key logger/blocker/inputer

[simoyd]

I want to make my own vb program that:

1) Intercepts keystrockes (even when unfocused) and can put them into a log file or display on screen or whatever.

2) Can block keys or the entire keybored from the user

3) Can have keys inputted by the program (aka i know how to set up tcp/ip and i will be inputting it remotely)

I know this kinda just majorly sounds like a virus, but the reason I want to do this is because I have alot of computers in my house and eventhough there are alot of programs that do this out there to download (and I have used a few of them) I thought it would be fun to make my own one that i could personalize to my own needs

[Kameleon]

Search the net (Or the forum) for 'Keyboard hook'

[simoyd]

i found lots of thing concerning reading and blocking keystrokes for on the application but it wasn't global (aka all applications), and i couldn't input keystrokes using code..... if someone could post a code snippet concerning all 3 of the issues above it would be greatly appreciated

[Stiletto]

This answers your first issue:

Private Sub Form_KeyPress(KeyAscii As Integer)
If KeyAscii = vbKeyReturn Then
   MsgBox "User Pressed Enter"
   'Code Here
End If
End Sub

This is an xample on how to fnd when the user pressed a key.
The xample is about the Enter key only, but you can do it with al; keys.

[Kameleon]

Apparently, in VB, to do a keyboard hook you need to use a DLL

[Stiletto]

Or lockin all keys in the keyboard using code ...(which is damn long)

[Blacknight]

I want to buld a similiar program like simoyd, only a little diffrent:
I want a program that once u highlight text, even on the browser and press let's say ctrl+c the highlighted text will be automaticaly sent into a text box in my program. Anybody got any ideas?

[simoyd]

Originally posted by Stiletto
Or lockin all keys in the keyboard using code ...(which is damn long)

how would i do that (I have time.... and patience..)

or does anyone know where i can get a dll thing like the one stated above??

[BuggyProgrammer]

the apiguide example

'In a module
Public Const WH_KEYBOARD = 2
Public Const VK_SHIFT = &H10
Declare Function CallNextHookEx Lib "user32" (ByVal hHook As Long, ByVal ncode As Long, ByVal wParam As Long, lParam As Any) As Long
Declare Function GetKeyState Lib "user32" (ByVal nVirtKey As Long) As Integer
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
Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Long) As Long
Public hHook As Long
Public Function KeyboardProc(ByVal idHook As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
    'if idHook is less than zero, no further processing is required
    If idHook < 0 Then
        'call the next hook
        KeyboardProc = CallNextHookEx(hHook, idHook, wParam, ByVal lParam)
    Else
        'check if SHIFT-S is pressed
        If (GetKeyState(VK_SHIFT) And &HF0000000) And wParam = Asc("S") Then
            'show the result
            Form1.Print "Shift-S pressed ..."
        End If
        'call the next hook
        KeyboardProc = CallNextHookEx(hHook, idHook, wParam, ByVal lParam)
    End If
End Function
 
'In a form, called Form1
Private Sub Form_Load()
    'KPD-Team 2000
    'URL: [url]http://www.allapi.net/[/url]
    'E-Mail: [email][email protected][/email]
    'set a keyboard hook
    hHook = SetWindowsHookEx(WH_KEYBOARD, AddressOf KeyboardProc, App.hInstance, App.ThreadID)
End Sub
Private Sub Form_Unload(Cancel As Integer)
    'remove the windows-hook
    UnhookWindowsHookEx hHook
End Sub

but keyboard hooking is awkward. it tells you twice of the key you pressed.

[simoyd]

ok... i forgot to say... i used that (or a simmilar thing) to log/read the keys (the reason that it reads it 2ce is cause it reads keyup and keydown... the example i have doesn't). I have been able to read keys and input keys... but what I want to do is also be able to block those keys... any suggestions??

[BuggyProgrammer]

Originally posted by simoyd
ok... i forgot to say... i used that (or a simmilar thing) to log/read the keys (the reason that it reads it 2ce is cause it reads keyup and keydown... the example i have doesn't). I have been able to read keys and input keys... but what I want to do is also be able to block those keys... any suggestions??

ummm....... there are 4 when you press and release. 2 when you keydown and 2 when you keyup.

and to block it just make sure that if it is the key you want to block dont let it get to

KeyboardProc = CallNextHookEx(hHook, idHook, wParam, ByVal lParam)


so use an exit sub before it.

[Lord Orwell]

um he stated there are a lot of programs out that do that. well windows actually comes with one. If you use Netmeeting for remote desktop sharing, it will lock out the keyboard and mouse both of the target computer and put its desktop on yours. about the only thing you can't do with it is stream mpegs (and maybe you can do that if you have a 100mpb connection; mine was 10)

[simoyd]

i know that there many programs out there.... and to my knowlage netmeeting can't block keys......

how do i block keys?

even if netmeeting can, i would prefer to make my own

[simoyd]

^bump^

[MerrionComputin]

In Windows NT/2000/XP you can install a WH_KEYBOARD_LL hook (using the EventVB.dll) thus:

' Form declarations
Private WithEvents apiLink As EventVB.ApiFunctions
Private WithEvents hook As EventVB.EnumHandler 
 
' Form load
Private Sub Form_Load()
  Set apiLink = New EventVb.ApiFunctions
  Set hook = apiLink.EventHandlerLink
 
  hook.StartHook WH_KEYBOARD_LL,apiLink.AppModuleHandle, 0
 
End Sub
 
' Form unload
Private Sub Form_Unload(Cancel As Integer)
   hook.StopHook WH_KEYBOARD_LL
End Sub
 
Private Sub hook_HOOKPROCKEYBOARDLL(Action As EventVB.enHookCode, ByVal KeyState As Long, ByVal KeyStrokeInfo As EventVB.ApiKBDLLHOOKSTRUCT, lMsgRet As Long)
 
'\\ Prevent key being passed on....
     lMsgRet = 1
 
End Sub

HTH,
Duncan

[simoyd]

I must be stupid or something.... how do i load the dll into vb?

[simoyd]

never mind... i got it

[simoyd]

this is perfect... is there some way in order to use this to input keys as well?? (aka instead of sendkeys)

[KayJay]

to block keystrokes and mouse movements try this

Private Declare Function BlockInput Lib "user32" (ByVal fBlock As Long) As Long
Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Private Sub Command1_Click()
    DoEvents
    'block the mouse and keyboard input
    BlockInput True
    'wait 10 seconds before unblocking it
    Sleep 10000
    'unblock the mouse and keyboard input
    BlockInput False
End Sub

[simoyd]

Originally posted by MerrionComputin
In Windows NT/2000/XP you can install a WH_KEYBOARD_LL hook (using the EventVB.dll) thus:

' Form declarations
Private WithEvents apiLink As EventVB.ApiFunctions
Private WithEvents hook As EventVB.EnumHandler 
 
' Form load
Private Sub Form_Load()
  Set apiLink = New EventVb.ApiFunctions
  Set hook = apiLink.EventHandlerLink
 
  hook.StartHook WH_KEYBOARD_LL,apiLink.AppModuleHandle, 0
 
End Sub
 
' Form unload
Private Sub Form_Unload(Cancel As Integer)
   hook.StopHook WH_KEYBOARD_LL
End Sub
 
Private Sub hook_HOOKPROCKEYBOARDLL(Action As EventVB.enHookCode, ByVal KeyState As Long, ByVal KeyStrokeInfo As EventVB.ApiKBDLLHOOKSTRUCT, lMsgRet As Long)
 
'\\ Prevent key being passed on....
     lMsgRet = 1
 
End Sub

HTH,
Duncan

How the heck do i determain the key pressed by the user before i block it??

[KayJay]

And

............................aka instead of sendkeys..........

Use the SendInput API. Example: -

Const VK_H = 72
Const VK_E = 69
Const VK_L = 76
Const VK_O = 79
Const KEYEVENTF_KEYUP = &H2
Const INPUT_MOUSE = 0
Const INPUT_KEYBOARD = 1
Const INPUT_HARDWARE = 2
Private Type MOUSEINPUT
  dx As Long
  dy As Long
  mouseData As Long
  dwFlags As Long
  time As Long
  dwExtraInfo As Long
End Type
Private Type KEYBDINPUT
  wVk As Integer
  wScan As Integer
  dwFlags As Long
  time As Long
  dwExtraInfo As Long
End Type
Private Type HARDWAREINPUT
  uMsg As Long
  wParamL As Integer
  wParamH As Integer
End Type
Private Type GENERALINPUT
  dwType As Long
  xi(0 To 23) As Byte
End Type
Private Declare Function SendInput Lib "user32.dll" (ByVal nInputs As Long, pInputs As GENERALINPUT, ByVal cbSize As Long) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (pDst As Any, pSrc As Any, ByVal ByteLen As Long)
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function SetForegroundWindow Lib "user32" (ByVal hwnd As Long) As Long
 
Private Sub Command1_Click()
    Dim lHandle As Long
    lHandle = FindWindow(vbNullString, "Untitled - Notepad")
    'Set this window to the foreground
    lHandle = SetForegroundWindow(lHandle)
    SendKey VK_H
    SendKey VK_E
    SendKey VK_L
    SendKey VK_L
    SendKey VK_O
End Sub
 
Private Sub SendKey(bKey As Byte)
    Dim GInput(0 To 1) As GENERALINPUT
    Dim KInput As KEYBDINPUT
    KInput.wVk = bKey  'the key we're going to press
    KInput.dwFlags = 0 'press the key
    'copy the structure into the input array's buffer.
    GInput(0).dwType = INPUT_KEYBOARD   ' keyboard input
    CopyMemory GInput(0).xi(0), KInput, Len(KInput)
    'do the same as above, but for releasing the key
    KInput.wVk = bKey  ' the key we're going to realease
    KInput.dwFlags = KEYEVENTF_KEYUP  ' release the key
    GInput(1).dwType = INPUT_KEYBOARD  ' keyboard input
    CopyMemory GInput(1).xi(0), KInput, Len(KInput)
    'send the input now
    Call SendInput(2, GInput(0), Len(GInput(0)))
End Sub

[simoyd]

this is all 1 big loop....

i want to be able to.. using 1 thing.. not 3 different things... to get any keys beeing pressed... be able to process them.. then block/let them through... AND using the same thing... be able to send keys... because using that method.. it will call the other api and it will go in a big loop back and forth...

This is very confusing and if you don't understand what i am talking about then i'm sorry for confusing you....

Right now i need something for me to be able to block SPECIFIC KEYS....

i've pretty much got the rest of what i need... i just need something that will block specific keys and not the whole keyboard

[MerrionComputin]

To block a specific key (lets say B) modify the above snippet thus:

Private Sub hook_HOOKPROCKEYBOARDLL(Action As EventVB.enHookCode, ByVal KeyState As Long, ByVal KeyStrokeInfo As EventVB.ApiKBDLLHOOKSTRUCT, lMsgRet As Long)
 
If KeyStrokeInfo.vkCode = vbKeyB Then
'\\ Prevent key being passed on....
     lMsgRet = 1
End If
 
End Sub

HTH,
Duncan

See rather basic help documentation...

HTH,
Duncan

[simoyd]

i figured it out just before you posted it thx alot anyway... this really helps me alot... not i can do all of the stuff that i stated above !!!