Skip to Main content Skip to Navigation
Journal articles

Spook: Sponge-Based Leakage-Resistant Authenticated Encryption with a Masked Tweakable Block Cipher

Abstract : This paper defines Spook: a sponge-based authenticated encryption with associated data algorithm. It is primarily designed to provide security against side-channel attacks at a low energy cost. For this purpose, Spook is mixing a leakageresistant mode of operation with bitslice ciphers enabling efficient and low latency implementations. The leakage-resistant mode of operation leverages a re-keying function to prevent differential side-channel analysis, a duplex sponge construction to efficiently process the data, and a tag verification based on a Tweakable Block Cipher (TBC) providing strong data integrity guarantees in the presence of leakages. The underlying bitslice ciphers are optimized for the masking countermeasures against side-channel attacks. Spook is an efficient single-pass algorithm. It ensures state-ofthe-art black box security with several prominent features: (i) nonce misuse-resilience, (ii) beyond-birthday security with respect to the TBC block size, and (iii) multiuser security at minimum cost with a public tweak. Besides the specifications and design rationale, we provide first software and hardware implementation results of (unprotected) Spook which confirm the limited overheads that the use of two primitives sharing internal components imply. We also show that the integrity of Spook with leakage, so far analyzed with unbounded leakages for the duplex sponge and a strongly protected TBC modeled as leak free, can be proven with a much weaker unpredictability assumption for the TBC. We finally discuss external cryptanalysis results and tweaks to improve both the security margins and efficiency of Spook.
Document type :
Journal articles
Complete list of metadata
Contributor : Gaëtan Leurent Connect in order to contact the contributor
Submitted on : Tuesday, February 9, 2021 - 5:23:07 PM
Last modification on : Friday, January 21, 2022 - 3:17:11 AM
Long-term archiving on: : Monday, May 10, 2021 - 7:06:31 PM


8623-Article Text-5221-2-10-20...
Files produced by the author(s)


Distributed under a Creative Commons Attribution 4.0 International License




Davide Bellizia, Francesco Berti, Olivier Bronchain, Gaëtan Cassiers, Sébastien Duval, et al.. Spook: Sponge-Based Leakage-Resistant Authenticated Encryption with a Masked Tweakable Block Cipher. IACR Transactions on Symmetric Cryptology, Ruhr Universität Bochum, 2020, Special Issue on Designs for the NIST Lightweight Standardisation Process, 2020 (S1), pp.295--349. ⟨10.13154/tosc.v2020.iS1.295-349⟩. ⟨hal-03136493⟩



Les métriques sont temporairement indisponibles