RU2273893C2 - Device and method for recording/reproducing information, carrier of recorded information and means for servicing program for recording/reproducing information - Google Patents

Abstract

FIELD: method and device for recording and reproducing information.

SUBSTANCE: block key for encoding block data is generated with utilization of input time mark, connected to each packet, included in transport stream in accordance to packet input time. Input time mark contains random data, depending on input time, and thus it is possible to generate unique block key, which increases data protection from encryption analysis. Block key is generated on basis of combination of mark of input time with key, unique for device, information carrier or the like, such as main key, unique disk key, unique title key or the like. Because for generation of block key input time mark is utilized, it is possible not to assign zone on data carrier for storing encoding key for each block.

EFFECT: increased data protection quality.

7 cl, 41 dwg

Description

FIELD OF THE INVENTION

The present invention relates generally to an information recording apparatus, an information reproducing apparatus, an information recording method, an information reproducing method, an information storage medium and a program maintenance means, and in particular, to an information recording apparatus, an information reproducing apparatus, an information recording method, an information reproducing method, a storage medium and a program execution means capable of preventing illegal copying and recording of data on a storage medium onto which it is possible to store ik- and from which data can be reproduced.

State of the art

In connection with recent advances in the development of digital signal processing technology, digital recording / reproducing devices and storage media are of primary importance. Using such a digital recording / reproducing device and a storage medium, it is possible to re-record and reproduce, for example, images or sound without compromising their quality. Since digital data can be copied many times without degrading the quality of the image and sound, media with illegally recorded digital data upon entering the market deprives the owners of copyrights of various contents such as music, movies, etc., or the legal distributors of the content that they would receive if it was impossible to illegally copy. To prevent such illegal copying of digital data, various systems for preventing illegal copying have recently been introduced into digital recording / reproducing devices and storage media.

As an example of the above systems for preventing illegal copying in an MD (mini-disk) drive (MD is a trademark), SCMS (Copy Sequence Management System) is used. SCMS operates so that on the data playback device side, audio data is output together with the SCMS signal from the digital interface (DIF), while on the data recording device side, audio data recording from the data playback device side is controlled based on the SCMS signal from the playback device side data, which prevents illegal copying of audio data.

In particular, this SCMS signal indicates that the audio data is data that can be freely copied, which can be freely copied many times, data for one-time copy, which can be copied only once, or data that is forbidden to be copied, copying of which is prohibited. On the data recorder side, when receiving audio data from the digital interface, a SCMS signal is detected transmitted along with the audio data. If the SCMS signal indicates that the audio data is free for data copying, then the audio data with the SCMS signal is recorded on the mini-disk. If the SCMS signal indicates that the audio data is data allowed for one copy, the audio data is converted to data prohibited for copying and the SCMS signal along with the audio data is recorded on the mini-disk. In addition, if the SCMS signal indicates that audio data is prohibited for copying data, then audio data is not recorded on the mini-disc. The SCMS signal helps prevent illegal copying of copyrighted audio data to the mini-disk drive unit.

However, SCMS is only effective when the data recorder itself is configured to control recording of audio data from the side of the data reproducing device based on the SCMS signal. Therefore, it is difficult for an SCMS system to support a mini-disk drive that is configured without SCMS control. For SCMS applications, for example, a DVD player uses a content scrambling system to prevent illegal copying of copyrighted data.

The content scrambling system is configured such that encrypted image data, audio data, and the like. are written to a DVD-ROM (read-only memory) and each licensed DVD player is given an encryption key to decrypt the encrypted data. A license is issued to a DVD playback device in accordance with predetermined rules of operation, excluding illegal copying, etc. Therefore, when using an encryption key, a licensed DVD player can decrypt the encrypted data recorded in the DVD-ROM to play video and audio data from the DVD-ROM.

On the other hand, an unlicensed DVD player cannot decrypt the encrypted data recorded in the DVD-ROM because it does not have an encryption key for the encrypted data. Thus, the content scrambling system does not allow a DVD player that does not meet the licensing conditions to play a DVD-ROM in which digital data is recorded in order to prevent illegal copying.

However, the content scrambling system used in the DVD-ROM is directed to a storage medium onto which the user cannot record data (hereinafter referred to as ROM storage medium), but not to any storage medium to which the user can record data (hereinafter referred to as RAM carrier).

Thus, copying all the encrypted data recorded on the ROM medium, as it is, into the RAM medium creates a so-called pirated data publication that can be played by a licensed DVD player.

To solve this problem, the applicant of the present invention proposed, as disclosed in Japanese Patent Application Laid-Open No. 224461 of 1999 (Japanese Patent Application No. 25310 of 1998), a method in which information for identifying each information carrier (hereinafter referred to as carrier identification information) is recorded with other data on the storage medium to provide access to the identification information of the storage medium in the storage medium only when the playback device that is to play the storage medium is licensed For media identification information.

According to this method, the data in the storage medium is encrypted with a private key (master key) obtained by licensing the media identification information, so that any unlicensed reproducing device cannot receive any meaningful data, even if it can read the encrypted data. It should be noted that the playback device licensed for media identification information has an operation mode restricting illegal copying.

A licensed playback device may access media identification information. Media identification information is unique to each information carrier. Even if an unlicensed playback device can copy all encrypted data recorded on such a storage medium to a new storage medium, data recorded in this way on a new storage medium cannot be correctly decrypted by an unlicensed playback device, as well as a licensed playback device. Thus, it is essentially possible to prevent illegal copying of data.

It must be recalled that the method disclosed in Japanese Patent Application Laid-Open No. 224461 of 1999 (Japanese Patent Application No. 25310 of 1998) uses a sector key unique to each sector of the disk to encrypt content data such as image, sound, program and etc. to be written to disk.

The above method is intended to solve the problem that if a large amount of data is encrypted with one encryption key, the encryption key can be opened using differential or linear cryptanalysis with a combination of encrypted text recorded on the information medium and open or decrypted data, obtained by an attacker by any means. In the method disclosed in said uploaded application of the applicant of the present invention, a different encryption key is assigned to each sector of a given size, so that only a limited amount of data can be processed by one encryption key, which makes it difficult to disclose the encryption key. In addition, the method allows to minimize the amount of data that can be decrypted if the encryption key is opened.

However, in the example described in said Japanese laid-out application, an encryption key (sector key) for each sector used to decrypt the contents is additionally encrypted with a higher order key and stored in the header sector of the information medium. Thus, the storage medium should provide a zone wide enough to store the sector key in the header sector, and access to the header sector for recording (for writing) or reading (for playback) of the encrypted encryption key should be provided for recording or reproducing content.

SUMMARY OF THE INVENTION

In accordance with this aim of the present invention is to remedy the above-mentioned disadvantages of the prior art by creating an information recording device, an information reproducing device, an information recording method, an information reproducing method, a recorded information medium and a program maintenance means in which block data can be encrypted with various encryption keys, accordingly, to improve protection against cryptographic data analysis without the need for any recording area For encryption keys on the storage medium or on the disk, namely, without narrowing the existing data area in the storage medium.

In particular, the present invention aims to provide an information recording device, an information reproducing device, an information recording method, an information reproducing method, an information storage medium and program execution means in which an entry time mark (ATS) formed in the form of random data corresponding to each entry time The packet included in the data transport stream is used to generate a block key for encrypting block data, thereby enhancing protection against cr ptograficheskogo data analysis, and in which the arrival time stamp is used to generate a block key for each block in the carrier without providing additional information area for storing the encryption key for each block, which ensures efficient use of the main data area in the recording medium.

According to a first aspect of the present invention, an information recording device for recording information on an information medium can be created, the device comprising: transport stream processing means for attaching an entry time stamp (ATS) to each of the discrete transport packets included in the transport stream; and cryptographic means for generating a block key for encrypting block data including more than one transport packet, each of which has an attached entry time stamp, from the starting number of the block, which is additional information unique to the block data, and includes an entry time stamp, and encryption each data block using the thus generated block key; however, data encrypted using cryptographic means are recorded on the storage medium.

In the above information recording apparatus according to the present invention, the cryptographic means generates a block key for encrypting the block data from the initial number of the block, which is additional information unique to the block data, and includes an entry time stamp attached to the first packet of the plurality of transport packets, included in the block data.

In addition, in the specified information recording device according to this invention, the cryptographic means generates a unique title key from the main key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to the data, to be recorded on the storage medium, and generates a block key from a unique title key and the starting number of the block.

In addition, in the specified information recording device according to this invention, the cryptographic means generates a disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to the data to be recorded on the information medium, and stores them on the information medium .

In addition, in the specified information recording device according to the present invention, the initial block number contains copy control information in addition to the entry time stamp.

In addition, in the information recording apparatus according to this invention, the cryptographic means encrypts only the data included in the block data with the block key and excludes data in the initial zone including the starting number of the block.

In addition, in the specified information recording device according to this invention, the cryptographic means generates a unique title key from the main key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to the data, to be recorded on the storage medium, uses the unique title key generated in this way as a key for the encryption function, substitutes the initial number the block into the encryption function and returns the result of the substitution as a block key.

In addition, in the specified information recording device according to this invention, the cryptographic means generates a unique title key from the main key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to the data to be recorded on the storage medium, substitutes the unique title key generated in this way and the initial block number in a one-way function and gives This is the result of substituting as a block key.

In addition, in the specified information recording device according to this invention, the cryptographic means generates a unique device key either from the key of the large integrated circuit stored in the large integrated circuit contained in the cryptographic means or from the key of the device stored in the information recording device, or from the media key stored in the storage medium, or from the drive key stored in the drive unit for the storage medium, or based on a combination of these keys, and generates a block spanner to the encryption unit from a unique device key generated in this way and a seed block.

In addition, in the specified information recording device according to this invention, the cryptographic means encrypts the block data with the block key in accordance with the DES algorithm (data encryption standard).

In addition, said information recording device comprises interface means for receiving information to be recorded on the information medium and for identifying copy control information attached to each of the packets included in the transport stream to determine, based on the copy control information, whether or not recording is allowed storage medium.

In addition, said information recording apparatus comprises interface means for receiving information to be recorded on the information medium and identifying a two-bit encryption mode indicator (EMI) as copy control information for determining, based on the EMI, whether or not recording is allowed on the information medium.

According to a second aspect of the present invention, an information reproducing apparatus for reverse reproducing information from an information medium can be created, the device comprising: cryptographic means for decrypting encrypted data recorded on the information medium by generating a block key for decrypting encrypted data in block data having a label entry time, attached to each of the many transport packets, from the initial number of the block, which is an additional information that is unique to block data and includes a timestamp of the entry and decryption of each data block by the thus generated block key; and transport stream processing means for controlling data output based on an entry time stamp attached to each of a plurality of transport packets included in the block data decrypted by cryptographic means.

In the above information reproducing apparatus according to the present invention, the cryptographic means generates a block key for decrypting the block data from the initial number of the block, which is additional information unique to the block data, and includes an entry time stamp attached to the first packet of the plurality of transport packets, included in the block data.

In addition, in the above information reproducing apparatus according to the present invention, the cryptographic means generates a unique title key from a master key stored in the information reproducing apparatus, a disk identifier, which is an identifier of an information medium unique to an information medium, and a title key unique to data to be recorded on the storage medium, and generates a block key from a unique title key and the starting number of the block.

In addition, in the above information reproducing apparatus according to the present invention, the initial block number includes copy control information in addition to the entry time stamp (ATS).

In addition, in the above information reproducing apparatus according to the present invention, when decrypting block data, the cryptographic means decrypts only the data included in the block data with the block key and excludes data in the initial zone including the initial number of the data block.

In addition, in the above information reproducing apparatus according to the present invention, the cryptographic means generates a unique title key from a master key stored in the information reproducing apparatus, a disk identifier, which is an identifier of an information medium unique to an information medium, and a title key unique to data to be recorded on the storage medium uses the unique title key thus generated as a key for the encryption function, in Odita seed block encryption function, and outputs the result as input key block.

In addition, in the above information reproducing apparatus according to the present invention, the cryptographic means generates a unique title key from a master key stored in the information reproducing apparatus, a disk identifier, which is an identifier of an information medium unique to an information medium, and a title key unique to data to be recorded on the information carrier, enters the unique title key generated in this way and the block initial number into a one-way function y and gives the result of the input as a block key.

In addition, in the specified information reproducing apparatus according to this invention, the cryptographic means generates a unique device key from any key of the large integrated circuit stored in the large integrated circuit contained in the cryptographic means, the device key stored in the information reproducing device, the medium key stored in the storage medium and a drive key stored in the drive unit for the storage medium, or a combination of these keys, and generates a block key To decrypt the data block of unique device key generated in this way and a seed block.

In addition, in the specified information reproducing apparatus according to this invention, the cryptographic means decrypts the block data using the block key in accordance with the DES algorithm (data encryption standard).

In addition, said information reproducing apparatus comprises interface means for receiving information to be recorded on the information medium and for identifying copy control information attached to each of the packets included in the transport stream to determine, based on the copy control information, whether or not to play back information carrier.

In addition, said information reproducing apparatus comprises interface means for receiving information to be reproduced from the information medium and identifying the two-bit encryption mode indicator (EMI) as copy control information for determining, based on the EMI, whether or not reproduction from the information medium is allowed.

According to a third aspect of the present invention, a method of recording information on an information medium can be created, the method comprising the steps of: attaching an entry time stamp (ATS) to each of the discrete transport packets included in the transport stream; and generating a block key for encrypting block data including more than one transport packet, each of which has an attached entry time stamp, from the starting number of the block, which is additional information unique to the block data, and includes an entry time stamp, and encrypting each data block using the block key generated in this way; wherein the data encrypted at the cryptographic stage is recorded on a storage medium.

In the above method of recording information according to this invention, a block key is generated at the cryptographic stage for encrypting block data from the initial number of the block, which is additional information unique to the block data and includes an entry time stamp attached to the first packet of the plurality of transport packets included in the data block.

In addition, in the indicated information recording method according to the present invention, a unique title key is generated at the cryptographic stage from the main key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, and generate a block key from a unique title key and the starting number of the block.

In addition, the method for recording information according to this invention comprises the step of generating a disc identifier, which is an identifier of a storage medium unique to the storage medium, and a title key unique to the data to be recorded on the storage medium, and storing them in the storage medium.

In addition, in the method of recording information according to this invention, at the cryptographic stage, only the data included in the block data is encrypted using the block key, and data in the initial zone including the starting number of the block is excluded.

In addition, in the indicated information recording method according to the present invention, a unique title key is generated at the cryptographic stage from the main key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, use the unique title key thus generated as a key for the encryption function, substitute the initial number block into the encryption function and give the result of the substitution as a block key.

In addition, in the indicated information recording method according to this invention, a unique title key is generated at the cryptographic stage from the main key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, substitute the unique title key generated in this way and the initial block number in a one-way function and issue result of substitution as a block key.

In addition, in the specified information recording device according to this invention, a unique device key is generated at the cryptographic stage from any key of a large integrated circuit stored in a large integrated circuit contained in a cryptographic tool, a device key stored in the information recording device, a carrier key, stored in the storage medium, and a drive key stored in the drive unit for the storage medium, or a combination of these keys, and generate a block key for encryption given block from the unique key of the device generated in this way, and the initial number of the block.

In addition, in the specified information recording device according to the invention, at the cryptographic stage, the block data is encrypted using a block key in accordance with the DES algorithm (data encryption standard).

In addition, said information recording method comprises a step for identifying copy control information attached to each of the packets included in the transport stream to determine, based on the copy control information, whether or not writing to the storage medium is allowed.

In addition, said information recording method comprises the step of identifying a two-bit encryption mode indicator (EMI) as copy control information for determining, based on the EMI, whether or not recording is allowed on the storage medium.

According to a fourth aspect of the present invention, a method for reproducing information for reverse reproducing information from an information medium can be created, the method comprising the steps of: generating a block key for decrypting encrypted block data having an entry time stamp attached to each of a plurality of transport packets from an initial number block, which is additional information unique to the block data and includes a timestamp of the entry and decryption of each block of data generated nnym thus block key; control the data output based on the timestamp of the input attached to each of the many transport packets included in the block data, decrypted at the cryptographic stage.

In the above method of reproducing information according to this invention, a block key is generated at the cryptographic stage for decrypting block data from the initial number of the block, which is additional information unique to the block data, and include an entry time stamp attached to the initial packet from a plurality of transport packets included in the data block.

In addition, in the above method of reproducing information according to this invention, a unique title key is generated at the cryptographic stage from the main key stored in the information reproducing device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, and generates a block key from a unique title key and the starting number of the block.

In addition, in the above method of reproducing information according to this invention, when decrypting block data, only the data included in the block data is decrypted using the block key, and data in the initial zone including the initial number of the data block is excluded.

In addition, in the above method of reproducing information according to this invention, a unique title key is generated at the cryptographic stage from the main key stored in the information reproducing device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, use the unique title key thus generated as a key for the encryption function, according to stavlyayut seed block in the encryption function and outputting the result as the substitution block key.

In addition, in the above method of reproducing information according to this invention, a unique title key is generated at the cryptographic stage from the main key stored in the information reproducing device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, substitute the unique title key generated in this way and the block starting number in a one-way function tion and outputting the result of substitution as the block key.

In addition, in the specified method of reproducing information according to this invention, a unique device key is generated at the cryptographic stage from any key of a large integrated circuit stored in a large integrated circuit contained in a cryptographic tool, a device key stored in the information reproducing device, a media key, stored in the storage medium and a drive key stored in the drive unit for the storage medium, or a combination of these keys, and generate a block key for I am decrypting the block data from the unique key of the device generated in this way and the starting number of the block.

In addition, in the specified method of reproducing information according to this invention, at the cryptographic stage, the block data is decrypted using the block key in accordance with the DES algorithm (data encryption standard).

In addition, the method for reproducing information comprises the step of identifying copy control information attached to each of the packets included in the transport stream to determine, based on the copy control information, whether or not playback from the storage medium is allowed.

In addition, the method for reproducing information includes the step of identifying a two-bit encryption mode indicator (EMI) as copy control information for determining, based on the EMI, whether or not playback from the information medium is allowed.

According to a fifth aspect of the present invention, a storage medium can be created having block data recorded thereon, including more than one packet included in the transport stream and having an entry time stamp (ATS) attached to each of the packets, wherein the block data comprises: an unencrypted part data having a random block number including an entry time stamp from which a block key is generated for encrypting the block data; and an encrypted piece of data encrypted with a block key.

According to a sixth aspect of the present invention, a program maintenance tool can be created that services a computer program, according to which information is recorded on a storage medium in a computer system, the computer program comprising the steps of: attaching an entry time stamp (ATS) to each of the discrete transport packets included in the transport stream; and generating a block key for encrypting the block data, including more than one packet, each of which has an attached entry time stamp, from the initial number of the block, which is additional information unique to the block data and including the entry time stamp, and encrypting all the block data with the block key generated in this way.

According to a seventh aspect of the present invention, a program maintenance tool can be created that serves a computer program, according to which information is reproduced from an information medium in a computer system, the computer program comprising the steps of: generating a block key for decrypting encrypted block data having a time stamp input attached to each of the many transport packets from the initial number of the block, which is additional information, un Kalnoy for the block of data consisting of input time stamp and decrypt the block of data using thus generated block key; and processing a transport stream to control data output based on an entry time stamp attached to each of a plurality of transport packets included in the block data decrypted at the decryption stage.

According to the present invention, the content to be recorded on the storage medium is formed from TS packets defined in MPEG-2, and each packet is recorded on the storage medium together with an entry time stamp, which is information about the time at which the packet is recorded by the recording device. ATS stands for entry timestamp and is 24 to 32 bit data.

The number X of TS packets, each of which has an entry time stamp attached to it, is recorded in one block (sector) of the storage medium, and the entry time stamp attached to the first TS packet is used to generate a block key for encrypting data in the block.

Thus, the data in each block can be encrypted with a unique block key without the need to provide a special area for storing the key and access to any data except the main data during recording and playback.

In addition, in addition to the entry time stamp (ATS), the copy control information (CCI) can be attached to the TS packet to be recorded and ATS and CCI can be used to generate the block key.

It should be noted that the program maintenance means, according to the sixth and seventh aspects of the present invention, are means that service a computer program in a form suitable for reading by a computer in a general-purpose computer system capable of executing various program codes. The tool is not limited to any special form, but can be any storage medium, such as CD, FD, MO, etc., as well as a transmission medium, such as a network.

The specified program maintenance tool determines the structural and functional interaction between a computer program and a means for performing the functions of a given computer program in a computer system.

Brief Description of the Drawings

These objectives and other objectives, features and advantages of the present invention follow from the following detailed description of preferred embodiments of the present invention with reference to the accompanying drawings, in which:

1 is a block diagram of an information recording / reproducing apparatus according to a first example of the present invention;

2 is a block diagram of an information recording / reproducing apparatus according to a second example of the present invention;

figa and 3B is a sequence diagram of operations performed in the process of recording information in the device recording / reproducing information according to this invention;

figa and 4B is a sequence diagram of operations performed in the process of reproducing information in the device recording / reproducing information according to this invention;

5 is a data format processed in an information recording / reproducing apparatus according to this invention;

6 is a block diagram of a means of processing a transport stream (TS) in a device for recording / reproducing information according to this invention;

7A-7C show a transport stream processed in an information recording / reproducing apparatus according to this invention;

Fig. 8 is a block diagram of a transport stream (TS) processing means in an information recording / reproducing apparatus according to the present invention;

Fig.9 is a block diagram of a means of processing a transport stream (TS) in a device for recording / reproducing information according to this invention;

10 is an example of additional information of block data processed in an information recording / reproducing apparatus according to this invention;

11 is a block diagram (1) of encryption performed to record data in an information recording / reproducing apparatus according to this invention in a system with which data should be compatible;

12 is a flowchart (2) of encryption performed to record data in an information recording / reproducing apparatus according to this invention in a system with which data should be compatible;

FIG. 13 is a flowchart of encryption for recording data in an information recording / reproducing apparatus according to the present invention in a system with which data should be compatible;

Fig - generating a block key in a device for recording / reproducing information according to this invention;

Fig - block diagram of decryption performed to reproduce data in a device for recording / reproducing information according to this invention, in a system with which data should be compatible;

FIG. 16 is a flowchart for decoding to reproduce data in an information recording / reproducing apparatus according to the present invention in a system with which data should be compatible;

17 is a block diagram of an encryption performed to record data in an information recording / reproducing apparatus according to the present invention in a system with which data should not be compatible;

Fig. 18 is a flowchart of encryption for recording data in an information recording / reproducing apparatus according to the present invention in a system with which data should not be compatible;

Fig. 19 is an example (1) of generating a unique device key in an information recording / reproducing apparatus according to this invention in a system with which data should not be compatible;

FIG. 20 is an example (2) of generating a unique device key in an information recording / reproducing apparatus according to the present invention in a system with which data should not be compatible;

21 is a decryption block diagram for reproducing data in an information recording / reproducing apparatus according to the present invention in a system with which data should not be compatible;

FIG. 22 is a flowchart for decoding for reproducing data in an information recording / reproducing apparatus according to the present invention in a system with which data should not be compatible;

23 is a block diagram (1) of encryption for recording data in an information recording / reproducing apparatus according to the present invention in a system in which restrictions can be set for a reproducing apparatus;

24 is a block diagram (1) of encryption for recording data in an information recording / reproducing apparatus according to the present invention in a system in which restrictions can be set for a reproducing apparatus;

25 is a flowchart of an information recording / reproducing apparatus according to the present invention, in a system in which restrictions can be set for a reproducing apparatus;

FIG. 26 is an example of generating a unique disc key in an information recording / reproducing apparatus according to the present invention; FIG.

Fig. 27 is a flowchart for generating a unique title key in an information recording / reproducing apparatus according to the present invention, in a system in which restrictions can be set for a reproducing apparatus;

FIG. 28 is an example of generating a unique title key for recording data in an information recording / reproducing apparatus according to the present invention in a system in which restrictions can be set for a reproducing apparatus;

Fig. 29 is a decoding block diagram for reproducing data in an information recording / reproducing apparatus according to the present invention in a system in which restrictions can be set for a reproducing apparatus;

FIG. 30 is a flowchart for reproducing data in an information recording / reproducing apparatus according to the present invention in a system in which restrictions can be set for a reproducing apparatus;

FIG. 31 is a decision diagram about the possibility or impossibility of reproducing data in an information recording / reproducing apparatus according to this invention in a system in which restrictions can be set for a reproducing apparatus;

32 is a flowchart for generating a unique title key for reproducing data in an information recording / reproducing apparatus according to the present invention in a system in which restrictions can be set for a reproducing apparatus;

33A and 33B are flowcharts for managing copying when recording data in an information recording / reproducing apparatus according to the present invention;

FIGS. 34A and 34B are flow diagrams for managing copying in reproducing data in an information recording / reproducing apparatus according to the present invention;

Fig. 35 is a block diagram of a data processing system using software in an information recording / reproducing device.

Preferred Embodiment

[System configuration]

Figure 1 schematically shows a block diagram of an embodiment of a device for recording / reproducing information according to this invention. The recording / reproducing device is generally indicated by 100. As shown in the figure, the recording / reproducing device 100 comprises an input / output interface 120, an MPEG codec 130 (cinema expert panel), an input / output interface 140 comprising an analog-to-digital combiner 141 converter and digital-to-analog converter, cryptographic unit 150, ROM 160 (read-only memory), central processor 170, memory 180, drive 190 for storage medium 195, and transport stream processing means 300 (processor p TS). The components are connected to each other by a bus 110.

The input / output interface 120 receives digital signals included in each of various contents, such as an image, sound, program, or the like, supplied from the outside, and feeds them to the bus 110 as well as to the outside. MPEG codec 130 performs MPEG decoding of MPEG-encoded data supplied via bus 110 and outputs MPEG-decoded data to input / output interface 140 while simultaneously MPEG encoding digital signals supplied from input / output interface 140 and outputs data to bus 110 The input / output interface 140 includes a combination device 141 of an analog-to-digital converter and a digital-to-analog converter. The input / output interface 140 receives the analog signals as external content, performs analog-to-digital data conversion, and outputs the digital signals thus obtained to the MPEG codec 130, while performing digital-to-analog conversion of the digital signals from the MPEG codec 130 and outputting the analog signals obtained therefrom .

The cryptographic unit 150 is made, for example, in the form of a single-chip large integrated circuit. It encrypts or decrypts digital signals in content received via bus 110 and outputs data to bus 110. It should be noted that the cryptographic unit is not limited to a single-chip large integrated circuit, but may be a combination of various types of software or hardware. A program type cryptographic block will be further described below.

In ROM 160, a device key is stored that is unique, for example, for each recording / reproducing device or for a group of multiple recording / reproducing devices. The central processor 170 executes a program stored in the memory 180 to control the MPEG codec 130, the cryptographic unit 150, etc. The memory 180 is, for example, a non-volatile memory for storing, for example, a program to be executed by the central processor 170, and data necessary for the central processor 170 to operate. The drive 190 implements the drive of the information medium 195 capable of recording digital data to read digital data from the storage medium 195 and outputs data to the bus 110, while simultaneously supplying digital data supplied via the bus 110 to the recording medium 195. It should be noted that the device 100 recording / playback can be performed so that the ROM 160 stores the program, while the memory 180 stores the keys of the device.

The storage medium 195 is a means capable of storing digital information, such as one of the optical disks, including DVD, CD, etc., a magneto-optical disk, a magnetic disk, magnetic tape or semiconductor storage devices including RAM (RAM) and the like . In this embodiment, the storage medium 195 is removable in the drive 190. However, it should be noted that the storage medium 195 can be integrated into the recording / reproducing device 100.

The transport stream processing means 300 (TS processor) retrieves transport packets related to a given program (content), for example, from a transport stream including a plurality of television programs multiplexed therein, stores information about the time the extracted transport packet appeared together with each packet in the medium 195 information and controls the time of appearance of the transport stream for reading from the media 195 information. A further description of the processor 300 TS will be given below with reference to Fig.6 and the following figures.

A transport timestamp (ATS) is set for the transport stream as the time that each of the transport packets appeared in the transport stream. The appearance time is determined during encryption to prevent the failure of the final decoder of the transport stream system (T-STD), which is a virtual decoder defined in MPEG-2 systems, and during the reading of the transport stream, the appearance time is monitored using an entry time stamp attached to each transport package. The processor 300 TS performs these types of control. For example, when transport packets are written to the storage medium, transport packets are recorded as source packets located without a gap between consecutive packets, and the time of appearance of each packet remains unchanged, which provides control of the exit time of each transport packet during reading from the information carrier. A processor 300 TS attaches an entry time stamp (ATS) indicating the time at which each of the transport packets was received when data is recorded on the storage medium 195, such as a DVD.

In the recording / reproducing apparatus 100 according to the present invention, content including a transport stream in which an entry time stamp is attached to each transport packet is encrypted using a cryptographic unit 150, and the content encrypted in this manner is stored on the information medium 195. In addition, the cryptographic unit 150 decrypts the encrypted content stored on the information medium 195. A description of this encryption and decryption will be described in detail below.

It should be noted that in FIG. 1, the cryptographic unit 150 and the TS processor 300 are shown as separate units for ease of illustration and explanation, however, these functions can be integrated into a single-chip large integrated circuit or performed using a combination of software and hardware elements.

In addition to the structure shown in FIG. 1, the recording / reproducing apparatus according to the present invention may have the structure shown in FIG. 2. The recording / reproducing apparatus shown in FIG. 2 is indicated generally by 200. In the recording / reproducing apparatus 200, the information carrier 195 is removably mounted to the information carrier interface 210, which is implemented as a drive unit. Writing data to a storage medium 195 and reading data from it is also possible when it is used in another recording / reproducing device. As shown in FIG. 2, in a recording / reproducing device in which a storage medium 195 compatible with more than one recording / reproducing device can be used, the unique key of the device is not used, but the key common to all such recording / reproducing devices is t .e. the shared key for the entire system is stored in memory 180.

[Recording and playing back data]

Figures 3 and 4 show graphical diagrams of operations performed when writing data to a storage medium in the recording / reproducing apparatus shown in Figures 1 or 2, and when reading data from a storage medium. To record digital signals as content on the storage medium 195, the operations shown in the diagram of FIG. 3A are performed. Namely, when digital signals as content (digital content) are supplied to the input / output interface 120 via the IEEE (Institute of Electronics and Electrical Engineers) 1394 serial bus or the like, the input / output interface 120 receives the digital content and outputs data to the TS processor 300 via the bus 110 in step S301.

In step S302, the TS processor 300 generates block data in which an entry time stamp is attached to each of the transport packets in the transport stream, and provides data to the cryptographic block 150 via the bus 110.

In step S303, the cryptographic unit 150 encrypts the received digital content and outputs the encrypted content to the drive 190 or the storage medium interface 210 via the bus 110. In step S304, the encrypted digital content is recorded to the storage medium 195 through the drive 190 or the storage medium interface 210. Here, the recording / reproducing apparatus exits the recording procedure. A description of encryption using the cryptographic unit 150 is given below.

It should be recalled that as a standard for the protection of digital content transmitted between devices via the IEEE 1394 serial bus, the protection “5CDTCP (Digital Content Transmission Protection of Five Companies)” (hereinafter referred to as DTCP) was established by five companies, including Sony Corporation, which is the applicant of this invention. It stipulates that in the case of transferring digital content that is not free for copying between devices, the transmission side and the receiving side must mutually confirm before transferring that the copy control information can be correctly processed, then the digital content is encrypted on the transmitting side for transmission, and the encrypted digital content (encrypted content) is decrypted on the receiving side.

When transmitting and receiving data using this DTCP standard, the input / output interface 120 on the data receiving side receives encrypted content via the IEEE 1394 serial bus, decrypts the encrypted content in accordance with the DTCP standard, and then outputs the data as open or decrypted content to the cryptographic unit 150 ( in step S301).

For encryption based on DTCP digital content, it is necessary to generate a time-varying key. The encrypted digital content, including the key used for encryption, is transmitted via the IEEE 1493 serial bus to the receiving side, and the receiving side decrypts the encrypted digital content with the key included in the content.

More specifically, the DTCP standard provides that the initial key value and a flag indicating the key change time for encrypting digital content are included in the encrypted content. On the receiving side, the initial key value included in the encrypted content changes at the time indicated by the flag included in the encrypted content to generate the key that was used for encryption, and the encrypted content is decrypted with the key generated in this way. Namely, it can be considered that the encrypted content includes a key used to decrypt it, and this position should be fulfilled in the following description. In accordance with the DTCP standard, there is an information version, for example, a Web page identified by a URL (Unified Resource Locator), http://www.dtcp.com.

The following is a description of the recording of analog signals as content on the storage medium 195 with reference to the circuit shown in figv. When the input / output interface 140 receives the analog signals as content (analog content) in step S321, the process proceeds to step S322, where the combined analog-to-digital converter and digital-to-analog converter 141 performs analog-to-digital conversion of the analog content to create digital signals in content quality (digital content).

The digital content is supplied to the MPEG codec 130, which performs MPEG encoding of the digital content in step S323, namely the encoding of the digital content by MPEG compression, and supplies the encoded content to the cryptographic unit 150 via the bus 110.

In subsequent steps S324, 325, and 326, operations similar to those in steps S302 and 303 of FIG. 3A are performed. Thus, the TS processor 300 attaches an entry time stamp to each of the transport packets, the cryptographic unit 150 encrypts the content, and the encrypted content obtained therewith is recorded on the information medium 195. Here, the recording / reproducing apparatus exits the recording procedure.

The following is a description of the operations performed to reproduce content from the storage medium 195 and the issuance of digital or analog content, with reference to the diagram in figure 4. This is done according to the circuit shown in FIG. 4A. First, in step S401, the encrypted content is read from the storage medium 195 using the drive 190 or the storage medium interface 210 and provided through the bus 110 to the cryptographic unit 150.

In step S402, the cryptographic unit 150 decrypts the encrypted content received from the drive 190 or the storage medium interface 210 and provides the decrypted data to the TS processor 300 via the bus 110.

In step S403, the TS processor 300 determines the exit time based on the entry time stamp attached to each of the transport packets included in the transport stream to perform control in accordance with the entry time stamp and provides data to the input / output interface 120 via the bus 110. It should note that the processing operations in the processor 300 TS and the decryption of digital content in the cryptographic unit 150 will be further described below.

It should be noted that when digital content is delivered through the IEEE 1394 serial bus, the input / output interface 120 performs mutual authentication in step S404 with the communicating device, as mentioned above, in accordance with the DTCP standard, and then encrypts the digital content for transmission.

To read the content from the storage medium 195 of information and to provide it in the form of analog content, the playback operations shown in the diagram of FIG. 4B are performed.

Namely, in successive steps S421, 422 and 423, operations similar to those performed in steps S401, 402 and 403 of FIG. 4A are performed. Due to this, the decrypted digital content received from the cryptographic unit 150 is supplied to the MPEG codec 130 via the bus 110.

At step S424, the codec 130 performs MPEG decoding of the digital content, namely, restores the compressed digital data, and feeds the data to the input / output interface 140. In step S425, the input / output interface 140 performs digital-to-analog conversion of the digital content subjected to MPEG decoding in the codec 130 in step S424 using the combined analog-to-digital converter and digital-to-analog converter. Then, the input / output interface 140 proceeds to step S426, where it outputs the analog content. On this, the recording / reproducing apparatus exits the reproducing procedure.

[Data Format]

The following is a description of the format of the data recorded or read from the storage medium according to this invention, with reference to figure 5. A minimum element read or written to a storage medium according to this invention is called a block. One block has a size of 192 * X bytes (for example, X = 32).

According to this invention, an entry time stamp (ATS) is attached to each packet (out of 188 bytes) of TS (transport stream) defined in MPEG-2 to create data from 192 bytes, and X of such data is considered to be one block. The entry time stamp contains data of 24-32 bits indicating the entry time. As indicated above, ATS stands for entry timestamp. The entry time stamp is random data corresponding to the entry time of each packet. X TS packets (transport stream) are recorded in one block (sector) of the information carrier, each of which is connected with an entry time stamp. According to the present invention, an entry time stamp attached to the first of the TS packets in each of the blocks included in the transport stream is used to generate a block key, which is used to encrypt data in each block (sector).

A key unique to each block is generated by generating an encrypted block key based on a random entry timestamp. A key created in such a way that is unique to a block is used to encrypt each block. In addition, by generating a block key based on an entry time stamp, there is no need to provide a zone on the information medium for storing the encryption key for each block, and it becomes possible to efficiently use the main data zone on the information medium. In addition, during playback, there is no need to access data other than that contained in the main zone, which provides more efficient recording or playback.

It should be noted that the starting block number shown in FIG. 5 is additional information including an entry time stamp. The block starting number may also include copy control information (CCI) in addition to the entry time stamp. In this case, the copy control information and the entry time stamp are used to generate the block key.

It should be noted that, according to this invention, most of the data in the content stored on a storage medium such as DVD is encrypted. As shown in the bottom of figure 5, m bytes (for example, m = 8 or 16 bytes) in the initial part of the block are written as open, or unencrypted, data, while the rest of the data (m + 1 onwards) is encrypted, since the length of the encrypted data is limited since encryption is performed in modules of 8 bytes. It should be noted that if encryption was performed, for example, in modules of 1 byte, and not in modules of 8 bytes, then all data, except for the initial number of the block, could be encrypted using a series of 4 bytes in the initial part of the block ( m = 4).

[Operations performed by TS processor]

The following is a detailed description of the ATS function. As indicated above, the ATS is an entry time stamp attached to each of the transport packets included in the transport stream to save the entry time of the TS packet.

Thus, when, for example, one or more transport packets included in a transport stream is extracted from a plurality of television programs (contents) multiplexed in a transport stream, they arrive at irregular intervals (see FIG. 7A). The time that each of the transport packets in the transport stream enters is important for the transport stream, and the entry time is determined during coding to prevent failures of the final decoder of the transport stream system (T-STD), which is a virtual decoder defined in MPEG-2 systems (ISO / IEC 13818-1).

During playback of the transport stream, the entry time is controlled based on the entry time stamp attached to each transport packet. Therefore, when recording transport packets to the storage medium, it is necessary to save the entry time of the transport packet. When recording transport packets to a storage medium, such as a DVD, an entry time stamp is attached to each transport packet, indicating the entry time of each transport packet to be recorded on the storage medium.

6 is a flowchart illustrating operations performed in the TS processor 300 when recording a transport stream transmitted via a digital interface to a storage medium such as a DVD. As shown in the figure, the transport stream is transmitted in the form of digital data, such as digital broadcast signals, from the terminal 600 to the TS processor 300. As shown in FIGS. 1 or 2, a transport stream is transmitted from terminal 600 via an input / output interface 120 or an input / output interface 140 and an MPEG codec 130.

The transport stream is transmitted to a bitstream parser 602, which detects a PCR packet (software reference time indicator) in the incoming transport stream. A PCR packet is a packet in which a PCR encoded as defined in MPEG-2 systems is encoded. PCR packets are encoded at time intervals of less than 100 ms. PCR represents the time when the transport packet comes to the receiving side, with an accuracy of 27 MHz.

Then, the 27 MHz phase lock (PLL) circuit 603 matches the 27 MHz clock generator of the recording / reproducing device with the PCR of the transport stream. A timestamp generating circuit 604 generates a timestamp based on a 27 MHz clock. The block seed attachment circuit 605 attaches a time stamp to the transport stream indicating the time when the first byte of the transport packet enters the smoothing buffer 606 as an entry time stamp (ATS).

A transport packet with an entry time stamp attached to it leaves the terminal 607 via a smoothing buffer 606 and into a cryptographic unit 150, in which it is encrypted, as will be further described below, and then written to the information carrier 195 using the drive 190 (see FIG. 1) and media interface 210 (see FIG. 2).

7 shows, by way of example, the operations performed to record an incoming transport stream to a storage medium. On figa shows the input of transport packets included in a specific program (content). On the horizontal axis in FIG. 7A, a time scale is shown indicating the transport flow time. As shown in FIG. 7A, in this embodiment, the transport packets in the incoming transport stream come through irregular times.

On figv shows the output signal of the circuit 605 joining the initial number of the block. This circuit 605 attaches a random number including an entry time stamp indicating the arrival time of each of the transport packets of the transport stream to the transport packet and provides an original packet. On figs shows the source packets recorded on the storage medium. As shown in FIG. 7C, source packets are recorded on a storage medium without a gap between successive packets. Due to this arrangement of the source packets without a gap between them, it is possible to efficiently use the recording area on the storage medium.

FIG. 8 is a flowchart of a TS processor 300 illustrating a data processing procedure for reading a transport stream from an information medium 195. The transport packet, decrypted in a cryptographic block, which will be further described below, and having an entry time stamp attached thereto, is supplied from the terminal 800 to the block initial number separation circuit 801, where the entry time stamp and the transport packet are separated from each other. Here, a timing circuit 804 is provided for calculating time based on a clock count of a clock generator 805 at a frequency of 27 MHz of a reproducing apparatus.

It should be noted that the first entry timestamp is set as the initial value in the synchronization circuit 804. A comparator 803 is also provided for comparing the entry timestamp with the current time transmitted from the synchronization circuit 804. An output control circuit 802 is also provided for issuing a transport packet to the MPEG codec 130 or the digital input / output interface 120 when the time generated by the synchronization circuit 804 becomes equal to the time stamp of the input.

FIG. 9 shows MPEG coding of input audio-visual signals in an MPEG codec 130 of an MPEG recording / reproducing apparatus 100 and coding of a transport stream in a TS processor 300. Namely, FIG. 9 is a flowchart illustrating both the MPEG codec 130 shown in FIGS. 1 or 2 and the TS processor 300. Video signals are transmitted from terminal 901 to the MPEG video encoder 902.

An MPEG video encoder 902 encodes the input video signals into an MPEG video stream and provides data to a video stream buffer 903. MPEG video encoder 902 also provides MPEG video access module information to a multiplex manager 908. The "access module" of the video stream contains the type, number of encoded bits, and a decoding time stamp for each frame. The frame type is I / P / B frame information, and the decoding time stamp is information defined in MPEG-2 systems.

Audio signals are provided from terminal 904 to MPEG audio encoder 905. The MPEG audio encoder 905 encodes the input audio signals into the MPEG audio stream and outputs the data to the buffer 906. The MPEG audio encoder 905 also outputs the information of the MPEG audio stream access module to the multiplex manager 908. The audio stream access module is an audio frame, and the access module information contains the number of encoded bits and a decoding time stamp of each audio frame.

Both video access information and audio access information are supplied to the multiplexing manager 908, and it controls the encoding of the video and audio streams based on the access module information. The multiplexing manager 908 includes a clock for generating a reference time with an accuracy of 27 MHz, and thereby sets the packet encoding control information for the transport packet in accordance with the T-STD, which is a virtual model of the decoder defined in MPEG-2. The packet coding control information contains the type and length of the stream to be packetized.

In the case where the encoding control information packet belongs to a video packet, the switch 976 is placed on the part of a buffer 903 for reading the video stream from the payload data length specified in the packet control information coding and supplies the data to the encoder 909 of transport packets.

In the case where the packet encoding control information relates to audio packets, the switch 976 is placed on the b side of the audio stream buffer 906 to read audio data with the payload length indicated in the packet encoding control information and provides data to the transport packet encoder 909.

In the case where the packet coding control information relates to PCR packets, the transport packet encoder 909 receives the PCR supplied from the multiplexing manager 908 and outputs the PCR packets. If the packets are not encoded with coding control information, nothing is supplied to the transport packet encoder 909.

If the packets are not encoded with coding control information, the transport packet encoder 909 does not issue packets. Otherwise, transport packets are created based on the packet encoding control information and are output. Therefore, the transport packet encoder 909 intermittently provides transport packets. An entry time stamp calculator 910 is also provided for calculating an entry time stamp indicating the time at which the first byte of the transport packet arrives at the receiving side based on the PCR supplied from the multiplex manager 908.

Since the PCR (software reference time indicator) supplied from the multiplexing manager 908 indicates the time at which the tenth byte of the transport packet defined in MPEG-2 arrives at the receiving side, the entry timestamp value corresponds to the byte arrival time 10 bytes before the time indicated by PCR.

The block seed attachment circuit 911 attaches an entry time stamp to each of the packets output by the transport packet encoder 909. A transport packet with an attached timestamp attached from the initial number attachment circuit 911 is supplied to the cryptographic unit 150 via a smoothing buffer 912, where it is encrypted, as will be further described below, and then stored on the information medium 195.

To save on the information carrier 195, transport packets with an attached timestamp are located without a gap between them, as shown in FIG. 7C, and then are stored on the information carrier 195 before encryption is performed in the cryptographic unit 150. Even if the transport packets are located without a gap between them , then referring to the entry time stamp attached to each of the packets provides the ability to control the time of delivery of transport packets to the receiving side.

It should be noted that the size of the entry timestamp is not limited to 32 bits, but can range from 24 to 32 bits. The longer the bit length of the entry timestamp, the longer the operating cycle of the time counter indicated by the entry timestamp. For example, in the case where the time counter is a binary counter with an accuracy of 27 MHz, then a 24-bit entry timestamp will reappear after about 0.6 s. This time interval is long enough for a normal transport stream, since the packet interval of the transport stream is defined in MPEG-2 as a maximum of 0.1 s. However, the bit length of the entry timestamp may be more than 24 bits for sufficient tolerance.

Due to the indicated change in the length in bits of the timestamp of the input, the configuration of the seed, which is additional data for the block data, can be of several types. Examples of the configuration of the starting number of the block are shown in FIG. 10. Figure 10 shows an example 1 of a seed when using a 32-bit entry timestamp. Figure 10 shows an example 2 of a seed when using an entry time stamp of 30 bits and copy control information (CCI) of 2 bits. Copy control information indicates a monitored state of copying data having copy control information attached thereto. SCMS (Sequential Copy Management System) and CGMS (Copy Management System) are best known as copy management information. This copy control information indicates that data with copy control information attached to it is allowed for unlimited copying (free to copy), data is allowed to be copied only once (allowed for one-time copying), or data is prohibited for copying (data prohibited for copying) .

Figure 10 shows an example 3 of the starting number of a block using a 24-bit input timestamp, 2-bit copy control information, and other 6-bit information. Other information can be selected from various types of information, such as information indicating the on / off operation of the Macrovision system, which is a copy control mechanism for analog video data when block starting number data is output in analog form.

[Encryption when recording data in the system with which the recorded data must be compatible]

The following is a description of the encryption that is performed when recording data in a system with which recorded data should be compatible, namely, in a system in which a storage medium having data recorded thereon by one recording / reproducing device must be reproduced by another recording / reproducing device. The system with which the recorded data is to be compatible is, for example, the recording / reproducing apparatus 200 shown in FIG. Thus, a storage medium having data recorded thereon by the recording / reproducing apparatus 200 can be reproduced in another recording / reproducing apparatus.

The following is a description of the encryption when recording data in such a system with reference to the flowcharts of FIGS. 11 and 12 and the graphic diagram of FIG. As an information carrier, an optical disc is subsequently adopted. This embodiment is a system with which recording data must be compatible, that is, a system in which data recorded in one recording / reproducing device can be reproduced in another recording / reproducing device, as indicated in Japanese Published Application No. 224461 from 1999 ( Japanese Patent Application No. 25310 of 1998). To prevent bitwise copying of data recorded on the storage medium, the disk identifier, as identification information unique to the storage medium, acts as an encryption data key.

The following is a description of data encryption using a cryptographic unit 150 with reference to the flowcharts of FIGS. 11 and 12.

The recording / reproducing apparatus 1100 reads the master key 1101 stored in its own memory 180 (see FIG. 2). The master key 1101 is a private key stored in a licensed recording / reproducing device, as well as a shared key for a plurality of recording / reproducing devices, namely, the entire system. The recording / reproducing apparatus 1100 checks whether the disc identifier 1103 as the identification information is already recorded on the information medium 1120, which is, for example, an optical disc. If it is determined that the disc identifier 1103 is recorded on the storage medium 1120, then the recording / reproducing apparatus 1100 reads the disc identifier 1103 (as shown in FIG. 11). If not, then the cryptographic unit 150 in the recording / reproducing apparatus 1100 generates a disk identifier 1201 randomly or by generating a predetermined random number and writes the disk identifier 1201 to the disk (as shown in FIG. 12). Only one such identifier 1103 must be available for each disk, so that the disk identifier can be stored, for example, in the input area of the disk.

Then, the recording / reproducing apparatus 1100 generates a unique disc key from the master key and the disc identifier (as indicated by 1102). In particular, a unique disk key is generated, for example, by substituting data obtained by bitwise combination of the master key and disk identifier in the SHA-1 hash function defined in FIPS 180-1 to ensure the issuance of 160 bits and retrieve only data of the required length from 160 bit output for use as a unique disk key, by substituting the master key and disk identifier in a hash function based on the block encryption function and using the result of the substitution, or other way.

Then, a unique title key is generated for each record (as indicated by 1104) according to a random law or by generating a given random number in the cryptographic unit 150 and is written to the disk 1120. The disk 1120 contains a data management file in which information is recorded which title is generated from the data and where the data came from, and can save the title key in a file.

Then, a unique cover key is generated from the unique drive key and cover key. It can be generated in various ways, for example, using the SHA-1 hash function or a hash function based on the encryption function of the data block.

As mentioned above, a unique drive key is generated from the master key and drive ID, and a unique cover key is generated from a unique drive key and cover key. However, you can generate a unique title key directly from the master key and disk identifier without generating a unique disk key, or you can generate a key equivalent to a unique title key from the master key and disk identifier without using the title key.

It should be borne in mind that in the case of using one of the data transmission formats defined, for example, in the above DTCP standard, data is transmitted in some cases as TS MPEG-2 packets. For example, when a set-top box (STB), which received the program from the satellite, transmits the program to the recorder without using the DTCP transfer format, the set-top box also preferably transmits TS MPEG-2 packets transmitted over the satellite broadcast channel on the IEEE 1394 serial bus, since data conversion not required.

The recording / reproducing apparatus 1100 receives the content data to be recorded as TS packets at the time that the TS packet was received. It should be noted that, as indicated above, the initial block number attached to the block data may consist of a combination of the entry time stamp, copy control information, and other information.

The number X (for example, X = 32) of the TS packets, each of which has an entry time stamp attached thereto, are adjacent to each other to form one data block (shown at the top of FIG. 5). As shown at the bottom of FIG. 11 and 12, 1 to 4 bytes in the initial part of the block data transmitted for encryption are separated (in the selector 1108) to provide the initial number of the block, including an entry time stamp of 32 bits. The block key, which is the encryption key for the data in the block, is generated (as indicated by 1107) from the starting number of the block and the previously generated unique title key.

On Fig shows an example of generating a block key. 14 shows two examples of generating a 64-bit block key from a 32-bit block seed and a 64-bit unique title key.

In Example 1, shown in the upper half of FIG. 14, an encryption function is used, the key length of which is 64 bits, and the input and output signals are 64 bits respectively. A unique title key is used as the key for this function, a combination of the initial number of the block and a constant of 32 bits is entered into the encryption function, and the input result is accepted as a block key.

Example 2 uses the SHA-1 hash function defined in FIPS 180-1. The combination of a unique title key and the starting number of the block is entered into the SHA-1 hash function, and the output signal from 160 bits is reduced to 64 bits when, for example, only the lower 64 bits are used. These 64 bits are used as a block key.

The above is a description of examples of generating a block key in which a unique disk key, a unique title key, and a block key are generated. However, a block key can be generated from a master key, a disk identifier, a title key, and a block starting number for each block without generating a unique disk key and a unique title key.

The block key generated in this way is used to encrypt the block data. As shown in the lower parts of FIG. 11 and 12, the first m bytes (for example, m = 8) in the initial part of the block data, including the initial number of the block, are separated (in the selector 1108) so as not to be encrypted, and the bytes from (m + 1) to the last are encrypted (as indicated by 1109). It should be noted that m bytes that are not encrypted include the first to fourth bytes as the starting number of the block. The data bytes of the block from m + 1 onwards selected in the selector 1108 are encrypted (as indicated by 1109) in accordance with the encryption algorithm specified in the cryptographic unit 150. The encryption algorithm may be, for example, DES (data encryption standard) defined in FIPS 46-2.

When the length of the block (the size of the input / output data) in the encryption algorithm used is 8 bytes, as in DES, then all the data of the block, including bytes (m + 1) and the following without a remainder, can be encrypted, for example, at X = 32 and m is a multiple of 8.

Namely, in the case when X TS packets are stored in one block, the size of the input / output data of the encryption algorithm is L bytes, n is an arbitrary natural number defining X, m and L so that 192 * X = m + n * L , which makes processing the remainder unnecessary.

The encrypted last bytes (m + 1) of the block data are combined with the first unencrypted m bytes of the block data using the selector 1110 and stored as encrypted content 1112 on the storage medium 1120.

Using the above operations, the content is encrypted block by block with a block key generated from the initial number of the block, including the entry time stamp, and stored on the storage medium. As mentioned above, since the entry timestamp contains random data unique to the block, the block keys generated based on the entry timestamp set for each block are different from each other. Thus, the encryption key changes from block to block and thereby provides enhanced data protection from cryptographic analysis. Using the starting number of the block as data to generate the encryption key eliminates the need to store the encryption key for each block separately from the data. Thus, a special storage area for the encryption key is not required, and the storage area of the storage medium can be effectively used. Since the initial number of the block contains data that can be written and read along with the content data, it is possible to abandon the operation of writing or reading data to generate an encryption key during writing or reading data, which differs from conventional systems in which the encryption key must be stored in a zone other than the data zone. Thus, recording and reproduction of information can be performed with higher efficiency.

The following is a description of the sequence of operations performed by attaching an entry time stamp using a TS processor 300 and encrypting the recorded data with a cryptographic unit 150, with reference to the graphic circuit in FIG. 13. In step S1301 of FIG. 13, the recording / reproducing device reads the master key stored in its own memory 180.

In step S1302, the recording / reproducing apparatus checks whether a disc identifier is already recorded on the storage medium as identification information. When it is determined that the disc identifier is recorded, in step S1303, the recording / reproducing apparatus reads the disc identifier. If it is determined that the disc identifier has not been recorded, the recording / reproducing device generates a disc identifier according to a random law or using a predetermined method and writes it in step S1304 to a disc (storage medium). Then, in step S1305, the recording / reproducing apparatus generates a unique disc key from the master key and the disc identifier. As mentioned above, a unique disk key is generated using, for example, the SHA-1 hash function defined in FIPS 180-1, or a hash function based on the block encryption function.

Then, in step S1306, the recording / reproducing apparatus generates a title key as a key unique to each recording, and writes it to a disc. Then, in step S1307, the recording / reproducing device generates a unique title key from the unique disc key and title key using, for example, a SHA-1 hash function or a hash function based on the block encryption function.

In step S1308, the recording / reproducing apparatus receives data obtained from the content data to be recorded in the form of TS packets. In step S1309, the TS processor 300 attaches an entry time stamp to each TS packet that contains information about the time at which the TS packet was received. Alternatively, the TS processor 300 attaches to each TS packet a combination of entry timestamps, copy control information, and other information. Then, in step S1310, the recording / reproducing device receives TS packets one after the other, an entry time stamp is attached to each of them, and determines whether, for example, the number X = 32 of the TS packets forming one block is received or if identification data indicating latest TS package. When one of these conditions is met, the recording / reproducing device in step S1311 places X TS packets or TS packets up to the last packet adjacent to each other to form one data block.

Then, in step S1312, the cryptographic unit 150 generates a block key for use to encrypt data in a 32-bit block (the initial number of the block including the entry time stamp) in the initial data portion of the block and the unique disk key generated in step S1307.

In step S1313, the cryptographic block 150 encrypts the block data generated in step S1311 with a block key. It should be recalled that, as mentioned above, the cryptographic unit 150 encrypts bytes from (m + 1) to the last byte of the data block. The encryption algorithm used in this case is, for example, DES (data encryption standard) defined in FIPS 46-2.

In step S1314, the recording / reproducing apparatus writes the encrypted block data to the storage medium. At step S1315, it determines whether all data is recorded. If the result of the determination is that all the data has been recorded, the recorder / player exits the recording procedure. If not, the recording / reproducing apparatus returns to step S1308, where it processes the remaining data.

[Cryptography for reproducing data in a system with which recorded data must be compatible]

The following is a description of the decryption of the encrypted content recorded on the storage medium, as described in the previous section, with reference to the flowchart in FIG. 15 and the graphic diagram in FIG. 16.

First, a description is given with reference to the flowchart of FIG. 15. The recording / reproducing apparatus 1500 reads a disc identifier from a disc 1520 and a master key from its own memory. As follows from the preceding description of the data recording procedure, the disc identifier is unique disc identification information recorded on the disc. Alternatively, when no disc identifier is recorded, the recording / reproducing apparatus 1500 generates a disc identifier and writes it to the disc. The master key 1501 is a private key stored in the recording / reproducing device.

Then, the recording / reproducing apparatus 1500 generates a unique disc key from the disc identifier and the master key (as shown at 1503) as follows. The data generated by bitwise combining the master key and the disk identifier is entered, for example, in the SHA-1 hash function defined in FIPS 180-1, and only the required output signal length of 160 bits obtained from the calculation of the hash function is used as a unique drive key. As an alternative solution, as a unique disk key, the result of entering the main key and disk identifier into a hash function based on the block encryption function is used.

Then, the recording / reproducing apparatus 1500 reads from the disc a key 1504 recorded in accordance with the data to be recorded, and generates a unique title key 1505 from the title key 1504 and the unique disk key. A unique title key 1505 can also be generated using the SHA-1 hash function or a hash function based on the block encryption function.

As mentioned above, a unique drive key is generated from the master key and drive ID, and a unique cover key is generated from a unique drive key and cover key. However, a unique title key can be generated directly from the master key and disk identifier without generating a unique disk key, or a key equivalent to a unique title key can be generated from the master key and disk identifier without using a title key.

Then, the recording / reproducing apparatus 1500 reads the block data one after the other from the encrypted contents 1507 stored on the disk, separates the initial block number, forming four bytes in the initial part of the block data, using the selector 1508, and generates a block key using the processing operation performed also to generate a unique drive key.

A block key can be generated as described in the previous part with reference to FIG. That is, a block key of 64 bits can be generated from a seed of 32 bits and a unique title key of 64 bits.

Above was a description of examples of generating a block key in which a unique disk key, a unique title key, and a block key were generated. However, a block key can be generated from a master key, a disk identifier, a title key, and a block starting number for each block without generating a unique disk key and a unique title key.

When the block key is created, the block encrypted data is decrypted using the block key (as shown at 1509) and output as decrypted data through the selector 1510. It should be noted that the encrypted data includes an entry time stamp attached to each of the transport packets included in transport stream, and the stream is processed based on the timestamp of the entry using the above processor 300 TS. After that, the data can be used, for example, to play back images or music.

As indicated above, content encrypted in blocks and recorded on a storage medium can be decrypted for playback in blocks using a block key generated from an initial number including an entry timestamp.

The following is a sequence of operations performed for decrypting data and playback, with reference to the graphic diagram shown in Fig.16. In step S1601 of FIG. 16, the recording / reproducing apparatus reads the disc identifier from the disc and the master key from its own memory. In step S1602, the disc identifier and the master key are used to generate a unique disc key.

Then, in step S1603, the recording / reproducing device reads the title key from the data to be read from the disc. In step S1604, the recording / reproducing apparatus generates a unique title key from the title key and the unique disc key. Then, in step S1605, the recording / reproducing device reads the encrypted block data from the disk. In step S1606, the recording / reproducing device generates a block key from the 4 byte starting number of the block in the initial part of the block data and the unique header key generated in step S1604.

Then, in step S1607, the encrypted data is decrypted using the block key. In step S1608, it is determined whether the recording / reproducing device has read all the data. If it reads all the data, the recorder / player exits the decryption procedure. If not, the recording / reproducing apparatus returns to step S1605, where it reads the remaining data.

[Data encryption in a system with which recorded data should not be compatible]

The following is a description with reference to the flowchart of FIG. 17 and the flowchart of FIG. 18, explaining a data recording procedure in a system with which recorded data should not be compatible, namely in a system in which a storage medium having recorded on data using one recording / reproducing device cannot be reproduced in another recording / reproducing device, i.e. in a system in which the recorded data can only be read by the recording / reproducing device with which the data were recorded on the storage medium.

The following is a description with reference to the flowchart of FIG. 17 and then a description of the flow of operations with reference to the flowchart of FIG. 18.

In step S1801 of FIG. 18, the recording / reproducing device 1700 (see FIG. 17) generates a unique device key that is unique to the recording / reproducing device itself.

As shown in FIG. 17, a unique device key is generated either from a large integrated circuit key, or from a device key, or from a media key, or from a drive key, or based on a combination of any of these keys. The key of the large integrated circuit is the key stored in the large integrated circuit during the manufacture of the large integrated circuit included in the cryptographic unit 150 (see FIG. 1). A device key is a key set in accordance with a device, namely, a recording / reproducing device, and stored in a memory element such as flash memory, EEPROM or the like. during the manufacture of the recording / reproducing device. A media key is a key set for a storage medium that stores information and is stored on the storage medium. A drive key is a key assigned to a drive unit for a storage medium such as a DVD or the like.

In this embodiment, a unique device key is generated either from a large integrated circuit key, or from a device key, or from a media key, or from a drive key, or based on a combination of any of these keys.

The generation of a unique device key, for example, from a large integrated circuit key and a device key is described below with reference to FIG. 19, which shows by way of example the operations performed in the large integrated cryptographic circuit 1900, which is the cryptographic unit 150 in FIG. 1, executed , for example, in the form of a large integrated circuit.

The large integrated cryptographic circuit 1900 contains a memory 1901 for a key of a large integrated circuit that stores a key of a large integrated circuit common to many large integrated cryptographic circuits (therefore common to many recording / reproducing devices). In particular, the same key is stored in large integrated circuits of one manufactured batch. The common key of a large integrated circuit may be stored in all large integrated cryptographic schemes, or the shared key may be stored in each group of some large integrated cryptographic schemes. For how many large integrated circuits the common key of a large integrated circuit must be common, it can be determined based, for example, on the cost of manufacturing a large integrated cryptographic circuit.

The large integrated cryptographic circuit 1900 contains a key generator that reads the key of the large integrated circuit from the memory 1901 and simultaneously reads the key of the device 1910, for example, from the ROM in the recording / reproducing device as an external element of the cryptographic large integrated circuit 1900 via the bus, and generates a unique key devices using the key generation function to the key of the large integrated circuit and the device key.

It should be noted that as a key generation function, a one-way function can be used with which you can easily calculate a unique device key based on the keys of a large integrated circuit and device, but you cannot calculate the keys of a large integrated circuit and device. In particular, by using a combination of a large integrated circuit key and a device key entered into a one-way function, such as, for example, the SHA-1 hash function defined in FIPS 180-1, the unique device key generator 1902 calculates a hash function to generate a unique device key. A unique device key can be generated using a one-way function using the DES defined in FIPS 46-2 or the Triple-DES defined in FIPS 46-3 and encrypted the device key with a larger integrated circuit key.

The block key is generated from the unique key of the device thus generated and the starting number of the block as additional data to the content data, encryption or decryption is performed using the block key generated in this way to write or read encrypted content to / from the information carrier 1920.

For encryption and decryption of content, you can use DES (data encryption standard) defined in FIPS 46-2, or the like.

FIG. 19 shows an example of generating a unique device key from a large integrated circuit key and a device key. However, if the storage medium has a fixed-size media key, or if the drive for the storage medium has a fixed-size drive key, then the media key and drive key can be used to generate a unique device key.

FIG. 20 shows an example of generating a unique device key from all keys, including a media key and a drive key, in addition to a large integrated circuit key and a device key. In FIG. Figure 20 shows an example of generating a unique device key using the DIM (Data Integrity Mechanism) defined in ISO / IEC 9797.

The encryption unit 2001 encrypts the large integrated circuit key with the device key and provides the encrypted large integrated circuit key to the arithmetic unit 2004. The arithmetic unit 2004 performs an exclusive OR operation with the output of the encryption unit 2001 and the media key and provides the result of the exclusive OR operation to the encryption unit 2002. The encryption unit 2002 encrypts the output of the arithmetic unit 2004 with a large integrated circuit key and outputs the data to the arithmetic unit 2005. The arithmetic unit 2005 performs an exclusive OR operation with the output of the encryption unit 2002 and the drive key and outputs the data to the encryption unit 2003. The encryption unit 2003 encrypts the output of the arithmetic unit 2005 with a large integrated circuit key and provides the encryption result as a unique device key.

The following is a continuation of the description of the data recording procedure with reference to FIG. In step S1801, a unique device key is generated from a large integrated circuit key, a device key, a media key or a drive key, or based on a combination of any of these keys.

In step S1802, the recording / reproducing apparatus receives the encoded content data to be recorded in the form of TS packets. In step S1803, the TS processor 300 attaches an entry time stamp to each TS packet, which indicates the time at which each TS packet was received. Alternatively, the TS processor 300 attaches to each TS packet a combination of copy control information, entry timestamps, and other information. Then, in step S1804, the TS packets, each of which has an entry time stamp attached thereto, are received one by one and it is checked whether X (for example, X = 32) TS packets constitute one block or identification data indicating that that the last TS packet has been accepted. If any of the above conditions is met, the recording / reproducing device places TS packets or TS packets up to the last TS packet adjacent to each other in step S1805 X to form one data block.

Then, in step S1806, the cryptographic unit 150 generates a block key, which is the key for encrypting the data of the block, from 32 bits (the initial number, including the entry time stamp) in the initial part of the block data and the unique device key generated in step S1801.

In step S1807, the block data generated in step S1805 is encrypted using a block key. It should be noted that, as mentioned above, are encrypted from (m + 1) bytes to the last byte of the block data. The encryption algorithm used for this purpose is, for example, DES (data encryption standard) defined in FIPS 46-2.

In step S1808, the recording / reproducing apparatus writes the encrypted block data to the storage medium. At step S1809, it is determined whether or not all data is recorded. If all the data is recorded, the recorder / player exits the data recording procedure. If not all data is recorded, then the recording / reproducing apparatus returns to step S1802, where it processes the remaining data.

[Encryption of data to be reproduced in a system with which recorded data should not be compatible]

The following is a description of the reproduction or reading of data recorded in this way with reference to the flowchart of FIG. 21 and the graphical diagram of FIG. 22.

The description is made with reference to the flowchart of FIG. 21, and then to the flowchart of FIG. 22.

First, in step S2201 of FIG. 22, the recording / reproducing device 2100 (see FIG. 21) generates a device key unique to itself.

As shown in FIG. 21, a unique device key is generated from a large integrated circuit key, a device key, a media key, and a drive key, or based on a combination of any of these keys (as shown at 2101). As indicated above, the key of the large integrated circuit is the key stored in the large integrated circuit during the manufacture of the large integrated circuit included in the cryptographic unit 150 (see FIGS. 1 and 2), the device key is a key set in accordance with the device, namely a recording / reproducing device, and stored in a memory element such as flash memory, EEPROM or the like. during manufacture of the recording / reproducing apparatus, the media key is a key set for the information medium on which the contents are recorded and stored in the information medium, and the drive key is a key assigned to the drive unit for the information medium such as DVD or the like.

Then, in step S2202, the recording / reproducing apparatus decrypts the block data encrypted with the block key (as shown at 2105 in FIG. 21), determines in step S2205 whether or not all data has been read. If all the data has been read, the recorder / player exits the reading procedure. If not, the recorder / player returns to step S2202, where it reads the remaining data.

It should be noted that in the playback procedure, the first four bytes of the starting number of the block in the initial part of the block data in the encrypted content 2103 stored on the storage medium 2120 are also separated by the selector 2104, while the bytes from the first to m, which are to be encrypted, are not decrypted , however, bytes are combined together in the 2106 selector and fed to them by the output. The decrypted data contains an entry time stamp attached to each of the packets and indicating the time at which it was received at the input, and thereby can be normally reproduced by processing by the indicated processor TS.

As indicated above, according to the present invention, the content is encrypted with a block key, which varies depending on the timestamp of the entry, which in turn changes depending on the time of reception of the first packet data block TS. Thus, even if an encrypted block key for certain content is at the disposal of an unlicensed user, the rest of the content remains protected regardless of leakage. If you use one encryption key to encrypt all content, as is the case in conventional systems, data encryption using a fixed key can lead to the following results. Namely, if an unlicensed user trying to illegally copy the content gets a combination of unencrypted or open content and content derived from encrypting this content with a data key, it is quite possible to analyze the data key using the so-called linear or differential cryptanalysis (for disclosing the content), whereby all content encrypted with a data key can be decrypted for illegal copying. However, according to the present invention, since the encryption key is different for different blocks, such illegal copying becomes almost impossible.

According to this invention, since the amount of data encrypted with one encryption key is only one block that contains as little data as possible, it is very difficult to use the so-called linear or differential cryptanalysis to obtain the key with which the data is encrypted.

In addition, according to this invention, since the encryption key is generated based on the timestamp attached as additional data to the main data, it does not need to be written again, for example, in the header of the data sector of the storage medium, even if it is changed from one block to another. Thus, an additional recording zone is not required, and there is no need to read and write the encryption key for each block when writing and reading data.

[Encryption of data for recording in a system in which a restriction for a playback device can be set]

The above structure of the recording / reproducing apparatus according to the present invention provides for generating a block spike from a master key and reading the recorded data by a recording / reproducing apparatus having a common master key. However, in some cases, it is desirable that only the recording / reproducing apparatus recording the special data can read or reproduce this data. A description of such a limitation for a playback device is provided below.

The following is a description of a system in which a storage medium 195 is removably mounted in a recording / reproducing apparatus described above with reference to FIGS. 1 and 2, and which can also be used in another recording / reproducing apparatus. That is, when data is recorded on the storage medium 195, it can be installed in another recording / reproducing device, regardless of whether or not it can play the storage medium on which the data is recorded.

The following is a description of the encryption of data for recording in such a system with reference to the flowcharts shown in FIGS. 23 and 24, and to the graphic diagram shown in FIG. 25. The storage medium used in this case is an optical disk. In this embodiment, the disk identifier is used as unique media information for a data encryption key and to prevent bitwise copying of data from the storage medium.

A description of data encryption using a cryptographic unit 150 is provided with reference to the flowcharts of FIGS. 23 and 24.

The recording / reproducing device 2300 reads a master key 2301, a device identifier 2331 for identifying a recording / reproducing device, and a unique device key 2332 from its own memory 180 (see FIGS. 1 and 2). The master key 2301 is a private key stored in a licensed recording / reproducing device and shared by a plurality of recording / reproducing devices, namely, the entire system. A device identifier is an identifier for a recording / reproducing device 2300, such as a sequence number or the like, which is previously recorded in the recording / reproducing device. The device unique key is a private key unique to the recording / reproducing device 2300 and predefined with a change from one recording / reproducing device to another. These keys are pre-recorded in the device 2300 recording / playback.

The recording / reproducing apparatus 2300 checks whether the disc identifier 2303 is already recorded as identification information on the information medium 2320, which is, for example, an optical disc. If the disc identifier 2303 is recorded, then the recording / reproducing apparatus 2300 reads the disc identifier 2303 (as in FIG. 23). If not, then the cryptographic unit 150 generates an identifier 2401 of the disk randomly or using the specified method of generating random numbers and writes it to an optical disk (as shown in Fig.24). Only one disc identifier 2303 is provided for each disc, so that the disc identifier can be recorded in the input area or the like. optical disk.

Then, the recording / reproducing device 2300 generates a unique disc key from the master key and the disc identifier (as shown at 2302). In particular, a unique disk key is generated as follows. Namely, as shown in FIG. 26, the result of substituting the master key and disk identifier in a hash function based on the block encryption function is used as a unique device key (method 1). As an alternative solution, the required data length of the output signal of 160 bits obtained by substituting in the SHA-1 hash function defined in FIPS 180-1, the data generated by bitwise combination of the master key and disk identifier is used as a unique disk key (method 2).

Then, a cover key is generated, which is a unique key for each record, for example, according to a random law or using the specified method of generating random numbers, using a cryptographic unit 150 (as indicated by 2304), and is recorded on the disk 2320.

In addition, a flag is set indicating which title corresponds to data that can only be played back by a recording / reproducing device that recorded data (when a restriction is set for the playback device), or data that can also be played back in another recording / reproducing device (when not set restriction for the playback device), i.e. a restriction flag (as shown at 2333), and is written to the disc (as shown at 2335). In addition, the device identifier 2334 is retrieved as identification information (as shown at 2331) and recorded on the disk 2320 (as shown at 2334).

The disk contains a data management file that stores information about which titles are generated from the data and where the data is from, and in which the title key 2305, a playback device restriction flag 2335, and a device identifier 2334 can be stored.

Then a unique title key is generated either based on a combination of a unique disk key, title key and device identifier, or based on a combination of a unique disk key, title key and a unique device key.

Namely, in the case when there is no restriction for the playback device, a unique title key is generated from the unique disk key, title key and device identifier. On the other hand, when a restriction is set for the reproducing device, a unique title key is generated from a unique disk key, title key and a unique device key.

In particular, a unique title key is generated as in Example 1 or Example 2 shown in FIG. 28. In Example 1, a unique disk key and device identifier (when the restriction for the playback device is not set) or a unique device key (when the restriction for the playback device is set) is substituted into a hash function based on the block encryption function, and the substitution result is used as a unique title the key. In Example 2, the data generated by bitwise combining the master key, disk identifier, and device identifier (when the restriction for the playback device is not set) or a unique device key (when the restriction for the playback device is set) is substituted into the SHA-1 hash function defined in FIPS 180-1, and 160-bit output obtained from the substitution is used as a unique title key.

As indicated above, a unique drive key is generated from the master key and the drive identifier, and then a unique title key is generated from the unique drive key, title key and device identifier, or from the title key and the unique device key. However, it should be noted that a unique title key can be generated directly from the master key, disk identifier, title key and device identifier or a unique device key without using a unique disk key, or a key equivalent to a unique title key can be generated from the master key, disk identifier and device identifier (when the restriction for the playback device is not set) or from a unique device key (when the restriction for oystva playing) without using the title key.

For example, if one of the transmission formats defined in the above DTCP standard is used, the data is transmitted in some cases in the form of MPEG-2 TS packets. When, for example, a set-top box that has received satellite broadcasts transmits the broadcast to the DTCP recorder, this is desirable since there is no need to convert the data that the set-top box must transmit on the IEEE 1394 serial bus, as well as TS MPEG-2 packets transmitted over satellite broadcasting channel.

The recording / reproducing apparatus 2300 receives the content data to be recorded in the form of TS packets, and the TS processor 300 attaches an entry time stamp to each TS packet that contains information indicating the time at which the TS packet was received. It should be noted that, as indicated above, a combination of the entry timestamp, copy control information and other information can be attached as the starting number of the block, which is information unique to the block data.

The number X (for example, X = 32) of the TS packets, to each of which an entry time stamp is attached, is arranged adjacent to each other to form one data block (block data), as shown at the top of FIG. 5, and generate a block key, designed to encrypt data in a block, from the initial number of blocks, including a 32-bit entry timestamp and obtained by separating 1-4 bytes in the initial part of the block data transmitted as encrypted data (in selector 2308) and the previously generated unique title key (as shown at 2307), as shown in the lower parts of FIGS. 23 and 24. A block key can be generated using the method described above with reference to FIG.

Above was a description of examples of generating a unique disk key, unique title key and block key. However, it should be noted that the block key can be generated from the master key, disk identifier, title key, block starting number and device identifier (when the restriction for the playback device is not set) or a unique device key (when the restriction for the playback device is set) without generating a unique key drive and unique title key.

The block key generated in this way is used to encrypt the block data. As shown in the lower parts of Figs. 23 and 24, bytes 1-m (for example, m = 8) in the initial part of the block data, including the initial number of the block, are separated (in the selector 2308) to exclude from encryption, and bytes from (m + 1) until the last byte is encrypted (as shown at 2309). It should be noted that m bytes not subject to encryption include bytes 1-4 as the starting number of the block. The byte (m + 1) and subsequent data bytes of the block, separated by the selector 2308, are encrypted (as shown by 2309) in accordance with the encryption algorithm specified in the cryptographic unit 150. The encryption algorithm may be, for example, DES (data encryption standard) defined in FIPS 46-2.

When the block length (input / output data size) in the encryption algorithm used is 8 bytes, as in DES, then all the block data, including bytes (m + 1) and subsequent bytes without a remainder, can be encrypted at X = 32 and m , multiple of 8.

Namely, in the case of recording TS packets in one block X, the size of the input / output data of the encryption algorithm is L bytes, and n is an arbitrary natural number, then no remainder needs to be processed by choosing X, m and L so that 192 * X = m + n * L.

Encrypted bytes (m + 1) and subsequent bytes of block data are combined with unencrypted bytes 1-4 of block data using a selector 2310 and stored as encrypted content 2312 on the storage medium 1120.

Using the above operations, the content is encrypted block by block with a block key generated from the initial number of the block, including the timestamp of the entry and stored on the storage medium. The block key is generated from the device identifier when the restriction for the playback device is not set, or from the unique key of the device when the restriction for the playback device is set. In the case where a restriction is set for the playback device, this encrypted data can only be read or reproduced using the device that recorded this data.

Namely, when the restriction for the reproducing device is not set, the block key, which is the key to use for encrypting the block data, is generated from the data including the device identifier, and the device identifier is stored on the storage medium. Therefore, the reproducing device that intends to reproduce the storage medium obtains a device identifier from the storage medium installed therein, and thus generates a similar block key. Thus, the block data can be decrypted. However, in the case where a restriction is set for the reproducing device, a block key, which is a key for encrypting the block data, is generated from data including a unique device key. Since this unique device key is a private key that changes from one device to another, it cannot be obtained by another device. In the case when the block data is encrypted to be stored on the storage medium, data is not recorded on the storage medium having a unique device key stored on it. Therefore, since the same unique device key cannot be obtained even if the storage medium having the encrypted block data stored on it is installed in another playback device, an encryption key for decrypting the data block cannot be generated, and thus the block data cannot be decrypted for playback. It should be noted that playback operations will be further described below.

Below, with reference to FIG. 25, a description will be made of the sequence of operations performed in the TS processor 300 for attaching an entry time stamp, and the sequence of operations performed for encryption in the cryptographic unit 150 for recording data. In step S2501 of FIG. 25, the recording / reproducing device reads a master key, a device identifier that identifies the recording / reproducing device, and a unique device key stored in its own memory 180.

In step S2502, the recording / reproducing apparatus checks whether the disc identifier is already recorded as the identification information on the storage medium. If it is determined that it has been recorded, the recorder / player reads out the disc identifier in step S2503. If not, the recording / reproducing apparatus generates a disc identifier randomly or using a predetermined method and writes it to the disc in step S2504. Then, in step S2505, the recording / reproducing apparatus generates a unique disc key from the master key and the disc identifier. A unique drive key is generated using, for example, the SHA-1 function defined in FIPS 180-1, or a hash function based on the block encryption function, as mentioned above.

In step S2506, the recording / reproducing apparatus retrieves a title key unique to each record, a restriction flag of the reproducing apparatus, and a device identifier, which is identification information for the apparatus, and writes them to a disc. Then, in step S2507, the recording / reproducing device generates a unique title key from the unique disc key, title key and device identifier (when the restriction for the playback device is not set) or the unique device key (when the restriction for the playback device is set).

On Fig shows the sequence of operations performed when generating a unique title key. At step S2701, the cryptographic unit 150 determines whether a restriction on the playback device should be set based on instruction data entered by the user of the recording / reproducing device or restricting the use of information attached to the content.

If the result of the determination made in step S2701 is “No”, namely, if there is no restriction for the playback device, the recording / reproducing device proceeds to step S2702, where it generates a unique title key from the unique disc key, title key and identifier devices.

If the result of the determination made in step S2701 is “Yes”, namely, if a restriction is set for the reproducing apparatus, the recording / reproducing apparatus proceeds to step S2703, where it generates a unique title key from a unique disc key, a title key and a unique key devices using the SHA-1 hash function or a hash function based on the block encryption function.

In step S2508, the recording / reproducing apparatus receives the data to be encrypted to be encoded of the content data in the form of TS packets. In step S2509, the TS processor 300 attaches an entry time stamp to each TS packet containing information about the time at which the packet was received. Alternatively, the TS processor 300 attaches to each TS packet a combination of copy control information, entry timestamps, and other information. Then, in step S2510, the recording / reproducing apparatus receives TS packets one after the other, an entry time stamp is attached to each of them, and determines whether the number X (for example, X = 32) of TS packets forming one block or identification data indicating that the last packet has been accepted. When one of the above conditions is met, the recorder / player proceeds to step S2511, where it locates X TS packets or TS packets up to the last adjacent to each other to form one data block.

Then, in step S2512, the cryptographic unit 150 generates a block key, which is the key for encrypting data, from 32 bits (the initial number of the block including the entry time stamp) in the initial data portion of the block and the unique title key generated in step S2507.

In step S2513, the block data generated in step S2511 is encrypted with a block key. As mentioned above, bytes (m + 1) to the last byte in the block data are encrypted. The encryption algorithm is, for example, DES (data encryption standard) defined in FIPS 46-2.

In step S2514, the encrypted block data is recorded on the storage medium. When all the block data is recorded, the recorder / player exits the recording procedure. If not, the recorder / player returns to step S2508, where it processes the remaining data.

[Decryption for reproducing recorded data in a system in which a restriction for a reproducing apparatus can be set]

Below, with reference to the flowchart of FIG. 29 and the graphical diagram of FIG. 30 describes operations performed for decryption to reproduce encrypted content recorded on a storage medium as described above.

First, a description is given with reference to the flowchart of FIG. 29. The recording / reproducing device 2900 reads the disc identifier 2902 from the disc 2920, the master key 2901, the device identifier 2931, and the unique key of the device 2932 from its own memory. As follows from the previous description of the recording procedure, the disc identifier is an identifier unique to the disc and recorded on the disc. If it is not written to a disc, then it is generated by the recorder / player and written to the disc. The master key 2901 is a private key stored in the licensed recording / reproducing device 2900, the device identifier is an identifier unique to the recording / reproducing device 2900, and the unique device key is a private key unique to the recording / reproducing device.

Then, the recording / reproducing apparatus 2900 generates a unique disc key from the disc identifier and the master key (as shown at 2903). A unique disk key is generated by substituting data generated by bitwise combining the master key and the disk identifier, for example, into the SHA-1 hash function defined in FIPS 180-1, and using only the required data length 160 bit output resulting from the substitution , or a unique disk key is generated using the result of substituting the master key and disk identifier in a hash function based on the block encryption function.

Then, the recording / reproducing apparatus reads the title key 2905, recorded accordingly in the data to be read from the disc, and then the identifier 2935 of the recording / reproducing apparatus that recorded the data, and the reproducing apparatus restriction flag 2933 set in accordance with the data. If the playback device restriction information indicated by the flag 2933 indicates that “The playback device restriction is set” and “The device identifier 2934 read from the storage medium matches the identifier 2931 of the playback device itself” or “The playback device restriction is not set”, then the data can reproduce. If the restriction information of the playback device indicated by the flag 2933 indicates that “Restriction of the playback device is set” and “The device identifier 2934 read from the storage medium does not coincide with the identifier 2931 of the reproducing device itself,” the data cannot be reproduced.

The reason that the data cannot be reproduced is that the block key for decrypting the data cannot be generated, since the data was encrypted with the block key generated from the device’s unique key for the data recording / reproducing device, while the recording device / playbacks other than the recording / reproducing device that recorded the data do not have the same unique device key.

If it is possible to reproduce data, a unique title key is generated from a unique disk key, title key, device identifier. When the restriction of the playback device is set, the unique title key is generated from the unique disk key, title key and the unique key of the playback device itself. To generate a unique title key, you can use the SHA-1 hash function or a hash function based on the block encryption function.

As indicated above, a unique disk key is generated from the master key and the disk identifier, and a unique title key is generated based on a combination of a unique disk key, title key and a device identifier, or based on a combination of a title key and a unique device key. However, a unique title key can be generated directly from the master key, disk identifier, title key and device identifier or a unique device key without using a unique disk key, or a key equivalent to a unique title key can be generated from the master key, disk identifier, and device identifier (when the restriction of the playback device is not set) or a unique key of the device (when the restriction of the playback device is set), without h using the title key.

Then, the recording / reproducing device reads the block data one by one from the encrypted data 2912 stored on the disk, separates the initial block number formed by four bytes in the initial part of the block data in the selector 2910, and generates a block key from the unique title key and the block starting number.

A block key can be generated as described above with respect to FIG. That is, a block key of 64 bits can be generated from an initial block number of 32 bits and a unique title key of 54 bits.

The above is a description of examples of generating a unique disk key, a unique title key, and a block key. However, it should be noted that a block key can be generated for each block from the master key, disk identifier, title key, initial block number and device identifier (when the playback device restriction is not set) or from the unique device key (when the playback device restriction is set) without generating unique drive key and unique title key.

The encrypted data of the block is decrypted by the block key thus created (as shown at 2909) and is output as decrypted data through the 2908 selector. It should be noted that the decrypted data includes an entry time stamp attached to each transport packet included in the transport stream, and the stream is processed based on the entry timestamp in the above processor 300 TS. After that, the data can be used, for example, to play back images or music.

Thus, the content encrypted in blocks on the storage medium can be decrypted for playback using the block key generated from the initial number of the block, including the entry timestamp, in blocks.

The following is a description of the sequence of operations performed during data decryption and reproduction, with reference to the graphic diagram shown in Fig. 30. In step S3001 of FIG. 30, the recording / reproducing device reads the disc identifier from the disc and the master key, the device identifier and the unique device key from its own memory. In step S3002, the recording / reproducing apparatus generates a unique disc key from the disc identifier and the master key.

Then, in step S3003, the recording / reproducing apparatus reads a title key for data to be read from the disc, the identifier of the recording / reproducing apparatus that has recorded the data, and the restriction flag of the reproducing apparatus set in accordance with the data.

Then, in step S3004, the recording / reproducing apparatus determines whether it is possible to reproduce data to be read. The decision procedure is shown in FIG. At step S3101 in FIG. 31, a decision is made whether the restriction information of the playback device indicated by the read restriction flag of the playback device means that “a restriction for the playback device is set”. If yes, then in step S3102, the recording / reproducing apparatus determines whether the identifier of the device read from the storage medium matches an identifier unique to the reproducing apparatus itself. If so, the recorder / player decides that the data can be reproduced. When it is decided in step S3101 that the restriction of the playback device is not set, the recording / reproducing device also decides that the data can be reproduced. If the information of the restriction of the playback device indicated by the read limit flag of the playback device means that the “Restriction of the playback device is set "and the device identifier read from the storage medium does not match the identifier of the playback device itself," the device / Playback decides that the data can not be played.

Then, in step S3005, the recording / reproducing device generates a unique title key. Below is a detailed description of the sequence of operations performed when generating a unique title key, with reference to Fig. In step S3201 in FIG. 32, the cryptographic unit 150 determines whether or not to set the limit of the playback device based on the restriction flag of the playback device read from the disk.

If the decision "No" is made in step S3201, that is, if the decision is that the restriction of the playback device should not be set, then the recording / reproducing device proceeds to step S3203, where it generates a unique title key from a unique disk key , title key and unique key of the playback device itself. A unique cover key is generated using the SHA-1 hash function or a hash function based on the block encryption function.

Then, in step S3007, the recording / reproducing device generates a block key from the initial number of the block including four bytes in the initial part of the block data and the unique title key generated in step S3005.

Then, in step S3008, the recording / reproducing apparatus decrypts the block data encrypted with the block key, and determines in step S3009 whether all the data has been read. If all the data has been read, the recorder / player exits the procedure. If not, the recording / reproducing apparatus returns to step S3006, where it reads the remaining data.

As indicated above, when the restriction of the playback device is not set, the recording / reproducing device can generate a block key from the device identifier. In the case where the restriction of the playback device is set, the recording / reproducing device may generate a block key from the unique key of the device. In any of these cases, the recording / reproducing device can encrypt the contents in blocks and write encrypted data to the storage medium. To reproduce data from a storage medium, data encrypted using a unique device key can only be reproduced using the device that recorded this data. In the case where the restriction of the playback device is not established, any recording / reproducing device other than the device that recorded the data can generate a block key from the identifier of the device recorded on the disc, and thereby decrypt and reproduce the data.

[Copy control when recording data]

To protect the interests of the copyright owner, a licensed device must manage the copying of content.

That is, when writing content to a storage medium, it is necessary to check whether or not to copy the contents, and only write data that can be copied. In order to reproduce content from the storage medium and output data, it is also necessary to protect the content from illegal copying in the future.

The following is a description of the operations of the recording / reproducing apparatus shown in FIGS. 1 and 2 for recording or reproducing such content while controlling copying with reference to the graphic circuits shown in FIGS. 33 and 34.

First, to record external content from digital signals to a storage medium, write operations are illustrated, illustrated in the diagram shown in FIG. 33A. The following is an example of a description of the operations of FIG. 33A with respect to the recording / reproducing apparatus 100 shown in FIG. The input / output interface 120 receives, in step S3301, the contents of the digital signals (digital content) via an IEEE 1394 serial bus or the like, and the recording / reproducing apparatus proceeds to step S3302.

In step S3302, the input / output interface 120 determines whether the transmitted digital content can be copied. That is, in the case where the content received by the input / output interface 120 is not encrypted (for example, open or unencrypted content is transmitted via the input / output interface 120 without applying the above DTCP standard), it is decided that the content can be copied.

Assume in this case that the recording / reproducing apparatus 100 is a DTCP compliant device and records data in accordance with the DTCP standard. The DTCP standard is indicated by a 2-bit copy mode indicator (EMI) as copy control information. When the copy mode indicator is 00V (B indicates that the preceding value is a binary number), this means that the contents can be freely copied (free copy). When the copy mode indicator is 01V, this means that the contents cannot be copied beyond the specified limit (limited copying). In addition, when the copy mode indicator is 10V, this means that the contents can be copied once (single copy). When the copy mode indicator is 11V, it means that the contents are prohibited for copying (forbidden copying).

The signals supplied to the input / output interface 120 of the recording / reproducing apparatus 100 comprise a copy mode indicator. When the copy mode indicator means “free copy” or “single copy”, it is decided that the contents can be copied. On the other hand, when the copy mode indicator means “limited copying” or “forbidden copying”, it is decided that the contents cannot be copied.

If the result of the decision in step S3302 is that the content cannot be copied, then the recording / reproducing apparatus 100 skips steps S3303-3305 and leaves the recording procedure. Therefore, in this case, the content is not copied to the storage medium 195.

If the result of the decision in step S3302 is that the content can be copied, then the recording / reproducing apparatus 100 proceeds to step S3303. Then, in steps S3303 to 3305, the recording / reproducing apparatus 100 sequentially performs operations similar to those in steps S302, 303, and 304 of FIG. 3A. That is, the TS processor 300 attaches an entry time stamp to each TS packet included in the transport stream, the cryptographic unit 150 encrypts the data, and the encrypted data from the cryptographic unit 150 is recorded on the information medium 195. Here, the recording / reproducing apparatus exits the recording procedure.

It should be noted that the copy mode indicator is included in the digital signals transmitted to the input / output interface 120. In the case where digital content is recorded on the storage medium 195, a copy mode indicator or information indicating a copy control status similar to a copy mode indicator (for example, included copy control information defined by the DTCP standard or the like) is recorded together with the digital content .

Typically, information indicating “one-time copying” is converted to “limited copying” and recorded to prohibit copying beyond a specified limit.

The recording / reproducing apparatus according to the present invention records copy control information, such as a copy mode indicator (EMI), included copy control information (CCI), i.e. attached to TS packets. That is, as in examples 2 and 3 in FIG. 10, 32 bits are added to each TS packet, including 24-30 bits of the timestamp of the input and copy control information, as shown in FIG. 5.

To record external content from analog signals to a storage medium, a recording procedure is presented, represented by the graphic circuit in FIG. 33B. The following is a description of the recording procedure shown in FIG. 33B. The content of the analog signals (analog content) is transmitted in step S3311 to the input / output interface 140. Then, the recording / reproducing apparatus proceeds to step S3312, where it determines whether the analog content can be copied.

At step S3312, a decision is made based on whether or not the signals received by the input / output interface 140 contain a Macrovision signal and a CGMS-A signal (copy quantity control system for analog signals). When recording VHS tape on a tape, the Macrovision signal is noise. If the Macrovision signal is included in the signals received by the input / output interface 140, then a decision is made that the analog content cannot be copied.

The CGMS-A signal is a CGMS signal used to control copying of digital signals, and is used to control copying of analog signals. He indicates that the contents can be freely copied or copied once or cannot be copied (free copying, single copying and forbidden copying).

Therefore, if the CGMS-A signal is included in the signal received by the input / output interface 140 and means “free copy” or “one-time copy”, then it is decided that the analog content can be copied. When the CGMS-A signal means “forbidden copying”, it is decided that the analog content cannot be copied.

In addition, when neither Macrovision nor the CGMS-A signal is included in the signals received by the input / output interface 140, it is decided that the analog content can be copied.

If it is decided in step S3312 that the analog content cannot be copied, then the recording / reproducing apparatus 100 jumps through steps S3313-3317 and leaves the recording procedure. Therefore, in this case, the content is not recorded on the storage medium 195.

If it is determined in step S3312 that the analog content can be copied, the recorder / player proceeds to step S3313. Then, in steps S3313-3317, operations similar to those performed in steps S322-326 of FIG. 3B are sequentially performed, the content is converted to digital content and then subjected to MPEG encoding, transport stream processing and encryption for recording to the storage medium are performed. Here, the recording / reproducing apparatus exits the recording procedure.

It should be noted that when the analog signals that are pleasing to the input / output interface 140 include the CGMS-A signal, the CGMS-A signal is also recorded on the storage medium when the analog content is recorded on the storage medium. Namely, the CGMS-A signal is recorded in place of copy control information or other information shown in FIG. 10. Typically, information indicating “one-time copying” is converted to “limited copying” to prevent copying beyond a predetermined limit. However, such a conversion is not performed provided that the system has a rule that the copy management information “one-time copy” should not be converted to “limited copy”, but should be understood as “limited copy”.

[Copy control when playing data]

Then, the content is read from the storage medium and transmitted as digital content to the output, as shown in the graphical diagram of FIG. 34A. The following is a description of the operations shown in FIG. 34A. First, steps S3401, 3402, and 3403 perform operations similar to those performed in steps S401, 402, and 403 of FIG. 4A, wherein the encrypted content read from the storage medium is decrypted using a cryptographic unit 150 and transport stream processing is performed. After performing this processing, digital content is transmitted to the input / output interface 120 via the bus 110.

In step S3404, the input / output interface 120 determines whether it is subsequently possible to copy the digital contents transferred thereto. Namely, in the case where the digital content transmitted to the input / output interface 120 does not include the copy mode indicator or information indicating the copy control status (copy control information) similar to the copy mode indicator, it is decided that the content can be copied to subsequent.

In the case where the digital content transmitted to the input / output interface 120 includes, for example, a copy mode indicator, namely, in a case where the copy mode indicator was recorded in accordance with the DTCP standard during data recording, and if the copy mode indicator (recorded indicator of the copy mode) means "free copying", it is also decided that the contents can be copied later. When the copy mode indicator indicates "limited copy", it is decided that the contents cannot be copied later.

It should be recalled that the usually recorded copy mode indicator does not mean “one-time copy” and “forbidden copy”, since the value of the copy-only indicator “one-time copy” is converted to “limited copy” during data recording, and digital content having the value of the copy mode indicator "forbidden copying" is not recorded on the storage medium. However, the conversion of the copy mode indicator may not be performed provided that the system has adopted the rule that the “one-time copy” copy control information should not be converted to “limited copy” for recording, but should be interpreted as “limited copy”.

If it is decided in step S3404 that the content can be copied subsequently, the input / output interface 120 proceeds to step S3405, where it transfers the digital content to the output and exits the playback procedure.

Thus, the input / output interface 120 performs mutual authentication with the communicating device in accordance with the DTCP standard. If the communicating device is legal (a DTCP compliant device), then the input / output interface 120 encrypts the digital content and transfers the data to the output.

Then, to reproduce the content from the storage medium and output the data in the form of analog content, reproduction is performed in accordance with the graphical diagram in FIG. 34B. The following is a description of the playback operations with reference to figv. In steps S3411-3415, operations similar to those performed in steps S421-425 of FIG. 4B are performed. Namely, the encrypted content is read and decrypted, processed by TS, MPEG decoding and digital-to-analog conversion. The analog content thus obtained is received by the input / output interface 140.

In step S3416, the input / output interface 140 decides whether the supplied content can be copied subsequently. Namely, in the case where copy control information recorded along with the content is not detected, a decision is made that the content can be copied later.

In the case where the copy mode indicator or copy control information was recorded during recording of the contents in accordance with, for example, the DTCP standard, and if the copy mode indicator or copy control information indicates “free copy”, it is decided that the content can be copied subsequently .

In the case where the copy mode indicator or control information indicates “limited copying”, or in the case where the rule is adopted in the system that the “one-time copy” copy control information should not be converted to “limited copying” for recording, but should be interpreted as “limited copying” and if the copy mode indicator or copy control information recorded under these conditions means “one-time copying”, it is decided that the contents cannot be feast later.

In addition, in the case where the analog content transmitted to the input / output interface 140 includes the CGMS-A signal, namely, in the case where the CGMS-A signal was recorded with the contents during the recording of the contents, and if the CGMS-A signal indicates "free copy", it is decided that the analog signal can be copied later. When the CGMS-A signal indicates “forbidden copying”, it is decided that the analog content cannot be copied subsequently.

If it is decided in step S3416 that the analog content can be copied subsequently, the input / output interface 140 proceeds to step S3417, where it outputs the analog signals received therein unchanged and leaves the playback procedure.

If it is decided in step S3416 that the analog content cannot be copied subsequently, the input / output interface 140 proceeds to step S3418, where it outputs the analog signals received therein in such a way that the content cannot be copied and exits playback procedures.

Namely, in the case where the copy control information, such as the recorded copy mode indicator, means “limited copy” as above (as an alternative solution, in the case where the rule is made in the system that the “one-time copy” copy control information is not should be converted to “limited copy” for recording, and should be understood as “limited copy”, and if copy control information such as the copy mode indicator recorded under these conditions x, means "one-time copy"), then further copying of the contents is prohibited.

Thus, the input / output interface 140 connects the Macrovision signal and the CGMS-A signal indicating “prohibited copying” to the analog content, and outputs the analog signal to the output. In the case where the signal CGMS-A means, for example, “forbidden copying”, the contents are prohibited for further copying. Thus, the input / output interface 140 modifies the CGMS-A signal into “forbidden copying” and outputs it together with the analog contents to the outside.

As indicated above, by controlling the copying of the contents during recording or reproduction of the contents, it is possible to prevent the copying of the contents outside the permitted range for the contents (illegal copying).

[Data processor structure]

It should be noted that the above sequence of operations can be performed using hardware or using software. Namely, the cryptographic unit 150 may be formed from one large integrated encryption / decryption circuit, and cryptography, namely the encryption / decryption performed by the cryptographic unit 150, may be performed by a general purpose computer or by a single-chip microcomputer executing the corresponding program. Similarly, the TS processor 300 may be replaced by software. To perform sequences of operations for processing a transport stream using software, a program including software is installed in a general-purpose computer, a single-chip microcomputer, or the like. On Fig shows an example of the structure of one embodiment of a computer in which a program is installed to perform a sequence of operations.

The program can be pre-recorded on the hard drive 3505 and in the ROM 3503 as a storage medium included in the computer. Alternatively, the program may be stored (recorded) temporarily or permanently on a removable storage medium 3510, such as a floppy disk, CD-ROM (read-only CD), MO (magneto-optical disk), DVD (digital universal disk) , magnetic disk, semiconductor memory, or the like. For such a removable storage medium 3510, so-called batch software may be provided.

It should be noted that the program can be installed on a computer from the above removable storage medium 3510, or transferred from a download site to a computer using a radio network via a digital broadcast satellite, or transferred to a computer via cable through a network such as a local area network , Internet or the like, the computer receives the program transmitted in this way using its communication unit 3508 and installs it on the built-in hard drive 3505.

As shown, the computer includes a central processor 3502. A central processor 3502 is connected to an input / output interface 3511 via a bus 3501. When the central processor 3502 receives instructions from a user input unit 3507, such as a keyboard, mouse, or the like, via an interface 3511 I / O, then it runs the program stored in ROM 3503.

Alternatively, the central processor 3502 loads into RAM 3504 to execute a program stored on a hard disk 3505, a program transmitted from a satellite or network, received by the communication unit 3508 and installed on the hard disk 3505, or a program read from a removable medium 3510 information installed in the drive 3509 and recorded on the hard drive 3505.

Thus, the central processing unit 3502 performs the operations shown in the above graphic diagrams, or the operations shown in the above flowcharts. The central processor 3502 outputs the results of these operations from an output unit 3506, such as a liquid crystal display (LCD) or loudspeaker, or transfers them from the communication unit 3508, or writes them to a hard disk 3505 via an input / output interface 3511, if necessary.

It should be noted that the operations or processes for describing a program that ensures that a computer performs various operations may not always be performed in that time sequence, as shown in the graphic diagrams, the program may contain operations that are executed in parallel or individually (for example, parallel processes or object processes).

A program can be executed by one computer or by a decentralized set of computers. In addition, the program may be a program that can be transferred to a remote computer for execution.

The above description of the present invention with reference to an example in which a cryptographic unit formed from a single-chip large integrated circuit encryption / decryption encrypts and decrypts the contents. However, it should be noted that the content encryption / decryption unit may be one software module, which is to be executed using, for example, the central processor 170 shown in FIGS. 1 and 2. Similarly, the operations of the TS processor 300 can be performed by one software module. using the central processor 170.

The above is a detailed description of the present invention in relation to specific embodiments of the invention. However, it is obvious that the options for implementation can be modified or changed by specialists in this field of technology, without going beyond the scope of this invention. Namely, since the invention is disclosed by way of examples, the embodiments should not be interpreted in a restrictive manner. This invention is essentially defined in the claims below.

Industrial applicability

The device and method for recording / reproducing information according to this invention, provide generating a block key for encrypting block data based on an entry time stamp that contains random data corresponding to the time at which each packet arrives. Thus, you can generate a unique key that changes from one block to another, use a different encryption key for each block, and thereby increase protection against cryptanalysis of data. In addition, by generating a block key based on the timestamp of the entry, it is not necessary to provide an area for storing an encryption key for each block in the storage medium, and thus it is possible to more effectively use the area for storing master data. Additionally, access to data other than the main data is not required during data recording or reproduction, and thereby data recording or reproduction can be performed more efficiently.

Claims (47)

1. A device for recording information on a storage medium containing transport stream processing means configured to attach an entry time stamp (ATS) to each of the individual transport packets included in the transport stream, cryptographic means configured to generate a block key for encrypting data blocks, including more than one transport packet, each of which has an attached timestamp, from the initial number of the block, which is additional information mation unique to the block data including an arrival time stamp, and encrypting each data block using the thus generated block key, and recording means capable of recording data encrypted using the encryption means on a recording medium. 2. The device according to claim 1, characterized in that the cryptographic means is configured to generate a block key for encrypting block data from the initial number of the block, which is additional information unique to the block data, including an entry time stamp attached to the first packet from the set transport packets included in the block data. 3. The device according to claim 1, characterized in that the cryptographic means is configured to generate a unique title key from the main key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to data to be recorded on the storage medium, and generating a block key from a unique title key and the starting number of the block. 4. The device according to claim 1, characterized in that the cryptographic means is configured to generate a disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to the data to be recorded on the information medium, and save them on the medium information. 5. The device according to claim 1, characterized in that the initial number of the block contains copy control information in addition to the entry time stamp. 6. The device according to claim 1, characterized in that the cryptographic tool is configured to encrypt with the block key only the data included in the block data, and exclude additional data from encryption in the initial zone and containing the initial number of the block. 7. The device according to claim 1, characterized in that the cryptographic means is configured to generate a unique title key from the master key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to data to be recorded on the storage medium, as well as using the unique title key generated in this way as a key for the encryption function, substitution of the initial about the number of blocks in the encryption function and issuing the result of the substitution as a block key. 8. The device according to claim 1, characterized in that the cryptographic means is configured to generate a unique title key from the main key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to data to be recorded on the storage medium, substituting the unique title key generated in this way and the starting number of the block into a one-way function and issuing the result under installation as a block key. 9. The device according to claim 1, characterized in that the cryptographic tool is configured to generate a unique device key either from a key of a large integrated circuit stored in a large integrated circuit contained in a cryptographic tool or from a device key stored in an information recording device, either from a media key stored in a storage medium, or from a drive key stored in a drive block for a storage medium, or based on a combination of these keys and generating a block key A block of data encryption device unique key and the block seed. 10. The device according to claim 1, characterized in that the cryptographic tool is configured to encrypt block data using a block key in accordance with the DES algorithm (data encryption standard). 11. The device according to claim 1, characterized in that it further comprises interface means adapted to receive information to be recorded on the information medium and to identify copy control information attached to each of the packets included in the transport stream for determination based copy control information whether or not recording is allowed on the storage medium. 12. The device according to claim 1, characterized in that it further comprises interface means adapted to receive information to be recorded on the storage medium and to identify the two-bit encryption mode indicator (EMI) as copy control information for determination based on EMI, whether or not recording is allowed on the storage medium. 13. An apparatus for reproducing information from an information medium, comprising: reproducing means configured to read information from an information medium; cryptographic means configured to decrypt the encrypted data read by the reproducing means by generating a block key for decrypting the encrypted block data having an entry time stamp attached to each of the plurality of transport packets from the initial number of the block, which is additional information unique to the data block, including the timestamp of the entry, and decryption of each data block thus generated by the block key, and the processing means t ansportnogo stream to output control data on the basis of input time tags attached to each of the plurality of transport packets included in the block data deciphered by using the cryptographic means. 14. The device according to item 13, wherein the cryptographic tool is configured to generate a block key for decrypting block data from the initial number of the block, which is additional information unique to the block data, and includes an entry time stamp attached to the first packet from multiple transport packets included in the block data. 15. The device according to item 13, wherein the cryptographic tool is configured to generate a unique title key from the master key stored in the information reproducing device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, and generating a block key from a unique title key and a block starting number. 16. The device according to item 13, wherein the initial number of the block includes copy control information in addition to the entry time stamp. 17. The device according to item 13, wherein the cryptographic tool is configured to decrypt using the block key only the data included in the block data, and to exclude from the decryption of additional data in the initial zone containing the initial number of the data block. 18. The device according to item 13, wherein the cryptographic tool is configured to generate a unique title key from the main key stored in the information reproducing device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, using the unique title key generated in this way as a key for the encryption function, substituting the initial number of blocks in the encryption function and the output of the substitution result as a block key. 19. The device according to item 13, wherein the cryptographic tool is configured to generate a unique title key from the master key stored in the information reproducing device, the disk identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to data to be recorded on the storage medium, substituting the unique title key generated in this way and the starting number of the block into a one-way function and issuing the result ltata substitution as a block key. 20. The device according to item 13, wherein the cryptographic tool is configured to generate a unique device key either from a key of a large integrated circuit stored in a large integrated circuit contained in a cryptographic tool or from a key of a device stored in an information recording device, either from a media key stored in a storage medium, or from a drive key stored in a drive block for a storage medium, or based on a combination of these keys and generating a block key to decrypt the block data from the unique key of the device key generated in this way and the initial number of the block. 21. The device according to item 13, wherein the cryptographic tool is configured to decrypt block data using a block key in accordance with the DES algorithm (data encryption standard). 22. The device according to p. 13, characterized in that it further comprises interface means configured to receive information to be recorded on the storage medium and identify copy control information attached to each of the packets included in the transport stream for determination based copy control information whether or not playback from the storage medium is allowed. 23. The device according to item 13, characterized in that it further comprises an interface means configured to receive information to be reproduced from the storage medium, and the identification of a two-bit encryption mode indicator (EMI) as copy control information for determination based on EMI, is allowed or not playback from the storage medium. 24. A method of recording information on a storage medium comprising the step of attaching an entry time stamp to each of the individual transport packets included in the transport stream, the step of generating a block key for encrypting block data including more than one transport packet, each of which has an attached entry time stamp , from the initial number of the block, which is additional information unique to the data of the block, and includes the timestamp of the entry, and the stage of encryption of each data block using the gene the block key thus generated; while encrypted data is recorded on the storage medium. 25. The method according to paragraph 24, wherein generating a block key for encrypting the block data from the initial block number, which is additional information unique to the block data, and includes an entry time stamp attached to the first packet from a plurality of transport packets included into block data. 26. The method according to p. 24, characterized in that they generate a unique title key from the main key stored in the information recording device, the disk identifier, which is the identifier of the information carrier unique to the information carrier, and a title key unique to the data to be recorded on the storage medium, and generate a block key from a unique title key and the starting number of the block. 27. The method according to p. 24, characterized in that it further comprises the step of generating a disk identifier, which is the identifier of the information medium unique to the information medium, the stage of generating a title key unique to the data to be recorded on the information medium, and the stage of storing them on the medium information. 28. The method according to paragraph 24, wherein the block key encrypts only the data included in the block data and excludes additional data from the encryption in the initial zone containing the initial number of the data block. 29. The method according to p. 24, characterized in that they generate a unique title key from the master key stored in the information recording device, the disk identifier, which is the identifier of the information medium unique to the information medium, and a title key unique to the data to be recorded on information carrier, use the unique title key generated in this way as a key for the encryption function, substitute the initial number of the block into the encryption function and issue the result of the substitution as a block ary key. 30. The method according to p. 24, characterized in that they generate a unique title key from the master key stored in the information recording device, the disk identifier, which is the identifier of the information carrier unique to the information carrier, and a title key unique to the data to be recorded on information carrier, substitute the unique title key generated in this way and the starting number of the block into a one-way function and output the result of the substitution as a block key. 31. The method according to paragraph 24, wherein generating a unique device key either from a key of a large integrated circuit stored in a large integrated circuit contained in a cryptographic tool, or from a key of a device stored in an information recording device, or from a media key, stored in the storage medium, and a drive key stored in the drive block for the storage medium, or based on a combination of these keys and generate a block key for encrypting the block data from a unique device key, is generated This way, and the initial number of the block. 32. The method according to paragraph 24, wherein the block data is encrypted using a block key in accordance with the DES algorithm (data encryption standard). 33. The method according to p. 24, characterized in that it further comprises the step of identifying copy control information attached to each of the packets included in the transport stream to determine, based on the copy control information, whether or not recording is allowed on the storage medium. 34. The method according to p. 24, characterized in that it further comprises the step of identifying a two-bit encryption mode indicator (EMI) as copy control information for determining, based on the EMI, whether or not recording is allowed on the storage medium. 35. A method of reproducing information from an information medium, comprising the step of reading information from the information medium, the step of decrypting encrypted data read by reproduction by generating a block key for decrypting encrypted block data having an entry time stamp attached to each of a plurality of transport packets from the initial number of the block, which is additional information unique to the data of the block, and includes a timestamp of the entry, the stage of decryption of each block data generated in this way with a block key, and the stage of processing the transport stream using processing means to control the output of data based on the timestamp of the input attached to each of the many transport packets included in the data block decrypted at the stage of decryption. 36. The method according to claim 35, characterized in that a block key is generated for decrypting the block data from the initial number of the block, which is additional information unique to the block data and includes an entry time stamp attached to the initial packet from a plurality of transport packets included into block data. 37. The method according to claim 35, characterized in that a unique title key is generated from the master key stored in the information reproducing apparatus, the disc identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to the data to be recorded on information carrier, and generate a block key from a unique title key and the starting number of the block. 38. The method according to claim 35, characterized in that only the data included in the block data is decrypted using the block key, and additional data located in the initial zone containing the initial number of the data block is excluded from decryption. 39. The method according to claim 35, characterized in that a unique title key is generated from the master key stored in the information reproducing apparatus, the disc identifier, which is the identifier of the information medium unique to the information medium, and the title key unique to the data to be recorded on information carrier, use the unique title key generated in this way as a key for the encryption function, substitute the initial number of the block into the encryption function and issue the result of the substitution in as a block key. 40. The method according to claim 35, characterized in that a unique title key is generated from the master key stored in the information reproducing apparatus, the disc identifier, which is the identifier of the information carrier unique to the information carrier, and the title key unique to the data to be recorded on the information carrier, substitute the unique title key generated in this way and the starting number of the block into a one-way function and output the result of the substitution as a block key. 41. The method according to claim 35, characterized in that a unique device key is generated either from a key of a large integrated circuit stored in a large integrated circuit contained in a cryptographic tool or from a key of a device stored in an information reproducing device or from a media key, stored on a storage medium, or from a drive key stored in a drive block for a storage medium, or based on a combination of these keys, a block key is generated to decrypt the block data from a unique device key Twa generated thereby, and the seed block. 42. The method according to clause 35, wherein decrypt the block data using a block key in accordance with the DES algorithm. 43. The method according to claim 35, further comprising a step of identifying the copy control information attached to each of the packets included in the transport stream to determine, based on the copy control information, whether or not playback from the storage medium is allowed. 44. The method according to claim 35, further comprising the step of identifying a two-bit encryption mode indicator (EMI) as copy control information for determining, based on the EMI, whether or not playback from the information medium is allowed. 45. A storage medium containing block data recorded thereon, including more than one packet included in the transport stream and having an entry time stamp attached to each of the packets, wherein the block data includes an unencrypted data part containing a random block number including a time stamp the input from which the block key is generated for encrypting the block data, and the encrypted part of the data encrypted with the block key. 46. A storage medium containing a computer program under which the computer performs the operation of attaching an entry time stamp to each of the individual transport packets included in the transport stream, an operation of generating a block key for encrypting block data including more than one transport packet, each of which has an attached timestamp of the entry, from the initial number of the block, which is additional information unique to the data of the block and including the timestamp of the entry, and the operation Figuring all block data with the block key generated in this way. 47. A storage medium containing a computer program under which the computer performs a block key generation operation for decrypting encrypted block data having an entry time stamp attached to each of the plurality of transport packets from the initial number of the block, which is additional information unique to the block data , and including the timestamp of the entry, the operation of decrypting all the data of the block using the block key thus generated and the operation of processing the transport sweat ka for controlling the output data based on input time tags attached to each of the plurality of transport packets included in the decrypted data block.

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