From owner-freebsd-net@freebsd.org Tue Apr 3 10:56:19 2018 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 6BBF2F767B2 for ; Tue, 3 Apr 2018 10:56:19 +0000 (UTC) (envelope-from bu7cher@yandex.ru) Received: from forward100j.mail.yandex.net (forward100j.mail.yandex.net [IPv6:2a02:6b8:0:801:2::100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "forwards.mail.yandex.net", Issuer "Yandex CA" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id D783976D67 for ; Tue, 3 Apr 2018 10:56:18 +0000 (UTC) (envelope-from bu7cher@yandex.ru) Received: from mxback11g.mail.yandex.net (mxback11g.mail.yandex.net [IPv6:2a02:6b8:0:1472:2741:0:8b7:90]) by forward100j.mail.yandex.net (Yandex) with ESMTP id 69B495D84CD4; Tue, 3 Apr 2018 13:56:08 +0300 (MSK) Received: from smtp2p.mail.yandex.net (smtp2p.mail.yandex.net [2a02:6b8:0:1472:2741:0:8b6:7]) by mxback11g.mail.yandex.net (nwsmtp/Yandex) with ESMTP id n5IWgp4wdx-u84GTmgW; Tue, 03 Apr 2018 13:56:08 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1522752968; bh=536E+5iUT3xjq3HfarT3rsQr8r3/90Umei4gVOjs5RA=; h=Subject:From:To:References:Message-ID:Date:In-Reply-To; b=XgG8PBfbYe0HLzIWRfCfOsfF0dRJKUJSiRZcrLutQ5WMe9ysd+AABSadEYaFzRmfm 5Q/T7F3/bvmRphik4LI10Mf1Y9K/z2/Gwt8AEHJT2H3PL6W5419AhOCVCtuPmeZKub bjq5eA5HAz1mH7tmQT0yePPNjOXU73l4m8wvv2D8= Received: by smtp2p.mail.yandex.net (nwsmtp/Yandex) with ESMTPSA id a3ff76jIsN-u19mm7ki; Tue, 03 Apr 2018 13:56:01 +0300 (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client certificate not present) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1522752961; bh=536E+5iUT3xjq3HfarT3rsQr8r3/90Umei4gVOjs5RA=; h=Subject:From:To:References:Message-ID:Date:In-Reply-To; b=iioAaHSYvGWBKrtaIa0YJ8J+fOPMl8dnhAk2DEi+XX3aSOSz7DSeU5FuuaXWvvxaU qQXeCcu3C5NcpnF3BHIA5df5Jc49qnd++sJJLH9+INx596flUFXo7ws3+HOlpxwz2V tTsGnmrJHZ1N7H8XjS4neDi8CV2hp8ms1KdE2P/Q= Authentication-Results: smtp2p.mail.yandex.net; dkim=pass header.i=@yandex.ru Subject: Re: Questions about ipfw's dynamic rules' dyn_keepalive From: "Andrey V. Elsukov" To: Andrea Venturoli , freebsd-net@freebsd.org References: <04ad23ad-4020-7c07-8d75-eef6e84f4de8@netfence.it> <756b78e2-4e65-ab03-1e91-943a77fdf45d@yandex.ru> Openpgp: id=E6591E1B41DA1516F0C9BC0001C5EA0410C8A17A Autocrypt: addr=bu7cher@yandex.ru; keydata= xsBNBEwBF1kBCADB9sXFhBEUy8qQ4X63Y8eBatYMHGEFWN9ypS5lI3RE6qQW2EYbxNk7qUC5 21YIIS1mMFVBEfvR7J9uc7yaYgFCEb6Sce1RSO4ULN2mRKGHP3/Sl0ijZEjWHV91hY1YTHEF ZW/0GYinDf56sYpDDehaBF5wkWIo1+QK5nmj3vl0DIDCMNd7QEiWpyLVwECgLX2eOAXByT8B bCqVhJGcG6iFP7/B9Ll6uX5gb8thM9LM+ibwErDBVDGiOgvfxqidab7fdkh893IBCXa82H9N CNwnEtcgzh+BSKK5BgvPohFMgRwjti37TSxwLu63QejRGbZWSz3OK3jMOoF63tCgn7FvABEB AAHNIkFuZHJleSBWLiBFbHN1a292IDxhZUBmcmVlYnNkLm9yZz7CwHsEEwECACUCGwMGCwkI BwMCBhUIAgkKCwQWAgMBAh4BAheABQJMB/ruAhkBAAoJEAHF6gQQyKF6MLwH/3Ri/TZl9uo0 SepYWXOnxL6EaDVXDA+dLb1eLKC4PRBBjX29ttQ0KaWapiE6y5/AfzOPmRtHLrHYHjd/aiHX GMLHcYRXD+5GvdkK8iMALrZ28X0JXyuuZa8rAxWIWmCbYHNSBy2unqWgTI04Erodk90IALgM 9JeHN9sFqTM6zalrMnTzlcmel4kcjT3lyYw3vOKgoYLtsLhKZSbJoVVVlvRlGBpHFJI5AoYJ SyfXoN0rcX6k9X7Isp2K50YjqxV4v78xluh1puhwZyC0p8IShPrmrp9Oy9JkMX90o6UAXdGU KfdExJuGJfUZOFBTtNIMNIAKfMTjhpRhxONIr0emxxDOwE0ETAEXWQEIAJ2p6l9LBoqdH/0J PEFDY2t2gTvAuzz+8zs3R03dFuHcNbOwjvWCG0aOmVpAzkRa8egn5JB4sZaFUtKPYJEQ1Iu+ LUBwgvtXf4vWpzC67zs2dDuiW4LamH5p6xkTD61aHR7mCB3bg2TUjrDWn2Jt44cvoYxj3dz4 S49U1rc9ZPgD5axCNv45j72tggWlZvpefThP7xT1OlNTUqye2gAwQravXpZkl5JG4eOqJVIU X316iE3qso0iXRUtO7OseBf0PiVmk+wCahdreHOeOxK5jMhYkPKVn7z1sZiB7W2H2TojbmcK HZC22sz7Z/H36Lhg1+/RCnGzdEcjGc8oFHXHCxUAEQEAAcLAXwQYAQIACQUCTAEXWQIbDAAK CRABxeoEEMihegkYCAC3ivGYNe2taNm/4Nx5GPdzuaAJGKWksV+w9mo7dQvU+NmI2az5w8vw 98OmX7G0OV9snxMW+6cyNqBrVFTu33VVNzz9pnqNCHxGvj5dL5ltP160JV2zw2bUwJBYsgYQ WfyJJIM7l3gv5ZS3DGqaGIm9gOK1ANxfrR5PgPzvI9VxDhlr2juEVMZYAqPLEJe+SSxbwLoz BcFCNdDAyXcaAzXsx/E02YWm1hIWNRxanAe7Vlg7OL+gvLpdtrYCMg28PNqKNyrQ87LQ49O9 50IIZDOtNFeR0FGucjcLPdS9PiEqCoH7/waJxWp6ydJ+g4OYRBYNM0EmMgy1N85JJrV1mi5i Message-ID: <25e56a77-8374-d273-0b5e-2f11c1b03ff8@yandex.ru> Date: Tue, 3 Apr 2018 13:54:36 +0300 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <756b78e2-4e65-ab03-1e91-943a77fdf45d@yandex.ru> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="3pbQzHjYyhniEXlwlsr6Lwxvkwk8YBPgc" X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 Apr 2018 10:56:19 -0000 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --3pbQzHjYyhniEXlwlsr6Lwxvkwk8YBPgc Content-Type: multipart/mixed; boundary="4EddIKeF57tY2C80Kd1IsdE9o5wOLvujc"; protected-headers="v1" From: "Andrey V. Elsukov" To: Andrea Venturoli , freebsd-net@freebsd.org Message-ID: <25e56a77-8374-d273-0b5e-2f11c1b03ff8@yandex.ru> Subject: Re: Questions about ipfw's dynamic rules' dyn_keepalive References: <04ad23ad-4020-7c07-8d75-eef6e84f4de8@netfence.it> <756b78e2-4e65-ab03-1e91-943a77fdf45d@yandex.ru> In-Reply-To: <756b78e2-4e65-ab03-1e91-943a77fdf45d@yandex.ru> --4EddIKeF57tY2C80Kd1IsdE9o5wOLvujc Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 03.04.2018 13:45, Andrey V. Elsukov wrote: >> Can anybody give any hint about the above behaviours or point me to go= od >> documentation? The man pages is very brief on this, unfortunately. >=20 > Hi, >=20 > ipfw uses M_SKIP_FIREWALL flag for self-generated packets. Thus > keep-alive packets are sent bypass the rules. When you use NAT, I guess= > keep-alive packets have private source address, because they are not go= > through the NAT rule. And because of this remote host drops them withou= t > reply. Since there are no replies to keep-alive requests, a state times= > out. You can try this patch: https://people.freebsd.org/~ae/ipfw_bypass_own_packets11.diff It adds sysctl variable net.inet.ip.fw.bypass_own_packets, that can control the behavior of M_SKIP_FIREWALL flag. --=20 WBR, Andrey V. Elsukov --4EddIKeF57tY2C80Kd1IsdE9o5wOLvujc-- --3pbQzHjYyhniEXlwlsr6Lwxvkwk8YBPgc 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 - http://www.enigmail.net/ iQEzBAEBCAAdFiEE5lkeG0HaFRbwybwAAcXqBBDIoXoFAlrDXWwACgkQAcXqBBDI oXpbqAf+NRhtkcCMY6lGmQ7nNf0lToYiC/rsz+vVCOY8x9b5FuM/3l05iNFDOS/T Qb52mOrC4iOTmLgeYBeKrciXPXUTL3JaVoQE9CGBj5SW3PAGO5cwWgfxOLitjMYj 5w6NSJ0PjXleJzNOSUCaMxxWzP0//K9JZLGdmv76ncgQj6v3NtwaIyiyxnDBEA8K gps71HHiURzw9BTyhAiDxf5wKLugefDdQ7wC+c/XNEAKJ3pyIam3ZURlDBfrqe5G 8ghOHIj3JbGXNhVR29B27jbtxIL3L68s3RaXMjVzA8UAE3UetZh4FWlM0GtYJJym sWfXCaYdlmhYIGifiI7ZmcWQctztTw== =S7Yi -----END PGP SIGNATURE----- --3pbQzHjYyhniEXlwlsr6Lwxvkwk8YBPgc--