Date: Sun, 6 Apr 2003 09:27:35 -0700 From: Sereciya Kurdistani <sereciya@kurdistan.ath.cx> To: freebsd-ipfw@freebsd.org Subject: Re: Quick IPFW Question Concerning Sendmail Message-ID: <20030406162735.GA2797@kurdistan.ath.cx> In-Reply-To: <wui77g76.fsf@ID-23066.news.dfncis.de> References: <20030403182847.GC23675@kurdistan.ath.cx> <20030403135048.D92663-100000@diana.northnetworks.ca> <20030405174853.GA94738@kurdistan.ath.cx> <wui77g76.fsf@ID-23066.news.dfncis.de>
next in thread | previous in thread | raw e-mail | index | archive | help
Clemens, Thank you for taking the time to respond to my posting ;) Your comments are greatly appreciated. On Sun, Apr 06, 2003 at 06:18:05PM +0200, clemens fischer wrote: > Sereciya Kurdistani <sereciya@kurdistan.ath.cx>: > > > vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv > > ipfw add NNNN check-state > > ipfw add NNNN allow { udp or tcp } from any to any dst-port smtp,auth,smtps out via tun0 keep-state > > ipfw add NNNN allow log tcp from any to any dst-port smtp,smtps in via tun0 > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > > > This way, you don't have to allow any ports open for any incoming traffic not matched > > by the stateful rules, ;) > > are you sure this does what you want? i don't see the customary > anti-spoofing rules and there's a lot to be said for keeping state > especially on _incoming_ connections. if these are all your rules, > then what about incoming SMTP and AUTH on port 113? I think this is what I want... Would you please show me an example of anti-spoofing rules? I'd greatly appreciate it ;) ...Actually, I do have some facility for anti-spoofing rules, here they are: ipfw add NNNN skipto NEXT_BLOCK all from ${myhost} to not ${myhost} out via ${oif_1} ipfw add NNNN skipto NEXT_BLOCK all from not ${myhost} to ${myhost} in via ${oif_1} Do you mean I should check/filter for the private IP Addresses also? I'm not opening incoming AUTH because it seems unnecessary ; everything is running fine without opening that port. Incoming SMTP is handled with a rule like: ipfw add NNNN pipe N log tcp from any to any smtp,smtps in via ${oif} > i imagine your rules allowing _you_ to query others for AUTH data, > but you don't allow others this privilege. That's correct. Am I breaking a netiquette rule that I may not be familiar with? Thank you for your participation ;) -- +--------------------------------------------------------------+ | Welat xwe ava nake, dest bidin hevdu, pist nedin tu dijminî | | Riya azadiyê ne hêsan e, hêviya xwe bernedin, dema me | | nêzîk e. | | | | Hevaltî bi kesên du rû nekin, hevaltî bi hevdu ra bikin | | Ne ji hevaltiya wan kesên pêxwas û rû dirêj, ne bi wan | | kesên xwînperest, ne jî ji yên din. | | | | -Sêrêciya Kurdistanî | +--------------------------------------------------------------+
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20030406162735.GA2797>