SoC Secure Domain Processing with Dual Security Attributes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mobile device systems face challenges in securely processing high-quality contents due to vulnerabilities in their open OS structure and code, making it difficult to block unauthorized access and maintain security while minimizing performance overhead and development costs.
Innovation Solution
A system-on-chip configuration that sets dual security attributes for hardware blocks, allowing non-secure access for software from the non-secure domain while maintaining secure access for sensitive operations, using memory management units to limit access and minimize switching between secure and non-secure domains.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If DRM protection is implemented using TrustZone with open OS structure, then contents security is provided, but security against unlawful access deteriorates because the open OS structure and code make it relatively easy to attack secure contents
Solution Approach 1:
The system is divided into secure and non-secure domains with distinct processing paths. Secure contents are processed by a secure processor in the secure domain, while non-secure applications run in the non-secure domain. This segmentation prevents non-secure code from accessing or attacking secure contents, resolving the vulnerability issue while maintaining security.
Solution Approach 2:
The secure processing functionality is extracted into a separate secure processor and secure domain, isolated from the main non-secure OS. This extraction removes the attack surface that exists in traditional TrustZone implementations where secure code runs on the same processor as non-secure code, making the system resistant to attacks from the open OS structure.
2Adaptability or versatility
If frequent switching between secure and non-secure domains is performed to process contents, then flexibility in handling different security levels is improved, but performance overhead increases due to the switching operations
Solution Approach 1:
The system dynamically determines the security level of each content based on its properties, and automatically routes it to the appropriate processor without requiring manual switching. This dynamic adaptation maintains security flexibility while eliminating the performance overhead of explicit domain switching operations.
Solution Approach 2:
The content itself carries security attribute information that enables the system to automatically determine the appropriate processing domain. The content essentially serves its own security routing needs, eliminating the need for external switching control and reducing performance overhead.
3Reliability
If significant modifications are made to hardware structure to achieve high security level, then security performance is improved, but development cost increases
Solution Approach 1:
The secure processor is designed as a universal processing unit that can handle various types of secure contents and operations. This multi-functionality reduces the need for specialized hardware modifications for different security scenarios, thereby lowering development costs while maintaining high security levels.
Solution Approach 2:
A secure processor acts as an intermediary between secure contents and the non-secure environment. This intermediary approach provides high security without requiring extensive modifications to the existing hardware structure, as the secure processor can be integrated as a separate unit that interfaces with the existing system through controlled channels.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A mobile device is provided which includes a working memory having a memory area divided into a secure domain and a non-secure domain; and a system-on-chip configured to access and process contents stored in the secure domain. The system-on-chip includes a processing unit driven by at least one of a secure operating system and a non-secure operating system; at least one hardware block configured to access the contents according to control of the processing unit comprising a master port and a slave port which are set to have different security attributes; at least one memory management unit configured to control access of the at least one hardware block to the working memory; and an access control unit configured to set security attributes of the slave port and the master port or an access authority on each of the secure domain and the non-secure domain of the working memory.