Privacy protection and dynamic certificateless group key negotiation method in unmanned aerial vehicle network

Abstract

The invention discloses a privacy protection and dynamic certificateless group key negotiation method in an unmanned aerial vehicle network, and the method comprises the steps: generating public and private keys based on a key generation center and a trusted registration mechanism, and constructing an unmanned aerial vehicle network password system; the unmanned aerial vehicle obtains the temporary pseudonym and the partial private key to generate a complete key pair; selecting a group manager, and completing symmetric and asymmetric group key negotiation through interaction; generating a symmetric group key and an asymmetric group key for intra-group communication and off-group communication respectively; and when the unmanned aerial vehicle joins in or leaves the group, dynamically updating the group key. The symmetric group key negotiation mechanism and the asymmetric group key negotiation mechanism provided by the invention support dynamic key updating when the unmanned aerial vehicle joins or leaves, so that privacy protection of the unmanned aerial vehicle and traceability of the malicious unmanned aerial vehicle can be realized; and various security characteristics such as anonymity, complete forward and backward security and temporary information security of a known specific session are met, and various security requirements of an unmanned aerial vehicle network can be greatly met.

Description

Technical Field

[0001] The present invention relates to the technical field of key negotiation, and in particular to a privacy protection and dynamic certificateless group key negotiation method in a drone network. Background Art

[0002] With the rapid development of artificial intelligence and the Internet of Things, drones are increasingly being used in multiple industries, especially in environmental monitoring, disaster response, and smart cities. Artificial intelligence improves drones' autonomous decision-making capabilities, while the Internet of Things enables them to connect seamlessly with a variety of devices. However, despite the huge potential of drones, they still face limitations in computing power and communication capabilities, as well as increasingly severe security challenges.

[0003] Drone networks are usually faced with large-scale dynamics and high decentralization. How to ensure secure communication between different devices and drones is a key issue. Although the existing key management scheme based on public key infrastructure can provide a certain degree of security, it cannot meet the needs of high dynamics and large-scale interactions in drone networks due to the complexity of certificate management and key hosting. In addition, as more devices (such as smartphones and wearable devices) interact with drone networks, how to effectively protect sensitive information, ensure privacy, and prevent identity forgery and data leakage are the core issues that need to be urgently addressed in the current drone network security. Especially in the interaction of multiple devices and large-scale dynamic drone groups, how to ensure the security and efficiency of data transmission and prevent internal data leakage, tampering or abuse has become a core issue in improving drone network security. In view of the privacy protection and secure data interaction problems of drone groups, a privacy protection and dynamic certificateless group key negotiation method suitable for drone networks is needed. Summary of the invention

[0004] The purpose of the present invention is to provide a privacy protection and dynamic certificateless group key negotiation method in a drone network.

[0005] To achieve the above object, the present invention is implemented according to the following technical solutions: The present invention comprises the following steps: Generate public and private keys based on the key generation center and trusted registration agency to build a drone network cryptography system; The drone obtains a temporary pseudonym and part of the private key to generate a complete key pair; Select a group manager and complete symmetric and asymmetric group key negotiation through interaction; Generate a symmetric group key and an asymmetric group key for intra-group and extra-group communications respectively; When a drone joins or leaves the group, the group key is dynamically updated.

[0006] Furthermore, the key generation center selects an additive cyclic group, a multiplicative cyclic group and a generator, selects a bilinear pairing operation and a hash function, and generates a system public and private key; The trusted registration authority selects a private key, calculates a public key, and sends it to the key generation center through a secure channel; Furthermore, when a drone user registers, the drone receives the system’s public parameters, selects secret values, calculates a partial public key, and sends a pseudonym request to the trusted registration authority; The trusted registration authority receives the request and checks whether the drone is legal. If it is legal, it calculates the temporary value, sets a temporary pseudonym, generates a partial private key request and sends it to the key generation center. The key generation center receives the request, selects a random number, calculates a partial public key and digest value, generates a partial private key and sends it back to the drone; The drone receives a partial private key reply and verifies it through a hash function. If the verification is successful, the complete public and private key pair is generated. Otherwise, a new pseudonym is applied for.

[0007] Furthermore, during group key negotiation, the group manager initiates a group key negotiation request, generates an identity ring, selects a random number as a group key negotiation identifier, and broadcasts group key initiation information; The group member receives the group key initiation information, selects a random number, calculates the random value, and sends it to the previous drone through the public channel; The group members receive the random number, calculate the summary value and temporary value, generate the message verification code, and send the authentication information through the public channel; The group manager receives the authentication information, calculates the group key, and broadcasts the group key negotiation information; The group members receive the group key negotiation information and generate a symmetric group key and an asymmetric group key.

[0008] Furthermore, the key generation method for the drone joining includes: The group manager announces the group member joining information, generates a new identity ring, and broadcasts the group key initiation information; The new member receives the group key initiation message, selects a random number, calculates the random number, and sends it to the previous user through a public channel; The group members receive the random number, calculate the summary value and temporary value, generate the message verification code, and send the authentication information through the public channel; The group manager receives the authentication information, calculates the group key, and broadcasts the group key negotiation information; The group members receive the group key agreement information and generate new symmetric group keys and asymmetric group keys.

[0009] Furthermore, the key generation method when the drone leaves includes: The group manager generates a new identity ring and broadcasts the group key initiation information; The group member receives the group key initiation information, selects a random number, and sends it to the previous user through a public channel; The group members receive the random number, calculate the summary value and temporary value, generate the message verification code, and send the authentication information through the public channel; The group manager receives the authentication information, calculates the group key, and broadcasts the group key negotiation information; The group members receive the group key agreement information and generate new symmetric group keys and asymmetric group keys.

[0010] Further, the symmetric encryption method includes selecting a timestamp, generating a session key, calculating a ciphertext, and sending the ciphertext data through a public channel; Furthermore, the symmetric decryption method includes receiving ciphertext data, verifying a timestamp, generating a session key, and decrypting the ciphertext data.

[0011] Furthermore, the public key encryption method includes selecting a random number, calculating the random number, selecting a timestamp, calculating a ciphertext, and sending the ciphertext data through a public channel.

[0012] Furthermore, the private key decryption method includes receiving ciphertext data, verifying a timestamp, and calculating plaintext data.

[0013] The beneficial effects of the present invention are: The present invention supports dynamic key updates when drones join or leave through symmetric group key negotiation and asymmetric group key negotiation mechanisms, thereby improving the privacy protection of drones and the traceability of malicious drones. It also has multiple security features such as anonymity, complete forward and backward security, and temporary information security of known specific sessions, which can greatly meet various security requirements of drone networks.

[0014] The present invention combines symmetric group key negotiation and asymmetric group key negotiation mechanisms to generate a symmetric group key and an asymmetric group key for the drone group, uses the symmetric group key to provide efficient and secure communication guarantees for members in the drone group, and uses the asymmetric group key to ensure the transmission security when the group members interact with external devices (such as smart phones, wearable devices, etc.). Secondly, both types of group key negotiation mechanisms support dynamic updating of group keys when drones join or leave the group, ensuring data transmission security in the highly dynamic and highly mobile environment of the drone network. More importantly, the method has a privacy protection function, which can effectively prevent data leakage, trace the behavior of malicious drones, ensure the anonymity and forward security of data interaction, and meet the high standards of drone networks for privacy and security. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of a system model of a privacy protection and dynamic certificateless group key negotiation method in a drone network of the present invention; Figure 2 A symmetric group key negotiation flow chart of the privacy protection and dynamic certificateless group key negotiation method in the drone network of the present invention; Figure 3 The present invention is a flow chart of an asymmetric group key negotiation method for privacy protection and dynamic certificateless group key negotiation in a drone network. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention but are not intended to limit the present invention.

[0017] like Figure 1-3 As shown, the present invention comprises the following steps: Generate public and private keys based on the key generation center and trusted registration agency to build a drone network cryptography system; The drone obtains a temporary pseudonym and part of the private key to generate a complete key pair; Select a group manager and complete symmetric and asymmetric group key negotiation through interaction; Generate a symmetric group key and an asymmetric group key for intra-group and extra-group communications respectively; When a drone joins or leaves the group, the group key is dynamically updated.

[0018] These include a key generation center, a trusted registration authority, and multiple group member drones. ,in, The real-world identifier of the drone device.

[0019] System initialization phase In the system initialization phase, it mainly includes the generation of public and private keys of the key generation center and the trusted registration agency, as well as the generation of system public parameters, to complete the construction of the entire drone network cryptographic system. The specific process is as follows.

[0020] Based on safety parameters , the key generation center selects an additive cyclic group , a multiplicative cyclic group and the additive cyclic group A generator of ,in, and The order of After that, the key generation center selects a bilinear pairing operation , 5 hash functions , , , , , and a message authentication code HMAC function ,in, Indicates the bit length of the drone identifier, Indicates the bit length of the symmetric key. Afterwards, the key generation center will share some system public parameters Sent to a trusted registration authority via a secure channel; After receiving some system public parameters, the trusted registration authority After that, first choose a random number As your own private key, calculate As the public key of the trusted registration authority; secondly, the trusted registration authority will Send to the key generation center via a secure channel; After receiving the public key information from the trusted registration authority, the key generation center first selects a random number As the main system key and keep it secret, calculate As the system public key; finally, the key generation center generates the system public parameters , and through public channels Send to all devices in the drone network .

[0021] User registration stage During the user registration phase, the drone Through secure interaction with the key generation center and the trusted registration authority, temporary pseudonyms and partial private key generation can be obtained to protect the privacy data of the drone, that is, the real identity. Finally, the drone generates its own complete key based on its own secret value, as follows.

[0022] Secret value generation Drones After receiving the system public parameters Then, randomly select As a secret value, calculate as part of your public key and send the pseudonym request through a secure channel Sent to a trusted registration authority.

[0023] Pseudonym Generation The trusted registration authority receives the drone Pseudonym request After that, check Whether it is in the list of legal drones. If not, the trusted registration agency directly discards it; otherwise, the trusted registration agency performs the following calculation operations.

[0024] Calculating temporary values and ,in, It's a pseudonym The effective time.

[0025] set up As a drone A temporary pseudonym to generate a partial private key request , and request the partial private key through a secure channel Send to .

[0026] Partial private key generation The key generation center receives a partial private key request After that, the following calculation process is performed to generate the drone Part of the private key.

[0027] Pick a random number ,calculate As part of the drone's public key and digest value , Represents a hash function; calculate As a drone Part of the private key, and return part of the private key Sent to the drone via a secure channel .

[0028] Complete key generation Drones After receiving the partial private key reply After that, perform the following calculation process to generate all of its own public and private key pairs.

[0029] Calculating temporary values , using the hash function , judge and verify the equation Is it true? If true, then the drone Consider pseudonym Effective, will as its temporary identity and continue with the next step; otherwise, the drone The message was considered illegal and a new pseudonym application was initiated.

[0030] With the help of hash functions calculate , judge and verify the equation Is it true? If true, the drone Set all your private keys to , all of your public keys are Otherwise, drones The private key is considered illegal and a new pseudonym is applied for.

[0031] Group key negotiation phase If there is a drone network application scenario, there is a drone group ,Include Drone equipment , when the cluster To generate a group key to ensure secure transmission of group member data, select A device with rich computing and communication resources is used as the group manager to distribute group key information to other group members (if the computing and communication resources of all group members are the same, a node can be randomly selected as the group manager). In the group key distribution method proposed in the present invention, As a drone group management node, it completes symmetric group key negotiation and asymmetric group key negotiation through interaction with other common drone devices.

[0032] Step 1: The group manager initiates a group key negotiation request Group Manager After obtaining other group members Public key information Under the premise of ,in ; Afterwards, the group manager Pick a random number As the identifier information of this group key negotiation, and the group key initiation information Send to all drones in the group by broadcasting .

[0033] Step 2: Group Members Upon receiving the group key initiation message Then, perform the following calculation.

[0034] Pick a random number , calculate random values ; According to the identity ring The order of identities in Sent to the previous drone device via an open channel ,in .

[0035] Step 3: Group Members Upon receipt Data sent Then, perform the following calculation.

[0036] Based on the previously generated random number , and the random number received , using the hash function and , calculate the summary value , and ; Calculating temporary values ; Calculating temporary values and summary value ,in, represents a hash function; With the help of message verification code function , generate a message verification code , and the authentication information }Sent to via public channel ; Step 4: Group Members Upon receipt Data sent and Authentication information sent }, perform the following calculation.

[0037] Based on the previously generated random number and , using the hash function and , calculate the summary value , , ; Calculating temporary values and ; With the help of hash functions ,calculate , and determine the verification equation Is it true? If true, it means authentication information } is valid and proceed to the next step.

[0038] Based on hash function and ,calculate and ; Calculating temporary values and ; calculate and ; With the help of message verification code function Function, generate message verification code , the authentication information }Sent to via public channel , and the group key negotiation information Transmitted to all drones in the group by broadcasting; Step 5: Group Manager Upon receiving Authentication information sent }, perform the following calculation to generate the group key: Based on hash function and , calculate the summary value , ; Calculating temporary values and ; Based on hash function And the message verification code function , calculate the summary value , and determine the verification equation Is it true? If true, it means authentication information } is valid and proceed to the next step.

[0039] calculate , and the group key negotiation information Transmitted to all member drones in the group by broadcasting .

[0040] Step 6: Symmetric group key negotiation: members of each group After receiving the group key negotiation information broadcasted by other group members Then, the following calculation process is performed to generate a symmetric key known only to users in the group to ensure the secure transmission of data within the group. The specific process is as follows: Figure 2 shown.

[0041] Based on the received multiple group key agreement information , judge and verify the equation If true, it means that the received If it is valid, proceed to the next step; otherwise, discard the message directly and re-initiate group key negotiation.

[0042] Calculate the temporary value in the following way : … judge Is it true? If so, execute the next step; otherwise, abandon it directly; Based on hash function , calculate the group symmetric key As a drone swarm The group symmetric key is used to ensure the security of data transmission among group members using a symmetric encryption algorithm.

[0043] Step 7: Asymmetric group key negotiation: members of each group After receiving the group key negotiation information broadcasted by other group members Then perform the following calculation process to generate a private key known only to group members and a public key known to all users. The specific process is as follows Figure 3 shown.

[0044] Group Members The random number generated in the first step Send to group admins ; Group Administrator After receiving the random numbers sent by all users Then, combine the generated , for each Devices based on hash functions and , calculate successively and ; Generate the group public key according to the following calculation process ; Afterwards, the group administrator The group public key information is broadcasted Spread to all drone devices.

[0045] Group Members Receive group public key information Afterwards, the temporary values ​​are calculated in sequence according to the calculation process of the symmetric group key negotiation , , …, ; after, judge Is it true? If so, execute the next step; otherwise, abandon it directly; at last, Calculate the group private key , and determine the verification equation Is it true? If true, then the group members Consider this group of asymmetric keys The public and private keys are used to asymmetrically encrypt private data.

[0046] Group key encryption and decryption phase This method can generate symmetric group keys and asymmetric group keys respectively. Therefore, group key encryption can be divided into two sub-parts: symmetric encryption and asymmetric encryption, as follows.

[0047] Group symmetric key encryption Symmetric encryption Assume that the group members Want to transfer data To other members in the group, the specific encryption and decryption process is as follows: Select a timestamp , using the hash function , generate a session key ,in, is the hash function used to generate the session key; Calculate ciphertext , and transmit the encrypted data through the public channel It is sent to other drones in the group through broadcast, where: Represents a symmetric encryption algorithm; Symmetric decryption Other group members Upon receiving the ciphertext data After that, perform the following calculation to complete the plaintext data restoration.

[0048] Get the current timestamp , judge and verify the equation Determine whether the timestamp is valid, where: Indicates the lifespan of the ciphertext. If the verification fails, the ciphertext data If the lifetime expires, discard it directly; otherwise, proceed to the next step.

[0049] With the help of hash functions ,generate and Get the plaintext data .in, Represents a symmetric decryption algorithm.

[0050] Group public key encryption Public Key Cryptography Assume there is a device outside the drone cluster Want to give drone crew members Transferring Data , the specific encryption process is as follows.

[0051] Pick a random number , calculate the random number ; Select a timestamp , calculate the ciphertext , and transmit the encrypted data through the public channel Send to drones in the group via broadcast ,in, Indicates the timestamp, Is a hash function used for encryption.

[0052] Private key decryption Drones in the group Upon receiving the ciphertext data After that, perform the following calculation to complete the plaintext data restoration.

[0053] Get the current timestamp , execute the verification equation Determine whether the timestamp is valid, where: Represents ciphertext If the verification fails, the ciphertext data lifetime has expired and is discarded directly; otherwise, proceed to the next step.

[0054] Based on hash function ,calculate Get the plaintext data .

[0055] Drone joining stage Considering the rapid mobility of drone equipment, if a drone group External drone equipment Want to join , the group key must change dynamically as the process progresses. The specific process is as follows.

[0056] Step 1: Group Administrator Announce group member joining information.

[0057] Drone Crew Manager The random number Send to device ; Drone Crew Manager Generate a new identity ring , and initiates the message by broadcasting the group key Send to drones in the group by broadcasting ; Drone equipment Upon receiving the group key initiation message After that, the group key negotiation information Send to device .

[0058] Step 2: New Team Members Upon receiving the group key initiation message Then, perform the following calculation.

[0059] Pick a random number , calculate the random number ; The random number Sent to the previous user via a public channel ; Step 3: Team members Upon receiving the random number Then, perform the following calculation.

[0060] Based on the previously generated random number , and received , using the hash function and , calculate the summary value and ; Recalculate temporary value and ; Recalculate temporary value and , represents a hash function; Based on the message authentication code function , generate a message verification code , the authentication information }Sent to via public channel , and the group key negotiation information Transmitted to all drones in the group by broadcasting; Step 4: Team members Upon receiving the authentication information }, perform the following calculation.

[0061] Based on the previously generated random number and , using the hash function and , calculate the summary value , , ; Calculating temporary values and ; Calculating temporary values , and with the help of the message verification code function , judge and verify the equation Is it true? If true, it means the authentication message Valid, and continue to the next step.

[0062] With the help of hash functions and , calculate the summary value and ; Calculating temporary values and ; Calculating temporary values and ; With the help of message verification code function , generate a message verification code , the authentication message }Sent to via public channel , and the group key negotiation information Transmitted to all drones in the group by broadcasting; Step 5: Group Manager Upon receiving Authentication message sent }, perform the following calculation to generate the group key: With the help of hash functions and , calculate the summary value , ; Recalculate temporary value and calculation ; Based on hash function And the message verification code function , calculate the summary value , and determine the verification equation Is it true? If true, it means the authentication message } is valid and proceed to the next step.

[0063] Recalculate , and the group key agreement message Transmitted to all member drones in the group by broadcasting.

[0064] Step 6: Symmetric group key negotiation: members of each group Upon receiving Broadcast group key agreement message Then the following calculation process is performed to generate a new symmetric key user-protected data transmission known only to users in the group. The specific process is as follows.

[0065] Based on the received group key agreement message , judge and verify the equation If true, it means that the received If it is valid, proceed to the next step; otherwise, discard the message directly and re-initiate group key negotiation.

[0066] Calculate the temporary value in the following way ; … judge Is it true? If so, execute the next step; otherwise, abandon it directly; Recalculate the group symmetric key It is used as the group symmetric key and uses a symmetric encryption algorithm to ensure the security of data transmission among group members.

[0067] Step 7: Asymmetric group key negotiation: members of each group Upon receiving Broadcast group key negotiation information Then the following calculation process is performed to generate a private key that is only known to group members and a public key that is known to all users. The specific process is as follows.

[0068] Group Members The random number generated in the first step Send to group admins ; Group Administrator After receiving the random numbers sent by all users Then, combine the generated ; Group Administrator For each drone device , based on hash functions and , calculate successively and ; Group Administrator After receiving the random numbers sent by all users Then, combine the random number you generate , regenerate the group public key according to the following calculation process ; Afterwards, the group administrator The group public key information is broadcasted Spread to all drone devices; Group Members Receive group public key information After that, the temporary value is calculated in the following way , , …, , ; … Afterwards, group members judge Is it true? If so, execute the next step; otherwise, abandon it directly; Finally, the group members calculate , and determine the verification equation Is it true? If true, then the group members Consider this group of asymmetric keys The public and private keys are used to asymmetrically encrypt private data.

[0069] Drone departure phase Considering the rapid mobility of drone equipment, if a group Drone equipment inside Want to leave the drone group , the group key must change dynamically as the process progresses. The specific process is as follows.

[0070] first step: Drone Crew Manager A new identity ring , and initiates the message by broadcasting the group key Send to drones in the group by broadcasting .

[0071] Step 2: Team members Upon receiving the group key initiation message Then, perform the following calculation.

[0072] The random number Sent to the previous user via a public channel ; Step 3: Team members Upon receiving the random number Then, perform the following calculation.

[0073] Based on the previously generated random number , , and received , using the hash function and ,calculate and ; Recalculate temporary value and ; Recalculate temporary value and ; With the help of message verification code function , generate a message verification code , the authentication message }Sent to via public channel , and the group key negotiation information Transmitted to all drones in the group by broadcasting; Step 4: Team members Upon receiving the authentication message }, perform the following calculation.

[0074] Based on the previously generated random number and , using the hash function and ,calculate ,and ; Recalculate temporary value and ; Based on hash function And the message verification code function , calculate the temporary value , and determine the verification equation Is it true? If true, it means the authentication message } is valid and proceed to the next step.

[0075] Recalculate , and the group key negotiation information Transmitted to all drones in the group by broadcasting; Step 5: Symmetric group key negotiation: members of each group Upon receiving Broadcast group key negotiation information Then the following calculation process is performed to generate a new symmetric key user-protected data transmission that is only known to users in the new group. The specific process is as follows.

[0076] Based on the received group key agreement information , judge and verify the equation If true, it means that the received If the message is valid, the next step is executed; otherwise, the message is discarded and group key negotiation is initiated again.

[0077] Calculate the following calculation process in sequence to calculate the temporary value : … … judge Is it true? If so, execute the next step; otherwise, abandon it directly; Based on hash function , recalculate the group symmetric key As a new group symmetric key, a symmetric encryption algorithm is used to ensure the security of data transmission among group members.

[0078] Step 7: Asymmetric group key negotiation: members of each group Upon receiving Broadcast group key negotiation information Then the following calculation process is performed to generate a private key that is only known to group members and a public key that is known to all users. The specific process is as follows.

[0079] Group Administrator After receiving the random numbers sent by all users Then, combine the generated ; Based on hash function and , calculate successively and ; Generate a new group public key according to the following calculation process : Afterwards, the group administrator The group public key information is broadcasted Spread to all drone devices.

[0080] Group Members Receive group public key information Afterwards, the temporary values ​​are calculated in sequence according to the calculation process of the symmetric group key negotiation , , …, ; Afterwards, group members judge Is it true? If so, execute the next step; otherwise, abandon it directly; Finally, the group members Calculate the group private key , and determine the verification equation Is it true? If true, then the group members Consider this group of asymmetric keys The public and private keys are used to asymmetrically encrypt private data.

[0081] In order to verify the security strength and feasibility of the solution proposed in the present invention, the present invention will discuss the security properties that the proposed solution can meet, including non-repudiation, unlinkability, anonymity, traceability, privacy protection, perfect forward and backward security, and known session-specific temporary information security.

[0082] To prevent drones Denying participation in group key negotiation, in the solution proposed by the present invention, CDH security assumption and message authentication code are used to prevent drones from denying participation in the computation process. If the group key negotiation is successful, then during the negotiation process, Based on the received ,calculate , and , and through public channels }Send to . Upon receiving }, you need to complete However, in In the calculation of , and Only legal To have, based on CDH security assumptions , other attackers cannot forge the correct and through Therefore, if If the verification is passed, it means right The legitimacy check passes, and Cannot deny that it sent the } and have participated in the key negotiation of this round.

[0083] In the group key negotiation process proposed by the present invention, based on the CDH security assumption, an attacker cannot calculate and obtain the real identity of any group member in a specific group key negotiation session. First, in the first step of the group key negotiation, the group administrator generates a ring R and sends it to all drones in the group. However, the temporary identity information of the drone is used in R. Since the private key of the trusted registration authority cannot be obtained, the attacker cannot obtain the private key of the trusted registration authority. ,Based on the CDH security assumption, the attacker cannot obtain the real identity of the drone. Secondly, for the communication between adjacent devices during the group key negotiation process, there are mainly }and In both cases, there is no explicit information to identify the drone. Therefore, the group key agreement scheme proposed in the present invention can meet the anonymity requirement.

[0084] In order to protect the privacy data of drones, the solution proposed by the present invention takes the real identity of drones as an example, and can protect the privacy of drone identities under the security assumption of the CDH problem. In order to protect the identity information of drones, a trusted registration agency is added in the solution proposed by the present invention to assign a temporary legal pseudonym to each drone. , thereby achieving security protection of the drone’s true identity. Since it is impossible to obtain the private key of a trusted registration agency, based on the CDH problem , the attacker cannot calculate the correct , thereby obtaining the drone’s private data, that is, its real identity.

[0085] In order to ensure the rapid tracing of the true identity of malicious drones during group key negotiation, in the solution proposed by the present invention, when the drone device finds an illegal drone due to verification failure, the trusted registration agency can perform The real identity of illegal drone equipment can be quickly traced, and corresponding security protection services can be provided. Therefore, the solution proposed by the present invention meets the traceability requirement.

[0086] Similar to the anonymity proof process, an attacker cannot determine whether the two group key negotiations are implemented by the same group based on the messages sent during the two group key negotiations. First, during the group key negotiation process, the drones all use pseudonyms to implement group key negotiation. Based on the CDH security assumption, the attacker cannot calculate the real identity of the drone and thus determine that the group members of the two group key negotiations belong to the same group. Secondly, for the data interaction between adjacent group members during the group key negotiation process, the attacker cannot determine }and } belong to the same group member. Therefore, the solution proposed by the present invention satisfies the unlinkability.

[0087] Assume that the long-term private keys of all group members Even if the group session key is leaked, the attacker still cannot calculate the correct group session key before or after the group key negotiation. The proof process is as follows. To calculate the correct group session key, the attacker must calculate the correct , , …, However, for any , even if it is possible to calculate , and However, since the attacker cannot obtain and , based on the CDH security assumption, an attacker cannot calculate the correct Therefore, the solution proposed by the present invention satisfies perfect forward and backward security.

[0088] Session-specific temporary information is known to be secure Similar to the proof of perfect forward and backward security, if the attacker can obtain the Random value for group key negotiation process , the attacker still cannot calculate the correct group key, as shown below. In the solution proposed by the present invention, in order to calculate the correct group key, the attacker must calculate Based on random numbers and , the attacker can successfully calculate , and However, due to All private keys or All private keys , based on the CDH security assumption, an attacker cannot calculate the correct , and then calculate the correct group session key. Therefore, the solution proposed by the present invention satisfies the security of known session-specific temporary information.

[0089] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A privacy protection and dynamic certificateless group key negotiation method in a drone network, characterized in that: include: Generate public and private keys based on the key generation center and trusted registration agency to build a drone network cryptography system; The drone obtains a temporary pseudonym and part of the private key to generate a complete key pair; Select a group manager and complete symmetric and asymmetric group key negotiation through interaction; Generate a symmetric group key and an asymmetric group key for intra-group and extra-group communications respectively; When a drone joins or leaves the group, the group key is dynamically updated.

2. A privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: The key generation center selects the additive cyclic group, the multiplicative cyclic group and the generator, selects the bilinear pairing operation and the hash function, and generates the system public and private keys; The trusted registration authority selects a private key, calculates a public key, and sends it to the key generation center through a secure channel; The key generation center generates system public parameters and sends them to all devices in the drone network through public channels.

3. The privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: When a drone user registers, the drone receives the system’s public parameters, selects a secret value, calculates a partial public key, and sends a pseudonym request to a trusted registration authority; The trusted registration authority receives the request and checks whether the drone is legal. If it is legal, it calculates the temporary value, sets a temporary pseudonym, generates a partial private key request and sends it to the key generation center. The key generation center receives the request, selects a random number, calculates a partial public key and digest value, generates a partial private key and sends it back to the drone; The drone receives a partial private key reply and verifies it through a hash function. If the verification is successful, the complete public and private key pair is generated. Otherwise, a new pseudonym is applied for.

4. The privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: During group key negotiation, the group manager initiates a group key negotiation request, generates an identity ring, selects a random number as a group key negotiation identifier, and broadcasts group key initiation information; The group member receives the group key initiation information, selects a random number, calculates the random value, and sends it to the previous drone through the public channel; The group members receive the random number, calculate the summary value and temporary value, generate the message verification code, and send the authentication information through the public channel; The group manager receives the authentication information, calculates the group key, and broadcasts the group key negotiation information; The group members receive the group key negotiation information and generate a symmetric group key and an asymmetric group key.

5. The privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: The key generation method for the drone joining includes: The group manager announces the group member joining information, generates a new identity ring, and broadcasts the group key initiation information; The new member receives the group key initiation message, selects a random number, calculates the random number, and sends it to the previous user through a public channel; The group members receive the random number, calculate the summary value and temporary value, generate the message verification code, and send the authentication information through the public channel; The group manager receives the authentication information, calculates the group key, and broadcasts the group key negotiation information; The group members receive the group key agreement information and generate new symmetric group keys and asymmetric group keys.

6. The privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: The key generation methods when the drone leaves include: The group manager generates a new identity ring and broadcasts the group key initiation information; The group member receives the group key initiation information, selects a random number, and sends it to the previous user through a public channel; The group members receive the random number, calculate the summary value and temporary value, generate the message verification code, and send the authentication information through the public channel; The group manager receives the authentication information, calculates the group key, and broadcasts the group key negotiation information; The group members receive the group key agreement information and generate new symmetric group keys and asymmetric group keys.

7. The privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: The symmetric encryption method includes selecting a timestamp, generating a session key, calculating a ciphertext, and sending the ciphertext data through a public channel.

8. The privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: The asymmetric decryption method includes receiving ciphertext data, verifying a timestamp, generating a session key, and decrypting the ciphertext data.

9. The privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: The public key encryption method includes selecting a random number, calculating the random number, selecting a timestamp, calculating a ciphertext, and sending the ciphertext data through a public channel.

10. A privacy protection and dynamic certificateless group key negotiation method in a drone network according to claim 1, characterized in that: The private key decryption method includes receiving ciphertext data, verifying timestamp, and calculating plaintext data.

Images