Stateless hash-based signatures


SPHINCS+ is a stateless hash-based signature scheme, which was submitted to the NIST post-quantum crypto project. The design advances the SPHINCS signature scheme, which was presented at EUROCRYPT 2015. It incorporates multiple improvements, specifically aimed at reducing signature size. For a quick overview of the changes from SPHINCS to SPHINCS+ see the blog post by Andreas Hülsing. The submission proposes three different signature schemes:

  • SPHINCS+-SHA-256
  • SPHINCS+-Haraka

These signature schemes are obtained by instantiating the SPHINCS+ construction with SHAKE256, SHA-256, and Haraka, respectively.