An iterative method for secure inter-procedural information flow control

Abstract

An information flow control policy specifies the manner in which classified information flows from one object to another. A link-time algorithm is presented for an information flow certification mechanism designed for modular programming systems. The mechanism combines a compile-time algorithm developed for object-oriented systems with the link-time algorithm described. The compile-time algorithm partially verifies the security of each procedure independently and generates equations which express potential flows caused by parameter passing. The link-time algorithm completes the certification of the entire program by verifying the interprocedural information flows. It analyzes the equations for all procedures in the program and calculates the least fixed point by using a standard iterative method.<>