Efficient Generic Construction of CCA-Secure Identity-Based Encryption from Randomness Extraction.

JOONSANG BAEK; WONG, DUNCAN S.; JIN LI; MAN HO AU

We propose a generic construction that yields efficient identity-based encryption (IBE) schemes secure against chosen ciphertext attack (CCA) in the standard model. Our construction extends Kiltz et al.'s (Eurocrypt '09) method of constructing CCA-secure public-key encryption schemes via randomness extraction to the identity-based setting. The main idea of our construction is to transform 'ϵ1ϵ1-almost κκ-entropic' and valid/invalid ciphertext indistinguishable (VI-IND) identity-based hash proof system to the one that satisfies the stronger 'ϵ2ϵ2-universal' and VI-IND property. This transformation is realized by a randomness extractor based on the 4-wise hash function. We demonstrate that our generic construction can produce CCA-secure IBE schemes whose efficiency is comparable with the most efficient but non-generic CCA-secure IBE schemes without random oracles in the literature.

CIPHERS; DATA encryption; PUBLIC key cryptography; DATA extraction; ENCRYPTION protocols

Computer Journal, 2016, Vol 59, Issue 4, p508

0010-4620

Academic Journal

10.1093/comjnl/bxv070