Post-quantum Security of OAEP Transform

Ehsan Ebrahimi

Paper 2021/237

Post-quantum Security of OAEP Transform

Ehsan Ebrahimi

Abstract

In this paper, we show that OAEP transform is indistinguishable under chosen ciphertext attack in the quantum random oracle model if the underlying trapdoor permutation is quantum partial-domain one-way. The existing post-quantum security of OAEP (TCC 2016-B ) requires a modification to the OAEP transform using an extra hash function. We prove the security of the OAEP transform without any modification and this answers an open question in one of the finalists of NIST competition, NTRU submission, affirmatively.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Preprint. MINOR revision.
Keywords: Post-quantum Security OAEP Quantum Random Oracle Model
Contact author(s): ehsan ebrahimi @ uni lu
History: 2021-07-20: revised; 2021-03-02: received; See all versions
Short URL: https://ia.cr/2021/237
License: CC BY

BibTeX

@misc{cryptoeprint:2021/237,
      author = {Ehsan Ebrahimi},
      title = {Post-quantum Security of OAEP Transform},
      howpublished = {Cryptology ePrint Archive, Paper 2021/237},
      year = {2021},
      note = {\url{https://eprint.iacr.org/2021/237}},
      url = {https://eprint.iacr.org/2021/237}
}