Biblio

Failing to properly isolate components in the same address space has resulted in a substantial amount of vulnerabilities. Enforcing the least privilege principle for memory accesses can selectively isolate software components to restrict attack surface and prevent unintended cross-component memory corruption. However, the boundaries and interactions between software components are hard to reason about and existing approaches have failed to stop attackers from exploiting vulnerabilities caused by poor isolation. We present the secure memory views (SMV) model: a practical and efficient model for secure and selective memory isolation in monolithic multithreaded applications. SMV is a third generation privilege separation technique that offers explicit access control of memory and allows concurrent threads within the same process to partially share or fully isolate their memory space in a controlled and parallel manner following application requirements. An evaluation of our prototype in the Linux kernel (TCB textless 1,800 LOC) shows negligible runtime performance overhead in real-world applications including Cherokee web server (textless 0.69%), Apache httpd web server (textless 0.93%), and Mozilla Firefox web browser (textless 1.89%) with at most 12 LOC changes.

With the advent of the Internet of Things (IoT), billions of devices are expected to continuously collect and process sensitive data (e.g., location, personal health). Due to limited computational capacity available on IoT devices, the current de facto model for building IoT applications is to send the gathered data to the cloud for computation. While private cloud infrastructures for handling large amounts of data streams are expensive to build, using low cost public (untrusted) cloud infrastructures for processing continuous queries including on sensitive data leads to concerns over data confidentiality. This paper presents STYX, a novel programming abstraction and managed runtime system, that ensures confidentiality of IoT applications whilst leveraging the public cloud for continuous query processing. The key idea is to intelligently utilize partially homomorphic encryption to perform as many computationally intensive operations as possible in the untrusted cloud. STYX provides a simple abstraction to the IoT developer to hide the complexities of (1) applying complex cryptographic primitives, (2) reasoning about performance of such primitives, (3) deciding which computations can be executed in an untrusted tier, and (4) optimizing cloud resource usage. An empirical evaluation with benchmarks and case studies shows the feasibility of our approach.