Simulate CTLR + ALT + DEL

[DDfunbags]

I am trying to simulate all sort of key presses, CTRL + ALT + DEL being one of them.

I have tried GetKeyboardState and SetKeyboardState to no avail. I'z prolly doing something wrong.

I am runing Win2K, if that makes a difference?

Anywayz, thanks in advance.

[Megatron]

I read somewhere that as a safety feature, Ctrl+Alt+Del will only function when hardware interrupts are sent (e.g: when the physical keys are pressed).

[filburt1]

Do any of these help?

http://www.vbforums.com/showthread.p...ate+ctrlaltdel
http://www.vbforums.com/showthread.p...ate+ctrlaltdel

[DDfunbags]

Cheerz guys.

I'll get there! I know it's possible, but just don't know how yet!!

[filburt1]

Originally posted by filburt1
Do any of these help?

http://www.vbforums.com/showthread.p...ate+ctrlaltdel
http://www.vbforums.com/showthread.p...ate+ctrlaltdel

Have you taken a peek at these?

[gxpark]

AFAIK, in WinNT platforms the only way to simulate that key combination is to create your own "Graphical Identification and Authentication" module, or GINA for short.

Don't ask me how as I have no idea, but I believe there are some examples of GINAs in the Platform SDK (although I bet they are in C++).

[chrisjk]

I don't think it's pos, certainly not in win2k. There's an option for the user to have to press CTRL+ALT+DEL to log on, change pwd etc, and it says this is a security feature because Windows will only respond to actual keystrokes

I tried

SendKeys "^%{DEL}"

on win98 and 2k, neither of which produced any joy.

[gxpark]

Originally posted by chrisjk
I don't think it's pos, certainly not in win2k. There's an option for the user to have to press CTRL+ALT+DEL to log on, change pwd etc, and it says this is a security feature because Windows will only respond to actual keystrokes

I tried

SendKeys "^%{DEL}"

on win98 and 2k, neither of which produced any joy.

Everything is possible, including this one. pcAnywhere does it so I believe us mortals can too (not very easy do).

[chrisjk]

okay, but why would MS go to the bother of implementing this CTRL+ALT+DEL "safety feature" if it could easily be simulated?

[gxpark]

Originally posted by chrisjk
okay, but why would MS go to the bother of implementing this CTRL+ALT+DEL "safety feature" if it could easily be simulated?

Remove the "easily" from your sentence, and then I'd answer, Who the hell knows?

[JoshT]

It's to guarantee that pressing Ctrl+Alt+Del before inputtung your password is done by the OS, not a Trojan horse program or something

[DDfunbags]

Yer filburt1 I looked, cheerz. Didn't get the answer tho

You can disable CTRL+ALT+DELETE, right?

[chrisjk]

You can disable CTRL+ALT+DELETE, right?

only if you're using Win9x

[DDfunbags]

Thanks a lot guys, you'z all been really helpful.

One other thing, can I disable and simulate all other keys and combinations tho? just not CTRL+ALT+DELETE

[chrisjk]

Use SendKeys

% is ALT
^ is CTRL
+ is SHIFT

SendKeys "%{ENTER}"

is ALT+ENTER

SendKeys "^%{F10}"

is CTRL+ALT+F10

[gxpark]

I wonder why people keep trying to stop users from switching to other programs

Anyway, disabling system shorcuts is only *possible* on Win9x (forget it in Win2k/XP). What you need to do is to cheat Windows telling it that the screen saver is running, this way Windows automatically disables those keys. Correct me if I'm wrong, but I believe SystemParametersInfo is the API function you need.

[Joey_k29]

The way I understand it, PC Anywhere paid a pretty penny to Microsoft to get the code they needed. I don't believe that code has been, is being, or will ever be released to the general programming public. Anyone know any employees of Symantec ? I think that is your best chance. Good Luck. If you somehow find out how, just email me at [email protected].

[Zevlag]

This is a programming community isn't it? No Net Admins? That is why VNC hasn't been mentioned! I strongly reccomend VNC as a replacement to PCAnywhere. Also it allows a CTRL+ALT+DEL to be sent, only it is installed as a service though, that might be the key. VNC can be found at http://www.uk.research.att.com/vnc/ , the SOURCE in C++ is there, if you have the patience to look through it ( or maybe email the authors) you might be able to find out what you need.

Zevlag

[Zevlag]

Here is the relevant code I could find:

// Static routine used to fool Winlogon into thinking CtrlAltDel was pressed

void *
SimulateCtrlAltDelThreadFn(void *context)
{
	HDESK old_desktop = GetThreadDesktop(GetCurrentThreadId());

	// Switch into the Winlogon desktop
	if (!vncService::SelectDesktop("Winlogon"))
	{
		log.Print(LL_INTERR, VNCLOG("failed to select logon desktop\n"));
		return FALSE;
	}

	log.Print(LL_ALL, VNCLOG("generating ctrl-alt-del\n"));

	// Fake a hotkey event to any windows we find there.... :(
	// Winlogon uses hotkeys to trap Ctrl-Alt-Del...
	PostMessage(HWND_BROADCAST, WM_HOTKEY, 0, MAKELONG(MOD_ALT | MOD_CONTROL, VK_DELETE));

	// Switch back to our original desktop
	if (old_desktop != NULL)
		vncService::SelectHDESK(old_desktop);

	return NULL;
}

// Static routine to simulate Ctrl-Alt-Del locally

BOOL
vncService::SimulateCtrlAltDel()
{
	log.Print(LL_ALL, VNCLOG("preparing to generate ctrl-alt-del\n"));

	// Are we running on NT?
	if (IsWinNT())
	{
		log.Print(LL_ALL, VNCLOG("spawn ctrl-alt-del thread...\n"));

		// *** This is an unpleasant hack.  Oh dear.

		// I simulate CtrAltDel by posting a WM_HOTKEY message to all
		// the windows on the Winlogon desktop.
		// This requires that the current thread is part of the Winlogon desktop.
		// But the current thread has hooks set & a window open, so it can't
		// switch desktops, so I instead spawn a new thread & let that do the work...

		omni_thread *thread = omni_thread::create(SimulateCtrlAltDelThreadFn);
		if (thread == NULL)
			return FALSE;
		thread->join(NULL);

		return TRUE;
	}

	return TRUE;
}

[Serge]

Here is how to disable ALT-TAB, ALT-ESC, CTRL-ESC in NT4 SP3 and higher and Win2000. (Cant get the CTRL+ALT+DEL to work though). I converted this code from C++ code that was in MSDN.

Add a checkbox control to your form

Module code

Option Explicit
Public Type KBDLLHOOKSTRUCT
    vkCode As Long
    scanCode As Long
    flags As Long
    time As Long
    dwExtraInfo As Long
End Type
Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Public Declare Function GetKeyState Lib "user32" (ByVal nVirtKey As Long) As Integer
Public Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Long, ByVal lpfn As Long, ByVal hmod As Long, ByVal dwThreadId As Long) As Long
Public Declare Function CallNextHookEx Lib "user32" (ByVal hHook As Long, ByVal nCode As Long, ByVal wParam As Long, lParam As Any) As Long
Public Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Long) As Long
Public Const HC_ACTION = 0
Public Const WM_KEYDOWN = &H100
Public Const WM_KEYUP = &H101
Public Const WM_SYSKEYDOWN = &H104
Public Const WM_SYSKEYUP = &H105
Public Const VK_TAB = &H9
Public Const VK_CONTROL = &H11
Public Const VK_ESCAPE = &H1B
Public Const VK_DELETE = &H2E
 
Public Const WH_KEYBOARD_LL = 13
Public Const LLKHF_ALTDOWN = &H20
 
 
Dim m_udtKEYBOARDHOOK As KBDLLHOOKSTRUCT
 
Public Function KeyboardProc(ByVal nCode As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
    Dim blnConsumeKey As Boolean
    
    If (nCode = HC_ACTION) Then
        If wParam = WM_KEYDOWN Or wParam = WM_SYSKEYDOWN Or wParam = WM_KEYUP Or wParam = WM_SYSKEYUP Then
            CopyMemory m_udtKEYBOARDHOOK, ByVal lParam, Len(m_udtKEYBOARDHOOK)
            With m_udtKEYBOARDHOOK
                blnConsumeKey = _
                ((.vkCode = VK_TAB) And ((.flags And LLKHF_ALTDOWN) <> 0)) Or _
                ((.vkCode = VK_ESCAPE) And ((.flags And LLKHF_ALTDOWN) <> 0)) Or _
                ((.vkCode = VK_ESCAPE) And ((GetKeyState(VK_CONTROL) And &H8000) <> 0))
            End With
        End If
    End If
    
    If blnConsumeKey Then
        KeyboardProc = -1
    Else
        KeyboardProc = CallNextHookEx(0, nCode, wParam, ByVal lParam)
    End If
End Function

Form code

Dim m_lngKeyboad As Long
 
Private Sub chkDisable_Click()
    If chkDisable = vbChecked Then
        m_lngKeyboad = SetWindowsHookEx(WH_KEYBOARD_LL, AddressOf KeyboardProc, App.hInstance, 0)
    Else
        UnhookWindowsHookEx m_lngKeyboad
        m_lngKeyboad = 0
    End If
End Sub
 
Private Sub Form_Unload(Cancel As Integer)
    If m_lngKeyboad <> 0 Then UnhookWindowsHookEx m_lngKeyboad
End Sub

Note Do not close the application while in IDE, but press X in the form's title bar. If you close it by pressing END button in IDE you wont be able to hook it again without restarting the IDE.

[gxpark]

way to go! I don't understand how the code works, but I'll surely add it to my library.

[DDfunbags]

Thanks alot guys. You've all been really helpfull.

Cheerz spec to Zevlag, I'll have a bash at figuring out that code (I know more Japanese than C ), and Serge

[Zevlag]

Well, umm, ok, your welcome

If you can't figure out what the code is doing I would recomend that you eMail the authors. I'm sure that they wouldn't mind answering your questions......


Zevlag