JP2008011100A - Attribute authentication method, attribute certificate generating apparatus, service provision destination apparatus, service provision source apparatus, and attribute authentication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an attribute authentication method, attribute certificate generating apparatus, service provision destination apparatus, service provision source apparatus, and attribute authentication system, which are capable of preventing an apparatus of a service provision destination from consuming a huge amount of memory capacities to store a plurality of attribute certificates. <P>SOLUTION: An attribute certificate issue apparatus 10 encrypts attribute information by using a different encryption key by each of attribute information groups. The attribute certificate issue apparatus 10 issues an attribute certificate described with the encrypted attribute information. A user terminal 30 generates an encrypted decryption key by encrypting a decryption key corresponding to the encryption key through the use of a public key of servers 40A, 40B. The user terminal 30 transmits the encrypted decryption key and the attribute certificate to the servers 40A, 40B. The servers 40A, 40B use private keys of their own servers to decrypt the decryption key from the encrypted decryption key. The servers 40A, 40B decrypts the attribute certificate by using the decryption key to acquire the attribute information of the group corresponding to the decryption key. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an attribute authentication method, an attribute certificate generating device, a service providing destination device, a service providing source device, and an attribute authentication system.

Conventionally, a server providing a service such as distribution of predetermined data or permission to connect to a predetermined website uses the attribute certificate in which the personal information of the service user is described, and the identity of the service user A technique of performing authentication or the like is known (see, for example, Patent Document 1). In addition, since various types of information described in attribute certificates are mostly related to the privacy of service users, for example, encryption is generally performed to protect the information from being leaked to the outside. .
JP 2004-304227 A

  By the way, the attribute certificate is issued for each server of the service provider that performs the personal authentication, for example, according to each use. Therefore, a device such as a mobile terminal on the service user side needs to store all of a plurality of attribute certificates issued for each server in order to use a service from each server. However, there are many cases where the storage capacity of a device on the service user side, such as a mobile phone, is often limited, and it may be difficult to secure a large memory capacity enough to store a plurality of attribute certificates.

  Therefore, the present invention has been made in view of the above, and an attribute authentication method and an attribute certificate generation apparatus that can prevent a service providing destination apparatus from consuming a large amount of memory for storing a plurality of attribute certificates. An object of the present invention is to provide a service providing destination device, a service providing source device, and an attribute authentication system.

  In order to solve the above-described problem, the attribute authentication method of the present invention groups attribute information when the attribute certificate generation device generates an attribute certificate including a plurality of attribute information, A first step of encrypting a plurality of attribute information with different encryption keys for each of the grouped groups, and the service providing destination device uses the public key of the service providing source device as a decryption key corresponding to the encryption key in the first step A second step of encrypting and generating an encryption / decryption key, an encryption / decryption key generated by the service providing destination device in the second step, and an attribute certificate generated by the attribute certificate generating device in the first step A third step of transmitting the certificate to the service providing source device, and the service providing source device using its own secret key from the encryption / decryption key transmitted from the service providing destination device in the third step A fourth step of decrypting the decryption key, and the service providing source device decrypting the attribute certificate transmitted from the service providing destination device in the third step with the decryption key decrypted in the fourth step. And a fifth step of acquiring attribute information grouped corresponding to.

  In addition, when generating an attribute certificate including a plurality of attribute information, the attribute certificate generation apparatus groups the plurality of attribute information, and uses a plurality of attributes with different encryption keys for each of the grouped groups. Encrypt information.

  Further, the service providing destination device generates a decryption key corresponding to an encryption key different for each group of attribute information with a public key of the service providing source device to generate an encrypted decryption key, and a generation unit generates An encryption / decryption key, and a transmission unit that transmits the attribute certificate generated by the attribute certificate generation device to the service provider device.

  In addition, the service provider apparatus obtains the private key of its own device from the encryption / decryption key generated by encrypting the decryption key corresponding to the encryption key different for each group of attribute information with the public key of its own device. And decryption means for decrypting the decryption key, and attribute information grouped corresponding to the decryption key by decrypting the attribute certificate transmitted from the service providing destination device with the decryption key decrypted by the decryption key decryption means Acquisition means for acquiring.

  The attribute authentication system includes the attribute certificate generation device, the service providing destination device, and the service providing source device.

  According to the attribute authentication method, the attribute certificate generation device, the service providing destination device, the service providing source device, and the attribute authentication system of the present invention, the attribute information is encrypted with a different encryption key for each group to which the attribute information belongs. Encrypted. In other words, the attribute information is encrypted for each group of attribute information necessary when, for example, a certain service providing apparatus performs personal authentication for a service providing destination user according to each application. A plurality of groups of attribute information encrypted with different encryption keys are included in one attribute certificate.

  On the other hand, a service providing source device receives the attribute certificate and the encryption / decryption key for the own device from the service providing destination device. Since the encryption / decryption key for the own device is encrypted with the public key of the own device, the service providing source device uses the private key of the own device to decrypt the decryption key from the encryption / decryption key. be able to. Then, the service providing source device can decrypt and read only the group attribute information that can be decrypted with the decryption key, among the plurality of groups of attribute information described in the attribute certificate. On the other hand, for example, when a certain service provider device acquires an encryption / decryption key for another device, the service provider device does not know the secret key of the other device. The decryption key for another device encrypted with the public key of the other device cannot be decrypted. Therefore, it is possible to prevent the service providing source device from reading the attribute information for another device among the plurality of attribute information included in the attribute certificate.

  As described above, even if one attribute certificate is shared between different service provider devices, a service provider device cannot read attribute information for other devices. In other words, the attribute certificate generating device only needs to generate one attribute certificate for one service providing destination device regardless of the number of devices that provide services to one service providing destination device. In other words, even if one service providing destination device is provided with services from a plurality of service providing source devices, it is only necessary to hold one attribute certificate. In this case, each service providing device reads only the attribute information for its own device and does not authenticate itself without reading the attribute information for other devices. Therefore, it is possible to prevent the service providing destination device from consuming a large amount of memory in order to store, for example, a plurality of attribute certificates corresponding to the number of service providing source devices.

  According to the present invention, a certain service provider device cannot read attribute information for other devices. For this reason, the service providing destination device only needs to hold one attribute certificate when services are provided from a plurality of service providing source devices, for example. Accordingly, it is possible to prevent the service providing destination device from consuming a large amount of memory in order to store a plurality of attribute certificates corresponding to the number of the plurality of service providing source devices.

  Exemplary embodiments of an attribute certificate generating device, a service providing destination device, a service providing source device, an attribute authentication system, and an attribute authentication method according to the present invention will be described below in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  First, a basic configuration of the attribute authentication system 1 according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of the attribute authentication system 1. As shown in FIG. 1, an attribute authentication system 1 includes an attribute certificate issuing device (attribute certificate generating device) 10, a public key management device 20, a user terminal (service providing destination device) 30, and a server (service providing source device). 40. In FIG. 1, the user terminal 30 and the server 40 are illustrated as a single unit, but in the actual configuration of the attribute authentication system 1, there are a plurality of user terminals 30 and servers 40. The attribute certificate issuing device 10 is installed in, for example, an attribute certificate issuing authority (AA), and the public key management device 20 is installed in, for example, a certificate authority (CA) that issues public keys. It is. Hereinafter, each component of the attribute authentication system 1 will be described in detail.

  The attribute certificate issuing device 10 is a device that issues an attribute certificate. FIG. 2 is a hardware configuration diagram of the attribute certificate issuing device 10. As shown in FIG. 2, the attribute certificate issuing device 10 physically includes a CPU 11, a RAM 12 and a ROM 13 that are main storage devices, an input device 14 such as a keyboard and a mouse that are input devices, and an output device 15 such as a display. The computer system includes a communication module 16 that is a data transmission / reception device such as a network card, and an auxiliary storage device 17 such as a hard disk. Each function of the attribute certificate issuing device 10 to be described later is configured to read predetermined software on hardware such as the CPU 11 and the RAM 12 shown in FIG. 2 to control the communication module 16, the input device 14, This is realized by operating the output device 15 and reading and writing data in the RAM 12 and the auxiliary storage device 17.

  Returning to FIG. 1, the attribute certificate issuing device 10 is configured to be able to communicate with the user terminal 30 via the communication network 50. The communication network 50 is a wireless communication network such as the Internet network, a PDC (Personal Digital Cellular) network, and an IMT (International Mobile Telecommunication) 2000 network.

  The attribute certificate issuing device 10 functionally includes an attribute classification table storage unit 110, an attribute information encryption unit 120, and an attribute certificate issue unit 130. The attribute classification table storage unit 110 stores an attribute classification table that is referred to when the attribute information encryption unit 120 groups and encrypts a plurality of attribute information according to each use. In the present embodiment, the attribute information is classified for each group of attribute information necessary when performing personal authentication for a user of a service providing destination with a server of a certain service providing source.

  FIG. 3 is a diagram illustrating an example of the attribute classification table stored in the attribute classification table storage unit 110. In FIG. 3, each attribute information is classified for each group of attribute information necessary for each server to authenticate the user of the user terminal 30. That is, the attribute information used when the server 40A authenticates the user of the user terminal 30 is “user identification information”, and “user identification information” is classified into group A. Similarly, “user identification information” and “charging information” used by the server 40B are classified into group B, and “charging information” and “affiliation information” used by the server 40C are classified into group C. Further, “user identification information”, “billing information”, and “affiliation information” used by the server 40D are classified into a group D. As described above, at least one attribute information belongs to each group. In addition, for example, one attribute information such as “user identification information” may belong to a plurality of groups. Note that the above-described classification (affiliation relationship between attribute information and group) is the same in the following description.

  Returning to FIG. 1, the attribute information encryption unit 120 encrypts the attribute information with a different encryption key for each group to which the attribute information belongs. The attribute information encryption unit 120 refers to the attribute classification table stored in the attribute classification table storage unit 110 to know to which group certain attribute information belongs. FIG. 4 is a diagram showing an encryption key used for the encryption process of the attribute information encryption unit 120. As shown in FIG. 4, the attribute information encryption unit 120 encrypts attribute information (user identification information) belonging to the group A with the encryption key A. Similarly, the attribute information encryption unit 120 encrypts attribute information (user identification information and charging information) belonging to the group B with the encryption key B, and converts attribute information (charging information and membership information) belonging to the group C to the encryption key C. And the attribute information (user identification information, billing information and affiliation information) belonging to group D is encrypted with the encryption key D. The attribute information belonging to a plurality of groups is encrypted with the encryption keys of the plurality of groups, but is encrypted so that it can be decrypted with a decryption key corresponding to any one of the encryption keys. That is, the “affiliation information” belonging to both the group C and the group D is encrypted with the encryption key C and the encryption key D, but the decryption corresponding to either the encryption key C or the encryption key D is performed. Can be decrypted with a key. Returning to FIG. 1, the attribute information encryption unit 120 outputs the attribute information thus encrypted and the encryption key used for encryption of each attribute information to the attribute certificate issuing unit 130.

  The attribute certificate issuance unit 130 receives encrypted attribute information from the attribute information encryption unit 120 and generates an attribute certificate describing the encrypted attribute information. The attribute certificate issuing unit 130 issues the generated attribute certificate to the user terminal 30 via the communication network 50. This issuance processing is performed by transmitting attribute certificate electronic data from the attribute certificate issuing device 10 to the user terminal 30. Further, the attribute certificate issuing unit 130 receives the encryption key used for encrypting each attribute information from the attribute information encryption unit 120 and transmits it to the user terminal 30 via the communication network 50.

  The public key management device 20 is a device that manages the public key of the server 40. As with the attribute certificate issuing device 10, the public key management device 20 is configured as a computer system including CPU, RAM, ROM, input device, output device, communication module, auxiliary storage device, and the like as physical components. (See FIG. 2). The public key management device 20 is configured to be able to communicate with the user terminal 30 via the communication network 50.

  The public key management device 20 functionally includes a public key storage unit 210 and a public key transmission unit 220. The public key storage unit 210 stores, for example, the public key of the server 40 acquired in advance from the server 40. The public key transmission unit 220 transmits the public key of the server 40 stored in the public key storage unit 210 to the user terminal 30.

  The user terminal 30 is a device such as a mobile terminal as a service providing destination, and is, for example, a mobile phone in the present embodiment. FIG. 5 is a hardware configuration diagram of the user terminal 30. As shown in FIG. 5, the user terminal 30 physically includes a CPU 31, a RAM 32 and a ROM 33 that are main storage devices, an operation unit 34 such as an operation button, an LCD (Liquid Crystal Display), an EL (Electro Luminescence), and the like. The output device 35, the attribute certificate issuing device 10, the public key management device 20, and the server 40 are configured to include a wireless communication unit 36 that wirelessly transmits and receives data and an auxiliary storage device 37 such as a memory device. Each function of the user terminal 30, which will be described later, has an operation unit 34, an output device 35, and a wireless communication unit under the control of the CPU 31 by reading predetermined software on hardware such as the CPU 31 and the RAM 32 shown in FIG. This is realized by operating 36 and reading and writing data in the RAM 32 and the auxiliary storage device 37. In addition, the RAM 32 and the auxiliary storage device 37 of the user terminal 30 are limited in their storable capacities, and it is difficult to ensure a large memory capacity enough to store a plurality of attribute certificates, for example.

  Returning to FIG. 1, the user terminal 30 is configured to be able to communicate with the attribute certificate issuing device 10 and the public key management device 20 via the communication network 50. Further, the user terminal 30 is configured to be able to communicate with the server 40 via the communication network 60. Similar to the communication network 50, the communication network 60 is a wireless communication network such as the Internet network, the PDC network, and the IMT2000 network.

  Functionally, the user terminal 30 includes a reception unit 310, an encryption / decryption key generation unit (generation unit) 320, a service request unit (transmission unit) 330, and a service transfer unit 340. The receiving unit 310 receives the attribute certificate issued by the attribute certificate issuing device 10 via the communication network 50. The receiving unit 310 receives the encryption key used when the attribute certificate issuing device 10 encrypts each attribute information from the attribute certificate issuing device 10. In addition, the receiving unit 310 acquires the public key of the server 40 from the public key management device 20. The receiving unit 310 outputs the encryption key acquired from the attribute certificate issuing device 10 and the public key acquired from the public key management device 20 to the encryption / decryption key generation unit 320. Further, the reception unit 310 outputs the attribute certificate acquired from the attribute certificate issuing device 10 to the service request unit 330.

  The encryption / decryption key generation unit 320 receives the encryption key and public key from the reception unit 310, and is a public key of a server that refers to attribute information encrypted with an arbitrary encryption key. The decryption key corresponding to the encryption key The encryption / decryption key is generated by encrypting. FIG. 6 is a diagram showing the public key used for the encryption / decryption key generation process of the encryption / decryption key generation unit 320, the encryption / decryption key generated by the encryption / decryption key generation process, and the like. As shown in FIG. 6, the encryption / decryption key generating unit 320 uses the decryption key A corresponding to the encryption key A (the encryption key used when encrypting the attribute information for the server 40A) as the public key of the server 40A. To generate an encryption / decryption key A. Similarly, the encryption / decryption key generation unit 320 generates the encryption / decryption key B by encrypting the decryption key B with the public key of the server 40B, and encrypts / decrypts the decryption key C with the public key of the server 40C. A key C is generated, and the decryption key D is encrypted with the public key of the server 40D to generate the encrypted decryption key D. In the present embodiment, an arbitrary encryption key and a decryption key corresponding to the encryption key are the same. Returning to FIG. 1, the encryption / decryption key generation unit 320 outputs the encryption / decryption key thus generated by encryption to the service request unit 330.

  The service request unit 330 requests a service such as distribution of predetermined data or permission for connection to a predetermined website from the server 40 via the communication network 60. In order for the user terminal 30 to receive the service from the server 40, the user terminal 30 needs to cause the server 40 to authenticate the identity of the user of the terminal itself. Therefore, the service request unit 330 transmits a request signal for the service to the server 40, and the attribute certificate input from the reception unit 310 and the encryption / decryption key generation unit 320 are the public key of the server 40. The encrypted decryption key obtained by encrypting the decryption key corresponding to the server encryption key is transmitted to the server 40.

  The service transfer / reception unit 340 accepts the provision of service from the server 40 as a response signal to the service request signal or the like transmitted from the service request unit 330 to the server 40.

  The server 40 is a service provider server. The server 40 is a computer system that includes a CPU, RAM, ROM, input device, output device, communication module, auxiliary storage device, and the like as physical components, similar to the attribute certificate issuing device 10 and the public key management device 20. (See FIG. 2). The server 40 is configured to be able to communicate with the user terminal 30 via the communication network 60.

  Functionally, the server 40 includes a reception unit 410, a decryption key decryption unit (decryption unit) 420, a secret key storage unit 430, an attribute information acquisition unit (acquisition unit) 440, and a service provision unit 450. The receiving unit 410 receives a service request signal from the user terminal 30 via the communication network 60, and further receives an attribute certificate and an encryption / decryption key to confirm the identity of the user of the user terminal 30. To do. The receiving unit 410 outputs the encryption / decryption key received from the user terminal 30 to the decryption key / decryption unit 420. In addition, the reception unit 410 outputs the attribute certificate received from the user terminal 30 to the attribute information acquisition unit 440. Further, the receiving unit 410 outputs the service request signal received from the user terminal 30 to the service providing unit 450.

  The decryption key decryption unit 420 receives the encryption / decryption key from the reception unit 410 and decrypts the decryption key encrypted with the encryption / decryption key. At this time, the decryption key decryption unit 420 decrypts the decryption key using the private key of the own server stored in the private key storage unit 430. As described above, an arbitrary encryption / decryption key is a public key of a server that refers to attribute information encrypted with an encryption key corresponding to a decryption key obtained by decrypting the encryption / decryption key. It is encrypted. Therefore, the decryption key decryption unit 420 uses the private key of the local server stored in the private key storage unit 430 to decrypt the decryption key for the local server from the encryption / decryption key for the local server input from the reception unit 410. Can be decrypted.

  For example, in FIG. 6 described above, the server 40A receives the encryption / decryption key A from the user terminal 30, and decrypts the decryption key A from the encryption / decryption key A using the private key of the server itself. The decryption key A is associated with the encryption key A. On the other hand, the server 40A does not receive encryption / decryption keys (for example, encryption / decryption key B) for other servers. Even if the server 40A obtains an encryption / decryption key for another server, the server 40A does not know the secret key of the other server, so the decryption key for other server (for example, the decryption key B) is decrypted. Can not do it. Similarly, the server 40B decrypts the decryption key B from the encryption / decryption key B using the private key of its own server, and the server 40C uses the private key of its server to decrypt the decryption key from the encryption / decryption key C. C is decrypted, and the server 40D decrypts the decryption key D from the encryption / decryption key D using the private key of the server itself. In contrast, each server does not receive the encryption / decryption key for the other server, but even if the server obtains the encryption / decryption key for the other server, each server has the private key of the other server. Cannot be used to decrypt decryption keys for other servers. The decryption key decryption unit 420 outputs the decrypted decryption key for its own server to the attribute information acquisition unit 440.

  The attribute information acquisition unit 440 uses the decryption key input from the decryption key decryption unit 420 to decrypt and read the attribute information described in the attribute certificate input from the reception unit 410. As described above, the attribute information described in the attribute certificate is encrypted with a different encryption key by the attribute certificate issuing device 10 for each group to which each attribute information belongs, that is, for each server that uses each attribute information. Yes. On the other hand, since the decryption key corresponding to the encryption key used when encrypting the attribute information for an arbitrary server is encrypted with the public key of the server, the decryption key and the decryption key decryption of the server The decryption key decrypted with the private key of the server 420 is the same. For this reason, the attribute information acquisition unit 440 can decrypt and read the attribute information for the server described in the attribute certificate using the decryption key input from the decryption key decryption unit 420. The attribute information acquisition unit 440 outputs the read attribute information to the service providing unit 450.

  On the other hand, the decryption key corresponding to the encryption key used when encrypting the attribute information for the other server described in the attribute certificate is the decryption key decrypted by the decryption key decryption unit 420 using the private key of the own server. Different. For this reason, the attribute information acquisition unit 440 cannot decrypt and read the attribute information for other servers described in the attribute certificate using the decryption key input from the decryption key decryption unit 420.

  The service providing unit 450 confirms the identity of the user of the user terminal 30 with reference to the attribute information input from the attribute information acquisition unit 440, and the service request input from the receiving unit 410 according to the confirmation result A service corresponding to the signal is provided to the user terminal 30.

  Next, an operation (attribute authentication method) performed by the attribute authentication system 1 will be described with reference to FIG. FIG. 7 is a sequence diagram showing the operation of the attribute authentication system 1. In FIG. 7, it is assumed that the user terminal 30 receives services from the server 40A and the server 40B.

  First, the attribute certificate issuing device 10 encrypts the attribute information with a different encryption key for each group to which the attribute information belongs. That is, for example, as can be seen with reference to FIGS. 3, 4, and 6 described above, the attribute certificate issuing device 10 encrypts attribute information (user identification information) belonging to the group A with the encryption key A, and the group B Attribute information (user identification information and billing information) belonging to is encrypted with the encryption key B. “User identification information” belonging to both group A and group B is encrypted with the encryption keys (encryption key A and encryption key B) of the two groups. The decryption key (decryption key A and decryption key B) corresponding to one of the encryption keys can be decrypted (step S1).

  Next, the attribute certificate issuing device 10 generates an attribute certificate in which the attribute information encrypted in step S <b> 1 is described, and issues it to the user terminal 30 via the communication network 50. Further, the attribute certificate issuing device 10 transmits the encryption key (encryption key A and encryption key B) used for the encryption process in step S1 to the user terminal 30 (step S2).

  Next, the public key management device 20 transmits the public key acquired in advance from the server 40A and the server 40B to the user terminal 30 (step S3).

  Next, the user terminal 30 generates an encrypted decryption key obtained by encrypting the decryption key corresponding to the encryption key with the public key of the server that uses the attribute information encrypted with an arbitrary encryption key. That is, for example, as can be seen with reference to FIG. 3, FIG. 4 and FIG. 6 described above, the decryption key A is encrypted with the public key of the server 40A that uses the “user identification information” encrypted with the encryption key A. An encryption / decryption key A is generated. Also, an encryption / decryption key B is generated by encrypting the decryption key B with the public key of the server 40B that uses the “user identification information” and “billing information” encrypted with the encryption key B (step S4).

  As mentioned above, step S1-step S4 are operation | movement performed before the portable terminal of a service provision destination requests | requires a service of the server of a service provision source. The attribute certificate issuing device 10, the public key management device 20, and the user terminal 30 perform the operations of Step S1 to Step S4 for the server 40C and the server 40D. On the other hand, an operation performed when the user terminal 30 requests a service from the server 40A and the server 40B will be described below.

  The user terminal 30 requests a service from the server 40A via the communication network 60. The user terminal 30 transmits the service request signal, the attribute certificate issued in step S2, and the encryption / decryption key A generated in step S4 to the server 40A (step S5).

  The server 40A first confirms the identity of the user terminal 30 with respect to the user in order to provide the user terminal 30 with a service corresponding to the service request signal received in step S5. The server 40A decrypts the decryption key A from the encryption / decryption key A received in step S5 with the private key of its own server. In step S4, since the decryption key A is obtained by encrypting the decryption key A with the public key of the server 40A, the server 40A uses the private key of its own server to encrypt the decryption key A from the decryption key A. Can be decrypted (step S6).

  Next, the server 40A uses the decryption key A decrypted in step S6 to decrypt and read “user identification information” described in the attribute certificate received in step S5. In step S1, since the attribute certificate is obtained by encrypting and describing the “user identification information” with the encryption key A, the server 40A can decrypt and read the “user identification information” with the decryption key A. Yes (step S7).

  Next, the server 40A uses the “user identification information” read in Step S7 to confirm the identity of the user terminal 30 with respect to the user (Step S8).

  Next, the server 40A provides a service corresponding to the service request signal received in step S5 to the user terminal 30 (step S9).

  Further, the user terminal 30 requests a service from the server 40B via the communication network 60. The user terminal 30 transmits the service request signal, the attribute certificate issued in step S2, and the encryption / decryption key B generated in step S4 to the server 40B (step S10).

  The server 40B first confirms the identity of the user terminal 30 with respect to the user in order to provide the user terminal 30 with a service corresponding to the service request signal received in step S10. The server 40B decrypts the decryption key B from the encryption / decryption key B received in step S10 with the private key of its own server. In step S4, the decryption key B is obtained by encrypting the decryption key B with the public key of the server 40B. Thus, the server 40B uses the private key of its own server to decrypt the decryption key B from the encryption / decryption key B. Can be decrypted (step S11).

  Next, the server 40B uses the decryption key B decrypted in step S11 to decrypt and read “user identification information” and “billing information” described in the attribute certificate received in step S10. In step S1, since the attribute certificate is obtained by encrypting and describing “user identification information” and “billing information” with the encryption key B, the server 40B uses the decryption key B to identify “user identification information” and “ The “billing information” can be decrypted and read (step S12).

  Next, the server 40B confirms the identity of the user terminal 30 with respect to the user using the “user identification information” and “billing information” read in step S12 (step S13).

  Next, the server 40B provides a service corresponding to the service request signal received in step S10 to the user terminal 30 (step S14).

  Next, operations and effects of the attribute authentication system 1 and the attribute authentication method according to the present embodiment will be described. According to the attribute authentication system 1 and the attribute authentication method of the present embodiment, the attribute information is encrypted with a different encryption key for each group to which the attribute information belongs. That is, the attribute information is encrypted for each group of attribute information required when each server performs personal authentication for the user of the user terminal 30, for example, according to each application. A plurality of groups of attribute information encrypted with different encryption keys are included in one attribute certificate.

  On the other hand, each server receives the attribute certificate and its own server encryption / decryption key from the user terminal 30. Since the encryption / decryption key for the own server is encrypted with the public key of the own server, the server can decrypt the decryption key from the encryption / decryption key using the private key of the own server. it can. The server decrypts and reads only the attribute information of the group that can be decrypted with the decrypted decryption key among the plurality of attribute information described in the attribute certificate. Thus, one encryption / decryption key is transmitted to each server. For this reason, for example, when an encryption / decryption key that is different for each attribute information used by each server is transmitted and received between the user terminal 30 and each server, the communication burden on the user terminal 30 increases, and the user terminal 30 and each server It is possible to prevent the amount of communication during the period from significantly increasing. On the other hand, for example, when a server obtains an encryption / decryption key for another server, the server does not know the secret key of the other server, so the server is encrypted with the public key of the other server. Decryption keys for other servers cannot be decrypted. Therefore, it is possible to prevent the server from reading the attribute information for other servers among the plurality of attribute information described in the attribute certificate.

  As described above, even if one attribute certificate is shared between servers of different service providers, an arbitrary server cannot read attribute information for other servers. In other words, the attribute certificate issuing device 10 only needs to issue one attribute certificate to one service providing destination device regardless of the number of servers that provide services to one service providing destination device. In other words, even if one service providing destination apparatus is provided with services from a plurality of servers, it is only necessary to hold one attribute certificate. In this case, each server does not read the attribute information for other servers, that is, each server does not infringe on the privacy of the user of the service provider, and authenticates itself by reading only the attribute information for its own server. . Therefore, the service providing destination apparatus only needs to secure a memory capacity for holding one attribute certificate. For example, a large number of attribute certificates are stored in order to store a plurality of attribute certificates corresponding to the number of service providing source servers. It is possible to prevent the consumption of the memory.

  As mentioned above, although preferred embodiment of this invention was described, it cannot be overemphasized that this invention is not limited to the said embodiment.

  For example, in the above embodiment, the attribute certificate issuing device 10 performs the attribute information encryption process, but the user terminal 30 may perform the attribute information encryption process. In this case, for example, the attribute authentication system 1 can be configured by including the attribute certificate issuing device 10 in the user terminal 30.

  In the above embodiment, an arbitrary encryption key and a decryption key corresponding to the encryption key are the same, but they may be separate from each other. In this case, the decryption key may be generated by the attribute certificate issuing device 10 or may be generated by the user terminal 30.

1 is a schematic configuration diagram of an attribute authentication system 1. FIG. 2 is a hardware configuration diagram of an attribute certificate issuing device 10. FIG. It is a figure which shows an example of an attribute classification table. It is a figure which shows the encryption key used for the encryption process of attribute information. 2 is a hardware configuration diagram of a user terminal 30. FIG. It is a figure which shows the public key etc. which are used for the production | generation process of an encryption / decryption key. It is a sequence diagram which shows operation | movement of the attribute authentication system 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Attribute authentication system, 10 ... Attribute certificate issuing apparatus, 110 ... Attribute classification table storage part, 120 ... Attribute information encryption part, 130 ... Attribute certificate issue part, 20 ... Public key management apparatus, 210 ... Public key storage , 220 ... public key transmission unit, 30 ... user terminal, 310 ... reception unit, 320 ... encryption / decryption key generation unit, 330 ... service request unit, 340 ... service transfer unit, 40, 40A, 40B, 40C, 40D ... Server: 410: Receiving unit, 420: Decryption key decryption unit, 430: Secret key storage unit, 440: Attribute information acquisition unit, 450 ... Service providing unit, 50, 60 ... Communication network.

Claims (5)

When the attribute certificate generation device generates an attribute certificate including a plurality of attribute information, the plurality of attribute information is grouped, and the plurality of grouped groups are grouped with different encryption keys for the grouped groups. A first step of encrypting attribute information;
A second step in which the service providing destination device generates an encrypted decryption key by encrypting a decryption key corresponding to the encryption key in the first step with the public key of the service providing source device;
The service providing destination device transmits the encryption / decryption key generated in the second step and the attribute certificate generated by the attribute certificate generating device in the first step to the service providing source device. 3 steps,
A fourth step in which the service providing apparatus decrypts the decryption key using the private key of the own apparatus from the encrypted decryption key transmitted from the service provision destination apparatus in the third step;
The service providing source device decrypts the attribute certificate transmitted from the service providing destination device in the third step with the decryption key decrypted in the fourth step, so that a group corresponding to the decryption key is obtained. An attribute authentication method comprising: a fifth step of acquiring attributed attribute information.   When generating an attribute certificate including a plurality of attribute information, the plurality of attribute information is grouped, and the plurality of attribute information is encrypted with different encryption keys for the grouped groups. An attribute certificate generating device characterized by Generating means for encrypting a decryption key corresponding to a different encryption key for each group of attribute information with the public key of the service providing source device, and generating an encrypted decryption key;
A service providing destination device comprising: an encryption / decryption key generated by the generating unit; and a transmitting unit that transmits the attribute certificate generated by the attribute certificate generating device to the service providing source device. Decrypting the decryption key using the private key of the own device from the encryption / decryption key generated by encrypting the decryption key corresponding to the encryption key different for each group of attribute information with the public key of the own device Decryption means;
Obtaining means for obtaining attribute information grouped corresponding to the decryption key by decrypting the attribute certificate transmitted from the service providing destination device with the decryption key decrypted by the decryption key decryption means A service provider device characterized by the above.   An attribute authentication system comprising the attribute certificate generation device according to claim 2, the service provision destination device according to claim 3, and the service provision source device according to claim 4.

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