JP2004070674A - Data protecting device, data protecting method and program in electronic data interchange system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data protecting device, a data protecting method and a program for the same capable of executing security control with a high degree of safety. <P>SOLUTION: The system holds a security level given to each user and file in a control information storage part 302, holds information on an access record from each user in an access record information storage part 303, compares the security level of the user and the file, and computes the security level based on the user's access record from the user's security level and the information on the access record. The system compares the computed security level and the security level of the file, determines whether the user is permitted to access the file by a determination means in a contents server 3. When judgement that the access is permitted is made, the system transmits the requested file to a client 4 on a user's side through the Internet 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a data protection device, a data protection method, and a program used in an electronic data exchange (hereinafter referred to as “EDI”) system by a server system placed on the Internet.
[0002]
[Prior art]
2. Description of the Related Art In recent years, with the spread of the Internet, a movement to digitize the exchange of data such as slips and drawings between companies has been rapidly expanding. In particular, exchanges with affiliated companies through the EDI system are effective in reducing labor and time compared to conventional paper transactions by mail or the like, and are about to be widely spread.
[0003]
Here, in the EDI system using the Internet, since the Internet is an extremely open environment, weakness of data protection becomes a problem. In order to realize an EDI system using the Internet, it is necessary to place EDI data outside a firewall, and thus it is necessary to protect data outside the firewall.
[0004]
With respect to such a problem of data protection, a method using information encryption and a security protocol has been proposed and put into practical use. A method of managing security according to the authority and affiliation of a user or the confidentiality of a content file has been proposed, so that data protection can be performed finely.
[0005]
[Problems to be solved by the invention]
However, in the above-mentioned conventional technology, management is performed by an access right set in advance, and there is a problem that if an unauthorized access due to spoofing over security occurs, it cannot be found, or if it is found, the response is delayed. .
[0006]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. In an EDI system using the Internet, a highly secure security management that eliminates unauthorized access and can quickly respond to unauthorized access. It is an object of the present invention to provide a data protection device and a data protection method capable of performing the above, and a program used therefor.
[0007]
[Means for Solving the Problems]
A data protection device according to the present invention is a data protection device in an electronic data exchange system based on a server system placed on the Internet,
Management information holding means for holding a security level given to each user in advance according to the management capability of the electronic data and a security level given to each file according to the content thereof;
Access result information holding means for holding access result information from each user,
The security level of the user is compared with the security level of the file, the access pattern estimated from the security level of the user and the access result information from the user, and the user who has requested access to the file. The security level based on the access record is calculated from the access pattern of the user, and the security level based on the calculated access record is compared with the security level of the file for which the access request is made. Determining means for determining whether or not access to the file for which the access request has been made is permitted;
Transmitting means for transmitting the requested file to the user-side client having made the access request via the Internet, when it is determined by the determining means that access is permitted;
It is provided with.
[0008]
In addition, the apparatus includes an encryption processing unit that encrypts and decrypts each of the files, and an encrypted content storage unit that stores the encrypted files.
[0009]
Further, a UDF (Universal Disk Format) file system is used as an installation location of the encrypted content storage means and the management information holding means.
[0010]
Further, when the determining means determines that the access of the user who made the access request is not permitted, a request for confirming whether or not the user who made the access request has the registered access right is determined. Authentication means for performing authentication, wherein the authentication means has the access right, and when it is determined that the access can be permitted, the transmission means transmits the requested file to the access request via the Internet. This is transmitted to the client on the user side that performed the above.
[0011]
Further, a notifying means is provided for notifying an administrator managing the server system of the result of the determination when the determining means determines that access of the user who has made the access request is not permitted. Things.
[0012]
The management information holding means is provided in a storage device, and is provided in an area of the storage device which is not normally accessed from a file system.
[0013]
Further, a sector address obtaining means for obtaining a sector address of an area not normally accessed from the file system, and information to be held in the management information holding means for the sector having the sector address obtained by the sector address obtaining means. And writing means for reading information written by the writing means.
[0014]
Further, the determination means is loaded at the time of execution via a communication line different from the Internet.
[0015]
A data protection method according to the present invention is a data protection method in an electronic data exchange system using a server system placed on the Internet,
Holding a security level given to each user in advance according to the management capability of the electronic data, a security level given to each file according to the content thereof, and access record information from each user;
A first step of receiving a request from a user to access a file via the Internet;
A second step of comparing the security level of the requested user with the security level of the requested file;
If the security level of the requested user is lower than the security level of the requested file, access is not permitted and the security level of the requested user is the security level of the requested file. If the file size is larger than the security level, the security level based on the access record is determined from the access level estimated from the security level of the user who made the access request and the access record information from the user and the access pattern of the user who made the access request to the file. The third step of calculating the level,
A fourth step of comparing the security level based on the access results calculated in the third step with the security level of the requested file;
A fifth step of determining whether or not the user who has made the access request is permitted to access the requested file based on the result of the comparison in the fourth step;
In the fifth step, when it is determined that the access is permitted, a sixth step of transmitting the requested file to the client of the user who has requested the access via the Internet,
It has.
[0016]
Further, each of the files is encrypted and transmitted to the client on the side of the user who has made the access request.
[0017]
Also, the encrypted file, the security level of the user, and the security level of the file are stored using a UDF (Universal Disk Format) file system.
[0018]
Further, when it is determined in the fifth step that access of the user who made the access request is not permitted, it is determined whether the user who made the access request has the registered access right. An authentication unit for performing re-authentication, wherein the authentication unit has the access right and, when it is determined that the access is permitted, makes the access request to the requested file via the Internet. This is sent to the client on the user side.
[0019]
If it is determined in the fifth step that access of the user who has made the access request is not permitted, the result of the determination is notified to an administrator who manages the server system.
[0020]
The security level of the user and the security level of the file are provided in an area of the storage device that is not normally accessed from a file system.
[0021]
Further, a sector address of an area that is not normally accessed from the file system is obtained, information of the security level of the user and the security level of the file are written in a sector having the obtained sector address, and the written information is written. What you read.
[0022]
Further, the means for executing the first to sixth steps is a means for loading via a communication line different from the Internet when executing the steps.
[0023]
A program according to the present invention is a program used for data protection in an electronic data exchange system by a server system placed on the Internet,
Management information holding means for holding a security level given to each user in advance according to the management capability of the electronic data and a security level given to each file according to the content thereof;
Access result information holding means for holding access result information from each user,
The security level of the user is compared with the security level of the file, the access pattern estimated from the security level of the user and the access result information from the user, and the user who has requested access to the file. The security level based on the access record is calculated from the access pattern of the user, and the security level based on the calculated access record is compared with the security level of the file for which the access request is made. Determining means for determining whether or not access to the file for which the access request has been made is permitted;
Transmitting means for transmitting the requested file to the user-side client having made the access request via the Internet, when it is determined by the determining means that access is permitted;
Function.
[0024]
Further, the present invention causes the computer to function as encryption processing means for encrypting and decrypting each of the files, and as encrypted content storage means for storing the encrypted files.
[0025]
Further, a UDF (Universal Disk Format) file system is used as an installation location of the encrypted content storage means and the management information holding means.
[0026]
Further, when the determination unit determines that the access of the user who made the access request is not permitted, the computer checks whether the user who made the access request has the registered access right. Functioning as an authentication means for performing re-authentication for the purpose of the present invention, and in the authentication means, when it is determined that the user has the access right and the access can be permitted, the transmission means transmits the requested content via the Internet. Is transmitted to the client on the side of the user who made the access request.
[0027]
A notifying means for notifying an administrator managing the server system of a result of the determination when the determining means determines that access of the user who made the access request is not permitted; Function.
[0028]
Further, the management information holding means is provided in an area which is not normally accessed from the file system.
[0029]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a data protection device and a data protection method in an EDI system according to the present invention and a recording medium used for the same will be described with reference to the drawings.
[0030]
Embodiment 1 FIG.
FIG. 1 is a block diagram illustrating an environment in which a data protection device (hereinafter, simply referred to as a data protection device) in the EDI system according to the first embodiment is realized and a configuration of the data protection device.
[0031]
In FIG. 1, 1 is the Internet, 2 is an in-house LAN, 3 is a content server holding data exchanged with a business partner, 4 is a PC (personal computer) (hereinafter, referred to as a client) installed at the business partner, and 5 is a client. This is a firewall, and information security of the in-house LAN 2 is ensured by the firewall 5. Although only one client 4 is shown in the figure, a plurality of clients 4 can be installed.
[0032]
Reference numeral 301 denotes a plaintext content storage unit, 302 denotes a management information storage unit (management information storage unit), and 303 denotes an access result information storage unit (access result information storage unit), which are provided in the content server 3. Reference numeral 401 denotes a content storage unit provided in the client 4.
[0033]
The plaintext content storage unit 301 stores a plaintext content file, and access to the plaintext content file is permitted only by local access. The management information storage unit 302 stores a user management database for managing the security level of each user and a content management database for managing the security level of each content file. Hereinafter, the content management database and the user management database stored in the management information storage unit 302 are collectively referred to as management information.
[0034]
FIG. 2 is a diagram illustrating an example of the contents of the user management database. As shown in the figure, the user management database includes information on user names, group names, security levels, names, and affiliations.
[0035]
The security level included in the user management database indicates a security level set for each user, and is represented by, for example, an integer from 1 to 10, and the higher the numerical value, the higher the security level.
[0036]
FIG. 3 is a diagram illustrating an example of the content of the content management database. As shown in the figure, the content management database includes information on file names, access groups, security levels, and directories.
[0037]
The access group of the content management database is information indicating that only a user belonging to a group included in the user management database can access the file.
[0038]
The security level included in the content management database is represented by an integer from 1 to 10, for example. The higher the number, the higher the number, the lower the level, such as the creator of the document, the lower the number.The security level of the content file depends on the type of the content file, for example, for reference. Is set low, and changeable or editable is set high. When the security level set for the user is higher than the security level set for each content file, this indicates that the user can access the content file.
[0039]
The registration and editing of the management information in the user management database and the content management database described above are performed by the administrator of the content server 3 using management software using a dedicated secure API (application programming interface). Specifically, management information input from input means such as a keyboard is stored in the user management database and the content management database via a dedicated secure API provided in the content server 3. However, registration in the content management database is performed by a manager using management software using a secure API when registering a content file.
[0040]
The processing content when the content file is actually extracted using the management information and transmitted to the client 4 will be described below.
[0041]
First, a user logs in to the client 4. Thereafter, an access request is made to the content file via the Internet 1, and the content server 3 receiving the request activates a dedicated secure API. More specifically, when the client 4 specifies the port number of the FTP daemon of the content server 3, the content server 3 that recognizes the specification calls the secure API.
[0042]
FIG. 4 is a flowchart showing the processing contents of the secure API. The access record information storage unit 303 stores access record information for calculating a security level based on the access record of each user. Hereinafter, information stored in the access result information storage unit 303 is referred to as access result information. The access result information is information including information that can estimate a user name, an access cycle, an access frequency, and an access pattern of a user represented by a conventional use day of the week and a use time period. The calculation of the security level based on the access result of the user is calculated from the access pattern estimated from the security level of the user and the access result information from the user, and the access pattern of the user who has requested the access to the file. The security level is calculated to be low for suspicious accesses, such as when the access pattern of a user who has made an access request to a file is different from normal, or when the file is frequently accessed in a short cycle.
[0043]
The secure API of the content server 3 acquires information such as the user name transmitted from the client 4 and the file name of the requested content file (S401), obtains management information from the user management database and the content management database, and obtains the user's information. It functions as a determination unit that compares the group name with the access group of the content file and makes a determination (S402).
[0044]
If the group names do not match, the content file cannot be accessed.
[0045]
As a result of the determination, if the group names match, the secure API on the content server 3 side compares and determines the security level (S404).
[0046]
As a result of the determination, if the security level of the user is lower than the security level of the content file, access to the content file is not permitted (S405: No).
[0047]
As a result of the determination, if the security level of the user is equal to or higher than the security level of the content file (S405: Yes), the secure API of the content server 3 determines the security level calculated based on the security level of the user and the access result information. The level and the security level of the content file are compared and determined (S406).
[0048]
As a result of the determination, if the security level calculated based on the security level of the user and the access record information is lower than the security level of the content file (S407: No), the access to the content file is not permitted.
[0049]
As a result of the determination, if the security level calculated based on the security level of the user and the access record information is equal to or higher than the security level of the content file (S407: Yes), the content file can be accessed. Performs transmission processing of the content file stored in the plaintext content storage unit 301 of the content server 3 via the Internet 1 (S408).
[0050]
Upon receiving the content file, the client 4 stores the received content file in the content storage unit 401. The stored content file can be used by various applications.
[0051]
As described above, according to the present embodiment, in an EDI system using the Internet, by implementing data protection with a fine security level set based on a user's access record, unauthorized access can be prevented. Eliminate it and perform highly secure security management.
[0052]
In the present embodiment, a program that causes a computer to function as a management information storage unit (management information storage unit) 302, an access result information storage unit (access result information storage unit) 303, and a determination unit / transmission unit (secure API) Is recorded on a recording medium, and the computer reads the recording medium to execute the processing of S401 to S408.
[0053]
Embodiment 2 FIG.
FIG. 5 is a block diagram showing an environment in which the data protection device according to the second embodiment is realized and a configuration of the data protection device. The same reference numerals as those in FIG. 1 denote the same or corresponding parts.
[0054]
In the present embodiment, an encrypted content storage unit (encrypted content storage unit) 304 and an encryption processing unit (encryption processing unit) 305 are added to the content server 3, and an encryption processing unit 402 is added to the client 4. The encryption processing units 305 and 402 perform encryption and decryption processing of the content file.
[0055]
In the data protection device, various processes are realized by using a dedicated secure API as described later, but the content file is also encrypted by using the dedicated secure API. As for the encryption method, various encryption methods can be used according to the confidentiality of the information. A known technique can be used for the encryption method itself.
[0056]
The plaintext content storage unit 301 stores plaintext content files. In order to avoid holding the plaintext content file outside the firewall 5, for example, in a state where the content server 3 is not connected to the Internet 1, a computer-readable portable type such as a flexible disk or a CD-ROM is used. The plaintext content file recorded on the recording medium is encrypted by the encryption processing unit 305, and the plaintext content file is connected to the Internet 1 without being present in the content server 3.
[0057]
The encrypted content storage unit 304 stores the plaintext content file encrypted by the encryption processing unit 305. As the encrypted content storage unit 304, various storage units such as a hard disk device and a flexible disk device can be used.
[0058]
The management information storage unit 302 stores a user management database for managing the security level of each user and a content management database for managing the security level of each content file.
[0059]
FIG. 6 is a diagram illustrating an example of the contents of the user management database. As shown in the figure, the user management database includes common key information in addition to the user name, group name, security level, name, and affiliation information described in the first embodiment.
[0060]
The common key means that when a user sends a decrypted plaintext content file from the encrypted content storage unit 304 onto the Internet 1, the plaintext content file is re-encrypted and the re-encrypted plaintext content file is re-encrypted. This is a key used for compounding on the client 4 side that has received it. As will be described later, this common key is different from the key used when encrypting a plaintext content file stored in the plaintext content storage unit 301 and storing it in the encrypted content storage unit 304.
[0061]
FIG. 7 is a diagram illustrating an example of the content of the content management database. As shown in the figure, the content management database includes content key information in addition to the file name, access group, security level, and directory information described in the first embodiment.
[0062]
The content key is a key used in the content server 3 for encryption when storing a plaintext content file in the encrypted content storage unit 304 and decryption when reading the content file from the encrypted content storage unit 304. As described above, the plaintext content file composited with the content key is re-encrypted with the common key and transmitted over the Internet.
[0063]
The registration and editing of the management information in the user management database and the content management database described above are performed by the administrator of the content server 3 using management software using a dedicated secure API. Specifically, management information input from input means such as a keyboard is stored in the user management database and the content management database via a dedicated secure API provided in the content server 3. However, the registration in the content management database is automatically performed by the secure API when the plaintext content file is encrypted.
[0064]
The processing content when an encrypted content file is actually extracted using the management information and transmitted to the client 4 will be described below.
[0065]
First, a user logs in to the client 4. Thereafter, an access request is made to the content file via the Internet 1, and the content server 3 receiving the request activates a dedicated secure API. More specifically, when the client 4 specifies the port number of the FTP daemon of the content server 3, the content server 3 that recognizes the specification calls the secure API.
[0066]
FIG. 8 is a flowchart showing the processing contents of the secure API. The processing from S801 to S806 is the same as that from S401 to S406 in the first embodiment, and a description thereof will be omitted.
[0067]
The security level based on the user's security level and the access information is compared with the security level of the content file, and the security level calculated based on the user's security level and the access result information is lower than the security level of the content file. (S807: No), access to the content file is not permitted.
[0068]
If the security level calculated based on the security level of the user and the access record information is equal to or higher than the security level of the content file (S807: Yes, since the content file can be accessed, the content file key is used. A decryption process of the encrypted content file is performed (S808).
[0069]
The plaintext content file obtained by the decryption process is compressed (S809), and then encrypted again using the common key (S810). Here, the reason why encryption is performed after compression is that compression cannot be performed if encryption is performed first.
[0070]
The encrypted content file is transmitted to the client 4 via the Internet 1 (S811).
[0071]
Next, processing contents on the client 4 side that has received the encrypted content file will be described. FIG. 9 is a flowchart showing the processing contents on the client 4 side which has received the encrypted content file.
[0072]
When the client 4 receives the compressed and encrypted content file (S901), it decrypts it using a common key (S902). Here, the reason why the decoding is performed first is that the data cannot be expanded unless it is in a composite state.
[0073]
After the compressed plaintext content file is decompressed (S903), and converted into a normal plaintext content file, the plaintext content file is encrypted again using the common key in order to store it in the content storage unit 402 of the client 4 (S904). .
[0074]
The encrypted plaintext content file is stored in the content storage unit 402 (S905), and the process on the client 4 side ends.
[0075]
Next, a process for reading and using the encrypted content file stored in the content storage unit 402 will be described.
[0076]
In order to use the encrypted content file on the client 4 side, a PC card having a security function is used. By installing a PC card on the client 4 side and inputting a password, the encrypted content file is composited and can be used in various applications. It should be noted that a known technique can be used for the decryption processing using the PC card.
[0077]
As described above, according to the present embodiment, in an EDI system using the Internet, stronger data protection can be realized by encrypting content files.
[0078]
In this embodiment, a program that causes a computer to function as an encrypted content storage unit (encrypted content storage unit) 304 and an encryption processing unit (encryption processing unit) 305 is recorded on a recording medium. Then, the processes of S801 to S811 are executed by reading the data.
[0079]
Embodiment 3 FIG.
FIG. 10 is a flowchart showing the processing content of the secure API according to the third embodiment. In the present embodiment, an authentication unit for re-authenticating a user is added to the processing of the first embodiment. Hereinafter, the processing content will be described.
[0080]
The processing from S1001 to S1006 is the same as the processing from S401 to S406 in the first embodiment.
[0081]
The security level based on the user's security level and the access information is compared with the security level of the content file, and the security level calculated based on the user's security level and the access result information exceeds the security level of the content file. If yes (S1007: Yes), since access to the content file is possible, the secure API performs content file transmission processing via the Internet 1 (S1010).
[0082]
If the security level calculated based on the security level of the user and the access record information is lower than the security level of the content file (S1007: No), the user is re-authenticated (S1008) and the authentication result is determined. (S1009). Re-authentication confirms whether the user has the registered access right.
[0083]
If the authentication result is good, it is determined that the user has the access right and the content file can be accessed, and the secure API performs the content file transmission processing via the Internet 1 (S1010).
[0084]
As described above, when access is not permitted by the determination unit based on the access record information, by adding an authentication unit for performing re-authentication, it is possible to automatically respond to the user when access is rejected. In addition, the burden on the user of the server-side administrator can be reduced.
[0085]
In the present embodiment, a program that causes a computer to function as an authentication unit is recorded on a recording medium, and the computer reads the recording medium to execute the processing of S1001 to S1010.
[0086]
Embodiment 4 FIG.
FIG. 11 is a flowchart showing the processing content of the secure API according to the fourth embodiment. In the present embodiment, a process for notifying a server-side administrator is added to the process of the first embodiment. Hereinafter, the processing content will be described.
[0087]
The processing from S1101 to S1106 is the same as the processing from S401 to S406 in the first embodiment.
[0088]
The security level based on the user's security level and the access information is compared with the security level of the content file, and the security level calculated based on the user's security level and the access result information exceeds the security level of the content file. If yes (S1109: Yes), since access to the content file is possible, the secure API performs content file transmission processing via the Internet 1 (S1110).
[0089]
If the security level calculated based on the security level of the user and the access result information is lower than the security level of the content file (S1107: No), the administrator is notified (S1108), and the content file is deleted. No access is allowed.
[0090]
As described above, by adding the notification means for notifying the administrator when the access is not permitted by the determination means based on the access result information, the response to the user when the access is rejected can be flexibly determined by the administrator. Can be performed in a more detailed manner.
[0091]
In the present embodiment, a program that causes a computer to function as a notification unit to the server-side administrator is recorded on a recording medium, and the computer reads the recording medium to execute the above-described processing in S1001 to S1010.
[0092]
Embodiment 5 FIG.
In FIG. 5, a UDF file system standardized by ISO 13346 can be used as the encrypted content storage unit 304, the management information storage unit 302, and the access result information storage unit 303.
[0093]
By using a UDF file system having a high-level security function and a backup function, stronger security can be secured for the entire EDI system.
[0094]
Embodiment 6 FIG.
In the first to fifth embodiments, the secure API refers to the access record information and the management information. Normally, these are held by data holding means such as a DB. However, by writing these in an area of the storage device that is not normally used by the OS or the like, further security of the access record information and the management information is to be achieved. Can be.
[0095]
FIG. 12 is a diagram for describing an area where the secure API writes the access record information and the management information. In the figure, the access record information and the management information are written in areas indicated as “Hidden Sector” and “unused area” (both are referred to as unused areas).
[0096]
FIG. 13 is a flowchart showing the processing contents when the secure API writes the access result information and the management information to the unused area in the present embodiment.
[0097]
First, the secure API acquires a sector address of an unused area (S1301). Specifically, in a storage device such as a hard disk used as the access record information storage unit 303 and the management information storage unit 302 shown in FIG. 1, the data area managed by the partition table, From the information of the leading sector (a) and the ending sector (b), the sector addresses of the unused areas (c) and (d) can be obtained.
[0098]
Next, the secure API calls the device driver included in the BIOS (Basic Input / Output System) using a system call, and accesses the access result information or the number of bytes of the management information and the parameters such as the sector address of the write position and the access result. Information or management information is passed (S1302). As a result, data is written to the unused area by the device driver (S1303). The access record information or management information written in the unused area can be read out by using the secure API as in the writing.
[0099]
As described above, by retaining the access record information and the management information in an area that is not normally accessed from the OS, it is possible to prevent unauthorized access to the access record information and the management information by means other than the secure API, and from the viewpoint of security. It will be preferable.
[0100]
Embodiment 7 FIG.
FIG. 14 is a block diagram showing an environment in which the protection device is realized in the EDI system according to the seventh embodiment and a configuration of the data protection device. The same reference numerals as those in FIG. 1 denote the same or corresponding parts.
[0101]
In the first embodiment, the secure API used for the data protection device is stored in the HDD on the content server 3 as a program realized in an environment having access record information and management information.
[0102]
In the present embodiment, a program realized in an environment having the access record information and the management information is stored in another recording device provided at the end of a communication line 6 different from the Internet 1, for example, a hard disk of a computer. And a program storage unit 306 realized by a recording medium such as a RAM.
[0103]
In this case, when the content server 3 executes a program using the secure API, the secure API is loaded via the communication line 6 and executed on the main memory. If the program becomes executable by an intruder after receiving unauthorized access to the content server 3, the secure API cannot be used by shutting down the communication line 6 or stopping the program storage unit 306 or ejecting the recording medium. It is possible to prevent unauthorized access to the access record information and management information.
[0104]
As described above, by placing the program for realizing the secure API in a place other than the HDD of the content server 3 and loading the program via the communication line 36 different from the Internet 1 when executing the program, the access record information and the management information Unauthorized access to the server can be prevented. When used in combination with the means for notifying the server-side administrator of the fourth embodiment, the server-side administrator can respond quickly and the effect is particularly large.
[0105]
【The invention's effect】
According to the data protection device according to the present invention, a data protection device in an electronic data exchange system by a server system placed on the Internet,
Management information holding means for holding a security level given to each user in advance according to the management capability of the electronic data and a security level given to each file according to the content thereof;
Access result information holding means for holding access result information from each user,
The security level of the user is compared with the security level of the file, the access pattern estimated from the security level of the user and the access result information from the user, and the user who has requested access to the file. The security level based on the access record is calculated from the access pattern of the user, and the security level based on the calculated access record is compared with the security level of the file for which the access request is made. Determining means for determining whether or not access to the file for which the access request has been made is permitted;
Transmitting means for transmitting the requested file to the user-side client having made the access request via the Internet, when it is determined by the determining means that access is permitted;
Therefore, unauthorized access can be eliminated and highly secure security management can be performed.
[0106]
Further, since the apparatus includes the encryption processing means for encrypting and decrypting each of the files and the encrypted content storage means for storing the encrypted files, stronger security can be ensured.
[0107]
Further, since the UDF (Universal Disk Format) file system is used as the installation location of the encrypted content storage means and the management information holding means, stronger security can be ensured.
[0108]
Further, when the determining means determines that the access of the user who made the access request is not permitted, a request for confirming whether or not the user who made the access request has the registered access right is determined. Authentication means for performing authentication, wherein the authentication means has the access right, and when it is determined that the access can be permitted, the transmission means transmits the requested file to the access request via the Internet. Therefore, when it is determined that the access of the user is not permitted, the burden of the server-side administrator on the user can be reduced.
[0109]
Further, a notifying means is provided for notifying an administrator managing the server system of the result of the determination when the determining means determines that access of the user who has made the access request is not permitted. Therefore, a more detailed response to a user or the like at the time of access denial is possible.
[0110]
The management information holding means is provided in the storage device and is provided in an area which is not normally accessed from the file system in the storage device. Further security of the stored information can be achieved.
[0111]
Further, a sector address obtaining means for obtaining a sector address of an area not normally accessed from the file system, and information to be held in the management information holding means for the sector having the sector address obtained by the sector address obtaining means. And writing means for reading information written by the writing means, so that writing and reading to and from an area which is not normally accessed from the file system can be easily performed.
[0112]
In addition, since the determination unit is loaded when executed via a communication line different from the Internet, it is possible to prevent unauthorized access to the access result information holding unit and the management information holding unit.
[0113]
A data protection method according to the present invention is a data protection method in an electronic data exchange system using a server system placed on the Internet,
Holding the security level given to each user in advance, the security level given to each file, and the access record information from each user,
A first step of receiving a request from a user to access a file via the Internet;
A second step of comparing the security level of the requested user with the security level of the requested file;
If the security level of the requested user is lower than the security level of the requested file, access is not permitted and the security level of the requested user is the security level of the requested file. If it is larger than the third level, a third step of calculating a security level based on the access result of the user based on the security level and the access result information of the user who made the access request,
A fourth step of comparing the security level based on the access results calculated in the third step with the security level of the requested file;
A fifth step of determining whether or not the user who has made the access request is permitted to access the requested file based on the result of the comparison in the fourth step;
In the fifth step, when it is determined that the access is permitted, a sixth step of transmitting the requested file to the client of the user who has requested the access via the Internet,
Therefore, unauthorized access can be eliminated and highly secure security management can be performed.
[0114]
In addition, since each of the files is encrypted and transmitted to the client on the side of the user who has made the access request, stronger security can be ensured.
[0115]
Further, since the encrypted file, the security level of the user, and the security level of the file are stored using the UDF file system, stronger security can be ensured.
[0116]
Further, when it is determined in the fifth step that access of the user who made the access request is not permitted, an authentication unit for re-authenticating the user who made the access request is provided. If it is determined that the access is permitted, the requested file is transmitted to the user's client that made the access request via the Internet, and thus it is determined that the user's access is not permitted. In this case, the burden on the user of the server-side administrator can be reduced.
[0117]
Further, when it is determined in the fifth step that access of the user who has made the access request is not permitted, the result of the determination is notified to an administrator who manages the server system. In addition, when access is denied, a more detailed response to a user or the like can be performed.
[0118]
The security level of the user and the security level of the file are provided in an area of the storage device that is not normally accessed from the file system. Further security of information can be achieved.
[0119]
Further, a sector address of an area that is not normally accessed from the file system is obtained, information of the security level of the user and the security level of the file are written in a sector having the obtained sector address, and the written information is written. Since it is read, writing and reading to and from an area not normally accessed from the file system can be easily performed.
[0120]
Further, since the means for executing the first to sixth steps is to be loaded at the time of execution via a communication line different from the Internet, the access result information and the security level of the user and the file are used. Unauthorized access to the information on the information can be prevented.
[0121]
A program according to the present invention is a program used for data protection in an electronic data exchange system by a server system placed on the Internet,
Management information holding means for holding a security level given to each user in advance according to the management capability of the electronic data and a security level given to each file according to the content thereof;
Access result information holding means for holding access result information from each user,
The security level of the user is compared with the security level of the file, the access pattern estimated from the security level of the user and the access result information from the user, and the user who has requested access to the file. The security level based on the access record is calculated from the access pattern of the user, and the security level based on the calculated access record is compared with the security level of the file for which the access request is made. Determining means for determining whether or not access to the file for which the access request has been made is permitted;
Transmitting means for transmitting the requested file to the user-side client having made the access request via the Internet, when it is determined by the determining means that access is permitted;
As a result, unauthorized access can be eliminated and highly secure security management can be performed.
[0122]
Further, since the computer functions as encryption processing means for encrypting and decrypting each of the above files and encrypted content storage means for storing the encrypted files, stronger security can be ensured.
[0123]
Further, since the UDF file system is used as the installation location of the encrypted content storage unit and the management information holding unit, stronger security can be secured.
[0124]
Further, when the determination unit determines that the access of the user who made the access request is not permitted, the computer checks whether the user who made the access request has the registered access right. Functioning as an authentication means for performing re-authentication for the purpose of the present invention, and in the authentication means, when it is determined that the user has the access right and the access can be permitted, the transmission means transmits the requested content via the Internet. Therefore, when it is determined that the access of the user is not permitted, it is possible to reduce the burden on the server-side administrator to deal with the user.
[0125]
A notifying means for notifying an administrator managing the server system of a result of the determination when the determining means determines that access of the user who made the access request is not permitted; Therefore, it is possible to respond more finely to a user or the like when access is denied.
[0126]
Further, since the management information holding means is provided in an area which is not normally accessed from the file system, it is possible to further secure the access result information and the information regarding the security level of the user and the file. .
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an environment in which a data protection device is implemented in an EDI system according to a first embodiment and a configuration of the data protection device.
FIG. 2 is a diagram showing an example of the contents of a user management database.
FIG. 3 is a diagram showing an example of the contents of a content management database.
FIG. 4 is a flowchart showing processing contents of a secure API according to the first embodiment.
FIG. 5 is a block diagram illustrating an environment in which the data protection device according to the second embodiment is realized and a configuration of the data protection device;
FIG. 6 is a diagram showing an example of the contents of a user management database.
FIG. 7 is a diagram showing an example of the contents of a content management database.
FIG. 8 is a flowchart showing processing contents of a secure API according to the second embodiment.
FIG. 9 is a flowchart illustrating processing on the client side that has received an encrypted content file.
FIG. 10 is a flowchart showing processing contents of a secure API according to the third embodiment.
FIG. 11 is a flowchart showing processing contents of a secure API according to the fourth embodiment.
FIG. 12 is a diagram for describing an area where a secure API writes access result information and management information.
FIG. 13 is a flowchart showing processing contents when the secure API writes access result information and management information to an unused area in the fourth embodiment.
FIG. 14 is a block diagram illustrating an environment in which a protection device is realized in an EDI system according to a seventh embodiment and a configuration of a data protection device;
[Explanation of symbols]
1 Internet, 2 internal LAN, 3 content server,
4 clients, 5 firewalls, 301 plaintext content storage,
302 management information storage unit, 303 access result information storage unit,
304 encrypted content storage, 305, 306 program storage,
402 encryption processing unit, 401, 402 content storage unit.

Claims (22)

A data protection device in an electronic data exchange system by a server system placed on the Internet,
Management information holding means for holding a security level given to each user in advance according to the management capability of the electronic data and a security level given to each file according to the content thereof;
Access result information holding means for holding access result information from each user,
The security level of the user is compared with the security level of the file, the access pattern estimated from the security level of the user and the access result information from the user, and the user who has requested access to the file. The security level based on the access record is calculated from the access pattern of the user, and the security level based on the calculated access record is compared with the security level of the file for which the access request is made. Determining means for determining whether or not access to the file for which the access request has been made is permitted;
Transmitting means for transmitting the requested file to the user-side client having made the access request via the Internet, when it is determined by the determining means that access is permitted;
A data protection device comprising: 2. The data protection device according to claim 1, further comprising an encryption processing unit that encrypts and decrypts each of the files, and an encrypted content storage unit that stores the encrypted files. 3. The data protection device according to claim 2, wherein a UDF (universal disk format) file system is used as a place where the encrypted content storage unit and the management information holding unit are installed. When the determining means determines that the access of the user who made the access request is not permitted, re-authentication for confirming whether the user who made the access request has the registered access right is performed. The transmitting means makes the requested file through the Internet when the authenticating means has the access right and it is determined that the access can be permitted. 2. The data protection device according to claim 1, wherein the data is transmitted to a user-side client. When the determining unit determines that access of the user who has made the access request is not permitted, a notifying unit is provided for notifying an administrator managing the server system of a result of the determination. The data protection device according to claim 1, wherein 2. The data protection device according to claim 1, wherein the management information holding means is provided in a storage device, and is provided in an area of the storage device that is not normally accessed from a file system. A sector address obtaining means for obtaining a sector address of an area not normally accessed from the file system, and writing information to be held in the management information holding means in a sector having the sector address obtained by the sector address obtaining means. 7. The data protection device according to claim 6, further comprising: a writing unit; and a reading unit that reads information written by the writing unit. 2. The data protection device according to claim 1, wherein the determination unit is loaded when executing the determination via a communication line different from the Internet. A data protection method in an electronic data exchange system by a server system placed on the Internet,
Holding a security level given to each user in advance according to the management capability of the electronic data, a security level given to each file according to the content thereof, and access record information from each user;
A first step of receiving a request from a user to access a file via the Internet;
A second step of comparing the security level of the requested user with the security level of the requested file;
If the security level of the requested user is lower than the security level of the requested file, access is not permitted and the security level of the requested user is the security level of the requested file. If the file size is larger than the security level, the security level based on the access record is determined from the access level estimated from the security level of the user who made the access request and the access record information from the user and the access pattern of the user who made the access request to the file. The third step of calculating the level,
A fourth step of comparing the security level based on the access results calculated in the third step with the security level of the requested file;
A fifth step of determining whether or not the user who has made the access request is permitted to access the requested file based on the result of the comparison in the fourth step;
In the fifth step, when it is determined that the access is permitted, a sixth step of transmitting the requested file to the client of the user who has requested the access via the Internet,
A data protection method comprising: 10. The data protection method according to claim 9, wherein each of the files is encrypted and transmitted to the client of the user who has made the access request. The data protection method according to claim 10, wherein the encrypted file, the security level of the user, and the security level of the file are stored using a UDF (Universal Disk Format) file system. When it is determined in the fifth step that access of the user who made the access request is not permitted, re-authentication for confirming whether the user who made the access request has the registered access right The authentication means performs the above-mentioned access right, and when it is determined that the access can be permitted, the user who made the access request via the Internet 10. The data protection method according to claim 9, wherein the data is transmitted to the client. In the fifth step, when it is determined that access of the user who has made the access request is not permitted, a result of the determination is notified to an administrator who manages the server system. Item 9. The data protection method according to Item 9. 10. The data protection method according to claim 9, wherein the security level of the user and the security level of the file are provided in an area of the storage device that is not normally accessed from a file system. Obtaining a sector address of an area not normally accessed from the file system, writing information on the user security level and the security level of the file in a sector having the obtained sector address, and reading the written information. The data protection method according to claim 14, wherein: 10. The data protection method according to claim 9, wherein the means for executing the first to sixth steps is loaded via a communication line different from the Internet when executing the data. A program used for data protection in an electronic data exchange system by a server system placed on the Internet, comprising:
Management information holding means for holding a security level given to each user in advance according to the management capability of the electronic data and a security level given to each file according to the content thereof;
Access result information holding means for holding access result information from each user,
The security level of the user is compared with the security level of the file, the access pattern estimated from the security level of the user and the access result information from the user, and the user who has requested access to the file. The security level based on the access record is calculated from the access pattern of the user, and the security level based on the calculated access record is compared with the security level of the file for which the access request is made. Determining means for determining whether or not access to the file for which the access request has been made is permitted;
Transmitting means for transmitting the requested file to the user-side client having made the access request via the Internet, when it is determined by the determining means that access is permitted;
A program characterized by functioning as a program. 18. The program according to claim 17, wherein the program causes the computer to function as encryption processing means for encrypting and decrypting each of the files, and as encrypted content storage means for storing the encrypted files. 19. The program according to claim 18, wherein a UDF (universal disk format) file system is used as an installation location of the encrypted content storage unit and the management information holding unit. When the determining unit determines that the access of the user who has made the access request is not permitted, the computer determines whether the user who has made the access request has the registered access right. Function as an authentication means for performing re-authentication, and when the authentication means has the access right and it is determined that the access can be permitted, the transmission means transmits the requested content via the Internet. 18. The program according to claim 17, wherein the program is transmitted to a client on the user side that has made an access request. The computer functions as notifying means for notifying an administrator managing the server system of a result of the determination when the determining means determines that access of the user who made the access request is not permitted. The program according to claim 17, wherein the program is executed. 18. The program according to claim 17, wherein the management information holding unit is provided in an area that is not normally accessed from a file system.

Images