Effective blame for information-flow violations

Programs trusted with secure information should not release that information in ways contrary to system policy. However, when a program contains an illegal flow of information, current information-flow reporting techniques are inadequate for determining the cause of the error. Reasoning about information-flow errors can be difficult, as the flows involved can be quite subtle. We present a general model for information-flow blame that can explain the source of such security errors in code. This model is implemented by changing the information-flow verification procedure to: (1) generate supplementary information to reveal otherwise hidden program dependencies; (2) modify the constraint solver to construct a blame dependency graph; and (3) develop an explanation procedure that returns a complete and minimal error report. Our experiments show that information-flow errors can generally be explained and resolved by viewing only a small fraction of the total code.

• Type: Conference
• Year: 2008
• Where: SIGSOFT
• Authors: Dave King 0002, Trent Jaeger, Somesh Jha, Sanjit A. Seshia
• Keywords: Information-flow Errors, Information-flow Reporting Techniques, Information-flow Verification Procedure, SIGSOFT 2008, Software Engineering