Re: [ros-dev] Security policy for FAT partition driver?

[Robert Shearman]

Phillip Susi wrote:

>   How exactly are xattrs stored on disk?  Is it possible
> and efficient 
>  to store a dozen xattrs on a file of various sizes from 1kb to several 
>  MB?  How would you reconcile the two different sets of owner and 
>  access information associated with the file?  For instance, if someone 
>  creates a file on the partition from Linux, then you mount it with 
>  ROS, who owns the file?  Who has access to it?  Linux would only place 
>  some meaningless uid and chmod mask in the inode, so how would ROS 
>  come up with a sensible security descriptor for the file when one does 
>  not already exist?
>
>  These are the kinds of problems that make attempts for ReactOS to 
>  share a unix filesystem ( and vice versa ) kludgey at best. 

You get the same problems when sharing an NTFS filesystem on a dual-boot 
system or when moving one between computers, unless the SIDs are well-known.
I would suggest you check out the Samba presentation at the following 
URL for information on how Samba4 does NTFS->Unix permissions conversion 
so you are not stabbing in the dark:
http://wiki.winehq.org/WineConf

The problem you are describing has already been solved by them in a 
slightly-not-kludgey way.

Rob