Development of a Pseudo-Random Sequence Generation Function Based on the Cryptographic Algorithm "Kuznechik"

The paper deals with the main component of a deterministic random sequence generator – a generation function based on the algorithm "Kuznechik" (Russian encryption standard GOST R 34.12-2015). A procedure of round keys generation that uses the features of the algorithm has been developed. It allows to use the algorithm in a mode that combines the advantages of well-known OFB and CTR encryption modes. In addition, some enhancements of the algorithm that improve the generator security while maintaining its performance are implemented. The quality of the generator was evaluated by means of statistical tests (NIST SP 800-22), Pear-son's criterion, and min-entropy (NIST 800-90B tests). According to the analyzed characteristics, the enhanced generator and its ordinary version based on "Kuznechik" algorithm are comparable, but the proposed generation function has a higher security level.