From patchwork Mon Nov 4 21:50:35 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 288268 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id E1B0E2C00BE for ; Tue, 5 Nov 2013 08:51:21 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753850Ab3KDVvL (ORCPT ); Mon, 4 Nov 2013 16:51:11 -0500 Received: from mail.us.es ([193.147.175.20]:55762 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752195Ab3KDVvK (ORCPT ); Mon, 4 Nov 2013 16:51:10 -0500 Received: (qmail 1930 invoked from network); 4 Nov 2013 22:51:08 +0100 Received: from unknown (HELO us.es) (192.168.2.15) by us.es with SMTP; 4 Nov 2013 22:51:08 +0100 Received: (qmail 643 invoked by uid 507); 4 Nov 2013 21:51:08 -0000 X-Qmail-Scanner-Diagnostics: from 127.0.0.1 by antivirus5 (envelope-from , uid 501) with qmail-scanner-2.10 (clamdscan: 0.98/18064. spamassassin: 3.3.2. Clear:RC:1(127.0.0.1):SA:0(-97.2/7.5):. Processed in 11.840129 secs); 04 Nov 2013 21:51:08 -0000 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on antivirus5 X-Spam-Level: X-Spam-Status: No, score=-97.2 required=7.5 tests=BAYES_50,RCVD_IN_BRBL, RCVD_IN_BRBL_LASTEXT, RCVD_IN_PBL, RCVD_IN_SORBS_DUL, RCVD_IN_XBL, RDNS_DYNAMIC, SMTPAUTH_US,USER_IN_WHITELIST autolearn=disabled version=3.3.2 X-Spam-ASN: AS12715 188.78.0.0/16 X-Envelope-From: pablo@netfilter.org Received: from unknown (HELO antivirus5) (127.0.0.1) by us.es with SMTP; 4 Nov 2013 21:50:57 -0000 Received: from 192.168.1.13 (192.168.1.13) by antivirus5 (F-Secure/fsigk_smtp/412/antivirus5); Mon, 04 Nov 2013 22:50:57 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/412/antivirus5) Received: (qmail 3932 invoked from network); 4 Nov 2013 22:50:56 +0100 Received: from 215.82.78.188.dynamic.jazztel.es (HELO localhost.localdomain) (pneira@us.es@188.78.82.215) by mail.us.es with SMTP; 4 Nov 2013 22:50:56 +0100 From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org Subject: [PATCH 13/20] netfilter: ip6t_REJECT: skip checksum verification for outgoing ipv6 packets Date: Mon, 4 Nov 2013 22:50:35 +0100 Message-Id: <1383601842-4570-14-git-send-email-pablo@netfilter.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1383601842-4570-1-git-send-email-pablo@netfilter.org> References: <1383601842-4570-1-git-send-email-pablo@netfilter.org> Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org From: Stanislav Fomichev Don't verify checksum for outgoing packets because checksum calculation may be done by the device. Without this patch: $ ip6tables -I OUTPUT -p tcp --dport 80 -j REJECT --reject-with tcp-reset $ time telnet ipv6.google.com 80 Trying 2a00:1450:4010:c03::67... telnet: Unable to connect to remote host: Connection timed out real 0m7.201s user 0m0.000s sys 0m0.000s With the patch applied: $ ip6tables -I OUTPUT -p tcp --dport 80 -j REJECT --reject-with tcp-reset $ time telnet ipv6.google.com 80 Trying 2a00:1450:4010:c03::67... telnet: Unable to connect to remote host: Connection refused real 0m0.085s user 0m0.000s sys 0m0.000s Signed-off-by: Stanislav Fomichev Signed-off-by: Pablo Neira Ayuso --- net/ipv6/netfilter/ip6t_REJECT.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/net/ipv6/netfilter/ip6t_REJECT.c b/net/ipv6/netfilter/ip6t_REJECT.c index 56eef30..da00a2e 100644 --- a/net/ipv6/netfilter/ip6t_REJECT.c +++ b/net/ipv6/netfilter/ip6t_REJECT.c @@ -39,7 +39,7 @@ MODULE_DESCRIPTION("Xtables: packet \"rejection\" target for IPv6"); MODULE_LICENSE("GPL"); /* Send RST reply */ -static void send_reset(struct net *net, struct sk_buff *oldskb) +static void send_reset(struct net *net, struct sk_buff *oldskb, int hook) { struct sk_buff *nskb; struct tcphdr otcph, *tcph; @@ -88,8 +88,7 @@ static void send_reset(struct net *net, struct sk_buff *oldskb) } /* Check checksum. */ - if (csum_ipv6_magic(&oip6h->saddr, &oip6h->daddr, otcplen, IPPROTO_TCP, - skb_checksum(oldskb, tcphoff, otcplen, 0))) { + if (nf_ip6_checksum(oldskb, hook, tcphoff, IPPROTO_TCP)) { pr_debug("TCP checksum is invalid\n"); return; } @@ -227,7 +226,7 @@ reject_tg6(struct sk_buff *skb, const struct xt_action_param *par) /* Do nothing */ break; case IP6T_TCP_RESET: - send_reset(net, skb); + send_reset(net, skb, par->hooknum); break; default: net_info_ratelimited("case %u not handled yet\n", reject->with);