Patent application EP18165786A (EP), filed 2018-04-04
Publication number: EP3386163A1
Title: APPARATUS FOR USE IN A CAN SYSTEM
Abstract: A CAN device is provided with an encryption function and a decryption function. The encryption function allows messages to be encrypted and put onto a CAN bus. The decryption function allow the messages on the CAN bus to be decrypted. The encryption and decryption functions share keys which change over the course of time.
IPC codes: H04L  29/    06            A I
H04L  29/    08            A I
H04L  67/    12            A I
H04L   9/    40            A I
Claims: number: 1
text: An apparatus in a device, said device being for use in a system operating in accordance with a CAN protocol, said apparatus comprising:
number: 2
text: Apparatus as claimed in claim 1, comprising a coding function configured to scramble at least a part of said data to be output.
number: 3
text: Apparatus as claimed in claim 2, wherein said at least a part of data to be scrambled comprises CAN identity data and CAN payload data.
number: 4
text: An apparatus in a device, said device being for use in a system operating in accordance with a CAN protocol, said apparatus comprising:
number: 5
text: Apparatus as claimed in claim 4, comprising a decoding function configured to descramble at least a part of said decrypted output.
number: 6
text: Apparatus as claimed in claim 5, wherein said at least a part of said decrypted output to be descrambled comprises scrambled CAN identity data and scrambled CAN payload data.
number: 7
text: Apparatus as claimed in any preceding claim, comprising a counter, said counter providing a count value to:
number: 8
text: Apparatus as claimed in claim 7, wherein said coding function is configured to determine a value of a bit of said count value and in dependence on said value select a next not already selected bit of CAN identity data or a next not already selected bit of the CAN payload data.
number: 9
text: Apparatus as claimed in claim 7, wherein said decoding function is configured to determine a value of a bit of said count value with respect to a flag and in dependence on said value select a next not already selected bit of CAN identity data or a next not already selected bit of the CAN payload data.
number: 10
text: Apparatus as claimed in any of claims 7 to 9, wherein said coding function and/or said decoding function are configured to receive a count value from said counter to control said scrambling and said unscrambling.
number: 11
text: Apparatus as claimed in any of claims 7 to 10, wherein a current count value of said counter is used by said coding function and/or said decoding function, and wherein a previous count value of said counter is used to control said encryption output and/or said decryption output.
number: 12
text: Apparatus as claimed in any preceding claim, wherein if a trusted flag is set:
number: 13
text: A method for use in a system operating in accordance with a CAN protocol, said method comprising:
number: 14
text: A method for use in a system operating in accordance with a CAN protocol, said method comprising:
Office action: search_report, dated 2018-10-10
Rejection reasons: novelty_epc_54
Prior art cited: ref_id: US2016315766A1
ref_type: patent
severity: background
ref_id: US2013219170A1
ref_type: patent
severity: background
ref_id: US2016219051A1
ref_type: patent
severity: background
ref_id: US2013219170
ref_type: patent
severity: novelty_destroying
ref_id: US2016219051
ref_type: patent
severity: novelty_destroying
ref_id: US2016315766
ref_type: patent
severity: novelty_destroying
Final disposition: pending (2018-10-10)