JP6294203B2 - Authentication system - Google Patents

Description

  The present invention relates to an authentication system for authenticating transaction contents when performing transactions such as remittance using the Internet.

  In a system for performing transactions such as remittance using the Internet, in addition to the ID assigned to the user, the principal is confirmed by a password known only to the principal and a trading partner such as a financial institution. As a result, fraudulent remittance from a user's account by impersonation is prevented.

Further, as a recent technical trend, a method of performing identity verification and transaction content authentication using a temporary password (time-synchronized one-time password) determined by time has become widespread. In this method, a user has a device that generates a time-synchronized one-time password, and the time-synchronized one-time password is also generated on the authentication server side. Then, the authentication server verifies the time-synchronized one-time password input / transmitted by the user.
This method is an effective means for preventing spoofing performed by illegally obtaining a repeatedly used password by interception and analysis of communication. However, it cannot prevent a “man-in-the-middle attack” in which a user is guided to a fake site and spoofed using a legitimate time-synchronized one-time password entered at the fake site.

Therefore, Patent Literature 1 generates a transaction content authentication one-time password for each transaction by an authentication server, transmits the transaction content authentication one-time password and transaction information indicating the transaction content to a portable information terminal, and Disclosed is an authentication system that allows a service user to input a one-time password for transaction details authentication from a terminal that receives an online service after confirmation of the transaction details. According to the technology described in Patent Document 1, a user detects a man-in-the-middle attack by confirming the transaction content, and does not approve the transaction by not entering or replying to a one-time password to prevent unauthorized remittance. be able to.
Non-Patent Document 1 includes a USB interface and an audio interface, and when performing transactions in an online banking service or the like, the user is permitted or rejected by pressing a button after confirming the transaction details on the screen. A terminal (UniMate Flex) to be selected is described. According to the technology described in Non-Patent Document 1, when a user detects a man-in-the-middle attack by checking transaction details, and detects a man-in-the-middle attack, the user does not press the button on the device to conduct the transaction. Unauthorized payments can be prevented.

JP 2007-249726 A

UniMate Flex. [Online]. SecuTech. [Retrieved on 2014-09-05]. Retrieved from the Internet: <URL: http://esecutech.com/old/en/Mobile Authentication / unimateflex / unimate-flex-Product Overview .html>.

From 2013 to 2014, fraudulent remittances for online banking have increased rapidly, and the risk of attacks called man-in-the-middle attacks has also increased.
On the other hand, as described in Patent Document 1, as a countermeasure against man-in-the-middle attacks, when using the personal information terminal such as a mobile phone or a smart phone, the transaction contents and the one-time password are used when performing Internet transactions on a personal computer. There are known ways to tell people.

However, with the widespread use of mobile phones and smartphones, the need to use mobile phones and smartphones for payments instead of PCs is increasing, and it is assumed that PCs + mobile phones, PCs + smartphones, or PCs + landlines The number of cases that cannot be increased. That is, the case where the method of patent document 1 cannot be applied is increasing.
In addition, the smartphone may be infected with malware that performs malicious operations not intended by the user, and the malware may authenticate unauthorized transactions. That is, it is considered that the method of Non-Patent Document 1 is insufficient as a countermeasure against fraudulent transactions caused by malware.

  An object of the present invention is to provide an authentication system having safety that can withstand unauthorized transactions due to man-in-the-middle attacks, malware infection of a portable information terminal, and hijacking on the condition that only the portable information terminal communicates with a server.

In order to solve the above problems, the authentication system of the present invention provides:
An authentication system having a transaction business server, a transaction authentication strengthening server, a portable information terminal, and a password display dedicated machine,
The transaction server is
A transaction authentication requesting means for generating a transaction information including the transaction content and transmitting a transaction authentication request including the transaction information to the transaction authentication strengthening server upon receiving a transaction operation request including the transaction content from the portable information terminal; ,
When the one-time password is received from the portable information terminal, the one-time password is transmitted to the transaction authentication strengthening server, and when the authentication success is notified from the transaction authentication strengthening server, the transaction business is performed according to the transaction content. Means,
With
The transaction authentication strengthening server is
When receiving a transaction authentication request from the transaction business server, a one-time password generating means for generating a one-time password;
Voice data transmitting means for converting the one-time password and transaction information generated by the one-time password generating means into voice data and transmitting the voice data to the portable information terminal;
When the one-time password is received from the transaction business server, the received one-time password is compared with the one-time password generated by the one-time password generation means to determine whether or not the authentication is successful. An authentication means for notifying the transaction server of successful authentication when successful,
With
The portable information terminal is
Transaction content accepting means for accepting the transaction content entered by the user;
Transaction information transmitting means for transmitting a transaction business request including the transaction content received by the transaction content reception means to the transaction business server;
Voice receiving means for receiving the voice data from the transaction authentication strengthening server;
Voice output means for converting voice data received by the voice receiving means into sound and outputting the sound;
One-time password accepting means for accepting a one-time password input by the user;
One-time password transmission means for transmitting the one-time password accepted by the one-time password acceptance means to the transaction business server;
With
The dedicated password display machine
Voice input means for inputting sound output by the portable information terminal;
Information extraction means for extracting one-time password and transaction information from information included in the sound input by the voice input means;
Display means for displaying the one-time password extracted by the information extraction means and part or all of the extracted transaction information;
Comprising
It is characterized by that.

Preferably, the authentication system of the present invention comprises:
The transaction content includes mobile information terminal specifying information for specifying a mobile information terminal,
The transaction authentication strengthening server comprises a phone number table including the mobile information terminal specifying information and a phone number of the mobile information terminal specified by the mobile information terminal specifying information,
The voice data transmitting means of the transaction authentication strengthening server acquires a telephone number corresponding to the portable information terminal specifying information included in the transaction contents from the telephone number table, and makes a call to the acquired telephone number, and performs telephone communication. Sending the voice data over the network,
Voice receiving means of the portable information terminal receives voice data transmitted via the telephone communication network;
It is characterized by that.

Preferably, the authentication system of the present invention comprises:
The transaction authentication strengthening server includes an encryption unit that encrypts the one-time password generated by the one-time password generation unit and the transaction information included in the transaction authentication request.
The voice data transmission means of the transaction authentication strengthening server converts the one-time password and transaction information encrypted by the encryption means into voice data, and transmits the voice data to the portable information terminal,
The information extraction unit of the password display dedicated machine extracts the encrypted one-time password and transaction information from information included in the sound input by the voice input unit, and the encrypted one-time password and transaction Decrypt information,
It is characterized by that.

Preferably, the authentication system of the present invention comprises:
The transaction authentication strengthening server designates a plurality of encryption keys that can be used to encrypt the one-time password and the transaction information, and an encryption key that is used to encrypt the plurality of encryption keys. A first encryption key table having encryption key designation information to be
The encryption means of the transaction authentication strengthening server acquires an encryption key specified by the encryption key specification information acquired by a predetermined method from the first encryption key table, and uses the acquired encryption key to Encrypt one-time password and transaction information,
The voice data transmission means of the transaction authentication strengthening server specifies the encryption key used to encrypt the one-time password and transaction information in addition to the one-time password and transaction information encrypted by the encryption means. The encryption key designation information to be converted into voice data, the voice data is transmitted to the portable information terminal,
The password display dedicated machine includes a second encryption key table having the plurality of encryption keys and the encryption key designation information;
The information extraction unit of the password display dedicated machine extracts the encrypted one-time password and transaction information and the encryption key designation information from information included in the sound input by the voice input unit, and the encryption key Obtaining an encryption key designated by the designated information from the second encryption key table, and decrypting the encrypted one-time password and transaction information using the obtained encryption key;
It is characterized by that.

Preferably, the authentication system of the present invention comprises:
The transaction authentication strengthening server comprises encryption key storage means for encryption key specification information for storing an encryption key for encrypting the encryption key specification information,
The encryption means of the transaction authentication strengthening server encrypts the encryption key designation information using the encryption key stored in the encryption key designation information encryption key storage means;
The voice data transmission means of the transaction authentication strengthening server converts the encryption key designation information encrypted in addition to the one-time password and the transaction information encrypted by the encryption means into voice data, Send to the mobile information terminal,
The password display-dedicated machine comprises encryption key designation information decryption key storage means for storing a decryption key corresponding to the encryption key stored by the encryption key designation information encryption key storage means of the transaction authentication strengthening server;
The information extraction means of the password display dedicated machine extracts the encrypted one-time password and transaction information and the encrypted encryption key designation information from information included in the sound input by the voice input means. , Decrypting the encrypted encryption key designation information using the decryption key stored in the encryption key designation information decryption key storage means, and obtaining an encryption key designated by the decrypted encryption key designation information Obtaining from the second encryption key table;
It is characterized by that.

  ADVANTAGE OF THE INVENTION According to this invention, the authentication system with the safety | security which can endure the illegal transaction by the man-in-the-middle attack, the malware infection of a portable information terminal, and hijacking on the conditions that only a portable information terminal communicates with a server can be provided.

It is a figure which shows an example of a structure of the authentication system which concerns on embodiment of this invention. It is a figure which shows an example of a structure of the telephone number table stored in the database. It is a figure which shows an example of a structure of the common key table stored in the database. It is a figure which shows an example of a structure of transaction information. It is a figure which shows an example of a structure of the common key table stored in the read-only memory of the password display dedicated machine. It is a figure which shows an example of operation of the user (user) who performs a transaction. It is a figure which shows an example of the transaction content displayed on the display part of a password display machine, and a one-time password. It is a figure which shows an example of the flow of a process of a transaction business part and an authentication reinforcement | strengthening part. It is a figure which shows an example of the flow of a process in a password display dedicated machine.

  Hereinafter, an authentication system according to an embodiment of the present invention will be described with reference to the drawings. In all the drawings for explaining the embodiments, common constituent elements are denoted by the same reference numerals, and repeated explanation is omitted.

FIG. 1 shows an example of the configuration of an authentication system 1 according to an embodiment of the present invention.
The authentication system 1 includes a transaction business server 100 and a transaction authentication strengthening server 200 managed by a financial institution that provides a transaction service, a portable information terminal 300 and a password display dedicated device 400 held by a user (user) of the transaction service, Have
The transaction business server 100 and the transaction authentication strengthening server 200 are connected to a LAN (local area network), and can transmit and receive data via the LAN. The transaction business server 100 and the portable information terminal 300 are connected to a network 500 and can transmit and receive data via the network 500. The transaction authentication strengthening server 200 and the portable information terminal 300 are connected to the telephone communication network 501 and can make a voice call. The telephone communication network 501 includes a mobile phone communication network.

The transaction business server 100 has a CPU (Central Processing Unit), a main memory composed of RAM (Random Access Memory) and the like, and a storage device composed of a hard disk and the like. The storage device of the transaction business server 1 stores a transaction business program. The function of the transaction business unit 101 is realized by the CPU of the transaction business server 1 reading and executing the transaction business program from the storage device to the main memory.
When receiving a transaction request including transaction details from portable information terminal 300, transaction transaction unit 101 creates transaction information including transaction details and transmits a transaction authentication request including the transaction information to transaction authentication strengthening server 200. . Further, when the transaction business unit 101 receives the one-time password from the portable information terminal 300, the transaction business unit 101 transmits the one-time password to the transaction authentication strengthening server 200. Follow the transaction business.
The transaction business unit 101 is an example of a transaction authentication request unit and a transaction business unit of the present invention.

  Transaction authentication strengthening server 200 also includes a CPU, a main memory, and a storage device. The storage device of the transaction authentication strengthening server 200 stores an authentication strengthening program. The functions of the authentication strengthening unit 201 and the telephone calling unit 202 are realized by the CPU of the transaction authentication strengthening server 200 reading and executing the authentication strengthening program from the storage device to the main memory.

When the user logs in to the transaction business server 100, the authentication strengthening unit 201 performs user authentication in response to a user authentication request from the transaction business unit 101, and notifies the transaction business unit 101 of the result.
Further, the authentication strengthening unit 201 performs transaction authentication in response to a transaction authentication request for each transaction from the transaction business server 100.
Specifically, when receiving the transaction authentication request from the transaction business server 100, the authentication strengthening unit 201 generates a one-time password, encrypts the transaction information and the one-time password, and passes them to the telephone transmission unit 202.
The telephone transmission unit 202 converts the encrypted transaction information and the one-time password into voice data. At that time, for example, a method of converting image data such as FAX (facsimile) into audio data is used. Then, the telephone calling unit 202 calls the telephone number of the portable information terminal 300 and sends the transaction information converted into voice data and the one-time password to the portable information terminal 300 via the telephone communication network 501.
The portable information terminal 300 sends the transaction information and a sound indicating the one-time password to the password display dedicated device 400. The password display dedicated machine 400 extracts transaction information and a one-time password from information included in the sound, and displays them on the display.
When the user inputs the one-time password to the portable information terminal 300 after confirming the transaction information, the portable information terminal 300 transmits the one-time password to the transaction business server 100 via the network 500.
When transaction business unit 101 receives the one-time password from portable information terminal 300, transaction business unit 101 transmits it to authentication strengthening unit 201. The authentication strengthening unit 201 collates the one-time password passed to the telephone transmission unit 202 with the one-time password transmitted from the transaction business unit 101 and notifies the transaction business unit 101 of the result.
The authentication strengthening unit 201 is an example of a one-time password generation unit, an authentication unit, and an encryption unit according to the present invention. Moreover, the telephone transmission part 202 is an example of the audio | voice data transmission means of this invention.

The database 210 is connected to the transaction authentication strengthening server 200. The database 210 may be configured to be stored in the storage device of the transaction authentication strengthening server 200.
The database 210 stores a telephone number table 220, a common key table 230, and a secret key 240.
The telephone number table 220 stores telephone numbers when the telephone transmission unit 202 makes a call to the portable information terminal 300.
The common key table 230 stores a common key used when the telephone transmission unit 202 encrypts transaction information and a one-time password.
The secret key 240 is a secret key for encrypting a number for identifying a common key used for encrypting transaction information and a one-time password.

The portable information terminal 300 is, for example, a mobile phone or a smartphone. The portable information terminal 300 includes a telephone communication unit 301, an audio output unit 302, an input unit 303, a display unit 304, and a data communication unit 305.
When the telephone communication unit 301 receives a call from the transaction authentication strengthening server 200 via the telephone communication network 501, the telephone communication unit 301 confirms that the incoming call is received from the transaction authentication strengthening server 200 by checking the outgoing telephone number. When the person presses the call button, the transaction information converted into voice data and the one-time password are received.
The audio output unit 302 includes a jack, a speaker, and the like for connecting to a phone plug such as an earphone or a headphone. The audio output unit 302 outputs the encrypted transaction information and the one-time password converted into sound.
The input unit 303 includes a touch panel, a keyboard, and the like. The input unit 303 receives user operations and inputs information. The input unit 303 receives, for example, transaction contents or a one-time password input by the user.
The display unit 304 includes a display and the like. The display unit 304 displays information with characters and images.
The data communication unit 305 transmits / receives data to / from the transaction business server 100 via the network 500. The data communication unit 305 transmits, for example, a transaction business request including transaction details accepted by the input unit 303 and a one-time password transmission unit to the transaction business server 100.
The telephone communication unit 301 is an example of the voice receiving unit of the present invention, the voice output unit 302 is an example of the voice output unit of the present invention, and the input unit 303 is the transaction content receiving unit and the one-time password receiving unit of the present invention. The data communication unit 305 is an example of a transaction information transmission unit and a one-time password transmission unit of the present invention.

The password display dedicated device 400 includes a voice input unit 401, an information extraction unit 402, a display unit 403, and a read only memory 410.
The audio input unit 401 includes a phone jack, a microphone, and the like. The voice input unit 401 inputs the transaction information converted into sound and the one-time password.
The information extraction unit 402 extracts encrypted transaction information and a one-time password from information included in the sound. Then, the information extraction unit 402 decrypts the transaction information and the one-time password.
The display unit 403 includes a display and the like. Display unit 402 displays a part or all of the decrypted one-time password and transaction information.
The voice input unit 401 is an example of the voice input unit of the present invention, the information extraction unit 402 is an example of the information extraction unit of the present invention, and the display unit 403 is an example of the display unit of the present invention.

The read only memory 410 stores a common key table 420 and a public key 430.
The common key table 420 stores a common key for decrypting the encrypted transaction information and the one-time password.
The public key 430 corresponds to the secret key 240. The public key 430 is a public key for decrypting a number for identifying a common key used for decryption.

In the present embodiment, the password display-only device 400 is based on the architecture of a personal computer, and is unique in that data is stored in advance in the read-only memory 410 when a product is manufactured. This is an architecture in which only functions necessary for realizing the display-only device 400 are implemented.
Specifically, each component, that is, a display unit 403, a voice input unit 401, a battery serving as a power source for operating each component, a CPU, and data to be processed by the CPU are transferred to a motherboard serving as a base for connecting each component. Is configured to connect a RAM for temporarily recording the read-only memory 410 and a read-only memory 410. The read-only memory 410 is composed of, for example, a ROM (Read Only Memory), and the contents cannot be changed after the password display-only device 400 is manufactured. In the present embodiment, the read-only memory 410 also stores an information extraction program, and the function of the information extraction unit 402 is realized by the CPU executing the information extraction program.
Note that the password display dedicated device 400 does not have a CPU and a RAM, and the function of the information extraction unit 402 may be realized by hardware.

FIG. 2 shows an example of the configuration of the telephone number table 220 stored in the database 210.
The telephone number table 220 includes fields for a transfer source account number 221 and a telephone number 222.
The transfer source account number 221 indicates the account number of the user's bank or the like who pays the transaction fee using the portable information terminal 300 during the transaction.
The telephone number 222 indicates the telephone number of the portable information terminal 300 of the user who owns the account indicated by the transfer source account number 221. The telephone number 222 is a telephone number when the telephone transmission unit 202 makes a call to the portable information terminal 300.
In addition, the transfer source account number 221 and the portable information terminal 300 used by the user who performs the transaction can be specified. The transfer source account number 221 is an example of the portable information terminal specifying information of the present invention.

FIG. 3 shows an example of the configuration of the common key table 230 stored in the database 210.
The common key table 230 includes fields for a transfer source account number 231, a key number 232, and a common key 233.
The transfer source account number 231 indicates the account number of the user's bank or the like who pays the transaction fee at the time of the transaction.
The key number 232 is a number assigned to the common key 233.
The common key 233 is a common key used for encrypting transaction information and a one-time password.
In the present embodiment, the authentication strengthening unit 201 of the transaction authentication strengthening server 200 obtains the key number 232 using a numerical value (random number) generated at random. Then, the authentication strengthening unit 201 encrypts the transaction information and the one-time password using the common key 233 uniquely determined by the two items of the transfer source account number 231 and the key number 232. Further, the authentication strengthening unit 201 encrypts the key number 232 with the secret key 240. The authentication strengthening unit 201 passes the encrypted key number 232, the transaction information, and the one-time password to the telephone transmission unit 202, and the telephone transmission unit 202 transmits them to the portable information terminal 300 via the telephone communication network 501.
The common key table 230 is an example of the first encryption key table of the present invention, and the common key 233 is an example of a plurality of encryption keys that can be used to encrypt the one-time password and transaction information in the present invention. Yes, the key number 232 is an example of encryption key designation information, and the secret key 240 is an example of an encryption key for encrypting the encryption key designation information.

FIG. 4 shows an example of the configuration of transaction information 600.
The transaction information 600 includes a transaction ID (Identifier) 601, a transfer source account number 602, a transfer destination name 603, a transfer destination account number 604, and a transfer amount 605.
The transaction ID 601 is identification information that uniquely identifies a transaction.
The transfer source account number 602 indicates an account number of a bank or the like of a user who pays a transaction fee at the time of transaction.
The transfer destination name 603 indicates the name or name of the owner (transaction partner) of an account such as a bank to which the transaction fee is transferred.
A transfer account number 604 indicates an account number of a bank or the like of a trading partner to which the transaction fee is transferred.
A transfer amount 605 indicates a transaction fee to be transferred to an account of a counterparty bank or the like.
A user inputs a transfer source account number, a transfer destination name, a transfer destination account number, and a transfer amount using the portable information terminal 300 for each transaction. The portable information terminal 300 transmits them to the transaction business server 100 via the network 500. When receiving the transfer source account number, the transfer destination name, the transfer destination account number, and the transfer amount, the transaction operation unit 101 of the transaction operation server 100 assigns a transaction ID 601 for each transaction and creates transaction information 600. Then, the transaction business unit 101 transmits the transaction information 600 to the transaction authentication strengthening server 200.
The transfer source account number 602 is an example of portable information terminal specifying information of the present invention. Moreover, the account number 602, the transfer destination name 603, the transfer destination account number 604, and the transfer amount 605 are examples of the transaction content of the invention.

FIG. 5 shows an example of the configuration of the common key table 420 stored in the read only memory 410 of the password display dedicated machine 400.
The common key table 420 has fields for a key number 421 and a common key 422.
The common key table 230 shown in FIG. 3 stores each common key used in transactions for each user for a plurality of users. For this reason, the common key 233 is specified by the transfer source account number 231 and the key number 232. On the other hand, the common key table 420 stores only the common key used in the transaction of the user who exclusively uses the password display dedicated machine 400. Therefore, only the common key 422 specified by the key number 421 is stored in the common key table 420. However, when a user who uses the password display dedicated machine 400 has a plurality of transfer source accounts, the common key table 420 also has a transfer source account number field, and the common key 422 is the transfer source account number. And the key number 421.
The key number 421 is encrypted using the secret key 240, and the encrypted key number 421 is decrypted using the public key 430.
The common key table 420 is an example of a second encryption key table of the present invention, the common key 422 is an example of a plurality of encryption keys in the present invention, and the key number 421 is an example of encryption key designation information of the present invention. The public key 430 is an example of a decryption key corresponding to the encryption key (that is, the secret key 240) stored by the encryption key specifying information encryption key storage means of the transaction authentication strengthening server 200 in the present invention.

FIG. 6 shows an example of an operation of a user (user) who performs a transaction.
The user logs in to transaction business server 100 using portable information terminal 300. Then, every time the user performs a transaction, the user operates the input unit 303 of the portable information terminal 300 to input the transfer source account number, the transfer destination name, the transfer destination account number, and the transfer amount (S701). The transfer source account number, the transfer destination name, the transfer destination account number, and the transfer amount are examples of transaction contents of the present invention.
The data communication unit 305 of the portable information terminal 300 transmits the transaction content to the transaction business server 100 via the network 500. The transaction business unit 101 of the transaction business server 100 transmits the transaction information 600 to the transaction authentication strengthening server 200 (S702). The authentication strengthening unit 201 of the transaction authentication strengthening server 200 converts the transaction information 600 and the one-time password into voice data, and sends it to the portable information terminal 300 via the telephone communication network 501 (S703). The user confirms that the outgoing telephone number displayed on the telephone communication unit 301 of the portable information terminal 300 is an incoming call from the correct partner, and depresses the call button (S704). When the telephone communication unit 301 of the portable information terminal 300 receives the voice data, the voice output unit 302 outputs the transaction information 600 and a sound indicating a one-time password to the password display dedicated machine 400 (S705). After that, as shown in FIG. 7, the display unit 403 of the password display dedicated machine 400 displays a part of the transaction contents (transfer destination name, transfer destination account number, and transfer amount) and a one-time password (S706). The user checks whether or not the transaction content matches the transaction intended by the user. If the transaction content matches, the one-time displayed on the display unit 403 by operating the input unit 303 of the portable information terminal 400 A password is input (S707). The data communication unit 305 transmits the one-time password to the transaction business server 100 via the network 500.

FIG. 8 shows an example of the processing flow of the transaction business unit 101 and the authentication strengthening unit 201.
The range of processing described with reference to FIG. 8 is after the transaction business unit 101 starts a transaction business (S801) when the user manually operates the transaction using the portable information terminal 300 in step S701. In step S704, the user inputs the one-time password manually using the portable information terminal 300, and the transaction business unit 101 executes the transaction (S809).

When the transaction business unit 101 starts the transaction business (S801), it next transmits the transaction information 600 to the authentication strengthening unit 201 to request authentication (S802), and waits for reception of the transmission result (S803).
When the authentication strengthening unit 201 receives the transaction information 600 transmitted from the transaction business unit 101 (S901), the authentication strengthening unit 201 generates a one-time password corresponding to the transaction information 600 (S902). Next, the authentication strengthening unit 201 encrypts the transaction information and the one-time password using the common key (S903). Since a plurality of common keys to be used for encryption are prepared, the authentication strengthening unit 201 determines a key number 232 using a numerical value (random number) generated at random, and from the common key table 230, the key number 232 and The common key 233 specified by the combination of the transfer source account number 231 is taken out. Next, the authentication strengthening unit 201 encrypts the used key number 232 using the secret key 240 (S904). The secret key 240 is for creating encrypted data that can be decrypted with the public key 430 stored in the read-only memory 410 of the password-only machine 400.

Then, the telephone transmission unit 202 converts data to be sent to the portable information terminal 300 into voice data (S905). At that time, for example, a method of converting image data such as FAX (facsimile) into audio data is used. Here, the three data, which are already encrypted, are the key number 232 of the common key, the transaction information 600, and the one-time password.
Next, the telephone transmission unit 202 makes a telephone call to the portable information terminal 300 (S906). At this time, the telephone transmission unit 202 refers to the telephone number table 220 and extracts the telephone number 222 corresponding to the transfer source account number 602 included in the transaction information 600. Then, the telephone transmission unit 202 transmits the transmission result to the transaction business unit 101 (S907).

The telephone transmission unit 202 determines whether or not communication is established (S908). If communication is not established (S908: NO), the processing of the authentication strengthening unit 201 is terminated. On the other hand, if communication is established (S908: YES), the telephone transmission unit 202 transmits voice data to the portable information terminal 300 (S909).
When the telephone communication unit 301 of the portable information terminal 300 receives the audio data, the audio output unit 302 converts the audio data into sound and outputs the sound to the password display dedicated device 400 (S702). The user looks at the one-time password displayed on the display unit 403 of the password display-only device 400 and inputs the one-time password by manual operation from the input unit 303 of the portable information terminal 300 (S704). The data communication unit 305 of the portable information terminal 300 transmits the input one-time password to the transaction business server 100.
When receiving the one-time password (S805), the transaction business unit 101 of the transaction business server 100 transmits the one-time password to the authentication strengthening unit 201 of the transaction authentication server 200 and requests authentication (S806).
The authentication strengthening unit 201 of the transaction authentication strengthening server 200 collates the received password with the password generated in step S902 (S910), and transmits the collation result to the transaction business unit 101 (S911). When receiving the authentication result (S807), the transaction business unit 101 cancels the transaction if the authentication is NG (S808: NO), and executes the transaction if the authentication is OK (S808: YES) (S809).

FIG. 9 shows an example of the flow of processing in the password display dedicated machine 400.
When the portable information terminal 300 outputs a sound to the password display dedicated device 400 in step S702, the voice input unit 401 inputs the sound (S1001).
Then, the information extraction unit 402 extracts the encrypted common key number, transaction information, and one-time password from the information included in the sound (S1002). Next, the information extraction unit 402 takes out the public key 430 from the read-only memory 410 (S1003). Next, the information extraction unit 402 uses the extracted public key 430 to decrypt the key number of the common key (S1004). Next, the information extraction unit 402 extracts the common key 422 corresponding to the key number of the common key from the common key table 420 of the read-only memory 410 (S1005). Next, the information extraction unit 402 decrypts the transaction information 600 and the one-time password using the common key 422 (S1006).
The display unit 403 of the password display dedicated machine 400 displays a part of the transaction contents (transfer destination name, transfer destination account number and transfer amount) and one-time password (S706).

  In the above-described embodiment, the telephone transmission unit 202 of the transaction authentication strengthening server 200 transmits a call to the portable information terminal 300, and voice data including the one-time password and the transaction information 600 is transmitted via the telephone communication network 501. Although it is assumed that the converted sound is transmitted, the transaction authentication strengthening server 200 transmits the sound data to the portable information terminal 300 via the network 500, and the sound data received by the application software operating on the portable information terminal 300 is used as the sound. It may be converted.

  In the above-described embodiment, the number for identifying the common key is encrypted using the private key 240 in the authentication strengthening unit 201 of the transaction authentication strengthening server 200 and encrypted in the information extracting unit 402 of the password display dedicated device 400. Although the encrypted number is decrypted by using the public key 430, the number for identifying the common key may be left in plain text without being encrypted, or used at the previous transaction in the portable information terminal 300 A number for identifying the common key used in the current transaction may be encrypted and decrypted using the common key.

  As described above, according to the present invention, there is provided an authentication system that can withstand a man-in-the-middle attack, malware infection of a portable information terminal, and unauthorized transactions due to hijacking on the condition that only the portable information terminal communicates with the server. Can be provided.

  Although the embodiments of the present invention have been described above, various modifications and combinations necessary for design reasons and other factors are described in the inventions described in the claims and the specific embodiments described in the embodiments of the invention. It should be understood that it falls within the scope of the invention corresponding to the examples.

DESCRIPTION OF SYMBOLS 1 ... Authentication system, 100 ... Transaction business server, 101 ... Transaction business part, 200 ... Transaction authentication reinforcement | strengthening server, 201 ... Authentication reinforcement | strengthening part, 202 ... Telephone transmission part, 210 ... Database, 220 ... Telephone number table, 230 ... Common key Table: 240 ... Secret key 300 ... Portable information terminal 301 ... Telephone communication unit 302 ... Audio output unit 303 ... Input unit 304 ... Display unit 305 ... Data communication unit 400 ... Dedicated machine for password display 401 ... Voice input unit, 402 ... Information extraction unit, 403 ... Display unit, 410 ... Read only memory, 420 ... Common key table, 430 ... Public key, 500 ... Network, 501 ... Telephone communication network, 600 ... Transaction information

Claims (5)

An authentication system having a transaction business server, a transaction authentication strengthening server, a portable information terminal, and a password display dedicated machine,
The transaction server is
A transaction authentication requesting means for generating a transaction information including the transaction content and transmitting a transaction authentication request including the transaction information to the transaction authentication strengthening server upon receiving a transaction operation request including the transaction content from the portable information terminal; ,
When the one-time password is received from the portable information terminal, the one-time password is transmitted to the transaction authentication strengthening server, and when the authentication success is notified from the transaction authentication strengthening server, the transaction business is performed according to the transaction content. Means,
With
The transaction authentication strengthening server is
When receiving a transaction authentication request from the transaction business server, a one-time password generating means for generating a one-time password;
Voice data transmitting means for converting the one-time password and transaction information generated by the one-time password generating means into voice data and transmitting the voice data to the portable information terminal;
When the one-time password is received from the transaction business server, the received one-time password is compared with the one-time password generated by the one-time password generation means to determine whether or not the authentication is successful. An authentication means for notifying the transaction server of successful authentication when successful,
With
The portable information terminal is
Transaction content accepting means for accepting the transaction content entered by the user;
Transaction information transmitting means for transmitting a transaction business request including the transaction content received by the transaction content reception means to the transaction business server;
Voice receiving means for receiving the voice data from the transaction authentication strengthening server;
Voice output means for converting voice data received by the voice receiving means into sound and outputting the sound;
One-time password accepting means for accepting a one-time password input by the user;
One-time password transmission means for transmitting the one-time password accepted by the one-time password acceptance means to the transaction business server;
With
The dedicated password display machine
Voice input means for inputting sound output by the portable information terminal;
Information extraction means for extracting one-time password and transaction information from information included in the sound input by the voice input means;
Display means for displaying the one-time password extracted by the information extraction means and part or all of the extracted transaction information;
Comprising
An authentication system characterized by that. The transaction content includes mobile information terminal specifying information for specifying a mobile information terminal,
The transaction authentication strengthening server comprises a phone number table including the mobile information terminal specifying information and a phone number of the mobile information terminal specified by the mobile information terminal specifying information,
The voice data transmitting means of the transaction authentication strengthening server acquires a telephone number corresponding to the portable information terminal specifying information included in the transaction contents from the telephone number table, and makes a call to the acquired telephone number, and performs telephone communication. Sending the voice data over the network,
Voice receiving means of the portable information terminal receives voice data transmitted via the telephone communication network;
The authentication system according to claim 1, wherein: The transaction authentication strengthening server includes an encryption unit that encrypts the one-time password generated by the one-time password generation unit and the transaction information included in the transaction authentication request.
The voice data transmission means of the transaction authentication strengthening server converts the one-time password and transaction information encrypted by the encryption means into voice data, and transmits the voice data to the portable information terminal,
The information extraction unit of the password display dedicated machine extracts the encrypted one-time password and transaction information from information included in the sound input by the voice input unit, and the encrypted one-time password and transaction Decrypt information,
The authentication system according to claim 1 or 2, characterized in that. The transaction authentication strengthening server designates a plurality of encryption keys that can be used to encrypt the one-time password and the transaction information, and an encryption key that is used to encrypt the plurality of encryption keys. A first encryption key table having encryption key designation information to be
The encryption means of the transaction authentication strengthening server acquires an encryption key specified by the encryption key specification information acquired by a predetermined method from the first encryption key table, and uses the acquired encryption key to Encrypt one-time password and transaction information,
The voice data transmission means of the transaction authentication strengthening server specifies the encryption key used to encrypt the one-time password and transaction information in addition to the one-time password and transaction information encrypted by the encryption means. The encryption key designation information to be converted into voice data, the voice data is transmitted to the portable information terminal,
The password display dedicated machine includes a second encryption key table having the plurality of encryption keys and the encryption key designation information;
The information extraction unit of the password display dedicated machine extracts the encrypted one-time password and transaction information and the encryption key designation information from information included in the sound input by the voice input unit, and the encryption key Obtaining an encryption key designated by the designated information from the second encryption key table, and decrypting the encrypted one-time password and transaction information using the obtained encryption key;
The authentication system according to claim 3. The transaction authentication strengthening server comprises encryption key storage means for encryption key specification information for storing an encryption key for encrypting the encryption key specification information,
The encryption means of the transaction authentication strengthening server encrypts the encryption key designation information using the encryption key stored in the encryption key designation information encryption key storage means;
The voice data transmission means of the transaction authentication strengthening server converts the encryption key designation information encrypted in addition to the one-time password and the transaction information encrypted by the encryption means into voice data, Send to the mobile information terminal,
The password display-dedicated machine comprises encryption key designation information decryption key storage means for storing a decryption key corresponding to the encryption key stored by the encryption key designation information encryption key storage means of the transaction authentication strengthening server;
The information extraction means of the password display dedicated machine extracts the encrypted one-time password and transaction information and the encrypted encryption key designation information from information included in the sound input by the voice input means. , Decrypting the encrypted encryption key designation information using the decryption key stored in the encryption key designation information decryption key storage means, and obtaining an encryption key designated by the decrypted encryption key designation information Obtaining from the second encryption key table;
The authentication system according to claim 4.

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