From owner-freebsd-bugs@FreeBSD.ORG Mon Jan 1 09:40:23 2007 Return-Path: X-Original-To: freebsd-bugs@hub.freebsd.org Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 531BA16A4FB for ; Mon, 1 Jan 2007 09:40:23 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [69.147.83.40]) by mx1.freebsd.org (Postfix) with ESMTP id 032C313C45D for ; Mon, 1 Jan 2007 09:40:23 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1]) by freefall.freebsd.org (8.13.4/8.13.4) with ESMTP id l019eMHs040662 for ; Mon, 1 Jan 2007 09:40:22 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.13.4/8.13.4/Submit) id l019eMu3040661; Mon, 1 Jan 2007 09:40:22 GMT (envelope-from gnats) Date: Mon, 1 Jan 2007 09:40:22 GMT Message-Id: <200701010940.l019eMu3040661@freefall.freebsd.org> To: freebsd-bugs@FreeBSD.org From: Eugene Grosbein Cc: Subject: Re: kern/103135: ipsec with ipfw divert (not NAT) encodes a packet twice breaking PMTUD X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Eugene Grosbein List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 01 Jan 2007 09:40:23 -0000 The following reply was made to PR kern/103135; it has been noted by GNATS. From: Eugene Grosbein To: bug-followup@freebsd.org Cc: julian@elischer.org Subject: Re: kern/103135: ipsec with ipfw divert (not NAT) encodes a packet twice breaking PMTUD Date: Mon, 01 Jan 2007 15:52:26 +0700 Hi! I've found that when DUMMYNET reinjects a packet to the stack to pass it over next ipfw rules, it is processed with IPSEC second time too. And it is encapsulated with ESP sencond time breaking PMTUD, again. I've found acceptable workaround: we need to say IPSEC code not to process already encapsulated packets: spdadd 1.1.1.1/32 2.2.2.2/32 esp -P out none; Sadly, setkey(8) parser has a bug preventing us from using this workaround. See http://www.freebsd.org/cgi/query-pr.cgi?pr=107392 for details and trivial patch against setkey. Eugene