In-vehicle networking
A system and method for securing communication across an in-vehicle bus, includes establishing a connection between a gateway in a vehicle and the in-vehicle bus; generating a session key at the gateway within the vehicle; transmitting a public key certificate and ephemeral key to the gateway and an electronic control unit of the vehicle; generating a shared secret at the gateway and the electronic control unit, respectively; encrypting the session key with the shared secret at the gateway; receiving the encrypted session key through the in-vehicle bus at the electronic control unit; and decrypting the encrypted session key based on the shared secret generated at the electronic control unit.
1. A method for securing communication across an in-vehicle bus, comprising:
establishing a connection between a gateway in a vehicle and the in-vehicle bus;
generating a session key at the gateway in the vehicle;
transmitting a public key certificate and an ephemeral key to the gateway and an electronic control unit of the vehicle;
generating a shared secret at the gateway and the electronic control unit, respectively, the shared secret shared by the gateway and the electronic control unit;
encrypting the session key with the shared secret at the gateway;
receiving the encrypted session key through the in-vehicle bus at the electronic control unit; and
decrypting the encrypted session key using the shared secret generated at the electronic control unit.
2. The method of claim 1 , where the in-vehicle bus comprises a Controller Area Network utilizing packet sizes provisioned by an in-vehicle bus protocol.
3. The method of claim 1 , further comprising establishing a wireless connection between a node capable of communicating on the in-vehicle bus and a node remote from the vehicle.
4. The method of claim 1 , where the electronic control unit comprises a plurality of electronic control units consolidated into a domain controller.
5. The method of claim 1 , further comprising transmitting one of the public key certificate and ephemeral key from the gateway to the electronic control unit.
6. The method of claim 1 , further comprising transmitting one of the public key public key certificate and the ephemeral key from the electronic control unit to the gateway.
7. The method of claim 1 , where the session key is valid during only one communication session that occurs during an ignition cycle of the vehicle.
8. The method of claim 1 , where the session key is valid during only one communication session that occurs during a power cycle.
9. The method of claim 1 , further comprising transmitting data encrypted by the session key from the electronic control unit across the in-vehicle bus.
10. The method of claim 1 , where the electronic control unit communicates with a second vehicle using the encrypted session key.
11. The method of claim 1 , where the gateway includes a Root of Trust that securely stores the public key certificate and ephemeral key.
12. A non-transitory computer readable medium storing instructions that upon execution cause a system to:
establish a connection between a gateway in a vehicle and an in-vehicle bus;
generate a session key at the gateway in the vehicle;
transmit a public key certificate and an ephemeral key to the gateway and an electronic control unit of the vehicle;
generate a shared secret at the gateway and the electronic control unit, respectively, the shared secret shared by the gateway and the electronic control unit;
encrypt the session key with the shared secret at the gateway;
receive the encrypted session key over the in-vehicle bus at the electronic control unit; and
decrypt the encrypted session key using the shared secret generated at the electronic control unit.
13. The method of claim 1 , wherein the generating of the shared secret at the gateway comprises the gateway:
extracting a first public key from a public key certificate of the electronic control unit, and
generating, using a cryptographic operation, the shared secret using the first public key and the ephemeral key.
14. The method of claim 13 , wherein the generating of the shared secret at the electronic control unit comprises the electronic control unit:
extracting a second public key from a public key certificate of the gateway, and
generating, using the cryptographic operation, the shared secret using the second public key and the ephemeral key.
15. The method of claim 1 , wherein the shared secret is known only to the gateway and the electronic control unit.
16. The non-transitory computer readable medium of claim 12 , wherein the instructions upon execution cause the system to generate the shared secret at the electronic control unit by:
extracting, by the electronic control unit, a first public key from a public key certificate of the gateway, and
generating, by the electronic control unit using a cryptographic operation, the shared secret using the first public key and the ephemeral key.
17. The non-transitory computer readable medium of claim 16 , wherein the instructions upon execution cause the system to generate the shared secret at the gateway by:
extracting, by the gateway, a second public key from a public key certificate of the electronic control unit, and
generating, by the gateway using the cryptographic operation, the shared secret using the second public key and the ephemeral key.
18. The non-transitory computer readable medium of claim 12 , wherein the shared secret is known only to the gateway and the electronic control unit.
19. A vehicle comprising:
a gateway;
an electronic control unit; and
an in-vehicle bus connected to the gateway and the electronic control unit,
the gateway configured to:
receive a public key certificate of the electronic control unit and an ephemeral key, and
generate a session key,
generate a shared secret, and
encrypt the session key using the shared secret,
the electronic control unit configured to:
receive a public key certificate of the gateway and the ephemeral key,
receive the encrypted session key through the in-vehicle bus from the gateway,
generate the shared secret that is shared by the gateway and the electronic control unit, and
decrypt the encrypted session key using the shared secret generated by the electronic control unit.
20. The vehicle of claim 19 , wherein the gateway is configured to:
extract a first public key from the public key certificate of the electronic control unit, and
generate, using a cryptographic operation, the shared secret using the first public key and the ephemeral key.
21. The vehicle of claim 20 , wherein the electronic control unit is configured to:
extract a second public key from the public key certificate of the gateway, and
generate, using the cryptographic operation, the shared secret using the second public key and the ephemeral key.
22. The vehicle of claim 19 , wherein the shared secret is known only to the gateway and the electronic control unit.