High Performance Elliptic Curve GF(2m) Cryptoprocessor Secure Against Timing Attacks

This paper presents a high performance GF(2m) Elliptic Curve Cryptoprocessor architecture. The proposed cryptoprocessor is based on normal basis representation and uses three multipliers to perform parallel field multiplications. Point operations are performed using Mixed coordinate system to increase the performance and the immunity against timing attacks. The basic idea is to select a combination of point addition and point doubling from Mixed coordinate system such that both point operations requires the same number of multiplication cycles. Thus, an attacker cannot distinguish between point doubling and point addition and therefore it is not possible to extract the key pattern using a timing attack. Results show that the proposed cryptoprocessor gives better time complexity than existing designs which use fake computations by 76%. The proposed cryptoprocessor has been synthesized on a Xilinx Vertex II FPGA (xc2v8000) over GF(2173) and it required 159522 clock cycles to perform scalar multiplication. The proposed cryptoprocessor required 28154 Slices, which is only 60 % out of the total number of available Slices. Key words