Public SourceMage Discussion List

["Sergey A. Lipnevich" <sergey AT optimaltec.com>]

Quoting "Jeremy Blosser (emrys)" <jblosser-smgl AT firinn.org>:

> > I would agree with you if there were an example of that. Examples of
> > generating a collision in the hash don't count because they do not
> > produce a valid source.  Or, I should say, do not produce valid source
> > yet. Chances of this happening are much lower than producing a hash
> > collision.
>
> It's probably only a matter of time at this point til it happens
> publically, and keep in mind that history indicates that whatever the
> private sector is doing today was done by the NSA 10 years ago.
> Regardless, the sorcery team's position as I understand is that they want
> to switch sooner than later so they don't have to be hash experts.  Their
> talents are better used elsewhere.

Encryption is always a matter of time. But the events we're anticipating here
are a matter of a *very long* time. Longer than I would care.

> > You're signing the receipt, meaning you agree that you received the
> > package.  There's no analog that I can think of in terms of source code
> > tarballs.  Package has been accepted by the carrier, inspected for
> > controlled objects, and was wrapped. Package has a return address that
> > has likely been verified, and a trail of how it got to you. There's no
> > wrap or return address on tarballs, and nobody inspects them.  However,
> > see above about the analogy of signatures on documents. I think it suits
> > better.
>
> I wasn't trying to make a 1-to-1 analogy, I was only noting that signatures
> are used for different things, even in the real world.  A signature for a
> package means the person signing received the package.  A signature on an
> itemized invoice means that the person signing inspected the contents and
> verified what was there.  People can understand the difference, and this is
> not dissimilar to what we're talking about doing with GPG signing, even if
> it's not the exact same thing.

Please see my reply to Eric. In this analogy, I'd galdly sign the 
spell, but not
the tarball.

> Even GPG signing an email does not mean that I completely agree with the
> contents, or always will.  If you pull out this signed mail in 10 years it
> will not mean that you can make me say I agree with what it says (I may
> have changed my mind), but you can make me say I did write it on this date.

Again please see me reply to Eric. The contents of the email are 
irrelevant, the
signature doesn't mean that the content is true, it means *you* wrote 
it and you
vouch for it. As I said, if you wrote that you'd like to rob a bank and signed
it, your malicious intent is evident. If you wrote that all your money should
be transferred into someone else's account and signed it, you'll be left
without a penny whether you agree with it later or not.

> > In short, I object to *mandatory* GPG signatures, and I refuse to 
> > sign source
> > that's not mine with my name.
>
> Would you be willing to sign using a key that did not have your name, but
> had a UID:

Not really because it makes even less sense from the security point of view.
From the "integrity checking" POV, it's probably the same as a hash, 
but it's a
lot more difficult to manage and control.

> For the record, I originally felt as you did.  I changed my mind for two
> reasons (and one of them alone would have not done it):
>
> 1) I understand the sorcery team's position of wanting to offload this, and
> I agree with it.

If sorcery team wants to offload some work, that would be fine, but in 
this case
it would be offloading work *and* responsibility. I can't accept the
responsibility part of it.

> 2) I believe that we can explicitly tell users what our signatures mean and
> don't mean.  Stuffing it in the key UID is one form of this.

I don't think so. Try to remember when was the last time you read some package
maintainers' explanation of what their signature means or doesn't mean? I bet
you can't. The reason why is because there's a common meaning of a signature,
and digital signatures were created to extend this meaning to the digital
realm. You can resist it and try to redefine it, but I wouldn't imagine you
succeed in doing so.

What we're trying to do is done by hashes, not signatures, and I have 
yet to see
a reason to change that. A signature fortifies a hash, but puts more
responsibility on the signee. I don't say we have to abandon the 
signatures, on
the contrary, but I don't want to sign what's not mine. Why is that so hard to
understand?

Sergey.