Quote:
Originally Posted by TheDarkWraith
You want the patcher to be able to inject code into an active process? I wrote a piece of software than can do that already. But you want that functionality included in the patcher?
Let me ask you this: why inject code into an active process when you can take it's .exe or .dll file, add a section or multiple new sections to it, dump your code into the new section (or sections) in the file, and let the Windows loader do the loading for you?
If the process is already active (loaded) and you don't have access to the .exe or .dll files then code injection is necessary if one wants to add anything new to it.
Looking at GPxPatch I wouldn't like that you have to launch the app wanting to patch from the patch app itself. There's no reason to do this. You can easily get a list of all active processes from Windows and 'attach' to any of them very easily.
The patcher has been morphing into something I've been wanting to do for a long time: take an active process and grab all of it's in memory data. Since the PE header is in the process's memory one can theoretically read this PE header and construct an .exe or .dll from the memory read in (a reverse Windows loader). For self-modifying exes this would be one way to 'capture' the image of it in it's modified state thus removing the obfuscation. That's the theory anyway. I'm slowly making my way to see if this theory is correct or not 
I can dump memory from any active process, modify it, and inject it back in and the process has no idea anything happened. The patcher is heading in that direction as another way to patch.
I've been really ambitious lately and have been trying to modify the sections already defined in an .exe or .dll file. The new version of the patcher allows you to add new sections. These sections are added to the end of the .exe or .dll file. That's cool and all but I want to be able to extend sections already defined  The problem with extending sections already defined is relocations, fix-ups, and the likes. While not an impossible task to do it's not for the faint of heart. I'm learning about relocations, fix-ups, and all the other things I need to know to be able to pull this off. I've searched for tools that already do this and haven't found any. When I've posed this question in some forums the response back was impossible or you need the source code...well I always love to prove that nothing is impossible  |
it sounds very challengig!
I was asking if it was possible to inject code in the active process rather than modifying its files for two main reasons:
- out of curiosity;
- because I think it would be a cleaner approach than modifing the executable: the lesser common users deal with it, the lesser they risk to screw up things;
Anyway, if code injection demonstrated to be a valid approach, my next question was going to be:
- would your patcher allow us to change the injected code on the fly, while the game is running, i.e. enabling/disabling patches, changing some fixed parameters, etc?