JP2002372910A - Authenticating and reproducing method for contents information and contents information authenticating and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contents reproducing device extracting contents to which unauthorized signature information is attached by verifying a signature and denying its reproduction and reproducing only digital contents to which right signature information is attached by a simple signature verification. SOLUTION: By collating signature information recorded on a recording medium together with the digital contents with the unauthorized signature information to be an unauthorized object stored in a storage medium beforehand, when matching information is present, the reproduction of the contents is denied or stopped without performing the processing of authentication. Also, when the matching unauthorized signature information is not present, the signature information is verified. When it is verified as the unauthorized signature information, the unauthorized content information is additionally stored in the storage medium as the unauthorized signature information and the reproduction of the contents is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for authenticating and reproducing digital contents and a recording medium on which the digital contents are recorded. More particularly, the present invention relates to a method for verifying improper signature information and a process when the digital contents are reproduced. The present invention relates to a method, and to an apparatus equipped with the method.

[0002]

2. Description of the Related Art Conventionally, a method of performing authentication by a signature has been generally used as an effective means for preventing the use of a recording medium in which digital contents protected by copyright are illegally copied. . The authenticated playback method is
In addition to digital content, signature information indicating that the recording medium or the content is legitimate is recorded on the recording medium, and permission or rejection of content reproduction is given based on the signature information so that the content can be reproduced. This controls the reproduction.

In an apparatus for controlling the reproduction of the digital content, it is first verified whether or not the signature is valid, and the reproduction of the digital content is performed only when the signature is determined to be valid. ing.

[0004] Japanese Patent Laid-Open No. 2000-22680, "Digital content distribution method and recording medium on which content is reproducibly recorded," discloses digital content decryption at least partially encrypted based on a signature verification result. A method is disclosed in which it is determined whether or not a key required for encryption is decrypted, and when the information such as a signature is determined to be valid, the content is decrypted. The method of doing is known.

[0005]

However, in a system using a signature as used in the above method, when a security level higher than a certain level is to be secured for protection against falsification of signature information, the signature and its signature are used. The amount of data required for the protection of the signature becomes large, and the amount of computation used for the signature authentication also increases, and the authentication process becomes complicated.

[0006] In order to authenticate the signature, a work environment for signal processing such as using a personal computer having sufficient processing capability is required. It is not preferable to mount a computer system having such a high processing capacity on the apparatus, which increases the price of the reproducing apparatus, which is not preferable. Usually, the processing capacity for signature authentication is often reduced.

In such a digital content reproducing apparatus having only a signature authentication function having a low processing capability, a long time is required until the content is reproduced and displayed after the reproduction operation is performed by the user, and furthermore, Such a complicated signature authentication process must be performed every time the content is played back, and such a digital content playback device takes a long time from when the playback operation is started to when the content is displayed. There were problems such as an obstacle to realizing a user-friendly function.

Therefore, the present invention provides a method for reproducing information from a recording medium on which signature information indicating that the content and the recording medium on which the content is recorded is legitimate content and the recording medium is used. In the digital content reproducing method in which authentication is performed and the reproduction of the content is prohibited or stopped when the content is determined to be an illegal content or a medium, the authentication information recorded on the recording medium is stored in advance in the storage medium. In this case, the reproduction of the content is not permitted or stopped without performing the above-mentioned authentication processing when the matching information exists by comparing the signature information with the signature information to be fraudulent.

When there is no matching information,
Performs authentication work on the signature of the new content and the recording medium, and when the content and the medium are authenticated, stores the signature information to be improperly stored in a removable medium or a memory element. Or, the signature information is stored in a storage device of a server system connected to a network via a network interface, so that the signature information to be improperly stored in a storage medium is updated in advance, thereby reproducing the content. It is an object of the present invention to provide a method for authenticating and reproducing content information in which the authentication operation of signature information performed at the time of the above is simplified, and a configuration of a content information authenticating and reproducing apparatus equipped with the method.

[0010]

The present invention comprises the following means 1) to 10) to solve the above-mentioned problems. That is,

1) A method for authenticating and reproducing content information for reproducing only a digital content recording medium on which digital content produced based on a proper right and signature information relating to authentication of a creator of the digital content are recorded. Wherein the digital content recording medium is reproduced to obtain reproduction signature information relating to the signature information.
(41), comparing the reproduction signature information with an unauthorized signature information group that accumulates and stores the unauthorized signature information attached to the digital content produced without the basis of the legitimate rights, and A second step (4) of detecting whether or not the information matches any one of the unauthorized signature information groups;
7) when the reproduction signature information matching the unauthorized signature information is detected in the second step, a signal for stopping reproduction of the digital content recording medium is supplied; If no match is detected, a third step (46) of verifying whether or not the reproduction signature information is signature information relating to the authentication of the creator of the digital content, and performing the reproduction signature by the signature verification If the validity of the information is not verified, the reproduction signature information is additionally stored in the unauthorized signature information group.
(51). A method for authenticating and reproducing content information.

2) Authentication reproduction of content information for reproducing only digital content transmission information in which digital content produced based on a proper right and signature information relating to authentication of a creator of the digital content are transmitted. A first step (49) of reproducing the digital content transmission information to obtain reproduction signature information related to the signature information; and a method of illegally attaching to the digital content produced without a right. A second step (47) of comparing an unauthorized signature information group in which signature information is cumulatively stored with the reproduced signature information to detect whether the reproduced signature information matches any of the illegal signature information groups; ), And when the reproduction signature information matching the unauthorized signature information is detected in the second step, the digital content A signal for stopping reproduction of the transmission information is supplied, and when a match with the unauthorized signature information is not detected, whether or not the reproduction signature information is signature information related to authentication of a creator of the digital content is determined. A third step (46) of performing signature verification, and when the validity of the reproduction signature information is not verified by the signature verification,
And a fourth step (51) of additionally storing the reproduction signature information in the unauthorized signature information group.

3) A content information authenticating / reproducing apparatus for reproducing only a digital content recording medium on which digital content produced based on a proper right and signature information relating to authentication of a creator of the digital content are recorded. Recording signal reading means (41) for reproducing the digital content recording medium to obtain reproduction signature information relating to the signature information; and unauthorized signature information attached to digital content produced without a right. A signature information comparing means (47) for comparing an unauthorized signature information group in which the accumulated signatures are stored with the playback signature information to detect whether the playback signature information matches any of the unauthorized signature information groups. When the signature information comparing means detects the reproduction signature information that matches the unauthorized signature information, A signal for stopping the reproduction of the content recording medium is supplied, and when the coincidence with the illegal signature information is not detected, whether or not the reproduction signature information is signature information related to authentication of a creator of the digital content is determined. Signature verification means (46) for verifying the signature of the signature information; and signature information recording means (additional storage of the reproduction signature information in the unauthorized signature information group when the validity of the reproduction signature information is not verified by the signature verification means). 51). A content information authenticating and reproducing apparatus comprising at least:

4) A content information authenticating / reproducing apparatus for reproducing only digital content transmission information in which digital content produced based on a proper right and signature information relating to authentication of a creator of the digital content are transmitted. Information signal receiving means (49) for reproducing said digital content transmission information to obtain reproduction signature information relating to said signature information; and an unauthorized signature attached to digital content produced without a right. Signature information comparing means (47) for comparing an unauthorized signature information group in which information is accumulated and stored with the reproduced signature information to detect whether or not the reproduced signature information matches any of the illegal signature information groups; And when the reproduced signature information that matches the illegal signature information is detected by the signature information comparing means, the digital content A signal for stopping the reproduction of the contents transmission information, and when no match with the unauthorized signature information is detected, whether or not the reproduction signature information is signature information related to authentication of a creator of the digital content. Signature verification means (46) for verifying the signature of the signature information; and signature information recording means (additional storage of the reproduction signature information in the unauthorized signature information group when the validity of the reproduction signature information is not verified by the signature verification means). 51). A content information authenticating and reproducing apparatus comprising at least:

5) The unauthorized signature information group used for comparison with the reproduction signature information in the signature information comparing unit is the unauthorized signature information stored in the signature information recording unit, which is a removable portable storage medium. The content information authentication / reproduction device according to the item 3) or 4), wherein the content information authentication and reproduction is performed using a group.

6) The unauthorized signature information group used for comparison with the reproduction signature information in the signature information comparing means is the data of the unauthorized signature information group stored in a storage medium of a network server connected to a network. Get
It is characterized by using the obtained data 3)
Or 4) The content information authentication / reproduction device according to the item [4].

7) In the signature verification by the signature verification unit, the network server having the signature verification unit for verifying whether or not the reproduction signature information is the signature information related to the authentication of the creator of the digital content includes: The content information authenticating / reproducing apparatus according to 3) or 4), wherein the reproducing signature information is transmitted via a network, and the information is obtained by obtaining information on the result of the signature verification from the network server.

[0018] 8) The operation related to the suspension of the reproduction of the digital content in the signature verification means is performed by supplying reproduction impossible information indicating that the reproduction is not permitted to the decoder for decoding the digital content information and decoding. 3. The content information authenticating / reproducing apparatus according to the item 3) or 4), wherein the operation is an operation of stopping the operation.

9) The operation of the signature verification means for stopping reproduction of the digital content is performed even if the copy permission information attached to the digital content indicates that the copy is permitted. 3. The content information authenticating / reproducing apparatus according to the item 3) or 4), wherein the operation of stopping the supply of the digital content signal to another recording medium is performed.

10) The addition of the reproduction signature information to the group of unauthorized signature information in the signature information recording means is performed by additionally storing the information in a portable storage medium 3) or 4). The content information authenticating and reproducing apparatus described in the above.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a content information authenticating / reproducing method and a content information authenticating / reproducing apparatus according to the present invention will be described below. FIG.
FIG. 1 is a schematic block diagram of a content information authentication recording / reproduction system including a content information authentication / reproduction device equipped with the content information authentication / reproduction method, and its configuration and operation will be outlined.

The content information authentication recording / reproducing system shown in FIG.
4, a content information authentication recording device 10 including a signal recording unit 15, a digital content recording medium 20,
Display unit 61 and content information authenticating / reproducing device 40
It is composed of

The content information authenticating / reproducing apparatus 40 includes a recording signal reading section 41, a digital content memory 42, a decoder 44, a signature checking section 46, a signature information comparing section 47, a signature information recording section 51, and a history management section 52.
It is composed of

Next, the operation of the content information authentication recording / reproducing system thus configured will be outlined. First, for example, MPEG (moving picture experts group)
The digital content stored in the digital content unit 11 such as a bit stream compressed and encoded by the encoding method defined by the digital signature unit 1 is encoded by the signature creation unit 14 together with the signature information generated by the signature creation unit 14.
5, where the supplied signals are recorded on a digital content recording medium 20, such as a digital video tape.

The digital content recording medium 20 recorded in this manner is a digital content recording medium in which the digital content protected by the formal copyright is recorded together with the signature information on the copyright holder. The signature information of the digital content recording medium 20 in which the digital content 20 has been illegally copied and recorded is recorded as illegal signature information different from the signature information generated by encryption by the signature creation unit 14.

The digital content recording medium 20 recorded as described above is
0 reproduces and decrypts digital content and signature information. Next, the operation of the content information authenticating / reproducing apparatus 40 will be described.

First, the digital content recording medium 20
Is reproduced by the recording signal reading section 41, and the digital content obtained by the reproduction is supplied to the digital content memory 42, and the signature information is supplied to the signature checking section 46 and the signature information comparing section 47.

In the signature information comparing section 47, an incorrect signature information table recorded in advance in the signature information recording section 51 is compared with the supplied signature information, and signature information matching the incorrect signature information is detected. At this time, the reproduction disable information relating to the detection result is supplied to the decoder 44, and the decoder 44 stops the decoding operation of the digital content temporarily stored in the digital content memory 42.

On the other hand, if the signature information supplied to the signature information comparison unit 47 and the invalid signature information table recorded in the signature information recording unit 51 in advance do not detect a matching signature information, the signature The information comparison section 47 supplies a signature verification execution instruction signal to the signature verification section 46, and the signature verification section 46 verifies the validity of the supplied signature information by a cryptographic analysis method described later.

When the signature information is verified to be valid, reproduction permission / prohibition information for giving reproduction permission to the decoder 44 is supplied, and the decoder 44 supplies the content information temporarily stored in the digital content memory 42. For example, digital content that has been compression-encoded according to the MPEG standard is then decoded based on the MPEG standard, and the decoded video signal is supplied to a display unit 61 to display the content of the content. Is done.

The contents of the content verified as valid in this way are displayed. Conversely, if the signature verification unit 46 determines that the signature information is invalid,
The reproduction enable / disable information for stopping the decoding of the digital content is supplied to the decoder 44 to stop the decoding operation, and the determined signature determination information is supplied to the signature information comparing unit 47, and the signature information comparing unit 47 Supplies the signature information determined to be invalid to the signature information recording unit 51,
In the signature information recording unit 51, the supplied signature information is additionally recorded in an unauthorized signature information table.

The history management unit 52 connected to the signature information recording unit 51 records the recording date and time of the signature information additionally recorded in the unauthorized signature information table of the signature information recording unit 51 or the information in the recording order. When the recording amount in the signature information recording unit 51 approaches the predetermined recording capacity and the recording free space becomes smaller than the predetermined value at that time, for example, the oldest signature information is deleted in order. And a recording area is secured.

By using the recorded signature information table in this way, the processing time for signature verification performed by the signature verification unit 46 is reduced, and the unauthorized information recorded in the unauthorized signature information table is reduced. The reproduction of the digital content is immediately stopped by the reproduction of the digital content recording medium 20 and the display thereof.

In this way, the content information authenticating / reproducing apparatus 40 can reproduce the content content based on the digital content recorded on the digital content recording medium 20 and the unauthorized signature information reproduced and stored in the past. In addition to performing control on whether or not reproduction can be performed in a short time, when an unauthorized signature is detected, the signature information is added to an unauthorized signature information table, thereby further reducing the control time relating to the unauthorized signature information. Things.

The configuration and operation of the content information authenticating / reproducing apparatus 40 have been outlined above, and the configuration and operation will be further described. FIG. 2 shows the configuration of the content information authentication recording / playback system according to the first embodiment, and its operation will be described. The system shown in FIG. 2 is obtained by adding functions to the system shown in FIG. 1, and the added functions will be mainly described next.

The content information authentication recording / reproducing system shown in FIG. 1 comprises a content information authentication recording device 10a, a digital content recording medium 20, a display unit 61, and a content information authentication recording / reproducing device 40a. The content information authenticating / reproducing device 40a includes a copy control flag setting unit 12 and a hash function calculating unit 13 more than the information authenticating / recording device 10 of FIG.
Compared with 0, the hash function unit 43, the control unit 45, and the external output control unit 48 are included.

Next, the functions and operations of the content information authentication recording device 10a, the digital content recording medium 20, and the content information authentication reproduction device 40a thus configured will be further described.

First, the digital content stored in the digital content section 11 is not only a video signal compressed and encoded by MPEG or the like, but also an image signal, an encoded audio signal, and a video signal encoded by a method other than MPEG. A so-called digitized information signal such as a computer program is used.

The digitized information signal is supplied to the signal recording unit 15 and recorded on the digital content recording medium 20. The digital content recording medium 20 is not limited to a magnetic tape for a digital VTR.
A magnetic tape for recording digital data, such as a magnetic tape for a streamer, an optical disk such as a magneto-optical disk, a DVD, and a recording medium capable of recording digital signals such as a semiconductor memory are used.

The digital content recorded on the digital content recording medium 20 is used for the purpose of reproduction by the content information authenticating / reproducing apparatus 40a, and the content is supplied to another recording apparatus and copied. It is also managed with regard to reuse.

The control related to the reuse of the digital content is managed by a copy control flag set by a copy control flag setting unit 12, and the copy control flag is supplied to a signal recording unit 15. Is recorded on the digital content recording medium 20.

The copy control flag recorded on the digital content recording medium 20 is a flag indicating whether or not digital copying of the digital content recorded on the recording medium 20 to another recording medium is permitted. For example, CGMS (Copy Generation Ma
The copy control flag setting unit 12 sets permission information such as whether to permit a “child” having a copy generation of 1 or a “grandchild” having a copy generation of 2 by using the method of “Nagement System”.

The information thus set and recorded on the digital content recording medium includes signature information and signature setting flag information. Next, generation of the signature information and signature setting flag information will be described.

The signature information indicates the validity of the content recorded on the digital content recording medium 20, and a part of the information stored in the digital content section 11 is supplied to the hash function operation section 13, The hash function operation unit 13 performs an operation using a one-way function such as a hash function to obtain a message digest (hereinafter, referred to as an MD), and the obtained MD is supplied to the signature creation unit 14.

In the signature creation unit 14, the supplied MD
Is created using, for example, an RSA (public key cryptosystem) signature scheme developed by three professors of Rivest Shamir Adelman or a DSS (Digital Signature Standard) signature scheme. You.

In the signature creating section 14, a signature information flag indicating whether the signature information is recorded together with the signature information, for example, 1-bit binary data “0” indicates no signature information, and “1” indicates no signature information. Information indicating the presence of signature information is created, and the created signature information and signature information flag are supplied to the signal recording unit 15.

As described above, the digital content, the copy control flag, the signature information,
And signals such as a signature information flag are supplied, and the supplied signals are recorded on the digital content recording medium 20.

The digital content recording medium 20 thus recorded by the content information authentication recording device 10a is reproduced and decrypted by the content information authentication reproduction device 40a, and then reproduced by the content information authentication reproduction device 40a. The reproduction operation will be described.

First, the digital content recording medium 20
The digital signal recorded in the
And among the read signals, the signal relating to the digital content is
In addition, both the signature information and the signature information flag are supplied to both the signature verification unit 46 and the signature information comparison unit 47, and the copy control flag information is supplied to the external control output unit 48.

If the signature information flag of the supplied information is “0”, it indicates that no signature information is recorded on the digital content recording medium 20. The signature information does not need to be verified in the section 46, and the signature verification section 46 supplies reproduction enable / disable information for permitting reproduction to the decoder 44.

On the other hand, when the signature information flag is “1”, it indicates that the signature information is described.
The signature information comparison unit 47 to which the signature information flag is supplied.
Then, in the same manner as described with reference to FIG. 1 described above, the supplied signature information is compared with an unauthorized signature information table recorded in the signature information recording unit 51 in advance, and a matching signature information is detected. At this time, information that is not reproduced is supplied to the control unit 45.

If no matching signature information is detected, signature verification execution instruction information is supplied to the signature verification unit 46. Then, the signature verification unit 4 to which the instruction information is supplied.
In step 6, a predetermined content information portion of the digital content temporarily stored in the digital content section 42 is subjected to a hash function process by a hash function processing section and supplied as an MD (Message Digest) signal. The signature information to be verified is verified by the signature verification unit 46 using a public key managed by the copyright holder.

As a result of the verification operation, when the signature information is verified as valid, the digital content unit 4
The digital content information supplied to the
4 and decoded, and the decoded information signal is supplied to the display unit 61 and displayed, and a normal reproduction operation is performed.

Conversely, when the signature information is verified as invalid as a result of the verification operation, the digital content recording medium is determined to be invalid, and the signature verification unit 46 transmits to the control unit 45 the reproduction permission / prohibition information that is not reproduced. The digital content is supplied to the decoder 44 via the control unit 45, and the decoding operation of the digital content is stopped in the decoder 44, and the signature information verified as illegal is supplied to the signature information recording unit 51 and recorded there. It is additionally recorded in the invalid signature information table.

The writing of the unauthorized signature information additionally recorded in the signature information recording unit 51 is managed by the history management unit 52. If the area where the unauthorized signature information can be recorded is equal to or more than a predetermined amount, the unauthorized signature is stored therein. When information is recorded and the recording area is equal to or smaller than a predetermined amount, for example, the oldest unauthorized authentication information is erased, and newly supplied unauthorized authentication information is recorded.

Further, when such unauthorized signature information is detected, a message that "the digital content recording medium 20 is an unauthorized recording medium" is displayed on the display unit 61 to inform the user of the verification status. To

As described above, the digital content recorded on the digital content recording medium 20 is subjected to verification of the signature information and the signature information flag.
Only when the signature information is not recorded and when the verification of the signature information is normally performed, the signal decoded from the content information authenticating / reproducing device 40a is supplied to the display unit 61 and displayed.

The content information authenticating / reproducing apparatus 40a supplies the signal of the digital content recording medium 20 read by the recording signal reading section 41 to another recording apparatus via the external output control section 48. In addition, a function for making a copy record is provided.

The external output control section 48 is supplied with a copy control flag signal read from the digital content recording medium 20, and performs other operations according to the content of the copy control flag signal and the result of verification of the signature information. Supply or non-supply of the signal supplied to the recording apparatus is controlled.

That is, the digital content recording medium 20
The digital content, the copy control flag, and the signature information that are recorded in the storage device are supplied to another recording device and digital copying is performed only when the copy control flag has information on copy permission. The digital content signal and accompanying information are supplied to another recording device.

When the above-mentioned illegal signature information is detected, the recording signal reading section 41 sends a copy control flag for permitting copying to the external output control section 48.
Even if the content can be digitally copied or copied only once, the copy control supplied from the recording signal reading unit 41 so that the information relating to the digital content is not supplied to the external recording device. The flag is changed to a flag relating to copy prohibition.

Next, the copy control thus performed will be described. FIG. 3 is a flowchart illustrating a signal recording process related to copy control, which will be described.

First, at step 1 (S1), it is checked whether or not the copy control flag has been set by the copy control flag setting section 12, and if not, the signature setting step of step 3 (S3) is performed. If the copy control flag is set in step S1, the copy control flag is set in step 2 (S2), and then the process proceeds to the signature setting step in step S3.

In step S3, after the signature is set in the signature creation unit 14, the process proceeds to step 4 for recording the content, signature information, signature information flag, and copy control flag. In step 4, the signal recording unit 15 Thereby, the recording operation of those signals on the digital content recording medium 20 is performed.

Next, the operation of reading the recorded digitally recorded content will be described. FIG. 4 is a flowchart illustrating a signal reproduction process related to the reading control of the digital recording content recording medium, which will be described.

First, a copy control flag to be recorded is detected in step 11, and it is checked in step 12 whether or not copying is permitted by the copy control flag. The contents of the flag are updated, a signal for signal recording is supplied from the external output control unit 48 to the external recording device, and the process proceeds to the next step 15.

If the result of the determination in S12 is that copying is not permitted, output to the external recording device is prohibited in step 14, and the process proceeds to step 15 for detecting a signature information flag, where the signature recorded on the recording medium 20 is recorded. An information flag is detected.

Then, in step 16, it is checked whether or not the detected signature information flag is "1". If not, the processing relating to the read control of the recorded content recording medium is terminated, and the digital content is read. When the reproducing operation of the recording medium 20 is started and the detected signature information flag is “1”, step 1 is executed.
7, the signature information is read.

The signature information read in step 17 is compared in step 18 with the stored unauthorized signature table to determine whether or not the signature information is already stored. If there is any unauthorized signature information (No), the process proceeds to step 22. When the reproduction of the content is stopped and there is no matching unauthorized signature information (Yes
), The signature information verification operation in step 19 is performed.

Based on the result of the verification performed in the step 19, it is determined whether or not the content is valid by the signature verification in the step 20, and if the content is valid, the process related to the reading control of the content recording medium is terminated and the digital When the reproduction operation of the content recording medium 20 is started and when it is determined that the content is not valid, the unauthorized signature information is supplied to the signature information recording unit 51 in step 21 and is additionally recorded in the unauthorized signature memory table. The reproduction of the content storage medium is stopped.

As described above, based on the copy control flag, the signature information, and the signature information flag information recorded on the digital content recording medium 20, the reproduction and decoding operations of the recorded content and the external operation of the content are performed. A control operation for copying to the connected device is performed.

The unauthorized signature information is compared with an unauthorized signature information list recorded in a signature information recording unit in advance, so that the unauthorized signature information is subjected to a signature information verification operation whose operation is complicated. It can be easily obtained without using.

Therefore, the information relating to the unauthorized signature table recorded in the signature information recording section 51 and the history management section 52 is recorded on a removable storage medium such as a floppy disk or an IC memory element. By moving the content stored in the storage medium along with the storage medium and copying it to the signature information recording unit of the content information authentication / reproduction device different from the device 40a, the different content information authentication / reproduction device stores the content in the unauthorized signature table. The operation of detecting an unauthorized signature is easily performed based on the obtained signature information.

Such an operation of detecting an unauthorized signature is performed when the signature information flag is read out as a signature information flag indicating that "signature information exists". Therefore, if the information of “there is signature information” recorded in the signature information flag is falsified and supplied as “there is no signature information”, an unauthorized signature detection operation is not performed.

Therefore, the recording of the signature information flag on the digital content recording medium is not a simple recording method such as simply recording it in the header area of the content information, but the signature flag information is embedded in the content information. Must be recorded.

That is, the signature information flag information relating to the presence / absence of the recorded signature information is, for example, embedded as watermark information in the content. In the case where the content is changed without the signature information, there is a method of preventing the content itself from being broken and the content from being normally decrypted and displayed.

In order to protect such content, the content information authentication recording device encrypts and records at least a part of the content, and the content information authentication reproduction device decrypts the encrypted content. And reproduction.

In other words, a configuration is employed in which a signature information flag indicating whether or not signature information is present is embedded in such encrypted content so that the encrypted signal is not decrypted when the information flag is falsified. It is easy.

In the above, the authentication of the digital content recorded on the digital content recording medium and the decoding operation of the content information by the content information authentication recording apparatus in the first embodiment have been described. The digital content is recorded on the recording medium. In addition to being conveyed, a similar content information authentication transmission / reception system can be configured for digital content information that is directly transmitted using a communication path or a broadcast transmission path.

FIG. 5 shows the configuration of the content information authentication transmission / playback system. In the content information authentication transmission device 10b according to the second embodiment shown in FIG. 10, the signal recording unit 15 is provided in the transmission device 16 and the digital content recording medium 20 is provided in the transmission path 30 in comparison with the content information authentication recording device 10a described above. Is different.

Then, the content information authenticating and reproducing apparatus 40
b is configured such that the recording signal reading unit 41 is configured as a receiving device 49 for the content information authenticating / reproducing device 40a, but the other configuration is the same. The difference is that digital content is distributed using a medium, and the other operations are the same as those of the content information authentication recording apparatus according to the first embodiment.

As described above, the digital content authentication and the content information decoding operation in the content information authentication recording / reproducing system shown in the first embodiment are performed in the content information authentication transmission / reproduction system shown in the second embodiment. Is performed similarly.

In the second embodiment, the transmission path 30 is used instead of the digital content recording medium 20, but the transmission path is used for transmitting an unauthorized signature information table recorded in the signature information recording section. You can also.

In FIG. 6, a storage medium for storing the unauthorized signature information table is provided in the network server 50, and the content information authenticating / reproducing apparatus in a case where the unauthorized signature information is transmitted via a transmission network or obtained via the network. The configuration of 40c will be shown and described.

The content information authenticating and reproducing apparatus 4 shown in FIG.
0c has no signature information recording unit 51 and no history management unit 52 as compared with the configuration of the content information authentication / reproduction device 40b in FIG. 5 described above, and the signature verification unit 46 is connected to the network server 5 via the network interfaces 31 and 32.
0, the signature information recording unit 51 and the history management unit 52 are connected.

The verification of the unauthorized signature information in the signature verification unit connected in this manner is performed in the same manner as in the above-described signature verification unit 46 shown in FIG. 2, and the verification operation recognizes that the content and the medium are invalid. In this case, the reproduction permission / non-permission information in the content information authenticating / reproducing apparatus in which the work has been performed includes an instruction signal indicating that reproduction is not permitted or reproduction is stopped.
And the verified unauthorized signature information is supplied to the signature information recording unit 51 of the network server 50 via the network interfaces 31 and 32.

The unauthorized signature information is shared by a plurality of content information authenticating / reproducing devices connected to the network server 50 via a network, and the unauthorized signature information list is shared by a plurality of content information authenticating / reproducing devices. Each of the unauthorized signature information verified and used by each content information authenticating and reproducing device is supplied to the network server 50.

The network server 50 is supplied with a large amount of unauthorized signature information detected by a plurality of content information authenticating / reproducing devices, and a database relating to the unauthorized signature information is constructed in a short period of time. Verification work by the authentication reproducing device is reduced.

The capacity of the signature information recording unit of the network server that stores the database is set large, but the unauthorized signature information supplied to the signature information recording unit is made by the history management unit 52, If there is a free area that can be recorded in the unauthorized signature information recording area of the recording unit 51, the unauthorized signature information is recorded in the signature information recording unit. If the recordable area is insufficient, for example, The old fraudulent authentication information is deleted, and the newly supplied fraudulent authentication information is recorded.

In the case of the content information authenticating / reproducing apparatus in the first embodiment, the unauthorized authentication information recorded in this manner is stored in an unauthorized signature information list via a floppy disk or an IC memory element. Although the data is shared between the authenticating and reproducing apparatuses, the sharing of the unauthorized signature data by the network connection requires updating the data of the newly verified unauthorized signature data in real time and performing the operation of exchanging the storage medium. Therefore, the operation for verifying the signature data in each content information authenticating / reproducing apparatus can be reduced.

The third embodiment in which the network server 50 has the signature information recording unit 51 and shares unauthorized signature data has been described above. Next, an example will be described in which the network server is provided with a signature verification unit. .

FIG. 7 shows the configuration of a content information authenticating / reproducing apparatus according to the fourth embodiment in the case where a signature verification section is provided in the network server, and the operation thereof will be described.

That is, the content information authenticating / reproducing apparatus 40d shown in the figure is different from the content information authenticating / reproducing apparatus 40c according to the third embodiment shown in FIG. Although there is no circuit unit of the verification unit 46 and the signature information comparison unit 47, they are the hash function unit 43, the signature verification unit 46, and the signature information comparison unit in the network server 50a via the network interface 31a and the network interface 31b. It is different in that it is configured to be connected to the unit 47.

The operation of the content information authenticating / reproducing apparatus 40d configured as described above is different from the operation of the content information authenticating / reproducing apparatus 40c in that when an operation related to signature verification is required, the operation is transmitted to the network server 50a via the network. The server 50a requests a verification operation, and in accordance with the result obtained by the verification operation, reproduction enable / disable information on the content information authenticating / reproducing device 40d is supplied to the control unit 45 via the network, The unauthorized signature information is recorded in the signature information recording unit 51 in the same manner as described above.

That is, the content information authenticating and reproducing apparatus 40d
The network server 50a supplies the signature information, the signature information flag, and a part of the information of the content necessary for creating the message digest of the digital content to the network server 50a via the network interface 31a. Then, the information signal supplied through the network interface 32a is obtained, and the signature is authenticated.

In this manner, the signal for the signature authentication work performed via the network and the information on whether or not it can be reproduced are transmitted through the network since there is a possibility that the signal is falsified by another computer connected to the network. It is desirable that the signal to be transmitted be sufficiently encrypted.

Then, in the network server 50a,
Sufficient to prevent unauthorized signature data recorded in the signature information recording section from being erased by external access, or from being tampered with, such as legitimate signature information being recorded as unauthorized signature information. Although it is desirable to configure the system with an encryption system protected by the above, it is necessary to maintain and manage the stored data by periodically re-verifying the recorded unauthorized signature data.

As described above, according to the first to fourth embodiments, the recording / reproducing method, the transmission / reception method for verifying the signature information at high speed and easily by using the stored unauthorized signature data, and the configuration of the apparatus equipped with them. , And their operation.

When reproducing or receiving the digital content information to which the signature information and the signature flag information are added by the recording and transmission device, the digital content and the signature information transmitted by the recording medium or the transmission medium are authenticated. And if it is verified that the content is unauthorized content and media, stop the playback and
When the medium having the unauthorized signature information is to be reproduced again, the reproduction of the content can be prohibited or stopped without performing the authentication processing, thereby shortening the processing time and simplifying the processing. it can.

Since the unauthorized signature information is recorded on a removable recording medium or a memory element, the unauthorized signature information recording medium or the memory element is duplicated and reproduced. By supplying the unauthorized signature information recording medium to the apparatus or the receiving apparatus, the work for signature authentication can be speeded up and simplified by a plurality of apparatuses.

When a plurality of reproducing apparatuses or receiving apparatuses are connected by a network and the unauthorized signature information is supplied via the network, one of the plurality of apparatuses is required.
Since the unauthorized signature information verified by the two devices can be shared at the same time, a reproducing device or a receiving device that operates by verifying the signature information more easily can be configured.

Further, the unauthorized signature information is verified and obtained by the network server connected to the network, and the obtained unauthorized signature information is recorded. An authentication processing speed capable of reproducing or receiving digital content based on signature information verified by a network server having a high calculation function even if the apparatus does not have a signature information verification function. , And a low-cost content information authentication / reproduction apparatus can be configured.

[0103]

According to the first aspect of the present invention, a digital content recording medium in which digital content produced based on a proper right is added with signature information relating to the production of the digital content and recorded is reproduced. In doing so, the playback signature information obtained by playback is compared with an unauthorized signature information table that stores a plurality of unauthorized signature information attached to digital content created based on an unjust right that has been stored in advance, and the unauthorized signature information is compared. If the digital signature is detected and the unauthorized signature information is detected, the reproduction of the digital content recording medium is stopped. If the unauthorized signature information is not detected, the signature verification related to the verification of the validity of the reproduced signature information is performed and the validity is verified. When not performed, the reproduction signature information is added to the unauthorized signature information table and stored, so that complicated arithmetic processing is required. It is possible to reduce the frequency of performing the testimony process, there is an effect that can provide authentication reproducing method content information reduces an authentication process time is possible the processing process according to the authentication process in a simple manner.

According to the second aspect of the present invention, digital content created based on a right is added with signature information relating to the creation of the digital content, and the transmitted digital content information is reproduced. At this time, the reproduction signature information obtained by reproduction is compared with an unauthorized signature information table that stores a plurality of unauthorized signature information attached to digital contents created based on an unjustified right that is stored in advance and detects the unauthorized signature information. However, when the unauthorized signature information is detected, the reproduction of the digital content recording medium is stopped. When the unauthorized signature information is not detected, the signature verification related to the verification of the validity of the reproduced signature information is performed, and the validity is not verified. In some cases, the reproduction signature information is added to the unauthorized signature information table and stored. It is possible to reduce the frequency of performing the testimony process, there is an effect of providing content information authentication reproducing method with reduced authentication processing time it is possible to process according to the authentication process in a simple manner.

According to the third aspect of the present invention, a digital content recording medium in which digital content produced based on a proper right is added with signature information relating to the production of the digital content and recorded is reproduced. In doing so, the playback signature information obtained by playback is compared with an unauthorized signature information table that stores a plurality of unauthorized signature information attached to digital content created based on an unjust right that has been stored in advance, and the unauthorized signature information is compared. If the digital signature is detected and the unauthorized signature information is detected, the reproduction of the digital content recording medium is stopped. If the unauthorized signature information is not detected, the signature verification related to the verification of the validity of the reproduced signature information is performed and the validity is verified. Otherwise, the playback signature information is added to the unauthorized signature information table and stored.
The frequency of performing authentication processing by complicated arithmetic processing can be reduced, the processing means for the authentication processing can be simply configured, and the configuration of the content information authenticating / reproducing apparatus in which the authentication processing time is reduced can be provided.

According to the fourth aspect of the present invention, digital content created based on a right is added with signature information relating to the creation of the digital content, and the transmitted digital content information is reproduced. At this time, the reproduction signature information obtained by reproduction is compared with an unauthorized signature information table that stores a plurality of unauthorized signature information attached to digital contents created based on an unjustified right that is stored in advance and detects the unauthorized signature information. However, when the unauthorized signature information is detected, the reproduction of the digital content recording medium is stopped. When the unauthorized signature information is not detected, the signature verification related to the verification of the validity of the reproduced signature information is performed, and the validity is not verified. In some cases, the reproduction signature information is added to the unauthorized signature information table and stored. It is possible to reduce the frequency of performing the testimony process, there is an effect of providing a structure of reducing the content information authentication reproducing apparatus authentication processing time it is possible to configure the processing means according to the authentication process in a simple manner.

According to the fifth aspect of the present invention, in addition to the effects of the third and fourth aspects, in particular, signature comparison is performed using an unauthorized signature information table stored in a removable portable storage medium. Thus, there is an effect that a processing step related to the authentication processing can be further simplified and an authentication reproduction method of the content information in which the authentication processing time is reduced can be provided.

According to the sixth aspect of the invention, in addition to the effects of the third and fourth aspects, in particular, in the signature comparison, a storage medium of a network server connected to a network is accessed and stored in the storage medium. Since the authentication process is performed using the data of the unauthorized signature information table, it is possible to provide a method for authenticating and reproducing content information in which the processing steps relating to the authentication processing can be further simplified and the authentication processing time is reduced.

According to the seventh aspect of the invention, in addition to the effects of the third and fourth aspects, in particular, the signature verification is performed by a network server connected to the network and having a function of verifying the validity of the reproduction signature information. Since the reproduction signature information is transmitted, and the signature verification information relating to the result of verifying the validity of the reproduction signature information is obtained from the network server via the network, the processing steps relating to the authentication processing can be further simplified and There is an effect that an authentication reproduction method of content information in which the authentication processing time is reduced can be provided.

According to the eighth aspect of the present invention, in addition to the effects of the third and fourth aspects, in particular, the operation relating to the suspension of the reproduction of the digital content is a decoding operation for decoding the compression-encoded digital content information. Since the reproduction disable information indicating that the reproduction is not permitted is supplied to the device, the digital content information that is erroneously decoded due to the delay time related to the processing step related to the authentication processing is reproduced. There is an effect that a method of authenticating and reproducing content information can be provided in which a malfunction such as erroneous operation is prevented.

According to the ninth aspect of the present invention, in addition to the effects of the third and fourth aspects, in particular, the operation relating to the stop of the reproduction of the recording medium is performed in the digital content recording medium. Even if copy permission information permitting copying to another recording medium is recorded, the operation for stopping the signal supply for the copy is simultaneously performed to prevent a malfunction related to the copy permission. There is an effect that a method of authenticating and reproducing content information can be provided.

According to the tenth aspect of the present invention, in addition to the effects of the third and fourth aspects, in particular, when the reproduction signature information is added to the unauthorized signature information table, it is additionally stored in a portable storage medium. Therefore, the stored unauthorized signature information table can be used for the authentication / reproduction method of other content information, so that the processing steps of the authentication processing of the content information authentication / reproduction device equipped with the authentication method can be simplified. In addition, there is an effect that an authentication reproduction method of content information in which the authentication processing time is reduced can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a configuration of a content information authentication recording / reproduction system according to a content information authentication / reproduction apparatus of the present invention.

FIG. 2 is a diagram showing a configuration of a content information authentication recording / playback system according to a first example of the present invention.

FIG. 3 is a flowchart illustrating an operation of a recording signal according to the content information authentication recording apparatus according to the embodiment of the present invention.

FIG. 4 is a flowchart illustrating an operation of a reproduction signal according to the content information authentication / reproduction apparatus according to the embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of a content information authentication recording / playback system according to a second example of the present invention.

FIG. 6 is a diagram showing a configuration of a content information authentication / reproduction device according to a third embodiment of the present invention.

FIG. 7 is a diagram showing a configuration of a content information authentication / reproduction device according to a fourth embodiment of the present invention.

[Explanation of symbols]

10, 10a content information authentication recording device 10b content information authentication transmission device 11 digital content section 12 copy control flag setting section 13 hash function operation section 14 signature creation section 16 transmission apparatus 20 digital content recording medium 30 transmission paths 31, 31a, 32, 32a Network Interface 40, 40a, 40b, 40c, 40d Content Information Authentication / Reproduction Device 41 Recorded Signal Readout Unit 42 Digital Content Memory 43 Hash Function Unit 44 Decoder 45 Control Unit 46 Signature Inspection Unit 47 Signature Information Comparison Unit 48 External Output Control Unit 49 Receiving device 50, 50a Network server 51 Signature information recording unit 52 History management unit 61 Display unit

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Claims (10)

[Claims] 1. A method for authenticating and reproducing content information for reproducing only a digital content recording medium in which digital content produced based on a proper right and signature information relating to authentication of a creator of the digital content are recorded. A first step of reproducing the digital content recording medium to obtain reproduction signature information related to the signature information; and accumulating unauthorized signature information attached to digital content produced without a right. A second step of comparing the stored unauthorized signature information group with the playback signature information to detect whether or not the playback signature information matches any of the unauthorized signature information groups; If the reproduction signature information matching the unauthorized signature information is detected by the step, the reproduction of the digital content recording medium is stopped. A third signal for verifying whether or not the reproduction signature information is signature information related to authentication of a creator of the digital content when a match with the unauthorized signature information is not detected. And a fourth step of, when the validity of the reproduction signature information is not verified by the signature verification, additionally storing the reproduction signature information in the unauthorized signature information group. Authentication reproduction method of information. 2. An authenticated reproduction of content information for reproducing only digital content transmission information in which digital content produced based on a proper right and signature information relating to authentication of a creator of the digital content are transmitted. A first step of reproducing the digital content transmission information to obtain reproduction signature information relating to the signature information; and a method of transmitting unauthorized digital signature information attached to digital content produced without a right. A second step of comparing the cumulatively stored unauthorized signature information group with the playback signature information to detect whether the playback signature information matches any of the unauthorized signature information groups; When the reproduction signature information that matches the unauthorized signature information is detected by the step of, the reproduction of the digital content transmission information is stopped. A third signal for verifying whether or not the reproduction signature information is signature information relating to authentication of the creator of the digital content when no match with the unauthorized signature information is detected. And a fourth step of, when the validity of the reproduction signature information is not verified by the signature verification, additionally storing the reproduction signature information in the unauthorized signature information group. Authentication reproduction method of information. 3. A content information authenticating / reproducing apparatus for reproducing only a digital content recording medium which records digital content produced based on a proper right and signature information relating to authentication of a creator of the digital content. Recording signal reading means for reproducing the digital content recording medium to obtain reproduction signature information relating to the signature information; and accumulatively storing unauthorized signature information attached to digital content produced without a right. Signature information comparing means for comparing the obtained unauthorized signature information group with the reproduced signature information to detect whether the reproduced signature information matches any of the illegal signature information groups, and the signature information comparing means When the reproduction signature information that matches the unauthorized signature information is detected by the And a signature verification is performed to determine whether or not the reproduction signature information is signature information related to the authentication of the creator of the digital content when no match with the unauthorized signature information is detected. A signature verification unit; and a signature information recording unit configured to additionally store, when the validity of the reproduction signature information is not verified by the signature verification unit, in the unauthorized signature information group. A content information authentication / reproduction apparatus characterized by the above-mentioned. 4. A content information authenticating / reproducing apparatus for reproducing only digital content transmission information in which digital content produced based on a proper right and signature information relating to authentication of a creator of the digital content are transmitted. An information signal receiving means for reproducing the digital content transmission information to obtain reproduction signature information related to the signature information, and accumulating unauthorized signature information attached to digital content produced without a right. Signature information comparing means for comparing the stored unauthorized signature information group with the playback signature information to detect whether the playback signature information matches any of the unauthorized signature information groups, and comparing the signature information; Means for reproducing the digital content transmission information when the reproduction signature information matching the unauthorized signature information is detected by the means. A signature for supplying a signal for canceling, and for verifying whether or not the reproduction signature information is signature information relating to authentication of a creator of the digital content when no match with the unauthorized signature information is detected. Verification means; and signature information recording means for additionally storing the reproduction signature information in the unauthorized signature information group when the validity of the reproduction signature information is not verified by the signature verification means. A content information authenticating / reproducing apparatus characterized by the above-mentioned. 5. The unauthorized signature information group used by the signature information comparing means for comparison with the reproduced signature information is the unauthorized signature information stored in the signature information recording means, which is a removable portable storage medium. 5. The content information authentication / reproduction device according to claim 3, wherein the content information authentication / reproduction is performed using a group. 6. The unauthorized signature information group used for comparison with the reproduction signature information in the signature information comparing means is the data of the unauthorized signature information group stored in a storage medium of a network server connected to a network. 5. The content information authenticating / reproducing apparatus according to claim 3, wherein the content information authentication / reproduction is performed using the obtained data. 7. The method according to claim 1, wherein the signature verification is performed by a network server having signature verification means for verifying whether the reproduction signature information is signature information relating to authentication of a creator of the digital content. 5. The content information authenticating / reproducing apparatus according to claim 3, wherein the reproducing signature information is transmitted via a network, and the information is obtained by obtaining information relating to the result of the signature verification from the network server. 8. The operation of the signature verification means for stopping reproduction of the digital content is performed by supplying reproduction disable information indicating that reproduction is not permitted to a decoder for decoding the digital content information. 5. The content information authenticating / reproducing apparatus according to claim 3, wherein the operation is an operation of stopping the operation. 9. The operation of the digital signature verification means for stopping reproduction of the digital content, even if the copy permission information attached to the digital content is copy permitted, 5. The content information authenticating / reproducing apparatus according to claim 3, wherein the operation of stopping the supply of the digital content signal to another recording medium is performed. 10. An apparatus according to claim 3, wherein said signature information recording means adds said reproduction signature information to said unauthorized signature information group by additionally storing it in a portable storage medium. Content information authentication playback device.