JP4277704B2 - Information recording apparatus, information reproducing apparatus, information recording / reproducing apparatus, information recording method, and recording medium - Google Patents

Description

  The present invention is suitable for recording and reproducing information such as a CD-ROM (Compact Disc Read Only Memory) system, for example. Information recording apparatus, information reproducing apparatus, information recording / reproducing apparatus, information recording method, and information thereof Relates to a recording medium on which is recorded.

  2. Description of the Related Art Conventionally, in a recording medium such as a disk or a hard disk, content data recorded in a user area is managed by management information recorded in a management information area. For this reason, when playing back a file recorded on this type of recording medium, the recording position information of the corresponding file is acquired from the recorded contents of this management information area, and recorded on the recording medium based on this recording position information. The corresponding file is being played.

  For example, when an application program provided by a CD-ROM is installed in a computer, the setup file recorded on the CD-ROM is executed by executing the setup file recorded on the CD-ROM. The files are sequentially decompressed and recorded on the hard disk device of the computer.

  In installing such an application program, there is a method of preventing illegal copying of the application program by inputting a serial number or the like provided separately. In addition to the above methods, various methods have been proposed as methods for preventing illegal copying. For example, a method has been proposed in which each file of content data is encrypted, and each file corresponding to key information necessary for decryption of each file is recorded on a recording medium such as a CD-ROM (for example, (See Patent Document 1).

As described in Patent Document 1, a file with a content key in which key information necessary for decryption is recorded is, for example, a so-called authoring studio in a stage before manufacturing a CD-ROM at a CD-ROM manufacturing factory. In this case, a file to be encrypted, an encryption method, and the like are determined according to the content data when the content data is created, and recorded together with the content data on a recording medium for supplying the content data. Then, in the CD-ROM manufacturing factory, the content data-added file is read together with the content data from the content data supply recording medium, the content data is encrypted using the read content key-added file, and the content is decrypted. Generally, it is recorded on a CD-ROM as an encrypted content file to which a keyed file is added.
JP 2002-74835 A

  However, the above-described method for preventing illegal copying by inputting a serial number or the like has a problem that management of the serial number or the like is complicated. Further, the one described in Patent Document 1 solves the problem caused by the illegal copy prevention method by inputting a serial number or the like. However, even when recording key information or the like, it can be recorded in the management information area. Since key information can be easily found based on this, there is a problem that sufficient security cannot be ensured.

  In order to prevent illegal copying of content data recorded on a recording medium such as a CD-ROM, it is important that the structure of the content key defined by the format of the recording medium cannot be easily analyzed. In the conventional method for preventing illegal copying as described in No. 1, since all the security information is managed by the authoring studio at the time of content data creation, there is a risk that the format security mechanism may leak from the authoring studio. There was a problem that there was.

In view of the above, the present invention improves the security of information recorded on a recording medium as compared with the conventional one by simple management, and leaks a security mechanism from an authoring studio other than the recording medium manufacturing factory. the information recording apparatus capable of preventing the information recording and reproducing apparatus, it is an object to propose an information recording how.

  In order to solve the above-mentioned problems and achieve the object of the present invention, an information recording apparatus of the present invention performs a predetermined modulation process on content data composed of a content file group provided by a content data supply source, and a recording medium An information recording device for recording information on a content key, and a volume structure is constructed from a content file group and a content key generation information file having information relating to the encryption processing of the content file group, and management information based on the volume structure The volume structure construction unit generates a first content key necessary for processing the content file to be encrypted based on the content key generation information file and records content data as a recording signal. The content file to be encrypted from the information obtained in the process of conversion to A second content key necessary for the processing of the content file is generated, the content file to be encrypted is encrypted with the first and second content keys, and the content file group and the first content key encrypted together with the management information are predetermined. And the second content key is recorded in a predetermined area of the recording medium that is not managed by the management information.

  The volume structure construction unit of the information recording device includes a content key information extraction unit that extracts information on the first content key from the content key generation information file, and a process of converting content data into a recording signal. The encrypted data information detecting unit for detecting information to be used as the second content key, the first content key information extracted by the content key information extracting unit, and the encrypted data information detecting unit Based on the information used as the second content key, a content key generation unit that generates a first content key and a second content key by a predetermined calculation, and the first and second content keys An encryption processing unit for encrypting a content file, a file including a first content key, and a second content key Characterized in that it comprises an encryption processing file generation unit which generates a file containing the distribution.

  According to the present invention, in addition to the first content key generated based on the content key generation information file provided from the content data supply source, the information obtained in the process of converting the content data into the recording signal is used. Since the second content key is generated, the encrypted content file group and the first content key are recorded together with the management information, and the second content key is recorded in a predetermined area of the recording medium that is not managed by the management information. Therefore, it is possible to prevent the content key from being acquired even if the management information is read for a device having a file system that does not support the format of the recording medium.

  In addition to the first content key generated based on the content key generation information file provided from the content data supply source, the second content key is automatically set by information obtained in the process of converting the content data into a recording signal. Since it is generated, the content key necessary for decrypting the encrypted content file at the time of reproduction is increased, and the security of information recorded on the recording medium is improved. Furthermore, since the second content key is generated based on the information obtained in the process of converting the content data into the recording signal, the recording medium manufacturer can set and manage the content key independently.

  In addition, as a preferred embodiment, the information recording apparatus described above generates encrypted data including the second content key to be recorded in a predetermined area that is not managed by the management information of the recording medium, and relates to the second content key. Position information indicating a position where the second content key in the encrypted data is recorded is recorded in a file including the information.

  According to the present invention, the second content key is recorded in a predetermined area that is not managed by the management information of the recording medium, and the recording position information of the second content key is obtained from the file in which the information related to the second content key is recorded. As a result, since the second content key recorded in the encrypted data can be acquired based on the position information, a multi-stage process is required until the content key is acquired at the time of reproduction, and the security of the recording medium is further increased. Can be improved.

  The information recording / reproducing apparatus of the present invention has a volume structure from a content file group constituting content data provided from a content data supply source and a content key generation information file having information related to encryption processing of the content file group. And a volume structure constructing unit that creates management information based on the volume structure, and the volume structure constructing unit includes the first content necessary for processing the content file to be encrypted based on the content key generation information file. A key is generated, and a second content key necessary for processing the content file to be encrypted is generated from information obtained in the process of converting the content data into a recording signal, and encrypted using the first and second content keys. Encrypt the content file to be encrypted, and The content file group encrypted together with the physical information and the first content key are subjected to predetermined modulation processing and recorded on a recording medium, and the second content key is recorded on a predetermined area of the recording medium that is not managed by the management information Analyzing the recording device, the encryption detecting means for detecting that the content file group recorded on the recording medium is encrypted, the file including the first content key and the file including the information related to the second content key And decrypting the content file to be encrypted using the first content key and the second content key obtained by the cryptographic analysis means. And a playback device for playback.

  An information recording method of the present invention is an information recording method for performing a predetermined modulation process on content data configured from a content file group provided by a content data supply source and recording the content data on a recording medium. Based on the content key generation information file, a volume structure construction step for constructing a volume structure from the content key generation information file having information related to the encryption processing of the content file group and creating management information based on the volume structure A first content key required for processing the content file to be encrypted is generated, and a second content key required for processing the content file to be encrypted is generated from information obtained in the process of converting the content data into a recording signal. And the first and second content keys A volume structure conversion step for encrypting the content file to be encrypted, adding the first and second content keys to the volume structure, deleting the content key generation information file, and converting the volume structure; The content file group encrypted together with the management information and the first content key are subjected to a predetermined modulation process and recorded on a recording medium, and the second content key is recorded on a predetermined area of the recording medium that is not managed by the management information It is characterized by.

  According to the present invention, the first content key created based on the information in the content key generation information file provided from the content data supply source when the recording medium is manufactured, and the signal for recording the content data when the recording medium is manufactured Since the encrypted content file is decrypted with the second content key created based on the information obtained in the process of converting to, multiple content keys are required, improving the security of the recording medium can do. Further, since the second content key is generated based on information obtained in the process of converting the content data into the recording signal, the recording medium manufacturer can set the content key independently.

  According to the present invention, since the encrypted data in which the recording position information of the second content key is recorded is recorded in the predetermined area that is not managed by the management information of the recording medium, it corresponds to the format of the recording medium. An information reproducing apparatus that does not have the second content key cannot be obtained by simply reading the management information. Further, by analyzing the file in which the recording position information of the second content key is recorded on the recording medium and then acquiring the second content key based on the recording position information, the decryption is performed. Further, since multiple stages of processing are required, the security of the recording medium can be further improved.

  According to the present invention, an information recording apparatus in a process of recording provided content data on a recording medium separately from a normal content key generated based on a content key generation information file provided from a content data supply source. The content key is generated in the memory, and the content key is recorded in a predetermined area that is not managed by the management information of the recording medium, thereby preventing reproduction by an information reproducing apparatus that does not support the format of the recording medium. In addition, since it is not necessary to separately manage and distribute data used for general copy protection, there is an effect that security of the recording medium is improved by simple management.

  Further, according to the present invention, information is provided in the process of recording the provided content data on the recording medium separately from the normal content key generated based on the content key generation information file provided from the content data supply source. By generating the content key in the recording device, when reproducing the recording medium, both the content key based on the content key generation information file and the content key uniquely created by the information recording device are required. There is an effect that security of the recording medium is improved by simple management. In addition, since the content key is automatically generated in the information recording apparatus, there is an effect that it is possible to prevent leakage of information related to encryption processing to those other than those related to the recording medium manufacture.

  Hereinafter, an example of an embodiment of an information recording apparatus of the present invention and an information recording method performed by the information recording apparatus will be described with reference to FIGS. One embodiment described below is an example applied to creation of a master disc of a CD-ROM system.

  FIG. 1 is a block diagram showing a configuration of a disc master creating apparatus according to an embodiment of an information recording apparatus of the present invention. The disc master creating apparatus 1 uses, as digital data material information (also referred to as content), an optical disc (digital data supply source) 2 on which, for example, an application program is recorded, and information supplied from the optical disc 2 to the disc master 12. A formatter that builds a volume structure of information to be recorded to create management information, reads out the management information and files recorded on the optical disc 2 in order, performs predetermined modulation processing, and outputs a modulation signal to the cutting machine 4 And a cutting machine (exposure device) 4 for irradiating a disk master 12 having a resist coated on the surface thereof according to a modulation signal supplied from the formatter 3. The cutting machine 4 irradiates the disc master 12 with a laser beam and exposes it, and then develops the master disc 12 to create a mother disc. Then, a stamper is created from this mother disk, and a CD-ROM is created using the stamper.

  On the optical disk 2 on which the digital data material information is recorded, content data 5 such as a file related to an application program provided to a user by a CD-ROM, information related to a content key, information such as a flag indicating the presence or absence of encryption, and the like The information file (content key generation information file) 6 necessary for creating the master disc 12 used in the manufacturing process of the CD-ROM including is recorded, and this information is provided to the formatter 3. The content key is information necessary for processing such as playback of the content file constituting the content data. In this example, a part of the content file recorded on the CD-ROM is decompressed or decrypted using this content key. Is to be equal.

  The dedicated device driver 7 which is a component of the formatter 3 in the disc master production apparatus 1 shown in FIG. 1 reads out the optical unevenness data carved on the optical disc 2 of the above-mentioned content data supply source in a non-contact manner. And sent to the volume structure construction unit 8.

  The volume structure constructing unit 8 constructs a volume structure of the CD-ROM from the content file provided from the optical disc 2 and an information file including data necessary for creating the CD-ROM. Also, the management information generation unit 8a provided in the volume structure construction unit 8 generates management information for managing information recorded on the CD-ROM based on the volume structure, and generates an EFM (Eight to Fourteen Modulation) signal. It is output to the circuit 9. The management information generated here is information used when reproducing a file recorded on a CD-ROM. In this example, a bridge format between ISO (International Organization for Standardization) 9660 and UDF (Universal Disk Format) is used. Created in accordance with the provisions of Note that the volume structure construction unit 8 is constituted by arithmetic processing means (not shown) provided in the formatter 3, for example, according to a program to be executed by the arithmetic processing means recorded in a read only memory (ROM) not shown. Predetermined control and calculation are performed while using an access memory (RAM) as a work area.

  Further, the formatter 3 uses an EFM signal generation circuit 9 that performs EFM modulation on a signal based on the volume structure constructed by the volume structure construction unit 8, and a signal that has been EFM modulated by the EFM signal generation circuit 9 as a predetermined clock. An EFM signal output circuit 10 for outputting to the cutting machine 4 as a synchronized modulation signal is provided. The formatter 3 composed of these components corresponds to the pit string created on the disc master 12 by sequentially reading and processing the management information obtained from the volume structure construction unit 8 and the files provided from the optical disc 2. A modulation signal whose signal level is switched is generated.

  Further, the cutting machine 4 of the disk master production apparatus 1 includes a laser drive circuit 11, and a laser that is applied to the disk master 12 according to the modulation signal output from the EFM signal output circuit 10 of the formatter 3 by the laser drive circuit 11. Controls on / off of the beam.

  FIG. 2 is a diagram showing an example of a volume structure defined by the ISO9660 and UDF bridge format. In this rule, the CD-ROM is assigned management information including a system area, a volume descriptor group, a path table group, and a directory record group in order from the top, and a file group.

  The system area is an area of the first 16 clusters allocated for system management. The volume descriptor group is assigned a predetermined number of volume descriptors that are structures of one sector, and information related to the volume such as the creator, the location of the root directory, and boot information is assigned to the volume descriptor. A plurality of path tables are assigned to the path table group. This path table is a table in which directory information is recorded for high-speed directory search.

  In addition, information on files and subdirectories is recorded in the directory record group, and a recording position of each file, a file name, a data length, a file flag, and the like are assigned. The directory record also records information indicating file attributes such as file recording date and protection information.

  FIG. 3 is a diagram showing an outline of volume structure conversion performed by the disc master creating apparatus 1 of this example. In general, in the creation of content data in the authoring studio 20, the information file 6 related to the instruction information of the CD-ROM generation method including the content key generation is edited together with the content data and recorded on the optical disk 2 (see FIG. 1) of the content data supply source. Is done. As described above, the information for generating the content key is provided as the information file 6 from the authoring studio 20 outside the disc master creating apparatus 1.

  However, managing all content keys by the authoring studio 20 is not strong in terms of the possibility of leakage of encryption information. Therefore, in this example, a unique content key is generated by a predetermined process in the formatter 3 of the disc master creating apparatus 1 in a CD-ROM manufacturing factory. Then, the encryption data is generated from the content key, and a file for analyzing the contents of the encryption data is created, added to the volume of the CD-ROM, and recorded.

As shown in FIG. 3, in the authoring studio 20, a volume structure 30 composed of content data (content file group) 5 and information file 6 provided to the user by the content provider is constructed, and the optical disk 2 of the content data supply source is constructed. To record. Then, in the CD-ROM manufacturing factory, the formatter 3 reads the data in which the content file group, the information file 6 and the like are recorded from the optical disc 2, and constructs the volume structure 40. At this time, the encryption processing file 44 is created and automatically added to the volume structure 40. The information file 6 is intended to instruct the generation method of the CD-ROM including the content key generation. Therefore, the information file 6 becomes unnecessary after the volume structure is constructed, and the EFM signal output circuit 9 in FIG. It is not input and is deleted from the file system. As described above, the area (volume) on the disc is recorded so that the file management information 31 after conversion, the content file group 43 (content files A ′, B ′), the content key file group 45, and the encrypted data analysis file 46 are recorded. Build structure 40).

  Here, the content key file group 45 constituting the encryption processing file 44 is a recording of content keys created according to the information in the information file 6 created in the authoring studio 20. On the other hand, the encryption data analysis file 46 has information related to the content key uniquely generated in the formatter 3 of the disc master creating apparatus 1 separately from the encryption processing information managed by the authoring studio 20. That is, position information indicating the recording position of the content key in the encrypted data recorded so that it cannot be reproduced simply by reading management information described later is recorded.

  As described above, the disc master creating apparatus 1 of the present example has a new original content in the CD-ROM manufacturing factory, apart from the content key file group 45 created according to the contents of the information file 6 provided from the authoring studio 20. Try to create a key.

  FIG. 4 is a diagram for more specifically explaining the outline of the volume structure conversion shown in FIG. As shown in FIG. 4, the volume structure construction unit 8 (FIG. 1) constituting the formatter 3 of the disc master creating apparatus 1 includes a content key information extraction unit 51, an encrypted data information detection unit 52, a content key generation unit 53, An encryption processing file generation unit 54 and an encryption processing unit 55 are provided, which are constituted by arithmetic processing means (not shown) provided in the formatter 3 together with the management information generation unit 8a of FIG.

  4 extracts the content file to be encrypted from the content file group 33 provided from the disk 2 based on the information in the information file 6, and encrypts the content file. This is to extract an encryption processing method for this purpose.

  The encrypted data information detection unit 52 detects information serving as a content key necessary for encrypting the provided content data, and uses this information to encrypt the content file to be encrypted by the information file 6. The encryption processing is performed in an encryption processing unit 55 described later. In this example, the logical address of the end 33a of the content file group 33 is calculated, and the calculated final address information is used for generating a unique content key different from the content key generated based on the information file 6. ing.

  In addition, the content key generation unit 53 performs a predetermined calculation process on the content key information supplied from the content key information extraction unit 51 to generate a content key, and also adds predetermined information to the information supplied from the encrypted data information detection unit 52. The content key is generated by performing the above calculation process.

  Further, the encryption processing file generation unit 54 generates the content key file group 45 from the content key created based on the information file 6 sent from the content key generation unit 53 and the encryption data information detection unit 52. The encryption data analysis file 46 is generated from the content key created from the information calculated in step (b). The content key file group 45 and the encrypted data analysis file 46 generated by the encryption processing file generation unit 55 are added to the converted volume 40.

  The encryption processing unit 55 uses a content key generated by the content key generation unit 53 based on the information file 6 or a content key generated from information calculated by the information detection unit for encrypted data 52. Then, the encryption target content file of the content file group 33 is encrypted, converted into the encrypted content file group 43, and added to the volume 40.

  In this example, the content key created based on the information detected by the encrypted data information detection unit 52 is recorded in the predetermined area of the master disk 12 as encrypted data, and the content key in the encrypted data is stored in the encrypted data. Position information indicating the recorded position is recorded in the encrypted data analysis file. The position information is position information on the disk and is represented by a physical address.

  FIG. 5 is a diagram showing an example of the area structure of a single session CD-ROM as an example in order to explain the position where the encrypted data is recorded. A track for encrypted data is provided outside the lead-out area of the disk. The encrypted data including the content keys n + 1, n + 2,..., N + m−1, n + m (n and m are natural numbers) are converted into EFM signals by the EFM signal generation circuit 9 of the formatter 3 in the same manner as the file system, and read out. The data is sequentially recorded in the encrypted data area 47 outside the area. Absolute address information indicating the recording positions of these content keys is recorded in the encrypted data analysis file 46 (see FIG. 4). In the example of FIG. 5, the encrypted data is recorded on the outermost periphery of the disc, but may be recorded in the lead-in area, lead-out area, program recording area, etc. of the disk.

  Next, the operation at the time of disc master creation of the disc master creation device 1 will be described with reference to the volume structure conversion processing flowchart shown in FIG. First, by reading the digital data material information recorded on the optical disc 2 by the dedicated device driver 7 provided in the formatter 3 of the disc master creating apparatus 1 shown in FIG. An information file 6 having various data necessary for creating a CD-ROM such as information relating to the key and flag information indicating the presence or absence of encryption is read out to the formatter 3.

  Next, the volume structure construction unit 8 of the formatter 3 constructs a volume structure of information to be recorded on the CD-ROM based on each information read by the dedicated device driver 7 and sets a layout, and generates management information. Management information for managing information in the CD-ROM is created based on the layout setting by the unit 8a.

  The volume structure construction unit 8 first analyzes the information file 6 read from the optical disc 2 (step S1), and whether or not content data encryption processing is necessary based on the analysis result, that is, each content file. It is determined whether or not to perform encryption and addition of an encryption processing file (step S2).

  If it is determined in the process of determination step S2 that the content data is not to be encrypted, the encryption process file is not added, the process proceeds to step S7, the information file 6 is deleted from the volume, and in step S8. The file management information is rewritten in accordance with these changes, and the volume structure conversion process is terminated.

  If it is determined in step S2 that the content data is to be encrypted, the content key information extraction unit 51 determines whether the content data to be encrypted is based on the information in the information file 6 in the volume 30 before conversion. Information about the encryption processing method is extracted. Then, the content key generation unit 53 performs a predetermined calculation using the information extracted by the content key extraction unit 51 to generate a content key. Then, a content key file group 45 is generated from the content key in the encryption processing file generation unit 54 and added to the converted volume 40 (step S3). For example, in this example, content keys 1, 2,..., N-1, n (n is a natural number) based on the information file 6 are recorded in the content key file group 45 (see FIG. 4). In this example, it is assumed that each content key is generated separately for each corresponding content file to be encrypted.

  In addition to the information file 6, the encrypted data information detection unit 52 calculates the address information of the end 33a of the content file group 33 from information such as the start position and data length of the file in the management information directory record. Then, the content key generation unit 53 performs a predetermined calculation process on the final address information to generate a content key. The content key is recorded as encrypted data in a predetermined area on the disk separately from the file system. In the encryption processing file generation unit 54, position information indicating the recording position on the disk is generated as the encryption data analysis file 46. Then, it is added to the volume 40 shown in FIG. 4 (steps S4 and S5).

  Similar to the file system, the encrypted data is converted into an EFM signal by an EFM signal generation circuit 9 described later, and then recorded in an encrypted data area 47 shown in FIG. For example, as shown in FIG. 5, content keys n + 1, n + 2,..., N + m−1, n + m (n and m are natural numbers) are recorded in the encrypted data, and their recording position information (physical addresses). ) Is recorded in the encryption data analysis file 46 on the file system. In this example, these m content keys n + 1,..., N + m are assumed to be necessary for decryption of all content files to be encrypted.

  Using the content key generated based on the information in the information file 6 and the content key generated based on the final address information uniquely calculated by the formatter 3, the encryption processing unit 55 encrypts the content file 33. The target content file is encrypted, and the content file group 33 is converted into the encrypted content file group 43 as shown in FIG. 4 (step S6).

  Thereafter, the volume structure construction unit 3 deletes the information file 6 from the volume (step S7). In accordance with these changes, the file management information 31 relating to file management in the management information is rewritten, changed to the file management information 41, and the volume structure conversion process is terminated (step S8).

  The file attributes of the original content data 5 provided from the optical disc 2 in the addition of the encryption processing file 44 including the content key file group 45 and the encryption data analysis file 46 and the deletion of the information file 6 performed in the above-described steps. The file system is analyzed so that the recording position is not affected.

  For example, when the encryption processing file 44 is added, the encryption processing file 44 is added to the end or empty area of the original content data, and the file system management information is changed. When deleting a file, the information file 6 is deleted from the original content data, and the file system management information is changed.

  As described above, when the encryption processing file 44 is recorded at the end or empty area of the original content data, even if the content file is encrypted with the content key, the file attribute of the content data intended by the content producer And can be recorded on the master disc 12 without changing the file storage order. As a result, information that does not depend on encryption is not lost from the original content data.

  As described above, after volume structure conversion processing is performed by the volume structure construction unit 8, the management information generated by the management information generation unit 8a, the content files of the content file group 43 that has been encrypted, and the content key file The group 45, the encrypted data analysis file 46, and the encrypted data are sequentially input from the volume structure construction unit 8 in FIG. 1 to the EFM signal generation circuit 9 at predetermined corresponding timings.

  Each data input to the EFM signal generation circuit 9 is blocked in units of a predetermined data amount, added with an error correction code, interleaved, and further added with an error correction code. The EFM signal generation circuit 9 outputs the processed data to the EFM signal output circuit 10 as a modulation signal EFM of a serial data string synchronized with the channel clock after interpolating the error correction code and EFM-modulating the error correction code. . At this time, the EFM signal generation circuit 9 also generates TOC (Table Of Contents) data and subcode data, processes the TOC data in the same manner, and appropriately converts the subcode data into TOC data. Interpolate.

  The modulation signal output from the EFM signal generation circuit 9 is NRZI (Non Return to Zero Inverter) modulation by the EFM signal output circuit 10 and is output to the cutting machine 4 as an output signal.

  The cutting machine 4 irradiates the disc master 12 with the laser beam while controlling on / off of the laser beam radiated to the disc master 12 by the laser driving circuit 11 by the modulation signal output from the EFM signal output circuit 10 of the formatter 3. The disk master 12 is rotationally driven under the condition of a constant linear velocity while sequentially changing the irradiation position of the laser beam from the inner periphery side to the outer periphery side of the disk master 12. As a result, the surface of the master disk 12 is sequentially exposed in accordance with the modulation signal, and a latent image serving as a CD-ROM pit row is formed on the exposure locus. Then, a master disk is created by developing the disk master 12, a stamper is created from the master disk, and a CD-ROM in which pit rows are formed by the stamper is sequentially created.

  In the encrypted data information detecting unit 52 shown in FIG. 4 of this example, the final address (logical address) is calculated from the sector size of the file system in order to obtain the final address information of the end 33a of the content file group 33. However, as another example, the final address information for encrypted data may be obtained based on the information converted to the EFM signal level. That is, the final address (physical address) can be calculated from the EFM bit pattern size after EFM modulation in the EFM signal generation circuit 9.

  In the former case, the recording position of the content key in the encrypted data recorded on the outermost periphery of the disk can be quickly read from the final address information of the file system. In the latter case, the final address information can be acquired as a value unique to the disk data.

  As described above, the disc master creating apparatus 1 of the present example records the provided content data on the disc master 12 separately from the content key created based on the information of the information file 6 provided from the authoring studio 20. In the process, the content key is uniquely generated by the formatter 3, and the content key that is uniquely generated is placed outside the lead-out area of the disc so that it is difficult to reproduce the content file simply by reading the management information by the operating system. It is recorded as encrypted data.

  As described above, in this example, in the process of converting the content data to the signal level recorded on the CD-ROM in the manufacture of the CD-ROM, a part of the content key is placed outside the predetermined area of the disc, for example, the lead-out area. Recorded as encrypted data on a track, and information related to the content key is recorded not only on the file system but also in another area such as outside the file system, which complicates the encryption method and CD-ROM playback not compatible with this system The device is further enhanced in security, for example, by simply reading the management information, the content key cannot be found easily.

  In addition, when comparing the case where illegal copying is prevented by inputting the conventional serial number and the case of this example, in this case, it is necessary to separately manage and distribute the data provided for the above input. Accordingly, the security of the CD-ROM can be improved by simple management.

  Further, according to the disc master creating apparatus 1 of this example, in addition to the normal content key generated based on the information provided from the information file 6, a unique content key is used in the process of recording the content data on the recording medium. When the content file is reproduced, both the content key derived from the authoring studio 20 and the content key uniquely generated by the formatter 3 are required, so that the security of the CD-ROM is improved. In particular, it is possible to prevent leakage of information related to CD-ROM encryption processing by a third party other than those related to the CD-ROM manufacturing factory, such as a content production related person of the authoring studio 20. Further, when the case of the formatter 3 is illegally disassembled, the recorded information format is analyzed by taking measures such as clearing program data recorded in a ROM (not shown) in the formatter 3 or the like. It can prevent more firmly.

  The process of adding and deleting directories and files is generally performed on an operating system (OS) equipped with a file system using a personal computer or the like, but once deployed on the OS. In the case of directories and files, there are cases where the OS-dependent attributes and the writing order, for example, the physical recording position on the disc, are changed when converted into the content data image again. In this case, in the authoring process for creating the content, it is impossible to reflect the intention such as data creation considering the efficiency at the time of reproduction by the content data creator. However, in this example, the management information of the file system is directly analyzed without developing the content data image on the OS, so that only the data file is added to the area that does not affect the original data. And deletion can be automatically performed by the formatter 3.

  Next, a process performed when the CD-ROM created as described above is reproduced by a CD-ROM reproduction apparatus will be described.

  FIG. 7 is a block diagram showing an example of an embodiment of a CD-ROM playback apparatus (information playback apparatus) according to the present invention. In the CD-ROM playback device 60 constituted by a computer or the like shown in FIG. 7, operation devices such as a keyboard, a mouse, and a monitor (not shown) are connected to a bus 67 via an interface (I / F) 61. Further, an optical disk drive 63 for reproducing a CD-ROM under the control of a central processing unit (CPU) 62 is connected to the bus 67.

  Further, the CD-ROM playback device 60 secures a work area in the random access memory (RAM) 65 according to the information recorded in the read only memory (ROM) 64, and executes the processing program recorded in the hard disk drive (HDD) 66. By being executed by the central processing unit 62, various processes are executed in accordance with instructions from the user. The central processing unit 62 is necessary for the processing of the encrypted content file and the encryption detection means for detecting whether or not the content data recorded on the CD-ROM is encrypted in response to an instruction from the user. It functions as a cryptographic analysis means for analyzing a cryptographic processing file and decrypting the encrypted content file.

  In the CD-ROM playback device 60 configured as described above, for example, when the user gives an instruction to install an application program recorded on the CD-ROM, the central processing unit 62 executes the processing procedure shown in FIG. The

  FIG. 8 is a flowchart showing application program installation processing by the CD-ROM playback device 60 shown in FIG. When the installation of the application program is instructed by the user, the central processing unit 62 determines whether or not the content file constituting the application program is encrypted based on the file management information related to the application program recorded on the CD-ROM. Is determined (step S11).

  For example, it can be determined that the content file has been encrypted by recording the content key file group 45 and the encrypted data analysis file 46 on the disc as shown in FIG. Alternatively, an identifier (flag) indicating recording of information necessary for processing such a file may be recorded in a system area (not shown) of a directory record of management information. When such an identifier is set, it is possible to quickly confirm that information necessary for file processing is set, so that information necessary for file processing can be quickly acquired during playback. .

  If it is determined that the content file is not encrypted in the process of the determination step S11 described above, the process proceeds to step S17, and the central processing unit 62 executes the setup program recorded on the CD-ROM, so that the conventional process is performed. Similarly, the normal installation process is executed. That is, the central processing unit 62 records each file recorded on the CD-ROM on the hard disk drive 66 and decompresses it, then creates an icon or the like on a display screen (not shown), and executes setup processing. This processing procedure ends.

  On the other hand, when it is determined that the content file has been encrypted in the process of determination step S11, the central processing unit 62 analyzes the file containing the content key. First, the content key file group 45 containing the content keys (1, 2,..., N) generated based on the information of the information file 6 provided from the authoring studio 20 is analyzed, and the content key is extracted ( Step S12).

  Next, the encryption data analysis file 46 is analyzed. In this encrypted data analysis file 46, the position information of the content keys n + 1,..., N + m recorded in the encrypted data area 47 of the disc is recorded. Is acquired (step S13). Then, the encrypted data is analyzed from the acquired position information (step S14), and the remaining content key necessary for processing the content file is extracted (step S15).

  By using all the content keys extracted as described above, the encrypted content file is decrypted. For example, in FIG. 4, the content key 1 of the content key file group 45 and the content keys n + 1,..., N + m of the encrypted data are decrypted, and the content key of the content key file group 45 is decrypted. 2 and the encrypted content key n + 1,..., N + m, the content file B ′ is decrypted. As described above, the content key created based on the information in the information file 6 and the content key created in the formatter 3 are both acquired and used simultaneously, so that the encrypted content file of the content file group 43 can be decrypted. Yes (step S16).

  Then, for example, by setting this content key as an argument and instructing the setup program recorded on the CD-ROM to execute, the file relating to the application program recorded on the CD-ROM is transferred to the hard disk drive 66. Then, the content is decompressed with the decrypted content key. Subsequently, the central processing unit 62 creates an icon or the like and executes a setup process (step S17), and ends the installation process procedure.

  In the example of FIG. 8, when the encrypted data analysis file 45 indicating the recording position information of the content key on the encrypted data does not exist, or when the content key position information is not recorded in the encrypted data analysis file 45 Alternatively, the position information may be searched from the lead-in.

  When a CD-ROM created from the disc master 12 on which a latent image is created by the information recording method of the present example configured as described above is installed in a computer that operates on a normal operating system, for example, a content key is included. Since the content of the encrypted data cannot be read, the content key cannot be acquired and the content file cannot be decrypted. For this reason, even if the file recorded on the CD-ROM is recorded on the hard disk drive in the CD-ROM playback device, it cannot function normally. Therefore, unauthorized use of the application program supplied by this CD-ROM can be prevented.

  Also, when copying this CD-ROM, the encrypted data cannot be copied even if it is transferred in file units and recorded on a writable CD-R or the like. Even if the copy can be made, simply reading the management information cannot find the content key in the encrypted data and cannot play the content file. This prevents unauthorized copying and prevents unauthorized use of the copy. It can be surely prevented.

  As described above, an unauthorized user who wants to reproduce an illegal copy of a CD-ROM on a CD-ROM playback apparatus that does not support the format according to the information recording method of this example can use the information on the CD-ROM. Can not. In this example, the authorized user is a person who intends to reproduce a disc of the format of this example sold on a legitimate route with a reproducing apparatus capable of reproducing the disc. An unauthorized user is a person who tries to play an illegally copied disc on a playback device that does not support the format of this example.

  According to the CD-ROM reproducing device 60 corresponding to the recording format according to the information recording method of this example, the content key file group 45 recorded on the CD-ROM and the recording position information of the content key recorded on the predetermined area of the disc are stored. The encrypted data file 46 can be reproduced and the content key can be detected from each. Each content file recorded on the hard disk 66 can be decompressed with these content keys.

  Thus, the CD-ROM playback device 60 can correctly install the application program recorded on the CD-ROM and execute the application program without inputting data such as a serial number.

  In the above-described embodiment, the case of creating a CD-ROM based on the ISO 9660 and UDF bridge standards has been described. However, the present invention is not limited to this, and each standard alone, HFS (Hierarchical File System), etc. The present invention can also be applied to other file system standards.

  For example, when the content data provided from the content data supply source is a file that is not an image of the file system of the information recording device, or when the CD-ROM file system must be recorded in the ISO9660 / UDF bridge format, When the content data supply source is an image of only ISO9660, etc., arithmetic processing or the like may be performed based on the entire sector size when converted to a file system image, that is, logical address information.

  For example, when content data having a file system image that meets the specifications of the CD-ROM is provided from a content supply source, the formatter 3 directly manages the file system without developing the content data image on the OS. Information can be analyzed and content data can be recorded faithfully according to the file system.

  Which of the above two methods is used may be selected by the formatter 3 based on the relationship between the file system of the provided content data and the file system to be recorded on the recording medium.

  In the above-described embodiment, the description has been made on the assumption that the original content information provided from the content data supply source is not changed, but the file attributes, the file storage order, etc. are changed intentionally, and the change is made. A method can be used in which the method is an encryption key different from the content key generated by the information file 6.

  In the above-described embodiment, the encrypted data analysis file 46 is generated as a file having the position information of the content key in the encrypted data. However, the encrypted data analysis file 46 is used as an encryption key of another file having the position information of the content key. For example, it is possible to use a technique for analyzing encrypted data in a plurality of stages.

  In the above-described embodiment, the content key on the encrypted data is simply extracted from only the position information of the encrypted data analysis file 46. However, a dedicated read mechanism is provided by changing the recording modulation method of the encrypted data. It is also possible to use a method of encryption by adding.

  In the above-described embodiment, the case of creating a CD-ROM has been described. However, the present invention is not limited to this, and further, a DVD (Digital Versatile Disk), a DVD next-generation disk, and a magneto-optical disk. It can be widely applied to various recording media such as memory cards and hard disks.

  In the above-described embodiment, an example in which the present invention is applied when providing an application program as content has been described. However, the present invention is not limited thereto, and for example, when providing music content, video content, or the like. Can also be widely applied.

  In addition, as an example of the embodiment, a disc master creating apparatus (information recording apparatus) and a CD-ROM reproducing apparatus (information reproducing apparatus) have been described. However, the present invention has an information recording function and an information reproducing function as an integrated configuration. Of course, the present invention can also be applied to an information recording / reproducing apparatus.

  Furthermore, the present invention is not limited to the above-described embodiments, and various other configurations can be taken without departing from the gist of the present invention.

It is a block diagram which shows the disc original disk production apparatus of the example of one embodiment of this invention. It is a figure which shows the example of the volume structure of CD-ROM. It is a figure where it uses for description of the outline | summary of volume structure conversion. It is a figure where it uses for description of volume structure conversion processing. It is a figure which shows the area structure example of CD-ROM. It is a flowchart of a volume structure conversion process. It is a block diagram of an example of a CD-ROM reproducing | regenerating apparatus. It is a flowchart which shows the installation process of an application program.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Disc master production device (information recording device), 2 ... Optical disc (content data supply source), 3 ... Formatter, 4 ... Cutting machine, 5 ... Content data, 6 ... Information file (content key generation information file), 7 DESCRIPTION OF SYMBOLS: Dedicated device driver, 8 ... Volume structure construction part, 8a ... Management information generation part, 9 ... EFM signal generation circuit, 10 ... EFM signal output circuit, 11 ... Laser drive circuit, 12 ... Disc original disc (recording medium), 20 ... Authoring studio, 30, 40 ... Volume structure, 31, 41 ... File management information, 33, 43 ... Content file, 33a ... End of file group, 45 ... Content key file group, 46 ... Encryption data analysis file, 47 ... Encryption data area, 51 ... Content key information extraction unit, 52 ... Encryption Data detection unit 53... Content key generation unit 54. Encryption file generation unit 55. Encryption processing unit 60. CD-ROM playback device (information playback device) 61. ... CPU, 63 ... optical disk drive, 64 ... ROM, 65 ... RAM, 66 ... HDD, 67 ... bus

Claims (5)

Converted from the volume structure indicating the area on the recording medium constructed to record the content file group and the content key generation information file having information related to the encryption processing of the content file group, and management after conversion Management information for generating management information in a volume structure indicating an area on a recording medium constructed to record information, a content file group, a file group including a first content key, and an encrypted data analysis file A generator,
A content key information extraction unit that extracts information related to the first content key of the content file to be encrypted from the content key generation information file;
An encrypted data information detection unit for detecting information related to the second content key obtained in the process of converting the content file group into a recording signal;
Based on the information about the first content key extracted by the content key information extraction unit and the information about the second content key detected by the encrypted data information detection unit A content key generation unit for generating the second content key;
An encryption processing unit that encrypts the content file to be encrypted using the first and second content keys;
Comprising a file containing the first content key, and a pre-Symbol encryption processing file generation unit which generates a file including the recording location information of the second content key,
Recording the management information, a content file group including the encrypted content file and a file group including the first content key on the recording medium, and recording the second content key in a user area of the recording medium An information recording device that records in an area that is not managed by management information for managing recorded data. The information recording apparatus according to claim 1, wherein the information related to the second content key is information indicating an end position of the content file group on the volume structure. The information recording apparatus according to claim 2, wherein a file including the first content key and a file including recording position information of the second content key are added to the end or empty area of the content file group of the volume structure. An information recording / reproducing apparatus comprising a recording device for recording a content file group on a recording medium and a reproducing device for reproducing the content file group recorded on the recording medium,
The recording device comprises:
Converted from the volume structure indicating the area on the recording medium constructed to record the content file group and the content key generation information file having information related to the encryption processing of the content file group, and management after conversion Management for generating management information in a volume structure indicating an area on a recording medium constructed to record information, a content file group, a file group including a first content key, and an encrypted data analysis file An information generator,
A content key information extraction unit that extracts information related to the first content key of the content file to be encrypted from the content key generation information file;
An encrypted data information detection unit for detecting information related to the second content key obtained in the process of converting the content file group into a recording signal;
Based on the information about the first content key extracted by the content key information extraction unit and the information about the second content key detected by the encrypted data information detection unit A content key generation unit for generating the second content key;
An encryption processing unit that encrypts the content file to be encrypted using the first and second content keys;
Comprising a file containing the first content key, and a pre-Symbol encryption processing file generation unit which generates a file including the recording location information of the second content key,
Recording the management information, a content file group including the encrypted content file and a file group including the first content key on the recording medium, and recording the second content key in a user area of the recording medium Recorded in an area not managed by the management information for managing the recorded data,
The playback device
Content file group, management information for managing the content file group, file group including the first content key of the content file to be encrypted, and information obtained in the process of converting the content file group into a recording signal Encryption detecting means for detecting that the content file group is encrypted for a recording medium recorded with at least a file including the recording position information of the second content key created based on
Analyzing the file including the first content key to obtain the first content key, analyzing the file including the recording position information of the second content key, and reading the recording position of the second content key; Cryptographic analysis means for obtaining the second content key recorded at the recording position,
An information recording / reproducing apparatus that uses the first content key and the second content key obtained by the encryption analysis unit to decrypt and reproduce the encryption target content file. Converted from the volume structure indicating the area on the recording medium constructed to record the content file group and the content key generation information file having information related to the encryption processing of the content file group, and management after conversion Generating the management information in the volume structure indicating the area on the recording medium constructed to record the information, the content file group, the file group including the first content key, and the encrypted data analysis file When,
Extracting information related to the first content key of the content file to be encrypted from the content key generation information file;
Detecting information on the second content key obtained in the process of converting the content file group into a recording signal;
Generating the first content key based on the extracted information about the first content key and the second content key based on the information about the detected second content key;
Encrypting the content file to be encrypted using the first and second content keys;
A file containing the first content key, and generating a file that contains the pre-type recording position information of the second content key,
Recording the management information, a content file group including the encrypted content file and a file group including the first content key on the recording medium, and recording the second content key in a user area of the recording medium An information recording method comprising: recording in a region not managed by management information for managing the recorded data.

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