netfilter: bridge: query conntrack about skb dnat

ask conntrack instead of storing ipv4 address in nf_bridge_info->data.

Ths avoids the need to use ->data during NF_PRE_ROUTING.
Only two functions that need ->data remain.

These will be addressed in followup patches.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2015-03-10 05:08:19 +01:00 committed by Pablo Neira Ayuso
parent 169bf9121b
commit c055d5b03b
2 changed files with 21 additions and 12 deletions

View File

@ -54,12 +54,6 @@ static inline unsigned int nf_bridge_pad(const struct sk_buff *skb)
return 0;
}
struct bridge_skb_cb {
union {
__be32 ipv4;
} daddr;
};
static inline void br_drop_fake_rtable(struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);

View File

@ -37,17 +37,16 @@
#include <net/route.h>
#include <net/netfilter/br_netfilter.h>
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
#include <net/netfilter/nf_conntrack.h>
#endif
#include <asm/uaccess.h>
#include "br_private.h"
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif
#define skb_origaddr(skb) (((struct bridge_skb_cb *) \
(skb->nf_bridge->data))->daddr.ipv4)
#define store_orig_dstaddr(skb) (skb_origaddr(skb) = ip_hdr(skb)->daddr)
#define dnat_took_place(skb) (skb_origaddr(skb) != ip_hdr(skb)->daddr)
#ifdef CONFIG_SYSCTL
static struct ctl_table_header *brnf_sysctl_header;
static int brnf_call_iptables __read_mostly = 1;
@ -322,6 +321,22 @@ static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
return 0;
}
static bool dnat_took_place(const struct sk_buff *skb)
{
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
enum ip_conntrack_info ctinfo;
struct nf_conn *ct;
ct = nf_ct_get(skb, &ctinfo);
if (!ct || nf_ct_is_untracked(ct))
return false;
return test_bit(IPS_DST_NAT_BIT, &ct->status);
#else
return false;
#endif
}
/* This requires some explaining. If DNAT has taken place,
* we will need to fix up the destination Ethernet address.
*
@ -625,7 +640,7 @@ static unsigned int br_nf_pre_routing(const struct nf_hook_ops *ops,
return NF_DROP;
if (!setup_pre_routing(skb))
return NF_DROP;
store_orig_dstaddr(skb);
skb->protocol = htons(ETH_P_IP);
NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, skb->dev, NULL,