T-ABE: A practical ABE scheme to provide trustworthy key hosting on untrustworthy cloud

Attribute-based encryption (ABE) is a highly promising mechanism for secure fine-grained access control over encrypted data, particularly in cloud storage applications. However, the integration of built-in key escrow and susceptibility to key exfiltration poses a prevalent challenge during the implementation of ABE. In this paper, we present a novel ABE scheme called T-ABE to address the above challenges. Specifically, T-ABE utilizes a Trusted Execution Environment (i.e. Intel SGX) to provide a precise security guarantee for the entire process, from establishing trust between users and ABE services to key generation and management, ensuring that the entire scheme can provide users with secure and reliable ABE key hosting services even when deployed in untrustworthy cloud service providers. Through comprehensive security analysis and experimental demonstration, we have demonstrated the advantages of T-ABE in practical applications. We are confident that this new scheme has the potential to effectively tackle the outsourced key escrow challenges encountered by ABE.