Generalized Hierarchical Identity-Based Signcryption

Abstract

In this paper, we propose a generic method to construct Hierarchical Identity-Based Signcryption scheme. Using this method, a Hierarchical Identity-Based Signcryption scheme can be converted from any Hierarchical Identity-Based Encryption scheme. Then, we give a concrete instantiation, which is the first constant-size fully secure hierarchical identity-based signcryption scheme in the standard model. Furthermore, our scheme can achieve CCA2 security level without using any additional cryptography primitive.