/**
* mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
*
* @skb: 802.11 frame to be sent
* @sdata: network subif the frame will be sent through
*
* Lookup next hop for given skb and start path discovery if no
* forwarding information is found.
*
* Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
* skb is freeed here if no mpath could be allocated.
*/
int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct mesh_path *mpath;
struct sk_buff *skb_to_free = NULL;
u8 *target_addr = hdr->addr3;
int err = 0;
/* Nulls are only sent to peers for PS and should be pre-addressed */
if (ieee80211_is_qos_nullfunc(hdr->frame_control))
return 0;
rcu_read_lock();
err = mesh_nexthop_lookup(sdata, skb);
if (!err)
goto endlookup;
/* no nexthop found, start resolving */
mpath = mesh_path_lookup(sdata, target_addr);
if (!mpath) {
mesh_path_add(sdata, target_addr);
mpath = mesh_path_lookup(sdata, target_addr);
if (!mpath) {
mesh_path_discard_frame(sdata, skb);
err = -ENOSPC;
goto endlookup;
}
}
if (!(mpath->flags & MESH_PATH_RESOLVING))
mesh_queue_preq(mpath, PREQ_Q_F_START);
if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
skb_to_free = skb_dequeue(&mpath->frame_queue);
info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
ieee80211_set_qos_hdr(sdata, skb);
skb_queue_tail(&mpath->frame_queue, skb);
err = -ENOENT;
if (skb_to_free)
mesh_path_discard_frame(sdata, skb_to_free);
endlookup:
rcu_read_unlock();
return err;
}
/**
* mesh_nexthop_lookup - put the appropriate next hop on a mesh frame
*
* @skb: 802.11 frame to be sent
* @sdata: network subif the frame will be sent through
*
* Returns: 0 if the next hop was found. Nonzero otherwise. If no next hop is
* found, the function will start a path discovery and queue the frame so it is
* sent when the path is resolved. This means the caller must not free the skb
* in this case.
*/
int mesh_nexthop_lookup(struct sk_buff *skb,
struct ieee80211_sub_if_data *sdata)
{
struct sk_buff *skb_to_free = NULL;
struct mesh_path *mpath;
struct sta_info *next_hop;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
u8 *target_addr = hdr->addr3;
int err = 0;
rcu_read_lock();
mpath = mesh_path_lookup(target_addr, sdata);
if (!mpath) {
mesh_path_add(target_addr, sdata);
mpath = mesh_path_lookup(target_addr, sdata);
if (!mpath) {
sdata->u.mesh.mshstats.dropped_frames_no_route++;
err = -ENOSPC;
goto endlookup;
}
}
if (mpath->flags & MESH_PATH_ACTIVE) {
if (time_after(jiffies,
mpath->exp_time -
msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
!memcmp(sdata->vif.addr, hdr->addr4, ETH_ALEN) &&
!(mpath->flags & MESH_PATH_RESOLVING) &&
!(mpath->flags & MESH_PATH_FIXED)) {
mesh_queue_preq(mpath,
PREQ_Q_F_START | PREQ_Q_F_REFRESH);
}
next_hop = rcu_dereference(mpath->next_hop);
if (next_hop)
memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
else
err = -ENOENT;
} else {
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
if (!(mpath->flags & MESH_PATH_RESOLVING)) {
/* Start discovery only if it is not running yet */
mesh_queue_preq(mpath, PREQ_Q_F_START);
}
if (skb_queue_len(&mpath->frame_queue) >=
MESH_FRAME_QUEUE_LEN)
skb_to_free = skb_dequeue(&mpath->frame_queue);
info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
skb_queue_tail(&mpath->frame_queue, skb);
if (skb_to_free)
mesh_path_discard_frame(skb_to_free, sdata);
err = -ENOENT;
}
endlookup:
rcu_read_unlock();
return err;
}
/**
* ieee80211s_lookup_nexthop - put the appropriate next hop on a mesh frame
*
* @next_hop: output argument for next hop address
* @skb: frame to be sent
* @dev: network device the frame will be sent through
*
* Returns: 0 if the next hop was found. Nonzero otherwise. If no next hop is
* found, the function will start a path discovery and queue the frame so it is
* sent when the path is resolved. This means the caller must not free the skb
* in this case.
*/
int mesh_nexthop_lookup(u8 *next_hop, struct sk_buff *skb,
struct net_device *dev)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct sk_buff *skb_to_free = NULL;
struct mesh_path *mpath;
int err = 0;
rcu_read_lock();
mpath = mesh_path_lookup(skb->data, dev);
if (!mpath) {
mesh_path_add(skb->data, dev);
mpath = mesh_path_lookup(skb->data, dev);
if (!mpath) {
dev_kfree_skb(skb);
sdata->u.sta.mshstats.dropped_frames_no_route++;
err = -ENOSPC;
goto endlookup;
}
}
if (mpath->flags & MESH_PATH_ACTIVE) {
if (time_after(jiffies, mpath->exp_time -
msecs_to_jiffies(sdata->u.sta.mshcfg.path_refresh_time))
&& skb->pkt_type != PACKET_OTHERHOST
&& !(mpath->flags & MESH_PATH_RESOLVING)
&& !(mpath->flags & MESH_PATH_FIXED)) {
mesh_queue_preq(mpath,
PREQ_Q_F_START | PREQ_Q_F_REFRESH);
}
memcpy(next_hop, mpath->next_hop->addr,
ETH_ALEN);
} else {
if (!(mpath->flags & MESH_PATH_RESOLVING)) {
/* Start discovery only if it is not running yet */
mesh_queue_preq(mpath, PREQ_Q_F_START);
}
if (skb_queue_len(&mpath->frame_queue) >=
MESH_FRAME_QUEUE_LEN) {
skb_to_free = mpath->frame_queue.next;
skb_unlink(skb_to_free, &mpath->frame_queue);
}
skb_queue_tail(&mpath->frame_queue, skb);
if (skb_to_free)
mesh_path_discard_frame(skb_to_free, dev);
err = -ENOENT;
}
endlookup:
rcu_read_unlock();
return err;
}
