NaSHA is a
hash function
A hash function is any function that can be used to map data of arbitrary size to fixed-size values. The values returned by a hash function are called ''hash values'', ''hash codes'', ''digests'', or simply ''hashes''. The values are usually ...
accepted as a first round SHA-3 candidate for the
NIST hash function competition
The NIST hash function competition was an open competition held by the US National Institute of Standards and Technology (NIST) to develop a new hash function called SHA-3 to complement the older SHA-1 and SHA-2. The competition was formally an ...
.
NaSHA was designed by
Smile Markovski
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Among humans, a smile expresses ...
and Aleksandra Mileva with contributions by Simona Samardziski (programmer) and Boro Jakimovski (programmer). NaSHA supports internal state sizes of 1024 and 2048 bits, and arbitrary output sizes between 125 and 512 bits. It uses
quasigroup
In mathematics, especially in abstract algebra, a quasigroup is an algebraic structure resembling a group in the sense that " division" is always possible. Quasigroups differ from groups mainly in that they need not be associative and need not have ...
string transformations with quasigroups of order 2
64, defined by extended Feistel networks.
[S. Markovski, A. Mileva. "Generating huge quasigroups from small non-linear bijections via extended Feistel function". In ''Quasigroups and Related Systems,'' vol. 17, 2009, pp. 91-106.] The quasigroups used in every iteration of the compression function are different and depend on the processed message block.
The authors claim performance of up to 23.06
cycles per byte
Encryption software is software that uses cryptography to prevent unauthorized access to digital information. Cryptography is used to protect digital information on computers as well as the digital information that is sent to other computers over t ...
on an Intel Core 2 Duo in 64-bit mode.
Cryptanalysis during the SHA-3 competition has indicated that 384/512 version of NaSHA is susceptible to
collision attack
In cryptography, a collision attack on a cryptographic hash tries to find two inputs producing the same hash value, i.e. a hash collision. This is in contrast to a preimage attack where a specific target hash value is specified.
There are roughl ...
s,
but the authors disputed those attacks and also included small changes to achieve the strength of 224/256 version.
References
External links
The official NaSHA websiteThe First Round SHA-3 candidates
NIST hash function competition
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