JP4665974B2 - Information recording medium - Google Patents

Description

  The present invention relates to an information recording medium. More specifically, for example, an encryption key such as a copy protection key is recorded in an information recording medium for recording contents such as image data and music data in a form that is difficult to analyze, and efficient reproduction processing during reproduction is possible. It relates to the information recording medium.

  When data such as music data and image data is recorded as digital data on a recording medium, a recording process according to a predetermined recording format is performed. For example, an error detection / correction code is added to the original data to be recorded, and it is recorded after being converted (coded) into a format corresponding to a specific data recording / reproducing process.

  As an information recording system capable of recording high-density information, for example, a DVD (Digital Versatile Disc) system, or a Blu-Ray Disc system that performs information recording and reproduction using a blue laser that has been developed in recent years, etc. is there.

  By the way, contents stored in such an information recording medium include, for example, movies and music data. Many contents, such as music data and image data, generally have distribution rights or the like held by the creator or seller. Therefore, when distributing these contents, it is common to adopt a configuration that restricts the use of the contents, that is, permits the use of the contents only to authorized users and prevents unauthorized copying or the like. It is the target.

  A large-capacity recording medium such as a recording medium using a blue laser recording system capable of high-capacity recording can record data for one to several movies, for example, on one medium. Content can be recorded as digital information that does not deteriorate in copy and playback processing, and as a result, there are many problems of flooding of illegal copies. The problem of obstruction is growing. Under such circumstances, how to prevent illegal copying and protect the interests of copyright holders and distribution rights holders is an important issue.

  In order to prevent such unauthorized use of content, content stored in an information recording medium is recorded as encrypted content, and additional information such as copy protection key information as encryption key information applied to use of the encrypted content Alternatively, a configuration has been proposed in which information necessary for generating an encryption key or various control information such as content reproduction control and copy control is stored as secret information in an information recording medium. A configuration in which a playback processing program executed in a playback device of a user reads secret information such as a key corresponding to the content to be played, decrypts the content according to the read secret information, and executes use of the content according to the playback control information It is.

  For example, Patent Document 1 discloses a related art that discloses a configuration for embedding specific information such as an encryption key. Patent Document 1 discloses a configuration in which secret information is included in scrambled data.

Various technologies have been proposed for the storage processing configuration of additional information such as encryption key information, but on the other hand, its analysis technology has also evolved, and where secret information is stored in what manner on the information recording medium. There is a current situation that information such as whether information has been acquired is acquired by a user or an unauthorized content user, and leakage of additional information, falsification, and unauthorized copying of content have occurred. As a result, the usage form of the content based on the legitimate content usage right is lost, and there is a problem that the copyright and usage right of the content cannot be sufficiently protected.
JP 2002-93058 A

  The present invention has been made in view of the above-described problems. For example, an encryption key stored in a recording medium together with content, encryption key generation information, content reproduction control information, content copy control information, or other content attribute information. In addition, it is possible to record various additional information and encryption key data corresponding to these recorded data in a manner that cannot be read by general data reading processing, and also enables efficient reproduction processing at the time of data reproduction An object of the present invention is to provide an information recording medium.

The first aspect of the present invention is:
An information recording medium for recording encrypted data and encryption key data generated based on an encryption key applied to encryption processing of the encrypted data,
The encryption key data is recorded as scrambled data,
The scramble process is
A scramble process using a random number generated with a seed generated based on the error detection code itself corresponding to the encrypted data as input,
In the information reproducing apparatus for performing the reproducing process of the information recording medium, a seed is generated from the error detection code, and the encrypted data is decrypted by an encryption key that can be generated by a descrambling process using a random number based on the generated seed. An information recording medium is characterized in that it is configured to be performed.

  Furthermore, in one embodiment of the information recording medium of the present invention, the encryption key data is further recorded as data subjected to bit position conversion processing, and the bit position conversion processing is performed for error detection corresponding to the encrypted data. A bit position conversion process using a random number generated using a seed generated based on a code as an input, and generating a seed from the error detection code in an information reproducing apparatus that performs a reproduction process of the information recording medium. The encrypted data is decrypted with an encryption key that can be generated by a bit position conversion process using a random number based on the above.

  Furthermore, in an embodiment of the information recording medium of the present invention, the encryption key data is recorded as a physical recording signal different from the pit signal.

  Furthermore, in one embodiment of the information recording medium of the present invention, the encrypted data is additional information including copy protection information set in correspondence with the content, and the additional information is encrypted with an encryption key to be a pit. In addition to recording as a signal, the encryption key data is recorded as a physical recording signal different from the pit signal at the pit signal recording position.

  Furthermore, in one embodiment of the information recording medium of the present invention, the physical recording signal different from the pit signal based on the additional information and the pit signal based on the encryption key data is recorded in a lead-in area. It is characterized by.

  Other objects, features, and advantages of the present invention will become apparent from a more detailed description based on embodiments of the present invention described later and the accompanying drawings. In this specification, the system is a logical set configuration of a plurality of devices, and is not limited to one in which the devices of each configuration are in the same casing.

  According to the configuration of the present invention, in the configuration in which additional information such as copy protection information stored in the information recording medium is encrypted and recorded, and the encryption key is recorded together, the data processing for the encryption key data to be recorded Since the seed is generated based on the error correction code (EDC) corresponding to the additional information, the encryption key is recorded by executing the scramble process or the bit position conversion process using the random number generated based on the seed. Thus, it becomes possible to store the encryption key information on the disk with increased analysis difficulty.

  Furthermore, according to the configuration of the present invention, in the configuration in which additional information such as copy protection information stored in the information recording medium is encrypted and recorded, and the encryption key is recorded together, the additional information is a pit signal, Since the encryption key data is recorded as a physical recording signal different from the pit signal, for example, wobble data, both data are read in parallel, and the seed required for generating the encryption key based on the read data is acquired and acquired. A series of processing such as generation of an encryption key based on the seed and decryption of additional information based on the generated encryption key can be executed at high speed, and efficient data reproduction can be performed.

  Hereinafter, details of the information recording medium of the present invention, and related apparatuses and methods will be described with reference to the drawings.

  First, the configuration and processing of the configuration of the information recording processing apparatus of the present invention will be described with reference to FIG. The information recording processing apparatus described here includes a mastering apparatus as a master disk manufacturing apparatus called a so-called master disk, and further records information recording media such as DVDs or Blu-Ray disks that can be used by general users. This is an apparatus applicable as an apparatus including an information recording medium drive such as a reproduction apparatus or a PC. In other words, it includes not only a master disk but also an information processing apparatus that executes data recording processing on various information recording media that are writable (recordable) and rewritable (rewritable).

  With reference to FIG. 1, the configuration and processing of an information recording processing apparatus according to the present invention will be described. The information recording processing apparatus shown in FIG. 1 performs, with respect to a disc (information recording medium) 150, main data 101 including content information and additional information including, for example, copy protection information (CP Data), and encryption processing for the main data 101 An encryption key (copy protection key (CP Key)) 102 as a key is recorded.

  The content information and the additional information (copy protection information) included in the main data 101 are data encrypted based on the encryption key (copy protection key (CP Key)) 102 or an encryption key (copy protection key (CP Key)). )) Encrypted with the encryption key generated based on 102 and stored in the disk 150.

  The additional information included in the main data 101 includes copy protection information such as key information and reproduction control information applied to content encryption processing, and includes data including information that should be prevented from leakage. For example, EKB (Enabling Key Block) is stored as an encryption key block in which key information necessary for reproduction of encrypted content is encrypted and stored.

  The EKB is an encryption key data block that makes it possible to acquire an encryption key necessary for content decryption only by processing based on, for example, a device key stored in an information processing apparatus of a user having a valid license. This is a key that can be obtained only by a user device (information processing apparatus) having a valid content use license according to an information distribution method according to a so-called hierarchical tree structure, and an encryption key by a revoked user device. It is set as an encryption key block that can prevent acquisition of.

  The EKB is an example of data constituting the additional information, and the additional information in the present invention is not limited to the EKB, but is secret information such as other encryption key information, encryption key generation information, content reproduction control information, and license information. As long as the information is stored on the disk, the configuration data of the additional data is not limited.

  In FIG. 1, processing blocks 111 to 116 are processing blocks belonging to a main data processing sequence for executing main data processing, and blocks 121 to 125 are processing blocks belonging to an encryption key processing sequence for executing encryption key processing. It is. First, main data processing will be described.

  The main data 101, that is, the content information and the additional information are first encrypted with the encryption key (copy protection key) 102 in the encryption processing unit 111. The encrypted main data is divided into approximately 2 kbyte units (sectors) in the EDC encoding unit 112, and an error for checking whether there is an error in the recorded information with respect to the approximately 2 kbyte information. A detection code (EDC: Error Detection Code) is added.

  FIG. 2 shows a sector data structure to which EDC is added. One sector includes a 2048-byte data portion 161 and a 4-byte EDC (Error Detection Code) portion 162.

  The data to which EDC is added by the EDC encoding unit 112 shown in FIG. 1 is subjected to data scrambling processing for making the modulated signal pattern random in the scrambling processing unit 113. The scrambled information is set as an ECC block in which error correction information (ECC) for the scrambled data is encoded and address information is added in the ECC block generation unit 114.

  Next, the ECC block data to which the error correction information and the address information are added is added with the synchronization information in the main data modulation processing unit 115 and is used for the recording / reproducing band signal suitable for the recording / reproducing channel of the disc. Modulation processing is performed. Further, it is converted into an NRZI (Non Return to Zero Inverted) signal in which the polarity of the pulse is inverted according to the value of [0] or [1] of the modulation data, and this is converted to a LD (laser diode) driver 116 as a recording signal. Is output.

  The LD (laser diode) driver 116 modulates an LD (laser diode) 131 of the optical pickup (OP) 130 based on the NRZI signal, and the modulated laser light passes through the objective lens (obj lens) 133 to the disk. The encrypted data of the main data 101 that is collected on 150 and includes content information and additional information is recorded.

  Next, recording processing of the encryption key (copy protection key) 102 applied to encrypt the main data 101 composed of content information and additional information (copy protection information) will be described.

  In the encryption key (copy protection key) 102, the ECC block generation unit (CP ECC) 121 encodes error correction information (ECC) for the encryption key data, and an ECC block in which ECC is set in the encryption key data is generated. Next, the scramble processing unit (CP Scramble) 122 executes scramble processing.

  The scramble processing unit (CP Scramble) 122 applies a seed input from a seed generator 117 to generate a random number, and applies the generated random number to an ECC block generation unit (CP ECC) input. ) The scramble process of the encryption key data input from 121 is executed.

  The scrambled encryption key data is further input to the bit position conversion unit 123, and a bit position conversion process using a random number generated based on the seed input from the seed generator 117 is also performed. Executed.

  Details of each process of the seed generator 117, the scramble processing unit (CP Scramble) 122, and the bit position conversion unit 123 will be described with reference to FIG.

  3 shows an EDC encoding unit 112 belonging to the processing sequence of the main data shown in FIG. 1, an ECC block generation unit 121 belonging to the processing sequence of the encryption key 102, a scramble processing unit 122, a bit position conversion unit 123, and a seed A generation unit 117 is shown.

  The seed generation unit 117 receives EDC bit information set as an error detection code corresponding to the main data in the EDC encoding unit 112 belonging to the processing sequence of the main data, and performs encryption by performing arithmetic processing based on the EDC bit information. The seed information to be output to the ECC block generation unit 121 and the scramble processing unit 122 belonging to the processing sequence of the key 102 is generated.

  As described above with reference to FIG. 2, the EDC encoding unit 112 belonging to the processing sequence of the main data, for each content and additional information, has a 2048-byte data portion and a 4-byte EDC (Error Detection Code). ) Sector data constituted by the portion is generated.

  The seed generation unit 117 receives EDC as an error detection code set in the EDC encoding unit 112, and executes arithmetic processing based on the configuration bit information of the EDC to generate a seed.

As shown in FIG. 3, the arithmetic unit 161 configured in the seed generation unit 117 performs arithmetic processing with EDC as an input, and generates and outputs seed information of a predetermined number of bits. As a function for executing the calculation, for example, a calculation process on the extension field GF (2 ⁸ ) is applied.

  For example, the calculation unit 161 of the seed generation unit 117 generates n + m-bit seed information by calculation processing using EDC as an error detection code as an input, and a part (n bits) of the seed information is used as a seed A as an encryption key. The result is output to the scramble processing unit 122 belonging to the processing sequence, and the remaining m bits are output to the bit position conversion unit 123 as a seed B.

  Next, with reference to FIG. 4, the scramble process to which the seed information executed in the scramble processor 122 belonging to the process sequence of the encryption key 102 is applied will be described.

  The scramble processing unit 122 receives the encryption key data set as the ECC block from the ECC block generation unit 121 of the processing sequence of the encryption key 102 and, as described with reference to FIG. The seed information (seed A) generated based on the data error detection information (EDC) is input.

  As shown in FIG. 4, the scramble processing unit 122 inputs the seed A to the random number generator 171 configured in the scramble processing unit 122 and generates a random number based on the seed A. For example, the seed A value is set in the random number generator 171 as an initial value, and a random number is generated for each system clock. As the random number generator 171, for example, a configuration including a linear feedback shift register (LFSR) or a configuration including a pseudo random number generator can be applied.

  The random number generated by the random number generator 171 based on the seed A is subjected to exclusive OR operation in the encryption key data (copy protection key data) input from the ECC block generation unit 121 and the exclusive OR unit 172, and scrambled data Is generated. The generated scrambled data is input to the bit position conversion unit 123 which is the next processing stage of the encryption key processing sequence.

  The bit position conversion unit 123 performs a bit position conversion process using seed information (seed B) for the scrambled data of the encryption key data input from the scramble processing unit 122.

  With reference to FIG. 5, the bit position conversion process to which the seed information (seed B) executed in the bit position conversion unit 123 is applied will be described.

  The bit position conversion unit 123 inputs the seed B to the random number generator 181 in the bit position conversion unit 123 and generates a random number based on the seed B. For example, the seed B value is set as an initial value in the random number generator 181 and a random number is generated for each system clock. As the random number generator 181, similarly to the scramble processing unit 122, for example, a configuration constituted by a linear feedback shift register (LFSR) or a pseudo random number generator can be applied.

  On the other hand, the constituent bits of the encryption key data (copy protection key data) input from the scramble processing unit 122 are sequentially stored in the data storage area of the RAM 182. The random number generated by the random number generator 181 based on the seed B is input to the RAM 182 as read address data for the RAM 182.

  According to an address generated based on this random number, the constituent bits of the scrambled encryption key data (copy protection key data) stored in the RAM 182 are read out and serially output.

  For example, when the scramble data of the encryption key data (copy protection key data) input from the scramble processing unit 122 is 128-bit data, the first bit of the 128-bit scramble data input from the scramble process unit 122 has the RAM 182. Is stored in the memory location of address [001], the second bit is stored in the memory location of address [002], the third bit is the memory location of address [003], and so on up to the 128th bit. Stored in memory location.

  On the other hand, the random number generator 181 randomly outputs the address data 1 to 128 to the RAM 182 based on the seed B generated based on the error detection information (EDC) of the main data. For example, the random number generator 181 outputs addresses such as [125], [003], [084],.

  The RAM 182 applies the address input from the random number generator 181 as a data read address, first reads the bit information stored in the memory location [125], and then stores it in the memory location [003]. The read bit information is read, and then the bit information stored at the memory location [084] is read. These processes are executed, the positions of the constituent bits of the scrambled encryption key data stored in the RAM 182 are exchanged, and bit position conversion data is output.

  The bit position conversion data output from the bit position conversion unit 123 is input to the CP modulation processing unit 124 that is the next processing unit belonging to the encryption key processing sequence.

  Returning to FIG. 1, the description of the recording process of the encryption key 102 will be continued. The CP modulation processing unit 124 performs modulation processing on the encryption key data output from the bit position conversion unit 123, and performs recording / reproduction suitable for a physical recording signal different from the pit signal, for example, a wobble recording / reproduction channel of the disc. A modulation process for converting a band signal is executed. Details of the wobble signal will be described later.

  The data modulated in the CP modulation processing unit 124 is NRZI-converted and then output to an EO (Electro-Optic = electro-optic element) driver 125, and the EO (Electro-Optic = electro-optic) of the optical pickup 130 based on the NRZI data. The laser beam is polarized by the modulation processing of the element, and a physical recording signal different from the pit signal based on the encryption key 102 data, for example, a wobble signal is recorded on the disk 150.

  A wobble signal recording process will be described with reference to FIG. Main data composed of additional information including content information and copy protection information is recorded with the space by the pit 201 and the length of the mark.

  On the other hand, the encryption key 102 data such as a copy protection key is recorded by controlling wobble recording, that is, fluctuation of a pit sequence for recording main data.

  The wobble recording signal 221 shown in FIG. 6 (A) generates a shake (H → L) in which the pit series for recording the main data moves from the upper stage to the lower stage shown in the figure. This wobble recording signal 221 corresponds to the recording bit [1] of the encryption key data.

  In addition, the wobble recording signal 222 shown in FIG. 6B generates a shake (L → H) in which the pit series for recording the main data moves from the lower stage to the upper stage shown in the figure. The wobble recording signal 222 corresponds to the recording bit [0] of the encryption key data.

  Note that one bit in the wobble recording signal corresponds to the recording pit fluctuation state in the length of 68T (T is one channel length of the pit signal) of the main data recorded as the pit signal, as pit information. For every 68T of main data to be recorded, one constituent bit of the encryption key data is read.

  In this way, the main data composed of additional information including content information and copy protection information is recorded as pit information, and the encryption key is recorded as a wobble recording signal, thereby superimposing the main data and the encryption key. Thus, the data can be recorded on the disc, and the data (main data and encryption key) can be read in parallel when reading the data.

  In addition, although the structure which records an encryption key as a wobble (wobble) recording signal as an example was demonstrated here, if an encryption key is not a wobble (wobble) recording signal but a physical recording signal different from a pit signal, It is possible to adopt recording methods in various modes. For example, a recording method based on a change in pit width that can be recorded only on a ROM disk, a change in the pit shape itself, or a change in groove depth may be applied.

  The configuration of the disc generated by the recording process described above will be described with reference to FIG. As described above, the information recording processing apparatus shown in FIG. 1 includes a mastering apparatus as a master disk manufacturing apparatus called a so-called master disk, and further includes a DVD or a Blu-Ray disk that can be used by general users. It is an apparatus applicable as an apparatus including an information recording medium drive such as an information recording medium recording / reproducing apparatus or a PC. That is, it includes not only a master disk but also an information processing apparatus that performs data recording processing on various information recording media that are writable (recordable) and rewritable (rewritable). It is a figure which shows information recording media, such as a master disk produced | generated by the recording process of main data and encryption key data, or the DVD or Blu-Ray disk which can be produced | generated by the general user by the stamping process based on a master disk.

  The information recording medium 310 includes a data area 311 that stores content, a lead-in area 312 that stores additional information such as copy protection information and content reproduction control information, and a lead-out area 313 that is set at the outer periphery of the data area of the disc. Composed.

  The information in the lead-in area is an area that cannot be read in normal data reproduction processing, and specific processing steps such as a content encryption key acquisition step and a reproduction control information acquisition step executed in the execution of a specific content reproduction program Reading is possible only in.

  This lead-in area stores additional information including a content key as a content encryption key, data necessary for generating the content key, copy protection information such as reproduction control information, and the like. It is recorded as data encrypted by the encryption key 102 (see FIG. 1) described above. The recording data is recorded as pit data, while the encryption key is recorded as a wobble recording signal set corresponding to the recording pit of the additional data. That is, the additional data and the encryption key of the additional data are recorded on the disc in a superimposed manner.

  FIG. 8 shows an example of a recording signal in the lead-in area. (A) is additional information including copy protection information such as reproduction control information recorded as pit information. (B) is encryption key information composed of a wobble recording signal recorded by the swing of the recording pit of (A).

  The additional information including the pit information is data encrypted with an encryption key that can be acquired from a wobble recording signal.

  The information reproduction processing apparatus reads in parallel additional information composed of pit information recorded in a superimposed manner in the lead-in area and physical recording signal different from the pit signal, for example, encryption key data composed of a wobble recording signal. It is possible to obtain an encryption key based on the read wobble recording signal, decrypt the encrypted additional data obtained by reading the pit information based on the obtained encryption key, and get.

  Here, the example in which the additional data and the encryption key data are stored in the lead-in area has been described. However, the additional data and the encryption key data may be stored in the data area.

  Next, a data processing sequence of an encryption key based on a seed obtained by applying EDC of main data executed in the information recording processing apparatus of the present invention will be described with reference to FIG.

  In step S101, an error correction code (EDC) of main data is acquired. The main data is content or additional data, and is data recorded as pit information on the disc.

  In step S102, seeds (seed A and seed B) are generated based on the error correction code (EDC) of the acquired main data. This process is a process for generating a seed by executing an operation based on EDC in the seed generation unit 117 as described above with reference to FIG.

  Next, in step S103, a random number is generated based on the seed A, and the encryption key data is scrambled with the generated random number. This process is a process executed in the scramble processing unit 122 as described above with reference to FIG.

  Next, in step S104, a random number is generated based on the seed B, and bit position conversion of the encryption key data is executed using the generated random number. This process is a process executed in the bit position conversion unit 123 as described above with reference to FIG.

  Next, in step S105, a modulation process is performed on the encryption key data that has been subjected to the scramble process and the bit position conversion process, and then recorded on the disk as a wobble signal.

  Next, the processing and configuration of the information reproduction processing apparatus for reproducing the information recording medium (see FIG. 7) storing the above-described recording data will be described with reference to FIG.

  The information reproduction processing apparatus shown in FIG. 10 executes processing for reading content from the disc 500 and reading additional information composed of copy protection information and the like. Content and additional information are recorded as main data 501 by a pit signal, and are also recorded as encrypted data by an encryption key (copy protection key) 502. Therefore, a decryption process using the encryption key (copy protection key) 502 is required for the main data reproduction process.

  First, a reproduction sequence of main data 501 composed of additional information including content information stored in the disc 500 and copy protection information will be described.

  The main data is recorded as a pit signal on the disc 500 and is read from the disc 500 by the optical pickup 510. The read signal is demodulated in a modulation decoding unit (modulation DEC) 511.

  Next, an error correction processing unit (ECC) 512 executes error correction processing based on ECC and acquisition of address information. Next, descrambling section 513 performs descrambling processing, that is, descrambling processing is performed on information that has been scrambled so that the modulation signal is random during data recording, and descrambling is released.

  Further, the error detection unit (EDC) 514 verifies the presence / absence of a data error with respect to the descrambled information by using an error detection code (EDC) set in units of 2 kB sectors, and executes error correction. Thereafter, the decryption processing unit 515 performs decryption processing using the encryption key (copy protection key) 502 generated based on the data (wobble signal) read from the disc 500 to generate main data 501. Is output.

  Next, a process for reading and generating the encryption key (copy protection key) 502 from the disk 500 will be described. The encryption key (copy protection key) is read from the disc 500 by the optical pickup (OP) 510 as a push-pull signal as a physical recording signal different from the pit signal, for example, a wobble signal.

  The read wobble signal is demodulated in the CP modulation decoding unit (CP modulation DEC) 521. The demodulated signal is then subjected to bit position conversion processing in a bit position conversion unit 522.

  The bit position conversion unit 522 receives a seed generated based on the error detection code (EDC) of the main data from the seed information generation unit 517, generates a random number based on the seed, and generates a bit based on the generated random number. Perform position conversion.

  The seed information generation unit 517 has the same configuration as that of the seed generation unit 117 in the information recording / reproduction processing apparatus described above with reference to FIG. 1, and inputs an error detection code (EDC) of main data to perform arithmetic processing. And generate a seed (seed B) to be output to the bit position conversion unit 522 and a seed (seed A) to be output to the descrambling unit 523.

  The bit position conversion unit 522 receives the seed B from the seed information generation unit 517, applies a random number generated based on the seed B, and performs bit position conversion executed in the recording process described above with reference to FIG. An algorithm reverse to the process is executed to generate data having a bit position before the bit position conversion process.

  The data having the original bit position generated by the processing in the bit position conversion unit 522 is then input to the descrambling unit 523, and the descrambling process is executed.

  The descrambling unit 523 receives the seed A from the seed information generation unit 517, applies a random number generated based on the seed A, and reverses the scramble process in the recording process described above with reference to FIG. To cancel the scramble and generate data before the scramble process.

  Data descrambled by the descrambling unit 523 is input to a CP error correction processing unit (CP ECC) 524, and error correction processing based on ECC is performed to obtain an encryption key (copy protection key) 502.

  By applying the encryption key (copy protection key) 502 acquired by this process, the decryption processing unit 515 executes the decryption process of the main data including the additional data, and outputs the main data 501.

  For example, the encryption key of the additional data including the copy protection information is recorded as a wobble signal corresponding to the pit of the additional data including the copy protection information, and the pit signal reading and the wobble signal reading are performed in parallel. The processing for the main data executed in the blocks 511 to 515 shown in FIG. 10 and the processing for the encryption key executed in the blocks 521 to 524 are executed in parallel to improve the efficiency. Data can be read, decoded, and reproduced.

  Next, with reference to FIG. 11, an encryption key reading and generating process sequence from the disk will be described. In step S201, a wobble signal is read from the disk, and demodulation processing is executed. In step S202, an error correction code (EDC) of main data is acquired, and seeds (seed A and seed B) are generated based on the acquired error correction code (EDC) of main data. This process is the same process as described above with reference to FIG. 3, and the seed generation unit 517 performs a calculation based on EDC to generate a seed.

  Next, in step S203, a random number is generated based on the seed B, and bit position conversion of the encryption key data is executed using the generated random number. This process is a process of generating data having a bit position before the bit position conversion process by executing an algorithm reverse to the bit position conversion process executed in the data recording process described above with reference to FIG.

  Next, in step S204, a random number is generated based on the seed A, and the encryption key data is scrambled with the generated random number. This process is a process for generating data before the scramble process by executing an algorithm reverse to the scramble process executed in the data recording process described above with reference to FIG.

  In step S205, error correction processing based on ECC is performed, and an encryption key (copy protection key) is acquired. By applying this encryption key (copy protection key), the main data including the additional data is decrypted.

  Next, the configuration of an information recording / reproduction processing apparatus having, for example, a DVD drive or a Blu-Ray drive as a reproduction processing device for an information recording medium will be described with reference to FIG.

  The disc 600 is a disc, DVD, or Blu-Ray disc in which the above-described data, that is, encrypted main data is recorded as a pit signal and encryption key data is recorded as a wobble signal.

  The recording / reproducing signal input / output unit (OP) 611 includes an optical system including a laser diode, a reproducing amplifier, a biaxial actuator, and the like, and executes reading of signals on the disk 600. Note that the apparatus shown in FIG. 12 has an apparatus configuration capable of recording processing.

  A wobble signal processing circuit 612 acquires a wobble signal acquired from the disk 600, and executes demodulation processing of the read signal.

  The encryption key decoder (CP key DEC) 616 receives the timing signal from the recording / reproduction signal processing unit (RW circuit) 615 and also based on the error detection code (EDC) data of the main data input from the modulation / demodulation ECC processing circuit 617. Generate seeds (seed A, seed B), generate random numbers based on the generated seeds, execute bit position conversion and descrambling using the generated random numbers, execute error correction based on ECC, and perform encryption key (Copy protection key) is generated.

  A recording / reproducing signal processing unit (RW circuit) 615 performs recording compensation when data is recorded on the disc 600, and performs binarized data reproduction using a PLL or the like when reproducing data from the disc 600. The modulation / demodulation ECC processing circuit 617 executes modulation / demodulation processing of recording / reproduction data, performs error correction encoding, decoding, error correction processing, and further reproduces address information. The modulation / demodulation ECC processing circuit 617 extracts an error detection code (EDC) set in each sector data of the main data and outputs it to the encryption key decoder (CP key DEC) 616.

  The decryption processing unit 618 applies the encryption key (copy protection key) generated by the encryption key decoder (CP key DEC) 616 based on the wobble signal read from the disc 600 to encrypt the main data. For example, the decryption process of the encrypted copy protection information as the encrypted additional data and the decryption process of the encrypted content are executed, and the decryption result is output to the AV system 620 that executes the content reproduction process.

  The servo signal control circuit 613 performs servo control of the biaxial actuator and seek control of the optical pickup head. The spindle control circuit 614 controls a spindle motor that rotates the disk 600. A system control unit (Syscon) 619 communicates with the AV system 620 and controls each processing block.

  A process for acquiring an encryption key (copy protection key) recorded as a wobble signal on the disc 600 and reproducing main data, for example, copy protection information as additional information, will be described.

  First, the additional information reproduction command is sent from the AV system 620 to the system control unit 619. The system control unit 619 obtains address information from the modulation / demodulation circuit 617, causes the servo signal control circuit 613 to seek the pickup, and moves the optical pickup head so that data at a desired address position can be read.

  The read signal of the optical pickup head from the set position is output to the wobble signal processing circuit 612. The wobble signal processing circuit 612 demodulates the read wobble signal, and the demodulated signal is input to the encryption key decoder 616. .

  The encryption key decoder 616 obtains a timing signal from the recording / playback signal processing unit 615, and further inputs an error detection code (EDC) set in the additional information recorded as a pit signal from the modulation / demodulation ECC processing circuit 617, and EDC Bit information position rearrangement by random numbers based on seeds generated by applying data, descrambling, and error correction are performed to obtain an encryption key (copy protection key).

  On the other hand, additional information such as copy protection information that is superimposed and recorded with the encryption key (copy protection key) data is simultaneously reproduced by the recording / reproduction signal processing unit 615 by data processing using a PLL circuit. The reproduction data is demodulated in the modulation / demodulation ECC processing circuit 617, and the demodulated bit stream is subjected to error correction decoding based on the ECC.

  Further, decryption processing of the encrypted additional data using the encryption key generated by the encryption key decoder 616 based on the wobble signal is executed in the decryption processing unit 618, and the decryption result is output to the AV system 620.

  Since the encryption key data of the additional information is recorded as a wobble signal at the pit signal position (for example, the lead-in area) where the additional information as the main data is recorded, the encrypted additional data is not accessed separately. It is possible to execute reading and reading of the encryption key from the disk in parallel, and decryption of the encrypted main data with the generated encryption key by executing parallel processing such as demodulation and error correction of each read data Processing time until the processing is shortened, and efficient data reading and reproduction are possible.

  Next, the reproduction processing of the encrypted content stored on the disc 600 will be described.

  First, a content playback command is sent from the AV system 620 to the system control unit 619. The system control unit 619 acquires address information from the modulation / demodulation circuit 617, and causes the servo signal control circuit 613 to perform pickup seek according to the acquired address information, and moves the optical pickup to a desired address position.

  Further, a reproduction signal is obtained from the optical pickup, and reproduction data is obtained by a PLL or the like in the recording / reproduction signal processing unit 615. The reproduction data is subjected to demodulation processing and error correction processing in the modulation / demodulation ECC processing circuit 617.

  Next, in the decryption processing unit 618, decryption processing of the encrypted content read from the disc 600 is executed. An encryption key generated by the encryption key decoder 616 based on the wobble signal is applied to the decryption process.

  Content, for example, an image / audio reproduction bit stream, as a result of the decoding process in the decoding processing unit 618 is output to the AV system 620.

  The additional information stored in the information recording medium is data encrypted with an encryption key recorded as a wobble signal, and the content is also recorded as encrypted data. The content is encrypted with an encryption key recorded as a wobble signal or a content key generated based on the encryption key.

  Therefore, when the content is encrypted with the content key, the content key generation process using the encryption key recorded as the wobble signal is executed, and the decryption process of the encrypted content is performed based on the content key. Execute.

  The additional information may include information necessary for acquiring the above-described content key, for example, the above-described EKB. The additional information includes key data, key generation information, content reproduction control information, content copy control information, and other content attribute information applied to the decryption process of the encrypted content.

  The additional information is recorded as encrypted data, for example, as a pit signal in the lead-in area of the disc as described above, and the encryption key data as a key applied to the encryption of the additional information is the wobble at the position corresponding to the pit information. It is recorded as a (Wobble) signal.

  Therefore, when reproducing the additional information, it is possible to execute in parallel the reading of the encrypted additional information and the encryption key applied to the encryption from the disk, and perform the processes such as demodulation and error correction of each read data in parallel. This makes it possible to efficiently generate the encryption key and decrypt and reproduce the additional information based on the generated encryption key.

  The present invention has been described in detail above with reference to specific embodiments. However, it is obvious that those skilled in the art can make modifications and substitutions of the embodiments without departing from the gist of the present invention. In other words, the present invention has been disclosed in the form of exemplification, and should not be interpreted in a limited manner. In order to determine the gist of the present invention, the claims section described at the beginning should be considered.

  The series of processes described in the specification can be executed by hardware, software, or a combined configuration of both. When executing processing by software, the program recording the processing sequence is installed in a memory in a computer incorporated in dedicated hardware and executed, or the program is executed on a general-purpose computer capable of executing various processing. It can be installed and run.

  For example, the program can be recorded in advance on a hard disk or ROM (Read Only Memory) as a recording medium. Alternatively, the program is temporarily or permanently stored on a removable recording medium such as a flexible disk, a CD-ROM (Compact Disc Read Only Memory), an MO (Magneto optical) disk, a DVD (Digital Versatile Disc), a magnetic disk, or a semiconductor memory. It can be stored (recorded). Such a removable recording medium can be provided as so-called package software.

  The program is installed on the computer from the removable recording medium as described above, or is wirelessly transferred from the download site to the computer, or is wired to the computer via a network such as a LAN (Local Area Network) or the Internet. The computer can receive the program transferred in this manner and install it on a recording medium such as a built-in hard disk.

  Note that the various processes described in the specification are not only executed in time series according to the description, but may be executed in parallel or individually according to the processing capability of the apparatus that executes the processes or as necessary. Further, in this specification, the system is a logical set configuration of a plurality of devices, and the devices of each configuration are not limited to being in the same casing.

  As described above, according to the configuration of the present invention, additional information such as copy protection information stored in the information recording medium is encrypted and recorded, and the encryption key is recorded together. As a data process for encryption key data, a seed is generated based on an error correction code (EDC) corresponding to additional information, and a scramble process or a bit position conversion process to which a random number generated based on the seed is applied is performed to perform an encryption key Therefore, it is possible to store the encryption key information on the disk with improved analysis difficulty. Therefore, for example, content that requires copyright protection is stored in a recording medium, and it is difficult to analyze additional information such as key information, key generation information, content reproduction control information, and copy control information applied to the decryption processing of the content. The present invention can be applied to an information recording processing device, an information reproduction processing device, and an information recording medium in a configuration that needs to be embedded in various ways.

  Furthermore, according to the configuration of the present invention, in the configuration in which additional information such as copy protection information stored in the information recording medium is encrypted and recorded, and the encryption key is recorded together, the additional information is pit information, Since the encryption key data was recorded as wobble data, both data were read in parallel, the seed required for generating the encryption key based on the read data was obtained, and the encryption key was generated and generated based on the acquired seed A series of processing such as decryption of additional information based on the encryption key can be executed at high speed, and efficient data reproduction can be performed. Therefore, for example, content that requires copyright protection is stored in a recording medium, and it is difficult to analyze additional information such as key information, key generation information, content reproduction control information, and copy control information applied to the decryption processing of the content. The present invention can be applied to an information recording processing device, an information reproduction processing device, and an information recording medium in a configuration that needs to be embedded in various ways.

It is a figure which shows the structure of the information recording processing apparatus relevant to this invention. It is a figure which shows the structure of the sector data as recording data in the information recording processing apparatus relevant to this invention. It is a figure explaining the detail of the data process with respect to the seed production | generation and encryption key in the information recording process relevant to this invention. It is a figure explaining the detail of the scramble process which applied the generation | occurrence | production random number based on the seed performed as a data process with respect to an encryption key in the information recording process relevant to this invention. It is a figure explaining the detail of the bit position conversion process which applied the generation | occurrence | production random number based on the seed performed as a data process with respect to an encryption key in the information recording process relevant to this invention. It is a figure explaining the detail of the pit signal recording of the main data in the information recording process relevant to this invention, and the wobble signal recording of an encryption key. It is a figure explaining the detail of the storage data of an information recording medium. It is a figure explaining the detail of the pit signal recording of the additional data in the information recording process relevant to this invention, and the wobble signal recording of the encryption key of additional data. It is a flowchart explaining the data processing sequence with respect to the encryption key in the information recording process relevant to this invention. It is a figure which shows the structure of the information reproduction | regeneration processing apparatus relevant to this invention. It is a flowchart explaining the data processing sequence with respect to the encryption key in the information reproduction | regeneration processing relevant to this invention. It is a figure explaining the structure of an information recording / reproducing processing apparatus relevant to this invention, and a process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Main data 102 Encryption key 111 Cryptographic processing part 112 EDC encoding part 113 Scramble processing part 114 ECC block generation part 115 Main data modulation processing part 116 LD driver 117 Seed generation part 121 ECC block generation part 122 Scramble processing part 123 Bit position conversion Unit 124 CP modulation processing unit 125 EO driver 130 optical pickup 131 laser diode 132 electro-optic conversion element 133 objective lens 161 data unit 162 EDC unit 171 random number generator 172 exclusive OR unit 181 random number generator 182 RAM
221, 222 Wobble recording signal 310 Information recording medium 311 Data area 312 Lead-in area 313 Lead-out area 500 Disc 501 Main data 502 Encryption key 510 Optical pickup 511 Modulation decoding section 512 Error correction section 513 Descramble section 514 Error detection section 515 Decoding Processing unit 521 CP modulation decoding unit 522 Bit position conversion unit 523 Descramble unit 524 CP error correction processing unit 600 Disc 611 Recording / reproduction signal input / output unit 612 Wobble signal processing circuit 613 Servo signal control circuit 614 Spindle control circuit 615 Recording / reproduction signal processing Unit 616 encryption key decoder 617 modulation / demodulation ECC processing circuit 618 decryption processing unit 619 system control unit 620 AV system

Claims (4)

An information recording medium for recording encrypted data and encryption key data generated based on an encryption key applied to encryption processing of the encrypted data,
The encryption key data is recorded as scrambled data,
The scramble process is
A scramble process using a random number generated with a seed generated based on the error detection code itself corresponding to the encrypted data as input,
The information recording medium has a configuration in which the encrypted data is recorded as a pit signal, and the scrambled encryption key data is recorded as a wobble signal corresponding to a shake of the pit signal,
In an information reproducing apparatus that performs reproduction processing of the information recording medium, the pit signal and the wobble signal are read in parallel.
Scrambled encryption key data read from the wobble signal,
A seed is generated from the error detection code read from the pit signal, and the encrypted data read from the pit signal by an encryption key that can be generated by a descrambling process using a random number based on the generated seed. An information recording medium characterized by being configured to perform decoding. The encryption key data further includes:
Recorded as bit-position converted data,
The bit position conversion process includes:
A bit position conversion process applying a random number generated using a seed generated based on an error detection code corresponding to the encrypted data as an input;
In the information reproducing apparatus for reproducing the information recording medium, a seed is generated from the error detection code, and the encrypted data is decrypted by an encryption key that can be generated by a bit position conversion process using a random number based on the generated seed. The information recording medium according to claim 1, wherein the information recording medium is configured to perform the following. The encrypted data, the information recording medium according to claim 1, wherein the Dearuko additional information including copy protection information is set corresponding to the content. 2. The information recording medium according to claim 1 , wherein the pit signal based on the additional information and the wobble signal based on the encryption key data are recorded in a lead-in area.

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