Cryptology ePrint Archive: Report 2020/1230

Certificateless Public-key Authenticate Encryption with Keyword Search Revised: MCI and MTP

Leixiao Cheng and Fei Meng

Abstract: Boneh et al proposed the cryptographic primitive public key encryption with keyword search (PEKS) to search on encrypted data without exposing the privacy of the keyword. Most standard PEKS schemes are vulnerable to inside keyword guessing attacks (KGA), i.e., a malicious server may generate a ciphertext by its own and then to guess the keyword of the trapdoor by testing. Huang et al. solved this problem by proposing the public-key authenticated encryption with keyword search (PAEKS) achieving single trapdoor privacy (TP). Qin et al. defined notion of multi-ciphertext indistinguishability (MCI) security and multi-trapdoor privacy (MTP) security, and proposed the first PAEKS scheme with MCI and TP.

Certificateless public-key authenticated encryption with keyword search (CLPAEKS) is first formally proposed by He et al. as combination of the PAEKS and the certificateless public key cryptography (CLPKC). Lin et al. revised He's work and re-formalize the security requirements for CLPAEKS in terms of trapdoor privacy and ciphertext indistinguishability. However, how to achieve both MCI and MTP security in a CLPAEKS scheme is still unknown.

In this paper, we initially propose a CLPAEKS scheme with both MCI security and MTP security simultaneously. We provide formal proof of our schemes in the random oracle model.

Category / Keywords: public-key cryptography / Certificateless Public key encryption, Keyword search, Keyword guessing attacks, Multi-ciphertext indistinguishability, Multi-trapdoor privacy

Date: received 6 Oct 2020, last revised 21 Dec 2020

Contact author: mengfei_sdu at 163 com

Available format(s): PDF | BibTeX Citation

Version: 20201221:150522 (All versions of this report)

Short URL: ia.cr/2020/1230