On Fri, 7 Nov 2003, Kelley Reynolds wrote:
> While working on a particular problem, I noticed in the documentation
> that local delivery routers (by default, but changeable) do not deal
> with multiple domain recipients in the same envelope.
I'm not sure what you mean here. Maybe I've not explained things right
in the documentation. The routers deal with each address individually,
that is, one at a time. It doesn't matter if they are in the same or
different domains. Exim can certainly handle a message that has multiple
recipients in different domains. Heck, it wouldn't be much of an MTA if
it couldn't.
> I wondered what would actually happen in the unlikely even that that
> occured,
I must be misunderstanding what you mean by "multple domain recipients
in the same envelope" because it is by no means unlikely (indeed, it is
very common) to encounter messages whose recipients are in different
domains. For example, the central mail servers here at Cambridge
University serve cam.ac.uk, cus.cam.ac.uk, and many other xxx.cam.ac.uk
domains. Incoming mail may well have several recipients in several of
those domains.
> and found out that any e-mails to additional domains in the same
> envelope simply disappear, even though they appear to be delivered to
> the sending MTA.
Evidence, please. Exim should never lose messages, unless you configure
it to throw them away.
> Even though the occurence of this happening in the wild
> approaches zero, I wrote a little acl to drop anybody attempting it
> since likely only faulty MTA's (spammers) would even attempt it. Here
> it is for anybody that cares (and maybe somebody has a better idea to
> accomplish the same thing)
>
> # Disallow multiple domains in the same envelope
> warn set acl_m9 = $acl_m8
> set acl_m8 = $domain
>
> drop condition = ${if eq{$acl_m9}{$acl_m8}{0}{1}}
> condition = ${if eq{$acl_m9}{}{0}{1}}
> message = This SMTP server does not accept multiple domains in the same envelope
I think this will block legitimate mail.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
Get the Exim 4 book: http://www.uit.co.uk/exim-book