ExitHandler module

[hannahfluch]

I recently came across a CTF challenge that required me to overwrite the __exit_funcs list in libc.

After doing some research I found that a lot of writeups utilize a similar class structure. As shown here.

It would be cool to have a utility class as there is for the SigreturnFrame already. This would make writing exploits that overwrite exit handlers easier and more streamlined.

When it comes to testing I would just create some ExitHandlers and check if they are properly packed / tests regarding pointer mangling.

I would be open to implementing this myself and opening a PR.