Using Equivalence Relations for Corrective Enforcement of Security Policies

In this paper, we present a new framework of runtime security policy enforcement Building on previous studies, we examine the enforcement power of monitors able to transform their target's execution, rather than simply accepting it if it is valid, or aborting it otherwise We bound this ability by a restriction stating that any transformation must preserve equivalence between the monitor's input and output We proceed by giving examples of meaningful equivalence relations and identify the security policies that are enforceable with their use We also relate our work to previous findings in this field Finally, we investigate how an a priori knowledge of the target program's behavior would increase the monitor's enforcement power