From owner-freebsd-net@freebsd.org Fri Jan 29 18:46:10 2021 Return-Path: Delivered-To: freebsd-net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id AFFCF4F59DE for ; Fri, 29 Jan 2021 18:46:10 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from hz.grosbein.net (hz.grosbein.net [IPv6:2a01:4f8:c2c:26d8::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "hz.grosbein.net", Issuer "hz.grosbein.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4DS5rx65WYz3mHy for ; Fri, 29 Jan 2021 18:46:09 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from eg.sd.rdtc.ru (eg.sd.rdtc.ru [IPv6:2a03:3100:c:13:0:0:0:5]) by hz.grosbein.net (8.15.2/8.15.2) with ESMTPS id 10TIjw5E061308 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 29 Jan 2021 18:45:59 GMT (envelope-from eugen@grosbein.net) X-Envelope-From: eugen@grosbein.net X-Envelope-To: vegeta@tuxpowered.net Received: from [10.58.0.10] (dadvw [10.58.0.10]) by eg.sd.rdtc.ru (8.16.1/8.16.1) with ESMTPS id 10TIjnfP081207 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Sat, 30 Jan 2021 01:45:49 +0700 (+07) (envelope-from eugen@grosbein.net) Subject: Re: How to not send traffic to TCP/IP stack To: Kajetan Staszkiewicz , freebsd-net@FreeBSD.org References: From: Eugene Grosbein Message-ID: <14fc5e0a-7d36-e040-f87c-48cf54490b7b@grosbein.net> Date: Sat, 30 Jan 2021 01:45:39 +0700 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=0.3 required=5.0 tests=BAYES_00,LOCAL_FROM, NICE_REPLY_A,SPF_HELO_NONE,T_SPF_PERMERROR autolearn=no autolearn_force=no version=3.4.2 X-Spam-Report: * -2.3 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * 0.0 T_SPF_PERMERROR SPF: test of record failed (permerror) * 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record * 2.6 LOCAL_FROM From my domains * -0.0 NICE_REPLY_A Looks like a legit reply (A) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on hz.grosbein.net X-Rspamd-Queue-Id: 4DS5rx65WYz3mHy X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=fail (mx1.freebsd.org: domain of eugen@grosbein.net does not designate 2a01:4f8:c2c:26d8::2 as permitted sender) smtp.mailfrom=eugen@grosbein.net X-Spamd-Result: default: False [0.09 / 15.00]; MID_RHS_MATCH_FROM(0.00)[]; R_SPF_FAIL(1.00)[-all]; FREEFALL_USER(0.00)[eugen]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; ARC_NA(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[grosbein.net]; RBL_DBL_DONT_QUERY_IPS(0.00)[2a01:4f8:c2c:26d8::2:from]; NEURAL_SPAM_MEDIUM(1.00)[1.000]; SPAMHAUS_ZRD(0.00)[2a01:4f8:c2c:26d8::2:from:127.0.2.255]; RCVD_COUNT_THREE(0.00)[3]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_HAM_SHORT(-0.81)[-0.810]; RCPT_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:24940, ipnet:2a01:4f8::/29, country:DE]; RCVD_TLS_ALL(0.00)[]; MAILMAN_DEST(0.00)[freebsd-net] X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 29 Jan 2021 18:46:10 -0000 29.01.2021 22:15, Kajetan Staszkiewicz wrote: > So far so good. But what if a LB wants to access the service? > > SYN: > 1. LB sends out a packet through public interface becuase that's where > the default gateway points. > 2. Core router sends the packet to one of LBs, in this case the same one > who originated the packet. > 3. It arrives at the public interface of LB where it is matched against > a route-to pf rule. A public-side pf state is created, a tag is assigned. > 4. pf's rout-to routes it to a LB Node / target. > 5. Leaves the LB over internal interface, matches the tag, another state > is created. > > ACK: > 1. From LB Node > 2. Hits internal interface of LB, the state is already there. > 3. Normal routing decision of LB decides to send the packet to IP stack. > 4. The packet never hits the pf state on the public side of LB. > 5. The public side pf state never sees ACK from the LB Node, the state > times out very fast. > > My goal is to have loadbalanced connections to *always* behave like they > come from the Internet, that is to leave the LB and bounce off the core > router. I'm not a pf user, so I wonder: why do you need to create any firewall state for such traffic at all? Can't you route such packets in stateless mode? I don't see any value in pf states for such packets.