METHOD FOR TESTING THE RESISTANCE OF A CIRCUIT TO AUXILIARY CHANNEL ANALYSIS

摘要

The invention relates to a test method comprising steps of acquiring a plurality of sets of values (Ci) each comprising values of a physical quantity or of logic signals, related to the activity of a circuit with test (CT) during the execution of distinct cryptographic operations (OPRK) applied to the same secret data (SD), counting, for each set of values, number of occurrences (HT) of the values of the set, computation a partial result (VL) of operation for each operation and each possible value (g) of a part of the secret data, calculation of accumulations (CH) of number of occurrences, each cumulation being obtained by adding the number of occurrences corresponding to operations that apply to the same possible value of the secret data portion, provide a partial operation result having the same value, and analyzing number of occurrence sums to determine the secret data portion you.