OMAC: One-Key CBC MAC

Tetsu Iwata; Kaoru Kurosawa

Paper 2002/180

OMAC: One-Key CBC MAC

Tetsu Iwata and Kaoru Kurosawa

Abstract

In this paper, we present One-key CBC MAC (OMAC) and prove its security for arbitrary length messages. OMAC takes only one key, $K$ ($k$ bits) of a block cipher $E$. Previously, XCBC requires three keys, $(k+2n)$ bits in total, and TMAC requires two keys, $(k+n)$ bits in total, where $n$ denotes the block length of $E$. The saving of the key length makes the security proof of OMAC substantially harder than those of XCBC and TMAC.

Metadata

Available format(s): PDF PS
Category: Secret-key cryptography
Publication info: Published elsewhere. Pre-proceedings of FSE 2003
Keywords: CBC MAC block cipher provable security
Contact author(s): iwata @ cis ibaraki ac jp
History: 2003-03-10: revised; 2002-12-01: received; See all versions
Short URL: https://ia.cr/2002/180
License: CC BY

BibTeX

@misc{cryptoeprint:2002/180,
      author = {Tetsu Iwata and Kaoru Kurosawa},
      title = {{OMAC}: One-Key {CBC} {MAC}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2002/180},
      year = {2002},
      url = {https://eprint.iacr.org/2002/180}
}