Vehicle system and key distribution method

Patent metadata

Field	Value
Publication number	US-10812261-B2
Application number	US-201916597264-A
Country	US
Kind code	B2
Filing date	Oct 9, 2019
Priority date	Apr 27, 2017
Publication date	Oct 20, 2020
Grant date	Oct 20, 2020

Abstract

A vehicle system includes a plurality of electronic control devices respectively includes a first processor configured to control each unit of a vehicle; and a management electronic control device that includes a second processor configured to manage the plurality of electronic control devices, wherein when an encryption key used to verify a message is updated to another encryption key, the second processor transmits a first message that includes a controller area network identifier (CAN-ID) that identifies the message and a second message that includes the another encryption key to a network, and when the CAN-ID of the message included in the first message is a CAN-ID to be processed, the first processor updates the encryption key used to verify the message to the another encryption key included in the second message.

First claim

What is claimed is:

1. A vehicle system comprising:
a plurality of electronic control devices respectively includes a first processor configured to control each unit of a vehicle; and
a management electronic control device that includes a second processor configured to manage the plurality of electronic control devices, wherein
when an encryption key used to verify a message is updated to another encryption key, the second processor transmits a first message that includes a controller area network identifier (CAN-ID) that identifies the message and a second message that includes the another encryption key to a network, and
when the CAN-ID of the message included in the first message is a CAN-ID to be processed, the first processor updates the encryption key used to verify the message to the another encryption key included in the second message.

2. The vehicle system according to claim 1 , wherein
when requesting to update the encryption key used to verify the message, a first electronic control device of the plurality of electronic control devices transmits a third message including the CAN-ID for identifying the message to the network.

3. The vehicle system according to claim 1 ,
wherein the second processor is configured to generate the another encryption key when a predetermined period has elapsed from a generation time of the encryption key.

4. The vehicle system according to claim 1 ,
wherein the first message includes an unique identifier (UID) assigned to a target electronic control device that updates the encryption key, and a slot where the encryption key is stored.

5. The vehicle system according to claim 4 ,
wherein the first processor included in an electronic control device of the plurality of electronic control devices is configured to acquire the second message when the UID included in the first message matches with the UID assigned to the electronic control device.

6. The vehicle system according to claim 1 ,
wherein the second message includes counter value for preventing a replay.

7. A key distribution method executed by a vehicle system that includes a plurality of electronic control devices used to control each unit of a vehicle and a management electronic control device configured to manage the plurality of electronic control devices, the key distribution method comprising:
when an encryption key used to verify a message is updated to another encryption key, transmitting, by a second processor included in the management electronic control device, a first message including a controller area network identifier (CAN-ID) that identifies the message and a second message that includes the another encryption key; and
when the CAN-ID of the message included in the first message is a CAN-ID to be processed, updating, by a first processor included in at least one of the plurality of electronic control devices, the encryption key used to verify the message to the another encryption key included in the second message.

8. The key distribution method according to claim 7 , further comprising
generating, by the second processor, the another encryption key when a predetermined period has elapsed from a generation time of the encryption key.

9. The key distribution method according to claim 7 ,
wherein the first message includes an unique identifier (UID) assigned to a target electronic control device that updates the encryption key, and a slot where the encryption key is stored.

10. The key distribution method according to claim 7 ,
wherein the second message includes counter value for preventing a replay.

Assignees

• Fujitsu Ltd

Inventors

• Usui Kenta
• Abe Yasuhiko
• Suzuki Naoki

Classifications

• H04L12/40 Primary

  Bus networks · CPC title

• G08G1/092

  Coding or decoding of the information · CPC title

• H04L9/0891 Primary

  Revocation or update of secret information, e.g. encryption key update or rekeying · CPC title

• H04L9/0822

  using key encryption key · CPC title

• H04L63/068

  using time-dependent keys, e.g. periodically changing keys (cryptographic mechanisms or cryptographic arrangements for controlling usage of secret information H04L9/088) · CPC title