Setting Sendmail to Refuse Possibly Forged Headers

[Dan Nelson]

In the last episode (Apr 15), antenneX said:
> > SLocal_check_mail
> > R$* $: $1 $| $&s Put helo name in workspace
> > R$* $| $={RejectHelo} $#error $@ 5.7.1 $: "550 Spammer access denied"
> > R$* $| $* $: $1 Extract helo from workspace if it doesn't match
> > #-/\-
> 
> Dan: Your suggestions here were appealing, but I'm batting zero.
> 
> 1- Will milter-sender work alongside spamass-milter...??
>     I *think* it was working on a test box, but failed on production box.

They should coexist peacefully.  In general, milters should be unaware
of each other.  I'd put milter-sender in front of spamass-milter, since
spamassassin can be CPU-hungry and there's no need to mark a message as
spam if milter-sender is just going to deny it anyway.
 
> 2- Each of your 3 lines above for "local_check_mail" yelled about
> expecting a Tab when sendmail was restarted... not sure how to fix
> that.....

My outgoing message had tabs; if your mailer removes them or replaces
them with spaces, here's where they go:

R$*<TAB>$: $1 $| $&s<TAB>Put helo name in workspace
R$* $| $={RejectHelo}<TAB>$#error $@ 5.7.1 $: "550 Spammer access denied"
R$* $| $*<TAB>$: $1<TAB>Extract helo from workspace if it doesn't match

-- 
	Dan Nelson
	dnelson at allantgroup.com