devkit-disks: Allowed ntfs-3g mount options

[David Zeuthen]

On Mon, 2009-06-15 at 09:09 -0400, Matthias Clasen wrote:
> On Mon, Jun 15, 2009 at 8:08 AM, Martin Pitt<martin.pitt at ubuntu.com> wrote:
> 
> >
> > Dropping the mount options from the UI entirely stops people from
> > being able to share their USB hard disk with other users on the
> > system, though. There might be a few other use cases, but this one
> > seems to be the most obvious to me.
> 
> Sharing devices seems like something that should be properly designed
> as a feature, not exposed in some backwards way via obscure mount
> options...

Right. Keep in mind that the Mount() method supports the 'remount'
option so presumably if you wanted to share mounts you could hook into
that and then do the right thing e.g. change dmask for FAT mounts. For
example you could write a Nautilus extension that exposes this either
via a Cluebar (like the CD burner one) or menu options. But I think it's
going to be hard to implement anyway, e.g. you can't really do this for
ext3/ext4 since it involves mocking around with permissions on the root
folder.

As Matthias says, sharing "stuff" [1] between desktop sessions will
probably require a lot of up-front design work. My gut feeling is that
sharing a personal thing like a USB drive is not part of this. It's
probably easier for sessions to exchange objects via some other protocol
e.g. instant messaging or a shared folder. I think both Windows and OS X
have something like shared folders.

One interesting question is what the user experience for fast user
switching should be.... today a USB device mounted in session A is not
accessible if you switch into session B on the same console. That's
probably a bug but you can really also argue it's not...

So right now the way things work is that, in session B, you need to auth
as the admin to unmount the device mounted in session A. Then you can
mount it yourself. I think this is probably good enough as it really is
an oddball case and it's good to err on the side of not disclosing /
leaking information by default.

Suggestions welcome.

    David


[1] : With "stuff" meaning things that people fundamentally wants to
share. This is typically documents or even high-level objects like
contacts or messages, not so much an entire file system that happens to
be on a USB gizmo.