A multi-chain cross-regional vehicle network anonymous authentication and communication method and system

Abstract

The present invention belongs to the technical field of wireless communication networks, and more specifically, relates to a multi-chain cross-regional vehicle network anonymous authentication and communication method and system. The method includes S1, system initialization; S2, vehicle registration; S3, RSU registration; S4, cross-anonymous authentication and communication key negotiation between vehicles and RSU; S5, cross-anonymous authentication and communication key negotiation between vehicles; S6, update of temporary public keys. The system adopts a hierarchical and partitioned multi-chain blockchain structure, including a core layer and a management layer. The core layer adopts a private chain of blockchain technology as an information platform, and realizes distributed storage and synchronization of information between various TAs through the private chain; each area of ​​the management layer adopts the alliance chain in blockchain technology as an information platform. The present invention realizes a certificateless anonymous authentication scheme for vehicle network nodes, shortens the authentication delay, and reduces the number and complexity of authentication interactions.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communication networks, and more specifically, relates to a multi-chain cross-regional vehicle network anonymous authentication and communication method and system. Background Art

[0002] The Internet of Vehicles (IoV) is a typical intelligent transportation system that provides users with more convenient, safer, and smarter travel services. The IoV utilizes an open, mobile Ad Hoc network architecture that is decentralized, self-organizing, supports multi-hop forwarding, has fast node mobility, and places stringent latency requirements. Due to its unique network structure and wireless communication methods, IoV is vulnerable to various cyberattacks in practical applications. To protect the security and privacy of IoV communication entities, IoV entities and messages must be authenticated. This authentication also prevents the disclosure of vehicle location and other trajectory information. This means that communication and message authentication must also provide privacy protection.

[0003] In recent years, scholars have proposed numerous authentication protocols for the Internet of Vehicles (IoV). These protocols fall into several categories. Public Key Infrastructure (PKI)-based schemes require multiple certificates to conceal the vehicle's true identity to ensure anonymity. The extensive use of anonymous certificates complicates certificate management and revocation, requiring central authentication and potentially creating system bottlenecks. Identity-based cryptographic authentication schemes, for example, require the system key to be stored in the vehicle's tamper-proof device (TPD) to ensure anonymity. Keys are generated from the system key and the vehicle's pseudonym, and the pseudonym is used for identity verification. This achieves anonymity but requires the strong security of the TPD. Other schemes do not require a TPD, but require the publication of information or communication, requiring the participation of a third-party authentication authority to generate the vehicle's private key and pseudonym. This can easily create authentication bottlenecks when there are many vehicles in the network, which is inconsistent with the decentralized nature of the IoV. Blockchain technology can implement distributed data storage, peer-to-peer transmission, consensus mechanisms, and encryption algorithms. It is suitable for decentralized applications characterized by distributed consensus, particularly in complex road traffic environments where vehicles lack mutual trust.

[0004] There are also many blockchain-based Internet of Vehicles authentication schemes. Chinese patent document CN113596778A discloses an anonymous authentication method for Internet of Vehicles nodes based on blockchain. The authentication method includes the following steps: (1) system initialization; (2) LEA packages the vehicle registration request information and vehicle public key information into a generated transaction and uploads it to the blockchain network, and at the same time issues a certificate to the vehicle through the trusted center TA; (3) vehicle and roadside unit RSU authentication; (4) vehicle-to-vehicle authentication. Chinese patent document CN117041943A discloses a blockchain-based method for completely anonymous authentication and key agreement in the Internet of Vehicles (IoV). This method designs a pseudonym generation algorithm based on homomorphic encryption to ensure the verifiability of vehicle pseudonyms while achieving complete anonymity. Furthermore, a pseudonym automatic revocation mechanism is designed, which embeds a time-dependent secret value into the pseudonym and regularly updates the secret value to automatically revoke expired pseudonyms. Furthermore, the method uses decentralized blockchain technology to verify and store vehicle certificates, improving the efficiency of vehicle certificate authentication. This method not only achieves the verifiability and complete anonymity of vehicle pseudonyms, but also enables automatic pseudonym revocation, making it applicable to various authentication scenarios in the IoV environment. However, the above two methods still require the participation of multiple certificates, making the authentication process relatively complex.

[0005] Many existing solutions require vehicles to re-apply for private keys from a third-party authority each time they authenticate with a roadside unit (RSU) or infrastructure to ensure anonymity. This can lead to excessive communication interactions and authentication delays. This paper proposes a multi-chain, cross-region anonymous authentication and communication solution. This divides the Internet of Vehicles into multiple zones and uses multiple blockchains, including private and consortium chains, to achieve cross-region anonymous authentication and communication between vehicles and RSUs or infrastructure, and between vehicles.

[0006] In view of this, the present invention proposes a multi-chain, cross-regional vehicle network anonymous authentication and communication method to solve the problem that anonymous vehicle authentication requires frequent negotiation with a third party for private keys and certificates. Summary of the Invention

[0007] In response to the shortcomings of the existing technology, the purpose of the present invention is to disclose a multi-chain and cross-regional Internet of Vehicles anonymous authentication and communication method to realize a certificateless anonymous authentication scheme for Internet of Vehicles nodes. Vehicles can automatically update authentication private keys and public keys based on public parameters issued by a third-party authority, shortening the authentication delay and reducing the number and complexity of authentication interactions.

[0008] The present invention also discloses a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication system.

[0009] The detailed technical solutions adopted by the present invention to achieve the above-mentioned purpose are as follows:

[0010] A multi-chain cross-region vehicle network anonymous authentication and communication method, the method comprising the following steps:

[0011] S1, initialization of the Internet of Vehicles system;

[0012] S2. Vehicle registration;

[0013] S3, RSU registration;

[0014] S4, cross-vehicle anonymous authentication and communication key negotiation between the vehicle and RSU;

[0015] S5, cross-vehicle anonymous authentication and communication key negotiation;

[0016] S6. Update of temporary public key.

[0017] Preferably, according to the present invention, the initialization of the Internet of Vehicles system refers to selecting an elliptic curve on a finite field, constructing a cyclic additive group G on the elliptic curve, P is the generator of G, selecting a random number s as the master key of the system, calculating the system public key, calculating the key update parameters and the usage period of the key update parameters, and selecting 4 secure hash functions; then, the trusted center TA announces the system parameters, including the elliptic curve, the generator P, the system public key, the key update parameters and the usage period of the key update parameters, and the hash function, and writes the system parameters into the information registration chain of the core layer.

[0018] According to a preferred embodiment of the present invention, the vehicle registration includes the following steps:

[0019] S21. The vehicle submits registration information to the nearby trusted center TA through a secure channel, including the license plate number, owner information, vehicle ID, and area ID of the area to which it belongs;

[0020] S22. The trusted center TA server verifies the authenticity of the vehicle information. After the trusted center TA confirms the vehicle information is valid, the vehicle selects a random number, calculates the product of the random number and the generator P on the cyclic additive group G, and then sends the product value to the trusted center TA.

[0021] S23. The trusted center TA performs a one-way hash operation on the product value and the key update parameter to obtain the vehicle's key; the trusted center TA calculates multiple temporary public keys for the vehicle based on the multiple keys of the vehicle; the trusted center TA publishes the vehicle's registration information and multiple keys to the core layer's private chain information registration chain; the trusted center TA publishes the vehicle's multiple temporary public keys and the useful life of the temporary public keys to the global temporary public key chain of the private chain;

[0022] S24. The vehicle calculates multiple keys and multiple temporary public keys of the vehicle itself based on the system parameters and key update parameters published by the trusted center TA, and stores them securely.

[0023] Preferably, according to the present invention, the RSU registration includes the following steps:

[0024] S31. The RSU selects a random number and calculates the product of the random number and the generator P. The RSU sends the identity ID, area ID, and product value to the nearby trusted center TA for verification.

[0025] S32. After the trusted center TA verifies that the information is valid, the trusted center TA performs a one-way hash operation on the product value and the key update parameter to obtain the RSU's key. The trusted center TA calculates the RSU's public key based on the RSU's key, publishes the RSU's identity ID and area ID to the core layer's registration information chain, and publishes the RSU's public key and the public key's expiration date to the core's global temporary public key chain.

[0026] S33. The RSU calculates the vehicle's own key and public key based on the system parameters and key update parameters published by the trusted center TA, and stores them securely.

[0027] According to a preferred embodiment of the present invention, the cross-anonymous authentication and communication key negotiation between the vehicle and the RSU refers to that when the vehicle arrives at an area and needs to communicate with a nearby RSU, it specifically includes the following steps:

[0028] S41, RSU certified vehicles:

[0029] The vehicle selects a random number, combines the vehicle's real ID and the public key of the trusted center TA to calculate a pseudonym, selects a key to sign the pseudonym, the message M to be sent, and the current timestamp, and sends the signature and the public key corresponding to the key and the current timestamp to the RSU;

[0030] After receiving the message, the RSU checks whether the timestamp is within the validity period and uses the vehicle's public key to verify whether the signature equation is true. If so, it checks whether the vehicle and the RSU are in the same area:

[0031] If the vehicle and the RSU are in the same zone, check whether there is a public key for the vehicle in the alliance chain. If so, the vehicle is legal;

[0032] If the vehicle and the RSU are not in the same area, a query request is sent to the nearby trusted center TA. The trusted center TA queries the global temporary public key chain. If the vehicle's public key is available, the query result is symmetrically encrypted using the RSU's key and sent to the RSU. The RSU adds the vehicle's public key to the consortium chain where the RSU is located. If the vehicle needs authentication in the future, the RSU can directly query the consortium chain where the RSU is located without having to interact with the trusted center TA.

[0033] S42, Vehicle Certification RSU:

[0034] The RSU will use the key to sign the message to be sent and the current timestamp, and send the public key and the current timestamp to the outgoing vehicle. The vehicle verifies whether the timestamp is within the valid time. If so, it verifies whether the signature equation is established. If so, it checks whether the vehicle and the RSU are in the same area:

[0035] If the vehicle and the RSU are in the same zone, check whether the RSU's alliance chain has the RSU's public key. If so, the RSU is legal;

[0036] If the vehicle and the RSU are not in the same area, a query request is sent to the trusted center TA of the area to which the vehicle belongs. The trusted center TA queries the global temporary public key chain. If the RSU's public key is available, the query result is symmetrically encrypted with the vehicle's key and sent to the vehicle. The vehicle saves the RSU's public key locally.

[0037] S43. After the RSU is authenticated, the vehicle and RSU use their public keys to negotiate a communication key for secure data communication.

[0038] Preferably, according to the present invention, the specific steps of vehicle-to-vehicle anonymous authentication and communication key negotiation are as follows:

[0039] S51. When a vehicle arrives at an area and needs to send a message, the vehicle calculates a random number, calculates a pseudonym, and calculates a message signature using the pseudonym and a key of the vehicle. The signature includes the current timestamp and the signature, the vehicle's public key, and the current timestamp are sent to other vehicles.

[0040] S52. After receiving the message, other vehicles check whether the current timestamp is within the validity period. If the current timestamp has not expired, they verify whether the signature equation is established. If so, they access the RSU's alliance chain.

[0041] S53. If the consortium chain has the public key of the sending vehicle, the signature is valid, indicating that the current vehicle is legal. If the local consortium chain does not have the public key of the vehicle, and the receiving vehicle and the sending vehicle are not in the same region, the receiving vehicle sends a query request to the trusted center TA in the current region. The trusted center TA queries whether the vehicle public key exists through the global temporary public key chain and returns the query result to the vehicle. The vehicle receives the message and confirms whether the message signature is valid. If it is valid, it indicates that the current vehicle is legal.

[0042] S54. The other vehicle uses the same authentication method. After successful authentication, both parties calculate a shared key and use the shared key for data communication.

[0043] Preferably, according to the present invention, the updating of the temporary public key refers to:

[0044] The TA regularly publishes key update parameters and their expiration dates in the network. After receiving them, the vehicle or RSU calculates new public and private keys based on the key update parameters. The core layer's trusted center, the TA, updates the global temporary public key chain and the consortium chain in its region based on the key update parameters. Vehicles and RSUs in the network calculate their own public and private keys based on the key update parameters of the trusted center, the TA, and store them securely.

[0045] The vehicle has multiple public keys, and the public keys and private keys are dynamically updated. When the vehicle authenticates with the vehicle or the vehicle authenticates with the RSU, different private keys are used for signature and public key authentication. It is difficult for other nodes to track the vehicle based on the public key.

[0046] In another aspect of the present invention, a multi-chain, cross-regional Internet of Vehicles anonymous authentication and communication system is provided. The system adopts a layered, partitioned, multi-chain blockchain structure, including a core layer and a management layer. The core layer adopts a private chain of blockchain technology as an information platform, and realizes distributed storage and synchronization of information between various trusted centers TA through the private chain; each area of ​​the management layer adopts the alliance chain in blockchain technology as the information platform; the trusted center TA belongs to both the core layer and the management layer, and the trusted center TA needs to maintain information of the private chain and the alliance chain at the same time.

[0047] According to the preferred embodiment of the present invention, the core layer is composed of a trusted center TA and a server, which is used to complete the registration of vehicles and RSUs, the maintenance of real identity information of vehicles and RSUs, the maintenance of temporary public keys of vehicles and RSUs, and the generation and storage of secret parameters negotiated by vehicles and RSUs;

[0048] The management layer consists of a trusted center TA, RSUs, vehicles, and some edge nodes. The trusted center TA, RSUs, vehicles, and edge nodes are divided into regions according to their locations. Each region uses the alliance chain in blockchain technology as an information platform.

[0049] Preferably, the private chain includes two chains, one is a registration information chain, which is used to manage the registration information, identity information, keys negotiated between the vehicle and the trusted center TA, and keys negotiated between the RSU and the trusted center TA of the vehicle and RSU; the other is a global temporary public key chain, which is used to maintain the temporary public key and public key usage period of the vehicle and provide cross-domain services;

[0050] The alliance chain stores the temporary public keys of vehicles and RSUs and the usage period of the temporary public keys. Each region has a regional AID. In order to improve the maintenance efficiency of the alliance chain, the trusted center TA and RSU in the alliance chain maintain data. Vehicles can only access data and do not participate in the consensus mechanism. In the alliance chain, the trusted center TA is a full node of the blockchain, storing the temporary public keys and the usage period of temporary public keys of vehicles and RSUs in multiple regions. RSUs and edge nodes are partial nodes, mainly storing the temporary public keys and the usage period of temporary public keys of vehicles and RSUs in this region.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] (1) The vehicle of the present invention uses a pseudonym and the vehicle's temporary public key to send a message signature during the authentication process. Attackers and other nodes cannot calculate the vehicle's real ID through the pseudonym. The vehicle has multiple temporary public keys, and one of them is randomly selected each time a signature is made. In addition, the vehicle's temporary public key is updated regularly, so it is difficult for other attackers and vehicles to lock a vehicle using the pseudonym and temporary public key. The vehicle's authentication and communication are anonymous and unlinkable. During the vehicle authentication process, if the vehicle's message is abnormal, the trusted center TA can calculate the vehicle's real ID through the vehicle's pseudonym, thereby tracking the vehicle. Therefore, the authentication process also meets the traceability requirement.

[0053] (2) When the vehicle and RSU of the present invention perform cross-domain authentication and need to query the public key of the node in other domains, the RSU can assist in the query through the TA's global temporary public key chain and save the query result to the alliance chain of this area. In subsequent communications, there is no need to query again, which reduces the number of communications. When the vehicle and the vehicle cross authentication, it is necessary to verify whether the public key exists. The vehicle first queries the alliance chain of this area. If not, it sends a query request to the trusted center TA. The trusted center TA accesses the global temporary public key chain and returns the query result to the vehicle. The present invention can effectively realize the information security connection between the private chain and the alliance chain through the trusted center TA, improve the efficiency of authentication, and ensure the security of information. The private chain is composed of only the trusted center TA, which avoids single point failure and ensures the security of data. The alliance chain mainly stores the temporary public key information of the region. The RSU and some edge nodes participate in the consensus, and other network nodes can only query data. RSU and edge nodes are relatively few nodes in the region, and the data is maintained by a few nodes. In this way, the alliance chain has a high operating efficiency.

[0054] (3) The present invention does not use certificates, reducing the issuance and management costs of certificates. It ensures the reliability of authentication through temporary public keys. The public key update parameters are broadcasted in the Internet of Vehicles by TA, allowing each node to independently update the temporary public key. The implementation is simple, and it not only realizes the security properties of authentication such as anonymity and unlinkability, but also ensures the efficiency of authentication. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 This is a model diagram of a multi-chain, cross-regional Internet of Vehicles anonymous authentication and communication system of the present invention;

[0056] Figure 2 This is a process diagram of a multi-chain cross-region vehicle network anonymous authentication and communication method of the present invention;

[0057] Figure 3 This is a diagram of the mutual authentication and key negotiation process between the vehicle and the RSU of the present invention;

[0058] Figure 4 This is a diagram of the vehicle-to-vehicle cross-certification process of the present invention. DETAILED DESCRIPTION

[0059] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0060] Example 1

[0061] like Figure 2 As shown, the present invention provides a multi-chain cross-region vehicle network anonymous authentication and communication method and system, the method comprising the following steps:

[0062] S1, initialization of the Internet of Vehicles system;

[0063] S2. Vehicle registration;

[0064] S3, RSU registration;

[0065] S4, cross-vehicle anonymous authentication and communication key negotiation between the vehicle and RSU;

[0066] S5, cross-vehicle anonymous authentication and communication key negotiation;

[0067] S6. Update of temporary public key.

[0068] The initialization of the Internet of Vehicles system specifically refers to:

[0069] Given a security parameter k, TA selects a cyclic additive group {G, P, q}, generates a system key s, and calculates the public key P pub =sP, and define a secure hash function TA sends the system parameters {G, P, q, H0, H1, H2, H3} to the core layer blockchain. TA periodically selects a random number r and calculates P r = rP, (r,P r ,T expr ) as system parameters, where T expr It's P rAt the start and end time of network use, the TAs on the blockchain jointly maintain the system parameters.

[0070] The vehicle registration specifically refers to:

[0071] The vehicle provides the owner information, the real ID of the vehicle, the license plate number, the area identification AID of the area to which it belongs, etc. to apply for registration to TA through a secure channel. The vehicle selects k random numbers v t (t=1,2…k), calculate P t =v t P, P vt It is sent to TA through a secure channel, and TA selects the currently valid (r,P r ,T expr ), calculate multiple keys x between TA and vehicle t =H1(rP t ), calculate the vehicle temporary public key P vt =x t P. TA sends the vehicle owner information, the vehicle's real ID and the shared key x t Uploaded to a private chain registration information chain of the core layer, TA will transfer the temporary public key P vt and T expr Uploaded to another blockchain global temporary public key chain in the core layer, the global temporary public key chain mainly provides cross-certification services for vehicles. TA also uploads the temporary public key and public key usage period of the vehicle to the alliance chain of the management level where TA is located. r and T expr Sent to the vehicle via a secure channel. The vehicle calculates the shared key x vt =H1(v t P r ) and the temporary public key P vt =x t P and keep it safe.

[0072] The RSU registration specifically refers to:

[0073] Roadside Unit (RSU) j Choose a random number u j , calculate P uj =u j P, RSU will share its location information, identity information ID and area ID with P ui It is sent to TA through a secure channel. After TA verifies that the information is valid, TA selects the currently valid (r, P r ,T expr ) Calculate x uj =H1(rP uj ), P rsuj =x uj P, where x iis the key value shared by RSU and TA. TA takes RSU information and temporary key x uj Upload the registration information chain of the core layer and the temporary public key P rsuj and T expr Upload to the global temporary public key chain of the core layer and the alliance chain of the management layer. uj and T expr Sent to RSU, RSU calculates the temporary key x uj =H1(u j P r ) and the temporary public key P rsuj =x uj P and keep it safe.

[0074] The anonymous authentication and communication between the vehicle and the RSU specifically refers to:

[0075] like Figure 3 As shown, when the vehicle V m After arriving at an area, a message M needs to be sent, and the vehicle calculates and selects a random number w m , calculate pseudonyms Calculate the message signature δ = x t H2(PID m ,P w ,P xt ,M,AID i ,T exp )+w m , where x t (t=1,2…k) is one of the temporary keys chosen by the vehicle and negotiated with the TA, P w =w m P, P xt is the vehicle temporary shared key x t Corresponding temporary public key, AID m is the region ID where the vehicle is registered, T exp is the timestamp. The vehicle will (δ,PID m ,P w ,P xt ,M,AID m ) is sent to nearby RSUs.

[0076] After receiving the timestamp, the RSU checks whether it is within the validity period and verifies whether equation (1) holds:

[0077] δP=H2(PID m ,P w ,P xt ,M,AID m ,T exp )P xt +P w (1)

[0078] If the equality does not hold, the message is discarded. If the equality holds, and the AID m If it is in the same region as RSU, then check whether there is a temporary public key P in the alliance chain. xt , if there is P in the alliance chain xt , then the message signature is valid. If there is no P in the alliance chain xt , the signature is invalid.

[0079] If the equality holds, and AID m The RSU is not in the same area, and the RSU sends a query request to the TA in the same area (E xu (P xt ,RSU id ), RSU id ), E xu It is a symmetric encryption algorithm, xu is the original shared key between TA and RSU, RSU id is the identity ID of RSU, P xt is the vehicle temporary shared key x t The corresponding temporary public key. TA decrypts the shared key to obtain P xt , TA queries P in the global temporary public key chain of the core layer xt If so, then P xt and the public key usage period are added to the alliance chain of this area. And the query results are sent to H3(P xt ,true,xu),true is returned to RSU. After RSU receives the confirmation message from TA, it confirms that the message signature is valid. xt TA will H3(P xt ,false,xu),false is returned to RSU and the signature is invalid.

[0080] RSU chooses a random number w u , calculate P u =w u P, calculate signature

[0081] δ=x uj H2(PID m ,P u ,P rsu ,M,AID u ,T exp )+w u , where x uj Is the RSU key, PID m is the pseudonym of the other vehicle, P rsu is the public key of RSU, M is the message that RSU wants to send to the vehicle, AID uis the regional ID of the RSU, T exp is the current timestamp. RSU will sign the information (δ,PID m ,P u ,P rsu ,M,AID u ,T exp ) is sent to the vehicle, and the vehicle verifies whether equation (2) holds.

[0082] δP=H2(PID m ,P u ,P rsu ,M m ,AID u ,T exp )P rsu +P u (2)

[0083] If the equality holds, and AID u The vehicle is in the same area as the consortium chain in this area. The vehicle queries whether the consortium chain in this area has the public key of the RSU. If so, the signature is valid, otherwise the signature is invalid.

[0084] AID u If the vehicle is not in the same area, a random number w is selected. l , calculate the new pseudonym P l =w l P, sends a query request to the TA in the current area (E x (P rsu ,PID l ,P l ),PID l ,P l ), TA calculates RID m =PID l ⊕H1(sP l ), according to RID m Get the original shared key x between the vehicle and TA, E x It is a symmetric encryption algorithm. x (P rsu ,PID l ,P l ),PID l ,P l ) to obtain P rsu , TA queries P through the global temporary public key chain rsu If it exists, return E. x (P rsu ,true,PID l ), true for vehicle V m , and P rsuThe public key usage period is saved to the local alliance chain. rsu After the message exists, confirm that the message signature is valid. If P does not exist in the global temporary public key chain rsu , then return E x (P rsu ,false,PID l ),false to vehicle V m , the signature is invalid.

[0085] After both parties have successfully authenticated each other, they calculate the shared key.

[0086] The vehicle-to-vehicle anonymous authentication and communication specifically refers to:

[0087] like Figure 4 As shown, when the vehicle V m After arriving at an area, you need to send message M m , the vehicle calculates and selects a random number w m , calculate the pseudonymous PID m =RID m ⊕H(w m P pub ), calculate the message signature δ m =x t H2(PID m ,P w ,P xt ,M m ,AID m ,T exp )+w m , where x t is one of the temporary shared keys selected by the vehicle and negotiated with the TA, P w =w m P, P xt Is the vehicle temporary key x t Corresponding temporary public key, AID m is the region ID where the vehicle is registered, T exp is the timestamp. The vehicle will (δ m ,PID m ,P w ,P xt ,M m ,AID m ,T exp ) to other vehicles.

[0088] Other vehicles V l After receiving it, check whether the timestamp is within the validity period. If the timestamp is not expired, verify whether the equality is established:

[0089] δ m P=H2(PIDm ,P w ,P xt ,M m ,AID m ,T exp )P xt +P w (3)

[0090] If it is established, then access the alliance chain of the area where the vehicle belongs. If there is P xt , then the signature is valid. If the local alliance chain does not have P xt , and AID m and V l If it is not a region, a random number w is selected. l , calculate PID l =RID l ⊕H(w l P pub ),

[0091] P l =w l P, sends a query request to the TA in the current area (E x (P xt ,PID l ,P l ),PID l ,P l ), E x It is a symmetric encryption algorithm, the original shared key between vehicle x and TA. TA calculates RID l =PID l ⊕H(sP l ), according to RID l Get the original shared key x between the vehicle and TA, decrypt E x (P xt ,PID l ,P l ) to obtain P xt , query P through the global temporary public key chain xt If it exists, return E. x (P xt ,true,PID l ), true for vehicle V l , and P xt The public key and the usage period are added to the local consortium chain. After the vehicle receives the message confirming the existence of the public key, it confirms that the message signature is valid. If P does not exist in the global temporary public key chain, xt , then return E x (P xt ,false,PID l ),false to vehicle V l, the signature is invalid and the authentication fails.

[0092] The process of the other party's vehicle authenticating this vehicle is similar. After the authentication is successful, both parties calculate the shared key.

[0093] The updating of the temporary public key of the vehicle specifically refers to:

[0094] TA selects a new random number r' and calculates P r '=r'P,σ=sH3(P' r ,T exp )+r', broadcast (σ,P r ',T exp ) where T exp It's P r 'From the date of use to the expiration date, after the vehicle is received, verify whether equation (4) is true:

[0095] σP=H3(P' r ,T exp )P pub +P r ' (4)

[0096] If so, the vehicle uses the original shared key x i Calculate the new temporary shared key x i '=H1(x i P r '), new temporary public key P xi '=x i 'P.

[0097] TA uses the shared key x of the vehicle in the private chain's vehicle information chain i , calculate the new temporary shared key x i '=H1(x i P r '), calculate the temporary public key P xi '=x i 'P, and the temporary public key P xi '=x i 'P and the usage period of the temporary public key are uploaded to the alliance chain of this area, and the vehicle temporary public key and the usage period of the temporary public key are uploaded to the global temporary public key chain of the private chain.

[0098] Example 2

[0099] This embodiment provides a multi-chain cross-regional vehicle network anonymous authentication and communication system, which adopts a hierarchical partitioned multi-chain blockchain structure, such as Figure 1As shown in the figure, the core layer primarily consists of a highly secure trusted center (TA) and several high-performance servers. These centers primarily handle vehicle and RSU registration, maintain their real identities, maintain temporary public keys, and generate and store secret parameters negotiated between them. The core layer utilizes a private blockchain technology as its information platform. This private chain enables distributed information storage and synchronization between TAs. The core layer primarily maintains two chains: one manages vehicle and RSU registration information, identity information, and keys negotiated between the vehicle and TA, and between the RSU and TA. This chain is called the registration information chain. The other chain maintains temporary public keys for vehicles and provides cross-authentication services. This chain is called the global temporary public key chain. The management layer consists of TAs, RSUs, vehicles, and several edge nodes. TAs, RSUs, vehicles, and edge nodes are divided into zones based on location. Each zone utilizes a consortium chain, a blockchain technology-based information platform. The consortium chain primarily stores temporary public keys for vehicles and RSUs. Each zone has a zone AID. To improve consortium chain maintenance efficiency, TAs and RSUs maintain data within the consortium chain. Vehicles can only access data and do not participate in the consensus mechanism. TAs belong to both the core layer and the management layer, and they need to maintain information on both the private and consortium chains. In the consortium chain, TAs are full nodes of the blockchain, storing information such as temporary public keys for vehicles and RSUs in multiple regions. RSUs and edge nodes are partial nodes, primarily storing information such as temporary public keys for vehicles and RSUs in their respective regions.

[0100] When a vehicle and an RSU perform cross-domain authentication and need to query the public keys of nodes in other domains, the RSU can use the TA's global temporary public key chain to assist in the query and save the query results to the consortium chain in its own domain. Subsequent communications do not require re-querying, thus reducing communication times. When a vehicle authenticates across domains, it needs to verify the existence of a public key. The vehicle first queries the consortium chain in its own domain. If not, it sends a query request to the TA. The TA then accesses the global temporary public key chain and returns the query results to the vehicle. The vehicle and TA, as well as the RSU and TA, share a key. To prevent tampering with the query results, communication can use efficient symmetric key encryption. The original shared key is stored in the private chain's information registry. This invention effectively achieves information security integration between the private and consortium chains through the TA, improving authentication efficiency and ensuring information security. The private chain consists only of the trusted TA, avoiding single points of failure and ensuring data security. The consortium chain primarily stores the region's temporary public key information. The RSU and some edge nodes participate in consensus, while other network nodes can only query data. RSUs and edge nodes are relatively few in a region, and data maintenance by a small number of nodes ensures high operational efficiency of the consortium chain. Network nodes can query the public key, but cannot determine the vehicle's true identity from it, thus ensuring the anonymity of authentication. This solution does not use certificates, reducing the overhead of issuing and managing certificates. Instead, it uses temporary public keys to ensure the reliability of authentication. By issuing public key update parameters, each node can update its temporary public key independently. This simple implementation maintains the security properties of authentication, such as anonymity and unlinkability, while also ensuring high efficiency.

Claims

1. A multi-chain cross-regional vehicle network anonymous authentication and communication method, characterized in that: The method is applied to a multi-chain, cross-regional Internet of Vehicles anonymous authentication and communication system. The system adopts a hierarchical, partitioned, multi-chain blockchain structure, including a core layer and a management layer. The core layer consists of a trusted center (TA) and a server. The core layer uses a private chain of blockchain technology as an information platform, and realizes distributed storage and synchronization of information between various trusted centers (TA) through the private chain. The management layer consists of a trusted center (TA), a RSU, a vehicle, and some edge nodes. The trusted center (TA) and the RSU, the vehicle, and the edge nodes are divided into regions based on location. Each region of the management layer uses a consortium chain in blockchain technology as an information platform. The consortium chain stores temporary public keys of vehicles and RSUs in the region and the validity period of the temporary public keys. The trusted center (TA) belongs to both the core layer and the management layer, and needs to maintain information of both the private chain and the consortium chain. The multi-chain cross-region vehicle network anonymous authentication and communication method includes the following steps: S1, initialization of the Internet of Vehicles system; S2. Vehicle registration; The vehicle registration includes the following steps: S21. The vehicle submits registration information to the nearby trusted center TA through a secure channel, including the license plate number, owner information, vehicle ID, and area ID of the area to which it belongs; S22. The trusted center TA verifies the authenticity of the vehicle information. After the trusted center TA confirms the vehicle information is valid, the vehicle selects a random number, calculates the product of the random number and the generator P on the cyclic additive group G, and then sends the product value to the trusted center TA. S23. The trusted center TA performs a one-way hash operation on the product value and the key update parameter to obtain the vehicle's key; the trusted center TA calculates multiple temporary public keys for the vehicle based on the vehicle's multiple keys; the trusted center TA publishes the vehicle's registration information and multiple keys to the registration information chain of the core layer private chain; the trusted center TA publishes the vehicle's multiple temporary public keys and the useful life of the temporary public keys to the global temporary public key chain of the private chain; S24. The vehicle calculates its own multiple keys and multiple temporary public keys based on the system parameters and key update parameters published by the trusted center TA, and stores them securely. S3, RSU registration; S4, cross-domain anonymous authentication and communication key negotiation between vehicle and RSU; S5, cross-domain anonymous authentication and communication key negotiation between vehicles; S6. Update of temporary public key.

2. A multi-chain cross-regional vehicle network anonymous authentication and communication method according to claim 1, characterized in that: Initialization of the IoV system involves selecting an elliptic curve over a finite field, constructing a cyclic additive group G on the elliptic curve, where P is a generator of G, selecting a random number s as the system's master key, calculating the system's public key, calculating a key update parameter and its lifetime, and selecting four secure hash functions. Then, the trusted center TA publishes the system parameters, including the elliptic curve, generator P, system public key, key update parameters and the usage period of key update parameters, hash function, and writes the system parameters into the registration information chain of the core layer.

3. A multi-chain cross-regional vehicle network anonymous authentication and communication method according to claim 2, characterized in that: The RSU registration includes the following steps: S31. The RSU selects a random number and calculates the product of the random number and the generator P. The RSU sends the identity ID, area ID, and product value to the nearby trusted center TA for verification. S32. After the trusted center TA verifies that the information is valid, the trusted center TA performs a one-way hash operation on the product value and the key update parameter to obtain the RSU's key. The trusted center TA calculates the RSU's temporary public key based on the RSU's key, publishes the RSU's identity ID and area ID to the core layer's registration information chain, and publishes the RSU's temporary public key and the temporary public key's usage period to the core layer's global temporary public key chain. S33. RSU calculates its own key and temporary public key based on the system parameters and key update parameters published by the trusted center TA, and stores them securely.

4. A multi-chain cross-regional vehicle network anonymous authentication and communication method according to claim 1, characterized in that: The cross-domain anonymous authentication and communication key negotiation between the vehicle and the RSU refers to the following communication steps when the vehicle arrives at an area and needs to communicate with a nearby RSU: S41, RSU certified vehicles: The vehicle selects a random number, combines the vehicle's real ID and the public key of the trusted center TA to calculate a pseudonym, selects a key to sign the pseudonym, the message M to be sent, and the current timestamp, and sends the signature and the temporary public key corresponding to the key and the current timestamp to the RSU; After receiving the message, the RSU checks whether the timestamp is within the validity period and uses the vehicle's temporary public key to verify whether the signature equation is true. If so, it checks whether the vehicle and the RSU are in the same area: If the vehicle and the RSU are in the same zone, check whether there is a temporary public key for the vehicle in the alliance chain. If so, the vehicle is legal; If the vehicle and the RSU are not in the same area, a query request is sent to a nearby trusted center TA. The trusted center TA queries the global temporary public key chain. If the vehicle's temporary public key is available, the query result is symmetrically encrypted with the RSU's key and sent to the RSU. The RSU adds the vehicle's temporary public key to the consortium chain where the RSU is located. S42, Vehicle Certification RSU: The RSU uses the key to sign the message to be sent to the vehicle and the current timestamp, and sends the signature, temporary public key and current timestamp to the vehicle. The vehicle verifies whether the timestamp is within the valid time. If so, it verifies whether the signature equation holds. If so, it checks whether the vehicle and the RSU are in the same area: If the vehicle and the RSU are in the same area, check whether there is a temporary public key of the RSU in the RSU's alliance chain. If so, the RSU is legal; If the vehicle and the RSU are not in the same area, a query request is sent to the trusted center TA of the area to which the vehicle belongs. The trusted center TA queries the global temporary public key chain. If the RSU's temporary public key is available, the query result is symmetrically encrypted with the vehicle's key and sent to the vehicle. The vehicle saves the RSU's temporary public key locally. S43. After the RSU is authenticated, the vehicle and RSU use their public keys to negotiate a communication key for secure data communication.

5. The multi-chain cross-regional vehicle network anonymous authentication and communication method according to claim 1 is characterized in that: The specific steps of the vehicle-to-vehicle cross-domain anonymous authentication and communication key negotiation are as follows: S51. When a vehicle arrives at an area and needs to send a message, it selects a random number, calculates a pseudonym, and calculates a message signature using the pseudonym and a key of the vehicle. The signature includes the current timestamp, and the signature, the vehicle's temporary public key, and the current timestamp are sent to other vehicles. S52. After receiving the message, other vehicles check whether the current timestamp is within the validity period. If the current timestamp has not expired, they verify whether the signature equation is established. If so, they access the RSU's alliance chain. S53. If the consortium chain has the temporary public key of the sending vehicle, the signature is valid, indicating that the current vehicle is legal. If the local consortium chain does not have the temporary public key of the vehicle, and the receiving vehicle and the sending vehicle are not in the same region, the receiving vehicle sends a query request to the trusted center TA in the current region. The trusted center TA queries the global temporary public key chain for the existence of the vehicle's temporary public key and returns the query result to the vehicle. The vehicle receives the message and confirms whether the message signature is valid. If it is valid, it indicates that the current vehicle is legal. S54. The other vehicle uses the same authentication method. After successful authentication, both parties calculate a shared key and use the shared key for data communication.

6. A multi-chain cross-regional vehicle network anonymous authentication and communication method according to claim 1, characterized in that: The updating of the temporary public key refers to: TA regularly publishes key update parameters and the validity period of key update parameters in the network. After receiving them, the vehicle or RSU calculates new temporary public keys and private keys based on the key update parameters: the trusted center TA at the core layer updates the global temporary public key chain and the consortium chain in the region based on the key update parameters; the vehicles and RSU in the network calculate their own temporary public keys and private keys based on the key update parameters of the trusted center TA and save them securely.

7. A multi-chain cross-regional Internet of Vehicles anonymous authentication and communication system, characterized by: The system adopts a hierarchical, partitioned, multi-chain blockchain structure, including a core layer and a management layer. The core layer uses a private chain in blockchain technology as an information platform, and uses the private chain to achieve distributed storage and synchronization of information between various trusted centers (TAs). Each area in the management layer uses a consortium chain in blockchain technology as an information platform. The trusted center (TA) belongs to both the core layer and the management layer, and needs to maintain information on both the private chain and the consortium chain. The private chain includes two chains: one is the registration information chain, which is used to manage the registration information, identity information, and keys negotiated between the vehicle and the trusted center TA, as well as the keys negotiated between the RSU and the trusted center TA; the other is the global temporary public key chain, which is used to maintain the temporary public key of the vehicle and the temporary public key usage period, and provide cross-domain authentication services; the global temporary public key chain is also used to maintain the temporary public key of the RSU and the usage period of the temporary public key; The alliance chain stores the temporary public keys of vehicles and RSUs and the usage period of the temporary public keys. Each area has a regional AID. The trusted centers TA and RSU in the alliance chain maintain data. Vehicles can only access data and do not participate in the consensus mechanism. In the alliance chain, the trusted center TA is a full node of the blockchain, storing the temporary public keys and the usage period of the temporary public keys of vehicles and RSUs in this area. RSUs and edge nodes are partial nodes, mainly storing the temporary public keys and the usage period of the temporary public keys of vehicles and RSUs in this area.

8. The multi-chain cross-regional Internet of Vehicles anonymous authentication and communication system according to claim 7 is characterized in that: The core layer consists of a trusted center TA and a server, which is used to complete the registration of vehicles and RSUs, maintain the real identity information of vehicles and RSUs, maintain the temporary public keys of vehicles and RSUs, and generate and store the negotiated secret parameters of vehicles and RSUs; The management layer consists of a trusted center TA, RSUs, vehicles, and some edge nodes. The trusted center TA, RSUs, vehicles, and edge nodes are divided into regions according to their locations. Each region uses the alliance chain in blockchain technology as an information platform.

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