基于MILP的ECLBC算法积分区分器搜索OA

ECLBC algorithm is a lightweight block cipher with SPN structure proposed by Guo et al.in 2024,which has error detection and error correction mechanism,and can realize the secure transmission of data,and has a broad application prospect in the field of Internet of Things(IoT).Integral analysis is a commonly used way of cryptanalysis,using the three-subset bit division property,combined with the MILP automated search tool,can be more accurate and effective to find the integral distinguisher.This study uses the MILP model to find the integral distinguisher based on the three-subset bit division for the block cipher ECLBC algorithm.It is worth noting that,in modelling the division of the nonlinear layer of the ECLBC algorithm,the"S-box"technique is used,where the nonlinear layer is regarded as the"S-box"layer,and in describing the propagation of the division of the S-box of the nonlinear operations,the"expand-and-reduce"technique is used,where the nonlinear layer is regarded as the"S-box"layer.In describing the propagation of the division property of the nonlinear S-box,the"expand-and-reduce"reduction algorithm is used to generate the corresponding inequality sets.Firstly,a larger set of inequalities is generated based on the original set of inequalities generated by the convex method.Secondly,a small and sufficient subset of inequalities is selected from the large set in the previous step.By proposed method,the number of linear inequalities propagated by the"S-box"division property of the ECLBC algorithm is greatly reduced.In addition,through cross propagation,the integral distinguisher for searching for the division property of three-subset of an algorithm with r rounds is transformed into solving r MILP models,and for the first time,a 9-round integral distinguisher is found for the ECLBC algorithm,which is one round more than the previous best result.