From owner-svn-src-all@freebsd.org Tue May 21 01:10:27 2019 Return-Path: Delivered-To: svn-src-all@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 19BB7159924D; Tue, 21 May 2019 01:10:27 +0000 (UTC) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (br1.CN84in.dnsmgr.net [69.59.192.140]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 690256CB52; Tue, 21 May 2019 01:10:26 +0000 (UTC) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (localhost [127.0.0.1]) by gndrsh.dnsmgr.net (8.13.3/8.13.3) with ESMTP id x4L1ALWi076421; Mon, 20 May 2019 18:10:21 -0700 (PDT) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: (from freebsd@localhost) by gndrsh.dnsmgr.net (8.13.3/8.13.3/Submit) id x4L1AL4I076420; Mon, 20 May 2019 18:10:21 -0700 (PDT) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <201905210110.x4L1AL4I076420@gndrsh.dnsmgr.net> Subject: Re: svn commit: r347982 - head/sys/net In-Reply-To: <17209181558392377@myt4-ea6eba8eca77.qloud-c.yandex.net> To: "Alexander V. Chernikov" Date: Mon, 20 May 2019 18:10:21 -0700 (PDT) CC: "rgrimes@freebsd.org" , "src-committers@freebsd.org" , "svn-src-all@freebsd.org" , "svn-src-head@freebsd.org" Reply-To: rgrimes@freebsd.org X-Mailer: ELM [version 2.4ME+ PL121h (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII X-Rspamd-Queue-Id: 690256CB52 X-Spamd-Bar: ------ Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-6.97 / 15.00]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; REPLY(-4.00)[]; NEURAL_HAM_SHORT(-0.97)[-0.971,0] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 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: Tue, 21 May 2019 01:10:27 -0000 > 20.05.2019, 07:50, "Rodney W. Grimes" : > >> ?Author: melifaro > >> ?Date: Sun May 19 21:49:56 2019 > >> ?New Revision: 347982 > >> ?URL: https://svnweb.freebsd.org/changeset/base/347982 > >> > >> ?Log: > >> ???Fix rt_ifa selection during loopback route insertion process. > >> ?????Currently such routes are added with a link-level IFA, which is > >> ?????plain wrong. Only after the insertion they get fixed by the special > >> ?????link_rtrequest() ifa handler. This behaviour complicates routing code > >> ?????and makes ifa selection more complex. > >> ???Streamline this process by explicitly moving link_rtrequest() logic > >> ?????to the pre-insertion rt_getifa_fib() ifa selector. Avoid calling all > >> ?????this logic in the loopback route case by explicitly specifying > >> ?????proper rt_ifa inside the ifa_maintain_loopback_route().? > >> > >> ???MFC after: 2 weeks > >> ???Differential Revision: https://reviews.freebsd.org/D20076 > > > > I shall again state that from a routing protocol perspecitive > > and a POLA perspective having the kernel doing route maintanance > > of any kind is fundementally wrong. > > > > I still continue to stronly object to ifa_maintain_loopback_route > > code even being present in our kernel. Having these routes > > is a micro optimization at best, and cause issues when real > > and actual routing protocols are in use. > I agree with that. It indeed causes decent amount of complications and I (as another router type person) prefer to have it gone as well. > However, one has to carefully check uRPF functionality in our firewalls, implement fib-aware in_localip_more (and its IPv6 counterpart) to make it happen. How about we implement the simplest next step, make this behavior either a kernel compile time option with #ifdef, and/or a sysctl to turn it off with a bit that defaults to current behavior while we investigate the harder solution? > > Bruce Evans and myself have locally killed this code, and > > just about every router type person I show it to gets ill > > seeing it. > > > > Show many another system that does this and I might reconsider, > > but I have never ever seen one. > > > >> ?Modified: > >> ???head/sys/net/if.c > >> ???head/sys/net/route.c ... > > > > Rod Grimes rgrimes@freebsd.org -- Rod Grimes rgrimes@freebsd.org