| The data integrity audit mechanism can effectively verify the integrity of data stored in the cloud.However,most of the existing integrity audit schemes are based on the fact that the verifier is completely trustworthy,and do not consider the problem that the verifier tries to obtain the relevant content of the outsourced data block,nor does it take into account that the entities in the cloud environment are not credible,and there may be the problem of multiple attacks.Based on the above problems,this paper studies the integrity audit method of outsourced data in the cloud environment and proposes a verifiable data integrity check algorithm.The research has theoretical value and practical significance.The main research contents of this paper are as follows:(1)Aiming at the problem that the data owner needs to designate the verifier and the verifier is semi-trustworthy,this paper studies and proposes a remote data integrity audit scheme with a designated verifier.The scheme implements the operation of the designated verifier based on bilinear mapping;it also uses random numbers to blind the data integrity proof,which can resist the verifier’s curiosity attack;in addition,it also uses the Merkle hash tree structure to implement dynamic data operations.The security of the scheme is proved based on the discrete logarithm assumption and the computability Diffie-Hellman assumption.(2)Aiming at the problem that entities in the cloud environment may not be trusted,this paper studies and proposes a data integrity audit scheme that can resist multiple attacks.In the scheme,the data owner checks the verifier’s previous audit tasks through log records to resist attacks initiated by untrustworthy verifiers;the log files generated by the verifier are stored in the hash chain data structure,which can ensure the correctness and immutability of the audit results.Rely on unpredictable block hashes to generate challenging information that no entity can manipulate;entities can use nonrepudiation evidence to defend against defamation attacks.Security analysis shows that the scheme is safe under the random oracle model.According to the problem of multiple attacks in the cloud environment,combined with the block hash value,hash chain data structure,and random number blinding technology,this paper constructs a data integrity audit scheme to resist multiple attacks in the cloud environment.In addition,the research scheme in this paper is an identitybased cryptosystem,which avoids the complex key management problem in public key certificates.The experimental results show that the proposed scheme is feasible and effective in practical applications. |
