From owner-freebsd-net@freebsd.org Mon Dec 23 11:02:06 2019 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 8D41A1EC8CA for ; Mon, 23 Dec 2019 11:02:06 +0000 (UTC) (envelope-from bu7cher@yandex.ru) Received: from forward104j.mail.yandex.net (forward104j.mail.yandex.net [IPv6:2a02:6b8:0:801:2::107]) (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 47hGdT3KfKz4W86; Mon, 23 Dec 2019 11:02:04 +0000 (UTC) (envelope-from bu7cher@yandex.ru) Received: from mxback18j.mail.yandex.net (mxback18j.mail.yandex.net [IPv6:2a02:6b8:0:1619::94]) by forward104j.mail.yandex.net (Yandex) with ESMTP id 8B3E04A14F3; Mon, 23 Dec 2019 14:01:53 +0300 (MSK) Received: from sas8-6bf5c5d991b2.qloud-c.yandex.net (sas8-6bf5c5d991b2.qloud-c.yandex.net [2a02:6b8:c1b:2a1f:0:640:6bf5:c5d9]) by mxback18j.mail.yandex.net (mxback/Yandex) with ESMTP id X3FQbowLMn-1qOuXXva; Mon, 23 Dec 2019 14:01:53 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1577098913; bh=38h/PgsX4rFRARWQ/v5jJNGPSqzqZbsoOROgVaMxrTQ=; h=In-Reply-To:From:To:Subject:Cc:Date:References:Message-ID; b=O165HTmfKZ5oGocT7ukybxOeTXcBiyLGOrO8fJo5wa7wxJBAvdd29XX4fmAgznX+J qwdpY2bVtFsVYAs4ZswcOMKBjgJMSKPRl7aY8/OEUYRwiF1dQ+mHY0n0yahQTeznaq 8HkkPpfu7dpE5XZhUaNIBvp+ZPon3wpYqNQXXOXs= Received: by sas8-6bf5c5d991b2.qloud-c.yandex.net (smtp/Yandex) with ESMTPSA id e4jnaySn9K-1qWu4Tu7; Mon, 23 Dec 2019 14:01:52 +0300 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (Client certificate not present) Subject: Re: IPSec transport mode, mtu, fragmentation... To: Eugene Grosbein , Victor Sudakov Cc: freebsd-net@freebsd.org, Michael Tuexen References: <20191220152314.GA55278@admin.sibptus.ru> <20191220160357.GB56081@admin.sibptus.ru> <20191220162233.GA56815@admin.sibptus.ru> <55eeca4c-9633-339a-f521-b0db462cc1d6@yandex.ru> <20191223100655.GA41651@admin.sibptus.ru> <3edbc7ad-a760-48c7-3222-202d7a835fe5@yandex.ru> <35fd51d5-c171-c97c-5bb2-529912d75844@grosbein.net> From: "Andrey V. Elsukov" Openpgp: id=E6591E1B41DA1516F0C9BC0001C5EA0410C8A17A Autocrypt: addr=bu7cher@yandex.ru; prefer-encrypt=mutual; keydata= mQENBEwBF1kBCADB9sXFhBEUy8qQ4X63Y8eBatYMHGEFWN9ypS5lI3RE6qQW2EYbxNk7qUC5 21YIIS1mMFVBEfvR7J9uc7yaYgFCEb6Sce1RSO4ULN2mRKGHP3/Sl0ijZEjWHV91hY1YTHEF ZW/0GYinDf56sYpDDehaBF5wkWIo1+QK5nmj3vl0DIDCMNd7QEiWpyLVwECgLX2eOAXByT8B bCqVhJGcG6iFP7/B9Ll6uX5gb8thM9LM+ibwErDBVDGiOgvfxqidab7fdkh893IBCXa82H9N CNwnEtcgzh+BSKK5BgvPohFMgRwjti37TSxwLu63QejRGbZWSz3OK3jMOoF63tCgn7FvABEB AAG0JUFuZHJleSBWLiBFbHN1a292IDxidTdjaGVyQHlhbmRleC5ydT6JATgEEwECACIFAkwB F1kCGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEAHF6gQQyKF6qmYIAI6ekfm1VA4T vqankI1ISE6ku4jV7UlpIQlEbE7/8n3Zd6teJ+pGOQhN5qk8QE7utdPdbktAzi+x7LIJVzUw 4TywZLXGrkP7VKYkfg6oyCGyzITghefQeJtr2TN4hYCkzPWpylkue8MtmqfZv/6royqwTbN+ +E09FQNvTgRUYJYTeQ1qOsxNRycwvw3dr2rOfuxShbzaHBB1pBIjGrMg8fC5pd65ACH5zuFV A0CoTNGMDrEZSfBkTW604UUHFFXeCoC3dwDZRKOWJ3GmMXns65Ai5YkA63BSHEE1Qle3VBhd cG1w0CB5FBV3pB27UVnf0jEbysrDqW4qN7XMRFSWNAy5AQ0ETAEXWQEIAJ2p6l9LBoqdH/0J PEFDY2t2gTvAuzz+8zs3R03dFuHcNbOwjvWCG0aOmVpAzkRa8egn5JB4sZaFUtKPYJEQ1Iu+ LUBwgvtXf4vWpzC67zs2dDuiW4LamH5p6xkTD61aHR7mCB3bg2TUjrDWn2Jt44cvoYxj3dz4 S49U1rc9ZPgD5axCNv45j72tggWlZvpefThP7xT1OlNTUqye2gAwQravXpZkl5JG4eOqJVIU X316iE3qso0iXRUtO7OseBf0PiVmk+wCahdreHOeOxK5jMhYkPKVn7z1sZiB7W2H2TojbmcK HZC22sz7Z/H36Lhg1+/RCnGzdEcjGc8oFHXHCxUAEQEAAYkBHwQYAQIACQUCTAEXWQIbDAAK CRABxeoEEMihegkYCAC3ivGYNe2taNm/4Nx5GPdzuaAJGKWksV+w9mo7dQvU+NmI2az5w8vw 98OmX7G0OV9snxMW+6cyNqBrVFTu33VVNzz9pnqNCHxGvj5dL5ltP160JV2zw2bUwJBYsgYQ WfyJJIM7l3gv5ZS3DGqaGIm9gOK1ANxfrR5PgPzvI9VxDhlr2juEVMZYAqPLEJe+SSxbwLoz BcFCNdDAyXcaAzXsx/E02YWm1hIWNRxanAe7Vlg7OL+gvLpdtrYCMg28PNqKNyrQ87LQ49O9 50IIZDOtNFeR0FGucjcLPdS9PiEqCoH7/waJxWp6ydJ+g4OYRBYNM0EmMgy1N85JJrV1mi5i Message-ID: Date: Mon, 23 Dec 2019 14:00:16 +0300 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <35fd51d5-c171-c97c-5bb2-529912d75844@grosbein.net> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="UCStypbEvRrpA0iymJIG0giG88It5b8oJ" X-Rspamd-Queue-Id: 47hGdT3KfKz4W86 X-Spamd-Bar: ------ Authentication-Results: mx1.freebsd.org; dkim=pass header.d=yandex.ru header.s=mail header.b=O165HTmf; dmarc=pass (policy=none) header.from=yandex.ru; spf=pass (mx1.freebsd.org: domain of bu7cher@yandex.ru designates 2a02:6b8:0:801:2::107 as permitted sender) smtp.mailfrom=bu7cher@yandex.ru X-Spamd-Result: default: False [-6.20 / 15.00]; TO_DN_SOME(0.00)[]; FREEMAIL_FROM(0.00)[yandex.ru]; R_SPF_ALLOW(-0.20)[+ip6:2a02:6b8:0::/52:c]; HAS_ATTACHMENT(0.00)[]; RCVD_COUNT_THREE(0.00)[3]; DKIM_TRACE(0.00)[yandex.ru:+]; DMARC_POLICY_ALLOW(-0.50)[yandex.ru,none]; SIGNED_PGP(-2.00)[]; FROM_EQ_ENVFROM(0.00)[]; IP_SCORE(0.00)[ip: (-9.58), ipnet: 2a02:6b8::/32(-4.71), asn: 13238(-3.79), country: RU(0.01)]; MIME_TRACE(0.00)[0:+,1:+,2:+,3:~]; FREEMAIL_ENVFROM(0.00)[yandex.ru]; ASN(0.00)[asn:13238, ipnet:2a02:6b8::/32, country:RU]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_IN_DNSWL_LOW(-0.10)[7.0.1.0.0.0.0.0.0.0.0.0.2.0.0.0.1.0.8.0.0.0.0.0.8.b.6.0.2.0.a.2.list.dnswl.org : 127.0.5.1]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; R_DKIM_ALLOW(-0.20)[yandex.ru:s=mail]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[4]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.20)[multipart/signed,multipart/mixed,text/plain]; RCVD_TLS_LAST(0.00)[]; IP_SCORE_FREEMAIL(0.00)[]; DWL_DNSWL_LOW(-1.00)[yandex.ru.dwl.dnswl.org : 127.0.5.1]; TO_MATCH_ENVRCPT_SOME(0.00)[] 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: Mon, 23 Dec 2019 11:02:06 -0000 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --UCStypbEvRrpA0iymJIG0giG88It5b8oJ Content-Type: multipart/mixed; boundary="BjGOyLNd8gyyJel40COoVHXrSIwzmhsdG"; protected-headers="v1" From: "Andrey V. Elsukov" To: Eugene Grosbein , Victor Sudakov Cc: freebsd-net@freebsd.org, Michael Tuexen Message-ID: Subject: Re: IPSec transport mode, mtu, fragmentation... References: <20191220152314.GA55278@admin.sibptus.ru> <20191220160357.GB56081@admin.sibptus.ru> <20191220162233.GA56815@admin.sibptus.ru> <55eeca4c-9633-339a-f521-b0db462cc1d6@yandex.ru> <20191223100655.GA41651@admin.sibptus.ru> <3edbc7ad-a760-48c7-3222-202d7a835fe5@yandex.ru> <35fd51d5-c171-c97c-5bb2-529912d75844@grosbein.net> In-Reply-To: <35fd51d5-c171-c97c-5bb2-529912d75844@grosbein.net> --BjGOyLNd8gyyJel40COoVHXrSIwzmhsdG Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 23.12.2019 13:55, Eugene Grosbein wrote: >> I think the real problem is that PMTUD doesn't work correctly with >> IPsec. Linux has special sysctl variabl ip_no_pmtu_disc and flag >> SADB_SAFLAGS_NOPMTUDISC for SA that can disable PMTUD for IPv4 and IP_= DF >> flag will not be set. We can add some similar quirks, but it would be >> better to fix PMTUD. We already have hundreds sysctl in our system and= >> remembering all them is a problem too. >=20 > It's true that PMTUD does not work with IPSec transport mode. >=20 > I think we could just clear DF bit off encapsulated transport mode pack= ets unconditionally, > please take a look at last chunk of sample patch in the PR 242744: > https://bz-attachments.freebsd.org/attachment.cgi?id=3D210122 >=20 > Sample patch creates another sysctl but we should do it unconditionally= , don't we? As I said I didn't find that other OSes do this. Linux has enabled by PMTUD by default, strongswan doesn't set SADB_SAFLAGS_NOPMTUDISC flag, OpenBSD hasn't such quirk. Why should we add this instead of try to fix PMTUD? --=20 WBR, Andrey V. Elsukov --BjGOyLNd8gyyJel40COoVHXrSIwzmhsdG-- --UCStypbEvRrpA0iymJIG0giG88It5b8oJ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Comment: Using GnuPG with Thunderbird - https://www.enigmail.net/ iQEyBAEBCAAdFiEE5lkeG0HaFRbwybwAAcXqBBDIoXoFAl4AnkAACgkQAcXqBBDI oXrJXQf4qb/Ev25S+z0C1LTleyhJoiGsCJGtOeAufeEzdDYaVLM5VlAVlsO6jNsO /fkZxq+TMSaAYTdOn6WxRhDHC6aiNkBOP34X+OvIaDULJ+eMQf0t/O3UZtQ1j7ev NuxZwSBwKPh/dC0fDD+fNjMa0DkrqOM3C5jYyD9B00G3yywLisD1GgZtBj1qghC0 nvmGAoZpnfodmBUPWjhihICHFa1Vff2xDVQu+7ez+kB1glNp5qWVf8DcCrCwpIB7 Ah9Kmo7EpBLTEMME3/MQPfN9J0xkpajGdUL7gWKMjQzYjQjBHYF7eE4T5ZSQps+c S035jVxaOe6VuXbdih7hlG9up1Hk =HaMU -----END PGP SIGNATURE----- --UCStypbEvRrpA0iymJIG0giG88It5b8oJ--