Seminario: "Canonical Liftings: Beyond Signature Compression" - Leonardo Errati

WG Meetings and Workshop (Ancona, Sept. 28–29)

Canonical Liftings: Beyond Signature Compression
Leonardo Errati (Politecnico di Torino)

Abstract: Canonical liftings provide a framework for compressing group-action-based Sigma protocols, generalising techniques such as the canonical forms used in LESS. Under suitable conditions, this compression preserves the hardness of the underlying group-action inversion problem. However, their role extends beyond compression. We adapt them for the construction of linkable ring signatures; our approach uses distinct but related secrets for signing and linkability, avoiding the secret-reuse mechanism that led to attacks on earlier constructions. Instantiating the framework with linear code equivalence yields CELeReS. We conclude with open questions: can canonical liftings support other primitives? can they be instantiated with other group actions?