From patchwork Tue Mar 6 11:22:54 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 144916 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 962E8B6FA5 for ; Tue, 6 Mar 2012 22:23:18 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759117Ab2CFLXP (ORCPT ); Tue, 6 Mar 2012 06:23:15 -0500 Received: from mail.us.es ([193.147.175.20]:48358 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759096Ab2CFLXO (ORCPT ); Tue, 6 Mar 2012 06:23:14 -0500 Received: (qmail 7292 invoked from network); 6 Mar 2012 12:23:12 +0100 Received: from unknown (HELO us.es) (192.168.2.12) by us.es with SMTP; 6 Mar 2012 12:23:12 +0100 Received: (qmail 26262 invoked by uid 507); 6 Mar 2012 11:23:11 -0000 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on antivirus2 X-Spam-Level: X-Spam-Status: No, score=-99.2 required=7.5 tests=BAYES_50, USER_IN_WHITELIST autolearn=disabled version=3.3.1 Received: from 127.0.0.1 by antivirus2 (envelope-from , uid 501) with qmail-scanner-2.08 (clamdscan: 0.97.3/14593. 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Processed in 0.126712 secs); 06 Mar 2012 11:23:11 -0000 Received: from unknown (HELO antivirus2) (127.0.0.1) by us.es with SMTP; 6 Mar 2012 11:23:11 -0000 Received: from 192.168.1.13 (192.168.1.13) by antivirus2 (F-Secure/fsigk_smtp/407/antivirus2); Tue, 06 Mar 2012 12:23:11 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/407/antivirus2) Received: (qmail 14479 invoked from network); 6 Mar 2012 12:23:11 +0100 Received: from berligate.hmw-consulting.de (HELO soleta.de.gnumonks.org) (pneira@us.es@83.236.178.202) by us.es with SMTP; 6 Mar 2012 12:23:11 +0100 From: pablo@netfilter.org To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org Subject: [PATCH 5/6] bridge: netfilter: don't call iptables on vlan packets if sysctl is off Date: Tue, 6 Mar 2012 12:22:54 +0100 Message-Id: <1331032975-5303-6-git-send-email-pablo@netfilter.org> X-Mailer: git-send-email 1.7.7.3 In-Reply-To: <1331032975-5303-1-git-send-email-pablo@netfilter.org> References: <1331032975-5303-1-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: Florian Westphal When net.bridge.bridge-nf-filter-vlan-tagged is 0 (default), vlan packets arriving should not be sent to ip(6)tables by bridge netfilter. However, it turns out that we currently always send VLAN packets to netfilter, if .. a), CONFIG_VLAN_8021Q is enabled ; or b), CONFIG_VLAN_8021Q is not set but rx vlan offload is enabled on the bridge port. This is because bridge netfilter treats skb with skb->protocol == ETH_P_IP{V6} as "non-vlan packet". With rx vlan offload on or CONFIG_VLAN_8021Q=y, the vlan header has already been removed here, and we cannot rely on skb->protocol alone. Fix this by only using skb->protocol if the skb has no vlan tag, or if a vlan tag is present and filter-vlan-tagged bridge netfilter sysctl is enabled. We cannot remove the skb->protocol == htons(ETH_P_8021Q) test because the vlan tag is still around in the CONFIG_VLAN_8021Q=n && "ethtool -K $itf rxvlan off" case. reproducer: iptables -t raw -I PREROUTING -i br0 iptables -t raw -I PREROUTING -i br0.1 Then send packets to an ip address configured on br0.1 interface. Even with net.bridge.bridge-nf-filter-vlan-tagged=0, the 1st rule will match instead of the 2nd one. With this patch applied, the 2nd rule will match instead. In the non-local address case, netfilter won't be consulted after this patch unless the sysctl is switched on. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/bridge/br_netfilter.c | 32 ++++++++++++++++++-------------- 1 files changed, 18 insertions(+), 14 deletions(-) diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index 8412247..dec4f38 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -62,6 +62,15 @@ static int brnf_filter_pppoe_tagged __read_mostly = 0; #define brnf_filter_pppoe_tagged 0 #endif +#define IS_IP(skb) \ + (!vlan_tx_tag_present(skb) && skb->protocol == htons(ETH_P_IP)) + +#define IS_IPV6(skb) \ + (!vlan_tx_tag_present(skb) && skb->protocol == htons(ETH_P_IPV6)) + +#define IS_ARP(skb) \ + (!vlan_tx_tag_present(skb) && skb->protocol == htons(ETH_P_ARP)) + static inline __be16 vlan_proto(const struct sk_buff *skb) { if (vlan_tx_tag_present(skb)) @@ -639,8 +648,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff *skb, return NF_DROP; br = p->br; - if (skb->protocol == htons(ETH_P_IPV6) || IS_VLAN_IPV6(skb) || - IS_PPPOE_IPV6(skb)) { + if (IS_IPV6(skb) || IS_VLAN_IPV6(skb) || IS_PPPOE_IPV6(skb)) { if (!brnf_call_ip6tables && !br->nf_call_ip6tables) return NF_ACCEPT; @@ -651,8 +659,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff *skb, if (!brnf_call_iptables && !br->nf_call_iptables) return NF_ACCEPT; - if (skb->protocol != htons(ETH_P_IP) && !IS_VLAN_IP(skb) && - !IS_PPPOE_IP(skb)) + if (!IS_IP(skb) && !IS_VLAN_IP(skb) && !IS_PPPOE_IP(skb)) return NF_ACCEPT; nf_bridge_pull_encap_header_rcsum(skb); @@ -701,7 +708,7 @@ static int br_nf_forward_finish(struct sk_buff *skb) struct nf_bridge_info *nf_bridge = skb->nf_bridge; struct net_device *in; - if (skb->protocol != htons(ETH_P_ARP) && !IS_VLAN_ARP(skb)) { + if (!IS_ARP(skb) && !IS_VLAN_ARP(skb)) { in = nf_bridge->physindev; if (nf_bridge->mask & BRNF_PKT_TYPE) { skb->pkt_type = PACKET_OTHERHOST; @@ -718,6 +725,7 @@ static int br_nf_forward_finish(struct sk_buff *skb) return 0; } + /* This is the 'purely bridged' case. For IP, we pass the packet to * netfilter with indev and outdev set to the bridge device, * but we are still able to filter on the 'real' indev/outdev @@ -744,11 +752,9 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff *skb, if (!parent) return NF_DROP; - if (skb->protocol == htons(ETH_P_IP) || IS_VLAN_IP(skb) || - IS_PPPOE_IP(skb)) + if (IS_IP(skb) || IS_VLAN_IP(skb) || IS_PPPOE_IP(skb)) pf = PF_INET; - else if (skb->protocol == htons(ETH_P_IPV6) || IS_VLAN_IPV6(skb) || - IS_PPPOE_IPV6(skb)) + else if (IS_IPV6(skb) || IS_VLAN_IPV6(skb) || IS_PPPOE_IPV6(skb)) pf = PF_INET6; else return NF_ACCEPT; @@ -795,7 +801,7 @@ static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff *skb, if (!brnf_call_arptables && !br->nf_call_arptables) return NF_ACCEPT; - if (skb->protocol != htons(ETH_P_ARP)) { + if (!IS_ARP(skb)) { if (!IS_VLAN_ARP(skb)) return NF_ACCEPT; nf_bridge_pull_encap_header(skb); @@ -853,11 +859,9 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff *skb, if (!realoutdev) return NF_DROP; - if (skb->protocol == htons(ETH_P_IP) || IS_VLAN_IP(skb) || - IS_PPPOE_IP(skb)) + if (IS_IP(skb) || IS_VLAN_IP(skb) || IS_PPPOE_IP(skb)) pf = PF_INET; - else if (skb->protocol == htons(ETH_P_IPV6) || IS_VLAN_IPV6(skb) || - IS_PPPOE_IPV6(skb)) + else if (IS_IPV6(skb) || IS_VLAN_IPV6(skb) || IS_PPPOE_IPV6(skb)) pf = PF_INET6; else return NF_ACCEPT;