Disabling the keyboard in windows c++?

Question

How can I completely disable the keyboard using c++ in windows? And by completely disable I mean so even Ctrl+Alt+Delete doesn't work. I did consider using a keyboard driver but I think you need to restart the computer after it is installed, but since I only need to disable it for a couple minutes that wouldn't really work.

Answer 1

This is not really possible.

WinLogon is designed as the one process that intercepts the Ctrl+Alt+Del key press, even when all other things hang or die. This is the failsafe against malicious sessions, etc. So there is no obvious workaround.

Maybe a keyboard filter driver would make your request possible, but that is a real kernel-driver.

Answer 2

You can't disable Ctrl-Alt-Delete without removing the keyboard or replacing the keyboard driver, it generates a kernel level notification.

Answer 3

You could install a keyboard hook and filter out the messages, but you might need to have your application as the top most window. Even then Ctrl+Alt+Del would not get filtered out.

Here's SetWindowsHookEx on MSDN

Example of Hooking the Keyboard

Answer 4

You could use BlockInput function. But it doesn't block CTRL + ALT + DEL.

Answer 5

Ok, here goes several random suggestions. I don't have a definitite answer, but here's where I would start:

1) SetupDiRemoveDevice is probably the API you want to call. Although to call it, you'll need to make a lot of other device enumeration calls. Enumerate your HID and USB devices and find the keyboard. Start by looking for the VID/PID of the actual device for starters.

2) Delete the drivers kdbclass.sys and kbdhid.sys. You'll be fighting Windows system file to do this. I have no idea if this will work, but sounds interesting and simple.

3) Write a USB filter driver. Your driver will need to know (or be passed) the vid/pid of the device to filter on, but it might work.