Cryptology ePrint Archive: Report 2018/1180

Lattice-Based Signature from Key Consensus

Leixiao Cheng and Boru Gong and Yunlei Zhao

Abstract: In this work, we present generalization and optimization of Dilithium, which is one of the promising lattice-based signature candidates for NIST postquantum cryptography (PQC) standardization. This is enabled by new insights in interpreting the design of Dilithium, in terms of key consensus presented in the KCL key encapsulation mechanism (KEM) proposal to NIST PQC standardization. Based on OKCN developed in KCL, we present a generic and modular construction of lattice-based signature, and make analysis as it is deployed in reality. We thoroughly search and test a large set of parameters in order to achieve better trade-offs among security, efficiency, and bandwidth. On the recommended parameters for about 128-bit quantum security, compared with Dilithium, our scheme is more efficient both in computation and in bandwidth. This work also further justifies and highlights the desirability of OKCN as the same routine can be used for both KEM and signatures, which is useful to simplify system complexity of lattice-based cryptography. Of independent interest is a new estimation of the security against key recovery attacks in reality.

Category / Keywords: public-key cryptography / post-quantum cryptography, lattice, signature, key consensus

Date: received 3 Dec 2018

Contact author: ylzhao at fudan edu cn

Available format(s): PDF | BibTeX Citation

Version: 20181205:143707 (All versions of this report)

Short URL: ia.cr/2018/1180


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