IOCTL Communication to Kbfiltr from user-app

NTDEV
1

Hi,

I am using kbfiltr sample code from DDK.
I have used IOregisterdeviceinterface using a GUID in the kbfiltr and then trying to get a handle using createfile from application.

When I used file_read_access, I am getting access error code (5).

Can anyone tell me how to communicate to kbfiltr from user application.

Regards,
J. Joshua David

2

Yes, use the KMDF version of kbfiltr which exposes a raw PDO. You cannot ask for read access on the kbfiltr filter device object b/c kbdclass sits on top of your driver and enforces exclusive read access for the raw input thread. Even if you don’t ask for read access and just send IOCTLs, that will not work either b/c kbdclass does not pass unknown IOCTLs down the stack, they are failed immediately. The raw PDO fixes both issues. You can use reads and custom IOCTLs to it and then you can fwd them directly to the filter device object or just complete them in the PDO based on events in the filter.

d

-----Original Message-----
From: xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of xxxxx@gmail.com
Sent: Thursday, December 06, 2007 11:04 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] IOCTL Communication to Kbfiltr from user-app

Hi,

I am using kbfiltr sample code from DDK.
I have used IOregisterdeviceinterface using a GUID in the kbfiltr and then trying to get a handle using createfile from application.

When I used file_read_access, I am getting access error code (5).

Can anyone tell me how to communicate to kbfiltr from user application.

Regards,
J. Joshua David

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3

Hi,

I am using DDK version and I am not familiar with KMDF version.

Can someone help me in the following.

I followed " How to commuicate to filters" from Microsoft webpage. I created control code from pnp and named it with Dos Device name.

I have IRP_MJ_DEVICE_CONTROL function and IRP_MJ_CREATE function seperately.

I tried to create a handle from user application, I am not able to do that.
How to open handle from user app ?

Regards,
J. Joshua David

4

You should be using the KMDF version, get the WDK and take a look at it.

–
Don Burn (MVP, Windows DDK)
Windows 2k/XP/2k3 Filesystem and Driver Consulting
Website: http://www.windrvr.com
Blog: http://msmvps.com/blogs/WinDrvr
Remove StopSpam to reply

wrote in message news:xxxxx@ntdev…
> Hi,
>
> I am using DDK version and I am not familiar with KMDF version.
>
> Can someone help me in the following.
>
> I followed " How to commuicate to filters" from Microsoft webpage. I
> created control code from pnp and named it with Dos Device name.
>
> I have IRP_MJ_DEVICE_CONTROL function and IRP_MJ_CREATE function
> seperately.
>
> I tried to create a handle from user application, I am not able to do
> that.
> How to open handle from user app ?
>
> Regards,
> J. Joshua David
>