Signature method, device and system based on secure multi-party computing

Technical field of a signature method, device and system based on secure multi-party calculation

[0001] The solution of this embodiment belongs to the field of information security technology, and in particular relates to a signature method, device, and system based on secure multi-party computing.

Background technique

[0002] Secure Multi-Party Computation (MPC) is to solve the problem of collaborative computing that protects privacy between a group of untrusted parties. It can be abstractly understood as: each participant has its own private data, and calculates the public function without leaking their private data, and when the entire function calculation is completed, each participant only knows the calculation result, and does not know the other Participant's data and intermediate data of the calculation process. It can be seen that the application of secure multi-party computing to the security of asset transactions and the management of digital assets in the future has an important role.

[0003] At present, in digital asset management and asset transactions, the dynamic signature method based on secure multi-party computing is to divide the private key in the asymmetric key into two pieces, one piece for the institution and one piece for the user, only the institution and the individual share the same. Signing is required to complete the transaction process. Although this solution can largely alleviate the security problem of a single key being lost and stolen, in an extreme case: when the keys of individuals and institutions are both stolen, the security of assets cannot be guaranteed. It can be seen that the existing widely used asymmetric key scheme still has great security problems.

[0004] Therefore, there is an urgent need in the industry for a solution that can effectively solve the loss or theft of the private key.

Summary of the invention

[0005] The purpose of this embodiment is to provide a signature method, device, and system based on secure multi-party calculation, which can effectively solve the security risks of loss or theft of private keys, and greatly improve transaction security.

[0006] On the one hand, this application provides a signature method based on secure multi-party computing, including:

[0007] Obtain transaction data, and generate a transaction hash using preset rules for the transaction data;

[0008] Determine the signature level of the transaction data according to the relationship between the transaction amount in the transaction data and the first threshold;

[0009] Based on the signature level, a signature authority is determined, and the signature authority is a trusted authority that signs the transaction data;

[0010] Based on the private key fragments saved by the determined signature authority and the private key fragments saved by the client, signature verification based on secure multi-party calculation is performed on the transaction hash, wherein the trusted authority and the The client separately saves private key fragments, and the private key fragments are composed of partial sub-private keys generated based on splitting the asymmetric key.

[0011] In another embodiment of the method provided by the present invention, the trusted organization and the client separately store private key fragments, including:

[0012] Generate at least two pairs of asymmetric keys during the registration process;

[0013] segmenting the private key in the asymmetric key to obtain a first segment of the private key and a second segment of the private key;

[0014] The first fragment of the private key is stored in the trusted authority, and the second fragment of the private key is stored in the client.

[0015] In another embodiment of the method provided by the present invention, the first fragment of the private key is stored in the

The trusted institution storing the second fragment of the private key on the client includes:

[0016] The first fragments of different private keys are stored in different trusted institutions, and the second fragments of different private keys are stored in different hardware areas of the client. Among them, the signature levels authorized by different trusted institutions different.

[0017] In another embodiment of the method provided by the present invention, the determining the signature level of the transaction data according to the relationship between the transaction amount in the transaction data and the first threshold includes:

[0018] When the transaction amount is greater than or equal to the first threshold, determining that the signature level of the transaction data is the first level;

[0019] When the transaction amount is less than the first threshold, it is determined that the signature level of the transaction data is the second level.

[0020] In another embodiment of the method provided by the present invention, the determining the signature level of the transaction data according to the relationship between the transaction amount in the transaction data and the first threshold value further includes:

[0021] When the transaction amount is less than a second threshold, it is determined that the signature level of the transaction data is a third level, and the second threshold is less than the first threshold.

[0022] In another embodiment of the method provided by the present invention, the determining a signature authority based on the signature level includes:

[0023] When it is determined that the signature level is the first level, it is determined that there are at least two signature agencies authorized to authorize the signature level;

[0024] When it is determined that the signature level is the second level or the third level, it is determined that the signature authority that authorizes the signature level includes one.

[0025] On the other hand, this embodiment also provides a signature device based on secure multi-party computing, including:

[0026] A transaction data acquisition module for acquiring transaction data, and generating transaction hashes using preset rules for the transaction data;

[0027] The signature level determination module is used to determine the signature level of the transaction data according to the relationship between the transaction amount in the transaction data and the first threshold;

[0028] The signature authority determination module is configured to determine a signature authority based on the signature level, the signature authority being a trusted authority that signs the transaction data;

[0029] The signature authentication module is configured to perform signature authentication based on secure multi-party calculation on the transaction hash based on the private key fragments saved by the determined signature authority and the private key fragments saved by the client, wherein the The trusted authority and the client respectively store private key fragments, and the private key fragments are composed of partial sub-private keys generated based on splitting the asymmetric key.

[0030] In another embodiment of the device provided by the present invention, the trusted organization and the client separately store private key fragments, including:

[0031] The key generation module is used to generate at least two pairs of asymmetric keys during the registration process;

[0032] The fragment obtaining module is used to split the private key in the asymmetric key to obtain the first fragment of the private key and the second fragment of the private key;

[0033] The fragment saving module is configured to save the first fragment of the private key in the trusted authority, and save the second fragment of the private key in the client.

[0034] In another embodiment of the apparatus provided by the present invention, the signature level determination module includes:

[0035] The first determining unit is configured to determine the number of transactions when the transaction amount is greater than or equal to the first threshold

The signature level of the data is the first level;

[0036] The second determining unit is configured to determine that the signature level of the transaction data is the second level when the transaction amount is less than the first threshold.

[0037] In another embodiment of the device provided by the present invention, the signature level determining module further includes: [0038] A third determining unit configured to determine when the transaction amount is less than a second threshold The signature level of the transaction data is the third level, and the second threshold is less than the first threshold.

[0039] On the other hand, this embodiment provides a signature device based on secure multi-party computing, including a processor and a memory for storing processor-executable instructions. When the instructions are executed by the processor, the implementation includes the following steps :

[0040] Obtain transaction data, and generate a transaction hash using preset rules for the transaction data;

[0041] Determine the signature level of the transaction data according to the relationship between the transaction amount in the transaction data and the first threshold;

[0042] Based on the signature level, a signature authority is determined, and the signature authority is a trusted authority that signs the transaction data;

[0043] Based on the private key fragments saved by the determined signature authority and the private key fragments saved by the client, signature verification based on secure multi-party calculation is performed on the transaction hash, wherein the trusted authority and the The client separately saves private key fragments, and the private key fragments are composed of partial sub-private keys generated based on splitting the asymmetric key.

[0044] On the other hand, this embodiment provides a signature system based on secure multi-party computing, including at least one processor and a memory storing computer-executable instructions. The processor implements any of the foregoing embodiments when the instructions are executed. The steps of the method.

[0045] The present embodiment provides a signature method, device, and system based on secure multi-party calculations. At least two pairs of asymmetric keys are generated when applying for registration, and then the private key in the key is segmented and saved to multiple Trusted third-party institutions and user clients, when actually conducting transactions, compare the transaction amount with a preset threshold to determine the signature level of the transaction and the signing institution, and then use the private key saved by the signing institution to split and client The private key fragments stored on the terminal perform signature verification based on secure multi-party calculations on transaction data, realizing dynamic multi-key simultaneous signing. In this way, since the possibility of multiple third-party organizations being compromised at the same time is very low, the implementation provided by this method can effectively solve the security risks of loss or theft of private keys while realizing dynamic multi-key signatures. Improve transaction security.

Description of the drawings

[0046] In order to more clearly describe the technical solutions in this embodiment or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiment or the prior art. Obviously, the appendix in the following description The drawings are only some of the embodiments described in this document. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.

[0047] FIG. 1 is a schematic flowchart of an embodiment of a signature method based on secure multi-party computing provided by the present invention;

[0048] FIG. 2 is a schematic flow diagram of an embodiment of the key processing in the registration application process provided by the present; [0049] FIG. 3 is an implementation of the private key sharding party that provides a private key for small signatures based on secure multi-party calculations provided by the present invention Example structure diagram;

[0050] FIG. 4 is a schematic flow diagram of an embodiment of a small-amount signature authentication based on secure multi-party computing provided by the present invention;

[0051] FIG. 5 is a schematic structural diagram of an embodiment in which a private key sharding party needs to be provided for a medium signature based on a secure multi-party calculation provided by the present invention;

[0052] FIG. 6 is a schematic structural diagram of an embodiment provided by the present invention in which a private key sharding party needs to be provided for a large-amount signature based on secure multi-party calculation;

[0053] FIG. 7 is a schematic diagram of a module structure of an embodiment of a signature device based on secure multi-party computing provided by the present invention;

[0054] FIG. 8 is a schematic diagram of the module structure of an embodiment of a signature system based on secure multi-party computing provided by the present invention.

Detailed ways

[0055] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in this embodiment will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the description The embodiments are only a part of the embodiments in this, but not all of the embodiments. Based on one or more embodiments in the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative work shall fall within the protection scope of the present embodiment.

[0056] At present, in digital asset management and asset transactions, the dynamic signature method based on secure multi-party computing is to divide the private key in the asymmetric key into two pieces, one piece for the institution and one piece for the user personally. Only the institution and the individual share the private key. Signing is required to complete the transaction process. Although this solution can largely alleviate the security problem of a single key being lost and stolen, in an extreme case: when the keys of individuals and institutions are both stolen, the security of assets cannot be guaranteed. It can be seen that the existing widely used asymmetric key scheme still has great security problems.

[0057] Correspondingly, in one or more embodiments of the present invention, at least two pairs of asymmetric keys are generated during the registration application, and then the private key in the key is segmented and saved to multiple trusted third-party institutions And in the user client, when the transaction is actually performed, the transaction amount is compared with the preset threshold to determine the signature level of the transaction and the signature authority, and then use the private key fragments saved by the signature authority and the private key saved by the client Fragmentation performs signature verification based on secure multi-party calculations on transaction data, realizing dynamic multi-key simultaneous signatures. In this way, since the possibility of multiple third-party institutions being compromised at the same time is very low, the implementation provided by this method can effectively solve the security risks of loss or theft of private keys while realizing dynamic multi-key signatures. Improve transaction security.

[0058] The following takes a specific application scenario as an example to describe this embodiment. Specifically, FIG. 1 is a schematic flowchart of an embodiment of a signature method based on secure multi-party computing provided by the present invention. Although this specification 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 after partial combination based on conventional or no creative labor. Or modular unit. 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 this embodiment or the drawings. When the described method or module structure is applied to an actual device, server or terminal product, it can be executed sequentially or in parallel according to the method or module structure shown in the embodiments or drawings (for example, parallel processor or multi-threaded processing). Environment, even including the implementation environment of distributed processing and server clusters).

[0059] Of course, the description of the following embodiments does not limit other technical solutions that can be extended based on the present invention.

system.

[0060] A specific embodiment is shown in FIG. 1. In an embodiment of a signature method based on secure multi-party computing provided by the present invention, the method may include:

[0061] S1: Obtain transaction data, and generate a transaction hash using preset rules for the transaction data.

[0062] Transaction data is data information generated when a transaction party conducts a transaction, and may at least include a transaction amount. For example, it may be online shopping or offline bill payment, etc., both of which include at least the transaction amount. The preset rule is the algorithm that converts transaction data into transaction hash, which can be MD5 (Message-Digest Algorithm 5), SHA (Secure Hash Algorithm), etc., or other algorithms. There is no restriction on this. Hash, or HASH, is called hash in mathematics. It is like a fingerprint of data. The form of expression can be expressed by a string of letters, numbers or other symbols. Transaction HASH is a character segment that can mark transaction data, and in general, it is a transaction certificate.

[0063] In this embodiment, by acquiring transaction data, the transaction data is generated using a preset algorithm to generate a transaction hash, that is, the transaction data is converted into a character string marking the transaction data, which provides a basis for further signature verification.

[0064] In this embodiment, the trusted organization and the client separately store private key fragments, including: generating at least two pairs of asymmetric keys during the registration process, and storing the asymmetric keys in the Split the private key to obtain the first shard of the private key and the second shard of the private key, save the first shard of the private key in the trusted authority, and save the second shard of the private key in The client. Wherein, storing the first fragment of the private key in the trusted institution and storing the second fragment of the private key in the client includes: storing the first fragment of different private keys in different In the trust organization, different second fragments of the private key are stored in different hardware areas of the client, where the signature levels authorized by different trusted organizations may be different.

[0065] Specifically, taking the generation of two pairs of keys as an example, in the process of applying for registration, two pairs of asymmetric keys A and B are generated, and at the same time, the private keys SKA and SKB of the two pairs of keys are split, respectively. Get SKA 1 and SKA2, SKB1 and SKB2, and then keep a part of the split private key (SKA1, SKB1) in the secure storage area inside the trusted organization, and distribute the other part (SKA2, SKB2) to users safely, The user puts two pieces of private keys into different security areas of the client, such as the SIM (Subscriber Identity Module) card of the mobile phone and the TEE (Trust Execution Environment) of the CPU of the mobile phone. As shown in Fig. 2, Fig. 2 is a schematic flowchart of an embodiment of the key processing in the registration application process provided by the present invention. Among them, the arrow of private key A segment 1 pointing to trusted organization 1 means that private key A segment 1 is saved to trusted organization 1; similarly, the arrow of private key B segment 1 pointing to trusted organization 2 means that the private key B segment 1 is saved to trusted institution 2. The arrow pointing to the SIM of the private key A segment 2 indicates that the private key A segment 2 is stored in the secure area of the SIM card on the mobile device (mobile phone); in the same way, the private key B segment 2 is secured by the TEE in the mobile device (mobile phone) CPU Area to save. Trusted institution 1 points to The SIM card indicates that the trusted institution 1 interacts with the SIM card; in the same way, the trusted institution 2 points to the TEE, which indicates that the trusted institution 2 interacts with the TEE. In this way, by storing the two private keys in different hardware security areas, it is more difficult for hackers to crack two different security hardware at the same time, which can increase security.

[0066] It should be noted that the application registration process can be completed by the user interacting with trusted institutions 1 and 2 through the mobile phone wallet APP proxy. Among them, wallets are generally developed by third parties. In some embodiments, the wallet may be provided by a transaction institution, or may be provided by one of the trusted institutions. Generally, the transaction function is also integrated in the wallet function to facilitate users to implement transactions.

[0067] In addition, the above-mentioned two pairs of asymmetric keys generated during the registration application process are merely illustrative.

Bright. In specific implementation, more than two pairs of asymmetric keys can be generated during the registration process mentioned above. The processing method is similar to the processing method of generating two pairs of keys. For the specific implementation method, please refer to the method of generating two pairs of keys. The description of the processing embodiment will not be repeated here.

[0068] Further, when subsequent transaction data processing is performed in response to user instructions, the trusted institution and the user client are required to provide the private key fragments that they hold together in order to perform specific transaction data processing. For example, it is necessary to use the private key shards kept by two trusted institutions and the private key shards kept by the client at the same time to call the fund data in the user's account and complete the transaction. Since the possibility of two third-party trusted institutions being compromised at the same time is very low, by introducing two trusted third-party institutions at the same time, even if the third party steals the private key fragments kept by a trusted institution and the client. , It is also impossible to call the user's account, which can greatly improve the security of the user's transaction data processing.

[0069] The foregoing client can be specifically understood as a client device that stores user private key fragments. For example, it can be a mobile phone or tablet that was previously used by the user or previously bound to the user's account. The above-mentioned trusted organization can be understood as a system that stores the user's private key fragments. For example, it may be a banking system or management system that was previously used by the user or previously bound to the user's account. Of course, it should be noted that the clients and trusted institutions listed above are only schematic illustrations. During specific implementation, the aforementioned client may also be other types of electronic devices, or software programs running in the aforementioned electronic devices, etc., and the aforementioned trusted institution may also be other transaction systems. There are no restrictions on the specific forms and types of clients and trusted institutions.

[0070] In addition, in this embodiment, when multiple pairs of asymmetric keys are generated in the registration application process, multiple trusted institutions can be introduced, and when the client saves multiple private key fragments, it can be processed through software. It is stored in different security areas; for different trusted institutions, different signature levels can be granted according to the actual situation. For example, in some embodiments, two trusted institutions are introduced. Trusted institution 1 can be preset to authenticate transactions with a smaller amount and trusted institution 2 to authenticate signatures with a larger amount. However, two trusted institutions are required for huge transactions. At the same time signature authentication. In other embodiments, two trusted institutions are introduced, and the two trusted institutions can be set to have the same signature level. In the case of small transactions, one trusted institution is randomly selected for authentication, and two trusted institutions are required when the transaction amount is large. At the same time, the trusted organization signs and authenticates.

[0071] S2: Determine the signature level of the transaction data according to the relationship between the transaction amount in the transaction data and the first threshold.

[0072] The first threshold may be preset according to actual transactions, or may be preset according to customer needs. The signature level can be understood as the security level of the transaction amount.

[0073] In this embodiment, the signature level can be divided into two levels according to actual scenarios, that is, when the transaction amount is greater than or equal to the first threshold, the signature level of the transaction data is determined to be the first level, and when the transaction amount is greater than or equal to the first threshold, the signature level of the transaction data is determined to be the first level. When the transaction amount is less than the first threshold, it is determined that the signature level of the transaction data is the second level. Specifically, a limit can be set in advance. When the transaction limit is greater than or equal to the limit, it can be determined that the signature level of the transaction belongs to the first level, that is, a large amount signature; when the transaction limit is less than the limit, the signature level of the transaction can be determined Belongs to the second level, that is, small signatures. For example, the user presets the banks transaction limit as 1000. When the transaction amount exceeds 1000, it is a large-value signature and requires multiple parties to perform signature verification; when the transaction amount is less than 1000, it is a small-value signature and only one institution is required. The signature verification is sufficient.

[0074] In another embodiment, the signature level can be divided into three levels according to actual scenarios, that is, when the transaction amount is greater than or equal to the first threshold, it is determined that the signature level of the transaction data is the first level, when When the transaction amount is less than the first threshold, the signature level of the transaction data is determined to be the second level, and when the transaction amount is less than the second threshold, the signature level of the transaction data is determined to be the third level, so The second threshold is less than the first threshold.

Specifically, two quotas can be set in advance (the first quota is greater than the second quota). When the transaction quota is greater than or equal to the first quota, it can be determined that the signature level of the transaction belongs to the first level, that is, a large-value signature; when the transaction quota is greater than When it is equal to the second amount and less than the first amount, it can be determined that the signature level of the transaction belongs to the second level, that is, the middle amount signature; when the transaction amount is less than the second amount, it can be determined that the signature level of the transaction belongs to the third level, that is Sign a small amount. For example, the user presets the banks transaction quotas of 1000 and 500. When a transaction amount exceeds 1000, it is a large-value signature and requires multiple parties to perform signature verification; when the transaction amount is greater than or equal to 500 and less than 1000, it belongs to A medium-value signature requires an institution to perform signature verification; when the transaction amount is less than 500, it is a small-value signature and requires an institution to perform signature verification. In this way, when large-value transactions are carried out, even if the key fragments of individuals and an organization are stolen, the security of assets can be effectively protected.

[0075] It should be noted that the transaction quota corresponding to the first level is greater than the transaction quota corresponding to the second level, and the transaction quota corresponding to the second level is greater than the transaction quota corresponding to the third level. In addition, the above-mentioned signature levels of two or three levels are merely illustrative. In specific implementation, the above-mentioned signature levels can also be divided into other levels according to actual needs, which is not limited here.

[0076] S3: Determine a signature authority based on the signature level, where the signature authority is a trusted authority that signs the transaction data.

[0077] Since the signature agency is a trusted agency that signs the transaction data, and the signature levels authorized by different trusted agencies can be different, so when the transaction amount is determined according to the relationship between the transaction amount and the first threshold in the transaction data For the signature level of transaction data, the signature authority required for signature verification of the current transaction can be determined according to the signature levels authorized by different trusted institutions.

[0078] In the following embodiment, when the signature level is divided into two levels, and the signature level is determined to be the first level, it can be determined that the signature authority authorized by the signature level includes at least two; when the signature is determined When the level is the second level, it can be determined that the signature authority that authorizes the signature level includes one. Specifically, in the transaction process, assuming that the signature level is preset to two levels, when the signature level is a large-value signature, at least two trusted institutions authorized to perform large-value signatures are required to perform signature verification at the same time; In the case of small-value signatures, only a trusted organization authorized to perform small-value signatures can perform signature verification.

[0079] In another embodiment of the present invention, when the signature level is divided into three levels, and the signature level is determined to be the first level, it is determined that at least two signature agencies authorizing the signature level are included; when the signature is determined When the level is the second level, it is determined that the signature level is authorized to include one signature authority; when the signature level is determined to be the third level, it is determined that the signature level is authorized to include one signature authority. Specifically, assuming that the signature level is preset to three levels, when the signature level is a large-value signature, at least two trusted institutions authorized to perform large-value signatures are required to perform signature authentication; when the signature level is a medium-value signature, only A trusted institution authorized to perform medium-value signatures can perform signature verification; when the signature level is a small-value signature, only a trusted institution authorized to perform small-value signatures can perform signature verification. In this way, by determining the signature level according to the transaction amount during the transaction, and then using the corresponding relationship between the signature level and the signature institution to determine the final signature institution required, the security of the asset can be effectively guaranteed.

[0080] It should be noted that the signature levels authorized by different trusted institutions can be different or the same, which is not limited here. For example, in some embodiments, two trusted institutions are introduced. Trusted institution 1 can be preset to authenticate transactions with a smaller amount and trusted institution 2 to authenticate signatures with a larger amount. However, two trusted institutions are required for huge transactions. At the same time signature authentication. In other embodiments, two trusted institutions are introduced, and the two trusted institutions can be set to have the same signature level. In the case of small transactions, one trusted institution is randomly selected for authentication. When the transaction amount is large, two are required Trusted institutions at the same time

Signature certification.

[0081] S4: Based on the private key fragments saved by the determined signature authority and the private key fragments saved by the client, perform signature authentication based on secure multi-party computation on the transaction hash, wherein the trusted authority and The clients respectively store private key fragments, and the private key fragments are composed of partial sub-private keys generated based on splitting the asymmetric key.

[0082] Secure Multi-Party Computation (MPC) is a collaborative computing problem that solves privacy protection between a group of untrusted parties. It can be abstractly understood as: multiple parties holding their own private data , Execute a function together (for example, calculate the maximum value), and obtain the calculation result, but in the process, each party involved will not leak their own data. Signature verification can also be understood as transaction signature. Transaction signature is to digitally sign the transaction, that is, digitally sign the transaction data packet (block) composed of transaction information, including the transaction information such as the trader, amount, time, etc., generally initiated by the transaction (Usually the transferor of the asset) signature, and digital signature (also known as public key digital signature, electronic signature, etc.) is a kind of ordinary physical signature similar to written on paper, but uses technology in the field of public key encryption Implementation, a method used to identify digital information. In addition, digital signatures need to use public and private keys, the private key is used for signature, and the public key is used for verification. In general, the algorithms that can be used for signatures include RSA (Rivest-Shamir-Adleman, an asymmetric encryption algorithm), DSA (Digital Signature Algorithm, digital signature algorithm), ECDSA (Elliptic Curve Digital Signature Algorithm, elliptic curve digital signature encryption algorithm), but ECDSA is mainly used in the blockchain, and other signature algorithms can also be used for signing, which is not limited.

[0083] In this embodiment, since at least two pairs of asymmetric keys are generated during the registration process, the private key in the asymmetric key is then divided to obtain the first fragment of the private key and the second fragment of the private key. Two fragments, storing the first fragment of the private key in a trusted institution, and storing the second fragment of the private key in the client. Among them, the first shards of different private keys are stored in different trusted institutions, and the second shards of different private keys are stored in different hardware areas of the client. Therefore, according to the relationship between the transaction amount and the first threshold in the transaction data , After determining the signature level of the transaction data, and determining the final signature authority required according to the corresponding relationship between the signature level and the signature authority, it can be based on the private key shards stored by the determined signature authority and the private key shards saved by the client , Perform signature verification based on secure multi-party calculation on the transaction hash.

[0084] Specifically, when the signature level is preset to three levels, and two different trusted institutions (institution 1, institution 2) have different authorization levels, it is assumed that institution 1 is preset to perform small-value signature authentication, Institution 2 performs medium-value signature authentication. Large-value transactions require two institutions to sign and authenticate at the same time. When the current transaction amount belongs to small-value signatures, the required signature agency is determined to be institution 1, and the private key saved by institution 1 is used. Sharding and the private key saved by the client are sharded, and signature verification based on secure multi-party calculation is performed on the transaction hash; when the current transaction amount belongs to a medium signature, the required signature agency is determined to be agency 2, then use The private key shards saved by organization 2 and the private key shards saved by the client are used to perform signature verification based on secure multi-party calculation on the transaction hash; when the current transaction amount belongs to a large-value signature, the required signature is determined If the institutions are institution 1 and institution 2, use the private key shards saved by institution 1, the private key shards saved by institution 2, and the private key shards saved by the client, and the transaction hash is based on secure multi-party Calculated signature authentication. Wherein, the private key segment is composed of partial sub-private keys generated based on segmenting the asymmetric key.

[0085] Further, assuming that the signature level is preset to three levels: small signature, medium signature, and large signature, institution 1 performs small signature authentication, and institution 2 performs medium signature authentication. Large transactions require two institutions Sign authentication at the same time, and generate two pairs of asymmetric keys A and B during the registration process, and split the private keys in the two pairs of keys to obtain private key A fragment 1 and private key A fragment 2 respectively , Private key B fragment 1 and private key B fragment 2, and then save the split private key A fragment 1 in organization 1, private key B fragment 1 in organization 2, and private key A Piece 2 and private key B piece 2 are stored on the user's mobile phone, and the organization that chooses to sign the transaction may be different depending on the transaction amount. For example, as shown in Figure 3, Figure 4, Figure 5, Figure 6, Figure 3

It is a schematic diagram of the structure of an embodiment of the small-amount signature based on secure multi-party computing that needs to provide a private key sharding party. FIG. 4 is a schematic flow diagram of an embodiment of the provided small-amount signature authentication based on secure multi-party computing. Figure 5 is a schematic diagram of an embodiment of the provided private key sharding party for a medium signature based on secure multi-party computing. Figure 6 is one of the private key sharding parties provided for a large signature based on secure multi-party computing. Schematic diagram of the structure of the embodiment. Among them, in Figure 4, the function Sign = F (A1, A2) can represent the private key A segment 1 (A1) saved by the organization 1 and the private key A segment 2 (A2) saved by the user's mobile phone as the function F Input and get the output result Sign process, that is, each participant (institution 1 and user's mobile phone) has their own private data (A1, A2). Without leaking their private data, they can calculate the public function ( The result of F), and when the entire function calculation is completed, each participant only knows the calculation result (Sign).

[0086] In addition, in the above-mentioned embodiment, it is also possible to set two institutions to have the same signature level. When signing a small amount and signing a medium amount, one institution can be randomly selected for signature verification. When signing a large amount, the two institutions At the same time signature authentication.

[0087] It should be noted that the implementation process of the medium signature and the large signature can refer to the flowchart in FIG. 4, which will not be repeated here. For the embodiment where the signature level is preset to other levels, a method similar to the above or other methods can be used to implement the signature, which is not limited. This article only takes two pairs of asymmetric keys generated during the registration application, and there are two corresponding institutions as an example, which is just a schematic illustration. In specific implementation, multiple pairs of asymmetric keys and multiple institutions can be used, and this is not limited.

[0088] The present embodiment provides a signature method based on secure multi-party computation, which generates at least two pairs of asymmetric keys during registration application, and then splits the private key in the key and saves it to multiple trusted third parties In the different hardware areas of the institution and the user client, when the transaction is actually performed, the transaction amount is compared with the preset threshold to determine the signature level of the transaction and the signature institution, and then use the private key saved by the signature institution to slice and client The saved private key fragments perform signature verification based on secure multi-party calculations on transaction data, realizing dynamic multi-key simultaneous signing. In this way, since the possibility of multiple third-party organizations being compromised at the same time is very low, the implementation provided by this method can effectively solve the security risks of loss or theft of private keys while realizing dynamic multi-key signatures. Improve transaction security.

[0089] Based on the above-mentioned signature method based on secure multi-party computing, one or more embodiments of the present invention also provide a signature device based on secure multi-party computing. The described devices may include systems (including distributed systems), software (applications), modules, components, servers, clients, etc., which use the method described in this embodiment, combined with necessary implementation hardware devices. Based on the same innovative concept, the devices in one or more embodiments provided in this embodiment are as described in the following embodiments. Since the implementation scheme of the device to solve the problem is similar to the method, the implementation of the specific device in this embodiment can refer to the implementation of the foregoing method, and the repetition will not be repeated. As used below, the term "unit" or "module" can be a combination of software and/or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented by software, implementation by hardware or a combination of software and hardware is also possible and conceived.

[0090] Specifically, FIG. 7 is a schematic diagram of the module structure of an embodiment of a signature device based on secure multi-party computing provided by the present invention. As shown in FIG. 7, a signature device based on secure multi-party computing provided by the present invention may include : Transaction data acquisition module 121, signature level determination module 122, signature authority determination module 123, signature verification module 124. Wherein, the transaction data obtaining module 121 may be used to obtain transaction data, and generate a transaction hash using preset rules for the transaction data;

[0091] The signature level determining module 122 may be used to determine the signature level of the transaction data according to the relationship between the transaction amount in the transaction data and the first threshold;

[0092] The signature authority determination module 123 may be used to determine a signature authority based on the signature level, where the signature authority is a trusted authority that signs the transaction data;

[0093] The signature verification module 124 may be used to perform signature verification based on secure multi-party calculation on the transaction hash based on the private key fragments saved by the determined signature authority and the private key fragments saved by the client, where: The trusted organization and the client respectively store private key fragments, and the private key fragments are composed of partial sub-private keys generated based on splitting an asymmetric key.

[0094] In another embodiment of the apparatus, that the trusted organization and the client separately store private key fragments, which may include:

[0095] The key generation module can be used to generate at least two pairs of asymmetric keys during the registration process;

[0096] The fragment obtaining module can be used to split the private key in the asymmetric key to obtain the first fragment of the private key and the second fragment of the private key;

[0097] The fragment saving module may be used to save the first fragment of the private key in the trusted authority, and save the second fragment of the private key in the client.

[0098] In another embodiment of the apparatus, the signature level determining module 122 may include:

[0099] The first determining unit may be configured to determine that the signature level of the transaction data is the first level when the transaction amount is greater than or equal to the first threshold;

[0100] The second determining unit may be used to determine that the signature level of the transaction data is the second level when the transaction amount is less than the first threshold.

[0101] In another embodiment of the apparatus, the signature level determining module 122 may further include:

[0102] The third determining unit may be configured to determine that the signature level of the transaction data is a third level when the transaction amount is less than a second threshold, and the second threshold is less than the first threshold.

[0103] It should be noted that the above-mentioned device may also include other implementation manners according to the description of the method embodiment, and the specific implementation manner may refer to the description of the related method embodiment, which is not repeated here.

[0104] This particular embodiment has been described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can 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 in order to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0105] The method described in the foregoing embodiment provided by the present invention can implement business logic through a computer program and record it on a storage medium, and the storage medium can be read and executed by a computer to achieve the effects of the solution described in this embodiment. Therefore, the present invention also provides a signature device based on secure multi-party computing, including a processor and a memory for storing processor-executable instructions. When the instructions are executed by the processor, the implementation includes the following steps: [0106] Obtaining a transaction Data, using the transaction data to generate a transaction hash using preset rules;

[0107] Determine the signature level of the transaction data according to the relationship between the transaction amount in the transaction data and the first threshold;

[0108] Based on the signature level, determine a signature authority, which is a trusted authority that signs the transaction data;

[0109] Based on the private key fragments saved by the determined signature authority and the private key fragments saved by the client, signature verification based on secure multi-party calculation is performed on the transaction hash, wherein the trusted authority and the The client holds the private key separately

Fragmentation, the private key fragmentation is composed of partial sub-private keys generated based on segmentation of the asymmetric key.

[0110] The storage medium may include a physical device for storing information, which is usually digitized and then stored in an electric, magnetic, or optical medium. The storage medium may include: devices that use electric energy to store information, such as various types of memory, such as RAM, ROM, etc.; devices that use magnetic energy to store information, such as hard disks, floppy disks, magnetic tapes, magnetic core memories, magnetic bubble memories, U disk; a device that uses optical means to store information, such as a CD or DVD. Of course, there are other ways of readable storage media, such as quantum memory, graphene memory, and so on.

[0111] It should be noted that the above-mentioned device may also include other implementation manners according to the description of the method embodiment. For specific implementation manners, reference may be made to the description of the related method embodiments, which will not be repeated here.

[0112] The above-mentioned signature method, device, and device based on secure multi-party computing provided by this embodiment can be implemented in a computer by a processor executing corresponding program instructions, such as using the c++ language of the windows operating system on the PC side, linux system implementation, or other implementations such as using android and iOS system programming languages in smart terminals, and quantum computer-based processing logic implementation, etc. The present invention provides an embodiment of a signature system based on secure multi-party computing. FIG. 8 is a schematic diagram of the module structure of an embodiment of a signature system based on secure multi-party computing provided by the present invention. As shown in FIG. A signature system based on secure multi-party computing may include a processor 131 and a memory 132 for storing executable instructions of the processor. The processor 131 and the memory 132 communicate with each other through a bus 133;

[0113] The processor 131 is configured to call the program instructions in the memory 132 to execute the method provided in the above-mentioned secure multi-party calculation-based signature method embodiment, for example, including: obtaining transaction data, and using the transaction data The transaction hash is generated by a preset rule; the signature level of the transaction data is determined according to the relationship between the transaction amount in the transaction data and the first threshold; based on the signature level, a signature authority is determined, and the signature authority is A trusted institution that signs transaction data; based on the private key fragments stored by the determined signature institution and the private key fragments stored by the client, the transaction hash is authenticated based on secure multi-party calculations, wherein the The trusted authority and the client respectively store private key fragments, and the private key fragments are composed of partial sub-private keys generated based on splitting the asymmetric key.

[0114] It should be noted that the above-mentioned system may also include other implementation manners according to the description of the related method embodiments. For specific implementation manners, refer to the description of the method embodiments, which will not be repeated here. The various embodiments in this application 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.

[0115] The present embodiment provides a signature device or device or system based on secure multi-party computing, which generates at least two pairs of asymmetric keys when applying for registration, and then splits and saves the private key in the key to multiple Trusted third-party institutions and user clients, when actually conducting transactions, compare the transaction amount with a preset threshold to determine the signature level of the transaction and the signing institution, and then use the private key saved by the signing institution to split and client The private key fragments stored on the terminal perform signature verification based on secure multi-party calculations on transaction data, realizing dynamic multi-key simultaneous signing. In this way, since the possibility of multiple third-party institutions being compromised at the same time is very low, the implementation provided by this method can effectively solve the security risks of loss or theft of private keys while realizing dynamic multi-key signatures. Improve transaction security.

[0116] This embodiment is not limited to complying with industry communication standards, standard computer data processing and data storage rules, or the situation described in one or more embodiments. Some industry standards or use custom methods

The implementations described in the formulas or examples with slight modifications can also achieve the same, equivalent or similar implementation effects of the above-mentioned examples, or predictable implementation effects after modification. Embodiments obtained by applying these modified or deformed data acquisition, storage, judgment, processing methods, etc., may still fall within the optional implementation scope of this embodiment.

[0117] In the 1990s, the improvement of a technology can be clearly distinguished between hardware improvements (for example, improvements in circuit structures such as diodes, transistors, switches, etc.) or software improvements (improvements in method flow). ). However, with the development of technology, the improvement of many methods and procedures can be regarded as a direct improvement of the hardware circuit structure. Designers almost always get the corresponding hardware circuit structure by programming the improved method flow into the hardware circuit. Therefore, it cannot be said that the improvement of a method flow cannot be realized by the hardware entity module. For example, a Programmable Logic Device (PLD) (such as a Field Programmable Gate Array (FPGA)) is such an integrated circuit whose logic function is determined by the user's programming of the device. It is programmed by the designer to "integrate" a digital system on a PLD without requiring the chip manufacturer to design and manufacture a dedicated integrated circuit chip. Moreover, nowadays, instead of manually making integrated circuit chips, this kind of programming is mostly realized by using "logic compiler" software, which is similar to the software compiler used in program development and writing. The original code must also be written in a specific programming language, which is called hardware description language (Hardware Description Language, HDL), and HDL is not only one, but there are many, such as ABEL (Advanced Boolean Expression Language)>AHDL (Altera Hardware Description Language)>Confluence>CUPL (Cornell University Programming Language)>HDCal>JHDL (Java Hardware Description Language), Lava, Lola, MyHDL, PALASM, RHDL (Ruby Hardware Description Language), etc. The most commonly used at present are VHDL (Very-High-Speed Integrated Circuit Hardware Description Language) and Verilog. It should also be clear to those skilled in the art that just a little bit of logic programming of the method flow in the above-mentioned hardware description languages and programming into an integrated circuit can easily obtain the hardware circuit that implements the logic method flow.

[0118] The controller can be implemented in any suitable manner. For example, the controller can take the form of, for example, a microprocessor or a processor, and a computer storing computer-readable program codes (such as software or firmware) executable by the (micro)processor. In the form of readable media, logic gates, switches, application specific integrated circuits (ASICs), programmable logic controllers and embedded microcontrollers, examples of controllers include but are not limited to the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20 and Silicon Labs C8051F320, the memory controller can also be implemented as part of the memory control logic. Those skilled in the art also know that in addition to implementing the controller in a purely computer-readable program code manner, it is completely possible to program the method steps to make the controller use logic gates, switches, application specific integrated circuits, programmable logic controllers, and embedded logic. The same function can be realized in the form of a microcontroller or the like. Therefore, such a controller can be regarded as a hardware component, and the devices included in it 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.

[0119] The systems, devices, modules, or units illustrated in the foregoing 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.

[0120] Although the present one or more embodiments provide the method operation steps as described in the embodiments or flowcharts,

However, conventional or non-innovative methods may include more or fewer operation steps. The sequence of steps listed in the embodiments is only one way of the execution order of the steps, and does not represent the only execution order. When the actual device or terminal product is executed, it can be executed sequentially or in parallel according to the methods shown in the embodiments or the drawings (for example, in 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. Words such as first and second are used to denote names, but do not denote any specific order.

[0121] For the convenience of description, when describing the above device, the functions are divided into various modules and described separately. Of course, when implementing one or more of these modules, the function of each module can be implemented in the same one or more software and/or hardware, or the 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.

[0122] 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.

[0123] 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 instruction device realizes the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

[0124] 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 that the computer or other programmable equipment The instructions executed above 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.

[0125] In a typical configuration, the computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

[0126] The memory may include non-permanent memory in a computer readable medium, 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.

[0127] Computer-readable media including permanent and non-permanent, removable and non-removable media can be implemented by any method or technology for information storage. 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 cassette, magnetic tape magnetic disk Storage, graphene 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.

[0128] Those skilled in the art should understand that one or more embodiments of the present invention may be provided as a method, a system, or a computer program product. Therefore, the present one or more embodiments may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present one or more embodiments may adopt computer program products 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. form.

[0129] The various embodiments in the present invention 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 this description, descriptions with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean the specific features described in conjunction with the embodiment or example, The structure, material or feature is included in at least one embodiment or example of the present invention. In this context, the schematic representations of the above-mentioned 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 document without conflicting each other.

[0130] The foregoing descriptions are only examples of one or more embodiments of the present invention, and are not intended to limit one or more embodiments of the present specification. For those skilled in the art, various modifications and changes can be made to the one or more embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the scope of the claims.