JP4623367B2 - Signal processing circuit, content control apparatus, content control method, and content control program - Google Patents

Description

The present invention relates to a signal processing circuit , a content control apparatus , a content control method, and a content control program , and is suitable for application to, for example, a content reproduction apparatus that reproduces content data.

  2. Description of the Related Art In recent years, content reproducing apparatuses that acquire content data from a server of a content provider that provides content data such as audio data via the Internet and reproduce the content data have become widespread.

  In general, the content data provided by the content provider in this way indicates whether or not the content data has a right to use the content data for reasons such as protecting the interests of the copyright holder. Rights information is associated. Incidentally, the specific content of the right indicated in the right information includes, for example, the number of times the content data can be reproduced.

  When the content reproduction apparatus acquires the content data and the right information corresponding to the content data from the content provider's server, the right information is rewritten using a predetermined calculation method such as a one-way function from the right information. A right information inspection value used when inspecting whether or not (tampered) is calculated, and the calculated right information inspection value together with the acquired content data and right information is stored in a data storage medium (for example, the content reproduction device) (Hard disk drive)

  Incidentally, such a content reproduction apparatus calculates a right information inspection value from the right information by using a predetermined calculation method in accordance with a right processing module (software) stored in advance in an internal data storage medium. ing. Since this predetermined calculation method is concealed by the right processing module, the processing using this predetermined calculation method can be executed only by the content reproduction apparatus having this right processing module. In the following, for convenience of explanation, a right processing module implemented by software is referred to as a software right processing module.

  Thereafter, for example, when a playback operation for playing back the content data stored in the data storage medium is performed, the content playback device first responds to the content data according to the software right processing module stored in the data storage medium. A right information rewriting inspection process for inspecting whether the attached right information has not been rewritten is executed.

  That is, in the right information rewriting inspection process, the content reproduction apparatus performs a calculation using the predetermined calculation method for the right information associated with the content data. Then, the content reproduction apparatus compares the calculated value calculated by this calculation with the right information inspection value stored in the data storage medium, and as a result of this comparison, the calculated value and the right information inspection value match. If it is determined that the rights information has not been rewritten, it is determined that the rights information has been rewritten if the calculated value does not match the rights information inspection value. To do.

  If it is determined that the right information has been rewritten, the content reproduction apparatus does not execute the subsequent processing, and as a result, the content data is not reproduced. On the other hand, when it is determined that the rights information has not been rewritten, the content reproduction apparatus executes a right presence confirmation process for confirming whether or not there is a right to reproduce the content data based on the right information. If it is recognized as a result of this right presence / absence confirmation process that the right to reproduce the content data is recognized, a content reproduction process for reproducing the content data is executed.

  Thereby, according to this content reproduction apparatus, after acquiring the content data, rewriting (tampering) such as increasing the number of times the content data can be reproduced is performed on the right information associated with the content data. However, the content data can be controlled not to be reproduced, and thus unauthorized use of the content data can be prevented to some extent.

  However, this content reproduction apparatus has the following problems. In other words, in this case, the content reproduction apparatus properly obtains a large amount of content data from the server of the content provider. And what is stored in the data storage medium of this content reproduction device (a large number of acquired content data, right information corresponding to these content data, and a right information inspection value for inspecting this right information, etc.) A software right processing module for executing processing using a predetermined calculation method is directly copied to a data storage medium of another content playback apparatus.

  When such copying is performed skillfully, the same processing as that of the content reproduction apparatus that has legally acquired the content data is executed in the other content reproduction apparatus according to the copied software right processing module. As a result, the other content reproducing apparatus can reproduce such a large number of content data, and thus the profit of the copyright holder who authored the content data is harmed.

  As a technique for avoiding such a situation, a software right processing module in a content reproduction apparatus is realized by hardware such as an IC (Integrated Circuit) or a circuit board, and is used in the right information rewriting inspection process described above. It is conceivable that the information inspection value is stored not in the data storage medium storing the content data and the right information but in the right processing module realized by this hardware (see Patent Document 1). Hereinafter, for convenience of explanation, a right processing module implemented by hardware is referred to as a hardware right processing module.

  In a content playback device to which this method is applied, the content stored in the internal data storage medium (acquired content data and corresponding rights information) is illegally copied to another content playback device. Even if the work to be performed is performed, the right information inspection value stored in the hardware right processing module is not copied to the other content reproduction apparatus.

For this reason, in the other content reproduction device, even if a reproduction operation for reproducing the illegally copied content data is performed, the above-described right information rewriting inspection process is executed for the right information corresponding to the content data. Accordingly, the subsequent processing cannot be executed. Accordingly, it is possible to avoid reproducing the content data. Thus, when this method is employed, unauthorized use of content data can be further prevented than in the above-described content reproduction apparatus.
JP 2001-22271 A

  By the way, when realizing such a hardware right processing module, for example, a non-volatile memory for storing a right information inspection value is provided in the hardware right processing module.

  In this case, in order to prevent leakage of the right information inspection value stored in the nonvolatile memory to the outside, the nonvolatile memory is included in the hardware right processing module, etc. It is desirable not to be able to operate at all from the outside.

  However, in practice, the hardware rights processing module is configured without taking measures to include a general-purpose non-volatile memory that is widely distributed for reasons such as reducing the manufacturing cost of the hardware rights processing module. It is assumed that it is mounted on a circuit board.

  However, when the general-purpose nonvolatile memory is mounted on the circuit board constituting the hardware right processing module in this way, the nonvolatile memory is removed from the circuit board and stored in the nonvolatile memory. Since the right information inspection value can be copied to the non-volatile memory of another content playback apparatus, there arises a problem that unauthorized use of content data cannot be sufficiently prevented.

The present invention has been made in view of the above points, and intends to propose a signal processing circuit , a content control apparatus , a content control method, and a content control program that can prevent the illegal use of content data remarkably. is there.

In order to solve such a problem, the present invention checks the consistency between a hardware module that controls the use of content data based on the rights information of the content data and a device identifier that is transferred from the device on which the hardware module is mounted. to a first test value, provided with nonvolatile memory for storing a second check value to check the integrity of the rights information relating to content data, the hardware module, the content data and the by the instrument When the right information of the content data is acquired, the second inspection value is calculated from the right information, the calculated second inspection value is stored in the memory, and the first type firmware is loaded. time, the equipment identification in response to the first check value which is previously stored in the device identifier and the memory to be transferred from the device Check the integrity, in accordance with the check result, it checks the integrity of the rights information in accordance with the second check value in the right information and the memory of the content data, in accordance with the check result, right controlling the use of content data based on the information, when the second type of firmware is loaded, compares the group identifier in the group identifier and the second type of firmware in the device identifier transferred from equipment , in accordance with the comparison result, together with the re-storing the first check value for checking the integrity of the device identifier in the memory, from the rights information of the content data by calculating a second check value, the second was the operation The test value was memorized again in the memory.

The present invention therefore, the damage by illegal using a second type of firmware, Ru can be limited to a group identified by a group identifier in said second type of firmware.

According to the present invention, the hardware module that controls the use of the content data based on the rights information of the content data and the first check that checks the consistency of the device identifier transferred from the device on which the hardware module is mounted A non-volatile memory for storing a value and a second inspection value for checking the consistency of the right information related to the content data, and the hardware module uses the device to execute the content data and the right information of the content data. Is obtained from the right information, the second inspection value calculated is stored in the memory, and when the first type of firmware is loaded, The consistency of the device identifier is checked according to the device identifier to be transferred and the first inspection value stored in advance in the memory. According to the check result, the consistency of the right information is checked according to the right information of the content data and the second inspection value in the memory, and the content data is used based on the right information according to the check result. controlling, when the second type of firmware is loaded, it compares the group identifier in the group identifier and the second type of firmware in the device identifier transferred from the device, in accordance with the comparison result, The first inspection value for checking the consistency of the device identifier is stored again in the memory, the second inspection value is calculated from the right information of the content data, and the calculated second inspection value is stored in the memory. by the correct manner, the damage by illegal using a second type of firmware, identified by the group identifier in said second type of firmware Is can be limited to a group it is, thus unauthorized use of the content data can be reliably prevented as much.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

(1) Configuration of Content Reproduction Device In FIG. 1 and FIG. 2 conceptually showing FIG. 1, reference numeral 1 denotes a content reproduction device as a whole, and a device unique to the content reproduction device 1 that does not overlap with other content reproduction devices The identifier ID1 is stored in advance in a ROM (Read Only Memory) 2 that can read data and cannot write data. Thereby, it is possible to prevent the device identifier ID1 unique to the content reproduction apparatus 1 from being rewritten by an external operation. Incidentally, in the case of the present embodiment, for example, a serial number uniquely assigned to the content reproduction apparatus 1 is applied as the device identifier ID1.

  The hardware right processing module 3 provided in the content reproduction apparatus 1 executes, for example, a calculation using a first calculation method formed of a one-way function with respect to the device identifier ID1 stored in the ROM 2. The device identifier inspection value VM is calculated, and the calculated device identifier inspection value VM is stored in advance in the nonvolatile memory 4 connected to the hardware right processing module 3.

  Thus, in the case of the present embodiment, a one-way function is applied as the first calculation method used when calculating the device identifier inspection value VM from the device identifier ID1. This one-way function is a function in which it is easy to calculate a result from an argument, but it is difficult to obtain an argument from the calculated result. Thereby, it can be avoided that the device identifier ID1 is obtained from the device identifier inspection value VM calculated by the first calculation method.

  In the case of the present embodiment, for example, the hardware right processing module 3 includes a storage device (register or the like) that stores the first calculation method used when calculating the device identifier inspection value VM from the device identifier ID1. Thus, the first calculation method is concealed in the hardware right processing module 3. As a result, even if the third party refers to the device identifier ID1 stored in the ROM 2, the device identifier test value VM is calculated based on the referenced device identifier ID1. It can be avoided.

  When a content acquisition operation for acquiring content data (for example, audio data) D from the server SV of the content data provider is performed on the operation unit 5 of such a content playback device 1, content playback is performed accordingly. A CPU (Central Processing Unit) 6 that controls the entire apparatus 1 sends a content data request signal for requesting to provide the content data D according to the content acquisition operation via the input / output interface unit 7 and the Internet NT sequentially. , To the server SV of the content data provider.

  When this content data provider server SV receives the content data request signal from the content reproduction apparatus 1, for example, a billing process for charging the user of the content reproduction apparatus 1 for the provision of the content data D The content data D corresponding to the content data request signal and the right information INF indicating that there is a right to use the content data D are transmitted to the content reproduction apparatus 1 via the Internet NT. To send. In this case, the right information INF indicates the number of times that the content data D can be reproduced, for example.

  As a result, the CPU 6 of the content reproduction apparatus 1 receives the content data D transmitted from the server SV and the right information INF corresponding to the content data D via the input / output interface unit 7 and receives the data storage medium 8 (for example, a hard disk drive). ). In this way, the content reproduction apparatus 1 can legitimately acquire the content data D corresponding to the user content acquisition operation from the server SV of the content data provider.

  In addition, when the content data D is properly acquired in this way, the hardware right processing module 3 provided in the content reproduction device 1 controls the right information INF corresponding to the acquired content data D under the control of the CPU 6. For example, a calculation using the second calculation method composed of a one-way function is executed, thereby calculating a right information inspection value VR used for checking whether or not the right information INF has been rewritten. The right information inspection value VR is stored in the nonvolatile memory 4 in which the device identifier inspection value VM is stored.

  Thus, in the case of the present embodiment, a one-way function is applied as the second calculation method used when calculating the right information inspection value VR from the right information INF. Thereby, it can be avoided that the right information INF is obtained from the right information inspection value VR calculated by the second calculation method.

  In the case of the present embodiment, for example, the hardware right processing module 3 includes a storage device (register or the like) that stores the second calculation method used when calculating the right information inspection value VR from the right information INF. Thus, the second calculation method is concealed in the hardware right processing module 3. As a result, even if the right information INF stored in the data storage medium 8 is referred to by a third party, the value of the right information inspection value VR is calculated based on the referenced right information INF. Can be avoided.

Further, in the case of this embodiment, the device identifier check value VM and the right information check value VR which is adapted not calculated by a third party, for example, the content reproduction apparatus data arrangement in which only manufacturing side can know that manufactured the 1 (data The data is stored in the non-volatile memory 4 according to the format. Thus, it is very difficult for a third party to specify where the device identifier inspection value VM and the right information inspection value VR are stored in the storage area of the nonvolatile memory 4. Thus, out of the device identifier inspection value VM and the right information inspection value VR stored in the nonvolatile memory 4, for example, only the right information inspection value VR is read separately from the device identifier inspection value VM and read out. Copying to the non-volatile memory of the playback device can be prevented.

  Thereafter, the hardware right processing module 3 of the content reproduction apparatus 1 checks the right information stored in the non-volatile memory 4 every time the power is turned on in response to a user power-on operation, for example, under the control of the CPU 6. A right information validity check process for determining whether or not the value VR is valid calculated by the content reproduction apparatus 1 is executed.

  That is, in this right information validity checking process, the hardware right processing module 3 of the content reproduction apparatus 1 performs a calculation using the first calculation method for the device identifier ID1 stored in the ROM 2 of the content reproduction apparatus 1. Execute.

  Subsequently, the hardware right processing module 3 compares the value calculated by this calculation (hereinafter referred to as the first calculated value) with the device identifier test value VM stored in the nonvolatile memory 4. If it is recognized as a result of this comparison that the first calculated value matches the device identifier test value VM, the device identifier ID1 stored in the ROM 2 matches the device identifier test value VM. As a result, the right information inspection value VR stored so as not to be read separately from the device identifier inspection value VM is validated when the content reproduction apparatus 1 obtains the content data D. It is determined that

  On the other hand, when the hardware right processing module 3 recognizes that the first calculated value and the device identifier inspection value VM do not match as a result of the comparison, the device identifier ID1 stored in the ROM 2 and the device It is determined that the consistency with the identifier check value VM is not obtained, and as a result, the right information check value VR stored so as not to be read out separately from the device identifier check value VM is used as another content reproduction device, for example. It is determined that the copy was illegal.

  If it is determined that the right information inspection value VR is invalid, the hardware right processing module 3 uses the right information inspection value VR to inspect whether the right information INF has been rewritten. And the subsequent processing is not executed. Thus, in this case, the content reproduction process for reproducing the content data D corresponding to the right information INF is not executed.

  On the other hand, when it is determined that the right information inspection value VR is valid, the hardware right processing module 3 performs a reproduction operation for reproducing the content data D by the user via the operation unit 5. A right information rewriting inspection process for inspecting whether the right information INF corresponding to the content data D has been rewritten using the right information inspection value VR is executed.

  That is, in the right information rewriting inspection process, the hardware right processing module 3 executes a calculation using the second calculation method for the right information INF corresponding to the content data D.

  Subsequently, the hardware right processing module 3 determines the value calculated by this calculation (hereinafter referred to as the second calculated value) and the right information determined to be valid in the right information validity checking process described above. When the inspection value VR is compared, and it is recognized that the second calculated value and the right information inspection value VR do not match as a result of the comparison, the right information INF and the right information inspection value VR are consistent. It is determined that the right information INF has been rewritten.

  On the other hand, when the hardware right processing module 3 recognizes that the second calculated value and the right information inspection value VR coincide with each other as a result of the comparison, the hardware right processing module 3 calculates the right information INF and the right information inspection value VR. It is determined that consistency is obtained, and as a result, it is determined that the right information INF has not been rewritten.

  If it is determined that the rights information INF has not been rewritten, the hardware rights processing module 3 confirms whether or not there is a right to reproduce the content data D based on the rights information INF. Execute the process.

  That is, in this right presence / absence confirmation processing, when the hardware right processing module 3 recognizes that the right information INF indicates that the content data D can be reproduced, for example, one or more times, the content data D is stored. If it is determined that there is a right that can be reproduced, and the right information INF recognizes that the content data D can be reproduced, for example, 0 times, the content data D can be reproduced. Judge that there is no right.

  When it is determined that there is no right to reproduce the content data D, the hardware right processing module 3 does not execute the content reproduction process for reproducing the content data D.

  On the other hand, when it is determined that there is a right to reproduce the content data D, the hardware right processing module 3 reproduces the content such as, for example, decompressing and decoding the compression / encryption applied to the content data D. The processing is executed, and the audio signal obtained as a result is sent to the audio processing unit 9. As a result, the sound processing unit 9 outputs sound based on the sound signal from the hardware right processing module 3 through the speaker 10 under the control of the CPU 6.

  Next, the processing procedure RT1 of the hardware right processing module 3 provided in the content reproduction apparatus 1 will be described in detail using the flowchart shown in FIG.

  Incidentally, the processing procedure RT1 of the hardware right processing module 3 is valid if the right information inspection value VR stored in the nonvolatile memory 4 of the content reproduction apparatus 1 is not illegally copied from another content reproduction apparatus. It is determined that the right information inspection value VR is valid by the right information validity check processing procedure RT1a (steps SP1 to SP3) for checking whether or not the right information is correct and the right information validity check processing procedure RT1a. In this case, the rights information rewriting inspection processing procedure RT1b (steps SP4 to SP6) for inspecting whether or not the rights information INF has been rewritten using the rights information inspection value VR and the rights information rewriting inspection processing procedure RT1b. If it is determined that the information INF has not been rewritten, the content INF When the right existence confirmation processing procedure RT1c (steps SP7 to SP8) for confirming whether or not there is the right to reproduce the data D and the right existence confirmation processing procedure RT1c confirms that the right to reproduce the content data D is confirmed. And a content reproduction processing procedure RT1d (steps SP9 to SP11) for reproducing the content data D. These will be described in detail below.

  In step SP1, for example, when the content reproduction apparatus 1 is activated by performing a power-on operation to turn on the content reproduction apparatus 1, the device identifier ID1 read from the ROM 2 by the CPU 6 is the hardware right processing module. 3 is input.

  In response to this, the hardware right processing module 3 executes a calculation using the first calculation method for the input device identifier ID1 in step SP2, and the first calculated value calculated as a result of the calculation is obtained. And the device identifier inspection value VM stored in the nonvolatile memory 4 are compared.

  Then, the hardware right processing module 3 proceeds to step SP3, receives the result of the comparison in step SP2, and determines whether or not the input device identifier ID1 and the device identifier inspection value VM are consistent.

  If a positive result is obtained in step SP3, this means that the device identifier ID1 and the device identifier inspection value VM are consistent, and at this time, the hardware right processing module of the content reproduction device 1 3 is a legitimate value calculated when the content reproduction apparatus 1 obtains the content data D, and stores the rights information inspection value VR stored so as not to be read out separately from the device identifier inspection value VM. As a result, the process proceeds to step SP4.

  On the other hand, if a negative result is obtained in step SP3, this means that the device identifier ID1 and the device identifier inspection value VM are not consistent, and at this time, the hardware of the content reproduction device 1 The rights processing module 3 determines that the rights information inspection value VR stored so as not to be read out separately from the device identifier inspection value VM is, for example, illegally copied from another content reproduction device, and The process proceeds to result ending step SP12 and the processing procedure RT1 is ended.

  In step SP4, when a reproduction operation for reproducing the content data D is performed by the user via the operation unit 5, the right information INF corresponding to the content data D is read from the data storage medium 8 by the CPU 6, and hardware Input to the right processing module 3.

  In response to this, in step SP5, the hardware right processing module 3 executes a calculation using the second calculation method for the input right information INF, and the second calculated value calculated as a result of this calculation The right information inspection value VR determined as right in the right information validity inspection processing RT1a is compared.

  Then, the hardware right processing module 3 proceeds to step SP6, receives the result of the comparison in step SP5, and determines whether or not the input right information INF and the right information check value VR are consistent.

  If a positive result is obtained in step SP6, this means that the right information INF and the right information inspection value VR are consistent, and at this time, the hardware right processing module of the content reproduction apparatus 1 3 determines that this right information INF has not been rewritten and, as a result, proceeds to step SP7.

  On the other hand, if a negative result is obtained in step SP6, this means that the right information INF and the right information inspection value VR are not consistent with each other. At this time, the hardware of the content reproduction apparatus 1 The right processing module 3 determines that the right information INF has been rewritten, and as a result, without returning the content data D corresponding to the right information INF, for example, the process returns to the above-described step SP4 and a new reproduction by the user. Wait for the operation to take place.

  In step SP7, the hardware right processing module 3 checks whether or not there is a right to reproduce the content data D based on the right information INF determined not to be rewritten by the right information rewriting inspection process RT1b.

  Then, the hardware right processing module 3 proceeds to step SP8, receives the result of confirmation in step SP7, and determines whether or not there is a right to reproduce the content data D.

  If an affirmative result is obtained in this step SP8, for example, this means that one or more times are indicated as the number of times the content data D can be reproduced in this right information INF. The processing module 3 determines that there is a right to reproduce the content data D, and proceeds to the next step SP9.

  On the other hand, if a negative result is obtained in step SP8, for example, this means that 0 is indicated as the number of times the content data D can be reproduced in the right information INF. The hardware right processing module 3 determines that there is no right to reproduce the content data D, and as a result, returns to the above-described step SP4 without reproducing the content data D, and a new reproduction operation is performed by the user. I will wait for you.

  In step SP9, the content data D determined to have the right to be reproduced by the right presence / absence confirmation processing RT1c is read from the data storage medium 8 by the CPU 6 and input to the hardware right processing module 3.

  In response to this, the hardware right processing module 3 performs decompression decoding processing on the input content data D in step SP10.

  In step SP11, the hardware right processing module 3 outputs the audio signal obtained as a result of the decompression decoding process in step SP10 to the audio processing unit 9. Thus, the sound processing unit 9 emits sound based on this sound signal through the speaker 10 under the control of the CPU 6.

  As described above, the content playback apparatus 1 shown in FIGS. 1 and 2 includes the ROM 2 that stores the device identifier ID1 for identifying the content playback apparatus 1 so that the content playback apparatus 1 cannot be rewritten.

  Thus, for example, as shown in FIG. 4, the device identifier ID1a stored in the ROM 2A of a certain first content playback device 1A is changed to the device identifier ID1b stored in the ROM 2B of a certain second content playback device 1B. It is possible to prevent rewriting.

  1 and FIG. 2 is a data storage medium that stores content data D acquired from the server SV and right information INF indicating whether or not there is a right to reproduce the content data D. 8 has.

  Further, the content reproduction apparatus 1 shown in FIGS. 1 and 2 includes a right information inspection value VR for inspecting whether or not the right information INF corresponding to the acquired content data D has been rewritten, and the content reproduction apparatus. The non-volatile memory 4 stores the device identifier inspection value VM corresponding to the device identifier ID1 stored in the ROM 2 so as not to be read out separately.

  Accordingly, for example, as shown in FIG. 5, the content data Db legitimately acquired by the second content reproduction apparatus 1B, the right information INFb of the content data Db, and the right information for inspecting the right information INFb When the inspection value VRb is to be copied from the second content reproduction device 1B to the first content reproduction device 1A, the device identifier inspection value VMb stored in the nonvolatile memory 4B together with the right information inspection value VRb is also obtained. The second content reproduction device 1B is copied to the first content reproduction device 1A.

  Further, the hardware right processing module 3 of the content playback apparatus 1 shown in FIGS. 1 and 2 stores the device identifier inspection value VM stored in the nonvolatile memory 4 in the ROM 2 of the content playback apparatus 1. It is determined whether or not it corresponds to the device identifier ID1, and if the device identifier ID1 and the device identifier inspection value VM correspond to each other as a result of the determination, the device identifier ID1 is not read out separately from the device identifier inspection value VM. The right information rewriting inspection process RT1b for inspecting whether the right information INF has been rewritten using the right information inspection value VR stored in FIG. On the other hand, if the device identifier ID1 and the device identifier inspection value VM do not correspond as a result of the determination, the hardware right processing module 3 stores the hardware right processing module 3 so as not to be read out separately from the device identifier inspection value VM. The right information rewriting inspection process RT1b for inspecting whether the right information INF has been rewritten using the right information inspection value VR that has been set is not executed.

  Thus, in the case shown in FIG. 5, the device identifier inspection value VMb copied from the nonvolatile memory 4B of the second content playback device 1B to the nonvolatile memory 4A of the first content playback device 1A is Since it does not correspond to the device identifier ID1a stored in the ROM 2A of the one content playback device 1A, the first content playback device 1A does not separate from the device identifier test value VMb and copies the right information test value VRb. The right information rewriting inspection process RT1b is not executed using. As a result, the first content reproduction apparatus 1A does not execute the right presence / absence confirmation process RT1c and the content reproduction process RT1d after the right information rewriting inspection process RT1b, so that the second content reproduction apparatus 1B to the first content reproduction apparatus It is possible to avoid reproducing the content data Db illegally copied to 1A.

  In this way, according to the content reproduction apparatus 1 shown in FIGS. 1 and 2, unauthorized use of the content data D can be remarkably prevented.

  In the case of this embodiment, the hardware right processing module 3 includes a DSP (Digital Signal Processor), a memory, a register, etc., which are configured to execute various processes according to the firmware read from the data storage medium 8 on the circuit board. Connected and configured. The nonvolatile memory 4 connected to the hardware right processing module 3 may be mounted on a circuit board constituting the hardware right processing module 3 or may be provided outside the circuit board. .

  The first calculation method and the second calculation method described above include checksum, CRC (Cyclic Redundancy Check), hash function such as MD5 (Message Digest 5) and SHA1 (Secure Hash Algorithm 1), and a specific key. The used HMAC (Keyed Hashing for Message Authentication Code) -MD5, HMAC-SHA1, RSA, ECDSA (Elliptic Curve Digital Signature Algorithm), or the like can be applied.

(2) Fraud Prevention Using Special Firmware Here, consider a case where the hardware right processing module 3 and the nonvolatile memory 4 of the content reproduction apparatus 1 described above have failed. In this case, it is necessary to replace the hardware right processing module 3 and the non-volatile memory 4 with ones that operate normally, for example, by a repairer who repairs the content reproduction apparatus 1.

  However, the non-volatile memory 4 newly replaced in this way does not store the device identifier inspection value VM or the right information inspection value VR as shown in FIG. Thus, the content reproduction apparatus 1 that has been exchanged as described above cannot execute the above-described rights information validity inspection process RT1a and rights information rewriting inspection process RT1b, and as a result, the content data that has been obtained so far D cannot be played back.

  For this reason, when such replacement is performed, special firmware is loaded into the hardware right processing module 3 of the content reproduction apparatus 1 by, for example, a repairer. Thereby, the hardware right processing module 3 executes the test value generation / storage processing procedure RT2 as shown in FIG. 6 in accordance with the loaded special firmware.

  Here, the test value generation / storage processing procedure RT2 will be described with reference to FIG. In step SP21, the hardware right processing module 3 requests the CPU 6 to read the device identifier ID1 stored in the ROM 2 of the content reproduction apparatus 1. In response to this, the CPU 6 reads the device identifier ID1 from the ROM 2 and inputs it to the hardware right processing module 3.

  When the device identifier ID1 is input in this way, the hardware right processing module 3 proceeds to step SP22, executes a calculation using the first calculation method for the input device identifier ID1, and performs this calculation. The device identifier test value VM obtained as a result of is stored in the replaced nonvolatile memory 4.

  In subsequent step SP23, the hardware right processing module 3 requests the CPU 6 to read the right information INF stored in the data storage medium 8 of the content reproduction apparatus 1. In response to this, the CPU 6 reads the right information INF from the data storage medium 8 and inputs it to the hardware right processing module 3.

  When the right information INF is input in this way, the hardware right processing module 3 proceeds to step SP24, and executes a calculation using the second calculation method for the input right information INF. The right information inspection value VR obtained as a result of the above is stored in the replaced nonvolatile memory 4.

  In this way, in this inspection value generation and storage processing procedure RT2, the right to inspect the device identifier inspection value VM corresponding to the device identifier ID1 stored in the ROM 2 and the right information INF stored in the data storage medium 8. An information inspection value VR is newly generated, and the generated device identifier inspection value VM and right information inspection value VR are stored in the exchanged nonvolatile memory 4.

  As a result, the content reproduction apparatus 1 can again execute the above-described right information validity inspection process RT1a and right information rewrite inspection process RT1b, and as a result, reproduces the content data D that has been obtained so far. Will be able to.

  However, if the special firmware for executing the inspection value generation / storage process RT2 leaks to a third party other than the manufacturer or repairer who manufactures the content reproduction apparatus 1, as shown in FIG. There is a possibility of fraud.

  That is, as shown in FIG. 7A, first, content data Db and right information INFb legitimately acquired by the second content reproduction device 1B are obtained from the data storage medium 8B of the second content reproduction device 1B. It is illegally copied to the data storage medium 8A of the first content reproduction apparatus 1A. Next, special firmware for causing the hardware right processing module 3 of the first content reproduction apparatus 1A to execute the test value generation / storage processing procedure RT2 is loaded illegally. As a result, as shown in FIG. 7B, the non-volatile memory 4A of the first content reproduction device 1A has a device identifier corresponding to the device identifier ID1a stored in the ROM 2A of the first content reproduction device 1A. The inspection value VMa and the right information inspection value VRb for inspecting the right information INFb of the content data Db illegally copied from the second content reproduction apparatus 1B are generated and stored. In this case, the first content reproduction apparatus 1A can reproduce the content data Db illegally copied from the second content reproduction apparatus 1B.

  Further, since the fraud described with reference to FIG. 7 is possible in all the content reproduction apparatuses 1 that are already in widespread use, the profit of the copyright holder who has authored the content data D is significantly impaired.

  Actually, the content reproduction apparatus 1 in the present embodiment is configured to be able to suppress such damage caused by fraud. Hereinafter, this point will be described in detail with reference to FIG. 1 and FIG. 8 conceptually showing FIG.

  The content playback apparatus 1 stores, for example, an organization identifier for identifying the manufacturing company that manufactured the content playback apparatus 1 in the ROM 2 that stores the device identifier ID1 for identifying the content playback apparatus 1 so that it cannot be rewritten. ID2 is stored. Incidentally, in the case of the present embodiment, this organization identifier ID2 is assigned so as to be unique to each of a plurality of manufacturing companies that manufacture the content reproduction apparatus 1.

  In the case of the present embodiment, the organization identifier ID2 is stored in the ROM 2 so as to be included in the device identifier ID1. That is, for example, as shown in FIG. 9, an organization identifier ID2 for identifying the manufacturing company of the content playback apparatus 1 is included in the upper 3 bytes of the 8-byte device identifier ID1 (“organization identifier” in the figure). The remaining 5 bytes ("extended identifier" in the figure) are stored such that values that do not overlap among the plurality of content reproduction apparatuses 1 manufactured by each manufacturer are stored. In this case, the method shown in FIG. 9 is based on EUI-64 of IEEE (Institute of Electrical and Electronics Engineers).

  On the other hand, when the nonvolatile memory 4 of the content playback apparatus 1 is replaced, the manufacturer that manufactures the content playback apparatus 1 also for the special firmware FW loaded into the hardware right processing module 3 of the content playback apparatus 1 Is embedded with an organization identifier ID2.

  When this special firmware FW is loaded into, for example, the hardware right processing module 3 of the content reproduction apparatus 1, the hardware right processing module 3 responds accordingly to FIG. 10 according to the loaded special firmware FW. The inspection value generation / storage processing procedure RT3 as shown is executed.

  Here, the test value generation / storage processing procedure RT3 will be described with reference to FIG. In step SP31, the hardware right processing module 3 requests the CPU 6 to read out the device identifier ID1 stored in the ROM 2 of the content reproduction apparatus 1. In response to this, the CPU 6 reads out the device identifier ID1 including the organization identifier ID2 from the ROM 2 and inputs it to the hardware right processing module 3.

  When the device identifier ID1 is input in this way, the hardware right processing module 3 proceeds to step SP32, and the organization identifier ID2 included in the input device identifier ID1 and the hardware right processing module 3 are transferred to the hardware right processing module 3. The organization identifier ID2 embedded in the loaded special firmware FW is compared.

  In subsequent step SP33, as a result of the comparison in step SP32, the hardware right processing module 3 confirms that the organization identifier ID2 included in the device identifier ID1 matches the organization identifier ID2 embedded in the special firmware FW. Determine whether or not.

  If a positive result is obtained in step SP33, this means that the manufacturing company indicated by the organization identifier ID2 included in the device identifier ID1 and the manufacturing company indicated by the organization identifier ID2 embedded in the special firmware FW are identical. At this time, the hardware right processing module 3 proceeds to the next step SP34.

  In step SP34, the hardware right processing module 3 executes a calculation using the first calculation method for the device identifier ID1 input in step SP31, and uses the device identifier test value VM obtained as a result of this calculation. , And store it in the replaced nonvolatile memory 4.

  Next, in step SP35, the hardware right processing module 3 requests the CPU 6 to read the right information INF stored in the data storage medium 8 of the content reproduction apparatus 1. In response to this, the CPU 6 reads the right information INF from the data storage medium 8 and inputs it to the hardware right processing module 3.

  When the right information INF is input in this way, the hardware right processing module 3 proceeds to step SP36, and executes a calculation using the second calculation method for the input right information INF. The right information inspection value VR obtained as a result of the calculation is stored in the exchanged nonvolatile memory 4, and the process proceeds to the end step SP37 to end the inspection value generation / storage processing procedure RT3.

  On the other hand, if a negative result is obtained in step SP33, this means that the manufacturing company indicated by the organization identifier ID2 included in the device identifier ID1 and the manufacturing company indicated by the organization identifier ID2 embedded in the special firmware FW. And the hardware right processing module 3 moves to the end step SP37 and ends the inspection value generation / storage processing procedure RT3.

  Thus, according to the inspection value generation / storage processing procedure RT3, for example, as shown in FIG. 11, the content reproduction apparatus 1Y manufactured by the manufacturing company Y different from the manufacturing company X identified by the organization identifier ID2 in the special firmware FW is used. On the other hand, even if the special firmware FW is loaded, the content reproduction apparatus 1Y manufactured by the manufacturer Y newly generates a device identifier inspection value VM and a right information inspection value VR and generates the generated device identifier inspection value. The inspection value generation and storage process (steps SP34 to SP36) for storing the VM and the rights information inspection value VR in the nonvolatile memory 4 is not executed. Accordingly, in the case shown in FIG. 11, even if the special firmware FW leaks to a third party, damage caused by fraud using the special firmware FW is identified by the organization identifier ID2 in the special firmware FW. It can be limited only to the content reproduction apparatus 1X manufactured by the company X.

  As described above, the special firmware FW checks the device identifier based on the device identifier ID1 stored in the ROM 2 of the content playback device 1 and the right information INF stored in the data storage medium 8 of the content playback device 1. A check value generation and storage process (steps SP34 to SP36) for generating the value VM and the right information check value VR and storing the generated device identifier check value VM and right information check value VR in the nonvolatile memory 4 of the content reproduction apparatus 1; Manufacturing to be executed by the content reproduction device 1 and identified by the manufacturing company identified by the organization identifier ID2 embedded in the special firmware FW and the organization identifier ID2 stored in the ROM 2 of the content reproduction device 1 If the company does not match, this test value generation and storage process And so as not to perform the content reproduction apparatus 1.

  As a result, damage caused by fraud using the special firmware FW can be limited only to the content reproduction apparatus 1 manufactured by the manufacturing company identified by the organization identifier ID2 in the special firmware FW. As a result, it is possible to avoid an increase in damage to the copyright holder who authored the content data D. In addition, it is possible to clarify the management responsibility of each manufacturing company that should strictly manage the special firmware FW.

(3) Other Embodiments In the above-described embodiment, the case where the manufacturer that manufactured the content reproduction apparatus 1 is identified by the organization identifier ID2 has been described. However, the present invention is not limited to this. If a certain group can be identified, for example, the model of the content reproduction apparatus 1 may be identified.

  In the above-described embodiment, for example, audio data is applied as the content data D to be used by the user. However, the present invention is not limited to this, and various other data such as character information, video data, and programs can be used. Can be applied.

  Furthermore, in the above-described embodiment, the case where the production number of the content playback apparatus 1 is applied as the device identifier ID1 unique to the content playback apparatus 1 has been described, but the present invention is not limited to this, and the input / output interface unit 7 is not limited thereto. A physical address or the like uniquely assigned to (for example, NIC (Network Interface Card)) may be applied.

  Further, in the above-described embodiment, the case where the CPU 6 that executes various processes according to the program expanded in the RAM 11 is applied as the control means for controlling the hardware right processing module 3 and the like has been described. Not limited to this, an MPU (Micro Processing Unit) or the like may be applied.

  Furthermore, in the above-described embodiment, the case where the number of times the content data D can be reproduced is described in the right information INF indicating whether or not there is a right to use the content data D has been described. Not limited to this, for example, when the number of times that the content data D can be checked out to be lent out to another device is indicated, or when the number of times that the content data D can be copied to another device is indicated Etc.

  Furthermore, in the above-described embodiment, the content reproduction device 1 executes the content reproduction process RT1d for reproducing the content data D when the right information INF indicates that the content data D has a right to use. However, the present invention is not limited to this, and as long as the content data D is used by the user, a checkout process for outputting the content data D so as to be lent out to another device may be executed. A copy process for copying the content data D to another device may be executed.

  Further, in the above-described embodiment, the device identifier inspection calculated by using the first calculation method from the device identifier ID1 stored in the ROM 2 as data to be stored so as not to be read out separately from the right information inspection value VR. Although the case where the value VM is applied has been described, the present invention is not limited to this. For example, the device identifier ID1 itself stored in the ROM 2 or the device identifier ID1 stored in the ROM 2 is used to use another method. Various other data can be applied as long as it corresponds to the device identifier ID1 stored in the ROM 2, such as a calculated value.

  Furthermore, in the above-described embodiment, the case where the content reproduction apparatus 1 acquires the content data D from the server SV of the content provider via the Internet NT has been described as a method for acquiring the content data D. However, the present invention is not limited to this. For example, data stored in a data recording medium (CD (Compact Disc), DVD (Digital Versatile Disc, etc.)) may be read and acquired.

  Furthermore, in the above-described embodiment, the hardware right processing module 3 and the nonvolatile memory 4 provided on or outside the circuit board constituting the hardware right processing module 3 are applied as the signal processing circuit. However, the present invention is not limited to this, and various other configurations can be applied.

  Furthermore, in the above-described embodiment, the hardware right processing module 3 as shown in FIG. 1 or the like is applied as a hardware module that controls the use of the content data D based on the right information INF of the content data D. However, the present invention is not limited to this, and various other configurations can be applied.

  Further, in the above-described embodiment, the first inspection value (device identifier inspection value VM) for checking the consistency of the device identifier ID1 transferred from the device (content reproduction device 1) on which the hardware module is mounted; A nonvolatile memory 4 corresponding to a flash memory or the like is applied as a nonvolatile memory for storing a second inspection value (right information inspection value VR) for checking the consistency of the rights information INF related to the content data D. However, the present invention is not limited to this, and various other storage devices can be used as long as the device identifier inspection value VM and the right information inspection value VR can be stored separately so as not to be read out. Can be applied.

  Further, in the above-described embodiment, the hardware right processing module 3 reads the firmware (first type firmware) stored in the data storage medium 8 and performs the processing shown in FIG. 3 according to the read firmware. Although the case where the procedure RT1 is executed has been described, the present invention is not limited to this. For example, various other devices may execute the procedure RT1.

  Further, in the above-described embodiment, when repairing the content reproduction apparatus 1, the repair company loads the special firmware FW (second type firmware) into the hardware right processing module 3 of the content reproduction apparatus 1, Although it is assumed that the manufacturer loads the special firmware FW into the hardware right processing module 3 of the content playback device 1 when the content playback device 1 is manufactured, the present invention is not limited to this. For example, the content playback device 1 The user may load the special firmware FW into the hardware right processing module 3 of the content playback apparatus 1.

  The present invention can be used, for example, in a content reproduction apparatus that reproduces content data.

It is a basic diagram which shows the structure of the content reproduction apparatus in this Embodiment. It is a conceptual diagram (1) of a content reproduction apparatus. It is a flowchart which shows the process sequence of a hardware right processing module. It is a basic diagram which shows a mode (1) which prevents unauthorized use of content data. It is a basic diagram which shows a mode (2) which prevents unauthorized use of content data. It is a flowchart which shows a test value production | generation storage process procedure (1). It is a basic diagram which shows a mode that fraud by special firmware is performed. It is a conceptual diagram (2) of a content reproduction apparatus. It is a basic diagram which shows the structure of an apparatus identifier. It is an approximate line figure showing inspection value generation storage processing procedure (2). It is a basic diagram which shows a mode that the fraud by special firmware is prevented.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Content reproduction apparatus, 2 ... ROM, 3 ... Hardware right processing module, 4 ... Nonvolatile memory, 8 ... Data storage medium.

Claims (18)

A hardware module for controlling the use of the content data based on the rights information of the content data;
A first inspection value for checking the consistency of a device identifier transferred from a device on which the hardware module is mounted, and a second inspection value for checking the consistency of right information related to the content data are stored. Non-volatile memory for
The hardware module is
When the content data and the right information of the content data are acquired by the device, the second inspection value is calculated from the right information, and the calculated second inspection value is stored in the memory. And
When the first type of firmware is loaded, to check the integrity of the device identifier in accordance with the previously stored the first check value in the equipment identifier and the memory to be transferred from the device, in accordance with the check result, in response to the said second test value of the right information and in the memory of the content data to check the integrity of the right information, in accordance with the check result, in the right information Based on the content data,
When the second type of firmware is loaded, compared with the group identifier in the group identifier and the second type of firmware in the device identifier transferred from the device, in accordance with the comparison result, the first check value to check the integrity of the device identifier with stored again in the memory, from the rights information of the content data by calculating the second check value, the computed the second Re- storing test values in the memory
Signal processing circuit. The hardware module is
The first test value and the second test value are stored in the memory in a predetermined data array so that the second test value is separated from the first test value and is not read out.
The signal processing circuit according to claim 1. The hardware module is
As a result of checking the consistency of the device identifier according to the device identifier transferred from the device and the first test value in the memory when the first type of firmware is loaded, If it is determined that the device identifiers are not consistent, the content data is not checked for consistency, and the content data is not used.
The signal processing circuit according to claim 2. The hardware module is
As a result of checking the consistency of the device identifier according to the device identifier transferred from the device and the first test value in the memory when the first type of firmware is loaded, If it is determined that the device identifier is consistent, the integrity of the rights information is checked according to the rights information of the content data and the second inspection value in the memory. If it is determined that the data is consistent, whether or not the content data has a right to use is confirmed based on the right information.
The signal processing circuit according to claim 3. The aforementioned group identifier, Ru group the devices the hardware modules are implemented belongs shown
The signal processing circuit according to 請 Motomeko 1. The aforementioned hardware module, a calculation method for calculating the first check value from the device identifier Ru concealed
The signal processing circuit according to 請 Motomeko 1. The aforementioned hardware module, a calculation method for calculating the second check value from the rights information of the content data Ru concealed
The signal processing circuit according to 請 Motomeko 1. A storage unit for storing content data and rights information related to the content data;
A hardware module for controlling the use of the content data based on the rights information of the content data,
A non-volatile first memory for storing a device identifier;
A first check value to check the integrity of the device identifier, the non-volatile second memory for storing a second check value to check the integrity of the rights information of the content data
With
The hardware module is
When the content data and the right information of the content data are stored in the storage unit, the second check value is calculated from the right information, and the calculated second check value is calculated as the second check value. Stored in the memory of
When the first type of firmware is loaded, of the device identifier in accordance with the above previously stored in the first check value in the first of said device identifier stored in the memory and the second memory Check the integrity of, in accordance with the check result, checks the integrity of the rights information according to the above second check value for the right information and in said second memory of the content data, the check Based on the result, the use of the content data is controlled based on the right information,
When the second type of firmware is loaded, compared with the group identifier in the group identifier and the second type of firmware in said first memory stored the device identifier, the result of the comparison in response, the first check value to check the integrity of the device identifier with stored again in the second memory, and calculates the second check value from the rights information of the content data, the the computed the second check value stored again in the second memory
Content control device. The hardware module is
The first test value and the second test value are stored in the second memory in a predetermined data array so as not to be read out by separating the second test value from the first test value.
The content control apparatus according to claim 8. The hardware module is
When the first type of firmware is loaded, the consistency of the device identifier according to the device identifier stored in the first memory and the first inspection value in the second memory If the device identifier is determined to be inconsistent as a result of checking, the content data is not checked for consistency, and the content data is not used.
The content control apparatus according to claim 9. The hardware module is
When the first type of firmware is loaded, the consistency of the device identifier according to the device identifier stored in the first memory and the first inspection value in the second memory If the device identifier is determined to be consistent as a result of checking, the consistency of the right information is determined according to the right information of the content data and the second inspection value in the second memory. If it is determined that the rights information is consistent, whether or not the content data has a right to use is confirmed based on the rights information.
The content control apparatus according to claim 10. The aforementioned group identifier, Ru group the devices the hardware modules are implemented belongs shown
Content control apparatus according to 請 Motomeko 8. The aforementioned hardware module, a calculation method for calculating the first check value from the device identifier Ru concealed
Content control apparatus according to 請 Motomeko 8. The aforementioned hardware module, a calculation method for calculating the second check value from the rights information of the content data Ru concealed
Content control apparatus according to 請 Motomeko 8. Based on the right information of content data to a content control method of a hardware module for controlling the usage of the content data,
When the content data and the rights information of the content data are acquired by a device in which the hardware module is mounted, a second inspection value for checking the consistency of the rights information is calculated from the rights information. A first step of storing the calculated second inspection value in a non-volatile memory;
When the first type of firmware is loaded, stored in advance in the device identifier and the memory to be transferred from the upper Symbol equipment, in accordance with the first check value to check the consistency of the device identifier A second step of checking the consistency of the device identifier;
Depending on the check result in the second step, a third step of checking the consistency of the rights information according to the above second check value for the right information and in the memory of the content data,
A fourth step of controlling the use of the content data based on the right information according to the check result in the third step;
When the second type of firmware is loaded, a fifth step of comparing the group identifier in the group identifier and the second type of firmware in the device identifier transferred from the device,
Depending on the comparison result in the fifth step, the first check value to check the integrity of the device identifier with stored again in the memory, the second check value from the rights information of the content data by calculating the, Turkey content control method described above were the computed second check value comprising a sixth step of re-stored in the memory. Based on the right information of content data to a content control method of the content control apparatus having the hardware module adapted to control the usage of the content data,
When the content data and the right information of the content data are stored in the storage unit provided in the content control device, a second inspection value for checking the consistency of the right information is calculated from the right information. A first step of storing the calculated second inspection value in a non-volatile second memory;
When the first type of firmware is loaded, and the device identifier stored in a non-volatile first memory provided in the content control apparatus, stored in advance in the upper Symbol second memory, the device identifier A second step of checking the consistency of the device identifier according to the first inspection value for checking the consistency of
Depending on the check result in the second step, a third step of checking the consistency of the rights information according to the above second check value in the right information and the second memory of the content data When,
A fourth step of controlling the use of the content data based on the right information according to the check result in the third step;
When the second type of firmware is loaded, a fifth step of comparing the group identifier in the group identifier and the second type of firmware in said first memory stored the device identifier,
Depending on the comparison result in the fifth step, the first check value to check the integrity of the device identifier with stored again in the second memory, the second from the right information of the content data the test value is calculated for, Turkey content control method described above were the computed second check value comprising a sixth step of re-stored in the second memory. For the hardware module that controls the use of the content data based on the content data rights information,
When the content data and the rights information of the content data are acquired by a device in which the hardware module is mounted, a second inspection value for checking the consistency of the rights information is calculated from the rights information. A first step of storing the calculated second inspection value in a non-volatile memory;
When the first type of firmware is loaded, stored in advance in the device identifier and the memory to be transferred from the upper Symbol equipment, in accordance with the first check value to check the consistency of the device identifier A second step of checking the consistency of the device identifier;
Depending on the check result in the second step, a third step of checking the consistency of the rights information according to the above second check value for the right information and in the memory of the content data,
A fourth step of controlling the use of the content data based on the right information according to the check result in the third step;
When the second type of firmware is loaded, a fifth step of comparing the group identifier in the group identifier and the second type of firmware in the device identifier transferred from the device,
Depending on the comparison result in the fifth step, the first check value to check the integrity of the device identifier with stored again in the memory, the second check value from the rights information of the content data by calculating a content control program for the computed the second check value to execute a sixth step of re-stored in the memory. For a content control apparatus having a hardware module configured to control use of the content data based on content data right information,
When the content data and the right information of the content data are stored in the storage unit provided in the content control device, a second inspection value for checking the consistency of the right information is calculated from the right information. A first step of storing the calculated second inspection value in a non-volatile second memory;
When the first type of firmware is loaded, and the device identifier stored in a non-volatile first memory provided in the content control apparatus, stored in advance in the upper Symbol second memory, the device identifier A second step of checking the consistency of the device identifier according to the first inspection value for checking the consistency of
Depending on the check result in the second step, a third step of checking the consistency of the rights information according to the above second check value in the right information and the second memory of the content data When,
A fourth step of controlling the use of the content data based on the right information according to the check result in the third step;
When the second type of firmware is loaded, a fifth step of comparing the group identifier in the group identifier and the second type of firmware in said first memory stored the device identifier,
Depending on the comparison result in the fifth step, the first check value to check the integrity of the device identifier with stored again in the second memory, the second from the right information of the content data the test value by computing the content control program for the above were the computed second check value to execute a sixth step of re-stored in the second memory.

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