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 change the in/out
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. Also, 'iptables -i' can then be used
to match the vlan device name.
Also update Documentation with current brnf default settings.
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
Documentation/networking/ip-sysctl.txt | 13 +++++++++-
net/bridge/br_netfilter.c | 39 +++++++++++++++++++++++++------
2 files changed, 42 insertions(+), 10 deletions(-)
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index ad3e80e..ee0374a 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -1294,13 +1294,22 @@ bridge-nf-call-ip6tables - BOOLEAN
bridge-nf-filter-vlan-tagged - BOOLEAN
1 : pass bridged vlan-tagged ARP/IP/IPv6 traffic to {arp,ip,ip6}tables.
0 : disable this.
- Default: 1
+ Default: 0
bridge-nf-filter-pppoe-tagged - BOOLEAN
1 : pass bridged pppoe-tagged IP/IPv6 traffic to {ip,ip6}tables.
0 : disable this.
- Default: 1
+ Default: 0
+bridge-nf-pass-vlan-input-dev - BOOLEAN
+ 1: if bridge-nf-filter-vlan-tagged is enabled, try to find a vlan
+ interface on the bridge and set the netfilter input device to the vlan.
+ This allows use of e.g. "iptables -i br0.1" and makes the REDIRECT
+ target work with vlan-on-top-of-bridge interfaces. When no matching
+ vlan interface is found, or this switch is off, the input device is
+ set to the bridge interface.
+ 0: disable bridge netfilter vlan interface lookup.
+ Default: 0
proc/sys/net/sctp/* Variables:
diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index dec4f38..1d69feb 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -53,6 +53,7 @@ static int brnf_call_iptables __read_mostly = 1;
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_pass_vlan_indev __read_mostly = 0;
static int brnf_filter_pppoe_tagged __read_mostly = 0;
#else
#define brnf_call_iptables 1
@@ -503,6 +504,19 @@ 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 +529,7 @@ 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))
@@ -737,7 +751,7 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff *skb,
int (*okfn)(struct sk_buff *))
{
struct nf_bridge_info *nf_bridge;
- struct net_device *parent;
+ struct net_device *parent, *indev;
u_int8_t pf;
if (!skb->nf_bridge)
@@ -748,10 +762,6 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff *skb,
if (!nf_bridge_unshare(skb))
return NF_DROP;
- parent = bridge_parent(out);
- if (!parent)
- return NF_DROP;
-
if (IS_IP(skb) || IS_VLAN_IP(skb) || IS_PPPOE_IP(skb))
pf = PF_INET;
else if (IS_IPV6(skb) || IS_VLAN_IPV6(skb) || IS_PPPOE_IPV6(skb))
@@ -759,6 +769,10 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff *skb,
else
return NF_ACCEPT;
+ parent = brnf_get_logical_dev(skb, out);
+ if (!parent)
+ return NF_DROP;
+
nf_bridge_pull_encap_header(skb);
nf_bridge = skb->nf_bridge;
@@ -778,7 +792,9 @@ 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,
+ indev = brnf_get_logical_dev(skb, in);
+
+ NF_HOOK(pf, NF_INET_FORWARD, skb, indev, parent,
br_nf_forward_finish);
return NF_STOLEN;
@@ -850,7 +866,7 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff *skb,
int (*okfn)(struct sk_buff *))
{
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
- struct net_device *realoutdev = bridge_parent(skb->dev);
+ struct net_device *realoutdev = brnf_get_logical_dev(skb, out);
u_int8_t pf;
if (!nf_bridge || !(nf_bridge->mask & BRNF_BRIDGED))
@@ -1006,6 +1022,13 @@ 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,
+ },
{ }
};
--
1.7.3.4
--
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