QCCA-Secure Generic Transformations in the Quantum Random Oracle Model

Tianshu Shan; Jiangxia Ge; Rui Xue

Paper 2022/1235

QCCA-Secure Generic Transformations in the Quantum Random Oracle Model

Tianshu Shan

, State Key Laboratory of Information Security, Institute of Information Engineering, Chinese Academy of Sciences, Beijing, China, School of Cyber Security, University of Chinese Academy of Sciences, Beijing, China

Jiangxia Ge

, State Key Laboratory of Information Security, Institute of Information Engineering, Chinese Academy of Sciences, Beijing, China, School of Cyber Security, University of Chinese Academy of Sciences, Beijing, China

Rui Xue

, State Key Laboratory of Information Security, Institute of Information Engineering, Chinese Academy of Sciences, Beijing, China, School of Cyber Security, University of Chinese Academy of Sciences, Beijing, China

Abstract

The post-quantum security of cryptographic schemes assumes that the quantum adversary only receives the classical result of computations with the secret key. Further, it is unknown whether the post-quantum secure schemes still remain secure if the adversary can obtain a superposition state of the results. In this paper, we formalize one class of public-key encryption schemes named oracle-masked schemes. Then we define the plaintext extraction procedure for those schemes and this procedure simulates the quantum-accessible decryption oracle with a certain loss. The construction of the plaintext extraction procedure does not need to take the secret key as input. Based on this property, we prove the IND-qCCA security of the Fujisaki-Okamoto (FO) transformation in the quantum random oracle model (QROM) and our security proof is tighter than the proof given by Zhandry (Crypto 2019). We also give the first IND-qCCA security proof of the REACT transformation in the QROM. Furthermore, our formalization can be applied to prove the IND-qCCA security of key encapsulation mechanisms with explicit rejection. As an example, we present the IND-qCCA security proof of $\textsf{T}_{\textsf{CH}}$ transformation, proposed by Huguenin-Dumittan and Vaudenay (Eurocrypt 2022), in the QROM.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: A minor revision of an IACR publication in PKC 2023
Keywords: FO transformation REACT transformation quantum random oracle model quantum chosen ciphertext security
Contact author(s): shantianshu @ iie ac cn
gejiangxia @ iie ac cn
xuerui @ iie ac cn
History: 2023-02-17: revised; 2022-09-17: received; See all versions
Short URL: https://ia.cr/2022/1235
License: CC BY

BibTeX

@misc{cryptoeprint:2022/1235,
      author = {Tianshu Shan and Jiangxia Ge and Rui Xue},
      title = {QCCA-Secure Generic Transformations in the Quantum Random Oracle Model},
      howpublished = {Cryptology ePrint Archive, Paper 2022/1235},
      year = {2022},
      note = {\url{https://eprint.iacr.org/2022/1235}},
      url = {https://eprint.iacr.org/2022/1235}
}