Hi, > BUT, I suspect there are a LOT of possible IPs that google will use to pop > mail > > from us ... > > You are right about that. According to my pop logs, my servers have > encounter about 1000 different IPs from google (920 actually). > Domain names are always like mail-[a-z][a-z][0-9]-[a-z][0-9][0-9]*. > google.com > By the way, I'm in europe, I'm not sure USA, Australia or Japan would see > the same gmail POP clients. >
You can make active checks for incoming connections. If reverse DNS record is valid (ip -> resolves to name -> resolves to same ip) and it matches '.* google.com$' regexp, then it is Google. -- Олег Петрачев _______________________________________________ freebsd-security@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-security To unsubscribe, send any mail to "freebsd-security-unsubscr...@freebsd.org"
