Recipient Anonymous Ciphertext-Policy Attribute Based Encryption

摘要

Attribute Based Encryption (ABE) is a promising and increasingly versatile paradigm. Given the many potential uses of ABE schemes, constructing efficient schemes that provide recipient anonymity via policy hiding while ensuring constant-size secret key and ciphertext with strong security notion is a challenging task. In this paper, we propose a fully secure recipient anonymous Ciphertext-Policy ABE (CP-ABE) scheme using an AND-gate access policy. The secret key size, ciphertext size and computation costs are all constant in our scheme. To the best of our knowledge, this is the first fully secure CP-ABE scheme with hidden access policy as well as constant ciphertext length which preserves recipient anonymity. The security analysis is in non-selective model under four static assumptions over composite order bilinear groups.