JP2003179591A - Smart card, reproduction/management device, method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent distributed contents from being illegally copied even by high-level illegal copy techniques. <P>SOLUTION: By using a reproduction/management device 20 and an IC card 10 having a common authentic key Ka, a random number r2 generated by the reproduction/management device 20 is exactly distributed to the IC card 20 and in the reproduction/management device 20, an enciphered contents key E (r2, Kc) received from the IC card 10 is deciphered by the random number r2 so that contents data C can be reproduced by the obtained contents key Kc. Namely, since the IC card 10 is required for reproducing the contents, the illegal copy is made extremely difficult. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a smart card, a reproduction / management apparatus, a method and a program for preventing illegal copying of contents.

[0002]

2. Description of the Related Art At present, a content distribution business for distributing digital contents (hereinafter referred to as contents) of music and / or video is prosperous due to improvement of performance of PC (personal computer; hereinafter referred to as personal computer) and spread of network environment. Has been done in.

In this type of content distribution business, since the content has the property of being easily copied,
It is necessary for the content management system under the distribution business to be equipped with technology for preventing illegal copying of content.

However, such a content management system does not have a high-level illegal copy prevention technology because it is difficult to construct a high-security illegal copy prevention technology for a personal computer having an open architecture.

[0005]

As described above,
Conventional content management systems do not have sophisticated illicit copy protection technology. For this reason, if a malicious third party uses a high-level illegal copy technique, the delivered content is illegally copied.

The present invention has been made in consideration of the above circumstances, and provides a smart card, a reproducing / managing apparatus, a method and a program capable of preventing illegal copying of distributed contents even with a high-level illegal copying technique. The purpose is to provide.

[0007]

A first invention is a random number r2.
A reproducing / managing apparatus for decrypting the encrypted content E (Kc, C) and reproducing the content data C based on the content key Kc obtained by decrypting the encrypted content key E (r2, Kc). On the other hand, a smart card that is detachably held to provide the encrypted content key E (r2, Kc), and is activated based on a reproduction command transmitted from the reproduction / management apparatus, and generates a random number. r1
And a random number r1 generated by the random number generation means are encrypted with an authentication key Ka common to the reproduction / management apparatus, and the obtained encrypted random number E (Ka,
r1) is transmitted to the reproduction / management apparatus, and the encrypted exclusive OR value E received from the reproduction / management apparatus in response to the transmission by the first encryption means.
(Ka, r1 (+) r2) is decrypted by the authentication key Ka to obtain a decryption result (r1 (+) r2), a decryption result by the first decryption unit, and the random number generation unit. The exclusive OR calculation means for calculating the exclusive OR with the random number r1 generated by the above and the input encrypted content key E (Ki, Kc) by the own card unique key Ki. Content key K obtained by decryption
The second decryption means for transmitting c and the content key Kc obtained by the second decryption means are encrypted by the calculation result r2 obtained by the exclusive OR calculation means, and the obtained encrypted content key is obtained. A second encryption means for transmitting E (r2, Kc) to the playback / management apparatus, and a smart card.

A second invention is a reproducing / managing apparatus for removably holding a smart card, decrypting the encrypted content E (Kc, C) based on the content key Kc, and reproducing the content data C. When activated on the basis of a reproduction command for reproduction, the random number generating means for generating a random number r2 and the encrypted random number E (Ka, r1) transmitted from the smart card are used as the smart card. A first decryption unit that obtains a random number r1 by decrypting with a common authentication key Ka, and an exclusive OR of the random number r1 obtained by the first decryption unit and the random number r2 generated by the random number generation unit are calculated. Then, the exclusive OR calculation means for obtaining the calculation result (r1 (+) r2) and the calculation result by the exclusive OR calculation means are encrypted by the authentication key Ka, and the obtained encrypted exclusive OR value E is obtained. (Ka, r (+) r2) is transmitted to the smart card, and the encrypted content key E (r2, Kc) received from the smart card is generated by the random number generation means in response to the transmission by the encryption means. And a second decryption unit that obtains the content key Kc by decrypting the generated random number r2.

As described above, by using the reproducing / managing apparatus having the common authentication key Ka and the smart card,
The random number r2 generated by the playback / management device is accurately distributed to the smart card, and the playback / management device decrypts the encrypted content key E (r2, Kc) received from the smart card with the random number r2 to obtain the content. The content data C can be reproduced with the key Kc.

That is, since a smart card is required when reproducing the contents, even if the advanced illegal copying technique is used, the illegal copying of the distributed contents can be prevented.

Although each of the above inventions is expressed in the category of "apparatus", the invention is not limited to this and may be expressed in another category or name such as "method", "program" or "system".

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. In the following description, E
The notation (K, M) represents the data E obtained by encrypting the message M with the key K. In addition, the present embodiment uses a common key cryptosystem in which a common key is used for encryption and decryption.

FIG. 1 is a schematic diagram showing the structure of a content management system including a smart card and a reproduction / management apparatus according to an embodiment of the present invention. This system includes an IC card 10 as a smart card, a reproduction / management device 20 using a personal computer, and a hard disk 30. The IC card 10 and / or the reproduction / management device 20 are
It can be realized as either a hardware configuration and / or a software configuration, but in the case of a software configuration, it can be realized by previously installing a program from a storage medium or a network. The reproducing / managing apparatus 20 and the hard disk 30 may be integrated or separate, and the reproducing / managing apparatus 20 may be a mobile phone and the hard disk 30 may be a portable storage medium. In this case, the IC card 10 is used. SIM (subscriber
identity module) card.

Here, the IC card 10 is detachably attached to the reproduction / management apparatus 20, and the content list L, the control unit 11, the random number generation unit 12, the encryption unit 13, and the decryption unit 14 are included.
And an XOR unit 15.

The content list L is readable / writable by the control unit 11 and written in the tamper resistant area.
It includes an IC card unique key Ki for each C card 10, a device exclusion information update key Kr for updating Ki, an authentication key Ka for authenticating with the reproduction / management apparatus 20, and each content ID. The authentication key Ka includes key information and an expiration date of the authentication key Ka.

The control unit 11 confirms the expiration date of the authentication key Ka, and processes according to each command based on a reproduction command, an addition command, a deletion command or a key update command transmitted from the reproduction / management apparatus 20. For executing the process, specifically, the random number generation unit 12, the encryption unit 13, and the decryption unit so that the process is executed in the procedure shown in FIGS. 2 to 5 while referring to the content list L. 14 has the function of controlling.

The random number generator 12 is activated by the controller 11 to generate a random number r1, and the obtained random number r1 is encrypted by the encryption unit 13.
And the function of sending to the XOR unit 15.

The encryption unit 13 encrypts an arbitrary message M input based on the key K sent from the control unit 11, the random number generation unit 12 or the decryption unit 14, and obtains any encrypted data obtained. It has a function of outputting E (K, M) to the reproduction / management apparatus 20 or the hard disk 30.

The decryption unit 14 receives arbitrary encrypted data E based on the key K sent from the control unit 11.
It has a function of decrypting (K, M) and outputting the obtained plaintext message M to the encryption unit 13 or the XOR unit 15.

The XOR unit 15 obtains the exclusive OR (XOR) of the random number r1 sent from the random number generation unit 12 and the decoding result (r1 (+) r2) sent from the decoding unit 14,
It has a function of sending the obtained XOR value r2 to the encryption unit.

The reproducing / managing apparatus 20 holds the IC card 10 in a detachable manner, is connected to the hard disk 30, and has a control unit 21, a decryption unit 22, a random number generation unit 23, and an XOR unit 24.
And an encryption unit 25.

The control unit 21 sends a content reproduction command, an addition command, a deletion command, or a key update command to the IC card 10 based on the operation of the operator and the processing based on the content of each command. And specifically has a function of controlling the decryption unit 22, the random number generation unit 23, and the encryption unit 25 so that the process is executed in the procedure shown in FIGS.

The decryption unit 22 decrypts the arbitrary encrypted data E (K, M) that is input based on the key K sent from the control unit 21 or its own decryption unit 22, and the obtained plaintext is obtained. It has a function of outputting the message M to its own decryption unit 22, XOR unit 24, or encryption unit 25.

The random number generation unit 23 has a function of being activated by the control unit 21 to generate a random number r2 and sending the obtained random number r2 to the decryption unit 22 and the XOR unit 24.

The XOR section 24 obtains the exclusive OR (XOR) of the random number r2 sent from the random number generation section 23 and the decoding result r1 sent from the decoding section 22, and the obtained XO
It has a function of transmitting the R value (r1 (+) r2) to the encryption unit 25.

The encryption unit 25 encrypts an arbitrary message M input based on the key K sent from the control unit 21, the random number generation unit 23 or the decryption unit 22, and obtains any encrypted data obtained. It has a function of outputting E (K, M) to the IC card 10 or the hard disk 30.

The hard disk (HDD) 30 is a storage device that can be read / written by the IC card 10 and the reproduction / management device 20, and is not limited to a hard disk, and can be any storage device or storage medium (eg, smart media). You may change it. Further, the storage medium is not limited to one having only a memory function, and may be changed to a storage medium having a calculation function.

Next, the operation of the content management system configured as above will be described in the order of "content reproduction", "content addition", "content deletion" and "illegal device exclusion" with reference to FIGS. explain.

For convenience of explanation in chronological order, the same functional units having the same numerals will be denoted by different alphabets and the processing contents will be distinguished. For example, regarding the decryption unit 22, a and b are added to represent the decryption unit 22a and the decryption unit 22b, and the processing content will be described separately. Note that this description is based on the assumption that the same functional units having the same numbers are executed by the same circuit or the like, but the present invention is not limited to this, and the same functional units having the same numbers that are distinguished by each alphabet are created separately. It goes without saying that it is okay. Further, although the input / output of data is directly performed between the functional units, the bus and / or the memory (not shown) may be used in practice.

(Content reproduction: FIG. 2) Content C1
When reproducing the content, in the reproduction / management apparatus 20, as shown in FIG. 2, the control unit 21 issues the reproduction instruction of the content C1 to the IC.
At the same time as transmitting to the card 10, the random number r2 is distributed to the IC card 10.

On the other hand, in the IC card 10, the control section 11 similarly reproduces and manages the reproduction / management apparatus 20 based on the reproduction instruction.
And the random number r2 is received.

Specifically, in the IC card 10, the control unit 11 activates the random number generation unit 12, checks the expiration date of the authentication key Ka, and sends the authentication key Ka to the encryption unit 13 within the expiration date. To do. If the expiration date of the authentication key Ka is out of date, the processing is stopped.

The random number generator 12 is activated to generate a random number r1, and the random number r1 is encrypted by an encryption unit 13 and an XOR unit 15.
Send to.

The encryption unit 13 uses the random number r1 as the authentication key K.
The encrypted random number E (Ka, r
1) is transmitted to the reproduction / management apparatus 20.

In the reproducing / managing apparatus 20, the control unit 21 sends the device key Kd1 of the own apparatus 20 after sending the above-mentioned reproducing command.
Is sent to the decryption unit 22a, and the encrypted authentication key E (Kd1, Ka) of the own device 20 is read from the hard disk 30 and sent to the decryption unit 22a.

The decryption unit 22a uses the encrypted authentication key E (K
(d1, Ka) is decrypted by the device key Kd1, and the obtained authentication key Ka is sent to the decryption unit 22b and the encryption unit 25.

Here, the decryption unit 22b uses the authentication key Ka.
Based on the encrypted random number E (K
a, r1) is decrypted, and the random number r1 obtained is decoded by the XOR unit 24
Send to.

On the other hand, the random number generator 23 is activated by the controller 21 to generate a random number r2, and the random number r2 is used by the XOR unit 2
4 and the decoding unit 22c.

The XOR section 24 uses these two random numbers r1,
The exclusive OR of r2 is calculated and the obtained XOR value (r1
(+) r2) is sent to the encryption unit 25.

The encryption unit 25 encrypts the XOR value (r1 (+) r2) based on the authentication key Ka from the decryption unit 22a, and obtains the encrypted XOR value E (Ka, r1 (+) r2). )
Is transmitted to the IC card 10.

This completes the process of distributing the random number r2 on the reproduction / management device 20 side.

In the IC card 10, the decryption unit 14a uses the authentication key Ka to generate the encrypted XOR value E (Ka, rl (+) r.
2) is decrypted, and the decryption result (r1 (+) r2) is decrypted by the XOR unit 1
Send to 5.

The XOR unit 15 outputs the decoding result (r1 (+)
The exclusive OR of r2) and the random number r1 generated by the random number generator 12 is calculated, and the obtained XOR value r2 is sent to the encryption unit 13b.

As a result, the random number r on the IC card 10 side
The receiving process of 2 is completed.

Next, the control unit 11 of the IC card 10 makes the I
The C card unique key Ki is sent to the decryption unit 14b, and
The encrypted content key E (Ki, Kc1) of the own card 10 read from the hard disk 30 is sent to the decryption unit 14b.

The decryption unit 14b decrypts the encrypted content key E (Ki, Kc1) based on the IC card unique key Ki, and sends the obtained content key Kc1 to the encryption unit 13b.

The encryption unit 13b uses the X from the XOR unit 15
The content key Kc1 is encrypted based on the OR value r2, and the obtained encrypted content key E (r2, Kc1) is transmitted to the reproduction / management apparatus 20.

In the reproducing / managing apparatus 20, the decoding section 22c is
Based on the random number r2 from the random number generation unit 23, the encrypted content key E (r2, Kc1) from the IC card 10 is decrypted, and the obtained content key Kc1 is sent to the decryption unit 22d.

The decryption unit 22d uses the content key to encrypt the encrypted content E (Kc
1, C1) to reproduce the content C1. This completes the reproduction process of the content C1.

(Addition of content: FIG. 3) Content C2
In the case of adding a content, in the reproduction / management apparatus 20, the control unit 21 issues an instruction to add the content C2 as shown in FIG.
While transmitting to the C card 10, the random number r2
The distribution process of is executed.

The control unit 11 of the IC card 10 adds the ID of the content C2 to the content list L based on this addition instruction, and then executes the receiving process of the random number r2 as described above.

Next, it is assumed that the distribution process and the reception process of the random number r2 are completed as described above.

On the reproduction / management apparatus 20 side, the encryption unit 25
The a encrypts the content key Kc2 of the content C2 based on the random number r2 from the random number generator 23, and uses the obtained encrypted content key E (r2, Kc2) as the IC card 1
Send to 0.

Further, the encryption unit 25b uses the content key K
The content C2 is encrypted based on c2, and the obtained encrypted content E (Kc2, C2) is additionally written to the hard disk 30 and written.

On the other hand, in the IC card, the decryption unit 14c
Based on the XOR value r2 from the XOR unit 15, the encrypted content key E (r2, Kc from the playback / management apparatus 20.
2) is decrypted, and the obtained content key Kc2 is sent to the encryption unit 13c.

The encryption unit 13c encrypts the content key Kc2 based on the IC card unique key Ki of the own card received from the control unit 11, and obtains the encrypted content key E obtained.
(Ki, Kc2) is added to the hard disk 30 and written.

This completes the process of adding the content C2.

(Delete content: FIG. 4) Content C1
When deleting the, the IC card 10 controls the control unit 11 based on the deletion instruction of the content C1 as shown in FIG.
The ID1 of the content C1 is deleted from the content list L.

Next, the control section 11 controls the content list L.
All content IDs other than the deleted ID1 in
The encrypted content key E (Ki, Kcj) of the content j corresponding to (j ≠ 1) is read from the hard disk 30 and sent to the decryption unit 14b.

The control unit 11 also activates the random number generation unit 12 and sends the IC card unique key Ki of the own card 10 to the decryption unit 14b.

The decryption unit 14b decrypts the encrypted content key E (Ki, Kcj) based on the IC card unique key Ki, and sends the obtained content key Kcj to the encryption unit 13c. Also, the random number generator 12 is activated to generate the random number K.
i ′ is generated and this random number Ki ′ is sent to the control unit 11 and the encryption unit 13c.

The encryption unit 13c encrypts the content key Kcj on the basis of this random number Ki ', and the obtained encrypted content key E (Ki', Kcj) is stored on the hard disk 3.
Update to 0.

Similarly, the encrypted content key E (Ki, Kcj) of the content j corresponding to all the content IDj (j ≠ 1) other than the deleted ID1 is set to E (Ki ',
Kcj).

All encrypted content keys E (Ki ', K
After the completion of updating cj), the control unit 11 updates the IC card unique key Ki in the content list L to Ki ′, and completes the deletion process.

As a result, even if the encrypted content key E (Ki, Kcj) is to be decrypted from the storage medium that backs up the hard disk 30 before the deletion process, the decryption can be prevented.

(Exclusion of Unauthorized Device: FIG. 5) When excluding an unauthorized device (unauthorized reproducing / managing device), the IC card 10 sends an instruction to update the authentication key Ka to the control unit as shown in FIG. 11 and the new encrypted authentication key E (Kr, K
It is assumed that a ′) is input to the decoding unit.

The input path is (1) distributor → Internet → user's personal computer → playback / management apparatus 20.
→ The IC card 10 may be used, or (2) a terminal such as a convenience store → The IC card 10 may be used.

The control unit 11 decrypts the device exclusion information update key Kr in the content list L with the decryption unit 14d according to the update command.
Send to.

The decryption unit 12 decrypts the encrypted authentication key E (Kr, Ka ') based on the device exclusion information update key Kr,
The obtained authentication key Ka ′ is sent to the control unit 11.

The control section 11 updates the authentication key Ka of the content list L with a new authentication key Ka '.

On the other hand, the hard disk 30 has new encrypted authentication keys E (Kd1, Ka '), E (Kd2, Ka'), E (K) distributed from the distributor via the Internet.
, d3, Ka '), ... Are written via a personal computer (not shown) or the reproduction / management apparatus 20. The encryption authentication key E
(Kr, Ka ') IC card 10 with digital signature
In the case of inputting into, the IC card (smart card) 10 described above is added with the function of verifying the digital signature.

As described above, according to this embodiment, the reproduction / management apparatus 20 and the IC card 1 having the common authentication key Ka.
By using 0 and 0, the random number r2 generated by the reproduction / management apparatus 20 is accurately distributed to the IC card 10, and the reproduction management apparatus 20 uses the encrypted content key E (r2, Kc) received from the IC card 10. Decrypt with random number r2,
The content data C can be reproduced by using the obtained content key Kc.

That is, when reproducing the content, I
Since the C card 10 is required, it is possible to prevent the illegal distribution of the distributed content even with the advanced illegal copy technology.

Further, the IC card 10 and the reproduction / management device 2
Since the encrypted data is linked to 0 by exclusive OR (XOR), mutual authentication between both devices 10 and 20 can be performed at high speed.

In addition, when adding the content, the random number r2 is similarly distributed to the IC card 10 so that the IC
In the card 10, the encrypted content key E (r2, Kc) received from the reproduction / management apparatus is re-encrypted with the card unique key Ki, and the obtained encrypted content key E (Ki, Kc
c) can be written in the hard disk 30. That is, when the content is added, similarly, the IC card 10 is required, so that the illegal copy of the content can be prevented.

When deleting the content, the ID of the content to be deleted is deleted from the content list. After that, the IC card 10 uses the new card unique key K
i ', and the remaining encrypted content key E (K
i, Kcj) is re-encrypted and a new encrypted content key E (Ki ′, Kcj) is written in the hard disk 30. As a result, the deletion can be performed smoothly, and it becomes impossible to back up the encrypted content key E (Ki, Kcj) before the deletion and illegally reproduce it.

When excluding illegal devices, the IC
Since the card 10 uses the new authentication key Ka ′ obtained by decryption with the device exclusion information update key Kr,
An unauthorized device having the old authentication key Ka can be excluded.

That is, even when the content is deleted or the unauthorized device is removed, the IC card 10 is used to update the card unique key Ki and the authentication key Ka necessary for reproducing the content. It is possible to reliably prevent illegal copying.

The method described in each of the above embodiments is
As a program that can be executed by a computer, a magnetic disk (floppy (registered trademark) disk,
Hard disk, etc., Optical disk (CD-ROM, D
It can be stored in a storage medium such as a VD), a magneto-optical disk (MO), a semiconductor memory or the like and distributed.

The storage medium may have any storage format as long as it can store the program and is readable by the computer.

An OS (operating system) running on the computer based on the instructions of the program installed in the computer from the storage medium,
MW such as database management software and network software
(Middleware) or the like may execute a part of each processing for realizing the present embodiment.

Further, the storage medium in the present invention is not limited to a medium independent of the computer, but includes a storage medium in which a program transmitted via a LAN, the Internet or the like is downloaded and stored or temporarily stored.

Further, the number of storage media is not limited to one, and the case in which the processing in this embodiment is executed from a plurality of media is also included in the storage media in the present invention, and the medium configuration may be any configuration.

The computer according to the present invention executes each processing in the present embodiment based on the program stored in the storage medium, and a device such as a personal computer or a plurality of devices are connected to the network. It may have any configuration such as an established system.

The computer in the present invention means
Not only a personal computer but also an arithmetic processing unit, a microcomputer, and the like included in an information processing device, which collectively refer to a device and a device that can realize the functions of the present invention by a program.

The invention of the present application is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention at the stage of implementation. In addition, the respective embodiments may be implemented by being combined appropriately as far as possible, in which case the combined effects can be obtained. Further, the above-described embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent requirements. For example, when the invention is extracted by omitting some of the constituent elements shown in the embodiment, when omitting the extracted invention, the omitted portions are appropriately supplemented by well-known and common techniques. It is something that will be done.

Besides, the present invention can be variously modified and implemented without departing from the gist thereof.

[0088]

As described above, according to the present invention, it is possible to prevent the illegal distribution of the distributed contents even with the advanced illegal copy technology.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a content management system including a smart card and a playback / management device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining a content reproducing operation in the same embodiment.

FIG. 3 is a schematic diagram for explaining a content addition operation in the same embodiment.

FIG. 4 is a schematic diagram for explaining a content deletion operation in the same embodiment.

FIG. 5 is a schematic diagram for explaining an operation of excluding an unauthorized device according to the first embodiment.

[Description of Codes] IC Cards 11, 21 ... Control Units 12, 23 ... Random Number Generation Units 13, 13a to 13c, 25, 25a to 25b ... Encryption Units 14, 14a to 14c, 22, 22a to 22d ... Decryption Unit 15 , 24 ... XOR unit 20 ... Reproduction / management apparatus L ... Content list Ki, Ki '... Card unique key Ka ... Authentication key Kd1, Kd2 ... Device key Kr ... Device exclusion information update key Kc1, Kc2, Kcj ... Content key C1, C2 ... contents r1, r2 ... random numbers

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5B035 AA13 BB09 CA11 CA29                 5D044 BC01 CC05 CC08 GK17 HL11                 5J104 AA08 AA13 JA04 LA02 NA35                       PA07 PA14

Claims (11)

[Claims] 1. A content key E encrypted with a random number r2.
Based on the content key Kc obtained by decrypting (r2, Kc), it is detachably held by the reproducing / managing apparatus for decrypting the encrypted content E (Kc, C) and reproducing the content data C. The encrypted content key E
A smart card for providing (r2, Kc), comprising: a random number generation unit that generates a random number r1 when activated based on a reproduction command transmitted from the reproduction / management apparatus; A first encryption means for encrypting the generated random number r1 with an authentication key Ka common to the reproduction / management apparatus, and transmitting the obtained encrypted random number E (Ka, r1) to the reproduction / management apparatus. , The reproduction / playback in response to the transmission by the first encryption means.
The encrypted exclusive OR value E (Ka,
r1 (+) r2) is decrypted by the authentication key Ka to obtain a decryption result (r1 (+) r2), a decryption result by the first decryption unit, and a random number generator. The exclusive OR with the random number r1
An exclusive OR calculating means for obtaining the calculation result r2, and a second decryption for decrypting the input encrypted content key E (Ki, Kc) with its own card unique key Ki and sending out the obtained content key Kc. And the content key Kc obtained by the second decryption means by the calculation result r2 obtained by the exclusive OR calculation means, and the obtained encrypted content key E (r2, Kc)
A second encryption means for transmitting the data to the reproduction / management device, and a smart card. 2. The smart card according to claim 1, wherein all the I of the card unique key Ki, the authentication key Ka, the authentication key update key Kr, and the reproducible content data C.
D is a smart card characterized by being stored in a storage area that cannot be read from the outside of the smart card body. 3. The smart card according to claim 2, wherein the new encrypted content key E (r2, Kc ′) received from the playback / management apparatus is obtained by the exclusive OR calculation means. Third decryption means for decrypting with r2 and transmitting the obtained new content key Kc ′, and encrypting the new content key Kc ′ transmitted from the third decrypting means with its own card unique key Ki. , Third encryption means for outputting the obtained new encrypted content key E (Ki, Kc ′), and the new content key Kc ′ and the new encrypted content E (Kc ′, C ′). When an additional command for adding is received from the reproduction / management apparatus, the ID of the content data C ′ is added to the storage area, and instead of using the second decryption means and the second encryption means. , The third Decoding means and said third smart cards to the additional control means, comprising the controlling to use encryption means. 4. The smart card according to claim 2 or 3, wherein when a delete command for deleting the content data C is received from the reproduction / management apparatus, the ID of the content data C to be deleted is stored in the storage card. Deletion control means for deleting from the area and individually sending the card unique key Ki and unique key update command; and when the deletion by the deletion control means is completed, read from the outside in correspondence with the remaining IDs in the storage area. The encrypted content key E (Ki, Kcj) to be decrypted based on the card unique key Ki sent by the deletion control means,
Fourth decryption means for obtaining the content key Kcj, unique key generation means for generating a new card unique key Ki ′ based on the unique key update command sent by the deletion control means, and the fourth decryption means Content key Kc obtained by
And a fourth encryption means for encrypting the new encrypted content key E (Ki ', Kcj) obtained by encrypting the new card unique key Ki' generated by the unique key updating means. , A unique key updating means for updating the card unique key Ki in the storage area to the new card unique key Ki ′ generated by the unique key generating means. 5. The smart card according to claim 2, wherein when an authentication key update command for updating the authentication key Ka is input, the authentication key update is performed from the storage area. An update key reading means for reading the encryption key Kr and a new encrypted authentication key E (Kr, K) input from the outside.
a ') is decrypted based on the authentication key updating key Kr read by the updating key reading means, and a new authentication key K is obtained.
a fifth decryption means for obtaining a ′, and an authentication key update means for updating the authentication key Ka in the storage area to the new authentication key Ka ′ decrypted by the fifth decryption means. Characteristic smart card. 6. A smart card is detachably held, and encrypted content E (K
(c, C) for reproducing the content data C by decoding the random number r when activated based on a reproduction command for reproduction.
2, a random number generation means for generating 2, and the encrypted random number E (K
a, r1) is the authentication key Ka common to the smart card.
A first decryption unit that obtains a random number r1 by decrypting with, and an exclusive OR of the random number r1 obtained by the first decryption unit and the random number r2 produced by the random number producing unit,
The exclusive OR calculation means for obtaining the calculation result (r1 (+) r2) and the calculation result by the exclusive OR calculation means are the authentication key Ka.
The encrypted exclusive OR value E (K
a, r1 (+) r2) to the smart card, and the encrypted content key E (r2, Kc) received from the smart card in response to the transmission by the encryption means to generate the random number. And a second decryption unit that obtains the content key Kc by decrypting the random number r2 generated by the unit. 7. The reproducing / managing apparatus according to claim 6, wherein the content key Kc ′ to be added is encrypted by the random number r2 generated by the random number generating means, and a new encrypted content key E ( r2, Kc ') for transmitting to the smart card, and content data C'to be added is encrypted by the content key Kc' to be added, and a new encrypted content E ( Kc ', C') outputs a third encryption means, and an additional command for adding the new content key Kc 'and the new encrypted content E (Kc', C ') is input. A reproducing / managing apparatus comprising: an additional control unit that controls the second and third encryption units to be used instead of the second decryption unit. 8. A content key E encrypted with a random number r2.
Based on the content key Kc obtained by decrypting (r2, Kc), it is detachably held by the reproducing / managing apparatus for decrypting the encrypted content E (Kc, C) and reproducing the content data C. The encrypted content key E
A method of providing a content key used for a smart card for providing (r2, Kc), wherein a random number r1 is generated in the smart card when activated based on a reproduction command transmitted from the reproduction / management apparatus. And a random number r1 generated in the random number generating step is encrypted by an authentication key Ka common to the reproducing / managing apparatus, and the encrypted random number E (Ka, r1) obtained is reproduced. A first encryption step for transmitting to the management device, and the reproduction according to the transmission by the first encryption step.
The encrypted exclusive OR value E (Ka,
r1 (+) r2) is decrypted by the authentication key Ka to obtain a decryption result (r1 (+) r2), and a decryption result by the first decryption step and the random number generation step are generated. The exclusive OR with the random number r1
An exclusive OR calculation step of obtaining the calculation result r2, and a second decryption in which the input encrypted content key E (Ki, Kc) is decrypted by the card unique key Ki of its own, and the obtained content key Kc is transmitted. Step, and the content key Kc obtained in the second decryption step is encrypted by the calculation result r2 obtained in the exclusive OR calculation step, and the obtained encrypted content key E (r2, Kc)
A second encryption step of transmitting the content key to the reproduction / management apparatus, and the content key providing method. 9. A smart card is detachably held, and encrypted content E (K
(c, C) for reproducing the content data C by decoding the content data C, wherein the content reproduction method is started in the reproduction / management apparatus based on a reproduction instruction for reproduction. And random number r
2, a random number generation step of generating 2, and the encrypted random number E (K
a, r1) is the authentication key Ka common to the smart card.
A first decryption step for obtaining a random number r1 by performing a decryption according to, and an exclusive OR of the random number r1 obtained in the first decryption step and the random number r2 produced in the random number producing step,
The exclusive OR calculation step of obtaining the calculation result (r1 (+) r2) and the calculation result of the exclusive OR calculation step are used as the authentication key Ka.
The encrypted exclusive OR value E (K
a, r1 (+) r2) is transmitted to the smart card, and the encrypted content key E (r2, Kc) received from the smart card is generated in the random number in response to the transmission by the encryption step. And a second decryption step of obtaining the content key Kc by decrypting the random number r2 generated in the step. 10. A content key E encrypted with a random number r2.
Based on the content key Kc obtained by decrypting (r2, Kc), it is detachably held by the reproducing / managing apparatus for decrypting the encrypted content E (Kc, C) and reproducing the content data C. The encrypted content key E
A program used for a smart card for providing (r2, Kc), which generates a random number r1 when the computer of the smart card is activated based on a reproduction command transmitted from the reproduction / management apparatus. Random number generating means for encrypting the random number r1 generated by the random number generating means with an authentication key Ka common to the reproducing / managing apparatus, and the encrypted random number E (Ka, r1) obtained is the reproducing / managing apparatus. A first encryption means for transmitting to the playback device, and the reproduction / playback in response to the transmission by the first encryption means.
The encrypted exclusive OR value E (Ka,
r1 (+) r2) is decrypted by the authentication key Ka to obtain a decryption result (r1 (+) r2), the decryption result by the first decryption unit and the random number generation unit. Calculate exclusive OR with random number r1,
An exclusive OR calculating means for obtaining the calculation result r2, and a second decryption for decrypting the input encrypted content key E (Ki, Kc) with its own card unique key Ki and sending out the obtained content key Kc. Means for encrypting the content key Kc obtained by the second decryption means with the calculation result r2 obtained by the exclusive OR calculation means, and the obtained encrypted content key E (r2, Kc)
A program for functioning as a second encryption means for transmitting to the reproduction / management apparatus. 11. A smart card is detachably held,
Based on the content key Kc, the encrypted content E (K
(c, C) is a program used in a reproducing / managing apparatus for reproducing the content data C by decoding the computer of the reproducing / managing apparatus based on a reproducing command for reproducing. , Random number r
Random number generation means for generating 2, encrypted random number E (K
a, r1) is the authentication key Ka common to the smart card.
A first decryption unit that obtains a random number r1 by calculating the exclusive OR of the random number r1 obtained by the first decryption unit and the random number r2 generated by the random number generation unit,
Exclusive OR calculation means for obtaining the calculation result (r1 (+) r2), and the calculation result by the exclusive OR calculation means for the authentication key Ka
The encrypted exclusive OR value E (K
a, r1 (+) r2) is transmitted to the smart card, and the encrypted content key E (r2, Kc) received from the smart card in response to the transmission by the encryption means is generated by the random number generation means. A program for functioning as a second decryption unit that obtains the content key Kc by decrypting the random number r2 generated by.