著者: Alan J. Flavell 日付: To: 'Exim User's Mailing List' 題目: Re: [Exim] AOL - SPF - and EXIM
On Thu, 17 Jun 2004, Avleen Vig wrote:
> Actually if we really want to get picky about it, it doesn't say when
> you can't reject because of the HELO/EHLO.
Except that if you reject the HELO/EHLO, then you shouldn't accept the
message, since an accepted HELO/EHLO is mandatory before mail can be
sent.
So anyone who reads 4.1.4 as commanding them to accept the message,
could not logically reject the HELO/EHLO.
> It just says that you can't. Period. So if it's inappropriate after
> the HELO, rejecting it after RCPT BECAUSE of HELO should be equally
> inappropriate.
However, if you interpret it in that way, then the one sure-fire way
to get spam, viruses and other malware through would seem to be to put
a syntactically-valid domain on the HELO that's guaranteed to not
resolve. Then, no RFC-abiding netizen has any choice in the matter:
RFC2821 commands them to accept the offending item, with no ifs or
buts...
I don't buy that!!! If that's what the RFC is saying, then the RFC is
simply broken at this point.
As I said before, I read it as saying you are not to reject the mail
on this cause alone. If you have some other cause for rejecting the
mail, then you can still do it.