Verifiable semantically secure multi-keyword search method in cloud storage

Abstract

The invention relates to a multi-keyword search method with verifiable semantic security in cloud storage, including system initialization, establishment of a shared key between TA and data owner, data owner's encryption of data files and their indexes, and TA generating query traps. Gate, cloud server security query, and query user verification query results six steps, the present invention realizes semantically secure multi-keyword connection query for encrypted index through inner product predicate encryption and dual system encryption, and introduces trusted TA , realizes fine-grained authorization, overcomes the shortcomings of the traditional "0" or "1" authorization model, TA verifies the query qualifications of query users and sends query trapdoors for verified users, which solves the needs of data owners For the problem of being online all the time, the present invention can realize fine-grained authorization, can resist dictionary attacks, can verify the correctness of query results, and is a semantically safe multi-keyword search method.

Description

technical field [0001] The invention relates to the technical field of encrypted search, in particular to a multi-keyword search method with verifiable semantic security in cloud storage. Background technique [0002] Cloud computing, as a new computing model after distributed computing and grid computing, can provide powerful data storage, management and computing capabilities. In recent years, with the rapid development of cloud computing, many companies or organizations have begun to outsource data to cloud servers, which not only enables users to access remote data anytime and anywhere, but also reduces users' local computing and maintenance costs. However, cloud servers are maintained and managed by third-party Internet commercial companies (such as Amazon, Google, etc.), and usually do not belong to the same trust domain as users. Therefore, while cloud computing brings convenient services, it may also cause severe security risks. In order to protect data security an...

AI Technical Summary

Problems solved by technology

However, in this scheme, the user's authorization still adopts the "0" or "1" authorization model. Once the user is authorized, the user management agency will send the key that can be used to generate the query trapdoor to the querying user, that is, the authorized key. The "1" model, such an authorization method allows users to request any multi-keyword connection query, which cannot meet the requirements in many applications, and there is no query result verification function in this solution

[0007] The Chinese patent with the application number CN201711332605.0 "Certificate-free verifiable multi-keyword ciphertext query system and method" specifically relates to a non-certificate verifiable multi-keyword ciphertext query system and method, which introduces a key In this scheme, the key generation center is different from the traditional ciphertext query based on the public key encryption algorithm. In this paper, the key generation center is also assumed to be untrustworthy. The information generates a partial private key, and the data owner and data user generate a complete private key based on the partial private key and secret value, so that the key generation center cannot obtain the private key of the data owner and data user, thus increasing the protection of the private key. safety

However, in this technical solution, the user’s authorization description is not clear, and before the data owner outsources the data, the data owner uses the public key encryption algorithm to encrypt the plaintext document set. Since the public key encryption algorithm has the characteristics of slow encryption speed, all Encrypting relatively large plaintext files with public key algorithms is impractical

Moreover, this technical solution only provides a technical framework, and does not provide a specific algorithm description

[0008] Moreover, the four existing technologies listed above are not semantically secure, which is not enough security for applications with semantic security requirements

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