Provably Secure Online Authenticated Encryption and Bidirectional Online Channels

Arghya Bhattacharjee; Ritam Bhaumik; Daniel Collins; Mridul Nandi

Paper 2024/1346

Provably Secure Online Authenticated Encryption and Bidirectional Online Channels

Arghya Bhattacharjee

, Indian Statistical Institute, Technology Innovation Institute

Ritam Bhaumik

, École Polytechnique Fédérale de Lausanne, Technology Innovation Institute, Indian Statistical Institute

Daniel Collins

, École Polytechnique Fédérale de Lausanne, Purdue University West Lafayette

Mridul Nandi

, Indian Statistical Institute

Abstract

In this work, we examine online authenticated encryption with variable expansion. We follow a notion where both encryption and decryption are online, and security is ensured in the RUP (Release of Unverified Plaintext) setting. Then we propose a generic way of obtaining an online authenticated encryption mode from a tweakable online encryption mode based on the encode-then-encipher paradigm (Bellare and Rogaway, Asiacrypt 2000). To instantiate our generic scheme, we start with proposing a provably-secure tweakable online encryption mode called t-OleF, a tweakable version of OleF (Bhaumik and Nandi, ToSC 2016(2)), and then plug it into our generic scheme to obtain OlÆF, a provably-secure online authenticated encryption mode. As an application, we propose a primitive we call a bidirectional online channel suited for communication between lightweight devices.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Published elsewhere. Minor revision. SAC 2024
Keywords: online authenticated encryption tweakable online cipher bidirectional online channel OleF t-OleF OlÆF INT-RUP
Contact author(s): bhattacharjeearghya29 @ gmail com
bhaumik ritam @ gmail com
colli594 @ purdue edu
mridul nandi @ gmail com
History: 2024-08-30: revised; 2024-08-28: received; See all versions
Short URL: https://ia.cr/2024/1346
License: CC BY-NC-SA

BibTeX

@misc{cryptoeprint:2024/1346,
      author = {Arghya Bhattacharjee and Ritam Bhaumik and Daniel Collins and Mridul Nandi},
      title = {Provably Secure Online Authenticated Encryption and Bidirectional Online Channels},
      howpublished = {Cryptology {ePrint} Archive, Paper 2024/1346},
      year = {2024},
      url = {https://eprint.iacr.org/2024/1346}
}