RE: Unknown mechanisms

On Fri, 2 Sep 2011, Murray S. Kucherawy wrote:

>> New mechanisms (unlike new modifiers) can change the SPF result.  If we were to
>> add a new mechanism, then we'd have to bump the version.  If an unknown
>> mechanism is encountered, the correct result is permerror.
>
> Fair enough.
>
> I'd like that to be explicit.  As it is now an implementer could decide that
> ignoring unknown mechanisms is simplest (and a common practice, such as in
> DKIM and its friends), leaving the remaining record parsable and usable.
> Something like "An SPF-aware receiver encountering an unknown mechanism MUST
> return a 'permerror' result" would be good to add in the right place.

FWIW, the test suite will flunk an implementation that fails to give
permerror for the "moo" mechanism.

--
 	      Stuart D. Gathman <[email protected]>
     Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flammis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.