Password typo correction using discrete logarithms

Nikola K Blanchard (1)

1 LORIA - ALGO - Department of Algorithms, Computation, Image and Geometry

As passwords remain the main online authentication method, focus has shifted from naive entropy to how usability improvements can increase security. Chatterjee et al. recently introduced the first two typo-tolerant password checkers, which improve usability at no security cost but are technically complex. We look at the more general problem of computing an edit distance between two strings without having direct access to those strings-by storing the equivalent of a hash. We propose a simpler algorithm for this problem that is asymptotically quasi-optimal in both bits stored and exchanged, at the cost of more computation on the server.

Mots clés: Usable security; Passwords; Discrete logarithms

Domaines: Cryptographie et sécurité [cs.CR]

Nikola K Blanchard. Password typo correction using discrete logarithms. IC-CSCE 2019 - 8th International Conference on Computer Science and Communication Engineering, Oct 2019, Pristine, Kosovo. ⟨hal-02550719⟩