Method, device and power system for authenticating edge devices

Abstract

The present invention provides a method, device and power system for authenticating an edge device, and relates to the field of power engineering technology and data encryption. The method includes: obtaining a device private key, a random number and a message to be sent of a first edge device; processing the device private key based on a random function to obtain S-box information related to the first edge device; processing a substitution matrix and an initial message digest of a message to be sent based on a substitution function to obtain a message digest; performing a query operation on a preset inverse cumulative distribution information table based on a random number to obtain a Gaussian sampling value that meets a discrete Gaussian distribution condition, wherein the cumulative distribution value in the inverse cumulative distribution information table is obtained based on a probability mass function processing a preset value, and the preset value is associated with the cumulative distribution value; determining an identity signature based on the message digest, the device private key and the Gaussian sampling value; and sending the identity signature and the message to a service end in the power system.

Description

Technical Field

[0001] The present invention relates to the fields of power engineering technology and data encryption, and more specifically, to a method, device and power system for performing identity authentication on edge devices. Background Art

[0002] With the rapid development of Internet of Things technology, communication networks can be built in power systems based on edge devices such as smart meters, distribution terminals, and sensors to achieve frequent data interaction and communication between edge devices, thereby improving the stability and efficiency of the power system. In order to ensure the communication security between multiple edge devices in the power system, it is necessary to authenticate the edge devices to avoid information leakage and ensure smooth communication between edge devices. However, edge devices have low power consumption and limited computing resources, making it difficult to provide sufficient computing resources to perform device authentication operations. Summary of the invention

[0003] In view of this, the present invention provides a method, an apparatus and a power system for authenticating an edge device.

[0004] One aspect of the present invention provides a method for authenticating an edge device, characterized in that it is applied to a first edge device of an electric power system, and the method includes: obtaining a device private key, a random number and a message to be sent of the first edge device, wherein the device private key is determined based on processing the device identity information of the first edge device by a pseudo-random number generator; processing the device private key based on a random function to obtain S-box information related to the first edge device, wherein the S-box information includes a substitution matrix of the first edge device; processing the substitution matrix and an initial message digest of the message to be sent based on a substitution function to obtain a message digest; performing a query operation on a preset inverse cumulative distribution information table based on the random number of the first edge device to obtain a Gaussian sampling value that meets a discrete Gaussian distribution condition, wherein the cumulative distribution value in the inverse cumulative distribution information table is obtained based on processing a preset value with a probability mass function, and the preset value is associated with the cumulative distribution value; determining an identity signature based on the message digest, the device private key and the Gaussian sampling value; and sending the identity signature and the message to a service end in the electric power system.

[0005] Another aspect of the present invention provides an apparatus for authenticating an edge device, characterized in that the apparatus is applied to a first edge device of an electric power system, and comprises: an acquisition module for acquiring a device private key, a random number and a message to be sent of the first edge device, wherein the device private key is determined based on processing the device identity information of the first edge device by a pseudo-random number generator; a first acquisition module for processing the device private key based on a random function to obtain S-box information related to the first edge device, wherein the S-box information includes a substitution matrix of the first edge device; a message digest acquisition module for processing the device private key based on a substitution function A substitution matrix and an initial message digest of a message to be sent are used to obtain a message digest; a second obtaining module is used to perform a query operation on a preset inverse cumulative distribution information table based on the random number of the first edge device to obtain a Gaussian sampling value that satisfies a discrete Gaussian distribution condition, wherein the cumulative distribution value in the inverse cumulative distribution information table is obtained based on a probability mass function processing a preset value, and the preset value is associated with the cumulative distribution value; an identity signature determination module is used to determine an identity signature based on the message digest, the device private key and the Gaussian sampling value; and a sending module is used to send the identity signature and the message to a service end in the power system.

[0006] Another aspect of the present invention provides an electric power system, characterized in that it includes: a first edge device, including: an apparatus provided according to an embodiment of the present invention; a second edge device, as a service end, communicatively connected to the above-mentioned first edge device.

[0007] According to an embodiment of the present invention, a device private key generated based on device identity information is processed by a random function to obtain S-box information, and dynamic S-box information can be generated based on a lattice cryptographic mechanism, thereby dynamically characterizing the identity information of the first edge device. By processing a substitution matrix and a message through a substitution function to obtain a message digest, and querying a Gaussian sampling value that satisfies a discrete Gaussian distribution condition based on a random number, the first edge device can quickly obtain a Gaussian sampling value by looking up a table, thereby reducing the computational overhead generated by floating-point operations and complex rejection sampling operations in the lattice cryptographic mechanism to determine the Gaussian sampling value, thereby saving the computational overhead of the first edge device signing based on the lattice cryptographic mechanism. In this way, the first edge device can allow the server to perform identity authentication by sending a message and an identity signature, so that the identity authentication operation based on the lattice cryptographic mechanism can be applicable to edge devices with less computing power resources, thereby improving the authentication efficiency and data security of identity authentication for edge devices in the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0009] Figure 1 A diagram showing an application scenario of the method and apparatus for performing identity authentication on edge devices provided by the present invention.

[0010] Figure 2 A flow chart of a method for authenticating an edge device according to an embodiment of the present invention is shown.

[0011] Figure 3 A flow chart for determining a random number according to an embodiment of the present invention is shown.

[0012] Figure 4 A block diagram of an apparatus for performing identity authentication on an edge device according to an embodiment of the present invention is shown.

[0013] Figure 5 A schematic diagram of a power system according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0014] Below, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of concepts of the present invention.

[0015] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0016] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0017] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0018] In the embodiments of the present invention, the collection, updating, analysis, processing, use, transmission, provision, disclosure, storage and other aspects of the data involved (for example, including but not limited to user personal information) are in compliance with the provisions of relevant laws and regulations, are used for legitimate purposes, and do not violate public order and good morals. In particular, necessary measures are taken for user personal information to prevent illegal access to user personal information data and maintain the security of user personal information, network security and national security.

[0019] In the embodiment of the present invention, before obtaining or collecting the user's personal information, the user's authorization or consent is obtained.

[0020] The inventors found that the edge devices in the power system have the characteristics of limited computing power, limited storage space, and strict power consumption requirements, and cannot support traditional cryptographic algorithms that consume large computing resources. At the same time, the rapid development of cryptography effectively cracks encrypted information in the information exchange process, posing a major threat to the cryptographic system. Therefore, in order to ensure the security of communication between edge devices, especially the security of identity authentication of edge devices, it is urgent to design an efficient and secure identity authentication method suitable for edge devices with limited computing power to counter attacks by brute force cracking algorithms such as quantum computers.

[0021] The embodiment of the present invention provides a method, device and power system for authenticating an edge device. The method for authenticating an edge device is applied to a first edge device of the power system, and the method comprises: obtaining a device private key, a random number and a message to be sent of the first edge device, wherein the device private key is determined based on a pseudo-random number generator processing the device identity information of the first edge device; processing the device private key based on a random function to obtain S-box information related to the first edge device, wherein the S-box information includes a substitution matrix of the first edge device; processing the substitution matrix and an initial message digest of the message to be sent based on a substitution function to obtain a message digest; performing a query operation on a preset inverse cumulative distribution information table based on the random number of the first edge device to obtain a Gaussian sampling value that meets a discrete Gaussian distribution condition, wherein the cumulative distribution value in the inverse cumulative distribution information table is obtained based on a probability mass function processing a preset value, and the preset value is associated with the cumulative distribution value; determining an identity signature based on the message digest, the device private key and the Gaussian sampling value; and sending the identity signature and the message to a service end in the power system.

[0022] According to an embodiment of the present invention, a device private key generated based on device identity information is processed by a random function to obtain S-box information, and dynamic S-box information can be generated based on a lattice cryptographic mechanism, thereby dynamically characterizing the identity information of the first edge device. By processing a substitution matrix and a message through a substitution function to obtain a message digest, and querying a Gaussian sampling value that satisfies a discrete Gaussian distribution condition based on a random number, the first edge device can quickly obtain a Gaussian sampling value by looking up a table, thereby reducing the computational overhead generated by floating-point operations and complex rejection sampling operations in the lattice cryptographic mechanism to determine the Gaussian sampling value, thereby saving the computational overhead of the first edge device signing based on the lattice cryptographic mechanism. In this way, the first edge device can allow the server to perform identity authentication by sending a message and an identity signature, so that the identity authentication operation based on the lattice cryptographic mechanism can be applicable to edge devices with less computing power resources, thereby improving the authentication efficiency and data security of identity authentication for edge devices in the power system.

[0023] Figure 1 A diagram showing an application scenario of the method and apparatus for performing identity authentication on edge devices provided by the present invention.

[0024] like Figure 1 As shown, the application scenario 100 according to this embodiment may include a first edge device 101, a station intelligent service terminal 102, a trusted authority terminal 103, and a network 104. The network 104 is used to provide a medium for a communication link between the first edge device 101, the station intelligent service terminal 102, and the trusted authority terminal 103. The network 104 may include various connection types, such as wired, wireless communication links, or optical fiber cables, etc.

[0025] The first edge device 101 and the intelligent service end 102 of the substation area can interact through the network 104 to receive or send messages, etc. The first edge device 101 can be equipped with a processor such as a CPU. The first edge device 101 can be, for example, a smart meter device in a power system, which is used to record user-side power data such as user power consumption information and voltage change information.

[0026] The intelligent service end 102 of the substation area may include an intelligent fusion terminal of the substation area, which may serve as a server to receive messages sent by the first edge device 101, thereby obtaining user-side power data. The intelligent service end 102 of the substation area may also receive information such as an identity signature sent from the first edge device 101 to authenticate the first edge device 101, so as to prevent other devices outside the power system from sending junk information that affects the operation of the power system.

[0027] The trusted authority end 103 is a server that provides various services, for example, a server that provides a device public key and a device private key to the first edge device 101 and the area intelligent service end 102 .

[0028] It should be noted that the method for authenticating an edge device provided in the embodiment of the present invention can generally be executed by the first edge device 101. Accordingly, the apparatus for authenticating an edge device provided in the embodiment of the present invention can generally be arranged in the first edge device 101. The method for authenticating an edge device provided in the embodiment of the present invention can also be executed by an edge device or edge device that is different from the first edge device 101 and can communicate with the area intelligent service terminal 102 and / or the trusted authority terminal 103. Accordingly, the apparatus for authenticating an edge device provided in the embodiment of the present invention can also be arranged in an edge device or edge device cluster that is different from the first edge device 101 and can communicate with the area intelligent service terminal 102 and / or the trusted authority terminal 103.

[0029] It should be understood that Figure 1 The number of edge devices, networks, intelligent service terminals in the station area, and trusted authority terminals is only illustrative. According to the implementation requirements, there can be any number of edge devices, networks, intelligent service terminals in the station area, and trusted authority terminals.

[0030] Figure 2 A flow chart of a method for authenticating an edge device according to an embodiment of the present invention is shown.

[0031] like Figure 2 As shown, the method for authenticating an edge device in this embodiment is applied to a first edge device in a power system, and the method in this embodiment includes operations S210 to S260.

[0032] In operation S210, a device private key, a random number, and a message to be sent of the first edge device are obtained.

[0033] According to an embodiment of the present invention, the first edge device may be an edge device or an end device in the power system. For example, the first edge device may be an end device with limited computing power of computing resources such as a gateway or a smart meter device in the power system.

[0034] According to an embodiment of the present invention, the device private key is determined based on a pseudo-random number generator processing device identity information of the first edge device. The pseudo-random number generator may be an algorithm model constructed based on a pseudo-random number function (PRF).

[0035] In one example, a trusted authority end that is in communication with the first edge device and the server end may process the device identity information based on a pseudo-random number generator to obtain a device private key, so as to reduce the computational overhead of the first edge device.

[0036] According to an embodiment of the present invention, the random number may be generated by the first edge device, and the embodiment of the present invention does not limit the specific method of generating the random number, as long as the random number corresponds to the first edge device. The random number may be data in any format such as a binary number.

[0037] In operation S220, the device private key is processed based on a random function to obtain S-box information related to the first edge device.

[0038] According to an embodiment of the present invention, the random function may include any type of random function such as a pseudo-random function, a verifiable random function (VRF), etc. The embodiment of the present invention does not limit the specific type of the random function.

[0039] According to an embodiment of the present invention, the S-box (Substitution-box) information can be understood as the basic structural data of the encryption algorithm to perform the substitution calculation operation. The S-box information includes the substitution matrix S of the first edge device. ID . Substitution matrix S ID It can be a matrix of dimension n×n, replacing the matrix S ID Each matrix element can be output by a pseudo-random mechanism that processes the device private key through a random function, thereby ensuring that the S-box information of each first edge device is unique and can also change when the same first edge device generates different identity signatures.

[0040] In operation S230, the substitution matrix and the initial message digest of the message to be sent are processed based on the substitution function to obtain a message digest.

[0041] According to an embodiment of the present invention, the substitution function may be a substitution matrix corresponding to the S-box information of the first edge device. The initial message digest may be obtained by processing the message based on a hash algorithm. The message digest may fuse the content of the message to be sent and the information content of the device identity information characterizing the first edge device so that the message digest can correspond to the identity of the first edge device.

[0042] In one example, the initial message digest H M It is obtained by hashing the message M. Using the substitution matrix S of the dynamic S-box information ID The initial message digest H M Perform substitution to obtain the message digest H after substitution Ms The message digest generation process can be expressed based on the following formulas (1) and (2).

[0043] , (1);

[0044] (2);

[0045] Among them, Substitute represents the substitution matrix S ID The corresponding substitution function.

[0046] In operation S240, a query operation is performed on a preset inverse cumulative distribution information table based on the random number of the first edge device to obtain a Gaussian sampling value that meets a discrete Gaussian distribution condition.

[0047] According to an embodiment of the present invention, the preset value is associated with the cumulative distribution value, and the inverse cumulative distribution information table may store the association relationship between the preset value and the cumulative distribution value.

[0048] In one example, a target cumulative distribution value that matches the random number of the first edge device can be determined from the inverse cumulative distribution information table, and a Gaussian sampling value can be determined based on a target preset value corresponding to the target cumulative distribution value. The cumulative distribution value in the inverse cumulative distribution information table is obtained by processing the preset value based on a probability mass function (PMF). The cumulative distribution value can be used to characterize the probability distribution of multiple preset values ​​as discrete random variables so that the Gaussian sampling value can meet the discrete Gaussian distribution condition.

[0049] In one example, the random number may be processed based on a preset query function to obtain the Gaussian sampling value in the inverse cumulative distribution information table.

[0050] In operation S250, an identity signature is determined based on the message digest, the device private key, and the Gaussian sampling value.

[0051] According to an embodiment of the present invention, the message digest, the device private key and the Gaussian sampling value may be processed based on the signature function Sign() of the lattice cryptographic mechanism to obtain the identity signature s.

[0052] In operation S260 , the identity signature and the message are sent to a service end in the power system.

[0053] According to an embodiment of the present invention, the server can process the identity signature through an authentication function (e.g., a verifiable random function) to authenticate whether the first edge device meets the identity authentication condition. If the identity authentication condition is met, the power system data acquisition task or data analysis task can be executed by processing the message.

[0054] In one example, the server can also verify the data integrity of the message based on the identity signature to prevent the message from being tampered with by an untrusted third party and improve information security.

[0055] According to the method provided in the embodiment of the present invention, it is possible to counter quantum algorithm attacks based on the lattice cryptographic mechanism to improve information security. At the same time, the Gaussian sampling operation with high computational complexity in the lattice cryptographic mechanism can be replaced by a query operation based on a random number against the inverse cumulative distribution information table to obtain a Gaussian sampling value that satisfies the Gaussian distribution condition, so as to reduce the computational overhead of the first edge device. In this way, the first edge device can improve its resistance to cryptographic attack algorithms such as differential analysis algorithms and linear analysis algorithms based on a nonlinear substitution mechanism of dynamic S-box information under the condition of limited computing resources, thereby enhancing the security of identity authentication.

[0056] According to an embodiment of the present invention, the first edge device may be an end device in the power system, and the service end may be an edge device in the power system.

[0057] In one example, the first edge device includes a smart meter device, and the service end includes a smart fusion terminal for a substation. It should be noted that in the embodiment of the present invention, the smart meter device is used as the first edge device, and the substation smart fusion terminal is used as the service end to explain the method provided by the embodiment of the present invention in detail, and it is not used to limit the method provided by the embodiment of the present invention to be only used for smart meter devices or substation smart fusion terminals.

[0058] According to an embodiment of the present invention, the device private key is determined by the trusted authority performing the following operations: determining the master key and the master public key based on the set integer lattice parameters and discrete Gaussian distribution parameters; and obtaining the device private key based on the pseudo-random number generator processing the master key and the identity hash value of the first edge device.

[0059] According to an embodiment of the present invention, a trusted authority, or a trusted key generation center (KGC), can be used to generate and distribute device private keys and device public keys to ensure that information is not leaked between the first edge device and the server. It is understandable that different first edge devices have different device private keys, and the device private keys correspond to the device identity information of the first edge device.

[0060] According to an embodiment of the present invention, the trusted authority can set system parameters for the edge devices of the power system, such as selecting an appropriate security level according to the power system requirements, setting the security parameter λ, setting the integer lattice parameter n for the lattice cryptographic mechanism, and setting the large prime modulus q. Setting the discrete Gaussian distribution parameter σ∈Z + , the discrete Gaussian distribution parameter σ is used to control the standard deviation of discrete Gaussian sampling. At the same time, the hash function is defined , used to hash identity information.

[0061] According to an embodiment of the present invention, the trusted authority can set a hash function H to map the user's device identity information ID to a fixed-length hash value, thereby obtaining an identity hash value H ID =H(ID). Identity hash value H ID It is used to ensure the uniqueness and security of device identity information. The device identity information ID is an identifier of any length, and H can be a lightweight secure hash function SipHash.

[0062] According to an embodiment of the present invention, the trusted authority generates a master key MSK and a master public key h by processing a security parameter λ, an integer lattice parameter n, a large prime modulus q, and a discrete Gaussian distribution parameter σ. For example, the master key MSK and the master public key h may be generated based on the following formula (3).

[0063] (3);

[0064] Among them, Setup represents the key generation algorithm used for system initialization.

[0065] According to an embodiment of the present invention, the trusted authority uses a pseudo-random number generator (PRF) to combine a sufficiently large random integer master key MSK and an identity hash value H ID Generate a device private key. For example, the device private key sk can be expressed based on the following formula (4): ID .

[0066] (4);

[0067] Among them, PRF represents a secure pseudo-random number generator, and MSK is the master key, which is not public and is only used to generate the device private key. The pseudo-random number generator processes the master key and identity hash value, and the output device private key is a random and unpredictable value. Even if the attacker knows part of the input of the pseudo-random number generator, it is still impossible to effectively infer the device private key, thereby ensuring the security of the device private key. The pseudo-random number generator is designed to be unpredictable, so that even if the attacker obtains part of the master key and identity hash value data, or also obtains the output data (device private key), it is still impossible to reverse the master key of the pseudo-random number generator. Improve the strong anti-collision and anti-analysis capabilities of the device private key.

[0068] In one example, the pseudo-random number generator is constructed based on a pseudo-random function of HMAC (Hash-based Message Authentication Code). For example, the device private key sk can be calculated based on the following formula (5): ID .

[0069] (5);

[0070] Among them, HMAC() represents a pseudo-random function based on the HMAC mechanism. The device private key sk output by HMAC() ID A pseudo-random value of fixed length.

[0071] According to an embodiment of the present invention, obtaining a device private key based on processing a master key and an identity hash value of a first edge device using a pseudo-random number generator includes: performing an XOR operation on the master key and a preset internal filling constant to obtain initial internal data; performing a hash operation on the initial internal data and the identity hash value to obtain internal data; performing an XOR operation on the master key and a preset external filling constant to obtain initial external data; and performing a hash operation on the initial external data and the internal data to obtain the device private key.

[0072] According to an embodiment of the present invention, the device private key sk can be determined based on the following formula (6): ID .

[0073] (6);

[0074] Where H( ) represents a hash function (e.g. SipHash), ipad is an internal padding constant, and opad is an external padding constant. Represents the exclusive-or operation.

[0075] According to an embodiment of the present invention, performing an XOR operation on a master key and a preset internal filling constant to obtain initial internal data; and performing a hash operation on the initial internal data and an identity hash value to obtain internal data may include performing an internal hash operation based on the following formula (7) to obtain the initial internal data.

[0076] (7);

[0077] The master key MSK is XORed with the internal padding constant ipad to obtain the initial internal data, and then the initial internal data is XORed with the identity hash value H ID Connect, and then perform the first hash operation on the connected data through the hash function H() to obtain the internal data inner.

[0078] According to an embodiment of the present invention, performing an XOR operation on a master key and a preset external padding constant to obtain initial external data; and performing a hash operation on the initial external data and internal data to obtain a device private key may include performing an external hash operation based on the following formula (8) to obtain the device private key.

[0079] (8);

[0080] The master key MSK is XORed with the external padding constant opad to obtain the initial external data, which is then concatenated with the internal data inner, and then a second hash operation is performed to obtain a pseudo-random value as the device private key sk. ID .

[0081] Figure 3 A flow chart for determining a random number according to an embodiment of the present invention is shown.

[0082] like Figure 3 As shown, in this embodiment, the random number is determined based on operations S310 to S330.

[0083] In operation S310, a white noise signal generated by a noise generating component of a first edge device is acquired.

[0084] In operation S320, the white noise signal is compared with a preset reference voltage to obtain a random bit signal.

[0085] In operation S330, a random number is determined based on the random bit signal.

[0086] According to an embodiment of the present invention, operations S310 to S330 may be performed based on the first edge device.

[0087] According to an embodiment of the present invention, the noise generating component may include a component in the first edge device that can generate a white noise signal. The noise generating component may be, for example, a hardware circuit such as a noise diode to simulate a white noise signal.

[0088] According to an embodiment of the present invention, a white noise signal is a random signal with a constant power density at all frequencies. By simulating the white noise signal through hardware circuits such as a noise diode inside a first edge device with limited computing power, the difficulty of random number collection due to complex floating-point operations and rejection sampling mechanisms during the random number sampling process can be avoided, and a one-to-one correspondence between the random number and the first edge device can be achieved, thereby increasing the difficulty of cracking the random number.

[0089] According to an embodiment of the present invention, a white noise signal can be compared with a reference voltage based on a comparator circuit of a first edge device. The reference voltage may include a zero voltage, and when the white noise signal is higher than the reference voltage, a logic high level signal 1 is output; when the white noise signal is lower than the reference voltage, a logic low level signal 0 is output. A random bit stream can be obtained by sampling the logic high level signal 1 and / or the logic low level signal 0 output by the comparator circuit based on a preset sampling rate, and the random bit stream is determined as a random bit signal. Since the amplitude of the white noise signal randomly changes in the positive and negative interval based on the reference voltage, the random bit stream generated by the white noise signal is similar to an independent and identically distributed uniform random bit.

[0090] According to an embodiment of the present invention, determining a random number based on a random bit signal may include: grouping the collected random bit signals according to a preset length (eg, 8 bits), and each group of binary random bit strings obtained may be used as a random number.

[0091] In one example, each set of binary random bit strings can be converted into corresponding decimal integers to obtain a uniform distribution between 0 and 2. n A random number in the range −1, where n is the length of the bit group. It will be uniformly distributed between 0 and 2 n A random number in the range of −1 is used as the random number of the first edge device.

[0092] According to an embodiment of the present invention, the preset value includes a preset integer value, and the inverse cumulative distribution information table is determined based on the following operations: processing multiple preset integer values ​​based on a probability mass function to obtain initial probability values ​​corresponding to each of the multiple preset integer values; processing the initial probability values ​​corresponding to each of the multiple preset integer values ​​based on a cumulative distribution function to obtain initial cumulative distribution values ​​corresponding to each of the multiple preset integer values; quantizing the initial cumulative distribution values ​​to obtain cumulative distribution values; and constructing the inverse cumulative distribution information table based on the cumulative distribution values ​​corresponding to each of the multiple preset integer values.

[0093] According to an embodiment of the present invention, a preset integer value is processed based on a probability mass function (PMF), which can be expressed as the following formula (9).

[0094] (9);

[0095] Wherein, σ is the standard deviation, Z is the normalization constant, and the normalization constant Z is used to make the sum of the initial probability values ​​corresponding to all preset integer values ​​equal to 1. P(x) represents the initial probability value, x is the preset integer value, and P() represents the probability mass function.

[0096] According to an embodiment of the present invention, initial probability values ​​corresponding to preset integer values ​​are processed based on a cumulative distribution function to obtain initial cumulative distribution values ​​corresponding to each of a plurality of preset integer values, which can be expressed based on the following formula (10).

[0097] (10);

[0098] Wherein, CDF() is the Cumulative Distribution Function (CDF), k represents the lower limit of the integer value range, and x represents the preset integer value of the currently executed operation. CDF(x) is the initial cumulative distribution value corresponding to the preset integer value x, and CDF(x) can represent the accumulation of initial probability values ​​from the lower limit of the integer value range to the preset integer value of the currently executed operation.

[0099] According to an embodiment of the present invention, in order to facilitate subsequent table lookup operations, the initial cumulative distribution value can be quantized to obtain the cumulative distribution value: the initial cumulative distribution value corresponding to the preset integer value is mapped to an integer range (for example, an integer range of 0 to 255) to obtain the cumulative distribution value (or simply referred to as CDF value in the embodiment of the present invention). In order to facilitate subsequent table lookup operations. The initial cumulative distribution value can be processed based on a quantization function, and the initial cumulative distribution value is multiplied by 2 n −1 and rounded to get the cumulative distribution value, where n is the bit length of the random number.

[0100] According to an embodiment of the present invention, constructing an inverse cumulative distribution information table based on the cumulative distribution values ​​corresponding to each of a plurality of preset integer values ​​may include using the cumulative distribution value as an index to associate the corresponding preset integer value, thereby constructing an inverse cumulative distribution information table capable of associating and storing the preset integer value x and the cumulative distribution value.

[0101] In one example, in order to optimize storage: due to the computing power and storage resource limitations of the first edge device, the inverse cumulative distribution information table may only store the preset integer value x and the key threshold points in the cumulative distribution value, such as the cumulative distribution value that has changed in multiple cumulative distribution values, and the size of the inverse cumulative distribution information table. For example, the inverse cumulative distribution information table may be represented based on Appendix 1.

[0102] Table 1

[0103]

[0104] In one example, the cumulative distribution value in the inverse cumulative distribution information table can be a uniform random integer ranging from 0 to 255, and the cumulative distribution value is used as the index value of the inverse cumulative distribution table. Since the cumulative distribution value is monotonically non-decreasing, a binary search method is used to accelerate the search for a preset integer value that matches the random number. The queried target preset integer value x is used as a Gaussian sampling value that meets the discrete Gaussian distribution condition.

[0105] Table 2

[0106]

[0107] Among them, cdf quantized() indicates that a quantization operation is performed on the initial cumulative distribution value corresponding to the preset integer value x. By obtaining the random number r of the first edge device, the target preset integer value x matching the random number r can be determined by querying Table 2 as a Gaussian sampling value that conforms to the discrete Gaussian distribution. Among them, the Gaussian sampling value can be queried using the random number r by formula (11).

[0108] (11);

[0109] Among them, GaussSample represents the Gaussian sampling value, Indicates querying the inverse cumulative distribution information table based on the random number r.

[0110] According to an embodiment of the present invention, quantizing the initial cumulative distribution value to obtain the cumulative distribution value may include: mapping the initial cumulative distribution value to a preset integer interval based on a quantization function to obtain an intermediate cumulative distribution value; performing a subtraction operation on two adjacent intermediate cumulative distribution values ​​to obtain a cumulative distribution value corresponding to the preset integer value.

[0111] According to an embodiment of the present invention, the intermediate cumulative distribution values ​​include multiple intermediate cumulative distribution values, and the multiple intermediate cumulative distribution values ​​are arranged in a preset order. It can be understood that the quantized cumulative distribution values ​​can be arranged as intermediate cumulative distribution values.

[0112] According to an embodiment of the present invention, the preset integer interval is determined based on the data length of the random number processed by the power function. For example, it can be based on the function 2 n -1 specifies an integer between 0 and 255.

[0113] According to an embodiment of the present invention, by performing a subtraction operation on two adjacent intermediate cumulative distribution values, the storage space occupied by the obtained cumulative distribution value can be made smaller than the intermediate cumulative distribution value obtained after quantizing the initial cumulative distribution value. In this way, the changes between adjacent intermediate cumulative distribution values ​​in the inverse cumulative distribution table can be stored by differential coding, and the cumulative distribution values ​​are stored based on the differential coding method, which can reduce the storage space occupied by the first edge device.

[0114] In one example, the cumulative distribution value may be expressed based on the following formula (12).

[0115] (12);

[0116] Among them, CDF[i] and CDF[i-1] represent the difference between adjacent intermediate cumulative distribution values ​​in the storage table, and ∆CDF[i] represents the cumulative distribution value corresponding to the i-th preset integer value.

[0117] According to an embodiment of the present invention, obtaining S-box information related to the first edge device based on the random function processing device private key may include: obtaining the substitution matrix and identity verification parameters of the first edge device based on the verifiable random function processing device private key and the identity hash value.

[0118] According to an embodiment of the present invention, the S-box information also includes identity verification parameters, and the first edge device sends the identity verification parameters to the server.

[0119] According to an embodiment of the present invention, the trusted authority can generate S-box information based on the following formula (13).

[0120] (13);

[0121] Among them, (S ID , σ ID ) represents the S-box information, and VRF() represents the verifiable random function. σ ID It is an identity proof parameter, which is used to prove the identity information of the signer (first edge device) to the server.

[0122] In one example, the first edge device signs based on a grid password using the device private key sk ID , the message digest after substitution H Ms The Gaussian sampling value GaussSample is signed to generate the final identity signature s. The operation of generating the identity signature s can be expressed based on formula (14).

[0123] s=Sign(sk ID ,h,H Ms ,GaussSample)∈Z q (14);

[0124] Among them, Sign() is a signature function based on lattice cryptography, h is the device public key, s is the generated identity signature, H Ms The information sent by the first edge device to the server includes the message M to be sent, the identity signature s and the identity verification parameter σ ID .

[0125] According to an embodiment of the present invention, the server uses a random function to process identity authentication parameters, an identity hash value, and a device public key corresponding to a device private key to obtain an identity authentication result. The device public key may be obtained from a trusted authority.

[0126] In an example, the server may perform identity signature verification based on the following formula (15) to implement identity authentication of the first edge device.

[0127] (15);

[0128] Among them, pk ID The device public key of the first edge device can be sent by a trusted authority to the server. It should be understood that the device public key and the device private key can correspond to each other, and the device public key and the device private key can be determined based on a preset key generation algorithm, which will not be described in detail in the embodiments of the present invention. VRF Indicates the operation steps of the server using a verifiable random function to authenticate the first edge device. The authentication result may include true if the authentication is passed and false if the authentication is not passed.

[0129] In an example, the server may also verify the message integrity of the first edge device based on the following formula (16).

[0130] (16);

[0131] Among them, when valid is a true Boolean value, it means that the message integrity verification has passed. When valid is a false Boolean value, it means that the message integrity verification has not passed and the message can be rejected. CVP() represents the Closest Vector Problem (CVP) based on the lattice cryptographic mechanism to process the device public key pk ID , message M, master public key h and signature s to perform operations to verify the legitimacy of the signature.

[0132] In an example, a trusted authority can construct public parameters params=(q,n,H,PRF,"CDF"), including a hash function H, a pseudo-random function PRF, and an inverse cumulative distribution information table "CDF" that satisfies discrete Gaussian distribution conditions, and share the public parameters params with edge devices in the power system to facilitate signature verification by the edge devices in the power system.

[0133] According to the method provided by the embodiment of the present invention, it is possible to avoid relying on a large amount of key management and certificate transmission, and frequently access the certificate authority for identity verification, reduce the computing overhead consumption of edge devices with limited computing power, improve the deployment efficiency of the identity authentication method in the edge devices of the power system, improve the rapid identity authentication between edge devices in the power system, and reduce the communication burden and communication delay. At the same time, based on the lattice cryptographic encryption mechanism to resist information attacks from attackers such as quantum computers, improve the completeness of identity authentication, and generate an anti-cumulative distribution information table through a trusted authority to optimize the floating point calculations and complex rejection sampling processes required for the discrete Gaussian sampling process of the lattice cryptography for identity signing, thereby reducing the computing overhead generated by the edge device in the process of executing the lattice cryptographic signature, reducing the power consumption level of terminal devices such as smart meter devices, and reducing the storage space occupied.

[0134] According to the method provided by the embodiment of the present invention, the complexity and randomness of the identity authentication process are increased by generating a substitution matrix of dynamic S-box information corresponding to the device identity information, thereby improving the resistance to cryptographic attacks such as differential analysis and linear analysis.

[0135] Figure 4 A block diagram of an apparatus for performing identity authentication on an edge device according to an embodiment of the present invention is shown.

[0136] like Figure 4 As shown, the device 400 for authenticating an edge device is applied to the first edge device of the power system, and the device 400 for authenticating an edge device includes an acquisition module 410, a first acquisition module 420, a message digest acquisition module 430, a second acquisition module 440, an identity signature determination module 450 and a sending module 460.

[0137] The acquisition module 410 is used to obtain a device private key, a random number and a message to be sent of the first edge device, wherein the device private key is determined based on a pseudo-random number generator processing device identity information of the first edge device.

[0138] The first obtaining module 420 is used to process the device private key based on a random function to obtain S-box information related to the first edge device, where the S-box information includes a substitution matrix of the first edge device.

[0139] The message digest obtaining module 430 is used to process the substitution matrix and the initial message digest of the message to be sent based on the substitution function to obtain the message digest.

[0140] The second acquisition module 440 is used to perform a query operation on a preset inverse cumulative distribution information table based on the random number of the first edge device to obtain a Gaussian sampling value that meets the discrete Gaussian distribution conditions, wherein the cumulative distribution value in the inverse cumulative distribution information table is obtained based on a probability mass function processing preset value, and the preset value is associated with the cumulative distribution value.

[0141] The identity signature determination module 450 is used to determine the identity signature based on the message digest, the device private key and the Gaussian sampling value.

[0142] The sending module 460 is used to send the identity signature and the message to the service end in the power system.

[0143] According to an embodiment of the present invention, a random number is determined based on the following method: obtaining a white noise signal generated by a noise generating component of a first edge device; comparing the white noise signal with a preset reference voltage to obtain a random bit signal; and determining a random number based on the random bit signal.

[0144] According to an embodiment of the present invention, the preset value includes a preset integer value, and the inverse cumulative distribution information table is determined based on the following operations: processing multiple preset integer values ​​based on a probability mass function to obtain initial probability values ​​corresponding to each of the multiple preset integer values; processing the initial probability values ​​corresponding to each of the multiple preset integer values ​​based on a cumulative distribution function to obtain initial cumulative distribution values ​​corresponding to each of the multiple preset integer values; quantizing the initial cumulative distribution values ​​to obtain cumulative distribution values; and constructing the inverse cumulative distribution information table based on the cumulative distribution values ​​corresponding to each of the multiple preset integer values.

[0145] According to an embodiment of the present invention, the initial cumulative distribution value is quantized to obtain the cumulative distribution value, which includes: based on a quantization function, mapping the initial cumulative distribution value to a preset integer interval to obtain an intermediate cumulative distribution value, wherein the intermediate cumulative distribution value includes multiple intermediate cumulative distribution values, the multiple intermediate cumulative distribution values ​​are arranged in a preset order, and the preset integer interval is determined based on the data length of the random number processed by the power function; performing a subtraction operation on two adjacent intermediate cumulative distribution values ​​to obtain a cumulative distribution value corresponding to the preset integer value.

[0146] According to an embodiment of the present invention, the device private key is determined by the trusted authority performing the following operations: determining the master key and the master public key based on the set integer lattice parameters and discrete Gaussian distribution parameters; and obtaining the device private key based on the pseudo-random number generator processing the master key and the identity hash value of the first edge device.

[0147] According to an embodiment of the present invention, obtaining a device private key based on processing a master key and an identity hash value of a first edge device using a pseudo-random number generator includes: performing an XOR operation on the master key and a preset internal filling constant to obtain initial internal data; performing a hash operation on the initial internal data and the identity hash value to obtain internal data; performing an XOR operation on the master key and a preset external filling constant to obtain initial external data; and performing a hash operation on the initial external data and the internal data to obtain the device private key.

[0148] According to an embodiment of the present invention, the first obtaining module 420 includes a first obtaining unit.

[0149] The first acquisition unit is used to process the device private key and the identity hash value based on a verifiable random function to obtain a substitution matrix and identity verification parameters of the first edge device. The S-box information also includes the identity verification parameters. The first edge device sends the identity verification parameters to the server. The identity hash value is determined by performing a hash operation on the device identity information. The server uses a random function to process the identity verification parameters, the identity hash value and the device public key corresponding to the device private key to obtain an identity authentication result. The device public key is obtained from a trusted authority.

[0150] According to an embodiment of the present invention, the first edge device includes a smart meter device, and the service end includes a substation intelligent fusion terminal.

[0151] According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits, or at least part of the functions of any one of them can be implemented in one module. According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits can be split into multiple modules for implementation. According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits can be at least partially implemented as hardware circuits, such as field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), systems on chips, systems on substrates, systems on packages, application specific integrated circuits (ASICs), or can be implemented by hardware or firmware in any other reasonable way of integrating or packaging the circuit, or by any one of the three implementation methods of software, hardware, and firmware, or by a proper combination of any of them. Alternatively, according to the embodiments of the present invention, one or more of the modules, submodules, units, and subunits can be at least partially implemented as computer program modules, and when the computer program modules are run, the corresponding functions can be executed.

[0152] For example, any multiple of the acquisition module 410, the first acquisition module 420, the message digest acquisition module 430, the second acquisition module 440, the identity signature determination module 450, and the sending module 460 can be combined in one module / unit / sub-unit for implementation, or any one of the modules / units / sub-units can be split into multiple modules / units / sub-units. Alternatively, at least part of the functions of one or more of these modules / units / sub-units can be combined with at least part of the functions of other modules / units / sub-units and implemented in one module / unit / sub-unit. According to an embodiment of the present invention, at least one of the acquisition module 410, the first acquisition module 420, the message digest acquisition module 430, the second acquisition module 440, the identity signature determination module 450 and the sending module 460 can be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), a system on a chip, a system on a substrate, a system on a package, an application-specific integrated circuit (ASIC), or can be implemented by hardware or firmware such as any other reasonable way of integrating or packaging the circuit, or by any one of the three implementation methods of software, hardware and firmware or by an appropriate combination of any of them. Alternatively, at least one of the acquisition module 410, the first acquisition module 420, the message digest acquisition module 430, the second acquisition module 440, the identity signature determination module 450 and the sending module 460 can be at least partially implemented as a computer program module, and when the computer program module is run, the corresponding function can be executed.

[0153] It should be noted that the device part for authenticating the edge device in the embodiment of the present invention corresponds to the method part for authenticating the edge device in the embodiment of the present invention. The description of the device part for authenticating the edge device specifically refers to the method part for authenticating the edge device, which will not be repeated here.

[0154] An embodiment of the present invention further provides a power system. The power system in this embodiment includes: a first edge device and a second edge device.

[0155] The first edge device includes an apparatus for performing identity authentication on the edge device provided according to an embodiment of the present invention.

[0156] The second edge device is connected to the first edge device as a server and can perform identity authentication on the message and identity signature sent by the first edge device.

[0157] Figure 5 A schematic diagram of a power system according to an embodiment of the present invention is shown.

[0158] like Figure 5As shown, the power system 500 of this embodiment includes a trusted authority end 501, a smart meter device 502 as a first edge device, and a substation intelligent fusion terminal 503 as a second edge device. The trusted authority end 501 can send public parameters such as a device private key and an inverse cumulative distribution information table to the smart meter device 502, and send data such as a device public key used to authenticate the smart meter device 502 to the substation intelligent fusion terminal 503.

[0159] The smart meter device 502 generates an identity signature based on the apparatus for authenticating the edge device provided by the embodiment of the present invention, and sends the identity signature, identity proof parameters and message to the substation smart fusion terminal 503. The substation smart fusion terminal 503 processes the identity signature, identity proof parameters and message based on a verifiable random function to perform identity authentication and obtain an identity authentication result.

[0160] It should be noted that Figure 5 The power system shown in is only for illustration, and the embodiments of the present invention do not limit the number of smart meter devices and area smart fusion terminals.

[0161] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions. It can be understood by those skilled in the art that the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways, even if such a combination or combination is not explicitly recorded in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways. All these combinations and / or combinations fall within the scope of the present invention.

[0162] The embodiments of the present invention are described above. However, these embodiments are only for the purpose of illustration, and are not intended to limit the scope of the present invention. Although each embodiment is described above, it does not mean that the measures in each embodiment cannot be used in combination advantageously. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A method for authenticating an edge device, characterized in that: Applied to a first edge device of an electric power system, the method comprises: Obtaining a device private key, a random number, and a message to be sent of the first edge device, wherein the device private key is determined based on a pseudo-random number generator processing device identity information of the first edge device; Processing the device private key based on a random function to obtain S-box information related to the first edge device, wherein the S-box information includes a substitution matrix of the first edge device; Processing the substitution matrix and an initial message digest of the message to be sent based on the substitution function to obtain a message digest; Performing a query operation on a preset inverse cumulative distribution information table based on the random number of the first edge device to obtain a Gaussian sampling value that satisfies a discrete Gaussian distribution condition, wherein the cumulative distribution value in the inverse cumulative distribution information table is obtained by processing a preset value based on a probability mass function, and the preset value is associated with the cumulative distribution value; Determining an identity signature based on the message digest, the device private key, and the Gaussian sampling value; and Sending the identity signature and the message to a service end in the power system; The preset value includes a preset integer value, and the inverse cumulative distribution information table is determined based on the following operations: Processing the plurality of preset integer values ​​based on the probability mass function to obtain initial probability values ​​corresponding to the plurality of preset integer values; Processing the initial probability values ​​corresponding to each of the plurality of preset integer values ​​based on a cumulative distribution function to obtain initial cumulative distribution values ​​corresponding to each of the plurality of preset integer values; quantizing the initial cumulative distribution value to obtain the cumulative distribution value; and The inverse cumulative distribution information table is constructed based on the cumulative distribution values ​​corresponding to each of the plurality of preset integer values.

2. The method according to claim 1, characterized in that The random number is determined based on the following method: Acquire a white noise signal generated by a noise generating component of the first edge device; Comparing the white noise signal with a preset reference voltage to obtain a random bit signal; and Based on the random bit signal, the random number is determined.

3. The method according to claim 1, characterized in that in, The initial cumulative distribution value is quantized to obtain the cumulative distribution value, including: Based on a quantization function, the initial cumulative distribution value is mapped to a preset integer interval to obtain an intermediate cumulative distribution value, wherein the intermediate cumulative distribution value includes a plurality of intermediate cumulative distribution values, the plurality of intermediate cumulative distribution values ​​are arranged in a preset order, and the preset integer interval is determined based on a data length of the random number processed by a power function; A subtraction operation is performed on two adjacent intermediate cumulative distribution values ​​to obtain a cumulative distribution value corresponding to the preset integer value.

4. The method according to claim 1, characterized in that: The device private key is determined by the trusted authority performing the following operations: Determine the master key and the master public key based on the set integer lattice parameters and discrete Gaussian distribution parameters; The device private key is obtained by processing the master key and the identity hash value of the first edge device based on the pseudo-random number generator.

5. The method according to claim 4, characterized in that Processing the master key and the identity hash value of the first edge device based on the pseudo-random number generator to obtain the device private key includes: Performing an XOR operation on the master key and a preset internal filling constant to obtain initial internal data; Performing a hash operation on the initial internal data and the identity hash value to obtain internal data; Performing an XOR operation on the master key and a preset external padding constant to obtain initial external data; and A hash operation is performed on the initial external data and the internal data to obtain the device private key.

6. The method according to claim 1, characterized in that Processing the device private key based on a random function to obtain S-box information related to the first edge device includes: Processing the device private key and the identity hash value based on a verifiable random function to obtain a substitution matrix and an identity authentication parameter of the first edge device, wherein the S-box information also includes the identity authentication parameter, and the first edge device sends the identity authentication parameter to the server, wherein the identity hash value is determined by performing a hash operation on the device identity information; The server uses the random function to process the identity authentication parameter, the identity hash value and the device public key corresponding to the device private key to obtain an identity authentication result, and the device public key is obtained from a trusted authority.

7. The method according to claim 1, characterized in that The first edge device includes a smart meter device, and the service end includes an area smart fusion terminal.

8. A device for authenticating an edge device, characterized in that: A first edge device applied to a power system, the device comprising: An acquisition module, used to acquire a device private key, a random number, and a message to be sent of the first edge device, wherein the device private key is determined based on a pseudo-random number generator processing device identity information of the first edge device; A first obtaining module, configured to process the device private key based on a random function to obtain S-box information related to the first edge device, wherein the S-box information includes a substitution matrix of the first edge device; A message digest obtaining module, used for processing the substitution matrix and the initial message digest of the message to be sent based on the substitution function to obtain a message digest; A second obtaining module is used to perform a query operation on a preset inverse cumulative distribution information table based on the random number of the first edge device to obtain a Gaussian sampling value that meets the discrete Gaussian distribution condition, wherein the cumulative distribution value in the inverse cumulative distribution information table is obtained by processing a preset value based on a probability mass function, and the preset value is associated with the cumulative distribution value; an identity signature determination module, configured to determine an identity signature based on the message digest, the device private key, and the Gaussian sampling value; and A sending module, used for sending the identity signature and the message to a service end in the power system; The preset value includes a preset integer value, and the inverse cumulative distribution information table is determined based on the following operations: Processing the plurality of preset integer values ​​based on the probability mass function to obtain initial probability values ​​corresponding to the plurality of preset integer values; Processing the initial probability values ​​corresponding to each of the plurality of preset integer values ​​based on a cumulative distribution function to obtain initial cumulative distribution values ​​corresponding to each of the plurality of preset integer values; quantizing the initial cumulative distribution value to obtain the cumulative distribution value; and The inverse cumulative distribution information table is constructed based on the cumulative distribution values ​​corresponding to each of the plurality of preset integer values.

9. A power system, characterized in that: include: The first edge device includes: The device as claimed in claim 8; The second edge device acts as a server and is connected to communicate with the first edge device.

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