Public Key Encryption With Keyword Search Against Inside Keyword Guessing Attack

The rapid development of technologies like the Internet and the Internet of Things has led to explosive growth in the data and information of enterprises and individuals,which makes the local processing and analysis of data a huge burden for users.Therefore,users have to choose to outsource their private data to a third-party cloud server for storage and processing.However,cloud is not generally considered a fully trusted service provider.Users need to encrypt their data before using outsourcing service to ensure the privacy and security of their data.This leads to a new problem: how to execute keyword search operations safely and speedily in the ciphertext domain? This article focuses on how to implement secure and efficient searchable encryption under public key environment.The followings are the main study contents:1.For the public key encryption mechanism,the decryption of ciphertext remains inefficiency and the keywords in searchable scheme are vulnerable to be attacked.We propose an efficient decipherable and keyword-safe,complete public key encryption scheme with keyword search,and describe the process of construction in detail.This scheme introduces the public and private key pairs of the server into the process of encrypting and decrypting the plaintext,and makes the server bear the vast majority of the decryption overhead,thereby the decryption burden of user is greatly reduced;at the same time,the user's private key is added to the construction of the encrypted index.This makes it possible to generate a legitimate encrypted index only if the user who possesses this private key.This method can effectively prevent inside adversaries from implementing keyword guessing attack through encrypted indexes and trapdoors,thereby the security of the scheme is improved.2.For the problem of inefficiency of search in searchable encryption,we analyze the hidden structure based on the inverted index,improve the construction of the encrypted index,and at the same time combine with the public key partial decryption technology,propose an efficient decipherable,efficient searchable and keywordsafe public key scheme.This scheme reduces the execute count of bilinear pairing operations performed by the server during the search phase while supporting the server pre-decryption and against inside keyword guessing attack.Therefore the the search efficiency is improved and the scheme becomes more practical.3.For the above-mentioned efficient searchable scheme,we propose a new security model named chosen keyword attack for the specified structure(CKA-SS)model,and analyze the security of the scheme under this model;at the same time,a hybrid application scenario is presented for the high efficiency features of the scheme in decrypting and searching,and a detailed description of each stage is given;finally,through the analysis of the efficiency of the scheme,the practical application of the scheme is proved.