netfilter: bridge: optionally set indev to vlan

if net.bridge.bridge-nf-filter-vlan-tagged sysctl is enabled, bridge
netfilter removes the vlan header temporarily and then feeds the packet
to ip(6)tables.

When the new "bridge-nf-pass-vlan-input-device" sysctl is on
(default off), then bridge netfilter will also set the
in-interface to the vlan interface; if such an interface exists.

This is needed to make iptables REDIRECT target work with
"vlan-on-top-of-bridge" setups and to allow use of "iptables -i" to
match the vlan device name.

Also update Documentation with current brnf default settings.

Signed-off-by: Florian Westphal <[email protected]>
Acked-by: Bart De Schuymer <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
This commit is contained in:
Pablo Neira Ayuso 2012-05-08 19:36:44 +02:00
commit 4981682cc1
2 changed files with 35 additions and 4 deletions

View file

@ -54,12 +54,14 @@ static int brnf_call_ip6tables __read_mostly = 1;
static int brnf_call_arptables __read_mostly = 1;
static int brnf_filter_vlan_tagged __read_mostly = 0;
static int brnf_filter_pppoe_tagged __read_mostly = 0;
static int brnf_pass_vlan_indev __read_mostly = 0;
#else
#define brnf_call_iptables 1
#define brnf_call_ip6tables 1
#define brnf_call_arptables 1
#define brnf_filter_vlan_tagged 0
#define brnf_filter_pppoe_tagged 0
#define brnf_pass_vlan_indev 0
#endif
#define IS_IP(skb) \
@ -503,6 +505,19 @@ bridged_dnat:
return 0;
}
static struct net_device *brnf_get_logical_dev(struct sk_buff *skb, const struct net_device *dev)
{
struct net_device *vlan, *br;
br = bridge_parent(dev);
if (brnf_pass_vlan_indev == 0 || !vlan_tx_tag_present(skb))
return br;
vlan = __vlan_find_dev_deep(br, vlan_tx_tag_get(skb) & VLAN_VID_MASK);
return vlan ? vlan : br;
}
/* Some common code for IPv4/IPv6 */
static struct net_device *setup_pre_routing(struct sk_buff *skb)
{
@ -515,7 +530,7 @@ static struct net_device *setup_pre_routing(struct sk_buff *skb)
nf_bridge->mask |= BRNF_NF_BRIDGE_PREROUTING;
nf_bridge->physindev = skb->dev;
skb->dev = bridge_parent(skb->dev);
skb->dev = brnf_get_logical_dev(skb, skb->dev);
if (skb->protocol == htons(ETH_P_8021Q))
nf_bridge->mask |= BRNF_8021Q;
else if (skb->protocol == htons(ETH_P_PPP_SES))
@ -774,7 +789,7 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff *skb,
else
skb->protocol = htons(ETH_P_IPV6);
NF_HOOK(pf, NF_INET_FORWARD, skb, bridge_parent(in), parent,
NF_HOOK(pf, NF_INET_FORWARD, skb, brnf_get_logical_dev(skb, in), parent,
br_nf_forward_finish);
return NF_STOLEN;
@ -1002,6 +1017,13 @@ static ctl_table brnf_table[] = {
.mode = 0644,
.proc_handler = brnf_sysctl_call_tables,
},
{
.procname = "bridge-nf-pass-vlan-input-dev",
.data = &brnf_pass_vlan_indev,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = brnf_sysctl_call_tables,
},
{ }
};
#endif