Integrating Ciphertext-Policy Attribute-Based Encryption with Identity-Based Ring Signature to Enhance Security and Privacy in Wireless Body Area Networks

Abstract

The technology of wireless body area network (WBAN) has attracted intensive attention in recent years. For widespread deployment of WBANs, security and privacy issues must be addressed properly. Recently, Hu et al. proposed a fuzzy attribute-based signcryption scheme with the aim to provide security and privacy mechanisms in WBANs. In this paper, we first show Hu et al.’s scheme cannot achieve the claimed security properties. In particular, an adversary is capable of generating private keys for any set of attributes. Then we introduce a new cryptographic primitive named ciphertext-policy attribute-based ring signcryption (CP-ABRSC) by integrating the notion of ciphertext-policy attribute-based encryption with identity-based ring signature. We give formal syntax and security definitions for CP-ABRSC and present a provable secure CP-ABRSC scheme from bilinear pairings. Finally, we propose a novel access control framework for WBANs by exploiting CP-ABRSC scheme, which can not only provide semantic security, unforgeability and public authenticity, but also can provide participants privacy and fine-grained access control on encrypted health data.