Command Source Verification in Processor Memory
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In current processor architectures, external entities may have unrestricted access to memory resources, leading to security concerns where lower-privileged code can inadvertently or maliciously access and modify highly privileged memory areas, potentially causing information leakage and privilege escalation, as they lack verification of the command source's privilege level.
Innovation Solution
Implementing a predefined path and protocol for command source verification, where commands must follow a specific sequence and originate from a predefined location within highly privileged memory to be executed, ensuring that only legitimate commands from highly privileged modes are processed, thereby preventing unauthorized access and data corruption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If external entities are granted unrestricted access to memory resources for efficient command processing, then productivity is improved, but security reliability deteriorates as lower-privileged code can access and modify highly privileged memory areas
Solution Approach 1:
The patent segments memory resources into distinct privilege levels (first privilege level for highly privileged code, second privilege level for lower privileged code) and implements separate command buffers for each level. This segmentation prevents lower-privileged code from accessing highly privileged memory areas while maintaining efficient command processing for authorized operations.
Solution Approach 2:
The patent introduces an intermediary verification mechanism that checks the privilege level of command sources before allowing access to memory resources. This intermediary layer validates whether commands originate from authorized privilege levels, blocking unauthorized access attempts while permitting legitimate operations to proceed efficiently.
2Reliability
If command source verification is implemented to prevent unauthorized access, then security reliability is improved, but device complexity increases due to additional verification protocols and predefined paths
Solution Approach 1:
The patent establishes predefined paths and verification protocols during system initialization before normal operation begins. By pre-configuring authorized command sources, memory mappings, and verification rules, the system eliminates the need for complex runtime decision-making, reducing operational complexity while maintaining strong security verification.
Solution Approach 2:
The patent applies verification protocols selectively based on local conditions - specifically, verification is applied only at the boundary between different privilege levels and for commands accessing highly privileged memory areas. Ordinary operations within the same privilege level proceed without verification, minimizing the complexity overhead of security checks.
Data Source
AI summary
Example implementations relate to command source verification. An example device can include instructions executable to send a command via a predefined path to a predefined location within a memory resource storing instructions executable to verify a source of the command using a predefined protocol and execute the command in response to the source verification.