Dynamic management method and system of secret key

Abstract

The invention provides a key dynamic management method and system, and the method comprises the steps: responding to a communication request sent by a vehicle end, and carrying out the validity verification of a vehicle end certificate through a public key of an intermediate certificate authority; after the verification is passed, according to the current network quality parameter and the communication data sensitivity level, determining the target length of the secret key according to a secret key length modulation strategy; and deriving a shared key with a target length through an encryption algorithm by using the vehicle end public key and the cloud end private key, and sending the shared key and the cloud end certificate to the vehicle end. Therefore, the shared key is dynamically adjusted according to the network quality parameter and the communication data sensitivity level, so that the security and efficiency of data transmission can be effectively ensured, and the management complexity is reduced.

Description

Technical Field

[0001] The present application relates to the field of communication information security technology, and in particular to a method and system for dynamic management of keys. Background Art

[0002] With the rapid development of Internet of Vehicles technology, the data interaction between smart vehicles and cloud servers is increasing. Vehicles not only need to share real-time data with the cloud (such as location, speed, and status information), but also need to receive and execute instructions sent by the cloud (such as navigation and fault diagnosis). However, this intensive data interaction also brings unprecedented security challenges, especially in protecting sensitive information such as vehicle control instructions, personal user information, and driving data. Therefore, encryption technology has become crucial.

[0003] In the existing technical solution, a pair of keys (public key and private key) are pre-configured for both parties (cloud and vehicle), and the pair of keys are used for encryption and decryption during the entire communication process. However, static keys may be leaked for various reasons during long-term use, so that communication data can be intercepted, and once the key is leaked or its security is found to be insufficient, the key must be replaced, which often leads to communication interruption and a large amount of management overhead. In large-scale deployment, the management and distribution of static keys will become complicated. Summary of the invention

[0004] In view of this, the purpose of this application is to provide a dynamic key management method and system, which dynamically adjusts the shared key according to network quality parameters and communication data sensitivity level, thereby effectively ensuring the security and efficiency of data transmission and reducing management complexity.

[0005] The embodiment of the present application provides a dynamic management method of a key, which is applied to the cloud. The dynamic management method includes:

[0006] In response to the communication request sent by the vehicle, the legitimacy of the vehicle certificate is verified using the public key of the intermediate certificate authority;

[0007] After verification, the target length of the key is determined according to the key length modulation strategy based on the current network quality parameters and the sensitivity level of the communication data;

[0008] Using the vehicle-side public key and the cloud-side private key, a shared key of the target length is derived through an encryption algorithm, and the shared key and the cloud-side certificate are sent to the vehicle-side.

[0009] Optionally, in response to the communication request sent by the vehicle, using the public key of the intermediate certificate authority to verify the legitimacy of the vehicle certificate includes:

[0010] In response to a communication request sent by the vehicle end, obtaining a vehicle end certificate carried in the communication request;

[0011] Parsing the intermediate certificate issued by the certificate management system, and extracting the public key of the intermediate certificate issuing authority contained in the intermediate certificate;

[0012] Use the public key of the intermediate certificate authority to verify the signature of the vehicle-side certificate;

[0013] After the signature verification is passed, determine whether the vehicle-side certificate is within the validity period;

[0014] If yes, it is determined that the vehicle-side certificate has passed the legitimacy verification.

[0015] Optionally, the management method further includes:

[0016] When the key update conditions are met, in response to the update request sent by the vehicle, the public key of the intermediate certificate authority is used to verify the legitimacy of the vehicle certificate;

[0017] After verification, the update length of the key is determined according to the key length modulation strategy based on the current network quality parameters and the communication data sensitivity level corresponding to the update request;

[0018] Use the vehicle-side public key and the cloud-side private key to derive a shared key with an updated length through an encryption algorithm;

[0019] And use the updated shared key to replace the shared key saved in the vehicle.

[0020] Optionally, the dynamic management method further includes:

[0021] Receiving first interaction data sent by the vehicle end and encrypted by the shared key;

[0022] Decrypting the first interaction data using the shared key;

[0023] Or, use the shared key to encrypt the second interaction data, and send the encrypted second interaction data to the vehicle end.

[0024] The embodiment of the present application also provides a dynamic management method of a key, which is applied to a vehicle side. The dynamic management method includes:

[0025] Send a communication request to the cloud, and at the same time send the vehicle-side certificate, current network quality parameters, and communication data sensitivity level;

[0026] When the cloud verifies the legitimacy of the vehicle-side certificate, it receives the shared key generated by the cloud according to the current network quality parameters and the communication data sensitivity level, and simultaneously receives the cloud certificate.

[0027] Optionally, after receiving the shared key and the cloud certificate generated by the cloud according to the current network quality parameter and the communication data sensitivity level, the dynamic management method further includes:

[0028] Use the public key of the intermediate certificate authority to verify the validity of the cloud certificate;

[0029] After verification, the shared key is stored.

[0030] Optionally, the dynamic management method further includes:

[0031] Receiving second interaction data sent by the cloud and encrypted by the shared key;

[0032] Decrypting the second interaction data using the shared key;

[0033] Or, the first interaction data is encrypted using the shared key, and the encrypted first interaction data is sent to the vehicle end.

[0034] Optionally, the dynamic management method further includes:

[0035] Sending an update request to the cloud, and simultaneously sending the vehicle-side certificate, current network quality parameters, and the communication data sensitivity level corresponding to the update request;

[0036] When the cloud passes the legitimacy verification of the vehicle-side certificate, the cloud receives an update key generated according to the current network quality parameters and the communication data sensitivity level corresponding to the update request, and simultaneously receives the cloud certificate.

[0037] The embodiment of the present application also provides a dynamic key management method, which is applied to a certificate management system. The dynamic management method includes:

[0038] Issue an intermediate certificate authority and an intermediate certificate through a root certificate authority, and pre-set the intermediate certificate in the cloud and vehicle side;

[0039] Issuing a cloud certificate to the cloud through the intermediate certificate authority and generating a public-private key pair for the cloud;

[0040] The intermediate certificate issuing authority issues a vehicle-side certificate to the vehicle-side and generates a public-private key pair for the vehicle-side.

[0041] The embodiment of the present application also provides a dynamic key management system, which includes a vehicle cloud, a vehicle end, and a certificate management system:

[0042] The cloud is used to respond to the communication request sent by the vehicle end, and use the public key of the intermediate certificate authority to verify the legitimacy of the vehicle end certificate; after the verification is passed, according to the current network quality parameters and the sensitivity level of the communication data, the target length of the key is determined according to the key length modulation strategy; using the vehicle end public key and the cloud private key, a shared key of the target length is derived through an encryption algorithm, and the shared key and the cloud certificate are sent to the vehicle end;

[0043] The vehicle side is used to send a communication request to the cloud side, and simultaneously send the vehicle side certificate, the current network quality parameter and the communication data sensitivity level; when the cloud side verifies the legitimacy of the vehicle side certificate, it receives the shared key generated by the cloud side according to the current network quality parameter and the communication data sensitivity level, and simultaneously receives the cloud side certificate;

[0044] The certificate management system is used to issue an intermediate certificate authority and an intermediate certificate through a root certificate authority, and pre-set the intermediate certificate in the cloud and the vehicle; issue a cloud certificate to the cloud through the intermediate certificate authority and generate a public-private key pair for the cloud; issue a vehicle certificate to the vehicle through the intermediate certificate authority and generate a public-private key pair for the vehicle.

[0045] In this way, the present application realizes efficient and secure data transmission in vehicle-cloud communication through a dynamic key negotiation mechanism, effectively solves the security risks brought about by key fixation in the prior art, improves the security and efficiency of data transmission, enhances the intelligence and adaptability of the system, and provides more reliable and secure technical support for the interaction between smart vehicles and cloud servers.

[0046] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 A schematic diagram of the structure of a dynamic key management system provided in an embodiment of the present application;

[0049] Figure 2 A flowchart of a method for dynamic key management when applied to the cloud provided by an embodiment of the present application;

[0050] Figure 3A flowchart of a method for dynamic key management when applied to a vehicle side provided by an embodiment of the present application;

[0051] Figure 4 A flowchart of a method for dynamic key management when applied to a certificate management system provided by an embodiment of the present application;

[0052] Figure 5 A schematic diagram of the implementation process of a dynamic key management method provided in this application. DETAILED DESCRIPTION

[0053] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work belongs to the scope of protection of the present application.

[0054] With the rapid development of Internet of Vehicles technology, the data interaction between smart vehicles and cloud servers is increasing. Vehicles not only need to share real-time data with the cloud (such as location, speed, and status information), but also need to receive and execute instructions sent by the cloud (such as navigation and fault diagnosis). However, this intensive data interaction also brings unprecedented security challenges, especially in protecting sensitive information such as vehicle control instructions, personal user information, and driving data. Therefore, encryption technology has become crucial.

[0055] In the existing technical solution, a pair of keys (public key and private key) are pre-configured for both parties (cloud and vehicle), and the pair of keys are used for encryption and decryption during the entire communication process. However, static keys may be leaked for various reasons during long-term use, so that communication data can be intercepted, and once the key is leaked or its security is found to be insufficient, the key must be replaced, which often leads to communication interruption and a large amount of management overhead. In large-scale deployment, the management and distribution of static keys will become complicated.

[0056] Based on this, an embodiment of the present application provides a dynamic key management method and system, which dynamically adjusts the shared key according to network quality parameters and communication data sensitivity levels, thereby effectively ensuring the security and efficiency of data transmission and reducing management complexity.

[0057] See also Figure 1 , Figure 1 This is a schematic diagram of the structure of a dynamic key management system provided by an embodiment of the present application. Figure 1 As shown in , the dynamic management system 100 provided in the embodiment of the present application includes: a certificate management system 101, a cloud end 102 and a vehicle end 103.

[0058] Here, the certificate management system 101 is a system for generating, managing and issuing digital certificates. The certificate management system 101 in this solution generally includes a root certificate authority (Root CA) and an intermediate certificate authority (Intermediate CA).

[0059] The certificate management system 101 generates, issues and manages digital certificates for the cloud and vehicle in the system, ensuring that the identity of each entity in the system is verified and providing public key infrastructure (PKI) support. In addition, the certificate management system is responsible for managing and distributing public and private key pairs to ensure the reliability and security of the keys.

[0060] The cloud 102 is a remote server or computing platform that communicates with the vehicle end 103 via a network, and is usually used to provide data processing and storage services.

[0061] The vehicle end 103 is a system or module inside the vehicle that has the ability to communicate with the cloud and generally includes a secure hardware module for storing and using certificates and keys.

[0062] In order to ensure the security of data communication between the vehicle side 103 and the cloud side 102, the present application also provides a dynamic key management method, which can dynamically adjust the encryption key according to the network quality parameters and the sensitivity level of the communication data, thereby ensuring the security and efficiency of data transmission.

[0063] For examples, see Figure 2 , Figure 2 This is a flow chart of a method for dynamically managing keys when applied to the cloud provided by an embodiment of the present application. Figure 2 As shown in , when applied to the cloud 102, the dynamic management method provided by the embodiment of the present application includes:

[0064] S201. In response to a communication request sent by the vehicle, the legitimacy of the vehicle certificate is verified using the public key of the intermediate certificate authority.

[0065] S202: After verification, the target length of the key is determined according to the key length modulation strategy based on the current network quality parameters and the communication data sensitivity level.

[0066] S203: Use the vehicle-side public key and the cloud-side private key to derive a shared key of a target length through an encryption algorithm, and send the shared key and the cloud-side certificate to the vehicle-side.

[0067] Here, a key dynamic management method implemented in the cloud is introduced to ensure secure communication between the cloud 102 and the vehicle end 103.

[0068] In step S201, the vehicle 103 initiates a communication request to the cloud 102 and simultaneously sends its own digital certificate (vehicle certificate). The cloud 102 then uses the public key of the intermediate certificate authority to verify the authenticity of the vehicle certificate to ensure the legitimacy and credibility of the vehicle.

[0069] The public key of the intermediate certificate authority may be pre-stored in the cloud 102. The vehicle-side certificate may be issued by an intermediate certificate authority (Intermediate CA), including the public key and identity information of the vehicle-side.

[0070] With respect to step S201, in an implementation manner provided in the present application, in response to the communication request sent by the vehicle, using the public key of the intermediate certificate authority to verify the legitimacy of the vehicle certificate includes:

[0071] S2011. In response to a communication request sent by the vehicle, obtain a vehicle certificate carried in the communication request.

[0072] S2012. Parse the intermediate certificate issued by the certificate management system, and extract the public key of the intermediate certificate issuing authority contained in the intermediate certificate.

[0073] S2013. Use the public key of the intermediate certificate authority to verify the signature of the vehicle-side certificate.

[0074] S2014: After the signature verification is passed, determine whether the vehicle-side certificate is within the validity period.

[0075] S2015: If yes, determine that the vehicle-side certificate passes the legitimacy verification.

[0076] Regarding step S2011, in this step, when the vehicle 103 initiates a communication request to the cloud 102, it will carry its own digital certificate (vehicle certificate, which contains the vehicle's public key, identity information, and the signature of the certificate authority, etc.). The cloud 102 will respond to the communication request of the vehicle 103 and extract the vehicle certificate contained therein for subsequent verification.

[0077] Regarding step S2012, in this step, the cloud 102 extracts the public key of the intermediate certificate authority from the pre-saved intermediate certificate (the intermediate certificate contains the information of the intermediate certificate authority and its public key, and is usually issued by the root certificate authority), so that the public key of the intermediate certificate authority (Intermediate CA) can be used to verify the legitimacy of the vehicle-side certificate.

[0078] With respect to step S2013, the vehicle-side certificate is generally issued by an intermediate certificate authority and therefore contains the digital signature of the authority.

[0079] In this step, the cloud 102 uses the public key of the intermediate certificate authority extracted from the intermediate certificate to verify the digital signature of the vehicle-side certificate to ensure that the certificate is indeed issued by a trusted intermediate certificate authority and that the certificate content has not been tampered with.

[0080] With respect to step S2014, after the signature verification is passed, the cloud 102 checks the validity period field in the vehicle-side certificate to ensure that the vehicle-side certificate is still valid at the current time point to prevent an expired certificate from being used.

[0081] With respect to step S2015 , if the cloud 102 verifies that the signature verification of the vehicle-side certificate is successful and the certificate is within the validity period, the cloud 102 will consider the vehicle-side certificate to be legitimate and allow the vehicle-side 103 to continue with subsequent communication operations.

[0082] Regarding step S202, in this step, after the legitimacy of the vehicle-side certificate is verified, the target length of the key is determined according to the key length modulation strategy based on the current network quality parameters and the communication data sensitivity level.

[0083] The current network quality parameter and the communication data sensitivity level may be sent to the cloud 102 together with the communication request, or the current network quality parameter and the communication data sensitivity level may be embedded in the communication request and sent together to the cloud 102 .

[0084] The current network quality parameters generally include the following parameters:

[0085] Network stability: By real-time monitoring of the quality of the vehicle network connection (such as signal strength, packet loss rate, latency, etc.), the system can determine whether the current network is stable. If the network conditions are good, a longer key can be selected to enhance security; conversely, when the network is unstable, the key length can be appropriately reduced to speed up encryption / decryption and ensure basic communication efficiency.

[0086] Bandwidth resources: adjust the key length according to the available bandwidth. For low-bandwidth or highly congested network environments, using shorter keys can reduce the amount of data transmitted, thereby reducing the network burden. In high-bandwidth environments, longer keys can be used to provide higher security.

[0087] Computing power: Taking into account the computing power and battery life of the onboard equipment, the system can automatically select the appropriate key length based on the actual processing power of the vehicle. Modern vehicles are usually equipped with high-performance processors, but in some cases, in order to save energy, a relatively moderate key length may be selected.

[0088] The communication data sensitivity level may be determined by any of the following methods:

[0089] Data classification: Classify the data generated by the vehicle into, for example, non-sensitive data (such as vehicle location information), medium-sensitive data (such as driving habit analysis), and highly sensitive data (such as personal identity information, payment information). Different levels of data correspond to different key length standards.

[0090] User-defined settings: Allow vehicle owners or operators to set data sensitivity levels based on their own data protection needs. For example, some corporate fleets may require the highest level of protection for all of their vehicle data.

[0091] Context-aware: Determine the sensitivity of data based on the specific context the vehicle is in. For example, certain data, such as in-car camera footage, may be considered less sensitive when the vehicle is parked in a private garage, but more sensitive when the vehicle is on a public road.

[0092] The key length modulation strategy is predetermined, and can be determined by any of the following methods, for example:

[0093] Adaptive algorithm: Develop an intelligent algorithm that can take into account network conditions, data sensitivity, historical attack patterns and other factors to recommend the most appropriate key length in real time. Such an algorithm can continuously learn and optimize its decision-making process through machine learning technology.

[0094] Multi-layer key management: Introducing a multi-layer key management system, that is, configuring different key lengths for different types of data, and these keys can be quickly switched as the environment changes. For example, daily driving data uses a standard key length, while when performing operations involving financial transactions, it is immediately upgraded to a high-level key.

[0095] Regular audit and update: Establish a regular security audit mechanism to check whether the key length currently in use still meets the latest security standards. At the same time, according to the audit results and new threat intelligence, update the system's key length policy in a timely manner.

[0096] Regarding step S203 , in this step, the cloud 102 uses the vehicle-side public key and the cloud-side private key to derive a shared key of a length determined in the previous step through an encryption algorithm, and sends the shared key and the cloud-side certificate to the vehicle-side 103 .

[0097] The encryption algorithm may be an elliptic curve Diffie-Hellman (ECDH) algorithm or other encryption algorithms. The shared key is used to encrypt communication data to ensure transmission security.

[0098] In this way, a secure encrypted channel is established between the vehicle end 103 and the cloud end 102, and subsequent communications will be encrypted using this shared key.

[0099] In another embodiment provided by the present application, the management method further comprises:

[0100] S11. When the key update condition is met, in response to the update request sent by the vehicle, the legitimacy of the vehicle certificate is verified using the public key of the intermediate certificate authority.

[0101] S12. After verification, determine the update length of the updated key according to the key length modulation strategy based on the current network quality parameters and the communication data sensitivity level corresponding to the update request;

[0102] S13, using the vehicle-side public key and the cloud-side private key, derive a shared key with an updated length through an encryption algorithm;

[0103] S14, and use the updated shared key to replace the shared key stored in the vehicle end.

[0104] For step S11, the key update condition may be: when the session ends or the key usage time reaches a time threshold. At this time, the vehicle end 103 sends a key update request to the cloud 102.

[0105] After receiving the update request, the cloud 102 extracts the vehicle-side certificate sent by the vehicle-side, and uses the public key of the intermediate certificate authority (Intermediate CA) to verify the vehicle-side certificate to confirm the legitimacy of the vehicle-side identity.

[0106] Regarding step S12, after the certificate verification is passed, the cloud 102 will evaluate the current network quality (such as latency, bandwidth, etc.) and the sensitivity level of the re-acquired communication data. Based on these parameters, the cloud 102 will determine the update length of the new shared key according to a predefined "key length modulation strategy".

[0107] For step S13, the cloud 102 uses the public key of the vehicle and its own private key to derive a shared key that meets the update length through an encryption algorithm (such as the Elliptic Curve Diffie-Hellman (ECDH) algorithm).

[0108] With respect to step S14 , when a new shared key is generated, the cloud end 102 will send the newly generated shared key to the vehicle end 103 to replace the old shared key previously used by the vehicle end 103 and the cloud end 102 .

[0109] In addition, in another embodiment provided in the present application, the dynamic management method also includes: receiving first interaction data encrypted by the shared key and sent by the vehicle end; decrypting the first interaction data using the shared key; or, encrypting second interaction data using the shared key, and sending the encrypted second interaction data to the vehicle end.

[0110] Here, the vehicle end 103 and the cloud end 102 have established a secure communication channel using a shared key. The data (first interaction data) sent by the vehicle end 103 will be encrypted using the shared key to ensure that the data will not be stolen or tampered with during transmission. The cloud end 102 uses the shared key derived between the vehicle end 103 and the cloud end 102 to decrypt the received first interaction data.

[0111] Alternatively, in two-way communication, the cloud 102 may also need to send data (second interactive data) to the vehicle 103, and the cloud 102 will use the same shared key to encrypt the data to ensure that the data will not be tampered with or leaked during transmission.

[0112] The above content describes the dynamic management process of the key when applied to the cloud 102. This solution also provides the dynamic management process of the key when applied to the vehicle 103.

[0113] For examples, see Figure 3 , Figure 3 This is a flow chart of a method for dynamic key management applied to a vehicle end provided by an embodiment of the present application. Figure 3 As shown in , when applied to the vehicle end 103, the dynamic management method provided by the embodiment of the present application includes:

[0114] S301. Send a communication request to the cloud, and at the same time send the vehicle-side certificate, current network quality parameters, and communication data sensitivity level.

[0115] S302. After the cloud passes the legitimacy verification of the vehicle-side certificate, the cloud receives a shared key generated by the cloud according to current network quality parameters and communication data sensitivity level, and simultaneously receives a cloud certificate.

[0116] For step S301, when the vehicle-side 103 initiates communication, it will send a communication request to the cloud-side 102, requesting to establish a secure communication channel with the cloud-side 102. In this communication request, the vehicle-side 103 will also send some key information, including: a vehicle-side certificate (used to prove the identity and legitimacy of the vehicle-side 103), current network quality parameters (describing the current network status), and communication data sensitivity level (indicating the sensitivity of the communication data this time).

[0117] For step S302, after receiving the communication request from the vehicle 103, the cloud 102 first verifies the legitimacy of the vehicle certificate to ensure that the vehicle is a trusted device. After the vehicle certificate is verified, the cloud generates a shared key based on the current network quality parameters and the sensitivity level of the communication data. The vehicle 103 receives the shared key and cloud certificate sent by the cloud. In this way, the vehicle 103 can verify the identity of the cloud 102 through the cloud certificate.

[0118] After executing step S302, the dynamic management method further includes: using the public key of the intermediate certificate authority to verify the validity of the cloud certificate; after the verification is passed, storing the shared key.

[0119] Here, when the vehicle end 103 receives the cloud certificate sent by the cloud 102, in order to ensure the legitimacy and credibility of the cloud 102, the vehicle end 103 uses the public key of the intermediate certificate authority (Intermediate CA) to check whether the digital signature of the cloud certificate is valid. After the cloud certificate is verified, the vehicle end 103 can confirm that the identity of the cloud 102 is credible, and the vehicle end 103 safely stores the shared key generated by the cloud 102. The shared key will be used to encrypt and decrypt data in the subsequent communication process.

[0120] In addition, in another embodiment provided in the present application, the dynamic management method also includes: receiving second interaction data encrypted by the shared key and sent by the cloud; decrypting the second interaction data using the shared key; or, encrypting the first interaction data using the shared key, and sending the encrypted first interaction data to the vehicle end.

[0121] Here, the vehicle end 103 and the cloud end 102 have established a secure communication channel using a shared key. The data (second interactive data) sent by the cloud end 102 will be encrypted using the shared key to ensure that the data will not be stolen or tampered with during transmission. The vehicle end 103 uses the shared key derived between the vehicle end 103 and the cloud end 102 to decrypt the received second interactive data.

[0122] Alternatively, in two-way communication, the vehicle end 103 may also need to send data (first interaction data) to the vehicle end 102, and the vehicle end 103 will use the same shared key to encrypt the data to ensure that the data will not be tampered with or leaked during transmission.

[0123] In another embodiment provided in the present application, the dynamic management method also includes: sending an update request to the cloud, and simultaneously sending the vehicle-side certificate, the current network quality parameters, and the communication data sensitivity level corresponding to the update request; when the cloud passes the legitimacy verification of the vehicle-side certificate, receiving the update key generated by the cloud based on the current network quality parameters and the communication data sensitivity level corresponding to the update request, and simultaneously receiving the cloud certificate.

[0124] This part of the content corresponds to steps S11-S14 and will not be repeated here.

[0125] The above content describes the dynamic management process of keys when applied to the vehicle end 103. This solution also provides the dynamic management process of keys when applied to the certificate management system 101.

[0126] For examples, see Figure 4 , Figure 4 The present invention provides a flowchart of a method for dynamically managing keys when applied to a certificate management system. Figure 4 As shown in , when applied to the certificate management system 101, the dynamic management method provided by the embodiment of the present application includes:

[0127] S401. Issue an intermediate certificate authority and an intermediate certificate through a root certificate authority, and pre-set the intermediate certificate in the cloud and the vehicle.

[0128] S402, issuing a cloud certificate to the cloud through the intermediate certificate authority and generating a public-private key pair for the cloud;

[0129] S403: issuing a vehicle-side certificate to the vehicle-side through the intermediate certificate issuing authority and generating a public-private key pair for the vehicle-side.

[0130] For step S401, the root certificate authority (Root CA) is the highest level of trust authority in the entire certificate chain, and it is responsible for issuing and managing intermediate certificate authorities. The root certificate authority will issue a certificate to the intermediate certificate authority (Intermediate CA) to prove that the intermediate certificate authority is trustworthy. The intermediate certificate is issued by the root certificate authority and is used to authenticate and manage the certificates on the cloud and the vehicle. The issued intermediate certificate will be preset on the cloud and the vehicle, so that both parties can use the intermediate certificate for mutual authentication and establish secure communication.

[0131] With respect to step S402, the intermediate certificate issuing authority issues a cloud certificate to the cloud 102 through its intermediate certificate, and generates a pair of public and private keys for the cloud 102. The cloud certificate includes the public key of the cloud 102 and its identity information.

[0132] For step S403, the intermediate certificate issuing authority issues a vehicle-side certificate to the vehicle-side 103 through its intermediate certificate, and generates a pair of public and private keys for the vehicle-side 103. The vehicle-side certificate includes the public key of the vehicle-side 103 and its identity information.

[0133] In this way, through the cooperation among the certificate management system 101, the cloud 102 and the vehicle 103, dynamic management of keys is achieved, thereby realizing secure communication between the vehicle and the cloud.

[0134] For examples, see Figure 5 , Figure 5 The following is a schematic diagram of the implementation process of a dynamic key management method provided by this application. Figure 5 As shown, the implementation process is specifically divided into the following aspects:

[0135] 1. Establishment of certificate management system

[0136] Establishment of Root CA (Root Certificate Authority): Establish a widely trusted Root CA to generate and manage root certificates. This root certificate is the trust base of the entire certificate chain. Root CA generates a pair of public and private keys, and the private key is securely stored and used to issue certificates of Intermediate CA (Intermediate Certificate Authority).

[0137] Deployment of Intermediate CA: Based on the certificate issued by Root CA, Intermediate CA is established to issue certificates for cloud services and vehicles. Intermediate CA also corresponds to a pair of public and private keys. The private key is securely stored and used to issue digital certificates for vehicles and the cloud.

[0138] Issuance of vehicle and cloud certificates: Generate a unique public-private key pair for each registered vehicle, and use the private key of the Intermediate CA to issue the vehicle certificate. The cloud service also generates a unique public-private key pair and uses the private key of the Intermediate CA to issue the cloud certificate.

[0139] 2. Dynamic key negotiation process

[0140] When the vehicle needs to communicate with the cloud, the vehicle first initiates a connection request and sends its own certificate to the cloud along with the request.

[0141] After receiving the vehicle certificate, the cloud uses the Intermediate CA's public key to verify the validity of the vehicle certificate and confirm the legitimacy of the vehicle's identity.

[0142] After verification, the cloud uses the vehicle's public key and its own private key, and dynamically derives a shared key through the Elliptic Curve Diffie-Hellman (ECDH) algorithm based on the current network quality parameters and the sensitivity level of the communication data. The key length is set according to the sensitivity of the data, for example, a longer key length is used for highly sensitive data.

[0143] The cloud encrypts the derived encryption key and its own certificate and sends them to the vehicle. The vehicle uses the Intermediate CA's public key to verify the validity of the cloud certificate and temporarily stores the encryption key.

[0144] 3. Data encryption and decryption and key update

[0145] In the subsequent communication process, both the vehicle and the cloud use this dynamically generated encryption key to encrypt and decrypt data to ensure the confidentiality of the data. The two parties exchange information such as vehicle status and control instructions through an encrypted communication channel.

[0146] When the communication session ends or the encryption key is about to expire, the two parties will re-perform the key negotiation process to generate a new encryption key. After the new key is generated, it will immediately replace the old key and continue to be used for subsequent communications to ensure the continued security and efficiency of communication.

[0147] Thus, the technical solution of the present application has the following differences and advantages compared with the prior art:

[0148] Enhanced security: From certificate verification to key negotiation, and then to data encryption and decryption, dynamic key updates reduce the possibility of keys being used for a long time. Even if the keys are intercepted, due to the rapid rotation of the keys, the effective time window that attackers can exploit is very short, thus achieving end-to-end security of vehicle-cloud communications.

[0149] Dual certificate system: The introduction of a dual-tier certificate system consisting of Root CA (Root Certificate Authority) and Intermediate CA (Intermediate Certificate Authority) enhances the flexibility and security of certificate management.

[0150] Dynamic key negotiation: The ECDH algorithm is used to dynamically derive and update keys, which not only ensures the confidentiality and uniqueness of the keys, but also improves communication efficiency.

[0151] Adaptive update strategy: It can decide when to update the key based on real-time monitored changes in the network environment or potential threats, which can ensure security and save resources.

[0152] Simplify key management and improve availability: By automating the key update process, the burden of key management is reduced, the possibility of misoperation is reduced, and the communication interruption time caused by key update is reduced, thereby improving service continuity and availability.

[0153] The embodiment of the present application further provides a cloud, wherein the cloud is used for:

[0154] In response to the communication request sent by the vehicle, the legitimacy of the vehicle certificate is verified using the public key of the intermediate certificate authority;

[0155] After verification, the target length of the key is determined according to the key length modulation strategy based on the current network quality parameters and the sensitivity level of the communication data;

[0156] Using the vehicle-side public key and the cloud-side private key, a shared key of the target length is derived through an encryption algorithm, and the shared key and the cloud-side certificate are sent to the vehicle-side.

[0157] Optionally, when the cloud is used to respond to the communication request sent by the vehicle and use the public key of the intermediate certificate authority to verify the legitimacy of the vehicle certificate, the cloud is used to:

[0158] In response to a communication request sent by the vehicle end, obtaining a vehicle end certificate carried in the communication request;

[0159] Parsing the intermediate certificate issued by the certificate management system, and extracting the public key of the intermediate certificate issuing authority contained in the intermediate certificate;

[0160] Use the public key of the intermediate certificate authority to verify the signature of the vehicle-side certificate;

[0161] After the signature verification is passed, determine whether the vehicle-side certificate is within the validity period;

[0162] If yes, it is determined that the vehicle-side certificate has passed the legitimacy verification.

[0163] Optionally, the cloud is also used for:

[0164] When the key update conditions are met, in response to the update request sent by the vehicle, the public key of the intermediate certificate authority is used to verify the legitimacy of the vehicle certificate;

[0165] After verification, the update length of the key is determined according to the key length modulation strategy based on the current network quality parameters and the communication data sensitivity level corresponding to the update request;

[0166] Use the vehicle-side public key and the cloud-side private key to derive a shared key with an updated length through an encryption algorithm;

[0167] And use the updated shared key to replace the shared key saved in the vehicle.

[0168] Optionally, the cloud is also used for:

[0169] Receiving first interaction data sent by the vehicle end and encrypted by the shared key;

[0170] Decrypting the first interaction data using the shared key;

[0171] Or, use the shared key to encrypt the second interaction data, and send the encrypted second interaction data to the vehicle end.

[0172] The embodiment of the present application further provides a vehicle end, wherein the vehicle end is used for:

[0173] Send a communication request to the cloud, and at the same time send the vehicle-side certificate, current network quality parameters, and communication data sensitivity level;

[0174] When the cloud verifies the legitimacy of the vehicle-side certificate, it receives the shared key generated by the cloud according to the current network quality parameters and the communication data sensitivity level, and simultaneously receives the cloud certificate.

[0175] Optionally, the vehicle end is also used for:

[0176] After receiving the shared key and the cloud certificate generated by the cloud according to the current network quality parameters and the communication data sensitivity level, verify the validity of the cloud certificate using the public key of the intermediate certificate authority;

[0177] After verification, the shared key is stored.

[0178] Optionally, the vehicle end is also used for:

[0179] Receiving second interaction data sent by the cloud and encrypted by the shared key;

[0180] Decrypting the second interaction data using the shared key;

[0181] Or, the first interaction data is encrypted using the shared key, and the encrypted first interaction data is sent to the vehicle end.

[0182] Optionally, the vehicle end is also used for:

[0183] Sending an update request to the cloud, and simultaneously sending the vehicle-side certificate, current network quality parameters, and the communication data sensitivity level corresponding to the update request;

[0184] When the cloud passes the legitimacy verification of the vehicle-side certificate, the cloud receives an update key generated according to the current network quality parameters and the communication data sensitivity level corresponding to the update request, and simultaneously receives the cloud certificate.

[0185] The present application also provides a certificate management system, which is used to:

[0186] Issue an intermediate certificate authority and an intermediate certificate through a root certificate authority, and pre-set the intermediate certificate in the cloud and vehicle side;

[0187] Issuing a cloud certificate to the cloud through the intermediate certificate authority and generating a public-private key pair for the cloud;

[0188] The intermediate certificate issuing authority issues a vehicle-side certificate to the vehicle-side and generates a public-private key pair for the vehicle-side.

[0189] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0190] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0191] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0192] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0193] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application can essentially be embodied in the form of a software product, or in other words, the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0194] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-mentioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for dynamic management of keys, characterized in that: Applied to the cloud, the dynamic management method includes: In response to the communication request sent by the vehicle, the legitimacy of the vehicle certificate is verified using the public key of the intermediate certificate authority; After verification, the target length of the key is determined according to the key length modulation strategy based on the current network quality parameters and the sensitivity level of the communication data; Using the vehicle-side public key and the cloud-side private key, a shared key of the target length is derived through an encryption algorithm, and the shared key and the cloud-side certificate are sent to the vehicle-side.

2. The dynamic management method according to claim 1, characterized in that: The responding to the communication request sent by the vehicle end, using the public key of the intermediate certificate issuing authority to verify the legitimacy of the vehicle end certificate, includes: In response to a communication request sent by the vehicle end, obtaining a vehicle end certificate carried in the communication request; Parsing the intermediate certificate issued by the certificate management system, and extracting the public key of the intermediate certificate issuing authority contained in the intermediate certificate; Use the public key of the intermediate certificate authority to verify the signature of the vehicle-side certificate; After the signature verification is passed, determine whether the vehicle-side certificate is within the validity period; If yes, it is determined that the vehicle-side certificate has passed the legitimacy verification.

3. The management method according to claim 1, characterized in that: The management method also includes: When the key update conditions are met, in response to the update request sent by the vehicle, the public key of the intermediate certificate authority is used to verify the legitimacy of the vehicle certificate; After verification, the update length of the key is determined according to the key length modulation strategy based on the current network quality parameters and the communication data sensitivity level corresponding to the update request; Use the vehicle-side public key and the cloud-side private key to derive a shared key with an updated length through an encryption algorithm; And use the updated shared key to replace the shared key saved in the vehicle.

4. The dynamic management method according to claim 1, characterized in that: The dynamic management method further comprises: Receiving first interaction data sent by the vehicle end and encrypted by the shared key; Decrypting the first interaction data using the shared key; Or, the second interaction data is encrypted using the shared key, and the encrypted second interaction data is sent to the vehicle end.

5. A method for dynamic management of keys, characterized in that: Applied to the vehicle side, the dynamic management method includes: Send a communication request to the cloud, and at the same time send the vehicle-side certificate, current network quality parameters, and communication data sensitivity level; When the cloud verifies the legitimacy of the vehicle-side certificate, it receives the shared key generated by the cloud according to the current network quality parameters and the communication data sensitivity level, and simultaneously receives the cloud certificate.

6. The dynamic management method according to claim 5, characterized in that: After receiving the shared key and the cloud certificate generated by the cloud according to the current network quality parameter and the communication data sensitivity level, the dynamic management method further includes: Use the public key of the intermediate certificate authority to verify the validity of the cloud certificate; After verification, the shared key is stored.

7. The dynamic management method according to claim 6, characterized in that: The dynamic management method further comprises: Receiving second interaction data sent by the cloud and encrypted by the shared key; Decrypting the second interaction data using the shared key; Or, the first interaction data is encrypted using the shared key, and the encrypted first interaction data is sent to the vehicle end.

8. The dynamic management method according to claim 5, characterized in that: The dynamic management method also includes: Sending an update request to the cloud, and simultaneously sending the vehicle-side certificate, current network quality parameters, and the communication data sensitivity level corresponding to the update request; When the cloud passes the legitimacy verification of the vehicle-side certificate, the cloud receives an update key generated according to the current network quality parameters and the communication data sensitivity level corresponding to the update request, and simultaneously receives the cloud certificate.

9. A method for dynamic management of keys, characterized in that: Applied to a certificate management system, the dynamic management method includes: Issue an intermediate certificate authority and an intermediate certificate through a root certificate authority, and pre-set the intermediate certificate in the cloud and vehicle side; Issuing a cloud certificate to the cloud through the intermediate certificate authority and generating a public-private key pair for the cloud; The intermediate certificate issuing authority issues a vehicle-side certificate to the vehicle-side and generates a public-private key pair for the vehicle-side.

10. A dynamic key management system, characterized in that: The dynamic management system includes the vehicle cloud, vehicle end and certificate management system: The cloud is used to respond to the communication request sent by the vehicle end, and use the public key of the intermediate certificate authority to verify the legitimacy of the vehicle end certificate; after the verification is passed, according to the current network quality parameters and the sensitivity level of the communication data, the target length of the key is determined according to the key length modulation strategy; using the vehicle end public key and the cloud private key, a shared key of the target length is derived through an encryption algorithm, and the shared key and the cloud certificate are sent to the vehicle end; The vehicle side is used to send a communication request to the cloud side, and simultaneously send the vehicle side certificate, the current network quality parameter and the communication data sensitivity level; when the cloud side verifies the legitimacy of the vehicle side certificate, it receives the shared key generated by the cloud side according to the current network quality parameter and the communication data sensitivity level, and simultaneously receives the cloud side certificate; The certificate management system is used to issue an intermediate certificate authority and an intermediate certificate through a root certificate authority, and pre-set the intermediate certificate in the cloud and the vehicle; issue a cloud certificate to the cloud through the intermediate certificate authority and generate a public-private key pair for the cloud; issue a vehicle certificate to the vehicle through the intermediate certificate authority and generate a public-private key pair for the vehicle.

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