English

Bent Functions in the Partial Spread Class Generated by Linear Recurring Sequences

Cryptography and Security 2021-12-17 v1 Combinatorics

Abstract

We present a construction of partial spread bent functions using subspaces generated by linear recurring sequences (LRS). We first show that the kernels of the linear mappings defined by two LRS have a trivial intersection if and only if their feedback polynomials are relatively prime. Then, we characterize the appropriate parameters for a family of pairwise coprime polynomials to generate a partial spread required for the support of a bent function, showing that such families exist if and only if the degrees of the underlying polynomials is either 11 or 22. We then count the resulting sets of polynomials and prove that for degree 11, our LRS construction coincides with the Desarguesian partial spread. Finally, we perform a computer search of all PS\mathcal{PS}^- and PS+\mathcal{PS}^+ bent functions of n=8n=8 variables generated by our construction and compute their 2-ranks. The results show that many of these functions defined by polynomials of degree b=2b=2 are not EA-equivalent to any Maiorana-McFarland or Desarguesian partial spread function.

Keywords

Cite

@article{arxiv.2112.08705,
  title  = {Bent Functions in the Partial Spread Class Generated by Linear Recurring Sequences},
  author = {Maximilien Gadouleau and Luca Mariot and Stjepan Picek},
  journal= {arXiv preprint arXiv:2112.08705},
  year   = {2021}
}

Comments

Completely revised version of "Bent functions from Cellular Automata" published in the Cryptology ePrint Archive. The construction here is described with linear recurring sequences instead of cellular automata, with new results. The original version in the ePrint archive is a standalone work discussing the connections between CA, Hadamard matrices, bent functions and orthogonal arrays

R2 v1 2026-06-24T08:19:55.440Z