[ietf-dkim] SSP vs. reputation (was: ISSUE 1521 -- Limit the application of SSP to unsigned messages)

[Charles Lindsey]

On Fri, 25 Jan 2008 09:36:49 -0000, Frank Ellermann  
<nobody at xyzzy.claranet.de> wrote:

> Hector Santos wrote:

> On my dead box I have a few old mails From: you.  Under mail
> rules since RFC 822 I am entitled to resend them to say Eric,
> maybe in a discussion about the merits of SMTP HEAD vs. SREJ.
>
> That you (as domain owner) can suddenly try to decree that I
> cannot resend your old unsigned mail to Eric is preposterous
> and a design issue in SSP.

Actually, it is a design issue in DKIM. If Hector wants to prevent you  
resending his messages to Eric, all he has to do is to include the  
relevant "Resent-*" headers within the scope off his signature (which  
amounts to a declaration that there are none). So if you then resend them  
to Eric, Eric will find that Hector's signature no longer works (and, of  
course, Hector's SSP=strict :-( ).

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
Tel: +44 161 436 6131                       
   Web: http://www.cs.man.ac.uk/~chl
Email: chl at clerew.man.ac.uk      Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K.
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