[Mailman-Developers] Sendmail.cf wizard question - virtual-hosting

[Ken Manheimer]

I have a question for any sendmail.cf wizards out there - a hack to a
recent cf ruleset (mine is from 8.9.0) to circumvent what i consider a
bug, or at least a misfeature, that interferes with using sendmail for
"virtual hosting".

The problem was that no matter what i did (building the cf with
masquerading, virtual user, whatever it was), the "to:" header of
messages posted to a maillist was always transformed to the primary
address of the host where the maillist was situated, even when the
original message was addressed to one of the "virtual" host addrs.  I
eventually poked and prodded in the rulesets (shudder), and discovered
that commenting out one rule, which is supposed to use the name server
to canonicalize an address, prevents that transformation from
happening.  (It's part of ruleset 96, which was apparently is "the
bottom half of ruleset 3" - boy, i *do not like* touching cf ruleset
code!)

I've been running this change for a few weeks on my workstation and on
python.org, and it doesn't seem to be causing any problems.  Even
better (:-), it does seem to prevent the unwanted transformation of
the original "to:" addresses.  However, i don't _really_ know that my
change won't disrupt something that isn't exercised on my machines.
So i'm hoping that informed sendmail folk out there might be able to
do a sanity check on this change.  I'm including, below, an artifical
diff of the cf file before and after, to show the specific difference,
for a sendmail 8.9.0 cf file.  Please let me know what you think, if
you have some clear knowledge of this stuff!

Ken Manheimer		  klm@python.org	    703 620-8990 x268
	    (orporation for National Research |nitiatives

	# If you appreciate Python, consider joining the PSA! #
		  # <http://www.python.org/psa/>. #


*** sendmail.cf	1998/08/03 21:27:06	1.6
--- sendmail.cf	1998/08/03 21:27:17
***************
*** 516,522 ****
  R$* < @ $+ . . UUCP . > $*	$@ $1 < @ $2 . > $3
  
  # pass to name server to make hostname canonical
! R$* < @ $* $~P > $*		$: $1 < @ $[ $2 $3 $] > $4
  
  # local host aliases and pseudo-domains are always canonical
  R$* < @ $=w > $*		$: $1 < @ $2 . > $3
--- 516,524 ----
  R$* < @ $+ . . UUCP . > $*	$@ $1 < @ $2 . > $3
  
  # pass to name server to make hostname canonical
! # klm - looks like this converts to primary canonical, which transforms
! #       e.g. a virtual-hosted "to:" address when we don't want it to be...
! #R$* < @ $* $~P > $*		$: $1 < @ $[ $2 $3 $] > $4
  
  # local host aliases and pseudo-domains are always canonical
  R$* < @ $=w > $*		$: $1 < @ $2 . > $3