linux/net/bridge/br_vlan.c
Vlad Yasevich 3df6bf45ec bridge: Simplify pvid checks.
Currently, if the pvid is not set, we return an illegal vlan value
even though the pvid value is set to 0.  Since pvid of 0 is currently
invalid, just return 0 instead.  This makes the current and future
checks simpler.

Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-05 21:21:36 -04:00

625 lines
12 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);
else
__vlan_delete_pvid(v, vid);
if (flags & BRIDGE_VLAN_INFO_UNTAGGED)
set_bit(vid, v->untagged_bitmap);
else
clear_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 (v->port_idx) {
p = v->parent.port;
br = p->br;
dev = p->dev;
} else {
br = v->parent.br;
dev = br->dev;
}
if (p) {
/* Add VLAN to the device filter if it is supported.
* This ensures tagged traffic enters the bridge when
* promiscuous mode is disabled by br_manage_promisc().
*/
err = vlan_vid_add(dev, br->vlan_proto, 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)
vlan_vid_del(dev, br->vlan_proto, 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) {
struct net_bridge_port *p = v->parent.port;
vlan_vid_del(p->dev, p->br->vlan_proto, vid);
}
clear_bit(vid, v->vlan_bitmap);
v->num_vlans--;
if (bitmap_empty(v->vlan_bitmap, VLAN_N_VID)) {
if (v->port_idx)
RCU_INIT_POINTER(v->parent.port->vlan_info, NULL);
else
RCU_INIT_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, VLAN_N_VID);
if (v->port_idx)
RCU_INIT_POINTER(v->parent.port->vlan_info, NULL);
else
RCU_INIT_POINTER(v->parent.br->vlan_info, NULL);
kfree_rcu(v, rcu);
}
struct sk_buff *br_handle_vlan(struct net_bridge *br,
const struct net_port_vlans *pv,
struct sk_buff *skb)
{
u16 vid;
/* If this packet was not filtered at input, let it pass */
if (!BR_INPUT_SKB_CB(skb)->vlan_filtered)
goto out;
/* Vlan filter table must be configured at this point. The
* only exception is the bridge is set in promisc mode and the
* packet is destined for the bridge device. In this case
* pass the packet as is.
*/
if (!pv) {
if ((br->dev->flags & IFF_PROMISC) && skb->dev == br->dev) {
goto out;
} else {
kfree_skb(skb);
return NULL;
}
}
/* 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 tagged.
*/
br_vlan_get_tag(skb, &vid);
if (test_bit(vid, pv->untagged_bitmap))
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)
{
bool tagged;
__be16 proto;
/* If VLAN filtering is disabled on the bridge, all packets are
* permitted.
*/
if (!br->vlan_enabled) {
BR_INPUT_SKB_CB(skb)->vlan_filtered = false;
return true;
}
/* If there are no vlan in the permitted list, all packets are
* rejected.
*/
if (!v)
goto drop;
BR_INPUT_SKB_CB(skb)->vlan_filtered = true;
proto = br->vlan_proto;
/* If vlan tx offload is disabled on bridge device and frame was
* sent from vlan device on the bridge device, it does not have
* HW accelerated vlan tag.
*/
if (unlikely(!vlan_tx_tag_present(skb) &&
skb->protocol == proto)) {
skb = skb_vlan_untag(skb);
if (unlikely(!skb))
return false;
}
if (!br_vlan_get_tag(skb, vid)) {
/* Tagged frame */
if (skb->vlan_proto != proto) {
/* Protocol-mismatch, empty out vlan_tci for new tag */
skb_push(skb, ETH_HLEN);
skb = __vlan_put_tag(skb, skb->vlan_proto,
vlan_tx_tag_get(skb));
if (unlikely(!skb))
return false;
skb_pull(skb, ETH_HLEN);
skb_reset_mac_len(skb);
*vid = 0;
tagged = false;
} else {
tagged = true;
}
} else {
/* Untagged frame */
tagged = false;
}
if (!*vid) {
u16 pvid = br_get_pvid(v);
/* Frame had a tag with VID 0 or did not have a tag.
* See if pvid is set on this port. That tells us which
* vlan untagged or priority-tagged traffic belongs to.
*/
if (!pvid)
goto drop;
/* PVID is set on this port. Any untagged or priority-tagged
* ingress frame is considered to belong to this vlan.
*/
*vid = pvid;
if (likely(!tagged))
/* Untagged Frame. */
__vlan_hwaccel_put_tag(skb, proto, pvid);
else
/* Priority-tagged Frame.
* At this point, We know that skb->vlan_tci had
* VLAN_TAG_PRESENT bit and its VID field was 0x000.
* We update only VID field and preserve PCP field.
*/
skb->vlan_tci |= pvid;
return true;
}
/* Frame had a valid vlan tag. See if vlan is allowed */
if (test_bit(*vid, v->vlan_bitmap))
return true;
drop:
kfree_skb(skb);
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 this packet was not filtered at input, let it pass */
if (!BR_INPUT_SKB_CB(skb)->vlan_filtered)
return true;
if (!v)
return false;
br_vlan_get_tag(skb, &vid);
if (test_bit(vid, v->vlan_bitmap))
return true;
return false;
}
/* Called under RCU */
bool br_should_learn(struct net_bridge_port *p, struct sk_buff *skb, u16 *vid)
{
struct net_bridge *br = p->br;
struct net_port_vlans *v;
/* If filtering was disabled at input, let it pass. */
if (!br->vlan_enabled)
return true;
v = rcu_dereference(p->vlan_info);
if (!v)
return false;
if (!br_vlan_get_tag(skb, vid) && skb->vlan_proto != br->vlan_proto)
*vid = 0;
if (!*vid) {
*vid = br_get_pvid(v);
if (!*vid)
return false;
return true;
}
if (test_bit(*vid, v->vlan_bitmap))
return true;
return false;
}
/* Must be protected by RTNL.
* Must be called with vid in range from 1 to 4094 inclusive.
*/
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.
* Must be called with vid in range from 1 to 4094 inclusive.
*/
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;
br_fdb_find_delete_local(br, NULL, br->dev->dev_addr, vid);
__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);
}
bool br_vlan_find(struct net_bridge *br, u16 vid)
{
struct net_port_vlans *pv;
bool found = false;
rcu_read_lock();
pv = rcu_dereference(br->vlan_info);
if (!pv)
goto out;
if (test_bit(vid, pv->vlan_bitmap))
found = true;
out:
rcu_read_unlock();
return found;
}
/* Must be protected by RTNL. */
static void recalculate_group_addr(struct net_bridge *br)
{
if (br->group_addr_set)
return;
spin_lock_bh(&br->lock);
if (!br->vlan_enabled || br->vlan_proto == htons(ETH_P_8021Q)) {
/* Bridge Group Address */
br->group_addr[5] = 0x00;
} else { /* vlan_enabled && ETH_P_8021AD */
/* Provider Bridge Group Address */
br->group_addr[5] = 0x08;
}
spin_unlock_bh(&br->lock);
}
/* Must be protected by RTNL. */
void br_recalculate_fwd_mask(struct net_bridge *br)
{
if (!br->vlan_enabled || br->vlan_proto == htons(ETH_P_8021Q))
br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT;
else /* vlan_enabled && ETH_P_8021AD */
br->group_fwd_mask_required = BR_GROUPFWD_8021AD &
~(1u << br->group_addr[5]);
}
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;
br_manage_promisc(br);
recalculate_group_addr(br);
br_recalculate_fwd_mask(br);
unlock:
rtnl_unlock();
return 0;
}
int br_vlan_set_proto(struct net_bridge *br, unsigned long val)
{
int err = 0;
struct net_bridge_port *p;
struct net_port_vlans *pv;
__be16 proto, oldproto;
u16 vid, errvid;
if (val != ETH_P_8021Q && val != ETH_P_8021AD)
return -EPROTONOSUPPORT;
if (!rtnl_trylock())
return restart_syscall();
proto = htons(val);
if (br->vlan_proto == proto)
goto unlock;
/* Add VLANs for the new proto to the device filter. */
list_for_each_entry(p, &br->port_list, list) {
pv = rtnl_dereference(p->vlan_info);
if (!pv)
continue;
for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) {
err = vlan_vid_add(p->dev, proto, vid);
if (err)
goto err_filt;
}
}
oldproto = br->vlan_proto;
br->vlan_proto = proto;
recalculate_group_addr(br);
br_recalculate_fwd_mask(br);
/* Delete VLANs for the old proto from the device filter. */
list_for_each_entry(p, &br->port_list, list) {
pv = rtnl_dereference(p->vlan_info);
if (!pv)
continue;
for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID)
vlan_vid_del(p->dev, oldproto, vid);
}
unlock:
rtnl_unlock();
return err;
err_filt:
errvid = vid;
for_each_set_bit(vid, pv->vlan_bitmap, errvid)
vlan_vid_del(p->dev, proto, vid);
list_for_each_entry_continue_reverse(p, &br->port_list, list) {
pv = rtnl_dereference(p->vlan_info);
if (!pv)
continue;
for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID)
vlan_vid_del(p->dev, proto, vid);
}
goto unlock;
}
int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val)
{
u16 pvid = val;
int err = 0;
if (!val || val >= VLAN_VID_MASK)
return -EINVAL;
if (!rtnl_trylock())
return restart_syscall();
if (pvid == br->default_pvid)
goto unlock;
/* Only allow default pvid change when filtering is disabled */
if (br->vlan_enabled) {
pr_info_once("Please disable vlan filtering to change default_pvid\n");
err = -EPERM;
goto unlock;
}
br->default_pvid = pvid;
unlock:
rtnl_unlock();
return err;
}
void br_vlan_init(struct net_bridge *br)
{
br->vlan_proto = htons(ETH_P_8021Q);
br->default_pvid = 1;
}
/* Must be protected by RTNL.
* Must be called with vid in range from 1 to 4094 inclusive.
*/
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.
* Must be called with vid in range from 1 to 4094 inclusive.
*/
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;
br_fdb_find_delete_local(port->br, port, port->dev->dev_addr, vid);
return __vlan_del(pv, vid);
}
void nbp_vlan_flush(struct net_bridge_port *port)
{
struct net_port_vlans *pv;
u16 vid;
ASSERT_RTNL();
pv = rtnl_dereference(port->vlan_info);
if (!pv)
return;
for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID)
vlan_vid_del(port->dev, port->br->vlan_proto, vid);
__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;
}