Paper 2018/126
Onion-AE: Foundations of Nested Encryption
Phillip Rogaway and Yusi Zhang
Abstract
Nested symmetric encryption is a well-known technique for low-latency communication privacy. But just what problem does this technique aim to solve? In answer, we provide a provable-security treatment for onion authenticated-encryption (onion-AE). Extending the conventional notion for authenticated-encryption, we demand indistinguishability from random bits and time-of-exit authenticity verification. We show that the encryption technique presently used in Tor does not satisfy our definition of onion-AE security, but that a construction by Mathewson (2012), based on a strong, tweakable, wideblock PRP, does do the job. We go on to discuss three extensions of onion-AE, giving defini- tions to handle inbound flows, immediate detection of authenticity errors, and corrupt ORs.
Metadata
- Available format(s)
-
PDF
- Category
- Foundations
- Publication info
- Published elsewhere. PETS 2018, Issue 2
- Keywords
- Anonymityauthenticated encryptiononion routingprivacyoracle silencingprovable securityTor
- Contact author(s)
- ysizhang @ ucdavis edu
- History
- 2018-02-05: received
- Short URL
- https://ia.cr/2018/126
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2018/126,
author = {Phillip Rogaway and Yusi Zhang},
title = {Onion-{AE}: Foundations of Nested Encryption},
howpublished = {Cryptology {ePrint} Archive, Paper 2018/126},
year = {2018},
url = {https://eprint.iacr.org/2018/126}
}
