Autocorrelation Coefficients of Two Classes of Semi-Bent Functions
Xuelian Li, Yupu Hu, Juntao Gao · 2011
Low autocorrelation is an important prerequisite of Boolean functions when used as combiners in stream ciphers. In this paper, we investigate the autocorrelation of two classes of semi-bent functions constructed by Charpin et al.. We give all the autocorrelation coefficients of these semi-bent functions and prove that they have not correlation immune. Our results show that, although these semi-bent functions have good nonlinearity, they have high autocorrelations. The cipher constructed by these semi-bent functions can be prone to differential-like cryptanalysis, and they can not resist correlation attacks. These potential weakness have to be considered before we deploy them in applications.