Paper 2024/499
CCA Secure Updatable Encryption from Non-Mappable Group Actions
Abstract
Ciphertext-independent updatable encryption (UE) allows to rotate encryption keys and update ciphertexts via a token without the need to first download the ciphertexts. Although, syntactically, UE is a symmetric-key primitive, ciphertext-independent UE with forward secrecy and post-compromise security is known to imply public-key encryption (Alamati, Montgomery and Patranabis, CRYPTO 2019).
Constructing post-quantum secure UE turns out to be a difficult task. While lattices offer the necessary homomorphic properties, the introduced noise allows only a bounded number of updates. Group actions have become an important alternative, however, their structure is limited. The only known UE scheme by Leroux and Roméas (IACR ePrint 2022/739) uses effective triple orbital group actions which uses additional algebraic structure of CSIDH. Using an ideal cipher, similar to the group-based scheme
Metadata
- Available format(s)
-
PDF
- Category
- Cryptographic protocols
- Publication info
- Published elsewhere. PQCrypto 2024
- Keywords
- Updatable EncryptionGroup ActionsIsogeniesAlgebraic Group Action Model
- Contact author(s)
-
jonas meers @ rub de
driepel @ ucsd edu - History
- 2024-04-01: approved
- 2024-03-28: received
- See all versions
- Short URL
- https://ia.cr/2024/499
- License
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CC BY
BibTeX
@misc{cryptoeprint:2024/499, author = {Jonas Meers and Doreen Riepel}, title = {{CCA} Secure Updatable Encryption from Non-Mappable Group Actions}, howpublished = {Cryptology {ePrint} Archive, Paper 2024/499}, year = {2024}, url = {https://eprint.iacr.org/2024/499} }