Re: Adding a pointer to a WebID in a GPG pubkey

Hi.

A bit more details on second thought...

Jonas Smedegaard <dr@jones.dk> writes:

> Quoting Olivier Berger (2013-08-27 17:13:50)
>> I've been discussing web of trust with Andrei and others, in the 
>> context of the Debian project, which already relies a lot on the 
>> GPG/OpenPGP web of trust.
>> 
>> So I've been wondering how to add a WebID pointer in a pubkey. 
>> However, there doesn't seem to be some easily manageable way to add 
>> RDF to a key (or at least I didn't discover it)... and I thought that 
>> a QR code as a photo ID in the pubkey could be something to test out.
> [details snipped]
>> Would this be an interesting step to promote WebID, by taking 
>> adventage of the existing GPG web of trust ?
>
> I find it a bad approach: the Photo is meant for visual identification, 
> not as storage container for whatever possible to serialize in a visual 
> container.
>

Yes, that makes sense, of course, but on the other hand, the specs (RFC 4880)
mention :

 5.12.1. The Image Attribute Subpacket

   The Image Attribute subpacket is used to encode an image, presumably
   (but not required to be) that of the key owner.

Also, you are not limited to one such single photo id.

So, I guess one may have for instance 2 photo ids, one being primary,
and being the real picture of the owner, and another, being the QR code
containing the RDF link to the WebID...

So, I have just modified my pubkey at [0] to add such a
scheme. Showphoto in GnuPG should thus behave as you'd expect.


Btw, in principle, there could be other kinds of "user attributes"
("5.12. User Attribute Packet) than the "image attribute" subpacket,
alhough the specs don't describe them.

   The User Attribute packet is made up of one or more attribute
   subpackets.  Each subpacket consists of a subpacket header and a
   body.  The header consists of:

     - the subpacket length (1, 2, or 5 octets)

     - the subpacket type (1 octet)

   and is followed by the subpacket specific data.

   The only currently defined subpacket type is 1, signifying an image.
   An implementation SHOULD ignore any subpacket of a type that it does
   not recognize.  Subpacket types 100 through 110 are reserved for
   private or experimental use.

So I guess it could in principle be possible to have a real RDF fragment
as such user attributes, that the pubkey could transport, which could be
self signed or cross signed by others, much like the current user ids or
photo ids.

Let's see if someone follows such paths some day...

Best regards,

[0] http://www-public.telecom-sudparis.eu/~berger_o/info/pubkey/pubkey.txt
-- 
Olivier BERGER 
http://www-public.telecom-sudparis.eu/~berger_o/ - OpenPGP-Id: 2048R/5819D7E8
Ingenieur Recherche - Dept INF
Institut Mines-Telecom, Telecom SudParis, Evry (France)

Received on Tuesday, 27 August 2013 20:36:39 UTC