WO2020172889A1

WO2020172889A1 - Key management method in which clients separately generate key components, and electronic device

Info

Publication number: WO2020172889A1
Application number: PCT/CN2019/076587
Authority: WO
Inventors: 颜泽; 谢翔; 傅志敬; 孙立林
Original assignee: 云图有限公司
Priority date: 2019-02-28
Filing date: 2019-02-28
Publication date: 2020-09-03

Abstract

Provided are a key management method in which clients separately generate key components, and an electronic device, being applied to a key management system. The key management system comprises N clients and a key server. The method comprises: the N clients and the key server perform mutual authentication by means of an identity confirmation program, and transmit authentication material; the N clients and the key server establish secure channels on the basis of the authentication material; the N clients separately generate key components that correspond to N clients, thereby obtaining N key components; the N clients and the key server calculate and obtain a target public key on the basis of the N key components, and return the target public key to the N clients and the key server. The method described above solves the problem of existing key management having low security and flexibility, and achieves the technical effect of efficiently enhancing key security and flexibility.

Description

Key management method and electronic device for generating key components separately by clients

Technical field

This application belongs to the field of information security technology, and in particular relates to a key management method and electronic equipment for each client to generate key components.

Background technique

At present, for the key service system, a key server generally generates the key, and then distributes the generated key to the key users. This will inevitably increase the burden on the key server, and because a single key server The key server generates all key generation rules, which are specified and maintained by the key server itself, which is not flexible.

Aiming at the above-mentioned problems existing in the existing key system, no effective solution has been proposed at present.

Summary of the invention

The purpose of this application is to provide a key management method and electronic device for each client to generate key components, which can effectively improve the security of the key management system and the flexibility of key management.

The present application provides a key management method and electronic device for generating key components by each client, which is implemented as follows:

A key management method for each client to generate key components is applied to a key management system, wherein the key management system includes: N clients and a key server, and the method includes:

The N clients and the key server complete mutual authentication through an identity confirmation procedure, and issue authentication materials;

The N clients and the key server establish a secure channel according to the authentication material;

Each of the N clients generates their own corresponding key components to obtain N key components;

The N clients and the key server calculate a target public key according to the N key components, and return the target public key to the N clients and the key server.

In one embodiment, the N clients and the key server calculate the target public key according to the N key components, and return the target public key to the N clients and all The key server includes:

The N clients calculate the public key components according to the key components generated by them, and obtain N public key components;

Selecting a client from the N clients as the first client, where the first client is an MPC computing party, and the public key component generated by the first client is used as an encryption component;

A client other than the first client among the N clients splits the key component generated by itself into a first key sub-component and a second key sub-component, and uses the encrypted component pair The first key subcomponent and the public key component are encrypted to obtain N-1 key ciphertexts and N-1 public key ciphertexts;

Sending the N-1 key ciphertext and N-1 public key ciphertext to the key server;

Sending, by the key server, the N-1 key ciphertext, N-1 first key subcomponent plaintext, and N-1 public key ciphertext to the first client through a secure channel;

The first client decrypts the N-1 key ciphertext and N-1 public key ciphertext to obtain N-1 key subcomponents and N-1 public key components, and use all The encrypted component signs the N-1 public key components to obtain N-1 signature components;

The first client and the key server initiate an MPC calculation through the secure channel to obtain a target public key, and return the target public key to the N clients and the key server.

In one embodiment, the N clients and the key server calculate the target public key according to the N key components, and return the target public key to the N clients and After the key server, it also includes:

The first client initiates a signature request, wherein the signature request carries data to be signed;

A client other than the first client among the N clients splits the key component generated by itself into a first key sub-component and a second key sub-component, and uses the encrypted component pair The first key subcomponent is encrypted to obtain N-1 key ciphertexts;

Clients other than the first client among the N clients send the N-1 key ciphertext and N-1 second key subcomponent plaintext to the key server;

Sending, by the key server, the N-1 key ciphertext to the first client through a secure channel;

The first client decrypts the N-1 key ciphertext to obtain N-1 key subcomponents;

The first client and the key server initiate an MPC calculation through the secure channel, sign the data to be signed, and return the signature result to the N clients and the key server.

Each of the N clients obtains a backup key through a backup method;

Calculating the hash value of the backup key, and sending the hash value to the key server;

The key server verifies the correctness of the hash value, and returns the target public key if the verification is passed.

The key server generates a service key component;

The N clients and the key server initiate an MPC calculation through the secure channel, and the target public key is obtained by calculation.

The first client initiates a signature request, where the signature request carries data to be signed, and the first client is one of the N clients;

The N clients and the key server initiate MPC calculations through the secure channel, sign the data to be signed, and verify the correctness of the signature result through the target public key.

The N clients and the key server initiate an MPC calculation through the secure channel to obtain N+1 backup key components, and sign the N+1 backup key components to obtain N+ 1 backup signature component;

Sending the N+1 backup key components and N backup signature components in a one-to-one correspondence to each of the N clients and the key server;

The N clients and the key server verify the validity of the received backup signature component through the target public key, and if the verification is passed, save the received backup key component.

Receive a restoration request from a restoration requester, where the restoration requester is one of the N clients, and the restoration request carries the key component of the restoration requester and the target public key ；

Clients other than the restore requester among the N clients obtain their own backup key components through a backup method;

The N clients and the key server initiate an MPC calculation to generate a verification public key through the secure channel, and determine whether the verification public key is the same as the target public key, and if it is determined to be the same, proceed MPC calculates to obtain N+1 restoration key components, and signs the N+1 restoration key components to obtain N+1 restoration signature components;

Sending the N+1 restoration key components and the N+1 restoration signature components to the N clients and the key server in a one-to-one correspondence;

The N clients and the key server verify the validity of the received restoration signature component through the target public key, and if the verification is passed, update and save the received restoration key component.

The N clients and the key server initiate an MPC calculation through the secure channel to obtain N+1 refresh key components, and sign the N+1 refresh key components to obtain N+ 1 refresh signature component;

Sending the N+1 refresh key components and N refresh signature components in a one-to-one correspondence to each of the N clients and the key server;

The N clients and the key server verify the validity of the received refresh signature component through the target public key, and if the verification passes, save the received refresh key component.

An electronic device includes a processor and a memory for storing executable instructions of the processor, and the processor implements the steps of the following method when executing the instructions:

A computer-readable storage medium having computer instructions stored thereon, which implement the steps of the following method when the instructions are executed:

This application provides a key management method and electronic device for each client to generate a key component. Each client in the key management system generates its own key component locally, and finally generates a target public key based on the key component to achieve Key generation. Through the above method, the problem of low security and low flexibility in the existing key management is solved, and the technical effect of effectively improving the security and flexibility of the key is achieved.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments described in this application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.

Figure 1 is an architectural diagram of the key system provided by this application;

FIG. 2 is a flowchart of a key management method for a client to generate key components for each client provided by this application;

Figure 3 is a schematic diagram of the interaction of the key generation of Example 1 provided by this application;

Figure 4 is a schematic diagram of the interaction of the key usage of Example 1 provided by the present application;

Figure 5 is a schematic diagram of the interaction of the key backup of Example 1 provided by this application;

6 is a schematic diagram of the interaction of the key recovery of Example 1 provided by this application;

FIG. 7 is a schematic diagram of the interaction of the key generation of Example 2 provided by this application;

FIG. 8 is a schematic diagram of the interaction of the key usage of Example 2 provided by this application;

FIG. 9 is a schematic diagram of the interaction of the key backup of Example 2 provided by the present application;

FIG. 10 is a schematic diagram of the interaction of the key recovery of Example 2 provided by this application;

FIG. 11 is a schematic diagram of the interaction of the key refresh of Example 2 provided by the present application;

FIG. 12 is a schematic diagram of the structure of the electronic device provided by the present application.

detailed description

In order to enable those skilled in the art to better understand the technical solutions in the application, the following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Obviously, the described The embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

Considering that the existing key server generates the key unilaterally, which leads to the problem of low flexibility and security. In this example, each client in the key management system generates its own key component locally, which is finally based on The key component generates the target public key to achieve key generation. When in use, the client and the key server use these key components to perform operations such as signing and updating, thereby improving the flexibility of key generation and the security of the key.

In this example, the key management method for each client to generate a key component is applied to a key management system. The key management system may be as shown in Figure 1, including: N clients and a key server , Where N is a positive integer greater than or equal to 2.

Fig. 2 is a method flowchart of an embodiment of a key management method for each client to generate a key component according to the present application. Although this application provides method operation steps or device structures as shown in the following embodiments or drawings, the method or device may include more or fewer operation steps or module units based on conventional or no creative labor. . In steps or structures where there is no necessary causal relationship logically, the execution order of these steps or the module structure of the device is not limited to the execution order or module structure shown in the description of the embodiments of this application and the drawings. When the described method or module structure is applied to an actual device or terminal product, it can be executed sequentially or in parallel according to the method or module structure connection shown in the embodiments or drawings (for example, parallel processor or multi-threaded processing Environment, even distributed processing environment).

Specifically, as shown in FIG. 2, a key management method for each client to generate key components provided by an embodiment of the present application may include the following steps:

Step 201: N clients and the key server complete mutual authentication through an identity confirmation procedure, and issue authentication materials;

Among them, the above-mentioned client is a key user, including but not limited to App, application server, etc. The specific form of the client can be selected according to actual needs, and this application does not limit this. The above-mentioned key server is a key service party and is used to provide key related services.

Step 202: N clients and the key server establish a secure channel according to the authentication material;

The above-mentioned secure channel may be established after completing mutual authentication based on KYC (Know your customer, identity confirmation procedure). Wherein, the identity confirmation procedure may include but is not limited to at least one of the following: mobile phone short message, email verification code, account password, fingerprint, face, certificate, etc.

Step 203: N clients each generate their own corresponding key components to obtain N key components;

For example: Client 1 generates key components SK1, S3: Clients 2 to n locally generate key components SK2 to n.

Step 204: N clients and the key server calculate a target public key according to the N key components, and return the target public key to the N clients and the key server.

Specifically, in step 204, the target public key may be generated by a two-party MPC (Secure Multi-Party Computation), or the target public key may be generated by a multi-party MPC. Two-party MPC means that any two of the devices perform MPC calculations, and multi-party MPC means that all devices in the device participate in MPC calculations.

MPC is how two millionaires can compare who is richer without revealing their true property status without a trusted third party. MPC can ensure the data security of all parties, and at the same time, jointly use the data of all parties to achieve specific effects, so as to give full play to the value of data. Multiple participants holding their own private data jointly execute a calculation logic calculation logic (such as a maximum value calculation) and obtain the calculation result. However, in the process, each party participating in the calculation will not leak their own data, which is called MPC calculation. MPC calculation can design the protocol without relying on a trusted third party. Secure multi-party computing can be abstractly understood as: two parties have their own private data, and can calculate the result of the public function without leaking their private data. When the entire calculation is completed, only the calculation result is known to both parties, and neither party knows the other's data and the intermediate data of the calculation process.

The following describes the key generation, use, backup, and refresh of the two-party MPC:

The key component and target private key generated by the two-party MPC may include the following steps:

S1: N clients calculate the public key components according to the key components they generate, and obtain N public key components;

S2: Select a client from the N clients as the first client, where the first client is an MPC computing party, and the public key component generated by the first client is used as an encryption component;

S3: A client other than the first client among the N clients splits the key component generated by itself into a first key sub-component and a second key sub-component, and passes the encryption The component encrypts the first key subcomponent and the public key component to obtain N-1 key ciphertexts and N-1 public key ciphertexts;

S4: Send the N-1 key ciphertext and N-1 public key ciphertext to the key server;

S5: The key server sends the N-1 key ciphertext, N-1 first key subcomponent plaintext, and N-1 public key ciphertext to the first client through a secure channel;

S6: The first client decrypts the N-1 key ciphertext and N-1 public key ciphertext to obtain N-1 key subcomponents and N-1 public key components, and use all The encrypted component signs the N-1 public key components to obtain N-1 signature components;

S7: The first client and the key server initiate an MPC calculation through the secure channel to obtain a target public key, and return the target public key to the N clients and the key server.

That is, in the process of generating the target public key, not only the secure channel and MPC calculation are used, but also the ciphertext of the data is generated, so that the security of the data in the data transmission and data calculation process can be guaranteed at the same time.

After the key component and target private key are generated by the two-party MPC, you can sign according to the following steps:

S1: The first client initiates a signature request, where the signature request carries data to be signed;

S2: A client other than the first client among the N clients splits the key component generated by itself into a first key sub-component and a second key sub-component, and uses the encryption component pair The first key subcomponent is encrypted to obtain N-1 key ciphertexts;

S3: Clients other than the first client among the N clients send the N-1 key ciphertext and N-1 second key subcomponent plaintext to the key server;

S4: The key server sends the N-1 key ciphertext to the first client through a secure channel;

S5: The first client decrypts the N-1 key ciphertext to obtain N-1 key subcomponents;

S6: The first client and the key server initiate an MPC calculation through the secure channel, sign the data to be signed, and return the signature result to the N clients and the key server.

After generating the key component and the target private key through the two-party MPC, the key component can be backed up as follows:

S1: Each of the N clients obtains the backup key through a backup method;

S2: Calculate the hash value of the backup key, and send the hash value to the key server;

S3: The key server verifies the correctness of the hash value, and returns the target public key if the verification is passed.

Generating key components through multi-party MPC may include the following steps:

S1: The key server generates the service key component;

S2: N clients and the key server initiate an MPC calculation through the secure channel, and the target public key is obtained by calculation.

After generating the key component and the target private key through the two-party MPC, you can sign according to the following steps:

S1: The first client initiates a signature request, where the signature request carries data to be signed, and the first client is one of the N clients;

S2: N clients and the key server initiate an MPC calculation through the secure channel, sign the data to be signed, and verify the correctness of the signature result through the target public key.

After the key component and target private key are generated by the two-party MPC, you can back up or refresh according to the following steps:

S1: The N clients and the key server initiate MPC calculation through the secure channel to obtain N+1 backup key components (or refresh key components), and back up the N+1 copies Sign the key component (or refresh key component) to obtain N+1 backup signature components (or refresh signature components);

S2: Send the N+1 backup key components (or refresh key components) and N backup signature components (or refresh signature components) to each of the N clients in a one-to-one correspondence And key server;

S3: N clients and the key server verify the validity of the received backup signature component (or refresh signature component) through the target public key, and if the verification is passed, save the received backup key component (Or refresh the key component).

After generating the key component and the target private key through the two-party MPC, you can follow the steps below to recover:

S1: Receive a recovery request from a recovery requester, where the recovery requester is one of the N clients, and the recovery request carries the key component of the recovery requester and the target Public key

S2: Clients other than the restore requester among the N clients obtain their own backup key components through a backup method;

S3: N clients and the key server initiate MPC calculation to generate a verification public key through the secure channel, and determine whether the verification public key is the same as the target public key, and if it is determined to be the same, proceed MPC calculates to obtain N+1 restoration key components, and signs the N+1 restoration key components to obtain N+1 restoration signature components;

S4: Send N+1 restoration key components and the N+1 restoration signature components to the N clients and the key server in a one-to-one correspondence;

S5: N clients and the key server verify the validity of the received restoration signature component through the target public key, and if the verification is passed, update and save the received restoration key component.

The above method will be described below in conjunction with several specific examples. However, it is worth noting that this specific example is only to better illustrate the application and does not constitute an improper limitation of the application.

Example 1

In this example, a method for key management based on secure two-party calculations generated and kept by multiple clients on a server is provided. Specifically, different clients independently generate key components and finally use two-party MPC to generate public keys. , Through the two-party MPC using the client and the key server to calculate the signature.

Based on this, operations such as key generation, use, storage, backup, and restoration in the key management system can be performed as follows:

1) Generate

As shown in Figure 3, the following steps can be included:

S1: Client 1 generates key component SK1, and calculates public key PK1 through SK1;

S2: Client 1 and the key server complete mutual authentication through KYC to complete the registration operation, and initiate a key generation request;

S3: Clients 2 to n obtain the generation request of client 1 through query respectively, and locally generate key components SK2 to n, and calculate public keys PK2 to n;

S4: Clients 2～n complete mutual authentication with the key server through KYC respectively to complete the registration operation, then split SK2 into SK2-1 and SK2-2, and encrypt SK2-1 and PK2 with PK1. And send PK1 (SK2-1) ciphertext, PK1 (PK2) ciphertext and SK2-2 plaintext to the key server. By analogy, SKn is split into SKn-1 and SKn-2, SKn-2 and PKn are encrypted with PK1, and PK1 (SKn-1) ciphertext, PK1 (PKn) ciphertext and SKn-2 are transmitted in plaintext. To the key server;

S5: The key server sends the cipher text information PK1(SK2-1), PK1(SK3-1)...PK1(Skn-1) and PK1(PK2)...PK1(PKn) through the secure channel Client 1

S6: Client 1 decrypts to obtain SK2-1, SK3-1...SKn-1 and PK2, PK3...PKn, and then signs PK2...PKn with SK1 to obtain signature content S2...Sn;

S7: Client 1 sends PK2...PKn plaintext and signatures S2...Sn to the key server for storage;

S8: The client 1 and the key server authenticate through the authentication material and establish a secure channel, and initiate MPC calculation: calculate the private key SK through the key components SK1 to n, and calculate the public key PK through the private key SK. And return the public key PK to the client and the key server and save them separately. Because the entire process is a complete MPC calculation, the private key SK has not actually been generated (either during calculation or during use), and SK1～n did not appear in the process of computing interaction (that is, not in the network Layer transmission SK1-n is used for calculation).

2) use

As shown in Figure 4, the following steps can be included:

S1: Client 1 initiates a signature request and provides the public key PK as a unique identifier and data to be signed;

S2: The client 2～n and the key server complete mutual authentication through KYC and establish a secure channel. Then, SK2 is split into SK2-1 and SK2-2, and SK2-1 is encrypted using PK1. And send the ciphertext of PK1 (SK2-1) and the plaintext of SK2-2 to the key server. By analogy, SKn is split into SKn-1 and SKn-2, SKn-2 is encrypted with PK1, and the ciphertext of PK1 (SKn-1) and SKn-2 are transmitted to the key server;

S3: The key server sends the cipher text information PK1 (SK2-1), PK1 (SK3-1)...PK1 (Skn-1) to the client 1 through the secure channel;

S4: Client 1 decrypts to obtain SK2-1, SK3-1...SKn-1;

S5: The client 1 and the key server establish a secure channel through authentication material authentication, and initiate MPC calculation: the private key SK is calculated through the key components SK1 to n, and the private key SK is used to sign the data to be signed. Return the signature to the client and the key server. Because the entire process is a complete MPC calculation, the private key SK has not actually been generated (either during calculation or during use), and SK1～n did not appear in the process of computing interaction (that is, not in the network Layer transmission SKs, SK1～n are used for calculation).

3) storage

The key or key component can be stored in one of the following forms, but not limited to:

Database: Save the key or key component through the database, where the key or key component can be encrypted and stored;

Key file: save the key or key component by exporting the key file, where the key or key component can be encrypted and stored;

HSM: Save the key or key component through the hardware security module, where the key or key component can be encrypted and stored;

Mnemonic: Convert the key and the key component to generate a series of mnemonics for storage;

Two-dimensional code: The corresponding two-dimensional code is generated by the key or key component for storage, where the key or key component can be encrypted and stored.

4) backup

As shown in Figure 5, in the process of generating the key components SK1-n, the client directly backs up the key components SK1-n.

5) Recovery

As shown in Figure 6, the following steps can be included:

S1: The client obtains the backup key through the backup method, and sends the key calculation hash value to the key server to initiate a key recovery request;

S2: After receiving the recovery request, the key server verifies the correctness of the hash value, and if it is correct, returns the public key PK.

Example 2

In this example, a method for key management based on secure multi-party calculations generated and stored by multiple clients on a server is provided. Specifically, multiple clients and key servers respectively generate private key components through MPC calculations. The public key uses multiple clients and key servers to calculate the signature through MPC, and uses the private key component of a certain client to perform MPC calculation to refresh the components of multiple clients and key servers.

Based on this, operations such as key generation, use, storage, backup, restoration, and refresh in the key management system can be performed as follows:

1) Generate

As shown in Figure 7, the following steps can be included:

S1: The client and the key server complete two-way authentication through KYC, and issue authentication materials to complete the registration process;

S2: Clients generate and save key components respectively, for example: client 1 generates key component SK1, client 2 generates key component SK2; and so on, client n generates key component SKn;

S3: After receiving the key generation request, the key server generates and saves the key component SKs;

S4: The client and the key server establish a secure channel through authentication material authentication, and initiate MPC calculation: calculate the private key SK through the key components SKs, SK1～n, and calculate the public key PK through the private key SK. The public key is returned to the client and the key server, and the client and the key server are stored separately. Because the entire process is a complete MPC calculation, the private key SK has not actually been generated (either during calculation or during use), and SKa and SK1～n did not appear in the calculation interaction process (that is, no SKs, SK1～n are transmitted at the network layer for calculation).

2) use

As shown in Figure 8, the following steps can be included:

S2: The client and the key server complete mutual authentication and establish a secure channel through KYC;

S3: The client and the key server initiate an MPC calculation through a secure channel: perform a signature operation on the data to be signed, and verify the correctness of the signature through the PK public key.

3) storage

4) backup

As shown in Figure 9, the following steps can be included:

S1: Client 1 initiates a backup key request, completes two-way authentication through KYC and establishes a secure channel;

S2: The client and the key server initiate MPC calculations through a secure channel: generate a private key SK, and generate SK1～SKn+1 through the secret sharing algorithm, use SK to sign SK1～SKn+1, and generate signatures S1～Sn+1 . Distribute the signatures to different key servers and clients. For example: issue SK1, S1 to client 1; issue SK2, S2 to client 2; and so on, issue SKn, Sn to client n; SKn+1, Sn+1 to the key server. Because the entire process is a complete MPC calculation, the private key SK has not actually been generated (either during the calculation process or during use);

S3: Each client and key server verifies the validity of the received signature component through the previously stored public key PK, and if it is valid, saves the received key component for backup.

5) Recovery

As shown in Figure 10, the following steps can be included:

S1: Assuming that client 1 needs to restore the key, obtain the backup key through backup, and use the backup key components SK1 and PK to initiate a key restoration request;

S2: Clients 2 to n receive the key recovery request initiated by client 1 and agree. Then each obtain the backup key through the backup method, and provide SK2～SKn to cooperate with the recovery key;

S3: The client and the key server complete mutual authentication and establish a secure channel through KYC;

S4: The client and the key server initiate an MPC calculation through the secure channel to verify whether the backup component is correct: calculate the private key SK, and generate the public key PK through the SK. If the PK is the same as the stored PK, the verification is passed. If the verification is passed, the MPC calculates the recovery key component: calculates the private key SK, generates SK1～SKn+1 through the secret sharing algorithm, and uses SK to sign SK1～SKn+1 to generate signatures S1～Sn+1. Send the signatures to different clients and key servers, for example: send SK1 and S1 to client 1; send SK2 and S2 to client 2; and so on, send SKn and Sn to client n ; SKn+1, Sn+1 to the key server. Because the entire process is a complete MPC calculation, the private key SK has not actually been generated (either during the calculation process or during use);

S5: Each client and the key server verify the validity of the signature through the previously stored public key PK, and if it is valid, update and save the key component.

6) refresh

As shown in Figure 11, the following steps can be included:

S1: The client or key server initiates a key refresh request, completes two-way authentication through KYC and establishes a secure channel;

S2: The client and the key server initiate MPC calculations through a secure channel: generate a private key SK, and generate SK1～SKn+1 through the secret sharing algorithm, use SK to sign SK1～SKn+1, and generate signatures S1～Sn+1 . Send the signatures to different clients and key servers, for example: send SK1 and S1 to client 1; send SK2 and S2 to client 2; and so on, send SKn and Sn to client n ; SKn+1, Sn+1 to the key server. Because the entire process is a complete MPC calculation, the private key SK has not actually been generated (whether in the calculation process or in use);

S3: Each client and the key server verify the validity of the signature through the previously stored public key PK, and if it is valid, update and save the key component.

The method embodiments provided in the foregoing embodiments of the present application may be executed in a mobile terminal, a computer terminal, or a similar computing device. Taking the operation on an electronic device as an example, FIG. 12 is a hardware structural block diagram of an electronic device of a key management method for each client to generate a key component in an embodiment of the present invention. As shown in FIG. 12, the electronic device 10 may include one or more (only one is shown in the figure) processor 102 (the processor 102 may include, but is not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA) , A memory 104 for storing data, and a transmission module 106 for communication functions. A person of ordinary skill in the art can understand that the structure shown in FIG. 12 is only for illustration, and does not limit the structure of the above electronic device. For example, the electronic device 10 may also include more or fewer components than those shown in FIG. 12, or have a different configuration from that shown in FIG.

The memory 104 can be used to store software programs and modules of application software, such as the program instructions/modules corresponding to the key management method for generating key components of the client in the embodiment of the present invention. The processor 102 runs the program stored in the memory 104 Software programs and modules to execute various functional applications and data processing, that is, to implement the key management method of each client generating the key components of the above-mentioned application. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely provided with respect to the processor 102, and these remote memories may be connected to the computer terminal 10 via a network. Examples of the aforementioned networks include but are not limited to the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

The transmission module 106 is used to receive or send data via a network. The above-mentioned specific examples of the network may include a wireless network provided by the communication provider of the computer terminal 10. In one example, the transmission module 106 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In an example, the transmission module 106 may be a radio frequency (RF) module, which is used to communicate with the Internet in a wireless manner.

The embodiment of the present application also provides a specific implementation manner of an electronic device that can implement all the steps in the key management method for each client generating a key component in the foregoing embodiment, and the electronic device specifically includes the following content: a processor (processor), memory (memory), communication interface (Communications Interface), and bus; wherein the processor, memory, and communication interface communicate with each other through the bus; the processor is used to call the A computer program, when the processor executes the computer program, all the steps in the key management method for each client generating a key component in the above embodiments are implemented. For example, when the processor executes the computer program, the following The steps described:

Step 1: N clients and the key server complete the mutual authentication through the identity confirmation procedure, and issue authentication materials;

Step 2: The N clients and the key server establish a secure channel according to the authentication material;

Step 3: The N clients each generate their own key components to obtain N key components;

Step 4: The N clients and the key server calculate the target public key according to the N key components, and return the target public key to the N clients and the key server.

It can be seen from the above description that the key management method and electronic device for each client to generate a key component provided by the embodiments of the present application, each client in the key management system generates its own key component locally, which is finally based on the key component Generate the target public key to achieve key generation. Through the above method, the problem of low security and low flexibility in the existing key management is solved, and the technical effect of effectively improving the security and flexibility of the key is achieved.

The embodiment of the present application also provides a computer-readable storage medium capable of implementing all the steps in the key management method for each client generating a key component in the above-mentioned embodiment, and the computer-readable storage medium stores a computer program When the computer program is executed by the processor, all the steps of the key management method for the client to generate key components in the above embodiments are implemented. For example, when the processor executes the computer program, the following steps are implemented:

The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the hardware+program embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and for related parts, please refer to the part of the description of the method embodiment.

The foregoing describes specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims may be performed in a different order than in the embodiments and still achieve desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or sequential order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

Although this application provides method operation steps as described in the embodiments or flowcharts, conventional or uninvented labor may include more or fewer operation steps. The sequence of steps listed in the embodiment is only one way of the execution sequence of the steps, and does not represent the only execution sequence. When an actual device or a client product is executed, it can be executed sequentially or in parallel according to the methods shown in the embodiments or drawings (for example, a parallel processor or a multi-threaded environment).

The systems, devices, modules, or units illustrated in the above embodiments may be specifically implemented by computer chips or entities, or implemented by products with certain functions. A typical implementation device is a computer. Specifically, the computer may be, for example, a personal computer, a laptop computer, a vehicle-mounted human-computer interaction device, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, and a tablet. Computers, wearable devices, or any combination of these devices.

Although the embodiments of this specification provide method operation steps as described in the embodiments or flowcharts, conventional or non-inventive means may include more or fewer operation steps. The sequence of steps listed in the embodiment is only one way of the execution sequence of the steps, and does not represent the only execution sequence. When an actual device or terminal product is executed, it can be executed sequentially or in parallel according to the methods shown in the embodiments or drawings (for example, a parallel processor or multi-threaded processing environment, or even a distributed data processing environment). The terms "include", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, product, or device that includes a series of elements includes not only those elements, but also other elements that are not explicitly listed. Elements, or also include elements inherent to such processes, methods, products, or equipment. If there are no more restrictions, it does not exclude that there are other identical or equivalent elements in the process, method, product, or device including the elements.

For the convenience of description, when describing the above device, the functions are divided into various modules and described separately. Of course, when implementing the embodiments of this specification, the function of each module can be implemented in the same one or more software and/or hardware, or a module that implements the same function can be implemented by a combination of multiple sub-modules or sub-units. The device embodiments described above are merely illustrative, for example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components can be combined or integrated To another system, or some features can be ignored, or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.

Those skilled in the art also know that in addition to implementing the controller in a purely computer-readable program code manner, it is entirely possible to program the method steps to make the controller use logic gates, switches, application specific integrated circuits, programmable logic controllers and embedded The same function can be realized in the form of a microcontroller, etc. Therefore, such a controller can be regarded as a hardware component, and the devices included in the controller for realizing various functions can also be regarded as a structure within the hardware component. Or even, the device for realizing various functions can be regarded as both a software module for realizing the method and a structure within a hardware component.

The present invention is described with reference to flowcharts and/or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and/or block in the flowchart and/or block diagram, and the combination of processes and/or blocks in the flowchart and/or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing equipment to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing equipment are generated It is a device that realizes the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing equipment to work in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction device. The device implements the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

These computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operation steps are executed on the computer or other programmable equipment to produce computer-implemented processing, so as to execute on the computer or other programmable equipment. The instructions provide steps for implementing functions specified in a flow or multiple flows in the flowchart and/or a block or multiple blocks in the block diagram.

In a typical configuration, the computing device includes one or more processors (CPU), input/output interfaces, network interfaces, and memory.

The memory may include non-permanent memory in computer readable media, random access memory (RAM) and/or non-volatile memory, such as read-only memory (ROM) or flash memory (flash RAM). Memory is an example of computer readable media.

Computer-readable media include permanent and non-permanent, removable and non-removable media, and information storage can be realized by any method or technology. The information can be computer readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, CD-ROM, digital versatile disc (DVD) or other optical storage, Magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media can be used to store information that can be accessed by computing devices. According to the definition in this article, computer-readable media does not include transitory media, such as modulated data signals and carrier waves.

Those skilled in the art should understand that the embodiments of this specification can be provided as methods, systems or computer program products. Therefore, the embodiments of this specification may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the embodiments of this specification may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

The embodiments of this specification may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The embodiments of this specification can also be practiced in distributed computing environments. In these distributed computing environments, tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in local and remote computer storage media including storage devices.

The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, as for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and for related parts, please refer to the part of the description of the method embodiment. In the description of this specification, descriptions with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean specific features described in conjunction with the embodiment or example , Structure, materials or features are included in at least one embodiment or example of the embodiments of this specification. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples and the characteristics of the different embodiments or examples described in this specification without contradicting each other.

The above descriptions are only examples of the embodiments of this specification, and are not used to limit the embodiments of this specification. For those skilled in the art, various modifications and changes are possible in the embodiments of this specification. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments of this specification should be included in the scope of the claims of the embodiments of this specification.

Claims

A key management method for each client to generate a key component is applied in a key management system, wherein the key management system includes: N clients and a key server, characterized in that the method include:

The N clients and the key server complete mutual authentication through an identity confirmation procedure, and issue authentication materials;

The N clients and the key server establish a secure channel according to the authentication material;

Each of the N clients generates their own corresponding key components to obtain N key components;

The N clients and the key server calculate a target public key according to the N key components, and return the target public key to the N clients and the key server.
The method according to claim 1, wherein the N clients and the key server calculate the target public key according to the N key components, and return the target public key to the The N clients and the key server include:

The N clients calculate the public key components according to the key components generated by them, and obtain N public key components;

Selecting a client from the N clients as the first client, where the first client is an MPC computing party, and the public key component generated by the first client is used as an encryption component;

A client other than the first client among the N clients splits the key component generated by itself into a first key sub-component and a second key sub-component, and uses the encrypted component pair The first key subcomponent and the public key component are encrypted to obtain N-1 key ciphertexts and N-1 public key ciphertexts;

Sending the N-1 key ciphertext and N-1 public key ciphertext to the key server;

Sending, by the key server, the N-1 key ciphertext, N-1 first key subcomponent plaintext, and N-1 public key ciphertext to the first client through a secure channel;

The first client decrypts the N-1 key ciphertext and N-1 public key ciphertext to obtain N-1 key subcomponents and N-1 public key components, and use all The encrypted component signs the N-1 public key components to obtain N-1 signature components;

The first client and the key server initiate an MPC calculation through the secure channel to obtain a target public key, and return the target public key to the N clients and the key server.
The method according to claim 2, wherein the N clients and the key server calculate the target public key according to the N key components, and return the target public key to After the N clients and the key server, it further includes:

The first client initiates a signature request, wherein the signature request carries data to be signed;

A client other than the first client among the N clients splits the key component generated by itself into a first key sub-component and a second key sub-component, and uses the encrypted component pair The first key subcomponent is encrypted to obtain N-1 key ciphertexts;

Clients other than the first client among the N clients send the N-1 key ciphertext and N-1 second key subcomponent plaintext to the key server;

Sending, by the key server, the N-1 key ciphertext to the first client through a secure channel;

The first client decrypts the N-1 key ciphertext to obtain N-1 key subcomponents;

The first client and the key server initiate an MPC calculation through the secure channel, sign the data to be signed, and return the signature result to the N clients and the key server.
The method according to claim 2, wherein the N clients and the key server calculate the target public key according to the N key components, and return the target public key to After the N clients and the key server, it further includes:

Each of the N clients obtains a backup key through a backup method;

Calculating the hash value of the backup key, and sending the hash value to the key server;

The key server verifies the correctness of the hash value, and returns the target public key if the verification is passed.
The method according to claim 1, wherein the N clients and the key server calculate the target public key according to the N key components, and return the target public key to the The N clients and the key server include:

The key server generates a service key component;

The N clients and the key server initiate an MPC calculation through the secure channel, and the target public key is obtained by calculation.
The method according to claim 5, wherein the N clients and the key server calculate the target public key according to the N key components, and return the target public key to After the N clients and the key server, it further includes:

The first client initiates a signature request, where the signature request carries data to be signed, and the first client is one of the N clients;

The N clients and the key server initiate MPC calculations through the secure channel, sign the data to be signed, and verify the correctness of the signature result through the target public key.
The method according to claim 5, wherein the N clients and the key server calculate the target public key according to the N key components, and return the target public key to After the N clients and the key server, it further includes:

The N clients and the key server initiate an MPC calculation through the secure channel to obtain N+1 backup key components, and sign the N+1 backup key components to obtain N+ 1 backup signature component;

Sending the N+1 backup key components and N backup signature components in a one-to-one correspondence to each of the N clients and the key server;

The N clients and the key server verify the validity of the received backup signature component through the target public key, and if the verification is passed, save the received backup key component.
The method according to claim 5, wherein the N clients and the key server calculate the target public key according to the N key components, and return the target public key to After the N clients and the key server, it further includes:

Receive a restoration request from a restoration requester, where the restoration requester is one of the N clients, and the restoration request carries the key component of the restoration requester and the target public key ；

Clients other than the restore requester among the N clients obtain their own backup key components through a backup method;

The N clients and the key server initiate an MPC calculation to generate a verification public key through the secure channel, and determine whether the verification public key is the same as the target public key, and if it is determined to be the same, proceed MPC calculates to obtain N+1 restoration key components, and signs the N+1 restoration key components to obtain N+1 restoration signature components;

Sending the N+1 restoration key components and the N+1 restoration signature components to the N clients and the key server in a one-to-one correspondence;

The N clients and the key server verify the validity of the received restoration signature component through the target public key, and if the verification is passed, update and save the received restoration key component.
The method according to claim 5, wherein the N clients and the key server calculate the target public key according to the N key components, and return the target public key to After the N clients and the key server, it further includes:

The N clients and the key server initiate an MPC calculation through the secure channel to obtain N+1 refresh key components, and sign the N+1 refresh key components to obtain N+ 1 refresh signature component;

Sending the N+1 refresh key components and N refresh signature components in a one-to-one correspondence to each of the N clients and the key server;

The N clients and the key server verify the validity of the received refresh signature component through the target public key, and if the verification passes, save the received refresh key component.
An electronic device comprising a processor and a memory for storing executable instructions of the processor, and the processor implements the steps of the method according to any one of claims 1 to 9 when the processor executes the instructions.
A computer-readable storage medium having computer instructions stored thereon, which implement the steps of the method in any one of claims 1 to 9 when the instructions are executed.