Key storage device and control method thereof
By combining optical isolation modules, bio-fuse storage modules, and three-factor authentication units, the shortcomings of existing hardware key storage devices in terms of security and user experience are addressed, achieving multi-dimensional security protection and strict device ownership management, thereby improving the security and convenience of key storage.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-28
- Publication Date
- 2026-03-10
AI Technical Summary
Existing hardware key storage devices have limitations in terms of security depth and comprehensiveness. The data collection process lacks thorough physical isolation, biometric storage is easily tampered with, multi-factor authentication is not rigorous and lacks sufficient accuracy, changes in device ownership are not strictly managed, key data import and export methods are simplistic and error-prone, and the user experience is poor.
It employs an optically isolated offline text recognition module, a bio-fuse storage module, a three-factor authentication unit, an epoxy self-destruct structure, and a data communication interface to achieve multi-dimensional security protection. The bio-fuse storage module writes user biological data upon initial activation and permanently fuses the rewrite circuit. The three-factor authentication unit performs multi-dimensional verification. The epoxy self-destruct structure monitors the disassembly and destruction of the storage module and supports multiple data import and export methods.
It achieves multi-dimensional security protection throughout the key storage process, improves identification accuracy and user experience, prevents unauthorized access, strengthens the physical and logical dual security of the device under extreme conditions, ensures key data security, and achieves strict device ownership transfer and dedicated security for key storage.
Smart Images
Figure CN121644064A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of digital security hardware technology, and in particular to a key storage device and its control method. Background Technology
[0002] With the widespread application of digital encryption technology in finance, data security, and other fields, the storage technology of keys, as core access credentials, has gradually evolved from software-dependent to hardware-independent. Early key storage relied mainly on encryption software on computers or mobile terminals, which was vulnerable to system vulnerabilities, network attacks, and malicious programs, making security difficult to guarantee. Subsequently, dedicated hardware key storage devices emerged, reducing network threats through offline storage modes and gradually incorporating mechanisms such as password verification, single biometric identification, and physical button triggering, forming a basic security architecture of offline isolation and multi-dimensional verification, which has become the mainstream technology direction for key storage today.
[0003] Existing hardware key storage devices still have significant limitations in the depth and comprehensiveness of security protection. In the critical information collection stage, the acquisition of data such as mnemonic phrases often lacks thorough physical isolation design. Potential electrical signal interactions may exist between the module and the main control unit, leading to the risk of data interception during conversion and transmission. Biometric storage often uses rewritable storage media, which cannot achieve permanent locking after biometric data is written, posing a risk of malicious tampering or replacement. Anti-disassembly protection mechanisms are mostly limited to vibration detection alarms or simple function locks, making it difficult to physically damage the core storage module when the device is forcibly disassembled, thus failing to fundamentally prevent key leakage.
[0004] Furthermore, the verification logic of multi-factor authentication is not rigorous enough, and some schemes do not combine real-time timestamps and deep feature comparison, resulting in insufficient verification accuracy. During the ownership transfer process, the original user identity verification process is simplified, and the access control for writing new user data lacks rigid constraints. Moreover, in the face of brute-force attacks that fail multiple times, there is a lack of tiered temporary locking and emergency protection mechanisms, making it difficult to cope with persistent malicious attacks. In addition, the existing devices have extremely simple and cumbersome methods for importing and exporting key data, relying heavily on manual input, especially for long strings of keys or mnemonic phrases. The input process is time-consuming and prone to errors, resulting in a poor user experience. At the same time, in terms of the secure transfer of device ownership or control, there is a lack of mechanisms for reliably binding and verifying users' legal identity information in an offline environment, making it difficult to achieve both convenient and strict ownership management. Summary of the Invention
[0005] The purpose of this invention is to overcome the above-mentioned problems and provide a key storage device and its control method, which can support a variety of secure and convenient data import and export methods, improve the recognition accuracy, and realize strict device ownership management based on legal identity information in an offline environment.
[0006] To achieve the above objectives, the present invention adopts the following technical solution:
[0007] A key storage device includes an optically isolated offline text recognition module, a biometric fuse storage module, a three-factor authentication unit, an epoxy self-destruct structure, a data communication interface, and a main control module. The optically isolated offline text recognition module, the biometric fuse storage module, the three-factor authentication unit, the epoxy self-destruct structure, and the data communication interface are electrically connected to the main control module. The optically isolated offline text recognition module collects external text information and converts it into encrypted data, which is then transmitted to the main control module. The data communication interface is used to connect to external devices to receive external data or send stored data. After receiving the initial activation signal, the biometric fuse storage module writes the user's fingerprint and iris data and permanently fuses the rewrite circuit. The three-factor authentication unit receives external multi-dimensional authentication information and generates an authentication signal, which is transmitted to the main control module. The main control module controls the biometric fuse storage module to output key data or remain locked based on the authentication signal. The epoxy self-destruct structure monitors the device for disassembly attempts and generates a status signal. An abnormal signal triggers the expansion and curing of the biometric fuse storage module, damaging it.
[0008] Furthermore, the optically isolated offline text recognition module incorporates an OCR engine and an image processing unit, and is electrically isolated from the main control module via physical isolation. When the module acquires external text information, it first obtains a text image through the optical components. The image processing unit preprocesses the text image and corrects recognition errors. Then, the OCR engine converts the text image into text data, which is then encrypted to obtain encrypted text data. The encrypted text data is sent to the main control module through a unidirectional transmission channel. The encryption satisfies the following conditions:
[0009]
[0010] Among them, T enc The encrypted text data is represented by T, where T is the original text data converted by the OCR engine, H represents the hash algorithm, and IV is the initialization vector for text encryption. This represents the XOR operation.
[0011] Furthermore, the biometric fuse storage module includes a biometric acquisition component and a fuse storage chip, which are electrically connected. Upon initial activation, the biometric acquisition component acquires the user's fingerprint and iris data, converts them into feature vectors respectively, and then generates a fused feature value that satisfies the following:
[0012]
[0013] Among them, V fusion V represents the biofusion characteristic value. f V is the fingerprint feature vector. i Let H be the iris feature vector, and H represent the hash algorithm. This represents the XOR operation;
[0014] Once the fused feature value is written to the fuse memory chip, the rewrite circuit is permanently blown, allowing only read operations and preventing modification or erasure of the written fused feature value.
[0015] Furthermore, the three-factor authentication unit includes a biometric authentication component, a password input component, and a physical button component, all of which are electrically connected to the main control module. Authentication is performed according to the following steps:
[0016] Step S11: The biometric verification component acquires real-time fingerprint and iris data, converts it into real-time feature vectors, and then generates real-time fusion feature values, satisfying the following:
[0017]
[0018] Among them, V′ fusion V′ represents the real-time biological fusion feature value. f V′ is the real-time fingerprint feature vector. i Here, H represents the real-time iris feature vector, and H denotes the hash algorithm. This indicates an XOR operation; the main control module calls the fusion feature value in the fuse storage chip, calculates the similarity between the real-time biological fusion feature value and the fusion feature value in the fuse storage chip, and when the similarity between the real-time biological fusion feature value and the fusion feature value in the fuse storage chip is greater than or equal to the preset threshold S1, proceeds to step S12.
[0019] Step S12: The password input component receives a 6-digit dynamic password, generates a password verification value, and satisfies:
[0020]
[0021] Among them, P check Here, P is the password verification value, T is the current verification timestamp, and H represents the hash algorithm. This represents the XOR operation;
[0022] The main control module calls the pre-stored password baseline verification value P ref When the password verification value is equal to the pre-stored password baseline verification value, proceed to step S13;
[0023] Step S13: The physical button component receives the pressing operation and monitors the pressing duration t. When t≥3 seconds, it sends a verification pass signal to the main control module. After receiving the signal, the main control module generates a control signal that allows the bio-fuse storage module to output key data.
[0024] Furthermore, the epoxy self-destruct structure includes a sensor assembly, a curing drive assembly, and an epoxy containment cavity; the sensor assembly is electrically connected to the curing drive assembly, and the curing drive assembly is physically connected to the epoxy containment cavity; the sensor assembly detects the equipment vibration acceleration and power supply voltage in real time, and when the equipment vibration acceleration is greater than or equal to a preset vibration threshold, the power supply voltage is less than a preset minimum voltage, or the power supply voltage is greater than a preset maximum voltage, it sends a trigger signal to the curing drive assembly; after receiving the trigger signal, the curing drive assembly activates the heating element to heat the curing agent in the epoxy containment cavity, and the curing agent and epoxy mix and expand to cure, damaging the storage chip and data transmission line of the bio-fuse storage module.
[0025] Furthermore, the transfer of equipment ownership shall be carried out in accordance with the following steps:
[0026] Step S21: The biometric verification component collects the original user's real-time fingerprint and iris data and generates the original user's real-time fusion feature value; the main control module calculates the similarity between the original user's real-time fusion feature value and the fusion feature value in the fuse storage chip. When the similarity is greater than or equal to the preset threshold S2, proceed to step S22.
[0027] Step S22: The password input component receives the security password entered by the original user and generates a password verification value; the main control module calls the pre-stored password baseline verification value W. ref When the password verification value is compared with the pre-stored password baseline verification value W ref If they are equal, proceed to step S23;
[0028] Step S23: The main control module receives the ID card number and mobile phone number input by the original user, calculates their hash values, and compares them with the pre-stored ID card number hash values and mobile phone number hash values. If they match, proceed to step S24.
[0029] Step S24: The main control module detects no abnormal signals in the epoxy self-destruct structure, and the impedance of the fuse storage chip's fuse circuit is within the preset range R1 to R2; the main control module temporarily activates the rewrite permission of the bio-fuse storage module, controls the bio-acquisition component to collect the new user's fingerprint and iris data and generate the new user's fusion feature value, erases the original fusion feature value and writes the new user's fusion feature value, and permanently closes the rewrite permission of the bio-fuse storage module.
[0030] Furthermore, the main control module has a built-in verification failure counter; when any step in the three-factor authentication fails, the verification failure counter accumulates the number of failures; when the number of failures is greater than or equal to the preset trigger count, the main control module controls the biological circuit breaker storage module to enter a temporary lockout state; the temporary lockout duration meets the following requirements:
[0031]
[0032] Among them, t lockt0 is the temporary locking duration, n is the cumulative number of failures, and n1 is the preset number of times the temporary lock is triggered.
[0033] In the temporary latched state, the three-factor authentication unit does not respond to any authentication requests, and the temporary latching duration does not exceed the preset maximum duration t. max .
[0034] Furthermore, the fuse memory chip is divided into a feature storage area and a key storage area; the feature storage area stores bio-fusion feature values, and the key storage area stores encryption key data, with encryption satisfying:
[0035]
[0036] Among them, K enc The encrypted key data, where K is the original key and IV is the encrypted key data. k Let V be the initialization vector for key encryption, E represent the symmetric encryption algorithm, and V be the initialization vector for key encryption. fusion For the biological fusion feature value in the feature storage area, ⊕ represents the XOR operation;
[0037] Read and write operations in the key storage area must first be compared with the fused feature value in the feature storage area. Only after the comparison is successful can the read and write operations be performed. If the comparison fails, the key storage area remains locked.
[0038] Furthermore, the epoxy self-destruct structure also includes an emergency trigger component; the emergency trigger component is electrically connected to the main control module; when the number of three-factor verification failures is greater than or equal to the preset emergency count, and the preset emergency count is greater than the preset trigger count, the main control module sends an emergency signal to the emergency trigger component; after receiving the emergency signal, the emergency trigger component directly controls the curing drive component to start the epoxy curing process, without waiting for the sensor component's detection results; the preset emergency count is the hardware curing parameter at the time of the equipment's manufacture.
[0039] Furthermore, a method for controlling a key storage device includes the following steps:
[0040] Step S31: Device initialization, the optical isolation offline text recognition module encrypts the mnemonic phrase information and transmits it to the main control module, and / or receives external data through the data communication interface and encrypts and transmits it to the main control module, the main control module generates encryption key data and stores it;
[0041] Step S32: Upon initial activation, the bio-acquisition component generates user fusion feature values and writes them into the fuse storage chip, triggering the rewrite circuit to blow.
[0042] Step S33: Key retrieval. After the three-factor authentication unit completes biometric comparison, dynamic password verification and physical key detection, the main control module decrypts and obtains the original key.
[0043] Step S34: Data output, the main control module sends the original key to the external device through the data communication interface;
[0044] Step S35: Anti-disassembly protection: When the sensor assembly detects abnormal vibration or voltage, it triggers the epoxy-cured damaged biological fuse storage module.
[0045] Step S36: Ownership change. After verifying the original user's identity and device status, write the new user's fusion feature value.
[0046] The advantages of this invention are:
[0047] 1. This invention encrypts the collected text information by setting up an optically isolated offline text recognition module, and introduces an image processing unit for preprocessing and recognition error correction. It is combined with a biometric fuse storage module to write user biometric data after initial activation and permanently fuse the rewrite circuit. Then, combined with a three-factor authentication unit, it sequentially completes biometric feature comparison, dynamic password verification and physical key detection. The main control module controls the key output according to the verification results, and the key data can be securely imported or exported through the data communication interface. This realizes multi-dimensional security protection for key storage throughout the entire process of collection, input, storage and retrieval, effectively blocking unauthorized access, significantly improving usability and accuracy, ensuring key data security and reducing the risk of tampering or theft.
[0048] 2. This invention uses a sensor component with an epoxy self-destruct structure to monitor the vibration acceleration and power supply voltage of the device in real time. When an abnormality occurs, the curing drive component is triggered to heat the curing agent, causing the epoxy to expand and cure, damaging the bio-fuse storage module. At the same time, when the number of verification failures reaches a preset emergency number, the emergency trigger component directly initiates the self-destruct process. Combined with the temporary locking mechanism after verification failure, this invention achieves anti-disassembly and brute-force protection for the device, avoiding key leakage caused by disassembly of the device or multiple incorrect verifications, and strengthening the physical and logical dual security of the device under extreme conditions.
[0049] 3. This invention verifies the original user's biometrics, security password, ID number, and mobile phone number during ownership changes. After confirming the device is functioning correctly, it temporarily activates the biometric fuse storage module's rewrite permissions, writes the new user's biometric data, and then permanently closes the permissions. This achieves a strict and reliable transfer of device ownership in an offline environment. Simultaneously, the fuse storage chip is divided into a feature storage area and a key storage area. Key reading and writing require prior comparison with the feature area, ensuring the independence and associated security of biometric and key storage. This further enhances the dedicated security of key storage and accurately meets the security and management needs during user identity changes. Attached Figure Description
[0050] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application.
[0051] In the attached diagram:
[0052] Figure 1 This is a flowchart illustrating the key retrieval process of a key storage device and its control method in Embodiment 1. Detailed Implementation
[0053] The present invention will now be described in detail and specifically through specific embodiments to enable a better understanding of the invention. However, the following embodiments do not limit the scope of protection of the present invention.
[0054] Example 1
[0055] like Figure 1 As shown, a key storage device includes an optically isolated offline text recognition module, a biometric fuse storage module, a three-factor authentication unit, an epoxy self-destruct structure, a data communication interface, and a main control module. The optically isolated offline text recognition module, the biometric fuse storage module, the three-factor authentication unit, the epoxy self-destruct structure, and the data communication interface are all electrically connected to the main control module. The optically isolated offline text recognition module collects external text information and converts it into encrypted data, which is then transmitted to the main control module. The data communication interface is used to connect to external devices, receive external data, or send stored data. After receiving the initial activation signal, the biometric fuse storage module writes the user's fingerprint and iris data and permanently fuses the rewrite circuit. The three-factor authentication unit receives external multi-dimensional authentication information and generates an authentication signal, which is transmitted to the main control module. The main control module controls the biometric fuse storage module to output key data or remain locked based on the authentication signal. The epoxy self-destruct structure monitors the device for disassembly attempts and generates a status signal. An abnormal signal triggers the expansion and curing of the biometric fuse storage module, damaging it.
[0056] In a specific embodiment, the main control module of the key storage device uses an STM32L476RG microcontroller; the optically isolated offline text recognition module uses an OV7670 optical component paired with a Tesseract OCR engine and a dedicated image processing chip (FPGA); the biometric fuse storage module uses an FM25V02 fuse storage chip; the three-factor authentication unit includes an AS608 fingerprint module, an IRIS-200 iris module, and mechanical physical buttons; and the epoxy self-destruct structure uses an ADXL345 accelerometer sensor and a PT100 heating element. The data communication interface uses a USB Type-C interface chip. Each module is electrically connected to the main control module via GPIO, SPI, or UART interfaces. The optically isolated module acquires text images and converts them into encrypted data. After the biometric fuse storage module is activated for the first time, it writes the user's fingerprint and iris data and fuses the rewrite circuit. After successful three-factor authentication, the main control module controls the key output. When the epoxy self-destruct structure detects an attempt to disassemble, it destroys the storage module. The data communication interface enables secure data exchange with external devices, effectively achieving physical and logical dual protection throughout the key storage process and preventing unauthorized access.
[0057] Furthermore, the optically isolated offline text recognition module incorporates an OCR engine and an image processing unit, and is electrically isolated from the main control module via physical isolation. When the module acquires external text information, it first obtains a text image through the optical components. The image processing unit preprocesses the text image and corrects recognition errors. Then, the OCR engine converts the text image into text data, which is then encrypted to obtain encrypted text data. The encrypted text data is sent to the main control module through a unidirectional transmission channel. The encryption satisfies the following conditions:
[0058]
[0059] Among them, T enc The encrypted text data is represented by T, where T is the original text data converted by the OCR engine, H represents the hash algorithm, and IV is the initialization vector for text encryption. This represents the XOR operation.
[0060] In a specific embodiment, the optically isolated offline text recognition module incorporates a Tesseract 5.0 OCR engine and a dedicated image processing chip, and is electrically isolated from the main control module via an optocoupler 6N137. When acquiring text, the OV7670 optical component first obtains the image, which is then transmitted to the image processing unit for preprocessing such as grayscale conversion, binarization, noise reduction, and tilt correction. Subsequently, the OCR engine performs recognition, and the recognition result is corrected using an error correction algorithm based on a commonly used dictionary to obtain the original text data T. Assuming the initial text encryption vector IV is 567890, the calculation is first performed... The delello xorld 209 is obtained, and then processed by the SHA-256 hash algorithm H to obtain the encrypted text data T.enc The input data is a1b2c3d4e5f67890abcdef1234567890, which is then transmitted to the main control module via a unidirectional optical coupler channel. This design combines physical isolation and encryption algorithms, and introduces image optimization and intelligent correction to prevent electrical signal leakage during data transmission, significantly improving input accuracy and ensuring offline security for text information collection and transmission.
[0061] In a specific embodiment, the data communication interface uses a USB Type-C interface chip, which connects to the UART interface of the main control module. When a key needs to be imported through this interface, the device connects to the mobile phone via USB, and the main control module receives the key string "abcd1234" sent by the mobile phone and encrypts and stores it. When a key needs to be exported, after the user completes three-factor authentication, the main control module sends the decrypted original key to the application on the mobile phone via the USB interface, allowing the user to directly copy and use it, avoiding errors and tediousness from manual input.
[0062] Furthermore, the biometric fuse storage module includes a biometric acquisition component and a fuse storage chip, which are electrically connected. Upon initial activation, the biometric acquisition component acquires the user's fingerprint and iris data, converts them into feature vectors respectively, and then generates a fused feature value that satisfies the following:
[0063]
[0064] Among them, V fusion V represents the biofusion characteristic value. f V is the fingerprint feature vector. i Here, H represents the iris feature vector, H represents the hash algorithm, and ⊕ represents the XOR operation.
[0065] Once the fused feature value is written to the fuse memory chip, the rewrite circuit is permanently blown, allowing only read operations and preventing modification or erasure of the written fused feature value.
[0066] In a specific embodiment, the biometric acquisition components of the biometric fuse storage module are an AS608 fingerprint module and an IRIS-200 iris module, both of which are connected to the FM25V02 fuse storage chip via an I2C interface. Upon initial activation, the fingerprint module acquires the user's fingerprint to generate a feature vector V. f The values are 0.12, 0.23, 0.34, and 0.45, respectively. The iris module acquires iris feature vectors V to generate features. i The values are 0.56, 0.67, 0.78, and 0.89. Calculate them first. The values 0.44, 0.44, 0.44, 0.44, 0.44 were obtained, and then processed by the SHA-256 hash algorithm H to obtain the biofusion feature value V. fusionThe value is f0e4c2f76c58916ec258f246851bea09. After it is written into the fuse storage chip, the main control module sends a signal to blow the chip rewriting circuit, so that the biological data cannot be modified after it is written, thus preventing the biological characteristics from being tampered with at the hardware level.
[0067] Furthermore, the three-factor authentication unit includes a biometric authentication component, a password input component, and a physical button component, all of which are electrically connected to the main control module. Authentication is performed according to the following steps:
[0068] Step S11: The biometric verification component acquires real-time fingerprint and iris data, converts it into real-time feature vectors, and then generates real-time fusion feature values, satisfying the following:
[0069]
[0070] Among them, V′ fusion V′ represents the real-time biological fusion feature value. f V′ is the real-time fingerprint feature vector. i Here, H represents the real-time iris feature vector, and H denotes the hash algorithm. This indicates an XOR operation; the main control module calls the fusion feature value in the fuse storage chip, calculates the similarity between the real-time biological fusion feature value and the fusion feature value in the fuse storage chip, and when the similarity between the real-time biological fusion feature value and the fusion feature value in the fuse storage chip is greater than or equal to the preset threshold S1, proceeds to step S12.
[0071] Step S12: The password input component receives a 6-digit dynamic password, generates a password verification value, and satisfies:
[0072]
[0073] Among them, P check Here, P is the password verification value, T is the current verification timestamp, and H represents the hash algorithm. This represents the XOR operation;
[0074] The main control module calls the pre-stored password baseline verification value P ref When the password verification value is equal to the pre-stored password baseline verification value, proceed to step S13;
[0075] Step S13: The physical button component receives the pressing operation and monitors the pressing duration t. When t≥3 seconds, it sends a verification pass signal to the main control module. After receiving the signal, the main control module generates a control signal that allows the bio-fuse storage module to output key data.
[0076] In a specific embodiment, the biometric verification components of the three-factor authentication unit are an AS608 fingerprint module and an IRIS-200 iris module, the password input component is a 4×4 matrix keyboard, and the physical button component is a self-resetting mechanical button.
[0077] Step S11: Real-time acquisition of fingerprint feature vector V′ f The values are 0.13, 0.24, 0.35, and 0.46, respectively, for the iris feature vector V′. i Given 0.57, 0.68, 0.79, and 0.90, calculate... Its V-shaped structure within the fuse memory chip fusion The similarity is 92%, which is greater than the preset threshold S1 = 90%, so proceed to step S12;
[0078] Step S12: The user enters a 6-digit dynamic password P = 654321, the current verification timestamp T = 1717248000, calculate P. check =H(P⊕T), which is the same as the pre-stored password baseline verification value P. ref If consistent, proceed to step S13;
[0079] Step S13: The physical button is pressed for 5 seconds, satisfying t≥3 seconds. A verification pass signal is sent to the main control module. The main control module allows the bio-fuse storage module to output key data. Multi-dimensional verification ensures the uniqueness and security of the authorized operation.
[0080] Furthermore, the epoxy self-destruct structure includes a sensor assembly, a curing drive assembly, and an epoxy containment cavity; the sensor assembly is electrically connected to the curing drive assembly, and the curing drive assembly is physically connected to the epoxy containment cavity; the sensor assembly detects the equipment vibration acceleration and power supply voltage in real time, and when the equipment vibration acceleration is greater than or equal to a preset vibration threshold, the power supply voltage is less than a preset minimum voltage, or the power supply voltage is greater than a preset maximum voltage, it sends a trigger signal to the curing drive assembly; after receiving the trigger signal, the curing drive assembly activates the heating element to heat the curing agent in the epoxy containment cavity, and the curing agent and epoxy mix and expand to cure, damaging the storage chip and data transmission line of the bio-fuse storage module.
[0081] In a specific embodiment, the sensor components of the epoxy self-destruct structure are an ADXL345 accelerometer and an LM393 voltage monitoring chip, wherein the preset vibration threshold of the ADXL345 is 20 m / s². 2 The LM393 has a preset minimum voltage of 3.0V and a preset maximum voltage of 3.6V. The curing drive component is a PT100 heating element, and the epoxy containment chamber contains E-51 epoxy resin and T-31 curing agent. When the equipment is disassembled, a speed of 25m / s is generated. 2When the sensor component vibrates, or when the power supply voltage drops to 2.8V and rises to 3.8V, the sensor component sends a trigger signal to the curing drive component. The PT100 heating element starts and heats the curing agent to 60°C. After the curing agent and epoxy resin are mixed, they expand and cure within 5 seconds, directly damaging the FM25V02 fuse storage chip and surrounding data transmission lines, thus completely eliminating the risk of the key being forcibly extracted from a physical perspective.
[0082] Furthermore, the transfer of equipment ownership shall be carried out in accordance with the following steps:
[0083] Step S21: The biometric verification component collects the original user's real-time fingerprint and iris data and generates the original user's real-time fusion feature value; the main control module calculates the similarity between the original user's real-time fusion feature value and the fusion feature value in the fuse storage chip. When the similarity is greater than or equal to the preset threshold S2, proceed to step S22.
[0084] Step S22: The password input component receives the security password entered by the original user and generates a password verification value; the main control module calls the pre-stored password baseline verification value W. ref When the password verification value is compared with the pre-stored password baseline verification value X ref If they are equal, proceed to step S23;
[0085] Step S23: The main control module receives the ID card number and mobile phone number input by the original user, calculates their hash values, and compares them with the pre-stored ID card number hash values and mobile phone number hash values. If they match, proceed to step S24.
[0086] Step S24: The main control module detects no abnormal signals in the epoxy self-destruct structure, and the impedance of the fuse storage chip's fuse circuit is within the preset range R1 to R2; the main control module temporarily activates the rewrite permission of the bio-fuse storage module, controls the bio-acquisition component to collect the new user's fingerprint and iris data and generate the new user's fusion feature value, erases the original fusion feature value and writes the new user's fusion feature value, and permanently closes the rewrite permission of the bio-fuse storage module.
[0087] In a specific embodiment, the change of equipment ownership is performed according to the following steps:
[0088] Step S21: The biometric verification component collects the original user's real-time fingerprint and iris data, generates the original user's real-time fused feature value, and its similarity with the fused feature value in the fuse memory chip is 96%, which is greater than the preset threshold S2 = 95%. Proceed to step S22.
[0089] Step S22: The password input component receives the security key mykeydevice2024 entered by the original user, generates a key verification value, and compares it with the pre-stored key verification value W. ref If consistent, proceed to step S23;
[0090] Step S23: The main control module receives the ID number "110101199001011234" and mobile phone number "13800138000" entered by the original user through the password input component, calculates their SHA-256 hash values respectively, compares them with the hash values pre-stored in the fuse storage chip, and if the results are consistent, proceed to step S24.
[0091] Step S24: The main control module detects no abnormal signals in the epoxy self-destruct structure, and the fuse circuit impedance of the fuse storage chip is 150Ω, which is within the preset range of R1=100Ω to R2=200Ω. Then, the rewrite permission of the biometric fuse storage module is temporarily activated, and the biometric acquisition component is controlled to collect the fingerprint and iris data of the new user and generate the new user fusion feature value. After erasing the original fusion feature value and writing the new user fusion feature value, the rewrite permission is permanently closed. By introducing offline verification of legal identity information, the ownership change process is ensured to be safe, controllable and strictly bound to a specific user, so as to prevent the device from being illegally misappropriated.
[0092] Furthermore, the main control module has a built-in verification failure counter; when any step in the three-factor authentication fails, the verification failure counter accumulates the number of failures; when the number of failures is greater than or equal to the preset trigger count, the main control module controls the biological circuit breaker storage module to enter a temporary lockout state; the temporary lockout duration meets the following requirements:
[0093]
[0094] Among them, t lock t0 is the temporary locking duration, n is the cumulative number of failures, and n1 is the preset number of times the temporary lock is triggered.
[0095] In the temporary latched state, the three-factor authentication unit does not respond to any authentication requests, and the temporary latching duration does not exceed the preset maximum duration t. max .
[0096] In a specific embodiment, the main control module STM32L476RG has a built-in verification failure counter. The basic latching duration is set to t0 = 10 minutes, the preset number of times temporary locking is triggered is n1 = 3 times, and the preset maximum duration is t. max =2 hours. When the cumulative number of failures in three-factor validation is n=4, the temporary latching duration is t. lock =10×2( 4-3 ) = 20 minutes; when n = 5, t lock =10×2( 5-3 ) = 40 minutes; when n = 8, t lock =10×2( 8-3 ) = 320 minutes, at this point, because 320 minutes exceeds t max=120 minutes, the lockout duration is set to 120 minutes. In the temporary lockout state, the three-factor authentication unit does not respond to any authentication requests, effectively slowing down the brute-force attack and reducing the probability of the key being cracked.
[0097] Furthermore, the fuse memory chip is divided into a feature storage area and a key storage area; the feature storage area stores bio-fusion feature values, and the key storage area stores encryption key data, with encryption satisfying:
[0098]
[0099] Among them, K enc The encrypted key data, where K is the original key and IV is the encrypted key data. k Let V be the initialization vector for key encryption, E represent the symmetric encryption algorithm, and V be the initialization vector for key encryption. fusion For the biological fusion feature values in the feature storage area, This represents the XOR operation;
[0100] Read and write operations in the key storage area must first be compared with the fused feature value in the feature storage area. Only after the comparison is successful can the read and write operations be performed. If the comparison fails, the key storage area remains locked.
[0101] In a specific embodiment, the fuse memory chip FM25V02 is divided into a 1KB feature storage area and a 4KB key storage area. The feature storage area stores the biofusion feature value V. fusion Let the original key K be abcded1234567890, and the key encryption initialization vector IV be... k The value is 0987654321fedcba. First, calculate... We get a3c5e72143658709, then V fusion Using the key, the encrypted key data K is obtained by processing it with the AES-256 symmetric encryption algorithm E. enc The value is 2a4c6e8013579bdf3c5e7g9124680acb. When reading or writing operations are required in the key storage area, the fused feature value in the feature storage area must be compared first. The operation can only be performed if the comparison pass rate is above 90%. Otherwise, the key storage area remains locked, realizing the association protection between biometric features and keys and improving the security of key storage.
[0102] Furthermore, the epoxy self-destruct structure also includes an emergency trigger component; the emergency trigger component is electrically connected to the main control module; when the number of three-factor verification failures is greater than or equal to the preset emergency count, and the preset emergency count is greater than the preset trigger count, the main control module sends an emergency signal to the emergency trigger component; after receiving the emergency signal, the emergency trigger component directly controls the curing drive component to start the epoxy curing process, without waiting for the sensor component's detection results; the preset emergency count is the hardware curing parameter at the time of the equipment's manufacture.
[0103] In a specific embodiment, the emergency triggering component of the epoxy self-destruct structure is an NPN transistor, which is electrically connected to the GPIO port of the main control module. The device is factory-installed with a preset emergency count of 5, which is greater than the preset trigger count of 3. When the cumulative failure count of three-factor authentication n=5, the main control module sends a high-level emergency signal to the emergency triggering component. After the transistor is turned on, it directly supplies power to the PT100 heating element of the curing drive component. Without waiting for the detection results of the sensor component, the PT100 immediately heats the curing agent, completing the epoxy expansion curing within 10 seconds and destroying the bio-fuse storage module. This rapid response to serious hacking attempts minimizes the risk of key leakage.
[0104] Furthermore, a method for controlling a key storage device includes the following steps:
[0105] Step S31: Device initialization, the optical isolation offline text recognition module encrypts text information and transmits it to the main control module, and / or receives external data through the data communication interface and encrypts and transmits it to the main control module, the main control module generates encryption key data and stores it;
[0106] Step S32: Upon initial activation, the bio-acquisition component generates user fusion feature values and writes them into the fuse storage chip, triggering the rewrite circuit to blow.
[0107] Step S33: Key retrieval. After the three-factor authentication unit completes biometric comparison, dynamic password verification and physical key detection, the main control module decrypts and obtains the original key.
[0108] Step S34: Data output, the main control module sends the original key to the external device through the data communication interface;
[0109] Step S35: Anti-disassembly protection: When the sensor assembly detects abnormal vibration or voltage, it triggers the epoxy-cured damaged biological fuse storage module.
[0110] Step S36: Ownership change. After verifying the original user's identity and device status, write the new user's fusion feature value.
[0111] In a specific embodiment, the control method for the key storage device is applied to the aforementioned key storage device.
[0112] Step S31: During device initialization, the OV7670 optical component of the optically isolated offline text recognition module and the Tesseract OCR engine collect the mnemonic phrase "securekey888", encrypt it, and transmit it to the main control module STM32L476RG. The main control module generates and stores the encryption key data. At the same time, the user can also choose to import the contents of the key file "wallet.dat" generated on the computer into the device via the USB interface.
[0113] Step S32: Upon initial activation, the AS608 fingerprint module and IRIS-200 iris module collect the user's biological data, generate a fused feature value, and write it into the FM25VO2 fuse storage chip, triggering the rewrite circuit to blow.
[0114] Step S33: When the key is invoked, the three-factor authentication unit sequentially completes biometric comparison, dynamic password verification and 5-second physical key press detection, and the main control module decrypts to obtain the original key;
[0115] Step S34: When outputting data, the main control module sends the decrypted original key to the connected mobile app via the USB interface, and the user can copy and use it with one click in the app;
[0116] Step S35: During anti-disassembly protection, the ADXL345 sensor assembly detects 22 m / s. 2 Vibration triggered the epoxy curing process, damaging the bio-fuse storage module.
[0117] Step S36: When ownership changes, after verifying the original user's identity and device status, the new user's fused feature value is written. This method covers the entire device lifecycle and achieves secure and convenient data interaction and strict ownership management, ensuring key security at every stage.
[0118] The specific embodiments of the present invention have been described in detail above, but they are merely examples, and the present invention is not equivalent to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions to the present invention are also within the scope of the present invention. Therefore, all equivalent transformations and modifications made without departing from the spirit and scope of the present invention should be covered within the scope of the present invention.
Claims
1. A key storage device, characterized by, The application relates to a secure data storage device, which comprises an optical isolation offline character recognition module, a biological fuse storage module, a three-factor verification unit, an epoxy self-destruction structure, a data communication interface and a main control module, wherein the optical isolation offline character recognition module, the biological fuse storage module, the three-factor verification unit, the epoxy self-destruction structure and the data communication interface are electrically connected with the main control module; the optical isolation offline character recognition module collects external text information and converts the text information into encrypted data which is transmitted to the main control module; the data communication interface is used for connecting with external equipment, receiving external data or sending stored data; after receiving a first activation signal, the biological fuse storage module writes user fingerprint and iris data and permanently fuses and rewrites a circuit; the three-factor verification unit receives external multi-dimensional verification information and generates a verification signal which is transmitted to the main control module; the main control module controls the biological fuse storage module to output key data or keep locking according to the verification signal; the epoxy self-destruction structure monitors equipment dismounting intention and generates a state signal; when an abnormal signal is generated, the epoxy self-destruction structure expands, solidifies and destroys the biological fuse storage module.
2. The key storage device of claim 1, wherein, The optical isolation offline character recognition module is internally provided with an OCR engine and an image processing unit, and is electrically isolated from the main control module by physical separation; when the module collects external text information, a text image is acquired through an optical assembly; the image processing unit pre-processes and corrects the text image, and then the text image is converted into text data by the OCR engine; the text data is encrypted to obtain encrypted text data; the encrypted text data is sent to the main control module through a one-way transmission channel; the encryption satisfies the following formula: F (x) = x + k, wherein x represents the text data, F (x) represents the encrypted text data, and k represents a random number. where T enc is the encrypted text data, T is the original text data converted by the OCR engine, H represents the hash algorithm, IV is the text encryption initial vector, represents the XOR operation.
3. A key storage device according to claim 2, wherein, The biological fuse storage module comprises a biological collection assembly and a fuse storage chip, and the biological collection assembly is electrically connected with the fuse storage chip; when activated for the first time, the biological collection assembly collects user fingerprint and iris data, converts the data into feature vectors respectively, and generates fusion feature values, which satisfy the following formula: F (x, y) = x + y, wherein x represents the feature vector of the fingerprint, y represents the feature vector of the iris, and F (x, y) represents the fusion feature value. wherein, V fusion is a biological fusion feature value, V f is a fingerprint feature vector, V i is an iris feature vector, H represents a hash algorithm, represents an XOR operation; After the fusion feature value is written into the fuse storage chip, the rewriting circuit is permanently fused, and only reading operation is allowed, and the written fusion feature value cannot be modified or erased.
4. The key storage device of claim 3, wherein, The three-factor verification unit comprises a biological verification assembly, a password input assembly and a physical key assembly, and the biological verification assembly, the password input assembly and the physical key assembly are electrically connected with the main control module; verification is performed according to the following steps: Step S11: the biological verification assembly collects real-time fingerprint and iris data, converts the data into real-time feature vectors, and generates real-time fusion feature values, which satisfy the following formula: F (x, y) = x + y, wherein x represents the feature vector of the fingerprint, y represents the feature vector of the iris, and F (x, y) represents the fusion feature value. V′ fusion is a real-time biological fusion feature value, V′ f is a real-time fingerprint feature vector, V′ i is a real-time iris feature vector, H represents a hash algorithm, represents an XOR operation; the main control module calls the fusion feature value in the fuse storage chip, calculates the similarity between the real-time biological fusion feature value and the fusion feature value in the fuse storage chip, and when the similarity between the real-time biological fusion feature value and the fusion feature value in the fuse storage chip is greater than or equal to a preset threshold S1, step S12 is entered. Step S12: the password input assembly receives a 6-digit dynamic password and generates a password check value, which satisfies the following formula: F (x) = x + k, wherein x represents the password check value, F (x) represents the encrypted password check value, and k represents a random number. Wherein, P check is a password check value, P is a 6-bit dynamic password, T is a current verification timestamp, H represents a hash algorithm, represents an exclusive or operation; The main control module calls the pre-stored password reference check value P ref When the password check value is equal to the pre-stored password reference check value, step S13 is entered. Step S13: the physical key assembly receives a pressing operation, monitors the pressing duration t, and when t is greater than or equal to 3 seconds, sends a verification pass signal to the main control module; after receiving the signal, the main control module generates a control signal which allows the biological fuse storage module to output key data.
5. A key storage device according to claim 4, wherein, The epoxy self-destruction structure comprises a sensor assembly, a curing driving assembly and an epoxy containing cavity; the sensor assembly is electrically connected with the curing driving assembly, and the curing driving assembly is physically connected with the epoxy containing cavity; the sensor assembly detects the equipment vibration acceleration and the power supply voltage in real time, and sends a trigger signal to the curing driving assembly when the equipment vibration acceleration is greater than or equal to a preset vibration threshold, the power supply voltage is less than a preset minimum voltage or the power supply voltage is greater than a preset maximum voltage; after the curing driving assembly receives the trigger signal, the heating element is started to heat the curing agent in the epoxy containing cavity, and the curing agent expands and solidifies after mixing with the epoxy, thereby damaging the storage chip and the data transmission line of the biological fuse storage module.
6. A key storage device according to claim 5, wherein, The device ownership change is performed according to the following steps: Step S21: The biometric verification assembly collects the real-time fingerprint and iris data of the original user, and generates real-time fusion feature values of the original user; The main control module calculates the similarity of the real-time fusion feature values of the original user and the fusion feature values in the fuse storage chip, and when the similarity is greater than or equal to a preset threshold S2, step S22 is entered; Step S22: The password input assembly receives the security password input by the original user, and generates a password verification value; The main control module calls the pre-stored cipher reference check value W ref When the cipher check value is equal to the pre-stored cipher reference check value W ref Step S23 is entered. Step S23: The main control module receives the ID number and mobile phone number input by the original user, calculates the hash values thereof, and compares them with the pre-stored ID number hash value and mobile phone number hash value, and when they are consistent, step S24 is entered; Step S24: The main control module detects that the epoxy self-destruction structure has no abnormal signal, and the impedance of the fuse circuit of the fuse storage chip is within a preset range R1 to R2; the main control module temporarily activates the rewriting permission of the biological fuse storage module, controls the biological collection assembly to collect the fingerprint and iris data of the new user and generates new user fusion feature values, erases the original fusion feature values and writes the new user fusion feature values, and permanently closes the rewriting permission of the biological fuse storage module.
7. A key storage device according to claim 6, wherein, The main control module is provided with a verification failure counter; when any step in the three-factor verification fails, the verification failure counter accumulates the number of failures; when the number of failures is greater than or equal to a preset trigger number, the main control module controls the biological fuse storage module to enter a temporary locked state; the temporary locking duration satisfies: Wherein, t lock is a temporary locking duration, t0 is a basic locking duration, n is a cumulative failure number, and n1 is a preset number of times triggering temporary locking. In the temporary locking state, the three-factor verification unit does not respond to any verification request, and the temporary locking duration does not exceed a preset maximum duration t max .
8. The key storage device of claim 7, wherein, The fuse storage chip is divided into a feature storage area and a key storage area; the feature storage area stores biological fusion feature values, and the key storage area stores encrypted key data, which satisfies: wherein K enc is encrypted key data, K is an original key, IV k is a key encryption initial vector, E denotes a symmetric encryption algorithm, V fusion is a biometric fusion feature value of a feature storage area, denotes an exclusive OR operation; The read and write operations of the key storage area need to be compared with the fusion feature values of the feature storage area first, and only after the comparison is passed can the read and write operations be performed, and if the comparison fails, the key storage area remains locked.
9. A key storage device according to claim 8, characterized in that The epoxy self-destruction structure further comprises an emergency trigger assembly; the emergency trigger assembly is electrically connected with the main control module; when the number of three-factor verification failures is greater than or equal to a preset emergency number, and the preset emergency number is greater than the preset trigger number, the main control module sends an emergency signal to the emergency trigger assembly; After the emergency trigger assembly receives the emergency signal, it directly controls the curing driving assembly to start the epoxy curing process without waiting for the detection result of the sensor assembly; the preset emergency number is a hardware curing parameter when the device is shipped.
10. A control method of a key storage device, for the key storage device of any one of claims 1-9, comprising the following steps: Step S31: device initialization, the optical isolation offline character recognition module encrypts the mnemonic information and transmits to the main control module, and / or receives external data through the data communication interface and encrypts and transmits to the main control module, and the main control module generates encrypted key data and stores; Step S32: first activation, the biological collection component generates user fusion characteristic value and writes into the fuse storage chip, and triggers the fuse of the rewrite circuit; Step S33: key calling, after the three-factor verification unit completes the biological characteristic comparison, dynamic password check and physical key detection, the main control module decrypts to obtain the original key; Step S34: data output, the main control module sends the original key to the external device through the data communication interface; Step S35: anti-disassembly protection, when the sensor component detects abnormal vibration or voltage, the epoxy curing destroys the biological fuse storage module; Step S36: ownership change, after verifying the original user identity and device state, write the new user fusion characteristic value.