JP2001292136A - Copy control method and copy controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable system, which can arbitrarily control the copying of offered each information on a medium side, such as a large capacity recording medium and a communication medium and can always use offered information by legally copying ciphered information transferred from a derive to an information transmission means by using key information generated by an information reproducing device and by copying the information which is read from the drive by only the information reproduction device having the key information used for a ciphering processing. SOLUTION: An MPEG board 6 issues key information generated by the board to the DVD drive 4. The DVD drive 4 generates ciphered key information, based on the key information, ciphers offered information which is read from DVD 2 by the key information and transmits it to the MPEG board 6. The MPEG board 6 decodes the offered information, which has been ciphered by the key information generated in the board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to, for example, MPEG2
The present invention relates to a copy control method and a copy control apparatus applied to an information processing system having a function of reproducing provided information that reproduces and outputs information (referred to as provided information) such as movies and music that have been subjected to compression processing.

[0002] The present invention relates to, for example, CD-ROM, DVD
(Digital Video Disc) A copy control method and a copy capable of controlling the reproduction and use of the duplicate information when recording and reproducing the information recorded on a large-capacity recording medium such as a digital video disc as the duplicate information by the specific control information recorded on the medium. It relates to a control device.

[0003] The present invention is applied to a computer system having a function of receiving provided information such as a movie or music via communication means and reproducing and outputting the provided information, and controlling copying of information provided by communication. The present invention relates to a method and a replication control device.

[0004]

2. Description of the Related Art In a system for reproducing and outputting information (referred to as provided information) of a movie, music, etc. provided by the movie industry or the music industry and compressed by, for example, MPEG2 or the like, an unauthorized copy is performed. Copy protection technology is required to prevent this.

[0005] In particular, in a system for reproducing and outputting provided information having a high added value by computer processing as described above, it is not a copy protection technique that can be canceled by computer processing, but an unauthorized copy is surely performed. It is essential to establish a reliable copy protection technology that can be prevented.

In this type of conventional copy protection technology, illegal copy prevention information is also recorded on a recording medium such as a CD-ROM in which provided information is recorded, and the illegal copy prevention information is read together with the provided information to read the illegal information. The information is transmitted to a duplication prevention device, and the provided information is subjected to duplication prevention processing to prevent illegal duplication.

However, in such a conventional copy protection technique, copy protection processing is not performed until the provided information recorded on the disc is transmitted to the unauthorized duplication prevention apparatus. In a system configuration in which a computer device intervenes as a transmission device between the reading device and the reproducing device, intentional unauthorized duplication of the provided information is permitted.

As described above, conventionally, in a system in which a computer intervenes in the delivery of provided information, a highly reliable copy protection technique capable of reliably preventing unauthorized duplication has not been established. However, when attempting to construct a system in which a part of the provided information can be selectively taken into a computer and used, illegal copying of all the provided information is permitted.

[0009]

As described above, conventionally, in a system in which a computer intervenes in the delivery of information such as movie information and music information provided by a large-capacity recording medium or the like, illegal copying is performed. Reliable copy protection technology has not been established that can reliably prevent data from being provided, especially when trying to construct a system that can selectively use part of the provided information in a computer and use it. There has been a problem that unauthorized duplication of information is permitted.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a highly reliable copy control method and a copy control device that can reliably prevent unauthorized duplication even in a system in which a computer intervenes in the transfer of information provided by a large-capacity recording medium or the like. Aim.

Further, in the present invention, a large-capacity recording medium,
Even in a system in which a computer device intervenes in the transfer of information provided by a communication medium, etc., the computer device does not show key information used for encryption and decryption processing, and the medium uses the copy for each provided information. It is an object of the present invention to provide a copy control method and a copy control device which can control arbitrarily, can use the provided information with high reliability and always valid copy.

[0012]

SUMMARY OF THE INVENTION The present invention relates to a system for duplicating a computer or the like in a system in which a device such as a computer or the like capable of performing duplication processing intervenes in the transfer of information provided by a large-capacity recording medium, a communication medium or the like. On a device capable of processing, since the information read from the medium is in a state of being encrypted with a specific key, it is possible to arbitrarily control whether or not the reproduced copy information can be reproduced.

According to the present invention, in a system in which an apparatus capable of performing a duplication process such as a computer intervenes in the transfer of information provided by a large-capacity recording medium, a communication medium, or the like, the duplication process of a computer or the like is enabled. Reliable and always legitimate reproduction of reproduction that can control the reproduction of reproduction information for each provided information on the medium side without directly showing the key information used for encryption and decryption processing to the device. To provide a copy control method and a copy control device capable of utilizing the information provided by the system. It should be noted that in the present invention, to temporarily record information provided by a large-capacity recording medium, a communication medium, and the like in a storage device and read and reproduce the information is referred to as “reproduction of duplicate information”.
It is called.

An information duplication control method according to the present invention is an information duplication control method applied to a system including a receiving device that receives information read by a transmitting device via a transmitting means, A step of generating and holding a common key in each of the transmitting device and the receiving device, and using the common key and the copy control information for controlling at least the copy read by the transmitting device in the transmitting device. Encrypting the information read by the transmitting device, transferring the encrypted information and the copy control information to the receiving device via the transmitting means,
Decrypting the encrypted information by using at least the copy control information and the common key received by the receiving device via the transmitting means.

[0015] Further, an information duplication control device according to the present invention is an information duplication control device applied to a system including a receiving device that receives information read by a transmitting device via a transmitting means. Means for generating and holding a common key in each of the transmitting device and the receiving device, copy control information for controlling at least a copy read by the transmitting device in the transmitting device, and the common key Means for encrypting the information read by the transmitting apparatus using: a means for transferring the encrypted information and the copy control information to the receiving apparatus via the transmitting means; and Means for decrypting the encrypted information using at least the copy control information and the common key received via the transmission means in the device. And it features.

Further, an information duplication control method according to the present invention is an information duplication control method applied to a system having a receiving device for receiving information read by a transmitting device via a transmitting means. Generating and holding a common key in each of the transmitting device and the receiving device;
The transmitting device encrypts at least the duplication control information for controlling duplication read by the transmitting device using the common key, and transfers the encrypted duplication control information to the receiving device via the transmitting unit. And decrypting the encrypted copy control information received via the transmission means using at least the common key in the receiving device.

An information duplication control device according to the present invention is an information duplication control device applied to a system including a receiving device that receives information read by a transmitting device via a transmitting means, Means for generating and holding a common key in each of the transmitting device and the receiving device, and encrypting copy control information for controlling a copy read by the transmitting device using at least the common key in the transmitting device, Means for transferring the encrypted copy control information to the receiving device via the transmitting means, and the encrypted copy control received via the transmitting means using at least the common key in the receiving device. Means for decoding information.

An information duplication control method according to the present invention is an information duplication control method applied to a system including a receiving device that receives information read by a transmitting device via a transmitting unit. Generating a first key based on a first random value in the transmitting device, generating a second key based on a second random value in the receiving device, and generating a second key based on a second random value in each of the transmitting device and the receiving device The first and second keys are exchanged with each other via the transmitting means, and the first and second keys exchanged with each other are used by the transmitting device and the receiving device to perform the first and second keys respectively. Generating and holding a common key; and generating a third key based on a third random value in the receiving device;
Using the first common key, the third key is encrypted, and the encrypted third key is transferred from the receiving device to the transmitting device. Generating and holding a second common key corresponding to the third key; and in the transmitting device, at least according to the copy control information for controlling the copy read by the transmitting device, the first common key. Selecting one of the common key and the second common key, and encrypting the information read by the transmitting device using the selected common key in the transmitting device. Transferring the encrypted information and the copy control information to the receiving device via the transmitting device; and receiving, at the receiving device, at least via the transmitting device. In accordance with the copy control information, said first
Selecting one of the common key and the second common key, and the receiving device decrypting the encrypted information using the selected common key. It is characterized by having.

By having the above-described copy control mechanism, even in a system in which a device such as a computer capable of performing a copy process intervenes in the transfer of information provided by a large-capacity recording medium, a communication medium, etc. It is possible to arbitrarily control the reproduction of the copy information for each provided information on the medium side without showing the key information used for the encryption and decryption processing to a device that can perform the copy processing such as It is possible to construct a system that can utilize the information provided by simple duplication.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a basic system configuration according to the first embodiment of the present invention. Here, a movie, a movie, and the like recorded on a large-capacity storage medium (DVD2) are shown.
The provided information passed from the drive (DVD drive 4) to the information transmitting means (PC1) is provided using the key information generated in the information reproducing apparatus (MPEG board 6) with the provided information such as music as a target of duplication prevention. By performing the encryption processing, the information reproducing apparatus (MP
An example in which only the EG board 6) can copy and reproduce information read by the drive (DVD drive 4) and permits one-generation copy is illustrated.

In FIG. 1, reference numeral 1 denotes a computer (PC) serving as an information transmitting means for transferring provided information read by a drive to an information reproducing apparatus. Selective loading, H
Stored in an external storage device 3 such as a DD or a DVD-RAM,
Enables processing such as editing and proofreading.

Reference numeral 2 denotes a DVD disk on which provided information such as a movie and music to be controlled for duplication is recorded. This DVD
2, the provided information is recorded after being compressed by, for example, MPEG2, and corresponding to the provided information,
Copy permission information (CGMS) as shown in FIG. 7 is recorded in a part of the media file management information block.

Reference numeral 4 denotes a drive device for reading information from the DVD 2, which is referred to as a DVD drive here. This D
The VD drive 4 has a function of receiving key information generated in the information reproducing apparatus and encrypting provided information read from the DVD 2 using the key information. FIG. 2 shows a specific configuration example of this function.

Reference numeral 6 denotes an information reproducing apparatus which receives the provided information read by the DVD drive 4 via the computer (PC) 1 and performs reproduction / output processing, and is referred to as an MPEG board here. The MPEG board 6 is equipped with an MPEG2 decoder, and decodes provided information that has been received via the computer (PC) 1 and has been subjected to MPEG2 compression processing to obtain reproduction output information. Further, the MPEG board 6 has a function of generating key information, transmitting the key information to the DVD drive 4, and decoding the provided information using the key information. FIG. 2 shows a specific configuration example of this function.

In the configuration shown in FIG. 1, the MPEG board 6 issues the key information generated by the board 6 to the DVD drive 4 and holds the key information as a decryption key.

The DVD drive 4 generates an encryption key using the key information, encrypts the provided information read from the DVD 2 using the key, and then processes the MPEG board via the computer (PC) 1. Send to 6.

The MPEG board 6 receives the provided information encrypted from the DVD drive 4 via the computer (PC) 1 and performs decryption processing using the decryption key generated by the board.

By providing such a copy control mechanism, only the MPEG board 6 having the key information used for the encryption processing can record and read the information read by the DVD drive 4 as the copy information.

That is, if the DVD drive 4 performs one type of encryption on one type (or one type) of provided information,
Even if a plurality of information reproducing apparatuses are connected via the information transmitting apparatus, reproduction and use of the duplicated information becomes impossible except for the information reproducing apparatus having the key information used for encryption.

In a specific configuration, the MPEG board 6
The key information sent to the DVD drive 4 is encrypted. Further, in a specific configuration, the exclusive control of duplication according to the above-described embodiment is selectively enabled by the above-mentioned duplication permission information (CGMS). To give a specific example, in FIG. When b1 is "01", exclusive control of the above-mentioned duplication is possible.

FIG. 2 is a block diagram showing a system configuration according to a second embodiment of the present invention. In this embodiment, data is read from a drive according to copy permission information (CGMS) recorded on a large-capacity recording medium. A copy-free copy permission level enabling reproduction of the copy information once recording the provided information to all the information reproduction devices, and a permission level allowing the reproduction of the copy information only in a specific information reproduction device, A system having a function of selectively switching the reproduction level of the above-described copy information to a permission level in which all the information reproduction apparatuses are not permitted is realized.

In FIG. 2, reference numerals 10 and 10A correspond to the computer (PC) 1 shown in FIG.
Is the CP of the computer that controls the entire system
U and 10A are the system buses. Here, CPU1
Under the control of 0, the duplication control processing as shown in FIGS. 3 to 6 is executed. Further, the CPU 10 includes a drive device 40
Selectively captures the provided copy-permitted information read from the information recording medium 20, stores it in the storage device 30, and enables processing such as editing and proofreading.

Reference numeral 20 denotes an information recording medium corresponding to the DVD 2 shown in FIG. 1. The information recording medium 20 is recorded by being compressed by MPEG2 and recorded in a part of the media file management information block in accordance with the provided information. And copy permission information (CGMS) as shown in FIG.

Reference numeral 30 denotes a storage device corresponding to the external storage device 3 shown in FIG. 1, which is used for storing, editing, and proofreading the duplicate information.

A drive device 40 corresponds to the DVD drive 4 shown in FIG. Here, it is configured to include encryption generation devices 41 and 44, registers 42, 43, 45, 48, and 51 for storing encryption keys, a reading device 46, encryption devices 47 and 49, a decryption device 50, and the like.

The encryption generation device 41 generates an encryption key (1) based on a random value using a random number generation device.

The register 42 holds the encryption key (1) generated by the encryption generator 41. The register 43 holds the encryption key (2) received from the playback device 60 via the system bus 10A.

The encryption generating device 44 generates an encryption key (3) using the encryption key (1) and the encryption key (2). The register 45 stores the encryption key (3) generated by the encryption generation device 44.
Hold.

The reading device 46 reads information recorded on the information recording medium 20. Here, copy permission information (CGMS) as shown in FIG. 7 indicating the provision information of a movie, music or the like to be subjected to the copy control and the copy permission level of the provision information.
Read each.

The encryption device 47 converts the provided information read from the information recording medium 20 according to the copy permission information (CGMS).
Using the encryption key (3) stored in the register 45 or the provided information encryption key (5) stored in the register 51, the encryption processing is performed, or the encryption processing is not performed and the encryption processing is performed via the system bus 10A. It is sent to the playback device 60.

The register 48 holds the copy permission information (CGMS) read from the information recording medium 20. The encryption device 49 transmits the copy permission information (CG
MS) and sends it to the playback device 60 via the system bus 10A.

The decryption device 50 decrypts the encrypted device-specific provided information encryption key (5) received from the playback device 60. The register 51 holds the encryption key (5) decrypted by the decryption device 50.

Reference numeral 60 denotes an apparatus for reproducing provided information corresponding to the MPEG board 6 shown in FIG. 1, which is provided with an MPEG decoder and which receives an MPEG-2 signal received via the system bus 10A.
The reproduction information is obtained by decoding the provided information which has been subjected to the compression processing. Here, the encryption generation devices 61 and 64, the registers 62, 63, 65, 69, 71,
72, decoding devices 66 and 67, MPEG2 decoder 6
8. It comprises an encryption device 70 and the like.

The encryption generation device 61 generates an encryption key (2) based on a random value using a random number generation device.

The register 62 holds the encryption key (1) received from the drive device 40 via the system bus 10A. The register 63 holds the encryption key (2) generated by the encryption generation device 61.

The encryption generating device 64 generates an encryption key (4) using the encryption key (1) and the encryption key (2). The register 65 stores the encryption key (4) generated by the encryption generator 64.
Hold.

The decryption device 66 decrypts the encrypted copy permission information (CGMS) received from the drive device 40 via the system bus 10A of the computer body.

The decryption device 67 transmits the provided information received from the drive device 40 via the system bus 10A of the computer main unit to the copy permission information (C) stored in the register 71.
GMS), using the encryption key (4) stored in the register 65 or the provided information decryption key (6) stored in the register 72 to perform decryption processing, or perform MPEG2 decoding without performing decryption processing. 68.

The MPEG2 decoder 68 includes the decoding device 6
The provided information decoded in step 7 is decoded, and the provided information that can be reproduced and output is sent to the display controller 80.

The register 69 holds the provided information encryption key (5) unique to the device. The encryption device 70 has a register 69
And encrypts the provided information encryption key (5) unique to the device and sends it to the drive device 40.

The register 71 holds the copy permission information (CGMS) decrypted by the decryption device 66.

The register 72 holds a provided information decryption key (6) (for example, having a common value) that is paired with the device-specific provided information encryption key (5) stored in the register 69.

Reference numeral 80 denotes a display controller for displaying and outputting the provided information output from the MPEG2 decoder 68 to a display device 81.

The key values of the registers 45 and 65 are cleared and rewritten at least at the start or end of reproduction. Further, the key values of the registers 69 and 72 are not limited to fixed values, and may be rewritten, for example, at the start of reproduction.

FIGS. 3 to 6 are flow charts showing the processing procedure in the second embodiment of the present invention. FIGS. 3 and 4 show various key information for encryption and decryption processing, respectively. 5 and FIG. 6 are flowcharts showing the copy control processing procedure when reading the provided information.

FIG. 7 shows the copy permission information (C) in the media file management information block recorded on the information recording medium 20.
FIG. 3 is a diagram showing an information format for explaining GMS). Here, when b0 and b1 of the CGMS are “00”, all reproduction devices 60 are permitted to reproduce the copy information, and when b0 and b1 are “01”, the reproduction information is used when the provision information is read. Reproduction of exclusive copy information is permitted only to the playback devices, and when b0 and b1 are "11", reproduction of the copy information is prohibited for all the playback devices 60.

Here, the operation of the second embodiment of the present invention will be described with reference to FIGS.

First, with reference to the flowcharts shown in FIGS. 3 and 4, the setting processing of various key information for encryption and decryption processing will be described.

When the system is started according to the reproduction instruction, the encryption generating device 41 of the drive device 40 generates an encryption key (1) based on a random value (step 40a in FIG. 3).

The encryption key (1) generated by the encryption generation device 41 is held in the register 42,
It is set in the register 62 of the playback device 60 under the control of U10 (step 10a in FIG. 3, step 60a in FIG. 4).

The encryption generation device 61 of the reproduction device 60 also generates the encryption key (2) based on the random value (step 60b in FIG. 4).

The encryption key (2) generated by the encryption generation device 61 is held in the register 63,
It is set in the register 43 of the drive device 40 under the control of U10 (steps 10b and 40b in FIG. 3).

The encryption generation device 44 of the drive device 40 uses the encryption key (1) stored in the register 42 and the register 43
Key (3) using the encryption key (2) stored in the
Is generated and set in the register 45 (step 40 in FIG. 3).
c).

Further, the encryption key 64 stored in the register 62 and the register 63
Key (4) using the encryption key (2) stored in
Is generated and set in the register 65 (FIG. 4, step 6).
0c).

The reading device 46 of the drive device 40 reads the copy permission information (CGMS) from the information recording medium 20 and sets it in the register 48 (step 40d in FIG. 3).

The encryption device 49 uses the encryption key (3) stored in the register 45 to encrypt the copy permission information (CGMS) set in the register 48 (FIG. 3).
Step 40e. The encrypted copy permission information (CGMS) is transferred to the decryption device 66 of the playback device 60 under the control of the CPU 10 (step 10c in FIG. 3).

The decryption device 66 decrypts the encrypted copy permission information (CGMS) received from the drive device 40 using the encryption key (4) stored in the register 65, and (Step 60d in FIG. 4).

A control device (not shown) in the reproducing device 60 includes:
The contents of the copy permission information (CGMS) stored in the register 71 are determined, and b0 and b1 of the copy permission information (CGMS) are determined.
Is "01" and recognizes that only the reproducing apparatus used for reading the provided information is permitted to reproduce the exclusive copy information, the encrypting apparatus 70 is started (step 60e (Yes) in FIG. 4). ).

As a result, the encryption device 70 sets the register 65
The encryption key (4) stored in the register 69 is used to encrypt the device-specific provided information encryption key (5) fixedly stored in the register 69 (step 60g in FIG. 4).

Further, b0, b of the copy permission information (CGMS)
If 1 is not "01", the provided information encryption key (5)
Is generated (step 60f in FIG. 4).

The CPU 10 transfers the provided information encryption key (5), which has been subjected to the encryption processing, to the decryption device 50 in the drive device 40 (step 10d in FIG. 3).

The decrypting device 50 decrypts the encrypted device-specific provided information encryption key (5) received from the reproducing device 60 and sets the decrypted information in the register 51.

With the above processing, the setting processing of various key information for the encryption and decryption processing is completed.

Next, with reference to the flowcharts shown in FIGS. 5 and 6, the copy control processing at the time of reading the provided information will be described.

The CPU 10 gives an instruction to read the provided information to the drive device 40 (step S1 in FIG. 5).

When a control device (not shown) in the drive device 40 receives a read instruction from the CPU 10, the read device 4
6 starts. The reading device 46 controls the drive of the information recording medium 20 and provides the provided information (MPE) from the information recording medium 20.
G2 data) and the copy permission information (CGMS) are read (step S2 in FIG. 5).

The copy permission information (CGMS) read from the information recording medium 20 is stored in the register 48 and then supplied to the encryption device 47.

The encryption device 47 determines the contents of the copy permission information (CGMS) stored in the register 48, and
When b0 and b1 of S are "00", the provided information is output (pass-through) as it is without encryption processing, and "01"
, The provided information is encrypted using the device-specific provided information encryption key (5) stored in the register 51, and if "11", the provided encryption key (3) stored in the register 45 is used. Is used to encrypt the provided information (see FIG. 5).
Steps S3 to S7).

The provided information (MPEG2 data) output from the encrypting device 47 is transferred to the decrypting device 67 in the reproducing device 60 via the system bus 10A (step S8 in FIG. 5).

The decrypting device 67 of the reproducing device 60 sends the information (MPEG2) provided by the encrypting device 47 in the drive device 40.
Data), the content of the copy permission information (CGMS) stored in the register 71 is determined, and b0,
When b1 is "00", the provided information is output (pass-through) without decryption processing, and when "1", the provided information encryption key (6) unique to the device stored in the register 72 is stored in the register 72. The provided information is decrypted using “1”.
If it is 1 ", the provided information is decrypted using the encryption key (4) stored in the register 65 (steps S11 to S16 in FIG. 5).

The provided information (MPEG2 data) output from the decoding device 67 is decoded by the MPEG2 decoder 68, sent to the display controller 80, and displayed on the display device 81 (step S1 in FIG. 5).
7).

At this time, the CPU 10 sets the copy permission information (C
When b0 and b1 of the GMS are “00”, the provided information (MPEG2 data) is fetched into the storage device 30, so that the duplicated information can be arbitrarily reproduced and output without specifying the reproducing device.

Further, b0, b of the copy permission information (CGMS)
When 1 is "01", the provided information (MPEG2 data) is taken into the storage device 30, and the provided information encryption key (5) unique to the device subjected to the encryption processing is paired with the device-specific provided information encryption key (5). Only the reproducing device 60 having the provided information encryption key (6) can reproduce the duplicated information.

At this time, the copy information is stored in the storage device 30 together with the encryption key (6) stored in the register 72, so that the reproduction information can be stored in the register 7.
Even if the key value of 2 is rewritten, the stored key information is read out and reset in the register 72, so that the corresponding copy information can be reproduced.

Also, b0, b of the copy permission information (CGMS)
When 1 is "11", even if the provided information (MPEG2 data) is fetched into the storage device 30 as copy information, the value of the encryption key (4) has already been changed during reproduction, so that the copy information is decrypted. Therefore, the duplication information cannot be reproduced in all the reproducing apparatuses.

At this time, each time the contents of the copy permission information (CGMS) are switched, the registers 69 and 72 are synchronized with the change.
, Or the key values of the registers 45 and 65 are newly set, whereby a copy protection mechanism that is more reliable and enables precise permission control in units of arbitrary information amount can be realized.

As described above, the information providing side can perform encryption for each provided information (for each title of a movie or music) and cannot read information easily with a computer or the like. The replication control of the provided information, which is highly reliable and highly used by computer processing or the like, is established.

Further, since the information read by the computer or the like can be reproduced only by the information reproducing apparatus used at the time of reading, the duplication information can be used legitimately. Use can be eliminated.

As described above, according to the embodiment of the present invention, even in a system in which a computer device intervenes in the transfer of information provided by a large-capacity recording medium or the like, the computer device performs encryption and decryption processing. It is possible to construct a highly reliable system that can always use the provided information by valid duplication without disclosing the key information used for the information.

In the above-described embodiment, a DVD, a CD-RO, which requires a drive device, is used as an information providing medium.
Although a large-capacity disk such as M is taken as an example, the present invention can be applied to a system configuration in which an information providing medium exists outside via a communication line, for example, as in the above embodiment. In this case, the reading device 46 in the drive device 40 shown in FIG.
The components can be easily realized by providing the components other than the above in an external information providing device that is a communication destination, and replacing the signal path indicated by a broken line in FIG. 2 with a communication path.

In the above embodiment, the copy permission information (CGMS) and the device-specific provided information encryption key (5) are encrypted and transferred, respectively. Instead, the encryption processing can be omitted according to the required reliability.

In the second embodiment described above, each of the drive device 40 and the information reproducing device 60 generates primary key information based on random information. However, the present invention is not limited to this. Drive device 40
Alternatively, one of the playback devices 60 generates primary key information based on random information, and based on the key information, the drive device 40 and the playback device 60 generate temporary secondary key information, respectively. In other words, any configuration may be used as long as the drive and the information reproducing apparatus temporarily generate key information related to each other using random information.

In the above embodiment, the playback device 60
In this configuration, the device-specific provided information encryption key (5) and the device-specific provided information decryption key (6) are provided independently of each other, and are stored separately in the registers 69 and 72. Not limited to, device-specific provided information encryption key (5)
And the decryption key (6) may use common key information. In short, in order for the reproducing device 60 to perform a decryption process on the input provided information, the encryption method and the encryption method of the input provided information are used. It is only necessary to be able to grasp the contents of the activation key.

In the second embodiment, a device-specific provided information encryption key (6) is paired with a device-specific provided information encryption key (5) used for the encryption processing. Although a copy control mechanism that allows only one generation copy, which can reproduce a copy only by the reproduction device 60, and a copy control mechanism that disables reproduction of the copy in all the reproduction devices are selectively used, For example, a configuration that selects a copy-free copy permission mode and a copy permission mode that disables reproduction of a copy in all playback devices, or a copy-free copy permission mode and a one-generation copy permission mode And any combination of duplication permission modes, such as a configuration for selecting.

Further, in the above-described embodiment, a system in which a computer intervenes in the delivery of provided information provided by a large-capacity recording medium, a communication medium, or the like is intended, but regardless of the system configuration, provided information is provided. Even if the system configuration does not directly involve a computer in the transfer of the information, a drive for reading the provided information from a recording medium such as an MD, a CD-ROM, or a DVD, or a communication medium having a function of transmitting the provided information, and reproducing the read data. An arbitrary copy control mechanism described in the above embodiment can be applied to an interface portion between devices capable of copying provided information between the device and the device that performs the copy.

Further, in this embodiment, provided information such as movies and music compressed by MPEG2 is taken as an example. However, the present invention is not limited to this, and information to be reproduced includes data compressed by MPEG1 or MPEG4. The present invention can also be applied to a system configuration that performs the above.

[0098]

As described above in detail, according to the present invention, there is provided a system in which a copy-capable device such as a computer intervenes in the transfer of information provided by a large-capacity recording medium, a communication medium, or the like. , Without having to show the key information used for encryption and decryption processing to a device such as a computer capable of duplicating processing, the medium can arbitrarily control the use of duplication for each provided information, and is highly reliable and always valid It is possible to provide a copy control method and a copy control device capable of utilizing information provided by proper copying.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic system configuration according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a system configuration according to a second embodiment of the present invention.

FIG. 3 is a flowchart illustrating a processing procedure according to a second embodiment of the present invention.

FIG. 4 is a flowchart showing a processing procedure according to a second embodiment of the present invention.

FIG. 5 is a flowchart showing a processing procedure according to the second embodiment of the present invention.

FIG. 6 is a flowchart illustrating a processing procedure according to the second embodiment of the present invention.

FIG. 7 is a diagram showing an information format for explaining copy permission information (CGMS) in a media file management information block recorded on the information recording medium 20 according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Computer apparatus (PC) 2 ... DVD (mass storage medium) 3 ... External storage apparatus 4 ... DVD drive (drive apparatus) 6 ... MPEG board (information reproducing apparatus) 10 ... CPU 10A ... System bus 20 ... Information recording medium DESCRIPTION OF SYMBOLS 30 ... Storage device 40 ... Drive device 41, 44 ... Encryption generation device 42, 43, 45, 48, 51 ... Register 46 ... Reading device 47, 49 ... Encryption device 50 ... Decryption device 60 ... Reproduction device 61, 64 ... Encryption generating device 62, 63, 65, 69, 71, 72 Register 66, 67 Decryption device 68 MPEG2 decoder 70 Encryption device.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/92 H04N 5/91 P 5/92 H

Claims (15)

[Claims] An information duplication control method applied to a system including a receiving device that receives information read by a transmitting device via a transmitting means, wherein the transmitting device and the receiving device each include: Generating and holding a common key; and information read by the transmitting device using the common key and copy control information for controlling at least the copy read by the transmitting device in the transmitting device. And transferring the encrypted information and the copy control information to the receiving device via the transmitting means, and the copy control information received by the receiving device via at least the transmitting means. Decrypting the encrypted information using the common key. 2. The method according to claim 1, wherein said generating step includes a step of generating at least two types of values for said common key. 3. The information duplicating method according to claim 2, wherein said encrypting step includes a step of selecting and determining one of said two types of values in accordance with a value of said duplication control information. Control method. 4. The generating step includes: generating a first key based on a first random value in the transmitting device; and generating a second key based on a second random value in the receiving device. And a first generated by each of the transmitting device and the receiving device.
And mutually exchanging a second key via the transmitting means, and using the mutually exchanged first and second keys, a first key held by each of the transmitting device and the receiving device. 4. The method according to claim 3, further comprising the step of generating a common key. 5. An information duplication control device applied to a system including a receiving device for receiving information read by a transmitting device via a transmitting means, wherein the transmitting device and the receiving device each include: Means for generating and holding a common key respectively, and read by the transmitting device using the common key and copy control information for controlling at least the copy read by the transmitting device in the transmitting device. Means for encrypting the encrypted information, means for transferring the encrypted information and the copy control information to the receiving apparatus via the transmitting means, and wherein the receiving apparatus receives the information via at least the transmitting means. Means for decrypting the encrypted information using the copy control information and the common key. 6. An apparatus according to claim 5, wherein said generating means includes means for generating at least two types of values for said common key. 7. The information duplication method according to claim 6, wherein said encryption means includes means for selecting and determining one of said two types of values in accordance with a value of said duplication control information. Control device. 8. The means for generating a first key based on a first random value in the transmitting device, and a means for generating a second key based on a second random value in the receiving device. And a first generated by each of the transmitting device and the receiving device.
Means for mutually exchanging a second key with the second key via the transmitting means, and a first key held by each of the transmitting device and the receiving device using the first and second keys exchanged with each other. 8. An apparatus according to claim 7, further comprising: means for generating a common key. 9. A method for controlling duplication of information applied to a system including a receiving device that receives information read by a transmitting device via a transmission unit, wherein the method includes the steps of: Generating and holding a common key, encrypting the copy control information for controlling the copy read by the transmission device using at least the common key in the transmission device, and encrypting the encrypted copy control information. Transferring to the receiving device via the transmitting means; and decrypting the encrypted copy control information received via the transmitting means using at least the common key in the receiving device. And a method of controlling duplication of information. 10. The generating step includes: generating a first key based on a first random value in the transmitting device; and generating a second key based on a second random value in the receiving device. And a first generated by each of the transmitting device and the receiving device.
And mutually exchanging a second key via the transmitting means, and using the mutually exchanged first and second keys, a first key held by each of the transmitting device and the receiving device. The method according to claim 9, further comprising the step of: generating a common key. 11. The method according to claim 11, wherein the selecting step includes a step of selecting and determining a first value of the common key when the copy control information indicates that reproduction of the copy is prohibited. 10. A method for controlling duplication of information according to item 10. 12. An information duplication control device applied to a system including a receiving device that receives information read by a transmitting device via a transmitting means, wherein each of the transmitting device and the receiving device includes: Means for generating and holding a common key; encrypting copy control information for controlling a copy read by the transmission device using at least the common key in the transmission device; and encrypting the encrypted copy control information. Means for transferring to the receiving apparatus via the transmitting means, and means for decrypting the encrypted copy control information received via the transmitting means using at least the common key in the receiving apparatus. A duplication control device for information. 13. The means for generating a first key based on a first random value in the transmitting device, and a means for generating a second key based on a second random value in the receiving device. And a first generated by each of the transmitting device and the receiving device.
Means for mutually exchanging a second key with the second key via the transmitting means, and a first key held by each of the transmitting device and the receiving device using the first and second keys exchanged with each other. 13. The information duplication control device according to claim 12, further comprising: means for generating a common key. 14. The apparatus according to claim 1, wherein said selection determining means includes means for selecting and determining a first value of said common key when said copy control information indicates that reproduction of a copy is prohibited. 13. The information copy control device according to item 13. 15. An information duplication control method applied to a system including a receiving device that receives information read by a transmitting device via a transmitting unit, wherein the transmitting device converts the information to a first random value. Generating a first key based on a second random value in the receiving device, and transmitting the first and second keys generated in the transmitting device and the receiving device, respectively, to the receiving device. Generating and holding a first common key in each of the transmitting device and the receiving device using the first and second keys exchanged with each other through means; The receiving device generates a third key based on a third random value, and uses the first common key to generate the third key.
And the encrypted third key is transferred from the receiving device to the transmitting device, and each of the transmitting device and the receiving device corresponds to a second key corresponding to the third key.
Generating and holding the common key of the first common key and the second common key in the transmitting device in accordance with at least copy control information for controlling a copy read by the transmitting device. Selecting at least one of the following, and in the transmitting device, encrypting the information read by the transmitting device using the selected common key, and encrypting the encrypted information and the copy. Transferring the control information to the receiving device via the transmitting means; and in the receiving device, at least according to the copy control information received via the transmitting means, the first common key and the second Selecting one of a common key, and the receiving device, wherein the encrypted information is encrypted using the selected common key. Decoding the information.