JP6916635B2 - Timestamp management device, electronic file viewing device and program - Google Patents

Description

The present invention relates to a time stamp management device, an electronic file viewing device, and a program capable of managing a time stamp token of an electronic file.

For example, by adding a time stamp to electronic data such as documents, images, figures, and sounds, the electronic data exists at the date and time indicated by the time stamp, and the electronic data becomes available after the date and time indicated by the time stamp. Time-stamping technology that facilitates proof that it has not been tampered with is widespread.

To explain this technology concretely by taking the case where the electronic data is document data as an example, the user generates a hash value of the document data contained in the document file and sends this hash value to the time authentication authority. Send and request the time certification body to issue a time stamp. In response to this, the time certification body generates a time stamp token by digitally signing the received hash value, time information indicating the time stamp issuance time, and the like with a private key. Normally, the digital certificate of the time certification body is also included in the time stamp token. This digital certificate contains a public key used to verify the signature of the time certification authority on the time stamp token. Then, the time certification body sends a response including the time stamp token to the user who requested the issuance of the time stamp.

The user receives the time stamp token from the time authentication authority and adds the received time stamp token to the document file. For example, when the document file is a PDF file, the user can embed the time stamp token in the PDF file. As a result, the user can manage the document data and the time stamp token in a single document file.

The following Patent Document 1 describes a time authentication technique using a time stamp. However, Patent Document 1 does not describe a technique for managing a time stamp token integrated with an electronic file by adding the time stamp token to the electronic file.

Japanese Unexamined Patent Publication No. 2016-170643

Currently, a time stamp storage service has been proposed in which a specific institution keeps time stamp tokens from users and stores them. Hereinafter, a specific institution that provides a time stamp storage service is referred to as a "time stamp storage institution". According to the time stamp storage service, the user can deposit the time stamp token in the time stamp storage institution and can safely store it for a long period of time.

By the way, when the user manages the time stamp token integrated with the electronic file by adding the time stamp token to the electronic file, in order to store the time stamp token in the time stamp storage organization, the user Needs to retrieve the timestamp token from the electronic file. Strictly speaking, the user needs to generate a copy of the time stamp token attached to the electronic file and make the copy of the time stamp token independent of the electronic file.

However, it is not easy for a general user to take out the time stamp token from the electronic file. In order to enable the user to easily retrieve the time stamp token from the electronic file, a new means for extracting the time stamp token from the electronic file according to the user's instruction input is required. ..

Further, Patent Document 1 does not describe a technique for extracting a time stamp token from an electronic file.

The present invention has been made in view of the above-mentioned problems, for example, and an object of the present invention is that a user who manages a time stamp token by adding it to an electronic file can easily use the time stamp storage service. It is to provide a time stamp management device, an electronic file viewing device and a program that enable the above.

In order to solve the above problems, the first time stamp management device of the present invention includes main data, a hash value of the main data, time information given by the time certification body, and an electronic certificate of the time certification body. The electronic file designation unit that has the included time stamp token and specifies the electronic file stored in the first storage location, and the hash value of the main data of the electronic file are calculated and calculated. It is included in the hash value comparison unit that compares the hash value with the hash value of the main data included in the time stamp token of the electronic file, and the electronic file designated by the electronic file designation unit. A time stamp token file containing the time stamp token duplication unit that duplicates the time stamp token, the storage location specification unit that specifies the second storage location, and the time stamp token duplicated by the time stamp token duplication unit. A time stamp token file output unit that generates the data and stores the generated time stamp token file in the second storage location designated by the storage location designation unit, and the result of comparison by the hash value comparison unit, When the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file match each other, a time stamp token file output button is displayed on the screen of the display device. Then, when the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit generates the time stamp token file, and the generated time stamp token file is generated. Is stored in the second storage location designated by the storage location designation unit, and is included in the calculated hash value and the time stamp token of the electronic file as a result of comparison by the hash value comparison unit. If the hash values of the main data do not match each other, the fact that the electronic file is not normal is displayed on the screen of the display device, and the time stamp token file output button is not displayed on the screen of the display device. It is characterized in that it cannot be displayed or pressed.

According to the first time stamp management device of the present invention, the user can easily obtain a time stamp token file containing a copy of the time stamp token attached to the electronic file that has not been tampered with. .. As a result, when using the time stamp storage service, the user only needs to store the time stamp token file in the time stamp storage organization, so that the time stamp storage service can be easily used.

In order to solve the above problems, the second time stamp management device of the present invention includes the main data, the hash value of the main data, the time information given by the time certification body, and the electronic certificate of the time certification body. An electronic file designation unit having a time stamp token included and designating an electronic file stored in the first storage location, and the electronic certificate included in the time stamp token of the electronic file. A certificate validity judgment unit for determining whether or not the validity is recognized, a time stamp token duplication unit for duplicating the time stamp token included in the electronic file specified by the electronic file designation unit, and the first A time stamp token file including the time stamp token duplicated by the time stamp token duplication unit and the storage place designation unit that specifies the storage location of 2 is generated, and the generated time stamp token file is stored in the storage location. It includes a time stamp token file output unit that stores in the second storage location designated by the designated unit, and is included in the time stamp token of the electronic file as a result of determination by the certificate validity determination unit. If the validity of the electronic certificate is confirmed, the time stamp token file output button is displayed on the screen of the display device, and the time stamp token file output button displayed on the screen of the display device is pressed. At that time, the time stamp token file output unit generates the time stamp token file, and the generated time stamp token file is stored in the second storage location designated by the storage location designation unit. As a result of the judgment by the certificate validity determination unit, if the validity of the electronic certificate included in the time stamp token of the electronic file is not confirmed, the indication that the electronic file is not normal is displayed. It is characterized in that it is displayed on the screen of the device and the time stamp token file output button cannot be displayed or pressed on the screen of the display device.

According to the second time stamp management device of the present invention, the user can use a time stamp token file containing a copy of the time stamp token attached to the electronic file to which the valid electronic certificate is attached. Can be easily obtained. As a result, when using the time stamp storage service, the user only needs to store the time stamp token file in the time stamp storage organization, so that the time stamp storage service can be easily used.

Further, in the first time stamp management device of the present invention described above, the time stamp token included in the electronic file is compared with the time stamp token file, and the result of the comparison is output. When the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file match each other as a result of comparison by the hash value comparison unit. , The time stamp token file output button and the time stamp token comparison button are displayed on the screen of the display device, and when the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file The output unit generates the time stamp token file, stores the generated time stamp token file in the second storage location designated by the storage location designation unit, and displays the time stamp token file on the screen of the display device. When the time stamp token comparison button is pressed, the time stamp token file comparison unit compares the time stamp token included in the electronic file with the time stamp token file, outputs the result of the comparison, and outputs the result of the comparison. As a result of comparison by the hash value comparison unit, if the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file do not match each other, the electronic file is released. The fact that it is not normal may be displayed on the screen of the display device, and the time stamp token file output button and the time stamp token comparison button may be hidden or cannot be pressed on the screen of the display device.

Further, in the second time stamp management device of the present invention described above, the time stamp token included in the electronic file is compared with the time stamp token file, and the result of the comparison is output. If the validity of the electronic certificate included in the time stamp token of the electronic file is confirmed as a result of the judgment by the certificate validity determination unit, the screen of the display device is provided. When the time stamp token file output button and the time stamp token comparison button are displayed and the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit causes the time. A stamp token file is generated, the generated time stamp token file is stored in the second storage location designated by the storage location designation unit, and the time stamp token comparison button displayed on the screen of the display device is displayed. When pressed, the time stamp token file comparison unit compares the time stamp token contained in the electronic file with the time stamp token file, outputs the result of the comparison, and determines the validity of the certificate. As a result of the judgment by the department, if the validity of the electronic certificate included in the time stamp token of the electronic file is not recognized, the fact that the electronic file is not normal is displayed on the screen of the display device. However, the time stamp token file output button and the time stamp token comparison button may be hidden or cannot be pressed on the screen of the display device.

Further, in the second time stamp management device of the present invention described above, in the certificate validity determination unit, (a) the electronic certificate included in the time stamp token of the electronic file has an expiration date. Being inside, (b) the signature of the electronic certificate included in the time stamp token of the electronic file is normal, and (c) being included in the time stamp token of the electronic file. The electronic contained in the time stamp token of the electronic file when the electronic certificate satisfies any one of the following that the electronic certificate has not been revoked for a reason other than the expiration date. The electronic file has the first determination method for determining the validity of the certificate and the electronic file when any two of the above conditions (a), (b) and (c) are satisfied. The second determination method for determining that the validity of the electronic certificate included in the time stamp token is recognized, and the electronic file when all of the above conditions (a), (b) and (c) are satisfied. Among the third determination methods for determining that the validity of the electronic certificate included in the time stamp token possessed by the user is recognized, the electronic file has the electronic file by any of the determination methods specified by the user. The validity of the electronic certificate included in the time stamp token may be determined.

In order to solve the above problems, the first electronic file viewing device of the present invention includes the main data, the hash value of the main data, the time information given by the time certification body, and the electronic certificate of the time certification body. An electronic file designation unit that has a time stamp token included and specifies an electronic file stored in the first storage location, and the contents of the main data of the electronic file designated by the electronic file designation unit. The display control unit to be displayed on the screen of the display device and the hash value of the main data held by the electronic file are calculated, and the calculated hash value and the time stamp token included in the electronic file are included. A hash value comparison unit that compares the hash value of the main data, a time stamp token duplication unit that duplicates the time stamp token included in the electronic file specified by the electronic file designation unit, and a second storage location. A time stamp token file containing the time stamp token duplicated by the time stamp token duplication unit and the storage location specification unit that specifies the data is generated, and the generated time stamp token file is specified by the storage location specification unit. A time stamp token file output unit to be stored in the second storage location is provided, and as a result of comparison by the hash value comparison unit, the calculated hash value and the time stamp token included in the electronic file are included. When the hash values of the main data match each other, the time stamp token file output button is displayed on the screen of the display device, and the time stamp token file output button displayed on the screen of the display device is displayed. When is pressed, the time stamp token file output unit generates the time stamp token file, and the generated time stamp token file is stored in the second storage location designated by the storage location designation unit. Then, as a result of comparison by the hash value comparison unit, if the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file do not match each other, the said It is characterized in that the fact that the electronic file is not normal is displayed on the screen of the display device, and the time stamp token file output button cannot be displayed or pressed on the screen of the display device.

According to the first electronic file viewing device of the present invention, the user can centrally view the electronic file and acquire the time stamp token file corresponding to the electronic file that has not been tampered with.

In order to solve the above problems, the second electronic file viewing device of the present invention includes the main data, the hash value of the main data, the time information given by the time certification body, and the electronic certificate of the time certification body. An electronic file designation unit that has a time stamp token included and specifies an electronic file stored in the first storage location, and the contents of the main data of the electronic file designated by the electronic file designation unit. A display control unit to be displayed on the screen of the display device, a certificate validity determination unit for determining whether or not the validity of the electronic certificate included in the time stamp token of the electronic file is recognized, and a certificate validity determination unit. A time stamp token duplication unit that duplicates the time stamp token included in the electronic file designated by the electronic file designation unit, a storage location designation unit that specifies a second storage location, and the time stamp token duplication unit. A time stamp token file containing the time stamp token duplicated by is generated, and the generated time stamp token file is stored in the second storage location designated by the storage location designation unit. The display device is provided with an output unit, and when the validity of the electronic certificate included in the time stamp token of the electronic file is confirmed as a result of determination by the certificate validity determination unit. When the time stamp token file output button is displayed on the screen of, and the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit causes the time stamp token file. Is generated, the generated time stamp token file is stored in the second storage location designated by the storage location designation unit, and as a result of determination by the certificate validity determination unit, the time held by the electronic file. If the validity of the electronic certificate included in the stamp token is not recognized, the fact that the electronic file is not normal is displayed on the screen of the display device, and the time stamp token is displayed on the screen of the display device. The feature is that the file output button is hidden or cannot be pressed.

According to the second electronic file viewing device of the present invention, the user unifies the viewing of the electronic file and the acquisition of the time stamp token file corresponding to the electronic file to which the valid electronic certificate is attached. Can be done

In order to solve the above problems, the program of the present invention causes a computer to function as the first or second time stamp management device of the present invention, or the computer as the first or second electronic file viewing device of the present invention. To work.

According to the present invention, a user who manages by adding a time stamp token to an electronic file can easily use the time stamp storage service.

It is explanatory drawing which shows the time authentication system which includes the user terminal which is embodiment of the time stamp management apparatus and the electronic file browsing apparatus of this invention. It is explanatory drawing which shows the structure of a document file. It is explanatory drawing which shows the structure of the time stamp token file. It is a flowchart which shows the document file browsing process in the user terminal in FIG. It is explanatory drawing which shows the document browsing screen in the user terminal in FIG. It is a flowchart which shows the content of the verification process in FIG. It is explanatory drawing which shows the verification result window (when the document file is normal) in the user terminal in FIG. It is explanatory drawing which shows the verification result window (when the document file is not normal) in the user terminal in FIG. It is explanatory drawing which shows the process selection window in the user terminal in FIG. It is explanatory drawing which shows the window which shows the comparison result of the time stamp in the user terminal in FIG.

(Time authentication system)
FIG. 1 shows a time authentication system 1. In FIG. 1, the time authentication system 1 includes a time stamp issuing server 2, a time distribution server 3, an electronic authentication management server 4, a time stamp storage server 5, and a user terminal 6. These are connected to each other so as to be able to communicate with each other via a computer network 7 such as the Internet.

The time stamp issuing server 2 is provided in the time certification body (TSA) and issues the time stamp. That is, when the user transmits the hash value 35 of the document data 32 included in the document file 31 (see FIG. 2) from the user terminal 6 to the time stamp issuing server 2 and requests the issuance of the time stamp, the time The stamp issuing server 2 generates the time stamp token information 34 by digitally signing the hash value 35 transmitted from the user terminal 6 and the time information 36 indicating the time stamp issuing time with a private key. Further, the time stamp issuing server 2 adds the digital certificate 37 of the time authentication organization to the time stamp token information 34. Then, the time stamp issuing server 2 transmits the time stamp token 33 including the time stamp token information 34 and the digital certificate 37 to the user terminal 6 of the user who requested the issuance of the time stamp. The user adds the time stamp token 33 transmitted from the time stamp issuing server 2 to the document file 31.

The time distribution server 3 is provided in the time distribution organization (TAA), distributes the time to the time authentication organization, and audits the clock of the time authentication organization. The time information 36 used to generate the time stamp token information 34 in the time stamp issuing server 2 of the time authentication organization is generated using the time indicated by the clock of the time authentication organization audited by the time distribution organization.

The electronic authentication management server 4 is provided in an electronic authentication organization (CA) and issues and revokes an electronic certificate.

The time stamp storage server 5 is provided in the time stamp storage organization and stores the time stamp. That is, when the user transmits the time stamp token file 41 (see FIG. 3) from the user terminal 6 to the time stamp storage server 5 and requests the storage of the time stamp token file 41, the time stamp storage server 5 is used. The time stamp token file 41 transmitted from the personal terminal 6 is stored. Further, when the user requests the transmission of the time stamp token file 41, the time stamp storage server 5 uses the stored time stamp token file 41 as the user of the user who requested the transmission of the time stamp token file 41. Send to terminal 6.

(User terminal)
The user terminal 6 is a terminal used by the user. The user terminal 6 is an embodiment of the time stamp management device and the electronic file browsing device of the present invention. The user terminal 6 is, for example, a personal computer, and includes an arithmetic processing unit 11, a temporary storage unit 12, an operation unit 13, a display unit 14, a communication unit 15, and an external storage unit 16. The arithmetic processing unit 11 is, for example, a CPU (Central Processing Unit). The temporary storage unit 12 is a storage device that can be directly accessed by the arithmetic processing unit 11 and is used for reading and writing data and the like required for processing performed by the arithmetic processing unit 11, and is, for example, a main storage device. The operation unit 13 is, for example, a keyboard, a pointing device, or the like. The display unit 14 is a display device such as a display. The communication unit 15 is a communication control circuit for communicating with another device via the computer network 7. The external storage unit 16 is a storage device used for long-term storage of data and the like, and is, for example, a hard disk. Although not shown, the user terminal 6 is provided with a port for connecting a portable external storage device such as a USB (universal serial bus) memory, an optical disk drive device, and the like.

Further, the arithmetic processing unit 11 includes a document file designation unit 21, a display control unit 22, a verification unit 23, a determination method setting unit 24, a time stamp token output processing unit 25, and a time stamp token comparison processing unit 26. These are realized by executing a program for operating the computer as a time stamp management device and an electronic file browsing device.

The document file designation unit 21 has a function of designating the document file 31 stored in the external storage unit 16. The display control unit 22 has a function of displaying the contents of the document data 32 included in the document file 31 designated by the document file designation unit 21 on the screen of the display unit 14. The verification unit 23 has a function of verifying whether or not the document file 31 has been tampered with after the time indicated by the time stamp token 33. Further, the verification unit 23 has a function of determining whether or not the validity of the digital certificate 37 included in the time stamp token 33 attached to the document file 31 is recognized. Here, if the validity of the digital certificate 37 is recognized, the signature 40 of the time authentication authority included in the time stamp token 33 attached to the document file 31 is normal, and the signature 40 is verified. It means that the digital certificate 37 for the purpose is valid. The determination method setting unit 24 has a function of setting a method for determining the validity of the digital certificate 37 performed by the verification unit 23. The time stamp token output processing unit 25 duplicates the time stamp token 33 added to the document file 31 designated by the document file specification unit 21, and the time stamp token file including the duplicated time stamp token 33. It has a function of generating 41 and storing the generated time stamp token file 41 in the external storage unit 16. The time stamp token comparison processing unit 26 has a function of comparing the time stamp token file 41 stored in the external storage unit 16 or the like with the time stamp token 33 added to the document file 31 and outputting the result of the comparison. Have.

(Document file)
FIG. 2 shows the structure of the document file 31. In FIG. 2, the document file 31 is an electronic file of a document, and the document file 31 includes document data 32, which is document data, as main data. Further, a time stamp token 33 is added to the document file 31. The time stamp token 33 is transmitted from the time stamp issuing server 2 of the time authentication organization and added to the document file 31 by the user. The time stamp token 33 includes the time stamp token information 34 generated by the time certification body and the digital certificate 37 of the time certification body. The time stamp token information 34 includes a hash value 35 of the document data 32 and time information 36 indicating the time stamp issuance time generated by the time authentication authority. The digital certificate 37 is a public key certificate. The digital certificate 37 includes a public key 38 used for decrypting (verifying) the time stamp token information 34, an expiration date information 39 indicating the expiration date of the digital certificate 37, and an electronic authentication organization that issued the digital certificate 37. Signature 40 is included. The document file 31 is, for example, a PDF file.

(Timestamp token file)
FIG. 3 shows the structure of the time stamp token file 41. The time stamp token file 41 is a file including a copy of the time stamp token 33 added to the document file 31. As shown in FIG. 3, the content of the time stamp token file 41 is the same as the content of the time stamp token 33. Further, the time stamp token file 41 does not include the document data 32.

(Document file viewing process)
FIG. 4 shows a document file browsing process performed on the user terminal 6. The following functions are realized by the document file viewing process.
(1) Display of the contents of the document data: The contents of the document data 32 in the document file 31 can be displayed on the screen. It is a function as a so-called document viewer.
(2) Verification of the document file: The time stamp token information 34 included in the time stamp token 33 added to the document file 31 is used to determine whether or not the document file 31 has been tampered with, and the document file 31 is added to the document file 31. The validity of the electronic certificate 37 included in the time stamp token 33 can be determined, and the determination results can be displayed on the screen.
(3) Output of time stamp token file: The time stamp token 33 added to the document file 31 is duplicated, and the user specifies the time stamp token file 41 including the duplication of the time stamp token 33 in the external storage unit 16. Can be memorized in place.
(4) Comparison of time stamp tokens: The time stamp token 33 added to the document file 31 can be compared with the time stamp token file 41 specified by the user, and the result can be displayed on the screen.

The contents of the document file viewing process are as follows. In FIG. 4, first, the user operates the operation unit 13, specifies the document file 31 stored in a certain storage location (first storage location) in the external storage unit 16, and opens the document file 31. A command to that effect is input to the user terminal 6. According to the designated input by the user, the document file designation unit 21 designates the document file 31 stored in the external storage unit 16 and reads the designated document file 31 into the temporary storage unit 12 (step S1).

Subsequently, the display control unit 22 displays the contents of the document data 32 in the document file 31 designated by the document file designation unit 21 on the screen of the display unit 14 (step S2). Here, FIG. 5 shows a document viewing screen 51 displaying the contents of the document data 32. In the process of step S2, the document viewing screen 51 as shown in FIG. 5 is formed on the screen of the display unit 14.

Subsequently, the verification unit 23 executes a verification process on the document file 31 designated by the document file designation unit 21 (step S3). Here, FIG. 6 shows the content of this verification process. In FIG. 6, the verification unit 23 first determines whether or not the document file 31 has been tampered with (step S21). The verification unit 23 makes this determination, for example, as follows. That is, the verification unit 23 calculates the hash value of the document data 32 in the document file 31. A hash function is used to calculate the hash value. The hash function is stored in the external storage unit 16 or the like. Further, the verification unit 23 decrypts the time stamp token information 34 included in the time stamp token 33 added to the document file 31. To decrypt the time stamp token information 34, the public key 38 in the digital certificate 37 included in the time stamp token 33 attached to the document file 31 is used. Subsequently, the verification unit 23 compares the calculated hash value (current hash value) with the hash value 35 (hash value at the time of issuing the time stamp) included in the decrypted time stamp token information 34. When the document file 31 has not been tampered with (that is, when neither the document data 32 nor the time stamp token information 34 has been tampered with), it is included in the calculated hash value and the decrypted time stamp token information 34. The hash value 35 and the hash value 35 match each other. On the other hand, when the document file 31 has been tampered with (that is, when the document data 32 or the time stamp token information 34 has been tampered with), it is included in the calculated hash value and the decrypted time stamp token information 34. The hash value 35 does not match each other. The verification unit 23 stores the comparison result in the temporary storage unit 12.

Subsequently, the verification unit 23 determines whether or not the expiration date of the digital certificate 37 has been exceeded (step S22). The verification unit 23 makes this determination, for example, as follows. That is, the verification unit 23 reads the expiration date indicated by the expiration date information 39 in the digital certificate 37 included in the time stamp token 33 attached to the document file 31, and the current date and time sets the read expiration date. Determine if it is not exceeded. Then, the verification unit 23 stores this determination result in the temporary storage unit 12.

Subsequently, the verification unit 23 verifies the signature 40 of the digital certificate 37 (step S23). That is, the verification unit 23 reads the signature 40 of the electronic authentication authority included in the digital certificate 37 and determines whether or not this is normal. Then, the verification unit 23 stores this determination result in the temporary storage unit 12.

Subsequently, the verification unit 23 determines whether or not the digital certificate 37 has been revoked for a reason other than the expiration of the expiration date (step S24). The verification unit 23 makes this determination, for example, as follows. That is, the verification unit 23 controls the communication unit 15 to access the electronic authentication management server 4 of the electronic authentication organization, and the revocation information of the electronic certificate 37 included in the time stamp token 33 attached to the document file 31. Check for the existence of. Then, the verification unit 23 determines that the digital certificate 37 has not been revoked for a reason other than the expiration of the expiration date when the revocation information does not exist, and when the revocation information exists, the digital certificate It is determined that 37 has expired for reasons other than the expiration of the expiration date. Then, the verification unit 23 stores this determination result in the temporary storage unit 12. This completes the verification process for the document file 31 designated by the document file designation unit 21.

After the process of step S2 in FIG. 4 is executed, the content of the document data 32 in the document file 31 designated by the document file designation unit 21 is displayed on the document viewing screen 51. The user can confirm the contents of the document data 32 by looking at the document viewing screen 51. Further, after the verification process is completed, the arithmetic processing unit 11 forms the verification result display button 52 in the document viewing screen 51 as shown in FIG. The user can confirm the result of the verification process by operating the operation unit 13 and pressing the verification result display button 52.

That is, the arithmetic processing unit 11 determines whether or not the verification result display button 52 is pressed, and if the verification result display button 52 is pressed (step S4: YES), the arithmetic processing unit 11 displays the result of the verification process. It is displayed on 14 screens. For example, the arithmetic processing unit 11 performs the following processing. That is, after the above verification process is completed, the temporary storage unit 12 receives (1) the hash value calculated in step S21 in FIG. 6 and the hash value 35 included in the decrypted time stamp token information 34. As a result of comparison, (2) a judgment result as to whether or not the expiration date of the digital certificate 37 has been exceeded, (3) a judgment result as to whether or not the signature 40 of the digital certificate 37 is normal, and (4) an electronic certificate. The judgment result of whether or not the document 37 has not expired for a reason other than the expiration of the expiration date is stored. From these comparison results and determination results, the arithmetic processing unit 11 has found that the hash value calculated in step S21 in FIG. 6 and the hash value 35 included in the decoded time stamp token information 34 match each other. The expiration date of the digital certificate 37 has not expired, the signature 40 of the digital certificate 37 is normal, and the digital certificate 37 has not been revoked for any reason other than the expiration date, that is, the document file. When it is recognized that 31 is normal, the fact that the document file 31 is normal is displayed on the screen of the display unit 14 (step S5: YES, step S6).

Here, FIG. 7 shows a verification result window 55 indicating that the document file 31 is normal. In the process of step S6, the verification result window 55 as shown in FIG. 7 is formed on the screen of the display unit 14. For example, in the verification result window 55, a message indicating that the document file 31 has not been tampered with and the time indicated by the time information 36 included in the time stamp token 33 attached to the document file 31 are displayed. Further, in the present embodiment, the message that the signature 40 of the digital certificate 37 is normal and the message that the digital certificate 37 is valid are not displayed in the verification result window 55 shown in FIG. 7. However, the user selects the tab 56 of the "verification result details" in the verification result window 55 to switch the display of the verification result window 55, so that the signature 40 of the electronic certificate 37 is normal and that the signature 40 is normal. It can be confirmed that the electronic certificate 37 is valid. The user can see the verification result window 55 and confirm that the document file 31 exists at the time of issuing the time stamp, has not been changed since that time, and the validity of the digital certificate 37 is recognized. can. Further, the user can close the verification result window 55 by pressing the OK button 59 in the verification result window 55 (step S9: “close”).

On the other hand, the arithmetic processing unit 11 is included in the hash value calculated in step S21 in FIG. 6 and the decrypted time stamp token information 34 from the comparison result and the determination result in the verification process stored in the temporary storage unit 12. The hash values 35 do not match each other, the expiration date of the digital certificate 37 has expired, the signature 40 of the digital certificate 37 is not normal, or the digital certificate 37 has not exceeded the expiration date. When it is recognized that the document file 31 is invalid, that is, the document file 31 is not normal, the fact that the document file 31 is not normal is displayed on the screen of the display unit 14 (step S5: NO, step S7). ..

Here, FIG. 8 shows a verification result window 61 indicating that the document file 31 is not normal. In the process of step S7, the verification result window 61 as shown in FIG. 8 is formed on the screen of the display unit 14. For example, in the verification result window 61, in addition to a message indicating whether or not the document file 31 has been tampered with, a message indicating that the signature 40 of the digital certificate 37 is not normal or a message indicating that the digital certificate 37 is not valid is displayed. Is displayed. Further, the user can confirm the details of the verification result by selecting the tab 56 of the "details of the verification result" in the verification result window 61 and switching the display of the verification result window 61. The user can see the verification result window 61 and confirm that the document file 31 has been tampered with or that the validity of the digital certificate 37 is not recognized. Further, the user can close the verification result window 61 by pressing the OK button 59 in the verification result window 61 (step S8: YES).

Further, when the arithmetic processing unit 11 recognizes that the document file 31 is normal from the comparison result and the determination result in the verification process stored in the temporary storage unit 12, the document file 31 is as shown in FIG. Form a tab 57 of "time stamp comparison / output" in the verification result window 55 indicating that is normal. When the document file 31 is normal, the user can output the time stamp token file 41 and compare the time stamp tokens by selecting the tab 57 of this "time stamp comparison / output". can.

On the other hand, when the arithmetic processing unit 11 recognizes that the document file 31 is not normal from the comparison result and the determination result in the verification process stored in the temporary storage unit 12, the document file 31 is as shown in FIG. Does not form a "timestamp comparison / output" tab in the verification result window 61 indicating that is not normal. As a result, when the document file 31 is not normal, the user cannot output the time stamp token file 41 and cannot compare the time stamp tokens. A tab of "timestamp comparison / output" is formed in the verification result window 61 indicating that the document file 31 is not normal, but this tab is grayed out and the user cannot select this tab. You may do it.

When the user selects the tab 57 of the "time stamp comparison / output" formed in the verification result window 55 indicating that the document file 31 is normal, the arithmetic processing unit 11 is, for example, as shown in FIG. A process selection window 65 is formed in the screen of the display unit 14. The process selection window 65 is a window for the user to select which of the output of the time stamp token file 41 and the comparison of the time stamp tokens should be performed. A time stamp token file output button 66 and a time stamp token comparison button 67 are formed in the process selection window 65. The user can output the time stamp token file 41 by pressing the time stamp token file output button 66, and can compare the time stamp tokens by pressing the time stamp token comparison button 67.

When the user presses the time stamp token file output button 66 (step S9: “output”), the time stamp token output processing unit 25 executes a process of outputting the time stamp token file 41. That is, first, the time stamp token output processing unit 25 duplicates the time stamp token 33 added to the document file 31 designated by the document file designation unit 21 (step S10). Then, the time stamp token output processing unit 25 generates a time stamp token file 41 including a copy of the time stamp token 33 as shown in FIG.

Subsequently, the time stamp token output processing unit 25 designates the storage location (second storage location) of the time stamp token file 41 according to the user's designated input (step S11). That is, the time stamp token output processing unit 25 forms a window on the screen of the display unit 14 for the user to specify and input the storage location of the time stamp token file 41. Then, after the user operates the operation unit 13 to input the storage location for storing the time stamp token file 41 in the window, the time stamp token output processing unit 25 sets the input storage location as the time stamp token. It is specified as the storage location of the file 41. For example, the user can specify a desired location in the external storage unit 16 as the storage location of the time stamp token file 41. Further, the user designates an arbitrary storage location in the USB memory connected to the user terminal 6 or the optical disk inserted in the optical disk drive provided in the user terminal 6 as the storage location of the time stamp token file 41. You can also do it.

Subsequently, the time stamp token output processing unit 25 stores the time stamp token file 41 in the storage location specified in step S11 (step S12). The user transmits the time stamp token file 41 stored in the designated storage location from the user terminal 6 to the time stamp storage server 5 via the computer network 7, and sends the time stamp token file 41 to the time stamp storage organization. Can be deposited and stored in.

On the other hand, when the user presses the time stamp token comparison button 67 in the process selection window 65 shown in FIG. 9 (step S9: “comparison”), the time stamp token comparison processing unit 26 compares the time stamp tokens. To execute. That is, first, the time stamp token comparison processing unit 26 forms a window on the screen of the display unit 14 for the user to specify the time stamp token file 41 stored in the external storage unit 16. The time stamp token file 41 is mainly assumed to be transmitted from the time stamp storage organization and stored in the external storage unit 16 of the user terminal 6, but other time stamp token files 41 may be used. .. The user operates the operation unit 13 and specifies an arbitrary time stamp token file 41 stored in the external storage unit 16. The time stamp token comparison processing unit 26 designates the time stamp token file 41 according to such a designated input by the user, and reads the designated time stamp token file 41 into the temporary storage unit 12 (step S13).

Subsequently, the time stamp token comparison processing unit 26 uses the time stamp token file 41 specified in step S13 and the time stamp token 33 added to the document file 31 designated by the document file specification unit 21 in step S1. Compare (step S14). In this comparison, the entire time stamp token file 41 and the entire time stamp token 33 may be compared, or the corresponding parts of the time stamp token file 41 and the time stamp token 33 may be compared with each other (for example, the time stamp token). Information (or hash values) may be compared.

Subsequently, the time stamp token comparison processing unit 26 displays the result of comparison between the time stamp token file 41 and the time stamp token 33 on the screen of the display unit 14 (step S15). FIG. 10 shows a window showing the result of comparison between the time stamp token file 41 and the time stamp token 33. That is, the window 71 in FIG. 10 is a window when the time stamp token file 41 and the time stamp token 33 match, and the window 72 does not match the time stamp token file 41 and the time stamp token 33. Case window. The coincidence between the time stamp token file 41 and the time stamp token 33 is that the document file 31 specified by the user in step S1 in FIG. 4 and the time stamp token file 41 specified by the user in step S13 are mutually matched. It means that it corresponds. The discrepancy between the time stamp token file 41 and the time stamp token 33 is that the document file 31 specified by the user in step S1 in FIG. 4 and the time stamp token file 41 specified by the user in step S13 are mutually exclusive. It means that it does not correspond. By looking at the window 71 or 72 shown in FIG. 10, the user sees whether or not the document file 31 specified in step S1 in FIG. 4 and the time stamp token file 41 specified in step S13 correspond to each other. Can be confirmed.

Even after the output processing of the time stamp token file 41 and the comparison processing of the time stamp tokens are completed, the user can continue the work of confirming the contents of the document data 32 in the document viewing screen 51. Then, when the user inputs an instruction to end the display of the document data to the user terminal 6 (step S16: YES), the arithmetic processing unit 11 ends the document file viewing process accordingly.

(Setting the validity judgment method of the digital certificate)
Further, in the above verification process, the user terminal 6 determines the validity of the digital certificate 37 included in the time stamp token 33 attached to the document file 31 from among a plurality of determination methods. It has a function to set according to the specification of.

The plurality of judgment methods are as follows. That is, the first determination method is that (a) the digital certificate 37 included in the time stamp token 33 attached to the document file 31 is within the expiration date, and (b) it is added to the document file 31. The signature 40 of the digital certificate 37 included in the time stamp token 33 is normal, and (c) the digital certificate 37 included in the time stamp token 33 attached to the document file 31 has an expiration date. The validity of the digital certificate 37 included in the time stamp token 33 attached to the document file 31 is recognized when any one of the predetermined ones that has not been revoked for a reason other than the excess of the above is satisfied. It is a method to judge that it is possible. The second determination method is the electron included in the time stamp token 33 added to the document file 31 when any two of the above conditions (a), (b) and (c) are satisfied. This is a method for determining that the validity of the certificate 37 is recognized. The third determination method is that the validity of the digital certificate 37 included in the time stamp token 33 attached to the document file 31 when all of the above conditions (a), (b) and (c) are satisfied is determined. It is a method to judge that it is accepted.

For example, the user can operate the operation unit 13 to specify in advance any one of the plurality of determination methods. The determination method setting unit 24 of the user terminal 6 sets any one of the plurality of determination methods according to the user's designation. Then, the verification unit 23 performs the verification process according to the determination method set by the determination method setting unit 24.

For example, if the first determination method is set to determine that the validity of the digital certificate 37 is recognized when only the above condition (a) is satisfied, the verification process is shown in FIG. Steps S21 and S22 are executed, and steps S23 and S24 are not executed. Then, as a result of the verification process, the hash value calculated in step S21 in FIG. 6 and the hash value 35 included in the decrypted time stamp token information 34 match each other, and the digital certificate 37 is valid. When the deadline has not been exceeded, the output processing of the time stamp token file 41 or the execution processing of the time stamp token comparison processing is permitted. On the other hand, as a result of the verification process, the hash value calculated in step S21 in FIG. 6 and the hash value 35 included in the decrypted time stamp token information 34 do not match each other, or the digital certificate 37 When the expiration date has expired, neither the execution of the output process of the time stamp token file 41 nor the execution of the time stamp token comparison process is permitted. Further, for example, when a method for determining that the validity of the digital certificate 37 is recognized when only the above conditions (a) and (b) are satisfied as the second determination method is set, verification is performed. In the process, steps S21, S22 and S23 in FIG. 6 are executed, and step S24 is not executed. Then, as a result of the verification process, the hash value calculated in step S21 in FIG. 6 and the hash value 35 included in the decrypted time stamp token information 34 match each other, and the expiration date of the digital certificate 37 Is not exceeded and the signature 40 of the digital certificate 37 is normal, the output processing of the time stamp token file 41 or the comparison processing of the time stamp token is permitted. If not, the time is not exceeded. Neither the execution of the output process of the stamp token file 41 nor the execution of the time stamp token comparison process is permitted. When the third determination method is set, steps S21, S22, S23 and S24 in FIG. 6 are executed in the verification process as described above. Then, as a result of the verification process, the hash value calculated in step S21 in FIG. 6 and the hash value 35 included in the decrypted time stamp token information 34 match each other, and the expiration date of the digital certificate 37 Is not exceeded, the signature 40 of the digital certificate 37 is normal, and the digital certificate 37 has not been revoked for any reason other than the expiration date, the output processing of the time stamp token file 41 or Execution of the time stamp token comparison process is permitted, otherwise execution of the output process of the time stamp token file 41 and execution of the time stamp token comparison process are not permitted.

As described above, according to the user terminal 6 which is the embodiment of the time stamp management device and the electronic file viewing device, the user can use the time stamp token file including the copy of the time stamp token 33 attached to the document file 31. 41 can be easily obtained. As a result, when using the time stamp storage service, the user only needs to store the time stamp token file 41 in the time stamp storage organization, so that the time stamp storage service can be easily used.

Further, the user terminal 6 compares the time stamp token file 41 with the time stamp token 33 added to the document file 31, and outputs the result of the comparison. As a result, the user can confirm the correspondence between the document file 31 and the time stamp token file 41. This configuration is useful, for example, when selecting the document file 31 corresponding to the time stamp token file 41 transmitted from the time stamp storage organization from a large number of document files 31.

Further, the user terminal 6 compares the calculated hash value (current hash value) with the hash value 35 (hash value at the time of issuing the time stamp) included in the time stamp token information 34 in the verification process. When the two do not match, that is, when the document file 31 has been tampered with, the output processing of the time stamp token file 41 is not performed. As a result, the time stamp token file 41 corresponding to the falsified document file 31 is not stored in the external storage unit 16 or the like. As a result, it is possible to prevent the user from storing the time stamp token file 41 corresponding to the falsified document file 31 in the time stamp storage organization. For example, the quality of time stamp management can be improved by storing only the time stamp token file 41 corresponding to the document file 31 that has not been tampered with in the time stamp storage organization.

Further, in the verification process, the user terminal 6 determines the validity of the digital certificate 37 included in the time stamp token 33 attached to the document file 31, and the validity of the digital certificate 37 is not recognized. In this case, the output processing of the time stamp token file 41 is not performed. As a result, the time stamp token file 41 corresponding to the document file 31 to which the electronic certificate 37 whose validity is not recognized is not stored in the external storage unit 16 or the like. As a result, it is possible to prevent the user from storing the time stamp token file 41 corresponding to the document file 31 to which the digital certificate 37 whose validity is not recognized is attached in the time stamp storage organization. For example, the quality of time stamp management can be improved by storing only the time stamp token file 41 corresponding to the document file 31 to which the valid digital certificate 37 is attached in the time stamp storage organization. can.

Further, the user terminal 6 does not perform the comparison process of the time stamp token 33 when the document file 31 is falsified or the validity of the digital certificate 37 is not recognized. As a result, it is possible to prevent meaningless comparison processing between the time stamp token 33 of the falsified document file 31 and the time stamp token file 41. Further, since meaningless comparison processing is prevented, the user can efficiently and quickly confirm the correspondence between the document file 31 and the time stamp token file 41.

Further, in the verification process, the user terminal 6 determines the validity of the digital certificate 37 included in the time stamp token 33 attached to the document file 31 from among a plurality of determination methods. Set according to the specification. According to this configuration, the strictness of the validity judgment of the digital certificate 37 can be set in a plurality of stages based on the user's designation. For example, by setting a loose first determination method, the time required for the validity determination process of the digital certificate 37 is shortened. As a result, the user can quickly acquire the time stamp token file 41. Further, by setting a strict third determination method, the time stamp token file 41 corresponding to the digital certificate 37 whose validity is not recognized by the strict conditions is not output. As a result, the user can store only the time stamp token file 41 corresponding to the digital certificate 37 whose validity is recognized by strict conditions in the time stamp storage organization, and the quality of time stamp management is greatly improved. Can be improved. Further, by setting the second determination method, the validity determination of the digital certificate 37 can be flexibly performed according to the actual situation. For example, in order to make the determination of the above condition (c), the user terminal 6 must access the electronic authentication authority. Therefore, the above condition (c) cannot be determined in the offline state in which the user terminal 6 is not connected to the computer network 7. On the other hand, the determination of the above conditions (a) and (b) can be performed even when the user terminal 6 is offline. By setting the judgment method for judging that the validity of the digital certificate 37 possessed by the document file 31 is recognized when the above conditions (a) and (b) are satisfied, the validity judgment of the digital certificate 37 can be judged offline. It becomes possible to execute in the state.

In the above-described embodiment, if the document file 31 is falsified as a result of the verification process or the validity of the digital certificate 37 is not recognized, the output process of the time stamp token file 41 is not performed. However, the present invention is not limited to this. Even if the document file 31 is falsified or the validity of the digital certificate 37 is not recognized, the time stamp token file 41 may be output. Further, in the above-described embodiment, if the document file 31 is falsified as a result of the verification process or the validity of the digital certificate 37 is not recognized, the time stamp token comparison process is not performed. The present invention is not limited to this. Even if the document file 31 has been tampered with or the validity of the digital certificate 37 is not recognized, the time stamp token comparison process may be performed.

Further, in the above-described embodiment, the case where the output processing of the time stamp token file 41 and the comparison processing of the time stamp tokens are performed in the browsing process of the document file 31 has been given as an example, but the present invention is not limited to this. .. The output process of the time stamp token file 41 or the comparison process of the time stamp token may be separated from the browsing process of the document file 31. For example, an item for output processing of the time stamp token file 41 or comparison processing of the time stamp token is provided in the context menu displayed when the user right-clicks the unopened document file 31 with the mouse and specifies it. When the user specifies this item, the time stamp token file 41 may be output or the time stamp token comparison process may be executed.

Further, in the above-described embodiment, the case where the electronic file that is the target of the output processing of the time stamp token file 41 or the comparison processing of the time stamp token is the document file 31 is taken as an example. However, the electronic file is, for example, an image. It may be a file, a graphic file, an audio file, a video file, or the like.

Further, in the above-described embodiment, the document file designation unit 21 is a specific example of the electronic file designation unit in the description of the claims. Further, the verification unit 23 is a specific example of the hash value comparison unit and the certificate validity determination unit in the description of the claims. Further, the time stamp token output processing unit 25 is a specific example of the time stamp token duplication unit, the storage location designation unit, and the time stamp token file output unit in the description of the claims. Further, the time stamp token comparison processing unit 26 is a specific example of the time stamp token file comparison unit in the description of the claims.

Further, the present invention can be appropriately modified within the scope of claims and within a range not contrary to the gist or idea of the invention that can be read from the entire specification, and a time stamp management device, an electronic file viewing device and an electronic file viewing device accompanied by such a change. The program is also included in the technical idea of the present invention.

INDUSTRIAL APPLICABILITY The present invention can be used as a means for extracting a time stamp token from an electronic file when storing the time stamp token attached to the electronic file in a time stamp storage organization.

1 Time authentication system 5 Time stamp storage server 6 User terminal (time stamp management device, electronic file viewing device)
11 Arithmetic processing unit 16 External storage unit (first storage location, second storage location)
21 Document file designation section (electronic file designation section)
22 Display control unit 23 Verification unit (hash value comparison unit, certificate validity judgment unit)
24 Judgment method setting unit 25 Time stamp token output processing unit (time stamp token duplication unit, storage location specification unit, time stamp token file output unit)
26 Timestamp token comparison processing unit (Timestamp token file comparison unit)
31 Document file (electronic file)
32 Document data (main data)
33 Timestamp Token 34 Timestamp Token Information 35 Hash Value 36 Time Information 37 Digital Certificate 41 Timestamp Token File

Claims (9)

It has a main data, a hash value of the main data, time information given by the time certification body, and a time stamp token containing the digital certificate of the time certification body, and is stored in the first storage location. The electronic file specification part that specifies the electronic file and the electronic file specification part
Hash value comparison that calculates the hash value of the main data of the electronic file and compares the calculated hash value with the hash value of the main data included in the time stamp token of the electronic file. Department and
A time stamp token duplication unit that duplicates the time stamp token included in the electronic file designated by the electronic file designation unit, and a time stamp token duplication unit.
A storage location specification unit that specifies a second storage location,
A time stamp token file including the time stamp token duplicated by the time stamp token duplication unit is generated, and the generated time stamp token file is placed in the second storage location designated by the storage location designation unit. and a timestamp token file output unit that stores,
As a result of comparison by the hash value comparison unit, when the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file match each other, the display device is used. When the time stamp token file output button is displayed on the screen and the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit outputs the time stamp token file. Generate and store the generated time stamp token file in the second storage location designated by the storage location designation unit.
As a result of comparison by the hash value comparison unit, if the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file do not match each other, the electronic file A time stamp management device, characterized in that the fact that is not normal is displayed on the screen of the display device, and the time stamp token file output button cannot be displayed or pressed on the screen of the display device. It has a main data, a hash value of the main data, time information given by the time certification body, and a time stamp token containing the digital certificate of the time certification body, and is stored in the first storage location. The electronic file specification part that specifies the electronic file and the electronic file specification part
A certificate validity determination unit that determines whether or not the validity of the digital certificate included in the time stamp token of the electronic file is recognized, and
A time stamp token duplication unit that duplicates the time stamp token included in the electronic file designated by the electronic file designation unit, and a time stamp token duplication unit.
A storage location specification unit that specifies a second storage location,
A time stamp token file including the time stamp token duplicated by the time stamp token duplication unit is generated, and the generated time stamp token file is placed in the second storage location designated by the storage location designation unit. Equipped with a time stamp token file output unit to store
As a result of the determination by the certificate validity determination unit, if the validity of the electronic certificate included in the time stamp token possessed by the electronic file is confirmed, the time stamp token file is displayed on the screen of the display device. When the output button is displayed and the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit generates the time stamp token file, and the generated time stamp token file is generated. The time stamp token file is stored in the second storage location designated by the storage location designation unit, and the time stamp token file is stored in the second storage location.
As a result of the determination by the certificate validity determination unit, if the validity of the electronic certificate included in the time stamp token possessed by the electronic file is not confirmed, the electronic file is not normal. A time stamp management device that is displayed on the screen of a display device and that the time stamp token file output button cannot be displayed or pressed on the screen of the display device. It is provided with a time stamp token file comparison unit that compares the time stamp token included in the electronic file with the time stamp token file and outputs the result of the comparison.
As a result of comparison by the hash value comparison unit, when the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file match each other, the display device When the time stamp token file output button and the time stamp token comparison button are displayed on the screen of, and the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit causes the time stamp token file output unit. The time stamp token file is generated, the generated time stamp token file is stored in the second storage location designated by the storage location designation unit, and the time stamp token comparison displayed on the screen of the display device. When the button is pressed, the time stamp token file comparison unit compares the time stamp token included in the electronic file with the time stamp token file, and outputs the result of the comparison.
As a result of comparison by the hash value comparison unit, if the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file do not match each other, the electronic file Is displayed on the screen of the display device, and the time stamp token file output button and the time stamp token comparison button cannot be displayed or pressed on the screen of the display device. Item 1. The time stamp management device according to item 1. It is provided with a time stamp token file comparison unit that compares the time stamp token included in the electronic file with the time stamp token file and outputs the result of the comparison.
As a result of the determination by the certificate validity determination unit, if the validity of the electronic certificate included in the time stamp token possessed by the electronic file is confirmed, the time stamp token is displayed on the screen of the display device. When the file output button and the time stamp token comparison button are displayed and the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit outputs the time stamp token file. When the generated time stamp token file is stored in the second storage location designated by the storage location designation unit, and the time stamp token comparison button displayed on the screen of the display device is pressed. , The time stamp token file comparison unit compares the time stamp token included in the electronic file with the time stamp token file, and outputs the result of the comparison.
As a result of the determination by the certificate validity determination unit, if the validity of the electronic certificate included in the time stamp token possessed by the electronic file is not confirmed, the electronic file is not normal. The time according to claim 2, wherein the time is displayed on the screen of the display device, and the time stamp token file output button and the time stamp token comparison button cannot be displayed or pressed on the screen of the display device. Stamp management device. The certificate validity determination unit is that (a) the electronic certificate included in the time stamp token of the electronic file is within the expiration date, and (b) the time stamp of the electronic file. For reasons other than that the signature of the electronic certificate contained in the token is normal, and (c) the electronic certificate contained in the time stamp token of the electronic file has expired. A first determination method for determining that the validity of the electronic certificate included in the time stamp token of the electronic file is recognized when any one of the predetermined ones that has not been revoked is satisfied. And, when any two of the conditions (a), (b) and (c) are satisfied, the validity of the electronic certificate included in the time stamp token of the electronic file is determined. The second determination method for determining that the electronic file is acceptable, and the electronic certificate included in the time stamp token of the electronic file when all of the conditions (a), (b) and (c) are satisfied. Of the third determination method for determining that the validity is recognized, the validity of the electronic certificate included in the time stamp token of the electronic file is determined by any of the determination methods specified by the user. The time stamp management device according to claim 2 or 4, wherein the time stamp is determined. It has a main data, a hash value of the main data, time information given by the time certification body, and a time stamp token containing the digital certificate of the time certification body, and is stored in the first storage location. The electronic file specification part that specifies the electronic file and the electronic file specification part
A display control unit that displays the contents of the main data of the electronic file designated by the electronic file designation unit on the screen of the display device, and a display control unit.
Hash value comparison that calculates the hash value of the main data of the electronic file and compares the calculated hash value with the hash value of the main data included in the time stamp token of the electronic file. Department and
A time stamp token duplication unit that duplicates the time stamp token included in the electronic file designated by the electronic file designation unit, and a time stamp token duplication unit.
A storage location specification unit that specifies a second storage location,
A time stamp token file including the time stamp token duplicated by the time stamp token duplication unit is generated, and the generated time stamp token file is placed in the second storage location designated by the storage location designation unit. Equipped with a time stamp token file output unit to store
As a result of comparison by the hash value comparison unit, when the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file match each other, the display device When the time stamp token file output button is displayed on the screen of, and the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit causes the time stamp token file. Is generated, and the generated time stamp token file is stored in the second storage location designated by the storage location designation unit.
As a result of comparison by the hash value comparison unit, if the calculated hash value and the hash value of the main data included in the time stamp token of the electronic file do not match each other, the electronic file An electronic file viewing device, characterized in that the fact that is not normal is displayed on the screen of the display device, and the time stamp token file output button cannot be displayed or pressed on the screen of the display device. It has a main data, a hash value of the main data, time information given by the time certification body, and a time stamp token containing the digital certificate of the time certification body, and is stored in the first storage location. The electronic file specification part that specifies the electronic file and the electronic file specification part
A display control unit that displays the contents of the main data of the electronic file designated by the electronic file designation unit on the screen of the display device, and a display control unit.
A certificate validity determination unit that determines whether or not the validity of the digital certificate included in the time stamp token of the electronic file is recognized, and
A time stamp token duplication unit that duplicates the time stamp token included in the electronic file designated by the electronic file designation unit, and a time stamp token duplication unit.
A storage location specification unit that specifies a second storage location,
A time stamp token file including the time stamp token duplicated by the time stamp token duplication unit is generated, and the generated time stamp token file is placed in the second storage location designated by the storage location designation unit. Equipped with a time stamp token file output unit to store
As a result of the determination by the certificate validity determination unit, if the validity of the electronic certificate included in the time stamp token of the electronic file is confirmed, the time stamp token is displayed on the screen of the display device. When the file output button is displayed and the time stamp token file output button displayed on the screen of the display device is pressed, the time stamp token file output unit generates the time stamp token file and generates the time stamp token file. The time stamp token file is stored in the second storage location designated by the storage location designation unit.
As a result of the determination by the certificate validity determination unit, if the validity of the electronic certificate included in the time stamp token possessed by the electronic file is not confirmed, the electronic file is not normal. An electronic file viewing device that is displayed on the screen of a display device and that the time stamp token file output button cannot be displayed or pressed on the screen of the display device. A program for operating a computer as the time stamp management device according to any one of claims 1 to 5. A program for operating a computer as the electronic file viewing device according to claim 6 or 7.

Images