Departmental Papers (CIS)

Date of this Version

June 2003

Document Type

Conference Paper


Copyright 2003 IEEE. Reprinted from Proceedings of the 16th IEEE Computer Security Foundations Workshop (CSFW 2003) pages 29-43.
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Noninterference is a property of sequential programs that is useful for expressing security policies for data confidentiality and integrity. However, extending noninterference to concurrent programs has proved problematic. In this paper we present a relatively expressive secure concurrent language. This language, based on existing concurrent calculi, provides first-class channels, higher-order functions, and an unbounded number of threads. Well-typed programs obey a generalization of noninterference that ensures immunity to internal timing attacks and to attacks that exploit information about the thread scheduler. Elimination of these refinement attacks is possible because the enforced security property extends noninterference with observational determinism. Although the security property is strong, it also avoids some of the restrictiveness imposed on previous security-typed concurrent languages.



Date Posted: 21 November 2004

This document has been peer reviewed.