From owner-svn-src-all@freebsd.org Sat Aug 20 23:42:34 2016 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 731C8BC09AC; Sat, 20 Aug 2016 23:42:34 +0000 (UTC) (envelope-from bms@fastmail.net) Received: from out2-smtp.messagingengine.com (out2-smtp.messagingengine.com [66.111.4.26]) (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 3B4FB188C; Sat, 20 Aug 2016 23:42:33 +0000 (UTC) (envelope-from bms@fastmail.net) Received: from compute2.internal (compute2.nyi.internal [10.202.2.42]) by mailout.nyi.internal (Postfix) with ESMTP id B41812060F; Sat, 20 Aug 2016 19:42:32 -0400 (EDT) Received: from frontend2 ([10.202.2.161]) by compute2.internal (MEProxy); Sat, 20 Aug 2016 19:42:32 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=fastmail.net; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-sasl-enc :x-sasl-enc; s=mesmtp; bh=WAl1E+q9SPAnri9ThpISU7pyAq0=; b=DNfhFr I4cbJgAofhUGEG2zytJZgwi7/EMH/FgM4yraV+UbHr4IFxhws1rwdHbs6/+0Ope9 gN+9csSFkyEQPNVVfHyovBvwiKkmbRYo2saMagOqNYm+lDJNj4w69mwm9JjOOIh4 iggXU6IOvkHXfYc5Ft7t8WA0JRp3/B6pzXKJk= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-sasl-enc:x-sasl-enc; s=smtpout; bh=WAl1E+q9SPAnri9 ThpISU7pyAq0=; b=Hl0XYto+5ddXxL+ijx78+KiWnNHsrlK/8+uMPXEj2Pp06vU FdUr577/FWfQXwDRg5+1TEylnbOEIv+b8ckAlf6UpJc5Cjg4YicrXb7KxP7os9AP HMg+W/eOtO8PgbE+GJrHH+5p4J3TWFb5NozXtVV3cQrGfvviUp3Dd4irtIPQ= X-Sasl-enc: H4QZNNI+5FvuL2/TX9NrZ/f+aYP/9ePmyBcUZuOE0jx9 1471736552 Received: from pion.local (cpc96954-walt26-2-0-cust843.13-2.cable.virginm.net [82.31.91.76]) by mail.messagingengine.com (Postfix) with ESMTPA id 9F9D5CCE6E; Sat, 20 Aug 2016 19:42:31 -0400 (EDT) Subject: Re: svn commit: r304436 - in head: . sys/netinet To: Slawa Olhovchenkov References: <6f4449f2-d145-8b49-c3f0-433e8ff4d2a2@fastmail.net> <20160820173050.GQ22212@zxy.spb.ru> <20160820184506.GV8192@zxy.spb.ru> <0f42c5fb-f930-c6e3-75d6-df97f67c201d@fastmail.net> <20160820204106.GW8192@zxy.spb.ru> <0acba141-4701-d9c2-0ddb-46d1f60ff55b@fastmail.net> <20160820220510.GX8192@zxy.spb.ru> <8ac23bd1-dcb3-7c64-f195-5039f9af0eaf@fastmail.net> Cc: Ryan Stone , "svn-src-head@freebsd.org" , Ryan Stone , "src-committers@freebsd.org" , "svn-src-all@freebsd.org" , Adrian Chadd From: Bruce Simpson Message-ID: <1ebf4e2c-5fa1-29bc-0dc9-7ee2d7e2dc59@fastmail.net> Date: Sun, 21 Aug 2016 00:42:23 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <8ac23bd1-dcb3-7c64-f195-5039f9af0eaf@fastmail.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 20 Aug 2016 23:42:34 -0000 On 21/08/16 00:25, Bruce Simpson wrote: > On 20/08/16 23:05, Slawa Olhovchenkov wrote: >> In router case receiving broadcast packet in any way need additional >> check for dst IP address (host part is all zero or all one? what about >> handling this broadcast type (RFC talk about conroling variation of >> this)? what about sysctl control of receiving routed broadcast >> packets? what about handling 255.255.255.255?) > > I believe most of this is already special-cased in ip_fastfwd.c (which > gnn@ of course has merged, as it's full of sensible FIB-like operators > which most router forwarding planes adopt on *their* IP input paths up > to the forwarding decision), assuming the Ethernet input path colours > packets with the right flags. Just for reference, many of these 'sensible FIB operators' in the former ip_fastfwd.c came from the experience of James Jun at Towardex Systems. I merged his patch on the job whilst staying in Berkeley, CA and working on XORP at ICSI. I was only too happy to do that on their ticket, as it covered a lot of little performance cases which the pure rtalloc() fallthrough made us wince about.