[Mimedefang] rDNS weirdness in MdF

[Philip Prindeville]

I'm seeing the following in my logs:

Nov 19 11:49:39 mail mimedefang.pl[11501]: no rDNS: reject [207.220.83.13]
Nov 19 11:49:39 mail mimedefang.pl[11501]: filter_relay tempfailed host 207.220.83.13 ([207.220.83.13])
Nov 19 11:49:39 mail sendmail[15385]: kAJInd3l015385: Milter: connect: host=host13.mainsequence.net, addr=207.220.83.13, temp failing commands


which I don't understand.  This means that:

sub filter_relay($$) {
    my ($hostip, $hostname) = @_;
...
    # we have to tempfail, since we might not be able to rDNS
    # because of transient non-authoritative server failures.
    # we could get more sophisticated and look at the exact failure
    # reason... this might offer a clue as to whether we can REJECT
    # or simply TEMPFAIL.  we TEMPFAIL because of a bug in Bind
    # involving TTL's less than 600 seconds.
    if ($hostname eq "[$hostip]") {
        md_syslog('info', "no rDNS: reject [$hostip]");
        return ('TEMPFAIL', "No rDNS records found");
    }
...

got triggered in my mimedefang-filter code.

So, the obvious question is, why is Sendmail able to resolve the
IP address but MdF can't?

I've set up my sendmail.cf as:

# name resolver options
O ResolverOptions=+AAONLY -DNSRCH -DEFNAMES


but this shouldn't be making a difference (since these affect
name-to-address lookups only).

(And is there direct access to h_errno?  It would be nice if
the functions that call gethostby*() exported the value of $?
in a global variable like $h_errno...)

What am I missing here?

Thanks,

-Philip