JPH1185017A - Digital signature apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable addition of a digital signature to data by converting the display contents to be added with the digital signature to a standardized format of a data form and a display method of text, images, etc. SOLUTION: Documents are edited by an edition section 103 while refering to the contents to be displayed on a display section 102 in a digital signature apparatus 101. When editing ends, the document contents are converted to a signature acquirable form by a data-to-be-signed conversion section 106. A digital signature forming section 107 forms the digital signature from the converted data. The formed data is added to the data to be signed and is converted to a save form by a save form conversion section 104. This data is saved by a saving section 105 after the conversion. The apparatus is provided with the means for converting the information to the digital signature acquirable form according thereto and, therefore, the acquisition of the digital signature with the multimedia information with which the acquisition of the digital signature is difficult is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing system in which a digital signature device is connected to a network and a document generated by the digital signature device is exchanged between the digital signature devices. The present invention relates to a digital signature device for guaranteeing that a digital signature is verified and preventing falsification of a document.

[0002]

2. Description of the Related Art FIG. 16 shows components of a digital signature processing apparatus for performing a conventional digital signature process. In the figure, a digital signature device 1601 is displayed on a display unit 16 for displaying a document.
02, an editing unit 1603 for editing a document, a storage format conversion unit 1604 for converting a document into a storage format, a storage unit 1605 for storing a document, a digital signature generation unit 1606 for generating a digital signature, and a digital signature verification for verifying the digital signature It comprises a unit 1607.

FIG. 17 is a flowchart showing the flow of a digital signature generation process in the digital signature device.

Hereinafter, a digital signature generation process of the digital signature device will be described with reference to the drawings. As shown in FIG. 17, in the digital signature device 1601, the display unit 1602
The document is edited by the editing unit 1603 while referring to the contents displayed in step S1701. When the editing is completed, the document content is converted by the storage format conversion unit 1604.
It is converted into a storage format (step S1702). The digital signature generation unit 1606 generates a digital signature from the document in the storage format (step S1703), and adds the generated digital signature to the document in the storage format (step S170).
4) The storage unit 1605 stores the document in the storage format to which the digital signature has been added (step S1705).

FIG. 18 is a flowchart showing the flow of a digital signature verification process in the digital signature device.

Hereinafter, the digital signature verification processing of the digital signature device will be described with reference to the drawings. As shown in FIG. 18, in the digital signature device 1601, the digital signature verifying unit 1607 obtains the document in the storage format stored in the storage unit 1605 and its digital signature (step S1801). The digital signature is verified using the digital signature (step S180)
2).

[0007]

In the digital signature processing in the conventional document processing, a digital signature is generated from a file as a storage format such as an MS-Word doc file and an MS-Excel xls file.
As a result, the falsification check of the file can be realized, but the same file can be displayed differently by falsifying the application program that displays the contents of the file. Therefore, it is not enough to add a digital signature to a file in the storage format in order to prevent falsification of the signed content, and it is necessary to apply a digital signature to the program that displays the file in the storage format. is there. However, recent programs are large,
There is a problem that the configuration is complicated, the version is frequently updated, and it is difficult to obtain a digital signature from the program.

[0008] In recent years, such as an online shopping system, a system for assuring that a user has approved the content by giving the user a digital signature on the purchased item, the amount of money, the payment method, and the like. There is. In such a system, it is difficult for the user to accurately grasp the data to which the user has added the digital signature. So, malicious service providers,
There is a problem that it is possible to add a digital signature to contents different from what the user sees on the screen.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and converts a display content to which a digital signature is added into a data format such as a text or an image and a standardized format of a display method. A digital signature device capable of adding a digital signature to the converted data is provided.

[0010]

A digital signature device according to the present invention converts a display content into a format in which a digital signature can be obtained, a digital signature from the converted display content information, and a display content. To a storage format, and a unit for storing display contents in the storage format.

[0011] Further, there is provided a means for acquiring a document with a digital signature in a storage format stored in the storage means and verifying the digital signature using the digital signature acquisition target format document and the digital signature.

There is provided a means for converting display contents into a text format and generating a digital signature from the converted text display contents.

There is provided a means for converting the display content into a text format composed of a set of an attribute name and an attribute value, and generating a digital signature from the converted text-format display content.

There is provided means for converting display contents into an image and generating a digital signature from the converted display contents in the image format.

Further, when signing the contents of the circulation document, there is provided means for presenting the converted signing target information to the signer.

Further, in the digital signature device according to the present invention, the transmitting digital signature device includes means for editing a document, means for displaying the document, means for converting the document into a storage format, and a method for storing the document in the storage format. Means for receiving the document in the transmission format, means for converting the document in the transmission format to a signature target format,
The digital signature included in the document in the signature target format and the digital signature included in the transmission format document; a unit for converting the transmission format document into a storage format; and a unit for storing the storage format document. It is a thing.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, Embodiment 1 of the present invention will be described. FIG. 1 is a diagram illustrating a configuration of a digital signature device according to a first embodiment of the present invention. Reference numeral 101 denotes a digital signature device that converts a display content into a format in which a digital signature can be obtained, and then generates and adds a digital signature. It is.

In the figure, a digital signature device 101
A display unit 102 for displaying information to a user; an editing unit 103 for editing information; a storage format conversion unit 104 for converting information into a storage format; a storage unit 105 for storing information; It is composed of a signature target data conversion unit 106 for converting the data into a format, a digital signature generation unit 107 for generating a digital signature of the data converted by the signature target data conversion unit 106, and a digital signature verification unit 108 for verifying the digital signature. Have been.

FIG. 2 is a flowchart showing the flow of a digital signature generation process in the digital signature device.

Hereinafter, the digital signature generation processing of the digital signature device will be described with reference to the drawings. As shown in FIG. 2, in the digital signature device 101, the document is edited by the editing unit 103 while referring to the content displayed on the display unit 102 (step S201). Upon completion of the editing, the document content is converted by the signature target data conversion unit 106 into a signature obtainable format (step S202). The digital signature generation unit 107 generates a digital signature from the data converted in step S202 (step S2).
03). The generated digital signature is added to the signature target data (step S204), and the storage format conversion unit 104
After conversion into the storage format, the data is stored by the storage unit 105 (step S205).

FIG. 3 is a flowchart showing the flow of a digital signature verification process in the digital signature device.

Hereinafter, the digital signature verification processing of the digital signature device will be described with reference to the drawings. As shown in FIG. 3, in the digital signature device 101, the digital signature verifying unit 108 acquires the document with the digital signature in the storage format stored in the storage unit 105 (step S30).
1) The digital signature is verified using the digital signature acquisition target format document and the digital signature (step S30).
2).

As described above, according to the first embodiment, since the means for converting information into a digital signature acquirable format is provided, a digital signature is applied to multimedia information for which it is difficult to acquire a digital signature. It becomes possible to acquire.

Embodiment 2 FIG. In the digital signature device according to the second embodiment of the present invention, a case will be described in which the document content is represented by an attribute name and an attribute value and both the attribute name and the attribute value are converted to text by the signature conversion unit 106.

In FIG. 4, the information input by the user is:
The information is “Ken Yoneda” and “Y-shirt”, and the information selected by the user is the number “3”. All other information is displayed by the application program. The process of adding a digital signature to the display content by the user is performed according to the flow shown in FIG. At that time, in the conversion of the signature target data in step S202, the display contents are converted into a series of lines in which three elements of “attribute name”, “:”, and “attribute value” are expressed in text. The attribute names are "Name", "Order", "Quantity", "Unit Price", and "Total Amount"
The attribute values corresponding to the attribute name are “Ken Yoneda”, “Y-shirt”, “3”, “7500 yen”, and “22,500 yen”.

In FIG. 5, the user sets two grades “Taro Yamada” and “Shigeru Moriyama” as a grade table in spreadsheet software.
Enter the score of "language" and "arithmetic". The process of adding a digital signature to this grade table for falsification check and creation confirmation is performed according to the flow shown in FIG. At this time, in the conversion of the signature target data in step S202, the display content is changed to “attribute name” “:”
Three elements called "attribute values" are converted to a line of text. In the example of FIG. 5, the attribute names are further expressed in text representation of three elements of "person name", ".", And "subject". The attribute names are “Taro Yamada. Japanese”, “Taro Yamada. Arithmetic”, “Shigeru Moriyama. Japanese”, “Shigeru Moriyama. Arithmetic”, and the attribute value corresponding to the attribute name is “7”.
3 "," 80 "," 58 ", and" 93 ".

FIG. 6 shows a state of generation of a conventional file with a digital signature, and FIG. 7 shows a state of generation of a file with a digital signature obtained as a result of the second embodiment. As shown in FIG. 6, in a conventional process of generating a file with a digital signature, a file of a different format is generated for each application program, a digital signature is generated from the generated file, and the generated digital signature is added to the file. Added and saved. Therefore, in order to confirm the data for which the digital signature was obtained,
Each application that has generated a file is required, and as a result, a tampering check process is also required for each application. In the case of an application in which the display contents of the application are not saved as a file, a digital signature cannot be added to the display contents. However, as shown in FIG. 7, according to the process of generating a file with a digital signature according to the second embodiment, by providing a portion for converting a signature target into a format in which an attribute name and an attribute value are expressed in text, a different application is provided. Can be converted to a signature target format in a common format called a text format. As a result, in order to confirm the data subject to signature,
All you need is a text display application. Also, since the text format and its display method are simple and standardized, it is possible to omit the falsification check for the text display application.

As described above, according to the second embodiment, the data to be signed is converted into the text format, so that the application for displaying the signature content does not need to be tampered with, and the application that does not save the display content in a file is required. It is also possible to add a digital signature to the display contents of.

Embodiment 3 In the digital signature device according to the third embodiment of the present invention, a case will be described in which the document content is converted into an image by the signature conversion unit 106. In FIG. 8, the information input by the user is “Yoneda
“Ken” and “Y-shirt”, and the information selected by the user is the number “3”. All other information is displayed by the application program. The process of adding a digital signature to the display content by the user is performed according to the flow shown in FIG. At that time, step S202
In the conversion of the signature target data, the display content is converted into an image image.

As described above, according to the third embodiment, since the data to be signed is converted into an image, it is possible to add a digital signature to the display contents where the visual information is important. Also, since the image format and its display method are simple and standardized, it is possible to omit the tampering check for the image display application.

Embodiment 4 FIG. In the digital signature device according to the fourth embodiment of the present invention, the
The line information is converted into a format in which the attribute value and the attribute name are expressed in text, a digital signature is generated from the converted format, and the value of the digital signature is included in the storage format. FIG. 9 shows how the document saving process is performed in this case.

FIG. 10 is a diagram showing a flow of the document storing process shown in FIG. In FIG. 10, the digital signature device 101 first edits tabular data by the editing unit 103 (step S1001). After the editing, when the data is saved, each row of the table is converted into a format in which the attribute value and the attribute name are expressed in text (step S1002). Generate a digital signature from the converted data (step S
1003). In the storage format conversion unit 104, a column attribute of the digital signature is added to the edited data table, and a value of the digital signature is inserted for each row (step S10).
04), and then stored (step S1005).

As described above, according to the fourth embodiment, tabular data is converted into text for each row information, a digital signature of the converted data is generated, and the value of the digital signature is changed to the attribute value of the row. In addition, since the digital signature is stored for each line, the digital signature of each line can be verified, and the falsification of each line can be checked.

Embodiment 5 In the digital signature device according to the fifth embodiment of the present invention, when each circulator signs a display content in a document to be circulated, a signature target of each circulator is converted into a text format, and then the converted text is converted. Here, a case where a digital signature is generated from is described.

FIG. 11 shows that the circulation document has the signature target areas of the applicant, the section manager, and the section manager who are three circulation persons. The applicant name A and the application reason B are the information to be signed by the applicant. Applicant name A, Application reason B,
The section manager comment C is the section manager's signature target information. Applicant's name A, reason for application B, section manager's comment C, section manager's comment D
Is signature target information of the manager. In FIG. 11, it is shown that the information to be signed is converted into a format in which attribute names and attribute values are expressed in text, and that the digital signature generated from the converted text is included in the storage format. I have.

As described above, according to the fifth embodiment, when signing the contents of a circular document, the signing target of the signer is converted into a format in which attribute names and attribute values are expressed in text. By generating a digital signature of the circulation person from the converted information and storing the digital signature including the digital signature at the time of saving, each circulation person confirms the contents of his / her signature target and that the signature target is falsified. It is possible to verify that there is no.

Embodiment 6 FIG. In the digital signature device according to Embodiment 6 of the present invention, when a user adds a digital signature to display content, the display content is converted into text, and the text information is presented to the user, so that the digital signature is given to the user. A case will be described in which it is asked whether or not addition is possible.

FIG. 12 is a flowchart showing the flow of the signature adding process. In FIG. 12, the digital signature device 10
First, the editing unit 103 edits data (step S1201). After the editing is completed, the display content is converted to a text before the user adds the digital signature (step S).
1202). The converted text information is presented to the user (step S1203). The user who has seen the contents to be signed determines whether or not to sign (step S).
1204). If no signature is given, the signature adding process is terminated. If a signature is given, a digital signature is generated from the presented text information (step S1205), and the generated digital signature is added to the text information (step S1206). Is saved (step S1207).

As described above, according to the sixth embodiment, before the user signs the display content, the display content is converted into text, and the converted text information is presented to the user. It is possible to clearly understand the content of the signature.

Embodiment 7 Embodiment 7 of the present invention will be described. FIG. 13 is a diagram showing a configuration of a digital signature device according to Embodiment 7 of the present invention.
Reference numeral 1301 denotes a transmitting digital signature device, 1302 denotes a receiving digital signature device, and 1303 denotes a communication path.

The transmitting digital signature device 1301 includes a display unit 1304 for displaying information to a user, an editing unit 1305 for editing information, a storage format conversion unit 1306 for converting information into a storage format, and a storage for storing information. Part 1307;
A signature target data conversion unit 1308 that converts information into a signature obtainable format, a digital signature generation unit 1309 that generates a digital signature of the data converted by the signature target data conversion unit 1308, and a transmission format that converts the information into a transmission format It comprises a conversion unit 1310 and a transmission unit 1311 for transmitting information.

Also, the receiving digital signature device 1302
Is a receiving unit 1314 for receiving information, a signature target data conversion unit 1312 for converting information included in the reception information into a digital signature acquisition format, information converted by the signature target data conversion unit 1312, and the reception information. A digital signature verification unit 1313 that verifies the digital signature using the digital signature, a storage format conversion unit 1315 that converts received information into a storage format, and a storage unit 1316 that stores information in the storage format.

FIGS. 14 and 15 are flowcharts showing the processing of the digital signature unit 1301 on the transmitting side and the digital signature unit 1302 on the receiving side, respectively. Hereinafter, the operation of the digital signature devices 1301 and 1302 will be described with reference to the drawings.

As shown in FIG. 14, in the transmitting digital signature device 1301, the editing unit 1305 edits data (step S1401). Next, the signature target data conversion unit 1308 converts the edited data into a format in which the attribute name and the attribute value are expressed in text (Step S14).
02). A digital signature is generated from the converted data (step S1403), and the generated digital signature is
The data for which the digital signature is to be obtained is stored in the storage format converter 130.
6 (step S1404).
The converted data is stored by the storage unit 1307 (step S1).
405). After that, the generated digital signature and the data for which the digital signature is to be obtained are converted into a transmission format by the transmission format conversion unit 1310 (step S1406), and transmitted to the communication path 1303 (step S1407).

As shown in FIG. 15, in the receiving digital signature device 1302, the receiving unit 1314 receives data from the communication channel 1303 (step S1501). The signature target data in the transmission format included in the received data is converted by the signature target data conversion unit 1312 into a format in which the attribute name and the attribute value are expressed in a text format (step S1).
502). Next, the digital signature included in the received data is obtained (step S1503), and the digital signature verification unit 1313 verifies the digital signature using the digital signature (step S1504). After verifying the digital signature, the data to be signed and the digital signature are stored in the storage format conversion unit 1315.
(Step S1505), and stored by the storage unit 1306 (step S150).
6).

As described above, according to the seventh embodiment, the transmitting / receiving digital signature device has means for independently processing text format signature acquisition format data, transfer format data, and storage format data. I got a signature,
An optimal data format can be adopted for each of the transfer and storage processes, and the efficiency of each process can be increased.

[0047]

Since the present invention is configured as described above, it has the following effects.

Since the means for converting information into a format in which a digital signature can be obtained is provided, a digital signature can be obtained for multimedia information for which obtaining a digital signature is difficult.

Further, by converting the data to be signed into a text format, it is not necessary to perform a tampering check process on the application displaying the signature content, and the digital signature can be applied to the display content of the application that does not save the display content in a file. Can be added.

Further, by converting the data to be signed into an image, a digital signature can be added to the display contents in which the visual information is significant.

Further, when signing the contents of the circulation document, means for presenting the converted signing target information to the signer is provided, so that the circulated signers can confirm the contents of their own signing targets. It is possible to verify that the signature target has not been tampered with.

Further, the transmitting / receiving digital signature device is provided with means for independently processing text format signature acquisition format data, transfer format data, and storage format data. An optimal data format can be adopted for each processing of storage, and the efficiency of each processing can be increased.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a digital signature device according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a flow of a signature adding process in the digital signature device according to the first embodiment;

FIG. 3 is a flowchart illustrating a flow of a signature verification process in the digital signature device according to the first embodiment;

FIG. 4 is a diagram showing an example of text conversion of a signature target according to Embodiment 2 of the present invention.

FIG. 5 is a diagram illustrating another example of text conversion of a signature target according to the second embodiment.

FIG. 6 is a diagram showing a state of signing a file in a conventional example.

FIG. 7 is a diagram showing a state of signing a file according to the second embodiment.

FIG. 8 is a diagram showing an example of image conversion of a signature target according to Embodiment 3 of the present invention.

FIG. 9 is a diagram showing an example of text conversion of a signature target according to Embodiment 4 of the present invention.

FIG. 10 is a flowchart illustrating a flow of a signature adding process according to the fourth embodiment.

FIG. 11 is a diagram showing an example of text conversion of a signature target part in a circulation document according to Embodiment 5 of the present invention.

FIG. 12 is a flowchart showing a flow of a signature adding process according to the sixth embodiment of the present invention.

FIG. 13 is a diagram showing a configuration of a digital signature device according to a seventh embodiment of the present invention.

FIG. 14 is a flowchart showing a flow of processing of a digital signature device on the transmitting side according to the seventh embodiment.

FIG. 15 is a flowchart showing a flow of processing of a digital signature device on the receiving side according to the seventh embodiment.

FIG. 16 is a diagram showing a configuration of a conventional digital signature device.

FIG. 17 is a flowchart showing a flow of a signature adding process of a conventional digital signature device.

FIG. 18 is a flowchart showing a flow of a signature verification process of a conventional digital signature device.

[Explanation of symbols]

101 digital signature device, 102, 1304 display unit, 103, 1305 editing unit, 104, 1306, 13
15 storage format converter, 105, 1307, 1316
Storage unit, 106, 1308, 1312 Signature target data conversion unit, 107, 1309 Digital signature generation unit, 10
8, 1313 Digital signature verification unit, 1301 sender digital signature device, 1302 receiver digital signature device, 1303 communication channel, 1310 transmission format converter,
311 Transmitter, 1314 Receiver.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04L 9/32 H04L 9/00 673Z

Claims (7)

[Claims] 1. Signing data conversion means for converting display contents into a format in which a digital signature can be obtained, digital signature generation means for generating a digital signature from the display content information converted by the signing data conversion means, and display. A digital signature device comprising: a storage format conversion unit for converting contents into a storage format; and a storage unit for storing display contents in the storage format. 2. Signing data conversion means for converting display contents into a format in which a digital signature can be obtained, digital signature generation means for generating a digital signature from the display content information converted by the signature data conversion means, and display. A storage format conversion unit for converting the contents into a storage format, a storage unit for storing the display contents of the storage format, and a digital signature-acquired document in the storage format stored in the storage unit, and a digital signature acquisition target format document And a digital signature verifying means for verifying the digital signature using the digital signature. 3. The digital signature according to claim 1, wherein the digital signature generating means converts the display content into a text format, and generates a digital signature from the converted text format display content. apparatus. 4. The digital signature generating means converts a display content into a text format composed of a set of an attribute name and an attribute value, and generates a digital signature from the converted text format display content. Claim 1 or Claim 2
Digital signature device as described. 5. The digital signature device according to claim 1, wherein the digital signature generating means converts the display content into an image and generates a digital signature from the converted display content in the image format. . 6. A signature object information presenting means for presenting converted sign object information to a signer when signing the contents of a circulation document.
Digital signature device as described. 7. A document processing system for exchanging a document between digital signature devices, the transmitting digital signature device includes editing means for editing the document, display means for displaying the document, and a storage format for converting the document into a storage format. Conversion means, storage means for storing the document in the storage format, the receiving-side digital signature device includes a reception means for receiving the document in the transmission format, a data conversion means for the signature target for converting the document in the transmission format into a signature target format, a signature Digital signature verification means for verifying the digital signature from the target format document and the digital signature included in the transmission format document, storage format conversion means for converting the transmission format document into a storage format, and storage for storing the document in the storage format And a digital signature device.