JP2008123049A - Automatic file decryption and encryption system, its method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To normally protect a file even when the file is moved due to the fault of a user by automatically decrypting or encrypting the file without neither deteriorating convenience in user nor specifying the type of the file and a program to be used. <P>SOLUTION: The automatic file decryption and encryption system includes: a capsule file generating means 0401 for converting the file existing in a computer into a capsule file; and the capsule file 0402 for protecting the file by enclosing the encrypted file. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention automatically encrypts a file created on a computer, automatically decrypts the file when the user views and edits, and automatically encrypts the file again when the user finishes viewing and editing. Related to technology.

  As technologies for encrypting and protecting files, there are the following three technologies.

  First, the first technique is a program for designating a file to be protected by a user and outputting an encrypted file using the file as an input (hereinafter referred to as conventional technique 1). Prior art 1 is a method adopted in many encryption programs, and a user can easily encrypt a file to be protected. Further, in the prior art 1, when the user decrypts, the decrypted file is output by executing the program with the file to be encrypted as an input.

  The second technology is an encryption system that operates in the file system layer of the operating system (hereinafter referred to as Conventional Technology 2). As a typical example of the prior art 2, there is an EFS (Encrypted File System) manufactured by Microsoft (registered trademark). The prior art 2 is a technique for automatically encrypting a file when writing the file and decrypting the file when reading the file by incorporating file encryption / decryption into the file system layer of the operating system. Thus, the user does not need to perform a special operation for file encryption / decryption, and can protect the file while performing the same file operation as usual.

  The third technique is DRM (Digital Rights Management) (hereinafter referred to as Conventional Technique 3). As a representative example of the prior art 3, there is MS-RMS (Microsoft Rights Management Service) of Microsoft (registered trademark). In the prior art 3, a user who can encrypt / decrypt a file is managed by an authentication server, and when the user views and edits the file, the program that reads the file decrypts the file by the user who started the program Check with the authentication server whether the user is authorized, and if the user is authorized, automatically decrypt the file. Also, when the user finishes viewing and editing the file, the file is automatically encrypted.

Here, in the encapsulated document, content information, an operation program for realizing various functions by the computer, and transmission destination information for transmitting various information to the computer are encapsulated as a single document. There has been proposed a technique capable of preventing unauthorized use of content information in an encapsulated document file and protecting the copyright of the content information by restricting the operation processing for the content information in the file ( For example, see Patent Document 1).
Japanese Patent Laying-Open No. 2005-092709

  However, when the prior art 1 is used, there are the following problems. When a user browses and edits a file encrypted by the conventional method 1, the user must browse and edit the file after explicitly decrypting the encrypted file, and then the user needs to encrypt the file again. There is. For this reason, while viewing and editing a file, the file is unencrypted and unprotected. In addition, the usage method when the file is encrypted usually significantly impairs the convenience of the user as compared to the usage method when the file is not encrypted. Therefore, after the user finishes viewing and editing the file, there may be a problem that the file is not protected because the user forgets to encrypt the file. For the above reason, the file cannot always be protected by the prior art 1.

  In contrast to this problem, the conventional technique 2 can solve the problems of the conventional technique 1. However, the file can be protected by the prior art 2 only when a third party tries to read the file when the medium on which the file is recorded is stolen or lost. When a user accidentally attaches a protected file to an e-mail and transmits the file, the conventional technology 2 cannot protect the file because the protected file is attached in a decrypted state.

  Prior art 3 can solve the problems of prior art 1 and prior art 2. However, in the prior art 3, the program itself used for editing and browsing the file must correspond to the prior art 3. Also in the case of MS-RMS, a program that can be used at the time of browsing and editing a file is limited to only Microsoft Office 2003 (registered trademark), and a file type that can be protected is also limited to a file that can be handled by Microsoft Office 2003 (registered trademark). Therefore, a file of a type that is not supported by the conventional technique 3 cannot be protected. In addition, when a file must be sent to an organization using a DRM system other than MS-RMS, it is necessary to decrypt and send the file once, so that the file cannot always be protected.

  In the above-described conventional technology, when it is desired to permit browsing of a file with a limited period or number of times, the user needs to manually change the viewing and editing authority of the file as necessary. In that case, the file cannot be protected if the user forgets to change it due to negligence.

  The present invention has been made to solve the above-described problems. Its purpose is to automatically decrypt and encrypt the file without specifying the file type or the program to be used without losing the convenience of the user, and always protecting the file even when it is moved due to the user's fault Is to be able to do it.

  In order to solve the above-described problem, a file automatic decryption / encryption system according to the present invention operates in a computer 01 on which an operating system 02 operates, and generates a capsule file that converts a file 03 existing in the computer 01 into a capsule file 0402. Means 0401 is provided.

  The capsule file generation unit 0401 is encrypted by the file encryption unit 040101 for encrypting the file 03, the user authority information setting unit 040102 for generating the user authority information 040202 for the user who is permitted to view and edit the file 03, and the file encryption unit 040101. And an executable file generation unit 040103 for generating a capsule file 0402 by combining the converted file 03 and the user authority information 040202 generated by the user authority information setting unit 040102.

  The capsule file 0402 is generated as an executable file executable on the computer 01 by the capsule file generation unit 0401. The capsule file 0402 is a part of the automatic file decryption encryption system, but can be executed alone, and can be copied and moved within the computer or between computers via the network by the capsule file 0402 alone. Features.

  The capsule file 0402 includes a first automatic decryption encryption unit 040201, user authority information 040202 in which information related to a user who is permitted to view and edit the capsule file 0402, and a file 03 encrypted by the file encryption unit 040101. Further, it is characterized in that it includes a file 03 included in the capsule file 0402 and capsule configuration information 040203 in which information related to user authority information is recorded.

  The first automatic decryption encryption unit 040201 is automatically activated when the user executes the capsule file 0402. The automatic decryption encryption unit 040201 includes a file extraction unit 04020101 that extracts the file 03 included in the capsule file 0402, a file decryption unit 04020102 that decrypts the encrypted data of the file 03 extracted by the file extraction unit 04020101, and a decryption Editing program starting means 04020103 for starting the editing program 05 for viewing and editing the data in the file 03, editing program monitoring means 04020104 for monitoring the started editing program 05, and when the user finishes editing the file 03 The file re-encryption unit 04020105 for re-encrypting the data of the file 03 edited by the user, and the data of the file 03 encrypted by the file re-encryption unit 04020105 is again the capsule file 0. Characterized in that it has a file storage unit 04020106 for storing 02.

  The capsule file 0402 is characterized in that the user can view and edit the capsule file 0402 by the same method as the operation method for viewing and editing the normal file 03.

  When the user executes an operation method for browsing or editing the capsule file 0402, the first automatic decryption encryption unit 040201 is automatically activated, and the first automatic decryption encryption unit 040201 is included in the capsule file 0402. 03 is automatically decrypted, the information of the editing program 05 associated with the file 03 is acquired from the operating system 02, and the editing program 05 is started so that the user can view and edit the decrypted file 03. Features.

The first automatic decryption / encryption means 040201 monitors the activated editing program 05 so that the data in the file 03 is not leaked to files other than the file 03 or other editing programs editing the file other than the file 03. It can be prohibited.
The first automatic decryption encryption unit 040201 detects the end of the editing program 05 by monitoring the started editing program 05, re-encrypts the changed file 03, and stores it in the capsule file 0402. To do.

  When the capsule file 0402 is executed by a user who is not recorded in the user authority information 040202 included in the capsule file 0402, browsing and editing of the capsule file 0402 can be prohibited by the first automatic decryption encryption unit 040201. When the capsule file 0402 is executed by the user recorded in the user authority information 040202 included in the capsule file 0402, the first automatic decryption encryption unit 040201 requests a password from the user, and the password is When the password does not match the password recorded in the authority information 040202, the first automatic decryption / encryption means 040201 can prohibit browsing and editing of the capsule file 0402.

  The file automatic decryption / encryption system of the present invention permits browsing and editing of the capsule file 0402, for example, by adding time limit information that allows the capsule file 0402 to be edited to the user authority information 040202 included in the capsule file 0402. Even if the user has been executed, when the capsule file 0402 is executed after the expiration date, the user has expiration date determination type file extraction means 04020107 for prohibiting browsing and editing.

  Similarly, instead of the file decryption unit 04020102, by adding the number of times the capsule file 0402 can be viewed and edited to the user authority information 040202 included in the capsule file 0402, the view and edit of the capsule file 0402 is permitted. Even when the user has been executed, when the capsule file 0402 is executed more than the number of times recorded in the user authority information 040202, it has a number-of-times determination formula file extraction unit 04020208 that prohibits browsing and editing.

  The file automatic decryption / encryption system of the present invention, when transmitting the file 03 to a user who already uses a system such as the prior art 3, takes the capsule file 0402 as an input and uses the file of the format used in the prior art 3 By having the export unit 0403 that converts and outputs the file 03, it is possible to transmit the file 03 to the user using the conventional technique 3 without reducing the security strength of the file.

  Similarly, when the file 03 is received from a user who already uses a system such as the prior art 3, an import unit that takes a file in the format used in the prior art 3 as an input, converts the file into a capsule file 0402, and outputs it. By having 0404, the file 03 can be received from the user using the conventional technique 3 without reducing the security strength of the file.

  According to the present invention, the file is automatically decrypted and encrypted without specifying the file type and the program to be used without losing the convenience of the user, and the file can be moved even when the file is moved due to the user's negligence. You will be able to always protect.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the common part in each figure.

  First, referring to FIG. 1, the first embodiment of the present invention includes an operating system 02, a file 03, a file automatic decryption encryption system 04, and an editing program 05 on a computer 01. The automatic file decryption / encryption system 04 includes a capsule file generation unit 0401 and a capsule file 0402. The capsule file generation unit 0401 includes a file encryption unit 040101, a user authority information setting unit 040102, and an execution file generation unit 040103. The capsule file 0402 includes a first automatic decryption encryption unit 040201, a file 03 encrypted by the first automatic decryption encryption unit 040201, user authority information 040202, and capsule configuration information 040203.

  The computer 01 is a personal computer, workstation, server, large computer, or other information processing apparatus capable of inputting, editing, and displaying document data.

  The operating system 02 is Microsoft (registered trademark) Windows (registered trademark) or Linux.

  The editing program 05 is application software that operates on the computer 01 and has a file browsing function and an editing function. For example, notepad (registered trademark) which is a text file editor attached to Microsoft Windows (registered trademark) standard, application software represented by Microsoft Word (registered trademark), Excel (registered trademark), etc. .

  The file 03 to be edited by the editing program 05 is any file handled by the editing program such as a text file, an image file, and a binary file. The file 03 to be edited by the editing program 05 may be a file existing in the computer 01 or a file existing in another computer connected to the network.

  The file browsing function is a function for reading file data and displaying file data. The file editing function is a function for adding, changing, and deleting file data, and saving the file again.

  The capsule file generation unit 0401 generates a capsule file 0402 when a file 03 to be protected is designated by the user. After creating the capsule file 0402, the capsule file generation unit 0401 completely deletes the file 03 so that the file 03 is not restored.

  The file encryption unit 040101 encrypts the file 03 specified by the user.

  The file encryption unit 040101 may encrypt the file 03 with any encryption algorithm. The present invention will be described on the assumption that a common key method using the same key for encryption and decryption is used and the key is stored in the capsule file. However, a method that cooperates with an external user authentication server or an RSA cipher The security strength can be increased by adopting a publicly known public key cryptosystem.

  The user authority information setting unit 040102 generates user authority information 040202, which is information relating to a user who can view or edit the encrypted file 03.

  The configuration of the user authority information 040202 is shown in FIG.

  T04020201 (user ID): A user ID permitted to access is set.

  T04020202 (access authority): Sets whether or not there is a read / write authority for the file 03. If there is no writing authority, writing to the file 03 is prohibited by prohibiting file writing in the editing program monitoring means 0402020, which will be described later.

  T04020203 (user authentication password): Stores a password for identifying a user who is permitted to view or edit the capsule file 0402. When the user tries to view or edit the capsule file 0402, the first automatic decryption encryption means 040201 requests a password from the user, and if the entered password does not match the one recorded in this field, Do not allow editing.

  Addition, deletion, and change of users permitted to view and edit the capsule file 0402 are executed when the capsule file generation unit 0401 creates the capsule file 0402. In the present invention, the user authority information 040202 recorded in the capsule file 0402 is encrypted to protect this information itself.

  In the user authority information 040202, T04020201, T04020202, and T04020203 are combined into one record, and records are stored as many as the number of users specified by the user who created the capsule file 0402.

  Even if the capsule file 0402 is a user who is permitted to view and edit the capsule file 0402 by adding time limit information that allows the capsule file 0402 to be edited to the user authority information 040202 included in the capsule file 0402. Even if the capsule file 0402 is executed after the expiration date, browsing and editing of the capsule file 0402 can be prohibited. Similarly, the capsule file 0402 adds the number of times the capsule file 0402 can be viewed and edited to the user authority information 040202, so that even if the user is permitted to view and edit the capsule file 0402, the user authority information 040202 Even if the capsule file 0402 is executed more than the number of times recorded in, the browsing and editing can be prohibited.

  The executable file generation unit 040103 stores the file 03 encrypted by the file encryption unit 040101 and the user authority information 040202 generated by the user authority information setting unit 040102 in the capsule file 0402. The execution file generation unit 040103 generates the capsule file 0402 as a single executable file by storing the automatic decryption encryption unit 040201 at the head of the capsule file 0402.

  The execution file generation unit 040103 generates capsule configuration information 040203 indicating the positions of the file 03 and the user authority information 040202 in the capsule file 0402, and adds it to the end of the capsule file 0402. The configuration of the capsule configuration information 040203 is shown in FIG.

T04020301 (capsule configuration information size): Stores the size of the capsule configuration information 040203 itself.
T04020302 (user authority information size): The size of the user authority information 040202 is stored.
T04020303 (file size): Stores the size of the file 03 included in the capsule file 0402.
T04020304 (file name): The file name of the file 03 is stored.

  T04020305 (encrypted password): Stores a password used when the file 03 is encrypted or decrypted.

  Information set in the capsule configuration information size T04020301 is always arranged at the end of the capsule file 0402. The first automatic decryption encryption unit 040201 can read the capsule configuration information 040203 by obtaining the size of the capsule configuration information from the tail end of the capsule file 0402.

  The capsule file 0402 allows the user to view and edit the capsule file 0402 in the same manner as the operation method for viewing and editing the normal file 03.

  The capsule file 0402 is a part of the file automatic decryption / encryption system 04, but can be executed alone on the computer 01 or another computer connected via the network. The capsule file 0402 can be copied and moved to the computer 01 or another computer connected via the network.

  When the user executes an operation method for browsing or editing the capsule file 0402, the first automatic decryption encryption unit 040201 is automatically activated. The first automatic decryption / encryption means 040201 can automatically decrypt the file 03 included in the capsule file 0402, and can view and edit the file 03.

  The first automatic decryption encryption unit 040201 will be described in detail with reference to FIG. Referring to FIG. 4, the first automatic decryption / encryption means 040201 is composed of a file extraction means 04020101, a file decryption means 04020102, an edit program starting means 04020203, an edit program monitoring means 04020204, a file re-encryption means 04020205, and a file storage means 04020206. Yes.

  The file extraction unit 04020101 performs user authentication using the user authority information 040202 recorded in the capsule file 0402 and the user information executing the capsule file 0402, and is a user who has authority to view and edit the capsule file 0402. For example, the capsule configuration information 040203 recorded at the end of the capsule file 0402 is read, and the data of the file 03 included in the capsule file 0402 is extracted. In the present invention, the user authentication method is described on the premise that the authentication is based on the user name and the password. However, the user authentication method may be a password authentication method or a directory authentication method using LDAP or the like. The user authority information 040202 may store data necessary for user authentication.

  The file decryption unit 04020102 decrypts the file 03 taken out by the file extraction unit 04020101 and stores it in the temporary file 06 (FIG. 7). The temporary file 06 is protected by the file decryption unit 04020102 so that it cannot be accessed by other users or programs. The user file decryption unit 04020102 protects the temporary file 06 using a file access exclusive control function provided by the operating system 02.

  The editing program starting unit 04020203 starts the editing program 05 for editing the temporary file 06 decrypted by the file decrypting unit 04020102. In a widely known operating system such as Microsoft (registered trademark) Windows (registered trademark), the file type is classified by file format, extension, etc., each classified file type and a program that can edit the file type Manages information associated with. The editing program starting unit 04020203 acquires this information from the operating system 02, acquires information of the editing program 05 associated with the file 03, and starts the editing program 05.

  The editing program monitoring unit 04020104 monitors the editing program 05 started by the program starting unit 04020203, and detects the end of execution of the editing program 05, the end of editing, file reading and file writing.

  The editing program 05 requests the operating system 02 to read data from the file or write data to the file when browsing or editing the file.

  A well-known operating system such as Windows (registered trademark) of Microsoft Corporation generates an event when a request is received from a program such as the editing program 05. When the program issues a data read request from a file to the operating system, the operating system generates a file data read event. In a well-known operating system such as Windows (registered trademark), an event interception method described in Reference 1 is used, that is, a intercepting means for causing an event other than a program that has generated an event to intercept these events. (Application Programming Interface). Using this function, the editing program monitoring means 04020104 intercepts event information 07 generated by the editing program 05 for the operating system 02 using the preemption means 0201 in the operating system 02. ([Reference] Jeffrey Richter, Stock ASCII, "Advanced Windows revised 4th edition" pp.673-814)

  FIG. 8 shows a mechanism in which the editing program monitoring unit 04020104 intercepts the event information 07 generated by the editing program 05. The editing program monitoring means 04020104 that intercepted the event information 07 executes the intercepting means 0201 so as to return the control to the operating system 02 without interrupting the event information 07, thereby preventing the event information 07 from interfering with the processing of the editing program 05. It becomes possible to get. The type of event information 07 includes file read event information that occurs when a file is read and file write event information that occurs when a file is written. Further, by blocking the event information 07 without notifying the operating system 02, it is possible to prohibit data reading from the file and data writing to the file. FIG. 9 shows the configuration of the event information 07 acquired by the program monitoring unit 04020104.

  T0701 (event type): represents an event type. Read or write is set.

  T0702 (file name): represents the name of the file to be read or written.

  The file re-encryption unit 04020105 encrypts the edited data of the temporary file 06 when the program monitoring unit 04020104 detects the end of editing or the end of execution of the editing program 05.

  The file storage unit 04020206 records the data encrypted by the file re-encryption unit 04020205 again in the capsule file 0402, cancels the protection of the temporary file 06 protected by the file decryption unit 04020102, and deletes the temporary file 06.

  When the first invention has the above configuration, the file 03 can be protected by encrypting and encapsulating the file 03 in the capsule file 0402.

  In the description of the operation, this processing flow will be described using a flowchart. (Fig. 10)

  Next, the operation of the present embodiment will be described in detail with reference to the flowchart with reference to FIG.

  Step S01: A step in which the user executes the capsule file generation unit 0401 to generate a capsule file 0402. The capsule file generation unit 0401 reads the file 03 designated by the user and creates a capsule file 0402. When the creation of the capsule file 0402 is completed, the process proceeds to step S02. This step is a process executed in the capsule file generation unit 0401, and the flow of the process will be described later with reference to FIG.

  Step S02: A step in which the user executes the capsule file 0402 created by the capsule file generation means 0401. When the user executes the capsule file 0402, the first automatic decryption / encryption means 040201 is automatically activated and the process proceeds to step S03.

  Step S03: The first automatic decryption / encryption means 040201 authenticates the user and confirms the authority. This step is a process executed in the first automatic decryption / encryption means 040201, and the flow of the process will be described later with reference to FIG.

  Step S04: A step of allocating processing according to the result of step S03. If the user does not have access authority as a result of user authentication, the process ends. If the user has access authority, the process proceeds to step S05.

  Step S05: The editing application 05 is activated and starts editing the file 03. This step is a process executed in the first automatic decryption encryption unit 040201, and the flow of the process will be described later with reference to FIG.

  Step S06: A step of ending the editing application 05 and ending editing of the file 03. This step is a process executed in the first automatic decryption encryption unit 040201, and the flow of the process will be described later with reference to FIG.

  Details of step S01 will be described below with reference to FIG.

  Step S0101: A step in which the user specifies the file 03 to be protected and executes the capsule file generation unit 0401. When the capsule file generating unit 0401 is activated, the process proceeds to step S0102.

  Step S0102: The execution file generating means 040103 creates a capsule file 0401 and stores the first automatic decryption encryption means 040201 at the head. The execution file generation unit 040103 determines the file name of the capsule file 0402 based on the file name of the file 03 specified by the user, and creates an empty capsule file 0402 with that name. Then, first automatic decryption encryption means 040201 is stored at the head of the file. When the storage is completed, the process proceeds to step S0103.

  Step S0103: A step of requesting the user a password to be used as a key when the file encryption means 040102 encrypts. When the password is input from the user, the file encryption unit 040102 stores the password in the temporary area, and proceeds to step S0104.

  Step S0104: The file encryption unit 040102 encrypts the file 03 and stores it in a temporary file. The file encryption 040102 encrypts the data in the file 03 using the password stored in the temporary area in step S0103, and writes the data in the temporary file. When the encryption of the file 03 is completed, the process proceeds to step S0105.

  Step S0105: The file encryption unit 040102 adds a temporary file to the capsule file 0402. The file encryption unit 040102 adds the temporary file data created in step S0104 to the end of the capsule file 0402, and proceeds to step S0106.

  Step S0106: The user authority information setting unit 040102 creates user authority information 040202 and adds it to the capsule file 0402. The user authority information setting unit 040102 allows the user to designate a user who is permitted to view or edit the capsule file 0402. The user designates a user ID for giving authority, a user authentication password, and an access authority (reading and writing) to be added to the designated user. When the user finishes specifying, the user authority information setting unit 040102 creates user authority information 040202 in the temporary area, sets the user ID specified by the user in the user ID field T04020201 of the user authority information 040202, and the access authority specified by the user. Is set in the access authority field T04020202, and the user authentication password designated by the user is set in the user authentication password field T04020203. When the user authority information setting unit 040102 completes the creation of the user authority information 040202, the user authority information 040202 created in the temporary area is added to the capsule file 0402. When the user authority information setting unit 040102 completes the addition of the user authority information 040202, the process proceeds to step S0107.

  Step S0107: The execution file generating means 040103 creates capsule configuration information 040203 and adds it to the capsule file 0402. The execution file generating unit 040103 generates capsule configuration information 040203 in the temporary area. The execution file generation unit 040103 sets the size of the user authority information 040202 added to the capsule file 0402 by the user authority information setting unit 040102 in the user authority information size field T04020302 of the capsule configuration information 040203, and the file encryption unit 040101 sets the capsule file 0402. Is set in the file size field T04020303, the file name of the file 03 is set in the file name field T04020304, and the password used by the file encryption unit 040101 for encryption of the file 03 is set in the password field T04020305. Set. Then, the size of the capsule configuration information 040203 is set in the capsule configuration information size field T04020301, and the capsule configuration information 040203 is added to the end of the capsule file 0402.

  When the execution file generating unit 040103 completes the addition of the capsule configuration information 040203 at the end of the capsule file 0402, the process proceeds to step S0108.

  Step S0108: The file encryption unit 040101 deletes the temporary file and the file 03. When the file encryption unit 040101 has confirmed that the capsule file 0402 has been created normally, the file encryption unit 040101 deletes the temporary file and the file 03 created in step S0104.

  Hereinafter, details of step S03 will be described with reference to FIG.

  Step S0301: Step in which the file extraction unit 04020101 acquires the capsule configuration information size T04020301 from the capsule file 0402. The file extraction unit 04020201 reads the capsule configuration information size T04020301 recorded at a fixed length at the end of the capsule file 0402, and proceeds to step S0302.

  Step S0302: A step in which the file extraction unit 04020201 acquires the capsule configuration information 040203 from the capsule file 0402. Using the capsule configuration information size T04020301 acquired in step S0301, the file extraction unit 04020201 reads the capsule configuration information 040203 for the size indicated by the capsule configuration information size T04020301 from the end of the capsule file 0402, and proceeds to step S0303.

  Step S0303: A step in which the file extraction unit 04020201 obtains user authority information 040202 from the capsule file 0402. The file extraction unit 04020201 acquires the user authority information size T04020301 from the capsule configuration information 040203, and calculates the offset to the user authority information 040202 by adding the capsule configuration information size T04020301 acquired in step S0301. Then, the file extraction unit 04020201 reads the user authority information 040202 from the capsule file 0402 using the calculated offset, and proceeds to step S0304.

  Step S0304: A step in which the file extraction unit 04020101 searches the user authority information 040202 to acquire the authority given to the current user. The file extraction unit 04020101 acquires the user ID of the user who is currently executing the capsule file 0402. Further, the file extraction unit 04020101 requests the user for a password for identifying the user. Then, the user authority information 040202 holds the same user ID in the user ID field T04020201 and searches for a record holding the password acquired from the user in the password field T04020203. If there is a record, the process proceeds to step S0305.

  Step S0305: A step of branching the process using the search result in step S0304. If the file extraction unit 04020201 finds a record in which the user ID of the user who is currently executing the capsule file 0402 is registered in the user ID field T04020201 in the user authority information 040202 in step S0304, the process proceeds to step S0306. If not registered, the process ends.

  Step S0306: A step in which the file extracting means 04020101 acquires access authority. The file extraction unit 04020201 refers to the access authority field T04020202 of the record found in the user authority information 040202, determines whether or not there is an access authority to the capsule file 0402, and stores the result in a temporary area.

  Details of step S05 will be described below with reference to FIG.

  Step S0501: Step in which the file extraction unit 04020101 creates a temporary folder. The file extraction unit 04020201 creates a temporary folder for expanding the file 03 included in the capsule file 0402. When the creation of the temporary folder is completed, the process proceeds to step S0502.

  Step S0502: A step in which the file extraction unit 04020101 extracts the encrypted file 03 from the capsule file 0402 and stores it in the temporary folder as the temporary file 06. The file extraction unit 04020201 reads the capsule configuration information 040203 from the capsule file 0402 and records it in the temporary area. The file extraction unit 04020201 calculates an offset value from the capsule configuration information size field T04020301, the user authority information size field T04020302, and the file size field T04020303 of the capsule configuration information 040203 to the storage portion of the file 03. Further, the file extraction unit 04020201 acquires the file name of the file 03 from the file name field T04020304 of the capsule configuration information 040203, acquires the encryption password obtained by encrypting the file 03 from the encryption password field T04020305 of the capsule configuration information 040203, and temporarily stores them. Record in the area. The file extraction unit 04020201 reads the data of the file 03 encrypted using the calculated offset value, and stores it as a temporary file 06. When the file extraction unit 04020201 completes saving of the temporary file 06, the process proceeds to step S0503.

  Step S0503: A step in which the file decryption means 04020102 decrypts the temporary file. The file decryption unit 04020102 decrypts the temporary file 06 using the encryption password recorded in the temporary area by the file extraction unit 04020101 in step S0502, and proceeds to step S0504.

  Step S0504: A step in which the program starting means 04020103 acquires the file name of the editing program 05 corresponding to the file 03. The program activation unit 04020203 acquires the file name of the editing program 05 associated with the file 03 from the operating system 02 using the file name of the file 03 recorded in the temporary area by the file extraction unit 04020101 in step S0502. Then, the program activation unit 04020103 records the acquired file name in the temporary area, and proceeds to step S0505.

  Step S0505: A step in which the program starting means 04020103 starts the editing program 05. The program starting unit 04020203 starts the editing program 05 using the file name recorded in the temporary area in step S0504, and proceeds to step S0506.

  Step S0506: The program monitoring means 04020104 starts monitoring the editing program 05. The program monitoring unit 04020104 monitors whether the editing program is executed and file access (file reading and file writing) of the editing program 05.

  Details of step S06 will be described below with reference to FIG.

  Step S0601: A step in which the user ends the editing program 05 and the program monitoring means 0402020 detects the end of the editing program 05. When the user operates the editing program and ends the editing program 05, the program monitoring unit 04020104 detects that the editing program 05 has ended, and the process proceeds to step S0602.

  Step S0602: A step in which the file re-encryption means 04020105 encrypts the temporary file 06. The file re-encryption means 04020105 encrypts the temporary file that has been edited by the editing program 05 using the encryption password recorded in the temporary area by the file extraction means 04020101 in step S0502, and proceeds to step S0603.

  Step S0603: A step in which the file storage means 04020206 stores the temporary file in the capsule file 0402. The file storage unit 04020106 replaces the data of the old file 03 in the capsule file 0402 with the data of the temporary file 06, and proceeds to step S0604.

  Step S0604: The file storage unit 04020206 updates the capsule information and stores it in the capsule file 0402. The file storage unit 04020206 updates the file size field T04020303 of the capsule configuration information 040203 recorded in the temporary area in step S0502 to the size of the temporary file replaced in step S0603, and updates the old capsule configuration information 040203 of the capsule file 0402. Replace with the capsule configuration information 040203 of the area. When the replacement is completed, the process proceeds to step S0605.

  Step S0605: a step in which the file storage unit 04020206 deletes the temporary file 06 and the temporary folder. The file storage unit 04020106 releases the protection of the temporary file 06 and deletes it.

  As described above, the file 03 generated on the computer 01 is encrypted, and the file 03 is automatically decrypted when viewed and edited while the editing program 05 normally used by the user is used as it is. When you finish, you can automatically encrypt the file.

Next, a second embodiment of the present invention will be described in detail with reference to FIG.
This embodiment has the same configuration as that of the first embodiment except that the second automatic decryption encryption unit 040204 is provided instead of the first automatic decryption encryption unit 040201. In the user authority information 040202 and the file extracting unit 04020201, even if the user is permitted to view and edit the capsule file 0402 by adding the time limit information T04020204 that allows the capsule file 0402 to be viewed and edited in the user authority information 040202. When the time limit has been exceeded, a time limit judgment type file extraction unit 04020107 for prohibiting the data extraction of the file 03 included in the capsule file 0402 is provided and replaced with the file extraction unit 04020101. Viewing and editing can be prohibited. FIG. 24 shows an example of the user authority information 040202 when the term information T04020204 is added. Further, FIG. 25 shows the configuration of the second automatic decryption encryption means 040204 in which the file extraction means 04020201 is replaced with the expiration date judgment expression file extraction means 0402020.

  When the present embodiment has the above-described configuration, browsing and editing of the capsule file 0402 that has expired can be prohibited.

  Next, the operation of the present embodiment will be described with reference to a flowchart. The operation of the present embodiment replaces the following steps in the operation of the first embodiment.

  First, step S0106 shown in FIG. 11 is replaced as follows. Step S0106: The user authority information setting means 040102 creates user authority information 040202 and adds it to the capsule file 0402. The user authority information setting unit 040102 allows the user to designate a user who is permitted to view or edit the capsule file 0402. The user designates a user ID for giving authority, a user authentication password, and an access authority (reading and writing) to be added to the designated user. When the user finishes specifying, the user authority information setting unit 040102 creates user authority information 040202 in the temporary area, sets the user ID specified by the user in the user ID field T04020201 of the user authority information 040202, and the access authority specified by the user. Is set in the access authority field T04020202, the user authentication password specified by the user is set in the user authentication password field T04020203, and the time limit information specified by the user is set in the time limit information field T04020204. The term information is an upper limit value for limiting the date on which the user can view and edit the capsule file 0402. When the user authority information setting unit 040102 completes the creation of the user authority information 040202, the user authority information 040202 created in the temporary area is added to the capsule file 0402. When the user authority information setting unit 040102 completes the addition of the user authority information 040202, the process proceeds to step S0107.

  Next, step S0304 shown in FIG. 12 is replaced as follows. Step S0304: A step in which the time limit judgment formula file extraction unit 0402020 searches the user authority information 040202 to acquire the authority given to the current user. The expiration date determination expression file extraction unit 04020107 acquires the user ID of the user who is currently executing the capsule file 0402. Further, the term determination formula file extraction unit 04020107 requests the user for a password for identifying the user. In the user authority information 040202, the same user ID is held in the user ID field T04020201 and a search is made for a record holding the password acquired from the user in the password field T04020203. If there is a record, the expiration date information field T04020204 is searched. Compare the deadline information held with the current date. If the current date has not passed the date set in the deadline information, the process proceeds to step S0305.

  As described above, by setting time limit information when the user views and edits the file 03, it is possible to automatically limit browsing and editing of files whose time limit has passed.

Next, a third embodiment of the present invention will be described in detail with reference to FIG.
This embodiment has the same configuration except that the third automatic decryption encryption unit 040204 is provided instead of the first automatic decryption encryption unit 040201. In the user authority information 040202 and the file extracting unit 04020201, even if the user is permitted to view and edit the capsule file 0402 by adding the number-of-times information T04020205 that allows the capsule file 0402 to be viewed and edited in the user authority information 040202. When the number of times has exceeded, the number-of-times-determining expression file extraction unit 0402020 that prohibits the data extraction of the file 03 contained in the capsule file 0402 is provided and replaced with the file extraction unit 04020101, thereby allowing the capsule file 0402 whose time limit has passed. Viewing and editing can be prohibited. FIG. 26 shows an example of user authority information 040202 when the number information T04020205 is added. FIG. 27 shows the configuration of the third automatic decryption / encryption means 040205 in which the file extraction means 04020201 is replaced with the frequency determination formula file extraction means 04020208.

  When the present embodiment has the above-described configuration, browsing and editing of the capsule file 0402 more than the permitted number of times can be prohibited.

  Next, the operation of the embodiment for implementing the third invention will be described with reference to a flowchart. The operation of the present embodiment replaces the following steps in the operation of the first embodiment.

  First, step S0106 shown in FIG. 11 is replaced as follows. Step S0106: The user authority information setting unit 040102 creates user authority information 040202 and adds it to the capsule file 0402. The user authority information setting unit 040102 allows the user to designate a user who is permitted to view or edit the capsule file 0402. The user designates a user ID for giving authority, a user authentication password, and an access authority (reading and writing) to be added to the designated user. When the user finishes specifying, the user authority information setting unit 040102 creates user authority information 040202 in the temporary area, sets the user ID specified by the user in the user ID field T04020201 of the user authority information 040202, and the access authority specified by the user. Is set in the access authority field T0402022, the user authentication password specified by the user is set in the user authentication password field T04020203, and the number of times information specified by the user is set in the number of times information field T04020205. The frequency information is an upper limit value for limiting the number of times that the user can view and edit the capsule file 0402. When the user authority information setting unit 040102 completes the creation of the user authority information 040202, the user authority information 040202 created in the temporary area is added to the capsule file 0402. When the user authority information setting unit 040102 completes the addition of the user authority information 040202, the process proceeds to step S0107.

  Next, step S0304 shown in FIG. 12 is replaced as follows. Step S0304: A step in which the number-of-times determination formula file extraction unit 0402020 retrieves the user authority information 040202 to acquire the authority given to the current user. The number determination expression file extraction unit 04020208 acquires the user ID of the user who is currently executing the capsule file 0402. Further, the number determination formula file extraction unit 04020208 requests a password for identifying the user from the user. In the user authority information 040202, the same user ID is held in the user ID field T04020201, and a search is made for a record holding the password acquired from the user in the password field T04020203. If there is a record, the number information field T04020204 is searched. The held number information is confirmed, and the number information is subtracted by one. However, when the frequency information is a value indicating unlimited, the frequency information is not subtracted. As a result of subtracting the number information, if the number information is 0 or more or a value indicating unlimited, the process proceeds to step S0305.

  As described above, by setting the number of times information when the user views and edits the file 03, it is possible to automatically limit the viewing and editing of the file after the permitted number of times.

  Next, a fourth embodiment of the present invention will be described in detail with reference to FIG.

When the present invention is used in combination with an existing DRM system 09 such as the prior art 3, it is provided with an export means 0403 for converting the file format used in the prior art into a capsule file 0402, thereby providing a safe file for the environment in which the prior art is operated. Enable transfer. When the fourth invention has the above configuration, the file can be safely transmitted to another organization operating the existing DRM system 09 while maintaining the file protection state.
Next, the operation of the fourth embodiment will be described with reference to the flowchart shown in FIG.

  Step S0701: The export unit 0403 obtains export destination user information from the user.

  Step S0702: The export unit 0403 extracts the encrypted file 03 from the capsule file 0402 and stores it as a temporary file 06.

  Step S0703: The export unit 0403 converts the temporary file 06 into the existing DRM system format using the export destination user information acquired in Step S0701.

  Step S0704: The export unit 0403 deletes the temporary file 06.

  As described above, a file can be safely transmitted to another organization that operates the existing DRM system 09 while maintaining the protection state of the file.

  Next, a fifth embodiment of the present invention will be described in detail with reference to FIG.

  When the present invention is used in combination with an existing DRM system 09 like the prior art 3, an import unit 0404 for converting the capsule file 0402 into a file format used in the prior art is provided, so that a safe file for an environment in which the prior art is operated. Enable transfer. When the fifth invention has the above configuration, it becomes possible to receive a file safely from another organization operating the existing DRM system 09 while maintaining the protection state of the file.

Next, the operation of the present embodiment will be described with reference to the flowchart shown in FIG.
Step S0801: The import unit 0404 obtains import source user information from the user.

  Step S0802: The import unit 0404 decrypts the file format of the existing DRM system format and stores it as a temporary file 06.

  Step S0803: The import unit 0404 converts the temporary file 06 into the capsule file 0402 using the export destination user information acquired in Step S0701.

  Step S0804: a step in which the import unit 0404 deletes the temporary file 06.

  As described above, a file can be safely received from another organization operating the existing DRM system 09 while maintaining the file protection state.

  Next, the operation of the best mode for carrying out the present invention will be described using specific examples.

The configuration of a specific embodiment will be described with reference to FIG.
An operating system 12 operates on a computer 11, and a file 13 exists in the computer 11. In this example, the example of the file 13 is “C: \ doc \ doc1.txt”. When the user edits the file 13 on the computer 11, the operating system 12 is set so that the editing program 15 is activated as a standard. In this example, the example of the editing program 15 is “C: \ bin \ notepad.exe”. When the user executes the capsule file generation unit 1401, a capsule file 14 including the encrypted file 13 is generated. In this example, the user example is “sakamoto” and the capsule file 14 example is “C: \ doc \ doc1.txt.cap”. When creating this capsule file 14, the user inputs "xyzxyz" as the encryption password, and registers himself as a user who can view and edit. The user registers the authentication password “iamsakamoto”. When the capsule file 14 is generated, the user can edit the file 13 included in the capsule file 14 by executing the capsule file 1402.

  First, creation of the capsule file 14 ("C: \ doc \ doc1.txt.cap") will be described with reference to FIG.

  Step S01: A step in which the user ("sakamoto") executes the capsule file generation unit 0401 to generate a capsule file 1402 ("C: \ doc \ doc1.txt.cap"). The capsule file generation unit 0401 reads the file 13 (“C: \ doc \ doc1.txt”) designated by the user and creates a capsule file 14. When the creation of the capsule file 14 is completed, the process proceeds to step S02. This step is a process executed in the capsule file generation unit 0401, and the flow of the process will be described later with reference to FIG.

  Step S02: A step in which the user executes the capsule file 1402 created by the capsule file generation means 0401. When the user executes the capsule file 14, the first automatic decryption / encryption means 040201 is automatically activated, and the process proceeds to step S03.

  Step S03: A step in which the first automatic decryption encryption means 040201 authenticates the user ("sakamoto") and confirms the authority. This step is a process executed in the first automatic decryption / encryption means 040201, and the flow of the process will be described later with reference to FIG.

  Step S04: A step of allocating processing according to the result of step S03. Since the user has access authority, the process proceeds to step S05.

  Step S05: The editing program 15 is activated and starts editing the file 13. This step is a process executed in the first automatic decryption encryption unit 040201, and the flow of the process will be described later with reference to FIG.

  Step S06: A step of ending the editing program 15 and ending the editing of the file 13. This step is a process executed in the first automatic decryption encryption unit 040201, and the flow of the process will be described later with reference to FIG.

  Details of step S01 will be described below with reference to FIG.

  Step S0101: A step in which the user designates the file 13 to be protected and executes the capsule file generating unit 0401. When the capsule file generating unit 0401 is activated, the process proceeds to step S0102.

  Step S0102: The execution file generating means 040103 copies the first automatic decryption encryption means 040201 with the name of the capsule file 14 ("C: \ doc \ doc1.txt.cap"). The self-execution program generation means generates the file name of the capsule file 14 by adding the extension “.cap” to the file name (“C: \ doc \ doc1.txt”) specified by the user. The capsule file 14 is created in the same folder as the file 13. When the copying is completed, the process proceeds to step S0103.

  Step S0103: A step of requesting the user a password to be used as a key when the file encryption means 040101 encrypts. The file encryption unit 040101 displays the password input dialog 20 (FIG. 14) and requests the user to input a password. The user inputs the encryption password (“xyzxyz”) in the password input area 2001 of the password input dialog 20 and presses the password input completion button 2002 to complete the password input. When the user inputs the password, the file encryption unit 140101 stores the encryption password ("xyzxyz") in the temporary area, and the process proceeds to step S0104.

  Step S0104: File encryption means 040101 encrypts the file 13 and stores it in a temporary file. The file encryption unit 040101 encrypts the data in the file 13 using the encryption password ("xyzxyz") stored in the temporary area in step S0103, and writes the data in the temporary file ("C: \ tmp \ work \ enc0001.tmp"). . In the encryption of the file 13, data having the same length as the encryption password is acquired from the beginning of the file, and the acquired data and the value of the corresponding character in the encryption password character string are added. The file is encrypted by performing the process on all data in the file. When the encryption of the file 13 is completed, the process proceeds to step S0105.

  Step S0105: The file encryption unit 040101 adds a temporary file to the capsule file 14. The file encryption unit 040101 adds the data of the temporary file ("C: \ tmp \ work \ enc0001.tmp") created in step S0104 to the end of the capsule file 14, and proceeds to step S0106.

  Step S0106: The user authority information setting unit 040102 creates user authority information 040202 and adds it to the capsule file 14. The user authority information setting unit 040202 displays a user designation dialog 21 (FIG. 17) for the user, and allows the user to designate a user who is permitted to view or edit the capsule file 14. A user ID (“sakamoto”) is registered in advance in the user designation dialog 21, and read / write authority for the capsule file 14 is given. The user inputs the identification password (“iamsakamoto”) in the user identification password input area 2101 and presses the user designation completion button 2102.

  When the user finishes specifying, the user authority information setting unit 040102 creates user authority information 040202 in the temporary area, sets the user ID ("sakamoto") specified by the user in the user ID field T04020201 of the user authority information 040202, and the user Is set in the access authority field T04020202, and the user authentication password ("iamsakamoto") specified by the user is set in the user authentication password field T04020203 (FIG. 18). When the user authority information setting unit 040102 completes the creation of the user authority information 040202, the user authority information 040202 created in the temporary area is added to the capsule file 14. When the user authority information setting unit 040102 completes the addition of the user authority information 040202, the process proceeds to step S0107.

  Step S0107: The execution file generating means 040103 creates capsule configuration information 040203 and adds it to the capsule file 14. The execution file generating unit 040103 generates capsule configuration information 040203 in the temporary area. The execution file generation unit 040103 sets the size of the user authority information 040202 added by the user authority information setting unit 040102 to the capsule file 14 in the user authority information size field T04020302 of the capsule configuration information 040203, and the file encryption unit 040101 sets the capsule file 14 Is set in the file size field T04020303 of the capsule configuration information 040203, and the file name ("C: \ doc \ doc1.txt") of the file 13 is set in the file name field T04020304 of the capsule information 040203. Then, the encryption password (“xyzxyz”) used by the file encryption unit 040101 for encrypting the file 13 is set in the password field T04020305 of the capsule configuration information 040203. (Figure 19). Then, the size of the capsule configuration information 040203 is set in the capsule configuration information size field T04020301 of the capsule configuration information 040203, and the capsule configuration information 040203 is added to the end of the capsule file 14. When the execution file generating unit 040103 completes the addition of the capsule configuration information 040203 at the end of the capsule file 14, the process proceeds to step S0108.

  Step S0108: The file encryption unit 040101 deletes the temporary file and the file 13. When the file encryption unit 040101 has confirmed that the capsule file 14 has been normally created, the file encryption unit 040101 deletes the temporary file and the file 13 created in step S0104.

  Hereinafter, details of step S03 will be described with reference to FIG.

  Step S0301: Step in which the file extraction unit 04020101 acquires the capsule configuration information size T04020301 from the capsule file 14. The file extraction unit 04020201 reads the capsule configuration information size T04020301 recorded at a fixed length at the end of the capsule file 14, and proceeds to step S0302.

  Step S0302: A step in which the file extraction unit 04020201 acquires the capsule configuration information 040203 from the capsule file 14. Using the capsule configuration information size T04020301 acquired in step S0301, the file extraction unit 04020201 reads capsule configuration information 040203 for the size indicated by the capsule configuration information size T04020301 from the end of the capsule file 14, and proceeds to step S0303.

  Step S0303: A step in which the file extraction unit 04020201 acquires the user authority information 040202 from the capsule file 14. The file extraction unit 04020201 acquires the user authority information size T04020302 from the capsule configuration information 040203, calculates the offset to the user authority information 040202 by adding the capsule configuration information size T04020301 acquired in step S0301. Then, the file extraction unit 04020201 reads the user authority information 040202 from the capsule file 14 using the calculated offset, and proceeds to step S0304.

  Step S0304: A step in which the file extraction unit 04020101 searches the user authority information 040202 to acquire the authority given to the current user. The file extraction unit 04020101 acquires the user ID (“sakamoto”) of the user who is currently executing the capsule file 14. The file extraction unit 04020101 displays the password input dialog 22 (FIG. 21) and requests the user to input a password for identifying the user. The user inputs the user identification password (“iamsakamoto”) in the password input area 2201 of the password input dialog 22 and presses the password input completion button 2202 to complete the password input.

  Then, the user authority information 040202 is searched for a record that holds the same user ID in the user ID field T04020201 and holds the password ("iamsakamoto") acquired from the user in the password field T04020203. Since there is a record in the user authority information 040202 that holds the user ID (“sakamoto”) in the user ID field T04020201 and the password (“iamsakamoto”) in the password field T04020203, the file extraction unit 04020201 stores the record. Discover and go to step S0305.

  Step S0305: A step of branching the process using the search result in step S0304. In step S0304, the file extraction unit 04020201 finds a record in which the user ID ("sakamoto") of the user who is currently executing the capsule file 14 is registered in the user ID field T04020201 in the user authority information 040202. move on.

  Step S0306: A step in which the file extracting means 04020101 acquires access authority. The file extraction unit 04020201 refers to the access authority field T04020202 of the record found in the user authority information 040202, confirms that the user has access authority to the capsule file 14, and stores the result in the temporary area.

  Details of step S05 will be described below with reference to FIG.

  Step S0501: Step in which the file extraction unit 04020101 creates a temporary folder. The file extraction unit 04020101 creates a temporary folder ("C: \ tmp \ protect \) for expanding the file 13 included in the capsule file 14. When the creation of the temporary folder is completed, the process proceeds to step S0502.

  Step S0502: A step in which the file extracting means 04020101 extracts the encrypted file 13 from the capsule file 14 and stores it in the temporary folder as a temporary file 16 ("C: \ tmp \ protect \ exT0001.txt"). The file extraction unit 04020201 reads the capsule configuration information 040203 from the capsule file 1402 and records it in the temporary area. Then, the file extraction unit 04020201 calculates an offset value from the capsule configuration information size field T04020301, the user authority information size field T04020202 and the file size field T04020203 of the capsule configuration information 040203 to the storage portion of the file 13. The file extraction unit 04020201 obtains the file name of the file 13 (“C: \ doc \ doc1.txt”) from the file name field T04020304 of the capsule configuration information 040203, and the file 13 from the encryption password field T04020305 of the capsule configuration information 040203. Acquire the encrypted password ("xyzxyz") that is encrypted in the temporary area. Then, the file extracting unit 04020201 reads the data of the file 13 encrypted using the calculated offset value, and stores it as a temporary file 16 ("C: \ tmp \ protect \ exT0001.txt") (FIG. 22). When the file extraction unit 04020201 completes saving of the temporary file 16, the process proceeds to step S0503.

  Step S0503: The file decryption means 04020102 decrypts the temporary file 16 ("C: \ tmp \ protect \ exT0001.txt") of the protection folder ("C: \ tmp \ protect \). In step S0502, the temporary file 16 ("C: \ tmp \ protect \ exT0001.txt") is decrypted using the encryption password ("xyzxyz") recorded in the temporary area by the file extraction unit 04020101, and the process proceeds to step S0504.

  Step S0504: The program starting means 04020103 obtains the file name (“C: \ bin \ notepad.exe”) of the editing program 15 corresponding to the file 13. The program activation unit 04020203 uses the file name of the file 13 recorded in the temporary area by the file extraction unit 04020101 in step S0502, and the file name of the editing program 15 associated with the file 13 from the operating system 12 ("C: \ bin \ notepad.exe "). The operating system 12 holds a file association table 18 shown in FIG. The program activation unit 04020203 refers to the record in the file relation table for the extension (".txt") of the file 13, and the file of the editing program 15 associated with the file 13 from the activation program name field T1803 of the file relation table 18 Get the name ("C: \ bin \ notepad.exe"). Then, the program activation unit 04020103 records the acquired file name in the temporary area, and proceeds to step S0505.

  Step S0505: A step in which the program starting means 04020103 starts the editing program 15. The program activation unit 04020203 activates the editing program 15 using the file name ("C: \ bin \ notepad.exe") recorded in the temporary area in step S0504, and proceeds to step S0506.

  Step S0506: A step in which the program monitoring means 04020104 starts monitoring the editing program 15. The program monitoring unit 04020104 monitors whether or not the editing program is being executed and file access (file reading and file writing) of the editing program 15.

  Details of step S06 will be described below with reference to FIG.

  Step S0601: A step in which the user ends the editing program 15 and the program monitoring means 0402020 detects the end of the editing program 15. When the user operates the editing program to end the editing program 15, the program monitoring unit 04020204 detects that the editing program 15 has ended, and the process proceeds to step S0602.

  Step S0602: The file re-encryption means 04020105 encrypts the temporary file 16 ("C: \ tmp \ protect \ exT0001.txt") of the protection folder ("C: \ tmp \ protect \"). The file re-encryption unit 04020105 stores the temporary file ("C: \ tmp \ protect \ exT0001.txt") that has been edited by the editing program 15 in step S0502, and the encryption password ("xyzxyz") recorded in the temporary area by the file extraction unit 04020101. ) And the process proceeds to step S0603.

  Step S0603: The file storage means 04020206 stores the temporary file 16 ("C: \ tmp \ protect \ exT0001.txt") in the capsule file 14. The file storage unit 04020106 replaces the data of the old file 13 in the capsule file 14 with the data of the temporary file, and proceeds to step S0604.

  Step S0604: A step in which the file storage unit 04020206 updates the capsule configuration information 040203 and stores it in the capsule file 130402. The file storage means 04020206 updates the file size field T04020303 of the capsule configuration information 040203 recorded in the temporary area in step S0502 to the size of the temporary file 16 ("C: \ tmp \ protect \ exT0001.txt") replaced in step S0603. The old capsule configuration information 040203 in the capsule file 14 is replaced with the updated capsule configuration information 040203 of the temporary area. When the replacement is completed, the process proceeds to step S0605.

  Step S0605: A step in which the file storage means 04020106 deletes the temporary file 16 ("C: \ tmp \ protect \ exT0001.txt") and the temporary folder ("C: \ tmp \ protect \"). The file storage unit 04020106 releases the protection of the temporary file 16 and deletes the temporary file 16 and the temporary folder.

  As described above, the file 13 generated on the computer 11 is encrypted, and the editing program 15 which is normally used by the user is used as it is. When you finish, you can automatically encrypt the file.

  Finally, the object of the present invention is to encrypt a file generated on a computer, automatically decrypt the file when the user views and edits the file, and automatically encrypts the file when viewing and editing is completed. It is to provide a system that does.

  Another object of the present invention is to provide a system capable of automatically restricting file browsing and editing even if the user browses and edits the file after the expiration date by setting a time limit for viewing the file.

  Another object of the present invention is to provide a system capable of automatically restricting browsing and editing of a file even if a user browses and edits the file after the expiration date by setting the number of times the file can be browsed.

  It is another object of the present invention to provide a system that can securely transmit a file while maintaining the file protection state to another organization that operates a different DRM system.

  It is another object of the present invention to provide a system that can receive a file safely from another organization that operates a different DRM system while maintaining the protection state of the file.

  Another object of the present invention is to achieve the above-mentioned object while using a conventional program as it is without modifying the program for browsing and editing files.

  The effect of the present invention is that the file is encrypted with respect to the file generated on the computer, and when the user views or edits the file, the file is viewed or edited without modifying the program itself. It can be automatically decrypted while being used, and the file can be automatically encrypted when browsing and editing are completed. The reason is that the file automatic decryption encryption system of the present invention has a capsule file generation unit 0401 including a file encryption unit 040101, a user authority information setting unit 040102, and an execution file generation unit 040103, and the capsule file generation unit 0401 is a single unit. It is possible to generate a capsule file 0402 that is an executable file that can be used by the first automatic decryption encryption unit 040201 and the file 03 encrypted by the first automatic decryption encryption unit 040201 and user authority information 040202. The first automatic decryption encryption unit 040201 includes a file extraction unit 04020101, a file decryption unit 04020102, an editing program start unit 04020203, and an editing program monitoring unit. This is because with the 04020104 and file reencryption means 04,020,105 and file storage means 04,020,106.

  In addition, by setting a time limit for browsing the file, it is possible to automatically limit the browsing and editing of the file even if the user views and edits the file after the time limit has passed. The reason for this is that the file automatic decryption / encryption system of the present invention sets a time limit for browsing or editing the encrypted file instead of the file decryption means, and the encrypted file after the set time limit is set. This is because it is provided with an expiration date judgment expression file extraction means for prohibiting browsing and editing.

  In addition, by setting the number of times that a file can be browsed, even if the user browses and edits the file after the expiration date, the file can be automatically browsed and edited. The reason for this is that the file automatic decryption / encryption system of the present invention sets the number of times that the encrypted file can be viewed or edited instead of the file decryption means, and the encrypted file after the set number of times. This is for providing a number-of-times-determining expression file extracting means for prohibiting browsing and editing.

  In addition, the file can be safely transmitted to another organization operating a different DRM system while maintaining the protection state of the file. The reason is that it includes an export unit that takes the capsule file as an input, converts it into a file of a format used on another DRM system, and outputs it.

  In addition, it is possible to receive a file safely from another organization operating a different DRM system while maintaining the protection state of the file. The reason is that it has an import unit that takes a file of a format used in another DRM system as an input, converts it into the capsule file, and outputs it. The object is achieved by using a conventional program as it is without modifying the program for browsing and editing files.

  Each of the above-described embodiments is a preferred embodiment of the present invention, and various modifications can be made without departing from the scope of the present invention. For example, a process for realizing the function of the apparatus may be performed by causing the apparatus to read and execute a program for realizing the function of the computer 01. Further, the program is transmitted to another computer system by a transmission wave via a computer-readable recording medium such as a CD-ROM or a magneto-optical disk, or via a transmission medium such as the Internet or a telephone line. Also good.

  The present invention can be used as a secure file transmission method between different organizations.

It is a block diagram which shows the structure of the 1st Embodiment of this invention. It is a block diagram which shows the structure of the 2nd Embodiment of this invention. It is a block diagram which shows the structure of the 3rd Embodiment of this invention. It is a detailed block diagram of the first automatic decryption encryption means 040201. It is an example of user authority information 040202. It is an example of capsule configuration information 040203. 10 is a configuration diagram when a temporary file 06 is taken out from a capsule file 0402. FIG. This is an example of intercepting event information that occurs when a file is read or written. It is an example of event information that occurs when a file is read or written. It is the whole processing flow for implementing 1st invention of this invention. It is a processing flow in S01. It is a processing flow in S03. It is a processing flow in S05. It is a processing flow in S06. 1 is an overall configuration example for explaining a specific embodiment of the present invention. It is an example of the password input dialog 20 displayed when the file encryption means 040101 requests the user to input a password. It is an example of the user designation dialog 21 displayed when the user authority information setting unit 040102 allows the user to designate a user who is permitted to view or edit the capsule file 14. It is an example of user authority information 040202. It is an example of capsule configuration information 040203. This is an example of the file relation table 1310 held by the operating system 1302. It is an example of a password input dialog 2200 displayed when the file extraction unit 04020201 requests the user to input a password. It is a block diagram when the temporary file 16 is taken out from the capsule file 14. FIG. It is a block diagram which shows the structure of the 4th Embodiment of this invention. It is a detailed block diagram of the second automatic decryption encryption means 040204 in which the file extraction means 04020107 is replaced with a term determination type file extraction means 04020207. It is an example of user authority information 040202 to which time limit information T04020204 is added. FIG. 12 is a detailed configuration diagram of third automatic decryption encryption means 040205 in which file extraction means 04020107 is replaced with frequency determination formula file extraction means 04020208. It is an example of user authority information 040202 to which the number of times information T04020205 is added. It is a block diagram which shows the structure of the 5th Embodiment of this invention. It is a processing flow of the 4th Embodiment of this invention. It is a processing flow of the 5th Embodiment of this invention.

Explanation of symbols

01 Computer 02 Operating System 03 File 04 Automatic File Decryption Encryption System 05 Editing Program 06 Temporary File 07 Event Information 09 Existing DRM System 0401 Capsule File Generating Unit 0402 Capsule File 0403 Export Unit 0404 Import Unit 040101 File Encryption Unit 040102 User Authority Information Setting Means 040103 Execution file generation means 040201 First automatic decryption encryption means 040202 User authority information 040203 Capsule configuration information 040204 Second automatic decryption encryption means 040205 Third automatic decryption encryption means 04020201 File extraction means 04020202 File decryption means 0402020103 Program activation means 04020104 Program supervision Means 04020105 File encryption means 04020106 File storage means 04020107 Expiration date determination formula file extraction means 04020108 Number of times judgment formula file extraction means T04020201 User ID field in user authority information T04020202 Access authority field in user authority information T040020203 User authentication password field in user authority information T04020204 User Time limit information field in authority information T04020205 Time information field in user authority information T04020301 Capsule configuration information size field in capsule configuration information T04020302 User authority information size field in capsule configuration information T04020303 Field in capsule configuration information File size field T04020304 File name field in capsule configuration information T04020305 Encryption password field in capsule configuration information T0701 Event type field in event information T0702 File name field in file location information 11 Computer 12 Operating system 13 File 14 Capsule file 15 Editing program 16 Temporary file 18 File-related table 20 Password input dialog 2001 Password input area 2002 Password input completion button 21 User specification dialog 2101 Password input area 2102 User specification completion button 22 Password input dialog 2201 Password input area 2202 Password input completion button

Claims (19)

  Capsule file generation means for converting a file existing in a computer into a capsule file, and a capsule file that is created in the capsule file generation means and protects the file by encapsulating the encrypted file Automatic file decryption encryption system.   The capsule file generation means sets an executable file generation means for generating a self-executable capsule file, a file encryption means for encrypting the file and recording it in the capsule file, and setting user authority information for decrypting the file and recording the capsule file. 2. The file automatic decryption / encryption system according to claim 1, further comprising: user authority information setting means for performing   When the capsule file has first automatic decryption encryption means for decrypting the encrypted file included therein and the capsule file is used in the same operation as the method for editing a normal file, the file included in the first automatic decryption encryption means is used. 3. The file automatic decryption / encryption system according to claim 1, wherein the file decryption and encryption program is activated.   The capsule file contains only the user authority information generated by the automatic decryption encryption module and the user authority information setting means and the file encrypted by the file encryption means, so that only the user recorded in the user authority information is encrypted. 4. The file automatic decryption / encryption system according to any one of claims 1 to 3, wherein the file cannot be viewed or edited.   The first automatic decryption / encryption means includes a file extraction means for extracting data of a file included in the capsule file, a file decryption means for decrypting encrypted data of the file extracted by the file extraction means, and a decrypted file Editing program starting means for starting an editing program for viewing and editing the data, editing program monitoring means for monitoring the started editing program, and re-encrypting the data of the file edited by the user when the user finishes editing the file 4. The file automatic decryption / encryption system according to claim 3, further comprising: a file re-encryption unit for converting the file data and a file storage unit for storing the file data encrypted by the file re-encryption unit in the capsule file again.   In place of the file decryption means, a time limit judgment type file extraction means for prohibiting browsing and editing of the encrypted file after the set time limit is set by setting a time limit for browsing or editing the encrypted file. The file automatic decryption / encryption system according to claim 5.   In place of the file decryption means, a number-of-times determination type file extraction means is provided that sets the number of times an encrypted file can be viewed or edited, thereby prohibiting browsing and editing of the encrypted file more than the set number of times. The file automatic decryption / encryption system according to claim 5.   8. The file automatic according to claim 1, further comprising an export unit that takes the capsule file as an input, converts the file into a file of a format used on another DRM system, and outputs the file. Decryption encryption system.   9. The file automatic decryption / encryption system according to any one of claims 1 to 8, further comprising an import unit that takes a file of a format used in another DRM system as an input, converts the file into the capsule file, and outputs the capsule file. .   A capsule file generation step of converting a file existing in the computer into a capsule file; and a step of protecting the file by encapsulating the encrypted file created in the capsule file generation step with the capsule file. A file automatic decryption encryption method characterized.   The capsule file generation step sets an executable file generation step for generating a self-executable capsule file, a file encryption step for encrypting the file and recording it in the capsule file, and setting user authority information for decrypting the file and recording it in the capsule file 11. The file automatic decryption / encryption method according to claim 10, further comprising: a user authority information setting step.   When the capsule file is used in the same operation as the method for editing a normal file, the first automatic decryption encryption means for decrypting the encrypted file included in the capsule file decrypts the included file and starts the editing program. The file automatic decryption encryption method according to claim 10 or 11.   The capsule file contains only the user authority information generated by the automatic decryption encryption module and the user authority information setting means and the file encrypted by the file encryption means, so that only the user recorded in the user authority information is encrypted. 13. The file automatic decryption / encryption method according to any one of claims 10 to 12, wherein the file cannot be viewed or edited.   The first automatic decryption / encryption means includes a file extraction step for extracting data of the file included in the capsule file, a file decryption step for decrypting the encrypted data of the file extracted by the file extraction means, and the decrypted file An editing program start step for starting an editing program for viewing and editing data, an editing program monitoring step for monitoring the started editing program, and re-encrypting the data of the file edited by the user when the user finishes editing the file 13. The file automatic decryption / encryption method according to claim 12, further comprising: a file re-encryption step for converting the file data and a file storage step for storing the file data encrypted by the file re-encryption means in the capsule file again.   Instead of the file decryption step, there is a time limit judgment type file extraction step for prohibiting browsing and editing of the encrypted file after the set time limit by setting a time limit for browsing or editing the encrypted file. The file automatic decryption / encryption method according to claim 14.   In place of the file decryption step, there is a number of times determination type file extraction step for prohibiting browsing and editing of the encrypted file by setting the number of times that the encrypted file can be viewed or edited. The file automatic decryption / encryption method according to claim 14.   The file automatic according to any one of claims 10 to 16, further comprising an export step in which the capsule file is input, converted into a file of a format used on another DRM system, and output. Decryption encryption method.   The file automatic decryption encryption method according to any one of claims 10 to 17, further comprising an import step of taking a file of a format used in another DRM system as an input, converting the file into the capsule file, and outputting the capsule file. .   A program for causing a computer system to realize the function according to any one of claims 1 to 9.

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