linux/net/bridge/br_vlan.c
Vlad Yasevich 35e03f3a02 bridge: Separate egress policy bitmap
Add an ability to configure a separate "untagged" egress
policy to the VLAN information of the bridge.  This superseeds PVID
policy and makes PVID ingress-only.  The policy is configured with a
new flag and is represented as a port bitmap per vlan.  Egress frames
with a VLAN id in "untagged" policy bitmap would egress
the port without VLAN header.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-13 19:42:16 -05:00

416 lines
8.2 KiB
C

#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include "br_private.h"
static void __vlan_add_pvid(struct net_port_vlans *v, u16 vid)
{
if (v->pvid == vid)
return;
smp_wmb();
v->pvid = vid;
}
static void __vlan_delete_pvid(struct net_port_vlans *v, u16 vid)
{
if (v->pvid != vid)
return;
smp_wmb();
v->pvid = 0;
}
static void __vlan_add_flags(struct net_port_vlans *v, u16 vid, u16 flags)
{
if (flags & BRIDGE_VLAN_INFO_PVID)
__vlan_add_pvid(v, vid);
if (flags & BRIDGE_VLAN_INFO_UNTAGGED)
set_bit(vid, v->untagged_bitmap);
}
static int __vlan_add(struct net_port_vlans *v, u16 vid, u16 flags)
{
struct net_bridge_port *p = NULL;
struct net_bridge *br;
struct net_device *dev;
int err;
if (test_bit(vid, v->vlan_bitmap)) {
__vlan_add_flags(v, vid, flags);
return 0;
}
if (vid) {
if (v->port_idx) {
p = v->parent.port;
br = p->br;
dev = p->dev;
} else {
br = v->parent.br;
dev = br->dev;
}
if (p && (dev->features & NETIF_F_HW_VLAN_FILTER)) {
/* Add VLAN to the device filter if it is supported.
* Stricly speaking, this is not necessary now, since
* devices are made promiscuous by the bridge, but if
* that ever changes this code will allow tagged
* traffic to enter the bridge.
*/
err = dev->netdev_ops->ndo_vlan_rx_add_vid(dev, vid);
if (err)
return err;
}
err = br_fdb_insert(br, p, dev->dev_addr, vid);
if (err) {
br_err(br, "failed insert local address into bridge "
"forwarding table\n");
goto out_filt;
}
}
set_bit(vid, v->vlan_bitmap);
v->num_vlans++;
__vlan_add_flags(v, vid, flags);
return 0;
out_filt:
if (p && (dev->features & NETIF_F_HW_VLAN_FILTER))
dev->netdev_ops->ndo_vlan_rx_kill_vid(dev, vid);
return err;
}
static int __vlan_del(struct net_port_vlans *v, u16 vid)
{
if (!test_bit(vid, v->vlan_bitmap))
return -EINVAL;
__vlan_delete_pvid(v, vid);
clear_bit(vid, v->untagged_bitmap);
if (v->port_idx && vid) {
struct net_device *dev = v->parent.port->dev;
if (dev->features & NETIF_F_HW_VLAN_FILTER)
dev->netdev_ops->ndo_vlan_rx_kill_vid(dev, vid);
}
clear_bit(vid, v->vlan_bitmap);
v->num_vlans--;
if (bitmap_empty(v->vlan_bitmap, BR_VLAN_BITMAP_LEN)) {
if (v->port_idx)
rcu_assign_pointer(v->parent.port->vlan_info, NULL);
else
rcu_assign_pointer(v->parent.br->vlan_info, NULL);
kfree_rcu(v, rcu);
}
return 0;
}
static void __vlan_flush(struct net_port_vlans *v)
{
smp_wmb();
v->pvid = 0;
bitmap_zero(v->vlan_bitmap, BR_VLAN_BITMAP_LEN);
if (v->port_idx)
rcu_assign_pointer(v->parent.port->vlan_info, NULL);
else
rcu_assign_pointer(v->parent.br->vlan_info, NULL);
kfree_rcu(v, rcu);
}
/* Strip the tag from the packet. Will return skb with tci set 0. */
static struct sk_buff *br_vlan_untag(struct sk_buff *skb)
{
if (skb->protocol != htons(ETH_P_8021Q)) {
skb->vlan_tci = 0;
return skb;
}
skb->vlan_tci = 0;
skb = vlan_untag(skb);
if (skb)
skb->vlan_tci = 0;
return skb;
}
struct sk_buff *br_handle_vlan(struct net_bridge *br,
const struct net_port_vlans *pv,
struct sk_buff *skb)
{
u16 vid;
if (!br->vlan_enabled)
goto out;
/* At this point, we know that the frame was filtered and contains
* a valid vlan id. If the vlan id is set in the untagged bitmap,
* send untagged; otherwise, send taged.
*/
br_vlan_get_tag(skb, &vid);
if (test_bit(vid, pv->untagged_bitmap))
skb = br_vlan_untag(skb);
else {
/* Egress policy says "send tagged". If output device
* is the bridge, we need to add the VLAN header
* ourselves since we'll be going through the RX path.
* Sending to ports puts the frame on the TX path and
* we let dev_hard_start_xmit() add the header.
*/
if (skb->protocol != htons(ETH_P_8021Q) &&
pv->port_idx == 0) {
/* vlan_put_tag expects skb->data to point to
* mac header.
*/
skb_push(skb, ETH_HLEN);
skb = __vlan_put_tag(skb, skb->vlan_tci);
if (!skb)
goto out;
/* put skb->data back to where it was */
skb_pull(skb, ETH_HLEN);
skb->vlan_tci = 0;
}
}
out:
return skb;
}
/* Called under RCU */
bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v,
struct sk_buff *skb, u16 *vid)
{
/* If VLAN filtering is disabled on the bridge, all packets are
* permitted.
*/
if (!br->vlan_enabled)
return true;
/* If there are no vlan in the permitted list, all packets are
* rejected.
*/
if (!v)
return false;
if (br_vlan_get_tag(skb, vid)) {
u16 pvid = br_get_pvid(v);
/* Frame did not have a tag. See if pvid is set
* on this port. That tells us which vlan untagged
* traffic belongs to.
*/
if (pvid == VLAN_N_VID)
return false;
/* PVID is set on this port. Any untagged ingress
* frame is considered to belong to this vlan.
*/
__vlan_hwaccel_put_tag(skb, pvid);
return true;
}
/* Frame had a valid vlan tag. See if vlan is allowed */
if (test_bit(*vid, v->vlan_bitmap))
return true;
return false;
}
/* Called under RCU. */
bool br_allowed_egress(struct net_bridge *br,
const struct net_port_vlans *v,
const struct sk_buff *skb)
{
u16 vid;
if (!br->vlan_enabled)
return true;
if (!v)
return false;
br_vlan_get_tag(skb, &vid);
if (test_bit(vid, v->vlan_bitmap))
return true;
return false;
}
/* Must be protected by RTNL */
int br_vlan_add(struct net_bridge *br, u16 vid, u16 flags)
{
struct net_port_vlans *pv = NULL;
int err;
ASSERT_RTNL();
pv = rtnl_dereference(br->vlan_info);
if (pv)
return __vlan_add(pv, vid, flags);
/* Create port vlan infomration
*/
pv = kzalloc(sizeof(*pv), GFP_KERNEL);
if (!pv)
return -ENOMEM;
pv->parent.br = br;
err = __vlan_add(pv, vid, flags);
if (err)
goto out;
rcu_assign_pointer(br->vlan_info, pv);
return 0;
out:
kfree(pv);
return err;
}
/* Must be protected by RTNL */
int br_vlan_delete(struct net_bridge *br, u16 vid)
{
struct net_port_vlans *pv;
ASSERT_RTNL();
pv = rtnl_dereference(br->vlan_info);
if (!pv)
return -EINVAL;
if (vid) {
/* If the VID !=0 remove fdb for this vid. VID 0 is special
* in that it's the default and is always there in the fdb.
*/
spin_lock_bh(&br->hash_lock);
fdb_delete_by_addr(br, br->dev->dev_addr, vid);
spin_unlock_bh(&br->hash_lock);
}
__vlan_del(pv, vid);
return 0;
}
void br_vlan_flush(struct net_bridge *br)
{
struct net_port_vlans *pv;
ASSERT_RTNL();
pv = rtnl_dereference(br->vlan_info);
if (!pv)
return;
__vlan_flush(pv);
}
int br_vlan_filter_toggle(struct net_bridge *br, unsigned long val)
{
if (!rtnl_trylock())
return restart_syscall();
if (br->vlan_enabled == val)
goto unlock;
br->vlan_enabled = val;
unlock:
rtnl_unlock();
return 0;
}
/* Must be protected by RTNL */
int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags)
{
struct net_port_vlans *pv = NULL;
int err;
ASSERT_RTNL();
pv = rtnl_dereference(port->vlan_info);
if (pv)
return __vlan_add(pv, vid, flags);
/* Create port vlan infomration
*/
pv = kzalloc(sizeof(*pv), GFP_KERNEL);
if (!pv) {
err = -ENOMEM;
goto clean_up;
}
pv->port_idx = port->port_no;
pv->parent.port = port;
err = __vlan_add(pv, vid, flags);
if (err)
goto clean_up;
rcu_assign_pointer(port->vlan_info, pv);
return 0;
clean_up:
kfree(pv);
return err;
}
/* Must be protected by RTNL */
int nbp_vlan_delete(struct net_bridge_port *port, u16 vid)
{
struct net_port_vlans *pv;
ASSERT_RTNL();
pv = rtnl_dereference(port->vlan_info);
if (!pv)
return -EINVAL;
if (vid) {
/* If the VID !=0 remove fdb for this vid. VID 0 is special
* in that it's the default and is always there in the fdb.
*/
spin_lock_bh(&port->br->hash_lock);
fdb_delete_by_addr(port->br, port->dev->dev_addr, vid);
spin_unlock_bh(&port->br->hash_lock);
}
return __vlan_del(pv, vid);
}
void nbp_vlan_flush(struct net_bridge_port *port)
{
struct net_port_vlans *pv;
ASSERT_RTNL();
pv = rtnl_dereference(port->vlan_info);
if (!pv)
return;
__vlan_flush(pv);
}
bool nbp_vlan_find(struct net_bridge_port *port, u16 vid)
{
struct net_port_vlans *pv;
bool found = false;
rcu_read_lock();
pv = rcu_dereference(port->vlan_info);
if (!pv)
goto out;
if (test_bit(vid, pv->vlan_bitmap))
found = true;
out:
rcu_read_unlock();
return found;
}