Unmanned aerial vehicle cluster identity authentication method based on grouping Latin party

Abstract

The invention provides an unmanned aerial vehicle cluster identity authentication method based on a grouped Latin party, and the method comprises the following steps: S1, dividing n unmanned aerial vehicles in an unmanned aerial vehicle cluster into z authentication groups, and carrying out the parameter initialization of each unmanned aerial vehicle; s2, all the authentication groups simultaneously perform identity authentication and key negotiation of # imgabs0 # rounds in the group to obtain a public intra-group temporary session key; s3, randomly selecting one unmanned aerial vehicle from each group to carry out kn = log2z rounds of inter-group authentication and negotiation to obtain a public inter-group session key; and S4, transmitting the inter-group session key in the group based on the intra-group temporary reply key to complete unmanned aerial vehicle cluster identity authentication and key negotiation. And the number of times required by large-scale node authentication is greatly reduced by using a packet Latin square design.

Description

Technical Field

[0001] The present invention relates to the technical field of drone identity authentication, and in particular to a drone cluster identity authentication method based on grouped Latin squares. Background Art

[0002] With its highly coordinated operational capabilities, drone swarm technology provides diverse and innovative solutions in all walks of life, showing great application potential. It has great value in many fields such as disaster relief, environmental monitoring, logistics distribution, farmland management and urban air traffic. This technology provides a new and feasible means to efficiently perform complex, dangerous and difficult-to-achieve tasks.

[0003] However, the rapid increase in the number of nodes has led to a significant increase in the number of authentication times. When dealing with a large number of nodes, the communication and computing overhead of the traditional point-to-point authentication mechanism increases exponentially. For example, if n nodes need to communicate with each other, the communication cost is O(n 2 ), that is, each node needs to communicate with n nodes. Especially in high-frequency, low-latency scenarios such as drone clusters and the Internet of Things, frequent identity authentication will take up valuable bandwidth and resources, reducing the overall performance of the system. In addition, many nodes, such as IoT devices, are limited by their computing power and energy and cannot withstand complex encryption algorithms, further exacerbating the high cost of authentication. In traditional identity authentication and key agreement protocols, in order to improve this problem, some researchers have optimized the communication cost to 50% based on block design and Latin square design. and O(n=log 2 n), but the communication cost can still be further optimized.

[0004] At present, most traditional authentication schemes rely on a centralized model, which not only brings bottleneck problems to the system, but also causes the risk of single point failure, seriously affecting the reliability and availability of the system. Under a centralized architecture, when the authentication server or trust center fails, the identity authentication of the entire system will be interrupted, resulting in service unavailability. In addition, traditional schemes usually use digital certificates for identity authentication. Although they have strong security guarantees, in a large-scale node environment, the generation, distribution and verification process of digital certificates will consume a lot of computing resources and bandwidth, further slowing down the authentication speed and increasing the burden on the system. This is not only particularly evident in resource-constrained devices, but may also lead to increased delays in communication between nodes, making it difficult to meet the real-time and low-energy requirements in scenarios such as the Internet of Things. Summary of the invention

[0005] The present invention proposes a drone cluster identity authentication method based on grouped Latin squares to solve the technical problem that the authentication speed of existing authentication schemes decreases sharply when the number of nodes increases sharply or the authentication server or the trust center fails.

[0006] In order to solve the above technical problems, the present invention provides a drone cluster identity authentication method based on grouped Latin squares, comprising the following steps:

[0007] Step S1: Divide the n drones in the drone cluster into z authentication groups, and initialize the parameters of each drone;

[0008] Step S2: All authentication groups are performed simultaneously within the group Rounds of identity authentication and key negotiation to obtain a common temporary session key within the group;

[0009] The jth group of drones numbered x in each round of certification Authentication information Sent to the jth group of drones numbered y Conduct certification and negotiation;

[0010] When x-(j-1)×n / z>2 r-1 When y=x-2 r-1 ; x-(j-1)×n / z≤2 r-1 When y=2 k +x-2 r-1 , r represents the number of rounds;

[0011] Step S3: Randomly select one drone from each group to perform kn=log 2 z rounds of authentication and negotiation between groups to obtain a common inter-group session key;

[0012] The drones selected by group j in each round of inter-group certification Send the authentication information to the selected drone in group Conduct certification and negotiation;

[0013] When j>2 r-1 When l = j-2 r-1 , j≤2 r-1 hour, r represents the round number;

[0014] Step S4: Based on the intra-group temporary reply key, the inter-group session key is transferred within the group to complete the drone cluster identity authentication and key negotiation.

[0015] Preferably, the parameters for parameter initialization in step S1 include:

[0016] G: base point (generator), a point on the elliptic curve;

[0017] ID i :UAV with ID i i Identity serial number;

[0018] sid: secret information of drone cluster;

[0019] p: prime number, defining the finite field GF(p);

[0020] N: order of base point;

[0021] P i : Public key generated based on elliptic curve parameters, P i =d i ·G;

[0022] d i : A private key generated based on elliptic curve parameters.

[0023] Preferably, in step S2, the method for performing identity authentication in each round group includes:

[0024] Step S211: In the first round of authentication, all drones in group j generate a temporary random number rand x , and calculate rand x ·G

[0025] Step S212: Drone Calculate temporary key temkey = P y ·d x , P y Represents the public key of drone y; use the temporary key temkey to Perform encryption operation to obtain ciphertext Calculate the message authentication code mac x =Hmac(sid,ID x ||T x ||c x );information Send to drone T x for Timestamp of the message being sent;

[0026] Step S213: After receiving the message, use the current time T when the message was received n and m2 to determine whether these two parameters satisfy the inequality T n -m2<Δt, Δt is the effective time window, m2 represents The second parameter in the , if it meets the requirement, the verification is passed, if not, the data packet is discarded and the authentication fails;

[0027] Step S214: Calculate MAC using sid x =Hmac(sid,m1||m2||m3), if MAC x If it is the same as m4, the verification passes; otherwise, the packet is discarded and the authentication fails.

[0028] Preferably, in step S2, the method for performing key negotiation within the group includes:

[0029] Step S221: Based on a stored set of public keys Found The corresponding public key P x ;

[0030] Step S222: Calculate and obtain the temporary key temkey=P x ·d y ;

[0031] Step S223: Decrypt m3 to obtain

[0032] Step S224: right according to The algorithm is updated to obtain new

[0033] Step S225: Perform After rounds of identity authentication and key negotiation, the drones in group j have the same K j ,Right now The drones in the group use tsekey=K j sid is used as a temporary session key within the group.

[0034] Preferably, in step S3, the method of performing identity authentication between each round group includes:

[0035] Step S311: Calculate the temporary key jtemkey = P y ·d x ; The temporary session key K within the jth group j Perform encryption operation to obtain ciphertext c x =enc(jtemkey, K j ); Calculate the message authentication code mac x =Hmac(sid,ID x ||T x ||cx ); Send the message M (x，y) ={ID x , T x , c x , mac x}Send to drone Where T x for Timestamp of the message being sent;

[0036] Step S312: take over Message sentM (x，y) ={m1,m2,m3,m4};

[0037] Step S313: Use the current time T at which the message was received n and m2 to determine whether these two parameters satisfy the inequality T n -m2<Δt, Δt is the valid time window. If it meets the requirement, the verification is passed. If not, the data packet is discarded and the authentication fails.

[0038] Step S314: Calculate MAC using sid x =Hmac(sid,m1||m2||m3), if MAC x If it is the same as m4, the verification passes; otherwise, the packet is discarded and the authentication fails.

[0039] Preferably, in step S3, the method for performing key negotiation between groups includes:

[0040] Step S321: Based on a stored set of public keys Find the corresponding public key P x , calculate the temporary key jtemkey = P x ·d y ;

[0041] Step S322: Decrypt m3 to obtain K j =dec(jtemkey,m3), finally K l According to K l =K j +K l The algorithm is updated to obtain the new K l .

[0042] Step S323: After kn rounds, the drones in each group have the same inter-group session key K, i.e. K j =K,

[0043] Preferably, step S4 comprises:

[0044] Step S41: The jth group participating in the authentication in step S3 Use the temporary session key tsekey within the group to encrypt the inter-group session key K to obtain the ciphertext cip j =enc(tsekey, K); calculate the message authentication code mac j =Hmac(sid,ID x ||T x ||cip j ), T x for The timestamp of sending the message; then the data is packaged into a message mes = {ID x , T x ,cip j , mac j}Send to other drones in the group;

[0045] Step S42: Other drones in the group receive the drone After sending the message mes = {me1, me2, me3, me4}, use the current time T of the received message n and me2 to determine whether these two parameters satisfy the inequality T n -me2<Δt, Δt is the valid time window. If it meets the requirement, the verification is passed. If not, the data packet is discarded and the authentication fails.

[0046] Step S43: Other drones in the group use sid to calculate MAC j =Hmac(sid, me1||me2||me3), if MAC x If the packet is the same as me4, the verification is passed; otherwise, the packet is discarded and the authentication fails.

[0047] Step S44: Other drones in the group use the temporary session key in the group to perform a decryption operation on me3 to obtain K=dec(tsekey, m3), and calculate sekey=K·sid as the cluster session key.

[0048] Preferably, the following method is used for grouping in step S1, and the drone input n is input to obtain the optimal grouping number z:

[0049] Step S11: Initialize best_z to None, indicating that the best number of groups has not yet been found;

[0050] Step S12: Initialize best_result to positive infinity to record the absolute value of the minimum number of groups;

[0051] Step S13: for each value h from 1 to n, check whether n is divisible by h;

[0052] Step S14: If it is divisible, f_prime(h,n) is calculated by the following formula:

[0053]

[0054] Step S15: If the absolute value of f_prime(h,n) is smaller than the current best_result, f_prime(h,n) is used as the new best_result to update best_result, and h is used as the new z to update z;

[0055] Step S16: Repeat steps S13 to S14, and output the final z as the number of groups.

[0056] The beneficial effects of the present invention include at least: the present invention uses the group Latin square design to greatly reduce the number of times required for large-scale node authentication. Usually, the number of communications required for n drones to authenticate and negotiate the key is O(n 2 ), based on block design and Latin square design, the communication cost is optimized to and O(n×log 2 n), and the communication cost is further reduced after the group Latin square optimization based on the present invention. 16 drones only need 48 communications, which is more than 20% lower than the block design and Latin square design. When the number of nodes reaches 521, it is reduced by nearly 80% and 50%. Moreover, as the value of n increases, the advantage of the cluster identity authentication scheme proposed in the present invention becomes greater. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 A schematic diagram of a method flow chart of an embodiment of the present invention;

[0058] Figure 2 Schematic diagram of authentication communication cost comparison according to an embodiment of the present invention. DETAILED DESCRIPTION

[0059] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention.

[0060] Example 1

[0061] like Figure 1As shown, an embodiment of the present invention provides a drone cluster identity authentication method based on grouped Latin squares, comprising the following steps:

[0062] Step S1: Divide the n drones in the drone cluster into z authentication groups, and initialize the parameters of each drone;

[0063] Step S2: All authentication groups are performed simultaneously within the group Rounds of identity authentication and key negotiation to obtain a common temporary session key within the group;

[0064] The jth group of drones numbered x in each round of certification Authentication information Sent to the drone numbered y in group h Conduct certification and negotiation;

[0065] When x-(j-1)×n / z>2 r-1 When y=x-2 r-1 ; x-(j-1)×n / z≤2 r-1 When y=2 k +x-2 r-1 , r represents the number of rounds;

[0066] Step S3: Randomly select one drone from each group to perform kn=log 2 z rounds of authentication and negotiation between groups to obtain a common inter-group session key;

[0067] The drones selected by group j in each round of inter-group certification Send the authentication information to the selected drone in group Conduct certification and negotiation;

[0068] When j>2 r-1 When l = j-2 r-1 , j≤2 r-1 hour, r represents the round number;

[0069] Step S4: Based on the temporary session key within the group, the inter-group session key is transferred within the group to complete the drone cluster identity authentication and key negotiation.

[0070] Specifically, in the initialization phase, each independent UAV completes parameter initialization with the help of the ground station / control station, and then enters the identity authentication phase, which can be divided into three sub-phases: intra-group authentication and negotiation, inter-group authentication and negotiation, and intra-group key transfer.

[0071] In this embodiment, in the initialization phase, the total number of drones in the drone cluster is recorded as n, and the number of UAVs is iFor example, i is the drone number. The ground station will determine the parameters p, G, N of the elliptic curve at this stage and generate a public key set sid and private key d i The above parameters are passed to the UAV through a secure communication channel i The specific meanings of the parameters are shown in Table 1.

[0072] Table 1: Parameters and their meanings

[0073]

[0074] In-group authentication and negotiation

[0075] In this stage, the UAV cluster needs to be divided into z groups according to the number of nodes n. For example, when the number of nodes is 8, it is divided into 4 groups. The groups need to be grouped in the order of number i, such as UAV 1 and UAVs 2 Assigned to the first group, denoted as and When the number is 32, it is divided into 16 groups, and when the number is 128, it is divided into 32 groups.

[0076] After grouping, each group has n / z drones, and all groups start identity authentication and key negotiation at the same time, which requires In each round, we take the hth group as an example. Need to Send to When x-(j-1)×n / z>2 r-1 When y=x-2 r-1 ,x-(j-1)×n / z≤2 r-1 When y=2 k +x-2 r-1 , r represents the rth round. After the kth round of authentication is completed, the public intra-group temporary session key of each group is obtained.

[0077] Inter-group authentication and negotiation

[0078] In this stage, each group randomly selects a drone for inter-group authentication and negotiation. For example, the drone selected by the jth group is recorded as The drone selected in group l is denoted as kn=log is required between drones 2 z rounds of authentication and negotiation, each round of drone The message M needs to be (x，y) Send to When j>2 r-1 When l = j-2 r-1 , j≤2 r-1 hour, r represents the rth round. After completing kn rounds of authentication, a common inter-group session key is obtained.

[0079] Intra-group key delivery

[0080] In this step, for example, the jth group is connected to the drone through authentication and negotiation between the groups. Explanation: Drone The inter-group session key is encrypted and decrypted by the intra-group temporary session key and then passed to other drones in the jth group. After each group completes the key transfer, each drone in the drone cluster obtains the same negotiated key, thus completing the drone cluster identity authentication and key negotiation.

[0081] By adopting the scheme of this embodiment, the design of group Latin square effectively reduces the communication cost. In the traditional scheme, the number of communications required for n drones to authenticate and negotiate the key is usually O(n 2 ), based on block design and Latin square design, the communication cost is optimized to and O(n×log 2 n), and the communication cost of the solution of this embodiment is further reduced after the group Latin square optimization, as shown in Table 2 and Figure 2 As shown, Figure 2 The corresponding comparison method in is The corresponding comparison method is O(n=log 2 n), only 48 communications are required for 16 drones, which is more than 20% lower than the other two methods. When the number of nodes reaches 521, it is reduced by nearly 80% and 50%. As the value of n increases, the effectiveness of the cluster identity authentication scheme proposed in the embodiment of the present invention is proved.

[0082] Table 2

[0083]

[0084] Example 2

[0085] In order to further reduce the computing overhead, this embodiment improves the authentication process of the three sub-stages of intra-group authentication and negotiation, inter-group authentication and negotiation, and intra-group key transfer based on Embodiment 1. Instead of adopting the traditional authentication method, the identity authentication of the cluster nodes is completed by using pre-shared secret information, message authentication code HMAC algorithm, symmetric encryption and other algorithms instead of digital certificates.

[0086] Specifically, the following steps are used to perform intra-group authentication and negotiation.

[0087] Step 1: In the first round of authentication, each drone generates a temporary random number. For example, generate a random number rnadx Post-calculation rnad x ·G After the first round, the updated Proceed to next steps.

[0088] Then calculate the temporary key temkey = P y ·d x , using this key to pair data Perform encryption operation to obtain ciphertext Calculate the message authentication code mac x =Hmac(sid,Id x ||T x ||c x ), then the message Where T x for Timestamp of the message sent, sent to the drone

[0089] Step 2, take over Messages sent Use the current time T at which the message was received n and m2 to determine whether these two parameters satisfy the inequality T n -m2<Δt, Δt is the valid time window. If it is satisfied, the verification is passed. If it is not satisfied, it may be subject to replay attack and the data packet will be discarded.

[0090] Step 3: Calculate MAC using sid x =Hmac(sid,m1||m2||m3), if MAC x If it is the same as m4, it passes the verification; otherwise, the data packet may be tampered with and will be discarded.

[0091] Step 4: Based on a stored set of public keys Find the corresponding public key P x , calculate the temporary key temkey = P x ·d y According to the associative and commutative laws of elliptic curve scalar multiplication, P x ·d y =P y ·d x , so this step The obtained temkey is the same as the temkey obtained in step 1. Then m3 is decrypted and obtained at last right according to The algorithm is updated to obtain new

[0092] After k rounds, the drones in the group have the same K j ,Right now Each group of drones uses teskey=K j sid is used as a temporary session key within the group.

[0093] Perform inter-group authentication and negotiation through the following steps.

[0094] Step 1, Calculate the temporary key jtemkey = P y ·d x , using this key to the data K j Perform encryption operation to obtain ciphertext c x =enc(jtemkey, K j ), calculate the message authentication code mac x =Hmac(sid,ID x ‖T x ‖c x ), then the message M (x，y) ={ID x , T x , c x , mac x}, where T x for Timestamp of the message sent, sent to the drone

[0095] Step 2, take over Message sentM (x，y) ={m1, m2, m3, m4}. Use the current time T at which the message was received n and m2 to determine whether these two parameters satisfy the inequality T n -m2<Δt, Δt is the valid time window. If it is satisfied, the verification is passed. If it is not satisfied, it may be subject to replay attack and the data packet will be discarded.

[0096] Step 3: Calculate MAC using sid x =Hmax(sid,m1||m2||m3), if MAC x If it is the same as m4, it passes the verification; otherwise, the data packet may be tampered with and will be discarded.

[0097] Step 4: Based on a stored set of public keys Find the corresponding public key P x , calculate the temporary key jtemkey = P x ·d y , then decrypt m3 to get K x =dec(jtemkey,m3), finally K l According to K l =K j +K l The algorithm is updated to obtain the new K l .

[0098] After kn rounds, the drones in each group have the same K, that is, K j =K, Each drone uses sekey=K·sid as the session key.

[0099] Perform the following steps to perform intra-group authentication and negotiation.

[0100] Step 1: Group j participates in the authentication Use the temporary session key tsekey within the group to encrypt the inter-group session key K to obtain the ciphertext cip j =enc(tsekey, K); calculate the message authentication code mac j =Hmac(sid,ID x ||T x ||cip j ), T x for The timestamp of sending the message; then the data is packaged into a message mes = {ID x , T x ,cip j , mac j}Send to other drones in the group.

[0101] Step 2: Other drones in the group receive the drone After sending the message mes = {me1, me2, me3, me4}, use the current time T of the received message n and me2 to determine whether these two parameters satisfy the inequality T n -me2<Δt, Δt is the valid time window. If it is satisfied, the verification is passed. If it is not satisfied, it may be subject to replay attack and the data packet will be discarded.

[0102] Step 3: Other drones in the group use sid to calculate MAC j =Hmac(sid, me1||me2||me3), if MAC xIf it is the same as me4, it passes the verification; otherwise, the data packet may be tampered with and will be discarded.

[0103] Step 4: Other drones in the group use the temporary session key in the group to decrypt me3 and obtain K=dec(tsekey,m3), and calculate sekey=K·sid as the cluster session key.

[0104] Compared with the widely used identity authentication key negotiation methods such as DTLS and TLS, this embodiment completes the identity authentication of cluster nodes by using pre-shared secret information, message authentication code HMAC algorithm, symmetric encryption and other algorithms instead of digital certificates. The algorithms used, such as elliptic curve point addition, point multiplication, message authentication code HMAC, etc., have extremely low computational overhead, reducing the total computational overhead of the identity authentication key negotiation method.

[0105] Example 3

[0106] This embodiment provides a grouping method based on the first embodiment, wherein a drone input n is input to obtain an optimal grouping number z, and the method includes:

[0107] Step 1: Initialize best_z to None, indicating that the best number of groups has not yet been found;

[0108] Step 2: Initialize best_result to positive infinity to record the absolute value of the minimum number of groups;

[0109] Step 3: For each value h from 1 to n, check whether n is divisible by h;

[0110] Step 4: If it is divisible, calculate f_prime(h,n) using the following formula:

[0111]

[0112] Step 5: If the absolute value of f_prime(h,n) is smaller than the current best_result, f_prime(h,n) is used as the new best_result to update best_result, and h is used as the new z to update z;

[0113] Step 6: Repeat steps S13 to S14, and output the final z as the number of groups.

[0114] The method design of this embodiment also has extremely high scalability. In addition to being applicable to drone clusters, it can also meet the needs of other lightweight Internet of Things (IoT) devices and group data security protection in cloud computing. The protocol architecture is flexible and easy to integrate into different types of lightweight terminals, and parameters can be adjusted according to specific application scenarios to adapt to different performance requirements. Especially in resource-constrained large-scale node security protection environments, such as industrial Internet of Things, smart city infrastructure, large-scale agricultural monitoring systems, etc., this method can not only provide efficient identity authentication and key negotiation, but also ensure high security and low communication overhead. Therefore, the application of this protocol in the Internet of Things has extremely strong adaptability and broad application prospects.

[0115] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. Only the preferred embodiments of the present invention are expressed. The description is more specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. As long as there is no contradiction in the combination of these technical features, they should be considered as the scope recorded in this specification.

[0116] It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these modifications and improvements all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A drone cluster identity authentication method based on grouped Latin squares, characterized by: The following steps are involved: Step S1: Divide the n drones in the drone cluster into z authentication groups, and initialize the parameters of each drone; Step S2: All authentication groups are performed simultaneously within the group Rounds of identity authentication and key negotiation to obtain a common temporary session key within the group; The jth group of drones numbered x in each round of certification Authentication information Sent to the jth group of drones numbered y Conduct certification and negotiation; When x-(j-1)×n / z>2 r-1 When y=x-2 r-1 ; x-(j-1)×n / z≤2 r-1 When y=2 k +x-2 r-1 , r represents the number of rounds; Step S3: Each group randomly selects a drone to perform kn=log2z rounds of inter-group authentication and negotiation to obtain a common inter-group session key; The drones selected by group j in each round of inter-group certification Send the authentication information to the drone selected in group l Conduct certification and negotiation; When j>2 r-1 When l = j-2 r-1 , j≤2 r-1 hour, r represents the round number; Step S4: Based on the intra-group temporary reply key, the inter-group session key is transferred within the group to complete the drone cluster identity authentication and key negotiation.

2. According to claim 1, a drone cluster identity authentication method based on grouped Latin squares is characterized by: The parameters initialized in step S1 include: G: base point (generator), a point on the elliptic curve; ID i :UAV with ID i i Identity serial number; sid: secret information of drone cluster; p: prime number, defining the finite field GF(p); N: order of base point; P i : Public key generated based on elliptic curve parameters, P i =d i ·G; d i : A private key generated based on elliptic curve parameters.

3. The drone cluster identity authentication method based on grouped Latin square according to claim 2 is characterized by: In step S2, the method of performing identity authentication in each round group includes: Step S211: In the first round of authentication, all drones in group j generate a temporary random number rand x , and calculate rand x ·G Step S212: Drone Calculate temporary key temkey = P y ·d x , P y Represents the public key of drone y; use the temporary key temkey to Perform encryption operation to obtain ciphertext Calculate the message authentication code mac x =Hmac(sid,ID x ||T x ||c x );information Send to drone T x for Timestamp of the message being sent; Step S213: After receiving the message, use the current time T when the message was received n and m2 to determine whether these two parameters satisfy the inequality T n -m2<Δt, Δt is the effective time window, m2 represents The second parameter in the , if it meets the requirement, the verification is passed, if not, the data packet is discarded and the authentication fails; Step S214: Calculate MAC using sid x =Hmac(sid,m1||m2||m3), if MAC x If it is the same as m4, the verification passes; otherwise, the packet is discarded and the authentication fails.

4. The drone cluster identity authentication method based on grouped Latin squares according to claim 3 is characterized by: In step S2, the method for performing key negotiation within the group includes: Step S221: Based on a stored set of public keys Found The corresponding public key P x ; Step S222: Calculate and obtain the temporary key temkey=P x ·d y ; Step S223: Decrypt m3 to obtain Step S224: right according to The algorithm is updated to obtain new Step S225: Perform After rounds of identity authentication and key negotiation, the drones in the jth group have the same Kj, i.e. The UAVs in group j use tsekey=K j sid is used as a temporary session key within the group.

5. The drone cluster identity authentication method based on grouped Latin square according to claim 2 is characterized by: In step S3, the method of performing identity authentication between each round of groups includes: Step S311: Calculate the temporary key jtemkey = P y ·d x ; The temporary session key K within the jth group j Perform encryption operation to obtain ciphertext c x =enc(jtemkey,K j ); Calculate the message authentication code mac x =Hmac(sid,ID x ||T x ||c x ); Send the message M (x，y) ={ID x , T x , c x , mac x }Send to drone Where T x for Timestamp of the message being sent; Step S312: take over Message sentM (x，y) ={m1,m2,m3,m4}; Step S313: Use the current time T at which the message was received n and m2 to determine whether these two parameters satisfy the inequality T n -m2<Δt, Δt is the valid time window. If it meets the requirement, the verification is passed. If not, the data packet is discarded and the authentication fails. Step S314: Calculate MAC using sid x =Hmac(sid,m1||m2||m3), if MAC x If it is the same as m4, the verification passes; otherwise, the packet is discarded and the authentication fails.

6. The drone cluster identity authentication method based on grouped Latin squares according to claim 5 is characterized by: In step S3, the method for performing key negotiation between groups includes: Step S321: Based on a stored set of public keys Find the corresponding public key P x , calculate the temporary key jtemkey = P x ·d y ; Step S322: Decrypt m3 to obtain K j =dec(jtemkey,m3), finally K l According to K l =K j +K l The algorithm is updated to obtain the new K l ; Step S323: After kn rounds, the drones in each group have the same inter-group session key K, i.e.

7. The drone cluster identity authentication method based on grouped Latin square according to claim 2 is characterized by: Step S4 include: Step S41: The jth group participating in the authentication in step S3 Use the temporary session key tsekey within the group to encrypt the inter-group session key K to obtain the ciphertext cip j =enc(tsekey, K); calculate the message authentication code mac j =Hmac(sid,ID x ||T x ||cip j ), T x for The timestamp of sending the message; then the data is packaged into a message mes = {ID x , T x ,cip j , mac j }Send to other drones in the group; Step S42: Other drones in the group receive the drone After sending the message mes = {me1, me2, me3, me4}, use the current time T of the received message n and me2 to determine whether these two parameters satisfy the inequality T n -me2<Δt, Δt is the valid time window. If it meets the requirement, the verification is passed. If not, the data packet is discarded and the authentication fails. Step S43: Other drones in the group use sid to calculate MAC j =Hmac(sid,me1||me2||me3), if MAC x If the packet is the same as me4, it passes the verification. Otherwise, the packet is discarded and the authentication fails. Step S44: Other drones in the group use the temporary session key in the group to perform a decryption operation on me3 to obtain K=dec(tsekey,m3), and calculate sekey=K·sid as the cluster session key.

8. The drone cluster identity authentication method based on grouped Latin squares according to claim 1 is characterized by: In step S1, the following method is used for grouping. The drone input n is input to obtain the optimal grouping number z: Step S11: Initialize best_z to None, indicating that the best number of groups has not yet been found; Step S12: Initialize best_result to positive infinity to record the absolute value of the minimum number of groups; Step S13: for each value h from 1 to n, check whether n is divisible by h; Step S14: If it is divisible, f_prime(h, n) is calculated by the following formula: Step S15: If the absolute value of f_prime(h, n) is smaller than the current best_result, f_prime(h, n) is used as the new best_result to update best_result, and h is used as the new z to update z; Step S16: Repeat steps S13 to S14, and output the final z as the number of groups.

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