Re: [gentoo-dev] GPG Infrastructure for Gentoo (Was Council Meeting)

[Dawid Węgliński]

On Monday 30 November 2009 22:18:21 Richard Freeman wrote:
> Antoni Grzymala wrote:
> > How about getting back to GLEP-57 [1]? Robin Hugh Johnson made an effort
> > a year ago to summarize the then-current state of things regarding tree
> > and package signing, however the matter seems to have lain idle and
> > untouched for more than a year since.
>
> One concern I have with the GLEP-57 is that it is a bit hazy on some of
> the implementation details, and the current implementation has some
> weaknesses.
>
> I go ahead and sign my commits.  However, when I do this I'm signing the
> WHOLE manifest.  So, if I stabilize foo-1.23-r5 on my arch, at best I've
> tested that one particular version of that package works fine for me.
> My signature applies to ALL versions of the package even though I
> haven't tested those.
>

I may be wrong - then please correct me. You don't sign every package versions 
but Manifest. Thus you somehow prove every file checksum is correct. If there 
were any changes made on server side, those checksums would be incorrect 
according to your signed Manifest. Currently any change may be fixed by whoever 
it is by the same command ebuild foo digest.

> Now, if we had an unbroken chain of custody then that wouldn't be a
> problem.  However, repoman commit doesn't enforce this and the manifest
> file doesn't really contain any indication of what packages are assured
> to what level of confidence.

That's what should be discussed - forcing developers to sign their commits and 
implementing this support in package managers.

>
> If we want to sign manifests then the only way I see it actually
> providing real security benefits is if either:
>
> 1.  The distro does this in the background in some way in a secure
> manner (ensuring it happens 100% of the time).
>
> 2.  Every developer signs everything 100% of the time (make it a QA
> check).
>
> The instant you have a break in the signature chain you can potentially
> have a modification.  If somebody cares enough to check signatures, then
> they're going to care that the signature means something.  Otherwise it
> only protects against accidental modifications, and the hashes already
> provide pretty good protection against this.
>

That's not really true. I see tips like "if you have digest incorrect, run 
ebuild foo.ebuild digest" very often. Really small group of people care about 
broken digests. :(

-- 
Cheers
Dawid Węgliński