Adaptive oblivious transfer with hidden access policy realizing disjunction

We propose an efficient adaptive oblivious transfer protocol with hidden access policies. This scheme allows a receiver to anonymously recover a message from a database which is protected by hidden attribute based access policy if the receiver´s attribute set satisfies the associated access policy implicitly. The proposed scheme is secure in the presence of malicious adversary under the q-Strong Diffie-Hellman (SDH), q-Power Decisional Diffie-Hellman (PDDH) and Decision Bilinear Diffie-Hellman (DBDH) assumption in full-simulation security model. The scheme covers disjunction of attributes. The proposed protocol outperforms the existing similar schemes in terms of both communication and computation.