JP2001155423A - Unauthorized copy protection recording medium - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a recording medium which prevents unauthorized copying of pirated copies and the like. SOLUTION: In a copy source recording medium having a table of contents file size, a dummy file in which a file size larger than the storage capacity of a copy destination recording medium for reading and copying the file size from the table of contents is recorded on the copy source recording medium. Is added.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium for preventing unauthorized copying.

[0002]

2. Description of the Related Art As a logical format standard of a CD-ROM, the ISO9660 standard is known. This ISO
Since the 9660 standard aims at exchanging files with various computers, it is necessary to incorporate a driver that can execute reading on any platform. In other words, the ISO 9660 standard is a common logical format for various computers.

Conventionally, the file size on a CD-ROM is recorded in a directory record on a disk. Since the file size generally matches the length of a real file area, the CD-ROM is copied by reading the file size and the recording address from the table of contents.

[0004]

However, since the file size of an existing file matches the file size recorded in the directory record, copying of a CD-ROM is easy, and illegal copying of pirated or the like is possible. Had a problem of rampant.

Accordingly, an object of the present invention is to provide a recording medium in which illegal copying such as piracy is prevented.

[0006]

In order to achieve the above object, the present invention provides a copy source recording medium having a file size in a table of contents, and reads and copies the file size from the table of contents to the copy source recording medium. An illegal copy prevention recording medium characterized by adding a dummy file recording a file size larger than the storage capacity of the copy destination recording medium.

Further, the recording medium of the copy source is a CD-R
2. The recording medium according to claim 1, wherein the recording medium is an optical disc such as an OM or a CD-R, and the copy destination recording medium is a writable optical disc such as a CD-R.

In the above configuration, since a dummy file recording a file size larger than the storage capacity of the copy destination recording medium is added, the file size is read from the table of contents and copied to the copy destination recording medium. Can be prevented.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. The CD-ROM is usually copied by reading the file size and the recording address from the table of contents. A CD-ROM as a recording medium for preventing unauthorized copying according to an embodiment of the present invention is a CD-ROM from which a file size and a recording address are read from a table of contents and copied.
The ROM is characterized in that a copy destination recording medium, for example, a dummy file that records a file size larger than the storage capacity of the CD-R is added to the copy source CD-ROM.

FIG. 1 is a view showing a method of manufacturing an unauthorized copy protection recording medium according to an embodiment of the present invention. FIG.
As shown in (A), first, a CD-R as a master
An OM ISO9660 image is generated to create an image file. For this, generally, select "Create ISO9660 image" when creating with commercially available writer software. FIG. 3 is a diagram showing the structure of a CD-ROM image.

Next, as shown in FIG. 1B, the image file is operated. In the operation of the image file, first, a file name and a new file size are given. Next, as shown in FIG. 1B, the image file is searched and the file size information of the specified file is rewritten. Next, as shown in FIG. 1C, the changed ISO9660 image is written to the writer.

FIG. 2 is a diagram showing a method of artificially changing a file size for manufacturing an unauthorized copy protection recording medium according to the present invention. As shown in FIG. 2A, first, the primary volume descriptor in the ISO9660 image is read. That is, since the primary volume descriptor is recorded in the area of 00:02:16 in the ISO9660 image, the computer first reads this area.

FIG. 4 is a diagram showing dump data of the primary volume descriptor at 10 (HEX) 00:02:16. Note that (HEX) indicates a hexadecimal notation.

Next, as shown in FIG. 2B, an area in the primary volume descriptor where the path table is recorded is read. In FIG. 4, the L path table 1 is shown at 8c (HEX) to 8f (HEX). It can be seen that the 160000-> 16 (HEX) sector is the path table. In addition, 16 (HEX)
Is 22 in decimal notation. Since 00:02:00 is the start address of the CD-ROM,
It can be seen that the L path table 1 is recorded at 0:02:22.

FIG. 5 is a diagram showing the dump data of the 16 (HEX) path table, and FIG. 6 is a diagram describing this dump data for each table. In FIG.
Is the sector address where the directory record of $ A exists. 1f000000 to 000000001f
In other words, there are 31 sectors 00:02:31. The $ A table refers to Dir number 2. It can be seen that the directory record of \ A exists at 1f (HEX).

Next, as shown in FIG. 2C, the recording address of the directory record is read. That is, by referring to the path table, the recording address of the directory record indicating the directory specified by the absolute path can be known. Next, as shown in FIG. 2D, the file name indicated by the absolute path is searched with reference to the directory record.

FIG. 7 shows dump data of a 1f (HEX) sector directory record. In addition, if (H
EX) is 31 sectors in decimal notation, 00: 0
2:31.

Referring to FIG. It is a directory record table of DAT. As shown in directory record table 3, {A} A. DAT file size "00040000 0000040"
"0" means 1024 bytes.

Next, as shown in FIG. 2E, the file size of the searched file is changed. That is, the file size of the directory record table indicating the specified file is replaced with the specified size. That is, FIG.
{A} of the directory record table 3 shown in FIG.
Set the DAT file size to ffffffffffffff
Rewrite to fff.

In the following, the copy source recording medium is a CD-ROM
An embodiment of changing a file size in a medium which is a disc or a CD-R disc and in which a recorded logical format is logically formatted according to ISO9660 will be described.

This CD-ROM disk is {A} A. D
A file named AT is included, and the file size of the file currently indicates 1024 bytes, but the newly created CD-ROM indicates 4.2 Gbytes (0xffffffff). However, 4.
There is no way that a 2G area can be placed on a CD-ROM disc. 4.2G is just the file size on the directory record and is not actually located.

First, a CD-ROM disk as a master or a CD-R (hereinafter referred to as a disk)
The program end time is read by the D-ROM drive.

Next, from the disc start time 00:02:00 to the end time, the CD-ROM drive reads the disc in sector units (2048 bytes) and outputs it to a file on a large-capacity medium such as a hard disk. Copy this file name to CDROM. IMG.

{A} The location where the directory record for DAT is recorded is indicated by CDROM. Search from inside DAT data. First, the data of the 16th sector primary volume descriptor is stored in the memory. 8c (HEX) to 8f (H
Since the address of the L path table is described in EX), it is read. In this embodiment, it can be seen that the L path table exists in the 16 Hex sector. (See Fig. 4)

The path table is 16 Hex = 32 (DE
C), the 32nd sector is stored in the memory. The data stored in the memory is searched for a path table record described for $ A. Directory ￥
It can be seen that the directory existence address of A is 1f (HEX). (See FIGS. 5 and 6)

The directory record of $ A is 1f (H
ex) Since there are 31 sectors, data of 31 sectors is stored in the memory. A. Search DAT directory records.

In the dump data shown in FIG. DAT
Directory records found. 0000 from this directory record for file size
It can be seen that 0400Hex = 1024 bytes.
This area is changed to 0xffffffff. As a result, the file size is changed from 1024 bytes to 4.2 GB. In FIG. 7, reference numeral 4 indicates a recording address, and reference numeral 5 indicates a file size.

CD-ROM. DAT is {A}. DAT
Is a disk image file whose file size has been corrected. CDROM. CD-R using DAT
Create a CD-R with a writer or the like. CD-R created
Dir command with a personal computer or the like, or {A} A. When the file size of the DAT is confirmed, it has been updated to the new file size.

This disc is set in a computer,
Consider a case where a copy command is used to copy data to another medium. ¥ A ￥ A. DAT data contains 2
5 (HEX) address. Originally 10
Since the file size was 24 bytes, 25 (HE
X) in the address {A} A. DAT is recorded. From this address, the computer uses 0xff
Attempt to copy up to ffffff sector. While the copy is being executed, the program reaches the program end point (lead-out) of this medium before reaching the 0xffffffff sector. CD-ROM is 650M
Only bytes can actually be recorded. The computer accesses the unrecorded, unreadable area and returns an error. Therefore, copying can be prevented.

The present invention is not limited to the above embodiment. For example, as a copy source recording medium, a CD-R
Although the case of OM has been described, the present invention can be applied to other recording media having a file size in the table of contents.
Also, the case where the copy destination recording medium is a CD-R has been described, but the present invention can also be applied to other recording media in which the file size is read from the table of contents and copied. Further, in the above embodiment, the case where one area is changed to 4.2 GB has been described, but a plurality of areas may each be changed to 4.2 GB according to the storage capacity of the copy destination recording medium. .

[0031]

As described above, according to the present invention, there is an effect that it is possible to provide a recording medium in which illegal copying such as piracy is prevented.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a method of manufacturing an unauthorized copy protection recording medium according to an embodiment of the present invention.

FIG. 2 is a diagram showing a method of artificially changing a file size for manufacturing an unauthorized copy protection recording medium according to the present invention.

FIG. 3 is a diagram showing a structure of a CD-ROM image.

FIG. 4 shows the primary volume descriptor 10
It is a figure which shows the dump data of (HEX) 00:02:16.

FIG. 5 is a diagram showing dump data of a path table of 16 (HEX).

6 is a diagram describing the dump data of FIG. 5 for each table.

FIG. 7 is dump data of a 1f (HEX) sector directory record.

[Explanation of symbols]

 1 L path table 2 Sector address 3 Directory record table

Claims (2)

[Claims] 1. A copy source recording medium having a table of contents having a file size, wherein a dummy having a file size larger than the storage capacity of a copy destination recording medium for reading and copying the file size from the table of contents is recorded on the copy source recording medium. An unauthorized copy protection recording medium characterized by having a file added thereto. 2. The copy source recording medium is a CD-RO.
2. The recording medium according to claim 1, wherein the recording medium is an optical disk such as an M or CD-R, and the copy destination recording medium is a writable optical disk such as a CD-R.