A Comparison of Local Reduction and Sat-Solver Based Algebraic Cryptanalysis of Jh And Keccak

Abstract

ABSTRACT. Local reduction methods can be used to assess the resistance of cryptosystems against algebraic attacks. The assessment is based on the separation of the attack into polynomial-time reduction algorithm, and exponential time guessing and backtracking. This approach is similar to that employed by the DPLL algorithm that is used as a core of various modern SAT-solvers. In the article we show the application of this method to evaluate the strength of (reduced versions of) two chosen SHA-3 candidates: JH, and Keccak, respectively. We compare the complexity estimates with the behavior of the full search algorithm. We also compare the results based on the local reduction with the attack based on the use of SAT-solvers PrecoSAT, and CryptoMiniSAT, respectively.

Algebraic Cryptanalysis of Present Based on the Method of Syllogisms

“…If algorithm provides a reduced system with some redundant partial solutions and does not provide a solution, process can be continued with the introduction of guesses [1]. Guessing is used to estimate a value of some variable, e.g., x 1 = 0.…”

“…We say that system (1) is l-sparse. The main goal is to find a solution to (1). In order to use the method of syllogisms, the system of equations has to be rewritten to symbol representation.…”