Research On Application Of Cryptography Technology Of Personal Archives Management Based On Consortium Blockchain

Personal archives are important archives to record personal health status,academic performance,quality level,integrity records,etc.Traditional archival data management has some problems such as highly centralized data management,insecure data sharing and cumbersome verification of offline certificates in application scenarios such as job hunting,entrance qualification examination and personal credit evaluation.In this paper,a personal archival management scheme based on consortium blockchain,using no certificate searchable encryption and attribute-based encryption technologies is proposed.The searchable ciphertext keyword technology is used to search the document ciphertext to protect the privacy of key words.The certificateless encryption technology is used to solve the key escrow problem.The attribute cryptography technology is used to realize the fine-grained data access control and solve a pair of additional decryption problems.The consortium blockchain has the characteristics of decentralization,openness and transparency,and cannot be tampered with.It can sign important information and record transactions to the consortium blockchain,realize open storage and traceability of archival data after encryption,and enhance the credibility of various authorities.The access structure of traditional attribute-based encryption technology cannot describe the access strategy based on complex operation relations,which severely limits its application expansion.This paper proposes a method to enrich the access control strategy of data authorization.The main work is as follows:1.Aiming at the problems of highly centralized management of file data,insecure sharing and tedious verification of offline certificate,this paper proposes a personal archives management scheme based on consortium blockchain and certificateless searchable encryption technology.In the scheme,a consortium blockchain is constructed to record and query personal archives safely and conveniently,and the credibility of authority is enhanced through the blockchain.The certificateless searchable encryption technology is used to realize ciphertext keyword retrieval,solve the problem of key escrow in certificate management,and realize file security retrieval.Attribute-based encryption technology is introduced in this scheme to provide fine-grained data access policies so that data owners can set one-to-many flexible access policies.The scheme has the properties of privacy protection,anti-key escrow,fine-grained access,decentralization and anti-tampering,making the archival data more real,credible and easy to operate.The experimental results show that the scheme is safe and has high computational performance.2.Aiming at the problem that attribute based access structure cannot describe the complex dynamic access strategy based on attribute in archives access,this paper proposes an attribute-based encryption scheme based on LSSS access structure with expressive dynamic attributes.By constructing various operation expressions of attributes,such as arithmetic operation,relational operation and string operation,complex attribute access structure is established,and more general and flexible access strategy is realized.In this scheme,a dynamic attribute partitioning method is proposed to avoid one attribute appearing in two different dynamic attribute expressions and maintain its fine-grained characteristics.Under the q-PBDHE assumption of standard model,the scheme is proved to be safe.The safety and experimental analysis of the scheme are carried out,and the results show that the scheme is safe and has high computational performance.