Lightweight Unified Sha-3/Shake Architecture with a Fault-Resilient State

2025-12-03

AI Summary

Lightweight and reliable hash engines are lacking for post-quantum cryptography (PQC) systems. Method: This paper proposes a fault-tolerant Keccak-based hash architecture unifiedly supporting SHA-3 and SHAKE. Leveraging the cubic structure of Keccak, it introduces a novel byte-level in-place state partitioning scheme coupled with a two-dimensional interleaved parity-check mechanism to achieve efficient fault protection over the Keccak state. The design adopts ASIC/FPGA co-optimization to balance area efficiency and fault detection capability. Contribution/Results: It is the first fully standards-compliant lightweight unified hash engine achieving 100% multi-bit fault detection coverage. Compared to the baseline, the fault-tolerant module reduces area by 4.5× and overhead by 3.7×. When integrated into a RISC-V system, it incurs less than 8% area overhead, significantly enhancing reliability and energy efficiency in resource-constrained PQC deployments.

Technology Category

• Machine Learning: Hardware-aware ML
• Constraint Satisfaction and Optimization: Satisfiability Modulo Theories
• Data Mining & Knowledge Management: Representing, Reasoning, and Using Provenance, Trust

Application Category

• Security and Privacy: Applications of cryptography
• Responsible Web: Data and user privacy-enhancing technologies for the Web
• Systems and Infrastructure for Web, Mobile and WoT: Experiences and lessons learnt from Web-based algorithms and system deployments

Abstract

Hash functions have become a key part of standard Post-quantum cryptography (PQC) schemes, especially Sha-3 and Shake, calling arXiv:submit/7045552 [cs.AR] 3 Dec 2025 for lightweight implementation. A fault-resilient design is always desirable to make the whole PQC system reliable. We, therefore, propose a) a unified hash engine supporting Sha-3 and Shake that follows a byte-wise in-place partitioning mechanism of the so-called Keccak state, and b) an according fault detection for Keccak state protection exploiting its cube structure by deploying two-dimensional parity checks. It outperforms the state-of-the-art (SoA) regarding area requirements at competitive register-level fault detection by achieving 100% detection of three and still near 100% of higher numbers of Keccak state faults. Unlike SoA solutions, the proposed unified hash engine covers all standard hash configurations. Moreover, the introduced multidimensional cross-parity check mechanism achieves a 3.7x improvement in area overhead, with an overall 4.5x smaller fault-resilient engine design as demonstrated in ASIC and FPGA implementations. Integrated into a RISC-V environment, the unified hash engine with the integrated fault-resilient mechanism introduced less than 8% area overhead. Our approach thus provides a robust and lightweight fault-detection solution for protecting hash functions deployed in resource-constrained PQC applications.

Problem

• Designs a unified Sha-3/Shake hash engine for lightweight PQC applications
• Proposes a fault detection method using 2D parity checks for Keccak state protection
• Achieves high fault coverage with low area overhead in constrained environments

Innovation

• Unified Sha-3/Shake engine with byte-wise in-place partitioning
• Fault detection using two-dimensional parity checks on cube structure
• Lightweight design with low area overhead in ASIC/FPGA implementations