Paper 2021/288

Redeeming Reset Indifferentiability and Post-Quantum Groups

Mark Zhandry

Abstract

Indifferentiability is used to analyze the security of constructions of idealized objects, such as random oracles or ideal ciphers. Reset indifferentiability is a strengthening of plain indifferentiability which is applicable in far more scenarios, but is often considered too strong due to significant impossibility results. Our main results are: - Under weak reset indifferentiability, ideal ciphers imply (fixed size) random oracles and random oracle domain shrinkage is possible. We thus show that reset indifferentiability is more useful than previously thought. - We lift our analysis to the quantum setting showing that ideal ciphers imply random oracles under quantum indifferentiability. - Despite Shor's algorithm, we observe that generic groups are still meaningful quantumly, showing that they are quantumly (reset) indifferentiable from ideal ciphers; combined with the above, cryptographic groups yield post-quantum symmetric key cryptography. In particular, we obtain a plausible post-quantum random oracle that is a subset-product followed by two modular reductions.

Metadata
Available format(s)
PDF
Category
Secret-key cryptography
Publication info
Preprint. Minor revision.
Keywords
indifferentiabilityrandom oraclesideal ciphersquantum
Contact author(s)
mzhandry @ gmail com
History
2021-03-07: received
Short URL
https://ia.cr/2021/288
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2021/288,
      author = {Mark Zhandry},
      title = {Redeeming Reset Indifferentiability and Post-Quantum Groups},
      howpublished = {Cryptology ePrint Archive, Paper 2021/288},
      year = {2021},
      note = {\url{https://eprint.iacr.org/2021/288}},
      url = {https://eprint.iacr.org/2021/288}
}
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.