FR3090721A1 - Vehicle unlocking control system and fingerprint learning method in a vehicle unlocking control system - Google Patents

Abstract

A vehicle unlocking control system, comprising: - a communication module (14) designed to establish a radio link with an electronic device (2) and to measure a footprint of the radio link established between the communication module ( 14) and the electronic device (2); - a processing unit (16) designed to detect a predetermined action on a member of the vehicle (20); - a storage unit (17) designed to store data representative of the fingerprint measured only when the predetermined action is detected by the processing unit (16). An associated fingerprint learning method is also described. Figure for the abstract: FIG. 1

Description

Description

Title of the invention: Vehicle unlocking control system and fingerprint learning method in a vehicle unlocking control system

The present invention relates generally to the field of remote unlocking of vehicles such as motor vehicles.

It relates more particularly to a vehicle unlocking control system and a fingerprint learning method in a vehicle unlocking control system.

We know the vehicle unlocking control systems, comprising a communication module designed to establish a radio link with an electronic device and to receive an unlocking instruction from the electronic device via the established link.

In order to combat certain attacks targeting such systems, it has been proposed, for example in the article Wi-Fi fingerprint-based approach to securing the connected vehicle against wireless attack (by H. Kwon, S. Lee, B. Chung in Computer Science & Information Technology 2016, pp. 211-217), to measure an imprint of the established radio link in order to verify that the electronic device requesting unlocking is indeed the one expected.

In this context, the present invention provides a vehicle unlocking control system, comprising:

- A communication module designed to establish a radio wave connection with an electronic device and to measure a footprint of the radio link established between the communication module and the electronic device;

- a processing unit designed to detect a predetermined action on an organ of the vehicle;

- a storage unit designed to store data representative of the measured fingerprint only in the event of detection of the predetermined action by the processing unit.

Thus, the storage of the fingerprint associated with the electronic device (fingerprint which will then be used to authorize the unlocking of the vehicle on instruction from this electronic device) is only possible when a predetermined action is performed on this member of the vehicle. This limits the storage of such a fingerprint to users who have access to the vehicle body (and who are therefore authorized users of this vehicle).

According to other optional features (and therefore not limiting):

- the member is a user interface embedded in the vehicle;

- the predetermined action is the entry of a predefined code on the user interface;

- the organ is a physical key of the vehicle;

- the storage unit is further designed to store data representative of the measured fingerprint only in the event of prior reception of a virtual key by the processing unit via the established link;

- the processing unit is designed to control unlocking only if the fingerprint measured by the communication module on receipt of an unlocking instruction via the established link corresponds to the fingerprint represented by the stored data;

- the unlocking instruction includes a virtual key;

- the processing unit is designed to control the unlocking only if the virtual key received corresponds to a reference virtual key stored within the processing unit.

The invention also provides a fingerprint learning method in a vehicle unlocking control system (this unlocking control system comprising a communication module and a storage unit); the process comprises the following stages:

- Detection, by a processing unit, of a predetermined action on an organ of the vehicle;

- establishment of a radio wave connection between the communication module and an electronic device;

- Measurement, by the communication module, of an imprint of the radio link established between the communication module and the electronic device;

- storage of data representative of the footprint measured in the storage unit, the implementation of the storage step at least being conditioned by the implementation of the detection step.

Such a method can further comprise the following steps:

- reception, by the processing unit and via the established link, of an unlocking instruction;

- upon receipt of the unlocking instruction, measurement of a new fingerprint of the link established by the communication module;

- Unlocking control by the processing unit only if the new measured fingerprint corresponds to the fingerprint represented by the stored data.

The electronic device is for example a smartphone.

Of course, the different characteristics, variants and embodiments of the invention can be associated with each other in various combinations as long as they are not incompatible or mutually exclusive of each other.

In addition, various other characteristics of the invention appear from the appended description made with reference to the drawings which illustrate non-limiting forms of embodiment of the invention and where:

[Fig.l] represents an example of context in which the invention can be implemented,

[Fig-2] is a flow diagram representing an example of a method for learning a fingerprint according to the invention, and

[Fig.3] is a flow diagram representing an example of a vehicle unlocking method using such a fingerprint.

Figure 1 shows an example of context in which the invention can be implemented.

It is desired here that an electronic device 2 (for example a smartphone or smart phone) can control the unlocking of a vehicle 10 equipped with an unlocking system 12 and a member 20 on which a user can act . Such a member 20 of the vehicle 10 is here a user interface (for example a touch screen). As a variant, the member 20 of the vehicle 10 could for example be a physical key of the vehicle 10.

In order to control the unlocking of the vehicle 10, the electronic device 2 stores a virtual key VK. This virtual key VK has for example been transmitted to the electronic device 2 during a prior step (for example by transmission, possibly in encrypted form, of an electronic message intended for the electronic device 2 and containing the virtual key VK).

The unlocking system 12 includes a communication module 14, a processing unit 16, a storage unit 17 and an unlocking actuator 18.

The processing unit 16 and the storage unit 17 are here functional units produced in practice by means of a microcontroller 15. This microcontroller comprises for example a processor and a memory; this memory stores in particular computer program instructions designed to implement the steps carried out (as indicated below) by the processing unit 16 and by the storage unit 17 when these instructions are executed by the processor.

The communication module 14 on board the vehicle 10 is designed to establish a wireless link (ie by radio waves) with the electronic device 2, for example a Bluetooth type communication (here precisely of BLE type for Bluetooth Low Energy ).

FIG. 2 shows an example of a method for learning a fingerprint.

This method can for example be triggered on command of a user who wishes to allow his electronic device 2 (which stores the virtual key VK) to control the unlocking of the vehicle 10 securely vis-à-vis relay attacks , as explained below with reference to FIG. 3. This command to trigger the process of FIG. 2 is for example carried out via the user interface 20.

Once triggered on user command, the process begins in step E2 by establishing a wireless link (i.e. by radio waves) between the communication module 14 and the electronic device 2.

Once this link has been established, the communication module 14 can measure in step E4 an imprint of the radio link established between the communication module 14 and the electronic device 2. The technique for measuring the imprint used is by example as described in the article Wireless Device Authentication Techniques Using Physical-Layer Device Fingerprint, by Peng Hao, Electronic Thesis and Dissertation Repository, 3440. The fingerprint is for example represented by a series of bytes (having a size typically included between 1 kb and 5 kb).

The method continues in step E6 in which the processing unit determines whether a predetermined action is performed on the member 20 of the vehicle 10 (here the user interface 20 on board the vehicle 10), for example within a predetermined period of time (typically between 10 s and 30 s).

In practice, this predetermined action is for example the entry of a predefined code on the user interface 20 (such a predefined code can be communicated to the user when purchasing the vehicle 10).

As a variant, the member 20 could for example be a physical key of the vehicle. The predetermined action on the member 20 of the vehicle 10 can in this case be the pressing of a key of the physical key.

If the processing unit 16 detects the predetermined action on the member 20, the fingerprint learning process continues at step E9 described below.

In the absence of detection of the predetermined action on the member 20 (here in the aforementioned period of time), the method continues at step E8 where the learning process is ended without memorization of the footprint measured in step E4.

In the example described here, when the processing unit 16 detects the predetermined action on the member 20, the communication module 14 (on command of the processing unit 16) transmits in step E9 a request R intended for the electronic device 2 in order to verify that the electronic device 2 holds the virtual key VK.

The electronic device 2 receives this request R and sends in response the virtual key VK to the unlocking system 12 of the vehicle 10 (step E10).

The communication module 14 receives the virtual key VK in step E12 and transmits the virtual key VK to the processing unit 16.

The processing unit 16 can thus determine in step E14 whether the virtual key VK received corresponds to an authorized virtual key (that is to say in practice determine whether the virtual key VK received is equal to one stored virtual reference key, possibly in association with an identifier of the electronic device 2, within the processing unit 16).

If not in step E14, the process continues in step E16 where the learning process is ended without memorizing the fingerprint measured in step E4.

On the other hand, if the processing unit 16 determines in step E14 that the virtual key VK received corresponds to an authorized virtual key, the method continues in step El8 at which data representative of the fingerprint measured are stored by the storage unit 17. This data representative of the measured footprint can then be used as described below with reference to FIG. 3.

The step of memorizing the measured footprint is therefore conditioned by the detection of the predetermined action on the member 20 of the vehicle 10 (see step E6 above) and, here, by the reception of the key VK from the electronic device 2 (see step E14). It is thus ensured that only an authorized user can memorize the characteristic fingerprint of the connection established between his electronic device 2 and the communication module 14.

FIG. 3 shows an example of a method for unlocking the vehicle 10 using such a fingerprint. Such a method can therefore be implemented after that of FIG. 2.

This process begins in step E52 by establishing a radio wave connection between the communication module 14 of the unlocking system 12 and the electronic device 2. As indicated above, this connection is for example of Bluetooth type, possibly BLE type.

The electronic device 2 transmits in step E54, to the unlocking system 12, a unlocking instruction I to which is attached the virtual key VK (this virtual key VK being as already indicated stored in the device electronic 2). This transmission is for example triggered on instruction from the user of the electronic device 2, possibly by selection of a dedicated element on a user interface of the electronic device 2. This transmission can also be carried out via the radio link established in step E52.

The communication module 14 thus receives this instruction I and the virtual key VK in step E56, here via the radio link established in step E52. The communication module 14 can then transmit this instruction I and the virtual key VK to the processing unit 16.

The communication module 14 of the unlocking system 12 can also measure in step E58 the footprint of the radio link established between the communication module 14 and the electronic device 2. The technique of measuring the footprint is identical to that mentioned above in step E4.

The processing unit 16 also reads in step E60 the data representative of the fingerprint stored by the storage unit 17 (during step E18 of FIG. 2 described above).

The processing unit 16 can thus proceed to step E62 by comparing the footprint measured in step E58 and the footprint represented by these representative data.

If the measured footprint corresponds to the footprint represented by the stored representative data, the electronic device 2 is indeed the one whose footprint was measured during step E4: it is therefore a electronic device 2 which is authorized to control the unlocking and the process can therefore continue normally in step E66.

On the other hand, if the measured footprint does not correspond to the footprint represented by the representative stored data (case of abnormal operation which does not correspond to the context of FIG. 1), this means that the electronic device in Communication with the communication module 14 is not the authorized electronic device, but for example the electronic device of an attacker who is trying to fraudulently unlock the vehicle 10 (for example by means of a relay attack). The processing unit 16 proceeds in this case to step E64, where the processing unit 16 terminates the process without controlling the unlocking of the vehicle.

In the normal operation where the method continues in step E66 as indicated above, the processing unit 16 determines whether the virtual key VK received in step E56 corresponds to an authorized virtual key ( that is to say in practice to a virtual reference key stored in the processing unit 16).

If the virtual key received VK corresponds (in practice: is equal) to an authorized virtual key (ie here stored in the processing unit 16), the processing unit 16 controls in step E70 the unlocking of the vehicle 10 by sending an unlock command to the unlocking actuator 18.

If on the contrary the virtual key received VK does not correspond to an authorized virtual key (ie here stored in the processing unit 16), the processing module 16 proceeds to step E68 where the process is terminated without unlocking the vehicle 10.

The method which has just been described thus makes it possible to condition the unlocking of the vehicle 10 to the measurement of a print of the radio link with the electronic device 2 which corresponds to a print previously stored (by means of representative data) , which indicates that the electronic device 2 is authorized to control the unlocking. This especially prevents relay attacks.

Of course, various other modifications can be made to the invention in the context of the appended claims.

Claims (1)

Claims [Claim 1] A vehicle unlocking control system, comprising: - a communication module (14) designed to establish a radio link with an electronic device (2) and to measure a footprint of the radio link established between the communication module (14 ) and the electronic device (2); - a processing unit (16) designed to detect a predetermined action on a member of the vehicle (20); - a storage unit (17) designed to store data representative of the measured fingerprint only in the event of detection of the predetermined action by the processing unit (16). [Claim 2] The system of claim 1, wherein the member is a user interface (20) embedded in the vehicle (10). [Claim 3] The system of claim 2, wherein the predetermined action is the entry of a predefined code on the user interface (20). [Claim 4] The system of claim 1, wherein the member is a physical key to the vehicle. [Claim 5] System according to one of claims 1 to 4, in which the storage unit (17) is further designed to store the data representative of the measured fingerprint only in the event of prior reception of a virtual key (VK) by the processing unit (16) via the established link. [Claim 6] System according to one of claims 1 to 5, in which the processing unit (16) is designed to control unlocking only if the fingerprint measured by the communication module (14) on receipt of an instruction (I) for unlocking via the established link corresponds to the fingerprint represented by the stored data. [Claim 7] System according to claim 6, in which the unlocking instruction (I) comprises a virtual key (VK) and in which the processing unit (16) is designed to control unlocking only if the received virtual key (VK) corresponds to a virtual reference key stored in the processing unit (16). [Claim 8] Method for learning fingerprints in a vehicle unlocking control system, the unlocking control system comprising a communication module (14) and a storage unit (17), the method comprising the following steps: - detection (E6), by a processing unit (16), of a predefined action - terminated on a member (20) of the vehicle (10); - establishment (E2) of a radio wave connection between the communication module (14) and an electronic device (2); - measurement (E4), by the communication module (14), of an imprint of the radio link established between the communication module (14) and the electronic device (2); - storage (El8) of data representative of the footprint measured in the storage unit (17), in which the implementation of the memorization step (El8) at least is conditioned by the implementation of the detection step (E6). [Claim 9] Method according to claim 8, comprising the following steps: - reception (E56), by the processing unit (16) and via the established link, of an unlocking instruction (I); - upon receipt of the unlocking instruction (I), measurement (E58) of a new fingerprint of the link established by the communication module (14); - control (E66, E70) of unlocking by the processing unit (16) only if the new measured fingerprint corresponds to the fingerprint represented by the stored data. [Claim 10] Method according to claim 8 or 9, in which the electronic device (2) is a smartphone. 1/2