A Generic Construction of Predicate Proxy Key Re-encapsulation Mechanism

Abstract

Proxy re-encryption (PRE), first formalized by Blaze et al . in 1998, allows a proxy entity to delegate the decryption right of a ciphertext from one party to another without obtaining the information of the plaintext. In order to achieve more flexible access control, the predicate proxy re-encryption (PPRE) is studied further. However, existing PPRE is restricted with the inner product predicate function. The problem of how to realize the PPRE of arbitrary predicate functions is still to be solved. In this paper, we propose two secure generic predicate proxy key re-encapsulation mechanisms (PPKREM). By applying the key encapsulation mechanism/ data encapsulation mechanism paradigm, our PPKREM can be converted to a PPRE.  Consequently, the results open new avenues for building more flexible and fine-grained PPRE.