Security-typed programming languages aim to track insecure information flows in application program. This is achieved by extending data types with security labels in order to identify the confidentiality and integrity policies for each data element. Such policies specify which principals or entities are allowed to read from or write to the value of data respectively. In this paper, we evaluate the run-time overhead of dynamic information flow (DIF) analysis in security typed programming languages. Such analysis is performed by including the security labeling in the dynamic operational semantics. Our evaluation mechanism relies on developing two different language implementations for a simple while programming language that has been considered as a case of study. The first one is a traditional interpreter that implements the ordinary operational semantics of the language without security labeling of data types and hence performs no information flow analysis. The second one is an interpreter that performs a dynamic information flow analysis by implementing the security labeling semantics (where language data types are augmented with security labels). Next, two execution times of a program executed using both interpreters are measured (i.e., one execution time for each interpreter). The resulting difference in execution time represents the absolute run-time overhead of dynamic information flow analysis. We have calculated the difference in execution time for some benchmark programs that are executed using both implementations.

Dynamic information flow; security labeling; run-time overhead; operational semantics

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