Research On Searchable Symmetric Encryption Scheme Based On The Inner Product

With the development of cloud computing technology, more and more users choose to store data in the cloud server, such as mail server or file server. And the users usually store the encrypted data in the server in order to enhance the security of the file and protect the privacy of the user data. But for the sake of security, some functions would be affected, for example, if the user wants to retrieve the document containing some specific keywords, in the case that the data is encrypted, that is, in the case of protecting data privacy, how to search on the ciphertexts and return the documents containing the specific keywords becomes the problem to solve.Searchable encryption allows the data owner to upload the encrypted data to the cloud server, and the date owner transfers the key to the authorized user; Authorized users generate the trapdoor according to the received key and upload the trapdoor to the cloud server. If the cloud server searches successfully on the encrypted data, the cloud server would send the corresponding ciphertext to the authorized user. Finally,the user decrypts the received ciphertext. Throughout the whole process,we can not only ensure the privacy of the document, but also ensure the privacy of the keywords. Malicious users or the attacker can not get any information of keyword from the existion text.In this paper, we first introduce a searchable symmetric encryption scheme based on the inner product: it is more efficient to compute the inner product of two vectors. In our construction, the parties can be Data Owners, Clients or the Cloud Server. First, the data owner encrypts the data through the operation of the vector and uploads the encrypted data and encrypted keywords to the cloud server. And the data owner sends the generated keys to the authorized user. The authorized user generates the trapdoor according to the operation of the inner product of the vectors and uploads the trapdoor to the cloud server. The cloud server would search on the encrypted data and send the corresponding file to the user. The three parties communicate with each other through the inner product to achieve the goal that the client can search the data in the cloud without leaking any information on the data the owner stored in the cloud. We then perform a security analysis and performance evaluation, which show that our algorithm and construction are secure and efficient.