On 2008-09-01 at 19:44 +0200, Alexander Stintzing wrote:
> I set up an exim with virtual users stored in a MySQL-Database. When I
> send a message to existentuser@??? it is scanned and delivered
> correctly. But when I send a message to nonexistent@??? which
> should be rejected immediately, it will be accepted at first, then it's
> spam-scanned and after that, Mail delivery failed: returning message to
> sender.
>
> Perhaps somebody will find the error:
The spam routers accept all mail, so all addresses will verify.
The entry in the ACL used for acl_smtp_rcpt which includes "verify =
recipient" will not use the Routers marked no_verify for determining
whether or not an address exists. However, if you do this then you'll
accept spam and generate a bounce, producing backscatter.
In simple configurations, you can get away with reproducing the
recipient verification checks on the spam Router which accepts mail, so
that it only accepts mail for those who would have been accepted anyway.
This might be awkward with your setup.
Which is why spam-scanning is really best not done by Routers, but in
the ACL logic. You're using spamc to use spam-assassin as a client; you
should look at setting spamd_address instead and then the 'spam'
condition in an ACL.
Read
http://wiki.exim.org/ExiscanExamples to get some ideas of what you
could be doing.
-Phil
