A metaverse-oriented CP-ABE scheme with cryptographic reverse firewall

Abstract

Metaverse is an immersive, hyperspace virtual reality space. Due to its characteristics of hyperspace and immersive realism, metaverse has a bright future, but ubiquitous user analysis and calculation make it difficult to achieve one-to-multiple data sharing. As an innovative encryption algorithm, ciphertext-policy attribute-based encryption (CP-ABE) can realize one-to-multiple secure file sharing through fine-grained access control. Many evidences show that attackers may add backdoors to internal devices to make encryption algorithms insecure, CP-ABE also faces the above threats. In order to deal with such attacks, researchers put forward the notion of cryptographic reverse firewall (CRF), which has the ability of resistance to insider attack. However, the existing ABE scheme supporting CRF have the problems of low efficiency and no support for malicious user tracking. To improve safety and efficiency, we constructed an efficient CP-ABE scheme supporting CRF protection which has function of outsourcing decryption, offline encryption and black-box tracking.