Identity-based matching encryption method, system and device without trusted center, and storage medium
By employing an identity-based matching encryption method without a trusted central authority, and utilizing public parameters generated by a key administrator and public-private key pairs generated locally by users, the problems of key leakage and dynamic member management in traditional matching encryption schemes are solved. This achieves data confidentiality and two-way access control, adapting to dynamic network environments.
Patent Information
- Application Number
- CN202511125592.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2025-07-21
- Filing Date
- 2025-08-12
- Publication Date
- 2025-11-11
AI Technical Summary
Existing matching encryption schemes rely on trusted centers, leading to problems such as key leakage and data tampering. Furthermore, they lack a flexible and efficient dynamic member management mechanism, which affects system security and availability.
It adopts an identity-based matching encryption method without a trusted central authority, utilizes an honest and curious entity key administrator to generate public parameters, and allows users to generate public-private key pairs and auxiliary information locally, thereby achieving two-way access control and dynamic member management.
It achieves data confidentiality and non-forgeability in an environment without a trusted central authority, supports efficient two-way access control and dynamic member management, and solves the problems of key escrow and dynamic member entry and exit.
Smart Images
Figure CN120934749A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of information security and relates to an identity base matching encryption method, system, device and storage medium without a trusted center. Background Technology
[0002] The concept of matching encryption was first proposed by Ateniese et al., in which the sender can select a target receiver based on specific preferences, while the receiver can verify whether the ciphertext indeed comes from the intended sender. This two-way verification mechanism gives both parties sharing data equal control capabilities, ensuring that the sender can accurately control the flow of data on the one hand, and that the receiver can confirm the authenticity of the data source on the other. This dual control feature can effectively resist common attacks such as denial-of-service attacks. With the popularization of dynamic network environments such as in-vehicle social networks, the shortcomings of traditional matching encryption schemes that rely on a trusted center to distribute keys are gradually becoming apparent. Once the central node is attacked, fails, or abuses its privileges, it will not only lead to problems such as key leakage and data tampering, but may also have a catastrophic impact on the security and availability of the entire system. In addition, existing schemes generally lack flexible and efficient dynamic member management mechanisms, which cannot adapt to the actual needs of frequent node changes, leading to a waste of a lot of computing and communication resources, and thus causing problems such as increased data access latency and slower system response, seriously affecting the actual deployment effect. Therefore, it is crucial to reduce the dependence on a trusted center while ensuring the verifiability of the sender and supporting efficient dynamic member management.
[0003] Although several identity-based matching encryption schemes with different forms and properties have been proposed, there is currently no decentralized identity-based matching encryption scheme. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an identity base matching encryption method, system, device and storage medium without a trusted center, which can achieve two-way access control, no trusted center and dynamic member management while ensuring data confidentiality and non-forgeability.
[0005] To achieve the above objectives, the present invention employs the following technical solution: An identity-based matching encryption method without a trusted central authority includes the following steps: The key administrator generates public parameters; The data owner and the data requester each generate a public-private key pair and auxiliary information; The key administrator generates a master public key and a secondary key based on public parameters, the public key, and auxiliary information; The data owner uses the master public key, the auxiliary key, the data owner's identity information, the target data requester's identity information, and the data owner's private key to encrypt the message and generate ciphertext; The data requester uses a helper key, the data requester's private key, and the identity information of the target data owner to decrypt the ciphertext and generate a plaintext message.
[0006] Preferably, the steps for the key administrator to generate public parameters include: setting security parameters and a user limit; randomly selecting two hash functions to generate a multiplicative cyclic group and a bilinear mapping, wherein the order of the multiplicative cyclic group is a prime number, and setting the generator of the multiplicative cyclic group; and using the above parameters as public parameters.
[0007] Preferably, the steps for the data owner and data requester to generate public-private key pairs and auxiliary information include: calculating the public key and auxiliary information based on user identity information and public parameters.
[0008] Preferably, the steps for the key administrator to generate the primary public key and the auxiliary key include: after receiving the public key and auxiliary information of at least one user, the key administrator verifies them; after successful verification, the key administrator calculates and updates the primary public key and the auxiliary key.
[0009] Preferably, the data encryption steps include: the data owner finding a matching index based on the data owner's identity information and the target data requester's identity information; the data owner randomly selecting and calculating multiple components to generate ciphertext.
[0010] Preferably, the data decryption steps include: the data requester finding a matching index based on the identity information of the target data owner; the data requester using the auxiliary key and the data requester's private key to calculate intermediate results and recover the plaintext message from the ciphertext.
[0011] Preferably, the method also includes a user logout step: when a user logs out, the key administrator updates the primary public key and secondary key based on the user's identity information and public key, generating updated primary public key and updated secondary key.
[0012] An identity-based matching encryption system without a trusted central authority includes: The public parameter generation module is used by key administrators to generate public parameters. The public-private key pair generation module is used by the data owner and the data requester to generate public-private key pairs and auxiliary information respectively. The master public key generation module is used by key administrators to generate master public keys and auxiliary keys based on public parameters, public keys, and auxiliary information. The ciphertext generation module is used by the data owner to encrypt messages using the master public key, the auxiliary key, the data owner's identity information, the target data requester's identity information, and the data owner's private key to generate ciphertext. The plaintext generation module is used by the data requester to decrypt the ciphertext using the auxiliary key, the data requester's private key, and the identity information of the target data owner, and generate a plaintext message.
[0013] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the identity base matching encryption method without a trusted center.
[0014] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the identity base matching encryption method without a trusted center.
[0015] Compared with the prior art, the present invention has the following beneficial effects: This invention replaces the traditional trusted center with an honest and curious entity key administrator. The key administrator does not distribute keys but is only responsible for performing publicly verifiable operations. Keys are generated locally by the user, thus solving the key escrow problem. Through the digital signature embedded by the data owner during encryption, the data requester can effectively determine the source and authenticity of the data, achieving two-way access control. The method of this invention is based on identity-based matching encryption and identity-based registration encryption technologies, which can achieve two-way access control while ensuring data confidentiality and non-forgeability. It eliminates the need for a trusted center and dynamic member management, solving the problems of key escrow and dynamic member entry and exit. Attached Figure Description
[0016] Figure 1 This is a flowchart of the identity base matching encryption method without a trusted center according to the present invention. Detailed Implementation
[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0018] like Figure 1 The diagram illustrates the identity-based matching encryption method without a trusted center described in this embodiment, which includes the following steps: System initialization steps: The key administrator generates public parameters based on security parameters and the total number of users, and publishes the generated public parameters to the users in the system.
[0019] Key generation steps: Users (data owners and data requesters) generate corresponding public and private key pairs and auxiliary information based on their identity information.
[0020] Key aggregation steps: The key administrator generates a master public key and a secondary key based on public parameters, the public key provided by the user, and auxiliary information.
[0021] Data encryption steps: The data owner generates ciphertext based on the master public key, auxiliary key, the data owner's identity information, the target data requester's identity information, the data owner's private key, and the message to be encrypted.
[0022] Data decryption steps: The data requester generates a plaintext message based on the auxiliary key, the data requester's private key, the identity information of the target data owner, and the ciphertext.
[0023] User logout process: The key administrator generates updated primary and secondary keys based on the primary public key, secondary key, the logout user's identity information and public key.
[0024] The following is a detailed description of each step: System initialization steps include: Step 1: Enter security parameters and user limit .
[0025] The second step is to Divided into sizes The number of groups is .
[0026] The third step is to randomly select two hash functions. and .
[0027] The fourth step is to generate the multiplication cyclic group. and bilinear mapping on ,in and The order is a prime number , For the group The generator.
[0028] Step 5, randomly select ,calculate .
[0029] Step 6: Output common parameters .
[0030] The key generation steps include: First step, input common parameters and user identity .
[0031] The second step is to select randomly. ,calculate , and ,in .
[0032] The third step is to output the public key. and auxiliary information Give it to the key administrator.
[0033] The key aggregation step includes: First step, input common parameters Identity information Public key and auxiliary information .
[0034] The second step is to define... , .
[0035] The third step is to... For all Random selection ,calculate , , and ,in .
[0036] Step 4, Analysis for Verify the equation Whether it is valid or not.
[0037] Fifth step, set ,calculate , Updated to .
[0038] Step 6, Analysis for For all ,calculate . Updated to and order .
[0039] Step 7: Output the master public key and auxiliary key .
[0040] if If it is the first identity, then perform all the above steps. If If it is not the first identity to register, then proceed with steps four, five, six, and seven above.
[0041] Data encryption steps include: First step, input common parameters Message to be encrypted The identity information of the data owner and private key The identity information of the target data requester .
[0042] The second step, from Find the equation that satisfies of ,in , , , .
[0043] The third step is to select randomly. ,calculate , , , , , and .
[0044] Step 4: Output ciphertext .
[0045] The data decryption steps include: First step, input common parameters Auxiliary key The private key of the data requester Identity information of the target data owner and ciphertext .
[0046] The second step, from Find the equation that satisfies of .
[0047] The third step is to calculate. .
[0048] Fourth step, output ciphertext data .
[0049] The user logout process includes: First step, input common parameters Master key Auxiliary key Logout user identity information and public key .
[0050] The second step is analysis. for ,in .
[0051] The third step is to apply the following to all ,calculate and , and Updated to , and order .
[0052] Step 4: Output the updated master key. and auxiliary key .
[0053] In the above formula, the parameters have the following meanings: Safety parameters; Assumed upper limit on the number of users; Number of user groups; The number of users in each group; : Secure hash function; : a large prime number; : Rank Multiplication cyclic group; :Depend on A set of integers; For the group Generators; Bilinear mapping; : Common parameters; Intermediate parameters used to generate the master public key and auxiliary information. User's identity information; The user's position within each group; Identity is User public key; Identity is The user key; Identity is User assistance information; The actual maximum number of users; The number of users currently in the system; : Master public key; Auxiliary key; : The public key of the virtual user in each group (used to hide the real user); : Components of the master public key (corresponding groups); : Components of the auxiliary key (corresponding groups); : The components of the auxiliary key (corresponding to a single user); Opening parameters introduced by vector commitment : Subscript used to indicate the data owner; : Used to indicate the index of the data requester; : The user's group number; Message to be encrypted; : Ciphertext, specifically including and Seven parts; : The updated master public key; : The updated auxiliary key.
[0054] The following are embodiments of the apparatus of the present invention, which can be used to execute embodiments of the method of the present invention. For details not omitted in the apparatus embodiments, please refer to the embodiments of the method of the present invention.
[0055] In another embodiment of the present invention, an identity base matching encryption system without a trusted center is provided. This identity base matching encryption system without a trusted center can be used to implement the above-mentioned identity base matching encryption method without a trusted center. Specifically, the identity base matching encryption system without a trusted center includes a public parameter generation module, a public-private key pair generation module, a master public key generation module, a ciphertext generation module, and a plaintext generation module.
[0056] The public parameter generation module is used by key administrators to generate public parameters.
[0057] The public-private key pair generation module is used by data owners and data requesters to generate public-private key pairs and auxiliary information, respectively.
[0058] The master public key generation module is used by key administrators to generate master public keys and auxiliary keys based on public parameters, public keys, and auxiliary information.
[0059] The ciphertext generation module is used by the data owner to encrypt messages using the master public key, the auxiliary key, the data owner's identity information, the target data requester's identity information, and the data owner's private key, thereby generating ciphertext.
[0060] The plaintext generation module is used by the data requester to decrypt the ciphertext using the auxiliary key, the data requester's private key, and the identity information of the target data owner, and generate a plaintext message.
[0061] In another embodiment of the present invention, a terminal device is provided, comprising a processor and a memory. The memory stores a computer program, the computer program including program instructions, and the processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), or field-programmable gate arrays (FPGAs). The processor, described in this embodiment of the invention, can be used for the operation of an identity-based matching encryption method without a trusted center. This includes: a key administrator generating public parameters; the data owner and data requester each generating public-private key pairs and auxiliary information; the key administrator generating a master public key and an auxiliary key based on the public parameters, public key, and auxiliary information; the data owner using the master public key, auxiliary key, data owner's identity information, target data requester's identity information, and data owner's private key to encrypt the message, generating ciphertext; and the data requester using the auxiliary key, data requester's private key, and target data owner's identity information to decrypt the ciphertext, generating a plaintext message.
[0062] In another embodiment, the present invention also provides a computer-readable storage medium (Memory), which is a memory device in a terminal device for storing programs and data. It is understood that the computer-readable storage medium here may include both the built-in storage medium in the terminal device and extended storage media supported by the terminal device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor, which may be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here may include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, and a read-only memory (ROM).
[0063] One or more instructions stored in a computer-readable storage medium can be loaded and executed by a processor to implement the corresponding steps of the identity-based matching encryption method without a trusted center in the above embodiments; one or more instructions in the computer-readable storage medium are loaded and executed by the processor to perform the following steps: the key administrator generates public parameters; the data owner and the data requester each generate public-private key pairs and auxiliary information; the key administrator generates a master public key and an auxiliary key based on the public parameters, public key, and auxiliary information; the data owner uses the master public key, auxiliary key, the data owner's identity information, the target data requester's identity information, and the data owner's private key to encrypt the message and generate ciphertext; the data requester uses the auxiliary key, the data requester's private key, and the target data owner's identity information to decrypt the ciphertext and generate a plaintext message.
[0064] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, etc.) containing computer-usable program code.
[0065] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0066] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0067] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0068] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.
[0069] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.
[0070] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.
[0071] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0072] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.
[0073] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this patent should not be determined by reference to the above description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.
Claims
1. A trusted-center-free identity-based matching encryption method, characterized in that, Includes the following processes: The key administrator generates public parameters; The data owner and the data requester each generate a public-private key pair and auxiliary information; The key administrator generates a master public key and a secondary key based on public parameters, the public key, and auxiliary information; The data owner uses the master public key, the auxiliary key, the data owner's identity information, the target data requester's identity information, and the data owner's private key to encrypt the message and generate ciphertext; The data requester uses a helper key, the data requester's private key, and the identity information of the target data owner to decrypt the ciphertext and generate a plaintext message.
2. The identity base matching encryption method without a trusted center according to claim 1, characterized in that, The steps for a key administrator to generate public parameters include: setting security parameters and a user limit; randomly selecting two hash functions to generate a multiplicative cyclic group and a bilinear mapping, wherein the order of the multiplicative cyclic group is a prime number, and setting the generator of the multiplicative cyclic group; and using the above parameters as public parameters.
3. The identity base matching encryption method without a trusted center according to claim 1, characterized in that, The steps for data owners and data requesters to generate public-private key pairs and auxiliary information include: calculating the public key and auxiliary information based on user identity information and public parameters.
4. The identity base matching encryption method without a trusted center according to claim 1, characterized in that, The steps for a key administrator to generate a primary public key and a secondary key include: after receiving the public key and secondary information of at least one user, the key administrator verifies them; after successful verification, the primary public key and the secondary key are calculated and updated.
5. The identity base matching encryption method without a trusted center according to claim 1, characterized in that, The steps of data encryption include: the data owner finding a matching index based on the data owner's identity information and the target data requester's identity information; the data owner randomly selecting and calculating multiple components to generate the ciphertext.
6. The identity base matching encryption method without a trusted center according to claim 1, characterized in that, The data decryption process includes: the data requester finding a matching index based on the identity information of the target data owner; the data requester using the auxiliary key and the data requester's private key to calculate intermediate results and recover the plaintext message from the ciphertext.
7. The identity base matching encryption method without a trusted center according to claim 1, characterized in that, It also includes a user logout step: when a user logs out, the key administrator updates the primary public key and secondary key based on the user's identity information and public key, generating updated primary public key and updated secondary key.
8. An identity-based matching encryption system without a trusted central authority, characterized in that, include: The public parameter generation module is used by key administrators to generate public parameters. The public-private key pair generation module is used by the data owner and the data requester to generate public-private key pairs and auxiliary information respectively. The master public key generation module is used by key administrators to generate master public keys and auxiliary keys based on public parameters, public keys, and auxiliary information. The ciphertext generation module is used by the data owner to encrypt messages using the master public key, the auxiliary key, the data owner's identity information, the target data requester's identity information, and the data owner's private key to generate ciphertext. The plaintext generation module is used by the data requester to decrypt the ciphertext using the auxiliary key, the data requester's private key, and the identity information of the target data owner, and generate a plaintext message.
9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the identity base matching encryption method without a trusted center as described in any one of claims 1 to 7.
10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the identity base matching encryption method without a trusted center as described in any one of claims 1 to 7.