JP2011172000A - Authentication system and authentication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an authentication system capable of increasing a security level. <P>SOLUTION: In the authentication system, when a battery pack BP is mounted on a vehicle body CA, the vehicle body CA authenticates the battery pack BP, and power supply from the battery pack BP to the vehicle body CA is permitted on condition that authentication is established. In this case, in the nonvolatile memory 16a of the vehicle body CA, authentication side identification codes set respectively for the plurality of vehicle bodies CA, authentication side encryption keys respectively set for the plurality of vehicle bodies CA similarly, and a common encryption algorithm are stored. Also, in the nonvolatile memory 24a of the battery pack BP, authentication target side identification codes set respectively for the plurality of battery packs BP, authentication target side encryption keys respectively set for the plurality of battery packs BP similarly, and the common encryption algorithm are stored. Then, the vehicle body CA authenticates the battery pack BP on the basis of the various kinds of data stored in the respective memories 16a, 24a. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an authentication system and an authentication method for performing authentication between any one of a plurality of authentication devices and any one of a plurality of devices to be authenticated.

  2. Description of the Related Art Conventionally, many electronic devices such as a mobile phone and an electric vehicle use a battery pack collected in a certain container as an operation power source so that the battery can be easily handled. Such a battery pack is generally constituted by a secondary battery, and can be repeatedly used by charging it periodically. On the other hand, since the secondary battery constituting the battery pack deteriorates due to, for example, a charge / discharge cycle, a use environment, a storage state, and the like, the battery pack can be usually replaced with a new one in the electronic device. It is like that.

  By the way, when replacing a battery pack, it is a principle to replace it with a regular battery pack that is certified by the manufacturer, but the user purchases a non-genuine battery pack that is cheaper than the regular battery pack. In some cases, this is mounted on an electronic device. However, when such an unauthorized battery pack is attached to an electronic device, not only cannot the normal operation of the electronic device be ensured, but also various electronic components mounted on the electronic device are worsened. May cause inconvenience such as damage.

  Therefore, normally, as seen in Patent Document 1, for example, when a battery pack is attached to an electronic device, authentication is performed as to whether or not the attached battery pack is genuine, and the battery pack is authorized. If it is determined that it is not, the connection between the electronic device and the battery pack is cut off. According to such an authentication system, even if an unauthorized battery pack is mounted on an electronic device, power is not supplied from the unauthorized battery pack to the electronic device. Damage can be prevented in advance.

JP 2005-151368 A

  By the way, in such an authentication system, it is conceivable to employ, for example, a challenge response authentication method as an authentication method of the battery pack. Here, the challenge-response authentication method is a method in which an electronic device and a battery pack have a common encryption key, and authentication is performed based on a result of encrypting a random number (challenge code) with a common encryption key. is there. If such a challenge-response authentication method is adopted as an authentication method for the battery pack, a common encryption key is not transmitted as it is, so that data exchanged between the electronic device and the battery pack is temporarily not possible. Even if eavesdropping by a third party, the information on the encryption key does not leak to the third party. Therefore, since unauthorized use of the encryption key by a third party can be prevented in advance, the security level can be maintained high.

  However, in such an authentication system, since a common encryption key is used for all electronic devices and battery packs, the encryption key of one electronic device or the encryption key of one battery pack is assumed to be a third party for some reason. In such a case, a third party can know the encryption keys of all electronic devices. For this reason, if a third party may manufacture an unauthorized battery pack using this leaked encryption key, there is a concern that the unauthorized battery pack will be used in all electronic devices, The security level as an authentication system may be significantly reduced.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an authentication system and an authentication method capable of increasing the security level.

  In order to solve the above-described problem, the invention described in claim 1 is provided between any one of the plurality of authentication devices and any one of the plurality of devices to be authenticated. In the authentication system that performs authentication in the authentication system, the plurality of authentication devices are set individually for each authentication side identification code set for each, an authentication side encryption key set for each separately, and for each of the plurality of devices to be authenticated Each of the plurality of devices to be authenticated from the authenticated side identification code is provided with a logic to be authenticated for calculating an authentication target side encryption key and a storage unit for storing a common encryption algorithm, After calculating the first encrypted random number by generating the first random number and encrypting the first random number using the common encryption algorithm and the authentication-side encryption key, the calculated first encrypted random number Authentication side knowledge A plurality of devices to be authenticated to calculate the authentication-side encryption key from the authentication-side identification code, the authentication-side encryption key, and the authentication-side identification code. Each of the authentication side logic and the storage unit for storing the common encryption algorithm, after calculating the authentication side encryption key based on the authentication side logic from the authentication side identification code transmitted from the authentication device, A second random number is obtained by decrypting the first encrypted random number using the same authentication-side encryption key that has been calculated, and the acquired second random number is used as the common encryption algorithm and the authenticated-side encryption. A second encrypted random number is calculated by encrypting with a key, and the calculated second encrypted random number is transmitted to the authentication device together with the authentication target side identification code. The plurality of authentication devices calculate the authentication target side encryption key after calculating the authentication target side encryption key based on the authentication target side logic from the authentication target side identification code transmitted from the authentication target device. A third random number is obtained by decrypting the second encrypted random number using a key, and authentication of the device to be authenticated is performed based on a comparison between the obtained third random number and the first random number. The gist is to do.

The invention according to claim 4 is an authentication method for performing authentication between any one of the plurality of authentication devices and any one of the plurality of devices to be authenticated. The plurality of authentication devices are each configured as an authentication side identification code set for each of them, an authentication side encryption key set for each of the authentication devices, and an authentication target side identification set for each of the plurality of devices to be authenticated Each of the plurality of devices to be authenticated from the code includes a logic to be authenticated for calculating a key to be authenticated and a storage unit for storing a common encryption algorithm, and the plurality of devices to be authenticated The device stores the authentication target side identification code, the authentication target side encryption key, an authentication side logic for calculating the authentication side encryption key from the authentication side identification code, and the common encryption algorithm. Be those having parts respectively,
a. The authentication device generates a first random number and calculates the first encrypted random number by encrypting the first random number using the common encryption algorithm and the authentication side encryption key, and then calculating the first random number. A first step of transmitting the encrypted random number together with the authenticator identification code to the device to be authenticated; and
b. The device to be authenticated calculates the authentication side encryption key based on the authentication side logic from the authentication side identification code transmitted from the authentication device, and then uses the calculated authentication side encryption key. A second random number is obtained by decrypting the encrypted random number, and a second encryption is obtained by encrypting the obtained second random number using the common encryption algorithm and the authentication-target encryption key. A second step of calculating a random number, and transmitting the calculated second encrypted random number together with the authenticated side identification code to the authentication device; and
c. After the authentication device calculates the authenticated side encryption key based on the authenticated side logic from the authenticated side identification code transmitted from the authenticated device, the calculated authentication side encryption key is used. A third step of acquiring a third random number by decrypting the second encrypted random number and comparing the acquired third random number with the first random number, the authentication device The gist is to authenticate the device to be authenticated.

  According to the authentication system or the authentication method, since the encryption key used in the authentication device and the device to be authenticated can be made different from each other, the encryption key of the device to be authenticated has been leaked to a third party for some reason. In addition, it is possible to prevent leakage of the encryption key of the authentication device. Further, if different encryption keys are set for a plurality of authentication devices and different encryption keys are set for a plurality of devices to be authenticated, the encryption key of one authentication device or one Even if the encryption key of one device to be authenticated leaks to a third party for some reason, the third party cannot know the encryption keys of all the authentication devices. In other words, since it is possible to avoid a situation in which the encryption key used in all authentication devices leaks, the security level is higher than that in an authentication system that uses a common encryption key in all authentication devices and devices to be authenticated. Can be increased.

  The invention according to claim 2 is an authentication system for performing authentication between any one of a plurality of authentication devices and any one of a plurality of devices to be authenticated. The plurality of authentication devices are authentication side identification codes set for each of the plurality of authentication devices, and authentication side logic for calculating an authentication side encryption key set for each of the plurality of authentication devices from the authentication side identification code, Authentication target side logic for calculating the authentication target side encryption key set for each of the plurality of authentication devices from the authentication target side identification code set for each of the plurality of authentication target devices, and common encryption A storage unit for storing an algorithm; calculating an authentication-side encryption key from the authentication-side identification code based on the authentication-side logic; generating a first random number; After calculating a first encrypted random number by encrypting using a common encryption algorithm and the authentication side encryption key, the calculated first encrypted random number is transmitted to the device to be authenticated together with the authentication side identification code. The plurality of devices to be authenticated each include a storage unit for storing the authentication target identification code, the authentication logic, the logic to be authenticated, and the common encryption algorithm, Calculating the authentication-side encryption key from the authentication-side identification code transmitted from the authentication-side logic, and then decrypting the first encrypted random number using the calculated authentication-side encryption key. 2 is obtained, the authentication target side encryption key is calculated from the authentication target side identification code based on the authentication target side logic, and the second random number is calculated as the common encryption address. After calculating the second encrypted random number by encrypting using the algorithm and the authenticated side encryption key, the calculated second encrypted random number is transmitted to the authenticated device together with the authenticated side identification code. The plurality of authentication devices calculate the authentication target side encryption key based on the authentication target side logic from the authentication target side identification code transmitted from the device to be authenticated, and then calculate the same authentication target A third random number is obtained by decrypting the second encrypted random number using the side encryption key, and the authentication target device is configured based on the comparison between the obtained third random number and the first random number. The gist is to perform authentication.

  According to this system, since it is not necessary to store the encryption key in the authentication device and the device to be authenticated, it is possible to prevent leakage of the authentication side encryption key and the authentication side encryption key. For this reason, a security level can be raised compared with the authentication system which uses a common encryption key with all the authentication apparatuses and to-be-authenticated apparatuses.

  According to a third aspect of the present invention, in the authentication system according to the first or second aspect, an identification code of a device to be authenticated that should be prohibited from authentication is stored in the storage unit of the authentication device, and the plurality of authentications The gist of the device is to determine that the authentication is not established when the authentication target side identification code transmitted from the device to be authenticated matches the identification code to be prohibited.

  According to this system, even if a third party manufactures a counterfeit product based on a specific device to be authenticated, so-called dead copy is performed, authentication of the identification code of the device to be authenticated that has been dead copied is prohibited. If the identification code to be stored is stored in the storage unit of the authentication device, establishment of authentication of the device to be authenticated that has been dead copied can be prohibited. For this reason, the security level can be further increased.

  According to the authentication system and the authentication method according to the present invention, the security level can be increased.

The block diagram which shows the system configuration | structure of the authentication system of the vehicle using the authentication system about one Embodiment of the authentication system concerning this invention. (A), (b) is a figure which shows typically the data memorize | stored in the non-volatile memory of a vehicle main body, and the data memorize | stored in the non-volatile memory of a battery pack about the authentication system of the embodiment. (A), (b) each shows the procedure of the process performed by a vehicle control part, and the process performed by a battery control part, when a battery pack is mounted | worn with the vehicle main body about the authentication system of the embodiment. flowchart. The flowchart which shows the procedure of the process performed by a vehicle control part, when a battery pack is mounted | worn with the vehicle main body about the authentication system of the embodiment. (A), (b) shows typically the data memorize | stored in the non-volatile memory of a vehicle main body, and the data memorize | stored in the non-volatile memory of a battery pack about the modification of the authentication system concerning this invention. Figure. (A), (b) shows the procedure of the process performed by a vehicle control part when a battery pack is mounted | worn with the vehicle main body about the authentication system of the modification, and the process performed by a battery control part, respectively. flowchart.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment in which an authentication system according to the present invention is applied to a vehicle authentication system will be described with reference to FIGS. FIG. 1 is a block diagram showing the system configuration of this vehicle authentication system.

  As shown in FIG. 1, this vehicle is a so-called electric vehicle, and is largely a vehicle main body CA that uses a motor 10 as a drive source, and is detachably mounted on the vehicle main body CA and the motor 10. The battery pack BP functions as an operating power source.

  Here, the vehicle body CA is provided with an inverter circuit 12 that converts DC power supplied from the battery pack BP via the connection terminal 11 into three-phase AC power, and the inverter circuit 12 converts the DC power. Three-phase AC power is supplied to the motor 10. The motor 10 is a so-called three-phase AC motor, and is driven by three-phase AC power supplied from the inverter circuit 12. Note that a switch 13 is provided between the connection terminal 11 and the inverter circuit 12 so as to intermittently connect the connection. The switch 13 is turned on / off to connect the battery pack BP to the inverter circuit 12. It is possible to intermittently supply power. Further, the vehicle body CA is provided with a communication unit 15 connected to the battery pack BP via the connection terminal 14, and exchange of various data with the battery pack BP is performed via the communication unit 15. Done. Then, drive control of the motor 10 through the inverter circuit 12, on / off switching of the switch 13, and communication control through the communication unit 15 are collectively performed through the vehicle control unit 16. Incidentally, the vehicle control unit 16 includes an arithmetic processing unit (CPU), a data memory (RAM) as a storage unit, a non-volatile memory 16a, and the like.

  On the other hand, the battery pack BP is provided with an assembled battery 20 in which a plurality of secondary batteries such as a lithium ion secondary battery and a nickel hydride secondary battery are combined, and the DC power stored in the assembled battery 20 is provided. Is supplied to the vehicle main body CA via the connection terminal 21. In addition, the battery pack BP is provided with a communication unit 23 connected to the vehicle main body CA via the connection terminal 22, and exchange of various data with the vehicle main body CA is performed via the communication unit 23. Done. Communication control through the communication unit 23 is performed through the battery control unit 24. Incidentally, the battery control unit 24 also includes an arithmetic processing unit (CPU), a data memory (RAM) as a storage unit, a nonvolatile memory 24a, and the like.

  In the authentication system configured as described above, if the battery pack BP is mounted on the vehicle main body CA, the vehicle main body CA and the battery pack BP operate as follows. First, when the battery pack BP is attached to the vehicle main body CA, the connection terminal 11 of the vehicle main body CA and the connection terminal 21 of the battery pack BP are connected to each other so that power can be supplied from the battery pack BP to the vehicle main body CA. . At this time, the connection terminal 14 of the vehicle main body CA and the connection terminal 22 of the battery pack BP are also connected, and communication between the vehicle control unit 16 and the battery control unit 24 becomes possible. When the vehicle control unit 16 can communicate with the battery control unit 24 as described above, the vehicle control unit 16 determines that the battery pack BP is attached to the vehicle main body CA, and exchanges various data with the battery control unit 24. To authenticate the battery pack BP. When the vehicle control unit 16 determines that the authentication of the battery pack BP has been established, the vehicle control unit 16 turns on the switch 13 to permit power supply from the battery pack BP to the vehicle main body CA. On the other hand, when determining that the authentication of the battery pack BP is not established, the vehicle control unit 16 turns off the switch 13 to prohibit power supply from the battery pack BP to the vehicle main body CA.

  By the way, in such an authentication system, as described above, after having a common encryption key in a plurality of vehicle main bodies CA and a plurality of battery packs BP, a battery pack using this common encryption key is used. When BP authentication is performed, the following problems may occur. That is, if the encryption key of one vehicle body CA or the encryption key of one battery pack BP is leaked to a third party for some reason, all the encryption keys of the vehicle body CA are known to the third party. End up. For this reason, if a third party manufactures an unauthorized battery pack using the leaked encryption key, authentication of the unauthorized battery pack is established in a plurality of vehicle main bodies CA. The security level may be significantly reduced.

  Therefore, in this embodiment, after setting an encryption key for each of the plurality of vehicle main bodies CA and for each of the plurality of battery packs BP, the authentication of the battery pack BP is performed using these encryption keys. ing.

  On the other hand, even if the encryption key is set in this way, if a third party manufactures a counterfeit product based on a specific battery pack, so-called dead copy may be performed, this dead copied battery pack There is also a concern that the authentication may be established by a plurality of vehicle main bodies CA.

  Therefore, in the present embodiment, the vehicle control unit 16 further sets an identification code (ID code) for each of the plurality of battery packs BP, and uses the dead-copied battery pack identification code as an authentication prohibition identification code. It is made to memorize | store in the non-volatile memory 16a. Then, when authenticating the battery pack BP, the identification code of the battery pack BP and the authentication prohibition identification code are collated, and when the identification codes match, the authentication of the battery pack BP is prohibited. ing.

  Next, in order to authenticate such a battery pack BP, the data stored in the nonvolatile memory 16a of the vehicle control unit 16 and the nonvolatile memory 24a of the battery control unit 24 are respectively shown in FIGS. ) Will be described.

  As shown in FIGS. 2A and 2B, the following data (a1) to (a8) are stored in the nonvolatile memory 16a of the vehicle control unit 16 and the nonvolatile memory 24a of the battery control unit 24. Are stored. However, “m” and “n” represent an integer of 2 or more.

(A1) a plurality of vehicle body _CA 1 to CA _m authenticator is configured to separately for each identification code _IDA 1 _{~IDA m.} This data is stored in the non-volatile memory 16a of each of the vehicle bodies CA _{1 to} CA _m .

(A2) a plurality of battery packs _BP 1 to BP _n authenticated side is set to each other for each identification code _IDB 1 _{~IDB n.} This data is stored respectively in the nonvolatile memory 24a of the battery pack _BP 1 to BP _n.

(A3) a plurality of vehicle body _CA 1 to CA authenticator encryption key is set to each different for each _{m KA} 1 _{~KA m.} This data is stored in the non-volatile memory 16a of each of the vehicle bodies CA _{1 to} CA _m .

(A4) a plurality of battery packs _BP 1 to BP _n authenticated side encryption key _KB is set to each other every ₁ ~KB n. This data is stored respectively in the nonvolatile memory 24a of the battery pack _BP 1 to BP _n.

(A5) the authenticator identification code _IDA 1 _{~IDA m} above authenticator encryption key from _KA 1 _{~KA m} authenticator logic for calculating the LA. This data is stored respectively in the nonvolatile memory 24a of the battery pack _BP 1 to BP _n. The following expression (1) is established between the authentication side identification codes IDA _{1 to} IDA _m , the authentication side encryption keys KA _{1 to} KA _m , and the authentication side logic LA (where i = _{1 to m} ).

KA _i = LA (IDA _m ) (1)
(A6) the authenticated side identification code _IDB 1 _{~IDB n} from the authenticated side encryption key _KB 1 _{~KB n} authenticated side logic for calculating. This data is stored in the non-volatile memory 16a of each of the vehicle bodies CA _{1 to} CA _m . It should be noted that the following expression (2) is established among the authenticated side identification codes IDB _{1 to} IDB _n , the authenticated side encryption keys KB _{1 to} KB _n , and the authenticated side logic LB (where j = 1 to n ).

KB _j = LB (IDB _n ) (2)
(A7) Common encryption algorithm. This data is stored in the non-volatile memory 16a of the vehicle bodies CA _{1 to} CA _{m and} the non-volatile memory 24a of the battery packs BP _{1 to} BP _n , respectively. The common encryption algorithm is a program that encrypts input data based on an encryption method such as DES (Data Encryption Standard) or AES (Advanced Encryption Standard).

(A8) The authentication prohibition identification code IDBs corresponding to the identification code of the battery pack that prohibits the authentication among the authentication target side identification codes IDB _{1 to} IDB _n . This data is stored in the non-volatile memory 16a of each of the vehicle bodies CA _{1 to} CA _m .

  If there are a plurality of battery packs that prohibit authentication, the identification codes of the corresponding battery packs are stored in the nonvolatile memory 16a as authentication prohibition identification codes IDBs. The information of the authentication prohibition identification code IDBs is managed by, for example, a database held by a dealer, and is sequentially updated by the dealer at the time of vehicle inspection.

Next, with reference to FIG. 3 and FIG. 4, a process executed through the vehicle control unit 16 and the battery control unit 24 when the battery pack BP _j is mounted on the vehicle main body CA _i will be described (however, i = 1 to m, j = 1 to n).

3 and 4 are flowcharts showing the procedure of these processes.
As shown in FIG. 3A, in the process executed through the vehicle control unit 16, first the first random number C1 is generated (step S10), and the generated first random number C1 is Encryption is performed using the common encryption algorithm F and the authentication side encryption key KA _i stored in the nonvolatile memory 16a (step S11). Then, as the processing of the subsequent step S12, the challenge signal is generated by adding the authentication side identification code IDA _i stored in the nonvolatile memory 16a to the generated first encrypted random number F (C1, KA _i ). The generated challenge signal is transmitted to the battery pack BP _j via the communication unit 15 (step S13).

On the other hand, as shown in FIG. 3 (b), the processing to be executed via the battery control unit 24, first, whether the challenge signal from the vehicle body CA _i is transmitted is determined (step S30). Here, when the challenge signal transmitted from the vehicle body CA _i is received via the communication unit 23 (step S30: YES), the authentication side identification code IDA _i included in the challenge signal, and the nonvolatile The authentication side encryption key KA _i is calculated from the authentication side logic LA stored in the memory 24a based on the above equation (1) (step S31). In the subsequent step S32, using the calculated authentication-side encryption key KA _i and the common encryption algorithm F stored in the non-volatile memory 24a, the first challenge included in the received challenge signal. The second random number C2 is obtained by decrypting the encrypted random number F (C1, KA _i ). The acquired second random number C2 is encrypted using the common encryption algorithm F and the authenticated side encryption key KB _j stored in the non-volatile memory 24a (step S33). A response signal is generated by adding the authenticated side identification code IDB _j stored in the non-volatile memory 24a to the encrypted random number F (C2, KB _j ) of No. 2 (step S34). Further, in the subsequent step S35, the generated response signal is transmitted to the vehicle main body CA _i via the communication unit 23, and the battery control unit 24 ends the series of processes.

On the other hand, as shown in FIG. 3A, in the process executed through the vehicle control unit 16, it is determined whether or not a response signal has been received following the process of step S13 (step S14). . Here, when the response signal transmitted from the battery pack BP _j is received via the communication unit 15 (step S14: YES), as shown in FIG. 4, the response signal is processed as the subsequent step S15. It is determined whether or not the authenticated-side identification code IDB _j included in the authentication-inhibited identification code IDBs stored in the nonvolatile memory 16a. In the process of step S15, the authenticated-side identification code IDB _j is compared with the authentication-prohibited identification code IDBs, and when it is determined that the identification codes match each other, the authenticated-side identification code IDB _j is It is determined that the authentication prohibition identification code IDBs. If it is determined through the processing in step S15 that the authentication-target identification code IDB _j is the authentication prohibition identification code IDBs (step S15: YES), the authentication of the battery pack BP _j is not established. The switch 13 is turned off in order to prohibit power supply from the battery pack BP _j to the vehicle main body CA _i (step S20). And after performing the process of this step S20, the vehicle control part 16 complete | finishes this series of processes.

On the other hand, if it is determined through the process of step S15 that the authenticated-side identification code IDB _j is not the authentication-prohibited identification code IDBs (step S15: NO), the authenticated-side identification included in the received response signal The authenticated side encryption key KB _j is calculated from the code IDB _j and the authenticated side logic LB stored in the nonvolatile memory 16a based on the above equation (2) (step S16). Then, in the subsequent step S17, based on the calculated encryption key KB _j to be authenticated and the common encryption algorithm F stored in the non-volatile memory 16a, the above-mentioned first included in the received response signal. The third random number C3 is obtained by decrypting the encrypted random number F (C2, KB _j ) of 2. Further, it is determined whether or not the acquired third random number C3 and the first random number C1 calculated through the process of step S11 are matched with each other (step S18), and the respective random numbers are matched with each other. If it is determined to do so (step S18: YES), the switch 13 is turned on to allow power supply from the battery pack BP _j to the vehicle body CA _i (step S19). And following the process of this step S20, the vehicle control part 16 once complete | finishes this series of processes.

If it is determined through the process of step S18 that the first random number C1 and the third random number C3 do not match each other (step S18: NO), the battery pack BP _{j is transferred} to the vehicle body CA _i . The switch 13 is turned off in order to prohibit the power supply (step S20), and the vehicle control unit 16 ends this series of processes.

According to such a configuration as a vehicle authentication system, the data shown in the above (a1) to (a8) is correctly stored in the nonvolatile memory 16a of the vehicle control unit 16 and the nonvolatile memory 24a of the battery control unit 24. Then, the first to third random numbers C1 to C3 all have the same value. That is, in this case, since the authentication of the battery pack BP _j is properly established, power supply from the battery pack BP _j to the vehicle main body CA _i is permitted.

On the other hand, in the present embodiment, while the battery pack BP _j is appropriately authenticated as described above, the encryption keys used in the vehicle main body CA _i and the battery pack BP _j are different from each other. Therefore, for some reason, the battery pack BP _j Even if the authentication-side encryption key KB _j is leaked, the authentication-side encryption key KA _i of the vehicle main body CA _i can be prevented from leaking. Further, the different authentication-side encryption key _KA 1 _{~KA m} are respectively set to each other with respect to a plurality of vehicle body _CA 1 to CA _m, different authenticated side against a plurality of battery packs _BP 1 to BP _n since the encryption key _KB 1 _{~KB n} are respectively set, if one vehicle body CA _i encryption key KA _i or encryption keys KA _i of one battery pack BP _j, the leaks to a third party for some reason Even so, the third party cannot know the encryption keys of all the vehicle main bodies CA _{1 to} CA _m . In other words, since it is possible to avoid a situation in which the encryption keys used in all the vehicle main bodies CA _{1 to} CA _m leak, an authentication system that uses an encryption key common to all the vehicle main bodies CA and the battery packs BP. Compared with, the security level can be increased.

Furthermore, in the present embodiment, even if a third party were dead copy the particular battery pack BP _j, nonvolatile vehicle controller 16 the identification code of the particular battery pack BP _j as the authentication prohibited identification code IDBs By storing it in the memory 16a, it becomes possible to prevent the use of the battery pack that has been dead copied. For this reason, the security level as a system can be further increased.

As described above, according to the vehicle authentication system of the present embodiment, the following effects can be obtained.
(1) Different authentication-side encryption keys KA _{1 to} KA _m are set for the plurality of vehicle main bodies CA _{1 to} CA _m , and different authentication-side encryptions are also used for the plurality of battery packs BP _{1 to} BP _n . Keys KB _{1 to} KB _n are set. Then, the battery pack BP is authenticated using the encryption keys KA _{1 to} KA _m and KB _{1 to} KB _n set in this way. Accordingly, it is possible to prevent a plurality of vehicle body _CA 1 leakage authenticator encryption key _KA 1 _{~KA m} used in to CA _m, it is possible to enhance the security level.

(2) The authentication prohibited identification code IDBs is stored in the non-volatile memory 16a of the vehicle control unit 16, and then the authenticated-side identification code IDB _j included in the response signal transmitted from the battery pack BP _j when the authentication prohibition identification code IDBs coincide with each other, authentication of the battery pack BP _j was set to determine the effect is not established. As a result, the use of the dead copied battery pack can be prevented, and the security level can be further increased.

In addition, the said embodiment can also be implemented with the following forms which changed this suitably.
As shown in FIG. 5, the authentication side logic LA may be stored in the nonvolatile memory 16a of the vehicle main body CA _i instead of the authentication side encryption key KA _i . Further, the non-authenticated side logic LB may be stored in the non-volatile memory 24a of the battery pack BP _{j in place} of the authenticated side encryption key KB _j . When such a configuration is adopted, as shown in FIG. 6A as a diagram corresponding to FIG. 3A, the vehicle control unit 16 uses the first random number in the process of step S10, for example. After generating C1, as the processing of subsequent step S21, the authentication side encryption key KA _i is calculated based on the authentication side logic LA from the authentication side identification code IDA _i stored in the nonvolatile memory 16a. Further, as shown in FIG. 6B as a diagram corresponding to FIG. 3B, the battery control unit 24 generates the second random number C2 through the process of step S32, for example, and then continues to step S36. As a process, the authenticated side encryption key KB _j is calculated based on the authenticated side logic LB from the authenticated side identification code IDB _j stored in the nonvolatile memory 24a. If such a configuration is adopted as the vehicle authentication system, it is not necessary to store the encryption key in the vehicle main body CA _i and the battery pack BP _j , so that the authentication side encryption key KA _i and the authentication side encryption key KB _j are leaked. Can be prevented in advance. Therefore, when compared with the authentication system using a common encryption key for all of the vehicle main body _CA 1 to CA _m and the battery pack _BP 1 to BP _n, it is possible to enhance the security level.

In the above embodiment, when the authenticated side identification code IDB _j and the authentication prohibition identification code IDBs included in the response signal transmitted from the battery pack BP _j match each other, the authentication of the battery pack BP _j is not established. Although it is determined that there is, it is possible to omit this determination process. According to such a configuration, since it is not necessary to store the authentication prohibition identification code IDBs in the nonvolatile memory 16a of the vehicle control unit 16, it is possible to secure a capacity margin of the nonvolatile memory 16a accordingly. become.

In the above embodiment, the authentication system according to the present invention is applied to the vehicle authentication system, and the vehicle body CA is used as the authentication device and the battery pack BP is used as the device to be authenticated. May be, for example, a mobile phone, a notebook computer, or a digital camera. Further, the device to be authenticated may be, for example, a memory card or various adapter devices. In short, the authentication according to the present invention is applicable to any system that performs authentication between any one of the plurality of authentication devices and any one of the plurality of devices to be authenticated. It is possible to apply the system.
(Appendix)
Next, a technical idea that can be grasped from the above embodiment and its modifications will be additionally described.

  (A) In the authentication system according to any one of claims 1 to 3, the authentication device is a vehicle body that uses a motor that operates by power feeding from a secondary battery as a drive source, and the device to be authenticated is An authentication system characterized by being a battery pack constituted by the secondary battery. As described above, in an authentication system in which the authentication device is a vehicle main body and the device to be authenticated is a battery pack, there is a concern about a decrease in security due to leakage of the encryption key. Therefore, it is significant to apply the authentication system according to any one of claims 1 to 3 to such an authentication system.

  BP ... Battery pack, CA ... Vehicle body, 10 ... Motor, 11, 14, 21, 22 ... Connection terminal, 12 ... Inverter circuit, 13 ... Switch, 15,23 ... Communication unit, 16 ... Vehicle control unit, 16a, 24a ... non-volatile memory, 20 ... assembled battery, 24 ... battery control unit, 24a ... non-volatile memory.

Claims (4)

In an authentication system that performs authentication between any one of a plurality of authentication devices and any one of the plurality of devices to be authenticated,
The plurality of authentication devices include authentication side identification codes set for each of the authentication devices, authentication side encryption keys set for the respective authentication devices, and authentication target side identification codes set for each of the plurality of authentication target devices. Each of the plurality of devices to be authenticated includes an authentication target side logic for calculating an authentication target side encryption key and a storage unit for storing a common encryption algorithm, and generates a first random number. This is encrypted using the common encryption algorithm and the authentication-side encryption key to calculate a first encrypted random number, and then the calculated first encrypted random number together with the authentication-side identification code is calculated. Which is sent to the authentication device,
The plurality of devices to be authenticated store the authentication target side identification code, the authentication target side encryption key, an authentication side logic for calculating the authentication side encryption key from the authentication side identification code, and the common encryption algorithm Each of the storage units, and after calculating the authentication side encryption key based on the authentication side logic from the authentication side identification code transmitted from the authentication device, the first authentication side using the calculated authentication side encryption key The second random number is obtained by decrypting the encrypted random number and the second random number is obtained by encrypting the obtained second random number using the common encryption algorithm and the authentication-side encryption key. Calculating the encrypted random number, and transmitting the calculated second encrypted random number together with the authenticated side identification code to the authentication device,
The plurality of authentication devices calculate the authentication target side encryption key from the authentication target side identification code transmitted from the device to be authenticated based on the authentication target side logic, and then calculate the authentication target side encryption key. A third random number is obtained by decrypting the second encrypted random number and authenticating the device to be authenticated based on a comparison between the obtained third random number and the first random number. An authentication system characterized by In an authentication system that performs authentication between any one of a plurality of authentication devices and any one of the plurality of devices to be authenticated,
The plurality of authentication devices are authentication side identification codes set for each of the plurality of authentication devices, and authentication side logic for calculating an authentication side encryption key set for each of the plurality of authentication devices from the authentication side identification code, Authentication target side logic for calculating the authentication target side encryption key set for each of the plurality of authentication devices from the authentication target side identification code set for each of the plurality of authentication target devices, and common encryption Each of the storage units stores an algorithm, calculates the authentication-side encryption key based on the authentication-side logic from the authentication-side identification code, generates a first random number, and generates the generated first random number After calculating the first encrypted random number by encrypting using a common encryption algorithm and the authentication side encryption key, the calculated first encrypted random number together with the authentication side identification code is calculated. Is intended to be sent to the authentication device,
The plurality of devices to be authenticated each include a storage unit that stores the identification code to be authenticated, the logic to be authenticated, the logic to be authenticated, and the common encryption algorithm, and transmitted from the authentication device. After calculating the authentication side encryption key based on the authentication side logic from the side identification code, a second random number is obtained by decrypting the first encrypted random number using the calculated authentication side encryption key And calculating the authentication target side encryption key from the authentication target side identification code based on the authentication target side logic and encrypting the second random number using the common encryption algorithm and the authentication target side encryption key. Then, after calculating the second encrypted random number, the calculated second encrypted random number is transmitted to the authentication device together with the authenticated side identification code,
The plurality of authentication devices calculate the authentication target side encryption key from the authentication target side identification code transmitted from the device to be authenticated based on the authentication target side logic, and then calculate the authentication target side encryption key. A third random number is obtained by decrypting the second encrypted random number and authenticating the device to be authenticated based on a comparison between the obtained third random number and the first random number. An authentication system characterized by In the storage unit of the authentication device, an identification code of the device to be authenticated to be prohibited is stored, and the plurality of authentication devices are prohibited by the authentication-side identification code transmitted from the device to be authenticated. The authentication system according to claim 1, wherein when it matches the power identification code, it is determined that the authentication is not established. In the authentication method for performing authentication between any one of the plurality of authentication devices and any one of the plurality of devices to be authenticated,
The plurality of authentication devices include authentication side identification codes set for each of the authentication devices, authentication side encryption keys set for the respective authentication devices, and authentication target side identification codes set for each of the plurality of authentication target devices. Each of the plurality of devices to be authenticated includes a to-be-authenticated side logic for calculating a to-be-authenticated side encryption key, and a storage unit for storing a common encryption algorithm.
The plurality of devices to be authenticated store the authentication target side identification code, the authentication target side encryption key, an authentication side logic for calculating the authentication side encryption key from the authentication side identification code, and the common encryption algorithm Each of which has a storage unit,
a. The authentication device generates a first random number and calculates the first encrypted random number by encrypting the first random number using the common encryption algorithm and the authentication side encryption key, and then calculating the first random number. A first step of transmitting the encrypted random number together with the authenticator identification code to the device to be authenticated; and
b. The device to be authenticated calculates the authentication side encryption key based on the authentication side logic from the authentication side identification code transmitted from the authentication device, and then uses the calculated authentication side encryption key. A second random number is obtained by decrypting the encrypted random number, and a second encryption is obtained by encrypting the obtained second random number using the common encryption algorithm and the authentication-target encryption key. A second step of calculating a random number, and transmitting the calculated second encrypted random number together with the authenticated side identification code to the authentication device; and
c. After the authentication device calculates the authenticated side encryption key based on the authenticated side logic from the authenticated side identification code transmitted from the authenticated device, the calculated authentication side encryption key is used. A third step of obtaining a third random number by decrypting the second encrypted random number, and comparing the obtained third random number with the first random number;
Then, the authentication device authenticates the device to be authenticated.

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