JP2021170757A - Authentication verification system, device to be authenticated, authentication device, authentication verification method, authentication verification program, computer readable recording medium, and recorded apparatus - Google Patents

Abstract

To achieve secure authentication addressing vulnerability and attacks with simple processing.SOLUTION: A device to be authenticated 1 comprises: a transmission unit 14 that transmits, to an authentication device 2, an authentication request including encryption information repeatedly in an authentication period; an encryption unit 13 that encrypts unique information and a verification value with a cipher key to generate encryption information; an acquisition unit 11 that generates the unique information; a verification unit 15 that generates the verification value to verify if verification of the authentication device is proper one after the verification; and a storage unit 12 that stores the generated verification value. The authentication device 2 comprises: a receiving unit 21 that repeatedly receives, in the authentication period, the authentication request including the encryption information encrypted with the cipher key transmitted from the device to be authenticated 1; a decryption unit 23 that decrypts the encryption information to acquire decryption information; an authentication unit 24 that determines whether the device to be authenticated 1 is proper by using the plurality of authentication requests received in the authentication period including the encryption information that has been successfully decrypted, and after the determination of authentication, transmits verification data including the verification value to the device to be authenticated 1; and an output unit 25 that outputs a result of determination made by the authentication unit.SELECTED DRAWING: Figure 1

Description

The present invention relates to an authentication verification system, a device to be authenticated, an authentication device, an authentication verification method, an authentication verification program, a computer-readable recording medium, and a recording device.

Conventionally, there is known a system capable of performing authentication using a personal mobile terminal such as a smartphone and making payment using a credit card or the like. With such a system, the user can pay for goods, services, and the like by using his / her own personal mobile terminal (see, for example, Patent Document 1).

Special Table 2017-501620

In such authentication, in order to improve user convenience and reduce the processing load, it is required to enable authentication by simpler processing. On the other hand, it is also required to be able to realize secure authentication against vulnerabilities such as decompilation and attacks of smartphones while preventing spoofing.

The present invention has been made to solve the above problems, and is an authentication verification system, an authenticated device, an authentication device, an authentication verification method, an authentication verification program, and an authentication verification system capable of realizing secure authentication by a simple process. The purpose is to respond to vulnerabilities such as reverse compilation and attacks of smartphones in providing computer-readable recording media and recording devices.

In order to achieve the above object, the authentication verification system of the present invention is an authentication system including an authenticated device for receiving authentication and an authentication device for authenticating the authenticated device.
The authenticated device is a transmitter that repeatedly sends an authentication request including encryption information to the authentication device within the authentication period, and an encryption unit that generates encryption information by encrypting unique information and verification values with an encryption key. It is provided with an acquisition unit that generates unique information, a verification unit that generates a verification value and verifies whether the authentication is valid after the authentication of the authentication device, and a storage unit that stores the generated verification value. The authentication device repeatedly receives an authentication request including encryption information encrypted by an encryption key sent from the authenticated device within the authentication period, and decrypts the encryption information to acquire decryption information. Using the decryption unit and multiple authentication requests received within the authentication period, including the decrypted encryption information, it is determined whether the device to be authenticated is valid, and after the authentication determination, the verification data including the verification value is authenticated. It includes an authentication unit that transmits to the device and an output unit that outputs a determination result by the authentication unit.

With such a configuration, it is possible to transmit a plurality of authentication requests including each of the encrypted information in which the plurality of unique information is encrypted to the authentication device. Then, using the plurality of authentication requests, the authentication device can realize secure authentication by a simple process. In addition, as a countermeasure against the theft of the encryption key by an attacker, a mechanism for verifying the validity of the authentication will be introduced here, which will make it possible to further enhance the security.

Further, in the authentication verification system according to the present invention, the verification value may include the time when the verification value is generated and either a random number value or a hash function value.

With such a configuration, even if the encryption key is stolen, it is possible to easily obtain a verification value including information that is difficult for an attacker to estimate.

Further, in the authentication verification system according to the present invention, the encryption key may be a common key encryption key.

With such a configuration, when a key with a different common key encryption is used for each authenticated device, the attacker receives the authentication request transmitted from the legitimate authenticated device and sends the received authentication request. Only attacks by sending to the authentication device can be performed. Therefore, it becomes easier to detect that an attack has taken place.

Further, in the authenticated device according to the present invention, the verification unit may check whether the verification value stored in the storage unit and the verification value transmitted from the authentication device match to determine whether the verification value is valid.

With such a configuration, the validity of authentication can be verified by a simple process.

Further, the authentication verification system according to the present invention further
After the authentication of the authentication device, the verification value from the authentication unit is received and transmitted to the verification unit of the authenticated device, and the authentication result and the verification result are communicated with the authenticated device and the authentication device in order to receive the verification result. It is provided with a system server including a line communication unit for the purpose and a server authentication unit that controls the behavior of the system according to the authentication and verification results.

With such a configuration, it is possible to collate with the user data on the system server, and it is possible to promptly take measures such as notifying the illegally used user and suspending the use.

Further, in the authentication device according to the present invention, the authentication unit compares the verification values included in the plurality of decryption information acquired from the plurality of authentication requests received during the authentication period, and if no consistency is found. In addition, it may be determined that the authenticated device is not valid.

With such a configuration, by confirming the validity of the verification value itself, in some cases, the existence of an attacker can be detected more quickly without waiting for the confirmation of the authenticated side.

Further, in the authenticated device according to the present invention, the transmission unit may transmit the unique information and the verification value by different means.

With such a configuration, the amount of information to be transmitted can be reduced. For example, the transmission frequency of the verification value can be made smaller than the unique value to reduce the load on the system.

Further, in the authentication device according to the present invention, the receiving unit may intermittently receive the authentication request.

With such a configuration, the load related to receiving the authentication request can be reduced, and the power consumption of the authentication device can be reduced.

Further, the authentication verification method according to the present invention is an authentication verification method for verifying the authentication of the authenticated device in an authentication system including an authenticated device to be certified and an authentication device that authenticates the authenticated device. Then, the authenticated device repeatedly sends an authentication request including the encrypted information to the authenticated device within the authentication period, and the authenticated device encrypts the unique information and the verification value with the encryption key to obtain the encrypted information. The step of generating unique information, the step of the authenticated device generating unique information, the step of the authenticated device generating a verification value, and the step of verifying whether or not the authentication was valid after the authentication of the authentication device, and the step of being authenticated. A step in which the device saves the generated verification value, and a step in which the authentication device repeatedly receives an authentication request including encryption information encrypted by an encryption key sent from the authenticated device within the authentication period. , The authenticated device uses a step of decrypting the encrypted information to obtain the decrypted information and a plurality of authentication requests received within the authentication period including the encrypted information that the authenticated device can decrypt. It includes a step of determining whether or not it is valid and transmitting verification data including a verification value to the authenticated device after the authentication determination, and a step of the authentication device outputting a determination result by the authentication unit.

According to the authentication verification system, the authenticated device, the authentication device, the authentication verification method, the authentication verification program, the computer-readable recording medium, and the recording device according to the present invention, the smartphone has vulnerabilities such as reverse compilation by simple processing. It is possible to realize secure authentication corresponding to sex and attacks.

A block diagram showing a configuration of an authenticated device, an authenticated device, and a system server according to an embodiment of the present invention. A flowchart showing the authentication operation of the authenticated device according to the same embodiment. A flowchart showing the authentication operation of the authentication device according to the same embodiment. A flowchart showing the operation of the system server according to the same embodiment. A flowchart showing the verification operation of the authenticated device according to the same embodiment. A flowchart showing the verification operation of the authentication device according to the same embodiment. The figure for demonstrating the transmission / reception of the authentication request in the same embodiment. The figure which shows an example of the configuration of the computer system in the same embodiment.

Hereinafter, the authentication verification system, the authenticated device, the authentication device, the authentication verification method, the authentication verification program, the computer-readable recording medium, and the recording device according to the present invention will be described using embodiments. In the following embodiments, the components and steps having the same reference numerals are the same or correspond to each other, and the description thereof may be omitted again. The authenticated device according to the present embodiment transmits a plurality of authentication requests including encrypted information obtained by encrypting a plurality of unique information to the authentication device. Further, the authentication device according to the present embodiment authenticates the authenticated device by using a plurality of authentication requests transmitted from the authenticated device. Further, the authenticated device according to the present embodiment transmits a verification value to the authentication device. The authentication device according to the present embodiment verifies the authentication by the authenticated device via the system server using the received verification value as verification data.

FIG. 1 is a block diagram showing the configurations of the authenticated device 1, the authentication device 2, and the system server 3 according to the present embodiment. The authenticated device 1 according to the present embodiment includes an acquisition unit 11, a storage unit 12, an encryption unit 13, a transmission unit 14, a verification unit 15, and a line communication unit 16. The authentication device 2 according to the present embodiment includes a receiving unit 21, a storage unit 22, a decoding unit 23, an authentication unit 24, an output unit 25, and a line communication unit 26. The system server 3 includes a server authentication unit 35 and a line communication unit 36. The authenticated device 1 may be, for example, a mobile information terminal having a communication function such as a smartphone, a tablet terminal, a PDA (Personal Digital Assistant), a notebook computer, a transceiver, or any other device. The authentication device 2 may be, for example, an automatic ticket gate, a gate for entering a venue such as an event, a vending machine, a control device for locking / unlocking the door of a hotel or a conference room for rent, a cash register, or the like. , A mobile information terminal having a communication function such as a smartphone. The system server 3 may be, for example, a server system installed on the cloud or may be installed in the authentication device 2. In the present embodiment, the case where the authenticated device 1 and the authenticated device 2 are mobile information terminals having a communication function will be mainly described. Note that FIG. 1 shows a case where one authenticated device 1 and one authenticated device 2 communicate with each other, but this may not be the case. Communication may be performed between the plurality of authenticated devices 1 and one authentication device 2. The communication is usually wireless communication.

First, the authenticated device 1 according to the present embodiment will be described.
The acquisition unit 11 acquires unique information. Each unique information may be, for example, different information. In this case, when the acquisition unit 11 acquires a plurality of unique information, the plurality of unique information will be different from each other. The unique information is encrypted, included in the authentication request, and transmitted, as described below. Therefore, when each unique information is different information, it can be said that the unique information is information unique to the authentication request. In addition, information usually composed of unique information and non-unique information (for example, information in which the upper bit is unique and the lower bit is not unique) is, as a result, unique information. Become. Therefore, unique information may thus be composed of unique information and non-unique information. In order to distinguish between the unique information and the unique information included in the unique information, the unique information included in the unique information may be referred to as a "unique part" below. In addition, non-unique information included in unique information may be referred to as "non-unique part". The non-unique part is information that cannot always be said to be unique information, and may be information that can change for each authentication request, such as location information described later.

The unique information may include, for example, a random number value, a count value, a time, a one-time password, or other unique information. The random number value may be generated by using, for example, a random number table or a function for generating a random number. The count value may be, for example, a value obtained by incrementing or decrementing a numerical value at predetermined intervals. When different unique information is used for each authentication request, it is preferable that the random number values and count values do not overlap. The time may be, for example, hours, minutes, seconds, minutes, seconds, or the like acquired from a clock unit (not shown). Further, when different unique information is used for each authentication request, it is preferable that the accuracy of the time is shorter than the transmission interval of the authentication request described later. By doing so, for example, the unique information can be the information unique to the authentication request. For example, when the transmission interval of the authentication request is about 10 milliseconds, the accuracy of the time may be 1 millisecond. When duplicated unique information may be used for a plurality of authentication requests, duplicated random numbers and counts may be used, and the time accuracy is longer than the transmission interval. May be good. Even in this case, as will be described later, since it is necessary to send a plurality of authentication requests corresponding to different unique information within the authentication period, such a plurality of authentication requests can be transmitted. It is preferable that unique information is acquired.

The acquisition unit 11 may generate unique information or may receive it from other components or devices. When the unique information is composed of a unique part and a non-unique part, the acquisition unit 11 acquires a unique part such as a random number value, a count value, a time, and a one-time password, and the unique part and its own device Unique information may be generated by using a non-unique part such as the ID of the authenticated device 1 which is the ID, the ID of the authentication device 2 of the transmission destination, and the position information of the authenticated device 1 which is the own device. The ID of the own device may be read from the storage unit 12 and used, for example. Further, the ID of the authentication device 2 at the transmission destination may be included in, for example, a transmission instruction described later, or may be read from the storage unit 12 and used. The position information of the own device may be acquired by the position acquisition unit, as will be described later. Further, the acquisition unit 11 may receive unique information from, for example, the authentication device 2. In that case, challenge-response authentication is performed by transmitting an authentication request including encrypted information obtained by encrypting the unique information from the authenticated device 1 to the authentication device 2. In this case, the authentication device 2 may generate the above-mentioned unique information. The acquisition unit 11 may receive, for example, a unique portion from the authentication device 2 and use the unique portion to generate unique information. In this case as well, challenge-response authentication can be performed using the unique portion included in the unique information.

In the storage unit 12, for example, the ID of the authenticated device 1 is stored. This ID is an identifier of the authenticated device 1 and is information unique to the authenticated device 1. Further, the storage unit 12 may store, for example, a key for common key cryptography, which will be described later, an ID which is an identifier of the authentication device 2, and the like. When the unique information includes a random number value or a count value, the storage unit 12 stores a random number table or function for acquiring the random number value, the latest count value for generating the count value, and the like. May be good.

The process of storing information in the storage unit 12 does not matter. For example, the information may be stored in the storage unit 12 via the recording medium, the information transmitted via the communication line or the like may be stored in the storage unit 12, or The information input via the input device may be stored in the storage unit 12. The storage unit 12 is preferably realized by a non-volatile recording medium, but may be realized by a volatile recording medium. The recording medium may be, for example, a semiconductor memory, a magnetic disk, an optical disk, or the like.

The encryption unit 13 encrypts the unique information and the verification value generated by the verification unit 15 described later with the encryption key to generate the encryption information. The encryption key may be, for example, a common key encryption key, or a public key of public key encryption corresponding to the authentication device 2 to which the authentication request is sent. When the encryption key is a common key cryptographic key, the common key cryptographic key may be a key unique to the authenticated device 1 or a common key unique to the authentication device 2. , The common key unique to the pair of the authenticated device 1 and the authentication device 2 may be used. In this case, the key of the common key encryption is different for each authenticated device 1. Further, as will be described later, the authentication device 2 also holds the key of this common key cryptography. When the encryption key is the public key of the public key cryptography, the public key of the public key cryptography of the transmission destination authentication device 2 may be included in, for example, a transmission instruction described later. The unique information may be encrypted with an encryption key common to the system, and this encryption key may be a common key, a public key, and a private key.

The transmission unit 14 repeatedly transmits an authentication request including the encryption information generated by the encryption unit 13 to the authentication device 2 within the authentication period. It is assumed that a plurality of authentication requests including each of the encrypted information in which the plurality of unique information is encrypted are transmitted within the authentication period. As described above, for example, when each unique information is different information, the encrypted information in which the different unique information is encrypted is included for each authentication request transmitted from the legitimate authenticated device 1. .. On the other hand, for example, when the unique information is duplicated, at least two authentication requests transmitted from the legitimate authenticated device 1 may include the encrypted information in which the same unique information is encrypted. .. Even in this case, a plurality of authentication requests corresponding to different unique information shall be transmitted within the authentication period. When a plurality of authentication requests sent during the authentication period include encrypted information in which the same unique information is encrypted, for example, the number of authentication requests including encrypted information in which the same unique information is encrypted is fixed. You may be. For example, a predetermined number of authentication requests include encrypted information in which the same unique information is encrypted, and the unique information corresponding to the encrypted information differs for each predetermined number of authentication requests. May be good. Further, the authentication request may include information other than the encrypted information. For example, the ID of the authenticated device 1 that is the source of the authentication request may be included in the authentication request. Further, it is desirable that each verification value corresponding to the encrypted information includes different verification data for each authentication request transmitted from the legitimate authenticated device 1. The authentication request and the verification value corresponding to the encrypted information may have different transmission means.

The verification unit 15 generates a verification value for verification after authentication. The verification value includes the time when the verification value is generated and a value such as a random number. The generated verification value is encrypted by the encryption unit 13, transmitted from the transmission unit 14 to the authentication device 2, and decrypted. It is transmitted from the line communication unit 26 as verification data to be described later, and is received by the line communication unit 16 via the system server 3. The verification unit 15 again verifies whether the verification value is transmitted by the authenticated device 1 itself. For example, the consistency is confirmed, such as whether the values such as the time when the verification value is generated and the random number transmitted from the authentication device 2 match the stored ones. It should be noted that it may be confirmed whether or not only the values such as random numbers stored in the period corresponding to the time when the verification value is generated match. In addition, it may be verified whether the authentication was used by the user. The verification value is sent each time it is authenticated. Further, it may be stored in a storage unit 12 or the like for a certain period of time, for example, one day, and the stored content may include a verification value. The verification unit 15 transmits the verified verification result to the system server 3. The value included in the verification value may be a random number or a cryptographic hash function value having some cryptographic property. Further, in order to save the amount of data stored in the authenticated device 1, only the generated time is transmitted so as to be different for each transmission, and the value such as the random number generated as the verification value does not differ for each transmission and is 1 second. It may be different by thinning out at regular intervals such as. At this time, as the verification value stored in the authenticated device 1, only the time when the verification value is generated, which is the update timing of the value such as the thinned out random number, may be stored. Note that there is information that overlaps with the unique information and the verification value, and when transmitting in the same packet, the overlapping data may be omitted.

The line communication unit 16 may be used for communicating with the system server 3 or may be used for other purposes. In the communication with the system server 3, information necessary for maintaining the system, such as verification data including verification values, verification results, own ID, and encryption key, may be communicated. It is desirable that the line communication unit 16 and the line communication unit 36 of the system server 3 are constructed with a dedicated line, and the communication means may be, for example, a mobile line network or a wired line network.

The certification period is usually a predetermined time length. The authentication period may start from the transmission of the first authentication request. Therefore, for example, the transmission unit 14 may start timing by the timer from the transmission of the first authentication request, and may end the transmission of the authentication request when the predetermined authentication period elapses. The authentication period is not particularly limited, but may be, for example, a time in the range of about 200 milliseconds to 10 seconds. As will be described later, since the authentication process in the authentication device 2 is not started until the authentication period ends, it is preferable that the authentication period is short. Therefore, the authentication time is preferably 3 seconds or less, and more preferably 1 second or less. The transmission unit 14 may start transmitting the authentication request when, for example, the authenticated device 1 receives a predetermined transmission instruction. The transmission instruction may be, for example, a beacon transmitted from a transmitter arranged near the authentication device 2.

The transmission unit 14 usually repeatedly transmits an authentication request at predetermined time intervals. The time interval may be, for example, constant or indefinite. In the former case, the time interval may or may not be set. Further, even if the time interval is indefinite, the average time interval may be set. For example, when the authentication request is communicated by Bluetooth Low Energy (LE), the time interval is indefinite, but the average time interval is fixed. In any case, the time interval is equal to or greater than the minimum communication interval defined by the communication standard for transmitting the authentication request by the transmission unit 14. Further, for example, even when the authentication device 2 performs intermittent reception, it is preferable that at least one of the plurality of authentication requests is transmitted so as to be received by the authentication device 2. be. Therefore, for example, the transmission cycle of the authentication request may be different from the reception cycle of the authentication device 2, and the authentication request may be transmitted at random transmission intervals. Further, the number of authentication requests transmitted by the transmission unit 14 during the authentication period may or may not be fixed. Even in the latter case, the authentication period is fixed, and the number of authentication requests sent within the authentication period, or the range of the number, is usually determined by sending the authentication requests at predetermined time intervals. It will be decided.

The wireless communication standard to which the transmission unit 14 transmits the authentication request does not matter. The authentication request may be communicated by, for example, low power consumption of Bluetooth (hereinafter, also referred to as "BLE"), or may be communicated by BR (Basic Rate) / EDR (Enhanced Data Rate) of Bluetooth. Often, it may be communicated by wireless LAN (IEEE802.11), may be communicated by IEEE802.5.4 such as ZigBee®, or may be communicated by other wireless communication standards. It is preferable that the authentication request is transmitted and received by short-range wireless communication such as BLE, Bluetooth BR / EDR, and wireless LAN. In the present embodiment, a case where communication is performed by the authentication request BLE will be mainly described.

The transmission unit 14 may transmit the authentication request by broadcasting or may communicate by unicast, for example. Since the authentication request can be transmitted without specifying the communication partner, it is preferable to transmit the authentication request by broadcasting. In the present embodiment, the case where the transmission unit 14 transmits the authentication request by broadcasting will be mainly described.

The transmission unit 14 may or may not include a wireless transmission device (for example, an antenna) for performing transmission. Further, the transmission unit 14 may be realized by hardware, or may be realized by software such as a driver for driving a transmission device.

Next, the authentication device 2 according to the present embodiment will be described.
The receiving unit 21 repeatedly receives the authentication request including the encrypted information encrypted by the encryption key transmitted from the authenticated device 1 within the authentication period. The source of the authentication request is usually the authenticated device 1 described above. On the other hand, as will be described later, the attacker's device receives the authentication request transmitted from the authenticated device 1 and transmits the received authentication request again, or obtains unique information independently and encrypts the information. It is also possible to generate an authentication request containing the encrypted information. In that case, the receiving unit 21 cannot determine whether the authentication request is transmitted from the legitimate authenticated device 1 or the attacker's device at the time of receiving the authentication request. Therefore, the device that has transmitted the authentication request will be referred to as the authenticated device 1. Then, as will be described later, after the plurality of authentication requests are received, the authentication unit 24 uses the authentication requests to determine whether the source is the original authenticated device 1, that is, the legitimate authenticated device 1. , The attacker's device, that is, the unjustified authenticated device 1.

The receiving unit 21 may intermittently receive the authentication request. Intermittent reception may mean that the period for receiving information and the period for not receiving information are alternately repeated. For example, when the authentication request is transmitted by broadcast by BLE communication, such intermittent reception will be performed. Power consumption can be reduced by performing intermittent reception. When intermittent reception is performed, for example, the length of the period for receiving information and the length of the period for not receiving information may be constant or indefinite. In the present embodiment, a case where the receiving unit 21 performs intermittent reception will be mainly described.

The receiving unit 21 may or may not include a wireless receiving device (for example, an antenna) for performing reception. Further, the receiving unit 21 may be realized by hardware, or may be realized by software such as a driver that drives the receiving device.

The storage unit 22 stores the decryption key. For example, when the encryption key is a key of common key cryptography, the decryption key is the key of the common key cryptography. In this case, the decryption key (common key cryptographic key) may be stored in the storage unit 22 for each authenticated device 1. The storage unit 22 may store a plurality of key correspondence information including, for example, the ID of the authenticated device 1 and the key of the common key encryption of the authenticated device 1 identified by the ID. Further, for example, when the encryption key is the public key of public key cryptography, the decryption key is a private key paired with the public key of the public key cryptography. When the unique information includes a random number value or a count value, the storage unit 22 stores a random number table or function for acquiring the random number value, the latest count value for generating the count value, and the like. May be good. Further, the storage unit 22 may store information such as a threshold value of the number of receptions and a reception interval in which the probability of reception is lower than the threshold value, which is used in the processing described later.

The process of storing information in the storage unit 22 does not matter. For example, the information may be stored in the storage unit 22 via the recording medium, the information transmitted via the communication line or the like may be stored in the storage unit 22, or The information input via the input device may be stored in the storage unit 22. The storage unit 22 is preferably realized by a non-volatile recording medium, but may be realized by a volatile recording medium. The recording medium may be, for example, a semiconductor memory, a magnetic disk, an optical disk, or the like.

The decryption unit 23 decrypts the encryption information using the decryption key and acquires the decryption information. For example, when the decryption key is a common key encryption key and the authentication request includes the ID of the authenticated device 1 that is the source of the authentication request, the decryption unit 23 is associated with the ID. The key of the common key encryption may be read from the storage unit 22, and the encrypted information may be decrypted by using the read common key encryption key. Further, for example, when the decryption key is a secret key, the decryption unit 23 may read the secret key from the storage unit 22 and decrypt the encrypted information using the read secret key. The decrypted information in which the encrypted information included in the authentication request transmitted from the legitimate authenticated device 1 is decrypted becomes the unique information and the verification value. Therefore, if the encrypted information cannot be decrypted, or if the decrypted decryption information does not match the predetermined unique information and verification value format, the device that sent the authentication request including the encrypted information , It can be determined that the device is not a legitimate authenticated device 1.

The authentication unit 24 determines whether or not the authenticated device 1 is valid by using a plurality of authentication requests received within the authentication period, including the encrypted information that can be decrypted by the decryption key. When the decryption key is a common key encryption key, among a plurality of authentication requests received during the authentication period, a plurality of authentication requests including encryption information that can be decrypted using one common key encryption key. Will be used to authenticate the device to be authenticated 1. As described above, when the key of the common key encryption is different for each authenticated device 1, a plurality of authentication requests including the encryption information that can be decrypted by using the key of one common key encryption can be obtained by one authenticated device. It can be considered that it was transmitted from 1, and by performing authentication using the plurality of authentication requests, it is possible to authenticate the authenticated device 1. On the other hand, when the decryption key is a private key, among the plurality of authentication requests received during the authentication period, a plurality of authentication requests including the encryption information that can be decrypted using the private key of the authentication device 2 are used. Then, the authenticated device 1 is authenticated. Here, when the decryption key is a private key, the plurality of authentication requests including the encryption information that can be decrypted using the private key include the authentication requests transmitted from the plurality of authenticated devices 1. There can be. Therefore, for example, when the authentication request includes the ID of the authenticated device 1 that is the source of the authentication request, the authentication unit 24 makes a plurality of authentication requests including the same ID received within the authentication period. It may be used to determine whether the authenticated device 1 is legitimate. It should be noted that determining whether or not the authenticated device 1 is valid by using a plurality of authentication requests may mean using a plurality of authentication requests themselves, or using information related to the plurality of authentication requests. You may. The information related to the plurality of authentication requests may be, for example, a plurality of decryption information acquired from each of the plurality of authentication requests, a reception interval of the plurality of authentication requests, and the number of the plurality of authentication requests. It may be other information related to a plurality of authentication requests. Further, when the authentication request includes the ID of the authenticated device 1 that is the source of the authentication request, the authentication request that has the encryption information that can be decrypted by one common key cryptographic key is usually included in the authentication request. The same ID will be included. Therefore, when the encryption key is a symmetric key cryptographic key, the authentication unit 24 uses a plurality of authentication requests including the same ID received within the authentication period to determine whether the authenticated device 1 is valid or not. You may judge. After receiving the first authentication request from a certain authenticated device 1, the authentication unit 24 uses a plurality of authentication requests received from the authenticated device 1 within a predetermined authentication period to receive the authentication. The authentication device 1 may be authenticated.

The authentication unit 24 determines that the authenticated device 1 is not valid when, for example, all of the plurality of authentication requests received during a certain authentication period are transmitted from the invalid authenticated device 1. .. Further, for example, even if a plurality of authentication requests received during a certain authentication period include an authentication request transmitted from an invalid device, the authentication unit 24 transmits the plurality of authentication requests to the authenticated device. Judge that 1 is not valid. That is, even when a plurality of authentication requests are transmitted from a legitimate authenticated device 1 and an unauthorized authenticated device 1, the authenticated device 1 that is the source of the plurality of authentication requests is not valid. Will be judged. In this case, the source of the authentication request includes at least the attacker's device, and even if the legitimate authenticated device 1 is included in the source, it is not possible to distinguish between the two. Both will be judged to be unjustified.

Further, after the authentication, the authentication unit 24 transmits the verification data including the authentication content and the verification value through the line communication unit 26 via the system server 3. It should be noted that instead of after the certification, it may be after the certification period has expired. Further, the verification value alone may be used without including the authentication content in the verification data.

The line communication unit 26 may be used for communicating with the system server 3 or may be used for other purposes. In the communication with the system server 3, information necessary for maintaining the system such as transmission of verification data described later and ID of the authenticated device 1 and an encryption key may be communicated. It is desirable that the line communication unit 26 and the line communication unit 36 of the system server 3 are constructed with a dedicated line, and the communication means may be, for example, a mobile line network or a wired line network.

Next, the system server 3 according to the present embodiment will be described.
The system server 3 verifies that the authenticated device 1 has been authenticated by the authentication device 2, and is for maintaining and maintaining the system. It may be used for other purposes. The server authentication unit 35 transmits the verification data transmitted from the authentication device 2 via the general circuit communication unit 36 to the authenticated device 1, and uses the verification result verified by the authenticated device 1 to maintain the entire system. To determine. For example, when the possibility of unauthorized use or unauthorized use is received from the authenticated device 1 as a verification result, the encryption key of the authenticated device 1 may be deleted and stopped, or updated and a new one may be issued. can. In addition, verification of unauthorized use can be urged to the system administrator, the user of the authenticated device 1, and the administrator of the authentication device 2. It is desirable that the system server 3 is independent of the authenticated device 1 and the authentication device 2, but it may be installed in the authentication device 2, and the authentication device 2 is the server authentication unit of the system server 3. It may have a function.

[Judgment based on consistency between verification value and verification data]
The authentication unit 24 may determine that the authenticated device 1 is not valid when, for example, a predetermined number or more of duplicates exist in a plurality of decrypted information, and for example, an authentication request is predetermined in a predetermined period. If it is received more than the number of times, it may be determined that the authenticated device 1 is not valid. Further, for example, when the reception interval of the authentication request in the authentication period includes a reception interval whose probability is lower than the threshold value, it may be determined that the authenticated device 1 is not valid, and for example, it is received during the authentication period. When the plurality of decryption information acquired from each of the plurality of authentication requests does not match the unique information, it may be determined that the authenticated device 1 is not valid. Further, the authentication unit 24 may determine whether or not the plurality of decrypted information is consistent with the unique information, for example, with respect to a set of the plurality of decrypted information. For example, when the unique information is a count value, the authentication unit 24 determines that the plurality of decrypted information matches the unique information when the plurality of decrypted information according to the received order meets the count value rule. It may be determined that the plurality of decrypted information is inconsistent with the unique information when it is not determined. Specifically, when a plurality of decryption information is "2", "4", "6", "8" ... In the order of reception, and the unique information generation rule is an increment of two, a plurality of decryption information is provided. Since the decrypted information of the above conforms to the unique information generation rule, the authentication unit 24 determines that the plurality of decrypted information is consistent with the unique information. On the other hand, for example, when a plurality of decrypted information are "2", "4", "6", "6", "8" ... In the order of reception, and the unique information generation rule is incremented by two. Since the plurality of decrypted information does not meet the unique information generation rule, the authentication unit 24 determines that the plurality of decrypted information does not match the unique information. Further, for example, when the unique information is a time, the authentication unit 24 has a time difference which is a difference between the time which is the decryption information and the reception time of the authentication request corresponding to the decryption information for a plurality of decryption information. When the acquired multiple time differences are constant, it is determined that the plurality of decoded information is consistent with the unique information, and when the acquired multiple time differences are not constant, the plurality of decoded information is the unique information. It may be determined that it is inconsistent with. By doing so, even if the clock unit of the authenticated device 1 and the clock unit of the authenticated device 2 are not completely synchronized, it is appropriate whether the decrypted information is consistent with the unique information which is the time. Can be judged. This is because the authenticated device 1 and the authentication device 2 usually perform wireless communication over a short distance, and the delay caused by the wireless communication is considered to be substantially constant for a plurality of authentication requests. The fact that the plurality of time differences are constant may mean that, for example, the difference between the maximum value and the minimum value of the plurality of time differences is smaller than a predetermined threshold value, and the variation of the plurality of time differences. The variance (eg, variance, standard deviation, etc.) may be less than a predetermined threshold. Further, for example, when the unique information is the time, the authentication unit 24 determines that the decryption information corresponding to the authentication request received at the time point A, for example, when the time of the decryption information does not increase according to the order of reception. When the time of time indicates a time point after the time point A, which is the decryption information corresponding to the authentication request received at the time point B, the plurality of decryption information must be consistent with the unique information. You may judge. In that case, it is considered that the authentication request received at time B is a copy and transmission of the authentication request sent before the authentication request received at time A by the attacker's device. be.

When authenticated by the authentication unit 24, the authentication unit 24 transmits the verification data including the authentication content and the verification value to the authenticated device 1 via the line communication unit 26 via the system server 3. For the verification data including the verification value, the verification value included in the authentication request may be selected, one may be randomly selected from the verification values included in the plurality of authentication requests during the authentication period, or a plurality of verification values during the authentication period may be selected. You may choose the verification value included in the first received authentication request. Further, the verification data may be sent a plurality of times after the authentication period or the end of the authentication period, or may be sent only once. The verification data may be transmitted even if the authentication is not performed by the authentication unit 24. The authentication unit 24 may directly transmit to the authenticated device 1 without going through the system server 3.

The authentication unit 24 may determine whether or not the plurality of decryption information matches the verification value, for example, with respect to a set of the plurality of decryption information. For example, the authentication unit 24 determines the time difference, which is the difference between the time when the verification value included in the verification value is generated and the time when the verification value is received, with respect to the time when the verification value included in the plurality of decryption information is generated. When each of the acquired multiple time differences is constant, it is determined that the plurality of decoded information matches the verification value, and when the acquired multiple time differences are not constant, the plurality of decoded information is the verification value. It may be determined that they are inconsistent. By doing so, even if the clock unit of the authenticated device 1 and the clock unit of the authenticated device 2 are not completely synchronized, the decrypted information is matched with the time when the verification value included in the verification value is generated. You can properly judge whether or not you are doing it. This is because the authenticated device 1 and the authentication device 2 usually perform wireless communication over a short distance, and the delay caused by the wireless communication is considered to be substantially constant for a plurality of authentication requests. The fact that the plurality of time differences are constant may mean that, for example, the difference between the maximum value and the minimum value of the plurality of time differences is smaller than a predetermined threshold value, and the variation of the plurality of time differences. The variance (eg, variance, standard deviation, etc.) may be less than a predetermined threshold. Further, for example, when the time at which the verification value included in the verification value is generated does not increase according to the order of reception, for example, the authentication unit 24 generates the verification value included in the verification value received at time point A. Determines that the plurality of decoded information does not match the verification value when indicating a time point after the time point A and the time point in which the verification value included in the verification value received at a certain time point B is generated after the time point A. You may. In that case, it is considered that the verification value received at time B is a verification value transmitted before the verification value received at time A, which is copied and transmitted by the attacker's device. be.

The output unit 25 outputs the determination result by the authentication unit 24. This determination result is information indicating whether the authenticated device 1 is legitimate or not, that is, whether the authenticated device 1 is authenticated or not. It is preferable that the output unit 25 outputs the determination result by the authentication unit 24 to a configuration or device that performs processing according to the authentication result.

The system server 3 transmits the verification data received from the authentication device 2 to the target authenticated device 1 via the line communication unit 26, the line communication unit 36, and the line communication unit 16 in, for example, about 5 minutes. If transmission is not possible, for example, transmission is repeated with a threshold value of about 3 days. If the transmission cannot be performed by the threshold value, it is determined that the authenticated device 1 is not being used, and the system server 3 is notified of the possibility of unauthorized use as a verification result. For example, for safety, a temporary suspension process may be performed.

When the authenticated device 1 receives the verification data, it collates with the data holding the verification value. If they do not match as a result of collation, the system server 3 is notified of unauthorized use as a verification result. For example, for safety reasons, the process of suspension of use may be performed. If they match, you may confirm the user's use. If it is found that the system server is not being used, the system server 3 may be notified of the possibility of unauthorized use as a verification result. When the use is confirmed, the system server 3 may be notified of the legitimate use as a verification result. Since it is necessary to log in to the authenticated device 1 and the target application in order to confirm the judgment result, it is possible to restrict the use when the authenticated device 1 is not in the user's hand. It becomes.

Here, the output of the confirmation of the user's use may be, for example, a display on a display device (for example, a liquid crystal display, an organic EL display, etc.), a transmission to a predetermined device via a communication line, or a printer. It may be printed by the printer, it may be output by a speaker, it may be notified by vibration, it may be stored in a recording medium, or it may be delivered to another component. The output unit 25 may or may not include a device that outputs (for example, a display device, a communication device, a printer, etc.). Further, the output unit 25 may be realized by hardware, or may be realized by software such as a driver that drives those devices.

Next, the operation of the authenticated device 1 will be described with reference to the flowchart of FIG. FIG. 2 is a flowchart showing an authentication request transmission method, which is a process after the authenticated device 1 determines to start transmitting the authentication request. As described above, the authenticated device 1 may determine that, for example, when it receives a predetermined transmission instruction, it starts transmitting the authentication request.

(Step S101) The transmission unit 14 starts the authentication period. The transmission unit 14 may start timing by a timer, for example, in order to detect the end of the authentication period.

(Step S102) The transmission unit 14 determines whether to transmit the authentication request. Then, if the authentication request is transmitted, the process proceeds to step S103, and if not, the process proceeds to step S107. For example, when the authentication request is transmitted at a predetermined time interval, the transmission unit 14 may determine that the authentication request is transmitted at the predetermined time interval.

(Step S103) The acquisition unit 11 acquires unique information. The acquisition of the unique information may be performed, for example, by acquiring the unique portion and combining the acquired unique portion and the non-unique portion.

(Step S104) The verification unit 15 generates a verification value for verification after authentication. The verification value consists of the time when the verification value is generated and a value such as a random number. Further, the generated verification value may be different for each transmission, or may be different for each fixed period such as 1 second.

(Step S105) The encryption unit 13 uses the encryption key to encrypt the unique information acquired in step S103 and the verification value to generate encrypted information.

(Step S106) The transmission unit 14 transmits an authentication request including the encryption information generated in step S105. The authentication request may include information other than the encrypted information. Then, the process returns to step S102.

(Step S107) The transmission unit 14 determines whether or not to end the transmission of the authentication request. Then, when it ends, a series of processes for transmitting the authentication request ends, and if not, the process returns to step S102. The transmission unit 14 may determine that the transmission of the authentication request ends, for example, when the authentication period started in step S101 ends. Specifically, the transmission unit 14 determines that the transmission of the authentication request is terminated when the value of the timer that started the clock in step S101 exceeds the time length of the authentication period, and if not, the transmission unit 14 determines that the transmission of the authentication request is terminated. , You may decide that it will not end.

The flowchart of FIG. 2 shows a case where acquisition of unique information, generation of encrypted information, and transmission of an authentication request are repeated, but this may not be the case. For example, after a plurality of unique information is acquired and a plurality of encrypted information in which the plurality of unique information is encrypted is generated, transmission of an authentication request including each encrypted information may be repeated. In addition, when the encrypted information in which the same unique information is encrypted is included in a plurality of authentication requests, the unique information is not acquired or the encrypted information is not generated, and the same unique information or the same unique information is used. , The same encrypted information may be used repeatedly. Further, the management of the authentication period in steps S101 and S107 may be performed by a component other than the transmission unit 14, for example, the acquisition unit 11. Further, the order of processing in the flowchart of FIG. 2 is an example, and the order of each step may be changed as long as the same result can be obtained.

Next, the operation of the authentication device 2 will be described with reference to the flowchart of FIG. FIG. 3 is a flowchart showing an authentication method which is a process related to authentication of the authenticated device 1 using a plurality of authentication requests by the authentication device 2.

(Step S201) The receiving unit 21 determines whether or not the authentication request has been received. Then, if the authentication request is received, the process proceeds to step S202, and if not, the process proceeds to step S203. When the receiving unit 21 receives the authentication request intermittently, the receiving unit 21 may receive the authentication request only during the receiving period and may not receive the authentication request during the period other than the receiving period. ..

(Step S202) The decryption unit 23 decrypts the encryption information included in the authentication request received in step S201 using the decryption key, and acquires the decryption information. Then, the process returns to step S201. The decoding unit 23 may store the decrypted information in the storage unit 22 in association with the ID of the authenticated device 1 that is the source of the authentication request. Further, the decoding unit 23 may store the decoding information in the storage unit 22 in association with the reception time of the authentication request corresponding to the decoding information. If the encryption information included in the authentication request received in step S201 cannot be decrypted using the decryption key, the decryption unit 23 may return to step S201 without decrypting. Further, in this case, the authentication unit 24 may determine that the authenticated device 1 that is the source of the authentication request containing the encryption information that cannot be decrypted is not valid.

(Step S203) The authentication unit 24 determines whether or not to perform the authentication process. Then, if the authentication process is performed, the process proceeds to step S204, and if not, the process returns to step S201. For example, the authentication unit 24 could decrypt with the common key encryption key when the authentication period elapses after receiving the first authentication request including the encryption information that could be decrypted with the common key encryption key. It may be determined that the authentication process using a plurality of authentication requests including the encrypted information is performed. Further, the authentication unit 24, for example, receives a plurality of authentications transmitted from the authenticated device 1 of the ID when the authentication period elapses after receiving the first authentication request from the authenticated device 1 of the ID. It may be determined that the authentication process using the request is performed.

(Step S204) The authentication unit 24 determines whether or not a predetermined number or more of duplicates exist in the plurality of decryption information acquired from each of the plurality of authentication requests. Then, if there are a predetermined number or more of duplicates in the plurality of decoded information, the process proceeds to step S209, and if not, the process proceeds to step S205.

(Step S205) The authentication unit 24 determines whether or not the number of times the authentication request is received in a predetermined period exceeds the number of times of the predetermined threshold value. Then, if the number of times the authentication request is received exceeds the number of times of the predetermined threshold value, the process proceeds to step S209, and if not, the process proceeds to step S206.

(Step S206) The authentication unit 24 determines whether or not the reception interval of the authentication request in the authentication period includes a reception interval whose probability is lower than the threshold value. Then, if the reception interval of the authentication request includes a reception interval whose probability is lower than the threshold value, the process proceeds to step S209, and if not, the process proceeds to step S207.

(Step S207) The authentication unit 24 determines whether or not the plurality of decryption information corresponding to each of the plurality of authentication requests received during the authentication period is consistent with the unique information. Then, if the plurality of decoded information matches the unique information, the process proceeds to step S208, and if they do not match, the process proceeds to step S209.

The processes from step S204 to step S207 are performed on, for example, a plurality of authentication requests received within the authentication period, including the encrypted information decrypted by the decryption key. That is, the processes from step S204 to step S207 may be performed on, for example, a plurality of authentication requests received from the authenticated device 1 of a certain ID within the authentication period.

(Step S208) The authentication unit 24 determines that the authenticated device 1 that has transmitted a plurality of authentication requests is valid. That is, the authenticated device 1 has been authenticated.

(Step S209) The authentication unit 24 determines that the authenticated device 1 that has transmitted a plurality of authentication requests is not valid. That is, the authenticated device 1 has not been authenticated.

(Step S210) The output unit 25 outputs the determination results of steps S208 and S209.

(Step S211) The authentication unit 24 selects one verification value included in the decryption information.

(Step S212) The authentication unit 24 transmits the verification value together with the authentication content to the system server 3 as verification data. Then, the process returns to step S201. It should be noted that it may be transmitted directly to the authenticated device 1.

Note that the flowchart of FIG. 3 shows a case where each process from step S204 to step S207 is performed in the authentication process, but it is not necessary. Of those processes, one or more processes need not be performed. However, even in that case, it is preferable that the authentication process using a plurality of authentication requests, for example, at least one of the processes from step S204 to step S206 is performed. Further, the order of processing in the flowchart of FIG. 3 is an example, and the order of each step may be changed as long as the same result can be obtained. For example, each process from step S204 to step S207 may be in a different order. Further, steps S211 and S212 may be executed a plurality of times after the authentication period or the end of the authentication period, or may be executed only once. Further, in the flowchart of FIG. 3, the process ends when the power is turned off or an interrupt for the end of the process occurs.

Next, the operation of the system server 3 will be described with reference to the flowchart of FIG. FIG. 4 is a flowchart showing a method of receiving the verification data transmitted to the authentication device 2 and transmitting the verification data to the authenticated device 1.

(Step S301) The server authentication unit 35 determines whether or not the verification data transmitted from the authentication device 2 has been received. Then, when the verification data is received, the process proceeds to step S302, and if not, the process returns to step S301.

(Step S302) The line communication unit 36 transmits the verification data to the corresponding authenticated device 1.

(Step S303) The server authentication unit 35 confirms whether the verification data can be transmitted to the corresponding authenticated device 1. Then, if it is possible, the process returns to step S301, and if not, the process proceeds to step S304.

(Step S304) The server authentication unit 35 determines whether or not the time elapsed from the time when the verification data is transmitted to the corresponding authenticated device 1 is within the threshold value. Then, if it is within the threshold time, the process proceeds to step S302, and if not, the process proceeds to step S305.

(Step S305) The server authentication unit 35 outputs the possibility of unauthorized use as a verification result because the verification data could not be transmitted to the corresponding authenticated device 1. Further, the verification data may be resent to the corresponding authenticated device 1, or the encryption key may be deleted to stop the use in order to prevent unauthorized use.

Note that S301 in the flowchart of FIG. 4 may be executed a plurality of times or may be executed only once when a plurality of verification data are received for the same verification content. Further, the flow of the system server 3 may be executed by the authentication device 2, and the authentication device 2 may directly communicate with the authenticated device 1.

Next, the verification operation of the authenticated device 1 will be described with reference to the flowchart of FIG. FIG. 5 is a flowchart showing a processing method related to verification of the authenticated device 1 using verification data by the system server 3.

(Step S111) The line communication unit 16 determines whether or not the verification data has been received. Then, when the verification data is received, the process proceeds to step S112, and if not, the process returns to step S111.

(Step S112) The verification unit 15 collates the verification value in the verification data with the retained data.

(Step S113) The verification unit 15 determines whether or not the verification value in the verification data matches the retained data. Then, if they match, the process proceeds to step S114, and if not, the process proceeds to step S116.

(Step S114) The verification unit 15 causes the user of the authenticated device 1 to confirm the validity of the authentication content in the verification data. If the validity is confirmed, the process proceeds to step S115, and if not, the process proceeds to step S117.

(Step S115) The line communication unit 16 transmits to the line communication unit 36 that the validity of the use is confirmed as a verification result, and returns to step S111.

(Step S116) The line communication unit 16 transmits to the line communication unit 36 that it is an unauthorized use as a verification result, and returns to step S111.

(Step S117) The line communication unit 16 transmits the possibility of unauthorized use to the line communication unit 36 as a verification result, and returns to step S111.

Next, the operation of the system server 3 will be described with reference to the flowchart of FIG. FIG. 6 is a flowchart showing the operation of the system server 3 based on the verification result from the authenticated device 1.

(Step S311)
The line communication unit 36 determines whether or not the verification result has been received. Then, when the verification result is received, the process proceeds to step S312, and if not, the process returns to step S311.

(Step S312)
The server authentication unit 35 determines whether the verification result is unauthorized use. Then, if it is an unauthorized use, the process proceeds to step S314, and if not, the process proceeds to step S313.

(Step S313)
The server authentication unit 35 determines whether the verification result may be used illegally. Then, if there is a possibility of unauthorized use, the process proceeds to step S314, and if not, the process returns to step S311.

(Step S314) The server authentication unit 35 takes measures to prevent unauthorized use. For example, the encryption key of the authenticated device 1 can be deleted and stopped, or updated and a new one can be issued. In addition, verification of unauthorized use can be urged to the system administrator, the user of the authenticated device 1, and the administrator of the authentication device 2. After that, the process returns to step S311.

(Step S315) The server authentication unit 35 takes measures to prevent unauthorized use, such as suspending a part of the use, in consideration of the possibility of unauthorized use. After that, the process returns to step S311.

Note that the flowchart of FIG. 6 shows a case where each process from step S312 to step S315 is performed in the verification process, but it may not be the case. Of those processes, one or more processes need not be performed. However, even in that case, it is preferable that at least one of the verification processes, for example, step S312 and step S314, or step S313 and step S315, is performed. Further, the order of processing in the flowchart of FIG. 6 is an example, and the order of each step may be changed as long as the same result can be obtained. For example, the processes of step S312 and step S313 may be performed in different orders. Further, steps S314 and S315 may be executed each time, or may be executed for one group of target authenticated devices as a batch process after a certain period of time has elapsed.

Next, the operations of the authenticated device 1 and the authenticated device 2 according to the present embodiment will be described with reference to specific examples. In this specific example, the receiving unit 21 of the authentication device 2 is assumed to receive the authentication request intermittently. That is, the receiving unit 21 receives the authentication request only during the receiving period, and does not receive the authentication request transmitted from the authenticated device 1 during the other period.

Further, in this specific example, it is assumed that the legitimate authenticated device 1 transmits 10 authentication requests during the authentication period. As described above, since the receiving unit 21 performs intermittent reception, the authentication unit 24 receives when the number of authentication requests received from a certain authenticated device 1 during the authentication period exceeds the threshold value “7”. It shall be determined that the authenticated device 1 is not valid.

Further, in this specific example, it is assumed that the unique information is the time. Then, when the difference between the time of the decryption information and the time when the authentication request corresponding to the decryption information is received exceeds a predetermined threshold value, the authentication unit 24 transmits the authentication request. It shall be determined that the authentication device 1 is not valid. In addition, the unique information shall be encrypted by the key of common key cryptography.

Further, in this specific example, a case where different unique information is included in encrypted information is mainly described for each authentication request transmitted, and the same unique information is used for a plurality of authentication requests transmitted during the authentication period. The case where the encrypted information is included will be described later.

A case where the authentication request is transmitted only from the legitimate authenticated device 1 will be described with reference to FIG. 7. As shown in FIG. 7, it is assumed that an authentication request including information obtained by encrypting times t1 to t10, which are unique information, is transmitted from the authenticated device 1 to the authentication device 2 at times t1 to t10.

Specifically, when the transmission unit 14 of the authenticated device 1 receives the transmission instruction including the ID of the authentication device 2 transmitted from the authentication device 2, the time counting by the timer is started (step S101). It is assumed that the time at that time was t1. Further, the authenticated device 1 determines that the transmission instruction has been transmitted from the authentication device 2 by, for example, matching the ID of the authentication device 2 stored in the storage unit 12 with the ID included in the transmission instruction. You may. Further, since it is the transmission of the first authentication request, the transmission unit 14 determines that the authentication request is immediately transmitted without waiting for a time, and acquires the unique information to the acquisition unit 11 by a route (not shown). The instruction is passed (step S102). Upon receiving the instruction, the acquisition unit 11 acquires the unique information at the time t1 at that time and passes it to the encryption unit 13 (step S103). Upon receiving the time t1 which is unique information, the encryption unit 13 acquires the ID of the authenticated device 1 stored in the storage unit 12, and also acquires the transmission instruction or the ID of the authentication device 2 from the storage unit 12. , Time t1, the ID of the authenticated device 1 and the ID of the authenticated device 2 are encrypted using the common key encryption key stored in the storage unit 12 to generate encrypted information, which is then sent to the transmission unit 14. Pass (step S105). Upon receiving the encrypted information, the transmitting unit 14 transmits the authentication request including the encrypted information and the ID of the authenticated device 1 acquired from the storage unit 12 by broadcasting the BLE communication (step S106). By repeating the transmission of such an authentication request, 10 authentication requests are transmitted from the authenticated device 1 to the authentication device 2 by the time t10 (steps S102 to S106). If the value of the timer started at time t1 immediately after the tenth authentication request is transmitted at time t10 exceeds the time length of the authentication period, the process of transmitting the authentication request ends. (Step S107).

Assuming that the receiving unit 21 of the authentication device 2 is performing intermittent reception, as shown in FIG. 7, only the authentication request transmitted at the time t2, t4, t5, t7, t8, t10 is the authentication device 2. Will be received at. Then, when each authentication request is received (step S201), the decryption unit 23 acquires the ID of the authenticated device 1 included in the authentication request, and obtains the key of the common key encryption associated with the ID. Obtained from the storage unit 22. Using the key of the common key encryption thus acquired, the decryption unit 23 decrypts the encryption information included in the received authentication request and acquires the decryption information (step S202). Then, the decoding unit 23 determines whether or not the ID of the authenticated device 1 included in the decryption information matches the ID of the authenticated device 1 included in the authentication request in plain text, and whether the ID of the authentication device 2 included in the decryption information is included. It is determined whether or not the ID matches the ID of the own device. In this case, it is assumed that the IDs match in each case. Then, the decoding unit 23 stores the decryption information in the storage unit 22 in association with the ID of the authenticated device 1 included in the authentication request and the reception time of the authentication request. If any one of the IDs does not match, the decoding unit 23 does not have to store the decoding information in the storage unit 22. Such processing is repeated every time an authentication request is received.

Regarding the decryption information stored in the storage unit 22, the authentication unit 24 has checked whether the period from the oldest reception time to the current time exceeds the time length of the authentication period for each ID of the authenticated device 1. Please judge. Then, when there is an ID in which the period from the oldest reception time to the current time exceeds the time length of the authentication period, the authentication unit 24 authenticates the authenticated device 1 of the ID. It is determined that the process is to be performed, and the authentication process is performed using the plurality of decryption information and the reception time stored in association with the ID (step S203).

Specifically, the authentication unit 24 determines whether or not there is duplication in the decryption information (step S204). In this case, since each decrypted information includes a different time, the decrypted information will not be duplicated. Therefore, the authentication unit 24 determines whether or not the number of receptions exceeds the threshold value (step S205). In this specific example, it is assumed that the threshold value is set to "7" as described above. Then, as shown in FIG. 7, it is determined that the number of receptions "6" does not exceed the threshold value "7".

Next, the authentication unit 24 uses the reception time stored in the storage unit 22 to acquire reception intervals, which are time intervals from the reception of a certain authentication request to the reception of the next authentication request. .. Then, it is determined whether or not the reception interval includes the reception interval stored in the storage unit 22 whose probability is lower than the threshold value (step S206). In this case, it is assumed that the reception interval whose probability is lower than the threshold value is not included. Therefore, the authentication unit 24 determines whether or not the decrypted information matches the unique information (step S207). Here, it is assumed that it is determined whether or not the time, which is a unique part of the decrypted information, matches the reception time. Specifically, as described above, when the difference between the time included in the decryption information and the reception time of the authentication request corresponding to the decryption information is smaller than a predetermined threshold value, the authentication unit 24 determines the difference. It shall be determined that the decrypted information is consistent with the unique information. Then, the authentication unit 24 makes such a determination for each decryption information. In this specific example, it is assumed that all the decrypted information is determined to be consistent with the unique information. Then, the authentication unit 24 determines that the authenticated device 1 that has transmitted the plurality of authentication requests is valid (step S208). Then, the output unit 25 outputs the determination result (step S209). After the series of determinations is completed, the decryption information or the like corresponding to the ID of the authenticated device 1 to be determined, which is stored in the storage unit 22, may be deleted, or the decryption information or the like has been processed. A flag or the like to that effect may be set. In the latter case, the decryption information or the like for which the flag or the like indicating that the processing has been completed shall not be used in the subsequent authentication processing.

As described above, according to the authenticated device 1 and the authentication request transmission method according to the present embodiment, a plurality of authentication requests including encrypted information in which unique information is encrypted can be transmitted to the authentication device 2. Further, for example, when the encryption is performed using the key of the common key encryption, the encryption can be performed at a higher speed. Further, when the unique information includes a random number value, a counter value, a time, etc., there is an advantage that the unique information can be generated with a low load. Further, by using such unique information, the amount of information of the unique information can be reduced, and as a result, the amount of information included in the authentication request can be reduced. Therefore, even a communication standard having a limited payload length, such as BLE communication, can transmit an authentication request. Further, as described above, authentication can be performed without intervention by the user, and the convenience of the user can be improved.

Further, according to the authentication device 2 and the authentication method according to the present embodiment, secure authentication can be realized by a simple process by using a plurality of authentication requests transmitted from the authenticated device 1. In the encrypted information, when the unique information is encrypted using the key of the common key encryption, the process of decrypting the encrypted information can be performed at high speed. If the key of the common key cryptography is not leaked or the type of unique information is not known, the attacker's device sends the authentication request received from the legitimate authenticated device 1 to the authentication device 2. You can only attack by sending. Therefore, for example, there is a probability in the processing of determining whether or not a predetermined number or more of duplicates exist in a plurality of decrypted information, the processing of determining whether the number of receptions in a predetermined period exceeds the threshold value, and the reception interval of an authentication request. An attacker's device is sent to the source of the authentication request by simple processing such as determining whether or not an interval lower than the threshold is included and determining whether or not the decryption information obtained from the authentication request matches the unique information. Will be able to detect if is included. In this way, it becomes possible to respond to an attack by spoofing, and secure authentication can be realized. In addition, since it is determined whether or not the authenticated device 1 is valid by using a plurality of authentication requests, it is possible to detect fraud that cannot be detected by only one authentication request, which is safe. It is possible to improve the sex. Further, even when the authentication device 2 receives the authentication request intermittently as in BLE communication, the above authentication can be appropriately performed. Further, by receiving such an intermittent authentication request, the power consumption in the authentication device 2 can be reduced.

In the present embodiment, the authentication unit 24 is authenticated by a determination regarding duplication of decrypted information, a determination regarding the number of times the authentication request is received, a determination regarding the reception interval of the authentication request, and a determination regarding the consistency between the decrypted information and the unique information. Although the case of determining whether or not the device 1 is legitimate has been described, the authentication unit 24 may determine whether or not the authenticated device 1 is legitimate by at least one of those determinations. ..

Further, the authenticated device 1 and the authentication device 2 according to the above embodiment may be used to complement other authentication methods. For example, when there is a problem in security only by face authentication, face authentication may be used in combination with the authentication in the above embodiment. Conventionally, when there is a problem in security with face recognition alone, authentication using an IC card or the like has been separately used in combination, but authentication according to the above embodiment and face recognition are used in combination. As a result, it is not necessary to use an IC card or the like, which improves user convenience. The authenticated device 1 and the authentication device 2 according to the above embodiment may be used in combination with, for example, biometric authentication other than face authentication or authentication other than biometric authentication.

Further, in the above embodiment, the authenticated device 1 may be, for example, a device held by a user or a device mounted on a mobile body. In the latter case, for example, it becomes possible to authenticate the mobile body. The moving body may be, for example, a traveling vehicle or a flying vehicle.

Further, in the above embodiment, each process or each function may be realized by centralized processing by a single device or a single system, or distributed processing by a plurality of devices or a plurality of systems. It may be realized by.

Further, in the above embodiment, the transfer of information performed between the respective components depends on, for example, one of the components when the two components that transfer the information are physically different. It may be performed by outputting information and accepting information by the other component, or if the two components that pass the information are physically the same, one component. It may be performed by moving from the processing phase corresponding to the above to the processing phase corresponding to the other component.

Further, in the above embodiment, information related to the processing executed by each component, for example, information received, acquired, selected, generated, transmitted, or received by each component. In addition, information such as threshold values, mathematical formulas, and addresses used by each component in processing may be temporarily or for a long period of time in a recording medium (not shown) even if it is not specified in the above description. In addition, each component or a storage unit (not shown) may store information on a recording medium (not shown). Further, the information may be read from the recording medium (not shown) by each component or a reading unit (not shown).

Further, in the above embodiment, when the information used in each component or the like, for example, the information such as the threshold value and the address used in the processing by each component and various setting values may be changed by the user, the above Although not specified in the description, the user may or may not be able to change the information as appropriate. When the information can be changed by the user, the change is realized by, for example, a reception unit (not shown) that receives a change instruction from the user and a change unit (not shown) that changes the information in response to the change instruction. You may. The reception unit (not shown) may accept the change instruction from, for example, an input device, information transmitted via a communication line, or information read from a predetermined recording medium. ..

Further, in the above embodiment, when two or more components included in the authenticated device 1 have a communication device, an input device, or the like, even if the two or more components physically have a single device. Well, or may have separate devices. The same applies to the authentication device 2.

Further, in the above-described embodiment, each component may be configured by dedicated hardware, or a component that can be realized by software may be realized by executing a program. For example, each component can be realized by a program execution unit such as a CPU reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory. At the time of execution, the program execution unit may execute the program while accessing the storage unit or the recording medium. The software that realizes the authenticated device 1 in the above embodiment is the following program. In other words, this program has a step of acquiring unique information on the computer, a step of generating a verification value and verifying whether the authentication was valid after the authentication of the authentication device, and a step of encrypting the unique information and the verification value with an encryption key. The step of generating the encrypted information, the step of repeatedly sending the authentication request including the encrypted information to the authentication device within the authentication period, and the step of saving the generated verification value are executed, and a plurality of unique information is generated. A program in which a plurality of authentication requests including each encrypted encrypted information are transmitted within the authentication period.

The software that realizes the authentication device 2 in the above embodiment is the following program. That is, this program sends an authentication request to the computer, including the encryption information encrypted by the encryption key, sent from the authenticated device, and the encryption information encrypted by the encryption key sent from the authenticated device. Using multiple authentication requests received within the authentication period, including the step of repeatedly receiving the including authentication request within the authentication period, the step of decrypting the encryption information and acquiring the decryption information, and the step of decrypting the decrypted encryption information. The step of determining whether the authenticated device is legitimate and the step of outputting the determination result in the step of determining whether the authenticated device is legitimate are executed, and the legitimate authenticated device has a plurality of unique information. It is a program that sends a plurality of authentication requests including encrypted information each encrypted within the authentication period.

In the above program, in the transmission step of transmitting information, the receiving step of receiving information, the step of outputting information, and the like, processing that is performed only by hardware, for example, a modem or interface card in the transmitting step or receiving step. At least the processing performed by such as is not included.

Further, this program may be executed by being downloaded from a server or the like, and the program recorded on a predetermined recording medium (for example, an optical disk such as a CD-ROM, a magnetic disk, a semiconductor memory, etc.) is read out. May be performed by. Further, this program may be used as a program constituting a program product.

Further, the number of computers that execute this program may be singular or plural. That is, centralized processing may be performed, or distributed processing may be performed.

FIG. 8 is a diagram showing an example of a computer system 900 that executes the above program and realizes the authenticated device 1 and the authentication device 2 according to the above embodiment. The above embodiment can be realized by computer hardware and a computer program executed on the computer hardware.

In FIG. 8, the computer system 900 is connected to the MPU (Micro Processing Unit) 911, a program such as a bootup program, a ROM 912 such as an application program, a system program, and a flash memory for storing data, and the MPU 911. It includes a RAM 913 that temporarily stores instructions of an application program and provides a temporary storage space, a touch panel 914, a wireless communication module 915, and a bus 916 that interconnects MPU 911, ROM 912, and the like. A wired communication module may be provided instead of the wireless communication module 915. Further, instead of the touch panel 914, a display and an input device such as a mouse or a keyboard may be provided.

The program for causing the computer system 900 to execute the functions of the authenticated device 1 and the authentication device 2 according to the above embodiment may be stored in the ROM 912 via the wireless communication module 915. The program is loaded into RAM 913 at run time. The program may be loaded directly from the network.

The program does not necessarily have to include the computer system 900, an operating system (OS) for executing the functions of the authenticated device 1 and the authentication device 2 according to the above embodiment, a third-party program, and the like. The program may contain only parts of instructions that call the appropriate functions or modules in a controlled manner to achieve the desired result. It is well known how the computer system 900 works, and detailed description thereof will be omitted.

Further, it goes without saying that the present invention is not limited to the above embodiments, and various modifications can be made, and these are also included in the scope of the present invention.

As described above, the authentication verification system, the authenticated device, the authentication device, the authentication verification method, the authentication verification program, the computer-readable recording medium, and the recording device according to the present invention are, for example, in a cash register, an automatic ticket gate, or the like. It can be used for authentication in payment and presentation of tickets.

Claims (11)

The device to be certified and the device to be certified
An authentication device that authenticates the authenticated device and
It is an authentication system equipped with
The authenticated device is
A transmission unit that repeatedly transmits an authentication request including encryption information to the authentication device within the authentication period, and an encryption unit that generates the encryption information by encrypting the unique information and the verification value with an encryption key.
The acquisition unit that generates the unique information and
A verification unit that generates the verification value and verifies whether the authentication was valid after the authentication of the authentication device.
A storage unit for storing the generated verification value and
With
The authentication device is
A receiving unit that repeatedly receives an authentication request including encryption information encrypted by an encryption key transmitted from the authenticated device within the authentication period.
A decryption unit that decrypts the encrypted information and acquires the decrypted information,
Using a plurality of authentication requests received within the authentication period, including the decrypted encrypted information, it is determined whether or not the authenticated device is valid, and after the authentication determination, the verification data including the verification value is collected by the authenticated device. With the authentication unit to send to
An output unit that outputs the judgment result by the authentication unit and
Authentication verification system with. The authentication verification system according to claim 1, wherein the verification value includes a time when the verification value is generated and either a random value or a hash function value. The authentication verification system according to claim 1 or 2, wherein the encryption key is a symmetric key cryptographic key. 6. Authentication verification system. The authentication verification system according to claims 1 to 4, and further.
After the authentication of the authentication device, the verification value from the authentication unit is received and transmitted to the verification unit of the authenticated device, and the authenticated device and the authentication are performed in order to receive the authentication result and the verification result. A line communication unit for communicating with the device,
A server authentication unit that controls the behavior of the system according to the authentication and verification results,
Authentication verification system with a system server. The authentication unit compares the verification values included in the plurality of decryption information acquired from the plurality of authentication requests received during the authentication period, and if no consistency is found, the authenticated device is used. The authentication verification system according to any one of claims 1 to 5, wherein the authentication verification system is determined to be invalid. The authentication verification system according to any one of claims 1 to 6, wherein the transmission unit transmits the unique information and the verification value by different means. The authentication device according to any one of claims 1 to 7, wherein the receiving unit intermittently receives an authentication request. The device to be certified and the device to be certified
An authentication device that authenticates the authenticated device and
This is an authentication verification method for verifying the authentication of the device to be authenticated in the authentication system including the above.
A step in which the authenticated device repeatedly transmits an authentication request including encrypted information to the authenticated device within the authentication period.
A step in which the authenticated device generates the encrypted information by encrypting the unique information and the verification value with an encryption key.
The step in which the authenticated device generates the unique information,
A step of generating the verification value by the authenticated device and verifying whether the authentication is valid after the authentication of the authentication device.
The step in which the authenticated device stores the generated verification value, and
A step in which the authentication device repeatedly receives an authentication request including encryption information encrypted by an encryption key transmitted from the authenticated device within an authentication period.
A step in which the authentication device decrypts the encrypted information and acquires the decrypted information.
The authentication device uses a plurality of authentication requests received within the authentication period, including encrypted information that can be decrypted, to determine whether the authenticated device is valid, and verification data including a verification value after the authentication determination. To the authenticated device, and
A step in which the authentication device outputs a determination result by the authentication unit,
Authentication verification method. The device to be certified and the device to be certified
An authentication device that authenticates the authenticated device and
This is an authentication verification program for verifying the authentication of the device to be authenticated in the authentication system provided with the above.
A step in which the authenticated device repeatedly transmits an authentication request including encrypted information to the authenticated device within the authentication period.
A step in which the authenticated device generates the encrypted information by encrypting the unique information and the verification value with an encryption key.
The step in which the authenticated device generates the unique information,
A step of generating the verification value by the authenticated device and verifying whether the authentication is valid after the authentication of the authentication device.
The step in which the authenticated device stores the generated verification value, and
A step in which the authentication device repeatedly receives an authentication request including encryption information encrypted by an encryption key transmitted from the authenticated device within an authentication period.
A step in which the authentication device decrypts the encrypted information and acquires the decrypted information.
The authentication device uses a plurality of authentication requests received within the authentication period, including encrypted information that can be decrypted, to determine whether the authenticated device is valid, and verification data including a verification value after the authentication determination. To the authenticated device, and
A step in which the authentication device outputs a determination result by the authentication unit,
Authentication verification program that causes the system to execute. A computer-readable recording medium or device on which the program according to claim 10 is recorded.

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