JPH036639A - Storage system, file control system, and operating system and information processor adopting the same operating system - Google Patents

Abstract

PURPOSE:To facilitate the protection of secrecy of files by recording the file data in a 1st storage medium and recording the whole or a part of information necessary for access to the file data in a 2nd storage medium respectively. CONSTITUTION:When a 1st storage medium is shared by plural users, each user has his/her own exclusive 2nd storage medium. That is, the file data 8 is directly recorded to an HD 7. While a directory 12 and a FAT 13, i.e., the keys to access files are recorded to another storage medium 11. This medium 11 is controlled by an individual. Consequently, a user except a specific user can not easily access the file data 8 even in an operating system that has no general security function.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a storage system for a storage medium such as a magnetic disk, a file management system and operating system for such a storage medium, and a storage system for such a storage medium. The present invention relates to an information processing device equipped with an operating system. In particular, it relates to a storage method that takes security into consideration for storage media such as hard disks that may be shared by multiple people.

[Prior Art] Information processing devices such as personal computers are generally connected to large-capacity storage devices such as hard disks due to increases in program size and data amount. In addition, unless the equipment is owned by an individual, when using it in an office, etc., from the point of view of effective use of the equipment,
In many cases, a single information processing device is shared by multiple users, and therefore security of internal information such as hard disks has become an issue.

FIG. 5 is a block diagram of an information processing device equipped with a hard disk as a storage device.

In the figure, 1 is a CPU, 2 is a bus, and 3 is a memory.

Inside the memory 3, an operating system (hereinafter abbreviated as O8) 4 and a user program 5 are stored.

A hard disk controller (hereinafter abbreviated as HDC) 6 controls a hard disk (hereinafter abbreviated as HD) 7 . Recorded in the HD 7 are file data 8, a directory 12 in which file names and the like are recorded, and a file allocation table (hereinafter abbreviated as FAT) 13 that indicates the free area 9 and the recording position of the file data 8. There is.

Generally, when the user program 5 accesses the file data 8, it does so via the O84.

○S4 first checks whether the file exists in the HD7 from directory 12, and if so, then
The recording position of the file is determined from 13 and the file data 8 is read out. Thereafter, the file data 8 is converted into a logical file by ○S4.

FIG. 6 is a diagram showing an example of the directory 12 and FAT13.

The directory 12 is divided into several fields, such as file name 14. It is divided into fields such as attribute 15 and first entry 16. F.A.T.
13 has entries 17 for the number of clusters in HD7. In the case of this diagram, the entry number is OOOO(H)
to FFEF (H) (H stands for Hex and is 16
(represents a decimal number).

FIG. 7 is a diagram schematically showing the recording state of the HD7. The concentric recording areas are further divided into smaller sections and managed in units called clusters 18.

- As an example, rEXAMPLE shown in FIG.

I will explain how the file DOCJ is recorded on the HD7.

First entry 1 of this file in directory 12
6 is 0.003 (H), which indicates that the file is recorded from the third cluster 18.

Next, if you look at the third entry 17 of FAT13, it will be 0O
It is OA(H). Therefore, the following data is written in the tenth cluster 18. Following the chain in this way, the last cluster 18 is the entry 17 in which the data representing the end of the file, in this example F F F F (H), is found.

In this way, the file entrance to directory 12 is
In the FAT 13, so-called position information indicating how data is recorded in the cluster 18 is recorded.

Note that the entry 17 records not only the positional relationship of the files but also the free area 9 shown in FIG. 5. For example, if the value of entry 17 is 0000 (H), this indicates that the cluster is unused and is empty area 9.

An example of such a directory 12 and FAT 13 is disclosed in Natsume Publishing, "rMS-DO5 Structural Analysis" by Takayoshi Oshino, pages 30 to 40.

[Problems to be Solved by the Invention] Conventionally, in such devices, in order to maintain security by restricting access to files, methods for recognizing individuals using passwords and adding attributes of access permission to files have been used. They use methods that only allow certain people to see it. An example of this is discussed in "PC Security J" by Keigaku Publishing, H. J. Hyland, pages 109 to 150.

However, such a security method requires changing the S4, which manages files, from supporting multiple users to being suitable for the security method, which poses a problem in terms of compatibility. If you use a password etc.
An operator is required to register and manage the passwords, which is a heavy burden on small-scale systems.

Further, no matter how well managed, since the directory 12, FAT 13, and file data 8 are recorded together on the HD 7, there is a risk that this information may be read out by a special program or the like. Alternatively, there is a risk that an operator who can access all files may at least be accessed.

A first object of the present invention is to provide a storage system that easily prevents file data from being accessed by anyone other than a specific user, even in an operating system that does not have a digital security function.

A second object of the present invention is to provide a file management system that allows access for each user even when there are 'Pi users.

Furthermore, a third object of the present invention is to provide an operating system that makes it possible to share a storage medium while restricting file access by users other than specific users, and an information processing device equipped with such an operating system. It's about doing.

[Means for Solving the Problems] The first object is to include at least a first storage medium and a second storage medium, record file data on the first storage medium, and provide access to the file data. This is achieved by recording all or part of the necessary information on a second storage medium.

The object includes at least a first storage medium and a second storage medium, records file data in the first storage medium, and stores all or part of information necessary for accessing the file data in the second storage medium. While recording on the storage medium, the first
When the content of the storage medium is updated, update date and time data is recorded in the first and second storage media, and when the content of the first storage medium is then updated, the first and second storage media are updated. This can also be achieved by validating information necessary for accessing the file data recorded in the second storage medium when the date and time data recorded in the second storage medium are equal.

A second object of the present invention is to record file data using a storage medium that can be shared by multiple people as a first storage medium,
All or part of the information necessary for accessing the file data is recorded in a different second storage medium for each user who stored the file data in the first storage medium, and when reading the file data, the information necessary for accessing the file data is recorded in a different second storage medium. This is achieved by a solution that reads the target file data from the first storage medium by referring to information necessary for accessing the file data from the second storage medium of the file data user.

The third object is an operating system for an information processing Mffi that has a storage medium that can be shared by multiple people, and the shared storage medium is
As a storage medium, it has a function of recording file data and recording all or part of the information necessary for accessing the file data in a second storage medium, and when reading file data, it has a function of recording file data and recording all or part of the information necessary for accessing the file data. This is achieved by a device that manages files and has a function of reading the target file data from the first storage medium by referring to necessary information.

Further, the third object is to configure an information processing device that is equipped with a storage device that drives the first and second storage media, a function that processes data, and is equipped with the operating system. This is achieved by

Preferably, the operating system has a function of randomly setting a recording area when recording file data on the first storage medium.

The operating system also has a function of recording update date and time data in the first and second storage media when the content of the first storage medium is updated, and then updating the content of the first storage medium. When the date and time data recorded in the first and second storage media are equal,
Preferably, the second storage medium has a function of validating information necessary for accessing the file data recorded on the second storage medium.

The first storage medium has a recording area divided into a plurality of unit recording areas, and is configured to record file data by dividing it into the unit recording areas, and is configured to record whether or not each unit recording area is in use. Preferably, a table for displaying the information is provided. As a unit recording area, for example, cluster, sector,
Examples include trucks. An example of this first storage medium is a hard disk. Of course, the present invention is not limited to this, and may be a one-time storage medium as long as it can be shared by multiple people. Examples include optical disks, floppy disks, and the like.

Further, it is preferable that the second storage medium is portable. In other words, a drive device that actively drives the storage medium or an information processing device that includes this drive device,
Preferably, the storage medium is removable and can be removed from the device when not in use. This is because the user of the second storage medium can personally manage it and security can be easily ensured.

The information required to access the file data is as follows:
For example, there is information indicating whether or not the file data is recorded in the first storage medium, and information indicating the recording position of the file data in the first storage medium.

For the former, e.g.

There is a directory. The latter includes, for example, file allocation information.

In the present invention, either the information indicating the presence or absence of recording in the first storage medium or the information indicating the recording position in the first storage medium may be recorded on the second recording medium, but preferably , record both. This increases the effect of suppressing access by persons other than the specified person.

It is sufficient to store the information necessary for accessing the file data in the second storage medium only for the file data that needs to be excluded from access by others. The data may be stored in the first storage medium.

[Function] The present invention has been made based on the fact that information such as directories and file allocation information is required to access file data recorded on a storage medium.

That is, in the present invention, at least a first storage medium and a second storage medium are provided as storage media, file data is recorded in the first storage medium, and all or all of the information necessary for accessing the file data is recorded. By recording a portion of the file data on the second storage medium, the target file data cannot be accessed using only the storage medium that stores the file data.

Therefore, when a first storage medium is shared by multiple people, each user has their own second storage medium and manages this to prevent others from accessing each person's files. be able to. Moreover, since the second storage medium can be managed personally, the above-mentioned problem when setting a password can be avoided.

The operation of the present invention will be explained in more detail with reference to FIG. In the following, a hard disk is used as the first storage medium, a floppy disk is used as the second storage medium, and directory and file allocation information are used as the information necessary to access file data. There is. Further, the file allocation information is configured as a file allocation table (FAT).

In the present invention, the file data 8 is recorded as it is on the HD 7, but at least one of the directory 12 and the FAT 13 (which can be called the key for accessing the file) (both in FIG. 1) is recorded on a separate storage medium. By individually managing a separate storage medium, it is possible to share the HD 7 while taking security into consideration.

Also, in this case, if multiple storage media that record only directory 12 and/or FAT13 information of files that each user can access are divided for each user, and FAT13 is not recorded on the HD7, instead , by providing another table showing the free areas 9, the danger of double use of storage areas can be reliably avoided.

If both the directory 12 and the FAT 13 are not aligned, the file data 8 is just a data string, and it is very difficult to analyze it even if it is directly read. Therefore,
For example, if at least one of the directory 12 and FAT 13 is recorded on a removable and portable storage medium such as a floppy disk, and the file administrator stores it, other people will not be able to access the file data 8. become unable.

Further, if this is done, if there are multiple users, multiple directories 12 and FATs 13 will exist, and it may become impossible to centrally manage the HD7. In that case, a new table may be provided in the HD 7 to record only the usage status of unit recording areas such as the cluster 18.

It is also conceivable to make a backup copy of the storage medium containing the directory 12 and/or FAT13. In this case, an old directory 12 and/or FAT 13 from a previous backup and a current directory 12 and/or FAT 13 will exist. this is.

HD7 and floppy disk (hereinafter abbreviated as FD) 11
You can prevent erroneous access by recording the last date and time of the change and determining that it is valid only when the two dates and times match.

(Margin below) [Example] Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an example of an information processing apparatus to which a first embodiment of the present invention is applied.

The information processing device shown in the figure includes a CPtJl, a memory 3, an HDC (hard disk controller) 6, and an FDC.
(floppy disk controller) 1o is connected to path 2.

The memory 3 stores an O8 (operating system) 4 and a user program 5. these are,
Executed by CPUI.

HD7 is connected to HDC6. In this embodiment, only file data 8 is stored in the HD 7. Therefore, file data 8 and empty area 9 exist within the HDT.

Furthermore, FDII is connected to FDCIO. A directory 12 and FAT 13 are stored in this FDII. In this embodiment, the directory 12 and FAT for all file data of the user are
13 is stored in FDII.

In addition to the functions generally executed in an information processing device, 054 has a function of recording file data on the shared HD 7 and recording the directory 12 and FAT 13 on the FDII as information necessary for accessing this file data. When reading file data, it has a function of reading the target file data from the HD 7 by referring to the directory 12 and FAT 13.

In this embodiment, this 084 is used to manage files on the HD 7 that can be shared by multiple people.

Next, the operation of this embodiment will be explained.

First, when Rtaing new file data to the HD 6, the O84 first registers the file data in the directory 12 of the FDII.

Then, referring to the FAT13 of the FDll, file data is sequentially stored in unused clusters. Additionally, the O84 registers the location where the file data is stored in the FAT13.

Next, when trying to access a file,
○S4 reads directory 12 from FDII,
Next, read FAT13 to find out the storage location of the file data. Then, according to this information, the target file data is read out from the HD 7.

By the way, if another user tries to access file data that is not under their control.

Even if the O34 tries to read the file data according to the procedure described above, the directory 12 indicating the existence of the target file data and its storage location is not displayed.
and in the absence of FDII with FATL3, H
Since the information necessary for access cannot be provided to the DC 6, it cannot be read. In this case, since the presence or absence of file data and the storage location are unknown, the security of this file data is ensured.

Note that in this embodiment, directory 12 and FAT1
3, the read destination is simply replaced from HD7 to FDII, so existing O8 without security function
This can be done with just a few changes. Of course, when developing a new O8, security functions can be easily added.

Next, a second embodiment of the present invention will be described.

In addition, regarding the embodiments following this second embodiment.

Since the basic configuration of the information processing apparatus to which this embodiment is applied is the same as that of the first embodiment, the explanation will focus on the differences and will not repeat the explanation of the overlapping parts.

FIG. 2 shows an example of the configuration of an information processing apparatus to which a second embodiment of the present invention is applied.

As shown in FIG. 2, in this embodiment, FDlla and llb are prepared to accommodate a plurality of users (two in this embodiment). Directory 1'2a and FAT13a are provided in FDlla, and directory 12b and FAT13)) are provided in llb.

Further, in addition to the data 8 similar to the first embodiment, the HD 7 is provided with a usage cluster table 19 as a table indicating whether each unit recording area is in use. 19 has FAT13a
Data obtained by logical sum of the usage status of FAT13b and FAT13b is recorded.

FIG. 3 shows this usage cluster table 19 and FAT1
3a and FAT 13 b are shown.

As shown in the figure, between FAT13a and FAT13b,
For the used cluster 18, 1, for example, FFFF (H) is written in the entry 17c of the used cluster table 19 as a used mark. On the other hand, unused entry 17a has an unused mark of 0000 (
Let it be H).

The O S4 of this embodiment has the function of managing the used cluster table 19 described above in addition to the functions of the O84 of the first embodiment.

Next, the operation of this embodiment will be explained.

If there are a plurality of users, there will be a plurality of FDlls, that is, a plurality of directories 12 and FATs 13 (two in this figure) corresponding to each user. In this case, a certain user
Using Dlla.

When free space 9 of HD7 is newly used, entry 17a of FAT13a corresponding to used cluster 18
is rewritten from 0000 (H) indicating unused to a valid entry number. However, since the FA'T 13b of the FDllb kept by the other user is still unused, a problem arises in that the usage statuses of the two users do not match.

In contrast, this embodiment deals with this by recording the logical sum of the usage status of clusters by each user in the usage cluster table 19, as described above. That is, when the O84 newly uses the free area 9, it not only marks the entry 17 of the FAT13 of the inserted FDII as used, but also marks the entry 17c of the used cluster table 19 as used. (
H).

As a result, when newly writing file data to the HD 7, the O34 detects the cluster unused mark 0000 (H) in the used cluster table 19, writes the file data to the cluster concerned, and also writes the data. For clusters, the above-described processing is performed. As a result, even if a plurality of users individually write data, data will not be written twice to a cluster used by another person. Therefore, malfunctions can be prevented.

Next, a third example of this example will be described.

FIG. 4 shows a configuration example of an information processing apparatus to which a third embodiment of the present invention is applied.

In this embodiment, as shown in FIG. 4, a clock circuit 20 that is constantly operated by a battery such as a dry battery is connected to the bus 2. Further, the HD 7 is provided with a date field 21, and the FDll is provided with a date field [-22. The date and time when FAT13 was updated is recorded in this day's size fee JREDO 21.22. This date and time is set by the clock circuit 20.

In addition to the functions of the S4 of the first embodiment, the ○S4 of this embodiment has a function of recording update date and time data in the date fields 21 and 22 when the contents of the HD7 are updated, and When updating the contents, when the date and time data recorded in the date fields 21 and 22 are equal, the FD 11 has a function of validating the directory 12 and FAT 13 recorded in the FD 11.

Next, the operation of this embodiment will be explained.

In this embodiment, similarly to the first embodiment described above,
File data can be managed.

By the way, some users may consider making a backup copy of the FDll. In that case, the old FDII that was previously backed up and the latest FDII that is currently in use may end up being the same.

On the other hand, in this embodiment, when the HD 7 is updated, the update date is obtained from the clock circuit 20 by O34 and recorded in the date field 21.22. The date field 22 in which this date and time is recorded is that of the FDIl currently being marked by the FDCIO. Therefore, at this time, this data is not recorded in the date field 22 of the backup-copied FDll that is not activated.

On the other hand, when accessing the file data recorded on the HD7, the O34 compares the date field 22 of FDI:L currently being updated by the FDC, IO with the date field 1-21 of the HD7. , it is checked whether the two match, and only the matching FDII is validated. This distinguishes between the latest FDll and the old FDII.

In addition, if there are multiple users, it is sufficient to provide a date field 21 for each file and check whether it matches the date field 22 of the corresponding FDII.In each of the embodiments described above, FAT13 is recorded. Although we have explained the case where FDII is used as the storage medium, other ICs may also be used.
Any removable medium such as a card or removable hard disk will do.6 Also, in some areas of the HD7,
It is also possible to provide the directory 12 and FAT 13 as a common area as before, and apply the present invention to the remaining areas to protect individual areas.

Furthermore, if the file data 8 is recorded on the HD 7 in consecutive clusters 18, the contents may be guessed even without the FAT 13, so the data may be recorded randomly.

Further, the directory 12 and FAT 13 recorded in the FDII may be transferred to the memory 3 when the FDI 1 is installed in order to speed up access to the file data 8.

Furthermore, the HD 7 and the FDII do not need to be on the same bus 2; for example, the HD 7 may be provided by another information processing device via a network.

In addition, by combining the present invention and conventional passwords,
Furthermore, security may be strengthened.

[Effects of the Invention] As explained above, according to the present invention, each user manages directory information, FAT information, etc. necessary for accessing files, so file confidentiality can be easily protected. This has the effect of maintaining security even when there are multiple users.

Moreover, not only can the conventional O8 be used with a slight modification, but it also has the effect of not changing the ease of use for experienced users.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of an information processing device to which the first embodiment of the present invention is applied, and FIG. 2 is a block diagram showing an example of the information processing device to which the second embodiment of the invention is applied. 3 is an explanatory diagram of the cluster table used in the second embodiment, FIG. 4 is a block diagram showing an example of an information processing apparatus to which the third embodiment of the present invention is applied, and FIG. 5 is a conventional 6 is a block diagram of the storage device of the directory and F
An explanatory diagram of AT, and FIG. 7 is an explanatory diagram of HD. 1.CPU, 2.Bus, 3.Memory, 4..O
8, 5...User program, 6...HDC17...
・HD, 8...File data, 9...Free area,
10...FDCll...FD, 12...Directory, 13...FAT, 14...File name, 15
・Attribute, 16・1st entry, 17...Entry, 1
8...Cluster, 19...Used cluster table, 2
0...Clock circuit, 21.22.Date field.

Claims (1)

[Claims] 1. At least a first storage medium and a second storage medium are provided, file data is recorded in the first storage medium, and all or part of the information necessary for accessing the file data is provided. A storage method characterized by recording on a second storage medium. 2. Comprising at least a first storage medium and a second storage medium, file data is recorded in the first storage medium, and all or part of the information necessary for accessing the file data is stored in the second storage medium. At the same time, when the contents of the first storage medium are updated, update date and time data is recorded on the first and second storage media, and then when the contents of the first storage medium are updated, the When the date and time data recorded on the first and second storage media are equal, information necessary for accessing the file data recorded on the second storage medium is validated. method. 3. A file management method for an information processing device having a storage medium that can be shared by multiple people, wherein file data is recorded using the shared storage medium as a first storage medium, and information necessary for accessing the file data is recorded. All or part of the information is recorded in a second storage medium that is different for each user who has stored the file data in the first storage medium, and when reading the file data, the second storage medium of the user of the file data is recorded. with reference to the information necessary for accessing the file data from the storage medium of the first
A file management method characterized by reading target file data from a storage medium. 4. An operating system for an information processing device having a storage medium that can be shared by multiple people, the shared storage medium being used as a first storage medium to record file data, and providing information necessary for accessing the file data. A function for recording all or part of the information on the second storage medium, and when reading file data, referring to the information necessary for accessing the file data, reading the target file from the first storage medium. An operating system characterized by having a function for reading data and managing files. 5. The operating system according to claim 4, further comprising a function of randomly setting a recording area when recording file data on the first storage medium. 6. A function for recording update date and time data in the first and second storage media when the content of the first storage medium is updated; Claim comprising a function of validating information necessary for accessing the file data recorded in the second storage medium when the date and time data recorded in the first and second storage media are equal. The operating system according to item 4 or 5. 7. a storage device that drives the first and second storage media;
Claim 4 further comprising a function of processing data.
, 5 or 6. An information processing device equipped with the operating system described in . 8. The first storage medium has a recording area divided into a plurality of unit recording areas, and is configured to record file data divided into unit recording areas, and whether each unit recording area is in use or not. Claim 1 further comprising a table representing the
or the storage method according to claim 2, the file management method according to claim 3, the operating system according to claim 4, 5 or 6, or the information processing apparatus according to claim 7. 9. The storage method according to claim 1 or 2, the file management method according to claim 3, or the operating system according to claim 4, 5 or 6, wherein the second storage medium is portable, or 8. The information processing device according to claim 7.