JP4601153B2 - Data terminal device and control method of data terminal device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a data terminal device used in a data distribution system that enables copyright protection for copied information.
[0002]
[Prior art]
In recent years, with the advancement of information communication networks such as the Internet, it has become possible for each user to easily access network information using a personal terminal using a playback terminal or the like.
[0003]
In such an information communication network, information is transmitted by digital signals. Therefore, for example, even when each individual user copies music or video data transmitted in the information communication network as described above, the data is copied with almost no deterioration in sound quality and image quality due to such copying. It is possible.
[0004]
Therefore, when a creative work such as music data or image data is transmitted on such an information and communication network, the copyright will be significantly reduced unless appropriate copyright protection measures are taken. The right of the right holder may be infringed.
[0005]
On the other hand, if it is impossible to distribute copyrighted material data over the rapidly expanding digital information communication network with the highest priority on copyright protection, basically, when copying copyrighted material data, a certain amount of Even for copyright holders who can collect copyright fees, it is disadvantageous.
[0006]
Here, instead of distribution through the digital information communication network as described above, taking a recording medium on which digital data is recorded as an example, a CD (compact disc) on which music data that is usually sold is recorded. In principle, music data can be copied from a CD to a magneto-optical disk (MD or the like) as long as the copied music is stopped for personal use. However, an individual user who performs digital recording or the like pays a certain amount of the price of the digital recording device itself or a medium such as an MD indirectly as a copyright fee to the copyright holder.
[0007]
In addition, when music data, which is a digital signal, is copied from a CD to an MD, it is copied as music data from a recordable MD to another MD in view of the fact that these pieces of information are digital data with little copy deterioration. Can not be configured in the equipment for copyright protection.
[0008]
For these reasons, the distribution of music data and image data to the public through a digital information communication network is an act that is restricted by the copyright holder's public transmission rights. Sufficient measures need to be taken.
[0009]
In this case, for content data such as music data and image data that are copyrighted works transmitted to the public through the information communication network, the content data once received can be further copied or used even if it can be copied. It is necessary to prevent this.
[0010]
Therefore, a data distribution system in which a distribution server that holds encrypted content data obtained by encrypting content data distributes encrypted content data to a memory card attached to a terminal device such as a playback terminal via the terminal device Proposed. In this data distribution system, a public encryption key of a memory card that has been authenticated in advance by a certificate authority and its certificate are transmitted to the distribution server when a distribution request for encrypted content data is made, and the certificate that the distribution server is authenticated is transmitted. After confirming reception, the encrypted content data and a license key for decrypting the encrypted content data are transmitted to the memory card. When distributing encrypted content data and a license key, the distribution server and the memory card generate a different session key for each distribution, encrypt the public encryption key with the generated session key, Exchange keys between memory cards.
[0011]
Finally, the distribution server transmits the license encrypted with the public encryption key of each memory card and further encrypted with the session key and the encrypted content data to the memory card. Then, the memory card records the received license and encrypted content data on the memory card.
[0012]
Then, when reproducing the encrypted content data recorded on the memory card, the memory card is attached to the mobile phone. In addition to the normal telephone function, the mobile phone also has a dedicated circuit for decrypting encrypted content data from the memory card, reproducing it, and outputting it to the outside.
[0013]
As described above, the user of the mobile phone can receive the encrypted content data from the distribution server using the mobile phone and reproduce the encrypted content data.
[0014]
On the other hand, encrypted content data is also distributed to personal computers using the Internet. Although it is possible to distribute the encrypted content data and the license to the personal computer in the same manner, the distribution of the encrypted content data and the license is received by the software installed in the personal computer, and the license is protected. The received encrypted content data and the license are not transferred to another personal computer from the viewpoint of copyright protection.
[0015]
That is, another personal computer is used as it is by using encryption processing associated with values such as an identification number individually assigned to the CPU of the personal computer that records the license distributed to the personal computer and a BIOS identification number as a start program. The management structure is adopted in which the license cannot be taken out even if copied to, and the encrypted content cannot be decrypted and reproduced. Then, if a service is provided under which this license can be transferred to another personal computer, the encrypted content data and license are managed and recorded, although the license cannot be specified on the recording device. All the data that has been backed up, and the encrypted content data and licenses that were backed up are managed and recorded after the encrypted content data and licenses have been transferred to another personal computer by the provided service If the data is returned to the personal computer, the state before the transfer can be reproduced, which is the same as copying the encrypted content data and the license. There is clearly a security hole in the movement of licenses in such management. Therefore, the encrypted content data and license distributed to the personal computer by software cannot be transferred to another personal computer.
[0016]
[Problems to be solved by the invention]
However, if the encrypted content data and license distributed to the personal computer cannot be taken out from the personal computer at all, if the CPU changes due to damage to the personal computer or version upgrade, the encrypted data already received is received. There is a problem that the content data and license cannot be used.
[0017]
Therefore, the present invention has been made to solve such a problem, and an object thereof is to provide a data terminal device capable of moving encrypted content data and license distributed by software to another data terminal device. It is to be.
[0018]
[Means for Solving the Problems and Effects of the Invention]
The data terminal device according to the present invention acquires encrypted content data obtained by encrypting content data and a license for decrypting the encrypted content data to obtain the original plaintext, and the encrypted content data and license are transferred to another data terminal. A data terminal device that outputs to the device, a module unit that acquires encrypted content data and a license by software, an encrypted content data, a license management file, and a storage unit that stores an encrypted confidential file; A device unit that decrypts the encrypted confidential file and stores a binding license including a binding key for encrypting the decrypted confidential file in a dedicated area, and the confidential file stores confidential information including the license as a component. Including license management file It corresponds to the encrypted content file, and includes a management number of the confidential information contained in the confidential file.
[0019]
In the data terminal device according to the present invention, the module unit obtains the encrypted content data and license by software, decrypts the encrypted confidential file with the binding key extracted from the device unit, and converts the acquired license into the decrypted confidential file. Write and encrypt the confidential file with the binding key to generate an encrypted confidential file. That is, the module unit manages the license obtained by opening and closing the encrypted confidential file via the binding key held by the hardware in the device unit.
[0020]
Therefore, according to the present invention, since the license for decrypting and playing back the encrypted content data acquired by software is managed by the binding key held in the hardware, the acquired encrypted content data and license Can be moved to another data terminal device.
[0021]
Preferably, when the encrypted confidential file is initialized, the module unit of the data terminal device generates a binding license including the binding key, generates a confidential file with empty confidential information, and generates the generated confidential file. The encrypted secret file is generated by encryption with the binding key, and the generated binding license is given to the device unit.
[0022]
When initializing an encrypted confidential file, the module unit generates a binding license including a binding key and an empty confidential file, encrypts the confidential file with the binding key, generates an encrypted confidential file, and generates a binding license. Is held in the device section.
[0023]
Therefore, according to the present invention, it is possible to create a confidential file for storing the license of the encrypted content data acquired by software in software and to manage a binding license for managing the created confidential file in hardware.
[0024]
Preferably, when acquiring the license, the module unit of the data terminal device decrypts the encrypted confidential file read from the storage unit with the binding key acquired from the device unit, and uses the acquired license as the confidential information in the decrypted confidential file. Updates the confidential file by writing, encrypts the updated confidential file with the binding key, updates the encrypted encrypted confidential file in the storage unit, and manages the confidential information with the written license as a component Create a license management file containing the number and write it to the storage.
[0025]
The license acquired by opening and closing the encrypted confidential file with the binding key acquired from the device part is written in the confidential file. Then, a license management file including the management number of confidential information having the written license as a component is created.
[0026]
Therefore, according to the present invention, the license of encrypted content data acquired in software can be managed by the management number.
[0027]
Preferably, at the time of transmitting the license, the module unit of the data terminal device acquires the license by decrypting the encrypted confidential file read from the storage unit with the binding key acquired from the device unit, and outputs the acquired license to the outside To do.
[0028]
The module unit decrypts the encrypted confidential file with the binding key acquired from the device unit, acquires the license, and outputs the acquired license to the outside.
[0029]
Therefore, according to the present invention, the license of encrypted content data acquired in software can be transferred to another device in the same manner as the license of encrypted content data acquired in hardware.
[0030]
Preferably, the module unit of the data terminal device outputs the encrypted content data and the license corresponding to the license and recorded in the storage unit to the outside when the license is output.
[0031]
When the license is output to the outside, the encrypted content data corresponding to the license extracted from the confidential file is read from the storage unit, and the encrypted content data and the license are output to the outside.
[0032]
Therefore, according to the present invention, the encrypted content data and license can be read out in software, and the encrypted content data and license can be transferred to another device.
[0033]
Preferably, the device unit of the data terminal apparatus receives a dedicated registration number for designating a dedicated area from the module unit, and stores the binding license in the dedicated area based on the received dedicated registration number.
[0034]
The device unit stores a binding license for opening and closing the encrypted confidential file via the dedicated registration number in the dedicated area.
[0035]
Therefore, according to the present invention, the binding license and the license of the encrypted content data can be associated with each other by the dedicated registration number.
[0036]
Preferably, when the license is output, the module unit of the data terminal device acquires the binding key by transmitting a dedicated registration number to the device unit.
[0037]
The module unit obtains a binding key for opening a confidential file storing a license to be read from the storage unit via the dedicated registration number.
[0038]
Therefore, according to the present invention, the binding key can be accurately obtained from the dedicated registration number.
[0039]
Preferably, when outputting the license, the module unit of the data terminal device transmits authentication data for the device unit to the device unit, and acquires the binding key when the authentication data is authenticated in the device unit.
[0040]
Only the authenticated module part is given a binding key.
Therefore, according to the present invention, an illegal binding key can be prevented from being leaked.
[0041]
Preferably, at the time of outputting the license, the device unit of the data terminal device encrypts and outputs the binding key.
[0042]
The device unit encrypts and outputs a binding key for managing the license.
[0043]
Therefore, according to the present invention, when the license is moved to another device, it is difficult to illegally acquire the binding key for managing the license at the destination.
[0044]
Preferably, when outputting the license, the module unit of the data terminal device acquires the confidential file by decrypting the encrypted confidential file with the acquired binding key, and the confidential information included in the license management file read from the storage unit The license to be output to the outside is obtained by reading out the confidential information matching the management number of the file from the acquired confidential file.
[0045]
The module unit obtains the binding key from the device unit, decrypts the encrypted confidential file, acquires the confidential information that matches the management number from the confidential information contained in the decrypted confidential file, and outputs it to the outside To get.
[0046]
Therefore, according to the present invention, the license can be accurately acquired via the management number.
[0047]
Preferably, when the license is transmitted to another data terminal device, the module unit of the data terminal device further receives the public encryption key held in the device unit, so that the device unit can write the binding license. Confirm.
[0048]
When transmitting the license to another apparatus, the module unit confirms whether the device unit is a device unit capable of writing the binding license by receiving a public encryption key from the device unit.
[0049]
Therefore, according to the present invention, when the license of the encrypted content data is moved, it is possible to recognize that the license has been moved by rewriting the binding license stored in the device unit.
[0050]
Preferably, when the encrypted content data is transferred to another data terminal device, the module unit of the data terminal device, when the license cannot be duplicated, reads the confidential information including the license transmitted to the other data terminal device as a component. Delete, delete the management number of the deleted confidential information, update the license management file, generate another binding key, encrypt the confidential file with the generated another banding key, and encrypt the confidential file Update.
[0051]
When copying of the moved license is prohibited, the module unit deletes the moved license and generates another binding key to update the encrypted confidential file.
[0052]
Therefore, according to the present invention, it is possible to prevent the license from being illegally copied.
[0053]
Preferably, when moving the encrypted content data to another data terminal device, the device unit of the data terminal device receives another binding license including another binding key from the module unit, and receives the received another one of the received licenses. Store the binding license by overwriting the dedicated area.
[0054]
When another binding key is generated, the device unit rewrites the binding license.
[0055]
Therefore, according to the present invention, the license for reproducing the encrypted content data can be managed with the latest binding license.
[0056]
Preferably, when the license is transmitted to another data terminal device, the module unit of the data terminal device transmits the license to the other data terminal device after authenticating the authentication data received from the other data terminal device.
[0057]
The module unit transmits the license for the encrypted content data after confirming that the data terminal device to which the license for the encrypted content data is to be transferred is a legitimate terminal device.
[0058]
Therefore, according to the present invention, the license of the encrypted content data can be transferred between legitimate data terminal devices, and the encrypted content data can be sufficiently protected.
[0059]
Preferably, the module unit of the data terminal device outputs the license after encrypting it.
[0060]
The module unit encrypts the license and moves to another data terminal device.
[0061]
Therefore, according to the present invention, it is difficult to illegally acquire the license when the license is moved.
[0062]
The data terminal device according to the present invention obtains a license for obtaining the original plaintext by decrypting the encrypted content data and the encrypted content data obtained by encrypting the content data, and transferring the encrypted content data and the license to another A data terminal device for outputting to a data terminal device, a module unit for acquiring encrypted content data and a license by software, an encrypted content data, a license management file, and an encrypted confidential data subjected to original encryption A storage unit for storing files and a device unit for storing a binding license including a binding key in a dedicated area. A confidential file obtained by decrypting an encrypted confidential file has the same binding license as the binding license stored in the device unit. Including License management file corresponds to the encrypted content data, and includes the encrypted confidential information which has been subjected to own encryption confidential information as components license.
[0063]
In the data terminal device according to the present invention, the module unit obtains encrypted content data and a license by software, performs original encryption on the obtained license, generates encrypted confidential information, and generates the generated encryption Create a license management file including the confidential information and write it to the storage unit. The binding license for managing the license is stored in a confidential file.
[0064]
Therefore, according to the present invention, since the binding key for managing the license is held by the hardware, the license for decrypting and playing back the encrypted content data acquired by the software is another data terminal device. Can move to.
[0065]
Preferably, when initializing the encrypted confidential file, the module unit of the data terminal device generates a binding license including the binding key, generates a confidential file storing the generated binding license, and generates the generated confidential file. An encrypted secret file is generated by applying original encryption to the device, and the generated binding license is given to the device unit.
[0066]
When the encrypted confidential file is initialized, the module generates a binding license including the binding key and an empty confidential file, writes the generated binding license in the confidential file, and performs its own encryption to encrypt the confidential information. A file is generated and the binding license is held in a dedicated area of the device unit.
[0067]
Therefore, according to the present invention, since the binding key for managing the license is held by the hardware, the license for decrypting and playing back the encrypted content data acquired by the software is another data terminal device. Can move to.
[0068]
Preferably, at the time of acquiring the license, the module unit of the data terminal device performs encryption unique to the license to generate encrypted confidential information, generates a license management file including the encrypted confidential information, and stores it in the storage unit. Write.
[0069]
The module unit performs original encryption on the acquired license and manages it in the storage unit.
[0070]
Therefore, according to the present invention, the license can be managed by a unique encryption method.
[0071]
Preferably, when the license is transmitted, the module unit of the data terminal device reads the encrypted confidential information read from the storage unit when the binding key acquired from the device unit matches the binding key acquired by decrypting the encrypted confidential file. The license is obtained by decryption, and the obtained license and the encrypted content data read from the storage unit are transmitted to another data terminal device.
[0072]
The module unit acquires a license only when the binding key stored in the device unit matches the binding key stored in the storage unit.
[0073]
Therefore, only the module unit having the same binding key as the hardware-managed binding key can acquire the license.
[0074]
Preferably, the unique encryption method is an encryption method associated with information unique to the data terminal device that can be acquired from the data terminal device.
[0075]
The module unit encrypts the license by an encryption method based on information unique to the data terminal device, for example, the version number of the CPU.
[0076]
Therefore, according to the present invention, even if an encrypted license is illegally leaked to another device, the license is not illegally acquired.
[0077]
Preferably, the device unit of the data terminal device receives a dedicated registration number for designating a dedicated area from the module unit, and stores the binding license in the dedicated area by the received dedicated registration number, and the module unit includes the dedicated registration number. To generate an encrypted confidential file and a license management file.
[0078]
The device unit manages the binding license by hardware using the dedicated registration number generated by the module unit, and the module unit independently manages the generated dedicated registration number and the acquired license by software.
[0079]
Therefore, according to the present invention, the module unit acquires the binding key held in the device unit via the dedicated registration number, and the binding key read from the encrypted confidential file matches the binding key acquired from the device unit. Can be accurately determined.
[0080]
Preferably, when the license is transmitted, the module unit of the data terminal device acquires the binding key by transmitting the dedicated registration number to the device unit.
[0081]
The module unit transmits the dedicated registration number to the device unit, and the device unit extracts and outputs the binding key from the dedicated area specified by the received dedicated registration number.
[0082]
Therefore, according to the present invention, the binding key can be accurately obtained from the dedicated registration number.
[0083]
Preferably, when the license is transmitted to another data terminal device, the module unit of the data terminal device transmits authentication data for the device unit to the device unit, and obtains a binding key when the authentication data is authenticated in the device unit. To do.
[0084]
The module unit obtains the binding key only when the validity of the module unit with respect to the device unit is confirmed.
[0085]
Therefore, according to the present invention, unauthorized acquisition of the binding key can be prevented, and as a result, the license can be prevented from being illegally transferred to another terminal device.
[0086]
Preferably, when the license is transmitted to another data terminal device, the module unit of the data terminal device transmits the license to the other data terminal device after authenticating the authentication data received from the other data terminal device.
[0087]
When it is confirmed that the data terminal device to which the encrypted content data and license are to be transferred is authentic, the module unit transmits the encrypted content data and license to another data terminal device.
[0088]
Therefore, according to the present invention, encrypted content data and licenses can be transferred only between legitimate data terminal devices.
[0089]
Preferably, the module unit of the data terminal device acquires encrypted content data and a license from the distribution server via the Internet.
[0090]
Therefore, according to the present invention, it is possible to acquire various types of content data and move the acquired content data to another terminal device.
[0091]
Preferably, the data terminal device further includes a medium driving unit that reads plaintext content data from the recording medium, and the module unit generates a license based on duplication permission / inhibition information included in the content data read by the medium driving unit. Then, the encrypted content data and the license are obtained by generating the encrypted content data by encrypting the content data with the license key included in the generated license.
[0092]
The data terminal device acquires encrypted content data and a license by ripping.
[0093]
Therefore, according to the present invention, content data distributed by means other than the communication means can also be acquired and transferred to another data terminal device.
[0094]
Preferably, the device unit of the data terminal device further receives the encrypted content data and the license from the distribution server, holds the received license, and the storage unit stores the encrypted content data received by the device unit. To do.
[0095]
The device unit holds the binding license, receives the encrypted content data and the license from the distribution server, and holds the received license together with the binding license.
[0096]
Therefore, according to the present invention, a license acquired by hardware and a license acquired by software can be managed at almost the same security level.
[0097]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.
[0098]
[Embodiment 1]
FIG. 1 shows an overall configuration of a data distribution system in which a data terminal device (personal computer) according to the present invention acquires encrypted content data and moves the acquired encrypted content data to another data terminal device (personal computer). It is the schematic for demonstrating conceptually.
[0099]
In the following description, the configuration of a data distribution system that distributes digital music data to users of personal computers via the Internet will be described as an example. As will be apparent from the following description, the present invention is applied to such a case. Without limitation, the present invention can also be applied to the case of distributing content data as other copyrighted works, for example, image data, moving image data, and the like.
[0100]
Referring to FIG. 1, personal computer 50 transmits a distribution request (distribution request) from a user of each personal computer to distribution server 10 via modem 40 and Internet network 30. The distribution server 10 that manages copyrighted music data determines whether or not the personal computer 50 owned by the user of the personal computer that has accessed for data distribution has valid authentication data. The personal computer performs an authentication process as to whether or not content protection with a sufficient security level is performed, and music data (hereinafter also referred to as content data) is transmitted to the personal computer performing legitimate content protection by a predetermined encryption method. ) Is encrypted, and the license as information necessary for reproducing such encrypted content data and encrypted content data is distributed to the personal computer 50.
[0101]
In this case, the personal computer 50 can receive and manage the encrypted content data and license from the distribution server 10 via the modem 40 and the Internet network 30 with different security levels. That is, the personal computer 50 includes a license management device that realizes content protection in hardware and a license management module that realizes content protection in software. The license management device receives encrypted content data and a license from the distribution server 10 via the Internet network 30 or the like with the help of application software. This license management device establishes an encrypted communication path for receiving a license for reproducing encrypted content data directly with a distribution server, and holds the received license in hardware. Security level is high. Similarly, the license management module establishes an encrypted communication path according to a predetermined procedure with the distribution server, receives the license, encrypts it, protects it, and then licenses it to the hard disk (referred to as HDD). Record. The encrypted content data and license are received and managed at a lower security level than the license management device. In either case, the encrypted content data is recorded on the HDD as it is. The license management device and the license management module will be described in detail later.
[0102]
Hereinafter, in order to distinguish between the security level and the license, the security level that keeps confidentiality by the hardware such as the memory card 110 or the license management device is referred to as level 2, and the license transmitted from the distribution server requesting the security of level 2 Is referred to as a Level 2 license. Similarly, a security level that maintains confidentiality by software such as a license management module is referred to as level 1, and a license that requests a security level of level 1 and is transmitted from a distribution server is referred to as a level 1 license.
[0103]
Further, in FIG. 1, the personal computer 50 encrypts music data acquired from a music CD (Compact Disk) 60 in which music data is recorded using the license management module, and is limited to local use only for personal use. Content data and a license for reproducing the encrypted content data can be generated. This process is called ripping and corresponds to an act of acquiring encrypted content data and a license from a music CD. Since the license for local use by ripping has a security level that is never high due to its nature, it is assumed that it is treated as a level 1 license no matter what means is used for ripping. Details of ripping will be described later.
[0104]
Furthermore, the personal computer 50 is connected to the playback terminal 100 via a USB (Universal Serial Bus) cable 70 and transmits the encrypted content data and license received from the distribution server 10 to the memory card 110 attached to the playback terminal 100. It is possible.
[0105]
Further, the personal computer 50 transmits the received encrypted content data and license to the personal computer 80 via the communication cable 90.
[0106]
Therefore, in the data distribution system shown in FIG. 1, the personal computer 50 receives the encrypted content data and the license from the distribution server 10 via the modem 40 and the Internet network 30, and also receives the encrypted content data from the music CD. Get a license. The memory card 110 attached to the playback terminal 100 receives the encrypted content data and license acquired by the personal computer 50 from the distribution server 10 or the music CD 60. The user of the playback terminal 100 can obtain the encrypted content data and license from the music CD via the personal computer 50.
[0107]
In FIG. 1, for example, a removable memory card 110 is attached to a playback terminal 100 of a mobile phone user. The memory card 110 receives the encrypted content data received by the playback terminal 100, decrypts the encryption performed in the distribution, and gives it to a music playback unit (not shown) in the playback terminal 100.
[0108]
Further, for example, a mobile phone user can “reproduce” such content data via the headphones 130 connected to the reproduction terminal 100 and listen to the content data.
[0109]
In FIG. 1, the personal computer 50 uses the license management module, and only the encrypted content data having the level 1 license that is directly managed by the license management module is used as a music playback program that works closely with the license management module. It is possible to provide a function of reproducing using Reproduction of encrypted content data having a level 2 license is possible if the personal computer is provided with a content reproduction circuit having confidentiality by hardware having the same configuration as the reproduction terminal. A detailed description of playback on a personal computer will be omitted to simplify the description in the present application.
[0110]
With such a configuration, if the personal computer is not a personal computer having a proper license management device or license management module having a content protection function with a sufficient security level, the distribution server 10 receives the distribution of the content data and receives the personal data. It becomes difficult to transmit the encrypted content data to the computer 80 or the playback terminal 100.
[0111]
Moreover, in the distribution server 10, for example, by counting the frequency each time content data for one song is distributed, the copyright fee generated each time the user of the personal computer receives (downloads) the content data, If it is collected together with the usage fee for the Internet network, it becomes easy for the copyright holder to secure the copyright fee.
[0112]
In FIG. 1, the playback terminal 100 is assumed to be a playback terminal that does not have a function of directly communicating with the distribution server 10.
[0113]
In the configuration as shown in FIG. 1, in order to be able to reproduce the content data encrypted and distributed on the user side of the personal computer, the first thing required on the system is an encryption key for communication. The second method is to encrypt the content data to be distributed, and the third is to prevent unauthorized copying of the distributed content data. The content data protection is realized.
[0114]
In the embodiment of the present invention, particularly at the occurrence of each session of distribution, movement, check-out, check-in, and playback, the authentication and check functions for the destination of these content data are enriched, and non-authentication or Content data copyright protection is achieved by preventing output of content data to a recording device and a data reproduction terminal whose decryption key has been broken (a data reproduction terminal capable of reproducing content is also referred to as a reproduction terminal or a personal computer). The structure to strengthen is demonstrated.
[0115]
In the following description, processing for transmitting content data from the distribution server 10 to each personal computer or the like is referred to as “distribution”.
[0116]
FIG. 2 is a diagram for explaining characteristics of data, information, etc. for communication used in the data distribution system shown in FIG.
[0117]
First, data distributed from the distribution server 10 will be described. Dc is content data such as music data. The content data Dc is encrypted so that it can be decrypted with the license key Kc. Encrypted content data {Dc} Kc that has been decrypted by the license key Kc is distributed from the distribution server 10 to the user of the personal computer in this format.
[0118]
In the following, the notation {Y} X indicates that the data Y has been encrypted with the decryption key X.
[0119]
Further, the distribution server 10 distributes additional information Dc-inf as plain text information such as copyrights related to the content data or server access, along with the encrypted content data. In addition, a transaction ID, which is a management code for specifying the distribution of the license key Kc and the license key from the distribution server 10, is exchanged between the distribution server 10 and the personal computer 50 as a license. The transaction ID is also used to specify a license that is not distributed, that is, a license for local use for personal use. In order to discriminate between delivery and local use, the transaction ID beginning with “0” is the local use transaction ID, and the transaction ID beginning with other than “0” is the delivery transaction ID. And Furthermore, the license is generated based on a license purchase condition AC including information such as a content ID that is a code for identifying the content data Dc, the number of licenses determined by designation from the user side, and function limitations. There are access control information ACm, which is information relating to restrictions on access to the license in the recording device (memory card or license management device), reproduction control information ACp, which is control information in the data reproduction terminal, and the like. Specifically, the access restriction information ACm is control information for a memory card, a license management module, and a license or license key from the license management module that is suitable for output to the outside. Number of keys to be output), restriction information on transfer / copying of licenses, and license security level. The reproduction control information ACp is information for restricting reproduction after the content reproduction circuit receives the license key for reproduction, and includes reproduction time limit, reproduction speed change restriction, reproduction range designation (partial license), and the like.
[0120]
In the embodiment of the present invention, for simplification, the access restriction information ACm is control information for restricting the number of reproductions. The number of reproductions <0: reproduction impossible, 1 to 254: reproduction possible number, 255: no restriction), Move and copy flag that restricts license transfer and copy <0: Move copy prohibited, 1: Transfer only allowed, 2: Move copy allowed), security level “1: Level 1, 2: Level 2” and play The control information ACp restricts only the reproduction time limit “UTCtime code”, which is control information defining the reproducible time limit. Therefore, hereinafter, the reproduction control information ACp is also referred to as a reproduction time limit ACp.
[0121]
Further, hereinafter, the transaction ID and the content ID are collectively referred to as a license ID, and the license key Kc, the license ID, the access restriction information ACm, and the reproduction time limit ACp are collectively referred to as a license.
[0122]
In the embodiment of the present invention, distribution and reproduction of content data can be prohibited for each class of recording device (memory card, license management device and license management module) and reproduction terminal for reproducing content data. In addition, the prohibited class list CRL (Class Revocation List) is operated. Hereinafter, the data in the prohibited class list may be represented by the symbol CRL as necessary.
[0123]
The prohibited class list related information includes prohibited terminal list data CRL that lists the classes of playback terminals, memory cards, license management modules, and license management devices that are prohibited from distributing, moving, checking out, and playing licenses. It is. All devices and programs that manage and store licenses related to content data protection and play back licenses are eligible for listing.
[0124]
The prohibited class list data CRL is managed in the distribution server 10 and is also recorded and held in a hard disk (HDD) or license management device in the personal computer 50 by a memory card or a license management module. Such a prohibited class list needs to be updated at any time to update the data, but the data change is basically performed when distributing licenses such as encrypted content data and / or license keys. The update date and time of the prohibited class list received from the personal computer (license management device or license management module) is determined. When it is determined that the updated class list has not been updated, the updated prohibited class list is distributed to the personal computer. The prohibited class list is also exchanged between the license management module, the license management device, and the playback terminal 100, and the data change is the same as described above. Further, regarding the change of the prohibited class list, differential data CRL reflecting only the changed point is generated from the distribution server 10 side and added to the prohibited class list CRL in the memory card, hard disk, and license management device accordingly. It is also possible to adopt a configuration. The update date / time CRLdate of the prohibited class list is recorded in the prohibited class list CRL recorded in the memory card, hard disk, and license management device, and version management is performed by confirming this on the distribution server 10 side. Execute. The difference data CRL update date / time CRLdate is also included.
[0125]
In this way, the prohibited class list CRL is held and operated not only in the distribution server but also in the memory card or personal computer, so that it is specific to the class, that is, the reproduction terminal and the memory card or personal computer (license management device or license management module). The license key is prohibited from being supplied to the playback terminal and the memory card or personal computer whose decryption key is broken. For this reason, it becomes impossible for the playback terminal to play back the content data, and the memory card, license management module, and license management device cannot receive a new license.
[0126]
As described above, the prohibited class list CRL in the memory card or the license management device or in the HDD managed by the license management module is configured to sequentially update data at the time of distribution. In addition, the management of the prohibited class list CRL in the memory card, the license management module, and the license management device is performed by a tamper resistant module (a hard disk controlled by the memory card, the license management device, and the license management module independently of the upper level). Record in the Tamper Resistant Module). In the memory card or license management device, similarly to the license, management of the prohibited class list CRL recorded by the high-level tamper resist module that guarantees confidentiality in hardware and recorded in the HDD managed by the license management module Is recorded in a personal computer HDD or the like after at least tampering prevention processing is performed by encryption processing. In other words, it is recorded by a low level tamper resistant module whose confidentiality is guaranteed by software. In any case, the prohibited class list data CRL cannot be falsified from a higher level by a file system, an application program, or the like. As a result, the copyright protection regarding the data can be further strengthened.
[0127]
FIG. 3 is a diagram for explaining the characteristics of data, information, etc. for authentication used in the data distribution system shown in FIG.
[0128]
The playback terminal, the memory card, the license management device, and the license management module are each provided with a unique public encryption key KPpy and KPmw, and the public encryption keys KPpy and KPmw are a secret decryption key Kpy and a memory card, license unique to the playback terminal. Each can be decrypted by a secret decryption key Kmw unique to the management device and the license management module. These public encryption key and secret decryption key have different values for each type of playback terminal, memory card, license management device, and license management module. These public encryption keys and secret decryption keys are collectively referred to as class keys, these public encryption keys are referred to as class public encryption keys, secret decryption keys are referred to as class secret decryption keys, and units sharing the class keys are referred to as classes. Classes differ depending on the manufacturer, product type, production lot, and the like.
[0129]
Also, Cpy is provided as a class certificate for the content playback device (playback terminal), and Cmw is provided as a class certificate for the memory card, license management device, and license management module.
[0130]
These class certificates have different information for each class of content playback device, memory card, license management device, and license management module. If the tamper resistant module is broken or the encryption by the class key is broken, that is, the class key for which the class secret decryption key has been obtained, it will be listed in the prohibited class list and will not be subject to license transmission. Become.
[0131]
The class public encryption key and class certificate unique to these content reproduction device, memory card, license management device, and license management module are in the form of authentication data {KPpy // Cpy} KPa or authentication data {KPmw // Cmw}. In the KPa format, it is recorded in the data playback device (playback terminal), memory card, license management device, and license management module at the time of shipment. As will be described in detail later, KPa is a public authentication key common to the entire distribution system.
[0132]
Furthermore, as a key for managing data processing in the memory card 110, the license management device, and the license management module, a public encryption set for each medium or management software of the memory card, the license management device, and the license management module There is a unique secret decryption key Kmcx that can decrypt the data encrypted with the key KPmcx and the public encryption key KPmcx. The public encryption key and secret decryption key that are child-specific for each memory card are collectively referred to as an individual key, the public encryption key KPmcx is referred to as an individual public encryption key, and the secret decryption key Kmcx is referred to as an individual secret decryption key.
[0133]
As an encryption key for maintaining confidentiality in data transfer between memory cards and between memory cards, data transfer between license management devices and license management devices, or data transfer between license management modules and license management modules The common keys Ks1 to Ks3 generated in the distribution server 10, the reproduction terminal 100, the memory card 110, the license management device, and the license management module are used every time content data is distributed and reproduced.
[0134]
Here, the common keys Ks1 to Ks3 are unique common keys generated for each “session” which is a unit of communication or a unit of access between a distribution server, a reproduction terminal, a memory card, a license management device, or a license management module. Hereinafter, these common keys Ks1 to Ks3 are also referred to as “session keys”.
[0135]
These session keys Ks1 to Ks3 are managed by the distribution server, playback terminal, memory card, license management device, and license management module by having a unique value for each session. Specifically, the session key Ks1 is generated for each distribution session by the distribution server. The session key Ks2 is generated for each distribution session and reproduction session by the memory card, the license management device, and the license management module, and the session key Ks3 is generated for each reproduction session at the reproduction terminal. In each session, these session keys are exchanged, the session keys generated by other devices are received, the encryption with this session key is performed, and the license key etc. is transmitted, so that the security strength in the session Can be improved.
[0136]
FIG. 4 shows a binding license necessary for encrypting and managing encrypted content data and a license acquired by software (license management module) in association with a license management device so that the license can be transferred to another personal computer. FIG. 6 shows checkout management information in a checkout session in which encrypted content data acquired by software and a license are lent to the memory card 110. FIG.
[0137]
The binding license is a level 1 license for reproducing encrypted content data, a binding key that is a common key for realizing a soft tamper resistant module by encrypting information related to license checkout, and a binding license. It consists of control information ACmb and ACpb, a transaction IDb that is a transaction ID for a binding license, a content IDb that is a dummy for a binding ID, and a binding ID that is a generic name of the transaction IDb and the content IDb. That is, since it is premised on recording as a license in the license management device, it has the same configuration as the license.
[0138]
The binding key Kb manages the license of the encrypted content data acquired by software, and is held by hardware. The license cannot be taken out without using the binding key Kb held by the hardware. The control information ACmb and ACpb correspond to ACm and ACp included in the license for reproducing the encrypted content data, and have fixed values. ACmb represents that there is no limit on the number of times the license can be played, mobile copying is prohibited, and security level 1. ACpb represents that the playing time limit is indefinite.
[0139]
The check-out management information includes a check-out possible number, a check-out destination individual ID, and a check-out transaction ID. The number of checkouts possible indicates the number of times that the encrypted content data can be lent, and every time the encrypted content data is checked out, the numerical value is decremented by 1 and every time the encrypted content data is checked in. The numerical value is incremented by one. The checkout destination individual ID is identification information for specifying a memory card for checking out encrypted content data, and corresponds to the individual public encryption key KPmcx held by the memory card. The transaction ID at the time of checkout is a transaction ID for local use used at the time of checkout.
[0140]
FIG. 5 is a schematic block diagram showing the configuration of the distribution server 10 shown in FIG.
The distribution server 10 follows the start of access to the content data for each user of the personal computer and the information database 304 for holding the distribution data such as the content data encrypted according to a predetermined method and the content ID. A charging database 302 for storing charging information, a CRL database 306 for managing the prohibited class list CRL, a menu database 307 for storing a menu of content data stored in the information database 304, and content data for each license distribution And a distribution record database 308 that records and maintains the distribution of transaction IDs that specify the distribution of license keys and the like, an information database 304, a charging database 302, a CRL database 306, a menu, and the like. Data processing unit 310 for receiving data from database 307 and distribution record database 308 via bus BS1 and performing predetermined processing, and between distribution carrier 20 and data processing unit 310 via a communication network And a communication device 350 for exchanging data.
[0141]
The data processing unit 310 is controlled by the distribution control unit 315 for controlling the operation of the data processing unit 310 and the distribution control unit 315 according to the data on the bus BS1, and generates a session key Ks1 during the distribution session. Session key generation unit 316 for authentication, authentication key holding for holding public authentication key KPa for decrypting authentication data {KPmw // Cmw} KPa sent from the license management device and the license management module Authentication data {KPmw // Cmw} KPa sent from the unit 313, the license management device, and the license management module is received via the communication device 350 and the bus BS1, and sent from the authentication key holding unit 313. A decryption processing unit 312 that performs decryption processing using the public authentication key KPa, and a set The session key Ks1 generated by the key generation unit 316 is encrypted using the class public encryption key KPmw obtained by the decryption processing unit 312 and output to the bus BS1, and the session key Ks1 A decryption processing unit 320 that receives the encrypted data transmitted from the bus BS1 and performs decryption processing.
[0142]
The data processing unit 310 further receives the license key Kc and the access restriction information ACm given from the distribution control unit 315, and the individual public encryption key KPmcx of the memory card, license management device, and license management module obtained by the decryption processing unit 320. An encryption processing unit 326 for encrypting using the encryption key, and an encryption processing unit 328 for further encrypting the output of the encryption processing unit 326 with the session key Ks2 given from the decryption processing unit 320 and outputting the result to the bus BS1. including.
[0143]
The authentication key held by the distribution server varies depending on the security level of the receiving side requested by the license to be distributed by the distribution server. In a distribution server that distributes a level 2 license that requires security level 2, an authentication key KPa2 that can perform authentication processing on authentication data transmitted by a device with a security level of 2 is held. Further, in a distribution server that distributes a level 1 license that requires a security level 1 for a license to be distributed, it can be distributed to both a device with a security level of level 2 and a device with a security level of level 1. Therefore, the authentication keys KPa2 and KPa1 corresponding to the level 2 and level 1 are held, and are used properly according to the level of the other party. Furthermore, even if the authentication key required by the transmitted authentication data is encrypted as the authentication data of the class certificate Cmw, it is described in the area maintained as plain text and the distribution control unit 315 of the distribution server 10 The decryption processing unit 312 can easily specify the authentication key before decryption. In order to distinguish the two authentication keys, the authentication key KPa2 corresponding to level 2 is referred to as level 2 authentication key KPa2, the authentication key KPa1 corresponding to level 1 is referred to as level 1 authentication key KPa1, and is generally referred to as authentication key KPa.
[0144]
The operation in the distribution session of the distribution server 10 will be described in detail later using a flowchart.
[0145]
FIG. 6 is a schematic block diagram for explaining the configuration of the personal computer 50 shown in FIG. The personal computer 50 includes a bus BS2 for exchanging data of each part of the personal computer 50, a controller (CPU) 510 for executing various programs while controlling the inside of the personal computer, a data bus BS2, and data A hard disk (HDD) 530 and a CD-ROM drive 540 that are connected to the bus BS2 and record and store programs and data, and a keyboard 560 for inputting instructions from the user And a display 570 for visually giving various kinds of information to the user.
[0146]
The personal computer 50 further connects a USB interface 550 and a USB cable 70 for controlling data exchange between the controller 510 and the terminal 580 when the encrypted content data and license are communicated to the playback terminal 100 or the like. A terminal 580 for performing communication, a serial interface 555 for controlling data exchange between the controller 510 and the terminal 585 when communicating with the distribution server 10 via the Internet network 30 and the modem 40, and the modem 40 via a cable. And a terminal 585 for connection to the terminal.
[0147]
The controller 510 executes the application program to receive the encrypted content data and the like from the distribution server 10 via the Internet 30 to the license management device 520 or the license management module 511. In addition to controlling data exchange, control is performed when encrypted content data and a license are obtained by ripping from a music CD via the CD-ROM drive 540.
[0148]
Further, the personal computer 50 exchanges various keys with the distribution server 10 when receiving the encrypted content data and the license from the distribution server 10 and reproduces the distributed encrypted content data. License management device 520 that manages the licenses in hardware and a program that is executed by the controller 510 and that receives the encrypted content data and the level 1 license from the distribution server 10 by the program, and receives the received license And a content management module 511 for generating a dedicated license with its own encryption.
[0149]
The license management device 520 is a device that performs hardware exchange of data when receiving encrypted content data and a license from the distribution server 10 and manages the received license in hardware, and therefore requires a high security level. Handles level 2 licenses. On the other hand, the license management module 511 performs software transmission and reception of data when receiving encrypted content data and a license from the distribution server 10 using a program executed by the stove and roller 510, and receives the license. In addition, since the encrypted content data for local use and the license are generated by ripping from the music CD, the obtained license is protected by performing encryption processing, etc., and stored and managed in the HDD 530. License management Only level 1 licenses with a security level lower than that of the device 520 are handled. Needless to say, if the high security level is level 2, a level 1 license can also be handled.
[0150]
As described above, the personal computer 50 uses the license management module 511 and the license management device 520 for receiving the encrypted content data and the license from the distribution server 10 via the Internet network 30, and the encrypted content data by ripping from the music CD. And a CD-ROM drive 540 for obtaining a license.
[0151]
FIG. 7 is a schematic block diagram for explaining the configuration of the playback terminal 100 shown in FIG.
[0152]
The playback terminal 100 gives the playback terminal 100 a bus BS3 for exchanging data of each part of the playback terminal 100, a controller 1106 for controlling the operation of the playback terminal 100 via the bus BS3, and an instruction from the outside. And a display panel 1110 for giving information output from the controller 1106 and the like as visual information to the mobile phone user.
[0153]
The playback terminal 100 further stores the content data (music data) from the distribution server 10 and exchanges data between the removable memory card 110 and the memory card 110 and the bus BS3 for decryption processing. A memory interface 1200 for controlling, a USB interface 1112 for controlling data exchange between the bus BS3 and the terminal 1114 when receiving encrypted content data and a license from the personal computer 50, and a USB cable 70 are connected. And a terminal 1114 for performing.
[0154]
The playback terminal 100 further authenticates its validity by decrypting the class public encryption key KPp1 and the class certificate Cp1 set for each type (class) of the playback terminal with the class public authentication key KPa. An authentication data holding unit 1500 that holds encrypted authentication data {KPp1 // Cp1} KPa2 is included. Here, it is assumed that the class y of the playback terminal 100 is y = 1. Further, since the playback terminal is a device that provides playback using a content playback device capable of maintaining confidentiality in hardware, the security level is level 2.
[0155]
The playback terminal 100 further includes a Kp1 holding unit 1502 that holds Kp1, which is a class secret decryption key of the playback terminal (content playback device), and a session generated by the memory card 110 by decrypting the data received from the bus BS3 with Kp1. A decryption processing unit 1504 for obtaining the key Ks2.
[0156]
The playback terminal 100 further provides a session key Ks3 for encrypting data exchanged with the memory card 110 on the bus BS3 in a playback session for playing back content data stored in the memory card 110, such as a random number. A session key generation unit 1508 generated by the above-described process, and a decryption processing unit that decrypts the session key Ks3 generated by the session key generation unit 1508 when receiving the license key Kc and the reproduction time limit ACp from the memory card 110 in the reproduction session of the encrypted content data. And an encryption processing unit 1506 that encrypts the session key Ks2 obtained by 1504 and outputs it to the bus BS3.
[0157]
Further, the playback terminal 100 decrypts the data on the bus BS3 with the session key Ks3 and outputs the license key Kc and the playback time limit ACp, and the encrypted content data {Dc} Kc from the bus BS3. A decryption processing unit 1516 that decrypts the license key Kc acquired from the decryption processing unit 1510 and outputs the content data; a music playback unit 1518 that receives the output of the decryption processing unit 1516 and plays back the content data; DA converter 1519 for converting the output of unit 1518 from a digital signal to an analog signal, and a terminal 1530 for outputting the output of DA converter 1519 to an external output device (not shown) such as a headphone.
[0158]
In FIG. 7, a region surrounded by a dotted line constitutes a content playback device 1550 that decrypts encrypted content data and plays back music data. In FIG. 7, for the sake of simplicity of explanation, only the blocks related to the reproduction of the music data of the present invention are described among the reproduction terminals, and some of the blocks relating to the call function that the reproduction terminal originally has are partially described. Is omitted.
[0159]
The operation of each component of the playback terminal 100 in each session will be described in detail later using a flowchart.
[0160]
FIG. 8 is a schematic block diagram for explaining the configuration of the memory card 110.
As described above, KPmw and Kmw are provided as the public encryption key and secret decryption key unique to the memory card, and the memory card class certificate Cmw is provided. In the memory card 110, the memory card class is It is assumed that a natural number w = 3 for identification and a natural number x = 4 for identifying a memory card, respectively. Further, since the memory card 110 is a device that keeps confidentiality in hardware, the security level is 2.
[0161]
Therefore, the memory card 110 has an authentication data holding unit 1400 that holds authentication data {KPm3 // Cm3} KPa2, and a Kmc holding unit that holds an individual secret decryption key Kmc4 that is a unique decryption key set for each memory card. 1402, a Km holding unit 1421 that holds a unique class secret decryption key Km3 set for each type of memory card, and a KPmc holding unit 1416 that holds a public encryption key KPmc4 that can be decrypted using the individual secret decryption key Kmc4. Including.
[0162]
As described above, by providing an encryption key for a recording device called a memory card, management of distributed content data and encrypted license keys can be executed in units of memory cards, as will be apparent from the following description. It becomes possible.
[0163]
The memory card 110 further includes an interface 1424 that exchanges signals with the memory interface 1200 via a terminal 1426, a bus BS4 that exchanges signals with the interface 1424, and data that is given to the bus BS4 from the interface 1424. The decryption processing unit 1422 that receives the class secret decryption key Km3 unique to each type of memory card from the Km holding unit 1421 and outputs the session key Ks1 generated by the distribution server 10 in the distribution session to the contact Pa, and KPa holding Receives the level 2 authentication key KPa2 from the unit 1414, executes the decryption process with the level 2 authentication key KPa2 from the data given to the bus BS4, and sends the decryption result and the obtained class certificate to the controller 1420. Key encryption processing unit 14 10 and an encryption processing unit 1406 that encrypts data selectively given by the changeover switch 1446 and outputs it to the bus BS4 with a key selectively given by the changeover switch 1442.
[0164]
The memory card 110 further includes a session key generation unit 1418 that generates a session key Ks2 in each session, and a session key Ks2 output from the session key generation unit 1418 by the class public encryption key KPpy or KPmw obtained by the decryption processing unit 1408. An encryption processing unit 1410 that encrypts and sends the data to the bus BS4; a decryption processing unit 1412 that receives data encrypted by the session key Ks2 from the bus BS4 and decrypts the data using the session key Ks2 obtained from the session key generation unit 1418; The individual public encryption key KPmc unique to the other memory card 110 decrypted by the decryption processing unit 1412 is used for the license key Kc and the playback time limit ACp read from the memory 1415 in the playback session of the encrypted content data. And a cryptographic processing unit 1417 for encrypting at (≠ 4).
[0165]
The memory card 110 further includes a decryption processing unit 1404 for decrypting data on the bus BS4 with the individual secret decryption key Kmc4 unique to the individual public encryption key KPmc4, the prohibited class list data CRL, Encrypted content data {Dc} Kc, license (Kc, ACp, ACm, license ID) for reproducing encrypted content data {Dc} Kc, additional information Data-inf, and playback list of encrypted content data And a memory 1415 for receiving and storing a license management file for managing licenses from the bus BS4. The memory 1415 is configured by a semiconductor memory, for example. The memory 1515 includes a CRL area 1415A for recording the prohibited class list CRL, a license area 1415B for recording a license, encrypted content data {Dc} Kc, related information Dc-inf of the encrypted content data, memory A playlist file that records basic information for accessing encrypted content data and licenses recorded on the card, and a license management file that records information necessary for managing licenses for each encrypted content data It consists of a data area 1415C that can be accessed directly from the outside. Details of the license management file and the playlist file will be described later.
[0166]
The license area 1415B stores a license in a license-dedicated recording unit called an entry for recording a license (content key Kc, reproduction control information ACp, access restriction information ACm, license ID). When accessing a license, the license is stored or an entry for which the license is to be recorded is designated by an entry number.
[0167]
Memory card 110 further includes a controller 1420 for exchanging data with the outside via bus BS4, receiving reproduction information from bus BS4, and controlling the operation of memory card 110. .
[0168]
All configurations except the data region 1415C are configured in a tamper resistant module region.
[0169]
FIG. 9 is a schematic block diagram showing the configuration of the license management device 520 built in the personal computer 50. The license management device 520 is fundamentally different in that it does not require an area corresponding to the data area 1415C in the memo card 110, and has an interface 5224 and a terminal 5226 that have different functions of the interface 1424 and different shapes of the terminals 1426. The memory card 110 has the same configuration. Authentication data holding unit 5200, Kmc holding unit 5202, decryption processing unit 5204, encryption processing unit 5206, decryption processing unit 5208, encryption processing unit 5210, decryption processing unit 5212, KPa holding unit 5214, KPmc holding unit 5216 of license management device 520 , An encryption processing unit 5217, a session key generation unit 5218, a controller 5220, a Km holding unit 5221, a decryption processing unit 5222, an interface 5224, a terminal 5226, and a changeover switch 5242 and 5246, respectively, an authentication data holding unit 1400 of the memory card 110, Kmc holding unit 1402, decryption processing unit 1404, encryption processing unit 1406, decryption processing unit 1408, encryption processing unit 1410, decryption processing unit 1412, KPa holding unit 1414, KPmc holding unit 1416, encryption processing unit 1417, session key Raw unit 1418, the controller 1420, Km holding unit 1421, decryption processing unit 1422 is the same as the change-over switch 1442,1446. However, the authentication data holding unit 5200 holds the authentication data {KPm7 // Cm7} KPa2, the KPmc holding unit 5216 holds the individual public encryption key KPm8, and the Km holding unit 5202 holds the class secret decryption key Km7. The Kmc holding unit 5221 holds the individual secret decryption key Kmc8. It is assumed that the natural number w representing the class of the license management device 520 is w = 7, and the natural number x for identifying the license management device 520 is x = 8.
[0170]
The license management device 520 includes a memory 5215 that records a prohibited class list CRL and a license (Kc, ACp, ACm, license ID) instead of the memory 1415 of the memory card 110. The memory 5215 includes a CRL area 5215A in which a prohibited class list CRL is recorded and a license area 5215B in which a license is recorded.
[0171]
Further, the license management device 520 needs to hold a binding license used by the license management module 511. Accordingly, the KPa holding unit 5214 holds the two authentication keys KPa2 and KPa1. Control from different levels will be described in detail later using flowcharts.
[0172]
Further, the license management module 511 is a program for managing licenses, and the security level is 1. Since the license management module 511 is a management program having almost the same configuration as the license management device 520, the natural number w representing the class of the license management module 511 is w = 5, and the natural number x for identifying the license management device 520 is x. Let x = 6. Therefore, the license management module 511 holds the authentication data {KPm5 // Cm5} KPa1, the individual public encryption key KPm6, the class secret decryption key Km5, and the individual secret decryption key Kmc6. Two authentication keys KPa2 and KPa1 are held.
[0173]
The operation of each session in the data distribution system shown in FIG. 1 will be described below.
[0174]
[Initialization]
Initialization performed before the personal computer 50 receives the encrypted content data and license from the distribution server 10 will be described.
[0175]
10 to 12 are first to third flowcharts for explaining initialization performed before the personal computer 50 receives the encrypted content data and the license from the distribution server 10.
[0176]
Referring to FIG. 10, when generation of a binding license is requested via the keyboard 560 (step S10), the license management module 511 generates a binding key Kb (step S12), and then transaction IDb, content IDb, predetermined control information ACmb and ACpb are generated (step S14). Steps S12 and S14 are binding license generation processing.
[0177]
Then, the license management module 511 instructs the license management device 520 to output authentication data via the bus BS2 (step S16).
[0178]
Then, the controller 5220 of the license management device 520 receives the authentication data output instruction via the terminal 5226, the interface 5224, and the bus BS5, and the authentication data {KPm7 // Cm7} from the authentication data holding unit 5200 via the bus BS5. KPa2 is acquired, and authentication data {KPm7 // Cm7} KPa2 is output via bus BS5, interface 5224, and terminal 5226 (step S18). The license management module 511 receives the authentication data {KPm7 // Cm7} KPa2 via the bus BS2 (step S20), and decrypts the authentication data {KPm7 // Cm7} KPa with the level 2 authentication key KPa2 (step S22). .
[0179]
The license management module 511 authenticates from the decryption processing result whether or not the processing has been performed normally, that is, the license management device 520 holds the public encryption key KPm7 and the certificate Cm7 from the authorized license management device. Therefore, an authentication process is performed to determine whether or not authentication data subjected to encryption for proving its validity is received by a legitimate institution (step S24). If it is determined that the authentication data is valid, the license management module 511 approves and accepts the public encryption key KPm7 and the certificate Cm7. Then, the process proceeds to the next process (step S26). If it is not valid authentication data, it is rejected, and the process is terminated without accepting the public encryption key KPm7 and the certificate Cm7 (step S68).
[0180]
If it is recognized as a legitimate device as a result of the authentication, the license management module 511 next determines whether the class certificate Cm7 of the license management device is listed in the prohibited class list CRL. In step S68, when these class certificates are included in the prohibited class list, the initialization ends here.
[0181]
On the other hand, if the class certificate of the license management device 520 is not included in the prohibited class list, the process proceeds to the next process (step S26).
[0182]
As a result of authentication, when it is confirmed that the access is from a license management device having valid authentication data and the class is not included in the prohibited class list, the license management module 511 generates a session key Ks2a (step S1). S28).
[0183]
Referring to FIG. 11, license management module 511 encrypts session key Ks2a with class public encryption key KPm7 to generate encrypted data {Ks2a} Km7 (step S30), and uses encrypted data {Ks2a} Km7 as a bus. The license is output to the license management device 520 via the BS 2 (step S32). The controller 5220 of the license management device 520 receives the encrypted data {Ks2a} Km7 via the terminal 5226, the interface 5224, and the bus BS5, and the decryption processing unit 5222 receives the class secret decryption key Km7 output from the Km holding unit 5221. To decrypt the encrypted data {Ks2a} Km7 and accept the session key Ks2a (step S34). The controller 5220 controls the session key generation unit 5218 to generate the session key Ks2b upon receiving the session key Ks2a. Then, the session key generating unit 5218 generates a session key Ks2b (step S36), and the controller 5220 acquires the update date / time CRLdate of the prohibited class list CRL from the CRL area 5215A of the memory 5215 via the bus BS5, and acquires it. The updated date / time CRLdate is output to the changeover switch 5246 via the bus BS5 (step S38). Then, the encryption processing unit 5206 encrypts the session key Ks2b, the individual public encryption key KPmc8, and the update date / time CRLdate received by sequentially switching the changeover switch 5246 with the session key Ks2a from the decryption processing unit 5222. The controller 5220 outputs the encrypted data {Ks2b // KPmc8 // CRLdate} Ks2a on the bus BS5 via the interface 5224 and the terminal 5226 (step S40).
[0184]
The license management module 511 receives the encrypted data {Ks2b // KPmc8 // CRLdate} Ks2a via the bus BS2, and decrypts the encrypted data {Ks2b // KPmc8 // CRLdate} Ks2a with the session key Ks2a. Ks2b, individual public encryption key KPmc8, and update date / time CRLdate are received (step S42). Then, the license management module 511 encrypts the binding license (transaction IDb, content IDb, binding key Kb, and control information ACmb, ACpb) generated in steps S12 and S14 with the public encryption key KPmc8, and encrypts the data {transaction IDb // Content IDb // Kb // ACmb // ACpb} Kmc8 is generated (step S44).
[0185]
Referring to FIG. 12, in license management module 511, the update date / time CRLdate of the prohibited class list transmitted from license management device 520 is changed from the update date / time of prohibited class list CRL held in hard disk (HDD) 530. It is compared whether the prohibited class list to be kept is new. When the prohibited class list CRL of the license management device 520 is newer, the process proceeds to step S48. Conversely, when the prohibited class list CRL of the license management module 511 is newer, the process proceeds to step S52 (step S46).
[0186]
When it is determined that the prohibited class list CRL of the license management device 520 is newer, the license management module 511 transfers the encrypted data {transaction IDb // content IDb // Kb // ACmb // ACpb} Kmc8 to the license management device. Encryption is performed using the session key Ks2b generated in 520, and the encrypted data {{transaction IDb // content IDb // Kb // ACmb // ACpb} Kmc8} Ks2b is output to the license management device 520 via the bus BS2. (Step S48).
[0187]
Then, the controller 5220 of the license management device 520 receives the encrypted data {{transaction IDb // content IDb // Kb // ACmb // ACpb} Kmc8} Ks2b via the terminal 5226 and the interface 5224, and a session key generation unit. It is decrypted by the session key Ks2b generated by 5218, and {transaction IDb // content IDb // Kc // ACmb // ACpb} Kmc8 is accepted (step S50). Thereafter, the process proceeds to step S60.
[0188]
On the other hand, when the license management module 511 determines that the prohibited class list CRL of the license management module 511 is newer, the license management module 511 updates the prohibited class list CRL held by the license management device 520, so that the bus Updates after the update date and time CRLdate are obtained as differential CRL from the HDD 530 via the BS 2 (step S52).
[0189]
Then, the license management module 511 generates the session key Ks2b generated in the license management device 520 by using the difference CRL of the prohibited class list and the encrypted data {transaction IDb // content IDb // Kb // ACmb // ACpb} Kmc8. The encrypted data {CRLdate // {transaction IDb // content IDb // Kb // ACmb // ACpb} Kmc8} Ks2b is output to the license management device 520 via the bus BS2 (step S54).
[0190]
The controller 5220 of the license management device 520 uses the decryption processing unit 5212 to decrypt the received data provided to the bus BS5 via the terminal 5226 and the interface 5224. Decryption processing unit 5212 decrypts the received data of bus BS5 using session key Ks2b given from session key generation unit 5218, and outputs the decrypted data to bus BS5 (step S56).
[0191]
At this stage, {transaction IDb // content IDb // Kb // ACmb // ACpb} Kmc8 that can be decrypted with the individual secret decryption key Kmc8 held in the Kmc holding unit 5221 and the differential CRL are stored in the bus BS5. Is output (step S56). The CRL area 5215A in the memory 5215 is updated based on the differential CRL with the differential CRL received by the instruction of the controller 5220 (step S58).
[0192]
Steps S48 and S50 are transmission operations to the license management device 520 such as the binding key Kb when the prohibited class list CRL of the license management device 520 on the receiving side is newer than the prohibited class list CRL of the license management module 511 on the transmitting side. Yes, steps S52, S54, S56, and S58 are a license management device such as a binding key Kb when the prohibited class list CRL of the license management module 511 on the transmission side is newer than the prohibited class list CRL of the license management device 520 on the reception side. This is a transmission operation to 520. In this way, the update date / time CRLdate of the prohibited class list sent from the license management device 520 is compared. When the prohibited class list CRL on the receiving side is older than the prohibited class list CRL on the transmitting side, the difference data of the prohibited class list is used. A certain differential CRL is acquired from the HDD 530, and the differential CRL is distributed to the license management device 520, so that a new prohibited class list CRL is always held.
[0193]
After step S50 or step S58, the encrypted data {transaction IDb // content IDb // Kb // ACmb // ACpb} Kmc8 is decrypted by the decryption processing unit 5204 with the secret decryption key Kmc8 according to the instruction of the controller 5220. The binding license (binding key Kb, transaction IDb, content IDb, control information ACmZ, ACp) is accepted (step S60).
[0194]
Then, the license management module 511 inputs the entry number “0” for storing the binding license to the license management device 520 (step S62), and the controller 5220 of the license management device 520 includes the terminal 5226, the interface 5224, and the bus. The entry number “0” is received via the BS 5, and a binding license (transaction IDb, content IDb, binding key Kb, control information is assigned to the area specified by the received entry number “0” in the license area 5215 B of the memory 5215. ACmb, ACpb) are stored (step S64).
[0195]
The license management module 511 confirms the area of the license management device 520 in order to record the binding key Kb and prepares for registration. A series of processes from step 16 in FIG. 10 to step 42 in FIG. The series of processing from step S44 in FIG. 11 to step S64 in FIG. 12 for storing the binding key Kb in the license area 5215B of the license management device 520 is referred to as “binding key registration processing”.
[0196]
On the other hand, the license management module 511 generates a plaintext confidential file with empty confidential information (level 1 license and checkout information), and generates an encrypted confidential file 160 obtained by encrypting the confidential file with the binding key Kb. The classified confidential file 160 is recorded in the HDD 530 (step S66), and the initialization operation is terminated (step S68).
[0197]
In this way, the license management module 511 of the personal computer 50 generates a binding license in the initialization operation, and in the area specified by the entry number “0” in the license area 5215B of the memory 5215 in the license management device 520. The generated binding license is stored, and an encrypted confidential file 160 obtained by encrypting the confidential file with the binding key Kb included in the generated binding license is generated. The encrypted confidential file 160 is for storing the license received from the distribution server 10 by the license management module 511. In addition, since the secret file is encrypted with the binding key Kb in this way, the license cannot be taken out from the encrypted secret file 160 without the binding key Kb, so the binding key Kb manages the license of the encrypted content data. It is a common key for Since the binding key Kb is stored in the memory 5215 of the license management device 520, the binding key Kb can be managed by hardware. As a result, the license of the encrypted content data managed in software by the encrypted confidential file 160 recorded in the HDD 530 via the binding key Kb is managed by hardware. Therefore, as will be described later, the encrypted content data and license received by the software can be transferred to another personal computer 80.
[0198]
[Distribution 1]
Next, in the data distribution system shown in FIG. 1, an operation for distributing encrypted content data and a level 2 license for requesting security level 2 from the distribution server 10 to the license management device 520 of the personal computer 50 will be described. This operation is referred to as “distribution 1”.
[0199]
FIGS. 13 to 16 illustrate a distribution operation (hereinafter also referred to as a distribution session) to the license management device 520 built in the personal computer 50 that occurs when the encrypted content data is purchased in the data distribution system shown in FIG. It is the 1st-4th flowchart for this.
[0200]
Prior to the processing in FIG. 13, it is assumed that the user of the personal computer 50 is connected to the distribution server 10 via the modem 40 and has acquired the content ID for the content desired to be purchased.
[0201]
Referring to FIG. 13, a distribution request is made by the user of personal computer 50 by designating a content ID via keyboard 560 (step S100). Then, purchase conditions AC for purchasing the license of the encrypted content data are input via the keyboard 560 (step S102). That is, in order to purchase the license key Kc for decrypting the selected encrypted content data, the access condition information ACm of the encrypted content data and the reproduction time limit ACp are set and the purchase condition AC is input.
[0202]
When the purchase condition AC for the encrypted content data is input, the controller 510 gives an instruction to output the authentication data to the license management device 520 via the bus BS2 (step S104). The controller 5220 of the license management device 520 receives the authentication data output instruction via the terminal 5226, the interface 5224, and the bus BS5. Controller 5220 reads authentication data {KPm7 // Cm7} KPa2 from authentication data holding unit 5200 via bus BS5, and outputs {KPm7 // Cm7} KPa2 via bus BS5, interface 5224 and terminal 5226. (Step S106).
[0203]
The controller 510 of the personal computer 50 transmits the content ID, the license purchase condition data AC, and the distribution request to the distribution server 10 in addition to the authentication data {KPm7 // Cm7} KPa2 from the license management device 520 ( Step S108).
[0204]
The distribution server 10 receives the distribution request, content ID, authentication data {KPm7 // Cm7} KPa2, and license purchase condition data AC from the personal computer 50 (step S110), and the decryption processing unit 312 receives the license management device 520 from the license management device 520. The output authentication data is decrypted with the level 2 authentication key KPa (step S112).
[0205]
The distribution control unit 315 performs an authentication process that determines whether or not authentication data subjected to encryption for proving its validity has been received from the decryption processing result in the decryption processing unit 312 (step S114). ). If it is determined that the authentication data is valid, the distribution control unit 315 approves and accepts the class public encryption key KPm7 and the class certificate Cm7. Then, the process proceeds to the next process (step S116). If it is not legitimate authentication data, it is rejected, and the distribution session is terminated without accepting the class public encryption key KPm7 and the class certificate Cm7 (step S198). If a distribution request is made from level 1, the level 2 authentication key KPa2 cannot authenticate the level 1 authentication data, and the process ends here.
[0206]
As a result of the authentication, if it is legitimate authentication data and the class public encryption key KPm7 and the class certificate Cm7 are approved, the distribution control unit 315 next places the class certificate Cm7 of the license management device in the prohibited class list CRL. The CRL database 306 is inquired as to whether it is listed, and if these class certificates are included in the prohibited class list, the distribution session is terminated here (step S198).
[0207]
On the other hand, if the class certificate of the license management device 520 is not included in the prohibited class list, the process proceeds to the next process (step S116).
[0208]
As a result of authentication, when it is confirmed that the access is from a personal computer including a license management device having valid authentication data and the class is not included in the prohibited class list, the distribution control unit 315 in the distribution server 10 Then, a transaction ID which is a management code for specifying the distribution is generated (step S118). In addition, the session key generation unit 316 generates a session key Ks1 for distribution (step S120). The session key Ks1 is encrypted by the encryption processing unit 318 with the class public encryption key KPm7 corresponding to the license management device 520 obtained by the decryption processing unit 312 (step S122).
[0209]
The transaction ID and the encrypted session key Ks1 are output to the outside as the transaction ID // {Ks1} Km7 via the bus BS1 and the communication device 350 (step S124).
[0210]
Referring to FIG. 14, when personal computer 50 receives transaction ID // {Ks1} Km7 (step S126), controller 510 inputs transaction ID // {Ks1} Km7 to license management device 520 (step S126). S128). Then, in the license management device 520, the decryption processing unit 5222 sends the received data given to the bus BS 5 via the terminal 5226 and the interface 5224 to the license management device 520 held in the holding unit 5221. By decrypting with Km7, the session key Ks1 is decrypted and the session key Ks1 is accepted (step S130).
[0211]
When the controller 5220 confirms acceptance of the session key Ks1 generated by the distribution server 10, the controller 5220 instructs the session key generation unit 5218 to generate the session key Ks2 generated during the distribution operation in the license management device 520. Session key generation unit 5218 generates session key Ks2 (step S132).
[0212]
In the distribution session, the controller 5220 extracts the update date / time CRLdate from the prohibited class list CRL recorded in the memory 5215 in the license management device 520 from the memory 1415 and outputs it to the changeover switch 5246 (step S134).
[0213]
The encryption processing unit 5206 uses the session key Ks1 given from the decryption processing unit 5222 via the contact Pa of the changeover switch 5242 to sequentially switch the contact of the changeover switch 5246, the session key Ks2, the individual public encryption key KPmc8, and The update date / time CRLdate of the prohibited class list is encrypted as one data string, and {Ks2 // KPmc8 // CRLdate} Ks1 is output to the bus BS3 (step S136).
[0214]
The encrypted data {Ks2 // KPmc8 // CRLdate} Ks1 output to the bus BS3 is output from the bus BS3 to the personal computer 50 via the interface 5224 and the terminal 5226, and transmitted from the personal computer 50 to the distribution server 10. (Step S138).
[0215]
The distribution server 10 receives the transaction ID // {Ks2 // KPmc8 // CRLdate} Ks1, executes decryption processing with the session key Ks1 in the decryption processing unit 320, and generates the session key Ks2 generated by the license management device 520. Then, the individual public encryption key KPmc8 unique to the license management device 520 and the update date / time CRLdate of the prohibited class list in the license management device 520 are received (step S142).
[0216]
The distribution control unit 315 generates the access restriction information ACm and the reproduction time limit ACp according to the content ID and the license purchase condition AC acquired in step S110 (step S144). Further, a license key Kc for decrypting the encrypted content data is acquired from the information database 304 (step S146).
[0217]
The distribution control unit 315 gives the generated license, that is, the transaction ID, content ID, license key Kc, reproduction time limit ACp, and access restriction information ACm to the encryption processing unit 326. The encryption processing unit 326 encrypts the license with the individual public encryption key KPmc8 unique to the license management device 520 obtained by the decryption processing unit 320, and generates encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc8 is generated (step S148).
[0218]
Referring to FIG. 15, distribution server 10 compares the update date / time CRLdate of the prohibited class list transmitted from license management device 520 with the update date / time of prohibited class list CRL of distribution server 10 held in CRL database 306. Thus, the license management device 520 determines whether or not the prohibited class list CRL that is held is the latest, and when it is determined that it is the latest, the process proceeds to step S152. If it is not the latest, the process proceeds to step S160 (step S150).
[0219]
When it is determined that the data is latest, the encryption processing unit 328 uses the encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc8 output from the encryption processing unit 326 in the license management device 520. Encryption is performed using the generated session key Ks2, and the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc8} Ks2 is output to the bus BS1. Then, the distribution control unit 315 transmits the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc8} Ks2 on the bus BS1 to the personal computer 50 via the communication device 350 ( Step S152).
[0220]
Then, the controller 510 of the personal computer 50 receives the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc8} Ks2 (step S154), and the license management device via the bus BS5. Input to 520. The decryption processing unit 5212 of the license management device 520 receives the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc8} Ks2 via the terminal 5226 and the interface 5224, and a session key generation unit. It is decrypted with the session key Ks2 generated by 5218, and {transaction ID // content ID // Kc // ACm // ACp} Kmc8 is accepted (step S158). Thereafter, the process proceeds to step S172.
[0221]
On the other hand, if it is determined that it is not the latest, the distribution control unit 315 obtains the latest prohibited class list CRL from the CRL database 306 via the bus BS1, and generates a differential CRL that is differential data (step S160).
[0222]
The encryption processing unit 328 receives the output of the encryption processing unit 326 and the difference CRL of the prohibited class list supplied by the distribution control unit 315 via the bus BS1, and generates the session key Ks2 generated in the license management device 520. Encrypt with The encrypted data {difference CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc8} Ks2 output from the encryption processing unit 328 is stored in the personal computer via the bus BS1 and the communication device 350. 50 (step S162).
[0223]
The personal computer 50 receives the transmitted encrypted data {difference CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc8} Ks2 (step S164) and licenses it via the bus BS5. The data is input to the management device 520 (step S166). In the license management device 520, the reception data given to the bus BS 5 is decrypted by the decryption processing unit 5212 via the terminal 5226 and the interface 5224. Decryption processing unit 5212 decrypts the received data of bus BS5 using session key Ks2 given from session key generation unit 5218, and outputs the decrypted data to bus BS5 (step S168).
[0224]
At this stage, the bus BS5 has an encryption license {transaction ID // content ID // Kc // ACm // ACp} Kmc8} that can be decrypted with the secret decryption key Kmc8 held in the Kmc holding unit 5221, and the difference. CRL is output (step S168). The CRL area 5215A in the memory 5215 is updated based on the difference CRL with the difference CRL received by the instruction of the controller 5220 (step S170).
[0225]
Steps S152, S154, S156, and S158 are operations for distributing the license key Kc and the like to the license management device 520 when the prohibited class list CRL held by the license management device 520 is the latest, and steps S160, S162, S164, and S166. , S168, and S170 are operations for distributing the license key Kc and the like to the license management device 520 when the prohibited class list CRL held by the license management device 520 is not the latest. In this way, it is checked one by one whether the update date / time CRLdate of the prohibited class list sent from the license management device 520 is the latest update date / time, and when it is not the latest, the latest prohibited class list CRLdate is read from the CRL database 306. By acquiring and distributing the differential CRL to the license management device 520, it is possible to prevent outflow of the distributed license to the license management device whose license has been broken.
[0226]
After step S158 or step S170, the encryption license {transaction ID // content ID // Kc // ACm // ACp} Kmc8 is decrypted by the individual secret decryption key Kmc8 in the decryption processing unit 5204 according to the instruction of the controller 5220. Then, the license (license key Kc, transaction ID, content ID, access restriction information ACm, and reproduction time limit ACp) is accepted (step S172).
[0227]
Referring to FIG. 16, controller 510 inputs an entry number for instructing an entry for storing a license received by license management device 520 to license management device 520 (step S174). Then, the controller 5220 of the license management device 520 receives the entry number via the terminal 5226 and the interface 5224, and stores the license (license key) acquired in step S172 in the license area 5215B of the memory 5215 specified by the received entry number. Kc, transaction ID, content ID, access restriction information ACm, and reproduction time limit ACp) are stored (step S176).
[0228]
The controller 510 of the personal computer 50 transmits the transaction ID sent from the distribution server 10 and the distribution request for encrypted content data to the distribution server 10 (step S178).
[0229]
The distribution server 10 receives the transaction ID and the encrypted content data distribution request (step S180), acquires the encrypted content data {Dc} Kc and the additional information Dc-inf from the information database 304, and receives these data. Is output via the bus BS1 and the communication device 350 (step S182).
[0230]
The personal computer 50 receives {Dc} Kc // Dc-inf and accepts the encrypted content data {Dc} Kc and the additional information Dc-inf (step S184). Controller 510 then records encrypted content data {Dc} Kc and additional information Dc-inf as one content file on hard disk (HDD) 530 via bus BS2 (step S186). Further, the controller 510 generates a license management file for the encrypted entry data {Dc} Kc and additional information Dc-inf including the license entry number stored in the license management device 520, the plaintext transaction ID and the content ID. The data is recorded in the HDD 530 via the bus BS2 (step S188). Furthermore, the controller 510 uses the information on the encrypted content data extracted from the name of the recorded content file and license management file and the additional information Dc-inf as the content information received in the content list file recorded in the HDD 530 ( The music title, artist name, etc. are added (step S190), and the transaction ID and delivery acceptance are transmitted to the delivery server 10 (step S192).
[0231]
Upon receiving the transaction ID // delivery acceptance (step S194), the distribution server 10 stores the charging data in the charging database 302 and records the transaction ID in the distribution record database 308 to execute the distribution end process. (Step S196), and the entire process ends (Step S198).
[0232]
In this way, the license management device 50 built in the personal computer 50 is a device that holds regular authentication data, and at the same time, the public encryption key KPm7 that can be encrypted and transmitted together with the class certificate Cm7 is valid. After confirming that the class certificate Cm7 is content only for a distribution request from a license management device not listed in the prohibited class list, that is, the class certificate list whose encryption with the public encryption key KPm7 is broken. Data can be distributed, and distribution to an unauthorized license management device and distribution using a decrypted class key can be prohibited.
[0233]
In addition, the encryption keys generated by the distribution server and the license management device are exchanged, encryption is performed using the encryption keys received by each other, and the encrypted data is transmitted to the other party. In fact, mutual authentication can be performed in the transmission / reception of digitized data, and the security of the data distribution system can be improved.
[0234]
Further, when receiving the encrypted content data and the license from the distribution server 10, the license management device 520 exchanges data with the distribution server 10 in hardware and reproduces the encrypted content data. Is stored in hardware, so its security level is high. Therefore, if the license management device 520 is used, the personal computer 50 can receive encrypted content data and a license by distribution with a high security level, and can manage a level 2 license with a high security level.
[0235]
[Distribution 2]
An operation of distributing encrypted content data and a license from the distribution server 10 to the license management module 511 of the personal computer 50 in the data distribution system shown in FIG. 1 will be described. This operation is referred to as “distribution 2”.
[0236]
17 to 21 illustrate first to fifth distribution operations for explaining the distribution operation to the license management module 511 built in the personal computer 50 that occurs when the encrypted content data is purchased in the data distribution system shown in FIG. It is a flowchart. The license management module 511 executes reception of encrypted content data and a license from the distribution server 10 by a program.
[0237]
Prior to the processing in FIG. 17, it is assumed that the user of the personal computer 50 is connected to the distribution server 10 via the modem 40 and acquires the content ID for the content desired to be purchased.
[0238]
Referring to FIG. 17, a distribution request is made by the user of personal computer 50 by designating the content ID via keyboard 560 (step S200). Then, purchase conditions AC for purchasing the license of the encrypted content data are input via the keyboard 560 (step S202). That is, in order to purchase the license key Kc for decrypting the selected encrypted content data, the access condition information ACm of the encrypted content data and the reproduction time limit ACp are set and the purchase condition AC is input.
[0239]
When the encrypted content data purchase condition AC is input, the controller 510 reads the authentication data {KPm5 // Cm5} KPa2 from the license management module 511, and in addition to the read authentication data {KPm5 // Cm5} KPa2. The content ID, the license purchase condition data AC, and the distribution request are transmitted to the distribution server 10 (step S204).
[0240]
The distribution server 10 receives the distribution request, content ID, authentication data {KPm5 // Cm5} KPa2, and license purchase condition data AC from the personal computer 50 (step S206), and the decryption processing unit 312 receives the license management module 511 from the license management module 511. The output authentication data is decrypted with the level 1 authentication key KPa1 (step S208).
[0241]
The distribution control unit 315 determines from the decryption processing result in the decryption processing unit 312 whether or not the processing has been normally performed, that is, to verify the validity of the class public encryption key KPm5 and the class certificate Cm5 at a legitimate organization. An authentication process for determining whether or not encrypted authentication data has been received is performed (step S210). If it is determined that the authentication data is valid, the distribution control unit 315 approves and accepts the class public encryption key KPm5 and the class certificate Cm5. Then, the process proceeds to the next process (step S212). If it is not valid authentication data, it is rejected and the process is terminated without accepting the class public encryption key KPm5 and the class certificate Cm5 (step S288).
[0242]
When it is recognized that the module is a legitimate module as a result of the authentication, the distribution control unit 315 next determines whether or not the class certificate Cm5 of the license management module 511 is listed in the prohibited class list CRL. If these class certificates are included in the prohibited class list, the distribution session ends here (step S288).
[0243]
On the other hand, if the class certificate of the license management module 511 is not included in the prohibited class list, the process proceeds to the next process (step S214).
[0244]
As a result of authentication, when it is confirmed that the access is from a personal computer including a license management module having valid authentication data and the class is not included in the prohibited class list, the distribution control unit 315 in the distribution server 10 Then, a transaction ID which is a management code for specifying the distribution is generated (step S214). In addition, the session key generation unit 316 generates a session key Ks1 for distribution (step S216). The session key Ks1 is encrypted by the encryption processing unit 318 with the class public encryption key KPm5 corresponding to the license management module 511 obtained by the decryption processing unit 312 (step S218).
[0245]
The transaction ID and the encrypted session key Ks1 are output to the outside as the transaction ID // {Ks1} Km5 via the bus BS1 and the communication device 350 (step S220).
[0246]
Referring to FIG. 18, when controller 510 of personal computer 50 receives transaction ID // {Ks1} Km5 (step S222), license management module 511 receives {Ks1} Km5 and sends it to license management module 511. Decryption processing is performed with the unique class secret decryption key Km5, and the session key Ks1 is accepted (step S224).
[0247]
Upon confirming acceptance of the session key Ks1 generated by the distribution server 10, the license management module 511 generates a session key Ks2 (step S226). Then, the controller 510 reads the encrypted CRL stored in the HDD 530 via the bus BS2, and the license management module 511 obtains the prohibited class list CRL by decrypting the encrypted CRL, and adds it to the decrypted prohibited class list CRL. Based on this, the update date / time CRLdate of the prohibited class list is acquired (step S228). Further, the license management module 511 uses the session key Ks1 generated in the distribution server 10 as a data string for the session key Ks2, the individual public encryption key KPmc6 generated by the license management module 511, and the data CRLdate of the prohibited class list. Encrypt and output {Ks2 // KPmc6 // CRLdate} Ks1 (step S230).
[0248]
The controller 510 transmits the transaction ID // {Ks2 // KPmc6 // CRLdate} Ks1 obtained by adding the transaction ID to the encrypted data {Ks2 // KPmc6 // CRLdate} Ks1 to the distribution server 10 (step S232).
[0249]
The distribution server 10 receives the transaction ID // {Ks2 // KPmc6 // CRLdate} Ks1 (step S234), performs decryption processing with the session key Ks1 in the decryption processing unit 320, and is generated by the license management module 511. The session key Ks2, the individual public encryption key KPmc6 unique to the license management module 511, and the update date / time CRLdate of the prohibited class list in the license management module 511 are received (step S236).
[0250]
The distribution control unit 315 generates the access restriction information ACm and the reproduction time limit ACp according to the content ID and the license purchase condition data AC acquired in step S206 (step S238). Further, a license key Kc for decrypting the encrypted content data is acquired from the information database 304 (step S240).
[0251]
The distribution control unit 315 gives the generated license, that is, the transaction ID, content ID, license key Kc, reproduction time limit ACp, and access restriction information ACm to the encryption processing unit 326. The encryption processing unit 326 encrypts the license with the individual public encryption key KPmc6 unique to the license management module 511 obtained by the decryption processing unit 320, and generates encrypted data {transaction ID // content ID // Kc // ACm / / ACp} Kmc6 is generated (step S242).
[0252]
Referring to FIG. 19, distribution server 10 determines whether or not the prohibited class list CRL of license management device 520 that has requested distribution is the latest, based on the update date and time CRLdate of the prohibited class list transmitted from license management module 511. If it is determined that the prohibited class list CRL of the license management module is the latest, the process proceeds to step S246. On the other hand, when it is determined that it is not the latest, the process proceeds to step S252 (step S244).
[0253]
When it is determined that the data is latest, the encryption processing unit 328 uses the encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc6 output from the encryption processing unit 326 in the license management module 511. Encryption is performed using the generated session key Ks2, and the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc6} Ks2 is output to the bus BS1. Then, the distribution control unit 315 transmits the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc6} Ks2 on the bus BS1 to the personal computer 50 via the communication device 350 ( Step S246).
[0254]
The controller 510 of the personal computer 50 receives the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc6} Ks2 (step S248), and the license management module 511 receives the encrypted data. Data {{transaction ID // content ID // Kc // ACm // ACp} Kmc6} Ks2 is decrypted with session key Ks2, and {transaction ID // content ID // Kc // ACm // ACp} Kmc6 is accepted. (Step S250). Thereafter, the process proceeds to step S262.
[0255]
On the other hand, if it is determined that it is not the latest, the distribution control unit 315 obtains the latest prohibited class list CRL from the CRL database 306 via the bus BS1, and generates a differential CRL that is differential data (step S252).
[0256]
The encryption processing unit 328 receives the output of the encryption processing unit 326 and the difference CRL of the prohibited class list supplied by the distribution control unit 315 via the bus BS1, and generates the session key Ks2 generated in the license management module 511. Encrypt with The encrypted data {difference CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc6} Ks2 output from the encryption processing unit 328 is stored in the personal computer via the bus BS1 and the communication device 350. 50 (step S254).
[0257]
The personal computer 50 receives the transmitted encrypted data {difference CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc6} Ks2 (step S256), and the license management module 511 The received data is decrypted using session key Ks2 and accepted as differential CRL and encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc6 (step S258).
[0258]
The controller 510 adds the accepted differential CRL to the prohibited class list CRL recorded in the HDD 530, performs original encryption processing, and rewrites the prohibited class list CRL in the HDD 530 (step S260).
[0259]
In steps S246, S248, and S250, the license class management module 511 manages the license when the prohibited class list CRL managed by the license management module 511 is the latest, based on the update date / time CRLdate of the prohibited class list sent from the license management module 511. Steps S252, S254, S256, S258, and S260 are operations for distributing a license to the license management module 511 when the prohibited class list CRL is not the latest. In this way, it is checked one by one whether the prohibited class list CRL of the license management device 520 that has requested distribution is the latest, based on the update date / time CRLdate of the prohibited class list sent from the license management module 511, and is not the latest. When the latest prohibited class list CRL is acquired from the CRL database 306 and the differential CRL is distributed to the license management module 511, the license distributed to the license management module is prevented from being leaked to a device whose security has been broken. it can.
[0260]
After step S250 or step S260, the encrypted license {transaction ID // content ID // Kc // ACm // ACp} Kmc6 is decrypted by the individual secret decryption key Kmc6, and the license (license key Kc, transaction ID, content) ID, access restriction information ACm, and reproduction time limit ACp) are accepted (step S262).
[0261]
In this way, by exchanging the encryption keys generated respectively by the distribution server and the license management module, performing encryption using the encryption keys received by each other, and transmitting the encrypted data to the other party, Even in the transmission / reception of the encrypted data, the mutual authentication can be effectively performed and the security of the data distribution system can be improved.
[0262]
The license management module 511 determines whether or not the number of reproductions is restricted by the received access restriction information ACm. If the number of reproductions is not restricted, the license management module 511 proceeds to step S266, and if the number of reproductions is restricted, step S268. (Step S264). When the number of times of reproduction is not limited, the license management module 511 generates checkout information including the number of checkouts that can be lent out to the other device for the encrypted content and license received from the distribution server 10 ( Step S266). In this case, the initial value of checkout is set to “3”. When the number of reproductions is limited, the license management module 511 generates checkout information by setting the number of possible checkouts for renting the encrypted content data to another device to “0” (step S268). Step S268 is processing for preventing the number of reproductions from being managed by checking out.
[0263]
Referring to FIG. 20, after step S266 or step S268, license management module 511 outputs authentication data {KPm5 // Cm5} KPa1 to license management device 520 via bus 2 (step S270). The license management device 520 receives the authentication data {KPm5 // Cm5} KPa1 from the license management module 511, and the decryption processing unit 5208 receives the authentication data authentication data {KPm5 // Cm5} KPa1 and receives the authentication data authentication data { Based on KPm5 // Cm5} KPa1, level 1 authentication key KPa1 is received from KPa holding unit 5214, and authentication data {KPm5 // Cm5} KPa1 is decrypted using received level 1 authentication key KPa1 (step S271).
[0264]
The controller 5220 determines from the decryption processing result in the decryption processing unit 5208 whether or not the processing has been normally performed, that is, a cipher for proving the validity of the class public encryption key KPm5 and the class certificate Cm5 at a legitimate organization. Authentication processing is performed to determine whether or not the authentication data subjected to has been received (step S272). If it is determined that the authentication data is valid, the controller 5220 approves and accepts the class public encryption key KPm5 and the class certificate Cm5. Then, the process proceeds to the next process (step S273). If it is not valid authentication data, it is rejected, and the process is terminated without accepting the class public encryption key KPm5 and the class certificate Cm5 (step S298).
[0265]
As a result of authentication, if it is recognized that regular authentication data has been received, the controller 5220 next determines whether or not the class certificate Cm5 of the license management module 511 is listed in the prohibited class list CRL. The CRL area 5215A is inquired, and if these class certificates are the subject of the prohibited class list, the distribution session is terminated here (step S298).
[0266]
On the other hand, if the class certificate of the license management module 511 is not included in the prohibited class list, the process proceeds to the next process (step S273).
[0267]
As a result of authentication, when it is confirmed that the access is from the license management module 511 including the license management device having valid authentication data and the class is not included in the prohibited class list, the license management device 520 The generation unit 5208 generates a session key Ks2a (step S274), and the encryption processing unit 5210 encrypts the session key Ks2a with the class public encryption key KPm5 and outputs encrypted data {Ks2a} Km5 (step S275).
[0268]
The controller 5220 outputs the encrypted data {Ks2a} Km5 via the bus BS5, the interface 5224, and the terminal 5226, and the license management module 511 receives the encrypted data {Ks2a} Km5 via the bus BS2. The encrypted data {Ks2a} Km5 is decrypted with the secret decryption key Km5 and the session key Ks2a is accepted (step S276). Then, the license management module 511 generates a session key Ks2b (step S277), encrypts the session key Ks2b with the session key Ks2a, and outputs the encrypted data {Ks2b} Ks2a to the license management device 520 via the bus BS2. (Step S278).
[0269]
The controller 5220 of the license management device 520 receives the encrypted data {Ks2b} Ks2a via the terminal 5226, the interface 5224, and the bus BS5, and the decryption processing unit 5212 receives the session key Ks2a output from the session key generation unit 5208. The encrypted data {Ks2b} Ks2a is decrypted and the session key Ks2b is accepted (step S279). Then, the license management module 511 inputs the entry number “0” to the license management device 520 (step S280), and the controller 5220 of the license management device 520 enters the entry number “0” via the terminal 5226, the interface 5224, and the bus BS5. 0 ”is received. The controller 5220 then binds the binding license (transaction IDb, content IDb, binding key Kb, and control information ACmb, ACpb stored in the area specified by the entry number “0” in the license area 5215B of the memory 5215. ) Is acquired (step S281). Then, the controller 5220 determines whether or not the binding license is valid based on the control information ACmb. If the binding license is not valid, the controller 5220 moves to step S298 and ends the distribution session. Here, the valid case means that the number of reproductions in the control information ACmb is not 0, and that the security level of the control information ACmb is level 1 because the process is authenticated by the level 1 authentication key KPa1. To do.
[0270]
On the other hand, if the binding license is valid, the process proceeds to step S283 (step S282).
[0271]
If it is determined in step S282 that the binding license is valid, the encryption processing unit 5206 decrypts the binding key Kb and the control information ACpb acquired via the changeover switch 5246 by the decryption processing unit 5212 and passes through the switch 5242. The encrypted data {Kb // ACpb} Ks2b is output after being encrypted with the acquired session key Ks2b (step S283).
[0272]
Referring to FIG. 21, controller 5220 outputs encrypted data {Kb // ACpb} Ks2b via bus BS5, interface 5224, and terminal 5226, and license management module 511 encrypts the data via bus BS2. Data {Kb // ACpb} Ks2b is received, and encrypted data {Kb // ACpb} Ks2b is decrypted with session key Ks2b to obtain binding key Kb and control information ACpb (step S284).
[0273]
A series of processing from step S270 to step S284 is processing for acquiring the binding key Kb from the license management device 520, and is collectively referred to as “binding key acquisition processing”.
[0274]
Then, the license management module 511 acquires the encrypted confidential file 160 from the HDD 530 via the bus BS2, and decrypts the acquired encrypted confidential file 160 with the binding key Kb to acquire a plaintext confidential file (step S285). ). Then, the license management module 511 receives the license (transaction ID, content ID, license key Kc, access restriction information ACm, and reproduction time limit ACp) received from the distribution server 10 and the chuck-out information generated in step S266 or step S268. Is added to the plaintext confidential file as confidential information n (step S286). Thereafter, the license management module 511 re-encrypts the plaintext confidential file with the binding key Kb, and updates the encrypted confidential file 160 recorded in the HDD 530 with the encrypted encrypted confidential file 160 (step S287). After storing the license in the encrypted confidential file 160, the license management module 511 transmits the transaction ID sent from the distribution server 10 and the distribution request for the encrypted content data to the distribution server 10 (step S288).
[0275]
The distribution server 10 receives the transaction ID and the encrypted content data distribution request (step S289), acquires the encrypted content data {Dc} Kc and the additional information Dc-inf from the information database 304, and receives these data. Is output via the bus BS1 and the communication device 350 (step S290).
[0276]
The license management module 511 receives {Dc} Kc // Dc-inf and accepts the encrypted content data {Dc} Kc and the additional information Dc-inf (step S291). Then, the license management module 511 records the encrypted content data {Dc} Kc and the additional information Dc-inf as content files on the hard disk (HDD) 530 via the bus BS2 (step S292). The license management module 511 also includes a content file (encrypted content data {Dc} Kc and additional information) including the confidential information number n of the confidential information n stored in the encrypted confidential file 160 and the plaintext transaction ID and content ID. A license management file corresponding to (Dc-inf) is generated and recorded in the HDD 530 via the bus BS2 (step S293). Further, the license management module 511 receives the content information received in the content list file recorded in the HDD 530, and information on the recorded content file and the name of the license management file and the encrypted content data extracted from the additional information Dc-inf. (Song title, artist name) and the like are added (step S294), and the transaction ID and distribution acceptance are transmitted to the distribution server 10 (step S295).
[0277]
When the distribution server 10 receives the transaction ID // distribution acceptance (step S296), the distribution server 10 stores the charging data in the charging database 302 and records the transaction ID in the distribution record database 308 to execute the distribution end process. (Step S297), and the entire process is completed (Step S298).
[0278]
As described above, the license management module 511 exchanges data with the distribution server 10 by software, and receives the encrypted content data and the license from the distribution server 10 in software. The received encrypted content data is recorded in the HDD 530, the license is written in the confidential file as confidential information n, the confidential file is encrypted with the binding key Kb, and the license is stored in the encrypted confidential file 160. Then, the binding key Kb for decrypting the encrypted confidential file 160 is held in the license management device 520. Therefore, the distribution of the encrypted content data and license by the license management module 511 is lower in security level than the distribution of the encrypted content data and license by the license management device 520, but is not associated with the personal computer 50 in the record management. It will be close to that.
[0279]
[Ripping]
The user of the personal computer 50 can acquire and use the music data from the music CD that he owns in addition to acquiring the encrypted content and license by distribution. Digital copying of music CDs is not free from the standpoint of copyright holders' rights protection, but individuals can copy music using tools with copyright protection functions for their own purposes. It is allowed to enjoy. Therefore, the license management module 511 also includes a program that implements a ripping function for acquiring music data from a music CD and generating encrypted content data that can be managed by the license management module 511 and a license.
[0280]
Some recent music CDs have electronic watermarks called watermarks inserted into the music data. In this watermark, a copyright owner writes a range of usage by the user as a usage rule. When ripping from music data in which usage rules are written, it is necessary to follow these usage rules from the viewpoint of copyright protection. Hereinafter, it is assumed that the replication conditions (duplication prohibition / one-generation replication permitted / replicatable) and the maximum number of checkouts are described as usage rules. Further, when the watermark is not detected, that is, the usage rules are written. In order to protect the rights of the copyright holder, even a conventional music CD that does not exist can be copied one generation, and the maximum checkout number is interpreted as “3”.
[0281]
With reference to FIGS. 22 to 24, acquisition of encrypted content data and a license by ripping from a music CD on which music data is recorded will be described.
[0282]
22 to 24 are first to third flowcharts for acquiring encrypted content data and a license by ripping from a music CD.
[0283]
Referring to FIG. 22, when the ripping operation is started, the music data detected by CD-ROM drive 540 from the music CD is fetched, and the usage rule described by the watermark is detected from the fetched music data. (Step S700). Then, it is determined whether or not copying is possible based on the detected usage rule (step S701). If the duplication condition of the usage rule is unlimited, the process proceeds to step S203. If the duplication condition is one-generation duplication, the process proceeds to step S702. If the duplication condition is copy prohibition, the duplication is prohibited, and the process proceeds to step S733. The operation ends. Further, if the mounted CD does not include a watermark and the usage rule cannot be obtained, the process proceeds to step S705.
[0284]
In step S701, when the copy rule of the usage rule is one-generation duplication, the license management module 511 replaces the watermark included in the acquired music data with the watermark changed to the copy prohibited copy rule of the acquired usage rule. (Step S702). Then, the process proceeds to step S703. When a usage rule that can be duplicated is detected, in step S703, the license management module 511 generates access restriction information ACm and reproduction time limit ACp reflecting the usage rule (step S703). Again, according to the replication conditions, if replication is possible, the mobile replication flag of the access restriction information ACm is set to mobile replication possible (= 3). If one generation replication is possible, the ripping itself corresponds to one generation. Set to prohibited (= 0). There is no corresponding usage rule, but the number of playbacks is unlimited, and the security level is set to level 1. Thereafter, the license management module 511 sets the number of possible checkouts by reflecting the maximum number of checkouts in the usage rule. If the maximum number of checkouts is not specified, the number of possible checkouts is set to 3. Then, checkout information including the set number of possible checkouts is generated (step S704).
[0285]
On the other hand, if it is determined in step S701 that the watermark is not detected and there is no usage rule, the license management module 511 sets the moving copy flag in the access restriction information ACm to be prohibited from moving copying (= 0), and the number of playbacks is unlimited. (= 255), the security level is set to 1. The reproduction time limit ACp makes the reproduction indefinite (step S705). Thereafter, the license management module 511 generates checkout information including the number of possible checkouts whose initial value is 3 (step S706).
[0286]
After step S704 or S706, the license management module 511 generates a license key Kc by using a random number (step S707), and generates a local use transaction ID and content ID (step S708). Next, the license management module 511 performs a binding key acquisition process. A series of processing from Step S709 in FIG. 23 to Step 723 in FIG. 24 is a binding key acquisition process, which is the same as the series of processing from Step S270 in FIG. 20 to Step S284 in FIG. Therefore, explanation is omitted.
[0287]
Referring to FIG. 24, the license management module 511 that has acquired the binding key Kb acquires the encrypted confidential file 160 from the HDD 530 via the bus BS2, and decrypts the acquired encrypted confidential file 160 with the binding key Kb. A plaintext confidential file is acquired (step S724). Then, the license management module 511 generates content data Dc by encoding the music data acquired from the music CD in a predetermined method (step S725), encrypts the content data with the license key Kc, and encrypts the encrypted content data {Dc } Kc is generated (step S726). Thereafter, the license management module 511 generates content data additional information Dc-inf based on the information from the user input via the keyboard 560 and the information from the music CD (step S727), and the encrypted content. Data {Dc} Kc and additional information Dc-inf are recorded in HDD 530 as content files via bus BS2 (step S728).
[0288]
Then, the license management module 511 uses the generated license (transaction ID, content ID, license key Kc, access restriction information ACm, and reproduction time limit ACp) and the checkout information generated in step S704 or step S706 as confidential information n. Is added to the plaintext confidential file (step S729). Thereafter, the license management module 511 encrypts the plaintext confidential file with the binding key Kb, and updates the encrypted confidential file 160 recorded in the HDD 530 with the encrypted encrypted confidential file 160 (step S730). After storing the license in the encrypted confidential file 160, the license management module 511 includes a content file (encrypted) including the confidential information number n of the confidential information n stored in the encrypted confidential file 160 and the plaintext transaction ID and content ID. The license management file for the encrypted content data {Dc} Kc and the additional information Dc-inf) is generated and recorded in the HDD 530 via the bus BS2 (step S731). Further, the license management module 511 relates to the content information received in the content list file recorded in the HDD 530, the name of the recorded content file and the license management file, and the encrypted content data extracted from the additional information Dc-inf. Information (song name, artist name) and the like are added (step S732), and the entire process is completed (step S733).
[0289]
As described above, the encrypted content data and the license can be acquired also by ripping from the music CD. The encrypted content data and license acquired by ripping from the music CD are managed by the license management module 511 in the same manner as the encrypted content data and level 1 license acquired by distribution.
[0290]
With reference to FIG. 25, management of encrypted content data and licenses received by the license management module 511 or license management device 520 of the personal computer 50 will be described. The HDD 530 of the personal computer 50 includes a content list file 150, the content list file 150 includes content files 1531 to 153n, license management files 1521 to 152n, and encrypted confidential files.
[0291]
The content list file 150 is a data file in the form of a list of owned contents, and includes information (music name, artist name, etc.) for each content, information (file name) indicating the content file and the license management file, and the like. ing. Information on individual contents is described automatically when necessary information is acquired from the additional information Dc-inf at the time of reception or according to a user instruction. In addition, it is possible to manage contents that cannot be reproduced by only content files and only license management files in the list.
[0292]
The content files 1531 to 153n are files for recording the encrypted content data {Dc} Kc and the additional information Dc-inf received by the license management module 511 or the license management device 520, and are provided for each content.
[0293]
The license management files 1521 to 152n are recorded in correspondence with the content files 1531 to 153n, respectively, and are files for managing licenses received by the license management module 511 or the license management device 520. Information for specifying the storage location of the license and information on the license.
[0294]
The information for specifying the storage location is an entry number when a license is recorded in the license management device 520, or a confidential information number for specifying confidential information recorded in the encrypted confidential file.
[0295]
Information related to the license is a transaction ID, content ID that can be referred to in plain text when the license is received, and access restriction information ACm and reproduction control information ACp that can be easily determined from the license purchase condition AC. A copy of plaintext. As is apparent from the above description, the license is protected and recorded so that it cannot be referenced for content protection. However, as long as other information except the license key Kc cannot be rewritten, there is no problem from the standpoint of content protection even if the contents are referred to. In the application program, each process is started with reference to the information on the license.
[0296]
The encrypted confidential information file includes confidential information including licenses managed by the license management module 511 and checkout information. The encrypted confidential information file is encrypted with the binding key Kb.
[0297]
A specific description will be given with reference to FIG. The license management files 1521 and 1524 include entry numbers 1 and m, respectively. This is received by the license management device 520 and designates the management area of the license (license ID, license key Kc, access restriction information ACm, and reproduction time limit ACm) managed in the license area 5215B of the memory 5215 of the license management device 520. Number.
[0298]
Therefore, when moving the encrypted content data with the file name recorded in the content file 1531 to the memory card 110 attached to the playback terminal 100, if the content file 1531 to 153n is searched and the content file 1531 is extracted, the encryption is performed. Where the license for reproducing the encrypted content data is managed. Since the entry number included in the license management file 1521 corresponding to the content file 1531 is “1”, the license for reproducing the encrypted content data with the file name recorded in the content file 1531 is the memory 5215 of the license management device 520. Are recorded in the area designated by the entry number 1 in the license area 5215B. Then, the entry number 1 is read from the license management file 1521 of the content list file 150 recorded in the HDD 530, and the read entry number 1 is input to the license management device 520, whereby the license can be easily obtained from the license area 5215B of the memory 5215. To the memory card 110. After the license is moved, the license in the entry number 1 designated in the license area 5215B of the memory 5215 is deleted, so that “no license” is recorded correspondingly as in the license management file 1523. .
[0299]
Further, the confidential information for storing the license of the encrypted content data received by the license management module 511 is managed by the license management files 1522, 1524,. The license management files 1522,..., 152n include confidential information numbers of confidential information for storing licenses for reproducing the encrypted content data received by the license management module 511.
[0300]
Then, for example, when moving the encrypted content data of the file name recorded in the content file 1532 to the personal computer 80, the content file 1532 is searched by extracting the content file 1531 and the license corresponding to the content file 1532 The confidential information number 1 is acquired from the management file 1522. Meanwhile, the binding key Kb is acquired from the license management device 520, and the encrypted confidential file 160 is decrypted with the acquired binding key Kb to acquire a plaintext confidential file. Then, the license stored in the confidential information 1 in the confidential file corresponding to the confidential information number 1 acquired from the license management file can be acquired.
[0301]
As described above, in the first embodiment of the present invention, the license of the encrypted content data received by the license management module 511 is stored as the confidential information n in the encrypted confidential file 160, and the encrypted confidential file 160 is The license management device 520 can decrypt only the binding key Kb held in hardware. That is, the binding key Kb is a common key for managing the license of the encrypted content data, and has a structure in which a license cannot be acquired without the binding key Kb. Accordingly, since the license of the encrypted content data received by the license management module 511 is written in the encrypted confidential file 160 and recorded in the HDD 530, the license management device 520 is actually managed in software. Since the license cannot be extracted from the encrypted confidential file 160 without the binding key Kb stored in the file, it is practically close to being managed by hardware.
[0302]
On the other hand, the license received by the license management device 520 is stored in the license area 5215B of the memory 5215. Therefore, according to the first embodiment of the present invention, the management level of the license received by the license management module 511 can be brought close to the management level of the license received by the license management device 520.
[0303]
Note that the binding license is stored in the entry number “0”.
[0304]
[Move 1]
In the data distribution system shown in FIG. 1, an operation for transmitting the encrypted content data and license distributed from the distribution server 10 to the license management device 520 of the personal computer 50 to the memory card 110 attached to the playback terminal 100 will be described. This operation is referred to as “movement 1”. Movement is a process performed only between security levels 2
26 to 29 show a moving operation in which the license management device 520 moves the encrypted content data and license received from the distribution server 10 to the memory card 110 attached to the playback terminal 100 in the data distribution system shown in FIG. It is the 1st-4th flowchart for explaining.
[0305]
Prior to the processing in FIG. 18, the user of the personal computer 50 determines the content to be moved according to the content list file, can specify the content file and license management file in the HDD 530, and obtains the play list file in the memory card 110. The explanation is based on the assumption that
[0306]
Referring to FIG. 26, when a movement request is input from keyboard 560 of personal computer 50 (step S300), controller 510 sends authentication data transmission request a via USB interface 550, terminal 580, and USB cable 70. Is transmitted to the playback terminal 100 (step S302). Then, the controller 1106 of the playback terminal 100 receives the authentication data transmission request via the terminal 1114, the USB interface 1112 and the bus BS3, and sends the authentication data transmission request via the bus BS3 and the memory card interface 1200 to the memory card 110. Send to. Then, the controller 1420 of the memory card 110 receives the authentication data transmission request via the terminal 1426, the interface 1424, and the bus BS4 (step S304).
[0307]
Upon receiving the authentication data transmission request, controller 1420 reads authentication data {KPm3 // Cm3} KPa2 from authentication data holding unit 1400 via bus BS4, and reads the read authentication data {KPm3 // Cm3} KPa2 on the bus. The data is output to the playback terminal 100 via the BS 4, the interface 1424 and the terminal 1426. Then, the controller 1106 of the playback terminal 100 receives the authentication data {KPm3 // Cm3} KPa2 via the memory card interface 1200 and the bus BS3, and the personal computer via the bus BS3, the USB interface 1112, the terminal 1114, and the USB cable 70. Authentication data {KPm3 // Cm3} KPa2 is transmitted to 50 (step S306).
[0308]
Then, controller 510 of personal computer 50 receives authentication data {KPm3 // Cm3} KPa2 via terminal 580 and USB interface 550 (step S308), and buses the received authentication data {KPm3 // Cm3} KPa2. The data is transmitted to the license management device 520 via BS2. The controller 5220 of the license management device 520 receives the authentication data {KPm3 // Cm3} KPa2 via the terminal 5226, the interface 5224, and the bus BS5, and decrypts the received authentication data {KPm3 // Cm3} KPa2. 5208. The authentication processing unit 5208 receives the authentication data authentication data {KPm3 // Cm3} KPa2 and the KPa holding unit 5214 receives the level 2 authentication key KPa2 from the KPa holding unit 5214 based on the authentication data {KPm3 // Cm3} KPa2. And the decryption process of the authentication data {KPm3 // Cm3} KPa2 is executed with the received level 2 authentication key KPa2 (step S310). Based on the result of the decryption process in the decryption processing unit 5208, the controller 5220 determines whether or not the process has been performed normally, that is, the memory card 110 holds the class public encryption key KPm3 and the class certificate Cm3 from the legitimate memory card. In order to authenticate this, authentication processing is performed to determine whether or not authentication data subjected to encryption for proving its validity has been received by a legitimate organization (step S312). If it is determined that the authentication data is valid, the controller 5220 approves and accepts the class public encryption key KPm3 and the class certificate Cm3. Then, the process proceeds to the next process (step S314). If it is not valid authentication data, it is rejected and the process is terminated without accepting the class public encryption key KPm3 and the class certificate Cm3 (step S404).
[0309]
If it is recognized that the memory card is a legitimate memory card as a result of the authentication, the controller 5220 next determines whether or not the class certificate Cm3 of the memory card 110 is listed in the prohibited class list CRL. When the class certificate is inquired to 5215A and these class certificates are the subject of the prohibited class list, the moving operation is ended here (step S404).
[0310]
On the other hand, if the class certificate of the memory card 110 is not included in the prohibited class list, the process proceeds to the next process (step S314).
[0311]
As a result of authentication, if it is confirmed that the access is from a playback terminal including a memory card having valid authentication data and the class is not included in the prohibited class list, the controller 5220 moves the controller 5220 in the license management device 520. Is acquired from the license area 5215B of the memory 5215 (step S316). Session key generation unit 5218 generates session key Ks22 for movement (step S318). Session key Ks22 is encrypted by encryption processing unit 5210 using class public encryption key KPm3 corresponding to memory card 110 obtained by decryption processing unit 5208 (step S320). The controller 5220 acquires the encrypted data {Ks22} Km3 via the bus BS5, adds the transaction ID acquired from the memory 5215 to the encrypted data {Ks22} Km3 // {Ks22} Km3 as the bus BS5, The data is output via the interface 5224 and the terminal 5226 (step S322).
[0312]
Referring to FIG. 27, controller 510 of personal computer 50 receives transaction ID // {Ks22} Km3 via bus BS2 (step S324), via USB interface 550, terminal 580, and USB cable 70. Transaction ID // {Ks22} Km3 is transmitted to playback terminal 100 (step S324). Then, the controller 1106 of the playback terminal 100 receives the transaction ID // {Ks22} Km3 via the terminal 1114, the USB interface 1112, and the BS3, and uses the received transaction ID // {Ks22} Km3 as the memory card interface 1200. To the memory card 110. Then, the controller 1420 of the memory card 110 receives the transaction ID // {Ks22} Km3 via the terminal 1426, the interface 1424, and the bus BS4 (step S326). Decryption processing unit 1422 receives {Ks22} Km3 from controller 1420 via bus BS4, decrypts {Ks22} Km3 with class secret decryption key Km3 from Km holding unit 1421, and accepts session key Ks22 (step S328). ). Then, the session key generation unit 1418 generates a session key Ks2 (step S330), and the controller 1420 acquires the update date / time CRLdate of the prohibited class list from the CRL area 1415A of the memory 1415 via the bus BS4, and acquires the acquired The update date / time CRLdate is given to the changeover switch 1446 (step S332).
[0313]
Then, the encryption processing unit 1406 encrypts the session key Ks2, the individual public encryption key KPmc4, and the update date / time CRLdate acquired by sequentially switching the terminals of the changeover switch 1446 using the session key Ks22 decrypted by the decryption processing unit 1404. , Encrypted data {Ks2 // KPmc4 // CRLdate} Ks22 is generated. The controller 1420 outputs the encrypted data {Ks2 // KPmc4 // CRLdate} Ks22 to the playback terminal 100 via the bus BS4, the interface 1424 and the terminal 1426, and the controller 1106 of the playback terminal 100 passes the memory card interface 1200. The encrypted data {Ks2 // KPmc4 // CRLdate} Ks22 is received. Then, the controller 1106 transmits to the personal computer 50 via the USB interface 1112, the terminal 1114, and the USB cable 70 (step S334).
[0314]
The controller 510 of the personal computer 50 receives the encrypted data {Ks2 // KPmc4 // CRLdate} Ks22 via the terminal 580 and the USB interface 550 (step S336), and receives the encrypted data {Ks2 // via the bus BS2. KPmc4 // CRLdate} Ks22 is input to the license management device 520 (step S338). The controller 5220 of the license management device 520 receives the encrypted data {Ks2 // KPmc4 // CRLdate} Ks22 via the terminal 5226, the interface 5224 and the bus BS5, and receives the received encrypted data {Ks2 // KPmc4 // CRLdate} Ks22 is given to the decoding processing unit 5212. Decryption processing unit 5212 decrypts encrypted data {Ks2 // KPmc4 // CRLdate} Ks22 using session key Ks22 from session key generation unit 5218, and accepts session key Ks2, public encryption key KPmc4, and prohibited class list CRLdate. (Step S340).
[0315]
Then, controller 510 of personal computer 50 reads the license entry number contained in the license management file from HDD 530 in step S324. Then, the controller 510 inputs the read entry number to the license management device 520 via the bus BS2 (step S342). The controller 5220 of the license management device 520 receives the entry number via the terminal 5226, the interface 5224, and the bus BS5, and licenses (transaction ID, content) from the area specified by the received entry number in the license area 5215B of the memory 5215. ID, license key Kc, access restriction information ACm, reproduction time limit ACp) are read (step S344).
[0316]
In response to the reception of the access restriction information ACm, the controller 5220 confirms the access restriction information ACm (step S346). That is, the controller 5220 sequentially determines the security level, the number of times of reproduction, and the movement / duplication flag of the acquired access restriction information ACm. First, based on the security level of the access restriction information ACm and the authentication key used in step S310, when the level 1 authentication key KPa1 is used and the security level of the access restriction information ACm is 2, the license Since the output is a security level lower than the management request level, the process proceeds to step S404, and the movement operation is stopped. Otherwise, the following determination is made. Based on the number of reproductions of the access restriction information ACm, it is determined whether or not the license to move to the memory card 110 attached to the reproduction terminal 100 is a license that does not allow reproduction of the encrypted content data by the access restriction information ACm. Check. When the number of times of reproduction has reached the limit number of times according to the access restriction information ACm (= 0), the encrypted content data cannot be reproduced with the license, and the encrypted content data and the license are attached to the reproduction terminal 100. This is because there is no point in moving to the memory card 110. When the number of reproductions is “0”, the process proceeds to step S404 and the moving operation is stopped. In other cases (the number of reproductions ≠ 0), the following determination is performed. Based on the moving copy flag of the access restriction information ACm, when the moving copy prohibition is “= 0”, the moving operation is stopped in parallel with step S404. When only the transfer is possible, the controller 5220 deletes the license in the entry number designated in the license area 5215B of the memory 5215 (step S348) and the step S350 in parallel. = 2 ”, it is determined that the license is duplicated, and step S348 is not performed, and the process is parallel to step S350.
[0317]
Referring to FIG. 28, the encryption processing unit 5217 encrypts the license with the individual public encryption key KPmc4 unique to the license management device 520 obtained by the decryption processing unit 5212, and generates encrypted data {transaction ID // content ID / / Kc // ACm // ACp} Kmc4 is generated (step S350). Then, the update date / time CRLdate transmitted from the memory card 110 is compared with the update date / time of the prohibited class list held by the license management device 520 in the CRL area 5215A to determine which of the prohibited class lists is new, and the memo card When it is determined that 100 is newer, the process proceeds to step S352. If it is determined that the license management device 520 is newer, the process proceeds to step S362 (step S352).
[0318]
When it is determined that the data CRLdate is the latest, the encryption processing unit 5206 uses the encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc4 output from the encryption processing unit 5217 as the session key. Encryption is performed by the session key Ks2 generated in the generation unit 5218, and the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 is output to the bus BS5. Then, the controller 5220 transmits the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 on the bus BS5 to the personal computer 50 via the interface 5224 and the terminal 5226 ( Step S354).
[0319]
The controller 510 of the personal computer 50 receives the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 and reproduces it via the USB interface 550, the terminal 580, and the USB cable 70. It transmits to the terminal 100 (step S356).
[0320]
The controller 1106 of the playback terminal 100 receives the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 via the terminal 1114, the USB interface 1112, and the bus BS3. The received encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 is transmitted to the memory card 110 via the bus BS3 and the memory card interface 1200. Then, the controller 1420 of the memory card 110 receives the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 via the terminal 1426, the terminal 1424, and the bus BS4 ( Step S358).
[0321]
Decryption processing unit 1412 of memory card 110 receives encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 via bus BS4 and is generated by session key generation unit 1418. The session key Ks2 is decrypted and {transaction ID // content ID // Kc // ACm // ACp} Kmc4 is accepted (step S360). Thereafter, the process proceeds to step S376 shown in FIG.
[0322]
On the other hand, if it is determined in step S350 that the license management device 520 is newer, the controller 5220 of the license management device 520 acquires the latest prohibited class list CRL from the CRL area 5215A of the memory 5215 via the bus BS5. (Step S362).
[0323]
The encryption processing unit 5206 receives the output of the encryption processing unit 5217 and the data CRL of the prohibited class list acquired by the controller 5220 from the memory 5215 via the bus BS5 via the changeover switches 5242 and 5246, respectively. Encryption is performed using the session key Ks 2 generated by the session key generation unit 5218. The encrypted data output from the encryption processing unit 5206 {CRL // {transaction ID // content ID / interface 5224, and output to the personal computer 50 via the terminal 5226 (step S364).
[0324]
The controller 510 of the personal computer 50 receives the output encrypted data {CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2, receives the USB interface 550, the terminal 580, and The encrypted data {CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 is transmitted to the playback terminal 100 via the USB cable 70 (step S368). The controller 1106 of the playback terminal 100 receives the encrypted data {CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 via the terminal 1114, the USB interface 1112, and the bus BS3. The encrypted data {CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 is transmitted to the memory card 110 via the bus BS3 and the memory card interface 1200. The controller 1420 of the memory card 110 receives the encrypted data {CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc4} Ks2 via the terminal 1426, the interface 1424, and the bus BS4. Receive (step S370).
[0325]
In the memory card 110, the decryption processing unit 1412 decrypts the received data on the bus BS4 using the session key Ks2 given from the session key generation unit 1418, and CRL and {transaction ID // content ID // Kc // ACm // ACp} Kmc4 is received (step 372). The controller 1420 receives the data CRL received by the decoding processing unit 1412 via the bus BS4, and rewrites the CRL area 1415A of the memory 1415 with the received data CRL (step S374).
[0326]
In steps S354, S356, S358, and S360, when the prohibited class list CRL of the memory card 110 on the transmitting side is newer than the prohibited class list CRL of the license management device 520 on the receiving side, the license key Kc and the like are transferred to the memory card 110. Steps S362, S364, S368, S370, S372, and S374 are licenses when the prohibited class list CRL of the license management device 520 on the transmission side is newer than the prohibited class list CRL of the memory card 110 on the reception side. This is a movement operation of the key Kc or the like to the memory card 110. As described above, the updated date / time CRLdate of the prohibited class list sent from the memory card 110 is checked one by one, and the latest prohibited class list CRL is stored in the CRL area 1514A as the prohibited class list CRL of the memory card 110. Therefore, it is possible to prevent the license from being leaked to a device whose security function is broken such as leakage of the class secret key.
[0327]
Referring to FIG. 29, after step S360 or step S374, the encryption license {transaction ID // content ID // Kc // ACm // ACp} Kmc4 is received by the decryption processing unit 1404 according to an instruction from the controller 1420. Decrypted by the individual secret decryption key Kmc4 and the license (license key Kc, transaction ID, content ID, access restriction information ACm, and reproduction time limit ACp) is received (step S376).
[0328]
In this way, by exchanging the encryption keys generated respectively by the license management device and the memory card, performing encryption using the encryption keys received by each other, and transmitting the encrypted data to the other party, Even in the transmission / reception of encrypted data, virtual mutual authentication can be performed, and security in the operation of moving the encrypted content data and the license can be improved.
[0329]
The controller 510 of the personal computer 50 transmits the entry number for storing the license transferred to the memory card 110 to the playback terminal 100 via the USB interface 550, the terminal 580, and the USB cable 70 (step S378). Then, the controller 1106 of the playback terminal 100 receives the entry number via the terminal 1114, the USB interface 1112, and the bus BS3, and transmits the entry number to the memory card 110 via the bus BS3 and the memory card interface 1200. 1420 receives the entry number via the terminal 1426 and the interface 1424, and stores the license (license key Kc, transaction ID, content ID, contents ID, and license ID) acquired in step S376 in the license area 1415B of the memory 1415 specified by the received entry number. The access restriction information ACm and the reproduction time limit ACp) are stored (step S380).
[0330]
The controller 510 of the personal computer 50 includes the license entry number stored in the memory 1415 of the memory card 110 and the encrypted content data {Dc} Kc to be transferred to the memory card 110 including the plaintext transaction ID and content ID. A license management file for the additional information Dc-inf is generated and transmitted to the memory card 110 (step S382).
[0331]
The controller 1420 of the memory card 110 receives the license management file via the playback terminal 100, and records the received license management file in the data area 1415C of the memory 1415 (step S384).
[0332]
Then, the controller 510 of the personal computer 50 proceeds to step S388 if it is a movement according to the determination in step S346, and does not perform step S388 if it is a copy, but performs step S390 in parallel (step S386). In the case of transfer, the license entry number of the license management file for the license transferred to the memory card 110 among the licenses recorded in the HDD 530 is updated to “no license” (step S386).
[0333]
Thereafter, the controller 510 acquires the content file (encrypted content data {Dc} Kc and additional information Dc-inf) to be transferred to the memory card 110 from the HDD 530, and stores {Dc} Kc // Dc-inf in the memory. The data is transmitted to the card 110 (step S390). The controller 1420 of the memory card 110 receives {Dc} Kc // Dc-inf via the playback terminal 100 (step S392), and receives the {Dc} Kc // Dc-inf received via the bus BS4 as a content file. Is recorded in the data area 1415C of the memory 1415 (step S394).
[0334]
Then, the controller 510 of the personal computer 50 creates a playlist file in which the music moved to the memory card 110 is added (step S396), and transmits the playlist file and a rewrite instruction of the playlist file to the memory card 110. (Step S398). The controller 1420 of the memory card 110 receives the playlist file and the rewrite instruction via the playback terminal 100 (step S400), and receives the playlist file recorded in the data area 1415C of the memory 1415 via the bus BS4. The replay list file is rewritten (step S402), and the moving operation ends (step S404).
[0335]
The reproduction list file is a management information file for a reproduction terminal created for the same purpose as the content list file recorded in the HDD. The playback terminal 100 performs playback by specifying the content file and the license management file in the order of appearance of the content included in the playlist file.
[0336]
In this way, after confirming that the memory card 110 attached to the playback terminal 100 is a legitimate device, the public encryption key KPm3 encrypted and transmitted together with the class certificate Cm3 is valid. The content data can be moved only in response to a move request to a memory card that is not described in the class certificate Cm3 is prohibited class list, that is, the class certificate list whose encryption with the public encryption key KPm3 is broken. Therefore, it is possible to prohibit movement to an unauthorized memory card and movement using a decrypted class key. Further, by using this moving operation, the user of the playback terminal 102 that does not have a communication function with the distribution server 10 can also receive the encrypted content data and the license on the memory card via the personal computer 50. User convenience is improved.
[0337]
Further, as is apparent from the description, the transfer process has been described. However, when the license copy is permitted by the content supplier, the process is executed as a copy process, and the license is held as it is in the license management device 511 on the transmission side. Is done. Copying in this case is permitted only when the content supplier, that is, the copyright owner, permits copying at the time of distribution, and the mobile copy flag of the access restriction information ACm is set to allow mobile copying. This is not an act that hinders the rights of the copyright owner. Access restriction information is part of the license, and its confidentiality is guaranteed, but the copyright is protected.
[0338]
In the above description, the transfer of the license from the license management device 520 of the personal computer 50 to the memory card 110 has been described. However, the transfer of the license from the memory card 110 to the license management device 520 is also illustrated in FIGS. This is done according to the flowchart. In addition, the encrypted content data and license received from the distribution server 10 by the personal computer 50 can be transferred to the memory card 110, so that only the encrypted content data and license received by the license management device 520 from the distribution server 10 in hardware. In addition, the encrypted content data and license received by the license management module 511 from the distribution server 10 in software cannot be transmitted to the memory card based on the concept of “move”. The license management module 511 exchanges authentication data and an encryption key with the distribution server 10 in a software manner with a security level lower than that of the license management device 520, and receives encrypted content data and a license. The possibility that the encryption is broken in the operation is higher than when the encrypted content data and the license are received by the license management device 520. Accordingly, the encrypted content data and license received and managed with a low security level are “moved” to the memory card 110 that receives and manages the encrypted content data and license with the same security level as the license management device 520. Since the security level in the memory card 110 is lowered, the encrypted content data received by the license management module 511 and the license received by the license management module 511 are stored in the memory by the concept of “move”. The transmission to the card 110 is disabled.
[0339]
However, if the encrypted content data and the license with a low security level received by the license management module 511 cannot be transferred to the memory card 110 at all, a free copy of the content data is permitted while protecting the copyright. Contrary to the purpose of the data distribution system, user convenience is not improved. Therefore, the encrypted content data and license received by the license management module 511 can be transmitted to the memory card 110 by the concept of check-out and check-in described below.
[0340]
[check out]
In the data distribution system shown in FIG. 1, an operation of transmitting the encrypted content data and license distributed from the distribution server 10 to the license management module 511 of the personal computer 50 to the memory card 110 attached to the playback terminal 100 will be described. This operation is called “checkout”.
[0341]
30 to 34 show, in the data distribution system shown in FIG. 1, the encrypted content data and license received by the license management module 511 from the distribution server 10 to the memory card 110 attached to the playback terminal 100 on condition of return. It is the 1st-5th flowchart for demonstrating the check-out operation which borrows. Before the processing in FIG. 30, the user of the personal computer 50 determines the content to be checked out according to the content list file, can specify the content file and the license management file in the HDD 530, and obtains the play list file in the memory card 110. The explanation is based on the assumption that
[0342]
Referring to FIG. 30, when a checkout request is input from keyboard 560 of personal computer 50 (step S500), license management module 511 performs a binding key acquisition process. A series of processing from step S501 in FIG. 30 to step 515 in FIG. 31 is a binding key acquisition process, which is the same as the series of processing from step S270 in FIG. 20 to step S284 in FIG. Therefore, explanation is omitted.
[0343]
The license management module 511 that has acquired the binding key Kb acquires the encrypted confidential file 160 from the HDD 530 via the bus BS2, and acquires the plaintext confidential file by decrypting the acquired encrypted confidential file 160 with the binding key Kb. (Step S516). Thereafter, the license management module 511 sends the confidential information n (transaction ID, content ID, license key Kc, access restriction information ACm, reproduction time limit ACp, and confidential information in the confidential file corresponding to the confidential information number n recorded in the license management file. Checkout information) is acquired (step S517).
[0344]
Then, the license management module 511 confirms whether or not the license can be checked out based on the acquired access restriction information ACm (step S518). That is, the license management module 511 confirms that the memory card attached to the playback terminal 100 It is checked whether the license to be checked out to 110 has a restriction on the number of times of reproduction of the encrypted content data depending on the number of times of reproduction of the access restriction information ACm, or whether the license is unreproducible. If there is a limit on the number of playbacks, the encrypted content data and license are not checked out.
[0345]
If reproduction is restricted in step S518, the process proceeds to step S564, and the checkout operation ends. In step S518, when the number of reproductions of the encrypted content data has not reached the limit number based on the access restriction information ACm, the process proceeds to step S519. Then, the license management module 511 confirms whether or not the number of possible checkouts included in the acquired checkout information is greater than “0” (step S519). If the possible number of checkouts is “0” in step S519, there is no license that can be checked out, so the process proceeds to step S564, and the checkout operation ends. In step S519, when the possible number of checkouts is greater than “0”, the license management module 511 transmits an authentication data transmission request via the USB interface 550, the terminal 580, and the USB cable 70 (step S520). The controller 1106 of the playback terminal 100 receives an authentication data transmission request via the terminal 1114, the USB interface 1112, and the bus BS3, and stores the received authentication data transmission request in the memory via the bus BS3 and the memory card interface 1200. Send to card 110. Then, the controller 1420 of the memory card 110 receives the authentication data transmission request via the terminal 1426, the interface 1424, and the bus BS4 (step S521).
[0346]
Upon receiving the authentication data transmission request, controller 1420 reads authentication data {KPm3 // Cm3} KPa2 from authentication data holding unit 1400 via bus BS4, and reads the read authentication data {KPm3 // Cm3} KPa2 on the bus. The data is output to the playback terminal 100 via the BS 4, the interface 1424 and the terminal 1426. Then, the controller 1106 of the playback terminal 100 receives the authentication data {KPm3 // Cm3} KPa2 via the memory card interface 1200 and the bus BS3, and the personal computer via the bus BS3, the USB interface 1112, the terminal 1114, and the USB cable 70. Authentication data {KPm3 // Cm3} KPa2 is transmitted to 50 (step S522).
[0347]
Then, the license management module 511 of the personal computer 50 receives the authentication data {KPm3 // Cm3} KPa2 via the terminal 580 and the USB interface 550 (step S523), and the received authentication data {KPm3 // Cm3} KPa2 Is decrypted with the level 2 authentication key KPa2 (step S524).
[0348]
Referring to FIG. 32, license management module 511 determines from the decryption processing result whether or not the processing has been performed normally, that is, memory card 110 has class public encryption key KPm3 and class certificate Cm3 from the regular memory card. In order to authenticate that it is held, authentication processing is performed to determine whether or not authentication data subjected to encryption for proving its validity has been received by a legitimate organization (step S525). If it is determined that the authentication data is valid, the license management module 511 approves and accepts the class public encryption key KPm3 and the class certificate Cm3. Then, the process proceeds to the next process (step S526). If it is not valid authentication data, it is rejected, and the process is terminated without accepting the class public encryption key KPm3 and the class certificate Cm3 (step S564).
[0349]
When it is recognized that the memory card is a legitimate memory card as a result of the authentication, the license management module 511 next inquires the HDD 530 whether the class certificate Cm3 of the memory card 110 is listed in the prohibited class list CRL. If these class certificates are included in the prohibited class list, the check-out operation ends here (step S564). On the other hand, if the class certificate of the memory card 110 is not included in the prohibited class list, the process proceeds to the next process (step S526).
[0350]
As a result of authentication, when it is confirmed that the access is from a playback terminal including a memory card having valid authentication data and the class is not included in the prohibited class list, the license management module 511 identifies the checkout. Therefore, a checkout transaction ID, which is a management code, takes a value different from all the transaction IDs stored in the memory card 110 and is generated as a transaction ID for local use. Generate (step S527). Then, the license management module 511 generates a session key Ks2b for checkout (step S528), and encrypts the generated session key Ks2b with the class public encryption key KPm3 transmitted from the memory card 110 (step S529). ). Then, the license management module 511 sends the checkout transaction ID // {Ks2b} Km3 obtained by adding the checkout transaction ID to the encrypted data {Ks2b} Km3 via the USB interface 550, the terminal 580, and the USB cable 70. It transmits to the reproduction terminal 100 (step S530). Then, the controller 1106 of the playback terminal 100 receives the checkout transaction ID // {Ks2b} Km3 via the terminal 1114, the USB interface 1112, and the bus BS3, and the received checkout transaction ID // {Ks2b } Km3 is transmitted to the memory card 110 via the memory card interface 1200. Then, the controller 1420 of the memory card 110 receives the checkout transaction ID // {Ks2b} Km3 via the terminal 1426, the interface 1424, and the bus BS4 (step S531). Decryption processing unit 1422 receives {Ks2b} Km3 from controller 1420 via bus BS4, decrypts {Ks2b} Km3 with secret decryption key Km3 from Km holding unit 1421, and accepts session key Ks2b (step S532). . Then, the session key generation unit 1418 generates a session key Ks2c (step S533), and the controller 1420 acquires the update date / time CRLdate of the prohibited class list from the CRL area 1415A of the memory 1415 via the bus BS4, and acquires the acquired The update date / time CRLdate is given to the changeover switch 1446 (step S534).
[0351]
Then, the encryption processing unit 1406 encrypts the session key Ks2c, the individual public encryption key KPmc4, and the update date / time CRLdate acquired by sequentially switching the terminals of the changeover switch 1446 using the session key Ks2b decrypted by the decryption processing unit 1404. , Encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b is generated. The controller 1420 outputs the encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b to the playback terminal 100 via the bus BS4, the interface 1424 and the terminal 1426, and the controller 1106 of the playback terminal 100 passes through the memory card interface 1200. Encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b. Then, the controller 1106 transmits to the personal computer 50 via the USB interface 1112, the terminal 1114, and the USB cable 70 (step S535).
[0352]
The license management module 511 of the personal computer 50 receives the encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b via the terminal 580 and the USB interface 550 (step S536), and the received encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b is decrypted with the session key Ks2b, and the session key Ks2c, the individual public encryption key KPmc4, and the update date / time CRLdate are received (step S537). Then, the license management module 511 generates checkout access restriction information ACm that prohibits the license from being transferred / replicated from the memory card mounted on the playback terminal 100 to another memory card or the like. In other words, the access restriction information ACm is generated in which the number of reproductions is unlimited (= 255), the moving duplication flag is not movable duplication (= 3), and the security level is set to 1 (step S538).
[0353]
Referring to FIG. 33, the license management module 511 encrypts the license with the public encryption key KPmc4 unique to the memory card 110 received in step S537 and encrypts the data {checkout transaction ID // content ID // Kc. // Checkout ACm // ACp} Kmc4 is generated (step S539). Then, the update date / time CRLdate transmitted from the memory card 110 is compared with the update date / time of the prohibited class list held in the HDD 530 managed by the license management module 511 to determine which of the prohibited class lists is newer. When it is determined that 110 is newer, the process proceeds to step S541. Conversely, when it is determined that the license management module 511 is newer, the process proceeds to step S544 (step S540).
[0354]
When it is determined that the memory card 110 is newer, the license management module 511 uses the encrypted data {checkout transaction ID // content ID // Kc // checkout ACm // ACp} Kmc4 as the session key Ks2c. The encrypted data {{transaction ID for checkout // content ID // Kc // ACm // ACp for checkout} Kmc4} Ks2c is transmitted via the USB interface 550, the terminal 580, and the USB cable 70. Is transmitted to the playback terminal 100 (step S541).
[0355]
The controller 1106 of the playback terminal 100 transmits the encrypted data {{transaction ID for checkout // content ID // Kc // ACm // ACp for checkout} Kmc4} via the terminal 1114, the USB interface 1112, and the bus BS3. Ks2c is received, and the received encrypted data {{transaction ID for checkout // content ID // Kc // ACm for checkout / ACp} Kmc4} is stored in memory via bus BS3 and memory card interface 1200. Send to card 110. Then, the controller 1420 of the memory card 110 transmits the encrypted data {{transaction ID for checkout // content ID // Kc // ACm // ACp for checkout} Kmc4 via the terminal 1426, the terminal 1424, and the bus BS4. } Ks2c is received (step S542).
[0356]
The decryption processing unit 1412 of the memory card 110 receives the encrypted data {{checkout transaction ID // content ID // Kc // checkout ACm // ACp} Kmc4} Ks2c via the bus BS4, and receives the session key. Decryption is performed using the session key Ks2c generated by the generation unit 1418, and {checkout transaction ID // content ID // Kc // checkout ACm // ACp} Kmc4 is accepted (step S543). Thereafter, the process proceeds to step S549 shown in FIG.
[0357]
On the other hand, if it is determined in step S540 that the prohibited class list of the license management module 511 is newer, the license management module 511 acquires the prohibited class list CRL managed by the license management module 511 from the HDD 530 (step S544).
[0358]
Then, the license management module 511 receives {checkout transaction ID // content ID // Kc // checkout ACm // ACp} Kmc4 and the data CRL of the prohibited class list acquired from the HDD 530 using the session key Ks2c. The encrypted data {CRL // {checkout transaction ID // content ID // Kc // checkout ACm // ACp} Kmc4} Ks2c is transmitted via the USB interface 550, the terminal 580 and the USB cable 70. Is transmitted to the playback terminal 100 (step S545). The controller 1106 of the playback terminal 100 transmits encrypted data {CRL // {checkout transaction ID // content ID // Kc // checkout ACm // ACp via the terminal 1114, the USB interface 1112 and the bus BS3. } Kmc4} Ks2c is received, and the received encrypted data {CRL // {checkout transaction ID // content ID // Kc // checkout ACm // ACp} Kmc4} Ks2c is transferred to the bus BS3 and the memory card. The data is output to the memory card 110 via the interface 1200. Then, the controller 1420 of the memory card 110 transmits the encrypted data {CRL // {checkout transaction ID // content ID // Kc // checkout ACm // via the terminal 1426, the interface 1424, and the bus BS4. ACp} Kmc4} Ks2c is received (step S546).
[0359]
In the memory card 110, the decryption processing unit 1412 decrypts the received data on the bus BS4 using the session key Ks2c given from the session key generating unit 1418, and CRL and {checkout transaction ID // content ID // Kc // ACm for checkout / ACp} Kmc4 is received (step 547). The controller 1420 receives the data CRL accepted by the decryption processing unit 1412 via the bus BS4, and rewrites the CRL area 1415A of the memory 1415 with the received data CRL (step S548).
[0360]
Steps S541, S542, and S543 are operations for checking out the license key Kc and the like to the memory card 110 when the prohibited class list CRL of the memory card 110 on the receiving side is newer than the prohibited class list CRL of the license management module 511 on the transmitting side. Steps S 544, S 545, S 546, S 547, and S 548 are memory such as a license key Kc when the prohibited class list CRL of the license management module 511 on the transmission side is newer than the prohibited class list CRL of the memory card 110 on the reception side. This is a checkout operation to the card 110. As described above, when a license is transmitted to the memory card 110, if a new prohibited class list CRL is recorded in the HDD 530 from the prohibited class list CRL held by the memory card 100 in the CRL area 1415B, the prohibited class list CRL is stored. Is obtained from the HDD 530, and the prohibited class list CRL is distributed to the memory card 110, whereby the prohibited class list that the memory card 100 holds in the CRL area 1415B can be updated. 110 can be prohibited from being transmitted to the tie line, and the outflow of the distributed license can be prevented.
[0361]
Referring to FIG. 34, after step S543 or step S548, the encryption license {checkout transaction ID // content ID // Kc // checkout ACm // ACp} Kmc4 is determined by an instruction from the controller 1420. In the decryption processing unit 1404, decryption is performed using the secret decryption key Kmc4, and the license (license key Kc, checkout transaction ID, content ID, checkout ACm, and reproduction time limit ACp) is received (step S549).
[0362]
Then, the license management module 511 of the personal computer 50 transmits an entry number for storing the license checked out to the memory card 110 to the playback terminal 102 via the USB interface 550, the terminal 580, and the USB cable 70. (Step S550). Then, the controller 1106 of the playback terminal 102 receives the entry number via the terminal 1114, the USB interface 1112, and the bus BS3, and accepts it in the license area 1415B of the memory 1415 specified by the received entry number in step S566. The license (license key Kc, checkout transaction ID, content ID, checkout ACm, and playback control information ACp) is stored (step S551).
[0363]
The license management module 511 of the personal computer 50 encrypts content data to be transferred to the memory card 110 including the license entry number stored in the memory 1415 of the memory card 110, the plaintext checkout transaction ID, and the content ID. A license management file for {Dc} Kc and additional information Dc-inf is generated and transmitted to the memory card 110 (step S552).
[0364]
The controller 1420 of the memory card 110 receives the license management file via the playback terminal 102, and records the received license management file in the data area 1415C of the memory 1415 (step S553).
[0365]
The license management module 511 of the personal computer 50 updates the checkout information by subtracting 1 from the number of possible checkouts and adding the checkout transaction ID and the public encryption key KPmc4 unique to the checkout destination memory card ( Step S554). Then, the license management module 511 sends the transaction ID, content ID, license key Kc, access restriction information ACm, reproduction time limit ACp, and updated address information (number of checkouts possible, checkout transaction ID, checkout destination) The plaintext secret file is updated with the new secret information n (the individual door-to-door public encryption key KPmc4 added to the memory card 110) (step S555). The individual public key KPmc4 of the checkout destination is stored in the memory card without a tamper-resistant module and has a unique value for each memory card obtained by a highly secure communication means using encryption by authentication. Suitable as identification information for identifying memory cards.
[0366]
Thereafter, the license management module 511 encrypts the plaintext confidential file with the binding key Kb and updates the encrypted confidential file 160 recorded in the HDD 530 (step S556).
[0367]
The license management module 511 acquires the encrypted content data {Dc} Kc and additional information Dc-inf to be checked out to the memory card 110 from the HDD 530, and sends {Dc} Kc // Dc-inf to the memory card 110. Transmit (step S557). The controller 1420 of the memory card 110 receives {Dc} Kc // Dc-inf via the playback terminal 100 (step S558), and receives the {Dc} Kc // Dc-inf received via the bus BS4 in the memory 1415. Is recorded in the data area 1415C (step S559).
[0368]
Then, the license management module 511 of the personal computer 50 creates a playlist file in which the music that has been checked out to the memory card 110 is added (step S560), and sends the playlist file and an instruction to rewrite the playlist file to the memory card. 110 (step S561). The controller 1420 of the memory card 110 receives the playlist and the rewrite instruction via the playback terminal 100 (step S562), and receives the playlist file recorded in the data area 1415C of the memory 1415 via the bus BS4. The reproduction list file is rewritten (step S563), and the checkout operation ends (step S564).
[0369]
In this way, it is confirmed that the memory card 110 attached to the playback terminal 100 is a legitimate device, and at the same time, the class public encryption key KPm3 encrypted and transmitted together with the class certificate Cm3 is valid. The class certificate Cm3 is checked out only for a checkout request to a memory card that is not listed in the prohibited class list, that is, the class certificate list whose encryption with the class public encryption key KPm3 is broken. It is possible to prohibit check-out to an unauthorized memory card and check-out using a decrypted class key. In addition, the encryption keys generated by the license management module and the memory card are exchanged, encryption is performed using the encryption keys received by each other, and the encrypted data is transmitted to the other party. Even when encrypted data is transmitted / received, virtual mutual authentication can be performed, and security in the checkout operation of the encrypted content data and the license can be improved. Further, by using this check-out operation, the user of the playback terminal 100 who does not have a communication function with the distribution server 10 also receives the encrypted content data and license received by the personal computer 50 by software in the memory card. The convenience of the user can be improved.
[0370]
[check-in]
An operation of returning the encrypted content data and license checked out from the license management module 511 of the personal computer 50 to the memory card 110 in the data distribution system shown in FIG. 1 to the license management module 511 will be described. This operation is called “check-in”.
[0371]
FIGS. 35 to 38 show a first check-in operation for returning encrypted content data and licenses lent to the memory card 110 by the check-out operation described with reference to FIGS. FIG. 4 is a fourth flowchart. Prior to the processing in FIG. 35, the user of the personal computer 50 obtains the content list file recorded in the HDD 520 and the playlist file recorded in the data area 1415B of the memory card 110, and checks according to both files. Description will be made on the assumption that content to be loaded is determined, content files and license management files of the HDD 530 and the memo card 110 can be specified, and the license management file of the memory card 110 has been acquired.
[0372]
Referring to FIG. 35, when a check-in request is input from keyboard 560 of personal computer 50 (step S600), license management module 511 performs a binding key acquisition process. A series of processes from step S601 in FIG. 35 to step 615 in FIG. 36 is a binding key acquisition process, which is the same as the series of processes from step S270 in FIG. 20 to step S284 in FIG. Therefore, explanation is omitted.
[0373]
The license management module 511 that has acquired the binding key Kb acquires the encrypted confidential file 160 from the HDD 530 via the bus BS2, and acquires the plaintext confidential file by decrypting the acquired encrypted confidential file 160 with the binding key Kb. (Step S616). Thereafter, the license management module 511 reads the confidential information n (license (transaction ID, content ID, license key Kc, access restriction information ACm, reproduction time limit ACp) in the confidential file corresponding to the confidential information number n recorded in the license management file. ) And check-out information (number of check-outs, check-out transaction ID, individual public encryption key KPmcx of the check-out destination memory card)) is acquired (step S617). Then, the license management module 511 transmits an authentication data transmission request to the playback terminal 100 via the USB interface 550, the terminal 580, and the USB cable 70 (step S618).
[0374]
Then, the controller 1106 of the playback terminal 100 receives the authentication data transmission request via the terminal 1114, the USB interface 1112 and the bus BS3, and sends the authentication data transmission request via the bus BS3 and the memory card interface 1200 to the memory card 110. Send to. Then, the controller 1420 of the memory card 110 receives the authentication data transmission request via the terminal 1426, the interface 1424, and the bus BS4 (step S619).
[0375]
Upon receiving the authentication data transmission request, controller 1420 reads authentication data {KPm3 // Cm3} KPa2 from authentication data holding unit 1400 via bus BS4, and reads the read authentication data {KPm3 // Cm3} KPa2 on the bus. The data is output to the playback terminal 100 via the BS 4, the interface 1424 and the terminal 1426. Then, the controller 1106 of the playback terminal 100 receives the authentication data {KPm3 // Cm3} KPa2 via the memory card interface 1200 and the bus BS3, and the personal computer via the bus BS3, the USB interface 1112, the terminal 1114, and the USB cable 70. Authentication data {KPm3 // Cm3} KPa2 is transmitted to 50 (step S620).
[0376]
The license management module 511 of the personal computer 50 receives the authentication data {KPm3 // Cm3} KPa2 via the terminal 580 and the USB interface 550 (step S621), and levels the received authentication data {KPm3 // Cm3} KPa2 2. Decrypt using the authentication key KPa (step S622). Then, the license management module 511 determines from the decryption processing result whether or not the processing has been normally performed, that is, the memory card 110 holds the class public encryption key KPm3 and the class certificate Cm3 from the legitimate memory card. In order to authenticate, authentication processing is performed to determine whether or not authentication data subjected to encryption for proving its validity has been received by a legitimate institution (step S623). If it is determined that the authentication data is valid, the license management module 511 approves and accepts the class public encryption key KPm3 and the class certificate Cm3. Then, the process proceeds to the next process (step S624). If it is not valid authentication data, it is rejected and the process is terminated without accepting the class public encryption key KPm3 and the class certificate Cm3 (step S653). As a result of the authentication, if the memory card is recognized as a legitimate memory card, the license management module 511 generates a dummy transaction ID (step S624). The dummy transaction ID always takes a value different from all the transaction IDs stored in the memory card 110 and is generated as a transaction ID for local use.
[0377]
Referring to FIG. 37, the license management module 511 generates a check-in session key Ks2b (step S625). Then, the license management module 511 encrypts the generated session key Ks2b with the class public encryption key KPm3 received from the memory card 110 to generate the encrypted data {Ks2b} Km3 (step S626), and the encrypted data {Ks2b} Dummy transaction ID // {Ks2b} Km3 obtained by adding a dummy transaction ID to Km3 is transmitted to playback terminal 100 via USB interface 550, terminal 580, and USB cable 70 (step S627). The controller 1106 of the playback terminal 100 receives the dummy transaction ID // {Ks2b} Km3 via the terminal 1114, the USB interface 1112, and the BS3, and uses the received dummy transaction ID // {Ks2b} Km3 as the memory card interface 1200. To the memory card 110. Then, the controller 1420 of the memory card 110 receives the dummy transaction ID // {Ks2b} Km3 via the terminal 1426, the interface 1424, and the bus BS4 (step S628). Decryption processing unit 1422 receives {Ks2b} Km3 from controller 1420 via bus BS4, decrypts {Ks2b} Km3 using class secret decryption key Km3 from Km holding unit 1421, and accepts session key Ks2b (step S629). ). Then, the session key generation unit 1418 generates a session key Ks2c (step S630), and the controller 1420 acquires the update date / time CRLdate of the prohibited class list from the CRL area 1415A of the memory 1415 via the bus BS4, and acquires the acquired The update date / time CRLdate is given to the changeover switch 1446 (step S631).
[0378]
Then, the encryption processing unit 1406 decrypts the session key Ks2c, the individual public encryption key KPmc4, and the update date / time CRLdate acquired by sequentially switching the terminals of the changeover switch 1446 by the decryption processing unit 1422, and the terminal Pa of the changeover switch 1442 Is encrypted using the session key Ks2b obtained via the encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b. The controller 1420 outputs the encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b to the playback terminal 100 via the bus BS4, the interface 1424 and the terminal 1426, and the controller 1106 of the playback terminal 100 passes through the memory card interface 1200. Encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b. Then, the controller 1106 transmits the encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b to the personal computer 50 via the USB interface 1112, the terminal 1114, and the USB cable 70 (step S632).
[0379]
The license management module 511 of the personal computer 50 receives the encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b via the terminal 580 and the USB interface 550 (step S633), and the received encrypted data {Ks2c // KPmc4 // CRLdate} Ks2b is decrypted with the session key Ks2b, and the session key Ks2c, the individual public encryption key KPmc4, and the update date / time CRLdate are received (step S634).
[0380]
Then, the license management module 511 determines whether the received individual public encryption key KPmc4 is included in the checkout information of the confidential information n acquired in step S617, that is, in the checkout transaction ID of the license to be checked out. It is confirmed whether or not it matches with the corresponding individual public encryption key KPmcx stored (step S635).
[0381]
The received individual public encryption key KPmc4 is included in the updated checkout information when the encrypted content data and the license are checked out (see step S551 in FIG. 34). Therefore, by including the individual public encryption key KPmc4 corresponding to the checkout destination such as the encrypted content data in the checkout information, the checkout destination checked out at the time of check-in can be easily specified.
[0382]
In step S635, when the individual public encryption key KPmc4 is not included in the checkout information, the check-in operation ends (step S653). In step S635, if the individual public encryption key KPmc4 is included in the checkout information, the license management module 511 cannot participate in the reproduction of the dummy license, that is, the dummy transaction ID, the dummy content ID in which the corresponding content does not exist, and the reproduction. A dummy license key Kc (represented as a dummy Kc), dummy access restriction information ACm (represented as a dummy ACm) indicating that the mobile copy flag is “move / copy prohibited” and the number of reproductions is “0”, and a dummy reproduction time limit ACp (dummy) Is expressed by the individual public encryption key KPmc4 to generate encrypted data {dummy transaction ID // dummy content ID // Kc // dummy ACm // dummy ACp} Kmc4 (step S636).
[0383]
The license management module 511 encrypts the encrypted data {dummy transaction ID // dummy content ID // dummy Kc // dummy ACm // dummy ACp} Kmc4 with the session key Ks2c, and the encrypted data {{dummy transaction ID // Dummy content ID // dummy Kc // dummy ACm // dummy ACp} Kmc4} Ks2c is generated, and the generated encrypted data {{dummy transaction ID // dummy content ID // Kc // dummy ACm // Dummy ACp} Kmc4} Ks2c is transmitted to playback terminal 100 via USB interface 550, terminal 580, and USB cable 70 (step S637).
[0384]
The controller 1106 of the playback terminal 100 sends encrypted data {{dummy transaction ID // dummy content ID // dummy Kc // dummy ACm // dummy ACp} Kmc4} Ks2c via the terminal 1114, the USB interface 1112 and the bus BS3. Receive. The controller 1106 transfers the received encrypted data {{dummy transaction ID // dummy content ID // dummy Kc // dummy ACm // dummy ACp} Kmc4} Ks2c to the memory card 110 via the bus BS3 and the memory card interface 1200. Send. Then, the controller 1420 of the memory card 110 receives {{dummy transaction ID // dummy content ID // dummy Kc // dummy ACm // dummy ACp} Kmc4} Ks2c via the terminal 1426, the terminal 1424, and the bus BS4. (Step S638).
[0385]
Referring to FIG. 38, decryption processing unit 1412 of memory card 110 receives {{dummy transaction ID // dummy content ID // dummy Kc // dummy ACm // dummy ACp} Kmc4} Ks2c via bus BS4. Then, decryption is performed using the session key Ks2c generated by the session key generation unit 1418, and {dummy transaction ID // dummy content ID // dummy Kc // dummy ACm // dummy ACp} Kmc4 is received (step S639). The decryption processing unit 1404 receives the encrypted data {dummy transaction ID // dummy content ID // dummy Kc // dummy ACm // dummy ACp} Kmc4 from the decryption processing unit 1412 and receives the received encrypted data {dummy Transaction ID // Dummy Content ID // Dummy Kc // Dummy ACm // Dummy ACp} Kmc4 is decrypted with the individual secret decryption key Kmc4 from the Kmc holding unit 1402, and the dummy transaction ID, dummy content ID, dummy Kc, and dummy ACm , And dummy ACp are received (step S640).
[0386]
The license management module 511 of the personal computer 50 acquires the entry number storing the license to be checked out described in the license management file of the memory card 110, and uses the USB as the entry number for storing the dummy license. The data is transmitted to the playback terminal 102 via the interface 550, the terminal 580, and the USB cable 70 (step S641). Then, the controller 1106 of the playback terminal 102 receives the entry number via the terminal 1114, the USB interface 1112, and the bus BS3, and enters the license area 1415B of the memory 1415 specified by the received entry number via the bus BS4. The dummy license (dummy transaction ID, dummy content ID, dummy license key Kc, dummy access restriction information ACm, and dummy reproduction time limit ACp) is recorded (step S642). Thus, the license checked out to the memory card 110 can be erased by recording the dummy transaction ID, the dummy content ID, the dummy license key Kc, the dummy access restriction information ACm, and the dummy reproduction time limit ACp.
[0387]
Thereafter, the license management module 511 of the personal computer 50 increases the number of possible checkouts in the checkout information by 1, deletes the checkout transaction ID and the individual public key KPmc4 of the checkout destination memory card, and performs the checkout. Information is updated (step S643). Then, the license management module 511 updates the plaintext confidential file using the transaction ID, content ID, license key Kc, access restriction information ACm, reproduction time limit ACp, and updated checkout information as new confidential information n (step S644). Thereafter, the license management module 511 encrypts the plaintext confidential file with the binding key Kb and updates the encrypted confidential file 160 recorded in the HDD 530 (step S645).
[0388]
Then, the license management module 511 receives the content file (encrypted content data {Dc} Kc and additional information Dc-inf) corresponding to the checked-in license recorded in the data area 1415C of the memory card 100 and the license management file. A deletion instruction to be deleted is transmitted to the playback terminal 100 via the USB interface 550, the terminal 580, and the USB cable 70 (step S646). The controller 1106 of the playback terminal 100 receives a content file (encrypted content data {Dc} Kc and additional information Dc-inf) and license management file deletion instruction via the terminal 1114, the USB interface 1112, and the bus BS3 ( Step S647). Then, the controller 1106 outputs an instruction to delete (encrypted content data {Dc} Kc and additional information Dc-inf) and the license management file to the memory card 110, and the controller 1420 of the memory card 110 receives the terminal 1426, The interface 1424 and the instruction to delete the encrypted content data {Dc} Kc, the additional information Dc-inf, and the license management file are received via the bus BS4, and the encrypted content data {14 of the memory 1415 is received via the bus BS4. Dc} Kc and additional information Dc-inf) and the license management file are deleted (step S648).
[0389]
The license management module 511 of the personal computer 50 creates a playlist from which the checked-in music is deleted (step S649), and transmits the playlist and the playlist rewrite instruction to the memory card 110 (step S650). The controller 1420 of the memory card 110 receives the reproduction list and the rewrite instruction via the reproduction terminal 100 (step S651), and rewrites the reproduction list of the memory 1415 via the bus BS4 to the received reproduction list (step S652). The check-in operation ends (step S653).
[0390]
In this way, by returning the encrypted content data and the license from the other party that has checked out the encrypted content data and the license, the license is transferred from the license management module with a low security level where the license transfer is prohibited, Encrypted content data that can be played back with a license acquired with a license management module with a low security level on a playback terminal because a license acquired with a license management module with a low security level can be sent to a memory card with a high security level. Can play and enjoy.
[0390]
The license lent to the memory card is specified by the access restriction information ACm so that the checked out license cannot be output from the memory card to other recording devices (memory card, license management device, and license management module). As a result, the licenses that have been lent will not be leaked. By checking in <returning> the lent license management module, the right of the lent license is returned to the lent license management module. Therefore, it does not allow the copy to be performed against the intention of the author, and is not a process of lowering the security level, and the copyright is also protected.
[0392]
[Regeneration]
Next, with reference to FIG. 39 and FIG. 40, a description will be given of a playback operation in the playback terminal 100 (also referred to as a content playback device, hereinafter the same) of content data that has been moved to the memory card 110 and checked out. It is assumed that, prior to the processing in FIG. 29, the user of the playback terminal 102 determines content (music) to be played according to the play list file, specifies the content file, and acquires the license management file. To do.
[0393]
Referring to FIG. 39, along with the start of the reproduction operation, a reproduction instruction is input to reproduction terminal 100 from operation terminal 1108 by the user of reproduction terminal 100 (step S1000). Then, the controller 1106 reads the authentication data {KPp1 // Cp1} KPa2 from the authentication data holding unit 1500 via the bus BS3, and sends the authentication data {KPp1 // Cp1} KPa2 to the memory card 110 via the memory card interface 1200. Output (step S1002).
[0394]
Then, the memory card 110 accepts the authentication data {KPp1 // Cp1} KPa2 (step S1004). Then, the decryption processing unit 1408 of the memory card 110 decrypts the received authentication data {KPp1 // Cp1} KPa2 using the level 2 authentication key KPa2 held in the KPa holding unit 1414 (step S1006), and the controller 1420 decrypts it. Authentication processing is performed from the decryption processing result in the processing unit 1408. That is, an authentication process for determining whether or not the authentication data {KPp1 // Cp1} KPa2 is regular authentication data is performed (step S1008). If decryption has failed, the process proceeds to step S1048, and the reproduction operation ends. If the authentication data can be decrypted, the controller 1420 determines whether or not the acquired class certificate Cp1 is included in the prohibited class list CRL read from the CRL area 1415A of the memory 1415 (step S1010). In this case, an identification number is given to the class certificate Cp1, and the controller 1420 determines whether or not the received identification number of the class certificate Cp1 exists in the prohibited class list CRL. If it is determined that the class certificate Cp1 is included in the prohibited class list data, the process proceeds to step S1048, and the reproduction operation ends.
[0395]
If it is determined in step S1010 that the class certificate Cp1 is not included in the prohibited class list data CRL, the session key generation unit 1418 of the memory card 110 generates a session key Ks2 for a reproduction session (step S1012). . Then, encryption processing unit 1410 outputs {Ks2} Kp1 obtained by encrypting session key Ks2 from session key generation unit 1418 using class public encryption key KPp1 decrypted by decryption processing unit 1408 to bus BS3 (step S1014). ). Then, controller 1420 outputs {Ks2} Kp1 to memory card interface 1200 via interface 1424 and terminal 1426 (step S1016). The controller 1106 of the playback terminal 100 acquires {Ks2} Kp1 via the memory card interface 1200. Then, the Kp1 holding unit 1502 outputs the secret decryption key Kp1 to the decryption processing unit 1504.
[0396]
Decryption processing unit 1504 decrypts {Ks2} Kp1 using secret decryption key Kp1 paired with public encryption key KPp1 output from Kp1 holding unit 1502, and outputs session key Ks2 to encryption processing unit 1506 ( Step S1018). Then, session key generation unit 1508 generates session key Ks3 for the reproduction session, and outputs session key Ks3 to encryption processing unit 1506 (step S1020). The encryption processing unit 1506 encrypts the session key Ks3 from the session key generation unit 1508 with the session key Ks2 from the decryption processing unit 1504 and outputs {Ks3} Ks2, and the controller 1106 displays the bus BS3 and the memory card interface 1200. And {Ks3} Ks2 is output to the memory card 110 (step S1022).
[0397]
Then, the decryption processing unit 1412 of the memory card 110 inputs {Ks3} Ks2 via the terminal 1426, the interface 1424, and the bus BS4 (step S1024).
[0398]
Referring to FIG. 40, decryption processing unit 1412 decrypts {Ks3} Ks2 using session key Ks2 generated by session key generation unit 1418, and accepts session key Ks3 generated by playback terminal 100 (step). S1026).
[0399]
The controller 1106 of the playback terminal acquires the entry number in which the license is stored from the license management file of the playback request song acquired in advance from the memory card 110, and acquires the entry number acquired in the memory card 110 via the memory card interface 1200. Is output (step S1027).
[0400]
In response to the entry number input, the controller 1420 confirms the access restriction information ACm (step S1028). In step S1028, the access restriction information ACm, which is information related to restrictions on access to the memory, is confirmed by confirming the number of times of reproduction. Specifically, the reproduction operation is performed if reproduction is not possible. When the number of reproductions of the access restriction information is limited, the number of reproductions of the access restriction information ACm is updated (decremented by 1), and the process proceeds to the next step (step S1030). On the other hand, when the number of reproductions is not limited by the number of reproductions of the access restriction information ACm, step S1030 is skipped, and the process proceeds to the next step (step S1032) without updating the access restriction information ACm. .
[0401]
If it is determined in step S1028 that playback is possible in the playback operation, the license key Kc and playback time limit ACp of the playback request song recorded in the license area 1415B of the memory 1415 are output on the bus BS4. (Step S1032).
[0402]
The obtained license key Kc and reproduction time limit ACp are sent to the encryption processing unit 1406 via the contact point Pf of the changeover switch 1446. The encryption processing unit 1406 encrypts the license key Kc received via the changeover switch 1446 and the reproduction time limit ACp using the session key Ks3 received from the decryption processing unit 1412 via the contact Pb of the changeover switch 1442, and {Kc / / ACp} Ks3 is output to bus BS4 (step S1034).
[0403]
The encrypted data output to the bus BS4 is transmitted to the playback terminal 100 via the interface 1424, the terminal 1426, and the memory card interface 1200.
[0404]
In the reproduction terminal 100, the encrypted data {Kc // ACp} Ks3 transmitted to the bus BS3 via the memory card interface 1200 is decrypted by the decryption processing unit 1510, and the license key Kc and the reproduction time limit ACp are received. (Step S1036). Decryption processing unit 1510 transmits license key Kc to decryption processing unit 1516 and outputs reproduction time limit ACp to bus BS3.
[0405]
The controller 1106 receives the reproduction time limit ACp via the bus BS3 and confirms whether reproduction is possible (step S1040).
[0406]
In step S1040, when it is determined that the reproduction is impossible due to the reproduction time limit ACp, the reproduction operation is terminated.
[0407]
If it is determined in step S1040 that playback is possible, the controller 1106 requests encrypted content data {Dc} Kc recorded as a content file in the data area 1415C of the memory card 110 via the memory card interface 1200. Then, the controller 1420 of the memory card 110 acquires the encrypted content data {Dc} Kc from the memory 1415 and outputs it to the memory card interface 1200 via the bus BS4, the interface 1424, and the terminal 1426 (step S1042).
[0408]
The controller 1106 of the playback terminal 100 acquires the encrypted content data {Dc} Kc via the memory card interface 1200, and provides the encrypted content data {Dc} Kc to the decryption processing unit 1516 via the bus BS3.
[0409]
Then, the decryption processing unit 1516 decrypts the encrypted content data {Dc} Kc with the content key Kc output from the decryption processing unit 1510, and acquires content data Data (step S1044).
[0410]
The decrypted content data Dc is output to the music playback unit 1518, the music playback unit 1518 plays back the content data, and the DA converter 1519 converts the digital signal into an analog signal and outputs it to the terminal 1530. Then, the music data is output from the terminal 1530 to the headphones 130 via the external output device and reproduced (step S1046). This completes the reproduction operation.
[0411]
In the above description, the encrypted content data recorded in the memory card 110 is played back by the playback terminal 100. However, the license management is performed by incorporating the content playback device 1550 shown in FIG. The encrypted content data received by the module 511 and the license management device 520 can be reproduced. When the encrypted content data acquired by the license management module 511 is played back by the content playback device 1550, the license management module 511 acquires the binding key Kb stored in the license management device 520 and recorded in the HDD 530. The encrypted confidential file 160 is decrypted with the binding key Kb, the license is read from the plaintext confidential file, and provided to the content reproduction device 1550.
[0412]
In addition, by incorporating a playback unit that functions in accordance with software for playing back encrypted content data in the personal computers 50 and 80, the encrypted content data acquired by the license management module 511 can be played back by software. . Also in this case, the license management module 511 acquires the binding key Kb stored in the license management device 520, decrypts the encrypted confidential file 160 recorded in the HDD 530 with the binding key Kb, and obtains the license from the plaintext confidential file. It is read out and given to the content reproduction device 1550. Compared to playback with hardware confidentiality (level 2) using the content playback device 1550, playback by software is playback with software confidentiality (level 1), and thus processing with a low security level. is there. Therefore, the license held in the license management device 520 cannot be used for reproduction by this software.
[0413]
[Move 2]
An operation of moving the encrypted content data and license acquired by the license management module 511 of the personal computer 50 to the personal computer 80 in the data distribution system shown in FIG. This movement is referred to as [movement 2].
[0414]
FIGS. 41 to 48 are first to eighth flowcharts for explaining the transfer of the encrypted content data and license acquired by the license management module 511 to the personal computer 80. Before the processing in FIG. 41, it is assumed that the user of the personal computer 50 determines the content to be moved according to the content list file and specifies the content file and license management file of the HDD 530 and the memo card 110. To do. The natural number w for identifying the class of the license management module in the receiving personal computer 80 is w = 5, and the natural number y for identifying the license management module is y = 5.
[0415]
Referring to FIG. 41, when a license transfer request acquired by license management module 511 of personal computer 50 is input via keyboard 560 of personal computer 50 (step S800), license management module 511 of personal computer 50 is entered. Performs a binding key acquisition process. A series of processes from step S801 in FIG. 41 to step 815 in FIG. 42 is a binding key acquisition process, which is the same as the series of processes from step S270 in FIG. 20 to step S284 in FIG. Therefore, explanation is omitted.
[0416]
When the binding license is acquired, the license management module 511 of the personal computer 50 acquires the encrypted confidential file 160 from the HDD 530 via the bus BS2, and decrypts the acquired encrypted confidential file 160 with the binding key Kb to obtain a plaintext. A confidential file is acquired (step S816). Thereafter, the license management module 511 of the personal computer 50 performs confidential information n (transaction ID, content ID, license key Kc, access restriction information ACm, reproduction) in the confidential file corresponding to the confidential information number n recorded in the license management file. The time limit ACp and checkout information) are acquired (step S817).
[0417]
Then, the license management module 511 of the personal computer 50 confirms whether or not the encrypted content data can be moved and copied based on the acquired access restriction information ACm (step S518), that is, the license management module 511 Whether or not the license to be transferred to the personal computer 80 is a license that cannot transfer and copy the encrypted content data by the access restriction information ACm based on the number of reproductions of the acquired access restriction information ACm and the movement / duplication flag. Confirm.
[0418]
If it is determined in step S818 that moving and copying of the encrypted content data is prohibited, the process proceeds to step S903, and the moving operation ends. If it is determined in step S818 that moving and copying of the encrypted content data is not prohibited, the process proceeds to step S819. Then, the license management module 511 confirms whether or not checkout is possible based on the acquired checkout information (step S819). If the checkout is impossible in step S819, the checkout is prohibited, so the process proceeds to step S903 and the checkout operation ends. In step S819, if the checkout is possible, the license management device 520 cannot be authenticated in the device confirmation process for performing the device confirmation process to confirm whether a new binding key can be stored in the license management device 520, or If a new binding key cannot be recorded by the prohibited class list CRL, the process is interrupted to maintain the current state. A series of processing from step S821 in FIG. 42 to step 833 in FIG. 43 is device confirmation processing, which is the same as the series of processing from step S16 in FIG. 10 to step S42 in FIG. Therefore, explanation is omitted.
[0419]
When the device confirmation process ends, the license management module 511 of the personal computer 50 transmits an authentication data transmission request to the personal computer 80 via the communication cable 90 (step S834). Then, the license management module of the personal computer 80 receives the authentication data transmission request (step S835).
[0420]
Upon receiving the authentication data transmission request, the license management module of the personal computer 80 transmits the authentication data {KPm5 // Cm5} KPa1 to the personal computer 50 (step S836). The license management module 511 of the personal computer 50 receives the authentication data {KPm5 // Cm5} KPa1 via the terminal 580 and the USB interface 550 (step S837), and levels the received authentication data {KPm5 // Cm5} KPa1. Decryption is performed using one authentication key KPa1 (step S838).
[0421]
Referring to FIG. 44, license management module 511 determines from the decryption processing result whether or not the processing has been normally performed, that is, memory card 110 has class public encryption key KPm5 and class certificate Cm5 from the regular memory card. In order to authenticate that it is held, authentication processing is performed to determine whether or not authentication data subjected to encryption for proving its validity has been received by a legitimate institution (step S839). If it is determined that the authentication data is valid, the license management module 511 approves and accepts the public encryption key KPm3 and the certificate Cm3. Then, the process proceeds to the next process (step S840). If it is not valid authentication data, it is rejected, and the process is terminated without accepting the class public encryption key KPm5 and the class certificate Cm5 (step S903). When it is recognized that the memory card is a legitimate memory card as a result of the authentication, the license management module 511 next inquires the HDD 530 whether the class certificate Cm3 of the memory card 110 is listed in the prohibited class list CRL. If these class certificates are included in the prohibited class list, the moving operation ends here (step S903). On the other hand, if the class certificate of the memory card 110 is not included in the prohibited class list, the process proceeds to the next process (step S840).
[0422]
As a result of authentication, when it is confirmed that the access is from a playback terminal including a memory card having valid authentication data and the class is not included in the prohibited class list, the license management module 511 transfers the session key Ks2d for movement. Is generated (step S841). Then, the license management module 511 encrypts the generated session key Ks2d with the class public encryption key KPm5 received from the personal computer 80, generates encrypted data {Ks2d} Km5 (step S842), and encrypted data {Ks2d} Transaction ID // {Ks2d} Km5 obtained by adding the transaction ID to Km5 is transmitted to personal computer 80 via communication cable 90 (step S843). The license management module of the personal computer 80 receives the transaction ID // {Ks2d} Km5 (step S844). Then, the license management module of the personal computer 80 decrypts {Ks2d} Km5 with the class secret decryption key Km3 and accepts the session key Ks2d (step S845). Then, the license management module of the personal computer 80 generates a session key Ks2e (step S846), and acquires the update date / time CRLdate of the prohibited class list CRL from the HDD (step S847).
[0423]
Then, the license management module of the personal computer 80 encrypts the session key Ks2e, the individual public encryption key KPmc5, and the prohibited class list CRLdate with the session key Ks2d, and generates encrypted data {Ks2e // KPmc5 // CRLdate} Ks2d, The encrypted data {Ks2e // KPmc5 // CRLdate} Ks2d is transmitted to the personal computer 50 via the communication cable 90 (step S848).
[0424]
The license management module 511 of the personal computer 50 receives the encrypted data {Ks2e // KPmc5 // CRLdate} Ks2d via the terminal 580 and the USB interface 550 (step S849), and the received encrypted data {Ks2e // KPmc5 // CRLdate} Ks2d is decrypted with session key Ks2d, and session key Ks2e, individual public encryption key KPmc5, and update date / time CRLdate are received (step S850). Then, the license management module 511 encrypts the transaction ID, the content ID, the license key Kc, the access restriction information ACm, and the reproduction time limit ACp with the individual public encryption key KPmc5 unique to the personal computer 80 and encrypts the data {transaction ID / / Content ID // Kc // ACm // ACp} Kmc5 is generated (step S851).
[0425]
Referring to FIG. 45, the license management module 511 of the personal computer 50 manages the prohibited class managed by the license management module of the personal computer 80 based on the update date / time CRLdate of the prohibited class list transmitted from the license management module of the personal computer 80. It is determined which of the list and the prohibited class list managed by itself is new, and when it is determined that the prohibited class list CRL managed by itself is old, the process proceeds to step S853. Conversely, when it is determined that the prohibited class list CRL managed by itself is newer, the process proceeds to step S856 (step S852).
[0426]
When it is determined that the prohibited class list CRL managed by the license management module 511 is old, the license management module 511 generates encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc5 in the license management module 511. The encrypted session key Ks2e is encrypted, and the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc5} Ks2e is transmitted to the personal computer 80 via the communication cable 90 (step) S853).
[0427]
Then, the license management module of the personal computer 80 receives the encrypted data {{transaction ID // content ID // Kc // ACm // ACp} Kmc5} Ks2e (step S854) and the encrypted data {{transaction ID. // Content ID // Kc // ACm // ACp} Kmc5} Ks2e is decrypted with the session key Ks2e, and {transaction ID // content ID // Kc // ACm // ACp} Kmc5 is received (step S855). . Thereafter, the process proceeds to step S861.
[0428]
On the other hand, if it is determined in step S852 that the prohibited class list CRL managed by itself is new, the license management module 511 of the personal computer 50 acquires the prohibited class list CRL from the HDD 530 (step S856). Then, the license management module 511 receives the prohibited class list CRL and the encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc5 and encrypts the encrypted data with the session key Ks2e { CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc5} Ks2e is transmitted to the personal computer 80 via the communication cable 90 (step S857).
[0429]
The personal computer 80 receives the transmitted encrypted data {CRL // {transaction ID // content ID // Kc // ACm // ACp} Kmc5} Ks2e (step S858), and the license management module receives the session key. The received data is decrypted using Ks2e and accepted as CRL and encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc5 (step S859).
[0430]
The license management module of the personal computer 80 rewrites the prohibited class list CRL recorded in the HDD with the received CRL (step S860).
[0431]
In steps S853, S854, and S855, the prohibited class list CRL held by the personal computer 80 on the receiving side is held by the personal computer 50 on the rent side depending on the update date / time CRLdate of the prohibited class list sent from the personal computer 80. When the prohibited class list CRL is newer, the license key Kc is moved to the personal computer 80. Steps S854, S855, S856, S857, and S860 are prohibited class lists held by the personal computer 80 on the receiving side. This is a movement operation of the license key Kc and the like to the personal computer 80 when the prohibited class list CRL held by the personal computer 50 on the transmission side is older.
[0432]
After step S855 or step S860, the license management module of the personal computer 80 decrypts the encrypted data {transaction ID // content ID // Kc // ACm // ACp} Kmc5 using the individual secret decryption key Kmc5 and the license. (License key Kc, transaction ID, content ID, access restriction information ACm, and reproduction time limit ACp) are accepted (step S861). Then, the license management module determines whether or not the number of reproductions is restricted by the received access restriction information ACm. If the number of reproductions is not restricted, the license management module proceeds to step S863, and if the number of reproductions is restricted, step S863. The process proceeds to S864 (step S862). When the number of reproductions is not limited, the license management module generates checkout information including the number of checkouts for renting the encrypted content and license received from the personal computer 50 to another device (step). S863). In this case, the initial value of checkout is set to “3”. When the number of times of reproduction is limited, the license management module sets the number of checkouts available for renting the encrypted content data to another device to “0” and generates checkout information (step S864). ). Thereafter, the process proceeds to step S880 in FIG.
[0433]
After step S853 or step S857, the rewriting operation of the binding license held by the personal computer 50 is performed in parallel with the personal computer 50 moving the license to the personal computer 80. After step S853 or step S857, the license management module 511 of the personal computer 50 determines whether or not the license can be duplicated based on the access restriction information ACm (step 865). If the license can be copied, the process proceeds to step S898 in FIG. 48, and the encrypted content data {Dc} Kc and the additional information Dc-inf are transmitted to the personal computer 80. In step S865, when only the migration is permitted by the migration decoding flag of the license access restriction information ACm, the license management module 511 reads the license management file 152n of the content list file 150 related to the migrated license recorded in the HDD 530, The secret information number n recorded in the management file is changed to no license and the license management file 152n is updated (step S866), and a new binding key Kbb different from the first generated binding key Kb is generated (step S867). ). Then, the license management module 511 deletes the confidential information n in the plaintext confidential file, encrypts the confidential file with the newly generated binding key Kbb, and updates the encrypted confidential file 160 in the HDD 530 (step S868). .
[0434]
Referring to FIG. 46, license management module 511 performs binding key registration processing from step S869 to step S879 in order to store newly generated binding key Kbb in license management device 520. This is the same processing as the series of processing from step S44 in FIG. 11 to step S66 in FIG. 12 in the initialization flowchart, and only the binding key Kb is changed to the new binding key Kbb and the session key Ks2b is changed to the session key Ks2c. It is. Therefore, explanation is omitted.
[0435]
When the registration of the new binding key Kbb is completed, the process proceeds to step S898 in FIG.
[0436]
Referring to FIG. 47, after step S861 or step S862 in FIG. 45, in personal computer 80, the binding key Kb2 is acquired from the built-in license management module, that is, the binding key is acquired. The personal computer 80 is the same as the personal computer 50, and a series of processes from step S878 to step S893 in FIG. 48 is a binding key acquisition process, and step S270 in FIG. 20 to step S284 in FIG. To the acquired binding license (transaction IDb2, content IDb2, binding key Kb2, and control information ACmb2, ACpb2), and the session keys Ks2a and Ks2b are changed to Ks2g and Ks2f, respectively. Only. Therefore, explanation is omitted.
[0437]
When the binding key Kb2 is acquired, the license management module of the personal computer 80 acquires the encrypted confidential file 160 from the HDD 530 via the bus BS2, and decrypts the acquired encrypted confidential file 160 with the binding key Kb2 to obtain a plaintext. A confidential file is acquired (step S895). Thereafter, the license management module converts the license (transaction ID, content ID, license key Kc, access restriction information ACm, reproduction time limit ACp) and checkout information received from the personal computer 50 into a plain text confidential file as new confidential information n2. An additional entry is made (step S896). Then, the license management module encrypts the plaintext confidential file with the binding key Kb2 and updates the encrypted confidential file 160 recorded in the HDD (step S897).
[0438]
Then, when both step S868 and step S897 in FIG. 45 are completed, the license management module 511 of the personal computer 50 stores the content file (encrypted content data {Dc} Kc and additional information Dc-inf) recorded in the HDD 530. The read and encrypted content data {Dc} Kc and additional information Dc-inf are transmitted to the personal computer 80 via the communication cable 90 (step S898).
[0439]
The license management module of the personal computer 80 receives the encrypted content data {Dc} Kc and the additional information Dc-inf, and accepts the encrypted content data {Dc} Kc and the additional information Dc-inf (step S899). . Then, the license management module records the received encrypted content data {Dc} Kc and additional information Dc-inf on the HDD via the bus BS2 as a content file (step S900). Also, the license management module creates a license management file for the content file in which the encrypted content data {Dc} Kc and the additional information Dc-inf including the confidential information number n2, the transaction ID, and the content ID are recorded and stored in the HDD. Recording is performed (step S901). Then, the license management module appends the name of the received content to the content file of the content list file recorded in the HDD (step S902), and the movement operation ends (step S903).
[0440]
As described above, by managing the license of the encrypted content data acquired by the license management module 511 of the personal computer 50 using the binding key Kb, the encrypted content data and the license can be transferred from the personal computer 50 to the personal computer 80. it can.
[0441]
According to the first embodiment, the license management module built in the personal computer manages the license of the encrypted content data acquired by the software using the binding key managed in hardware by the license management device. The encrypted content data and the license can be transmitted to another personal computer by the concept of “move” in the same way as the license of the encrypted content data acquired by.
[0442]
[Embodiment 2]
With reference to FIG. 49, the management method in Embodiment 2 of the license of the encrypted content data acquired by the license management module 511 will be described.
[0443]
The configuration of the content list file 150 is the same as that in the first embodiment. The HDD 530 stores an encrypted confidential file 160, which stores the same transaction IDb, content IDb, and binding key Kb stored in the license management device 520. The encrypted confidential file 160 is uniquely encrypted so that it cannot be taken out from the personal computer 50 depending on the serial number of the CPU of the personal computer 50. Of the license management files 1522,..., 152n, the license management files 1522 and 152n correspond to the license management files corresponding to the licenses acquired by the license management module 511. It includes encrypted confidential information obtained by encrypting confidential information including license and checkout information in the same manner as the encrypted confidential file, and plain text information regarding the license. The binding license is always stored in the entry number “0” of the license management device 520 to be stored.
[0444]
In addition, the license management file corresponding to the license stored in the license management device, the license management files 1521 and 152n correspond to the encrypted confidential information, and the entry number that identifies the entry to be licensed in the license area 1415B of the license management device. Is recorded. The configuration of the other files and license area 1415B is the same as that in FIG.
[0445]
When the license is taken out from the license management file 1522,..., 152n, if the license management file 1522... 152n contains encrypted confidential information, the entry number “0” is transmitted to the license management device 520 and the license is obtained. The binding key Kb is acquired from the management device 520, and it is confirmed that the acquired binding key Kb matches the binding key Kb stored in the encrypted confidential file 160. If they match, the encrypted confidential information is decrypted to obtain the license and checkout information. If they do not match, the license acquisition is prohibited and the processing is stopped. On the other hand, if the entry number is included, the processing is left to the license management device 520. Furthermore, if there is no license, the license does not exist and the processing is stopped. Therefore, in the second embodiment, the binding key Kb stored in the license management device 520 and the binding key Kb stored in the encrypted confidential file 160 are all processed for a license with a low security level (level 1). If they do not match, the license management file 1522,..., 152n is operated so that the license of the encrypted content data cannot be taken out.
[0446]
As a result, also in the second embodiment, the license of the encrypted content data acquired by the license management module 511 can be managed by the binding key Kb, and the personal data is the same as described in the first embodiment. The encrypted content data and license can be transferred from the computer 50 to the personal computer 80.
[0447]
[Initialization]
50 to 52 are first to third flowcharts for explaining initialization of the encrypted confidential file 160 according to the second embodiment. The flowcharts shown in FIGS. 50 to 52 are the same as the flowcharts of FIGS. 10 to 12 except that step S66 of the flowcharts shown in FIGS. 10 to 12 is replaced with step S66a. Therefore, referring to FIG. 52, after step S64, license management module 511 stores transaction IDb, content IDb, and binding key Kb in a plaintext confidential file and performs original encryption on the plaintext confidential file. The encrypted confidential file 160 is created, and the created encrypted confidential file 160 is recorded in the HDD 530 (step S66a). Then, the initialization operation ends (step S68).
[0448]
[Distribution 2]
53 to 56 are first to fourth flowcharts for explaining operations when receiving encrypted content data and a license from the distribution server 10 from the license management module 511 in the second embodiment. The flowchart shown in FIGS. 53 to 56 is obtained by replacing the steps between steps S266, S268 and S288 in the flowcharts shown in FIGS. 17 to 21 with steps S287a to S287a. This is the same as the flowchart shown in FIG. Referring to FIG. 56, after checkout information is generated in steps S266 and S268, license management module 511 receives accepted licenses (transaction ID, content ID, license key Kc, access restriction information ACm, and reproduction time limit ACp). ), Checkout information, and binding information are uniquely encrypted to generate encrypted confidential information (step S286a). Then, the license management module 511 creates a license management file including the generated encrypted confidential information, transaction ID, and content ID, and records it in the HDD 530 (step S287a). Thereafter, the process proceeds to step S288, where the above-described steps are executed, and the encrypted content data and license distribution operation ends.
[0449]
[Ripping]
FIGS. 57 and 58 are first and second flowcharts for explaining the ripping operation in which license management module 511 obtains encrypted content data and a license from a music CD in the second embodiment. The flowcharts shown in FIGS. 57 and 58 are obtained by replacing the steps between steps S708 and S725 in the flowcharts shown in FIGS. 22 to 24 with steps S720a to S724a. To the flowchart shown in FIG. Referring to FIG. 58, after step S708, the license management module 511 converts the received license (transaction ID, content ID, license key Kc, access restriction information ACm, and reproduction time limit ACp), checkout information, and binding information. Encrypted confidential information is generated by performing unique encryption (step S723a). Then, the license management module 511 creates a license management file including the generated encrypted confidential information, transaction ID, and content ID, and records it in the HDD 530 (step S724a). Thereafter, the process proceeds to step S725, where the above-described steps are executed, and the operation of ripping the encrypted content data and license ends.
[0450]
[check out]
59 to 63 illustrate first to first operations for checking out the encrypted content data and license acquired by the license management module 511 to the memory card 110 attached to the playback terminal 100 in the second embodiment. It is a 5th flowchart. The flowcharts shown in FIGS. 59 to 63 are obtained by replacing steps S516 and S517 in the flowcharts shown in FIGS. 30 to 34 with steps S516a, S516b, and S517a and replacing steps S552 and S553 with steps S552a and 553a. Except for this, it is the same as the flowchart shown in FIGS. Referring to FIG. 60, after step S515, the license management module 511 acquires the encrypted confidential file 160 recorded in the HDD 530, and acquires the binding key Kb that is decrypted and stored (step S516a). . Then, the license management module 511 determines whether the binding key Kb acquired from the license management device 520 matches the binding key Kb acquired from the encrypted confidential file 160, and the two binding keys Kb do not match each other. When the process proceeds to step S564, the checkout operation ends. When the two binding keys Kb match each other, the process proceeds to the next step S517a (step S516b).
[0451]
When the binding key Kb acquired from the license management device 520 matches the binding key Kb acquired from the encrypted confidential file 160, the encrypted confidential information is acquired from the license license management file and decrypted (license key Kc, transaction ID, content ID, access restriction information ACm, and reproduction count ACp) are obtained (step 517a). Then, the process proceeds to next step S5118.
Referring to FIG. 63, after step S551, the license management module 511 generates encrypted confidential information by performing original encryption on the confidential information reflecting the updated checkout information (step S552a). The license management file including the confidential information is updated (step S553a). Thereafter, the process proceeds to step S554, where the above-described steps are executed, and the encrypted content data and license check-out operation ends.
[0452]
As described above, the license management module acquires the license of the encrypted content data from the license management file only when the binding key stored in the license management device 520 matches the binding key stored in the encrypted confidential file 160. . Therefore, also in the second embodiment, the license of the encrypted content data is substantially managed by the binding key.
[0453]
[check-in]
FIGS. 64 to 67 show a first operation for checking in the encrypted content data and license checked out by the license management module 511 to the memory card 110 attached to the playback terminal 100 in the second embodiment. FIG. 4 is a fourth flowchart. The flowcharts shown in FIGS. 64 to 67 are obtained by replacing steps S616 and S617 in the flowcharts shown in FIGS. 35 to 38 with steps S616a, 616b, and 617a and replacing steps S643 and S644 with steps S643a and 644a. Except for this, it is the same as the flowchart shown in FIGS.
[0454]
Referring to FIG. 65, after step S615, the license management module 511 acquires the encrypted confidential file 160 recorded in the HDD 530, acquires the binding key Kb stored by decryption (step S616a). . Then, the license management module 511 determines whether the binding key Kb acquired from the license management device 520 matches the binding key Kb acquired from the encrypted confidential file 160, and the two binding keys Kb do not match each other. When the process proceeds to step S653, the check-in operation ends. When the two binding keys Kb match each other, the process proceeds to the next step S618 (step S616b).
[0455]
When the binding key Kb acquired from the license management device 520 matches the binding key Kb acquired from the encrypted confidential file 160, the encrypted confidential information is acquired from the license management file and decrypted (license key Kc, transaction ID). , Content ID, access restriction information ACm, and reproduction count ACp) are obtained (step 617a). Then, the process proceeds to next step S5118.
[0456]
Referring to FIG. 67, after step S642, the license management module 511 generates encrypted confidential information by performing original encryption on the confidential information reflecting the updated checkout information (step S644a). The license management file including the classified information is updated (step S645a). Thereafter, the process proceeds to step S646, where the above-described steps are executed, and the encrypted content data and license check-in operation ends.
[0457]
[Move 2]
68 to 74 are first to seventh flowcharts for explaining the operation of moving the encrypted content data and license received by the license management module 511 from the personal computer 50 to the personal computer 80 in the second embodiment. It is. 68 to 74, steps S800a to S800c are inserted between step S800 and step S801 of the flowcharts shown in FIGS. 39 to 46, and steps between step S815 and step S820 are set to step S816a. , 817a, step S867 is replaced with step S867a and step S867b, and steps between steps S862, S863, and step S897 are replaced with steps S895a to 896a. Otherwise, FIGS. It is the same as the flowchart shown.
[0458]
Referring to FIG. 68, after step S800, license management module 511 decrypts the encrypted confidential information in the license management file and decrypts the confidential information (transaction ID, content ID, license key Kc, access). The restriction information ACm, the reproduction time limit ACp, and the checkout information are acquired (step S800a), and the license management module 511 determines whether the encrypted content data and the license can be transferred and copied based on the ACm acquired in step S800a. When the transfer and copying of the encrypted content data and license are prohibited, the license management module 511 moves to step S903 to end the transfer operation, and the transfer and copy are prohibited. The process proceeds to step S800c when they are not (step S800b).
[0459]
When the encrypted content data and the b license can be transferred and copied, the license management module 511 determines whether or not the checkout is possible based on the checkout information. If not, the license management module 511 proceeds to step S903. The moving operation ends, and when the checkout is possible, the process proceeds to step S801.
[0460]
Referring to FIG. 69, after step S815, license management module 511 obtains encrypted confidential file 160 recorded in HDD 530, and obtains binding key Kb decrypted and stored (step S816a). . Then, the license management module 511 determines whether the binding key Kb acquired from the license management device 520 matches the binding key Kb acquired from the encrypted confidential file 160, and the two binding keys Kb do not match each other. In step S903, the movement operation ends. When the two binding keys Kb match each other, the process proceeds to the next step S820 (step S817a).
[0461]
Referring to FIG. 72, after step S867, license management module 511 rewrites binding key Kb stored in the plain secret file to binding key Kbb (step S868a), and performs encryption with its own encryption. The encrypted confidential file is generated and rewritten with the encrypted confidential file in the HDD 530 (step S868b). Next, the process proceeds to step S869 in FIG.
[0462]
Referring to FIG. 74, after check-out information is generated in steps S862 and S863, license management module 511 accepts the received license (transaction ID, content ID, license key Kc, access restriction information ACm, and reproduction time limit ACp). The encrypted confidential information is generated by applying original encryption to the checkout information (step S895a). Then, the license management module 511 creates a license management file including the generated encrypted confidential information, transaction ID, and content ID, and records it in the HDD 530 (step S896a). Thereafter, the process proceeds to step S897, where the above-described steps are executed, and the encrypted content data and license distribution operation ends.
[0463]
Other parts are the same as those in the first embodiment.
According to the second embodiment, the license management module built in the personal computer manages the license of the encrypted content data acquired by the software using the binding key managed in hardware by the license management device. The encrypted content data and the license can be transmitted to another personal computer by the concept of “move” in the same way as the license of the encrypted content data acquired by.
[0464]
In the first and second embodiments, the license management device 520 can store a binding license and a license by distribution. However, the license management device 520 may be a management device dedicated to a binding license.
[0465]
Further, although an entry number is specified to specify a binding license, it may have a dedicated entry and be distinguished from a high level license.
[0466]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.
[Brief description of the drawings]
FIG. 1 is a schematic diagram conceptually illustrating a data distribution system according to Embodiment 1 of the present invention.
2 is a diagram showing characteristics of data, information, etc. for communication in the data distribution system shown in FIG.
3 is a diagram showing characteristics of data, information, etc. for communication in the data distribution system shown in FIG.
4 is a diagram showing characteristics of data, information, etc. for communication in the data distribution system shown in FIG.
FIG. 5 is a schematic block diagram illustrating a configuration of a distribution server in the data distribution system illustrated in FIG. 1;
6 is a schematic block diagram showing a configuration of a personal computer in the data distribution system shown in FIG.
7 is a schematic block diagram showing a configuration of a playback terminal in the data distribution system shown in FIG.
8 is a schematic block diagram showing a configuration of a memory card in the data distribution system shown in FIG.
9 is a schematic block diagram showing the configuration of a license management device built in the personal computer shown in FIG.
10 is a first flowchart for explaining initialization of a confidential file in the personal computer shown in FIG. 1; FIG.
11 is a second flowchart for explaining initialization of a confidential file in the personal computer shown in FIG. 1; FIG.
FIG. 12 is a third flowchart for explaining initialization of a confidential file in the personal computer shown in FIG. 1;
FIG. 13 is a first flowchart for explaining a distribution operation with a high security level in the data distribution system shown in FIG. 1;
14 is a second flowchart for explaining a distribution operation with a high security level in the data distribution system shown in FIG. 1; FIG.
FIG. 15 is a third flowchart for explaining a distribution operation with a high security level in the data distribution system shown in FIG. 1;
FIG. 16 is a fourth flowchart for explaining a distribution operation with a high security level in the data distribution system shown in FIG. 1;
17 is a first flowchart for explaining a distribution operation with a low security level in the data distribution system shown in FIG. 1; FIG.
FIG. 18 is a second flowchart for explaining a distribution operation with a low security level in the data distribution system shown in FIG. 1;
FIG. 19 is a third flowchart for explaining a distribution operation with a low security level in the data distribution system shown in FIG. 1;
20 is a fourth flowchart for explaining a distribution operation with a low security level in the data distribution system shown in FIG. 1; FIG.
FIG. 21 is a fifth flowchart for explaining a distribution operation with a low security level in the data distribution system shown in FIG. 1;
FIG. 22 is a first flowchart for explaining a ripping operation in the data distribution system shown in FIG. 1;
FIG. 23 is a second flowchart for explaining the ripping operation in the data distribution system shown in FIG. 1;
24 is a third flowchart for explaining the ripping operation in the data distribution system shown in FIG. 1; FIG.
FIG. 25 is a diagram showing a configuration of a content list file in a hard disk of a personal computer.
FIG. 26 is a first flowchart for explaining the operation of transferring the license for encrypted content data in the data distribution system shown in FIG. 1;
FIG. 27 is a second flowchart for explaining the operation of transferring the license for the encrypted content data in the data distribution system shown in FIG. 1;
FIG. 28 is a third flowchart for explaining the operation of transferring the license of the encrypted content data in the data distribution system shown in FIG.
FIG. 29 is a fourth flowchart for explaining the operation of transferring the license for the encrypted content data in the data distribution system shown in FIG. 1;
30 is a first flowchart for explaining a license checkout operation for encrypted content data in the data distribution system shown in FIG. 1; FIG.
FIG. 31 is a second flowchart for explaining the license checkout operation of the encrypted content data in the data distribution system shown in FIG. 1;
32 is a third flowchart for explaining the license checkout operation of the encrypted content data in the data distribution system shown in FIG. 1. FIG.
FIG. 33 is a fourth flowchart for explaining the license checkout operation of the encrypted content data in the data distribution system shown in FIG. 1;
FIG. 34 is a fifth flowchart for explaining the license checkout operation for the encrypted content data in the data distribution system shown in FIG. 1;
35 is a first flowchart for explaining a license check-in operation for encrypted content data in the data distribution system shown in FIG. 1; FIG.
FIG. 36 is a second flowchart for explaining the license check-in operation for encrypted content data in the data distribution system shown in FIG. 1;
FIG. 37 is a third flowchart for explaining the license check-in operation of the encrypted content data in the data distribution system shown in FIG. 1;
FIG. 38 is a fourth flowchart for explaining the license check-in operation of the encrypted content data in the data distribution system shown in FIG. 1;
FIG. 39 is a first flowchart for explaining a reproduction operation in the reproduction terminal.
FIG. 40 is a second flowchart for explaining the reproduction operation in the reproduction terminal.
41 is a first flowchart for explaining movement of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1. FIG.
42 is a second flowchart for explaining the transfer of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1. FIG.
43 is a third flowchart for explaining the transfer of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1. FIG.
44 is a fourth flowchart for explaining transfer of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1; FIG.
45 is a fifth flowchart for explaining transfer of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1; FIG.
46 is a sixth flowchart for explaining the transfer of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1; FIG.
47 is a seventh flowchart for explaining the transfer of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1; FIG.
48 is an eighth flowchart for explaining the transfer of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1. FIG.
FIG. 49 is a diagram showing another configuration of the content list file in the hard disk of the personal computer.
FIG. 50 is a first flowchart for explaining another operation for initializing the confidential file in the personal computer shown in FIG. 1;
51 is a second flowchart for explaining another operation for initializing the confidential file in the personal computer shown in FIG. 1. FIG.
FIG. 52 is a third flowchart for explaining another operation for initializing the confidential file in the personal computer shown in FIG. 1;
53 is a first flowchart for explaining another distribution operation with a low security level in the data distribution system shown in FIG. 1; FIG.
54 is a second flowchart for explaining another distribution operation with a low security level in the data distribution system shown in FIG. 1. FIG.
55 is a third flowchart for explaining another distribution operation with a low security level in the data distribution system shown in FIG. 1. FIG.
56 is a fourth flowchart for explaining another distribution operation with a low security level in the data distribution system shown in FIG. 1; FIG.
FIG. 57 is a first flowchart for explaining another operation of ripping in the data distribution system shown in FIG. 1;
FIG. 58 is a second flowchart for explaining another operation of ripping in the data distribution system shown in FIG. 1;
59 is a first flowchart for explaining another operation for checking out the license of the encrypted content data in the data distribution system shown in FIG. 1; FIG.
60 is a second flowchart for explaining another operation for checking out the license of the encrypted content data in the data distribution system shown in FIG. 1. FIG.
61 is a third flowchart for explaining another operation for checking out the license of the encrypted content data in the data distribution system shown in FIG. 1. FIG.
FIG. 62 is a fourth flowchart for explaining another operation for checking out the license of the encrypted content data in the data distribution system shown in FIG. 1;
FIG. 63 is a fifth flowchart for explaining another operation for checking out the license of the encrypted content data in the data distribution system shown in FIG. 1;
FIG. 64 is a first flowchart for explaining another operation of the license check-in of the encrypted content data in the data distribution system shown in FIG. 1;
65 is a second flowchart for explaining another operation of the license check-in of the encrypted content data in the data distribution system shown in FIG. 1. FIG.
66 is a third flowchart for explaining another operation of the license check-in of the encrypted content data in the data distribution system shown in FIG. 1. FIG.
67 is a fourth flowchart for explaining another operation of the license check-in of the encrypted content data in the data distribution system shown in FIG. 1. FIG.
68 is a first flowchart for explaining another movement of encrypted content data and a license between personal computers in the data distribution system shown in FIG. 1; FIG.
FIG. 69 is a second flowchart for explaining another movement operation between the encrypted content data and the license personal computer in the data distribution system shown in FIG. 1;
70 is a third flowchart for explaining another movement operation between the encrypted content data and the license personal computer in the data distribution system shown in FIG. 1; FIG.
71 is a fourth flowchart for explaining another transfer operation between the encrypted content data and the license personal computer in the data distribution system shown in FIG. 1; FIG.
72 is a fifth flowchart for explaining another transfer operation between the encrypted content data and the license personal computer in the data distribution system shown in FIG. 1; FIG.
73 is a sixth flowchart for explaining another movement operation between the encrypted content data and the license personal computer in the data distribution system shown in FIG. 1; FIG.
74 is a seventh flowchart for explaining another movement operation between the encrypted content data and the license personal computer in the data distribution system shown in FIG. 1; FIG.
[Explanation of symbols]
10 Distribution server, 20 Distribution carrier, 30 Internet network, 40 Modem, 50, 80 Personal computer, 60 CD, 70 USB cable, 90 Communication cable, 100 Playback terminal, 110 Memory card, 130 Headphone, 150 Content list file, 160 Encrypted confidential file, 302 charging database, 304 information database, 306 CRL database, 307 menu database, 308 distribution record database, 310 data processing unit, 312, 320, 1404, 1408, 1412, 1422, 1504, 1510, 1516, 5204 , 5208, 5212, 5222 Decryption processing unit, 313 Authentication key holding unit, 315 Distribution control unit, 316, Session key generation unit, 318, 326, 328, 1406 1410, 1417, 1506, 5206, 5210, 5217, 5405 Encryption processing unit, 350 communication device, 510, 1106, 1420, 5220 controller, 511 license management module, 520 license management device, 530 hard disk, 540 CD-ROM drive, 550 , 1112 USB interface, 560 keyboard, 570 display, 580, 1114, 1426, 1530, 5226 terminal, 1108 operation panel, 1110 display panel, 1200 memory card interface, 1400, 1500, 5200 authentication data holding unit, 1402, 5202 Kmc holding Part, 1414, 5214 KPa holding part, 1415, 5215 memory, 1415A, 5215A CRL region, 1415B, 5215 License area, 1415C data area, 1416, 5216 KPmc holding section, 1418, 5218 session key generating section, 1421, 5221 Km holding section, 1424, 5224 interface, 1442, 1446 changeover switch, 1502 Kp1 holding section, 1518 music playback section, 1519 DA converter, 1521-152n license management file, 1531-153n content file, 1550 content playback device.

Claims (17)

Encrypted content data obtained by encrypting content data and data for obtaining the original plaintext by decrypting the encrypted content data and outputting the encrypted content data and the license to another data terminal device A terminal device,
A module unit for acquiring the encrypted content data and the license by software;
A storage unit for storing the encrypted content data, the license management file, and the encrypted confidential file;
A device unit for decrypting the encrypted confidential file and storing a binding license including a binding key for encrypting the decrypted confidential file in a dedicated area;
The confidential file includes confidential information including the license as a component,
The license management file, in correspondence with the encrypted content data, and, viewed contains a management number of the confidential information contained in the confidential file,
When initializing the encrypted confidential file,
The module unit generates the binding license including the binding key, generates a confidential file with empty confidential information, encrypts the generated confidential file with the generated binding key, and generates the encrypted confidential file. And generating the generated binding license to the device unit,
When obtaining the license,
The module unit decrypts the encrypted confidential file read from the storage unit with the binding key acquired from the device unit, and writes the acquired license as confidential information in the decrypted confidential file. Update the secret file, encrypt the updated secret file with the binding key, update and record the encrypted encrypted secret file in the storage unit, and set the management number of the secret information including the written license as a constituent element. A data terminal device that creates a license management file including the file and writes the file to the storage unit . When sending the license,
2. The module unit according to claim 1, wherein the module unit acquires a license by decrypting the encrypted confidential file read from the storage unit with the binding key acquired from the device unit, and outputs the acquired license to the outside. Data terminal equipment. When the output of the license,
The data terminal device according to claim 2 , wherein the module unit outputs the encrypted content data and the license corresponding to the license and recorded in the storage unit to the outside . The data terminal device according to claim 1, wherein the device unit receives a dedicated registration number designating the dedicated area from the module unit, and stores the binding license in the dedicated area based on the received dedicated registration number . When outputting the license,
The data terminal apparatus according to claim 4, wherein the module unit acquires the binding key by transmitting the dedicated registration number to the device unit . When outputting the license,
The module unit transmits authentication data for the device unit to the device unit, and acquires the binding key when the authentication data is authenticated in the device unit. A data terminal device according to the item . When outputting the license,
The data terminal apparatus according to claim 1, wherein the device unit encrypts and outputs the binding key . When outputting the license,
The module unit acquires the confidential file by decrypting the encrypted confidential file with the acquired binding key, and the confidential information that matches the management number of the confidential information included in the license management file read from the storage unit The data terminal device according to claim 2, wherein a license to be output to the outside is obtained by reading out from the obtained confidential file . When sending the license to another data terminal device,
The module unit further confirms that the device unit can write a binding license by receiving the public encryption key held in the device unit. The data terminal device described in 1. When moving the encrypted content data to another data terminal device,
When the license cannot be copied, the module unit deletes the confidential information having the license transmitted to the other data terminal device as a component, deletes the management number of the deleted confidential information, and deletes the license management file. 9. The data terminal device according to claim 8 , wherein the data terminal device updates, generates another binding key, encrypts the confidential file with the generated another banding key, and updates the encrypted confidential file . When moving the encrypted content data to another data terminal device,
The device unit according to claim 10, wherein the device unit receives another binding license including the another binding key from the module unit, and stores the received another binding license by overwriting the dedicated area . Data terminal device. When sending the license to another data terminal device,
11. The data terminal device according to claim 1 , wherein when the authentication data received from the other data terminal device is authenticated , the module unit transmits a license to the other data terminal device. The data terminal device according to claim 12 , wherein the module unit outputs the license after encrypting the license . 14. The data terminal device according to claim 1, wherein the module unit acquires the encrypted content data and the license from a distribution server via the Internet . A medium driving unit for reading plaintext content data from the recording medium;
The module unit generates a license based on duplication permission / inhibition information included in the content data read by the medium driving unit, encrypts the content data with a license key included in the generated license, and generates encrypted content data. The data terminal device according to any one of claims 1 to 13, wherein the encrypted content data and the license are acquired by generation . The device unit further receives the encrypted content data and the license from the distribution server, holds the received license,
The data storage device according to any one of claims 1 to 13, wherein the storage unit stores encrypted content data received by the device unit. Encrypted content data obtained by encrypting content data and data for obtaining the original plaintext by decrypting the encrypted content data and outputting the encrypted content data and the license to another data terminal device A terminal device control method,
Obtaining the encrypted content data and the license by software;
Storing the encrypted content data, the license management file, and the encrypted confidential file in a storage unit;
Decrypting the encrypted confidential file and storing a binding license including a binding key for encrypting the decrypted confidential file in a dedicated area,
The confidential file includes confidential information including the license as a component,
The license management file corresponds to the encrypted content data and includes a management number of the confidential information included in the confidential file;
When the encrypted confidential file is initialized, the binding license including the binding key is generated, a confidential file with empty confidential information is generated, and the generated confidential file is encrypted with the generated binding key. Generating an encrypted sensitive file;
When the license is acquired, the stored encrypted confidential file is decrypted with the generated binding key, the acquired license is written as confidential information in the decrypted confidential file, and the confidential file is updated. A license management file including a management number of confidential information having the written license as a constituent element, wherein the updated confidential file is encrypted with the binding key, the encrypted encrypted confidential file is updated and recorded in the storage unit, and The method for controlling the data terminal device further comprising: creating and writing to the storage unit .

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