CN116962082A

CN116962082A - Node disconnection reconnection method, device, equipment and storage medium

Info

Publication number: CN116962082A
Application number: CN202311207911.7A
Authority: CN
Inventors: 张云宇; 李超
Original assignee: Beijing Huayuan Information Technology Co Ltd
Current assignee: Beijing Huayuan Information Technology Co Ltd
Priority date: 2023-09-19
Filing date: 2023-09-19
Publication date: 2023-10-27
Anticipated expiration: 2043-09-19
Also published as: CN116962082B

Abstract

The embodiment of the disclosure provides a node disconnection reconnection method, a device, equipment and a storage medium, which are applied to the technical field of attack and defense, wherein the method comprises the following steps: if the upper node in the control tree is disconnected with the server, the upper node is used as a head node of the disconnected subtree, and the disconnected subtree is kept alive; and if the upper node is reconnected with the server, connecting with the upper node, and reconnecting the disconnected subtree to the control tree. In this way, it is possible to solve the case where a plurality of nodes are connected, and a part of the subtree is lost because of one disconnected node.

Description

Node disconnection reconnection method, device, equipment and storage medium

Technical Field

The disclosure relates to the technical field of computers, and further relates to the technical field of attack and defense, in particular to a node disconnection reconnection method, a device, equipment and a storage medium.

Background

During the penetration test, penetration test personnel record the attack path executed by the penetration test personnel and arrange the nodes with certain authority into a control tree. They layered the attack path and build control tree branches according to the relevance of the attack technique, making the control tree a kind of visualization tool, helping penetration testers understand and plan the attack path in order to better evaluate the security of the system.

By using a control tree, penetration testers can better organize the attack ideas and ensure that important attack paths are not missed. They can develop attacks based on the control tree structure, go deep into the system, and attempt to gain higher levels of access rights using different security vulnerabilities and techniques.

In the control tree, once a node is disconnected for some reason, its children are also all disconnected, i.e. a part of the subtree is lost due to the disconnection of one node. This loss of some subtrees can lead to incomplete penetration testing and further to incomplete test results.

Disclosure of Invention

In view of this, the present disclosure provides a method, an apparatus, a device, and a storage medium for reconnecting a node.

According to a first aspect of the present disclosure, a node disconnection reconnection method is provided, which is applied to a lower node of a disconnected node. The method comprises the following steps:

if the upper node in the control tree is disconnected with the server, the upper node is used as a head node of the disconnected subtree, and the disconnected subtree is kept alive;

and if the upper node is reconnected with the server, connecting with the upper node, and reconnecting the disconnected subtree to the control tree.

In some implementations of the first aspect, as a head node of the broken subtree, keeping the broken subtree alive includes:

judging whether the node has the capability of reconnecting with an upper node or not;

if the reconnection capability is not provided, the connection port becomes a head node of the disconnection subtree, keeps the disconnection subtree alive and monitors the connection port to wait for connection;

if the reconnection capability is provided, the connection node becomes a head node of the disconnection sub-tree, keeps the disconnection sub-tree alive and actively connects the disconnection node.

In some implementations of the first aspect, if the upper node reconnects with the server, connecting with the upper node includes:

if the connection port does not have the reconnection capability, monitoring the connection port, responding to a connection instruction of the upper node, and completing connection with the upper node;

if the connection capability is provided, the connection command is used for actively connecting the upper node, receiving the response of the upper node and completing connection with the upper node.

In some implementations of the first aspect, re-accessing the broken subtree to the control tree includes:

node data is sent to the upper node so that the upper node forwards reconnection information and the node data to the server step by step; wherein,,

the node data comprises identity information and basic information of the lower node, survival information and basic information of other child nodes in the disconnected subtree.

In some implementations of the first aspect, as a head node of the broken subtree, keeping the broken subtree alive further comprises:

judging whether the node itself has the capability of being connected with a parent node of a superior node;

if the connection capability is not provided, monitoring a connection port, responding to a connection instruction of a parent node of the upper node, and completing connection with the parent node of the upper node;

if the connection capability is provided, the connection command is used for actively connecting the parent node of the upper node, receiving the response of the parent node of the upper node and completing connection with the parent node of the upper node.

According to a second aspect of the present disclosure, there is provided a node disconnection reconnection apparatus applied to a node subordinate to a disconnection node. The device comprises:

the first processing module is used for keeping the disconnected subtree alive as a head node of the disconnected subtree if the upper node in the control tree is disconnected with the server;

and the second processing module is used for connecting with the upper node and re-accessing the disconnected subtree into the control tree if the upper node is re-connected with the server.

According to a third aspect of the present disclosure, an electronic device is provided. The electronic device includes: at least one processor; and a memory communicatively coupled to the at least one processor; the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method as described above.

According to a fourth aspect of the present disclosure, there is provided a non-transitory computer readable storage medium storing computer instructions for causing a computer to perform a method as described above.

In the method, the operation of the disconnected subtree is kept through the lower node of the disconnected node, so that when reconnection is realized, the sub-nodes in the disconnected subtree do not need identity authentication and quickly access the control tree, and meanwhile, the problem that part of the subtree is lost due to one disconnected node under the condition that the multi-stage nodes are connected is solved.

It should be understood that what is described in this summary is not intended to limit the critical or essential features of the embodiments of the disclosure nor to limit the scope of the disclosure. Other features of the present disclosure will become apparent from the following description.

Drawings

The above and other features, advantages and aspects of embodiments of the present disclosure will become more apparent by reference to the following detailed description when taken in conjunction with the accompanying drawings. For a better understanding of the present disclosure, and without limiting the disclosure thereto, the same or similar reference numerals denote the same or similar elements, wherein:

fig. 1 shows a flowchart of a node reconnection method provided by an embodiment of the present disclosure;

FIGS. 2-4 illustrate exemplary schematic diagrams of a node reconnection method provided by embodiments of the present disclosure;

fig. 5 illustrates a block diagram of a node reconnection apparatus according to an embodiment of the disclosure;

fig. 6 illustrates a block diagram of an exemplary electronic device capable of implementing embodiments of the present disclosure.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present disclosure more apparent, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present disclosure, and it is apparent that the described embodiments are some embodiments of the present disclosure, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments in this disclosure without inventive faculty, are intended to be within the scope of this disclosure.

In addition, the term "and/or" herein is merely an association relationship describing an association object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

In view of the problems mentioned in the background art, the present disclosure provides a method, an apparatus, a device and a storage medium for reconnecting a disconnected node, which are applied to a lower node of the disconnected node.

Specifically, if the upper node in the control tree is disconnected with the server, the upper node is used as a head node of the disconnected subtree, and the disconnected subtree is kept alive; and if the upper node is reconnected with the server, connecting with the upper node, and reconnecting the disconnected subtree to the control tree.

In this way, the situation that part of subtrees are lost due to the disconnection of one connection node under the condition that the multistage nodes are connected can be solved, the disconnection subtrees can be quickly accessed into the control tree again, repeated identity authentication on the sub-nodes in the subtrees is not needed, and the workload of a server can be effectively reduced.

The node disconnection reconnection method, device, equipment and storage medium provided by the present disclosure are described in more detail below with reference to the accompanying drawings and specific embodiments.

Fig. 1 shows a flowchart of a node reconnection method provided by an embodiment of the present disclosure; as shown in fig. 1, the node disconnection reconnection method 100 may include the steps of:

and S110, if the upper node in the control tree is disconnected with the server, the upper node is used as a head node of the disconnected subtree, and the disconnected subtree is kept alive.

Specifically, if the upper node in the control tree is disconnected from the server, the lower node judges whether the lower node has the capability of reconnecting with the upper node or not; if the reconnection capability is not provided, the connection port becomes a head node of the disconnection subtree, keeps the disconnection subtree alive and monitors the connection port to wait for connection; if the reconnection capability is provided, the connection node becomes a head node of the disconnection sub-tree, keeps the disconnection sub-tree alive and actively connects the disconnection node.

According to the embodiment of the disclosure, the lower node maintains the survival of other child nodes in the disconnected subtree, so that the lower node can quickly re-access the disconnected subtree into the control tree when being re-connected with the upper node.

And S120, if the upper node is reconnected with the server, the upper node is connected with the upper node, and the disconnected subtree is reconnected to the control tree.

Specifically, if the connection port does not have the reconnection capability, monitoring the connection port, responding to a connection instruction of the upper node, and completing connection with the upper node; if the connection capability is provided, the connection command is used for actively connecting the upper node, receiving the response of the upper node and completing connection with the upper node.

Further, node data is sent to the upper node so that the upper node forwards reconnection information and the node data to the server step by step; the node data comprises identity information and basic information of a lower node, survival information and basic information of other child nodes in the disconnected subtree.

Specifically, when/after reconnecting, the lower node sends node data to the upper node to inform the upper node that the upper node is a reconnection node, is not a new node, does not need to apply for a new ID to the server, and forwards reconnection information and node data to the server step by step after the upper node receives the node data.

In some embodiments, as a head node of the broken subtree, keeping the broken subtree alive further comprises:

The node disconnection reconnection method 100 provided by the present disclosure is described in more detail below with reference to fig. 2-4 in one embodiment.

Fig. 2 to fig. 4 are schematic diagrams illustrating a node reconnection method according to an embodiment of the present disclosure.

For the existing control tree, each layer of nodes is connected with the node at the upper level through the network level. As shown in FIG. 2, agent0 links agent1, agent1 links agent2 and agent4, agent2 links agent3, and agent3 links agent6.

As shown in fig. 2, agent1 is somehow disconnected (i.e., disconnected from agent0, agent 2); at this time, both of the agent0 and the agent2 connected thereto find that the connection with the agent1 is broken.

agent0, as an upper node, notifies that admin is disconnected from agent1, clears all node records of agent1 and the disconnected subtree after admin receives the message, and stops the interaction service.

agent2 serves as a lower node of agent1, keeps the original state to continue operation after detecting that the connection with the upper node is disconnected, and notifies sub-nodes agent3 and agent4 of a discontinuous connection with admin; accordingly, agent3 and agent4, after receiving the message, forcedly exit the interactive service between themselves and admin, and notify the message of discontinuous connection with admin to the respective child nodes.

As shown in fig. 2, in this state, the connection between agent2, agent3, agent4, and agent6 is not broken, but the control of each node is continued by agent2 as the head node (i.e., root node).

When agent2 finds that agent1 breaks, it determines whether or not it has the ability to reconnect to agent 1.

If it is determined that the agent2 does not have the reconnection capability, the agent2 establishes a link with the agent1 through a passive connection mode (i.e. the agent2 monitors a port and the agent1 actively connects), the agent2 continues to monitor the original connection port to wait for the connection of the agent 1.

If it is determined that the agent2 has reconnection capability, the agent2 can actively establish a connection with the agent1 (i.e. the agent1 listens for a port, and the agent2 actively disconnects the connection established by the port), the agent2 will keep continuously trying to connect to the port that the agent1 listens for every 5 seconds.

The above is the corresponding processing work after the node in the control tree is disconnected, namely the superior node of the disconnected node notifies admin, the node is disconnected, admin deletes the record of the disconnected node and its child node, stop the interaction service between all and every node; the subordinate node of the disconnected node discovers that the father node is disconnected, immediately enters a to-be-connected state, can be reconnected at any time, and notifies that the communication between the respective descendant node and the admin is disconnected, and stops all interactive services. At this time, although the interactive service is stopped, the broken subtree is in an independently surviving state.

Further, while the disconnected subtrees remain in an independent surviving state, we cannot communicate with them, only let them connect again to admin and its child nodes and we can continue to control them.

Specifically, the procedure of reestablishing the connection may be as follows:

if the agent1 is reconnected to the server and reestablishes the connection with the agent0 and the agent2, the agent2 will notify the agent1 first after the agent1 and the agent2 are connected: "agent2 has a UUID (Universally Unique Identifier, universal unique identification code), not a newly added node"; at the same time:

agent2 updates the connection state with agent1 in the cache and notifies agent3 and agent4 that the upstream node has reconnected, and agent3 notifies agent6 that the upstream node has reconnected.

agent2 sends its own basic information, the survival information of child nodes and the basic information of child nodes to agent1, agent1 sends the information of "agent2 (UUID) reconnection", agent3, agent4, the survival information of agent6 and the basic information of agent3, agent4, agent6 to agent0, agent0 forwards the above information to admin, and after admin receives, the connection record of agent2, agent3, agent4, agent6 is saved again, and the basic information of agent2, agent3, agent4, agent6 is updated, thus completing reconnection of an broken subtree with agent2 as the first place.

When agent1 is reconnected to the server, the following differences exist between the different connection states of agent2 and agent1:

as shown in fig. 3, when agent2 passively connects to agent1, agent2 does not have the ability to reconnect to agent1, agent2 listens again to the initially set port, agent1 actively connects to agent2 using a connect command, and sends a handshake packet to agent 2; agent2 responds to the handshake packet from agent1, and agent1 and agent2 reconnect successfully.

agent1 judges that agent2 is a reconnection node, and if a new ID is not required, sends an online message of agent2 to admin, and simultaneously notifies admin: "agent2 is a reconnection node".

after the admin receives the message, node information is saved and the route is refreshed.

agent2 updates the connection state with agent1 and notifies admin: "child node of agent2 is online", and at the same time, child nodes agent3, agent4 are notified: "has reconnected with agent 1".

agent3 and agent4 send their own node information to admin, respectively, and notify admin, respectively: "child node of agent3 online", "child node of agent4 online".

agent3 notifies its child node agent6: "has reconnected to the upstream node"; agent6 sends its own node information to admin, and notifies admin: "child node of agent6 is online".

Repeating the operation until all the nodes are reconnected and node basic information is sent to admin.

As shown in fig. 4, when agent2 actively connects to agent1, agent2 has the ability to reconnect to agent1, agent2 automatically reconnects to the original port every other end, and when agent1 comes online again, it connects to agent1 and sends a handshake packet to agent 1; agent1 responds to the handshake packet from agent2, and agent1 reconnects successfully with agent 2.

It can be understood that the different connection states of the agent2 and the agent1 are mainly different in connection mode when the agent2 is actively/passively connected, and other operations are the same, so detailed operations when the agent2 is actively connected to the agent1 are not repeated here.

In some embodiments, agent1 is disconnected, agent2 is still running, and admin does not perform a node information deletion operation at the first time, but chooses to ignore agent1, so that agent2 directly establishes a connection with agent 0. Similarly, when omitting that the agent1 directly establishes a connection with the agent0, there are two connection states of the agent2 actively connecting the agent0 and the agent2 passively connecting the agent0, and the principles are the same as above, and are not described herein again.

It can be understood that the agent1 is disconnected, the agent2 is still running, and at this time, admin deletes all node information, but the security tester knows the node information of the agent2, so the purpose of omitting disconnected nodes and directly connecting the lower nodes thereof can also be achieved by manually adding the node information.

According to the embodiment of the disclosure, the following technical effects are achieved:

the method solves the problem that when a node is disconnected for a certain reason under the condition that the multistage nodes are connected, the sub-nodes of the node are disconnected, and part of subtrees are lost due to the disconnection of one node, effectively improves the stability of the test environment, and further improves the comprehensiveness of the test result.

The method can quickly re-access the disconnected subtree into the control tree without repeated identity authentication of the sub-nodes in the subtree, thereby effectively reducing the workload of the server and further improving the test efficiency.

It should be noted that, for simplicity of description, the foregoing method embodiments are all described as a series of acts, but it should be understood by those skilled in the art that the present disclosure is not limited by the order of acts described, as some steps may be performed in other orders or concurrently in accordance with the present disclosure. Further, those skilled in the art will also appreciate that the embodiments described in the specification are all alternative embodiments, and that the acts and modules referred to are not necessarily required by the present disclosure.

The foregoing is a description of embodiments of the method, and the following further describes embodiments of the present disclosure through examples of apparatus.

Fig. 5 illustrates a block diagram of a node reconnection apparatus according to an embodiment of the present disclosure. As shown in fig. 5, the node reconnection apparatus 500 may include:

the first processing module 510 is configured to, if a superior node in the control tree is disconnected from the server, serve as a head node of the disconnected subtree, and keep the disconnected subtree alive.

And the second processing module 520 is configured to connect with the upper node and re-connect the disconnected subtree to the control tree if the upper node is re-connected with the server.

In some embodiments, the node reconnection apparatus 500 may further include:

the third processing module is used for judging whether the third processing module has the capability of being connected with a parent node of the upper node or not; if the connection capability is not provided, monitoring a connection port, responding to a connection instruction of a parent node of the upper node, and completing connection with the parent node of the upper node; if the connection capability is provided, the connection command is used for actively connecting the parent node of the upper node, receiving the response of the parent node of the upper node and completing connection with the parent node of the upper node.

It can be understood that each module/unit in the node reconnection apparatus 500 shown in fig. 5 has a function of implementing each step in the node reconnection method 100 provided in the embodiment of the disclosure, and can achieve corresponding technical effects, and a specific working process of the described module may refer to a corresponding process in the foregoing method embodiment, which is not repeated herein for convenience and brevity of description.

According to an embodiment of the disclosure, the disclosure further provides an electronic device, a readable storage medium.

As shown in FIG. 6, electronic device 600 is intended to represent various forms of digital computers, such as laptops, desktops, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular telephones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the disclosure described and/or claimed herein.

The electronic device 600 includes a computing unit 601 that can perform various appropriate actions and processes according to a computer program stored in a ROM602 or a computer program loaded from a storage unit 608 into a RAM 603. In the RAM603, various programs and data required for the operation of the electronic device 600 can also be stored. The computing unit 601, ROM602, and RAM603 are connected to each other by a bus 604. An I/O interface 605 is also connected to bus 604.

A number of components in the electronic device 600 are connected to the I/O interface 605, including: an input unit 606 such as a keyboard, mouse, etc.; an output unit 607 such as various types of displays, speakers, and the like; a storage unit 608, such as a magnetic disk, optical disk, or the like; and a communication unit 609 such as a network card, modem, wireless communication transceiver, etc. The communication unit 609 allows the electronic device 600 to exchange information/data with other devices through a computer network, such as the internet, and/or various telecommunication networks.

The computing unit 601 may be a variety of general and/or special purpose processing components having processing and computing capabilities. Some examples of computing unit 601 include, but are not limited to, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), various specialized Artificial Intelligence (AI) computing chips, various computing units running machine learning model algorithms, a Digital Signal Processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 601 performs the various methods and processes described above, such as method 100. For example, in some embodiments, the method 100 may be implemented as a computer software program tangibly embodied on a machine-readable medium, such as the storage unit 608. In some embodiments, part or all of the computer program may be loaded and/or installed onto the electronic device 600 via the ROM602 and/or the communication unit 609. One or more of the steps of the method 100 described above may be performed when a computer program is loaded into the RAM603 and executed by the computing unit 601. Alternatively, in other embodiments, the computing unit 601 may be configured to perform the method 100 by any other suitable means (e.g., by means of firmware).

Various implementations of the systems and techniques described here above may be implemented in digital electronic circuitry, integrated circuit systems, field Programmable Gate Arrays (FPGAs), application Specific Integrated Circuits (ASICs), application Specific Standard Products (ASSPs), systems-on-chips (SOCs), load programmable mechanism devices (CPLDs), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include: implemented in one or more computer programs, the one or more computer programs may be executed and/or interpreted on a programmable system including at least one programmable processor, which may be a special purpose or general-purpose programmable processor, that may receive data and instructions from, and transmit data and instructions to, a storage system, at least one input device, and at least one output device.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program code may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus such that the program code, when executed by the processor or controller, causes the functions/operations specified in the flowchart and/or block diagram to be implemented. The program code may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of this disclosure, a machine-readable medium may be a tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

To provide for interaction with a user, the systems and techniques described here can be implemented on a computer having: display means for displaying information to a user; and a keyboard and pointing device (e.g., a mouse or trackball) by which a user can provide input to the computer. Other kinds of devices may also be used to provide for interaction with a user; for example, feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form, including acoustic input, speech input, or tactile input.

The systems and techniques described here can be implemented in a computing system that includes a background component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front-end component (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such background, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local Area Networks (LANs), wide Area Networks (WANs), and the internet.

The computer system may include a client and a server. The client and server are typically remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. The server may be a cloud server, a server of a distributed system, or a server incorporating a blockchain.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps recited in the present disclosure may be performed in parallel, sequentially, or in a different order, provided that the desired results of the disclosed aspects are achieved, and are not limited herein.

The above detailed description should not be taken as limiting the scope of the present disclosure. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present disclosure are intended to be included within the scope of the present disclosure.

Claims

1. A node disconnection reconnection method applied to a subordinate node of a disconnection node, the method comprising:

if the upper node in the control tree is disconnected with the server, the upper node is used as a head node of a disconnected subtree, and the disconnected subtree is kept alive;

2. The method of claim 1, wherein the head node that is a broken subtree keeps the broken subtree alive, comprising:

judging whether the node has the capability of reconnecting with the upper node or not;

3. The method of claim 1, wherein the connecting with the upper node if the upper node reconnects with the server comprises:

if the connection port does not have the reconnection capability, monitoring the connection port, responding to the connection instruction of the superior node, and completing connection with the superior node;

and if the connection capability is provided, actively connecting the upper node by using a connect command, receiving the response of the upper node, and completing connection with the upper node.

4. The method of claim 1, wherein the re-accessing the broken subtree to the control tree comprises:

node data is sent to the superior node so that the superior node forwards reconnection information and the node data to the server step by step; wherein,,

the node data comprises the identity information and the basic information of the subordinate node, and the survival information and the basic information of the rest child nodes in the disconnected subtree.

5. The method of claim 1, wherein the head node that is a broken subtree keeps the broken subtree alive, further comprising:

judging whether the parent node of the superior node has the capability of obtaining connection with the parent node of the superior node or not;

if the connection capability is not provided, monitoring a connection port, and responding to a connection instruction of a parent node of the superior node to complete connection with the parent node of the superior node;

6. A node disconnection reconnection apparatus for a subordinate node disconnected from a node, the apparatus comprising:

7. An electronic device, comprising:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein,,

the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method of any one of claims 1-5.

8. A non-transitory computer readable storage medium storing computer instructions for causing the computer to perform the method of any one of claims 1-5.