On 2021-11-11 at 14:53:01 UTC-0500 (Thu, 11 Nov 2021 20:53:01 +0100)
Togan Muftuoglu <tog...@dinamizm.com>
is rumored to have said:
"Matus" == Matus UHLAR <- fantomas <uh...@fantomas.sk>> writes:
Matus> you can check hostnames by using pcre map in
Matus> check_reverse_client_hostname_access. e.g. refuse regex
Matus> /(\d+)[.-](\d+)[.-](\d+)[.-](\d+)./ REJECT "generic DNS
refused"
Matus> (trailing . should avoid matching IP Addresses)
I tried it with the as
smtpd_client_restrictions = .... usual stuff
check_client_access pcre:
/etc/postfix/check_reverse_client_hostname_access.pcre
Unfortunately the regex matches legitimate senders as well.
As such a check always will. Legitimate senders, particularly large
ones, frequently use generic names. Simplistic patterns will match hosts
sending wanted mail.
I had INFO instead
of REJECT and that save the situation and the mails arrived.
Have I placed the check in the wrong place or am I back to square one.
Seems fine to me. Assuming you did not make an error in
/etc/postfix/check_reverse_client_hostname_access.pcre,
check_client_access in smtpd_client_restrictions would be the first
place you can do the check. If you put it in a later restriction list
you can use
2021-11-11T19:10:01.014343+01:00 myserver postfix/smtpd[3837]:
Anonymous TLS
connection established from mx1.goodserver.org[172.31.12.175]: TLSv1.3
with
cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519
server-signature ECDSA (P-256) server-digest SHA256
2021-11-11T19:10:01.062736+01:00 myserver postfix/smtpd[3837]:
NOQUEUE: info:
RCPT from mx1.goodserver.org[172.31.12.175]: "generic RDNS";
from=<SRS0=Dzai=P6=lists.goodserver.org=meetings-boun...@goodserver.org>
to=<john....@example.com> proto=ESMTP helo=<mx1.goodserver.org>
The munging of all the IPs and hostnames in those log lines makes them
entirely pointless. For all we know from that, the pattern match was
correct.
--
Bill Cole
b...@scconsult.com or billc...@apache.org
(AKA @grumpybozo and many *@billmail.scconsult.com addresses)
Not Currently Available For Hire
