Preserve startup error when browser dialer cleanup fails

Agent-Logs-Url: https://github.com/XTLS/Xray-core/sessions/b8c640ab-f93c-4609-8e34-a8e14e2be9e7

Co-authored-by: RPRX <63339210+RPRX@users.noreply.github.com>

core/xray.go

@@ -18,6 +18,7 @@ import (
 	"github.com/xtls/xray-core/features/routing"
 	"github.com/xtls/xray-core/features/stats"
 	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/browser_dialer"
 )
 
 // Server is an instance of Xray. At any time, there must be at most one Server instance running.
@@ -262,6 +263,9 @@ func (s *Instance) Close() error {
 	s.running = false
 
 	var errs []interface{}
+	if err := browser_dialer.StopCollectedDialerProxyURLs(); err != nil {
+		errs = append(errs, err)
+	}
 	for _, f := range s.features {
 		if err := f.Close(); err != nil {
 			errs = append(errs, err)
@@ -385,9 +389,16 @@ func (s *Instance) Start() error {
 	s.statusLock.Lock()
 	defer s.statusLock.Unlock()
 
+	if err := browser_dialer.StartCollectedDialerProxyURLs(); err != nil {
+		return err
+	}
 	s.running = true
 	for _, f := range s.features {
 		if err := f.Start(); err != nil {
+			s.running = false
+			if stopErr := browser_dialer.StopCollectedDialerProxyURLs(); stopErr != nil {
+				return errors.New("browser dialer cleanup after startup failure also failed: ", stopErr).Base(err)
+			}
 			return err
 		}
 	}

infra/conf/transport_internet.go

@@ -21,6 +21,7 @@ import (
 	"github.com/xtls/xray-core/common/platform/filesystem"
 	"github.com/xtls/xray-core/common/serial"
 	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/browser_dialer"
 	"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/header/dns"
@@ -1970,6 +1971,35 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 		}
 		config.ProtocolName = protocol
 	}
+	if c.SocketSettings != nil && c.SocketSettings.DialerProxy != "" {
+		if browser_dialer.IsBrowserDialerProxy(c.SocketSettings.DialerProxy) {
+			if config.ProtocolName != "websocket" && config.ProtocolName != "splithttp" {
+				return nil, errors.New("dialerProxy ", c.SocketSettings.DialerProxy, " only supports websocket or splithttp")
+			}
+			if strings.EqualFold(c.Security, "reality") {
+				return nil, errors.New("dialerProxy ", c.SocketSettings.DialerProxy, " does not support REALITY")
+			}
+			if config.ProtocolName == "splithttp" {
+				splitHTTPSettings := c.SplitHTTPSettings
+				if c.XHTTPSettings != nil {
+					splitHTTPSettings = c.XHTTPSettings
+				}
+				if splitHTTPSettings != nil {
+					splitHTTPSettingsCopy := *splitHTTPSettings
+					hs, err := splitHTTPSettingsCopy.Build()
+					if err != nil {
+						return nil, errors.New("failed to build XHTTP config for browser dialer validation").Base(err)
+					}
+					if splitHTTPConfig, ok := hs.(*splithttp.Config); ok && splitHTTPConfig.Mode != "auto" && splitHTTPConfig.Mode != "packet-up" {
+						return nil, errors.New("dialerProxy ", c.SocketSettings.DialerProxy, " only supports XHTTP modes \"auto\" or \"packet-up\", got: \"", splitHTTPConfig.Mode, "\"")
+					}
+				}
+			}
+			if err := browser_dialer.RegisterDialerProxyURL(c.SocketSettings.DialerProxy); err != nil {
+				return nil, errors.New("failed to collect browser dialer URL").Base(err)
+			}
+		}
+	}
 
 	switch strings.ToLower(c.Security) {
 	case "", "none":

infra/conf/xray.go

@@ -15,6 +15,7 @@ import (
 	"github.com/xtls/xray-core/common/serial"
 	core "github.com/xtls/xray-core/core"
 	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/browser_dialer"
 )
 
 var (
@@ -437,7 +438,6 @@ func (c *Config) Override(o *Config, fn string) {
 	if o.Geodata != nil {
 		c.Geodata = o.Geodata
 	}
-
 	// update the Inbound in slice if the only one in override config has same tag
 	if len(o.InboundConfigs) > 0 {
 		for i := range o.InboundConfigs {
@@ -604,6 +604,9 @@ func (c *Config) Build() (*core.Config, error) {
 	if len(c.Transport) > 0 {
 		return nil, errors.PrintRemovedFeatureError("Global transport config", "streamSettings in inbounds and outbounds")
 	}
+	if err := browser_dialer.BeginCollectingDialerProxyURLs(); err != nil {
+		return nil, err
+	}
 
 	for _, rawInboundConfig := range inbounds {
 		ic, err := rawInboundConfig.Build()
@@ -626,6 +629,9 @@ func (c *Config) Build() (*core.Config, error) {
 		}
 		config.Outbound = append(config.Outbound, oc)
 	}
+	if err := browser_dialer.ConfigureCollectedDialerProxyURLs(); err != nil {
+		return nil, errors.New("failed to configure browser dialer").Base(err)
+	}
 
 	return config, nil
 }

transport/internet/browser_dialer/dialer.go

@@ -1,101 +1,33 @@
 package browser_dialer
 
 import (
-	"bytes"
-	"context"
 	_ "embed"
 	"encoding/base64"
 	"encoding/json"
 	"net/http"
-	"sync"
-	"time"
 
 	"github.com/gorilla/websocket"
 	"github.com/xtls/xray-core/common/errors"
-	"github.com/xtls/xray-core/common/platform"
-	"github.com/xtls/xray-core/common/uuid"
 )
 
 //go:embed dialer.html
 var webpage []byte
 
 type task struct {
-	Method string `json:"method"`
-	URL    string `json:"url"`
-	Extra  any    `json:"extra,omitempty"`
-	StreamResponse bool `json:"streamResponse"`
-}
-
-var conns chan *websocket.Conn
-var server *http.Server
-var mu sync.Mutex
-
-var upgrader = &websocket.Upgrader{
-	ReadBufferSize:   0,
-	WriteBufferSize:  0,
-	HandshakeTimeout: time.Second * 4,
-	CheckOrigin: func(r *http.Request) bool {
-		return true
-	},
-}
-
-// Used by external projects when using xray as a go module
-func Reload() {
-	addr := platform.NewEnvFlag(platform.BrowserDialerAddress).GetValue(func() string { return "" })
-	mu.Lock()
-	defer mu.Unlock()
-
-	if server != nil {
-		server.Close()
-	}
-	if HasBrowserDialer() {
-		for len(conns) > 0 {
-			select {
-				case c := <-conns:
-					c.Close()
-				default:
-			}
-		}
-		conns = nil
-	}
-	if addr != "" {
-		token := uuid.New()
-		csrfToken := token.String()
-		webpage := bytes.ReplaceAll(webpage, []byte("csrfToken"), []byte(csrfToken))
-		conns = make(chan *websocket.Conn, 256)
-		server = &http.Server{
-			Addr: addr,
-			Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-				if r.URL.Path == "/websocket" {
-					if r.URL.Query().Get("token") == csrfToken {
-						if conn, err := upgrader.Upgrade(w, r, nil); err == nil {
-							conns <- conn
-						} else {
-							errors.LogError(context.Background(), "Browser dialer http upgrade unexpected error")
-						}
-					}
-				} else {
-					w.Header().Set("Access-Control-Allow-Origin", "*");
-					w.Write(webpage)
-				}
-			}),
-		}
-		go server.ListenAndServe()
-	}
-}
-
-func HasBrowserDialer() bool {
-	return conns != nil
+	Method         string `json:"method"`
+	URL            string `json:"url"`
+	Extra          any    `json:"extra,omitempty"`
+	StreamResponse bool   `json:"streamResponse"`
 }
 
 type webSocketExtra struct {
 	Protocol string `json:"protocol,omitempty"`
 }
 
-func DialWS(uri string, ed []byte) (*websocket.Conn, error) {
+func DialWSWithAddress(addr string, uri string, ed []byte) (*websocket.Conn, error) {
 	task := task{
-		Method: "WS",
-		URL:    uri,
+		Method:         "WS",
+		URL:            uri,
 		StreamResponse: true,
 	}
 
@@ -105,7 +37,7 @@ func DialWS(uri string, ed []byte) (*websocket.Conn, error) {
 		}
 	}
 
-	return dialTask(task)
+	return dialTaskWithAddress(addr, task)
 }
 
 type httpExtra struct {
@@ -142,30 +74,26 @@ func httpExtraFromHeadersAndCookies(headers http.Header, cookies []*http.Cookie)
 	return &extra
 }
 
-func DialGet(uri string, headers http.Header, cookies []*http.Cookie) (*websocket.Conn, error) {
+func DialGetWithAddress(addr string, uri string, headers http.Header, cookies []*http.Cookie) (*websocket.Conn, error) {
 	task := task{
-		Method: "GET",
-		URL:    uri,
-		Extra:  httpExtraFromHeadersAndCookies(headers, cookies),
+		Method:         "GET",
+		URL:            uri,
+		Extra:          httpExtraFromHeadersAndCookies(headers, cookies),
 		StreamResponse: true,
 	}
 
-	return dialTask(task)
+	return dialTaskWithAddress(addr, task)
 }
 
-func DialPacket(method string, uri string, headers http.Header, cookies []*http.Cookie, payload []byte) error {
-	return dialWithBody(method, uri, headers, cookies, payload)
-}
-
-func dialWithBody(method string, uri string, headers http.Header, cookies []*http.Cookie, payload []byte) error {
+func DialPacketWithAddress(addr string, method string, uri string, headers http.Header, cookies []*http.Cookie, payload []byte) error {
 	task := task{
-		Method: method,
-		URL:    uri,
-		Extra:  httpExtraFromHeadersAndCookies(headers, cookies),
+		Method:         method,
+		URL:            uri,
+		Extra:          httpExtraFromHeadersAndCookies(headers, cookies),
 		StreamResponse: false,
 	}
 
-	conn, err := dialTask(task)
+	conn, err := dialTaskWithAddress(addr, task)
 	if err != nil {
 		return err
 	}
@@ -184,12 +112,21 @@ func dialWithBody(method string, uri string, headers http.Header, cookies []*htt
 	return nil
 }
 
-func dialTask(task task) (*websocket.Conn, error) {
+func dialTaskWithAddress(addr string, task task) (*websocket.Conn, error) {
 	data, err := json.Marshal(task)
 	if err != nil {
 		return nil, err
 	}
 
+	if addr == "" {
+		return nil, errors.New("browser dialer is not configured; set sockopt.dialerProxy to browser://host:port/uuid")
+	}
+	dialer, err := getDialerByAddress(addr)
+	if err != nil {
+		return nil, err
+	}
+	conns := dialer.conns
+
 	var conn *websocket.Conn
 	for {
 		conn = <-conns
@@ -218,8 +155,3 @@ func CheckOK(conn *websocket.Conn) error {
 
 	return nil
 }
-
-func init() {
-	Reload()
-}
-

transport/internet/browser_dialer/dialer.html

@@ -10,7 +10,7 @@
 		// Enable a much more aggressive JIT for performance gains
 
 		// Copyright (c) 2021 XRAY. Mozilla Public License 2.0.
-		let url = "ws://" + window.location.host + "/websocket?token=csrfToken";
+		let url = "ws://" + window.location.host + "/dialerPath";
 		let clientIdleCount = 0;
 		let upstreamGetCount = 0;
 		let upstreamWsCount = 0;
@@ -67,7 +67,7 @@
 			}
 			clientIdleCount += 1;
 			console.log("Prepare", url);
-			let ws = new WebSocket(url);
+			let ws = new WebSocket(url, "browser-dialer");
 			// arraybuffer is significantly faster in chrome than default
 			// blob, tested with chrome 123
 			ws.binaryType = "arraybuffer";

transport/internet/browser_dialer/manager.go

@@ -0,0 +1,318 @@
+package browser_dialer
+
+import (
+	"bytes"
+	"context"
+	stderrors "errors"
+	"net"
+	"net/http"
+	"net/url"
+	pathlib "path"
+	"strings"
+	"time"
+
+	"github.com/gorilla/websocket"
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/platform"
+	"github.com/xtls/xray-core/common/serial"
+	"github.com/xtls/xray-core/common/uuid"
+)
+
+var dialersByAddress = map[string]*dialerInstance{}
+var serversByListenAddr = map[string]*dialerServer{}
+var initialized bool
+var pendingURLs map[string]struct{}
+
+const browserDialerSubprotocol = "browser-dialer"
+
+var upgrader = &websocket.Upgrader{
+	ReadBufferSize:   0,
+	WriteBufferSize:  0,
+	HandshakeTimeout: time.Second * 4,
+	CheckOrigin: func(r *http.Request) bool {
+		return true
+	},
+}
+
+func CheckLegacyEnv() error {
+	envAddress := platform.NewEnvFlag(platform.BrowserDialerAddress).GetValue(func() string { return "" })
+	if envAddress == "" {
+		return nil
+	}
+	return errors.PrintRemovedFeatureError("env "+platform.BrowserDialerAddress, "sockopt.dialerProxy with browser://host:port/uuid")
+}
+
+func IsBrowserDialerProxy(raw string) bool {
+	_, _, ok := parseBrowserDialerAddress(raw)
+	return ok
+}
+
+func BeginCollectingDialerProxyURLs() error {
+	if initialized {
+		return errors.New("browser dialer does not support dynamic add/remove; restart is required after changing configuration")
+	}
+	if err := CheckLegacyEnv(); err != nil {
+		return err
+	}
+	pendingURLs = map[string]struct{}{}
+	return nil
+}
+
+func RegisterDialerProxyURL(raw string) error {
+	if !IsBrowserDialerProxy(raw) {
+		return nil
+	}
+	if pendingURLs == nil {
+		return errors.New("browser dialer url collection is not initialized")
+	}
+	pendingURLs[raw] = struct{}{}
+	return nil
+}
+
+func ConfigureCollectedDialerProxyURLs() error {
+	if initialized {
+		return errors.New("browser dialer does not support dynamic add/remove; restart is required after changing configuration")
+	}
+	if err := CheckLegacyEnv(); err != nil {
+		return err
+	}
+	listenAddrByPort := make(map[string]string, len(pendingURLs))
+	for browserDialerURL := range pendingURLs {
+		listenAddr, _, ok := parseBrowserDialerAddress(browserDialerURL)
+		if !ok {
+			return errors.New("invalid browser dialer url: ", browserDialerURL)
+		}
+		_, port, err := net.SplitHostPort(listenAddr)
+		if err != nil {
+			return errors.New("invalid browser dialer listen address: ", listenAddr)
+		}
+		if existingAddr, found := listenAddrByPort[port]; found && existingAddr != listenAddr {
+			return errors.New("browser dialer cannot use the same port with a different listen address: ", existingAddr, " and ", listenAddr)
+		}
+		listenAddrByPort[port] = listenAddr
+	}
+	for existingAddr := range serversByListenAddr {
+		_, existingPort, splitErr := net.SplitHostPort(existingAddr)
+		if splitErr != nil {
+			continue
+		}
+		if newAddr, found := listenAddrByPort[existingPort]; found && newAddr != existingAddr {
+			return errors.New("browser dialer cannot use the same port with a different listen address: ", existingAddr, " and ", newAddr)
+		}
+	}
+	for browserDialerURL := range pendingURLs {
+		if _, err := ensureDialerWithAddress(browserDialerURL); err != nil {
+			return errors.New("failed to initialize browser dialer listener for url ", browserDialerURL).Base(err)
+		}
+	}
+	return nil
+}
+
+// StartCollectedDialerProxyURLs starts listeners for browser dialer URLs
+// prepared by ConfigureCollectedDialerProxyURLs.
+// Subsequent calls after successful initialization return nil.
+func StartCollectedDialerProxyURLs() error {
+	if initialized {
+		return nil
+	}
+	for listenAddr, server := range serversByListenAddr {
+		if err := server.start(); err != nil {
+			return errors.New("failed to start browser dialer listener on ", listenAddr).Base(err)
+		}
+	}
+	initialized = true
+	return nil
+}
+
+func StopCollectedDialerProxyURLs() error {
+	var stopErrs []string
+	for listenAddr, server := range serversByListenAddr {
+		if err := server.stop(); err != nil {
+			stopErrs = append(stopErrs, serial.Concat("failed to stop browser dialer listener on ", listenAddr, ": ", err))
+		}
+	}
+	dialersByAddress = map[string]*dialerInstance{}
+	serversByListenAddr = map[string]*dialerServer{}
+	pendingURLs = nil
+	initialized = false
+	if len(stopErrs) > 0 {
+		return errors.New(strings.Join(stopErrs, "; "))
+	}
+	return nil
+}
+
+type dialerInstance struct {
+	conns chan *websocket.Conn
+	page  []byte
+}
+
+type dialerServer struct {
+	server     *http.Server
+	pageRoutes map[string]*dialerInstance
+	started    bool
+}
+
+func parseBrowserDialerAddress(addr string) (string, string, bool) {
+	if addr == "" {
+		return "", "", false
+	}
+
+	parsedAddr, err := url.Parse(addr)
+	if err != nil || !strings.EqualFold(parsedAddr.Scheme, "browser") || parsedAddr.Host == "" || parsedAddr.Path == "" || parsedAddr.RawQuery != "" || parsedAddr.Fragment != "" {
+		return "", "", false
+	}
+	listenAddr := parsedAddr.Host
+	if _, _, err := net.SplitHostPort(listenAddr); err != nil {
+		return "", "", false
+	}
+	path := strings.TrimSuffix(parsedAddr.Path, "/")
+	if !strings.HasPrefix(path, "/") {
+		path = "/" + path
+	}
+	cleanPath := pathlib.Clean(path)
+	if cleanPath == "." || cleanPath == "/" || cleanPath != path {
+		return "", "", false
+	}
+	if strings.Count(cleanPath, "/") != 1 {
+		return "", "", false
+	}
+	id := strings.TrimPrefix(cleanPath, "/")
+	id = strings.ToLower(id)
+	parsedUUID, err := uuid.ParseString(id)
+	if err != nil || parsedUUID.String() != id {
+		return "", "", false
+	}
+	return listenAddr, "/" + id, true
+}
+
+func newDialerServer(listenAddr string) (*dialerServer, error) {
+	dialer := &dialerServer{
+		pageRoutes: make(map[string]*dialerInstance),
+	}
+	dialer.server = &http.Server{
+		Addr: listenAddr,
+		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			pageDialer := dialer.pageRoutes[r.URL.Path]
+
+			if pageDialer != nil && websocket.IsWebSocketUpgrade(r) {
+				ok := false
+				for _, protocol := range websocket.Subprotocols(r) {
+					if protocol == browserDialerSubprotocol {
+						ok = true
+						break
+					}
+				}
+				if !ok {
+					closeConnection(w)
+					return
+				}
+				if conn, err := upgrader.Upgrade(w, r, http.Header{"Sec-WebSocket-Protocol": []string{browserDialerSubprotocol}}); err == nil {
+					pageDialer.conns <- conn
+				} else {
+					errors.LogError(context.Background(), "Browser dialer http upgrade unexpected error: ", err)
+				}
+				return
+			}
+
+			if pageDialer != nil {
+				w.Header().Set("Access-Control-Allow-Origin", "*")
+				if _, err := w.Write(pageDialer.page); err != nil {
+					errors.LogError(context.Background(), "Browser dialer http page write unexpected error: ", err)
+				}
+				return
+			}
+
+			closeConnection(w)
+		}),
+	}
+	return dialer, nil
+}
+
+func (d *dialerServer) start() error {
+	if d.started {
+		return nil
+	}
+	listener, err := net.Listen("tcp", d.server.Addr)
+	if err != nil {
+		return err
+	}
+	d.started = true
+	go func() {
+		if err := d.server.Serve(listener); err != nil && !stderrors.Is(err, http.ErrServerClosed) {
+			errors.LogError(context.Background(), "Browser dialer http server unexpected error on ", d.server.Addr, ": ", err)
+		}
+	}()
+	return nil
+}
+
+func (d *dialerServer) stop() error {
+	if !d.started {
+		return nil
+	}
+	d.started = false
+	return d.server.Close()
+}
+
+func closeConnection(w http.ResponseWriter) {
+	hijacker, ok := w.(http.Hijacker)
+	if !ok {
+		return
+	}
+	conn, _, err := hijacker.Hijack()
+	if err != nil {
+		return
+	}
+	conn.Close()
+}
+
+func getDialerByAddress(addr string) (*dialerInstance, error) {
+	listenAddr, path, ok := parseBrowserDialerAddress(addr)
+	if !ok {
+		return nil, errors.New("invalid browser dialer url: ", addr)
+	}
+	key := listenAddr + path
+	if dialer, found := dialersByAddress[key]; found {
+		return dialer, nil
+	}
+	return nil, errors.New("browser dialer is not configured for url: ", addr)
+}
+
+func ensureDialerWithAddress(addr string) (*dialerInstance, error) {
+	listenAddr, path, ok := parseBrowserDialerAddress(addr)
+	if !ok {
+		return nil, errors.New("invalid browser dialer url: ", addr)
+	}
+	_, port, err := net.SplitHostPort(listenAddr)
+	if err != nil {
+		return nil, errors.New("invalid browser dialer listen address: ", listenAddr)
+	}
+
+	key := listenAddr + path
+	if dialer, found := dialersByAddress[key]; found {
+		return dialer, nil
+	}
+
+	server, found := serversByListenAddr[listenAddr]
+	if !found {
+		for existingAddr := range serversByListenAddr {
+			_, existingPort, splitErr := net.SplitHostPort(existingAddr)
+			if splitErr == nil && existingPort == port {
+				return nil, errors.New("browser dialer cannot use the same port with a different listen address: ", existingAddr, " and ", listenAddr)
+			}
+		}
+		newServer, serverErr := newDialerServer(listenAddr)
+		if serverErr != nil {
+			return nil, serverErr
+		}
+		server = newServer
+		serversByListenAddr[listenAddr] = server
+	}
+
+	dialer := &dialerInstance{
+		conns: make(chan *websocket.Conn, 256),
+		page:  bytes.ReplaceAll(webpage, []byte("dialerPath"), []byte(strings.TrimPrefix(path, "/"))),
+	}
+	dialersByAddress[key] = dialer
+	server.pageRoutes[path] = dialer
+	return dialer, nil
+}

transport/internet/dialer.go

@@ -14,6 +14,7 @@ import (
 	"github.com/xtls/xray-core/features/dns"
 	"github.com/xtls/xray-core/features/outbound"
 	"github.com/xtls/xray-core/transport"
+	"github.com/xtls/xray-core/transport/internet/browser_dialer"
 	"github.com/xtls/xray-core/transport/internet/stat"
 	"github.com/xtls/xray-core/transport/pipe"
 )
@@ -269,6 +270,9 @@ func DialSystem(ctx context.Context, dest net.Destination, sockopt *SocketConfig
 	}
 
 	if len(sockopt.DialerProxy) > 0 {
+		if browser_dialer.IsBrowserDialerProxy(sockopt.DialerProxy) {
+			return nil, errors.New("dialerProxy ", sockopt.DialerProxy, " only supports WebSocket or splithttp").AtError()
+		}
 		if obm == nil {
 			return nil, errors.New("there is no outbound manager for dialerProxy").AtError()
 		}

transport/internet/splithttp/browser_client.go

@@ -15,6 +15,7 @@ import (
 // BrowserDialerClient implements splithttp.DialerClient in terms of browser dialer
 type BrowserDialerClient struct {
 	transportConfig *Config
+	browserDialer   string
 }
 
 func (c *BrowserDialerClient) IsClosed() bool {
@@ -33,7 +34,7 @@ func (c *BrowserDialerClient) OpenStream(ctx context.Context, url string, sessio
 
 	c.transportConfig.FillStreamRequest(request, sessionId, "")
 
-	conn, err := browser_dialer.DialGet(request.URL.String(), request.Header, request.Cookies())
+	conn, err := browser_dialer.DialGetWithAddress(c.browserDialer, request.URL.String(), request.Header, request.Cookies())
 	dummyAddr := &net.IPAddr{}
 	if err != nil {
 		return nil, dummyAddr, dummyAddr, err
@@ -62,7 +63,7 @@ func (c *BrowserDialerClient) PostPacket(ctx context.Context, url string, sessio
 		}
 	}
 
-	err = browser_dialer.DialPacket(method, request.URL.String(), request.Header, request.Cookies(), bytes)
+	err = browser_dialer.DialPacketWithAddress(c.browserDialer, method, request.URL.String(), request.Header, request.Cookies(), bytes)
 	if err != nil {
 		return err
 	}

transport/internet/splithttp/dialer.go

@@ -40,6 +40,20 @@ type dialerConf struct {
 	*internet.MemoryStreamConfig
 }
 
+type errorDialerClient struct {
+	err error
+}
+
+func (c *errorDialerClient) IsClosed() bool { return true }
+
+func (c *errorDialerClient) OpenStream(context.Context, string, string, io.Reader, bool) (io.ReadCloser, net.Addr, net.Addr, error) {
+	return nil, nil, nil, c.err
+}
+
+func (c *errorDialerClient) PostPacket(context.Context, string, string, string, buf.MultiBuffer) error {
+	return c.err
+}
+
 var (
 	globalDialerMap    map[dialerConf]*XmuxManager
 	globalDialerAccess sync.Mutex
@@ -47,9 +61,24 @@ var (
 
 func getHTTPClient(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (DialerClient, *XmuxClient) {
 	realityConfig := reality.ConfigFromStreamSettings(streamSettings)
+	browserDialer := ""
+	if streamSettings.SocketSettings != nil {
+		if browser_dialer.IsBrowserDialerProxy(streamSettings.SocketSettings.DialerProxy) {
+			browserDialer = streamSettings.SocketSettings.DialerProxy
+		}
+	}
 
-	if browser_dialer.HasBrowserDialer() && realityConfig == nil {
-		return &BrowserDialerClient{transportConfig: streamSettings.ProtocolSettings.(*Config)}, nil
+	if browserDialer != "" && realityConfig == nil {
+		transportConfig := streamSettings.ProtocolSettings.(*Config)
+		if transportConfig.Mode != "auto" && transportConfig.Mode != "packet-up" {
+			return &errorDialerClient{
+				err: errors.New("browserDialer with splithttp only supports modes \"auto\" or \"packet-up\", got: \"", transportConfig.Mode, "\""),
+			}, nil
+		}
+		return &BrowserDialerClient{
+			transportConfig: transportConfig,
+			browserDialer:   browserDialer,
+		}, nil
 	}
 
 	globalDialerAccess.Lock()

transport/internet/websocket/dialer.go

@@ -117,8 +117,14 @@ func dialWebSocket(ctx context.Context, dest net.Destination, streamSettings *in
 	}
 	uri := protocol + "://" + host + wsSettings.GetNormalizedPath()
 
-	if browser_dialer.HasBrowserDialer() {
-		conn, err := browser_dialer.DialWS(uri, ed)
+	browserDialer := ""
+	if streamSettings.SocketSettings != nil {
+		if browser_dialer.IsBrowserDialerProxy(streamSettings.SocketSettings.DialerProxy) {
+			browserDialer = streamSettings.SocketSettings.DialerProxy
+		}
+	}
+	if browserDialer != "" {
+		conn, err := browser_dialer.DialWSWithAddress(browserDialer, uri, ed)
 		if err != nil {
 			return nil, err
 		}