<abstract xmlns="http://www.w3.org/1999/xhtml"><p> Rotational cryptanalysis was introduced by Khovratovich and Nikoli ´c as a tool to analyse ARX-type cipher designs. GOST 28147-89 is a former Soviet Union cipher standard based on a Feistel construction with 32 rounds. Each round function adds the round key modulo 2<sup>32</sup>, transforms the result with 4-to-4 bit S-boxes, and rotates the output. We apply the rotational cryptanalysis to a version of GOST using eight identical S-boxes, such as GOST-PS. We show the existence of (practical) rotational distinguisher in related key model for full GOST. Furthermore, there is a set of weak keys (rotationally symmetric keys) that enables rotational attacks in single-key model as well. Finally, we show a simple attack on the last round that uses the rotational distinguisher to reduce the complexity of the full GOST to 208 bits.</p></abstract>

Rotational cryptanalysis was introduced by Khovratovich and Nikoli ´c as a tool to analyse ARX-type cipher designs. GOST 28147-89 is a former Soviet Union cipher standard based on a Feistel construction with 32 rounds. Each round function adds the round key modulo 232, transforms the result with 4-to-4 bit S-boxes, and rotates the output. We apply the rotational cryptanalysis to a version of GOST using eight identical S-boxes, such as GOST-PS. We show the existence of (practical) rotational distinguisher in related key model for full GOST. Furthermore, there is a set of weak keys (rotationally symmetric keys) that enables rotational attacks in single-key model as well. Finally, we show a simple attack on the last round that uses the rotational distinguisher to reduce the complexity of the full GOST to 208 bits.

ROTATIONAL CRYPTANALYSIS OF GOST WITH IDENTICAL S-BOXES

Institute of Computer Science and Mathematics, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology in Bratislava Ilkoviˇcova 3 SK–812-19 Bratislava, SLOVAKIA

Institute of Computer Science and Mathematics, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology in Bratislava Ilkoviˇcova 3 ,SK–812-19 Bratislava, SLOVAKIA

Tatra Mountains Mathematical Publications

{"article-title":"ROTATIONAL CRYPTANALYSIS OF GOST WITH IDENTICAL S-BOXES"}

Rotational cryptanalysis was introduced by Khovratovich and Nikoli ´c as a tool to analyse ARX-type cipher designs. GOST 28147-89 is a former Soviet Union...

ROTATIONAL CRYPTANALYSIS OF GOST WITH IDENTICAL S-BOXES

Publicado en línea: 18 feb 2014

Páginas: 1 - 19

DOI: https://doi.org/10.2478/tmmp-2013-0032

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