Anti-quantum collaborative signature method and anti-quantum collaborative signature system

Abstract

The invention provides an anti-quantum collaborative signature method, an anti-quantum collaborative signature system and a method of a server side. The method comprises the following steps: determining a permission client side list, and determining a secret key of the server side according to the permission client side list, anti-quantum parameters sent by a client side and a random number of the server side; receiving a part of signature blocks sent by each client; according to the to-be-signed message, the secret key of the server, the public parameter and the anti-quantum parameter, determining an auxiliary parameter of the server, and according to the auxiliary parameter and a part of signature blocks of each client, generating a collaborative signature; and sending the collaborative signature to the verification client to verify a part of signature blocks of each client, and updating the collaborative signature according to a verification result sent by the verification client, so that the signature authority of the client can be dynamically and accurately controlled, and the anti-quantum security of the collaborative signature is ensured.

Description

Technical Field

[0001] The present application relates to the field of network security technology, and in particular to a quantum-resistant collaborative signature method and a quantum-resistant collaborative signature system. Background Art

[0002] In multi-party collaboration scenarios, collaborative signatures, as a multi-party digital signature mechanism, typically involve multiple signing parties generating partial signatures, ultimately generating a complete and valid signature. Quantum-resistant collaborative signatures can protect against quantum computing attacks, ensuring the security of signature operations in the face of quantum computing threats.

[0003] Currently, quantum-resistant collaborative signatures lack effective, dynamic control over the permissions of participating clients. The leakage or misuse of a signatory's private key directly threatens the security of the entire signature system. This is especially true in quantum-resistant environments, where the cost of replacing signature algorithms is high and key lifecycles are long, making the risk of uncontrolled permissions even more significant.

[0004] Therefore, in the existing technology, quantum-resistant collaborative signatures pose a security risk of failure of the entire signature system when the client private key is leaked or abused. Summary of the Invention

[0005] The purpose of this application is to address the deficiencies in the above-mentioned prior art and provide a quantum-resistant collaborative signature method and a quantum-resistant collaborative signature system, so as to solve the practical problem that the quantum-resistant collaborative signature in the prior art poses a security risk of failure of the entire signature system when the client private key is leaked or abused.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows: In a first aspect, an embodiment of the present application provides a quantum-resistant collaborative signature method, which is applied to a server in a quantum-resistant collaborative signature system; the method includes: Determine an authorized client list, and generate a secret key of the server based on the authorized client list, the quantum resistance parameter sent by the client, and the random number of the server; Receive partial signature blocks sent by each client; Determining auxiliary parameters of the server based on the message to be signed, the server's secret key, public parameters, and the quantum-resistant parameters, and generating a collaborative signature based on the auxiliary parameters and partial signature blocks of each client; The collaborative signature is sent to the verification client to verify the partial signature block of each client, and the collaborative signature is updated according to the verification result sent by the verification client.

[0007] As an optional implementation, generating the server's secret key based on the authorized client list, the quantum-resistant parameter sent by the client, and the random number of the server includes: Determining a target parameter for each client in the authorized client list according to the authorized client list, the quantum resistance parameter, the first random number of the server, and the second random number of the server; The product of the target parameters of each client in the authorized client list is used as the secret key of the server.

[0008] As an optional implementation, determining the server's auxiliary parameters based on the message to be signed, the server's secret key, public parameters, and the quantum-resistant parameters, and generating a collaborative signature based on the auxiliary parameters and a partial signature block of each client includes: Encoding the message to be signed into a first coded random number, and determining a first auxiliary parameter of the server based on the first coded random number, the secret key of the server, and the quantum-resistant parameter; Determining a second auxiliary parameter of the server according to the first encoded random number and the public parameter; Partial signature blocks of each client, the first auxiliary parameter of the server, and the second auxiliary parameter of the server are arranged in random order and combined into the collaborative signature.

[0009] As an optional implementation manner, updating the collaborative signature according to the verification result sent by the verification client includes: Traverse each result in the verification result, and for the current result traversed, if the partial signature block corresponding to the current result is invalid, delete the partial signature block corresponding to the current result from the collaborative signature.

[0010] In a second aspect, an embodiment of the present application provides a quantum-resistant collaborative signature method, which is applied to a client in a quantum-resistant collaborative signature system; the method includes: Generate the client's private key and public key string based on the public parameters sent by the server; Generate a partial signature block of the client based on the message to be signed and the private key and public key string of the client, and send the partial signature result of the client to the server; Receive the collaborative signature sent by the server, and obtain the partial signature block of each client and the auxiliary parameters of the server according to the collaborative signature; Based on the partial signature blocks of each client, the auxiliary parameters of the server, the authorized client list, the random number of the server and the public key string of each client, the partial signature blocks of each client in the collaborative signature are verified in turn to see whether they are valid, and the verification results are obtained and sent to the server.

[0011] As an optional implementation, generating the private key and public key string of the client according to the public parameters sent by the server includes: Generate a private key and a public key string of the client according to the public parameters and the random number of the client.

[0012] As an optional implementation, generating the private key and public key string of the client according to the public parameter and the random number of each client includes: A quantum homomorphic encryption algorithm is used to determine a quantum-resistant random number, where the quantum-resistant random number is the sum of the first random numbers of each client; Generate a private key of the client according to the public parameter, the second random number of the client, and the quantum-resistant random number; Generate a public key string of the client according to the public parameter, the second random number of the client, and the third random number of the client.

[0013] As an optional implementation, generating a partial signature block of the client based on the message to be signed and the private key and public key string of the client includes: Encoding the message to be signed into a second encoded random number; Generate a partial signature block of the client according to the second encoded random number, the private key and the public key string of the client.

[0014] As an optional implementation, the verification of the validity of the partial signature blocks of each client in the collaborative signature in sequence based on the partial signature blocks of each client, the auxiliary parameters of the server, the authorized client list, the random number of the server, and the public key string of each client includes: Determine the auxiliary parameters of each client according to the authorized client list, the public key string of each client, the random number of the server, and the first auxiliary parameter of the server; Determine verification parameters based on the authorized client list, the first random number of the server, and the public key string of each client; Based on the partial signature block of each client, the second auxiliary parameter of the server, the auxiliary parameter of each client, the random number of the server, the verification parameter and the public key string of each client, the validity of the partial signature block of each client in the collaborative signature is verified in turn.

[0015] In a third aspect, an embodiment of the present application provides a quantum-resistant collaborative signature device corresponding to the quantum-resistant collaborative signature method executed by the server, the quantum-resistant collaborative signature device comprising: A first generation module is configured to determine an authorized client list and generate a secret key of the server based on the authorized client list, the quantum resistance parameter sent by the client, and the random number of the server; A first receiving module is used to receive a partial signature block sent by each client; The first generation module is further configured to determine auxiliary parameters of the server based on the message to be signed, the secret key of the server, the public parameters, and the quantum-resistant parameters, and generate a collaborative signature based on the auxiliary parameters and a partial signature block of each client; The updating module is used to send the collaborative signature to the verification client to verify the partial signature block of each client, and update the collaborative signature according to the verification result sent by the verification client.

[0016] As an optional implementation manner, the first generating module is specifically configured to: Determining a target parameter for each client in the authorized client list according to the authorized client list, the quantum resistance parameter, the first random number of the server, and the second random number of the server; The product of the target parameters of each client in the authorized client list is used as the secret key of the server.

[0017] As an optional implementation, the first generating module is specifically configured to: Encoding the message to be signed into a first coded random number, and determining a first auxiliary parameter of the server based on the first coded random number, the secret key of the server, and the quantum-resistant parameter; Determining a second auxiliary parameter of the server according to the first encoded random number and the public parameter; Partial signature blocks of each client, the first auxiliary parameter of the server, and the second auxiliary parameter of the server are arranged in random order and combined into the collaborative signature.

[0018] As an optional implementation, the update module is specifically configured to: Traverse each result in the verification result, and for the current result traversed, if the partial signature block corresponding to the current result is invalid, delete the partial signature block corresponding to the current result from the collaborative signature.

[0019] In a fourth aspect, an embodiment of the present application provides a quantum-resistant collaborative signature device corresponding to the quantum-resistant collaborative signature method executed by the verification client, the quantum-resistant collaborative signature device comprising: A second generation module is used to generate a private key and a public key string of the client according to the public parameters sent by the server; The second generation module is further configured to generate a partial signature block of the client based on the message to be signed and the private key and public key string of the client, and send the partial signature result of the client to the server; A second receiving module is configured to receive the collaborative signature sent by the server, and obtain a partial signature block of each client and auxiliary parameters of the server according to the collaborative signature; The verification module is used to verify whether the partial signature block of each client in the collaborative signature is valid based on the partial signature block of each client, the auxiliary parameters of the server, the authorized client list, the random number of the server and the public key string of each client, obtain the verification result, and send the verification result to the server.

[0020] As an optional implementation, the second generating module is specifically configured to: Generate a private key and a public key string of the client according to the public parameters and the random number of the client.

[0021] As an optional implementation, the second generating module is specifically configured to: A quantum homomorphic encryption algorithm is used to determine a quantum-resistant random number, where the quantum-resistant random number is the sum of the first random numbers of each client; Generate a private key of the client according to the public parameter, the second random number of the client, and the quantum-resistant random number; Generate a public key string of the client according to the public parameter, the second random number of the client, and the third random number of the client.

[0022] As an optional implementation, the second generating module is specifically configured to: Encoding the message to be signed into a second encoded random number; Generate a partial signature block of the client according to the second encoded random number, the private key and the public key string of the client.

[0023] As an optional implementation, the verification module is specifically configured to: Determine the auxiliary parameters of each client according to the authorized client list, the public key string of each client, the random number of the server, and the first auxiliary parameter of the server; Determine verification parameters based on the authorized client list, the first random number of the server, and the public key string of each client; Based on the partial signature block of each client, the second auxiliary parameter of the server, the auxiliary parameter of each client, the random number of the server, the verification parameter and the public key string of each client, the validity of the partial signature block of each client in the collaborative signature is verified in turn.

[0024] In a fifth aspect, an embodiment of the present application provides an electronic device, which is the server or the verification client. The electronic device includes: a processor, a memory and a bus, the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the memory through the bus, and the processor executes the machine-readable instructions to execute the method steps performed by the server described in the first aspect or the verification client described in the second aspect.

[0025] In a sixth aspect, an embodiment of the present application provides a quantum-resistant collaborative signature system, the quantum-resistant collaborative signature system comprising: a server and a plurality of clients communicatively connected to the server; The server is used to execute the method steps of the first aspect above; The verification client among the multiple clients is used to execute the method steps described in the second aspect above.

[0026] The beneficial effects of this application are: The present application provides a quantum-resistant collaborative signature method and system. The client generates its private key and public key string based on the public parameters sent by the server, and the server receives the quantum-resistant parameters sent by the client. The server determines the authorized client list and generates the server's secret key based on the authorized client list, the quantum-resistant parameters, and the server's random number. The client generates the client's partial signature block based on the message to be signed and the client's private key and public key string. The server receives the partial signature block of each client, determines the server's auxiliary parameters based on the message to be signed, the server's secret key, the public parameters, and the quantum-resistant parameters, and generates a collaborative signature based on the auxiliary parameters and the partial signature block of each client, and sends the collaborative signature to the verification client. The verification client extracts the partial signature block of each client and the server's auxiliary parameters from the collaborative signature, and verifies the validity of the partial signature block of each client in the collaborative signature based on the partial signature block of each client, the server's auxiliary parameters, the authorized client list, the server's random number, and the public key string of each client, obtains a verification result, and sends the verification result to the server. The server dynamically updates the collaborative signature based on the verification results, deleting invalid signature blocks from the collaborative signature and retaining only the valid signature blocks of the permission-controlled clients in the permission-controlled list, ultimately obtaining the updated collaborative signature. Because the updated collaborative signature is a valid collaborative signature composed of all permission-controlled clients with legitimate signing authority, it avoids the security risk of the entire signature system being invalidated due to the leakage or misuse of a single client's private key, enabling dynamic and precise control of client signing authority and ensuring the quantum security of the collaborative signature. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A schematic diagram of the architecture of the quantum-resistant collaborative signature system provided in an embodiment of the present application; Figure 2 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 1 ; Figure 3 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 2 ; Figure 4 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 3 ; Figure 5 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 4 ; Figure 6 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 5 ; Figure 7 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 6 ; Figure 8 A module structure diagram of a quantum-resistant collaborative signature device provided in an embodiment of the present application; Figure 9 A module structure diagram of another quantum-resistant collaborative signature device provided in an embodiment of the present application; Figure 10 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of illustration and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowcharts can be implemented out of sequence, and steps without logical context can be reversed or implemented simultaneously. In addition, those skilled in the art, under the guidance of the contents of this application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0030] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.

[0031] It should be noted that the term "comprising" will be used in the embodiments of the present application to indicate the existence of the features declared thereafter, but does not exclude the addition of other features.

[0032] Currently, quantum-resistant collaborative signatures in multi-party collaborative scenarios lack effective, dynamic control over the permissions of participating clients. The leakage or misuse of a signatory's private key directly threatens the security of the entire signature system. This is especially true in quantum-resistant environments, where signature algorithm replacement costs are high, key lifecycles are long, and the risk of uncontrolled permissions is high. In other words, existing quantum-resistant collaborative signatures pose a security risk of rendering the entire signature system inoperable if a client's private key is leaked or misused.

[0033] Based on the above problems, the embodiments of the present application propose a quantum-resistant collaborative signature method. In the quantum-resistant collaborative signature system, the server dynamically controls the clients with legal signing authority. During the collaborative signature generation process, only the signature blocks generated by the permission-controlled clients are ultimately determined to be legal and participate in the formation of a valid collaborative signature; the signature blocks generated by non-permission-controlled clients are identified and eliminated during the verification phase. This avoids the security risk of the entire signature system failing due to the leakage or abuse of a single client's private key, achieves dynamic and precise control of the client's signing authority, and ensures the quantum-resistant security of the collaborative signature.

[0034] Figure 1 This is a schematic diagram of the architecture of the quantum-resistant collaborative signature system provided in the embodiment of the present application, as shown in FIG. Figure 1 As shown in Figure 1, the quantum-resistant collaborative signature system includes a server and multiple clients communicating with the server. Figure 1 For example, the server and The server dynamically controls the participation of clients with legal signing authority in forming a valid collaborative signature based on the authorized client list, and dynamically updates some signature blocks in the collaborative signature according to the verification structure sent by the verification client to eliminate some signature blocks generated by non-authorized clients.

[0035] Each client generates a partial signature block and sends it to the server to participate in the collaborative signature. The validity of the partial signature blocks generated by each client is verified, and the partial signature blocks generated by each permission-controlled client in the permission client list are judged as valid partial signature blocks, and the partial signature blocks generated by the non-permission-controlled client are judged as invalid partial signature blocks. The verification result of the partial signature block of each client is sent to the server. Any client among the clients.

[0036] Based on this, a permission control mechanism is introduced in the collaborative signing process to avoid the security risk of the entire signature system failing due to the leakage or abuse of a single client's private key.

[0037] Figure 2 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 1 , taking the interaction between the server and the verification client in the quantum-resistant collaborative signature system as an example, the process of the quantum-resistant collaborative signature method is explained. Among them, the verification client is Any client among the clients. Figure 2 As shown, the method includes: S101. The server sends common parameters to each client.

[0038] Optionally, the server defines two large prime numbers Multiplicative group of order and , define the bilinear map , and select two hash functions to map binary strings of arbitrary length to groups and model The residual class ring , that is, mapped to a range of 0 to The server will select an integer from the remaining classes. Randomly select 、 、 Three random numbers. Among them, For characterization The version number of the client.

[0039] The server side depends on the number of clients And the random number on the server and ,calculate public parameters, and The public parameters are sent to clients. Among them, The common parameters include: .in, , , ,…, .

[0040] It is worth mentioning that is a generator, which is a group A special element in the group All elements in can be expressed as generators The power form of .

[0041] S102: The client generates a private key and a public key string of the client according to the public parameters.

[0042] Optionally, The client receives the public parameters and generate The private key and public key string of each client. Any one of the clients , generate the client The private key and public key string of the client. The private key includes and , client The public key string is .

[0043] Client Public key string A public key in , where The public keys in the public key strings published by the two clients are different.

[0044] S103. The server receives the quantum-resistant parameters sent by the client.

[0045] Optionally, the client Calculating quantum-resistant parameters , and the quantum-resistant parameter Send to the server, the server receives the client The quantum-resistant parameters sent.

[0046] Among them, the quantum resistance parameter , for The unified quantum-resistant random number generated by the joint decryption of the clients, Used to implement The client is resistant to quantum attacks, ensuring Quantum-resistant security for each client.

[0047] S104. The server determines the authorized client list and generates the server's secret key based on the authorized client list, the quantum-resistant parameters sent by the client, and the random number of the server.

[0048] Optionally, the server determines the authorized client list based on the client authority control information pre-entered by the user. For example, if the client authority control information indicates The clients with controlled permissions are client 1, client 3, client 4, and client 5. The server determines the list of authorized clients. .

[0049] The server side lists the authorized clients , quantum-resistant parameters And the random number on the server side, generate the server's secret key .

[0050] S105. The client generates a partial signature block of the client according to the message to be signed and the private key and public key string of the client.

[0051] Optionally, The clients each respond according to the message to be signed And the client's private key and public key string, generate A partial signature block of each client.

[0052] for Any one of the clients , client According to the message to be signed , Client Private key and and the client Public key string , generate the client Partial signature block .

[0053] S106. The server receives the partial signature blocks sent by each client.

[0054] Optionally, for Any one of the clients , client The client Partial signature block Sent to the server. That is, the server receives Sent by the client Partial signature blocks, including 、 、…、 .

[0055] S107. The server determines the server's auxiliary parameters based on the message to be signed, the server's secret key, public parameters, and quantum-resistant parameters, and generates a collaborative signature based on the auxiliary parameters and partial signature blocks of each client.

[0056] Optionally, the server can , the server's secret key , public parameters, quantum-resistant parameters , determine the auxiliary parameters of the server , including the first auxiliary parameter of the server and the second auxiliary parameter .

[0057] Server combination Client A partial signature block, together with the first auxiliary parameter of the server and the second auxiliary parameter , generate collaborative signature That is, collaborative signature .

[0058] S108: Verify that the client receives the collaborative signature sent by the server.

[0059] Optionally, the server will generate a collaborative signature Send to Any client among the clients receives the collaborative signature at this time The client acts as the authentication client.

[0060] For example, the server generates the collaborative signature Send to client , client Acting as a verification client to receive the collaborative signature from the server .

[0061] S109: The verification client obtains a partial signature block of each client and auxiliary parameters of the server according to the collaborative signature.

[0062] Optionally, verify that the client is signing from the collaboration Get the partial signature block of each client from the collaborative signature Extracted from Client Partial signature blocks, including 、 、…、 , and from the collaborative signature Extract the auxiliary parameters of the server, including the first auxiliary parameter of the server and the second auxiliary parameter .

[0063] S110. The verification client verifies whether the partial signature blocks of each client in the collaborative signature are valid based on the partial signature blocks of each client, the auxiliary parameters of the server, the authorized client list, the random number of the server, and the public key string of each client, and obtains the verification result.

[0064] Optionally, authenticate the client against Client Partially signed blocks (i.e. 、 、…、 ), auxiliary parameters of the server , Authorization Client List , the random number on the server side, and Client The public key published in each public key string is used to verify whether the partial signature block of each client in the collaborative signature is valid.

[0065] Specifically, the authentication client will authorize the client list The partial signature blocks generated by the permission-controlled clients are judged as valid partial signature blocks, and the partial signature blocks generated by the non-permission-controlled clients are judged as invalid partial signature blocks. The verification result of the partial signature block of each client.

[0066] For example, assuming there are 6 clients in total, the permission client list is , that is, the permission-controlled clients are client 1, client 3, client 4, and client 5, and the non-permission-controlled clients are client 2 and client 6. The verification client will block the partial signature of client 1 、Partial signature block of client 3 , Partial signature block of client 4 and the partial signature block of client 5 The partial signature block is determined to be valid and the partial signature block of client 2 is and the partial signature block of client 6 The partial signature block is judged to be invalid and the verification result is obtained.

[0067] S111. The verification client sends the verification result to the server.

[0068] Optionally, the verification client sends the verification result to the server, so that the server dynamically updates the collaborative signature according to the verification result from the verification client.

[0069] The verification result is used to indicate Client Whether the partial signature block is valid.

[0070] S112. The server updates the collaborative signature based on the verification result.

[0071] Optionally, the server dynamically updates the collaborative signature based on the verification result from the verification client. Specifically, the server dynamically updates the collaborative signature based on the verification result. Client The invalid partial signature blocks in the collaborative signature are dynamically deleted based on whether the partial signature blocks are valid, and only the valid partial signature blocks of the permission-controlled client are retained, and finally the updated collaborative signature is obtained.

[0072] The updated collaborative signature is an effective collaborative signature consisting of various permission-controlled clients with legal signing authority. In various scenarios that require multi-party collaboration and have strict requirements on signature authority, such as identity authentication and data interaction of IoT devices, transaction signature verification in blockchain, and document approval signature in e-government systems, it can accurately control the client's signature authority and ensure quantum security during the collaborative signing process.

[0073] In this embodiment, the client generates its private and public key strings based on the public parameters sent by the server, and the server receives the quantum resistance parameters sent by the client. The server determines the authorized client list and, based on the authorized client list, the quantum resistance parameters, and the server's random number, generates its secret key. The client generates a partial signature block based on the message to be signed and the client's private and public key strings. The server receives each client's partial signature block and determines its auxiliary parameters based on the message to be signed, the server's secret key, the public parameters, and the quantum resistance parameters. Based on the auxiliary parameters and each client's partial signature block, it generates a collaborative signature and sends the collaborative signature to the verification client. The verification client extracts each client's partial signature block and the server's auxiliary parameters from the collaborative signature. Based on each client's partial signature block, the server's auxiliary parameters, the authorized client list, the server's random number, and each client's public key string, it verifies the validity of each client's partial signature block in the collaborative signature, obtains a verification result, and sends the verification result to the server. The server dynamically updates the collaborative signature based on the verification results, deleting invalid signature blocks from the collaborative signature and retaining only the valid signature blocks of the permission-controlled clients in the permission-controlled list, ultimately obtaining the updated collaborative signature. Because the updated collaborative signature is a valid collaborative signature composed of all permission-controlled clients with legitimate signing authority, it avoids the security risk of the entire signature system being invalidated due to the leakage or misuse of a single client's private key, enabling dynamic and precise control of client signing authority and ensuring the quantum security of the collaborative signature.

[0074] Figure 3 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 2 ,like Figure 3 As shown, in the above step S104, the server's secret key is generated according to the authorized client list, the quantum-resistant parameter sent by the client, and the random number of the server, including: S201. Determine a target parameter for each client in the authorized client list according to the authorized client list, the quantum resistance parameter, the first random number of the server, and the second random number of the server.

[0075] Optionally, the server can use the permission client list , quantum-resistant parameters , the first random number on the server and the second random number on the server , determine the authorized client list The target parameters of each permission-controlled client are , where the client Indicates the list of authorized clients Any permission-controlled client.

[0076] S202: The product of the target parameters of each client in the authorized client list is used as the secret key of the server.

[0077] Optionally, the server lists the authorized clients Target parameters of each permission-controlled client Perform product operation and determine the server's secret key based on the following formula :

[0078] in, is the server's secret key, is the permission client list, is the quantum-resistant parameter, and The first random number on the server and the second random number on the server are respectively, is the total number of clients, Indicates the list of authorized clients Any permission-controlled client.

[0079] It is worth noting that when the user triggers the permission update mechanism, the client's permissions change and the permission client list Changed to the updated permission client list , the server's secret key Update based on the following formula, update to :

[0080] in, is the updated secret key of the server, This is the updated permission client list. is the quantum-resistant parameter, and The first random number on the server and the second random number on the server are respectively, is the total number of clients, Indicates the list of authorized clients Any permission-controlled client.

[0081] List of clients controlled by permissions Update the server secret key , ensuring that when generating the final collaborative signature, it can dynamically adapt to the client's permission changes and continuously maintain the security of controllable permissions.

[0082] In this embodiment, the server determines the target parameters for each permission-controlled client in the permission client list based on the permission client list, the quantum-resistance parameter, the server's first random number, and the server's second random number. The server uses the product of the target parameters for each permission-controlled client in the permission client list as its secret key. When a user triggers the permission update mechanism, causing the permission client list to change, the server synchronously updates its secret key based on the updated permission client list. This dynamically adapts to client permission changes and continuously maintains the security of controllable permissions.

[0083] Figure 4 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 3 ,like Figure 4 As shown, in the above step S107, the server's auxiliary parameters are determined based on the message to be signed, the server's secret key, public parameters, and quantum-resistant parameters, and a collaborative signature is generated based on the auxiliary parameters and the partial signature blocks of each client, including: S301: Encode the message to be signed into a first coded random number, and determine a first auxiliary parameter of the server based on the first coded random number, a secret key of the server, and a quantum-resistant parameter.

[0084] Optionally, the server sends the message to be signed Encoded as a residual class ring Specifically, the server will sign the message Encoded as the first encoded random number ,and .

[0085] The server side codes the random number according to the first , the server's secret key and quantum-resistant parameters , determine the first auxiliary parameter of the server based on the following formula :

[0086] in, It is the first auxiliary parameter of the server. is the server's secret key, is the quantum-resistant parameter, is the first encoded random number.

[0087] It is worth noting that when the user triggers the permission update mechanism, the client's permissions change and the permission client list Changed to the updated permission client list , the server's secret key Changed to the server's updated secret key When the first auxiliary parameter of the server is Update to the first auxiliary parameter after the server is updated :

[0088] in, The first auxiliary parameter after the server is updated. is the updated secret key of the server, is the quantum-resistant parameter, is the first encoded random number.

[0089] S302: Determine a second auxiliary parameter of the server according to the first encoded random number and the public parameter.

[0090] Optionally, the server can generate a random number based on the first code And the public parameters , determine the second auxiliary parameter of the server based on the following formula :

[0091] in, It is the second auxiliary parameter of the server. is a public parameter, is the first encoded random number.

[0092] S303: Arrange the partial signature blocks of each client, the first auxiliary parameter of the server, and the second auxiliary parameter of the server in random order to form a collaborative signature.

[0093] Optionally, the server will Client Partial signature block, the first auxiliary parameter of the server and the second auxiliary parameter Scramble, confuse The partial signature block and the order of the two auxiliary parameters on the server are combined to obtain the collaborative signature .

[0094] It is worth noting that for the convenience of description, the above collaborative signature middle The partial signature block and the two auxiliary parameters of the server are arranged in order, and the collaborative signature is actually generated. In the process, Partial signature block 、 、…、 And the first auxiliary parameter of the server and the second auxiliary parameter There is a disorder in between.

[0095] In this embodiment, the server encodes the message to be signed into a first coded random number and determines the server's first auxiliary parameter based on the first coded random number, the server's secret key, and the quantum-resistant parameter. The server's first auxiliary parameter is dynamically updated with the server's secret key. Based on the first coded random number and the public parameter, the server determines the server's second auxiliary parameter. The partial signature blocks of each client, the server's first auxiliary parameter, and the server's second auxiliary parameter are shuffled and combined into a collaborative signature. The server then shuffles the signature blocks and the server's two auxiliary parameters to form a collaborative signature.

[0096] As an optional implementation, updating the collaborative signature according to the verification result in step S112 includes: Traverse each result in the verification result. For the current result traversed, if the partial signature block corresponding to the current result is invalid, delete the partial signature block corresponding to the current result from the collaborative signature.

[0097] Optionally, the verification result includes Client For example, the first result is used to indicate whether the partial signature block of client 1 is valid. The result is used to indicate to the client Whether the partial signature block is valid.

[0098] The server traverses each result in the verification result. Taking the second result as an example, if the part of the signature block corresponding to the current result is invalid, it means that the client If it is a non-authorized client, the server will Delete the partial signature block corresponding to the second result, that is Deleting a client Partial signature block , and continue to traverse the third result until the traversal is completed. The collaborative signature obtained after the result is the final collaborative signature. At this time, the final collaborative signature only retains the valid partial signature blocks of each permission-controlled client in the permission client list.

[0099] In this embodiment, the server traverses each result in the verification result. For the current result, if the partial signature block corresponding to the current result is invalid, the server deletes the partial signature block corresponding to the current result from the collaborative signature and continues to traverse the next result until all results in the verification result are traversed. The collaborative signature obtained after traversing the last result is used as the final collaborative signature, so that the final collaborative signature retains only the valid partial signature blocks of each permission-controlled client in the authorized client list. This prevents the security risk of the entire signature system being invalidated due to the leakage or abuse of a single client's private key, and realizes dynamic and precise control of client signature permissions.

[0100] As an optional implementation, the step S102 of generating the private key and public key string of the client according to the public parameters includes: Generate the client's private key and public key string based on the public parameters and the client's random number.

[0101] Optionally, for Any one of the clients , client From the remaining ring Randomly select 、 、 Three random numbers.

[0102] Client according to These public parameters and 、 、 These three random numbers generate the client Private key 、 and public key string .

[0103] In this embodiment, the client generates the client's private key and public key string based on the public parameters and the client's random number. By introducing the random number, the uniqueness and unpredictability of each client's key are ensured.

[0104] Figure 5 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 4 ,like Figure 5 As shown, the above steps generate the client's private key and public key string based on the public parameters and the client's random number, including: S401. Use a quantum homomorphic encryption algorithm to determine a quantum-resistant random number, where the quantum-resistant random number is the sum of the first random numbers of each client.

[0105] Optionally, the first random number of each client is transmitted using the Quantum Homomorphic Encryption (QHE) algorithm. Ciphertext The additive form of , decrypt the ciphertext locally on each client and get the sum of the plaintext, recorded as .

[0106] in, For quantum-resistant random numbers, quantum-resistant random numbers The sum of the first random numbers of each client, quantum-resistant random number for A unified random number for each client is used to achieve resistance to quantum attacks.

[0107] S402: Generate a private key of the client based on the public parameters, the second random number of the client, and the quantum-resistant random number.

[0108] Optionally, for Any one of the clients , client According to the public parameters , Client The second random number and quantum-resistant random numbers , based on the following formula to generate the client Private key and :

[0109]

[0110] in, and For the client The private key of is a public parameter, For the client The second random number, For quantum-resistant random numbers, is a generator, which is a group A special element in .

[0111] S403: Generate a public key string of the client according to the public parameters, the second random number of the client, and the third random number of the client.

[0112] Optionally, for Any one of the clients , client According to the public parameters , Client The second random number and client The third random number , generate the client Public key string .

[0113] in, The public key in the public key string published by each client is ,in, .

[0114] In this embodiment, a quantum homomorphic encryption algorithm is used to calculate the sum of each client's first random number to obtain a quantum-resistant random number. The client generates its private key based on the public parameters, the client's second random number, and the quantum-resistant random number. Furthermore, the client generates its public key based on the public parameters, the client's second random number, and the client's third random number. This ensures the uniqueness and unpredictability of each client's key and provides resistance to quantum attacks.

[0115] Figure 6 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 5 ,like Figure 6 As shown, in the above step S105, a partial signature block of the client is generated according to the message to be signed and the private key and public key string of the client, including: S501. Encode the message to be signed into a second encoded random number.

[0116] Optionally, for Any one of the clients , client Message to be signed Encoded as a residual class ring Specifically, the server will sign the message Encoded as the second encoded random number ,and .

[0117] in, The second encoding random number obtained by each client is different. For example, the second encoding random number of client 1 is , client The second encoded random number is , I will not go into details here.

[0118] S502: Generate a partial signature block of the client according to the second encoded random number, the private key and the public key string of the client.

[0119] Optionally, the client According to the second coded random number , Client Private key 、 and public key string , generate the client Partial signature block Specifically, the client Partial signature block ,in, For the client Public key string The public key published in .

[0120] Among them, the client Partial signature block It is represented in the form of an array. Represents the client Partial signature block The first value in , Represents the client Partial signature block The second value in , Represents the client Partial signature block The third value .

[0121] In this embodiment, the client encodes the message to be signed into a second coded random number and generates a partial signature block based on the second coded random number, quantum-resistance parameters, and the client's private and public key strings. Quantum-resistance security is ensured during the generation of the partial signature block.

[0122] Figure 7 Schematic diagram of the process of the quantum-resistant collaborative signature method provided in the embodiment of this application Figure 6 ,like Figure 7 As shown, in the above step S110, based on the partial signature block of each client, the auxiliary parameters of the server, the authorized client list, the random number of the server, and the public key string of each client, the partial signature block of each client in the collaborative signature is verified in turn to determine whether it is valid, and the verification result is obtained, including: S601: Determine the auxiliary parameters of each client according to the authorized client list, the public key string of each client, the random number of the server, and the first auxiliary parameter of the server.

[0123] Optionally, authenticate the client against a list of authorized clients , the public key in each client's public key string, and the first random number of the server and the first auxiliary parameter of the server , based on the following formula to determine the client Auxiliary parameters :

[0124] in, For the client Auxiliary parameters, It is the first auxiliary parameter of the server. is the first random number of the server. is the permission client list, For the client Public key, client Indicates the list of authorized clients Any permission-controlled client.

[0125] S602: Determine verification parameters based on the authorized client list, the first random number of the server, and the public key string of each client.

[0126] Optionally, authenticate the client against a list of authorized clients , the first random number on the server And the public key string of each client, the verification parameters are determined based on the following formula :

[0127] in, To verify the parameters, The first random number of the server, the client Indicates the list of authorized clients Any permission-controlled client.

[0128] Validation Parameters Aggregate the public key information of all permission-controlled clients to form a public verification base.

[0129] S603. Verify in sequence whether the partial signature blocks of each client in the collaborative signature are valid based on the partial signature blocks of each client, the second auxiliary parameters of the server, the auxiliary parameters of each client, the random number of the server, the verification parameters, and the public key string of each client.

[0130] Optionally, the verification client can use the partial signature block of each client to verify the , the second auxiliary parameter of the server , auxiliary parameters of each client , the first random number on the server , the third random number on the server , verification parameters The public key in each client's public key string is used to verify the validity of each client's partial signature block in the collaborative signature based on the following formula:

[0131] in, To verify the parameters, For the client Partial signature block The first value in , For the client Partial signature block The second value in , For the client Partial signature block The third value , It is the second auxiliary parameter of the server. For the client Auxiliary parameters, The first random number of the server. The third random number of the server. For the client Public key.

[0132] Specifically, for the client If both sides of the above equation are equal, that is, the equation is established, then the client For permission-controlled clients, the client Partial signature block Valid. Accordingly, if the left and right sides of the above equation are not equal, that is, the equation does not hold, it means that the client For non-authorized clients, the client Partial signature block Invalid, the server needs to delete the client in the collaborative signature later Partial signature block .

[0133] In this embodiment, the verification client determines the auxiliary parameters of each client based on the authorized client list, the public key string of each client, the random number of the server, and the first auxiliary parameter of the server, and determines the verification parameter based on the authorized client list, the first random number of the server, and the public key string of each client. For each client, the verification client verifies the validity of each client's partial signature block in the collaborative signature based on the partial signature block of each client, the second auxiliary parameter of the server, the auxiliary parameter of each client, the random number of the server, the verification parameter, and the public key string of each client. This implements effective verification of each client's partial signature block so that the server can eliminate invalid partial signature blocks and ensure the validity of each partial signature block in the ultimately generated collaborative signature.

[0134] Based on the same inventive concept, the embodiments of the present application also provide a quantum-resistant collaborative signature device corresponding to the quantum-resistant collaborative signature method executed by the server. Since the principle of solving the problem by the device in the embodiments of the present application is similar to the quantum-resistant collaborative signature method executed by the server in the above-mentioned embodiments of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0135] Figure 8 This is a module structure diagram of a quantum-resistant collaborative signature device provided in an embodiment of the present application, such as Figure 8 As shown, the device includes: The first generation module 801 is used to determine the authorized client list and generate the server's secret key based on the authorized client list, the quantum-resistant parameter sent by the client, and the random number of the server.

[0136] The first receiving module 802 is configured to receive a partial signature block sent by each client.

[0137] The first generation module 801 is further configured to determine auxiliary parameters of the server based on the message to be signed, the server's secret key, public parameters, and quantum-resistant parameters, and to generate a collaborative signature based on the auxiliary parameters and partial signature blocks of each client.

[0138] The updating module 803 is configured to send the collaborative signature to the verification client to verify a portion of the signature block of each client, and update the collaborative signature according to the verification result sent by the verification client.

[0139] As an optional implementation manner, the first generating module 801 is specifically configured to: Determine the target parameters of each client in the authorized client list according to the authorized client list, the quantum resistance parameter, the first random number of the server, and the second random number of the server.

[0140] The product of the target parameters of each client in the authorized client list is used as the server's secret key.

[0141] As an optional implementation, the first generating module 801 is specifically configured to: The message to be signed is encoded into a first encoded random number, and a first auxiliary parameter of the server is determined according to the first encoded random number, a secret key of the server, and a quantum-resistant parameter.

[0142] Determine a second auxiliary parameter of the server according to the first encoded random number and the public parameter.

[0143] Arrange partial signature blocks of each client, the first auxiliary parameter of the server, and the second auxiliary parameter of the server in random order and combine them into a collaborative signature.

[0144] As an optional implementation, the updating module 803 is specifically configured to: Traverse each result in the verification result. For the current result traversed, if the partial signature block corresponding to the current result is invalid, delete the partial signature block corresponding to the current result from the collaborative signature.

[0145] Based on the same inventive concept, the embodiments of the present application also provide a quantum-resistant collaborative signature device corresponding to the quantum-resistant collaborative signature method executed by the verification client. Since the principle of solving the problem by the device in the embodiments of the present application is similar to the quantum-resistant collaborative signature method executed by the verification client in the above-mentioned embodiments of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0146] Figure 9 This is a module structure diagram of another quantum-resistant collaborative signature device provided in an embodiment of the present application, such as Figure 9 As shown, the device includes: The second generating module 901 is used to generate a private key and a public key string of the client according to the public parameters sent by the server.

[0147] The second generation module 901 is further configured to generate a partial signature block of the client according to the message to be signed and the private key and public key string of the client, and send the partial signature result of the client to the server.

[0148] The second receiving module 902 is configured to receive the collaborative signature sent by the server, and obtain a partial signature block of each client and auxiliary parameters of the server according to the collaborative signature.

[0149] Verification module 903 is used to verify whether the partial signature block of each client in the collaborative signature is valid based on the partial signature block of each client, the auxiliary parameters of the server, the authorized client list, the random number of the server and the public key string of each client, obtain the verification result, and send the verification result to the server.

[0150] As an optional implementation, the second generating module 901 is specifically configured to: Generate the client's private key and public key string based on the public parameters and the client's random number.

[0151] As an optional implementation, the second generating module 901 is specifically configured to: The quantum homomorphic encryption algorithm is used to determine the quantum-resistant random number, which is the sum of the first random numbers of each client.

[0152] Generate the client's private key based on the public parameters, the client's second random number and the quantum-resistant random number.

[0153] Generate a public key string of the client according to the public parameters, the second random number of the client, and the third random number of the client.

[0154] As an optional implementation, the second generating module 901 is specifically configured to: The message to be signed is encoded into a second encoded random number.

[0155] Generate a partial signature block of the client according to the second encoded random number, the private key and the public key string of the client.

[0156] As an optional implementation, the verification module 903 is specifically configured to: The auxiliary parameters of each client are determined according to the authorized client list, the public key string of each client, the random number of the server, and the first auxiliary parameter of the server.

[0157] The verification parameters are determined based on the authorized client list, the first random number of the server, and the public key string of each client.

[0158] Based on the partial signature block of each client, the second auxiliary parameter of the server, the auxiliary parameters of each client, the random number of the server, the verification parameter and the public key string of each client, the validity of the partial signature block of each client in the collaborative signature is verified in turn.

[0159] The embodiment of the present application also provides an electronic device, which can be the above-mentioned server or verification client. Figure 10 FIG. 1 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application, comprising: a processor 101, a memory 102 and a bus 103. The memory 102 stores machine-readable instructions executable by the processor 101 (e.g., Figure 8 The execution instructions corresponding to the first generating module 801, the first receiving module 802 and the updating module 803 in the device, or Figure 9), when the electronic device 100 is running, the processor 101 communicates with the memory 102 via the bus 103. When the machine-readable instructions are executed by the processor 101, the method steps performed by the above-mentioned server or verification client are executed.

[0160] The embodiment of the present application also provides a quantum-resistant collaborative signature system, such as Figure 1 As shown, the quantum-resistant collaborative signature system includes: a server and multiple clients communicating with the server.

[0161] The server and the verification client among the multiple clients are respectively used to execute the method steps described in the above embodiments.

[0162] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system and device described above can refer to the corresponding process in the method embodiment, and will not be repeated in this application. In the several embodiments provided in this application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0163] In addition, the functional units in the various embodiments of the present application can be integrated into a single processing unit, each unit can exist physically separately, or two or more units can be integrated into a single unit. If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the portion that contributes to the prior art, or the portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in the various embodiments of the present application. The aforementioned storage medium includes various media that can store program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0164] The above is only a specific implementation method of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the protection scope of the present application.

Claims

1. A quantum-resistant collaborative signature method, characterized in that: A method for applying to a server in a quantum-resistant collaborative signature system includes: Determine an authorized client list, and generate a secret key of the server based on the authorized client list, the quantum resistance parameter sent by the client, and the random number of the server; Receive partial signature blocks sent by each client; Determining auxiliary parameters of the server based on the message to be signed, the server's secret key, public parameters, and the quantum-resistant parameters, and generating a collaborative signature based on the auxiliary parameters and partial signature blocks of each client; The collaborative signature is sent to the verification client to verify the partial signature block of each client, and the collaborative signature is updated according to the verification result sent by the verification client.

2. The method according to claim 1, characterized in that Generating the secret key of the server according to the authorized client list, the quantum-resistant parameter sent by the client, and the random number of the server includes: Determining a target parameter for each client in the authorized client list according to the authorized client list, the quantum resistance parameter, the first random number of the server, and the second random number of the server; The product of the target parameters of each client in the authorized client list is used as the secret key of the server.

3. The method according to claim 1, characterized in that The process of determining the auxiliary parameters of the server based on the message to be signed, the secret key of the server, the public parameters, and the quantum-resistant parameters, and generating a collaborative signature based on the auxiliary parameters and a partial signature block of each client includes: Encoding the message to be signed into a first coded random number, and determining a first auxiliary parameter of the server based on the first coded random number, the secret key of the server, and the quantum-resistant parameter; Determining a second auxiliary parameter of the server according to the first encoded random number and the public parameter; Partial signature blocks of each client, the first auxiliary parameter of the server, and the second auxiliary parameter of the server are arranged in random order and combined into the collaborative signature.

4. The method according to claim 1, wherein Updating the collaborative signature according to the verification result sent by the verification client includes: Traverse each result in the verification result, and for the current result traversed, if the partial signature block corresponding to the current result is invalid, delete the partial signature block corresponding to the current result from the collaborative signature.

5. A quantum-resistant collaborative signature method, characterized in that: Applied to a client in a quantum-resistant collaborative signature system; the method comprises: Generate the client's private key and public key string based on the public parameters sent by the server; Generate a partial signature block of the client based on the message to be signed and the private key and public key string of the client, and send the partial signature result of the client to the server; Receive the collaborative signature sent by the server, and obtain the partial signature block of each client and the auxiliary parameters of the server according to the collaborative signature; Based on the partial signature blocks of each client, the auxiliary parameters of the server, the authorized client list, the random number of the server and the public key string of each client, the partial signature blocks of each client in the collaborative signature are verified in turn to see whether they are valid, and the verification results are obtained and sent to the server.

6. The method according to claim 5, characterized in that Generating the private key and public key string of the client according to the public parameters sent by the server includes: Generate a private key and a public key string of the client according to the public parameters and the random number of the client.

7. The method according to claim 6, characterized in that Generating the private key and public key string of the client according to the public parameter and the random number of each client includes: A quantum homomorphic encryption algorithm is used to determine a quantum-resistant random number, where the quantum-resistant random number is the sum of the first random numbers of each client; Generate a private key of the client according to the public parameter, the second random number of the client, and the quantum-resistant random number; Generate a public key string of the client according to the public parameter, the second random number of the client, and the third random number of the client.

8. The method according to claim 5, characterized in that Generating a partial signature block of the client according to the message to be signed and the private key and public key string of the client includes: Encoding the message to be signed into a second encoded random number; Generate a partial signature block of the client according to the second encoded random number, the private key and the public key string of the client.

9. The method according to claim 5, characterized in that The verification of the validity of the partial signature blocks of each client in the collaborative signature in sequence based on the partial signature blocks of each client, the auxiliary parameters of the server, the authorized client list, the random number of the server, and the public key string of each client includes: Determine the auxiliary parameters of each client according to the authorized client list, the public key string of each client, the random number of the server, and the first auxiliary parameter of the server; Determine verification parameters based on the authorized client list, the first random number of the server, and the public key string of each client; Based on the partial signature block of each client, the second auxiliary parameter of the server, the auxiliary parameter of each client, the random number of the server, the verification parameter and the public key string of each client, the validity of the partial signature block of each client in the collaborative signature is verified in turn.

10. A quantum-resistant collaborative signature system, characterized in that: The quantum-resistant collaborative signature system includes: a server and a plurality of clients in communication with the server; The server is used to perform the method steps according to any one of claims 1 to 4; The verification client among the multiple clients is used to perform the method steps described in any one of claims 5-9.

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