Trusted Execution Environment Manager Authentication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional techniques for implementing a trusted execution environment (TEE) in computing devices are inadequate, as they often rely on specific CPU cores or operating systems, fail to effectively control security-sensitive resources, and are vulnerable to threats such as stack and cache manipulations, leading to inadequate security assurances from a system-wide perspective.
Innovation Solution
A TEE manager is introduced that authenticates privileged software and enables secure access to security-sensitive hardware by using a password-based authentication mechanism, which is immune to attacks and operates independently of specific CPU cores or operating systems, ensuring secure switching between restricted and trusted execution environments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional techniques are used to implement TEE, then specific CPU cores or operating systems can provide some security features, but the solution becomes enslaved to a specific CPU core and operating system, reducing system versatility
Solution Approach 1:
The patent creates a universal TEE manager that can operate across different CPU cores and operating systems by implementing a standardized authentication interface. The TEE manager uses generic CPU features (instruction fetching, execution, password comparison) rather than relying on specific CPU vendor features, making it adaptable to various hardware platforms and operating systems while maintaining security functionality.
2Ease of operation
If conventional techniques are used to control security-sensitive resources, then some access control is provided, but the techniques are vulnerable to attacks such as stack and cache manipulations, reducing security reliability
Solution Approach 1:
The patent implements preliminary authentication of trusted software before allowing access to security-sensitive resources. The TEE manager verifies passwords and authenticates the privileged routine before enabling security-sensitive hardware, ensuring that only verified trusted software can access protected resources. This preliminary verification prevents attacks by establishing security credentials before resource access.
Solution Approach 2:
The TEE manager acts as an intermediary between the CPU core and security-sensitive hardware resources. It mediates access by controlling whether security-sensitive hardware is enabled based on authentication results, providing a security layer that is independent of the operating system and protected against manipulation attacks.
3Reliability
If features are built into a CPU core to control privileged mode, then some security distinction is provided, but the features do not extend outside the CPU core, preventing system-wide security control
Solution Approach 1:
The patent segments security control into a dedicated TEE manager component that operates independently from the CPU core's privileged mode features. The TEE manager is a separate software module that can control multiple security-sensitive resources across the system, extending security control beyond what a single CPU core can provide while maintaining the privileged mode distinction.
Data Source
AI summary
A computing device (10) includes a trusted execution environment (TEE) manager (40) that manages a switchover from non-trusted software (116) to trusted software (118). The TEE manager (40) includes memory (90) configured to store password-bearing, immediate-operand instructions (54). At the point of switching between the non-trusted software (116) and the trusted software (118) the memory (90) may be accessed as instruction fetches, and its contents fetched into a CPU core (24) as instructions. Immediate-operand portions (60) of the immediate-operand instructions (54) provide passwords, which are written back into guess registers (80) within the TEE manager (40). When a predetermined relationship between the instructions (54) and guesses in guess registers (80) is identified, actual execution of the immediate-operand instructions (54) is verified, the TEE mode of operation is signaled, and security-sensitive hardware (44) is enabled for use by a privileged routine (42) portion of the trusted software (118).