Henrik K a écrit : > On Wed, Oct 22, 2008 at 03:47:53PM +0200, Matthias Haegele wrote: >> I think this is rather a bad idea. I would prefer to treat them on their >> behaviour >> (use helo checks, check for reverse dns ..., you should find several >> examples in this thread, from mouss ...) . >> What would prevent a spammer to name his box "smtp" e.g.? > > Please think more. > > Preventing GREYLISTING with such whitelist is fine. Such servers retry. > It also benefits to check it before FP-prone regexps like what was posted > before. You can use dnswl for same purpose. > > Spammers can't fake reverse DNS. If they have a "legimate" server of their > own, it will be blacklisted soon enough anyway. > >> You could use the botnet plugin for Spamassassin if used at your site. > > Botnet is blah, it doesn't even check domain boundaries and as such might > have FPs on multi-tld.
It FPs on verizon relays. sigh. > Not to mention the other FPs it can have, especially > with default configuration. It offers no benefits as you can (and should) > block all such dynamic hosts directly in your MTA. > yes, but some people may still want to check mail that was relayed by a (trusted) forwarder or fetched (fetchmail, getmail, ...). but I agree, I don't find the botnet plugin attractive.
