Credible low-altitude perception and data evidence storage platform based on block chain and attribute password

Abstract

The invention provides a credible low-altitude perception and data storage platform based on a block chain and an attribute password, which comprises a user interaction layer, a logic processing layer, a block chain and a storage layer. A server side of a flight identity authentication and authority management module, a server side of a flight state perception and anomaly detection module and a server side of an algorithm support module are established on a server of a user, and a user side of the algorithm support module is established on the server of the user and is responsible for locally storing sensitive privacy data such as an asymmetric secret key, a user private key, an attribute private key and an authorized attribute private key of the user. Key pair generation, attribute creation, attribute authorization, data decryption and other operation support related to privacy data are provided, it is ensured that user data are locally stored and used, and no privacy information is exposed to the outside; according to the invention, a low-altitude flight management infrastructure integrating identity management, flight supervision and data security is constructed.

Description

Technical Field

[0001] This invention belongs to the field of blockchain and cryptography technology, specifically relating to a trusted low-altitude sensing and data storage platform based on blockchain and attribute cryptography. Background Technology

[0002] In recent years, the drone industry has developed rapidly and has been widely applied in various industries. Data from the Civil Aviation Administration of China shows that as of June 2024, there were 1.875 million registered drones nationwide, over 14,000 commercial drone companies, and more than 225,000 drone pilot licenses. From January to June this year, the cumulative flight hours of civilian drones nationwide reached 9.816 million hours, an increase of 134,000 hours compared to the same period last year. The "White Paper on the Development of China's Low-Altitude Economy (2024)" indicates that, according to estimates, the scale of my country's low-altitude economy reached 505.95 billion yuan in 2023, and is expected to exceed the first trillion yuan mark in 2026. The general aviation industry, represented by drones, has become the main engine of the low-altitude economy.

[0003] Against this backdrop, the state strongly supports and guides the development of general aviation, prioritizing the development of the low-altitude economy. The low-altitude economy relies on airspace below 1000 or 3000 meters, involving drones, unmanned aerial vehicles, flying cars, and other aspects, encompassing economic applications in areas such as air commuting, logistics, tourism, and urban management. On March 27, 2024, four departments, including the Ministry of Industry and Information Technology, jointly issued the "Implementation Plan for Innovative Application of General Aviation Equipment (2024-2030)," proposing that by 2030, a new development model for the general aviation industry characterized by high-end, intelligent, and green development will be basically established, general aviation equipment will be fully integrated into all aspects of people's production and life, becoming a powerful driving force for low-altitude economic growth, and forming a trillion-yuan-level market scale for the general aviation industry.

[0004] However, while drones have brought convenience to economic development and social services, the associated management problems have become increasingly prominent. For example, in 2017, Kunming Changshui International Airport and Chengdu Shuangliu Airport experienced multiple incidents of drones disrupting air traffic, leading to flight diversions and passenger delays, severely impacting air transport order. Furthermore, the unauthorized drone flights in Hulunbuir, Inner Mongolia, and the Chengdu Research Base of Giant Panda Breeding in 2024 further fueled public concern about drone safety management. These unauthorized and illegal drone flights violate relevant regulations and pose a serious threat to social order and public safety.

[0005] At the level of laws, regulations, and industry standards, various rules and regulations have been successively introduced in the past two years to improve the rule system. In 2023, the China Aeronautical Integrated Technology Research Institute, DJI Innovations Technology Co., Ltd., and other organizations drafted and formulated the mandatory national standard "Safety Requirements for Civil Unmanned Aerial Vehicle Systems" (GB 42590-2023), which came into effect on June 1, 2024. In addition, mandatory national standards such as "Specifications for Operational Identification of Civil Unmanned Aerial Vehicles" (20241858-Q-417) and "Requirements for Real-Name Registration and Activation of Civil Unmanned Aerial Vehicles" (20241860-Q-417) are currently soliciting opinions. On January 1, 2024, the "Rules for the Safety Management of Civil Unmanned Aerial Vehicle Operations," "Several Provisions on the Production and Management of Civil Unmanned Aerial Vehicles," and "Interim Regulations on the Flight Management of Unmanned Aerial Vehicles" officially came into effect. Meanwhile, the development of the low-altitude economy cannot be separated from the support of basic ground services such as ground communication infrastructure, navigation infrastructure, take-off and landing infrastructure, and meteorological services. Currently, the relevant ground services are all provided by the low-altitude economy operators themselves, which presents certain barriers and has constrained the rapid development of the low-altitude economy.

[0006] 1. China Tower Corporation's distributed base stations

[0007] The tower company owns more than 20,000 towers in Shanghai, with related resources spread throughout the city. They are generally over 25 meters high, with equipment mounting capacity and 5G capabilities on top, and complete power, environmental and fiber optic network resources on the bottom. They are currently high-quality ground communication and navigation infrastructure. Some tower resources have strong load-bearing capacity or rooftops, making them good resource providers for small / micro UAV take-off and landing sites.

[0008] The platform can leverage the nationwide signal base station network of China Tower to build a comprehensive flight data collection and transmission system. China Tower can serve as the core node for ground signal collection and transmission, utilizing its facilities to collect real-time drone operational data, including flight trajectory, speed, and altitude information, and storing this data on the blockchain to ensure its immutability. Based on this, a distributed data sharing network can be formed, enabling real-time data flow across regions and departments.

[0009] 2. Blockchain (Chang'an Chain) Technology

[0010] Blockchain technology is a distributed ledger technology maintained by multiple parties, using cryptography to ensure secure transmission and access, and enabling consistent data storage, tamper-proofing, and non-repudiation. A typical blockchain stores data in a chain structure, combining data blocks sequentially in chronological order. Its core advantage lies in enabling the reliable transfer of information and value in untrusted environments, thus building a reliable collaboration mechanism. Through a series of key technologies such as consensus algorithms, encryption algorithms, peer-to-peer networks, and smart contracts, this technology has demonstrated enormous application potential in numerous fields, including finance, supply chain, government affairs, and judicial evidence preservation.

[0011] Despite the numerous advantages of blockchain technology, existing public blockchains and some consortium blockchains still face some challenges in practical applications. For example, in terms of performance, low transaction throughput and high confirmation latency limit their application in high-frequency scenarios; in terms of privacy protection, there is a conflict between the transparent sharing of on-chain data and the confidentiality requirements of business data; and in terms of usability, the complexity of development and deployment raises the technical threshold.

[0012] To address these challenges, Chang'an Chain, a domestically developed, independent, and controllable consortium blockchain technology aligned with China's national conditions and strategic needs, has emerged. Chang'an Chain boasts high performance, high security, and strong privacy protection. Its modular software architecture allows for flexible selection of different consensus algorithms, encryption algorithms, and other components. In particular, Chang'an Chain has achieved significant improvements in transaction processing performance and incorporates a rich set of privacy-preserving computation contracts, supporting national cryptographic standards and providing robust technical support for building digital economy infrastructure in key areas.

[0013] 3. Attribute cryptography techniques and algorithms

[0014] Attribute-based encryption (ABE) originates from identity-based encryption. The latter associates a public key with the communicator's real-world identity (such as a phone number or address), allowing the sender to calculate the corresponding public key based on that identity. This solves the problem of traditional public-key encryption schemes relying on public-key dictionaries or third-party services for public key transmission. Building on IBE, Sahai and Waters constructed a fuzzy identity-based encryption scheme in 2005, first proposing the concept of ABE. Fuzzy identity-based encryption expands identity into a set of attributes, using these attributes for encryption and decryption. Building on ABE, J. Bethencourt et al. proposed the CP-ABE (Ciphertext-Policy Attribute-Based Encryption) scheme in 2007. CP-ABE associates an access policy with the encrypted plaintext to form ciphertext, and the private key is represented as a set of attributes. CP-ABE borrows from traditional access control methods, setting the access policy as an access control tree composed of AND and OR gates. Decryption can only be successfully executed if the decryptor's attribute set meets the requirements of the access control tree.

[0015] Compared to traditional public-key encryption, ABE offers the following advantages: First, it provides flexible key management. The private key is decoupled from attributes, while the public key is embedded in the ciphertext as an access control policy, eliminating the need for a third-party authority to issue public keys. Second, it supports one-to-many encryption / decryption modes. Traditional public-key encryption operates on a one-to-one basis, using the other party's public key for encryption and one's own private key for decryption, limiting communication to the two parties. Attribute encryption extends this to a one-to-many model, allowing all users meeting access requirements to decrypt without prior communication establishment. Third, it offers fine-grained access policies, achieving fine-grained encryption by adjusting user attribute sets and setting access control structures. Fourth, it resists collusion attacks. Each user's private key is not only related to attributes but also to the master key and a random polynomial, making it impossible for attackers to decrypt plaintext by combining multiple users to create a new private key. Due to these advantages, ABE has significant application value in areas such as third-party cloud storage, log auditing, and targeted broadcast encryption.

[0016] Following the introduction of Access Control Behavior (ABE), researchers began exploring the introduction of hierarchical structures into ABE cryptography. The primary aim was to reduce the computational overhead of traditional ABE while supporting more complex control scenarios. The introduction of hierarchy involves two levels: Bobba R et al. introduced the concept of hierarchy at the attribute level. Considering the complex attribute definitions present in practical CP-ABE product deployments (for example, in the scenario of students granting course access, a student might select different courses from multiple colleges, or even appear simultaneously as both a "student" and a "teaching assistant," leading to redundant, complex, and difficult-to-understand attribute definitions in actual CP-ABE encryption products), they introduced the concept of recursive attribute sets. A user's attribute set is defined as a recursive, hierarchical structure. Wang S et al. introduced the concept of hierarchy at the file level. Their proposed scheme can package multiple plaintexts and multiple access control trees, encrypting and decrypting them unit by unit, using the plaintext set and the new access control tree. This allows for the encryption of multiple plaintexts with different access structures at once, saving storage costs for ciphertexts and access control trees, as well as encryption time costs. Building on this work, Meiyan Xiao et al. proposed the Extendable Hierarchical CP-ABE (EH-CPABE) in 2022, which has a simpler structure.

[0017] To strengthen the effective supervision of drones, reduce the accident rate of aircraft, and improve the development level of the low-altitude economy, this invention, based on the aforementioned background technology, constructs a trusted low-altitude perception and flight data security recording system based on blockchain and attribute cryptography, addressing the following needs in low-altitude economic environment perception and flight management:

[0018] Intelligent identification and flight permission approval for aircraft. The "Interim Regulations on the Flight Management of Unmanned Aerial Vehicles" classify unmanned aerial vehicles (UAVs) into five categories—micro, light, small, medium, and large—based on indicators such as empty weight, maximum flight altitude, and maximum level flight speed. Each category of UAV has different management regulations and flight requirements. Therefore, it is necessary to uniquely identify each aircraft, assign different flight permissions based on its type and function, and dynamically adjust permissions according to specific scenarios to achieve intelligent identity authentication and permission management.

[0019] Real-time flight data collection and analysis. According to the "National Airspace Basic Classification Method," airspace is divided into seven categories, with A, B, C, D, and E being controlled airspace. The "Interim Regulations on the Management of Unmanned Aerial Vehicle Flights" stipulate that unmanned aerial vehicle flight activities are prohibited in controlled airspace without the approval of air traffic management authorities; unmanned aerial vehicles should generally fly separately from manned aircraft. To achieve perception and monitoring of aircraft flight status, real-time collection of aircraft operational data is necessary, combined with their identity information and historical data to automatically detect abnormal behavior and issue early warnings, ensuring the safety of the low-altitude economy.

[0020] Distributed acquisition, secure transmission, and reliable storage of flight data. Given the wide distribution of aircraft, flight data should support distributed acquisition and storage. All data collected and transmitted during flight should be properly and securely processed and stored to ensure it is not leaked, falsified, or tampered with, providing secure and reliable data support for the analysis, review, and accountability of flight behavior. Summary of the Invention

[0021] The purpose of this invention is to provide a trusted low-altitude sensing and data storage platform based on blockchain and attribute cryptography. This invention constructs a multi-layered, modular software platform that leverages the open, transparent, secure, and reliable capabilities of blockchain, combined with the fine-grained access control capabilities and strong privacy protection functions of attribute cryptography, and combined with the distributed site advantages of China Tower Corporation, to achieve trusted low-altitude sensing and secure recording of flight data.

[0022] This invention proposes a trusted low-altitude sensing and data storage platform based on blockchain and attribute cryptography. The platform comprises a user interaction layer, a logic processing layer, and a blockchain and storage layer. The user interaction layer includes a trusted low-altitude sensing and flight data security recording software platform. The logic processing layer includes a flight identity authentication and access control module and a flight status perception and anomaly detection module. The blockchain and storage layer includes a blockchain, an algorithm support module, and IPFS. On the server interacting with the blockchain, a server-side component is built for the flight identity authentication and access control module, the flight status perception and anomaly detection module, and the algorithm support module. On the user's server, a user-side component for the algorithm support module is built. This component is responsible for locally storing sensitive privacy data such as the user's asymmetric private key, user private key, attribute private key, and authorized attribute private key. It provides computational support for privacy-related operations such as key pair generation, attribute creation, attribute authorization, and data decryption, ensuring that user data is stored and used locally without exposing any privacy information.

[0023] (1) The trusted low-altitude perception and flight data security recording software platform connects to the front-end user interface, accepts user registration, aircraft management, and permission management information, and reports flight data information and synchronizes flight data and airspace status information in real time; specifically as follows: (1.1) It provides users with a pre-packaged user operation page, providing a user-friendly interactive experience. The front-end page calls the local user terminal to perform functions such as generating, encrypting, decrypting, and storing sensitive data and keys, and calls the remote server to perform user, UAV, operator management, and full-process tracking management of flight activities; ensuring that users do not need to care about the service deployment architecture, but can use all the capabilities of the system through a unified front-end entry point to complete the trusted low-altitude perception and flight data security recording task; (1.2) It exposes the interface for reporting flight data to the tower company's station nodes, providing data collection, analysis, and storage service capabilities. Two interfaces are exposed to the tower station nodes: one is the reporting interface for flight data actively reported by UAVs, and the other is the recording interface for suspicious flight activity data detected by the monitoring scanning radar on the tower station when scanning the airspace. The former is responsible for receiving, analyzing, organizing, and storing flight activity data actively reported by UAVs during flight and collected and forwarded by tower stations, and issuing alarms for abnormal flight activities. The latter is responsible for receiving and storing data on suspicious flight activities scanned by radars mounted on tower stations, providing reliable records for future analysis, verification, and accountability.

[0024] (2) The Flight Identity Authentication and Access Management module is responsible for the management and identification of entities and related data involved in flight activities, including users, drones, drone operator certificates, and approved flight routes; and is responsible for the declaration, application, and granting of user attributes; using blockchain and cryptography-related technologies, it generates a unique digital identity for the aircraft, performs identity authentication and automatic verification and authorization of flight permits, and sends the request processing results to the trusted low-altitude perception and management software platform, and is responsible for the management and identification of entities and related data involved in flight activities, including users, drones, drone operator certificates, and approved flight routes; and is responsible for the declaration, application, and granting of user attributes; specifically as follows:

[0025] (2.1) After registering, the user registers drone information and registers a drone as their own drone; registers drone operator's license information and binds the user's own drone operator's license; registers approved flight route information and reports the flight route information that the user applied for and was approved by the management agency.

[0026] (2.2) To register drone information, the drone serial number must be provided as the drone’s unique identifier in the real world. Based on this information and other relevant information, the system generates a digital identity identifier that is uniquely bound to the drone based on the national cryptographic SM3 algorithm, which is used for its identity authentication and data association in the system.

[0027] (2.3) To register drone operator certificate information, users must provide a drone operator certificate obtained from the relevant institution. The corresponding "electronic operator certificate" is generated based on the national cryptographic SM3 algorithm as an identifier within the system. Only users with an operator certificate can be approved to fly drones. (2.4) To report flight route information, users must report flight route information approved by the relevant unit to the platform. The system extracts key flight route information to generate a flight token, which serves as the flight certificate in the system. The token ID is generated based on the national cryptographic SM3 algorithm as a unique identifier. The entire process of flight activities is managed based on the flight token.

[0028] (2.5) User Attribute Management; Based on the Decentralized Attribute Cryptography (DABE) algorithm, each user can declare the attributes they manage and request attributes managed by other users. The administrator of the attribute will then authorize the user and generate an authorized attribute private key. Users can then encrypt data using the attribute public key and decrypt the ciphertext using the attribute private key. Only users who satisfy the attribute policy expression specified during encryption can successfully decrypt and obtain the plaintext information.

[0029] (3) The flight status perception and anomaly detection module is responsible for the automated management of the entire process of UAV flight activities, including takeoff, flight, landing, itinerary generation and confirmation. It detects abnormal flight situations in real time and can receive and process suspicious flight activities scanned by radar mounted on the tower site. Flight data is encrypted and stored to ensure privacy; it receives information from a trusted low-altitude perception and flight data security recording software platform, collects the aircraft's operational data in real time, including but not limited to location information, flight speed, heading and environmental monitoring data, etc., and then transmits and analyzes the data, and issues alarms for abnormal behavior; specifically as follows:

[0030] (3.1) Before takeoff, the drone must submit a pre-flight report, providing approved flight route information (flight token), the current user's drone operator's license, and the digital identity of the drone to be used. After the system verifies that the three documents match, the blockchain smart contract automatically executes the clearance and release command, allowing takeoff. Otherwise, takeoff is not permitted. Additionally, an attribute encryption strategy expression and data generated during the flight process are required.

[0031] (3.2) During the flight of the UAV, in accordance with existing UAV management regulations, its current flight status information must be reported in real time. The tower company's site cluster, as a distributed signal receiving node, collects the flight data reported by the UAV and transmits it to the system of this invention by calling the system interface. The system of this invention detects various abnormal behaviors such as flight timeouts, speeding, and exceeding altitude limits, and uses geofencing technology and spatial geometric relationship judgment methods to monitor the preset flight area boundaries (including but not limited to circular, rectangular, and complex polygonal areas) in real time, thereby identifying and warning of abnormal behaviors such as boundary crossings. The platform synchronizes the flight status and issues abnormal behavior alarms to the user's front end in real time through SSE technology. In addition to triggering alarms, abnormal flight behaviors will generate an abnormal activity notification in the system and store it on the blockchain for future accountability.

[0032] (3.3) After the UAV lands, it sends a landing signal, which is received by the tower and transmitted to the system. The system then integrates all flight trajectory data generated during the flight activity and packages it into a flight activity itinerary. The itinerary data is encrypted using the attribute encryption strategy expression specified in step (3.1), and stored after being called by the algorithm support module to ensure that the privacy of the flight records is not leaked, and allows users who meet the policy to access this data in a controlled manner;

[0033] (3.4) Radars are deployed on distributed tower sites to form a high-density airspace detection grid, which scans suspicious flight activities in the airspace in real time and reports them to the platform. The platform stores the suspicious flight activity data on the blockchain for future comparison and investigation.

[0034] (4) Algorithm Support Module: Responsible for integrating the DABE decentralized attribute cryptography algorithm to provide encrypted storage, privacy protection, one-to-many transmission, and fine-grained access control capabilities for flight data. Details are as follows:

[0035] (4.1) User generation; When each user registers on the platform, the attribute password module is called to generate the user's public and private key pair required for the attribute password, as well as the asymmetric encryption public and private key pair used to encrypt the transmission of the authorized attribute private key; the public key is uploaded to the server for public access, and the private key is stored locally on the user's local machine. All use of the private key is performed locally to avoid privacy leakage.

[0036] (4.2) Attribute declaration; Users declare the attributes they manage and generate public and private keys for the attributes; The public key is uploaded to the server, and the private key is stored locally on the user's computer;

[0037] (4.3) Attribute request and grant; User A requests authorization for a certain attribute from User B. User B generates the corresponding authorized attribute private key for User A on the local machine, encrypts it with User A's asymmetric encryption public key, and uploads it to the server. User A can obtain the ciphertext of the authorized attribute private key from the server, and then call the decryption function locally to obtain the authorized attribute private key and save it locally.

[0038] (4.5) Data encryption and decryption; After specifying the attribute strategy expression used for encryption and decryption, the algorithm module uses the public key of the relevant attribute published by the server to encrypt the data, and the ciphertext data is stored on the server; any user can obtain the ciphertext from the server and decrypt it using the authorized attribute private key stored locally; any user who meets the strategy expression can successfully decrypt and obtain the plaintext, realizing one-time encryption of data and decryption by multiple parties, realizing one-to-many data transmission; various attributes can be freely combined in the strategy expression, providing fine-grained data access permission control capabilities.

[0039] In terms of functionality, this invention enables the platform to manage aircraft digital identities in a distributed manner, with the ability to grant, revoke, and verify digital identities; the platform can collect aircraft operational data in real time and process it rapidly; based on smart contracts and attribute cryptography algorithms, it achieves automated management and intelligent rapid approval of flight permits; abnormal behavior detection and early warning, by analyzing aircraft identity information, historical data, and real-time data, automatically detects abnormal behavior and issues early warnings to ensure the security of the low-altitude economy; data is encrypted and transmitted through a blockchain network and stored in distributed nodes of tower base stations to ensure the authenticity and immutability of the data.

[0040] In this invention, the blockchain is designed using the Chang'an Chain solution; tower base stations are used as distributed nodes to enhance monitoring coverage and data collection capabilities, ensuring data integrity and reliability. Smart contracts are used to automate flight permit approval, reducing human intervention and improving approval efficiency; the attribute cryptography scheme employs a decentralized attribute cryptography algorithm (Decentralized ABE, DABE), comprising five algorithms: Global SetUp, Authority SetUp, Encrypt, Key Generate, and Decrypt. The specific process is as follows:

[0041] Algorithm 1: Global Setup:

[0042] Choose an Nth-order bilinear pair: e: G×G→G T Where: G is a subgroup of the group formed by elliptic curves over a finite field; G T It is a multiplicative subgroup of the extended field of a finite field of prime order.

[0043] Where N = p1p2p3, p1p2p3 are three prime numbers, and N is a composite number, representing group G and group G'. T The rank.

[0044] set up It is a subgroup of order p1 of group G, and the group is taken as... The generator g1,

[0045] The common parameters are {e,N,g1}, which are the bilinear pairs, the order of the group, and the generators of the subgroup.

[0046] Additionally, a hash function is needed to map the global identity GID to elements in G: H:{0,1} * →G. This hash function maps any string (represented in 0-1 bit form) to an element in group G. The hash function H should be treated as a random oracle in the process of proving cryptographic security.

[0047] Algorithm 2: Authority Setup:

[0048] In attribute-based encryption It is a ring consisting of addition and multiplication modulo N.

[0049] For each attribute i of the authority, randomly select an element.

[0050] The public key is: The private key is:

[0051] Algorithm 3: Enncyrpt:

[0052] The input to Algorithm 3 Encrypt includes:

[0053] The message to be encrypted, M∈G T ,

[0054] The access control matrix A is an n×l matrix representing the access control matrix in the linear secret-sharing scheme. The attribute mapping ρ is an n-dimensional row vector that maps each row of the matrix to a specific attribute in the access control policy. The access control matrix A and the attribute mapping ρ together constitute the encryption policy specified during the encryption process.

[0055] The public key corresponding to all attributes in the encryption policy

[0056] The calculation process of Algorithm 3 Encrypt is as follows:

[0057] Randomly select elements sum vector in Here, element 's' is both the secret in the encryption process and the blinding factor. (Vector) It is an l-dimensional vector, where the first element is the secret 's', and the other elements are randomly generated. (The vector is randomly selected.) in vector It is an l-dimensional vector, where the first element must be 0, and the other elements are randomly generated.

[0058] Calculate the secret share λ x and w x ,in and

[0059] For each row of access control matrix A, A x It is also necessary to randomly select elements.

[0060] The calculation results of Algorithm 3 Encrypt are as follows:

[0061] Calculate the first part of the ciphertext, C0, where C0 = M·e(g1,g1). s ;

[0062] Calculate the second part of the ciphertext C 1,x ,

[0063] Calculate the third part of the ciphertext C 2,x ,

[0064] Calculate the ciphertext, Part 4, C 3x ,

[0065] These four parts together make up the encrypted ciphertext result.

[0066] Algorithm 4: Key Generate:

[0067] For a user with a global identity (GID), when the user requests attribute i, the corresponding authoritative body grants them the user's public key for attribute i. The formula for calculating the user's public key is as follows: Algorithm 5: Decrypt:

[0068] Algorithm 5, Decrypt, takes as input the ciphertext (i.e., the output of Algorithm 3) and the key (i.e., the output of Algorithm 4). First, based on the second part of the ciphertext, C... 1,x Part C 2,x Part Four C 3x and user public key K i,GID ,calculate:

[0069]

[0070] Next, we need to calculate a set of constants. Satisfying ∑ x c x ·A x = (1,0,…,0). According to the principle of linear secret sharing strategy, such a constant can always be found if the decryption party meets the decryption conditions.

[0071] calculate Calculate M = C0 / e(g1, g1) s M is the decrypted message, which is also the output of Algorithm 5.

[0072] Overall, compared to traditional public-key encryption schemes, attribute-based encryption schemes offer advantages such as one-to-many encryption / decryption modes, flexible key management, and fine-grained access control, addressing the inflexibility of traditional public-key encryption in multi-party encryption scenarios. Furthermore, introducing hierarchical structures at both the attribute and file levels expands application scenarios beyond standard attribute encryption while improving encryption and decryption efficiency.

[0073] The trusted low-altitude sensing and flight data security recording system provided by this invention, based on blockchain technology and attribute cryptography algorithms, deeply integrates the distributed site resources of China Tower Corporation to construct a low-altitude flight management infrastructure that integrates identity management, flight supervision, and data security. Compared with the existing decentralized management methods that rely on manual coordination among multiple departments and are riddled with data silos, the advantages of this invention are:

[0074] (1) A decentralized one-stop collaborative governance architecture has been built, which greatly improves management efficiency.

[0075] This invention utilizes blockchain and smart contracts to program and code decentralized management rules and processes, enabling automated collaboration and trusted data sharing across departments. This fundamentally solves the problems of fragmented authority and responsibility, high communication costs, and long approval cycles in the current management model, providing a unified and efficient management window for low-altitude flight activities.

[0076] (2) It has achieved automated monitoring and three-dimensional reliable perception of the entire flight activity process.

[0077] The system seamlessly integrates flight planning, identity authentication, airspace authorization, real-time monitoring, anomaly alerts, and post-landing data archiving, forming a complete automated management closed loop. Simultaneously, utilizing a wide-area monitoring network comprised of distributed tower sites, combined with both active radar scanning and drone-initiated reporting, it achieves full-process tracking of compliant flight activities and precise detection and comprehensive evidence collection of abnormal activities such as "black flights" and "reckless flights," providing an immutable on-chain evidence chain for post-event accountability.

[0078] (3) While ensuring data privacy, it has achieved secure data sharing and controlled use.

[0079] This invention innovatively combines attribute cryptography algorithms with blockchain, overcoming the inherent contradiction between flight data privacy protection and regulatory auditing. Sensitive flight data is encrypted and stored on the blockchain for verification, and only authorized parties meeting preset attribute policies can decrypt and access it. This mechanism ensures both high data availability and secure sharing capabilities, while providing fine-grained access control far exceeding traditional permission systems, achieving a privacy protection effect of "data available but not visible."

[0080] (4) Deep integration with national key infrastructure ensures the reliability and authority of the system.

[0081] By deploying the system's core nodes at the widely distributed physical sites of the China Tower Corporation, not only has the coverage and data acquisition capabilities of low-altitude signals been greatly enhanced, but the inherent power, network, and security guarantees have also been utilized to ensure the high reliability and credibility of the system services, laying a solid technical foundation for building a national-level low-altitude economic infrastructure. Attached Figure Description

[0082] Figure 1 This is a design diagram of the reliable low-altitude sensing and flight data security recording system of the present invention.

[0083] Figure 2 This is a flowchart illustrating the entire flight data flow in the system of this invention.

[0084] Figure 3 This is a diagram illustrating the architecture of the trusted low-altitude sensing and flight data security recording system of the present invention.

[0085] Figure 4 This is a flight management timing diagram for the present invention.

[0086] Figure 5 This is a timing diagram of the Decentralized Attribute Cryptography (DABE) of the present invention. Detailed Implementation

[0087] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0088] Example 1:

[0089] This system can be divided into the user end of the algorithm support module, the server end of the algorithm support module, the flight identity authentication and permission management module, the flight status perception and anomaly detection module, and the blockchain.

[0090] The client-side and server-side of the algorithm support module are the two core cryptographic modules, forming a complete cryptographic logical chain. DABE is a decentralized attribute-based encryption, and privacy-sensitive functions such as user key management and ciphertext decryption need to be performed on the client-side of the algorithm support module. Specifically, the client-side of the algorithm support module is mainly responsible for privacy-sensitive functions such as key pair generation, private key storage, attribute authorization key generation, and ciphertext decryption, while the server-side of the algorithm support module is responsible for non-privacy-sensitive functions such as the storage and distribution of public parameters, attributes, attribute requests, public keys, and ciphertext.

[0091] The Flight Identity Authentication and Access Management module is responsible for managing users, flight licenses, and drones, storing user information, drone information, and flight license information. User information includes a unique identifier (ID), email address, name, password hash value, flight license, asymmetric encryption public key, attribute user public key, user level, and other drone information. Drone information includes a unique identifier (ID), serial number, specifications, airworthiness level, and the drone's digital ID on the blockchain, and is uniquely bound to one user. Flight license information includes flight license number, name, level, expiration time, and is uniquely bound to one user.

[0092] The flight status perception and anomaly detection module is the core module of UAV flight management. It is responsible for processing flight-related processes, including flight activity application, pre-flight reporting, takeoff report, flight data synchronization, landing report, and itinerary data query.

[0093] (1) During the flight activity application stage, the approval forms obtained by the user from the relevant departments will be stored in the database;

[0094] (2) During the pre-flight reporting stage, the information of the drone and pilot for the flight will be matched with the route requirements, with a focus on whether the airworthiness level, route level and pilot level of the drone match.

[0095] (3) Upon receiving the takeoff report, it will start recording the trip data and listen for subsequent arrival synchronization messages;

[0096] (4) During the real-time flight data synchronization phase, synchronization data will be continuously received. These data have two sources: one is the active reporting during the flight of the UAV, and the other is radar scanning. This flight data will be continuously added to the trip data.

[0097] (5) Receiving a landing report marks the end of the trip; the flight management module will package the trip data and encrypt the data according to the attribute policy specified by the user before takeoff, so that the user can read it.

[0098] Blockchain encompasses blockchains and blockchain interaction tools, allowing the submission of critical business information for notarization. This includes key information related to users, drones, flight licenses, flight tokens, flight activities, and DABE (Data Access and Validation Environment). This critical information includes non-privacy-sensitive details as well as the hash value of the complete data. Furthermore, critical information can be queried from the blockchain, which possesses the characteristics of being immutable and unforgeable.

[0099] One feature of this invention's system is the full-process security management of flight data flow, such as... Figure 2 As shown. The specific description is as follows: (5.1) Data collection phase. The data collected by the system includes two types, both of which are collected and provided by the distributed sites of the China Tower Corporation. One type is the real-time flight data actively reported by UAVs in accordance with regulations, which is received by the distributed sites of the China Tower Corporation and reported to the system; the other type is the data of suspicious flight activities detected by the frequency scanning radar mounted on the China Tower sites when scanning the airspace, which is reported from the China Tower sites to the system.

[0100] (5.2) Data Storage Stage. Upon receiving flight data, the system first analyzes the real-time flight status of the UAV, detects abnormal flight activities, and promptly issues alarms and stores evidence of abnormal behavior. After the UAV lands and the flight activity ends, the system organizes the flight data, structures it, generates a itinerary, and encrypts it using an attribute cryptography algorithm. The encrypted itinerary data is stored in the database, and the itinerary tag is stored on the blockchain for evidence.

[0101] (5.3) Data Usage Phase. Data users retrieve the encrypted itinerary from the database, attempt to decrypt it using an attribute cryptography algorithm, and then compare the decrypted data with the on-chain itinerary tag to verify its integrity. Plaintext itinerary data that passes integrity verification can be used for downstream data processing tasks.

[0102] The complete business process of this invention includes the following steps:

[0103] 1. Flight Entity Registration

[0104] (1.1) Flight entities include users, flight licenses and drones, and all flight entities must be registered;

[0105] (1.2) User registration, such as Figure 5 "Local DABE Initialization" and Figure 4 As shown in "Flight Entity Registration", the specific steps include:

[0106] (1.2.1) The user requests the DABE global parameters from the server of the algorithm support module and uses the DABE global parameters to initialize the user terminal of the algorithm support module; the user registers on the user terminal of the algorithm support module, uses the email address as the GID, and generates a public-private key pair (PK) for asymmetric encryption. asy SK asy The key pair (upk, usk) is used for encryption of the user's public and private keys. The asymmetric encryption private key SK is used for encryption. asy The private key (usk) of the encryption authority is securely stored locally;

[0107] (1.2.2) Users register in the Flight Identity Authentication and Access Management module, select user level, set email, login password, name, and pass the asymmetric encryption public key PK. asy The user uploads the private key (UPK) of the attribute encryption authority to the server of the algorithm support module. After registration, the user can obtain a unique identifier number in the system.

[0108] (1.2.3) Call the CreateUser function of the user contract from the blockchain, and store the user's unique identifier ID and asymmetric encryption public key PK. asy The private key (UPK) of the encryption authority is uploaded to the blockchain.

[0109] (1.3) Users can only perform flight activities after obtaining a pilot's license. Pilot license registration is as follows: Figure 4 As shown in "Flight Entity Registration", the specific steps include:

[0110] (1.3.1) Users register their flight licenses in the flight identity authentication and permission management module, and upload their flight license number, flight license level and flight license expiration time;

[0111] (1.3.2) Call the CreateLicense function of the driver_license contract from the blockchain to upload the flight license number and flight license data hash value to the blockchain.

[0112] (1.4) Drone registration, such as Figure 4 As shown in "Flight Entity Registration", the specific steps include:

[0113] (1.4.1) Users register drones in the flight identity authentication and permission management module, upload the drone serial number, specifications and airworthiness level, and obtain a unique identifier ID for the drone in the system after registration;

[0114] (1.4.2) Call the DroneRegister function of the drone contract from the blockchain to upload the drone serial number, the unique identifier of the user to which the drone belongs, and the drone data hash value to the blockchain, and obtain a 256-bit drone digital ID; (1.4.3) If the drone needs to be revoked, the drone status on the blockchain can be modified from the drone digital ID.

[0115] 2. Attribute Declaration, Application and Authorization (2.1) Users can declare new attributes Attr x The new attribute belongs to the user who declared it, and the attribute declaration is as follows: Figure 5 As shown in the "Attribute Declaration" section, the specific steps include:

[0116] (2.1.1) Users can declare new attributes in the client-side of the algorithm support module. For the new attribute Attr that the user wants to declare... x Choose a random number Calculate ASK = y x As a private key for attributes Use it as the attribute public key and store ASK securely locally;

[0117] (2.1.2) The user declares a new attribute to the server of the algorithm support module and uploads the new attribute Attr. x The attribute's corresponding APK is then uploaded to the blockchain by calling the DeclareAttr function of the attribute contract. This uploads the attribute ID, the attribute declaration user ID and GID, the attribute name, and the attribute public key APK.

[0118] (2.2) Users can request the Attr attribute from other users. x ,like Figure 5 As shown in "DABE Attribute Application and Authorization", the specific steps include:

[0119] (2.2.1) User i Can be sent to User j Apply for its exclusive attribute Attr x Send the attribute owner GID to the server of the algorithm support module. j and attribute Attr x Obtain the attribute application number;

[0120] (2.2.2) Call the ApplyAttr function of the attribute contract from the blockchain to pass the attribute request number, attribute requester ID, and GID. i And the attribute ID is uploaded to the blockchain;

[0121] (2.3) Users can query attribute requests and authorize or deny attributes, such as... Figure 5As shown in "DABE Attribute Application and Authorization", the specific steps include:

[0122] (2.3.1) User j You can query pending and initiated attribute requests to obtain the attribute request number and the attribute requester's GID. i and attribute Attr x ;

[0123] (2.3.2) If User j Agree to authorize attributes, calculate As a User i Authorization attribute private key And retrieve User from the server of the algorithm support module. i Asymmetric encryption public key PK asy Encrypt the private key for the authorization attribute to obtain And send it to the server of the algorithm support module;

[0124] (2.3.3) If User j If the authorization attribute is denied, an empty value is sent to the server of the algorithm support module;

[0125] (2.3.4) Call the ProcessAttrApp function of the attribute contract from the blockchain to upload the attribute application number, application status (authorized / rejected) and encrypted authorized attribute private key to the blockchain;

[0126] (2.3.5) Authorized users can synchronize attributes with the server of the algorithm support module, obtain the authorized attributes and the encrypted private key of the authorized attributes, and decrypt them to obtain the private key of the authorized attributes.

[0127] 3. Flight Activity Application and Filing (3.1) Before conducting flight activities, users should obtain flight activity approval from the regulatory authority and submit a flight activity application, such as... Figure 4 As shown in the "Flight Activity Application" document, the specific steps include:

[0128] (3.1.1) Based on the flight activity approval, the user applies for a flight activity to the flight management module, uploads the flight activity approval number, flight start time, flight area, take-off and landing locations, maximum flight speed and entry / exit type, and obtains the flight token corresponding to the flight activity;

[0129] (3.1.2) Call the CreateApproval function of the flight_approval contract from the blockchain to upload the flight activity approval number and the hash value of the flight activity approval to the blockchain; call the CreateToken function of the flight_token contract to upload the flight token number, flight token status and flight token hash value to the blockchain.

[0130] (3.2) Before performing flight activities, users shall submit a pre-flight report to the flight management module, such as... Figure 4 As shown in the "Pre-flight Reporting" document, the specific steps include:

[0131] (3.2.1) The user uploads to the flight management module the user performing the flight activity, the drone used in the flight activity, the flight token, and the attribute encryption policy used for itinerary encryption;

[0132] (3.2.2) The flight management module sends flight license information and UAV information to the flight identity authentication and permission management module for verification. If the verification fails, the process is terminated.

[0133] (3.2.3) The flight management module sends the attribute encryption policy to the server of the algorithm support module for verification. The server of the algorithm support module checks the policy. If the verification fails, the process is terminated.

[0134] (3.2.4) Call the ActivateToken function of the flight_token contract from the blockchain to activate the flight token and modify the on-chain state;

[0135] (3.2.5) The flight management module sends the flight record number to the user.

[0136] 4. Commence flight activities

[0137] (4.1) Flight activities mainly include four parts: takeoff signals, flight data, landing signals, and flight activity itinerary generation;

[0138] (4.2) When the drone takes off, if Figure 4 As shown in the "Takeoff" diagram, the specific steps include:

[0139] (4.2.1) The UAV sends a takeoff signal to the flight management module, including the flight activity number, UAV serial number, takeoff time and takeoff location;

[0140] (4.2.2) The flight management module obtains the drone operator information from the flight identity authentication and permission management module and pushes the take-off signal to the drone operator.

[0141] (4.3) During drone flight, real-time flight data needs to be synchronized to the flight management module, such as... Figure 4 As shown in the "Flight / Radar Scan" section, the specific steps include:

[0142] (4.3.1) During the flight of the UAV, real-time flight data needs to be synchronized to the flight management module in real time, including flight activity number, UAV serial number, real-time time, cumulative flight time, latitude and longitude, altitude, relative flight altitude, flight speed and other information;

[0143] (4.3.2) During the flight of the UAV, the radar scans the UAV and sends the scanned UAV flight data to the flight management module. The scanned flight data includes information such as UAV serial number, real-time time, latitude and longitude, altitude, and flight speed.

[0144] (4.3.3) The flight management module obtains drone operator information and drone owner information from the flight identity authentication and permission management module, and pushes real-time flight data to the drone operator;

[0145] (4.3.4) If the real-time flight data does not match the flight activity application during the drone flight, an abnormal alarm will be sent to the drone operator and drone owner. Abnormal types include "flight activity timeout", "drone not registered", "drone number does not match the report", "flight position exceeds the flight area", "flight too high", "flight too fast", etc.

[0146] (4.4) When the drone lands, if Figure 4 As shown in the "Takeoff" diagram, the specific steps include:

[0147] (4.4.1) The UAV sends a landing signal to the flight management module, including the flight activity number, UAV serial number, takeoff time and takeoff location;

[0148] (4.4.2) The flight management module obtains the drone operator information from the flight identity authentication and permission management module and pushes the landing signal to the drone operator.

[0149] (4.5) After the flight activity is completed, the flight management module will generate a flight itinerary, such as... Figure 4 As shown in the "Itinerary Generation" section, the specific steps include:

[0150] (4.5.1) The UAV sends the flight activity number, take-off signal, real-time flight data, radar scan data, and landing signal to the flight management module to generate a itinerary;

[0151] (4.5.2) The flight management module sends the itinerary and attribute encryption strategy to the server of the algorithm support module. The server of the algorithm support module performs encryption. The encryption steps are as follows: using an n×l access control matrix A and the mapping relationship ρ between the matrix rows and the attribute set, select a random number. and a random vector s is the first element of vector v; in choosing a random variable whose first element is 0 For a certain row A in matrix A k Choose a random number The ciphertext structure can be represented as in:

[0152] C0 = Me(g,g) s ,

[0153] (4.5.3) Call the CreateFlightRecord function of the flight_record contract from the blockchain to upload the flight record number and itinerary data hash value to the blockchain.

[0154] 5. View flight data

[0155] (5.1) Users can obtain the encrypted itinerary and decrypt it, such as... Figure 5 As shown in "Data Encryption and Decryption", after obtaining the ciphertext, it is decrypted on the user end of the algorithm support module. If the attribute conditions are met, the plaintext of the itinerary can be decrypted; otherwise, the decryption fails.

[0156] (5.2) In the decryption algorithm, the inputs are the ciphertext CT and the attribute {K} used by the user to match the access control policy. x GID i} and globally public parameters. The decryptor first needs to calculate Make ∑ k ω k A k = (1, 0, ..., 0). Then, for each row k, calculate... Next, we multiply and accumulate the values ​​obtained from each row by power, using the formula ∑ k (A k ·v)ω k =v·(1,0,…,0)=s and ∑ k (A k ·w)ω k =w·(1,0,…,0)=0 can be obtained Ultimately, the plaintext message M = C0 / e(g,g) can be obtained. s .

Claims

1. A blockchain and attribute-based cryptography based trusted low-altitude perception and data notarization platform, characterized in that The system comprises a user interaction layer, a logic processing layer, and a blockchain and storage layer, the user interaction layer comprises a trusted low-altitude sensing and flight data security recording software platform, the logic processing layer comprises a flight identity authentication and permission management module and a flight state sensing and anomaly detection module, and the blockchain and storage layer comprises a blockchain, an algorithm support module and an IPFS; on a server interacting with the blockchain, a server end of the flight identity authentication and permission management module, the flight state sensing and anomaly detection module and the algorithm support module is built, and a user end of the algorithm support module is built on a server of the user, which is responsible for locally saving a user's asymmetric key private key, a user private key, an attribute private key and an authorized attribute private key, providing key pair generation, attribute creation, attribute authorization and data decryption operation support related to private data, ensuring that user data is stored and used locally, and no private information is exposed to the outside; wherein: (1) The trusted low-altitude sensing and flight data security recording software platform is connected with a front-end user interface, accepts user registration, aircraft management and permission management information, and reports flight data information in real time and synchronizes flight data and airspace state information; specifically as follows: (1.1) A user operation page is provided for the user, a user-friendly interactive experience is provided, a local user end is called to execute sensitive data and key generation, encryption and decryption, storage, and a remote server end is called to execute user, unmanned aerial vehicle, operator management and flight activity whole-process tracking management functions; it is ensured that the user does not need to care about the service deployment architecture, can use all the capabilities of the system through a unified front-end entrance, and completes the trusted low-altitude sensing and flight data security recording task; (1.2) An interface for a tower company's station node to expose and report flight data is provided, data collection, analysis and storage service capabilities are provided; two interfaces are exposed to the tower station node, one is a flight data reporting interface for the unmanned aerial vehicle to actively report, and the other is a recording interface for suspicious flight activity data monitored by the tower station-mounted monitoring scanning radar when scanning the airspace; the former is responsible for receiving, analyzing, arranging and storing flight activity data actively reported by the unmanned aerial vehicle during flight, and issuing an alarm for abnormal flight activity; the latter is responsible for receiving and recording suspicious flight activity data scanned by the tower station-mounted radar, and providing a reliable record for future analysis, verification and accountability; (2) The flight identity authentication and permission management module is responsible for management and identification of flight activity participants and related data, including users, unmanned aerial vehicles, unmanned aerial vehicle operation certificates and approved flight routes; is responsible for user attribute declaration, application and granting operation; uses blockchain and cryptography related technologies to generate a unique digital identity for the aircraft, performs identity authentication and automatic verification and authorization of flight permission, sends the request processing result to the trusted low-altitude sensing and management software platform, is responsible for management and identification of flight activity participants and related data, including users, unmanned aerial vehicles, unmanned aerial vehicle operation certificates and approved flight routes; is responsible for user attribute declaration, application and granting operation; specifically as follows: (2.1) After the user registers, register the unmanned aerial vehicle information, register a certain unmanned aerial vehicle as the unmanned aerial vehicle owned by oneself; register the unmanned aerial vehicle operation certificate information, bind the user's own unmanned aerial vehicle operation certificate; register the approved route information, report the user's application and approved route information from the management agency; (2.2) Registering unmanned aerial vehicle information requires providing the unmanned aerial vehicle serial number as the unique identifier of the unmanned aerial vehicle in the real world; the system generates a unique digital identity based on this information and other related information based on the national SM3 algorithm, which is used for identity authentication and data association in the system; (2.3) Registering unmanned aerial vehicle operation certificate information requires providing the unmanned aerial vehicle operator certificate obtained from the relevant agency, and generating the corresponding "electronic operator certificate" as the system identifier based on the national SM3 algorithm. Only the user who owns the operator can be approved to fly the unmanned aerial vehicle; (2.4) Report the route information, the user reports the approved route information from the relevant unit to the platform; the system extracts the flight token based on the key information, which is used as the flight certificate in the system, and generates the token ID as the unique identifier based on the national SM3 algorithm; The whole process of flight activity management is based on the flight token; (2.5) User attribute management; based on the DABE decentralized attribute-based encryption algorithm, each user declares the attributes managed by himself, requests other user-managed attributes, and is authorized by the manager user of the attribute, and generates an authorized attribute private key; thereafter, the user encrypts the data with the attribute public key and decrypts the ciphertext with the attribute private key; Only users who meet the attribute policy expression specified during encryption can successfully decrypt to obtain plaintext information; (3) The flight state sensing and anomaly detection module is responsible for the automatic management of the whole process of unmanned aerial vehicle flight activities such as take-off, flight, landing, and trip sheet generation and confirmation, real-time detection of abnormal flight conditions, and can receive and process the suspicious flight activities scanned by the radar carried by the tower site; flight data encryption storage to ensure privacy; receive information from the trusted low-altitude sensing and flight data security recording software platform, collect real-time flight data, then transmit and analyze the data, and issue an alarm for abnormal behavior; Details as follows: (3.1) Before the unmanned aerial vehicle takes off, it reports before taking off, provides approved route information, current user's unmanned aerial vehicle operation certificate, and digital identity of the unmanned aerial vehicle used for preparation of take-off; The system compares the three to be consistent, and then automatically executes the flight permission release instruction by the blockchain smart contract to allow take-off; otherwise, it is not allowed to take off; In addition, the attribute encryption policy expression needs to be provided, and the data generated during the flight process; (3.2) During the flight of the UAV, according to the existing UAV management regulations, the current flight state information needs to be reported in real time; the station cluster of the tower company acts as a distributed signal receiving node, collects the flight data reported by the UAV, and calls the system interface to transmit the data to the system of the application; the system detects various abnormal behaviors such as flight activity timeout, overspeed, and overheight, and uses the geographic fence technology and the spatial geometric relationship judgment method to monitor the preset flight area boundary in real time, thereby identifying and warning abnormal behaviors such as border crossing flight; the platform synchronizes the flight state and issues an abnormal behavior warning to the user front end in real time through the SSE technology; in addition to triggering the warning, the abnormal flight behavior generates an abnormal activity notification sheet in the system and is stored for evidence, so as to facilitate the accountability in the future; (3.3) After the UAV lands, a landing signal is sent, which is received by the tower and reported to the system; the system immediately integrates all the flight trajectory data generated in the flight activity to form a flight activity itinerary sheet; the itinerary sheet data is expressed by using the attribute encryption strategy expression specified in step (3.1), and is encrypted and stored after calling the algorithm support module, so as to ensure that the flight record privacy is not leaked, and to allow users meeting the strategy to access these data under control; (3.4) The tower deploys radars on distributed station resources to form a high-density airspace detection grid, which scans suspicious flight activities in the airspace in real time and reports them to the platform; the platform stores the suspicious flight activity data for evidence, which is used for comparison and investigation in the future; (4) Algorithm support module, responsible for integrating DABE decentralized attribute-based encryption algorithm, providing encrypted storage, privacy protection, one-to-many transmission and fine-grained access control capabilities for flight data; specifically as follows: (4.1) User generation; when each user of the platform registers, the attribute password module is called to generate the user public and private key pair required for attribute password, and the asymmetric encryption public and private key pair used to encrypt the transmission of the authorized attribute private key; the public key is uploaded to the server, and the private key is saved locally; all uses of the private key are performed locally to avoid leaking privacy; (4.2) Attribute declaration; the user declares the attributes managed by himself, and generates the public and private keys of the attributes; the public key is uploaded to the server, and the private key is saved locally; (4.3) Attribute application and grant; user A requests authorization of a certain attribute from user B, user B generates the authorized attribute private key corresponding to user A in the user local, and uploads it to the server after being encrypted with the asymmetric encryption public key of user A; user A can obtain the ciphertext of the authorized attribute private key from the server, and then call the decryption function locally to obtain the authorized attribute private key and save it in the user local; (4.5) Data encryption and decryption; after specifying the attribute strategy expression used for encryption and decryption, the algorithm module uses the public key of the relevant attribute uploaded to the server to encrypt the data, and the ciphertext data is stored in the server; any user obtains the ciphertext from the server, calls the local, and uses the authorized attribute private key stored locally to decrypt; any user meeting the strategy expression successfully decrypts to obtain the plaintext; various attributes are freely combined in the strategy expression to provide fine-grained data access permission control capability.

2. The trusted low-altitude sensing and data notarization platform based on blockchain and attribute cryptography according to claim 1, characterized in that The blockchain is designed by using Chang'an chain scheme; the tower base station is used as a distributed node to enhance the monitoring coverage and data acquisition capacity, and to ensure the integrity and reliability of the data; the attribute password scheme uses a decentralized attribute password algorithm, including system global setting Global SetUp, authority setting Authority SetUp, encryption Encrypt, key generation Key Generate and decryption Decrypt, and the specific process is as follows: Algorithm one: Global SetUp: Select an N-order bilinear pairing: e: G x G -> G T ; where: G is a subgroup of an elliptic curve over a finite field; G T is a multiplicative subgroup of an extension field of a prime-order finite field; wherein: N = p1p2p3, p1p2p3 are three prime numbers, N is a composite number, representing the order of the group G and the group G T ; Let be a p1-order subgroup of the group G, take the generator g1 of the group , The public parameters are {e, N, g1}, that is, the bilinear pair, the order of the group and the generator of the subgroup; Moreover, a hash function H: {0,1} * → G; this hash function maps arbitrary strings (represented as 01 bits) to elements of the group G; the hash function H should be treated as a random oracle in the proof of security of the cryptosystem; Algorithm two: Authority SetUp: In attribute-based encryption, is a ring consisting of modulo-N addition and modulo-N multiplication; For each attribute i of the authority, randomly select an element The public key is: The private key is: Algorithm three: Encrypt: The input of algorithm three Encrypt includes: Message M to be encrypted ∈ G T , Access control matrix A, A is an n x l order matrix, representing the access control matrix in the linear secret sharing scheme; attribute mapping p, p is an n-dimensional row vector, which maps each row of the matrix to a corresponding attribute in the access control strategy; the access control matrix A and the attribute mapping p together constitute the encryption strategy specified in the encryption process; public keys corresponding to all attributes in the encryption policy The calculation process of algorithm three Encrypt is as follows: Randomly selected elements and vector where Here element s is the secret in the encryption process, and is the blinding factor in the encryption process; vector is an l-dimensional vector, the first bit is the secret s, and the other bits are randomly generated elements; randomly selected vector where Vector is an l-dimensional vector, the first element must be 0, and the other bits are randomly generated elements; Computing the secret share λ x and w x where and For each row A of the access control matrix A x It is also desirable to randomly select elements The calculation result of algorithm three Encrypt is as follows: Computing the first part of the ciphertext C0, C0 = M e(g1, g1) s ; calculating the second part of the ciphertext C 1,x , calculating the third part of the ciphertext C 2,x , computing the fourth part of the ciphertext C 3x , The four parts together constitute the ciphertext result obtained by encryption; Algorithm four: Key Generate: For the user with global identity GID, when the user applies attribute i, the corresponding authority grants the corresponding user public key of attribute i; the user public key calculation formula is as follows: Algorithm five: Decrypt: The input of algorithm five, Decrypt, includes the output ciphertext of algorithm three and the output key of algorithm four. First, according to the second part C 1,x , the third part C 2,x , the fourth part C 3x and the user public key K i,GID , the following is calculated: Next, a set of constants needs to be calculated satisfies x c x ·A x = (1, 0,..., 0); according to the principle of linear secret sharing scheme, if the decryption party meets the decryption condition, Computing Compute M = C0 / e(g1, g1) s ; M is the decrypted message, and is the output of Algorithm 5.

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