ietf-openpgp
[Top] [All Lists]

Re: [openpgp] Non-SHA-1 fingerprints in signatures [was: Proposal for a separable ring signature scheme...]

2014-03-13 21:40:34
On Mar 13, 2014, at 9:28 PM, Vincent Yu <v(_at_)v-yu(_dot_)com> wrote:

On 03/13/2014 06:02 PM, Jon Callas wrote:
My suggestion is that you write up an I-D, and push it.

My quick read looks like this is a useful thing, and it would be nice to 
have. Just as Andrey pushed an ECC draft and there have been others, it'd be 
a great way to go.

As DKG noted, we have a constant collision, but that's not a big deal. 
That's why we have IANA.

     Jon

Thanks for your comments. I plan to write up and submit an I-D if no one 
points out egregious problems with the current proposal.

In past threads, there were discussions about supporting non-SHA-1 
fingerprints [1] and including full issuer fingerprints in signatures [2]. 
You forwarded to this list a proposal for a new fingerprint [3]. Did anything 
concrete come out of that proposal or other discussions?

In my proposal, I am using key IDs (i.e., the rightmost 8 octets of SHA-1 
fingerprints) in a new signature subpacket, but I would like to switch to 
non-SHA-1 fingerprints if there is a standard or consensus about how they 
should be formatted. This is an opportune time to introduce such fingerprints 
since backward compatibility is not a relevant consideration.

Changing fingerprints raises a lot of complexity that you may not want tied to 
your I-D.  I suspect that non-SHA-1 fingerprints will not happen without an 
accompanying V5 key format.

With regards to your I-D, I recommend using the full fingerprint instead of the 
64-bit key ID in your sig subpacket.  That is the least ambiguous way to 
specify a key today, and while it is V4 specific, it can be easily changed if 
and when the fingerprint changes, just like the revocation key subpacket will 
need to be.

(Though see https://www.ietf.org/mail-archive/web/openpgp/current/msg00260.html 
)

David

_______________________________________________
openpgp mailing list
openpgp(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/openpgp

<Prev in Thread] Current Thread [Next in Thread>