How to start or simulate keyboard interrupt?

Question

I am writing a keyboard filter filter driver for Windows and I need to insert my user keystroke data into the Windows message queue. I managed to capture all the keys that the OnReadCompletion () function was pressed on, the feedback from IoSetCompletionRoutine () in my Read () function for my driver as follows:

NTSTATUS Read(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp)
{
    PDEVICE_EXTENSION deviceExtension = DeviceObject->DeviceExtension;

    IoCopyCurrentIrpStackLocationToNext(Irp);
    IoSetCompletionRoutine(Irp, OnReadCompletion, DeviceObject, TRUE, TRUE, TRUE);
    return IoCallDriver (deviceExtension->pKeyboardDevice, Irp);
}

NTSTATUS OnReadCompletion(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp, IN PVOID Context)
{
// ...
}

This filter driver is connected to the kbdclass driver as follows:

NTSTATUS DriverEntry(IN PDRIVER_OBJECT DriverObject, IN PUNICODE_STRING RegistryPath)
{
// ...
CCHAR ntNameBuffer[64] = "\\Device\\KeyboardClass0";
status = IoAttachDevice(deviceObject, &uKeyboardDeviceName, &DeviceExtension->pKeyboardDevice);
// ...

}

So, I can catch all the keys pressed in OnReadCompletion (). But I need to insert my own information into the message flow from the keyboard. Here are two issues with this:

• OnReadCompletion() . - , . ? ? (0x60 0x64) WRITE_PORT_UCHAR(), .

• IRP OnReadCompletion(), , , , . - , ?

  NTSTATUS OnReadCompletion(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp, IN PVOID Context)
  {
      PIO_STACK_LOCATION IrpStackLocation = NULL;
      INT BufferLength;
      INT numKeys = 0, i = 0;
      PDEVICE_EXTENSION deviceExtension = DeviceObject->DeviceExtension;
  
      IrpStackLocation = IoGetCurrentIrpStackLocation(Irp);
      BufferLength = IrpStackLocation->Parameters.Read.Length;
  
      if(Irp->IoStatus.Status == STATUS_SUCCESS)
      {
          PCHAR newSystemBuffer, oldSystemBuffer;
          PKEYBOARD_INPUT_DATA keys = (PKEYBOARD_INPUT_DATA)Irp->AssociatedIrp.SystemBuffer;
          numKeys = Irp->IoStatus.Information / sizeof(KEYBOARD_INPUT_DATA);
          for(i = 0; i < numKeys; i++)
          {
                   // here we print whatever was pressed
                   DbgPrint("%s -- ScanCode: %x\n", __FUNCTION__, keys[i].MakeCode);
          }
          // allocate new buffer twice as big as original
          newSystemBuffer = ExAllocatePool(NonPagedPool, Irp->IoStatus.Information * 2);
          // copy existing buffer twice into new buffer
              RtlCopyMemory(newSystemBuffer, keys, Irp->IoStatus.Information);
          RtlCopyMemory(newSystemBuffer + Irp->IoStatus.Information, keys, Irp->IoStatus.Information);
              // assign new buffer to Irp->AssociatedIrp.SystemBuffer
          oldSystemBuffer = Irp->AssociatedIrp.SystemBuffer;
          Irp->AssociatedIrp.SystemBuffer = newSystemBuffer;
              // tell IRP that we now have twice as much data
          Irp->IoStatus.Information *= 2;
          // free the old buffer
              ExFreePool(oldSystemBuffer);
      }
  
      if(Irp->PendingReturned)
          IoMarkIrpPending(Irp);
  
      return Irp->IoStatus.Status;
  }
  

, , "", , , . . !

Answer 1

, , , :

1) IRP kbdclass , IRP, . IRP, , , .

2) , - . kbdclass .

3) , MSDN- kbfiltr.

4) , - . kbdclass .

, , .