/**
* 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;
}
void mesh_path_timer(unsigned long data)
{
struct ieee80211_sub_if_data *sdata;
struct mesh_path *mpath;
rcu_read_lock();
mpath = (struct mesh_path *) data;
mpath = rcu_dereference(mpath);
if (!mpath)
goto endmpathtimer;
sdata = mpath->sdata;
if (sdata->local->quiescing) {
rcu_read_unlock();
return;
}
spin_lock_bh(&mpath->state_lock);
if (mpath->flags & MESH_PATH_RESOLVED ||
(!(mpath->flags & MESH_PATH_RESOLVING)))
mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
else if (mpath->discovery_retries < max_preq_retries(sdata)) {
++mpath->discovery_retries;
mpath->discovery_timeout *= 2;
mesh_queue_preq(mpath, 0);
} else {
mpath->flags = 0;
mpath->exp_time = jiffies;
mesh_path_flush_pending(mpath);
}
spin_unlock_bh(&mpath->state_lock);
endmpathtimer:
rcu_read_unlock();
}
void mesh_path_timer(unsigned long data)
{
struct mesh_path *mpath = (void *) data;
struct ieee80211_sub_if_data *sdata = mpath->sdata;
int ret;
if (sdata->local->quiescing)
return;
spin_lock_bh(&mpath->state_lock);
if (mpath->flags & MESH_PATH_RESOLVED ||
(!(mpath->flags & MESH_PATH_RESOLVING))) {
mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
spin_unlock_bh(&mpath->state_lock);
} else if (mpath->discovery_retries < max_preq_retries(sdata)) {
++mpath->discovery_retries;
mpath->discovery_timeout *= 2;
mpath->flags &= ~MESH_PATH_REQ_QUEUED;
spin_unlock_bh(&mpath->state_lock);
mesh_queue_preq(mpath, 0);
} else {
mpath->flags = 0;
mpath->exp_time = jiffies;
spin_unlock_bh(&mpath->state_lock);
if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
ret = mesh_path_send_to_gates(mpath);
if (ret)
mhwmp_dbg(sdata, "no gate was reachable\n");
} else
mesh_path_flush_pending(mpath);
}
}
/**
* mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
* this function is considered "using" the associated mpath, so preempt a path
* refresh if this mpath expires soon.
*
* @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.
*/
int mesh_nexthop_lookup(struct sk_buff *skb,
struct ieee80211_sub_if_data *sdata)
{
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 = -ENOENT;
rcu_read_lock();
mpath = mesh_path_lookup(target_addr, sdata);
if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
goto endlookup;
if (time_after(jiffies,
mpath->exp_time -
msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
!(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);
memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
err = 0;
}
endlookup:
rcu_read_unlock();
return err;
}
static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
struct ieee80211_rann_ie *rann)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct mesh_path *mpath;
u8 ttl, flags, hopcount;
u8 *orig_addr;
u32 orig_sn, metric;
ttl = rann->rann_ttl;
if (ttl <= 1) {
ifmsh->mshstats.dropped_frames_ttl++;
return;
}
ttl--;
flags = rann->rann_flags;
orig_addr = rann->rann_addr;
orig_sn = rann->rann_seq;
hopcount = rann->rann_hopcount;
hopcount++;
metric = rann->rann_metric;
mhwmp_dbg("received RANN from %pM\n", orig_addr);
rcu_read_lock();
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
mesh_path_add(orig_addr, sdata);
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
rcu_read_unlock();
sdata->u.mesh.mshstats.dropped_frames_no_route++;
return;
}
mesh_queue_preq(mpath,
PREQ_Q_F_START | PREQ_Q_F_REFRESH);
}
if (mpath->sn < orig_sn) {
mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
cpu_to_le32(orig_sn),
0, NULL, 0, broadcast_addr,
hopcount, ttl, 0,
cpu_to_le32(metric + mpath->metric),
0, sdata);
mpath->sn = orig_sn;
}
rcu_read_unlock();
}
/**
* 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;
}
static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
struct ieee80211_rann_ie *rann)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
struct mesh_path *mpath;
u8 ttl, flags, hopcount;
u8 *orig_addr;
u32 orig_sn, metric, metric_txsta, interval;
bool root_is_gate;
ttl = rann->rann_ttl;
flags = rann->rann_flags;
root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
orig_addr = rann->rann_addr;
orig_sn = le32_to_cpu(rann->rann_seq);
interval = le32_to_cpu(rann->rann_interval);
hopcount = rann->rann_hopcount;
hopcount++;
metric = le32_to_cpu(rann->rann_metric);
/* Ignore our own RANNs */
if (ether_addr_equal(orig_addr, sdata->vif.addr))
return;
mhwmp_dbg(sdata,
"received RANN from %pM via neighbour %pM (is_gate=%d)\n",
orig_addr, mgmt->sa, root_is_gate);
rcu_read_lock();
sta = sta_info_get(sdata, mgmt->sa);
if (!sta) {
rcu_read_unlock();
return;
}
metric_txsta = airtime_link_metric_get(local, sta);
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
mesh_path_add(orig_addr, sdata);
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
rcu_read_unlock();
sdata->u.mesh.mshstats.dropped_frames_no_route++;
return;
}
}
if (!(SN_LT(mpath->sn, orig_sn)) &&
!(mpath->sn == orig_sn && metric < mpath->rann_metric)) {
rcu_read_unlock();
return;
}
if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
(time_after(jiffies, mpath->last_preq_to_root +
root_path_confirmation_jiffies(sdata)) ||
time_before(jiffies, mpath->last_preq_to_root))) &&
!(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
mhwmp_dbg(sdata,
"time to refresh root mpath %pM\n",
orig_addr);
mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
mpath->last_preq_to_root = jiffies;
}
mpath->sn = orig_sn;
mpath->rann_metric = metric + metric_txsta;
mpath->is_root = true;
/* Recording RANNs sender address to send individually
* addressed PREQs destined for root mesh STA */
memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
if (root_is_gate)
mesh_path_add_gate(mpath);
if (ttl <= 1) {
ifmsh->mshstats.dropped_frames_ttl++;
rcu_read_unlock();
return;
}
ttl--;
if (ifmsh->mshcfg.dot11MeshForwarding) {
mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
cpu_to_le32(orig_sn),
0, NULL, 0, broadcast_addr,
hopcount, ttl, cpu_to_le32(interval),
cpu_to_le32(metric + metric_txsta),
0, sdata);
}
rcu_read_unlock();
}
static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
struct ieee80211_rann_ie *rann)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct mesh_path *mpath;
u8 ttl, flags, hopcount;
u8 *orig_addr;
u32 orig_sn, metric;
u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
bool root_is_gate;
ttl = rann->rann_ttl;
if (ttl <= 1) {
ifmsh->mshstats.dropped_frames_ttl++;
return;
}
ttl--;
flags = rann->rann_flags;
root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
orig_addr = rann->rann_addr;
orig_sn = rann->rann_seq;
hopcount = rann->rann_hopcount;
hopcount++;
metric = rann->rann_metric;
if (memcmp(orig_addr, sdata->vif.addr, ETH_ALEN) == 0)
return;
mhwmp_dbg("received RANN from %pM (is_gate=%d)", orig_addr,
root_is_gate);
rcu_read_lock();
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
mesh_path_add(orig_addr, sdata);
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
rcu_read_unlock();
sdata->u.mesh.mshstats.dropped_frames_no_route++;
return;
}
}
if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
time_after(jiffies, mpath->exp_time - 1*HZ)) &&
!(mpath->flags & MESH_PATH_FIXED)) {
mhwmp_dbg("%s time to refresh root mpath %pM", sdata->name,
orig_addr);
mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
}
if (mpath->sn < orig_sn) {
mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
cpu_to_le32(orig_sn),
0, NULL, 0, broadcast_addr,
hopcount, ttl, cpu_to_le32(interval),
cpu_to_le32(metric + mpath->metric),
0, sdata);
mpath->sn = orig_sn;
}
if (root_is_gate)
mesh_path_add_gate(mpath);
rcu_read_unlock();
}
