Re: [Exim] Rumplestiltskin attacks anyway to combat them?

Hi lists, on Wed, 23 Jun 2004 19:32:28 -0500 you wrote:

Please don't top post. Thanks.

[Exim public front end to a backend mail system]
> > Either teach your MX what the valid user list is, or enable callouts
> > on your verify_recipient so it can ask the internal box.
> OK I can't teach it since we have way way to many changes internally
> unless I setup nfs or rsync (not going to happen EVER!!!)

You could use LDAP? Then it will be synchronised immediately. Or build a
list every hour (or 30 minutes, or 10 minutes, or whatever...) from
whatever user database you have and scp/rsync it across. I don't see the
big deal in copying 1 file across every now and then.

> I do like the other idea. I would like it to verify the name then
> deliver the email to the internal server. I am not sure as of this
> minute how to do this but I do have a nice think exim 4.3x manual
> sitting here next to me so I guess it's RTFM this weekend on callouts.

It won't take much RTFMing ;)

Just change:

verify=recipient

to

verify=recipient/callout=20s

It's as simple as that. (There are various options you can add to the
callout; see the manual - but that will get you up and running).

Of course, this works assuming that the internal server rejects bad
recipients at SMTP time. If it's a Microsh*t Sexchange server by any
chance, it won't unless you're using the 2003 edition and specifically
enable it. But if you're using that heap of junk, then you may be able to
just get your frontend Exim machine to do an LDAP lookup against your user
list on the MS network.


Tim