Protection of software against unauthorized use, reproduction or alteration, e.g. for protection of chip card software or software protected by a material key associated with a USB port using a principle of a verification variable

摘要

Method for creation of protected software wherein: a variable is selected in the vulnerable software code that is to be protected and protected software code is generated by modifying the vulnerable code such that the selected variable resides in the memory of the executing data processing unit. The invention also relates to a corresponding system, data processing unit and assembly for distribution of protected software.