netfilter: bridge: move DNAT helper to br_netfilter

Only one caller, there is no need to keep this in a header.
Move it to br_netfilter.c where this belongs to.

Based on patch from Florian Westphal.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Pablo Neira Ayuso 2015-03-09 12:30:12 +01:00
parent 7a8d831df5
commit e5de75bf88
4 changed files with 38 additions and 16 deletions

View file

@ -44,18 +44,6 @@ static inline unsigned int nf_bridge_mtu_reduction(const struct sk_buff *skb)
}
int br_handle_frame_finish(struct sk_buff *skb);
/* Only used in br_device.c */
static inline int br_nf_pre_routing_finish_bridge_slow(struct sk_buff *skb)
{
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
skb_pull(skb, ETH_HLEN);
nf_bridge->mask ^= BRNF_BRIDGED_DNAT;
skb_copy_to_linear_data_offset(skb, -(ETH_HLEN-ETH_ALEN),
skb->nf_bridge->data, ETH_HLEN-ETH_ALEN);
skb->dev = nf_bridge->physindev;
return br_handle_frame_finish(skb);
}
/* This is called by the IP fragmenting code and it ensures there is
* enough room for the encapsulating header (if there is one). */

View file

@ -36,13 +36,10 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
u16 vid = 0;
rcu_read_lock();
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) {
br_nf_pre_routing_finish_bridge_slow(skb);
if (br_nf_prerouting_finish_bridge(skb)) {
rcu_read_unlock();
return NETDEV_TX_OK;
}
#endif
u64_stats_update_begin(&brstats->syncp);
brstats->tx_packets++;

View file

@ -892,6 +892,38 @@ static unsigned int ip_sabotage_in(const struct nf_hook_ops *ops,
return NF_ACCEPT;
}
/* This is called when br_netfilter has called into iptables/netfilter,
* and DNAT has taken place on a bridge-forwarded packet.
*
* neigh->output has created a new MAC header, with local br0 MAC
* as saddr.
*
* This restores the original MAC saddr of the bridged packet
* before invoking bridge forward logic to transmit the packet.
*/
static void br_nf_pre_routing_finish_bridge_slow(struct sk_buff *skb)
{
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
skb_pull(skb, ETH_HLEN);
nf_bridge->mask &= ~BRNF_BRIDGED_DNAT;
skb_copy_to_linear_data_offset(skb, -(ETH_HLEN-ETH_ALEN),
skb->nf_bridge->data, ETH_HLEN-ETH_ALEN);
skb->dev = nf_bridge->physindev;
br_handle_frame_finish(skb);
}
int br_nf_prerouting_finish_bridge(struct sk_buff *skb)
{
if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) {
br_nf_pre_routing_finish_bridge_slow(skb);
return 1;
}
return 0;
}
EXPORT_SYMBOL_GPL(br_nf_prerouting_finish_bridge);
void br_netfilter_enable(void)
{
}

View file

@ -764,10 +764,15 @@ static inline int br_vlan_enabled(struct net_bridge *br)
/* br_netfilter.c */
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
int br_nf_prerouting_finish_bridge(struct sk_buff *skb);
int br_nf_core_init(void);
void br_nf_core_fini(void);
void br_netfilter_rtable_init(struct net_bridge *);
#else
static inline int br_nf_prerouting_finish_bridge(struct sk_buff *skb)
{
return 0;
}
static inline int br_nf_core_init(void) { return 0; }
static inline void br_nf_core_fini(void) {}
#define br_netfilter_rtable_init(x)