WO2024122069A1

WO2024122069A1 - Self authentication system and self authentication method

Info

Publication number: WO2024122069A1
Application number: PCT/JP2022/045567
Authority: WO
Inventors: 貴利中村; 直太高橋
Original assignee: 株式会社エヌティーアイ; 株式会社ナンバーワンソリューションズ
Priority date: 2022-12-09
Filing date: 2022-12-09
Publication date: 2024-06-13

Abstract

A server S_E generates a token T_A preserved in a user terminal U_E, and transmits T_A to U_E. S_E associates a user with T_A, and associates an issued OTP with T_A. S_E issues a notification in which a link L_I having a series of characters based on T_A is described. In U_E, when a token based on L_I designated on the notification is the same as the preserved T_A, S_E receives an HTTP request from U_E according to the L_I and transmits, to U_E, an HTTP response to the OPT. A requirement for successful self authentication is that an OPT input by the user is the same as the OPT associated with T_A associated with the user.

Description

Personal authentication system and method

The present invention generally relates to identity authentication.

　There is known a personal authentication technology that uses a one-time password (hereinafter, OTP). An "OTP" is a character string (generally a random number) that can be used only once. The "character string" is composed of multiple (or one) characters, and each character may be any of the following: alphabet, numbers, and other symbols. Typically, an OTP is a character string that can be used an upper limit of one number of times, but the "OTP" used in this specification may be an extended OTP that can be used an upper limit of two or more times, or an extended OTP that has an upper limit on the period of use instead of or in addition to the number of times it can be used.

One example of a personal authentication technology that uses OTP is the technology disclosed in Patent Document 1.

JP 2011-215940 A

WEB functions are used to provide services via the Internet. WEB functions generally involve sending a request specifying a URL (Uniform Resource Locator) from the web browser on a user's terminal to a server system, and the server system then displays the HTML (Hypertext Markup Language) file corresponding to that URL on the web browser on the user's terminal.

　If the OTP required for identity authentication could also be provided using WEB functions, user convenience would be improved. However, there is no method of securely providing an OTP to a user using WEB functions. This is because it is not possible to correctly verify both the user and the communication path.

Therefore, two-step authentication is generally adopted as a personal authentication method that uses the OTP. In two-step authentication, the OTP is transmitted to the user via email, SMS (Short Message Service), a dongle (hardware token), voice call, or an app (for example, an app for issuing OTPs that is separate from a browser or service app).

However, two-step authentication cannot prevent phishing scams. In other words, if a malicious third party obtains the authentication information (e.g., ID and password) entered by the user via a fake web screen and also obtains the OTP, the malicious third party can masquerade as the user.

A server system that communicates with a user terminal having a web browser generates a token and transmits the generated token stored by the user terminal via HTTP. The server system associates the user with the generated token and associates an issued OTP with the generated token associated with the user. The server system transmits a link notification addressed to the user, which describes an OTP link, which is a link having a character string based on the generated token. If the token on which the character string of the specified OTP link on the issued link notification is based matches the stored token, the server system receives an HTTP request according to the OTP link from the user terminal and transmits an HTTP response of the OTP to the user terminal. A requirement for successful user authentication is that the OTP entered by the user matches the OTP associated with the token to which the user is associated.

According to the present invention, OTP can be provided securely using WEB functions.

1 is a diagram showing a system configuration according to an embodiment of the present invention; 1 is a part of an authentication process performed in one embodiment of the present invention. 4 is the remainder of the authentication process performed in one embodiment of the present invention.

In the following description, an "interface unit" may refer to one or more interface devices. The one or more interface devices may be at least one of the following:
One or more I/O (Input/Output) interface devices. The I/O (Input/Output) interface devices are interface devices to at least one of the I/O devices and a remote display computer. The I/O interface device to the display computer may be a communications interface device. The at least one I/O device may be a user interface device, e.g., either an input device such as a keyboard and a pointing device, or an output device such as a display device.
One or more communication interface devices. The one or more communication interface devices may be one or more homogeneous communication interface devices (e.g., one or more NICs (Network Interface Cards)) or two or more heterogeneous communication interface devices (e.g., a NIC and an HBA (Host Bus Adapter)).

Furthermore, in the following description, "memory" refers to one or more memory devices, typically a primary storage device. At least one of the memory devices in the memory may be a volatile memory device or a non-volatile memory device.

Furthermore, in the following description, a "persistent storage device" refers to one or more persistent storage devices. A persistent storage device is typically a non-volatile storage device (e.g., an auxiliary storage device), specifically, for example, a hard disk drive (HDD) or a solid state drive (SSD).

In the following description, "storage device" may refer to at least one memory, including memory and persistent storage device.

Furthermore, in the following description, a "processor" refers to one or more processor devices. The at least one processor device is typically a microprocessor device such as a CPU (Central Processing Unit), but may also be other types of processor devices such as a GPU (Graphics Processing Unit). The at least one processor device may be a single-core or multi-core. The at least one processor device may be a processor core. The at least one processor device may also be a processor device in the broader sense, such as a hardware circuit that performs part or all of the processing (e.g., an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit)).

In the following description, functions are sometimes described using the expression "yyy unit", but the functions may be realized by one or more computer programs being executed by a processor, or by one or more hardware circuits (e.g., FPGAs or ASICs), or by a combination of these. When a function is realized by a program being executed by a processor, the function may be at least a part of the processor, since the specified processing is performed using a storage device and/or an interface device, etc., as appropriate. Processing described with a function as the subject may be processing performed by a processor or a device having the processor. A program may be installed from a program source. The program source may be, for example, a program distribution computer or a storage medium (e.g., a non-transitory storage medium) that is readable by a computer. The description of each function is an example, and multiple functions may be combined into one function, or one function may be divided into multiple functions.

Below, one embodiment of the present invention will be described in detail with reference to the drawings. In the following embodiment, login authentication is adopted as an example of personal authentication, login information such as an ID and password is adopted as authentication information for personal authentication, and a login page into which an ID and password are input is adopted as a web page for inputting authentication information for personal authentication.

FIG. 1 shows the system configuration for one embodiment of the present invention.

Communication takes place between the user terminal 150 and the server system 100 via a communication network such as the Internet.

The user terminal 150 is an information processing terminal such as a personal computer or a smartphone. The user terminal 150 has an IF device (interface device) 160, a storage device 180, and a processor 190 connected to them. The user terminal 150 also has a UI (User Interface) device 170 connected to the IF device 160.

The IF device 160 communicates with the IF device 110 (described below) of the server system 100, and with the UI device 170.

The UI device 170 is at least one of an input device such as a keyboard or a mouse, and a display device such as a liquid crystal display. The UI device 170 may be a device in which the input device and the display device are integrated, such as a touch panel.

The storage device 180 stores a key U. The key U is one or more user keys. The user keys are used to encrypt and decrypt information. Hereinafter, the nth user key will be represented as "K _Un " (n is a natural number). A different user key may be used for each object of multiple cryptographic communication (e.g., an argument as an example of information), or a common user key may be used regardless of the object of multiple cryptographic communication.

The processor 190 functions as a web browser 191, a token management unit 192, and an encryption unit 193. These functions 191 to 193 are realized by the processor 190 executing at least a part of one or more computer programs including or excluding the OS (Operating System) of the user terminal 150. For example, at least one of the token management unit 192 and the encryption unit 193 may be a function prepared in advance in the user terminal 150 (e.g., a plug-in for the web browser 191), or may be a function embedded in a web page from the server system 100 as a JAVA script ("JAVA" is a registered trademark) (a function obtained from a web page). These functions 191 to 193 will be explained in the explanation of the authentication process shown in Figures 2 and 3.

The server system 100 may be a physical system consisting of one or more physical computers having computing resources such as an IF device 110, a storage device 120, and a processor 130 connected to them, or it may be a logical system based on such a physical system (e.g., a system as a cloud computing service).

IF device 110 communicates with IF device 160 of user terminal 150.

The storage device 120 stores the key S and the management DB (database) 121.

The key S is one or more server keys corresponding to one or more user keys. The server key is used for encrypting and decrypting information. The server key used may be different for each multiple encryption communication target (e.g., an argument as an example of information), or the server key may be common regardless of the multiple encryption communication target. In this embodiment, the user key and the server key are assumed to correspond to each other on a one-to-one basis. Hereinafter, the n-th server key corresponding to the n-th user key K _Un is represented as "K _Sn ". It may be predetermined which user key and which server key are used in which multiple encryption communication, or any user key and server key may be used regardless of which multiple encryption communication is used.

Management DB121 is an example of management information, and includes information for each user. For example, for each user, the user information includes authentication information such as the user's ID and password. In addition, for each user, a token and OTP are added to the user information as appropriate. Note that the user authentication information may include other types of information, such as the user's biometric information, instead of or in addition to at least one of the ID and password.

The processor 130 functions as a token management unit 131, a WEB-IF unit 132, an encryption unit 133, an OTP management unit 134, and an authentication unit 135. These functions 131 to 135 are realized by the processor 130 executing at least a part of one or more computer programs including or excluding the OS of the server system 100. Furthermore, an explanation of these functions 131 to 135 will be given in the explanation of the authentication process shown in Figures 2 and 3.

FIGS. 2 and 3 show the authentication process performed in one embodiment of the present invention.

In S201, the web browser 191 of the user terminal 150 sends an HTTP request to the server system 100. The "HTTP request" referred to here is a request in which the URL of a login page is specified, but instead of such a request, an HTTP request in which the URL of a web page other than the login page is specified may be used. If the server system 100 determines in response to this HTTP request that the user's login authentication has not been completed, an HTTP response of the login page may be provided to the user terminal 150.

S202: The server system 100 receives the HTTP request sent in S201 (or the HTTP request sent by redirection). In response to the HTTP request, the token management unit 131 of the server system 100 generates a token (hereinafter, token A) and temporarily stores it, for example, in the storage device 120. Token A is, for example, a character string as a random number. The WEB-IF unit 132 of the server system 100 provides the user terminal 150 with an HTTP response of a login page to which token A is associated (for example, embedded).

S203: The web browser 191 of the user terminal 150 displays the login page from the server system 100, and the token management unit 192 of the user terminal 150 saves the token A associated with the login page. The destination for saving the token A may be the storage device 180 (i.e., local storage), but instead of or in addition to that, it may also be session storage.

S204: The web browser 191 of the user terminal 150 accepts input of an ID and PW (password) for the login page.

S205: For example, if a login button on a login page is pressed in S204, the web browser 191 of the user terminal 150 passes an argument (hereinafter, argument P), which is information including the input ID and password, to the encryption unit 193, and the encryption unit 193 encrypts the argument P using the first user key K _U1 and the above-mentioned stored token A (encryption password). The argument P may include information other than the ID and password (for example, a timestamp). The argument encrypted using the first user key K _U1 is represented as "argument E _U1 ".

S206: The WEB browser 191 of the user terminal 150 transmits an HTTP request (for example, a request for personal authentication) associated with the argument _EU1 .

S207: The server system 100 (for example, the WEB-IF unit 132) receives the HTTP request associated with the argument E _U1 , and the encryption unit 133 of the server system 100 encrypts the argument E _U1 using the temporarily stored token A (encryption password) and the first server key K _S1 . The argument encrypted using the first user key K _U1 and the first server key K _S1 , that is, the multiple-encrypted argument, is represented as "argument E _U1S1 ". The server system 100 (for example, the WEB-IF unit 132) transmits the argument E _U1S1 to the user terminal 150.

S208: The user terminal 150 (e.g., the WEB browser 191) receives the argument E _U1S1 , and the encryption unit 193 of the user terminal 150 decrypts the argument E _U1S1 using the stored token A (decryption password) and the first user key K _U1 . This results in the argument E _S1 in which the argument P is encrypted with the first server key K _S1 . The user terminal 150 (e.g., the WEB browser 191) transmits the argument E _S1 to the server system 100.

S209: The server system 100 (for example, the WEB-IF unit 132) receives the argument E _S1 , and the encryption unit 133 of the server system 100 decrypts the argument E _S1 using the temporarily stored token A (decryption password) and the first server key K _S1 . This obtains the argument P, and therefore the ID and password can be obtained from the argument P.

The multiple encryption communication in S206 to S209 (communication between the WEB browser 191 of the user terminal 150 and the WEB-IF unit 132 of the server system 100) is performed using HTTP. That is, the transmission and reception of the argument E _U1 , the argument E _U1S1 , and the argument E _S1 is performed using HTTP. In addition, in this embodiment, the Vernam cipher is used for encryption using the key and the encryption password, and for decryption using the key and the decryption password. Methods other than the Vernam cipher may be used for encryption and decryption.

S210: The authentication unit 135 of the server system 100 determines whether or not there is information in the management DB 121 that includes an ID and password that match the ID and password obtained from the argument P. If the result of this determination is false (S210: NO), the authentication unit 135 performs error processing (for example, sending a message to the user terminal 150 instructing the user to re-enter the ID or password). If the result of this determination is true (S210: YES), the process proceeds to S211 in FIG. 3.

S211: The token management unit 192 of the server system 100 includes the temporarily stored token A in the information (information in the management DB 121) of the user corresponding to the ID and password of S210: YES. In other words, the token management unit 192 associates the user with token A. The WEB-IF unit 132 of the server system 100 provides the user terminal 150 with an OTP input page, which is a WEB page for OTP input with which token A is associated (e.g., embedded). The OTP input page may be provided as an HTTP response to the HTTP request sent in S206.

S212: The web browser 191 of the user terminal 150 displays the OTP input page from the server system 100. At this stage, the token management unit 192 of the user terminal 150 may determine whether or not a token matching the stored token A is associated with the OTP input page. If the result of this determination is false, the user terminal 150 (e.g., the web browser 191) may perform error processing (e.g., display a warning message indicating that the page is invalid).

S213: In parallel with S211, the OTP management unit 134 of the server system 100 transmits a URL notification to the user whose ID and password have been authenticated in S210. The "URL notification" is a notification (e.g., an email or an SMS message) in which an OTP-URL, which is a URL (an example of a link) having a character string based on the token A (a character string including the token A in this embodiment), is described. In this embodiment, the OTP-URL includes a character string as an argument (i.e., the argument E _U1 ) that can be decrypted using the first user key K _U1 and the token A. The argument E _U1 is an argument associated with the request transmitted to the server system 100 in S206.

S214: The user terminal 150 (for example, a mail application or SMS application, not shown) displays the URL notification from the server system 100 and accepts a user operation to specify the URL described in the notification.

S215: The encryption unit 193 of the user terminal 150 decrypts the character string in the specified URL (the character string as the argument _EU1 ) using the first user key K _U1 and the token A stored above.

S216: The token management unit 192 of the user terminal 150 determines whether the token obtained by decryption in S215 matches the stored token A. If the result of this determination is false, the user terminal 150 (e.g., the web browser 191) may perform error processing (e.g., displaying a message instructing the user to start over by entering the ID and password). If the result of this determination is true (S216: YES), the process proceeds to S217.

S217: The web browser 191 of the user terminal 150 sends an HTTP request specifying the OTP-URL (a request for the OTP display page, which is a web page that displays the OTP).

S218: The server system 100 (e.g., the WEB-IF unit 132) receives a request specifying an OTP-URL, and the OTP management unit 134 of the server system 100 issues an OTP and associates the OTP with information (information in the management DB 121) corresponding to the user whose ID and password were authenticated in S210. In other words, the OTP management unit 134 associates the issued OTP with the token associated with the user. Note that the OTP may be issued at any timing after S210: YES, instead of when an HTTP request specifying an OTP-URL is received. The OTP may also be issued by a system external to the server system 100.

S219: The following multiple encryption communication is performed. The target of this multiple encryption communication is the OTP. The OTP may be transmitted to the user terminal 150 without being multiple encrypted.
(X1) The encryption unit 133 of the server system 100 encrypts the issued OTP using the token A (encryption password) and the second server key K _S2 . This encrypted OTP is denoted as "OTP-E _S2 ". Also, for example, in the case where there is only one server key in the key S, the first server key K _S1 and the second server key K _S2 may be the same key. The server system 100 (for example, the WEB-IF unit 132) transmits the OTP-E _S2 to the user terminal 150.
(X2) The user terminal 150 (for example, the WEB browser 191) receives the OTP-E _S2 , and the encryption unit 193 of the user terminal 150 encrypts the OTP-E _S2 using the stored token A (encryption password) and the second user key K _U2 corresponding to the second server key K _S2 . The OTP encrypted using the second server key K _S2 and the second user key K _U2 , that is, the multiple-encrypted OTP, is represented as "OTP-E _S2U2 ". The user terminal 150 (for example, the WEB browser 191) transmits the OTP-E _S2U2 to the server system 100.
(X3) The server system 100 (for example, the WEB-IF unit 132) receives the OTP-E _S2U2 , and the encryption unit 133 of the server system 100 decrypts the OTP-E _S2U2 using the token A (decryption password) and the second server key K _S2 . This results in the OTP-E _U2 being encrypted with the second user key K _U2 . The server system 100 (for example, the WEB-IF unit 132) transmits the OTP-E _U2 to the user terminal 150.
(X4) The user terminal 150 (for example, the WEB browser 191) receives the OTP- _EU2 , and the encryption unit 193 of the user terminal 150 decrypts the OTP- _EU2 using the stored token A (decryption password) and the second user key K _U2 . As a result, the OTP is obtained.

The multiple encryption communication related to (X1) to (X4) (communication between the WEB browser 191 of the user terminal 150 and the WEB-IF unit 132 of the server system 100) is performed by HTTP. That is, the transmission and reception of OTP-E _S2 , OTP-E _S2U2 and OTP-E _U2 is performed by HTTP.

S220: The web browser 191 of the user terminal 150 displays the OTP from the server system 100 (e.g., the OTP decrypted with (X4)).

S221: The web browser 191 of the user terminal 150 accepts the OTP input on the OTP input page.

S222: When, for example, a login button on an OTP input page is pressed in S221, the WEB browser 191 of the user terminal 150 transmits an HTTP request. In this request, (token/ID) _U3 is specified. "(token/ID) _U3 " is the token A and ID (user ID entered for login) encrypted using the OTP (encryption password) and the third user key K _U3 . In this embodiment, the token A and ID are the targets of multiple encryption communication. Specifically, the following is performed. Note that the third user key K _U3 may be the same user key as the first user key K _U1 or the second user key K _U2 , or may be a user key different from these user keys.
(Y1) The server system 100 (for example, the WEB-IF unit 132) receives the (token/ID) _U3 , and the encryption unit 133 of the server system 100 encrypts the (token/ID) _U3 using the issued OTP (decryption password) and the third server key K _S3 (a server key corresponding to the third user key K _U3 ). The token/ID encrypted using the third user key K _U3 and the third server key K _S3 , that is, the multiple-encrypted token/ID, is represented as "(token/ID) _U3S3 ". The server system 100 (for example, the WEB-IF unit 132) transmits the (token/ID) _U3S3 to the user terminal 150.
(Y2) The user terminal 150 (e.g., the WEB browser 191) receives the (token/ID) _U3S3 , and the encryption unit 193 of the user terminal 150 decrypts the (token/ID) _U3S3 using the stored OTP (decryption password) and the third user key K _U3 . This results in the (token/ID) _S3 in a state in which the token/ID is encrypted with the third server key K _S3 . The user terminal 150 (e.g., the WEB browser 191) transmits the (token/ID) _S3 to the server system 100.
(Y3) The server system 100 (for example, the WEB-IF unit 132) receives the (token/ID) _S3 , and the encryption unit 133 of the server system 100 decrypts the (token/ID) _S3 using the issued OTP (decryption password) and the third server key K _S3 . As a result, the token/ID is acquired.

The multiple encryption communication related to (Y1) to (Y3) (communication between the WEB browser 191 of the user terminal 150 and the WEB-IF unit 132 of the server system 100) is performed by HTTP. That is, the transmission and reception of (token/ID) _U3 , (token/ID) _U3S3 , and (token/ID) _S3 is performed by HTTP.

S223: The authentication unit 135 of the server system 100 refers to the management DB 121 and determines whether the token/ID matches token A and the ID of the user (the user whose ID and password were authenticated in S210). If the result of this determination is false (S223: NO), the authentication unit 135 performs error processing (for example, sending a message to the user terminal 150 indicating that the user should re-enter the ID or password). If the result of this determination is true (S223: YES), the process proceeds to S224.

S224: The authentication unit 135 of the server system 100 allows the user to log in (personal authentication successful).

When considering this embodiment, it is expected that the following problems can be avoided:

Firstly, there may be a case where the login page is a fake page, and a third party attempts to impersonate the user by using the ID and password entered on the fake page. However, when the OTP-URL in the URL notification is specified by the third party, a token mismatch is detected in S216. This is because token A (the correct token) does not exist on the third party's user terminal. Therefore, S216: NO (error) occurs, and processing does not proceed. As a result, the problem in this case can be avoided.

Secondly, the URL notification may be a false notification. However, when the OTP-URL in the URL notification is specified by the user, a token mismatch is detected in S216. This is because the character string in the OTP-URL is not based on token A. Therefore, S216: NO (error) is returned, and processing does not proceed.

Thirdly, the URL notification may be stolen by a third party. However, this problem can be avoided by using either of the following methods (3-1) or (3-2).
(3-1) When the OTP-URL in the URL notification is specified by a third party, a token mismatch is detected in S216. This is because the same token A as the token A on which the character string of the OTP-URL is based is not stored in the user terminal of the third party. Therefore, S216: NO (error) is returned, and the process does not proceed.
(3-2) The OTP to be transmitted in S219 is the target of multiple encryption communication using token A as the encryption password. Token A is not stored in the third party's user terminal. For this reason, decryption of the multiple encrypted OTP fails.

Fourth, there may be a case where the OTP input page is a fake page and a third party tries to impersonate a user by using the OTP input on the fake page. However, the problem in this case can be avoided by either of the following methods (4-1) or (4-2).
(4-1) The input OTP is not associated with a third party in the server system 100. Therefore, S223: NO (error), that is, the identity authentication fails.
(4-2) The input OTP is the subject of multiple encryption communication using token A as the decryption password in server system 100. However, token A is not stored in the third party's user terminal. Therefore, decryption fails in server system 100.

The above explanation can be summarized, for example, as follows. The summary below may include supplements and variations of the above explanation.

The personal authentication system includes a token management unit 131, a WEB-IF unit 132, and an OTP management unit 134 provided in the server system 100. The personal authentication system also includes a token management unit 192 provided in a user terminal 150 having a WEB browser 191. The token management unit 131 of the server system 100 generates token A. The WEB-IF unit 132 of the server system 100 transmits the generated token A to the user terminal 150 by HTTP. The token management unit 192 of the user terminal 150 stores the token A from the server system 100. The OTP management unit 134 of the server system 100 associates the issued OTP required for user personal authentication with the token A generated in the server system 100 and associated with the user. The OTP management unit 134 of the server system 100 transmits a link notification (for example, the above-mentioned URL notification) addressed to the user in which an OTP link, which is a link having a character string based on the token A, is described. When the OTP link described in the issued link notification is specified, the token management unit 192 of the user terminal 150 judges whether the token on which the character string of the specified OTP link is based matches the stored token A. If the result of the judgment is positive, the user terminal 150 (WEB browser 191) sends an HTTP request according to the OTP link. When the server system 100 receives the HTTP request according to the OTP link, the WEB-IF unit 132 of the server system 100 sends an HTTP response of the OTP to the user terminal 150, and the WEB browser 191 of the user terminal 150 displays the OTP. A requirement for successful user authentication is that the OTP entered by the user matches the OTP associated with the token to which the user is associated.

This allows the OTP to be provided securely via the WEB function, and even if the OTP is notified via the WEB function, both the user and the communication path can be correctly confirmed. Specifically, the token generated in the server system 100 is sent to the user terminal 150 via HTTP and stored in the user terminal 150, and in subsequent communications, if a token mismatch is detected, processing will not proceed.

In the above, a "character string based on token A" can be either a character string that includes token A, or a character string that is information encrypted using token A as the encryption password (this character string may or may not include token A).

Furthermore, "whether or not the token on which the character string of the specified OTP link is based matches the stored token A" may be, for example, any of the following.
- Whether or not the token obtained from the character string contained in the specified OTP link matches the stored token A.
- Whether or not the character string contained in the specified OTP link can be successfully decrypted (for example, decrypted according to the Vernam cipher) using the stored token A as the decryption password.

The generation and transmission of token A may be performed when the user is unspecified, or when the user is specified (for example, when the user is specified as the user of a user terminal connected to the company network). An "specified user" may be a user who has not yet had their authentication information such as ID and password authenticated but who has been specified as belonging to a specific range, or a user whose authentication information such as ID and password has been authenticated.

The WEB-IF unit 132 of the server system 100 provides a first WEB page (e.g., a login page) that is a WEB page that accepts input of information for personal authentication, and a second WEB page (e.g., an OTP input page) that is a WEB page that accepts input of an OTP. At least one of the first and second WEB pages has the generated token A. In this way, since the token A is transmitted together with the WEB page (e.g., embedded in the WEB page), communication only for transmitting the token A is not required. Note that in the embodiment, the first transmission of the token A is the transmission of a login page in which the token A is embedded, but instead, the transmission of an OTP input page in which the token A is embedded after S210: YES may be performed.

The server system 100 has an encryption unit 133 and a server key. The user terminal 150 has an encryption unit 193 and a user key. At least one of the information sent from the server system 100 to the user terminal 150 (typically, information associated with an HTTP response from the server system 100 to the user terminal 150) and the information sent from the user terminal 150 to the server system 100 (typically, information associated with an HTTP request from the user terminal 150 to the server system 100) is subject to multiple encryption. This makes it possible to prevent man-in-the-middle attacks. For example, as follows:

The encryption unit 133 of the server system 100 encrypts the target information, which is information to be sent to the user terminal 150 via HTTP, using the server key and the server-side encryption password, which is the generated token A. The WEB-IF unit 132 of the server system 100 sends the first encrypted information, which is the encrypted target information, to the user terminal 150 via HTTP. The encryption unit 193 of the user terminal 150 encrypts the first encrypted information from the server system 100 using the user key and the user-side encryption password, which is the stored token A. The WEB browser 191 of the user terminal 150 sends the second encrypted information, which is the encrypted first encrypted information, to the server system 100 via HTTP. The encryption unit 133 of the server system 100 decrypts the second encrypted information from the user terminal 150 using the server key and the same password as the server-side encryption password. The WEB-IF unit 132 of the server system 100 transmits the first encrypted information, which is the decrypted second encrypted information, to the user terminal 150 via HTTP. The encryption unit 193 of the user terminal 150 decrypts the first encrypted information from the server system 100 using the user key and the same password as the user-side encryption password to obtain the target information. In this way, it is possible to prevent man-in-the-middle attacks on the information transmitted from the server system 100 to the user terminal 150. Note that the "target information" referred to in this paragraph is, for example, an OTP. This allows for secret communication of the OTP.

The encryption unit 193 of the user terminal 150 encrypts the target information, which is information to be transmitted to the server system 100 via HTTP, using a user key and a user-side encryption password (at least one of the stored token A and the OTP from the server system 100). The WEB browser 191 of the user terminal 150 transmits the first encrypted information, which is the encrypted target information, to the server system 100 via HTTP. The encryption unit 133 of the server system 100 encrypts the first encrypted information from the user terminal 150 using a server key and a server-side encryption password (at least one of the generated token A and the issued OTP). The WEB-IF unit 132 of the server system 100 transmits the second encrypted information, which is the encrypted first encrypted information, to the user terminal 150 via HTTP. The encryption unit 193 of the user terminal 150 decrypts the second encrypted information from the server system 100 using the user key and the same password as the user-side encryption password. The web browser 191 of the user terminal 150 transmits the first encrypted information, which is the decrypted second encrypted information, to the server system 100 via HTTP. The encryption unit 133 of the server system 100 decrypts the first encrypted information from the user terminal 150 using the server key and the same password as the server-side encryption password to obtain the target information. In this way, it is possible to prevent man-in-the-middle attacks on the information transmitted from the user terminal 150 to the server system 100. Note that the "target information" referred to in this paragraph is, for example, information input by the user to a web page displayed by the web browser 191 of the user terminal 150. This realizes secret communication of the information input by the user (for example, authentication information or OTP).

In communication between the WEB browser 191 of the user terminal 150 and the WEB-IF unit 132 of the server system 100, the communication protocol may transition from a first HTTP (e.g., HTTP or HTTPS) to a second HTTP (which may be referred to as "HTTPM" for convenience). For example, this protocol transition may be performed by the WEB-IF unit 132. Communication according to HTTP is multiple encryption communication. The subject of the multiple encryption communication is at least a portion of the information (e.g., arguments of an HTTP request) sent from the WEB browser 191 of the user terminal 150 to the WEB-IF unit 132 of the server system 100 and the information (e.g., arguments of an HTTP response) sent from the WEB-IF unit 132 of the server system 100 to the WEB browser 191 of the user terminal 150. Multiple encryption includes encryption by the encryption unit 133 of the server system 100 using a server key and a server-side encryption password, and encryption by the encryption unit 193 of the user terminal 150 using a user key and a user-side encryption password. Both the server-side encryption password and the user-side encryption password may be at least one of token A and information transmitted and received between the server system 100 and the user terminal 150 in multiple encryption communication using token A as the encryption password (i.e., information shared between the user terminal 150 and the server system 100). Multiple encryption communication can be maintained through such protocol conversion.

The above describes one embodiment of the present invention, but these are merely examples for the purpose of explaining the present invention, and are not intended to limit the scope of the present invention to these embodiments. The present invention can also be implemented in various other forms.

For example, the personal authentication system described above may be an external system to a service system that provides services other than personal authentication and performs personal authentication on behalf of the service system, or it may be a service system that provides services to users who have been successfully authenticated (i.e., authenticated).

In addition, in the above explanation, the information provided by HTTP when a URL in a URL notification is specified is an OTP, but other types of information may be adopted instead of or in addition to the OTP. For example, "personal authentication" may be performed without an OTP (for example, with only authentication information such as an ID and password), and in communication after successful personal authentication, a token may be issued, the token may be sent to the user terminal, a URL notification may be sent to the user terminal, and information may be provided to the user terminal by HTTP when a URL in the URL notification is specified. In addition, in communication in the service system, communication may always be performed using the above-mentioned HTTP from a predetermined stage.

100: Server system, 150: User terminal

Claims

A token management unit, a WEB-IF (interface) unit, and an OTP (one-time password) management unit provided in a server system;
A token management unit provided in a user terminal having a WEB browser,
The token manager of the server system generates a token;
The WEB-IF unit of the server system transmits the generated token to the user terminal by HTTP,
The token management unit of the user terminal stores the token from the server system;
The OTP management unit of the server system associates the issued OTP required for user authentication with the generated token associated with the user;
The OTP management unit of the server system transmits a link notification addressed to a user, the link including an OTP link having a character string based on the token;
When the OTP link described in the issued link notification is specified,
The token management unit of the user terminal determines whether or not the token that is the basis of the character string of the specified OTP link matches the stored token;
If the result of the determination is positive, an HTTP request according to the OTP link is transmitted by the user terminal;
When the server system receives an HTTP request following the OTP link, the WEB-IF unit of the server system transmits an HTTP response of the OTP to the user terminal, and the WEB browser of the user terminal displays the OTP;
A requirement for successful authentication of the user is that the OTP entered by the user matches the OTP associated with the token with which the user is associated.
Identity authentication system.
the WEB-IF unit of the server system provides a first WEB page which is a WEB page for accepting input of information for personal authentication, and a second WEB page which is a WEB page for accepting input of an OTP;
At least one of the first web page and the second web page has the generated token;
2. The personal authentication system according to claim 1.
the server system includes an encryption unit and a server key;
the user terminal has an encryption unit and a user key;
the encryption unit of the server system encrypts target information, which is information to be transmitted to the user terminal via HTTP, using the server key and the server-side encryption password, which is the generated token, and the WEB-IF unit of the server system transmits first encrypted information, which is the encrypted target information, to the user terminal via HTTP;
the encryption unit of the user terminal encrypts the first encrypted information from the server system using the user key and the user-side encryption password which is the stored token, and the WEB browser of the user terminal transmits second encrypted information which is the encrypted first encrypted information to the server system via HTTP;
the encryption unit of the server system decrypts the second encrypted information from the user terminal by using the server key and the same password as the server-side encryption password, and the WEB-IF unit of the server system transmits the first encrypted information, which is the decrypted second encrypted information, to the user terminal by HTTP;
the encryption unit of the user terminal decrypts the first encrypted information from the server system using the user key and the same password as the user-side encryption password, thereby obtaining the target information;
3. The personal authentication system according to claim 1 or 2.
The target information is the OTP.
4. The personal authentication system according to claim 3.
the server system includes an encryption unit and a server key;
the user terminal has an encryption unit and a user key;
The encryption unit of the user terminal encrypts target information, which is information to be transmitted to the server system via HTTP, using the user key and a user-side encryption password, which is at least one of the stored token and an OTP from the server system, and the WEB browser of the user terminal transmits first encrypted information, which is the encrypted target information, to the server system via HTTP;
the encryption unit of the server system encrypts the first encrypted information from the user terminal using the server key and a server-side encryption password which is at least one of the generated token and the issued OTP, and the WEB-IF unit of the server system transmits second encrypted information which is the encrypted first encrypted information to the user terminal via HTTP;
the encryption unit of the user terminal decrypts the second encrypted information from the server system using the user key and the same password as the user-side encryption password, and the WEB browser of the user terminal transmits the first encrypted information, which is the decrypted second encrypted information, to the server system via HTTP;
the encryption unit of the server system decrypts the first encrypted information from the user terminal by using the server key and the same password as the server-side encryption password, thereby obtaining the target information;
3. The personal authentication system according to claim 1 or 2.
The target information is information input by a user to a web page displayed by the web browser of the user terminal.
6. The personal authentication system according to claim 5.
the server system includes an encryption unit and a server key;
the user terminal has an encryption unit and a user key;
a protocol of communication between the WEB browser of the user terminal and the WEB-IF unit of the server system transitions from a first HTTP to a second HTTP;
the second HTTP-compliant communication is a multiple encryption communication,
the target of the multiple encryption communication is at least a part of information transmitted from the WEB browser of the user terminal to the WEB-IF unit of the server system and information transmitted from the WEB-IF unit of the server system to the WEB browser of the user terminal,
the multiple encryption includes encryption by the encryption unit of the server system using the server key and a server-side encryption password, and encryption by the encryption unit of the user terminal using the user key and a user-side encryption password,
Both the encryption password on the server side and the encryption password on the user side are at least one of the token and information transmitted and received between the server system and the user terminal in multiple encryption communication using the token as an encryption password.
7. An authentication system according to claim 1.
A method for authenticating an individual by a server system that communicates with a user terminal having a web browser, comprising:
Generate a token,
Sending the generated token to the user terminal via HTTP;
Associating a user with the generated token;
Associating the issued OTP with the generated token associated with the user;
Sending a link notification to the user, the link including an OTP link having a character string based on the generated token;
When the user terminal determines that a token based on a character string of the specified OTP link on the issued link notification matches the stored token, an HTTP request according to the OTP link is received, and an HTTP response of the OTP is transmitted to the user terminal;
A requirement for successful authentication of the user is that the OTP entered by the user matches the OTP associated with the token with which the user is associated.
Authentication method.
A computer program for causing a user terminal having a web browser that communicates with the server system described in claim 1 to execute the operation of the token management unit described in claim 1.