WO2023148807A1

WO2023148807A1 - Communication device, communication system, communication method, and program

Info

Publication number: WO2023148807A1
Application number: PCT/JP2022/003794
Authority: WO
Inventors: 正則今川
Original assignee: 三菱電機株式会社
Priority date: 2022-02-01
Filing date: 2022-02-01
Publication date: 2023-08-10
Also published as: JPWO2023148807A1; JP7546796B2

Abstract

A communication system (100) comprises a plurality of communication devices 2 (2A, 2B, 2C …) that are capable of communicating with each other via a network (1), and that each have the same shared key. Each of the communication devices 2, when operating any other of the plurality of communication devices 2, generates a token for which a digital signature is attached to authentication data using a shared key, and transmits the token to the communication device (2) to be operated. Each of the communication devices 2, when operated from any other of the plurality of communication devices (2), verifies the digital signature of the token received from the operating-side communication device (2), using the shared key to thereby perform authentication, and, if the authentication is successful, allows the operating-side communication device (2) to operate the communication device 2.

Description

Communication equipment, communication system, communication method and program

The present disclosure relates to communication equipment, communication systems, communication methods, and programs.

A user may want to monitor and operate a communication device from a web browser on a user terminal via a network such as the Internet or LAN (Local Area Network). In this case, in order to prevent unauthorized access, the user first enters an ID and password on the login screen from the user terminal and transmits them to the communication device, and the communication device performs user authentication using the ID and password. After successful user authentication, the user terminal can operate the communication device by communicating with the communication device using mechanisms such as Web API and WebSocket. When performing this communication, it is necessary to newly perform authentication other than user authentication. In principle, this authentication must be performed each time the user terminal operates the communication device. Therefore, every time the user operates the communication device, the user is required to enter a password for authentication, resulting in poor operability.

In order to prevent such deterioration of operability, the password entered by the user on the login screen is stored in the web browser, cookie, etc., and the password is automatically sent to the communication device each time communication is performed using Web API, WebSocket, etc. A known method is to transmit to the . However, frequent transmission of confidential information such as passwords poses a security problem.

Also, in order to avoid the above problem, a technology is disclosed in which the communication device side issues an authentication token to the user terminal when the user authentication is successful, and the user terminal uses the token to automatically perform authentication. It is For example, in Japanese Unexamined Patent Application Publication No. 2002-100001, when a plurality of facility management apparatuses are monitored and operated from a user terminal, a representative facility management apparatus performs user authentication first. When the user authentication is successful, the representative facility management device generates an authentication code for each facility management device by encrypting the authentication data to which the digital signature is added using the private key of the own device using the public key of each facility management device, Send to user terminal. The user terminal adds the received authentication code and connects to the facility management apparatus by the WebSocket method. The facility management device decrypts the authentication code received from the user terminal with its own private key and verifies the digital signature with the public key of the representative facility management device, thereby performing authentication. If the authentication succeeds, the user terminal becomes capable of monitoring the equipment management device. Note that the "authentication code" described in Patent Document 1 is information for authentication similar to the "token", and there is no substantial difference between the two.

WO2014/068632

There may be cases where there are multiple communication devices to be operated, and the communication devices want to operate the other side spontaneously without going through the user terminal. Similarly, in such a case, authentication is required when communicating between communication devices using Web API, WebSocket, etc., and it is conceivable to use the above-mentioned token. Here, when operating the communication device from the user terminal, the user terminal accesses the communication device having the token issuing function, and the communication device issues an authentication token when the user authentication is successful. Using the received token, it is possible to communicate with the communication device to be operated. On the other hand, in communication between communication devices in which a user terminal does not intervene, it is difficult to perform authentication because communication devices capable of issuing tokens cannot be specified.

The present disclosure has been made in view of the above circumstances, and provides a communication device, a communication system, and a communication method capable of easily performing authentication when one communication device operates another communication device without intervention of a user terminal. and to provide programs.

In order to achieve the above object, the communication device according to the present disclosure is
One communication device among a plurality of communication devices each holding the same shared key and capable of communicating with each other via a network,
When the own device operates an operation target device that is one of the plurality of communication devices, it generates a token obtained by adding a digital signature to the authentication data with the shared key, and uses the token to perform the operation. a token generation processing unit that transmits to the target device;
verifying, by using the shared key, the digital signature of the token received from the operating-side device when the own device is operated by an operating-side device that is one of the plurality of communication devices; a token authentication processing unit that performs authentication by
a web server unit that enables the operation-side device to operate its own device when authentication by the token authentication processing unit is successful;
Prepare.

According to the present disclosure, it is possible to easily perform authentication when one communication device operates another communication device without the intervention of a user terminal.

A diagram showing the configuration of a communication system according to an embodiment of the present disclosure 1 is a block diagram showing the configuration of a communication device according to an embodiment of the present disclosure; FIG. Block diagram showing the configuration of a user terminal according to an embodiment of the present disclosure Flowchart of processing for operating a communication device from a user terminal according to an embodiment of the present disclosure A diagram schematically showing the structure of a token according to an embodiment of the present disclosure Flowchart of processing for operating another communication device from a communication device according to an embodiment of the present disclosure Flowchart of token update processing according to an embodiment of the present disclosure

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The same reference numerals are given to the same or corresponding parts in the drawings.

A communication system according to an embodiment of the present disclosure will be described. The communication system 100 includes, as shown in FIG. 1, a plurality of

communication devices

2A, 2B, 2C, . In the following description, the

communication devices

2A, 2B, 2C, . . . The communication system 100 has a function of connecting the user terminal 3 to the communication device 2 and operating the communication device 2 . Furthermore, the communication system 100 also has a function of voluntarily connecting one communication device 2 to the other communication device 2 and operating the other communication device 2 without using the user terminal 3 . It should be noted that this "operation" means causing the communication device 2 to perform some processing. As a result, the user terminal 3 and the communication device 2 on the operating side can control and monitor the operated communication device 2, obtain information from the operated communication device 2, and the like. In the following description, communication between the communication devices 2 that does not involve the user terminal 3 is also referred to as inter-device communication.

The communication device 2 is a device capable of communicating with the user terminal 3 and other communication devices 2 via the network 1, such as an air conditioning controller. The communication device 2 is not assumed to be operated directly by the user, and is indirectly operated by the user terminal 3 and other communication devices 2 via the network 1 . As shown in FIG. 2, the communication device 2 includes a communication section 21, a storage section 22, and a control section .

The communication unit 21 is an interface for connecting the communication device 2 to the network 1. The communication unit 21 has a reverse proxy function that restricts connections from communication devices other than the communication device 2 that constitute the communication system 100 . This makes it possible to prevent unauthorized access from a third party.

The storage unit 22 is a nonvolatile storage device such as a hard disk drive, flash memory, etc., and stores various information. For example, the storage unit 22 stores system configuration data 221 , user registration information 222 and shared key 223 .

The system configuration data 221 is data for identifying all communication devices 2 in the communication system 100, including the device itself, from the network 1. For example, the system configuration data 221 is data including the IP address, domain name, host name, etc. of each communication device.

The user registration information 222 is data used when performing user authentication, which will be described later. The user registration information 222 includes a list of pairs of user IDs and passwords of users permitted to connect to the communication device 2 . Note that the user registration information 222 is not limited to the user ID and password, and may be data for using other means that can uniquely identify the user, such as data for fingerprint authentication or a digital certificate.

The shared key 223 is used to generate a token with a digital signature added to the authentication data in the token generation process described later. Also, the shared key 223 is used to verify the digital signature added to the token received from the user terminal 3 or the communication device 2 in token authentication processing, which will be described later. All communication devices 2 included in the communication system 100 hold the same shared key 223 . In initial setting processing when the communication system 100 is configured, settings are manually made such that the same shared key 223 is held in the storage units 22 of all the communication devices 2 . Note that if the same shared key 223 is stored in advance in the firmware of each communication device 2, such an initial setting process can be omitted, but in this case, there is a risk that the shared key 223 will be leaked to the outside. be.

Also, when the communication device 2 is operated from the user terminal 3 or another communication device 2, the storage unit 22 stores an authentication token. A token is information obtained by adding a digital signature to authentication data using the shared key 223, and is used to authenticate the communication device 2 on the operating side.

The control unit 23 includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), etc., and the CPU uses the RAM as a workspace and executes a program stored in the ROM, so that the communication device 2 as a whole. The control unit 23 has a user authentication unit 231, a token generation processing unit 232, a token authentication processing unit 233, a web server unit 234, and a token update unit 235 as functional configurations.

The user authentication unit 231 performs user authentication when receiving an operation request from the user terminal 3 . Specifically, the user authentication unit 231 performs user authentication by comparing the user ID, password, etc. included in the user authentication request from the user terminal 3 with the user registration information 222 .

The token generation processing unit 232 adds a digital signature to the authentication data with the shared key 223 when the user authentication unit 231 succeeds in user authentication, or when the other communication device 2 is operated from its own device through inter-device communication. Then, the generated token is transmitted to the user terminal 3 or the communication device 2 to be operated (operated device).

When the token authentication processing unit 233 is operated by the user terminal 3 or another communication device 2 (operating device), the token authentication processing unit 233 uses the shared key stored in the storage unit 22 as the digital signature of the received token. Authentication is performed by verifying using H.223.

The web server unit 234 functions as a web server for the communication device 2. When the token authentication processing unit 233 succeeds in authentication, the web server unit 234 performs processing for enabling the user terminal 3 or the communication device 2 to operate itself. Specifically, the web server unit 234 receives operation commands by connecting to the user terminal 3 or the communication device 2 on the operating side using Web API, WebSocket, or the like. The web server unit 234 then executes the received operation command and responds with the execution result.

The token update unit 235 performs processing for updating the expiration date of the token stored in the storage unit 22 when the expiration date is short.

Returning to FIG. 1, the user terminal 3 is a console terminal that operates each communication device 2 from a web browser. The user terminal 3 includes a communication unit 31, a storage unit 32, a control unit 33, a display unit 34, and an input unit 35, as shown in FIG.

The communication unit 31 is an interface for connecting the user terminal 3 to the network 1.

The storage unit 32 is a non-volatile storage device such as a hard disk drive, flash memory, etc., and stores various information. For example, the storage unit 32 stores an authentication token acquired from the communication device.

The control unit 33 includes a CPU, RAM, ROM, etc., and the CPU controls the entire user terminal 3 by executing a program stored in the ROM using the RAM as a work space.

The display unit 34 is, for example, an LCD (Liquid Crystal Display), and displays various screens under the control of the control unit 33. For example, the display unit 34 displays a login screen for user authentication.

The input unit 35 is, for example, a keyboard, a mouse, etc., receives input from the user, and outputs a signal corresponding to the input to the control unit 33 . For example, the input unit 35 receives input of a user ID and password from a login screen.

Next, the operation of the communication system 100 will be explained. First, processing when operating the communication device 2 from the user terminal 3 will be described using the flowchart of FIG.

First, the user operates the input unit 35 of the user terminal 3 to enter the URL for connecting to the communication device 2 to be operated into the browser. As a result, the control unit 33 acquires the web content for displaying the login screen from the communication device 2, and causes the display unit 34 to display the login screen (step S101).

Subsequently, the user operates the input unit 35 of the user terminal 3 to enter his/her own ID and password on the login screen, and confirms the input. Accordingly, the control unit 33 transmits a user authentication request including the input ID and password to the communication device (step S102).

Upon receiving the user authentication request, the user authentication unit 231 of the communication device 2 performs user authentication (step S103). Specifically, the user authentication unit 231 confirms that the set of ID and password included in the received user authentication request is registered in the user registration information 222 . Although not shown in the flowchart of FIG. 4, if the user authentication fails, the process ends as an error.

After successful user authentication, the token generation processing unit 232 performs processing to generate a token for authentication. That is, first, the token generation processing unit 232 acquires authentication data indicating that user authentication has succeeded (step S104). The authentication data is arbitrary data, and may be a random number that is meaningless information, but in this embodiment, at least the current date and time information and the IP address of the user terminal 3 that is the source of the operation are included in the authentication data. The IP address of the user terminal 3 may be obtained from the IP address of the source of the received user authentication request. Further, instead of the IP address of the user terminal 3, other address information that can identify the user terminal 3 may be included in the authentication data.

Then, the token generation processing unit 232 generates a token by adding a digital signature to the acquired authentication data using the shared key 223 (step S105). Specifically, the token generation processing unit 232 adds, as a digital signature, a MAC value calculated based on the shared key 223 and the authentication data using a hash-based message authentication code (HMAC) algorithm. As a result, a token having the structure shown in FIG. 5 is generated. The hash function used for calculating the MAC value is SHA-2, SHA-3, etc., but all the communication devices 2 included in the communication system 100 must use the same hash function.

Returning to FIG. 4, the token generation processing unit 232 transmits the generated token to the user terminal 3 (step S106).

Subsequently, the control unit 33 of the user terminal 3 adds the received token and tries to connect to the communication device 2 operated by the WebSocket method (step S107). Here, the WebSocket method is a technical standard for two-way communication between a web server and a web client. If the connection is made using the WebSocket method, unlike the HTTP protocol, it is possible to maintain a constant connection.

Specifically, the control unit 33 of the user terminal 3 adds a token as a parameter to the URL for connecting to the communication device 2 to be operated using the WebSocket method, and attempts to connect to the communication device 2 using the URL. Therefore, the token must be data in a format that can be used as a URL. If the token is data in binary format, it must be converted into a format that can be used in a URL using a method such as Base64. It is conceivable that the token is included in the message first transmitted from the user terminal 3 to the communication device 2 when connecting using the WebSocket method. Therefore, it is preferable to include the token in the URL parameter since it greatly affects the communication system 100 as a whole.

When there is a WebSocket connection from the user terminal 3, the token authentication processing unit 233 of the communication device 2 uses the held shared key 223 to authenticate the digital signature of the token included as a parameter in the URL of the connection. is verified (step S108). Specifically, the token authentication processing unit 233 calculates the MAC value based on the authentication data included in the token and the shared key 223 held in the storage unit 22 using the HMAC algorithm. The token authentication processing unit 233 then verifies that the calculated MAC value and the MAC value included in the token match.

As a result of the verification in step S108, if it is determined that the MAC values do not match and the digital signature is not normal (step S109; No), the token authentication processing unit 233 returns an authentication error to the user terminal 3, and is disconnected (step S111). The user terminal 3 notified of the authentication error ends with an error.

On the other hand, if it is determined that the digital signature is normal as a result of the verification in step S108 (step S109; Yes), the token authentication processing unit 233 checks the date and time information contained in the authentication data in the token and the IP address of the connection source. It is determined whether or not the address is normal (step S110). Specifically, the token authentication processing unit 233 determines whether or not the period from the date and time indicated by the date and time information to the present is within the predetermined validity period of the token. By this determination, old authentication data that has been used in the past can be prevented from being illegally reused, and replay attacks can be prevented. The token authentication processing unit 233 also determines whether or not the IP address of the currently connected user terminal 3 is the same as the IP address of the connection source included in the authentication data. By this determination, the intercepted authentication data can be prevented from being illegally used by other terminals, and spoofing attacks can be prevented.

If it is determined that the date and time information or the IP address of the connection source is not normal (step S110; No), the token authentication processing unit 233 returns an authentication error to the user terminal 3 and disconnects the connection (step S111). . The user terminal 3 notified of the authentication error ends with an error.

On the other hand, if it is determined that the date and time information and the IP address of the connection source are normal (step S110; Yes), the token authentication processing unit 233 returns a normal response to the user terminal 3 assuming that the token is correct (step S112). When the user terminal 3 receives the normal response, a permanent connection is established between the user terminal 3 and the web server unit 234 of the communication device 2 by the WebSocket method (step S113). It becomes possible to operate the communication device 2 from the terminal 3 . After that, when the connection by the WebSocket method is terminated, the token used for authentication is deleted from the user terminal 3 .

Next, the processing when the communication device 2A operates the communication device 2B through inter-device communication will be described using the flowchart of FIG. For example, this process is started when the pre-scheduled date and time comes.

First, the token generation processing unit 232 of the communication device 2A on the operating side transmits an IP address acquisition request of its own device to the communication device 2B on the operated side (step S201). It is necessary to include the IP address of the communication device 2A, which is the connection source, in the authentication data of the token generated in the steps described later. Must. For example, when a NAT router is installed between the communication device 2A and the communication device 2B, when the communication device 2A connects to the communication device 2B, the IP address of the communication device 2A as the connection source is rewritten by the NAT router. It reaches the device 2B. Since the communication device 2A cannot obtain this rewritten IP address by itself, it transmits an IP address acquisition request to the communication device 2B.

When receiving the IP address acquisition request, the control unit 23 of the communication device 2B, which is the operated side, sends the IP address of the transmission source of the request, that is, the IP address of the communication device 2A as seen from the communication device 2B to the communication device 2A. A reply is sent (step S202).

Upon receiving the IP address from the communication device 2B, the token generation processing unit 232 of the communication device 2A performs processing for generating a token for authentication. That is, first, the token generation processing unit 232 acquires authentication data (step S203). The authentication data is arbitrary data, and may be a random number that is meaningless information, but in this embodiment, at least the current date and time information and the IP address of the communication device 2A that is the operation source are included in the authentication data. This IP address is the IP address returned from the communication device 2B in step 202, that is, the IP address of the communication device 2A viewed from the communication device 2B. Note that the authentication data may include other address information that can identify the communication device 2A instead of the IP address of the communication device 2A.

Then, the token generation processing unit 232 of the communication device 2A generates a token by adding a digital signature to the acquired authentication data using the shared key 223 (step S204). This token is a token similar to the token generated when operating the communication device 2 from the user terminal 3, and has a digital signature by HMAC.

Subsequently, the web server unit 234 of the communication device 2A adds the generated token and attempts to connect to the communication device 2B operated by the WebSocket method (step S205). Here, as in the case of operating the communication device 2 from the user terminal 3, it is sufficient to try to connect to the communication device 2B using the URL including the token in the parameter.

When the communication device 2A connects with the WebSocket method, the token authentication processing unit 233 of the communication device 2B uses the held shared key 223 to verify the digital signature of the token included in the URL of the connection ( step S206).

When it is determined that the digital signature is not normal as a result of the verification in step S206 (step S207; No), the token authentication processing unit 233 of the communication device 2B returns an authentication error to the communication device 2A and disconnects the connection. (Step S209). The communication device 2A notified of the authentication error terminates due to an error.

On the other hand, if it is determined that the digital signature is normal as a result of the verification in step S206 (step S207; Yes), the token authentication processing unit 233 of the communication device 2B obtains the date and time information included in the authentication data in the token, and It is determined whether or not the IP address of the connection source is normal (step S208). Specifically, the token authentication processing unit 233 determines whether or not the period from the date and time indicated by the date and time information to the present is within the predetermined validity period of the token. By this determination, old authentication data that has been used in the past can be prevented from being illegally reused, and replay attacks can be prevented. Also, the token authentication processing unit 233 determines whether or not the IP address of the currently connected equipment 2A is the same as the IP address of the connection source included in the authentication data. By this determination, the intercepted authentication data can be prevented from being illegally used by other terminals, and spoofing attacks can be prevented.

If it is determined that the date and time information or the IP address of the connection source is not normal (step S208; No), the token authentication processing unit 233 returns an authentication error to the communication device 2A and disconnects the connection (step S209). . The user terminal notified of the authentication error terminates with an error.

On the other hand, if it is determined that the date and time information and the IP address of the connection source are normal (step S208; Yes), the token authentication processing unit 233 determines that the token is correct and returns a normal response to the communication device 2A (step S210). When the communication device 2A receives the normal response, a constant connection is established between the communication device 2A and the communication device 2B using the WebSocket method (step S211). In the following, it becomes possible to operate the communication device 2B from the communication device 2A without requiring authentication. After that, when the connection by the WebSocket method is terminated, the token used for authentication is deleted from the communication device 2B.

Next, we will explain the token update process. Through the above-described processing, the token received from the operating-side communication device 2A is stored in the storage unit 22 of the operated-side communication device 2B. Here, since a constant connection by WebSocket is established between the

communication devices

2A and 2B, even if the connection is within the validity period, the constant connection is maintained for a long time. Then, the expiration date of the token stored in the communication device 2B may expire, and the constant connection may be disconnected. Therefore, in order to prevent such a situation, the operated-side communication device 2B executes a token update process for updating the token by itself. The token update process is executed at predetermined time intervals while the constant connection by WebSocket is maintained. Token update processing will be described with reference to the flowchart of FIG.

First, the token update unit 235 of the communication device 2B determines whether the period from the date and time indicated by the date and time information included in the authentication data of the token stored in the storage unit 22 to the present has passed the valid period of the token. (step S301). If the validity period has not expired (step S301; No), the token update process ends because there is no need to update the token.

On the other hand, if the validity period has passed (step S301; Yes), the token updating unit 235 of the communication device 2B corrects the date and time information contained in the authentication data of the held token to the current date and time information ( step S302). Then, the token update unit 235 calculates the MAC value by HMAC based on the authentication data with corrected date information and the shared key, and updates the digital signature of the token with the calculated MAC value (step S303). With this, the token update process ends. After that, the token updated by the token update process is deleted from the storage unit 22 of the communication device 2B when the constant connection by WebSocket is disconnected.

Thus, in this embodiment, token update processing is periodically executed during constant connection to update the digital signature of expired tokens and reuse them as valid tokens. This allows the constant connection to be maintained. In the token update process described above, when the expiration date has expired (step S301; Yes), the token is updated (steps S302 and S303). becomes shorter, steps S302 and S303 may be executed. Alternatively, steps S302 and S303 may be uniformly executed to update the token without checking the expiration date. By doing so, the token is updated to the latest date and time each time the token update process is executed, but the token is updated each time, which increases the load on the communication device 2B.

As described above, according to the communication system 100 according to the present embodiment, all the communication devices 2 forming the communication system 100 hold the same shared key 223 . Each communication device 2 has a function of generating an authentication token by itself using the shared key 223 when operating another communication device 2 . Each communication device 2 also has a function of performing authentication by verifying the digital signature of the received token using the shared key 223 when operated by another communication device 2 . That is, all the communication devices 2 have a token issuing function and an authentication function. Therefore, when a token is used for authentication when a communication device 2 operates another communication device 2 in device-to-device authentication, the conventional problem that it is difficult to specify the communication device 2 to which the token can be issued is solved. can be resolved. Therefore, it becomes easy to use the token for authentication when one communication device 2 operates the other communication device 2 without the intervention of the user terminal 3, and the authentication can be easily performed. .

(Modification)
It should be noted that the present disclosure is not limited to the above embodiments, and various modifications are of course possible without departing from the gist of the present disclosure.

In the above-described embodiment, the operation-side user terminal 3 or communication device 2 is connected to the operated-side communication device 2 by WebSocket at all times to perform operations. However, the connection method is not limited to WebSocket. do not have. For example, the user terminal 3 or the communication device 2 on the operating side may connect to the communication device 2 on the operated side via the Web API to perform the operation. In the case of the Web API, unlike WebSockets, there is no constant connection, so authentication using a token is required each time a command is sent or received after connecting via the Web API.

In the above embodiment, the HMAC algorithm is used as the digital signature using the shared key 223, but the digital signature method is not limited to this. For example, a message code authentication algorithm other than HMAC may be used to add a digital signature to the authentication data using the shared key 223 .

In the above embodiment, the authentication data of the token includes the date and time information and the IP address of the connection source, but it is not necessary to include them. For example, the authentication data may be random numbers.

The "token" described in this embodiment may be described as "ticket", "authentication code", etc. in other documents, but these are substantially the same information. This disclosure does not interpret "tokens" narrowly.

Further, in the above embodiment, by applying the program executed by the control unit 23 of the communication device 2 to an existing computer, it is possible to cause the computer to function as the control unit 23 according to the present disclosure.

Any method of distributing such a program can be used. For example, computer-readable recording media such as CD-ROM (Compact Disk Read-Only Memory), DVD (Digital Versatile Disk), MO (Magneto Optical Disk), memory card, etc. may be stored and distributed in , or may be distributed via a communication network such as the Internet.

Various embodiments and modifications of the present disclosure are possible without departing from the broad spirit and scope of the present disclosure. Moreover, the embodiments described above are for explaining the present disclosure, and do not limit the scope of the present disclosure. In other words, the scope of the present disclosure is indicated by the claims rather than the embodiments. Various modifications made within the scope of the claims and within the scope of equivalent disclosure are considered to be within the scope of the present disclosure.

100 communication system 1 network 2 (2A, 2B, 2C) communication device 21 communication unit 22 storage unit 221 system configuration data 222 user registration information 223 shared key 23 control unit 231 user authentication unit 232 Token generation processing unit, 233 token authentication processing unit, 234 web server unit, 235 token update unit, 3 user terminal, 31 communication unit, 32 storage unit, 33 control unit, 34 display unit, 35 input unit

Claims

One communication device among a plurality of communication devices each holding the same shared key and capable of communicating with each other via a network,
When the own device operates an operation target device that is one of the plurality of communication devices, it generates a token obtained by adding a digital signature to the authentication data with the shared key, and uses the token to perform the operation. a token generation processing unit that transmits to the target device;
verifying, using the shared key, the digital signature of the token received from the operating device when the device itself is operated by an operating device that is one of the plurality of communication devices; a token authentication processing unit that performs authentication by
a web server unit that enables the operation-side device to operate its own device when authentication by the token authentication processing unit is successful;
communication equipment.
The token generation processing unit uses a hash-based message authentication code algorithm to generate the token to which a MAC value calculated based on the authentication data and the shared key is added as a digital signature.
A communication device according to claim 1.
The token generation processing unit transmits the token to the operation target device by adding the token to a parameter of a URL for connecting to the operation target device.
A communication device according to claim 1 or 2.
The token generation processing unit converts the token into data in a format that can be added as a parameter of the URL.
A communication device according to claim 3.
The token generation processing unit includes date and time information in the authentication data,
The token authentication processing unit performs authentication based on the date and time information,
A communication device according to any one of claims 1 to 4.
The token generation processing unit includes address information of the device itself in the authentication data,
The token authentication processing unit performs authentication based on the address information,
A communication device according to any one of claims 1 to 5.
The token generation processing unit acquires the address information of the device as seen from the operation target device by transmitting a request to acquire the address of the device itself to the operation target device, and converts the acquired address information of the device into the authentication data. include in
A communication device according to any one of claims 1 to 6.
a token updating unit that modifies date and time information included in the authentication data of the token and updates a digital signature attached to the corrected authentication data based on the shared key;
A communication device according to any one of claims 1 to 7.
A communication system having a plurality of communication devices according to any one of claims 1 to 8.
A communication method performed by one communication device among a plurality of communication devices each holding the same shared key and capable of communicating with each other via a network,
When the one communication device operates an operation target device that is one of the plurality of communication devices, a token is generated by adding a digital signature to the authentication data with the shared key, and the token is generated. transmitting to the operation target device;
When the one communication device is operated by an operating device that is one of the plurality of communication devices, the digital signature of the token received from the operating device is verified using the shared key. Authenticate by
When the authentication is successful, the operating device can operate the device itself;
Communication method.
One communication device among a plurality of communication devices each holding the same shared key and capable of communicating with each other via a network,
When the own device operates an operation target device that is one of the plurality of communication devices, it generates a token obtained by adding a digital signature to the authentication data with the shared key, and uses the token to perform the operation. a token generation processing unit that transmits to the target device;
verifying, by using the shared key, the digital signature of the token received from the operating-side device when the own device is operated by an operating-side device that is one of the plurality of communication devices; a token authentication processing unit that performs authentication by
a web server unit that enables the operation-side device to operate its own device when authentication by the token authentication processing unit is successful;
A program that acts as a