Design and optimization of stream cipher-oriented AIC structure-based Boolean function unit
Zhaoxu Zhou, Zongren Zhang, Zibin Dai, Yanjiang Liu, Junwei Li · IET conference proceedings. · 2025
Stream ciphers are widely used in information security. As their core components, the efficiency of hardware implementation of Boolean functions directly affects the performance of cryptographic algorithms. Existing implementation schemes based on FPGA or LUT suffer from issues such as insufficient performance, resource redundancy, or low utilization, making it difficult to balance flexibility and efficiency. Through statistical analysis of 46 Boolean functions in 32 stream cipher algorithms, this paper finds that their product terms are mainly of degree 5 or lower, there exist specific distribution characteristics between input variables and shift register bit widths, and the LUT structure is incompatible with the reconfigurable requirements of Boolean function. To address these issues, this paper proposes replacing LUT with a NAND cone structure and designing a 96-bit Boolean function operation unit based on 5-AIC structure. This scheme can accurately match the structural characteristics of Boolean functions and shows significant advantages in key indicators such as area and delay, providing a feasible path for the efficient hardware implementation of Boolean function in stream ciphers.