针对传统Hash算法有安全缺陷的问题,利用有限域上多变量二次方程组求解(MQ)问题的困难性,设计了一种新的基于有限域上多变量二次多项式的Hash算法.新算法给出了一个改进的M-D结构,采用了NMAC(nested MAC)的思想,并加入了计数器,旨在抵抗一些针对传统M-D结构的攻击.新算法具有可调的输出参数,可以适应不同程度的安全性需求.新算法可以抵抗常见的攻击,且具有良好的雪崩效应.新算法相对于以往的多变量Hash算法,在内存需求上和运行速度上都有一定的优势.
As there are some security defects in traditional Hash algorithms,a new Hash algorithm was proposed.This algorithm's security was based on the difficulty of solving large systems of quadratic multivariate polynomial equations over a finite field.An improved Merkle-Damgrd construction was proposed,and Nested MAC's idea was used in the new Hash algorithm;a counter was also added in the construction to resist some attacks to the Merkle-Damgrd construction.The output size of the new Hash algorithm is adjustable,aiming to provide different levels of security.The new Hash algorithm is secure against common attacks,and it exhibits a satisfactory avalanche effect.It also has some advantages in memory requirements and running speed compared with previous multivariate Hash algorithms.