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Questions tagged [kalyna]

Kalyna is a symmetric block cipher. It supports block sizes of 128, 256 or 512 bits; the key length is either equal to or double the block size.

Kalyna was adopted as the national encryption standard of Ukraine in 2015 after holding Ukrainian national cryptographic competition. Kalyna is a substitution-permutation network and its design is based on the Rijndael (AES) encryption function having quite different key schedule, another set of four different S-boxes and increased MDS matrix size.

Kalyna has 10 rounds for 128-bit keys, 14 rounds for 256-bit keys and 18 rounds for 512-bit keys. Independent researchers proposed some attacks on reduced-round variants of Kalyna, but all of them have a very high complexity and none of them are practical.

Cipher specified in https://eprint.iacr.org/2015/650.pdf

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Is standardizing a modified AES a good idea?

"Recently" the Ukraine standardized a new block cipher Kalyna, which according to the abstract of"A New Encryption Standard of Ukraine: The Kalyna Block Cipher" by Oliynykov et al. (warning: the paper contains a lot of test-vectors) is basically a…
SEJPM
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Reverse Fixed Points in Kalyna S-Boxes and Reverse Engineering the S-Boxes

I was examining the S-Boxes of the Kalyna Cipher and found that 3 of the 4 S-boxes have reverse fixed points i.e S[x] = (255 - x). Is this an exploitable weakness? I was not able to find any open literature on how these S-Boxes were generated except…
vinu
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Is the cipher "Kalyna" with a 512-bit key length more secure AES with a 256-bit key?

Recently I have found out that Ukraine has its own symmetric encryption algorithm "Kalyna". Developers of this algorithm said that their algorithm is more secure than AES because of longer key length and lack of any vulnerabilities by hardware…
user55326
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Kalyna AddRoundKey

I don't understand how the AddRoundKey function works, because the following example is from the cipher authors. I'm trying to add $76$ and $7D$, and my result is $F3$. Could someone explain this? 8F 20 3E 06 5F C3 54 45 B5 FE B9 AC A7 A0 C6 76…
performance
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Can you point me to an MDS table reference for the Kalyna cipher?

I'm working with cipher Kalyna. Kalyna — like AES — has MDS tables in its MixColumns step. But Kalyna's documentation doesn't list these MDS tables. Could you give me a hint where to find proper documentation or the particular MDS tables?
Roman S.
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Does the security margin of Kalyna block cipher double per for additional 4 rounds? Would be possible to create a version of it with larger key sizes?

I believe this question should be directed to the authors of Kalyna block cipher, but I think they cannot answer me because of the war they are facing in their country actually. I know that AES uses this criteria for adjusting the rounds in accord…
phantomcraft
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