DPA on hardware implementations of Ascon and Keyak

Abstract

This work applies side channel analysis on hardware implementations of two CAESAR candidates, Keyak and Ascon. Both algorithms are cryptographic sponges with an iterated permutation. The algorithms share an s-box so attacks on the non-linear step of the permutation are similar. This work presents the first results of a DPA attack on Keyak using traces generated by an FPGA. A new attack is crafted for a larger sensitive variable to reduce the number of traces. It also presents and applies the first CPA attack on Ascon. Using a toy-sized threshold implementation of Ascon we try to give insight in the order of the steps of a permutation.