Miha Vrhovnik put forth on 10/21/2010 3:01 PM:
"Stan Hoeppner" stan@hardwarefreak.com wrote on 21.10.2010 10:29:50:
This will kill a huge amount of bot spam without dnsbl queries or greylisting, both of which can be resource hogs and add serious latency:
Stan, nice one. I'm wondering from where did you compile this one?
It was donated to me, and by default the community, by an anonymous poster to the spam-l mailing list, quite some time ago. We were having a discussion about blocking dynamic/generic rDNS hosts. Many of us were using really coarse regexes that others felt would catch alot of ham sources instead of just broadband/dynamic bots.
So, this generous gentleman donated his rDNS regex file. He was subbed with a gmail alias so there's no way to identify him (as I'm sure he prefers). Given the fully qualified nature and quality of the regexes and the fact there's over 1600 of them, and due to some of his posts, it leads me to believe he works for a major ISP/telco/etc in the US. Regardless of who he is, I'm really glad he donated this. It sure has given many a regex handicapped mail OP some seriously good additional a/s capability and saved many folk much time who are/were trying to build something similar from scratch.
Originally it was distributed as a Postfix regexp file. I ran it through PCRE and found a bunch of errors. I corrected those so it now runs as a PCRE without errors and with the added speed benefit of Postfix' PCRE engine.
Thanks again to the anonymous OP who shared this with us. :)
-- Stan