On Thu, 21 Nov 2002, EXIM Users wrote:
> We are looking at version 4 but reading the docs for that suggets it also
> does a whole string match. Looking at the code I guess it wouldn't be too
> difficult to hack. Has anyone else done this already?
If you really want to do this, there is perhaps no need to hack. In Exim
4, use helo_try_verify. In the ACL you can test whether verification
worked or not. If not, you can look at the value of $sender_helo_name
and apply whatever rules Exim permits. The dnsdb lookup would allow you
to look up MX records.
However, as Greg Woods says, this is misguided:
On Thu, 21 Nov 2002, Greg A. Woods wrote:
> Yup, because what those servers are doing is flat-out not allowed by any
> SMTP-related standard. The greeting name _MUST_ be the principal
> hostname for the client. The whole idea is to clearly and uniquely
> identify the client _host_, not it's sub-domain. This has been a
> fundamental absolute requirement of SMTP for only about 20 years now.
Absolutely!
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.