It seems to me that the wrapped original mail could be signed by the
forwarding list processor so that the DMARC recipient would accept the
forwarded mail as coming from the forwarder and the ultimate MUA would
be able to verify that the wrapped messaged was indeed wrapped by the
forwarding list processor and transparently unwrap the original
email.
Since some list mail is re-forwarded along the path to the ultimate MUA,
this mechanism should support multiple layers of signed wrapping.
Dave Morris
On Sat, 13 Sep 2014, Sabahattin Gucukoglu wrote:
On 12 Sep 2014, at 18:27, Dave Crocker <dhc(_at_)dcrocker(_dot_)net> wrote:
By definition, p=reject enforces a semantic that requires the owner of
the rfc5322.From domain to have a relatively tight relationship with the
operator sending the message.
IMO, it's quite reasonable to characterize this as conflating From: and
Sender:.
What tends to be missed, throughout all of the discussions about dealing
with the effect on intermediaries such as mailing lists, is that most or
all of the mechanisms being discussed for intermediaries will work
equally well for bad actors...
Indeed.
I wonder if it might not simply make more sense to warn users that the
information in the header fields cannot be trusted once they have been
remailed by an exploder of any kind. This way, transparent MUA
unwrapping of encapsulated list mail is a much more plausible solution
Cheers,
Sabahattin