A New Trapdoor-indistinguishable Public Key Encryption with Keyword Search

The public key encryption with keyword search (PEKS) provides a way for users to search data which are encrypted under the users’ public key on a storage system. However, the original schemes are based on the unrealistic assumption of a secure channel between the receiver and the server. Baek et al. [1] first proposed a secure channel-free public key encryption with keyword search (SCF-PEKS) to remove the assumption. However, Rhee et al. [2] point out that the SCF-PEKS scheme suffers from the keyword-guessing attack and proposed a scheme which satisfies the property of trapdoor indistinguishability without using an additional secure channel. In this paper, we construct a new efficient trapdoor-indistinguishable public key encryption with keyword search. Moreover, we prove that the proposed scheme can achieve the desired security properties.