Securing IoT Protocol Implementations Through Hardware Monitoring

The Internet of Things (IoT) represents the technical foundation to solve some of the most important societal and environmental problems. One of the key challenges in IoT systems is providing security for distributed, networked IoT components that are implemented with potentially very low-end embedded processing systems. As the value of sensor data and actuator access increases in IoT deployments, attackers may increasingly target these vulnerable systems and protocol implementations running on them. For protocols that involve economic transactions on blockchains, as we show in our work, there is a direct monetary value associated with successful attacks. To address this problem, we present a hardware monitoring system that augments processors with logic that tracks the correct execution of software on the embedded systems. Attacks on the system, such as buffer overflow attacks, are recognized and stopped by the hardware monitor. Therefore, the system can avoid economic loss due to an attack and ensure that the protocol implementation is secured. We show the effectiveness of our system on a prototype that uses Linux running on a soft-core LEON3 processor on an Intel Stratix IV FPGA and interacts with the Ethereum blockchain.