三类循环移位变换对旋转攻击的影响

Effects of three kinds of cyclic shift transformation to rotational attack

针对三类循环移位变换对旋转攻击性能的影响进行了研究,利用概率知识证明了等字间的循环移位变换不影响旋转攻击的攻击方式和效率,给出了多字间的循环移位变换和子字间的循环移位变换影响旋转攻击的概率公式,并由此得出当取旋转数r=1时能使旋转攻击最大限度地通过相应的循环移位变换。

This paper studied three kinds of circle shift transformation effect on the performance of rotational attack, using probability knowledge proved that the equal-word circle shift transformation had no influence on the attack mode and efficiency of rotational attack. It presented influence probability formulas on rotational attack of the longer-word circle shift transformation and the shorter-word circle shift transformation. These formulas show that if the rotational amount r is set to 1 the corresponding circle shift transformation preserves the rotational property at most.