JP2007241907A - File encrypting system comprising positional information, decrypting system, and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for encrypting and decrypting a file comprising positional information, preventing access if the file is carried out from a high security area and specifying the physical position of the carried out file by setting up regions permitted to access the file in the file itself. <P>SOLUTION: A GPS function is provided to a terminal unit; the regions which can be used for each file are set up, and software preventing opening of the file except for the set up region is loaded on a terminal. When opening the file, the terminal checks whether or not it is in the designated regions. The positional information of the terminal and the information of the file are stored in the terminal unit and are transmitted to a server at arbitrary timing. By retrieving such information, the operation history of the file can be grasped. Since the place which can be decrypted is set up for each file, a file which can be read only in the physically high security area can be created. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a file encryption / decryption technique with position information for a folder or file of a fixed or mobile terminal device.

  With the miniaturization and large capacity of terminal devices and the advancement of network technology, files can be easily copied and moved. For example, store a file in a portable storage medium that can be attached to and detached from the terminal body, carry it at home, or download the latest file using a network line, etc. Various applications are becoming possible.

  On the other hand, in recent years, serious damage caused by taking out confidential data or leaking customer data due to theft has not been complete. Various proposals have been made for access management of such confidential data. For example, a terminal that can access confidential data is specified in advance, and the terminal is placed in a physical high-security area that requires biometric authentication, etc. There is a method to do.

In addition, as shown in Patent Document 1 below, in order to prevent remote access from unauthorized terminals, the location information of the terminal device obtained using GPS (Global Positioning System) and the registered information stored in the server There is a method of authenticating the physical location of the terminal device by comparing the location information of the terminal device and permitting network access.
JP2001-306530

  By the way, even if it is a file with a detailed access right set in a specific terminal device in a high security area using biometric authentication, an unspecified number of users can be taken out of the file once taken out. Can be accessed, and data leakage occurs. For this reason, by managing the access history for files, the morals of people entering the high security area may be improved, or operations may be carried out to prevent taking out by multiple people when entering the high security area. ing. However, in spite of this, there are cases in which customer data is taken out by people who can enter the high security area and criminal cases occur.

  In the technique described in Patent Document 1, access control is performed for each terminal device, and access control for each file or folder cannot be performed.

  An object of the present invention is to set an area in which a file can be accessed in the file itself, so that even if the file is taken out from the high security area, the file cannot be accessed, and the physicality of the taken out file is further reduced. An object of the present invention is to provide a technique for encrypting and decrypting a file with position information so that the physical position of the file can be specified by transmitting a specific location to the server.

  In order to achieve the above object, the present invention encrypts a file data body with a predetermined file encryption key, and adds file decryption permission position data indicating an area where the file is permitted to be decrypted to the encrypted file data body. The encrypted file data body to which the file decryption permission position data is added is encrypted with a predetermined encryption key to create an encrypted file with position information.

  Further, the present invention obtains a decryption key corresponding to the encryption key when decrypting such an encrypted file with position information, and uses the obtained decryption key to store the encrypted file with position information. Decrypts, acquires the file decryption permission position data and the encrypted file data body, obtains the current position of the own system, and the current position is in an area that permits decryption of the file indicated by the file decryption permission position data. A file decryption key for decrypting the encrypted file data body is obtained only when the current position is included in the region where decryption is permitted, and the file decryption key is obtained. The encrypted file data main body is decrypted by using.

  Further, the present invention is a system in which a server and a terminal device are connected to a network, and an encryption key acquisition request is transmitted from the terminal device to the server, and in response to the encryption key acquisition request, the server An encryption key is transmitted, and the server stores the encryption key in association with the terminal device. The terminal device receives the encryption key transmitted from the server, and the terminal device The file decryption permitted position data indicating the area where decryption is permitted is input, and a file encryption key is generated from the encryption key acquired from the server and the file decryption permitted position data, and the unencrypted file data body is stored. The file is encrypted with the file encryption key, and file decryption permission position data indicating an area where the decryption of the file is permitted is added to the encrypted file data body, and the file Decoding permission position encrypted file data body data is added, the encrypted encryption key acquired from the server, and wherein the creating location information with encrypted files.

  In the present invention, when decrypting the encrypted file with position information, the terminal device transmits a decryption key acquisition request to the server, and the server responds to the decryption key acquisition request by the server. A decryption key corresponding to the encryption key is transmitted, the decryption key transmitted from the server is received by the terminal device, and the terminal device encrypts the encrypted file with the location information using the decryption key. Decrypting, obtaining the file decryption-permitted position data and the encrypted file data body, obtaining the current position of the terminal device, and the current position is an area where the decryption of the file indicated by the file decryption-permitted position data is permitted Only when the current position is included in the region where the decryption is permitted, only from the decryption key obtained from the server and the file decryption permitted position data, It generates a file decryption key for decrypting the serial encrypted file data body portion, using the generated file decryption key, wherein the decrypting the encrypted file data itself.

  Further, the terminal device transmits an operation history performed on the encrypted file with position information and the current position of the terminal device when the operation is performed to the server, The operation history transmitted from the terminal device and the current position of the terminal device may be stored in a file position information history database.

The present invention has the following effects.
(1) A file that can be used only in a high security area can be created.
(2) The location of the file taken out can be specified using map data or the like.
(3) The location of the file can be specified even when the file name of the file taken out is changed.
(4) The position history of the file taken out can be checked.
(5) The location can be specified even when the file taken out is copied.
(6) A place where the terminal device can be used can be specified.
(7) The file can be used in two ways: a method set on the server side and a method set on the user side. Can be specified by address, building, etc.
(8) A map used within the usable range of the file can be received from the host system at any time.
(9) Since the host system holds the contract information of the server, the latest map request from a party other than the contractor can be eliminated.

  Hereinafter, an embodiment of a file encryption system with position information to which the present invention is applied will be described.

  FIG. 1 is a system configuration diagram showing an embodiment of the present invention. The encryption system with position information of this embodiment includes a host system 101 having a map database 107, a plurality of servers 102a, 102b,..., And 102n that receive map data from the host system 101, and the positions of terminal devices. A plurality of client terminal devices 103a, 103b,..., And 103n including a GPS (Global Positioning System) unit 104 for acquiring information are provided. The number of servers 102a, 102b,..., And 102n is arbitrary. When referring to an arbitrary server, it is referred to as “server 102”. The number of terminal devices 103a, 103b,..., And 103n is also arbitrary. When referring to any one terminal device, it is called “terminal device 103”.

  In addition to the map database 107, the host system 101 in FIG. 1 is connected to an updated partial map database 108 that stores an updated portion of map data, and a server information database 109 that stores server information of a location information encryption contractor. Has been. In the map database 107 of the host system 101, for example, map data including a map ID, a map, a region name, a building name, a latitude, and a longitude are registered. In the updated partial map database 108 of the host system 101, the update date and time and the update region of the map database 107 are registered. The updated partial map database 108 is updated at the same timing as the update of the map database 107. In the server information database 109, contract information of the location information encryption contractor is registered. The contract information of the location information encryption contractor includes the contractor information, the server information, the number of connectable terminal devices, the contract period, and the like. These information are used when a map is transmitted to the server 102. used.

  The host system 101 includes a database update unit 110 that performs update processing of the map database 107 and the updated partial map database 108, a transmission / reception unit 111 that mainly processes update requests for map data sent from the server 102, a server A server confirmation unit 112 is provided for registering a location information encryption contractor in the information database 109 and confirming whether or not the server making a map data update request is the contractor.

  The server 102a includes a map database 113 that stores the map data distributed from the host system 101 and the latest update date, a file location information history database 114 that stores the location information history of the file of the terminal device 103, and a file in units of files. A file decoding permission position database 115 for storing the decoding permission position (area) and a terminal database 116 for managing the number of contracted terminals and storing terminal information for transmitting map data are connected.

  In the map database 113, the map data received from the host system 101 and the update date of the map data are registered. At the time interval set in the server 102a (the time interval can be arbitrarily set by the user), the server 102a connects to the host system 101, receives the updated map data from the previously acquired map, The map database 113 is periodically updated.

  In the file position information history database 114, position information histories of encrypted file data with position information of a plurality of terminal devices 103a, 103b,..., 103n are registered. The data stored in the file location information history database 114 includes the location information of the longitude and latitude of a file to be managed by this system, time, and the like. These data are transmitted from the terminal device 103 to the server 102a at a specific timing and stored in the file position information history database 114. Therefore, by referring to the file position information history database 114, it is possible to refer to which file was present when and where.

  In the file decryption permission position database 115, positions (regions) where decryption of encrypted file data with position information created by the plurality of terminal devices 103a, 103b,. The file decryption permission position data is data for the server administrator to designate a specific file and set the file decryption permission position. For example, when the file decryption permission position is set for the system file of the terminal device 103a, the system file of the terminal device 103a is encrypted, so that it is possible to set an area where the terminal device 103a can be used. .

  In the terminal database 116, unique information of a plurality of terminal devices 103a, 103b,..., 103n is registered, and only for the contracted number of terminal devices (terminal devices managed by the server 102a). An encryption service with location information can be provided.

  Further, the server 102a acquires the map data from the map database 113, inputs the map display unit 117 for displaying the acquired map data, and the file decoding permission position data, and the file decoding permission position in the file decoding permission position database 115. A file decoding permission position data input unit 118 for storing data, a position (region) where file decoding is permitted is acquired from the file decoding permission position database 115 and the terminal database 116, and decryption permission position data transmission is transmitted to the terminal device 103. Unit 119, file position information receiving unit 121 for receiving file position information history data from a plurality of terminal devices 103a, 103b,..., And 103n, map database 113, file position information history database 114, file decoding permission position database 115 and the search processing unit 122 for searching the contents of the terminal database 116, and the search A search result display unit 120 for displaying the results, a position information history display processing unit 123 for reading and displaying the history of the file position information from the file position information history database 114, and an encryption key and a decryption key for the terminal device 103. And an issuing certificate authority 124. The other servers 102b to 102n having an arbitrary number have the same configuration.

  The terminal device 103a in FIG. 1 acquires a plurality of location information-encrypted files 125 encrypted with the encryption key and location information transmitted from the certificate authority 124 of the server 102, and the location information of the terminal device 103a. Therefore, a GPS (Global Positioning System) unit 104 that receives radio waves from a satellite and detects the current position of the device itself is provided. The file 125 in the terminal device 103a is encrypted using an encryption key issued by the certificate authority 124 of the server 102 so that it can be decrypted and used only in a specific region. The file 125 can be encrypted by a command from the user of the terminal device 103a or by a command from the administrator of the server 102. The other terminal devices 103b to 103n having an arbitrary number have the same configuration.

  1 is connected to a plurality of servers 102a, 102b,..., And 102n contracted with the host system 101 for location information encryption so that the map information on the server 102 can be updated as necessary. It is configured. Terminal devices 103a, 103b,..., And 103n within the number of connectable terminal devices contracted with the server 102 are connected to the network 106, and the history of location information encrypted files in the terminal can be transmitted to the server 102. The map data on 102, the file decryption permission position, the encryption key or the decryption key issued from the certificate authority can be transmitted to the terminal device 103.

  FIG. 2 is a detailed configuration diagram of the terminal device 103 of FIG. The terminal device 201 includes a map database 202 for storing map data sent from the server 102, a file location information history database 203 for storing an access history of a file encrypted by location information in the terminal device, Using the GPS unit 204 for receiving the radio wave from the satellite to detect the current position of the own device and the encryption key issued by the certification authority 124 of the server 102, the position information in the terminal device And an encrypted file 205.

  Further, the terminal device 201 includes a map display unit 206 for visualizing the map data stored in the map database 202, a position information acquisition unit 207 for acquiring the current position of the terminal device from the GPS unit 204, and position information. A file processing unit 208 including an encryption unit 209 for encrypting a file and a decryption unit 210 for decrypting the file, and a location information history transmission for transmitting the location information history of the file to the server 102 A unit 211 and an input unit 212 for inputting a file decryption permission position and the like.

  In the map database 202 of FIG. 2, the map data received from the server 102 of FIG. 1 and the update date of the map data are registered. At a time interval set in the terminal device 201 or the server 102, the terminal device 201 connects to the server 102, receives an updated portion of the map, and periodically updates the map database 202.

  FIG. 3 is a data table of map data and map related information stored in the updated partial map database 108 of the host system 101 of FIG. The updated partial map database 108 has fields of area ID 301, representative place name 302, start point latitude 303, start point longitude 304, end point latitude 305, end point longitude 306, registration / update date and time 307, and section 308. In the database 108, information of each field is registered for each registration or update date.

  For example, when the map surrounded by the rectangles of “35.19.40 east longitude, 139.25.00 north latitude” and “35.19.50 north latitude 139.25.05” in the map database 107 of the host system 101 is updated as shown in FIG. As shown in the figure, the district ID is `` 0010030031122333398 '', the representative place name is `` Chigasaki-Kagasaki City, East Coast North 5-chome '', the start longitude is `` East 35.19.40 '', the start latitude is `` North latitude 139.25.00 '', and the end longitude is `` East longitude '' "35.19.50", the latitude of the end point is "139.25.05", the registration / update date and time is "August 31, 2005 00:00:00", and the category "Map" is registered in the updated partial map database 108 The

  In addition to the data format that specifies the latitude and longitude of the start and end points of a rectangular area, the polygon area can be specified by arranging multiple latitudes and longitudes, as described above. The data format may be as follows.

  FIG. 4 shows a configuration example of the district ID 301. The district ID 301 includes country ID 401, area ID 402, prefecture ID 403, municipality ID 404, and place name ID 405. For example, in the case of “Chigasaki Kita-chome North 5-chome, Kanagawa Prefecture”, the code ID “001” for “Japan” as the country, the code ID “003” for “Kanto” as the region, “0010030031122333398” becomes the district ID 301 as a combination of the code ID “11223” of “Chigasaki City” as the municipality and the code ID “33398” of “East Coast North 5-chome” as the place name. When such an area ID is designated in an area where file decryption is permitted, the location where decryption is permitted is designated by storing the area ID in the file.

  FIG. 5 shows a configuration example of the contract information of the location information encryption contractor stored in the server information database 109 of the host system 101. The contract information of the location information encryption contractor is composed of contractor ID 501, contractor name 502, representative contractor address 503, contract form 504, contract date 505, product key 506, and number of connected terminals 507. Unique ID for each subscriber, contractor name or corporate name, representative contractor address, contract form, contract period for sending map data and map related information, product key for uniquely specifying the server, and connection to the server The number of terminal devices to be registered is registered.

  The contract form 504 indicates a contract form based on a server configuration method. For example, this contract form can be configured with a fault-tolerant server that provides a single service with multiple servers to improve server performance or cope with server failures, or with a single server. Used to support the client server configuration, such as the configuration of the server provided.

  FIG. 6 shows an example of the configuration of file position information history information stored in the file position information history database 114 of the server 102 of FIG. The file position information history is composed of a file identifier 601, a date 602, a longitude 603, a latitude 604, a file name 605, a user operation 606, and a user name 607, each of which identifies a unique file in all systems. Identifier, the date and time when data was sent from the terminal device, the latitude of the terminal device, the longitude of the terminal device, the file name with extension, and the user's operation that triggered this file location information history data , And a user name are registered.

  This file location information history is transmitted from the terminal device 103 to the server 102 and stored in the file location information history database 114 when any user operation is performed on the encrypted file with location information in the terminal device 103. . User operations that trigger sending of file location information history data from the terminal device 103 to the server 102 include “read data”, “write data”, “delete file”, “change file name”, And operations such as “file copy”. Further, this user operation includes “periodic transmission” (not strictly a user operation) and “when network connection starts”. “Periodical transmission” refers to a case in which the file information about the encrypted file with all position information of the terminal device 103 is sent to the server 103 periodically (the period can be set by the user). “At the start of network connection” refers to the case where the file information about the encrypted file with all position information is sent to the server 103 when the terminal device 103 starts to connect to the network 106. When these user operations are performed, the terminal device 103 transmits the file position information history data described in FIG. 6 (the user operation 606 describes the user operation that has been triggered) to the server 102. The server 102 stores the received file position information history data in the file position information history database 114.

  The file identifier 601 is created using each data of “MAC address”, “system time”, and “file name” of the terminal device. When an encrypted file with location information is copied, a file location information history corresponding to the encrypted file with location information at the copy destination is created, but the “copy destination file identifier” is “copy source file identifier”. The “copy destination file identifier” can be found by looking at the “copy destination file identifier”. Therefore, even when the file is copied, the location of the copy source file can be specified. Since the “MAC address” is unique for each terminal and the “system time” also changes every moment, the same file identifier does not exist throughout all systems.

  The file identifier 601 is not changed when the file name is changed. For example, even if the name of an encrypted file with location information whose file name 605 is “location information encryption basic design document.txt” is changed to “20050804_location information encryption basic design document.txt”, the same File identifier.

  FIG. 7 shows a configuration example of file decryption permission position data stored in the file decryption permission position database 115 of the server 102. The file decryption permission position data is composed of a file identifier 701, a file path 702, region data 703, and an encryption flag 704, respectively, an identifier for specifying a file, a path of a file to be encrypted by position information, and a file The area where the decryption of the file is permitted and the flag information indicating whether or not the file is encrypted are registered.

  The file identifier 701 accesses the terminal database 116 when the path of the file to be encrypted by the location information is set, and the “MAC address”, “system time”, “file name”, etc. of the corresponding terminal device Generate using.

  The file decryption permission position database 115 is used when the administrator of the server 102 or the user of the terminal device 103 designates a specific file and sets the position access right. For example, it is possible to set a region where the terminal device 103a can be used by setting an access right that can be decrypted only in a specific region with respect to the system file of the terminal device 103a.

  When the administrator of the server 102 designates a specific file of the terminal device 103 and sets and encrypts the file decryption permission position data, first, the administrator of the server 102 uses the server 102 and the terminal device 103 to It specifies which file of the terminal device 103 is to be encrypted. Thereby, the file decryption permission position data of the specified file is set in the file decryption permission position database 115. The area data 703 indicating the area where decryption is permitted is set by the administrator using a method described later with reference to FIG. At this time, the encryption flag 704 is “not encrypted”. Thereafter, when the server 102 and the terminal device 103 can communicate with each other at an appropriate timing, the server 102 transmits an encryption command for the file to the terminal device 103. When the terminal device 103 receives the encryption command, the terminal device 103 performs the processing shown in FIG. 12 described later (however, since the administrator has already specified the region where the file is permitted to be decrypted, the region is determined in step 1203. The position information shown is used), and the file is encrypted to be an encrypted file with position information. When the encryption process is finished, the terminal device 103 notifies the server 102 to that effect. Upon receiving the notification, the server 102 sets the encryption flag 704 of the file decryption permission position data relating to the file to “encrypted”.

  Further, when the user of the terminal device 103 himself designates and encrypts a file in the own device, the user first designates which file is to be encrypted in the terminal device 103. When this designation is made, the processing of FIG. 12 described later is executed, and the file is made an encrypted file with position information. Thereafter, the terminal device 103 notifies the server 102 of the file identifier of the encrypted file, the file path, and the area data indicating the area where decryption is permitted. Upon receiving the notification, the server 102 registers the file decryption permission position data regarding the file in the file decryption permission position database 115. At this time, the encryption flag 704 is “encrypted”.

  FIG. 8 shows a configuration example of information on terminal devices stored in the terminal database 116 of the server 102. The terminal device information is composed of a terminal device identifier 801, a terminal name 802, and a MAC address 803, and a terminal device identifier value, a terminal name, and a MAC address stored in the terminal device issued by the server are registered. Is done.

  The value of the terminal device identifier 801 is a value issued from the server 102 to the terminal device 103 when the software related to the location information encryption system is installed in the terminal device 103, and the server is the timing when the installation is completed. It is stored in the terminal database 116 of 102.

  When the value of the map database 202 of the terminal device 103 is updated, the terminal device information in the terminal database 116 is compared with the terminal information, and the map data is transmitted.

  Hereinafter, the operation of the positional information encryption system configured as described above will be described.

  FIG. 9 is a flowchart showing an overview of server information addition processing in the host system 101. This process is executed when a new server 102 is added (that is, when a new location information encryption contractor is registered).

  First, a new record is added to the server information database 109 (FIG. 5) of the host system 101, and the “contractor ID”, “contractor name”, “representative contractor address”, “contract” of the contractor are added to the record. The “type”, “contract date”, and “number of connected terminals” are registered (step 901). The information entered in the host system 101 may be registered as this information, but the contractor has previously contracted and the "contractor name" and "representative contractor address" are known. May use such information. When registration in the server information database 109 is completed, the host system 101 generates and pays out a “product key” according to the registered information (step 902). The issued “product key” is registered in the record of the server information database 109 and sent to the server 102 via the network 105. The server 102 installs the file encryption system with location information using the product key issued by the host system 101 (step 903). The server 102 transmits the product key to the host system 101 after the installation of the file encryption system with position information is completed.

  The host system 101 uses the server confirmation unit 112 to compare the product key information transmitted from the server 102 with the product key registered in the server information database 109. If they match, it means that the server has been added appropriately, and the map data in the map database 107 is transmitted to the server 102 by the transmission / reception unit 111 according to the contract form. The server 102 receives the map data and registers the map data and the data update date in the map database 113 (step 904). This completes the server information addition process.

  FIG. 10 is a flowchart illustrating an outline of the terminal device addition process. This process is started by connecting to the server 102 from the terminal device 103 to be added, obtaining a program for installing the file encryption system with position information, and executing it on the terminal device 103.

  The program for installing the file encryption system with position information first transmits the MAC address and terminal device name of the terminal device 103 to the server 102 via the network 106 (step 1001). The server 102 compares the received MAC address of the terminal device with the MAC address data already registered in the terminal database 116 (FIG. 8). If the same MAC address exists, the file encryption system with location information is already installed. If it is determined that the installation has not been completed, it is determined that the installation has not been performed (step 1002).

  If the installation has not been performed, since it is a new terminal, it is determined whether the number of terminal devices registered in the terminal database 116 is equal to or greater than the number of connected terminals permitted for the server by contract (step 1003). If the number of terminal devices registered in the terminal database 116 is equal to or greater than the number of contracted terminals, it is determined that the file encryption system with position information has already been installed for the number of contracted terminals. No new addition is allowed, and the installation is terminated as a failure (step 1005). If the number of terminal devices registered in the terminal database 116 is not equal to or greater than the number of contracted terminals, the server 102 generates a terminal device identifier and adds the terminal device information of the terminal to the terminal database 116 (FIG. 8) ( Step 1004). After step 1004 or if the terminal has installed the file encryption system with location information in step 1002, the server 102 sends the program and map data of the file encryption system with location information to the terminal 103, A file encryption system with location information (terminal version) is installed in the terminal 103 (step 1006). In addition, when proceeding from step 1002 to step 1006, re-installation is performed.

  FIG. 11 is a flowchart showing map data update processing on the map database 113 of the server 102. First, the system date (current time) is compared with the latest update date of the map database 113 of the server 102, and it is determined whether the update period of the map set in advance in the server 102 has elapsed (step 1101). If the update period of the map set in advance in the server 102 has elapsed, the server 102 connects to the host system 101, and the product key (the one assigned to the server 102 in step 902 in FIG. 9) Send. In the host system 101, the server confirmation unit 112 determines whether the contract period of the server 102 stored in the server information database 109 (FIG. 5) has expired (step 1102).

  If the contract period has not expired, the latest map database update date of the server 102 is transmitted to the host system 101, and the updated partial map database 108 (FIG. 3) of the host system 101 is updated with the latest map database update date of the server 102. Whether there is new map data is also determined (step 1103). When there is map data that is newer than the latest map database update date of the server 102 in the updated partial map database 108 of the host system 101, the latest map data is acquired from the host system 101 and the map database 113 of the server 102 is updated ( Step 1104).

  When the server has a fault tolerance configuration, one main server can be connected to the host system, and other servers can be connected to the main server to update the map data.

  FIG. 12 is a flowchart showing file encryption processing executed by the encryption processing unit 209 of the terminal device 201 (103 in FIG. 1). First, the terminal device 103 determines whether a valid file encryption key has been acquired from the server 102 (step 1201). If the terminal device 103 has not acquired a valid encryption key from the server 102, the terminal device 103 connects to the server 102 and acquires an encryption key that has not expired (step 1202). A user who encrypts a file using the terminal device 103 uses the map display unit 206 of the terminal device to designate an area where decryption of the file to be encrypted is permitted (step 1202).

  FIG. 13 shows an example of a method for designating an area where file decryption is permitted in step 1202. As a specification method, a map of a predetermined region is displayed using the map display unit 206, and a latitude and longitude of a region in which the user is permitted to decode a file on the map interactively, There is a method of designating an area stored in the map database 202.

  In 1301 of FIG. 13 (a), the longitude and latitude are used as coordinates, and an area surrounded by the coordinates is designated as an area where file decoding is permitted. Although not shown, it is assumed that a map of a predetermined area is displayed in the background. In addition, as shown in FIG. 13B, it is possible to provide a region 1303 in which file decryption is rejected in a region 1302 in which file decryption is permitted. This can be achieved by providing an area setting for rejecting file decoding to be superior to an area setting for permitting file decoding. When designation is made as 1303 in FIG. 13 (b), the region data 703 in the file decryption permitted position data described in FIG. This information is also stored.

  In this case, as a region specifying method, a polygonal region may be specified by arranging a plurality of latitudes / longitudes.

  On the other hand, in the method of designating an area stored in the map database 202 in advance, an area where file decryption is permitted is designated using an address and a place name or a building name.

  When location information permitting file decryption is specified in step 1203, the terminal device 103 uses a file encryption key for encrypting file data, using the encryption key acquired from the server 102 and the file decryption permitted area. (Step 1204). That is, the key for encrypting the file data is created as needed depending on the region where the file is permitted to be decrypted. The file is encrypted using the file encryption key created in step 1204 and the encryption key transmitted from the server (steps 1205 and 1206).

  Note that the server 102 that has received the encryption key acquisition request from the terminal device 103 in step 1202 of FIG. 12 is a terminal in which the terminal device 103 is officially registered with reference to the terminal database 116 of FIG. If the terminal is an officially registered terminal, the terminal device 103 generates and transmits an encryption key used for encryption. The server 102 stores and manages the encryption key in a predetermined database (or the terminal database 116 in FIG. 8) in association with the terminal device 103.

  FIG. 14 shows how the file data is encrypted in the position encryption processing in steps 1205 and 1206 executed by the encryption processing unit 209 of the terminal device 103. A file data part 1401 in FIG. 14A shows file data to be encrypted. The file data unit 1401 is encrypted with the file encryption key generated from the encryption key transmitted from the server 102 and the position information data (file decryption permission position) permitting decryption of the file. Reference numeral 1402 in FIG. 14B denotes an encrypted file data portion. Next, as shown in FIG. 14C, position information data 1403 that permits decryption of a plain text file is added to the encrypted file data portion 1402. The encrypted file data portion 1402 and the position information data 1403 that permits decryption of the plain text file are encrypted using the encryption key transmitted from the server 102 to create an encrypted file 1401 with position information. (FIG. 14 (d)).

  FIG. 15 is a flowchart showing the decryption processing of the encrypted file with position information executed by the decryption processing unit 210 of the terminal device 201 (103). First, the terminal device 103 determines whether a valid file decryption key has been acquired from the server 102 (step 1501). If a valid decryption key has not been obtained from the server 102, the server 102 is connected to obtain a decryption key (step 1502).

  Next, in order to acquire the position information of the terminal device 103, the position information acquisition unit 207 of the terminal device connects to the GPS unit 204 and acquires the current position information of the terminal device 103 (step 1503). The encrypted file with position information to be decrypted is decrypted using the decryption key transmitted from the server 102, and encrypted with the decryption permission position of the file (file decryption permission position data section 1403 in FIG. 14 (c)). The file data part (file data part 1402 in FIG. 14C) is acquired. It is determined whether or not the current position of the terminal device acquired from the GPS unit 204 is within the decryption permission position of the file (step 1504). If the current position of the terminal device is not within the file decryption permission position, decryption is not permitted and the process returns to step 1501. If the current position of the terminal device is within the decryption permission position of the file, a file decryption key is created using the decryption key acquired from the server 102 and the decryption permission position data of the file (step 1505). The target file data is decrypted using the file decryption key (step 1506).

  The server 102 that has received the decryption key acquisition request from the terminal device 103 in step 1502 of FIG. 15 is a terminal in which the terminal device 103 is officially registered with reference to the terminal database 116 of FIG. If the terminal is an officially registered terminal, the terminal device 103 transmits a decryption key used for decryption. This decryption key is a decryption key corresponding to the encryption key sent from the server 102 to the terminal device 103 in step 1202 of FIG.

As described above, the position information encryption system according to the present embodiment has the following effects.
(1) A file that can be used only in a high security area can be created.
(2) The location of the file taken out can be specified using map data or the like.
(3) The location of the file can be specified even when the file name of the file taken out is changed.
(4) The position history of the file taken out can be checked.
(5) The location can be specified even when the file taken out is copied.
(6) A place where the terminal device can be used can be specified.
(7) The file can be used in two ways: a method set on the server side and a method set on the user side. The file can be used in the latest map with longitude, latitude, and usage. Can be specified by address, building, etc.
(8) A map used within the usable range of the file can be received from the host system at any time.
(9) Since the host system holds the contract information of the server, the latest map request from a party other than the contractor can be eliminated.

  In the above-described embodiment, an example in which a file is encrypted has been described. However, a folder may be specified instead of a file, and all files in the folder may be similarly encrypted. In the above embodiment, the terminal device communicates with the server to perform encryption and decryption. However, the present invention can also be applied to a terminal device that is not connected to the network. Before performing encryption or decryption, obtain an encryption key or decryption key from the server, and in encryption, skip steps 1201 to 1202 in FIG. Then, step 1501 to step 1502 in FIG. If the encrypted file with location information is operated on a terminal device that is not connected to the network, the history is stored in the terminal device and stored when the file is connected to the network later. The history information may be sent to the server and stored in the file position information history database 114 of FIG.

1 is a system configuration diagram illustrating an embodiment of the present invention. It is a block diagram of a terminal device. It is a data table of map data and map related information stored in the updated partial map database of the host system. It is a block diagram of district ID data of map data. It is a block diagram of the contract information data of the location information encryption contractor stored in the server information database of the host system. It is a block diagram of the file position information history information data stored in the file position information history database of the server. It is a block diagram of the decoding permission position data of the file stored in the file decoding permission position database of a server. It is a block diagram of the information data of the terminal device stored in the terminal database of a server. It is a flowchart which shows the outline | summary of a server information addition process. It is a flowchart which shows the outline | summary of a terminal device addition process. It is a flowchart which shows the update process of the map information data of a server. It is a flowchart which shows the encryption process of the file performed in the encryption process part of a terminal device. It is a schematic diagram which shows the designation | designated method of the area which permits the decoding of a file. It is a schematic diagram which shows the mode of the position encryption process of the file performed in the encryption process part of a terminal device. It is a flowchart which shows the position decoding process of the file performed in the decoding process part of a terminal device.

Explanation of symbols

  101 ... Host system, 107 ... Map database, 108 ... Update partial map database, 109 ... Server information database, 110 ... Database update unit, 111 ... Transmission / reception unit, 112 ... Server confirmation unit, 105, 106 ... Network, 102a, 102b, and 102n ... Servers 103a, 103b, and 103n ... Terminal devices.

Claims (7)

An encryption system with location information for encrypting files,
Means for encrypting the unencrypted file data body with a predetermined file encryption key;
Means for adding, to the encrypted file data main body, file decryption permission position data indicating an area where decryption of the file is permitted;
Means for encrypting the encrypted file data body to which the file decryption-permitted position data is added with a predetermined encryption key, and creating an encrypted file with position information. system. A file decryption system with position information for decrypting an encrypted file with position information encrypted by the encryption system with position information according to claim 1,
Means for obtaining a decryption key corresponding to the encryption key;
Means for decrypting the encrypted file with position information using the obtained decryption key, and obtaining the file decryption permitted position data and the encrypted file data body;
Means for obtaining the current position of the system;
Means for determining whether or not the current position is included in an area where decoding of the file indicated by the file decoding permission position data is permitted;
Only when the current position is included in the region where the decryption is permitted, obtains a file decryption key for decrypting the encrypted file data body, and uses the file decryption key to And a means for decrypting the file. An encryption system with location information for encrypting files,
A server and a terminal device connected to the network;
The server
Means for transmitting an encryption key in response to a request from the terminal device;
Means for storing the encryption key in association with the terminal device,
The terminal device
Means for obtaining an encryption key from the server;
Means for inputting file decryption permission position data indicating an area where decryption of the file is permitted;
Means for generating a file encryption key from the encryption key acquired from the server and the file decryption permission position data;
Means for encrypting an unencrypted file data body with the file encryption key;
Means for adding, to the encrypted file data main body, file decryption permission position data indicating an area where decryption of the file is permitted;
Means for encrypting the encrypted file data body to which the file decryption-permitted position data is added with an encryption key obtained from the server, and creating an encrypted file with position information. With encryption system. A file decryption system with position information for decrypting an encrypted file with position information encrypted by the encryption system with position information according to claim 3,
The server
Means for transmitting a decryption key corresponding to the encryption key in response to a request from the terminal device;
The terminal device
Means for obtaining a decryption key from the server;
Means for decrypting the encrypted file with position information using the obtained decryption key, and obtaining the file decryption permitted position data and the encrypted file data body;
Means for obtaining the current position of the terminal device;
Means for determining whether or not the current position is included in an area where decoding of the file indicated by the file decoding permission position data is permitted;
Only when the current position is included in the area where the decryption is permitted, a file decryption key for decrypting the encrypted file data main body portion from the decryption key acquired from the server and the file decryption permitted position data Means for generating;
Means for decrypting the encrypted file data body using the generated file decryption key. A decryption system with position information. The decoding system with position information according to claim 4,
The terminal device includes means for transmitting an operation history performed on the encrypted file with position information and a current position of the terminal device when the operation is performed to the server,
The server includes a means for storing an operation history transmitted from the terminal device and a current position of the terminal device in a file position information history database. An encryption method with location information for encrypting a file,
Connect the server and terminal device to the network,
Transmitting an encryption key acquisition request from the terminal device to the server;
The server transmitting an encryption key in response to the encryption key acquisition request;
Storing the encryption key in the server in association with the terminal device;
Receiving at the terminal device an encryption key transmitted from the server;
In the terminal device, inputting file decryption permission position data indicating a region where file decryption is permitted;
In the terminal device, generating a file encryption key from the encryption key acquired from the server and the file decryption permission position data;
Encrypting unencrypted file data body with the file encryption key in the terminal device;
In the terminal device, adding to the encrypted file data main body file decryption permission position data indicating an area where decryption of the file is permitted;
And encrypting the encrypted file data body to which the file decryption permitted position data is added with the encryption key acquired from the server in the terminal device, and creating an encrypted file with position information. An encryption method with location information as a feature. A file decryption method with location information for decrypting an encrypted file with location information encrypted by the encryption method with location information according to claim 6,
Transmitting a decryption key acquisition request from the terminal device to the server;
In response to the decryption key acquisition request, the server transmits a decryption key corresponding to the encryption key;
Receiving at the terminal device a decryption key transmitted from the server;
In the terminal device, decrypting the encrypted file with position information using the decryption key, and obtaining the file decryption permitted position data and the encrypted file data body;
In the terminal device, obtaining a current position of the terminal device;
In the terminal device, the step of determining whether or not the current position is included in an area where decoding of the file indicated by the file decoding permission position data is permitted;
In the terminal device, only when the current position is included in the region where the decryption is permitted, to decrypt the encrypted file data main body portion from the decryption key acquired from the server and the file decryption permitted position data. Generating a file decryption key for:
And decrypting the encrypted file data main body using the generated file decryption key in the terminal device.

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