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Making Large Hash Functions From Small Compression Functions

Authors:
William R. Speirs
Ian Molloy
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URL: http://eprint.iacr.org/2007/239
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Abstract: We explore the idea of creating a hash function that produces an $s$-bit digest from a compression function with an $n$-bit output, where $s > n$. % where $s\le 2^{n/2}n$.This is accomplished by truncating a hash function with a digest size of $\ell n$-bits. Our work answers the question of how large $\ell$ can be while creating a digest of $sn$-bits securely. We prove that our construction is secure with respect to preimage resistance and collision resistance for $s \le 2^{n/2}n$.
BibTeX
@misc{eprint-2007-13520,
  title={Making Large Hash Functions From Small Compression Functions},
  booktitle={IACR Eprint archive},
  keywords={foundations / hash functions},
  url={http://eprint.iacr.org/2007/239},
  note={Work in progress bill.speirs@gmail.com 13680 received 15 Jun 2007},
  author={William R. Speirs and Ian Molloy},
  year=2007
}