Re: Signer's User ID

David Shaw <dshaw@jabberwocky.com> Thu, 21 July 2005 12:04 UTC

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Date: Thu, 21 Jul 2005 07:47:43 -0400
From: David Shaw <dshaw@jabberwocky.com>
To: ietf-openpgp@imc.org
Subject: Re: Signer's User ID
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On Thu, Jul 21, 2005 at 07:39:32AM +0200, Werner Koch wrote:
> 
> Hello!
> 
> I'd like to have a clarification of the signature subpacket
> 
>   5.2.3.22. Signer's User ID
> 
>     (String)
> 
>     This subpacket allows a keyholder to state which User ID is
>     responsible for the signing. Many keyholders use a single key for
>     different purposes, such as business communications as well as
>     personal communications. This subpacket allows such a keyholder to
>     state which of their roles is making a signature.
> 
>     This subpacket is not appropriate to use to refer to a User
>     Attribute packet.
> 
> It is not clear to me whether the string should be a verbatim copy of
> the content of a User ID packet or some other information.  The second
> paragraph could be viewed as a hint for a verbatim copy.

I suggested that second paragraph when I was documenting the user
attribute / photo ID stuff.  There are some problems using a Signer's
User ID with attribute IDs, both in size and in knowing how to parse
the thing.

A while back, I posted a proposal to fix this:

  http://www.imc.org/ietf-openpgp/mail-archive/msg04775.html

David