One software tool for testing square s-boxes

An encryption technique is widely used to keep data confidential. Most of the block symmetric algorithms use substitution functions. Often this functions use so called S-BOX matrix. In this paper author presents one software tool for testing and measuring square s-boxes. Based of information theory functions for testing static and dynamic criteria are presented. These criteria are mathematically defined for square s-boxes. Two new criteria "private criteria" a proposed and pseudo codes for they creation and testing are presented.