An Adaptively Secure Functional Encryption for Randomized Functions. (8th August 2020)

• Record Type: Journal Article
• Authors: Liu, Muhua; Zhang, Ping
• Is Part Of: Computer journal. Volume 63:Number 8(2020)
• Page Start: 1247
• Page End: 1258
• Publication Date: 2020-08-08
• Subjects: functional encryption -- indistinguishability obfuscation -- adaptive security -- randomized functions; Computers -- Periodicals; 005.1
• DOI: 10.1093/comjnl/bxz154
• Languages: English
• ISSNs: 0010-4620

Abstract

Abstract: Functional encryption (FE) can provide a fine-grained access control on the encrypted message. Therefore, it has been applied widely in security business. The previous works about functional encryptions most focused on the deterministic functions. The randomized algorithm has wide application, such as securely encryption algorithms against chosen ciphertext attack, privacy-aware auditing. Based on this, FE for randomized functions was proposed. The existing constructions are provided in a weaker selective security model, where the adversary is forced to output the challenge message before the start of experiment. This security is not enough in some scenes. In this work, we present a novel construction for FE, which supports the randomized functionalities. We use the technology of key encapsulated mechanism to achieve adaptive security under the simulated environment, where the adversary is allowed to adaptively choose the challenge message at any point in time. Our construction is built based on indistinguishability obfuscation, non-interactive witness indistinguishable proofs and perfectly binding commitment scheme.