Addressing covert termination and timing channels in concurrent information flow systems
Journal article, 2012

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.

Monad

Covert channels

Library

Author

D. Stefan

Stanford University

Alejandro Russo

Chalmers, Computer Science and Engineering (Chalmers), Software Technology (Chalmers)

Pablo Buiras

Chalmers, Computer Science and Engineering (Chalmers), Software Technology (Chalmers)

Amit Levy

Stanford University

J. C. Mitchell

Stanford University

David Mazières

Stanford University

ACM SIGPLAN Notices

1523-2867 (ISSN)

Vol. 47 9 201-213

Subject Categories

Computer and Information Science

DOI

10.1145/2398856.2364557

More information

Latest update

3/6/2018 1