DOPIV: Post-Quantum Secure Identity-Based Data Outsourcing with Public Integrity Verification in Cloud Storage

Public verification enables cloud users to employ a third party auditor (TPA) to check the data integrity. However, recent breakthrough results on quantum computers indicate that applying quantum computers in clouds would be realized. A majority of existing public verification schemes are based on conventional hardness assumptions, which are vulnerable to adversaries equipped with quantum computers in the near future. Moreover, new security issues need to be solved when an original data owner is restricted or cannot access the remote cloud server flexibly. In this paper, we propose an efficient identity-based data outsourcing with public integrity verification scheme (DOPIV) in cloud storage. DOPIV is designed on lattice-based cryptography, which achieves post-quantum security. DOPIV enables an original data owner to delegate a proxy to generate the signatures of data and outsource them to the cloud server. Any TPA can perform data integrity verification efficiently on behalf of the original data owner, without retrieving the entire data set. Additionally, DOPIV possesses the advantages of being identity-based systems, avoiding complex certificate management procedures. We provide security proofs of DOPIV in the random oracle model, and conduct a comprehensive performance evaluation to show that DOPIV is more practical in post-quantum secure cloud storage systems.

1 Introduction

Along with the rapid development of network and communication techniques, massive data are produced. These massive data need to be real-time processed with much more strong computation capability and greater storage space. With cloud storage services, cloud users can remotely outsource their massive data to the cloud server and access them via the Internet flexibly [1]. These services relieve cloud users from complicated local storage management and maintenance. Although cloud users enjoy great benefits from these services, some security concerns may impede cloud users to employ cloud storage [2], [3]. One of the most important security concerns is the data integrity [4]. Once these data are outsourced to the cloud server which is maintained by a cloud service provider (CSP), cloud users will lose physical control over their data. Thus, they will always worry about whether the outsourced data are kept intact, especially for those of important ones.