On a Generalization of Substitution-Permutation Networks: The HADES Design Strategy

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Keyed and unkeyed cryptographic permutations often iterate simple round functions. Substitution-permutation networks (SPNs) are an approach that is popular since the mid 1990s. One of the new directions in the design of these round functions is to reduce the substitution (S-Box) layer from a full one to a partial one, uniformly distributed over all the rounds. LowMC and Zorro are examples of this approach.

A relevant freedom in the design space is to allow for a highly non-uniform distribution of S-Boxes. However, choosing rounds that are so different from each other is very rarely done, as it makes security analysis and implementation much harder.

We develop the design strategy Hades and an analysis framework for it, which despite this increased complexity allows for security arguments against many classes of attacks, similar to earlier simpler SPNs. The framework builds upon the wide trail design strategy, and it additionally allows for security arguments against algebraic attacks, which are much more of a concern when algebraically simple S-Boxes are used.

Subsequently, this is put into practice by concrete instances and benchmarks for a use case that generally benefits from a smaller number of S-Boxes and showcases the diversity of design options we support: A candidate cipher natively working with objects in GF(p), for securing data transfers with distributed databases using secure multiparty computation (MPC). Compared to the currently fastest design MiMC, we observe significant improvements in online bandwidth requirements and throughput with a simultaneous reduction of preprocessing effort, while having a comparable online latency.
Original languageEnglish
Title of host publicationAdvances in Cryptology – EUROCRYPT 2020
Subtitle of host publicationLecture Notes in Computer Science
PublisherSpringer, Cham
Pages674-704
Volume12106
ISBN (Electronic)978-3-030-45724-2
ISBN (Print)978-3-030-45723-5
DOIs
Publication statusPublished - 2020
EventEurocrypt 2020 -
Duration: 11 May 202015 May 2020
https://eurocrypt.iacr.org/2020/

Conference

ConferenceEurocrypt 2020
Period11/05/2015/05/20
Internet address

Keywords

  • Hades strategy
  • Cryptographic permutations
  • Secure Multiparty Computation (MPC)

Fingerprint Dive into the research topics of 'On a Generalization of Substitution-Permutation Networks: The HADES Design Strategy'. Together they form a unique fingerprint.

  • Cite this

    Grassi, L., Lüftenegger, R., Rechberger, C., Rotaru, D., & Schofnegger, M. (2020). On a Generalization of Substitution-Permutation Networks: The HADES Design Strategy. In Advances in Cryptology – EUROCRYPT 2020: Lecture Notes in Computer Science (Vol. 12106, pp. 674-704). Springer, Cham. https://doi.org/10.1007/978-3-030-45724-2_23