[Mimedefang] What about DKIM

kd6lvw at yahoo.com kd6lvw at yahoo.com
Wed May 8 17:06:00 EDT 2013


--- On Wed, 5/8/13, Philip Prindeville <philipp_subx at redfish-solutions.com> wrote:
> On Apr 1, 2013, at 4:22 PM, Jan-Pieter Cornet <johnpc at xs4all.nl> wrote:
> > Hey, I like DMARC. I've even implemented DMARC
> verification in MIMEDefang ;) (the reporting bit is a
> stand-alone process).
> 
> Any chance of posting your changes? I'd like to try implementing it outbound…

Exactly what is the point behind DMARC?

DKIM already has feedback elements in its declarations.

SPF doesn't explicitly have such, but generally the difference between "FAIL" and "SOFTFAIL" implies such (the latter as an indication of a DSN request as opposed to SMTP rejection, as well as macro expansion for the "exists" operator in combination with DNSBL DNS-request logging as suggested in RFC 4408, Section 9).

"Therefore, why reinvent the wheel?"

I would be hesitant of any scheme that claims that its predecessors were "developed over a decade ago" when it is unaware of their histories. SPF didn't come about until 2004 (9 years ago; not published formally as an RFC until 7 years ago), and DKIM was created in 2004 (9 years ago; RFC published in 2007 - 6 years ago).
[References from the http://www.dmarc.org/overview.html web page.]

Additionally, I would also be hesitant to adopt any scheme backed by an organization (Google / Gmail) who can't even provide the simplist of RFC/Standards compliance for their own mail.  Standard 10 (RFC 821) requires that "Received:" headers which claim SMTP compliance (i.e. have a "with SMTP" clause) MUST also have a "from" clause, which Gmail omits; a standards violation.  They have been made aware of this in their feedback forums and have refused to fix it.



More information about the MIMEDefang mailing list