From owner-freebsd-net@freebsd.org Sun Jan 19 07:12:29 2020 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 1667423695F for ; Sun, 19 Jan 2020 07:12:29 +0000 (UTC) (envelope-from vas@sibptus.ru) Received: from admin.sibptus.ru (admin.sibptus.ru [IPv6:2001:19f0:5001:21dc::10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 480mG30WyRz3wsT; Sun, 19 Jan 2020 07:12:26 +0000 (UTC) (envelope-from vas@sibptus.ru) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sibptus.ru; s=20181118; h=In-Reply-To:Message-ID:Subject:To:From:Date; bh=8YcD6gNPQpspuKqdPxoNul4M5A+4dzRb8aZjZATGMH8=; b=BsRHcKcDuFml+1kXGkMpNsiBmO qXRBB9lAknC2MSevevqC26pnkTED0es6g5e74ycKGJesX7UiA0zaEq0Hy3LpC+84Q5AgOoWZGzpyp 0sxfsKuhqZ4Dzr0p88s+isAOY9KuYAjLTVOAk0e1AeuTj+FrwhIexyfGi+cjeGliUk4A=; Received: from vas by admin.sibptus.ru with local (Exim 4.92.3 (FreeBSD)) (envelope-from ) id 1it4kx-000GSu-UG; Sun, 19 Jan 2020 14:12:23 +0700 Date: Sun, 19 Jan 2020 14:12:23 +0700 From: Victor Sudakov To: Michael Sierchio Cc: Eugene Grosbein , "freebsd-net@freebsd.org" , "Andrey V. Elsukov" , Michael Tuexen Subject: Re: IPSec transport mode, mtu, fragmentation... Message-ID: <20200119071223.GA63055@admin.sibptus.ru> References: <20200116160745.GA1356@admin.sibptus.ru> <72355e03-1cf8-c58f-3aec-b0a21e631870@grosbein.net> <20200117093645.GA51899@admin.sibptus.ru> <70b0b855-189b-03c2-0712-fc1e35640702@grosbein.net> <20200117150928.GB66677@admin.sibptus.ru> <16550199-67b9-d331-0c1e-4afa0e8b361c@grosbein.net> <20200118105524.GA10042@admin.sibptus.ru> <20200119033645.GA54797@admin.sibptus.ru> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ibTvN161/egqYuK8" Content-Disposition: inline In-Reply-To: <20200119033645.GA54797@admin.sibptus.ru> X-PGP-Key: http://admin.sibptus.ru/~vas/ X-PGP-Fingerprint: 10E3 1171 1273 E007 C2E9 3532 0DA4 F259 9B5E C634 X-Rspamd-Queue-Id: 480mG30WyRz3wsT X-Spamd-Bar: -------- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=sibptus.ru header.s=20181118 header.b=BsRHcKcD; dmarc=pass (policy=none) header.from=sibptus.ru; spf=pass (mx1.freebsd.org: domain of vas@sibptus.ru designates 2001:19f0:5001:21dc::10 as permitted sender) smtp.mailfrom=vas@sibptus.ru X-Spamd-Result: default: False [-8.43 / 15.00]; ARC_NA(0.00)[]; TO_DN_EQ_ADDR_SOME(0.00)[]; R_DKIM_ALLOW(-0.20)[sibptus.ru:s=20181118]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+mx:c]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.20)[multipart/signed,text/plain]; IP_SCORE(-3.33)[ip: (-9.89), ipnet: 2001:19f0:5000::/38(-4.94), asn: 20473(-1.77), country: US(-0.05)]; RCPT_COUNT_FIVE(0.00)[5]; TO_MATCH_ENVRCPT_SOME(0.00)[]; DKIM_TRACE(0.00)[sibptus.ru:+]; DMARC_POLICY_ALLOW(-0.50)[sibptus.ru,none]; SIGNED_PGP(-2.00)[]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+,1:+,2:~]; RCVD_TLS_LAST(0.00)[]; ASN(0.00)[asn:20473, ipnet:2001:19f0:5000::/38, country:US]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 19 Jan 2020 07:12:29 -0000 --ibTvN161/egqYuK8 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Victor Sudakov wrote: > Michael Sierchio wrote: > >=20 > > What is the result of > >=20 > > > sysctl net.enc >=20 > ot@fbsd-test1:~ # sysctl net.enc > net.enc.out.ipsec_bpf_mask: 3 > net.enc.out.ipsec_filter_mask: 0 > net.enc.in.ipsec_bpf_mask: 1 > net.enc.in.ipsec_filter_mask: 0 >=20 > >=20 > > ? This might be a clue about the packets, which you could be seeing tw= ice. > >=20 >=20 > An artifact of enc0, you think ? Are the above settings sending the > packets to if_enc twice? I just made a small experiment: sent 20 pings from 192.168.246.10 to 192.168.246.11, and I see that each echo reply is duplicated, so there are 60 packets totally in the traffic dump: 20 requests and 40 replies: http://admin.sibptus.ru/~vas/i1.pcap So this is most probably the artifact of if_enc. What is then the correct way to capture data with it? --=20 Victor Sudakov, VAS4-RIPE, VAS47-RIPN 2:5005/49@fidonet http://vas.tomsk.ru/ --ibTvN161/egqYuK8 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBAgAGBQJeJAFXAAoJEA2k8lmbXsY0GDAH/1bCdb6quw4mRu73ra67rmyZ zqTx4deZmO0PFpN497QfCVBlbKfr7Fi983/D43yryplrljNFt7OO0AuRu2zcnJrY sB+PpDgVz2dwmhg8+CXKRjL25ppAT7Er6hEk0Jf/f7AfxoWOxGMy/vL5y/yBLrsX gtqSFZE5UtnjQqKR2pRiubBEwczTpgW+ZQiHVtFQ1OBBGnuzqFaRoxmfsOeJnMT3 MHL7IepYsbi5+HRuNl5IOQUnY5aKRPX9YkhnTElYKUehO5XVaHxKKjgj8I9kbSrH 1iGgLWDGJdbuP6iiUJnYuzD47NvfjgGAKiz+wh/xTiKkVoRFHENsJjLhkpPsfZs= =HS2S -----END PGP SIGNATURE----- --ibTvN161/egqYuK8--