SM2 signcryption method and system supporting quick revocation in vehicle-mounted network environment

Abstract

The invention provides an SM2 signcryption method and system supporting rapid revocation in a vehicle-mounted network environment. The method comprises the steps of generating a global public parameter set and a master key of the system, initializing roadside infrastructures, initializing an authentication server, generating a vehicle anonymous identity and an implicit certificate, generating a vehicle and a corresponding private key, generating a signcryption ciphertext, decrypting and verifying, and tracking and cancelling. The invention further provides an SM2 signcryption system supporting rapid revocation in the vehicle-mounted network environment, and the SM2 signcryption system comprises a system initialization module, a legal vehicle registration module, a vehicle pseudonym generation module, a message signcryption generation module, a message decryption verification module and a tracking revocation module. And the storage capacity of the block chain is not additionally increased. When the vehicle breaks the law, the trusted center can realize quick revocation through a method of logically deleting the certificate of the vehicle.

Description

Technical Field

[0001] The present invention proposes an SM2 signcryption method and system supporting rapid revocation in a vehicle-mounted network environment, relating to the technical field of data signcryption in information security. Background Art

[0002] Communication between entities in the in-vehicle network primarily relies on dedicated short-range communication technologies, conducted over public wireless channels. However, plaintext data can be stolen, tampered with, or forged during transmission by attackers, leading to traffic accidents and threatening driver safety. Furthermore, attackers can eavesdrop on public channels and obtain vehicle identification information, resulting in information leaks. Therefore, while ensuring data confidentiality and authentication, protecting the identity privacy of vehicles is equally important. Anonymity mechanisms are an effective solution to address identity privacy leaks, but absolute anonymity makes it impossible to hold violators accountable.

[0003] Signcryption enables the signing and encryption of messages in a single logical step. Since its introduction, it has rapidly attracted significant attention in the cryptography community, and numerous signcryption schemes have been proposed. In 2014, Han et al. proposed a vehicle authentication protocol based on signcryption technology, which simultaneously ensures data confidentiality and authentication. However, it suffers from drawbacks such as complex certificate management, opaque certificate issuance and revocation, and high certificate / key revocation overhead. Subsequently, in 2015, He et al. attempted to optimize certificate management and improve authentication efficiency using identity-based cryptography. However, the complete private key is escrowed by a third party, making it difficult for users to revoke it. In 2021, Ali et al. introduced a certificateless cryptography system, addressing the key escrow issue by having the vehicle and a key generation center collaborate to generate the private key. However, the revocation problem remains a significant issue. While pseudonymous revocation lists can be used to ensure revocation flexibility, the increasing number of revoked vehicles will lead to significant storage overhead and retrieval delays. Furthermore, maintaining synchronous updates to the revocation list presents a real challenge. Blockchain, a decentralized distributed ledger technology with the characteristics of immutability, traceability, and autonomy, provides technical support for optimized certificate management and rapid revocation in vehicle networks. Feng et al. proposed a blockchain-assisted anonymous authentication protocol that manages the pseudonym and public key of vehicles through smart contracts, but did not achieve message unlinkability.

[0004] At the same time, existing secure communication mechanisms for in-vehicle networks primarily rely on foreign cryptographic algorithms, while proprietary Chinese cryptographic algorithms are rarely used. An et al. proposed an aggregate signature scheme for in-vehicle networks, combining the Chinese SM9 cryptographic algorithm. This scheme effectively reduces verification overhead, but key escrow and revocation issues remain. House et al. constructed a multi-signature protocol and applied it to in-vehicle vehicle-to-infrastructure collaborative communications, reducing infrastructure verification overhead. However, these schemes often offer limited functionality or inefficiency, making them difficult to directly apply to complex, real-world in-vehicle network scenarios. Summary of the Invention

[0005] Purpose of the Invention: To provide more comprehensive in-vehicle network security and avoid potential backdoor threats from foreign algorithms, this paper proposes an SM2 signcryption method and system that supports rapid revocation in an in-vehicle network environment, based on the national SM2 algorithm and supplemented by blockchain technology. This method provides rapid vehicle revocation while also protecting message authentication and confidentiality.

[0006] The present invention adopts the following technical solution to solve the above technical problems: an SM2 signcryption method and system supporting rapid revocation in a vehicle network environment, comprising the following contents:

[0007] An SM2 signcryption method supporting rapid revocation in an in-vehicle network environment is characterized by using an SM2 signcryption system supporting rapid revocation, wherein the SM2 signcryption system includes a trusted center, roadside infrastructure, an authentication server, a vehicle, and a blockchain, and wherein the SM2 signcryption method supporting rapid revocation in an in-vehicle network environment comprises the following steps:

[0008] Step A: Based on the security parameters and the trusted center, the system's global public parameter set and master key are generated and initialized for the roadside infrastructure and authentication server;

[0009] Step B: Based on the system's global public parameter set, the vehicle's identity, and the trusted center, an anonymous identity and implicit certificate are generated for the legitimate vehicle and uploaded to the smart contract in the blockchain;

[0010] Step C: Generate a pseudonym and corresponding private key for the vehicle based on the system's global public parameter set, the vehicle's identity and anonymous identity;

[0011] Step D: Based on the system's global public parameter set, the vehicle's private key and pseudonym, and the roadside infrastructure's public key, the vehicle signencrypts the message and sends the signcrypted result to the roadside infrastructure.

[0012] Step E: Based on the system's global public parameter set, the vehicle's signcryption information, and the roadside infrastructure's private key, the roadside infrastructure decrypts and verifies the message signcryption result from the vehicle.

[0013] Step F: Based on the system's global public parameter set, the verification results of the roadside infrastructure, and the vehicle's pseudonym, the trusted center tracks the identity corresponding to the illegal vehicle pseudonym and revokes the vehicle.

[0014] Furthermore, step A includes the following:

[0015] Step A1: The trusted center uses the security parameter λ∈Z q * , generate a prime number q of λ bits, a q-order elliptic curve group G, where Z q * is a set of positive integers;

[0016] Step A2: The trusted center selects a generator P from the elliptic curve group G and randomly selects an integer d TA ∈Z q * As the system master private key, calculate the system master public key Q TA =d TA P;

[0017] Step A3: The trusted center defines three hash functions H2:G×G→{0,1} λ , Where H1 is {0,1} * and elements in group G to set The hash function H2 is the sum of G and G to the set The hash function H3 is {0,1} * and To the collection The hash function of {0,1} * It is a set of binary symbol strings of variable length;

[0018] Step A4: The trusted center compiles the smart contract and deploys it to the blockchain and returns the address scid of the smart contract.

[0019] Furthermore, step B includes the following:

[0020] Step B1: Vehicle selection random number γ∈Z q * , calculate A=γPA=γP, and then transmit A and identity RID through the secure channel V ∈{0,1} * The identity is transmitted to the trusted center, which verifies the legitimacy of the identity. If it is not legal, the identity is rejected. Otherwise, step B2 is executed.

[0021] Step B2: The trusted center randomly selects β∈Z q* ,calculate and Where AID is the anonymous identity of the vehicle;

[0022] Step B3: Trusted Center Computation and Implicit Certificate and Return the certificate to the vehicle Upload to the smart contract in the blockchain;

[0023] Step B4: Vehicle Calculation and Verify Q V =d V P, when the equality holds, the certificate is valid.

[0024] Furthermore, step C includes the following:

[0025] Step C1: Vehicle randomly selects z∈Z q * , calculate Z = zP, pseudonym PID1 = zQ AS and PID2 = AID ⊕ H1 (PID1, Z);

[0026] Step C2: The vehicle calculates the pseudonymous private key d PID =(z·f+d V )modq, where f = H2(PID2,Z);

[0027] Step C3: The vehicle sends the pseudonym PID = (PID1, PID2) and the private key d PID Store for backup.

[0028] Furthermore, step D includes the following:

[0029] Step D1: Vehicle randomly selects k∈Z q * , calculate K=kP=(x K ,y K ), e=H1(m,K) and r=(x K +e)modq, where the message m∈{0,1} λ If r+k=q or r=0, reselect k, otherwise execute step D2;

[0030] Step D2: Vehicle calculation s=(1+d PID ) -1 (kd PID r) modq, if s≠0, then calculate U = kQ RSU and C=m⊕H2(U,K), otherwise terminate the program;

[0031] Step D3: The vehicle signs the ciphertext as CT = (C, U, s), and sends CT, the anonymous identity PID, and the current timestamp ts to the infrastructure RSU through the wireless channel.

[0032] Furthermore, step E includes the following:

[0033] Step E1: The RSU receives (CT, PID, ts) and checks whether the timestamp ts is fresh. If so, it sends a query request to the authentication server AS in the local area through a secure wired channel. Otherwise, it discards the message.

[0034] Step E2: After receiving the query request, AS calculates Z'=d AS PID1 and AID = PID2 ⊕ H1 (PID1, Z'), retrieve the corresponding certificate from the blockchain

[0035] Step E3: AS calculation And search the local database for the public key of the corresponding certificate If it exists, return it directly, otherwise calculate And (h',Q V ) is stored in the local database;

[0036] Step E4: AS calculates f=H2(PID2,Z') and vehicle pseudonym public key Q PID =fZ'+Q V , and Q PID Return to RSU;

[0037] Step E5: RSU calculates K'=d R -1 U, recover the plaintext message m'=C⊕H2(U,K');

[0038] Step E6: RSU calculates e'=H1(m',K') and t'=(e'+x K' +s)modq, if t'≠0 and K'=sP+tQ PID , then output the decrypted message m, otherwise output the error symbol ⊥.

[0039] Furthermore, step F includes the following:

[0040] Step F1: The trusted center looks up the private key d of the current region AS AS , calculate Z'=d AS PID1, thereby obtaining the anonymous identity of the tracked vehicle AID=PID2⊕H1(PID1,Z');

[0041] Step F2: The trusted center searches for the corresponding certificate Recovering the true identity of tracked vehicles And the identity RID V Mark as illegal;

[0042] Step F3: The trusted center revokes the certificate from the smart contract

[0043] The present invention provides an SM2 signcryption system supporting rapid revocation in an in-vehicle network environment, which is used to implement an SM2 signcryption method supporting rapid revocation in an in-vehicle network environment as described in any one of the present inventions. The SM2 signcryption system supporting rapid revocation in an in-vehicle network environment includes a system initialization module, a legal vehicle registration module, a vehicle pseudonym generation module, a message signcryption generation module, a message decryption verification module, and a tracking and revocation module.

[0044] The system initialization module is used to generate the system's global public parameter set and master key based on the input security parameters. Furthermore, the system initialization module initializes the roadside infrastructure and authentication server;

[0045] The legal vehicle registration module is used to identify the vehicle based on the system's global public parameter set. Furthermore, the trusted center is responsible for generating anonymous identities and implicit certificates for legal vehicles and uploading them to the smart contract in the blockchain.

[0046] The vehicle pseudonym generation module is used to generate its own pseudonym and corresponding private key based on the system's global public parameter set, the vehicle's identity and anonymous identity;

[0047] The message signcryption generation module is used to signcrypt the message based on the system's global public parameter set, the vehicle's private key and pseudonym, and the roadside infrastructure's public key, and send the signcryption result to the roadside infrastructure.

[0048] The message decryption and verification module is used to decrypt and verify the message signcryption result from the vehicle based on the system's global public parameter set, the vehicle's signcryption, and the roadside infrastructure's private key.

[0049] The tracking and revocation module is used to track the identity corresponding to the illegal vehicle pseudonym and revoke the vehicle based on the system's global public parameter set, the verification results of the roadside infrastructure, and the vehicle's pseudonym.

[0050] According to a second aspect of the present invention, an SM2 signcryption system that supports rapid revocation in an in-vehicle network environment includes an electronic device, wherein the electronic device includes a memory, a processor, and a computer program stored in the memory and runnable on the processor, and is characterized in that when the processor executes the computer program, it implements an SM2 signcryption method that supports rapid revocation in an in-vehicle network environment as described in any one of the present inventions.

[0051] According to a third aspect of the present invention, an SM2 signcryption system that supports rapid revocation in an in-vehicle network environment includes a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and is characterized in that when the computer program is executed by a processor, it implements an SM2 signcryption method that supports rapid revocation in an in-vehicle network environment as described in any one of the present inventions.

[0052] The present invention has the following advantages:

[0053] 1) This paper proposes an efficient signcryption method based on SM2, which realizes the authentication and confidentiality of data in one logical step, and demonstrates its security under the random oracle machine model.

[0054] 2) Based on the proposed signcryption scheme and integrating blockchain smart contract technology, this paper designs an SM2 signcryption method and system that supports rapid revocation in a vehicle-to-vehicle network environment. Vehicles can self-generate pseudonyms for communication without increasing the blockchain's storage capacity. If a vehicle violates the law, the trusted center can quickly revoke its certificate by logically deleting it.

[0055] 3) The protocol verification process of the present invention can be processed in batches and does not involve time-consuming bilinear pairing operations. At the same time, the ECQV implicit certificate technology is used to reduce the storage burden of the certificate. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 This is a flowchart of an SM2 signcryption method supporting rapid revocation in a vehicle network environment described in the present invention.

[0057] Figure 2 This is a system model diagram of an SM2 signcryption method supporting rapid revocation in a vehicle network environment described in the present invention.

[0058] Figure 3 3 is a comparison chart of the calculation time consumption in each stage of the embodiment of the present invention. DETAILED DESCRIPTION

[0059] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.

[0060] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0061] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form, and it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0062] The present invention proposes an SM2 signcryption method and system supporting rapid revocation in an in-vehicle network environment. The SM2 signcryption method supporting rapid revocation in an in-vehicle network environment can be implemented using an elliptic curve group over a prime number field. The basic knowledge of prime number fields and elliptic curve groups includes the following:

[0063] Let p be a prime number, then the set F = {0, 1, ..., p-1} forms a p-order finite field with respect to addition and multiplication operations, also called the prime field, denoted by F p Let a,b∈F p And satisfy 4a 3 +27b 2 (mod p)≠0, then the prime field F p On the elliptic curve (denoted as E(F p ))'s equation satisfies y 2 =x 3 +ax+b. Point (x,y)∈F on the elliptic curve p ×F p and the infinite point O form an additive cyclic group, which is called the elliptic curve group, denoted by G, that is, G={(x,Y)∈F p ×F p |y 2 =x 3 +ax+b∧4a 3 +27b 2 (mod p)≠0∧a,b∈F p}∪{O}.

[0064] The concept of additive cyclic group is: let G be a group. If there exists an element P∈G such that G={nP|n∈Z}, then G is called additive cyclic group, and P is called the generator of group G. If the order of generator P is q (i.e., q is the smallest positive integer such that the multiple of P is equal to the identity element of group G), then G is called q-order cyclic group. In addition, where Z qrefers to the remainder class of integers modulo q, namely Z q ={0,1,…,q-1}.

[0065] like Figure 1 、 Figure 2 As shown, the present invention proposes an SM2 signcryption method and system that supports rapid revocation in an in-vehicle network environment, characterized in that an SM2 signcryption system that supports rapid revocation is used, wherein the SM2 signcryption system includes a trusted center, roadside infrastructure, an authentication server, a vehicle, and a blockchain. The trusted center issues a valid certificate to the vehicle and records the certificate in the blockchain; the authentication server is deployed by the trusted center and uses the roadside infrastructure to authenticate the legitimacy of the message source; when a malicious vehicle is discovered, the trusted center can also reveal its true identity and revoke its certificate. Furthermore, the SM2 signcryption method that supports rapid revocation in an in-vehicle network environment includes the following steps:

[0066] Step A: Based on the security parameters and the trusted center, the system's global public parameter set and master key are generated and initialized for the roadside infrastructure and authentication server;

[0067] Step B: Based on the system's global public parameter set, the vehicle's identity, and the trusted center, an anonymous identity and implicit certificate are generated for the legitimate vehicle and uploaded to the smart contract in the blockchain;

[0068] Step C: Generate a pseudonym and corresponding private key for the vehicle based on the system's global public parameter set, the vehicle's identity and anonymous identity;

[0069] Step D: Based on the system's global public parameter set, the vehicle's private key and pseudonym, and the roadside infrastructure's public key, the vehicle signencrypts the message and sends the signcrypted result to the roadside infrastructure.

[0070] Step E: Based on the system's global public parameter set, the vehicle's signcryption information, and the roadside infrastructure's private key, the roadside infrastructure decrypts and verifies the message signcryption result from the vehicle.

[0071] Step F: Based on the system's global public parameter set, the verification results of the roadside infrastructure, and the vehicle's pseudonym, the trusted center tracks the identity corresponding to the illegal vehicle pseudonym and revokes the vehicle.

[0072] In one embodiment of the present invention, step A includes the following:

[0073] Step A1: The trusted center uses the security parameter λ∈Z q * , generate a prime number q of λ bits, a q-order elliptic curve group G, where Z q * is a set of positive integers;

[0074] Step A2: The trusted center selects a generator P from the elliptic curve group G and randomly selects an integer d TA ∈Z q * As the system master private key, calculate the system master public key Q TA =d TA P;

[0075] Step A3: The trusted center defines three hash functions H2:G×G→{0,1} λ , Where H1 is {0,1} * and elements in group G to set The hash function H2 is the sum of G and G to the set The hash function H3 is {0,1} * and To the collection The hash function of {0,1} * It is a set of binary symbol strings of variable length;

[0076] Step A4: The trusted center compiles the smart contract and deploys it to the blockchain and returns the address scid of the smart contract.

[0077] In one embodiment of the present invention, step B includes the following:

[0078] Step B1: Vehicle selection random number γ∈Z q * , calculate A=γPA=γP, and then transmit A and identity RID through the secure channel V ∈{0,1} * The identity is transmitted to the trusted center, which verifies the legitimacy of the identity. If it is not legal, the identity is rejected. Otherwise, step B2 is executed.

[0079] Step B2: The trusted center randomly selects β∈Z q * ,calculate and Where AID is the anonymous identity of the vehicle;

[0080] Step B3: Trusted Center Computation and Implicit Certificate and Return the certificate to the vehicle Upload to the smart contract in the blockchain;

[0081] Step B4: Vehicle Calculation and Verify Q V =d V P, when the equality holds, the certificate is valid.

[0082] In one embodiment of the present invention, step C includes the following:

[0083] Step C1: Vehicle randomly selects z∈Z q * , calculate Z = zP, pseudonym PID1 = zQ AS and PID2 = AID ⊕ H1 (PID1, Z);

[0084] Step C2: The vehicle calculates the pseudonymous private key d PID =(z·f+d V ) mod q, where f = H2(PID2, Z);

[0085] Step C3: The vehicle sends the pseudonym PID = (PID1, PID2) and the private key d PID Store for backup.

[0086] In one embodiment of the present invention, step D includes the following:

[0087] Step D1: Vehicle randomly selects k∈Z q * , calculate K=kP=(x K ,y K ), e=H1(m,K) and r=(x K +e)modq, where the message m∈{0,1} λ If r+k=q or r=0, reselect k, otherwise execute step D2;

[0088] Step D2: Vehicle calculation s=(1+d PID ) -1 (kd PID r) modq, if s≠0, then calculate U = kQ RSU and C=m⊕H2(U,K), otherwise terminate the program;

[0089] Step D3: The vehicle signs the ciphertext as CT = (C, U, s), and sends CT, the anonymous identity PID, and the current timestamp ts to the infrastructure RSU through the wireless channel.

[0090] In one embodiment of the present invention, step E includes the following:

[0091] Step E1: The RSU receives (CT, PID, ts) and checks whether the timestamp ts is fresh. If so, it sends a query request to the authentication server AS in the local area through a secure wired channel. Otherwise, it discards the message.

[0092] Step E2: After receiving the query request, AS calculates Z'=d AS PID1 and AID = PID2 ⊕ H1 (PID1, Z'), retrieve the corresponding certificate from the blockchain

[0093] Step E3: AS calculation And search the local database for the public key of the corresponding certificate If it exists, return it directly, otherwise calculate And (h',Q V ) is stored in the local database;

[0094] Step E4: AS calculates f=H2(PID2,Z') and vehicle pseudonym public key Q PID =fZ'+Q V , and Q PID Return to RSU;

[0095] Step E5: RSU calculates K'=d R -1 U, recover the plaintext message m'=C⊕H2(U,K');

[0096] Step E6: RSU calculates e'=H1(m',K') and t'=(e'+x K' +s)modq, if t'≠0 and K'=sP+tQ PID , then output the decrypted message m, otherwise output the error symbol ⊥.

[0097] In one embodiment of the present invention, step F includes the following:

[0098] Step F1: The trusted center looks up the private key d of the current region AS AS , calculate Z'=d AS PID1, thereby obtaining the anonymous identity of the tracked vehicle AID=PID2⊕H1(PID1,Z');

[0099] Step F2: The trusted center searches for the corresponding certificate Recovering the true identity of tracked vehicles And the identity RID V Mark as illegal;

[0100] Step F3: The trusted center revokes the certificate from the smart contract

[0101] In one embodiment of the present invention, an SM2 signcryption system supporting rapid revocation in an in-vehicle network environment is provided, which is used to implement an SM2 signcryption method supporting rapid revocation in an in-vehicle network environment as described in any one of the present inventions. The SM2 signcryption system supporting rapid revocation in an in-vehicle network environment includes a system initialization module, a legal vehicle registration module, a vehicle pseudonym generation module, a message signcryption generation module, a message decryption verification module, and a tracking and revocation module.

[0102] The system initialization module is used to generate the system's global public parameter set and master key based on the input security parameters. Furthermore, the system initialization module initializes the roadside infrastructure and authentication server;

[0103] The legal vehicle registration module is used to identify the vehicle based on the system's global public parameter set. Furthermore, the trusted center is responsible for generating anonymous identities and implicit certificates for legal vehicles and uploading them to the smart contract in the blockchain.

[0104] The vehicle pseudonym generation module is used to generate its own pseudonym and corresponding private key based on the system's global public parameter set, the vehicle's identity and anonymous identity;

[0105] The message signcryption generation module is used to signcrypt the message based on the system's global public parameter set, the vehicle's private key and pseudonym, and the roadside infrastructure's public key, and send the signcryption result to the roadside infrastructure.

[0106] The message decryption and verification module is used to decrypt and verify the message signcryption result from the vehicle based on the system's global public parameter set, the vehicle's signcryption, and the roadside infrastructure's private key.

[0107] The tracking and revocation module is used to track the identity corresponding to the illegal vehicle pseudonym and revoke the vehicle based on the system's global public parameter set, the verification results of the roadside infrastructure, and the vehicle's pseudonym.

[0108] In one embodiment of the present invention, an SM2 signcryption system that supports rapid revocation in an in-vehicle network environment includes an electronic device, wherein the electronic device includes a memory, a processor, and a computer program stored in the memory and runnable on the processor, and is characterized in that when the processor executes the computer program, it implements an SM2 signcryption method that supports rapid revocation in an in-vehicle network environment as described in any one of the present inventions.

[0109] In one embodiment of the present invention, an SM2 signcryption system that supports rapid revocation in an in-vehicle network environment includes a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and is characterized in that when the computer program is executed by a processor, it implements an SM2 signcryption method that supports rapid revocation in an in-vehicle network environment as described in any one of the present inventions.

[0110] In one embodiment of the present invention, Figure 3 As shown in the comparison diagram of the computational time of each stage in the embodiment of the present invention, the computational time of the SM2 signcryption method and system supporting rapid revocation in a vehicle network environment provided by the present invention is better than that of a blockchain-assisted anonymous authentication protocol proposed by Feng et al., and is also better than that of a multi-signature protocol constructed by House et al.

[0111] The above are preferred embodiments of the present invention. Any changes made according to the technical solution of the present invention, as long as the resulting functions and effects do not exceed the scope of the technical solution of the present invention, shall fall within the scope of protection of the present invention.

Claims

1. An SM2 signcryption method supporting rapid revocation in a vehicle network environment, characterized in that: An SM2 signcryption system supporting rapid revocation is used, wherein the SM2 signcryption system includes a trusted center, roadside infrastructure, an authentication server, a vehicle, and a blockchain, wherein an SM2 signcryption method supporting rapid revocation in a vehicle network environment includes the following steps: Step A: Based on the security parameters and the trusted center, the system's global public parameter set and master key are generated and initialized for the roadside infrastructure and authentication server; Step B: Based on the system's global public parameter set, the vehicle's identity, and the trusted center, an anonymous identity and implicit certificate are generated for the legitimate vehicle and uploaded to the smart contract in the blockchain; Step C: Generate a pseudonym and corresponding private key for the vehicle based on the system's global public parameter set, the vehicle's identity and anonymous identity; Step D: Based on the system's global public parameter set, the vehicle's private key and pseudonym, and the roadside infrastructure's public key, the vehicle signencrypts the message and sends the signcrypted result to the roadside infrastructure. Step E: Based on the system's global public parameter set, the vehicle's signcryption information, and the roadside infrastructure's private key, the roadside infrastructure decrypts and verifies the message signcryption result from the vehicle. Step F: Based on the system's global public parameter set, the verification results of the roadside infrastructure, and the vehicle's pseudonym, the trusted center tracks the identity corresponding to the illegal vehicle pseudonym and revokes the vehicle.

2. The SM2 signcryption method supporting rapid revocation in a vehicle network environment according to claim 1, characterized in that: Step A includes the following: Step A1: The trusted center uses the security parameter λ∈Z q * , generate a prime number q of λ bits, a q-order elliptic curve group G, where Z q * is a set of positive integers; Step A2: The trusted center selects a generator P from the elliptic curve group G and randomly selects an integer d TA ∈Z q * As the system master private key, calculate the system master public key Q TA =d TA P; Step A3: The trusted center defines three hash functions H1: H2:G×G→{0,1} λ , H3: Where H1 is {0,1} * and elements in group G to set The hash function H2 is the sum of G and G to the set The hash function H3 is {0,1} * and To the collection The hash function of {0,1} * It is a set of binary symbol strings of variable length; Step A4: The trusted center compiles the smart contract and deploys it to the blockchain and returns the address scid of the smart contract.

3. The SM2 signcryption method supporting rapid revocation in a vehicle network environment according to claim 2, characterized in that: Step B includes the following: Step B1: Vehicle selection random number γ∈Z q * , calculate A=γPA=γP, and then transmit A and identity RID through the secure channel V ∈{0,1} * The identity is transmitted to the trusted center, which verifies the legitimacy of the identity. If it is not legal, the identity is rejected. Otherwise, step B2 is executed. Step B2: The trusted center randomly selects β∈Z q * ,calculate and Where AID is the anonymous identity of the vehicle; Step B3: Trusted Center Computation and Implicit Certificate and Return the certificate to the vehicle Upload to the smart contract in the blockchain; Step B4: Vehicle Calculation and Verify Q V =d V P, when the equality holds, the certificate is valid.

4. The SM2 signcryption method supporting rapid revocation in a vehicle network environment according to claim 3, characterized in that: Step C includes the following: Step C1: Vehicle randomly selects z∈Z q * , calculate Z = zP, pseudonym PID1 = zQ AS and PID2 = AID ⊕ H1 (PID1, Z); Step C2: The vehicle calculates the pseudonymous private key d PID =(z·f+d V ) mod q, where f = H2(PID2, Z); Step C3: The vehicle sends the pseudonym PID = (PID1, PID2) and the private key d PID Store for later use.

5. The SM2 signcryption method supporting rapid revocation in a vehicle network environment according to claim 4, characterized in that: Step D includes the following: Step D1: Vehicle randomly selects k∈Z q * , calculate K=kP=(x K ,y K ), e=H1(m,K) and r=(x K +e)modq, where the message m∈{0,1} λ If r+k=q or r=0, reselect k, otherwise execute step D2; Step D2: Vehicle calculation s=(1+d PID ) -1 (kd PID r) modq, if s≠0, then calculate U = kQ RSU and C=m⊕H2(U,K), otherwise terminate the program; Step D3: The vehicle signs the ciphertext as CT = (C, U, s), and sends CT, the anonymous identity PID, and the current timestamp ts to the infrastructure RSU through the wireless channel.

6. The SM2 signcryption method supporting rapid revocation in a vehicle network environment according to claim 5, characterized in that: Step E includes the following: Step E1: The RSU receives (CT, PID, ts) and checks whether the timestamp ts is fresh. If so, it sends a query request to the authentication server AS in the local area through a secure wired channel. Otherwise, it discards the message. Step E2: After receiving the query request, AS calculates Z'=d AS PID1 and AID = PID2 ⊕ H1 (PID1, Z'), retrieve the corresponding certificate from the blockchain Step E3: AS calculation And search the local database for the public key of the corresponding certificate If it exists, return it directly, otherwise calculate And (h',Q V ) is stored in the local database; Step E4: AS calculates f=H2(PID2,Z') and vehicle pseudonym public key Q PID =fZ'+Q V , and Q PID Return to RSU; Step E5: RSU calculates K'=d R -1 U, recover the plaintext message m'=C⊕H2(U,K'); Step E6: RSU calculates e'=H1(m',K') and t'=(e'+x K' +s)modq, if t'≠0 and K'=sP+tQ PID , then output the decrypted message m, otherwise output the error symbol ⊥.

7. The SM2 signcryption method supporting rapid revocation in a vehicle network environment according to claim 6, characterized in that: Step F includes the following: Step F1: The trusted center looks up the private key d of the current region AS AS , calculate Z'=d AS PID1, obtain the anonymous identity of the tracked vehicle AID = PID2 ⊕ H1 (PID1, Z'); Step F2: The trusted center searches for the corresponding certificate Recovering the true identity of tracked vehicles And the identity RID V Mark as illegal; Step F3: The trusted center revokes the certificate from the smart contract 8. An SM2 signcryption system supporting rapid revocation in an in-vehicle network environment, configured to execute the SM2 signcryption method supporting rapid revocation in an in-vehicle network environment as claimed in any one of claims 1 to 7, characterized in that: The SM2 signcryption system supporting rapid revocation in an in-vehicle network environment includes a system initialization module, a legal vehicle registration module, a vehicle pseudonym generation module, a message signcryption generation module, a message decryption verification module, and a tracking and revocation module: The system initialization module is used to generate the system's global public parameter set and master key based on the input security parameters. Furthermore, the system initialization module initializes the roadside infrastructure and authentication server; The legal vehicle registration module is used to identify the vehicle based on the system's global public parameter set. Furthermore, the trusted center is responsible for generating anonymous identities and implicit certificates for legal vehicles and uploading them to the smart contract in the blockchain. The vehicle pseudonym generation module is used to generate its own pseudonym and corresponding private key based on the system's global public parameter set, the vehicle's identity and anonymous identity; The message signcryption generation module is used to signcrypt the message based on the system's global public parameter set, the vehicle's private key and pseudonym, and the roadside infrastructure's public key, and send the signcryption result to the roadside infrastructure. The message decryption and verification module is used to decrypt and verify the message signcryption result from the vehicle based on the system's global public parameter set, the vehicle's signcryption, and the roadside infrastructure's private key. The tracking and revocation module is used to track the identity corresponding to the illegal vehicle pseudonym and revoke the vehicle based on the system's global public parameter set, the verification results of the roadside infrastructure, and the vehicle's pseudonym.

9. An SM2 signcryption system supporting rapid revocation in an in-vehicle network environment, comprising an electronic device, wherein the electronic device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the processor implements the SM2 signcryption method supporting rapid revocation in a vehicle network environment as described in any one of claims 1 to 7.

10. An SM2 signcryption system supporting rapid revocation in an in-vehicle network environment, comprising a computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the computer program implements the SM2 signcryption method supporting rapid revocation in a vehicle network environment as described in any one of claims 1 to 7.

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