Multi-chain cross-region Internet of Vehicles anonymous authentication and communication method and system

Abstract

The invention belongs to the technical field of wireless communication networks, and more specifically relates to a multi-chain cross-region Internet of Vehicles anonymous authentication and communication method and system. The method comprises the following steps: S1, initializing a system; s2, vehicle registration; s3, RSU registration is carried out; s4, cross anonymous authentication and communication key negotiation between the vehicle and the RSU; s5, cross anonymous authentication and communication key negotiation between the vehicles; and S6, updating the temporary public key. The system adopts a layered, partitioned and multi-chain block chain structure and comprises a core layer and a management layer, the core layer adopts a private chain of a block chain technology as an information platform, and distributed storage and synchronization of information are realized among TAs through the private chain; and each region of the management layer adopts an alliance chain in the block chain technology as an information platform. According to the invention, a certificateless anonymous authentication scheme of the Internet of Vehicles node is realized, the authentication delay is shortened, and the number of interaction times and complexity of authentication are reduced.

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 Internet of Vehicles anonymous authentication and communication method and system. Background Art

[0002] The Internet of Vehicles is a typical intelligent transportation system that can provide users with more convenient, safer and smarter travel services. The network structure adopted by the Internet of Vehicles is an open mobile Ad Hoc network, which is decentralized, self-organized, supports multi-hop forwarding, has fast node movement speed and strict latency requirements. Due to the special network structure and wireless communication method of the Internet of Vehicles, it is easy to be attacked by various network attacks in practical applications. In order to protect the security and privacy of the communication entities of the Internet of Vehicles, it is necessary to authenticate the entities and messages of the Internet of Vehicles. At the same time, the location of the vehicle and other trajectory information must be prevented from being exposed. That is, communication or message authentication also needs to provide privacy protection functions.

[0003] In recent years, scholars have proposed many authentication protocols for the Internet of Vehicles, mainly in the following categories. In the scheme based on the public key infrastructure (PKI), in order to achieve the anonymity of authentication, multiple certificates are required to hide the real identity of the vehicle. The use of a large number of anonymous certificates will make the management and revocation of certificates complicated, and the management center needs to participate in the authentication, which is easy to form a bottleneck in the system. Identity-based password authentication schemes. In the identity-based Internet of Vehicles authentication schemes, many schemes need to store the system key in the vehicle's anti-tampering device TPD in order to ensure the anonymity of authentication. The key is generated by the system key and the vehicle's pseudonym, and the pseudonym is used when verifying the identity, achieving the anonymity of authentication, but requiring TPD to have strong security. There are also some schemes that do not require TPD, but these schemes require the release of information or communication, and require a third-party authentication agency to participate in generating the vehicle's private key and pseudonym. When there are many instantaneous vehicles, it is also easy to form an authentication bottleneck, which does not conform to the idea of ​​decentralization of the Internet of Vehicles. Blockchain technology can realize distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other mechanisms. It is suitable for decentralized application environments with distributed consensus characteristics, especially in complex road traffic environments where vehicles do not trust each other.

[0004] At present, there are also many Internet of Vehicles authentication schemes based on blockchain. 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 and vehicle authentication. Chinese patent document CN117041943A discloses a completely anonymous authentication and key negotiation method based on blockchain in the Internet of Vehicles. The method designs a pseudonym generation algorithm based on homomorphic encryption, which ensures the verifiability of the vehicle pseudonym while achieving the complete anonymity of the vehicle pseudonym; on this basis, a pseudonym automatic revocation mechanism is designed, a time-related secret value is embedded in the pseudonym, and the secret value is updated regularly to automatically revoke the expired pseudonym; in addition, the decentralized blockchain technology is used to verify and store vehicle certificates, which improves the authentication efficiency of vehicle certificates; the present invention not only achieves the verifiability and complete anonymity of the vehicle pseudonym, but also achieves the automatic revocation of the pseudonym, which can be used in various authentication scenarios in the Internet of Vehicles environment. However, the above two methods still require the participation of multiple certificates, and the authentication process is relatively complicated.

[0005] There are many other solutions. Every time a vehicle needs to authenticate with a roadside unit (RSU) or infrastructure, in order to ensure the anonymity of the authentication, it needs to re-apply for a private key from a third-party authority, resulting in too many communication interactions and authentication delays. This paper proposes a multi-chain cross-region anonymous authentication and communication solution, which divides the Internet of Vehicles into multiple regions and realizes cross-region anonymous authentication and communication between vehicles and roadside units (RSU) or infrastructure, and between vehicles through the joint work of private chains and alliance chains.

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

[0007] In view of the shortcomings of the prior art, 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 solution adopted by the present invention to achieve the above-mentioned purpose is as follows:

[0010] A multi-chain cross-regional Internet of Vehicles 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-anonymous authentication and communication key negotiation between vehicle and RSU;

[0015] S5, anonymous authentication and communication key negotiation between vehicles;

[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 publishes 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] Preferably, according to the present invention, the vehicle registration comprises 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 that 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 addition 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 key of the vehicle; the trusted center TA calculates multiple temporary public keys of the vehicle based on the multiple keys of the vehicle; the trusted center TA publishes the registration information of the vehicle and the multiple keys to the private chain information registration chain of the core layer; the trusted center TA publishes the multiple temporary public keys of the vehicle and the validity period 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 according to 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, RSU selects a random number, calculates the product of the random number and the generator P, and 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 registration information chain of the core layer, and publishes the RSU's public key and the public key's validity period to the core's global temporary public key chain.

[0026] S33. 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] Preferably, 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, calculates a pseudonym based on the vehicle's real ID and the public key of the trusted center TA, selects a key pair 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 it, the RSU checks whether the timestamp is within the validity period and uses the vehicle's public key to verify whether the signature equation holds. 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 area, check whether there is a public key of 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 Authentication 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 holds. 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 area, check whether there is a public key of the RSU in the RSU's alliance chain. 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 there is the public key of the RSU, the query result is symmetrically encrypted with the vehicle's key and sent to the vehicle. The vehicle saves the public key of the RSU locally.

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

[0038] Preferably, according to the present invention, the specific steps of cross-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 and selects a random number, calculates a pseudonym, and calculates a message signature using the pseudonym and a key of the vehicle. The signature contains 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 is not expired, the other vehicles verify whether the signature equation is established. If so, the other vehicles access the alliance chain of the RSU.

[0041] S53. If the alliance chain has the public key of the sender's vehicle, the signature is valid, indicating that the current vehicle is legal; if the local alliance 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, and 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 method for authentication. 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] 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 public and private keys based on the key update parameters: the core layer's trusted center TA updates the global temporary public key chain and the alliance chain in the region based on the key update parameters; the vehicles and RSUs in the network calculate their own public and private keys based on the key update parameters of the trusted center 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 other vehicles 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 an information platform; the trusted center TA belongs to the core layer and also exists in the management layer, and the trusted center TA needs to maintain the information of the private chain and the alliance chain at the same time.

[0047] Preferably, according to 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 vehicle and RSU negotiated secret parameters;

[0048] The management layer is composed of a trusted center TA, RSU, vehicles, and some edge nodes. The trusted center TA, RSU, vehicles, and edge nodes are divided into regions according to location, and 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 the 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 the data. Vehicles can only access the 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 multiple regions. RSU 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 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, one of which is randomly selected for each signature, and the vehicle's temporary public key is updated regularly. Therefore, 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, so 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 global temporary public key chain of TA, 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, so that the alliance chain has a high operating efficiency.

[0054] (3) The present invention does not use certificates, thus reducing the overhead of issuing and managing certificates. The reliability of authentication is ensured by a temporary public key. The public key update parameters are broadcasted by TA in the Internet of Vehicles, allowing each node to independently update the temporary public key. The implementation is simple, and it not only realizes the security attributes 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-regional Internet of Vehicles 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 It is a diagram of the cross-vehicle authentication process of the present invention. DETAILED DESCRIPTION

[0059] The present disclosure is further described below in conjunction with the accompanying drawings and embodiments.

[0060] Embodiment 1,

[0061] like Figure 2 As shown, the present invention provides a multi-chain cross-regional Internet of Vehicles 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-anonymous authentication and communication key negotiation between vehicle and RSU;

[0066] S5, anonymous authentication and communication key negotiation between vehicles;

[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 sets the system parameters {G,P,q,H 0 ,H 1 ,H 2 ,H 3} is sent 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 YesP r At 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 regional 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 the vehicle t =H 1 (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 the 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 =H 1 (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 i is the key value shared by RSU and TA. TA sends RSU information and temporary key x uj Upload the registration information chain of the core layer and the temporary public key P of RSU 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 temporary key x uj =H 1 (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 H 2 (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 selected by the vehicle and negotiated with the TA, P w =w m P,P xt is the vehicle temporary shared key x t The 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=H 2 (PIDm ,P w ,P xt ,M,AID m ,T exp ) xt +P w (1)

[0078] If the equality does not hold, the message is discarded. If the equality holds, and the AID m If the RSU is in the same region, 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 equation holds, and AID m The RSU is not in the same area, so 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 RSU ID, 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 yes, 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 H 3 (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 H 3 (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 H 2 (PID m ,P u ,P rsu ,M,AIDu ,T exp )+w u , where x uj is the key of RSU, PID m is the pseudonym of the other vehicle, P rsu is the public key of the RSU, M is the message that the RSU wants to send to the vehicle, and AID u is 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=H 2 (PID m ,P u ,P rsu ,M m ,AID u ,T exp ) rsu +P u (2)

[0083] If the equation 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 and the vehicle are not in the same area, then 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 ⊕H 1 (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. TA decryption (E x (P rsu ,PID l ,P l ),PID l,P l ) to get 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 rsu The public key and the expiration date are saved in the local consortium 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 the vehicle V m , the signature is invalid.

[0085] After both parties have successfully authenticated each other, a shared key is calculated.

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

[0087] like Figure 4 As shown, when the vehicle V m After reaching an area, you need to send a 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 H 2 (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 The 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 VehiclesV l After receiving it, check whether the timestamp is within the validity period. If the timestamp is not expired, verify whether the equation holds:

[0089] δ m P=H 2 (PID m ,P w ,P xt ,M m ,AID m ,T exp ) xt +P w (3)

[0090] If it is established, then access the consortium chain of the area where the vehicle belongs. If there is P xt , then the signature is valid. If the local consortium 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, vehicle x and TA share the original key. 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 get 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 public key 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 the vehicle V l , the signature is invalid and 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=sH 3 (P' r ,T exp )+r', broadcast (σ,P r ',T exp ) where T exp YesP r 'From the date of use to the expiration date, after the vehicle is received, verify whether equation (4) is true:

[0095] σP=H 3 (P' r ,T exp ) pub +P r ' (4)

[0096] If so, the vehicle uses the original shared key x i Calculate a new temporary shared key x i '=H 1 (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 '=H 1 (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 temporary public key usage period are uploaded to the alliance chain of this area, and the vehicle temporary public key and the temporary public key usage period are uploaded to the global temporary public key chain of the private chain.

[0098] Embodiment 2,

[0099] This embodiment provides a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication system, the system adopts a hierarchical partitioned multi-chain blockchain structure, such as Figure 1 As shown in the figure, the core layer mainly consists of a trusted center TA with very high security performance and some high-performance servers, which mainly complete the registration of vehicles and RSUs, the maintenance of the 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. The core layer uses the private chain of blockchain technology as the information platform. The distributed storage and synchronization of information between various TAs are realized through the private chain. The core layer mainly maintains two chains. One chain manages the registration information, identity information and keys negotiated between vehicles and TAs, and keys negotiated between RSUs and TAs. This chain is called the registration information chain. The other chain maintains the temporary public key of the vehicle and provides cross-authentication services. It is called the global temporary public key chain. The management layer consists of TA, RSU, vehicles and some edge nodes. TA, RSU, vehicles and edge nodes are divided into regions according to their locations. Each region uses the alliance chain in blockchain technology as the information platform. The alliance chain stores the temporary public keys of the main vehicles and RSUs. Each region has a regional AID. In order to improve the maintenance efficiency of the alliance chain, TA and RSU in the alliance chain maintain data, and vehicles can only access data and do not participate in the consensus mechanism. TA belongs to both the core layer and the management layer, and TA needs to maintain the information of the private chain and the alliance chain at the same time. In the alliance chain, TA is a full node of the blockchain, which can store temporary public keys and other information of vehicles and RSUs in multiple regions. RSUs and edge nodes are partial nodes, mainly storing temporary public keys and other information of vehicles and RSUs in this region.

[0100] When the vehicle and RSU perform cross-domain authentication and need to query the public key of the node in other domains, the RSU can assist the query through the global temporary public key chain of TA 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 there is no query request sent to TA, TA accesses the global temporary public key chain and returns the query result to the vehicle. The vehicle and TA, RSU and TA have a shared key. In order to prevent the query result from being tampered with, the communication can use efficient symmetric key encryption communication. The original shared key is stored in the information registration chain of the private chain. The present invention can effectively realize the information security connection between the private chain and the alliance chain through TA, improve the efficiency of authentication, and ensure the security of information. The private chain is composed of only the trusted node 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 data is maintained by a few nodes, so that the alliance chain has a high operating efficiency. Network nodes can query the public key, but cannot know the real identity of the vehicle from the public key, thus ensuring the anonymity of authentication. This solution does not use certificates, reducing the overhead of issuing and managing certificates. It uses temporary public keys to ensure the reliability of authentication. By issuing public key update parameters, each node can update the temporary public key by itself. The implementation is simple, which not only realizes the security attributes of authentication such as anonymity and unlinkability, but also ensures the efficiency of authentication.

Claims

1. A multi-chain cross-regional Internet of Vehicles anonymous authentication and communication method, characterized in that: The method comprises the following steps: S1, initialization of the Internet of Vehicles system; S2. Vehicle registration; S3, RSU registration; S4, cross-anonymous authentication and communication key negotiation between vehicle and RSU; S5, anonymous authentication and communication key negotiation between vehicles; S6. Update of temporary public key.

2. According to claim 1, a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication method is characterized in that: The initialization of the Internet of Vehicles system refers to selecting an elliptic curve on a finite field, constructing a cyclic addition group G on the elliptic curve, where P is a generator of G, selecting a random number s as a master key of the system, calculating a system public key, calculating a key update parameter and a usage period of the key update parameter, 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 validity period of the key update parameters, and hash function, and writes the system parameters into the information registration chain of the core layer.

3. According to claim 1, a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication method is characterized in that: The vehicle registration comprises 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 server verifies the authenticity of the vehicle information. After the trusted center TA confirms that 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 addition 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 key of the vehicle; the trusted center TA calculates multiple temporary public keys of the vehicle based on the multiple keys of the vehicle; the trusted center TA publishes the registration information of the vehicle and the multiple keys to the private chain information registration chain of the core layer; the trusted center TA publishes the multiple temporary public keys of the vehicle and the validity period of the temporary public keys to the global temporary public key chain of the private chain; S24. The vehicle calculates multiple keys and multiple temporary public keys of the vehicle itself according to the system parameters and key update parameters published by the trusted center TA, and stores them securely.

4. According to claim 1, a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication method is characterized in that: The RSU registration includes the following steps: S31, RSU selects a random number, calculates the product of the random number and the generator P, and 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 public key based on the RSU's key, publishes the RSU's identity ID and area ID to the registration information chain of the core layer, and publishes the RSU's public key and the public key's validity period to the core's global temporary public key chain. S33. 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.

5. According to claim 1, a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication method is characterized in that: 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: S41, RSU certified vehicles: The vehicle selects a random number, calculates a pseudonym based on the vehicle's real ID and the public key of the trusted center TA, selects a key pair 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; After receiving it, the RSU checks whether the timestamp is within the validity period and uses the vehicle's public key to verify 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 public key of 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 the nearby trusted center TA. The trusted center TA queries the global temporary public key chain. If there is a public key of the vehicle, the query result is symmetrically encrypted with the RSU's key and sent to the RSU. The RSU adds the vehicle's public key to the alliance chain where the RSU is located. S42, Vehicle Authentication RSU: 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 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 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 there is the public key of the RSU, the query result is symmetrically encrypted with the vehicle's key and sent to the vehicle. The vehicle saves the public key of the RSU locally. S43. After the RSU is authenticated, the vehicle and the RSU use their public keys to negotiate the communication key and conduct secure data communication.

6. According to claim 1, a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication method is characterized in that: The specific steps of cross-vehicle anonymous authentication and communication key negotiation are as follows: S51. When a vehicle arrives at an area and needs to send a message, the vehicle calculates and selects a random number, calculates a pseudonym, and calculates a message signature using the pseudonym and a key of the vehicle. The signature contains the current timestamp, and the signature, the vehicle's 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 is not expired, the other vehicles verify whether the signature equation is established. If so, the other vehicles access the alliance chain of the RSU. S53. If the alliance chain has the public key of the sender's vehicle, the signature is valid, indicating that the current vehicle is legal; if the local alliance 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, and 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; S54. The other vehicle uses the same method for authentication. After successful authentication, both parties calculate a shared key and use the shared key for data communication.

7. According to claim 1, a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication method is 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 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 alliance chain in the area according to the key update parameters; the vehicles and RSUs in the network calculate their own public keys and private keys according to the key update parameters of the trusted center TA and keep them safely.

8. A multi-chain cross-regional Internet of Vehicles anonymous authentication and communication system, characterized in that: The system adopts a hierarchical and partitioned multi-chain blockchain structure, including a core layer and a management layer. The core layer adopts the 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 the core layer and also exists in the management layer, and the trusted center TA needs to maintain the information of the private chain and the alliance chain at the same time.

9. A multi-chain cross-regional Internet of Vehicles anonymous authentication and communication system according to claim 8, characterized in that: 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; The management layer is composed of a trusted center TA, RSU, vehicles, and some edge nodes. The trusted center TA, RSU, vehicles, and edge nodes are divided into regions according to location, and each region uses the alliance chain in blockchain technology as an information platform.

10. According to claim 8, a multi-chain cross-regional Internet of Vehicles anonymous authentication and communication system is characterized in that: The private chain includes two chains, one is a registration information chain, which is used to manage the registration information, identity information, key negotiated between the vehicle and the trusted center TA, and key 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-certification services; The alliance chain stores the temporary public keys of vehicles and RSUs and the validity period of the temporary public keys. Each region 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 validity period of the 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 validity period of the temporary public keys of vehicles and RSUs in this region.

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