On Friday 14 December 2001 06:53, David Stults wrote:
> That is a possible solution, though I don't know how managable it would be
> on the scale I would have to implement it on.  Not that we have a lot of
> turn-over, per se, but as an ISP our customer base is in a constant state
> of flux.  After a few months, badrcptto would be pretty big :-).  Seems to
> me that the single biggest risk of putting this functionality into qmail
> would be the potential discovery of all valid mail addresses of our
> customers. That would be unfortunate.  There might be a way to mitigate
> that risk somewhat, and that is one thing I need to look at before pursuing
> this issue any further.  I pride myself on the security of all my systems,
> but I also pride myself on being able to offer a good set of services to
> our customers. It's a difficult balance sometimes.
>
> Dave

The valid email address discover is the biggest problem of this feature and I 
don't think that this problem has an easy solution.
If you drop after some erroneous rcpt to: can appen that some mta (like exim) 
that make a single smtp connection for multiple recipient of the same domain 
will get bounces after the max retry count.
In which way can you solve this problem ?
You have to consider the fact that this feature can become an _easy_ dos for 
your smtp and ldap servers.

felipe.

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