*FAT32 modifications for Android***

Author: Gaurav Tungatkar, Nikhil Talpalikar

Description: Modifications to the vfat driver in the Linux kernel module to add a permissions layer to FAT32. This project tries to implement unix style permissions on top of FAT32.

Rationale: Android based smartphones increasingly use FAT32 formatted SD cards for storing all sorts of data. With virtually no protection provided by FAT32, this opens up security holes for data corruption. Adding unix style permissions is useful here because in Android, every application gets a different user id. Each application can be thought of as a user and unix style user-group-world permissions can help enforce separation between applications.

Design: Each folder has a hidden ".permissions" file which stores the mode and uid, gid information for each file in that folder. Hacks in file open, to read this special file and file in the permissions. chmod, chown supported, making changes to entries in the ".permissions" file. See demo video.