Disabling the keyboard in windows c++? - c++

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.

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.

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

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

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

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.

Related

Systemwide USB keyboard hook

im looking into the WDK at the moment to see how i would be able to make a systemwide keyboard hook on USB keyboards ( and a specific ID ).
What i want to be able to is to filter the keystrokes coming in from that specific USB keyboard (USB HID/keyboard), and be able to send that to a specific application/process only.
Ive seen examples of applications that has to be running that can do that in combination of rawinput and a hook, but i would like it to be systemwide and not demanding an application to run.
I can find examples that makes it quite easy to do with a PS2 keyboard, but when it comes to the USB it starts to look very different.
anyone could suggest me the correct model it has to be based on, and even better examples of how it would be possible to do that ?
and something that would work from XP/windows7 to Windows10 also.

Controlling Firefox from C++

I am running Mozilla Firefox on Windows 7 and would like to be able to send simple commands (New Tab, Minimize, Close Tab) to it from a C++ program.
The usual question of inter-process communication, when both processes are a part of the same user program, seems to be answered by Boost.Interprocess.
But what about actually controlling the GUI window of an entirely independent application (Mozilla)?
You can use Spy++ to debug what messages each action will produce, then replicate those messages in your program.
You can use Ranorex http://www.ranorex.com, Quick Test Pro http://www8.hp.com/us/en/software-solutions/unified-functional-testing-automation/index.html#.UpvC8OJO7tw
Will give you this ability
The general answer to controlling any Windows program through its user interface is by sending it Windows messages. There are also some rather specific Windows APIs that allow you to send specific kinds of inputs directly to the keyboard, mouse or other input device.
Assuming simple requirements, you should be able to control Firefox by sending it some combination of the messages WM_[SYS]KEY[DOWN|UP], WM_[L|R]BUTTON[DOWN|UP] or similar. You may also need to use FindWindow and other things to find where to send messages. And liberal use of Spy++ to figure out what to send and where to.
Actually, what I would do is start with AutoHotKey. It can do all this stuff and then some, and it has a massive community. It's GPL so you can find out how it does stuff and there are people there to ask for help.

Prevent other windows from "overriding" hotkeys with the windowsAPI

I'm trying to learn the basics of the windows API by making a program that, when the PRINTSCREEN button is pressed, will save a .jpeg and instantly upload it to imgur. Currently, while I'm playing most games or just browsing the desktop, this program works fine.
Some games, however, seem to block my ability to use this hotkey. (Dark Souls 2 specifically does this.) I currently use
RegisterHotKey(NULL, 1, 0, VK_SNAPSHOT)
to assign the button to my program. However, when some games are running, neither the above RegisterHotKey nor the below GetAsyncKeyState work when the key is pressed.
GetAsyncKeyState(VK_SNAPSHOT)
(I don't want to use GetAsyncKeyState due to the fact that it will keep bugging the windows API and make the program unnecessarily slow, it was just for test.)
Does anyone know of a way to stop this from happening?
(and, on an unrelated note: If it is a simple task, how would I take a screenshot spanning multiple monitor(s)? Mine currently works on only my primary monitor...)
If the application is using raw input for its keyboard mapping, then the keyboard processing code bypasses the hotkey checker. I personally have no idea if Dark Souls does this or not, but I am familiar with the Windows kernel code that does keyboard processing.

Low level keyboard hook doesn't work for a specific device in a specific app

I have coded up a low level keyboard hook using SetWindowsHookEX() on Windows CE 4.2 and it seems to work just fine. I am able to see key events using the keyboard and a barcode scanner in notepad and other applications as desired, but I do not see the barcode scanner events in the one application that I want to collect the keys in. I still see events from the keyboard, however, so I know that the keyboard hook is still working and in the hook chain. I have even tried inserting my hook in the chain every millisecond just to see if it would make a difference, but no dice. If I flip back to notepad, it's back to working the way I want it.
I'm not sure what the other application is doing to gain control of the scanner when that application is active that prevents it from acting like a keyboard any more. Any thoughts on this would be greatly appreciated. I've done a bunch of searches without any success. I looked into trying to use RAWINPUT, but it doesn't seem to be supported in Windows CE 4.2 from what I can tell as I don't see the user32.dll in the SDK.
There are two ways to get barcode data on most WEC devices.
The keyboard wedge (where data comes in as as keyboard events)
An OEM specific barcode reader API
If this other app your looking at uses option #2 then there is no keyboard data to retrieve, so it makes sense you wouldn't see any. That said, you might read this article to see if it offers any tips for your keyboard hook.
Functions exported by user32.dll in big Windows are generally found in coredll.dll in WEC/WEH.
-PaulH

Low level programmatic keyboard emulation

I bought a physical button and hooked it up to my computer, using the Arduino it communicates over USB serial to a C++ program I'm writing. Now I want to make the button simulate a keypress on my computer so I could use it as an alternative controller for the games I play.
If you are not familiar with Arduino, don't mind it, my problem lies completely in C++
The solution for this is pretty simple, it basically boils down to using SendMessage to a window with keystrokes, or many alternative methods like sendKeys and what not.
I have tried every single library or windows function that could handle something like this, but none of them actually simulates a keystroke being pressed by a keyboard.
Everything I tried so far has worked in many programs like Notepad and Chrome but none works with a game that doesn't listen to windows messages to handle key input.
My guess is that these games use GetAsyncKeyState which is communicating with the physical keyboard in a direct manner.
How could I resolve this? What API provides such functionality?
I need something very low level here, maybe even a program that emulates a new keyboard so windows thinks I have plugged in a physical one.
This would help me ALOT I've encountered this problem numerous times and I will keep encountering it in the near future with other projects.
I hope someone can help,
Thanks!
Use keybd_event() or SendInput()