Attribute-Based Signcryption from Lattices in the Standard Model

Abstract

For realizing the fine-grained access control with non-interactive approach, and effectively guaranteeing the comprehensive security for information under the post-quantum environment, this paper proposes an attribute-based signcryption (ABSC) scheme based on the intractability of lattices. The proposed ABSC scheme is proved indistinguishable against the inner adaptive-chosen ciphertext attacks (IND-CCA2) and existentially unforgeable against inner chosen-message attacks (EUF-CMA), in the standard model. The theoretical analysis presents that the public key size and the computational cost of the signcryption operation are both reduced obviously, compared with the signature and then encryption mechanism. An efficient variant is also presented that significantly decreases the computational complexity of unsigncryption operation at the expense of an increase in the ciphertext size.