JP2010225000A - Password setting system for detachable recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent that data of a detachable recording medium is leaked to a person except a user, and to update of a safe password without input and storage of the password by the user. <P>SOLUTION: In this password setting system, a computer for being mounted with the detachable recording medium, a server, and a mobile terminal are connected via a communication network. When the detachable recording medium is mounted in the computer, the password stored by the detachable recording medium is transmitted to the server via the computer. When the server having received the password (a reception password) receives a processing request of encryption release from the mobile terminal, the server creates a new password that is a substitute of the reception password. The server transmits the new password and the reception password to the computer, and the computer transmits the new password and the reception password to the detachable recording medium. The detachable recording medium decodes data of a storage part by use of the received reception password by reception of the new password and the reception password, and changes the password into the new password. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a password setting method for a removable recording medium.

  In recent years, a so-called removable recording medium that can be mounted on a personal computer, a portable terminal, or the like only when necessary to write or read data has come to be easily used. The removable recording medium is also referred to as a removable (removable) medium. As a typical example, a memory card (Memory Card), a USB (Universal Serial Bus) memory, or a removable HDD (Hard Disk) is used. (Drive: hard disk drive).

  Such a detachable recording medium is small and easy to carry, but in the case of loss, there is a concern about leakage of recorded data. Therefore, as one method for preventing such data leakage, there is a method in which recorded data is encrypted (see, for example, Patent Document 1).

  The following description is made in Patent Document 1 “Electronic Data Protection Method” described above.

  That is, a computer that sells software and permits use of the software encrypts electronic data such as software and stores it in a recording medium such as a magneto-optical disk. Also, a medium unique key is generated based on the medium unique number of the recording medium, the decryption key of the encrypted digitized data is encrypted with this medium unique key, and this is stored in the recording medium as permission information. A computer that purchases and uses computerized data such as software generates a medium unique key based on the medium unique number of the recording medium, and decrypts the permission information in the recording medium using the medium unique key. Generate a decryption key. Then, with this decryption key, the encrypted digitized data read from the recording medium is decrypted and returned to the plaintext digitized data. By doing so, it is possible to give permission to execute the digitized data (software etc.) to the medium unique number and to protect the digitized data recorded on the recording medium. .

  In addition, in order to prevent leakage of data recorded on a removable recording medium, not only data is encrypted but also data is encrypted based on a password (for example, patents). Reference 2).

  The following description is made in the above-described Patent Document 2 “Image Data Communication Device”.

  That is, the image data communication device includes image data transmitted from a remote device, a communication unit that receives a telephone number of the remote device, and a recording / reading unit to which an external memory is detachably attached. Then, the image data communication device stores the image data received by the communication unit in the external memory in association with the telephone number of the remote device. In addition, when storing image data in an external memory, ID (IDentifier) information corresponding to a telephone number may be used as a password. That is, since the image data is encrypted based on the ID information, unauthorized access to the image data can be effectively prevented.

  Furthermore, in order to prevent leakage of data recorded on a detachable recording medium, software for encrypting data and enabling a password to be set has been sold (for example, non-patented). Reference 1).

  The software of Non-Patent Document 1 described above can encrypt a data file stored in a removable medium and set a password. The encrypted data file can be referred to for the first time by inputting the correct password that has been set. By doing so, unauthorized access to the encrypted file can be prevented.

JP-A-5-257816 (page 2-8, FIG. 1-14) JP 2004-048214 A (Page 5-10, FIG. 1-6)

BH Corporation (BHA), data encryption software “B ’s File Guard” product information “http://www.bha.co.jp/products/file_guard/index.html”

  As described above, as a technique for preventing leakage of data recorded on a detachable recording medium, a method of simply encrypting data as described in Patent Document 1 has been common. However, in recent years, as described in Patent Document 2 or Non-Patent Document 1, not only data encryption but also a password for data encryption can be set.

  A method in which a password for encryption in addition to data encryption can be set is considered desirable as a more useful method for preventing leakage of data on a removable recording medium. However, on the other hand, the user of the detachable recording medium has an aspect that the set password must be stored. That is, when the set password is not stored and forgotten, there is a problem that the data recorded after encryption cannot be decrypted and returned to plain text data.

  The present invention has been made to solve the above-described problems. Accordingly, an object of the present invention is to provide a password setting method for a detachable recording medium, which prevents data leakage to non-users and enables safe password updating without password storage and input by the user. It is to provide.

  The removable recording medium password setting method of the present invention includes a first storage unit that stores data, a second storage unit that stores a password for encryption, and a control that performs operation control including data encryption. A detachable recording medium including a portion. Further, the computer includes a computer to which a detachable recording medium can be mounted, and a server for communication connection with the computer. Furthermore, a mobile terminal that is connected to communicate with the server is included.

  When the removable recording medium is attached to the computer, the control unit of the removable recording medium causes the password to be transmitted to the server via the computer. When the server receiving the password receives a decryption processing request from the mobile terminal, the server creates a new password as a substitute for the password, sends the new password and the password to the computer, and the computer The password and the password are sent to a removable recording medium. The control unit of the detachable recording medium decrypts the data using the received password and receives the new password and changes the password stored in the second storage unit to the new password. ing.

  The removable recording medium password setting method of the present invention is a removable recording medium password setting method for storing data and a password for encryption. When the removable recording medium is attached to the computer, the password stored in the removable recording medium is transmitted to the server. Next, based on the decryption processing request, the server creates a new password as a substitute for the password, and sends the new password and the password to the removable recording medium. Furthermore, data is decrypted using the password received by the removable recording medium, and the password stored in the removable recording medium is changed to a new password.

  The removable recording medium of the present invention is a removable recording medium for storing data and a password for encryption. When the removable recording medium is attached to the computer, the password is transmitted to the server via the computer, and when the new password and the password are received from the server, the data is decrypted using the received password. In addition, a control unit for changing the password to a new password is included.

  The server of the present invention is a server that can be communicably connected to a computer and a portable terminal. When the password of the removable recording medium attached to the computer is received and the decryption processing request is received from the portable terminal, a new password is created as an alternative to the password, and the new password and the password are transferred to the computer. A control unit for transmission is included.

  The password recording method in the removable recording medium of the present invention is a method performed by a removable recording medium that stores a password. Then, when a removable recording medium is attached to the computer, a new password request including the password is transmitted, and when the new password and the password are received as a response to the new password request, the password is changed to the new password. I am trying to change it.

  The new password setting method in the server of the present invention is a method performed in the server. When a new password request including a password is received, a new password is created as an alternative to the password based on the decryption processing request, and the new password and the password are used as a response to the new password request. I am trying to send it out.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to prevent the data of a detachable recording medium from leaking to others, a safe password can be updated without storing and inputting a password by the user.

It is a block diagram which shows 1st Embodiment of the password setting system of the removable recording medium of this invention. It is a sequence diagram explaining operation | movement of 1st Embodiment. It is a block diagram which shows 2nd Embodiment of the password setting system of the removable recording medium of this invention. It is a detailed block diagram which shows the structure of the detachable recording medium and computer of 2nd Embodiment. It is a 1st sequence diagram explaining the operation | movement which registers the information regarding the removable recording medium of 2nd Embodiment with a server. It is a 2nd sequence diagram explaining the operation | movement which registers the information regarding the removable recording medium of 2nd Embodiment with a server. It is a figure which shows an example of the information regarding the removable recording medium registered into the memory | storage part of a server. FIG. 11 is a sequence diagram illustrating an operation when a removable recording medium is removed from a computer. It is a sequence diagram explaining operation | movement at the time of remounting a removable recording medium to a computer.

Next, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
FIG. 1 is a block diagram showing a first embodiment of a password setting method for a removable recording medium according to the present invention.

  In the present embodiment illustrated in FIG. 1, a computer 20 on which a removable recording medium 10 can be mounted, a server 30, and a mobile terminal 40 are connected via a communication network 50.

  The detachable recording medium 10 is a recording medium that can be attached to a personal computer or a portable terminal, such as a memory card, a USB memory, or a removable HDD, only when necessary, and can write or read data. is there.

  The detachable recording medium 10 shown in FIG. 1 includes a control unit 19, a storage unit 13 corresponding to a first storage unit, and a control information storage unit 14 corresponding to a second storage unit.

  The control unit 19 controls the operation of the entire detachable recording medium 10 and executes various functions of the detachable recording medium 10. In particular, the control unit 19 has a function of encrypting data stored in the storage unit 13 by using a password stored in the control information storage unit 14. The detachable recording medium 10 includes an internal power supply (not shown), and the control unit 19 is operated by electric power supplied from the internal power supply.

  The storage unit 13 is an area for storing and storing data written from the computer 20.

  The control information storage unit 14 stores a password 141 for performing encryption sent from the control unit 19.

  The removable recording medium 10 stores in advance a production number for individually identifying the removable recording medium 10.

  The computer 20 is an information processing apparatus such as a personal computer. The computer 20 is attached to the removable recording medium 10 when necessary, and writes data to the removable recording medium 10 or reads data from the removable recording medium 10. It is possible to do. Further, when the removable recording medium 10 is loaded, the computer 20 receives the removable recording medium control program from the removable recording medium 10 and operates the program so that the removable recording medium 10 can be used. Control is to be performed.

  The server 30 is an information processing apparatus such as a workstation server and includes a control unit 31.

  The control unit 31 transmits and receives electronic mail to and from the computer 20. If the received e-mail is related to the removable recording medium 10, a password for data encryption is generated and transmitted to the computer 20. The control unit 31 communicates with the mobile terminal 40, receives a processing request instructed from the mobile terminal 40, and performs control according to the received processing request.

  In the server 30, a manufacturing number for individually identifying the removable recording medium 10 and a telephone number of the portable terminal 40 owned by the user of the removable recording medium 10 are registered in advance.

  The mobile terminal 40 is a portable terminal device such as a mobile phone, a PHS (Personal Handyphone System) terminal, or a PDA (Personal Digital Assistant). The portable terminal 40 communicates with the server 30 and sends a processing request to the server 30.

  The communication network 50 is the Internet that connects a computer network, a telephone exchange network, a mobile communication network, a corporate intranet, and the like.

  Next, the operation of the present embodiment will be described with reference to FIG.

  Here, the use of the password in the present embodiment will be described in advance.

  First, the data stored in the storage unit 13 of the removable recording medium 10 is encrypted with the password 141 of the control information storage unit 14 before the operation in the present embodiment starts.

  In this embodiment, when the detachable recording medium 10 is attached to the computer 20, the encrypted data in the storage unit 13 is not immediately decrypted, but first, a new password 141 including the password 141 is read from the detachable recording medium 10. A password request is sent to the server 30.

  When the server 30 receives a new password request including a password 141 (hereinafter referred to as a received password), the server 30 guides the mobile terminal 40 to transmit a processing request instructed by the mobile terminal 40. When receiving an instruction for decryption processing from the portable terminal 40, the server 30 creates a new password as a substitute for the password 141, and transmits the new password and the received password to the computer 20. The computer 20 sends the new password and the received password to the removable recording medium 10.

  Here, the removable recording medium 10 decrypts the encrypted data in the storage unit 13 using the reception password. Thereafter, the removable recording medium 10 changes the password 141 stored in the control information storage unit 14 to a new password.

  Since the encrypted data in the storage unit 13 of the removable recording medium 10 is decrypted in this way, the computer 20 can access the data in the storage unit 13 of the removable recording medium 10 thereafter.

  FIG. 2 is a sequence diagram for explaining the operation of the first embodiment.

  First, the removable recording medium 10 storing the encrypted data in the storage unit 13 is loaded into the computer 20 (step S11 in FIG. 2).

  The controller 19 of the detachable recording medium 10 attached to the computer 20 first reads a detachable recording medium control program executed by the computer 20 from a program storage unit (not shown) and sends it to the computer 20. . Receiving the program, the computer 20 starts the operation by interrupting the program that has been operating until then.

  Next, the control unit 19 reads the password 141 stored in the control information storage unit 14 (step S12). Then, based on the program, the control unit 19 sends the serial number of the removable recording medium 10 and the password 141 to the computer 20 (step S13).

  When the computer 20 receives the production number and password 141 from the removable recording medium 10, the computer 20 activates a predetermined e-mail program to generate an e-mail describing the production number and password 141, and sends it to the server 30 (step). S14).

  In the server 30 that has received the e-mail from the computer 20, the control unit 31 determines the user of the removable recording medium 10 from the serial number of the removable recording medium 10, calls the mobile terminal 40 owned by the user, and makes a call. . Then, the mobile terminal 40 is instructed to transmit a processing request instructed by the mobile terminal 40 (step S15).

  The user of the portable terminal 40 who has heard this guidance instructs the decryption processing as a processing request (step S16).

  The control unit 31 of the server 30 that has received the decryption processing instruction from the portable terminal 40 creates a new password for the removable recording medium 10 to encrypt data (step S17). Then, the control unit 31 creates an e-mail in which the created new password and the password received from the removable recording medium 10 (the password 141 received in step S14, hereinafter referred to as the received password) are written to the computer 20. It transmits to (step S18).

  The computer 20 sends the new password and the received password described in the received e-mail to the removable recording medium 10 (step S19). This sending is executed based on the aforementioned program received from the removable recording medium 10.

  The control unit 19 of the detachable recording medium 10 performs a process of decrypting the data in the storage unit 13 and returning it to plain text data using the received password received from the computer 20 (step S20).

  Next, the control unit 19 stores the new password received from the computer 20 as the password 141 in the control information storage unit 14 (step S21).

  As described above, the password setting method of the removable recording medium according to the present embodiment includes the storage unit 13 that stores data, the control information storage unit 14 that stores the password 141 for encryption, and the data encryption. A removable recording medium 10 including a control unit 19 that performs operation control is included. Further, the computer 20 includes a computer 20 on which the removable recording medium 10 can be mounted, and a server 30 that communicates with the computer 20. Furthermore, a mobile terminal 40 that is connected to the server 30 for communication is included.

  When the detachable recording medium 10 is attached to the computer 20, the control unit 19 of the detachable recording medium 10 transmits the password 141 to the server 30 via the computer 20. When the server 30 that has received the password 141 (received password) receives a decryption processing request from the portable terminal 40, the server 30 creates a new password that is an alternative to the received password. Then, the server 30 transmits the new password and the received password to the computer 20. The computer 20 sends the new password and the received password to the removable recording medium 10. Upon receiving the new password and the received password, the control unit 19 of the removable recording medium 10 decrypts the data using the received received password, and changes the password 141 stored in the control information storage unit 14 to the new password. To do. Specifically, the new password is stored in the control information storage unit 14 instead of the password 141.

  That is, the server 30 creates a new password each time the removable recording medium 10 is loaded into the computer 20 and sends the new password to the removable recording medium 10. The removable recording medium 10 replaces the original password 141 with a new password.

Therefore, according to the present embodiment, it is possible to prevent the data on the removable recording medium from leaking to anyone other than the user and to update the password safely without storing and inputting the password by the user.
[Second Embodiment]
Next, a second embodiment according to the present invention that further embodies the first embodiment shown in FIG. 1 will be described.

  FIG. 3 is a block diagram showing a second embodiment of the password setting method for the removable recording medium of the present invention. 3 that correspond to the components shown in FIG. 1 are denoted by the same reference numerals or symbols, and the description thereof is omitted as much as possible.

  In the present embodiment illustrated in FIG. 3, a computer 20 on which the removable recording medium 10 can be mounted, a server 30, and a mobile terminal 40 are connected via a communication network 50. In addition, a gateway 60, a voice response device 70, and a certificate authority server 90 are connected to the communication network 50. The server 30, the gateway 60, and the voice response device 70 are connected to each other via a LAN (Local Area Network) 80.

  The detachable recording medium 10 is a recording medium that can be attached to a personal computer or a portable terminal, such as a memory card, a USB memory, or a removable HDD, only when necessary, and can write or read data. is there. The detachable recording medium 10 includes a storage unit (not shown in FIG. 3), and data recorded in the storage unit can be encrypted using a password as a key. The detachable recording medium 10 includes a control unit (not shown in FIG. 3), and the control unit has a function of controlling the operation of the entire detachable recording medium 10. The details of the removable recording medium 10 will be described later with reference to FIG.

  The computer 20 is an information processing apparatus such as a personal computer. The computer 20 is attached to the removable recording medium 10 when necessary, and writes data to the removable recording medium 10 or reads data from the removable recording medium 10. It is possible to do. Further, when the removable recording medium 10 is loaded, the computer 20 receives the removable recording medium control program from the removable recording medium 10 and operates the program so that the removable recording medium 10 can be used. Control. Details of the computer 20 will be described later with reference to FIG.

  The server 30 is an information processing apparatus such as a workstation server, and includes a control unit 31 and a storage unit 32.

  The control unit 31 transmits and receives electronic mail to and from the computer 20. If the received e-mail is related to the removable recording medium 10, a password for data encryption is generated and transmitted to the computer 20. In addition, the control unit 31 communicates with the mobile terminal 40 and performs control according to a processing request instructed from the mobile terminal 40. Further, the control unit 31 communicates with the certificate authority server 90 to acquire an electronic certificate necessary for authentication of the removable recording medium 10 and the computer 20, and stores the electronic certificate in the storage unit 32 and the computer. 20 is also sent out.

  The storage unit 32 stores information related to the removable recording medium 10 and stores, for example, a password for performing encryption, an electronic certificate acquired from the certificate authority server 90, and the like.

  The portable terminal 40 is a portable terminal device such as a cellular phone, a PHS terminal, or a PDA. The portable terminal 40 communicates with the server 30 and communicates with the voice response device 70 using voice or operation buttons. Then, the portable terminal 40 sends a processing request to the server 30 via the voice response device 70.

  The communication network 50 is an Internet that connects a computer network, a telephone exchange network, a mobile communication network, an intranet in a company, and the like using a communication protocol TCP / IP (Transmission Control Protocol / Internet Protocol). . The computer 20, the server 30, the mobile terminal 40, the gateway 60, the voice response device 70, the certificate authority server 90, and the like are connected by communication network 50.

  The gateway 60 is a communication device having a call connection function of VoIP (Voice over Internet Protocol) that transmits and receives voice data on a network using TCP / IP. The gateway 60 includes a control unit 61 and a call connection unit 62.

  When receiving the call connection instruction from the server 30, the control unit 61 controls the call connection unit 62 to connect the instructed call to the instructed connection destination. The call connection unit 62 connects the call instructed by the control unit 61 to the instructed connection destination.

  The voice response device 70 is an information processing device having a voice response function such as a workstation / server, and includes a control unit 71, a voice response unit 72, and a voice recognition unit 73.

  When receiving a call, the control unit 71 obtains the caller telephone number of the telephone caller and issues an instruction to the voice response unit 72 to provide guidance for transmitting a processing request instructed by the telephone caller. The voice response unit 72 provides voice guidance to the caller. The voice recognizing unit 73 recognizes the voice transmitted from the telephone caller according to the voice guidance of the voice response unit 72 or the type of the operation button pressed by the telephone caller. Then, the contents of the processing request of the telephone caller determined from the recognition result are converted into text. The voice recognition unit 73 sends the text to the control unit 71, and the control unit 71 sends the text to the server 30 via the LAN 80.

  The certificate authority server 90 is an organization that issues an electronic certificate or the like that certifies that a sender such as an e-mail transmitted / received on the Internet is a legitimate sender, that is, a certification authority (CA), An information processing apparatus such as a workstation server installed in the computer. The certificate authority server 90 has a function of issuing the above-described electronic certificate by e-mail.

  Next, the configuration of the removable recording medium 10 and the computer 20 of this embodiment will be described in detail with reference to FIG.

  FIG. 4 is a detailed block diagram illustrating the configuration of the removable recording medium and the computer according to the second embodiment. 4 that correspond to the components shown in FIG. 3 are denoted by the same reference numerals or symbols, and the description thereof is omitted as much as possible.

  4 includes a control unit 11, an encryption setting / cancellation unit 12, a storage unit 13, a control information storage unit 14, a serial number storage unit 15, a connection unit 16, a detachment detection unit 17, and a storage unit 18. Is included.

  The control unit 11 controls the operation of the entire detachable recording medium 10 and executes various functions of the detachable recording medium 10. In addition, the control unit 11 stores various data generated or used by executing each function in the storage unit 13 or the control information storage unit 14, or reads out and uses the data from the storage unit 13 or the control information storage unit 14. To do.

  When the encryption setting / release unit 12 is instructed by the control unit 11 to encrypt data in the storage unit 13, the encryption setting / cancellation unit 12 stores the password stored in the control information storage unit 14 as a key for encryption. Data stored in the unit 13 is encrypted. Further, when the control unit 11 is instructed to decrypt the encrypted data in the storage unit 13, the encrypted data stored in the storage unit 13 using the password instructed by the control unit 11 as a key for decryption. Is decrypted.

  The storage unit 13 is an area for storing and storing data written from the computer 20, and is configured by a non-volatile flash memory or the like.

  The control information storage unit 14 is a storage area configured by a non-volatile flash memory or the like, and stores a password 141 sent from the control unit 11 for encryption. The control information storage unit 14 also includes an initialization password 142 for initializing the removable recording medium 10, an unencryptable password 143 for disabling data decryption of the removable recording medium 10, The electronic certificate 145 is stored.

  The production number storage unit 15 is an area for storing the production number 151 of the detachable recording medium 10 and is composed of a ROM (Read Only Memory) in which the contents once written cannot be rewritten. The serial number of the removable recording medium 10 is a number unique to the removable recording medium 10 and is written in the serial number storage unit 15 when the removable recording medium 10 is manufactured. Further, this serial number is printed on the surface of the main body of the removable recording medium 10, the case or the outer box, and can be recognized visually.

  The connection unit 16 is a connector connected to the computer 20, and sends a signal indicating whether or not the computer 20 is connected to the attachment / detachment detection unit 17. When connected to the computer 20, the connection unit 16 transmits and receives data to and from the computer 20.

  The attachment / detachment detection unit 17 detects whether or not the removable recording medium 10 is attached to the computer 20 based on a signal from the connection unit 16 and sends a detection signal to the control unit 11.

  The storage unit 18 stores a program for realizing various functions of the removable recording medium 10 and a program for controlling the removable recording medium executed by the computer 20.

  The detachable recording medium 10 shown in FIG. 4 includes an internal power supply (not shown), and the control unit 11, the encryption setting / cancellation unit 12 and the like are operated by power supplied from the internal power supply. .

  4 includes a control unit 21, a storage unit 22, a connection unit 23, a communication unit 24, an operation unit 25, and a display unit 26.

  The control unit 21 controls the operation of the entire computer 20 and causes the computer 20 to execute various functions. The control unit 21 stores various data generated or used by executing each function in the storage unit 22 or the removable recording medium 10, or reads out from the storage unit 22 or the removable recording medium 10 for use. To do.

  The storage unit 22 stores programs for realizing various functions of the computer 20, setting data for each function, or various data generated by each function and used by each function.

  The connection unit 23 is a connector that connects to the removable recording medium 10. The connection unit 23 transmits / receives data to / from the removable recording medium 10 when the removable recording medium 10 is connected.

  The communication unit 24 is communicatively connected to the communication network 50 by wired communication or wireless communication.

  The operation unit 25 inputs commands and data for operating the computer 20.

  The display unit 26 displays various data output from the computer 20.

  Next, the operation of this embodiment will be described.

  Here, the premise of the present embodiment will be described in advance.

  In the present embodiment, when the removable recording medium 10 is unused, for example, by newly purchasing the removable recording medium 10, information regarding the removable recording medium 10 is registered in the server 30. is required. That is, by registering information about the removable recording medium 10 in the server 30, it is possible to write data to the removable recording medium 10 or read data from the removable recording medium 10 thereafter. It comes to become. When the removable recording medium 10 is unused, the serial number of the removable recording medium 10 is stored in the serial number storage unit 15 of the removable recording medium 10. However, the storage unit 13 of the removable recording medium 10 is in an initial state in which no data is stored, and the password 141, the initialization password 142, the unencryptable password 143 of the control information storage unit 14, and The area of the electronic certificate 145 is also in a state where nothing is stored, that is, a state where a null (NULL) string is written.

  Further, in the present embodiment, when the information related to the removable recording medium 10 is registered from the computer 20 to the server 30, the computer 20 uses an e-mail that conforms to the S / MIME (Secure Multipurpose Internet Extensions) standard. Information is transmitted. Also, when the server 30 notifies the computer 20 of response information, an electronic mail based on the S / MIME standard is used.

  S / MIME is a standard for encrypted electronic mail using public key cryptography, and utilizes PKI (Public Key Infrastructure). An e-mail sender in accordance with the S / MIME standard attaches an electronic certificate issued from a certificate authority to the e-mail body, and further adds an electronic signature to transmit the e-mail. The receiving side confirms that the e-mail body and the electronic certificate have not been tampered with by confirming the electronic signature added to the e-mail. Also, by comparing the electronic certificate attached to the body of the email with a copy of the electronic certificate that has been passed from the sender in advance, the validity of the electronic certificate is confirmed, and the sender's validity is confirmed. Check. This allows the receiving side to confirm that the received e-mail has been transmitted from a legitimate transmitting side and has not been tampered with. In addition, by sending an e-mail with an electronic certificate attached and an electronic signature, the sender can check the legitimacy of the sender, thereby preventing impersonation on the sender. Is. Note that a hash value of an electronic mail text is usually used as the electronic signature.

  Note that the function of creating and transmitting / receiving S / MIME format electronic mail is executed by the computer 20. In this case, the e-mail is activated and operated based on an instruction from a program stored in the storage unit 18 of the removable recording medium 10, that is, a removable recording medium control program received by the computer 20.

  Next, an operation for registering information about the removable recording medium 10 in the server 30 will be described with reference to FIGS.

  FIG. 5 is a first sequence diagram illustrating an operation of registering information on the removable recording medium of the second embodiment in the server.

  First, the removable recording medium 10 is mounted on the computer 20 (step S101 in FIG. 5).

  Then, the connection unit 16 of the detachable recording medium 10 sends a signal indicating that the detachable recording medium 10 is connected to the computer 20 to the detachment detection unit 17. The attachment / detachment detection unit 17 sends a detection signal indicating that the removable recording medium 10 is attached to the computer 20 to the control unit 11.

  Upon receiving this detection signal, the control unit 11 starts an operation based on a program that realizes its own function stored in the storage unit 18. Then, the control unit 11 reads a removable recording medium control program executed by the computer 20 from the storage unit 18 and sends the program to the computer 20. Receiving the program, the computer 20 starts the operation by interrupting the program that has been operating until then.

  Next, the control unit 11 reads out the production number 151 stored in the production number storage unit 15, and the password 141 and the electronic certificate 145 stored in the control information storage unit 14 (step S102). Then, the control unit 11 sends the serial number 151, the password 141, and the electronic certificate 145 to the computer 20 (step S103). Note that the password 141 and the electronic certificate 145 at this time are both null strings because the removable recording medium 10 is unused.

  The control unit 21 of the computer 20 generates an e-mail text describing the serial number 151 and the password 141 received from the removable recording medium 10. Next, the control unit 21 attaches a null-string electronic certificate 145 to the electronic mail text, and creates an electronic mail in S / MIME format with an electronic signature added. And the control part 21 transmits the said email toward the server 30 via the communication part 24 (step S104).

  In the server 30 that has received the electronic mail from the computer 20, the control unit 31 confirms the validity of the electronic certificate attached to the electronic mail.

  At this time, since the electronic certificate attached to the received e-mail is a null string, the control unit 31 receives the e-mail to register information about the removable recording medium 10 in the server 30. It is assumed that Then, the control unit 31 registers the production number described in the received e-mail in the storage unit 32 as information regarding the removable recording medium 10 (step S105).

  Here, with reference to FIG. 7, information regarding the removable recording medium 10 will be described in advance.

  FIG. 7 is a diagram illustrating an example of information regarding a removable recording medium registered in the storage unit of the server.

  As shown in FIG. 7, the information regarding the removable recording medium includes a plurality of pieces of information shown in lines L1 to L7 for each removable recording medium 10.

  That is, the serial number of the detachable recording medium 10 (L1 line), the electronic certificate issued to the detachable recording medium 10 (L2 line), the mobile terminal 40 owned by the owner of the detachable recording medium 10 The phone number (L3 line) is included. Further, the removable recording medium 10 stores the received password (line L4) indicating the password described in the e-mail from the computer 20. Further, the removable recording medium 10 has a password for encrypting data (line L5), an initialization password for initializing the removable recording medium 10 (line L6), and the removable recording medium 10 The password that cannot be decrypted (L7 line) is included to make it impossible to decrypt the data.

  Returning to FIG. 5, after registering the serial number of the removable recording medium 10 in the storage unit 32 (step S105), the control unit 31 of the server 30 sends the password (in this case, a null string) written in the received e-mail. Is registered in the storage unit 32 as a reception password (L4 in FIG. 7) in the information related to the removable recording medium 10 (step S106).

  Next, the control unit 31 of the server 30 sends an electronic certificate issuance request for the removable recording medium 10 to the certificate authority server 90 (step S107). In this issuance request, the server 30 and the computer 20 are designated as the destination of the electronic certificate.

  The certificate authority server 90 issues an electronic certificate for the removable recording medium 10 and sends the issued electronic certificate to the server 30 (step S108). The control unit 31 of the server 30 registers the received electronic certificate in the storage unit 32 as an electronic certificate (L2 in FIG. 7) in the information related to the removable recording medium 10 (step S109).

  The certificate authority server 90 also sends the issued electronic certificate of the removable recording medium 10 to the computer 20 (step S110).

  The control unit 21 of the computer 20 recognizes that the electronic certificate received via the communication unit 24 belongs to the removable recording medium 10. The control unit 21 stores the received electronic certificate in the storage unit 22 of the computer 20 and sends the electronic certificate to the removable recording medium 10 (step S111).

  The control unit 11 of the removable recording medium 10 stores the electronic certificate received from the computer 20 as the electronic certificate 145 in the control information storage unit 14 (step S112).

  On the other hand, the control unit 31 of the server 30 registers a digital certificate of the removable recording medium 10 in the storage unit 32 (step S109), and then creates a new password for the removable recording medium 10 to encrypt data. Then, the created password is registered in the storage unit 32 as a password (L5 in FIG. 7) in the information related to the removable recording medium 10 (step S120). Here, the method of creating a password by the control unit 31 may be any method. For example, by generating a random number and determining the character, number, symbol, etc. of each digit of the password, the desired number of digits It is possible to create a password. Alternatively, a plurality of word dictionaries are provided, a plurality of words are selected from each dictionary by generating a random number, and a combination of the selected words (for example, a combination of the word “XXX” and the word “ΔΔΔ”) is selected. A password may be used.

  In addition, the control unit 31 creates an initialization password and an unbreakable password for the removable recording medium 10, and an initialization password (L 6 in FIG. 7) in the information related to the removable recording medium 10 and the unbreakable decryption. A password (L7 in FIG. 7) is registered in the storage unit 32 (step S121).

  Next, the control unit 31 of the server 30 creates an e-mail to be transmitted to the computer 20.

  That is, the control unit 31 uses the received password (L4 in FIG. 7) in addition to the created password (L5 in FIG. 7), the initialization password (L6 in FIG. 7), and the password that cannot be decrypted (L7 in FIG. 7). Create the e-mail body that is listed. Next, an electronic certificate (L2 in FIG. 7) is attached to the body of the electronic mail, and an electronic mail in S / MIME format with an electronic signature added thereto is created. And the control part 31 transmits the produced e-mail toward the computer 20 (step S122).

  The control unit 21 of the computer 20 confirms whether the electronic mail received via the communication unit 24 has been received from the legitimate server 30 without alteration. That is, the control unit 21 confirms the electronic signature added to the e-mail and confirms that the e-mail text and the electronic certificate have not been tampered with. Further, the validity of the electronic certificate is confirmed by comparing the electronic certificate attached to the body of the electronic mail with the electronic certificate stored in the storage unit 22, and the validity of the server 30 on the e-mail transmission side is confirmed. Check.

  When the validity of the e-mail is confirmed, the control unit 21 sends the password, the initialization password, and the unencryptable password described in the e-mail to the removable recording medium 10 (step) S123). The control unit 11 of the detachable recording medium 10 receives the password, initialization password, and unencryptable password received from the computer 20 in the control information storage unit 14, respectively. The password 143 is saved (step S124). When the control unit 21 of the computer 20 cannot confirm the validity of the e-mail received from the server 30, the control unit 21 discards the e-mail.

  Next, an operation for registering the telephone number of the portable terminal 40 in the information related to the removable recording medium 10 in the server 30 will be described with reference to FIG.

  FIG. 6 is a second sequence diagram illustrating an operation of registering information relating to the removable recording medium of the second embodiment in the server.

  First, a call is made from the mobile terminal 40 to the voice response device 70 (step S201 in FIG. 6).

  When receiving the incoming call from the mobile terminal 40, the control unit 71 of the voice response device 70 acquires the telephone number of the mobile terminal 40 from the caller telephone number. Then, the control unit 71 instructs the voice response unit 72 to play voice guidance on the portable terminal 40. The voice response unit 72 provides voice guidance to the portable terminal 40 so as to transmit a processing request instructed by the portable terminal 40 (step S202).

  The user of the portable terminal 40 who has heard the voice guidance instructs a new registration process as a process request (step S203). This instruction is performed by uttering voice to the mouthpiece of the mobile terminal 40 or by pressing an operation button on the mobile terminal 40.

  The voice recognition unit 73 of the voice response device 70 recognizes the processing request (new registration processing) instructed from the mobile terminal 40, converts the recognized processing request (new registration processing) into text, and sends the text to the control unit 71. To do. The recognition here is performed by the voice recognition function of the voice recognition unit 73 when an instruction from the portable terminal 40 is given by voice. When an instruction from the mobile terminal 40 is issued by pressing an operation button on the mobile terminal 40, the recognition here is performed by determining the type of the pressed operation button, for example, from the frequency.

  Next, the control unit 71 of the voice response device 70 instructs the voice response unit 72 to play voice guidance for allowing the portable terminal 40 to input the serial number of the removable recording medium 10. The voice response unit 72 provides voice guidance to the portable terminal 40 so that the serial number of the removable recording medium 10 is input and transmitted (step S204).

  The user of the portable terminal 40 who has heard the voice guidance inputs the serial number of the removable recording medium 10 and transmits it to the voice response device 70 (step S205). This input is also performed by uttering voice to the mouthpiece of the portable terminal 40 or by pressing an operation button on the portable terminal 40.

  The voice recognition unit 73 of the voice response device 70 recognizes the manufacturing number transmitted from the portable terminal 40, converts the recognized manufacturing number into text, and sends the text to the control unit 71. The recognition here is also performed by the voice recognition function of the voice recognition unit 73 when the input from the portable terminal 40 is performed by voice. When the input from the portable terminal 40 is performed by pressing the operation button of the portable terminal 40, the recognition here is performed by determining the type of the pressed operation button, for example, from the frequency.

  The control unit 71 of the voice response device 70 sends the telephone number of the portable terminal 40, the processing request (new registration process) instructed from the portable terminal 40, and the serial number of the removable recording medium 10 to the server 30. The data is transmitted via the LAN 80 (step S206).

  Since the processing request received from the voice response device 70 is a new registration process, the control unit 31 of the server 30 is currently in the process of registering information about the removable recording medium 10 in the server 30. Recognize that. Therefore, the control unit 31 searches whether the serial number of the removable recording medium 10 received from the voice response device 70 is registered as information regarding the removable recording medium 10 in the storage unit 32. When the production number is registered as information relating to the removable recording medium 10, the telephone number of the portable terminal 40 received from the voice response device 70 is used as the telephone number in the information relating to the removable recording medium 10 (L3 in FIG. 7). ) In the storage unit 32 (step S207). If the production number is not registered as information about the removable recording medium 10, it is assumed that some trouble has occurred, and the control unit 31 ends the operation.

  After registering the telephone number of the portable terminal 40 as information relating to the removable recording medium 10 (step S207), the control unit 31 of the server 30 responds with a message indicating that registration of information relating to the removable recording medium 10 is complete. The data is sent to the device 70 (step S208).

  The control unit 71 of the voice response device 70 causes the voice response unit 72 to perform voice guidance to the effect that registration of information related to the removable recording medium 10 has been completed (step S209), and is connected to the portable terminal 40. Hang up the phone.

  By performing the operations of FIGS. 5 and 6 described above, the registration of the information about the removable recording medium 10 to the server 30 is completed. When the registration is completed, the storage unit 32 of the server 30 stores information regarding the removable recording medium 10 as shown in FIG. 7, such as a manufacturing number, an electronic certificate, a telephone number, a received password, a password, and an initialization. Registered as a password and a password that cannot be decrypted. Further, the password 141, the initialization password 142, the unencryptable password 143, and the electronic certificate 145 are also registered in the control information storage unit 14 of the removable recording medium 10.

  Next, with reference to FIG. 8, the operation of the present embodiment when the removable recording medium 10 attached to the computer 20 is removed will be described.

  FIG. 8 is a sequence diagram for explaining the operation when the removable recording medium is removed from the computer.

  The removable recording medium 10 attached to the computer 20 is removed from the computer 20 (step S301 in FIG. 8).

  Then, the connection unit 16 of the detachable recording medium 10 sends a signal indicating that the detachable recording medium 10 has been removed from the computer 20 to the detachment detection unit 17. The attachment / detachment detection unit 17 sends a detection signal indicating that the removable recording medium 10 has been removed from the computer 20 to the control unit 11.

  Upon receiving this detection signal, the control unit 11 instructs the encryption setting / cancellation unit 12 to encrypt the data in the storage unit 13. The encryption setting / cancellation unit 12 reads the password 141 in the control information storage unit 14, and encrypts data in the storage unit 13 using the password 141 as a key for encryption (step S302).

  As described above, since the data in the storage unit 13 is encrypted when the removable recording medium 10 is detached from the computer 20, the data in the storage unit 13 of the removable recording medium 10 is transferred to the plaintext by another computer or the like. It is impossible to read as it is.

  Next, the operation of this embodiment when the removable recording medium 10 is remounted on the computer 20 will be described with reference to FIG.

  FIG. 9 is a sequence diagram for explaining the operation when the removable recording medium is reattached to the computer.

  First, the removable recording medium 10 is mounted on the computer 20 (step S401 in FIG. 9).

  Then, the connection unit 16 of the detachable recording medium 10 sends a signal indicating that the detachable recording medium 10 is connected to the computer 20 to the detachment detection unit 17. The attachment / detachment detection unit 17 sends a detection signal indicating that the removable recording medium 10 is attached to the computer 20 to the control unit 11.

  Upon receiving this detection signal, the control unit 11 starts an operation based on a program that realizes its own function stored in the storage unit 18. Then, the control unit 11 reads a removable recording medium control program to be executed by the computer 20 from the storage unit 18 and sends the program to the computer 20. Receiving the program, the computer 20 starts the operation by interrupting the program that has been operating until then.

  Next, the control unit 11 reads the production number 151 stored in the production number storage unit 15, and the password 141 and the electronic certificate 145 stored in the control information storage unit 14 (step S402). Then, the control unit 11 sends the serial number 151, the password 141, and the electronic certificate 145 to the computer 20 (step S403).

  The control unit 21 of the computer 20 first compares the electronic certificate 145 received from the removable recording medium 10 with the electronic certificate stored in the storage unit 22 of the computer 20. If the two electronic certificates do not match, the correctness of the removable recording medium 10 cannot be recognized, and the control unit 21 performs error processing. The error processing here is, for example, to re-send the electronic certificate 145 from the removable recording medium 10, or to end the operation of the control unit 21.

  If the two electronic certificates match, the validity of the removable recording medium has been confirmed, and the control unit 21 generates an e-mail text describing the serial number 151 and the password 141 received from the removable recording medium 10. . Next, the control unit 21 attaches the electronic certificate stored in the storage unit 22 to the electronic mail text, and creates an S / MIME format electronic mail with an electronic signature added thereto. And the control part 21 transmits the said email toward the server 30 via the communication part 24 (step S404).

  In the server 30 that has received the electronic mail from the computer 20, the control unit 31 first checks whether the received electronic mail has been received from the legitimate computer 20 without alteration. That is, the control unit 31 confirms the electronic signature added to the e-mail and confirms that the e-mail body and the electronic certificate have not been tampered with. Further, the validity of the electronic certificate is compared by comparing the electronic certificate attached to the body of the electronic mail with the electronic certificate (L2 in FIG. 7) in the information related to the removable recording medium 10 in the storage unit 32. And the validity of the computer 20 on the e-mail transmission side is confirmed. Further, when the password described in the e-mail text is the same as the password (L5 in FIG. 7) in the information relating to the removable recording medium 10 in the storage unit 32, the received e-mail is valid. It is recognized that the message was received from the computer 20 without alteration. When the control unit 31 recognizes that the e-mail is not valid, the control unit 31 discards the e-mail.

  Further, when the validity of the e-mail is confirmed, the control unit 31 uses the password described in the e-mail as the reception password for information regarding the removable recording medium 10 in the storage unit 32 (see FIG. 7). L4) is registered (step S405). Further, the control unit 31 searches for and extracts a telephone number (L3 in FIG. 7) from information on the removable recording medium 10 in the storage unit 32 based on the manufacturing number described in the e-mail (step S406). ).

  Then, the control unit 31 of the server 30 makes a call through the gateway 60 to the mobile terminal 40 having the telephone number searched in Step S406 (Step S407). The control unit 61 of the gateway 60 instructs the call connection unit 62 to make a call connection to the portable terminal 40 instructed by the server 30, and the call connection unit 62 makes a call connection to the portable terminal 40 (step S408). When the mobile terminal 40 receives a response signal indicating that it has responded to the call connection, the gateway 60 sends this response signal to the server 30.

  Further, the control unit 31 of the server 30 makes a call to the voice response device 70 via the gateway 60 (step S409). The control unit 61 of the gateway 60 instructs the call connection unit 62 to make a call connection to the voice response device 70 instructed by the server 30, and the call connection unit 62 makes a call connection to the voice response device 70 (step S410). ). When the response signal indicating that the voice response device 70 has responded to the call connection is received, the gateway 60 transmits this response signal to the server 30.

  When response signals from the mobile terminal 40 and the voice response device 70 reach the server 30 via the gateway 60, the control unit 31 of the server 30 connects the gateway 60 to the gateway 60 so as to call-connect the mobile terminal 40 and the voice response device 70. An instruction is issued (step S411).

  The control unit 61 of the gateway 60 instructs the call connection unit 62 to make a call connection between the portable terminal 40 and the voice response device 70, and the call connection unit 62 makes a call connection between the portable terminal 40 and the voice response device 70. Thereby, the portable terminal 40 and the voice response device 70 are in a state in which a call can be made (step S412).

  First, the control unit 71 of the voice response device 70 in a state in which a call can be made with the portable terminal 40 acquires the telephone number of the portable terminal 40. Then, the control unit 71 instructs the voice response unit 72 to play voice guidance on the portable terminal 40. The voice response unit 72 provides voice guidance to the portable terminal 40 so as to transmit a processing request instructed by the portable terminal 40 (step S420).

  The user of the portable terminal 40 who has heard the voice guidance instructs the decryption process as a processing request (step S421). This instruction is performed by uttering voice to the mouthpiece of the mobile terminal 40 or by pressing an operation button on the mobile terminal 40. The descrambling process means a process of decrypting the encrypted data in the storage unit 13 of the removable recording medium 10 when the removable recording medium 10 is reattached to the computer 20.

  The voice recognition unit 73 of the voice response device 70 recognizes a processing request (decryption processing) instructed from the portable terminal 40, converts the recognized processing request (decryption processing) into text, and controls the control unit 71. To send. The recognition here is performed by the voice recognition function of the voice recognition unit 73 when an instruction from the portable terminal 40 is given by voice. When an instruction from the mobile terminal 40 is issued by pressing an operation button on the mobile terminal 40, the recognition here is performed by determining the type of the pressed operation button, for example, from the frequency.

  Next, the control unit 71 of the voice response device 70 instructs the voice response unit 72 to play voice guidance indicating that the processing request has been received in the portable terminal 40. The voice response unit 72 provides voice guidance indicating that the processing request has been accepted. Then, the voice response device 70 disconnects the telephone connected to the mobile terminal 40 (step S422).

  Then, the control unit 71 of the voice response device 70 sends the telephone number of the mobile terminal 40 and the processing request (encryption release processing) instructed by the mobile terminal 40 to the server 30 via the LAN 80 (step). S423).

  Since the processing request received from the voice response device 70 is the descrambling process, the control unit 31 of the server 30 is currently reattached to the computer 20 and the removable recording medium 10 Recognize that the data is in a state before being decoded. Therefore, the control unit 31 again creates a password for the removable recording medium 10 to encrypt the data, and stores the created password as a password (L5 in FIG. 7) in the information related to the removable recording medium 10. Register in the unit 32 (step S424). In the present embodiment, every time the removable recording medium 10 is reconnected to the computer 20, a password for the removable recording medium 10 to encrypt data is recreated by the server 30, and the computer 20 To send to.

  Next, the control unit 31 of the server 30 creates an e-mail to be transmitted to the computer 20.

  That is, the control unit 31 creates an e-mail text that describes the received password (L4 in FIG. 7) in addition to the created password (L5 in FIG. 7). Next, an electronic certificate (L2 in FIG. 7) is attached to the body of the electronic mail, and an electronic mail in S / MIME format with an electronic signature added thereto is created. And the control part 31 transmits the produced email to the computer 20 (step S425).

  The control unit 21 of the computer 20 confirms whether the electronic mail received via the communication unit 24 has been received from the legitimate server 30 without alteration. That is, the control unit 21 confirms the electronic signature added to the e-mail and confirms that the e-mail text and the electronic certificate have not been tampered with. Further, the validity of the electronic certificate is confirmed by comparing the electronic certificate attached to the body of the electronic mail with the electronic certificate stored in the storage unit 22, and the validity of the server 30 on the e-mail transmission side is confirmed. Check sex.

  When the validity of the e-mail is confirmed, the control unit 21 sends the password described in the e-mail and the received password to the removable recording medium 10 (step S426). This sending is executed based on the aforementioned program received from the removable recording medium 10.

  The connection unit 16 of the detachable recording medium 10 sends the password received from the computer 20 and the received password to the control unit 11.

  The control unit 11 instructs the encryption setting / cancellation unit 12 to decrypt the encrypted data in the storage unit 13 using the received password (that is, the same password 141 read in step S402 in FIG. 9). . The encryption setting / cancellation unit 12 performs a process of decrypting the data in the storage unit 13 using the received password and returning it to plaintext data (step S427).

  Next, the control unit 11 stores the password received from the computer 20 as the password 141 in the control information storage unit 14 (step S428).

  Then, the control unit 11 of the removable recording medium 10 notifies the computer 20 that the encrypted data in the storage unit 13 has been decrypted. Receiving this notification, the computer 20 ends the operation of the removable recording medium control program received from the removable recording medium 10 and returns to the operation of the computer 20 by the program. As described above, the computer 20 can access the removable recording medium 10.

  Next, the initialization password (L6 in FIG. 7) and the unencryptable password (L7 in FIG. 7) described in FIG. 7 will be described.

  First, the initialization password will be described.

  The initialization password is a password for initializing the removable recording medium 10.

  For example, as shown as step S424 in FIG. 9, when the removable recording medium 10 is reattached to the computer 20, the server 30 recreates a password for encryption, and sends the computer 20 by email. To send to. The removable recording medium 10 decrypts the encrypted data in the storage unit 13 using the received password sent from the computer 20 (see step S427 in FIG. 9).

  Here, if the e-mail does not reach the computer 20 for some reason, the removable recording medium 10 cannot obtain the received password, and thus the encrypted data in the storage unit 13 cannot be decrypted. When such a situation occurs, the removable recording medium 10 is initialized using the initialization password.

  That is, in order to initialize the removable recording medium 10, first, the removable recording medium 10 is reattached to the computer 20. Then, the server 30 receives an electronic mail from the computer 20 (see step S404 in FIG. 9), and then performs voice guidance to transmit a processing request to the portable terminal 40 via the voice response device 70 (see FIG. 9). (See step S420 in FIG. 9).

  Here, the user of the portable terminal 40 who has heard this voice guidance instructs an initialization process as a processing request. That is, in step S421 in FIG. 9, the decryption processing instruction is issued as a processing request, but an initialization processing instruction is issued instead of the decryption processing. Then, in step S423 in FIG. 9, an initialization process is sent to the server 30 as a process request.

  The server 30 that has received the initialization process as the process request extracts the initialization password (L6 in FIG. 7) from the information related to the removable recording medium 10, and sends the electronic mail describing the initialization password to the computer 20. Send.

  The computer 20 that has received the e-mail describing the initialization password sends the initialization password to the removable recording medium 10. The removable recording medium 10 that has received the initialization password decrypts the encrypted data in the storage unit 13 using the password 141 in the control information storage unit 14. The password 141 used here is the password 141 read in step S <b> 402 in FIG. 9, and is the password 141 used when encrypting data in the storage unit 13. Therefore, it is possible to decrypt the encrypted data in the storage unit 13.

  Then, the removable recording medium 10 clears all of the password 141, the initialization password 142, the unencryptable password 143, and the electronic certificate 145 in the control information storage unit 14 (that is, writes a null string). Thereby, the removable recording medium 10 can be returned to the initial state.

  Next, a password that cannot be decrypted will be described.

  The unencryptable password is a password for making it impossible to decrypt the data on the removable recording medium 10.

  For example, the removable recording medium 10 is lost, and a person who has found the removable recording medium 10 tries to use the removable recording medium 10 by attaching the removable recording medium 10 to a computer owned by the person who has found the removable recording medium 10. Shall.

  Then, an electronic mail is transmitted from the computer on which the removable recording medium 10 is mounted to the server 30 (see step S404 in FIG. 9). Subsequently, the server 30 sends the message to the portable terminal 40 via the voice response device 70. Voice guidance is performed to transmit the processing request (see step S420 in FIG. 9). Since this portable terminal 40 belongs to a user who has lost the removable recording medium 10, the lost user knows that the removable recording medium 10 that he / she owns is about to be used by another person. Become.

  Here, the user of the portable terminal 40 who has heard this voice guidance instructs the decryption impossible processing as a processing request. That is, in step S421 in FIG. 9, the decryption processing instruction is issued as the processing request, but instead of this decryption processing, the decryption impossible processing instruction is issued. Then, in step S423 in FIG. 9, the decryption impossible process is sent to the server 30 as a process request.

  The server 30 that has received the decryption impossible process as the processing request extracts the password that cannot be decrypted (L7 in FIG. 7) from the information related to the removable recording medium 10, and an email that describes the password that cannot be decrypted To the computer.

  Then, the computer sends an unencryptable password to the removable recording medium 10. The removable recording medium 10 that has received the password that cannot be decrypted from the computer recognizes that it has been instructed not to decrypt the encrypted data in the storage unit 13 thereafter. Then, for example, the control unit 11 of the detachable recording medium 10 sets a register that disables decryption, and thereafter operates so as not to decrypt the encrypted data in the storage unit 13 no matter what data is received. To do. As a result, the data in the storage unit 13 in the removable recording medium 10 cannot be returned to plain text data.

  The second embodiment of the password setting method for the removable recording medium according to the present invention has been described above.

  As described above, the password setting method of the removable recording medium according to the present embodiment includes the storage unit 13 that stores data, the control information storage unit 14 that stores the password 141 for encryption, and the data encryption. A removable recording medium 10 including a control unit 11 that performs operation control is included. Further, the computer 20 includes a computer 20 on which the removable recording medium 10 can be mounted, and a server 30 that communicates with the computer 20. Furthermore, a mobile terminal 40 that is connected to the server 30 for communication is included.

  When the detachable recording medium 10 is attached to the computer 20, the control unit 11 of the detachable recording medium 10 transmits the password 141 to the server 30 via the computer 20. When the server 30 that has received the password 141 (reception password) receives a decryption processing request from the portable terminal 40, the server 30 creates a new password that substitutes for the reception password. Then, the server 30 sends the new password and the received password to the computer 20, and the computer 20 sends the new password and the received password to the removable recording medium 10. Upon receiving the new password and the received password, the control unit 11 of the removable recording medium 10 decrypts the data using the received received password, and changes the password 141 stored in the control information storage unit 14 to the new password. To do. Specifically, the new password is stored in the control information storage unit 14 instead of the password 141.

  That is, the server 30 creates a new password each time the removable recording medium 10 is loaded into the computer 20 and sends the new password to the removable recording medium 10. The removable recording medium 10 replaces the original password 141 with a new password.

  Therefore, according to the present embodiment, it is possible to prevent the data on the removable recording medium from leaking to anyone other than the user and to update the password safely without storing and inputting the password by the user.

  Further, when the removable recording medium 10 is removed from the computer 20, the control unit 11 of the removable recording medium 10 uses the password 141 stored in the control information storage unit 14 to encrypt data. ing.

  Therefore, according to the present embodiment, it is possible to protect data on a removable recording medium, and data leakage is eliminated.

  Further, when the server 30 that has received the password 141 receives a request for the initialization process from the portable terminal 40, the server 30 transmits the initialization password to the computer 20, and the computer 20 records the initialization password in a removable manner. Send to medium 10. Upon receiving the initialization password, the control unit 11 of the removable recording medium 10 decrypts the data using the password 141 stored in the control information storage unit 14 and clears the password in the control information storage unit 14. The removable recording medium 10 is initialized.

  Therefore, according to the present embodiment, even when the password of the control information storage unit of the removable recording medium is cleared and the removable recording medium is initialized, the data in the storage unit is not destroyed. The stored data is stored in the removable recording medium.

  In addition, when the server 30 that has received the password 141 receives a processing request for unencryptable processing from the portable terminal 40, the server 30 transmits the unencryptable password to the computer 20, and the computer 20 decrypts the decryption. The impossible password is sent to the removable recording medium 10. The control unit 11 of the detachable recording medium 10 operates so as not to decrypt data upon receipt of the password that cannot be decrypted.

  Therefore, according to this embodiment, it is impossible to read the data on the removable recording medium with another person's computer.

  Further, communication between the computer 20 and the server 30 is performed using encrypted electronic mail.

  Therefore, according to this embodiment, there is no leakage of passwords transmitted and received between the computer and the server.

DESCRIPTION OF SYMBOLS 10 Removable recording medium 11 Control part 12 Encryption setting / cancellation part 13 Storage part 14 Control information storage part 141 Password 142 Initialization password 143 Unencryptable password 145 Electronic certificate 15 Serial number storage part 151 Serial number 16 Connection part 17 Attachment / detachment detection unit 18 Storage unit 19 Control unit 20 Computer 21 Control unit 22 Storage unit 23 Connection unit 24 Communication unit 25 Operation unit 26 Display unit 30 Server 31 Control unit 32 Storage unit 40 Portable terminal 50 Communication network 60 Gateway 61 Control unit 62 Call Connection unit 70 Voice response device 71 Control unit 72 Voice response unit 73 Voice recognition unit 80 LAN
90 Certificate Authority server

Claims (20)

A detachable recording medium including a first storage unit that stores data, a second storage unit that stores a password for encryption, and a control unit that performs operation control including encryption of the data;
A computer to which the removable recording medium can be mounted;
A server in communication connection with the computer;
A mobile terminal for communication connection with the server;
Including
When the removable recording medium is attached to the computer, the control unit of the removable recording medium causes the password to be transmitted to the server via the computer,
When the server that has received the password receives a decryption processing request from the mobile terminal, the server creates a new password that replaces the password, and transmits the new password and the password to the computer. And the computer sends the new password and the password to the removable recording medium,
The control unit of the detachable recording medium decrypts the data using the received password and receives the password stored in the second storage unit upon receipt of the new password and the password. Change to a new password,
Password setting method for removable recording media. When the removable recording medium is removed from the computer, the control unit of the removable recording medium encrypts the data using the password stored in the second storage unit.
The password setting method for a removable recording medium according to claim 1. When the server that has received the password receives a processing request for initialization processing from the mobile terminal,
The server sends an initialization password to the computer, and the computer sends the initialization password to the removable recording medium,
Upon receipt of the initialization password, the control unit of the removable recording medium decrypts the data using the password stored in the second storage unit, and the password of the second storage unit To initialize the removable recording medium,
The password setting method for a removable recording medium according to claim 1. When the server that has received the password receives a processing request for unencryptable processing from the mobile terminal,
The server sends a password that cannot be decrypted to the computer, and the computer sends the password that cannot be decrypted to the removable recording medium,
The control unit of the removable recording medium operates so as not to decrypt the data upon receipt of the unencryptable password.
The password setting method for a removable recording medium according to claim 1. Communication between the computer and the server is performed using encrypted email.
The password setting method for a removable recording medium according to any one of claims 1 to 4. In a password setting method for a removable recording medium that stores data and a password for encryption,
When the removable recording medium is attached to a computer, the password stored in the removable recording medium is transmitted to a server,
Based on the decryption processing request, the server creates a new password to replace the password, and sends the new password and the password to the removable recording medium,
Decrypting the data using the password received by the removable recording medium and changing the password stored in the removable recording medium to the new password;
Password setting method for removable recording media. When the removable recording medium is removed from the computer, the data is encrypted using the password.
The password setting method for a removable recording medium according to claim 6. Based on the processing request for initialization processing, the server sends an initialization password to the removable recording medium,
Decrypting the data using the password with the removable recording medium, clearing the password and initializing;
The password setting method for a removable recording medium according to claim 6. Based on the processing request for decryption disable processing, the server sends a password that cannot be decrypted to the removable recording medium,
Receiving the unencryptable password by the removable recording medium so as not to decrypt the data;
The password setting method for a removable recording medium according to claim 6. Communication between the computer and the server is performed using encrypted email.
10. The method for setting a password for a removable recording medium according to claim 6, wherein the password is set. A removable recording medium for storing data and a password for encryption,
When the removable recording medium is attached to a computer, the password is transmitted to the server via the computer, and when the new password and the password are received from the server, the data is decrypted using the received password. And a control unit that changes the password to the new password.
Removable recording medium. When the removable recording medium is removed from the computer, the control unit encrypts the data using the password.
The detachable recording medium according to claim 11. The control unit receives the initialization password from the server, decrypts the data using the password, clears the password, and initializes the removable recording medium.
The detachable recording medium according to claim 11. When the control unit receives a password that cannot be decrypted from the server, the control unit operates so as not to decrypt the data.
The detachable recording medium according to claim 11. A server capable of communication connection with a computer and a portable terminal,
When a password of a removable recording medium attached to the computer is received and a decryption request is received from the mobile terminal, a new password is created as an alternative to the password, and the new password and the password are Including a control unit for transmitting to the computer,
server. The control unit, when receiving a processing request for initialization processing from the mobile terminal, transmits an initialization password to the computer.
The server according to claim 15. The control unit, when receiving a processing request for unencryptable processing from the mobile terminal, transmits an unencryptable password to the computer.
The server according to claim 15. Communication with the computer is performed using encrypted email,
The server according to any one of claims 15 to 17, characterized by: A password recording method for a removable recording medium for storing a password,
In response to attachment of the removable recording medium to the computer, a new password request including the password is sent,
When the new password and the password are received as a response to the new password request, the password is changed to the new password.
A password recording method for a removable recording medium. A new password setting method in the server,
When a new password request including a password is received, a new password as a substitute for the password is created based on the decryption processing request, and the new password and the password are sent as a response to the new password request ,
New password setting method on the server.

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