Zi-Yuan Liu

I’m currently pursuing my second Ph.D. degree at Graduate school of Natural Science & Technology, Kanazawa University, Japan (advised by Prof. Masahiro Mambo). Previously, I obtained my Ph.D. degree and M.S.Eng. degree in Computer Science at National Chengchi University, Taiwan under the supervision of Prof. Raylin Tso and my B.Eng. degree in Computer Science at National Tsing Hua University, Taiwan.

My primary research focus lies in the field of applied cryptography, with particular emphasis on areas such as searchable encryption and identity-based encryption. Furthermore, I also focus on lattice-based cryptosystems, which are likely to be the critical cryptography of the next century due to their resistance to quantum computer attacks.

selected publications

DCC
Predicate encryption with selective-opening security for receivers: formal definition, generic construction, and concrete instantiations for several primitives

Yi-Fan Tseng, Zi-Yuan Liu, and Raylin Tso

Des. Codes Cryptogr., 1–24, 2024

Early Access

Abs Bib HTML

With the rise of cloud computing, multi-user scenarios have become a common setting for data sharing nowadays. The conservative security notion might not be sufficient for such a data sharing model. As a response to this challenge, there has been significant research targeting security against receiver selective-opening (RSO) attacks. However, we found that none of these studies discuss RSO security specifically for predicate encryption (PE)—an encryption mechanism naturally designed for multi-user data sharing. This manuscript first formalizes the RSO security for PE. We then present a generic PE construction that achieves RSO security based on the simulation-based definition. Our work also features several instantiations for various predicate families, including attribute-based encryption for the monotone span program, which is known as one of the most expressive PE.
@article{DBLP:journals/dcc/TLT24, author = {Tseng, Yi-Fan and Liu, Zi-Yuan and Tso, Raylin}, title = {Predicate encryption with selective-opening security for receivers: formal definition, generic construction, and concrete instantiations for several primitives}, journal = {Des. Codes Cryptogr.}, year = {2024}, pages = {1--24}, note = {Early Access}, }

AsiaCCS

Public-key Authenticated Encryption with Keyword Search: Cryptanalysis, Enhanced Security, and Quantum-resistant Instantiation

Zi-Yuan Liu, Yi-Fan Tseng, Raylin Tso, Masahiro Mambo, and Yu-Chi Chen

In ASIA CCS ’22: ACM Asia Conference on Computer and Communications Security, Nagasaki, Japan, 30 May 2022 - 3 June 2022 , 423–436, 2022

Bib HTML Acceptance Rate: 18.3% (85/463)

@inproceedings{DBLP:conf/asiaccs/LiuTTMC22,
  author = {Liu, Zi{-}Yuan and Tseng, Yi{-}Fan and Tso, Raylin and Mambo, Masahiro and Chen, Yu{-}Chi},
  editor = {Suga, Yuji and Sakurai, Kouichi and Ding, Xuhua and Sako, Kazue},
  title = {Public-key Authenticated Encryption with Keyword Search: Cryptanalysis,
                    Enhanced Security, and Quantum-resistant Instantiation},
  booktitle = {{ASIA} {CCS} '22: {ACM} Asia Conference on Computer and Communications
                    Security, Nagasaki, Japan, 30 May 2022 - 3 June 2022},
  pages = {423--436},
  publisher = {{ACM}},
  year = {2022},
}