private static int Open_TUNTAP(IntPtr dev, UInt16 flags, bool persistent)
{
var ifr = Marshal.AllocHGlobal(IFR_SIZE); // we need 40 bytes, but we allocate a bit more
var fd = LibCWrapper.Open("/dev/net/tun", O_RDWR);
if (fd < 0)
{
Console.Error.WriteLine("Could not open /dev/net/tun, error: {0}", Marshal.GetLastWin32Error());
return(fd);
}
var memory = new byte[IFR_SIZE];
Array.Clear(memory, 0, IFR_SIZE);
var bytes = BitConverter.GetBytes(flags);
Array.Copy(bytes, 0, memory, IFNAMSIZ, 2);
if (dev != IntPtr.Zero)
{
var devBytes = Encoding.ASCII.GetBytes(Marshal.PtrToStringAnsi(dev));
Array.Copy(devBytes, memory, Math.Min(devBytes.Length, IFNAMSIZ));
}
Marshal.Copy(memory, 0, ifr, IFR_SIZE);
int err = 0;
if ((err = LibCWrapper.Ioctl(fd, TUNSETIFF, ifr)) < 0)
{
Console.Error.WriteLine("Could not set TUNSETIFF, error: {0}", Marshal.GetLastWin32Error());
LibCWrapper.Close(fd);
return(err);
}
if (persistent)
{
if ((err = LibCWrapper.Ioctl(fd, TUNSETPERSIST, 1)) < 0)
{
Console.Error.WriteLine("Could not set TUNSETPERSIST, error: {0}", Marshal.GetLastWin32Error());
LibCWrapper.Close(fd);
return(err);
}
}
LibCWrapper.Strcpy(dev, ifr);
Marshal.FreeHGlobal(ifr);
return(fd);
}
private static bool DoIoctl(IoctlCode code, IntPtr data)
{
int err;
if ((err = LibCWrapper.Ioctl(fd, (int)code, data)) < 0)
{
var lastErrorCode = Marshal.GetLastWin32Error();
var lastErrorMessage = LibCWrapper.Strerror(lastErrorCode);
loggingParent.Log(LogLevel.Error, "There was an error when executing the {0} ioctl: {1} (0x{2:X})", Enum.GetName(typeof(IoctlCode), code), lastErrorMessage, lastErrorCode);
LibCWrapper.Close(fd);
return(false);
}
return(true);
}