protection againts debugers or decompilers

[MOISES]

Hi,

Is there a way to protect a FWH exe against being debugged or decompiled?. I do not want to use a compresion software such as UPX, as I have tested it and it does not always work.

Makbe a function that avoid some vectors?.

[Patrick Mast]

Is there a way to protect a FWH exe against being debugged or decompiled?. I do not want to use a compresion software such as UPX, as I have tested it and it does not always work.

I use OPX all the time and did not encounter any problem so far. How does it fail for you?

Also, in your code, you can do:
#pragma TEXTHIDDEN(1)

This scrambles any text in your exe. This makes "reading" text from your sources in your exe impossible.

See this sample:

Code: Select all

//NOTEST
/*
 * $Id: tstprag.prg,v 1.2 2005/04/22 18:41:31 ptsarenko Exp $
 */

#pragma TracePragmas=On
#pragma ExitSeverity=1

/* Unknow pragmas will be ignored silently */
#pragma BadPragma=off
#pragma /Y+

function Main()

#pragma Shortcut=On
#pragma Shortcut= Off
#pragma Shortcut = On
#pragma Shortcut(OFF)
#pragma Shortcut( On)
#pragma Shortcut( OFF )
#pragma Shortcut( On )
#pragma Shortcut( OFF )
#pragma Shortcut( ON

/* or #pragma /Z+ */

  if .t. .and. .f.
    ? "Always"
  endif

  if .f. .and. .t.
    ? "Never"
  endif

#pragma /Z-
/* or #pragma Shortcut=Off */

#pragma Exitseverity=0
#pragma Exitseverity=1
#pragma Exitseverity(0)
#pragma Exitseverity( 1 )
#pragma Exitseverity( 0 )
#pragma Exitseverity= 2
#pragma Exitseverity= 1

/* Pragmas with bad values will cause an error  */
#pragma WarningLevel=8

#pragma TEXTHIDDEN(1)
? "This is a hidden text"
#pragma TEXTHIDDEN(0)

return nil

--
Sincerely,

Patrick Mast,
xHarbour.com Inc.
http://www.xHarbour.com

[MOISES]

Patrick:

Thank you for your reply. I tested http://upx.sourceforge.net/ and in some computers the program just did not run, so I decide not to use it any longer.

I am afraid I don´t understand the C example. Could you explain a little bit, please?.

Thank you.

[fraxzi]

Hi,

This may help..


I use this with UPX on FWH apps...

upx.exe your.exe --compress-exports=0


Regards