feat: ignoreClientBandwidth

app/cmd/server.go

@@ -39,6 +39,7 @@ type serverConfig struct {
 	ACME                  *serverConfigACME           `mapstructure:"acme"`
 	QUIC                  serverConfigQUIC            `mapstructure:"quic"`
 	Bandwidth             serverConfigBandwidth       `mapstructure:"bandwidth"`
+	IgnoreClientBandwidth bool                        `mapstructure:"ignoreClientBandwidth"`
 	DisableUDP            bool                        `mapstructure:"disableUDP"`
 	UDPIdleTimeout        time.Duration               `mapstructure:"udpIdleTimeout"`
 	Auth                  serverConfigAuth            `mapstructure:"auth"`
@@ -360,6 +361,11 @@ func (c *serverConfig) fillBandwidthConfig(hyConfig *server.Config) error {
 	return nil
 }
 
+func (c *serverConfig) fillIgnoreClientBandwidth(hyConfig *server.Config) error {
+	hyConfig.IgnoreClientBandwidth = c.IgnoreClientBandwidth
+	return nil
+}
+
 func (c *serverConfig) fillDisableUDP(hyConfig *server.Config) error {
 	hyConfig.DisableUDP = c.DisableUDP
 	return nil
@@ -445,6 +451,7 @@ func (c *serverConfig) Config() (*server.Config, error) {
 		c.fillQUICConfig,
 		c.fillOutboundConfig,
 		c.fillBandwidthConfig,
+		c.fillIgnoreClientBandwidth,
 		c.fillDisableUDP,
 		c.fillUDPIdleTimeout,
 		c.fillAuthenticator,

app/cmd/server_test.go

@@ -55,6 +55,7 @@ func TestServerConfig(t *testing.T) {
 			Up:   "500 mbps",
 			Down: "100 mbps",
 		},
+		IgnoreClientBandwidth: true,
 		DisableUDP:            true,
 		UDPIdleTimeout:        120 * time.Second,
 		Auth: serverConfigAuth{

app/cmd/server_test.yaml

@@ -34,6 +34,8 @@ bandwidth:
   up: 500 mbps
   down: 100 mbps
 
+ignoreClientBandwidth: true
+
 disableUDP: true
 udpIdleTimeout: 120s
 

core/client/client.go

@@ -9,9 +9,7 @@ import (
 	"time"
 
 	coreErrs "github.com/apernet/hysteria/core/errors"
-	"github.com/apernet/hysteria/core/internal/congestion/bbr"
+	"github.com/apernet/hysteria/core/internal/congestion"
-	"github.com/apernet/hysteria/core/internal/congestion/brutal"
-	"github.com/apernet/hysteria/core/internal/congestion/common"
 	"github.com/apernet/hysteria/core/internal/protocol"
 	"github.com/apernet/hysteria/core/internal/utils"
 
@@ -104,7 +102,10 @@ func (c *clientImpl) connect() error {
 		},
 		Header: make(http.Header),
 	}
-	protocol.AuthRequestDataToHeader(req.Header, c.config.Auth, c.config.BandwidthConfig.MaxRx)
+	protocol.AuthRequestToHeader(req.Header, protocol.AuthRequest{
+		Auth: c.config.Auth,
+		Rx:   c.config.BandwidthConfig.MaxRx,
+	})
 	resp, err := rt.RoundTrip(req)
 	if err != nil {
 		if conn != nil {
@@ -119,28 +120,30 @@ func (c *clientImpl) connect() error {
 		return coreErrs.AuthError{StatusCode: resp.StatusCode}
 	}
 	// Auth OK
-	udpEnabled, serverRx := protocol.AuthResponseDataFromHeader(resp.Header)
+	authResp := protocol.AuthResponseFromHeader(resp.Header)
+	if authResp.RxAuto {
+		// Server asks client to use bandwidth detection,
+		// ignore local bandwidth config and use BBR
+		congestion.UseBBR(conn)
+	} else {
 		// actualTx = min(serverRx, clientTx)
-	actualTx := serverRx
+		actualTx := authResp.Rx
 		if actualTx == 0 || actualTx > c.config.BandwidthConfig.MaxTx {
+			// Server doesn't have a limit, or our clientTx is smaller than serverRx
 			actualTx = c.config.BandwidthConfig.MaxTx
 		}
-	// Use Brutal CC if actualTx > 0, otherwise use BBR
 		if actualTx > 0 {
-		conn.SetCongestionControl(brutal.NewBrutalSender(actualTx))
+			congestion.UseBrutal(conn, actualTx)
 		} else {
-		conn.SetCongestionControl(bbr.NewBBRSender(
+			// We don't know our own bandwidth either, use BBR
-			bbr.DefaultClock{},
+			congestion.UseBBR(conn)
-			bbr.GetInitialPacketSize(conn.RemoteAddr()),
+		}
-			bbr.InitialCongestionWindow*common.InitMaxDatagramSize,
-			bbr.DefaultBBRMaxCongestionWindow*common.InitMaxDatagramSize,
-		))
 	}
 	_ = resp.Body.Close()
 
 	c.pktConn = pktConn
 	c.conn = conn
-	if udpEnabled {
+	if authResp.UDPEnabled {
 		c.udpSM = newUDPSessionManager(&udpIOImpl{Conn: conn})
 	}
 	return nil

core/internal/congestion/utils.go

@@ -0,0 +1,21 @@
+package congestion
+
+import (
+	"github.com/apernet/hysteria/core/internal/congestion/bbr"
+	"github.com/apernet/hysteria/core/internal/congestion/brutal"
+	"github.com/apernet/hysteria/core/internal/congestion/common"
+	"github.com/apernet/quic-go"
+)
+
+func UseBBR(conn quic.Connection) {
+	conn.SetCongestionControl(bbr.NewBBRSender(
+		bbr.DefaultClock{},
+		bbr.GetInitialPacketSize(conn.RemoteAddr()),
+		bbr.InitialCongestionWindow*common.InitMaxDatagramSize,
+		bbr.DefaultBBRMaxCongestionWindow*common.InitMaxDatagramSize,
+	))
+}
+
+func UseBrutal(conn quic.Connection, tx uint64) {
+	conn.SetCongestionControl(brutal.NewBrutalSender(tx))
+}

core/internal/protocol/http.go

@@ -17,26 +17,52 @@ const (
 	StatusAuthOK = 233
 )
 
-func AuthRequestDataFromHeader(h http.Header) (auth string, rx uint64) {
+// AuthRequest is what client sends to server for authentication.
-	auth = h.Get(RequestHeaderAuth)
+type AuthRequest struct {
-	rx, _ = strconv.ParseUint(h.Get(CommonHeaderCCRX), 10, 64)
+	Auth string
-	return
+	Rx   uint64 // 0 = unknown, client asks server to use bandwidth detection
 }
 
-func AuthRequestDataToHeader(h http.Header, auth string, rx uint64) {
+// AuthResponse is what server sends to client when authentication is passed.
-	h.Set(RequestHeaderAuth, auth)
+type AuthResponse struct {
-	h.Set(CommonHeaderCCRX, strconv.FormatUint(rx, 10))
+	UDPEnabled bool
+	Rx         uint64 // 0 = unlimited
+	RxAuto     bool   // true = server asks client to use bandwidth detection
+}
+
+func AuthRequestFromHeader(h http.Header) AuthRequest {
+	rx, _ := strconv.ParseUint(h.Get(CommonHeaderCCRX), 10, 64)
+	return AuthRequest{
+		Auth: h.Get(RequestHeaderAuth),
+		Rx:   rx,
+	}
+}
+
+func AuthRequestToHeader(h http.Header, req AuthRequest) {
+	h.Set(RequestHeaderAuth, req.Auth)
+	h.Set(CommonHeaderCCRX, strconv.FormatUint(req.Rx, 10))
 	h.Set(CommonHeaderPadding, authRequestPadding.String())
 }
 
-func AuthResponseDataFromHeader(h http.Header) (udp bool, rx uint64) {
+func AuthResponseFromHeader(h http.Header) AuthResponse {
-	udp, _ = strconv.ParseBool(h.Get(ResponseHeaderUDPEnabled))
+	resp := AuthResponse{}
-	rx, _ = strconv.ParseUint(h.Get(CommonHeaderCCRX), 10, 64)
+	resp.UDPEnabled, _ = strconv.ParseBool(h.Get(ResponseHeaderUDPEnabled))
-	return
+	rxStr := h.Get(CommonHeaderCCRX)
+	if rxStr == "auto" {
+		// Special case for server requesting client to use bandwidth detection
+		resp.RxAuto = true
+	} else {
+		resp.Rx, _ = strconv.ParseUint(rxStr, 10, 64)
+	}
+	return resp
 }
 
-func AuthResponseDataToHeader(h http.Header, udp bool, rx uint64) {
+func AuthResponseToHeader(h http.Header, resp AuthResponse) {
-	h.Set(ResponseHeaderUDPEnabled, strconv.FormatBool(udp))
+	h.Set(ResponseHeaderUDPEnabled, strconv.FormatBool(resp.UDPEnabled))
-	h.Set(CommonHeaderCCRX, strconv.FormatUint(rx, 10))
+	if resp.RxAuto {
+		h.Set(CommonHeaderCCRX, "auto")
+	} else {
+		h.Set(CommonHeaderCCRX, strconv.FormatUint(resp.Rx, 10))
+	}
 	h.Set(CommonHeaderPadding, authResponsePadding.String())
 }

core/server/config.go

@@ -24,6 +24,7 @@ type Config struct {
 	Conn                  net.PacketConn
 	Outbound              Outbound
 	BandwidthConfig       BandwidthConfig
+	IgnoreClientBandwidth bool
 	DisableUDP            bool
 	UDPIdleTimeout        time.Duration
 	Authenticator         Authenticator

core/server/server.go

@@ -9,9 +9,7 @@ import (
 	"github.com/apernet/quic-go"
 	"github.com/apernet/quic-go/http3"
 
-	"github.com/apernet/hysteria/core/internal/congestion/bbr"
+	"github.com/apernet/hysteria/core/internal/congestion"
-	"github.com/apernet/hysteria/core/internal/congestion/brutal"
-	"github.com/apernet/hysteria/core/internal/congestion/common"
 	"github.com/apernet/hysteria/core/internal/protocol"
 	"github.com/apernet/hysteria/core/internal/utils"
 )
@@ -96,9 +94,9 @@ type h3sHandler struct {
 	conn   quic.Connection
 
 	authenticated bool
+	authMutex     sync.Mutex
 	authID        string
 
-	udpOnce sync.Once
 	udpSM *udpSessionManager // Only set after authentication
 }
 
@@ -111,36 +109,49 @@ func newH3sHandler(config *Config, conn quic.Connection) *h3sHandler {
 
 func (h *h3sHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	if r.Method == http.MethodPost && r.Host == protocol.URLHost && r.URL.Path == protocol.URLPath {
+		h.authMutex.Lock()
+		defer h.authMutex.Unlock()
 		if h.authenticated {
 			// Already authenticated
-			protocol.AuthResponseDataToHeader(w.Header(), !h.config.DisableUDP, h.config.BandwidthConfig.MaxRx)
+			protocol.AuthResponseToHeader(w.Header(), protocol.AuthResponse{
+				UDPEnabled: !h.config.DisableUDP,
+				Rx:         h.config.BandwidthConfig.MaxRx,
+				RxAuto:     h.config.IgnoreClientBandwidth,
+			})
 			w.WriteHeader(protocol.StatusAuthOK)
 			return
 		}
-		auth, clientRx := protocol.AuthRequestDataFromHeader(r.Header)
+		authReq := protocol.AuthRequestFromHeader(r.Header)
-		// actualTx = min(serverTx, clientRx)
+		actualTx := authReq.Rx
-		actualTx := clientRx
+		ok, id := h.config.Authenticator.Authenticate(h.conn.RemoteAddr(), authReq.Auth, actualTx)
-		if h.config.BandwidthConfig.MaxTx > 0 && actualTx > h.config.BandwidthConfig.MaxTx {
-			actualTx = h.config.BandwidthConfig.MaxTx
-		}
-		ok, id := h.config.Authenticator.Authenticate(h.conn.RemoteAddr(), auth, actualTx)
 		if ok {
 			// Set authenticated flag
 			h.authenticated = true
 			h.authID = id
-			// Use Brutal CC if actualTx > 0, otherwise use BBR
+			if h.config.IgnoreClientBandwidth {
-			if actualTx > 0 {
+				// Ignore client bandwidth, always use BBR
-				h.conn.SetCongestionControl(brutal.NewBrutalSender(actualTx))
+				congestion.UseBBR(h.conn)
+				actualTx = 0
 			} else {
-				h.conn.SetCongestionControl(bbr.NewBBRSender(
+				// actualTx = min(serverTx, clientRx)
-					bbr.DefaultClock{},
+				if h.config.BandwidthConfig.MaxTx > 0 && actualTx > h.config.BandwidthConfig.MaxTx {
-					bbr.GetInitialPacketSize(h.conn.RemoteAddr()),
+					// We have a maxTx limit and the client is asking for more than that,
-					bbr.InitialCongestionWindow*common.InitMaxDatagramSize,
+					// return and use the limit instead
-					bbr.DefaultBBRMaxCongestionWindow*common.InitMaxDatagramSize,
+					actualTx = h.config.BandwidthConfig.MaxTx
-				))
+				}
+				if actualTx > 0 {
+					congestion.UseBrutal(h.conn, actualTx)
+				} else {
+					// Client doesn't know its own bandwidth, use BBR
+					congestion.UseBBR(h.conn)
+				}
 			}
 			// Auth OK, send response
-			protocol.AuthResponseDataToHeader(w.Header(), !h.config.DisableUDP, h.config.BandwidthConfig.MaxRx)
+			protocol.AuthResponseToHeader(w.Header(), protocol.AuthResponse{
+				UDPEnabled: !h.config.DisableUDP,
+				Rx:         h.config.BandwidthConfig.MaxRx,
+				RxAuto:     h.config.IgnoreClientBandwidth,
+			})
 			w.WriteHeader(protocol.StatusAuthOK)
 			// Call event logger
 			if h.config.EventLogger != nil {
@@ -150,14 +161,14 @@ func (h *h3sHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 			// We use sync.Once to make sure that only one goroutine is started,
 			// as ServeHTTP may be called by multiple goroutines simultaneously
 			if !h.config.DisableUDP {
-				h.udpOnce.Do(func() {
+				go func() {
 					sm := newUDPSessionManager(
 						&udpIOImpl{h.conn, id, h.config.TrafficLogger, h.config.Outbound},
 						&udpEventLoggerImpl{h.conn, id, h.config.EventLogger},
 						h.config.UDPIdleTimeout)
 					h.udpSM = sm
 					go sm.Run()
-				})
+				}()
 			}
 		} else {
 			// Auth failed, pretend to be a normal HTTP server