How to Mask Ctrl+alt+del, ALT + TAB, and Ctrl+esc key sequences in Windows XP systems

For people who have used windows, few people are unaware of the Ctrl+alt+del key combination, especially when using a frequently frozen windows9x, which is a key combination of emergency exits specifically for system security. VC Knowledge Base Online magazine 11th, Ac952_z_cn wrote in his personal column about this article: "How to block Ctrl+alt+del under WINDOWS nt/2000." So this article focuses on how to implement the masked Ctrl+alt+del key combinations in Windows XP, Task Manager, Task toggle combination (ALT + TAB), taskbar, and Start menu (Ctrl+esc,vk_lwin,vk_rwin). This method can also be applied to Windows 2000 environments.

In Windows 9x/me systems, the key way to screen Ctrl+alt+del and various tasks is to do this in the following ways:

BOOL bOldState;
SystemParametersInfo(SPI_SETSCREENSAVERRUNNING, TRUE, &bOldState, 0);

Ms Boss thinks this method is amateur, so it was modified in Windows NT/2000/XP. In these newer versions of Windows, users log in using Winlogon and gina--graphical identification and authentication, meaning graphical identity authentication, which is pretty scary, isn't it! That's actually what happened. Winlogon is part of a Windows system that provides interactive login support, while Gina is the Msgina.dll of a dll--that Winlogon is used to implement authentication. Wlxinitialize, Wlxactivateusershell is the output, of course, I do not know these two, there are other. The former initiates its own initialization, which activates the user's shell. Windows uses this DLL to authenticate user names + passwords, but developers can use their own Gina instead of Msgina.dll. For example, the implementation of smart cards, retinal scanners, DNA testing, and so on authentication mechanism to replace the input username + password form of identity checks. All of the functions associated with Gina are listed in the table below. One of them is WlxLoggedOnSAS, and when the Ctrl+alt+del key is pressed, Winlogon calls the function.

(Table i) List of GINA functions

Function	Describe
Wlxactivateusershell	Activate user shell
Wlxdisplaylockednotice	Allow Gina DLL to display lock information
Wlxdisplaysasnotice	Winlogon calls this function when no user is logged in
Wlxdisplaystatusmessage	Winlogon Call this function to display with a state information
Wlxgetconsoleswitchcredentials	Winlogon calls this function to read the trust information of the currently logged in user and transparently upload them to the target session
Wlxgetstatusmessage	Winlogon call this function to get the current state information
Wlxinitialize	Initializes a GINA DLL for the specified window position
Wlxislockok	Verifying workstation normal lockdown
Wlxislogoffok	Verify logoff is normal
WlxLoggedOnSAS	The user has logged in and the workstation is not locked and if a SAS event is received at this time, Winlogon calls this function
WlxLoggedOutSAS	No user logged in, if the SAS event is received at this time, then Winlogon calls this function
Wlxlogoff	Notify Gina DLL when requesting logoff operation
Wlxnegotiate	Indicates whether the current Winlogon version can use the Gina DLL
Wlxnetworkproviderload	Winlogon calls this function after the network service provider has been loaded to collect identity and authentication information
Wlxremovestatusmessage	Winlogon Call this function to tell Gina DLL to stop displaying state information
Wlxscreensavernotify	Allow Gina to interact with screen saver operations
Wlxshutdown	Winlogon calls this function before shutting down, allowing Gina to implement any shutdown tasks, such as exiting the smart card from the reader
Wlxstartapplication	Call this function when the system needs to start the application in the context of the user
Wlxwkstalockedsas	When a workstation is locked and if a SAS is received, Winlogon calls this function