Paper 2023/1355
Security Proofs for Key-Alternating Ciphers with Non-Independent Round Permutations
, Shanghai Jiao Tong University, Shanghai Qi Zhi Institute, East China Normal UniversityAbstract
This work studies the key-alternating ciphers (KACs) whose round permutations are not necessarily independent. We revisit existing security proofs for key-alternating ciphers with a single permutation (KACSPs), and extend their method to an arbitrary number of rounds. In particular, we propose new techniques that can significantly simplify the proofs, and also remove two unnatural restrictions in the known security bound of 3-round KACSP (Wu et al., Asiacrypt 2020). With these techniques, we prove the first tight security bound for t-round KACSP, which was an open problem. We stress that our techniques apply to all variants of KACs with non-independent round permutations, as well as to the standard KACs.
Metadata
- Available format(s)
-
PDF
- Category
- Secret-key cryptography
- Publication info
- A major revision of an IACR publication in TCC 2023
- Keywords
- provable securitykey-alternating cipherKACSPindistinguishabilityrandom permutation modelnon-independent
- Contact author(s)
-
lqyups @ 126 com
yusaiwu @ 126 com
yuyu @ yuyu hk
zfcao @ sei ecnu edu cn
dong-xl @ sei ecnu edu cn - History
- 2023-09-13: approved
- 2023-09-11: received
- See all versions
- Short URL
- https://ia.cr/2023/1355
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2023/1355,
author = {Liqing Yu and Yusai Wu and Yu Yu and Zhenfu Cao and Xiaolei Dong},
title = {Security Proofs for Key-Alternating Ciphers with Non-Independent Round Permutations},
howpublished = {Cryptology {ePrint} Archive, Paper 2023/1355},
year = {2023},
url = {https://eprint.iacr.org/2023/1355}
}
