An Efficient Lightweight Cryptographic Instructions Set Extension for IoT Device Security

The Internet of Things is changing all sectors such as manufacturing, agriculture, city infrastructure, and the automotive industry. All these applications ask for secure processors that can be embedded in the IoT devices. Furthermore, these devices are restricted in terms of computing capabilities, memory, and power consumption. A major challenge is how to meet the need for security in such resource-constrained devices. This paper presents a customized version of LEON3, the ReonV RISCV (Reduced Instruction Set Computer-five) processor, dedicated for IoT applications that has strong effective security mechanisms built in at the design stage. Firstly, efficient lightweight cipher designs are elaborated and validated. Then, the proposed cryptographic instructions (PRESENT and PRINCE) are integrated into the default instruction set architecture of the ReonV processor core. The instruction set extensions (ISE) of lightweight cipher modules can be instantiated in software routines exactly as the instructions of the base architecture. A single instruction is needed to implement a full lightweight cryptographic instruction. The customized ReonV RISCV processor is implemented on a Xilinx FPGA platform and is evaluated for Slice LUTs plus FF-pairs, frequency, and throughput. Obtained results show that our proposed concepts not only can achieve good encryption results with high performance and reduced cost but also are secure enough to resist against the most common attacks.