An intelligent transportation certificate authentication and revocation method and device

Abstract

The present application discloses a method and device for intelligent transportation certificate authentication and revocation, which relates to the technical field of vehicle identity authentication. A signature certificate is generated to initialize the vehicle, and a vehicle registration certificate is obtained in combination with the signature certificate and sent to the vehicle; a pseudonym certificate is generated for the vehicle using the vehicle public key, SA, and PCA and fed back to SA; confirmation information is generated for all received pseudonym certificates, and the received pseudonym certificates are inserted into the database in the next update. At the same time, proofs are generated in batches for all pseudonym certificates; the pseudonym certificates and their proofs are obtained and information is shared with the verification agency. The verification agency authenticates the certificates and proofs and shares the certificates and proofs with the vehicles within the communication range, and revokes the certificates of malicious vehicles. The pseudonym certificate not only protects the privacy of the vehicle but also realizes vehicle correspondence. By revoking the pseudonym certificate, the vehicle's registration certificate is pulled into the blacklist, solving the problems of vehicle privacy leakage, identity verification, and difficulty in revoking malicious vehicles.

Description

Technical Field

[0001] This application relates to the technical field of vehicle identity authentication, and particularly relates to a method and device for intelligent transportation certificate authentication and revocation. Background Art

[0002] The intelligent transportation system effectively integrates advanced information technology, data communication technology, sensor technology, electronic control technology, computer technology, etc. into the entire transportation management system, thereby establishing a comprehensive transportation and management system that plays a role in a large range and in all directions, and is real-time, accurate, and efficient. While bringing convenience to urban traffic, the intelligent transportation system is also accompanied by security and privacy issues. On the one hand, open wireless communication may expose vehicle and infrastructure information to cyberattacks; on the other hand, the leakage of real identity information may lead to serious security and privacy risks.

[0003] To solve these problems, experts and scholars have now proposed different VPKI certificate revocation schemes to protect the communication security in the intelligent transportation system. The ETSI (European Telecommunications Standards Institute) system proposes to cancel the certificate status check to achieve the maximum number of authentications per second, and this system is a relatively simple VPKI solution. Further, Correia et al. proposed a range-based certificate revocation method to enhance its performance. In contrast, the SCMS (Supply Chain Management System) system proposed by Brecht et al. is more complex. It ensures the non-correlatability of the distribution between device certificates and provides stronger privacy protection. The SCMS system relies on the certificate revocation list and reduces the growth of the CRL by using a single revocation certificate. Rabiah et al. proposed TVSS (Token-based Vehicle Security System), which ensures scalable revocation and frequent certificate updates. However, the TVSS system relies on non-forgeable tokens to achieve faster verification. To protect identity privacy, Zhou et al. use pseudonym information to digitally sign vehicles in different regions, but adopt a one-by-one verification method when verifying the signature.

[0004] The above-mentioned solutions are all proposed for untrusted network communication. For cyberattacks on vehicle trust storage, how to propose an effective pseudonym certificate authentication and certificate revocation mechanism is a major challenge that needs to be solved in the current intelligent transportation system. Summary of the Invention

[0005] To solve the above technical problems, this application proposes the following technical solutions:

[0006] In a first aspect, an embodiment of the present application provides an intelligent transportation certificate authentication and revocation method, including:

[0007] Generate a signature certificate to initialize the vehicle and obtain a vehicle registration certificate in combination with the signature certificate and send it to the vehicle;

[0008] Generate a pseudonym certificate for the vehicle using the vehicle public key, a shuffling mechanism SA, and a pseudonym certificate authority PCA, store the pseudonym certificate, and feedback it to SA;

[0009] Generate confirmation information for all received pseudonym certificates, insert the received pseudonym certificates into the database in the next update, and generate proofs for all pseudonym certificates in batches;

[0010] Obtain the pseudonym certificate and its proof and share the information with a verification agency. The verification agency authenticates the certificate and the proof, shares the certificate and the proof with the vehicles within the communication range, and revokes the certificate of malicious vehicles.

[0011] In a possible implementation, the generating a signature certificate to initialize the vehicle and obtaining a vehicle registration certificate in combination with the signature certificate and sending it to the vehicle includes:

[0012] Embed a root certificate authority RCA that meets the trusted security standard into the blockchain;

[0013] RCA inserts the certificates of the registration certificate authority ECA and PCA that are authorized to sign into the blockchain, and at the same time delegates the signing right to the ECA and PCA;

[0014] The RCA generates a signature certificate for the trusted party and records it on the blockchain, and then initializes the vehicle using the signature certificate;

[0015] The vehicle generates a public key and sends it to the ECA for signature. The ECA generates a vehicle registration certificate according to the signature certificate, registers it in the distributed ledger CDLM, and at the same time sends the registration certificate to the vehicle.

[0016] In a possible implementation, the generating a pseudonym certificate for the vehicle using the vehicle public key, a shuffling mechanism SA, and a pseudonym certificate authority PCA, storing the pseudonym certificate, and feedbacking it to SA includes:

[0017] The vehicle sends the public key to the shuffling mechanism SA. SA uses the butterfly key expansion method to generate a public key seed, and sends the public key seed to the pseudonym certificate authority PCA for key signature;

[0018] The PCA generates a pseudonym certificate for the vehicle using the signed public key seed, stores the pseudonym certificate in the CDLM, and sends the certificate to the SA in ciphertext form.

[0019] In a possible implementation, the vehicle sends the public key to the shuffling authority SA, and the SA uses the butterfly key expansion method to generate a public key seed and sends the public key seed to the pseudonym certificate authority PCA for key signing, including:

[0020] The vehicle generates a public key (a, A.g) and generates a pseudonym certificate signature request using the (a, A.g). Forward it to the SA: ), where: Ecert is the vehicle's registration certificate, is the public key of the shuffling authority, is the vehicle's private key, is the signature function, is the encryption function;

[0021] The SA verifies that the vehicle's registration certificate has not been revoked and is the only pseudonym certificate signature request for the vehicle, and then uses the butterfly key expansion to generate n cocoon-shaped public keys;

[0022] The SA mixes the extended public keys from different vehicles and forwards the message to the PCA, , is the extended public key, is the public key of the PCA, is the registration certificate, is the pseudonym certificate signature request, is the hash function.

[0023] In a possible implementation, the PCA generates a pseudonym certificate for the vehicle using the signed public key seed, stores the pseudonym certificate in the CDLM, and sends the certificate to the SA in ciphertext form, including:

[0024] The PCA generates a pseudonym certificate , where metainfo is metadata, is the digital signature secret identifier, , , where: ri is a random number and g is a generator, is the digital signature;

[0025] The PCA sends the registration request message RegReq of the signed log to the CDLM, , where: is the public key of the CDLM;

[0026] The CDLM returns the signed timestamp of the registration request to the PCA , , where: t represents the current time, is the private key of the CDLM;

[0027] The PCA creates an encrypted package and returns it to the SA, , where: is 's public key;

[0028] After the SA accepts the said , it bundles for each vehicle for the vehicle to download;

[0029] The vehicle downloads the bundled encrypted package and decrypts through the decryption algorithm to obtain , where: represents the private key for decrypting ;

[0030] Finally, the SA executes and algorithms to verify the correctness of each pseudonym certificate and the corresponding , where is the verification function for verifying the digital signature.

[0031] In a possible implementation, generating confirmation information for all received pseudonym certificates, inserting the received pseudonym certificates into the database in the next update, and generating proofs for all pseudonym certificates in batches, including: The CDLM generates confirmation information for all received certificates and inserts the received certificates into the database in the next update. The update process is as follows: Let be the set of unexpired pseudonym certificates, then the new set of pseudonym certificates is , and the cumulative value is , , ,

[0032] , is the private key.

[0033] In a possible implementation, obtaining the pseudonym certificate and its proof and sharing information with the verification agency, and the verification agency authenticating the certificate and the proof and sharing the certificate and the proof with the vehicles within the communication range and revoking the certificate for malicious vehicles, including:

[0034] The aggregator downloads the newly inserted pseudonym certificates and their proofs from the blockchain and the CDLM and shares this information with the edge server;

[0035] The edge server verifies the batch proofs and the corresponding pseudonym certificates received from vehicles within the communication range;

[0036] Then the edge server generates a hash list of the pseudonym certificates in the communication proof and shares the hash list and the batch proofs with the vehicles within the communication range;

[0037] The vehicle verifies the pseudonym certificates according to the hash list shared by the edge server;

[0038] The vehicle caches the batch proofs and verifies whether the pseudonym certificates are revoked according to the batch proofs;

[0039] When it is found that the vehicle is using an unexpired pseudonym certificate and malicious behavior occurs, the vehicle and the pseudonym certificate are tracked, and the registration certificate is associated with the corresponding pseudonym certificate and listed in the blacklist.

[0040] In a possible implementation, the vehicle verifies the pseudonym certificates according to the hash list shared by the edge server, including:

[0041] Performing a hash process on the PCA certificate and comparing the hash value with the PCA certificate hash value recorded on the blockchain to check whether the PCA certificate is recorded in the blockchain;

[0042] Subsequently, each pseudonym certificate is hashed, and it is checked whether there is a hash value of the pseudonym certificate in the hash list shared by the edge server; if the hash value of the pseudonym certificate matches the hash value in the list, the pseudonym certificate is accepted as a valid certificate.

[0043] In a possible implementation, the when it is found that the vehicle is using an unexpired pseudonym certificate and malicious behavior occurs, the vehicle and the pseudonym certificate are tracked, and the registration certificate is associated with the corresponding pseudonym certificate and listed in the blacklist, including:

[0044] The edge server sends the hash value to the PCA to request to map the pseudonym certificate to the PSR;

[0045] The SA forwards the list of the registration certificate and the PSR hash value ;

[0046] The PCA further connects the set of pseudonym certificates to the list of the PSR hash value and forwards them to the CDLM for revocation operation.

[0047] In a possible implementation, the PCA further connects the set of pseudonym certificates to the list of the PSR hash value and forwards them to the CDLM for revocation operation, including:

[0048] Calculate the new list The new cumulative value, and delete the set of pseudonym certificates belonging to malicious vehicles in the CDLM ledger: where: L is the list of pseudonym certificates, is the list of pseudonym certificates to be deleted;

[0049] Delete the pseudonym certificate from the CDLM database, then stop using the malicious vehicle and add it to the blacklist;

[0050] The SA side retains the registration certificate and the corresponding hash value of the record, while the PCA only retains the mapping of the pseudonym certificate and the related hash value of the mapping.

[0051] In a second aspect, an embodiment of the present application provides an intelligent transportation certificate authentication and revocation device, including:

[0052] An information initialization module, configured to generate a signature certificate to initialize the vehicle, obtain a vehicle registration certificate in combination with the signature certificate, and send it to the vehicle;

[0053] A pseudonym certificate generation module, configured to generate a pseudonym certificate for the vehicle by using the vehicle public key, the shuffling authority SA, and the pseudonym certificate authority PCA, and store the pseudonym certificate and then feedback it to the SA;

[0054] A proof generation module, configured to generate confirmation information for all received pseudonym certificates, insert the received pseudonym certificates into the database in the next update, and batch generate proofs for all pseudonym certificates;

[0055] An authentication revocation module, configured to obtain the pseudonym certificate and its proof and share information with the verification agency, where the verification agency authenticates the certificate and the proof, and shares the certificate and the proof with the vehicles within the communication range, and revokes the certificate of the malicious vehicle.

[0056] In the embodiment of the present application, pseudonym certificates are generated according to the registration certificate of the vehicle within the trusted network, and each pseudonym certificate corresponds to a proof, which not only protects the privacy of the vehicle, but also enables the correspondence of the vehicle. In the later verification of the vehicle, if it is found that the vehicle has malicious behavior, the registration certificate of the vehicle is pulled into the blacklist by revoking the pseudonym certificate, realizing the batch verification of vehicles within the communication area, and solving the problems of difficult vehicle identity verification, privacy leakage, and difficult revocation of malicious vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 is a schematic flowchart of an intelligent transportation certificate authentication and revocation method provided by an embodiment of the present application;

[0058] Figure 2Schematic diagram for initializing trust storage settings provided by an embodiment of the present application;

[0059] Figure 3 Schematic diagram for issuing a certificate for legal initialization of a vehicle provided by an embodiment of the present application;

[0060] Figure 4 Schematic diagram for registering a pseudonym certificate provided by an embodiment of the present application;

[0061] Figure 5 Schematic diagram for a typical network attack provided by an embodiment of the present application;

[0062] Figure 6 Schematic diagram for vehicle authentication and revocation provided by an embodiment of the present application;

[0063] Figure 7 Schematic diagram for a device for intelligent transportation certificate authentication and revocation provided by an embodiment of the present application. Detailed implementation manners

[0064] The following elaborates on this solution in conjunction with the accompanying drawings and the detailed implementation manners.

[0065] Refer to Figure 1 , the method for intelligent transportation certificate authentication and revocation in this embodiment includes:

[0066] S101, generating a signature certificate to initialize the vehicle, obtaining a vehicle registration certificate in combination with the signature certificate, and sending it to the vehicle.

[0067] As Figure 2 shown, this step mainly performs trust storage setting initialization and trust storage download of the device. First, the RCA (Root Certification Authority) is embedded in the blockchain after a group of trusted electors have strictly reviewed its security standards. Subsequently, the RCA will be authorized to sign the certificates of the ECA (Enrolment Certification Authority) and the PCA (Pseudonym Certification Authority) and insert them into the blockchain, and at the same time delegate the signing right to them. After successfully setting the trust storage, the vehicle will download the trust storage from the blockchain. Then the RCA generates a signature certificate for the trusted party and records it on the blockchain, and subsequently initializes the vehicle using the signature certificate. Finally, these vehicles can maintain a complete blockchain in the memory to act as full nodes, or only download the certificates or the hash values of the certificates from the blockchain to act as lightweight nodes.

[0068] As Figure 3, Subsequently, the vehicle sends a registration certificate signature request to the ECA in order to obtain a registration certificate. If the vehicle is initialized correctly, the ECA grants the registration certificate. At the same time, the ECA sends a logging request to the CDLM (Credential Distributed Ledger Maintainer) so that the registration certificate can be inserted into its database. After being inserted into the database, the registration certificate will be publicly available for public review and supervision.

[0069] S102, Generate a pseudonym certificate for the vehicle using the vehicle's public key, the shuffling mechanism SA, and the pseudonym certificate authority PCA, store the pseudonym certificate, and then feedback it to SA.

[0070] Generating the pseudonym certificate is the most complex part of this embodiment. The main reason is that it needs to protect the vehicle's true identity while ensuring the transparency and legality of the information flow at this stage. As Figure 4 shown, the message flow of the vehicle's pseudonym certificate issuance and registration.

[0071] First, the vehicle sends its public key to the shuffling mechanism SA. SA uses the butterfly key expansion method to generate a public key seed and sends the public key seed to the pseudonym certificate authority PCA for key signing.

[0072] Specifically, the vehicle generates a public key (a, A.g) and uses (a, A.g) to generate a pseudonym certificate signature request and forwards it to SA: ), where: Ecert is the vehicle's registration certificate, is the public key of the shuffling mechanism, is the vehicle's private key, is the signature function, is the encryption function. SA verifies that the vehicle's registration certificate has not been revoked and is the only pseudonym certificate signature request for this vehicle, then applies the vehicle's butterfly key expansion to generate n cocoon-shaped public keys. Otherwise, this step process ends.

[0073] SA mixes the extended public keys from different vehicles and forwards the message to PCA, , is the extended public key, is the public key of PCA, is the registration certificate, is the pseudonym certificate signature request, is the hash function.

[0074] Subsequently, PCA generates a pseudonym certificate for the vehicle using the signed public key seed, stores the pseudonym certificate in the CDLM, and at the same time sends the certificate to SA in ciphertext form.

[0075] Specifically, PCA generates a pseudonym certificate , where metainfo is metadata, is the digital signature secret identifier, , , where: ri is a random number, g is a generator, is the digital signature.

[0076] PCA sends the registration request message RegReq of the signed log to CDLM, , where: is the public key of CDLM.

[0077] CDLM returns the signature timestamp of the registration request to PCA , , where: t represents the current time, is the private key of CDLM.

[0078] PCA creates an encrypted package and returns it to SA, , where: is 's public key.

[0079] After SA accepts the said , it bundles for each vehicle for the vehicle to download. The vehicle downloads the bundled encrypted package and decrypts through the decryption algorithm to obtain , where: represents the private key for decrypting . Finally, SA executes and algorithms to verify the correctness of each pseudonym certificate and the corresponding , where is the verification function for verifying the digital signature.

[0080] As can be seen from the above process, SA provides the pseudonym certificate for the vehicle to download, but cannot extract the pseudonym certificate data from the encrypted package. At the same time, during the whole process of the vehicle obtaining the encrypted package, the pseudonym certificate guarantees the privacy of the vehicle. In addition, SA and PCA cannot correspond the issued pseudonym certificates to the registration certificates one by one. Finally, CDLM inserts a batch of pseudonym certificates in the next update.

[0081] S103, Generate confirmation information for all received pseudonym certificates, insert the received pseudonym certificates into the database in the next update, and generate proofs for all pseudonym certificates in batches.

[0082] As can be seen from S102, the SA provides the pseudonym certificate to the vehicle for downloading, but the pseudonym certificate data cannot be extracted from the encrypted package. Meanwhile, during the whole process of the vehicle obtaining the encrypted package, the pseudonym certificate ensures the privacy of the vehicle. In addition, the SA and the PCA cannot correspond the issued pseudonym certificates one by one with the registration certificates.

[0083] Therefore, in this embodiment, confirmation information is generated for all received pseudonym certificates, and the received pseudonym certificates are inserted into the database in the next update. Meanwhile, proofs are generated in batches for all pseudonym certificates. The update process is as follows: Let be the set of unexpired pseudonym certificates, then the new set of pseudonym certificates is , and the cumulative value is , , ,

[0084] , is the private key.

[0085] S104, obtain the pseudonym certificate and its proof and share the information with the verification agency. The verification agency authenticates the certificate and the proof, and shares the certificate and the proof with the vehicles within the communication range, and revokes the certificate for malicious vehicles.

[0086] After the pseudonym certificate Pcert is provided, each vehicle holds a set of Pcert. Once these pseudonym certificates Pcerts are inserted into the CDLM database, they generate validity proofs in batches for the pseudonym certificates within the communication range to prove the legality of these certificates. These proofs act as batch activation codes, simplifying the activation process. Compared with the CRL-based VPKI system, it can perform batch revocation status verification. The aggregator downloads the batch proofs of the pseudonym certificates and shares them with the edge server.

[0087] The edge server verifies the batch proofs and the corresponding pseudonym certificates received from the vehicles within the communication range. Then, the edge server generates a hash list of the pseudonym certificates in the communication proof and shares the hash list and the batch proofs with the vehicles within the communication range. The vehicle verifies the pseudonym certificate according to the hash list shared by the edge server. Finally, the vehicle caches the batch proof and verifies whether the Pcert is revoked according to the batch proof.

[0088] After aggregating the pseudonym certificates and the batch proofs, each vehicle has a set of pseudonym certificates and batch proofs generated by the CDLM. When a vehicle sends a signed message to another vehicle, the vehicle sends the message together with the signature certificate. The receiving vehicle verifies all the pseudonyms received from the vehicles within the communication range by checking whether the pseudonym is expired, whether it is signed by a trusted PCA, and whether it is revoked.

[0089] Hash the PCA certificate and compare the hash value with the PCA certificate hash value recorded on the blockchain to check whether the PCA certificate is recorded in the blockchain. This ensures that the public key PK of the PCA can effectively verify the pseudonym certificate. Subsequently, hash each pseudonym certificate and check whether the hash value of the pseudonym certificate exists in the hash list shared by the edge server. If the hash value of the pseudonym certificate matches the hash value in the list, the pseudonym certificate is accepted as a valid certificate. In addition, the pseudonym certificate is cached and verified

[0090] In this embodiment, it is necessary to ensure different levels of security. In the traditional VPKI, the security of the device depends on the security of the PCA. To change this situation, in this embodiment, the PCA is designed to forward content between the edge server and the CDLM, and a check mechanism is introduced between the PCA and the CDLM to ensure their honesty. In addition, the edge server is used to verify the pseudonym certificate, and the CDLM aggregates valid and unrevoked pseudonym certificates. During the aggregation process, any party can monitor whether the CDLM has malicious behavior

[0091] Therefore, the client in this embodiment needs to ensure honest behavior, and the CDLM needs to correctly update the ledger according to the pseudonym certificate registration requests they receive. These checks are performed by the edge server, aggregator, trusted centers (such as ECA, PCA, and RCA), vehicles, and RSUs to observe the correctness of the CDLM. Vehicles share the records of the CDLM obtained through the aggregator and verify them on the blockchain. Vehicles occasionally send a set of pseudonym certificates to the aggregator to check its status, while verifying the authenticity of the aggregator and the correctness of the CDLM records. In addition, vehicles need to randomly verify the logs, and if the verification is correct, the entire log will be verified. In short, any party can participate in supervising and identifying the malicious behavior of vehicles

[0092] When it is found that a vehicle is using an unexpired pseudonym certificate and exhibits malicious behavior, especially when there is a vehicle with a malicious attack, it is necessary to track the vehicle and the pseudonym certificate, associate the registration certificate with a set of pseudonym certificates, and add them to the blacklist. As Figure 5 shown, a vehicle enters an attack area from a safe area. Once it is successfully attacked by an attacker, the vehicle will become a tool for malicious attacks. As Figure 6 , in order to connect the registration certificate and the set of pseudonym certificates of the malicious vehicle, the edge server sends a hash value request to the PCA to map the pseudonym certificate to the PSR. Accordingly, the SA forwards the list of the registration certificate and the PSR hash value . The PCA further connects the set of pseudonym certificates to the list of PSR hash values and forwards them to the CDLM for revocation operation

[0093] In this embodiment, CDLM deletes them in the following manner: calculate the new cumulative value of the new list , and delete the set of pseudonym certificates belonging to malicious vehicles in the CDLM ledger: , where: L is the list of pseudonym certificates, is the list of pseudonym certificates to be deleted; deleting the pseudonym certificates from the CDLM database stops the use of malicious vehicles and adds them to the blacklist. The SA side retains the registration certificate and the corresponding hash value record, while the PCA only retains the mapping of the pseudonym certificates and the relevant hash values .

[0094] Corresponding to the intelligent transportation certificate authentication and revocation method provided in the above embodiment, the present application also provides an embodiment of an intelligent transportation certificate authentication and revocation device.

[0095] See Figure 7 , the intelligent transportation certificate authentication and revocation device 20 in this embodiment includes:

[0096] An information initialization module 201, configured to generate a signature certificate to initialize the vehicle, obtain a vehicle registration certificate in combination with the signature certificate, and send it to the vehicle;

[0097] A pseudonym certificate generation module 202, configured to generate a pseudonym certificate for the vehicle by using the vehicle public key, the shuffling authority SA, and the pseudonym certificate authority PCA, and store the pseudonym certificate and feedback it to the SA;

[0098] A proof generation module 203, configured to generate confirmation information for all received pseudonym certificates, insert the received pseudonym certificates into the database in the next update, and batch generate proofs for all pseudonym certificates;

[0099] An authentication revocation module 204, configured to obtain the pseudonym certificates and their proofs and share information with the verification authority, where the verification authority authenticates the certificates and proofs, and shares the certificates and proofs with the vehicles within the communication range to revoke the certificates of malicious vehicles.

[0100] For the same and similar parts among the various embodiments in the specification of the present application, reference can be made to each other. In particular, for the device embodiments, since the methods therein are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the descriptions in the method embodiments.

[0101] In the embodiments of the present application, "at least one" means one or more, and "a plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent the cases of A existing alone, A and B existing simultaneously, and B existing alone. Wherein A and B may be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. "At least one of the following" and its similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, and c may represent: a, b, c, a - b, a - c, b - c, or a - b - c, where a, b, and c may be single or multiple.

[0102] As described above, the foregoing is only the specific implementation manner of the present application. Any person skilled in the art within the technical scope disclosed in the present application can easily think of changes or substitutions, which should all be covered by the protection scope of the present application. The protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for authenticating and revoking an intelligent transportation certificate, characterized in that: include: Generate a signature certificate to initialize the vehicle and obtain a vehicle registration certificate in combination with the signature certificate and send it to the vehicle, including: Embed the root certificate authority RCA that meets trusted security standards into the blockchain; The RCA inserts the certificates of the registered certificate authorities ECA and PCA into the blockchain, and delegates the signing authority to the said ECA and PCA; The RCA generates a signed certificate for the trusted party and records it on the blockchain, and then uses the signed certificate to initialize the vehicle; The vehicle generates a public key and sends it to ECA for signing. ECA generates a vehicle registration certificate based on the signed certificate, registers it in the distributed ledger CDLM, and sends the registration certificate to the vehicle. Generate a pseudonym certificate for the vehicle using the vehicle public key, the shuffling agency SA and the pseudonym certificate agency PCA, and store the pseudonym certificate and then feed it back to SA, including: The vehicle sends the public key to the shuffling agency SA, which generates a public key seed using the butterfly key expansion method and sends the public key seed to the pseudonymous certificate authority PCA for key signing; PCA generates a pseudonym certificate for the vehicle using the signed public key seed, stores the pseudonym certificate in CDLM, and sends the pseudonym certificate to SA in ciphertext form; The vehicle sends the public key to the shuffling agency SA, which generates a public key seed using the butterfly key expansion method and sends the public key seed to the pseudonymous certificate authority PCA for key signing, including: The vehicle generates a public key (a, Ag) and uses the (a, Ag) to generate a pseudonymous certificate signing request Forward to SA: ), where: Ecert is the vehicle's registration certificate, is the public key of the shuffling agency, is the private key of the vehicle, is a signature function, is the encryption function; The SA verifies that the vehicle's registration certificate has not been revoked and that it is the only pseudonymous certificate signing request for the vehicle, and then uses butterfly key expansion to generate n cocoon-shaped public keys; The SA mixes the extended public keys from different vehicles and sends the message Forward to PCA, , is the extended public key, is the public key of PCA, is a registration certificate, is a pseudonymous certificate signing request, is a hash function; The PCA generates a pseudonym certificate for the vehicle using the signed public key seed, stores the pseudonym certificate in the CDLM, and sends the certificate to the SA in the form of ciphertext, including: PCA generates a pseudonym certificate , where metainfo is metadata, is the digital signature secret identifier, , , where: ri is a random number, g is a generator, It is a digital signature; PCA sends the signed log registration request message RegReq to CDLM. ,in: is the public key of CDLM; CDLM returns the signed timestamp of the registration request to PCA , , where: t represents the current time, is the private key of CDLM; PCA creates an encrypted packet And return to SA, ,in: yes 's public key; SA accepts the After that, bundle each vehicle , for vehicles to download; The vehicle downloads the bundled encrypted package and passes the decryption algorithm Decryption To obtain ,in: Decryption The private key of Final SA execution and algorithm to verify each pseudonym certificate and the corresponding Correctness, where is the verification function, used to verify the digital signature; Generate confirmation information for all received pseudonym certificates, and insert the received pseudonym certificates into the database in the next update, and generate proofs for all pseudonym certificates in batches, including: CDLM generates confirmation information for all received certificates, and inserts the received certificates into the database in the next update. The update process is as follows: Assume is a set of unexpired pseudonym certificates, then the new pseudonym certificate set is , the cumulative value is , , , , is the private key, L is the pseudonymous certificate list, is a list of pseudonymous certificates to be deleted; Obtain the pseudonymous certificate and its proof and share the information with the verification agency, the verification agency authenticates the certificate and proof, and shares the certificate and proof with vehicles within the communication range, and revokes the certificate of the malicious vehicle, including: The aggregator downloads the newly inserted pseudonymous certificate and its proof from the blockchain and CDLM and shares that information with the edge server; The edge server verifies the batch proofs and corresponding pseudonym certificates received from vehicles within the communication range; The edge server then generates a hash list of pseudonym certificates in the communication proof and shares the hash list and batch proof with vehicles within the communication range; The vehicle verifies the pseudonym certificate against the hash list shared by the edge server; The vehicle caches the batch certificate and verifies whether the pseudonym certificate has been revoked based on the batch certificate; When a vehicle is found to be using an unexpired pseudonym certificate and engaging in malicious behavior, the vehicle and pseudonym certificate are tracked, and the registration certificate is associated with the corresponding pseudonym certificate and blacklisted, including: The edge server sends the hash value to PCA Request to implement pseudonym certificate mapping to PSR; SA forwards the registration certificate and PSR hash value List of; PCA further concatenates the collection of pseudonymous certificates to the PSR hash value , and forwards them to CDLM for undo operations.

2. The intelligent traffic certificate authentication and revocation method according to claim 1, characterized in that: The vehicle verifies the pseudonym certificate based on the hash list shared by the edge server, including: Hash the PCA certificate and compare the hash value with the PCA certificate hash value recorded on the blockchain to check whether the PCA certificate is recorded in the blockchain; Each pseudonymous certificate is then hashed and checked for the presence of its hash value in a hash list shared by the edge server; if the hash value of the pseudonymous certificate matches a hash value in the list, the pseudonymous certificate is accepted as a valid certificate.

3. The intelligent traffic certificate authentication and revocation method according to claim 2, characterized in that: The PCA further concatenates the set of pseudonymous certificates to the PSR hash value , and forwards them to CDLM for undo operations, including: Compute the new list The new cumulative value of , deletes the pseudonymous certificate set belonging to the malicious vehicle in the CDLM ledger: , where: L is a list of pseudonym certificates, is a list of pseudonymous certificates to be deleted; Deleting the pseudonymous certificate from the CDLM database stops the malicious vehicle from being used and adds it to the blacklist; The SA side retains the registration certificate and the corresponding hash value records, while PCA only retains the pseudonymous certificate and the associated hash value 's mapping.

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