JP4909626B2 - Attribute authentication system, attribute information anonymization method and program in the same system - Google Patents

Description

  The present invention relates to an attribute authentication system, an attribute information anonymization method and program in the system, and in particular, an attribute authentication system that enables revocation confirmation even when anonymization is performed, an attribute information anonymization method in the system, and Regarding the program.

In recent years, various services have been provided electronically through the Internet. When providing such a service, it is essential to authenticate the user. Here, a method for authenticating a user is generally classified into authentication for specifying an individual and authentication for not specifying an individual such as attribute authentication (for example, see Patent Document 1).
Japanese Patent Publication No. 8-2051

  By the way, in the conventional attribute authentication, the anonymity of attribute information was not considered. In addition, some research for anonymization has been made, but the content is insufficient, and further, communication with a third party is required when performing attribute authentication. For this reason, communication may be observed by a third party, and the behavior of the user may be traced, and a problem relating to privacy protection has been left as a technical issue.

  On the other hand, there has been a problem that revocation confirmation cannot be performed when anonymous authentication is performed in consideration of anonymity of attribute information.

  Therefore, the present invention has been made in view of the above circumstances, guarantees anonymity at the time of attribute authentication, and can perform anonymization without requiring communication with a third party. An object of the present invention is to provide an attribute authentication system that enables revocation confirmation even when anonymous authentication is performed, and a method and program for anonymizing attribute information in the system.

The present invention proposes the following items in order to solve the above-described problems.
(1) The present invention is an attribute authentication system in which a reliable server, a user terminal, a service providing server, and an invalidation verification authority server are connected via a network, wherein the reliable server (for example, , Corresponding to the CA server 3 in FIG. 1), when an attribute certificate issuance request is received from the user terminal, the user certificate is signed with the signature key for the attribute the user has, and the attribute certificate Generating means, and transmitting means for transmitting the generated attribute certificate to the requested user terminal, the user terminal (e.g., corresponding to the user terminal 1 in FIG. 1) providing the service Service provision request transmitting means for transmitting a service provision request to the server; and generating a random number and multiplying the generated random number by the attribute certificate received from the trusted server. Deformed, and a returning means for returning to the service providing server and a computed signature value against challenge information transmitted with the modified attribute certificate from the service providing server, the service providing server (e.g., 1) (corresponding to the SP server 2 in FIG. 1) verifies the validity of the modified attribute certificate and signature value, respectively. Service providing means for providing a service based on the attribute to the user terminal, and the revocation verification station server (e.g., corresponding to the revocation verification station server 4 in FIG. 1) is a secret key transmitted from the user terminal. registration means for registering, at the time of authentication processing, upon receiving the invalidation confirmation request for attribute certificate from the service providing server, revocation probability of the attribute certificate Processing is executed, has proposed an attribute authentication system characterized in that a revocation check processing result returning means for returning the revocation checking processing result of the attribute certificate to the service providing server.

  According to the present invention, when a reliable server receives an attribute certificate issuance request from the user terminal, the trusted server signs the attribute certificate by signing the user's public key with the signature key that the user has. Generating means for generating, and transmitting means for transmitting the generated attribute certificate to the requested user terminal, the user terminal transmitting a service providing request to the service providing server, and a random number Generate and transform the generated random number by multiplying the attribute certificate received from a reliable server, and provide the modified attribute information and the signature value calculated for the challenge information sent from the service providing server A reply means for replying to the server, and the service providing server confirms the validity of the modified attribute certificate and signature value, respectively. And providing a service based on the attribute to the user terminal that requested the service provision, and the revocation verification station server is transmitted from the user terminal. A registration means for registering a secret key, and a revocation confirmation process result reply means for executing a revocation confirmation process when a revocation confirmation request is received from the service providing server during the authentication process and returning a revocation confirmation process result to the service providing server; It has. As a result, anonymity can be guaranteed at the time of attribute authentication and anonymization can be performed without requiring communication with a third party, and revocation confirmation is possible even when anonymous authentication is performed. Become.

  (2) The present invention provides the attribute authentication system according to (1), wherein the reliable server further includes update means for assigning a plurality of signature keys to each attribute and periodically updating the signature key. We propose an attribute authentication system characterized by having it.

  According to the present invention, the reliable server includes update means for assigning a plurality of signature keys to each attribute and periodically updating the signature keys. As a result, the expiration date can be appropriately managed.

(3) In the attribute authentication system according to (1) or (2), the present invention provides the revocation verification authority server (for example, corresponding to the revocation verification authority server 4 in FIG. 1) from the service providing server to the challenge. Receiving a random number and a signature value transmitted as information , calculating a signature value of the received random number for the secret key registered in the registration means, and whether the calculated signature value matches the received signature value It proposes an attribute authentication system and executes the Kaniyori the revocation confirmation process.

  According to this invention, the revocation verification station server receives the random number and the signature value from the service providing server, calculates the signature value of the received random number for the private key registered in the registration means, and the calculated signature value is Revocation confirmation processing is executed depending on whether or not the received signature value matches. Thereby, the used key can be specified reliably.

  (4) According to the present invention, in the attribute authentication system according to any one of (1) to (3), the revocation verification authority server (for example, equivalent to the revocation verification authority server 4 in FIG. 1) There is proposed an attribute authentication system further comprising management means for managing the expiration date of the registered secret key, wherein the management means deletes the secret key whose expiration date has passed from the registration means.

  According to the present invention, the revocation verification station server further includes management means for managing the expiration date of the secret key registered in the registration means, and the management means deletes the secret key whose expiration date has passed from the registration means. In other words, there is a possibility that the number of revoked private keys will increase indefinitely, but in attribute authentication, etc., expiration dates are also managed, so expired private keys that have expired are unnecessary. As a result, the amount of the expired secret key to be managed can be set to an appropriate amount.

(5) The present invention is an anonymous method of the attribute information in the attribute authentication system, the first user terminal, to reliable connected via a network server to send the attribute certificate request 2 (for example, corresponding to step S201 in FIG. 2 or step S302 in FIG. 3) and the trusted server receives the attribute certificate issuance request, A second step (for example, corresponding to step S202 in FIG. 2) of generating an attribute certificate by signing with a signature key for the attribute possessed and transmitting the attribute certificate to the requested user terminal; The third step of transmitting a service provision request to the service provision server connected via the network (for example, step S203 in FIG. And the service providing server that has received the service providing request generates a random number and transmits challenge information to the user terminal (for example, equivalent to step S204 in FIG. 2). And the user terminal receiving the challenge information generates a random number, transforms the attribute certificate received from the trusted server by the generated random number, and transforms the modified attribute certificate , A fifth step (for example, corresponding to step S205 in FIG. 2) of returning a signature value calculated for the challenge information transmitted from the service providing server to the service providing server; A sixth step of verifying the transformed attribute certificate and signature value, respectively, from the service providing server; Revocation confirmation request of the attribute certificate received revocation verification station server, a seventh step of executing a revocation confirmation process of the attribute certificate (e.g., corresponding to step S308 in FIG. 3), in the sixth step When the verification result is valid, an eighth step (for example, corresponding to step S206 in FIG. 2) in which the service providing server provides a service based on the attribute to the user terminal that has made a service provision request; A method for anonymizing attribute information in an attribute authentication system characterized by having

  According to the present invention, a user terminal transmits and receives an attribute certificate issuance request to a reliable server connected via a network connected via the network, and the reliable server receives the attribute certificate. When an issuance request is received, an attribute certificate is generated by signing the user's public key with a signature key for the attribute the user has, and transmits the attribute certificate to the requesting user terminal. Next, the user terminal transmits a service provision request to the service provision server connected via the network, and the service provision server that receives the service provision request generates a random number and transmits challenge information to the user terminal. To do. The user terminal that has received the challenge information generates a random number, transforms the attribute certificate received from the reliable server by multiplying the generated random number, and modifies the modified attribute information and the challenge transmitted from the service providing server. The signature value calculated for the information is returned to the service providing server. The service providing server verifies each of the modified attribute certificate and signature value, and the revocation checking authority server receives the revocation checking request from the service providing server, and executes the revocation checking process. Then, when the verification result is valid, the service providing means provides a service based on the attribute to the user terminal that requested the service provision. As a result, anonymity can be guaranteed at the time of attribute authentication and anonymization can be performed without requiring communication with a third party, and revocation confirmation is possible even when anonymous authentication is performed. Become.

(6) The present invention relates to the anonymization method of attribute information in the attribute authentication system of (5), in the seventh step, the revocation verification authority server receives a random number and a signature value from the service providing server, and wherein the signature value of the random number received for private key registered by the user terminal were respectively calculated, to execute the invalidation confirmation processing according to whether the calculated signature value matches the signature value received A method for anonymizing attribute information in an attribute authentication system is proposed.

  According to the present invention, the revocation verification station server receives the random number and the signature value from the service providing server, calculates the signature value of the received random number for the private key registered by the user terminal, and calculates the calculated signature value. The revocation check process is executed depending on whether or not the received signature value matches. Thereby, the used key can be specified reliably.

(7) The present invention is a computer program that causes a computer to perform anonymization of attribute information in an attribute authentication system, and a user terminal is connected to a reliable server connected via a network. the first step to send the attribute certificate request against (e.g., corresponding to step S302 in step S201 or 3 in FIG. 2) and the trusted server, receiving the attribute certificate request A second step of generating an attribute certificate by signing the user's public key with a signature key for the attribute of the user and transmitting it to the user terminal that requested it (for example, the step of FIG. 2). Corresponding to S202), and the user terminal needs to provide service to a service providing server connected via the network. And the service providing server that has received the service providing request generates a random number to send challenge information to the user terminal. And the user terminal that has received the challenge information generates a random number and generates it in the attribute certificate received from the reliable server (for example, corresponding to step S204 in FIG. 2) A fifth step (for example, returning a modified attribute certificate and a signature value calculated for the challenge information transmitted from the service providing server to the service providing server while multiplying by a random number) , Corresponding to step S205 in FIG. 2), and the service providing server sends the modified attribute certificate and signature. A sixth step of verifying respectively the value, the service received revocation verification station server revocation checking request for attribute certificate from providing server, the seventh to perform revocation checking processing of the attribute certificate When the verification result in step (for example, step S308 in FIG. 3) and the verification result in the sixth step is valid, the service providing server provides a service based on the attribute to the user terminal that has made a service providing request. And a computer program for causing a computer to execute anonymization of attribute information in an attribute authentication system characterized by having an eighth step (for example, corresponding to step S206 in FIG. 2).

  According to the present invention, when a user terminal sends and receives an attribute certificate issuance request to a reliable server connected via a network, and the reliable server receives an attribute certificate issuance request In addition, an attribute certificate is generated by signing the user's public key with a signature key for the attribute the user has, and transmits the attribute certificate to the requested user terminal. Next, the user terminal transmits a service provision request to the service provision server connected via the network, and the service provision server that receives the service provision request generates a random number and transmits challenge information to the user terminal. To do. The user terminal that has received the challenge information generates a random number, transforms the attribute certificate received from the reliable server by multiplying the generated random number, and modifies the modified attribute information and the challenge transmitted from the service providing server. The signature value calculated for the information is returned to the service providing server. The service providing server verifies each of the modified attribute certificate and signature value, and the revocation checking authority server receives the revocation checking request from the service providing server, and executes the revocation checking process. Then, when the verification result is valid, the service providing means provides a service based on the attribute to the user terminal that requested the service provision. As a result, anonymity can be guaranteed at the time of attribute authentication and anonymization can be performed without requiring communication with a third party, and revocation confirmation is possible even when anonymous authentication is performed. Become.

(8) The present invention relates to a computer program for causing a computer to execute anonymization of attribute information in the attribute authentication system of (7). In the seventh step, the revocation verification station server receives a random number from the service providing server. receiving the signature value, the signature value of the random number received for private key registered by the user terminal were respectively calculated, the revocation confirmation processing according to whether the calculated signature value matches the signature value received The computer program which makes a computer perform the anonymization of the attribute information in the attribute authentication system characterized by performing is proposed.

  According to the present invention, the revocation verification station server receives the random number and the signature value from the service providing server, calculates the signature value of the received random number for the private key registered by the user terminal, and calculates the calculated signature value. The revocation check process is executed depending on whether or not the received signature value matches. Thereby, the used key can be specified reliably.

  According to the present invention, a reliable server generates key information of a public key and a secret key to which an issuer's signature is attached as attribute information, and a user terminal generates the generated random number as a public key and the issuer's signature. The attribute certificate consisting of is transformed, sent to the service providing server, and the service providing server verifies that the relationship between the attribute certificate and the signing key is established as a formal signature. By providing, it is possible to realize anonymization of attribute information at the time of authentication without requiring communication with a third party, and it is possible to protect privacy when exchanging attribute information.

  In addition, regarding the setting of information such as the validity period, which is a concern because the attribute information is only key information, it can be solved by periodically updating the signature key, and multiple signature keys can be assigned to each attribute. There is an effect that fairness of service enjoyment can be secured by allocating and managing in parallel.

  Further, according to the present invention, the revocation verification station server receives the random number and the signature value from the service providing server, calculates the signature value of the received random number for the secret key registered by the user terminal, and calculates In order to execute revocation confirmation processing depending on whether the signature value matches the received signature value, the private key requested to be revoked by the user is revoked, and the service provider confirms the revocation of the private key during authentication processing. be able to. Therefore, even when anonymous authentication is performed, there is an effect that the revocation confirmation of the secret key can be performed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Note that the constituent elements in the present embodiment can be appropriately replaced with existing constituent elements and the like, and various variations including combinations with other existing constituent elements are possible. Therefore, the description of the present embodiment does not limit the contents of the invention described in the claims.

<System configuration of attribute authentication system>
FIG. 1 is a diagram illustrating an example of a system configuration of an attribute authentication system according to an embodiment of the present invention.
As shown in FIG. 1, the attribute authentication system according to the present embodiment includes a user terminal 1, a service providing server (hereinafter simply referred to as an SP server 2) managed and operated by a service provider, and an attribute certificate authority (CA). It consists of a reliable server managed and operated (hereinafter simply referred to as CA server 3), a revocation verification authority server 4 managed and operated by a revocation verification authority, and a secret key management server 5, all of which are connected via a network 6. Has been.

  The user terminal 1 is equipped with an attribute authentication client module 11. The attribute authentication client module 11 transmits a service provision request to the SP providing server 2, generates a random number, and receives the attribute certificate received from the CA server 3. Is transformed by multiplying the generated random number and functions as a means for returning the modified attribute information and the signature value calculated for the challenge information transmitted from the SP server 2 to the SP server 2.

  The SP server 2 has an attribute authentication server module 21 that verifies the validity of the attribute certificate and signature value modified by the user terminal 1. When it is determined that it is valid, it functions as a means for providing a service based on the attribute to the user terminal 1 that has requested the service provision.

  The CA server 3 has an attribute certificate issuance module 31 installed. When the attribute certificate issuance module 31 receives an attribute certificate issuance request from the user terminal 1, the user receives the user's public key from the user's public key. It functions as means for generating an attribute certificate by signing with a signature key for the attribute it has and sending it to the user terminal 1 that requested it. It also functions as means for assigning a plurality of signature keys to each attribute and periodically updating the signature keys.

  The revocation verification station server 4 registers the secret key to be revoked transmitted from the user terminal 1, and upon receiving a revocation confirmation request from the SP server 2 during the authentication process, executes the revocation confirmation process, and results of the revocation confirmation process To the SP server 2 as a means.

  The secret key management server 5 is a reliable server that registers a secret key when the user generates it, and functions as a backup when the user wants to revoke the secret key. In the present embodiment, the configuration in which the secret key management server 5 is provided separately from the revocation verification authority server 4 is shown. However, the secret key generated in the revocation verification authority server 4 may be registered. Good.

<Operation sequence of attribute authentication system>
FIG. 2 is an operation sequence diagram showing the operation flow of the entire attribute authentication system according to the embodiment of the present invention in time series, and FIG. 3 is a flowchart showing the operation flow of the user terminal. . The operation sequence diagram shown in FIG. 2 also shows the procedure of the attribute information anonymization method in the attribute authentication system of the present invention.
Hereinafter, the operation of the attribute authentication system shown in FIG. 1 will be described in detail with reference to FIGS.

  First, the attribute authentication client module 11 of the user terminal 1 generates a pair of the user's private key x and public key y = xP (step S301 in FIG. 3), and transmits an attribute certificate issuance request to the CA server 3. (Step S201 in FIG. 2). The attribute certificate issuing module 31 of the CA server 3 that has received the attribute certificate issuing request signs the public key y with the signature key for the attribute possessed by the user.

  At this time, the signature key having the longest validity period is used. The signature is zy when the signature private key is z and the corresponding public key is zP. For this reason, the attribute certificate issuing module 31 of the CA server 3 transmits {y, zy} as the attribute certificate to the user terminal 1 (step S202 in FIG. 2).

  FIG. 4 conceptually shows how to manage the effective period. In FIG. 4, t on the horizontal axis indicates the flow of time. According to the present invention, since the attribute information is only key information, it is necessary to manage a new effective period. For this reason, as shown in FIG. 4, the attribute certificate issuance module 31 of the CA server 3 assigns a plurality of signature keys for each attribute, and manages the validity period by periodically updating the combination. ing. At that time, a plurality of title keys assigned for each attribute are managed in parallel so that a user who can enjoy the service only for a very short period does not occur.

  In order to assign a signature key having the longest valid period, for example, as shown in FIG. 4, if an attempt is made to assign a key in the latter half of the usage period of the key A, the attribute of the CA server 3 The certificate issuing module 31 assigns the signature key D or the signature key E to the attribute authentication client module 11 of the user terminal 1.

  Next, the attribute authentication client module 11 of the user terminal 1 receives the attribute certificate composed of the public key and the signature key from the attribute certificate issuing module 31 of the CA server 3 (step S303 “Yes” in FIG. 3). Then, a service provision request is generated (step S304 in FIG. 3), and the generated service provision request is transmitted to the attribute authentication server module 21 of the SP server 2 (step S203 in FIG. 2).

  The attribute authentication server module 21 of the SP server 2 that has received the service provision request generates a random number r and transmits it as challenge information to the attribute authentication client module 11 of the user terminal 1 (step S204 in FIG. 2).

  The attribute authentication client module 11 of the user terminal 1 that has received the challenge information first transforms the attribute certificate. Specifically, a random number f is generated, and the attribute certificate {y, zy} previously received from the CA server 3 is multiplied by the random number to be transformed into {fy, fzy} (step S306 in FIG. 3). At this time, the secret key is also transformed into fx.

  Subsequently, the attribute authentication client module 11 of the user terminal 1 calculates a signature value for the challenge random number r. Here, as the calculation of the signature value, for example, according to the ElGamal signature using the discrete logarithm problem, the following equation (1) is followed.

Next, the attribute authentication client module 11 of the user terminal 1 returns the modified attribute certificate and the previously calculated signature value to the SP server 2 (step S205 in FIG. 2 and step S307 in FIG. 3). The attribute authentication server module 21 of the SP server 2 that has received the attribute certificate and the signature value first verifies the transmitted attribute certificate. Here, paring calculation is used for verification. Specifically, when the paring calculation is expressed by e ( ^* , ^* ), the SP server 2 determines whether e (y, zQ) is satisfied.

  Next, the service provider performs certificate revocation confirmation (step S308 in FIG. 3). Specifically, processing as shown in FIG. 5 is executed. That is, when the user wants to revoke his / her private key, the user terminal 1 transmits the secret key to the revocation verification station server 4 (step S501 in FIG. 5). At this time, it is confirmed by server authentication that the server is a correct revocation verification server.

  In this process, it is assumed that the private key is backed up in advance by the user. However, when the private key is generated, the private key is registered in the private key management server 5 and the private key is to be revoked. In this case, it may be transferred to the revocation verification authority server. The secret key management server 5 and the revocation verification station server 4 may be different or the same entity.

  When requesting revocation confirmation, the service provider transmits the random number transmitted by the service provider to the user terminal 1 and the signature value transmitted from the user terminal 1 to the revocation verification station server 4 (FIG. 5). Step S502).

  The revocation verification authority server identifies the used private key by calculating the signature value of the random number in order for the revoked private key (step S503 in FIG. 5). If the secret key has not expired, the secret key having the same signature value is not registered in the revocation verification authority server.

  If the revocation verification authority server 4 determines that the private key with the same signature value has been registered as revoked, it notifies the SP server 2 that the private key has expired (step in FIG. 5). S503). On the other hand, when the revocation verification authority server 4 determines that the private key having the same signature value has not been registered as revoked, it notifies the SP server 2 that the private key has not been revoked (see FIG. 5 step S503). The expired secret key is deleted from the data area of the expired verification authority server 4 when the expiration date of the secret key has passed.

  Subsequently, the attribute authentication server module 21 of the SP server 2 verifies the returned signature key. For example, the following equation (2) is calculated for the Elgamal signature.

  When the validity of the signature is confirmed and the revocation is confirmed, the SP server 2 determines that the authentication is successful, and provides the user terminal 1 with a service based on the attribute information (step S206 in FIG. 2). Here, successful authentication means that the relationship between the attribute certificate and the signature key is established as a formal signature. After verification of the attribute certificate and signature key and revocation confirmation are established (step S309 “OK” in FIG. 3), the user terminal 1 communicates with the SP server 2 and the user provided by the SP server 2 Can be enjoyed according to the attribute information (step S310 in FIG. 3).

  The specific use of the attribute authentication system and the anonymization method in the system is as follows. In the disclosure of medical information, confirmation of medical qualification or publicly issued by public transportation. It can be used for confirming qualifications such as Silver Pass.

  As described above, the present invention issues, as attribute information, the public key and private key information to which the issuer's signature is attached, and the key information includes a random number generated by the user as the public key and the issuer. Any modification is possible by multiplying the attribute certificate consisting of the signature. Thus, anonymization of attribute information at the time of authentication can be realized without requiring communication with a third party, and privacy protection when exchanging attribute information becomes possible.

  In addition, it becomes possible by periodically updating the signature key regarding the setting of information such as the validity period, which is concerned because the attribute information becomes only the key information, and assigning a plurality of signature keys to each attribute, By managing in parallel, the fairness of service enjoyment can be secured. Furthermore, the secret key requested to be revoked by the user can be revoked, and the revocation confirmation can be performed during the authentication process.

  Note that the attribute authentication client module 11, the attribute authentication server module 21, and the attribute certificate issuance module 31 shown in FIG. 1 are programs executed by the user terminal 1, the SP server 2, and the CA server 3, respectively. Is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into each of the user terminal 1, the SP server 2, and the CA server 3 (all computer systems) and executed. An attribute authentication system can be realized. The computer system here includes an OS and hardware such as peripheral devices.

  Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW (World Wide Web) system is used. The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.

  The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

  The embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the embodiments, and includes designs and the like that do not depart from the gist of the present invention.

It is a figure which shows an example of the system configuration | structure of the attribute authentication system which concerns on embodiment of this invention. It is a figure which shows the operation sequence of the whole attribute authentication system which concerns on embodiment of this invention. It is a flowchart which shows operation | movement of the user terminal in the attribute authentication system which concerns on embodiment of this invention. It is the operation | movement conceptual diagram quoted in order to demonstrate the management method of the effective period of the attribute information of the attribute authentication system which concerns on embodiment of this invention. It is a process flowchart regarding the revocation verification in the attribute authentication system which concerns on embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... User terminal, 2 ... Service provision server (SP server), 3 ... Attribute certification authority server (CA server), 4 ... Revocation verification authority server, 5 ... Secret key management server, 6 ... Network, 11 ... Attribute authentication client module, 21 ... Attribute authentication server module, 31 ... Attribute certificate issuing module

Claims (8)

An attribute authentication system in which a reliable server, a user terminal, a service providing server, and an expiration verification station server are connected via a network,
The trusted server, when receiving an attribute certificate issuance request from the user terminal, generates an attribute certificate by signing the user's public key with a signature key for the attribute the user has And transmitting means for transmitting the generated attribute certificate to the user terminal that requested it,
The user terminal is transformed by generating service provision request transmitting means for transmitting a service provision request to the service providing server, generating a random number, and multiplying the generated random number by the attribute certificate received from the reliable server. Replying means for returning the modified attribute certificate and the signature value calculated for the challenge information transmitted from the service providing server to the service providing server,
The service providing server verifies the validity of the modified attribute certificate and signature value, respectively, and determines that it is valid for the user terminal that requested the service provision. Service providing means for providing a service based on the attribute,
The revocation verification station server includes a registration means for registering the secret key transmitted from the user terminal, during the authentication process, upon receiving the invalidation confirmation request for attribute certificate from the service providing server, the revocation of the attribute certificate Revocation confirmation processing result reply means for executing confirmation processing and returning the revocation confirmation processing result of the attribute certificate to the service providing server;
An attribute authentication system characterized by comprising:   The attribute authentication system according to claim 1, wherein the reliable server further includes an updating unit that assigns a plurality of the signature keys to each attribute and periodically updates the signature key. The revocation verification station server receives a random number and a signature value transmitted as the challenge information from the service providing server, calculates a signature value of the received random number for the secret key registered in the registration unit, 3. The attribute authentication system according to claim 1, wherein the revocation check process is executed depending on whether or not the calculated signature value matches the received signature value. The revocation verification station server further comprises management means for managing the expiration date of the secret key registered in the registration means,
4. The attribute authentication system according to claim 1, wherein the management unit deletes the secret key whose expiration date has passed from the registration unit. A method for anonymizing attribute information in an attribute authentication system,
User terminal, a first step of relative reliable connected via a network server to send the attribute certificate request,
When the trusted server receives the attribute certificate issuance request, it generates an attribute certificate by signing the user's public key with a signature key for the attribute the user has, and A second step of transmitting to the user terminal;
A third step in which the user terminal transmits a service provision request to a service provision server connected via the network;
The service providing server that has received the service providing request generates a random number and transmits challenge information to the user terminal;
The user terminal that has received the challenge information generates a random number, modifies the attribute certificate received from the reliable server, and modifies the generated attribute certificate, and the modified attribute certificate and the service provision A fifth step of returning a signature value calculated for the challenge information transmitted from the server to the service providing server;
A sixth step in which the service providing server verifies each of the transformed attribute certificate and signature value;
A revocation verification authority server that receives a revocation confirmation request for an attribute certificate from the service providing server, and executes a revocation confirmation process for the attribute certificate ;
An eighth step in which when the verification result in the sixth step is valid, the service providing server provides a service based on the attribute to the user terminal that has made a service provision request;
A method for anonymizing attribute information in an attribute authentication system, comprising: In the seventh step, the revocation verification station server receives a random number and a signature value from the service providing server, calculates a signature value of the received random number for the secret key registered by the user terminal, 6. The method for anonymizing attribute information in an attribute authentication system according to claim 5, wherein the revocation checking process is executed depending on whether or not the calculated signature value matches the received signature value. A computer program for causing a computer to perform anonymization of attribute information in an attribute authentication system,
User terminal, a first step of relative reliable connected via a network connected via the network server to send the attribute certificate request,
When the trusted server receives the attribute certificate issuance request, it generates an attribute certificate by signing the user's public key with a signature key for the attribute the user has, and A second step of transmitting to the user terminal;
A third step in which the user terminal transmits a service provision request to a service provision server connected via the network;
The service providing server that has received the service providing request generates a random number and transmits challenge information to the user terminal;
The user terminal that has received the challenge information generates a random number, modifies the attribute certificate received from the reliable server, and modifies the generated attribute certificate, and the modified attribute certificate and the service provision A fifth step of returning a signature value calculated for the challenge information transmitted from the server to the service providing server;
A sixth step in which the service providing server verifies each of the transformed attribute certificate and signature value;
A revocation verification authority server that receives a revocation confirmation request for an attribute certificate from the service providing server, and executes a revocation confirmation process for the attribute certificate ;
An eighth step in which when the verification result in the sixth step is valid, the service providing server provides a service based on the attribute to the user terminal that has made a service provision request;
A computer program for causing a computer to perform anonymization of attribute information in an attribute authentication system characterized by comprising: In the seventh step, the revocation verification station server receives a random number and a signature value from the service providing server, calculates a signature value of the received random number for the secret key registered by the user terminal, 8. The computer program for causing a computer to perform anonymization of attribute information in the attribute authentication system according to claim 7, wherein the revocation checking process is executed depending on whether or not the calculated signature value matches the received signature value. .

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