Authentication Counter Protection Against Power-Off Attacks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing authentication methods in electronic devices are vulnerable to malicious attacks, particularly power-off attacks that can manipulate failure counters, compromising the security of authentication processes.
Innovation Solution
A protection mechanism that involves rewriting specific data elements into memory cells based on the success or failure of authentication attempts, using a non-volatile memory to secure the incrementation of a failure counter, and ensuring resilience against power-off attacks by verifying the state of these data elements upon restart.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a failure counter is used to track authentication failures, then authentication security is improved, but the system becomes vulnerable to power-off attacks that can manipulate the counter
Solution Approach 1:
The patent divides the memory into multiple pairs of memory cells, with each pair dedicated to storing specific data elements (first data element, second data element, third data element, fourth data element). This segmentation allows the failure counter and authentication state to be distributed across multiple memory locations, making it resistant to power-off attacks that target single memory cells. The current active pair indicator further segments the control logic, enabling reliable state tracking without vulnerability to power manipulation.
2Reliability
If memory cells are rewritten based on authentication success or failure, then authentication integrity is improved, but device complexity increases
Solution Approach 1:
The patent applies local quality by differentiating the treatment of memory cells based on their specific roles. The first and second memory cells store different data elements (first data element vs. second data element), and the third and fourth memory cells store different data elements (third data element vs. fourth data element). This localized differentiation allows the system to maintain authentication integrity through selective rewriting while managing complexity through clear, role-based memory organization. Each memory cell has a specific function, simplifying the overall management despite the multiple cells involved.
Data Source
AI summary
A device executes an authentication process protected by an authentication counter that is incremented in case of an authentication failure. The incrementation of the counter is protected against unexpected device power-off or power-off attacks. A non-volatile memory is divided into pairs of cells. The protecting includes writing a fixed value D into an active pair of two consecutive cells. As long as successful authentications occur, the content of the first cell is overwritten by a random value. When a failed authentication occurs, the content of the second cell is overwritten by a random value and the next two consecutive cells are written with the fixed value D. Those cells form the active pair and the protection process is repeated. This mechanism facilitates preventing the lack of incrementation of the authentication counter in case of unexpected device power-off during the processing of a failed authentication.