JP2011077933A - Digital signature verifying apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital signature verifying apparatus performing multiple digital signature verifications at high speed and with high reliability. <P>SOLUTION: A verification module 112 verifies validity of a digital certificate included in each of signature data and whether or not a digital signatured document is tampered and generates verification result data. A simplified verification module 113 performs a verification using past verification result data stored in a storage unit 11. A verification selecting module 115 selects a verification performed by the verification module 112 for signature data to be verified which are latest in the same digital signature document or for which corresponding verification information is not present, and for the other signature data, the verification by the simplified verification module 113 can be selected. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention stores an electronic signature document with an electronic signature and its verification result data, and upon receiving a verification request, verifies all signature data applied to the electronic signature document to generate verification result data, The present invention relates to an electronic signature verification apparatus that generates and outputs a verification result from verification result data.

  Conventionally, in an electronic signature system having an electronic signature server, a certificate authority, and a user terminal, the electronic signature server uses an electronic certificate issued to the user by the certificate authority when an electronic signature is requested from the user terminal. The electronic data was signed and stored.

  When accessing the stored electronic data from the user terminal, the user terminal transmits an electronic signature verification request signal to the electronic signature server. When the electronic signature server receives the electronic signature verification request signal, the electronic signature server receives the electronic signature verification request signal. Execute digital signature verification processing. When verifying an electronic signature, the electronic signature verification device issues this electronic certificate, including whether the electronic data has been tampered with, the issuer, owner, expiration date, and expiration of the electronic certificate used for the signature. Judgment is made using data obtained from the certificate authority, and the validity of the electronic data is confirmed.

  When electronic data is stored for a long period of time, a multiple electronic signature is used in which multiple digital signatures are applied from the innermost side to the outermost side in order of generation. In this case, the first electronic signature applied to the innermost side is applied to the electronic data, and the latest electronic signature applied to the outermost side from the electronic signature applied next is the previous signature. Is applied not only to the electronic data to which the electronic signature has been applied, but also to the electronic certificate used for the electronic signature previously applied and the revocation information for determining the validity thereof. Verification of electronic data with multiple electronic signatures shall be performed retrospectively from the outermost side of the electronic signature to the innermost side, checking the validity of the electronic certificate and checking whether the signature target has been tampered with. (For example, Patent Document 1).

JP 2008-300955 A

  However, verification of multiple electronic signatures requires a certain processing time to execute a series of processes for each electronic signature from the outermost side to the innermost side of the electronic signature, and is multiplexed. As a result, the processing load of the electronic signature verification apparatus increases, and the time until the electronic signature verification apparatus outputs the verification result is increased.

  An object of the present invention is to provide an electronic signature verification apparatus capable of performing multiple electronic signature verification at high speed and with high reliability.

  In order to solve this problem, the present invention provides an electronic signature document to which an electronic signature has been applied, a storage unit for storing the verification result data, and all signature data applied to the electronic signature document upon receipt of a verification request. An electronic signature verification apparatus having a control unit that generates verification result data by verifying, generates a verification result from the verification result data, and outputs the verification result. Consists of at least verification data including signature data including the signature time to be generated and information capable of determining the validity of the electronic certificate used for the signature, and the control unit includes an electronic certificate included in each signature data. A verification means for generating verification result data by verifying the validity of the certificate and the presence or absence of falsification of the electronic signature document, and a simple verification method for verifying using the past verification result data stored in the storage unit If the signature data to be verified is the latest in the same electronic signature document or the corresponding verification information does not exist, the verification by the verification means is selected, and the other signature data is verified by the simple verification means. There is provided an electronic signature verification device comprising verification selection means for enabling selection.

  In such an electronic signature verification apparatus, the simple verification means uses the verification information to verify the validity of the electronic certificate included in the corresponding signature data and whether or not the electronic signature document has been altered if the past verification result data has been altered. It is preferable to generate verification result data by verifying.

  In the electronic signature verification apparatus, when the control unit receives a signature request designating the electronic signature document, if the electronic signature document does not have signature data, the control unit generates signature data for the electronic file using the electronic certificate of the signer. If there is already signature data in the digital signature document and there is no verification information corresponding to the signature data, the verification unit verifies and stores the verification result data in the storage unit. After the verification information is added to the electronic signature document, signature data for a predetermined signature object is generated using the electronic certificate of the signer and added to the electronic signature document, and the signature data has already been added to the electronic signature document. If there is verification information corresponding to the signature data, it is preferable to further include electronic signature means for verifying by the simple verification means and updating the verification result data.

  ADVANTAGE OF THE INVENTION According to this invention, the electronic signature verification apparatus which can perform multiple electronic signature verification at high speed and high reliability can be provided.

1 is a configuration diagram of an electronic signature system in which an electronic signature verification apparatus according to the present invention is used. It is a figure which shows the data structure of the electronic signature document area | region in the memory | storage part of an electronic signature server. It is a figure which shows the data structure of the verification result area | region in the memory | storage part of an electronic signature server. It is a figure which shows the data structure of the user information area | region in the memory | storage part of an electronic signature server. It is a flowchart of the process of the electronic signature server of FIG. 1 performed according to a signature request | requirement. It is a flowchart of the process of the electronic signature server of FIG. 1 performed according to a verification request | requirement.

An embodiment of an electronic signature verification apparatus according to the present invention will be described with reference to the drawings.
The electronic signature verification apparatus according to the present invention is effective if the signature data to be verified is the latest in the same electronic signature document or the corresponding verification information does not exist, and the validity of the electronic certificate included in each signature data In addition, the digital signature document is verified to check whether the digital signature document has been tampered with and used as verification result data, and the other signature data is a device that enables verification using past verification result data.

  FIG. 1 is a configuration diagram of an electronic signature system in which an electronic signature verification apparatus according to the present invention is used. The electronic signature system shown in FIG. 1 is applied to, for example, an in-house system, and includes an electronic signature server 1 as an electronic signature verification device, a user terminal 2, a certificate authority 3, and a communication network 4. In the following description, “electronic signature” is also simply referred to as “signature”, and “electronic certificate” is also simply referred to as “certificate”.

  The electronic signature server 1 realizes functions such as verification for all signature data applied to the electronic signature document. For this purpose, the electronic signature server 1 communicates with the storage unit 11, the control unit 12 that performs various controls of the electronic signature server 1, the timing unit 13, and the user terminal 2 and the certificate authority 3 through the communication network 4. A communication interface (I / F) unit 14.

  The storage unit 11 includes at least one of a rewritable nonvolatile memory such as a flash memory and an EEPROM, a magnetic hard disk, a rewritable optical disk, and a drive thereof. The storage unit 11 includes an electronic signature document area, a verification result area, and a user information area. The storage unit 11 stores various control information used by the control unit 12.

  FIG. 2 is a diagram showing the data structure of the electronic signature document area in the storage unit of the electronic signature server. The electronic signature document is composed of an electronic file to be stored, signature data as a result of applying the signature, and verification information for confirming the validity of the electronic certificate used for the signature. In particular, when multiple digital signatures are applied to a storage target, signature data and verification information are generated each time an electronic signature is applied to an electronic file, and these signature data and verification information are stored in the storage unit 11.

  A group of data associated with an electronic signature document code described later is referred to as an electronic signature document. The electronic file is the original electronic document itself that is generated and stored by the user.

  The electronic signature document code is a unique code that is given when the electronic signature server 1 receives an electronic file from the outside by the communication I / F unit 14 and stores it in the storage unit 11 for the first time. Thereafter, when a digital signature document is signed in a superimposed manner, the digital signature document code is used as a reference for association. Such an electronic signature document code is given by the electronic signature system when the electronic file is stored in the storage unit 11.

  The signature data includes the signer's electronic certificate, digital signature value, signature time, signer name, and the like used when applying the electronic signature. The signature data is generated every time an electronic signature is applied to the storage target.

  The verification information is information that forms a pair with the signature data, and is ground information for confirming the validity of the electronic certificate when the signature data is verified. That is, the signature data can be re-verified using the verification information. Specifically, the verification information includes an electronic certificate revocation list (CRL (Certificate Revocation List)) at the time of verification and the electronic certificate of the certificate authority 3 that issued the CRL.

  FIG. 2 shows an electronic signature document signed up to the fourth generation. In this case, first, signature data “a” to be a first generation signature is generated for an electronic file as a signature target, and an electronic signature document is generated. Next, when a new signature is applied repeatedly, verification information a used when re-verifying the signature data a is generated, the electronic file, the signature data a, and the verification information a are set as new signature targets. Signature data b to be a generation signature is generated. Similarly, signature data b and verification information b of the second generation signature in addition to the electronic file, signature data a and verification information a are set as signature targets, and signature data c of the third generation signature is generated. In addition to the electronic file, the signature data a, the verification information a, the signature data b, and the verification information b, the signature data c of the third generation signature and the verification information c are set as signature targets, and signature data d of the fourth generation signature is generated. Is done.

  Here, the fourth generation signature is the newest signature, which is referred to as the latest signature data. When the electronic signature document is further signed, the latest signature data verification information is generated, the latest signature data and the generated verification information are added to the signature target, new signature data is generated, and a new signature data is generated. The signature data is added to the electronic signature document, and the electronic signature document is updated. Note that the above-mentioned signature generations such as the first generation, the second generation, etc. sequentially superimpose the signature on the electronic file, so the oldest signature is referred to as the first generation signature data, and the next signature is the second generation signature. It is called data, and the nth signature is called nth generation signature data.

  FIG. 3 is a diagram illustrating a data structure of the verification result area in the storage unit of the electronic signature server. The verification result area is an area for storing verification result data that is a result of verifying each signature data of the electronic signature document in association with verification result alteration detection data. In the verification result area, a record is created for each signature data included in the electronic signature document when the electronic signature document is verified. Each record in the verification result area is associated with an electronic signature document code, a signature generation, verification result data, and verification result alteration detection data.

  The signature generation is a code for attaching the first generation, the second generation, the third generation, etc. in order from the oldest in a plurality of signature data in the electronic signature document. The signature generation is determined as the first generation, the second generation, the third generation, etc. in order from the signature time in the plurality of signature data associated with each signature data by the electronic signature document code.

  The verification result data is the result data when each signature data is verified, including the signer name, the signature time, the digital certificate used for the signature, the presence or absence of falsification of the signature, and the expiration of the electronic certificate. Including presence or absence.

  The verification result alteration detection data is data for detecting whether or not each record in the verification result area has been altered in order to ensure the reliability of the verification result data. Specifically, the verification result alteration detection data is a digital signature document code, signature generation, and hash value of the verification result data, which is data other than the verification result alteration detection data.

  In the example shown in FIG. 3, the electronic signature document with the electronic signature document code “00000001” includes signature data from the first generation to the third generation, and verification result data and verification result alteration detection data for each signature generation. Are associated and stored in the storage unit 11. The electronic signature documents with the electronic signature document codes “00000002” and “00000004” have the first generation signature data, and the first generation verification result data and the verification result alteration detection data are associated with each other and stored in the storage unit 11. Has been. Similarly, the electronic signature document with the electronic signature document code “00000003” includes signature data from the first generation to the second generation, and verification result data and verification result alteration detection data are associated with each signature generation. Is stored in the storage unit 11.

  FIG. 4 is a diagram illustrating a data structure of the user information area in the storage unit of the electronic signature server. The user information area is an area for storing the user ID in association with the user's electronic certificate. When there is a signature request, the user information area is referred to when reading the electronic certificate corresponding to the user ID. Each record in the user information area stores a user ID, an electronic certificate, a name, and an affiliation. The electronic certificate may be an electronic certificate itself or a path to a storage location.

  The control unit 12 includes a CPU, a ROM, a RAM, and the like, and performs overall control of the electronic signature server 1 according to a program. For this purpose, the control unit 12 includes an electronic signature unit 111, a verification unit 112, a simple verification unit 113, a verification result alteration detection unit 114, a verification selection unit 115, and a result transmission unit 116.

  Upon receiving a signature request from the user terminal 2, the electronic signature unit 111 reads the user's electronic certificate specified by the user ID included in the signature request from the user information area of the storage unit 11 and signs the signature target. . Here, the signature target is a generic name for data to be signed, and the first generation signature target is an electronic file. The second generation signature object is an electronic file, first generation signature data, and corresponding verification information. The third generation signature target is the second generation signature target, the second generation signature data, and the corresponding verification information. Specifically, the electronic signature unit 111 reads the digital certificate of the signer from the user information area of the storage unit 11 and calculates a digital signature value to be signed based on the electronic certificate. At this time, the electronic signature unit 111 sets the current time acquired from the time measuring unit 13 as the signature time. The electronic signature unit 111 stores the digital signature value, the signature time, and the used electronic certificate in the electronic signature document area of the storage unit 11 as signature data.

  The verification unit 112 verifies that the signature target has not been falsified and that the digital certificate used for the signature is valid using the signature data to be verified. Specifically, in order to determine whether the signature target has been tampered with, the verification unit 112 calculates a hash value by decrypting the digital signature value of the signature target using the digital certificate of the signature data, and the calculated hash A match between the value and the hash value calculated from the signature target stored in the electronic signature document area of the storage unit 11 is confirmed. If these values do not match, the verification unit 112 determines that “falsification has occurred”, and if not, the verification unit 112 determines that “falsification has not occurred”. Further, the verification unit 112 acquires the CRL from the certificate authority 3 in order to determine the validity of the electronic certificate, and confirms whether or not the electronic certificate of the signature data is described in the CRL. When the electronic certificate of the signature data is described in the CRL, the verification unit 112 determines that “there is a problem with validity”. Otherwise, the verification unit 112 determines that “there is no problem with validity”. . The verification unit 112 stores these verification results as verification result data in the verification result area of the storage unit 11 in association with the electronic signature document code and the signature generation. Further, the verification unit 112 stores the CRL used for determining the validity of the digital certificate and the digital certificate of the certificate authority 3 in association with the signature data in the digital signature document area of the storage unit 11 as verification information.

  The simple verification unit 113 performs a process of increasing the verification efficiency by using the verification result data which is the past verification result as the verification result for the signature data to be verified. Specifically, the simple verification unit 113 refers to the verification result area of the storage unit 11 and reads verification result data corresponding to the signature data to be verified. Then, whether or not the verification result data is falsified is confirmed by the verification result falsification detection unit 114 described later. If the verification result data is not falsified, the simple verification unit 113 uses the verification result data as it is as the verification result. On the other hand, when the verification result data is falsified, the simple verification unit 113 notifies a warning to a system administrator and a system log (not shown). Thereafter, similarly to the verification unit 112, the simple verification unit 113 determines whether the signature target has been tampered with. Further, the simple verification unit 113 acquires the CRL from the verification information corresponding to the signature data stored in the digital signature document area of the storage unit 11 in order to determine the validity of the digital certificate, and the signature data It is confirmed whether the electronic certificate is described in the CRL. When the digital certificate of the signature data is described in the CRL, the simple verification unit 113 determines that “there is a problem with validity”. Otherwise, the simple verification unit 113 determines that “there is no problem with validity”. judge. Then, the simple verification unit 113 overwrites and stores the results of these verifications as verification result data in the verification result area of the storage unit 11 in association with the electronic signature document code and the signature generation, and uses them as verification result data.

  The verification result alteration detection unit 114 detects whether or not the verification result data stored in the verification result area of the storage unit 11 has been altered using the verification result alteration detection data. Specifically, the verification result alteration detection unit 114 generates verification result alteration detection data by passing the verification result data through a hash function, and the verification result alteration detection data thus generated and the storage unit 11. The verification result data stored in the verification result area is read and compared with a hash generated, and if they do not match, it is detected that the verification result data has been tampered with.

  When verifying each signature data of the electronic signature document, the verification selection unit 115 selects whether to verify each signature data by either the verification unit 112 or the simple verification unit 113. Specifically, the verification selection unit 115 selects verification by the verification unit when the signature data to be verified is the latest signature data. The verification selection unit 115 also selects verification by the verification unit 112 even when the signature data to be verified is unverified, that is, the verification result data for the signature data does not exist in the verification result area of the storage unit 11. On the other hand, when the verification result data for the verification target signature data exists in the verification result area of the storage unit 11, the verification by the simple verification unit 113 is selected.

  The result transmission means 116 transmits a signature result obtained by processing of the electronic signature server 1 performed in response to a signature request from the user terminal 2 described later, and the electronic signature server 1 performed in response to a verification request from the user terminal 2 described later. The verification result obtained by the above processing is extracted and transmitted through the communication I / F unit 14. The verification result is extracted by reading the verification result data of the same electronic signature document code from the verification result area in the order of signature generation.

  The timer unit 13 provides the control unit 12 with the current time in order to acquire a signature time that is a time when the signature is applied, a verification time that is a time when the verification is performed, and the like. For this purpose, the timer unit 13 is constituted by a clock or the like.

  The communication I / F unit 14 includes a communication interface and a driver that perform communication using a predetermined communication protocol.

  The user terminal 2 performs browsing, a signature request, a verification request, a display of a verification result, and the like for an electronic file and an electronic signature document stored in the storage unit 11. For this purpose, the user terminal 2 is constituted by, for example, a personal computer (PC). The user terminal 2 includes a communication I / F unit 21 that communicates with the electronic signature server 1 through the communication network 4, a control unit 22 that performs various controls of the user terminal 2, and a PIN (Personal Identification Number). It has an input unit 23 for inputting a password and the like, a display unit 24 for displaying a list of electronic files and electronic signature documents, and a storage unit 25 for storing various control information used by the control unit 22.

  The communication I / F unit 21 includes a communication interface and a driver that perform communication using a predetermined communication protocol. The control unit 22 includes at least one of a CPU, a ROM, a RAM, and the like, and performs processing according to a program for overall control of the user terminal 2. The input unit 23 includes a mouse, a keyboard, and the like. The display unit 24 is configured by an LCD or the like. The storage unit 25 includes at least one of a rewritable nonvolatile memory such as a flash memory and an EEPROM, a magnetic hard disk, a rewritable optical disk, and a drive thereof.

  When a verification target is specified by the input unit 23 from the list of electronic files and electronic signature documents displayed on the display unit 24, the control unit 22 converts the electronic signature document code into an electronic signature document code together with the signature request and the verification request. Transmit to the signature server 1. The control unit 22 also transmits the user ID of the user using the user terminal 2 to the electronic signature server 1 when requesting a signature, and the electronic signature unit 111 stores the electronic certificate specified from the user ID. 11 to read the signature.

  The certificate authority 3 is based on a request from the electronic signature server 1 like a P12 (PKCS (Public Key Cryptography Standards) # 12) file composed of an electronic certificate including a public key and user information, a private key, and a PIN. An electronic certificate with a simple password. Here, PKCS is a standard that defines the format of electronic certificates and private keys used in PKI (Public Key Infrastructure). PKCS # 12 is the twelfth standard, and includes private keys and electronic certificates. A format for exchanging documents is defined. Further, the certificate authority 3 manages information on whether each certificate issued by itself is revoked within the validity period. This information is periodically updated, and a list of data in a list format is called a CRL. The certificate authority 3 supplies this CRL to the outside. For this purpose, the certificate authority 3 includes a communication I / F unit 31 that communicates with the electronic signature server 1 through the communication network 4, a control unit 32 that performs various controls of the certificate authority 3, and the CRL and the electronic certificate authority 3. And a storage unit 33 for storing various control information used by the control unit 32 in addition to the certificate.

  The communication I / F unit 31 includes a communication interface and a driver that perform communication using a predetermined communication protocol. The control unit 32 includes a CPU, a ROM, a RAM, and the like, and performs the overall control of the certificate authority 3 according to a program. The storage unit 33 includes at least one of a rewritable nonvolatile memory such as a flash memory and an EEPROM, a magnetic hard disk, a rewritable optical disk, and a drive thereof.

  The communication network 4 is connected to the electronic signature server 1, the user terminal 2, and the certificate authority 3. For this purpose, the communication network 4 is configured by a communication line that enables data transmission / reception between remote places such as a dedicated line, the Internet, a mobile phone line, and a general public line, or between indoor remote places.

  Next, the processing flow of the electronic signature server in FIG. 1 will be described. Note that the processing flow described below is controlled by a program executed by the control unit 12.

  FIG. 5 is a flowchart of processing of the electronic signature server of FIG. 1 performed in response to a signature request. The processing flow shown in FIG. 5 is executed every time the electronic signature server 1 receives a signature request designating an electronic signature document from the user terminal 2. First, the electronic signature unit 111 determines whether the signer's electronic certificate corresponding to the user ID included in the signature request exists in the user information area of the storage unit 11 (step S1). If there is no electronic certificate, the result transmission unit 116 transmits the signature result to the user terminal 2 (step S2), and the processing flow is terminated.

  On the other hand, when there is an electronic certificate, the electronic signature unit 111 determines whether or not there is a signature in the past in the electronic signature document area of the storage unit 11 (step S3). If there is no signature in the past, the digital signature unit 111 generates signature data for the signature target in the digital signature document using the digital certificate of the signer and adds it to the digital signature document (step S4), and step S2 Proceed to

  On the other hand, if there is a signature in the past, the verification selecting unit 115 extracts all signature data of the electronic signature document (step S5), and sets signature data to be verified from all the signature data (step S6). . Next, the verification selection unit 115 determines whether verification information exists in the electronic signature document area of the storage unit 11 (step S7). When there is no verification information, the verification selection unit 115 selects verification by the verification unit 112, and the verification unit 112 verifies the validity of the electronic certificate included in the signature data and the presence / absence of falsification of the electronic signature document. Result data is generated (step S8). Next, the verification unit 112 stores the verification result data in the verification result area of the storage unit 11 (step S9), and stores the verification information in the electronic signature document area of the storage unit 11 (step S10). Next, the verification selecting unit 115 determines whether or not verification of all signature data of the electronic signature document has been completed (step S11). If the verification of all the signature data of the electronic signature document is completed, the process proceeds to step S4, and if not, the process returns to step S6.

  On the other hand, if there is verification information, the verification selection unit 115 selects the verification by the simple verification unit 113, and the verification result alteration detection unit 114 performs the alteration detection process of the verification result data (step S12). It is determined whether or not tampering has occurred (step S13). If there is no tampering, the process proceeds to step S11.

  On the other hand, if tampering occurs, the simple verification unit 113 notifies a warning to a system administrator or system log (not shown) (step S14), and acquires verification information from the electronic signature document area of the storage unit 11 (step S15). . Next, the simple verification unit 113 verifies the validity of the digital certificate included in the signature data and the presence / absence of falsification of the digital signature document, and generates verification result data (step S16). The verification result data stored in the verification result area of the storage unit 11 is updated (step S17), and the process proceeds to step S11.

  According to the processing flow shown in FIG. 5, if the electronic signature unit 111 determines in step S3 that there is no signature data in the electronic signature document, the electronic signature means 111 uses the digital certificate of the signer in step S2 to sign the electronic file. Data is generated and added to the electronic signature document. If the electronic signature unit 111 determines in step S3 that the electronic signature document already has signature data, and the verification selection unit 115 determines in step S7 that there is no verification information corresponding to the signature data, the verification unit 112, the verification result data is stored in the verification result area of the storage unit 11, the verification information is added to the digital signature document, and then the signature data for the signature target is generated using the digital certificate of the signer. Add to the electronic signature document. Further, when the electronic signature unit 111 determines in step S3 that the digital signature document already has signature data, and in step S7, the verification selection unit 115 determines that there is verification information corresponding to the signature data, simple verification is performed. The verification is performed by the means 113 and the verification result data is reused. Thus, by making it possible to select the simple verification by the simple verification means 113, the electronic signature verification can be performed at a higher speed. Further, by generating verification result data in advance at the time of signature, the number of signature data that enables selection of simple verification by the simple verification unit 113, that is, the number of signature generations can be increased.

  FIG. 6 is a flowchart of processing of the electronic signature server of FIG. 1 performed in response to the verification request. The processing flow shown in FIG. 6 is executed each time the electronic signature server 1 receives a verification request specifying the electronic signature document from the user terminal 2. First, the verification selection unit 115 reads an electronic signature document designated by the user terminal 2 (step S21). Next, the verification selecting unit 115 determines whether or not the electronic signature document designated by the user terminal 2 is stored in the electronic signature document area of the storage unit 11 (step S22). If there is no designated electronic signature document, the result transmitting unit 116 transmits the verification result to the user terminal 2 (step S23), and the processing flow is ended.

  On the other hand, if there is a designated electronic signature document, the verification selection means 115 performs the processes of steps S5 and S6. After the signature data is set in step S6, the verification selecting unit 115 determines whether the signature data to be verified is the latest in the same electronic signature document or there is no corresponding verification information, that is, verification result data. (Step S24). When the signature data to be verified is the latest in the same electronic signature document or there is no corresponding verification information, the verification selection unit 115 selects to perform verification by the verification unit 112, and steps S8, S9, and S11 are performed. Perform the process. Otherwise, the verification selection unit 115 selects to perform verification by the simple verification unit 113, and performs the processes of steps S12 to S17 and step S11. If it is determined in step S11 that the verification of all the signature data of the electronic signature document has been completed, the result transmission unit 116 extracts the verification result (step S25), and proceeds to step S23.

  According to the processing flow shown in FIG. 6, the verification selection unit 115 determines in step S24 that the signature data to be verified is the latest in the same electronic signature document or that there is no corresponding verification information. In this case, verification by the verification unit 112 is selected, and verification by the simple verification unit 113 can be selected for other signature data. Therefore, when the latest signature is always verified, and other signatures are also verified at least once and the reliability of verification of the electronic signature is ensured, the verification result data is extracted as the verification result as it is. Signature verification can be performed at high speed. If the simple verification unit 113 determines in step S13 that the past verification result data is falsified, the verification information is used to verify the validity of the digital certificate included in the corresponding signature data and the falsification of the digital signature document. The verification result data is generated again and updated.

  Therefore, when the reliability of verification of the electronic signature is ensured, the verification of the electronic signature can be performed at high speed by extracting the verification result data as the verification result as it is. Further, when it is necessary to ensure the reliability of verification of the electronic signature, the verification of the electronic signature can be performed with high reliability by updating the verification result data.

  The present invention is not limited to the above-described embodiment, and many changes and modifications can be made. For example, the case where the electronic signature system having the electronic signature verification apparatus according to the present invention is applied to the in-house system has been described. However, the electronic signature system having the electronic signature verification apparatus according to the present invention is applied to a system other than the internal system. can do.

  The case where the electronic signature server 1 receives the electronic file from the outside as the storage target and adds the electronic signature document code when the electronic file is stored for the first time has been described. However, the electronic signature server 1 can store only the electronic file as the storage target. Alternatively, electronic signature documents can be received from the outside, and an electronic signature document code can be attached when these documents are first stored.

  Although the case where the verification result alteration detection unit 114 detects the alteration of the verification result data has been described, the verification result alteration detection unit can be used to guarantee that the verification result data is not falsified by another method. Detection of alteration of verification result data by 114 can be omitted.

  The case where the verification by the simple verification unit 113 is selected when the verification result data for the verification target signature data exists has been described. However, even when the verification result data for the verification target signature data exists, the importance of the signature, Based on the signature generation or the like, verification by the verification unit 112 can be selected instead of the simple verification unit 113 according to the level of reliability and the processing time. For example, the verification selection unit 115 determines whether or not the data is a specific signer (for example, an authorized person) or a specific signature generation (for example, the first generation) designated at the time of the verification request. Judgment is made by referring to the signer name, the signature generation of the verification result data, etc., and verification by the verification unit 112 is selected instead of the simple verification unit 113. In addition, when the reliability needs to be increased, the verification by the verification unit 112 can be selected, and when the processing time needs to be shortened, the verification by the simple verification unit 113 can be selected.

  The case where the CRL is used as the revocation information has been described. As the revocation information, the result obtained by using the method OCSP (Online Certificate Status Protocol) for inquiring whether or not the certificate in the certificate authority 3 is revoked , Instead of CRL or in combination with CRL.

  In the processing flowcharts of FIGS. 5 and 6, all signatures regardless of whether or not the content of the verification result data by the verification unit 112 or the simple verification unit 113 is “NG” or “No problem in validity”. Although the case where data is verified has been described, the processing can be stopped when the content of the verification result data is NG.

  In the flowchart of FIG. 5, the case where the signature is applied regardless of whether or not the content of the verification result data by the verification unit 112 is NG is described. However, when the content of the verification result data is NG, the processing is stopped. It can also be done.

  Although the case where the electronic signature document area, the verification result area, and the user information area are stored in the storage unit 11 has been described, a file storage apparatus that stores the electronic signature document, a verification result storage apparatus that stores verification result data, and user information Can be provided separately from the electronic signature server 1. In this case, the electronic signature server 1 transmits the electronic signature document stored in the file storage device, the verification result data stored in the verification result storage device, and the user information stored in the user information management database to the communication network 4. To be able to read through.

  Although the method for signing the electronic signature document together with the CRL of the certificate at the time of signing has been described, it may be repeated that only the signature is applied to the electronic signature document. In this case, since an electronic signature document having a plurality of signature data having no corresponding verification information is generated, the verification information can be collectively stored and signed at a certain timing.

  The case where only the electronic signature is applied to the electronic signature document has been described. However, a time stamp authority (see FIG. 5) connected to the communication network 4 instead of applying the electronic signature to the electronic signature document or instead of applying the electronic signature to the electronic signature document. The electronic signature document can also be time stamped.

  Although the case where verification result data is generated by passing the verification result data through a hash function has been described, verification result data can also be generated by passing the verification result data through a function other than the hash function .

  The first generation is an electronic file, the second generation is signature data of the first generation and corresponding verification information, and the third generation is signature data of the second generation and corresponding verification information. Various selection methods may be applied, such as the fourth generation being the third generation signature data and corresponding verification information, and so on.

DESCRIPTION OF SYMBOLS 1 Electronic signature server 2 User terminal 3 Certification authority 4 Communication network 11, 25, 33 Storage part 12, 22, 32 Control part 13 Timekeeping part 14, 21, 31 Communication I / F part 23 Input part 24 Display part 111 Electronic signature means 112 Verification Unit 113 Simple Verification Unit 114 Verification Result Tampering Detection Unit 115 Verification Selection Unit 116 Result Transmission Unit

Claims (3)

A storage unit for storing an electronic signature document to which an electronic signature is applied and verification result data thereof;
Upon receipt of a verification request, an electronic signature verification apparatus having a control unit that verifies all signature data applied to the electronic signature document, generates verification result data, and generates and outputs a verification result from the verification result data Because
The electronic signature document includes at least verification information including an electronic file, signature data including a signature time generated each time a signature is applied, and information capable of determining validity of the electronic certificate used for the signature. Configured,
The controller is
Verification means for verifying the validity of the electronic certificate included in each of the signature data and the presence or absence of falsification of the electronic signature document, and generating verification result data;
Simple verification means for verifying using past verification result data stored in the storage unit;
If the signature data to be verified is the latest in the same electronic signature document or the corresponding verification information does not exist, select the verification by the verification means, and select the verification by the simple verification means for the other signature data A validation selection means to enable;
An electronic signature verification apparatus comprising:   When the past verification result data has been tampered with, the simple verification means uses the verification information to verify the validity of the electronic certificate included in the corresponding signature data and whether or not the electronic signature document has been tampered with. The electronic signature verification apparatus according to claim 1, wherein verification result data is generated. The controller is
When a signature request specifying an electronic signature document is received,
If there is no signature data in the electronic signature document, the signature data for the electronic file is generated using the electronic certificate of the signer and added to the electronic signature document,
If the digital signature document already has signature data and there is no verification information corresponding to the signature data, the verification unit verifies the verification result data and stores the verification result data in the storage unit, and verifies the digital signature document. After adding the information, using the digital certificate of the signer to generate signature data for a predetermined signature object, add it to the electronic signature document,
The electronic signature unit further includes an electronic signature unit that verifies by the simple verification unit and updates verification result data if the digital signature document already has signature data and has verification information corresponding to the signature data. 2. The electronic signature verification apparatus according to 2.

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