Add gun-lite gRPC implementation (#44)

transport/v2raygrpclite/server.go

@@ -0,0 +1,96 @@
+package v2raygrpclite
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"net"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing-box/option"
+	"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"
+	sHttp "github.com/sagernet/sing/protocol/http"
+)
+
+var _ adapter.V2RayServerTransport = (*Server)(nil)
+
+type Server struct {
+	handler      N.TCPConnectionHandler
+	errorHandler E.Handler
+	httpServer   *http.Server
+	path         string
+}
+
+func (s *Server) Network() []string {
+	return []string{N.NetworkTCP}
+}
+
+func NewServer(ctx context.Context, options option.V2RayGRPCOptions, tlsConfig *tls.Config, handler N.TCPConnectionHandler, errorHandler E.Handler) *Server {
+	server := &Server{
+		handler:      handler,
+		errorHandler: errorHandler,
+		path:         fmt.Sprintf("/%s/Tun", url.QueryEscape(options.ServiceName)),
+	}
+	if tlsConfig != nil {
+		if !common.Contains(tlsConfig.NextProtos, "h2") {
+			tlsConfig.NextProtos = append(tlsConfig.NextProtos, "h2")
+		}
+	}
+	server.httpServer = &http.Server{
+		Handler:   server,
+		TLSConfig: tlsConfig,
+	}
+	return server
+}
+
+func (s *Server) ServeHTTP(writer http.ResponseWriter, request *http.Request) {
+	if request.URL.Path != s.path {
+		writer.WriteHeader(http.StatusNotFound)
+		s.badRequest(request, E.New("bad path: ", request.URL.Path))
+		return
+	}
+	if request.Method != http.MethodPost {
+		writer.WriteHeader(http.StatusNotFound)
+		s.badRequest(request, E.New("bad method: ", request.Method))
+		return
+	}
+	if ct := request.Header.Get("Content-Type"); !strings.HasPrefix(ct, "application/grpc") {
+		writer.WriteHeader(http.StatusNotFound)
+		s.badRequest(request, E.New("bad content type: ", ct))
+		return
+	}
+	writer.Header().Set("Content-Type", "application/grpc")
+	writer.Header().Set("TE", "trailers")
+	writer.WriteHeader(http.StatusOK)
+	var metadata M.Metadata
+	metadata.Source = sHttp.SourceAddress(request)
+	conn := newGunConn(request.Body, writer, writer.(http.Flusher))
+	s.handler.NewConnection(request.Context(), conn, metadata)
+}
+
+func (s *Server) badRequest(request *http.Request, err error) {
+	s.errorHandler.NewError(request.Context(), E.Cause(err, "process connection from ", request.RemoteAddr))
+}
+
+func (s *Server) Serve(listener net.Listener) error {
+	if s.httpServer.TLSConfig == nil {
+		return s.httpServer.Serve(listener)
+	} else {
+		return s.httpServer.ServeTLS(listener, "", "")
+	}
+}
+
+func (s *Server) ServePacket(listener net.PacketConn) error {
+	return os.ErrInvalid
+}
+
+func (s *Server) Close() error {
+	return common.Close(common.PtrOrNil(s.httpServer))
+}