Re: xattrs support

[Guillem Jover <guillem@debian.org>]

Hi!

On Fri, 2014-09-12 at 13:44:03 -0400, Mimi Zohar wrote:
> On Fri, 2014-09-12 at 12:12 +0400, Dmitry Falko wrote: 
> > I have a question on support xattrs in dpkg-dep. As far as I know in 
> > version 1.27.1 (Ubuntu 14.04) supports the creation of tar archives 
> > preserving extended attributes, perhaps it makes sense to add ability to 
> > create packages containing files with extended attributes. May be 
> > special options?
> 
> I'm very interested in having xattrs included in deb packages.  Which
> xattrs in particular are you interested in?  Part of the problem is that
> fake-root creates the directory structure, but wouldn't be able to copy
> the security xattrs. Reading security xattrs is permitted, but writing
> security xattrs requires privilege.

The other problem is that dpkg does not use tar on unpack, it uses its
own internal tar extractor so that it can handle directly the files
being unpacked, which will refuse any unknown tar file type.

In any case, yes dpkg should eventually support something like that,
but it would need to be outside of the filesystem, as in it would need
to be tracked in the dpkg files database, and possibly be applied on
the filesystem, because there's no guarantee the current filesystem
will have xattr support.

My idea is to add some kind of manifest file at build time, most
probably based on the new mtree(5) format. I think I migth have code
around parsing that, but I'd need to check. Let me get 1.17.14 out of
the way and I can come back to you with more concrete plans and code.

Thanks,
Guillem