Correct Audit Logging in Concurrent Systems

Audit logging provides post-facto analysis of runtime behavior for different purposes, including error detection, amelioration of system operations, and the establishment of security in depth. This necessitates some level of assurance on the quality of the generated audit logs, i.e., how well the audit log represents the events transpired during the execution. Information-algebraic techniques have been proposed to formally specify this relation and provide a framework to study correct audit log generation in a provable fashion. However, previous work fall short on how to guarantee this property of audit logging in concurrent environments. In this paper, we study an implementation model in a concurrent environment. We propose an algorithm that instruments a concurrent system according to a formal specification of audit logging requirements, so that any instrumented concurrent system guarantees correct audit log generation. As an application, we consider systems with microservices architecture, where logging an event by a microservice is conditioned on the occurrence of a collection of events that take place in other microservices of the system.