From nobody Mon Dec 6 17:40:10 2021 X-Original-To: freebsd-net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 73B2918C89DE for ; Mon, 6 Dec 2021 17:40:21 +0000 (UTC) (envelope-from freebsd-rwg@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 4J79gS0CGPz3nZV; Mon, 6 Dec 2021 17:40:19 +0000 (UTC) (envelope-from freebsd-rwg@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 1B6HeBId065574; Mon, 6 Dec 2021 09:40:11 -0800 (PST) (envelope-from freebsd-rwg@gndrsh.dnsmgr.net) Received: (from freebsd-rwg@localhost) by gndrsh.dnsmgr.net (8.13.3/8.13.3/Submit) id 1B6HeA79065573; Mon, 6 Dec 2021 09:40:10 -0800 (PST) (envelope-from freebsd-rwg) From: "Rodney W. Grimes" Message-Id: <202112061740.1B6HeA79065573@gndrsh.dnsmgr.net> Subject: Re: Porting OpenBSD MPLS to FreeBSD In-Reply-To: To: Neel Chauhan Date: Mon, 6 Dec 2021 09:40:10 -0800 (PST) CC: "Alexander V. Chernikov" , freebsd-net@FreeBSD.org X-Mailer: ELM [version 2.4ME+ PL121h (25)] List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@freebsd.org MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII X-Rspamd-Queue-Id: 4J79gS0CGPz3nZV X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=none (mx1.freebsd.org: domain of freebsd-rwg@gndrsh.dnsmgr.net has no SPF policy when checking 69.59.192.140) smtp.mailfrom=freebsd-rwg@gndrsh.dnsmgr.net X-Spamd-Result: default: False [0.61 / 15.00]; RCVD_TLS_LAST(0.00)[]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-0.99)[-0.992]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; TO_DN_SOME(0.00)[]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[dnsmgr.net]; AUTH_NA(1.00)[]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_HAM_SHORT(-0.21)[-0.205]; NEURAL_SPAM_LONG(0.91)[0.911]; R_SPF_NA(0.00)[no SPF record]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:13868, ipnet:69.59.192.0/19, country:US]; RCVD_COUNT_TWO(0.00)[2]; MID_RHS_MATCH_FROM(0.00)[] X-ThisMailContainsUnwantedMimeParts: N [ Charset UTF-8 unsupported, converting... ] > Hi Alexander, > > On 2021-12-04 10:42, Alexander V. Chernikov wrote: > >> * Is porting OpenBSD MPLS to FreeBSD feasible, or are we better off > >> doing a from-scratch implementation based on netgraph? > > It depends. MPLS implementaiton can be splitted into multiple logical > > parts - dataplane (input, control, output, forward) and control plane > > (programming ip routes+mpls and mpls-only fowarding state). Some parts > > of the former can indeed be imported from OpenBSD. However, most of > > the control plane part have to be written from scratch. Finally, it > > may be desired to maintain an programming interface close to the one > > already implemented in major routing SW (frr, bird) - I guess that > > would be simpler to achieve with native, non-netgraph implementation. > > Thanks for your description. I haven't started work yet, but I'd > probably import the dataplane from OpenBSD where I can and do a new > control plane, maybe that with a FRR/Bird-compatible API. When you get to working with FRR let me know, I am a member of the CI infustructure team there and can hook you up directly with very knowledgeable FRR developers. > > I wasn't too keen on using netgraph anyways, I felt it was unnecessary > complexity. True, but with that complexity comes an ulmost unlimited flexiablity. > If I were to work on this, would I be better off starting with the > dataplane or control plane? I concur with Alexander on this, dataplace first, with an eye on how FRR/Bird interact with the dataplane. > > >> * Would some of the other committers here be willing to mentor/help me > >> if needed? > > I?d love to. Most of my the routing-related stack changes (modular > > lookup framework, nexthops, rtsock cleanups) were done to enable > > efficient kernel-based MPLS implementation. > > Thanks! > > -Neel (nc@) > > -- Rod Grimes rgrimes@freebsd.org