From owner-freebsd-net@freebsd.org Fri Sep 25 13:42:58 2015 Return-Path: Delivered-To: freebsd-net@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 C902AA09872 for ; Fri, 25 Sep 2015 13:42:58 +0000 (UTC) (envelope-from rj@obsigna.com) Received: from mo6-p00-ob.smtp.rzone.de (mo6-p00-ob.smtp.rzone.de [IPv6:2a01:238:20a:202:5300::5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.smtp.rzone.de", Issuer "TeleSec ServerPass DE-2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 665CF1EF1 for ; Fri, 25 Sep 2015 13:42:57 +0000 (UTC) (envelope-from rj@obsigna.com) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1443188574; l=745; s=domk; d=obsigna.com; h=Mime-Version:To:Date:Subject:Content-Transfer-Encoding:Content-Type: From; bh=dXP9SKw0VLNTZVhcWWXyD85XEc83PgnwhqtwBArp16I=; b=OAp7tp6GmRYwLWciMoA0tmZIlgaOZY7HSFGCBL0DjoW682G4LjV0dYmeVGA4O2Dh25i C27ik8eRXMRygIjFGfrzr3MR3TcsKUGP0xV3oWv+yLH6lrMOLOm6fismWPGJnw5rHlp/k VLX6Fb4rZD7HtsXmF2DVtEvUs3O0zaombgI= X-RZG-AUTH: :O2kGeEG7b/pS1EK7WHa0hxqKZr4lnx6UhToX1IWHkW4X7v2ImaU2BqdKiuq0gOHBJBc= X-RZG-CLASS-ID: mo00 Received: from mail.obsigna.com (bb033d4b.virtua.com.br [187.3.61.75]) by smtp.strato.de (RZmta 37.12 DYNA|AUTH) with ESMTPSA id 903223r8PDgrchG (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (curve secp521r1 with 521 ECDH bits, eq. 15360 bits RSA)) (Client did not present a certificate) for ; Fri, 25 Sep 2015 15:42:53 +0200 (CEST) Received: from rolf.projectworld.net (rolf.projectworld.net [192.168.222.5]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.obsigna.com (Postfix) with ESMTPSA id 3DC9E14B90549 for ; Fri, 25 Sep 2015 10:42:50 -0300 (BRT) From: "Dr. Rolf Jansen" Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Clearance of checksum flags when decapsulating ESP packets Message-Id: Date: Fri, 25 Sep 2015 10:42:48 -0300 To: freebsd-net@freebsd.org Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2104\)) X-Mailer: Apple Mail (2.2104) X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Sep 2015 13:42:58 -0000 Please, may I ask about the rationale behind the lines 1557 to 1562 in = function udp4_espdecap() of file src/sys/netinet/udp_usrreq.c on = FreeBSD 10.2-RELEASE-p3. =E2=80=A6 /* * We cannot yet update the cksums so clear any * h/w cksum flags as they are no longer valid. */ if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) m->m_pkthdr.csum_flags &=3D = ~(CSUM_DATA_VALID|CSUM_PSEUDO_HDR); =E2=80=A6 I am specially interested in learning about possibly adverse effects on = operating an IPsec and IPsec-NAT-T enabled kernel when leaving the = checksum flags in place, i.e. removing the above lines from the file = src/sys/netinet/udp_usrreq.c. Many thanks in advance for any enlightment. Best regards Rolf Jansen