Secure chip key burning method and system

Abstract

The invention provides a secure chip key burning method and system, and the method comprises the steps: a to-be-burnt chip provides and stores a random number, the random number is encrypted through a server public key and then is sent to a server through a local burning computer, the server carries out the decryption to obtain the random number, encrypts a sensitive key, and returns the sensitive key, and the security processor in the chip to be burnt calls the random number and decrypts the random number, and then burns the sensitive key to a chip security storage unit. The system comprises a server, a local burning computer and a to-be-burnt chip, wherein the to-be-burnt chip comprises a security processor, a random number generator, an internal security storage area and a security storage unit. According to the method, the full-link plaintext-free transmission of the key is realized, the risk of human leakage is avoided, the universality is high, the management is efficient, and the method is suitable for chip production scenes with strict requirements on key security.

Description

Technical Field

[0001] This invention relates to the field of chip programming technology, and more specifically, to a secure chip key programming method and system. Background Technology

[0002] Chip keys are the core foundation for ensuring the information security of chips and terminal devices, and their programming process directly determines the security level throughout the chip's lifecycle. During chip manufacturing and application, technologies such as encrypted transmission and access control are necessary to prevent key leakage or tampering during distribution and programming. With the increasing demands for chip security in fields such as the Internet of Things, automotive electronics, and financial payments, the security, controllability, and compatibility of key programming have become core requirements for the development of related technologies.

[0003] Existing chip key programming technologies mostly employ external injection methods, where chip manufacturers or third-party engineers directly generate keys and then program them in plaintext using dedicated equipment. These technologies generally rely on trusted third-party involvement, and during key transmission and sharing across the supply chain, security heavily depends on human oversight and legal constraints, making them highly susceptible to leakage, copying, or tampering. Furthermore, existing programming technologies lack a unified centralized key management mechanism, resulting in complex programming process management, insufficient compatibility, and difficulty in meeting the application requirements of different security levels and scenarios.

[0004] Therefore, there is an urgent need for a chip key security programming solution that can achieve centralized key management and control, end-to-end encrypted transmission, secure isolation within the chip, and strong adaptability, in order to solve the problems of high risk of key leakage, high management cost, insufficient storage security, and limited adaptability in existing technologies. Summary of the Invention

[0005] Based on existing technologies, the objective of this invention is to provide a secure chip key programming method and system that can provide security guarantees for programming sensitive chip keys, and solve the problems of high key leakage risk, high management cost, insufficient storage security and limited adaptability in existing technologies.

[0006] A first aspect of the present invention provides a secure chip key programming method, comprising: The chip to be programmed provides and stores random numbers, and encrypts the random numbers using the server's public key; The security processor inside the chip to be programmed sends the encrypted random number to the local programming computer. The local programming computer sends the encrypted random number to the server; After receiving the encrypted random number, the server decrypts the encrypted random number using the server's private key, which is paired with the server's public key, to obtain the random number. The server uses the random number as the encryption key to encrypt the sensitive key, generates an encrypted sensitive key, and sends the encrypted sensitive key to the local burning computer. The local programming computer transmits the encrypted sensitive key to the security processor; The security processor retrieves the random number as the decryption key, performs a decryption operation on the encrypted sensitive key, and obtains the sensitive key; and The security processor initiates the programming control logic to program the sensitive key into the secure storage unit inside the chip to be programmed.

[0007] Furthermore, the method also includes: Establish a secure connection between the local burning computer and the server.

[0008] Furthermore, the server public key is pre-stored in the internal secure storage area of ​​the chip to be programmed before it leaves the factory, and the server private key is pre-stored in the server.

[0009] Furthermore, the random number is stored in the internal secure storage area of ​​the chip to be programmed.

[0010] Furthermore, the internal secure storage area has an access control mechanism that allows only the secure processor to perform read and write operations.

[0011] Furthermore, the random number is generated by a random number generator inside the chip to be programmed.

[0012] Furthermore, the encryption and / or decryption are symmetric encryption and / or symmetric decryption.

[0013] Furthermore, the local programming computer transmits the encrypted sensitive key to the security processor via a programming tool bus, wherein the programming tool bus type includes EJTAG, SPI, I2C, SWD and / or UART.

[0014] Furthermore, the secure storage unit includes a one-time programmable storage unit (OTP) and / or an electronic fuse (eFuse).

[0015] A second aspect of the present invention also provides a secure chip key programming system for performing the method provided in the first aspect of the present invention, the system comprising: The server is configured to store the sensitive keys to be programmed and has a pre-set private key that matches the server public key in the chip to be programmed. The local programming computer establishes a secure connection with the server via a network and a communication connection with the chip to be programmed via a programming tool bus; and The chip to be programmed includes: A security processor configured to perform random number encryption / decryption operations and secure burning and control of sensitive keys; A random number generator configured to generate random numbers as the symmetric encryption key used for burning the sensitive key; An internal secure storage area, configured to store the random number and allowing only the secure processor to perform read and write operations; and Secure storage units include one-time programmable storage units (OTP) and / or electronic fuses (eFuse).

[0016] The present invention has at least the following beneficial effects: (1) This invention centrally manages sensitive keys through a server, and combines secure connection and double encryption mechanism to achieve plaintext transmission of sensitive keys from distribution to burning, effectively eliminating the risk of interception and tampering during transmission.

[0017] (2) The entire process of key generation, transmission and acquisition does not require human intervention. Even the engineer responsible for burning cannot know the specific content of the sensitive key. It gets rid of the dependence of traditional burning methods on confidentiality laws and avoids the hidden danger of human leakage of keys from the root. It ensures that only the key grantor and the grantee can know the key information, and improves the security and reliability of key management.

[0018] (3) The present invention does not limit the specific types of encryption algorithms, secure connection protocols and programming tool buses. They can be flexibly replaced and adapted according to the compliance requirements, hardware compatibility and security level requirements of actual application scenarios. There is no need to adjust the core architecture of the present invention, which significantly improves the versatility and adaptability of the technical solution and reduces the application cost in different scenarios.

[0019] (4) This invention centrally stores and distributes sensitive keys through a server, which can uniformly verify the legitimacy of the burning request, facilitate the full control and traceability of the key burning process, avoid the management chaos caused by the key flowing through multiple links, improve the management efficiency of key distribution and burning, and thus adapt to the application needs of large-scale chip production burning scenarios.

[0020] In summary, this invention improves the security, reliability, and flexibility of chip key programming from multiple dimensions, including transmission links, storage protection, and efficiency of human intervention management. It effectively solves the problems of traditional programming methods, such as reliance on human constraints, insufficient security protection, and poor compatibility. Based on its high security level and wide applicability, this invention can be widely applied in chip manufacturing scenarios with strict key security requirements, such as IoT security chips, automotive electronic control chips, financial payment chips, industrial control chips, and government-specific chips. Attached Figure Description

[0021] To further illustrate the advantages and other features of the various embodiments of the present invention, a more specific description of the embodiments of the present invention will be presented with reference to the accompanying drawings. It is understood that these drawings depict only typical embodiments of the invention and are therefore not intended to limit its scope. In the drawings, identical or corresponding parts will be indicated by the same or similar reference numerals for clarity.

[0022] Figure 1 A flowchart of a chip key programming method according to one embodiment of the present invention is shown.

[0023] Figure 2 A chip key programming system according to one embodiment of the present invention is shown.

[0024] List of reference numerals 100 Chip Key Programming System 101 Server 102 Local burning computer 103 Chips to be programmed Detailed Implementation It should be noted that the components in the various figures may be shown exaggeratedly for illustrative purposes and are not necessarily to scale. In each figure, the same reference numerals are used for components that are identical or have the same function.

[0025] In this invention, the various embodiments are merely intended to illustrate the solutions of the invention and should not be construed as limiting.

[0026] In this invention, unless otherwise specified, the quantifiers “a” and “one” do not exclude scenarios involving multiple elements.

[0027] It should also be noted that, in the embodiments of the present invention, only a portion of the components or parts may be shown for clarity and simplicity. However, those skilled in the art will understand that, under the teachings of the present invention, necessary components or parts can be added as needed for specific scenarios. Furthermore, unless otherwise stated, features in different embodiments of the present invention can be combined with each other. For example, a feature in the second embodiment can replace a corresponding or functionally identical or similar feature in the first embodiment, and the resulting embodiment will also fall within the scope of disclosure or description of this application.

[0028] It should also be noted that within the scope of this invention, the terms "same", "equal", and "equal to" do not mean that the two values ​​are absolutely equal, but allow for a certain reasonable error. In other words, the terms also cover "substantially the same", "substantially equal", and "substantially equal to".

[0029] In this invention, the modules of the system according to the invention can be implemented using software, hardware, firmware, or a combination thereof. When a module is implemented using software, its function can be implemented through computer program flow. For example, the module can be implemented using code segments (such as code segments in languages ​​like C and C++) stored in a storage device (such as a hard disk, memory, etc.), wherein the corresponding function of the module can be implemented when the code segment is executed by a processor. When a module is implemented using hardware, its function can be implemented by setting a corresponding hardware structure. For example, the module's function can be implemented by hardware programming a programmable device such as a field-programmable gate array (FPGA), or by designing an application-specific integrated circuit (ASIC) that includes multiple transistors, resistors, capacitors, and other electronic devices. When a module is implemented using firmware, the module's function can be written into a read-only memory such as an EPROM or EEPROM in the form of program code, and the corresponding function of the module can be implemented when the program code is executed by a processor. In addition, some functions of the module may need to be implemented by separate hardware or by working in cooperation with the hardware. For example, the detection function is implemented by a corresponding sensor (such as a proximity sensor, accelerometer, gyroscope, etc.), the signal transmission function is implemented by a corresponding communication device (such as a Bluetooth device, infrared communication device, baseband communication device, Wi-Fi communication device, etc.), the output function is implemented by a corresponding output device (such as a display, speaker, etc.), and so on.

[0030] Furthermore, the numbering of the steps in the methods of the present invention does not limit the execution order of the method steps. Unless otherwise specified, the method steps may be executed in different orders.

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0032] Figure 1 A flowchart of a chip key programming method according to one embodiment of the present invention is shown.

[0033] like Figure 1 As shown, in one embodiment of the present invention, the chip key secure programming method includes the following steps: Step S100: The distribution process of sensitive keys is centrally managed in a preset key distribution server. The server is configured to store the sensitive keys to be programmed into the chip, realizing centralized management and secure storage of the keys, and preventing unauthorized access or leakage of the keys during the distribution process.

[0034] Step S200: The local burning computer establishes an end-to-end secure connection with the server. The secure connection is configured to ensure the confidentiality, integrity, and tamper-proof nature of subsequent encrypted data transmission. The specific communication protocol used for the secure connection is not limited and can be adapted to any existing or subsequently developed communication protocol with encrypted transmission capabilities (such as TLS / SSL protocol connections, IPsec VPN connections, and / or SSH protocol connections, etc.), as long as the security requirements for data transmission are met.

[0035] Step S300: The security processor (Security CPU) built into the chip to be programmed actively reads the random number generated in real time by the hardware random number generator integrated inside the chip to be programmed, and directly determines the random number as the Advanced Encryption Standard (AES) symmetric encryption key used in the subsequent sensitive key encryption and decryption process, ensuring the dynamic generation characteristics of the AES key and avoiding the security risks brought about by the fixed key.

[0036] In step S400, the security processor of the chip to be programmed calls the server public key pre-stored in the secure storage area inside the chip to perform asymmetric encryption on the random number generated in the previous step, obtaining an encrypted random number. Simultaneously, the security processor stores the unencrypted original random number in a preset secure storage area inside the chip. This secure storage area has a strict access control mechanism, allowing only the security processor itself to perform read and write operations, and prohibiting access by other functional modules of the chip (including the main CPU).

[0037] Step S500: The security processor of the chip to be programmed sends the encrypted random number, which is encrypted with the server's public key, to the local programming computer through the communication interface between the chip and the local programming computer. This communication interface is a regular data transmission interface between the chip and the local programming computer. Its specific type can be consistent with or independently set with the bus of the subsequent programming tool. Its core is used to complete the relay transmission of encrypted random number data.

[0038] Step S600: After successfully receiving the encrypted random number sent by the security processor of the chip to be programmed, the local programming computer forwards the encrypted random number to the server in its entirety through the secure connection established between the computer and the server. During the forwarding process, the encryption characteristics of the secure connection are relied upon to ensure that the encrypted random number will not be intercepted and / or tampered with.

[0039] In step S700, after receiving the encrypted random number data forwarded by the local programming computer, the server calls its own private key, which is paired with the aforementioned public key, to perform an asymmetric decryption operation on the encrypted random number, restoring the original random number. Subsequently, the server uses the decrypted random number as the AES symmetric encryption key to perform AES encryption on the sensitive key to be programmed into the chip, generating an encrypted sensitive key, and sends the encrypted sensitive key to the local programming computer through a secure connection.

[0040] In step S800, after receiving the encrypted sensitive key sent by the server, the local programming computer accurately transmits the encrypted sensitive key to the security processor of the chip to be programmed through a preset programming tool bus. In specific embodiments of the present invention, the specific type of programming tool bus is not limited, and any suitable chip programming bus type such as EJTAG, SPI, I2C, SWD, and UART can be selected, as long as the stability and adaptability requirements of data transmission are met.

[0041] In step S900, after the chip's security processor receives the encrypted sensitive key transmitted by the local programming computer through the programming tool bus, it retrieves the random number previously stored in the secure storage area inside the chip to be programmed. Using the random number as the AES decryption key, it performs a decryption operation on the encrypted sensitive key data to restore the original sensitive key data to be programmed. After the decryption verification is successful, the security processor starts the programming control logic inside the chip and programs the restored original sensitive key data into the chip's preset one-time programmable storage unit (OTP) or electronic fuse (eFuse) to complete the secure programming operation of the sensitive key.

[0042] In one embodiment of the present invention, the Advanced Encryption Standard (AES) is used to perform symmetric encryption and / or decryption of the sensitive key. In other embodiments of the present invention, other symmetric encryption algorithms, such as the Chinese national standard SM4 or DES, may also be used to perform symmetric encryption and / or decryption of the sensitive key.

[0043] In one embodiment of the present invention, the server public key is pre-stored in the internal secure storage area of ​​the chip to be programmed before it leaves the factory, and the server private key is pre-stored in the server before the chip to be programmed leaves the factory.

[0044] In one embodiment of the present invention, an end-to-end secure connection is established between the local programming computer and the server. In other embodiments of the present invention, other forms of secure connection may be used, such as the local programming computer establishing a secure connection with the server through a hardware encryption gateway, wherein the hardware encryption gateway independently performs data encryption and / or decryption and authentication, and the local programming computer only forwards the encrypted data.

[0045] Figure 2 A chip key programming system according to one embodiment of the present invention is shown.

[0046] like Figure 2 As shown, in one embodiment of the present invention, a chip key programming system is also proposed, the chip key programming system 100 comprising: Server 101 is configured to store the sensitive key to be programmed and has a pre-set server private key that matches the server public key in the chip 103 to be programmed. The local programming computer 102 establishes a secure connection with the server 101 via a network and a communication connection with the chip to be programmed 103 via a programming tool bus; and The chip 103 to be programmed includes a security processor, a random number generator, an internal security storage area, and a security storage unit.

[0047] In one embodiment of the present invention, the security processor is configured to perform random number encryption / decryption operations and secure programming control of sensitive keys. In a specific embodiment of the present invention, the security processor reads a random number generated by a random number generator and determines it as the symmetric encryption key used for sensitive key encryption / decryption. It then calls a server public key preset in the chip to be programmed to perform asymmetric encryption on the random number and sends it to the local programming computer. The processor receives the encrypted sensitive key transmitted by the local programming computer through the programming tool bus, retrieves a random number stored in the internal secure storage area to decrypt it, and initiates the programming control logic to program the decrypted sensitive key into the secure storage unit.

[0048] In one embodiment of the present invention, a random number generator is configured to generate random numbers as symmetric encryption keys used for burning the sensitive key.

[0049] In one embodiment of the invention, an internal secure storage area is configured to store the random number and allow only the secure processor to perform read and write operations.

[0050] In one embodiment of the invention, the type of secure storage unit includes one-time programmable storage unit (OTP) and / or electronic fuse (eFuse).

[0051] Although various embodiments of the invention have been described above, it should be understood that they are presented by way of example only and not as limitations. It will be apparent to those skilled in the art that various combinations, modifications, and alterations can be made without departing from the spirit and scope of the invention. Therefore, the breadth and scope of the invention disclosed herein should not be limited by the exemplary embodiments disclosed above, but should be defined solely by the appended claims and their equivalents.

Claims

1. A secure chip key programming method, characterized in that, include: The chip to be programmed provides and stores random numbers, and encrypts the random numbers using the server's public key; The security processor inside the chip to be programmed sends the encrypted random number to the local programming computer. The local programming computer sends the encrypted random number to the server; After receiving the encrypted random number, the server decrypts the encrypted random number using the server's private key, which is paired with the server's public key, to obtain the random number. The server uses the random number as the encryption key to encrypt the sensitive key, generates an encrypted sensitive key, and sends the encrypted sensitive key to the local burning computer. The local programming computer transmits the encrypted sensitive key to the security processor; The security processor retrieves the random number as the decryption key, performs a decryption operation on the encrypted sensitive key, and obtains the sensitive key; as well as The security processor initiates the programming control logic to program the sensitive key into the secure storage unit inside the chip to be programmed.

2. The method according to claim 1, characterized in that, The method further includes: Establish a secure connection between the local burning computer and the server.

3. The method according to claim 1, characterized in that, The server public key is pre-stored in the internal secure storage area of ​​the chip to be programmed before it leaves the factory, and the server private key is pre-stored in the server.

4. The method according to claim 1, characterized in that, The random number is stored in the internal secure storage area of ​​the chip to be programmed.

5. The method according to claim 3 or 4, characterized in that, The internal secure storage area has an access control mechanism that allows only the secure processor to perform read and write operations.

6. The method according to claim 1, characterized in that, The random number is generated by a random number generator inside the chip to be programmed.

7. The method according to claim 1, characterized in that, The encryption and / or decryption are symmetric encryption and / or symmetric decryption.

8. The method according to claim 1, characterized in that, The local programming computer transmits the encrypted sensitive key to the security processor via a programming tool bus, wherein the programming tool bus type includes EJTAG, SPI, I2C, SWD and / or UART.

9. The method according to claim 1, characterized in that, The secure storage unit includes a one-time programmable storage unit (OTP) and / or an electronic fuse (eFuse).

10. A secure chip key programming system, characterized in that, The system for performing the method of any one of claims 1-9, the system comprising: The server is configured to store the sensitive keys to be programmed and has a pre-set private key that matches the server public key in the chip to be programmed. The local programming computer establishes a secure connection with the server via a network and a communication connection with the chip to be programmed via a programming tool bus; and The chip to be programmed includes: A security processor configured to perform random number encryption / decryption operations and secure burning and control of sensitive keys; A random number generator configured to generate random numbers as the symmetric encryption key used for burning the sensitive key; An internal secure storage area, configured to store the random number and allowing only the secure processor to perform read and write operations; and Secure storage units include one-time programmable storage units (OTP) and / or electronic fuses (eFuse).

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