Protection method and device for white-box SM4 algorithm

• Main Authors: YIN JIAYUE, LI GUO, LI JIATIAN, CUI CHAO
• Format: Patent
• Language: Chinese; English
• Published: 08.08.2023
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION; WIRELESS COMMUNICATIONS NETWORKS

In order to solve the problems that an existing SM4 white box may be subjected to advanced attacks and has technical hidden dangers in security, the invention provides the white box SM4 algorithm protection method and device, random masks are introduced into a lookup table of a hidden key, and meanwhile, nonlinear coding is combined, so that the correlation between the key and a table lookup result in an encryption process is reduced, and the security of the white box is improved. The uncertainty of table look-up result output is increased, side channel attacks can be effectively resisted, and the problem of insufficient security in the prior art is solved. 针对现有SM4白盒可能会受到高级攻击，安全性存在技术隐患的问题，本发明提供了一种白盒SM4算法的防护方法及装置，在隐藏密钥的查找表中，引入了随机掩码，同时结合了非线性编码，降低了密钥与加密过程中查表结果之间的相关性，增加了查表结果输出的不确定性，可以有效抵抗侧信道攻击，解决现有技术安全性不够的问题。