Anyone knows how to use it from pascal ?

I am even willing to pay for a component that simplifies TAP-win32 use.

What does TAP stand for?

Felipe Monteiro de Carvalho wrote

What does TAP stand for?

see http://en.wikipedia.org/wiki/TUN/TAP for some pointers.

Marc

TAP-Win32 is the win32 equivalent of linux/unix tun tap devices.

i need to:
- discover installed taps
- set device options (Dont need ip and etc, just the basic ioctls)
- read and write to device (after set up it becomes just a simple file)

i tried this :

Uses Windows, Classes;
Const
	TAP_Device = '\\\\.\\Global\\{44F7688F-77FA-43DC-8D8F-9CBA23E01BB0}.tap';
Var
	Handle : Integer;
	Buffer : Pointer;
	Stream : THandleStream;
	Count  : Integer;
Begin
	Handle := CreateFile(PChar(TAP_Device), GENERIC_READ Or
GENERIC_WRITE, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM Or
FILE_FLAG_OVERLAPPED, 0);
	WriteLn(Handle);
	Stream := THandleStream.Create(Handle);
	Buffer := GetMem(2048);
	Repeat
		Count := Stream.Read(Buffer^, 2048);
		If Count > 0 Then
			WriteLn('Got ', Count, ' bytes !');
		Stream.Write(Buffer^, Count);
	Until False;
	Stream.Free;
	FreeMem(Buffer, 2048);
	CloseHandle(Handle);
End.

(translated from a C# example)

but the handle returned is always -1

(The guid is correct as returned by openvpn)

2010/5/13 Marc Weustink :

Hello FPC-Pascal,

Thursday, May 13, 2010, 10:42:37 PM, you wrote:

JAGdFJ>         Handle := CreateFile(PChar(TAP_Device), GENERIC_READ Or
JAGdFJ> GENERIC_WRITE, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM Or
JAGdFJ> FILE_FLAG_OVERLAPPED, 0);

Try using:

Handle:=CreateFileA(PChar(TAP_Device), GENERIC_READ or GENERIC_WRITE,
                     0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);

Overlapped attribute is an error for sure as non overlapped structure is being passed. In fact I think that no FILE_xxxx is > (translated from a C# example)

Maybe the example is wrong ;)

handle still returns -1

2010/5/13 José Mejuto :

This is the C# example i found :

http://www.varsanofiev.com/inside/TunTest.cs

2010/5/13 Jorge Aldo G. de F. Junior :

Hello FPC-Pascal,

Friday, May 14, 2010, 12:14:31 AM, you wrote:

JAGdFJ> This is the C# example i found :
JAGdFJ> http://www.varsanofiev.com/inside/TunTest.cs

Also this line is wrong IMHO:

TAP_Device = '\\\\.\\Global\\{44F7688F-77FA-43DC-8D8F-9CBA23E01BB0}.tap';

it should be:

TAP_Device = '\\.\Global\{44F7688F-77FA-43DC-8D8F-9CBA23E01BB0}.tap';

Pascal does not need the slash escape sequence.

Uses
Windows,
Classes,

	BlckSock;

Const
	TAP_Device = '\\.\Global\{44F7688F-77FA-43DC-8D8F-9CBA23E01BB0}.tap'#00;
	TAP_Buffer = 8192;
Var
	Handle : Integer;
	Buffer : Pointer;
	Stream : THandleStream;
	Count  : Integer;
Begin
	Handle := CreateFileA(PChar(TAP_Device), GENERIC_READ or
GENERIC_WRITE, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
	Stream := THandleStream.Create(Handle);
	Buffer := GetMem(TAP_Buffer);
	Repeat
		Count := Stream.Read(Buffer^, TAP_Buffer);
		If Count > 0 Then
			Stream.Write(Buffer^, Count);
	Until False;
	Stream.Free;
	FreeMem(Buffer, TAP_Buffer);
	CloseHandle(Handle);
End.

=========

i am able to receive packets setting up a tap device with a fixed ip and doing ping to the gateway address...

now i need to decipher the ioctl calls...

2010/5/13 José Mejuto :

Hello FPC-Pascal,

Friday, May 14, 2010, 1:34:08 PM, you wrote:

JAGdFJ> i am able to receive packets setting up a tap device with a fixed ip
JAGdFJ> and doing ping to the gateway address...
JAGdFJ> now i need to decipher the ioctl calls...

Sorry, I can not help more, I had never used TAP and even I do not know what it is (except a brief definition in wikipedia).