On Wed, Jun 29, 2005 at 06:24:40PM -0400, Greg A. Woods said:
> [ On Wednesday, June 29, 2005 at 14:55:47 (-0700), Steve Lamb wrote: ]
> > Subject: Re: [exim] a large number of domains fronted by Exim are refusing bounces...
> > Which has been refuted, numerous times, by the
> > very valid point that to do so would make other things which should be easy
> > more difficult than they need to be.
>
> Well, such attempts at refutation have failed miserably since they've
> all failed to take into account that there are other in fact other
> existing and successfull implementations which do make it difficult for
> admins to blindly ignore such basic protocol requirements as handling
> messages which have null return paths.
>
> I've never heard anyone complaint that such implementations are more
> difficult to use than they need to be either.
>
> As y'all know I'm most familiar with Smail, which makes it very hard for
> the average admin to unilaterally block messages with an empty sender
> address, so for another example let's see if you can read between the
> lines of this answer from the Postfix FAQ:
>
> 59. I get a lot of spam with a blank envelope sender address. How can
> I block these?
>
> You don't want to block messages based on the fact that they have a
> null return path.
[...]
> Or maybe this from the Sendmail on-line docs:
>
> How do I reject "MAIL FROM:<>"?
>
> Don't do it! Internet standards require to accept e-mail with an
> empty sender address, i.e.,
[...]
You'll note that neither of these say, "you can't do it", they say
"don't do it". In sendmail at least it would be fairly easy to write
an access rule or a milter to block all mail from a null sender. I would be
extremely surprised if postfix couldn't also do similar things, as it has
access maps of a sort. If, in fact, postfix is hobbled in this way,
then that's another reason I don't use it.
--
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| Stephen Gran | One Bell System - it used to work |
| steve@??? | before they installed the Dimension! |
| http://www.lobefin.net/~steve | |
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