IRONHIDE: A Secure Multicore that Efficiently Mitigates Microarchitecture State Attacks for Interactive Applications
It addresses performance degradation in secure computing for interactive applications, offering a novel hardware solution to mitigate microarchitecture state attacks with significant speedups.
The paper tackles the performance overhead of microarchitecture state purging in secure processors for interactive applications by proposing IRONHIDE, a multicore design with spatially isolated secure and insecure clusters, resulting in a 2.1x performance improvement over MI6 and 20% over SGX-like baselines.
Microprocessors enable aggressive hardware virtualization by means of which multiple processes temporally execute on the system. These security-critical and ordinary processes interact with each other to assure application progress. However, temporal sharing of hardware resources exposes the processor to various microarchitecture state attacks. State-of-the-art secure processors, such as MI6 adopt Intel's SGX enclave execution model. MI6 architects strong isolation by statically isolating shared memory state, and purging the microarchitecture state of private core, cache, and TLB resources on every enclave entry and exit. The purging overhead significantly impacts performance as the interactivity across the secure and insecure processes increases. This paper proposes IRONHIDE that implements strong isolation in the context of multicores to form spatially isolated secure and insecure clusters of cores. For an interactive application comprising of secure and insecure processes, IRONHIDE pins the secure process(es) to the secure cluster, where they execute and interact with the insecure process(es) without incurring the microarchitecture state purging overheads on every interaction event. IRONHIDE improves performance by 2.1x over the MI6 baseline for a set of user and OS interactive applications. Moreover, IRONHIDE improves performance by 20% over an SGX-like baseline, while also ensuring strong isolation guarantees against microarchitecture state attacks.