METHOD FOR CREATING A SECURE COUNTER ON AN ON-BOARD COMPUTER SYSTEM COMPRISING A CHIP CARD

摘要

According to the inventive method, the chip card, a counting function (FC), a counter (Cpt) and a private key (Cf) stored in the write-only part of the memory region are stored in a persistant memory, the counter and the private key (Cf) being accessible only by the counting function (FC). When the chip card receives a counter request emitted by an requesting entity (ER), the counting function (FC) performs a modification of the counter (Cpt) and a calculation of a signature, and sends a response to the applicant entity (ER). When the on-board system receives the response to the counter request, the signature contained in the response is checked.