Generic construction of public key encryption, identity-based encryption and signcryption with equality test

Public key encryption with equality test (PKEET) allows the cloud server to test whether two ciphertexts are generated on the same message. Recently, Lee et al. proposed a semi-generic approach for PKEET constructions by using the traditional public key encryption schemes. However, how to design a generic approach is still an open problem. In this paper, we propose a generic approach for PKEET constructions. Our approach can be easily extended to the identity-based setting. Compared with Lee et al.'s approach, ours is (surprisingly) more efficient. Moreover, we propose a new primitive, called signcryption with equality test (SCET). Compared with the traditional PKEET, SCET provides both confidentiality and authentication simultaneously.