一类广义多项式函数的可逆性的判定

A Criterion for a Class of Generalized Polynomials'invertibility

多项式函数作为一类密码学中常用的T函数,其可逆性质的判定是相关研究中的重要问题。利用p-adic的乘法公式给出了广义多项式函数p(x)=a0+a1x+…+adxd(modpn)(其中p为任意素数)是可逆的充要条件。

The investigation of the invertibility of polynomial functions as a class of commonly used T func- tions in cryptography is an important research problem. According to the p-adic multiplication formula , the necessary and sufficient condition on the invertibility of the generalized polynomial function （p is any prime） is given.