Fedora 11: moving to posix file capabilities?

[seth vidal]

On Thu, 2008-10-30 at 20:41 +0200, Panu Matilainen wrote:
> On Thu, 30 Oct 2008, seth vidal wrote:
> 
> > On Thu, 2008-10-30 at 20:25 +0200, Panu Matilainen wrote:
> >> On Wed, 29 Oct 2008, Steve Grubb wrote:
> >>
> >>> On Wednesday 29 October 2008 06:37:32 Panu Matilainen wrote:
> >>>> We have kernel support for storing capabilities on filesystem since 2.6.24
> >>>> and recent libcap, both in F9 already.
> >>>
> >>> And we have also been busy updating everything else to support this:
> >>>
> >>> https://bugzilla.redhat.com/show_bug.cgi?id=449984
> >>
> >> Ah, thanks for the pointer.
> >>
> >>>
> >>>> I just committed file capability support to rpm.org HEAD, filling in the
> >>>> final(?) missing piece. Capability support is not going to be in rpm 4.6.0
> >>>> but no reason they can't be pulled into 4.6.1 which is easily in F11
> >>>> timeframe.
> >>>
> >>> We tried to support this in F-10 by having a test run with ping. We figured
> >>> that is a simple well defined app that could be used as a test subject. We
> >>> opened bz 455713 to document the change over. Turns out that people compile
> >>> their own kernels and do not necessarily turn this on. So, what do we do in
> >>> that case?
> >>
> >> People compiling their own kernels can hose their systems more
> >> dramatically than this...
> >>
> >>>
> >>>> Are we ready to start considering moving away from SUID bits to
> >>>> capabilities, in Fedora 11 maybe?
> >>>
> >>> We tried and got turned back. How does rpm work on kernels that do not support
> >>> file capabilities? I'd like to see us get past the initial objections so that
> >>> we can start removing some of the setuid bits.
> >>
> >> Right now, installation of a package using capabilities will fail entirely
> >> if kernel/filesystem doesn't support setting capabilities. Packages with
> >> capabilities in them require rpmlib(FileCaps) feature, which rpm currently
> >> provides if built with libcap support. It could (and probably should,
> >> anyway) be made into a run-time tested feature, so that you'll get
> >> something like this if running on kernel with no capability support:
> >>
> >> error: Failed dependencies:
> >>  	rpmlib(FileCaps) <= 4.6.1-1 is needed by ...
> >
> > Except nothing really watches those rpmlib() deps much at all, does it?
> 
> Rpm itself does, so unless you use --nodeps (or the API equivalent of 
> that) it'll get caught before transaction starts.

but after you've downloaded everything. And what provides those things
these days?

-sv