On Fri, Nov 20, 2015 at 01:53:10PM +1100, Tim Connors wrote:
Isn't cascading Received: from .* (.*) by headers completely normal in mail?
Yes, it's completely normal in "plain message forwarding"...
Isn't a mailing list just another MTA? Can't it just prepend another Received: line and forward it on?
Well, they sort of are, and they could just...
If that breaks DMARC/SFP, doesn't that then mean DMARC/SFP is fundamentally broken?
...which may (depending on the SFP policy) cause the mail to eventually bounce, thus a mailing list will rewrite the Return-Path (e.g. with a VERP address) Co-incidentally, your mail didn't pass an SFP check, and your message may have been rejected if Google didn't publish a SOFTFAIL policy. However, given the existing controversy, and from the tone of your post, I'm sure you already know all that...