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 Forums >>  Target Specific - General  >>  How to BP "on text changed"?

Topic created on: August 25, 2011 09:25 CDT by oxident .

I'm trying to reverse an application which checks if an entered string is valid (somehow like a serial checking routine). But in my case, there isn't a simple string like "wrong password": The application just changes the color of the entered string to either black (string ok) or red (string invalid).

Now I just have any clue on where to put a BP in order to find the "code area" where the decision is taken.

The only relevant call I've found so far is GDI32.SetTextColor ... but I'm not able to track this call down to the main executable code.

I'm talking about an unpacked Win32 application, originally written in Delphi.

Thanks for any help!

  NirIzr     September 17, 2011 09:53.40 CDT
perhaps its using TextOut@GDI32?

Also, why wont you try finding the api the app uses to read the text content to begin with? such as GetWindowText etc..

  beenu     September 22, 2011 08:07.30 CDT
that's a good suggestion, parse the PE file and hook to the API. Thanks Padrim great tool pydbg, can save a lot of time.

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