Program execution control method, for use in ensuring security programs execute in their intended sequence, by using a digital signature for each operator in each command execution step

摘要

Method for controlling the execution of a program implementing successive instructions each comprising at least the execution of an operator (OPEj). During the execution of each instruction: a digital signature (SIGN) is determined for each operator taking into account at least a part of an operator digital identification code and at least partially a digital code identifying the position of the operator within the program, without taking into account the values of the instruction operands; and comparison of the calculated signature with an expected value stored in memory. The invention also relates to a corresponding processor for program execution.