DriverGuard: Virtualization-Based Fine-Grained Protection on I/O Flows

Most commodity peripheral devices and their drivers are geared to achieve high performance with security functions being opted out. The absence of strong security measures invites attacks on the I/O data and consequently posts threats to those services feeding on them, such as fingerprint-based biometric authentication. In this article, we present a generic solution called DriverGuard, which dynamically protects the secrecy of I/O flows such that the I/O data are not exposed to the malicious kernel. Our design leverages a composite of cryptographic and virtualization techniques to achieve fine-grained protection without using any extra devices and modifications on user applications. We implement the DriverGuard prototype on Xen by adding around 1.7K SLOC. DriverGuard is lightweight as it only needs to protect around 2% of the driver code’s execution. We measure the performance and evaluate the security of DriverGuard with three input devices (keyboard, fingerprint reader and camera) and three output devices (printer, graphic card, and sound card). The experiment results show that DriverGuard induces negligible overhead to the applications.