Add brutal infra

common/mux/client.go

@@ -170,7 +170,7 @@ func (f *DialingWorkerFactory) Create() (*ClientWorker, error) {
 
 type ClientStrategy struct {
 	MaxConcurrency uint32
-	MaxConnection  uint32
+	MaxReuseTimes  uint32
 }
 
 type ClientWorker struct {
@@ -288,7 +288,7 @@ func fetchInput(ctx context.Context, s *Session, output buf.Writer) {
 
 func (m *ClientWorker) IsClosing() bool {
 	sm := m.sessionManager
-	if m.strategy.MaxConnection > 0 && sm.Count() >= int(m.strategy.MaxConnection) {
+	if m.strategy.MaxReuseTimes > 0 && sm.Count() >= int(m.strategy.MaxReuseTimes) {
 		return true
 	}
 	return false

common/mux/client_test.go

@@ -58,7 +58,7 @@ func TestClientWorkerClose(t *testing.T) {
 		Writer: w1,
 	}, mux.ClientStrategy{
 		MaxConcurrency: 4,
-		MaxConnection:  4,
+		MaxReuseTimes:  4,
 	})
 	common.Must(err)
 
@@ -68,7 +68,7 @@ func TestClientWorkerClose(t *testing.T) {
 		Writer: w2,
 	}, mux.ClientStrategy{
 		MaxConcurrency: 4,
-		MaxConnection:  4,
+		MaxReuseTimes:  4,
 	})
 	common.Must(err)
 

common/mux/session.go

@@ -56,11 +56,12 @@ func (m *SessionManager) Allocate(Strategy *ClientStrategy) *Session {
 	defer m.Unlock()
 
 	MaxConcurrency := int(Strategy.MaxConcurrency)
-	MaxConnection := uint16(Strategy.MaxConnection)
+	MaxReuseTimes := uint16(Strategy.MaxReuseTimes)
 
-	if m.closed || (MaxConcurrency > 0 && len(m.sessions) >= MaxConcurrency) || (MaxConnection > 0 && m.count >= MaxConnection) {
+	if m.closed || (MaxConcurrency > 0 && len(m.sessions) >= MaxConcurrency) || (MaxReuseTimes > 0 && m.count >= MaxReuseTimes) {
 		return nil
 	}
+	errors.LogInfo(context.Background(), "Allocated mux.cool session id ", m.count, "/", MaxReuseTimes)
 
 	m.count++
 	s := &Session{

transport/internet/brutal/brutal.go

@@ -0,0 +1,53 @@
+//go:build linux
+
+package brutal
+
+import (
+	"os"
+	"unsafe"
+
+	"github.com/xtls/xray-core/common/net"
+	"golang.org/x/sys/unix"
+)
+
+//go:linkname setsockopt syscall.setsockopt
+func setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error)
+
+const (
+	TCP_BRUTAL_PARAMS = 23301
+)
+
+type TCPBrutalParams struct {
+	Rate     uint64
+	CwndGain uint32
+}
+
+func setBrutalFD(fd uintptr, sendBPS uint64) error {
+	err := unix.SetsockoptString(int(fd), unix.IPPROTO_TCP, unix.TCP_CONGESTION, "brutal")
+	if err != nil {
+		return err
+	}
+	params := TCPBrutalParams{
+		Rate:     sendBPS,
+		CwndGain: 20, // hysteria2 default
+	}
+	err = setsockopt(int(fd), unix.IPPROTO_TCP, TCP_BRUTAL_PARAMS, unsafe.Pointer(&params), unsafe.Sizeof(params))
+	if err != nil {
+		return os.NewSyscallError("setsockopt IPPROTO_TCP TCP_BRUTAL_PARAMS", err)
+	}
+	return nil
+}
+
+func SetBrutal(conn *net.TCPConn, sendBPS uint64) error {
+	syscallConn, err := conn.SyscallConn()
+	if err != nil {
+		return err
+	}
+	syscallConn.Control(func(fd uintptr) {
+		err = setBrutalFD(fd, sendBPS)
+	})
+	if err != nil {
+		return err
+	}
+	return nil
+}

transport/internet/brutal/brutal_others.go

@@ -0,0 +1,12 @@
+//go:build !linux
+
+package brutal
+
+import (
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/net"
+)
+
+func SetBrutal(conn *net.TCPConn, sendBPS uint64) error {
+	return errors.New("brutal not available on this platform")
+}