JP2005071029A - Rewritable ic card - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rewritable IC card which is high in efficiency and safety in the mutual authentication of communication through a disclosed network between an IC card and a service providing institution. <P>SOLUTION: In this rewritable IC card, the IC card 100 is characterized by personally setting an access frequency holding part 302 and an access arithmetic value holding part 303 at the time of registration, and using the access frequency calculated by using the value of the access arithmetic value holding part 303 each time access is performed through a network 101 to a media distribution institution 102 for authentication between the IC card 100 and the medial distribution facility 102, and alternately using and updating authentication keys held in authentication key holding parts A301 and B302. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rewritable IC card, and in particular, whether communication is performed with a legitimate partner when communicating between a personal IC card and a content distribution organization via a network that is not a dedicated line. The present invention relates to an improvement in technology used for mutual authentication.

  First, mutual authentication between an IC card and a media distribution organization that distributes content via a network, which is used for this kind of conventional application, will be described.

  This mutual authentication prevents spoofing and the like by, for example, authenticating whether or not a media distribution organization that distributes paid content and a network terminal used by the authorized subscriber are the original communication partners. It is used to do.

  FIG. 4 is a diagram showing a configuration of mutual authentication between a conventional IC card and a media distribution organization. FIG. 4 shows a system configuration similar to the IC card processing method disclosed in Patent Document 1, but an example of the internal block configuration of the IC card is also shown.

  In FIG. 4, 100 is an IC card, 101 is a public network, that is, a network that is not a dedicated line, and this corresponds to the Internet. 102 is a media distribution organization (service distribution organization) that distributes content via the network 101, and 103 is a unique ID (ID for identifying each IC card) that is set when the IC card 100 is registered in the media distribution organization 102. IDification), 104 is set when registering the IC card 100 in the media distribution organization 102, and is an authentication key holding unit required when authenticating the proper owner of the IC card using encryption, and 105 is the media distribution organization 102 Authentication password holding unit set when registering the IC card 100, 106 a random number generator for generating a random number, 107 a CPU for controlling the IC card 100, 108 for media distribution via the network 101 by the IC card 100 A network terminal 109 for communicating with the institution 102, I / F (Interface) for communicating with the network terminal 108, 110 is the same registration ID as the unique ID 103 set when the IC card 100 is registered, and 111 is that of the authentication key holding unit 104 set when the IC card 100 is registered The same registration key 112 is the same registration password as that of the authentication password holding unit 105 set when the IC card 100 is registered.

  The update of the mutual authentication key in the configuration of FIG. 4 will be described using the flowchart of FIG.

Here, in the following data encryption or decryption, it is assumed as follows.
Function name = E / D (A, B)

  In the above equation, E / D = E: encryption, D: decryption, A is a key for encryption or decryption, and B is plaintext or ciphertext.

For example, to generate plaintext B by encrypting plaintext B with key A,
C = E (A, B)
. On the other hand, decoding is B = D (A, C)
.

  In addition, the authorized owner of the IC card, that is, the authorized subscriber of the media distribution institution, notifies the media distribution institution of the desired authentication password in a manner capable of keeping secret when subscribing to the distribution service. As a result, the media distribution organization stores this authentication password as a registration password, and this authentication password is set in the authentication password holding unit 105 when the IC card 100 is issued and is delivered to the subscriber. The authentication key holding unit 104 of the IC card 100 is set with the same authentication key as the registration key set in the media distribution organization 102 when the IC card is issued.

  Furthermore, the unique ID 103 of the IC card 100 is assigned different data for each individual card when the IC card is manufactured.

  First, in order to perform mutual authentication with the media distribution institution 108, the IC card 100 is connected to the network terminal 108 (such as being inserted into a slot of the terminal 108), so that the IC card is connected to the network terminal 108 through the I / F 109. It communicates with the media distribution organization 102 via 101.

  As a mutual authentication key update method in the IC card 100 and the media distribution institution 102, the IC card 100 generates a random number of a sequence of a predetermined length by the random number generator 106 in step 200, and holds this as R0. Next, in step 201, the authentication password of the authentication password holding unit 105 and the random number R0 are encrypted under the control of the CPU 107 using the authentication key of the authentication key holding unit 104 to obtain a ciphertext e0. A unique ID 103 is transmitted to the media distribution organization 102 together with the ciphertext e0.

  The media distribution institution 102 decrypts the ciphertext e0 in step 202 with the registration key 111 registered on the institution 102 side to obtain plaintext d0, and then in step 203 the authentication password included in the plaintext d0 and the institution 102 In the case of non-coincidence (no), the communication is terminated as authentication NG, and in the case of coincidence (yes), authentication OK and then in step 204, the plaintext d0 includes the plaintext d0. The random number R0 is encrypted with the registration key 111 to create a ciphertext e1, and a new authentication key is generated with an authentication key generation algorithm or the like, and this is encrypted with the registration key 111 to generate a ciphertext e2, and the ciphertext e1 and e2 are transmitted to the IC card 100. After the transmission, the new authentication key is set as the registration key 111 in step 205.

  The IC card 100 decrypts the ciphertext e1 with the key of the authentication key holding unit 104 into the plaintext d1 at step 206, and then compares the plaintext d1 with the random number R0 held at the time of random number generation at step 207. If they do not match (no), the communication ends as authentication NG. If they match, authentication OK is performed, and in step 208, the ciphertext e2 is decrypted with the key of the authentication key holding unit 104 to generate plaintext d2, and in step 209 The key for mutual authentication is updated by registering the plaintext d2 in the authentication key holding unit 104 as a new key.

  If the mutual authentication is OK, the media distribution organization 102 starts distributing content to the network that has performed the mutual authentication.

Thus, according to the mutual authentication method using the conventional IC card, the encrypted data including the random number generated on the IC card side is decrypted on the media distribution institution side, and the decrypted random number is encrypted and the IC card side Since the other party is authenticated based on whether or not the random number decoded on the IC card side matches the original random number, the media distribution organization connected to the public network and the network terminal You can check whether you are communicating with the other party.
Japanese Patent Laid-Open No. 10-222468 (page 3-4, FIGS. 1 to 9)

  However, in the above-described conventional method, when there is one authentication key, the security is lowered because the same key is continuously used when receiving services other than the key update, and even if there are a plurality of authentication keys, If these are used even once on a public network, the risk of decryption increases when the authentication key is updated, and there is a problem in terms of safety.

  The present invention has been made to solve the above-described conventional problems, and is an efficient and safer rewritable type for mutual authentication of communication via an IC card and a public network in a service provider. An object is to provide an IC card.

  The rewritable IC card according to claim 1 of the present invention uses a personal IC card via a public network to mutually authenticate whether or not content can be distributed with a service distribution organization. In the rewritable IC card to be used, the IC card and the service distribution organization have a key paired with an encryption algorithm of a public key method or a secret key method, and the IC card has two or more rewritable keys. An authentication key that has an array and can be rewritten only once, and each time the authentication key is rewritten, the service distribution organization and the IC card perform mutual authentication using an authentication key different from the previous one. It is characterized by.

  The rewritable IC card according to claim 2 of the present invention is the rewritable IC card according to claim 1, wherein the rewritable IC card according to claim 1 is the initial one when the IC card is issued. An access count holding means for holding the number of accesses in which a value is set and the value changes every time the service distribution organization is accessed, and an access calculation value for the access count set when the IC card is issued An access calculation value holding means for performing a predetermined calculation using the access calculation value for the number of accesses every time the service distribution organization is accessed using the IC card after the IC card is issued. The number of accesses is updated using the result, and used for the next mutual authentication.

  Furthermore, the rewritable IC card according to claim 3 of the present invention is the rewritable IC card according to claim 1, wherein the IC card has a key validity period having a predetermined value determined when the IC card is issued, And the IC card compares the time data of a timer of a network terminal used for accessing the service distribution organization with the key validity period, and the validity period expires. If so, the key used for mutual authentication of the IC card is updated.

  According to the rewritable IC card according to the present invention, there is an effect that an IC card having a strong mutual authentication safety via a public network and an easy configuration can be obtained.

  That is, according to the rewritable IC card according to claim 1 of the present invention, when the authentication key is updated, an authentication key that has not been used until now is used, and the authentication key can be rewritten only once. Since the resource configuration for holding the key in the key update is simple, there is an effect that the security of the authentication key update can be improved.

  Further, according to the rewritable IC card according to claim 2 of the present invention, since the parameter that is different for each individual of mutual authentication and updated every time access is used, the security of the authentication key can be improved. There is.

  Furthermore, according to the rewritable IC card according to claim 3 of the present invention, since the key is updated while periodically performing mutual authentication, there is an effect that the security of the key can be further improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The rewritable IC card of the present invention has the following functions.
(1) It has two or more rewritable keys used for authentication using an encryption algorithm, and a key that can be used only once for authentication key update.
(2) It has a different authentication pattern for each personally set access.
(3) A personally set key expiration date is set and automatic updating is possible.

(Embodiment 1)
The first embodiment has the functions (1) and (2) described above.

  FIG. 1 is a diagram showing a configuration of mutual authentication between an IC card and a media distribution organization according to Embodiment 1 of the present invention.

  In FIG. 1, 300 is an authentication key holding unit A that holds a first authentication key, 301 is an authentication key holding unit B that holds a second authentication key, and 302 is an authorized cardholder at the time of registration of the IC card 100. An access count holding unit (access count holding means) for holding the set access count indicating a value corresponding to the access count to the media distribution organization 102, 303 is set by the authorized cardholder when the IC card 100 is registered , An access calculation value holding unit (access calculation value holding means) for holding an access calculation value for changing the number of accesses every time the media distribution organization 102 is accessed; 304 is set when the IC card 100 is registered The key validity period holding unit (key validity period holding means) for holding the key validity period, 305 is built in the network terminal and indicates the date and time. A timer for generating time data, 306 is a registration key A that is set when the IC card 100 is registered, and that is paired with the authentication key holding unit A300, and 307 is a pair that is set when the IC card 100 is registered and the authentication key holding unit B301 is paired The registration key B, 308 is the same registered access count as the access count holding unit 302 set when registering the IC card 100, and 309 is the same registered access calculation value as the access calculation value holding unit 303 set when registering the IC card 100. . The same parts as those in FIG. 4 are denoted by the same reference numerals.

  Next, renewal of the mutual authentication key according to the first embodiment in the configuration of FIG. 1 will be described using the flowchart of FIG.

  Prior to mutual authentication, when the IC card 100 is issued, values desired by the card holder are set as initial values and set values in the access count holding unit 302 and the access calculation value holding unit 303, respectively. Also, authentication keys A and B are set in authentication key holding units A300 and B301, respectively. Further, the media distribution institution 102 associates the authentication keys A and B, the access count and the access calculation value with the registration keys A 306 and B 307, the registered access count 308 and the registration access calculation value 309 with the unique ID 103 of the IC card 100. Set above. Further, the calculation for the access count is set so that the same is used on the IC card 100 side and the media distribution institution 102 side.

  First, in order to perform mutual authentication, by connecting the IC card 100 to the network terminal 108, the IC card communicates with the media distribution organization 102 via the I / F 109 and the network 101 connected to the network terminal 108.

  The mutual authentication and key update operation between the IC card 100 of the present invention and the media distribution organization 102 is as follows.

  That is, as shown in FIG. 2, the IC card 100 encrypts the access count of the access count holding unit 302 in step 400 by using the authentication key of the authentication key holding unit B301 under the control of the CPU 107, and creates a ciphertext e5. The ciphertext e5 and the unique ID 103 are transmitted to the media distribution institution 102 via the network 101. In step 401, the access calculation value of the access calculation value holding unit 303 is added to the access count, and this is accessed as the next access count. The number is stored in the number holding unit 302.

  The media distribution institution 102 decrypts the ciphertext e5 in step 402 by using the registration key B307 searched from the unique ID 103 to create a plaintext d5, and then in step 403, the access count included in the plaintext d5, Compared with the registered number of registered accesses 308, if it does not match (no), the communication ends as authentication NG, and if it matches (yes), as authentication OK, the next step 404 uses an authentication key generation algorithm or the like A new authentication key is generated, and then in step 405, a registration access operation value is added to the registration access count 308 to create a next registration access count, and in step 406, the registration access count and the new authentication key are registered as registration keys. B is encrypted to create a ciphertext e6, and the ciphertext e6 is And transmits to the IC card 100 via the click 101.

  The IC card 100 creates the plaintext d6 by decrypting the ciphertext e6 with the key of the authentication key holding unit B301 in step 407, and then creates the next registered access count included in the plaintext d6 and in step 401 in step 408. In the next step 409, the step 404 included in the plaintext d6 assumes that the communication is terminated as an authentication NG when the number of times of the next access is not matched (no), and the communication is terminated as an authentication NG. The new authentication key created in step 3 is updated by setting it in the authentication key holding unit A, and the next access number created in step 401 is updated in the access number holding unit 302. In step 410, the media distribution organization 102 is notified that the update has been completed.

  In step 411, the media distribution institution 102 can update the authentication key by setting the number of times of the next registration access created in step 405 as the number of registration accesses.

If the mutual authentication is OK, the media distribution organization starts distributing content to the network that has performed the mutual authentication.
Thereafter, the following step A, B, C, and D are repeated.

  step A: In the mutual authentication when the authentication key is updated, the authentication key of the authentication key holding unit B301 is used.

  step B: When updating the authentication key holding unit B301, the authentication key holding unit B301 is updated using the authentication key of the authentication key holding unit A300.

  step C: In the mutual authentication when the authentication key is updated, the authentication key of the authentication key holding unit A300 is used.

  stepD: When updating the authentication key holding unit A300, the authentication key holding unit B301 is updated using the authentication key of the authentication key holding unit A300.

  Thereby, when updating the authentication key, an authentication key that can be used only once is used for updating the authentication key, and the security of updating the authentication key can be increased.

  As described above, in the rewritable IC card according to the first embodiment, whether or not content can be distributed with a service distribution organization using a personal IC card via a public network is encrypted. In a mutual authentication system, an IC card and a service distribution organization have a key paired with a public key method or a secret key method encryption algorithm, and the IC card has two or more rewritable key arrays. The IC card has a key that can be used only once to rewrite the authentication key. Each time the authentication key is rewritten, the IC card performs mutual authentication using a different key. An initial value is set when the card is issued, and the IC card has a means for holding the number of accesses in which the value changes every time the media distribution organization is accessed. A means for holding an access calculation value set at the time of issuing the service code, and each time the service distribution organization is accessed using an IC card after the issuance, a predetermined value is used for the access count using the access calculation value. The result is updated as the number of times of access and used for the next mutual authentication, so it changes for each access in the mutual authentication of communication through the IC card and the public network in the service provider. Authentication can be performed using the number of accesses to be performed, and an efficient and safer rewritable IC card can be obtained.

  In the first embodiment, the number of accesses is set at the time of IC card issuance and used for authentication. However, it is initially set at the time of IC card registration, and it is different for each individual and updated every time it is accessed. Authentication can be performed using different authentication patterns, and the security of authentication can be further increased.

  That is, the access count initially set in the access count holding unit 302 may be a value “0” reflecting the actual access count, or may be a desired value unrelated to this. The value initially set in the access calculation value holding unit 303 may be a value “1” reflecting an increase in the actual number of accesses, but may be a desired value other than this.

  These settings can also be made by an authorized owner of the IC card by operating the network terminal after connecting the IC card 100 to the network terminal 108 (installing in the slot of the terminal 108, etc.). In this case, it is only necessary to notify the media distribution organization 102 of the access count and the set value of the access calculation value holding unit 303 by a method capable of maintaining the secret.

  Further, the calculation for obtaining the number of accesses may be performed by adding “1” or subtracting “1” to the previous number of accesses reflecting the increase in the actual number of accesses. As long as the values are different, more complicated calculation may be performed, and this can further increase the security of authentication.

  The IC card may be configured more simply by having one holding means for holding two authentication keys and rewriting the authentication keys alternately.

(Embodiment 2)
The second embodiment has the above feature (3) (key expiration date and automatic update thereof).

  FIG. 3 is a diagram showing the configuration of the key validity period holding unit 304 in the rewritable IC card according to the second embodiment of the present invention. In FIG. 3, 500 is update data indicating the date and time of the previous update, and 501 is This is valid period data indicating the valid period of the key, and is determined when the IC card 100 is issued. Here, the same parts as those in FIG.

  The automatic update of the mutual authentication key according to the second embodiment having the configuration shown in FIG. 3 will be described below.

  First, for mutual authentication, by connecting the IC card 100 shown in FIG. 1 to the network terminal 108, the IC card communicates with the media distribution organization 102 via the network 101 connected to the network terminal 108 through the I / F 109. However, at this time, the CPU 107 of the IC card 100 subtracts the update data 500 (see FIG. 3) indicating the date and time when the IC card 100 updated the previous key from the date and time indicated by the timer 305 of the network terminal 108. Then, it is confirmed whether or not it is larger than the validity period data 501 (see FIG. 3) indicating the validity period of the key, and if this is larger, the key is updated by the mutual authentication of the first embodiment.

  In such a rewritable IC card according to the second embodiment, the IC card has means having a predetermined value determined when the IC card is issued as a key validity period unique to the IC card. The timer of the network terminal used for accessing the service distribution organization is compared with the key validity period, and when the validity period has expired, the key used for mutual authentication of the IC card is updated. Therefore, by updating the key while periodically performing mutual authentication, it is possible to enhance the security.

  In the first and second embodiments, an example is shown in which mutual authentication between a media distribution organization and an IC card is performed. However, as long as data can be exchanged only with an authorized network terminal user. However, the present invention is not limited to a media distribution institution or service distribution institution, and may be a case where mutual authentication is performed between a computer system such as a server for various electronic commerce and the like and an IC card of a network terminal. The effect is obtained.

  Also, in the first and second embodiments, the method for setting the key validity period is not particularly mentioned, but this is set on the card manufacturer side when the IC card is issued, like the access count and the access calculation value. Alternatively, the authorized owner of the card may operate the network terminal on which the IC card is mounted and write it on the IC card.

  As described above, according to the rewritable IC card of the present invention, by connecting the IC card to the network terminal, the network terminal connected via the public network and the server such as a service distribution organization It is suitable for enhancing security when performing mutual authentication.

Configuration diagram of a mutual authentication system using an IC card in Embodiment 1 of the present invention Flowchart diagram of mutual authentication in Embodiment 1 of the present invention Configuration diagram of key validity period holding unit in rewritable IC card according to Embodiment 2 of the present invention Configuration diagram of mutual authentication system using IC card according to conventional example Flowchart diagram of mutual authentication in the conventional example

Explanation of symbols

100 IC card 101 Network 102 Media distribution organization 103 Unique ID which is an identification code different for each individual
104 Authentication Key Holding Unit Holding an Authentication Key 105 Authentication Password Holding Unit Holding an Authentication Password 106 Random Number Generator 107 Generating a Random Number
108 Network terminal 109 I / F with network terminal
110 Registration ID for identifying an individual with the same identification code as the unique ID
111 Registration Key Having Authentication Key Paired with Authentication Key Holding Unit 112 Registration Password 300 having Same Password as Authentication Password Holding Unit Authentication Key Holding Unit A Holding First Authentication Key
301 Authentication key holding unit B holding the second authentication key
302 Access count storage unit 303 that differs for each access 303 Access calculation value storage unit 304 that has a calculation value used to generate the access count Key validity period storage unit 305 that stores the key validity period Timer 306 that indicates the current date and time Authentication key storage unit Registration key A with authentication key paired with A
307 Registration key B having an authentication key paired with authentication key holding unit B
308 Registered access count 309 having the same access count as the access count holding section 309 Registered access calculation value 500 having the same calculation value as the access calculation value holding section Update data 501 indicating the date and time when the authentication key was last updated Lifetime data

Claims (3)

In a rewritable IC card used in a system that mutually authenticates whether or not content can be distributed with a service distribution organization using a personal IC card via a public network,
The IC card and the service distribution organization have a key paired with a public key method or a secret key method encryption algorithm,
The IC card has two or more rewritable key arrays and an authentication key that can be rewritten only once.
Each time the authentication key is rewritten, the service distribution organization and the IC card perform mutual authentication using an authentication key different from the previous one.
A rewritable IC card characterized by that. In the rewritable IC card according to claim 1,
The IC card is
An initial value is set when the IC card is issued, and an access count holding means for holding an access count that changes every time the service distribution organization is accessed;
An access calculation value holding means for holding an access calculation value for the number of accesses set when the IC card is issued,
After issuing an IC card, every time the service distribution organization is accessed using the IC card, a predetermined calculation is performed on the access count using the access calculation value, and the access count is updated using the result. Used for the next mutual authentication,
A rewritable IC card characterized by that. In the rewritable IC card according to claim 1,
The IC card is
A key validity period holding means for holding a key validity period having a predetermined value determined at the time of issuing the IC card;
The IC card is used for mutual authentication of the IC card when the validity period has expired by comparing clock data of a timer of a network terminal used for accessing the service distribution organization and the key validity period. Renew the key,
A rewritable IC card characterized by that.

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