tun: only call .Fd() once

Doing so tends to make the tunnel blocking, so we only retrieve it once
before we call SetNonblock, and then cache the result.
This commit is contained in:
Jason A. Donenfeld 2018-10-17 21:26:53 +02:00
parent 85b2378a07
commit 2e772194cf
4 changed files with 67 additions and 61 deletions

View file

@ -37,7 +37,8 @@ type sockaddrCtl struct {
type nativeTun struct {
name string
fd *os.File
tunFile *os.File
fd uintptr
rwcancel *rwcancel.RWCancel
events chan TUNEvent
errors chan error
@ -171,14 +172,15 @@ func CreateTUN(name string, mtu int) (TUNDevice, error) {
func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
tun := &nativeTun{
fd: file,
tunFile: file,
fd: file.Fd(),
events: make(chan TUNEvent, 10),
errors: make(chan error, 1),
}
name, err := tun.Name()
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
@ -190,19 +192,19 @@ func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
return iface.Index, nil
}()
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
tun.rwcancel, err = rwcancel.NewRWCancel(int(file.Fd()))
tun.rwcancel, err = rwcancel.NewRWCancel(int(tun.fd))
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
tun.routeSocket, err = unix.Socket(unix.AF_ROUTE, unix.SOCK_RAW, unix.AF_UNSPEC)
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
@ -226,7 +228,7 @@ func (tun *nativeTun) Name() (string, error) {
_, _, errno := unix.Syscall6(
unix.SYS_GETSOCKOPT,
uintptr(tun.fd.Fd()),
uintptr(tun.fd),
2, /* #define SYSPROTO_CONTROL 2 */
2, /* #define UTUN_OPT_IFNAME 2 */
uintptr(unsafe.Pointer(&ifName)),
@ -241,7 +243,7 @@ func (tun *nativeTun) Name() (string, error) {
}
func (tun *nativeTun) File() *os.File {
return tun.fd
return tun.tunFile
}
func (tun *nativeTun) Events() chan TUNEvent {
@ -254,7 +256,7 @@ func (tun *nativeTun) doRead(buff []byte, offset int) (int, error) {
return 0, err
default:
buff := buff[offset-4:]
n, err := tun.fd.Read(buff[:])
n, err := tun.tunFile.Read(buff[:])
if n < 4 {
return 0, err
}
@ -294,13 +296,13 @@ func (tun *nativeTun) Write(buff []byte, offset int) (int, error) {
// write
return tun.fd.Write(buff)
return tun.tunFile.Write(buff)
}
func (tun *nativeTun) Close() error {
var err3 error
err1 := tun.rwcancel.Cancel()
err2 := tun.fd.Close()
err2 := tun.tunFile.Close()
if tun.routeSocket != -1 {
unix.Shutdown(tun.routeSocket, unix.SHUT_RDWR)
err3 = unix.Close(tun.routeSocket)

View file

@ -51,7 +51,8 @@ type ifstat struct {
type nativeTun struct {
name string
fd *os.File
tunFile *os.File
fd uintptr
rwcancel *rwcancel.RWCancel
events chan TUNEvent
errors chan error
@ -237,15 +238,15 @@ func CreateTUN(name string, mtu int) (TUNDevice, error) {
return nil, fmt.Errorf("interface %s already exists", name)
}
tunfile, err := os.OpenFile("/dev/tun", unix.O_RDWR, 0)
tunFile, err := os.OpenFile("/dev/tun", unix.O_RDWR, 0)
if err != nil {
return nil, err
}
tunfd := tunfile.Fd()
tunfd := tunFile.Fd()
assignedName, err := tunName(tunfd)
if err != nil {
tunfile.Close()
tunFile.Close()
return nil, err
}
@ -293,25 +294,26 @@ func CreateTUN(name string, mtu int) (TUNDevice, error) {
uintptr(unsafe.Pointer(&ifr)),
)
if errno != 0 {
tunfile.Close()
tunFile.Close()
tunDestroy(name)
return nil, fmt.Errorf("failed to rename %s to %s: %s", assignedName, name, errno.Error())
}
return CreateTUNFromFile(tunfile, mtu)
return CreateTUNFromFile(tunFile, mtu)
}
func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
tun := &nativeTun{
fd: file,
tunFile: file,
fd: file.Fd(),
events: make(chan TUNEvent, 10),
errors: make(chan error, 1),
}
name, err := tun.Name()
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
@ -323,19 +325,19 @@ func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
return iface.Index, nil
}()
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
tun.rwcancel, err = rwcancel.NewRWCancel(int(file.Fd()))
tun.rwcancel, err = rwcancel.NewRWCancel(int(tun.fd))
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
tun.routeSocket, err = unix.Socket(unix.AF_ROUTE, unix.SOCK_RAW, unix.AF_UNSPEC)
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
@ -351,7 +353,7 @@ func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
}
func (tun *nativeTun) Name() (string, error) {
name, err := tunName(tun.fd.Fd())
name, err := tunName(tun.fd)
if err != nil {
return "", err
}
@ -360,7 +362,7 @@ func (tun *nativeTun) Name() (string, error) {
}
func (tun *nativeTun) File() *os.File {
return tun.fd
return tun.tunFile
}
func (tun *nativeTun) Events() chan TUNEvent {
@ -373,7 +375,7 @@ func (tun *nativeTun) doRead(buff []byte, offset int) (int, error) {
return 0, err
default:
buff := buff[offset-4:]
n, err := tun.fd.Read(buff[:])
n, err := tun.tunFile.Read(buff[:])
if n < 4 {
return 0, err
}
@ -413,13 +415,13 @@ func (tun *nativeTun) Write(buff []byte, offset int) (int, error) {
// write
return tun.fd.Write(buff)
return tun.tunFile.Write(buff)
}
func (tun *nativeTun) Close() error {
var err4 error
err1 := tun.rwcancel.Cancel()
err2 := tun.fd.Close()
err2 := tun.tunFile.Close()
err3 := tunDestroy(tun.name)
if tun.routeSocket != -1 {
unix.Shutdown(tun.routeSocket, unix.SHUT_RDWR)

View file

@ -29,7 +29,8 @@ const (
)
type nativeTun struct {
fd *os.File
tunFile *os.File
fd uintptr
fdCancel *rwcancel.RWCancel
index int32 // if index
name string // name of interface
@ -43,7 +44,7 @@ type nativeTun struct {
}
func (tun *nativeTun) File() *os.File {
return tun.fd
return tun.tunFile
}
func (tun *nativeTun) routineHackListener() {
@ -51,7 +52,7 @@ func (tun *nativeTun) routineHackListener() {
/* This is needed for the detection to work across network namespaces
* If you are reading this and know a better method, please get in touch.
*/
fd := int(tun.fd.Fd())
fd := int(tun.fd)
for {
_, err := unix.Write(fd, nil)
switch err {
@ -266,7 +267,7 @@ func (tun *nativeTun) Name() (string, error) {
var ifr [ifReqSize]byte
_, _, errno := unix.Syscall(
unix.SYS_IOCTL,
tun.fd.Fd(),
tun.fd,
uintptr(unix.TUNGETIFF),
uintptr(unsafe.Pointer(&ifr[0])),
)
@ -307,7 +308,7 @@ func (tun *nativeTun) Write(buff []byte, offset int) (int, error) {
// write
return tun.fd.Write(buff)
return tun.tunFile.Write(buff)
}
func (tun *nativeTun) doRead(buff []byte, offset int) (int, error) {
@ -316,10 +317,10 @@ func (tun *nativeTun) doRead(buff []byte, offset int) (int, error) {
return 0, err
default:
if tun.nopi {
return tun.fd.Read(buff[offset:])
return tun.tunFile.Read(buff[offset:])
} else {
buff := buff[offset-4:]
n, err := tun.fd.Read(buff[:])
n, err := tun.tunFile.Read(buff[:])
if n < 4 {
return 0, err
}
@ -354,7 +355,7 @@ func (tun *nativeTun) Close() error {
} else if tun.events != nil {
close(tun.events)
}
err2 := tun.fd.Close()
err2 := tun.tunFile.Close()
err3 := tun.fdCancel.Cancel()
if err1 != nil {
@ -413,7 +414,8 @@ func CreateTUN(name string, mtu int) (TUNDevice, error) {
func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
tun := &nativeTun{
fd: file,
tunFile: file,
fd: file.Fd(),
events: make(chan TUNEvent, 5),
errors: make(chan error, 5),
statusListenersShutdown: make(chan struct{}),
@ -421,15 +423,15 @@ func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
}
var err error
tun.fdCancel, err = rwcancel.NewRWCancel(int(file.Fd()))
tun.fdCancel, err = rwcancel.NewRWCancel(int(tun.fd))
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
_, err = tun.Name()
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
@ -442,12 +444,12 @@ func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
tun.netlinkSock, err = createNetlinkSocket()
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
tun.netlinkCancel, err = rwcancel.NewRWCancel(tun.netlinkSock)
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}

View file

@ -29,7 +29,7 @@ const _TUNSIFMODE = 0x8004745d
type nativeTun struct {
name string
fd *os.File
tunFile *os.File
rwcancel *rwcancel.RWCancel
events chan TUNEvent
errors chan error
@ -144,14 +144,14 @@ func CreateTUN(name string, mtu int) (TUNDevice, error) {
func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
tun := &nativeTun{
fd: file,
tunFile: file,
events: make(chan TUNEvent, 10),
errors: make(chan error, 1),
}
name, err := tun.Name()
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
@ -163,19 +163,19 @@ func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
return iface.Index, nil
}()
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
tun.rwcancel, err = rwcancel.NewRWCancel(int(file.Fd()))
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
tun.routeSocket, err = unix.Socket(unix.AF_ROUTE, unix.SOCK_RAW, unix.AF_UNSPEC)
if err != nil {
tun.fd.Close()
tun.tunFile.Close()
return nil, err
}
@ -191,7 +191,7 @@ func CreateTUNFromFile(file *os.File, mtu int) (TUNDevice, error) {
}
func (tun *nativeTun) Name() (string, error) {
gostat, err := tun.fd.Stat()
gostat, err := tun.tunFile.Stat()
if err != nil {
tun.name = ""
return "", err
@ -202,7 +202,7 @@ func (tun *nativeTun) Name() (string, error) {
}
func (tun *nativeTun) File() *os.File {
return tun.fd
return tun.tunFile
}
func (tun *nativeTun) Events() chan TUNEvent {
@ -215,7 +215,7 @@ func (tun *nativeTun) doRead(buff []byte, offset int) (int, error) {
return 0, err
default:
buff := buff[offset-4:]
n, err := tun.fd.Read(buff[:])
n, err := tun.tunFile.Read(buff[:])
if n < 4 {
return 0, err
}
@ -255,13 +255,13 @@ func (tun *nativeTun) Write(buff []byte, offset int) (int, error) {
// write
return tun.fd.Write(buff)
return tun.tunFile.Write(buff)
}
func (tun *nativeTun) Close() error {
var err3 error
err1 := tun.rwcancel.Cancel()
err2 := tun.fd.Close()
err2 := tun.tunFile.Close()
if tun.routeSocket != -1 {
unix.Shutdown(tun.routeSocket, unix.SHUT_RDWR)
err3 = unix.Close(tun.routeSocket)