Firmware Source Verification Using OTP Identity and Root of Trust
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Firmware loaded by unauthorized entities during device manufacturing can lead to unauthorized access and system malfunction, compromising device security and integrity.
Innovation Solution
Implementing a Root of Trust (ROT) firmware that verifies the identity of the manufacturing firmware by comparing it with an identity stored in One Time Programmable (OTP) memory, ensuring only authorized firmware is executed and generating device secret keys only if the identity matches, thereby preventing unauthorized access.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If firmware is loaded during device manufacturing without identity verification, then device manufacturing and firmware updates are simplified and faster, but device security and firmware integrity are compromised due to unauthorized access
Solution Approach 1:
The patent applies preliminary action by storing the firmware provider identity in OTP memory during device manufacturing before the firmware is actually loaded and executed. This pre-established identity record enables later verification without slowing down the firmware loading process, as the verification can be performed quickly by comparing against the pre-stored identity.
Solution Approach 2:
The patent introduces an intermediary verification mechanism using OTP memory to store and compare firmware provider identities. This intermediary layer acts as a trusted mediator between the firmware loading process and security verification, allowing automated identity checking without requiring complex manual verification procedures.
2Reliability
If identity verification is implemented for firmware providers, then device security and firmware integrity are improved, but device complexity and manufacturing process complexity increase
Solution Approach 1:
The patent segments the security verification function into a separate, dedicated component using OTP memory to store firmware provider identities. This segmentation isolates the verification logic from the main firmware loading process, reducing overall system complexity by creating a modular, independent verification subsystem that can be implemented as a simple compare operation.
Solution Approach 2:
The patent uses OTP (One Time Programmable) memory to store firmware provider identities, which is a simple, non-reconfigurable storage medium. This disposable-like approach to identity storage simplifies the verification system, as OTP memory provides secure, write-once storage without requiring complex update or management mechanisms.
3Ease of operation
If secret keys are generated for unauthorized firmware, then firmware functionality is maintained, but unauthorized access to device data and system malfunction occur
Solution Approach 1:
The patent applies preliminary anti-action by implementing identity verification before secret key generation. The system proactively prevents unauthorized firmware from obtaining secret keys by checking the firmware provider identity against the OTP-stored identity in advance, thereby blocking unauthorized access before it can occur rather than reacting to it later.
Solution Approach 2:
The patent implements a feedback mechanism where the secret key generation process is conditioned on the result of identity verification. If the firmware provider identity matches the stored identity, secret keys are generated; otherwise, generation is blocked. This feedback loop ensures that only authorized firmware can obtain the keys needed for execution, creating a security gate without preventing legitimate operation.
Data Source
AI summary
Examples described herein relate to tracking identification of firmware providers to identify unauthorized firmware providers. For example, prior to sharing device secret data with a firmware provider, circuitry can store an identification of the firmware provider in one time programmable (OTP) memory to record the identifier of the firmware provider.