Hello
I'm having some problems implementing AES's SubBytes routine. Instead of using tables id like to do it myself.
I can do the affine transformation fine, I'm just not sure how to go about getting the inverse that I need for it. The AES spec explains multiplication but I didn't notice anything about division, so I guess that means doing it with the Extended Euclidean Algorithm is out.
Is there a easy and efficient way to go about this, without tables?
Thanks