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arXiv · 1509.02584

XCRUSH: A Family of ARX Block Ciphers

Evan Saulpaugh
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Abstract

The XCRUSH family of non-Feistel, ARX block ciphers is designed to make efficient use of modern 64-bit general-purpose processors using a small number of encryption rounds which are simple to implement in software. The avalanche function, which applies one data-dependent, key-dependent rotation per 64-bit word of plaintext per round, allows XCRUSH to achieve an almost totally diffuse 256-bit block after just the first two rounds. Designed for speed in software, 3-round XCRUSH is measured at ~7.3 cycles/byte single-threaded on an Intel Haswell processor. A pseudorandom number generator, constructed using the avalanche function, serves as a key scheduling algorithm. No security claims are made in this paper.

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Evan Saulpaugh. 2015-09-09. XCRUSH: A Family of ARX Block Ciphers. https://arxiv.org/abs/1509.02584

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