基于无双线性对的可信云数据完整性验证方案

针对云审计中第三方审计机构（TPA）可能存在的恶意欺骗行为，提出一种无双线性对的、能够正确检查TPA行为的可信云审计方案。首先，利用伪随机比特生成器生成随机挑战信息，以保证TPA生成挑战信息可靠；其次，在证据生成过程中增加哈希值，从而有效保护用户数据隐私；然后，在证据验证过程中，增加用户和TPA结果的交互过程，根据这个结果检查数据完整性，并判断TPA是否如实完成审计请求；最后，扩展该方案以实现多项数据的批量审计。安全分析表明，所提方案能够抵抗替换攻击和伪造攻击，且能保护数据隐私。相比基于Merkle哈希树的无双线性对（MHT-WiBPA）审计方案，所提方案的验证证据时间接近，而标签生成时间降低约49.96%。效能分析表明，所提方案在保证审计结果可信的前提下，实现了更低的计算开销和通信开销。

Trusted integrity verification scheme of cloud data without bilinear pairings

Focusing on the malicious cheating behaviors of Third Party Auditor （TPA） in cloud audit， a trusted cloud auditing scheme without bilinear pairings was proposed to support the correct judgment of the behaviors of TPA. Firstly， the pseudo-random bit generator was used to generate random challenge information， which ensured the reliability of the challenge information generated by TPA. Secondly， the hash value was added in the process of evidence generation to protect the privacy of user data effectively. Thirdly， in the process of evidence verification， the interactive process between users and TPA results was added. The data integrity was checked and whether TPA had completed the audit request truthfully or not was judged according to the above results. Finally， the scheme was extended to realize batch audit of multiple data. Security analysis shows that the proposed scheme can resist substitution attack and forgery attack， and can protect data privacy. Compared with Merkle-Hash-Tree based Without Bilinear PAiring （MHT-WiBPA） audit scheme， the proposed scheme has close time for verifying evidence， and the time for generating labels reduced by about 49.96%. Efficiency analysis shows that the proposed scheme can achieve lower computational cost and communication cost on the premise of ensuring the credibility of audit results.