Content update authentication method and apparatus

Abstract

The application relates to the technical field of digital information transmission, and provides a content updating authentication method and device, which comprises the following steps: a card seat sends an instruction to an electronic paper card and receives a UID, the UID is the identification of a built-in MCU of the electronic paper card; a first preset key corresponding to the UID and to-be-updated content data are acquired, a random challenge number is generated, and a response value calculated by the electronic paper card according to a second preset key, the UID and the random challenge number is received; after the response value is verified, a first session key is derived according to the UID, the random challenge number and the first preset key, encrypted to-be-updated content data is obtained to obtain encrypted content data, and the encrypted content data is sent; the electronic paper card derives a second session key according to the UID, the random challenge number and the second preset key, decrypts to obtain the to-be-updated content data, and refreshes the display content of the electronic paper card. Based on the application scheme, reliable and low-cost security authentication can be realized in the content updating process of the electronic paper card.

Description

Technical Field

[0001] This application relates to the field of digital information transmission technology, and in particular to a content update authentication method and apparatus. Background Technology

[0002] Electronic paper cards are portable devices utilizing electronic ink display technology. Due to their low power consumption, thinness, and good sunlight visibility, they are commonly used in various scenarios such as commemorative cards, identity verification, electronic price tags, and access control cards. In practical applications, electronic paper cards typically require external reading and writing devices for content updates. However, due to limitations in device identification and data protection within existing update mechanisms, there is a risk of unauthorized data access or tampering during the content update process, negatively impacting the confidentiality of the data on the card and the copyright protection of related digital content. Therefore, achieving reliable and low-cost secure authentication during the content update process of electronic paper cards has become an urgent problem to be solved. Summary of the Invention

[0003] This application provides a content update authentication method and apparatus to solve the technical problem of how to achieve reliable and low-cost secure authentication during the content update process of electronic paper cards.

[0004] In a first aspect, embodiments of this application provide a content update authentication method applied to a card slot. The content update authentication method includes: When the card slot and the electronic paper card are in a contact communication connection, a UID reading command is sent to the electronic paper card; Receive the UID sent by the electronic paper card according to the UID reading command. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. Obtain the first preset key and the content data to be updated corresponding to the UID; Generate and send a random challenge number to the electronic paper card, and receive the response value sent by the electronic paper card. The response value is calculated by the electronic paper card based on the second preset key, UID and random challenge number. The response value is verified based on the first preset key, UID, and random challenge number to obtain the verification result; If the verification result indicates that the verification is successful, the first session key is derived based on the UID, the random challenge number and the first preset key, and the content data to be updated is encrypted based on the first session key to obtain the encrypted content data; Send encrypted content data to the e-paper card so that the e-paper card can update its content based on the encrypted content data.

[0005] In conjunction with the first aspect, in some possible implementations, the first preset key corresponding to the UID and the content data to be updated are obtained, including any one of the following: Send the UID to the server and receive the first preset key corresponding to the UID and the content data to be updated from the server. Read the first preset key corresponding to the UID and the content data to be updated stored locally in the card slot.

[0006] Combining the first aspect and the above implementation methods, in some possible implementation methods, the response value is verified based on the first preset key, UID, and random challenge number to obtain the verification result, including: Based on the first preset key, UID, and random challenge number, the expected response value is calculated using a message authentication code algorithm, wherein the message authentication code algorithm is HMAC-SHA256 or AES-CMAC; The expected response value is compared with the actual response value to obtain the verification result.

[0007] Combining the first aspect and the above implementation methods, in some possible implementation methods, a first session key is derived based on the UID, the random challenge number, and the first preset key, and the content data to be updated is encrypted using the first session key to obtain encrypted content data, including: The first session key is obtained by performing derivation operations on the UID, random challenge number and first preset key using key derivation functions, wherein the key derivation functions include HKDF-SHA256; Using the first session key, the content data to be updated is encrypted in AES-CTR mode to obtain encrypted content data.

[0008] In combination with the first aspect and the above implementation methods, some possible implementation methods, after sending encrypted content data to the electronic paper card, also include: Receive the first update feedback message sent by the electronic paper card, which is sent by the electronic paper card after performing a content update based on the encrypted content data; Based on the first update feedback message, send the second update feedback message to the server; Both the first update feedback message and the second update feedback message are used to indicate whether the content update of the electronic paper card was successful.

[0009] Combining the first aspect and the above implementation methods, in some possible implementation methods, after verifying the response value based on the first preset key, UID, and random challenge number, and obtaining the verification result, the method further includes: If the verification result indicates that the verification failed, the first number of authentication failures is accumulated, and an authentication failure notification is sent to the electronic paper card. If the number of authentication failures reaches a preset first threshold, a lock notification is sent to the server, and the lock notification carries the UID.

[0010] Combining the first aspect and the above implementation methods, in some possible implementation methods, the content update authentication method also includes: In response to receiving an unlock trigger operation for a locked e-paper card, an unlock request is sent to the server, carrying the UID in the unlock request; Receive the unlock credential corresponding to the UID sent by the server when the unlock request meets the preset verification conditions; Send an unlock command carrying an unlock credential to the electronic paper card to unlock it.

[0011] Combining the first aspect and the above implementation methods, in some possible implementation methods, the content update authentication method also includes: Send a certificate reading command to the electronic paper card; Receive the content digital certificate sent by the electronic paper card; the content digital certificate is a digital certificate stored in the electronic paper card. Send a verification request to the server, which includes the UID and the content digital certificate. The server receives the copyright verification result in response to the verification request. The copyright verification result is used to indicate the authenticity of the copyright and / or ownership of the electronic paper card.

[0012] Secondly, embodiments of this application provide a content update authentication method applied to electronic paper cards, wherein the electronic paper card stores a second preset key, and the content update authentication method includes: When the card slot and the electronic paper card are in a contact communication connection, the card slot receives the UID reading command sent by the card slot; The UID of the electronic paper card is read according to the UID reading instruction, and the UID is sent to the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. Receive random challenge numbers sent by the card slot; Calculate the response value based on the second preset key, UID, and random challenge number, and send the response value to the card slot; The receiver card slot sends encrypted content data after the verification response value is passed; A second session key is derived based on the UID, the random challenge number, and the second preset key; The encrypted content data is decrypted using the second session key to obtain the content data to be updated; The display content of the e-paper card is refreshed based on the data to be updated.

[0013] In conjunction with the second aspect, some possible implementations, after refreshing the display content of the e-paper card based on the data to be updated, also include: Send a first update feedback message to the card slot. The first update feedback message is used to indicate whether the content update of the electronic paper card was successful. Enter static hold mode. Static hold mode is used to keep the refreshed display content displayed after the electronic paper card is powered off.

[0014] Combining the second aspect and the above implementation methods, in some possible implementations, the content update authentication method also includes: The receiver card slot sends an authentication failure notification after the verification response value fails. Based on the authentication failure notification, accumulate the number of second authentication failures; If the number of second authentication failures reaches a preset second threshold, the electronic paper card is locked. The locked state is used to prevent the electronic paper card from responding to any commands other than the unlock command.

[0015] In conjunction with the second aspect and the above implementation methods, in some possible implementations, when the electronic paper card is in a locked state, the content update authentication method also includes: Receive the unlock command sent by the card slot, which carries the unlock credentials; Verify the unlocking credentials carried in the unlocking command; Once the unlocking credential verification is successful, the electronic paper card will be unlocked.

[0016] In conjunction with the second aspect and the above implementation methods, in some possible implementations, the electronic paper card also stores a content digital certificate; the content update authentication method also includes: Receive certificate read command sent by the card slot; According to the certificate reading instruction, the stored content digital certificate is read and sent to the card slot.

[0017] Thirdly, embodiments of this application provide a content update authentication method, applied to a server, the content update authentication method including: The receiver sends the UID of the electronic paper card to the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. Based on the UID, determine the first preset key and the content data to be updated corresponding to the UID; Send the first preset key and the content data to be updated to the card slot.

[0018] In conjunction with the third aspect, in some possible implementations, after sending the first preset key and the content data to be updated to the card slot, the following is also included: The receiver sends a second update feedback message, which indicates whether the content update of the electronic paper card was successful.

[0019] In conjunction with the third aspect and the above implementation methods, some possible implementation methods for content update authentication also include: Receive a lock notification sent by the card slot. The lock notification is sent by the card slot when the number of first authentication failures reaches a preset first threshold, and the lock notification carries a UID. Based on the lock notification, the e-paper card corresponding to the UID is marked as locked.

[0020] In conjunction with the third aspect and the above implementation methods, some possible implementation methods for content update authentication also include: Receive the unlock request sent by the card slot, the unlock request carries the UID; If the unlock request meets the preset verification conditions, an unlock credential corresponding to the UID is sent to the card slot, so that the card slot sends an unlock command carrying the unlock credential to the electronic paper card.

[0021] In conjunction with the third aspect and the above implementation methods, some possible implementation methods for content update authentication also include: The card slot receives a verification request, which carries a UID and a content digital certificate. The content digital certificate is a digital certificate that the card slot reads from the electronic paper card. Based on the UID, query the registered digital certificate corresponding to the UID. The registered digital certificate is a pre-registered and stored digital certificate. The content digital certificate is compared with the registered digital certificate to obtain the copyright verification result; Send the copyright verification result to the card slot. The copyright verification result is used to indicate the authenticity of the copyright and / or ownership of the electronic paper card.

[0022] Fourthly, embodiments of this application provide a first content update authentication device. Applied to card slots, the first content update authentication device includes: The first sending module is used to send a UID reading command to the electronic paper card when the card slot and the electronic paper card are in a contact communication connection. The first receiving module is used to receive the UID sent by the electronic paper card according to the UID reading instruction. The UID is an identifier that is fixed at the factory by the MCU built into the electronic paper card and cannot be rewritten. The acquisition module is used to acquire the first preset key corresponding to the UID and the content data to be updated; The transceiver module is used to generate and send random challenge numbers to the electronic paper card, and to receive response values ​​sent by the electronic paper card. The response values ​​are calculated by the electronic paper card based on the second preset key, UID, and random challenge number. The verification module is used to verify the response value based on the first preset key, UID, and random challenge number, and obtain the verification result; The encryption module is used to derive a first session key based on the UID, random challenge number and first preset key when the verification result indicates that the verification is successful, and to encrypt the content data to be updated based on the first session key to obtain encrypted content data. The second sending module is used to send encrypted content data to the electronic paper card so that the electronic paper card can update its content based on the encrypted content data.

[0023] Fifthly, embodiments of this application provide a second content update authentication device applied to an electronic paper card, the electronic paper card storing a second preset key, the second content update authentication device comprising: The second receiving module is used to receive the UID reading command sent by the card slot when the card slot and the electronic paper card are in contact communication connection. The reading module is used to read the UID of the electronic paper card according to the UID reading instruction and send the UID to the card slot. The UID is an identifier that is factory-fixed by the MCU built into the electronic paper card and cannot be rewritten. The third receiving module is used to receive the random challenge numbers sent by the card slot; The calculation module is used to calculate the response value based on the second preset key, UID and random challenge number, and send the response value to the card slot; The fourth receiving module is used to receive encrypted content data sent by the card slot after the verification response value is passed; The derivation module is used to derive a second session key based on the UID, the random challenge number, and the second preset key; The decryption module is used to decrypt the encrypted content data based on the second session key to obtain the content data to be updated; The refresh module is used to refresh the displayed content of the e-paper card based on the data to be updated.

[0024] Sixthly, embodiments of this application provide a third content update authentication device, applied to a server, the third content update authentication device comprising: The receiving module is used to receive the UID of the electronic paper card sent by the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. The determination module is used to determine the first preset key and the content data to be updated corresponding to the UID based on the UID; The sending module is used to send the first preset key and the content data to be updated to the card slot.

[0025] The content update authentication method and apparatus provided in this application utilize the UID (User ID) embedded in the electronic paper card's MCU, which is factory-fixed and cannot be rewritten, as an immutable device identity credential. This UID, combined with a random challenge number and a preset key, is used to calculate and verify the response value, thus achieving device identity legitimacy verification between the card holder and the electronic paper card. This effectively prevents unauthorized devices from accessing the electronic paper card's data. Furthermore, after successful verification, both parties derive session keys based on the UID, random challenge number, and preset key. These session keys are used to encrypt and decrypt the content data to be updated during transmission, ensuring the confidentiality and integrity of the content update data during contactless communication. Moreover, the above authentication and encryption processes rely entirely on the MCU and preset key embedded in the electronic paper card, eliminating the need for additional hardware authentication components. This achieves reliable and low-cost secure authentication during the content update process of the electronic paper card. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a flowchart illustrating a content update authentication method provided in an embodiment of this application; Figure 2 This is a flowchart illustrating another content update authentication method provided in an embodiment of this application; Figure 3 This is a flowchart illustrating another content update authentication method provided in an embodiment of this application; Figure 4 This is a schematic diagram of the interaction flow of a content update authentication method provided in an embodiment of this application; Figure 5 This is a schematic diagram of the interaction flow of another content update authentication method provided in an embodiment of this application; Figure 6 This is a schematic diagram of the structure of a first content update authentication device provided in an embodiment of this application; Figure 7 This is a schematic diagram of the structure of a second content update authentication device provided in an embodiment of this application; Figure 8 This is a schematic diagram of the structure of a third content update authentication device provided in an embodiment of this application. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] The following is a bilingual explanation of some of the terms used in this application: Unique Identifier (UID); Microcontroller Unit (MCU); Hash-based Message Authentication Code (HMAC); Secure Hash Algorithm (SHA); Advanced Encryption Standard (AES); Cipher-based Message Authentication Code (CMAC); Counter mode (CTR); HMAC-based Extract-and-Expand KeyDerivation Function (HKDF).

[0030] Electronic paper cards are portable devices that utilize electronic ink display technology. Due to their low power consumption, thinness, and good sunlight visibility, they are commonly used in various scenarios such as commemorative cards, identity verification, electronic price tags, and access control cards. In practical applications, electronic paper cards typically require external reading and writing devices for content updates.

[0031] In some related technologies, external readers typically send the data to be updated directly to the e-paper card to update the content. For example, after detecting the e-paper card's access, the external reader directly reads the data stored in the e-paper card, or writes the data to be updated into the e-paper card in plaintext. During this process, no secure authentication of the device identity is performed between the external reader and the e-paper card. In another possible implementation, the e-paper card has a built-in security chip, and the external reader interacts with this security chip to complete the content update.

[0032] It is evident that the relevant technology has several shortcomings: Firstly, the lack of a device authentication mechanism between external reading / writing devices and electronic paper cards allows any external reading / writing device to read and write data on the electronic paper cards, posing a risk of unauthorized data access. Secondly, the data is transmitted in plaintext during content updates, making it susceptible to eavesdropping or tampering, thus compromising data confidentiality and integrity. Thirdly, the method of updating content through a built-in security chip increases the hardware cost of electronic paper cards, making it difficult to widely apply in cost-sensitive scenarios.

[0033] Therefore, how to achieve reliable and low-cost secure authentication during the content update process of electronic paper cards has become an urgent problem to be solved.

[0034] To address the aforementioned issues, the solution provided in this application mainly includes: when the card slot and the electronic paper card are in a contact communication connection, the card slot sends a UID read command to the electronic paper card; after receiving the UID read command, the electronic paper card reads its built-in MCU's factory-fixed and unrewritable identifier, i.e., the UID, and sends it to the card slot; the card slot receives the UID and obtains the first preset key and the content data to be updated corresponding to the UID; subsequently, the card slot generates and sends a random challenge number to the electronic paper card; after receiving the random challenge number, the electronic paper card calculates a response value based on its stored second preset key, UID, and random challenge number and sends it to the card slot; the card slot receives the response value. The system verifies the response value based on the first preset key, UID, and random challenge number to obtain a verification result. If the verification result indicates that the verification is successful, the card slot derives a first session key based on the UID, random challenge number, and first preset key, and encrypts the content data to be updated based on the first session key. After obtaining the encrypted content data, the card slot sends it to the electronic paper card. After receiving the encrypted content data, the electronic paper card derives a second session key based on the UID, random challenge number, and second preset key, and decrypts the encrypted content data based on the second session key to obtain the content data to be updated. Then, the electronic paper card refreshes its display content based on the content data to be updated. Based on the above process, by utilizing the UID (Unique Identifier) ​​embedded in the electronic paper card's MCU (Microcontroller Unit) as an immutable device identity credential, and combining it with a random challenge number and a preset key to calculate and verify the response value, the device identity legitimacy verification between the card holder and the electronic paper card is achieved, effectively preventing unauthorized devices from accessing the electronic paper card's data. Simultaneously, after successful verification, both parties derive session keys based on the UID, random challenge number, and preset key, and use these session keys to encrypt and decrypt the content data to be updated during transmission, ensuring the confidentiality and integrity of the content update data during the contactless communication connection. Furthermore, the above authentication and encryption processes are all completed using the MCU and preset key embedded in the electronic paper card, eliminating the need for additional hardware authentication components, thus achieving reliable and low-cost secure authentication during the content update process of the electronic paper card.

[0035] Furthermore, compared to the mechanism of directly transmitting data in plaintext in related technologies, the embodiments of this application use a session key derived from a UID to encrypt and transmit the content data to be updated. In this process, the above authentication and encryption operations are all completed by the MCU built into the electronic paper card, without the need for additional hardware authentication components such as security chips, adding only a very low MCU cost in terms of hardware; at the same time, by introducing a copyright verification mechanism for digital content certificates, it can meet the protection needs of protecting the displayed image content from tampering and tracing copyright ownership in a large number of application scenarios, thereby significantly improving the system's security protection capabilities and commercial added value while achieving low-cost security authentication.

[0036] The following describes several entities involved in the embodiments of this application: Card slot: An external read / write device with data processing and communication capabilities, configured to interact with electronic paper cards to achieve data reading, writing and authentication; specifically, it can be implemented as a dedicated read / write device including a microcontroller and physical contacts, or as a terminal device including a wireless communication module and interacting with a server, and the embodiments of this application do not limit it.

[0037] Electronic paper card: A portable device that utilizes electronic ink display technology and has data storage and processing capabilities, configured to display updated content and participate in the authentication process; specifically, it can be implemented as a card-shaped electronic device with a built-in microcontroller, electronic paper display screen and non-volatile memory, or it can be implemented as a smart card device that includes gold finger contacts and communicates with external devices through physical contact. The embodiments of this application do not limit this.

[0038] Server-side: A data processing platform with data storage, management and communication capabilities, configured to provide data query, content distribution and authorization management services; specifically, it can be implemented as a cloud server, a local server or a distributed cluster server, and the embodiments of this application do not limit it.

[0039] The following is a preliminary introduction to the connections between multiple entities: Between the card holder and the electronic paper card: a contact communication connection is established for data transmission and command interaction; specifically, it can be implemented as a serial peripheral interface connection established through gold finger contacts or spring pin contacts, but this application embodiment does not limit this.

[0040] Between the card slot and the server: a network communication connection is configured to be established for data synchronization and remote command interaction; specifically, it can be implemented as a network connection established through a wireless fidelity network or a wired Ethernet network, and this application embodiment does not limit this.

[0041] It should be further noted that in scenarios such as bulk card issuance, there may be an architecture where a hub control device communicates with multiple card slots, and each card slot communicates with an electronic paper card. In this architecture, the hub control device can address and control multiple card slots through a bus mechanism and independent chip select signals, enabling each card slot to independently perform authentication and data interaction processes with its connected electronic paper card. This scenario does not exceed the definition of card slots, electronic paper cards, and their corresponding methods in the embodiments of this application. That is, the description of the interaction between card slots and electronic paper cards in the subsequent embodiments of this application already covers such scenarios of multiple card slots operating in parallel, and will not be repeated here.

[0042] The content update authentication method provided in the embodiments of this application will be described in detail below.

[0043] Please see Figure 1 , Figure 1 This is a flowchart illustrating a content update authentication method provided in an embodiment of this application. Figure 1 As shown, the method of this application embodiment is applied to a card holder and may include the following steps S101~S107: S101, when the card slot and the electronic paper card are in contact communication connection, send a UID reading command to the electronic paper card; S102, receive the UID sent by the electronic paper card according to the UID reading instruction. The UID is the identifier that is fixed in the factory by the MCU built into the electronic paper card and cannot be rewritten. S103, Obtain the first preset key and content data to be updated corresponding to the UID; S104, Generate and send a random challenge number to the electronic paper card, and receive the response value sent by the electronic paper card. The response value is calculated by the electronic paper card based on the second preset key, UID and random challenge number; S105, verify the response value based on the first preset key, UID and random challenge number to obtain the verification result; S106, if the verification result indicates that the verification is successful, derive the first session key based on the UID, the random challenge number and the first preset key, and encrypt the content data to be updated based on the first session key to obtain encrypted content data; S107, send encrypted content data to the electronic paper card so that the electronic paper card can update its content based on the encrypted content data.

[0044] Specifically, the first step is to send a UID read command to the electronic paper card when the card slot and the electronic paper card are in a contact communication connection. Here, a contact communication connection refers to a communication connection established through physical contact, such as a serial peripheral interface connection implemented through metal contacts; the UID read command is a control command used to request the reading of the UID of a specified hardware component in the electronic paper card, which in this embodiment is represented by an MCU.

[0045] Regarding this step, in some possible implementations, after the card slot detects that a contact communication connection has been established with the electronic paper card, a UID read instruction can be encapsulated and sent to the electronic paper card through a serial peripheral interface bus according to a preset communication frame format.

[0046] Furthermore, the system receives the UID sent by the electronic paper card according to the UID reading command. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. Here, UID refers to the unique identifier of the device, such as the hardware serial number fixed and unrewritable by the MCU at the factory; MCU refers to the microcontroller unit, which is a chip that integrates a processor, memory, and input / output interfaces.

[0047] Regarding this step, in some possible implementations, after the electronic paper card receives the UID read instruction and reads the identifier that is factory-fixed and cannot be rewritten by its built-in MCU, the card slot receives the data frame returned by the electronic paper card through the serial peripheral interface bus and parses the UID from the data frame.

[0048] Further, the system obtains the first preset key corresponding to the UID and the content data to be updated. The first preset key refers to pre-stored encrypted data used for authentication; the content data to be updated refers to image data or other types of multimedia data used to update the display interface.

[0049] Regarding this step, in some possible implementations, the methods for obtaining the first preset key and the content data to be updated corresponding to the UID can include local acquisition and remote acquisition. Specifically, the card slot can query the local secure storage area using the UID as an index to read the first preset key and the content data to be updated corresponding to the UID; alternatively, the card slot can also send an acquisition request carrying the UID to the server via a network communication link, and receive the first preset key and the content data to be updated corresponding to the UID from the server based on the acquisition request.

[0050] Furthermore, a random challenge number is generated and sent to the electronic paper card, and a response value is received from the electronic paper card. The response value is calculated by the electronic paper card based on the second preset key, the UID, and the random challenge number. Here, the random challenge number refers to a random value generated by a random number generator for the challenge-response authentication process; the response value refers to the calculation result based on the key and the challenge number used to prove the legitimacy of the identity; and the second preset key refers to encrypted data pre-stored on the electronic paper card side for participating in the response value calculation.

[0051] Regarding this step, in some possible implementations, the card slot can call its built-in random number generator to generate a random challenge number, encapsulate the random challenge number as a data payload into an instruction frame, and send it to the electronic paper card via a contact communication connection. Subsequently, it can receive the response value returned by the electronic paper card. This response value is obtained by the electronic paper card calling its stored second preset key and combining it with the UID and the random challenge number.

[0052] Furthermore, the response value is verified based on the first preset key, UID, and random challenge number to obtain the verification result. Verification refers to the process of comparing the expected result with the actual received result to confirm its legitimacy; the verification result refers to the identification information used to indicate whether the verification passed.

[0053] Regarding this step, in some possible implementations, the card slot can take the first preset key, UID, and random challenge number as input parameters, use the message authentication code algorithm to generate the expected response value, and compare the expected response value with the response value received through the contact communication connection byte by byte, and output the verification result based on the consistency of the comparison.

[0054] It should be noted that the pairing relationship between the first and second preset keys varies depending on the key system used. In a symmetric key system, the second preset key corresponding to a legitimate e-paper card is the same as the first preset key of the card slot; if they are different, the expected response value calculated by the card slot will not match the response value calculated by the e-paper card, resulting in verification failure and indicating that the e-paper card is illegitimate. In an asymmetric key system, the first preset key is a public key, and the second preset key is a private key paired with this public key; the two are different. The card slot uses the first preset key to verify the response value generated by the e-paper card using the second preset key. If the verification passes, the e-paper card is legitimate; if the verification fails, the e-paper card is illegitimate.

[0055] Furthermore, if the verification result indicates successful verification, a first session key is derived based on the UID, random challenge number, and first preset key. The data to be updated is then encrypted using this first session key to obtain encrypted content data. Here, successful verification means the expected response value matches the received response value; derivation refers to the process of generating a new key from one or more input parameters using a key derivation function; the first session key is the temporary key used for encrypting data in this communication session; encryption refers to the process of converting plaintext data into ciphertext data using the key; and encrypted content data refers to the encrypted content data to be updated.

[0056] Regarding this step, in some possible implementations, if the verification result indicates that the verification is successful, the card holder can concatenate the UID and the random challenge number as input material, and use a key derivation function to perform derivation operations in combination with the first preset key to generate the first session key. Then, a symmetric encryption algorithm is called to perform encryption operations on the content data to be updated using the first session key as the encryption key, and output the encrypted content data.

[0057] Furthermore, encrypted content data is sent to the electronic paper card so that the electronic paper card can update its content based on the encrypted content data. Content update refers to the process of writing the received data into memory and driving the display screen to refresh its display.

[0058] Regarding this step, in some possible implementations, the card slot can use a contact communication connection to divide the encrypted content data into multiple data blocks and send them sequentially to the electronic paper card, so that the electronic paper card can receive the encrypted content data, decrypt it, and then perform content updates.

[0059] It should be noted that if the electronic paper card has other factory-fixed hardware identifiers that cannot be rewritten, such as the serial number fixed in the chip's internal register or the device code written by the fuse, then the hardware identifier can also replace the MCU's UID in this embodiment, that is, it can be used as the electronic paper card's identity credential to participate in response value calculation and the derivation of the first session key.

[0060] In this embodiment, the card holder obtains the UID (Unique Identifier) ​​embedded in the electronic paper card's MCU, which is factory-fixed and cannot be rewritten. It then verifies the response value calculated from the electronic paper card based on a first preset key, the UID, and a random challenge number. Upon successful verification, the card holder derives a first session key based on the UID, the random challenge number, and the first preset key. This first session key is then used to encrypt the content data to be updated, resulting in encrypted content data, which is then sent. This process, based on the electronic paper card's embedded MCU and preset key, completes identity authentication and data encryption without requiring additional hardware authentication components, ensuring data confidentiality and integrity during the content update process.

[0061] In one embodiment, the above step "obtaining the first preset key corresponding to the UID and the content data to be updated" can be further refined and may include the following steps: Send the UID to the server and receive the first preset key corresponding to the UID and the content data to be updated from the server. Read the first preset key corresponding to the UID and the content data to be updated stored locally in the card slot.

[0062] Specifically, on the one hand, it can send a UID to the server and receive the first preset key corresponding to the UID and the content data to be updated sent by the server.

[0063] Regarding this step, in some possible implementations, the card slot can encapsulate the parsed UID into a query request message and send it to the server via an established network communication connection. After receiving the query request message, the server performs a matching verification on the UID. If the verification is successful, it packages the first preset key corresponding to the UID and the content data to be updated into a response message and sends it to the card slot. The card slot receives and parses the response message to obtain the first preset key and the content data to be updated corresponding to the UID.

[0064] On the other hand, it can read the first preset key corresponding to the UID and the content data to be updated stored locally in the card slot. Here, local storage refers to using non-volatile storage media integrated inside the card slot, such as using a secure storage chip or read-only memory to store the first preset key corresponding to the UID and the content data to be updated.

[0065] Regarding this step, in some possible implementations, the card slot can use the parsed UID as a retrieval index to query a pre-set mapping table in the card slot's local storage, locate the table entry that matches the UID from the mapping table, and then extract the corresponding first pre-set key and the content data to be updated from the matching table entry.

[0066] It should be noted that this embodiment involves two implementation methods. When the card slot has network communication capabilities and is in a network coverage environment, the method of obtaining the first preset key and the content data to be updated from the server can be selected to obtain the latest data. When the card slot does not have network communication capabilities or is in an offline environment, the method of reading the local storage of the card slot can be selected to complete the content update authentication of the electronic paper card without relying on the network.

[0067] In this embodiment, by providing two methods for obtaining the first preset key and the content data to be updated corresponding to the UID—obtaining from the server and reading from the local storage of the card slot—the card slot can obtain the first preset key and the content data to be updated from the server when it has a network communication connection, and can read the corresponding first preset key and the content data to be updated from the local storage when there is no network communication connection. Thus, the first preset key and the content data to be updated can be obtained under different network conditions to perform subsequent verification and encryption processes.

[0068] In one embodiment, the step "verifying the response value based on the first preset key, UID, and random challenge number to obtain the verification result" can be further refined and may include the following steps: Based on the first preset key, UID, and random challenge number, the expected response value is calculated using a message authentication code algorithm, wherein the message authentication code algorithm is HMAC-SHA256 or AES-CMAC; The expected response value is compared with the actual response value to obtain the verification result.

[0069] Specifically, the expected response value is first calculated using a message authentication code algorithm based on the first preset key, UID, and random challenge number. The message authentication code algorithm can be either HMAC-SHA256 or AES-CMAC. Here, the message authentication code algorithm refers to the cryptographic operation used to verify data integrity and authenticity; the expected response value refers to the data calculated by the card slot based on its stored parameters and used as a comparison benchmark; HMAC-SHA256 refers to a message authentication code algorithm based on a hash function; and AES-CMAC refers to a message authentication code algorithm based on a block cipher.

[0070] Regarding this step, in some possible implementations, the cassette can use the first preset key as the key parameter, concatenate the UID and the random challenge number as input data, call the HMAC-SHA256 operation logic to process the input data, and use the output digest data as the expected response value. Alternatively, the cassette can use the first preset key as the symmetric key, combine the UID and the random challenge number into a data block, call the AES-CMAC operation logic to process the data block, and use the generated authentication tag data as the expected response value.

[0071] Optionally, additional data can be introduced into the message authentication code algorithm calculation. Specifically, the first preset key is used as the key parameter, and the UID, random challenge number, and additional data are concatenated into input data or combined into a data block. The expected response value is calculated using the message authentication code algorithm. The additional data includes at least one of session identifier, service type identifier, or timestamp to further improve the security entropy of the calculation result and enhance the ability to resist replay attacks. Correspondingly, the same additional data is used in the calculation of the response value on the electronic paper card side.

[0072] Furthermore, the expected response value is compared with the actual response value to obtain the verification result. Here, comparison refers to the operation of comparing two or more data sequences bit by bit or byte by byte.

[0073] Regarding this step, in some possible implementations, the card slot can compare the expected response value with the received response value byte by byte; if the expected response value and the response value are completely consistent, a verification result indicating that the verification has passed is obtained; if the expected response value and the response value are different, a verification result indicating that the verification has failed is obtained.

[0074] It should be further noted that, given the potential differences in the memory resources of the MCUs built into different electronic paper cards, this embodiment uses HMAC-SHA256 or AES-CMAC as the message authentication code algorithm. HMAC-SHA256 is suitable for MCUs with memory resources greater than or equal to the corresponding threshold to provide high security strength, while AES-CMAC is suitable for MCUs with memory resources less than the corresponding threshold to reduce computational resource consumption. Both algorithms can ensure that the calculation process of the expected response value is tamper-resistant, thereby providing cryptographic protection for the accuracy of the verification result and matching the low-cost and resource-constrained hardware characteristics of electronic paper cards.

[0075] Based on the same technical concept of generating an expected response value using a first preset key, UID, and random challenge number, and comparing it with the response value to confirm its legitimacy, other message authentication code algorithms with equivalent cryptographic security strength can also be applied to this embodiment to replace the specific algorithm mentioned above, which will not be elaborated here.

[0076] In this embodiment, the expected response value is obtained by using a message authentication code algorithm on the card holder side to calculate the first preset key, UID and random challenge number, and then comparing the expected response value with the response value. This allows the card holder to complete the authentication of the electronic paper card without transmitting the first preset key, thereby obtaining an accurate verification result and providing a security premise for the subsequent encrypted transmission of content data.

[0077] In one embodiment, the above step of "deriving a first session key based on the UID, the random challenge number, and the first preset key, and encrypting the content data to be updated based on the first session key to obtain encrypted content data" can be further refined and may include the following steps: The first session key is obtained by performing derivation operations on the UID, random challenge number and first preset key using key derivation functions, wherein the key derivation functions include HKDF-SHA256; Using the first session key, the content data to be updated is encrypted in AES-CTR mode to obtain encrypted content data.

[0078] Specifically, the first step is to use a key derivation function to perform derivation operations on the UID, random challenge number, and first preset key to obtain the first session key. The key derivation function includes HKDF-SHA256. Here, a key derivation function refers to a function that generates a new key from basic key materials using a specific cryptographic algorithm; derivation operation refers to the process of combining multiple input parameters and inputting them into the key derivation function to output a new key; HKDF-SHA256 refers to a secure hash algorithm key derivation function based on hash message authentication codes.

[0079] Regarding this step, in some possible implementations, the cassette holder can concatenate the UID and the random challenge number as input materials, and use a key derivation function to perform derivation operations in conjunction with a first preset key to generate a first session key. Specifically, the cassette holder can use the first preset key as the base key, and input the UID and the random challenge number as input materials into the key derivation function, which will then perform derivation operations and output a fixed-length first session key.

[0080] Furthermore, the first session key is used to encrypt the content data to be updated in AES-CTR mode, resulting in encrypted content data. AES-CTR mode refers to a block cipher operating mode that uses the Advanced Encryption Standard algorithm and performs data encryption in counter mode.

[0081] Regarding this step, in some possible implementations, after obtaining the first session key, the card slot can use it as a symmetric encryption key to encrypt the content data to be updated in AES-CTR mode, converting the content data into ciphertext to obtain encrypted content data. During this process, the card slot generates a counter sequence and encrypts it using the first session key to generate a keystream. Subsequently, the keystream is XORed with the content data to be updated, ultimately outputting the encrypted content data.

[0082] It should be further explained that this embodiment lists key derivation functions including HKDF-SHA256 and AES-CTR mode. Since the UID is unique and the random challenge number is random, HKDF-SHA256 can extract the security entropy of the UID and the random challenge number into the first session key, making the first session key random and unpredictable. At the same time, the AES-CTR mode can encrypt the content data to be updated without padding the complete data block, which reduces the computational overhead while ensuring the confidentiality of the encrypted content data, thus adapting to the hardware resource limitations of card slots and electronic paper cards.

[0083] However, although this embodiment lists specific key derivation functions and AES-CTR modes, for the same purpose of generating secure session keys and encrypting the data to be updated, if there are other key derivation functions or symmetric encryption modes with equivalent cryptographic security strength, such as the SM3 key derivation function based on the national cryptographic algorithm or the SM4 block cipher working mode, they can also be considered to replace the above specific functions and modes to achieve similar effects, which will not be elaborated further.

[0084] In this embodiment, the card slot uses a key derivation function to perform derivation operations on the UID, random challenge number, and first preset key, so that the generated first session key changes with the UID and random challenge number, reducing the risk of key replay. Then, the first session key is used to encrypt the content data to be updated in AES-CTR mode to obtain encrypted content data. This ensures that the content data to be updated exists in ciphertext form during the transmission of the card slot to the electronic paper card, reducing the possibility of data being illegally eavesdropped or tampered with, thereby achieving secure data transmission during the content update process of the electronic paper card.

[0085] In one embodiment, after the above step "sending encrypted content data to the electronic paper card", the following steps may also be included: Receive the first update feedback message sent by the electronic paper card, which is sent by the electronic paper card after performing a content update based on the encrypted content data; Based on the first update feedback message, send the second update feedback message to the server; Both the first update feedback message and the second update feedback message are used to indicate whether the content update of the electronic paper card was successful.

[0086] Specifically, the system first needs to receive a first update feedback message from the electronic paper card. This first update feedback message is sent by the electronic paper card after it has performed a content update based on the encrypted content data. The first update feedback message indicates whether the content update of the electronic paper card was successful.

[0087] Regarding this step, in some possible implementations, after sending encrypted content data to the electronic paper card, the card holder can maintain a contact communication connection with the electronic paper card and listen to the data receiving channel on that contact communication connection. When the electronic paper card completes content updates based on the encrypted content data and sends a first update feedback message through the contact communication connection, the card holder receives the first update feedback message from the data receiving channel.

[0088] Furthermore, based on the first update feedback message, a second update feedback message is sent to the server; wherein, the second update feedback message is used to indicate whether the content update of the electronic paper card was successful.

[0089] Regarding this step, in some possible implementations, after parsing the first update feedback message to obtain the content update status of the electronic paper card, the card holder can encapsulate the content update status into a second update feedback message conforming to the network transmission protocol. Subsequently, the card holder sends the second update feedback message to the server through the established network communication connection.

[0090] In this embodiment, the card holder receives a first update feedback message sent by the electronic paper card after performing a content update based on encrypted content data, and sends a second update feedback message to the server based on the first update feedback message. This enables the server to obtain the result of whether the content update of the electronic paper card was successful, realizing the synchronization of the electronic paper card content update status between the card holder and the server, which facilitates the server to record and manage the content update process of the electronic paper card.

[0091] In one embodiment, after the above step "verifying the response value based on the first preset key, UID, and random challenge number to obtain the verification result", the following steps may also be included: If the verification result indicates that the verification failed, the first number of authentication failures is accumulated, and an authentication failure notification is sent to the electronic paper card. If the number of authentication failures reaches a preset first threshold, a lock notification is sent to the server, and the lock notification carries the UID.

[0092] Specifically, if the verification result indicates that the verification failed, it should first be noted that the electronic paper card has failed the identity verification and poses a security risk of being impersonated or tampered with by unauthorized devices. At this point, the first authentication failure count can be accumulated, and an authentication failure notification can be sent to the electronic paper card. The first authentication failure count refers to the cumulative count of verification failures recorded within the current authentication cycle or in historical authentication processes; the authentication failure notification is a control command used to inform the user of the verification failure status and instruct the triggering of the corresponding defense mechanism.

[0093] Regarding this step, in some possible implementations, after the card slot determines that the verification result indicates that the verification failed, it can call the built-in counter to increment the first authentication failure count, encapsulate the authentication failure notification into an instruction frame that conforms to the protocol format corresponding to the contact communication connection, and send the authentication failure notification to the electronic paper card through the contact communication connection so that the electronic paper card can perform the corresponding defense operation based on the authentication failure notification.

[0094] Furthermore, if the number of authentication failures reaches a preset first threshold, a lock notification is sent to the server, carrying a UID. The preset first threshold refers to a pre-configured maximum failure count threshold used to determine whether to trigger a device lock state; the lock notification is a request message used to request permission restriction operations on the electronic paper card.

[0095] Regarding this step, in some possible implementations, when the number of first authentication failures increases to a preset first threshold, the card holder can encapsulate the UID as an identity identifier in a lock notification and send the lock notification to the server through an established network communication connection, so that the server can mark the electronic paper card corresponding to the UID as locked based on the lock notification.

[0096] In this embodiment, the card holder accumulates the first number of authentication failures when the verification result indicates that the verification has failed and sends an authentication failure notification to the electronic paper card, so that the electronic paper card can be informed of the authentication failure status in a timely manner. At the same time, when the first number of authentication failures reaches a preset first threshold, a lock notification carrying a UID is sent to the server, so that the server can perform remote lock management on the electronic paper card. This effectively blocks attack behavior when encountering repeated illegal authentication attempts and improves the security of the content update authentication process.

[0097] In one embodiment, the content update authentication method of this application may further include the following steps: In response to receiving an unlock trigger operation for a locked e-paper card, an unlock request is sent to the server, carrying the UID in the unlock request; Receive the unlock credential corresponding to the UID sent by the server when the unlock request meets the preset verification conditions; Send an unlock command carrying an unlock credential to the electronic paper card to unlock it.

[0098] Specifically, the system first needs to respond to a received unlock trigger operation for a locked e-paper card by sending an unlock request to the server, which carries a UID. Here, "locked state" refers to a restricted mode where the e-paper card refuses to respond to regular commands due to authentication failure reaching a threshold; "unlock trigger operation" refers to a user command or external input signal used to request the restoration of the e-paper card's normal communication permissions; and "unlock request" refers to a message used to request unlock permissions from the server.

[0099] Regarding this step, in some possible implementations, after receiving an unlock trigger operation for a locked electronic paper card, the card holder can encapsulate the UID corresponding to the locked electronic paper card as an identity identifier in the unlock request, and send the unlock request to the server through the established network communication connection so that the server can verify the unlock request.

[0100] It should be further noted that the unlocking trigger operation for a locked e-paper card may be an unlock confirmation command input by the user through a physical button or touch screen on the card slot after the card slot detects the insertion of a locked e-paper card; it may also be a system trigger command automatically generated by the card slot after detecting the insertion of a locked e-paper card to attempt to restore the e-paper card's usage rights; or it may be a remote control command forwarded to the card slot by a terminal device that is connected to the card slot after receiving the user's unlock instruction; this embodiment does not limit the specific implementation method of the unlocking trigger operation.

[0101] Furthermore, the system receives an unlocking credential corresponding to the UID sent by the server when the unlocking request meets preset verification conditions. The preset verification conditions refer to the standards used by the server to verify the legality and authorization status of the unlocking request; the unlocking credential refers to data used to prove the legality of unlocking permission and its ability to be recognized by the electronic paper card to remove restrictions.

[0102] Regarding this step, in some possible implementations, the card slot can receive the unlocking credential sent by the server through an established network communication connection. The unlocking credential is generated by the server when it determines that the unlocking request meets the preset verification conditions, and the unlocking credential corresponds to the UID.

[0103] Furthermore, an unlocking command carrying an unlocking credential is sent to the electronic paper card to release it from its locked state. The unlocking command refers to a control message used to instruct the electronic paper card to unlock.

[0104] Regarding this step, in some possible implementations, the card slot can encapsulate the unlocking credential as an instruction payload in the unlocking instruction, and send the unlocking instruction carrying the unlocking credential to the electronic paper card through a contact communication connection, so that the electronic paper card can verify the unlocking credential and unlock the electronic paper card after the verification is successful.

[0105] In this embodiment, the card holder sends an unlock request carrying a UID to the server in response to the unlock trigger operation. This enables the server to issue an unlock credential corresponding to the UID when the unlock request meets the preset verification conditions. The card holder then sends an unlock instruction carrying the unlock credential to the electronic paper card to unlock the electronic paper card. Thus, after the lock state is triggered, the unlock credential is obtained and the electronic paper card is unlocked through the interaction between the server and the card holder.

[0106] In one embodiment, the content update authentication method of this application may further include the following steps: Send a certificate reading command to the electronic paper card; Receive the content digital certificate sent by the electronic paper card; the content digital certificate is a digital certificate stored in the electronic paper card. Send a verification request to the server, which includes the UID and the content digital certificate. The server receives the copyright verification result in response to the verification request. The copyright verification result is used to indicate the authenticity of the copyright and / or ownership of the electronic paper card.

[0107] Specifically, the first step is to send a certificate reading command to the electronic paper card. This certificate reading command refers to the control command used to request the reading of the digital certificate stored in the electronic paper card.

[0108] Regarding this step, in some possible implementations, when copyright verification is required, the card slot can encapsulate the certificate reading instruction into an instruction frame conforming to the protocol format of the contact communication connection, and send the certificate reading instruction to the electronic paper card through the contact communication connection, so that the electronic paper card can read the stored digital certificate according to the certificate reading instruction.

[0109] Furthermore, the system receives a content digital certificate sent by the electronic paper card. This content digital certificate is a digital certificate stored within the electronic paper card. Specifically, the content digital certificate refers to an electronic credential used to represent the identity and copyright information of the content data stored on the electronic paper card.

[0110] Regarding this step, in some possible implementations, the card holder can receive the content digital certificate sent by the electronic paper card via a contact communication connection, and parse and cache the content digital certificate for subsequent transmission to the server.

[0111] Furthermore, a verification request is sent to the server, carrying the UID and content digital certificate. The verification request refers to the message used to request the server to compare and verify the UID and content digital certificate.

[0112] Regarding this step, in some possible implementations, the card slot can encapsulate the UID and content digital certificate as payload fields in the verification request, and send the verification request to the server through the established network communication connection, so that the server can compare and verify the UID and content digital certificate in the verification request.

[0113] Furthermore, the receiving server sends a copyright verification result in response to the verification request. This result is used to indicate the authenticity and / or ownership of the copyright of the electronic paper card. Authenticity refers to the determination of whether the content data stored on the electronic paper card is authorized original data; ownership refers to the information of the rights holder corresponding to the content data stored on the electronic paper card.

[0114] Regarding this step, in some possible implementations: On one hand, the card slot can receive the copyright verification result sent by the server in response to the verification request via an established network communication connection. This copyright verification result is generated by the server by comparing the content digital certificate with a pre-stored benchmark certificate, thus indicating the authenticity of the electronic paper card's copyright. On the other hand, the card slot can receive the copyright verification result sent by the server in response to the verification request via an established network communication connection. This copyright verification result is generated by the server by querying the registered user information corresponding to the UID, thus indicating the copyright ownership of the electronic paper card. It should be noted that when the server simultaneously performs certificate comparison and registered user information query, the copyright verification result can simultaneously indicate both the authenticity and ownership of the electronic paper card's copyright.

[0115] In this embodiment, the card holder sends a certificate reading instruction to the electronic paper card and receives the content digital certificate. Then, it sends a verification request carrying the UID and the content digital certificate to the server, enabling the server to verify the UID and the content digital certificate and return the copyright verification result. Thus, the interaction between the card holder and the server enables remote verification of the copyright status of the content data stored on the electronic paper card.

[0116] Please see Figure 2 , Figure 2 This is a flowchart illustrating another content update authentication method provided in an embodiment of this application. Figure 2 As shown, the method of this application embodiment is applied to electronic paper cards and may include the following steps S201~S208: S201, when the card slot and the electronic paper card are in contact communication connection, receives the UID reading command sent by the card slot; S202: Read the UID of the electronic paper card according to the UID reading instruction, and send the UID to the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. S203, Receive the random challenge number sent by the card slot; S204, calculate the response value based on the second preset key, UID and random challenge number, and send the response value to the card slot; S205, Receive encrypted content data sent by the card slot after the verification response value is passed; S206, derive the second session key based on the UID, the random challenge number, and the second preset key; S207, Decrypt the encrypted content data according to the second session key to obtain the content data to be updated; S208 refreshes the display content of the e-paper card based on the data to be updated.

[0117] Specifically, the first step is to receive the UID reading command sent by the card slot when the card slot and the electronic paper card are in a contact communication connection.

[0118] Regarding this step, in some possible implementations, after the electronic paper card detects that a contact communication connection has been established with the card holder, it can listen for and receive the UID reading instruction sent by the card holder in a preset communication frame format through the data receiving channel corresponding to the contact communication connection.

[0119] Furthermore, the UID of the electronic paper card is read according to the UID reading instruction, and the UID is sent to the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten.

[0120] Regarding this step, in some possible implementations, the electronic paper card can parse the received UID reading instruction. After successful parsing, it accesses the dedicated register area corresponding to its built-in MCU, reads the factory-fixed and unrewritable identifier, i.e., the UID, from the dedicated register area, and then encapsulates the UID as response data into a data frame conforming to the communication frame format, and sends it to the card slot through a contact communication connection.

[0121] Furthermore, receive random challenge numbers sent by the card slot.

[0122] Regarding this step, in some possible implementations, an electronic paper card can be connected via contact communication to receive a random challenge number generated by a random number generator and encapsulated as an instruction frame payload by the card slot.

[0123] Further, a response value is calculated based on the second preset key, UID, and random challenge number, and then the response value is sent to the card slot.

[0124] Regarding this step, in some possible implementations, the electronic paper card can read a pre-stored second preset key from its internal non-volatile memory, use the second preset key as a key parameter, concatenate the UID and random challenge number into input data, call the message authentication code operation logic to process the input data, and use the output digest data or authentication tag data as the response value. Then, the response value is encapsulated into a data frame and sent to the card slot through a contact communication connection.

[0125] Furthermore, the receiving card slot sends encrypted content data after the verification response value is passed.

[0126] Regarding this step, in some possible implementations, the electronic paper card can maintain a contact communication connection with the card slot and listen to the data receiving channel after sending a response value to the card slot. When the card slot verifies the response value, it can receive the encrypted content data sent by the card slot through the contact communication connection.

[0127] Furthermore, a second session key is derived based on the UID, the random challenge number, and the second preset key. The second session key refers to the temporary key used for decrypting data in this communication session.

[0128] Regarding this step, in some possible implementations, the UID and random challenge number can be concatenated as input material using an electronic paper card. The same key derivation function as the card holder is used in combination with a second preset key to perform derivation operations, generating a second session key that matches the first session key of the card holder.

[0129] Furthermore, the encrypted content data is decrypted using the second session key to obtain the content data to be updated.

[0130] Regarding this step, in some possible implementations, the electronic paper card can use the second session key as a symmetric decryption key, and use the decryption mode corresponding to the encryption process to decrypt the encrypted content data, converting the encrypted content data into plaintext form, thereby obtaining the content data to be updated.

[0131] Furthermore, the display content of the electronic paper card is refreshed based on the data to be updated.

[0132] Regarding this step, in some possible implementations, the electronic paper card can write the decrypted content data to be updated into the display cache corresponding to the electronic paper display screen, and send a refresh command to the electronic paper display screen so that the electronic paper display screen can execute a refresh sequence according to the refresh command, thereby refreshing the display content of the electronic paper card.

[0133] In this embodiment, the electronic paper card receives a UID read command from the card slot and returns its built-in MCU's factory-fixed and unrewriteable identifier, the UID. It then receives a random challenge number from the card slot and calculates a response value using its stored second preset key, UID, and random challenge number, returning it to the card slot for verification. After successful verification, the electronic paper card receives encrypted content data from the card slot and derives a second session key based on the UID, random challenge number, and second preset key. This second session key is used to decrypt the encrypted content data to obtain the content data to be updated, and the displayed content is then refreshed based on this updated content data. This process allows the electronic paper card to complete the authentication interaction with the card slot without exposing the second preset key, and securely decrypts the encrypted content data using its derived second session key, ensuring data confidentiality and integrity during the content update process.

[0134] In one embodiment, after the above step of "refreshing the display content of the electronic paper card according to the content data to be updated", the following steps may also be included: Send a first update feedback message to the card slot. The first update feedback message is used to indicate whether the content update of the electronic paper card was successful. Enter static hold mode. Static hold mode is used to keep the refreshed display content displayed after the electronic paper card is powered off.

[0135] Specifically, the first step is to send a first update feedback message to the card slot, which indicates whether the content update of the electronic paper card was successful.

[0136] Regarding this step, in some possible implementations, after the electronic paper card refreshes the displayed content based on the content data to be updated, it can evaluate the status of the content update execution result, generate a first update feedback message to indicate whether the content update was successful, and then encapsulate the first update feedback message into a data frame that conforms to the protocol format of the contact communication connection, and send it to the card slot through the contact communication connection.

[0137] Furthermore, it enters static hold mode, which ensures that the refreshed display content remains visible even after the e-paper card is powered off. Static hold mode refers to the e-paper display maintaining the current image after it stops receiving refresh drive signals; power off refers to the e-paper card being disconnected from the external power source or ceasing to receive power supply voltage.

[0138] Regarding this step, in some possible implementations, after the electronic paper card completes the refresh of the displayed content, it can send a state switching command to its internal electronic paper display screen, controlling the electronic paper display screen to stop receiving refresh drive signals and enter a static hold mode, so that the refreshed display content can still be displayed after the electronic paper card is powered off.

[0139] It should be noted that e-paper cards typically rely on a card holder for power. After the content update is complete, the card holder may disconnect the contact communication connection and stop supplying power. By entering a static hold mode, e-paper cards utilize the bistable characteristics of e-ink display technology to maintain the display content even after power is cut off, thus ensuring that e-paper cards still have offline display capabilities after being removed from the card holder.

[0140] In this embodiment, after the electronic paper card refreshes the displayed content according to the content data to be updated, it sends a first update feedback message to the card slot, so that the card slot can know the execution status of the content update. At the same time, the electronic paper card enters a static retention mode, and uses the bistable characteristic to keep the refreshed display content displayed after power failure, thereby achieving persistent presentation of the content without relying on external continuous power supply.

[0141] In one embodiment, the content update authentication method of this application may further include the following steps: The receiver card slot sends an authentication failure notification after the verification response value fails. Based on the authentication failure notification, accumulate the number of second authentication failures; If the number of second authentication failures reaches a preset second threshold, the electronic paper card is locked. The locked state is used to prevent the electronic paper card from responding to any commands other than the unlock command.

[0142] Specifically, the first step is to receive an authentication failure notification sent by the card slot after the verification response value fails.

[0143] Regarding this step, in some possible implementations, the electronic paper card can maintain a contact communication connection with the card slot and listen to the data receiving channel after sending a response value to the card slot. When the card slot fails to verify the response value, it can receive an authentication failure notification sent by the card slot through the contact communication connection.

[0144] Furthermore, based on the authentication failure notification, the number of second authentication failures is accumulated. The number of second authentication failures refers to the cumulative count of card slot response value verification failures recorded within the current authentication cycle or in historical authentication processes.

[0145] Regarding this step, in some possible implementations, the electronic paper card can parse the received authentication failure notification. After successful parsing, it can call the built-in counter to increment the number of second authentication failures, thereby accumulating the number of second authentication failures.

[0146] Furthermore, if the number of second authentication failures reaches a preset second threshold, the electronic paper card is locked. The locked state prevents the electronic paper card from responding to commands other than unlocking commands. The preset second threshold refers to a pre-configured maximum number of failures required to determine whether the electronic paper card triggers the device lock state.

[0147] Regarding this step, in some possible implementations, the electronic paper card can compare the number of second authentication failures with a preset second threshold after each accumulated second authentication failure. When the number of second authentication failures reaches the preset second threshold, the electronic paper card sets a lock flag in its internal non-volatile memory, putting the electronic paper card into a locked state, so that the electronic paper card refuses to respond to any commands other than the unlock command when it is in the locked state.

[0148] In this embodiment, the electronic paper card receives an authentication failure notification sent by the card holder after the verification response value fails, accumulates a second authentication failure count, and locks the electronic paper card when the second authentication failure count reaches a preset second threshold. This causes the electronic paper card to refuse to respond to any commands other than the unlock command, thereby blocking subsequent data interaction when encountering repeated illegal authentication attempts and improving the security of the content update authentication process.

[0149] In one embodiment, the content update authentication method of this application may further include the following steps: Receive the unlock command sent by the card slot, which carries the unlock credentials; Verify the unlocking credentials carried in the unlocking command; Once the unlocking credential verification is successful, the electronic paper card will be unlocked.

[0150] Specifically, you first need to receive an unlocking command sent by the card slot, which carries the unlocking credentials.

[0151] Regarding this step, in some possible implementations, the electronic paper card can maintain a contact communication connection with the card holder and listen to the data receiving channel when it is in a locked state, and receive the unlocking command carrying the unlocking credential sent by the card holder through the contact communication connection.

[0152] Furthermore, the unlocking credentials carried in the unlocking command are verified.

[0153] Regarding this step, in some possible implementations, the electronic paper card can parse the received unlocking command, extract the unlocking credential carried by the unlocking command, and compare the extracted unlocking credential with the baseline unlocking credential pre-stored in the non-volatile memory inside the electronic paper card; if the extracted unlocking credential matches the baseline unlocking credential, the unlocking credential verification is deemed successful; if the extracted unlocking credential does not match the baseline unlocking credential, the unlocking credential verification is deemed unsuccessful.

[0154] Furthermore, once the unlocking credential verification is successful, the electronic paper card is unlocked.

[0155] Regarding this step, in some possible implementations, the electronic paper card can clear the lock flag set in its internal non-volatile memory when it determines that the unlocking credential verification has passed, thus exiting the restricted mode that refuses to respond to commands other than the unlocking command, thereby unlocking the electronic paper card.

[0156] In this embodiment, the electronic paper card receives an unlock command carrying an unlock credential from the card slot, verifies the unlock credential, and unlocks the electronic paper card if the unlock credential verification is successful. Thus, after repeated unauthorized authentication triggers locking, the lock can be released through interaction between the card slot and the electronic paper card, ensuring that the legitimate card slot regains normal access to the electronic paper card.

[0157] In one embodiment, the content update authentication method of this application may further include the following steps: Receive certificate read command sent by the card slot; According to the certificate reading instruction, the stored content digital certificate is read and sent to the card slot.

[0158] Specifically, the first step is to receive the certificate reading command sent by the card slot.

[0159] Regarding this step, in some possible implementations, the electronic paper card can maintain a contact communication connection with the card slot and listen to the data receiving channel, receiving certificate reading instructions sent by the card slot through this contact communication connection.

[0160] Furthermore, based on the certificate reading instruction, the stored content digital certificate is read and sent to the card slot.

[0161] Regarding this step, in some possible implementations, the electronic paper card can parse the received certificate reading instruction. After successful parsing, it can access the designated area in its internal non-volatile memory used to store the digital certificate, read the stored content digital certificate, and then encapsulate the content digital certificate as response data into a data frame conforming to the protocol format of the contact communication connection, and send the content digital certificate to the card slot through the contact communication connection.

[0162] In this embodiment, the electronic paper card receives a certificate reading instruction sent by the card slot, reads the content digital certificate stored inside it, and sends it to the card slot. This enables the card slot to obtain the content digital certificate for the server to perform copyright verification. Thus, without exposing the pre-set key inside the electronic paper card, remote verification of the copyright status of the content data stored on the electronic paper card is achieved.

[0163] Please see Figure 3 , Figure 3 This is a flowchart illustrating another content update authentication method provided in an embodiment of this application. Figure 3 As shown, the method of this application embodiment is applied to the server and may include the following steps S301~S303: S301 receives the UID of the electronic paper card sent by the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. S302, Based on the UID, determine the first preset key and the content data to be updated corresponding to the UID; S303, send the first preset key and the content data to be updated to the card slot.

[0164] Specifically, the first step is to receive the UID of the electronic paper card sent by the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten.

[0165] Regarding this step, in some possible implementations, the server can listen to the data receiving channel through the established network communication connection, receive the acquisition request message carrying the UID after the card slot parses the UID of the electronic paper card, and then parse the UID of the electronic paper card from the acquisition request message. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten.

[0166] Furthermore, based on the UID, the first preset key corresponding to the UID and the content data to be updated are determined.

[0167] Regarding this step, in some possible implementations, the server can use the parsed UID of the electronic paper card as a search index to query the card identity database maintained internally by the server. This card identity database pre-stores the mapping relationship between the UID of the electronic paper card and the first preset key and the content data to be updated. By querying this mapping relationship, the database table entry that matches the UID is located, and then the corresponding first preset key and content data to be updated are extracted from the matching database table entry.

[0168] Furthermore, the first preset key and the content data to be updated are sent to the card slot.

[0169] Regarding this step, in some possible implementations, the server can encapsulate the determined first preset key and the content data to be updated as a response payload into a response message that conforms to the network transmission protocol, and send the response message to the card slot through the established network communication connection, so that the card slot can receive and parse the response message to obtain the first preset key and the content data to be updated.

[0170] In this embodiment, the server receives the UID of the electronic paper card sent by the card slot, determines the corresponding first preset key and the content data to be updated based on the UID, and then sends them to the card slot. This enables the card slot to perform the authentication and content encryption update process of the electronic paper card based on the first preset key and the content data to be updated, thereby realizing the centralized management and distribution of electronic paper card authentication and update data by the server.

[0171] In one embodiment, after the above step "sending the first preset key and the content data to be updated to the card slot", the following steps may also be included: The receiver sends a second update feedback message, which indicates whether the content update of the electronic paper card was successful.

[0172] Specifically, the server can listen to the data receiving channel through the established network communication connection, receive the second update feedback message generated and sent by the card slot according to the content update status of the electronic paper card, and then parse the status identifier used to indicate whether the content update of the electronic paper card was successful from the second update feedback message.

[0173] Furthermore, after receiving the second update feedback message, the server can perform subsequent management operations based on it. On one hand, the server can update the content issuance status record of the electronic paper card maintained internally, based on the success or failure of the content update indicated by the second update feedback message, to keep the server synchronized with the actual content status of the electronic paper card. On the other hand, if the second update feedback message indicates that the content update of the electronic paper card was unsuccessful, the server can trigger a content resend mechanism based on this message, resending the content data to be updated to the card slot to instruct the card slot to execute the content update process again. Additionally, the server can associate the success or failure of the content update of the electronic paper card indicated by the second update feedback message with the corresponding user account or issuance batch for data statistics and auditing.

[0174] It should be noted that after the server sends the first preset key and the content data to be updated to the card slot, the actual content update process performed by the card slot may have different results, such as success or failure, due to factors such as network communication delays, interruptions in contact communication connections, or abnormalities in the internal storage of the electronic paper card. If the server only performs data transmission without obtaining the update result, the content status of the electronic paper card recorded by the server will be inconsistent with the actual displayed content of the electronic paper card, thus affecting subsequent content distribution, copyright verification, and remote management processes. Therefore, by receiving the second update feedback message sent by the card slot, the server can determine whether the content update of the electronic paper card was successful, providing data support for the server's data consistency and closed-loop management.

[0175] In this embodiment, the server receives a second update feedback message from the card slot. Based on the result of whether the content update of the electronic paper card is successful as indicated by the second update feedback message, the server can update the content issuance status record. If the content update is unsuccessful, the server resends the content data to be updated to the card slot. Thus, after the server sends the first preset key and the content data to be updated to the card slot, the server realizes the synchronization and resending control of the content update status of the electronic paper card.

[0176] In one embodiment, the content update authentication method of this application may further include the following steps: Receive a lock notification sent by the card slot. The lock notification is sent by the card slot when the number of first authentication failures reaches a preset first threshold, and the lock notification carries a UID. Based on the lock notification, the e-paper card corresponding to the UID is marked as locked.

[0177] Specifically, it is first necessary to receive a lock notification sent by the card slot. The lock notification is sent by the card slot when the number of first authentication failures reaches a preset first threshold, and the lock notification carries a UID.

[0178] Regarding this step, in some possible implementations, the server can listen to the data receiving channel through the established network communication connection, receive the lock notification generated and sent by the card slot when the number of first authentication failures reaches a preset first threshold, and then parse the UID carried in the lock notification.

[0179] Furthermore, based on the lock notification, the electronic paper card corresponding to the UID is marked as locked.

[0180] Regarding this step, in some possible implementations, the server can use the parsed UID as the retrieval index to query the card registration database maintained internally by the server, locate the status record entry of the electronic paper card corresponding to the UID, and then add or modify the lock flag field in the status record entry to update the status of the electronic paper card corresponding to the UID to the locked state.

[0181] In this embodiment, the server receives a lock notification carrying a UID sent by the card slot when the number of first authentication failures reaches a preset first threshold. Based on the lock notification, the server marks the electronic paper card corresponding to the UID as locked, so that the server can synchronize the restricted status of the electronic paper card. Thus, when a subsequent authentication or content update request for the UID is received, the server refuses to respond based on the locked status, thereby realizing remote access control of the electronic paper card.

[0182] In one embodiment, the content update authentication method of this application may further include the following steps: Receive the unlock request sent by the card slot, the unlock request carries the UID; If the unlock request meets the preset verification conditions, an unlock credential corresponding to the UID is sent to the card slot, so that the card slot sends an unlock command carrying the unlock credential to the electronic paper card.

[0183] Specifically, the first step is to receive an unlock request sent by the card slot, which carries a UID.

[0184] Regarding this step, in some possible implementations, the server can listen to the data receiving channel through an established network communication connection, receive the unlock request encapsulated and sent by the card holder after detecting an unlock trigger operation for an electronic paper card in a locked state, and then parse the UID carried in the unlock request.

[0185] Furthermore, if the unlock request meets the preset verification conditions, an unlock credential corresponding to the UID is sent to the card slot, so that the card slot sends an unlock command carrying the unlock credential to the electronic paper card.

[0186] Regarding this step, in some possible implementations, the server can compare and verify the UID in the parsed unlock request with preset verification conditions. These verification conditions include the legality of the locked state of the electronic paper card corresponding to the UID and the operation permission verification. If the unlock request meets the preset verification conditions, the server queries the corresponding unlock credential generation record based on the UID, generates or extracts the unlock credential corresponding to the UID, encapsulates the unlock credential into a response message, and sends the unlock credential corresponding to the UID to the card slot through the established network communication connection, so that the card slot sends an unlock command carrying the unlock credential to the electronic paper card.

[0187] In this embodiment, the server receives the unlock request sent by the card slot and sends an unlock credential corresponding to the UID to the card slot if the unlock request meets the preset verification conditions. This enables the card slot to send an unlock command carrying the unlock credential to the electronic paper card. Thus, after the electronic paper card enters a locked state due to the first authentication failure count reaching a preset first threshold, the server realizes the remote authorization release of the locked state of the electronic paper card.

[0188] In one embodiment, the content update authentication method of this application may further include the following steps: The card slot receives a verification request, which carries a UID and a content digital certificate. The content digital certificate is a digital certificate that the card slot reads from the electronic paper card. Based on the UID, query the registered digital certificate corresponding to the UID. The registered digital certificate is a pre-registered and stored digital certificate. The content digital certificate is compared with the registered digital certificate to obtain the copyright verification result; Send the copyright verification result to the card slot. The copyright verification result is used to indicate the authenticity of the copyright and / or ownership of the electronic paper card.

[0189] Specifically, it first needs to receive a verification request sent by the card slot. The verification request carries a UID and a content digital certificate. The content digital certificate is a digital certificate that the card slot reads from the electronic paper card.

[0190] Regarding this step, in some possible implementations, the server can listen to the data receiving channel through an established network communication connection, receive the verification request that the card holder encapsulates and sends after reading the content digital certificate from the electronic paper card, and then parse the UID and content digital certificate carried in the verification request.

[0191] Furthermore, based on the UID, the system queries the registered digital certificate corresponding to the UID. The registered digital certificate is a pre-registered and stored digital certificate. Specifically, the registered digital certificate refers to a digital credential pre-stored on the server and used as a basis for copyright verification.

[0192] Regarding this step, in some possible implementations, the server can use the parsed UID as a search index to query the copyright database maintained internally by the server. This copyright database pre-registers and stores the mapping relationship between the UIDs of electronic paper cards and the registered digital certificates. By querying this mapping relationship, the database table entry that matches the UID is located, and then the corresponding registered digital certificate is extracted from the matching database table entry.

[0193] Furthermore, the content digital certificate is compared with the registered digital certificate to obtain the copyright verification result.

[0194] Regarding this step, in some possible implementations, the server can perform a byte-by-byte or feature-value comparison between the extracted registration digital certificate and the parsed content digital certificate; if the content digital certificate matches the registration digital certificate, a copyright verification result indicating that the copyright of the electronic paper card is genuine is obtained; if the content digital certificate does not match the registration digital certificate, a copyright verification result indicating that the copyright of the electronic paper card is fake is obtained.

[0195] Furthermore, the copyright verification result is sent to the card slot, which is used to indicate the authenticity of the copyright and / or ownership of the electronic paper card.

[0196] Regarding this step, in some possible implementations, the server can encapsulate the obtained copyright verification result as a response payload into a response message conforming to the network transmission protocol, and send the response message to the card slot through the established network communication connection, so that the card slot can receive and parse the response message to obtain the copyright verification result used to indicate the authenticity and / or ownership of the copyright of the electronic paper card.

[0197] In this embodiment, the server receives a verification request from the card slot carrying a UID and a content digital certificate. Based on the UID, the server queries the corresponding registered digital certificate, compares the content digital certificate with the registered digital certificate to obtain the copyright verification result, and then sends it to the card slot. This enables the server to remotely compare and verify the content digital certificate of the electronic paper card based on the pre-registered and stored registered digital certificate, thereby achieving accurate verification of the authenticity and / or ownership of the copyright of the electronic paper card.

[0198] In one embodiment, please refer to Figure 4 , Figure 4 This is a schematic diagram of the interactive process of a content update authentication method provided in an embodiment of this application.

[0199] Specifically, when the card slot and the electronic paper card are in a contact communication connection, the card slot sends a UID read command to the electronic paper card; correspondingly, the card slot receives the UID sent by the electronic paper card according to the UID read command. The UID is an identifier that is factory-fixed by the MCU built into the electronic paper card and cannot be rewritten.

[0200] Furthermore, the card slot obtains the first preset key corresponding to the UID and the content data to be updated. Specifically, on the one hand, the card slot sends the UID to the server and receives the first preset key corresponding to the UID and the content data to be updated sent by the server; on the other hand, the card slot reads the first preset key corresponding to the UID and the content data to be updated stored locally on the card slot.

[0201] Furthermore, the card holder generates and sends a random challenge number to the electronic paper card; the card holder receives the response value sent by the electronic paper card, which is calculated by the electronic paper card based on the second preset key, UID, and random challenge number.

[0202] Furthermore, the card slot calculates the expected response value using a message authentication code algorithm based on the first preset key, UID, and random challenge number. The message authentication code algorithm is either HMAC-SHA256 or AES-CMAC. The card slot then compares the expected response value with the response value to obtain the verification result.

[0203] Furthermore, if the verification result indicates that the verification is successful, the card holder uses a key derivation function to perform derivation operations on the UID, random challenge number, and first preset key to obtain the first session key. The key derivation function includes HKDF-SHA256. The card holder uses the first session key to encrypt the content data to be updated in AES-CTR mode to obtain encrypted content data, and sends the encrypted content data to the electronic paper card.

[0204] Furthermore, after receiving the encrypted content data, the electronic paper card derives a second session key based on the UID, the random challenge number, and the second preset key; the electronic paper card decrypts the encrypted content data based on the second session key to obtain the content data to be updated, and refreshes the display content of the electronic paper card based on the content data to be updated.

[0205] Furthermore, the electronic paper card sends a first update feedback message to the card slot and enters static retention mode, which is used to keep the refreshed display content displayed after the electronic paper card is powered off.

[0206] Furthermore, based on the first update feedback message, the card holder sends a second update feedback message to the server. Both the first and second update feedback messages are used to indicate whether the content update of the electronic paper card was successful.

[0207] In this embodiment, the card holder, electronic paper card, and server complete a full content update authentication process through the aforementioned interactions, from UID reading, key acquisition, challenge response verification to encrypted content data transmission, decryption, and display content refresh. If the verification result indicates successful verification, the content data to be updated is transmitted between the card holder and the electronic paper card in encrypted form, ensuring data confidentiality during the content update process. After completing the content update, the electronic paper card sends a first update feedback message, which the card holder then sends a second update feedback message to the server, enabling the server to determine whether the electronic paper card's content update was successful. The electronic paper card enters a static retention mode, ensuring that the refreshed display content remains visible even after the electronic paper card is powered off.

[0208] In one embodiment, please refer to Figure 5 , Figure 5 This is a schematic diagram of the interaction flow of another content update authentication method provided in the embodiments of this application.

[0209] Specifically, if the verification result indicates that the verification failed, the card slot accumulates the first number of authentication failures and sends an authentication failure notification to the electronic paper card; the electronic paper card accumulates the second number of authentication failures based on the authentication failure notification.

[0210] Furthermore, if the number of second authentication failures reaches a preset second threshold, the electronic paper card will be locked. The locked state is used to prevent the electronic paper card from responding to any commands other than the unlock command.

[0211] Furthermore, if the number of authentication failures reaches a preset first threshold, the card holder sends a lock notification to the server, which carries a UID; the server marks the electronic paper card corresponding to the UID as locked based on the lock notification.

[0212] Furthermore, in response to receiving an unlock trigger operation for a locked electronic paper card, the card holder sends an unlock request to the server, the unlock request carrying a UID; if the unlock request meets preset verification conditions, the server sends an unlock credential corresponding to the UID to the card holder; the card holder sends an unlock command carrying the unlock credential to the electronic paper card; the electronic paper card verifies the unlock credential carried in the unlock command; if the unlock credential verification passes, the electronic paper card is unlocked.

[0213] Furthermore, in the copyright verification process, the card slot sends a certificate reading instruction to the electronic paper card; the electronic paper card reads the stored content digital certificate according to the certificate reading instruction and sends the content digital certificate back to the card slot; the card slot sends a verification request to the server, the verification request carrying the UID and the content digital certificate; the server queries the registered digital certificate corresponding to the UID based on the UID; the server compares the content digital certificate with the registered digital certificate to obtain the copyright verification result; the server sends the copyright verification result to the card slot, and the copyright verification result is used to indicate the authenticity of the copyright and / or the ownership of the copyright of the electronic paper card.

[0214] In this embodiment, when the verification result indicates that the verification failed, the card holder and the electronic paper card accumulate the first authentication failure count and the second authentication failure count, respectively. When the accumulated counts reach the corresponding thresholds, the server is triggered to mark the electronic paper card corresponding to the UID as locked and the electronic paper card itself as locked, thereby blocking subsequent data interaction when encountering repeated illegal authentication attempts. During the unlocking process, the server verifies the unlocking request, issues the unlocking certificate, and the electronic paper card verifies the unlocking certificate to unlock the electronic paper card. In the copyright verification process, the server compares the content digital certificate with the registration digital certificate to obtain the copyright verification result and sends it to the card holder, thereby verifying the authenticity and / or ownership of the copyright of the electronic paper card.

[0215] In one embodiment, taking a scenario of merchants issuing cards in bulk as an example, the content update authentication methods of the above embodiments are comprehensively described. The system involved in this embodiment includes a server, a hub control device, multiple card slots, and an electronic paper card that is communicatively connected to each card slot.

[0216] Specifically, the e-paper card includes an MCU with a built-in UID, an e-paper display, and non-volatile memory. The UID is a factory-fixed identifier for the MCU built into the e-paper card and cannot be rewritten. It is a 96-bit or 128-bit hardware serial number, fixed by the chip manufacturer during wafer testing using a fuse or laser, and cannot be erased or rewritten by any software commands. The e-paper display is a 3.68-inch, 480×480 resolution monochrome e-paper display. The non-volatile memory has a capacity of 128KB to 256KB and is used to store encrypted content data, content digital certificates, and a second pre-set key. The e-paper card establishes physical contact with the card holder through gold finger contacts located on its edge. These gold finger contacts are recessed 0.3mm from the edge of the e-paper card to increase the difficulty of contact by unauthorized reading and writing devices.

[0217] Specifically, the card slot includes a microcontroller and physical contacts. The physical contacts adopt a spring-loaded pin structure with a contact life of no less than 100,000 cycles. The contact definitions include power supply pins, ground pins, and signal pins corresponding to the serial peripheral interface, supporting full-duplex serial peripheral interface communication at a communication rate of 10MHz to 40MHz. The hub control device is implemented as a computer device running management software. It establishes a network communication connection with the server via a wired Ethernet network and addresses and controls up to 16 card slots through a bus mechanism and independent chip select signals corresponding to each card slot. Each card slot is communicatively connected to one electronic paper card. The card slot and the electronic paper card establish a serial peripheral interface connection as a contact-type communication connection through gold finger contacts or spring-loaded pin contacts.

[0218] Furthermore, the instructions and data transmitted between the card holder and the electronic paper card via contact communication are encapsulated according to a preset communication frame format. This communication frame format includes five fields in sequence: frame header, instruction code, data length, payload, and checksum. The frame header is 1 byte, with a fixed value of 0x7E, used to identify the start of the frame; the receiver uses this byte to achieve frame synchronization. The instruction code is 1 byte, used to distinguish different control instructions, where 0x01 corresponds to the UID read instruction, 0x02 carries the random challenge number, 0x03 carries the data, 0x81 carries the first update feedback message, and 0xF0 corresponds to the unlock instruction. The data length is 1 byte, used to indicate the actual number of bytes in the payload field, with a value range of 0 to 255. The payload is 0 to 255 bytes, used to carry the actual data corresponding to the instruction code, such as the UID, random challenge number, encrypted content data, or the first update feedback message. The checksum is 1 byte, taken as the XOR value of all bytes from the frame header to the payload; the receiver uses this to verify the integrity of the communication frame.

[0219] Furthermore, a pre-issuance process is executed before bulk card issuance. The copyright holder uploads the original image files to the copyright registration platform. The copyright registration platform calculates a digital certificate for the original image files and stores it, generating a certificate number to establish the copyright ownership of the original images. The issuer generates a content copy corresponding to each electronic paper card based on the issuance volume. Each content copy can embed an identifier representing the issuance serial number and converts the color image into a 1-bit black and white bitmap adapted to the electronic paper display. The conversion process uses the Floyd-Steinberg dithering algorithm to optimize the display effect. Then, a digital certificate is calculated independently for each content copy. Subsequently, a one-to-one mapping relationship is established between the UID of each electronic paper card and the corresponding digital certificate and registered and stored on the server as the registration digital certificate corresponding to the UID. At the same time, a corresponding preset key is assigned to each electronic paper card. The one used on the card holder side is called the first preset key, and the one preset on the electronic paper card side is called the second preset key. Under the symmetric key system, the two are the same. The second preset key is written into the non-volatile memory of the electronic paper card through a secure channel during the electronic paper card registration stage. The hub control device reads the UID of each newly manufactured electronic paper card and registers it to the server, supporting batch import of registration records. The hub control device also synchronizes the first preset key and the content data to be updated corresponding to each UID from the server in advance via a wired Ethernet network, and sends them to the local storage of each card slot for each card slot to execute subsequent processes offline.

[0220] Furthermore, taking one of the card slots and its connected electronic paper card as an example, the complete content update authentication process is illustrated.

[0221] During the triggering phase, the operator inserts the electronic paper card into the card slot. The card slot provides 3.3V operating power to the electronic paper card through its power supply pin. After the MCU of the electronic paper card powers on, it completes initialization operations such as clock configuration, serial peripheral interface initialization, and input / output interface configuration. The clock frequency of the serial peripheral interface is initialized to 10MHz. After initialization, the electronic paper card indicates a ready state to the card slot through the level change of its chip select pin, and the card slot confirms that the contact communication connection has been established. During the power-on initialization phase, the electronic paper card also detects the voltage drop characteristics of the power supply pin to determine the reliability of the contact. In the event of abnormal contact, it refuses to proceed to the subsequent authentication process.

[0222] The card slot encapsulates a UID read instruction with code 0x01 according to the aforementioned communication frame format and sends it to the electronic paper card. After parsing the UID read instruction, the electronic paper card accesses the dedicated register area corresponding to its built-in MCU, reads the factory-fixed and unrewriteable identifier (UID), and encapsulates the UID as the payload into a data frame and returns it. The card slot receives this data frame and parses it to obtain the UID.

[0223] The card slot queries local storage using the UID as an index, retrieving the first preset key and the content data to be updated corresponding to the UID. Subsequently, the card slot calls its built-in random number generator to generate a 32-byte random challenge number, ensuring that two consecutively generated random challenge numbers are not repeated. This random challenge number is then encapsulated as a payload into an instruction frame with instruction code 0x02 and sent to the electronic paper card. At the same time, the UID and the random challenge number are cached locally.

[0224] After receiving a random challenge number, the electronic paper card reads a second preset key from its non-volatile memory. Based on the second preset key, UID, and random challenge number, it calculates a response value using a message authentication code algorithm and encapsulates the response value into a data frame, returning it to the card slot. The message authentication code algorithm is determined based on the MCU's memory resources. When the MCU's memory resources are sufficient, HMAC-SHA256 is used to provide high security strength; when the MCU's memory resources are limited, AES-CMAC is used to reduce computational resource consumption.

[0225] Optionally, the aforementioned message authentication code algorithm can be adapted in a tiered manner based on the memory resource capacity of the MCU built into the electronic paper card. When the MCU's memory resource is greater than or equal to a first preset capacity threshold, the HMAC-SHA256 algorithm is used to provide high-security computation. When the MCU's memory resource is less than the first preset capacity threshold but greater than or equal to a second preset capacity threshold, the AES-CMAC-128 algorithm is used. When the MCU's memory resource is less than the second preset capacity threshold, the AES-CMAC-64 algorithm is used to further reduce computational resource consumption and storage overhead. Through the above tiered adaptation strategy, electronic paper cards with different hardware costs can find matching security algorithms, thereby balancing authentication security and computational efficiency under resource-constrained hardware conditions.

[0226] After receiving the response value, the card slot calculates the expected response value using the same message authentication code algorithm as the electronic paper card, based on the first preset key, UID, and random challenge number. The expected response value is then compared byte by byte with the actual response value to obtain the verification result.

[0227] Optionally, in scenarios with higher security requirements, after the card holder verifies the response value, a reverse verification step for the legitimacy of the card holder's identity can also be executed. The card holder generates a second random challenge number and calculates a reverse response value using its own stored private credentials, and sends the second random challenge number and the reverse response value to the electronic paper card. The electronic paper card calculates the expected reverse response value based on the pre-stored base credentials and the second random challenge number, and compares it with the received reverse response value. If the reverse response values ​​match, the card holder is confirmed to be legitimate and the subsequent process of receiving encrypted content data is executed, thereby realizing two-way device identity authentication between the card holder and the electronic paper card, preventing unauthorized card holders from writing data to legitimate electronic paper cards.

[0228] If the verification result indicates successful verification, the card slot uses a key derivation function to perform derivation operations on the UID, random challenge number, and first preset key to obtain a 128-bit first session key. The key derivation function uses HKDF-SHA256. Correspondingly, the electronic paper card uses the same key derivation function to perform derivation operations on the UID, random challenge number, and second preset key to obtain a second session key that matches the first session key. This first and second session key are only valid during the current communication session and become invalid after the electronic paper card is removed. Upon the next insertion, a new key is derived based on the new random challenge number, thereby reducing the risk of key replay.

[0229] The card slot uses a first session key to encrypt the content data to be updated in AES-CTR mode, resulting in encrypted content data. This encrypted content data is then divided into multiple data blocks, each 256 bytes long. Each block is encapsulated into a data frame with an instruction code of 0x03 and sent to the electronic paper card. After receiving each block, the electronic paper card decrypts the encrypted content data according to the second session key, writes the decrypted content data to be updated into non-volatile memory, and verifies data integrity through cyclic redundancy check.

[0230] Subsequently, the e-paper card writes the decrypted content to be updated into the corresponding display cache of the e-paper display screen and sends a refresh command to the e-paper display screen. The e-paper display screen executes a refresh sequence, including image retention processing, thereby refreshing the display content of the e-paper card. After the update is completed, the e-paper card encapsulates the first update feedback message, which indicates whether the content update was successful, into a data frame with command code 0x81 and sends it to the card slot, and enters a static retention mode, so that the refreshed display content remains displayed after the e-paper card is powered off; the card slot disconnects the power supply after detecting that the refresh is complete.

[0231] Furthermore, each card slot forwards the second update feedback message to the server via the hub control device. The second update feedback message indicates whether the content update of the corresponding e-paper card was successful. The server updates its internally maintained content release status record based on the second update feedback message. The hub control device summarizes the update results of each e-paper card, generates a success and failure list, and the reasons for failure include unregistered UID, mismatched key, and the e-paper card being in a locked state. The log file is then exported and archived.

[0232] Furthermore, during the batch update process, the hub control device addresses and controls the 16 card slots through a bus mechanism and independent chip select signals corresponding to each slot. This allows each card slot and its connected electronic paper card to independently execute the aforementioned authentication and data interaction process. Each electronic paper card independently completes authentication and independently derives its own first session key and second session key, achieving secure isolation between multiple electronic paper cards. Because multiple slots execute in parallel, the content updates of multiple electronic paper cards can be performed simultaneously, improving the efficiency of batch updates.

[0233] Furthermore, the data to be updated may also include firmware upgrade data for updating the MCU program within the e-paper card. The hub control device automatically detects the firmware version of the e-paper card when it is inserted into the card slot. Upon detecting a new firmware version, it obtains the firmware differential upgrade package and performs batch upgrades on multiple e-paper cards using block transmission, cyclic redundancy check, and breakpoint resume. If the upgrade fails, it can roll back to the original version.

[0234] In this embodiment, the merchant side, through the coordination of a hub control device, multiple card slots, and the server, independently completes the entire content update authentication process for each electronic paper card in a batch card issuance scenario. This process includes UID reading, key acquisition, response value verification, first session key derivation, AES-CTR mode encrypted transmission, decryption and writing, and display content refresh. Each electronic paper card uses an independent session key, ensuring the confidentiality and integrity of the content update process for each electronic paper card while maintaining the efficiency of batch updates.

[0235] In one embodiment, based on the system architecture of the above embodiments, a comprehensive explanation is given of the locking after authentication failure, the unlocking of the locking status, and the copyright verification process.

[0236] Specifically, if the card reader verifies the response value based on the first preset key, UID, and random challenge number, and receives a verification result indicating that the verification failed, it means that the electronic paper card has failed the identity verification. Taking a counterfeit electronic paper card as an example, its stored second preset key does not match the first preset key obtained by the card reader, causing its calculated response value to be inconsistent with the expected response value calculated by the card reader. At this time, the card reader accumulates the first authentication failure count and encapsulates the authentication failure notification into an instruction frame, sending it to the electronic paper card via a contact communication connection; after receiving the authentication failure notification, the electronic paper card accumulates the second authentication failure count.

[0237] Furthermore, when the number of second authentication failures reaches a preset second threshold, the electronic paper card sets a lock flag in its non-volatile memory, locking the card. A locked electronic paper card refuses to respond to commands other than unlocking commands. In this embodiment, the preset second threshold is set to 5. When the number of first authentication failures reaches a preset first threshold, the card slot encapsulates the UID as an identity identifier in a lock notification and sends it to the server via the hub control device. In this embodiment, the preset first threshold is set to 5. After receiving the lock notification, the server queries its internally maintained card registration database using the UID as the search index, marks the electronic paper card corresponding to the UID as locked, and refuses to respond to subsequent authentication or content update requests for that UID based on the locked state, thereby achieving remote access control of the electronic paper card.

[0238] Furthermore, during the unlocking process, in response to receiving an unlock trigger operation for a locked e-paper card, the card slot sends an unlock request carrying the UID to the server. The unlock trigger operation can be an unlock confirmation command input by the user via a physical button or touchscreen on the card slot after the card slot detects a locked e-paper card inserted, or a remote control command forwarded to the card slot by a terminal device connected to the card slot after receiving an unlock instruction input by the user. If the unlock request meets preset verification conditions, the server sends an unlock credential corresponding to the UID to the card slot. These preset verification conditions include verification of the legality of the locked state of the e-paper card corresponding to the UID and verification of operation permissions. The unlock credential is configured as a one-time use credential, expiring after one use. The card slot encapsulates the unlock credential as an instruction payload in an unlock command with instruction code 0xF0 and sends it to the e-paper card via a contact communication connection. The electronic paper card parses the unlock command, extracts the unlock credential it carries, and compares the unlock credential with the baseline unlock credential pre-stored in its non-volatile memory. If the unlock credential verification passes, the lock flag is cleared, the electronic paper card is unlocked, and the normal content update authentication process is restored.

[0239] Furthermore, during the copyright verification process, the card slot sends a certificate reading instruction to the electronic paper card. The electronic paper card, according to the instruction, accesses a designated area in its non-volatile memory used to store digital certificates, reads the stored content digital certificate, and sends it back to the card slot. The card slot encapsulates the UID and content digital certificate as payload fields in the verification request and sends it to the server via the established network communication connection. The server queries its internally maintained copyright database for pre-registered digital certificates based on the UID, compares the content digital certificate with the registered digital certificate, and obtains a copyright verification result indicating genuine copyright if they match, and a result indicating counterfeit copyright if they do not match. The server can also query the corresponding registered user information based on the UID, further indicating copyright ownership based on the verification result. The server sends the copyright verification result to the card slot, which displays the result on a touchscreen, showing information including copyright authenticity, issuance batch, issuance time, and certificate number.

[0240] It should be further explained that for cloned e-paper cards, since their UID is not registered on the server, the server cannot find the corresponding registered digital certificate, and the copyright verification result indicates that the copyright is fake; for e-paper cards whose content data has been tampered with, the stored content digital certificate is inconsistent with the registered digital certificate, and the copyright verification result also indicates that the copyright is fake, thereby effectively preventing the cloning and tampering of e-paper cards.

[0241] It should be noted that even when the card slot is offline and lacks a network communication connection, it can still read the content digital certificate stored on the electronic paper card via a contact communication connection and display the summary information of the content digital certificate. The summary information is specifically the first 8 hexadecimal characters of the content digital certificate, which users can manually compare with publicly released benchmark information. This method does not rely on the server, but it cannot verify whether the electronic paper card has been marked as locked.

[0242] In this embodiment, when the verification result indicates that the verification failed, the card holder and the electronic paper card accumulate the number of authentication failures respectively, and trigger a lock when the corresponding threshold is reached, effectively blocking repeated illegal authentication attempts; the authorization to release the locked state is realized through the server's verification of the unlock request, the issuance of the unlock certificate, and the electronic paper card's verification of the unlock certificate; by comparing the content digital certificate with the registration digital certificate, remote verification of the authenticity and ownership of the copyright of the electronic paper card is realized.

[0243] In one embodiment, taking a consumer self-service management scenario as an example, the content update authentication methods of the above embodiments are comprehensively described. The system involved in this embodiment includes a card holder used by the consumer, a terminal device, and a server.

[0244] Specifically, the card holder in this embodiment is a home desktop device. In addition to a microcontroller and physical contacts, it also incorporates a built-in wireless communication module. This module supports a 2.4GHz Wi-Fi network, and the card holder establishes a network communication connection with the server via this network. The card holder is equipped with physical buttons and a touchscreen display for human-computer interaction. The physical buttons include four buttons: up, down, confirm, and back. The card holder also has a small display screen for previewing the sequence numbers of stored images. Users can scan a QR code on the card holder using their terminal device to establish a connection between the terminal device, the card holder, and the user's account. The terminal device can then forward remote control commands to the card holder.

[0245] Furthermore, during the initial binding process, the consumer inserts the e-paper card into the card slot. The card slot automatically performs a UID reading process, that is, it sends a UID reading command to the e-paper card via a contact communication connection and receives the UID returned by the e-paper card. The UID is then sent to the server via a Wi-Fi network. The consumer logs into their user account on the server through their terminal device. The server binds the UID to the user account and records the binding relationship. After binding, the e-paper card becomes a card under that user account. Only the consumer can switch the displayed content of the bound e-paper card, and the server records subsequent changes to the content status of the e-paper card.

[0246] Furthermore, during content download and update, consumers select target content from the content data provided by the server via their terminal devices, or through the physical buttons and touchscreen display of the card slot. Upon receiving the selection, the server sends the first preset key corresponding to the UID and the content data to be updated to the card slot. The card slot generates and sends a random challenge number to the e-paper card, receives the response value returned by the e-paper card, and verifies the response value based on the first preset key, UID, and random challenge number. If the verification result indicates successful verification, the card slot derives a first session key based on the UID, random challenge number, and first preset key, encrypts the content data to be updated in AES-CTR mode, and sends it to the e-paper card. The e-paper card derives a second session key based on the UID, random challenge number, and second preset key, decrypts the encrypted content data, refreshes the displayed content, and then sends a first update feedback message to the card slot and enters static retention mode. The card slot sends a second update feedback message to the server based on the first update feedback message, and the server updates the content release status record corresponding to the UID accordingly. The entire process requires no computer equipment; consumers only need to power on the card slot and connect it to the internet to complete the process.

[0247] Furthermore, during image management, the non-volatile memory of the electronic paper card can store multiple image data. Consumers can view the stored image list and select the currently displayed image via the physical buttons on the card holder, the touch screen, or the terminal device. In response to this selection, the card holder performs an authentication process with the electronic paper card, instructs the card to write the data corresponding to the selected image to the display cache, and refreshes the display. Changes to the content displayed on the electronic paper card are reported to the server by the card holder.

[0248] Furthermore, during the firmware upgrade process, the data to be updated is the firmware upgrade data used to update the MCU program within the e-paper card. The terminal device or card slot detects the firmware version of the e-paper card. If a new firmware version exists on the server, the card slot downloads the firmware differential upgrade package from the server and automatically completes the upgrade when the e-paper card is inserted into the card slot, without the consumer noticing.

[0249] Furthermore, during the remote authorization and sharing process, consumers generate a one-time authorization code through their terminal devices. After the recipient enters the authorization code into their terminal devices, the server temporarily authorizes the recipient's card slot to write content to the electronic paper card, thereby achieving controlled sharing of content.

[0250] Furthermore, during the remote locking and secure recovery process, in the event of a lost e-paper card, the consumer requests remote locking from the server via their terminal device. The server marks the e-paper card corresponding to the UID as locked, and subsequent authentication or content update requests for that UID are rejected by the server, preventing other card holders or other terminal devices from operating the e-paper card. If the e-paper card is locked due to authentication failure, the server pushes a notification to the bound terminal device. If recovery is required, the consumer inputs an unlock instruction via their terminal device, which forwards the unlock instruction to the card holder as an unlock trigger. The card holder, server, and e-paper card interact according to the process described in the above embodiment to unlock the e-paper card.

[0251] Furthermore, during the copyright verification process, consumers select the copyright verification function via the physical buttons or touch screen of the card holder. The card holder sends a certificate reading instruction to the electronic paper card and receives the content digital certificate. It then sends a verification request carrying the UID and content digital certificate to the server. After receiving the copyright verification result returned by the server, the information presented includes the authenticity of the copyright, the issuance batch, the issuance time, and the certificate number. This process does not change the displayed content of the electronic paper card.

[0252] Optionally, during the limited-edition card transfer process, the originally bound terminal device can initiate an unbinding request to the server for the electronic paper card that is already bound. In response to this unbinding request, the server removes the binding relationship between the UID and the current user account and generates an immutable unbinding event audit log. After the electronic paper card is inserted into the card slot, the transferee's terminal device obtains the UID and initiates a binding request to the server. If the UID is in an unbound state, the server establishes a new binding relationship between the UID and the transferee's user account and records the transfer event chain. The above transfer process only changes the account binding relationship on the server side and does not change the content data and content digital certificate stored in the non-volatile memory inside the electronic paper card, thereby ensuring the data integrity and copyright traceability of the limited-edition digital assets during the transfer process.

[0253] In this embodiment, consumers can directly connect to the server via a card slot with a built-in wireless communication module. With the help of terminal devices, they can complete self-service management functions such as account binding, content download and update, image switching, remote authorization and sharing, remote locking and unlocking, and copyright verification for electronic paper cards. All of the above content updates undergo a complete authentication process, including UID reading, response value verification, derivation of the first session key and the second session key, and AES-CTR encrypted transmission. This ensures reliable and low-cost security authentication even in the consumer's personal management scenario.

[0254] The following will combine Figure 6 The first content update authentication device 600 provided in this application embodiment will be described in detail. The first content update authentication device 600 can be referred to in correspondence with the content update authentication method applied to the card slot described above. Specifically, the first content update authentication device 600 may include a first sending module 610, a first receiving module 620, an acquisition module 630, a transceiver module 640, a verification module 650, an encryption module 660, and a second sending module 670, as detailed below: The first sending module 610 is used to send a UID reading command to the electronic paper card when the card holder and the electronic paper card are in a contact communication connection. The first receiving module 620 is used to receive the UID sent by the electronic paper card according to the UID reading instruction. The UID is an identifier that is factory-fixed by the MCU built into the electronic paper card and cannot be rewritten. The acquisition module 630 is used to acquire the first preset key corresponding to the UID and the content data to be updated. The transceiver module 640 is used to generate and send a random challenge number to the electronic paper card, and receive a response value sent by the electronic paper card. The response value is calculated by the electronic paper card based on the second preset key, UID and random challenge number. The verification module 650 is used to verify the response value based on the first preset key, UID and random challenge number, and obtain the verification result; The encryption module 660 is used to derive a first session key based on the UID, random challenge number and first preset key when the verification result indicates that the verification is successful, and to encrypt the content data to be updated based on the first session key to obtain encrypted content data. The second sending module 670 is used to send encrypted content data to the electronic paper card so that the electronic paper card can update its content based on the encrypted content data.

[0255] Optionally, in some embodiments, the acquisition module 630 may be used to: Send the UID to the server and receive the first preset key corresponding to the UID and the content data to be updated from the server. Read the first preset key corresponding to the UID and the content data to be updated stored locally in the card slot.

[0256] Optionally, in some embodiments, the verification module 650 may be used to: Based on the first preset key, UID, and random challenge number, the expected response value is calculated using a message authentication code algorithm, wherein the message authentication code algorithm is HMAC-SHA256 or AES-CMAC; The expected response value is compared with the actual response value to obtain the verification result.

[0257] Optionally, in some embodiments, the encryption module 660 can be used for: The first session key is obtained by performing derivation operations on the UID, random challenge number and first preset key using key derivation functions, wherein the key derivation functions include HKDF-SHA256; Using the first session key, the content data to be updated is encrypted in AES-CTR mode to obtain encrypted content data.

[0258] Optionally, in some embodiments, the second transmitting module 670 may be used for: Receive the first update feedback message sent by the electronic paper card, which is sent by the electronic paper card after performing a content update based on the encrypted content data; Based on the first update feedback message, send the second update feedback message to the server; Both the first update feedback message and the second update feedback message are used to indicate whether the content update of the electronic paper card was successful.

[0259] Optionally, in some embodiments, the verification module 650 may be used to: If the verification result indicates that the verification failed, the first number of authentication failures is accumulated, and an authentication failure notification is sent to the electronic paper card. If the number of authentication failures reaches a preset first threshold, a lock notification is sent to the server, and the lock notification carries the UID.

[0260] Optionally, in some embodiments, the first content update authentication device 600 can be used to: In response to receiving an unlock trigger operation for a locked e-paper card, an unlock request is sent to the server, carrying the UID in the unlock request; Receive the unlock credential corresponding to the UID sent by the server when the unlock request meets the preset verification conditions; Send an unlock command carrying an unlock credential to the electronic paper card to unlock it.

[0261] Optionally, in some embodiments, the first content update authentication device 600 can be used to: Send a certificate reading command to the electronic paper card; Receive the content digital certificate sent by the electronic paper card; the content digital certificate is a digital certificate stored in the electronic paper card. Send a verification request to the server, which includes the UID and the content digital certificate. The server receives the copyright verification result in response to the verification request. The copyright verification result is used to indicate the authenticity of the copyright and / or ownership of the electronic paper card.

[0262] For the effects achievable in this embodiment, please refer to the relevant embodiments of the content update authentication method applied to card slots described above, which will not be repeated here.

[0263] The following will combine Figure 7 The second content update authentication device 700 provided in this application embodiment will be described in detail. The second content update authentication device 700 can be referred to in correspondence with the content update authentication method applied to electronic paper cards described above. Specifically, the second content update authentication device 700 may include a second receiving module 710, a reading module 720, a third receiving module 730, a calculation module 740, a fourth receiving module 750, a derived module 760, a decryption module 770, and a refresh module 780, as detailed below: The second receiving module 710 is used to receive the UID reading instruction sent by the card slot when the card slot and the electronic paper card are in contact communication connection. The reading module 720 is used to read the UID of the electronic paper card according to the UID reading instruction and send the UID to the card slot. The UID is an identifier that is factory-fixed by the MCU built into the electronic paper card and cannot be rewritten. The third receiving module 730 is used to receive the random challenge number sent by the card slot; Calculation module 740 is used to calculate the response value based on the second preset key, UID and random challenge number, and send the response value to the card slot; The fourth receiving module 750 is used to receive encrypted content data sent by the card slot after the verification response value is passed; Derivation module 760 is used to derive a second session key based on the UID, the random challenge number, and the second preset key; The decryption module 770 is used to decrypt the encrypted content data according to the second session key to obtain the content data to be updated; The refresh module 780 is used to refresh the display content of the electronic paper card based on the data to be updated.

[0264] Optionally, in some embodiments, the refresh module 780 can be used to: Send a first update feedback message to the card slot. The first update feedback message is used to indicate whether the content update of the electronic paper card was successful. Enter static hold mode. Static hold mode is used to keep the refreshed display content displayed after the electronic paper card is powered off.

[0265] Optionally, in some embodiments, the second content update authentication device 700 can be used to: The receiver card slot sends an authentication failure notification after the verification response value fails. Based on the authentication failure notification, accumulate the number of second authentication failures; If the number of second authentication failures reaches a preset second threshold, the electronic paper card is locked. The locked state is used to prevent the electronic paper card from responding to any commands other than the unlock command.

[0266] Optionally, in some embodiments, when the electronic paper card is locked, the second content update authentication device 700 can be used to: Receive the unlock command sent by the card slot, which carries the unlock credentials; Verify the unlocking credentials carried in the unlocking command; Once the unlocking credential verification is successful, the electronic paper card will be unlocked.

[0267] Optionally, in some embodiments, the electronic paper card also stores a content digital certificate; the reading module 720 can be used to: Receive certificate read command sent by the card slot; According to the certificate reading instruction, the stored content digital certificate is read and sent to the card slot.

[0268] For the effects achievable in this embodiment, please refer to the relevant embodiments of the content update authentication method applied to electronic paper cards described above, which will not be repeated here.

[0269] The following will combine Figure 8 The third content update authentication device 800 provided in this application embodiment will be described in detail. The third content update authentication device 800 can be referred to in correspondence with the content update authentication method applied to the server described above. Specifically, the third content update authentication device 800 may include a receiving module 810, a determining module 820, and a sending module 830, as detailed below: The receiving module 810 is used to receive the UID of the electronic paper card sent by the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. The determination module 820 is used to determine the first preset key and the content data to be updated corresponding to the UID based on the UID; The sending module 830 is used to send the first preset key and the content data to be updated to the card slot.

[0270] Optionally, in some embodiments, the sending module 830 may be used to: The receiver sends a second update feedback message, which indicates whether the content update of the electronic paper card was successful.

[0271] Optionally, in some embodiments, the receiving module 810 may be used to: Receive a lock notification sent by the card slot. The lock notification is sent by the card slot when the number of first authentication failures reaches a preset first threshold, and the lock notification carries a UID. Based on the lock notification, the e-paper card corresponding to the UID is marked as locked.

[0272] Optionally, in some embodiments, the third content update authentication device 800 can be used for: Receive the unlock request sent by the card slot, the unlock request carries the UID; If the unlock request meets the preset verification conditions, an unlock credential corresponding to the UID is sent to the card slot, so that the card slot sends an unlock command carrying the unlock credential to the electronic paper card.

[0273] Optionally, in some embodiments, the third content update authentication device 800 can be used for: The card slot receives a verification request, which carries a UID and a content digital certificate. The content digital certificate is a digital certificate that the card slot reads from the electronic paper card. Based on the UID, query the registered digital certificate corresponding to the UID. The registered digital certificate is a pre-registered and stored digital certificate. The content digital certificate is compared with the registered digital certificate to obtain the copyright verification result; Send the copyright verification result to the card slot. The copyright verification result is used to indicate the authenticity of the copyright and / or ownership of the electronic paper card.

[0274] For the effects achieved in this embodiment, please refer to the relevant embodiments of the content update authentication method applied to the server described above, which will not be repeated here.

[0275] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0276] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of various embodiments or some parts of embodiments.

[0277] All actions involving the acquisition of signal information or data in this application are carried out in accordance with the relevant data protection laws and policies of the country where the application is located, and with the authorization granted by the owner of the relevant device.

[0278] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A content update authentication method, characterized in that, Applied to card slots, the content update authentication method includes: When the card slot and the electronic paper card are in contact communication connection, a UID reading command is sent to the electronic paper card; Receive the UID sent by the electronic paper card according to the UID reading instruction. The UID is an identifier that is factory-fixed by the MCU built into the electronic paper card and cannot be rewritten. Obtain the first preset key and the content data to be updated corresponding to the UID; Generate and send a random challenge number to the electronic paper card, and receive a response value sent by the electronic paper card, wherein the response value is calculated by the electronic paper card based on the second preset key, the UID and the random challenge number; The response value is verified based on the first preset key, the UID, and the random challenge number to obtain the verification result; If the verification result indicates that the verification is successful, a first session key is derived based on the UID, the random challenge number, and the first preset key, and the content data to be updated is encrypted based on the first session key to obtain encrypted content data; The encrypted content data is sent to the electronic paper card so that the electronic paper card can update its content based on the encrypted content data.

2. The content update authentication method according to claim 1, characterized in that, The step of obtaining the first preset key and the content data to be updated corresponding to the UID includes any one of the following: Send the UID to the server and receive the first preset key corresponding to the UID and the content data to be updated sent by the server; Read the first preset key and the content data to be updated that correspond to the UID stored locally in the card slot.

3. The content update authentication method according to claim 1, characterized in that, The step of verifying the response value based on the first preset key, the UID, and the random challenge number to obtain the verification result includes: Based on the first preset key, the UID, and the random challenge number, the expected response value is calculated using a message authentication code algorithm, wherein the message authentication code algorithm is HMAC-SHA256 or AES-CMAC; The expected response value is compared with the actual response value to obtain the verification result.

4. The content update authentication method according to claim 1, characterized in that, After verifying the response value based on the first preset key, the UID, and the random challenge number to obtain the verification result, the method further includes: If the verification result indicates that the verification failed, the first number of authentication failures is accumulated, and an authentication failure notification is sent to the electronic paper card. If the number of first authentication failures reaches a preset first threshold, a lock notification is sent to the server, and the lock notification carries the UID.

5. The content update authentication method according to claim 4, characterized in that, The content update authentication method also includes: In response to receiving an unlock trigger operation for an electronic paper card that is in a locked state, an unlock request is sent to the server, the unlock request carrying the UID; Receive the unlock credential corresponding to the UID sent by the server when the unlock request meets the preset verification conditions; Send an unlock command carrying the unlock credential to the electronic paper card to unlock the electronic paper card.

6. A content update authentication method, characterized in that, Applied to electronic paper cards, wherein the electronic paper card stores a second preset key, the content update authentication method includes: When the card slot and the electronic paper card are in contact communication connection, the UID reading command sent by the card slot is received; The UID of the electronic paper card is read according to the UID reading instruction, and the UID is sent to the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. Receive the random challenge number sent by the card slot; Calculate the response value based on the second preset key, the UID, and the random challenge number, and send the response value to the card slot; Receive encrypted content data sent by the card slot after verifying the response value; A second session key is derived from the UID, the random challenge number, and the second preset key; The encrypted content data is decrypted using the second session key to obtain the content data to be updated; The display content of the electronic paper card is refreshed based on the data to be updated.

7. A content update authentication method, characterized in that, Applied to the server side, the content update authentication method includes: The receiver receives the UID of the electronic paper card sent by the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. Based on the UID, determine the first preset key and the content data to be updated corresponding to the UID; Send the first preset key and the content data to be updated to the card slot.

8. A first content update authentication device, characterized in that, Applied to a card slot, the first content update authentication device includes: The first sending module is used to send a UID reading command to the electronic paper card when the card holder and the electronic paper card are in contact communication connection. The first receiving module is used to receive the UID sent by the electronic paper card according to the UID reading instruction. The UID is an identifier that is factory-fixed by the MCU built into the electronic paper card and does not support rewriting. The acquisition module is used to acquire the first preset key and the content data to be updated corresponding to the UID; The transceiver module is used to generate and send a random challenge number to the electronic paper card, and to receive a response value sent by the electronic paper card. The response value is calculated by the electronic paper card based on the second preset key, the UID, and the random challenge number. The verification module is used to verify the response value based on the first preset key, the UID, and the random challenge number, and obtain the verification result; An encryption module is used to derive a first session key based on the UID, the random challenge number, and the first preset key when the verification result indicates that the verification is successful, and to encrypt the content data to be updated based on the first session key to obtain encrypted content data. The second sending module is used to send the encrypted content data to the electronic paper card so that the electronic paper card can update its content based on the encrypted content data.

9. A second content update authentication device, characterized in that, Applied to electronic paper cards, wherein the electronic paper card stores a second preset key, the second content update authentication device includes: The second receiving module is used to receive the UID reading command sent by the card slot when the card slot and the electronic paper card are in contact communication connection. The reading module is used to read the UID of the electronic paper card according to the UID reading instruction and send the UID to the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and does not support rewriting. The third receiving module is used to receive the random challenge number sent by the card slot; The calculation module is used to calculate a response value based on the second preset key, the UID, and the random challenge number, and send the response value to the card slot; The fourth receiving module is used to receive encrypted content data sent by the card slot after verifying the response value; The derivation module is used to derive a second session key based on the UID, the random challenge number, and the second preset key; The decryption module is used to decrypt the encrypted content data according to the second session key to obtain the content data to be updated; The refresh module is used to refresh the display content of the electronic paper card based on the content data to be updated.

10. A third content update authentication device, characterized in that, Applied to the server side, the third content update authentication device includes: The receiving module is used to receive the UID of the electronic paper card sent by the card slot. The UID is a factory-fixed identifier of the MCU built into the electronic paper card and cannot be rewritten. The determination module is used to determine the first preset key and the content data to be updated corresponding to the UID based on the UID; The sending module is used to send the first preset key and the content data to be updated to the card slot.

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