Безключові геш-функції регістрового типу

Abstract

Keyless hash functions are one of the most important cryptographic primitives and are used in modern encryp­tion, authentication, digital signature, keys generation systems, etc. Although conspicuous progress in develop­ing of various attacks on specific hash functions, under­standing of the principles underlying these attacks, deter­mining the conditions of their applicability, and develop­ment of methods for their performance estimating is an active subject of further research. The goal of this paper is to establish the general conditions of practical security for a broad class of hash functions based on shift registers against collision search attacks on their compression func­tions. It is shown that the problem of building of colli­sions can be reduced to solving some automaton equa­tions with binary unknowns satisfying certain constraints. Then the set of all solutions of these equations (without constraints) have simple algorithmic description that al­lows to enumerate these solutions in the real time-mode.