JP2007019712A - Mobile terminal device and attribute information exchange system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To protect user's privacy by dividing attribute information so that only necessary attribute information is presented and reissuing a certificate of the divided attribute information. <P>SOLUTION: An attribute information exchange system stores the attribute information in a mobile terminal device 3a and provide services corresponding to the attribute information by exchanging the attribute information. The mobile terminal device 3a has a tamperproof area 33, and divides the property information to present only necessary property information to an opposite-side user and reissues a certificate of the divided attribute information in the tamperproof area to protect the user's privacy. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mobile terminal device and an attribute information exchange system suitable for use in storing attribute information and providing services according to the attribute by actively exchanging the attribute information.

2. Description of the Related Art Conventionally, as an electronic authentication technique on a network, a method for verifying whether attribute information received from a communication partner is valid is known. As an example, in the method using a public key certificate, the validity of each attribute information is proved by a third party organization, and the attribute certificate is issued.
When verifying whether or not the attribute information received from the communication partner is valid, the user needs to obtain an attribute certificate corresponding to the attribute information received from the third party organization (for example, patent Reference 1).
JP 2001-209313 A

By the way, when a user receives a service from a service provider or exchanges information with another user, it is required to exchange an attribute certificate corresponding to the attribute information.
However, since the attribute certificate described above is issued collectively for a plurality of attribute information such as a user's occupation, affiliation, qualification, current position information, etc., the user (client) who presents the attribute information must Unnecessary attribute information is also disclosed to users (clients) or service providers (servers) who acquire information, and therefore a problem related to privacy protection has been left as a technical problem.

  The present invention has been made based on the above circumstances, dividing attribute information so that only necessary attribute information can be presented to the other party, and reissuing the certificate of the divided attribute information, thereby protecting the privacy of the user. An object of the present invention is to provide a mobile terminal device and an attribute information exchange system that are realized.

  In order to solve the above-described problems, the present invention is a portable terminal device having a tamper-resistant area, which captures an attribute certificate including a plurality of attribute information and partial attribute information to be presented, and stores it in the tamper-resistant area The requested attribute input unit, the partial attribute information desired to be presented are verified, and reissue information including the attribute name obtained as a result of the verification and guarantee information for guaranteeing the validity of the partial attribute information is generated and output. And a reissue information output unit.

  In the present invention, the reissue information output unit collates the attribute certificate and the revocation information of the attribute certificate imported from the outside with the owner information or the public key certificate held in the mobile terminal device. The attribute information is verified and the owner information is verified, the attribute name acquisition unit for acquiring the attribute name, the attribute name and the partial attribute information to be presented are collated, and the partial attribute information is And an identification information generation unit that generates identification information including the partial attribute information, and a device-specific key or user key information is input to the identification information. And a guarantee information generating unit for generating guarantee information for guaranteeing the identification information.

  The present invention is also an attribute information exchange system that stores attribute information in a mobile terminal device and provides services according to the attribute information by exchanging the attribute information, and the mobile terminal presenting the attribute information The apparatus signs a challenge information receiving unit that receives challenge information from a mobile terminal device that is a communication partner or a computer managed and operated by a provider, and guarantee information of partial attribute information to be presented for the challenge information, and the part A signature information transmission unit that transmits the signature information including attribute information, and the terminal device that acquires the attribute information or a computer managed and operated by a service provider receives and verifies the transmitted guarantee information. And a signature information verification unit that performs communication based on the verification result.

  Further, the present invention is an attribute information exchange system comprising a server and a plurality of portable terminal devices that are connected via a network and communicate according to the attribute information by exchanging the attribute information. The terminal device transmits an attribute presentation request based on an attribute certificate including a plurality of attribute information and partial attribute information desired to be presented from the attribute information, and the server receives the attribute presentation request. The partial attribute information desired to be presented is verified, and reissue information including the attribute name obtained as a result of the verification and guarantee information for guaranteeing the validity of the partial attribute information is generated, and the requested mobile terminal device Transmitting.

According to the present invention, in an attribute information exchange system that stores attribute information in a mobile terminal device and provides services according to the attribute information by exchanging the attribute information, the mobile terminal device is provided with a tamper-resistant region, By dividing the attribute information so that only the attribute information can be presented to the other party, and reissuing the certificate of the attribute information divided within the tamper-resistant area, it is possible to realize privacy protection for the user. The same effect can also be obtained when the server reissues the certificate of the divided attribute information.
In addition, according to the present invention, by creating a certificate of partial attribute information using a tamper resistant area, it becomes possible to divide the attribute certificate in the user's local environment, and communication with the outside becomes unnecessary. It is possible to reduce communication costs and prevent information from leaking to an external network. Furthermore, since attribute information can be easily exchanged between mobile terminals, services using attribute information can be provided, and the purpose of use of mobile terminal devices, especially mobile phone terminals, has been dramatically expanded. To do.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an example of a system configuration of an attribute information exchange system according to an embodiment of the present invention.
In FIG. 1, an issue center 1 is an organization that issues encryption keys used for attribute information such as a user's occupation, affiliation, qualification, and current location information, and is an organization that operates in a local community, for example. The service provider (SP2) is an organization that relays data communication between the user's mobile terminal devices 3a and 3b or between the user's mobile terminal devices 3a and 3b and the issuing center 1. Here, a mobile phone having an Internet connection environment is illustrated as the mobile terminal devices 3a and 3b. Each of the computer managed and operated by the issuing center 1, the computer managed and operated by the SP 2, and the mobile terminal devices 3 a and 3 b possessed by the users A and B are each a communication network such as an IP (Internet Protocol) network 4. Connected through.

FIG. 2 is a schematic diagram showing an encryption method in the ID type encryption method used in the embodiment of the present invention.
The ID-type encryption method is a method for generating a public key (decryption key) for decryption (verification) from ID information and further generating a secret key (encryption key) for encryption (signature) from the public key. The feature of the ID-type cryptosystem is that there are many types of public keys because public keys are generated from meaningful ID information, and the public keys themselves can have meaningful information.

Here, the ID information means information including the attribute information described above. When there is a restriction so that the attribute information to be exchanged cannot be transferred to the exchange partner, the ID information includes information for identifying the individual (Uid) and information such as the telephone numbers of the mobile terminal devices 3a and 3b. It is possible to clearly prove the owner.
When exchanging qualifications and the like that are valid only within a certain period as attribute information, the validity of the attribute information received from the other party can be determined by including the issue time in the ID information.
Furthermore, when it is not necessary to limit the attribute information specially, such as when hobbies / preferences are exchanged as attribute information, only the attribute information is used as ID information. In this way, by selectively using what information is selected in addition to the attribute information as the information included in the ID information, it can be applied to various services performed using the attribute information.

In FIG. 2, in the ID type encryption method, first, ID information is converted into a public key using a one-way function A. This one-way function A is possessed by the issuing center 1 and the mobile terminal devices 3a and 3b. Subsequently, a secret key is generated from the public key and the center secret key using the one-way function B. The center secret key and the one-way function B are possessed only by the issuing center 1, and the secret key can be generated only by the issuing center 1.
That is, the portable terminal devices 3a and 3b that do not have the center secret key cannot generate the secret key from the public key. On the other hand, a center public key is generated from the center secret key using the one-way function C. The one-way function C is possessed only by the issuing center 1, and the center public key can be generated only by the issuing center 1. The generated center public key is distributed in advance to the mobile terminal devices 3a and 3b.

FIG. 3 is a block diagram showing functional expansion of the internal configuration of the portable terminal device according to the embodiment of the present invention.
The mobile terminal device 3 according to the embodiment of the present invention includes a tamper resistant device 30 such as a UIM (User Identity Module). The tamper resistant device 30 refers to a device or element that is resistant to unauthorized acquisition or falsification of information, and the UIM refers to, for example, an IC card in which contractor information issued by a mobile phone company is recorded. .

The configuration of the tamper resistant device 30 is functionally largely divided into a request attribute input unit 31, an attribute name acquisition unit 32, a storage unit (tamper resistant region 33), an ID generation unit 34, and a guarantee information generation unit 35. Separated.
The following functions of the request attribute input unit 31, the attribute name acquisition unit 32, the ID generation unit 34, and the guarantee information generation unit 35 described above are incorporated in the mobile terminal device 3a (CPU). This is realized by sequentially reading out and executing a UIM program operating in the tamper resistant area 33 recorded in a memory (none of which is shown).

Specifically, the request attribute input unit 31 takes in an attribute certificate (AC40) including a plurality of attribute information and partial attribute information to be presented from the mobile terminal device 3a, and obtains an attribute name acquisition unit 32, an ID generation unit 34, and the like. With the function to supply to.
Further, the attribute name acquisition unit 32 includes the AC 40 and the AC 40 revocation information captured from the outside, the owner information (Uid), or the public key certificate (PKC) possessed inside the portable terminal device 3a (tamper resistant area 33). And verifying the validity of the attribute information and the owner information, acquiring the attribute name based on the verification result, and supplying the attribute name to the ID generation unit 34. The ID generation unit 34 compares the attribute name with the partial attribute information to be presented, detects that the partial attribute information is included in the attribute certificate whose validity has been confirmed, and includes identification information (ID ) And supply it to the outside and to the guarantee information generation unit 35. The guarantee information generation unit 35 has a function of generating guarantee information such as a secret key for guaranteeing the identification information by inputting device-specific key information for the identification information generated by the ID generation unit 34.

The attribute name acquisition unit 32, the ID generation unit 34, the guarantee information generation unit 35, and the tamper-resistant area 33 constitute a reissue information output unit shown in the claims. It has a function of verifying partial attribute information to be presented and generating and outputting reissue information including an attribute name obtained as a result of the verification and information for guaranteeing the validity of the partial attribute information. FIG. 4 shows an outline of the operation of the reissue information output unit.
That is, the mobile terminal device 3a (UIM program) divides the attributes so that only necessary attribute information can be presented to the other party (partial attribute information), takes in the attribute certificate (AC), and verifies / The reissue process is executed, and the requested partial attribute information and the guarantee information of the partial attribute information are presented to the communication partner.

FIG. 5 is a flowchart cited for explaining the processing procedure of the verification / reissue processing of the mobile terminal device according to the embodiment of the present invention.
Hereinafter, the operation of the mobile terminal device according to the embodiment of the present invention shown in FIG. 3 will be described in detail with reference to the flowchart shown in FIG.

First, the user issues a public key certificate from the certificate authority and an attribute certificate in which a plurality of attribute information is described from the attribute authority. Here, the attribute certificate is managed in association with the public key certificate. The public key certificate (PKC) may be stored in advance in the tamper resistant area 33 of the mobile terminal device 3a.
Subsequently, the user stores the issued attribute certificate (AC) in the mobile terminal device 3a. A user acquires a plurality of attribute information by the same method, and stores them in his / her mobile terminal device 3a. Further, when the user presents one of the attributes to the other mobile terminal device 3b or the server 2 of the service provider, the user operates the mobile terminal device 3a to display the attribute certificate and the attribute information desired to be presented in the tamper resistant area. 33. Specifically, first, the request attribute input unit 31 configuring the mobile terminal device 3a takes in the request attribute information input by the user and supplies it to the attribute name acquisition unit 32 and the ID generation unit 34 (step S501).

Then, the attribute name acquisition unit 32 checks whether the AC 40 is associated with the public key certificate of the user managed by the AC 40 (step S502), and subsequently, the signature of the attribute certificate is obtained. Verification is performed (step S503), and revocation confirmation of the attribute certificate is also performed based on the revocation information acquired from the outside (step S504).
The attribute name acquisition unit 32 further confirms that the attribute requested by the user is included in the attribute certificate whose validity has been confirmed (step S505), and the attribute name includes the owner, the issue time, and the like. Is used as attribute information. In the case of the ID type encryption described above, this information is used as identification information (ID) (step S506).

  On the other hand, the guarantee information generation unit 35 generates information for guaranteeing the validity of the attribute information. Specifically, it is possible to sign with a device-specific key (master key), or with a user's private key (step S507). In the case of ID type encryption, key information linked from ID to ID is generated as guarantee information using a secret key unique to the apparatus. Then, the attribute information and a secret key that guarantees its validity are output and returned to the user (step S508).

FIG. 6 is an operation sequence diagram quoted for explaining the operation of the attribute exchange system according to the embodiment of the present invention. Here, between the mobile terminal device 3a of user A and the mobile terminal device 3b of user B, FIG. The procedure for exchanging ID information is shown in FIG.
When the user A acquires the attribute information of the user B, first, challenge information such as a random number is transmitted from the mobile terminal device 3a (user A) to the mobile terminal device 3b (user B) (step S601). When the mobile terminal device 3b receives the challenge information (challenge information receiving unit), the ID information to be disclosed is selected from the ID information stored in the device, and the challenge information is signed with a secret key corresponding to the ID information ( Step S602). Thereafter, the ID information and the signature information are transmitted to the mobile terminal device 3a (signature information transmission unit, step S603).

When the portable terminal device 3a receives the ID information and the signature information, first, a public key is generated from the ID information using the one-way function A (step S604). Subsequently, the signature information is verified with the generated public key, and the validity of the ID information is confirmed (signature information verification unit, step S605). If the verification of the ID information is successful, the mobile terminal device 3a stores the attribute information included in the ID information as the user B attribute information. When the user B acquires the attribute information of the user A, the challenge information is transmitted from the mobile terminal device 3b to the mobile terminal device 3a, and the same procedure is executed.
Note that, according to the above-described embodiment of the present invention, only the procedure for exchanging ID information between the mobile terminal device 3a of the user A and the mobile terminal device 3b of the user B has been described. When exchanging ID information with the service provider server 2 (presentation of attributes), the operation of the mobile terminal device 3a (3b) of the user A (B) who obtains the attribute information is replaced with the service provider server 2. To follow a similar procedure.

  According to the method shown in FIG. 6, it is possible to generate and verify a public key from received ID information, and there is no need to connect to the issuing center 1 when exchanging attribute information. In the attribute information exchange procedure, data transmission / reception is limited between the mobile terminal devices 3a and 3b, and ID information is not leaked to other networks. Furthermore, it is possible to verify even when unknown attribute information that is not stored in the mobile terminal device 3a (3b) is received. For this reason, it is possible to easily verify attribute information that clearly differs for each individual, such as an address.

According to the above-described embodiment of the present invention, the example in which the attribute information and the key information thereof are generated in the tamper resistant device of the mobile phone terminal device 3a has been described, but the mobile phone terminal device 3a, for example, the issuing center 1 It is also possible for an external trusted server to generate such information.
FIG. 7 shows a system outline of an attribute information exchange system according to another embodiment of the present invention. Hereinafter, an attribute information exchange system according to another embodiment of the present invention will be described in detail with reference to FIG.

First, user A (mobile terminal device 3a) has a public key certificate issued from a certificate authority and an attribute certificate in which a plurality of attributes are described from an attribute authority (steps S71 and S72). The attribute certificate is managed in association with the public key certificate. The public key certificate may be stored in advance in the tamper-resistant area of the user's mobile phone terminal device 3a.
Subsequently, the user A (mobile terminal device 3a) stores the issued public key certificate in the mobile terminal device 3a. User A (mobile terminal device 3a) acquires a plurality of attribute information by the same method, and stores it in its own mobile terminal device 3a.

  For example, when the user A (mobile terminal device 3a) presents certain attribute information to the user B (mobile terminal device 3b), first, the user A (mobile terminal device 3b) accesses the issuing center 1 (trusted server), Request the generation of reissue information including guarantee information that guarantees the validity of the partial attribute information by sending the public key certificate, attribute certificate, and request attribute (attribute to be presented) received from the attribute authority. (Issue attribute presentation request) (step S73). At that time, the user A (mobile terminal device 3a) authenticates the attribute certificate authority. Further, a secure session (encrypted communication path) is established by SSL (Secure Socket Layer) or the like.

Next, the issuing center 1 (trusted server) first checks whether the attribute certificate is associated with the user's public key certificate, and then performs user authentication using the public key certificate. . User authentication is as follows: (1) Issuing center 1 (trusted server) confirms public key certificate (including revocation status), (2) Sends random number as challenge to user, (3) User is secret to random number The signature is signed with the key, and the signature is returned. (4) The issuing center 1 (trusted server) verifies the signature, and the steps (1) to (4) are executed. Further, the issuing center 1 (trusted server) verifies the signature of the attribute certificate and performs revocation confirmation.
Then, the issuing center 1 (trusted server) confirms that the attribute requested by the user A (mobile terminal device 3a) is included in the certificate whose validity has been confirmed, and issues the issue time in the attribute name. Etc. to give attribute information. In the case of ID type encryption, this information is used as an ID.

  Further, the issuing center 1 (trusted server) generates information for guaranteeing the validity of the attribute information. For example, signing with a key unique to AA can be considered. In the case of ID type encryption, key information associated with an ID is generated from the ID using a secret key unique to AA. Then, the issuing center 1 (trusted server) returns the attribute information and key information (guarantee information) for guaranteeing its validity to the user A (mobile terminal device 3a) who requested it (step S74). . In that case, a secure session established by SSL or the like is used.

The procedure when user A (mobile terminal device 3a) and user B (mobile terminal device 3b) exchange attribute information is as follows in the case of ID-type encryption.
That is, when the user A (mobile terminal device 3a) acquires the attribute information of the user B (mobile terminal device 3b), first, a random number is given from the user A (mobile terminal device 3a) to the user B (mobile terminal device 3b). Send challenge information such as At this time, the user B (mobile terminal device 3b) signs the challenge information with a secret key (guarantee information) having an attribute desired to be presented, and returns only the signature information. At this time, ID information (partial attribute information) is also transmitted.

Subsequently, the user A (mobile terminal device 3a) verifies the returned signature information. At that time, a public key is created and verified using the ID information. Also, the issue time included in the ID is confirmed. As a result, if the verification process is successful, it is recognized as the owner of the valid attribute.
When user B (mobile terminal device 3b) acquires attribute information of user A (mobile terminal device 3a), challenge information is transmitted from user B (mobile terminal device 3b) to user A (mobile terminal device 3a). Thereafter, the same procedure is executed.

  Note that, according to the above-described embodiment of the present invention, only the procedure for exchanging ID information between the mobile terminal device 3a of the user A and the mobile terminal device 3b of the user B has been described. When exchanging ID information with the service provider server 2 (presentation of attributes), the operation of the mobile terminal device 3a (3b) of the user A (B) who obtains the attribute information is replaced with the service provider server 2. The same procedure is followed.

  As described above, the present invention stores the attribute information in the portable terminal device 3a (3b), and exchanges the attribute information to provide the service according to the attribute information, so that the portable terminal device 3a ( 3b) is provided with a tamper-resistant area 33, attribute information is divided so that only necessary attribute information can be presented to the other party, and a certificate of attribute information divided within the tamper-resistant area is reissued. It provides protection. In addition, the user (mobile terminal device 3a) requests a reliable server (issuance center 1) to generate reissue information including guarantee information that guarantees the validity of the partial attribute information. The privacy protection of the user can also be realized by the center 1) reissuing the certificate of the divided attribute information. Furthermore, according to the present invention, by creating a certificate of partial attribute information using the tamper resistant area 33, it becomes possible to divide the attribute certificate in the user's local environment, and communication with the outside becomes unnecessary. It is possible to reduce communication costs and prevent information from leaking to an external network.

  Note that the attribute certificate reissued in the tamper-resistant area is used on an ad hoc basis, so that the expiration date can be set significantly shorter. Therefore, problems such as revocation processing do not occur. Further, by providing a means for confirming revocation of the attribute certificate input to the tamper resistant device such as UIM, partial attribute information cannot be generated from the revoked attribute certificate.

It is the figure which showed an example of the system configuration | structure of the attribute information exchange system which concerns on embodiment of this invention. It is the schematic diagram which showed the encryption method in the ID type encryption system used in embodiment of this invention. It is the block diagram which expanded and showed the internal structure of the portable terminal device which concerns on embodiment of this invention. It is the figure quoted in order to demonstrate the operation | movement outline | summary of the reissue information output part of the portable terminal device which concerns on embodiment of this invention. It is the flowchart quoted in order to demonstrate the process sequence of the verification / reissue process of the portable terminal device which concerns on embodiment of this invention. It is the operation | movement sequence diagram quoted in order to demonstrate operation | movement of the attribute exchange system which concerns on embodiment of this invention. It is the figure which showed the system outline | summary of the attribute information exchange system which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Issuing center, 2 ... Service provider, 3a, 3b ... Portable terminal device, 4 ... IP network, 30 ... Tamper resistant device, 31 ... Request attribute input part, 32 ... Attribute name acquisition part, 33 ... Tamper resistant area, 34 ... ID generation unit, 35 ... Guarantee information generation unit

Claims (4)

A mobile terminal device having a tamper-resistant region,
A request attribute input unit that takes in an attribute certificate including a plurality of attribute information and partial attribute information to be presented from the attribute information, and stores it in the tamper-resistant region
Re-issue information output unit for verifying the partial attribute information to be presented and generating and outputting re-issue information including the attribute name obtained as a result of the verification and guarantee information for guaranteeing the validity of the partial attribute information;
A portable terminal device comprising: The reissue information output unit
Validity of the attribute information and verification of the owner information by comparing the attribute certificate and the revocation information of the attribute certificate imported from the outside with the owner information or the public key certificate held in the mobile terminal device An attribute name acquisition unit for acquiring the attribute name,
The identification that compares the attribute name with the partial attribute information that the user wants to present, confirms that the partial attribute information is included in the attribute certificate whose validity is confirmed, and generates identification information including the partial attribute information An information generator,
A guarantee information generating unit for generating guarantee information for guaranteeing the identification information by inputting a device-specific key or user key information for the identification information;
The mobile terminal device according to claim 1, further comprising: An attribute information exchange system that provides attribute information by storing attribute information in a mobile terminal device and exchanging the attribute information,
The mobile terminal device presenting the attribute information includes a challenge information receiving unit that receives challenge information from a mobile terminal device that is a communication partner or a computer managed and operated by a provider, and partial attribute information that is desired to be presented to the challenge information A signature information transmission unit for signing with the guarantee information and transmitting the signature information including the partial attribute information,
The terminal device that acquires the attribute information or a computer managed and operated by a service provider includes a signature information verification unit that receives and verifies the transmitted guarantee information and performs communication based on the verification result. An attribute information exchange system characterized by that. An attribute information exchange system comprising a server and a plurality of portable terminal devices that are connected via a network and communicate according to the attribute information by exchanging the attribute information;
The portable terminal device
Sending an attribute presentation request based on an attribute certificate including a plurality of attribute information and partial attribute information to be presented from the attribute information;
The server
Receiving the attribute presentation request and verifying the partial attribute information to be presented, generating reissue information including attribute names obtained as a result of the verification and guarantee information for guaranteeing the validity of the partial attribute information Sending to the mobile terminal device
Attribute information exchange system characterized by

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