SWRU455M February 2017 – October 2020 CC3120 , CC3120MOD , CC3130 , CC3135 , CC3135MOD , CC3220MOD , CC3220MODA , CC3220R , CC3220S , CC3220SF , CC3230S , CC3230SF , CC3235MODAS , CC3235MODASF , CC3235MODS , CC3235MODSF , CC3235S , CC3235SF
This chapter describes the capabilities of the file system and the host interface, and provides usage recommendation.
The SimpleLink Wi-Fi device maintains a nonvolatile file system in which the data is stored on an external serial flash (through SPI). The file system provides the ability to organize data and access resources using a simple host interface.
The SimpleLink Wi-Fi networking subsystem uses the file system to store the system configuration files and for storing the service pack. In CC32xx devices, the storage is also used to store the host application.
The file system provides features to protect the stored files from manipulation by unknown or malicious users, such that the files cannot be read or modified freely by third parties.
In addition, the SimpleLink Wi-Fi device supports cloning protection; moving or cloning a SFLASH that was written by one device to other does not work. One device cannot use a file system or read secure files created by another device.
File integrity monitoring is an internal process that performs the act of validating the integrity of the file system and stored files, using a verification method between the current file state and the known, good baseline. This comparison method involves calculating a known cryptographic checksum of the original baseline of the file, and comparing it with the calculated checksum of the current state of the file.
The SimpleLink internal process for software tamper detection monitors the use of the file and detects attempts to tamper the file system; it detects operations such as accessing the file without the correct credentials, or the writing of the file by an unauthenticated user.
The SimpleLink Wi-Fi device also provides a recovery mechanism; it enables to rollback the system configuration to the factory settings.