From owner-freebsd-net@freebsd.org Sun Jan 19 13:47:49 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 7C42E1FA6F9 for ; Sun, 19 Jan 2020 13:47:49 +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 480x2C6Zycz4KDG; Sun, 19 Jan 2020 13:47:47 +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=r+S1H0KabFSUbytiO09x/h3SEP9yzGQk1E95jeAxUnY=; b=EmNYnPejHhnIbowPhidXwNTFJF t0/N6UpCKdjshWrgK1JF0ZbKCpVpyHv9/DCydxQDTrRVAA0YRU8OaFkK9Mt6Kv+SXCdDspQM78lSF C+IELuFU2b3AVU1RC7iHwcSlA0M5KZMGKIEjQzuFTfkaYSa3ThVyN6iJ7DcIcr4EN83g=; Received: from vas by admin.sibptus.ru with local (Exim 4.92.3 (FreeBSD)) (envelope-from ) id 1itAvT-000KfU-5S; Sun, 19 Jan 2020 20:47:39 +0700 Date: Sun, 19 Jan 2020 20:47:39 +0700 From: Victor Sudakov To: Eugene Grosbein Cc: Michael Sierchio , "freebsd-net@freebsd.org" , "Andrey V. Elsukov" , Michael Tuexen Subject: Re: IPSec transport mode, mtu, fragmentation... Message-ID: <20200119134739.GA76629@admin.sibptus.ru> References: <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> <20200119071223.GA63055@admin.sibptus.ru> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Kj7319i9nmIyA2yE" Content-Disposition: inline In-Reply-To: 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: 480x2C6Zycz4KDG X-Spamd-Bar: -------- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=sibptus.ru header.s=20181118 header.b=EmNYnPej; 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]; 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(-1.78), 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 13:47:49 -0000 --Kj7319i9nmIyA2yE Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Eugene Grosbein wrote: > 19.01.2020 14:12, Victor Sudakov wrote: >=20 > > So this is most probably the artifact of if_enc. What is then the > > correct way to capture data with it? >=20 > This is documented behaviour of enc(4), see its manual page for descripti= on > of sysctl net.enc.{in|out}.ipsec_bpf_mask This description does not make much sense to me, there is neigher "inner header" nor "outer header" in transport mode. By trial and error I've figured out that "net.enc.out.ipsec_bpf_mask=3D1" is probably the answer. At least ICMP requests and replies are not duplicated any more. I still see lots of "dup ACKs" in Wireshark though. --=20 Victor Sudakov, VAS4-RIPE, VAS47-RIPN 2:5005/49@fidonet http://vas.tomsk.ru/ --Kj7319i9nmIyA2yE Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBAgAGBQJeJF37AAoJEA2k8lmbXsY0A2kH/RS91zTrADYvr1P58WPn7JfL vt7Mu6BDAeTIn/Knz4QaWvkdFK4UDv02SOsMQGurKUba4OXd8bjLxEDMRJAy6dZ2 JicdGANQHHWdsDLm/3+hE1tjZiAznoRsXymCbRS/DA6slWbJIrknSY8rsniNDw9V 1f+/peROgdg8v6EjqVvGttNgX1xsaNw3N2GoY5RAJS77SsGDzoJmbneKImXlaW9g /43G0QB4xkwFrUR8upsEeh9X58CjWuYk8k5iOZ/NYkRl1zKolIGF3UP3VsE9HTHH S3WtPKI55VtLWVqMdHMINZ9dlkBhpZTHJuPr3v5lszkma6sVt39fgh2kpNOf3yw= =3cf1 -----END PGP SIGNATURE----- --Kj7319i9nmIyA2yE--