Paper 2007/292

Improved security analysis of OMAC

Mridul Nandi

Abstract

We present an improved security analysis of OMAC, the construction is widely used as a candidate of MAC or Pseudo Random Function (or PRF). In this direction, the first result was given in Crypto-05 where an improved security analysis of CBC (for fixed length or for arbitrary length prefix-free messages) had provided. Followed by this work, improved bounds for XCBC, TMAC and PMAC were found. The improved bounds are of the form where the original bounds are which is roughly . Here, a distinguisher can make at most queries having at most many blocks with as the maximum block size. The original bound for OMAC was roughly shown in FSE-03 and the next improved bound was shown in Indocrypt-03. In this paper we have provided an improved bound (a similar form as provided for others) for OMAC and the bound we show is roughly .

Metadata
Available format(s)
PDF
Category
Secret-key cryptography
Publication info
Published elsewhere. Unknown where it was published
Contact author(s)
mridul nandi @ gmail com
History
2007-08-07: received
Short URL
https://ia.cr/2007/292
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2007/292,
      author = {Mridul Nandi},
      title = {Improved security analysis of {OMAC}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2007/292},
      year = {2007},
      url = {https://eprint.iacr.org/2007/292}
}
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.