COUNTERMEASURE METHOD IN AN ELECTRONIC COMPONENT USING A SECRET KEY CRYPTOGRAPHIC ALGORITHM

摘要

In an electronic component using a secret key K cryptographic algorithm, the algorithm operation comprises the use of first means TC0 for supplying output data S from an input data E, the output data and/or derived data being manipulated by critical instructions, a countermeasure method consists in using other means TC1, TC2 such that the output data and the derived data are unpredictable, said other means being obtained from said first means by an or else operation with a random value u or a derived random value e(p(u) on one and/or the other of the input and output data of said first means TC0.