SIMON 32/64 and 64/128 block cipher: Study of cross correlation and linear span attack immunity

Power and computing limitations hinder the ability of many devices to support stringent security protocols. Smart sensors, RFID tags, and wearable devices are typical examples of such devices. Lightweight cryptography is concerned with the design and implementation of cryptography algorithms in environments with limited computing and power resources. This paper presents a realization of a hardware efficient lightweight cryptography block cipher SIMON in C/C++ (SIMON 32/64 and 64/128). Analysis is performed in order to investigate its input/output cross correlation and among output sets. The proposed block cipher's immunity to linear span attacks is also investigated using the Berlekamp-Massy algorithm. It is concluded that the proposed block cipher is not immune to linear span attacks, as the analysis has shown a linear span for certain components to be less than N/2, with a profile of probability of 1/3 in 1 million iterations.