A cross-domain authentication method and system in a vehicle-mounted ad hoc network
Through the cross-domain authentication method under the vehicle-mounted ad hoc network, using the key generation center, trusted authorization agency and blockchain technology, a threshold group signature and revocation mechanism is constructed, which solves the trust and security challenges of the vehicle network system in cross-domain communication and realizes efficient and secure cross-domain authentication and user identity management.
Patent Information
- Application Number
- CN202411424376.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-12
- Publication Date
- 2025-09-19
- Estimated Expiration
- 2044-10-12
AI Technical Summary
There are inter-domain distrust and operability issues in the cross-domain communication process of the Internet of Vehicles system. Traditional authentication methods increase the load on the authentication center, single-node servers are vulnerable to attacks, and the risk of user privacy leakage is high. In addition, traditional authentication methods cannot effectively respond to complex security challenges.
A cross-domain authentication method under the vehicle-mounted ad hoc network is adopted. A threshold group signature is constructed through the key generation center, trusted authorization agency, roadside unit and vehicle. Combined with blockchain technology, cross-domain identity authentication and illegal user identification are realized. Intra-domain private chain and inter-domain alliance chain are used to eliminate the problem of distrust. Non-interactive zero-knowledge proof is used for identity authentication, and malicious users are handled through a tree structure revocation mechanism.
It achieves efficient, secure and reliable cross-domain authentication without leaking user privacy, reduces system storage redundancy, ensures the long-term safe and stable operation of the blockchain network, monitors and identifies malicious users in real time, and eliminates trust barriers between domains.
Smart Images
Figure CN119300037B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of network security communication technology, and in particular to a cross-domain authentication method in a vehicle-mounted ad hoc network. Background Art
[0002] With the continuous development of mobile communication networks and autonomous driving technologies, Internet of Vehicles (IoV) technology, with its unique features and applications, has significantly improved road traffic safety and efficiency, and is gradually becoming one of the areas with the greatest industrial potential. However, with the large-scale deployment of Internet of Vehicles (IoV) networks, users face a series of threats to information security and privacy. To ensure and improve the security of IoV user data interaction, IoV systems must improve the efficiency of vehicle communication and rapid data collection.
[0003] The communication environment of the Internet of Vehicles (IoV) is inherently vulnerable due to its use of public wireless communication technologies. The high mobility of vehicles and the volatile environment increase the risk of malicious attacks during communications. Malicious attackers can intercept and eavesdrop on messages in transit and perform various security attacks, including modification, identity forgery, spoofing, or replaying these messages. This not only threatens data integrity and confidentiality but also potentially leads to traffic accidents.
[0004] During cross-domain communication, devices in different domains often rely on independent authentication mechanisms. This diverse authentication system can lead to inter-domain distrust and interoperability issues during cross-domain interactions, exacerbating security challenges in protecting data privacy and identity. Furthermore, the complexity of cross-domain communication further amplifies the risk of user privacy breaches and places higher demands on robust and secure identity authentication. These factors collectively constitute key challenges in cross-domain authentication for the Internet of Vehicles. Traditional authentication methods increase the workload of authentication centers, and single-node servers face the risk of service disruption in the event of failure or attack.
[0005] In summary, the Internet of Vehicles system requires a new authentication solution that can achieve efficient, secure, and reliable cross-domain authentication while protecting user privacy, so as to cope with the complex security challenges in the IoV environment. Summary of the Invention
[0006] In view of the technical problems in the prior art, the present invention provides a cross-domain authentication method and system in a vehicle-mounted ad hoc network.
[0007] In a first aspect, the present invention provides a cross-domain authentication method in a vehicle-mounted ad hoc network. The method is implemented based on a cross-domain authentication system in the vehicle-mounted ad hoc network. The cross-domain authentication system includes a key generation center, a trusted authority in at least one domain corresponding to each area, and a plurality of roadside units and vehicles in each area. The method includes the following steps:
[0008] System initialization: the trusted authority generates system parameters within the domain;
[0009] Vehicle initialization: The trusted authority generates a pseudo-identity for the vehicle based on the system parameters within the domain and sends it to the vehicle via a secure channel. The vehicle verifies the pseudo-identity, obtains the corresponding public key and private key, and stores them.
[0010] Roadside unit initialization: the trusted authority generates a key message for the roadside unit based on the system parameters in the domain and sends it to the corresponding roadside unit through a secure channel. The roadside unit verifies the key message, obtains the corresponding key, and stores it;
[0011] Constructing a threshold group signature: Constructing a threshold group, which is composed of several vehicles and roadside units as members; any vehicle in the threshold group generates a signature for a traffic message and broadcasts it, and the roadside unit or other vehicles receive the signed message and verify whether the signature is legitimate;
[0012] Identity update: Before performing intra-domain identity authentication, the trusted authority updates the user's identity by calling the update algorithm;
[0013] Intra-domain identity authentication: A trusted authority within the domain authenticates the vehicle's identity. After successful authentication, the vehicle establishes a communication connection with other vehicles within the domain.
[0014] Inter-domain identity authentication: A vehicle in the first domain initiates an inter-domain connection request, which is forwarded by a trusted authority in the first domain. The trusted authority in the second domain performs identity authentication. If the authentication succeeds, the vehicle in the first domain establishes a communication connection with the vehicle in the second domain.
[0015] Identify illegal users: The trusted authorization agency authenticates users within the domain and identifies illegal users;
[0016] Deregistering illegal users: The trusted authorization agency establishes a revocation tree on the blockchain. When an illegal user exists, the trusted authorization agency deregisters the registration information of the illegal user.
[0017] Furthermore, system initialization includes:
[0018] Let F P represents a finite field of order p, over which the trusted authority constructs an elliptic curve E;
[0019] Choose a generator P from E, a cyclic group G of order large prime number q;
[0020] The trusted authority randomly selects As the private key SK GA , the public key is obtained by calculation is a finite field;
[0021] Defining a secure hash function The common system parameters are {G,q,P,P pub ,H0,H1,H2},P pub is the system public key;
[0022] The vehicle initialization includes:
[0023] The vehicle generates a random number Calculate K i =k i P, then sends a registration request {Register||ID i ,K i ,t i}, where ID i It is a vehicle i The real identity information, t i Indicates the current timestamp of the registration request;
[0024] The trusted authority selects a random number Calculating pseudonyms R i =r i P,h0=H0(PID i ,K i ,R i ),as well as s n is the system private key;
[0025] Generate identity certificate cert i =(Acc i ||ID i ||PID i ||gpk||t i ||T i ); Acc i is a blockchain account, gpk is a vehicle i The group public key of the domain, T i It is cert i validity period;
[0026] Generate pseudo-identity message {Response||cert i ||y i ||R i} and sent to the vehicle through a secure channel i ;
[0027] The vehicle i By calculating y i P=R i +H0(PID i ,K i ,R i )P pub , verify the pseudo identity; if the verification is successful, then (cert i ,K i ,k i ,R i ,y i ) is stored on the blockchain within the domain, and the public key and private key of the vehicle are vpk i =K i , vsk i =k i ;
[0028] The roadside unit initialization includes:
[0029] The roadside unit generates a random number Calculate K j =k j P, and get the current time T j ∈{0,1} * , the message {Register||ID j ,K j ,T j} is sent to the trusted authority; wherein, ID j is the identity information of the roadside unit;
[0030] After receiving the message, the trusted authority generates a random number Calculate R j =r j P, h1=H1(ID j ,K j )as well as
[0031] Generate key message {Response||gpk,R j ,y j ,T j}, and sent to the roadside unit via a secure channel;
[0032] The roadside unit is calculated by Verify the key message; if the verification is successful, {k j ,K j ,r j ,R j} is stored on the blockchain within the domain; the public key and private key of the roadside unit are vpk j =K j , vsk j =k j .
[0033] Furthermore, the construction threshold group includes:
[0034] A threshold group signature scheme of (t,n) is used, where t is the threshold value and the threshold group is a set consisting of n members, represented by M={m1,m2,…,m t}(t≤n); The members of the threshold group include at least: group administrator GA, group member m i , signature verifier GV, θ is the traffic message that needs to be signed;
[0035] The group administrator GA randomly selects a secret value And calculate pk i =κ i P, where κ i =sk i ; Then secretly select a polynomial of degree t-1 where a iz ∈[1,p-1](z=0,1,…,t-1);
[0036] Calculate the group private key of the threshold group as sk gi =f i (0) = a i0 , calculate the public key of the threshold group as pk gi =f i (0)P=a i0 P;
[0037] Group member m i Randomly choose a secret value Calculate pk i =ν i P, and generate a temporary pseudonym ζ i ;
[0038] Any of the vehicles in the threshold group generates a signature of a traffic message and broadcasts the signature, including:
[0039] Group member m i Through the private key sk i Sign traffic messages i =sk i I i +h i (θ)ν i modp, where h i (θ) is the hash value of the traffic message;
[0040] Group member m i Broadcasting the signature of the traffic message;
[0041] The roadside unit or other vehicle receives the signed message and verifies whether the signature is legitimate, including:
[0042] Single message authentication: via public user pseudonym PID i Computation I i And the hash value h of the traffic message i (θ), and by calculating ν i h i (θ)=s i P-pk i I i To verify whether the signature is legitimate;
[0043] And / or, batch message verification: When the group administrator GA receives N different signed messages, it calculates and verification message The threshold signature (S, V) and verification message Y are broadcast to the signature verifier GV in the group. When N ≥ t, SP is calculated to verify whether the signature is legal; where:
[0044]
[0045] Furthermore, identity updates include:
[0046] Vehicle inspection identity certificate cert i Whether it is expired, if so, submitting an update request {IDUpData} to the trusted authority through the roadside unit;
[0047] The trusted authority calls the update algorithm to complete the identity update of the vehicle;
[0048] The roadside unit submits the user's blockchain account Acc to the trusted authority i , group public key gpk and T i Perform identity updates;
[0049] The trusted authority verifies the validity of the signature through gpk. If it is valid, Time = T i new ;
[0050] Output T i new , gpk updates user identity information.
[0051] Furthermore, the intra-domain identity authentication includes:
[0052] The vehicle will send its identity certificate i Send to the current roadside unit via a secure channel;
[0053] After receiving the T i If valid, the consistency of the group public key gpk is verified. If they are the same, the authentication is successful.
[0054] Establishing a communication connection between the first vehicle and another second vehicle in the domain, the process includes:
[0055] The first vehicle uses the private key vsk i Sign the request message And send a request to establish communication to the second vehicle through the secure channel {request||σ i};
[0056] After the second vehicle receives it, j Extract the group public key gpk and verify the signature. If the verification is successful, it proves that the two belong to the same domain.
[0057] The second vehicle uses the private key vsk j Sign the response message And send a response to the communication request {response||σ j};
[0058] After the first vehicle receives the identity certificate i Extract the group public key gpk pair σ j Verification is performed, and if the verification is successful, a communication connection is established between the first vehicle and the second vehicle.
[0059] Furthermore, the inter-domain identity authentication includes:
[0060] The first vehicle in the first domain calculates l=g H(ID) , choose a random number calculate C=H(l,w),u=r ID - C·l, forwarding the connection request π=(l, C, u) from the trusted authority in the first domain to the trusted authority in the second domain via a secure channel;
[0061] After receiving the connection request, the trusted authority in the second domain calculates w′=g u ·g C·l , w′=g u ·g C·l, calculate C′=H(l,w′) and verify whether the equation C′=C holds. If so, the identity verification succeeds;
[0062] If a first vehicle in a first domain wants to establish a communication connection with a second vehicle in a second domain, the first vehicle initiates a transaction tr={Acc i ,Acc j ,Re,coin i}, where Acc i For the payer, Acc j is the payee, Re is the transaction information, coin i The transaction amount; if the inter-domain blockchain verifies and reaches a consensus, the transaction is written into a new block and the transaction identifier is returned to the payer Acc i ; Payee Acc j After receiving the transfer, contact the payer Acc i Communication is performed as needed, otherwise, communication is terminated.
[0063] Furthermore, the identifying of illegal users includes:
[0064] The trusted authorization agency executes the Open algorithm Open(gmsk,m,σ)→(ID / ⊥), and uses the group owner's private key gmsk, the message m, and the signature σ as the input of the Open algorithm. If the output is ⊥, the user is an illegal user; if the user is a member of the group, the real identity information of the member is output.
[0065] Furthermore, the deregistration of illegal users includes:
[0066] The trusted authority generates the system parameters SP and the master key mk of the revocation tree;
[0067] According to the algorithm BuildTree(SP,mk,t,Acc), the node account information Acc of the tree is output. The master key mk is used to sign the child node of the tree, and the timestamp t is used to limit the validity period of the node.
[0068] According to the algorithm Addnode(Acc i ,t i ,sk i ) Output any node node i The child node Acc i And the key sk corresponding to the child node i , if and only if the child node contains the timestamp t i When the timestamp t of the parent node is newer, the child node is valid;
[0069] According to the algorithm Deletenode(Ac i c, i ′t,si k) Delete the child node Acc of a node i , generate a new timestamp t′ to update the node node i ,Since the time of the child node is older than the time of the parent node, the child node is invalid;
[0070] When the number of vehicles with expired identities meets the preset conditions, the Deletenode(Acc i ,t i ′,sk i ) algorithm updates the node t′ and cancels the account information Acc of the illegal user i .
[0071] Furthermore, the method further comprises:
[0072] Generate a blacklist: The trusted authority in each domain generates and maintains a blacklist based on the identified illegal users, and updates the user whose identity has expired in conjunction with the blacklist during identity renewal.
[0073] In the second aspect, the present invention provides a cross-domain authentication system under a vehicle-mounted ad hoc network, the cross-domain authentication system includes a key generation center, a trusted authorization agency in at least one domain corresponding to each area, and several roadside units and vehicles in each area, the vehicle is provided with an on-board unit for communicating with other vehicles and roadside units; the cross-domain authentication system is used to implement the above method.
[0074] The present invention provides a cross-domain authentication method and system for a vehicular ad hoc network. The method is implemented based on a cross-domain authentication system for the vehicular ad hoc network. The cross-domain authentication system includes a key generation center, at least one trusted authority within each domain corresponding to each area, and several roadside units and vehicles within each area. The method includes the following steps: system initialization, vehicle initialization, roadside unit initialization, threshold group signature construction, identity update, intra-domain identity authentication, inter-domain identity authentication, identification of illegal users, and deregistration of illegal users. The present invention provides a cross-domain authentication method that utilizes intra-domain private chains and inter-domain consortium chains to deploy a blockchain network, eliminating the problem of incomplete trust between domains during the cross-domain authentication process and ensuring trust barriers for cross-domain users. Furthermore, a non-interactive zero-knowledge proof is used to authenticate vehicle users without leaking user privacy. A tree-structured revocation mechanism is also used to revoke the identities of malicious users with destructive behavior and expired users within the domain, reducing system storage redundancy. Real-time monitoring is performed when a new user submits an authentication request or a vehicle undergoes cross-domain authentication to detect malicious users, thereby ensuring the long-term, secure and stable operation of the blockchain network. BRIEF DESCRIPTION OF THE DRAWINGS
[0075] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0076] Figure 1 A flowchart of a cross-domain authentication method in a vehicular ad hoc network according to an embodiment of the present invention;
[0077] Figure 2 A schematic flow chart of a cross-domain authentication method in a vehicular ad hoc network according to an embodiment of the present invention;
[0078] Figure 3 A schematic flow chart of a cross-domain authentication method in a vehicular ad hoc network according to another embodiment of the present invention;
[0079] Figure 4 A schematic diagram of a revocation tree structure in a cross-domain authentication method in a VANET according to an embodiment of the present invention. DETAILED DESCRIPTION
[0080] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.
[0081] An embodiment of the present invention provides a cross-domain authentication method for a vehicular ad hoc network. The method is implemented based on a cross-domain authentication system for the vehicular ad hoc network. The cross-domain authentication system includes a key generation center, at least one trusted authority within each domain, and several roadside units (ROUs) and vehicles within each domain. In this system, vehicle users have access to specific resources within the domain and, after authentication, can access resources within the specific domain on demand. Each vehicle is equipped with an onboard unit (OBU), which is responsible for simple communications and tasks. The RSU, as an intermediary entity with sufficient storage and computing capabilities, broadcasts traffic alerts, collects basic safety information from nearby vehicles, and communicates with the vehicle. RSUs act as intermediaries between vehicles and the larger communications infrastructure, facilitating data exchange, traffic management, and connectivity to the broader network, improving the overall communication efficiency and security of the vehicle network. Two types of blockchains are described in this application: intra-domain blockchains and inter-domain blockchains. Both are consortium chains. Intra-domain blockchains primarily maintain the identity registration information of vehicle users, while inter-domain blockchains are primarily for authorized nodes, resolving untrusted communications between domains and ensuring the validity and legitimacy of data within the chain by regularly updating vehicle user registration information.
[0082] like Figures 1 to 4 As shown, the cross-domain authentication method in a vehicular ad hoc network according to an embodiment of the present invention includes the following steps:
[0083] Step S10: System initialization: The trusted authority generates system parameters within the domain.
[0084] Specifically: Let F P Represent a finite field of order large prime number p, and a trusted authority constructs an elliptic curve E over the field;
[0085] Choose a generator P from E, a cyclic group G of order large prime number q;
[0086] Random selection of trusted authorities As the private key SK GA , the public key is obtained by calculation is a finite field;
[0087] Defining a secure hash function The common system parameters are {G,q,P,P pub ,H0,H1,H2},P pub The system public key.
[0088] Step S20: Vehicle initialization: The trusted authorization agency generates a pseudo-identity for the vehicle based on the system parameters within the domain and sends it to the vehicle through a secure channel. The vehicle verifies the pseudo-identity, obtains the corresponding public key and private key, and stores them.
[0089] Specifically: the vehicle generates a random number Calculate K i =k i P, then sends a registration request {Register||ID i ,K i ,t i}, where ID i It is a vehicle i The real identity information, t i Indicates the current timestamp of the registration request;
[0090] Trusted authority selects random number Calculating pseudonyms R i =r i P,h0=H0(PID i ,K i ,R i ),as well as s n is the system private key;
[0091] Generate identity certificate cert i =(Acc i ||ID i ||PID i ||gpk||t i ||T i ); Acc i is a blockchain account, gpk is a vehicle i The group public key of the domain, T i It is cert i validity period;
[0092] Generate pseudo-identity message {Response||cert i ||y i ||R i} and sent to the vehicle through a secure channel i ;
[0093] Vehicle i By calculating y i P=R i +H0(PID i ,K i ,R i )P pub , verify the pseudo identity; if the verification is successful, then (cert i ,K i ,k i ,R i ,y i) is stored on the blockchain within the domain, and the public key and private key of the vehicle are vpk i =K i , vsk i =k i .
[0094] Step S30: Roadside unit initialization: The trusted authority generates a key message for the roadside unit based on the system parameters in the domain and sends it to the corresponding roadside unit through a secure channel. The roadside unit verifies the key message, obtains the corresponding key and stores it.
[0095] Specifically: Roadside unit generates random numbers Calculate K j =k j P, and get the current time T j ∈{0,1} * , the message {Register||ID j ,K j ,T j} is sent to a trusted authority; where ID j The identity information of the roadside unit;
[0096] After receiving the message, the trusted authority generates a random number Calculate R j =r j P, h1=H1(ID j ,K j )as well as
[0097] Generate key message {Response||gpk,R j ,y j ,T j} and sent to the roadside unit via a secure channel;
[0098] Roadside units are calculated Verify the key message; if the verification is successful, {k j ,K j ,r j ,R j} is stored on the blockchain within the domain; the public key and private key of the roadside unit are vpk j =K j , vsk j =k j .
[0099] Step S40: Constructing a threshold group signature: Constructing a threshold group, which consists of several vehicles and roadside units as members; any vehicle in the threshold group generates a signature of the traffic message and broadcasts it, and the roadside unit or other vehicles receive the signed message and verify whether the signature is legal.
[0100] In this step, constructing a threshold group includes:
[0101] A threshold group signature scheme of (t,n) is used, where t is the threshold value and the threshold group is a set consisting of n members, represented by M={m1,m2,…,m t}(t≤n); The members of the threshold group include at least: group administrator GA, group member m i , signature verifier GV, θ is the traffic message that needs to be signed;
[0102] The group administrator GA randomly selects a secret value And calculate pk i =κ i P, where κ i =sk i ; Then secretly select a polynomial of degree t-1 where a iz ∈[1,p-1](z=0,1,…,t-1);
[0103] Calculate the group private key of the threshold group as sk gi =f i (0) = a i0 , calculate the public key of the threshold group as pk gi =f i (0)P=a i0 P;
[0104] Group member m i Randomly choose a secret value Calculate pk i =ν i P, and generate a temporary pseudonym ζ i ;
[0105] In this step, any vehicle in the threshold group generates a traffic message signature and broadcasts it, including:
[0106] Group member m i Through the private key sk i Sign traffic messages i =sk i I i +h i (θ)ν i modp, where h i (θ) is the hash value of the traffic message;
[0107] Group member m i Broadcasting the signature of the traffic message;
[0108] In this step, the roadside unit or other vehicle receives the signed message and verifies whether the signature is legitimate, including:
[0109] Single message authentication: via public user pseudonym PID i Computation I i And the hash value h of the traffic message i (θ), and by calculating ν i h i (θ)=s i P-pk i I i To verify whether the signature is legitimate;
[0110] And / or, batch message verification: When the group administrator GA receives N different signed messages, it calculates and verification message The threshold signature (S, V) and verification message Y are broadcast to the signature verifier GV in the group. When N ≥ t, SP is calculated to verify whether the signature is legal; where:
[0111]
[0112] Step S50: Identity update: Before performing intra-domain identity authentication, the trusted authority updates the user's expired identity by calling an update algorithm.
[0113] Specifically include: Vehicle inspection identity certificate cert i Whether it is expired. If so, submit an update request {IDUpData} to the trusted authority through the roadside unit;
[0114] The trusted authority calls the update algorithm to complete the vehicle identity update;
[0115] The roadside unit submits the user's blockchain account Acc to the trusted authority i , group public key gpk and T i Perform identity updates;
[0116] The trusted authority verifies the validity of the signature through gpk. If it is valid, Time = T i new ;
[0117] Output T i new , gpk updates user identity information.
[0118] Step S60: Intra-domain identity authentication: The trusted authorization agency in the domain authenticates the vehicle identity. After the identity authentication is successful, the vehicle establishes a communication connection with other vehicles in the domain.
[0119] Specifically including: the vehicle will identify the certificate i Send to the current roadside unit via a secure channel;
[0120] After receiving the roadside unit, it first verifies T i If valid, the consistency of the group public key gpk is verified. If they are the same, the authentication is successful.
[0121] Establishing a communication connection between the first vehicle and another second vehicle in the domain, the process includes:
[0122] The first vehicle uses the private key vsk i Sign the request message And send a request to establish communication to the second vehicle through the secure channel {request||σ i};
[0123] After the second vehicle receives it, j Extract the group public key gpk and verify the signature. If the verification is successful, it proves that the two belong to the same domain.
[0124] The second vehicle uses the private key vsk j Sign the response message And send a response to the communication request {response||σ j};
[0125] After the first vehicle receives the identity certificate i Extract the group public key gpk pair σ j Verification is performed, and if the verification is successful, a communication connection is established between the first vehicle and the second vehicle.
[0126] Step S70: Inter-domain identity authentication: The vehicle in the first domain initiates an inter-domain connection request, which is forwarded by a trusted authorization agency in the first domain and authenticated by a trusted authorization agency in the second domain. If the authentication is successful, the vehicle in the first domain establishes a communication connection with the vehicle in the second domain.
[0127] This step specifically includes: calculating l=g for the first vehicle in the first domain. H(ID) , choose a random number calculate C=H(l,w),u=r ID- C·l, forwarding the connection request π=(l, C, u) from the trusted authority in the first domain to the trusted authority in the second domain via a secure channel;
[0128] After receiving the connection request, the trusted authority in the second domain calculates w′=g u ·g C·l , w′=g u ·g C·l , calculate C′=H(l,w′) and verify whether the equation C′=C holds. If so, the identity verification succeeds;
[0129] If a first vehicle in a first domain wants to establish a communication connection with a second vehicle in a second domain, the first vehicle initiates a transaction tr={Acc i ,Acc j ,Re,coin i}, where Acc i For the payer, Acc j is the payee, Re is the transaction information, coin i The transaction amount; if the inter-domain blockchain verifies and reaches a consensus, the transaction is written into a new block and the transaction identifier is returned to the payer Acc i ; Payee Acc j After receiving the transfer, contact the payer Acc i Communication is performed as needed, otherwise, communication is terminated.
[0130] Step S80: Identify illegal users: The trusted authorization agency authenticates the users in the domain and identifies illegal users.
[0131] This step specifically includes: the trusted authorization agency executes the Open algorithm Open(gmsk,m,σ)→(ID / ⊥), using the group owner's private key gmsk, the message m, and the signature σ as inputs to the Open algorithm. If the output is ⊥, the user is an illegal user; if the user is a member of the group, the member's real identity information is output.
[0132] Step S90: Cancel illegal users: The trusted authorization agency establishes a revocation tree on the blockchain. When there is an illegal user, the trusted authorization agency cancels the registration information of the illegal user.
[0133] This step specifically includes: the trusted authority generates the system parameters SP and the master key mk of the revocation tree;
[0134] According to the algorithm BuildTree(SP,mk,t,Acc), the node account information Acc of the tree is output. The master key mk is used to sign the child node of the tree, and the timestamp t is used to limit the validity period of the node.
[0135] According to the algorithm Addnode(Acc i ,t i ,sk i ) Output any node node i The child node Acc i And the key sk corresponding to the child node i , if and only if the child node contains the timestamp t i When the timestamp t of the parent node is newer, the child node is valid;
[0136] According to the algorithm Deletenode(Acc i ,t i ′,sk i ) Delete the child node Acc of a node i , generate a new timestamp t′ to update the node node i ,Since the time of the child node is older than the time of the parent node, the child node is invalid;
[0137] When the number of vehicles with expired identities meets the preset conditions, the Deletenode(Acc i ,t i ′,sk i ) algorithm updates the node t′ and cancels the account information Acc of the illegal user i .
[0138] Another embodiment of the present invention further includes:
[0139] Step S100: Generate a blacklist: The trusted authority in each domain generates and maintains a blacklist based on the identified illegal users, and updates the user whose identity has expired in conjunction with the blacklist when the identity is updated.
[0140] In this embodiment, each domain needs to jointly maintain a blacklist, which is compiled by the trusted authorization agency of each domain and collected and reported by the roadside units. The information of malicious users tracked by the system will be uploaded to the list. Before new users are updated, the list will be queried to ensure system security.
[0141] A cross-domain authentication system under a vehicle-mounted ad hoc network in an embodiment of the present invention includes a key generation center, a trusted authorization agency in at least one domain corresponding to each area, and several roadside units and vehicles in each area. The vehicle is provided with an on-board unit for communicating with other vehicles and roadside units; the cross-domain authentication system is used to implement the above-mentioned method embodiment, and the specific process will not be repeated here.
[0142] The present invention provides a cross-domain authentication method and system for a vehicular ad hoc network. The method is implemented based on a cross-domain authentication system for the vehicular ad hoc network. The cross-domain authentication system includes a key generation center, at least one trusted authority within each domain corresponding to each area, and several roadside units and vehicles within each area. The method includes the following steps: system initialization, vehicle initialization, roadside unit initialization, threshold group signature construction, identity update, intra-domain identity authentication, inter-domain identity authentication, identification of illegal users, and deregistration of illegal users. The present invention provides a cross-domain authentication method that utilizes intra-domain private chains and inter-domain consortium chains to deploy a blockchain network, eliminating the problem of incomplete trust between domains during the cross-domain authentication process and ensuring trust barriers for cross-domain users. Furthermore, a non-interactive zero-knowledge proof is used to authenticate vehicle users without leaking user privacy. A tree-structured revocation mechanism is also used to revoke the identities of malicious users with destructive behavior and expired users within the domain, reducing system storage redundancy. Real-time monitoring is performed when a new user submits an authentication request or a vehicle undergoes cross-domain authentication to detect malicious users, thereby ensuring the long-term, secure and stable operation of the blockchain network.
[0143] The present invention is further described above with the aid of specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the essence and scope of the present invention. Various modifications made to the above embodiments by ordinary technicians in this field after reading this specification are all within the scope of protection of the present invention.
Claims
1. A cross-domain authentication method in a vehicle-mounted ad hoc network, characterized in that: The method is implemented based on a cross-domain authentication system in a vehicle-mounted ad hoc network. The cross-domain authentication system includes a key generation center, a trusted authority in at least one domain corresponding to each area, and several roadside units and vehicles in each area. The method comprises the following steps: System initialization: the trusted authority generates system parameters within the domain; Vehicle initialization: The trusted authority generates a pseudo-identity for the vehicle based on the system parameters within the domain and sends it to the vehicle via a secure channel. The vehicle verifies the pseudo-identity, obtains the corresponding public key and private key, and stores them. Roadside unit initialization: the trusted authority generates a key message for the roadside unit based on the system parameters in the domain and sends it to the corresponding roadside unit through a secure channel. The roadside unit verifies the key message, obtains the corresponding key, and stores it; Constructing a threshold group signature: Constructing a threshold group, which is composed of several vehicles and roadside units as members; any vehicle in the threshold group generates a signature for a traffic message and broadcasts it, and the roadside unit or other vehicles receive the signed message and verify whether the signature is legitimate; Identity update: Before performing intra-domain identity authentication, the trusted authority updates the user's identity by calling the update algorithm; Intra-domain identity authentication: A trusted authority within the domain authenticates the vehicle's identity. After successful authentication, the vehicle establishes a communication connection with other vehicles within the domain. Inter-domain identity authentication: A vehicle in the first domain initiates an inter-domain connection request, which is forwarded by a trusted authority in the first domain. The trusted authority in the second domain performs identity authentication. If the authentication succeeds, the vehicle in the first domain establishes a communication connection with the vehicle in the second domain. Identify illegal users: The trusted authorization agency authenticates users within the domain and identifies illegal users; Cancelling illegal users: The trusted authorization agency establishes a revocation tree on the blockchain. When there is an illegal user, the trusted authorization agency cancels the registration information of the illegal user.
2. A cross-domain authentication method in a vehicle-mounted ad hoc network according to claim 1, characterized in that: System initialization includes: Let F P represents a finite field of order p, over which the trusted authority constructs an elliptic curve E; Choose a generator P from E, a cyclic group G of order large prime number q; The trusted authority randomly selects As the private key SK GA , the public key is obtained by calculation is a finite field; Defining a secure hash function The common system parameters are {G,q,P,P pub ,H0,H1,H2},P pub is the system public key; The vehicle initialization includes: The vehicle generates a random number Calculate K i =k i P, then sends a registration request {Register||ID i ,K i ,t i }, where ID i It is a vehicle i The real identity information, t i Indicates the current timestamp of the registration request; The trusted authority selects a random number Calculating pseudonyms R i =r i P,h0=H0(PID i ,K i ,R i ),as well as s n is the system private key; Generate identity certificate cert i =(Acc i ||ID i ||PID i ||gpk||t i ||T i ); Acc i is a blockchain account, gpk is a vehicle i The group public key of the domain, T i It is cert i validity period; Generate pseudo-identity message {Response||cert i ||y i ||R i } and sent to the vehicle through a secure channel i ; The vehicle i By calculating y i P=R i +H0(PID i ,K i ,R i )P pub , verify the pseudo identity; if the verification is successful, then (cert i ,K i ,k i ,R i ,y i ) is stored on the blockchain within the domain, and the public key and private key of the vehicle are vpk i =K i , vsk i =k i ; The roadside unit initialization includes: The roadside unit generates a random number Calculate K j =k j P, and get the current time T j ∈{0,1} * , the message {Register||ID j ,K j ,T j } is sent to the trusted authority; wherein, ID j is the identity information of the roadside unit; After receiving the message, the trusted authority generates a random number Calculate R j =r j P, h1=H1(ID j ,K j )as well as Generate key message {Response||gpk,R j ,y j ,T j }, and sent to the roadside unit via a secure channel; The roadside unit is calculated by Verify the key message; if the verification is successful, {k j ,K j ,r j ,R j } is stored on the blockchain within the domain; the public key and private key of the roadside unit are vpk j =K j , vsk j =k j .
3. A cross-domain authentication method in a vehicle-mounted ad hoc network according to claim 2, characterized in that: The construction threshold group includes: A threshold group signature scheme of (t,n) is used, where t is the threshold value and the threshold group is a set consisting of n members, represented by M={m1,m2,…,m t }(t≤n); The members of the threshold group include at least: group administrator GA, group member m i , signature verifier GV, θ is the traffic message that needs to be signed; The group administrator GA randomly selects a secret value And calculate pk i =κ i P, where κ i =sk i ; Then secretly select a polynomial of degree t-1 Among them, a iz ∈[1,p-1](z=0,1,…,t-1); Calculate the group private key of the threshold group as sk gi =f i (0) = a i0 , calculate the public key of the threshold group as pk gi =f i (0)P=a i0 P; Group member m i Randomly choose a secret value Calculate pk i =ν i P, and generate a temporary pseudonym ζ i ; Any of the vehicles in the threshold group generates a signature of a traffic message and broadcasts the signature, including: Group member m i Through the private key sk i Sign traffic messages i =sk i I i +h i ( )ν i mod p, where h i ( ) is the hash value of the traffic message; Group member m i Broadcasting the signature of the traffic message; The roadside unit or other vehicle receives the signed message and verifies whether the signature is legitimate, including: Single message authentication: via public user pseudonym PID i Computation I i And the hash value h of the traffic message i (θ), and by calculating ν i h i (θ)=s i P-pk i I i To verify whether the signature is legitimate; And / or, batch message verification: When the group administrator GA receives N different signed messages, it calculates and verification message The threshold signature (S, V) and verification message Y are broadcast to the signature verifier GV in the group. When N ≥ t, SP is calculated to verify whether the signature is legal; where:
4. A cross-domain authentication method in a vehicle-mounted ad hoc network according to claim 3, characterized in that: Identity updates include: Vehicle inspection identity certificate cert i Whether it is expired, if so, submitting an update request {IDUpData} to the trusted authority through the roadside unit; The trusted authority calls the update algorithm to complete the identity update of the vehicle; The roadside unit submits the user's blockchain account Acc to the trusted authority i , group public key gpk and T i Perform identity updates; The trusted authority verifies the validity of the signature through gpk. If it is valid, Time = T i new ; Output T i new , gpk updates user identity information.
5. A cross-domain authentication method in a vehicle-mounted ad hoc network according to claim 4, characterized in that: The intra-domain identity authentication includes: The vehicle will send its identity certificate i Send to the current roadside unit via a secure channel; After receiving the T i If valid, the consistency of the group public key gpk is verified. If they are the same, the authentication is successful. Establishing a communication connection between the first vehicle and another second vehicle in the domain, the process includes: The first vehicle uses the private key vsk i Sign the request message And send a request to establish communication to the second vehicle through a secure channel {request||σ i }; After the second vehicle receives it, j Extract the group public key gpk and verify the signature. If the verification is successful, it proves that the two belong to the same domain. The second vehicle uses the private key vsk j Sign the response message And send a response to the communication request {response||σ j }; After the first vehicle receives the identity certificate i Extract the group public key gpk pair σ j Verification is performed, and if the verification is successful, a communication connection is established between the first vehicle and the second vehicle.
6. A cross-domain authentication method in a vehicular ad hoc network according to claim 5, characterized in that: The inter-domain identity authentication includes: The first vehicle in the first domain calculates l=g H(ID) , choose a random number Calculate w = g rID ,C=H(l,w),u=r ID - C·l, forwarding the connection request π=(l, C, u) from the trusted authority in the first domain to the trusted authority in the second domain via a secure channel; After receiving the connection request, the trusted authority in the second domain calculates w′=g u ·g C·l , w′=g u ·g C·l , calculate C′=H(l,w′) and verify whether the equation C′=C holds. If so, the identity verification succeeds; If a first vehicle in a first domain wants to establish a communication connection with a second vehicle in a second domain, the first vehicle initiates a transaction tr={Acc i ,Acc j ,Re,coin i }, where Acc i For the payer, Acc j is the payee, Re is the transaction information, coin i The transaction amount; if the inter-domain blockchain verifies and reaches a consensus, the transaction is written into a new block and the transaction identifier is returned to the payer Acc i ; Payee Acc j After receiving the transfer, contact the payer Acc i Communication is performed as needed, otherwise, communication is terminated.
7. A cross-domain authentication method in a vehicle-mounted ad hoc network according to claim 6, characterized in that: The identification of illegal users includes: The trusted authorization agency executes the Open algorithm Open(gmsk,m,σ)→(ID / ⊥), and uses the group owner's private key gmsk, the message m, and the signature σ as the input of the Open algorithm. If the output is ⊥, the user is an illegal user; if the user is a member of the group, the real identity information of the member is output.
8. The cross-domain authentication method in a vehicle-mounted ad hoc network according to claim 7, characterized in that: The cancellation of illegal users includes: The trusted authority generates the system parameters SP and the master key mk of the revocation tree; According to the algorithm BuildTree(SP,mk,t,Acc), the node account information Acc of the tree is output. The master key mk is used to sign the child node of the tree, and the timestamp t is used to limit the validity period of the node. According to the algorithm Addnode(Acc i ,t i ,sk i ) Output any node node i The child node Acc i And the key sk corresponding to the child node i , if and only if the child node contains the timestamp t i When the timestamp t of the parent node is newer, the child node is valid; According to the algorithm Deletenode(Acc i ,t i ′,sk i ) Delete the child node Acc of a node i , generate a new timestamp t′ to update the node node i ,Since the time of the child node is older than the time of the parent node, the child node is invalid; When the number of vehicles with expired identities meets the preset conditions, the Deletenode(Acc i ,t i ′,sk i ) algorithm updates the node t′ and cancels the account information Acc of the illegal user i .
9. A cross-domain authentication method in a vehicle-mounted ad hoc network according to claim 8, characterized in that: The method also includes: Generate a blacklist: The trusted authority in each domain generates and maintains a blacklist based on the identified illegal users, and updates the user whose identity has expired in conjunction with the blacklist during identity renewal.
10. A cross-domain authentication system in a vehicle-mounted ad hoc network, characterized in that: The cross-domain authentication system includes a key generation center, a trusted authorization agency in at least one domain corresponding to each area, and several roadside units and vehicles in each area. The vehicle is provided with an on-board unit for communicating with other vehicles and roadside units; the cross-domain authentication system is used to implement the method described in any one of claims 1 to 9.