Re: AES operation order
Available news archives: comp.lang.tcl - comp.lang.python - comp.security.firewalls - sci.crypt - comp.lang.php - comp.lang.javascript
Google
 
Web news.hping.org


sci.crypt archive

Re: AES operation order

From: Cryptic <no@spam.please>
Date: Mon Dec 26 2005 - 23:32:54 CET



Sebastian Gottschalk wrote:



> I still wonder why you even assumed that '*' is distributive over XOR


> in any non-trivial field like GF(2^8).



To end this uncertainity:



 for(int i = 0; i < 256; ++i)


  for(int j = 0; j < 256; ++j)


   for(int k = 0; k < 256; ++k)


    if (ffmul(i ^ j, k) != (ffmul(i, k) ^ ffmul(j, k)))


     printf("ERROR!\n");



It is distributive and then my modification is also correct.



Thank for your responses, Tomek


Received on Tue Jan  3 03:41:27 2006