Improved White-box SM4 Design and Implementation

• DOI: 10.1145/3650400.3650612
• Publication Date: 2024-04-17T12:33:18Z
• Authors: Yanjun Li; Xinjie Bi; Xiaoyu Jing; Zexiao Zou; Long Yang
• Keywords: S-box; White box

SM4, as a block cipher standard in China, has received extensive attention since the date of its publication. Its implementation correctness and security have rapidly become research hotspot. With popularity cryptographic algorithms network security, attack methods such key whitening attack, software static analysis, reverse engineering environment are also constantly developing. In order to resist these methods, white-box algorithm is required. Common schemes add large number linear or nonlinear transformations, which greatly reduces efficiency while enhancing security. this paper, we optimized design method Xiao-Lai SM4 algorithm. According structural characteristics, reduced one affine transformation increased encoding without disclosing relevant information intermediate data. Also, our work distinguished first, last rounds. We operated simulation implementation, significantly improved. Then diversity ambiguity scheme calculated, proves After tests, encryption speed improved by 18.6% decryption 20.8% compared with original scheme.