Certificateless weighted multi-identity cross-domain authentication scheme combined with block chain

Abstract

The invention discloses a certificateless weighted multi-identity cross-domain authentication scheme combined with a block chain, and aims to solve the problem that the existing related technology is difficult to adapt to diversified authentication of a complex Internet of Things environment. According to the method, a certificateless weighted cross-domain authentication scheme is designed by considering the multi-identity characteristics of cross-domain users and the credible weight difference of different identities. According to the scheme, a distributed block chain structure is adopted, and the non-tampering performance and the synchronization reliability of parameters are guaranteed; through cooperation of a threshold signature algorithm and a certificateless signature algorithm, the overall security of the system is maintained, and the third-party key escrow risk is thoroughly avoided. Besides, the digital signature protocol integrated with the identity weight is designed to realize differential authentication, the user with higher credible weight only needs less part of identity information to complete authentication of the user with low weight, and the efficiency is greatly improved. According to the invention, the security, reliability and flexibility of cross-domain authentication are enhanced, specific scene requirements of the Internet of Things are adapted, and an efficient solution is provided.

Description

Technical Field

[0001] This invention belongs to the fields of network security technology and identity authentication, specifically involving a certificateless, authorized, multi-identity cross-domain authentication method combined with blockchain, applicable to identity authentication scenarios in the Internet of Things, and solving the security and inconsistency problems of identity authentication in such scenarios. Background Technology

[0002] With the rapid development of information technology and internet applications, cross-domain identity authentication has become a core cornerstone for secure collaboration in distributed systems such as the Internet of Things (IoT), the Industrial Internet, and the Internet of Vehicles (IoV). Traditional identity authentication mechanisms are limited to a single trust domain and rely on a centralized management model, making them difficult to adapt to the dynamic needs of multi-domain collaboration. These mechanisms cannot solve the problem of heterogeneity in cross-domain user identities, lack the flexibility of differentiated access control, and also pose a single point of failure risk. As network scale continues to expand, coupled with the increasing demands for security and adaptability in highly sensitive scenarios, two core challenges are gradually emerging: first, how to achieve differentiated identity authentication based on the trust level of cross-domain users; second, how to improve the security and reliability of the authentication mechanism while avoiding the risks of third-party key escrow.

[0003] Blockchain technology, with its decentralized, immutable, transparent and traceable characteristics, is widely regarded as an effective solution to cross-domain trust problems. Many technologies integrate blockchain with cryptographic mechanisms to optimize cross-domain identity authentication schemes. For example, by integrating a lightweight, certificateless signature blockchain-edge computing architecture, the complex certificate management process is effectively simplified; or by simply combining blockchain with certificateless cryptography, the key custody problem in the Internet of Vehicles scenario is solved. However, existing cross-domain authentication schemes combined with blockchain still have significant limitations: (1) Most schemes treat cross-domain users as equal entities, ignoring the differences in trust weight of user identities in different domains, and therefore cannot support differentiated authentication; (2) Few studies consider the actual application scenarios where users hold multiple identities. Traditional schemes rely on single-identity authentication schemes, and once the identity is compromised, they will face serious security risks; (3) Although some schemes use certificateless cryptography to avoid key custody risks, they do not adequately guarantee the security of public key parameters and the flexibility of access control policies.

[0004] Against this backdrop, this invention designs a weighted threshold multi-identity cross-domain authentication scheme combining blockchain technology. The core idea of ​​this scheme lies in its innovative consideration of identity weighting mechanisms and multi-identity threshold signature technology, combining them with certificateless cryptography and blockchain technology to overcome the aforementioned shortcomings of existing solutions. Specifically, this scheme utilizes blockchain technology to achieve distributed storage and sharing of public key parameters, ensuring the immutability and real-time synchronization of the parameters; it employs weighted threshold multi-identity signature technology to achieve differentiated authentication based on user trust levels; and it leverages certificateless cryptography to eliminate the risk of third-party key escrow at the source, providing a practical solution for cross-domain identity authentication needs in real-world scenarios. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a certificateless, authority-based, multi-identity cross-domain authentication scheme that integrates blockchain technology. The scheme achieves differentiated identity authentication between different domains by introducing weights, and enhances signature security by incorporating a multi-identity threshold mechanism.

[0006] This invention is achieved through the following technical solution:

[0007] A certificate-free, authorized, multi-identity cross-domain authentication scheme involves several participating entities, including a key generation center (PKG), a registration center, a blockchain, and users. The scheme primarily includes the following steps:

[0008] (1) System initialization: PKG selects the system parameters and hash function required by the scheme, selects the system master private key and calculates the system master public key;

[0009] (2) User registration: Users submit a set of partial identities to the registration center. The registration center assigns identity weights to each identity based on the user's partial identity characteristics and selects a system threshold.

[0010] (3) Partial key generation: The PKG distributes a partial private key to the user based on the user's identity information;

[0011] (4) Generation of complete public and private keys for all parts of the user's identity: After receiving the partial private key distributed by PKG, the user combines it with their unique identity information to generate the complete private key;

[0012] (5) Signature generation: The signer generates a signature based on its partial identity set and private key, and sends the signature to the verifier, who can use the signature to verify the signer's identity.

[0013] (6) Signature verification: The verifier verifies the validity of the signature by combining the received signature with the signature verification equation.

[0014] Step (1) includes the following steps:

[0015] PKG selects a bilinear mapping: P is Any generator, randomly selects group elements for message signing. as well as , where n represents the number of messages to be signed. And for user U, the group elements used for key calculation. , dimensional vector ,in Indicate user identity The length of the binary sequence. The system selects a weight threshold. Select the system master private key The master public key is The common parameters are: Public parameters are uploaded to the blockchain for storage.

[0016] Step (2) includes the following steps:

[0017] User U obtains their unique identity value from the identity registration center. The identity registration center determines whether the user has already registered. If the user has already registered, the registration fails; otherwise, the registration is completed and made public. The value. Meanwhile, users obtained values ​​from various industry domains. Each part of the identity information is represented as a complete set of identities. .

[0018] Step (3) includes the following steps:

[0019] (a) For a user U, its unique identity value is Its binary sequence is ( User U sends the binary sequence of their identity to the PKG.

[0020] (b) After receiving the PKG, it will randomly select... ,calculate: .

[0021] (c) PKG calculation , It was secretly sent to user U.

[0022] Step (4) includes the following steps:

[0023] (a) User U received Selected Calculate its complete private key User U calculation Then, it requests polynomial invocation permission from PKG. After receiving the request, PKG selects t distinct integers. ,in Construct a polynomial of order t-1: And provide users with calling permissions, allowing users to make local calls. To complete the calculation. For User U randomly selects ,calculate In a finite field Searching for , making ,save p represents a large prime number.

[0024] (b) The user sends a parameter generation request to the PKG, and the user calculates... = , and Representing part of the user's identity and The weight value, and the serial number of all user identities. and Secretly sent to PKG, regarding identity and After receiving the request, PKG randomly selects t distinct integers. Construct a polynomial of degree t-1: .calculate , , PKG will It is sent secretly to the user.

[0025] (c) A user's partial identity and its corresponding identity credibility weight constitute the corresponding weight set. ,in , This represents the total number of partial identities for a user. User U is calculated as follows: .in and Mutual elements, let express The coefficient vector, , It can be represented as: User U's partial identity The private key is: .make: .

[0026] User U Computing ,calculate: The Euclidean algorithm can be used to calculate the expression that satisfies the given conditions. of , thus calculating Save collection Used to generate signatures.

[0027] Step (5) includes the following steps:

[0028] At this point, a user needs to generate a signature to verify their identity, and they select a portion of their identity set. , Participate in signature generation. Receive set. The process of generating the post-signature is as follows:

[0029] (a) The message to be signed is ,in For an integer, representing identity User calculation: .

[0030] (b) User calculation: The final signature is .

[0031] Step (6) includes the following steps:

[0032] For publicly disclosed identity values The signer U1, if the set of identities involved in generating the signature... If the total weight is greater than or equal to the threshold t, then the signature is received by the signature verifier U2. Then, we can verify that the following equation holds true:

[0033]

[0034] If this equation is true, then the authentication is successful.

[0035] Advantages and beneficial effects of the present invention:

[0036] Compared with the prior art, the innovation and beneficial effects of this invention are as follows:

[0037] (1) Weighted cross-domain identity authentication: This invention innovatively takes into account the level difference between different authentication entities. By integrating identity weight into the user's private key for signature generation and verification, the practicality and flexibility of the identity authentication system are greatly improved.

[0038] (2) Multi-identity threshold control: This invention breaks through the single identity limitation of traditional signatures. Considering the problem that users have multiple identities in actual scenarios, it uses multiple identities combined with thresholds to control the validity of signatures. The signer needs to meet the requirement that the total weight of the set of identities participating in the signature is greater than or equal to the threshold specified by the system in order to generate a valid signature, thereby improving the security of the scheme and its ability to resist collusion attacks.

[0039] (3) Certificate-free Blockchain Architecture: This invention adopts a certificate-free architecture, which fundamentally solves the complexity of certificate management in traditional certificate-based signatures, while avoiding the security risks associated with third-party key escrow. In addition, the solution combines blockchain technology to ensure the secure access to relevant parameters and keys, thereby improving the overall security of the solution. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the system model of the present invention;

[0041] Figure 2 This is a basic flowchart of the identity authentication process of the present invention. Detailed Implementation

[0042] The technical solutions in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following embodiments.

[0043] like Figure 1 As shown, a certificateless, authorized multi-identity cross-domain authentication scheme combining blockchain involves four participating entities: a key generation center (PKG), a blockchain, a registration center, and users. The specific implementation is as follows:

[0044] (1) System initialization

[0045] PKG (Private Key Generator) selects a bilinear mapping: P is Any generator, randomly selects group elements for message signing. as well as , where n represents the number of messages to be signed. And for user U, the group elements used for key calculation. , dimensional vector ,in Indicate user identity The length of the binary sequence. The system selects a weight threshold. Where t must satisfy the following conditions: for a group of users (which includes users from various domains with different weights), the trusted weight value of each part of each user's identity is less than t, and the sum of the trusted weights of all identities is greater than or equal to t. Select the system master private key. The master public key is The common parameters are: Public parameters are uploaded to the blockchain for storage.

[0046] (2) User registration

[0047] User U obtains their unique identity value from the identity registration center. The identity registration center determines whether the user has already registered. If the user has already registered, the registration fails; otherwise, the registration is completed and made public. The value. Meanwhile, users obtained values ​​from various industry domains. Each part of the identity information is represented as a complete set of identities. .

[0048] (3) Partial key generation

[0049] For a user U, its unique identity value is Its binary sequence is ( User U sends the binary sequence of their identity to the PKG. Upon receiving it, the PKG randomly selects... ,calculate:

[0050]

[0051] calculate PKG will It was secretly sent to user U.

[0052] (4) Complete key generation and distribution

[0053] User U received Selected Calculate its complete private key User U calculation

[0054]

[0055] Then, it requests polynomial invocation permission from PKG. After receiving the request, PKG selects t distinct integers. ,in Construct a polynomial of order t-1:

[0056]

[0057] And provide users with calling permissions, allowing users to make local calls. To complete the calculation. For User U randomly selects ,calculate In a finite field Searching for , making ,save p represents a large prime number.

[0058] At the same time, the user sends a parameter generation request to PKG, and the user calculates... = , and Representing part of the user's identity and The weight value, and the serial number of all user identities. and Secretly sent to PKG, regarding identity and After receiving the request, PKG randomly selects t distinct integers. Construct a polynomial of degree t-1:

[0059]

[0060] calculate , , PKG will It is sent secretly to the user.

[0061] A user's partial identity and its corresponding identity credibility weight constitute a weight set. ,in , This represents the total number of partial identities for a user.

[0062] User U calculation:

[0063]

[0064] in and Mutual elements, let express The coefficient vector, , It can be represented as:

[0065]

[0066] User U's partial identity The private key is:

[0067]

[0068] make:

[0069]

[0070] calculate ,calculate:

[0071]

[0072] The Euclidean algorithm can be used to calculate the satisfying formula. of , thus calculating Save collection Used to generate signatures.

[0073] (5) Threshold signature generation

[0074] At this point, a user needs to generate a signature to verify their identity, utilizing all the partial identity sets they possess. , Participate in signature generation. Receive set. The process of generating the post-signature is as follows:

[0075] (5.1) Partial signature generation

[0076] The message to be signed is ,in For an integer, representing identity User calculation:

[0077]

[0078] (5.2) Signature synthesis

[0079] User calculation:

[0080]

[0081]

[0082] The final signature is During the signature generation process, if the total weight of the individual identities of the users participating in the signature generation is greater than or equal to a threshold, then the signature is valid; otherwise, a valid signature cannot be generated.

[0083] (6) Signature verification

[0084] For publicly disclosed identity values The signer U1, if the set of identities involved in generating the signature... If the total weight is greater than or equal to the threshold t, then the signature is received by the signature verifier U2. Then, we can verify that the following equation holds true:

[0085]

[0086] If this equation holds true, authentication is successful. For users U1 and U2 from different domains, if the partial identity trust weight of U1 is greater than that of user U2, then U1 only needs to generate a signature using a smaller portion of its identity, and its signature is valid, allowing it to prove its identity to user U2, who has a lower trust weight. This implements a bidirectional interactive identity authentication process when the trust weights of the two parties are different. Furthermore, signatures that do not meet the weight threshold will fail verification.

[0087] The above describes the basic principles, technical solutions, and beneficial effects of this invention. The above embodiments are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Those skilled in the art, after reading this invention, can make equivalent substitutions or improvements without departing from the core technical concept of this invention, and all such equivalent substitutions and improvements should fall within the scope of protection defined by the claims of this invention. The scope of protection of this invention is determined by the appended claims.

Claims

1. A certificateless, authorized, multi-identity cross-domain authentication scheme combining blockchain, characterized in that, It involves four entities: the Key Generation Center (PKG), the Registration Center, the Blockchain, and the users who need to complete authentication. The main steps include: (1) System initialization: PKG selects the system parameters and hash function required by the scheme, selects the system master private key and calculates the system master public key; (2) User registration: Users submit a set of partial identities to the registration center. The registration center assigns identity weights to each identity based on the user's partial identity characteristics and selects a system threshold. (3) Partial key generation: The PKG distributes a partial private key to the user based on the user's identity information; (4) Generation of complete public and private keys for all parts of the user's identity: After receiving the partial private key distributed by PKG, the user combines it with their unique identity information to generate the complete private key; (5) Signature generation: The signer generates a signature based on its partial identity set and private key, and sends the signature to the verifier, who can use the signature to verify the signer's identity. (6) Signature verification: The verifier verifies the validity of the signature by combining the received signature with the signature verification equation.

2. The certificateless, authorized multi-identity cross-domain authentication scheme combining blockchain as described in claim 1, characterized in that, Step (1) includes the following steps: PKG selects a bilinear mapping: P is Any generator, randomly selects group elements for message signing. as well as , where n represents the number of messages to be signed. And for user U, the group elements used for key calculation. , dimensional vector ,in Indicate user identity The length of the binary sequence. The system selects a weight threshold. Select the system master private key The master public key is A set of public parameters is then constructed and uploaded to the blockchain for storage.

3. The certificateless, authorized multi-identity cross-domain authentication scheme combining blockchain as described in claim 1, characterized in that, Step (2) includes the following steps: User U obtains their unique identity value from the identity registration center. The identity registration center determines whether the user has already registered. If the user has already registered, the registration fails; otherwise, the registration is completed and made public. The value. Meanwhile, users obtained values ​​from various industry domains. Each part of the identity information is represented as a complete set of identities. .

4. The certificateless, authorized multi-identity cross-domain authentication scheme combining blockchain as described in claim 1, characterized in that, Step (3) includes the following steps: (a) For a user U, its unique identity value is Its binary sequence is ( User U sends the binary sequence of their identity to the PKG. (b) After receiving the PKG, it will randomly select... ,calculate: . (c) PKG calculation , It was secretly sent to user U.

5. The certificateless, authorized multi-identity cross-domain authentication scheme combining blockchain as described in claim 1, characterized in that, Step (4) includes the following steps: (a) User U received Selected Calculate its complete private key ,calculate Then, it requests polynomial invocation permission from PKG. After receiving the request, PKG selects t distinct integers. ,in Construct a polynomial of order t-1: And provide users with calling permissions, allowing users to make local calls. To complete the calculation. For User U randomly selects ,calculate In a finite field Searching for , making ,save p represents a large prime number. (b) Simultaneously, the user sends a parameter generation request to the PKG, and the user calculates... = , and Representing part of the user's identity and The weight value, and the serial number of all user identities. and Secretly sent to PKG, regarding identity and After receiving the request, PKG randomly selects t distinct integers. Construct a polynomial of degree t-1: .calculate , , PKG will It is sent secretly to the user. (c) A user's partial identity and its corresponding identity credibility weight constitute the corresponding weight set. ,in , This represents the total number of partial identities for a user. User U is calculated as follows: in and Mutual elements, let express The coefficient vector, , It can be represented as: User U's partial identity The private key is: .make: . User U Computing ,calculate: The Euclidean algorithm can be used to calculate the expression that satisfies the given conditions. of , thus calculating Save collection Used to generate signatures.

6. The certificateless, authorized multi-identity cross-domain authentication scheme combining blockchain as described in claim 1, characterized in that, Step (5) includes the following steps: At this point, a user needs to generate a signature to verify their identity, and they select a portion of their identity set. , Participate in signature generation. Receive set. The process of generating the post-signature is as follows: (a) The message to be signed is ,in For an integer, representing identity User calculation: . (b) User calculation: The final signature is .

7. The certificateless, authorized multi-identity cross-domain authentication scheme combining blockchain as described in claim 1, characterized in that, Step (6) mainly includes the following steps: For publicly disclosed identity values The signer U1, if the set of identities involved in generating the signature... If the total weight is greater than or equal to the threshold t, then the signature is received by the signature verifier U2. Then, we can verify that the following equation holds true: If this equation is true, then the authentication is successful.

8. A certificateless, authorized, multi-identity cross-domain authentication system combining blockchain, characterized in that: It includes a key generation center, a blockchain, a registration center, and users who need to be authenticated. The key generation center includes: System parameter generation module: used to select and generate system parameters and upload them to the blockchain. Partial key generation module: Used to generate partial private key information for users. Blockchain includes: Public parameter storage and sharing module: Used to store and easily share system parameters, ensuring that the parameters are immutable. The registration center includes: User registration module: Used to complete user registration and identity management. Weight Calculation and Distribution Module: This module is used to calculate and distribute the weights of each part of a user's identity and select appropriate system thresholds. Users requiring authentication include: Key Management Module: Used to calculate and store the complete keys for each part of a user's identity. Signature module: Used to generate digital signatures. Verification module: Used to verify digital signatures.

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