ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Cryptographic reverse firewalls for interactive proof systems

Ganesh, C and Magri, B and Venturi, D (2020) Cryptographic reverse firewalls for interactive proof systems. In: 47th International Colloquium on Automata, Languages, and Programming, ICALP 2020, 8-11, July 2020, Germany.

[img] PDF
lei_int_pro_inf_lip_168_2020.pdf - Published Version
Restricted to Registered users only

Download (545kB) | Request a copy
Official URL: https://dx.doi.org/10.4230/LIPIcs.ICALP.2020.55

Abstract

We study interactive proof systems (IPSes) in a strong adversarial setting where the machines of honest parties might be corrupted and under control of the adversary. Our aim is to answer the following, seemingly paradoxical, questions: Can Peggy convince Vic of the veracity of an NP statement, without leaking any information about the witness even in case Vic is malicious and Peggy does not trust her computer? Can we avoid that Peggy fools Vic into accepting false statements, even if Peggy is malicious and Vic does not trust her computer? At EUROCRYPT 2015, Mironov and Stephens-Davidowitz introduced cryptographic reverse firewalls (RFs) as an attractive approach to tackling such questions. Intuitively, a RF for Peggy/Vic is an external party that sits between Peggy/Vic and the outside world and whose scope is to sanitize Peggy's/Vic's incoming and outgoing messages in the face of subversion of her/his computer, e.g. in order to destroy subliminal channels. In this paper, we put forward several natural security properties for RFs in the concrete setting of IPSes. As our main contribution, we construct efficient RFs for different IPSes derived from a large class of Sigma protocols that we call malleable. A nice feature of our design is that it is completely transparent, in the sense that our RFs can be directly applied to already deployed IPSes, without the need to re-implement them.

Item Type: Conference Paper
Publication: Leibniz International Proceedings in Informatics, LIPIcs
Publisher: Schloss Dagstuhl- Leibniz-Zentrum fur Informatik GmbH, Dagstuhl Publishing
Additional Information: The copyright of this article belongs to Schloss Dagstuhl- Leibniz-Zentrum fur Informatik GmbH, Dagstuhl Publishing
Keywords: Automata theory; Cryptography; Robots; Trusted computing, Interactive proof system; Security properties; Sigma protocols; Subliminal channel, Computer system firewalls
Department/Centre: Division of Electrical Sciences > Computer Science & Automation
Date Deposited: 25 Aug 2020 10:37
Last Modified: 25 Aug 2020 10:37
URI: http://eprints.iisc.ac.in/id/eprint/66370

Actions (login required)

View Item View Item