JP4257339B2 - Password input device, control method and program for password input device - Google Patents

Description

  The present invention relates to a password input device that receives a password input by a user, a control method for the password input device, and a program.

  Currently, in various information processing apparatuses, user authentication processing for performing user authentication based on a password input by a user is performed. With the diversification of scenes where user authentication processing is performed, there are cases in which a password input device for inputting a password does not have a keyboard having keys corresponding to the characters that can be used for the password.

In such a case, a keyboard image with a limited number of keys to be displayed is displayed on the screen, and by accepting input of characters to be authenticated from the user through the touch panel, many character types can be used for the password. There is a technique for reducing the number of characters presented to the user at one time (see Patent Document 1).
JP-A-2005-107678

  However, the above technique is based on the assumption that the user selects an authentication target character from displayed characters using a coordinate input device such as a touch panel. Therefore, even with the above technique, passwords based on a large number of character types cannot be input using an operation means having a limited number of operation members such as buttons, such as a controller of a consumer game machine.

  On the other hand, when a user inputs any of a large number of character types using a controller of a game machine or the like, a list of a plurality of characters as input candidates and a pointer image pointing to any of the plurality of characters are displayed on the screen. There is a way to display. In this method, the user can select an input character from a plurality of characters by moving the pointer image in accordance with the user's operation on the direction key or the like. However, when this method is used for inputting a password, the user needs to be careful not to see the screen when inputting the password by a third party, and is troublesome when inputting the password.

  The present invention has been made in view of the above circumstances, and one of its purposes is to make it troublesome at the time of password entry even when the number of operation members provided in the operation means is limited. It is an object of the present invention to provide a password input device, a password input device control method, and a program capable of performing password authentication based on a large number of character types compared to the number of operation members while reducing the number of operation members.

  In order to solve the above problems, a password input device according to the present invention includes an operation unit including a plurality of operation members that receive an instruction operation from a user, and each of the plurality of input candidate characters with any one of the plurality of operation members. Input guide image display control means for displaying on the display means a character input guide image showing the correspondence relationship between the input candidate character acquisition for acquiring a plurality of characters including the authentication target character included in the password as the plurality of input candidate characters And an input character acquisition unit that acquires, as an input character, an input candidate character associated with the operation member on which the operation has been performed in response to a user operation on any of the plurality of operation members. Features.

  According to the above configuration, the character input guidance image indicating that the authentication target character included in the password is associated with one of the plurality of operation members is displayed, and the input character is displayed according to the operation on the operation member by the user. By acquiring, it is possible to accept the input of the character to be authenticated by the user even when there are more character types used for the password than the number of operation members. On the other hand, even if the displayed image can be viewed by a third party by displaying an image showing the correspondence between the plurality of input candidate characters including the authentication target character and the operation member as the character input guide image, The authentication target character included in the password can be made difficult to be known to a third party. As a result, it is possible to reduce the need to pay attention to the eyes of a third party when inputting the password, and to reduce the troublesomeness when inputting the password.

  Further, in the password input device, the input guidance image display control means displays a character input guidance image indicating a correspondence relationship between the plurality of operation members and the plurality of input candidate characters for each operation member, and The input character acquisition means may acquire a plurality of input candidate characters associated with the operation member on which the operation has been performed as input characters. According to this configuration, even if the image displayed on the display unit and the operation member operated by the user are simultaneously known to a third party, there are a plurality of input candidate characters associated with the operation member. , It can be made difficult to know which character is the character to be authenticated, and security can be improved.

  In the password input device, the input guide image display control unit may display a character input guide image indicating a correspondence relationship with each operation member for input candidate characters including a plurality of authentication target characters. . According to this configuration, the user can continuously input a plurality of authentication target characters in a state where one character input guide image is displayed. According to this configuration, it is possible to avoid switching the image displayed on the display unit according to the number of characters to be authenticated. Thereby, even if an image displayed on the display means is seen by a third party, the number of characters to be authenticated constituting the password can be made difficult to be known by the third party, and security can be improved.

  The password input device further includes means for acquiring a plurality of characters that do not include the authentication target character as the plurality of input candidate characters, and the input guide image display control means includes the authentication candidate as the input candidate character. Any one of the character input guide image that includes the target character and the character input guide image that does not include the authentication target character in the input candidate character, and a predetermined display other than the plurality of operation members It is good also as displaying on the said display means one by one according to the user's operation with respect to the operation member for sending. Further, in the password input device, the input character acquisition means may not acquire the input character when a user operation is performed on the display sending operation member. According to this configuration, the input character is acquired by receiving an operation on the display sending operation member by the user in a state where the character input guide image in which the authentication target character included in the password is not included in the input candidate character is displayed. It is possible to switch the screen display to a new character input guide image without performing it. Thereby, even if an image displayed on the display means is seen by a third party, the number of characters to be authenticated constituting the password can be made difficult to be known by the third party, and security can be improved.

  In the password input device, the input candidate character acquisition unit may include a plurality of characters acquired by the input candidate character acquisition unit as input candidate characters including the authentication target character in the past as a plurality of characters including the authentication target character. It is good also as acquiring the character determined based on a character. According to this configuration, by using the input candidate character determined according to the character used as the input candidate character in the past, the character displayed on the screen as the input candidate character can be viewed by a third party multiple times. In this case, it is possible to make it difficult for a third party to know the character to be authenticated, and security can be improved.

  The password input device control method according to the present invention is a password input device control method including an operation unit including a plurality of operation members that receive an instruction operation from a user, and each of a plurality of input candidate characters, A step of displaying a character input guidance image indicating a correspondence relationship with any of the plurality of operation members on a display unit; and a step of acquiring a plurality of characters including an authentication target character included in a password as the plurality of input candidate characters. And, in response to a user operation on any of the plurality of operation members, obtaining an input candidate character associated with the operation member on which the operation has been performed as an input character.

  The program according to the present invention is a program for controlling a password input device including an operation unit including a plurality of operation members that accepts an instruction operation from a user, and the plurality of operations for each of a plurality of input candidate characters. Input guide image display control means for displaying on the display means a character input guide image indicating a correspondence relationship with any of the members, and an input for acquiring a plurality of characters including an authentication target character included in a password as the plurality of input candidate characters Computer as input character acquisition means for acquiring as input characters candidate character acquisition means and input candidate characters associated with the operation member on which the operation has been performed in response to a user operation on any of the plurality of operation members Is made to function.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. A password input device 1 according to an embodiment of the present invention is, for example, a consumer game machine, and as illustrated in FIG. 1, a control unit 11, a storage unit 12, an operation unit 13, a display control unit 14, and communication The unit 15 is configured to be included. The password input device 1 is connected to the display device 2. Further, the password input device 1 is connected to the authentication server 2 via the communication network 3 so as to be able to perform data communication with each other. Here, the communication network 3 may be a local area network, for example, or may include a wide area network such as the Internet. The password input device 1 and the authentication server 2 connected via the communication network 3 constitute a user authentication system that performs user authentication based on the password input by the user as a whole.

  The control unit 11 is a CPU or the like, and operates according to a program stored in the storage unit 12. In the present embodiment, a character input guide image corresponding to information transmitted from the authentication server 4 is output to the display control unit 14, thereby causing the display device 2 to display the image. In addition, by receiving a control signal sent from the operation unit 13, information on input characters corresponding to a user operation is acquired. The acquired input character information is transmitted to the authentication server 4 to be used for the success / failure determination of the user authentication by the authentication server 4. An example of processing executed by the control unit 11 in the present embodiment will be described in detail later.

  The storage unit 12 is a computer-readable information storage medium that holds a program executed by the control unit 11, and includes at least one of a memory element such as a RAM and a ROM, a disk device, and the like. . The storage unit 12 also operates as a work memory for the control unit 11.

  The operation unit 13 includes a plurality of operation members such as buttons for receiving an instruction operation from the user, and outputs a control signal representing the content of the user instruction operation to each operation member to the control unit 11. Here, a specific example will be described in which the operation unit 13 is a controller of a consumer game machine. As shown in FIG. 2, the controller as the operation unit 13 includes gripping units 20R and 20L. The user grips these grips 20 with the left and right hands, respectively. A first operation unit 21, a second operation unit 22, and analog operation units 23 </ b> R and 23 </ b> L are provided at positions where the user can operate with each thumb while holding the grip unit 20.

  Here, the first operation unit 21 is provided with an upward direction key 21a, a downward direction key 21b, a right direction key 21c, and a left direction key 21d. The user can instruct a direction by using these direction instruction keys 21a, 21b, 21c and 21d, and is used for specifying an operation target on the screen, for example. Further, the second operation unit 22 includes a triangular button 22a provided with a triangular (“Δ”)-shaped mark, an X button 22b provided with a cross-shaped (“×”)-shaped mark, and a circle (“ A “）” button 22c provided with a shape marking and a rectangular button 22d provided with a rectangular (“□”) shape marking. These buttons 22a, 22b, 22c, and 22d are assigned to execute some processing according to the operation target specified by the direction instruction keys 21a, 21b, 21c, and 21d, for example.

  The analog operation portions 23R and 23L can be tilted with the point a as a fulcrum, and can be rotated around the rotation axis b passing through the fulcrum a in the tilted state. It has become. The analog operation parts 23R and 23L are configured to hold their positions in a state where there is no upright inclination as shown in FIG. Then, when the tilt operation is performed while pressing the analog operation unit 23R or the analog operation unit 23L, coordinate values (x, y) on the xy coordinates corresponding to the tilt amount and the tilt direction with respect to the reference position are detected. Is output to the control unit 11 as an operation output.

  The controller also includes a start button 24 for instructing the control unit 11 to execute a program, a select button 25 for instructing switching between various modes, and a mode selection switch 26. For example, when a specific mode (analog mode) is selected by the mode selection switch 26, the light emitting diode (LED) 27 is controlled to emit light, and the analog operation units 23R and 23L are in an operating state. When another mode (digital mode) is selected, the light emitting diode 27 is controlled to be turned off, and the analog operation units 23R and 23L are brought into a non-operating state.

  Further, the controller is provided with a right button 28 and a left button 29 at positions where the gripping portions 20R and 20L are gripped with the left and right hands, for example, at positions where they can be operated with the index finger of each hand. Each of the buttons 28 and 29 includes a first right button 28R1, a second right button 28R2, a first left button 29L1, and a second left button 29L2, which are provided side by side in the thickness direction of the controller.

  The display control unit 14 converts the image information output from the control unit 11 into a video signal and outputs the video signal to the display device 2. The display device 2 is, for example, a display device or a home television, and corresponds to the display means in the present invention. The display device 2 displays an image on the screen based on the image signal output from the display control unit 14.

  The communication unit 15 is a network interface, and transmits information to the authentication server 4 via the communication network 3 in accordance with an instruction from the control unit 11. The communication unit 15 receives information coming from the authentication server 4 via the communication network 3 and outputs the information to the control unit 11.

  The authentication server 4 is a server computer or the like, for example, holds password information, and authenticates the user using the password information. As a specific example, the authentication server 4 transmits a password input request to the password input device 1 via the communication network 3 when executing processing that requires user authentication. Then, the information on the input characters input by the user to the password input device 1 is acquired via the communication network 3. Furthermore, the authentication server 4 performs the authentication success / failure determination by collating the acquired input character information with the password information. Specifically, an example of information transmitted / received between the authentication server 4 and the password input device 1 in the present embodiment will be described later.

  Functionally, the password input device 1 includes an input guide image display control unit 31 and an input character acquisition unit 32 as shown in FIG. These functions can be realized, for example, when the control unit 11 executes a program stored in the storage unit 12.

  The input guidance image display control unit 31 acquires a plurality of input candidate characters. Then, for each of the input candidate characters, an image (character input guidance image) indicating a correspondence relationship with any of the plurality of operation members is output to the display control unit 14 to be displayed on the display device 2. . It is assumed that the input candidate characters indicated by the character input guide image displayed by the input guide image display control unit 31 when the user inputs the password include the authentication target characters included in the password.

  Specifically, for example, the input guidance image display control unit 31 acquires input candidate characters by accepting data including information on input candidate characters transmitted from the authentication server 4. When transmitting a password input request to the password input device 1, the authentication server 4 associates, for example, a plurality of randomly determined characters with each of the authentication target characters included in the password to be authenticated. Then, an input candidate character group including a plurality of input candidate characters is generated. Here, the authentication server 4 determines that the input candidate characters included in the input candidate character group are different from each other. In addition, the number of input candidate characters included in each input candidate character group is determined in advance according to the number of operation members provided in the operation unit 13 or the like. Then, the authentication server 4 transmits information on the number of input candidate character groups corresponding to the number of authentication target characters to the password input device 1 via the communication network 3.

  In this case, the password input device 1 does not necessarily need to identify which character is the authentication target character among the input candidate characters included in the transmitted input candidate character group. Thereby, the password input device 1 can accept password input while reducing the risk of password leakage. Further, the authentication server 4 may encrypt the input candidate character group information and transmit it via the communication network 3. Thereby, the risk of password leakage by the communication network 3 can be reduced.

  As a specific example, when the authentication target characters included in the password are four characters of “p”, “a”, “s”, and “s” in order, the authentication server 4 uses the input candidate characters including the input candidate characters including “p”. A group G1, an input candidate character group G2 including “a”, an input candidate character group G3 including “s”, and an input candidate character group G4 including “s” are generated. As an example, the authentication server 4 generates four input candidate character groups as illustrated in FIG. 4 and transmits them to the password input device 1.

  Further, the authentication server 4 may transmit not the information of the input candidate character group but the information of the authentication target character included in the password to the password input device 1. In this case, the input guide image display control unit 31 that has received the information on the authentication target character generates a candidate input character group by associating a plurality of characters with each authentication target character. Even in this case, the authentication server 4 may encrypt the information on the character to be authenticated and transmit it.

  Further, the input guidance image display control unit 31 performs a mapping process for determining a correspondence relationship with any one of the plurality of operation members for each of the input candidate characters included in the acquired input candidate character group. Here, as a specific example, eight input candidate characters included in the input candidate character group are designated as an upward direction key 21a, a downward direction key 21b, a right direction key 21c, and a left direction which are operation members used for password input. Assume that the direction instruction key 21d, the triangular button 22a, the x button 22b, the circle button 22c, and the rectangular button 22d are associated with each other. The input guidance image display control unit 31 may determine the correspondence relationship between the input candidate character and the operation member, for example, randomly or based on a predetermined condition. The input guidance image display control unit 31 may associate a plurality of input candidate characters with one operation member. An example of the user authentication process in this case will be described in detail later.

  Then, the input guide image display control unit 31 outputs a character input guide image indicating the determined correspondence relationship to the display control unit 14 to display on the display device 2. Specifically, for example, the character input guide image schematically represents the arrangement of each operation member on the operation unit 13 and also arranges input candidate characters associated with the vicinity of each operation member schematically represented. It is an image. FIG. 5 is a diagram illustrating an example of a character input guidance image for the input candidate character group G4 in FIG. In the example of FIG. 5, the character input guidance image is an image in which the input candidate characters included in the input candidate character group G4 are arranged on the image imitating the shape of the operation unit 13 shown in FIG. This character input guidance image includes an upward direction key 21a and “W”, a downward direction key 21b and “2”, a right direction key 21c and “p”, a left direction key 21d and “s”, and a triangular button 22a. And “6”, X button 22b and “q”, ○ button 22c and “4”, and rectangular button 22d and “i”, respectively.

  In addition, the input guide image display control unit 31 sequentially switches the character input guide images to be displayed on the display device 2 in accordance with a user operation on any of the plurality of operation members associated with the input candidate characters. I will do it. Specifically, the character input guide image based on the input candidate character group including the next authentication target character of the authentication target character included in the currently displayed character input guide image is displayed. For example, in the example of the input candidate character group shown in FIG. 4 described above, when a user operation is performed in a state where a character input guide image based on the input candidate character group G1 is displayed, the input guide image display control unit 31 newly inputs. A character input guide image based on the candidate character group G2 is displayed on the display device 2.

  For example, when a user operation is performed on the operation member associated with the input candidate character in a state where the character input guide image based on the last input candidate character group G4 is displayed, the input guide image display control unit 31 A dummy guide image may be displayed. Here, the dummy guide image is a character input guide image showing a correspondence relationship between input candidate characters not including the authentication target character and each operation member. For example, the input guidance image display control unit 31 acquires a dummy input candidate character group (dummy character group) by randomly determining a plurality of arbitrary characters. And the character input guidance image which shows the correspondence of each input candidate character contained in the said dummy character group and each operation member is displayed on the display apparatus 2 as a dummy guidance image. According to this method, the input guide image display control unit 31 continues the process of displaying the dummy guide images sequentially unless the user explicitly performs an instruction operation for instructing the end of password input. Thereby, it is possible to prevent a third party who tries to perform user authentication illegally from entering the password and to know the number of characters of the password.

  The input character acquisition unit 32 acquires, as an input character, a character associated with the operation member on which the operation has been performed in response to a user operation on any of the plurality of operation members provided in the operation unit 13. As a specific example, the input character acquisition unit 32 receives a control signal output by the operation unit 13 in response to a user's instruction operation in a state where the input guide image display control unit 31 displays a character input guide image. And the operation member which the user performed operation based on the said control signal is specified. Furthermore, the input character acquisition unit 32 acquires, as an input character, a character that is shown in association with the identified operation member in the character input guidance image currently displayed on the display device 2. For example, in the example of the character input guide image of FIG. 5 described above, when the user presses the up direction key 21a, the input character acquisition unit 32 uses the input candidate character “W” associated with the operation member as the input character. get. Further, when the left direction instruction key 21d is pressed, the input candidate character “s” is acquired as the input character.

  When the input character acquisition unit 32 determines that the password input has been completed, the input character acquisition unit 32 outputs the input characters acquired so far in order to the communication unit 15, thereby transmitting them to the authentication server 4. The authentication server 4 authenticates the user using the transmitted input characters. Here, as a method for the input character obtaining unit 32 to determine the end of the password input, for example, there is the following method. That is, when an input character is acquired in a state where a character input guide image based on the last input candidate character group is displayed, it is determined that the password input has been completed. In this case, the display of the dummy guide image by the input guide image display control unit 31 described above is not executed. Alternatively, the end of password input may be determined by an instruction operation that explicitly instructs the user to end password input. In this case, among the plurality of operation members provided in the operation unit 13, at least one operation member (input end operation member) that is not associated with the input candidate character is an instruction operation indicating the end of password input. It is supposed to be associated with Specifically, for example, the start button 24 is an input end operation member. When the user presses the start button 24 while the character input guidance image is displayed, the input character acquisition unit 32 determines that the password input operation by the user has ended.

  Next, an example of user authentication processing executed by the password input device 1 and the authentication server 4 will be described based on the flowchart of FIG. Here, an example will be described in which the password to be authenticated consists of four authentication target characters “p”, “a”, “s”, and “s” as in the above-described example.

  First, the authentication server 4 generates input candidate character groups G1, G2, G3, and G4 as illustrated in FIG. 4 based on each authentication target character included in the held password (S1). Then, the password input device 1 transmits the input candidate character group information generated in S1 together with the password input request (S2).

  The password input device 1 that has received the password input request transmitted by the authentication server 4 in S2 prompts the user to input a password, and acquires information on input characters input by the user. Specifically, first, the input guidance image display control unit 31 determines the correspondence between the input candidate characters included in the input candidate character group and each operation member based on one of the input candidate character groups acquired in S2. Mapping processing is performed, and a character input guide image indicating this correspondence is displayed on the display device 2 (S3). In this state, the input character acquisition unit 32 acquires information on the operation member operated by the user in accordance with the control signal input from the operation unit 13 (S4). When the operation member operated by the user acquired in S4 is an input end operation member (here, the start button 24), the input character acquisition unit 32 executes the process of S6. On the other hand, if the operation member is associated with another input candidate character, the input candidate character associated with the operation member is acquired as an input character (S5).

  Subsequently, the password input device 1 repeatedly executes the processes from S3 to S5 until the start button 24 is pressed. Here, the image displayed by the input guidance image display control unit 31 in the process of S3 is an image based on the input candidate character groups G1, G2, G3, and G4 acquired in S2 in order. Moreover, the character input guidance image displayed after the fifth time after displaying the character input guidance image based on all the input candidate character groups is a dummy guidance image based on the dummy character determined at random by the password input device 1. I will do it.

  When the operation member operated by the user acquired in S4 is the start button 24, the input character acquisition unit 32 receives an input character consisting of a character string arranged in the order in which the input characters acquired in S5 are acquired. By outputting the information to the communication unit 15, the information is transmitted to the authentication server 4 (S6). At this time, the password input device 1 may transmit the input character information encrypted.

  Subsequently, the authentication server 4 that has received the input character information transmitted by the password input device 1 in S6 determines whether or not the received input character information matches the stored password. (S7). And the information of a determination result is transmitted with respect to the password input device 1 (S8). The password input device 1 that has received the information transmitted in S8 presents the information to the user by, for example, displaying information based on the password determination result on the display device 2 (S9). Alternatively, when the authentication is successful as a result of the determination in S7, a process for a user who is correctly authenticated may be started.

  According to the user authentication process described above, even when the user inputs characters constituting the password by the operation unit 13 having fewer operation members than, for example, a keyboard for a general personal computer, Various character types can be used for passwords. In the present embodiment, since the input characters do not depend on the input method of the operation unit 13 or the like, not only uppercase letters, lowercase letters, and numbers illustrated in FIG. 4 but also kanji, katakana, hiragana, or special characters Any character such as a symbol can be used in the password. Furthermore, unlike the case of using a method such as a software keyboard that displays a list of characters that can be used for a password on the screen of the display device 2 and allows the user to select by moving the cursor, the characters are input by a simple operation for the user. be able to. Moreover, even if the video displayed on the screen when the password is entered is viewed by a third party, the password can be made difficult for the third party to know and the security can be improved.

  In addition, as described below, the password input device 1 according to the present embodiment displays a character input guide image indicating a correspondence relationship between a plurality of operation members and a plurality of input candidate characters for each operation member. It is good also as performing.

  According to this configuration, for example, the input guidance image display control unit 31 acquires the input candidate character group, and then associates the operation member with the input candidate character so as to associate a plurality of input candidate characters with one operation member. Determine the correspondence relationship. Then, a character input guide image indicating the determined correspondence is displayed on the display device 2. Specifically, the number of operation members associated with input candidate characters is k, and the maximum number of input candidate characters associated with each operation member is m. In this case, the input guidance image display control unit 31 acquires an input candidate character group including a maximum of (k × m) input candidate characters for each of the authentication target characters included in the password, and sets each input candidate character. Correspond to one of k operation members.

  As an example, the input guide image display control unit 31 causes the display device 2 to display a character input guide image as shown in FIG. In the example of FIG. 7, four input candidate characters are associated with each of the eight operation members.

  In a state in which such a character input guidance image is displayed, the user performs an operation on the operation member associated with the authentication target character included in the password, as in the above-described example. For example, in the example of FIG. 7, when the user wants to input the character to be authenticated “p”, the user presses the up direction key 21a. In this case, the input character acquisition unit 32 acquires, as input characters, a plurality of input candidate characters associated with the operation member operated by the user. Note that the input character acquisition unit 32 records the acquired input characters in association with information about how many times the user has acquired the input characters. Similarly to the above-described example, when it is determined that the input of the password has been completed by pressing the start button 24, for example, the acquired input character information is transmitted to the authentication server 4.

  In this case, the authentication server 4 determines whether or not the user authentication is successful as follows. That is, the first character to be authenticated of the password to be authenticated is included in the input characters acquired based on the first user operation included in the input character information received from the password input device 1. It is determined whether or not. Similarly, it is determined whether or not the nth character to be authenticated is included in the input characters acquired based on the nth user operation. When it is determined that all the authentication target characters are included in the corresponding input characters, it is determined that the authentication is successful. In other cases, it is determined that the authentication has failed.

  According to the above configuration, even if the image displayed on the screen of the display device 2 and the content of the instruction operation on the operation unit 13 by the user are known to the third party at the same time, the third party can easily enter the password. Cannot be specified. For example, even if the third party is informed that the user has pressed the up direction key 21a while the character input guidance image shown in the example of FIG. It is only understood that the target character is any one of “p”, “w”, “6”, or “a”, and it is impossible to specify what the authentication target character is. Thereby, security can be further improved.

  In this method, as the number m of input candidate characters corresponding to each operation member is increased, the risk of a password leaking when a user's operation is stolen can be reduced. However, when the value of m is increased, it becomes difficult to search for characters on the screen that the user is trying to input. In addition, an increase in the value of m may cause a problem that even if the user intends to input an incorrect character, it is determined that the character input as a result of authentication coincides with the password. Therefore, the password input device 1 uses the value of m determined based on the number of operation members provided in the operation unit 13, the required security level, the number of character types that can be used for passwords, and the like, The correspondence relationship with the candidate character may be determined.

  Next, a configuration for preventing leakage of the number of characters to be authenticated constituting the password will be described.

  When a general information processing apparatus accepts a password input from a user, an echo character such as “*” may be displayed on the screen according to the number of characters input by the user. However, in this embodiment, in order to make it difficult for a third party to know the number of characters to be authenticated included in the password, echo characters may not be displayed on the screen.

  Furthermore, in order to make it difficult for a third party to know the number of characters of the password, the password input device 1 according to the present embodiment may execute the following processing.

  For example, the input guide image display control unit 31 displays a character input guide image indicating the correspondence between each of the input candidate characters including two or more authentication target characters and any of the plurality of operation members. In this case, the authentication server 4 generates an input candidate character group by associating two or more authentication target characters with, for example, a plurality of randomly determined characters. Information that associates one or more input candidate character groups with the number of authentication target characters included in each input candidate character group is transmitted to the password input device 1. The input guide image display control unit 31 sequentially displays the character input guide images based on the respective input candidate character groups based on the information transmitted by the authentication server 4. Here, the number of authentication target characters included in one input candidate character group may be a predetermined number or a randomly determined number. Alternatively, the input candidate character group may include all of the authentication target characters included in the password.

  The input character acquisition unit 32 acquires an input character according to a user operation, as in the examples described above. However, in this case, every time an input character is acquired, the input guide image display control unit 31 is not necessarily updated by the input guide image display control unit 31, but the input character according to a user operation until a predetermined condition is satisfied. Continue processing to get. Here, the predetermined condition is to execute acquisition of input characters according to the user's operation as many times as the number of authentication target characters included in the input candidate character group shown in the character input guide image. .

  As a specific example, a case where the password is “pass” and the character input guide image displayed on the display device 2 by the input guide image display control unit 31 is as illustrated in FIG. 5 will be described. Here, assuming that the character input guide image of FIG. 5 is generated based on the input candidate character group including all the authentication target characters constituting the password, the input guide image display control unit 31 of FIG. After the character input guide image is displayed, the character input guide image is not displayed again. In this state, the user sequentially presses the upward direction key 21a, the upward direction key 21a, the right direction key 21c, the right direction key 21c, and the start button 24. In response to this operation, the input character acquisition unit 32 assigns “p”, “w”, “6”, and “a” to the third and fourth user operations in association with the first and second user operations, respectively. In association with each other, “h”, “8”, “s”, and “j” are acquired as input characters. Based on this input character, the authentication server 4 can determine that the password “pass” matches the input character acquired by the password input device 1.

  When the number of character types used in the password is equal to or less than the number (k × m) of the number k of input candidate characters associated with each operation member multiplied by the number k of operation members associated with the input candidate characters. The image display control unit 31 may use a character group composed of all character types used for a predetermined password as an input candidate character group. In this example, the input guide image display control unit 31 displays on the display device 2 a character input guide image indicating a correspondence relationship with any one of the plurality of operation members for each of the characters that may be used in the password. Let In this case, the input candidate character group includes all the authentication target characters constituting the password.

  According to the example described above, the user can input a plurality of authentication target characters with one character input guide image displayed on the display device 2. Thereby, it is possible to make it difficult for a third party who is viewing the display device 2 to know the number of characters of the password by the number of times the character input guide image is switched, and to improve security.

  Moreover, the input guidance image display control part 31 is good also as switching a character input guidance image based on a user's designation | designated. In this case, it is assumed that at least one operation member among the plurality of operation members included in the operation unit 13 is associated with the screen switching process. When the operation member associated with the screen switching process is operated by the user in a state where the character input guide image is displayed, the input guide image display control unit 31 operates the user with respect to the authentication server 4 so far. An input candidate character regeneration request for generating an input candidate character including an authentication target character to be input next, which is determined according to the number of input characters input according to the above, is transmitted. In response to the transmitted request, the authentication server 4 newly generates an input candidate character group including uninput authentication target characters and transmits the input candidate character group to the password input device 1. The input guide image display control unit 31 causes the display device 2 to display a new character input guide image indicating the correspondence between the input candidate characters included in the received new input candidate character group and each operation member. Note that when the operation member associated with the screen switching process is operated by the user, the input character acquisition unit 32 does not acquire the input character. According to this configuration, the user can arbitrarily adjust the number of screen switching in the course of the user authentication process by explicitly executing the screen switching. Thereby, it is possible to make it difficult for a third party to know the number of characters of the password, and security can be improved.

  Further, the input guide image display control unit 31 may display the dummy guide image on the display device 2 while sequentially displaying the character input guide images including the authentication target characters. Here, the dummy guide image is a character input guide image in which the input candidate character does not include the authentication target character as described above. In this case, among the plurality of operation members included in the operation unit 13, a predetermined operation member other than the operation member associated with the input candidate character is associated with the display feed process as the display feed operation member. To do. The display sending operation member may be the same as the operation member associated with the screen switching process in the above-described example.

  In this example, the input guidance image display control unit 31 performs character input including authentication target characters in the input candidate characters in response to a user operation on a plurality of operation members or display feed operation members associated with the input candidate characters. Either one of the guide image and the character input guide image (dummy guide image) that does not include the authentication target character in the input candidate characters is sequentially switched and displayed in a predetermined order. The order in which the character input guide images are displayed and the number of times the dummy guide images are displayed are determined at random, for example. In this case, all of the input candidate characters shown in the dummy guidance image are different from the authentication target character to be input next. According to this method, when the dummy guidance image is displayed, even if the user tries to input the next authentication target character, the authentication target character cannot be input because the authentication target character is not displayed on the screen. Therefore, the user performs an operation on the display feed operation member. In response to this operation, the input guide image display control unit 31 causes the display device 2 to display the next character input guide image. Note that when the user performs an operation on the display feed operation member, the input character acquisition unit 32 does not acquire the input character. According to this example, the password input device 1 displays the dummy guidance image one or more times during the password input process, even when the user inputs the same password, and displays it during the user authentication process. It is possible to change the number of times the character input guide image displayed on the device 2 is switched. Thereby, it is possible to make it difficult for a third party to know the number of characters of the password, and security can be improved.

  Next, another example of the mapping process in which the input guide image display control unit 31 associates the input candidate character with any of the plurality of operation members will be described.

  In the description so far, the input guidance image display control unit 31 associates the input candidate character with a randomly determined operation member among a plurality of operation members used for password input. The mapping process executed by the control unit 31 is not limited to this. For example, when the authentication server 4 transmits information on the character to be authenticated to the password input device 1, the input guide image display control unit 31 performs past user authentication processing (for example, a certain number of past times) determined based on a predetermined condition. In the user authentication process or the like, the operation member associated with each authentication target character is stored as mapping information. Then, when executing the mapping process, the input guide image display control unit 31 performs input based on past mapping information, for example, so as to associate the authentication target character with an operation member different from the operation member associated with the past. A correspondence relationship between the candidate character and the operation member is determined. Thereby, the operation member to be operated when the user inputs the password is different from the past, and the order of the operation members to be operated can be prevented from being patterned.

  In this case, the order of displaying the dummy guide images that need to be operated on the above-described display feed operation member may be determined in the same manner. That is, the password input device 1 stores the number of characters to be authenticated including the character input image that has been displayed in the past user authentication process after displaying the dummy guide image. The dummy guide images may be displayed in an order different from the order displayed on the screen, and the display feed operation member may be operated by the user.

  Next, another example of the input candidate character determination method will be described.

  In the description so far, the input candidate character group is generated by associating randomly determined characters with one or a plurality of authentication target characters, but the user authentication system according to the present embodiment inputs The method for generating the candidate character group is not limited to this. For example, the authentication server 4 uses the input candidate characters including the authentication target characters when the input guide image display control unit 31 displays the input candidate characters other than the authentication target characters included in the input candidate character group in the past. You may decide based on the character used as.

  For example, the authentication server 4 stores the input candidate characters included in the generated input candidate character group in the past user authentication processing (for example, a predetermined number of times of user authentication processing) determined based on a predetermined condition. I will do it. When the authentication server 4 generates an input candidate character group including the nth authentication target character, the authentication server 4 generates an input candidate character group including the same nth authentication target character in the past user authentication processing. An input candidate character group is generated by using at least one input candidate character used in the above as an input candidate character. According to this method, when the password input device 1 displays a character input guide image for inputting the nth character to be authenticated, the authentication target character is included among the input candidate characters indicated by the character input guide image. Two or more input candidate characters are in common with the input candidate characters indicated by the character input guide image displayed for inputting the same nth character to be authenticated in the past user authentication processing. As a result, even if the third party sees the character input guide image displayed on the display device 2 in the user authentication processing multiple times, the third party knows the authentication target character included in the password. Security can be improved.

  Similarly, in the example in which a plurality of input candidate characters are associated with one operation member described above, the password input device 1 is based on the input candidate characters associated with the same operation member as the authentication target character during the past user authentication processing. Thus, it is also possible to determine input candidate characters to be associated with the same operation member as the character to be authenticated during the current user authentication process. In this case, the password input device 1 receives information on the character to be authenticated included in the password from the authentication server 4 during the user authentication process. Then, an input candidate character group including the authentication target character is generated, and a correspondence relationship between each input candidate character and the operation member is determined so that a plurality of input candidate characters are associated with one operation member. At that time, the password input device 1 stores information on input candidate characters associated with the same operation member as the nth character to be authenticated during the past user authentication processing, and at least one character among the characters is stored. In this case, the nth authentication target character is associated with the operation member.

  In this case, the password input device 1 also associates input candidate characters associated with operation members other than the operation member associated with the authentication target character in common with one operation member in the past user authentication processing. A combination of input candidate characters to be associated with one operation member may be determined based on a combination of a plurality of input candidate characters. For example, the combination of a plurality of input candidate characters associated with one operation member may be the same as the combination of input candidate characters associated with another operation member in the previous user authentication process. As a result, even if a third party repeatedly views the image displayed on the screen of the display device 2 multiple times and the content of the instruction operation on the operation unit 13 by the user at the same time, the third It is possible to make it difficult for a person to know the character to be authenticated included in the password, and security can be improved.

  Further, the present invention is not limited to the above embodiment, and can be realized by various embodiments. For example, part or all of the processing that the authentication server 4 executes in the above description may be executed by the password input device 1. As a specific example, when the authentication server 4 transmits the authentication target characters constituting the password to the password input device 1, the password determination that the password input device 1 determines whether the input characters and the password match. It is good also as performing. Alternatively, the password input device 1 may hold the password by itself and execute the user authentication process alone.

It is a block diagram showing the structural example of the user authentication system containing the password input device which concerns on embodiment of this invention. It is a figure showing an example of the operation part with which the password input device which concerns on embodiment of this invention is provided. It is a functional block diagram showing the function of the password input device which concerns on embodiment of this invention. It is a figure showing an example of the input candidate character group which the password input device concerning an embodiment of the invention acquires. It is a figure showing an example of the character input guidance image which the password input device which concerns on embodiment of this invention displays. It is a flowchart which shows an example of the process performed by the password input device which concerns on embodiment of this invention. It is a figure showing another example of the character input guidance image which the password input device which concerns on embodiment of this invention displays.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Password input device, 2 Display apparatus, 3 Communication network, 4 Authentication server, 11 Control part, 12 Storage part, 13 Operation part, 14 Display control part, 15 Communication part, 20 Gripping part, 21 1st operation part, 22 2nd operation part, 23 analog operation part, 24 start button, 25 select button, 26 mode selection switch, 27 light emitting diode, 28, 29 button, 31 input guidance image display control part, 32 input character acquisition part.

Claims (7)

An operation means comprising a plurality of operation members for receiving an instruction operation from a user;
For each of a plurality of input candidate characters, a character input guidance image showing a correspondence relationship with any of the plurality of operation members, wherein the plurality of operation members and a plurality of input candidate characters for each operation member Input guidance image display control means for displaying a character input guidance image indicating the correspondence on the display means;
Input candidate character acquisition means for acquiring a plurality of characters including an authentication target character included in a password as the plurality of input candidate characters;
Input character acquisition means for acquiring, as input characters, a plurality of input candidate characters associated with the operation member on which the operation has been performed in response to a user operation on any of the plurality of operation members;
A password input device comprising: An operation means comprising a plurality of operation members for receiving an instruction operation from a user;
For each of the plurality of input candidate characters, an input guidance image display control unit that causes a display unit to display a character input guidance image indicating a correspondence relationship with any of the plurality of operation members;
Input candidate character acquisition means for acquiring a plurality of characters including an authentication target character included in a password as the plurality of input candidate characters;
Means for acquiring a plurality of characters not including the authentication target character as the plurality of input candidate characters ;
Input character acquisition means for acquiring, as an input character, an input candidate character associated with the operation member on which the operation has been performed in response to a user operation on any of the plurality of operation members;
It includes,
The input guidance image display control means is any one of the character input guidance image that includes the authentication target character in the input candidate character and the character input guidance image that does not include the authentication target character in the input candidate character. and in response to user's operation for a given display advancement operation member other than said plurality of operation members or operating member, a password input apparatus for causing sequentially displayed on the display means. The password input device according to claim 2 ,
The password input device, wherein the input character acquisition unit does not acquire an input character when a user operation is performed on the display sending operation member. In the password input device according to any one of claims 1 to 3,
The password input device, wherein the input guide image display control means displays a character input guide image indicating a correspondence relationship with each operation member for an input candidate character including a plurality of authentication target characters. In the password input device according to any one of claims 1 to 4 ,
The input candidate character acquisition unit is a character determined based on a plurality of characters acquired by the input candidate character acquisition unit as input candidate characters including the authentication target character in the past as a plurality of characters including the authentication target character. A password input device characterized by acquiring the password. A control method of a password input device including an operation means including a plurality of operation members that accepts an instruction operation from a user,
For each of a plurality of input candidate characters, a character input guidance image showing a correspondence relationship with any of the plurality of operation members, wherein the plurality of operation members and a plurality of input candidate characters for each operation member Displaying a character input guidance image indicating the correspondence on the display means;
Acquiring a plurality of characters including an authentication target character included in a password as the plurality of input candidate characters;
In response to a user operation on any of the plurality of operation members, obtaining a plurality of input candidate characters associated with the operation member on which the operation has been performed as input characters;
A method for controlling a password input device. A program for controlling a password input device including an operation unit including a plurality of operation members for receiving an instruction operation from a user,
For each of a plurality of input candidate characters, a character input guidance image showing a correspondence relationship with any of the plurality of operation members, wherein the plurality of operation members and a plurality of input candidate characters for each operation member Input guidance image display control means for causing the display means to display a character input guidance image indicating the correspondence ,
The input candidate character acquisition means for acquiring a plurality of characters including the authentication target character included in the password as the plurality of input candidate characters, and the operation is performed according to a user operation on any of the plurality of operation members. Input character acquisition means for acquiring a plurality of input candidate characters associated with the operation member as input characters;
A program characterized by causing a computer to function.

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