JP6493973B2 - Character string input method and program - Google Patents

Description

  The present invention relates to a method for inputting a character string such as a password and a password, and a program therefor.

  In recent years, the damage of stealing passwords and passwords by viruses has been increasing. For example, a spyware called a key logger that steals input information from a keyboard has been known for a long time. In recent years, an increasing number of phishing scams that pretend to be legitimate e-mails or websites from financial institutions and scam PINs, passwords, and credit card numbers.

  As one of the methods for preventing the fraud of passwords and passwords, the inventors have `` erased '' characters from the character string on the input screen without inputting the characters from the keyboard. Has been proposed (see Patent Document 1). According to this method, it is possible to provide an effective countermeasure against the peeping of the input screen from another person and the above-mentioned key logger.

  On the other hand, online banking can also be used to enter a PIN or password by displaying the software keyboard on the screen without using a physical keyboard and specifying the position of the keys to be entered on the software keyboard with a mouse. Introduction is progressing at sites. According to this method, since a physical keyboard is not used, it is effective for the countermeasure against the keylogger as described above.

Japanese Patent No. 5687368

  However, there is also new spyware that steals input information to the software keyboard. When this type of spyware enters a user's personal computer or the like, it waits for a software keyboard window to appear, and when that window becomes active, it captures the personal computer screen each time the mouse is clicked. By looking at this captured image (screen shot), you can tell which key the user clicked on the software keyboard, so you can steal passwords.

  The input method of Patent Document 1 does not use a mouse or a software / keyboard. However, if the screen being input is continuously captured by the screen capture type spyware as described above, which character is erased? As it turns out, there is still a possibility of password theft. Screen capture spyware is not limited to personal computers, and there is a concern that touch-panel type terminals such as smartphones and tablet terminals that have spread rapidly spread to attack targets. Therefore, the input method of Patent Document 1 is also compatible with a touch panel display, and needs to be protected against spyware as described above.

  Moreover, in the input method of Patent Document 1, the erased character, that is, a character string such as a password is temporarily stored in the terminal, and then transmitted to the authentication device (authentication server). When the contents of the memory are analyzed by spyware, or when encryption such as SSL (Secure Sockets Layer) is decrypted, the leakage of the password cannot be completely prevented.

  Therefore, in the present invention, the invention of Patent Document 1 is improved, it is compatible with a touch panel type input device, can be protected against screen capture type spyware, and a secret character string such as a password is stored in the internal memory. An object of the present invention is to provide a character string input method that does not store the character string on the network without storing it.

  In order to solve the above problems, the character string input method of the present invention provides the following solution.

One aspect of the present invention is:
(1) A character string input method for preventing a third party from illegally acquiring a character string input by a user, the step of accepting start of input of the character string from the user; Determining a character string display rule that is synchronized between a terminal device used by the user and a transmission destination device that is a transmission destination of the character string; and a screen of the terminal device according to the determined character string display rule Displaying one or more character strings for each character type, detecting that one character is designated by the user from each of the displayed character strings, and the designated character. And deleting the display of the character string from the screen of the terminal device and the character string from which the designated character has been deleted. And executes the steps of: transmitting to.

  (2) The character string has a personal identification number, password, account number, credit card number, telephone number, birthday, insurance card number, license number, Juki net number, My Number, or other confidentiality. It may be a character string.

  (3) In addition, the terminal device displays one or more character strings for each character type on the logical screen, and when the actual screen of the terminal device is smaller than the logical screen, the terminal screen is scrolled. The character string of the logical screen may be displayed.

  (4) In addition, the terminal device may delete the character string deleted on the screen in response to another character string being deleted on the screen, or the user may read the character string on the screen. The erased character string may be redisplayed according to the designation.

  (5) In addition, the character string pattern according to the character string display rule is based on the date and time information when inputting the character string from the terminal device, and the number of characters in the character string and the arrangement of the characters for each character type. It may be changed.

  (6) The character string pattern according to the character string display rule is based on the number of characters in the character string for each character type based on the description of the document that can be acquired at the same time by both the terminal device and the transmission destination device. The character sequence may be changed.

  (7) Further, it may be possible to input a plurality of adjacent characters in the character string by designating a range of the character string.

  (8) The character string input method may be applied to a part of the input character string.

  (9) According to another aspect of the present invention, there is provided a program for preventing a character string input by a user from being illegally acquired by a third party, wherein (1) to (8) A computer is caused to execute the method described in any one of the above.

  According to the present invention, it is compatible with a touch panel type input device, can be protected against screen capture type spyware, and the character is stored on the network without storing a secret character string in the internal memory. It is possible to provide a new character string input method in which no string is transmitted.

It is a block diagram which shows the outline of the computer system which concerns on embodiment of this invention. It is a figure which shows an example of PIN code input operation which concerns on embodiment of this invention. It is a figure for demonstrating the general input method of the password containing several character types. It is a figure for demonstrating the password input screen which concerns on embodiment of this invention. It is a figure which shows an example of password input operation which concerns on embodiment of this invention. It is a figure which shows an example of password input operation which concerns on embodiment of this invention. It is a figure which shows an example of password input operation which concerns on embodiment of this invention. It is a figure which shows the processing flow of the terminal device of the character string input method which concerns on embodiment of this invention. It is a figure which shows the example of the variation of the character string pattern which concerns on embodiment of this invention. It is a figure which shows the modification of the variation of the character string pattern which concerns on embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail with reference to the accompanying drawings. Note that the same number is assigned to the same element throughout the description of the embodiment.

(Functional configuration)
FIG. 1 is a block diagram showing an outline of a computer system according to an embodiment of the present invention. The computer system includes an authentication server 100 connected to a network 300. The authentication server 100 is a transmission destination device that is a transmission destination of a character string such as a password input by a user. The network 300 may be an arbitrary computer network, but in the following description, as a typical example, the network 300 will be described.

  The authentication server 100 is a general computer configured with a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), and the like in hardware. The authentication server 100 includes an authentication function that permits access to the Web server 110 that configures a Web site on the Internet, and may be configured as a single server with the Web server 110. The authentication server 100 includes a communication unit 101 that performs communication control via the network 300, and a user information storage unit 102 that stores registration information of a user of a Web site that provides the service, and the service desired by the user Authentication process to access the.

  A stationary terminal device 200 or a portable terminal device 210 possessed by a user is connected to the network 300. The stationary terminal device 200 is a non-portable terminal such as a desktop PC. Functionally, a communication unit 201 that performs communication control, a storage unit 202 that includes a RAM, an HDD, and the like, operations of a keyboard, a mouse, and the like An input unit 203 and a display unit 204 such as a liquid crystal display are provided. It is assumed that the display unit 204 supports a touch panel type display.

  A portable terminal device 210 is connected to the network 300 by wireless communication. The portable terminal device 210 is a smartphone, a tablet terminal (slate terminal), a small notebook PC, or the like, and includes a wireless communication unit 211 that controls wireless communication, an SSD (Solid State Drive) that stores programs and setting data, and a RAM It is assumed that a storage unit 212 configured by the above, a physical switch 213 such as a power button and a volume button, and a touch panel display unit 214 are provided. The portable terminal device 210 performs wireless communication with the nearest base station 400 and communicates with the authentication server 100 connected to the network 300. Since the portable terminal device 210 is required to be downsized, the screen size of the display unit 214 (touch panel) is about 4 to 10 inches, which is considerably smaller than the screen size of the stationary terminal device 200. . Hereinafter, the stationary terminal device 200 is referred to as a stationary terminal, and the portable terminal device 210 is referred to as a portable terminal. In addition, both may be referred to simply as a terminal device.

  The Web site provides services to users (members) who have signed a use contract in advance, and each member has a login ID such as a contractor number and a user ID, and a personal identification number and password as an authentication server. 100 is registered. Some websites also allow member email addresses to be used as login IDs. Since the personal identification number is a password composed only of numerals, unless otherwise specified below, the term “password” includes the personal identification number.

  The login ID and password are stored as a database in the user information storage unit 102 of the authentication server 100. A member who intends to use a service provided on the Web site makes a login request using his / her own terminal device connected to the network 300. In response to this login request, the authentication server 100 displays a dedicated login screen on the terminal device and requests input of a login ID and password. If the login ID and password match the registration information, the user is authenticated as a legitimate user. Further, it is assumed that software (dedicated application) that controls communication with the authentication server 100 is installed in advance in the terminal device.

(Password input operation)
The basic concept of the present invention is a character string input method for preventing a third party from illegally acquiring a character string input by a user. A character string input device or a character string input system is also available. This can be included. Here, as a specific example, a case where a personal identification number or password is input on a touch panel display will be described. FIG. 2 is a diagram illustrating an example of a password input operation according to the embodiment of the present invention. Here, in order to explain the basic concept of the present invention in an easy-to-understand manner, a case of inputting a numeric password, that is, a personal identification number, which is the simplest example will be described.

  FIG. 2A is an example in which a login screen for net banking is displayed using a general smartphone. The user inputs an ID number such as a contractor number or a store number plus an account number and a personal identification number from this screen. In this example, the password is entered after entering the contractor number (here, “2015”). However, since the contractor number only has a different number of digits, the same method is used. Can do.

  First, when the password field is touched (tapped) on the screen shown in FIG. 2A, a plurality of rows as shown in FIG. 2B are displayed. The tap operation is an operation of touching the screen for a moment by lightly tapping the screen with a finger or a pen. The tap operation is used for operations such as selecting an item from a menu and pressing a button. This corresponds to a click (left click) in mouse operation. Hereinafter, when simply touching, this tap operation is indicated.

  The number of lines to be displayed corresponds to the number of digits of the personal identification number, and here is four lines. In this example, the numbers in each row are arranged in order, such as 0, 1, 2, 3,..., But the order of the numbers may be in any order. Moreover, the arrangement of numbers may be different for each row. However, at least one number from 0 to 9 must be included in each line.

  When “2” which is the first number of the personal identification number is touched on the screen of FIG. 2B, the touched number is erased from the sequence of the row as shown in FIG. The entire line is erased from the screen. At this time, only the number sequence “01345789” excluding “2” deleted from the original number sequence is stored in the memory inside the terminal. Next, when “0” is touched on the screen of FIG. 2C, “0” is deleted from the sequence of the row, and the entire row is deleted from the screen. At this time, only the numerical sequence “123456789” excluding “0” is stored in the memory inside the terminal. Similarly, when “1” is touched on the screen of FIG. 2D and “5” is touched from the screen of FIG. 2E, the touched numbers are erased from the sequence of each row, and the entire row Disappears from the screen in order. At this time, in the internal memory, only the numerical sequences “02345789” and “012346789” are stored, and the password “2015” is not stored.

  Then, when a confirmation operation (in this example, a “login” button is touched) that signifies the completion of the input of the personal identification number on the screen in which all the numbers in FIG. A number sequence obtained by removing the touched number from the original number sequence is transmitted without transmitting the personal identification number itself. That is, in this example, “0134578989 123456789 0345456789 0123346789” (actually no space is included) is transmitted to the server. Here, the arrangement of numbers in each row is synchronized according to a predetermined rule that only the terminal and the server can understand, and the server compares the number sequence transmitted from the terminal with the number sequence displayed on the terminal according to this predetermined rule. By doing so, the input personal identification number can be extracted from the transmitted character string. In the above example, the input is made in order from the top line on the screen, but any line may be used.

  Further, in preparation for spyware that simultaneously records the touch position of a finger or the like on the touch panel and captures the screen, for example, a screen displaying a sequence of numbers as shown in FIG. The entire screen is erased once before the screen is displayed. And after erasing, the original screen is displayed. In this way, it is possible to make it difficult to capture a screen that displays the entire character string. Alternatively, a means for detecting that screen capture has been performed (for example, detecting that a screen shot command has been issued to the OS (Operating System) of the terminal) is provided, and before screen capture is executed. You may make it erase | eliminate the display of the whole screen.

  In the example of FIG. 2, for ease of explanation, each number is only one per line, and the arrangement of numbers in each line is the simplest and simplest pattern. According to a predetermined “synchronization rule”, the arrangement of numbers (number sequence) is made different each time. Here, for example, the “synchronization rule” may be determined according to the “rule ID” generated by the date and time when the personal identification number field on the login screen is touched. Specifically, a predetermined conversion is performed on the date / time / minute / second number (referred to as date / time information) when the PIN number field is touched to generate a “display character string ID”, which is displayed on the screen according to the display character string ID. Ensure that the sequence of numbers displayed is specified.

  It is assumed that the same date / time information is also transmitted to the server side at the time of authentication, and the server generates a “display character string ID” based on the date / time information by the same conversion logic, and identifies a corresponding sequence pattern. Then, the password entered by the user can be extracted by comparing the generated sequence pattern with the sequence pattern transmitted from the terminal. Alternatively, the “synchronization rule” may add a predetermined conversion to a unique ID (for example, a terminal ID) registered by the user. Needless to say, the “synchronization rule” is periodically changed between the server and the terminal.

  Also, if the line displayed on the input screen contains a line that contains the same sequence as a part of the numbers in the PIN, touch the screen with your fingertip. It is also possible to input a plurality of adjacent numbers in a character string at a time by touching at that position after specifying the range by moving the finger as it is or by touching it lightly. For example, since the sequence of “01” in the personal identification number “2015” is included in each row of FIG. 2B, the range of “0” and “1” is designated by a slide operation in any row. If touched at that position, 0 and 1 can be input simultaneously. The lines displayed on the input screen do not always have numbers arranged in the same order, but there are a plurality of columns of numbers, so if there are about two characters, there is a high probability of matching with a considerable probability.

  By doing so, the numbers entered on the touch panel are not displayed on the screen of the terminal, so you can not only peep from others, but even if the terminal is infected with screen capture spyware, The entered numbers are never stolen. Further, since the personal identification number itself is not temporarily stored in the terminal, it is not transmitted over the network.

  In addition to the personal identification number, the above-mentioned character string input method is not limited to the contractor number (customer number), account number, credit card number, telephone number, birthday, insurance card number, license number, Juki net number, Furthermore, the present invention can be applied to input of confidential numbers such as personal numbers that are unnecessarily unknown to others, such as My Number scheduled to be introduced in October 2015.

(Entering passwords that include multiple character types)
Although FIG. 2 illustrates the case where only numbers such as a password are input, the input method of the present invention can also be applied to input of passwords and IDs including characters other than numbers such as English letters and symbols. The password is stronger in security by combining multiple character types such as alphabetic characters (including uppercase and lowercase letters), symbols, etc., rather than a number-only password, so the password policy specifies the minimum number of characters and character types. There are many websites.

  FIG. 3 is a diagram for explaining a conventional method for inputting a password including a plurality of character types in a terminal such as a smartphone or a PC. In general, on a login screen for a terminal with a small screen size, displaying a keyboard of all character types on the screen to input multiple character types makes the characters very small, like the smartphone input screen shown in the figure, A keyboard switching key 10 is used to switch and input a plurality of keyboards. This software keyboard is provided on the OS or application side of the smartphone. However, in order to enter a password with a mixture of letters, numbers, and symbols, it is troublesome because it is necessary to switch the keyboard many times. For this reason, some terminals having a large screen size display a plurality of keyboards side by side, as in the PC input screen shown separately.

  The present invention proposes an input method that does not require different screens depending on the screen size as described above. FIG. 4 is a view for explaining a password input screen according to the embodiment of the present invention.

  In this input method, a “character string” is defined in which all or one character used as a password is arranged as a character string for each character type. As shown, the character string is arranged on the logical screen. Since the actual screen of the terminal varies depending on the screen size, it can be scrolled up, down, left and right on the logical screen by a slide operation. Of course, if the screen size is large, the entire logical screen may be displayed on the real screen. It goes without saying that the real screen can be enlarged or reduced by a pinch operation (operation that touches the screen with two fingers and then pinches) / stretch operation (operation that touches the screen with two fingers and then moves the fingers away from each other). By doing this, all the character strings on the logical screen can be displayed on the real screen, and even if the real screen such as a smartphone is smaller than the logical screen, passwords containing many character types can be switched to a keyboard, etc. Can be entered without.

  The character string is not necessarily matched with the “line” on the logical screen, and a plurality of character strings may be arranged on one line on the logical screen like the numerical character string shown in the figure. In the figure, character strings are arranged in the order of numbers, uppercase letters, lowercase letters, and symbols, but the arrangement is not limited to this arrangement, and the arrangement of characters in the character string may be arbitrary. The character string needs to include at least one character of all characters of the character type, but a plurality of the same characters may be included in one character string. Also, katakana, hiragana, etc. may be added as the character type. Furthermore, not only half-width characters but also full-width characters may be added. For example, the answer to the “secret question”, which is a type of password, may require double-byte characters.

  Hereinafter, a method for inputting a password including a plurality of character types will be described in detail. 5A to 5C are diagrams illustrating an example of a password input operation according to the embodiment of the present invention. In this example, a PC screen with a large screen size is used, and the actual screen and the logical screen will be explained. However, even if the real screen and the logical screen do not match, basically the same operation is performed by adding a scroll operation. It is. In addition, in order to make the figure easy to see, there are three character strings of numbers in one line on the screen, and character strings of other character types are only one line on the screen.

  Here, assuming that the password to be input is, for example, “ABc — 123”, the password input operation will be specifically described with reference to the screens (A) to (L) in FIGS. 5A to 5C in order. When the password input field on the login screen (not shown) is touched, one or more character strings are displayed for each character type as shown in screen (A). Here, as in the case of the password, the displayed character string pattern is synchronized between the server and the terminal according to a predetermined rule.

  In order to input the password “ABc — 123”, first, “A” of an uppercase character string is touched on the screen (A). In the figure, the touched position is indicated by an underline. However, the underline is not actually displayed. As shown in the screen (B), the entire uppercase letter line including the touched “A” is deleted, and “A” is excluded. The character string “BCDE...” Is stored. (The same shall apply hereinafter.) Next, when “B” is input, since the line including “B” is erased on the screen (B), the erased line is touched once to be displayed again in the original state. After that (the state of the screen (C)), it is assumed that “B” is touched. Then, when “B” is touched, the capital letter line is erased again (screen (D) state).

  In this way, since the character string once erased on the screen can be displayed again, it is not necessary to display the character string on the screen by the number of characters input for each character type. Without the redisplay function, for example, to input “ABCdefGH”, it is necessary to display at least 5 lines of uppercase characters and 3 lines of lowercase characters. If there is a function, each line should be displayed. Therefore, the redisplay function is particularly effective for an input device having a small screen size.

  Note that the touch for redisplaying the erased line as in the above screen (B) is necessary only when there is only one character string. A touch is usually not necessary. For example, in the above example, if there are two uppercase letters, only one line can be deleted by touching “A”, so “B” can be touched directly from the other line. Further, for example, when inputting “C”, the line “A” is automatically redisplayed at the same time as the line “B” is erased, so “C” is changed from the redisplayed line. Touch it. Of course, even when there are a plurality of lines of the same character type, if the deleted line is touched, the line is redisplayed.

  Turning to the description of FIG. 5B. The screen (E) is in a state after touching “B”, but “c” to be input next is a lower case character, so a lower case line is displayed. Therefore, “c” can be touched as it is. When “c” is touched, the touched lowercase letter line is erased as shown in the screen (F), but at the same time, the previously erased uppercase letter line is automatically redisplayed. In the screen (G) in this state, the symbol “_” to be input next can be touched as it is. When “_” is touched, the symbol line is deleted as before.

  Moving to FIG. 5C, when “1” is touched next on the screen (I), the touched “1” row is erased as shown in the screen (J), and at the same time, “_” erased first. Will be displayed again. In this example, since there are three number lines, even if the touched “1” line is deleted, the other number lines are not deleted. Therefore, “2” to be input next can be touched as it is from the displayed number row. Touch “2” to delete the number line. At this time, the previously deleted number row of “1” may remain erased, but may be automatically redisplayed. When redisplayed, the screen (K) is displayed.

  On the screen (K), touch “3”, which is the last character of the password, using one of the displayed number lines. As a result, the touched “3” row is erased on the screen (L), but the previously erased “2” row may be displayed again. Finally, when a confirmation operation such as a login button is touched, a character string excluding characters touched (erased) in the above-described series of procedures is transmitted to the server.

  As in the case of the PIN, the screen that displays the sequence of characters is temporarily displayed before the screen is displayed in preparation for spyware that simultaneously records the touch position on the touch panel and captures the screen. Try to erase. Then, the original screen is displayed. Alternatively, a means for detecting that the screen capture has been performed may be provided so that the display of the entire character string screen is erased immediately before the screen capture is executed.

(Processing flow)
FIG. 6 is a diagram showing a processing flow of the terminal device of the character string input method according to the embodiment of the present invention. FIG. 6 summarizes the input procedure described above as a flow of processing steps executed by the terminal.

  When accepting the start of input of a character string such as a password from the user, the terminal first determines a character string display rule to be synchronized with the authentication server 100 (generally a transmission destination device) in step S10. The character string display rule is a rule used this time, and is determined every time. Subsequently, in step S11, a character string (character string pattern) according to the determined character string display rule is displayed on the logical screen. A specific example of the character string display rule determination is as described above.

  Next, in step S12, the terminal checks whether or not a character in the displayed character string is specified, that is, whether or not a character in the character string displayed on the screen is touched. If the character in the character string is not touched (step S12: N), it is checked whether a predetermined cancel operation has been performed. If the cancel operation has been performed (step S20: Y), all data is erased. Then, the input process is finished. If no cancel operation has been performed (step S20: N), the process returns to step S12.

  If a touch of a character in the character string is detected in step S12 (step S12: Y), the process proceeds to step S13, and the display of the character string including the touched character is erased from the logical screen. At this time, if there is a character string already erased, the line may be displayed again. If any part of the already erased character string is touched, the entire character string is displayed again.

  In step S14, the character string excluding the touched (erased) character is stored. As described above, the touched character itself is not stored in the terminal because it is a character constituting a password. In step S15, it is checked whether a predetermined confirmation operation has been performed, such as a touch on a transmission button or a login button.

  If it is detected in step S15 that a confirmation operation has been performed (step S15: Y), the process proceeds to step S16 to check whether the minimum number of characters specified as a password has been input. Step S16: N), after displaying an error in step S17, re-input is prompted. If an error occurs more than a predetermined number of times, the input operation is terminated.

  If the input of the minimum number of characters is confirmed in step S16 (step S16: Y), the process moves to step S18, and the character string excluding the touched (erased) character in each character string is the authentication server 100 (destination device). ). When the transmission is completed, the password input process is terminated.

(Example of character string pattern)
FIG. 7 is a diagram showing an example of variations of the character string pattern according to the embodiment of the present invention. As already described, the character string pattern displayed on the logical screen is synchronized (shared) between the terminal and the server, but an example of a simple character string pattern is shown below.

  FIG. 7A shows a basic character string pattern in which a plurality of character strings (here, three lines) are arranged in order for each character type. A plurality of character strings may be included in one line of the logical screen.

  FIG. 7B shows a change in the arrangement of characters in the character string. In this example, among the numeric strings B11 to B13, B11 starts from 1, but B12 starts from 4, and B13 starts from 8. The sequence of numbers may be in descending order instead of ascending order. Moreover, among the English capital letter strings (B21 to B23), B21 is arranged in the order of normal alphabets, but B22 is arranged in the reverse order starting from Z. B23 is arranged in the normal order starting from H. The same applies to the lowercase letters B31 to B33.

  In FIG. 7C, the numeric strings C11 to C13 are arranged at random. However, each number appears at least twice. The uppercase character string C22 is a 26-letter alphabet divided in half between M and N, and M and N are alternately extracted from the group of M and N, one character at a time, and arranged. Further, C23 is obtained by applying the above arrangement method to C22. In this example, the same applies to the lowercase letter strings C31 to C33, but other arrangements are naturally possible. In this way, there are almost infinite character string patterns, but what is required is that the rules for arranging characters are synchronized between the terminal and the server.

(Modification of character string pattern)
FIG. 8 is a diagram showing a variation of the character string pattern variation according to the embodiment of the present invention. The character string pattern can be generated from a description of a meaningful “document” instead of a simple character string as shown in FIG. However, this document is a document that can be acquired at the same time by both the terminal device and the transmission destination device.

  For example, FIG. 8A employs the numbers in the stock column of an electronic newspaper as a character string pattern. By defining in advance between the server and the terminal whether the stock data at that time and the data of the brand are used as the character string display rule, a character string (only numbers) displayed on the logical screen of the terminal can be generated. Moreover, it can be changed every day.

  FIG. 8B employs English electronic news as a character string pattern. If the electronic news at that time and its page or line are used as a character string display rule, it is defined in advance between the server and the terminal, and the character string (only letters and numbers) displayed on the logical screen of the terminal Can be generated. Moreover, it can be changed every day.

  Further, FIG. 8C employs a document such as a mail, a business letter, or the like mixed with Japanese, numbers, and English letters as a character string pattern. If a large number of such documents are collected, and an ID is assigned to define a character string display rule between the server and the terminal in advance, a character string displayed on the logical screen of the terminal can be generated. Such a document includes not only English characters and numbers but also various character types, so that there is a possibility that double-byte characters can be used (although the characters that can be used are limited). For example, in response to a secret question “What is your mother's birthday?”, You can enter “May 7” directly in double-byte characters without converting kana-kanji, or “Grandfather ’s hometown name For example, “Yamanashi Prefecture” can be entered.

  In the above description, the personal identification number and the password have been described as the character string that needs to be concealed. However, as described above, the character string input method of this embodiment is not limited to the personal identification number, but the contractor number (customer number). ), Account number, credit card number, telephone number, birthday, insurance card number, license number, Juki Net number, My Number, and other numbers related to personal information can also be applied. When the number of characters to be input is large (for example, a credit card number), the character string input method according to the embodiment of the present invention is applied to only a part of the character string (for example, the first four digits or the last four digits). Then, other characters may be input by a normal method. This is because security can be secured even if it is applied to only a part. Of course, the present invention can be applied to various login IDs and user IDs including character types other than numbers in addition to passwords.

  Further, the transmission destination device that is the transmission destination of the input character string may be a device that does not have an authentication function. For example, the password of the previously sent file is simply sent to the destination device. In the above description, the input device is a touch panel, but a display that is not a touch panel type may be used. In that case, “touch” in the above description may be read as “mouse click button pressed” or “move with cursor keys and press enter button”.

(Effect of embodiment)
As described above, according to the embodiment of the present invention, a character string that can be protected against screen capture type spyware and that requires confidentiality in the internal memory is also stored on the network. It is possible to provide a character string input method in which a sequence is not transmitted.

  In addition to the PIN, this string input method can be used for contractor number (customer number), account number, credit card number, phone number, birthday, insurance card number, license number, Juki Net number, My The present invention can also be applied to numbers or other confidential character strings (various login IDs and user IDs including other numbers related to personal information and character types other than numbers).

  In addition, since character strings are displayed on the logical screen, even a terminal with a small screen size can be used to scroll through the actual screen, so that characters that require many character types can be used without switching the keyboard. Even if it exists, all the characters that can be input can be displayed.

  In addition, since the character string once erased on the screen can be displayed again, it is not necessary to display the character string on the screen by the number of characters to be input for each character type. This is particularly effective for a terminal device having a small screen size.

  Further, since the synchronization rule between the terminal device and the destination device is changed based on the date and time information at the time of input, the character string pattern for displaying the character string spreads almost infinitely, even if the character string (password) transmitted to the destination device Even if a character string from which characters such as are deleted is decrypted, the character string that was originally displayed is not easily understood, so that it is difficult to decrypt a password or the like.

  In addition, since a character string pattern can be generated based on the description of a document that can be shared by both the terminal device and the transmission destination device, variations of the character string pattern can be further expanded, making it difficult to decrypt a password or the like. .

  Also, by specifying the range of the character string, it is possible to input a plurality of adjacent characters in the character string, so that the same character sequence as the character sequence to be input in a part of the displayed character string If there is a line, input operation becomes easy.

  Moreover, you may make it apply this character string input method only to a part of character string to input. If the character string to be input is long, security is ensured even if the character string input method is applied to only a part of the character string.

  As mentioned above, although this invention was demonstrated using embodiment, it cannot be overemphasized that the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. Further, it is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

10 Keyboard switching key 100 Authentication server 101 Communication unit (authentication server side)
102 User Information Storage Unit 110 Web Server 200 Stationary Terminal Device 201 Communication Unit (Stationary Terminal Device Side)
202 Storage unit (stationary terminal device side)
203 Operation Input Unit 204 Display Unit 210 Portable Terminal Device 211 Wireless Communication Unit 212 Storage Unit (Portable Terminal Device Side)
213 Physical switch 214 Touch panel 300 Network 400 Base station

Claims (9)

A string input method for preventing a third party from illegally acquiring a string entered by a user,
Receiving a start of input of the character string from the user;
Character string display rule used this time out of predetermined rules for synchronizing the character string pattern displayed on the terminal device used by the user and the character string pattern displayed on the transmission destination device which is the transmission destination of the character string A step of determining
Displaying one or more character strings for each character type on the screen of the terminal device according to the determined character string display rules;
Detecting that one character is designated by the user from each of the displayed plurality of character strings;
Erasing the designated character from the character string including the character and erasing the display of the character string from the screen of the terminal device;
Transmitting the character string from which the designated character is erased to the destination device;
A character string input method characterized in that the computer executes.   The character string is a personal identification number, password, account number, credit card number, telephone number, birthday, insurance card number, license number, Juki net number, my number, or other character string having confidentiality. The character string input method according to claim 1.   The terminal device displays one or more character strings for each character type on the logical screen, and when the actual screen of the terminal device is smaller than the logical screen, the characters on the logical screen are scrolled by the actual screen. The character string input method according to claim 1, wherein the character string can be displayed.   The terminal device is a character string deleted on the screen, in response to another character string being deleted on the screen, or in response to the user specifying the character string on the screen. The character string input method according to any one of claims 1 to 3, wherein the erased character string is displayed again.   The character string pattern according to the character string display rule changes the number of characters and the arrangement of characters in the character string for each character type based on date and time information when inputting the character string from the terminal device. The character string input method according to any one of claims 1 to 4.   The character string pattern according to the character string display rule is based on the description of documents that can be acquired at the same time by both the terminal device and the transmission destination device, and the number of characters and the arrangement of characters in the character string for each character type. 6. The character string input method according to claim 1, wherein the character string is changed.   The character string according to any one of claims 1 to 6, wherein it is possible to input a plurality of adjacent characters in the character string by specifying a range of the character string. input method.   The character string input method according to any one of claims 1 to 7, wherein the character string input method is applied to a part of a character string to be input.   A program for preventing a third party from illegally obtaining a character string input by a user, wherein the computer executes the method according to any one of claims 1 to 8. A featured program.