XHTTP: Add "stream-up" mode for client & server (#3994)

infra/conf/transport_internet.go

@@ -233,6 +233,7 @@ type SplitHTTPConfig struct {
 	XPaddingBytes        *Int32Range       `json:"xPaddingBytes"`
 	Xmux                 Xmux              `json:"xmux"`
 	DownloadSettings     *StreamConfig     `json:"downloadSettings"`
+	Mode                 string            `json:"mode"`
 }
 
 type Xmux struct {
@@ -289,6 +290,14 @@ func (c *SplitHTTPConfig) Build() (proto.Message, error) {
 		muxProtobuf.CMaxReuseTimes.To = 128
 	}
 
+	switch c.Mode {
+	case "":
+		c.Mode = "auto"
+	case "auto", "packet-up", "stream-up":
+	default:
+		return nil, errors.New("unsupported mode: " + c.Mode)
+	}
+
 	config := &splithttp.Config{
 		Path:                 c.Path,
 		Host:                 c.Host,
@@ -299,6 +308,7 @@ func (c *SplitHTTPConfig) Build() (proto.Message, error) {
 		NoSSEHeader:          c.NoSSEHeader,
 		XPaddingBytes:        splithttpNewRandRangeConfig(c.XPaddingBytes),
 		Xmux:                 &muxProtobuf,
+		Mode:                 c.Mode,
 	}
 	var err error
 	if c.DownloadSettings != nil {

transport/internet/splithttp/browser_client.go

@@ -14,6 +14,10 @@ import (
 // has no fields because everything is global state :O)
 type BrowserDialerClient struct{}
 
+func (c *BrowserDialerClient) OpenUpload(ctx context.Context, baseURL string) io.WriteCloser {
+	panic("not implemented yet")
+}
+
 func (c *BrowserDialerClient) OpenDownload(ctx context.Context, baseURL string) (io.ReadCloser, gonet.Addr, gonet.Addr, error) {
 	conn, err := browser_dialer.DialGet(baseURL)
 	dummyAddr := &gonet.IPAddr{}

transport/internet/splithttp/client.go

@@ -25,6 +25,10 @@ type DialerClient interface {
 	// (ctx, baseURL) -> (downloadReader, remoteAddr, localAddr)
 	// baseURL already contains sessionId
 	OpenDownload(context.Context, string) (io.ReadCloser, net.Addr, net.Addr, error)
+
+	// (ctx, baseURL) -> uploadWriter
+	// baseURL already contains sessionId
+	OpenUpload(context.Context, string) io.WriteCloser
 }
 
 // implements splithttp.DialerClient in terms of direct network connections
@@ -38,6 +42,14 @@ type DefaultDialerClient struct {
 	dialUploadConn func(ctxInner context.Context) (net.Conn, error)
 }
 
+func (c *DefaultDialerClient) OpenUpload(ctx context.Context, baseURL string) io.WriteCloser {
+	reader, writer := io.Pipe()
+	req, _ := http.NewRequestWithContext(ctx, "POST", baseURL, reader)
+	req.Header = c.transportConfig.GetRequestHeader()
+	go c.client.Do(req)
+	return writer
+}
+
 func (c *DefaultDialerClient) OpenDownload(ctx context.Context, baseURL string) (io.ReadCloser, gonet.Addr, gonet.Addr, error) {
 	var remoteAddr gonet.Addr
 	var localAddr gonet.Addr

transport/internet/splithttp/config.pb.go

@@ -36,6 +36,7 @@ type Config struct {
 	XPaddingBytes        *RandRangeConfig       `protobuf:"bytes,8,opt,name=xPaddingBytes,proto3" json:"xPaddingBytes,omitempty"`
 	Xmux                 *Multiplexing          `protobuf:"bytes,9,opt,name=xmux,proto3" json:"xmux,omitempty"`
 	DownloadSettings     *internet.StreamConfig `protobuf:"bytes,10,opt,name=downloadSettings,proto3" json:"downloadSettings,omitempty"`
+	Mode                 string                 `protobuf:"bytes,11,opt,name=mode,proto3" json:"mode,omitempty"`
 }
 
 func (x *Config) Reset() {
@@ -138,6 +139,13 @@ func (x *Config) GetDownloadSettings() *internet.StreamConfig {
 	return nil
 }
 
+func (x *Config) GetMode() string {
+	if x != nil {
+		return x.Mode
+	}
+	return ""
+}
+
 type RandRangeConfig struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
@@ -270,7 +278,7 @@ var file_transport_internet_splithttp_config_proto_rawDesc = []byte{
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@@ -314,47 +322,48 @@ var file_transport_internet_splithttp_config_proto_rawDesc = []byte{
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 }
 
 var (

transport/internet/splithttp/config.proto

@@ -19,6 +19,7 @@ message Config {
   RandRangeConfig xPaddingBytes = 8;
   Multiplexing xmux = 9;
   xray.transport.internet.StreamConfig downloadSettings = 10;
+  string mode = 11;
 }
 
 message RandRangeConfig {

transport/internet/splithttp/dialer.go

@@ -254,9 +254,9 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 
 	httpClient, muxRes := getHTTPClient(ctx, dest, streamSettings)
 
-	var httpClient2 DialerClient
+	httpClient2 := httpClient
+	requestURL2 := requestURL
 	var muxRes2 *muxResource
-	var requestURL2 url.URL
 	if transportConfiguration.DownloadSettings != nil {
 		globalDialerAccess.Lock()
 		if streamSettings.DownloadSettings == nil {
@@ -279,11 +279,10 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 		requestURL2.RawQuery = config2.GetNormalizedQuery()
 	}
 
-	maxUploadSize := scMaxEachPostBytes.roll()
+	reader, remoteAddr, localAddr, err := httpClient2.OpenDownload(context.WithoutCancel(ctx), requestURL2.String())
-	// WithSizeLimit(0) will still allow single bytes to pass, and a lot of
+	if err != nil {
-	// code relies on this behavior. Subtract 1 so that together with
+		return nil, err
-	// uploadWriter wrapper, exact size limits can be enforced
+	}
-	uploadPipeReader, uploadPipeWriter := pipe.New(pipe.WithSizeLimit(maxUploadSize - 1))
 
 	if muxRes != nil {
 		muxRes.OpenRequests.Add(1)
@@ -291,15 +290,48 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 	if muxRes2 != nil {
 		muxRes2.OpenRequests.Add(1)
 	}
+	closed := false
 
-	go func() {
+	conn := splitConn{
+		writer:     nil,
+		reader:     reader,
+		remoteAddr: remoteAddr,
+		localAddr:  localAddr,
+		onClose: func() {
+			if closed {
+				return
+			}
+			closed = true
 			if muxRes != nil {
-			defer muxRes.OpenRequests.Add(-1)
+				muxRes.OpenRequests.Add(-1)
 			}
 			if muxRes2 != nil {
-			defer muxRes2.OpenRequests.Add(-1)
+				muxRes2.OpenRequests.Add(-1)
+			}
+		},
 	}
 
+	mode := transportConfiguration.Mode
+	if mode == "auto" && realityConfig != nil {
+		mode = "stream-up"
+	}
+	if mode == "stream-up" {
+		conn.writer = httpClient.OpenUpload(ctx, requestURL.String())
+		return stat.Connection(&conn), nil
+	}
+
+	maxUploadSize := scMaxEachPostBytes.roll()
+	// WithSizeLimit(0) will still allow single bytes to pass, and a lot of
+	// code relies on this behavior. Subtract 1 so that together with
+	// uploadWriter wrapper, exact size limits can be enforced
+	uploadPipeReader, uploadPipeWriter := pipe.New(pipe.WithSizeLimit(maxUploadSize - 1))
+
+	conn.writer = uploadWriter{
+		uploadPipeWriter,
+		maxUploadSize,
+	}
+
+	go func() {
 		requestsLimiter := semaphore.New(int(scMaxConcurrentPosts.roll()))
 		var requestCounter int64
 
@@ -352,30 +384,6 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 		}
 	}()
 
-	httpClient3 := httpClient
-	requestURL3 := requestURL
-	if httpClient2 != nil {
-		httpClient3 = httpClient2
-		requestURL3 = requestURL2
-	}
-
-	reader, remoteAddr, localAddr, err := httpClient3.OpenDownload(context.WithoutCancel(ctx), requestURL3.String())
-	if err != nil {
-		return nil, err
-	}
-
-	writer := uploadWriter{
-		uploadPipeWriter,
-		maxUploadSize,
-	}
-
-	conn := splitConn{
-		writer:     writer,
-		reader:     reader,
-		remoteAddr: remoteAddr,
-		localAddr:  localAddr,
-	}
-
 	return stat.Connection(&conn), nil
 }
 

transport/internet/splithttp/hub.go

@@ -100,6 +100,8 @@ func (h *requestHandler) ServeHTTP(writer http.ResponseWriter, request *http.Req
 		return
 	}
 
+	h.config.WriteResponseHeader(writer)
+
 	sessionId := ""
 	subpath := strings.Split(request.URL.Path[len(h.path):], "/")
 	if len(subpath) > 0 {
@@ -134,7 +136,26 @@ func (h *requestHandler) ServeHTTP(writer http.ResponseWriter, request *http.Req
 		}
 
 		if seq == "" {
-			errors.LogInfo(context.Background(), "no seq on request:", request.URL.Path)
+			if h.config.Mode == "packet-up" {
+				errors.LogInfo(context.Background(), "stream-up mode is not allowed")
+				writer.WriteHeader(http.StatusBadRequest)
+				return
+			}
+			err = currentSession.uploadQueue.Push(Packet{
+				Reader: request.Body,
+			})
+			if err != nil {
+				errors.LogInfoInner(context.Background(), err, "failed to upload (PushReader)")
+				writer.WriteHeader(http.StatusConflict)
+			} else {
+				writer.WriteHeader(http.StatusOK)
+				<-request.Context().Done()
+			}
+			return
+		}
+
+		if h.config.Mode == "stream-up" {
+			errors.LogInfo(context.Background(), "packet-up mode is not allowed")
 			writer.WriteHeader(http.StatusBadRequest)
 			return
 		}
@@ -148,14 +169,14 @@ func (h *requestHandler) ServeHTTP(writer http.ResponseWriter, request *http.Req
 		}
 
 		if err != nil {
-			errors.LogInfoInner(context.Background(), err, "failed to upload")
+			errors.LogInfoInner(context.Background(), err, "failed to upload (ReadAll)")
 			writer.WriteHeader(http.StatusInternalServerError)
 			return
 		}
 
 		seqInt, err := strconv.ParseUint(seq, 10, 64)
 		if err != nil {
-			errors.LogInfoInner(context.Background(), err, "failed to upload")
+			errors.LogInfoInner(context.Background(), err, "failed to upload (ParseUint)")
 			writer.WriteHeader(http.StatusInternalServerError)
 			return
 		}
@@ -166,12 +187,11 @@ func (h *requestHandler) ServeHTTP(writer http.ResponseWriter, request *http.Req
 		})
 
 		if err != nil {
-			errors.LogInfoInner(context.Background(), err, "failed to upload")
+			errors.LogInfoInner(context.Background(), err, "failed to upload (PushPayload)")
 			writer.WriteHeader(http.StatusInternalServerError)
 			return
 		}
 
-		h.config.WriteResponseHeader(writer)
 		writer.WriteHeader(http.StatusOK)
 	} else if request.Method == "GET" {
 		responseFlusher, ok := writer.(http.Flusher)
@@ -195,8 +215,6 @@ func (h *requestHandler) ServeHTTP(writer http.ResponseWriter, request *http.Req
 			writer.Header().Set("Content-Type", "text/event-stream")
 		}
 
-		h.config.WriteResponseHeader(writer)
-
 		writer.WriteHeader(http.StatusOK)
 
 		responseFlusher.Flush()
@@ -223,6 +241,7 @@ func (h *requestHandler) ServeHTTP(writer http.ResponseWriter, request *http.Req
 
 		conn.Close()
 	} else {
+		errors.LogInfo(context.Background(), "unsupported method: ", request.Method)
 		writer.WriteHeader(http.StatusMethodNotAllowed)
 	}
 }

transport/internet/splithttp/upload_queue.go

@@ -6,17 +6,20 @@ package splithttp
 import (
 	"container/heap"
 	"io"
+	"runtime"
 	"sync"
 
 	"github.com/xtls/xray-core/common/errors"
 )
 
 type Packet struct {
+	Reader  io.ReadCloser
 	Payload []byte
 	Seq     uint64
 }
 
 type uploadQueue struct {
+	reader          io.ReadCloser
 	pushedPackets   chan Packet
 	writeCloseMutex sync.Mutex
 	heap            uploadHeap
@@ -39,7 +42,16 @@ func (h *uploadQueue) Push(p Packet) error {
 	h.writeCloseMutex.Lock()
 	defer h.writeCloseMutex.Unlock()
 
+	runtime.Gosched()
+	if h.reader != nil && p.Reader != nil {
+		p.Reader.Close()
+		return errors.New("h.reader already exists")
+	}
+
 	if h.closed {
+		if p.Reader != nil {
+			p.Reader.Close()
+		}
 		return errors.New("splithttp packet queue closed")
 	}
 
@@ -55,10 +67,18 @@ func (h *uploadQueue) Close() error {
 		h.closed = true
 		close(h.pushedPackets)
 	}
+	runtime.Gosched()
+	if h.reader != nil {
+		return h.reader.Close()
+	}
 	return nil
 }
 
 func (h *uploadQueue) Read(b []byte) (int, error) {
+	if h.reader != nil {
+		return h.reader.Read(b)
+	}
+
 	if h.closed {
 		return 0, io.EOF
 	}
@@ -68,6 +88,10 @@ func (h *uploadQueue) Read(b []byte) (int, error) {
 		if !more {
 			return 0, io.EOF
 		}
+		if packet.Reader != nil {
+			h.reader = packet.Reader
+			return h.reader.Read(b)
+		}
 		heap.Push(&h.heap, packet)
 	}