On the Sixth International Olympiad in Cryptography NSUCRYPTO

Abstract

NSUCRYPTO is the unique cryptographic Olympiad containing scientific mathematical problems for professionals, school and university students from any country. Its aim is to involve young researchers in solving curious and tough scientific problems of modern cryptography. From the very beginning, the concept of the Olympiad was not to focus on solving olympic tasks but on including unsolved research problems at the intersection of mathematics and cryptography. The Olympiad history starts in 2014. In 2019, it was held for the sixth time. We present the problems and their solutions of the Sixth International Olympiad in cryptography NSUCRYPTO \(^{\prime} \)2019. Under consideration are the problems related to attacks on ciphers and hash functions, protocols, Boolean functions, Dickson polynomials, prime numbers, rotor machines, etc. We discuss several open problems on mathematical countermeasures to side-channel attacks, APN involutions, S-boxes, etc. The problem of finding a collision for the hash function Curl27 was partially solved during the Olympiad.

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Funding

The work of the first two authors and the sixth author was supported by the Mathematical Center in Akademgorodok under Agreement No. 075–15–2019–1613 with the Ministry of Science and Higher Education of the Russian Federation and the Laboratory of Cryptography JetBrains Research. The work of the fifth author was supported by the State Task to the Sobolev Institute of Mathematics (project no. 0314–2019–0016). The work of the seventh, eighth, and eleventh authors was supported by the Russian Foundation for Basic Research (projects nos. 20–31–70043, 18–07–01394, and 19–31–90093).

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Correspondence to A. A. Gorodilova or N. N. Tokareva or S. V. Agievich or C. Carlet or E. V. Gorkunov or V. A. Idrisova or N. A. Kolomeec or A. V. Kutsenko or R. K. Lebedev or S. Nikova or A. K. Oblaukhov or I. A. Pankratova or M. A. Pudovkina or V. Rijmen or A. N. Udovenko.

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Translated by A. Gorodilova

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Gorodilova, A.A., Tokareva, N.N., Agievich, S.V. et al. On the Sixth International Olympiad in Cryptography NSUCRYPTO. J. Appl. Ind. Math. 14, 623–647 (2020). https://doi.org/10.1134/S1990478920040031

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Keywords

  • cryptography
  • cipher
  • hash function
  • Hamming code
  • slide attack
  • threshold implementation
  • Dickson polynomial
  • APN function
  • Olympiad
  • NSUCRYPTO