ietf-dkim
[Top] [All Lists]

Re: [ietf-dkim] DKIM on envelope level

2009-10-30 06:57:16

On 29 Oct 2009, at 16:11, Dave CROCKER wrote:

First blank line after DATA.

Whether that affords sufficient value-add is an open question to me  
and probably others.

d/


There's no opportunity to do anything other than drop the connection  
there, is there? Not without modifying the SMTP spec. The only benefit  
is that you don't have to read the body into memory, but bodies are  
limited in size, so I can't think of much advantage.

A DKIM sig that only signed message headers would have a better chance  
of surviving mailing lists redistribution. It'd be available for re- 
use though, wouldn't it?

Ian Eiloart wrote:
--On 29 October 2009 09:45:31 -0400 Dave CROCKER 
<dhc(_at_)dcrocker(_dot_)net>  
wrote:


Rolf E. Sonneveld wrote:
... if they can do so, you accept the entire email.

In either case you accept the entire email,

Not necessarily. ....
....
I was just at a session at an industry trade association where the
question of  doing DKIM during SMTP came up.  There were  
operations folk
who very much liked  the idea of being able to obtain some DKIM  
benefit
during the SMTP session,  before the dot...

No one suggested modifying SMTP or DKIM specifications.

What /was/ discussed was the possibility of doing a signature that  
would
validate before DATA.  This merely requires a signature that does  
not
cover the  body.

I can't say that anyone sounded hugely enthusiastic about this,  
but given
that  there was interest in SMTP-time benefit, I think they just  
needed
to think about  this more.
Having two signatures, with one covering the body and relevant  
parts of
the  message header, and the other only covering the header,  
strike me as
a plausible  use of DKIM, worth considering.  I've no idea whether  
it
would provide any or  enough value-add.  However it is only a  
stylized
use of the existing standard,  and so the cost of experimenting  
with it
is reasonable.
So, how do you get the headers without the body?

d/

-- 

 Dave Crocker
 Brandenburg InternetWorking
 bbiw.net

-- 
Ian Eiloart



_______________________________________________
NOTE WELL: This list operates according to 
http://mipassoc.org/dkim/ietf-list-rules.html