Control flow monitoring, information flow tracking and memory monitoring are the three main solutions to enhance the security of embedded system at the hardware architecture level. However, most of the current studies about the security of embedded system consider the above solutions in separate dimensions rather than a combined effort. We start from the operation model at the instruction level, and propose a security multi-strategy which combines information flow tracking and memory monitoring by studying the security operating mechanism of embedded system. As a hardware approach this strategy extends the embedded processor architecture with additional security defense control. The experimental results show this multi-strategy is more effective and can detect more malicious attacks than a single solution. The effectiveness of our proposed security multi-strategy has been verified in a Field programmable gate array (FPGA) prototype platform based on a customized Leon3 microprocessor.
