Method for providing an encryption key to an on-board computer of a vehicle

Abstract

The present invention relates to a method and device for providing an encryption key to a first and a second on-board computer of a vehicle by a mounted device. The method comprises the following steps: - reception (41), by the first computer, of a first signal emitted by the mounted device, said first signal carrying data representing a request to initiate a learning process for a first encryption key; - initiation (42) by the first computer of the learning process for the first encryption key; - emission (43), by the first computer, of a second signal carrying data representing a request to initiate a learning process for a second encryption key; - reception (44), by the second computer, of the second signal; and - initiation (45), by the second computer, of the learning process for the second encryption key. Figure for the abstract: Figure 4

Description

Title of the invention: Method for providing an encryption key to an on-board computer of a vehicle Technical field

[0001] The present invention relates to the cybersecurity of computers on board a vehicle, in particular a motor vehicle. More particularly, the present invention relates to the provision of encryption keys used by computers on board a vehicle for the secure implementation of functions linked to the operation of components of a vehicle. Technological background

[0002] Contemporary vehicles have a number of peripherals incorporating computers, each of which performs one or more functions, such as, for example, a driving assistance management function, a traction control function, an electronic brake distribution function, or even an actuator control function to ensure the optimal operation of a thermal, hybrid or electric powertrain.

[0003] These computers are connected to each other via a multiplexed serial data bus of the CAN type (from the English "Controller Area Network" or in French "Network of controllers"). CAN type data buses exist in different versions, such as the CAN LS bus (from English "Low Speed", in French "Faible vitesse", the maximum flow rate being approximately 125Kbit / s), the CAN HS bus (from English "High Speed", in French "Grande vitesse", the maximum flow rate being approximately 1Mbit / s), the CAN FD bus (from English "Flexible Data-Rate", in French "Débit de données Flexible" flow rate up to 15Mbit / s).

[0004] Some of these functions ensure the safety of the vehicle. These are sometimes referred to as cybersecurity functions. These cybersecurity functions require secure exchanges of control signals between a first computer receiving control signals and a second computer transmitting these control signals.

[0005] Among the cybersecurity functions, mention may be made of the electronic immobilization function of the vehicle which requires authentication of the second computer with the first computer prior to the exchange of control signals between the second computer transmitting the control signals and the first computer receiving these control signals. The first computer may be for example an MCU (from the English "Machine Control Unit") or a CMM (Multifunction Engine Control) or RMCU (from the English "Rear Machine Control Unit") depending on the diversity of the vehicle's powertrain (thermal / hybrid / electric), and the second computer can be a VSM (Vehicle Supervisor Module).

[0006] We can also cite the electronic anti-theft function of the vehicle which requires authentication of the second computer with the first computer prior to the exchange of control signals between the second computer transmitting the control signals and the first computer receiving these control signals. The first computer can be, for example a TCU (from the English "Transmission Control Unit") or EPLU (from the English "Electrical Park Lock Unit") depending on the diversity of the vehicle's powertrain (thermal / hybrid with mechanical or electric gearbox) and the second computer can be a VSM.

[0007] [Fig.l] schematically illustrates a process of authentication of a second computer 12 with a first computer 11.

[0008] The first computer 11 transmits a signal 13 to the second computer 12. The signal 13 carries a random data item 131 also called a seed. The second computer 12 calculates an authentication data item from the random data item 131 and an encryption key used by the second computer 12 and transmits a signal 14 carrying the authentication data item to the first computer 11. The first computer 11 calculates an authentication data item from the random data item 131 and an encryption key that it uses and compares the authentication data item carried by the received signal 14 and the authentication data item that it has just calculated.If these authentication data are identical then the first computer 11 operates according to an 'unlocked' operating mode, that is to say that any control signal 15 emitted by the second computer 12 to the first computer 11 is taken into account by the first computer 11. If these authentication data are not identical or if the first computer 11 does not receive the signal 14, then the first computer 11 operates according to a 'locked' operating mode, that is to say that any control signal 15 emitted by the second computer 12 to the first computer 11 is not taken into account by the first computer 11.

[0009] The first computer 11 receiving control signals 15 can operate in either the 'locked' operating mode or the 'unlocked' operating mode.

[0010] The principle of the authentication process of the second computer 12 with the first computer 11 ([Fig.l]) requires that the first computer 11 and the second computer 12 share the same encryption key.

[0011] This encryption key is provided to the first computer 11 and to the second cal culator 12 by an encryption key supply method which requires a transmission of an encryption key from a device unloaded from the vehicle to the first computer 11 and a transmission of this encryption key from the device unloaded from the vehicle to the second computer 12. The encryption key is obtained from a data server in communication with the unloaded device.

[0012] It may happen that the offloaded device is not able to transmit the encryption key to one (or both) computer(s) due, for example, to a break in the connection between the offloaded device and the data server.

[0013] It is necessary to improve current encryption key provisioning methods to provide an encryption key to a computer even if the connection between the landed device and the data server configured to provide the encryption key is interrupted. Abstract of the present invention

[0014] An object of the present invention is to solve at least one of the problems of the technological background described above.

[0015] Another object of the present invention is to improve the processes for providing an encryption key to an on-board computer of a vehicle.

[0016] According to a first aspect, the present invention relates to a method for providing an encryption key to a first and a second on-board computer of a vehicle by an off-board device, comprising the following steps: - reception, by the first computer, of a first signal emitted by the unloaded device, said first signal carrying data representative of a request to launch a process of learning a first encryption key and carrying data defining the first encryption key; - launch by the first computer of the learning process of the first encryption key; - transmission, by the first computer and to the second computer, of a second signal carrying data representative of a request to launch a process of learning a second encryption key and carrying data defining the second encryption key; - reception, by the second computer, of the second signal; and - launch, by the second computer, of the learning process of the second encryption key.

[0017] The method makes it possible to compensate for a communication break between the landed device and the data server configured to provide a first encryption key which must be learned by a second computer by transmitting this first encryption key from the first computer which then acts as the encryption key provider for the second computer.

[0018] The first computer replaces the landed device by relaying the signals it receives from the landed device to the second computer and the signals it receives from the second computer to the landed device.

[0019] Thus, the method allows the second computer to learn an encryption key without direct communication being established between this second computer and the off-loaded device.

[0020] The method is advantageous because it only requires adaptation of the computers (more precisely of their communications interfaces). The off-loaded device and the data server of the state of the art remain unchanged for the implementation of the present invention.

[0021] According to a particular and non-limiting exemplary embodiment, the method further comprises a step of reception, by the first computer, of a third signal emitted periodically by the second computer, said third signal carrying data representative of a progress state of the process of learning the second encryption key launched by the second computer.

[0022] According to a particular and non-limiting exemplary embodiment, the method further comprises the following steps: - reception, by the first computer, of a fourth signal emitted periodically by the remote device, said fourth signal carrying data representative of a request for progress status of the encryption key learning process; and - transmission, by the first computer, of a fifth signal to the remote device, said fifth signal carrying data representative of a progress status of the learning process of the first encryption key launched by the first computer and of the progress status of the learning process of the second encryption key carried by the fourth signal received.

[0023] According to a particular and non-limiting exemplary embodiment, the first and second encryption keys are identical.

[0024] This exemplary embodiment is advantageous because it allows the propagation of the same encryption key to several computers as soon as this key is learned by one of these computers.

[0025] According to a particular and non-limiting exemplary embodiment, the first and second encryption keys are different and the method further comprises the following steps: - generation of the second key by the first calculator; - launch by the first computer of the learning process of the second encryption key; - said fifth signal carrying data representative of a progress state of the learning process of the first and second encryption keys by the first computer and of the progress state of the learning process of the second encryption key by the second computer.

[0026] This exemplary embodiment is advantageous because it allows a computer to learn two encryption keys: one received by the off-loaded device and another generated by this computer. The learning of two encryption keys by the same computer can prove particularly advantageous. Indeed, in a context of insufficient cybersecurity of the off-loaded infrastructures, it is not uncommon for a remote encryption key server to be able to distribute only a limited number of encryption keys compared to the number of inter-computer communications that one seeks to secure. For example, in the same vehicle, the communication between two computers A and B as well as the communication between two computers A and C must be secured. Two encryption keys must therefore be learned by computer A. However, certain restrictions prohibit encryption key servers from delivering two encryption keys to the same computer.This exemplary embodiment is advantageous because a computer A can launch a learning process of a first encryption key received from the unloaded device and a second encryption key generated by this computer A.

[0027] According to a particular and non-limiting exemplary embodiment, the second encryption key is generated as a function of the first encryption key.

[0028] According to a second aspect, the present invention relates to a device for providing an encryption key to a first and a second on-board computer of a vehicle by an off-board device, the device comprising a memory associated with a processor configured for implementing the steps of the method according to the first aspect of the present invention.

[0029] According to a third aspect, the present invention relates to a vehicle, for example of the automobile type, comprising a device according to the second aspect of the present invention.

[0030] According to a fourth aspect, the present invention relates to a computer program which comprises instructions adapted for executing the steps of the method according to the first aspect of the present invention, in particular when the computer program is executed by at least one processor.

[0031] Such a computer program may use any programming language, and be in the form of source code, object code, or intermediate code between source code and object code, such as in a partially compiled form, or in any other desirable form.

[0032] According to a fifth aspect, the present invention relates to a computer-readable recording medium on which is recorded a computer program comprising instructions for carrying out the steps of the method according to the first aspect of the present invention.

[0033] On the one hand, the recording medium may be any entity or device capable of storing the program. For example, the medium may comprise a storage means, such as a ROM memory, a RAM memory, a CD-ROM or a microelectronic circuit type ROM memory, or a magnetic recording means or a hard disk.

[0034] Furthermore, this recording medium may also be a transmissible medium such as an electrical or optical signal, such a signal being able to be conveyed via an electrical or optical cable, by conventional or hertzian radio or by self-directed laser beam or by other means. The computer program according to the present invention may in particular be downloaded from an Internet-type network.

[0035] Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to perform or to be used in performing the method in question. Brief description of the figures

[0036] Other characteristics and advantages of the present invention will emerge from the description of the particular and non-limiting exemplary embodiments of the present invention below, with reference to the appended figures 1 to 4, in which:

[0037] [Fig-1] schematically illustrates a process of authentication of a second cal culator with a first calculator;

[0038] [Fig.2] illustrates an environment for implementing a method of providing an encryption key to a first and a second on-board computer of a vehicle from an off-board device, according to a particular and non-limiting exemplary embodiment of the present invention;

[0039] [Fig.3] schematically illustrates a device configured to provide an encryption key to a first and a second on-board computer of a vehicle from an off-board device, according to a particular and non-limiting exemplary embodiment of the present invention;

[0040] [Fig.4] illustrates a flowchart of the different steps of a method for providing an encryption key to a first and a second on-board computer of a vehicle from an off-board device, according to a particular and non-limiting exemplary embodiment of the present invention. Description of examples of implementation

[0041] A method and device for providing an encryption key to a first and a second second on-board computer of a vehicle from an off-board device will now be described in what follows with joint reference to figures 2 to 4. The same elements are identified with the same reference signs throughout the description which follows.

[0042] The terms "first(s)", "second(s)" (or "first(s)", "second(s)"), etc. are used in this document by arbitrary convention to enable different elements (such as operations, means, etc.) implemented in the embodiments described below to be identified and distinguished. Such elements may be distinct or correspond to a single element, depending on the embodiment.

[0043] [Fig.2] illustrates an environment for implementing a method for providing an encryption key to a first computer 11 and to a second computer 12 on board a vehicle from an off-board device 16 according to a particular and non-limiting example embodiment of the present invention.

[0044] The off-loaded device 16 may be, for example, a diagnostic device commonly used during the assembly phases of the vehicle in the factory or by an after-sales service.

[0045] The onboard device 16 comprises a communication interface which is configured to establish a communication channel of a first wired or non-wired communication network with a data server 18 of the “cloud” 17. The data server 18 advantageously corresponds to a device configured to provide encryption keys to onboard vehicle computers.

[0046] The first communication network can be wired, such as the Internet, for example.

[0047] The first communication network may be of the cellular type, for example a LTE (Long-Term Evolution), LTE-Advanced, LTE 4G or 5G network; or a Wi-Fi communication system according to IEEE 802.11, for example according to IEEE 802.lin or IEEE 802.1 lac.

[0048] The first communication network may comprise a wired portion and a wireless portion.

[0049] According to a particular and non-limiting exemplary embodiment, signals can be exchanged between the landed device 16 and the first computer 11 via a wired or wireless communication channel of a second communication network.

[0050] The second communication network can be wired, such as the Internet, for example.

[0051] The second communication network may be of the cellular type, for example a Wi-Fi communication network according to IEEE 802.11, for example according to IEEE 802.lin or IEEE 802.1 lac.

[0052] According to a particular and non-limiting exemplary embodiment, signals can be exchanged between the first computer 11 and the second computer 12 via a bus CAN data.

[0053] A process for providing an encryption key to the first computer 11 and to the second computer 12 on board a vehicle from the off-board device 16 is advantageously implemented by the first computer 11 and by the second computer 12.

[0054] In a first operation, a first signal 201 emitted by the landed device 16 is received by the first computer 11. The first signal 201 carries data representative of a request to launch a process for learning a first encryption key 211 and carries data defining the first encryption key 211.

[0055] In a second operation, a process of learning the first encryption key 211 is launched by the first computer 11.

[0056] The processes for learning an encryption key by a computer are widely known in the state of the art. Their purpose is for an encryption key to be memorized by this computer.

[0057] According to a variant of the first operation, the first computer 11 can emit a signal 206 carrying data which indicates that the process of learning the first encryption key 211 has been launched by the first computer 11.

[0058] In a third operation, a second signal 202 is emitted by the first computer 11 and sent to the second computer 12. The second signal 202 carries data representative of a request to launch a process for learning a second encryption key 212 and carries information defining a second encryption key 212.

[0059] In a fourth operation, the second signal 202 is received by the second computer 12.

[0060] In a fifth operation, the second computer 12 launches a process of learning the second encryption key 212.

[0061] According to a particular and non-limiting exemplary embodiment, in a sixth operation, the first computer 11 periodically receives a third signal 203 emitted by the second computer 12. The third signal 203 carries data representative of a progress state of the learning process of the second encryption key 212 launched by the second computer 12.

[0062] According to a particular and non-limiting exemplary embodiment, the process further comprises a seventh and an eighth operation.

[0063] In the seventh operation, the first computer 11 receives a fourth signal 204 transmitted periodically by the remote device 16. The fourth signal 204 carries data representative of a request for progress status of the encryption key learning process.

[0064] In the eighth operation, the first computer 11 transmits a fifth signal 205 to the remote device 16. The fifth signal 205 carries data representative of a progress state of the learning process of the first encryption key 211 launched by the first computer 11 and of the progress state of the learning process of the second encryption key 212 carried by the third signal 203 received.

[0065] According to a particular and non-limiting exemplary embodiment, the first and second encryption keys are identical.

[0066] According to a particular and non-limiting exemplary embodiment, the first and second encryption keys are different.

[0067] According to a particular and non-limiting exemplary embodiment, the second encryption key 212 is generated as a function of the first encryption key 211.

[0068] According to a particular and non-limiting exemplary embodiment, the process further comprises a ninth and a tenth operation.

[0069] In the ninth operation, the second encryption key 212 is generated by the first computer 11.

[0070] In the tenth operation, the first computer 11 launches a process of learning the second encryption key 212. The fifth signal 205 then carries data representative of a progress state of the processes of learning the first and second encryption keys launched by the first computer 11 and of the progress state of the process of learning the second encryption key launched by the second computer 12.

[0071] According to a particular and non-limiting exemplary embodiment, the second signal 202 and the third signal 203 are transmitted via a CAN type data bus connecting the first computer 11 and the second computer 12.

[0072] The use of CAN buses facilitates the implementation of the present invention because CAN buses are widely deployed in a vehicle for the communication of signals between computers.

[0073] According to a particular and non-limiting exemplary embodiment, the first 201, fourth 204 and fifth 205 signals and the signal 206 carry data formatted according to the UDS protocol (from the English Unified Diagnostic Services).

[0074] The use of the UDS protocol facilitates the implementation of the present invention because the UDS protocol is already used for the implementation of current process exchanges for providing encryption keys between the off-board device 16 and on-board computers of a vehicle such as the first computer 11.

[0075] For example, two types of control routines (in English "Routine Control") of the UDS protocol can be used for the implementation of the signals exchanged between the first computer 11, the second computer 12 and the landed device 16: a request routine for launching a learning process or progress status of an encryption key learning process and a response routine for progress status of an encryption key learning process.

[0076] Table 1 illustrates an example of a UDS protocol encryption key learning process launch or learning process progress request routine. [Tables 1] 201 204 RoutineControl 0x31 0x3 SupressPosRspMsgindicationBit OxXX OxXX RoutineControlT ype 0x1 0x3 CLE_CRYPTO programming identifier OxXXXX OxXXXX CLE-CRYPTO OxXXXXXXXX [Tables 2] RoutineControl 0x71 Echo of bit 2 of the request OxXX CLE_CRYPTO programming identifier OxXXXX Code Table_XXXX_RoutinePosRep OxOX Contenu Table_XXXX_RoutinePosRep 0x00

[0077] According to the exemplary embodiment in which the first signal 201 carries data formatted according to the UDS protocol, in the first operation, the first signal 201 carries data representative of parameters of the table 1 column '201' which represent a request to launch an encryption key learning process. The parameter 'RoutineControl' equal to 0x31 indicates this request. The parameter 'SupressPosRspMsgindicationBit' equal to OxXX indicates an identifier of this request. The parameter 'RoutineControlType' equal to 0x1 to indicate that the request is a request to launch an encryption key learning process. The parameter 'CLE_CRYPTO programming identifier' indicates an identifier of the first encryption key 211. The parameter 'CLE-CRYPTO' defines the first encryption key 211.

[0078] According to a variant of the first operation, the signal 206 carries data formatted according to the UDS protocol. The signal 206 carries data representative of parameters of table 2. The parameter 'RoutineControl' equal to 0x71 indicates a response to the request carried by signal 201. The parameter 'Echo of bit 2 of the request' equal to OxXX indicates the identifier of the request. The parameters 'Code Table_XXXX_RoutinePosRep' and 'Content Table_XXXX_RoutinePosRep' indicate a progress status of the learning process launched by the first computer 11.

[0079] According to the exemplary embodiment in which the first signal 201 carries data formatted according to the UDS protocol, in the third operation, the second signal 202 carries data representative of the parameter 'RoutineControlType' equal to 0x1 which indicates a request to launch an encryption learning process and of the parameter 'CLE-CRYPTO' which defines the second encryption key 212.

[0080] According to the exemplary embodiment in which the fourth signal 204 carries data formatted according to the UDS protocol, in the seventh operation, the fourth signal 204 carries data representative of parameters of table 1 column '204' which represent the request for progress status of the encryption key learning process. The parameter 'RoutineControl' equal to 0x31 indicates a periodic request. The parameter 'RoutineControlType' equal to 0x3 indicates that the request is a request for progress status of the encryption key learning process. The parameter 'CLE_CRYPTO programming identifier' indicates an identifier of the encryption key, in this case the first encryption key 211 or the second encryption key 212.

[0081] According to the exemplary embodiment in which the fifth signal 205 carries data formatted according to the UDS protocol. In the eighth operation, the signal 205 carries data representative of parameters of the table 2. The parameter 'RoutineControl' equal to 0x71 indicates a response to the request carried by the fourth signal 204. The parameter 'Echo of bit 2 of the request' equal to OxXX indicates the identifier of the request. The parameters 'Code Table_XXXX_RoutinePosRep' and 'Content Table_XXXX_RoutinePosRep' indicate a progress status of the learning processes launched by the first computer 11 and by the second computer 12.

[0082] The values ​​of the parameters 'Code Table_XXXX_RoutinePosRep' and 'Content Table_XXXX_RoutinePosRep' depend on the value of the second encryption key 212.

[0083] If the second encryption key 212 is identical to the first encryption key 211 then the values ​​of the parameters 'Code Table_XXXX_RoutinePosRep' and 'Content Table_XXXX_RoutinePosRep' are fixed by table 3. [Tables 3] Progress status learning key 211 calculator 11 Progress status learning key 212 calculator 12 Code Table_XXXX_ RoutinePosRep Content Table_XXXX_ RoutinePosRep success success success no problem success failure cause XX failure Cause: XX failure cause YY success failure Cause: YY failure cause YY failure cause XX failure Cause: XX+YY

[0084] The terms 'success', 'failure', 'cause XX', 'cause YY', 'cause XX+YY' and 'no problem', are translated into hexadecimal codes.

[0085] The term 'success' indicates that an encryption key has been learned by a computer. The term 'failure' indicates that an encryption key has not been learned by a computer. The term 'cause XX', cause YY' indicates one cause of failure of learning an encryption key by a computer, each cause identifying the computer that failed and the reason for this failure. The terms 'cause XX+YY' two causes of failure of learning an encryption key by two computers, each cause identifying the computer that failed and the reason for this failure.

[0086] If the second encryption key 212 is different from the first encryption key 211 then the values ​​of the parameters 'Code Table_XXXX_RoutinePosRep' and 'Content Table_XXXX_RoutinePosRep' are fixed by table 4. [Tables 4] Progress status learning key 211 calculator 11 Progress status learning key 212 calculator 11 Progress status learning key 212 calculator 12 Code Table_XXXX_ RoutinePosRep Content Table_XXXX_ RoutinePosRep success success success success no problem success success failure cause YY failure Cause: YY success failure cause XX success failure Cause: XX success failure cause XX failure cause YY failure Cause: XX+YY failure cause WW success success failure Cause: WW failure cause WW success failure cause YY failure Cause: YY+WW failure cause WW failure cause XX success failure Cause: XX+WW failure cause WW failure cause XX failure cause YY failure Cause: WW+XX+YY

[0087] The terms 'success', 'failure', 'cause XX', 'cause YY', 'cause WW', 'cause XX+YY', 'cause XX+WW', 'cause 'XX+YY+WW' and 'no problem', are translated into hexadecimal codes.

[0088] The term 'success' indicates that an encryption key was learned by a computer. The term 'failure' indicates that an encryption key was not learned by a computer. The term 'cause XX', cause YY' indicates one cause of failure of learning an encryption key by a computer, each cause identifying the computer that failed and the reason for this failure. The terms 'cause XX+YY', 'cause XX+WW', 'cause YY+WW' indicate two causes of failure of learning an encryption key by two computers, each cause identifying the computer that failed and the reason for this failure. The term 'cause XX+YY+WW' indicates three causes of failure of learning an encryption key by two computers, each cause identifying the computer that failed and the reason for this failure.

[0089] [Fig.3] schematically illustrates a device 3 configured to provide at least an encryption key to an on-board computer of a vehicle from an off-board device, according to a particular and non-limiting exemplary embodiment of the present invention. The device 3 corresponds to a device on board the vehicle comprising at least two computers.

[0090] The device 3 is for example configured for the implementation of the operations described with regard to [Fig. 2] and / or the steps of the method described with regard to [Fig. 4]. Examples of such a device 3 include, but are not limited to, on-board electronic equipment such as an on-board computer of a vehicle or an electronic calculator such as an ECU (“Electronic Control Unit”). The elements of the device 3, individually or in combination, may be integrated in a single integrated circuit, in several integrated circuits, and / or in discrete components. The device 3 may be produced in the form of electronic circuits or software (or computer) modules or even a combination of electronic circuits and software modules.

[0091] The device 3 comprises one (or more) processor(s) 30 configured to execute instructions for carrying out the steps of the method and / or for executing the instructions of the software(s) embedded in the device 3. The processor 30 may include integrated memory, an input / output interface, and various circuits known to those skilled in the art. The device 3 further comprises at least one memory 31 corresponding for example to a volatile and / or non-volatile memory and / or comprises a memory storage device which may comprise volatile and / or non-volatile memory, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic or optical disk.

[0092] The computer code of the embedded software(s) comprising the instructions to be loaded and executed by the processor is for example stored in the memory 31.

[0093] According to various particular and non-limiting embodiments, the device 3 is coupled in communication with other similar devices or systems and / or with communication devices, for example a TCU (from the English “Telematic Control Unit” or in French “Telematic Control Unit”), for example via a communication bus or through dedicated input / output ports.

[0094] According to a particular and non-limiting exemplary embodiment, the device 3 comprises a block 32 of interface elements for communicating with external devices, for example a remote server or a diagnostic device, other nodes of the ad hoc network. The interface elements of the block 32 comprise one or more of the following interfaces: - RF radio frequency interface, for example Wi-Fi® type (according to IEEE 802.11), for example in the 2.4 or 5 GHz frequency bands, or Bluetooth® type (according to IEEE 802.15.1), in the 2.4 GHz frequency band, or Sigfox type using UBN (Ultra Narrow Band) radio technology, or LoRa in the 868 MHz frequency band, LTE (Long-Term Evolution), LTE-Advanced; - USB interface (from the English “Universal Serial Bus” or “Universal Serial Bus” in French); - HDMI interface (from the English “High Definition Multimedia Interface” or “High Definition Multimedia Interface” in French); - LIN interface (from the English “Local Interconnect Network”).

[0095] According to another particular and non-limiting exemplary embodiment, the device 3 comprises a communication interface 33 which makes it possible to establish communication with other devices (such as other on-board computers of the vehicle) via a communication channel 331. The communication interface 33 corresponds for example to a transmitter configured to transmit and receive information and / or data via the communication channel 331. The communication interface 33 corresponds for example to a wired network of the CAN, FlexRay (standardized by the ISO 17458 standard) or Ethernet (standardized by the ISO / IEC 802-3 standard) type.

[0096] According to a particular and non-limiting exemplary embodiment, the device 3 can provide output signals to one or more external devices, such as a display screen 34, touch-sensitive or not, one or more speakers 35 and / or other peripherals 36 via output interfaces 37, 38, 39 respectively. According to a variant, one or other of the external devices is integrated into the device 3.

[0097] [Fig.4] illustrates a flowchart of the different steps of a method for providing an encryption key to an on-board computer of a vehicle from an off-board device, according to a particular and non-limiting exemplary embodiment of the present invention.

[0098] The method is for example implemented by a device on board the vehicle or by the device 3 of [Fig.3].

[0099] In a first step 41, a first signal 201 transmitted by the landed device 16 is received by the first computer 11. The first signal 201 carries data representative of a request to launch a process for learning a first encryption key 211 and carries data defining the first encryption key 211.

[0100] In a second step 42, a process of learning the first encryption key 211 is launched by the first computer 11.

[0101] In a third step 43, a second signal 202 is emitted by the first cal culator 11 and to the second computer 12. The second signal 202 carries data representative of a request to launch a process of learning a second encryption key 212 and carries information defining a second encryption key 212.

[0102] In a fourth step 44, the second signal 202 is received by the second computer 12.

[0103] In a fifth step 45, the second computer 12 launches a process of learning the second encryption key 212.

[0104] In a sixth step 46 (optional), the first computer 11 periodically receives a third signal 203 emitted by the second computer 12. The third signal 203 carries data representative of a progress status of the learning process of the second encryption key 212 launched by the second computer 12.

[0105] In a seventh step 47 (optional), the first computer 11 receives a fourth signal 204 transmitted periodically by the remote device 16. The fourth signal 204 carries data representative of a request for progress status of the encryption key learning process.

[0106] In an eighth step 48 (optional), the first computer 11 transmits a fifth signal 205 to the remote device 16. The fifth signal 205 carries data representative of a progress state of the learning process of the first encryption key 211 launched by the first computer 11 and of the progress state of the learning process of the second encryption key 212 carried by the third signal 203 received.

[0107] In a ninth step 49 (optional), the second encryption key 212 is generated by the first computer 11.

[0108] In a tenth step 50 (optional), the first computer 11 launches a process of learning the second encryption key 212. The fifth signal 205 then carries data representative of a progress state of the processes of learning the first and second encryption keys launched by the first computer 11 and of the progress state of the process of learning the second encryption key launched by the second computer 12.

[0109] Of course, the present invention is not limited to the exemplary embodiments described above but extends to a method for providing an encryption key to an on-board computer of a vehicle from an off-board device, which would include secondary steps without thereby departing from the scope of the present invention. The same would apply to a device configured for implementing such a method.

[0110] The present invention also relates to a vehicle, for example an automobile or more generally an autonomous land-based motor vehicle, comprising the device 3 of [Fig.4].

Claims

Claims

1. Method for supplying an encryption key to a first and a second on-board computer of a vehicle by an off-board device, comprising the following steps: - reception (41), by the first computer, of a first signal emitted by the off-board device, said first signal carrying data representative of a request to launch a process of learning a first encryption key and carrying data defining the first encryption key; - launching (42) by the first computer of the process of learning the first encryption key; - transmission (43), by the first computer and intended for the second computer, of a second signal carrying data representative of a request to launch a process of learning a second encryption key and carrying data defining the second encryption key; - reception (44), by the second computer, of the second signal;and - launching (45), by the second computer, of the process of learning the second encryption key.;

2. Method according to claim 1, which further comprises a step of reception (46), by the first computer, of a third signal emitted periodically by the second computer, said third signal carrying data representative of a progress state of the process of learning the second encryption key launched by the second computer.

3. Method according to claim 2, which further comprises the following steps: - reception (47), by the first computer, of a fourth signal transmitted periodically by the remote device, said fourth signal carrying data representative of a request for progress status of the encryption key learning process; and - transmission (48), by the first computer, of a fifth signal to the remote device, said fifth signal carrying data representative of a progress status of the learning process of the first encryption key launched by the first computer and of the progress status of the learning process of the second encryption key carried by the fourth signal received.

4. Method according to one of the preceding claims, in which the first and second encryption keys are identical.

5. Method according to one of claims 1 to 3, in which the first and second encryption keys are different and which further comprises the following steps: - generation (49) of the second key by the first computer; - launching (50) by the first computer of the process of learning the second encryption key; - said fifth signal carrying data representative of a progress state of the process of learning the first and second encryption keys by the first computer and of the progress state of the process of learning the second encryption key by the second computer.

6. The method of claim 5, wherein the second encryption key is generated based on the first encryption key.

7. Device for supplying an encryption key to a first and a second on-board computer of a vehicle by an off-board device, the device comprising a memory associated with a processor configured for implementing the steps of the method according to one of claims 1 to 6.

8. Computer program comprising instructions for implementing the method according to any one of claims 1 to 6, when these instructions are executed by a processor.

9. A computer-readable recording medium on which is recorded a computer program comprising instructions for carrying out the steps of the method according to any one of claims 1 to 6.

10. A vehicle comprising a device according to claim 7.

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