NEON implementation of an attribute-based encryption scheme

Abstract

In 2011, Waters presented a ciphertext-policy attribute- based encryption protocol that uses bilinear pairings to provide control access mechanisms, where the set of user's attributes is specified by means of a linear secret sharing scheme. Some of the applications foreseen for this protocol lie in the context of mobile devices such a smartphones and tablets, which in a majority of instances are powered by an ARM processor supporting the NEON vector set of instructions. In this paper we present the design of a software cryptographic library that implements a 127-bit security level attribute-based encryption scheme over mobile devices equipped with a 1.4GHz Exynos 4 Cortex-A9 processor and a developing board that hosts a 1.7 GHz Exynos 5 Cortex-A15 processor. For the latter platform and taking advantage of the inherent parallelism of the NEON vector instructions, our library computes a single optimal pairing over a Barreto-Naehrig curve approximately 2 times faster than the best timings previously reported on ARM platforms at this level of security. Further, using a 6-attribute access formula our library is able to encrypt/decrypt a text/ciphertext in less than 7.5mS and 15.67mS, respectively. © 2013 Springer-Verlag.