On Tue, 8 Oct 2002, Alan J. Flavell wrote:
> Recalling this snippet from v3 spec.txt chapter 45 :
> In an attempt to shut such MTAs up, if the same host sends the same bad sender
> for a third time within 24 hours, MAIL is accepted, but all subsequent RCPT
> commands are rejected with a 550 error code. This means 'unknown user' and if
> a remote mailer doesn't treat that as a hard error, it is very seriously
> broken.
All that rather baroque stuff was removed in Exim 4 on the grounds that
testing for bad senders can now be done at RCPT time.
> We encountered just this problem recently - but with exim v4. As it
> happens, the sender attempted to reach us with the traditional
> mass-mail "bad header",
>
> To: <Undisclosed-Recipient:;>
>
> and we attempted to reject it on syntax. But I guess this would be
> the same for any kind of rejection at end of data?
Yes. And bad syntax rejection would have been the same in Exim 3. You
can't test the headers until after DATA.
> Any thoughts of a solution that works in v4, following the kind of
> strategy as described for v3 above?
I'm afraid you are chasing a red herring here. That V3 strategy worked
only for sender checking, not for checking anything after DATA.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
