Chip Private Key Update via Internal Key and Random Numbers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing chip security technologies require returning the chip to the factory for private key updates, consuming resources and potentially compromising security by revealing the private key to a trusted center.
Innovation Solution
A method for generating and updating private keys on the chip using random numbers and an internal key, where the private key is divided into internal and random number components, allowing only the chip to access the update private key, ensuring security and reliability without physical return for maintenance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the chip is returned to the factory for private key update, then the private key can be updated, but it consumes manpower and material resources
Solution Approach 1:
The chip performs self-key generation and self-update without requiring factory intervention. The chip uses its internal key to generate a new private key pair and update its public key locally, enabling autonomous maintenance without returning to the factory.
Solution Approach 2:
The chip pre-stores an internal key in non-volatile memory during manufacturing. This internal key is used to generate both the initial private key and subsequent update private keys, eliminating the need for factory intervention in future updates.
2Reliability
If a trusted center is required to know the updated private key, then the private key can be updated centrally, but it violates the principle that the private key should be known only to the chip, causing potential security hazards
Solution Approach 1:
The patent extracts the random number generation function from the trusted center and places it within the chip itself. The chip generates its own random numbers using a secure random number generator, eliminating the need for the trusted center to know the private key while maintaining update control.
Solution Approach 2:
The internal key acts as an intermediary that enables the chip to autonomously generate private keys without revealing them to external entities. The internal key is stored in non-volatile memory and used to derive both initial and updated private keys through cryptographic operations.
3Ease of operation
If the private key is divided into internal key and random number components, then the chip can update the private key without returning to the factory, but the chip must securely store and manage the internal key
Solution Approach 1:
The private key is segmented into two components: a permanent internal key stored in non-volatile memory and a temporary random number generated during key generation. This segmentation allows the internal key to remain secure while enabling convenient private key updates through random number replacement.
Solution Approach 2:
The random number component is treated as a disposable element that is generated, used for key derivation, and then discarded. The chip generates new random numbers for each key update operation, eliminating the need to manage long-term secrets externally while maintaining security.
Data Source
AI summary
The present disclosure relates to a key generation method applied to a chip storing an internal key, which includes: acquiring (101) a first and a second random number; generating (102) an initial private key of the chip according to the first random number and the internal key, and generating an update private key of the chip according to the second random number and the internal key; generating (103) an initial public key corresponding to the initial private key according to the initial private key, and generating an update public key corresponding to the update private key according to the update private key; and sending (104) the initial public key, the update public key, and the second random number to a server that sends the second random number to the chip when receiving a private key update request of the chip, to trigger a private key update of the chip.