计算机工程与应用 ›› 2012, Vol. 48 ›› Issue (16): 1-4.

• 博士论坛 • 上一篇    下一篇

LBlock中间状态的代数表示及其侧信道攻击

彭昌勇1,2,祝跃飞1,黄晓英2,康  绯1,滕吉红2   

  1. 1.解放军信息工程大学 信息工程学院,郑州 450002
    2.解放军信息工程大学 理学院,郑州 450002
  • 出版日期:2012-06-01 发布日期:2012-06-01

Algebraic expressions of LBlock middle state and side channel attack on LBlock

PENG Changyong1,2, ZHU Yuefei1, HUANG Xiaoying2, KANG Fei1, TENG Jihong2   

  1. 1.Institute of Information Engineering, Information Engineering University, Zhengzhou 450002, China
    2.School of Science, Information Engineering University, Zhengzhou 450002, China
  • Online:2012-06-01 Published:2012-06-01

摘要: LBlock是吴文玲和张蕾在ACNS2011上提出的轻量级分组密码,目前未见对该体制的公开的密码分析文章。用符号计算软件Mathematica 7.0得到了LBlock第三轮输出的最低比特的代数表达式(以明文和主密钥比特为自变量)。该代数表达式只与8比特密钥和9比特明文有关,可以用于对LBlock在单比特泄露模型下的侧信道攻击。模拟实验表明,假设第三轮输出的最低比特泄露,则用8个已知明文,85%的概率下可以恢复6~7比特密钥。

关键词: 鲁班锁分组密码, 分组密码, 符号计算, 侧信道攻击

Abstract: LBlock is a lightweight block cipher proposed by Wu Wenling and Zhang Lei at ACNS2011, with no public cryptanalysis articles until now. The algebraic expression(in terms of the plaintext bits and master key bits) of the Least Significant Bit(LSB) of the third round output is obtained by using the symbolic computation software Mathematica 7.0. The algebraic expression is only dependent on 8 key bits and 9 plaintext bits and can be used to mount a side channel attack on LBlock under the single bit leakage model. The simulation experiments show that with the LSB of the third round output leakaged, with 8 known plaintexts, 6~7 key bits can be recovered with probability 85%.

Key words: LBlock, block cipher, symbolic computation, side channel attack