Paper 2001/074
On the Security of Randomized CBC-MAC Beyond the Birthday Paradox Limit - A New Construction
Eliane Jaulmes, Antoine Joux, and Frederic Valette
Abstract
In this paper, we study the security of randomized CBC-MACs and propose a new construction that resists birthday paradox attacks and provably reaches full security. The size of the MAC tags in this construction is optimal, i.e., exactly twice the size of the block cipher. Up to a constant, the security of the proposed randomized CBC-MAC using an n-bit block cipher is the same as the security of the usual encrypted CBC-MAC using a 2n-bit block cipher. Moreover, this construction adds a negligible computational overhead compared to the cost of a plain, non-randomized CBC-MAC. We give a full standard proof of our construction using one pass of a block cipher with 2n-bit keys but there also is a proof for n-bit keys block ciphers in the ideal cipher model.
Note: This revision includes explanations on MAC truncation. The proof has also been slightly modified, changing the use of the random oracle model for the ideal cipher model.
Metadata
- Available format(s)
- PS
- Category
- Cryptographic protocols
- Publication info
- Published elsewhere. FSE 2002
- Keywords
- authentication codesblock ciphers
- Contact author(s)
- eliane jaulmes @ wanadoo fr
- History
- 2002-11-28: last of 2 revisions
- 2001-08-31: received
- See all versions
- Short URL
- https://ia.cr/2001/074
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2001/074,
author = {Eliane Jaulmes and Antoine Joux and Frederic Valette},
title = {On the Security of Randomized {CBC}-{MAC} Beyond the Birthday Paradox Limit - A New Construction},
howpublished = {Cryptology {ePrint} Archive, Paper 2001/074},
year = {2001},
url = {https://eprint.iacr.org/2001/074}
}
