[Exim] IP address in Received headers

I still think this guy is nuts, but here is some argument he sent me on
the matter. It no longer really affects me, since I have turned of
log_incoming_port anyway, but I forward it for completeness.


---------- Forwarded message ----------
Date: Tue, 11 Sep 2001 14:09:59 -0400
From: Postmaster <postmaster@???>
Subject: Re: your mail server is screwing up headers

I disagree that RFC-822 does not address IP addresses in the
Received line.

Under 4.1 (Message Specification) "Syntax", is found the reference
to "domain" in the Received line:

      received    =  "Received"    ":"            ; one per relay
                        ["from" domain]           ; sending host
                        ["by"   domain]           ; receiving host
                        ["via"  atom]             ; physical path
                       *("with" atom)             ; link/mail protocol
                        ["id"   msg-id]           ; receiver msg id
                        ["for"  addr-spec]        ; initial form
                         ";"    date-time         ; time received

Under 6.1 (Address Specification) "Syntax" is found the definition of
domain and sub-domain:

      domain      =  sub-domain *("." sub-domain)
      sub-domain  =  domain-ref / domain-literal

Then under 6.2.3 "Domain Terms" is found the definition of
domain-literal:

         Domain-literals which refer to domains within the ARPA  Inter-
         net  specify  32-bit  Internet addresses, in four 8-bit fields
         noted in decimal, as described in Request for  Comments  #820,
         "Assigned Numbers."  For example:

                                  [10.0.3.19]

I checked RFC-2822, and though it says it "obsoletes" RFC-822,
it still refers to "domain-literal" and does not redefine it. If I missed
something, please refer me to the proper document.

I have been using the current spam filtering definitions and recipes
for over a year. Only once before have they blocked legitimate mail,
and that was when Prodigy put in new mail services a few months
ago. I notified them, just as I notified you, and within two days their
headers were once again acceptable to our filters. However, I don't
believe they changed it just for me.

I'm really surprised you haven't received reports of undeliverable mail
from other Postmasters. Why did this just start happening in the past
week? Previous to then, messages from your server passed our filters.

regards,        -carey  ( up.net tech support, postmaster, & other stuff )

At 11:11 AM 9/11/2001 -0400, you wrote:


>Actually, RFC-822 makes no specification as to the existence or format
>of any IP addresses in Received: headers. Neither does RFC-2822, which
>has superseded RFC-822.
>
>If you beleive it does, we would appreciate if you could refer to the
>specific section or paragraph therein which makes this requirement.
>
>
>On Mon, 10 Sep 2001, Postmaster mail filter wrote:
>
> > Hi,
> >
> > Messages from your domain are not being delivered because your mail server
> > is putting weird numbers in the Received line. RFC822 states that numbers
> > appearing in square-brackets must be valid IP addresses. Your server is
> > doing the following:
> >

[..]

An exim-generated Received: header, with an IP address and TCP port
number, eg [192.168.1.1.30987]

[..]

> >
> > The fifth group makes it an invalid IP address, and spam filters on the
> > Internet, including
> > ours, are trapping and trashing these messages. Please correct the form of
> > IP address
> > on the Received line so that your customers' e-mail gets delivered to the
> > intended recipients.
> >
> > Thank you.
> >

> >       -carey  ( up.net tech support, postmaster, & other stuff )

> >
> >
>
>--