Wed Jul 14 15:13:56 UTC 2010
> Date: Wed, 14 Jul 2010 13:29:38 +0200 > From: Jakob Hirsch <email@example.com> > > > "IPv6:" tag. That NANOG thread seems to say that exim generates > > > > Received: from s0.nanog.org (s0.nanog.org [2001:48a8:6880:95::20]) ... > > > > instead of > > > > Received: from s0.nanog.org (s0.nanog.org [IPv6:2001:48a8:6880:95::20]) ... > > > > Is that true? > > uhm... yes, that's true: > > Received: from calcite.rhyolite.com ([2001:4978:230::3]:30997) > by ymmv.de with esmtps (TLSv1:AES256-SHA:256) > (Exim 4.72) > > I (and obviously others) wasn't aware that should be a "IPv6:" prefix. > Which "SMTP standards" say that? i think it's something sendmail just did, and that others have emulated. (i hate it, and my own received:-header parsers strip out "ipv6:" if they see it, before trying to use whatever's left as coloned-hex or dotted-dec). > Parsing Received headers is always dodgy, because it was never intented > to be machine readable. that's what i thought too, but there is a grammar and they are indeed meant to be machine readable. > The Right Way[tm] to do this is to tell the MTA to add a header line > (X-Sender-IP or something). yes but using Received: is how most inbound procmail recipes work. i think that anyone who depends on "ipv6:" and doesn't just strip it out and throw it away, should have to cite RFC chapter and verse on the matter.
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