Aymeric Hiltenbrand, Julien Eynard, Romain Poussier
ePrint Report
Side-channel attacks following a classical differential power
analysis (DPA) style are well understood, along with the effect the mask-
ing countermeasure has on them. However, simple attacks (SPA) where
the target variable does not vary thanks to a known value, such as the
plaintext, are less studied. In this paper, we investigate how the masking
countermeasure affects the success rate of simple attacks. To this end, we
provide theoretical, simulated, and practical experiments. Interestingly,
we will see that masking can allow us to asymptotically recover more
information on the secret than in the case of an unprotected implemen-
tation, depending on the masking type. We will see that this is true for
masking encodings that add non-linearity with respect to the leakages,
such as arithmetic masking, while it is not for Boolean masking. We be-
lieve this context provides interesting results, as the average information
of arithmetic encoding is proven less informative than the Boolean one.
