JP2010016887A - License information transmission apparatus, license information transmission program, license information transmission method and license information receiver, license information reception program, and license information reception method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a license information transmission apparatus, program and method, and a license information receiver, program and method capable of reliably transmitting and receiving license information without increasing the production cost and the operation cost. <P>SOLUTION: A license information transmission apparatus 1 for transmitting license information including information to permit use of contents and the contents, includes a license information generating section 5 for generating the license information and an encryption key for encrypting the contents; an encryption section 7 for encrypting the contents to obtain encrypted contents; an ECM/EMM generating section 9 for encrypting the license information by secret information to obtain encrypted license information; and a multiplexer section 11 for multiplexing the encrypted contents and the encrypted license information and providing an output of multiplexed contents. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a license information transmitting apparatus, a license information transmitting program, a license information transmitting method, a license information receiving apparatus, a license information receiving program, and license information that transmit and receive license information that is information permitting use of the content together with the content. It relates to the receiving method.

  Conventionally, in digital broadcasting, on the broadcast side (transmission side) that broadcasts video and audio content, the conditional access system defined in “Access Control System Standards in Digital Broadcasting” (see Non-Patent Document 1) is used. The content is scrambled (encrypted content) at the transport stream level and broadcast to prevent unauthorized reception on the receiving side. Also, in this digital broadcasting, on the receiving side that receives video / audio encrypted content, by using the limited playback method defined in Non-Patent Document 1, the received and stored encrypted content is reproduced and copied. , Preventing unauthorized playback and duplication.

  In the limited reproduction method used on the reception side, when reproducing the received and stored encrypted content, license information including a decryption key for decrypting the encrypted content is required. This license information is included in an ECM (Entitlement Control Message) multiplexed on the encrypted content, and is sent to the receiving side through broadcasting (by broadcast waves). The license information is sent to the receiving side through broadcasting (by broadcast waves) or by other means, separately from the encrypted content. For example, only the encrypted content is broadcasted first, and then the request for viewing the encrypted content is received from the receiver on the receiving side by means of a telephone, a postcard, etc. License information for decrypting the content is sent to the receiving side.

  However, in the conventional method of requesting license information by means of telephone or postcard, the viewer on the receiving side cannot view the encrypted content immediately after making a request to view the encrypted content. Can not obtain a satisfactory service (response speed from the request for viewing until the license information is sent). In other words, since the number of viewers (the number of households) requesting to view encrypted content is large, it takes time until the license information is processed on the broadcasting station side. The processing of license information on the broadcasting station side means that after receiving the viewing request, the decryption key can be individually acquired from the license information by the receiving side device owned by the viewer who has made the viewing request through broadcasting. Is to do. Incidentally, the number of viewers on the receiving side is more than 10 million.

  For this reason, a communication network such as the Internet or a broadband network is used to send license information to a receiving device owned by a viewer who has requested viewing of encrypted content without broadcasting (regardless of broadcast waves). Is used to receive a request for viewing encrypted content, and to transmit license information immediately after receiving the viewing request.

  One of the methods for transmitting license information immediately after receiving this viewing request is X. There is a TLS (Transport Layer Security) protocol utilization method that performs device authentication on the receiving side using a 509 certificate (public key information). This TLS protocol utilization method is a method of constructing a secure line on a communication network using the TLS protocol and transmitting license information safely. The TLS protocol is defined in RFC 2246 The TLS Protocol Version 1.0, which is a technical specification standardized by the Internet Engineering Task Force (IETF), and secures between a transmission side and a reception side on a communication network. Even if an attacker (a person who illegally acquires license information and tries to use it) intervenes between the connection on the sending side (connection point) and the connection on the receiving side (connection point) The information (license information) being transmitted / received cannot be acquired.

  Further, in the limited reception method and the limited reproduction method, an IC card called a CAS (Conditional Access System) card is provided in a receiving device, and individual secret information (master key Km or the like) is held for each IC card. In addition to realizing the limited reception function and the limited playback function, the security is improved by processing the key information in the IC card.

“Access Control System Standard for Digital Broadcasting” ARIB STD-B25 Published by The Radio Industries Association, February 6, 2003, all pages

  However, the conventional X. In the TLS protocol using method in which device authentication is performed using a 509 certificate (public key information), license information can be transmitted safely (highly secure), but a device that implements the TLS protocol must be manufactured. Don't be. In the limited reception method and the limited reproduction method, license information is not handled in the CAS card. For this reason, assuming a method in which these TLS protocol utilization methods, a limited reception method, and a limited reproduction method are mixed, it is necessary to implement the TLS protocol in the CAS card, but the TLS protocol must be implemented in the CAS card. Is technically difficult, and in addition to the CAS card, a security module (IC card) that implements the TLS protocol is required, which increases the production cost of the receiving device (the device becomes expensive). There is.

  In addition to the secret information (master key Km) held in the CAS card, X. There is a problem that it is necessary to manage the 509 certificate and the operation cost increases.

  Accordingly, an object of the present invention is to solve the problems of the conventional technology described above, and to transmit and receive the license information safely without increasing the production cost and the operating cost. To provide a transmission program, a license information transmission method, a license information reception device, a license information reception program, and a license information reception method.

In order to achieve the above-described object, the present invention has the following configuration.
The license information transmitting apparatus according to claim 1, wherein the license information transmitting apparatus transmits license information including information permitting use of the content and the content, and includes a license information generating unit, a content encrypting unit, a license An information encryption unit and a multiplexing output unit are provided.

  According to this configuration, the license information transmitting device decrypts the use condition information that sets the period during which the use of the content is permitted, the content ID that identifies the content, and the encrypted content obtained by encrypting the content, by the license information generation unit. License information including at least a decryption key and an encryption key for encrypting content are generated. Note that there is a one-to-one correspondence between the encryption key and the decryption key. For example, when the encryption key and the decryption key are generated using a common key encryption algorithm, they are the same. In addition, the usage condition information includes information that sets whether or not to allow fast-forward playback of content, in addition to a period during which content usage is permitted (viewing permission period).

  Subsequently, the license information transmitting apparatus uses the content encryption unit to convert the content with the encryption key generated by the license information generation unit into encrypted content, and the license information encryption unit transmits the license information on the receiving side. The encrypted license information is encrypted with the secret information held one-on-one with the device. This secret information is, for example, a master key Km held in advance in the security module (CAS card) of the receiving device. Then, the license information transmitting apparatus outputs the multiplexed content obtained by multiplexing the encrypted content and the encrypted license information by the multiplexed output unit.

  The license information transmission program according to claim 2, wherein a license information generation unit, a content encryption unit, a license information encryption unit, a multiplexing unit, and a device for transmitting the license information including information permitting use of the content and the content are multiplexed. The output unit is configured to function.

  According to this configuration, the license information transmission program decrypts the use condition information that sets the period during which the use of the content is permitted, the content ID that identifies the content, and the encrypted content obtained by encrypting the content, by the license information generation unit. The apparatus generates license information including at least a decryption key and an encryption key for encrypting content. Subsequently, the license information transmission program causes the content encryption unit to generate encrypted content obtained by encrypting the content with the encryption key generated by the license information generation unit, and the license information encryption unit receives the license information on the receiving side. The device is made to function so that the encrypted license information is encrypted with the secret information held one-on-one with the device. Then, the license information transmission program causes the multiplexed output means to output the multiplexed content obtained by multiplexing the encrypted content and the encrypted license information from the apparatus.

  A license information transmission method according to claim 3 is a license information transmission method for transmitting license information including information permitting use of content and the content, the license information generation step, the content encryption step, The procedure includes an information encryption step and a multiplexing output step.

  According to such a procedure, in the license information transmission method, in the license information generation step, usage condition information that sets a period during which content usage is permitted, a content ID that identifies content, and encrypted content obtained by encrypting content are decrypted. License information including at least a decryption key and an encryption key for encrypting content are generated. Subsequently, the license information transmission method uses encrypted content obtained by encrypting the content with the encryption key generated in the license information generation step in the content encryption step, and the license information is received on the receiving side in the license information encryption step. The encrypted license information is encrypted with the secret information held one-on-one with the device. In the license information transmission method, in the multiplexing output step, the multiplexed content obtained by multiplexing the encrypted content and the encrypted license information is output.

  The license information receiving device according to claim 4 receives the multiplexed content transmitted from the license information transmitting device according to claim 1, and the encrypted license information and the encrypted content multiplexed in the multiplexed content Information receiving apparatus that separates and decrypts the license information, and includes a reception separation unit, a license information processing unit, and a decryption output unit.

  According to this configuration, the license information receiving device receives the multiplexed content transmitted from the transmission-side license information transmitting device by the reception separating unit, and converts the multiplexed content into the encrypted license information and the encrypted content. To separate. Subsequently, the license information receiving device decrypts the encrypted license information with the secret information (for example, the master key Km, etc.) held one-to-one with the license information transmitting device by the license information processing means. Output the decryption key included in the license information. In the license information receiving apparatus, the decryption output unit outputs the content obtained by decrypting the encrypted content with the decryption key output by the license information processing unit.

  The license information receiving program according to claim 5 receives the multiplexed content transmitted from the device on the transmission side by the license information transmitting program according to claim 2, and is encrypted in the multiplexed content A device that separates and decrypts license information and encrypted content is configured to function as a reception separation unit, a license information processing unit, and a decryption output unit.

  According to this configuration, the license information receiving program causes the reception separating unit to receive the multiplexed content transmitted from the transmission-side device, and to separate the multiplexed content into the encrypted license information and the encrypted content. To make the device function. Subsequently, the license information receiving program causes the license information processing means to decrypt the encrypted license information with secret information (for example, the master key Km, etc.) held one-to-one with the device on the transmission side. The device is caused to function so as to output the decryption key included in the license information. The license information receiving program causes the apparatus to function so that the decrypted output unit outputs the content obtained by decrypting the encrypted content with the decryption key output by the license information processing unit.

  According to a sixth aspect of the present invention, there is provided a license information receiving method which receives the multiplexed content transmitted from the device on the transmission side by the license information transmitting method according to the third aspect, and is encrypted in the multiplexed content. A license information receiving method that separates and decrypts license information and encrypted content, and includes a reception separation step, a license information processing step, and a decryption output step.

  According to this procedure, the license information receiving method receives the multiplexed content transmitted from the device on the transmission side in the reception separation step, and separates the multiplexed content into encrypted license information and encrypted content. Subsequently, in the license information receiving method, in the license information processing step, the encrypted license information is decrypted with secret information (for example, a master key Km, etc.) held one-to-one with the device on the transmission side. Output the decryption key included in the license information. In the license information receiving method, in the decryption output step, the content obtained by decrypting the encrypted content with the decryption key output in the license information processing step is output.

The present invention has the following excellent effects.
According to the first, second, and third aspects of the invention, since the license information is encrypted using the secret information held one-to-one with the receiving device, the production cost and the operation cost are increased. License information can be transmitted securely.

  According to the fourth, fifth, and sixth aspects of the invention, the encryption license information is decrypted by using the secret information that is held one-to-one with the device on the transmission side, thereby increasing the production cost and the operation cost. The license information can be received safely without causing it to occur.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the license information transmission / reception system which is one embodiment by this invention (1st embodiment). It is a block diagram of the license information transmission / reception system which is one embodiment by this invention (2nd embodiment). It is a block diagram of the license information transmission / reception system which is one embodiment by this invention (3rd embodiment). It is a sequence chart explaining operation | movement of the license information transmission / reception system shown in FIG. It is a sequence chart explaining operation | movement of the license information transmission / reception system shown in FIG. It is a sequence chart explaining operation | movement of the license information transmission / reception system shown in FIG. It is the figure which showed the structural example of the MAC information addition encryption message. It is the figure which showed the structural example of EMM.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
In this embodiment, three embodiments of a license information transmission / reception system including a license information transmission device and a license information reception device (first embodiment, second embodiment, and third embodiment) First, the configuration of each license information transmission / reception system (
1 to 3), and then the overall operation of each license information transmission / reception system (including the operation of the license information transmitting apparatus and the operation of the license information receiving apparatus, FIGS. 4 to 6), and then A structural example (FIG. 7) of the MAC information addition encrypted message and a structural example of the EMM (FIG. 8) will be described.

(Configuration of License Information Transmission / Reception System First Embodiment)
FIG. 1 shows a block diagram of a license information transmission / reception system according to the first embodiment. As shown in FIG. 1, the license information transmission / reception system A includes a license information transmission device 1 (1A), a license information reception device 3 (3A), and contents decrypted by the license information reception device 3 (3A). And a display device 2 including a liquid crystal display, a CRT, and the like.

  This license information transmission / reception system A is a mode in which license information is distributed (transmitted) together with contents by broadcasting.

[Configuration of License Information Transmitting Apparatus First Embodiment]
The license information transmitting apparatus 1 (1A) includes encrypted content obtained by encrypting content including video / audio data, and encrypted license information obtained by encrypting license information including information permitting use (viewing) of the content. The license information generating unit 5 (license information generating unit), the encrypting unit 7 (content encrypting unit), and the ECM / EMM generating unit 9 (license information encrypting unit) are transmitted. ), A multiplexing unit 11 (multiplexing output means), and a secret information holding unit 13.

  The license information generation unit 5 generates an encryption key for encrypting content and also generates license information. The license information includes usage condition information that sets a period during which content usage is permitted, a content ID for identifying the content, and an encrypted content that is associated with the content ID and that is encrypted with an encryption key. And a decryption key for decrypting. Further, the usage condition information includes information such as whether or not fast-forward playback of the content and the copy limit number of the content are permitted, in addition to the period during which the content is permitted to be used (viewing permission period).

  For example, the license information is “02/06 / 2003-09 / 06/2003” (viewable from June 2, 2003 to June 9, 2003) as the viewing permission period of the use condition information. “Skip No” (cannot be fast-forwarded) as copyability, “Copy 3” (can be copied three times) as the maximum number of copies, “0000001” (6 bytes) as the content ID, and 128-bit key length And a decryption key possessed (when a common key encryption method is used).

  Further, the encryption key generated by the license information generation unit 5 is sequentially updated (changed) in units of seconds. For example, this encryption key is a scramble key Ks.

  The encryption unit 7 outputs the encrypted content obtained by encrypting the input content with the encryption key generated by the license information generation unit 5 to the multiplexing unit 11. In the encryption unit 7, when encrypting the content, an encryption key (scramble key Ks) to be changed in units of seconds is put in an ECM (Entlement Control Message; common information), and this ECM is stored in the license information generation unit 5. It may be encrypted with another generated encryption key and multiplexed with the encrypted content encrypted by the encryption unit 7.

  The ECM / EMM generation unit 9 encrypts the license information generated by the license information generation unit 5 with the secret information held (recorded) by the secret information holding unit 13, and multiplexes the encrypted encrypted license information. Is output to the conversion unit 11. The ECM / EMM generation unit 9 corresponds to the license information encryption unit described in the claims. In this embodiment, the encryption license information is multiplexed as ECM or EMM (Entlement Management Message; individual information). 11 is output.

  The multiplexing unit 11 outputs the multiplexed content obtained by multiplexing the encrypted content output from the encryption unit 7 and the encrypted license information output from the ECM / EMM generation unit 9. In this embodiment, the multiplexed content output from the multiplexing unit 11 is delivered while being superimposed on the broadcast wave.

  The secret information holding unit 13 holds all the same secret information as the secret information individually held in the license information receiving apparatus 3 (3A) on the receiving side. That is, secret information associated with the device number assigned to each license information receiving device 3 (3A) is held.

  The secret information is a master key Km or the like recorded in a security module (IC card or the like) provided in the license information receiving device 3 (3A) on the receiving side. However, when the master key Km is used for the secret information, the license information must be encrypted and transmitted using the same master key Km as the master key Km provided for each license information receiving apparatus 3 (3A) on the receiving side. I must. In other words, license information (encrypted license information) must be distributed (transmitted) to all license information receiving apparatuses 3 (3A) that permit the use of content, resulting in a large amount of license information distributed. turn into. Therefore, in order to reduce the distribution amount of the license information, secret information called a work key Kw encrypted in advance using the master key Km is preliminarily sent to the license information receiving apparatus 3 (3A) that permits the reception of the license information. Further, the license information (encrypted license information) may be stored in the ECM or EMM and encrypted using the work key Kw.

  According to the license information transmitting apparatus 1 (1A) described in the first embodiment, the license information generating unit 5 generates license information and an encryption key. Subsequently, the encrypted content is encrypted by the encryption unit 7 using the encryption key generated by the license information generation unit 5, and the license information is encrypted by the ECM / EMM generation unit 9 with the secret information. This is encrypted license information. The multiplexing unit 11 outputs the multiplexed content in which the encrypted content and the encrypted license information are multiplexed. For this reason, since the license information is encrypted using the secret information held one-to-one with the license information receiving device 3 (3A) on the receiving side, the license information is not increased without increasing the production cost and the operating cost. Can be sent safely.

[Configuration of License Information Receiving Device First Embodiment]
The license information receiving device 3 (3A) receives the multiplexed content transmitted from the license information transmitting device 1 (1A), and displays the content obtained by decrypting the encrypted content included in the multiplexed content on the display device 2. The output unit includes a reception separation unit 15 (reception separation unit), a security module 17, and a decryption unit 19 (decryption output unit).

  The reception separating unit 15 receives the multiplexed content distributed (transmitted) from the license information transmitting device 1 (1A), and separates the encrypted content included in the multiplexed content and the encrypted license information. Thus, the encrypted license information is output to the security module 17, and the encrypted content is output to the decryption unit 19.

  The security module 17 is a module having tamper resistance, and includes a license information processing unit 21 (license information processing means) and a secret information holding unit 23. The security module 17 is composed of an IC card or the like, and corresponds to a conventional CAS card.

The license information processing unit 21 processes the encrypted license information output from the reception separation unit 15. That is, the encrypted license information is decrypted with the secret information held (recorded) in the secret information holding unit 23, and the decryption key included in the decrypted license information is output to the decryption unit 19.

  The secret information holding unit 23 holds (records) common (same) secret information as the secret information held in the license information transmitting apparatus 1 (1A) on the transmission side. This secret information is, for example, the master key Km or the work key Kw.

  The decryption unit 19 outputs the content obtained by decrypting the encrypted content output from the reception separation unit 15 with the decryption key output from the license information processing unit 21 of the security module 17 to the outside of the device 3 (3A). It is. In this embodiment, the content is output to the display device 2 and displayed on the display device 2.

  According to the license information receiving device 3 (3A) described in the first embodiment, the reception separating unit 15 receives the multiplexed content transmitted from the license information transmitting device 1 (1A) on the transmission side, This multiplexed content is separated into encrypted license information and encrypted content. Subsequently, the license information processing unit 21 decrypts the encrypted license information with the secret information (for example, the master key Km) held one-on-one with the license information transmitting apparatus 1 (1A), and the decrypted license The decryption key included in the information is output. Then, the decryption unit 19 decrypts the encrypted content with the decryption key output from the license information processing unit 21 and outputs the decrypted content. For this reason, since the encrypted license information is decrypted using the secret information held one-to-one with the license information transmitting apparatus 1 (1A) on the transmission side, without increasing the production cost and the operation cost, License information can be received securely.

(Configuration of License Information Transmission / Reception System Second Embodiment)
Next, FIG. 2 shows a block diagram of a license information transmission / reception system according to the second embodiment. As shown in FIG. 2, the license information transmission / reception system B has a license information transmission apparatus 1 (1B), a license information reception apparatus 3 (3B), and contents decrypted by the license information reception apparatus 3 (3B). And a display device 2 composed of a liquid crystal display, a CRT, or the like.

  This license information transmission / reception system B is a mode in which content (encrypted content) is distributed by broadcasting and license information (encrypted license information) is transmitted via a communication network.

[Configuration of License Information Transmitter Second Embodiment]
The license information transmission device 1 (1B) includes a license information generation unit 5, an encryption unit 7 (content encryption transmission unit), a secret information holding unit 13, an EMM generation unit 25 (license information encryption unit), And a device authentication unit 27. Among the configurations of the license information transmitting apparatus 1 (1B), those described in the configuration of the license information transmitting apparatus 1 (1A) shown in FIG. To do.

  The EMM generation unit 25 outputs the license information output from the license information generation unit 5 with the secret information stored in the secret information storage unit 13 to the device authentication unit 27 as EMM. Is.

  The device authentication unit 27 generates a MAC information addition encrypted message to authenticate the receiving device (in this case, the license information receiving device 3 (3B)), and sends the message via the communication network. The transmission unit includes a message generation unit 29 (message generation unit) and a communication unit 31 (communication unit).

  The message generation unit 29 generates an encrypted message obtained by encrypting the encryption license information (entered in the EMM variable unit) generated by the EMM generation unit 25 as an EMM, and the message is sent to the message MAC information-added encrypted message to which MAC information for detecting tampering is added is generated.

  In this MAC information addition encryption message generation method, first, the message generation unit 29 is connected to the receiving side license information receiving apparatus 3 (3B) via the communication unit 31 and the communication network (session establishment). A random number is generated. Subsequently, the random number generated by the license information receiving device 3 (3B) is acquired via the communication network and the communication unit 31, and based on the acquired random number, the generated random number, and the secret information, Generate a session key and a MAC key.

  Then, the EMM generation unit 25 generates an encrypted message obtained by encrypting the encrypted license information generated in the EMM (entered in the variable part of the EMM) with the session key, and the MAC information based on the MAC key. Create a MAC information-added encrypted message by adding MAC information to the encrypted message.

  Here, the session key is here (second embodiment and third embodiment) when connected to the license information receiving apparatus 3 (3B) on the receiving side via the communication network (when the session is established). The device 1 (1B) and the license information receiving device 3 (3B) exchange generated random numbers, take a hash value of the combined random number and secret information, and take several bytes of the hash value It is data of.

  In this case (second embodiment and third embodiment), the MAC key is associated with the license information receiving apparatus 3 (3B) on the receiving side via a communication network (when a session is established). The generated random numbers are exchanged between the device 1 (1B) and the license information receiving device 3 (3B), and the exchanged random number, secret information, and security module 35 provided in the license information receiving device 3 (3B) (described later) The hash value of the combination of the ID (module ID) is taken, and this hash value is data of several bytes. The MAC information is added to the end of the encrypted message.

This MAC information addition encryption message is information for performing device authentication of the license information receiving device 3 (3B) on the receiving side. That is, in order to decrypt the encrypted message that is a part of the MAC information-added encrypted message, the secret information is necessary, and if the unauthorized receiver does not know the secret information, the encrypted license information is obtained. The module ID that is currently used for broadcasting without obtaining any secret information via the communication network (that is, the message cannot be exchanged correctly with the license information receiving device 3 (3B) on the receiving side). If the master key Km is managed with the 1 (1B), only the license information receiving device 3 (3B) having the correct security module 35 (described later) can exchange messages.

  As a result, it is sufficient to manage the module ID currently used for broadcasting, the master key Km, and the secret information used for device authentication, so the function of distributing the license information via the communication network is transmitted. Even if added to the side, an increase in operation cost can be suppressed.

  The communication unit 31 transmits the MAC information addition encryption message generated by the message generation unit 29 via the communication network, and also receives the random number generated by the license information receiving device 3 (3B) on the receiving side. Is output to the message generator 29.

  According to the license information transmitting apparatus 1 (1B) described in the second embodiment, the license information generating unit 5 generates license information and an encryption key for encrypting content. Subsequently, encrypted content obtained by encrypting the content with the encryption key generated by the license information generation unit 5 is transmitted by the encryption unit 7, and the license information is encrypted by the EMM generation unit 25 using the secret information. This is encrypted license information.

  In addition, the message generation unit 29 generates a session key and a MAC key based on the secret information, and the encrypted license information encrypted by the EMM generation unit 25 is converted into an encrypted message encrypted with the session key. Then, the MAC information addition encrypted message to which the MAC information generated using the MAC key is added is generated. Then, the MAC information-added encrypted message is transmitted by the communication unit 31. For this reason, since the license information is encrypted and transmitted via the communication network using the secret information held one-to-one with the license information receiving device 3 (3B) on the receiving side, the license information receiving device 3 The license information can be transmitted safely without increasing the production cost and operation cost of (3B).

[Configuration of License Information Receiving Device Second Embodiment]
The license information receiving apparatus 3 (3B) includes a communication unit 33 (communication unit), a security module 35, and a decryption unit 19 (reception decryption unit). Among the configurations of the license information receiving device 3 (3B), those described in the configuration of the license information receiving device 3 (3A) shown in FIG. To do.

  The communication unit 33 receives the MAC information addition encryption message transmitted from the license information transmission apparatus 1 (1B) on the transmission side via the communication network.

  The security module 35 is a module having tamper resistance, and includes a message analysis unit 37 (message analysis unit), a license information processing unit 21 (license information processing unit), and a secret information holding unit 23.

  The message analysis unit 37 analyzes the MAC information addition encrypted message output from the communication unit 33, and outputs the encrypted license information to the license information processing unit 21 as an EMM.

  In this MAC information addition encrypted message analysis method, first, the message analysis unit 37 is connected to the license information transmission apparatus 1 (1B) on the transmission side via the communication unit 33 and the communication network (session establishment). A random number is generated. Subsequently, the random number generated by the license information transmitting apparatus 1 (1B) is acquired via the communication network and the communication unit 33, and based on the acquired random number, the generated random number, and the secret information, Generate a session key and a MAC key.

  Then, the MAC information is detected from the MAC information-added encrypted message received by the communication unit 33 using the MAC key, and the encrypted message is separated (extracted) from the MAC information-added encrypted message. Then, the encrypted license information obtained by decrypting the encrypted message with the session key is acquired and output to the license information processing unit 21.

  Here, the session key is here (second embodiment and third embodiment) when connected to the license information transmitting apparatus 1 (1B) on the transmission side via the communication network (when the session is established). The device 3 (3B) and the license information transmitting device 1 (1B) exchange generated random numbers, take a hash value of the combined random number and secret information, and take several bytes of the hash value It is data of.

  In this case (second embodiment and third embodiment), the MAC key is associated with the license information transmitting apparatus 1 (1B) on the transmission side via a communication network (when a session is established). The generated random numbers are exchanged between the device 3 (3B) and the license information transmitting device 1 (1B), and the exchanged random number, the secret information, and the ID (manufacturing number) of the security module 35 provided in the device 3 (3B). The hash value of a combination of the identification information set in advance and the like is taken, and data of several bytes of the hash value is obtained.

  In addition, the communication unit 33 and the message analysis unit 37 play the same role as the device authentication unit 27 of the license information transmission device 1 (1B) on the transmission side.

  According to the license information receiving device 3 (3B) described in the second embodiment, the MAC information additional encryption transmitted from the license information transmitting device 1 (1B) by the communication unit 33 via the communication network. When the message is received, the message analysis unit 37 generates a session key and a MAC key based on the secret information held one-on-one with the license information transmitting apparatus 1 (1B), and uses the session key and the MAC key. Then, an encrypted message is detected from the MAC information-added encrypted message, and encrypted license information obtained by decrypting the detected encrypted message with the session key is acquired.

  Then, the license information processing unit 21 decrypts the encrypted license information with the secret information (for example, the master key Km), and outputs the decryption key included in the decrypted license information. The received encrypted content is decrypted with the decryption key output from the license information processing unit 21, and the decrypted content is output. For this reason, since the encrypted license information received via the communication network is decrypted using the secret information held one-to-one with the license information transmitting apparatus 1 (1B) on the transmission side, the production cost and The license information can be received safely without increasing the operating cost.

(Configuration of License Information Transmission / Reception System Third Embodiment)
Next, FIG. 3 shows a block diagram of a license information transmission / reception system according to the third embodiment. As shown in FIG. 3, the license information transmission / reception system C includes a license information transmission apparatus 1 (1C), a license information reception apparatus 3 (3C), and contents decrypted by the license information reception apparatus 3 (3C). And a display device 2 including a liquid crystal display, a CRT, and the like.

  The license information transmission / reception system C distributes content (encrypted content) and license information (encrypted license information) by broadcasting, and transmits license information (encrypted license information) via a communication network. It is an aspect.

[Configuration of License Information Transmitting Apparatus Third Embodiment]
The license information transmitting apparatus 1 (1C) includes a license information generation unit 5, an encryption unit 7 (content encryption unit), an ECM / EMM generation unit 9, a multiplexing unit 11, a secret information holding unit 13, And a device authentication unit 27. Among the configurations of the license information transmitting apparatus 1 (1C), those described in the configuration of the license information transmitting apparatus 1 (1A) shown in FIG. 1 and the license information transmitting apparatus 1 (1B) shown in FIG. The components described in the configuration are denoted by the same reference numerals, and the description thereof is omitted.

  The ECM / EMM generating unit 9 of the license information transmitting apparatus 1 (1C) outputs the encrypted license information obtained by encrypting the license information with the secret information to the multiplexing unit 11 as ECM or EMM. The message generator 29 outputs the message as an EMM.

  According to the license information transmitting apparatus 1 (1C) described in the second embodiment, the license information generating unit 5 generates license information and an encryption key for encrypting content. Subsequently, the content is encrypted by the encryption unit 7 using the encryption key generated by the license information generation unit 5, and the ECM / EMM generation unit 9 receives the license information reception device 3 ( 3C) and encrypted license information encrypted with secret information held one-on-one, and is output to the multiplexing unit 11 as an ECM or EMM and also output to the message generation unit 29 as an EMM.

  The message generation unit 29 generates a session key and a MAC key based on the secret information, and uses the encrypted license information encrypted by the ECM / EMM generation unit 9 and the generated MAC key. MAC information is generated, the MAC information is added to the end of the encrypted license information, and the added information is encrypted with the session key to generate a MAC information addition encryption message. The MAC information addition encrypted message is transmitted by the communication unit 31 via the communication network.

  Also, the multiplexing unit 11 multiplexes the encrypted content and the encrypted license information, and outputs this multiplexed content. For this reason, the license information is encrypted using the secret information held one-to-one with the license information receiving device 3 (3C) on the receiving side, and is transmitted via the broadcast and the communication network. License information can be transmitted safely without increasing production costs and operational costs.

[Configuration of License Information Receiving Device Third Embodiment]
The license information receiving device 3 (3C) includes a reception separation unit 15, a decryption unit 19 (decryption unit), a communication unit 33 (communication unit), and a security module 35. Among the configurations of the license information receiving device 3 (3C), those described in the configuration of the license information receiving device 3 (3A) shown in FIG. 1 and the license information receiving device 3 (3B) shown in FIG. The components described in the configuration are denoted by the same reference numerals, and the description thereof is omitted.

  The license information processing unit 21 of the license information receiving device 3 (3C) includes the encrypted license information (ECM or EMM) separated by the reception separating unit 15 and the encrypted license information output from the message analyzing unit 37. (EMM) is decrypted, and the decryption key included in the decrypted license information is output to the decryption unit 19.

  According to the license information receiving device 3 (3C) described in the third embodiment, the MAC information-added encrypted message transmitted from the transmission-side license information transmitting device 1 (1C) by the communication unit 33 is: A session key and a MAC key are generated by the message analysis unit 37 based on the secret information received in a one-to-one relationship with the license information transmitting apparatus 1 (1C) by using the MAC key. Then, an encrypted message is detected from the MAC information-added encrypted message received by the communication unit 33, and encrypted license information obtained by decrypting the detected encrypted message with the session key is acquired.

  Further, the reception separating unit 15 receives the multiplexed content transmitted from the license information transmitting apparatus 1 (1C) on the transmission side, and the multiplexed content is separated into the encrypted license information and the encrypted content. Then, any one of the encrypted license information separated by the license separation unit 15 by the license information processing unit 21 and the encrypted license information acquired by the message analysis unit is stored as secret information (for example, a master key Km or the like). And the decryption key included in any of the decrypted license information is output. Thereafter, the decryption unit 19 outputs the content obtained by decrypting the encrypted content with the decryption key output from the license information processing unit 21. For this reason, the encrypted license information obtained via the broadcast and communication network is decrypted using the secret information held one-on-one with the license information transmitting device 1 (1C) on the transmission side. The license information can be received safely without increasing production costs and operation costs.

(Overall Operation of License Information Transmission / Reception System First Embodiment)
Next, referring to the sequence chart shown in FIG. 4, the overall operation of license information transmission / reception system A (including the operation of license information transmission device 1 (1A) and the operation of license information reception device 3 (3A)). This will be described (see FIG. 1 as appropriate).

  First, the license information generation unit 5 of the license information transmitting apparatus 1 (1A) generates license information and an encryption key (A1). Subsequently, the content input by the encryption unit 7 is encrypted with the encryption key generated by the license information generation unit 5 to obtain encrypted content (A2). In addition, the license information generated by the license information generation unit 5 in the ECM / EMM generation unit 9 is encrypted with the secret information held in the secret information holding unit 13 to obtain encrypted license information (A3).

  The multiplexing unit 11 multiplexes the encrypted content encrypted by the encryption unit 7 and the encrypted license information encrypted by the ECM / EMM generation unit 9 and outputs the multiplexed content. (Broadcast).

  Then, in the license information receiving device 3 (3A), the multiplexed content is received by the reception separating unit 15, the multiplexed content is separated into the encrypted content and the encrypted license information, and the encrypted content is decrypted by the decrypting unit 19. The encrypted license information is output to the license information processing unit 21 of the security module 17 (B1).

  In the security module 17, the license information processing unit 21 decrypts the encrypted license information with the secret information held in the secret information holding unit 23, obtains the license information, and the decryption key included in the license information Is output to the decoding unit 19 (C1).

  Thereafter, in the license information receiving device 3 (3A), the decryption unit 19 decrypts the encrypted content with the decryption key output from the license information processing unit 21, and outputs the decrypted content as content to the external display device 2 ( B2).

  As described in the operation of the license information transmission / reception system A, the secret information held in one-to-one correspondence between the license information transmission device 1 (1A) on the transmission side and the license information reception device 3 (3A) on the reception side. License information is encrypted and decrypted, and this secret information is used together with broadcast content that encrypts and decrypts content, so it can be handled safely without increasing the operating cost of this license information. it can.

(Overall Operation of License Information Transmission / Reception System Second Embodiment)
Next, referring to the sequence chart shown in FIG. 5, the overall operation of the license information transmission / reception system B (including the operation of the license information transmission device 1 (1B) and the operation of the license information reception device 3 (3B)). This will be described (see FIG. 2 as appropriate).

  First, the license information generation unit 5 of the license information transmitting apparatus 1 (1B) generates license information and an encryption key (A11). Subsequently, the content input by the encryption unit 7 is encrypted with the encryption key generated by the license information generation unit 5 to be an encrypted content, which is output (broadcast) (A12). Further, the EMM generation unit 25 encrypts the license information generated by the license information generation unit 5 with the secret information held in the secret information holding unit 13 to obtain encrypted license information (A13).

  When the encrypted content output (broadcast) from the license information transmission device 1 (1B) is received by the decryption unit 19 of the license information reception device 3 (3B), the license information reception device 3 (3B) (not shown) is omitted. The license information generation request data is output from the control unit to the message analysis unit 37 of the security module 35 via the communication unit 33 (B11). Then, the message analysis unit 37 of the security module 35 generates a card ID (security module ID) instruction and a random number R1 and outputs them to the communication unit 33 (C11).

  Then, authentication request data (including the card ID and the random number R1) is transmitted from the communication unit 33 of the license information receiving apparatus 3 (3B) to the license information transmitting apparatus 1 (1B) (B12). Then, the authentication request data is received by the communication unit 31 of the device authentication unit 27 of the license information transmitting apparatus 1 (1B), the random number R2 is generated by the message generation unit 29, and the generated random number R2 and the received random number A session key is generated based on R1 and the secret information. Further, a MAC key is generated based on the random number R1, the random number R2, the secret information, and the card ID, and authentication response data (including the random number R2) is stored in the device. It is transmitted from the communication unit 31 of the authentication unit 27 (A14).

  Then, the authentication response data is received by the communication unit 33 of the license information receiving apparatus 3 (3B) (B13) and output to the message analysis unit 37 of the security module 35. Then, the message analysis unit 37 of the security module 35 generates a session key based on the random number R1, the random number R2, and the secret information, and generates a MAC key based on the random number R1, the random number R2, the secret information, and the card ID. Is output to the communication unit 33 (C12).

  Then, a content ID is instructed from the communication unit 33 to the security module 35 (B14), MAC information is generated based on the content ID and the MAC key, and a MAC information-added encrypted message is generated (C13).

  Then, license information transmission request data is transmitted from the communication unit 33 of the license information receiving device 3 (3B) to the communication unit 31 of the device authentication unit 27 of the license information transmitting device 1 (1B) via the communication network. (B15). Then, the license information transmitting apparatus 1 (1B) generates and transmits an EMM (MAC information addition encrypted message) including the encrypted license information (A15).

  Then, the MAC information-added encrypted message is received by the communication unit 33 of the license information receiving device 3 (3B) (B16) and output to the message analysis unit 37 of the security module 35. The message analysis unit 37 decrypts the MAC information-added encrypted message with the secret information, verifies the MAC information, and acquires the encrypted license information. The encrypted license information is decrypted with the secret information, and the decryption key is output to the decryption unit 19 (C15).

  Thereafter, the decryption unit 19 of the license information receiving device 3 (3B) decrypts the encrypted content with the decryption key to become the content, and the content is output to the external display device 2 (B17).

  As described in the operation of the license information transmission / reception system B, the secret information held in one-to-one correspondence between the transmission-side license information transmission device 1 (1B) and the reception-side license information reception device 3 (3B). The license information is encrypted and decrypted, and only the license information is transmitted via the communication network. Since this secret information is used together with the broadcast for encrypting and decrypting the content, it can be handled safely without increasing the operating cost of this license information.

(Overall Operation of License Information Transmission / Reception System Third Embodiment)
Next, referring to the sequence chart shown in FIG. 6, the overall operation of the license information transmission / reception system C (including the operation of the license information transmission device 1 (1C) and the operation of the license information reception device 3 (3C)). This will be described (see FIG. 3 as appropriate).

  First, the license information generating unit 5 of the license information transmitting apparatus 1 (1C) generates license information and an encryption key (A21). Subsequently, the content input by the encryption unit 7 is encrypted with the encryption key generated by the license information generation unit 5 to obtain encrypted content (A22). Also, the ECM / EMM generation unit 9 encrypts the license information generated by the license information generation unit 5 with the secret information held in the secret information holding unit 13 to obtain encrypted license information (A23). .

  The multiplexing unit 11 multiplexes the encrypted content encrypted by the encryption unit 7 and the encrypted license information encrypted by the ECM / EMM generation unit 9 and outputs the multiplexed content. (Broadcast) (A24).

  Then, in the license information receiving device 3 (3C), the multiplexed content is received by the reception separating unit 15, the multiplexed content is separated into the encrypted content and the encrypted license information, and the encrypted content is decrypted by the decrypting unit 19. The encrypted license information is output to the license information processing unit 21 of the security module 35 (B21).

  When the encrypted content output (broadcast) from the license information transmission apparatus 1 (1C) is received by the decryption unit 19 of the license information reception apparatus 3 (3C), the license information reception apparatus 3 (3C) (not shown) is omitted. The license information generation request data is output from the control unit to the message analysis unit 37 of the security module 35 via the communication unit 33 (B22). Then, the message analysis unit 37 of the security module 35 generates a card ID (security module ID) instruction and a random number R1 and outputs them to the communication unit 33 (C21).

  Then, authentication request data (including the card ID and the random number R1) is transmitted from the communication unit 33 of the license information receiving apparatus 3 (3C) to the license information transmitting apparatus 1 (1C) (B23). Then, the authentication request data is received by the communication unit 31 of the device authentication unit 27 of the license information transmitting apparatus 1 (1C), the random number R2 is generated by the message generation unit 29, and the generated random number R2 and the received random number A session key is generated based on R1 and the secret information. Further, a MAC key is generated based on the random number R1, the random number R2, the secret information, and the card ID, and authentication response data (including the random number R2) is stored in the device. It is transmitted from the communication unit 31 of the authentication unit 27 (A25).

  Then, the authentication response data is received by the communication unit 33 of the license information receiving apparatus 3 (3C) (B24) and output to the message analysis unit 37 of the security module 35. Then, the message analysis unit 37 of the security module 35 generates a session key based on the random number R1, the random number R2, and the secret information, and generates a MAC key based on the random number R1, the random number R2, the secret information, and the card ID. Is output to the communication unit 33 (C22).

  Then, the content ID is instructed from the communication unit 33 to the security module 35 (B25), MAC information is generated based on the content ID and the MAC key, and a MAC information-added encrypted message (for verification) is generated ( C23). The MAC information addition encryption message (for verification) is generated based on license information (individual contract information) stored in advance in a storage unit (not shown) of the security module 35. This is for comparison with the MAC information-added encrypted message transmitted from the license information transmitting apparatus 1 (1C) on the transmission side. Then, after the MAC information addition encrypted message (for verification) is generated, a generation completion signal is output to the communication unit 33.

  Then, license information transmission request data is transmitted from the communication unit 33 of the license information receiving device 3 (3C) to the communication unit 31 of the device authentication unit 27 of the license information transmitting device 1 (1C) via the communication network. (B26). Then, the license information transmitting apparatus 1 (1C) generates and transmits an EMM (MAC information addition encrypted message) including the encrypted license information (A26).

  Then, the MAC information-added encrypted message is received by the communication unit 33 of the license information receiving apparatus 3 (3C) (B27) and output to the message analysis unit 37 of the security module 35. The message analysis unit 37 decrypts the MAC information-added encrypted message with the secret information, verifies the MAC information, and acquires the encrypted license information. The encrypted license information is decrypted with the secret information, and the decryption key is output to the decryption unit 19 (C25).

  Thereafter, the decryption unit 19 of the license information receiving device 3 (3C) decrypts the encrypted content with the decryption key to become the content, and the content is output to the external display device 2 (B28).

  As described in the operation of the license information transmission / reception system C, the secret information held in one-to-one correspondence between the license information transmission device 1 (1C) on the transmission side and the license information reception device 3 (3C) on the reception side. The license information is encrypted and decrypted, and the license information is transmitted via broadcasting and a communication network. Since this secret information is used together with the broadcast for encrypting and decrypting the content, it can be handled safely without increasing the operating cost of this license information.

(Example of structure of MAC information-added encrypted message)
Next, with reference to FIG. 7, a structural example of the MAC information-added encrypted message will be described. FIG. 7 shows an example of the structure of the MAC information-added encrypted message. As shown in FIG. 7, the MAC information-added encrypted message includes a non-encrypted part and an encrypted part.

  The non-encrypting unit includes a protocol number indicating a communication protocol number, and a session ID for identifying a session when the license information transmitting device 1 and the license information receiving device 3 are connected via the communication network. ing.

  The encryption unit includes a message including encryption license information and MAC information (MAC in FIG. 7) generated from the MAC key.

(EMM structure example)
Next, a structural example of the EMM will be described with reference to FIG. FIG. 8 shows an example of the structure of the EMM. As shown in FIG. 8, the EMM section includes an EMM section header describing an EMM section, license information and contract information, and a plurality of EMMs encrypted with secret information (master key Km). It is composed of a main body and a section CRC which is an error correction code of the EMM section.

  Also, the EMM main body receives an EMM (from the transmission side), an EMM fixing unit for entering a card ID (security module ID), a protocol number, etc. held by the license information receiving device 3, and license information And an EMM variable part for storing contract information, and falsification detection (falsification detection) for detecting falsification of the EMM section.

As mentioned above, although this invention was demonstrated based on three embodiment, this invention is not limited to this.
For example, the processing of each configuration of the license information transmission device 1 and the license information reception device 3 can be regarded as a license information transmission program and a license information reception program described in a general-purpose computer language. It can be regarded as a license information transmission method and a license information reception method that are regarded as respective processes. In these cases, the same effects as those of the license information transmitting apparatus 1 and the license information receiving apparatus 3 can be obtained.

DESCRIPTION OF SYMBOLS 1 License information transmission apparatus 3 License information reception apparatus 5 License information generation part (license information generation means)
7 Encryption unit (content encryption means, content encryption transmission means)
9 ECM / EMM generator (license information encryption means)
11 Multiplexer (Multiplexing output means)
13, 23 Secret information holding unit 15 Reception separation unit (reception separation means)
17, 35 Security module 19 Decryption unit (decryption output means)
21 License information processing section (license information processing means)
25 EMM generator (license information encryption means)
27 Device Authentication Unit 29 Message Generation Unit (Message Generation Unit)
31, 33 Communication unit (communication means)
37 Message analysis unit (message analysis means)

Claims (6)

A license information transmitting device that transmits license information including information permitting use of content and the content,
Use condition information that sets a period during which use of the content is permitted, content ID that identifies the content, license information that includes at least a decryption key that decrypts the encrypted content, and encrypts the content A license information generating means for generating an encryption key;
A content encryption unit that encrypts the content with the encryption key generated by the license information generation unit to obtain an encrypted content;
A license information encrypting unit that encrypts the license information with secret information held one-to-one with a device on the receiving side to obtain encrypted license information;
Multiplexed output means for multiplexing the encrypted content encrypted by the content encryption means and the encrypted license information encrypted by the license information encryption means, and outputting the multiplexed content;
A license information transmitting apparatus comprising: A device that transmits license information including information that permits use of the content and the content,
Use condition information that sets a period during which use of the content is permitted, content ID that identifies the content, license information that includes at least a decryption key that decrypts the encrypted content, and encrypts the content A license information generating means for generating an encryption key;
A content encryption unit that encrypts the content with the encryption key generated by the license information generation unit to obtain an encrypted content;
A license information encryption unit that encrypts the license information with secret information held one-to-one with a receiving device and sets the license information as encrypted license information;
Multiplexed output means for multiplexing the encrypted content encrypted by the content encrypting means and the encrypted license information encrypted by the license information encrypting means, and outputting the multiplexed content.
A license information transmission program that functions as: A license information transmission method for transmitting license information including information permitting use of content and the content,
Use condition information that sets a period during which use of the content is permitted, content ID that identifies the content, license information that includes at least a decryption key that decrypts the encrypted content, and encrypts the content A license information generation step for generating an encryption key;
A content encryption step of encrypting the content with the encryption key generated in the license information generation step to obtain an encrypted content;
A license information encryption step in which the license information is encrypted with secret information held on a one-to-one basis with a device on the receiving side to obtain encrypted license information;
A multiplexed output step of multiplexing the encrypted content encrypted in the content encryption step and the encrypted license information encrypted in the license information encryption step and outputting the multiplexed content as multiplexed content;
Including a license information transmission method. A license information receiving apparatus that receives multiplexed content transmitted from the license information transmitting apparatus according to claim 1, and separates and decrypts encrypted license information and encrypted content multiplexed in the multiplexed content Because
Receiving and separating means for receiving the multiplexed content and separating the encrypted license information and the encrypted content;
The license information for decrypting the encrypted license information separated by the reception separating means with the secret information held one-on-one with the license information transmitting device and outputting the decryption key included in the decrypted license information Processing means;
Decryption output means for decrypting the encrypted content with the decryption key output by the license information processing means and outputting the content;
A license information receiving apparatus comprising: The license information transmission program according to claim 2 receives the multiplexed content transmitted from the transmission side device, and separates the encrypted license information and the encrypted content multiplexed in the multiplexed content. The device to decrypt,
Receiving and separating means for receiving the multiplexed content and separating it into the encrypted license information and the encrypted content;
The license information for decrypting the encrypted license information separated by the reception separating means with the secret information held one-to-one with the transmission side device, and outputting the decryption key included in the decrypted license information Processing means,
Decryption output means for decrypting the encrypted content with the decryption key output by the license information processing means and outputting the content;
A license information receiving program that is made to function as: The license information transmission method according to claim 3 receives the multiplexed content transmitted from the transmission-side device, and separates the encrypted license information and the encrypted content multiplexed in the multiplexed content. A license information receiving method for decrypting,
A receiving and separating step of receiving the multiplexed content and separating the encrypted license information and the encrypted content;
The license for decrypting the encrypted license information separated in the reception separation step with the secret information held one-to-one with the device on the transmission side, and outputting the decryption key included in the decrypted license information An information processing step;
A decryption output step of decrypting the encrypted content with the decryption key output in the license information processing step and outputting the content;
Including a license information receiving method.

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