceClientH3DialerProxy(t *testing.T) {
+	internet.UseAlternativeSystemDialer(cncDialer{})
+	defer internet.UseAlternativeSystemDialer(nil)
+
+	server := newH3Server(t, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
+	resp, err := newServiceClient(context.Background(), new(sync.Map), server.settings(&tls.Config{}), 5*time.Second, 8).Get("https://www.googleapis.com/")
+	if err != nil {
+		t.Fatal(err)
+	}
+	resp.Body.Close()
+	if resp.Proto != "HTTP/3.0" {
+		t.Errorf("went over %s", resp.Proto)
+	}
+}
+
+// xdrive moves data over h3 to a fake Drive, with the noise of a UDP mask sent
+// ahead of the Initial of each connection
+func TestDriveOverH3(t *testing.T) {
+	drive := newFakeDrive(t)
+	server := newH3Server(t, drive.server.Config.Handler)
+	driveTokenURL = "https://oauth2.googleapis.com/token"
+	driveFilesURL = "https://www.googleapis.com/files"
+	driveUploadURL = "https://www.googleapis.com/upload"
+
+	rec := new(recorder)
+	settings := server.settings(&tls.Config{})
+	settings.ProtocolSettings = driveSettings().ProtocolSettings
+	settings.ProtocolSettings.(*Config).Xmux = &splithttp.XmuxConfig{MaxConnections: &splithttp.RangeConfig{From: 4, To: 4}}
+	masks := []finalmask.UDPMask{&noise.Config{Items: []*noise.Item{{Packet: []byte("noise")}}}}
+	settings.FinalMask = finalmask.NewFinalMask(nil, masks, nil, nil, rec.dialUDP, nil)
+
+	client, srv, cleanup := pairWith(t, settings)
+	defer cleanup()
+
+	if _, err := client.Write([]byte("ping")); err != nil {
+		t.Fatalf("client write: %v", err)
+	}
+	expectRead(t, srv, "ping")
+	if _, err := srv.Write([]byte("pong")); err != nil {
+		t.Fatalf("server write: %v", err)
+	}
+	expectRead(t, client, "pong")
+
+	payload := make([]byte, 300000)
+	for i := range payload {
+		payload[i] = byte(i % 251)
+	}
+	go client.Write(payload)
+	if err := srv.SetReadDeadline(time.Now().Add(testPatience)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	got := make([]byte, len(payload))
+	if _, err := io.ReadFull(srv, got); err != nil {
+		t.Fatalf("ReadFull: %v", err)
+	}
+	if !bytes.Equal(got, payload) {
+		t.Fatal("payload mismatch")
+	}
+
+	rec.mu.Lock()
+	defer rec.mu.Unlock()
+	// one for the listener to www.googleapis.com, one for the token to
+	// oauth2.googleapis.com and one of XMUX for each end of the session
+	if len(rec.conns) != 4 {
+		t.Errorf("%d connections went through the mask, want 4", len(rec.conns))
+	}
+	for i, conn := range rec.conns {
+		conn.mu.Lock()
+		sent := conn.sent
+		conn.mu.Unlock()
+		if len(sent) < 2 {
+			t.Errorf("connection %d sent %d datagrams", i, len(sent))
+			continue
+		}
+		// the noise, then a QUIC v1 Initial of 1250 bytes with no source
+		// connection ID, as ChromeParrot sends it
+		first, initial := sent[0], sent[1]
+		if string(first) != "noise" || len(initial) != 1250 || initial[0]&0xf0 != 0xc0 || !bytes.Equal(initial[1:5], []byte{0, 0, 0, 1}) || initial[6+int(initial[5])] != 0 {
+			t.Errorf("connection %d began with %q and %d bytes %x", i, first, len(initial), initial[:min(len(initial), 24)])
+		}
+	}
+}
+
+// over h3 a connection of XMUX is a QUIC connection, which closes once XMUX
+// drops it, so that the server hears of it
+func TestDriveXmuxOverH3(t *testing.T) {
+	drive := newFakeDrive(t)
+	server := newH3Server(t, drive.server.Config.Handler)
+	driveTokenURL = "https://www.googleapis.com/token"
+	driveFilesURL = "https://www.googleapis.com/files"
+	driveUploadURL = "https://www.googleapis.com/upload"
+	settings := server.settings(&tls.Config{})
+	settings.ProtocolSettings = driveSettings().ProtocolSettings
+	settings.ProtocolSettings.(*Config).Xmux = &splithttp.XmuxConfig{HMaxRequestTimes: &splithttp.RangeConfig{From: 3, To: 3}}
+	storage, err := newDriveStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	session := sessionStorage(storage)
+	defer session.Close()
+
+	for _, name := range []string{"a", "b", "c", "d"} {
+		if err := session.Put(context.Background(), "streams/abc/c2s/"+name, []byte("x")); err != nil {
+			t.Fatalf("Put: %v", err)
+		}
+	}
+	// one for the token, the first of XMUX for 3 requests and one more
+	if n := server.conns.Load(); n != 3 {
+		t.Errorf("the token and 4 requests with 3 to a connection took %d connections", n)
+	}
+	waitFor(t, "the first connection of XMUX to close", func() bool { return server.closed.Load() == 1 })
+}

transport/internet/xdrive/config.pb.go

@@ -7,6 +7,7 @@
 package xdrive
 
 import (
+	splithttp "github.com/xtls/xray-core/transport/internet/splithttp"
 	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
 	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
 	reflect "reflect"
@@ -35,6 +36,8 @@ type Config struct {
 	EagerWindowMs     uint32                 `protobuf:"varint,10,opt,name=eager_window_ms,json=eagerWindowMs,proto3" json:"eager_window_ms,omitempty"`
 	HoleTimeoutMs     uint32                 `protobuf:"varint,11,opt,name=hole_timeout_ms,json=holeTimeoutMs,proto3" json:"hole_timeout_ms,omitempty"`
 	Template          string                 `protobuf:"bytes,12,opt,name=template,proto3" json:"template,omitempty"`
+	Xmux              *splithttp.XmuxConfig  `protobuf:"bytes,13,opt,name=xmux,proto3" json:"xmux,omitempty"`
+	S3                *S3Config              `protobuf:"bytes,14,opt,name=s3,proto3" json:"s3,omitempty"`
 	unknownFields     protoimpl.UnknownFields
 	sizeCache         protoimpl.SizeCache
 }
@@ -153,11 +156,93 @@ func (x *Config) GetTemplate() string {
 	return ""
 }
 
+func (x *Config) GetXmux() *splithttp.XmuxConfig {
+	if x != nil {
+		return x.Xmux
+	}
+	return nil
+}
+
+func (x *Config) GetS3() *S3Config {
+	if x != nil {
+		return x.S3
+	}
+	return nil
+}
+
+type S3Config struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	Endpoint      string                 `protobuf:"bytes,1,opt,name=endpoint,proto3" json:"endpoint,omitempty"`
+	Region        string                 `protobuf:"bytes,2,opt,name=region,proto3" json:"region,omitempty"`
+	Bucket        string                 `protobuf:"bytes,3,opt,name=bucket,proto3" json:"bucket,omitempty"`
+	PathStyle     bool                   `protobuf:"varint,4,opt,name=path_style,json=pathStyle,proto3" json:"path_style,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *S3Config) Reset() {
+	*x = S3Config{}
+	mi := &file_transport_internet_xdrive_config_proto_msgTypes[1]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *S3Config) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*S3Config) ProtoMessage() {}
+
+func (x *S3Config) ProtoReflect() protoreflect.Message {
+	mi := &file_transport_internet_xdrive_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 S3Config.ProtoReflect.Descriptor instead.
+func (*S3Config) Descriptor() ([]byte, []int) {
+	return file_transport_internet_xdrive_config_proto_rawDescGZIP(), []int{1}
+}
+
+func (x *S3Config) GetEndpoint() string {
+	if x != nil {
+		return x.Endpoint
+	}
+	return ""
+}
+
+func (x *S3Config) GetRegion() string {
+	if x != nil {
+		return x.Region
+	}
+	return ""
+}
+
+func (x *S3Config) GetBucket() string {
+	if x != nil {
+		return x.Bucket
+	}
+	return ""
+}
+
+func (x *S3Config) GetPathStyle() bool {
+	if x != nil {
+		return x.PathStyle
+	}
+	return false
+}
+
 var File_transport_internet_xdrive_config_proto protoreflect.FileDescriptor
 
 const file_transport_internet_xdrive_config_proto_rawDesc = "" +
 	"\n" +
-	"&transport/internet/xdrive/config.proto\x12\x1exray.transport.internet.xdrive\"\xcb\x03\n" +
+	"&transport/internet/xdrive/config.proto\x12\x1exray.transport.internet.xdrive\x1a)transport/internet/splithttp/config.proto\"\xc8\x04\n" +
 	"\x06Config\x12#\n" +
 	"\rremote_folder\x18\x01 \x01(\tR\fremoteFolder\x12\x18\n" +
 	"\aservice\x18\x02 \x01(\tR\aservice\x12\x18\n" +
@@ -171,7 +256,15 @@ const file_transport_internet_xdrive_config_proto_rawDesc = "" +
 	"\x0feager_window_ms\x18\n" +
 	" \x01(\rR\reagerWindowMs\x12&\n" +
 	"\x0fhole_timeout_ms\x18\v \x01(\rR\rholeTimeoutMs\x12\x1a\n" +
-	"\btemplate\x18\f \x01(\tR\btemplateB5Z3github.com/xtls/xray-core/transport/internet/xdriveb\x06proto3"
+	"\btemplate\x18\f \x01(\tR\btemplate\x12A\n" +
+	"\x04xmux\x18\r \x01(\v2-.xray.transport.internet.splithttp.XmuxConfigR\x04xmux\x128\n" +
+	"\x02s3\x18\x0e \x01(\v2(.xray.transport.internet.xdrive.S3ConfigR\x02s3\"u\n" +
+	"\bS3Config\x12\x1a\n" +
+	"\bendpoint\x18\x01 \x01(\tR\bendpoint\x12\x16\n" +
+	"\x06region\x18\x02 \x01(\tR\x06region\x12\x16\n" +
+	"\x06bucket\x18\x03 \x01(\tR\x06bucket\x12\x1d\n" +
+	"\n" +
+	"path_style\x18\x04 \x01(\bR\tpathStyleB5Z3github.com/xtls/xray-core/transport/internet/xdriveb\x06proto3"
 
 var (
 	file_transport_internet_xdrive_config_proto_rawDescOnce sync.Once
@@ -185,16 +278,20 @@ func file_transport_internet_xdrive_config_proto_rawDescGZIP() []byte {
 	return file_transport_internet_xdrive_config_proto_rawDescData
 }
 
-var file_transport_internet_xdrive_config_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
+var file_transport_internet_xdrive_config_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
 var file_transport_internet_xdrive_config_proto_goTypes = []any{
-	(*Config)(nil), // 0: xray.transport.internet.xdrive.Config
+	(*Config)(nil),               // 0: xray.transport.internet.xdrive.Config
+	(*S3Config)(nil),             // 1: xray.transport.internet.xdrive.S3Config
+	(*splithttp.XmuxConfig)(nil), // 2: xray.transport.internet.splithttp.XmuxConfig
 }
 var file_transport_internet_xdrive_config_proto_depIdxs = []int32{
-	0, // [0:0] is the sub-list for method output_type
-	0, // [0:0] is the sub-list for method input_type
-	0, // [0:0] is the sub-list for extension type_name
-	0, // [0:0] is the sub-list for extension extendee
-	0, // [0:0] is the sub-list for field type_name
+	2, // 0: xray.transport.internet.xdrive.Config.xmux:type_name -> xray.transport.internet.splithttp.XmuxConfig
+	1, // 1: xray.transport.internet.xdrive.Config.s3:type_name -> xray.transport.internet.xdrive.S3Config
+	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_transport_internet_xdrive_config_proto_init() }
@@ -208,7 +305,7 @@ func file_transport_internet_xdrive_config_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: unsafe.Slice(unsafe.StringData(file_transport_internet_xdrive_config_proto_rawDesc), len(file_transport_internet_xdrive_config_proto_rawDesc)),
 			NumEnums:      0,
-			NumMessages:   1,
+			NumMessages:   2,
 			NumExtensions: 0,
 			NumServices:   0,
 		},

transport/internet/xdrive/config.proto

@@ -3,6 +3,8 @@ syntax = "proto3";
 package xray.transport.internet.xdrive;
 option go_package = "github.com/xtls/xray-core/transport/internet/xdrive";
 
+import "transport/internet/splithttp/config.proto";
+
 message Config {
   string remote_folder = 1;
   string service = 2;
@@ -16,4 +18,13 @@ message Config {
   uint32 eager_window_ms = 10;
   uint32 hole_timeout_ms = 11;
   string template = 12;
+  xray.transport.internet.splithttp.XmuxConfig xmux = 13;
+  S3Config s3 = 14;
+}
+
+message S3Config {
+  string endpoint = 1;
+  string region = 2;
+  string bucket = 3;
+  bool path_style = 4;
 }

transport/internet/xdrive/conn.go

@@ -2,6 +2,7 @@ package xdrive
 
 import (
 	"context"
+	"io"
 	"os"
 	"sync"
 	"time"
@@ -11,10 +12,12 @@ import (
 
 var placeholderAddr = &net.TCPAddr{IP: net.IP{127, 0, 0, 1}, Port: 0}
 
+// Conn is a session in segments, walWriter and walReader, or in slots,
+// slotWriter and slotReader
 type Conn struct {
 	cancel  context.CancelFunc
-	writer  *walWriter
-	reader  *walReader
+	writer  io.WriteCloser
+	reader  chunkReader
 	onClose func()
 
 	readBuf []byte
@@ -27,6 +30,13 @@ type Conn struct {
 	closeErr  error
 }
 
+type chunkReader interface {
+	// chunks is closed when there are no more, then Err says why
+	chunks() <-chan []byte
+	Err() error
+	Wake()
+}
+
 func newConn(ctx context.Context, storage Storage, writePrefix, readPrefix string, p params, onClose func()) *Conn {
 	ctx, cancel := context.WithCancel(ctx)
 	return &Conn{
@@ -37,6 +47,16 @@ func newConn(ctx context.Context, storage Storage, writePrefix, readPrefix strin
 	}
 }
 
+func newSlotConn(ctx context.Context, store slotStore, write, read slotTable, p params, onClose func()) *Conn {
+	ctx, cancel := context.WithCancel(ctx)
+	return &Conn{
+		cancel:  cancel,
+		writer:  newSlotWriter(ctx, store, write, p),
+		reader:  newSlotReader(ctx, store, read, p),
+		onClose: onClose,
+	}
+}
+
 func (c *Conn) Read(b []byte) (int, error) {
 	if len(c.readBuf) == 0 {
 		data, err := c.receive()
@@ -53,7 +73,7 @@ func (c *Conn) Read(b []byte) (int, error) {
 func (c *Conn) receive() ([]byte, error) {
 	deadline := c.getDeadline(true)
 	if deadline.IsZero() {
-		data, ok := <-c.reader.ch
+		data, ok := <-c.reader.chunks()
 		if !ok {
 			return nil, c.reader.Err()
 		}
@@ -67,7 +87,7 @@ func (c *Conn) receive() ([]byte, error) {
 	defer timer.Stop()
 
 	select {
-	case data, ok := <-c.reader.ch:
+	case data, ok := <-c.reader.chunks():
 		if !ok {
 			return nil, c.reader.Err()
 		}

transport/internet/xdrive/drive.go

@@ -39,11 +39,21 @@ var (
 )
 
 type driveStorage struct {
+	*driveShared
+	// a session has a client and inflight of its own, see session
+	client   *http.Client
+	inflight chan struct{}
+	release  func()
+}
+
+// driveShared is what the sessions of a storage have in common
+type driveShared struct {
+	conns        *connPool
 	folder       string
 	clientID     string
 	clientSecret string
 	refreshToken string
-	client       *http.Client
+	tokenClient  *http.Client
 	tokenURL     string
 	filesURL     string
 	uploadURL    string
@@ -53,8 +63,6 @@ type driveStorage struct {
 	token       string
 	tokenExpiry time.Time
 
-	inflight chan struct{}
-
 	idMu sync.Mutex
 	ids  map[string]string
 }
@@ -72,21 +80,41 @@ func newDriveStorage(streamSettings *internet.MemoryStreamConfig, config *Config
 		}
 	}
 
+	h1Hosts := new(sync.Map)
+	client := newServiceClient(context.Background(), h1Hosts, streamSettings, driveTimeout, driveMaxInflight)
 	return &driveStorage{
-		folder:       config.RemoteFolder,
-		clientID:     config.Secrets[0],
-		clientSecret: config.Secrets[1],
-		refreshToken: config.Secrets[2],
-		client:       newServiceClient(streamSettings, driveTimeout, driveMaxInflight),
-		tokenURL:     driveTokenURL,
-		filesURL:     driveFilesURL,
-		uploadURL:    driveUploadURL,
-		backoff:      driveInitialBackoff,
-		inflight:     make(chan struct{}, driveMaxInflight),
-		ids:          make(map[string]string),
+		driveShared: &driveShared{
+			conns: newConnPool(config.Xmux, func(connCtx context.Context) *http.Client {
+				return newServiceClient(connCtx, h1Hosts, streamSettings, driveTimeout, driveMaxInflight)
+			}),
+			folder:       config.RemoteFolder,
+			clientID:     config.Secrets[0],
+			clientSecret: config.Secrets[1],
+			refreshToken: config.Secrets[2],
+			tokenClient:  client,
+			tokenURL:     driveTokenURL,
+			filesURL:     driveFilesURL,
+			uploadURL:    driveUploadURL,
+			backoff:      driveInitialBackoff,
+			ids:          make(map[string]string),
+		},
+		client:   client,
+		inflight: make(chan struct{}, driveMaxInflight),
 	}, nil
 }
 
+// session returns a storage for one session, over the connections of XMUX
+// until Close, with the token and ids of s
+func (s *driveStorage) session() Storage {
+	transport := &sessionTransport{pool: s.conns}
+	return &driveStorage{
+		driveShared: s.driveShared,
+		client:      &http.Client{Transport: transport},
+		inflight:    make(chan struct{}, driveMaxInflight),
+		release:     transport.Close,
+	}
+}
+
 func flatten(name string) string {
 	return strings.ReplaceAll(name, "/", flatSeparator)
 }
@@ -115,7 +143,7 @@ func (s *driveStorage) accessToken(ctx context.Context) (string, error) {
 	}
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 
-	resp, err := s.client.Do(req)
+	resp, err := s.tokenClient.Do(req)
 	if err != nil {
 		return "", errors.New("failed to refresh the access token").Base(err)
 	}
@@ -373,24 +401,30 @@ func (s *driveStorage) Put(ctx context.Context, name string, data []byte) error
 }
 
 func (s *driveStorage) putInline(ctx context.Context, name string, data []byte) error {
+	_, err := s.create(ctx, name, base64.StdEncoding.EncodeToString(data))
+	return err
+}
+
+// create makes an object with description and no body and returns its id
+func (s *driveStorage) create(ctx context.Context, name, description string) (string, error) {
 	flat := flatten(name)
 
 	body, err := json.Marshal(map[string]interface{}{
 		"name":        flat,
 		"parents":     []string{s.folder},
-		"description": base64.StdEncoding.EncodeToString(data),
+		"description": description,
 	})
 	if err != nil {
-		return errors.New("failed to build the inline metadata").Base(err)
+		return "", errors.New("failed to build the inline metadata").Base(err)
 	}
 
 	status, payload, err := s.do(ctx, http.MethodPost, s.filesURL+"?fields=id",
 		"application/json; charset=UTF-8", body)
 	if err != nil {
-		return err
+		return "", err
 	}
 	if status != http.StatusOK {
-		return errors.New("Drive rejected the inline upload of ", name,
+		return "", errors.New("Drive rejected the inline upload of ", name,
 			" with ", status, ": ", string(payload))
 	}
 
@@ -398,12 +432,23 @@ func (s *driveStorage) putInline(ctx context.Context, name string, data []byte)
 		ID string `json:"id"`
 	}
 	if err := json.Unmarshal(payload, &parsed); err != nil {
-		return errors.New("failed to parse the Drive upload response").Base(err)
+		return "", errors.New("failed to parse the Drive upload response").Base(err)
 	}
 	if parsed.ID != "" {
 		s.rememberID(flat, parsed.ID)
 	}
-	return nil
+	return parsed.ID, nil
+}
+
+// multipartBody is a body of an upload with metadata and data
+func multipartBody(metadata, data []byte) []byte {
+	var body bytes.Buffer
+	fmt.Fprintf(&body, "--%s\r\nContent-Type: application/json; charset=UTF-8\r\n\r\n", driveBoundary)
+	body.Write(metadata)
+	fmt.Fprintf(&body, "\r\n--%s\r\nContent-Type: application/octet-stream\r\n\r\n", driveBoundary)
+	body.Write(data)
+	fmt.Fprintf(&body, "\r\n--%s--\r\n", driveBoundary)
+	return body.Bytes()
 }
 
 func (s *driveStorage) putMedia(ctx context.Context, name string, data []byte) error {
@@ -417,15 +462,8 @@ func (s *driveStorage) putMedia(ctx context.Context, name string, data []byte) e
 		return errors.New("failed to build the upload metadata").Base(err)
 	}
 
-	var body bytes.Buffer
-	fmt.Fprintf(&body, "--%s\r\nContent-Type: application/json; charset=UTF-8\r\n\r\n", driveBoundary)
-	body.Write(metadata)
-	fmt.Fprintf(&body, "\r\n--%s\r\nContent-Type: application/octet-stream\r\n\r\n", driveBoundary)
-	body.Write(data)
-	fmt.Fprintf(&body, "\r\n--%s--\r\n", driveBoundary)
-
 	status, payload, err := s.do(ctx, http.MethodPost, s.uploadURL,
-		"multipart/related; boundary="+driveBoundary, body.Bytes())
+		"multipart/related; boundary="+driveBoundary, multipartBody(metadata, data))
 	if err != nil {
 		return err
 	}
@@ -452,45 +490,22 @@ func (s *driveStorage) Get(ctx context.Context, name string) ([]byte, error) {
 		return nil, err
 	}
 
-	status, payload, err := s.do(ctx, http.MethodGet,
-		s.filesURL+"/"+url.PathEscape(id)+"?alt=media&supportsAllDrives=true", "", nil)
-	if err != nil {
-		return nil, err
-	}
-	switch status {
-	case http.StatusOK:
-		if len(payload) > 0 {
-			return payload, nil
-		}
-		return s.getInline(ctx, id)
-	case http.StatusNotFound:
+	payload, err := s.readBody(ctx, id)
+	if err == errNotFound {
 		s.forgetID(flat)
-		return nil, errNotFound
-	default:
-		return nil, errors.New("Drive download of ", name, " answered ", status, ": ", string(payload))
 	}
+	if err != nil || len(payload) > 0 {
+		return payload, err
+	}
+	return s.getInline(ctx, id)
 }
 
 func (s *driveStorage) getInline(ctx context.Context, id string) ([]byte, error) {
-	status, payload, err := s.do(ctx, http.MethodGet,
-		s.filesURL+"/"+url.PathEscape(id)+"?fields=description&supportsAllDrives=true", "", nil)
-	if err != nil {
+	description, err := s.readDescription(ctx, id)
+	if err != nil || description == "" {
 		return nil, err
 	}
-	if status != http.StatusOK {
-		return nil, errors.New("Drive answered ", status, " for inline data: ", string(payload))
-	}
-
-	var parsed struct {
-		Description string `json:"description"`
-	}
-	if err := json.Unmarshal(payload, &parsed); err != nil {
-		return nil, errors.New("failed to parse the inline data").Base(err)
-	}
-	if parsed.Description == "" {
-		return nil, nil
-	}
-	data, err := base64.StdEncoding.DecodeString(parsed.Description)
+	data, err := base64.StdEncoding.DecodeString(description)
 	if err != nil {
 		return nil, errors.New("the inline data is not valid base64").Base(err)
 	}
@@ -572,5 +587,81 @@ func (s *driveStorage) List(ctx context.Context, prefix string) ([]Entry, error)
 }
 
 func (s *driveStorage) Close() error {
+	if s.release != nil {
+		s.release()
+	}
 	return nil
 }
+
+// makeSlot implements slotStore
+func (s *driveStorage) makeSlot(ctx context.Context, name string) (string, error) {
+	id, err := s.create(ctx, name, "")
+	if err == nil && id == "" {
+		err = errors.New("Drive returned no id for ", name)
+	}
+	return id, err
+}
+
+// setSlot implements slotStore, a description and a body go in one request
+func (s *driveStorage) setSlot(ctx context.Context, id, description string, body []byte) error {
+	metadata, err := json.Marshal(map[string]string{"description": description})
+	if err != nil {
+		return errors.New("failed to build the slot metadata").Base(err)
+	}
+	target := s.filesURL + "/" + url.PathEscape(id) + "?fields=id&supportsAllDrives=true"
+	contentType := "application/json; charset=UTF-8"
+	if body != nil {
+		upload, _, _ := strings.Cut(s.uploadURL, "?")
+		target = upload + "/" + url.PathEscape(id) + "?uploadType=multipart&fields=id&supportsAllDrives=true"
+		contentType = "multipart/related; boundary=" + driveBoundary
+		metadata = multipartBody(metadata, body)
+	}
+
+	status, payload, err := s.do(ctx, http.MethodPatch, target, contentType, metadata)
+	switch {
+	case err != nil:
+		return err
+	case status == http.StatusNotFound:
+		return errNotFound
+	case status != http.StatusOK:
+		return errors.New("Drive answered ", status, " for the update of ", id, ": ", string(payload))
+	}
+	return nil
+}
+
+// readDescription implements slotStore
+func (s *driveStorage) readDescription(ctx context.Context, id string) (string, error) {
+	status, payload, err := s.do(ctx, http.MethodGet,
+		s.filesURL+"/"+url.PathEscape(id)+"?fields=description&supportsAllDrives=true", "", nil)
+	switch {
+	case err != nil:
+		return "", err
+	case status == http.StatusNotFound:
+		return "", errNotFound
+	case status != http.StatusOK:
+		return "", errors.New("Drive answered ", status, " for the description of ", id, ": ", string(payload))
+	}
+
+	var parsed struct {
+		Description string `json:"description"`
+	}
+	if err := json.Unmarshal(payload, &parsed); err != nil {
+		return "", errors.New("failed to parse the description of ", id).Base(err)
+	}
+	return parsed.Description, nil
+}
+
+// readBody implements slotStore
+func (s *driveStorage) readBody(ctx context.Context, id string) ([]byte, error) {
+	status, payload, err := s.do(ctx, http.MethodGet,
+		s.filesURL+"/"+url.PathEscape(id)+"?alt=media&supportsAllDrives=true", "", nil)
+	switch {
+	case err != nil:
+		return nil, err
+	case status == http.StatusNotFound:
+		return nil, errNotFound
+	case status != http.StatusOK:
+		return nil, errors.New("Drive answered ", status, " for the body of ", id, ": ", string(payload))
+	}
+	return payload, nil
+}

transport/internet/xdrive/drive_live_test.go

@@ -57,7 +57,7 @@ func liveDriveConfig(t *testing.T) *Config {
 		config.Concurrency = uint32(envInt(t, "XRAY_XDRIVE_LIVE_CONCURRENCY"))
 	}
 
-	storage, err := newDriveStorage(nil, config)
+	storage, err := newDriveStorage(&internet.MemoryStreamConfig{}, config)
 	if err != nil {
 		t.Fatalf("newDriveStorage: %v", err)
 	}
@@ -83,7 +83,7 @@ func envInt(t *testing.T, name string) int {
 
 func TestLiveDriveStorage(t *testing.T) {
 	config := liveDriveConfig(t)
-	storage, err := newDriveStorage(nil, config)
+	storage, err := newDriveStorage(&internet.MemoryStreamConfig{}, config)
 	if err != nil {
 		t.Fatalf("newDriveStorage: %v", err)
 	}
@@ -194,7 +194,7 @@ func TestLiveDriveTransport(t *testing.T) {
 
 func TestLiveDriveParallelPut(t *testing.T) {
 	config := liveDriveConfig(t)
-	storage, err := newDriveStorage(nil, config)
+	storage, err := newDriveStorage(&internet.MemoryStreamConfig{}, config)
 	if err != nil {
 		t.Fatalf("newDriveStorage: %v", err)
 	}
@@ -266,7 +266,7 @@ func TestLiveDriveParallelPut(t *testing.T) {
 
 func TestLiveDriveSegmentSweep(t *testing.T) {
 	config := liveDriveConfig(t)
-	storage, err := newDriveStorage(nil, config)
+	storage, err := newDriveStorage(&internet.MemoryStreamConfig{}, config)
 	if err != nil {
 		t.Fatalf("newDriveStorage: %v", err)
 	}
@@ -303,7 +303,7 @@ func TestLiveDriveSegmentSweep(t *testing.T) {
 
 func TestLiveDriveListLag(t *testing.T) {
 	config := liveDriveConfig(t)
-	storage, err := newDriveStorage(nil, config)
+	storage, err := newDriveStorage(&internet.MemoryStreamConfig{}, config)
 	if err != nil {
 		t.Fatalf("newDriveStorage: %v", err)
 	}

transport/internet/xdrive/drive_test.go

@@ -63,6 +63,7 @@ func newFakeDrive(t *testing.T) *fakeDrive {
 	}
 	mux.HandleFunc("/token", record(drive.handleToken))
 	mux.HandleFunc("/upload", record(drive.handleUpload))
+	mux.HandleFunc("/upload/", record(drive.handleUpload))
 	mux.HandleFunc("/files", record(drive.handleFiles))
 	mux.HandleFunc("/files/", record(drive.handleFile))
 	drive.server = httptest.NewServer(mux)
@@ -119,7 +120,8 @@ func (d *fakeDrive) handleUpload(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	var metadata struct {
-		Name string `json:"name"`
+		Name        string `json:"name"`
+		Description string `json:"description"`
 	}
 	if err := json.NewDecoder(metaPart).Decode(&metadata); err != nil {
 		w.WriteHeader(http.StatusBadRequest)
@@ -131,6 +133,22 @@ func (d *fakeDrive) handleUpload(w http.ResponseWriter, r *http.Request) {
 		data, _ = io.ReadAll(dataPart)
 	}
 
+	if id, ok := strings.CutPrefix(r.URL.Path, "/upload/"); ok {
+		// an update of the body and description of a file
+		d.mu.Lock()
+		file := d.files[id]
+		if file != nil {
+			file.data, file.description = data, metadata.Description
+		}
+		d.mu.Unlock()
+		if file == nil || r.Method != http.MethodPatch {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		json.NewEncoder(w).Encode(map[string]string{"id": id})
+		return
+	}
+
 	d.mu.Lock()
 	d.nextID++
 	id := fmt.Sprintf("id-%d", d.nextID)
@@ -223,6 +241,11 @@ func (d *fakeDrive) handleFile(w http.ResponseWriter, r *http.Request) {
 	if ok && r.Method == http.MethodDelete {
 		delete(d.files, id)
 	}
+	var snapshot fakeFile
+	if ok {
+		// a file can be updated, its fields are read here
+		snapshot = *file
+	}
 	d.mu.Unlock()
 
 	if !ok {
@@ -233,11 +256,25 @@ func (d *fakeDrive) handleFile(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusNoContent)
 		return
 	}
-	if strings.Contains(r.URL.RawQuery, "fields=description") {
-		json.NewEncoder(w).Encode(map[string]string{"description": file.description})
+	if r.Method == http.MethodPatch {
+		var meta struct {
+			Description string `json:"description"`
+		}
+		if err := json.NewDecoder(r.Body).Decode(&meta); err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
+		d.mu.Lock()
+		file.description = meta.Description
+		d.mu.Unlock()
+		json.NewEncoder(w).Encode(map[string]string{"id": id})
 		return
 	}
-	w.Write(file.data)
+	if strings.Contains(r.URL.RawQuery, "fields=description") {
+		json.NewEncoder(w).Encode(map[string]string{"description": snapshot.description})
+		return
+	}
+	w.Write(snapshot.data)
 }
 
 func (d *fakeDrive) shouldFail(kind string) bool {
@@ -562,6 +599,12 @@ func TestDriveSharedClient(t *testing.T) {
 	if first != second {
 		t.Fatal("same settings did not share one storage")
 	}
+	// a session has an inflight of its own, as large
+	session := sessionStorage(first).(*driveStorage)
+	defer session.Close()
+	if session.inflight == first.(*driveStorage).inflight || cap(session.inflight) != driveMaxInflight {
+		t.Fatalf("a session shares inflight or has cap %d", cap(session.inflight))
+	}
 }
 
 func TestDriveOldServiceName(t *testing.T) {

transport/internet/xdrive/s3.go

@@ -0,0 +1,518 @@
+package xdrive
+
+import (
+	"bytes"
+	"context"
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/xml"
+	stderrors "errors"
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/transport/internet"
+	"golang.org/x/net/http/httpguts"
+)
+
+type s3Storage struct {
+	*s3Shared
+	client   *http.Client
+	inflight chan struct{}
+	release  func()
+}
+
+type s3Shared struct {
+	conns                *connPool
+	base                 url.URL
+	prefix               string
+	region               string
+	accessKey, secretKey string
+	token                string
+	backoff              time.Duration
+}
+
+func s3Region(region string) string {
+	if region == "" {
+		return "us-east-1"
+	}
+	return region
+}
+
+func ValidateS3Config(c *Config) error {
+	if c == nil || c.S3 == nil {
+		return errors.New(`service "s3" needs an "s3" object`)
+	}
+	u, err := url.Parse(c.S3.Endpoint)
+	if err != nil || (u.Scheme != "https" && u.Scheme != "http") || u.Hostname() == "" ||
+		u.User != nil || u.RawQuery != "" || u.ForceQuery || u.Fragment != "" || u.Opaque != "" {
+		return errors.New("S3 endpoint must be an http(s) URL without credentials, query or fragment")
+	}
+	if !httpguts.ValidHeaderFieldValue(c.S3.Region) || strings.ContainsAny(c.S3.Region, "/, \t") {
+		return errors.New("invalid S3 signing region")
+	}
+	bucket := c.S3.Bucket
+	if !validS3Name(bucket) || strings.Contains(bucket, "/") {
+		return errors.New("S3 needs a bucket name without path separators")
+	}
+	if !c.S3.PathStyle {
+		if net.ParseIP(u.Hostname()) != nil {
+			return errors.New("S3 virtual-hosted addressing requires a DNS endpoint")
+		}
+		// In this mode the bucket is part of the HTTP authority, not its path.
+		if strings.Trim(bucket, "abcdefghijklmnopqrstuvwxyz0123456789-.") != "" || strings.Contains(bucket, "..") ||
+			strings.HasPrefix(bucket, ".") || strings.HasSuffix(bucket, ".") {
+			return errors.New("S3 virtual-hosted addressing requires a DNS-compatible bucket name")
+		}
+	}
+	if !validS3Name(strings.TrimSuffix(c.RemoteFolder, "/")) {
+		return errors.New("S3 remoteFolder must be a nonempty relative prefix without empty, '.' or '..' components")
+	}
+	if len(c.Secrets) < 2 || len(c.Secrets) > 3 || c.Secrets[0] == "" || c.Secrets[1] == "" {
+		return errors.New("S3 needs AccessKeyID, SecretAccessKey and optionally SessionToken in secrets")
+	}
+	for _, secret := range c.Secrets {
+		if !httpguts.ValidHeaderFieldValue(secret) {
+			return errors.New("invalid S3 secret")
+		}
+	}
+	if strings.ContainsAny(c.Secrets[0], "/ ,\t") {
+		return errors.New("invalid S3 AccessKeyID")
+	}
+	return nil
+}
+
+func validS3Name(name string) bool {
+	for _, ch := range name {
+		if ch < 0x20 || ch == 0x7f || ch == '\\' {
+			return false
+		}
+	}
+	for _, part := range strings.Split(name, "/") {
+		if part == "" || part == "." || part == ".." {
+			return false
+		}
+	}
+	return true
+}
+
+func newS3Storage(streamSettings *internet.MemoryStreamConfig, c *Config) (*s3Storage, error) {
+	if err := ValidateS3Config(c); err != nil {
+		return nil, err
+	}
+	base, _ := url.Parse(c.S3.Endpoint)
+	// Encode the endpoint prefix for SigV4 without turning escaped slashes into separators.
+	segments := strings.Split(base.EscapedPath(), "/")
+	for i, segment := range segments {
+		decoded, _ := url.PathUnescape(segment)
+		segments[i] = strings.ReplaceAll(s3EscapePath(decoded), "/", "%2F")
+	}
+	base.RawPath = strings.Join(segments, "/")
+	if !strings.HasSuffix(base.RawPath, "/") {
+		base.Path += "/"
+		base.RawPath += "/"
+	}
+	if c.S3.PathStyle {
+		base.Path += c.S3.Bucket + "/"
+		base.RawPath += s3EscapePath(c.S3.Bucket) + "/"
+	} else {
+		host := c.S3.Bucket + "." + base.Hostname()
+		if base.Port() != "" {
+			host = net.JoinHostPort(host, base.Port())
+		}
+		base.Host = host
+	}
+	if streamSettings == nil {
+		streamSettings = &internet.MemoryStreamConfig{}
+	}
+	h1Hosts := new(sync.Map)
+	newClient := func(ctx context.Context) *http.Client {
+		client := newServiceClient(ctx, h1Hosts, streamSettings, driveTimeout, driveMaxInflight)
+		// A redirect changes the signed host/path. Do not follow it with the old
+		// signature or send the session token to a different endpoint.
+		client.CheckRedirect = s3NoRedirect
+		return client
+	}
+	s := &s3Storage{
+		s3Shared: &s3Shared{
+			conns:     newConnPool(c.Xmux, newClient),
+			base:      *base,
+			prefix:    strings.TrimSuffix(c.RemoteFolder, "/") + "/",
+			region:    s3Region(c.S3.Region),
+			accessKey: c.Secrets[0],
+			secretKey: c.Secrets[1],
+			backoff:   200 * time.Millisecond,
+		},
+		client:   newClient(context.Background()),
+		inflight: make(chan struct{}, driveMaxInflight),
+	}
+	if len(c.Secrets) == 3 {
+		s.token = c.Secrets[2]
+	}
+	return s, nil
+}
+
+func s3NoRedirect(_ *http.Request, _ []*http.Request) error { return http.ErrUseLastResponse }
+
+func (s *s3Storage) session() Storage {
+	transport := &sessionTransport{pool: s.conns}
+	return &s3Storage{
+		s3Shared: s.s3Shared,
+		client:   &http.Client{Transport: transport, CheckRedirect: s3NoRedirect},
+		inflight: make(chan struct{}, cap(s.inflight)),
+		release:  transport.Close,
+	}
+}
+
+func (s *s3Storage) Close() error {
+	if s.release != nil {
+		s.release()
+	}
+	return nil
+}
+
+// SigV4 requires %20 for spaces, uppercase escapes, and unescaped key separators.
+func s3EscapePath(value string) string {
+	const digits = "0123456789ABCDEF"
+	var out strings.Builder
+	for i := 0; i < len(value); i++ {
+		ch := value[i]
+		if ch >= 'a' && ch <= 'z' || ch >= 'A' && ch <= 'Z' || ch >= '0' && ch <= '9' ||
+			ch == '-' || ch == '_' || ch == '.' || ch == '~' || ch == '/' {
+			out.WriteByte(ch)
+		} else {
+			out.WriteByte('%')
+			out.WriteByte(digits[ch>>4])
+			out.WriteByte(digits[ch&15])
+		}
+	}
+	return out.String()
+}
+
+func s3Hash(body []byte) string {
+	sum := sha256.Sum256(body)
+	return hex.EncodeToString(sum[:])
+}
+
+func s3HMAC(key []byte, value string) []byte {
+	h := hmac.New(sha256.New, key)
+	h.Write([]byte(value))
+	return h.Sum(nil)
+}
+
+func (s *s3Storage) sign(req *http.Request, payloadHash string, now time.Time) {
+	stamp, date := now.UTC().Format("20060102T150405Z"), now.UTC().Format("20060102")
+	req.Header.Set("X-Amz-Date", stamp)
+	req.Header.Set("X-Amz-Content-Sha256", payloadHash)
+	headers := "host:" + req.URL.Host + "\nx-amz-content-sha256:" + payloadHash + "\nx-amz-date:" + stamp + "\n"
+	signed := "host;x-amz-content-sha256;x-amz-date"
+	if contentType := req.Header.Get("Content-Type"); contentType != "" {
+		headers = "content-type:" + contentType + "\n" + headers
+		signed = "content-type;" + signed
+	}
+	if s.token != "" {
+		req.Header.Set("X-Amz-Security-Token", s.token)
+		headers += "x-amz-security-token:" + strings.Join(strings.Fields(s.token), " ") + "\n"
+		signed += ";x-amz-security-token"
+	}
+	// Sign the escaped path exactly as sent.
+	canonical := req.Method + "\n" + req.URL.EscapedPath() + "\n" + req.URL.RawQuery + "\n" +
+		headers + "\n" + signed + "\n" + payloadHash
+	scope := date + "/" + s.region + "/s3/aws4_request"
+	toSign := "AWS4-HMAC-SHA256\n" + stamp + "\n" + scope + "\n" + s3Hash([]byte(canonical))
+	key := s3HMAC([]byte("AWS4"+s.secretKey), date)
+	key = s3HMAC(key, s.region)
+	key = s3HMAC(key, "s3")
+	key = s3HMAC(key, "aws4_request")
+	req.Header.Set("Authorization", "AWS4-HMAC-SHA256 Credential="+s.accessKey+"/"+scope+
+		", SignedHeaders="+signed+", Signature="+hex.EncodeToString(s3HMAC(key, toSign)))
+}
+
+func (s *s3Storage) target(key string, query url.Values) string {
+	u := s.base
+	u.Path += key
+	u.RawPath += s3EscapePath(key)
+	// Parameters have fixed ASCII names and one value each; SigV4 uses %20 for spaces.
+	u.RawQuery = strings.ReplaceAll(query.Encode(), "+", "%20")
+	return u.String()
+}
+
+func (s *s3Storage) objectKey(name string) (string, error) {
+	if !validS3Name(name) {
+		return "", errors.New("invalid relative S3 object name")
+	}
+	key := s.prefix + name
+	if len(key) > 1024 {
+		return "", errors.New("S3 object key exceeds 1024 bytes")
+	}
+	return key, nil
+}
+
+// Retries use fresh signatures and hold a concurrency slot until the response body is read.
+func (s *s3Storage) do(ctx context.Context, method, key string, query url.Values, body []byte) (int, []byte, error) {
+	payloadHash := s3Hash(body)
+	backoff := s.backoff
+	var lastErr error
+	var retryAfter time.Duration
+	for attempt := 0; attempt < driveMaxAttempts; attempt++ {
+		if attempt > 0 {
+			delay := max(jitter(backoff), retryAfter)
+			timer := time.NewTimer(min(delay, driveMaxBackoff))
+			select {
+			case <-ctx.Done():
+				timer.Stop()
+				return 0, nil, ctx.Err()
+			case <-timer.C:
+			}
+			backoff = min(backoff*2, driveMaxBackoff)
+		}
+		select {
+		case s.inflight <- struct{}{}:
+		case <-ctx.Done():
+			return 0, nil, ctx.Err()
+		}
+		status, payload, after, err := s.attempt(ctx, method, key, query, body, payloadHash)
+		<-s.inflight
+		if ctx.Err() != nil {
+			return 0, nil, ctx.Err()
+		}
+		if err != nil && (!retryS3Error(err) || status >= 300 && !retryableStatus(status)) {
+			return 0, nil, err
+		}
+		if err == nil && !retryableStatus(status) {
+			return status, payload, nil
+		}
+		lastErr, retryAfter = err, after
+		if lastErr == nil {
+			lastErr = s3ResponseError(method, status, payload)
+		}
+	}
+	return 0, nil, lastErr
+}
+
+func retryS3Error(err error) bool {
+	var dns *net.DNSError
+	if stderrors.As(err, &dns) {
+		return dns.IsTimeout || dns.IsTemporary
+	}
+	var op *net.OpError
+	var network net.Error
+	return stderrors.Is(err, io.EOF) || stderrors.Is(err, io.ErrUnexpectedEOF) || stderrors.Is(err, errStalled) ||
+		stderrors.As(err, &op) || stderrors.As(err, &network) && network.Timeout()
+}
+
+func (s *s3Storage) attempt(ctx context.Context, method, key string, query url.Values, body []byte, hash string) (int, []byte, time.Duration, error) {
+	req, err := http.NewRequestWithContext(ctx, method, s.target(key, query), bytes.NewReader(body))
+	if err != nil {
+		return 0, nil, 0, errors.New("failed to build S3 request")
+	}
+	if method == http.MethodPut {
+		req.Header.Set("Content-Type", "application/octet-stream")
+	}
+	s.sign(req, hash, time.Now())
+	resp, err := s.client.Do(req)
+	if err != nil {
+		if urlErr, ok := err.(*url.Error); ok {
+			err = urlErr.Err
+		}
+		return 0, nil, 0, errors.New("S3 request failed").Base(err)
+	}
+	defer resp.Body.Close()
+	limit := int64(maxSegmentBytes)
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		limit = 64 << 10
+	}
+	payload, err := io.ReadAll(io.LimitReader(resp.Body, limit+1))
+	if err != nil {
+		return resp.StatusCode, nil, 0, errors.New("failed to read S3 response (HTTP ", resp.StatusCode, ")").Base(err)
+	}
+	if int64(len(payload)) > limit {
+		return 0, nil, 0, errors.New("S3 response exceeds size limit")
+	}
+	var after time.Duration
+	if raw := resp.Header.Get("Retry-After"); raw != "" {
+		if seconds, err := strconv.ParseInt(raw, 10, 32); err == nil && seconds > 0 {
+			after = min(time.Duration(seconds)*time.Second, driveMaxBackoff)
+		} else if at, err := http.ParseTime(raw); err == nil {
+			after = min(max(time.Until(at), 0), driveMaxBackoff)
+		}
+	}
+	return resp.StatusCode, payload, after, nil
+}
+
+func s3Missing(status int, payload []byte) bool {
+	if status != http.StatusNotFound {
+		return false
+	}
+	code := s3ErrorCode(payload)
+	return code == "NoSuchKey" || code == "NotFound"
+}
+
+func s3ErrorCode(payload []byte) string {
+	var response struct {
+		XMLName xml.Name `xml:"Error"`
+		Code    string
+	}
+	if xml.Unmarshal(payload, &response) != nil {
+		return ""
+	}
+	return response.Code
+}
+
+func s3ResponseError(method string, status int, payload []byte) error {
+	if code := s3ErrorCode(payload); code != "" {
+		return errors.New("S3 ", method, " answered ", status, " (", strconv.Quote(code), ")")
+	}
+	return errors.New("S3 ", method, " answered ", status)
+}
+
+func (s *s3Storage) Put(ctx context.Context, name string, data []byte) error {
+	key, err := s.objectKey(name)
+	if err != nil {
+		return err
+	}
+	status, payload, err := s.do(ctx, http.MethodPut, key, nil, data)
+	if err != nil {
+		return err
+	}
+	if status != http.StatusOK {
+		return s3ResponseError("PUT", status, payload)
+	}
+	return nil
+}
+
+func (s *s3Storage) Get(ctx context.Context, name string) ([]byte, error) {
+	key, err := s.objectKey(name)
+	if err != nil {
+		return nil, err
+	}
+	status, payload, err := s.do(ctx, http.MethodGet, key, nil, nil)
+	if err != nil {
+		return nil, err
+	}
+	if s3Missing(status, payload) {
+		return nil, errNotFound
+	}
+	if status != http.StatusOK {
+		return nil, s3ResponseError("GET", status, payload)
+	}
+	return payload, nil
+}
+
+type s3ListPage struct {
+	XMLName               xml.Name `xml:"ListBucketResult"`
+	IsTruncated           bool
+	NextContinuationToken string
+	Contents              []struct{ Key string }
+	CommonPrefixes        []struct{ Prefix string }
+}
+
+func (s *s3Storage) list(ctx context.Context, prefix, delimiter string, visit func(*s3ListPage) error) error {
+	query := url.Values{"list-type": {"2"}, "prefix": {prefix}, "max-keys": {"1000"}}
+	if delimiter != "" {
+		query.Set("delimiter", delimiter)
+	}
+	seen := make(map[string]bool)
+	for {
+		status, payload, err := s.do(ctx, http.MethodGet, "", query, nil)
+		if err != nil {
+			return err
+		}
+		if status != http.StatusOK {
+			return s3ResponseError("LIST", status, payload)
+		}
+		var page s3ListPage
+		if err := xml.Unmarshal(payload, &page); err != nil {
+			return errors.New("invalid S3 list response")
+		}
+		// Validate all keys before deleting any objects.
+		for _, item := range page.Contents {
+			if !strings.HasPrefix(item.Key, prefix) {
+				return errors.New("S3 returned an object outside the requested prefix")
+			}
+		}
+		for _, item := range page.CommonPrefixes {
+			if !strings.HasPrefix(item.Prefix, prefix) {
+				return errors.New("S3 returned a directory outside the requested prefix")
+			}
+		}
+		if page.IsTruncated {
+			if page.NextContinuationToken == "" || seen[page.NextContinuationToken] {
+				return errors.New("S3 list pagination did not advance")
+			}
+			seen[page.NextContinuationToken] = true
+		}
+		if err := visit(&page); err != nil {
+			return err
+		}
+		if !page.IsTruncated {
+			return nil
+		}
+		query.Set("continuation-token", page.NextContinuationToken)
+	}
+}
+
+func (s *s3Storage) List(ctx context.Context, prefix string) ([]Entry, error) {
+	key, err := s.objectKey(prefix)
+	if err != nil {
+		return nil, err
+	}
+	key += "/"
+	seen := make(map[string]bool)
+	var entries []Entry
+	add := func(full string) {
+		rest := strings.TrimPrefix(full, key)
+		name, _, _ := strings.Cut(rest, "/")
+		if name != "" && validS3Name(name) && !seen[name] {
+			seen[name] = true
+			entries = append(entries, Entry{Name: name})
+		}
+	}
+	err = s.list(ctx, key, "/", func(page *s3ListPage) error {
+		for _, item := range page.Contents {
+			add(item.Key)
+		}
+		for _, item := range page.CommonPrefixes {
+			add(item.Prefix)
+		}
+		return nil
+	})
+	return entries, err
+}
+
+func (s *s3Storage) deleteObject(ctx context.Context, key string) error {
+	status, payload, err := s.do(ctx, http.MethodDelete, key, nil, nil)
+	if err != nil {
+		return err
+	}
+	if status != http.StatusNoContent && status != http.StatusOK && !s3Missing(status, payload) {
+		return s3ResponseError("DELETE", status, payload)
+	}
+	return nil
+}
+
+// The trailing "/" prevents deleting streams/abcd when removing streams/abc.
+func (s *s3Storage) Delete(ctx context.Context, name string) error {
+	key, err := s.objectKey(name)
+	if err != nil {
+		return err
+	}
+	if err := s.deleteObject(ctx, key); err != nil {
+		return err
+	}
+	return s.list(ctx, key+"/", "", func(page *s3ListPage) error {
+		for _, item := range page.Contents {
+			if err := s.deleteObject(ctx, item.Key); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+}

transport/internet/xdrive/slots.go

@@ -0,0 +1,758 @@
+package xdrive
+
+import (
+	"bytes"
+	"context"
+	"encoding/base64"
+	"encoding/binary"
+	"encoding/json"
+	"hash/crc32"
+	"io"
+	"strconv"
+	"sync"
+	"time"
+
+	"github.com/xtls/xray-core/common/errors"
+)
+
+// A session on a slotStore is carried in a ring of slots for each direction,
+// objects that both peers know by id: segment n is written to slot n % depth
+// and read from it, with nothing to list and no index to wait for. The reader
+// of a direction keeps how far it has read in a watermark, and the writer
+// reuses a slot only once that says what was in it before was taken
+
+const (
+	slotMagic     = "XDRVSL01"
+	slotHeaderLen = len(slotMagic) + 8 + 1 + 4 + 4
+	// slotInlineLimit is how large a segment is at most to go in the description
+	// of its slot, which takes one request less than a body
+	slotInlineLimit = 14 << 10
+	slotDepthLimit  = 8
+	// inlineRampSegments segments of one size in a row double it, from
+	// slotInlineLimit up to segmentBytes
+	inlineRampSegments = 8
+
+	slotInline = 1
+	slotMedia  = 2
+	slotEnd    = 3
+	slotErr    = 4
+)
+
+var (
+	// the head is asked for between slotHuntFloor and slotHuntCeiling, a segment
+	// behind it at about the pace that segments come
+	slotHuntFloor   = 50 * time.Millisecond
+	slotHuntCeiling = 200 * time.Millisecond
+	slotTailMin     = 150 * time.Millisecond
+	slotTailMax     = 800 * time.Millisecond
+	slotFetchAhead  = 6
+
+	slotAckRetry     = 100 * time.Millisecond
+	slotWatermarkTTL = 250 * time.Millisecond
+	slotStallTimeout = 60 * time.Second
+	slotCloseGrace   = 10 * time.Second
+	slotGoneTimeout  = 60 * time.Second
+)
+
+// slotStore is a storage of objects that are written and read again by id,
+// each with a description and a body
+type slotStore interface {
+	makeSlot(ctx context.Context, name string) (string, error)
+	// setSlot sets the description of a slot and, unless body is nil, its body
+	setSlot(ctx context.Context, id, description string, body []byte) error
+	readDescription(ctx context.Context, id string) (string, error)
+	readBody(ctx context.Context, id string) ([]byte, error)
+}
+
+// slotFrame is what the description of a slot says: which segment it holds,
+// and either the segment itself or the size and checksum of the body that does
+type slotFrame struct {
+	seq  int64
+	mode byte
+	size int
+	crc  uint32
+	data []byte
+}
+
+func newSlotFrame(seq int64, mode byte, data []byte) slotFrame {
+	f := slotFrame{seq: seq, mode: mode, size: len(data), crc: crc32.ChecksumIEEE(data)}
+	if mode == slotInline {
+		f.data = data
+	}
+	return f
+}
+
+func (f slotFrame) encode() string {
+	b := make([]byte, slotHeaderLen, slotHeaderLen+len(f.data))
+	copy(b, slotMagic)
+	binary.BigEndian.PutUint64(b[8:], uint64(f.seq))
+	b[16] = f.mode
+	binary.BigEndian.PutUint32(b[17:], uint32(f.size))
+	binary.BigEndian.PutUint32(b[21:], f.crc)
+	return base64.StdEncoding.EncodeToString(append(b, f.data...))
+}
+
+func decodeSlot(description string) (slotFrame, bool) {
+	b, err := base64.StdEncoding.DecodeString(description)
+	if err != nil || len(b) < slotHeaderLen || string(b[:len(slotMagic)]) != slotMagic {
+		return slotFrame{}, false
+	}
+	f := slotFrame{
+		seq:  int64(binary.BigEndian.Uint64(b[8:])),
+		mode: b[16],
+		size: int(binary.BigEndian.Uint32(b[17:])),
+		crc:  binary.BigEndian.Uint32(b[21:]),
+	}
+	if f.mode == slotInline {
+		f.data = b[slotHeaderLen:]
+		if !f.holds(f.data) {
+			return slotFrame{}, false
+		}
+	}
+	return f, true
+}
+
+// holds reports whether body is the one that f is about, which a body read
+// right after its description need not be yet
+func (f slotFrame) holds(body []byte) bool {
+	return len(body) == f.size && crc32.ChecksumIEEE(body) == f.crc
+}
+
+// slotTable is the ring of one direction: the ids of its slots and of the
+// watermark of its reader
+type slotTable struct {
+	Slots     []string `json:"s"`
+	Watermark string   `json:"w"`
+}
+
+// ring is what a client announces a session with, the tables are named from
+// its side
+type ring struct {
+	Up   slotTable `json:"u"`
+	Down slotTable `json:"d"`
+}
+
+func decodeRing(b []byte) (ring, bool) {
+	var r ring
+	if json.Unmarshal(b, &r) != nil || len(r.Up.Slots) == 0 || len(r.Down.Slots) == 0 ||
+		r.Up.Watermark == "" || r.Down.Watermark == "" {
+		return ring{}, false
+	}
+	return r, true
+}
+
+// makeRing makes the slots and watermarks of a session, all at once
+func makeRing(ctx context.Context, store slotStore, session string, p params) (ring, error) {
+	depth := min(max(p.concurrency, 2), slotDepthLimit)
+	r := ring{
+		Up:   slotTable{Slots: make([]string, depth)},
+		Down: slotTable{Slots: make([]string, depth)},
+	}
+	var (
+		wg      sync.WaitGroup
+		errOnce sync.Once
+		err     error
+	)
+	create := func(id *string, name string) {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			var e error
+			if *id, e = store.makeSlot(ctx, name); e != nil {
+				errOnce.Do(func() { err = e })
+			}
+		}()
+	}
+	for _, t := range []struct {
+		table  *slotTable
+		prefix string
+	}{{&r.Up, uplinkPrefix(session)}, {&r.Down, downlinkPrefix(session)}} {
+		for i := range t.table.Slots {
+			create(&t.table.Slots[i], t.prefix+"/s"+strconv.Itoa(i))
+		}
+		create(&t.table.Watermark, t.prefix+"/w")
+	}
+	wg.Wait()
+	return r, err
+}
+
+func readWatermark(ctx context.Context, store slotStore, id string) (int64, error) {
+	d, err := store.readDescription(ctx, id)
+	if err != nil || d == "" {
+		return -1, err
+	}
+	return strconv.ParseInt(d, 10, 64)
+}
+
+type slotWriter struct {
+	ctx   context.Context
+	store slotStore
+	table slotTable
+	params
+	// slots has a token for each segment on its way, at most one for each slot
+	slots chan struct{}
+	wg    sync.WaitGroup
+
+	mu       sync.Mutex
+	buf      []byte
+	seq      int64
+	size     int
+	full     int
+	lastSize int
+	held     int
+	closed   bool
+	err      error
+
+	// ackMu is held while the watermark is read, which other uploads wait for
+	ackMu    sync.Mutex
+	acked    int64
+	ackedAt  time.Time
+	progress time.Time
+}
+
+func newSlotWriter(ctx context.Context, store slotStore, table slotTable, p params) *slotWriter {
+	w := &slotWriter{
+		ctx:      ctx,
+		store:    store,
+		table:    table,
+		params:   p,
+		slots:    make(chan struct{}, len(table.Slots)),
+		size:     min(slotInlineLimit, p.segmentBytes),
+		acked:    -1,
+		progress: time.Now(),
+	}
+	go w.flushLoop()
+	return w
+}
+
+func (w *slotWriter) Write(p []byte) (int, error) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	if w.err != nil {
+		return 0, w.err
+	}
+	if w.closed {
+		return 0, io.ErrClosedPipe
+	}
+
+	w.buf = append(w.buf, p...)
+	for len(w.buf) >= w.size {
+		if err := w.flushLocked(); err != nil {
+			return 0, err
+		}
+	}
+	return len(p), nil
+}
+
+func (w *slotWriter) flushLoop() {
+	ticker := time.NewTicker(w.flushInterval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-w.ctx.Done():
+			return
+		case <-ticker.C:
+			w.mu.Lock()
+			if !w.closed && w.err == nil && len(w.buf) > 0 && w.readyToFlush() {
+				w.flushLocked()
+			}
+			done := w.closed || w.err != nil
+			w.mu.Unlock()
+			if done {
+				return
+			}
+		}
+	}
+}
+
+func (w *slotWriter) readyToFlush() bool {
+	grew := len(w.buf) > w.lastSize
+	w.lastSize = len(w.buf)
+
+	if grew && w.held < maxCoalescedTicks {
+		w.held++
+		return false
+	}
+	w.held = 0
+	return true
+}
+
+// flushLocked sends a segment off buf once a slot is free, which it waits for
+// without w.mu, so that a reader that falls behind holds Write back. w.mu is
+// held
+func (w *slotWriter) flushLocked() error {
+	w.mu.Unlock()
+	select {
+	case w.slots <- struct{}{}:
+	case <-w.ctx.Done():
+		w.mu.Lock()
+		return w.ctx.Err()
+	}
+	w.mu.Lock()
+	if w.err != nil || len(w.buf) == 0 {
+		<-w.slots
+		return w.err
+	}
+
+	n := min(len(w.buf), w.size)
+	if len(w.buf) > 4*slotInlineLimit {
+		// a burst goes at the full size at once
+		n = min(len(w.buf), w.segmentBytes)
+	}
+	if n == w.size && w.size < w.segmentBytes {
+		if w.full++; w.full == inlineRampSegments {
+			w.full = 0
+			w.size = min(2*w.size, w.segmentBytes)
+		}
+	}
+
+	chunk := bytes.Clone(w.buf[:n])
+	w.buf = append(w.buf[:0], w.buf[n:]...)
+	seq := w.seq
+	w.seq++
+	w.lastSize = len(w.buf)
+	w.held = 0
+
+	w.wg.Add(1)
+	go w.upload(seq, chunk)
+	return nil
+}
+
+func (w *slotWriter) slotID(seq int64) string {
+	return w.table.Slots[seq%int64(len(w.table.Slots))]
+}
+
+func (w *slotWriter) upload(seq int64, chunk []byte) {
+	defer w.wg.Done()
+	defer func() { <-w.slots }()
+
+	mode := byte(slotMedia)
+	if len(chunk) <= slotInlineLimit {
+		mode = slotInline
+	}
+	if err := w.await(seq); err != nil {
+		w.fail(errors.New("failed to store segment ", seq).Base(err))
+		return
+	}
+	if err := w.write(seq, mode, chunk); err != nil {
+		w.fail(errors.New("failed to store segment ", seq).Base(err))
+		// the slot is free, the reader learns there what happened
+		w.write(seq, slotErr, nil)
+	}
+}
+
+func (w *slotWriter) write(seq int64, mode byte, data []byte) error {
+	f := newSlotFrame(seq, mode, data)
+	var body []byte
+	if mode == slotMedia {
+		body = data
+	}
+	return w.store.setSlot(w.ctx, w.slotID(seq), f.encode(), body)
+}
+
+// drained reports whether the reader took what the slot of seq held a lap
+// before. The watermark is read again only after slotWatermarkTTL, as one
+// that is old costs a wait but never what is in a slot
+func (w *slotWriter) drained(seq int64) (bool, error) {
+	w.ackMu.Lock()
+	defer w.ackMu.Unlock()
+
+	before := seq - int64(len(w.table.Slots))
+	if w.acked >= before {
+		return true, nil
+	}
+	if time.Since(w.ackedAt) < slotWatermarkTTL {
+		return false, nil
+	}
+	acked, err := readWatermark(w.ctx, w.store, w.table.Watermark)
+	if err != nil {
+		return false, err
+	}
+	w.ackedAt = time.Now()
+	if acked > w.acked {
+		w.acked, w.progress = acked, w.ackedAt
+	}
+	return w.acked >= before, nil
+}
+
+// await waits for drained, for slotStallTimeout at most, or slotCloseGrace
+// without progress once the writer is closed
+func (w *slotWriter) await(seq int64) error {
+	start := time.Now()
+	wait := slotAckRetry
+	for {
+		ok, err := w.drained(seq)
+		if ok {
+			return nil
+		}
+		w.mu.Lock()
+		closed := w.closed
+		w.mu.Unlock()
+		w.ackMu.Lock()
+		still := time.Since(w.progress)
+		w.ackMu.Unlock()
+		if time.Since(start) > slotStallTimeout || closed && still > slotCloseGrace {
+			return errors.New("the reader took nothing from slot ", w.slotID(seq), " for ", still).Base(err)
+		}
+
+		if err != nil {
+			wait = min(2*wait, 2*time.Second)
+		} else {
+			wait = slotAckRetry
+		}
+		select {
+		case <-w.ctx.Done():
+			return w.ctx.Err()
+		case <-time.After(wait):
+		}
+	}
+}
+
+func (w *slotWriter) fail(err error) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	if w.err == nil {
+		w.err = err
+	}
+}
+
+func (w *slotWriter) Close() error {
+	w.mu.Lock()
+	if w.closed {
+		w.mu.Unlock()
+		return nil
+	}
+	w.closed = true
+	for len(w.buf) > 0 && w.err == nil {
+		if err := w.flushLocked(); err != nil {
+			w.mu.Unlock()
+			return err
+		}
+	}
+	seq := w.seq
+	w.mu.Unlock()
+
+	w.ackMu.Lock()
+	w.progress = time.Now()
+	w.ackMu.Unlock()
+
+	w.wg.Wait()
+
+	w.mu.Lock()
+	err := w.err
+	w.mu.Unlock()
+	if err != nil {
+		return err
+	}
+	if err := w.await(seq); err != nil {
+		return err
+	}
+	return w.write(seq, slotEnd, nil)
+}
+
+type slotReader struct {
+	ctx   context.Context
+	store slotStore
+	table slotTable
+	params
+
+	ch   chan []byte
+	wake chan struct{}
+	acks chan struct{}
+
+	mu      sync.Mutex
+	head    int64
+	started bool
+	// hitAt is when a segment last came and gap the time between them, activeAt
+	// when a segment came, was seen coming or Wake. Nothing for the eager window
+	// is idle, and active is closed when that ends
+	hitAt    time.Time
+	gap      time.Duration
+	activeAt time.Time
+	active   chan struct{}
+	err      error
+}
+
+func newSlotReader(ctx context.Context, store slotStore, table slotTable, p params) *slotReader {
+	r := &slotReader{
+		ctx:      ctx,
+		store:    store,
+		table:    table,
+		params:   p,
+		ch:       make(chan []byte, p.concurrency),
+		wake:     make(chan struct{}, 1),
+		acks:     make(chan struct{}, 1),
+		hitAt:    time.Now(),
+		activeAt: time.Now(),
+		active:   make(chan struct{}),
+	}
+	go r.run()
+	go r.ackLoop()
+	return r
+}
+
+func (r *slotReader) chunks() <-chan []byte {
+	return r.ch
+}
+
+// Wake has the head asked for now, as an answer is likely to come
+func (r *slotReader) Wake() {
+	r.mu.Lock()
+	r.touch()
+	r.mu.Unlock()
+	select {
+	case r.wake <- struct{}{}:
+	default:
+	}
+}
+
+func (r *slotReader) slotID(seq int64) string {
+	return r.table.Slots[seq%int64(len(r.table.Slots))]
+}
+
+type slotFetch struct {
+	ready chan struct{}
+	// promoted is closed when the segment becomes the head
+	promoted chan struct{}
+	body     []byte
+	end      bool
+	err      error
+}
+
+func (r *slotReader) run() {
+	defer close(r.ch)
+	ctx, cancel := context.WithCancel(r.ctx)
+	defer cancel()
+
+	fetches := make(map[int64]*slotFetch)
+	for {
+		r.mu.Lock()
+		head, started := r.head, r.started
+		r.mu.Unlock()
+
+		window := 1
+		if started {
+			window = min(slotFetchAhead, len(r.table.Slots))
+		}
+		for i := range window {
+			seq := head + int64(i)
+			if fetches[seq] == nil {
+				fetches[seq] = &slotFetch{ready: make(chan struct{}), promoted: make(chan struct{})}
+				go r.fetch(ctx, seq, i, fetches[seq])
+			}
+		}
+
+		f := fetches[head]
+		select {
+		case <-f.ready:
+		case <-ctx.Done():
+			return
+		}
+		delete(fetches, head)
+		if f.err != nil {
+			r.setErr(f.err)
+			return
+		}
+		if f.end {
+			return
+		}
+
+		// the slot is free once the bytes are here, not once they are read
+		r.mu.Lock()
+		r.head++
+		r.started = true
+		r.mu.Unlock()
+		if next := fetches[head+1]; next != nil {
+			close(next.promoted)
+		}
+		select {
+		case r.acks <- struct{}{}:
+		default:
+		}
+
+		select {
+		case r.ch <- f.body:
+		case <-ctx.Done():
+			return
+		}
+	}
+}
+
+func (r *slotReader) isHead(seq int64) bool {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	return r.head == seq
+}
+
+// fetch asks for the slot of seq until it holds seq: the head often, a segment
+// behind it at the pace that segments come, as it would wait for the head anyway
+func (r *slotReader) fetch(ctx context.Context, seq int64, offset int, f *slotFetch) {
+	defer close(f.ready)
+	if offset > 0 && !r.hold(ctx, time.Duration(offset)*r.pace(), f.promoted, nil) {
+		return
+	}
+
+	id := r.slotID(seq)
+	backoff := slotHuntFloor
+	var goneSince, warnedAt time.Time
+	for {
+		description, err := r.store.readDescription(ctx, id)
+		frame, ok := decodeSlot(description)
+		switch {
+		case err == nil && ok && frame.seq == seq:
+			// what follows it is asked for while its body comes
+			r.mu.Lock()
+			r.touch()
+			r.mu.Unlock()
+			switch frame.mode {
+			case slotEnd:
+				f.end = true
+				return
+			case slotErr:
+				f.err = errors.New("the peer could not store segment ", seq)
+				return
+			case slotInline:
+				f.body = frame.data
+				r.hit()
+				return
+			case slotMedia:
+				if body, err := r.store.readBody(ctx, id); err == nil && frame.holds(body) {
+					f.body = body
+					r.hit()
+					return
+				}
+			}
+		case err == errNotFound:
+			if goneSince.IsZero() {
+				goneSince = time.Now()
+			} else if time.Since(goneSince) > slotGoneTimeout && r.isHead(seq) {
+				f.err = errors.New("slot ", id, " of segment ", seq, " is gone").Base(err)
+				return
+			}
+		case err != nil:
+			goneSince = time.Time{}
+			if ctx.Err() == nil && time.Since(warnedAt) > 10*time.Second {
+				warnedAt = time.Now()
+				errors.LogWarningInner(ctx, err, "failed to read slot ", id)
+			}
+		}
+
+		r.mu.Lock()
+		head, idle, active := r.head == seq, time.Since(r.activeAt) > r.eagerWindow, r.active
+		r.mu.Unlock()
+		wait, a, b := backoff, (<-chan struct{})(r.wake), (<-chan struct{})(nil)
+		switch {
+		case head:
+			ceiling := slotHuntCeiling
+			if idle {
+				ceiling = max(ceiling, r.maxPollInterval)
+			}
+			backoff = min(2*backoff, ceiling)
+		case idle:
+			// only the head is asked for until something comes
+			wait, a, b, backoff = 0, f.promoted, active, slotHuntFloor
+		default:
+			wait, a, backoff = min(max(r.pace(), slotTailMin), slotTailMax), f.promoted, slotHuntFloor
+		}
+		if !r.hold(ctx, wait, a, b) {
+			return
+		}
+	}
+}
+
+// pace is about how long segments take to come one after the other
+func (r *slotReader) pace() time.Duration {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	return min(max(r.gap, 300*time.Millisecond), 3*time.Second)
+}
+
+func (r *slotReader) hit() {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if gap := time.Since(r.hitAt); r.gap == 0 {
+		r.gap = gap
+	} else {
+		r.gap = (r.gap + gap) / 2
+	}
+	r.hitAt = time.Now()
+	r.touch()
+}
+
+// touch notes that something came or is likely to. r.mu is held
+func (r *slotReader) touch() {
+	if time.Since(r.activeAt) > r.eagerWindow {
+		close(r.active)
+		r.active = make(chan struct{})
+	}
+	r.activeAt = time.Now()
+}
+
+// hold waits d, unless d is 0, or until a or b is closed or has a value
+func (r *slotReader) hold(ctx context.Context, d time.Duration, a, b <-chan struct{}) bool {
+	var timeout <-chan time.Time
+	if d > 0 {
+		timer := time.NewTimer(d)
+		defer timer.Stop()
+		timeout = timer.C
+	}
+	select {
+	case <-ctx.Done():
+		return false
+	case <-a:
+	case <-b:
+	case <-timeout:
+	}
+	return true
+}
+
+// ackLoop writes the watermark when the head moves, the last head only if it
+// moved more than once meanwhile
+func (r *slotReader) ackLoop() {
+	acked := int64(-1)
+	wait := slotAckRetry
+	for {
+		select {
+		case <-r.ctx.Done():
+			return
+		case <-r.acks:
+		}
+		for {
+			r.mu.Lock()
+			want := r.head - 1
+			r.mu.Unlock()
+			if want <= acked {
+				break
+			}
+			if err := r.store.setSlot(r.ctx, r.table.Watermark, strconv.FormatInt(want, 10), nil); err == nil {
+				acked, wait = want, slotAckRetry
+				continue
+			}
+			wait = min(2*wait, 5*time.Second)
+			select {
+			case <-r.ctx.Done():
+				return
+			case <-time.After(wait):
+			}
+		}
+	}
+}
+
+func (r *slotReader) setErr(err error) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.err == nil {
+		r.err = err
+	}
+}
+
+func (r *slotReader) Err() error {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.err != nil {
+		return r.err
+	}
+	return io.EOF
+}

transport/internet/xdrive/slots_test.go

@@ -0,0 +1,309 @@
+package xdrive
+
+import (
+	"bytes"
+	"context"
+	"encoding/base64"
+	"errors"
+	"io"
+	"math/rand"
+	"os"
+	"strconv"
+	"sync"
+	"testing"
+	"time"
+)
+
+type memSlots struct {
+	mu     sync.Mutex
+	next   int
+	descs  map[string]string
+	bodies map[string][]byte
+	reads  int
+}
+
+func newMemSlots() *memSlots {
+	return &memSlots{descs: make(map[string]string), bodies: make(map[string][]byte)}
+}
+
+func (m *memSlots) makeSlot(ctx context.Context, name string) (string, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.next++
+	id := "slot-" + strconv.Itoa(m.next)
+	m.descs[id] = ""
+	return id, nil
+}
+
+func (m *memSlots) setSlot(ctx context.Context, id, description string, body []byte) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if _, ok := m.descs[id]; !ok {
+		return errNotFound
+	}
+	m.descs[id] = description
+	if body != nil {
+		m.bodies[id] = bytes.Clone(body)
+	}
+	return nil
+}
+
+func (m *memSlots) readDescription(ctx context.Context, id string) (string, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.reads++
+	d, ok := m.descs[id]
+	if !ok {
+		return "", errNotFound
+	}
+	return d, nil
+}
+
+func (m *memSlots) readBody(ctx context.Context, id string) ([]byte, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	return m.bodies[id], nil
+}
+
+// the slots of all tests are asked for often, set once as a goroutine of a
+// closed Conn may still read them
+func init() {
+	slotHuntFloor, slotHuntCeiling, slotTailMin, slotTailMax = 2*time.Millisecond, 10*time.Millisecond, 5*time.Millisecond, 20*time.Millisecond
+	slotAckRetry, slotWatermarkTTL = 2*time.Millisecond, 2*time.Millisecond
+}
+
+func slotPair(t *testing.T, store slotStore, concurrency, segmentBytes uint32) (*Conn, *Conn) {
+	t.Helper()
+	p := paramsFromConfig(&Config{
+		SegmentBytes:      segmentBytes,
+		FlushIntervalMs:   1,
+		PollIntervalMs:    1,
+		MaxPollIntervalMs: 20,
+		EagerWindowMs:     50,
+		Concurrency:       concurrency,
+	})
+	r, err := makeRing(context.Background(), store, "session", p)
+	if err != nil {
+		t.Fatal(err)
+	}
+	client := newSlotConn(context.Background(), store, r.Up, r.Down, p, nil)
+	server := newSlotConn(context.Background(), store, r.Down, r.Up, p, nil)
+	t.Cleanup(func() {
+		client.Close()
+		server.Close()
+	})
+	for _, c := range []*Conn{client, server} {
+		c.SetReadDeadline(time.Now().Add(30 * time.Second))
+	}
+	return client, server
+}
+
+// writeAll writes payload in pieces of random size, and closes c if end, the
+// error goes to errs
+func writeAll(c *Conn, payload []byte, end bool, errs chan<- error) {
+	go func() {
+		rng := rand.New(rand.NewSource(1))
+		for len(payload) > 0 {
+			n := min(len(payload), 1+rng.Intn(40<<10))
+			if _, err := c.Write(payload[:n]); err != nil {
+				errs <- err
+				return
+			}
+			payload = payload[n:]
+		}
+		var err error
+		if end {
+			err = c.Close()
+		}
+		errs <- err
+	}()
+}
+
+func readAll(t *testing.T, c *Conn, want []byte) {
+	t.Helper()
+	got, err := io.ReadAll(c)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(got, want) {
+		t.Fatalf("got %d bytes, not the %d that were sent", len(got), len(want))
+	}
+}
+
+func randomPayload(n int) []byte {
+	payload := make([]byte, n)
+	rand.New(rand.NewSource(int64(n))).Read(payload)
+	return payload
+}
+
+func TestSlotFrame(t *testing.T) {
+	data := []byte("hello")
+	f, ok := decodeSlot(newSlotFrame(7, slotInline, data).encode())
+	if !ok || f.seq != 7 || f.mode != slotInline || !bytes.Equal(f.data, data) {
+		t.Fatalf("inline frame came back as %+v %v", f, ok)
+	}
+
+	body := randomPayload(100)
+	f, ok = decodeSlot(newSlotFrame(8, slotMedia, body).encode())
+	if !ok || f.seq != 8 || f.mode != slotMedia || f.data != nil || !f.holds(body) || f.holds(body[1:]) {
+		t.Fatalf("media frame came back as %+v %v", f, ok)
+	}
+
+	corrupt, _ := base64.StdEncoding.DecodeString(newSlotFrame(1, slotInline, data).encode())
+	corrupt[len(corrupt)-1]++
+	for _, broken := range []string{
+		"", "not base64", newSlotFrame(1, slotInline, data).encode()[:20], "WERSVlNMMDE=",
+		base64.StdEncoding.EncodeToString(corrupt),
+	} {
+		if _, ok := decodeSlot(broken); ok {
+			t.Errorf("%q decoded", broken)
+		}
+	}
+}
+
+// both sides send more segments than the ring has slots at once, small ones
+// that go in descriptions and large ones that go in bodies, then one closes
+// and the other reads EOF
+func TestSlotConnRoundTrip(t *testing.T) {
+	client, server := slotPair(t, newMemSlots(), 4, 64<<10)
+	up, down := randomPayload(1<<20), randomPayload(300<<10)
+	errs := make(chan error, 2)
+	writeAll(client, up, false, errs)
+	writeAll(server, down, false, errs)
+
+	for _, c := range []struct {
+		conn *Conn
+		want []byte
+	}{{server, up}, {client, down}} {
+		got := make([]byte, len(c.want))
+		if _, err := io.ReadFull(c.conn, got); err != nil {
+			t.Fatal(err)
+		}
+		if !bytes.Equal(got, c.want) {
+			t.Fatal("what came is not what was sent")
+		}
+	}
+	for range 2 {
+		if err := <-errs; err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	if err := client.Close(); err != nil {
+		t.Fatal(err)
+	}
+	readAll(t, server, nil)
+}
+
+// a reader that does not read holds the writer back instead of losing what a
+// lap of the ring would overwrite
+func TestSlotConnSlowReader(t *testing.T) {
+	client, server := slotPair(t, newMemSlots(), 2, 16<<10)
+	payload := randomPayload(400 << 10)
+	errs := make(chan error, 1)
+	writeAll(client, payload, true, errs)
+
+	time.Sleep(200 * time.Millisecond)
+	readAll(t, server, payload)
+	if err := <-errs; err != nil {
+		t.Fatal(err)
+	}
+}
+
+// the next segment is asked for at once when it becomes the head, not after
+// the wait it had as one that was fetched ahead
+func TestSlotLatency(t *testing.T) {
+	client, server := slotPair(t, newMemSlots(), 8, 64<<10)
+	start := time.Now()
+	for range 10 {
+		for _, c := range [][2]*Conn{{client, server}, {server, client}} {
+			c[0].Write([]byte("ping"))
+			if _, err := io.ReadFull(c[1], make([]byte, 4)); err != nil {
+				t.Fatal(err)
+			}
+		}
+	}
+	if took := time.Since(start); took > 2*time.Second {
+		t.Fatalf("10 round trips took %v", took)
+	}
+}
+
+// once nothing comes for the eager window only the heads are asked for, not
+// the segments that a reader fetches ahead while things come
+func TestSlotIdle(t *testing.T) {
+	store := newMemSlots()
+	client, server := slotPair(t, store, 8, 64<<10)
+	for _, c := range [][2]*Conn{{client, server}, {server, client}} {
+		c[0].Write([]byte("ping"))
+		if _, err := io.ReadFull(c[1], make([]byte, 4)); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	time.Sleep(200 * time.Millisecond)
+	store.mu.Lock()
+	before := store.reads
+	store.mu.Unlock()
+	time.Sleep(500 * time.Millisecond)
+	store.mu.Lock()
+	reads := store.reads - before
+	store.mu.Unlock()
+	// two heads, each asked for every 20 ms at most
+	if reads > 75 {
+		t.Fatalf("an idle session asked for slots %d times in 500 ms", reads)
+	}
+}
+
+type failingSlots struct {
+	*memSlots
+}
+
+// setSlot fails for segments, not for the error frame
+func (f failingSlots) setSlot(ctx context.Context, id, description string, body []byte) error {
+	if frame, ok := decodeSlot(description); ok && (frame.mode == slotInline || frame.mode == slotMedia) {
+		return io.ErrUnexpectedEOF
+	}
+	return f.memSlots.setSlot(ctx, id, description, body)
+}
+
+func TestSlotWriterFailure(t *testing.T) {
+	client, server := slotPair(t, failingSlots{newMemSlots()}, 2, 16<<10)
+	client.Write([]byte("lost"))
+	server.SetReadDeadline(time.Now().Add(5 * time.Second))
+	if _, err := server.Read(make([]byte, 10)); err == nil || err == io.EOF || errors.Is(err, os.ErrDeadlineExceeded) {
+		t.Fatalf("the reader got %v, not the failure of the writer", err)
+	}
+	for start := time.Now(); time.Since(start) < 5*time.Second; time.Sleep(time.Millisecond) {
+		if _, err := client.Write([]byte("more")); err != nil {
+			return
+		}
+	}
+	t.Fatal("Write did not fail")
+}
+
+type staleSlots struct {
+	*memSlots
+	mu     sync.Mutex
+	served map[string]bool
+}
+
+// readBody gives what a slot held before once, as a body read right after its
+// description may
+func (s *staleSlots) readBody(ctx context.Context, id string) ([]byte, error) {
+	s.mu.Lock()
+	first := !s.served[id]
+	s.served[id] = true
+	s.mu.Unlock()
+	if first {
+		return []byte("stale"), nil
+	}
+	return s.memSlots.readBody(ctx, id)
+}
+
+func TestSlotStaleBody(t *testing.T) {
+	client, server := slotPair(t, &staleSlots{memSlots: newMemSlots(), served: make(map[string]bool)}, 2, 64<<10)
+	payload := randomPayload(200 << 10)
+	errs := make(chan error, 1)
+	writeAll(client, payload, true, errs)
+	readAll(t, server, payload)
+}

transport/internet/xdrive/storage.go

@@ -43,11 +43,30 @@ func newStorage(streamSettings *internet.MemoryStreamConfig) (Storage, error) {
 		return sharedStorage(streamSettings, config, func() (Storage, error) {
 			return newTemplateStorage(streamSettings, config)
 		})
+	case "s3":
+		return sharedStorage(streamSettings, config, func() (Storage, error) {
+			return newS3Storage(streamSettings, config)
+		})
 	default:
 		return nil, errors.New("unsupported service: ", config.Service)
 	}
 }
 
+// sessionStorage returns the storage of one session, which takes connections
+// of XMUX until Close, with the token and cache of storage. Local storage has
+// no connections
+func sessionStorage(storage Storage) Storage {
+	switch s := storage.(type) {
+	case *driveStorage:
+		return s.session()
+	case *templateStorage:
+		return s.session()
+	case *s3Storage:
+		return s.session()
+	}
+	return storage
+}
+
 var (
 	sharedMu sync.Mutex
 	shared   = make(map[string]Storage)
@@ -55,6 +74,14 @@ var (
 
 func shareKey(streamSettings *internet.MemoryStreamConfig, config *Config) string {
 	parts := []string{config.Service, config.RemoteFolder}
+	if config.S3 != nil {
+		parts = append(parts, config.S3.Endpoint, s3Region(config.S3.Region), config.S3.Bucket)
+		if config.S3.PathStyle {
+			parts = append(parts, "path-style")
+		} else {
+			parts = append(parts, "virtual-hosted-style")
+		}
+	}
 	parts = append(parts, config.Secrets...)
 	if streamSettings != nil {
 		parts = append(parts, streamSettings.SecurityType)

transport/internet/xdrive/template.go

@@ -33,6 +33,14 @@ type opTemplate struct {
 	Headers    map[string]string `json:"headers"`
 	Body       string            `json:"body"`
 	NamesRegex string            `json:"namesRegex"`
+
+	// HrefPath makes the operation two-step, as in the Yandex Disk REST API: the first request
+	// answers with a JSON body, the URL found at HrefPath is then called with HrefMethod (GET by
+	// default), carrying the payload. The URL is used as given, with neither auth nor headers.
+	HrefPath   string `json:"hrefPath"`
+	HrefMethod string `json:"hrefMethod"`
+
+	presigned bool
 }
 
 type retryTemplate struct {
@@ -54,12 +62,20 @@ type storageTemplate struct {
 }
 
 type templateStorage struct {
-	tmpl    *storageTemplate
-	client  *http.Client
-	folder  string
-	secrets []string
-
+	*templateShared
+	// a session has a client and inflight of its own, see session
+	client   *http.Client
 	inflight chan struct{}
+	release  func()
+}
+
+// templateShared is what the sessions of a storage have in common
+type templateShared struct {
+	conns       *connPool
+	tmpl        *storageTemplate
+	tokenClient *http.Client
+	folder      string
+	secrets     []string
 
 	tokenMu     sync.Mutex
 	token       string
@@ -94,15 +110,35 @@ func newTemplateStorage(streamSettings *internet.MemoryStreamConfig, config *Con
 		conc = maxTemplateConcurrency
 	}
 
+	h1Hosts := new(sync.Map)
+	client := newServiceClient(context.Background(), h1Hosts, streamSettings, driveTimeout, conc)
 	return &templateStorage{
-		tmpl:     tmpl,
-		client:   newServiceClient(streamSettings, driveTimeout, conc),
-		folder:   config.RemoteFolder,
-		secrets:  config.Secrets,
+		templateShared: &templateShared{
+			conns: newConnPool(config.Xmux, func(connCtx context.Context) *http.Client {
+				return newServiceClient(connCtx, h1Hosts, streamSettings, driveTimeout, conc)
+			}),
+			tmpl:        tmpl,
+			tokenClient: client,
+			folder:      config.RemoteFolder,
+			secrets:     config.Secrets,
+		},
+		client:   client,
 		inflight: make(chan struct{}, conc),
 	}, nil
 }
 
+// session returns a storage for one session, over the connections of XMUX
+// until Close, with the token of s
+func (s *templateStorage) session() Storage {
+	transport := &sessionTransport{pool: s.conns}
+	return &templateStorage{
+		templateShared: s.templateShared,
+		client:         &http.Client{Transport: transport},
+		inflight:       make(chan struct{}, cap(s.inflight)),
+		release:        transport.Close,
+	}
+}
+
 const maxTemplateConcurrency = 256
 
 func (s *templateStorage) baseVars() map[string]string {
@@ -216,7 +252,7 @@ func (s *templateStorage) accessToken(ctx context.Context) (string, error) {
 	}
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 
-	resp, err := s.client.Do(req)
+	resp, err := s.tokenClient.Do(req)
 	if err != nil {
 		return "", errors.New("failed to fetch the token").Base(err)
 	}
@@ -262,6 +298,11 @@ func (s *templateStorage) do(ctx context.Context, op *opTemplate, vars map[strin
 	backoff := driveInitialBackoff
 	var lastErr error
 
+	url := op.URL
+	if !op.presigned {
+		url = subst(url, vars)
+	}
+
 	for attempt := 0; attempt < driveMaxAttempts; attempt++ {
 		if attempt > 0 {
 			select {
@@ -275,10 +316,14 @@ func (s *templateStorage) do(ctx context.Context, op *opTemplate, vars map[strin
 			}
 		}
 
-		authHeaders, err := s.authHeaders(ctx, vars)
-		if err != nil {
-			lastErr = err
-			continue
+		var authHeaders map[string]string
+		if !op.presigned {
+			headers, err := s.authHeaders(ctx, vars)
+			if err != nil {
+				lastErr = err
+				continue
+			}
+			authHeaders = headers
 		}
 
 		method := op.Method
@@ -290,7 +335,7 @@ func (s *templateStorage) do(ctx context.Context, op *opTemplate, vars map[strin
 		if body != nil {
 			reader = bytes.NewReader(body)
 		}
-		req, err := http.NewRequestWithContext(ctx, method, subst(op.URL, vars), reader)
+		req, err := http.NewRequestWithContext(ctx, method, url, reader)
 		if err != nil {
 			return 0, nil, errors.New("failed to build request").Base(err)
 		}
@@ -325,7 +370,7 @@ func (s *templateStorage) do(ctx context.Context, op *opTemplate, vars map[strin
 			continue
 		}
 
-		if resp.StatusCode == http.StatusUnauthorized && s.tmpl.Auth.Type == "oauth2" {
+		if resp.StatusCode == http.StatusUnauthorized && s.tmpl.Auth.Type == "oauth2" && !op.presigned {
 			s.invalidateToken()
 			lastErr = errors.New("the service rejected the token")
 			continue
@@ -339,6 +384,22 @@ func (s *templateStorage) do(ctx context.Context, op *opTemplate, vars map[strin
 	return 0, nil, lastErr
 }
 
+// run performs op, following its href when the operation is two-step.
+func (s *templateStorage) run(ctx context.Context, op *opTemplate, vars map[string]string, body []byte) (int, []byte, error) {
+	if op.HrefPath == "" {
+		return s.do(ctx, op, vars, body)
+	}
+	status, payload, err := s.do(ctx, op, vars, nil)
+	if err != nil || status < 200 || status >= 300 {
+		return status, payload, err
+	}
+	href := jsonString(payload, op.HrefPath)
+	if href == "" {
+		return 0, nil, errors.New("the response has no href at ", op.HrefPath)
+	}
+	return s.do(ctx, &opTemplate{Method: op.HrefMethod, URL: href, presigned: true}, vars, body)
+}
+
 func (s *templateStorage) Put(ctx context.Context, name string, data []byte) error {
 	vars := s.baseVars()
 	vars["name"] = s.storedName(name)
@@ -349,7 +410,7 @@ func (s *templateStorage) Put(ctx context.Context, name string, data []byte) err
 		body = []byte(subst(s.tmpl.Put.Body, vars))
 	}
 
-	status, payload, err := s.do(ctx, &s.tmpl.Put, vars, body)
+	status, payload, err := s.run(ctx, &s.tmpl.Put, vars, body)
 	if err != nil {
 		return err
 	}
@@ -363,7 +424,7 @@ func (s *templateStorage) Get(ctx context.Context, name string) ([]byte, error)
 	vars := s.baseVars()
 	vars["name"] = s.storedName(name)
 
-	status, payload, err := s.do(ctx, &s.tmpl.Get, vars, nil)
+	status, payload, err := s.run(ctx, &s.tmpl.Get, vars, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -381,7 +442,7 @@ func (s *templateStorage) Delete(ctx context.Context, name string) error {
 	vars := s.baseVars()
 	vars["name"] = s.storedName(name)
 
-	status, payload, err := s.do(ctx, &s.tmpl.Delete, vars, nil)
+	status, payload, err := s.run(ctx, &s.tmpl.Delete, vars, nil)
 	if err != nil {
 		return err
 	}
@@ -396,7 +457,7 @@ func (s *templateStorage) List(ctx context.Context, prefix string) ([]Entry, err
 	flat := s.storedName(prefix)
 	vars["prefix"] = flat
 
-	status, payload, err := s.do(ctx, &s.tmpl.List, vars, nil)
+	status, payload, err := s.run(ctx, &s.tmpl.List, vars, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -441,5 +502,8 @@ func (s *templateStorage) List(ctx context.Context, prefix string) ([]Entry, err
 }
 
 func (s *templateStorage) Close() error {
+	if s.release != nil {
+		s.release()
+	}
 	return nil
 }

transport/internet/xdrive/template_test.go

@@ -113,7 +113,7 @@ func templateSettings(store *fakeStore, auth map[string]interface{}, secrets []s
 		"delete":  map[string]interface{}{"method": "DELETE", "url": base + "/folder/{name}"},
 		"list": map[string]interface{}{
 			"method":     "PROPFIND",
-			"url":        base + "/folder/",
+			"url":        base + "/folder/?prefix={prefix}",
 			"namesRegex": `<d:href>/folder/([^<]+)</d:href>`,
 		},
 		"retry": map[string]interface{}{"status": []int{429, 500, 502, 503}},
@@ -297,6 +297,12 @@ func TestTemplateConcurrency(t *testing.T) {
 	if cap(storage.inflight) != 4 {
 		t.Fatalf("inflight cap is %d, want 4 from the template", cap(storage.inflight))
 	}
+	// and so has a session, of its own
+	session := storage.session().(*templateStorage)
+	defer session.Close()
+	if session.inflight == storage.inflight || cap(session.inflight) != 4 {
+		t.Fatalf("a session shares inflight or has cap %d, want 4", cap(session.inflight))
+	}
 }
 
 func TestTemplateConcurrencyDefault(t *testing.T) {
@@ -306,3 +312,113 @@ func TestTemplateConcurrencyDefault(t *testing.T) {
 		t.Fatalf("default inflight cap is %d, want %d", cap(storage.inflight), driveMaxInflight)
 	}
 }
+
+// hrefStore mimics the Yandex Disk REST API: upload and download answer with an href
+// to a presigned blob URL, which must be called without the API credentials.
+type hrefStore struct {
+	*fakeStore
+	blobAuth string
+}
+
+func newHrefStore(t *testing.T) *hrefStore {
+	t.Helper()
+
+	store := &hrefStore{fakeStore: &fakeStore{objects: make(map[string][]byte)}}
+	store.server = httptest.NewServer(http.HandlerFunc(store.handle))
+	t.Cleanup(store.server.Close)
+	return store
+}
+
+func (s *hrefStore) handle(w http.ResponseWriter, r *http.Request) {
+	if strings.HasPrefix(r.URL.Path, "/blob/") {
+		s.mu.Lock()
+		if auth := r.Header.Get("Authorization"); auth != "" {
+			s.blobAuth = auth
+		}
+		s.mu.Unlock()
+		r.URL.Path = "/folder/" + strings.TrimPrefix(r.URL.Path, "/blob/")
+		s.fakeStore.handle(w, r)
+		return
+	}
+	if r.Header.Get("Authorization") != "OAuth tok" {
+		w.WriteHeader(http.StatusUnauthorized)
+		return
+	}
+
+	name := r.URL.Query().Get("path")
+	switch r.URL.Path {
+	case "/upload":
+	case "/download":
+		s.mu.Lock()
+		_, ok := s.objects[name]
+		s.mu.Unlock()
+		if !ok {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+	default:
+		w.WriteHeader(http.StatusNotFound)
+		return
+	}
+	json.NewEncoder(w).Encode(map[string]interface{}{"href": s.server.URL + "/blob/" + name})
+}
+
+func hrefSettings(store *hrefStore) *internet.MemoryStreamConfig {
+	base := store.server.URL
+	settings := templateSettings(store.fakeStore, map[string]interface{}{
+		"type": "static", "header": map[string]interface{}{"Authorization": "OAuth {secret0}"},
+	}, []string{"tok"})
+	cfg := settings.ProtocolSettings.(*Config)
+	var tmpl map[string]interface{}
+	json.Unmarshal([]byte(cfg.Template), &tmpl)
+	tmpl["put"] = map[string]interface{}{"url": base + "/upload?path={name}", "hrefPath": "href", "hrefMethod": "PUT"}
+	tmpl["get"] = map[string]interface{}{"url": base + "/download?path={name}", "hrefPath": "href"}
+	tmpl["list"] = map[string]interface{}{"method": "PROPFIND", "url": base + "/blob/", "namesRegex": `<d:href>/folder/([^<]+)</d:href>`}
+	tmpl["delete"] = map[string]interface{}{"method": "DELETE", "url": base + "/blob/{name}"}
+	raw, _ := json.Marshal(tmpl)
+	cfg.Template = string(raw)
+	return settings
+}
+
+func TestTemplateTwoStep(t *testing.T) {
+	store := newHrefStore(t)
+	settings := hrefSettings(store)
+	storage, err := newTemplateStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newTemplateStorage: %v", err)
+	}
+	ctx := context.Background()
+
+	if err := storage.Put(ctx, "streams/abc/c2s/000000000.seg", []byte("hello")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+	data, err := storage.Get(ctx, "streams/abc/c2s/000000000.seg")
+	if err != nil {
+		t.Fatalf("Get: %v", err)
+	}
+	if string(data) != "hello" {
+		t.Fatalf("Get returned %q, want hello", data)
+	}
+	if _, err := storage.Get(ctx, "streams/abc/c2s/000000009.seg"); err != errNotFound {
+		t.Fatalf("Get of a missing object returned %v, want errNotFound", err)
+	}
+	if store.blobAuth != "" {
+		t.Fatalf("the presigned href received credentials %q", store.blobAuth)
+	}
+}
+
+func TestTemplateTwoStepTransport(t *testing.T) {
+	store := newHrefStore(t)
+	client, server, cleanup := pairWith(t, hrefSettings(store))
+	defer cleanup()
+
+	if _, err := client.Write([]byte("ping")); err != nil {
+		t.Fatalf("client write: %v", err)
+	}
+	expectRead(t, server, "ping")
+
+	if _, err := server.Write([]byte("pong")); err != nil {
+		t.Fatalf("server write: %v", err)
+	}
+	expectRead(t, client, "pong")
+}

transport/internet/xdrive/wal.go

@@ -230,6 +230,10 @@ func newWALReader(ctx context.Context, storage Storage, prefix string, p params)
 	return r
 }
 
+func (r *walReader) chunks() <-chan []byte {
+	return r.ch
+}
+
 func (r *walReader) Wake() {
 	select {
 	case r.wake <- struct{}{}:

transport/internet/xdrive/xdrive.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"crypto/rand"
 	"encoding/hex"
+	"encoding/json"
 	"fmt"
 	"strconv"
 	"strings"
@@ -87,6 +88,7 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 	if err != nil {
 		return nil, err
 	}
+	storage = sessionStorage(storage)
 
 	session, err := newSessionID()
 	if err != nil {
@@ -94,15 +96,33 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 		return nil, err
 	}
 
-	if err := storage.Put(ctx, announceName(session, time.Now()), nil); err != nil {
+	p := paramsFromConfig(config)
+	var announce []byte
+	var r ring
+	slots, ok := storage.(slotStore)
+	if ok {
+		if r, err = makeRing(ctx, slots, session, p); err == nil {
+			announce, _ = json.Marshal(r)
+		} else {
+			ok = false
+			errors.LogWarningInner(ctx, err, "failed to make the slots of session ", session, ", it goes in segments")
+		}
+	}
+
+	if err := storage.Put(ctx, announceName(session, time.Now()), announce); err != nil {
 		storage.Close()
 		return nil, errors.New("failed to announce session ", session).Base(err)
 	}
 
+	if ok {
+		errors.LogInfo(ctx, "opened session ", session, " in ", len(r.Up.Slots), " slots")
+		return newSlotConn(context.Background(), slots, r.Up, r.Down, p, func() {
+			storage.Close()
+		}), nil
+	}
 	errors.LogInfo(ctx, "opened session ", session)
-
 	return newConn(context.Background(), storage,
-		uplinkPrefix(session), downlinkPrefix(session), paramsFromConfig(config), func() {
+		uplinkPrefix(session), downlinkPrefix(session), p, func() {
 			storage.Close()
 		}), nil
 }
@@ -205,9 +225,8 @@ func (l *Listener) acceptPending(logCtx context.Context) (bool, error) {
 			continue
 		}
 		go l.drop(full)
-		errors.LogInfo(logCtx, "accepted session ", session)
 		accepted = true
-		l.addConn(l.newSessionConn(session))
+		l.addConn(l.newSessionConn(logCtx, session, listed.Inline))
 	}
 	return accepted, nil
 }
@@ -227,13 +246,24 @@ func (l *Listener) claim(session string) bool {
 	return true
 }
 
-func (l *Listener) newSessionConn(session string) *Conn {
-	return newConn(l.ctx, l.storage,
-		downlinkPrefix(session), uplinkPrefix(session), l.params, func() {
-			l.mu.Lock()
-			delete(l.active, session)
-			l.mu.Unlock()
-		})
+// newSessionConn takes a session in the slots that its announcement has, or
+// in segments if it has none
+func (l *Listener) newSessionConn(logCtx context.Context, session string, announce []byte) *Conn {
+	storage := sessionStorage(l.storage)
+	onClose := func() {
+		storage.Close()
+		l.mu.Lock()
+		delete(l.active, session)
+		l.mu.Unlock()
+	}
+	if slots, ok := storage.(slotStore); ok {
+		if r, ok := decodeRing(announce); ok {
+			errors.LogInfo(logCtx, "accepted session ", session, " in ", len(r.Down.Slots), " slots")
+			return newSlotConn(l.ctx, slots, r.Down, r.Up, l.params, onClose)
+		}
+	}
+	errors.LogInfo(logCtx, "accepted session ", session)
+	return newConn(l.ctx, storage, downlinkPrefix(session), uplinkPrefix(session), l.params, onClose)
 }
 
 func (l *Listener) collectLoop(logCtx context.Context) {

transport/internet/xdrive/xdrive_test.go

@@ -4,16 +4,21 @@ import (
 	"bytes"
 	"context"
 	"crypto/rand"
+	gotls "crypto/tls"
 	"io"
+	"net/http"
 	"os"
 	"strings"
+	"sync"
 	"sync/atomic"
 	"testing"
 	"time"
 
 	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/splithttp"
 	"github.com/xtls/xray-core/transport/internet/stat"
+	"github.com/xtls/xray-core/transport/internet/tls"
 )
 
 const testPatience = 30 * time.Second
@@ -581,3 +586,388 @@ func TestInlinePayload(t *testing.T) {
 		t.Fatalf("called Get %d times for an inline payload", got)
 	}
 }
+
+// runSessions opens n sessions at once, both ends in this process, passes data
+// both ways over each and closes them
+func runSessions(t *testing.T, streamSettings *internet.MemoryStreamConfig, n int) {
+	t.Helper()
+
+	accepted := make(chan stat.Connection, 1)
+	listener, err := Serve(context.Background(), net.LocalHostIP, net.Port(0), streamSettings, func(conn stat.Connection) {
+		accepted <- conn
+	})
+	if err != nil {
+		t.Fatalf("Serve: %v", err)
+	}
+	defer listener.Close()
+
+	var ends []stat.Connection
+	defer func() {
+		for _, end := range ends {
+			end.Close()
+		}
+	}()
+	for range n {
+		client, err := Dial(context.Background(), net.Destination{}, streamSettings)
+		if err != nil {
+			t.Fatalf("Dial: %v", err)
+		}
+		ends = append(ends, client)
+		select {
+		case peer := <-accepted:
+			ends = append(ends, peer)
+		case <-time.After(testPatience):
+			t.Fatal("listener did not accept the session")
+		}
+	}
+	for i := 0; i < len(ends); i += 2 {
+		if _, err := ends[i].Write([]byte("ping")); err != nil {
+			t.Fatalf("client write: %v", err)
+		}
+		expectRead(t, ends[i+1], "ping")
+		if _, err := ends[i+1].Write([]byte("pong")); err != nil {
+			t.Fatalf("server write: %v", err)
+		}
+		expectRead(t, ends[i], "pong")
+	}
+}
+
+// sessionEnd is the session and end of it that a request to the fake store
+// comes from, or "" for the listener and the token
+func sessionEnd(r *http.Request) string {
+	name := strings.TrimPrefix(r.URL.Path, "/folder/")
+	if r.Method == "PROPFIND" {
+		name = r.URL.Query().Get("prefix")
+	}
+	write := r.Method == http.MethodPut
+	parts := strings.Split(name, flatSeparator)
+	switch {
+	case len(parts) > 2 && parts[0] == streamsDir:
+		// each end writes its own direction and reads the other
+		if (parts[2] == uplinkDir) == write {
+			return parts[1] + " client"
+		}
+		return parts[1] + " server"
+	case len(parts) == 2 && parts[0] == sessionsDir && write:
+		_, session, _ := strings.Cut(parts[1], "-")
+		return session + " client"
+	}
+	return ""
+}
+
+// with "maxConcurrency" 1 every end of a session has a connection of its own,
+// with "maxConnections" the ends share that many, and the sessions after them
+// take the same ones again. The listener and the token use none of them, and
+// the sessions get the token once
+func TestXmuxConnections(t *testing.T) {
+	const n = 3
+	for _, c := range []struct {
+		name   string
+		xmux   *splithttp.XmuxConfig
+		conns  int
+		shared bool
+	}{
+		{"maxConcurrency", &splithttp.XmuxConfig{MaxConcurrency: &splithttp.RangeConfig{From: 1, To: 1}}, 2 * n, false},
+		{"maxConnections", &splithttp.XmuxConfig{MaxConnections: &splithttp.RangeConfig{From: 2, To: 2}}, 2, true},
+	} {
+		t.Run(c.name, func(t *testing.T) {
+			resetSharedStorage()
+			t.Cleanup(resetSharedStorage)
+
+			store := &fakeStore{objects: make(map[string][]byte), needAuth: "Bearer tok-fake"}
+			var (
+				mu    sync.Mutex
+				conns = make(map[string]map[string]bool)
+			)
+			server := newTLSServer(t, &gotls.Config{NextProtos: chromeALPN}, func(w http.ResponseWriter, r *http.Request) {
+				end := sessionEnd(r)
+				mu.Lock()
+				if conns[end] == nil {
+					conns[end] = make(map[string]bool)
+				}
+				conns[end][r.RemoteAddr] = true
+				mu.Unlock()
+				store.handle(w, r)
+			})
+			store.server = server.Server
+			settings := templateSettings(store, map[string]interface{}{
+				"type":     "oauth2",
+				"tokenUrl": server.URL + "/token",
+				"form":     map[string]interface{}{"grant_type": "refresh_token", "refresh_token": "{secret0}"},
+				"header":   map[string]interface{}{"Authorization": "Bearer {token}"},
+			}, []string{"refresh"})
+			settings.SecuritySettings = server.settings(&tls.Config{}).SecuritySettings
+			settings.ProtocolSettings.(*Config).Xmux = c.xmux
+
+			runSessions(t, settings, n)
+			mu.Lock()
+			first := conns
+			conns = make(map[string]map[string]bool)
+			mu.Unlock()
+			dialed := server.conns.Load()
+			runSessions(t, settings, n)
+			if got := server.conns.Load(); got != dialed {
+				t.Errorf("the next %d sessions dialed %d connections", n, got-dialed)
+			}
+
+			owner := make(map[string]string)
+			for end, addrs := range first {
+				if end == "" {
+					continue
+				}
+				if len(addrs) != 1 {
+					t.Errorf("%s used %d connections", end, len(addrs))
+				}
+				for addr := range addrs {
+					if owner[addr] != "" && !c.shared {
+						t.Errorf("%s and %s shared a connection", end, owner[addr])
+					}
+					owner[addr] = end
+				}
+			}
+			if len(owner) != c.conns {
+				t.Errorf("%d sessions had %d connections, want %d", 2*n, len(owner), c.conns)
+			}
+			for addr := range first[""] {
+				if owner[addr] != "" {
+					t.Errorf("the listener or the token went over the connection of %s", owner[addr])
+				}
+			}
+			store.mu.Lock()
+			defer store.mu.Unlock()
+			if store.tokens != 1 {
+				t.Errorf("the sessions got the token %d times", store.tokens)
+			}
+		})
+	}
+}
+
+func TestDriveXmuxConnections(t *testing.T) {
+	drive := newFakeDrive(t)
+	server := newTLSServer(t, &gotls.Config{NextProtos: chromeALPN}, drive.server.Config.Handler.ServeHTTP)
+	driveTokenURL = server.URL + "/token"
+	driveFilesURL = server.URL + "/files"
+	driveUploadURL = server.URL + "/upload"
+	settings := driveSettings()
+	settings.SecuritySettings = server.settings(&tls.Config{}).SecuritySettings
+	settings.ProtocolSettings.(*Config).Xmux = &splithttp.XmuxConfig{MaxConnections: &splithttp.RangeConfig{From: 3, To: 3}}
+
+	runSessions(t, settings, 3)
+	if got := server.conns.Load(); got != 4 {
+		t.Errorf("6 ends of sessions with 3 connections and the listener took %d connections", got)
+	}
+
+	drive.mu.Lock()
+	defer drive.mu.Unlock()
+	if drive.tokens != 1 {
+		t.Errorf("6 ends of sessions got the token %d times", drive.tokens)
+	}
+}
+
+// a session knows the hosts that answered the storage over h1, the polling of
+// the listener for one, so it sends requests in a row over one connection, not
+// first over one for h2 that then stays idle, and parallel ones over more
+func TestSessionKnowsHTTP1Hosts(t *testing.T) {
+	check := func(name string, server *tlsServer, storage Storage) {
+		put := func(s Storage, names ...string) {
+			for _, n := range names {
+				if err := s.Put(context.Background(), "streams/abc/c2s/"+n, []byte("x")); err != nil {
+					t.Errorf("%s: Put: %v", name, err)
+				}
+			}
+		}
+		put(storage, "a", "b")
+		before := server.conns.Load()
+		session := sessionStorage(storage)
+		defer session.Close()
+		put(session, "c", "d")
+		if n := server.conns.Load() - before; n != 1 {
+			t.Errorf("%s: 2 requests in a row of a session over h1 took %d connections", name, n)
+		}
+
+		before = server.conns.Load()
+		var wg sync.WaitGroup
+		for _, n := range []string{"e", "f", "g", "h"} {
+			wg.Go(func() { put(session, n) })
+		}
+		wg.Wait()
+		if server.conns.Load() == before {
+			t.Errorf("%s: 4 parallel requests of a session over h1 took one connection", name)
+		}
+	}
+	slow := func(next http.HandlerFunc) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			time.Sleep(20 * time.Millisecond)
+			next(w, r)
+		}
+	}
+
+	store := &fakeStore{objects: make(map[string][]byte)}
+	server := newTLSServer(t, &gotls.Config{NextProtos: []string{"http/1.1"}}, slow(store.handle))
+	store.server = server.Server
+	settings := templateSettings(store, map[string]interface{}{"type": "none"}, nil)
+	settings.SecuritySettings = server.settings(&tls.Config{}).SecuritySettings
+	template, err := newTemplateStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newTemplateStorage: %v", err)
+	}
+	check("template", server, template)
+
+	drive := newFakeDrive(t)
+	server = newTLSServer(t, &gotls.Config{NextProtos: []string{"http/1.1"}}, slow(drive.server.Config.Handler.ServeHTTP))
+	driveTokenURL = server.URL + "/token"
+	driveFilesURL = server.URL + "/files"
+	settings = driveSettings()
+	settings.SecuritySettings = server.settings(&tls.Config{}).SecuritySettings
+	google, err := newDriveStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	check("drive", server, google)
+}
+
+// with "hMaxRequestTimes" a session moves on to a new connection after that
+// many requests, and the old one closes once the requests on it end, not before
+func TestXmuxRequestLimit(t *testing.T) {
+	store := &fakeStore{objects: make(map[string][]byte)}
+	arrived := make(chan struct{}, 1)
+	release := make(chan struct{})
+	server := newTLSServer(t, &gotls.Config{NextProtos: chromeALPN}, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodGet {
+			arrived <- struct{}{}
+			<-release
+		}
+		store.handle(w, r)
+	})
+	store.server = server.Server
+	settings := templateSettings(store, map[string]interface{}{"type": "none"}, nil)
+	settings.SecuritySettings = server.settings(&tls.Config{}).SecuritySettings
+	settings.ProtocolSettings.(*Config).Xmux = &splithttp.XmuxConfig{HMaxRequestTimes: &splithttp.RangeConfig{From: 3, To: 3}}
+	storage, err := newTemplateStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newTemplateStorage: %v", err)
+	}
+	session := sessionStorage(storage)
+	defer session.Close()
+	put := func(names ...string) {
+		for _, name := range names {
+			if err := session.Put(context.Background(), "streams/abc/c2s/"+name, []byte("x")); err != nil {
+				t.Fatalf("Put: %v", err)
+			}
+		}
+	}
+
+	put("a")
+	got := make(chan error, 1)
+	go func() {
+		_, err := session.Get(context.Background(), "streams/abc/c2s/a")
+		got <- err
+	}()
+	<-arrived
+	put("b", "c")
+	if n := server.conns.Load(); n != 2 {
+		t.Errorf("4 requests with 3 to a connection took %d connections", n)
+	}
+	if server.closed.Load() != 0 {
+		t.Error("the first connection closed under a request")
+	}
+	close(release)
+	if err := <-got; err != nil {
+		t.Errorf("Get on the first connection: %v", err)
+	}
+	waitFor(t, "the first connection to close", func() bool { return server.closed.Load() == 1 })
+
+	put("d", "e", "f")
+	if n := server.conns.Load(); n != 3 {
+		t.Errorf("7 requests with 3 to a connection took %d connections", n)
+	}
+	waitFor(t, "the second connection to close", func() bool { return server.closed.Load() == 2 })
+}
+
+// a session that fails to announce itself lets go of its connection, which the
+// next one takes with "maxConcurrency" 1
+func TestFailedDialReleasesConnection(t *testing.T) {
+	resetSharedStorage()
+	t.Cleanup(resetSharedStorage)
+
+	store := &fakeStore{objects: make(map[string][]byte)}
+	var refuse atomic.Bool
+	refuse.Store(true)
+	server := newTLSServer(t, &gotls.Config{NextProtos: chromeALPN}, func(w http.ResponseWriter, r *http.Request) {
+		if refuse.Load() {
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+		store.handle(w, r)
+	})
+	store.server = server.Server
+	settings := templateSettings(store, map[string]interface{}{"type": "none"}, nil)
+	settings.SecuritySettings = server.settings(&tls.Config{}).SecuritySettings
+	settings.ProtocolSettings.(*Config).Xmux = &splithttp.XmuxConfig{MaxConcurrency: &splithttp.RangeConfig{From: 1, To: 1}}
+
+	if _, err := Dial(context.Background(), net.Destination{}, settings); err == nil {
+		t.Fatal("Dial announced a session that the service refused")
+	}
+	refuse.Store(false)
+	conn, err := Dial(context.Background(), net.Destination{}, settings)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer conn.Close()
+	if n := server.conns.Load(); n != 1 {
+		t.Errorf("a failed Dial and the next took %d connections", n)
+	}
+}
+
+// a session gets the token over a connection of the storage, not over one of
+// XMUX
+func TestSessionTokenConnection(t *testing.T) {
+	check := func(name string, server *tlsServer, storage Storage) {
+		session := sessionStorage(storage)
+		defer session.Close()
+		if err := session.Put(context.Background(), "sessions/abc", nil); err != nil {
+			t.Fatalf("%s: Put: %v", name, err)
+		}
+		if n := server.conns.Load(); n != 2 {
+			t.Errorf("%s: the token and a Put of a session took %d connections, want 2", name, n)
+		}
+	}
+
+	store := &fakeStore{objects: make(map[string][]byte), needAuth: "Bearer tok-fake"}
+	server := newTLSServer(t, &gotls.Config{NextProtos: chromeALPN}, store.handle)
+	store.server = server.Server
+	settings := templateSettings(store, map[string]interface{}{
+		"type":     "oauth2",
+		"tokenUrl": server.URL + "/token",
+		"header":   map[string]interface{}{"Authorization": "Bearer {token}"},
+	}, nil)
+	settings.SecuritySettings = server.settings(&tls.Config{}).SecuritySettings
+	template, err := newTemplateStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newTemplateStorage: %v", err)
+	}
+	check("template", server, template)
+
+	drive := newFakeDrive(t)
+	server = newTLSServer(t, &gotls.Config{NextProtos: chromeALPN}, drive.server.Config.Handler.ServeHTTP)
+	driveTokenURL = server.URL + "/token"
+	driveFilesURL = server.URL + "/files"
+	settings = driveSettings()
+	settings.SecuritySettings = server.settings(&tls.Config{}).SecuritySettings
+	google, err := newDriveStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	check("drive", server, google)
+}
+
+// local storage has no connections to keep apart
+func TestLocalSessionStorage(t *testing.T) {
+	storage, err := newLocalStorage(t.TempDir())
+	if err != nil {
+		t.Fatalf("newLocalStorage: %v", err)
+	}
+	if sessionStorage(storage) != Storage(storage) {
+		t.Fatal("a session of local storage got a storage of its own")
+	}
+}