I am a researcher of cryptography at NTT Secure Platform Laboratories, NTT Corporation, Japan. I am also a doctoral course student at Nagoya University, supervised by Prof. Tetsu Iwata.
Contact e-mail adress: hosoyamada dot akinori at nagoya-u dot jp
Last update: September 25th, 2020
Research Interests and Hilights
Currently I am interested in symmetric-key cryptography, especially in post-quantum security of symmetric-key schemes, e.g., cryptanalysis of block ciphers and hash functions using quantum algorithms, and post-quantum security proofs for mode of operations. The following list is the highlight of my recent results with co-researchers.
- Impossibility of quantum fully-black-box reductions from collision-resistant hash functions to one-way permutations [HY20] (Best Paper Award @ Asiacrypt 2020).
- Dedicated quantum colilsion attacks on concrete hash functions [HS20].
- Quantum multicollision-finding algorithms for cryptgraphic hash functions [HSX17,HSTX19,HSTX20].
- Proof that the 4-round Luby-Rackoff construction (Feistel construction) is a quantum pseudo-random permutation [HI19].
- Quantum attack that takes advantage of Simon’s algorithm without quantum superposed queries to keyed oracles [BHNSS19].
- Proof for one-wayness of the combination of the Merkle-Damgaard construction with the Davies-Meyer construction against quantum adversaries [HY18].
So far most of my published results are related to post-quantum security of symmetric-key schemes, but I am also interested in other topics on cryptography both in the quantum and classical settings. (Basically I like pure/applied mathematics.)
Papers (in English)
See also dblp
Peer-Reviewed International Conference (with proceedings)
- [HY20] Hosoyamada, A., Yamakawa, T.: Finding Collisions in a Quantum World: Quantum Black-Box Separation of Collision-Resistance and One-Wayness. (To appear at ASIACRYPT 2020)(Best Paper Award) [Full ver. (IACR ePrint)]
- [HS20] Hosoyamada, A., Sasaki, Y.: Finding Hash Collisions with Quantum Computers by Using Differential Trails with Smaller Probability than Birthday Bound. (EUROCRYPT 2020) [Proceeding ver. (Springer LNCS)][Full ver. (IACR ePrint)]
- [HI19] Hosoyamada, A., Iwata, T.: 4-Round Luby-Rackoff Construction is a qPRP. (ASIACRYPT 2019) [Proceeding ver. (Springer LNCS)] [Full ver. (IACR ePrint)] (Note: A major revision is made after the conference. Please see the full version for details.)
- [BHNSS19] Bonnetain, X., Hosoyamada, A., Naya-Plasencia, M., Sasaki, Y., Schrottenloher, A.: Quantum Attacks without Superposition Queries: the Offline Simon’s Algorithm. (ASIACRYPT 2019) [Proceeding ver. (Springer LNCS)] [Full ver. (IACR ePrint / arXiv)] See also [BHNSS20].
- [HSTX19] Hosoyamada, A., Sasaki, Yu., Xagawa, K.: Improved Quantum Multicollision-Finding Algorithm. (PQCrypto 2019) [Proceeding ver. (Springer LNCS)] [Full ver. (IACR ePrint / arXiv)]
- [IHMSI19] Gembu, I., Hosoyamada, A., Matsumoto, R., Sasaki, M., Iwata, T.: Quantum Chosen-Ciphertext Attacks Against Feistel Ciphers. (CT-RSA 2019) [Proceeding ver. (Springer LNCS)] [Full ver. (IACR ePrint)]
- [HY18] Hosoyamada, A., Yasuda, K.: Building Quantum-One-Way Functions from Block Ciphers: Davies-Meyer and Merkle-Damgård Constructions. (ASIACRYPT 2018) [Proceeding ver. (SpringerLNCS)] [Full ver. (IACR ePrint)]
- [HS18a] Hosoyamada, A., Sasaki, Y.: Quantum Demiric-Selçuk Meet-in-the-Middle Attacks: Applications to 6-Round Generic Feistel Constructions. (SCN 2018) [Proceeding ver. (Springer LNCS)] [Full ver. (IACR ePrint)]
- [HS18b] Hosoyamada, A., Sasaki, Y.: Cryptanalysis Against Symmetric-Key Schemes with Online Classical Queries and Offline Quantum Computations. (CT-RSA 2018) [Proceeding ver. (Springer LNCS)] [Full ver. (IACR ePrint)]
- [HSX17] Hosoyamada, A., Sasaki, Yu., Xagawa, K.: Quantum Multicollision-Finding Algorithm. (ASIACRYPT 2017) [Proceeding ver. (Springer LNCS)] [Full ver. (IACR ePrint)]
- [HA17] Hosoyamada, A., Kazumaro, A.; On Quantum Related-Key Attacks on Iterated Even-Mansour Ciphers. (IWSEC 2017) (Best Paper Award) [Proceeding ver. (Springer LNCS)] See also [HA19].
Peer-Reviewed International Conference (without proceedings)
- [BHNSS20] Bonnetain, X., Hosoyamada, A., Naya-Plasencia, M., Sasaki, Y., Schrottenloher, A.: Quantum Attacks without Superposition Queries: the Offline Simon’s Algorithm. (QIP 2020, single-session talk) See also [BHNSS19].
Journals
- [HSTX20] Hosoyamada, A., Sasaki, Y., Tani, S., Xagawa, K.: Quantum algorithm for the multicollision problem. To appear on Theoretical Computer Science. [Link] (Note: Preliminary versions of this paper appeared at ASIACRYPT 2017 [HSX17] and PQCrypto 2019 [HSTX20].)
- [HA19] Hosoyamada, A., Aoki, K.: On Quantum Related-Key Attacks on Iterated Even-Mansour Ciphers. IEICE Transactions 102-A(1), 27-34 (2019) [Link] (Note: A preliminary version of this paper appeared at IWSEC 2017 [HA17].)
Preprints
- [HNS20] Hosoyamada, A., Naya-Plasencia, M., Sasaki, Y.: Improved Attacks on sLiSCP Permutation and Tight Bound of Limited Birthday Distinguishers IACR Cryptology ePrint Archive 2020/1089 (2020) [Link]
- [CHLS20] Cid, C., Hosoyamada, A., Liu, Y., Sim, S.: Quantum Cryptanalysis on Contracting Feistel Structures and Observation on Related-key settings. IACR Cryptology ePrint Archive 2020/959 (2020) [Link] (Note: This paper’s results are obtained in a discussion group of ASK 2019.)
Other Activities
Invited Seminar
2019.10
Dagstuhl Seminar 19421, Quantum Cryptanalysis, October 13 – 18, 2019, Schloss Dagstuhl, Wadern, Germany [Link]
Invited Talk (International)
2019.11
The 9th Asian-workshop on symmetric key cryptography, December 13 – 15, 2019, University of Hyogo, Kobe, Japan [Link]
Reports
2020.1
[H20] Hosoyamada, A.: Review and Evaluation of the Effect of Quantum Computers on the Security of Symmetric-Key Cryptographic Schemes. CRYPTREC Investigation Reports on Cryptographic Techniques in FY 2019. [Link] (in Japanese)
Awards
2020.12 (planned)
Asiacrypt 2020 Best Paper Award.
2019.01
SCIS 2018 Paper Award.
2017.08
IWSEC 2017 Best Paper Award.
Biography
Job Experience
2016.04 – present
Researcher, NTT Secure Platform Laboratories, NTT Corporation.
Education
2018.10 – present
Doctoral course student in the Department of Information and Communication Engineering, Nagoya University.
2014.04 – 2016.03
M. Sc. from Kyoto University. (Major: Algebraic/Differential Topology)
2010.04 – 2014.03
B. Sc. from Kyoto University. (Major: Mathematics)
