Connecting Windows Driver to Userland Service

Question

How do I communicate with a driver from the userland in Windows? (Vista if that makes a difference.) Can I, and how, communicate with the service from the driver site?

Answer 1

OSR online is a good source of information on writing windows drivers.

How to name devices in kernel mode (with a link to access security).

The basic path is :

Name your device object with one of the naming functions (e.g. WdfDeviceInitAssignName).

In the service you do :

hDev = CreateFile( , ..., OVERLAPPED )

DeviceIOControl( hDev, .. , OVERLAPPED);

while( !end )
   SleepEx( 100, true /*bAltertable*/ );

...

In the driver, you have an IRP queue, in which you queue requests from the service. When you want to call the service, you complete one of the IRPs.

NB: Its a bit complex ... and depends on the driver framework/model you are working with. I had to do this only once with in a NDIS filter driver. Ask again, if you need more info.