JP2008097301A - File management server, program thereof and file management method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a file management server capable of managing the copy file or time stamp data of a storage file to be made correspond to each other, and to enable detecting the alternation of the file and restoring the file. <P>SOLUTION: The file management server for managing a file by a shared folder is provided with: a file management table for registering the copy file of a reception file and the time stamp data; and a history management table for acquiring the history of file editing. The presence/absence of alternation to the file is performed by using the time stamp data with a predetermined time interval, and the restoration of the file is operated by using the copy file when the alternation is detected. Thus, the history of the file content is prepared in editing the file so that it is possible to confirm the state or content of the history. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a file management server connected to a network, a program thereof, and a file management method, and more particularly to file management for guaranteeing the originality of a file to be stored and detecting alteration of the file and restoring it.

In an editable data storage device, it is known to attach time authentication to data to create non-editable data and transmit it (Patent Document 1). However, it only guarantees the originality of the stored document, and does not detect, for example, falsification of the stored document and notify the user of this, or restore the falsified document.
JP-A-2005-151358

  SUMMARY OF THE INVENTION An object of the present invention is to provide a file management server with a time stamp attached to an electronic file, guarantee originality, manage the file, and make the file freely accessible. 4, 7).

An additional problem of the present invention is to detect edits to a file to be stored and manage the history of editing (claims 2, 5, and 8).
A further additional object of the present invention is to monitor unauthorized alteration and restore a file when the alteration is detected (claims 3, 6 and 9).

  The present invention provides a file management server for managing a document file on a network, a receiving means for receiving the document file via the network, and a copy creating means for creating a copy file of the received document file. A time stamp data acquisition unit for acquiring time stamp data in the received document file, a copy file created by the copy creation unit, and a time stamp data acquired by the time stamp data acquisition unit Registering means for registering in the file management table, and the received document file is stored in a shared folder accessible from a client on the network (claim 1).

  Preferably, there is provided an edit detection means for detecting whether or not the saved file in the shared folder is edited using the time stamp data, and when detecting that the saved file is edited, the file management table The above copy file and time-sampling data are registered in the history management table, and the copy file of the edited file is created by the copy creating means, and the time stamp data of the edited file is created by the time stamp. Acquired by the data acquisition means, the copy file and the time stamp data are associated with each other and registered in the file management table (claim 2).

  Preferably, when a falsification monitoring unit for monitoring the presence / absence of falsification of the shared folder using the corresponding time stamp data on the file management table, and falsification of the saved file are detected, Falsification information output means for outputting falsification information, a file repair means for obtaining a copy file of the falsified file from the file management table, and saving it in the shared folder instead of the falsified file; (Claim 3).

  Furthermore, the present invention provides a file management server program for managing a document file on a network, for creating a command for receiving the document file via the network and a copy file of the received document file. An instruction for acquiring time stamp data in the received document file, and an instruction for associating the created copy file with the acquired time stamp data in the file management table. The received document file is stored in a shared folder accessible from a client on the network (claim 4).

  Preferably, a command for detecting whether or not the storage file is edited using the time stamp data and a copy on the file management table are detected when the storage file is edited. A command for registering a file and time-sampling data in a history management table; a command for creating a copy file of the edited file; and a command for acquiring time-stamp data of the edited file; And an instruction for associating these copy files with the time stamp data and registering them in the file management table (claim 5).

  More preferably, an instruction for monitoring the presence or absence of falsification of the shared folder using the corresponding time stamp data on the file management table and falsification information when detecting falsification of the saved file. And a command for obtaining a copy file of the altered file from the file management table, and for saving the obtained copy file in the shared folder in place of the altered file. And an instruction (Claim 6).

  Furthermore, the present invention provides a method for managing a document file on a network using a file management server, comprising: a step for receiving the document file via the network; and a copy file of the received document file. A step for creating, a step for obtaining time stamp data in the received document file, and a step for associating the copy file with the time stamp data and registering them in the file management table. The received document file is stored in a shared folder accessible from a client on the network (claim 7).

  More preferably, a step for detecting whether or not the storage file is edited in the storage file using the time stamp data, and when detecting that the storage file is edited, on the file management table A step for registering a copy file and timestamp data in a history management table; a step for creating a copy file of the edited file; and a step for acquiring time stamp data of the edited file And a step for associating these copy files with the time stamp data and registering them in the file management table.

  Preferably, a step for monitoring whether or not the saved file has been tampered with using the corresponding time stamp data on the file management table, and tampering information upon detection of tampering with the saved file. For outputting a copy file of the altered file from the file management table, and for saving the obtained copy file in the shared folder in place of the altered file And a step (claim 9).

  In the present invention, a copy file of a document file to be stored and time stamp data are associated with each other and registered in the file management table to be managed centrally. Since the document file is backed up and client access is permitted, access can be made while guaranteeing the originality of the shared file (claims 1, 4 and 7).

  Furthermore, according to the present invention, when editing a document file, the copy file and time stamp data of the original file are registered in the history management table, and the copy file and time stamp data of the edited document file are registered in the file management table. Register each time. Therefore, even if editing is performed a plurality of times, the history of editing the document file from the original state can be obtained (claims 2, 5 and 8).

  Further, according to the present invention, it is possible to monitor whether or not the stored file has been tampered with. If the hash value of the document file and its time stamp data do not match, it is assumed that the document has been tampered with, and the contents of the document file can be restored using the corresponding copy file and matched with the editing history. 3, 6, 9).

  In the following, an optimum embodiment for carrying out the invention will be shown.

  An example is shown in FIGS. FIG. 1 shows the relationship between the configuration of the file management server 2 and the time stamp server 4 or the like. In the embodiment, a file management server as a single device will be described. However, the file management server may be incorporated in an Internet facsimile machine or the like. The file management server 2 is connected to the client personal computer 8 and the router 10 via the LAN 6 and further connected to other personal computers 14 and the time stamp server 4 via the Internet 12.

  In FIG. 1, a time stamp server 4 is a server as a third party that provides a time stamping service. The time stamp server 4 assigns an electronic signature to file data from the file management server 2, that is, a hash value of the file data, a server name, time information, etc., and acquires time stamp data. Time stamp data is acquired by returning to.

  In the file management server 2 according to the embodiment, for example, a document created by the personal computer 8 is managed as an electronic file. However, when the file management server 2 is incorporated in a multifunction machine or the like, for example, a received e-mail attached file is a document. It may be managed as a file, and the file data is image data or binary data. In the figure, 20 is a main control unit, 22 is a LAN interface, and 24 is a data transmission / reception unit from the client personal computer 8 or the like. The RAM 26 stores a file folder (file folder 80 in FIGS. 3 and 4) for storing a document file, its time stamp data, and other data. The ROM 28 stores necessary programs in the file management server 2, and in particular creates a copy file of the document file, acquires time stamp data, registers these data in association with the table, and stores the document file. The file management program 60 necessary for performing editing and alteration detection and restoring the document file in response to unauthorized alteration is stored.

  30 is a file copy creation unit 30 for creating a copy file of the received document file, 32 is a message digest creation unit for creating a message digest of file data, and 34 is a message digest generated. On the other hand, it is a time stamp data acquisition unit for acquiring time stamp data by the time stamp server 4 or the like and assigning the time stamp. Reference numeral 36 denotes a file registration unit for registering the created copy file and the acquired time stamp data in the file management table 38 in association with each other.

  Reference numeral 40 denotes a client authentication unit for permitting a client who has logged in to the file management server 2 to access a document file in the file folder 80 stored in the RAM 26 or the like. A file editing processing unit 42 detects editing of the document file using the time stamp data, and copies the edited file and the time stamp data from the file management table 38 to the history management table 44 for management. To do.

  A time stamp data verification unit 46 obtains a hash value (message digest) of the document file to be stored, compares it with the hash value included in the corresponding time stamp data, and detects the presence or absence of falsification or the like. When tampering is detected, an alert information output unit 48 for outputting the fact is provided. The file restoration processing unit 50 obtains a copy file of the altered file from the file management table 38, restores the file, and saves it as a document file.

  In the embodiment, the time stamp data is acquired from the time stamp server 4, but the time stamp data may be generated for the data of the electronic file by itself without using the time stamp server 4. In this case, a standard time information acquisition unit is provided instead of the time stamp data acquisition unit 34, and only the time information is obtained from an external server or a server in the LAN 6, and a message digest is generated for the character data and the time information. Generated by the unit 32. Alternatively, the time information of the own device is used and a message digest is generated for these. In addition, a time stamp may be easily given using the own machine or a server in the LAN 6.

  FIG. 2 shows an outline of the file management program 60. The file management program 60 is stored in the file management server 2, manages the copy file of the document file and the time stamp data with the file management table, verifies the saved file with the time stamp data, and edits or alters the saved file. Is detected, the history of editing is managed in the history management table, and the file is restored when tampering is detected. The program 60 registers an instruction 62 for creating a copy file of the received document file, an instruction 64 for acquiring the time stamp data of the document file from an external server, and the like in association with each other in the file management table. An instruction 66 for verifying editing or falsification of a file to be stored with time stamp data, an instruction 70 for registering an editing history in the history management table when editing to a file is detected, This is composed of an instruction 72 for restoring a file using a copy file upon detection of alteration of the file.

  FIG. 3 shows processing of file data in the embodiment. In the embodiment, the received document file is stored in the file folder 80 shared by the client, and access to the file is permitted. The document file “File01” in FIG. 3 is stored in the file folder 80 of the RAM 26. When receiving the file, create a copy file “File01.pdf” of the document file “File01”, get the time stamp data “TSP.01tsp”, copy the file “File01.pdf” of the file “File01” and the time stamp data “TSP.01tsp” is registered in the file management table 38 in association with each other.

  When the client edits the file, the registered content of the file management table 38 is registered in the history management table 44, and the copy file “File01-up.pdf” of the edited file “File01-up” and the time stamp data are registered. “TSP01-up.tsp” is registered in the file management table 38. As described above, after editing the file, the old information before editing is sequentially stored in the history management table so that the history state can be traced back.

  In the detection of alteration to a file, when alteration to an image file in the file folder 90 is detected, the file name is changed to “File01-er” or the like and managed by the alteration file folder 82 or the like. Since the original file “File01” is restored using the copy file “File01.pdf”, in the embodiment, it is possible not only to detect tampering but also to restore the tampered file. The copy file of the embodiment is stored in the copy file folder 89 of FIG. 4, and the time stamp data is stored in a time stamp data folder not shown.

  FIGS. 4 and 5 show an example of registration processing of the received document file in the file management server 2 in the embodiment. FIGS. 6 and 7 are diagrams for creating an editing history when editing a saved file. An example of processing is shown, and FIGS. 8 and 9 show examples of processing for detecting unauthorized tampering with a saved file and restoring the file. In the embodiment, in the file management server 2, an input folder 84 for storing the document file “File01”, a processing folder 86 for temporarily storing a file when processing a received file or a saved file, and a received document file “ A file folder 80 that saves “File01” and permits access as a shared folder of the client, a copy file folder 89 for storing a copy file, and a time stamp data folder (not shown) are provided.

  In FIG. 4, a document file is received from the personal computer 8 or the like, and the received document file “File01” is stored in the input folder 84. The file management server 2 checks the input folder 84 at predetermined time intervals and the like, and if it detects that a file is stored in the input folder 84, it moves the document file “File01” to the processing folder 86. Copy file creation processing and time stamp data acquisition processing are performed on files in the processing folder 86. The time stamp data is acquired by generating a message digest of the file data and acquiring the time stamp data 90 by the time stamp server 4 or the like. If the file data is pre-assigned with an electronic signature, it is of course possible to add an electronic signature to the file data. Then, the created copy file 88 is associated with the acquired time stamp data 90 and registered in the file management table 38. The document file “File01” is stored in the file folder 80, and the client can access the file folder 80 to perform processing such as file reference and editing. The created copy file 88 is stored in the copy file folder 89.

  FIG. 5 shows processing at the time of file registration in the file management server of the embodiment. When the received document file is stored in the input folder (S1), it is moved to the processing file (S2). Then, a copy file of the document file is created (S3), a hash value of the file data is generated, and time stamp data is acquired (S4). The copy file corresponding to the document file and the time stamp data are registered in the file management table in association with each other (S5), and the received document file is moved to the file folder as a storage file to enable access by the client. (S6).

  A process at the time of editing a saved file will be described with reference to FIG. The client personal computer 8 or the like can access a file stored in the file folder 80 to refer to and edit the file data. When the writing process to the saved file is detected, the file management server 2 moves the file to the processing folder 86 and verifies whether or not the file has been edited using the time stamp data. When it is detected that the file has been edited, the copy file and time stamp data corresponding to the file are moved from the file management table 38 to the history management table 44, and the file editing history is saved.

  For the edited file, a copy file is created in the same manner as when it is received, time stamp data is acquired, and registered in association with the file management table 38. The file management server 2 can manage the copy file and its time stamp data for the file in the latest state, and can also manage the old state data before editing. Even if the file has been edited several times, the history of editing can be saved by registering it in the history management table 44 each time, and the administrator etc. should refer to what kind of editing has occurred at which point. Can do. In the history management table 44, history information is registered by, for example, registering a history for each file in the order of editing time or adding a history number to a file name identifier.

  FIG. 7 shows processing at the time of file editing in the file management server of the embodiment. The connection is established by the connection request from the client (S10), and the client is authenticated using the authentication information set in the file folder in advance for the client requesting access. When the client successfully logs in (S11), the file data is transmitted to the client in response to a read request after login (S13). If the client process is other than writing, the process is performed (S14 to S16). The writing process is performed on the file stored in the file folder, and the target file is temporarily moved to the processing folder (S14, S17). Then, the file is verified with the time stamp data of the file (S18), and editing to the file data is detected. If the hash value of the file data matches the time stamp data, that is, if it has not been edited, the file is returned to the file folder (S19, S20), and the process is terminated.

  On the other hand, when it is detected that the file data has been edited, the copy of the file before editing and the time stamp data are moved from the file management table to the history management table (S19, S21). Then, a copy file of the edited file is created (S22), and time stamp data is generated and acquired (S23), and these are associated and registered in the file management table (S24), and once transferred to the processing folder. The file is returned to the file folder (S25).

  A process for detecting falsification to a saved file and restoring the file will be described with reference to FIG. In the embodiment, whether or not unauthorized editing such as editing by an unauthenticated client has been applied to the saved file with respect to the file in the file folder 80 is performed at a predetermined time interval, for example. In the figure, the file in the file folder 80 is once moved to the processing folder 86, and tampering is verified using the time stamp data. In the embodiment, at the time of regular editing by an authenticated client, the edited file is stored in the file folder 80 and the time stamp data is registered in the file management table 38. That is, in the case of illegal editing / falsification of a file in the file folder 80, the hash value of the file data does not match the time stamp data. When unauthorized editing / tampering is detected, a corresponding copy file is obtained from the file management table 38, and the file is replaced with data before editing, thereby restoring the state before tampering. The altered file is renamed, for example, “File01er” and stored in the altered file folder.

  FIG. 9 shows tampering detection / file restoration processing for a saved file. It is assumed that the alteration of the file in the file folder is periodically monitored every predetermined time, for example, the files in the file folder are sequentially verified or the accessed file is preferentially performed. If there is a file to be verified (S30), it is moved to the processing folder and verified (S31). For the verification, time stamp data obtained from the file management table is used (S32). If the hash value of the file data and the time stamp data do not match, it is determined that the file has been illegally edited / tampered (S33). Is output to a file (S34). Then, the file name “File01” of the altered file is changed to “File01er” or the like, for example, and an identifier is assigned, and the file is stored in the altered file folder (S35). In the embodiment, the file name of the falsified file is changed and saved as a falsification history or the like, but may be discarded. When restoring a falsified file, the corresponding copy file data is obtained from the file management table, and the original file name is given to this and saved in the file folder (S36, S37). Can be accessed.

  As described above, in the embodiment, the received file is stored in the shared folder to manage the file, and the copy file of the stored file is associated with the time stamp data and registered in the file management table. Files can be restored using files.

  Further, when the editing of the saved file by the client is detected, the copy file to be registered in the file management table and the time stamp data are registered in the history management table. Since the edited file creates a copy file each time and obtains time stamp data, the copy file and time stamp data corresponding to the file with the latest contents are registered in the file management table. On the other hand, since old information before editing is managed by moving to the history management table every time editing is performed, the contents and status of the history can be confirmed retrospectively.

In addition, since the verification of the saved file is performed at predetermined intervals using the time stamp data, the originality of the saved file can be more reliably guaranteed. In the embodiment, if the hash value of the data of the storage file does not match the time stamp data, it can be detected that the client has not been authenticated and has been tampered with.

The figure which shows the structure of the file management server of an Example, and the connection with a file management server, a time stamp server, etc. The block diagram which shows the structure of the file management program of the file management server of an Example The figure which shows the outline of the file management in the example The figure which shows the processing at the time of registration of the received file in the example The flowchart which shows the registration processing at the time of the file reception in the file management server of the execution example The figure which shows the process at the time of editing the preservation | save file in an Example The flowchart which shows the process for creating the edit history at the time of the edit to the preservation | save file in the file management server of an Example The figure which shows the process for detecting the alteration to the preservation | save file in an Example, and restoring a preservation | save file The flowchart which shows the detection process of the alteration to the preservation | save file in the file management server of an Example, and the restoration process at the time of alteration

Explanation of symbols

2 File management server 4 Time stamp server 6 LAN
8, 14 Personal computer 10 Router 12 Internet network 20 Main control unit 22 LAN interface 24 Data transmission / reception unit 26 RAM
28 ROM
30 File copy creation unit 32 Message digest generation unit 34 Time stamp data acquisition unit 36 File registration unit 38 File management table 40 Client authentication unit 42 File edit processing unit 44 History management table 46 Time stamp data verification unit 48 Alert information output unit 50 File Restoration processing unit 60 File management program 80 File folder 82 Tampered file folder 84 Input folder 86 Processing folder 88 Copy file 89 Copy file folder 90 Time stamp data

Claims (9)

In the file management server for managing document files on the network,
Receiving means for receiving a document file over a network;
Copy creation means for creating a copy file of the received document file;
Time stamp data acquisition means for acquiring time stamp data in the received document file;
A registration unit for registering the copy file created by the copy creation unit and the time stamp data acquired by the time stamp data acquisition unit in association with each other in a file management table;
The received document file is stored in a shared folder accessible from a client on a network. An edit detection means for detecting whether or not the saved file of the shared folder is edited using the time stamp data is provided,
When it is detected that the saved file is edited, the copy file on the file management table and the time-sump data are registered in the history management table,
A copy file of the edited file is created by the copy creating means, and time stamp data of the edited file is obtained by the time stamp data obtaining means, and the copy file and the time stamp data are obtained. 2. The file management server according to claim 1, wherein the file management server is registered in association with the file management table. Falsification monitoring means for monitoring the presence or absence of falsification of the storage file of the shared folder using the corresponding time stamp data on the file management table;
A tampering information output means for outputting tampering information upon detecting tampering with the saved file;
2. A file repair means for obtaining a copy file of the altered file from the file management table and saving it in the shared folder in place of the altered file. Or the file management server of 2. A file management server program for managing document files on a network,
Instructions for receiving the document file over the network;
Instructions for creating a copy file of the received document file;
A command for obtaining time stamp data in the received document file;
An instruction for associating the created copy file with the acquired time stamp data and registering it in the file management table is provided,
The received document file is stored in a shared folder accessible from a client on a network, and the file management server program. An instruction for detecting the presence or absence of editing of the saved file of the shared folder using the time stamp data;
An instruction for registering the copy file and time-sump data on the file management table in the history management table when detecting that the saved file is edited;
Instructions for creating a copy file of the edited file;
Instructions for obtaining timestamp data of the edited file;
5. The file management server program according to claim 4, further comprising: an instruction for associating these copy files with time stamp data and registering them in the file management table. Instructions for monitoring the presence or absence of falsification of the storage file of the shared folder using the corresponding time stamp data on the file management table;
A command for outputting falsification information upon detection of falsification to the saved file;
An instruction for obtaining a copy file of the altered file from the file management table;
6. The file management server program according to claim 4, further comprising: an instruction for saving the obtained copy file in the shared folder in place of the altered file. A method for managing a document file on a network using a file management server,
Steps for receiving a document file over a network;
Creating a copy file of the received document file;
Obtaining time stamp data in the received document file;
A step for associating the copy file with the time stamp data and registering it in a file management table;
The received document file is stored in a shared folder accessible from a client on a network, and the file management method of the file management server is characterized in that: A step for detecting the presence or absence of editing of the storage file of the shared folder using the time stamp data;
A step for registering the copy file on the file management table and time-sampling data in the history management table when detecting that the saved file is edited;
Creating a copy file of the edited file;
Obtaining time stamp data of the edited file;
8. The file management method according to claim 7, further comprising: a step of associating these copy files with time stamp data and registering them in the file management table. Monitoring the presence or absence of falsification of the shared folder to the saved file using corresponding time stamp data on the file management table;
Detecting tampering with the saved file, outputting tampering information;
Obtaining a copy file of the altered file from the file management table;
9. The file management method according to claim 7, further comprising: a step for saving the obtained copy file in the shared folder in place of the altered file.

Images