Isogeny-based Proxy Signature

Proxy signatures are protocols used when a signer wishes to delegate their ability to sign. The original signer will delegate its signing right to a proxy signer, who will then be able to output a proxy signature on the original signer’s behalf. In this paper, we propose an isogeny-based proxy signature by using the Commutative Supersingular Isogeny-based Fiat-Shamir signature (CSI-FiSh) as a basis. We prove the resulting proxy signature scheme is EUF-CMA-CWA in the Quantum random oracle model. We then compare our scheme to the base signature.