Research On Data Auditing Scheme In Cloud Storage Based On Certificateless Signature

With the high popularity of Internet technology,information and data are growing explosively.To reduce the burden of local data storage and management,individual users and enterprises are willing to store their data on the cloud server.However,data outsourcing also makes users lose direct control of data,which leads to the threat of data deletion and malicious tampering.Auditing technology can provide a strong guarantee for the integrity verification of data in cloud storage.However,most existing data auditing schemes in cloud storage are based on the traditional public key cryptosystem and identity cryptosystem,which have inherent certificate management and key escrow problems,and cannot satisfy the functional requirements of privacy protection,user revocation,data dynamic operation and user identity tracking.To solve the above problems,we study data auditing scheme in cloud storage based on certificateless signature.It includes the following contents:(1)For the certificateless signature scheme proposed by Wu,we use two kinds of attack algorithm to find that the scheme has neither strong unforgeability nor achieve the security under the key generation center attack.To solve these security risks,we proposed an improved certificateless signature scheme which is based on Wu scheme.The analysis result shows that the new scheme not only realizes the strong unforgeability of adaptive selection message attack under the standard model,but also has high computational performance.(2)For the third-party auditor steals group users' identity information in auditing process and other issues,we proposed a certificateless data auditing scheme in cloud storage for group users.The scheme establishes the reliable privacy protection mechanism to satisfy the anonymity of user identity;uses Lagrange interpolation formula to design the tracking mechanism for multiple administrators,which discloses the malicious user identity and avoids the abuse of tracking authority of single administrator;introduces the authentication process between the third-party auditor and the cloud service provider to reduce the network congestion and the waste of cloud resources.(3)For the third-party auditor steals shared data information in auditing process and other issues,we proposed a stateless data auditing scheme in cloud storage based on certificateless.The scheme uses the random mask technology to protect the security of shared data;establishes the efficient stateless auditing mechanism to reduce the computation overhead of data updating and auditing;supports the identity tracking mechanism without administrator to ensure the fairness of the tracking process;designs the secure data sharing mechanism to prevent malicious users from illegally stealing shared data resources;introduces the monitoring mechanism between the cloud service provider and users to ensure the non-repudiation of shared data;adopts the data storage mode of binary tree to support the dynamic operation of data,and realizes the traceability and recoverability of shared data;designs the safe and efficient group user revocation mechanism to avoid collusion attack between the revoked user and the cloud service provider.