Certificateless public auditing scheme with designated verifier and privacy-preserving property in cloud storage

Abstract

In recent years, cloud storage has become an attractive service for data owners to store their personal data. Since they lose physical control of their data, it is necessary to regularly audit its integrity. The public auditing technique is very popular because it is suitable to outsource the auditing task to any third-party auditor, who has professional knowledge on auditing. However in many practical scenarios, the data owner may expect some designated verifier (instead of any) to audit its data. Thus, the public auditing scheme with designated verifier was proposed. In order to further reduce the cost of managing certificates, and to avoid the dependence on public key infrastructure , identity-based auditing scheme with designated verifier was recently proposed. Nevertheless, the proposed identity-based auditing scheme still suffers from the key escrow attack the risk of privacy leakage . In this paper, for the first time, we propose a certificateless public auditing protocol with designated verifier privacy-preserving property. More concretely, it can not only protect the privacy of the stored data against the designated verifier, but also resolve key escrow problem existed in identity-based technique. Its security is based on the Computational Diffie–Hellman and Weil Diffie–Hellman assumptions. Finally, the performance analysis experimental results of the proposed protocol show that our auditing scheme is efficient feasible to applications in real life.