SI-CP-ABE:一类基于同源的密文策略属性基加密方案OA

Ciphertext-policy attribute-based encryption(CP-ABE)serves as a fundamental cryptographic primitive for fine-grained data access control.However,existing schemes,primarily based on bilinear maps or lattice hard-ness assumptions,generally suffer from large system parameters,key sizes,and ciphertext sizes,which severely re-strict their deployment in resource-constrained scenarios.To address this challenge,a novel CP-ABE scheme based on supersingular elliptic curve isogeny(SI-CP-ABE)is proposed.This scheme integrates the action of isogeny ideal class group with linear secret sharing schemes,achieving efficient fine-grained access control in a post-quantum security setting.Regarding security,two new hardness assumptions—P+-CSSCDH and P+-CSSDDH—are proposed,based on which the scheme is rigorously proven to satisfy indistinguishability under chosen plaintext at-tack in the selective security model.To further enhance performance,an optimized scheme is designed based on SI-CP-ABE.Furthermore,based on the core algebraic structure of SI-CP-ABE,a post-quantum Naor-Reingold-type pseudo-random function with authentication capability is constructed,thereby enriching the building blocks for post-quantum cryptographic protocols.