Certificateless strong anonymous aggregation signcryption method in Internet of Vehicles

Abstract

The invention discloses a certificateless strong anonymous aggregation signcryption method in the Internet of Vehicles, and belongs to the technical field of information security. Based on a certificateless cryptosystem, the problems of certificate management and key escrow are effectively solved; a vehicle pseudonym autonomous dynamic updating mechanism based on pseudonym root parameters is designed, dependence of pseudonym updating on time is eliminated, a vehicle sends a registration application and a pseudonym activation application to different trusted mechanisms, the problem that the trusted mechanisms directly and independently restore the real identity of a vehicle user is solved, strong anonymity of the vehicle is guaranteed, and the reliability of the vehicle is improved. The public and private keys of the vehicle can be updated along with the update of the pseudonym, so that the forward security of the method is ensured; according to the aggregation signcryption method disclosed by the invention, a sender is allowed to perform encryption and signature operations on the message at the same time, and a verifier can verify a plurality of signatures at the same time, so that the calculation overhead in the signature generation and verification process is reduced while the message confidentiality is ensured; the method can effectively resist various attacks such as adaptive selection message attacks, adaptive selection ciphertext attacks, replay attacks and man-in-the-middle attacks, is low in calculation cost and low in communication overhead, and has a wide application prospect in the field of the Internet of Vehicles in which a large number of message signatures exist at the same time and message privacy needs to be protected.

Description

Technical Field

[0001] The present invention belongs to the field of information security technology, and specifically is a certificateless strong anonymous aggregate signcryption method in a connected vehicle network. Background Art

[0002] The Internet of Vehicles has brought many conveniences to the intelligent transportation system. However, the booming Internet of Vehicles faces many threats in terms of vehicle privacy protection and information security transmission, including but not limited to identity impersonation, message tampering, and vehicle user location tracking attacks. These threats may cause chaos in the traffic system and even endanger the personal safety of drivers. Therefore, ensuring the security and privacy of Internet of Vehicles communications has become a key research issue in the field of Internet of Vehicles.

[0003] Digital signature technology is an important authentication technology for verifying data integrity and ensuring the reliability of data sources, and is widely used in the Internet of Vehicles. However, in Internet of Vehicles communications, there are scenarios where multiple signatures need to be verified simultaneously. For this reason, aggregate signature technology can be used to improve the efficiency of signature verification. In addition, vehicles usually send information in the form of pseudonyms during communication to maintain a certain degree of anonymity to prevent the leakage of sensitive information such as the user's real identity.

[0004] However, the existing aggregate signature schemes still have certain limitations. In most aggregate signature schemes, messages are transmitted in plain text during the signature transmission process, and anyone can verify the signature, which will lead to the leakage of user privacy information; in the current anonymous schemes, multiple pseudonyms are applied for at one time or pseudonyms are updated at fixed time intervals, which leads to resource waste or excessive dependence on time factors for pseudonym updates; public and private keys are not adjusted accordingly with the update of pseudonyms, making it impossible to ensure the forward security of the scheme; when implementing conditional privacy protection, it completely relies on a trusted third party to track the true identity of the vehicle, which will also threaten the privacy of the vehicle. Summary of the invention

[0005] In view of the defects existing in the existing anonymous aggregate signature schemes in the Internet of Vehicles, the present invention provides a certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles.

[0006] The invention provides a certificateless strong anonymous aggregate signcryption method in a connected vehicle network, which is characterized by:

[0007] (1) The method allows the vehicle to dynamically update its pseudonym autonomously, eliminating the dependency of pseudonym update on time, and solves the problem of trusted institutions directly and independently restoring the real identity of the vehicle user, thus ensuring the strong anonymity of the vehicle;

[0008] (2) The method allows the vehicle user to encrypt and sign the message at the same time, so that the message is not sent in plain text during transmission, and the verifier can verify the signatures of multiple different users at the same time;

[0009] (4) The certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles includes five entities, namely a trusted authority (TA), a key generation center (KGC), a pseudonym activation authority (PA), a roadside unit (RSU) and a vehicle (V);

[0010] (5) The certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles includes the following ten steps:

[0011] S1: Initialization phase

[0012] The trusted authority TA and the key generation center KGC execute an initialization algorithm to generate system public parameters and a system master key, and publish the public parameters;

[0013] S2: Roadside Unit RSU Registration Phase

[0014] The roadside unit RSU sends a registration request message containing its real identity to the trusted institution TA, and the trusted institution TA verifies the legitimacy of the roadside unit RSU identity. If the verification is successful, TA generates its identity information in the Internet of Vehicles for the RSU and sends the identity information to the RSU and KGC;

[0015] S3: Roadside unit RSU public and private key generation stage

[0016] The roadside unit RSU sends its own vehicle networking identity information to the key generation center KGC. The KCG verifies the legitimacy of the vehicle networking identity information sent by the RSU based on the vehicle networking identity information of the RSU sent by the TA. If the verification is successful, the KGC generates a partial private key for the RSU based on the vehicle networking identity information of the RSU, and sends the partial private key to the RSU. The RSU calculates its own public key and private key based on the partial private key sent by the KGC.

[0017] S4: Vehicle V registration stage

[0018] Vehicle V sends a registration request message containing its real identity to the trusted institution TA. The trusted institution TA verifies the legitimacy of the real identity of vehicle V. If the verification is successful, it generates a pseudonym root parameter, a part of the private key generation parameter and a vehicle pseudonym verification parameter for the vehicle, encrypts the pseudonym root parameter and sends it to the vehicle, sends the vehicle pseudonym verification parameter to PA, and sends the part of the private key generation parameter to KGC.

[0019] S5: Vehicle V pseudonym activation stage

[0020] Vehicle V generates its own pseudonym based on the pseudonym root parameter generated by TA, and sends the pseudonym to the pseudonym activation agency PA. The pseudonym activation agency PA verifies the legitimacy of the pseudonym based on the vehicle pseudonym verification parameter. If the verification is successful, the pseudonym is added to the legal pseudonym pool, and a message of whether the pseudonym activation is successful is fed back to vehicle V;

[0021] S6: Vehicle V public and private key generation phase

[0022] Vehicle V calculates its own partial private key generation parameters based on the pseudonymous root parameters sent by TA, and sends them to the key generation center KGC. KCG verifies the legitimacy of the partial private key generation parameters sent by vehicle V based on the partial private key generation parameters sent by TA. If the verification is successful, KGC generates a partial private key for vehicle V based on the partial private key generation parameters, encrypts the partial private key and sends it to vehicle V. Vehicle V calculates its own public key and private key based on the partial private key sent by KGC.

[0023] S7: Broadcast communication stage

[0024] When the roadside unit RSU intends to broadcast a traffic message, the RSU signs the corresponding traffic message and broadcasts it to surrounding vehicles. The receiving vehicle V verifies the validity of the signature. If it is valid, the message is accepted, otherwise, the message is rejected.

[0025] S8: One-to-one communication stage

[0026] When vehicle V intends to communicate with a certain vehicle or roadside unit RSU in the Internet of Vehicles, the vehicle V signs and encrypts the message and sends it to the recipient. The recipient verifies the validity of the signature. If it is valid, the recipient restores the plain text to accept the message, otherwise, the recipient rejects the message.

[0027] S9: Vehicle V pseudonym and public and private key update phase

[0028] The vehicle updates its pseudonym and sends the updated pseudonym to the pseudonym activation agency PA. After the pseudonym activation agency PA verifies the legitimacy of the new pseudonym, it updates the pseudonym information corresponding to the vehicle in the pseudonym pool for other entities to check. At the same time, the vehicle user updates his own public key and private key after receiving the feedback message of successful activation;

[0029] S10: Malicious vehicle tracking stage

[0030] When a malicious vehicle releases false information, the receiving vehicle V or roadside unit RSU reports the malicious behavior of the vehicle to the trusted agency TA and the pseudonym activation agency PA and sends the pseudonym of the malicious vehicle. TA tracks the real identity of the malicious vehicle with the assistance of PA.

[0031] The certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles is characterized in that the five types of entities are specifically described as follows:

[0032] (1) Trusted Agency TA: The trusted agency TA is a trusted third party responsible for the registration of the vehicle V and the roadside unit RSU. It is the only entity that can identify the real identity of the vehicle. In specific scenarios, TA cooperates with PA to track the real identity of the malicious vehicle through the vehicle pseudonym.

[0033] (2) Key Generation Center KGC: The key generation center KGC is a trusted third party independent of the TA and is responsible for generating some private keys for vehicles and roadside units RSU;

[0034] (3) Pseudonym Activation Authority PA: The Pseudonym Activation Authority PA is a trusted entity under the jurisdiction of TA, responsible for activating and publishing vehicle pseudonyms and managing the update of the vehicle pseudonym pool;

[0035] (4) Roadside Unit (RSU): A roadside unit (RSU) is a road infrastructure deployed on the roadside. It is a semi-trusted entity with certain computing and storage capabilities. The RSU can collect traffic information within its range and broadcast it to nearby vehicles to improve traffic efficiency.

[0036] (5) Vehicle V: Vehicles in the Internet of Vehicles have limited computing and storage capabilities and can communicate with other entities through OBU (On-Board Unit) devices.

[0037] Furthermore, the certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles is characterized in that the system initialization phase in step S1 is specifically described as follows:

[0038] S11: Given a security parameter λ, the trusted authority TA and the key generation center KGC select an additive cyclic group G with a prime number q and a generator P according to λ; the trusted authority TA and the key generation center KGC select 6 hash functions H0~H5, where

[0039] S12: Trusted institution TA selects random number As its master private key, and calculate its public key T pub =tP;

[0040] S13: The key generation center KGC selects a random number As its master private key, and calculate its public key P pub =sP;

[0041] S14: The trusted authority TA and the key generation center KGC publish system parameters params={q,P,G,H0~H5,Tpub ,P pub}.

[0042] Furthermore, the method for strongly anonymous aggregate signcryption based on certificateless in the vehicle network is characterized in that in the roadside unit RSU registration phase in step S2, the roadside unit RSU i For example, the specific description is:

[0043] S21: Roadside Unit RSU i Your identity information Send to the trusted institution TA;

[0044] S22: The trusted institution TA receives After that, check Is it the first registration? If not, RSU will be rejected. i Registration request for RSU i Generate a connected car identity TA will Stored locally and Sent to RSU separately i and KGC.

[0045] Furthermore, the method for strong anonymous aggregate signcryption based on certificateless in the vehicle network is characterized in that in the step S3, the roadside unit RSU public and private key generation phase is based on the roadside unit RSU i For example, the specific description is:

[0046] S31: RSU i Will Send to KGC;

[0047] S32: KGC receives Then, find the PID in the local list RSUi Does it exist? If not, reject RSU i Otherwise, select a random number Calculate X i =x i P, Will Send to RSU i , and Delete from local list;

[0048] S33: RSU i receive After that, verify the equation Is it true? If not, discard the message; otherwise, select a random number As its own secret value, and calculate B i=b i P, RSU i Setting up private keys Public Key Simultaneous RSU i Make your own Published as a public parameter on the Internet of Vehicles.

[0049] Furthermore, the method for strong anonymous aggregate signcryption based on certificateless in the Internet of Vehicles is characterized in that in the vehicle V registration phase in step S4, the vehicle V i For example, the specific description is:

[0050] S41: Vehicle V i Pick a random number Calculate U i =u i P,TU i =u i T pub , And {R i ,U i} is sent to the trusted authority TA, where V i The true identity of

[0051] S42: The trusted institution TA receives {R i ,U i}, calculate TU i =tU i , examine Whether it is the first registration. If not, the service provider refuses to provide services to the vehicle. Otherwise, the provider selects a pseudonym root parameter for the vehicle. Calculate N i =n i P, The trusted institution TA will Stored in the local vehicle information table, and {PU i}Send to V i , the pseudonym verification parameter {N i ,U i}Send it to the pseudonym activation agency PA and generate some private key parameters Sent to the key generation center KGC.

[0052] Furthermore, the method for strong anonymous aggregate signcryption based on certificateless in the vehicle network is characterized in that in the vehicle V pseudonym activation phase in step S5, the vehicle V i For example, the specific description is:

[0053] S51: Vehicle V iReceived {PU generated by TA for it i}, calculate V i Pick a random number As its own secret value, calculate N i =n i P, and will Send to the pseudonym activation agency PA;

[0054] S52: Pseudonym activation agency PA receives vehicle V i Sent Then, find the local {N i ,U i} list, according to U i Find the corresponding N i , and verify the equation Is it true? If the equation is not true, then the vehicle V is rejected. i Otherwise, calculate Will Publish it in the legal pseudonym pool to facilitate other entities to check, and store {N i ,U i Updated to Finally, the message of whether the pseudonym activation is successful is fed back to the vehicle V i .

[0055] Furthermore, the method for strong anonymous aggregate signcryption based on certificateless in the Internet of Vehicles is characterized in that in the step S6, the vehicle V public and private key generation phase is based on the vehicle V i For example, the specific description is:

[0056] S61: Vehicle V i Calculate KU i =u i P pub , And {I i ,U i}Send to the key generation center KGC;

[0057] S62: The key generation center KGC receives {I i ,U i}, calculate KU i =sU i , and look in local listings If it does not exist, reject the vehicle V i Otherwise, select a random number Calculate Ki =k i P, {KPU i ,K i}Send to V i , and Remove from local list;

[0058] S63: Vehicle V i Received {KPU i ,K i}, calculate Verify the equation Is it true? If not, discard the message; otherwise, vehicle V i Setting up private keys Public Key

[0059] Furthermore, the method for strong anonymous aggregate signcryption based on certificateless in the Internet of Vehicles is characterized in that, in the broadcast communication phase in step S7, the sender RSU i and the receiver V r For example, the specific description is:

[0060] S71: RSU i Pick a random number Calculate D i =d i P, Generate signature σ i =(S i ,D i ), RSU i broadcast To surrounding vehicles;

[0061] S72: Vehicle V r Received After that, first check the timestamp T i Freshness, that is, according to T rev -T i ≤ΔT to judge T i Freshness, T rev is the receiving timestamp, ΔT is the maximum transmission delay, if the timestamp T i If it is valid, then execute steps S721-S722, otherwise, discard the message;

[0062] S721: Vehicle V r calculate

[0063] S722: Vehicle V r Verify the equation Is it true? If so, the signature is valid. Otherwise, the message is discarded.

[0064] S73: If the vehicle V r Receive messages from n different RSUs The receiver first checks n T i Freshness, discard invalid T i message, and for effective T i Message (i∈{1, 2, 3..., y}), execute steps S731-S733;

[0065] S731: V r calculate

[0066] S732: V r calculate

[0067] S733: V r Verify the equation Is it true? If so, it means that the y signatures are valid at the same time. Otherwise, verify the validity of the y signatures one by one.

[0068] Furthermore, the method for strong anonymous aggregate signcryption based on certificateless in the Internet of Vehicles is characterized in that in the one-to-one communication phase in step S8, the sender V i and the receiver V r For example, the specific description is:

[0069] S81: Sender vehicle V i Pick a random number calculate Generate signature σ i =(S i ,D i ,M i ), sender V i send Give V r ,in For the receiver V r alias, For the receiver V r 's public key;

[0070] S82: Receiving vehicle V r Received After that, check T i Is it effective and Is it a legal pseudonym? If the timestamp is T i Valid and If it is a legal pseudonym issued by PA, then record And execute steps S821-S823, otherwise, discard the message;

[0071] S821: V r calculate in For the receiver V r Part of the private key, For the receiver V r The secret value of

[0072] S822: V r calculate h 5i =H5(h 4i ,M i );

[0073] S823: V r Verify the equation Is it true? If true, the signature is valid and the plaintext is restored. Otherwise, discard the message;

[0074] S83: If the receiving vehicle V r Received different messages from n senders The receiver first checks n T i The validity of the T i Messages and effective T i message (i∈{1, 2, 3...., y}), execute steps S831-S834;

[0075] S831: V r calculate

[0076] S832: V r calculate

[0077] S833: V r calculate h 5i =H5(h 4i ,M i );

[0078] S834: V r Verify the equation Is it true? If it is true, it means that the signcryption of y sender vehicles is valid at the same time, and the plaintext is restored Otherwise, verify the validity of y signatures one by one.

[0079] Furthermore, the method for strong anonymous aggregate signcryption based on certificateless in the Internet of Vehicles is characterized in that in the vehicle pseudonym and public and private key update phase in step S9, the vehicle V i For example, the specific description is:

[0080] S91: Vehicle V i Pick a random number As its own secret value, calculate Will Send to the pseudonym activation agency PA;

[0081] S92: Pseudonym activation agency PA received Afterwards, according to In local list Find the corresponding N i ,U i , verify the equation Is it true? If not, reject vehicle V i Otherwise, calculate The information in the pseudonym pool Updated to Will store list information Updated to It is convenient for other entities to check and feedback whether the pseudonym activation is successful to the vehicle V i ;

[0082] S93: Vehicle V i Update its private key after receiving the activation success message Public Key

[0083] Furthermore, the method for strong anonymous aggregate signcryption based on certificateless in the Internet of Vehicles is characterized in that in the malicious vehicle tracking phase in step S10, the vehicle V i For example, the specific description is:

[0084] S101: The vehicle or roadside unit RSU that receives the false message reports the malicious vehicle V to the trusted agency TA and the pseudonym activation agency PA i Malicious behavior and V i pseudonym Send to TA and PA respectively;

[0085] S102: Pseudonym activation agency PA according to Find the storage list of itself Find with The corresponding Ni , and Send to the trusted institution TA;

[0086] S103: TA receives the data sent by PA Then, search for the N in its own storage list. i of Get a fake name with the vehicle The real identity of the corresponding vehicle And for malicious vehicles V i Carry out subsequent accountability.

[0087] Compared with the prior art, the certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles described in the present invention has the following beneficial effects:

[0088] The present invention discloses a certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles, which is designed based on a certificateless public key cryptography system and effectively solves the certificate management and key hosting problems; the aggregate signcryption method described in the present invention combines the signcryption mechanism with the aggregate signature mechanism, allowing the sender to encrypt and sign the message at the same time, and the verifier can verify multiple signatures at the same time, and provide non-repudiation services for multiple users and multiple messages at the same time, ensuring the confidentiality of the message while reducing the computational overhead in the signature generation and verification process; the present invention designs an autonomous dynamic update mechanism for vehicle pseudonyms based on pseudonym root parameters, eliminating the dependence of pseudonym updates on time, effectively solving the problem of trusted institutions directly and independently restoring the real identity of vehicle users, ensuring the strong anonymity of the vehicle, and the public and private keys of the vehicle will be updated with the update of the pseudonym, ensuring the forward security of the scheme. In addition, the third-party trusted institution encrypts the pseudonym root parameters and part of the private key and transmits them to the corresponding registrants in the form of ciphertext, eliminating the dependence of sensitive parameters on the secure channel during the transmission process. The present invention can effectively resist multiple types of attacks such as adaptive selected message attack, adaptive selected ciphertext attack, replay attack and man-in-the-middle attack, and has low computational cost and low communication overhead. It has broad application prospects in the field of Internet of Vehicles where a large number of message signatures exist at the same time and the privacy of messages needs to be protected. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] Figure 1 is a system architecture diagram of the present invention;

[0090] Figure 2 This is a flow chart of the initialization phase, roadside unit RSU registration and public and private key generation phases of an embodiment of the present invention;

[0091] Figure 3 This is a flow chart of the vehicle V registration, pseudonym activation and public and private key generation stages of an embodiment of the present invention;

[0092] Figure 4This is a flow chart of the broadcast communication phase of an embodiment of the present invention;

[0093] Figure 5 This is a flow chart of the one-to-one communication phase of an embodiment of the present invention. DETAILED DESCRIPTION

[0094] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0095] Embodiment 1:

[0096] like Figure 1 As shown, the certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles described in the present invention includes the following five entities:

[0097] (1) Trusted Agency TA: The trusted agency TA is a trusted third party responsible for the registration of the vehicle V and the roadside unit RSU. It is the only entity that can identify the real identity of the vehicle. In specific scenarios, TA cooperates with PA to track the real identity of the malicious vehicle through the vehicle pseudonym.

[0098] (2) Key Generation Center KGC: The key generation center KGC is a trusted third party independent of the TA and is responsible for generating some private keys for vehicles and roadside units RSU;

[0099] (3) Pseudonym Activation Authority PA: The Pseudonym Activation Authority PA is a trusted entity under the jurisdiction of TA, responsible for activating and publishing vehicle pseudonyms and managing the update of the vehicle pseudonym pool;

[0100] (4) Roadside Unit (RSU): A roadside unit (RSU) is a road infrastructure deployed on the roadside. It is a semi-trusted entity with certain computing and storage capabilities. The RSU can collect traffic information within its range and broadcast it to nearby vehicles to improve traffic efficiency.

[0101] (5) Vehicle V: Vehicles in the Internet of Vehicles have limited computing and storage capabilities and can communicate with other entities through OBU (On-Board Unit) devices.

[0102] The present invention provides a certificateless strong anonymous aggregate signcryption method in a connected vehicle network, which includes the following ten steps:

[0103] S1: Initialization phase

[0104] The trusted authority TA and the key generation center KGC execute the initialization algorithm to generate system public parameters and system master key, and publish the public parameters. The initialization phase is as follows: Figure 2 As shown in steps ①~②;

[0105] Furthermore, S1 includes S11 to S14, which are specifically described as follows:

[0106] S11: Given a security parameter λ, the trusted authority TA and the key generation center KGC select an additive cyclic group G with a prime number q and a generator P according to λ; the trusted authority TA and the key generation center KGC select 6 hash functions H0~H5, where

[0107] S12: Trusted institution TA selects random number As its master private key, and calculate its public key T pub =tP;

[0108] S13: The key generation center KGC selects a random number As its master private key, and calculate its public key P pub =sP;

[0109] S14: The trusted authority TA and the key generation center KGC publish system parameters params={q,P,G,H0~H5,T pub ,P pub}.

[0110] S2: Roadside Unit RSU Registration Phase

[0111] The roadside unit RSU sends a registration request message containing its real identity to the trusted institution TA. The trusted institution TA verifies the legitimacy of the roadside unit RSU identity. If the verification is successful, TA generates its identity information in the Internet of Vehicles for the RSU and sends the identity information to the RSU and KGC. The roadside unit RSU registration phase is as follows: Figure 2 As shown in steps ③~⑤;

[0112] Further, S2 includes S21 to S22, with roadside unit RSU i For example, the specific description is:

[0113] S21: Roadside Unit RSU i Your identity information Send to the trusted institution TA;

[0114] S22: The trusted institution TA receives After that, check Is it the first registration? If not, RSU will be rejected. i Registration request for RSU i Generate a connected car identity TA will Stored locally and Sent to RSU separately i and KGC.

[0115] S3: Roadside unit RSU public and private key generation stage

[0116] The roadside unit RSU sends its own vehicle networking identity information to the key generation center KGC. KCG verifies the legitimacy of the vehicle networking identity information sent by the RSU based on the vehicle networking identity information of the RSU sent by TA. If the verification is successful, KGC generates a partial private key for the RSU based on the RSU vehicle networking identity information and sends the partial private key to the RSU. The RSU calculates its own public key and private key based on the partial private key sent by KGC. The roadside unit RSU public and private key generation stage is as follows: Figure 2 As shown in steps ⑥~⑨;

[0117] Further, S3 includes S31 to S33, with roadside unit RSU i For example, the specific description is:

[0118] S31: RSU i Will Send to KGC;

[0119] S32: KGC receives Then search in the local list Does it exist? If not, reject RSU i Otherwise, select a random number Calculate X i =x i P, Will Send to RSU i , and Delete from local list;

[0120] S33: RSU i receive After that, verify the equation Is it true? If not, discard the message; otherwise, select a random number As its own secret value, and calculate B i =b i P, RSU i Setting up private keys Public Key Simultaneous RSU i Make your own Published as a public parameter on the Internet of Vehicles.

[0121] S4: Vehicle V registration stage

[0122] Vehicle V sends a registration request message containing its real identity to the trusted institution TA. The trusted institution TA verifies the legitimacy of the real identity of vehicle V. If the verification is successful, it generates a pseudonym root parameter, a partial private key generation parameter and a vehicle pseudonym verification parameter for the vehicle, encrypts the pseudonym root parameter and sends it to the vehicle, sends the vehicle pseudonym verification parameter to PA, and sends the vehicle partial private key generation parameter to KGC. The vehicle V registration stage is as follows: Figure 3 As shown in steps ①~④;

[0123] Further, S4 includes S41 to S42, with the vehicle V i For example, the specific description is:

[0124] S41: Vehicle V i Pick a random number Calculate U i =u i P,TU i =u i T pub , And {R i ,U i} is sent to the trusted authority TA, where V i The true identity of

[0125] S42: The trusted institution TA receives {R i ,U i}, calculate TU i =tU i , examine Whether it is the first registration. If not, the service provider refuses to provide services to the vehicle. Otherwise, the provider selects a pseudonym root parameter for the vehicle. Calculate N i =n i P, The trusted institution TA will Stored in the local vehicle information table, and {PU i}Send to V i , the pseudonym verification parameter {N i ,U i}Send it to the pseudonym activation agency PA and generate some private key parameters Send to the key generation center KGC;

[0126] In step S42, the trusted authority TA uses TU i For the vehicle V i The pseudonymous root parameter and part of the private key generation parameter are encrypted, and then sent to the vehicle V in ciphertext form. iTransmitting its own pseudonymous root parameters and some private key generation parameters eliminates the dependence of sensitive parameter transmission on secure channels.

[0127] S5: Vehicle V pseudonym activation stage

[0128] Vehicle V generates its own pseudonym based on the pseudonym root parameter generated by TA, and sends the pseudonym to the pseudonym activation mechanism PA. The pseudonym activation mechanism PA verifies the legitimacy of the pseudonym based on the vehicle pseudonym verification parameter. If the verification is successful, the pseudonym is added to the legal pseudonym pool, and the message of whether the pseudonym activation is successful is fed back to vehicle V. The pseudonym activation stage of vehicle V is as follows: Figure 3 As shown in steps ⑤~⑦;

[0129] Further, S5 includes S51 to S52, with the vehicle V i For example, the specific description is:

[0130] S51: Vehicle V i Received {PU generated by TA for it i}, calculate V i Pick a random number As its own secret value, calculate N i =n i P, and will Send to the pseudonym activation agency PA;

[0131] S52: Pseudonym activation agency PA receives vehicle V i Sent Then, find the local {N i ,U i} list, according to U i Find the corresponding N i , and verify the equation Is it true? If the equation is not true, then the vehicle V is rejected. i Otherwise, calculate Will Publish it in the legal pseudonym pool to facilitate other entities to check, and store {N i ,U i Updated to Finally, the message of whether the pseudonym activation is successful is fed back to the vehicle V i .

[0132] S6: Vehicle V public and private key generation phase

[0133] Vehicle V calculates its own partial private key generation parameters based on the pseudonymous root parameters sent by TA, and sends them to the key generation center KGC. KCG verifies the legitimacy of the partial private key generation parameters sent by vehicle V based on the partial private key generation parameters sent by TA. If the verification is successful, KGC generates a partial private key for vehicle V based on the partial private key generation parameters, encrypts the partial private key and sends it to vehicle V. Vehicle V calculates its own public key and private key based on the partial private key sent by KGC. The public and private key generation stage of vehicle V is as follows: Figure 3 Step ⑧~ As shown;

[0134] Further, S6 includes S61 to S63, with the vehicle V i For example, the specific description is:

[0135] S61: Vehicle V i Calculate KU i =u i P pub , And {I i ,U i}Send to the key generation center KGC;

[0136] S62: The key generation center KGC receives {I i ,U i}, calculate KU i =sU i , and look for it in the local list If it does not exist, reject the vehicle V i Otherwise, select a random number Calculate K i =k i P, {KPU i ,K i}Send to V i , and Remove from local list;

[0137] S63: Vehicle V i Received {KPU i ,K i}, calculate Verify the equation Is it true? If not, discard the message; otherwise, vehicle V i Setting up private keys Public Key

[0138] In step S62, the key generation center KGC uses KU iFor the vehicle V i The vehicle V is encrypted with a part of the private key and then sent to the vehicle V in ciphertext form. i Transmit part of its own private key, which eliminates the dependence of sensitive parameter transmission on secure channels;

[0139] In step S63, the vehicle V i The public and private keys are calculated based on the partial private key sent by the key generation center KGC, thus solving the certificate management and key trusteeship problems.

[0140] S7: Broadcast communication stage

[0141] When the roadside unit RSU intends to broadcast a traffic message, the RSU signs the corresponding traffic message and broadcasts it to surrounding vehicles. The receiving vehicle V verifies the validity of the signature. If it is valid, the message is accepted. Otherwise, the message is rejected. The broadcast communication stage is as follows: Figure 4 As shown in steps ①~⑤;

[0142] Further, S7 includes S71 to S73, with the sender RSU i and the receiver V r For example, the specific description is:

[0143] S71: RSU i Pick a random number Calculate D i =d i P, Generate signature σ i =(S i ,D i ), RSU i broadcast To surrounding vehicles;

[0144] S72: Vehicle V r Received After that, first check the timestamp T i Freshness, that is, according to T rev -T i ≤ΔT to judge T i Freshness, T rev is the receiving timestamp, ΔT is the maximum transmission delay, if the timestamp T i If it is valid, then execute steps S721-S722, otherwise discard the message;

[0145] S721: Vehicle V r calculate

[0146] S722: Vehicle V r Verify the equation Is it true? If so, the signature is valid. Otherwise, the message is discarded.

[0147] S73: If the vehicle V r Receive messages from n different RSUs The receiver first checks n T i Freshness, discard invalid T i message, and for effective T i Message (i∈{1, 2, 3..., y}), execute steps S731-S733;

[0148] S731: V r calculate

[0149] S732: V r calculate

[0150] S733: V r Verify the equation Is it true? If so, it means that the y signatures are valid at the same time. Otherwise, verify the validity of the y signatures one by one.

[0151] S8: One-to-one communication stage

[0152] When vehicle V intends to communicate with a certain vehicle or roadside unit RSU in the Internet of Vehicles, the vehicle V signs the message and sends it to the recipient. The recipient verifies the validity of the signature. If it is valid, the recipient restores the plain text to accept the message. Otherwise, the recipient rejects the message. The one-to-one communication stage is as follows: Figure 5 As shown in steps ①~⑤;

[0153] Further, S8 includes S81 to S83, with the sender V i and the receiver V r For example, the specific description is:

[0154] S81: Sender vehicle V i Pick a random number calculate h 5i =H5(h 4i ,M i ), Generate signature σ i =(S i ,D i ,M i ), sender V i send Give V r ,in For the receiver V r alias, For the receiver V r 's public key;

[0155] S82: Receiving vehicle V r Received After that, check T i Is it effective and Is it a legal pseudonym? If the timestamp is T i Valid and If it is a legal pseudonym issued by PA, then record And execute steps S821-S823, otherwise, discard the message;

[0156] S821: V r calculate in For the receiver V r Part of the private key, For the receiver V r The secret value of

[0157] S822: V r calculate h 5i =H5(h 4i ,M i );

[0158] S823: V r Verify the equation Is it true? If true, the signature is valid and the plaintext is restored. Otherwise, discard the message;

[0159] S83: If the receiving vehicle V r Received different messages from n senders The receiver first checks n T i The validity of the T i Messages and effective T i message (i∈{1, 2, 3...., y}), execute steps S831-S834;

[0160] S831: V r calculate

[0161] S832: V r calculate

[0162] S833: V r calculate

[0163] S834: V r Verify the equation Is it true? If it is true, it means that the signcryption of y sender vehicles is valid at the same time, and the plaintext is restored Otherwise, verify the validity of y signatures one by one;

[0164] In step S81, the sending vehicle V i Select the designated recipient V r , and use the specified recipient V r The signature and ciphertext are calculated based on the public key, pseudonym and other parameters, realizing the synchronous calculation of encryption and signature, and only the designated recipient can verify the signature and restore the plaintext.

[0165] S9: Vehicle V pseudonym and public and private key update phase

[0166] The vehicle updates its pseudonym and sends the updated pseudonym to the pseudonym activation agency PA. After the pseudonym activation agency PA verifies the legitimacy of the new pseudonym, it updates the pseudonym information corresponding to the vehicle in the pseudonym pool for other entities to check. At the same time, the vehicle user updates his own public key and private key after receiving the feedback message of successful activation;

[0167] Further, S9 includes S91 to S93, with the vehicle V i For example, the specific description is:

[0168] S91: Vehicle V i Pick a random number As its own secret value, calculate Will Send to the pseudonym activation agency PA;

[0169] S92: Pseudonym activation agency PA received Afterwards, according to In local list Find the corresponding N i ,U i , verify the equation Is it true? If not, reject vehicle V i Otherwise, calculate The information in the pseudonym pool Updated to Will store list information Updated to It is convenient for other entities to check and feedback whether the pseudonym activation is successful to the vehicle V i ;

[0170] S93: Vehicle V i Update its private key after receiving the activation success message Public Key

[0171] In step S91, the vehicle V i By reselecting random numbers Computationally generate new pseudonyms Autonomous dynamic pseudonym update is achieved.

[0172] S10: Malicious vehicle tracking stage

[0173] When a malicious vehicle releases false information, the receiving vehicle V or roadside unit RSU reports the malicious behavior of the vehicle to the trusted agency TA and the pseudonym activation agency PA and sends the pseudonym of the malicious vehicle. TA tracks the real identity of the malicious vehicle with the assistance of PA.

[0174] Further, S10 includes S101 to S103, with the malicious vehicle V i For example, the specific description is:

[0175] S101: The vehicle or roadside unit RSU that receives the false message reports the malicious vehicle V to the trusted agency TA and the pseudonym activation agency PA i Malicious behavior and V i pseudonym Send to TA and PA respectively;

[0176] S102: Pseudonym activation agency PA according to Find the storage list of itself Find with The corresponding N i , and Send to the trusted institution TA;

[0177] S103: TA receives the data sent by PA Then, search for the N in its own storage list. i of Get a fake name with the vehicle The corresponding vehicle's real identity RID Vi , and the malicious vehicle V i Conduct follow-up accountability;

[0178] In step S10, the trusted institution TA and the pseudonym activation institution PA cooperate to track the real identity of the malicious vehicle, thereby preventing the trusted institution from independently restoring the user pseudonym.

[0179] A certificateless strong anonymous aggregate signcryption method in a connected vehicle network using the embodiment of the present invention described above in conjunction with the accompanying drawings is used to provide a secure and efficient communication environment for the connected vehicle network. However, the present invention is not limited to the described implementations, and these changes, modifications, substitutions and deformations to the implementations without departing from the principles and spirit of the present invention still fall within the protection scope of the present invention.

Claims

1. A certificateless strong anonymous aggregate signcryption method in a vehicle network, characterized by: (1) The method allows the vehicle to dynamically update its pseudonym autonomously, eliminating the dependency of pseudonym update on time, and solves the problem of trusted institutions directly and independently restoring the real identity of the vehicle user, thus ensuring the strong anonymity of the vehicle; (2) The method allows the vehicle user to encrypt and sign the message at the same time, so that the message is not sent in plain text during transmission, and the verifier can verify the signatures of multiple different users at the same time; (3) The certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles includes five entities, namely a trusted authority (TA), a key generation center (KGC), a pseudonym activation authority (PA), a roadside unit (RSU) and a vehicle (V); (4) The certificateless strong anonymous aggregate signcryption method in the Internet of Vehicles includes the following ten steps: S1: Initialization phase The trusted authority TA and the key generation center KGC execute an initialization algorithm to generate system public parameters and a system master key, and publish the public parameters; S2: Roadside unit RSU registration phase The roadside unit RSU sends a registration request message containing its real identity to the trusted institution TA, and the trusted institution TA verifies the legitimacy of the roadside unit RSU identity. If the verification is successful, TA generates its identity information in the Internet of Vehicles for the RSU and sends the identity information to the RSU and KGC; S3: Roadside unit RSU public and private key generation stage The roadside unit RSU sends its own vehicle networking identity information to the key generation center KGC. The KCG verifies the legitimacy of the vehicle networking identity information sent by the RSU based on the vehicle networking identity information of the RSU sent by the TA. If the verification is successful, the KGC generates a partial private key for the RSU based on the vehicle networking identity information of the RSU, and sends the partial private key to the RSU. The RSU calculates its own public key and private key based on the partial private key sent by the KGC. S4: Vehicle V registration stage Vehicle V sends a registration request message containing its real identity to the trusted institution TA. The trusted institution TA verifies the legitimacy of the real identity of vehicle V. If the verification is successful, it generates a pseudonym root parameter, a part of the private key generation parameter and a vehicle pseudonym verification parameter for the vehicle, encrypts the pseudonym root parameter and sends it to the vehicle, sends the vehicle pseudonym verification parameter to PA, and sends the part of the private key generation parameter to KGC. S5: Vehicle V pseudonym activation stage Vehicle V generates its own pseudonym based on the pseudonym root parameter generated by TA, and sends the pseudonym to the pseudonym activation agency PA. The pseudonym activation agency PA verifies the legitimacy of the pseudonym based on the vehicle pseudonym verification parameter. If the verification is successful, the pseudonym is added to the legal pseudonym pool, and a message of whether the pseudonym activation is successful is fed back to vehicle V; S6: Vehicle V public and private key generation phase Vehicle V calculates its own partial private key generation parameters based on the pseudonymous root parameters sent by TA, and sends them to the key generation center KGC. KCG verifies the legitimacy of the partial private key generation parameters sent by vehicle V based on the partial private key generation parameters sent by TA. If the verification is successful, KGC generates a partial private key for vehicle V based on the partial private key generation parameters, encrypts the partial private key and sends it to vehicle V. Vehicle V calculates its own public key and private key based on the partial private key sent by KGC. S7: Broadcast communication phase When the roadside unit RSU intends to broadcast a traffic message, the RSU signs the corresponding traffic message and broadcasts it to surrounding vehicles. The receiving vehicle V verifies the validity of the signature. If it is valid, the message is accepted, otherwise, the message is rejected. S8: One-to-one communication stage When vehicle V intends to communicate with a certain vehicle or roadside unit RSU in the Internet of Vehicles, the vehicle V signs and encrypts the message and sends it to the recipient. The recipient verifies the validity of the signature. If it is valid, the recipient restores the plain text to accept the message, otherwise, the recipient rejects the message. S9: Vehicle V pseudonym and public and private key update phase The vehicle updates its pseudonym and sends the updated pseudonym to the pseudonym activation agency PA. After the pseudonym activation agency PA verifies the legitimacy of the new pseudonym, it updates the pseudonym information corresponding to the vehicle in the pseudonym pool for other entities to check. At the same time, the vehicle user updates his own public key and private key after receiving the feedback message of successful activation; S10: Malicious vehicle tracking stage When a malicious vehicle releases false information, the receiving vehicle V or roadside unit RSU reports the malicious behavior of the vehicle to the trusted agency TA and the pseudonym activation agency PA and sends the pseudonym of the malicious vehicle. TA tracks the real identity of the malicious vehicle with the assistance of PA.

2. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: The five types of entities are specifically described as follows: (1) Trusted Agency TA: The trusted agency TA is a trusted third party responsible for the registration of vehicle V and roadside unit RSU. In specific scenarios, TA cooperates with PA to track the real identity of malicious vehicles through vehicle pseudonyms; (2) Key Generation Center KGC: The key generation center KGC is a trusted third party independent of the TA and is responsible for generating some private keys for vehicles and roadside units RSU; (3) Pseudonym Activation Agency : Pseudonym Activation Agency As a trusted entity under the jurisdiction of TA, it is responsible for the activation and publication of vehicle pseudonyms and manages the update of the vehicle pseudonym pool; (4) Roadside Unit (RSU): A roadside unit (RSU) is a road infrastructure deployed on the roadside. It is a semi-trusted entity with certain computing and storage capabilities. The RSU can collect traffic information within its range and broadcast it to nearby vehicles to improve traffic efficiency. (5) Vehicle V: Vehicles in the Internet of Vehicles have limited computing and storage capabilities and can communicate with other entities through OBU (On-Board Unit) devices.

3. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: The system initialization phase in step S1 is specifically described as follows: S11: Given safety parameters , the trusted authority TA and the key generation center KGC according to Choose the order to be a prime number , the generator is The additive cyclic group of ; The trusted authority TA and the key generation center KGC select 6 hash functions ,in , , , , , ; S12: Trusted Institutions Pick a random number As its master private key, and calculate its public key ; S13: The key generation center KGC selects a random number As its master private key, and calculate its public key ; S14: The trusted authority TA and the key generation center KGC publish system parameters in the Internet of Vehicles .

4. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: In the step S2, the roadside unit RSU registration phase is based on the roadside unit For example, the specific description is: S21: Roadside unit Your identity information Send to the trusted institution TA; S22: The trusted institution TA receives After that, check Is it the first registration? If not, reject. Request for registration; Otherwise Generate a connected car identity = , TA will Stored locally and Send to and KGC.

5. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: The step S3 is the RSU public and private key generation phase, with the RSU For example, the specific description is: S31: Will Send to KGC; S32: KGC receives Then search in the local list If it does not exist, reject it. Otherwise, select a random number ,calculate , ,Will Send to , and Delete from local list; S33: receive After that, verify the equation Is it true? If not, discard the message; Otherwise, pick a random number , as its own secret value, and calculate , Setting up private keys , public key ,at the same time Put your own } is published as a public parameter in the Internet of Vehicles.

6. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: In the vehicle V registration phase in step S4, the vehicle For example, the specific description is: S41: Vehicles Pick a random number ,calculate , , ⊕ , and Sent to a trusted institution TA, where for The true identity of S42: The trusted institution TA receives After that, calculate ,examine Whether it is the first registration. If not, the service provider refuses to provide services to the vehicle. Otherwise, the provider selects a pseudonym root parameter for the vehicle. ,calculate , = , , the trusted institution TA will Stored in the local vehicle information table and Send to , the pseudonym verification parameter Sent to the pseudonym activation agency PA, generating some private key parameters Sent to the key generation center KGC.

7. A certificateless strong anonymous aggregate signcryption method in a connected vehicle network according to claim 1, characterized in that: In the step S5, the vehicle V pseudonym activation stage is performed with the vehicle For example, the specific description is: S51: Vehicle Received the TA generated for it After that, calculate = Pick a random number , as its own secret value, calculate , and Send to the pseudonym activation agency PA; S52: Pseudonymous activation agency PA receives vehicle Sent Then, find the local List, according to Find the corresponding , and verify the equation Is it true? If the equation is not true, the vehicle is rejected. Otherwise, calculate ,Will Publish it in the legal pseudonym pool to facilitate other entities to check, and store it in the local storage list Updated to Finally, the vehicle is informed whether the pseudonym activation is successful. .

8. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: In step S6, the vehicle V public and private key generation phase is based on the vehicle For example, the specific description is: S61: Vehicles calculate and will Send to the key generation center KGC; S62: The key generation center KGC receives After that, calculate , and look for it in the local list If it does not exist, reject the vehicle Otherwise, select a random number ,calculate , ,Will Send to , and Remove from local list; S63: Vehicles receive After that, calculate , verify the equation Is it true? If not, the message is discarded; otherwise, the vehicle Setting up private keys , public key .

9. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: In the broadcast communication phase of step S7, the sender For and the recipient For example, the specific description is: S71: Pick a random number ,calculate , , , generate a signature , broadcast To surrounding vehicles; S72: Vehicles Received After that, first check the timestamp Freshness, that is, according to To judge Freshness, including To receive the timestamp, is the maximum transmission delay, if the timestamp If it is valid, then execute steps S721-S722, otherwise, discard the message; S721: Vehicle calculate ; S722: Vehicle Verify the equation Is it true? If so, the signature is valid. Otherwise, the message is discarded. S73: If the vehicle Receive messages from n different RSUs ( ), the receiver first checks n Freshness, discard invalid Messages and effective News( ), execute steps S731-S733; S731: calculate ; S732: calculate ; S733: Verify the equation Is it true? If so, it means that the y signatures are valid at the same time. Otherwise, verify the validity of the y signatures one by one.

10. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: In the one-to-one communication phase in step S8, the sender and the receiver For example, the specific description is: S81: Sender's vehicle Pick a random number ,calculate , , , , , , generate a signature , sender send Give ,in For the receiver 's pseudonym, For the receiver 's public key; S82: Receiving vehicle Received After that, check Is it effective and Is it a legal pseudonym? If the timestamp Valid and If it is a legal pseudonym issued by PA, then record And execute steps S821-S823, otherwise, discard the message; S821: calculate ,in For the receiver Part of the private key, For the receiver The secret value of S822: calculate ; S823: Verify the equation Is it true? If true, the signature is valid and the plaintext is restored. , otherwise, discard the message; S83: If the receiving vehicle Received different messages from n senders ( ), the receiver first checks n The validity of the Messages and effective News( ), execute steps S831-S834; S831: calculate ; S832: calculate ; S833: calculate ; S834: Verify the equation Is it true? If it is true, it means that the signcryption of y sender vehicles is valid at the same time, and the plaintext is restored , otherwise, verify the validity of y signatures one by one.

11. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: In the vehicle pseudonym and public and private key update phase in step S9, the vehicle For example, the specific description is: S91: Vehicle Pick a random number , as its own secret value, calculate ,Will Send to the pseudonym activation agency PA; S92: Pseudonym activation agency PA received Afterwards, according to In local list Find the corresponding , verify the equation Is it true? If not, reject the vehicle. Otherwise, calculate The information in the pseudonym pool Updated to , will store the list information Updated to , which is convenient for other entities to check and feedback to the vehicle whether the pseudonym activation is successful ; S93: Vehicle Update its private key after receiving the activation success message , public key .

12. A certificateless strong anonymous aggregate signcryption method in a vehicle network according to claim 1, characterized in that: In the malicious vehicle tracking phase in step S10, the malicious vehicle For example, the specific description is: S101: The vehicle or roadside unit RSU that receives the false message reports the malicious vehicle to the trusted agency TA and the pseudonym activation agency PA malicious behavior, and pseudonym Send to TA and PA respectively; S102: Pseudonym activation agency PA according to Find the storage list of itself , find Corresponding , and Send to the trusted institution TA; S103: TA receives the data sent by PA Then, search for the content in its own storage list. of , get the vehicle pseudonym The real identity of the corresponding vehicle , and for malicious vehicles Carry out subsequent accountability.

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