Authentication system and authentication method

Abstract

To efficiently perform terminal authentication even in the case that a portable terminal of a user or a terminal of a store side is offline.SOLUTION: A user terminal 10 and a store terminal 20 mutually notify respective electronic certificates (S1). Mutual authentication is performed by using public keys e1, e2 and secret keys d1, d2 (S2). The user terminal 10 requests the store terminal 20 to relay terminal authentication with an authentication device 30 (S3), and the store terminal 20 relays the requested terminal authentication between the user terminal 10 and the authentication device 30 to notify the authentication device 30 of the terminal authentication (S4). The authentication device 30 notifies the store terminal 20 of a result obtained by performing terminal authentication of the user terminal 10 (S5). The terminal device 20 determines the permission / non-permission of a transaction with the user terminal 10 according to the received result of the terminal authentication (S6). When the result of the terminal authentication is valid, the transaction between the store terminal 20 and the user terminal 10 is started (S7).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an authentication system and an authentication method that can efficiently perform terminal authentication even when a user's mobile terminal such as a smartphone or tablet, or a store's terminal, is offline. [Background technology]

[0002] Traditionally, when a user purchases a product or receives a service at a store, the payment is usually made by cash or credit card. Recently, payments are sometimes made by credit card or electronic money using an application installed on the user's mobile device.

[0003] When making payments using such mobile terminals, since there are a wide variety of payment applications, various payment applications are installed in the terminals of the store. In this case, a technology is known in which the terminal of the store automatically selects an application to accommodate multiple payment applications installed on the mobile terminal (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2019-516190 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the above-mentioned Patent Document 1, the user's mobile terminal and the store's terminal each need to be connected online to an authentication device that performs terminal authentication processing and a payment agency center that performs payment processing. Therefore, if at least one of the terminals is offline, terminal authentication and payment processing cannot be performed, which may cause a disruption to business at the store. Therefore, how to perform terminal authentication and payment processing when the user's mobile terminal or the store's terminal is offline is an issue.

[0006] The present invention has been made to solve the problems of the conventional technology described above, and aims to provide an authentication system and authentication method that can efficiently perform terminal authentication even when the user's mobile terminal or the store's terminal is offline. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides an authentication system having a first terminal carried by a first user, a second terminal carried by a second user, and an authentication device that authenticates the first terminal and the second terminal, the system including a state determination means for determining whether the first terminal is in a state where it can communicate with the authentication device, and a relay request means for requesting the second terminal to relay authentication information when the state determination means determines that the first terminal is in a state where it cannot communicate, and an authentication information relay means for relaying the authentication information requested by the first terminal to the authentication device. a determination means for determining that a payment transaction through a predetermined payment system is possible if an authentication result indicating that the first terminal is legitimate is received from the authentication device, and determining that the payment transaction through the payment system is not possible if an authentication result indicating that the first terminal is not legitimate is received from the authentication device. an authentication processing means for performing authentication processing of the first terminal based on the authentication information, and an authentication result notifying means for notifying the second terminal of an authentication result by the authentication processing means. The present invention is characterized by comprising:

[0009] In the present invention, in the above-mentioned invention, the relay request means requests the second terminal to relay authentication information when a relay request is received from the second terminal.

[0012] In addition, in the above invention, the first terminal is equipped with a storage means for storing a private key assigned to the first terminal and specified authentication data, and an encryption means for generating authentication information by encrypting the authentication data stored in the storage means with the private key, and the authentication device is equipped with a decryption means for decrypting the authentication information with a public key assigned to the first terminal.

[0013] The present invention also relates to a method for storing a first user's The mobile device on which the card is registered and the second user has Reader / Writer And the above Mobile devices and the above Reader / Writer and an authentication device for authenticating the Mobile devices a state determination means for determining whether or not the authentication device is in a state where communication with the authentication device is possible; and Reader / Writer a relay requesting means for requesting the relay of authentication information to the Reader / Writer However, Mobile devices The authentication device includes an authentication information relay unit that relays authentication information requested from the authentication device to the authentication device. Mobile devices The present invention is characterized by comprising an authentication processing means for performing authentication processing of the above.

[0014] The present invention also provides an authentication method in an authentication system having a first terminal carried by a first user, a second terminal carried by a second user, and an authentication device that authenticates the first terminal and the second terminal, the method including a state determination step of determining whether the first terminal is in a state in which communication is possible with the authentication device, a relay request step of requesting the second terminal to relay authentication information when the first terminal is determined to be in a state in which communication is impossible by the state determination step, an authentication information relay step of the second terminal relaying the authentication information requested from the first terminal to the authentication device, and an authentication processing step of the authentication device performing authentication processing of the first terminal based on the authentication information. an authentication result notifying step in which the authentication device notifies the second terminal of an authentication result obtained by the authentication processing step; and a determination step in which the second terminal determines that a payment transaction is possible through a predetermined payment system if the second terminal receives from the authentication device an authentication result indicating that the first terminal is legitimate, and determines that the payment transaction is not possible through the payment system if the second terminal receives from the authentication device an authentication result indicating that the first terminal is not legitimate. The present invention is characterized by comprising: Effect of the Invention

[0015] According to the present invention, even when the user's mobile terminal or the store's terminal is offline, terminal authentication can be performed efficiently. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram illustrating an overview of an authentication system according to an embodiment. [Diagram 2] FIG. 2 is an explanatory diagram of an overview of terminal authentication according to the embodiment. [Diagram 3] FIG. 3 is a diagram showing a configuration of the user terminal shown in FIG. [Figure 4] FIG. 4 is a diagram showing an example of the electronic certificate data, the private key data, the authentication device public key data, the authentication data, and the payment information data shown in FIG. [Diagram 5] FIG. 5 is a diagram showing a configuration of the store terminal shown in FIG. [Figure 6] FIG. 6 is a diagram showing an example of the electronic certificate data, the private key data, the authentication device public key data, and the authentication data shown in FIG. [Figure 7] FIG. 7 is a diagram illustrating a configuration of the authentication device illustrated in FIG. [Figure 8] FIG. 8 is a diagram showing an example of the private key data, the registration terminal public key data, and the authentication data shown in FIG. [Figure 9] FIG. 9 is a flowchart showing a procedure of a terminal authentication process according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Preferred embodiments of an authentication system and an authentication method according to the present invention will be described in detail below with reference to the accompanying drawings. Note that in the following embodiments, the case where a public key cryptosystem called RSA cryptosystem is applied to the present invention will be mainly described.

[0018] <Overview of the authentication system according to this embodiment> First, an overview of the authentication system according to the present embodiment will be described. Fig. 1 is an explanatory diagram for explaining the overview of the authentication system according to the present embodiment. A user terminal 10 shown in Fig. 1 is a mobile communication terminal device such as a smartphone or tablet used by a customer who uses a store, and a store terminal 20 is a mobile communication terminal device such as a smartphone or tablet used by an employee of the store.

[0019] The user terminal 10 and the store terminal 20 can communicate with the authentication device 30 via wireless communication or Wi-Fi (registered trademark) communication provided by a communication carrier. A payment app for making payments at a store is installed in the store terminal 20. When the payment app is activated, the user terminal 10 accesses the authentication device 30 and receives terminal authentication.

[0020] Meanwhile, an encoding application that converts information required for payment processing, such as a credit card number, into a two-dimensional code is installed in the user terminal 10. Once the encoding application is started, the user terminal 10 and the store terminal 20 access the authentication device 30 and undergo terminal authentication.

[0021] If the authentication device 30 determines that the terminals are valid, the user terminal 10 and the store terminal 20 connect to a management device of a payment agency center (not shown) (hereinafter simply referred to as the "payment agency center") via a wireless communication network, making it possible to conduct transactions using the payment app.

[0022] If communication between the user terminal 10 and the authentication device 30 becomes impossible due to a failure or other reason, the terminal authentication of the user terminal 10 cannot be performed, and the payment application cannot be used. For this reason, it is desirable to enable terminal authentication of the user terminal 10 when the user terminal 10 and the authentication device 30 are offline.

[0023] Therefore, in the authentication system according to this embodiment, mutual authentication is performed between the user terminal 10, which is offline with the authentication device 30, and the store terminal 20, which is online with the authentication device 30, and then the store terminal 20 relays the authentication, thereby performing terminal authentication of the user terminal 10 by the authentication device 30. As a result, even if the user terminal 10 is offline with the authentication device 30, the user terminal 10 can receive terminal authentication by the authentication device 30 via the store terminal 20.

[0024] Next, an overview of each device will be described. As a preliminary step, it is assumed that a public key and a private key have been assigned in advance to the user terminal 10 and the store terminal 20, respectively. Specifically, it is assumed that an electronic certificate including a public key e1 and issued by the authentication device 30 and a private key d1 have been assigned to the user terminal 10, and an electronic certificate including a public key e2 and issued by the authentication device 30 and a private key d2 have been assigned to the store terminal 20. In addition, the public key e3 of the authentication device 30 has also been provided to the user terminal 10 and the store terminal 20 in advance.

[0025] The user terminal 10 is a mobile communication terminal device used by a customer who visits a store. The storage unit of the user terminal 10 stores an electronic certificate issued by the authentication device 30, including a public key e1, a private key d1, and a public key e3 of the authentication device 30.

[0026] In addition, the user terminal 10 is installed with a communication control application that controls wireless communication provided by the telecommunications carrier, Wi-Fi (registered trademark) communication, and short-range wireless communication such as BLUETOOTH (registered trademark), a terminal authentication application that performs terminal authentication with the authentication device 30, a mutual authentication application that performs mutual authentication with other terminal devices, an electronic signature application that issues an electronic signature using a private key, a restoration conversion application that performs restoration conversion of an electronic signature using a public key, an encryption application that performs encryption using a public key, and an encoding application that generates two-dimensional codes such as QR codes (registered trademark).

[0027] Furthermore, if the user terminal 10 is able to communicate with the store terminal 20 via short-range wireless communication such as BLUETOOTH (registered trademark), the user terminal 10 notifies the store terminal 20 of an electronic certificate including a public key e1, and receives an electronic certificate including a public key e2 from the store terminal 20. The user terminal 10 performs mutual authentication with the store terminal 20 using the private key d1, the public key e2, and authentication data.

[0028] Furthermore, when communication with the authentication device 30 is offline, the user terminal 10 notifies the store terminal 20 of a request to relay terminal authentication by the authentication device 30, and upon receiving a terminal authentication result from the store terminal 20, starts a transaction with the store terminal 20. Terminal authentication with the authentication device 30 is performed using a private key d1, a public key e3, and authentication data.

[0029] The user terminal 10 also uses the private key d1 to apply an electronic signature to payment information data, including a credit card number and the like, used to pay for purchases made in transactions with the store terminal 20, to generate signature data, and then encrypts the signature data with the public key e2 to generate encrypted data. The encrypted data is then converted into a two-dimensional code, and the two-dimensional code is displayed on the operation display unit. The encrypted data is then passed to the store terminal 20 by reading the two-dimensional code with the camera of the store terminal 20.

[0030] The store terminal 20 is a mobile communication terminal device such as a smartphone used by store employees. The store terminal 20 has a storage unit that stores an electronic certificate issued by the authentication device 30, including a public key e2, a private key d2, and a public key e3 of the authentication device 30.

[0031] In addition, the store terminal 20 is installed with the following applications: a communication control application that controls wireless communication provided by a telecommunications carrier, Wi-Fi (registered trademark) communication, and short-range wireless communication such as BLUETOOTH (registered trademark); a terminal authentication application that performs terminal authentication with the authentication device 30; a mutual authentication application that performs mutual authentication with other terminal devices; an electronic signature application that issues an electronic signature using a private key; a restoration conversion application that performs restoration conversion of an electronic signature using a public key; a decryption application that decrypts encrypted data using a private key; a payment processing application that performs payment processing with a payment agency center not shown; a code reading application that reads two-dimensional codes such as QR codes (registered trademark); a relay application that relays information related to a terminal authentication relay request when the relay request is received from another terminal device such as the user terminal 10; and a determination application that accepts and determines the authentication result for the relayed terminal authentication.

[0032] Furthermore, if the store terminal 20 is able to communicate with the user terminal 10 via short-range wireless communication such as BLUETOOTH (registered trademark), it notifies the user terminal 10 of an electronic certificate including a public key e2, and receives an electronic certificate including a public key e1 from the user terminal 10. The store terminal 20 performs mutual authentication with the user terminal 10 using the private key d2, the public key e1, and authentication data.

[0033] Furthermore, if the store terminal 20 is able to communicate with the authentication device 30 via wireless communication or the like provided by a communications carrier, the store terminal 20 performs terminal authentication using the private key d2, the public key e3, and the authentication data.

[0034] Furthermore, the store terminal 20 acquires encrypted data from the user terminal 10 by reading the two-dimensional code displayed by the user terminal 10 with a camera. The store terminal 20 decrypts the acquired encrypted data with private key d2 to generate signature data, and restores and converts this signature data with public key e1 to generate payment information data for the user terminal 10. The store terminal 20 performs payment processing using the generated payment information data for the user terminal 10.

[0035] Furthermore, when the store terminal 20 receives a request to relay terminal authentication from the user terminal 10, it notifies the authentication device 30 of information related to this relay request. The store terminal 20 receives an authentication result for the notified terminal authentication from the authentication device 30, and if it determines that this authentication result is valid, it starts payment processing.

[0036] The authentication device 30 is a device that issues electronic certificates related to terminal devices such as the user terminal 10 and the store terminal 20, and performs terminal authentication of the terminal devices. A private key d3 and public keys of all registered terminal devices are stored in the storage unit of the authentication device 30.

[0037] In addition, authentication device 30 has installed therein a key management program for managing keys for issuing electronic certificates, etc., a terminal authentication program for performing terminal authentication of terminal devices, an electronic signature program for issuing an electronic signature using a private key, and a restoration conversion program for performing restoration conversion of an electronic signature using a public key.

[0038] Furthermore, if the authentication device 30 is capable of communicating with terminal devices such as the user terminal 10 and the store terminal 20 via wireless communication or the like, it performs terminal authentication using the private key d3, the public key of each terminal device, and authentication data.

[0039] Next, an overview will be given of terminal authentication between terminal devices such as the user terminal 10 and the store terminal 20 and the authentication device 30, and mutual authentication between the user terminal 10 and the store terminal 20. Since terminal authentication and mutual authentication are performed in a similar manner, an overview of terminal authentication between the store terminal 20 and the authentication device 30 will be given here.

[0040] 2 is an explanatory diagram of an overview of terminal authentication according to an embodiment. Terminal authentication includes authentication performed by the store terminal 20 on the authentication device 30 (hereinafter referred to as "server authentication") and authentication performed by the authentication device 30 on the store terminal 20 (hereinafter referred to as "client authentication").

[0041] FIG. 2(a) shows the flow of server authentication, in which the store terminal 20 generates a random number and stores it in authentication data f2, applies an electronic signature to the authentication data f2 using the private key d2 to generate signature data g2 (S11), and notifies the authentication device 30 of the generated signature data g2 (S12).

[0042] The authentication device 30 performs restoration conversion on the received signature data g2 using the public key e2 to restore authentication data f2' (S13), applies an electronic signature to the restored authentication data f2' using the private key d3 to generate signature data g2' (S14), and notifies the store terminal 20 of the generated signature data g2' (S15).

[0043] The store terminal 20 performs restoration conversion on the received signature data g2' using the public key e3 to restore authentication data f2" (S16). If the restored authentication data f2" is identical to the authentication data f2, the store terminal 20 determines that the authentication device 30 is legitimate and authenticates it (S17).

[0044] Next, FIG. 2(b) shows the flow of client authentication, in which the authentication device 30 generates a random number and stores it in authentication data f3, applies an electronic signature to the authentication data f3 using the private key d3 to generate signature data g3 (S21), and notifies the store terminal 20 of the generated signature data g3 (S22).

[0045] The store terminal 20 performs restoration conversion on the received signature data g3 using the public key e3 to restore authentication data f3' (S23), applies an electronic signature to the restored authentication data f3' using the private key d2 to generate signature data g3' (S24), and notifies the authentication device 30 of the generated signature data g3' (S25).

[0046] The authentication device 30 performs restoration conversion on the received signature data g3' using the public key e2 to restore authentication data f3" (S26). If the restored authentication data f3" is identical to the authentication data f3, the authentication device 30 determines that the store terminal 20 is legitimate and authenticates it (S27).

[0047] In this manner, the store terminal 20 and the authentication device 30 mutually perform server authentication and client authentication, thereby performing terminal authentication.

[0048] In mutual authentication between the user terminal 10 and the store terminal 20, if the user terminal 10 and the store terminal 20 are capable of communicating via short-range wireless communication, they notify each other of their electronic certificates including their respective public keys, and the public key e2 is stored in the user terminal 10, and the public key e1 is stored in the store terminal 20. By using the public key, private key, and random numbers generated each time stored in the user terminal 10 and the store terminal 20, respectively, as authentication data, mutual authentication is performed between the user terminal 10 and the store terminal 20 in the same manner as terminal authentication.

[0049] Next, the flow of authentication processing of the terminal device according to this embodiment will be described with reference to Fig. 1. The store terminal 20 is connected online to the authentication device 30, and terminal authentication has already been completed. The user terminal 10 is in an offline state with the authentication device 30, and terminal authentication has not been completed.

[0050] If the user terminal 10 and the store terminal 20 are capable of communicating via short-range wireless communication, they notify each other of their electronic certificates including their respective public keys (S1), and the public key e2 is stored in the user terminal 10 and the public key e1 is stored in the store terminal 20.

[0051] Mutual authentication is performed between the user terminal 10 and the store terminal 20 using the public key e2 and private key d1 stored in the user terminal 10 and the public key e1 and private key d2 stored in the store terminal 20 (S2).

[0052] The user terminal 10 requests the store terminal 20 to relay terminal authentication with the authentication device 30 (S3), and the store terminal 20 relays the terminal authentication between the requested user terminal 10 and the authentication device 30 and notifies the authentication device 30 (S4).

[0053] Specifically, the store terminal 20 relays notifications between the user terminal 10 and the authentication device 30 corresponding to the notification of signature data g2 (S12), the notification of signature data g2' (S15), the notification of signature data g3 (S22), and the notification of signature data g3' (S25) shown in FIG. 2.

[0054] The authentication device 30 notifies the store terminal 20 of the result of terminal authentication of the user terminal 10 (S5). Specifically, the result of authentication of the terminal by the authentication device 30 (S27) shown in FIG. 2(b) is notified.

[0055] The store terminal 20 determines whether or not to permit a transaction with the user terminal 10 based on whether the received terminal authentication result is valid or invalid (S6). If the terminal authentication result for the user terminal 10 is valid, the transaction between the store terminal 20 and the user terminal 10 is started (S7).

[0056] As described above, in the authentication system according to this embodiment, when the user terminal 10 is offline with the authentication device 30 and the store terminal 20 is online with the authentication device 30, if the user terminal 10 and the store terminal 20 are able to communicate with each other via short-range wireless communication, the store terminal 20 is configured to relay information required for terminal authentication between the user terminal 10 and the authentication device 30. As a result, even if the user terminal 10 or the store terminal 20 is offline with the authentication device 30, terminal authentication can be performed efficiently using short-range communication.

[0057] <Configuration of User Terminal 10> Next, a description will be given of the configuration of the user terminal 10 shown in Fig. 1. Fig. 3 is a diagram showing the configuration of the user terminal 10 shown in Fig. 1. As shown in Fig. 3, the user terminal 10 has an operation display unit 11, a communication unit 13, a storage unit 14, and a control unit 15.

[0058] The operation display unit 11 is an input / output device such as a touch panel display that accepts operations related to transactions and displays two-dimensional codes related to payment information data. The communication unit 13 is an interface unit for performing data communication with the store terminal 20 and the like via a wireless communication network.

[0059] The storage unit 14 is a storage device including a hard disk drive, a non-volatile memory, etc. The storage unit 14 stores electronic certificate data 14a, private key data 14b, authentication device public key data 14c, authentication data 14d, and payment information data 14e.

[0060] The electronic certificate data 14a is data indicating an electronic certificate issued by the authentication device 30 to the user terminal 10, and includes a public key e1 assigned to the user terminal 10. The private key data 14b is data indicating a private key d1 assigned by the authentication device 30 to the user terminal 10.

[0061] The authentication device public key data 14c is data indicating the public key e3 assigned to the authentication device 30. The authentication data 14d is data used in terminal authentication with the authentication device 30 and mutual authentication with the store terminal 20. The authentication data 14d stores a random number generated for each authentication. The payment information data 14e is data indicating information necessary for payment processing, and includes a credit card number, etc.

[0062] The control unit 15 is a control unit that performs overall control of the user terminal 10, and includes a key management unit 15a, a communication control unit 15b, a terminal authentication control unit 15c, a mutual authentication control unit 15d, an electronic signature processing unit 15e, a restoration conversion processing unit 15f, an encryption processing unit 15g, a coding processing unit 15h, and a display control unit 15i. In practice, programs corresponding to these functional units are stored in a non-volatile memory such as a ROM (not shown), and these programs are loaded into a CPU (Central Processing Unit) and executed, thereby causing the key management unit 15a, the communication control unit 15b, the terminal authentication control unit 15c, the mutual authentication control unit 15d, the electronic signature processing unit 15e, the restoration conversion processing unit 15f, the encryption processing unit 15g, the coding processing unit 15h, and the display control unit 15i to execute processes corresponding thereto.

[0063] The key management unit 15a is a processing unit that manages the electronic certificate data 14a, the private key data 14b, and the authentication device public key data 14c. When the key management unit 15a receives the electronic certificate issued by the authentication device 30, the assigned private key, and the public key of the authentication device 30, the key management unit 15a stores them in the electronic certificate data 14a, the private key data 14b, and the authentication device public key data 14c, respectively.

[0064] The communication control unit 15b is a processing unit that controls wireless communication provided by a communication carrier, Wi-Fi (registered trademark) communication, and short-distance wireless communication such as BLUETOOTH (registered trademark). The communication control unit 15b determines whether or not communication with the authentication device 30 is possible via wireless communication or the like, and passes the determination result to the terminal authentication control unit 15c.

[0065] The terminal authentication control unit 15c is a processing unit that controls terminal authentication with the authentication device 30. When the terminal authentication control unit 15c receives from the communication control unit 15b a determination that communication with the authentication device 30 is possible, the terminal authentication control unit 15c generates a random number and stores it in authentication data 14d, and performs terminal authentication with the authentication device 30 by using the private key data 14b, the authentication device public key data 14c, and the authentication data 14d.

[0066] In addition, when the terminal authentication control unit 15c receives from the communication control unit 15b a determination that communication with the authentication device 30 is not possible, after the mutual authentication with another terminal device is completed by the mutual authentication control unit 15d, the terminal authentication control unit 15c requests the terminal device that has completed mutual authentication to relay the transmission and reception of information necessary for terminal authentication between the authentication device 30.

[0067] The mutual authentication control unit 15d is a processing unit that controls mutual authentication with other terminal devices. The mutual authentication control unit 15d notifies each other of electronic certificates including their public keys with other terminal devices that can communicate with each other by short-distance wireless communication such as BLUETOOTH (registered trademark). For example, if the other connected terminal device is the store terminal 20, the public key e2 is stored in the user terminal 10 and the public key e1 is stored in the store terminal 20 by mutually notifying the electronic certificates.

[0068] In addition, the mutual authentication control unit 15d generates a random number and stores it in the authentication data 14d, and performs mutual authentication with the other connected terminal device using the private key data 14b, a public key (e.g., public key e2) received from the other connected terminal device, and the authentication data 14d.

[0069] The electronic signature processing unit 15e is a processing unit that performs an electronic signature using a private key. The electronic signature processing unit 15e performs an electronic signature on the data to be electronically signed using the private key data 14b, and generates signature data. For example, if a prime number n commonly used in this authentication system is defined, the private key data 14b is "d1", and the data to be electronically signed is M, then: S=M^d1 mod n (1) The signature data S is generated by the above. In this embodiment, "^" indicates exponentiation and "mod" indicates modulus operation. The electronic signature described in this embodiment is also processed in the same manner.

[0070] The restoration conversion processing unit 15f is a processing unit that performs restoration conversion of the electronic signature using a public key. The restoration conversion processing unit 15f performs restoration conversion on the signature data using a public key (e.g., public key e2) corresponding to the private key used in the electronic signature, and restores the data before the electronic signature was applied. Specifically, if the data to be restored is M, the signature data is S, and the public key is e2, then M=S^e2 mod n (2 equations) The data to be restored is restored and converted.

[0071] The encryption processing unit 15g is a processing unit that performs encryption using a public key. The encryption processing unit 15g encrypts the signature data that is electronically signed on the payment information data 14e using a public key (e.g., public key e2) included in the electronic certificate received from another connected terminal device. For example, if the public key data is e2 and the signature data is S, then C=S^e2 mod n (3 equations) The encrypted data C is generated by

[0072] The coder 15h is a processor that codes the encrypted data into a two-dimensional code. Since two-dimensional coding is a well-known technique, a detailed description thereof will be omitted here. When the encrypted data is generated by the encryption processor 15g, the coder 15h codes the encrypted data into a two-dimensional code.

[0073] The display control unit 15i is a processing unit that displays the two-dimensional code on the operation display unit 11. The display control unit 15i displays on the operation display unit 11 the two-dimensional code that has been coded by the coding processing unit 15h.

[0074] Next, an example of data stored in the storage unit 14 of the user terminal 10 shown in Fig. 3 will be described. Fig. 4 is a diagram showing an example of the electronic certificate data 14a, the private key data 14b, the authentication device public key data 14c, the authentication data 14d, and the payment information data 14e shown in Fig. 3.

[0075] As shown in FIG. 4(a), the digital certificate data 14a indicates that the certification authority of the digital certificate issued by the authentication device 30 is "zxcvbnm2345678" and the public key is "qwertyu3456789".

[0076] As shown in Fig. 4(b), the private key data 14b indicates that the private key is "abcdefg1234567". Also, as shown in Fig. 4(c), the authentication device public key data 14c indicates that the authentication device public key is "poiuytr4567890". Also, as shown in Fig. 4(d), the authentication data 14d indicates that the authentication data is "5ag8e92ae4np".

[0077] As shown in FIG. 4(e), the payment information data 14e indicates that the name is "TARO TOKKYO" and the credit card number is "1234567890123456."

[0078] <Configuration of the store terminal 20> Next, a description will be given of the configuration of the store terminal 20 shown in Fig. 1. Fig. 5 is a diagram showing the configuration of the store terminal 20 shown in Fig. 1. As shown in Fig. 5, the store terminal 20 has an operation display unit 21, a camera 22, a communication unit 23, a storage unit 24, and a control unit 25.

[0079] The operation display unit 21 is an input / output device such as a touch panel display that accepts operations related to a transaction and displays the transaction details, etc. The camera 22 is an imaging device provided on the back surface, etc., of the store terminal 20. The communication unit 23 is an interface unit for performing data communication with the authentication device 30, etc. via a wireless communication network.

[0080] The storage unit 24 is a storage device including a hard disk drive, a non-volatile memory, etc. The storage unit 24 stores electronic certificate data 24a, private key data 24b, authentication device public key data 24c, and authentication data 24d.

[0081] The electronic certificate data 24a is data indicating an electronic certificate issued by the authentication device 30 to the store terminal 20, and includes a public key e2 assigned to the store terminal 20. The private key data 24b is data indicating a private key d2 assigned by the authentication device 30 to the store terminal 20.

[0082] The authentication device public key data 24c is data indicating a public key e3 assigned to the authentication device 30. The authentication data 24d is data used in terminal authentication with the authentication device 30 and mutual authentication with the user terminal 10. The authentication data 24d stores a random number generated each time authentication is performed.

[0083] The control unit 25 is a control unit that performs overall control of the store terminal 20, and has a key management unit 25a, a communication control unit 25b, a terminal authentication control unit 25c, a mutual authentication control unit 25d, an electronic signature processing unit 25e, a restoration conversion processing unit 25f, a decryption processing unit 25g, a payment processing unit 25h, a code reading unit 25i, a relay unit 25j, and a judgment unit 25k. In practice, programs corresponding to these functional units are stored in a non-volatile memory such as a ROM (not shown), and these programs are loaded into the CPU and executed, thereby causing the key management unit 25a, the communication control unit 25b, the terminal authentication control unit 25c, the mutual authentication control unit 25d, the electronic signature processing unit 25e, the restoration conversion processing unit 25f, the decryption processing unit 25g, the payment processing unit 25h, the code reading unit 25i, the relay unit 25j, and the judgment unit 25k to execute processes corresponding thereto.

[0084] The key management unit 25a is a processing unit that manages the electronic certificate data 24a, the secret key data 24b, and the authentication device public key data 24c. When the key management unit 25a receives the electronic certificate issued by the authentication device 30, the assigned secret key, and the public key of the authentication device 30, the key management unit 25a stores them in the electronic certificate data 24a, the secret key data 24b, and the authentication device public key data 24c, respectively.

[0085] The communication control unit 25b is a processing unit that controls wireless communication provided by a communication carrier, Wi-Fi (registered trademark) communication, and short-distance wireless communication such as BLUETOOTH (registered trademark).

[0086] The terminal authentication control unit 25c is a processing unit that controls terminal authentication with the authentication device 30. If the terminal authentication control unit 25c is capable of communicating with the authentication device 30, it generates a random number, stores the random number in the authentication data 24d, and performs terminal authentication with the authentication device 30 by using the private key data 24b, the authentication device public key data 24c, and the authentication data 24d.

[0087] The mutual authentication control unit 25d is a processing unit that controls mutual authentication with other terminal devices. The mutual authentication control unit 25d notifies each other of electronic certificates including their public keys with other terminal devices that can communicate with each other by short-distance wireless communication such as BLUETOOTH (registered trademark). For example, if the other connected terminal device is the user terminal 10, the public key e1 is stored in the store terminal 20 and the public key e2 is stored in the user terminal 10 by mutually notifying the electronic certificates.

[0088] In addition, the mutual authentication control unit 25d generates a random number and stores it in the authentication data 24d, and performs mutual authentication with the other connected terminal device using the private key data 24b, a public key (e.g., public key e1) received from the other connected terminal device, and the authentication data 24d.

[0089] The electronic signature processing unit 25e is a processing unit that performs an electronic signature using a private key. The electronic signature processing unit 25e performs an electronic signature on the data to be electronically signed using the private key data 24b, and generates signature data. For example, if the private key data 24b is "d2" and the data to be electronically signed is M2, S2=M2^d2 mod n (4 formulas) The signature data S2 is generated by:

[0090] The restoration conversion processing unit 25f is a processing unit that performs restoration conversion of the electronic signature using a public key. The restoration conversion processing unit 25f performs restoration conversion on the signature data using a public key (e.g., public key e1) corresponding to the private key used in the electronic signature, and restores the data before the electronic signature was performed. Specifically, if the data to be restored is M2, the signature data is S2, and the public key is e1, M2=S2^e1 mod n (5 equations) The data to be restored is restored and converted.

[0091] The decryption processing unit 25g is a processing unit that decrypts the encrypted data encrypted with the public key assigned to the store terminal 20. If the private key data 24b is d2, the encrypted data is C, and the signature data is S2, then S2=C^d2 mod n (6 equations) The signature data S2 is generated by:

[0092] The settlement processing unit 25h is a processing unit that performs settlement of transactions with other terminal devices. The settlement processing unit 25h performs settlement processing with a settlement agency center (not shown) based on the settlement information received from the code reading unit 25i for the transaction contents accepted from the operation display unit 21, etc.

[0093] The code reader 25i is a processing unit that restores payment information from information encoded in a two-dimensional code. The code reader 25i reads a two-dimensional code displayed on another terminal device using the camera 22 and converts it into encrypted data. Such conversion from a two-dimensional code to data is a well-known technique, so a detailed description thereof will be omitted here.

[0094] The code reading unit 25i passes the converted encrypted data to the decryption processing unit 25g, and receives signature data decrypted using the encrypted data from the decryption processing unit 25g. The code reading unit 25i passes the received signature data to the restoration conversion processing unit 25f, and receives payment information restored using the signature data from the restoration conversion processing unit 25f. The code reading unit 25i passes the received payment information to the code reading unit 25i.

[0095] The relay unit 25j is a processing unit that relays information related to a relay request for terminal authentication when the relay unit 25j receives the request from another terminal device to relay the information. The relay unit 25j relays the transmission and reception of information related to server authentication and client authentication performed between the other terminal device and the authentication device 30. Specifically, the relay unit 25j relays notifications between the other terminal device and the authentication device 30, which correspond to the notification of signature data g2 (S12), the notification of signature data g2' (S15), the notification of signature data g3 (S22), and the notification of signature data g3' (S25) shown in FIG. 2.

[0096] The determination unit 25k is a processing unit that receives the authentication result related to the relayed terminal authentication and determines whether or not the transaction is permitted. The determination unit 25k receives the authentication result of the terminal authentication relayed by the relay unit 25j from the authentication device 30, and allows the payment processing by the payment processing unit 25h if the authentication result is valid, and does not allow the payment processing by the payment processing unit 25h if the authentication result is invalid.

[0097] Next, a description will be given of an example of data stored in the storage unit 24 of the store terminal 20 shown in Fig. 5. Fig. 6 is a diagram showing an example of the electronic certificate data 24a, the private key data 24b, the authentication device public key data 24c, and the authentication data 24d shown in Fig. 5.

[0098] As shown in FIG. 6(a), the electronic certificate data 24a indicates that the certificate authority of the electronic certificate issued by the authentication device 30 is "zxcvbnm2345678" and the public key is "bcdefgh0123456."

[0099] As shown in Fig. 6(b), the private key data 24b indicates that the private key is "cdefghi9012345". Also, as shown in Fig. 6(c), the authentication device public key data 24c indicates that the authentication device public key is "poiuytr4567890". Also, as shown in Fig. 6(d), the authentication data 24d indicates that the authentication data is "y8kc9waf2m3".

[0100] <Configuration of authentication device 30> Next, a description will be given of the configuration of the authentication device 30 shown in Fig. 1. Fig. 7 is a diagram showing the configuration of the authentication device 30 shown in Fig. 1. As shown in Fig. 7, the authentication device 30 has a display unit 31, an input unit 32, a communication unit 33, a storage unit 34, and a control unit 35.

[0101] The display unit 31 is a display device such as a liquid crystal panel or a display device. The input unit 32 is an input device such as a keyboard or a mouse. The communication unit 33 is an interface unit for performing data communication with the user terminal 10 etc. via a wireless communication network.

[0102] The storage unit 34 is a storage device including a hard disk drive, a non-volatile memory, etc. The storage unit 34 stores private key data 34a, registration terminal public key data 34b, and authentication data 34c.

[0103] The private key data 34a is data indicating a private key d3 assigned to the authentication device 30. The registered terminal public key data 34b is data indicating a public key assigned to a terminal device registered in the authentication device 30. The authentication data 34c is data used in terminal authentication with a terminal device. The authentication data 34c stores a random number generated each time authentication is performed.

[0104] The control unit 35 is a control unit that performs overall control of the authentication device 30, and has a key management unit 35a, a terminal authentication control unit 35b, an electronic signature processing unit 35c, a restoration conversion processing unit 35d, and a notification unit 35e. In practice, programs corresponding to these functional units are stored in a non-volatile memory such as a ROM (not shown), and these programs are loaded into and executed by the CPU, thereby causing the key management unit 35a, the terminal authentication control unit 35b, the electronic signature processing unit 35c, the restoration conversion processing unit 35d, and the notification unit 35e to execute processes corresponding thereto.

[0105] The key management unit 35a is a processing unit that issues electronic certificates and the like related to terminal devices and manages secret key data 34a and registered terminal public key data 34b. The key management unit 35a assigns public keys and secret keys related to registered terminal devices and issues electronic certificates. The key management unit 35a stores the secret key assigned to the authentication device 30 and the public key assigned to the registered terminal device in the secret key data 34a and registered terminal public key data 34b, respectively.

[0106] The terminal authentication control unit 35b is a processing unit that controls terminal authentication with a terminal device. When the terminal authentication control unit 35b receives information related to terminal authentication from a terminal device, the terminal authentication control unit 35b generates a random number, stores it in authentication data 34c, and performs terminal authentication with the terminal device using the private key data 34a, the registered terminal public key data 34b, and the authentication data 34c.

[0107] The electronic signature processing unit 35c is a processing unit that performs electronic signature using a private key. The electronic signature processing unit 35c performs electronic signature on the data to be electronically signed using the private key data 34a, and generates signature data. For example, if the private key data 34a is "d3" and the data to be electronically signed is M3, S3=M3^d3 mod n (7 equations) The signature data S3 is generated by

[0108] The restoration conversion processing unit 35d is a processing unit that performs restoration conversion of the electronic signature using a public key. The restoration conversion processing unit 35d performs restoration conversion on the signature data using a public key (e.g., public key e1) corresponding to the private key used in the electronic signature, and restores the data before the electronic signature was applied. Specifically, if the data to be restored is M3, the signature data is S3, and the public key is e1, then M3=S3^e1 mod n (8 equations) The data to be restored is restored and converted.

[0109] The notification unit 35e is a processing unit that notifies a terminal authentication result. When information related to terminal authentication is relayed by a terminal device other than the terminal device that is the target of the terminal authentication, the notification unit 35e notifies the relaying terminal device of the authentication result of the terminal authentication performed by the terminal authentication control unit 35b.

[0110] Next, a description will be given of an example of data stored in the storage unit 34 of the authentication device 30 shown in Fig. 7. Fig. 8 is a diagram showing an example of the private key data 34a, the registration terminal public key data 34b, and the authentication data 34c shown in Fig. 7.

[0111] As shown in Fig. 8(a), private key data 34a indicates that the private key is "ujygwsm5784219". Also, as shown in Fig. 8(b), registration terminal public key data 34b indicates that the public key of the user terminal is "qwertyu3456789" and the public key of the store terminal is "bcdefgh0123456". Also, as shown in Fig. 8(c), authentication data 34c indicates that the authentication data is "u17kcx67ws3".

[0112] Next, the procedure of terminal authentication according to this embodiment will be described. Fig. 9 is a flowchart showing the procedure of terminal authentication according to this embodiment. First, if the user terminal 10 and the store terminal 20 are capable of communicating with each other, the user terminal 10, which is offline with the authentication device 30, notifies the store terminal 20 of the electronic certificate data 14a (step S101).

[0113] After receiving the electronic certificate data of the user terminal 10 (step S102), the store terminal 20 notifies the user terminal 10 of the electronic certificate data 24a (step S103).

[0114] When the user terminal 10 receives the electronic certificate data of the store terminal 20 (step S104), the user terminal 10 stores the public key e2 of the store terminal 20, and the store terminal 20 stores the public key e1 of the user terminal 10.

[0115] The user terminal 10 and the store terminal 20 perform mutual authentication using the public key and private key stored therein (step S105). Specifically, the mutual authentication is performed as shown in FIG.

[0116] Next, the user terminal 10 notifies the store terminal 20 of a request to relay the terminal authentication by the authentication device 30 (step S106). The store terminal 20 relays information related to the terminal authentication requested by the user terminal 10 between the user terminal 10 and the authentication device 30 (step S107).

[0117] The authentication device 30 receives information related to terminal authentication of the user terminal 10 from the store terminal 20 (step S108), and performs terminal authentication of the user terminal 10 (step S109). Specifically, as shown in Fig. 2, the user terminal 10 and the authentication device 30 perform server authentication and client authentication with each other to perform terminal authentication, and the store terminal 20 relays information related to terminal authentication transmitted and received during that time.

[0118] The authentication device 30 notifies the store terminal 20 of the authentication result of the terminal authentication of the user terminal 10 (step S110). The store terminal 20 receives the authentication result of the terminal authentication of the user terminal 10 (step S111), and if the authentication result is invalid (step S112; No), ends the process. If the authentication result is valid (step S112; Yes), a transaction is started between the user terminal 10 and the store terminal 20 (step S113).

[0119] As described above, in the authentication system according to this embodiment, when the user terminal 10 is offline with the authentication device 30 and the store terminal 20 is online with the authentication device 30, if the user terminal 10 and the store terminal 20 are capable of communicating with each other via short-range wireless communication, the store terminal 20 is configured to relay information required for terminal authentication between the user terminal 10 and the authentication device 30. As a result, even if the user terminal 10 is offline with the authentication device 30, the user terminal 10 can receive terminal authentication by the authentication device 30 via the store terminal 20.

[0120] In this embodiment, a case is shown in which the user terminal 10 is offline with the authentication device 30 and the store terminal 20 is online with the authentication device 30, but the present invention is not limited to this and can also be applied to a case in which the user terminal 10 is online with the authentication device 30 and the store terminal 20 is offline with the authentication device 30.

[0121] In addition, in the present embodiment, a case has been shown in which the user terminal 10 is offline with the authentication device 30 and the store terminal 20 is online with the authentication device 30, but the present invention is not limited to this and can also be applied to a case in which both the user terminal 10 and the store terminal 20 are offline with the authentication device 30. In this case, a limit can also be set on the processing amount of the payment process.

[0122] In addition, in the present embodiment, the user terminal 10 and the store terminal 20 are described as mobile communication terminal devices, but the present invention is not limited to this, and can also be applied to a case where the user terminal 10 is a smartphone with a card registered as a wallet in an app, and the store terminal 20 is a reader / writer. Note that the user terminal 10 and the store terminal 20 can also be other terminal devices such as a notebook computer.

[0123] In addition, each configuration illustrated in the above embodiment is merely a functional schematic, and does not necessarily have to be physically configured as illustrated. In other words, the form of distribution and integration of each device is not limited to that illustrated, and all or part of the devices can be functionally or physically distributed and integrated in any unit according to various loads, usage conditions, etc. [Industrial Applicability]

[0124] The authentication system and authentication method according to the present invention are useful for efficiently performing terminal authentication when a user's mobile terminal or a store's terminal is offline. [Explanation of symbols]

[0125] 10 User terminal 11 Operation display section 13. Communications Department 14 Storage section 14a Electronic certificate data 14b Private key data 14c Authentication device public key data 14d Authentication data 14e Payment information data 15 Control section 15a Key management section 15b Communication control section 15c Terminal authentication control unit 15d Mutual authentication control section 15e Electronic signature processing section 15f Restoration conversion processing section 15g Encryption processing section 15h Encoding processing section 15i Display control unit 20 Store terminals 21 Operation display section 22 Camera 23 Communications Department 24 Memory section 24a Electronic certificate data 24b Private key data 24c Authentication device public key data 24d Authentication Data 25 Control Unit 25a Key management section 25b Communication control section 25c Terminal authentication control unit 25d Mutual authentication control section 25e Electronic signature processing unit 25f Restoration conversion processing section 25g Decryption processing unit 25h Payment processing section 25i Code reader 25j Relay section 25k judgment part 30 Authentication Device 31 Display section 32 Input section 33 Communications Department 34 Storage section 34a Private key data 34b Registered terminal public key data 34c Authentication data 35 Control section 35a Key management section 35b Terminal authentication control unit 35c Electronic signature processing unit 35d Restoration conversion processing section 35e Notification section

Claims

1. An authentication system having a first terminal carried by a first user, a second terminal carried by a second user, and an authentication device that authenticates the first terminal and the second terminal, a state determination means for determining whether the first terminal is in a state where communication with the authentication device is possible, and a relay request means for requesting the second terminal to relay authentication information when the state determination means determines that the first terminal is in a state where communication with the authentication device is impossible, the second terminal comprises an authentication information relay means for relaying authentication information requested from the first terminal to the authentication device, and a determination means for determining that a payment transaction is possible through a predetermined payment system if the second terminal receives from the authentication device an authentication result indicating that the first terminal is legitimate, and for determining that the payment transaction is not possible through the payment system if the second terminal receives from the authentication device an authentication result indicating that the first terminal is not legitimate; The authentication device includes an authentication processing means for performing authentication processing of the first terminal based on the authentication information, and an authentication result notifying means for notifying the second terminal of an authentication result by the authentication processing means.

1. An authentication system comprising:

2. The relay request means is When a relay request is received from the second terminal, a request is made to the second terminal to relay authentication information.

2. The authentication system according to claim 1 .

3. The first terminal comprises: A storage means for storing a secret key and predetermined authentication data assigned to the device itself; an encryption means for generating authentication information by encrypting the authentication data stored in the storage means with the private key, The authentication device includes:

3. The authentication system according to claim 1, further comprising a decryption unit for decrypting the authentication information with a public key assigned to the first terminal.

4. An authentication system having a portable terminal in which a card possessed by a first user is registered, a reader / writer possessed by a second user, and an authentication device for authenticating the portable terminal and the reader / writer, the portable terminal comprises a state determination means for determining whether or not the portable terminal is in a state capable of communicating with the authentication device, and a relay request means for requesting the reader / writer to relay authentication information when the state determination means determines that the portable terminal is in a state in which communication is not possible; the reader / writer includes an authentication information relay unit that relays authentication information requested from the portable terminal to the authentication device, The authentication device includes an authentication processing means for performing authentication processing of the mobile terminal based on the authentication information.

1. An authentication system comprising:

5. 1. An authentication method in an authentication system having a first terminal carried by a first user, a second terminal carried by a second user, and an authentication device that authenticates the first terminal and the second terminal, comprising: a state determination step of determining whether the first terminal is in a state capable of communicating with the authentication device; a relay request step of requesting the second terminal to relay authentication information when the first terminal is determined to be in a communication-disabled state by the state determination step; an authentication information relay step of the second terminal relaying authentication information requested from the first terminal to the authentication device; an authentication processing step in which the authentication device performs authentication processing of the first terminal based on the authentication information; an authentication result notifying step in which the authentication device notifies the second terminal of an authentication result obtained by the authentication processing step; a determining step of determining that a payment transaction through a predetermined payment system is possible if the second terminal receives from the authentication device an authentication result indicating that the first terminal is legitimate, and determining that the payment transaction through the payment system is not possible if the second terminal receives from the authentication device an authentication result indicating that the first terminal is not legitimate; 13. An authentication method comprising:

Images