From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: [PATCH 11/18] netfilter: Allow calling into nat helper without skb_dst. Date: Tue, 15 Mar 2016 02:27:55 +0100 Message-ID: <1458005282-24665-12-git-send-email-pablo@netfilter.org> References: <1458005282-24665-1-git-send-email-pablo@netfilter.org> Cc: davem@davemloft.net, netdev@vger.kernel.org To: netfilter-devel@vger.kernel.org Return-path: Received: from mail.us.es ([193.147.175.20]:33242 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933354AbcCOB2c (ORCPT ); Mon, 14 Mar 2016 21:28:32 -0400 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 704A0114F4E for ; Tue, 15 Mar 2016 02:28:30 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 61B80DA38A for ; Tue, 15 Mar 2016 02:28:30 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 56291DA391 for ; Tue, 15 Mar 2016 02:28:28 +0100 (CET) In-Reply-To: <1458005282-24665-1-git-send-email-pablo@netfilter.org> Sender: netfilter-devel-owner@vger.kernel.org List-ID: From: Jarno Rajahalme NAT checksum recalculation code assumes existence of skb_dst, which becomes a problem for a later patch in the series ("openvswitch: Interface with NAT."). Simplify this by removing the check on skb_dst, as the checksum will be dealt with later in the stack. Suggested-by: Pravin Shelar Signed-off-by: Jarno Rajahalme Signed-off-by: Pablo Neira Ayuso --- net/ipv4/netfilter/nf_nat_l3proto_ipv4.c | 30 ++++++++---------------------- net/ipv6/netfilter/nf_nat_l3proto_ipv6.c | 30 ++++++++---------------------- 2 files changed, 16 insertions(+), 44 deletions(-) diff --git a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c index 61c7cc2..f8aad03 100644 --- a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c +++ b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c @@ -127,29 +127,15 @@ static void nf_nat_ipv4_csum_recalc(struct sk_buff *skb, u8 proto, void *data, __sum16 *check, int datalen, int oldlen) { - const struct iphdr *iph = ip_hdr(skb); - struct rtable *rt = skb_rtable(skb); - if (skb->ip_summed != CHECKSUM_PARTIAL) { - if (!(rt->rt_flags & RTCF_LOCAL) && - (!skb->dev || skb->dev->features & - (NETIF_F_IP_CSUM | NETIF_F_HW_CSUM))) { - skb->ip_summed = CHECKSUM_PARTIAL; - skb->csum_start = skb_headroom(skb) + - skb_network_offset(skb) + - ip_hdrlen(skb); - skb->csum_offset = (void *)check - data; - *check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, - datalen, proto, 0); - } else { - *check = 0; - *check = csum_tcpudp_magic(iph->saddr, iph->daddr, - datalen, proto, - csum_partial(data, datalen, - 0)); - if (proto == IPPROTO_UDP && !*check) - *check = CSUM_MANGLED_0; - } + const struct iphdr *iph = ip_hdr(skb); + + skb->ip_summed = CHECKSUM_PARTIAL; + skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) + + ip_hdrlen(skb); + skb->csum_offset = (void *)check - data; + *check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, datalen, + proto, 0); } else inet_proto_csum_replace2(check, skb, htons(oldlen), htons(datalen), true); diff --git a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c index 6ce3099..e0be97e 100644 --- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c +++ b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c @@ -131,29 +131,15 @@ static void nf_nat_ipv6_csum_recalc(struct sk_buff *skb, u8 proto, void *data, __sum16 *check, int datalen, int oldlen) { - const struct ipv6hdr *ipv6h = ipv6_hdr(skb); - struct rt6_info *rt = (struct rt6_info *)skb_dst(skb); - if (skb->ip_summed != CHECKSUM_PARTIAL) { - if (!(rt->rt6i_flags & RTF_LOCAL) && - (!skb->dev || skb->dev->features & - (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM))) { - skb->ip_summed = CHECKSUM_PARTIAL; - skb->csum_start = skb_headroom(skb) + - skb_network_offset(skb) + - (data - (void *)skb->data); - skb->csum_offset = (void *)check - data; - *check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, - datalen, proto, 0); - } else { - *check = 0; - *check = csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, - datalen, proto, - csum_partial(data, datalen, - 0)); - if (proto == IPPROTO_UDP && !*check) - *check = CSUM_MANGLED_0; - } + const struct ipv6hdr *ipv6h = ipv6_hdr(skb); + + skb->ip_summed = CHECKSUM_PARTIAL; + skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) + + (data - (void *)skb->data); + skb->csum_offset = (void *)check - data; + *check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, + datalen, proto, 0); } else inet_proto_csum_replace2(check, skb, htons(oldlen), htons(datalen), true); -- 2.1.4