Mr Zesty's Brain Dump: Qmail Wildcard Aliases

Qmail Wildcard Aliases

I had a client ask for a number of email accounts @clientdomain.com and for any email addresses that didn't match to go into a default mailbox sales@clientdomain.com

I soon realized that qmail was not capable of doing this. By using a ~alias/.qmail-default file I could deliver ALL "leftover" email to a specific mailbox - but there wasn't a way to deliver it only on a per-domain basis.

qmail only supports using locals or virtualdomains, but not a combination of both - which I would need. (The alternative was to set up ~alias/.qmail-clientdomain-user aliases for each user - and have to manage that mess too, delivering mail to mailboxes at another domain... ugly).

Instead I use the ~alias/.qmail-default file to send all non-matching email to procmail, where I filter out email for a specific domain to be forwarded - and set the rest of the mail to bounce back to the sender with a genuine qmail failure message.

Create your procmail recipe file. I named this file ~alias/wildcard.procmailrc

PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin
LOGFILE=/tmp/wildcard.procmaillog
SHELL=/bin/sh

# If a message has reached this far - qmail does not recognize the recipient, it's up
# to us to handle the message ourselves.

# qmail takes the value of the smtp 'rcpt to:' field and provides it in the message
# headers as the Delivered-To: field.  I use that to figure out who the intended
# recipient of the message is.

:0
*	^Delivered-To.*@clientdomain.com
	! sales@clientdomain.com
 
:0
{
	# EXITCODE returns the status code (100) to qmail, which qmail interprets as a
	# fatal error and bounces the message for us!
	EXITCODE=100
 
	# procmail is still holding onto a copy of the message - and will deliver it to
	# /var/spool/mail/alias unless we tell it to drop it.
	:0
	/dev/null
}

Next set up the ~alias/.qmail-default file that handles all uncrecognized recipients
| /var/qmail/bin/preline /usr/bin/procmail -m wildcard.procmailrc