JP2006268228A - Authentication system using biological information - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an authentication system for preventing the wire-tapping of biological authentication information by preventing "personification" at a collation device side, and for preventing the biological information from being stolen when an unauthorized reading device is used. <P>SOLUTION: A reading device 1 for acquiring biological information is separated from a device 2 which requests authentication so that biological information can be prevented from being stolen by an unreliable biological information reading device, and configured to be provided to each user who should be authenticated. Digital signatures are added to information from a collation device 3 to the reading device 1 by the secret key of the collation device 3 as countermeasures to such a device which behaves like the collecting device 3, and requests authentication processing to the reading device 1 to steal the biological information. Thus, it is possible for the reading device 1 to specify that the received information has not be altered, and that the origin of transmission is the collation device 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a personal authentication system using biometric information.

Conventionally, as a reading apparatus capable of eliminating “spoofing”, for example, a reading apparatus described in Patent Document 1 is known. This includes a reading device that reads biometric information of a user and a verification device that checks whether the read biometric information belongs to a legitimate user. When the reading device reads the biometric information, the reading device generates identification information from the biometric information and sends it to the verification device. Since the collation device stores the identification information generated from the user's biometric information in advance, the identification information sent from the reading device is collated with the stored identification information, thereby confirming whether the user is a legitimate user. . In particular, in the technique described in Patent Document 1 below, for example, a collation device generates an encryption key and transmits it to the reading device, and the reading device encrypts identification information for authentication using the encryption key generated by the collation device. And transmitting it to the verification device. This prevents “spoofing” when data transmitted by the reading device is wiretapped.
JP 2003-283492 A

  However, although the technique described in Patent Document 1 can prevent “spoofing” on the reading device side, it cannot prevent “spoofing” on the collation device side. That is, when a device that behaves like a collation device by pretending to be a collation device is placed between the reading device and the collation device, it is possible to easily steal biological information from information transmitted by the reading device.

  In addition, it is necessary for a user who is authenticated to determine whether the reading device itself is illegal. This is because exposing one's own biometric information to an unauthorized reading device leads to theft of the biometric information.

  An object of the present invention is to prevent eavesdropping of biometric authentication information by preventing “spoofing” on the collation device side, and to prevent the biometric information from being stolen by using an unauthorized reader. It is to provide an authentication system that can be used.

  In order to achieve the above object, the present invention is an authentication system using biometric information, comprising a reading device possessed by a user who is authenticated, a device that requests authentication, and a verification device that performs authentication, The reading device has means for acquiring biometric information, a user ID that is an identifier for identifying a user, a public key PK3 of the verification device, and an information recording unit that stores a secret key SK1 of the reading device, a communication processing unit, And a processing unit that controls the overall operation of the reading device, wherein the device that requests authentication includes a device ID that identifies a device that requests authentication, a secret key SK2 of the device that requests authentication, and disclosure of the verification device An information recording means for storing the key PK3, a communication processing means, and a processing means for controlling the overall operation of the device that requests authentication, wherein the collation device comprises a user ID, biometric information, and Public key PK1 The information recording means storing the device ID and public key PK2 for each device that requires authentication and the secret key SK3 of the verification device, and whether or not the given biometric information has been registered in the information recording means A biometric information collation processing means for collating the information, a communication processing means, and a processing means for controlling the overall operation of the collation apparatus. When the apparatus requesting authentication requests the reader to perform authentication Transmits the signature data obtained by digitally signing the user ID with the secret key SK1 and the user ID from the reading device to the verification device, and the verification device receives the public key PK1 corresponding to the received user ID. Identify from the information recording means, confirm that the user ID has not been altered from the received signature data, generate a random common key CK, record the user ID and the common key CK as a set, and record the common key CK Digitally sign with private key SK3 The signature data and the data obtained by encrypting the common key CK with the public key PK1 are transmitted to the reading device, and the reading device decrypts the received encrypted common key CK with the secret key SK1 and receives the received signature After confirming that the common key CK has not been altered from the data, the biometric information of the user is read by means for obtaining the biometric information, the biometric information is digitally signed with the secret key SK1, and the biometric information is stored in the common key CK. And the user ID, signature data, and encrypted biometric information are transmitted to the device requesting the authentication, and the device requesting the authentication digitally signs the received information with the secret key SK2, and receives the received information. Information, signature data, and device ID are transmitted to the verification device, and the verification device identifies the public key PK2 corresponding to the received device ID from the information recording means, and the information is modified from the received signature data. Not that And obtains a common key CK corresponding to the user ID included in the received information, decrypts the encrypted biometric information included in the received information with the common key CK, and public key PK1 corresponding to the user ID Identifying the biometric information using the public key PK1, confirming that the biometric information is verified with the biometric information registered in the information recording means, and verifying the secret key The digital signature is attached to SK3 and transmitted to the device requesting the authentication, and the device requesting the authentication uses the public key PK3 to confirm that the received verification result is not modified, and the verification result is It is characterized by acquiring.

  ADVANTAGE OF THE INVENTION According to this invention, there is no possibility that biometric information will be stolen, and it can authenticate itself also with respect to the apparatus which requests | requires the untrustworthy authentication which a user utilizes for the first time. In addition, since the digital key signature is added to the information sent from the verification device to the reading device by the public key encryption technology of PKI, the reading device can confirm that the received information has not been altered, and the transmission source is authorized. It can be identified as a verification device. Therefore, spoofing on the collation device side can be prevented. Also, the reading device normally attached to the device that requires authentication is separated from the device that requests authentication, and each user possesses the reading device, thereby preventing theft of biometric information by an unauthorized reading device. I can do it.

  Hereinafter, an embodiment for carrying out the present invention will be specifically described with reference to the drawings.

  FIG. 1 shows a configuration example of an authentication system according to an embodiment of the present invention. As shown in FIG. 1, the authentication system includes a reading device 1 that acquires biometric information, a verification device 3 that verifies whether biometric information matches registered information, and whether a user is correct. And an apparatus 2 that requests authentication requiring confirmation. The reader 1 and the device 2 that requests authentication are connected by any communication means (whether wireless or wired). The device 2 that requests authentication and the verification device 3 are connected by a communication channel (network) 4. The communication path 4 may be any communication means.

  There are various situations where it is necessary to confirm the identity of the person, for example, when using it instead of a signature such as a credit card, viewing restrictions based on the age of the WWW site, identity confirmation at a hospital, and the like. When receiving authentication in these various scenes, registering biometric information for each collation apparatus provided locally for each such scene is a great effort. In order to receive authentication, collation is impossible unless biometric information is registered in advance in each collation device. Therefore, it is very convenient to be able to cope with collation in every scene by registering biometric information once. In the present invention, in order to realize this, biometric information is registered in advance, and the verification device 3 that performs verification processing when a verification request is made and the device 2 that requests authentication are clearly separated. It is only necessary that the two are connected by the network 4 and can communicate with each other. Since communication between the two is encrypted, the network 4 may be a network with low confidentiality such as the Internet.

  In addition, when authentication is performed in such many places, it is conceivable that an unauthorized reading device is used to acquire a user's biometric information and an abuser appears. In order to avoid this, in the present invention, the device 2 that requires authentication and the reading device 1 are also clearly separated. It is only necessary that the two are connected by the network 4 and can communicate with each other. Since the communication between the two is encrypted, the network 4 may be a network with low confidentiality such as the Internet.

  FIG. 2 is a block diagram illustrating a configuration of the reading device 1. The reading device 1 includes a biological information acquisition unit 11, an identification information conversion unit 12, a processing unit 14, a communication processing unit 15, and an information recording unit 16. The reading device 1 is assumed to be possessed by each user. For example, the reading device 1 may have any form such as a PDA (Personal Digital Assistance), a notebook computer, a mobile phone, or a card.

  In FIG. 2, the biometric information acquisition unit 11 is a part that reads the biometric information of the user. The identification information conversion unit 12 extracts biological information necessary for identification from the biological information read by the biological information acquisition unit 11. The processing unit 14 controls the overall operation of the reading apparatus 1. The processing procedure will be described in detail with reference to FIG. The communication processing unit 15 performs communication processing with the device 2 that requests authentication. The information recording unit 16 holds the user ID of the user who owns the reading device 1, the public key PK3 of the verification device 3, and the secret key SK1 of the reading device 1. The public key PK3 is stored in advance as issued from the verification device 3. The secret key SK1 is prepared in advance by the user.

  FIG. 3 is a block diagram showing the configuration of the collation device 3. The verification device 3 includes a biometric information verification processing unit 32, a processing unit 34, a communication processing unit 35, and an information recording unit 36. The biometric information collation processing unit 32 performs a process of collating whether or not the sent biometric information belongs to a regular user stored in the information recording unit 36 in advance. The processing unit 34 controls the overall operation of the verification device 3. The processing procedure will be described in detail with reference to FIG. The communication processing unit 35 performs communication processing with the device 2 that requests authentication. The information recording unit 36 includes the set data of the user ID, the biometric information, and the public key PK1 for each user, the set data of the device ID and the public key PK2 for each device 2 that requests each authentication, and the secret of the verification device 3 Holds key SK3 (corresponding to public key PK3). For each user, a user ID (identifier for uniquely identifying the user), biometric information, and public key PK1, a user ID is assigned to each user who uses the system in advance, and biometric information and public key PK1 are used by the user. Store what you get from. The public key PK1 corresponds to the secret key SK1. The device ID and public key PK2 for each device 2 that requests each authentication are assigned in advance to each device 2 that requests each authentication that uses this system, and are disclosed to each device 2 that requests each authentication. Obtain and store the key PK2. When the same user has a plurality of reading devices 1, a different user ID, secret key SK1, and public key PK1 may be used for each reading device.

  FIG. 4 is a block diagram illustrating a configuration of the device 2 that requests authentication. The device 2 that requests authentication includes a processing unit 24, a communication processing unit 25, and an information recording unit 26. The processing unit 24 controls the overall operation of the device 2 that requests authentication. The processing procedure will be described in detail with reference to FIG. The communication processing unit 25 performs communication processing between the reading device 1 and the verification device 3. The information recording unit 26 holds a device ID that identifies the device 2 that requests the main authentication, a secret key SK2 of the device 2 that requests the main authentication, and a public key PK3 of the verification device 3. As the device ID, an ID assigned in advance from the collation device 3 side is stored. The secret key SK2 is a secret key generated in advance by the device 2 that requests the main authentication, and corresponds to the public key PK2. The public key PK3 of the verification device 3 is acquired from the verification device 3 and stored in advance.

  Hereinafter, the flow of authentication processing in the authentication system described with reference to FIGS. 1 to 4 will be described with reference to FIG. 5 (FIGS. 5a to 5d).

  In step S <b> 1, first, in a situation where it is necessary to confirm the identity, the device 2 that requests authentication requests the reading device 1 for authentication processing. It is assumed that the user who owns the reading device 1 places the reading device 1 in a state where it can communicate with the device 2 that requests authentication. For example, if the reading device 1 is a card, it is inserted into a predetermined insertion slot of the device 2 that requires authentication, or placed at a predetermined position (when a wireless communication function such as Bluetooth is provided). Is to do.

  In step S2, upon receiving the request, the reading device 1 starts an authentication process. First, in step S3, the user ID and the secret key SK1 of the reading device 1 are read from the information recording unit 16, and the user ID is digitally signed with SK1. Thereby, the collation apparatus 3 can confirm later whether the user ID has been altered or whether the information transmission source is the correct user ID. In step S4, subsequently, the public key PK3 of the verification device 3 is read from the information recording unit 16, and the user ID digitally signed in step S3 is encrypted with PK3. As a result, the user other than the verification device 3 does not know which user is currently performing the authentication process. Note that the process of step S4 is not essential. If there is no problem even if it is known which user is currently performing authentication processing, there is no need to perform encryption processing. In step S5, subsequently, the user ID processed up to step S4 is transmitted to the verification device 3. Communication with the verification device 3 is performed via the device 2 that requests authentication.

  In the verification device 3, in step S6, the secret key SK3 is read from the information recording unit 36, and the received information is decrypted. Note that this processing is not necessary if the data is not encrypted in step S4. Next, in step S7, the public key PK1 of the reading device 1 is specified based on the user ID included in the decrypted information. As shown in FIG. 3, the collation device 3 holds user IDs of a large number of users (users using this system), biometric information used for collation, and public keys. Information about other users may be held. In step S8, it is confirmed that the user ID is not altered using the specified public key PK1. By using a digital signature using a public key infrastructure technology of PKI (Public Key Infrastructure), it is possible to confirm that the received information has not been altered and to identify the transmission source of the received information.

  Subsequently, in step S9, a random common key CK is generated. The common key CK is generated so as to be different for each authentication. Therefore, it is possible to prevent impersonation due to replay attack. Since this common key CK is a common key used only for communication between the verification device 3 and the user ID, in step S10, the generated common key CK and the user can be obtained from the user ID later. Record the ID as a set. In step S11, the common key CK is digitally signed with the secret key SK3. As a result, it is possible to identify the sender of the information and check whether the information has been altered. In step S12, the digitally signed common key CK is encrypted with the public key PK1 of the reading device 1. Since the information encrypted with the public key PK1 can be decrypted only to those having the secret key SK1, only the reading device 1 can obtain the information encrypted here. In step S13, the signed and encrypted common key CK is transmitted to the reading device 1.

  In step S14, the reader 1 decrypts the received information using the secret key SK1. In step S15, using the public key PK3 of the verification device 3, it is confirmed that the received content (common key CK) has not been altered. Since only the collation device 3 having the secret key SK3 can sign this, impersonation on the collation device side can be prevented. If the common key CK is not altered, information necessary for biometric authentication is acquired from the biometric information acquisition unit 11 in step S16, and biometric information necessary for identification is extracted by the identification information conversion unit 12. The information acquired by the biological information acquisition unit 11 can be any biological information that can be identified by an individual. For example, fingerprints, irises, vein patterns, etc. can be considered. Next, in step S17, the biometric information acquired in step S16 is digitally signed using the secret key SK1. Thereby, it can be assured that there is no alteration in the biometric information and that the transmission source is the reading device 1. In step S18, the biometric information digitally signed is encrypted with the common key CK.

  Here, only the collation device 3 that generated CK and the reading device 1 having the secret key SK1 know the common key CK. Since the common key CK is transmitted after being encrypted with the public key PK1, the common key CK cannot be known except for the reading device 1 that can decrypt it. Therefore, the information encrypted with the common key CK can be decrypted only by the reading device 1 and the collation device 3, and the biological information can be prevented from being stolen by eavesdropping. Further, since the common key CK is different every time authentication is performed, it is possible to prevent impersonation on the reading device side due to replay attack.

  Subsequently, in step S19, the user ID encrypted with the public key PK3, the signature, and the encrypted biometric information are combined and transmitted to the apparatus 2 that requests authentication. In addition, as described in step S4, if there is no problem even if it is known which user is currently performing the authentication process, it is not necessary to perform the encryption process.

  In the device 2 that requests authentication, the information transmitted from the reading device 1 is received in step S20. In step S21, the secret key SK2 is read from the information recording unit 26, and the received information is digitally signed using the secret key SK2. As a result, it can be assured that the information has been transmitted from the device 2 requesting authentication and that the information has not been altered. In step S22, the digitally signed information and the device ID are combined and transmitted to the verification device 3. At this time, if there is a problem when it is known which authentication device 2 is performing authentication processing, the device ID may be encrypted with the public key PK3 of the verification device 3.

  In step S23, the verification device 3 specifies the public key PK2 of the device 2 that requests authentication based on the device ID of the received information. If the device ID is encrypted in step S22, the device ID must be decrypted with the secret key SK3 before this process. The collation device 3 holds information on a large number of devices. These pieces of information must include a device ID for uniquely identifying the device and the public key of the device, but may include other information. In step S24, using the specified public key PK2, it is confirmed that the received information is not altered. At the same time, it can be confirmed that the transmission source is the device 2 that requests authentication having the secret key SK2. In step S25, the user ID is decrypted with the secret key SK3. If the user ID is not encrypted in step S19, this process is not necessary.

  In step S26, the common key CK recorded in step S10 is acquired based on the user ID. In step S27, the biometric information is decrypted using the common key CK. In step S28, the public key PK1 of the reading device 1 is specified based on the user ID. In step S29, it is confirmed whether there is any alteration in the biometric information using the public key PK1. At the same time, it can be confirmed that the transmission source of the biometric information is the reading device 1 having the secret key SK1. If it is confirmed that there is no alteration in the biometric information, in step S30, the biometric information registered based on the user ID is read from the information recording unit 36, and the biometric information is collated. In step S31, information notifying the collation result is digitally signed with the secret key SK3 and transmitted to the apparatus 2 that requests authentication.

  In the device 2 that requests authentication, in step S32, the public key PK3 is acquired from the information recording unit 26, and it is confirmed that the received information is not altered. As a result of the collation in the collation device 3, if the user is authenticated as a legitimate user, the reader 1 may be processed as a legitimate user. If the authentication is not successful, a process corresponding to the case where the authentication is not successful may be performed.

  FIG. 6 is a schematic diagram showing a trust relationship between the devices in the present embodiment. A person who receives the authentication possessing the reading device 1 trusts the certificate authority 3 that operates the verification device 3. A person who needs to confirm whether or not the person who operates the apparatus that requires authentication trusts the certificate authority 3 that operates the verification apparatus 3 in the same manner. On the other hand, there is generally no trusting relationship between a person who is authenticated and a person who needs to confirm whether or not the person is authentic. This is because there are cases where the person who receives the authentication receives the service provided by the person who needs to check whether the person is the first person or not. However, even in such a relationship, according to the authentication system of the present embodiment, it is possible to perform mutual authentication via the certificate authority.

Schematic diagram showing a configuration example of the present invention Configuration diagram showing configuration of reader Configuration diagram showing the configuration of the verification device Configuration diagram showing the configuration of a device that requests authentication Flowchart showing the outline of authentication processing procedure (Part 1) Flow chart showing the outline of authentication processing procedure (Part 2) Flowchart showing the outline of authentication processing procedure (Part 3) Flowchart showing the outline of authentication processing procedure (Part 4) Schematic diagram showing the trust relationship between devices

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Reading apparatus, 2 ... Apparatus which requests | requires authentication, 3 ... Verification apparatus, 4 ... Communication path, 5 ... Biometric information to authenticate, 11 ... Biometric information acquisition part, 12 ... Identification information conversion part, 14 ... Processing part, 15 ... Communication processing unit, 16 ... Information recording unit, 24 ... Processing unit, 25 ... Communication processing unit, 26 ... Information recording unit, 32 ... Biometric information matching processing unit, 34 ... Processing unit, 35 ... Communication processing unit, 36 ... Information Recording unit.

Claims (1)

An authentication system using biometric information,
A reading device possessed by a user who is authenticated, a device that requests authentication, and a verification device that performs authentication,
The reader is
Means for obtaining biometric information;
An information recording means for storing a user ID which is an identifier for identifying a user, a public key PK3 of the verification device, and a secret key SK1 of the reading device;
Communication processing means;
Processing means for controlling the overall operation of the reader,
The device that requests the authentication is:
Information recording means for storing a device ID for specifying a device requesting authentication, a secret key SK2 of the device requesting authentication, and a public key PK3 of the verification device;
Communication processing means;
Processing means for controlling the overall operation of the device that requires authentication, and
The verification device is
Information recording means storing user ID, biometric information and public key PK1 for each user, device ID and public key PK2 for each device requesting each authentication, and secret key SK3 of the verification device ,
Biometric information matching processing means for checking whether or not given biometric information has been registered in the information recording means;
Communication processing means;
Processing means for controlling the overall operation of the verification device,
When the device requesting authentication requests authentication from the reading device,
The signature data obtained by digitally signing the user ID with the secret key SK1 and the user ID are transmitted from the reading device to the verification device,
The verification device identifies the public key PK1 corresponding to the received user ID from the information recording means, confirms that the user ID is not altered from the received signature data, generates a random common key CK, A user ID and a common key CK are recorded as a set, the common key CK is digitally signed with the secret key SK3, and the signature data and the common key CK encrypted with the public key PK1 are transmitted to the reading device. ,
The reading device decrypts the received encrypted common key CK with the secret key SK1, confirms that the common key CK has not been altered from the received signature data, and then obtains the biometric information by the user. A device that requests the authentication by reading the biometric information, digitally signing the biometric information with the secret key SK1, encrypting the biometric information with the common key CK, and user ID, signature data, and encrypted biometric information Send
The device requesting the authentication digitally signs the received information with a secret key SK2, and transmits the received information, signature data, and device ID to the verification device,
The verification device identifies the public key PK2 corresponding to the received device ID from the information recording means, confirms that the information is not altered from the received signature data, and corresponds to the user ID included in the received information To obtain the common key CK, decrypt the encrypted biometric information included in the received information with the common key CK, identify the public key PK1 corresponding to the user ID, and use the public key PK1 to Confirm that the information has not been altered, verify the acquired biometric information and the biometric information registered in the information recording means, and request the authentication by attaching a digital signature to the verification result with the private key SK3 To the device,
The authentication system using biometric information, wherein the authentication requesting device uses the public key PK3 to confirm that the received verification result has not been altered, and acquires the verification result.

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