Multi-level key dispersion method supporting cross-domain interoperation of tunnel electromechanical system

Abstract

The invention discloses a multi-level key dispersion method supporting tunnel electromechanical system cross-domain interoperation. The method comprises the steps that a trusted center generates a non-singular elliptic curve parameter, a system main private key and a system public key and then issues a public parameter; safely distributing to the tunnel electromechanical equipment through the tunnel management center; the tunnel electromechanical equipment combines a traceable identifier, a provincial domain identifier, a city domain identifier and a tunnel identifier to construct a dispersion factor; based on a dispersion factor, a part of private keys and a self-selected private key of the equipment, a unique session key and an authentication key are derived through a national cryptographic hash function to realize strong binding between the key and the physical position and management attribution of the equipment; according to the method, the device key is strongly bound with the physical position and the management attribution of the device key through the hash function, the problems of identity mutual trust and risk isolation in cross-domain interoperation are solved, the calculation and communication overhead of resource-limited industrial devices is reduced, and the problem of high-performance security protocol application of embedded devices is solved.

Description

Technical Field

[0001] This invention relates to the field of key distribution technology, and in particular to a multi-level key distribution method that supports cross-domain interoperability of tunnel electromechanical systems. Background Technology

[0002] Currently, highway tunnel electromechanical systems lack a systematic overall solution for secure data transmission. Existing systems mostly use simple fixed passwords or pre-shared keys for device authentication and communication encryption. This approach suffers from static key settings that remain unchanged over a long period, and the same key is often reused across multiple devices, making it difficult to achieve the goal of "one key per device." Once a key is leaked, attackers can use it to access multiple devices, causing widespread security risks. Secondly, traditional solutions struggle to support interoperability between devices across tunnels and regions. Due to the lack of device identity trust mechanisms between different management domains, authentication and key negotiation cannot be seamlessly performed, hindering data sharing and business collaboration.

[0003] Furthermore, highway tunnels contain a large number of electromechanical devices in complex environments, and most of these devices are resource-constrained embedded terminals that cannot handle the heavy burden of certificate management and cryptographic operations inherent in traditional public key infrastructures. Although some technologies have attempted to use national cryptographic algorithms to achieve dynamic key management (such as CN118074976A) and ensure data security at the node layer (CN202311169768.7), none of them have proposed cross-domain interoperability, lightweight authentication, and key distribution mechanisms for highway tunnel electromechanical systems, and in particular, they lack a comprehensive design that combines multi-level regional factor binding with lightweight certificates.

[0004] Therefore, in the resource-constrained electromechanical environment of highway tunnels, it is imperative to build a secure communication system that simultaneously possesses high-strength identity authentication, dynamic key updates, and refined key distribution capabilities supporting cross-domain interoperability, while complying with national cryptographic standards. Consequently, there is an urgent need for a new key management and distribution mechanism that is deeply optimized for this scenario to address the aforementioned pain points and comprehensively enhance the network security protection capabilities of highway tunnel electromechanical systems. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-level key distribution method that supports cross-domain interoperability of tunnel electromechanical systems.

[0006] To achieve the above objectives, the present invention is implemented according to the following technical solution:

[0007] This invention includes the following steps:

[0008] S1 system initialization phase:

[0009] The Trusted Center generates non-singular elliptic curve parameters, the system master private key, and the system public key, and then publishes the public parameters.

[0010] The tunnel electromechanical equipment submits hardware identifiers and tunnel identifiers to the tunnel management center in the corresponding area. The tunnel management center forwards the registration information to the trusted center and then verifies and generates a partial private key and traceable device identifier corresponding to the tunnel electromechanical equipment. These are then securely distributed to the tunnel electromechanical equipment through the tunnel management center.

[0011] S2 multi-level geographical key distribution stage:

[0012] The tunnel electromechanical equipment combines traceability identifiers, provincial identifiers, municipal identifiers, and tunnel identifiers to construct a dispersion factor;

[0013] Based on the dispersion factor, partial private key and device-selected private key, a unique session key and authentication key are derived through the national cryptographic hash function to achieve a strong binding between the key and the physical location and management ownership of the device;

[0014] S3 cross-domain data interoperability phase:

[0015] The first regional device and the second regional controller use the national cryptographic SM2 algorithm for bidirectional authentication, and independently calculate the same session key based on the negotiated shared key and regional dispersion factor, and use the SM4 algorithm to encrypt communication.

[0016] Furthermore, in the device registration phase, the step of verifying the validity of a portion of the private key includes:

[0017] Check if the scalar product of the partial private key and the base point is equal to a linear combination of the device public key and the system public key. If it is true, accept it; otherwise, discard it.

[0018] Furthermore, the trusted center randomly selects elliptic curve parameters and a master private key, calculates the system public key, and generates public parameters, which include elliptic curve parameters, the system public key, and a hash function; the hash function... to All are implemented using the national cryptographic SM3 algorithm, and the hash function includes:

[0019] ,

[0020] ,

[0021] ,

[0022] ,

[0023] ,

[0024] in, Indicates the bit length of the negotiation key.

[0025] Furthermore, in the multi-level geographical key distribution stage:

[0026] The complete private key of a device consists of a partial private key and a self-selected private key, and the corresponding public key is the scalar product of the self-selected private key and the base point.

[0027] The session key and authentication key are generated by jointly calculating the dispersion factor, a portion of the private key, and a self-selected private key using the national cryptographic SM3 hash function.

[0028] Furthermore, the cross-domain data interoperability phase specifically includes:

[0029] Device A uses the full private key to perform an SM2 signature on the timestamp and encrypted identity information;

[0030] b. The controller verifies the validity of the signature by calculating whether the relationship between the signature value and the device public key material holds true.

[0031] c. Both parties communicate using encrypted encryption based on the derived session key and the SM4 algorithm.

[0032] Furthermore, the Trusted Center or Tunnel Management Center periodically issues key update instructions, and the device generates a new private key and session key; when a device is identified as malicious, the Trusted Center queries its true identity based on the traceable identifier and adds it to the blacklist.

[0033] Furthermore, the elliptic curve is randomly selected from the non-singular curves recommended by the Chinese national cryptographic standard SM2, satisfying the equation y²=x³+ax+bmodp, and the discriminant 4a³+27b²≠0, where... p is a large prime number.

[0034] Furthermore, the tunnel electromechanical equipment includes sensors, actuators, lighting equipment, or fan controllers.

[0035] Furthermore, the key update steps during cross-domain migration of the tunnel electromechanical equipment are as follows:

[0036] When the tunnel electromechanical equipment is moved from the first region to the second region, the tunnel management center in the second region initiates a migration authorization request to the trusted center.

[0037] After the trusted center verifies the device, the hardware identifier and some private keys remain unchanged. Only the associated geographical dispersion factor is updated to the provincial identifier, city identifier and tunnel identifier of the second region.

[0038] After the tunnel electromechanical equipment is powered on in the second region, it re-derives a new session key based on the new regional dispersion factor and completes authentication and communication with the system in the second region.

[0039] Furthermore, in the multi-level geographical key distribution step, the formula for the device to derive the session key is:

[0040]

[0041] H4 is the SM3 hash function, and xi is the personalized private key selected by the device.

[0042] The beneficial effects of this invention are:

[0043] This invention solves the problems of identity trust and risk isolation in cross-domain interoperability by strongly binding device keys to their physical location and management ownership through hash functions. Based on a lightweight pseudonymous certificate-based authentication and key negotiation protocol, it supports on-demand key updates and secure traceability, effectively ensuring the forward security and ease of operation and maintenance of the system. While meeting the security strength of national cryptographic algorithms, it reduces the computing and communication overhead of resource-constrained industrial equipment and solves the problem of high-performance security protocols for embedded device applications. Attached Figure Description

[0044] Figure 1 This is an application scenario for data transmission interoperability in tunnel electromechanical systems provided in this embodiment of the invention;

[0045] Figure 2 This is an overall flowchart of cross-domain data interoperability of the electromechanical system of a highway tunnel provided in an embodiment of the present invention;

[0046] Figure 3 This is a flowchart of the method for dynamically distributing cross-domain interoperability keys for highway tunnel electromechanical systems provided in this embodiment of the invention;

[0047] Figure 4 This is a schematic diagram of the dynamic distribution principle of multi-level regional keys for highway tunnel electromechanical system data provided in an embodiment of the present invention. Detailed Implementation

[0048] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. The illustrative embodiments of the invention are provided to explain the invention, but are not intended to limit the invention.

[0049] like Figure 1 As shown, the present invention includes the following steps: S1 System initialization phase:

[0050] The Trusted Center generates non-singular elliptic curve parameters, the system master private key, and the system public key, and then publishes the public parameters.

[0051] The tunnel electromechanical equipment submits hardware identifiers and tunnel identifiers to the tunnel management center in the corresponding area. The tunnel management center forwards the registration information to the trusted center and then verifies and generates a partial private key and traceable device identifier corresponding to the tunnel electromechanical equipment. These are then securely distributed to the tunnel electromechanical equipment through the tunnel management center.

[0052] S2 multi-level geographical key distribution stage:

[0053] The tunnel electromechanical equipment combines traceability identifiers, provincial identifiers, municipal identifiers, and tunnel identifiers to construct a dispersion factor;

[0054] Based on the dispersion factor, partial private key and device-selected private key, a unique session key and authentication key are derived through the national cryptographic hash function to achieve a strong binding between the key and the physical location and management ownership of the device;

[0055] S3 cross-domain data interoperability phase:

[0056] The first regional device and the second regional controller use the national cryptographic SM2 algorithm for bidirectional authentication, and independently calculate the same session key based on the negotiated shared key and regional dispersion factor, and use the SM4 algorithm to encrypt communication.

[0057] like Figure 2 As shown, it includes five stages: system initialization, device and certificate distribution, key distribution and derivation, authentication and secure communication within the tunnel, and key update and traceability. The entire process follows the national cryptographic standards SM2 and SM4.

[0058] Step 1: The Trusted Center (CA) is responsible for the global initialization of the system, generating the system master key and public parameters;

[0059] 1) CA randomly selects a non-singular elliptic curve recommended by the national cryptographic standard SM2. ,in , p is a large prime number;

[0060] 2) A q-order cyclic group G is formed by the points on the elliptic curve E and the point O at infinity. The generator P of G is randomly selected.

[0061] 3) CA is randomly selected Used as the system's master private key, and used to calculate the system's public key. ,in s and s are the system's public key and private key, respectively;

[0062] 4) The CA selects a series of national cryptographic hash functions and cryptographic algorithms. , , , , ;

[0063] 5) CA Public System Common Parameters: The system master private key s is strictly stored in the Hardware Security Module (HSM);

[0064] Step 2: Before the tunnel electromechanical equipment is manufactured or deployed, it must be registered with the Tunnel Management Center (TMC) to which it belongs, and a lightweight pseudonym certificate must be issued by the CA.

[0065] 6) Registration Request: Device Its unique hardware identifier Serial number and associated tunnel code Send to the corresponding tunnel management center, denoted as . Generate registration information ;

[0066] 7) Relay request: Use secure channels Forwarded to the Trusted Center (CA);

[0067] 8) Random selection Calculate the partial public key point: Generate device traceability identifiers This pseudonym is fixed and used for CA tracing. Calculate the verification parameters: ,in It's the certificate validity period, then we calculate part of the private key; CA stores a traceable list locally. ;

[0068] 9) Certificate Distribution: The CA will distribute the certificate via a secure channel. Send to , and then by Safely injected into the device In the hardware security module HSM;

[0069] 10) Step Three: Multi-level Geographic Key Distribution and Derivation: After startup, device Di uses a portion of the private key PSKi issued by the CA and securely stored in the HSM, the selected personalized private key xi, and multi-level geographic distribution factors to derive a unique communication key locally. For example... Figure 3 The diagram illustrates the entire process of dynamic key distribution and authentication in the electromechanical system of a highway tunnel.

[0070] 11) Equipment receive Next, first verify its validity and check. Check if the condition is met; if so, accept the data; otherwise, discard it.

[0071] 12) Generate a device-specific key pair, device Choose for yourself As its personalized private key, and calculate the corresponding Its complete private key is ;

[0072] 13) Construct a dispersion factor, combined with the equipment Construct its unique dispersion factor using its provincial ID, city ID, and tunnel ID. ;

[0073] 14) Derive the session key using the SM3 hash function (Chinese national cryptographic standard), based on the dispersion factor, a portion of the private key, and the personalized private key. and authentication key AK, , This mechanism ensures "one machine, one key, one domain," meaning that even equipment manufactured in the same batch will use different keys in different tunnels.

[0074] Step 4: Establish a secure communication link between the equipment and the controller within the tunnel, such as... Figure 4 As shown, the core logic of key derivation and verification is illustrated.

[0075] 15) Equipment When communication with controller C is required, an authentication request message is generated;

[0076] 16) Use your own complete private key For the current timestamp and Perform SM2 signing. ;

[0077] 17) Send a request message { Give it to the controller;

[0078] 18) Controller C verifies timestamp Freshness;

[0079] 19) Verify the signature using the device's public key material. The validity of the formula The validity of the signature is determined by calculating whether they are equal. Represents the hash digest of the message. It is the signature value extracted from the message, where M is the plaintext of the message. ;

[0080] 20) After successful verification, controller C decrypts using its private key. ,get This confirms the device's identity.

[0081] 21) Controller C according to Using the same key distribution algorithm as the device and the known geographic coding, the same session key is calculated. and authentication key AK;

[0082] 22) Subsequently, both sides used the derived... Encrypted data communication is performed using the national cryptographic algorithm SM4, and message integrity is verified using the authentication key AK.

[0083] Step 5: Key Update and Traceability;

[0084] 23) Key Update and Traceability: Alternatively, the CA can periodically issue key update commands. These new commands are encrypted using the device's current valid public key and broadcast. Upon receiving the command, the device securely executes the key update algorithm within the HSM to generate a new key. and To achieve forward security of the key;

[0085] 24) When a traceable device identifier When the corresponding device is identified as malicious, the tunnel management center This can be Report to CA. CA uses the locally stored traceability list. The device's true identity can be found immediately. and its associated tunnels They will add them to the blacklist and revoke their certificates.

[0086] In this embodiment, the implementation process of this method is illustrated by taking the example of a sensing device in tunnel B (city B, province A) sending a coordination command to an execution device in tunnel A (city D, province C):

[0087] System initialization and device registration: The Trusted Center (CA) generates a master key pair for the entire system. (D City Cloud Control Center (TMC)) TY ) and City B Cloud Control Center (TMC) SJZ Each entity registers with a CA and obtains its respective management domain certificate.

[0088] Key distribution and geographic binding: First, a key is generated for the sensing device, and the CA is the sensor (assuming HWID). i Generate a partial private key PSK for SN-123) i And combined with its geographical factors (e.g., Province A ID=13, City B ID=01, Tunnel BID=002), its traceability identifier PID is calculated. i Ultimately, its communication key is determined by formula SK. session =SM3(PID i ||13||01||002||PSK i ||x i It is derived from ).

[0089] Generate a key for the execution device in City D: Similarly, the execution device key for City D is derived from its geographical factors (C Province ID=14, City D ID=01, Tunnel AID=001).

[0090] The sensing equipment in Tunnel B detected an abnormal environmental indicator, signed the data using a key derived from the geographical factor of "Province A, City B", and then combined the data, signature, and its traceable identifier PID. i The region factor (13,01,002) is also sent to the D cloud control center.

[0091] After receiving the request, the D City Cloud Control Center extracted the regional factor and traceable identifier and submitted it to the CA for cross-domain legality verification. The CA verified that the certificate was indeed signed by it and that its registered regional information completely matched the regional factor (13,01,002) in the message.

[0092] Once the verification is successful, the D City Cloud Control Center can trust that the data indeed comes from a legitimate device under the jurisdiction of B City, A Province, and is not from a counterfeit device.

[0093] The D City Cloud Control Center generates control commands based on trusted data, signs the commands using a key derived from the geographical factor of "City D, Province C," and sends them to the execution device in Tunnel A. After verifying the validity of the command signature, the execution device performs the corresponding operation.

[0094] The embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A multi-level key distribution method supporting cross-domain interoperability of tunnel electromechanical systems, characterized in that, include: S1 system initialization phase: The Trusted Center generates non-singular elliptic curve parameters, the system master private key, and the system public key, and then publishes the public parameters. The tunnel electromechanical equipment submits hardware identifiers and tunnel identifiers to the tunnel management center in the corresponding area. The tunnel management center forwards the registration information to the trusted center and then verifies and generates a partial private key and traceable device identifier corresponding to the tunnel electromechanical equipment. These are then securely distributed to the tunnel electromechanical equipment through the tunnel management center. S2 multi-level geographical key distribution stage: The tunnel electromechanical equipment combines traceability identifiers, provincial identifiers, municipal identifiers, and tunnel identifiers to construct a dispersion factor; Based on the dispersion factor, partial private key and device-selected private key, a unique session key and authentication key are derived through the national cryptographic hash function to achieve a strong binding between the key and the physical location and management ownership of the device; S3 cross-domain data interoperability phase: The first regional device and the second regional controller use the national cryptographic SM2 algorithm for bidirectional authentication, and independently calculate the same session key based on the negotiated shared key and regional dispersion factor, and use the SM4 algorithm to encrypt communication.

2. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, During the device registration phase, the steps for verifying the validity of a portion of the private key include: Check if the scalar product of the partial private key and the base point is equal to a linear combination of the device public key and the system public key. If it is true, accept it; otherwise, discard it.

3. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, The trusted center randomly selects elliptic curve parameters and a master private key, calculates the system public key, and generates public parameters, which include elliptic curve parameters, the system public key, and a hash function; the hash function... to All are implemented using the national cryptographic SM3 algorithm, and the hash function includes: ， ， ， ， ， in, Indicates the bit length of the negotiation key.

4. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, In the multi-level geographical key distribution stage: The complete private key of a device consists of a partial private key and a self-selected private key, and the corresponding public key is the scalar product of the self-selected private key and the base point. The session key and authentication key are generated by jointly calculating the dispersion factor, a portion of the private key, and a self-selected private key using the national cryptographic SM3 hash function.

5. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, The cross-domain data interoperability phase specifically includes: Device A uses the full private key to perform an SM2 signature on the timestamp and encrypted identity information; b. The controller verifies the validity of the signature by calculating whether the relationship between the signature value and the device public key material holds true. c. Both parties communicate using encrypted encryption based on the derived session key and the SM4 algorithm.

6. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, The Trusted Center or Tunnel Management Center periodically issues key update instructions, and the device generates a new private key and session key; when a device is identified as malicious, the Trusted Center queries its true identity based on the traceable identifier and adds it to the blacklist.

7. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, The elliptic curve is randomly selected from the non-singular curves recommended by the Chinese national cryptographic standard SM2, satisfying the equation y²=x³+ax+bmodp, and the discriminant 4a³+27b²≠0, where... p is a large prime number.

8. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, The tunnel electromechanical equipment includes sensors, actuators, lighting equipment, or fan controllers.

9. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, Key update steps during cross-domain migration of tunnel electromechanical equipment: When the tunnel electromechanical equipment is moved from the first region to the second region, the tunnel management center in the second region initiates a migration authorization request to the trusted center. After the trusted center verifies the device, the hardware identifier and some private keys remain unchanged. Only the associated geographical dispersion factor is updated to the provincial identifier, city identifier and tunnel identifier of the second region. After the tunnel electromechanical equipment is powered on in the second region, it re-derives a new session key based on the new regional dispersion factor and completes authentication and communication with the system in the second region.

10. The multi-level key distribution method for supporting cross-domain interoperability of tunnel electromechanical systems according to claim 1, characterized in that, In the multi-level geographical key distribution step, the formula for the device to derive the session key is: Where H4 is the national cryptographic SM3 hash function, x i A personalized private key that the device chooses itself.

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