JP4635632B2 - File lock / unlock program, recording medium, and electronic file transfer processing system - Google Patents

Description

  The present invention relates to a file lock / unlock program for causing a computer to function to lock a file to an electronic file stored in a storage device provided in a PC (Personal Computer) or a storage medium, and the file lock / unlock program. The present invention relates to a recorded computer-readable recording medium and an electronic file transfer processing system.

  An electronic file in which computerized information handled by a PC (Personal Computer) or the like is written may contain highly confidential information. For example, in a company or the like, confidential information is stored as an electronic file in a storage means such as an HD (Hard Disk) provided in a PC, and even an individual user wants to avoid being freely viewed by others. Are stored in the HD of the PC.

  These highly confidential electronic files need to be used only by a limited number of users such as companies and individuals who own the electronic files, avoiding unauthorized use by third parties other than the parties. In order to prevent such unauthorized use of the electronic file by a third party, for example, there is a technique of managing and restricting the use authority of the PC in which the electronic file is stored with a password or the like.

  However, even if the PC is simply managed with a password and the use authority is limited, if the PC is connected to the network, there is a possibility that the electronic file is illegally acquired. Further, when the electronic file is stored in a removable storage medium or a portable PC and carried, there is a possibility that the electronic file is illegally acquired by a third party due to loss or theft.

  Therefore, a method has been devised in which a password is given to each electronic file to restrict the use of the electronic file, that is, the electronic file is locked by registering the password. For example, word software (manufactured by Microsoft), which is word processor application software that is installed and used on a general-purpose PC, has a function of locking electronic files by password. An electronic file created with this word and password-locked cannot be opened unless a password is entered.

JP 2002-215463 A

  However, when the method of registering a password for each electronic file as described above is used, a very complicated operation is required when locking a plurality of electronic files. For example, if the password is changed for each electronic file in order to enhance security, there is a problem that the burden on the user increases when a plurality of electronic files are locked.

  Furthermore, when an electronic file commonly used by a plurality of users is locked, there is a problem that a very complicated operation such as how to notify the user of a common password is required.

  Therefore, the present invention has been devised to solve such a problem, and it is possible to prevent an unauthorized use by a third party without performing a complicated operation. An object of the present invention is to provide a file lock / unlock program for causing a computer to function as a file lock, a computer-readable recording medium on which the file lock / unlock program is recorded, and an electronic file transfer processing system. .

  In order to achieve the above object, a file locking / unlocking program according to the present invention includes a computer, a compression processing unit that compresses an electronic file, and the electronic file that has been subjected to compression processing. Header information adding means for adding, as header information, a plurality of file lock information used for the lock process and a first hash value obtained by hashing the plurality of file lock information, and at least according to the file lock request, Group ID information for identifying a group to which the file lock / unlock program that is requested at the time of file unlock belongs is added as the file lock information, and the plurality of file lock information including the group ID information is hashed. By updating the first hash value, File locking means for applying a file lock that restricts the use of the compressed electronic file, and file locking is performed in response to a file unlock request for the compressed electronic file that has been locked by the file locking means. Hash value comparison means for comparing the second hash value obtained by hashing the file lock information added as the header information to the electronic file and the first hash value added as the header information And the group ID information added as the file lock information in response to the first hash value and the second hash value matching as a result of the comparison by the hash value comparison means, Identify the group to which the file lock / unlock program belongs When the group ID information is compared with the group ID information comparing means for comparing the group ID information and the group ID information comparing means is matched, the file lock of the compressed electronic file is released. This is realized by functioning as a file unlocking unit that performs file unlocking and a decompression processing unit that decompresses the electronic file that has been subjected to the compression process.

  In order to achieve the above object, a computer-readable recording medium on which a file locking / unlocking program according to the present invention is recorded is subjected to compression processing means for compressing an electronic file and a computer. Header information adding means for adding a plurality of file lock information used for file lock processing of the electronic file and a first hash value obtained by hashing the plurality of file lock information to the electronic file as header information. In response to the file lock request, at least group ID information for identifying a group to which the file lock / unlock program requested at the time of file unlock belongs is added as the file lock information, and the group ID information is Including the above multiple file lock information And updating the first hash value so as to update the compressed electronic file by using a file lock means for restricting the use of the file, and the compression processing performed by the file lock means. In response to a file unlock request for the electronic file, a second hash value obtained by hashing the file lock information added as the header information to the electronic file that has been file-locked and the header information are added. In addition, as a result of comparison between the hash value comparison unit that compares the first hash value and the hash value comparison unit, the first hash value matches the second hash value, The group ID information added as the file lock information and the file lock When the group ID information comparing means for comparing the group ID information for identifying the group to which the unlocking program belongs is compared with the group ID information comparing means, the group ID information matches, and the compression processing is performed. A file unlocking unit that performs file unlocking for releasing the file lock of the electronic file and a program for functioning as a decompression processing unit for decompressing the compressed electronic file that has been unlocked It is realized by doing.

  Furthermore, in order to achieve the above-described object, an electronic file transfer processing system according to the present invention includes a file lock processing device that performs file lock processing that restricts use of an electronic file, and a predetermined file lock processing device. And an electronic file transfer processing system comprising a storage medium having a storage means for storing the electronic file, wherein the file lock processing device is connected via the predetermined connection interface. A compression processing means for compressing the transferred electronic file in response to the transfer of the electronic file to the storage means of the storage medium connected to the file lock processing device; A copy of the electronic file used for file lock processing of the electronic file. Header information adding means for adding, as header information, the first hash value obtained by hashing the plurality of file lock information, and at least the file lock / unlock required when the file is unlocked Group ID information for identifying a group to which the lock program belongs is added as the file lock information, and the plurality of file lock information including the group ID information is hashed to update the first hash value. And a file lock means for performing file lock for restricting use of the compressed electronic file.

  In the present invention, when a file is locked, the electronic file is first compressed, so that the file can be decompressed only by a decompression process using a dedicated file lock / unlock program. To eliminate. A file lock is applied to the compressed electronic file by adding a plurality of file lock information including group ID information as header information.

  As a result, when the decompression process is executed by the dedicated file lock / unlock program, the file lock information added as the header information is shifted to a file unlock state in which the execution of the decompression process is permitted. Can be used as a condition. That is, when the condition of the header information is satisfied, the dedicated file lock / unlock program can perform the file unlock process. Accordingly, since the file unlock process can be executed only by a dedicated file lock / unlock program given only to a legitimate user, it is possible to eliminate an unauthorized decompression process by a third party.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited to the following examples, It cannot be overemphasized that it can change arbitrarily in the range which does not deviate from the summary of this invention.

{First embodiment}
First, the first embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, the first embodiment is a network system including general-purpose PCs (Personal Computers) 10 and 20 connected via a network 50 such as the Internet. In FIG. 1, only the PCs 10 and 20 are shown as PCs constituting the network system. However, it is assumed that a plurality of PCs other than the PCs 10 and 20 can be connected to the network 50.

  The PCs 10 and 20 are general-purpose PCs, which are input devices such as a keyboard and a mouse, output devices such as a monitor and a speaker, a main storage device such as a semiconductor memory, an arithmetic device such as a CPU (Central Processing Unit), and a control. Equipment. Further, as an auxiliary storage device, a large-capacity storage medium such as an HD (Hard Disk) is provided. Although not shown, the PC 10 and the PC 20 are CD (Compact Disc) -ROM (Read Only Memory), CD-R, CD-RW (ReWritable), DVD (Digital Versatile Disc) -ROM, DVD-RAM, DVD-. A multi-disk drive for driving a removable mass storage medium such as R, DVD-RW, DVD-R, DVD + RW is connected.

  Furthermore, the PCs 10 and 20 are provided with USB jacks 11 and 21 to which USB (Universal Serial Bus) devices can be connected, respectively. For example, a removable storage medium (USB memory) is connected to the USB jacks 11 and 21 to exchange information with the PCs 10 and 20.

  Such PCs 10 and 20 execute use (viewing) of desired electronic files by executing file lock / unlock application software (hereinafter referred to as file lock software) installed in the PCs 10 and 20 in advance. Editing, execution, etc.) can be locked to a specific user. The file lock application software can also release a file lock (file unlock) of a file-locked electronic file.

  The file lock software may be provided by being stored in a storage medium that can be mounted on the multi-disk drive described above. The file lock software is read from the storage medium mounted on the multi-disk drive, and the PC 10, PC 20 Thus, a desired file lock process or file unlock process is executed.

  The file lock software performs a data compression process to reduce the capacity of the electronic file according to a certain procedure while maintaining the meaning of the data, and uses the header information attached during the data compression process to lock the file. It is software that performs. The file locking software is software that releases the file lock by performing a decompression process on the file-locked electronic file. That is, the file lock software has a file lock function and a file unlock function.

  When unlocking a file-locked electronic file, use not only file locking software with file locking and file unlocking functions, but also file unlocking software dedicated to decompression processing. You can also.

  Generally, data compression / decompression processing for electronic files is executed by dedicated application software. The compressed electronic file cannot be browsed correctly unless the decompression process is executed with dedicated application software. Even if an electronic file subjected to data compression processing is opened with appropriate application software, it is not possible to obtain accurate information as if it were encrypted.

  The file lock software installed in the PCs 10 and 20 makes use of such a characteristic in the data compression processing and applies file lock that gives a user's use restriction to a desired electronic file.

  Next, the file lock processing operation by the file lock software will be described using the flowcharts shown in FIGS. The file lock processing operation will be described using the PC 10 shown in FIG.

In order to perform file lock on a desired electronic file, first, the electronic file is compressed as shown in the flowchart of FIG. The user requests that the target electronic file before compression be compressed with file locking software (step S1). For example, as shown in FIG. 3, the user uses a mouse to display a file icon A _ICN , which is an icon of the electronic file A before compression, displayed on the monitor 10a of the PC 10 with a GUI (Graphical User Interface). A compression processing request is made by dragging and dropping to the software icon LS _ICN , which is an icon of.

  In response to this, the PC 10 executes file locking software and compresses the electronic file A (step S2).

  Further, the file locking software executed by the PC 10 adds a header portion including information for file locking to the electronic file A subjected to the compression process (step S3). Thus, the electronic file AC compressed by the file lock software and added with the header is placed under the directory of the compressed folder generated by the file lock software.

For example, as shown in FIG. 3, on the monitor 10a of the PC 10, a file icon AC _ICN that is an icon of an electronic file AC is displayed in a GUI in a folder icon CF _ICN that is an icon of a compressed folder.

  At this point, the electronic file A is in a state where the file lock software has only been subjected to compression processing and the addition of a header portion, and has not yet been locked.

Therefore, when the electronic file AC is opened without using the file locking software by double-clicking the file icon AC _ICN with a mouse or the like, for example, the electronic file A before compression cannot be obtained. As shown in FIG. 4, the decompression process can be executed by dragging and dropping the file icon AC _ICN onto the software icon LS _ICN . When the decompression process is executed, the electronic file A after the decompression process is placed under the directory of the decompression folder. For example, as shown in FIG. 4, in the folder icon EF _ICN which is an icon of the decompression folder on the monitor 10a. The file icon A _ICN is displayed on the GUI.

<File structure of electronic file after compression>
FIG. 5 shows a file structure of the electronic file AC compressed by the file lock software. As shown in FIG. 5, the electronic file AC includes a data body portion BD that is a compressed data body and a header portion HED that includes header information for performing file locking. The data body BD is composed of, for example, compressed first to nth (n is a natural number) sector areas divided into sectors every 32 kB, and the compressed file data is stored in the compressed first to nth sector areas. Stored.

  For example, as shown in FIG. 5, the header information for performing the file lock is stored in the header sector HSEC of the header section HED, and includes 15 types (including the reserved area) of file lock information and the file lock. It consists of a hash value obtained by hashing business information. For example, a 256-byte data area is prepared for the header sector HSEC, and a 16-byte data area is allocated to the file lock information and the hash value.

  Assuming that each data area obtained by dividing the header sector HSEC into 16 is a first header sector area to a sixteenth header sector area, the following header information is stored in each header sector area.

  A system ID is stored as header information in the first header sector area. This system ID is an ID for specifying that the file lock software installed in the PC 10 is used.

  In the second header sector area, a group ID that is a hash value by a hash function is stored as header information. This group ID is an ID that is commonly assigned to a group that permits the decompression process, and is the same group ID as the file locking software or the file unlocking software having a file unlocking function used during the decompression process. The If a NULL value is set in the second header sector area, this indicates that file locking is not performed.

  In the third header sector area, a password having a hash value by a hash function is stored as header information. This password is registered by the user when the file lock process is performed. Since whether or not to register a password can be arbitrarily selected by the user, a NULL value is set when the password is not registered.

  In the fourth header sector area, password expiration date information specifying the expiration date of the password stored in the third header sector area is stored as header information. When this expiration date has passed, the decompression process cannot be executed even if a password is input during the decompression process. If no password is registered, a NULL value is set.

  The fifth header sector area is a reserved area.

  In the sixth header sector area, group ID setting date / time information for specifying the date / time (year / month / day / hour / minute / second) at which the group ID is set is stored as header information.

  In the seventh header sector area, password setting date / time information for specifying the date / time (year / month / day / hour / minute / second) at which the password is set is stored as header information.

  In the eighth header sector area, compressed file creation date / time information for specifying the date / time (year / month / day / hour / minute / second) of the electronic file to which the header portion is added is stored as header information. Is done.

  In the ninth header sector area, a part of data extracted from each of the compressed first to nth sector areas of the data body BD is stored as header information.

  In this way, by extracting a part of data from the compressed first to nth sector areas, for example, several bytes of data from the head of each sector and storing it in the header sector area as header information, the header part HED, The association with the data body BD can be strengthened. When the electronic file AC is decompressed, the extracted data is returned to the original location in the compressed first to nth sector areas when the user performing the decompression process is authenticated as a valid user. It is.

  That is, by extracting a part of data from the compressed first to nth sector areas and storing it as header information in the header sector HSEC, for example, a third party who is not a valid user for executing the decompression process Thus, it is possible to prevent an act of extracting only the data main body BD from the electronic file AC and executing the decompression process illegally.

  In the tenth header sector area, compression format information for specifying in which file compression format (for example, LZH format, ZIP format, etc.) the compression is stored as header information.

  In the eleventh header sector area, compression level information is stored as header information. Depending on the compression format stored in the 10th header sector area and specified by the compression format information, the compression rate may be arbitrarily set. Therefore, in the eleventh header sector area, this compression rate level is stored as compression level information.

  In the twelfth header sector area, the compression rate is stored as header information. For example, the compression rate is a value obtained by dividing the data capacity of the electronic file AC for compression by the data capacity of the electronic file A before being compressed.

  In the thirteenth header sector area, the data capacity of the electronic file A before being compressed is stored as header information.

  In the fourteenth header sector area, the data capacity of the compressed electronic file AC is stored as header information.

  In the fifteenth header sector area, a file name is stored as header information.

  In the sixteenth header sector area, a hash value obtained by a hash function using the file lock information stored in the first to fifteenth header sector areas is stored as a check code as header information. If any one of the header information stored in the compressed first to fifteenth sector areas of the header sector HSEC is falsified, the value of the hash value stored as the check code changes. This check code is header information prepared to prevent an unauthorized decompression process by a third party.

  In a state where the compression processing is performed and the header part HED is added before the file lock processing, NULL values are set in the second to fourth header sector areas, the sixth and seventh header sector areas of the header sector HSEC. ing.

<File lock processing operation>
Next, processing operations when the electronic file A is compressed and the electronic file AC to which the header portion HED is added are locked will be described with reference to the flowchart shown in FIG.

  In step S11, after the process of step S3 in the flowchart shown in FIG. 2 is completed, a file lock request is made to the electronic file AC.

For example, as shown in FIG. 7, on the monitor 10a of the PC 10, the icon of the electronic file AC and the file icon AC _ICN that are the object of file lock displayed on the GUI are selected (actively displayed) by the mouse operation, and a popup is displayed. The menu MN is displayed. When an item described as “file lock” is selected from the displayed pop-up menu MN with the mouse, a file lock request is made to the CPU of the PC 10 and the installed file lock software is started, and the electronic file AC is started. Is read out. Thereafter, the file lock software is executed by the CPU of the PC 10.

  In step S12, it is verified whether or not the system ID stored in the first header sector area matches the system ID of the file lock software. If they match, the process proceeds to step S13. If they do not match, the process ends.

  In step S13, a hash value is calculated from the header information stored in the first to fifteenth header sector areas using a hash function.

  In step S14, the hash value calculated in step S13 is compared with the check code stored in the fifteenth header sector area to determine whether or not they match. If they match, the process proceeds to step S15. If they do not match, the process ends.

  In step S15, a part of the data extracted from each of the compressed first to n sectors stored in the ninth header sector area is confirmed. If the stored data is data extracted from the compressed first to nth sectors, the process proceeds to step S16; otherwise, the process ends.

  In step S16, a hash value is calculated from the group ID given to the file lock software by a hash function and set in the second header sector area. Further, the date and time (year / month / day / hour / minute / second) at which the group ID is set is set in the sixth header sector area as the group ID setting date / time information.

  In step S17, it is determined whether or not to register a password in response to a user request. If the password is to be registered, the process proceeds to step S18. If the password is not registered, the process proceeds to step S20.

For example, after step S16 is completed, a password registration window _TWIN prompting the input of a password as shown in FIG. 8 is displayed on the monitor 10a of the PC 10. If the password is not registered, the “Cancel” button in the password registration window _TWIN is pressed.

  When no password is registered, NULL values are stored in the third header sector area and the seventh header sector area.

In step S18, the user inputs a password to the PC 10 through an input device such as a mouse or a keyboard. For example, as described above, after step S16 is completed, the password is input to the password registration window _TWIN displayed on the monitor 10a of the PC 10. The user will enter the password twice for confirmation.

  In step S19, a hash value is calculated from the input password by a hash function and set in the second header sector area. Also, the date and time (year / month / day / hour / minute / second) when the password is set is set in the seventh header sector area as the password setting date / time information.

In step S20, a hash value is calculated from the header information of the first to fifteenth header sector areas using a hash function, and set as a check code in the sixteenth header sector area. As a result, the electronic file AC that has been subjected to compression processing and to which the header portion HED has been added enters a file lock state. When the electronic file AC is locked, for example, a locked key indicating a locked state is displayed on the monitor 10a of the PC 10 like a file icon ACL _ICN shown in FIG.

<Unlock processing operation>
Next, the processing operation for unlocking the electronic file AC that has been file-locked will be described with reference to the flowchart shown in FIG.

  In step S31, the electronic file AC is requested to unlock the file.

For example, as shown in FIG. 10, on the monitor 10a of the PC 10, a GUI-displayed file-locked electronic file AC icon and file icon ACL _ICN to be unlocked are selected by a mouse operation, and a pop-up menu is displayed. Display MN. When an item described as “Unlock file” is selected from the displayed pop-up menu MN with the mouse, a request to unlock the file is made to the CPU of the PC 10 and the installed file lock software is started. Then, the file-locked electronic file AC is read out. Thereafter, the file lock software is executed by the CPU of the PC 10.

  In the flowchart shown in FIG. 9, the case where the CPU of the PC 10 executes file lock software having a file unlock function to unlock the electronic file AC that has been locked is described. Dedicated file unlocking software having only the unlock function may be executed.

  In step S32, it is verified whether or not the system ID stored in the first header sector area matches the system ID of the file lock software. If they match, the process proceeds to step S33, and if they do not match, the process ends.

  In step S33, a hash value is calculated from the header information stored in the first to fifteenth header sector areas using a hash function.

  In step S34, the hash value calculated in step S33 and the check code stored in the fifteenth header sector area are compared to determine whether or not they match. If they match, the process proceeds to step S35, and if they do not match, the process ends.

  In step S35, a part of data extracted from each of the compressed first to n sectors stored in the ninth header sector area is confirmed. If the stored data is data extracted from the compressed first to nth sectors, the process proceeds to step S36, and if not, the process ends.

  In step S36, the hashed group ID stored in the sixth header sector area is read and decoded.

  In step S37, the group ID given to the file lock software is compared with the decrypted group ID to determine whether or not they match. If the group IDs match, the process proceeds to step S38. If the group IDs do not match, the process ends.

  In step S38, it is determined whether or not the registered password stored in the third header sector area is a NULL value. If it is a NULL value, the process proceeds to step S39, and if it is not a NULL value, the process is terminated.

  In step S39, the hashed password stored in the third header sector area is read and decrypted.

  In step S40, the password expiration date information stored in the fourth header sector area is read out to determine whether or not the registered password has expired. If the password is within the expiration date, the process proceeds to step S41, and if the expiration date has passed, the process ends.

In step S41, the user inputs a password to the PC 10 through an input device such as a mouse or a keyboard. For example, after step S39 is completed, a password input window I _WIN for prompting a password as shown in FIG. 11 is displayed on the monitor 10a of the PC 10. A password is input to a password input window I _WIN displayed on the monitor 10a of the PC 10.

  In step S42, the password input in step S41 and the password decrypted in step S39 are compared to determine whether they match. If the passwords match, the process proceeds to step S43. If the passwords do not match, the process ends.

In step S43, the file lock of the electronic file AC that has been file-locked is released (unlocked). When the file-locked electronic file AC is unlocked, for example, the file icon ACL _ICN shown in FIG. 10 is locked on the monitor 10a of the PC 10 to indicate a locked state like the file icon AC _ICN . The key display disappears.

  Then, the file lock software decompresses the electronic file AC that has been subjected to compression processing, and returns it to the original electronic file A. At this time, the decompression process is performed using a part of data extracted from the compressed first to nth sectors stored in the ninth header sector area.

<Transmission processing of electronic file with file lock>
Next, in the network system shown in FIG. 1, the operation when the electronic file AC file-locked by the PC 10 is transmitted to the PC 20 via the network 50 will be described. In this case, as shown in FIG. 12, the electronic file ACL compressed with the file lock software installed in the PC 10 and added with the header is transmitted to the PC 20 via the network 50 such as the Internet. .

  At this time, if the group ID of the file lock software installed on the PC 20 is different from the group ID of the file lock software installed on the PC 10, the electronic file ACL transmitted from the PC 10 to the PC 20 is sent. It is necessary to simultaneously transmit file unlocking software ULS for decompression. The group ID of the file unlocking software ULS is the same as the group ID of the file locking software installed in the PC 10. The file unlocking software ULS is encrypted by an encryption process and transmitted.

  When a password is set in the electronic file ACL transmitted from the PC 10 to the PC 20, it is only necessary to notify the user who operates the PC 20 of the password separately. Thereby, even when the electronic file ACL is erroneously transmitted to a PC other than the PC 20, it is possible to avoid the possibility of being viewed and used by a third party.

  As described above, the file locking software using the compression process can lock a desired electronic file by a simple operation using the GUI of the PC 10 without necessarily performing a complicated operation such as inputting a password. . Even when file lock is applied to multiple electronic files, multiple target electronic files can be selected simultaneously in the GUI environment, and "drag and drop"-> "file lock execution by calling menu" by mouse operation By inputting the command, the file lock can be executed almost automatically.

  In addition, since the data compression processing is performed on the electronic file when the file is locked, the data capacity is reduced, for example, the network load when transferring through the network can be reduced, and the transfer time is reduced. There is also an advantage that can be greatly shortened.

  In the above description, when file locking an electronic file, data compression processing is performed by file locking software and header information is added. Instead, the electronic file is file locked. In doing so, the electronic file may be encrypted to add the header information as described above. The user installs software for performing encryption processing on the PC 10 and executes the installed software to encrypt a desired electronic file. At this time, the software encrypts the electronic file and adds header information as shown in FIG.

  The encrypted electronic file to which the header information is added cannot be decrypted unless decryption software having a matching system ID and group ID is used and a password is input as required. Therefore, the electronic file thus encrypted and added with the header information can generate the same effect as when the file lock is executed using the file lock software described above.

{Second Embodiment}
Subsequently, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, as illustrated in FIG. 13, a storage medium 100 that is a removable medium including a USB plug 101 connected to a USB jack 11 included in the PC 10 is used. The storage medium 100 includes a flash memory (not shown), and functions as a data storage of the PC 10, that is, an external memory when connected to the PC 10.

  In the flash memory (not shown) of the storage medium 100, the file lock software or the file unlock software installed in the PC 10 in the first embodiment is stored and used when the storage medium 100 is manufactured. .

  When the USB plug 101 is connected to the USB jack 11 of the PC 10, power is supplied to the storage medium 100, and file lock software or file unlock software stored in a flash memory (not shown) can be read.

  At this time, a plurality of storage media 100 storing file locking software or file unlocking software with the same group ID are stored in a group composed of a plurality of users, for example, people belonging to a department in a company. When distributed to each, the file unlocking software need not be transmitted every time as described with reference to FIG. In other words, since the file storage software or file unlock software with a common group ID is stored in advance in the storage medium 100, using this storage medium 100 belongs to the same group. It becomes easy to generate an electronic file that can be used only by a certain person, and it is possible to freely perform transmission through a network without worrying about unauthorized acquisition of the electronic file by a third party.

  By providing the storage medium 100 storing the file locking software or file unlocking software having a common group ID to users belonging to the same group, it is possible to use only the users belonging to this group. It is possible to provide a system that encrypts an electronic file with an encryption key and restricts use from users outside the group who do not have the encryption key by a simple method.

  Further, the storage medium 100 storing the file lock software is provided with an input device for inputting a password and biometric information, and an authentication processing device for performing a user authentication process based on the input password and biometric information. When the electronic file is transferred to the flash memory of the storage medium 100, the file locking software stored in the flash memory is automatically executed, and the electronic file can be locked. .

  In this way, the storage medium 100 is provided with an authentication mechanism for identifying the user, and the file locking software is automatically activated to perform file locking on the electronic file. Even if it is lost or stolen, unauthorized use of electronic media stored in the flash memory can be avoided.

It is a figure for demonstrating the network system shown as a 1st Embodiment of this invention. It is a flowchart for demonstrating the operation | movement which compresses an electronic file. It is the figure which showed the display screen of PC (Personal Computer) at the time of compressing an electronic file. It is the figure which showed the mode of the display screen of PC at the time of decompress | decompressing the electronic file by which the compression process was carried out. It is a figure for demonstrating the header information compressed and further added. It is a flowchart for demonstrating file lock processing operation. It is the figure shown about the operation display screen of PC at the time of a file lock process. It is the figure which showed an example of the password registration window. It is a flowchart for demonstrating file unlock processing operation | movement. It is the figure shown about the operation always screen of PC at the time of a file unlock process. It is the figure which showed an example of the password input window. It is a figure for demonstrating the case where an electronic file is transmitted via a network. It is a figure for demonstrating the storage medium used by connecting with PC shown as the 2nd Embodiment of this invention.

Explanation of symbols

10, 20 PC (Personal Computer), 11 USB (Universal Serial Bus) jack, 50 network, 100 storage media, 101 USB plug

Claims (21)

Computer
Compression processing means for compressing the electronic file;
A header that adds, as header information, a plurality of file lock information used for file lock processing of the electronic file and a first hash value obtained by hashing the plurality of file lock information to the compressed electronic file Information adding means;
In response to the file lock request, at least group ID information for identifying a group to which the file lock / unlock program requested at the time of file unlock belongs is added as the file lock information, and includes the group ID information. A file locking means for applying a file lock that restricts use of the compressed electronic file by hashing a plurality of file lock information and updating the first hash value;
In response to a file unlock request for the compressed electronic file that has been locked by the file locking means, the file locking information added as the header information to the electronic file that has been file-locked is hashed Hash value comparing means for comparing the second hash value and the first hash value added as the header information;
As a result of the comparison by the hash value comparison means, the group ID information added as the file lock information according to the fact that the first hash value and the second hash value match, and the file Group ID information comparing means for comparing the group ID information for identifying the group to which the lock / unlock program belongs;
As a result of comparison by the group ID information comparison means, a file unlock means for performing file unlock for releasing the file lock of the compressed electronic file in accordance with the match of the group ID information;
A file lock / unlock program for functioning as a decompression processing means for decompressing the electronic file that has been compressed and unlocked. 2. The file lock / unlock program according to claim 1, wherein the file lock means adds the hashed group ID information as the file lock information. The header information adding means, as one of the file lock information added as the header information, is a process by which the compression process and file lock process for the electronic file are executed by the computer executing the file lock / unlock program. The file lock / unlock program according to claim 1, further comprising system ID (IDentification) information for specifying In response to a file unlock request for the compressed electronic file that has been locked by the file lock means,
The above computer
Based on the system ID information that is the file lock information of the electronic file, it is verified that the compression process and the file lock process for the electronic file are processes by the execution of the file lock / unlock program by the computer. System ID information verification means;
4. The file locking / unlocking program according to claim 3, wherein the file locking / unlocking program is made to function as the hash value comparing unit in accordance with a verification result by the system ID information verifying unit. The header information adding means, as one of the plurality of file lock information that is the header information, has a predetermined compression sector from each compression sector of the electronic file compressed by the compression processing means in a predetermined compression sector unit. The file lock / unlock program according to claim 1, wherein the data amount data is extracted. The decompression processing means decompresses the compressed electronic file using the data having a predetermined data amount extracted from each compression sector, which is one of the file lock information. 6. The file lock / unlock program according to claim 5. In response to the above file lock request,
The above computer
Function as a password registration means to register passwords,
2. The file lock / unlock program according to claim 1, wherein the file lock means hashes the registered password and adds it as the file lock information. Furthermore, as a result of comparison by the group ID information comparison means, the group ID information matches,
The above computer
A password input means for entering a password;
It functions as a password comparison means that compares the entered password with the password registered as the file lock information.
The file unlocking means is a file of the electronic file that has been compressed in response to the input password and the password registered as the file lock information being matched as a result of the comparison by the password comparing means. 8. The file lock / unlock program according to claim 7, wherein file unlock is performed to release the lock. Computer
Compression processing means for compressing the electronic file;
A header that adds, as header information, a plurality of file lock information used for file lock processing of the electronic file and a first hash value obtained by hashing the plurality of file lock information to the compressed electronic file Information adding means;
In response to the file lock request, at least group ID information for identifying a group to which the file lock / unlock program requested at the time of file unlock belongs is added as the file lock information, and includes the group ID information. A file locking means for applying a file lock that restricts use of the compressed electronic file by hashing a plurality of file lock information and updating the first hash value;
In response to a file unlock request for the compressed electronic file that has been locked by the file locking means, the file locking information added as the header information to the electronic file that has been file-locked is hashed Hash value comparing means for comparing the second hash value and the first hash value added as the header information;
As a result of the comparison by the hash value comparison means, the group ID information added as the file lock information according to the fact that the first hash value and the second hash value match, and the file Group ID information comparing means for comparing the group ID information for identifying the group to which the lock / unlock program belongs;
As a result of comparison by the group ID information comparison means, a file unlock means for performing file unlock for releasing the file lock of the compressed electronic file in accordance with the match of the group ID information;
A computer-readable recording medium having recorded thereon a file lock / unlock program for functioning as a decompression processing means for decompressing the electronic file that has been subjected to the compression process. 10. The computer-readable recording medium according to claim 9, wherein said file lock means records the file lock / unlock program, wherein said hashed group ID information is added as said file lock information. The header information adding means, as one of the file lock information added as the header information, is a process by which the compression process and file lock process for the electronic file are executed by the computer executing the file lock / unlock program. 10. The computer-readable recording medium according to claim 9, wherein a file lock / unlock program is recorded, which includes system ID (IDentification) information for specifying that the file is locked. In response to a file unlock request for the compressed electronic file that has been locked by the file lock means,
The above computer
Based on the system ID information that is the file lock information of the electronic file, it is verified that the compression process and the file lock process for the electronic file are processes by the execution of the file lock / unlock program by the computer. System ID information verification means;
12. The computer-readable recording medium according to claim 11, wherein a file lock / unlock program that functions as the hash value comparison unit is recorded according to a verification result by the system ID information verification unit. The header information adding means, as one of the plurality of file lock information that is the header information, has a predetermined compression sector from each compression sector of the electronic file compressed by the compression processing means in a predetermined compression sector unit. 10. The computer-readable recording medium according to claim 9, wherein a file locking / unlocking program is recorded, wherein a data amount data is extracted. The decompression processing means decompresses the compressed electronic file using the data having a predetermined data amount extracted from each compression sector, which is one of the file lock information. 14. A computer-readable recording medium according to claim 13, wherein a file lock / unlock program is recorded. In response to the above file lock request,
The above computer
Record the program that functions as a password registration means to register the password,
10. The computer-readable recording medium according to claim 9, wherein said file lock means has recorded the file lock / unlock program recorded by hashing the registered password and adding it as the file lock information . Furthermore, as a result of comparison by the group ID information comparison means, the group ID information matches,
The above computer
A password input means for entering a password;
Record a file lock / unlock program that functions as a password comparison means for comparing the entered password with the password registered as the file lock information,
The file unlocking means is a file of the electronic file that has been compressed in response to the input password and the password registered as the file lock information being matched as a result of the comparison by the password comparing means. 16. The computer-readable recording medium according to claim 15, wherein a file locking / unlocking program is recorded, wherein file unlocking for unlocking is performed. A file lock processing device that performs file lock processing that restricts use of an electronic file, and a storage medium that can be freely connected to the file lock processing device via a predetermined connection interface and has storage means for storing the electronic file An electronic file transfer processing system comprising:
The file lock processing device transfers the electronic file transferred in response to the transfer of the electronic file to the storage means of the storage medium connected to the file lock processing device via the predetermined connection interface. Compression processing means for compressing the file;
A header that adds, as header information, a plurality of file lock information used for file lock processing of the electronic file and a first hash value obtained by hashing the plurality of file lock information to the compressed electronic file Information adding means;
At least group ID information for identifying a group to which the file locking / unlocking program requested at the time of file unlocking belongs is added as the file locking information, and the plurality of file locking information including the group ID information is added. An electronic file transfer processing system comprising: file lock means for performing file lock for restricting use of the compressed electronic file by hashing and updating the first hash value. The file lock processing device adds the header information to the electronic file that has been file-locked in response to a file unlock request for the compressed electronic file that has been file-locked by the file lock means. A hash value comparison means for comparing the second hash value obtained by hashing the file lock information with the first hash value added as the header information;
As a result of the comparison by the hash value comparison means, the group ID information added as the file lock information according to the fact that the first hash value and the second hash value match, and the file Group ID information comparing means for comparing the group ID information for identifying the group to which the lock / unlock program belongs;
As a result of comparison by the group ID information comparison means, a file unlock means for performing file unlock for releasing the file lock of the compressed electronic file in accordance with the match of the group ID information;
18. The electronic file transfer processing system according to claim 17, further comprising a decompression processing unit that decompresses the electronic file that has been subjected to the compression processing in which the file is unlocked. The electronic file transfer processing system according to claim 17, wherein the connection interface is a USB (Universal Serial Bus) interface. The storage medium includes input means for inputting authentication information;
Authentication processing means for performing authentication processing of the authentication target information input by the input means,
19. The electronic file transfer processing system according to claim 18, wherein a file unlock request is made to the file lock processing device in accordance with an authentication processing result by the authentication processing means. The input means inputs biometric information as authenticated information,
21. The electronic file transfer processing system according to claim 20, wherein the authentication processing means performs an authentication process on the biometric information input by the input means.

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