VEHICLE NETWORK SYSTEM

• US 20140040992A1
• Filed: 03/02/2012
• Published: 02/06/2014
• Est. Priority Date: 03/04/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Inoue, Noriaki, Koide, Shohei, Ninagawa, Yuji
• Granted Patent: US 9,413,732 B2
• Time in Patent Office: Days
• US Class Current: 726/4
• CPC Class Codes: H04L 12/403 with centralised control, e.g. polling
• CPC Class Codes: H04L 2012/40215 Controller Area Network CAN
• CPC Class Codes: H04L 2012/40273 the transportation system being a vehicle
• CPC Class Codes: H04L 2209/84 Vehicles
• CPC Class Codes: H04L 63/0442 wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption cryptographic mechanisms or cryptographic arrangements for public-key encryption H04L9/30
• CPC Class Codes: H04L 63/06 for supporting key management in a packet data network cryptographic mechanisms or cryptographic arrangements for key management H04L9/08
• CPC Class Codes: H04L 63/0869 for achieving mutual authentication cryptographic mechanisms or cryptographic arrangements for mutual authentication H04L9/3273
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
• CPC Class Codes: H04L 9/3242 involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC
• CPC Class Codes: H04L 9/3247 involving digital signatures

Abstract

In a vehicle network system, a plurality of ECUs are network-connected. The plurality of ECUs include a first ECU that has set therein a secret key from among the secret key and a public key that form a pair and are set on the basis of initialization processing performed when the vehicle network system is created, and a second ECU that has set therein the public key. The second ECU adds, to a transmission signal, an authentication keyword created from the public key and information capable of specifying the second ECU and transmits the transmission signal with the authentication keyword added thereto to the network. The first ECU acquires the authentication keyword and estimates the reliability of the communication signal on the basis of the acquired authentication keyword and the secret key.

Claims

1. A vehicle network system, comprising:

a plurality of control units provided on a vehicle and network-connected to each other communicatively,

the plurality of control units including;

a first control unit that has set therein a secret key from among the secret key and a public key that form a pair and are set by execution of initialization processing for activating the system; and

a second control unit that has set therein the public key, wherein

the second control unit is configured to create authentication information from the public key and information capable of specifying the second control device unit, add the authentication information to a communication signal to be transmitted to another control unit, and transmit the communication signal with the authentication information added thereto to the network; and

the first control unit is configured to acquire the authentication information that has been added to the communication signal transmitted from the second control unit and estimate reliability of the communication signal on the basis of the acquired authentication information and the secret key.

2. The vehicle network system according to claim 1, wherein the second control unit is configured to divide the authentication information into a plurality of information pieces, successively add the divided authentication information that has been obtained by division to communication signals, and transmit the communication signals with the divided authentication information added thereto;

and

the first control unit is configured to receive successively the communication signals, reconfigure the authentication information before the division from the divided authentication information and estimate reliability of the communication signals on the basis of the reconfigured authentication information.

3. The vehicle network system according to claim 1, wherein

the first control unit is configured to generate the secret key and the public key by execution of the initialization processing and sets the secret key to the first control unit itself and sets the public key to the second control unit.

4. The vehicle network system according to claim 3, wherein the first control unit sets the public key to the second control unit via the network.

5. The vehicle network system according to claim 1, wherein the second control unit creates the authentication information at a timing at which the public key is set.

6. The vehicle network system according to any one of claim 1, wherein after creating the authentication information, the second control unit deletes the public key that has been set.

7. The vehicle network system according to claim 1, wherein the second control unit transmits the authentication information to the network prior to transmitting the communication signal each time the vehicle network system is started, and the first control unit is configured to acquire and store the authentication information that has been received prior to receiving the communication signal from the second control unit and to estimate reliability of the communication signal by comparing the stored authentication information with the authentication information added to the communication signal.

8. The vehicle network system according to claim 1, wherein the first control unit is configured to prohibit use of a communication signal transmitted by the second control unit in the vehicle network system when determining that the communication signal is unreliable.

9. A vehicle network system, comprising:

a plurality of control units provided on a vehicle and network-connected to each other communicatively,

the plurality of control units including;

a first control unit that has set therein a secret key from among the secret key and a public key that form a pair and are set by execution of initialization processing for activating the system; and

a second control unit that has set therein the public key, wherein

the first control unit is configured to transmit a communication signal to another control unit via the network and also transmit an authentication signal created on the basis of the secret key and original authentication data generated on the basis of the communication signal; and

the second control unit is configured to receive the communication signal and the authentication signal and estimate reliability of the communication signal on the basis of comparison of reproduced authentication data generated on the basis of the received communication signal and decoded authentication data decoded on the basis of the authentication signal and the public key.

10. The vehicle network system according to claim 9, wherein the first control unit is configured to generate the authentication signal by encrypting, with the secret key, the original authentication data calculated by applying a hash function to the communication signal, and the second control unit is configured to calculate the reproduced authentication data by applying the hash function to the received communication signal and estimate reliability of the communication signal on the basis of comparison of the reproduced authentication data with decoded authentication data obtained by decoding the authentication signal.

11. The vehicle network system according to claim 9, wherein the first control unit is configured to generate the secret key and the public key by execution of the initialization processing and sets the secret key to the first control unit itself and sets the public key to the second control unit.

12. The vehicle network system according to claim 11, wherein the first control unit sets the public key to the second control unit via the network.