Re: [PATCH] libxl: assigned a default ssid_label (XSM label) to guests

[Ian Campbell <ian.campbell@citrix.com>]

On Fri, 2015-05-15 at 13:09 -0400, Daniel De Graaf wrote:
> > I'd be inclined to go the other way and either have a default ssid for
> > the DM or to fail if one isn't given (the latter would probably happen
> > anyway due to enforcement?).
> 
> Yes, it would probably fail at xc_domain_set_target in enforcing mode.
> 
> > Sounds like the default ssidref should be either ~= domU_t of domHVM_t
> > depending on the type of domain? (domU_t is really domPV_t?)
> 
> The domU_t type also works for HVM domains with the device model in dom0.
> 
> Looking at the problem again, I think a second initial SID for the device
> model would be preferable, removing domHVM_t completely.  There are already
> other example types in the policy for domains that do not use a device model
> (isolated_domU_t is probably the best example), and the result more closely
> matches the permissions used in the hypervisor without XSM enabled.

I'm aroundabout half sure what you are proposing here, but I trust it
makes sense ;-).

I think for now I will investigate using a default ssid for all domains,
which AIUI from above will work out of the box with PV guests and HVM
ones which have qemu in dom0.

For the stubdom case I think I'll leave it to you to change the default
policy, at which point I'll be happy to extend things to a default ssid
for stubdom too.

Ian.