ACM SIGSAC Conference on Computer and Communications Security (CCS)

Practical, Round-Optimal Lattice-Based Blind Signatures

Shweta Agrawal, Elena Kirshanova, Damien Stehlé, Anshu Yadav

Published Nov 7, 2022• 66 citations

Abstract

Blind signatures are a fundamental cryptographic primitive with numerous practical applications. While there exist many practical blind signatures from number-theoretic assumptions, the situation is far less satisfactory from post-quantum assumptions. In this work, we provide the first overall practical, lattice-based blind signature, supporting an unbounded number of signature queries and additionally enjoying optimal round complexity. We provide a detailed estimate of parameters achieved -- we obtain a signature of size slightly above 45KB, for a core-SVP hardness of 109 bits. The run-times of the signer, user and verifier are also very small.

DOI: 10.1145/3548606.3560650

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