Commit Graph

26 Commits

Author SHA1 Message Date
Brad Fitzpatrick
2fb0a712f0 tun: return a better error message if /dev/net/tun doesn't exist
It was just returning "no such file or directory" (the String of the
syscall.Errno returned by CreateTUN).

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2020-05-02 01:50:47 -06:00
Avery Pennarun
c76b818466 tun: NetlinkListener: don't send EventDown before sending EventUp
This works around a startup race condition when competing with
HackListener, which is trying to do the same job. If HackListener
detects that the tundev is running while there is still an event in the
netlink queue that says it isn't running, then the device receives a
string of events like
	EventUp (HackListener)
	EventDown (NetlinkListener)
	EventUp (NetlinkListener)
Unfortunately, after the first EventDown, the device stops itself,
thinking incorrectly that the administrator has downed its tundev.

The device is ignoring the initial EventDown anyway, so just don't emit
it.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
2020-05-02 01:46:42 -06:00
Brad Fitzpatrick
85a45a9651 tun: fix data race on name field
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2020-05-02 01:46:42 -06:00
Brad Fitzpatrick
abd287159e tun: remove unused isUp method
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2020-05-02 01:46:42 -06:00
Tobias Klauser
b33219c2cf global: use RTMGRP_* consts from x/sys/unix
Update the golang.org/x/sys/unix dependency and use the newly introduced
RTMGRP_* consts instead of using the corresponding RTNLGRP_* const to
create a mask.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2020-03-17 23:07:11 -06:00
Jonathan Tooker
f7d0edd2ec global: fix a few typos courtesy of codespell
Signed-off-by: Jonathan Tooker <jonathan.tooker@netprotect.com>
2019-10-22 11:51:25 +02:00
Matt Layher
1f48971a80 tun: remove TUN prefix from types to reduce stutter elsewhere
Signed-off-by: Matt Layher <mdlayher@gmail.com>
2019-06-14 18:35:57 +02:00
Jason A. Donenfeld
eaf17becfa global: fixup TODO comment spacing 2019-06-06 23:00:15 +02:00
Jason A. Donenfeld
3bf41b06ae global: regroup all imports 2019-05-14 09:09:52 +02:00
Jason A. Donenfeld
6440f010ee receive: implement flush semantics 2019-03-21 14:45:41 -06:00
Jason A. Donenfeld
92f72f5aa6 tun: linux: work out netpoll trick 2019-03-07 01:51:41 +01:00
Jason A. Donenfeld
68f0721c6a tun: import mobile particularities 2019-03-04 16:37:11 +01:00
Jason A. Donenfeld
967d1a0f3d tun: allow special methods in NativeTun 2019-03-01 00:05:57 +01:00
Jason A. Donenfeld
88ff67fb6f tun: linux: netpoll is broken for tun's epoll
So this mostly reverts the switch to Sysconn for Linux.

Issue: https://github.com/golang/go/issues/30426
2019-02-27 04:38:26 +01:00
Jason A. Donenfeld
971be13e77 tun: linux: netlink sock needs cleaning up but file will be gc'd 2019-02-27 04:11:41 +01:00
Jason A. Donenfeld
366cbd11a4 tun: use netpoll instead of rwcancel
The new sysconn function of Go 1.12 makes this possible:

package main

import "log"
import "os"
import "unsafe"
import "time"
import "syscall"
import "sync"
import "golang.org/x/sys/unix"

func main() {
	fd, err := os.OpenFile("/dev/net/tun", os.O_RDWR, 0)
	if err != nil {
		log.Fatal(err)
	}

	var ifr [unix.IFNAMSIZ + 64]byte
	copy(ifr[:], []byte("cheese"))
	*(*uint16)(unsafe.Pointer(&ifr[unix.IFNAMSIZ])) = unix.IFF_TUN

	var errno syscall.Errno
	s, _ := fd.SyscallConn()
	s.Control(func(fd uintptr) {
		_, _, errno = unix.Syscall(
			unix.SYS_IOCTL,
			fd,
			uintptr(unix.TUNSETIFF),
			uintptr(unsafe.Pointer(&ifr[0])),
		)
	})
	if errno != 0 {
		log.Fatal(errno)
	}

	b := [4]byte{}
	wait := sync.WaitGroup{}
	wait.Add(1)
	go func() {
		_, err := fd.Read(b[:])
		log.Print("Read errored: ", err)
		wait.Done()
	}()
	time.Sleep(time.Second)
	log.Print("Closing")
	err = fd.Close()
	if err != nil {
		log.Print("Close errored: " , err)
	}
	wait.Wait()
	log.Print("Exiting")
}
2019-02-27 01:52:55 +01:00
Jason A. Donenfeld
ab0f442daf tun: use sysconn instead of .Fd with Go 1.12 2019-02-27 01:34:11 +01:00
Jason A. Donenfeld
42c6d0e261 Change package path 2019-02-18 05:11:39 +01:00
Jason A. Donenfeld
dff424baf8 Update copyright 2019-02-05 12:59:42 +01:00
Jason A. Donenfeld
651744561e tun: remove nonblock hack for linux
This is no longer necessary and actually breaks things

Reported-by: Chris Branch <cbranch@cloudflare.com>
2018-12-06 17:17:51 +01:00
Jason A. Donenfeld
2e772194cf 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.
2018-10-17 21:31:42 +02:00
Jason A. Donenfeld
5be541d147 global: fix up copyright headers 2018-09-16 18:49:19 +02:00
Jason A. Donenfeld
15da869b31 Fix duplicate copyright line 2018-07-30 05:14:17 +02:00
Jason A. Donenfeld
2f2eca8947 Catch EINTR 2018-05-24 15:36:29 +02:00
Jason A. Donenfeld
588b9f01ae Adopt GOPATH
GOPATH is annoying, but the Go community pushing me to adopt it is even
more annoying.
2018-05-23 05:18:13 +02:00
Jason A. Donenfeld
0a63188afa Move tun to subpackage 2018-05-23 03:58:27 +02:00