1 files changed, 316 insertions, 0 deletions
diff --git a/tunnel/tools/libwg-go/service.go b/tunnel/tools/libwg-go/service.go
new file mode 100644
index 00000000..f5460486
--- /dev/null
+++ b/tunnel/tools/libwg-go/service.go
@@ -0,0 +1,316 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"net/netip"
+	"net/url"
+	"os"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+
+	gen "golang.zx2c4.com/wireguard/android/gen"
+	"golang.zx2c4.com/wireguard/device"
+)
+
+const (
+	IPPROTO_TCP = 6
+)
+
+type UidRequest struct {
+	Data AddrPortPair
+	RetCh chan string
+}
+
+type LibwgServiceImpl struct {
+	gen.UnimplementedLibwgServer
+	logger *device.Logger
+	httpProxy *HttpProxy
+	uidRequest chan UidRequest
+	stopReverse chan bool
+}
+
+var service *LibwgServiceImpl
+var server *grpc.Server
+
+func NewLibwgService(logger *device.Logger) gen.LibwgServer {
+	return &LibwgServiceImpl{
+		logger: logger,
+		uidRequest: make(chan UidRequest),
+		stopReverse: make(chan bool),
+	}
+}
+
+func StartGrpc(sock_path string, logger *device.Logger) (int, string) {
+	if server != nil {
+		return -1, "Already started"
+	}
+
+	if _, err := os.Stat(sock_path); err == nil {
+		if err := os.RemoveAll(sock_path); err != nil {
+			return -1, fmt.Sprintf("Cleanup failed: %v %v", sock_path, err)
+		}
+	}
+
+	listener, err := net.Listen("unix", sock_path)
+	if err != nil {
+		return -1, fmt.Sprintf("Listen failed: %v %v", sock_path, err)
+	}
+
+	server = grpc.NewServer()
+	service = NewLibwgService(logger).(*LibwgServiceImpl)
+
+	gen.RegisterLibwgServer(server, service)
+
+	go func() {
+		server.Serve(listener)
+	}()
+
+	logger.Verbosef("gRPC started")
+
+	return 0, ""
+}
+
+func (e *LibwgServiceImpl) Version(ctx context.Context, req *gen.VersionRequest) (*gen.VersionResponse, error) {
+
+	r := &gen.VersionResponse{
+		Version: Version(),
+	}
+
+	return r, nil
+}
+
+func (e *LibwgServiceImpl) StopGrpc(ctx context.Context, req *gen.StopGrpcRequest) (*gen.StopGrpcResponse, error) {
+	if server != nil {
+		server.Stop()
+		server = nil
+		service = nil
+	}
+
+	r := &gen.StopGrpcResponse{
+	}
+
+	return r, nil
+}
+
+func buildStartHttpProxyError(message string) (*gen.StartHttpProxyResponse, error) {
+	r := &gen.StartHttpProxyResponse{
+		Error: &gen.Error{
+			Message: message,
+		},
+	}
+	return r, nil
+}
+
+func (e *LibwgServiceImpl) StartHttpProxy(ctx context.Context, req *gen.StartHttpProxyRequest) (*gen.StartHttpProxyResponse, error) {
+	var listenPort uint16
+	if e.httpProxy == nil {
+		e.httpProxy = NewHttpProxy(e.uidRequest, e.logger)
+		var err error
+		listenPort, err = e.httpProxy.Start()
+
+		if err != nil {
+			e.httpProxy = nil
+			return buildStartHttpProxyError(fmt.Sprintf("Http proxy start failed: %v", err))
+		}
+	} else {
+		listenPort = e.httpProxy.GetAddrPort().Port()
+	}
+
+	content := req.GetPacFileContent()
+	if content != "" {
+		err := e.httpProxy.SetPacFileContent(content)
+		if err != nil {
+			return buildStartHttpProxyError(fmt.Sprintf("Bad pacFileContent: %v (%s)", content))
+		}
+	} else {
+		pacFileUrl, err := url.Parse(req.GetPacFileUrl())
+		if err != nil {
+			return buildStartHttpProxyError(fmt.Sprintf("Bad pacFileUrl: %v (%s)", err, req.GetPacFileUrl()))
+		}
+		err = e.httpProxy.SetPacFileUrl(pacFileUrl)
+		if err != nil {
+			return buildStartHttpProxyError(fmt.Sprintf("Bad pacFileUrl: %v (%s)", err, pacFileUrl))
+		}
+	}
+
+	r := &gen.StartHttpProxyResponse{
+		ListenPort: uint32(listenPort),
+	}
+	return r, nil
+}
+
+func (e *LibwgServiceImpl) StopHttpProxy(ctx context.Context, req *gen.StopHttpProxyRequest) (*gen.StopHttpProxyResponse, error) {
+	if e.httpProxy == nil {
+		r := &gen.StopHttpProxyResponse{
+			Error: &gen.Error{
+				Message: fmt.Sprintf("Http proxy not running"),
+			},
+		}
+		return r, nil
+	}
+
+	e.httpProxy.Stop()
+	e.httpProxy = nil
+	e.stopReverse <- true
+	r := &gen.StopHttpProxyResponse{}
+	return r, nil
+}
+
+func (e *LibwgServiceImpl) Reverse(stream gen.Libwg_ReverseServer) error {
+	e.logger.Verbosef("Reverse enter loop")
+	for e.httpProxy != nil {
+		var err error
+
+		//		err := contextError(stream.Context())
+		err = stream.Context().Err()
+		if err != nil {
+			e.logger.Verbosef("Reverse: context: %v", err)
+			return err
+		}
+
+		select {
+		case <-e.stopReverse:
+			e.logger.Verbosef("Reverse: stop")
+			break
+		case uidReq := <-e.uidRequest:
+			addrPortPair := uidReq.Data
+			local := addrPortPair.local
+			remote := addrPortPair.remote
+			r := &gen.ReverseResponse{
+				Request: &gen.ReverseResponse_Uid{
+					Uid: &gen.GetConnectionOwnerUidRequest{
+						Protocol: IPPROTO_TCP,
+						Local: &gen.InetSocketAddress{
+							Address: &gen.InetAddress{
+								Address: local.Addr().AsSlice(),
+							},
+							Port: uint32(local.Port()),
+						},
+						Remote: &gen.InetSocketAddress{
+							Address: &gen.InetAddress{
+								Address: remote.Addr().AsSlice(),
+							},
+							Port: uint32(remote.Port()),
+						},
+					},
+				},
+			}
+
+			stream.Send(r)
+
+			req, err := stream.Recv()
+			if err == io.EOF {
+				e.logger.Verbosef("no more data")
+				uidReq.RetCh <- ""
+				break
+			}
+			if err != nil {
+				err = status.Errorf(codes.Unknown, "cannot receive stream request: %v", err)
+				e.logger.Verbosef("Reverse: %v", err)
+				uidReq.RetCh <- ""
+				return err
+			}
+
+			e.logger.Verbosef("Reverse: received, wait: %v", req)
+			uidReq.RetCh <- req.GetUid().GetPackage()
+		}
+	}
+
+
+	e.logger.Verbosef("Reverse returns")
+	return nil
+}
+
+func (e *LibwgServiceImpl) IpcSet(ctx context.Context, req *gen.IpcSetRequest) (*gen.IpcSetResponse, error) {
+	tunnel, ok := GetTunnel(req.GetTunnel().GetHandle())
+	if !ok {
+		r := &gen.IpcSetResponse{
+			Error: &gen.Error{
+				Message: fmt.Sprintf("Invalid tunnel"),
+			},
+		}
+		return r, nil
+	}
+
+	err := tunnel.device.IpcSet(req.GetConfig())
+	if err != nil {
+		r := &gen.IpcSetResponse{
+			Error: &gen.Error{
+				Message: fmt.Sprintf("IpcSet failed: %v", err),
+			},
+		}
+		return r, nil
+	}
+
+	r := &gen.IpcSetResponse{
+	}
+
+	return r, nil
+}
+
+func (e *LibwgServiceImpl) Dhcp(ctx context.Context, req *gen.DhcpRequest) (*gen.DhcpResponse, error) {
+	var relayAddr netip.Addr
+	var sourceAddr netip.Addr
+
+	source := req.GetSource()
+	if source != nil {
+		sourceAddr, _ = netip.AddrFromSlice(source.GetAddress())
+	}
+
+	if !sourceAddr.IsValid() || !sourceAddr.Is6() {
+		r := &gen.DhcpResponse{
+			Error: &gen.Error{
+				Message: fmt.Sprintf("DHCPv6 source address missing"),
+			},
+		}
+		return r, nil
+	}
+
+	relay := req.GetRelay()
+	if relay != nil {
+		relayAddr, _ = netip.AddrFromSlice(relay.GetAddress())
+	} else {
+		// Construct relay address from source prefix
+		relayRaw := source.GetAddress()[:8]
+		relayRaw = append(relayRaw, 0)
+		relayRaw = append(relayRaw, 0)
+		relayRaw = append(relayRaw, 0)
+		relayRaw = append(relayRaw, 0)
+		relayRaw = append(relayRaw, 0)
+		relayRaw = append(relayRaw, 0)
+		relayRaw = append(relayRaw, 0)
+		relayRaw = append(relayRaw, 1)
+		relayAddr, _ = netip.AddrFromSlice(relayRaw)
+	}
+
+	if !relayAddr.IsValid() || !relayAddr.Is6() {
+		r := &gen.DhcpResponse{
+			Error: &gen.Error{
+				Message: fmt.Sprintf("DHCPv6 relay address calculation failed"),
+			},
+		}
+		return r, nil
+	}
+
+	e.logger.Verbosef("RunDhcp %v %v", sourceAddr, relayAddr)
+
+	leases, err := RunDhcp(ctx, sourceAddr, relayAddr)
+	if err != nil {
+		r := &gen.DhcpResponse{
+			Error: &gen.Error{
+				Message: fmt.Sprintf("RunDhcp failed: %v", err),
+			},
+		}
+		return r, nil
+	}
+
+	r := &gen.DhcpResponse{
+		Leases: leases,
+	}
+	return r, nil
+}