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Lines 1708-1709: <oops>
There is one deprecated macro letter: "h". It is expanded as the
string "deprecated".
That's a consequence of check_host() and its three arguments, the
HELO domain is unknown within check_host(). </oops>
Yes, I'm not so sure what to do about this. Macro letters came and
went over time. "h" is a big bear to put in as it is the only thing
that needs the HELO domain once processing is underway. It isn't
clear, also, how this macro can ever be useful, as there is just
nothing one can trust about the HELO domain.
It occurs to me that this could be useful in logging with exists in
tracking down misconfigured machines. If a Windows machine is sending
its NetBIOS name for HELO, or an MTA is not using a FQDN but just a
hostname, it might give some clue. You'd have to wade through all the
other misconfigured HELO domains and random HELO strings in your logs,
but it would be doable, perhaps with a combo of HELO and client IP in
exists. Most likely, most of the problem HELO domains are not going to
be on your local network (at least not initially until the there's wider
deployment). Although, after wider SPF deployment, problem HELO domains
would hopefully be rarer.
Andy Bakun