Addressing covert termination and timing channels in concurrent information flow systems

Deian Stefan, Alejandro Russo, Pablo Buiras, Amit Levy, John C. Mitchell, David Mazières

Research output: Contribution to journalArticlepeer-review

28 Scopus citations


When termination of a program is observable by an adversary, confidential information may be leaked by terminating accordingly. While this termination covert channel has limited bandwidth for sequential programs, it is a more dangerous source of information leakage in concurrent settings. We address concurrent termination and timing channels by presenting a dynamic information-flow control system that mitigates and eliminates these channels while allowing termination and timing to depend on secret values. Intuitively, we leverage concurrency by placing such potentially sensitive actions in separate threads. While termination and timing of these threads may expose secret values, our system requires any thread observing these properties to raise its information-flow label accordingly, preventing leaks to lower-labeled contexts. We implement this approach in a Haskell library and demonstrate its applicability by building a web server that uses information-flow control to restrict untrusted web applications.

Original languageEnglish (US)
Pages (from-to)201-213
Number of pages13
JournalACM SIGPLAN Notices
Issue number9
StatePublished - Sep 2012
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • General Computer Science


  • Covert channels
  • Library
  • Monad


Dive into the research topics of 'Addressing covert termination and timing channels in concurrent information flow systems'. Together they form a unique fingerprint.

Cite this