CsiIBS: A post-quantum identity-based signature scheme based on isogenies

Abstract Digital signatures are important cryptographic primitive for authentication. To resist quantum attacks, many post-quantum signature schemes have been proposed. Among them, isogeny-based signature schemes, such as SeaSign, rapid development in recent years along with the proposed CSIDH construction. In this paper, inspired by the Fiat-Shamir transform, we construct the first identity-based signature scheme based on isogenies from the isogeny-based identification scheme. Then, we analyze its security in the random oracle model under the hardness of the isogeny problem, and demonstrate that it achieves the required security properties. Finally, we evaluate the performance and give the corresponding computational and storage costs.