logo EDITE Sujets de doctorat

Cryptanalysis of Symmetric Primitives in the Post-Quantum World

Résumé rédigé par
Directeur de thèse:
Doctorant: Xavier BONNETAIN
Unité de recherche INRIA 0 Institut National de Recherches en Informatique et en Automatique


Cryptography need to be ready for the post-quantum world. That is a fact, as shown by the effervescence about post-quantum asymmetric cryptography. Due to environmental constraints, it is very likely that common users will never take advantage of quantum capabilities, but a powerful adversary will. It is therefore vital that we dispose of primitives that are efficient on classical computers and secure against quantum adversaries. This means that we have definitely a lot of work to do with respect to symmetric cryptography. As symmetric cryptography completely lies in the variety and ever-changing landscape of symmetric cryptanalysis, we are convinced that it is not possible to determine for instance whether doubling the key length might make a concrete cipher secure or not in a post-quantum world, without first understanding how a quantum adversary could attack the primitive. Correctly evaluating the security of symmetric primitives in the post-quantum world cannot be done without a corresponding symmetric cryptanalysis toolbox, which neither exists nor has ever been studied. This PhD will contribute to fill this gap. The aim of this toolbox is two-fold: 1) analyze existing cryptosystems/primitives, and 2) design new ones which will give us confidence in the post-quantum world.