On Thu, Nov 11, 2021 at 08:53:01PM +0100, Togan Muftuoglu wrote:
> Matus> /(\d+)[.-](\d+)[.-](\d+)[.-](\d+)./ REJECT "generic DNS refused"
>
> Matus> (trailing . should avoid matching IP Addresses)
That "." would need to be a "[.]" (or "\."), otherwise it'll match the
last digit, of a 2 or 3 decimal digit IP octet. But I think that Matus
intended to also allow other non-digit charaters, therefore the correct
regular expression is:
/(\d+)[.-](\d+)[.-](\d+)[.-](\d+)\D/ REJECT "generic DNS refused"
Broken:
$ postmap -q "172.31.12.175" pcre:<(
printf '%s\n/^/ DUNNO\n' '/(\d+)[.-](\d+)[.-](\d+)[.-](\d+)./ REJECT
"generic DNS refused"'
)
REJECT "generic DNS refused"
Working:
$ postmap -q "172.31.12.175" pcre:<(
printf '%s\n/^/ DUNNO\n' '/(\d+)[.-](\d+)[.-](\d+)[.-](\d+)\D/ REJECT
"generic DNS refused"'
)
DUNNO
I must some day stop being surprised about all the sloppy regular
expressions I run into. Regular expressions are programs for a suitable
automaton, pay attention to detail!
--
Viktor.
