A General Dynamic Information Flow Tracking Framework for Security Applications

Many software security solutions require accurate tracking of control/data dependencies among information objects in network applications. This paper presents a general dynamic information flow tracking framework (called GIFT) for C programs that allows an application developer to associate application-specific tags with input data, instruments the application to propagate these tags to all the other data that are control/data-dependent on them, and invokes application-specific processing on output data according to their tag values. To use GIFT, an application developer only needs to implement input and output proxy functions to tag input data and to perform tag-dependent processing on output data, respectively. To demonstrate the usefulness of GIFT, we implement a complete GIFT application called Aussum, which allows selective sandboxing of network client applications based on whether their inputs are "tainted" or not. For a set of computation-intensive test applications, the measured elapsed time overhead of GIFT is less than 35%