Improperly Preserved Integrity of Hardware Configuration State During a Power Save/Restore Operation
Improperly Preserved Integrity of Hardware Configuration State During a Power Save/Restore Operation
CWE-1304
Short description
Extended description
Best practices to prevent this CWE
Phase: Architecture and Design
Inside the IP, incorporate integrity checking on the configuration state via a cryptographic hash. The hash can be protected inside the IP such as by storing it in internal registers which never lose power. Before powering down, the IP performs a hash of the configuration and saves it in these persistent registers. Upon restore, the IP performs a hash of the saved configuration and compares it with the saved hash. If they do not match, then the IP should not trust the configuration.
Phase: Integration
Outside the IP, incorporate integrity checking of the configuration state via a trusted agent. Before powering down, the trusted agent performs a hash of the configuration and saves the hash in persistent storage. Upon restore, the IP requests the trusted agent validate its current configuration. If the configuration hash is invalid, then the IP should not trust the configuration.
Phase: Integration
Outside the IP, incorporate a protected environment that prevents undetected modification of the configuration state by untrusted agents. Before powering down, a trusted agent saves the IP's configuration state in this protected location that only it is privileged to. Upon restore, the trusted agent loads the saved state into the IP.
