Paper 2010/566 Original: eprint.iacr.org/2010/566 ↗
Blockcipher-based Double-length Hash Functions for Pseudorandom Oracles
Abstract
The notion of PRO (pseudorandom oracle) is an important security notion of hash functions because a PRO hash function inherits all properties of a random oracle up to the PRO bound (e.g., security against generic attacks, collision resistant security, preimage resistant security and so on). In this paper, we propose a new block cipher-based double-length hash function for PROs. Our hash function uses a single block cipher, which encrypts an $n$-bit string using a $2n$-bit key, and maps an input of arbitrary length to a $2n$-bit output. Since many block ciphers supports a $2n$-bit key (e.g. AES supports a $256$-bit key), the assumption to use the $2n$-bit key length block cipher is acceptable. We prove that our hash function is PRO up to $\order(2^n)$ query complexity as long as the block cipher is an ideal cipher. To our knowledge, this is the first time double-length hash function based on a single (practical size) block cipher with the birthday type PRO security.
Metadata
- Available format(s)
PDF- Category
- Secret-key cryptography
- Publication info
- Preprint.
- History
- 2011-05-11: last updated
- 2010-11-08: published
- Short URL
- https://ia.cr/2010/566
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2010/566,
author = {Yusuke Naito},
title = {Blockcipher-based Double-length Hash Functions for Pseudorandom Oracles},
howpublished = {Cryptology {ePrint} Archive, Paper 2010/566},
year = {2010},
url = {https://eprint.iacr.org/2010/566}
}