A Trustworthy Ciphertext-Policy Attribute-Based Encryption Access Control Method Based on FAME and Blockchain

Abstract

Ciphertext-policy attribute-based encryption (CP-ABE) has been extensively applied in various types of conditional access control systems since its introduction because of its ability to provide fine-grained and flexible access control to confidential data, thus offering a safe and effective data sharing environment. However, while developing rapidly, the existing CP-ABE access schemes also face some problems, such as trustworthiness issues involving third-party intermediary entities, secret key management problems brought by single attribute authorization centers, and privacy leakage of attributes. How to achieve safe and effective decentralized access control has been a problem to be explored and solved. In this paper, a trustworthy, secure, and efficient ABE(TSE ABE) based on blockchain and fast attribute-based message encryption (FAME) is proposed by us. First, we combine blockchain and FAME and optimize them to make CP-ABE perform better. Second, we implement a trusted authorization model with multiple entities based on the BLS signature and smart contracts to address key privacy issues. Finally, we protect the privacy of attributes in the authorization matching process by RSA encryption algorithm. Through the experimental results, it can be found that the scheme not only has good security and execution performance but also achieves effective protection of user privacy.