Biblio

Language-based information-flow control (IFC) techniques often rely on special purpose, ad-hoc primitives to address different covert channels that originate in the runtime system, beyond the scope of language constructs. Since these piecemeal solutions may not compose securely, there is a need for a unified mechanism to control covert channels. As a first step towards this goal, we argue for the design of a general interface that allows programs to safely interact with the runtime system and the available computing resources. To coordinate the communication between programs and the runtime system, we propose the use of asynchronous exceptions (interrupts), which, to the best of our knowledge, have not been considered before in the context of IFC languages. Since asynchronous exceptions can be raised at any point during execution-often due to the occurrence of an external event-threads must temporarily mask them out when manipulating locks and shared data structures to avoid deadlocks and, therefore, breaking program invariants. Crucially, the naive combination of asynchronous exceptions with existing features of IFC languages (e.g., concurrency and synchronization variables) may open up new possibilities of information leakage. In this paper, we present MACasync, a concurrent, statically enforced IFC language that, as a novelty, features asynchronous exceptions. We show how asynchronous exceptions easily enable (out of the box) useful programming patterns like speculative execution and some degree of resource management. We prove that programs in MACasync satisfy progress-sensitive non-interference and mechanize our formal claims in the Agda proof assistant.

Modern multicore System-on-Chips (SoCs) are regularly designed with third-party Intellectual Properties (IPs) and software tools to manage the complexity and development cost. This approach naturally introduces major security concerns, especially for those SoCs used in critical applications and cyberinfrastructure. Despite approaches like split manufacturing, security testing and hardware metering, this remains an open and challenging problem. In this work, we propose a dynamic intrusion detection approach to address the security challenge. The proposed runtime system (SoCINT) systematically gathers information about untrusted IPs and strictly enforces the access policies. SoCINT surpasses the-state-of-the-art monitoring systems by supporting hardware tracing, for more robust analysis, together with providing smart counterintelligence strategies. SoCINT is implemented in an open source processor running on a commercial FPGA platform. The evaluation results validate our claims by demonstrating resilience against attacks exploiting erroneous or malicious IPs.