What can Information Guess? Guessing Advantage vs. Rényi Entropy for Small Leakages
Résumé
We leverage the Gibbs inequality and its natural generalization to Rényi entropies to derive closed-form paramet- ric expressions of the optimal lower bounds of ρth-order guessing entropy (guessing moment) of a secret taking values on a finite set, in terms of the Rényi-Arimoto α-entropy. This is carried out in an non-asymptotic regime when side information may be available. The resulting bounds yield a theoretical solution to a fundamental problem in side-channel analysis: Ensure that an adversary will not gain much guessing advantage when the leakage information is sufficiently weakened by proper countermeasures in a given cryptographic implementation. Practical evaluation for classical leakage models show that the proposed bounds greatly improve previous ones for analyzing th
| Origine | Fichiers produits par l'(les) auteur(s) |
|---|---|
| licence |