Authentication method, authentication system and communication method

Abstract

The invention discloses an authentication method, an authentication system and a communication method, a complex three-level architecture under a PKI (Public Key Infrastructure) framework is abandoned, a two-layer architecture of a main controller and nodes is adopted, hierarchical interaction overhead is reduced, a certificate signature request is firstly sent through the nodes, a trust chain between the two layers is established by adopting a signature verification mode, and a certificate signature request is sent through the nodes. And then, within a preset time, based on encryption, decryption, signature and signature verification of the secret key, strict identity authentication of a request-response-confirmation mechanism is completed, so that the security of data interaction during communication can be ensured.

Description

TECHNICAL FIELD

[0001] The application relates to an authentication method, an authentication system and a communication method, and belongs to the technical field of communication security. BACKGROUND

[0002] With the deep popularization of the Internet of Vehicles technology of engineering machinery, there is massive data interaction between internal components, a vehicle main controller and a cloud and an external environment. If there is no strict authentication (such as link authentication and identity authentication) before data interaction, the communication process is vulnerable to eavesdropping, tampering and replay attacks. Therefore, a strict authentication method is currently established to realize secure communication. However, there is no corresponding method at present. SUMMARY

[0003] The application provides an authentication method, an authentication system and a communication method, which solve the problems disclosed in the background art.

[0004] According to one aspect of the application, an authentication method is provided, which is implemented in a main controller integrated with a root authentication agency, and the method comprises the following steps: In response to receiving a certificate signature request signed by a node private key, a node public key is extracted from the certificate signature request, a node L sending the certificate signature request is determined according to the node public key, and signature verification is performed on the certificate signature request. If the signature verification is passed, the node entity certificate signed by the root authentication agency private key is sent to the node L in a frame transmission mode; wherein the node L stores the node entity certificate; In response to reaching a first preset time, the first identity authentication request signed by the root authentication agency private key is encrypted by using the node L public key, and the encrypted first identity authentication request is sent to the node L; wherein the first preset time is the time after the node entity certificate is stored; In response to receiving the first identity authentication request response signed by the node L private key and encrypted by using the root authentication agency public key, the first identity authentication request response is decrypted by using the root authentication agency private key, and the decrypted first identity authentication request response is verified by using the node L public key. If the signature verification is passed, the authentication is fed back to the node L.

[0005] Further, a self-signed certificate signed by the root authentication agency private key is pre-stored in the node, and the self-signed certificate comprises a main controller MCU serial number, a root authentication agency public key, a root authentication agency signature algorithm and a self-signed certificate validity period; The certificate signature request comprises a node MCU serial number and a node public key; The node entity certificate comprises a node MCU serial number, a node public key and a node entity certificate validity period; The first identity authentication request comprises a node entity certificate hash value and a first random number generated by the main controller; The first identity authentication request response includes a second random number generated by the node, the first random number, and a node MCU serial number.

[0006] Further, the method further comprises: In response to reaching a second preset time, sending a second identity authentication request encrypted by an initial pre-shared key to the cloud; wherein the initial pre-shared key is a new pre-shared key generated when the last authentication is passed; In response to receiving a second identity authentication request response encrypted by the initial pre-shared key and fed back by the cloud, decrypting the second identity authentication request response by the initial pre-shared key, and if the decrypted second identity authentication request response passes the correctness verification, generating a new pre-shared key and sending a third identity authentication request encrypted by the new pre-shared key to the cloud; In response to receiving a feedback that the third identity authentication request passes the correctness verification and fed back by the cloud, confirming that the authentication is passed.

[0007] Further, the second identity authentication request includes a main controller MCU serial number, a third random number generated by the main controller, and a first timestamp; The second identity authentication request response includes a cloud ID, a third random number generated by the main controller, a fourth random number generated by the cloud, and a second timestamp; The third identity authentication request includes a cloud ID, a fourth random number generated by the cloud, a new pre-shared key, and a third timestamp.

[0008] According to another aspect of the present application, an authentication system is provided, which is loaded in a main controller integrated with a root authentication agency, and the system comprises: A trust chain establishment module, in response to receiving a certificate signature request signed by a node private key, extracting a node public key from the certificate signature request, determining a node L sending the certificate signature request according to the node public key, and performing signature verification on the certificate signature request, if the signature verification is passed, sending a node entity certificate signed by a root authentication agency private key to the node L in a frame transmission mode; wherein the node L stores the node entity certificate; A first identity authentication request module, in response to reaching a first preset time, encrypting a first identity authentication request signed by a root authentication agency private key by a node L public key, and sending the encrypted first identity authentication request to the node L; wherein the first preset time is a time after the node entity certificate is stored; A first identity authentication module, in response to receiving a first identity authentication request response signed by a node L private key and encrypted by a root authentication agency public key, decrypting the first identity authentication request response by the root authentication agency private key, and performing signature verification on the decrypted first identity authentication request response by the node L public key, if the signature verification is passed, feeding back to the node L that the authentication is passed.

[0009] According to another aspect of the present application, there is provided an authentication method, the method is implemented in a node, wherein the node is a node connected with a master controller through a bus; the method comprises: sending a certificate signature request signed by a private key of the node to the master controller in a frame transmission mode; in response to receiving a node entity certificate signed by a root certification authority private key sent by the master controller, verifying the node entity certificate by using a root certification authority public key, and if the verification is passed, storing the node entity certificate; in response to receiving an encrypted first identity authentication request sent by the master controller, decrypting the first identity authentication request by using a private key of the node, verifying the decrypted first identity authentication request by using a root certification authority public key, and confirming the legality of the master controller according to the content in the first identity authentication request, if the verification is passed and the master controller is legal, sending a first identity authentication request response signed by the private key of the node and encrypted by the root certification authority public key to the master controller; wherein the first identity authentication request is a first identity authentication request signed by a root certification authority private key, and the encryption is performed by using a node public key of the node receiving the first identity authentication request; receiving an authentication result fed back by the master controller according to the first identity authentication request response.

[0010] Further, the node pre-stores a self-signed certificate signed by a root certification authority private key, the self-signed certificate comprising a master controller MCU serial number, a root certification authority public key, a root certification authority signature algorithm and a self-signed certificate validity period; the certificate signature request comprises a node MCU serial number and a node public key; the node entity certificate comprises a node MCU serial number, a node public key and a node entity certificate validity period; the first identity authentication request comprises a node entity certificate hash value and a first random number generated by the master controller; the first identity authentication request response comprises a second random number generated by the node, the first random number and a node MCU serial number.

[0011] Further, the method further comprises: in response to reaching a third preset time, receiving a node entity certificate of a node M; wherein the third preset time is a time after the node entity certificate is stored, a first parameter E1 is calculated according to the content of the node entity certificate of the node M and the root certification authority public key, a second parameter E2 is calculated according to the root certification authority public key, and if E1 is consistent with E2, the node M is fed back an authentication pass; wherein the node M is a node having a communication link with the node.

[0012] According to another aspect of the present application, there is provided an authentication system, which is loaded in a node, wherein the node is a node connected with a master controller through a bus; the system comprises: a certificate signature request module, which sends a certificate signature request signed by a private key of the node to the master controller in a frame transmission mode; a node entity certificate verification module, which, in response to receiving a node entity certificate signed by a root certification authority private key sent by the master controller, verifies the signature of the node entity certificate by using a root certification authority public key, and stores the node entity certificate if the signature verification is passed; a first identity authentication request response module, which, in response to receiving an encrypted first identity authentication request sent by the master controller at a first preset time, decrypts the first identity authentication request by using a private key of the node, verifies the signature of the decrypted first identity authentication request by using the root certification authority public key, and confirms the legality of the master controller according to the content in the first identity authentication request, and sends a first identity authentication request response signed by the private key of the node and encrypted by the root certification authority public key to the master controller if the signature verification is passed and the master controller is legal; wherein the first preset time is a time after the node entity certificate is stored; the first identity authentication request is a first identity authentication request signed by the root certification authority private key, and is encrypted by using a node public key receiving the first identity authentication request; an authentication result receiving module, which receives an authentication result fed back by the master controller according to the first identity authentication request response.

[0013] According to another aspect of the present application, there is provided a communication method, in which the master controller side and the node side both complete at least one authentication before encrypted communication; wherein the master controller side performs authentication by using an authentication method implemented in a master controller integrated with a root certification authority, and the node side performs authentication by using an authentication method implemented in a node; if the master controller and the node perform encrypted communication, a random number in a first identity authentication request and a random number in a first identity authentication request response are spliced to form a key for encrypted communication; if the node and the node perform encrypted communication, a temporary key obtained based on the node entity certificates of both sides is used as a key for encrypted communication.

[0014] The present application has the following beneficial effects: the present application discards the complex three-level architecture under the PKI framework, adopts a two-layer architecture of the master controller and the node, reduces the hierarchical interaction overhead, and first sends a certificate signature request by the node, establishes a trust chain between the two layers by using signature verification, and then completes strict identity authentication of the "request-response-confirmation" mechanism based on encryption, decryption, signature and verification of the key at a preset time, so as to guarantee the security of data interaction during communication. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a schematic diagram of the authentication method; Figure 2 is a block diagram of an authentication system; Figure 3 is an architecture diagram of the hardware corresponding to the authentication system. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. The following description of at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present application.

[0017] Unless otherwise specified, the relative arrangement, numerical expressions and values of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0018] It should be understood that the sizes of the various parts shown in the drawings are not drawn in accordance with the actual proportional relationship for the convenience of description.

[0019] The technologies, methods and devices known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered as part of the specification when appropriate.

[0020] In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments can have different values.

[0021] It should be noted that similar symbols and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it need not be discussed further in subsequent drawings.

[0022] Meanwhile, in the description of the embodiments of the present application, the terms "first", "second", and the like are used only to distinguish the description, and cannot be understood as indicating or implying relative importance. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features.

[0023] The application embodiments provide an authentication method, see Figure 1 ( Figure 1The authentication method mainly includes a master controller side method and a node side method. The master controller is a vehicle-mounted master controller of the engineering machinery vehicle, and internally integrates a root certificate authority (CA) for issuing certificates for the nodes. Before leaving the factory, the manufacturer writes a self-signed certificate signed by a root certificate authority (root CA) private key into a secure storage area of the node through a hardware programming tool (such as JTAG), as a "trust root" for verifying the certificate of the node.

[0024] It should be noted that the content in the self-signed certificate can mainly include the master controller MCU serial number, the root certificate authority public key, the root certificate authority signature algorithm and the self-signed certificate validity period. The self-signed certificate format can be simplified based on the X.509 standard as shown in Table 1.

[0025] Table 1: Self-signed certificate format example

[0026] The master controller side method can include: A1) In response to receiving a certificate signing request signed by a node private key, extracting a node public key from the certificate signing request, determining a node L sending the certificate signing request according to the node public key, and performing signature verification on the certificate signing request. If the signature verification is passed, the root certificate authority private key signed node entity certificate is sent to the node L in a frame transmission mode; wherein the node L stores the node entity certificate.

[0027] It should be noted that the step A1 is mainly implemented in the vehicle offline detection stage before the vehicle is offline. The nodes having a link with the master controller will generate a key pair through a built-in encryption algorithm. The node private key is stored in the node secure storage area and is not transmitted externally. The node public key is attached to the node unique device serial number, and the certificate signing request (CSR) is sent to the master controller after being signed by the node private key. The content of the certificate signing request mainly includes the node MCU serial number and the node public key, which can be referred to Table 2.

[0028] Table 2: Certificate signing request format example

[0029] In some embodiments, since the certificate signing request exceeds the 8-byte data length of the CAN standard frame, it needs to be transmitted in frames according to the rules. The transmission example is shown in Table 3. The frame sequence number is composed of the certificate signing request message sequence number and the total message number. The check value is used for fast detection of transmission errors. If the single frame data check is not passed, the single frame is immediately retransmitted.

[0030] Table 3 Certificate Signing Request Transmission Example

[0031] Since the current engineering machinery vehicle communication mode is still dominated by CAN bus, the transmission data efficiency is limited, by simplifying the transmission field, and giving the frame transmission mechanism, each frame is attached with 1 byte of check data, the receiver can quickly find the error and request retransmission of single frame, rather than full retransmission, and a lighter encryption algorithm can be recommended to further reduce the delay.

[0032] It should be noted that after the host controller receives the CSR, it will use the node public key to confirm the identity of the CSR sender, define the sending node as node L, and issue a node entity certificate for node L after the signature verification is passed; in order to facilitate transmission, the contents of the node entity certificate can include the node MCU serial number, the node public key and the node entity certificate validity period, which can be simplified based on the X.509 standard as shown in Table 4.

[0033] Table 4 Node Entity Certificate Format Example

[0034] Similar to the transmission of the certificate signing request, the host controller also uses a frame transmission method to transmit the node entity certificate, that is, it is transmitted to the node according to the rules in Table 3, and the node L uses the pre-burned root CA public key to verify the signature and store it in the secure storage area after confirming the legality, completing the trust chain establishment between the host controller and the node L. If the host controller and the node L both integrate the UDS protocol stack, the efficient issuance of the certificate can be completed based on UDS.

[0035] A2) In response to reaching the first preset time, encrypt the first identity authentication request signed by the root certification authority private key using the node L public key, and send the encrypted first identity authentication request to the node L; wherein the first preset time is the time after the node entity certificate is stored.

[0036] It should be noted that the first preset time is a time artificially specified according to requirements, which can be a time during the normal operation of the engineering machinery vehicle, such as a periodic time during the normal operation or an idle time determined according to the working condition.

[0037] When the first preset time is reached, the host controller will send the encrypted and signed first identity authentication request to the node L, and the first identity authentication request also uses a frame transmission method, and the contents of the first identity authentication request mainly include the node entity certificate hash value and the first random number generated by the host controller, and the specific data format is shown in Table 5.

[0038] Table 5 First Identity Authentication Request Format Example

[0039] The node L receives the first identity authentication request and decrypts it with its own private key, verifies the request with the root CA public key, reads the certificate from the trusted memory area and calculates the hash value to confirm that the request initiator is a legal master controller, and sends the first identity authentication request response signed by its own private key encrypted with the root certification authority public key to the master controller; wherein the first identity authentication request response mainly includes nonce2, nonce1 and node MCU serial number, nonce2 is a 4-byte second random number generated by the node L.

[0040] A3) In response to receiving the first identity authentication request response signed by the node L private key encrypted with the root certification authority public key, decrypt the first identity authentication request response with the root certification authority private key, and verify the signature of the decrypted first identity authentication request response with the node L public key, if the signature verification is passed, feedback to the node L that the authentication is passed.

[0041] It should be noted that since the node (CAN network node) is powered on or the node communication address conflict occurs after the J1939 address arbitration is triggered, the vehicle node actively or according to the command modifies its source address SA, that is, the CAN-ID will be changed, therefore, in the above method, the MCU unique device serial number is introduced as a core field in the certificate, and any data interaction can be traced back to an absolutely determined and unique vehicle node, without relying on the changed secondary information.

[0042] The node side method and the above master controller side method correspond, and can include the following steps: B1) Send its own private key signed certificate signature request (i.e. the certificate signature request shown in Table 2) to the master controller in a frame transmission manner.

[0043] B2) In response to receiving the node entity certificate signed by the root certification authority private key sent by the master controller (i.e. the node entity certificate shown in Table 4), verify the signature of the node entity certificate with the root certification authority public key, if the signature verification is passed, store the node entity certificate.

[0044] B3) In response to receiving the encrypted first identity authentication request sent by the master controller (i.e., the first identity authentication request shown in Table 5), the first identity authentication request is decrypted using the private key of the node itself, the decrypted first identity authentication request is verified by signature using the root authentication agency public key, and the legality of the master controller is confirmed according to the content in the first identity authentication request. If the signature verification is passed and the master controller is legal, the first identity authentication request response signed by the private key of the node itself encrypted by the root authentication agency public key is sent to the master controller (i.e., { nonce1, nonce2, node MCU serial number}). Wherein, the first identity authentication request is the first identity authentication request signed by the root authentication agency private key, and the encryption uses the public key of the node receiving the first identity authentication request.

[0045] B4) Receiving the authentication result fed back by the master controller according to the first identity authentication request response.

[0046] It should be noted that since the master controller is the ultimate anchor point for identity authentication of vehicle parts, there is a risk of single point failure, so in some embodiments, a master controller authentication process will be added to the master controller side method, which can specifically include: C1) In response to reaching the second preset time, a second identity authentication request encrypted by the initial pre-shared key is sent to the cloud; wherein the initial pre-shared key is a new pre-shared key generated when the last authentication is passed.

[0047] It should be noted that the second preset time here is also a time artificially specified according to demand, which can be a time in the normal running stage of the construction machinery vehicle, or a time in the detection stage before the vehicle is offline. This time can be a periodic time, or an idle time determined according to the working condition.

[0048] When the second preset time is reached, the master controller sends a second identity authentication request to the cloud through TBOX via Ethernet or CAN, the content of the second identity authentication request can mainly include the master controller MCU serial number, the third random number (defined as nonce3) generated by the master controller, and the first timestamp, denoted as {master controller MCU serial number, nonce3, first timestamp}, and transmitted using the initial pre-shared key (denoted as PSK).

[0049] The cloud has a list of master controller MCU serial numbers, and after receiving the second identity authentication request, the validity of the timestamp (such as within ±30 seconds) and the master controller MCU serial number is verified, a second identity authentication request response is generated, and is encrypted and sent to the master controller; wherein the content of the second identity authentication request response can mainly include the cloud ID, nonce3, the fourth random number (defined as nonce4) generated by the cloud, and the second timestamp, denoted as {cloud ID, nonce3, nonce4, second timestamp}.

[0050] C2) in response to receiving the cloud feedback of the second identity authentication request response encrypted with the initial pre-shared key, decrypting the second identity authentication request response with the initial pre-shared key, if the decrypted second identity authentication request response passes the correctness verification, generating a new pre-shared key, and sending a third identity authentication request encrypted with the new pre-shared key to the cloud.

[0051] The main controller decrypts the second identity authentication request response and verifies the correctness of the reply, calculates a new pre-shared key based on the PSK, nonce3 and nonce4, denoted as PSK_new, and the formula can be: PSK_new=Hash(PSK||nonce3||nonce4); In the formula, Hash is a Hash function, and || represents the connection of multiple data, but is not simply spliced directly, and unique separators or other measures can be used for multi-data connection.

[0052] The third identity authentication request is encrypted with PSK_new, and the encrypted third identity authentication request is sent to the cloud; wherein the content of the third identity authentication request can mainly include cloud ID, nonce4, PSK_new and third timestamp, denoted as {cloud ID, nonce4, PSK_new, third timestamp}.

[0053] The cloud receives the third identity authentication request and verifies it, if the verification is successful, the cloud discards PSK and receives PSK_new as a new shared key, and feeds back the result to the main controller. If the verification fails, the cloud immediately issues an alarm and starts a response mechanism.

[0054] C3) in response to receiving the cloud feedback of the third identity authentication request correctness verification, it is confirmed that the authentication is passed; wherein the main controller also discards PSK and receives PSK_new as a new shared key after the authentication is passed.

[0055] By constructing the main controller-cloud authentication link, the safety communication link closed loop of the whole vehicle can be realized, and the risk of single point failure can be avoided.

[0056] It should be noted that in addition to the communication between the main controller and the nodes, there will also be communication between the nodes, for example, the node L engine controller needs to communicate with the node M range extender controller, therefore, in some embodiments, the process of node authentication will be added to the node side method, and the specific process can be as follows: In response to reaching the third preset time, the node entity certificate of the receiving node M is received, a first parameter E1 is calculated according to the content of the node entity certificate of the node M and the root certification authority public key (E1 and E2 are two points on an elliptic curve calculated based on the characteristics of the Ed25519 algorithm), a second parameter E2 is calculated according to the root certification authority public key, and if E1 is consistent with E2, the node M is fed back that the authentication is passed; wherein the node M is a node that has a communication link with itself, and the third preset time is a time after the node entity certificate is stored.

[0057] It should be noted that the third preset time here is the same as the first preset time described above, which is not repeated here. When the third preset time is reached, the nodes exchange their respective node entity certificates.

[0058] The node L extracts the core field C (i.e. the node MCU serial number, the node public key and the validity period) and the root CA signature S of the Ed25519 algorithm from the node entity certificate of the node M, inputs C, S and the pre-stored root CA public key P to the Ed25519 algorithm, and the algorithm calculates a point E1 on the elliptic curve according to C, S, and another point E2 based on P. If E1 = E2, it is proved that the node entity certificate of the node M is indeed issued by the root CA, and the authenticity of the identity is verified. If E1 ≠ E2, the authentication fails, and a security error is broadcast.

[0059] It should be noted that if any side method or any link fails or the authentication times out, the conversation parties immediately suspend the process, and if the master controller detects a fake node, it will trigger a certificate revocation process, add the certificate of the node to the revocation list, and broadcast to the network to force all communications to be suspended.

[0060] The above method discards the complex three-level architecture under the PKI framework, adopts a two-layer architecture of the master controller and the node, reduces the hierarchical interaction overhead, and first sends a certificate signature request by the node, adopts a signature verification method, establishes a trust chain between the two layers, and then completes the strict identity authentication of the “request-response-confirmation” mechanism based on encryption, decryption, signature and verification of the key at a preset time, which can guarantee the security of data interaction during communication.

[0061] Referring to Figure 2 , Figure 2 is a block diagram of an authentication system provided by an embodiment of the present application. The system is a virtual device that can be loaded and executed by a computer device, and corresponds to the above method, Figure 2 The system can include a master controller side system and a node side system.

[0062] The master controller side system can at least include a trust chain establishment module, a first identity authentication request module and a first identity authentication module.

[0063] The trust chain establishing module extracts a node public key from the certificate signature request in response to receiving the node private key signed certificate signature request, determines a node L sending the certificate signature request according to the node public key, and performs signature verification on the certificate signature request, and if the signature verification is passed, sends the node entity certificate signed by the root certification authority private key to the node L in a frame transmission mode; wherein the node L stores the node entity certificate.

[0064] The first identity authentication request module encrypts the first identity authentication request signed by the root certification authority private key using the node L public key in response to reaching the first preset time, and sends the encrypted first identity authentication request to the node L; wherein the first preset time is the time after the node entity certificate is stored.

[0065] The first identity authentication module decrypts the first identity authentication request response signed by the node L private key using the root certification authority public key in response to receiving the first identity authentication request response signed by the node L private key using the root certification authority public key, and performs signature verification on the decrypted first identity authentication request response using the node L public key, and if the signature verification is passed, feeds back the authentication to the node L.

[0066] The node side system can at least include a certificate signature request module, a node entity certificate verification module, a first identity authentication request response module and an authentication result receiving module.

[0067] The certificate signature request module sends the certificate signature request signed by its own private key to the main controller in a frame transmission mode.

[0068] The node entity certificate verification module performs signature verification on the node entity certificate using the root certification authority public key in response to receiving the node entity certificate signed by the root certification authority private key sent by the main controller, and if the signature verification is passed, stores the node entity certificate.

[0069] The first identity authentication request response module decrypts the first identity authentication request using its own private key in response to receiving the encrypted first identity authentication request sent by the main controller at the first preset time, performs signature verification on the decrypted first identity authentication request using the root certification authority public key, and confirms the legality of the main controller according to the content in the first identity authentication request, and if the signature verification is passed and the main controller is legal, sends the first identity authentication request response signed by its own private key using the root certification authority public key to the main controller; wherein the first preset time is the time after the node entity certificate is stored; the first identity authentication request is the first identity authentication request signed by the root certification authority private key, and the encryption uses the node public key receiving the first identity authentication request.

[0070] The authentication result receiving module receives the authentication result fed back by the main controller according to the first identity authentication request response.

[0071] The hardware architecture corresponding to the above device can be as shown in the figure Figure 3 The above device discards the complex three-level architecture under the PKI framework, adopts a two-layer architecture of a master controller and nodes, reduces the hierarchical interaction overhead, and first sends a certificate signature request by the node, adopts a signature verification method to establish a trust chain between the two layers, and then completes strict identity authentication of the "request-response-confirmation" mechanism based on encryption, decryption, signature, and verification of the key at a preset time, which can guarantee the security of data interaction during communication.

[0072] Based on the above authentication method, the application also relates to a communication method, which mainly completes at least one authentication on the master controller side and the node side before encrypted communication; wherein the master controller side adopts the above master controller side method for authentication, and the node side adopts the above node side method for authentication; if encrypted communication is performed between the master controller and the node, the nonce in the first identity authentication request and the nonce in the first identity authentication request response are spliced to form the key for encrypted communication; if encrypted communication is performed between the nodes, the temporary key obtained based on the entity certificates of the two nodes is used as the key for encrypted communication.

[0073] It should be noted that when encrypted communication is performed between the master controller and the node, in order to improve the real-time communication efficiency of data, a symmetric encryption algorithm can be selected in data transmission, the key for encrypted communication is formed by splicing nonce1 and nonce2, and the key is updated in real time when the next identity verification is performed, so as to prevent replay attacks. In addition, for data with high security, such as power control instructions, encrypted data and hash values can be sent at the same time to confirm that the data has not been tampered with. When encrypted communication is performed between the nodes, a temporary key can be obtained based on the public key obtained from the certificate of the other party to symmetrically encrypt the communication, and the key will also be updated when the next identity authentication is performed, so as to solve the risk of key leakage.

[0074] In actual application, in order to ensure the real-time performance of vehicle control, the controller running period, CAN bus baud rate, and system load rate need to be considered, the identity authentication data interaction can be filled or simplified to balance safety and efficiency.

[0075] The above method integrates identity authentication and data encryption into the same framework, and the private key based on the asymmetric cryptography system is strictly kept secret by the owner, without the need for sharing, which solves the problems of key transfer and key management in traditional secure communication.

[0076] The above method solves the problems of key transfer, identity tracing, and anti-repudiation in traditional secure communication, and provides a trust system based on asymmetric encryption technology for bus communication of construction machinery vehicles.

[0077] The above merely describes the preferred embodiments of the present application, and it should be pointed out that, for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present application, and these improvements and modifications should also be considered as the protection scope of the present application.

Claims

1. An authentication method, characterized in that, The method is implemented in a master controller that integrates a root certification authority, and the method includes: In response to receiving a certificate signing request signed by a node's private key, the node's public key is extracted from the certificate signing request. The node L that sent the certificate signing request is determined based on the node's public key, and the certificate signing request is verified. If the signature verification is successful, the node entity certificate signed by the root certification authority's private key is sent to node L using a framed transmission method. Node L stores the node entity certificate. In response to the arrival of the first preset time, the first identity authentication request signed by the root certification authority's private key using the public key of node L is encrypted, and the encrypted first identity authentication request is sent to node L; wherein, the first preset time is the time after the node entity certificate is stored; In response to receiving a first authentication request response signed by the private key of node L, which is encrypted with the public key of the root certification authority, the first authentication request response is decrypted using the private key of the root certification authority, and the decrypted first authentication request response is signed and verified using the public key of node L. If the signature verification is successful, the authentication is reported back to node L.

2. The method according to claim 1, characterized in that, The node stores a self-signed certificate signed by the root certification authority's private key. The self-signed certificate includes the main controller MCU serial number, the root certification authority's public key, the root certification authority's signature algorithm, and the self-signed certificate's validity period. The certificate signing request includes the node MCU serial number and the node public key; The node entity certificate includes the node MCU serial number, the node public key, and the validity period of the node entity certificate; The first authentication request includes the node entity certificate hash value and the first random number generated by the main controller; The first authentication request response includes the second random number generated by the node, the first random number, and the node MCU serial number.

3. The method according to claim 1, characterized in that, The method further includes: Upon reaching the second preset time, a second authentication request encrypted with an initial pre-shared key is sent to the cloud; wherein, the initial pre-shared key is a new pre-shared key generated when it was last successfully authenticated; In response to receiving a second authentication request response encrypted with the initial pre-shared key from the cloud, the second authentication request response is decrypted using the initial pre-shared key. If the correctness of the decrypted second authentication request response is verified, a new pre-shared key is generated, and a third authentication request encrypted with the new pre-shared key is sent to the cloud. If the system receives feedback from the cloud confirming that the third-party authentication request has been verified as correct, then it confirms that its own authentication has been successful.

4. The method according to claim 3, characterized in that, The second authentication request includes the main controller MCU serial number, the third random number generated by the main controller, and the first timestamp; The second identity authentication request response includes the cloud ID, the third random number generated by the main controller, the fourth random number generated by the cloud, and the second timestamp; The third-party authentication request includes a cloud ID, a cloud-generated fourth random number, a new pre-shared key, and a third timestamp.

5. An authentication system, characterized in that, The system is mounted in a main controller that integrates a root certification authority. The system includes: The trust chain establishment module, in response to receiving a certificate signing request signed by a node's private key, extracts the node's public key from the certificate signing request, determines the node L that sent the certificate signing request based on the node's public key, and verifies the certificate signing request. If the signature verification is successful, it sends the node entity certificate signed by the root certification authority's private key to node L using a framed transmission method; where node L stores the node entity certificate. The first identity authentication request module, in response to the arrival of a first preset time, encrypts the first identity authentication request signed by the root certification authority's private key using the public key of node L, and sends the encrypted first identity authentication request to node L; wherein, the first preset time is the time after the node entity certificate is stored. The first identity authentication module, upon receiving a first identity authentication request response signed by the private key of node L (encrypted with the public key of the root certification authority), decrypts the first identity authentication request response using the private key of the root certification authority and verifies the signature of the decrypted first identity authentication request response using the public key of node L. If the signature verification is successful, it sends a message to node L indicating that authentication has been successful.

6. An authentication method, characterized in that, The method is implemented in a node, wherein the node is connected to the main controller via a bus; the method includes: The certificate signing request, signed with its own private key, is sent to the main controller using a framed transmission method. In response to receiving a node entity certificate signed by the root certification authority's private key from the main controller, the node entity certificate is verified using the root certification authority's public key. If the signature verification passes, the node entity certificate is stored. In response to receiving an encrypted first authentication request from the master controller, the node decrypts the first authentication request using its own private key, verifies the signature of the decrypted first authentication request using the root certification authority's public key, and confirms the legitimacy of the master controller based on the content of the first authentication request. If the signature verification passes and the master controller is legitimate, the node sends a first authentication request response signed by its own private key and encrypted with the root certification authority's public key to the master controller. Here, the first authentication request is a first authentication request signed by the root certification authority's private key, and the encryption uses the public key of the node receiving the first authentication request. Receive the authentication result from the main controller in response to the first identity authentication request.

7. The method according to claim 6, characterized in that, The node stores a self-signed certificate signed by the root certification authority's private key. The self-signed certificate includes the main controller MCU serial number, the root certification authority's public key, the root certification authority's signature algorithm, and the self-signed certificate's validity period. The certificate signing request includes the node MCU serial number and the node public key; The node entity certificate includes the node MCU serial number, the node public key, and the validity period of the node entity certificate; The first authentication request includes the node entity certificate hash value and the first random number generated by the main controller; The first authentication request response includes the second random number generated by the node, the first random number, and the node MCU serial number.

8. The method according to claim 6, characterized in that, The method further includes: In response to the arrival of the third preset time, the node entity certificate of node M is received; wherein, the third preset time is the time after the node entity certificate is stored, the first parameter E1 is calculated based on the content of the node entity certificate of node M and the root certification authority public key, and the second parameter E2 is calculated based on the root certification authority public key. If E1 and E2 are consistent, the authentication is successfully reported to node M; wherein, node M is a node with which there is a communication link.

9. An authentication system, characterized in that, The system is loaded in nodes, wherein the nodes are connected to the main controller via a bus; the system includes: The certificate signing request module sends a certificate signing request signed with its own private key to the main controller using a framed transmission method. The node entity certificate verification module, in response to receiving a node entity certificate signed by the root certification authority's private key sent by the main controller, verifies the node entity certificate using the root certification authority's public key. If the signature verification passes, the node entity certificate is stored. The first authentication request response module, upon receiving an encrypted first authentication request from the main controller at a first preset time, decrypts the first authentication request using its own private key, verifies the signature of the decrypted first authentication request using the root certification authority's public key, and confirms the legitimacy of the main controller based on the content of the first authentication request. If the signature verification passes and the main controller is legitimate, the module sends a first authentication request response signed by its own private key and encrypted with the root certification authority's public key to the main controller. Here, the first preset time is the time after the node entity certificate is stored; the first authentication request is a first authentication request signed with the root certification authority's private key, and encryption uses the public key of the node receiving the first authentication request. The authentication result receiving module receives the authentication result from the main controller in response to the first identity authentication request.

10. A communication method, characterized in that, Before encrypted communication, both the master controller and the node side shall complete at least one authentication; wherein, the master controller side shall perform authentication using the method described in any one of claims 1 to 4, and the node side shall perform authentication using the method described in any one of claims 6 to 8; if the master controller and the node communicate encrypted, the random number in the first authentication request and the random number in the first authentication request response shall be concatenated to form the encryption key; if the nodes communicate encrypted, the temporary key obtained based on the entity certificates of both nodes shall be used as the encryption key.

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