Terminator : A Secure Coprocessor to Accelerate Real-Time AntiViruses Using Inspection Breakpoints

Abstract

AntiViruses (AVs) are essential to face the myriad of malware threatening Internet users. AVs operate in two modes: on-demand checks and real-time verification. Software-based real-time AVs intercept system and function calls to execute AV’s inspection routines, resulting in significant performance penalties as the monitoring code runs among the suspicious code. Simultaneously, dark silicon problems push the industry to add more specialized accelerators inside the processor to mitigate these integration problems. In this article, we propose Terminator , an AV-specific coprocessor to assist software AVs by outsourcing their matching procedures to the hardware, thus saving CPU cycles and mitigating performance degradation. We designed Terminator   to be flexible and compatible with existing AVs by using YARA and ClamAV rules. Our experiments show that our approach can save up to 70 million CPU cycles per rule when outsourcing on-demand checks for matching typical, unmodified YARA rules against a dataset of 30 thousand in-the-wild malware samples. Our proposal eliminates the AV’s need for blocking the CPU to perform full system checks, which can now occur in parallel. We also designed a new inspection breakpoint mechanism that signals to the coprocessor the beginning of a monitored region, allowing it to scan the regions in parallel with their execution. Overall, our mechanism mitigated up to 44% of the overhead imposed to execute and monitor the SPEC benchmark applications in the most challenging scenario.