<quote who="[EMAIL PROTECTED]"> > One that accepts the incoming tcp port 25, and then does the checks in > realtime.
Every modern MTA should do this, indeed, even decidedly unmodern MTAs do. ;) > ie: > EHLO; mail > <check with rbl lists if IP or reverse lookup is an open relay, if so, > send a 530 Access Denied and exit> > 250 myserver > MAIL FROM: <[EMAIL PROTECTED]> > <check system wide blacklist, if exists, then send 530 Access Denied and > exit> > 250 Ok > MAIL TO: <[EMAIL PROTECTED]> > <check user blacklist, if exists, then send a 550 recipient address > rejected> Lots of fun policy stuff for every step of the SMTP dialogue: http://www.postfix.org/uce.html > 250 Ok > DATA > Then compare the data line by line, and if it is considered spam status, > stop it at that line with a 530 Access Denied and Exit. This starts getting dangerous, particularly if you're using another piece of software to do the checking (highly likely). postfix has a content filtering system that hands off the email after accepting it, and you can also use the simpler regexp header_checks and body_checks (and limit the amount of body data checked, so you're not running regexps over every line of every email). - Jeff -- Come to gnome.conf.au 2004! http://www.gnome.org/~jdub/2004/gnome.conf.au/ "What inspired you to become a bus driver?" "Linus Torvalds." -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug