hi all.

 

before reading Excuse me for my poor English.

 

 

i want to detect if my program opened with a Debuger in Delphi.

 

i found a few code in other website ,but thats not work true!

 

please help me.

http://msdn.microsoft.com/en-us/library/ms680345%28VS.85%29.aspx

search for anti-debugging techniques in the forum, you will get your answer.

Edited March 10, 201312 yr by Kingstaa

@ Sam7sam7

specifically write your problem in detail and with the attached file for testing

thank you for help

 

I used the "IsDebuggerPresent" function in  my app  but this not work in OllyDbg!!!

 

 

my problem solved with this function

procedure AntiDebug;

var

  bISDebug: Boolean;

begin

  bISDebug := True;

  try

    asm

      INT 2Dh

      nop

    end;

  except

    bISDebug := False;

  end;

  if  bISDebug then

    TerminateProcess(GetCurrentProcess, 0)

end;

Edited March 13, 201312 yr by Sam7sam7

This simple debugger detection can be killed with a simple one byte patch...

Its really easy to bypass this...

This simple debugger detection can be killed with a simple one byte patch...

Its really easy to bypass this...

can you give me a better way ?

Sam7sam7 you can convert this for c++?

 

Using:

 

bool Example()

{

__asm{

      INT 2Dh

      nop

 

}

}

Sam7sam7 you can convert this for c++?

 

Using:

 

bool Example()

{

__asm{

      INT 2Dh

      nop

 

}

}

I wrote the following function in delphi but when i open my app in ollydbg can't detect it!!

{ -------------------------------------------------------------------------------  + Function : Int2D_DBG  + DateTime  : 2013.03.28  + Result    : Bool  ------------------------------------------------------------------------------- }Function Int2D_DBG(): Bool;{ Exception Based Anti-Debugging }ASM  mov Result,$0 // Return False@@_TRY :  pushad  mov esi, offset @@_Handler  push esi  push    FS:[0]  mov     FS:[0], ESP  // ---------------------  int     2Dh  nop  // ---------------------@@_EXCEPT:  mov Result,$1  // Return True  jmp @@_NoException@@_Handler:  mov esp, [esp + 8]  pop dword ptr fs:[0]  add esp, 4  popad@@_TRY_END :  jmp @@_ExceptionHandled@@_NoException:  pop dword ptr fs:[0]  add esp, 32 + 4@@_ExceptionHandled:End;

example of use :

  if Int2D_DBG = True then    ShowMessage('IS DBG')  else    ShowMessage('Is not DBG');

Edited November 28, 201311 yr by Sam7sam7