Collusion-resistant dynamic privacy-preserving attribute-access control scheme based on blockchain

Ciphertext-policy attribute based encryption(CP-ABE) is widely used to protect data and privacy security in data sharing because of its fine-grained access control. However, due to the rapid development of the Internet and the explosive growth of all kinds of data and users, the traditional CP-ABE will make privacy and information face the risk of tampering and leakage. To solve the above problems, this paper proposes an attribute access control model based on blockchain technology for collusion-resistant dynamic privacy protection. The scheme effectively protects the integrity and confidentiality of encrypted data. In addition, resistant-regeneration key technology and chameleon hash function are used to generate collusion-resistant decryption key in this paper. Meanwhile, we verify the access right before decryption, and deploy fog node for outsourcing decryption. Finally, we provide the security of this scheme and make a comprehensive comparison with other schemes. The results show that this method is reliable and effective. (c) 2023 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).