A Formal Analysis of Timing Channel Security via Bucketing

Tachio Terauchi, Timos Antonopoulos

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

This paper investigates the effect of bucketing in security against timing channel attacks. Bucketing is a technique proposed to mitigate timing-channel attacks by restricting a system’s outputs to only occur at designated time intervals, and has the effect of reducing the possible timing-channel observations to a small number of possibilities. However, there is little formal analysis on when and to what degree bucketing is effective against timing-channel attacks. In this paper, we show that bucketing is in general insufficient to ensure security. Then, we present two conditions that can be used to ensure security of systems against adaptive timing channel attacks. The first is a general condition that ensures that the security of a system decreases only by a limited degree by allowing timing-channel observations, whereas the second condition ensures that the system would satisfy the first condition when bucketing is applied and hence becomes secure against timing-channel attacks. A main benefit of the conditions is that they allow separation of concerns whereby the security of the regular channel can be proven independently of concerns of side-channel information leakage, and certain conditions are placed on the side channel to guarantee the security of the whole system. Further, we show that the bucketing technique can be applied compositionally in conjunction with the constant-time-implementation technique to increase their applicability. While we instantiate our contributions to timing channel and bucketing, many of the results are actually quite general and are applicable to any side channels and techniques that reduce the number of possible observations on the channel.

Original languageEnglish
Title of host publicationPrinciples of Security and Trust - 8th International Conference, POST 2019, Held as Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2019, Proceedings
EditorsFlemming Nielson, David Sands
PublisherSpringer-Verlag
Pages29-50
Number of pages22
ISBN (Print)9783030171377
DOIs
Publication statusPublished - 2019 Jan 1
Event8th International Conference on Principles of Security and Trust, POST 2019 Held as Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2019 - Prague, Czech Republic
Duration: 2019 Apr 62019 Apr 11

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume11426 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349

Conference

Conference8th International Conference on Principles of Security and Trust, POST 2019 Held as Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2019
CountryCzech Republic
CityPrague
Period19/4/619/4/11

    Fingerprint

ASJC Scopus subject areas

  • Theoretical Computer Science
  • Computer Science(all)

Cite this

Terauchi, T., & Antonopoulos, T. (2019). A Formal Analysis of Timing Channel Security via Bucketing. In F. Nielson, & D. Sands (Eds.), Principles of Security and Trust - 8th International Conference, POST 2019, Held as Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2019, Proceedings (pp. 29-50). (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics); Vol. 11426 LNCS). Springer-Verlag. https://doi.org/10.1007/978-3-030-17138-4_2