Hidden attribute‐based signcryption scheme for lattice

Abstract

As a novel cryptographic primitive, signcryption realizes the function of digital signature and public‐key encryption simultaneously, at a cost significantly lower than that of the traditional sign‐then‐encrypt approach. To the best of the authors’ knowledge, there is little works focusing on attribute‐based signcryption (ABSC), especially in the setting of lattice‐based cryptography. In this paper, we show that it is possible to construct hidden ABSC schemes based on lattice problems by presenting an ABSC scheme. In the random oracle model, the proposed scheme is proved to be indistinguishable against adaptively chosen ciphertext attacks under the learning with errors assumption and existentially unforgeable against adaptively chosen message attacks under the short integer solution assumption, respectively. Copyright © 2013 John Wiley & Sons, Ltd.

Improved Lattice-Based Signcryption in the Standard Model

“…In [13], Lu et al used Boyen's SUF-ACMA secure signature [14] and broke the malleability of ciphertext by adopting the bimode encryption method. Xiang et al [15] designed an attribute-based signcryption scheme from a lattice in the ROM. Lu et al [16] constructed an IND-CPA secure signcryption scheme based on a signature without a trapdoor [17] and strengthened the scheme to IND-CCA2 secure signcryption in the ROM by employing Fujisaki-Okamoto's transformation technique [18].…”

Attribute-Based Signcryption From Lattices in the Standard Model

“…For defining the confidentiality of an ABSC scheme, we give Game IND-sAtt-CCA2 between the challenger and a probabilistic polynomial time (PPT) adversary as follows, by referring to [1], [8].…”

“…However, the ciphertexts are generated also according to attributes. As a result, this scheme [8] cannot express the access policy well and does not enjoy the flexibility of the policy. Therefore, it has an important theoretical and practical significance to construct a true ABSC scheme based on lattice.…”

“…The ABE is divided into ciphertext policy attributebased encryption (CP-ABE) and key policy attribute-based encryption (KP-ABE), according to the difference that the policy is imposed upon ciphertext and private key. Indeed, ABSC recently has been extensively studied and many fruits [1]- [4], [8]- [10] have been obtained.…”

“…It is very flexible to be used to realize some complex cryptographic primitives and tools such as fully homomorphic encryption [13]- [17], fully homomorphic signature [18], [19] and multilinear map [20], [21]. Xiang et al [8] made a progress to construct an ABSC scheme based on lattice by conferring private keys according to attributes. However, the ciphertexts are generated also according to attributes.…”