[Resource Topic] 2022/1444: Finding Three-Subset Division Property for Ciphers with Complex Linear Layers (Full Version)

Welcome to the resource topic for 2022/1444

Title:
Finding Three-Subset Division Property for Ciphers with Complex Linear Layers (Full Version)

Authors: Debasmita Chakraborty

Abstract:

Conventional bit-based division property (CBDP) and bit-
based division property using three subsets (BDPT) introduced by Todo
et al. at FSE 2016 are the most effective techniques for finding integral
characteristics of symmetric ciphers. At ASIACRYPT 2019, Wang et al.
proposed the idea of modeling the propagation of BDPT, and recently
Liu et al. described a model set method that characterized the BDPT
propagation. However, the linear layers of the block ciphers which are analyzed using the above two methods of BDPT propagation are restricted to simple bit permutation. Thus the feasibility of the MILP method of BDPT propagation to analyze ciphers with complex linear layers is not settled. In this paper, we focus on constructing an automatic search algorithm that can accurately characterize BDPT propagation for ciphers with complex linear layers. We first introduce BDPT propagation rule for the binary diffusion layer and model that propagation in MILP efficiently. The solutions to these inequalities are exact BDPT trails of the binary diffusion layer. Next, we propose a new algorithm that models Key-Xor operation in BDPT based on MILP technique. Based on these ideas, we construct an automatic search algorithm that accurately characterizes the BDPT propagation and we prove the correctness of our search algorithm. We demonstrate our model for the block ciphers with non-binary diffusion layers by decomposing the non-binary linear layer trivially by the COPY and XOR operations. Therefore, we apply our method to search integral distinguishers based on BDPT of SIMON, SIMON(102), PRINCE, MANTIS, PRIDE, and KLEIN block ciphers. For PRINCE and MANTIS, we find (2 + 2) and (3 + 3) round integral distinguishers respectively which are longest to date. We also improve the previous best integral distinguishers of PRIDE and KLEIN. For SIMON, SIMON(102), the integral distinguishers found by our method are consistent with the existing longest distinguishers.

ePrint: https://eprint.iacr.org/2022/1444

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .