From e5de75bf88858f5b3ab11e2504b86ec059f03102 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 9 Mar 2015 12:30:12 +0100 Subject: 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 --- net/bridge/br_device.c | 5 +---- net/bridge/br_netfilter.c | 32 ++++++++++++++++++++++++++++++++ net/bridge/br_private.h | 5 +++++ 3 files changed, 38 insertions(+), 4 deletions(-) (limited to 'net/bridge') diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c index ffd379db5938..294cbcc49263 100644 --- a/net/bridge/br_device.c +++ b/net/bridge/br_device.c @@ -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++; diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index ef1fe281ca11..a8361c7cdf81 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -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) { } diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index de0919975a25..d63fc17fe4f4 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -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) -- cgit v1.2.3