The SPHINCS+ Signature Framework

Daniel J.  Bernstein; Andreas Hülsing; Stefan Kölbl; Ruben Niederhagen; Joost Rijneveld; Peter Schwabe

Paper 2019/1086

The SPHINCS+ Signature Framework

Daniel J. Bernstein, Andreas Hülsing, Stefan Kölbl, Ruben Niederhagen, Joost Rijneveld, and Peter Schwabe

Abstract

We introduce SPHINCS+, a stateless hash-based signature framework. SPHINCS+ has significant advantages over the state of the art in terms of speed, signature size, and security, and is among the nine remaining signature schemes in the second round of the NIST PQC standardization project. One of our main contributions in this context is a new few-time signature scheme that we call FORS. Our second main contribution is the introduction of tweakable hash functions and a demonstration how they allow for a unified security analysis of hash-based signature schemes. We give a security reduction for SPHINCS+ using this abstraction and derive secure parameters in accordance with the resulting bound. Finally, we present speed results for our optimized implementation of SPHINCS+ and compare to SPHINCS-256, Gravity-SPHINCS, and Picnic.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Published elsewhere. Major revision. CCS 2019
DOI: 10.1145/3319535.3363229
Keywords: Digital signature post-quantum cryptography SPHINCS hash-based signatures stateless tweakable hash functions NIST PQC exact security
Contact author(s): contact @ sphincs org
History: 2019-09-25: received
Short URL: https://ia.cr/2019/1086
License: CC BY

BibTeX

@misc{cryptoeprint:2019/1086,
      author = {Daniel J.  Bernstein and Andreas Hülsing and Stefan Kölbl and Ruben Niederhagen and Joost Rijneveld and Peter Schwabe},
      title = {The SPHINCS+ Signature Framework},
      howpublished = {Cryptology ePrint Archive, Paper 2019/1086},
      year = {2019},
      doi = {10.1145/3319535.3363229},
      note = {\url{https://eprint.iacr.org/2019/1086}},
      url = {https://eprint.iacr.org/2019/1086}
}