Research On Searchable Encryption Technology In Cloud Storage

With the rapid development of information technology,cloud computing technology has gradually become a research hotspot in academia and industry.Cloud computing can provide users with massive data storage and efficient data processing capabilities.For resource constrained or computing constrained users,outsourcing data to a third-party cloud storage server can reduce the cost of software and hardware maintenance,and reduce the burden of user data management.Although cloud computing has many advantages,data privacy and confidentiality are common problems in current data outsourcing.To solve this problem,we can first encrypt the data and then outsource it to the cloud server for storage,but this limits the availability of data,including the computability and searchability of data.To solve the searchability problem of ciphertext data is one of the challenges in the context of data outsourcing.Searchable encryption technology can protect user's data privacy and enable users to retrieve encrypted data directly.In view of the different shortcomings and deficiencies in the data outsourcing scenario,this paper proposes the corresponding solutions from the functional improvement of the searchable encryption scheme.This paper summarizes the research points as follows:(1)in the searchable encryption scheme,how to ensure the correctness and integrity of the search results(2)In the searchable encryption scheme,how to control the user's access(3)In searchable encryption scheme,how to do fuzzy search on encrypted data? The main research achievements of this paper include:1.Solve the problem of server forgery,tampering with the search results and other illegal behavior under the malicious model.Most of the traditional searchable encryption schemes are put forward under the honest and curious model,which lacks the verification of the integrity and correctness of the retrieval results.Because the cloud server is not completely trusted,there may be incorrect execution of user retrieval requests,so it is necessary to verify the retrieval results returned by the cloud server.The first scheme proposed in this paper is put forward under this background.Aiming at the problem that the traditional searchable encryption scheme lacks the verification of the search results,a searchable encryption scheme based on bilinear mapping verifiable sorting is designed.The scheme realizes sub linear search based on inverted index,resists keyword frequency attack of malicious server by inserting confusing keywords in dictionary,and generates tags for keywords based on bilinear mapping,which can identify possible tampering and forgery of search results in cloud server.2.Implement multi keyword search based on attribute encryption and attribute revocation.In the cloud storage environment,the user's attributes are dynamic.For example,if the user's permission is reduced,the user will lose some attributes,but the secret key corresponding to the lost attributes is still in the user's hands,then the security of access and retrieval of ciphertext in the cloud storage environment will not be guaranteed.Aiming at the problem that attribute based searchable encryption does not support attribute revocation,this paper proposes a secure,efficient and attribute revocable connection keyword searchable encryption scheme based on cp-abe in cloud storage environment.The efficiency of LSSS access structure is higher than that of traditional tree access structure,and the scheme meets the requirement of plaintext security in general model.The scheme supports fine-grained access control and has high computational efficiency.3.A fuzzy multi keywords searchable encryption(FMKSE)query scheme is proposed.Compared with other fuzzy keyword query schemes,FMKSE uses Euclidean distance to measure the similarity between keywords,and does not need to predefine similar keyword dictionary,which effectively saves storage space.When constructing the security index,the inverted file vector in the bucket is encrypted with the Paillier encryption algorithm,which ensures the security and privacy of the index.When users query keywords,they only need to submit the bucket number processed by pseudo-random permutation function,which ensures the privacy of query keywords.And during the query,only one round of Paillier encryption and decryption operation is needed,and it does not need to scan each index item in order,so it has high query efficiency.