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net/mlx4_core: Fix leakage of SW multicast entries
[linux-2.6/btrfs-unstable.git] / net / mac80211 / mesh_plink.c
blob63b874101b2763d5997dc561073e96807596c11a
1 /*
2 * Copyright (c) 2008, 2009 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9 #include <linux/gfp.h>
10 #include <linux/kernel.h>
11 #include <linux/random.h>
12 #include "ieee80211_i.h"
13 #include "rate.h"
14 #include "mesh.h"
15
16 #define PLINK_GET_LLID(p) (p + 2)
17 #define PLINK_GET_PLID(p) (p + 4)
18
19 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
20 jiffies + HZ * t / 1000))
21
22 enum plink_event {
23 PLINK_UNDEFINED,
24 OPN_ACPT,
25 OPN_RJCT,
26 OPN_IGNR,
27 CNF_ACPT,
28 CNF_RJCT,
29 CNF_IGNR,
30 CLS_ACPT,
31 CLS_IGNR
32 };
33
34 static const char * const mplstates[] = {
35 [NL80211_PLINK_LISTEN] = "LISTEN",
36 [NL80211_PLINK_OPN_SNT] = "OPN-SNT",
37 [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD",
38 [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD",
39 [NL80211_PLINK_ESTAB] = "ESTAB",
40 [NL80211_PLINK_HOLDING] = "HOLDING",
41 [NL80211_PLINK_BLOCKED] = "BLOCKED"
42 };
43
44 static const char * const mplevents[] = {
45 [PLINK_UNDEFINED] = "NONE",
46 [OPN_ACPT] = "OPN_ACPT",
47 [OPN_RJCT] = "OPN_RJCT",
48 [OPN_IGNR] = "OPN_IGNR",
49 [CNF_ACPT] = "CNF_ACPT",
50 [CNF_RJCT] = "CNF_RJCT",
51 [CNF_IGNR] = "CNF_IGNR",
52 [CLS_ACPT] = "CLS_ACPT",
53 [CLS_IGNR] = "CLS_IGNR"
54 };
55
56 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
57 enum ieee80211_self_protected_actioncode action,
58 u8 *da, u16 llid, u16 plid, u16 reason);
59
60
61 /* We only need a valid sta if user configured a minimum rssi_threshold. */
62 static bool rssi_threshold_check(struct ieee80211_sub_if_data *sdata,
63 struct sta_info *sta)
64 {
65 s32 rssi_threshold = sdata->u.mesh.mshcfg.rssi_threshold;
66 return rssi_threshold == 0 ||
67 (sta && (s8) -ewma_read(&sta->avg_signal) > rssi_threshold);
68 }
69
70 /**
71 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
72 *
73 * @sta: mesh peer link to restart
74 *
75 * Locking: this function must be called holding sta->lock
76 */
77 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
78 {
79 sta->plink_state = NL80211_PLINK_LISTEN;
80 sta->llid = sta->plid = sta->reason = 0;
81 sta->plink_retries = 0;
82 }
83
84 /*
85 * mesh_set_short_slot_time - enable / disable ERP short slot time.
86 *
87 * The standard indirectly mandates mesh STAs to turn off short slot time by
88 * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we
89 * can't be sneaky about it. Enable short slot time if all mesh STAs in the
90 * MBSS support ERP rates.
91 *
92 * Returns BSS_CHANGED_ERP_SLOT or 0 for no change.
93 */
94 static u32 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata)
95 {
96 struct ieee80211_local *local = sdata->local;
97 enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
98 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
99 struct sta_info *sta;
100 u32 erp_rates = 0, changed = 0;
101 int i;
102 bool short_slot = false;
103
104 if (band == IEEE80211_BAND_5GHZ) {
105 /* (IEEE 802.11-2012 19.4.5) */
106 short_slot = true;
107 goto out;
108 } else if (band != IEEE80211_BAND_2GHZ ||
109 (band == IEEE80211_BAND_2GHZ &&
110 local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
111 goto out;
112
113 for (i = 0; i < sband->n_bitrates; i++)
114 if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G)
115 erp_rates |= BIT(i);
116
117 if (!erp_rates)
118 goto out;
119
120 rcu_read_lock();
121 list_for_each_entry_rcu(sta, &local->sta_list, list) {
122 if (sdata != sta->sdata ||
123 sta->plink_state != NL80211_PLINK_ESTAB)
124 continue;
125
126 short_slot = false;
127 if (erp_rates & sta->sta.supp_rates[band])
128 short_slot = true;
129 else
130 break;
131 }
132 rcu_read_unlock();
133
134 out:
135 if (sdata->vif.bss_conf.use_short_slot != short_slot) {
136 sdata->vif.bss_conf.use_short_slot = short_slot;
137 changed = BSS_CHANGED_ERP_SLOT;
138 mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n",
139 sdata->vif.addr, short_slot);
140 }
141 return changed;
142 }
143
144 /**
145 * mesh_set_ht_prot_mode - set correct HT protection mode
146 *
147 * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT
148 * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT
149 * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is
150 * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode
151 * is selected if all peers in our 20/40MHz MBSS support HT and atleast one
152 * HT20 peer is present. Otherwise no-protection mode is selected.
153 */
154 static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata)
155 {
156 struct ieee80211_local *local = sdata->local;
157 struct sta_info *sta;
158 u16 ht_opmode;
159 bool non_ht_sta = false, ht20_sta = false;
160
161 switch (sdata->vif.bss_conf.chandef.width) {
162 case NL80211_CHAN_WIDTH_20_NOHT:
163 case NL80211_CHAN_WIDTH_5:
164 case NL80211_CHAN_WIDTH_10:
165 return 0;
166 default:
167 break;
168 }
169
170 rcu_read_lock();
171 list_for_each_entry_rcu(sta, &local->sta_list, list) {
172 if (sdata != sta->sdata ||
173 sta->plink_state != NL80211_PLINK_ESTAB)
174 continue;
175
176 if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20)
177 continue;
178
179 if (!sta->sta.ht_cap.ht_supported) {
180 mpl_dbg(sdata, "nonHT sta (%pM) is present\n",
181 sta->sta.addr);
182 non_ht_sta = true;
183 break;
184 }
185
186 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr);
187 ht20_sta = true;
188 }
189 rcu_read_unlock();
190
191 if (non_ht_sta)
192 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED;
193 else if (ht20_sta &&
194 sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20)
195 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ;
196 else
197 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE;
198
199 if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode)
200 return 0;
201
202 sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
203 sdata->u.mesh.mshcfg.ht_opmode = ht_opmode;
204 mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode);
205 return BSS_CHANGED_HT;
206 }
207
208 /**
209 * __mesh_plink_deactivate - deactivate mesh peer link
210 *
211 * @sta: mesh peer link to deactivate
212 *
213 * All mesh paths with this peer as next hop will be flushed
214 * Returns beacon changed flag if the beacon content changed.
215 *
216 * Locking: the caller must hold sta->lock
217 */
218 static u32 __mesh_plink_deactivate(struct sta_info *sta)
219 {
220 struct ieee80211_sub_if_data *sdata = sta->sdata;
221 u32 changed = 0;
222
223 if (sta->plink_state == NL80211_PLINK_ESTAB)
224 changed = mesh_plink_dec_estab_count(sdata);
225 sta->plink_state = NL80211_PLINK_BLOCKED;
226 mesh_path_flush_by_nexthop(sta);
227
228 ieee80211_mps_sta_status_update(sta);
229 changed |= ieee80211_mps_set_sta_local_pm(sta,
230 NL80211_MESH_POWER_UNKNOWN);
231
232 return changed;
233 }
234
235 /**
236 * mesh_plink_deactivate - deactivate mesh peer link
237 *
238 * @sta: mesh peer link to deactivate
239 *
240 * All mesh paths with this peer as next hop will be flushed
241 */
242 u32 mesh_plink_deactivate(struct sta_info *sta)
243 {
244 struct ieee80211_sub_if_data *sdata = sta->sdata;
245 u32 changed;
246
247 spin_lock_bh(&sta->lock);
248 changed = __mesh_plink_deactivate(sta);
249 sta->reason = WLAN_REASON_MESH_PEER_CANCELED;
250 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE,
251 sta->sta.addr, sta->llid, sta->plid,
252 sta->reason);
253 spin_unlock_bh(&sta->lock);
254
255 return changed;
256 }
257
258 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
259 enum ieee80211_self_protected_actioncode action,
260 u8 *da, u16 llid, u16 plid, u16 reason)
261 {
262 struct ieee80211_local *local = sdata->local;
263 struct sk_buff *skb;
264 struct ieee80211_tx_info *info;
265 struct ieee80211_mgmt *mgmt;
266 bool include_plid = false;
267 u16 peering_proto = 0;
268 u8 *pos, ie_len = 4;
269 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.self_prot) +
270 sizeof(mgmt->u.action.u.self_prot);
271 int err = -ENOMEM;
272
273 skb = dev_alloc_skb(local->tx_headroom +
274 hdr_len +
275 2 + /* capability info */
276 2 + /* AID */
277 2 + 8 + /* supported rates */
278 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
279 2 + sdata->u.mesh.mesh_id_len +
280 2 + sizeof(struct ieee80211_meshconf_ie) +
281 2 + sizeof(struct ieee80211_ht_cap) +
282 2 + sizeof(struct ieee80211_ht_operation) +
283 2 + 8 + /* peering IE */
284 sdata->u.mesh.ie_len);
285 if (!skb)
286 return err;
287 info = IEEE80211_SKB_CB(skb);
288 skb_reserve(skb, local->tx_headroom);
289 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
290 memset(mgmt, 0, hdr_len);
291 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
292 IEEE80211_STYPE_ACTION);
293 memcpy(mgmt->da, da, ETH_ALEN);
294 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
295 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
296 mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED;
297 mgmt->u.action.u.self_prot.action_code = action;
298
299 if (action != WLAN_SP_MESH_PEERING_CLOSE) {
300 enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
301
302 /* capability info */
303 pos = skb_put(skb, 2);
304 memset(pos, 0, 2);
305 if (action == WLAN_SP_MESH_PEERING_CONFIRM) {
306 /* AID */
307 pos = skb_put(skb, 2);
308 put_unaligned_le16(plid, pos + 2);
309 }
310 if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
311 ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
312 mesh_add_rsn_ie(sdata, skb) ||
313 mesh_add_meshid_ie(sdata, skb) ||
314 mesh_add_meshconf_ie(sdata, skb))
315 goto free;
316 } else { /* WLAN_SP_MESH_PEERING_CLOSE */
317 info->flags |= IEEE80211_TX_CTL_NO_ACK;
318 if (mesh_add_meshid_ie(sdata, skb))
319 goto free;
320 }
321
322 /* Add Mesh Peering Management element */
323 switch (action) {
324 case WLAN_SP_MESH_PEERING_OPEN:
325 break;
326 case WLAN_SP_MESH_PEERING_CONFIRM:
327 ie_len += 2;
328 include_plid = true;
329 break;
330 case WLAN_SP_MESH_PEERING_CLOSE:
331 if (plid) {
332 ie_len += 2;
333 include_plid = true;
334 }
335 ie_len += 2; /* reason code */
336 break;
337 default:
338 err = -EINVAL;
339 goto free;
340 }
341
342 if (WARN_ON(skb_tailroom(skb) < 2 + ie_len))
343 goto free;
344
345 pos = skb_put(skb, 2 + ie_len);
346 *pos++ = WLAN_EID_PEER_MGMT;
347 *pos++ = ie_len;
348 memcpy(pos, &peering_proto, 2);
349 pos += 2;
350 put_unaligned_le16(llid, pos);
351 pos += 2;
352 if (include_plid) {
353 put_unaligned_le16(plid, pos);
354 pos += 2;
355 }
356 if (action == WLAN_SP_MESH_PEERING_CLOSE) {
357 put_unaligned_le16(reason, pos);
358 pos += 2;
359 }
360
361 if (action != WLAN_SP_MESH_PEERING_CLOSE) {
362 if (mesh_add_ht_cap_ie(sdata, skb) ||
363 mesh_add_ht_oper_ie(sdata, skb))
364 goto free;
365 }
366
367 if (mesh_add_vendor_ies(sdata, skb))
368 goto free;
369
370 ieee80211_tx_skb(sdata, skb);
371 return 0;
372 free:
373 kfree_skb(skb);
374 return err;
375 }
376
377 static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata,
378 struct sta_info *sta,
379 struct ieee802_11_elems *elems, bool insert)
380 {
381 struct ieee80211_local *local = sdata->local;
382 enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
383 struct ieee80211_supported_band *sband;
384 u32 rates, basic_rates = 0, changed = 0;
385
386 sband = local->hw.wiphy->bands[band];
387 rates = ieee80211_sta_get_rates(sdata, elems, band, &basic_rates);
388
389 spin_lock_bh(&sta->lock);
390 sta->last_rx = jiffies;
391
392 /* rates and capabilities don't change during peering */
393 if (sta->plink_state == NL80211_PLINK_ESTAB)
394 goto out;
395
396 if (sta->sta.supp_rates[band] != rates)
397 changed |= IEEE80211_RC_SUPP_RATES_CHANGED;
398 sta->sta.supp_rates[band] = rates;
399
400 if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
401 elems->ht_cap_elem, sta))
402 changed |= IEEE80211_RC_BW_CHANGED;
403
404 /* HT peer is operating 20MHz-only */
405 if (elems->ht_operation &&
406 !(elems->ht_operation->ht_param &
407 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
408 if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20)
409 changed |= IEEE80211_RC_BW_CHANGED;
410 sta->sta.bandwidth = IEEE80211_STA_RX_BW_20;
411 }
412
413 if (insert)
414 rate_control_rate_init(sta);
415 else
416 rate_control_rate_update(local, sband, sta, changed);
417 out:
418 spin_unlock_bh(&sta->lock);
419 }
420
421 static struct sta_info *
422 __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr)
423 {
424 struct sta_info *sta;
425
426 if (sdata->local->num_sta >= MESH_MAX_PLINKS)
427 return NULL;
428
429 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
430 if (!sta)
431 return NULL;
432
433 sta->plink_state = NL80211_PLINK_LISTEN;
434
435 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
436 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
437 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
438
439 set_sta_flag(sta, WLAN_STA_WME);
440 sta->sta.wme = true;
441
442 return sta;
443 }
444
445 static struct sta_info *
446 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
447 struct ieee802_11_elems *elems)
448 {
449 struct sta_info *sta = NULL;
450
451 /* Userspace handles station allocation */
452 if (sdata->u.mesh.user_mpm ||
453 sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED)
454 cfg80211_notify_new_peer_candidate(sdata->dev, addr,
455 elems->ie_start,
456 elems->total_len,
457 GFP_KERNEL);
458 else
459 sta = __mesh_sta_info_alloc(sdata, addr);
460
461 return sta;
462 }
463
464 /*
465 * mesh_sta_info_get - return mesh sta info entry for @addr.
466 *
467 * @sdata: local meshif
468 * @addr: peer's address
469 * @elems: IEs from beacon or mesh peering frame.
470 *
471 * Return existing or newly allocated sta_info under RCU read lock.
472 * (re)initialize with given IEs.
473 */
474 static struct sta_info *
475 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
476 u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU)
477 {
478 struct sta_info *sta = NULL;
479
480 rcu_read_lock();
481 sta = sta_info_get(sdata, addr);
482 if (sta) {
483 mesh_sta_info_init(sdata, sta, elems, false);
484 } else {
485 rcu_read_unlock();
486 /* can't run atomic */
487 sta = mesh_sta_info_alloc(sdata, addr, elems);
488 if (!sta) {
489 rcu_read_lock();
490 return NULL;
491 }
492
493 mesh_sta_info_init(sdata, sta, elems, true);
494
495 if (sta_info_insert_rcu(sta))
496 return NULL;
497 }
498
499 return sta;
500 }
501
502 /*
503 * mesh_neighbour_update - update or initialize new mesh neighbor.
504 *
505 * @sdata: local meshif
506 * @addr: peer's address
507 * @elems: IEs from beacon or mesh peering frame
508 *
509 * Initiates peering if appropriate.
510 */
511 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
512 u8 *hw_addr,
513 struct ieee802_11_elems *elems)
514 {
515 struct sta_info *sta;
516 u32 changed = 0;
517
518 sta = mesh_sta_info_get(sdata, hw_addr, elems);
519 if (!sta)
520 goto out;
521
522 if (mesh_peer_accepts_plinks(elems) &&
523 sta->plink_state == NL80211_PLINK_LISTEN &&
524 sdata->u.mesh.accepting_plinks &&
525 sdata->u.mesh.mshcfg.auto_open_plinks &&
526 rssi_threshold_check(sdata, sta))
527 changed = mesh_plink_open(sta);
528
529 ieee80211_mps_frame_release(sta, elems);
530 out:
531 rcu_read_unlock();
532 ieee80211_mbss_info_change_notify(sdata, changed);
533 }
534
535 static void mesh_plink_timer(unsigned long data)
536 {
537 struct sta_info *sta;
538 u16 reason = 0;
539 struct ieee80211_sub_if_data *sdata;
540 struct mesh_config *mshcfg;
541 enum ieee80211_self_protected_actioncode action = 0;
542
543 /*
544 * This STA is valid because sta_info_destroy() will
545 * del_timer_sync() this timer after having made sure
546 * it cannot be readded (by deleting the plink.)
547 */
548 sta = (struct sta_info *) data;
549
550 if (sta->sdata->local->quiescing)
551 return;
552
553 spin_lock_bh(&sta->lock);
554
555 /* If a timer fires just before a state transition on another CPU,
556 * we may have already extended the timeout and changed state by the
557 * time we've acquired the lock and arrived here. In that case,
558 * skip this timer and wait for the new one.
559 */
560 if (time_before(jiffies, sta->plink_timer.expires)) {
561 mpl_dbg(sta->sdata,
562 "Ignoring timer for %pM in state %s (timer adjusted)",
563 sta->sta.addr, mplstates[sta->plink_state]);
564 spin_unlock_bh(&sta->lock);
565 return;
566 }
567
568 /* del_timer() and handler may race when entering these states */
569 if (sta->plink_state == NL80211_PLINK_LISTEN ||
570 sta->plink_state == NL80211_PLINK_ESTAB) {
571 mpl_dbg(sta->sdata,
572 "Ignoring timer for %pM in state %s (timer deleted)",
573 sta->sta.addr, mplstates[sta->plink_state]);
574 spin_unlock_bh(&sta->lock);
575 return;
576 }
577
578 mpl_dbg(sta->sdata,
579 "Mesh plink timer for %pM fired on state %s\n",
580 sta->sta.addr, mplstates[sta->plink_state]);
581 sdata = sta->sdata;
582 mshcfg = &sdata->u.mesh.mshcfg;
583
584 switch (sta->plink_state) {
585 case NL80211_PLINK_OPN_RCVD:
586 case NL80211_PLINK_OPN_SNT:
587 /* retry timer */
588 if (sta->plink_retries < mshcfg->dot11MeshMaxRetries) {
589 u32 rand;
590 mpl_dbg(sta->sdata,
591 "Mesh plink for %pM (retry, timeout): %d %d\n",
592 sta->sta.addr, sta->plink_retries,
593 sta->plink_timeout);
594 get_random_bytes(&rand, sizeof(u32));
595 sta->plink_timeout = sta->plink_timeout +
596 rand % sta->plink_timeout;
597 ++sta->plink_retries;
598 mod_plink_timer(sta, sta->plink_timeout);
599 action = WLAN_SP_MESH_PEERING_OPEN;
600 break;
601 }
602 reason = WLAN_REASON_MESH_MAX_RETRIES;
603 /* fall through on else */
604 case NL80211_PLINK_CNF_RCVD:
605 /* confirm timer */
606 if (!reason)
607 reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT;
608 sta->plink_state = NL80211_PLINK_HOLDING;
609 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
610 action = WLAN_SP_MESH_PEERING_CLOSE;
611 break;
612 case NL80211_PLINK_HOLDING:
613 /* holding timer */
614 del_timer(&sta->plink_timer);
615 mesh_plink_fsm_restart(sta);
616 break;
617 default:
618 break;
619 }
620 spin_unlock_bh(&sta->lock);
621 if (action)
622 mesh_plink_frame_tx(sdata, action, sta->sta.addr,
623 sta->llid, sta->plid, reason);
624 }
625
626 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
627 {
628 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
629 sta->plink_timer.data = (unsigned long) sta;
630 sta->plink_timer.function = mesh_plink_timer;
631 sta->plink_timeout = timeout;
632 add_timer(&sta->plink_timer);
633 }
634
635 static bool llid_in_use(struct ieee80211_sub_if_data *sdata,
636 u16 llid)
637 {
638 struct ieee80211_local *local = sdata->local;
639 bool in_use = false;
640 struct sta_info *sta;
641
642 rcu_read_lock();
643 list_for_each_entry_rcu(sta, &local->sta_list, list) {
644 if (!memcmp(&sta->llid, &llid, sizeof(llid))) {
645 in_use = true;
646 break;
647 }
648 }
649 rcu_read_unlock();
650
651 return in_use;
652 }
653
654 static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata)
655 {
656 u16 llid;
657
658 do {
659 get_random_bytes(&llid, sizeof(llid));
660 /* for mesh PS we still only have the AID range for TIM bits */
661 llid = (llid % IEEE80211_MAX_AID) + 1;
662 } while (llid_in_use(sdata, llid));
663
664 return llid;
665 }
666
667 u32 mesh_plink_open(struct sta_info *sta)
668 {
669 struct ieee80211_sub_if_data *sdata = sta->sdata;
670 u32 changed;
671
672 if (!test_sta_flag(sta, WLAN_STA_AUTH))
673 return 0;
674
675 spin_lock_bh(&sta->lock);
676 sta->llid = mesh_get_new_llid(sdata);
677 if (sta->plink_state != NL80211_PLINK_LISTEN &&
678 sta->plink_state != NL80211_PLINK_BLOCKED) {
679 spin_unlock_bh(&sta->lock);
680 return 0;
681 }
682 sta->plink_state = NL80211_PLINK_OPN_SNT;
683 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout);
684 spin_unlock_bh(&sta->lock);
685 mpl_dbg(sdata,
686 "Mesh plink: starting establishment with %pM\n",
687 sta->sta.addr);
688
689 /* set the non-peer mode to active during peering */
690 changed = ieee80211_mps_local_status_update(sdata);
691
692 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN,
693 sta->sta.addr, sta->llid, 0, 0);
694 return changed;
695 }
696
697 u32 mesh_plink_block(struct sta_info *sta)
698 {
699 u32 changed;
700
701 spin_lock_bh(&sta->lock);
702 changed = __mesh_plink_deactivate(sta);
703 sta->plink_state = NL80211_PLINK_BLOCKED;
704 spin_unlock_bh(&sta->lock);
705
706 return changed;
707 }
708
709 static void mesh_plink_close(struct ieee80211_sub_if_data *sdata,
710 struct sta_info *sta,
711 enum plink_event event)
712 {
713 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
714
715 u16 reason = (event == CLS_ACPT) ?
716 WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG;
717
718 sta->reason = reason;
719 sta->plink_state = NL80211_PLINK_HOLDING;
720 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
721 }
722
723 static u32 mesh_plink_establish(struct ieee80211_sub_if_data *sdata,
724 struct sta_info *sta)
725 {
726 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
727 u32 changed = 0;
728
729 del_timer(&sta->plink_timer);
730 sta->plink_state = NL80211_PLINK_ESTAB;
731 changed |= mesh_plink_inc_estab_count(sdata);
732 changed |= mesh_set_ht_prot_mode(sdata);
733 changed |= mesh_set_short_slot_time(sdata);
734 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr);
735 ieee80211_mps_sta_status_update(sta);
736 changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode);
737 return changed;
738 }
739
740 /**
741 * mesh_plink_fsm - step @sta MPM based on @event
742 *
743 * @sdata: interface
744 * @sta: mesh neighbor
745 * @event: peering event
746 *
747 * Return: changed MBSS flags
748 */
749 static u32 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata,
750 struct sta_info *sta, enum plink_event event)
751 {
752 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
753 enum ieee80211_self_protected_actioncode action = 0;
754 u32 changed = 0;
755
756 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr,
757 mplstates[sta->plink_state], mplevents[event]);
758
759 spin_lock_bh(&sta->lock);
760 switch (sta->plink_state) {
761 case NL80211_PLINK_LISTEN:
762 switch (event) {
763 case CLS_ACPT:
764 mesh_plink_fsm_restart(sta);
765 break;
766 case OPN_ACPT:
767 sta->plink_state = NL80211_PLINK_OPN_RCVD;
768 sta->llid = mesh_get_new_llid(sdata);
769 mesh_plink_timer_set(sta,
770 mshcfg->dot11MeshRetryTimeout);
771
772 /* set the non-peer mode to active during peering */
773 changed |= ieee80211_mps_local_status_update(sdata);
774 action = WLAN_SP_MESH_PEERING_OPEN;
775 break;
776 default:
777 break;
778 }
779 break;
780 case NL80211_PLINK_OPN_SNT:
781 switch (event) {
782 case OPN_RJCT:
783 case CNF_RJCT:
784 case CLS_ACPT:
785 mesh_plink_close(sdata, sta, event);
786 action = WLAN_SP_MESH_PEERING_CLOSE;
787 break;
788 case OPN_ACPT:
789 /* retry timer is left untouched */
790 sta->plink_state = NL80211_PLINK_OPN_RCVD;
791 action = WLAN_SP_MESH_PEERING_CONFIRM;
792 break;
793 case CNF_ACPT:
794 sta->plink_state = NL80211_PLINK_CNF_RCVD;
795 mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout);
796 break;
797 default:
798 break;
799 }
800 break;
801 case NL80211_PLINK_OPN_RCVD:
802 switch (event) {
803 case OPN_RJCT:
804 case CNF_RJCT:
805 case CLS_ACPT:
806 mesh_plink_close(sdata, sta, event);
807 action = WLAN_SP_MESH_PEERING_CLOSE;
808 break;
809 case OPN_ACPT:
810 action = WLAN_SP_MESH_PEERING_CONFIRM;
811 break;
812 case CNF_ACPT:
813 changed |= mesh_plink_establish(sdata, sta);
814 break;
815 default:
816 break;
817 }
818 break;
819 case NL80211_PLINK_CNF_RCVD:
820 switch (event) {
821 case OPN_RJCT:
822 case CNF_RJCT:
823 case CLS_ACPT:
824 mesh_plink_close(sdata, sta, event);
825 action = WLAN_SP_MESH_PEERING_CLOSE;
826 break;
827 case OPN_ACPT:
828 changed |= mesh_plink_establish(sdata, sta);
829 action = WLAN_SP_MESH_PEERING_CONFIRM;
830 break;
831 default:
832 break;
833 }
834 break;
835 case NL80211_PLINK_ESTAB:
836 switch (event) {
837 case CLS_ACPT:
838 changed |= __mesh_plink_deactivate(sta);
839 changed |= mesh_set_ht_prot_mode(sdata);
840 changed |= mesh_set_short_slot_time(sdata);
841 mesh_plink_close(sdata, sta, event);
842 action = WLAN_SP_MESH_PEERING_CLOSE;
843 break;
844 case OPN_ACPT:
845 action = WLAN_SP_MESH_PEERING_CONFIRM;
846 break;
847 default:
848 break;
849 }
850 break;
851 case NL80211_PLINK_HOLDING:
852 switch (event) {
853 case CLS_ACPT:
854 del_timer(&sta->plink_timer);
855 mesh_plink_fsm_restart(sta);
856 break;
857 case OPN_ACPT:
858 case CNF_ACPT:
859 case OPN_RJCT:
860 case CNF_RJCT:
861 action = WLAN_SP_MESH_PEERING_CLOSE;
862 break;
863 default:
864 break;
865 }
866 break;
867 default:
868 /* should not get here, PLINK_BLOCKED is dealt with at the
869 * beginning of the function
870 */
871 break;
872 }
873 spin_unlock_bh(&sta->lock);
874 if (action) {
875 mesh_plink_frame_tx(sdata, action, sta->sta.addr,
876 sta->llid, sta->plid, sta->reason);
877
878 /* also send confirm in open case */
879 if (action == WLAN_SP_MESH_PEERING_OPEN) {
880 mesh_plink_frame_tx(sdata,
881 WLAN_SP_MESH_PEERING_CONFIRM,
882 sta->sta.addr, sta->llid,
883 sta->plid, 0);
884 }
885 }
886
887 return changed;
888 }
889
890 /*
891 * mesh_plink_get_event - get correct MPM event
892 *
893 * @sdata: interface
894 * @sta: peer, leave NULL if processing a frame from a new suitable peer
895 * @elems: peering management IEs
896 * @ftype: frame type
897 * @llid: peer's peer link ID
898 * @plid: peer's local link ID
899 *
900 * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as
901 * an error.
902 */
903 static enum plink_event
904 mesh_plink_get_event(struct ieee80211_sub_if_data *sdata,
905 struct sta_info *sta,
906 struct ieee802_11_elems *elems,
907 enum ieee80211_self_protected_actioncode ftype,
908 u16 llid, u16 plid)
909 {
910 enum plink_event event = PLINK_UNDEFINED;
911 u8 ie_len = elems->peering_len;
912 bool matches_local;
913
914 matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE ||
915 mesh_matches_local(sdata, elems));
916
917 /* deny open request from non-matching peer */
918 if (!matches_local && !sta) {
919 event = OPN_RJCT;
920 goto out;
921 }
922
923 if (!sta) {
924 if (ftype != WLAN_SP_MESH_PEERING_OPEN) {
925 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n");
926 goto out;
927 }
928 /* ftype == WLAN_SP_MESH_PEERING_OPEN */
929 if (!mesh_plink_free_count(sdata)) {
930 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n");
931 goto out;
932 }
933 } else {
934 if (!test_sta_flag(sta, WLAN_STA_AUTH)) {
935 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n");
936 goto out;
937 }
938 if (sta->plink_state == NL80211_PLINK_BLOCKED)
939 goto out;
940 }
941
942 /* new matching peer */
943 if (!sta) {
944 event = OPN_ACPT;
945 goto out;
946 }
947
948 switch (ftype) {
949 case WLAN_SP_MESH_PEERING_OPEN:
950 if (!matches_local)
951 event = OPN_RJCT;
952 if (!mesh_plink_free_count(sdata) ||
953 (sta->plid && sta->plid != plid))
954 event = OPN_IGNR;
955 else
956 event = OPN_ACPT;
957 break;
958 case WLAN_SP_MESH_PEERING_CONFIRM:
959 if (!matches_local)
960 event = CNF_RJCT;
961 if (!mesh_plink_free_count(sdata) ||
962 (sta->llid != llid || sta->plid != plid))
963 event = CNF_IGNR;
964 else
965 event = CNF_ACPT;
966 break;
967 case WLAN_SP_MESH_PEERING_CLOSE:
968 if (sta->plink_state == NL80211_PLINK_ESTAB)
969 /* Do not check for llid or plid. This does not
970 * follow the standard but since multiple plinks
971 * per sta are not supported, it is necessary in
972 * order to avoid a livelock when MP A sees an
973 * establish peer link to MP B but MP B does not
974 * see it. This can be caused by a timeout in
975 * B's peer link establishment or B beign
976 * restarted.
977 */
978 event = CLS_ACPT;
979 else if (sta->plid != plid)
980 event = CLS_IGNR;
981 else if (ie_len == 8 && sta->llid != llid)
982 event = CLS_IGNR;
983 else
984 event = CLS_ACPT;
985 break;
986 default:
987 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n");
988 break;
989 }
990
991 out:
992 return event;
993 }
994
995 static void
996 mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata,
997 struct ieee80211_mgmt *mgmt,
998 struct ieee802_11_elems *elems)
999 {
1000
1001 struct sta_info *sta;
1002 enum plink_event event;
1003 enum ieee80211_self_protected_actioncode ftype;
1004 u32 changed = 0;
1005 u8 ie_len = elems->peering_len;
1006 __le16 _plid, _llid;
1007 u16 plid, llid = 0;
1008
1009 if (!elems->peering) {
1010 mpl_dbg(sdata,
1011 "Mesh plink: missing necessary peer link ie\n");
1012 return;
1013 }
1014
1015 if (elems->rsn_len &&
1016 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
1017 mpl_dbg(sdata,
1018 "Mesh plink: can't establish link with secure peer\n");
1019 return;
1020 }
1021
1022 ftype = mgmt->u.action.u.self_prot.action_code;
1023 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) ||
1024 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) ||
1025 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6
1026 && ie_len != 8)) {
1027 mpl_dbg(sdata,
1028 "Mesh plink: incorrect plink ie length %d %d\n",
1029 ftype, ie_len);
1030 return;
1031 }
1032
1033 if (ftype != WLAN_SP_MESH_PEERING_CLOSE &&
1034 (!elems->mesh_id || !elems->mesh_config)) {
1035 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n");
1036 return;
1037 }
1038 /* Note the lines below are correct, the llid in the frame is the plid
1039 * from the point of view of this host.
1040 */
1041 memcpy(&_plid, PLINK_GET_LLID(elems->peering), sizeof(__le16));
1042 plid = le16_to_cpu(_plid);
1043 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM ||
1044 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) {
1045 memcpy(&_llid, PLINK_GET_PLID(elems->peering), sizeof(__le16));
1046 llid = le16_to_cpu(_llid);
1047 }
1048
1049 /* WARNING: Only for sta pointer, is dropped & re-acquired */
1050 rcu_read_lock();
1051
1052 sta = sta_info_get(sdata, mgmt->sa);
1053
1054 if (ftype == WLAN_SP_MESH_PEERING_OPEN &&
1055 !rssi_threshold_check(sdata, sta)) {
1056 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n",
1057 mgmt->sa);
1058 goto unlock_rcu;
1059 }
1060
1061 /* Now we will figure out the appropriate event... */
1062 event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid);
1063
1064 if (event == OPN_ACPT) {
1065 rcu_read_unlock();
1066 /* allocate sta entry if necessary and update info */
1067 sta = mesh_sta_info_get(sdata, mgmt->sa, elems);
1068 if (!sta) {
1069 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n");
1070 goto unlock_rcu;
1071 }
1072 sta->plid = plid;
1073 } else if (!sta && event == OPN_RJCT) {
1074 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE,
1075 mgmt->sa, 0, plid,
1076 WLAN_REASON_MESH_CONFIG);
1077 goto unlock_rcu;
1078 } else if (!sta || event == PLINK_UNDEFINED) {
1079 /* something went wrong */
1080 goto unlock_rcu;
1081 }
1082
1083 changed |= mesh_plink_fsm(sdata, sta, event);
1084
1085 unlock_rcu:
1086 rcu_read_unlock();
1087
1088 if (changed)
1089 ieee80211_mbss_info_change_notify(sdata, changed);
1090 }
1091
1092 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
1093 struct ieee80211_mgmt *mgmt, size_t len,
1094 struct ieee80211_rx_status *rx_status)
1095 {
1096 struct ieee802_11_elems elems;
1097 size_t baselen;
1098 u8 *baseaddr;
1099
1100 /* need action_code, aux */
1101 if (len < IEEE80211_MIN_ACTION_SIZE + 3)
1102 return;
1103
1104 if (sdata->u.mesh.user_mpm)
1105 /* userspace must register for these */
1106 return;
1107
1108 if (is_multicast_ether_addr(mgmt->da)) {
1109 mpl_dbg(sdata,
1110 "Mesh plink: ignore frame from multicast address\n");
1111 return;
1112 }
1113
1114 baseaddr = mgmt->u.action.u.self_prot.variable;
1115 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt;
1116 if (mgmt->u.action.u.self_prot.action_code ==
1117 WLAN_SP_MESH_PEERING_CONFIRM) {
1118 baseaddr += 4;
1119 baselen += 4;
1120 }
1121 ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems);
1122 mesh_process_plink_frame(sdata, mgmt, &elems);
1123 }
(deprecated) Btrfs devel tree