JP2010239294A - Electronic signature system, electronic signature generating apparatus, electronic signature verifying apparatus, and, program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve electronic signature utilizing biometrics information. <P>SOLUTION: First encrypted biometrics information, a hash value of electronic data to be signed and identification information of a signer are received and if the biometrics information is matched with preaccumulated one, a signature key is generated using time stamp information, prestored private information and the biometrics information. A signature value generated using the signature key for the hash value, second encrypted biometrics information and time stamp information are returned. The returned signature value, second encrypted biometrics information and time stamp information are received together with a hash value of electronic data to be verified and the identification information of the signer. If the biometrics information is matched with preaccumulated one, a signature key is generated using the time stamp information, prestored private information and the biometrics information. It is then returned whether or not the signature value generated using the signature key for the hash value is matched with the received signature value. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electronic signature system, an electronic signature generation device, an electronic signature verification device, and a program.

  At present, as a method for verifying the signer's identification and non-falsification property with respect to electronic data, an electronic signature method using a public key encryption method using two encryption keys, a secret key and a public key, is the most common.

  In an electronic signature using a public key cryptosystem, a mechanism is required that allows the verifier to verify that the signer himself has the private key used for the electronic signature. Here, PKI (Public Key Infrastructure) is currently the most common. In this method, a certificate authority called CA (Certificate Authority) issues a “public key certificate” that proves the owner of a private key / public key pair. The verifier can recognize that the owner of the public key is the signer himself / herself by verifying the public key certificate.

JP 2008-172338 A JP 2006-270342 A JP 2005-123883 A

However, this public key cryptosystem and PKI have the following problems.
・ A public key pair must be created and the private key must be managed securely by the user. The user needs to work only on the terminal storing the secret key, and there is a risk of theft and leakage when carrying the secret key.
・ If you obtain a private key, anyone other than you can sign it. That is, since this secret key is electronic data, there is a risk that it will be transferred or rented to others, and there is a possibility that a person other than the proper owner may sign.
In the PKI method, it is necessary to set a valid period and issue a revocation information list (CRL) for issued certificates, which makes operation management complicated.

  Also, in the physical world, since the person performs a special operation such as directly signing or pressing a seal for signing, it is possible to obtain a feeling of “signing”. However, since an electronic signature is a logical world, an operation using a keyboard or a mouse is the same operation as other work such as document creation, and thus there is a problem that it is difficult to obtain an actual feeling for the act of “signing”.

  Furthermore, with an electronic signature, it is possible to check who is the signer and whether the signed document has not been tampered with after signature, but there is no guarantee as to when it was signed. As a mechanism for guaranteeing this “when”, there is a method of giving a signature for a time stamp. In this case, it is necessary to perform a digital signature and a signature for a time stamp twice.

  In order to solve the above problems, the present invention does not use a public key cryptosystem that is currently the mainstream as a method for signing electronic data, but uses a digital signature method that utilizes biometric information such as a fingerprint. Identification of the person, time and non-falsification of the data.

  That is, the electronic signature system according to the present invention includes biometric information storage means for storing the biometric information of the signer read by the biometric information reading means and the identification information of the signer in association with each other, and biometric information reading The first encrypted biometric information obtained by encrypting the biometric information of the signer read by the means, the hash value of the electronic data for which the electronic signature is generated, and the identification information of the signer are received from the terminal. Then, whether the biometric information obtained by decrypting the first encrypted biometric information matches the biometric information stored in the biometric information storage unit corresponding to the received signer identification information. The signature generation authentication means to be judged matches the signature generation authentication means Then, a signature key is generated using the generated time stamp information, secret information stored in advance, and biometric information obtained by decrypting the first encrypted biometric information, and the signature key is used to generate the signature key. The signature value generated for the hash value, the second encrypted biometric information obtained by encrypting the biometric information obtained by decrypting the first encrypted biometric information, and the time stamp information are returned to the terminal. The signature generation means, the signature value returned to the terminal, the second encrypted biometric information, the time stamp information, the hash value of the electronic data to be verified by the electronic signature, and the identification information of the signer Corresponding to the biometric information obtained by decrypting the second encrypted biometric information and the received signer identification information. If the biometric information stored in the biometric information storage means matches with the signature verification authentication means and the signature verification authentication means matches, the received time stamp information and the pre-stored A signature key generated using the signature information and the biometric information obtained by decrypting the second encrypted biometric information, and the signature value generated for the hash value using the signature key; Signature verification means for returning to the terminal whether or not the received signature value matches.

  The electronic signature generation apparatus according to the present invention includes biometric information storage means for storing the biometric information of the signer read by the biometric information reading means and the identification information of the signer in association with each other, and biometric information The first encrypted biometric information obtained by encrypting the signer's biometric information read by the reading means, the hash value of the electronic data for which the electronic signature is to be generated, and the identification information of the signer are received from the terminal. When received, the biometric information obtained by decrypting the first encrypted biometric information matches the biometric information stored in the biometric information storage means corresponding to the received signer identification information. If the authentication means for determining whether the authentication means matches, the generated time A signature key generated using the signature information, the secret information stored in advance, and the decrypted biometric information, the signature value generated for the hash value using the signature key, and the decrypted biometric Signature generating means for returning the second encrypted biometric information obtained by encrypting the metrics information and the time stamp information to the terminal is provided.

  The electronic signature verification apparatus according to the present invention comprises biometric information storage means for storing the signer's biometric information read by the biometric information reading means and the signer's identification information in association with each other, and a signature value. Receiving the encrypted biometric information, the time stamp information, the hash value, and the signer identification information from the terminal, the biometric information obtained by decrypting the encrypted biometric information, and the received signer identification Authentication means for determining whether or not the biometric information stored in the biometric information storage means corresponding to the information matches, and if the authentication means matches, the time stamp information and prestored secret information; Generating a signature key using the decrypted biometric information and using the signature key A signature value generated for the hash value, and wherein whether the signature value thus received matches that and a signature verification unit to reply to the terminal.

The present invention has a function of performing an electronic signature using biometric information as a signature key. The present invention solves the problem as follows.
-Since biometrics information is used as a signature key, it is not necessary for the user to generate / manage keys (especially secret key management).
-Since biometric information is used as a signature key, it is not necessary to have electronic data such as a public key certificate at the time of signature and verification.
-Since biometric information is used as a signature key, signature data cannot be generated by anyone other than the principal.
・ Since biometrics information is used as a signature key, it is not necessary to issue a certificate, and complicated operational management such as setting a validity period and issuing a revocation information list (CRL) is not required. .
・ Because biometrics information is used as a signature key, there is an act of reading biometrics information, and there is a strong feeling of using personal information. Cheap.
・ Also, when signing key is generated from biometric information, by including time information, it is possible to prove the signer, time and non-falsification with a single signature.

It is a figure showing the structure of a signature verification system, a signer terminal, and a verifier terminal. It is a figure showing the flow of information in signature and verification. It is a figure showing a signature data generation flow. It is a figure showing a signature data verification flow. It is a figure showing the example of signature data.

  Hereinafter, embodiments of the present invention will be described in detail.

<Configuration of Example>
The present invention reads a signer's biometric information, requests a signer terminal 10 to request generation of an electronic signature, a verifier terminal 20 to request verification of an electronic signature, and manages, signs and verifies biometric information. The signature verification system 30 is composed of three components.

The signer terminal 10 has the following functions.
-Function to obtain signer's biometric information-Function to send information necessary for signature generation to signature verification system 30

The verifier terminal 20 has the following functions.
A function for sending information necessary for signature verification to the signature verification system 30

  The signature verification system 30 includes a signature subsystem 31 that performs signature, a verification subsystem 32 that performs verification, and biometric information storage means 33 that stores biometric information.

The signature subsystem 31 has the following functions.
-Function to authenticate signer from received biometric information-Function to generate key from received biometric information-Function to generate signature for electronic data

The verification subsystem 32 has the following functions.
・ Function to authenticate signer from received biometric information ・ Function to generate key from received biometric information ・ Function to verify signature of electronic data

  In the signature verification system 30, a secret key for signature, a public / private key pair for verification, secret information (such as a random number) of the signature verification system 30, and biometric information of the signer are registered in advance. Stored. In addition, the signer terminal 10 is pre-registered and stored with a signature public key for the signature verification system 30.

<Operation of Example>
Next, the operation of the embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 2 represents the information flow in signature and verification.
First, the user registers his / her biometric information in the signature verification system 30 in advance. The biometric information can be a fingerprint or an iris. Here, in the registration to the signature verification system 30, user information (additional information such as name and affiliation) may be registered together with biometric information. The signature verification system 30 stores the registered information in the biometric information storage unit 33 and issues a unique ID (hereinafter referred to as a user ID) so that the user and the registered information are uniquely linked.

  Next, the signature data generation operation will be described with reference to FIG.

  The user selects electronic data to be signed (hereinafter referred to as signature target data). Subsequently, the user inputs his / her fingerprint information through the biometric information reading means 11 (S101). The signer terminal 10 encrypts the read biometric information using the signature public key of the signature verification system 30 (hereinafter referred to as encrypted biometric information 1) (S102).

  Subsequently, the signer terminal 10 obtains a hash value (hereinafter, hash data) for the signature target data using a hash function (S103).

  When the encrypted biometric information 1 and the hash data are obtained, the signer terminal 10 obtains signer information from the user. As the signer information, a user ID issued for uniquely linking the information of the biometric information storage means 33 in the signature verification system 30 and the signer information is registered. In addition, additional information such as the name and affiliation of the signer may be input.

  After inputting the signer information, the signer terminal 10 obtains information on the signature verification system 30 (hereinafter referred to as signature verification system information) in which the biometric information is registered from the user (S104). As shown in the signature verification system information column of FIG. 5, the signature verification system information includes a hash algorithm of electronic data, a signature method, a signature verification system name, a verification request destination, a hash value of signature verification system information, and the like. The signature verification system information is registered in advance in the signer terminal 10, and the signer terminal 10 obtains the information of the signature verification system 30 by selecting the corresponding signature verification system 30 from a plurality of signature verification system information. A method is possible.

  When the signature verification system information is input, the signer terminal 10 transmits the encrypted biometric information 1, hash data, and signer information to the signature subsystem 31 of the signature verification system 30 (S105).

  Upon receiving the encrypted biometric information 1, hash data, and signer information, the signature subsystem 31 first decrypts the encrypted biometric information 1 using the signature private key of the signature verification system 30 (S106). . Subsequently, the user ID is acquired from the signer information, and the corresponding biometric information is acquired from the biometric information storage means 33 (S107). Then, using the decrypted biometric information and the biometric information acquired from the biometric information storage means 33, authentication is performed as to whether the person is the signer (S108). As a result of authentication, if it is determined that the person is not the signer, the process is terminated.

  If it is determined as a result of the authentication that the user is the signer, the signature subsystem 31 acquires time stamp information and secret information of the signature verification system 30 (hereinafter, signature verification system secret information) (S109). Subsequently, a signature key is generated from the acquired time stamp information, signature verification system secret information, and decrypted biometric information (S110). As a signing key generation method, a method of using information obtained by combining the three pieces of information as it is, a method of using information processed using a hash function (MD5, SHA-1), or the like can be used.

  After generating the signature key, the hash data is signed using the signature key to obtain a signature value (S111). As a signature method, a method using a hash-based message authentication code (HMAC-SHA-512) or the like is possible. When the signature value is generated, the signature subsystem 31 encrypts the decrypted biometric information using the public key for verification of the signature verification system 30 (hereinafter referred to as encrypted biometric information 2) (S112). Then, the encrypted biometric information 2, the time stamp information, and the signature value are returned to the signer terminal 10 (S113).

  Finally, the signer terminal 10 combines the signature value, time stamp information, encrypted biometric information 2, signer information, and signature verification system information, calculates a hash value using a hash function to prevent tampering, Signature data (see FIG. 5) is generated.

  Next, the signature data verification operation will be described with reference to FIG.

  The verifier terminal 20 first combines the signature value, time stamp information, encrypted biometric information 2, signer information, and signature verification system information to confirm that the signature data (see FIG. 5) has not been tampered with. A hash value is acquired for the portion ((b) of FIG. 5) using a hash algorithm of signature data, and matched with the hash value described in the signature data (S201). If they match, it is determined that the file has not been tampered with and the next operation is performed. If they do not match, it is determined that they have been tampered with, and the operation is terminated.

  Subsequently, in order to check whether the acquired signature verification system information has been tampered with, the hash algorithm of the signature verification system information is used for the portion other than the hash value of the signature verification system information ((a) in FIG. 5). The hash value is acquired (S202) and matched with the hash value described in the signature verification system information (S203). If they match, it is determined that the file has not been tampered with and the next operation is performed. If they do not match, it is determined that they have been tampered with, and the operation is terminated.

  Next, the verifier terminal 20 acquires a signature value, time stamp information, encrypted biometric risk information 2, and signer information from the signature data (S204 to 207). Further, a hash value (hash data) is obtained for the electronic data by using a hash algorithm of the electronic data described in the signature verification system information (S208). Then, verification request destination information for requesting verification is acquired from the signature verification system information, and the verification request destination verifies the signature value, time stamp information, encrypted biometric information 2, hash data, and signer information. 32 (S209).

  When the verification subsystem 32 receives the signature value, the time stamp information, the encrypted biometric information 2, the hash data, and the signer information, first, the encrypted biometric information using the verification private key of the signature verification system 30 is received. 2 is decrypted (S210). Subsequently, the user ID is acquired from the signer information, and the corresponding biometric information is acquired from the biometric information storage means 33 (S211). Then, using the decrypted biometric information and the biometric information acquired from the biometric information storage means 33, authentication is performed as to whether or not the signer is himself (S212). As a result of authentication, if it is determined that the person is not the signer, the process is terminated.

  As a result of authentication, when it is determined that the user is the signer, the signature verification system 30 acquires signature verification system secret information (S213). Subsequently, a signature key is generated from the time stamp information, the signature verification system secret information, and the decrypted biometric information (S214). Further, the hash data is signed using the signature key to obtain a signature value (S215). The signature value obtained here is matched with the sent signature value (S216), and if they match, it is determined that the signature has not been tampered with, and a response to the verifier terminal 20 is sent back to the verifier terminal 20 (S217). If they do not match, it is determined that the file has been tampered with, and a verification failure is returned to the verifier terminal 20 (S218). In this reply, it is also possible to notify the information on the signer to the verifier terminal 20 side by giving the signer additional information from the signature verification system 30 side.

  The present invention can be applied to fields in which it is necessary to detect falsification of electronic data, to authenticate the creator, and to specify the time of signature.

  DESCRIPTION OF SYMBOLS 10 ... Signer terminal, 11 ... Biometric information reading means, 20 ... Verifier terminal, 30 ... Signature verification system, 31 ... Signature subsystem, 32 ... Verification subsystem, 33 ... Biometrics information storage means

Claims (8)

Biometric information storage means for storing the biometric information of the signer read by the biometric information reading means and the identification information of the signer in association with each other;
First encrypted biometric information obtained by encrypting the biometric information of the signer read by the biometric information reading means, a hash value of electronic data for which an electronic signature is generated, and identification information of the signer Is received from the terminal, the biometric information obtained by decrypting the first encrypted biometric information matches the biometric information stored in the biometric information storage means corresponding to the received signer identification information. A signature generation authentication means for determining whether or not to perform;
When the authentication means for signature generation matches, a signature key is generated using the generated time stamp information, prestored secret information, and biometric information obtained by decrypting the first encrypted biometric information, A signature value generated for the hash value using the signature key; second encrypted biometric information obtained by encrypting biometric information obtained by decrypting the first encrypted biometric information; and the time stamp Signature generating means for returning information to the terminal;
When receiving from the terminal the signature value, the second encrypted biometric information, the time stamp information, the hash value of the electronic data subject to electronic signature verification, and the signer identification information, the signature value returned to the terminal is received. Signature verification for determining whether biometric information obtained by decrypting the encrypted biometric information of 2 matches biometric information stored in the biometric information storage means corresponding to the received signer identification information. Authentication means,
When the authentication means for signature verification matches, a signature key is generated using the received time stamp information, the previously stored secret information, and biometric information obtained by decrypting the second encrypted biometric information And signature verification means for returning to the terminal whether the signature value generated for the hash value using the signature key matches the received signature value;
An electronic signature system comprising: The first encrypted biometric information is encrypted using a first public key;
The decryption of the first encrypted biometric information is performed using a first secret key corresponding to the first public key,
Encryption of biometric information obtained by decrypting the first encrypted biometric information is performed using a second public key,
The electronic signature system according to claim 1, wherein the decryption of the second encrypted biometric information is performed using a secret key corresponding to the second public key. Biometric information storage means for storing the biometric information of the signer read by the biometric information reading means and the identification information of the signer in association with each other;
First encrypted biometric information obtained by encrypting the biometric information of the signer read by the biometric information reading means, a hash value of electronic data for which an electronic signature is generated, and identification information of the signer Is received from the terminal, the biometric information obtained by decrypting the first encrypted biometric information matches the biometric information stored in the biometric information storage means corresponding to the received signer identification information. Authentication means for determining whether or not to do;
If the authentication means agrees, a signature key is generated using the generated time stamp information, pre-stored secret information, and the decrypted biometric information, and the signature key is used for the hash value. Signature generating means for returning the generated signature value, the second encrypted biometric information obtained by encrypting the decrypted biometric information, and the time stamp information to the terminal;
An electronic signature generation apparatus comprising: The first encrypted biometric information is encrypted using a first public key;
The decryption of the first encrypted biometric information is performed using a first secret key corresponding to the first public key,
4. The electronic signature generation apparatus according to claim 3, wherein the decryption of the decrypted biometric information is performed using a second public key. Biometric information storage means for storing the biometric information of the signer read by the biometric information reading means and the identification information of the signer in association with each other;
When a signature value, encrypted biometric information, time stamp information, hash value, and signer identification information are received from the terminal, biometric information obtained by decrypting the encrypted biometric information, and the received signature Authentication means for determining whether or not the biometric information stored in the biometric information storage means corresponding to the identification information of the person matches,
When the authentication means agrees, a signature key is generated using the time stamp information, pre-stored secret information, and the decrypted biometric information, and generated for the hash value using the signature key Signature verification means for returning to the terminal whether or not the received signature value matches the received signature value;
An electronic signature verification apparatus comprising: The encrypted biometric information is encrypted using a public key,
The electronic signature verification apparatus according to claim 5, wherein the decryption of the encrypted biometric information is performed using a secret key corresponding to the public key. A computer of an electronic signature generation apparatus comprising biometric information storage means for storing biometric information of a signer read by biometric information reading means and the identification information of the signer in association with each other.
First encrypted biometric information obtained by encrypting the biometric information of the signer read by the biometric information reading means, a hash value of electronic data for which an electronic signature is generated, and identification information of the signer Is received from the terminal, the biometric information obtained by decrypting the first encrypted biometric information matches the biometric information stored in the biometric information storage means corresponding to the received signer identification information. Authentication means for determining whether to
If the authentication means agrees, a signature key is generated using the generated time stamp information, pre-stored secret information, and the decrypted biometric information, and the signature key is used for the hash value. Signature generating means for returning the generated signature value, the second encrypted biometric information obtained by encrypting the decrypted biometric information, and the time stamp information to the terminal;
Program to function as. A computer of an electronic signature verification device comprising biometric information storage means for storing the biometric information of the signer read by the biometric information reading means and the identification information of the signer in association with each other.
When a signature value, encrypted biometric information, time stamp information, hash value, and signer identification information are received from the terminal, biometric information obtained by decrypting the encrypted biometric information, and the received signature Authentication means for determining whether or not the biometric information stored in the biometric information storage means corresponding to the identification information of the person matches.
When the authentication means agrees, a signature key is generated using the time stamp information, pre-stored secret information, and the decrypted biometric information, and generated for the hash value using the signature key Signature verification means for returning to the terminal whether or not the received signature value matches the received signature value;
Program to function as.

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