Leakage resilient Attribute based Encryption with CCA2 Security
Leakage resilient Attribute Based Encryption (ABE) is one of efficient methods to solve the side channel attacks. However, most of existing works only achieved a weak security CPA security and were not practical. Few works are focused on strong security CCA security which is left as an open problem. In this paper, we solve this problem and construct directly a CCA secure ABE. For the sake of realizing this target, a CPA secure scheme is introduced at first. Based on this basic scheme, a l leakage resilient CCA2 secure ABE is proposed in the standard model. It tolerates up to (log p o(log k) bit leakage of the private key and its leakage parameter is independent of the message length, where k is the security parameter and p is the prime order of the underlying group. Additionally, the proposed scheme is efficient and practical over the available, where the private keys are constant and independent of depth of attributes of the users. It also achieves anonymity and full security.
Int. J. Netw. Secur.