JP2001022739A - Simple type document protecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower the readability of document contents to a 3rd person when it is difficult to incorporate a ciphering function because of export, cost, etc., or for a document system which need not to have a high function for security, an individually used information system which need not to invest in security measures, etc. SOLUTION: An application 11 converts regular font information which is stored in a font memory 17 or used as a system default into font information which is made unreasonable in the correspondence between character codes and character fonts when a user makes an indication by a font mask process part 13 or a certain time later through a timer monitor part 14 and prevents the information from being read by a 3rd person by a means which allows reversible conversion through the authentication of a password authentication part 16 by the user.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a personal computer, a portable terminal, etc., in which it is difficult to implement an encryption mechanism, or in a simple word processor or a simple document processing system having a low security level, a document data is transmitted to a third party. The present invention relates to a general system that requires a function of protecting from reading and browsing.

[0002]

2. Description of the Related Art Conventionally, when protecting the contents of document data including digitized character information, an electronic document data file is encrypted by using an encryption mechanism such as a secret key method or a public key encryption method. Or ISO 8879 (Standard Gen
eralized Markup Language (SGML)) or ISO / IEC 8613 (Op
en Document Architecture), which is protected by using encryption and decryption mechanisms based on encryption algorithms, such as using a protection mechanism for each structural element of a structured document such as a paragraph or paragraph. I have. On the other hand, as a protection method that does not use an encryption mechanism, as shown in JP-A-6-243121, a method in which a partial character string is replaced with a numeric string by a predetermined code table separately prepared, or a bar code is replaced. Alternatively, there is a method of replacing the character with a mosaic encryption character. The main purpose of these is to prevent literacy by a third party on a print medium (paper or the like), and hides only a partial character string. In addition, it is not effective because it is not considered when electronic storage is performed on a disk shared by a network. In addition, when a document stored electronically is protected, a protection mechanism using a password or the like is provided for the file. However, an additional protection mechanism is required when a password is disclosed to a third party.

[0003]

In the above prior art,
When leaving a computer in a document system that does not have a high demand for security functions, an information system for personal use that does not need to invest in security measures, or a low security policy, such as a popular word processor or portable terminal. Also, in the case of a portable terminal, the contents of a document may be easily read by a third party due to loss, theft, or the like. An object of the present invention is to provide means for preventing a third party from reading document data stored on a disk shared by the own system or a network having a low security function. In addition, the encryption mechanism has a problem of export and the like, and provides a mechanism for protecting document data by a simple protection mechanism, thereby providing a function to complement the mechanism.

[0004]

A document processing system or text editing processing system capable of editing and displaying document data stored in a disk of its own computer or a shared disk distributed on a network stores fonts in a memory. Means for converting regular font information in a memory into invalid font information, that is, font information in which a correspondence between a character code and a character font is statically or dynamically invalidated according to a user's instruction; Means for permitting reversible conversion by authentication of a password or the like by a user,
This is realized by providing a means for monitoring the presence or absence of a control command from the user in the processing system of the document data with a timer, and a means for automatically replacing the font with an invalid font when there is no control from the user for a set time. You.

[0005] An illegal font is sometimes registered by a user in advance or dynamically created by a user giving a parameter, and valid font information is deliberately displaced by intentionally displacing the array. It is characterized in that it is changed to an arbitrary character arrangement having no meaning.

[0006] As a parameter means for dynamically changing, a document creator uses his / her name as a key. A name is input in Roman characters, an offset value displaced from a constituent bit string is calculated, and the font arrangement is shifted.

As a means for preventing a file from being retrieved by a third party with respect to a file after the font mask is applied, the file management unit may use a file management table to apply the file name of the original document using the regular font and the illegal font in the file management table. The file management system provides a means for displaying any one of the file names according to a user's instruction.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a system configuration of this embodiment.

The client machine 1 is connected to an internal or external document storage DB 2 or a similar document storage DB 3 via a network. Client 1 has
It has a text editing application 11 such as a word processor, text editor, mail editor, etc., a file management unit 12 for managing document files, and a file management table 15 for storing file update information based on file names and fonts.

The application 11 has a timer monitoring unit 14 for monitoring the presence or absence of control on the application for a specified time. If there is no control for a fixed time, the application is kept running due to, for example, sudden leaving or loss of the user. In such a state, the application 11 is notified of the state. In response to this notification, the application 11 dynamically activates the font mask processing unit, and replaces the font with the font mask designated as the default after a set period of time.

When performing the editing process again, the user releases the font mask by himself. At this time, the user can be authenticated with a password registered in advance by the password authentication unit 16 in order to record security.

The font mask processing unit 13 refers to a font mask A which has been pre-registered in the font memory 17 and which has been rearranged into an array not corresponding to the character code, or a font mask B which has been converted from a regular font. Then, a process for changing the character designation in the document data is performed. Font change information is managed by the change management unit 18.

FIG. 2 shows the structure of a file management table 15 for managing the presence or absence of a font mask process referred to by the file management unit 12 and the file name. When the font mask processing is performed, a flag is set in the update flag field according to a user's instruction. The update flag is uniquely identified as a group. The OS file management system filters the file name to be displayed by this flag. This filtering can be used to set and release protection for a plurality of files. By replacing the file name displayed on the screen, it can be identified or hidden by the user, using a search engine,
Prevent search by third party by file name. Alternatively, a consistent font mask setting operation using the same flag becomes possible.

FIG. 3 shows the change management table 18 referred to by the font mask processing unit. Here, the correspondence between the original font corresponding to the flag and the font mask applied to the character string, and an arbitrary password used for converting between them are described.

FIG. 4 shows the relationship between the font mask A and the actual document data. In the font processing unit 4, the user embeds the code 41 (B7AA) from the character code table 42 in order to output the character of "chestnut". The font processing unit 4 turns off the font mask processing 43, so that the normal font 44 (for example, Heisei Mincho)
“Chestnut” is output as the regular font 45 from the corresponding character shape of “. On the other hand, the font processing unit 5 similarly embeds the code 51 (B7AA) from the character code table 52. The font processing unit 5 sets the font mask processing 53 to O
Since it is set to N, the corresponding character shape “ta” 56 is output from the illegal font 55 by the font mask A 54 according to the user's specification. This makes it possible to replace the original character string with a meaningless character string, making it impossible for a third party to read it. When using communication, etc., this font mask is stored on a magnetic flexible disk or ROM.
(Read Only Memory) or by means of a protected e-mail or the like beforehand can be used mutually by sharing it with the update partner in advance.

The same applies to the font mask B, except that the font mask A differs from the font mask A.
Refers to a memory in which a character is assigned in a different array as a fixed mask in advance, whereas a font mask B is obtained from a function formula F (X) uniquely obtained by giving a parameter by a user. It changes the font arrangement dynamically. Examples of the function formula F (X) include a means for calculating and converting a displacement offset using the name of a document creator as a key, and a means for replacing an array matrix and a delimiter according to a user's designation.

FIG. 5 is a flowchart showing the processing of the font mask processing section in the present embodiment.

In step S01, a user generates a document or inputs a character string by reediting. Alternatively, a file is selected from the document storage DB2 or the document storage DB3 by the file management system.

In step S02, the user designates the necessity of font mask processing for document data, files, or a plurality of selected files. If font mask processing is requested, a flag is set in step S03. At this time, a password is set in step S04. This password is not essential, but has a function of setting a password so that the font mask is not easily released by a third party.

In step S05, the type of the font mask is specified. If it is the default font mask, step S
At 06, the font is selected from the font memory. If the user wishes to dynamically generate a font mask, the user can perform a font mask generation process for changing the arrangement of the existing selected fonts in step S07 by inputting parameters.
The font mask generated here is stored in step S08.
Is stored in the font memory. In this way, in step S09, the character string is replaced with a font arranged in a different order from the existing font arrangement.

FIG. 6 is a flowchart showing an example of implementing the font mask processing of the present invention.

In step S10, the character code used is detected. In step S11, an existing font used in the application is detected. In an application having no font information, for example, a simple editor, the default font that the OS has as a standard is used.

In step S12, a font mask generation method is designated. In step S13, as a default process, the font corresponding to the character code table is replaced with the upper bit and the lower bit of the character code. JI
In the case of the S kanji code, the kuten is reversed. Step S14 shows the case where the user is designated. By inputting the name in Roman characters, the correspondence between the Roman characters and the reference character code table is analyzed in step S15. Step S1
6. Sum the codes of each alphabetic character composed of 6. Step S1
At 7, an offset value for displacement is calculated. The calculated offset value indicates a distance by which the positional relationship between the character and the font is shifted. In step S18, the font arrangement is changed.

FIG. 7 shows an example of inputting a name in Roman characters and calculating an offset value displaced from a constituent bit string. In the name input section 6, the name is input in Roman characters, and in the name input table 7, the character string is analyzed.
The codes corresponding to the respective characters are totaled, and the calculation result is set in the displacement storage unit 9.

[0026]

As described above, according to the present invention,
By changing the font to a font set with an unintended arrangement, the user's computer can be used for document processing systems that do not have high security requirements, information systems for personal use that do not need to invest in security measures, and portable terminals. This has the effect of reducing the readability of the document content to a third party when the user leaves the desk. Also, in the case of a portable terminal, it is useful as a countermeasure against eavesdropping, loss, theft, etc. on the go.

[Brief description of the drawings]

FIG. 1 is a diagram showing a system configuration according to the present invention.

FIG. 2 is a diagram illustrating an example of a font management table according to the present invention.

FIG. 3 is a diagram illustrating a change management table referred to by a font mask processing unit;

FIG. 4 is a diagram showing an outline of application of a font mask.

FIG. 5 is a flowchart of an embodiment of a font mask processing unit of the present invention.

FIG. 6 is a flowchart illustrating an example of how a font mask processing unit according to the present invention generates a font mask.

FIG. 7 is a diagram illustrating an example of calculating an offset for displacing a font array using a name as a key according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Client part, 11 ... Client application, 12 ... File management part, 13 ... Font mask processing part, 14 ... Timer monitoring part, 15 ... File management table, 16 ... Password authentication part, 17 ... Font memory, 18 ... Change Management unit, 2 ... document storage DB (local), 3 ... document storage DB (network), 4 ... font processing unit, 41 ... character code (code) expression, 42 ... character code table, 43 ... font mask processing, 44 ... regular font to be visualized, 45: visual representation of characters, 5: font processing unit, 51: code (sign) representation of characters, 52 ...
Character code table, 53: font mask processing, 54: font mask, 55: illegal font to be visualized, 56: visual representation of characters, 6: name input section, 7: name input table, 8: offset calculation section, 9: displacement Quantity storage.

Claims (5)

[Claims] In a document processing system in which character encoding and character font information are separated, character encoding and regular font information are performed without using an encryption mechanism such as public key encryption or secret key encryption. By providing a font mask processing unit that changes the association of
A simple document protection device that protects document data from being viewed by a third party and reduces readability. 2. The method according to claim 1, wherein the font mask processing unit changes the regular font from the regular font to an incorrect font after a lapse of a designated time by interlocking with a timer monitoring unit when the control is not given, for example, when the user leaves the terminal. A simplified document protection device characterized by automatic conversion. 3. The simplified document protection device according to claim 1, wherein the font information changed by the font mask processing can be reversibly converted by personal authentication such as a password. 4. The simplified type, wherein the font mask processing unit is applicable to each document file unit, a plurality of file units, a system unit, or each component unit in a document file by being incorporated into an application. Document protection device. 5. The simplified document protection device according to claim 1, wherein said font mask processing unit has a mechanism for displacing a font from encoding information of characters forming a character string using a name as a key.