Structured query language (SQL) rewrite based database external encryption/decryption system and usage method thereof

Abstract

The invention provides an SQL rewrite based database external encryption / decryption system and a usage method thereof. The system comprises an SQL rewrite main module, a statement parsing module, a grammatical rule management module, an encryption / decryption table management module, a rewrite execution module and a data encryption / decryption module. The method comprises the steps of executing a rewritten data sheet creation process, a rewritten data insertion process and a data query process. According to the system and the method, an SQL rewrite technology is used, and data are encrypted and decrypted outside a database system, so that encryption / decryption costs of the database system are avoided.

Description

technical field [0001] The invention relates to the field of database encryption, in particular to a database encryption and decryption method based on SQL rewriting technology. Background technique [0002] The leakage of private data is a serious threat to the current database system. Malicious database administrators can access database management system servers to obtain private data (including health records, financial stocks, personal information, etc.) and sell them to third parties. One way to address this threat is to encrypt sensitive data in the database, but most database systems are not suitable for this approach. This approach will have many insurmountable negative effects. First of all, the database system has to deal with a large number of user and program query requests and generate data back. There is a serious conflict between a large amount of confidential data and effective query execution performance. The current calculation method for ciphertext dat...

AI Technical Summary

Problems solved by technology

The current calculation method for ciphertext data is either inefficient or cannot provide sufficient confidentiality. For example, the ciphertext data obtained by using a strong encryption algorithm will prevent the database server from executing SQL query commands.

Secondly, the current database encryption system must first decrypt the encrypted data table during the query, and then match the plaintext data with the query SQL, resulting in the exposure of the plaintext data to the database system, and database managers have the opportunity to steal plaintext sensitive data

In addition, the database side decrypts the query results, and the query results are returned to the application layer in plain text, which is easy to be stolen during transmission, resulting in the leakage of sensitive data

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