一种针对PRESENT的改进旁路Cube分析方法

对PRESENT-80旁路Cube攻击进行了改进．基于第3轮单比特泄漏模型，在现有寻找密钥相关线性等式的基础上，通过获取非线性等式方法恢复出更多密钥位．实验结果表明：针对第1个s盒的第1位信息泄漏，2^7.67个选择明文即可恢复40位密钥，优于现有的32位；针对第2，3，4个S盒的第1位信息泄漏，2^12.147个选择明文即可恢复64位密钥，优于现有的48位，将密钥搜索空间降低到2^16．此外，本方法可适用于PRESENT-128及其它轻型分组密码旁路Cube分析．

An Improved Method of Side-Channel Cube Analysis on PRESENT

This paper proposes an improved side-channel cube attack on PRESENT-80. Based on the single bit leakage model in round 3, this paper extracts the non-linear key related equations in addition to the linear ones by previous works, and can recover more key bits. Experiment results show that,as to the first output bit leakage of the first S-Box,2^7.67 chosen plaintexts can recover 40 key bits,which is more than 32 bits in previous works;as to the first output bit leakage of the second,third,fourth S-Box,2^12.147 chosen plaintexts can extract 64-bit key bits and reduce the key search space of PRESENT-80 to 2^16 , which is better than 48 bits in previous works. The improved SCCA method of this paper can also be applied to PRESENT-128 or other lightweight block ciphers.