From nobody Fri Jun 14 17:26:37 2024 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 4W15mh1vMWz5PD6F for ; Fri, 14 Jun 2024 17:26:44 +0000 (UTC) (envelope-from freebsd-rwg@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (pdx.rh.CN85.dnsmgr.net [65.75.216.6]) (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 4W15mg5skbz43nx; Fri, 14 Jun 2024 17:26:43 +0000 (UTC) (envelope-from freebsd-rwg@gndrsh.dnsmgr.net) Authentication-Results: mx1.freebsd.org; none Received: from gndrsh.dnsmgr.net (localhost [127.0.0.1]) by gndrsh.dnsmgr.net (8.13.3/8.13.3) with ESMTP id 45EHQboN050039; Fri, 14 Jun 2024 10:26:37 -0700 (PDT) (envelope-from freebsd-rwg@gndrsh.dnsmgr.net) Received: (from freebsd-rwg@localhost) by gndrsh.dnsmgr.net (8.13.3/8.13.3/Submit) id 45EHQbY7050038; Fri, 14 Jun 2024 10:26:37 -0700 (PDT) (envelope-from freebsd-rwg) From: "Rodney W. Grimes" Message-Id: <202406141726.45EHQbY7050038@gndrsh.dnsmgr.net> Subject: Re: Discarding inbound ICMP REDIRECT by default In-Reply-To: To: Ed Maste Date: Fri, 14 Jun 2024 10:26:37 -0700 (PDT) CC: "Rodney W. Grimes" , 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-Spamd-Bar: ---- X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:10494, ipnet:65.75.216.0/23, country:US] X-Rspamd-Queue-Id: 4W15mg5skbz43nx > On Fri, 14 Jun 2024 at 11:13, Rodney W. Grimes > wrote: > > > > That section is about how the router responds to an ICMP redirect > > set to IT, not one that is going THROUGH it. > > Sorry I wasn't explicit, in all cases I'm talking about ICMP REDIRECTs > destined for the machine (as a host or as a router). This is > icmp_input dropping when either drop_redirect or ipforwarding is true. Ok, so long as we are not dropping ICMP REDIRECTS that are NOT destined for the router we are fine, which is the behavior I expected and observed on my network, though it is a bit older code. -- Rod Grimes rgrimes@freebsd.org