Side-Channel Analysis of Block Ciphers using CERG-GMU Interface on SASEBO-GII

Abstract

Field Programmable Gate Array(FPGAs) are used as a common platform for almost any type of design due to an increase in their logic capacity and various features such as DSP blocks, embedded processors, etc. A cryptographic algorithm implemented on FPGAs leaks data sensitive information through side channels such as power consumption, time taken for computations, temperature, etc. Many side-channel cryptanalysis methods exist to attack the physical implementation of cryptographic algorithms, thus rendering the algorithms insecure. One branch of side-channel attack is Di erential Power Analysis (DPA); where the attack is based on information gained from the power consumption of the cryptosystem. Recently, the Research Center for Information (RCIS) of AIST and Tohoku University developed the Side Channel Attack Standard Evaluation Board (SASEBO) as a common platform for evaluating side channel attacks. There are two FPGAs on a SASEBO board, a cryptographic FPGA - where the algorithm is implemented and a control FPGA - which communicates the data between the software (SASEBO Waveform Acquisition) and the cryptographic FPGA in an e cient manner. Sasebo Waveform Acquisition interacts with the hardware for processing data and collecting power traces for a DPA attack. The current interface between the control and cryptographic FPGA on the SASEBO-GII board is used to implement a block cipher and a hash algorithm. However, as the standard hardware interface proposed by the Cryptographic Engineering Research Group (CERG) of George Mason University has a di erent protocol for block ciphers and hash functions, the algorithms could not be directly integrated with the SASEBO-GII interface. This thesis focuses on designing a new interface, with modi cations made to the original SASEBO waveform acquisition software and the hardware on the control FPGA to interact with the protocol of CERG-GMU. The data communication between the software and hardware with implementations of lightweight block cipher was tested successfully on the modi ed 8-bit interface. Also, results from the DPA attack on AES on both the original SASEBO-GII interface and the modi ed interface are discussed.