Masked FPGA Bitstream Encryption via Partial Reconfiguration

Abstract

Field Programmable Gate Arrays (FPGA), as one of the popular circuit implementation platforms, provide the flexible and powerful way for different applications. IC designs are configured to FPGA through bitstream files. However, the configuration process can be hacked by side channel attacks (SCA) to acquire the critical design information, even under the protection of encryptions. Reports have shown many successful attacks against the FPGA cryptographic systems during the bitstream loading process to acquire the entire design. Current countermeasures, mostly random masking methods, are effective but also introduce large hardware complexity. They are not suitable for resource-constrained scenarios such as Internet of Things (IoT) applications. In this paper, we propose a new secure FPGA masking scheme to counter the SCA. By utilizing the FPGA partial reconfiguration feature, the proposed technique provides a light-weight and flexible solution for the FPGA decryption masking.