Secured method for controlling the opening of lock devices from messages implementing a symmetrical encryption

摘要

A management site (10) generates an encrypted message by a public-key symmetrical encryption algorithm, the algorithm and the key being selected by the management site among a memorized list. The message (DKE), which includes an identifier of the encryption algorithm and key used, is transmitted to a portable device (16), which stores it. For the use, the message is transmitted to a secured module (20) that decrypts it, checks its compliance with an internal reference, and generates a digital accreditation controlling the unlocking of a lock device (18). The decryption is operated with the algorithm and the key recognized based on the identifiers of the message, selected among a list memorized by the secured module.

主权项

1. A method in secured module comprising a lock device, the method comprising:
during an initialization operation of the secure module, storing plural encryption algorithms and plural encryption keys in a memory of the secure module but not in a portable device; during a lock management operation:
wirelessly receiving from the portable device a message comprising digital data encrypted at a management site by a management site-selected one of the plural encryption algorithms and with a management site-selected one of the plural encryption keys, the message comprising:
(1) an indicator of an encryption method which refers to the management site-selected one of the plural encryption algorithms;(2) an encryption key which is the management site-selected one of the plural encryption keys; and(3) the encrypted digital data;using the indicator to select among the plural encryption algorithms a selected encryption algorithm which is the management site-selected one of the plural encryption algorithms;applying the encryption key to the selected encryption algorithm to perform a decryption of the encrypted digital data so that the decryption is performed at the secure module and not at the portable device; and,managing the lock device in accordance with the message; the secured module receiving plural messages from the portable device, with each of the plural messages including a sequence number which differs from the sequence number of its successor, the secured module checks conformity of the received messages using the sequence number and a counter maintained by the secured module; and wherein the secured module is connected to plural lock devices, and wherein the method further comprises receiving plural sequence numbers for each of the plural lock devices.