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TLS Callbacks (2012)
Unfortunately, our lives as reverse engineers is not always easy. If all it took to patch an app was a deleted resource or a quick patch, a lot more people would do it.
Sometimes we must get a little ‘low-level’, wallow around in the operating system files, single-step an exception handler, or reverse engineer an unknown packer. You may see this behavior empirically when you load a binary into Olly and the program immediately terminates, without ever touching any code in the actual main module. I will use RadASM to create a binary that does nothing but call our own callback, displaying a goodboy or badboy depending on if we’re being debugged or not (though this won’t work if you are using a plugin that hides Olly).
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