Add v2ray QUIC transport

transport/v2rayquic/server.go

@@ -0,0 +1,95 @@
+package v2rayquic
+
+import (
+	"context"
+	"crypto/tls"
+	"net"
+	"os"
+
+	"github.com/sagernet/quic-go"
+	"github.com/sagernet/sing-box/adapter"
+	C "github.com/sagernet/sing-box/constant"
+	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing-box/transport/hysteria"
+	"github.com/sagernet/sing/common"
+	E "github.com/sagernet/sing/common/exceptions"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+)
+
+var _ adapter.V2RayServerTransport = (*Server)(nil)
+
+type Server struct {
+	ctx          context.Context
+	tlsConfig    *tls.Config
+	quicConfig   *quic.Config
+	handler      N.TCPConnectionHandler
+	errorHandler E.Handler
+	udpListener  net.PacketConn
+	quicListener quic.Listener
+}
+
+func NewServer(ctx context.Context, options option.V2RayQUICOptions, tlsConfig *tls.Config, handler N.TCPConnectionHandler, errorHandler E.Handler) *Server {
+	quicConfig := &quic.Config{
+		DisablePathMTUDiscovery: !C.IsLinux && !C.IsWindows,
+	}
+	if len(tlsConfig.NextProtos) == 0 {
+		tlsConfig.NextProtos = []string{"h2", "http/1.1"}
+	}
+	server := &Server{
+		ctx:          ctx,
+		tlsConfig:    tlsConfig,
+		quicConfig:   quicConfig,
+		handler:      handler,
+		errorHandler: errorHandler,
+	}
+	return server
+}
+
+func (s *Server) Network() []string {
+	return []string{N.NetworkUDP}
+}
+
+func (s *Server) Serve(listener net.Listener) error {
+	return os.ErrInvalid
+}
+
+func (s *Server) ServePacket(listener net.PacketConn) error {
+	quicListener, err := quic.Listen(listener, s.tlsConfig, s.quicConfig)
+	if err != nil {
+		return err
+	}
+	s.udpListener = listener
+	s.quicListener = quicListener
+	go s.acceptLoop()
+	return nil
+}
+
+func (s *Server) acceptLoop() {
+	for {
+		conn, err := s.quicListener.Accept(s.ctx)
+		if err != nil {
+			return
+		}
+		go func() {
+			hErr := s.streamAcceptLoop(conn)
+			if hErr != nil {
+				s.errorHandler.NewError(conn.Context(), hErr)
+			}
+		}()
+	}
+}
+
+func (s *Server) streamAcceptLoop(conn quic.Connection) error {
+	for {
+		stream, err := conn.AcceptStream(s.ctx)
+		if err != nil {
+			return err
+		}
+		go s.handler.NewConnection(conn.Context(), &hysteria.StreamWrapper{Conn: conn, Stream: stream}, M.Metadata{})
+	}
+}
+
+func (s *Server) Close() error {
+	return common.Close(s.udpListener, s.quicListener)
+}