all unix.* ops

overlay/tun_linux.go

@@ -238,6 +238,22 @@ func (t *tun) SupportsMultiqueue() bool {
 	return true
 }
 
+type MultiQueueReader struct {
+	fd int
+}
+
+func (m *MultiQueueReader) Read(p []byte) (int, error) {
+	return unix.Read(m.fd, p)
+}
+
+func (m *MultiQueueReader) Close() error {
+	return unix.Close(m.fd)
+}
+
+func (m *MultiQueueReader) Write(p []byte) (int, error) {
+	return write(m.fd, p)
+}
+
 func (t *tun) NewMultiQueueReader() (io.ReadWriteCloser, error) {
 	fd, err := unix.Open("/dev/net/tun", os.O_RDWR, 0)
 	if err != nil {
@@ -248,12 +264,11 @@ func (t *tun) NewMultiQueueReader() (io.ReadWriteCloser, error) {
 	req.Flags = uint16(unix.IFF_TUN | unix.IFF_NO_PI | unix.IFF_MULTI_QUEUE)
 	copy(req.Name[:], t.Device)
 	if err = ioctl(uintptr(fd), uintptr(unix.TUNSETIFF), uintptr(unsafe.Pointer(&req))); err != nil {
+		_ = unix.Close(fd)
 		return nil, err
 	}
 
-	file := os.NewFile(uintptr(fd), "/dev/net/tun")
+	return &MultiQueueReader{fd: fd}, nil
-
-	return file, nil
 }
 
 func (t *tun) RoutesFor(ip netip.Addr) routing.Gateways {
@@ -261,12 +276,12 @@ func (t *tun) RoutesFor(ip netip.Addr) routing.Gateways {
 	return r
 }
 
-func (t *tun) Write(b []byte) (int, error) {
+func write(fd int, b []byte) (int, error) {
 	var nn int
 	maximum := len(b)
 
 	for {
-		n, err := unix.Write(t.fd, b[nn:maximum])
+		n, err := unix.Write(fd, b[nn:maximum])
 		if n > 0 {
 			nn += n
 		}
@@ -284,6 +299,14 @@ func (t *tun) Write(b []byte) (int, error) {
 	}
 }
 
+func (t *tun) Read(p []byte) (int, error) {
+	return unix.Read(t.fd, p)
+}
+
+func (t *tun) Write(b []byte) (int, error) {
+	return write(t.fd, b)
+}
+
 func (t *tun) deviceBytes() (o [16]byte) {
 	for i, c := range t.Device {
 		o[i] = byte(c)