JP2013157898A - Portable device registration system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high security portable device registration system re-registration of which is allowed before shipping.SOLUTION: The portable device registration system shares an encryption key with a vehicle 1, and registers an electronic key 2 required for encryption communication using the encryption key in the immobilizer ECU 6 of the vehicle 1. The immobilizer ECU 6 generates an encryption key from an SEED code included in an ID code signal transmitted from the electronic key 2 by using a key generation logic, and registers the encryption key. The electronic key 2 includes a counter for counting the number of transmission times of the ID code signal. The electronic key 2 is inspected whether or not the ID can be collated between the immobilizer ECU 6 before shipping. The electronic key 2 transmits the ID code signal a specified number of times for inspection. When the count reaches a number of times of delete which is set to a specified number of times, the electronic key 2 deletes the SEED code.

Description

  The present invention relates to a portable device registration system for registering a portable device with a control device to be communicated.

  2. Description of the Related Art Conventionally, a portable device system that performs encrypted communication between a portable device possessed by a vehicle user and the vehicle and performs locking / unlocking of a door, starting / stopping of an engine, etc. based on the establishment of authentication is known. ing. And in such a portable machine system, in order to maintain security, it is necessary to protect communication between a portable machine and a vehicle. For this reason, in the portable device system, encryption communication is performed between the portable device and the vehicle (see, for example, Patent Document 1). In encrypted communication, since the communication content is encrypted, it is excellent in confidentiality.

  A common key encryption method is adopted as the encryption method of the encryption communication. In the common key cryptosystem, the same encryption key is used for encryption and decryption. For this reason, it is necessary to have the same encryption key in both the portable device and the vehicle. The registration of the encryption key to the portable device and the vehicle is performed in the process of registering the portable device to the vehicle control device. The control device authenticates with the portable device by collating the identification information wirelessly transmitted from the portable device with the identification information stored in itself.

JP 2009-302848 A

  By the way, in a portable device registration system for registering a portable device with a control device, if there is no association between the control device and the portable device, any portable device can be registered with the control device, and other than the user May be registered in the control device. Therefore, the inventor of the present application considered shipping in a state where the vehicle ID (identification information unique to the vehicle) of the vehicle to be registered is stored in advance in the control device and the portable device. However, there is a possibility that identification information unique to the vehicle is read from the shipped portable device, and the same portable device that is normally shipped may be illegally copied. In this case, the control device determines that the duplicated portable device is a portable device corresponding to itself.

  Therefore, the inventor of the present application is examining an encryption key registration method for preventing the portable device from being duplicated. For example, a code required for generating the encryption key is stored in the portable device, and a logic required for generating the encryption key from the code is stored in advance in the control device. Then, when registering the encryption key, a code is transmitted from the portable device, and the control device that has received the code generates an encryption key using the logic from the code and registers it. After transmitting the code, the portable device deletes the code. Thus, the control device can register the encryption key only from the code. That is, the portable device from which the code is erased is not registered in the control device. Therefore, even if the portable device from which the code is erased is copied, it is difficult to illegally use the vehicle using the portable device.

  On the other hand, the portable device from which the code has been deleted cannot be registered in the control device at that time. Therefore, when it is desired to re-register a portable device from which the code is erased with another control device for some reason, even if it is before shipment, the portable device cannot be registered with another control device. .

  The present invention has been made in view of such circumstances, and an object thereof is to provide a portable device registration system that has high security and allows re-registration before shipment.

  In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that the same encryption key is held with a communication target and encrypted communication is performed with the communication target control device using the encryption key. In the portable device registration system for registering a portable device to be performed in the control device, the control device stores key generation logic for generating an encryption key from identification information unique to the communication target and a key generation code fetched from the outside. The portable device stores an encryption key generation code unique to the portable device used when generating the encryption key, and the encryption key generated using the key generation logic, The control device writes the identification information to the registered portable device through wireless communication with the portable device as the registration processing of the portable device, and stores the encryption key generation code stored in the portable device. The encryption key is generated from the key generation code using the key generation logic stored therein, and the generated encryption key is stored. The portable device includes the control device A counter that counts the number of times encrypted communication is performed or the time from when encrypted communication is started, and the portable device is shipped in advance from the registration of the identification information to before shipment The encrypted communication is performed with the communication target at the previous maximum communication count or less, and the value of the counter reaches the deletion count set to be equal to or higher than the maximum pre-shipment communication count, or the identification information The gist is to delete the encryption key generation code when a deletion time set to be longer than the longest pre-shipment time that may be taken from the completion of registration to shipping is reached.

  Usually, many products are tested for proper operation before shipping. Only products that pass the inspection are shipped. The portable device and the communication target control apparatus actually perform encrypted communication, and determine whether or not the encrypted communication is suitably performed. The number of encrypted communications (maximum number of communications before shipment) to be performed for inspection, even if there is an increase due to irregularity, etc., between the time when registration between the portable device and the control device is made and before shipment. It is decided in advance. Similarly, even if an increase due to irregularity or the like is included, the time from the start of encrypted communication for inspection to the shipment (the longest pre-shipment time) is also determined in advance. According to this configuration, the portable device counts the number of times of encrypted communication or the time from the start of communication through the counter. Then, the encryption key generation code is deleted when the counted number reaches the number of deletions set to be equal to or greater than the maximum number of communications before shipment, or when the deletion time set to be equal to or more than the maximum time before shipment is reached. That is, the encryption key generation code of the portable device is not deleted before shipment. Thereby, before shipping, the portable device can be re-registered with another control device. In addition, since the encryption key generation code is deleted after shipment, it is difficult to illegally duplicate the portable device from information stored in the portable device even if the encryption key generation logic is leaked.

The invention according to claim 2 is summarized in that, in the portable device registration system according to claim 1, the deletion count is the maximum communication count before shipment.
According to this configuration, since the number of deletions and the maximum number of communication before shipment are the same, there is a high possibility that the portable device at the time of shipment is in a state where the key generation code has been deleted. For this reason, even if the encryption key generation logic leaks after shipment, it is difficult to illegally duplicate the portable device from the information stored in the portable device.

The gist of the invention described in claim 3 is the portable device registration system according to claim 1, wherein the deletion time is the longest time before shipment.
According to this configuration, since the deletion time and the longest pre-shipment time are the same, the portable device at the time of shipment is highly likely to be in a state where the key generation code has been deleted. For this reason, even if the encryption key generation logic is leaked, it is difficult to illegally duplicate the portable device from the information stored in the portable device.

  According to a fourth aspect of the present invention, in the portable device registration system according to any one of the first to third aspects, the identification information stored in the control device before shipment and an additional registration encryption key Alternatively, a portable device and a control device, which are provided for storing a database that stores an associated key for generating an additional registration key in association with each other, include the identification information stored in the database and the additional registration. And the encryption key generated from the encryption key generation code for additional registration.

  According to this configuration, the replenishing portable device and the control device store the identification information and the encryption key at the time of manufacture. For this reason, encrypted communication can be performed between the portable device and the control device without requiring a special registration operation.

  The gist of a fifth aspect of the present invention is the portable device registration system according to any one of the first to fourth aspects, wherein the control device deletes the key generation logic after use.

  According to this configuration, since the key generation logic is deleted after registering the portable device, it is possible to prevent another portable device from being registered in the control device.

  According to the present invention, it is possible to provide a portable device registration system that has high security and allows re-registration before shipment.

The block diagram which shows schematic structure of an electronic key registration system. The figure which shows manufacture of an electronic key registration system. The figure which shows registration of an electronic key registration system. The sequence chart which shows the registration work of an electronic key registration system. The figure which shows manufacture of the additional key of an electronic key registration system. The figure which shows manufacture of exchange ECU of an electronic key registration system. The sequence chart which shows the confirmation work of an electronic key registration system.

Hereinafter, an embodiment in which an electronic key registration system according to the present invention is embodied in a vehicle will be described with reference to FIGS.
As shown in FIG. 1, the vehicle 1 is provided with an immobilizer system 3 that executes ID collation with the electronic key 2 by, for example, short-range wireless communication (wireless communication with a communication distance of about several centimeters). The electronic key 2 is provided with an ID tag, so-called transponder 4. The immobilizer system 3 is a system that performs ID verification based on an ID code signal transmitted from the transponder 4 when the transponder 4 is activated by a driving radio wave transmitted from the coil antenna 5 of the vehicle 1. Note that the vehicle 1 corresponds to a communication target. The immobilizer system 3 functions as an electronic key system.

  The vehicle 1 is provided with an immobilizer ECU 6 as a control unit of the immobilizer system 3. An engine ECU 12 that controls the operation of the engine 11 is connected to the immobilizer ECU 6 via an in-vehicle LAN 13. In the memory 67 of the immobilizer ECU 6, the ID code of the electronic key 2 that forms a pair with the vehicle 1 is registered. The immobilizer ECU 6 is connected to a coil antenna 5 that transmits and receives radio waves in an LF (Low Frequency) band and an HF (High Frequency) band. The coil antenna 5 employs a magnetic field antenna that transmits radio waves using a magnetic field component, and is provided in a key cylinder. The immobilizer ECU 6 corresponds to a control device.

  The transponder 4 of the electronic key 2 is provided with a control unit 41 that controls the communication operation. An ID code (transponder code) unique to the electronic key 2 is registered in the memory 42 of the control unit 41. The transponder 4 is provided with a transmission / reception antenna 21 for transmitting and receiving radio waves in the LF band and the HF band.

  When the immobilizer ECU 6 detects that the electronic key 2 is inserted into the key cylinder, the immobilizer ECU 6 intermittently transmits drive radio waves from the coil antenna 5. When the boarded user starts the engine 11, the electronic key 2 is inserted into the key cylinder to perform a turning operation. At this time, when the transponder 4 receives the driving radio wave transmitted from the coil antenna 5 by the transmission / reception antenna 21, the transponder 4 starts up using the driving radio wave as a power source. When the transponder 4 is switched to the activated state, the transponder 4 transmits an ID code signal including an ID code registered in the transponder 4 from the transmission / reception antenna 21. When the immobilizer ECU 6 receives the ID code signal transmitted from the transponder 4 by the coil antenna 5, the immobilizer ECU 6 executes ID verification (immobilizer verification) using the ID code included in the ID code signal. The immobilizer ECU 6 stores the ID verification result in the memory 67.

  An ignition switch (IGSW) 14 for detecting the rotational position of the electronic key 2 is provided in the key cylinder. When the ignition switch 14 is operated to the engine start position, the engine ECU 12 checks with the immobilizer ECU 6 whether or not ID verification is established. The engine ECU 12 acquires the result of the ID collation from the immobilizer ECU 6, and when the result indicates that the collation is established, the engine ECU 12 starts the ignition control and the fuel injection control to the engine 11 and starts the engine 11.

  The immobilizer ECU 6 executes challenge response authentication in addition to code verification for confirming the ID code of the electronic key 2. In challenge response authentication, for example, the vehicle 1 transmits a challenge code as a random number code to the electronic key 2 to calculate the response, and the response code calculated by the vehicle 1 itself matches the response code received from the electronic key 2. It is authentication by NO. For the authentication between the immobilizer ECU 6 and the transponder 4 in this example, a common key encryption method using a common encryption key is employed. The electronic key 2 and the immobilizer ECU 6 calculate a response code from the challenge code using the encryption keys registered respectively.

  The memory 42 of the transponder 4 stores a vehicle ID (VID), which is identification information unique to the vehicle 1, a SEED code (SC) used when generating the encryption key K, and an encryption key K used for authentication. Has been.

  The memory 67 of the immobilizer ECU 6 stores a vehicle ID (VID) that is identification information unique to the vehicle 1, an encryption key K used for authentication, and a key generation logic f used when generating the encryption key K. ing.

  Further, the immobilizer system 3 includes an electronic key registration system 7 that registers the electronic key 2 in the immobilizer ECU 6. The electronic key registration system 7 is a system that performs wireless communication between the electronic key 2 and the immobilizer ECU 6 and registers information unique to each other. The electronic key registration system 7 includes a database 9 that stores a plurality of encryption keys associated with one vehicle ID. The database 9 is provided in a parts factory that manufactures the electronic key 2 and the immobilizer ECU 6. As shown in FIG. 2, the database 9 stores an encryption key (K-2) corresponding to a vehicle ID (VID-A) unique to the vehicle 1. When the immobilizer ECU 6 and the electronic key 2 are manufactured, data stored in the database 9 is stored in the memories 42 and 67, respectively.

  As shown in FIG. 1, the electronic key registration system 7 includes a registration tool 8 for registering the electronic key 2 in the immobilizer ECU 6. The registration tool 8 is used by being connected to the vehicle 1. The registration tool 8 switches the operation mode of the immobilizer ECU 6 between the normal mode and the registration mode. The immobilizer ECU 6 in the registration mode wirelessly communicates with the electronic key 2 to register its own information (vehicle ID (VID-A)) in the electronic key 2 and also to the electronic key 2. Information (encryption key (K-2)) is registered. The registration tool 8 includes a control unit 81 that controls the registration tool 8, an operation unit 82 that detects a registration operation by the user, and a display unit 83 that displays the registration operation. When the registration tool 8 is operated by the user and set to the registration mode, the registration tool 8 outputs a registration signal indicating that the operation mode of the immobilizer ECU 6 is changed to the registration mode to the vehicle 1. In addition, when receiving the database update signal from the immobilizer ECU 6, the registration tool 8 updates the information in the database 9 via a network (not shown).

  The immobilizer ECU 6 is provided with a mode switching unit 61 that switches operation modes. When a registration signal is input from the registration tool 8, the mode switching unit 61 switches the operation mode from the normal mode to the registration mode. The mode switching unit 61 switches the operation mode to the normal mode when the connection between the immobilizer ECU 6 and the registration tool 8 is released after switching to the registration mode. The immobilizer ECU 6 in the normal mode performs normal authentication, that is, ID verification with the electronic key 2.

  The immobilizer ECU 6 is provided with a vehicle ID transmission unit 62 that transmits a vehicle ID to the electronic key 2 to be registered. When the operation mode of the immobilizer ECU 6 is switched to the registration mode, the vehicle ID transmission unit 62 transmits a vehicle ID signal including the vehicle ID stored in the memory 67 from the coil antenna 5 to the electronic key 2.

  Further, the immobilizer ECU 6 is provided with a SEED reading unit 64 that reads a SEED code in order to generate the encryption key K stored in the electronic key 2. The immobilizer ECU 6 transmits a SEED request signal for requesting a SEED code from the coil antenna 5. When the electronic key 2 receives the SEED request signal, the electronic key 2 generates a SEED signal including a SEED code, and transmits the generated signal. The SEED reading unit 64 extracts the SEED code from the SEED signal received via the coil antenna 5.

  The immobilizer ECU 6 is provided with an encryption key generation unit 65 that generates an encryption key K. The encryption key generation unit 65 generates the encryption key K from the SEED code acquired by the SEED reading unit 64 using the key generation logic f stored in the memory 67.

  The control unit 41 of the electronic key 2 is provided with a counter 43 that counts the number of transmissions of an ID code signal for ID verification. An operation check is performed between the immobilizer ECU 6 and the electronic key 2 to check whether the ID verification using the registered encryption key can be performed normally. Here, it is assumed that the operation is confirmed 20 times. When the control unit 41 confirms that the number of times counted by the counter 43 has reached the number of deletions, here, 20 times, which is the number of operation confirmations, the control unit 41 deletes the SEED code stored in the memory 42.

Next, the registration operation of the electronic key 2 to the immobilizer ECU 6 will be described with reference to FIGS.
The vehicle 1 is composed of various parts. For this reason, after each part is manufactured in a parts factory, it is collected in an assembly factory, and is assembled | attached to the vehicle 1 there. That is, the immobilizer ECU 6 and the electronic key 2 are each manufactured at the parts factory, then collected at the assembly factory, and assembled to the vehicle through the assembly line. And the registration operation | work of the electronic key 2 with respect to immobilizer ECU6 is performed.

  First, the manufacturing work in the parts factory before the registration work will be described. As shown in FIG. 2, a key generation logic f is stored in the memory 67 of the immobilizer ECU 6 manufactured for initial registration. Further, in the memory 67, the vehicle ID (VID-A) of the vehicle 1 to be mounted and the encryption key (K-2) of the electronic key 2 to be additionally registered are stored from the database 9. On the other hand, the SEED code (SC-1) is stored in the memory 42 of the electronic key 2 manufactured for initial registration. The memory 42 also stores an encryption key (K-1) generated from the SEED code (SC-1) using the key generation logic f.

  Next, the registration operation of the electronic key 2 in the assembly factory will be described. As shown in FIG. 3, in the electronic key registration system 7 of this example, the immobilizer ECU 6 transmits a vehicle ID signal including a vehicle ID (VID-A). When receiving the ID code signal from the immobilizer ECU 6, the electronic key 2 registers the ID code included in this signal. The electronic key 2 transmits a SEED code signal including a SEED code (SC-1). The immobilizer ECU 6 temporarily stores the SEED code included in the SEED code signal in the memory 67, and generates an encryption key (K-1) from the SEED code using the key generation logic f, and stores this in the memory 67. Remember. The SEED code is deleted after updating the database 9 described later.

  Here, the registration process procedure of the electronic key 2 will be described in detail according to the sequence chart shown in FIG. As shown in FIG. 4, when the registration tool 8 is operated by the user and set to the registration mode, the registration tool 8 outputs a registration signal to the immobilizer ECU 6 (step S1). When receiving the registration signal, the immobilizer ECU 6 switches the operation mode to the registration mode (step S2).

  Then, the immobilizer ECU 6 transmits a vehicle ID signal including the vehicle ID (VID-A) stored in the memory 67 from the coil antenna 5 to the electronic key 2 (step S3).

  When receiving the vehicle ID signal, the electronic key 2 stores the vehicle ID (VID-A) included in the vehicle ID signal in the memory 42 (step S4). Then, the electronic key 2 locks the writing of the vehicle ID (step S5). That is, the electronic key 2 prohibits overwriting of the vehicle ID in the memory 42. Thereby, the electronic key 2 prevents the vehicle ID in the memory 42 from being rewritten.

  Immobilizer ECU6 transmits the SEED request | requirement signal which requests | requires transmission of a SEED code from the coil antenna 5 following transmission of vehicle ID of step S3 (step S6).

  When receiving the SEED request signal, the electronic key 2 transmits a SEED signal including the SEED code (SC-1) stored in the memory 42 as a response thereto (step S7).

  When receiving the SEED signal, the immobilizer ECU 6 generates an encryption key (K-1) using the key generation logic f from the SEED code (SC-1) included in the signal (step S8). That is, the immobilizer ECU 6 does not directly acquire the encryption key (K-1) from the electronic key 2, but generates the encryption key (K-1) by acquiring the SEED code (SC-1). The SEED code (SC-1) is temporarily stored in the memory 67.

  Subsequently, the immobilizer ECU 6 stores the generated encryption key (K-1) in the memory 67 (step S9). The immobilizer ECU 6 can perform ID collation with the electronic key 2 by using the registered encryption key (K-1).

  Subsequently, the immobilizer ECU 6 outputs a database update signal to the registration tool 8 in order to update the information in the database 9 (step S10). The database update signal includes the SEED code (SC-1) used for generating the encryption key (K-1) associated with its own vehicle ID (VID-K). The registration tool 8 that has received the database update signal transmits the SEED code (SC-1) to the database 9 in a state associated with the vehicle ID (VID-K) via a network (not shown), and stores it in the database 9. (Update of database 9) (step S11). Thereby, as shown in FIG. 3, the SEED code (SC-1) is stored in the database 9 as information relating to the encryption key (K-1) corresponding to the vehicle ID (VID-A). Accordingly, the vehicle ID (VID-A) and the encryption key (K-1) stored in the memory 67 of the immobilizer ECU 6 and the vehicle ID (VID-A) and the encryption key (K-1) stored in the memory 42 of the electronic key 2 are stored. Since K-1) matches, both can be collated with ID. The immobilizer ECU 6 deletes the SEED code from the memory 67 after updating the database 9.

  Next, the manufacturing operation of the electronic key 2 additionally registered in the immobilizer ECU 6 after vehicle shipment will be described. As shown in FIG. 5, in the parts factory, in the memory 42 of the electronic key 2 for additional registration, the vehicle ID (VID-A) of the mounted vehicle 1 and the vehicle ID (V-ID) are added according to the order. ) Corresponding to the additional registration encryption key (K-2). The stored vehicle ID (V-ID) and encryption key (K-2) are stored in the database 9. That is, the additionally registered electronic key 2 is manufactured in a state corresponding to the immobilizer ECU 6. For this reason, it is possible to collate the ID with the immobilizer ECU 6 without requiring a special registration work. The additionally registered electronic key 2 is manufactured in a state where the SEED code is not stored in the memory 42. That is, the electronic key 2 for additional registration is shipped in a state where no SEED code is stored in the memory 42.

  Next, the manufacturing operation of the replacement immobilizer ECU 6 will be described. As shown in FIG. 6, in the parts factory, the memory 67 of the replacement immobilizer ECU 6 stores the vehicle ID (VID-A) of the vehicle 1 to be mounted and the vehicle ID (V-ID) according to the order. And the encryption key (K-2) corresponding to. The stored vehicle ID (V-ID) and encryption key (K-2) are stored in the database 9. That is, since the replacement immobilizer ECU 6 is manufactured in a state corresponding to the immobilizer ECU 6 before replacement, it is possible to collate the ID with the electronic key 2 without requiring special registration work.

Next, the confirmation work performed after the registration work will be described.
Even after the registration of the electronic key 2 to the immobilizer ECU 6, there are a plurality of work steps before shipping, such as assembling various parts and devices to the vehicle 1 on the assembly line. Some parts and devices to be assembled, such as a wiper device, need to be checked for proper operation after being assembled. When such components and devices are assembled, ID verification is performed between the immobilizer ECU 6 and the electronic key 2, the engine 11 is driven, and a check operation (operation check) is performed as to whether or not the device 11 operates properly. Here, when it operates suitably, it progresses to the next work process, and when it does not operate suitably, it reassembles etc. and confirms operation again. For this reason, the number of times of operation confirmation when the assembled parts and devices do not operate favorably is larger than the number of normal operation confirmations (for example, 15) at which all the assembled components and devices operate appropriately. There is a limit on the number of operation confirmations after one assembly operation. For this reason, the maximum number (20 in this case) of operation confirmation performed before shipment in one vehicle 1 is determined. Since it is necessary to perform ID collation between the immobilizer ECU 6 and the electronic key 2 for the operation confirmation, the number of ID collation matches the number of operation confirmations. Here, the case where the number of times of the operation confirmation is the largest 20 (maximum number of communication before shipment) will be described with reference to the sequence chart of FIG.

  As shown in FIG. 7, when one work process requiring the confirmation work is completed, the IGSW 14 is turned on, and the immobilizer ECU 6 transmits a drive radio wave from the coil antenna 5 (step S21). The transponder 4 of the electronic key 2 that has received the driving radio wave obtains the activation power from the radio wave and consumes the activation power to transmit the ID code signal (step S22). Thereafter, the counter 43 of the electronic key 2 increments (increases) the value by 1 (step S23).

  After receiving the ID code signal, the immobilizer ECU 6 starts the engine 11 if the ID code included in the ID code signal is correct (step S24). When the engine 11 is started, it is confirmed whether or not the assembled parts and devices operate suitably. The IGSW 14 is turned off regardless of whether or not the assembled component or device operates favorably, and the immobilizer ECU 6 stops the engine 11 (step S25).

  When the series of confirmation work is completed, if the assembled part or device does not operate properly, the confirmation work is performed again by reassembling the part. When the assembled part or device operates suitably, the vehicle 1 proceeds to a work process for assembling the next part. Then, after a work process that requires confirmation work, a series of confirmation work is performed. In this example, this confirmation operation is performed 20 times. That is, in the 20th confirmation operation, the counter 43 counts 20 (step S23-20). When the counter 43 counts 20 times, the control unit 41 of the electronic key 2 deletes the SEED code stored in the memory 42 (step S26). That is, the SEED code stored in the memory 42 is deleted when the operation is confirmed. Thereby, the electronic key 2 in which the SEED code is stored is not shipped.

As described above, according to the embodiment described above, the following effects can be obtained.
(1) The electronic key 2 is provided with a counter 43 that counts the number of transmissions of the ID code signal when the ID verification with the immobilizer ECU 6 is performed. The electronic key 2 has the SEED code stored in the memory 42 when the number of transmissions of the ID code signal counted by the counter 43 reaches the number of deletions (here, the maximum number of communication before shipping is 20). Was deleted.

  After a registration operation of the electronic key 2 to the immobilizer ECU 6, ID verification is performed between the immobilizer ECU 6 and the electronic key 2 every time one operation step requiring a confirmation operation is performed before shipping. The engine 11 is driven, and a check operation (operation check) is performed as to whether or not the assembled one operates properly. For this reason, at least the number of work processes (15 in this case) that require confirmation work, confirmation work, that is, ID verification is performed 15 times between the immobilizer ECU 6 and the electronic key 2. In addition, there is a limit on the number of operation confirmations after one assembly operation. For this reason, the maximum number of operation confirmations performed before shipment in one vehicle 1, that is, the maximum number of communications before shipment (here, 20) is determined. Here, when the counter 43 counts 20, which is the maximum number of communications before shipment, the electronic key 2 deletes the SEED code. In other words, the SEED code is not deleted before the final confirmation work. For this reason, when ID collation cannot be suitably performed between the electronic key 2 and the immobilizer ECU 6 before the final confirmation work, the electronic key 2 can be registered in another immobilizer ECU.

  (2) The shipped electronic key 2 finally deletes the SEED code. The ID verification between the electronic key 2 and the immobilizer ECU 6 requires an encryption key shared by both, and this encryption key is generated from the SEED code using the key generation logic f. For this reason, it becomes difficult for a third party to duplicate the electronic key 2 corresponding to the shipped immobilizer ECU 6.

(3) The electronic key 2 eventually deletes the SEED code by itself. For this reason, a deletion tool for deleting the SEED code is not required.
(4) The encryption key registered in the immobilizer ECU 6 is stored in the database 9 in a state associated with the vehicle ID code. The electronic key 2 for additional registration and the memory of the replacement immobilizer ECU 6 store the vehicle ID code stored in the database 9 and the corresponding encryption key. For this reason, ID verification can be performed between the immobilizer ECU 6 and the electronic key 2 without requiring a special registration operation.

  (5) The electronic key 2 for additional registration is manufactured with no SEED code stored in its memory. That is, even when shipped, the electronic key 2 does not have a SEED code. For this reason, it becomes difficult for a third party to duplicate the electronic key 2 corresponding to the shipped immobilizer ECU 6.

In addition, the said embodiment can be implemented with the following forms which changed this suitably.
In the above embodiment, the electronic key 2 is configured to delete the SEED code stored in the memory 42 when the counter 43 counts the transmission of the ID code signal 20 times. Can be changed. Note that the number of deletions is set to be equal to or greater than the number of operation confirmations (maximum number of communication before shipment) from the viewpoint of registering the electronic key 2 that cannot be suitably collated with the immobilizer ECU 6 in another immobilizer ECU. Even with this configuration, the electronic key 2 deletes the SEED code when the counter 43 counts the number of times of deletion, so that it is difficult to copy the electronic key 2 thereafter.

  In the above embodiment, the immobilizer ECU 6 may delete the key generation logic f itself after the registration work. In this way, it is possible to prevent another electronic key from being registered in the immobilizer ECU 6. Further, it is possible to prevent the key generation logic f itself from leaking outside. Even if the key generation logic f is not deleted, it is possible to prevent another electronic key from being registered in the immobilizer ECU 6 if the use is prohibited after the registration work.

  In the above embodiment, the counter 43 counts the number of transmissions of the ID code signal, but may count the time since the transmission of the ID code signal is started. In order to confirm the operation, the electronic key 2 transmits a first ID code signal to the vehicle equipped with the immobilizer ECU 6 that receives the ID code signal before shipment. take time. Using this, the electronic key 2 deletes the SEED code when the counted time reaches a deletion time set to be equal to or longer than the longest pre-shipment time. Even in this case, the SEED code can be prevented from leaking outside.

  In the above embodiment, the SEED code (SC-1) is stored in the database 9 as information on the encryption key (K-1) registered in the immobilizer ECU 6 after the registration work, but the encryption key (K-1) itself is stored in the database 9. You may save it. In this way, when the encryption key K is stored in the replacement immobilizer ECU 6 from the database 9, the calculation by the key generation logic f can be omitted.

  In the above embodiment, the present invention is applied to the type of immobilizer system 3 in which the electronic key 2 is inserted into the key cylinder. However, when the electronic key enters the communication area created by the radio wave transmitted from the vehicle 1, The present invention may be applied to an electronic key system of a type in which communication is performed.

  In the above embodiment, the present invention is applied to the immobilizer system 3 in which the electronic key 2 activated by receiving the driving radio wave from the vehicle 1 transmits a radio signal, but by operating a switch provided in the electronic key 2 The present invention may be applied to a so-called wireless system that transmits a radio signal toward the vehicle 1.

  In the above embodiment, the present invention is applied to the electronic key system of the vehicle 1, but the present invention may be applied to an electronic key system of a building such as a house.

DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Electronic key, 3 ... Immobilizer system, 4 ... Transponder, 5 ... Coil antenna, 6 ... Immobilizer ECU, 7 ... Electronic key registration system, 8 ... Registration tool, 9 ... Database, 11 ... Engine, 12 ... Engine ECU, 13 ... In-vehicle LAN, 14 ... Ignition switch (IGSW), 21 ... Transmission / reception antenna, 41 ... Control unit, 42 ... Memory, 43 ... Counter, 61 ... Mode switching unit, 62 ... Vehicle ID transmission unit, 64 ... SEED Reading unit 65 ... Encryption key generation unit 67 67 Memory 81 Control unit 82 Operation unit 83 Display unit

Claims (5)

In a portable device registration system that has the same encryption key with a communication target and registers a portable device in which encrypted communication is performed with the control target control device using the encryption key in the control device.
The control device stores key generation logic for generating an encryption key from identification information unique to the communication target and a key generation code captured from outside.
The portable device stores an encryption key generation code unique to the portable device used when generating the encryption key, and the encryption key generated using the key generation logic,
The control device writes the identification information in the portable device to be registered through wireless communication with the portable device as the registration processing of the portable device, and takes in the encryption key generation code stored in the portable device. , Generating the encryption key from the key generation code using the key generation logic stored in the key generation code, and storing the generated encryption key,
The portable device includes a counter that counts the number of times of encrypted communication performed with the control device or the time from the start of encrypted communication,
The portable device performs the encrypted communication with the communication target at a pre-shipment maximum number of communication before the shipment after the registration of the identification information, and the value of the counter is the value before the shipment. When the number of deletions set above the maximum number of communication times has been reached, or when the deletion time set to be longer than the longest pre-shipment time that may take from the completion of registration of the identification information to shipping, A portable device registration system for deleting the encryption key generation code. In the portable device registration system according to claim 1,
The mobile device registration system, wherein the number of deletions is the maximum number of communication before shipment. In the portable device registration system according to claim 1,
The portable device registration system, wherein the deletion time is the longest time before shipment. In the portable device registration system according to any one of claims 1 to 3,
A database for storing the identification information stored in the control device before shipment in association with the additional registration encryption key or the additional registration encryption key generation code;
The portable device and the control device manufactured for replenishment include the identification information stored in the database, the encryption key for additional registration, or the encryption key generated from the encryption key generation code for additional registration. Mobile device registration system that is manufactured in a state where is stored. In the portable device registration system according to any one of claims 1 to 4,
The control device is a portable device registration system in which the key generation logic is deleted after use.