diff options
| -rw-r--r-- | device.go | 8 | ||||
| -rw-r--r-- | tun.go | 2 | ||||
| -rw-r--r-- | tun_linux.go | 25 |
3 files changed, 28 insertions, 7 deletions
@@ -255,7 +255,15 @@ func NewDevice(tun TUNDevice, logger *Logger) *Device { device.isClosed.Set(false) device.log = logger + device.tun.device = tun + mtu, err := device.tun.device.MTU() + if err != nil { + logger.Error.Println("Trouble determining MTU, assuming 1420:", err) + mtu = 1420 + } + device.tun.mtu = int32(mtu) + device.peers.keyMap = make(map[NoisePublicKey]*Peer) // initialize anti-DoS / anti-scanning features @@ -20,7 +20,7 @@ type TUNDevice interface { Read([]byte, int) (int, error) // read a packet from the device (without any additional headers) Write([]byte, int) (int, error) // writes a packet to the device (without any additional headers) MTU() (int, error) // returns the MTU of the device - Name() string // returns the current name + Name() (string, error) // fetches and returns the current name Events() chan TUNEvent // returns a constant channel of events related to the device Close() error // stops the device and closes the event channel } diff --git a/tun_linux.go b/tun_linux.go index da53907..06b5af4 100644 --- a/tun_linux.go +++ b/tun_linux.go @@ -11,6 +11,7 @@ import ( "golang.org/x/sys/unix" "net" "os" + "strconv" "strings" "time" "unsafe" @@ -130,10 +131,6 @@ func (tun *NativeTun) isUp() (bool, error) { return inter.Flags&net.FlagUp != 0, err } -func (tun *NativeTun) Name() string { - return tun.name -} - func getDummySock() (int, error) { return unix.Socket( unix.AF_INET, @@ -229,7 +226,7 @@ func (tun *NativeTun) MTU() (int, error) { uintptr(unsafe.Pointer(&ifr[0])), ) if errno != 0 { - return 0, errors.New("Failed to get MTU of TUN device") + return 0, errors.New("Failed to get MTU of TUN device: " + strconv.FormatInt(int64(errno), 10)) } // convert result to signed 32-bit int @@ -241,6 +238,22 @@ func (tun *NativeTun) MTU() (int, error) { return int(val), nil } +func (tun *NativeTun) Name() (string, error) { + + var ifr [ifReqSize]byte + _, _, errno := unix.Syscall( + unix.SYS_IOCTL, + tun.fd.Fd(), + uintptr(unix.TUNGETIFF), + uintptr(unsafe.Pointer(&ifr[0])), + ) + if errno != 0 { + return "", errors.New("Failed to get name of TUN device: " + strconv.FormatInt(int64(errno), 10)) + } + tun.name = string(ifr[:]) + return tun.name, nil +} + func (tun *NativeTun) Write(buff []byte, offset int) (int, error) { if tun.nopi { @@ -342,7 +355,7 @@ func CreateTUN(name string) (TUNDevice, error) { _, _, errno := unix.Syscall( unix.SYS_IOCTL, - uintptr(fd.Fd()), + fd.Fd(), uintptr(unix.TUNSETIFF), uintptr(unsafe.Pointer(&ifr[0])), ) |