Lattice-based condition privacy protection certificateless proxy authentication method for Internet of Vehicles

Abstract

The invention provides an Internet of Vehicles lattice-based condition privacy protection certificateless proxy authentication method, which comprises the following steps of: generating a hash function, a main public key and a private key of a tracking server through a key generation center, and forming a system public parameter based on the hash function; based on an anonymization request initiated by a vehicle, a pseudo name of the vehicle is generated through a tracking server in combination with a system public parameter; a vehicle, a roadside unit and an application server are interacted with a key generation center, and respective public and private key pairs are generated in combination with system public parameters; the roadside unit interacts with the vehicle, and generates a proxy key of the vehicle and a proxy public key of the vehicle by using the system public parameters; a signcryption result is generated for the vehicle through the roadside unit, and the signcryption result is sent to the application server to be verified and received; and the real identity information of the vehicle is obtained through the tracking server. According to the invention, based on the certificateless password, the security problems of certificate management and key escrow are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle authentication in connected vehicles, and in particular to a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method. Background Art

[0002] The Internet of Vehicles (IoV) is a key component of the intelligent transportation system. IoVs usually include application servers, roadside units, and vehicles equipped with onboard units. Application servers have sufficient processing power, storage capacity, and computing resources to collect traffic information and support traffic control operations. Roadside units are generally deployed beside the road and serve as relay nodes for vehicles to communicate with application servers. In IoVs, communication between vehicles and roadside units generally uses dedicated short-range communication protocols. Since the protocol uses a public wireless channel, attackers can carry out various attacks. This poses a challenge to the security of IoVs, and it is particularly important to take effective security measures to prevent these attacks.

[0003] In the Internet of Vehicles, anonymous authentication of traffic messages and vehicle privacy protection are the main concerns of Internet of Vehicles security. On the one hand, it is necessary to ensure that relevant traffic messages are sent by legitimate vehicles rather than malicious vehicles. Authentication is a key content of Internet of Vehicles security. On the other hand, the messages transmitted by vehicles contain some sensitive information, such as vehicle identity, location, parking duration and route. Attackers may infer sensitive information of vehicles from Internet of Vehicles data, such as identity information, location data and driving trajectory, and then perform illegal tracking and give user portraits. Internet of Vehicles must meet privacy protection requirements.

[0004] However, in the event of a dispute or traffic accident, the true identity of the vehicle must be revealed. Therefore, the Internet of Vehicles needs to balance the relationship between authentication and conditional privacy protection. Summary of the invention

[0005] In view of the above situation, the main purpose of the present invention is to propose a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method to solve the above technical problems.

[0006] The present invention proposes a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method, the method comprising the following steps: Step 1: Generate a hash function, a master public key, and a private key of the tracking server through the key generation center, and then use the hash function to form the system public parameters; Step 2: The vehicle initiates an anonymization request, and the tracking server generates a pseudonym for the vehicle based on the system public parameters; Step 3: The vehicle, roadside unit and application server interact with the key generation center, and the public and private key pairs of the vehicle, the roadside unit and the application server are generated respectively based on the system public parameters; Step 4: The roadside unit interacts with the vehicle, and generates a proxy key and a proxy public key of the vehicle using system public parameters based on the public-private key pair of the vehicle, the public-private key pair of the roadside unit, and the public-private key pair of the application server; Step 5: Generate a signcryption result for the vehicle through the roadside unit, send the signcryption result to the application server, and the application server verifies the signcryption result using the vehicle's proxy key and the vehicle's proxy public key; Step 6: After the verification is passed, the application server receives the signature result and then sends the pseudonym of the vehicle to the tracking server. The tracking server obtains the real identity information of the vehicle through the pseudonym of the vehicle.

[0007] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention is based on certificate-free cryptography, which solves the security issues of certificate management and key escrow; 2. The proxy authentication scheme of the present invention based on the ISIS cipher can effectively resist quantum attacks; 3. The present invention supports conditional privacy protection, effectively balancing the relationship between security authentication and privacy protection; 4. Compared with other lattice-based authentication schemes, the computational overhead and communication overhead of the present invention are relatively low, and it can be applied to the Internet of Vehicles environment.

[0008] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description or learned through embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a flow chart of a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method proposed by the present invention; Figure 2 A schematic diagram showing the comparison of the computational efficiency of different schemes; Figure 3 Schematic diagram for comparing the communication overhead of different schemes. DETAILED DESCRIPTION

[0010] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0011] These and other aspects of the embodiments of the present invention will be apparent with reference to the following description and accompanying drawings. In these descriptions and accompanying drawings, some specific implementations of the embodiments of the present invention are specifically disclosed to represent some ways of implementing the principles of the embodiments of the present invention, but it should be understood that the scope of the embodiments of the present invention is not limited thereto.

[0012] See also Figure 1 The embodiment of the present invention provides a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method, the method comprising the following steps: Step 1: Generate a hash function, a master public key, and a private key of the tracking server through the key generation center, and then use the hash function to form the system public parameters; In step 1, the key generation center generates a hash function, a master public key, and a private key of the tracking server, and then the system public parameters are formed through the hash function. The specific steps are as follows: The key generation center selects system security parameters, sets approximate values ​​based on the security parameters, and then selects large prime numbers, integers, and full-rank random matrices through the approximate values; The key generation center generates five different hash functions by setting approximate values, large prime numbers, integers, and row-full-rank random matrices. The corresponding relationship in the process is: ; in, , , , and represent the first Hash function, the second Hash function, the third Hash function, the fourth Hash function and the fifth Hash function respectively, represents the ring of large prime integers, represents a vector of integer dimension, Represents the ring of large prime integers after removing 0, Represents a binary string of arbitrary length, represents an integer, Represents large prime numbers; The key generation center selects a random column vector and combines it with a full-rank random matrix to generate the master public key. The corresponding process has the following relationship: ; in, Represents the master public key, represents the modulo operation, represents the transpose of a random column vector, represents the transpose symbol, represents a random matrix with full row rank; The tracking server selects a random column vector and combines it with a full-rank random matrix to generate the private key of the tracking server. The corresponding process has the following relationship: ; in, Represents the private key of the tracking server, represents the transpose of a random column vector; The key generation center generates system public parameters by combining the first to fifth hash functions, a large prime number, a row full rank random matrix, a master public key and an integer.

[0013] Step 2: The vehicle initiates an anonymization request, and the tracking server generates a pseudonym for the vehicle based on the system public parameters; In step 2, the vehicle initiates an anonymization request, and the tracking server generates a pseudonym for the vehicle based on the system public parameters. The specific steps are as follows: The vehicle selects a secret random column vector, and based on the secret random column vector and the row full-rank random matrix in the system public parameters, the first part of the pseudonym of the vehicle is obtained by calculation. The corresponding process has the following relationship: ; in, The first part of the pseudonym of the vehicle. represents a secret random column vector; Sending the real identity information of the vehicle and the first part of the pseudonym of the vehicle to the tracking server; The tracking server calculates and obtains the second part of the pseudonym of the vehicle using the first hash function according to the real identity information of the vehicle, the first part of the pseudonym of the vehicle, the private key of the tracking server and the public key of the tracking server. The corresponding process has the following relationship: ; in, The second part of the pseudonym representing the vehicle, Indicates the real identity information of the vehicle. Represents the exclusive OR operation; The pseudo name of the vehicle is obtained by combining the first part of the pseudo name of the vehicle and the second part of the pseudo name of the vehicle. The relationship between the corresponding process is: ; in, Indicates a pseudonym for the vehicle.

[0014] Step 3: The vehicle, roadside unit and application server interact with the key generation center, and the public and private key pairs of the vehicle, the roadside unit and the application server are generated in combination with the system public parameters; In step 3, the vehicle, roadside unit and application server interact with the key generation center, and the public and private key pairs of the vehicle, the roadside unit and the application server are generated respectively based on the system public parameters. The specific steps are as follows: The second part of the public key is obtained by calculation based on the secret random column vector and the row full-rank random matrix in the system public parameters. The corresponding process has the following relationship: ; in, The second part of the public key of the object. represents the transpose of the secret random column vector; If the object is a roadside unit or an application server, the second part of the public key and the identity information of the object are sent to the key generation center; if the object is a vehicle, the second part of the public key and the pseudonym of the object are sent to the key generation center; After the key generation center receives the second part of the public key and identity information or pseudonym of the object, it calculates the first part of the public key based on the random column vector and the row full rank random matrix in the system public parameters. The corresponding process has the following relationship: ; in, represents the first part of the public key of the object, represents the transpose of a random column vector; If the object is a roadside unit or an application server, the key generation center calculates the first hash value through the second hash function based on the identity information, the first part of the public key and the second part of the public key. The corresponding process has the following relationship: ; in, represents the first hash value, Represents the identity information of the object; If the object is a vehicle, the key generation center calculates the first hash value through the second hash function based on the pseudonym, the first part of the public key and the second part of the public key. The corresponding process has the following relationship: ; in, A pseudo-name representing an object; The key generation center calculates the first part of the private key based on the random column vector, the first hash value and the master private key. The corresponding process has the following relationship: ; in, The first part of the private key of the object. represents a random column vector; The key generation center sends Send to object; The object is verified by calculating the second hash function Whether it is effective or not, the relationship between the corresponding process is: ; in, represents the transpose of the first part of the private key of the object; Verification passed, the object gets the private key and the public key .

[0015] Step 4: The roadside unit interacts with the vehicle, and generates a proxy key and a proxy public key of the vehicle using system public parameters based on the public-private key pair of the vehicle, the public-private key pair of the roadside unit, and the public-private key pair of the application server; In step 4, the roadside unit interacts with the vehicle, and based on the public-private key pair of the vehicle, the public-private key pair of the roadside unit, and the public-private key pair of the application server, the vehicle's proxy key and the vehicle's proxy public key are generated using the system public parameters. The specific steps are as follows: The vehicle obtains the column vector by calculating the random column vector and the row full-rank random matrix in the system common parameters. The corresponding process has the following relationship: ; in, represents the column vector obtained by calculation, represents a random column vector, represents the transpose of a column vector; The vehicle selects the proxy credential, which includes the proxy authentication information type, the vehicle's pseudonym, the vehicle's public key, the roadside unit's identity information, the roadside unit's public key, and the validity period of the proxy authentication; Based on the proxy credentials and the column vector obtained by calculation, the second hash value is calculated by the third hash function. The relationship between the corresponding process is: ; in, represents the second hash value, Indicates the proxy credentials; The proxy information is obtained based on the random column vector, the second hash value and the private key of the vehicle. The corresponding process has the following relationship: ; in, represents the private key of the vehicle, Indicates agent information; Aggregating the proxy information, the proxy credential, and the column vector to generate proxy authentication information, and sending the proxy authentication information to the roadside unit; The roadside unit calculates the third hash value through the third hash function according to the proxy authentication information. The relationship between the corresponding process is: ; in, represents the third hash value; The roadside unit verifies the proxy information according to the third hash value, and the corresponding process has the following relationship: ; in, Represents the transposition of the proxy information; Based on the pseudonym of the vehicle, the identity information of the roadside unit, the public key of the vehicle and the public key of the roadside unit, a fourth hash value is calculated by a fourth hash function, and the relationship between the corresponding process is: ; in, represents the fourth hash value, Indicates the pseudonym of the vehicle. represents the public key of the vehicle, The public key representing the roadside unit; Based on the proxy information, the fourth hash value and the private key of the roadside unit, the proxy key of the vehicle is calculated, and the relationship between the corresponding process is: ; in, represents the proxy key of the vehicle, Represents the private key of the roadside unit; The proxy public key of the vehicle is obtained based on the proxy key of the vehicle and the row full rank random matrix. The corresponding process has the following relationship: ; in, represents the vehicle's proxy public key, Represents the transpose of the vehicle's proxy key.

[0016] Step 5: Generate a signcryption result for the vehicle through the roadside unit, send the signcryption result to the application server, and the application server verifies the signcryption result using the vehicle's proxy key and the vehicle's proxy public key; In step 5, the roadside unit generates a signcryption result for the vehicle, and sends the signcryption result to the application server. The application server verifies the signcryption result using the vehicle's proxy key and the vehicle's proxy public key. The specific steps are as follows: The roadside unit selects two random column vectors, calculates the two random column vectors respectively, and obtains two column vectors obtained by modular operation. The relationship between the corresponding process is: ; in, and Both represent column vectors obtained through modular operations, represents the transpose of a random column vector, and All represent random column vectors; Based on the identity information of the application server and the public key of the application server, the fifth hash value is calculated and obtained by the second hash function. The relationship between the corresponding process is: ; in, represents the fifth hash value, represents the public key of the reference server, Indicates the identity information of the application server; The symmetric key is obtained by using the public key of the application server, the fifth hash value, the master public key and the random column vector. The corresponding process has the following relationship: ; in, Represents a symmetric key; The proxy credentials and messages are encrypted using a symmetric key to obtain the ciphertext. The corresponding process has the following relationship: ; in, Represents ciphertext, Indicates information, Indicates that encryption operation is performed using a symmetric key; Based on the message, the proxy credential, the two column vectors obtained by the modular operation, the public key of the application server, the column vector and the symmetric key, the sixth hash value is calculated and obtained by the fifth hash function. The relationship between the corresponding process is: ; in, represents the sixth hash value; The signature is obtained using the random column vector, the sixth hash value and the proxy key. The corresponding process has the following relationship: ; in, Indicates signature; The ciphertext, two column vectors obtained by modular operation, proxy credentials, random vectors and signature are collected to generate a signcryption result, and the signcryption result is sent to the application server; After receiving the signcryption result, the application server uses the private key of the application server and the column vector obtained by the modular operation to obtain the updated symmetric key. The corresponding process has the following relationship: ; in, represents the updated symmetric key, represents the transposition of the private key of the application server; Use the updated symmetric key to decrypt the ciphertext and obtain the decryption proxy certificate and decrypted message. The corresponding process has the following relationship: ; in, Indicates the decrypted proxy credentials, Represents the decrypted message, Indicates the use of a symmetric key for decryption operations; The seventh hash value is calculated and obtained by using the decrypted message, the decrypted proxy certificate, the two column vectors obtained by the modular operation, the public key of the application server, the column vector and the updated symmetric key through the fifth hash function. The corresponding process has the following relationship: ; in, represents the seventh hash value; The signcryption result is verified based on the seventh hash value, and the corresponding relationship in the process is: ; in, Represents the transpose of the signature.

[0017] Step 6: After the verification is successful, the application server receives the signcryption result and then sends the pseudonym of the vehicle to the tracking server. The tracking server obtains the real identity information of the vehicle through the pseudonym of the vehicle. In step 6, after the verification is successful, the application server receives the signcryption result and then sends the pseudonym of the vehicle to the tracking server. The tracking server obtains the real identity information of the vehicle through the pseudonym of the vehicle. The specific steps are as follows: The application server sends the pseudonym of the vehicle to the tracking server; The tracking server uses the vehicle's pseudonym and the tracking server's public and private key pair to obtain the vehicle's real identity information. The corresponding process has the following relationship: ; in, Indicates the real identity information of the vehicle. Represents the public and private key pair of the tracking server.

[0018] For further information, please refer to Figure 2 , the computational efficiency of different schemes was compared experimentally. The experiment was programmed in Java, using the JPBC library, the operating system was Windows 10, the hardware environment was CPU: 1.8 GHz Intel(R)Core(TM) i7-8550U, memory: 16GB, and the selected security parameters were .

[0019] For further information, please refer to Figure 3, the communication overhead of different schemes is compared, among which the security parameters used in the statistics are .

[0020] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0021] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0022] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method, characterized in that: The method comprises the following steps: Step 1: Generate a hash function, a master public key, and a private key of the tracking server through the key generation center, and then use the hash function to form the system public parameters; Step 2: The vehicle initiates an anonymization request, and the tracking server generates a pseudonym for the vehicle based on the system public parameters; Step 3: The vehicle, roadside unit and application server interact with the key generation center, and the public and private key pairs of the vehicle, the roadside unit and the application server are generated respectively based on the system public parameters; Step 4: The roadside unit interacts with the vehicle, and generates a proxy key and a proxy public key of the vehicle using system public parameters based on the public-private key pair of the vehicle, the public-private key pair of the roadside unit, and the public-private key pair of the application server; Step 5: Generate a signcryption result for the vehicle through the roadside unit, send the signcryption result to the application server, and the application server verifies the signcryption result using the vehicle's proxy key and the vehicle's proxy public key; Step 6: After the verification is passed, the application server receives the signature result and then sends the pseudonym of the vehicle to the tracking server. The tracking server obtains the real identity information of the vehicle through the pseudonym of the vehicle.

2. According to claim 1, a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method is characterized in that: In step 1, a hash function, a master public key, and a private key of a tracking server are generated by a key generation center, and then a system public parameter is formed by a hash function. The specific steps are as follows: The key generation center selects system security parameters, sets approximate values ​​based on the security parameters, and then selects large prime numbers, integers, and full-rank random matrices through the approximate values; The key generation center generates five different hash functions by setting large prime numbers and integers. The corresponding relationship between the processes is: ； in, , , , and represent the first Hash function, the second Hash function, the third Hash function, the fourth Hash function and the fifth Hash function respectively, represents the ring of large prime integers, represents a vector of integer dimension, Represents the ring of large prime integers after removing 0, Represents a binary string of arbitrary length, represents an integer, Represents large prime numbers; The key generation center selects a random column vector and combines it with a full-rank random matrix to generate the master public key. The corresponding process has the following relationship: ； in, Represents the master public key, represents the modulo operation, represents the transpose of a random column vector, represents the transpose symbol, represents a random matrix with full row rank; The tracking server selects a random column vector and combines it with a full-rank random matrix to generate the private key of the tracking server. The corresponding process has the following relationship: ； in, Represents the private key of the tracking server, represents the transpose of a random column vector; The key generation center generates system public parameters by combining the first to fifth hash functions, a large prime number, a row full rank random matrix, a master public key and an integer.

3. According to claim 2, a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method is characterized in that: In step 2, the vehicle initiates an anonymization request, and the tracking server generates a pseudonym for the vehicle based on the system public parameters. The specific steps are as follows: The vehicle selects a secret random column vector, and based on the secret random column vector and the row full-rank random matrix in the system public parameters, the first part of the pseudonym of the vehicle is obtained by calculation. The corresponding process has the following relationship: ； in, The first part of the pseudonym of the vehicle. represents a secret random column vector; Sending the real identity information of the vehicle and the first part of the pseudonym of the vehicle to the tracking server; The tracking server calculates and obtains the second part of the pseudonym of the vehicle using the first hash function according to the real identity information of the vehicle, the first part of the pseudonym of the vehicle, the private key of the tracking server and the public key of the tracking server. The corresponding process has the following relationship: ； in, The second part of the pseudonym representing the vehicle, Indicates the real identity information of the vehicle. Represents the exclusive OR operation; The pseudo name of the vehicle is obtained by combining the first part of the pseudo name of the vehicle and the second part of the pseudo name of the vehicle. The relationship between the corresponding process is: ； in, Indicates a pseudonym for the vehicle.

4. According to claim 3, a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method is characterized in that: In step 3, the vehicle, roadside unit and application server interact with the key generation center, and the public and private key pairs of the vehicle, the roadside unit and the application server are generated respectively in combination with the system public parameters. The specific steps are as follows: The second part of the public key is obtained by calculation based on the secret random column vector and the row full-rank random matrix in the system public parameters. The corresponding process has the following relationship: ； in, The second part of the public key of the object. represents the transpose of the secret random column vector; If the object is a roadside unit or an application server, the second part of the public key and the identity information of the object are sent to the key generation center; if the object is a vehicle, the second part of the public key and the pseudonym of the object are sent to the key generation center; After the key generation center receives the second part of the public key and identity information or pseudonym of the object, it calculates the first part of the public key based on the random column vector and the row full rank random matrix in the system public parameters. The corresponding process has the following relationship: ； in, represents the first part of the public key of the object, represents the transpose of a random column vector; If the object is a roadside unit or an application server, the key generation center calculates the first hash value through the second hash function based on the identity information, the first part of the public key and the second part of the public key. The corresponding process has the following relationship: ； in, represents the first hash value, Represents the identity information of the object; If the object is a vehicle, the key generation center calculates the first hash value through the second hash function based on the pseudonym, the first part of the public key and the second part of the public key. The corresponding process has the following relationship: ； in, A pseudo-name representing an object; The key generation center calculates the first part of the private key based on the random column vector, the first hash value and the master private key. The corresponding process has the following relationship: ； in, The first part of the private key of the object. represents a random column vector; The key generation center sends Send to object; The object is verified by calculating the second hash function Whether it is effective or not, the relationship between the corresponding process is: ； in, represents the transpose of the first part of the private key of the object; Verification passed, the object gets the private key and the public key .

5. According to claim 4, a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method is characterized in that: In step 4, the roadside unit interacts with the vehicle, and based on the public-private key pair of the vehicle, the public-private key pair of the roadside unit, and the public-private key pair of the application server, the vehicle's proxy key and the vehicle's proxy public key are generated using the system public parameters. The specific steps are as follows: The vehicle obtains the column vector by calculation based on the random column vector and the row full-rank random matrix in the system common parameters. The corresponding process has the following relationship: ； in, represents the column vector obtained by calculation, represents a random column vector, represents the transpose of a column vector; Based on the proxy credentials and the column vector obtained by calculation, the second hash value is calculated by the third hash function. The relationship between the corresponding process is: ； in, represents the second hash value, Indicates the proxy credentials; The proxy information is obtained based on the random column vector, the second hash value and the private key of the vehicle. The corresponding process has the following relationship: ； in, represents the private key of the vehicle, Indicates agent information; Aggregating the proxy information, the proxy credential, and the column vector to generate proxy authentication information, and sending the proxy authentication information to the roadside unit; The roadside unit calculates the third hash value through the third hash function according to the proxy authentication information. The relationship between the corresponding process is: ； in, represents the third hash value; The roadside unit verifies the proxy information according to the third hash value, and the corresponding process has the following relationship: ； in, Represents the transposition of the proxy information; Based on the pseudonym of the vehicle, the identity information of the roadside unit, the public key of the vehicle and the public key of the roadside unit, a fourth hash value is calculated by a fourth hash function, and the relationship between the corresponding process is: ； in, represents the fourth hash value, Indicates the pseudonym of the vehicle. represents the public key of the vehicle, The public key representing the roadside unit; Based on the proxy information, the fourth hash value and the private key of the roadside unit, the proxy key of the vehicle is calculated, and the relationship between the corresponding process is: ； in, represents the proxy key of the vehicle, Represents the private key of the roadside unit; The proxy public key of the vehicle is obtained based on the proxy key of the vehicle and the row full rank random matrix. The corresponding process has the following relationship: ； in, represents the vehicle's proxy public key, Represents the transpose of the proxy key for the vehicle.

6. According to claim 5, a vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method is characterized in that: In step 5, a signcryption result is generated for the vehicle by the roadside unit, and the signcryption result is sent to the application server. The application server verifies the signcryption result using the vehicle's proxy key and the vehicle's proxy public key. The specific steps are as follows: The roadside unit selects two random column vectors, calculates the two random column vectors respectively, and obtains two column vectors obtained by modular operation. The relationship between the corresponding process is: ； in, and Both represent column vectors obtained through modular operations, represents the transpose of a random column vector, and All represent random column vectors; Based on the identity information of the application server and the public key of the application server, the fifth hash value is calculated and obtained by the second hash function. The relationship between the corresponding process is: ； in, represents the fifth hash value, represents the public key of the reference server, Indicates the identity information of the application server; The symmetric key is obtained by using the public key of the application server, the fifth hash value, the master public key and the random column vector. The corresponding process has the following relationship: ； in, Represents a symmetric key; The proxy credentials and messages are encrypted using a symmetric key to obtain the ciphertext. The corresponding process has the following relationship: ； in, Represents ciphertext, Indicates information, Indicates that encryption operation is performed using a symmetric key; Based on the message, the proxy credential, the two column vectors obtained by the modular operation, the public key of the application server, the column vector and the symmetric key, the sixth hash value is calculated and obtained by the fifth hash function. The relationship between the corresponding process is: ； in, Represents the sixth hash value.

7. The vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method according to claim 6, characterized in that: Generate a signcryption result for the vehicle through the roadside unit, send the signcryption result to the application server, and the application server verifies the signcryption result using the vehicle's proxy key and the vehicle's proxy public key, which also includes the following steps: The signature is obtained using the random column vector, the sixth hash value and the vehicle's proxy key. The corresponding process has the following relationship: ； in, Indicates signature; The ciphertext, two column vectors obtained by modular operation, proxy credentials, random vectors and signature are collected to generate a signcryption result, and the signcryption result is sent to the application server; After receiving the signcryption result, the application server uses the private key of the application server and the column vector obtained by the modular operation to obtain the updated symmetric key. The corresponding process has the following relationship: ； in, represents the updated symmetric key, represents the transposition of the private key of the application server; Use the updated symmetric key to decrypt the ciphertext and obtain the decryption proxy certificate and decrypted message. The corresponding process has the following relationship: ； in, Indicates the decrypted proxy credentials, Represents the decrypted message, Indicates the use of a symmetric key for decryption operations; The seventh hash value is calculated and obtained by using the decrypted message, the decrypted proxy certificate, the two column vectors obtained by the modular operation, the public key of the application server, the column vector and the updated symmetric key through the fifth hash function. The corresponding process has the following relationship: ； in, represents the seventh hash value; The signcryption result is verified based on the seventh hash value, and the corresponding relationship in the process is: ； in, Represents the transpose of the signature.

8. The vehicle-connected grid-based conditional privacy protection certificateless proxy authentication method according to claim 7, characterized in that: In step 6, after verification, the application server receives the signcryption result, and then sends the pseudonym of the vehicle to the tracking server. The tracking server obtains the real identity information of the vehicle through the pseudonym of the vehicle. The specific steps are as follows: The application server sends the pseudonym of the vehicle to the tracking server; The tracking server uses the vehicle's pseudonym and the tracking server's public and private key pair to obtain the vehicle's real identity information. The corresponding process has the following relationship: ； in, Indicates the real identity information of the vehicle. Represents the public and private key pair of the tracking server.

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