Tools for the cryptanalysis and design of symmetric cryptographic primitives

In recent years, symmetric cryptography has been through significant developments, particularly in the evaluation and improvement of the security of cryptographic primitives, which relies on a wide variety of techniques, among which differential cryptanalysis and its variants are central. Generic tools and models based on optimization techniques have been proposed in order to make the evaluation of the resistance of these primitives against certain attacks faster and more reliable.
First, we show how to improve cryptographic primitive designs by exploiting generic tools and models. Automating the process, one can explore numerous variants of the same algorithmic family in order to find a satisfactory trade-off between the performance of the primitive and its resistance to various classes of attacks.
In a second step, we describe new tools capable of automatically generating optimal attacks against existing primitives, thereby simplifying their analysis and evaluation.
Beyond these technical objectives, this thesis also contributes to a better understanding of the limits and possibilities offered by automatic tools in cryptanalysis. It thus fits into a research effort aimed at making cryptographic analysis more systematic, reproducible, and accessible to primitive designers.

Keywords: Symmetric Cryptography, MILP