In this paper we look at the number and the type of relations that do exist for several well known components. We wish to correct or/and complete several inexact results on this topic that were presented at FSE 2004.
We also wish to bring a theoretical contribution. One of the main problems in the area of algebraic attacks is to prove that some systems of equations (derived from some more fundamental equations), are still linearly independent. We give a complete proof that the number of linearly independent equations for the Rijndael S-box (derived from the basic equation XY=1) is indeed as reported by Courtois and Pieprzyk. It seems that nobody has so far proven this fundamental statement.
Category / Keywords: secret-key cryptography / Boolean functions, algebraic attacks, block ciphers, stream ciphers Date: received 28 Jun 2005, last revised 5 May 2006 Contact author: courtois at minrank org Available formats: Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation Note: This paper is (and should be) dedicated to the memory of Hans Dobbertin [1952-2006], that is recognised for his substantial contributions to the theory of Boolean functions, and did also pioneering work (that remains classified) in the area of algebraic cryptanalysis. Version: 20060505:204711 (All versions of this report) Discussion forum: Show discussion | Start new discussion