Hacksar

You may be paranoid about somebody else using your computer, and so to combat that, you just Switch Users and leave your computer on the log in screen. Also, you may have it set to go back to the log in screen once the screen saver kicks in, just for those times you forgot to log out. While this may be useful most of the times, it may not always cut it. What if you’re running some sort of intense process (like video encoding/conversion, for example) that you don’t necessarily need to interact with, but you just need to see how far it has progressed? Logging in every time you want to check that is a waste of time and energy, as, since the computer is busy with whatever it is processing, the login will be extremely slow and laggy.

On the other hand, if you simply don’t like the interface of the Window’s login screen (for some reason), or simply can’t access it easily, then this solution might be for you. My computer suddenly decided to stop letting me log out or even shut down the computer through regular means, so I had to resort to finding my own solutions. (It just freezes on the “Windows is shutting down” blue screen, if anybody has any idea why it may do these, leave a comment.)

I came across another AutoHotKey script that locks your computer with a password after either a certain amount of time, or if you give it the lock command. By lock, what it does is it places a white transparent cover over your whole screen and has an “Input Password” box in the middle. The AutoHotKey source is at the bottom of this post. For more information about how to use AutoHotKey, read the previous post on How to Control iTunes Remotely. Keep reading for the guide on how to use this computer locking script.

1. Visit the AutoHotKey website and download the latest version, and install it (if it is not already installed on your system).
2. Once installed, open up a new text document (NotePad works perfectly) and copy/paste the code given at the end of this post into the document.
3. Save the file with the extension of .ahk (deleting the .txt, if it’s there). So, for example, your file may be called “autolock.ahk”.
4. Confirm that it is working by double clicking on itunes.ahk (or whatever you named your script), and you should see a lock icon appear in the taskbar.
5. If it is running for the first time, it will ask you to set your password.
6. If you want to add the AHK script to run on startup (so that you don’t have to manually load it every time you turn on your computer), right click on your .ahk file, and go to Create Shortcut.
7. Assuming you are running Windows XP, place the shortcut you just created here: “C:\Documents and Settings\<User>\Start Menu\Programs\Startup”. For future reference, any shortcut you place here will automatically load upon startup. You can place as many shortcuts as you want, but just remember that your startup time will slow down depending on how many programs you have running on startup.
8. You are good to go! Check out the available hotkeys that you can use for AutoLock below. These are there just so that you don’t get locked out of your own computer if you forget your password. Most people will be deterred by the “Input Password” box alone, and probably won’t try different key combinations (and accidentally stumble across these). You can now successfully lock your computer while seeing how far a process might be, like ripping a DVD, etc, and not have to log in. If you want to minimize all windows when it locks (just so that if you leave anything with sensitive information open by mistake, it will be hidden when the computer locks), find the line entitled “Minimize all windows” in the code below, and remove the semicolon from the line below. So, the line that no longer has a semicolon should be the “Send #d” line.

• Alt L = Lock Screen
• Alt X = Unlock Screen
• Alt R = Reset Password
• Alt Q = Quit

;————————-Instructions————————-
;
;Alt L = Lock Screen
;Alt X = Unlock Screen
;Alt R = Reset Password
;Alt Q = Quit Program
;
;Use right click menu to set other options
;
;————————Requirements———————–
;
;Only tested on Windows XP
;
;Reasonably current version of Autohotkey
;
;———————————————————————

lockstate=0

;Creates Black Password on first run

IfNotExist, %homeDrive%\lock
FileAppend,
(
[Password]
Password=
), %homeDrive%\lock

;Creates GUI for Changing Password

Gui, Add, Text, x6 y10 w180 h20, Set your Password below-
Gui, Add, Text, x6 y40 w180 h20 , Old Password
Gui, Add, Edit, x6 y60 w180 h20 vpass0,
Gui, Add, Text, x6 y90 w180 h20, New Password
Gui, Add, Edit, x6 y110 w180 h20 vpass1,
Gui, Add, Text, x6 y140 w180 h20 , Confirm New Password
Gui, Add, Edit, x6 y160 w180 h20 vpass2,
Gui, Add, Button, x86 y190 w100 h30 gConfirm, Confirm

;checks idle time every minutes
SetTimer, Timer, 60000

;Timer Starts off disabled

IfNotExist, %homeDrive%\lock
IniWrite, 0, %homeDrive%\lock, autoactivate, Status

IfNotExist, %homeDrive%\lock
IniWrite, 900000, %homeDrive%\lock, autoactivate, milliSeconds

;Creates Menu’s

Menu, Tray, Icon , %SystemRoot%\system32\SHELL32.dll, 48
Menu, Tray, NoStandard
Menu, TimerOptions, add, 3 Hours, Hours
Menu, TimerOptions, add, 2 Hours, Hours

Minutes=60

Loop,12
{
Menu, TimerOptions, add, %Minutes% mins, Minutes
Minutes-=5
}

;Checks/Enables/Disables menu items based on status of timer

IniRead, ms, %homeDrive%\lock, autoactivate, milliSeconds

SetFormat, Float, 0.0
mins:=ms/60000

If mins > 3
Menu, TimerOptions,Check, %mins% mins

If mins = 3
Menu, TimerOptions,Check, 3 Hours

If mins = 2
Menu, TimerOptions,Check, 2 Hours

Menu, Tray, add, Lock
Menu, Tray, Default, Lock
Menu, Tray, add, Change Password, PassChange
Menu, TimerOptions, add, Disable
Menu, Tray, add, Auto-Activate, :TimerOptions

IniRead, autoStatus, %homeDrive%\lock, autoactivate, Status, 0

If autoStatus=1
SetTimer, Timer, on

If autoStatus=0
{
SetTimer, Timer, off
Menu, TimerOptions, Disable, 3 Hours
Menu, TimerOptions, Disable, 2 Hours
Minutes=60
Loop,12
{
Menu, TimerOptions, Disable, %Minutes% mins
Minutes-=5
}
Menu, TimerOptions,Rename, Disable, Enable
}

Menu, Tray, add, Exit

;Enables All Blocked Keys

Hotkey, Left, Off
Hotkey, Right, Off
Hotkey, up, Off
Hotkey, down, Off

Hotkey, Tab, Off
Hotkey, !Tab, Off
Hotkey, !F4, Off
Hotkey, LWin, Off
Hotkey, RWin, Off
Hotkey, AppsKey, Off
Hotkey, ^Escape, Off

Hotkey, NumpadUp, Off
Hotkey, NumpadDown, Off
Hotkey, NumpadLeft, Off
Hotkey, NumpadRight, Off

;If password isn’t set then you will be prompted for it on startup

IniRead, Password, %homeDrive%\lock, Password, Password

If Password=Error
IniWrite, `n, %homeDrive%\lock, Password, Password

If Password=
Gosub, SetPassword
Return

PassChange:
Gosub, SetPassword
Return

;——————————————————————-

;Disables/Enables Menu items and Timer

Disable:

If A_ThisMenuItem=Disable
{
IniWrite, 0, %homeDrive%\lock, autoactivate, Status
SetTimer, Timer, off
Menu, TimerOptions,Rename, Disable, Enable
Menu, TimerOptions, Disable, 3 Hours
Menu, TimerOptions, Disable, 2 Hours
Minutes=60
Loop,12
{
Menu, TimerOptions, Disable, %Minutes% mins
Minutes-=5
}
}

If A_ThisMenuItem=Enable
{
IniWrite, 1, %homeDrive%\lock, autoactivate, Status
SetTimer, Timer, on
Menu, TimerOptions,Rename, Enable, Disable

Menu, TimerOptions, Enable, 3 Hours
Menu, TimerOptions, Enable, 2 Hours
Minutes=60
Loop,12
{
Menu, TimerOptions, Enable, %Minutes% mins
Minutes-=5
}
}

Auto-Activate:
Return

Hours:
Minutes:

Menu, TimerOptions, UnCheck, 3 Hours
Menu, TimerOptions, UnCheck, 2 Hours
Minutes=60
Loop,12
{
Menu, TimerOptions, UnCheck, %Minutes% mins
Minutes-=5
}

Menu, TimerOptions,ToggleCheck, %A_ThisMenuItem%
StringLeft, mins,A_ThisMenuItem, 2

;Calculates milliseconds to wait based on timer option chosen

If mins=2
milliSeconds=7200000
If mins=3
milliSeconds=10800000
milliSeconds:=mins*60000
IniWrite, %milliSeconds%, %homeDrive%\lock, autoactivate, milliSeconds
Return

Timer:

;If more than X minutes has passed then lock the screen

IniRead, milliSeconds, %homeDrive%\lock, autoactivate, milliSeconds
If A_TimeIdlePhysical > %milliSeconds%
{
SetTimer, Timer, off
Gosub, Lock
}
Return

Lock:

lockstate=1

;Minimize all windows
;Send #d

IniRead, Password, %homeDrive%\lock, Password, Password

If Password=Error
IniWrite, `n, %homeDrive%\lock, Password, Password

If Password=
{
Gosub, SetPassword
Return
}

;Blocks all hotkeys which could be used to unlock the screen

Hotkey, Left, On
Hotkey, Right, On
Hotkey, up, On
Hotkey, down, On

Hotkey, Tab, On
Hotkey, !Tab, On
Hotkey, !F4, On
Hotkey, LWin, On
Hotkey, RWin, On
Hotkey, AppsKey, On
Hotkey, ^Escape, On

Hotkey, NumpadUp, On
Hotkey, NumpadDown, On
Hotkey, NumpadLeft, On
Hotkey, NumpadRight, On

WinHide, ahk_class Shell_TrayWnd

WinGetPos, , , Width, Height, ahk_class Progman

SplashTextOn, %Width%, %Height%, Lock SCREEN, SCREEN is locked
WinSet, Transparent, 100, Lock SCREEN

;——————————————————————

;Begins Locking of Screen

beginning:

lockstate=1

SetTimer, InputOnTop, 500
SetTimer, CloseTaskmgr, 600

InputBox, Password, Enter Password Below, , hide ,250,100

If ErrorLevel <> 0
{
Gosub, beginning
}
Else
{
IniRead, encryptedpass, %homeDrive%\lock, Password, Password

If (Password = RC4(encryptedpass,RC4Pass))
{
SplashTextOff
WinShow, ahk_class Shell_TrayWnd
Reload
}
Else
{
;System Modal    = 4096
;Icon Hand         = 16
;OK      =0
Timeout=5
SetTimer, DisableOK, 100
SetTimer, MsgBoxTimeout, 1000
MsgBox, 4112, Error (%Timeout%), Invalid Password, 6
Gosub, beginning
}
}
Return

CloseTaskmgr:
SetTimer, CloseTaskmgr, off
Process, Wait, taskmgr.exe, 4
Process, Close, taskmgr.exe
SetTimer, CloseTaskmgr, on
return

DisableOK:
Control, Disable, , OK, Error (%Timeout%)
Return

InputOnTop:
Control, Disable, , Cancel, Enter Password Below
WinSet, AlwaysOnTop, On, Enter Password Below
SetTimer, InputOnTop, Off
Return

MsgBoxTimeout:
oldTimeout=%Timeout%
Timeout-=1
WinSetTitle, Error (%oldTimeout%), , Error (%Timeout%)
If Timeout = 0
SetTimer, MsgBoxTimeout, off
Return

!x::
SplashTextOff
WinShow, ahk_class Shell_TrayWnd
Reload

Exit:
WinShow, ahk_class Shell_TrayWnd
ExitApp

!r::
MsgBox,4,, Are you sure you want to reset the Password?
FileDelete, %homeDrive%\lock
Return

!l::

Listvars
Winwait, %A_ScriptFullPath%
Winhide, %A_ScriptFullPath%
SetTitleMatchMode, Fast

if lockstate=0
goto, lock
WinShow, ahk_class Shell_TrayWnd
Reload

Left::
right::
up::
down::

Tab::
!Tab::
!F4::
LWin::
RWin::
Appskey::
^Escape::

NumpadUp::
NumpadDown::
NumpadLeft::
NumpadRight::

Return

SetPassword:
IniRead, Password, %homeDrive%\lock, Password, Password
Gui, Show, x361 y359 h230 w198, Change Password
If Password=
Control, Disable, ,Edit1, Change Password
Return

Confirm:
Gui, Submit
IniWrite, 0, %homeDrive%\lock, SetPassword, True
IniRead, encryptedpass, %homeDrive%\lock, Password, Password

If (RC4(encryptedpass,RC4Pass) != pass0)
{
Gui, Show
MsgBox, Old Password is incorrect
Return
}
If (pass1=”" or pass2 =”")
{
Gui, Show
MsgBox, new Password cannot be blank
Return
}
If pass1=%pass2%
{
encryptedpass:=RC4(pass1,RC4Pass)
IniWrite, %encryptedpass%, %homeDrive%\lock, Password, Password
}
Else
{
Gui, Show
MsgBox, Passwords do not match!
Return
}
Return

;___RC4 Encryption by Rajat_____________________________________

RC4(RC4Data,RC4Pass)
{
global RC4Result
ATrim = %A_AutoTrim%
AutoTrim, Off
BLines = %A_BatchLines%
SetBatchLines, -1
StringLen, RC4PassLen, RC4Pass
Loop, 256
{
a := A_Index – 1
Transform, ModVal, Mod, %a%, %RC4PassLen%
ModVal ++
StringMid, C, RC4Pass, %ModVal%, 1
Transform, AscVar, Asc, %C%
Key%a% = %AscVar%
sBox%a% = %a%
}
b = 0
Loop, 256
{
a := A_Index – 1
TempVar := b + sBox%a% + Key%a%
Transform, b, Mod, %TempVar%, 256
T := sBox%a%
sBox%a% := sBox%b%
sBox%b% = %T%
}
StringLen, DataLen, RC4Data
RC4Result =
i = 0
j = 0
Loop, %DataLen%
{
TmpVar := i + 1
Transform, i, Mod, %TmpVar%, 256
TmpVar := sBox%i% + j
Transform, j, Mod, %TmpVar%, 256
TmpVar := sBox%i% + sBox%j%
Transform, TmpVar2, Mod, %TmpVar%, 256
k := sBox%TmpVar2%
StringMid, TmpVar, RC4Data, %A_Index%, 1
Transform, AscVar, Asc, %TmpVar%
Transform, C, BitXOr, %AscVar%, %k%
IfEqual, C, 0
C = %k%
Transform, ChrVar, Chr, %C%
RC4Result = %RC4Result%%ChrVar%
}
AutoTrim, %ATrim%
SetBatchLines, %BLines%
Return RC4Result
}
;___RC4 Encryption by Rajat_

Note: I did not write this script, I found it on a forum a long time ago. I do not claim to be the author, and if I could find the source, I would link to it. If anybody knows the source of this, please leave the link as a comment and I’ll be sure to credit the proper source.

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