Paper 2025/1213 Original: eprint.iacr.org/2025/1213 ↗

Tightly Secure Public-Key Encryption with Equality Test Supporting Flexible Authorization in the Standard Model

Yi-Fan Tseng
Yi-Jiin Lu
Tien-Lin Tsai
Zi-Yuan Liu
Abstract

We introduce a novel Public Key Encryption with Equality Test supporting Flexible Authorization scheme offering User-Level, Ciphertext-Level, and User-Specific-Ciphertext-Level authorizations. Notably, our construction achieves security under the Decisional Diffie-Hellman assumption with a tight reduction, whereas the existing works are either not tightly secure or rely heavily on the random oracles. By relying solely on the standard DDH assumption, our scheme offers practical implementation without specialized cryptographic structures.

Metadata
Available format(s)
PDF
Category
Public-key cryptography
Publication info
Preprint.
History
2025-06-30: last updated
2025-06-30: published
Short URL
https://ia.cr/2025/1213
License
https://creativecommons.org/licenses/by-nc-sa/4.0/

BibTeX

@misc{cryptoeprint:2025/1213,
      author = {Yi-Fan Tseng and Yi-Jiin Lu and Tien-Lin Tsai and Zi-Yuan Liu},
      title = {Tightly Secure Public-Key Encryption with Equality Test Supporting Flexible Authorization in the Standard Model},
      howpublished = {Cryptology {ePrint} Archive, Paper 2025/1213},
      year = {2025},
      url = {https://eprint.iacr.org/2025/1213}
}
Note: In order to protect the privacy of readers, this archive does not use cookies or embedded third party content.