Re: [exim] a large number of domains fronted by Exim are ref…

Top Page
Delete this message
Reply to this message
Author: Exim User's Mailing List
Date:  
To: Stephen Gran
CC: Exim User's Mailing List
Subject: Re: [exim] a large number of domains fronted by Exim are refusing bounces...
[ On Wednesday, June 29, 2005 at 23:42:30 (-0400), Stephen Gran wrote: ]
> Subject: Re: [exim] a large number of domains fronted by Exim are refusing bounces...
>
> You'll note that neither of these say, "you can't do it", they say
> "don't do it".


Of course -- the authors of the FAQ entries I quoted are not stupid and
the probably don't want to be called stupid for saying something that's
clearly false.

However you also won't find any hints from them as to how to do it
either.

In Smail it's simply not possible to block empty sender addresses in any
general fashion since the empty sender address is handled inside the
code and is never passed for checking to any sender address controls,
and also because the sender address is checked only using controls that
apply at MAIL time (i.e. the sender address is checked once and if it is
accepted the 250 reply is returned, otherwise a 450 or 550 reply is
returned and the transaction cannot proceed) and there are no provisions
for using the sender address in later controls that apply to RCPT, DATA
or end-of-DATA commands. Smail is of course designed to be easy to
configure and difficult to configure incorrectly, and it is also
designed to be simple to use, i.e. any SMTP errors can only occur at the
point in the transaction where they apply. Exim is designed to be
extremely flexible without concern for many protocol constraints and
thus suffers from being easy to configure incorrectly, and Exim also
suffers from being extremely obtuse and hard to use on the SMTP side.

-- 
                        Greg A. Woods


H:+1 416 218-0098  W:+1 416 489-5852 x122  VE3TCP  RoboHack <woods@???>
Planix, Inc. <woods@???>          Secrets of the Weird <woods@???>