I posted in the middle of everything...
> -----Original Message-----
> [mailto:exim-users-admin@exim.org] On Behalf Of moseley@???
>
> [copying back to the Exim list]
>
> On Sun, Sep 14, 2003 at 05:26:05AM +1000, exim@??? wrote:
> > > Bill Moseley
> > > Sent: Saturday, 13 September 2003 11:47 PM
> > [clip]
> > > Debian has a default /etc/aliases file that includes things like
> > > "daemon" and "postmaster" and "news". I'm finding spammers are
> > > using those names plus my domain to forge spam
> > > -- so I get the bounces, and lots of them.
> > > I'll want to keep "postmaster", but the others I'd like
> to limit to
> > > internal/local use.
> >
> > Would it be too extreme for you to outright fail any addresses that
> > don't go to real accounts? I have to following (along with
> all other
> > accounts that aren't for real people) in my /etc/aliases file.
> >
> > Postmaster: elc
> > root: :fail: Unknown user
> > bin: :fail: Unknown user
> > daemon: :fail: Unknown user
> >
> > This means that any mail destined for any of those users
> gets rejected
> > at SMTP RCPT time by default. Not exactly what you were
> asking, but,
> > close enough?
>
> Isn't that the same a just removing those from /etc/aliases?
> They will fail since they don't get directed.
Nope. (Exim4) I just had to run a test on it to make sure, but my fears
have been confirmed. If you knock out of those aliases then exim tries
to dilver the mail as that user to their home directory - not good. You
have to either explicitly fil the addresses or re-direct them to an
account that normally accepts mail.
> My concern is that an alias might be in there because some
> *local* process sends email there.
Most daemons send email to root (which should be aliased to a normal
user account), and not themselves. Actually I'm having a hard time
thinking of any program that sends email to system accounts other than
root. Who would read it? By the sounds you were only getting spam
bounces on the addresses anyway.
One disadvantage of specifically failing system addresses is that those
processes have to have a special rule added to the exim configuration
file to avoid sender verification (cos it fails ;) ). I have never seen
that little problem before. Crud. Bah, nothing on my systems sends me
email anyway.
> Is there a way in Exim 3 to select/limit a router based on
> where the mail is coming from? I.e. allow locally generated
> mail and mail from localhost and my local LAN?
I'm an Exim 4 boy, so this is probably someone elses area. I think 4
allows local mails regardless by default so no problems there.. Was
there a reason for not updating?
Anyway, a quick peruse of the 3.3 spec and.. a wild guess would say look
in the director that manages the aliases, but I can't spot any of the
options needed at that stage to differentiate between a local and remote
source.
Yikes, I just tried to come up with something but I think I'll let
someone who knows exim 3 to do this one.
Ted.
