tun: use SockaddrCtl from golang.org/x/sys/unix on macOS

Direct syscalls using unix.Syscall(unix.SYS_*, ...) are discouraged on
macOS and might not be supported in future versions. Switch to use
unix.Connect with unix.SockaddrCtl instead.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This commit is contained in:
Tobias Klauser 2020-10-27 14:39:36 +01:00 committed by Jason A. Donenfeld
parent e6b7c4eef3
commit 3b490f30aa

View File

@ -20,16 +20,6 @@ import (
const utunControlName = "com.apple.net.utun_control" const utunControlName = "com.apple.net.utun_control"
// sockaddr_ctl specifeid in /usr/include/sys/kern_control.h
type sockaddrCtl struct {
scLen uint8
scFamily uint8
ssSysaddr uint16
scID uint32
scUnit uint32
scReserved [5]uint32
}
type NativeTun struct { type NativeTun struct {
name string name string
tunFile *os.File tunFile *os.File
@ -38,8 +28,6 @@ type NativeTun struct {
routeSocket int routeSocket int
} }
var sockaddrCtlSize uintptr = 32
func retryInterfaceByIndex(index int) (iface *net.Interface, err error) { func retryInterfaceByIndex(index int) (iface *net.Interface, err error) {
for i := 0; i < 20; i++ { for i := 0; i < 20; i++ {
iface, err = net.InterfaceByIndex(index) iface, err = net.InterfaceByIndex(index)
@ -134,25 +122,14 @@ func CreateTUN(name string, mtu int) (Device, error) {
return nil, fmt.Errorf("IoctlGetCtlInfo: %w", err) return nil, fmt.Errorf("IoctlGetCtlInfo: %w", err)
} }
sc := sockaddrCtl{ sc := &unix.SockaddrCtl{
scLen: uint8(sockaddrCtlSize), ID: ctlInfo.Id,
scFamily: unix.AF_SYSTEM, Unit: uint32(ifIndex) + 1,
ssSysaddr: 2,
scID: ctlInfo.Id,
scUnit: uint32(ifIndex) + 1,
} }
scPointer := unsafe.Pointer(&sc) err = unix.Connect(fd, sc)
if err != nil {
_, _, errno = unix.RawSyscall( return nil, err
unix.SYS_CONNECT,
uintptr(fd),
uintptr(scPointer),
uintptr(sockaddrCtlSize),
)
if errno != 0 {
return nil, fmt.Errorf("SYS_CONNECT: %v", errno)
} }
err = syscall.SetNonblock(fd, true) err = syscall.SetNonblock(fd, true)