Research On Cloud Data Integrity Verification Based On Proxy Re-signature

In recent years,due to the rapid increase in the amount of data,people's demand for hardware continues to increase,leading to increased local storage pressure.To reduce storage costs,users who choose to upload their own locally stored data to the cloud are gradually increasing.The cloud server has a large storage space and a low cost.After the user uploads data to the cloud server,the local data is deleted,thereby reducing the use of local storage space.However,the development of cloud storage technology has brought convenience to users while also facing users with many security challenges.After the user uploads data to the cloud server,he loses control of the data and cannot ensure the integrity of the data.Therefore,data integrity verification issues are particularly important.In practical applications,after the user uploads data to the cloud server,the data stored in the cloud server may be updated.The user may also be not only a single individual,but may be a company.After the manager of the company uploads the data to the cloud server,the data administrator is employed to manage the data in the cloud.However,the data administrator has a separation,etc.The management cycle is not a lifelong system.Therefore,it is necessary to implement the user's revocation function and solve the problem of user authority change.In order to solve the above problems,this paper adopts proxy re-signature technology,multi-branch path tree and hash tree,and proposes two cloud data integrity verification schemes respectively.(1)A new cloud data integrity verification scheme was constructed.Using proxy re-signature technology,using the signature conversion function in re-signature to solve changes to the data management rights on the cloud server,supporting user revocable functions.Using multi-branch path tree to support the dynamic update of data stored on the cloud server.The introduction of random mask technology ensures the privacy of data stored on the cloud server.At the same time,under the random prediction model(RO model),it is proved that the new scheme satisfies the existence of unforgeability,anti-replay attack and anti-deletion attack.(2)Based on one-way proxy re-signature techniques,hash trees and pseudo-random functions,a new cloud data public auditing scheme was proposed.Based on the one-way proxy re-signature technology,the re-signing key is generated by the unrevoked user's private key and the revoked user's public key,effectively solving the problem of re-signing key leakage,and ensuring the secure transfer of data management rights on the cloud server.Effectively solve the problem of user revocable.Using a hash tree can support users to dynamically update the data stored on the cloud server.