JP2005202825A - Search system, database system, program and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a search system that resists unauthorized access by having higher flexibility as to a user's rights for searching and browsing. <P>SOLUTION: An input means 131 accepts the input of a decryption key for decrypting a group of documents consisting of a plurality of encrypted email documents registered in a database, the input of search words for searching the group of documents after decryption, and the input of passwords for authenticating the user's right to access the documents. A decryption means 135 decrypts the group of documents using the decryption key when the input is made. A search means 132 conducts searches on the group of documents after decryption. Depending on which of the passwords has been inputted as the password, an output condition selecting means 134 selects the part of the search results to be outputted and presented to the users. An output means 133 outputs the part of the search results selected by the output condition selection means 134, and presents it to the user. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a retrieval system, a database system, a program, and a storage medium for retrieving an encrypted document group.

  Various methods have been devised for maintaining the security of various documents registered in a database or the like.

  For example, documents should have various levels of viewing limits due to business requirements, and in Patent Document 1, it is possible to set the components of a document that can be viewed according to the user's job authority. Yes.

  Patent Document 2 proposes a technique for encrypting a document itself in preparation for an act of browsing the document by unauthorized means.

Japanese Patent Laid-Open No. 06-4530 JP 2001-109668 A

  On the other hand, when a document management system requires a search function to handle a large number of documents, the contents of the document cannot be viewed from a security point of view, but only the author of the document can be presented as the required access destination. Exists. In this case, if you synchronize document viewing authority and document encryption, you will not be able to refer to the contents of the document that should be searched, and you will not be able to search. is there.

  On the other hand, if all the documents can be viewed by the user within the search process, confidential documents that you do not want to hit even in the search will not be seen, but will be found. There is a bug.

  An object of the present invention is to provide a search system that increases the flexibility of search authority and browsing authority of a user and is robust against unauthorized access.

  The present invention provides a decryption key for decrypting a document group consisting of a plurality of encrypted documents, a search term for retrieving the decrypted document group, and access authority information for authenticating a user's access authority to the document. Input means for accepting input, decryption means for executing the decryption with the decryption key when the input is received, search means for executing the search, and contents to be output and presented to the user among the search results Output condition selection means for selecting the information according to the access authority information, and output means for outputting the selected contents of the search results and presenting them to the user.

  Another aspect of the present invention relates to a decryption key for decrypting a document group composed of a plurality of documents encrypted with an encryption key, a search term for retrieving the decrypted document group, and a user's document An input unit that receives an input of access authority information for authenticating an access authority; a decryption unit that executes the decryption with the decryption key when the input is received; a search unit that executes the search; and a result of the search Output condition selection means for selecting the content to be output and presented to the user according to the access authority information; and output means for outputting the selected content of the search results and presenting to the user. A computer-readable program that is executed by a computer.

  According to the present invention, since a user who cannot present a decryption key cannot search a document group, security can be protected. On the other hand, even when a decryption key can be presented and a search is executed, depending on the access authority information presented by the user, only a specific part of the search result, such as the document ID or title, can be browsed. Therefore, it is possible to increase the flexibility of the search authority and browsing authority of the user and provide a robust search system against unauthorized access.

  The best mode for carrying out the present invention will be described.

  FIG. 1 is an explanatory diagram showing an external configuration of the database system 101 according to the present embodiment. The database system 101 implements the database system of the present invention, and constructs, for example, a database for storing e-mail data in a computer terminal 102 composed of a computer terminal such as a PC. A database (DB) device 103 is connected. Further, the computer terminal 102 is connected to an SMTP server 105 in the office or the like via a LAN 104, and an electronic mail transmitted from the SMTP server 105 can be transmitted to the computer terminal 102 as a log.

  The DB device 103 stores all e-mails transmitted by the SMTP server 105. In addition to the title and text, the stored e-mail is appended with an ID that is uniquely assigned to the e-mail on the DB device 103, and is encrypted with an encryption key.

  FIG. 2 is a block diagram showing electrical connection of the computer terminal 102. The computer terminal 102 implements the search system of the present invention. As shown in FIG. 1, the computer terminal 102 performs various calculations and centrally controls each part of the profile system 1, and a memory composed of various ROMs and RAMs. 112 is connected by a bus 113.

  A bus 113 includes a magnetic storage device 114 such as a hard disk, an input device 115 such as a keyboard and a mouse, a display device 116, and a storage medium reader 118 that reads a storage medium 117 such as an optical disk via a predetermined interface. And a predetermined communication interface 119 for communicating with the network 121 such as the Internet and the LAN 104 and the SMTP server 105 is connected. As the storage medium 117, various media such as an optical disk such as a CD and a DVD, a magneto-optical disk, and a flexible disk can be used. As the storage medium reader 118, specifically, an optical disk device, a magneto-optical disk device, a flexible disk device, or the like is used according to the type of the storage medium 117.

  The computer terminal 102 reads the program 120 for executing the program of the present invention from the storage medium 117 for implementing the storage medium of the present invention and installs it in the magnetic storage device 114, thereby enabling a predetermined operation described later. . These programs may be downloaded and installed via the network 121 such as the Internet. The program 120 may operate on a predetermined OS.

  Next, processing executed by the computer terminal 102 using the program 20 will be described.

  First, data registration processing in the DB device 103 will be described. Such processing is processing based on the database registration program included in the program 20. First, a registration screen 201 as shown in FIG. 3 is displayed on the screen of the computer terminal 102. On this screen 201, a registration password input box 202 for inputting a password as an encryption key, a list 203 of registration e-mails transmitted from the SMTP server 105 in advance, and a registration execution button 204 are displayed.

  When the user inputs the registration password “1111” in the registration password input box 202 and presses the button 204, the e-mail data displayed in the list 203 is encrypted by a known means with an encryption key. The encrypted electronic mail data is registered in the DB device 103. The input password “1111” can be decrypted with the decryption key “2222”. Further, the DB device 103 uniquely assigns and registers a mail ID to the encrypted electronic mail.

  Next, registration data search processing of the DB device 103 will be described. Such processing is processing based on a search program included in the program 20.

  FIG. 4 is a functional block diagram of processing based on the search program. That is, FIG. 4 implements the search system according to the present invention. Based on the search program, decryption given to a document group consisting of a plurality of documents (e-mails) registered in the DB device 103 is performed. Decryption means 135 for decrypting the document group by means known by a key, input means 131 for accepting input of search words and other information necessary for the search from the user, and execution of search for the above-described decrypted document group According to whether or not there is an input of an ID browsing password, a title browsing password, and a text browsing password as an access key to be described later. The user's access authority to the e-mail document is authenticated, and the output by the output means 133 depends on which of these passwords is input. To achieve an output condition selection unit 134 for selecting.

  The input unit 131 will be described. In this process, a search screen 211 as shown in FIG. 5 is displayed on the screen of the computer terminal 102. The search screen 211 implements the input means 131, and includes a search word input box 212, a search ID input box 213, a search password input box 214, an ID browsing password input box 215, a title browsing password input box 216, A text browsing password input box 217 and a search execution button 218 are displayed.

  A search word is input into the search word input box 212. This search term is used to search e-mail data, and the search target is the title and text of the e-mail. In the search ID input box 213, in order to search for a mail ID uniquely assigned by the DB apparatus 103, the mail ID is input. A search password is entered in the search password input box 214. This search password is a decryption key at the time of search, and it is possible to decrypt e-mail data encrypted with the encryption key. The ID browsing password input box 215 is a column for inputting a search password as an access key. The title browsing password input box 216 is a column for inputting a password for a title viewer as an access key. The text browsing password input box 217 is a field for inputting a text browsing password as an access key.

  As described above, predetermined items are input to the search screen 211, and at the time of search, the e-mail data in the DB device 103 is decrypted by the decryption key, and the search unit 132 performs a search by a known unit. The search result is passed to the output condition selection means 134, and the search result is narrowed down according to whether or not an ID browsing password, a title browsing password, and a text browsing password as an access key are input (described later).

  The output condition selection unit 134 will be described in detail. FIG. 6 is a flowchart of processing executed by the output condition selection unit 134. In this process, it is determined whether or not each of an ID browsing password, a title browsing password, and a text browsing password as an access key has been input (steps S1 to S3). First, when an ID browsing password is input as an access key (Y in step S1), only the mail ID among the results searched by the search means 132 is narrowed down as the result output contents by the output means 133 (step S4). ). When the ID browsing password and the title browsing password are input as the access key (Y in step S2), only the mail ID and the mail title among the results searched by the search unit 132 are the results by the output unit 133. The contents of the output are narrowed down (step S5). When an ID browsing password, a title browsing password, and a text browsing password are input as an access key (Y in step S3), the mail ID, the mail title, and the mail The text is narrowed down as the contents of the result output by the output means 133 (step S6). When none of these access keys is input (N in step S3), a predetermined error process is performed (step S7), and the series of processes is terminated.

  In the following, the results obtained by the processing executed by the output condition selection means 134 will be specifically described.

  On the search screen 211 shown in FIG. 5, for example, the user inputs “patent search”, which is an in-house technical term, into the search word input box 212, and the search password serving as a decryption key in the search password input box 214. “2222”, an ID browsing password “3333” serving as an access key is entered in the ID browsing password input box 215, and a search execution button 218 is pressed to instruct execution of the search (see FIG. 7). Only the user knows the ID browsing password.

  As a result, the encrypted electronic mail registered in the DB device 103 is decrypted by the search password “2222” serving as a decryption key, and the search unit 132 executes the search. The search result is transferred to the output condition selection means 134, and the search result is narrowed down to only the mail ID by the ID browsing password “3333” as an access key. Then, the output unit 133 displays the search result screen 221 shown in FIG. 8, and the mail ID “13, 34, 103, 302, 913, 948” is displayed in the searched mail ID display field 222. At this time, the title and text of the e-mail are not displayed.

  Next, a user who has the authority to view the title of the e-mail uses the search ID input box 213 to search for the mail ID obtained by the previous searcher in the search screen 211 of FIG. The search password “2222”, which is a decryption key, and the title viewer password “4444”, which is an access key, are input to the title browsing password input box 216, and a search is executed by pressing the search button 218 ( (See FIG. 9). Only the user having the title viewing authority knows the title viewing password.

  In this example, a search result screen 221 as shown in FIG. 10 is displayed as a search result, the mail ID is displayed in the mail ID display field 222, and the e-mail title is displayed in the title display field 223. At this time, the text of the mail is not displayed.

  Thereby, since the person who has the authority of title browsing can browse a title, it can guess the content of the text of an email. At this time, the person who has the authority of the title removes the e-mail that is not related to the in-house technology from the subject of browsing the text, for example, selects the e-mail that is subject to the text browsing as “103, 302, 948” can do.

  Next, a user who has the authority to view the text of the e-mail enters the search ID input box 213 in the search screen 211 of FIG. "In the search ID input box 213, the search password" 2222 "as a decryption key in the search password input box 214, and the text browsing password" 5555 "as an access key in the text browsing password input box, respectively. Input is performed and the search execution button 218 is pressed (see FIG. 11) to execute the search. Only the user who has the authority to view the text of the e-mail knows the text browsing password.

  As a search result in this case, a search result screen 221 is displayed as shown in FIG. 12, the mail ID and title of the e-mail are displayed as described above, and the text is displayed in the text display field 224. Here, the user who has the authority to view the text of the e-mail can check whether or not the information about the in-house technology is written.

  According to the database system 101 described above, a user who cannot present a search password that is a decryption key cannot search for a group of e-mail documents in the DB device 103, so that security can be protected. On the other hand, even if a search password that is a decryption key can be presented and a search is executed, any one of ID viewing password, title viewing password, and text viewing password that is access authority information presented by the user is presented. As a result, only a specific part of the search result such as the mail ID or title of the e-mail document can be browsed. It is possible to provide a robust search system for access.

  In the above example, the access authority information is a password, that is, an access key ID browsing password, title browsing password, and text browsing password are entered by the user to authenticate the user's access authority to the email document. However, the present invention is not limited to this, and various information can be used as the access authority information. For example, a user's fingerprint may be authenticated as access authority information using a known fingerprint authentication system. In this case, the fingerprint image of each user and the access authority (whether only the mail ID can be viewed, the title can be viewed, or the body can be viewed) are associated with each other and registered in a predetermined table. When the user's fingerprint is input, the access authority for the user's electronic mail document may be determined by referring to this table.

  Even when a password is used as described above, in the above example, the user's access authority to the e-mail document is authenticated by three types of passwords: an ID browsing password, a title browsing password, and a text browsing password. However, this may be a single password. However, even with a single password, the password to be used is changed depending on the access authority of the user. In this case, the password and the access authority of the user (whether only the mail ID can be viewed, the title can be viewed, or the body can also be viewed) are associated and registered in a predetermined table, and the user's fingerprint Is entered, the user's access authority may be determined by referring to this table.

It is an external view which shows the whole structure of the database system of this Embodiment. It is a block diagram of the electrical connection of the computer terminal which comprises a database system. It is a front view of the screen for registration. It is a functional block diagram of a search system. It is a front view of the screen for search. It is a flowchart of the process which an output condition selection means performs. It is a front view of the screen for a search when inputting the password for ID browsing as an access key. It is a front view of the search result screen which displayed the search result in the case of FIG. It is a front view of the screen for a search in the case of inputting the password for ID browsing, and the password for title browsing as an access key. FIG. 10 is a front view of a search result screen displaying search results in the case of FIG. 9. It is a front view of the screen for a search in the case of inputting the password for ID browsing, the password for title browsing, and the password for text browsing as an access key. It is a front view of the search result screen which displayed the search result in the case of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Database system 103 Database 117 Storage medium 120 Program 135 Decoding means 131 Input means 132 Search means 133 Output means 134 Output condition selection means

Claims (8)

Input for receiving input of a decryption key for decrypting a document group composed of a plurality of encrypted documents, a search term for retrieving the decrypted document group, and access authority information for authenticating the user's access authority to the document Means,
Decryption means for performing the decryption with the decryption key when the input is received;
Search means for performing the search;
Output condition selection means for selecting the content to be output and presented to the user among the search results according to the access authority information;
An output means for outputting the selected content of the search results and presenting it to the user;
Search system equipped with. The input means accepts an input of a password as the access authority information,
The output condition selection means performs the selection according to the input password.
The search system according to claim 1.   The output condition selection means includes the ID, the ID and the title, or the ID assigned to each document, the title of each document, and the text of each document according to the access authority information. The search system according to claim 1 or 2, wherein any one of the ID, the title, and the text is selected as content to be presented to the user. The search system according to any one of claims 1 to 3,
A database in which a document group consisting of a plurality of encrypted documents to be the document group is registered;
A database system equipped with. Input of a decryption key for decrypting a document group composed of a plurality of documents encrypted with an encryption key, a search word for retrieving the decrypted document group, and access authority information for authenticating the user's access authority to the document Input means for accepting,
Decryption means for performing the decryption with the decryption key when the input is received;
Search means for performing the search;
Output condition selection means for selecting the content to be output and presented to the user among the search results according to the access authority information;
An output means for outputting the selected content of the search results and presenting it to the user;
A computer-readable program that causes a computer to execute. The input means accepts an input of a password as the access authority information,
The output condition selection means performs the selection according to the input password.
The program according to claim 5.   The output condition selection means includes the ID, the ID and the title, or the ID assigned to each document, the title of each document, and the text of each document according to the access authority information. The program according to claim 5 or 6, wherein any one of the ID, the title, and the text is selected as content to be presented to the user. The storage medium which has memorize | stored the program as described in any one of Claims 5-7.

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