XDRIVE transport: Add the Google Drive and "template" backend (#6748)

https://github.com/XTLS/Xray-core/pull/5645#issuecomment-3849778103
https://github.com/XTLS/Xray-core/pull/5645#issuecomment-3851839033
https://github.com/XTLS/Xray-core/pull/6745#issuecomment-5627294204
https://github.com/XTLS/Xray-core/pull/6748#issuecomment-5660444946
https://github.com/XTLS/Xray-core/pull/6748#issuecomment-5719209642

---------

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

common/buf/readv_windows.go

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

infra/conf/transport_internet.go

@@ -36,6 +36,8 @@ func (p TransportProtocol) Build() (string, error) {
 		return "", errors.PrintRemovedFeatureError("QUIC transport (without web service, etc.)", "XHTTP stream-one H3")
 	case "hysteria":
 		return "hysteria", nil
+	case "xdrive":
+		return "xdrive", nil
 	default:
 		return "", errors.New("Config: unknown transport protocol: ", p)
 	}
@@ -59,6 +61,7 @@ type StreamConfig struct {
 	WSSettings          *WebSocketConfig   `json:"wsSettings"`
 	HTTPUPGRADESettings *HttpUpgradeConfig `json:"httpupgradeSettings"`
 	HysteriaSettings    *HysteriaConfig    `json:"hysteriaSettings"`
+	XDRIVESettings      *XDriveConfig      `json:"xdriveSettings"`
 	SocketSettings      *SocketConfig      `json:"sockopt"`
 }
 
@@ -192,6 +195,16 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 			Settings:     serial.ToTypedMessage(hs),
 		})
 	}
+	if c.XDRIVESettings != nil {
+		xs, err := c.XDRIVESettings.Build()
+		if err != nil {
+			return nil, errors.New("Failed to build XDRIVE config.").Base(err)
+		}
+		config.TransportSettings = append(config.TransportSettings, &internet.TransportConfig{
+			ProtocolName: "xdrive",
+			Settings:     serial.ToTypedMessage(xs),
+		})
+	}
 	if c.SocketSettings != nil {
 		ss, err := c.SocketSettings.Build()
 		if err != nil {

infra/conf/transport_method.go

@@ -23,6 +23,7 @@ import (
 	"github.com/xtls/xray-core/transport/internet/splithttp"
 	"github.com/xtls/xray-core/transport/internet/tcp"
 	"github.com/xtls/xray-core/transport/internet/websocket"
+	"github.com/xtls/xray-core/transport/internet/xdrive"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -794,3 +795,50 @@ func readFileOrString(f string, s []string) ([]byte, error) {
 	}
 	return nil, errors.New("both file and bytes are empty.")
 }
+
+type XDriveConfig struct {
+	RemoteFolder      string          `json:"remoteFolder"`
+	Service           string          `json:"service"`
+	Secrets           []string        `json:"secrets"`
+	SegmentBytes      uint32          `json:"segmentBytes"`
+	FlushIntervalMs   uint32          `json:"flushIntervalMs"`
+	PollIntervalMs    uint32          `json:"pollIntervalMs"`
+	MaxPollIntervalMs uint32          `json:"maxPollIntervalMs"`
+	SessionTTLSeconds uint32          `json:"sessionTtlSeconds"`
+	Concurrency       uint32          `json:"concurrency"`
+	EagerWindowMs     uint32          `json:"eagerWindowMs"`
+	HoleTimeoutMs     uint32          `json:"holeTimeoutMs"`
+	Template          json.RawMessage `json:"template"`
+}
+
+// Build implements Buildable.
+func (c *XDriveConfig) Build() (proto.Message, error) {
+	switch c.Service {
+	case "local":
+	case "Google Drive":
+		if len(c.Secrets) != 3 {
+			return nil, errors.New("Google Drive needs 3 secrets in order of ClientID, ClientSecret, RefreshToken")
+		}
+	case "template":
+		if len(c.Template) == 0 {
+			return nil, errors.New(`service "template" needs a "template" object`)
+		}
+	default:
+		return nil, errors.New("unsupported service")
+	}
+	config := &xdrive.Config{
+		RemoteFolder:      c.RemoteFolder,
+		Service:           c.Service,
+		Secrets:           c.Secrets,
+		SegmentBytes:      c.SegmentBytes,
+		FlushIntervalMs:   c.FlushIntervalMs,
+		PollIntervalMs:    c.PollIntervalMs,
+		MaxPollIntervalMs: c.MaxPollIntervalMs,
+		SessionTtlSeconds: c.SessionTTLSeconds,
+		Concurrency:       c.Concurrency,
+		EagerWindowMs:     c.EagerWindowMs,
+		HoleTimeoutMs:     c.HoleTimeoutMs,
+		Template:          string(c.Template),
+	}
+	return config, nil
+}

infra/conf/transport_test.go

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

main/distro/all/all.go

@@ -60,6 +60,7 @@ import (
 	_ "github.com/xtls/xray-core/transport/internet/tls"
 	_ "github.com/xtls/xray-core/transport/internet/udp"
 	_ "github.com/xtls/xray-core/transport/internet/websocket"
+	_ "github.com/xtls/xray-core/transport/internet/xdrive"
 
 	// Transport headers
 	_ "github.com/xtls/xray-core/transport/internet/headers/http"

proxy/tun/handler.go

@@ -37,6 +37,25 @@ type Handler struct {
 	downlinkCounter stats.Counter
 }
 
+type tunUDPStatsWriter struct {
+	writer  buf.Writer
+	counter stats.Counter
+}
+
+func (w *tunUDPStatsWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
+	for len(mb) > 0 {
+		remaining, packet := buf.SplitFirst(mb)
+		packetSize := packet.Len()
+		if err := w.writer.WriteMultiBuffer(buf.MultiBuffer{packet}); err != nil {
+			buf.ReleaseMulti(remaining)
+			return err
+		}
+		w.counter.Add(int64(packetSize))
+		mb = remaining
+	}
+	return nil
+}
+
 // ConnectionHandler interface with the only method that stack is going to push new connections to
 type ConnectionHandler interface {
 	HandleConnection(conn net.Conn, destination net.Destination)
@@ -171,7 +190,8 @@ func (t *Handler) HandleConnection(conn net.Conn, destination net.Destination) {
 		return
 	}
 	source := net.DestinationFromAddr(remote)
-	if t.uplinkCounter != nil || t.downlinkCounter != nil {
+	isUDP := destination.Network == net.Network_UDP
+	if !isUDP && (t.uplinkCounter != nil || t.downlinkCounter != nil) {
 		conn = &stat.CounterConnection{
 			Connection:   conn,
 			ReadCounter:  t.uplinkCounter,
@@ -203,9 +223,18 @@ func (t *Handler) HandleConnection(conn net.Conn, destination net.Destination) {
 	})
 	errors.LogInfo(ctx, "processing from ", source, " to ", destination)
 
+	reader := &buf.TimeoutWrapperReader{Reader: buf.NewReader(conn)}
+	writer := buf.NewWriter(conn)
+	if isUDP {
+		reader.Counter = t.uplinkCounter
+		if t.downlinkCounter != nil {
+			writer = &tunUDPStatsWriter{writer: writer, counter: t.downlinkCounter}
+		}
+	}
+
 	link := &transport.Link{
-		Reader: &buf.TimeoutWrapperReader{Reader: buf.NewReader(conn)},
-		Writer: buf.NewWriter(conn),
+		Reader: reader,
+		Writer: writer,
 	}
 	if err := t.dispatcher.DispatchLink(ctx, destination, link); err != nil {
 		errors.LogError(ctx, errors.New("connection closed").Base(err))

transport/internet/xdrive/client.go

@@ -0,0 +1,156 @@
+package xdrive
+
+import (
+	"context"
+	gotls "crypto/tls"
+	"net/http"
+	"time"
+
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/reality"
+	"github.com/xtls/xray-core/transport/internet/tls"
+	"golang.org/x/net/http2"
+)
+
+type serviceTransport struct {
+	plain  http.RoundTripper
+	secure http.RoundTripper
+}
+
+func (t *serviceTransport) RoundTrip(r *http.Request) (*http.Response, error) {
+	if r.URL.Scheme == "https" {
+		return t.secure.RoundTrip(r)
+	}
+	return t.plain.RoundTrip(r)
+}
+
+func newServiceClient(streamSettings *internet.MemoryStreamConfig, timeout time.Duration, maxConns int) *http.Client {
+	var (
+		tlsConfig     *tls.Config
+		realityConfig *reality.Config
+		sockopt       *internet.SocketConfig
+		fronting      *net.Destination
+	)
+	if streamSettings != nil {
+		tlsConfig = tls.ConfigFromStreamSettings(streamSettings)
+		realityConfig = reality.ConfigFromStreamSettings(streamSettings)
+		sockopt = streamSettings.SocketSettings
+		fronting = streamSettings.Destination
+	}
+	overHTTP2 := allowsHTTP2(tlsConfig, realityConfig)
+
+	dial := func(ctx context.Context, addr string) (net.Conn, net.Destination, error) {
+		host, err := net.ParseDestination("tcp:" + addr)
+		if err != nil {
+			return nil, host, errors.New("bad address: ", addr).Base(err)
+		}
+
+		target := host
+		if fronting != nil {
+			target.Address = fronting.Address
+			if fronting.Port != 0 {
+				target.Port = fronting.Port
+			}
+		}
+
+		conn, err := internet.DialSystem(ctx, target, sockopt)
+		if err != nil {
+			return nil, host, err
+		}
+		if streamSettings != nil && streamSettings.TcpmaskManager != nil {
+			masked, err := streamSettings.TcpmaskManager.WrapConnClient(conn)
+			if err != nil {
+				conn.Close()
+				return nil, host, errors.New("mask err").Base(err)
+			}
+			conn = masked
+		}
+		return conn, host, nil
+	}
+
+	dialPlain := func(ctx context.Context, network, addr string) (net.Conn, error) {
+		conn, _, err := dial(ctx, addr)
+		return conn, err
+	}
+
+	dialTLS := func(ctx context.Context, addr string) (net.Conn, error) {
+		conn, host, err := dial(ctx, addr)
+		if err != nil {
+			return nil, err
+		}
+
+		if realityConfig != nil {
+			return reality.UClient(conn, realityConfig, ctx, host)
+		}
+
+		gotlsConfig := &gotls.Config{ServerName: host.Address.String()}
+		if tlsConfig != nil {
+			gotlsConfig = tlsConfig.GetTLSConfig(tls.WithDestination(host))
+		}
+		if len(gotlsConfig.NextProtos) != 1 {
+			if overHTTP2 {
+				gotlsConfig.NextProtos = []string{"h2"}
+			} else {
+				gotlsConfig.NextProtos = []string{"http/1.1"}
+			}
+		}
+
+		if tlsConfig != nil {
+			if fingerprint := tls.GetFingerprint(tlsConfig.Fingerprint); fingerprint != nil {
+				uconn := tls.UClient(conn, gotlsConfig, fingerprint)
+				if err := uconn.(*tls.UConn).HandshakeContext(ctx); err != nil {
+					conn.Close()
+					return nil, err
+				}
+				return uconn, nil
+			}
+		}
+		return tls.Client(conn, gotlsConfig), nil
+	}
+
+	var secure http.RoundTripper
+	if overHTTP2 {
+		secure = &http2.Transport{
+			DialTLSContext: func(ctx context.Context, network, addr string, cfg *gotls.Config) (net.Conn, error) {
+				return dialTLS(ctx, addr)
+			},
+			IdleConnTimeout: net.ConnIdleTimeout,
+		}
+	} else {
+		secure = &http.Transport{
+			DialTLSContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return dialTLS(ctx, addr)
+			},
+			IdleConnTimeout:     net.ConnIdleTimeout,
+			MaxIdleConns:        maxConns,
+			MaxIdleConnsPerHost: maxConns,
+			MaxConnsPerHost:     maxConns,
+		}
+	}
+
+	return &http.Client{
+		Transport: &serviceTransport{
+			plain: &http.Transport{
+				DialContext:         dialPlain,
+				IdleConnTimeout:     net.ConnIdleTimeout,
+				MaxIdleConns:        maxConns,
+				MaxIdleConnsPerHost: maxConns,
+				MaxConnsPerHost:     maxConns,
+			},
+			secure: secure,
+		},
+		Timeout: timeout,
+	}
+}
+
+func allowsHTTP2(tlsConfig *tls.Config, realityConfig *reality.Config) bool {
+	if realityConfig != nil {
+		return true
+	}
+	if tlsConfig == nil {
+		return false
+	}
+	return len(tlsConfig.NextProtocol) == 1 && tlsConfig.NextProtocol[0] == "h2"
+}

transport/internet/xdrive/client_test.go

@@ -0,0 +1,101 @@
+package xdrive
+
+import (
+	"context"
+	gotls "crypto/tls"
+	"net"
+	"net/http"
+	"sync"
+	"testing"
+	"time"
+
+	xnet "github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/tls"
+)
+
+func recordingTLSListener(t *testing.T, sni *string, mu *sync.Mutex) net.Listener {
+	t.Helper()
+
+	ln, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("listen: %v", err)
+	}
+	go func() {
+		for {
+			conn, err := ln.Accept()
+			if err != nil {
+				return
+			}
+			cfg := &gotls.Config{
+				GetConfigForClient: func(hello *gotls.ClientHelloInfo) (*gotls.Config, error) {
+					mu.Lock()
+					*sni = hello.ServerName
+					mu.Unlock()
+					return nil, nil
+				},
+			}
+			tconn := gotls.Server(conn, cfg)
+			tconn.HandshakeContext(context.Background())
+			tconn.Close()
+		}
+	}()
+	t.Cleanup(func() { ln.Close() })
+	return ln
+}
+
+func sniForSettings(t *testing.T, serverName string) string {
+	t.Helper()
+
+	var (
+		sni string
+		mu  sync.Mutex
+	)
+	ln := recordingTLSListener(t, &sni, &mu)
+	addr := ln.Addr().(*net.TCPAddr)
+
+	settings := &internet.MemoryStreamConfig{
+		ProtocolName: protocolName,
+		Destination: &xnet.Destination{
+			Address: xnet.ParseAddress(addr.IP.String()),
+			Port:    xnet.Port(addr.Port),
+			Network: xnet.Network_TCP,
+		},
+		SecuritySettings: &tls.Config{ServerName: serverName},
+	}
+
+	prev := driveFilesURL
+	driveFilesURL = "https://www.googleapis.com/drive/v3/files"
+	defer func() { driveFilesURL = prev }()
+
+	client := newServiceClient(settings, 5*time.Second, 8)
+	req, err := http.NewRequest(http.MethodGet, driveFilesURL, nil)
+	if err != nil {
+		t.Fatalf("request: %v", err)
+	}
+	client.Do(req)
+
+	deadline := time.Now().Add(3 * time.Second)
+	for time.Now().Before(deadline) {
+		mu.Lock()
+		got := sni
+		mu.Unlock()
+		if got != "" {
+			return got
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
+	return ""
+}
+
+func TestServiceSNIDefaultsToHost(t *testing.T) {
+	if got := sniForSettings(t, ""); got != "www.googleapis.com" {
+		t.Fatalf("SNI defaulted to %q, want the host www.googleapis.com, not address", got)
+	}
+}
+
+func TestServiceSNIOverride(t *testing.T) {
+	if got := sniForSettings(t, "www.google.com"); got != "www.google.com" {
+		t.Fatalf("explicit serverName gave SNI %q, want www.google.com", got)
+	}
+}

transport/internet/xdrive/config.pb.go

@@ -0,0 +1,222 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.36.11
+// 	protoc        v6.33.5
+// source: transport/internet/xdrive/config.proto
+
+package xdrive
+
+import (
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+	unsafe "unsafe"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+type Config struct {
+	state             protoimpl.MessageState `protogen:"open.v1"`
+	RemoteFolder      string                 `protobuf:"bytes,1,opt,name=remote_folder,json=remoteFolder,proto3" json:"remote_folder,omitempty"`
+	Service           string                 `protobuf:"bytes,2,opt,name=service,proto3" json:"service,omitempty"`
+	Secrets           []string               `protobuf:"bytes,3,rep,name=secrets,proto3" json:"secrets,omitempty"`
+	SegmentBytes      uint32                 `protobuf:"varint,4,opt,name=segment_bytes,json=segmentBytes,proto3" json:"segment_bytes,omitempty"`
+	FlushIntervalMs   uint32                 `protobuf:"varint,5,opt,name=flush_interval_ms,json=flushIntervalMs,proto3" json:"flush_interval_ms,omitempty"`
+	PollIntervalMs    uint32                 `protobuf:"varint,6,opt,name=poll_interval_ms,json=pollIntervalMs,proto3" json:"poll_interval_ms,omitempty"`
+	MaxPollIntervalMs uint32                 `protobuf:"varint,7,opt,name=max_poll_interval_ms,json=maxPollIntervalMs,proto3" json:"max_poll_interval_ms,omitempty"`
+	SessionTtlSeconds uint32                 `protobuf:"varint,8,opt,name=session_ttl_seconds,json=sessionTtlSeconds,proto3" json:"session_ttl_seconds,omitempty"`
+	Concurrency       uint32                 `protobuf:"varint,9,opt,name=concurrency,proto3" json:"concurrency,omitempty"`
+	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"`
+	unknownFields     protoimpl.UnknownFields
+	sizeCache         protoimpl.SizeCache
+}
+
+func (x *Config) Reset() {
+	*x = Config{}
+	mi := &file_transport_internet_xdrive_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_xdrive_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_xdrive_config_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *Config) GetRemoteFolder() string {
+	if x != nil {
+		return x.RemoteFolder
+	}
+	return ""
+}
+
+func (x *Config) GetService() string {
+	if x != nil {
+		return x.Service
+	}
+	return ""
+}
+
+func (x *Config) GetSecrets() []string {
+	if x != nil {
+		return x.Secrets
+	}
+	return nil
+}
+
+func (x *Config) GetSegmentBytes() uint32 {
+	if x != nil {
+		return x.SegmentBytes
+	}
+	return 0
+}
+
+func (x *Config) GetFlushIntervalMs() uint32 {
+	if x != nil {
+		return x.FlushIntervalMs
+	}
+	return 0
+}
+
+func (x *Config) GetPollIntervalMs() uint32 {
+	if x != nil {
+		return x.PollIntervalMs
+	}
+	return 0
+}
+
+func (x *Config) GetMaxPollIntervalMs() uint32 {
+	if x != nil {
+		return x.MaxPollIntervalMs
+	}
+	return 0
+}
+
+func (x *Config) GetSessionTtlSeconds() uint32 {
+	if x != nil {
+		return x.SessionTtlSeconds
+	}
+	return 0
+}
+
+func (x *Config) GetConcurrency() uint32 {
+	if x != nil {
+		return x.Concurrency
+	}
+	return 0
+}
+
+func (x *Config) GetEagerWindowMs() uint32 {
+	if x != nil {
+		return x.EagerWindowMs
+	}
+	return 0
+}
+
+func (x *Config) GetHoleTimeoutMs() uint32 {
+	if x != nil {
+		return x.HoleTimeoutMs
+	}
+	return 0
+}
+
+func (x *Config) GetTemplate() string {
+	if x != nil {
+		return x.Template
+	}
+	return ""
+}
+
+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" +
+	"\x06Config\x12#\n" +
+	"\rremote_folder\x18\x01 \x01(\tR\fremoteFolder\x12\x18\n" +
+	"\aservice\x18\x02 \x01(\tR\aservice\x12\x18\n" +
+	"\asecrets\x18\x03 \x03(\tR\asecrets\x12#\n" +
+	"\rsegment_bytes\x18\x04 \x01(\rR\fsegmentBytes\x12*\n" +
+	"\x11flush_interval_ms\x18\x05 \x01(\rR\x0fflushIntervalMs\x12(\n" +
+	"\x10poll_interval_ms\x18\x06 \x01(\rR\x0epollIntervalMs\x12/\n" +
+	"\x14max_poll_interval_ms\x18\a \x01(\rR\x11maxPollIntervalMs\x12.\n" +
+	"\x13session_ttl_seconds\x18\b \x01(\rR\x11sessionTtlSeconds\x12 \n" +
+	"\vconcurrency\x18\t \x01(\rR\vconcurrency\x12&\n" +
+	"\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"
+
+var (
+	file_transport_internet_xdrive_config_proto_rawDescOnce sync.Once
+	file_transport_internet_xdrive_config_proto_rawDescData []byte
+)
+
+func file_transport_internet_xdrive_config_proto_rawDescGZIP() []byte {
+	file_transport_internet_xdrive_config_proto_rawDescOnce.Do(func() {
+		file_transport_internet_xdrive_config_proto_rawDescData = protoimpl.X.CompressGZIP(unsafe.Slice(unsafe.StringData(file_transport_internet_xdrive_config_proto_rawDesc), len(file_transport_internet_xdrive_config_proto_rawDesc)))
+	})
+	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_goTypes = []any{
+	(*Config)(nil), // 0: xray.transport.internet.xdrive.Config
+}
+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
+}
+
+func init() { file_transport_internet_xdrive_config_proto_init() }
+func file_transport_internet_xdrive_config_proto_init() {
+	if File_transport_internet_xdrive_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_xdrive_config_proto_rawDesc), len(file_transport_internet_xdrive_config_proto_rawDesc)),
+			NumEnums:      0,
+			NumMessages:   1,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_transport_internet_xdrive_config_proto_goTypes,
+		DependencyIndexes: file_transport_internet_xdrive_config_proto_depIdxs,
+		MessageInfos:      file_transport_internet_xdrive_config_proto_msgTypes,
+	}.Build()
+	File_transport_internet_xdrive_config_proto = out.File
+	file_transport_internet_xdrive_config_proto_goTypes = nil
+	file_transport_internet_xdrive_config_proto_depIdxs = nil
+}

transport/internet/xdrive/config.proto

@@ -0,0 +1,19 @@
+syntax = "proto3";
+
+package xray.transport.internet.xdrive;
+option go_package = "github.com/xtls/xray-core/transport/internet/xdrive";
+
+message Config {
+  string remote_folder = 1;
+  string service = 2;
+  repeated string secrets = 3;
+  uint32 segment_bytes = 4;
+  uint32 flush_interval_ms = 5;
+  uint32 poll_interval_ms = 6;
+  uint32 max_poll_interval_ms = 7;
+  uint32 session_ttl_seconds = 8;
+  uint32 concurrency = 9;
+  uint32 eager_window_ms = 10;
+  uint32 hole_timeout_ms = 11;
+  string template = 12;
+}

transport/internet/xdrive/conn.go

@@ -0,0 +1,139 @@
+package xdrive
+
+import (
+	"context"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/xtls/xray-core/common/net"
+)
+
+var placeholderAddr = &net.TCPAddr{IP: net.IP{127, 0, 0, 1}, Port: 0}
+
+type Conn struct {
+	cancel  context.CancelFunc
+	writer  *walWriter
+	reader  *walReader
+	onClose func()
+
+	readBuf []byte
+
+	deadlineMu    sync.Mutex
+	readDeadline  time.Time
+	writeDeadline time.Time
+
+	closeOnce sync.Once
+	closeErr  error
+}
+
+func newConn(ctx context.Context, storage Storage, writePrefix, readPrefix string, p params, onClose func()) *Conn {
+	ctx, cancel := context.WithCancel(ctx)
+	return &Conn{
+		cancel:  cancel,
+		writer:  newWALWriter(ctx, storage, writePrefix, p),
+		reader:  newWALReader(ctx, storage, readPrefix, p),
+		onClose: onClose,
+	}
+}
+
+func (c *Conn) Read(b []byte) (int, error) {
+	if len(c.readBuf) == 0 {
+		data, err := c.receive()
+		if err != nil {
+			return 0, err
+		}
+		c.readBuf = data
+	}
+	n := copy(b, c.readBuf)
+	c.readBuf = c.readBuf[n:]
+	return n, nil
+}
+
+func (c *Conn) receive() ([]byte, error) {
+	deadline := c.getDeadline(true)
+	if deadline.IsZero() {
+		data, ok := <-c.reader.ch
+		if !ok {
+			return nil, c.reader.Err()
+		}
+		return data, nil
+	}
+
+	if !time.Now().Before(deadline) {
+		return nil, os.ErrDeadlineExceeded
+	}
+	timer := time.NewTimer(time.Until(deadline))
+	defer timer.Stop()
+
+	select {
+	case data, ok := <-c.reader.ch:
+		if !ok {
+			return nil, c.reader.Err()
+		}
+		return data, nil
+	case <-timer.C:
+		return nil, os.ErrDeadlineExceeded
+	}
+}
+
+func (c *Conn) Write(b []byte) (int, error) {
+	if deadline := c.getDeadline(false); !deadline.IsZero() && !time.Now().Before(deadline) {
+		return 0, os.ErrDeadlineExceeded
+	}
+	n, err := c.writer.Write(b)
+	if err == nil {
+		c.reader.Wake()
+	}
+	return n, err
+}
+
+func (c *Conn) Close() error {
+	c.closeOnce.Do(func() {
+		c.closeErr = c.writer.Close()
+		c.cancel()
+		if c.onClose != nil {
+			c.onClose()
+		}
+	})
+	return c.closeErr
+}
+
+func (c *Conn) LocalAddr() net.Addr {
+	return placeholderAddr
+}
+
+func (c *Conn) RemoteAddr() net.Addr {
+	return placeholderAddr
+}
+
+func (c *Conn) getDeadline(read bool) time.Time {
+	c.deadlineMu.Lock()
+	defer c.deadlineMu.Unlock()
+	if read {
+		return c.readDeadline
+	}
+	return c.writeDeadline
+}
+
+func (c *Conn) SetDeadline(t time.Time) error {
+	c.deadlineMu.Lock()
+	defer c.deadlineMu.Unlock()
+	c.readDeadline = t
+	c.writeDeadline = t
+	return nil
+}
+
+func (c *Conn) SetReadDeadline(t time.Time) error {
+	c.deadlineMu.Lock()
+	defer c.deadlineMu.Unlock()
+	c.readDeadline = t
+	return nil
+}
+
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+	c.deadlineMu.Lock()
+	defer c.deadlineMu.Unlock()
+	c.writeDeadline = t
+	return nil
+}

transport/internet/xdrive/drive.go

@@ -0,0 +1,575 @@
+package xdrive
+
+import (
+	"bytes"
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/xtls/xray-core/common/dice"
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/transport/internet"
+)
+
+const (
+	flatSeparator = "~"
+
+	driveBoundary    = "xdrive-boundary"
+	drivePageSize    = 1000
+	driveMaxAttempts = 8
+	driveMaxInflight = 32
+	driveInlineLimit = 12000
+	driveTimeout     = 60 * time.Second
+)
+
+var (
+	driveMaxBackoff     = 8 * time.Second
+	driveTokenURL       = "https://oauth2.googleapis.com/token"
+	driveFilesURL       = "https://www.googleapis.com/drive/v3/files"
+	driveUploadURL      = "https://www.googleapis.com/upload/drive/v3/files?uploadType=multipart&fields=id,name"
+	driveInitialBackoff = 200 * time.Millisecond
+)
+
+type driveStorage struct {
+	folder       string
+	clientID     string
+	clientSecret string
+	refreshToken string
+	client       *http.Client
+	tokenURL     string
+	filesURL     string
+	uploadURL    string
+	backoff      time.Duration
+
+	tokenMu     sync.Mutex
+	token       string
+	tokenExpiry time.Time
+
+	inflight chan struct{}
+
+	idMu sync.Mutex
+	ids  map[string]string
+}
+
+func newDriveStorage(streamSettings *internet.MemoryStreamConfig, config *Config) (*driveStorage, error) {
+	if config.RemoteFolder == "" {
+		return nil, errors.New(`empty "remoteFolder", it must be a Google Drive folder id`)
+	}
+	if len(config.Secrets) != 3 {
+		return nil, errors.New("Google Drive needs 3 secrets in order of ClientID, ClientSecret, RefreshToken")
+	}
+	for i, secret := range config.Secrets {
+		if secret == "" {
+			return nil, errors.New("Google Drive secret ", i, " is empty")
+		}
+	}
+
+	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),
+	}, nil
+}
+
+func flatten(name string) string {
+	return strings.ReplaceAll(name, "/", flatSeparator)
+}
+
+func quoteDriveValue(value string) string {
+	return strings.NewReplacer(`\`, `\\`, `'`, `\'`).Replace(value)
+}
+
+func (s *driveStorage) accessToken(ctx context.Context) (string, error) {
+	s.tokenMu.Lock()
+	defer s.tokenMu.Unlock()
+
+	if s.token != "" && time.Now().Before(s.tokenExpiry) {
+		return s.token, nil
+	}
+
+	form := url.Values{
+		"client_id":     {s.clientID},
+		"client_secret": {s.clientSecret},
+		"refresh_token": {s.refreshToken},
+		"grant_type":    {"refresh_token"},
+	}
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, s.tokenURL, strings.NewReader(form.Encode()))
+	if err != nil {
+		return "", errors.New("failed to build the token request").Base(err)
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+
+	resp, err := s.client.Do(req)
+	if err != nil {
+		return "", errors.New("failed to refresh the access token").Base(err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(io.LimitReader(resp.Body, 1<<20))
+	if err != nil {
+		return "", errors.New("failed to read the token response").Base(err)
+	}
+	if resp.StatusCode != http.StatusOK {
+		return "", errors.New("the token endpoint answered ", resp.StatusCode, ": ", string(body))
+	}
+
+	var parsed struct {
+		AccessToken string `json:"access_token"`
+		ExpiresIn   int64  `json:"expires_in"`
+	}
+	if err := json.Unmarshal(body, &parsed); err != nil {
+		return "", errors.New("failed to parse the token response").Base(err)
+	}
+	if parsed.AccessToken == "" {
+		return "", errors.New("the token endpoint returned no access token")
+	}
+
+	lifetime := parsed.ExpiresIn
+	if lifetime > 60 {
+		lifetime -= 60
+	}
+	s.token = parsed.AccessToken
+	s.tokenExpiry = time.Now().Add(time.Duration(lifetime) * time.Second)
+	return s.token, nil
+}
+
+func jitter(backoff time.Duration) time.Duration {
+	half := backoff / 2
+	if half <= 0 {
+		return backoff
+	}
+	return half + time.Duration(dice.Roll(int(half)))
+}
+
+func rateLimited(payload []byte) bool {
+	var parsed struct {
+		Error struct {
+			Status string `json:"status"`
+			Errors []struct {
+				Reason string `json:"reason"`
+			} `json:"errors"`
+		} `json:"error"`
+	}
+	if json.Unmarshal(payload, &parsed) != nil {
+		return false
+	}
+	for _, item := range parsed.Error.Errors {
+		switch item.Reason {
+		case "rateLimitExceeded", "userRateLimitExceeded", "sharingRateLimitExceeded":
+			return true
+		}
+	}
+	return parsed.Error.Status == "RESOURCE_EXHAUSTED"
+}
+
+func retryableStatus(status int) bool {
+	switch status {
+	case http.StatusTooManyRequests, http.StatusInternalServerError,
+		http.StatusBadGateway, http.StatusServiceUnavailable, http.StatusGatewayTimeout:
+		return true
+	}
+	return false
+}
+
+func (s *driveStorage) do(ctx context.Context, method, target, contentType string, body []byte) (int, []byte, error) {
+	backoff := s.backoff
+	var lastErr error
+
+	for attempt := 0; attempt < driveMaxAttempts; attempt++ {
+		if attempt > 0 {
+			select {
+			case <-ctx.Done():
+				return 0, nil, ctx.Err()
+			case <-time.After(jitter(backoff)):
+			}
+			backoff *= 2
+			if backoff > driveMaxBackoff {
+				backoff = driveMaxBackoff
+			}
+		}
+
+		token, err := s.accessToken(ctx)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+
+		select {
+		case s.inflight <- struct{}{}:
+		case <-ctx.Done():
+			return 0, nil, ctx.Err()
+		}
+
+		var reader io.Reader
+		if body != nil {
+			reader = bytes.NewReader(body)
+		}
+		req, err := http.NewRequestWithContext(ctx, method, target, reader)
+		if err != nil {
+			return 0, nil, errors.New("failed to build a Drive request").Base(err)
+		}
+		req.Header.Set("Authorization", "Bearer "+token)
+		if contentType != "" {
+			req.Header.Set("Content-Type", contentType)
+		}
+
+		resp, err := s.client.Do(req)
+		<-s.inflight
+		if err != nil {
+			if ctx.Err() != nil {
+				return 0, nil, ctx.Err()
+			}
+			lastErr = errors.New("Drive request failed").Base(err)
+			errors.LogWarningInner(ctx, err, "retrying a failed Drive request, attempt ",
+				attempt+1, " of ", driveMaxAttempts)
+			continue
+		}
+		payload, err := io.ReadAll(resp.Body)
+		resp.Body.Close()
+		if err != nil {
+			if ctx.Err() != nil {
+				return 0, nil, ctx.Err()
+			}
+			lastErr = errors.New("failed to read the Drive response").Base(err)
+			continue
+		}
+
+		if resp.StatusCode == http.StatusUnauthorized {
+			s.invalidateToken()
+			lastErr = errors.New("Drive rejected the access token")
+			continue
+		}
+		if resp.StatusCode == http.StatusForbidden && rateLimited(payload) {
+			lastErr = errors.New("Drive is rate limiting: ", string(payload))
+			errors.LogWarning(ctx, "rate limited by Drive, attempt ",
+				attempt+1, " of ", driveMaxAttempts)
+			continue
+		}
+		if retryableStatus(resp.StatusCode) {
+			lastErr = errors.New("Drive answered ", resp.StatusCode, ": ", string(payload))
+			errors.LogWarning(ctx, "retrying after Drive answered ", resp.StatusCode,
+				", attempt ", attempt+1, " of ", driveMaxAttempts)
+			continue
+		}
+		return resp.StatusCode, payload, nil
+	}
+
+	return 0, nil, lastErr
+}
+
+func (s *driveStorage) invalidateToken() {
+	s.tokenMu.Lock()
+	s.token = ""
+	s.tokenMu.Unlock()
+}
+
+func (s *driveStorage) rememberID(name, id string) {
+	s.idMu.Lock()
+	s.ids[name] = id
+	s.idMu.Unlock()
+}
+
+func (s *driveStorage) forgetID(name string) {
+	s.idMu.Lock()
+	delete(s.ids, name)
+	s.idMu.Unlock()
+}
+
+func (s *driveStorage) cachedID(name string) (string, bool) {
+	s.idMu.Lock()
+	defer s.idMu.Unlock()
+	id, ok := s.ids[name]
+	return id, ok
+}
+
+type driveFile struct {
+	id          string
+	description string
+}
+
+func (s *driveStorage) query(ctx context.Context, condition string) (map[string]driveFile, error) {
+	found := make(map[string]driveFile)
+	pageToken := ""
+
+	for {
+		params := url.Values{
+			"q":                         {"'" + quoteDriveValue(s.folder) + "' in parents and trashed = false and " + condition},
+			"fields":                    {"nextPageToken,files(id,name,description)"},
+			"pageSize":                  {fmt.Sprint(drivePageSize)},
+			"supportsAllDrives":         {"true"},
+			"includeItemsFromAllDrives": {"true"},
+		}
+		if pageToken != "" {
+			params.Set("pageToken", pageToken)
+		}
+
+		status, payload, err := s.do(ctx, http.MethodGet, s.filesURL+"?"+params.Encode(), "", nil)
+		if err != nil {
+			return nil, err
+		}
+		if status != http.StatusOK {
+			return nil, errors.New("Drive listing answered ", status, ": ", string(payload))
+		}
+
+		var parsed struct {
+			NextPageToken string `json:"nextPageToken"`
+			Files         []struct {
+				ID          string `json:"id"`
+				Name        string `json:"name"`
+				Description string `json:"description"`
+			} `json:"files"`
+		}
+		if err := json.Unmarshal(payload, &parsed); err != nil {
+			return nil, errors.New("failed to parse the Drive listing").Base(err)
+		}
+
+		for _, file := range parsed.Files {
+			found[file.Name] = driveFile{id: file.ID, description: file.Description}
+			s.rememberID(file.Name, file.ID)
+		}
+
+		pageToken = parsed.NextPageToken
+		if pageToken == "" {
+			return found, nil
+		}
+	}
+}
+
+func (s *driveStorage) resolveID(ctx context.Context, flat string) (string, error) {
+	if id, ok := s.cachedID(flat); ok {
+		return id, nil
+	}
+	found, err := s.query(ctx, "name = '"+quoteDriveValue(flat)+"'")
+	if err != nil {
+		return "", err
+	}
+	if file, ok := found[flat]; ok {
+		return file.id, nil
+	}
+	return "", errNotFound
+}
+
+func (s *driveStorage) Put(ctx context.Context, name string, data []byte) error {
+	if len(data) <= driveInlineLimit {
+		return s.putInline(ctx, name, data)
+	}
+	return s.putMedia(ctx, name, data)
+}
+
+func (s *driveStorage) putInline(ctx context.Context, name string, data []byte) error {
+	flat := flatten(name)
+
+	body, err := json.Marshal(map[string]interface{}{
+		"name":        flat,
+		"parents":     []string{s.folder},
+		"description": base64.StdEncoding.EncodeToString(data),
+	})
+	if err != nil {
+		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
+	}
+	if status != http.StatusOK {
+		return errors.New("Drive rejected the inline upload of ", name,
+			" with ", status, ": ", string(payload))
+	}
+
+	var parsed struct {
+		ID string `json:"id"`
+	}
+	if err := json.Unmarshal(payload, &parsed); err != nil {
+		return errors.New("failed to parse the Drive upload response").Base(err)
+	}
+	if parsed.ID != "" {
+		s.rememberID(flat, parsed.ID)
+	}
+	return nil
+}
+
+func (s *driveStorage) putMedia(ctx context.Context, name string, data []byte) error {
+	flat := flatten(name)
+
+	metadata, err := json.Marshal(map[string]interface{}{
+		"name":    flat,
+		"parents": []string{s.folder},
+	})
+	if err != nil {
+		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())
+	if err != nil {
+		return err
+	}
+	if status != http.StatusOK {
+		return errors.New("Drive upload of ", name, " answered ", status, ": ", string(payload))
+	}
+
+	var parsed struct {
+		ID string `json:"id"`
+	}
+	if err := json.Unmarshal(payload, &parsed); err != nil {
+		return errors.New("failed to parse the Drive upload response").Base(err)
+	}
+	if parsed.ID != "" {
+		s.rememberID(flat, parsed.ID)
+	}
+	return nil
+}
+
+func (s *driveStorage) Get(ctx context.Context, name string) ([]byte, error) {
+	flat := flatten(name)
+	id, err := s.resolveID(ctx, flat)
+	if err != nil {
+		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:
+		s.forgetID(flat)
+		return nil, errNotFound
+	default:
+		return nil, errors.New("Drive download of ", name, " answered ", status, ": ", string(payload))
+	}
+}
+
+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 {
+		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)
+	if err != nil {
+		return nil, errors.New("the inline data is not valid base64").Base(err)
+	}
+	return data, nil
+}
+
+func (s *driveStorage) deleteID(ctx context.Context, flat, id string) error {
+	status, payload, err := s.do(ctx, http.MethodDelete,
+		s.filesURL+"/"+url.PathEscape(id)+"?supportsAllDrives=true", "", nil)
+	if err != nil {
+		return err
+	}
+	s.forgetID(flat)
+	switch status {
+	case http.StatusOK, http.StatusNoContent, http.StatusNotFound:
+		return nil
+	default:
+		return errors.New("Drive deletion of ", flat, " answered ", status, ": ", string(payload))
+	}
+}
+
+func (s *driveStorage) Delete(ctx context.Context, name string) error {
+	flat := flatten(name)
+
+	if id, err := s.resolveID(ctx, flat); err == nil {
+		if err := s.deleteID(ctx, flat, id); err != nil {
+			return err
+		}
+	} else if err != errNotFound {
+		return err
+	}
+
+	children, err := s.query(ctx, "name contains '"+quoteDriveValue(flat+flatSeparator)+"'")
+	if err != nil {
+		return err
+	}
+	for childName, file := range children {
+		if err := s.deleteID(ctx, childName, file.id); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s *driveStorage) List(ctx context.Context, prefix string) ([]Entry, error) {
+	flat := flatten(prefix) + flatSeparator
+
+	found, err := s.query(ctx, "name contains '"+quoteDriveValue(flat)+"'")
+	if err != nil {
+		return nil, err
+	}
+
+	seen := make(map[string]bool, len(found))
+	entries := make([]Entry, 0, len(found))
+	for name, file := range found {
+		rest := strings.TrimPrefix(name, flat)
+		if rest == "" {
+			continue
+		}
+		direct := true
+		if cut := strings.Index(rest, flatSeparator); cut >= 0 {
+			rest = rest[:cut]
+			direct = false
+		}
+		if seen[rest] {
+			continue
+		}
+		seen[rest] = true
+
+		entry := Entry{Name: rest}
+		if direct && file.description != "" {
+			if data, err := base64.StdEncoding.DecodeString(file.description); err == nil {
+				entry.Inline = data
+			}
+		}
+		entries = append(entries, entry)
+	}
+	return entries, nil
+}
+
+func (s *driveStorage) Close() error {
+	return nil
+}

transport/internet/xdrive/drive_live_test.go

@@ -0,0 +1,345 @@
+package xdrive
+
+import (
+	"bytes"
+	"context"
+	"crypto/rand"
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/xtls/xray-core/transport/internet"
+)
+
+const liveSecretsEnv = "XRAY_XDRIVE_DRIVE_SECRETS"
+
+func liveDriveConfig(t *testing.T) *Config {
+	t.Helper()
+
+	path := os.Getenv(liveSecretsEnv)
+	if path == "" {
+		t.Skipf("set %s to run this test", liveSecretsEnv)
+	}
+
+	payload, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("reading %s: %v", path, err)
+	}
+	var secrets struct {
+		Folder       string `json:"folder"`
+		ClientID     string `json:"client_id"`
+		ClientSecret string `json:"client_secret"`
+		RefreshToken string `json:"refresh_token"`
+	}
+	if err := json.Unmarshal(payload, &secrets); err != nil {
+		t.Fatalf("parsing %s: %v", path, err)
+	}
+
+	config := &Config{
+		RemoteFolder:      secrets.Folder,
+		Service:           "Google Drive",
+		Secrets:           []string{secrets.ClientID, secrets.ClientSecret, secrets.RefreshToken},
+		SegmentBytes:      256 * 1024,
+		FlushIntervalMs:   100,
+		PollIntervalMs:    500,
+		MaxPollIntervalMs: 2000,
+		SessionTtlSeconds: 120,
+	}
+	if raw := os.Getenv("XRAY_XDRIVE_LIVE_SEGMENT"); raw != "" {
+		config.SegmentBytes = uint32(envInt(t, "XRAY_XDRIVE_LIVE_SEGMENT"))
+	}
+	if raw := os.Getenv("XRAY_XDRIVE_LIVE_CONCURRENCY"); raw != "" {
+		config.Concurrency = uint32(envInt(t, "XRAY_XDRIVE_LIVE_CONCURRENCY"))
+	}
+
+	storage, err := newDriveStorage(nil, config)
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	defer storage.Close()
+	for _, dir := range []string{sessionsDir, streamsDir} {
+		if err := storage.Delete(context.Background(), dir); err != nil {
+			t.Fatalf("clearing %s: %v", dir, err)
+		}
+	}
+
+	return config
+}
+
+func envInt(t *testing.T, name string) int {
+	t.Helper()
+
+	parsed, err := strconv.Atoi(os.Getenv(name))
+	if err != nil {
+		t.Fatalf("%s: %v", name, err)
+	}
+	return parsed
+}
+
+func TestLiveDriveStorage(t *testing.T) {
+	config := liveDriveConfig(t)
+	storage, err := newDriveStorage(nil, config)
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	defer storage.Close()
+
+	ctx := context.Background()
+	name := "streams/livetest/c2s/000000000.seg"
+	payload := []byte("xdrive over a real remote storage service")
+	defer storage.Delete(ctx, "streams/livetest")
+
+	start := time.Now()
+	if err := storage.Put(ctx, name, payload); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+	t.Logf("Put took %v", time.Since(start))
+
+	start = time.Now()
+	names, err := storage.List(ctx, "streams/livetest/c2s")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	t.Logf("List took %v", time.Since(start))
+	if len(names) != 1 || names[0].Name != "000000000.seg" {
+		t.Fatalf("List returned %v, want one segment", names)
+	}
+
+	start = time.Now()
+	got, err := storage.Get(ctx, name)
+	if err != nil {
+		t.Fatalf("Get: %v", err)
+	}
+	t.Logf("Get took %v", time.Since(start))
+	if !bytes.Equal(got, payload) {
+		t.Fatalf("Get returned %q, want %q", got, payload)
+	}
+
+	if _, err := storage.Get(ctx, "streams/livetest/c2s/000000009.seg"); err != errNotFound {
+		t.Fatalf("Get returned %v, want errNotFound", err)
+	}
+
+	if err := storage.Delete(ctx, "streams/livetest"); err != nil {
+		t.Fatalf("Delete: %v", err)
+	}
+	names, err = storage.List(ctx, "streams/livetest/c2s")
+	if err != nil {
+		t.Fatalf("List after delete: %v", err)
+	}
+	if len(names) != 0 {
+		t.Fatalf("List after delete returned %v", names)
+	}
+}
+
+func TestLiveDriveTransport(t *testing.T) {
+	config := liveDriveConfig(t)
+	streamSettings := &internet.MemoryStreamConfig{
+		ProtocolName:     protocolName,
+		ProtocolSettings: config,
+	}
+
+	client, server, cleanup := pairWith(t, streamSettings)
+	defer cleanup()
+
+	start := time.Now()
+	if _, err := client.Write([]byte("ping")); err != nil {
+		t.Fatalf("client write: %v", err)
+	}
+	expectRead(t, server, "ping")
+	t.Logf("client to server round took %v", time.Since(start))
+
+	start = time.Now()
+	if _, err := server.Write([]byte("pong")); err != nil {
+		t.Fatalf("server write: %v", err)
+	}
+	expectRead(t, client, "pong")
+	t.Logf("server to client round took %v", time.Since(start))
+
+	size := 400000
+	if raw := os.Getenv("XRAY_XDRIVE_LIVE_BYTES"); raw != "" {
+		parsed, err := strconv.Atoi(raw)
+		if err != nil {
+			t.Fatalf("XRAY_XDRIVE_LIVE_BYTES: %v", err)
+		}
+		size = parsed
+	}
+	payload := make([]byte, size)
+	if _, err := rand.Read(payload); err != nil {
+		t.Fatalf("rand: %v", err)
+	}
+
+	start = time.Now()
+	go func() {
+		client.Write(payload)
+	}()
+	if err := server.SetReadDeadline(time.Now().Add(5 * time.Minute)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	got := make([]byte, len(payload))
+	if _, err := io.ReadFull(server, got); err != nil {
+		t.Fatalf("ReadFull: %v", err)
+	}
+	elapsed := time.Since(start)
+	if !bytes.Equal(got, payload) {
+		t.Fatal("payload mismatch")
+	}
+	t.Logf("%d bytes took %v (%.1f KiB/s)", len(payload), elapsed,
+		float64(len(payload))/1024/elapsed.Seconds())
+}
+
+func TestLiveDriveParallelPut(t *testing.T) {
+	config := liveDriveConfig(t)
+	storage, err := newDriveStorage(nil, config)
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	defer storage.Close()
+
+	ctx := context.Background()
+	defer storage.Delete(ctx, "streams/benchtest")
+
+	chunk := make([]byte, 256*1024)
+	if _, err := rand.Read(chunk); err != nil {
+		t.Fatalf("rand: %v", err)
+	}
+
+	if err := storage.Put(ctx, "streams/benchtest/warmup", chunk); err != nil {
+		t.Fatalf("warmup: %v", err)
+	}
+
+	start := time.Now()
+	for i := 0; i < 4; i++ {
+		if err := storage.Put(ctx, fmt.Sprintf("streams/benchtest/seq%d", i), chunk); err != nil {
+			t.Fatalf("sequential put: %v", err)
+		}
+	}
+	sequential := time.Since(start)
+	t.Logf("4 sequential puts of 256 KiB: %v (%.1f KiB/s)",
+		sequential, float64(4*len(chunk))/1024/sequential.Seconds())
+
+	start = time.Now()
+	var wg sync.WaitGroup
+	failures := make([]error, 8)
+	for i := 0; i < 8; i++ {
+		wg.Add(1)
+		go func(i int) {
+			defer wg.Done()
+			failures[i] = storage.Put(ctx, fmt.Sprintf("streams/benchtest/par%d", i), chunk)
+		}(i)
+	}
+	wg.Wait()
+	parallel := time.Since(start)
+	for _, err := range failures {
+		if err != nil {
+			t.Fatalf("parallel put: %v", err)
+		}
+	}
+	t.Logf("8 parallel puts of 256 KiB: %v (%.1f KiB/s)",
+		parallel, float64(8*len(chunk))/1024/parallel.Seconds())
+
+	start = time.Now()
+	names, err := storage.List(ctx, "streams/benchtest")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	t.Logf("List of %d objects took %v", len(names), time.Since(start))
+
+	start = time.Now()
+	wg = sync.WaitGroup{}
+	for i := 0; i < 8; i++ {
+		wg.Add(1)
+		go func(i int) {
+			defer wg.Done()
+			storage.Get(ctx, fmt.Sprintf("streams/benchtest/par%d", i))
+		}(i)
+	}
+	wg.Wait()
+	download := time.Since(start)
+	t.Logf("8 parallel gets of 256 KiB: %v (%.1f KiB/s)",
+		download, float64(8*len(chunk))/1024/download.Seconds())
+}
+
+func TestLiveDriveSegmentSweep(t *testing.T) {
+	config := liveDriveConfig(t)
+	storage, err := newDriveStorage(nil, config)
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	defer storage.Close()
+
+	ctx := context.Background()
+	defer storage.Delete(ctx, "streams/sweeptest")
+
+	const total = 1024 * 1024
+	for _, size := range []int{64 * 1024, 128 * 1024, 256 * 1024, 512 * 1024} {
+		chunk := make([]byte, size)
+		if _, err := rand.Read(chunk); err != nil {
+			t.Fatalf("rand: %v", err)
+		}
+		count := total / size
+
+		start := time.Now()
+		var wg sync.WaitGroup
+		for i := 0; i < count; i++ {
+			wg.Add(1)
+			go func(i int) {
+				defer wg.Done()
+				storage.Put(ctx, fmt.Sprintf("streams/sweeptest/s%d-%d", size, i), chunk)
+			}(i)
+		}
+		wg.Wait()
+		elapsed := time.Since(start)
+
+		t.Logf("%4d KiB x %2d = 1 MiB in %8v -> %6.1f KiB/s",
+			size/1024, count, elapsed.Round(time.Millisecond),
+			float64(total)/1024/elapsed.Seconds())
+	}
+}
+
+func TestLiveDriveListLag(t *testing.T) {
+	config := liveDriveConfig(t)
+	storage, err := newDriveStorage(nil, config)
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	defer storage.Close()
+
+	ctx := context.Background()
+	defer storage.Delete(ctx, "streams/lagtest")
+
+	const rounds = 6
+	var worst time.Duration
+
+	for i := 0; i < rounds; i++ {
+		name := fmt.Sprintf("streams/lagtest/round%d/000000000.seg", i)
+		if err := storage.Put(ctx, name, []byte("probe")); err != nil {
+			t.Fatalf("Put: %v", err)
+		}
+
+		start := time.Now()
+		var lag time.Duration
+		for {
+			names, err := storage.List(ctx, fmt.Sprintf("streams/lagtest/round%d", i))
+			if err != nil {
+				t.Fatalf("List: %v", err)
+			}
+			if len(names) == 1 {
+				lag = time.Since(start)
+				break
+			}
+			if time.Since(start) > 30*time.Second {
+				t.Fatalf("round %d: the object never showed up in a listing", i)
+			}
+		}
+		if lag > worst {
+			worst = lag
+		}
+		t.Logf("round %d: the object became listable after %v", i, lag.Round(time.Millisecond))
+	}
+	t.Logf("worst listing lag: %v", worst.Round(time.Millisecond))
+}

transport/internet/xdrive/drive_test.go

@@ -0,0 +1,690 @@
+package xdrive
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"mime"
+	"mime/multipart"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet"
+)
+
+type fakeFile struct {
+	id          string
+	name        string
+	data        []byte
+	description string
+}
+
+type fakeDrive struct {
+	server *httptest.Server
+
+	mu         sync.Mutex
+	files      map[string]*fakeFile
+	nextID     int
+	failOnce   map[string]bool
+	failStatus map[string]int
+	failBody   map[string]string
+	tokens     int
+	hosts      map[string]bool
+}
+
+func newFakeDrive(t *testing.T) *fakeDrive {
+	t.Helper()
+
+	drive := &fakeDrive{
+		files:      make(map[string]*fakeFile),
+		failOnce:   make(map[string]bool),
+		failStatus: make(map[string]int),
+		failBody:   make(map[string]string),
+		hosts:      make(map[string]bool),
+	}
+	mux := http.NewServeMux()
+	mux.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.NotFound(w, r)
+	}))
+	record := func(next http.HandlerFunc) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			drive.mu.Lock()
+			drive.hosts[r.Host] = true
+			drive.mu.Unlock()
+			next(w, r)
+		}
+	}
+	mux.HandleFunc("/token", record(drive.handleToken))
+	mux.HandleFunc("/upload", record(drive.handleUpload))
+	mux.HandleFunc("/files", record(drive.handleFiles))
+	mux.HandleFunc("/files/", record(drive.handleFile))
+	drive.server = httptest.NewServer(mux)
+
+	resetSharedStorage()
+
+	previous := []string{driveTokenURL, driveFilesURL, driveUploadURL}
+	previousBackoff := driveInitialBackoff
+	driveTokenURL = drive.server.URL + "/token"
+	driveFilesURL = drive.server.URL + "/files"
+	driveUploadURL = drive.server.URL + "/upload"
+	driveInitialBackoff = 5 * time.Millisecond
+
+	t.Cleanup(func() {
+		driveTokenURL, driveFilesURL, driveUploadURL = previous[0], previous[1], previous[2]
+		driveInitialBackoff = previousBackoff
+		drive.server.Close()
+		resetSharedStorage()
+	})
+	return drive
+}
+
+func (d *fakeDrive) handleToken(w http.ResponseWriter, r *http.Request) {
+	d.mu.Lock()
+	d.tokens++
+	d.mu.Unlock()
+	json.NewEncoder(w).Encode(map[string]interface{}{
+		"access_token": "fake-token",
+		"expires_in":   3600,
+	})
+}
+
+func (d *fakeDrive) handleUpload(w http.ResponseWriter, r *http.Request) {
+	if d.shouldFail("upload") {
+		if status, body := d.failure("upload"); status != 0 {
+			w.WriteHeader(status)
+			w.Write([]byte(body))
+			return
+		}
+		w.WriteHeader(http.StatusTooManyRequests)
+		return
+	}
+
+	_, params, err := mime.ParseMediaType(r.Header.Get("Content-Type"))
+	if err != nil {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+	reader := multipart.NewReader(r.Body, params["boundary"])
+
+	metaPart, err := reader.NextPart()
+	if err != nil {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+	var metadata struct {
+		Name string `json:"name"`
+	}
+	if err := json.NewDecoder(metaPart).Decode(&metadata); err != nil {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	var data []byte
+	if dataPart, err := reader.NextPart(); err == nil {
+		data, _ = io.ReadAll(dataPart)
+	}
+
+	d.mu.Lock()
+	d.nextID++
+	id := fmt.Sprintf("id-%d", d.nextID)
+	d.files[id] = &fakeFile{id: id, name: metadata.Name, data: data}
+	d.mu.Unlock()
+
+	json.NewEncoder(w).Encode(map[string]string{"id": id, "name": metadata.Name})
+}
+
+func (d *fakeDrive) handleFiles(w http.ResponseWriter, r *http.Request) {
+	if r.Method == http.MethodPost {
+		d.handleCreate(w, r)
+		return
+	}
+	d.handleList(w, r)
+}
+
+func (d *fakeDrive) handleCreate(w http.ResponseWriter, r *http.Request) {
+	if d.shouldFail("upload") {
+		if status, body := d.failure("upload"); status != 0 {
+			w.WriteHeader(status)
+			w.Write([]byte(body))
+			return
+		}
+		w.WriteHeader(http.StatusTooManyRequests)
+		return
+	}
+
+	var meta struct {
+		Name        string `json:"name"`
+		Description string `json:"description"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&meta); err != nil {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	d.mu.Lock()
+	d.nextID++
+	id := fmt.Sprintf("id-%d", d.nextID)
+	d.files[id] = &fakeFile{id: id, name: meta.Name, description: meta.Description}
+	d.mu.Unlock()
+
+	json.NewEncoder(w).Encode(map[string]string{"id": id, "name": meta.Name})
+}
+
+func (d *fakeDrive) handleList(w http.ResponseWriter, r *http.Request) {
+	if d.shouldFail("list") {
+		w.WriteHeader(http.StatusServiceUnavailable)
+		return
+	}
+
+	query := r.URL.Query().Get("q")
+	exact, prefix := parseFakeQuery(query)
+
+	type entry struct {
+		ID          string `json:"id"`
+		Name        string `json:"name"`
+		Description string `json:"description,omitempty"`
+	}
+	result := struct {
+		Files []entry `json:"files"`
+	}{}
+
+	d.mu.Lock()
+	for _, file := range d.files {
+		match := false
+		switch {
+		case exact != "":
+			match = file.name == exact
+		case prefix != "":
+			match = strings.HasPrefix(file.name, prefix)
+		}
+		if match {
+			result.Files = append(result.Files, entry{
+				ID: file.id, Name: file.name, Description: file.description,
+			})
+		}
+	}
+	d.mu.Unlock()
+
+	json.NewEncoder(w).Encode(result)
+}
+
+func (d *fakeDrive) handleFile(w http.ResponseWriter, r *http.Request) {
+	id := strings.TrimPrefix(r.URL.Path, "/files/")
+
+	d.mu.Lock()
+	file, ok := d.files[id]
+	if ok && r.Method == http.MethodDelete {
+		delete(d.files, id)
+	}
+	d.mu.Unlock()
+
+	if !ok {
+		w.WriteHeader(http.StatusNotFound)
+		return
+	}
+	if r.Method == http.MethodDelete {
+		w.WriteHeader(http.StatusNoContent)
+		return
+	}
+	if strings.Contains(r.URL.RawQuery, "fields=description") {
+		json.NewEncoder(w).Encode(map[string]string{"description": file.description})
+		return
+	}
+	w.Write(file.data)
+}
+
+func (d *fakeDrive) shouldFail(kind string) bool {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	if d.failOnce[kind] {
+		d.failOnce[kind] = false
+		return true
+	}
+	return false
+}
+
+func (d *fakeDrive) failOnceWith(kind string, status int, body string) {
+	d.mu.Lock()
+	d.failOnce[kind] = true
+	d.failStatus[kind] = status
+	d.failBody[kind] = body
+	d.mu.Unlock()
+}
+
+func (d *fakeDrive) failure(kind string) (int, string) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	if status, ok := d.failStatus[kind]; ok {
+		return status, d.failBody[kind]
+	}
+	return 0, ""
+}
+
+func (d *fakeDrive) failNext(kind string) {
+	d.mu.Lock()
+	d.failOnce[kind] = true
+	d.mu.Unlock()
+}
+
+func (d *fakeDrive) seenHosts() []string {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	out := make([]string, 0, len(d.hosts))
+	for h := range d.hosts {
+		out = append(out, h)
+	}
+	return out
+}
+
+func (d *fakeDrive) count() int {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	return len(d.files)
+}
+
+func parseFakeQuery(query string) (exact, prefix string) {
+	if value, ok := cutQuoted(query, "name = '"); ok {
+		return value, ""
+	}
+	if value, ok := cutQuoted(query, "name contains '"); ok {
+		return "", value
+	}
+	return "", ""
+}
+
+func cutQuoted(query, marker string) (string, bool) {
+	start := strings.Index(query, marker)
+	if start < 0 {
+		return "", false
+	}
+	rest := query[start+len(marker):]
+	end := strings.Index(rest, "'")
+	if end < 0 {
+		return "", false
+	}
+	return rest[:end], true
+}
+
+func driveSettings() *internet.MemoryStreamConfig {
+	return &internet.MemoryStreamConfig{
+		ProtocolName: protocolName,
+		ProtocolSettings: &Config{
+			RemoteFolder:      "folder-id",
+			Service:           "Google Drive",
+			Secrets:           []string{"client", "secret", "refresh"},
+			FlushIntervalMs:   5,
+			PollIntervalMs:    5,
+			MaxPollIntervalMs: 20,
+			SessionTtlSeconds: 1,
+		},
+	}
+}
+
+func newDriveBackend(t *testing.T) *driveStorage {
+	t.Helper()
+
+	storage, err := newDriveStorage(driveSettings(), driveSettings().ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+	return storage
+}
+
+func TestDriveSecrets(t *testing.T) {
+	if _, err := newDriveStorage(nil, &Config{RemoteFolder: "f", Secrets: []string{"a", "b"}}); err == nil {
+		t.Fatal("accepted two secrets")
+	}
+	if _, err := newDriveStorage(nil, &Config{Secrets: []string{"a", "b", "c"}}); err == nil {
+		t.Fatal("accepted an empty remoteFolder")
+	}
+	if _, err := newDriveStorage(nil, &Config{RemoteFolder: "f", Secrets: []string{"a", "", "c"}}); err == nil {
+		t.Fatal("accepted an empty secret")
+	}
+}
+
+func TestDriveRoundTrip(t *testing.T) {
+	drive := newFakeDrive(t)
+	storage := newDriveBackend(t)
+	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 %q", data, "hello")
+	}
+
+	names, err := storage.List(ctx, "streams/abc/c2s")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(names) != 1 || names[0].Name != "000000000.seg" {
+		t.Fatalf("List returned %v, want 1 segment", names)
+	}
+
+	if _, err := storage.Get(ctx, "streams/abc/c2s/000000009.seg"); err != errNotFound {
+		t.Fatalf("Get returned %v, want errNotFound", err)
+	}
+
+	if err := storage.Delete(ctx, "streams/abc/c2s/000000000.seg"); err != nil {
+		t.Fatalf("Delete: %v", err)
+	}
+	if drive.count() != 0 {
+		t.Fatalf("fake drive still holds %d files", drive.count())
+	}
+}
+
+func TestDriveListChildren(t *testing.T) {
+	newFakeDrive(t)
+	storage := newDriveBackend(t)
+	ctx := context.Background()
+
+	for _, name := range []string{
+		"streams/one/c2s/000000000.seg",
+		"streams/one/s2c/000000000.seg",
+		"streams/two/c2s/000000000.seg",
+	} {
+		if err := storage.Put(ctx, name, []byte("x")); err != nil {
+			t.Fatalf("Put %s: %v", name, err)
+		}
+	}
+
+	names, err := storage.List(ctx, "streams")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(names) != 2 {
+		t.Fatalf("List returned %v, want 2 sessions", names)
+	}
+}
+
+func TestDriveDeleteSession(t *testing.T) {
+	drive := newFakeDrive(t)
+	storage := newDriveBackend(t)
+	ctx := context.Background()
+
+	for _, name := range []string{
+		"streams/one/c2s/000000000.seg",
+		"streams/one/c2s/000000001.end",
+		"streams/one/s2c/000000000.seg",
+		"streams/two/c2s/000000000.seg",
+	} {
+		if err := storage.Put(ctx, name, []byte("x")); err != nil {
+			t.Fatalf("Put %s: %v", name, err)
+		}
+	}
+
+	if err := storage.Delete(ctx, "streams/one"); err != nil {
+		t.Fatalf("Delete: %v", err)
+	}
+	if drive.count() != 1 {
+		t.Fatalf("fake drive holds %d files, want 1", drive.count())
+	}
+}
+
+func TestDriveRetry(t *testing.T) {
+	drive := newFakeDrive(t)
+	storage := newDriveBackend(t)
+	ctx := context.Background()
+
+	drive.failNext("upload")
+	if err := storage.Put(ctx, "sessions/abc", nil); err != nil {
+		t.Fatalf("Put did not survive a 429: %v", err)
+	}
+
+	drive.failNext("list")
+	if _, err := storage.List(ctx, "sessions"); err != nil {
+		t.Fatalf("List did not survive a 503: %v", err)
+	}
+}
+
+func TestDriveTokenCache(t *testing.T) {
+	drive := newFakeDrive(t)
+	storage := newDriveBackend(t)
+	ctx := context.Background()
+
+	for i := 0; i < 5; i++ {
+		if err := storage.Put(ctx, fmt.Sprintf("sessions/s%d", i), nil); err != nil {
+			t.Fatalf("Put: %v", err)
+		}
+	}
+	if drive.tokens != 1 {
+		t.Fatalf("token endpoint hit %d times, want 1", drive.tokens)
+	}
+}
+
+func TestDriveTransport(t *testing.T) {
+	newFakeDrive(t)
+
+	client, server, cleanup := pairWith(t, driveSettings())
+	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")
+}
+
+func TestDriveLargeTransfer(t *testing.T) {
+	newFakeDrive(t)
+
+	client, server, cleanup := pairWith(t, driveSettings())
+	defer cleanup()
+
+	payload := make([]byte, 300000)
+	for i := range payload {
+		payload[i] = byte(i % 251)
+	}
+
+	go func() {
+		client.Write(payload)
+	}()
+
+	if err := server.SetReadDeadline(time.Now().Add(60 * time.Second)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	got := make([]byte, len(payload))
+	if _, err := io.ReadFull(server, got); err != nil {
+		t.Fatalf("ReadFull: %v", err)
+	}
+	for i := range got {
+		if got[i] != payload[i] {
+			t.Fatalf("payload mismatch at byte %d", i)
+		}
+	}
+}
+
+func TestRateLimited(t *testing.T) {
+	limited := []string{
+		`{"error":{"code":403,"errors":[{"reason":"userRateLimitExceeded"}]}}`,
+		`{"error":{"code":403,"errors":[{"reason":"rateLimitExceeded"}]}}`,
+		`{"error":{"code":403,"errors":[{"reason":"sharingRateLimitExceeded"}]}}`,
+		`{"error":{"status":"RESOURCE_EXHAUSTED"}}`,
+	}
+	for _, payload := range limited {
+		if !rateLimited([]byte(payload)) {
+			t.Fatalf("rateLimited missed %s", payload)
+		}
+	}
+
+	permanent := []string{
+		`{"error":{"code":403,"errors":[{"reason":"insufficientFilePermissions"}]}}`,
+		`{"error":{"code":403,"errors":[{"reason":"storageQuotaExceeded"}]}}`,
+		`not json at all`,
+	}
+	for _, payload := range permanent {
+		if rateLimited([]byte(payload)) {
+			t.Fatalf("rateLimited treated %s as temporary", payload)
+		}
+	}
+}
+
+func TestDriveRetryRateLimit(t *testing.T) {
+	drive := newFakeDrive(t)
+	storage := newDriveBackend(t)
+
+	drive.failOnceWith("upload", http.StatusForbidden,
+		`{"error":{"code":403,"errors":[{"reason":"userRateLimitExceeded"}]}}`)
+
+	if err := storage.Put(context.Background(), "sessions/abc", nil); err != nil {
+		t.Fatalf("Put did not survive a 403: %v", err)
+	}
+}
+
+func TestDriveSharedClient(t *testing.T) {
+	newFakeDrive(t)
+
+	first, err := newStorage(driveSettings())
+	if err != nil {
+		t.Fatalf("newStorage: %v", err)
+	}
+	second, err := newStorage(driveSettings())
+	if err != nil {
+		t.Fatalf("newStorage: %v", err)
+	}
+	if first != second {
+		t.Fatal("same settings did not share one storage")
+	}
+}
+
+func TestDriveInlineListing(t *testing.T) {
+	drive := newFakeDrive(t)
+	storage := newDriveBackend(t)
+	ctx := context.Background()
+
+	payload := []byte("small enough to ride along with the listing")
+	if err := storage.Put(ctx, "streams/abc/c2s/000000000.seg", payload); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	entries, err := storage.List(ctx, "streams/abc/c2s")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(entries) != 1 {
+		t.Fatalf("List returned %v, want 1 entry", entries)
+	}
+	if string(entries[0].Inline) != string(payload) {
+		t.Fatalf("listing carried %q, want %q", entries[0].Inline, payload)
+	}
+
+	d := drive
+	d.mu.Lock()
+	var stored *fakeFile
+	for _, f := range d.files {
+		stored = f
+	}
+	d.mu.Unlock()
+	if len(stored.data) != 0 {
+		t.Fatal("small payload was uploaded as content")
+	}
+}
+
+func TestDriveLargeContent(t *testing.T) {
+	drive := newFakeDrive(t)
+	storage := newDriveBackend(t)
+	ctx := context.Background()
+
+	payload := make([]byte, driveInlineLimit+1)
+	for i := range payload {
+		payload[i] = byte(i)
+	}
+	if err := storage.Put(ctx, "streams/abc/c2s/000000000.seg", payload); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	entries, err := storage.List(ctx, "streams/abc/c2s")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(entries) != 1 || entries[0].Inline != nil {
+		t.Fatalf("large payload was inlined, got %v", entries)
+	}
+
+	got, err := storage.Get(ctx, "streams/abc/c2s/000000000.seg")
+	if err != nil {
+		t.Fatalf("Get: %v", err)
+	}
+	if len(got) != len(payload) {
+		t.Fatalf("Get returned %d bytes, want %d", len(got), len(payload))
+	}
+	_ = drive
+}
+
+func TestDriveInlineGet(t *testing.T) {
+	newFakeDrive(t)
+	storage := newDriveBackend(t)
+	ctx := context.Background()
+
+	payload := []byte("only in the description")
+	if err := storage.Put(ctx, "sessions/abc", payload); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	got, err := storage.Get(ctx, "sessions/abc")
+	if err != nil {
+		t.Fatalf("Get: %v", err)
+	}
+	if string(got) != string(payload) {
+		t.Fatalf("Get returned %q, want %q", got, payload)
+	}
+}
+
+func TestDriveFronting(t *testing.T) {
+	drive := newFakeDrive(t)
+
+	fake, err := url.Parse(drive.server.URL)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	port, err := net.PortFromString(fake.Port())
+	if err != nil {
+		t.Fatalf("port: %v", err)
+	}
+
+	driveTokenURL = "http://www.googleapis.com/token"
+	driveFilesURL = "http://www.googleapis.com/files"
+	driveUploadURL = "http://www.googleapis.com/upload"
+
+	settings := driveSettings()
+	settings.Destination = &net.Destination{
+		Address: net.ParseAddress(fake.Hostname()),
+		Port:    port,
+		Network: net.Network_TCP,
+	}
+
+	storage, err := newDriveStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newDriveStorage: %v", err)
+	}
+
+	if err := storage.Put(context.Background(), "sessions/fronted", []byte("x")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+	if drive.count() != 1 {
+		t.Fatalf("fake drive holds %d files, want 1", drive.count())
+	}
+
+	for _, host := range drive.seenHosts() {
+		if host != "www.googleapis.com" {
+			t.Fatalf("inner host was %q, want www.googleapis.com regardless of address", host)
+		}
+	}
+}

transport/internet/xdrive/jsonpath.go

@@ -0,0 +1,39 @@
+package xdrive
+
+import (
+	"encoding/json"
+	"strings"
+)
+
+func jsonWalk(payload []byte, path string) interface{} {
+	var root interface{}
+	if json.Unmarshal(payload, &root) != nil {
+		return nil
+	}
+	node := root
+	for _, key := range strings.Split(path, ".") {
+		obj, ok := node.(map[string]interface{})
+		if !ok {
+			return nil
+		}
+		node, ok = obj[key]
+		if !ok {
+			return nil
+		}
+	}
+	return node
+}
+
+func jsonString(payload []byte, path string) string {
+	if s, ok := jsonWalk(payload, path).(string); ok {
+		return s
+	}
+	return ""
+}
+
+func jsonNumber(payload []byte, path string) int64 {
+	if f, ok := jsonWalk(payload, path).(float64); ok {
+		return int64(f)
+	}
+	return 0
+}

transport/internet/xdrive/local.go

@@ -0,0 +1,120 @@
+package xdrive
+
+import (
+	"context"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"github.com/xtls/xray-core/common/errors"
+)
+
+const tempPrefix = ".xdrive-tmp-"
+
+type localStorage struct {
+	root string
+}
+
+func newLocalStorage(root string) (*localStorage, error) {
+	if root == "" {
+		return nil, errors.New(`empty "remoteFolder"`)
+	}
+	if err := os.MkdirAll(root, 0o700); err != nil {
+		return nil, errors.New("failed to create remote folder").Base(err)
+	}
+	return &localStorage{root: root}, nil
+}
+
+func (s *localStorage) resolve(name string) (string, error) {
+	clean := path.Clean("/" + name)
+	if clean == "/" {
+		return "", errors.New("invalid object name: ", name)
+	}
+	if strings.HasPrefix(path.Base(clean), tempPrefix) {
+		return "", errors.New("reserved object name: ", name)
+	}
+	return filepath.Join(s.root, filepath.FromSlash(clean[1:])), nil
+}
+
+func (s *localStorage) Put(ctx context.Context, name string, data []byte) error {
+	full, err := s.resolve(name)
+	if err != nil {
+		return err
+	}
+	dir := filepath.Dir(full)
+	if err := os.MkdirAll(dir, 0o700); err != nil {
+		return errors.New("failed to create folder ", dir).Base(err)
+	}
+
+	tmp, err := os.CreateTemp(dir, tempPrefix+"*")
+	if err != nil {
+		return errors.New("failed to create temp file in ", dir).Base(err)
+	}
+	tmpName := tmp.Name()
+	defer os.Remove(tmpName)
+
+	if _, err := tmp.Write(data); err != nil {
+		tmp.Close()
+		return errors.New("failed to write ", name).Base(err)
+	}
+	if err := tmp.Close(); err != nil {
+		return errors.New("failed to close ", name).Base(err)
+	}
+	if err := os.Rename(tmpName, full); err != nil {
+		return errors.New("failed to commit ", name).Base(err)
+	}
+	return nil
+}
+
+func (s *localStorage) Get(ctx context.Context, name string) ([]byte, error) {
+	full, err := s.resolve(name)
+	if err != nil {
+		return nil, err
+	}
+	data, err := os.ReadFile(full)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, errNotFound
+		}
+		return nil, errors.New("failed to read ", name).Base(err)
+	}
+	return data, nil
+}
+
+func (s *localStorage) Delete(ctx context.Context, name string) error {
+	full, err := s.resolve(name)
+	if err != nil {
+		return err
+	}
+	if err := os.RemoveAll(full); err != nil {
+		return errors.New("failed to delete ", name).Base(err)
+	}
+	return nil
+}
+
+func (s *localStorage) List(ctx context.Context, prefix string) ([]Entry, error) {
+	full, err := s.resolve(prefix)
+	if err != nil {
+		return nil, err
+	}
+	entries, err := os.ReadDir(full)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, nil
+		}
+		return nil, errors.New("failed to list ", prefix).Base(err)
+	}
+	found := make([]Entry, 0, len(entries))
+	for _, entry := range entries {
+		if strings.HasPrefix(entry.Name(), tempPrefix) {
+			continue
+		}
+		found = append(found, Entry{Name: entry.Name()})
+	}
+	return found, nil
+}
+
+func (s *localStorage) Close() error {
+	return nil
+}

transport/internet/xdrive/params.go

@@ -0,0 +1,69 @@
+package xdrive
+
+import "time"
+
+const (
+	defaultSegmentBytes    = 512 * 1024
+	defaultFlushInterval   = 20 * time.Millisecond
+	defaultMinPollInterval = 50 * time.Millisecond
+	defaultMaxPollInterval = 500 * time.Millisecond
+	defaultEagerWindow     = 2 * time.Second
+	defaultHoleTimeout     = 30 * time.Second
+	defaultSessionTTL      = 5 * time.Minute
+	defaultConcurrency     = 8
+
+	maxSegmentBytes = 16 * 1024 * 1024
+	maxConcurrency  = 64
+)
+
+type params struct {
+	segmentBytes    int
+	flushInterval   time.Duration
+	minPollInterval time.Duration
+	maxPollInterval time.Duration
+	eagerWindow     time.Duration
+	holeTimeout     time.Duration
+	sessionTTL      time.Duration
+	concurrency     int
+}
+
+func millis(value uint32, fallback time.Duration) time.Duration {
+	if value == 0 {
+		return fallback
+	}
+	return time.Duration(value) * time.Millisecond
+}
+
+func seconds(value uint32, fallback time.Duration) time.Duration {
+	if value == 0 {
+		return fallback
+	}
+	return time.Duration(value) * time.Second
+}
+
+func capped(value uint32, fallback, limit int) int {
+	if value == 0 {
+		return fallback
+	}
+	if int(value) > limit {
+		return limit
+	}
+	return int(value)
+}
+
+func paramsFromConfig(c *Config) params {
+	p := params{
+		segmentBytes:    capped(c.SegmentBytes, defaultSegmentBytes, maxSegmentBytes),
+		flushInterval:   millis(c.FlushIntervalMs, defaultFlushInterval),
+		minPollInterval: millis(c.PollIntervalMs, defaultMinPollInterval),
+		maxPollInterval: millis(c.MaxPollIntervalMs, defaultMaxPollInterval),
+		eagerWindow:     millis(c.EagerWindowMs, defaultEagerWindow),
+		holeTimeout:     millis(c.HoleTimeoutMs, defaultHoleTimeout),
+		sessionTTL:      seconds(c.SessionTtlSeconds, defaultSessionTTL),
+		concurrency:     capped(c.Concurrency, defaultConcurrency, maxConcurrency),
+	}
+	if p.maxPollInterval < p.minPollInterval {
+		p.maxPollInterval = p.minPollInterval
+	}
+	return p
+}

transport/internet/xdrive/storage.go

@@ -0,0 +1,90 @@
+package xdrive
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"strings"
+	"sync"
+
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/transport/internet"
+)
+
+var errNotFound = errors.New("object not found")
+
+type Entry struct {
+	Name   string
+	Inline []byte
+}
+
+type Storage interface {
+	Put(ctx context.Context, name string, data []byte) error
+	Get(ctx context.Context, name string) ([]byte, error)
+	Delete(ctx context.Context, name string) error
+	List(ctx context.Context, prefix string) ([]Entry, error)
+	Close() error
+}
+
+func newStorage(streamSettings *internet.MemoryStreamConfig) (Storage, error) {
+	config, err := streamConfig(streamSettings)
+	if err != nil {
+		return nil, err
+	}
+
+	switch config.Service {
+	case "local":
+		return newLocalStorage(config.RemoteFolder)
+	case "Google Drive":
+		return sharedStorage(streamSettings, config, func() (Storage, error) {
+			return newDriveStorage(streamSettings, config)
+		})
+	case "template":
+		return sharedStorage(streamSettings, config, func() (Storage, error) {
+			return newTemplateStorage(streamSettings, config)
+		})
+	default:
+		return nil, errors.New("unsupported service: ", config.Service)
+	}
+}
+
+var (
+	sharedMu sync.Mutex
+	shared   = make(map[string]Storage)
+)
+
+func shareKey(streamSettings *internet.MemoryStreamConfig, config *Config) string {
+	parts := []string{config.Service, config.RemoteFolder}
+	parts = append(parts, config.Secrets...)
+	if streamSettings != nil {
+		parts = append(parts, streamSettings.SecurityType)
+		if streamSettings.Destination != nil {
+			parts = append(parts, streamSettings.Destination.NetAddr())
+		}
+	}
+	sum := sha256.Sum256([]byte(strings.Join(parts, "\x00")))
+	return hex.EncodeToString(sum[:])
+}
+
+func resetSharedStorage() {
+	sharedMu.Lock()
+	shared = make(map[string]Storage)
+	sharedMu.Unlock()
+}
+
+func sharedStorage(streamSettings *internet.MemoryStreamConfig, config *Config, build func() (Storage, error)) (Storage, error) {
+	key := shareKey(streamSettings, config)
+
+	sharedMu.Lock()
+	defer sharedMu.Unlock()
+
+	if storage, ok := shared[key]; ok {
+		return storage, nil
+	}
+	storage, err := build()
+	if err != nil {
+		return nil, err
+	}
+	shared[key] = storage
+	return storage, nil
+}

transport/internet/xdrive/template.go

@@ -0,0 +1,445 @@
+package xdrive
+
+import (
+	"bytes"
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"io"
+	"net/http"
+	"regexp"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/transport/internet"
+)
+
+type authTemplate struct {
+	Type       string            `json:"type"`
+	Header     map[string]string `json:"header"`
+	Username   string            `json:"username"`
+	Password   string            `json:"password"`
+	TokenURL   string            `json:"tokenUrl"`
+	Form       map[string]string `json:"form"`
+	TokenPath  string            `json:"tokenPath"`
+	ExpiryPath string            `json:"expiryPath"`
+}
+
+type opTemplate struct {
+	Method     string            `json:"method"`
+	URL        string            `json:"url"`
+	Headers    map[string]string `json:"headers"`
+	Body       string            `json:"body"`
+	NamesRegex string            `json:"namesRegex"`
+}
+
+type retryTemplate struct {
+	Status     []int  `json:"status"`
+	RateReason string `json:"rateReason"`
+}
+
+type storageTemplate struct {
+	Flatten     bool          `json:"flatten"`
+	Concurrency int           `json:"concurrency"`
+	Auth        authTemplate  `json:"auth"`
+	Put         opTemplate    `json:"put"`
+	Get         opTemplate    `json:"get"`
+	Delete      opTemplate    `json:"delete"`
+	List        opTemplate    `json:"list"`
+	Retry       retryTemplate `json:"retry"`
+
+	names *regexp.Regexp
+}
+
+type templateStorage struct {
+	tmpl    *storageTemplate
+	client  *http.Client
+	folder  string
+	secrets []string
+
+	inflight chan struct{}
+
+	tokenMu     sync.Mutex
+	token       string
+	tokenExpiry time.Time
+}
+
+func newTemplateStorage(streamSettings *internet.MemoryStreamConfig, config *Config) (*templateStorage, error) {
+	tmpl := &storageTemplate{}
+	if err := json.Unmarshal([]byte(config.Template), tmpl); err != nil {
+		return nil, errors.New("invalid template").Base(err)
+	}
+	if tmpl.Put.URL == "" || tmpl.Get.URL == "" || tmpl.List.URL == "" || tmpl.Delete.URL == "" {
+		return nil, errors.New("template needs put, get, list and delete operations")
+	}
+	if tmpl.List.NamesRegex == "" {
+		return nil, errors.New("template list needs a namesRegex")
+	}
+	re, err := regexp.Compile(tmpl.List.NamesRegex)
+	if err != nil {
+		return nil, errors.New("bad namesRegex").Base(err)
+	}
+	if re.NumSubexp() < 1 {
+		return nil, errors.New("namesRegex needs one capture group")
+	}
+	tmpl.names = re
+
+	conc := tmpl.Concurrency
+	if conc <= 0 {
+		conc = driveMaxInflight
+	}
+	if conc > maxTemplateConcurrency {
+		conc = maxTemplateConcurrency
+	}
+
+	return &templateStorage{
+		tmpl:     tmpl,
+		client:   newServiceClient(streamSettings, driveTimeout, conc),
+		folder:   config.RemoteFolder,
+		secrets:  config.Secrets,
+		inflight: make(chan struct{}, conc),
+	}, nil
+}
+
+const maxTemplateConcurrency = 256
+
+func (s *templateStorage) baseVars() map[string]string {
+	vars := map[string]string{"folder": s.folder}
+	for i, secret := range s.secrets {
+		vars["secret"+itoa(i)] = secret
+	}
+	return vars
+}
+
+func subst(tmpl string, vars map[string]string) string {
+	if tmpl == "" || !strings.ContainsRune(tmpl, '{') {
+		return tmpl
+	}
+	out := tmpl
+	for k, v := range vars {
+		out = strings.ReplaceAll(out, "{"+k+"}", v)
+	}
+	return out
+}
+
+func itoa(i int) string {
+	if i == 0 {
+		return "0"
+	}
+	var b [20]byte
+	pos := len(b)
+	for i > 0 {
+		pos--
+		b[pos] = byte('0' + i%10)
+		i /= 10
+	}
+	return string(b[pos:])
+}
+
+func (s *templateStorage) storedName(name string) string {
+	if s.tmpl.Flatten {
+		return flatten(name)
+	}
+	return name
+}
+
+func (s *templateStorage) retryable(status int, payload []byte) bool {
+	for _, code := range s.tmpl.Retry.Status {
+		if status == code {
+			return true
+		}
+	}
+	if status == http.StatusForbidden && s.tmpl.Retry.RateReason != "" {
+		if reason := jsonString(payload, s.tmpl.Retry.RateReason); reason != "" {
+			return true
+		}
+	}
+	return false
+}
+
+func (s *templateStorage) authHeaders(ctx context.Context, vars map[string]string) (map[string]string, error) {
+	switch s.tmpl.Auth.Type {
+	case "", "none":
+		return nil, nil
+	case "static", "oauth2":
+		if s.tmpl.Auth.Type == "oauth2" {
+			token, err := s.accessToken(ctx)
+			if err != nil {
+				return nil, err
+			}
+			vars["token"] = token
+		}
+		headers := make(map[string]string, len(s.tmpl.Auth.Header))
+		for k, v := range s.tmpl.Auth.Header {
+			headers[k] = subst(v, vars)
+		}
+		return headers, nil
+	case "basic":
+		user := subst(s.tmpl.Auth.Username, vars)
+		pass := subst(s.tmpl.Auth.Password, vars)
+		enc := base64.StdEncoding.EncodeToString([]byte(user + ":" + pass))
+		return map[string]string{"Authorization": "Basic " + enc}, nil
+	default:
+		return nil, errors.New("unsupported auth type: ", s.tmpl.Auth.Type)
+	}
+}
+
+func (s *templateStorage) accessToken(ctx context.Context) (string, error) {
+	s.tokenMu.Lock()
+	defer s.tokenMu.Unlock()
+
+	if s.token != "" && time.Now().Before(s.tokenExpiry) {
+		return s.token, nil
+	}
+
+	form := make(map[string]string, len(s.tmpl.Auth.Form))
+	vars := s.baseVars()
+	values := strings.Builder{}
+	first := true
+	for k, v := range s.tmpl.Auth.Form {
+		form[k] = subst(v, vars)
+		if !first {
+			values.WriteByte('&')
+		}
+		first = false
+		values.WriteString(k)
+		values.WriteByte('=')
+		values.WriteString(form[k])
+	}
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, s.tmpl.Auth.TokenURL,
+		strings.NewReader(values.String()))
+	if err != nil {
+		return "", errors.New("failed to build the token request").Base(err)
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+
+	resp, err := s.client.Do(req)
+	if err != nil {
+		return "", errors.New("failed to fetch the token").Base(err)
+	}
+	defer resp.Body.Close()
+	payload, err := io.ReadAll(io.LimitReader(resp.Body, 1<<20))
+	if err != nil {
+		return "", errors.New("failed to read the token response").Base(err)
+	}
+	if resp.StatusCode != http.StatusOK {
+		return "", errors.New("the token endpoint answered ", resp.StatusCode, ": ", string(payload))
+	}
+
+	path := s.tmpl.Auth.TokenPath
+	if path == "" {
+		path = "access_token"
+	}
+	token := jsonString(payload, path)
+	if token == "" {
+		return "", errors.New("the token response has no token at ", path)
+	}
+
+	lifetime := int64(3600)
+	if s.tmpl.Auth.ExpiryPath != "" {
+		if n := jsonNumber(payload, s.tmpl.Auth.ExpiryPath); n > 0 {
+			lifetime = n
+		}
+	}
+	if lifetime > 60 {
+		lifetime -= 60
+	}
+	s.token = token
+	s.tokenExpiry = time.Now().Add(time.Duration(lifetime) * time.Second)
+	return s.token, nil
+}
+
+func (s *templateStorage) invalidateToken() {
+	s.tokenMu.Lock()
+	s.token = ""
+	s.tokenMu.Unlock()
+}
+
+func (s *templateStorage) do(ctx context.Context, op *opTemplate, vars map[string]string, body []byte) (int, []byte, error) {
+	backoff := driveInitialBackoff
+	var lastErr error
+
+	for attempt := 0; attempt < driveMaxAttempts; attempt++ {
+		if attempt > 0 {
+			select {
+			case <-ctx.Done():
+				return 0, nil, ctx.Err()
+			case <-time.After(jitter(backoff)):
+			}
+			backoff *= 2
+			if backoff > driveMaxBackoff {
+				backoff = driveMaxBackoff
+			}
+		}
+
+		authHeaders, err := s.authHeaders(ctx, vars)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+
+		method := op.Method
+		if method == "" {
+			method = http.MethodGet
+		}
+
+		var reader io.Reader
+		if body != nil {
+			reader = bytes.NewReader(body)
+		}
+		req, err := http.NewRequestWithContext(ctx, method, subst(op.URL, vars), reader)
+		if err != nil {
+			return 0, nil, errors.New("failed to build request").Base(err)
+		}
+		for k, v := range authHeaders {
+			req.Header.Set(k, v)
+		}
+		for k, v := range op.Headers {
+			req.Header.Set(k, subst(v, vars))
+		}
+
+		select {
+		case s.inflight <- struct{}{}:
+		case <-ctx.Done():
+			return 0, nil, ctx.Err()
+		}
+		resp, err := s.client.Do(req)
+		<-s.inflight
+		if err != nil {
+			if ctx.Err() != nil {
+				return 0, nil, ctx.Err()
+			}
+			lastErr = errors.New("request failed").Base(err)
+			continue
+		}
+		payload, err := io.ReadAll(resp.Body)
+		resp.Body.Close()
+		if err != nil {
+			if ctx.Err() != nil {
+				return 0, nil, ctx.Err()
+			}
+			lastErr = errors.New("failed to read response").Base(err)
+			continue
+		}
+
+		if resp.StatusCode == http.StatusUnauthorized && s.tmpl.Auth.Type == "oauth2" {
+			s.invalidateToken()
+			lastErr = errors.New("the service rejected the token")
+			continue
+		}
+		if s.retryable(resp.StatusCode, payload) {
+			lastErr = errors.New("the service answered ", resp.StatusCode)
+			continue
+		}
+		return resp.StatusCode, payload, nil
+	}
+	return 0, nil, lastErr
+}
+
+func (s *templateStorage) Put(ctx context.Context, name string, data []byte) error {
+	vars := s.baseVars()
+	vars["name"] = s.storedName(name)
+
+	body := data
+	if s.tmpl.Put.Body != "" {
+		vars["data"] = base64.StdEncoding.EncodeToString(data)
+		body = []byte(subst(s.tmpl.Put.Body, vars))
+	}
+
+	status, payload, err := s.do(ctx, &s.tmpl.Put, vars, body)
+	if err != nil {
+		return err
+	}
+	if status < 200 || status >= 300 {
+		return errors.New("put of ", name, " answered ", status, ": ", string(payload))
+	}
+	return nil
+}
+
+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)
+	if err != nil {
+		return nil, err
+	}
+	switch {
+	case status >= 200 && status < 300:
+		return payload, nil
+	case status == http.StatusNotFound:
+		return nil, errNotFound
+	default:
+		return nil, errors.New("get of ", name, " answered ", status, ": ", string(payload))
+	}
+}
+
+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)
+	if err != nil {
+		return err
+	}
+	if status == http.StatusNotFound || (status >= 200 && status < 300) {
+		return nil
+	}
+	return errors.New("delete of ", name, " answered ", status, ": ", string(payload))
+}
+
+func (s *templateStorage) List(ctx context.Context, prefix string) ([]Entry, error) {
+	vars := s.baseVars()
+	flat := s.storedName(prefix)
+	vars["prefix"] = flat
+
+	status, payload, err := s.do(ctx, &s.tmpl.List, vars, nil)
+	if err != nil {
+		return nil, err
+	}
+	if status == http.StatusNotFound {
+		return nil, nil
+	}
+	if status < 200 || status >= 300 {
+		return nil, errors.New("list of ", prefix, " answered ", status, ": ", string(payload))
+	}
+
+	matches := s.tmpl.names.FindAllStringSubmatch(string(payload), -1)
+	if !s.tmpl.Flatten {
+		entries := make([]Entry, 0, len(matches))
+		for _, m := range matches {
+			entries = append(entries, Entry{Name: m[1]})
+		}
+		return entries, nil
+	}
+
+	want := flat + flatSeparator
+	seen := make(map[string]bool, len(matches))
+	entries := make([]Entry, 0, len(matches))
+	for _, m := range matches {
+		name := m[1]
+		if !strings.HasPrefix(name, want) {
+			continue
+		}
+		rest := strings.TrimPrefix(name, want)
+		if rest == "" {
+			continue
+		}
+		if cut := strings.Index(rest, flatSeparator); cut >= 0 {
+			rest = rest[:cut]
+		}
+		if seen[rest] {
+			continue
+		}
+		seen[rest] = true
+		entries = append(entries, Entry{Name: rest})
+	}
+	return entries, nil
+}
+
+func (s *templateStorage) Close() error {
+	return nil
+}

transport/internet/xdrive/template_test.go

@@ -0,0 +1,308 @@
+package xdrive
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/xtls/xray-core/transport/internet"
+)
+
+type fakeStore struct {
+	server *httptest.Server
+
+	mu       sync.Mutex
+	objects  map[string][]byte
+	needAuth string
+	sawAuth  string
+	tokens   int
+}
+
+func newFakeStore(t *testing.T) *fakeStore {
+	t.Helper()
+
+	store := &fakeStore{objects: make(map[string][]byte)}
+	store.server = httptest.NewServer(http.HandlerFunc(store.handle))
+	t.Cleanup(store.server.Close)
+	return store
+}
+
+func (s *fakeStore) handle(w http.ResponseWriter, r *http.Request) {
+	if r.URL.Path == "/token" {
+		s.mu.Lock()
+		s.tokens++
+		s.mu.Unlock()
+		json.NewEncoder(w).Encode(map[string]interface{}{
+			"access_token": "tok-fake", "expires_in": 3600,
+		})
+		return
+	}
+
+	if auth := r.Header.Get("Authorization"); auth != "" {
+		s.mu.Lock()
+		s.sawAuth = auth
+		s.mu.Unlock()
+	}
+	if s.needAuth != "" && r.Header.Get("Authorization") != s.needAuth {
+		w.WriteHeader(http.StatusUnauthorized)
+		return
+	}
+
+	key := strings.TrimPrefix(r.URL.Path, "/folder/")
+
+	switch r.Method {
+	case "PROPFIND":
+		s.mu.Lock()
+		var b strings.Builder
+		for name := range s.objects {
+			fmt.Fprintf(&b, "<d:href>/folder/%s</d:href>\n", name)
+		}
+		s.mu.Unlock()
+		w.Write([]byte(b.String()))
+	case http.MethodPut:
+		body, _ := io.ReadAll(r.Body)
+		s.mu.Lock()
+		s.objects[key] = body
+		s.mu.Unlock()
+		w.WriteHeader(http.StatusCreated)
+	case http.MethodGet:
+		s.mu.Lock()
+		data, ok := s.objects[key]
+		s.mu.Unlock()
+		if !ok {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		w.Write(data)
+	case http.MethodDelete:
+		s.mu.Lock()
+		delete(s.objects, key)
+		s.mu.Unlock()
+		w.WriteHeader(http.StatusNoContent)
+	default:
+		w.WriteHeader(http.StatusMethodNotAllowed)
+	}
+}
+
+func (s *fakeStore) count() int {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return len(s.objects)
+}
+
+func (s *fakeStore) seenAuth() string {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.sawAuth
+}
+
+func templateSettings(store *fakeStore, auth map[string]interface{}, secrets []string) *internet.MemoryStreamConfig {
+	base := store.server.URL
+	tmpl := map[string]interface{}{
+		"flatten": true,
+		"auth":    auth,
+		"put":     map[string]interface{}{"method": "PUT", "url": base + "/folder/{name}"},
+		"get":     map[string]interface{}{"method": "GET", "url": base + "/folder/{name}"},
+		"delete":  map[string]interface{}{"method": "DELETE", "url": base + "/folder/{name}"},
+		"list": map[string]interface{}{
+			"method":     "PROPFIND",
+			"url":        base + "/folder/",
+			"namesRegex": `<d:href>/folder/([^<]+)</d:href>`,
+		},
+		"retry": map[string]interface{}{"status": []int{429, 500, 502, 503}},
+	}
+	raw, _ := json.Marshal(tmpl)
+	return &internet.MemoryStreamConfig{
+		ProtocolName: protocolName,
+		ProtocolSettings: &Config{
+			RemoteFolder:      "folder",
+			Service:           "template",
+			Secrets:           secrets,
+			Template:          string(raw),
+			FlushIntervalMs:   5,
+			PollIntervalMs:    5,
+			MaxPollIntervalMs: 20,
+			SessionTtlSeconds: 5,
+		},
+	}
+}
+
+func newTemplateBackend(t *testing.T, store *fakeStore, auth map[string]interface{}, secrets []string) *templateStorage {
+	t.Helper()
+	settings := templateSettings(store, auth, secrets)
+	storage, err := newTemplateStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newTemplateStorage: %v", err)
+	}
+	return storage
+}
+
+func TestTemplateRoundTrip(t *testing.T) {
+	store := newFakeStore(t)
+	storage := newTemplateBackend(t, store, map[string]interface{}{"type": "none"}, nil)
+	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)
+	}
+
+	entries, err := storage.List(ctx, "streams/abc/c2s")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(entries) != 1 || entries[0].Name != "000000000.seg" {
+		t.Fatalf("List returned %v, want one segment", entries)
+	}
+
+	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 err := storage.Delete(ctx, "streams/abc/c2s/000000000.seg"); err != nil {
+		t.Fatalf("Delete: %v", err)
+	}
+	if store.count() != 0 {
+		t.Fatalf("store still holds %d objects", store.count())
+	}
+}
+
+func TestTemplateListReturnsDirectChildren(t *testing.T) {
+	store := newFakeStore(t)
+	storage := newTemplateBackend(t, store, map[string]interface{}{"type": "none"}, nil)
+	ctx := context.Background()
+
+	for _, name := range []string{
+		"streams/one/c2s/000000000.seg",
+		"streams/one/s2c/000000000.seg",
+		"streams/two/c2s/000000000.seg",
+	} {
+		if err := storage.Put(ctx, name, []byte("x")); err != nil {
+			t.Fatalf("Put %s: %v", name, err)
+		}
+	}
+
+	entries, err := storage.List(ctx, "streams")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(entries) != 2 {
+		t.Fatalf("List returned %v, want the two session ids", entries)
+	}
+}
+
+func TestTemplateBasicAuth(t *testing.T) {
+	store := newFakeStore(t)
+	store.needAuth = "Basic dXNlcjpwYXNz"
+	auth := map[string]interface{}{"type": "basic", "username": "{secret0}", "password": "{secret1}"}
+	storage := newTemplateBackend(t, store, auth, []string{"user", "pass"})
+
+	if err := storage.Put(context.Background(), "sessions/a", []byte("x")); err != nil {
+		t.Fatalf("Put with basic auth: %v", err)
+	}
+	if store.seenAuth() != "Basic dXNlcjpwYXNz" {
+		t.Fatalf("server saw auth %q", store.seenAuth())
+	}
+}
+
+func TestTemplateOAuth(t *testing.T) {
+	store := newFakeStore(t)
+	store.needAuth = "Bearer tok-fake"
+	auth := map[string]interface{}{
+		"type":     "oauth2",
+		"tokenUrl": store.server.URL + "/token",
+		"form":     map[string]interface{}{"grant_type": "refresh_token", "refresh_token": "{secret0}"},
+		"header":   map[string]interface{}{"Authorization": "Bearer {token}"},
+	}
+	storage := newTemplateBackend(t, store, auth, []string{"refresh"})
+	ctx := context.Background()
+
+	for i := 0; i < 4; i++ {
+		if err := storage.Put(ctx, fmt.Sprintf("sessions/s%d", i), nil); err != nil {
+			t.Fatalf("Put: %v", err)
+		}
+	}
+	if store.tokens != 1 {
+		t.Fatalf("token endpoint was hit %d times, want 1", store.tokens)
+	}
+}
+
+func TestTemplateTransport(t *testing.T) {
+	store := newFakeStore(t)
+	settings := templateSettings(store, map[string]interface{}{"type": "none"}, nil)
+
+	client, server, cleanup := pairWith(t, settings)
+	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")
+
+	payload := make([]byte, 300000)
+	for i := range payload {
+		payload[i] = byte(i % 251)
+	}
+	go func() { client.Write(payload) }()
+
+	if err := server.SetReadDeadline(time.Now().Add(30 * time.Second)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	got := make([]byte, len(payload))
+	if _, err := io.ReadFull(server, got); err != nil {
+		t.Fatalf("ReadFull: %v", err)
+	}
+	for i := range got {
+		if got[i] != payload[i] {
+			t.Fatalf("payload mismatch at byte %d", i)
+		}
+	}
+}
+
+func TestTemplateConcurrency(t *testing.T) {
+	store := newFakeStore(t)
+	settings := templateSettings(store, map[string]interface{}{"type": "none"}, nil)
+
+	var tmpl map[string]interface{}
+	cfg := settings.ProtocolSettings.(*Config)
+	if err := json.Unmarshal([]byte(cfg.Template), &tmpl); err != nil {
+		t.Fatalf("unmarshal: %v", err)
+	}
+	tmpl["concurrency"] = 4
+	raw, _ := json.Marshal(tmpl)
+	cfg.Template = string(raw)
+
+	storage, err := newTemplateStorage(settings, cfg)
+	if err != nil {
+		t.Fatalf("newTemplateStorage: %v", err)
+	}
+	if cap(storage.inflight) != 4 {
+		t.Fatalf("inflight cap is %d, want 4 from the template", cap(storage.inflight))
+	}
+}
+
+func TestTemplateConcurrencyDefault(t *testing.T) {
+	store := newFakeStore(t)
+	storage := newTemplateBackend(t, store, map[string]interface{}{"type": "none"}, nil)
+	if cap(storage.inflight) != driveMaxInflight {
+		t.Fatalf("default inflight cap is %d, want %d", cap(storage.inflight), driveMaxInflight)
+	}
+}

transport/internet/xdrive/wal.go

@@ -0,0 +1,445 @@
+package xdrive
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/xtls/xray-core/common/errors"
+)
+
+const (
+	maxCoalescedTicks = 8
+
+	segSuffix = ".seg"
+	endSuffix = ".end"
+	errSuffix = ".err"
+)
+
+func objectName(prefix string, seq int64, suffix string) string {
+	return fmt.Sprintf("%s/%09d%s", prefix, seq, suffix)
+}
+
+func parseEntry(name string) (int64, bool) {
+	dot := strings.LastIndexByte(name, '.')
+	if dot < 0 {
+		return 0, false
+	}
+	switch name[dot:] {
+	case segSuffix, endSuffix, errSuffix:
+	default:
+		return 0, false
+	}
+	seq, err := strconv.ParseInt(name[:dot], 10, 64)
+	if err != nil || seq < 0 {
+		return 0, false
+	}
+	return seq, true
+}
+
+type walWriter struct {
+	ctx     context.Context
+	storage Storage
+	prefix  string
+	params
+	sem chan struct{}
+	wg  sync.WaitGroup
+
+	mu       sync.Mutex
+	buf      []byte
+	seq      int64
+	lastSize int
+	held     int
+	closed   bool
+	err      error
+}
+
+func newWALWriter(ctx context.Context, storage Storage, prefix string, p params) *walWriter {
+	w := &walWriter{
+		ctx:     ctx,
+		storage: storage,
+		prefix:  prefix,
+		params:  p,
+		sem:     make(chan struct{}, p.concurrency),
+	}
+	go w.flushLoop()
+	return w
+}
+
+func (w *walWriter) 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.segmentBytes {
+		if err := w.flushLocked(); err != nil {
+			return 0, err
+		}
+	}
+	return len(p), nil
+}
+
+func (w *walWriter) 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 *walWriter) 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
+}
+
+func (w *walWriter) flushLocked() error {
+	if len(w.buf) == 0 {
+		return nil
+	}
+	if w.err != nil {
+		return w.err
+	}
+
+	n := len(w.buf)
+	if n > w.segmentBytes {
+		n = w.segmentBytes
+	}
+
+	chunk := make([]byte, n)
+	copy(chunk, w.buf[:n])
+	seq := w.seq
+	w.seq++
+
+	if n == len(w.buf) {
+		w.buf = w.buf[:0]
+	} else {
+		w.buf = append(w.buf[:0], w.buf[n:]...)
+	}
+	w.lastSize = len(w.buf)
+	w.held = 0
+
+	w.wg.Add(1)
+	go w.upload(seq, chunk)
+	return nil
+}
+
+func (w *walWriter) upload(seq int64, chunk []byte) {
+	defer w.wg.Done()
+
+	select {
+	case w.sem <- struct{}{}:
+	case <-w.ctx.Done():
+		return
+	}
+	defer func() { <-w.sem }()
+
+	if err := w.storage.Put(w.ctx, objectName(w.prefix, seq, segSuffix), chunk); err != nil {
+		w.mu.Lock()
+		if w.err == nil {
+			w.err = errors.New("failed to store segment").Base(err)
+		}
+		w.mu.Unlock()
+		w.storage.Put(w.ctx, objectName(w.prefix, seq, errSuffix), nil)
+	}
+}
+
+func (w *walWriter) Close() error {
+	w.mu.Lock()
+	if w.closed {
+		w.mu.Unlock()
+		return nil
+	}
+	w.closed = true
+	for len(w.buf) > 0 && w.err == nil {
+		w.flushLocked()
+	}
+	w.mu.Unlock()
+
+	w.wg.Wait()
+
+	w.mu.Lock()
+	err, seq := w.err, w.seq
+	w.mu.Unlock()
+
+	if err != nil {
+		return err
+	}
+	return w.storage.Put(w.ctx, objectName(w.prefix, seq, endSuffix), nil)
+}
+
+type walReader struct {
+	ctx     context.Context
+	storage Storage
+	prefix  string
+	params
+	seq int64
+
+	ch        chan []byte
+	discards  chan string
+	wake      chan struct{}
+	holeSince time.Time
+
+	errMu sync.Mutex
+	err   error
+}
+
+func newWALReader(ctx context.Context, storage Storage, prefix string, p params) *walReader {
+	r := &walReader{
+		ctx:      ctx,
+		storage:  storage,
+		prefix:   prefix,
+		params:   p,
+		ch:       make(chan []byte, p.concurrency),
+		discards: make(chan string, 4*p.concurrency),
+		wake:     make(chan struct{}, 1),
+	}
+	go r.run()
+	go r.discardLoop()
+	return r
+}
+
+func (r *walReader) Wake() {
+	select {
+	case r.wake <- struct{}{}:
+	default:
+	}
+}
+
+func (r *walReader) run() {
+	defer close(r.ch)
+
+	delay := r.minPollInterval
+	active := time.Now()
+	for {
+		polled := time.Now()
+		advanced, eof, err := r.poll()
+		if err != nil {
+			r.setErr(err)
+			return
+		}
+		if eof {
+			return
+		}
+
+		switch {
+		case advanced:
+			active = time.Now()
+			delay = r.minPollInterval
+		case time.Since(active) < r.eagerWindow:
+			delay = r.minPollInterval
+		default:
+			delay *= 2
+			if delay > r.maxPollInterval {
+				delay = r.maxPollInterval
+			}
+		}
+
+		timer := time.NewTimer(delay)
+		select {
+		case <-r.ctx.Done():
+			timer.Stop()
+			return
+		case <-timer.C:
+		case <-r.wake:
+			timer.Stop()
+			active = time.Now()
+			delay = r.minPollInterval
+			if rest := r.minPollInterval - time.Since(polled); rest > 0 {
+				select {
+				case <-r.ctx.Done():
+					return
+				case <-time.After(rest):
+				}
+			}
+		}
+	}
+}
+
+func (r *walReader) poll() (advanced, eof bool, err error) {
+	listed, err := r.storage.List(r.ctx, r.prefix)
+	if err != nil {
+		return false, false, err
+	}
+	if len(listed) == 0 {
+		return false, false, nil
+	}
+
+	pending := make(map[int64]Entry, len(listed))
+	ahead := false
+	for _, entry := range listed {
+		seq, ok := parseEntry(entry.Name)
+		if !ok {
+			continue
+		}
+		pending[seq] = entry
+		if seq > r.seq {
+			ahead = true
+		}
+	}
+
+	if _, ok := pending[r.seq]; !ok && ahead {
+		if r.holeSince.IsZero() {
+			r.holeSince = time.Now()
+		} else if time.Since(r.holeSince) >= r.holeTimeout {
+			return false, false, errors.New("segment ", r.seq,
+				" never arrived while later ones did, the peer lost it")
+		}
+	} else {
+		r.holeSince = time.Time{}
+	}
+
+	for {
+		if entry, ok := pending[r.seq]; ok && strings.HasSuffix(entry.Name, errSuffix) {
+			r.discard(r.prefix + "/" + entry.Name)
+			return advanced, false, errors.New("the peer could not store segment ", r.seq)
+		}
+
+		batch, done := r.nextBatch(pending)
+		if done {
+			return advanced, true, nil
+		}
+		if len(batch) == 0 {
+			return advanced, false, nil
+		}
+
+		chunks, err := r.fetch(batch)
+		if err != nil {
+			if err == errNotFound {
+				return advanced, false, nil
+			}
+			return advanced, false, err
+		}
+
+		for i, chunk := range chunks {
+			select {
+			case r.ch <- chunk:
+			case <-r.ctx.Done():
+				return advanced, true, nil
+			}
+			r.seq++
+			advanced = true
+			r.discard(r.prefix + "/" + batch[i].Name)
+		}
+	}
+}
+
+func (r *walReader) nextBatch(pending map[int64]Entry) (batch []Entry, done bool) {
+	for i := 0; i < r.concurrency; i++ {
+		entry, ok := pending[r.seq+int64(i)]
+		if !ok {
+			break
+		}
+		if !strings.HasSuffix(entry.Name, segSuffix) {
+			if i == 0 && strings.HasSuffix(entry.Name, endSuffix) {
+				r.discard(r.prefix + "/" + entry.Name)
+				return nil, true
+			}
+			break
+		}
+		batch = append(batch, entry)
+	}
+	return batch, false
+}
+
+func (r *walReader) fetch(batch []Entry) ([][]byte, error) {
+	chunks := make([][]byte, len(batch))
+	failures := make([]error, len(batch))
+
+	var wg sync.WaitGroup
+	for i, entry := range batch {
+		if entry.Inline != nil {
+			chunks[i] = entry.Inline
+			continue
+		}
+		wg.Add(1)
+		go func(i int, name string) {
+			defer wg.Done()
+			chunks[i], failures[i] = r.storage.Get(r.ctx, r.prefix+"/"+name)
+		}(i, entry.Name)
+	}
+	wg.Wait()
+
+	for i := range batch {
+		if failures[i] != nil {
+			return nil, failures[i]
+		}
+	}
+	return chunks, nil
+}
+
+func (r *walReader) discard(name string) {
+	select {
+	case r.discards <- name:
+	default:
+	}
+}
+
+func (r *walReader) discardLoop() {
+	var wg sync.WaitGroup
+	defer wg.Wait()
+
+	sem := make(chan struct{}, r.concurrency)
+	for {
+		select {
+		case <-r.ctx.Done():
+			return
+		case name := <-r.discards:
+			sem <- struct{}{}
+			wg.Add(1)
+			go func(name string) {
+				defer wg.Done()
+				defer func() { <-sem }()
+				r.storage.Delete(r.ctx, name)
+			}(name)
+		}
+	}
+}
+
+func (r *walReader) setErr(err error) {
+	r.errMu.Lock()
+	defer r.errMu.Unlock()
+	if r.err == nil {
+		r.err = err
+	}
+}
+
+func (r *walReader) Err() error {
+	r.errMu.Lock()
+	defer r.errMu.Unlock()
+	if r.err != nil {
+		return r.err
+	}
+	return io.EOF
+}

transport/internet/xdrive/xdrive.go

@@ -0,0 +1,308 @@
+package xdrive
+
+import (
+	"context"
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/xtls/xray-core/common"
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/net"
+	"github.com/xtls/xray-core/transport/internet"
+	"github.com/xtls/xray-core/transport/internet/stat"
+)
+
+const (
+	protocolName = "xdrive"
+	sessionsDir  = "sessions"
+	streamsDir   = "streams"
+	uplinkDir    = "c2s"
+	downlinkDir  = "s2c"
+)
+
+func init() {
+	common.Must(internet.RegisterProtocolConfigCreator(protocolName, func() interface{} {
+		return new(Config)
+	}))
+	common.Must(internet.RegisterTransportDialer(protocolName, Dial))
+	common.Must(internet.RegisterTransportListener(protocolName, Serve))
+}
+
+func newSessionID() (string, error) {
+	buf := make([]byte, 16)
+	if _, err := rand.Read(buf); err != nil {
+		return "", errors.New("failed to generate session id").Base(err)
+	}
+	return hex.EncodeToString(buf), nil
+}
+
+func announceName(session string, at time.Time) string {
+	return fmt.Sprintf("%s/%d-%s", sessionsDir, at.UnixNano(), session)
+}
+
+func parseAnnounce(entry string) (string, time.Time, bool) {
+	dash := strings.IndexByte(entry, '-')
+	if dash <= 0 || dash == len(entry)-1 {
+		return "", time.Time{}, false
+	}
+	nanos, err := strconv.ParseInt(entry[:dash], 10, 64)
+	if err != nil {
+		return "", time.Time{}, false
+	}
+	return entry[dash+1:], time.Unix(0, nanos), true
+}
+
+func sessionPrefix(session string) string {
+	return streamsDir + "/" + session
+}
+
+func uplinkPrefix(session string) string {
+	return sessionPrefix(session) + "/" + uplinkDir
+}
+
+func downlinkPrefix(session string) string {
+	return sessionPrefix(session) + "/" + downlinkDir
+}
+
+func streamConfig(streamSettings *internet.MemoryStreamConfig) (*Config, error) {
+	config, ok := streamSettings.ProtocolSettings.(*Config)
+	if !ok || config == nil {
+		return nil, errors.New("invalid protocol settings")
+	}
+	return config, nil
+}
+
+func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (stat.Connection, error) {
+	config, err := streamConfig(streamSettings)
+	if err != nil {
+		return nil, err
+	}
+
+	storage, err := newStorage(streamSettings)
+	if err != nil {
+		return nil, err
+	}
+
+	session, err := newSessionID()
+	if err != nil {
+		storage.Close()
+		return nil, err
+	}
+
+	if err := storage.Put(ctx, announceName(session, time.Now()), nil); err != nil {
+		storage.Close()
+		return nil, errors.New("failed to announce session ", session).Base(err)
+	}
+
+	errors.LogInfo(ctx, "opened session ", session)
+
+	return newConn(context.Background(), storage,
+		uplinkPrefix(session), downlinkPrefix(session), paramsFromConfig(config), func() {
+			storage.Close()
+		}), nil
+}
+
+type Listener struct {
+	ctx     context.Context
+	cancel  context.CancelFunc
+	storage Storage
+	addConn internet.ConnHandler
+	params
+
+	mu        sync.Mutex
+	active    map[string]bool
+	handled   map[string]time.Time
+	idleSince map[string]time.Time
+}
+
+func Serve(ctx context.Context, address net.Address, port net.Port, streamSettings *internet.MemoryStreamConfig, addConn internet.ConnHandler) (internet.Listener, error) {
+	config, err := streamConfig(streamSettings)
+	if err != nil {
+		return nil, err
+	}
+
+	storage, err := newStorage(streamSettings)
+	if err != nil {
+		return nil, err
+	}
+
+	listenerCtx, cancel := context.WithCancel(context.Background())
+	listener := &Listener{
+		ctx:       listenerCtx,
+		cancel:    cancel,
+		storage:   storage,
+		addConn:   addConn,
+		params:    paramsFromConfig(config),
+		active:    make(map[string]bool),
+		handled:   make(map[string]time.Time),
+		idleSince: make(map[string]time.Time),
+	}
+
+	go listener.acceptLoop(ctx)
+	go listener.collectLoop(ctx)
+
+	return listener, nil
+}
+
+func (l *Listener) acceptLoop(logCtx context.Context) {
+	delay := l.minPollInterval
+	active := time.Now()
+	for {
+		accepted, err := l.acceptPending(logCtx)
+		if err != nil {
+			errors.LogWarningInner(logCtx, err, "failed to list sessions")
+		}
+
+		switch {
+		case accepted:
+			active = time.Now()
+			delay = l.minPollInterval
+		case time.Since(active) < l.eagerWindow:
+			delay = l.minPollInterval
+		default:
+			delay *= 2
+			if delay > l.maxPollInterval {
+				delay = l.maxPollInterval
+			}
+		}
+
+		select {
+		case <-l.ctx.Done():
+			return
+		case <-time.After(delay):
+		}
+	}
+}
+
+func (l *Listener) acceptPending(logCtx context.Context) (bool, error) {
+	sessions, err := l.storage.List(l.ctx, sessionsDir)
+	if err != nil {
+		return false, err
+	}
+
+	accepted := false
+	for _, listed := range sessions {
+		entry := listed.Name
+		full := sessionsDir + "/" + entry
+
+		session, at, ok := parseAnnounce(entry)
+		if !ok {
+			go l.drop(full)
+			continue
+		}
+		if time.Since(at) > l.sessionTTL {
+			errors.LogInfo(logCtx, "dropping the stale announcement of session ", session)
+			go l.drop(full)
+			go l.drop(sessionPrefix(session))
+			continue
+		}
+		if !l.claim(session) {
+			continue
+		}
+		go l.drop(full)
+		errors.LogInfo(logCtx, "accepted session ", session)
+		accepted = true
+		l.addConn(l.newSessionConn(session))
+	}
+	return accepted, nil
+}
+
+func (l *Listener) drop(name string) {
+	l.storage.Delete(l.ctx, name)
+}
+
+func (l *Listener) claim(session string) bool {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if l.active[session] || !l.handled[session].IsZero() {
+		return false
+	}
+	l.active[session] = true
+	l.handled[session] = time.Now()
+	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()
+		})
+}
+
+func (l *Listener) collectLoop(logCtx context.Context) {
+	interval := l.sessionTTL / 2
+	for {
+		select {
+		case <-l.ctx.Done():
+			return
+		case <-time.After(interval):
+		}
+		if err := l.collect(); err != nil {
+			errors.LogWarningInner(logCtx, err, "failed to collect abandoned sessions")
+		}
+	}
+}
+
+func (l *Listener) collect() error {
+	sessions, err := l.storage.List(l.ctx, streamsDir)
+	if err != nil {
+		return err
+	}
+
+	now := time.Now()
+	var expired []string
+
+	l.mu.Lock()
+	present := make(map[string]bool, len(sessions))
+	for _, listed := range sessions {
+		session := listed.Name
+		present[session] = true
+		if l.active[session] {
+			delete(l.idleSince, session)
+			continue
+		}
+		since, seen := l.idleSince[session]
+		if !seen {
+			l.idleSince[session] = now
+			continue
+		}
+		if now.Sub(since) >= l.sessionTTL {
+			expired = append(expired, session)
+			delete(l.idleSince, session)
+		}
+	}
+	for session := range l.idleSince {
+		if !present[session] {
+			delete(l.idleSince, session)
+		}
+	}
+	for session, at := range l.handled {
+		if !l.active[session] && now.Sub(at) >= l.sessionTTL {
+			delete(l.handled, session)
+		}
+	}
+	l.mu.Unlock()
+
+	for _, session := range expired {
+		if err := l.storage.Delete(l.ctx, sessionPrefix(session)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (l *Listener) Addr() net.Addr {
+	return placeholderAddr
+}
+
+func (l *Listener) Close() error {
+	l.cancel()
+	return l.storage.Close()
+}

transport/internet/xdrive/xdrive_test.go

@@ -0,0 +1,583 @@
+package xdrive
+
+import (
+	"bytes"
+	"context"
+	"crypto/rand"
+	"io"
+	"os"
+	"strings"
+	"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/stat"
+)
+
+const testPatience = 30 * time.Second
+
+func settings(folder string) *internet.MemoryStreamConfig {
+	return &internet.MemoryStreamConfig{
+		ProtocolName: protocolName,
+		ProtocolSettings: &Config{
+			RemoteFolder:      folder,
+			Service:           "local",
+			FlushIntervalMs:   5,
+			PollIntervalMs:    5,
+			MaxPollIntervalMs: 20,
+			SessionTtlSeconds: 5,
+		},
+	}
+}
+
+func pair(t *testing.T) (client, server stat.Connection, cleanup func()) {
+	t.Helper()
+	return pairWith(t, settings(t.TempDir()))
+}
+
+func pairWith(t *testing.T, streamSettings *internet.MemoryStreamConfig) (client, server stat.Connection, cleanup func()) {
+	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)
+	}
+
+	client, err = Dial(context.Background(), net.Destination{}, streamSettings)
+	if err != nil {
+		listener.Close()
+		t.Fatalf("Dial: %v", err)
+	}
+
+	select {
+	case server = <-accepted:
+	case <-time.After(testPatience):
+		client.Close()
+		listener.Close()
+		t.Fatal("listener did not accept the session")
+	}
+
+	return client, server, func() {
+		client.Close()
+		server.Close()
+		listener.Close()
+	}
+}
+
+func expectRead(t *testing.T, conn stat.Connection, want string) {
+	t.Helper()
+
+	if err := conn.SetReadDeadline(time.Now().Add(testPatience)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	buf := make([]byte, len(want))
+	if _, err := io.ReadFull(conn, buf); err != nil {
+		t.Fatalf("ReadFull: %v", err)
+	}
+	if string(buf) != want {
+		t.Fatalf("read %q, want %q", buf, want)
+	}
+}
+
+func TestRoundTrip(t *testing.T) {
+	client, server, cleanup := pair(t)
+	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")
+}
+
+func TestInterleaved(t *testing.T) {
+	client, server, cleanup := pair(t)
+	defer cleanup()
+
+	for i := 0; i < 20; i++ {
+		if _, err := client.Write([]byte("up")); err != nil {
+			t.Fatalf("client write %d: %v", i, err)
+		}
+		expectRead(t, server, "up")
+
+		if _, err := server.Write([]byte("down")); err != nil {
+			t.Fatalf("server write %d: %v", i, err)
+		}
+		expectRead(t, client, "down")
+	}
+}
+
+func TestMultiSegmentTransfer(t *testing.T) {
+	client, server, cleanup := pair(t)
+	defer cleanup()
+
+	payload := make([]byte, 3*defaultSegmentBytes+1234)
+	if _, err := rand.Read(payload); err != nil {
+		t.Fatalf("rand: %v", err)
+	}
+
+	go func() {
+		client.Write(payload)
+	}()
+
+	if err := server.SetReadDeadline(time.Now().Add(30 * time.Second)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	got := make([]byte, len(payload))
+	if _, err := io.ReadFull(server, got); err != nil {
+		t.Fatalf("ReadFull: %v", err)
+	}
+	if !bytes.Equal(got, payload) {
+		t.Fatal("payload mismatch")
+	}
+}
+
+func TestCloseEOF(t *testing.T) {
+	client, server, cleanup := pair(t)
+	defer cleanup()
+
+	if _, err := client.Write([]byte("bye")); err != nil {
+		t.Fatalf("client write: %v", err)
+	}
+	if err := client.Close(); err != nil {
+		t.Fatalf("client close: %v", err)
+	}
+
+	if err := server.SetReadDeadline(time.Now().Add(5 * time.Second)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	got, err := io.ReadAll(server)
+	if err != nil {
+		t.Fatalf("ReadAll: %v", err)
+	}
+	if string(got) != "bye" {
+		t.Fatalf("read %q, want %q", got, "bye")
+	}
+}
+
+func TestReadDeadline(t *testing.T) {
+	client, _, cleanup := pair(t)
+	defer cleanup()
+
+	if err := client.SetReadDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	buf := make([]byte, 4)
+	if _, err := client.Read(buf); !os.IsTimeout(err) {
+		t.Fatalf("Read returned %v, want a timeout", err)
+	}
+}
+
+func TestLocalNameEscape(t *testing.T) {
+	root := t.TempDir()
+	storage, err := newLocalStorage(root)
+	if err != nil {
+		t.Fatalf("newLocalStorage: %v", err)
+	}
+
+	if err := storage.Put(context.Background(), "../escaped", []byte("x")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+	if _, err := os.Stat(root + "/escaped"); err != nil {
+		t.Fatalf("name was not clamped inside the root: %v", err)
+	}
+}
+
+func TestLocalMissingObject(t *testing.T) {
+	storage, err := newLocalStorage(t.TempDir())
+	if err != nil {
+		t.Fatalf("newLocalStorage: %v", err)
+	}
+
+	if _, err := storage.Get(context.Background(), "nothing/here"); err != errNotFound {
+		t.Fatalf("Get returned %v, want errNotFound", err)
+	}
+	names, err := storage.List(context.Background(), "nothing")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(names) != 0 {
+		t.Fatalf("List returned %v, want none", names)
+	}
+}
+
+func TestResumeAfterIdle(t *testing.T) {
+	client, server, cleanup := pair(t)
+	defer cleanup()
+
+	if _, err := client.Write([]byte("first")); err != nil {
+		t.Fatalf("client write: %v", err)
+	}
+	expectRead(t, server, "first")
+
+	time.Sleep(200 * time.Millisecond)
+
+	if _, err := client.Write([]byte("second")); err != nil {
+		t.Fatalf("client write: %v", err)
+	}
+	expectRead(t, server, "second")
+}
+
+func TestParseEntry(t *testing.T) {
+	cases := []struct {
+		name string
+		seq  int64
+		ok   bool
+	}{
+		{"000000000.seg", 0, true},
+		{"000000042.seg", 42, true},
+		{"000000007.end", 7, true},
+		{"000000001.tmp", 0, false},
+		{"notanumber.seg", 0, false},
+		{"000000001", 0, false},
+	}
+	for _, c := range cases {
+		seq, ok := parseEntry(c.name)
+		if ok != c.ok || (ok && seq != c.seq) {
+			t.Fatalf("parseEntry(%q) = %d, %v; want %d, %v", c.name, seq, ok, c.seq, c.ok)
+		}
+	}
+}
+
+func TestParamDefaults(t *testing.T) {
+	p := paramsFromConfig(&Config{})
+	if p.segmentBytes != defaultSegmentBytes || p.flushInterval != defaultFlushInterval {
+		t.Fatalf("defaults not applied: %+v", p)
+	}
+
+	p = paramsFromConfig(&Config{SegmentBytes: 1 << 30, PollIntervalMs: 400, MaxPollIntervalMs: 100})
+	if p.segmentBytes != maxSegmentBytes {
+		t.Fatalf("segmentBytes is %d, want %d", p.segmentBytes, maxSegmentBytes)
+	}
+	if p.maxPollInterval < p.minPollInterval {
+		t.Fatalf("maxPollInterval %v below minPollInterval %v", p.maxPollInterval, p.minPollInterval)
+	}
+}
+
+func waitFor(t *testing.T, what string, done func() bool) {
+	t.Helper()
+
+	deadline := time.Now().Add(5 * time.Second)
+	for time.Now().Before(deadline) {
+		if done() {
+			return
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
+	t.Fatalf("timed out waiting for %s", what)
+}
+
+func newTestListener(t *testing.T, folder string) *Listener {
+	t.Helper()
+
+	storage, err := newLocalStorage(folder)
+	if err != nil {
+		t.Fatalf("newLocalStorage: %v", err)
+	}
+	return &Listener{
+		ctx:       context.Background(),
+		storage:   storage,
+		params:    paramsFromConfig(&Config{SessionTtlSeconds: 1}),
+		active:    make(map[string]bool),
+		handled:   make(map[string]time.Time),
+		idleSince: make(map[string]time.Time),
+	}
+}
+
+func TestCollectAbandoned(t *testing.T) {
+	folder := t.TempDir()
+	listener := newTestListener(t, folder)
+
+	if err := listener.storage.Put(context.Background(), uplinkPrefix("dead")+"/000000000.seg", []byte("x")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	if err := listener.collect(); err != nil {
+		t.Fatalf("collect: %v", err)
+	}
+	names, _ := listener.storage.List(context.Background(), streamsDir)
+	if len(names) != 1 {
+		t.Fatalf("first pass removed the session, got %v", names)
+	}
+
+	listener.idleSince["dead"] = time.Now().Add(-2 * time.Second)
+	if err := listener.collect(); err != nil {
+		t.Fatalf("collect: %v", err)
+	}
+	names, _ = listener.storage.List(context.Background(), streamsDir)
+	if len(names) != 0 {
+		t.Fatalf("abandoned session still there, got %v", names)
+	}
+}
+
+func TestCollectKeepsActive(t *testing.T) {
+	folder := t.TempDir()
+	listener := newTestListener(t, folder)
+	listener.active["live"] = true
+
+	if err := listener.storage.Put(context.Background(), uplinkPrefix("live")+"/000000000.seg", []byte("x")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	listener.idleSince["live"] = time.Now().Add(-2 * time.Second)
+	if err := listener.collect(); err != nil {
+		t.Fatalf("collect: %v", err)
+	}
+	names, _ := listener.storage.List(context.Background(), streamsDir)
+	if len(names) != 1 {
+		t.Fatalf("collected an active session, got %v", names)
+	}
+}
+
+func TestParseAnnounce(t *testing.T) {
+	session, at, ok := parseAnnounce("1757000000123456789-abc123")
+	if !ok || session != "abc123" || at.UnixNano() != 1757000000123456789 {
+		t.Fatalf("parseAnnounce returned %q, %v, %v", session, at.UnixNano(), ok)
+	}
+	for _, bad := range []string{"abc123", "-abc123", "1757000000-", "notanumber-abc"} {
+		if _, _, ok := parseAnnounce(bad); ok {
+			t.Fatalf("parseAnnounce accepted %q", bad)
+		}
+	}
+}
+
+func TestStaleAnnounce(t *testing.T) {
+	folder := t.TempDir()
+	listener := newTestListener(t, folder)
+
+	ctx := context.Background()
+	stale := announceName("ghost", time.Now().Add(-time.Hour))
+	if err := listener.storage.Put(ctx, stale, nil); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+	if err := listener.storage.Put(ctx, uplinkPrefix("ghost")+"/000000000.seg", []byte("x")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	accepted, err := listener.acceptPending(ctx)
+	if err != nil {
+		t.Fatalf("acceptPending: %v", err)
+	}
+	if accepted {
+		t.Fatal("accepted a stale announcement")
+	}
+
+	waitFor(t, "the stale announcement to be removed", func() bool {
+		names, _ := listener.storage.List(ctx, sessionsDir)
+		return len(names) == 0
+	})
+	waitFor(t, "the stale session data to be removed", func() bool {
+		names, _ := listener.storage.List(ctx, streamsDir)
+		return len(names) == 0
+	})
+}
+
+func TestFreshAnnounce(t *testing.T) {
+	folder := t.TempDir()
+	listener := newTestListener(t, folder)
+	listener.addConn = func(conn stat.Connection) { conn.Close() }
+
+	ctx := context.Background()
+	if err := listener.storage.Put(ctx, announceName("fresh", time.Now()), nil); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	accepted, err := listener.acceptPending(ctx)
+	if err != nil {
+		t.Fatalf("acceptPending: %v", err)
+	}
+	if !accepted {
+		t.Fatal("did not accept a fresh announcement")
+	}
+}
+
+func TestAnnouncePrecision(t *testing.T) {
+	at := time.Unix(1757000000, int64(900*time.Millisecond))
+	entry := strings.TrimPrefix(announceName("abc123", at), sessionsDir+"/")
+
+	session, parsed, ok := parseAnnounce(entry)
+	if !ok || session != "abc123" {
+		t.Fatalf("parseAnnounce(%q) returned %q, %v", entry, session, ok)
+	}
+	if !parsed.Equal(at) {
+		t.Fatalf("timestamp came back as %v, want %v", parsed, at)
+	}
+}
+
+func TestRecentAnnounceTTL(t *testing.T) {
+	folder := t.TempDir()
+	listener := newTestListener(t, folder)
+	listener.addConn = func(conn stat.Connection) { conn.Close() }
+
+	ctx := context.Background()
+	recent := time.Now().Add(-900 * time.Millisecond)
+	if err := listener.storage.Put(ctx, announceName("recent", recent), nil); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	accepted, err := listener.acceptPending(ctx)
+	if err != nil {
+		t.Fatalf("acceptPending: %v", err)
+	}
+	if !accepted {
+		t.Fatal("dropped an announcement younger than the TTL")
+	}
+}
+
+func TestMissingSegment(t *testing.T) {
+	storage, err := newLocalStorage(t.TempDir())
+	if err != nil {
+		t.Fatalf("newLocalStorage: %v", err)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	p := paramsFromConfig(&Config{PollIntervalMs: 5, MaxPollIntervalMs: 20, HoleTimeoutMs: 200})
+	if err := storage.Put(ctx, objectName("hole", 1, segSuffix), []byte("second")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	reader := newWALReader(ctx, storage, "hole", p)
+	select {
+	case _, ok := <-reader.ch:
+		if ok {
+			t.Fatal("delivered data past a missing segment")
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("reader did not give up on a missing segment")
+	}
+
+	err = reader.Err()
+	if err == nil || err == io.EOF {
+		t.Fatalf("Err returned %v, want a failure", err)
+	}
+}
+
+func TestIdleStreamWaits(t *testing.T) {
+	storage, err := newLocalStorage(t.TempDir())
+	if err != nil {
+		t.Fatalf("newLocalStorage: %v", err)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	p := paramsFromConfig(&Config{PollIntervalMs: 5, MaxPollIntervalMs: 20, HoleTimeoutMs: 100})
+	reader := newWALReader(ctx, storage, "idle", p)
+
+	time.Sleep(400 * time.Millisecond)
+	if err := storage.Put(ctx, objectName("idle", 0, segSuffix), []byte("late")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	select {
+	case data, ok := <-reader.ch:
+		if !ok {
+			t.Fatalf("the reader gave up on an idle stream: %v", reader.Err())
+		}
+		if string(data) != "late" {
+			t.Fatalf("read %q, want %q", data, "late")
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("reader missed a late segment")
+	}
+}
+
+func TestFailureMarker(t *testing.T) {
+	storage, err := newLocalStorage(t.TempDir())
+	if err != nil {
+		t.Fatalf("newLocalStorage: %v", err)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	p := paramsFromConfig(&Config{PollIntervalMs: 5, MaxPollIntervalMs: 20})
+	if err := storage.Put(ctx, objectName("broken", 0, segSuffix), []byte("first")); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+	if err := storage.Put(ctx, objectName("broken", 1, errSuffix), nil); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	reader := newWALReader(ctx, storage, "broken", p)
+
+	select {
+	case data, ok := <-reader.ch:
+		if !ok || string(data) != "first" {
+			t.Fatalf("want the segment before the marker, got %q %v", data, ok)
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("reader did not deliver the first segment")
+	}
+
+	select {
+	case _, ok := <-reader.ch:
+		if ok {
+			t.Fatal("delivered data past the failure marker")
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("reader did not stop on the failure marker")
+	}
+
+	if err := reader.Err(); err == nil || err == io.EOF {
+		t.Fatalf("Err returned %v, want a failure", err)
+	}
+}
+
+type inlineOnlyStorage struct {
+	Storage
+	gets int64
+}
+
+func (s *inlineOnlyStorage) List(ctx context.Context, prefix string) ([]Entry, error) {
+	return []Entry{{Name: "000000000" + segSuffix, Inline: []byte("carried by the listing")}}, nil
+}
+
+func (s *inlineOnlyStorage) Get(ctx context.Context, name string) ([]byte, error) {
+	atomic.AddInt64(&s.gets, 1)
+	return nil, errNotFound
+}
+
+func (s *inlineOnlyStorage) Delete(ctx context.Context, name string) error {
+	return nil
+}
+
+func TestInlinePayload(t *testing.T) {
+	base, err := newLocalStorage(t.TempDir())
+	if err != nil {
+		t.Fatalf("newLocalStorage: %v", err)
+	}
+	storage := &inlineOnlyStorage{Storage: base}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	reader := newWALReader(ctx, storage, "inline", paramsFromConfig(&Config{PollIntervalMs: 5}))
+	select {
+	case data, ok := <-reader.ch:
+		if !ok {
+			t.Fatalf("reader stopped: %v", reader.Err())
+		}
+		if string(data) != "carried by the listing" {
+			t.Fatalf("read %q, want the inline payload", data)
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("reader did not deliver the inline payload")
+	}
+
+	if got := atomic.LoadInt64(&storage.gets); got != 0 {
+		t.Fatalf("called Get %d times for an inline payload", got)
+	}
+}

transport/internet/xdrive/yandex_live_test.go

@@ -0,0 +1,171 @@
+package xdrive
+
+import (
+	"bytes"
+	"context"
+	"crypto/rand"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/xtls/xray-core/transport/internet"
+)
+
+const yandexBase = "https://webdav.yandex.ru"
+
+func envUint(name string, def uint32) uint32 {
+	if v := os.Getenv(name); v != "" {
+		var n uint32
+		fmt.Sscanf(v, "%d", &n)
+		if n > 0 {
+			return n
+		}
+	}
+	return def
+}
+
+func liveYandexSettings(t *testing.T) (*internet.MemoryStreamConfig, string, func()) {
+	t.Helper()
+
+	user := os.Getenv("XDRIVE_YANDEX_USER")
+	pass := os.Getenv("XDRIVE_YANDEX_PASS")
+	if user == "" || pass == "" {
+		t.Skip("set XDRIVE_YANDEX_USER and XDRIVE_YANDEX_PASS to run this test")
+	}
+
+	folder := fmt.Sprintf("xdrive-live-%d", time.Now().UnixNano())
+	dav := func(method, path string) int {
+		req, _ := http.NewRequest(method, yandexBase+path, nil)
+		req.SetBasicAuth(user, pass)
+		resp, err := http.DefaultClient.Do(req)
+		if err != nil {
+			t.Fatalf("%s %s: %v", method, path, err)
+		}
+		resp.Body.Close()
+		return resp.StatusCode
+	}
+	if code := dav("MKCOL", "/"+folder); code != 201 && code != 405 {
+		t.Fatalf("MKCOL answered %d", code)
+	}
+
+	tmpl := map[string]interface{}{
+		"flatten": true,
+		"auth":    map[string]interface{}{"type": "basic", "username": "{secret0}", "password": "{secret1}"},
+		"put":     map[string]interface{}{"method": "PUT", "url": yandexBase + "/{folder}/{name}"},
+		"get":     map[string]interface{}{"method": "GET", "url": yandexBase + "/{folder}/{name}"},
+		"delete":  map[string]interface{}{"method": "DELETE", "url": yandexBase + "/{folder}/{name}"},
+		"list": map[string]interface{}{
+			"method": "PROPFIND", "url": yandexBase + "/{folder}/",
+			"headers": map[string]interface{}{"Depth": "1"}, "namesRegex": `<d:href>[^<]*/([^/<]+)</d:href>`,
+		},
+		"retry": map[string]interface{}{"status": []int{429, 500, 502, 503}},
+	}
+	raw, _ := json.Marshal(tmpl)
+	settings := &internet.MemoryStreamConfig{
+		ProtocolName: protocolName,
+		ProtocolSettings: &Config{
+			RemoteFolder:      folder,
+			Service:           "template",
+			Secrets:           []string{user, pass},
+			Template:          string(raw),
+			SegmentBytes:      262144,
+			FlushIntervalMs:   100,
+			PollIntervalMs:    300,
+			MaxPollIntervalMs: 1500,
+			SessionTtlSeconds: 120,
+			Concurrency:       envUint("XDRIVE_LIVE_CONCURRENCY", 8),
+		},
+	}
+	cleanup := func() { dav("DELETE", "/"+folder) }
+	return settings, folder, cleanup
+}
+
+func TestLiveYandexStorage(t *testing.T) {
+	settings, _, cleanup := liveYandexSettings(t)
+	defer cleanup()
+
+	storage, err := newTemplateStorage(settings, settings.ProtocolSettings.(*Config))
+	if err != nil {
+		t.Fatalf("newTemplateStorage: %v", err)
+	}
+	ctx := context.Background()
+
+	name := "streams/live/c2s/000000000.seg"
+	payload := []byte("xdrive over real yandex webdav")
+
+	start := time.Now()
+	if err := storage.Put(ctx, name, payload); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+	t.Logf("Put took %v", time.Since(start))
+
+	start = time.Now()
+	names, err := storage.List(ctx, "streams/live/c2s")
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	t.Logf("List took %v", time.Since(start))
+	if len(names) != 1 || names[0].Name != "000000000.seg" {
+		t.Fatalf("List returned %v, want one segment", names)
+	}
+
+	start = time.Now()
+	got, err := storage.Get(ctx, name)
+	if err != nil {
+		t.Fatalf("Get: %v", err)
+	}
+	t.Logf("Get took %v", time.Since(start))
+	if !bytes.Equal(got, payload) {
+		t.Fatalf("Get returned %q", got)
+	}
+
+	if _, err := storage.Get(ctx, "streams/live/c2s/000000009.seg"); err != errNotFound {
+		t.Fatalf("Get of a missing object returned %v, want errNotFound", err)
+	}
+
+	if err := storage.Delete(ctx, name); err != nil {
+		t.Fatalf("Delete: %v", err)
+	}
+}
+
+func TestLiveYandexTransport(t *testing.T) {
+	settings, _, cleanup := liveYandexSettings(t)
+	defer cleanup()
+
+	client, server, done := pairWith(t, settings)
+	defer done()
+
+	start := time.Now()
+	if _, err := client.Write([]byte("ping")); err != nil {
+		t.Fatalf("client write: %v", err)
+	}
+	expectRead(t, server, "ping")
+	t.Logf("client to server round took %v", time.Since(start))
+
+	size := 1000000
+	if raw := os.Getenv("XDRIVE_LIVE_BYTES"); raw != "" {
+		fmt.Sscanf(raw, "%d", &size)
+	}
+	payload := make([]byte, size)
+	rand.Read(payload)
+
+	start = time.Now()
+	go func() { client.Write(payload) }()
+	if err := server.SetReadDeadline(time.Now().Add(5 * time.Minute)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	got := make([]byte, len(payload))
+	if _, err := io.ReadFull(server, got); err != nil {
+		t.Fatalf("ReadFull: %v", err)
+	}
+	elapsed := time.Since(start)
+	if !bytes.Equal(got, payload) {
+		t.Fatal("payload mismatch")
+	}
+	t.Logf("%d bytes in %v -> %.1f KiB/s", len(payload), elapsed,
+		float64(len(payload))/1024/elapsed.Seconds())
+}