1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (c) 2008, 2009 open80211s Ltd. |
4 | * Copyright (C) 2019, 2021-2024 Intel Corporation |
5 | * Author: Luis Carlos Cobo <luisca@cozybit.com> |
6 | */ |
7 | #include <linux/gfp.h> |
8 | #include <linux/kernel.h> |
9 | #include <linux/random.h> |
10 | #include <linux/rculist.h> |
11 | |
12 | #include "ieee80211_i.h" |
13 | #include "rate.h" |
14 | #include "mesh.h" |
15 | |
16 | #define PLINK_CNF_AID(mgmt) ((mgmt)->u.action.u.self_prot.variable + 2) |
17 | #define PLINK_GET_LLID(p) (p + 2) |
18 | #define PLINK_GET_PLID(p) (p + 4) |
19 | |
20 | #define mod_plink_timer(s, t) (mod_timer(&s->mesh->plink_timer, \ |
21 | jiffies + msecs_to_jiffies(t))) |
22 | |
23 | enum plink_event { |
24 | PLINK_UNDEFINED, |
25 | OPN_ACPT, |
26 | OPN_RJCT, |
27 | OPN_IGNR, |
28 | CNF_ACPT, |
29 | CNF_RJCT, |
30 | CNF_IGNR, |
31 | CLS_ACPT, |
32 | CLS_IGNR |
33 | }; |
34 | |
35 | static const char * const mplstates[] = { |
36 | [NL80211_PLINK_LISTEN] = "LISTEN" , |
37 | [NL80211_PLINK_OPN_SNT] = "OPN-SNT" , |
38 | [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD" , |
39 | [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD" , |
40 | [NL80211_PLINK_ESTAB] = "ESTAB" , |
41 | [NL80211_PLINK_HOLDING] = "HOLDING" , |
42 | [NL80211_PLINK_BLOCKED] = "BLOCKED" |
43 | }; |
44 | |
45 | static const char * const mplevents[] = { |
46 | [PLINK_UNDEFINED] = "NONE" , |
47 | [OPN_ACPT] = "OPN_ACPT" , |
48 | [OPN_RJCT] = "OPN_RJCT" , |
49 | [OPN_IGNR] = "OPN_IGNR" , |
50 | [CNF_ACPT] = "CNF_ACPT" , |
51 | [CNF_RJCT] = "CNF_RJCT" , |
52 | [CNF_IGNR] = "CNF_IGNR" , |
53 | [CLS_ACPT] = "CLS_ACPT" , |
54 | [CLS_IGNR] = "CLS_IGNR" |
55 | }; |
56 | |
57 | /* We only need a valid sta if user configured a minimum rssi_threshold. */ |
58 | static bool (struct ieee80211_sub_if_data *sdata, |
59 | struct sta_info *sta) |
60 | { |
61 | s32 = sdata->u.mesh.mshcfg.rssi_threshold; |
62 | return rssi_threshold == 0 || |
63 | (sta && |
64 | (s8)-ewma_signal_read(e: &sta->deflink.rx_stats_avg.signal) > |
65 | rssi_threshold); |
66 | } |
67 | |
68 | /** |
69 | * mesh_plink_fsm_restart - restart a mesh peer link finite state machine |
70 | * |
71 | * @sta: mesh peer link to restart |
72 | * |
73 | * Locking: this function must be called holding sta->mesh->plink_lock |
74 | */ |
75 | static inline void mesh_plink_fsm_restart(struct sta_info *sta) |
76 | { |
77 | lockdep_assert_held(&sta->mesh->plink_lock); |
78 | sta->mesh->plink_state = NL80211_PLINK_LISTEN; |
79 | sta->mesh->llid = sta->mesh->plid = sta->mesh->reason = 0; |
80 | sta->mesh->plink_retries = 0; |
81 | } |
82 | |
83 | /* |
84 | * mesh_set_short_slot_time - enable / disable ERP short slot time. |
85 | * |
86 | * The standard indirectly mandates mesh STAs to turn off short slot time by |
87 | * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we |
88 | * can't be sneaky about it. Enable short slot time if all mesh STAs in the |
89 | * MBSS support ERP rates. |
90 | * |
91 | * Returns BSS_CHANGED_ERP_SLOT or 0 for no change. |
92 | */ |
93 | static u64 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata) |
94 | { |
95 | struct ieee80211_local *local = sdata->local; |
96 | struct ieee80211_supported_band *sband; |
97 | struct sta_info *sta; |
98 | u32 erp_rates = 0; |
99 | u64 changed = 0; |
100 | int i; |
101 | bool short_slot = false; |
102 | |
103 | sband = ieee80211_get_sband(sdata); |
104 | if (!sband) |
105 | return changed; |
106 | |
107 | if (sband->band == NL80211_BAND_5GHZ) { |
108 | /* (IEEE 802.11-2012 19.4.5) */ |
109 | short_slot = true; |
110 | goto out; |
111 | } else if (sband->band != NL80211_BAND_2GHZ) { |
112 | goto out; |
113 | } |
114 | |
115 | for (i = 0; i < sband->n_bitrates; i++) |
116 | if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G) |
117 | erp_rates |= BIT(i); |
118 | |
119 | if (!erp_rates) |
120 | goto out; |
121 | |
122 | rcu_read_lock(); |
123 | list_for_each_entry_rcu(sta, &local->sta_list, list) { |
124 | if (sdata != sta->sdata || |
125 | sta->mesh->plink_state != NL80211_PLINK_ESTAB) |
126 | continue; |
127 | |
128 | short_slot = false; |
129 | if (erp_rates & sta->sta.deflink.supp_rates[sband->band]) |
130 | short_slot = true; |
131 | else |
132 | break; |
133 | } |
134 | rcu_read_unlock(); |
135 | |
136 | out: |
137 | if (sdata->vif.bss_conf.use_short_slot != short_slot) { |
138 | sdata->vif.bss_conf.use_short_slot = short_slot; |
139 | changed = BSS_CHANGED_ERP_SLOT; |
140 | mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n" , |
141 | sdata->vif.addr, short_slot); |
142 | } |
143 | return changed; |
144 | } |
145 | |
146 | /** |
147 | * mesh_set_ht_prot_mode - set correct HT protection mode |
148 | * @sdata: the (mesh) interface to handle |
149 | * |
150 | * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT |
151 | * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT |
152 | * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is |
153 | * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode |
154 | * is selected if all peers in our 20/40MHz MBSS support HT and at least one |
155 | * HT20 peer is present. Otherwise no-protection mode is selected. |
156 | * |
157 | * Returns: BSS_CHANGED_HT or 0 for no change |
158 | */ |
159 | static u64 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata) |
160 | { |
161 | struct ieee80211_local *local = sdata->local; |
162 | struct sta_info *sta; |
163 | u16 ht_opmode; |
164 | bool non_ht_sta = false, ht20_sta = false; |
165 | |
166 | switch (sdata->vif.bss_conf.chanreq.oper.width) { |
167 | case NL80211_CHAN_WIDTH_20_NOHT: |
168 | case NL80211_CHAN_WIDTH_5: |
169 | case NL80211_CHAN_WIDTH_10: |
170 | return 0; |
171 | default: |
172 | break; |
173 | } |
174 | |
175 | rcu_read_lock(); |
176 | list_for_each_entry_rcu(sta, &local->sta_list, list) { |
177 | if (sdata != sta->sdata || |
178 | sta->mesh->plink_state != NL80211_PLINK_ESTAB) |
179 | continue; |
180 | |
181 | if (sta->sta.deflink.bandwidth > IEEE80211_STA_RX_BW_20) |
182 | continue; |
183 | |
184 | if (!sta->sta.deflink.ht_cap.ht_supported) { |
185 | mpl_dbg(sdata, "nonHT sta (%pM) is present\n" , |
186 | sta->sta.addr); |
187 | non_ht_sta = true; |
188 | break; |
189 | } |
190 | |
191 | mpl_dbg(sdata, "HT20 sta (%pM) is present\n" , sta->sta.addr); |
192 | ht20_sta = true; |
193 | } |
194 | rcu_read_unlock(); |
195 | |
196 | if (non_ht_sta) |
197 | ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; |
198 | else if (ht20_sta && |
199 | sdata->vif.bss_conf.chanreq.oper.width > NL80211_CHAN_WIDTH_20) |
200 | ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; |
201 | else |
202 | ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; |
203 | |
204 | if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode) |
205 | return 0; |
206 | |
207 | sdata->vif.bss_conf.ht_operation_mode = ht_opmode; |
208 | sdata->u.mesh.mshcfg.ht_opmode = ht_opmode; |
209 | mpl_dbg(sdata, "selected new HT protection mode %d\n" , ht_opmode); |
210 | return BSS_CHANGED_HT; |
211 | } |
212 | |
213 | static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, |
214 | struct sta_info *sta, |
215 | enum ieee80211_self_protected_actioncode action, |
216 | u8 *da, u16 llid, u16 plid, u16 reason) |
217 | { |
218 | struct ieee80211_local *local = sdata->local; |
219 | struct sk_buff *skb; |
220 | struct ieee80211_tx_info *info; |
221 | struct ieee80211_mgmt *mgmt; |
222 | bool include_plid = false; |
223 | u16 peering_proto = 0; |
224 | u8 *pos, ie_len = 4; |
225 | u8 ie_len_he_cap, ie_len_eht_cap; |
226 | int hdr_len = offsetofend(struct ieee80211_mgmt, u.action.u.self_prot); |
227 | int err = -ENOMEM; |
228 | |
229 | ie_len_he_cap = ieee80211_ie_len_he_cap(sdata); |
230 | ie_len_eht_cap = ieee80211_ie_len_eht_cap(sdata); |
231 | skb = dev_alloc_skb(length: local->tx_headroom + |
232 | hdr_len + |
233 | 2 + /* capability info */ |
234 | 2 + /* AID */ |
235 | 2 + 8 + /* supported rates */ |
236 | 2 + (IEEE80211_MAX_SUPP_RATES - 8) + |
237 | 2 + sdata->u.mesh.mesh_id_len + |
238 | 2 + sizeof(struct ieee80211_meshconf_ie) + |
239 | 2 + sizeof(struct ieee80211_ht_cap) + |
240 | 2 + sizeof(struct ieee80211_ht_operation) + |
241 | 2 + sizeof(struct ieee80211_vht_cap) + |
242 | 2 + sizeof(struct ieee80211_vht_operation) + |
243 | ie_len_he_cap + |
244 | 2 + 1 + sizeof(struct ieee80211_he_operation) + |
245 | sizeof(struct ieee80211_he_6ghz_oper) + |
246 | 2 + 1 + sizeof(struct ieee80211_he_6ghz_capa) + |
247 | ie_len_eht_cap + |
248 | 2 + 1 + offsetof(struct ieee80211_eht_operation, optional) + |
249 | offsetof(struct ieee80211_eht_operation_info, optional) + |
250 | 2 + 8 + /* peering IE */ |
251 | sdata->u.mesh.ie_len); |
252 | if (!skb) |
253 | return err; |
254 | info = IEEE80211_SKB_CB(skb); |
255 | skb_reserve(skb, len: local->tx_headroom); |
256 | mgmt = skb_put_zero(skb, len: hdr_len); |
257 | mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | |
258 | IEEE80211_STYPE_ACTION); |
259 | memcpy(mgmt->da, da, ETH_ALEN); |
260 | memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); |
261 | memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); |
262 | mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED; |
263 | mgmt->u.action.u.self_prot.action_code = action; |
264 | |
265 | if (action != WLAN_SP_MESH_PEERING_CLOSE) { |
266 | struct ieee80211_supported_band *sband; |
267 | u32 rate_flags, basic_rates; |
268 | |
269 | sband = ieee80211_get_sband(sdata); |
270 | if (!sband) { |
271 | err = -EINVAL; |
272 | goto free; |
273 | } |
274 | |
275 | /* capability info */ |
276 | pos = skb_put_zero(skb, len: 2); |
277 | if (action == WLAN_SP_MESH_PEERING_CONFIRM) { |
278 | /* AID */ |
279 | pos = skb_put(skb, len: 2); |
280 | put_unaligned_le16(val: sta->sta.aid, p: pos); |
281 | } |
282 | |
283 | rate_flags = |
284 | ieee80211_chandef_rate_flags(chandef: &sdata->vif.bss_conf.chanreq.oper); |
285 | basic_rates = sdata->vif.bss_conf.basic_rates; |
286 | |
287 | if (ieee80211_put_srates_elem(skb, sband, basic_rates, |
288 | rate_flags, masked_rates: 0, |
289 | element_id: WLAN_EID_SUPP_RATES) || |
290 | ieee80211_put_srates_elem(skb, sband, basic_rates, |
291 | rate_flags, masked_rates: 0, |
292 | element_id: WLAN_EID_EXT_SUPP_RATES) || |
293 | mesh_add_rsn_ie(sdata, skb) || |
294 | mesh_add_meshid_ie(sdata, skb) || |
295 | mesh_add_meshconf_ie(sdata, skb)) |
296 | goto free; |
297 | } else { /* WLAN_SP_MESH_PEERING_CLOSE */ |
298 | info->flags |= IEEE80211_TX_CTL_NO_ACK; |
299 | if (mesh_add_meshid_ie(sdata, skb)) |
300 | goto free; |
301 | } |
302 | |
303 | /* Add Mesh Peering Management element */ |
304 | switch (action) { |
305 | case WLAN_SP_MESH_PEERING_OPEN: |
306 | break; |
307 | case WLAN_SP_MESH_PEERING_CONFIRM: |
308 | ie_len += 2; |
309 | include_plid = true; |
310 | break; |
311 | case WLAN_SP_MESH_PEERING_CLOSE: |
312 | if (plid) { |
313 | ie_len += 2; |
314 | include_plid = true; |
315 | } |
316 | ie_len += 2; /* reason code */ |
317 | break; |
318 | default: |
319 | err = -EINVAL; |
320 | goto free; |
321 | } |
322 | |
323 | if (WARN_ON(skb_tailroom(skb) < 2 + ie_len)) |
324 | goto free; |
325 | |
326 | pos = skb_put(skb, len: 2 + ie_len); |
327 | *pos++ = WLAN_EID_PEER_MGMT; |
328 | *pos++ = ie_len; |
329 | memcpy(pos, &peering_proto, 2); |
330 | pos += 2; |
331 | put_unaligned_le16(val: llid, p: pos); |
332 | pos += 2; |
333 | if (include_plid) { |
334 | put_unaligned_le16(val: plid, p: pos); |
335 | pos += 2; |
336 | } |
337 | if (action == WLAN_SP_MESH_PEERING_CLOSE) { |
338 | put_unaligned_le16(val: reason, p: pos); |
339 | pos += 2; |
340 | } |
341 | |
342 | if (action != WLAN_SP_MESH_PEERING_CLOSE) { |
343 | if (mesh_add_ht_cap_ie(sdata, skb) || |
344 | mesh_add_ht_oper_ie(sdata, skb) || |
345 | mesh_add_vht_cap_ie(sdata, skb) || |
346 | mesh_add_vht_oper_ie(sdata, skb) || |
347 | mesh_add_he_cap_ie(sdata, skb, ie_len: ie_len_he_cap) || |
348 | mesh_add_he_oper_ie(sdata, skb) || |
349 | mesh_add_he_6ghz_cap_ie(sdata, skb) || |
350 | mesh_add_eht_cap_ie(sdata, skb, ie_len: ie_len_eht_cap) || |
351 | mesh_add_eht_oper_ie(sdata, skb)) |
352 | goto free; |
353 | } |
354 | |
355 | if (mesh_add_vendor_ies(sdata, skb)) |
356 | goto free; |
357 | |
358 | ieee80211_tx_skb(sdata, skb); |
359 | return 0; |
360 | free: |
361 | kfree_skb(skb); |
362 | return err; |
363 | } |
364 | |
365 | /** |
366 | * __mesh_plink_deactivate - deactivate mesh peer link |
367 | * |
368 | * @sta: mesh peer link to deactivate |
369 | * |
370 | * Mesh paths with this peer as next hop should be flushed |
371 | * by the caller outside of plink_lock. |
372 | * |
373 | * Returns: beacon changed flag if the beacon content changed. |
374 | * |
375 | * Locking: the caller must hold sta->mesh->plink_lock |
376 | */ |
377 | static u64 __mesh_plink_deactivate(struct sta_info *sta) |
378 | { |
379 | struct ieee80211_sub_if_data *sdata = sta->sdata; |
380 | u64 changed = 0; |
381 | |
382 | lockdep_assert_held(&sta->mesh->plink_lock); |
383 | |
384 | if (sta->mesh->plink_state == NL80211_PLINK_ESTAB) |
385 | changed = mesh_plink_dec_estab_count(sdata); |
386 | sta->mesh->plink_state = NL80211_PLINK_BLOCKED; |
387 | |
388 | ieee80211_mps_sta_status_update(sta); |
389 | changed |= ieee80211_mps_set_sta_local_pm(sta, |
390 | pm: NL80211_MESH_POWER_UNKNOWN); |
391 | |
392 | return changed; |
393 | } |
394 | |
395 | /** |
396 | * mesh_plink_deactivate - deactivate mesh peer link |
397 | * |
398 | * @sta: mesh peer link to deactivate |
399 | * |
400 | * All mesh paths with this peer as next hop will be flushed |
401 | * |
402 | * Returns: beacon changed flag if the beacon content changed. |
403 | */ |
404 | u64 mesh_plink_deactivate(struct sta_info *sta) |
405 | { |
406 | struct ieee80211_sub_if_data *sdata = sta->sdata; |
407 | u64 changed; |
408 | |
409 | spin_lock_bh(lock: &sta->mesh->plink_lock); |
410 | changed = __mesh_plink_deactivate(sta); |
411 | |
412 | if (!sdata->u.mesh.user_mpm) { |
413 | sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED; |
414 | mesh_plink_frame_tx(sdata, sta, action: WLAN_SP_MESH_PEERING_CLOSE, |
415 | da: sta->sta.addr, llid: sta->mesh->llid, |
416 | plid: sta->mesh->plid, reason: sta->mesh->reason); |
417 | } |
418 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
419 | if (!sdata->u.mesh.user_mpm) |
420 | del_timer_sync(timer: &sta->mesh->plink_timer); |
421 | mesh_path_flush_by_nexthop(sta); |
422 | |
423 | /* make sure no readers can access nexthop sta from here on */ |
424 | synchronize_net(); |
425 | |
426 | return changed; |
427 | } |
428 | |
429 | static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata, |
430 | struct sta_info *sta, |
431 | struct ieee802_11_elems *elems) |
432 | { |
433 | struct ieee80211_local *local = sdata->local; |
434 | struct ieee80211_supported_band *sband; |
435 | u32 rates, basic_rates = 0, changed = 0; |
436 | enum ieee80211_sta_rx_bandwidth bw = sta->sta.deflink.bandwidth; |
437 | |
438 | sband = ieee80211_get_sband(sdata); |
439 | if (!sband) |
440 | return; |
441 | |
442 | rates = ieee80211_sta_get_rates(sdata, elems, band: sband->band, |
443 | basic_rates: &basic_rates); |
444 | |
445 | spin_lock_bh(lock: &sta->mesh->plink_lock); |
446 | sta->deflink.rx_stats.last_rx = jiffies; |
447 | |
448 | /* rates and capabilities don't change during peering */ |
449 | if (sta->mesh->plink_state == NL80211_PLINK_ESTAB && |
450 | sta->mesh->processed_beacon) |
451 | goto out; |
452 | sta->mesh->processed_beacon = true; |
453 | |
454 | if (sta->sta.deflink.supp_rates[sband->band] != rates) |
455 | changed |= IEEE80211_RC_SUPP_RATES_CHANGED; |
456 | sta->sta.deflink.supp_rates[sband->band] = rates; |
457 | |
458 | if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, |
459 | ht_cap_ie: elems->ht_cap_elem, |
460 | link_sta: &sta->deflink)) |
461 | changed |= IEEE80211_RC_BW_CHANGED; |
462 | |
463 | ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband, |
464 | vht_cap_ie: elems->vht_cap_elem, NULL, |
465 | link_sta: &sta->deflink); |
466 | |
467 | ieee80211_he_cap_ie_to_sta_he_cap(sdata, sband, he_cap_ie: elems->he_cap, |
468 | he_cap_len: elems->he_cap_len, |
469 | he_6ghz_capa: elems->he_6ghz_capa, |
470 | link_sta: &sta->deflink); |
471 | |
472 | ieee80211_eht_cap_ie_to_sta_eht_cap(sdata, sband, he_cap_ie: elems->he_cap, |
473 | he_cap_len: elems->he_cap_len, |
474 | eht_cap_ie_elem: elems->eht_cap, eht_cap_len: elems->eht_cap_len, |
475 | link_sta: &sta->deflink); |
476 | |
477 | if (bw != sta->sta.deflink.bandwidth) |
478 | changed |= IEEE80211_RC_BW_CHANGED; |
479 | |
480 | /* HT peer is operating 20MHz-only */ |
481 | if (elems->ht_operation && |
482 | !(elems->ht_operation->ht_param & |
483 | IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) { |
484 | if (sta->sta.deflink.bandwidth != IEEE80211_STA_RX_BW_20) |
485 | changed |= IEEE80211_RC_BW_CHANGED; |
486 | sta->sta.deflink.bandwidth = IEEE80211_STA_RX_BW_20; |
487 | } |
488 | |
489 | if (!test_sta_flag(sta, flag: WLAN_STA_RATE_CONTROL)) |
490 | rate_control_rate_init(sta); |
491 | else |
492 | rate_control_rate_update(local, sband, sta, link_id: 0, changed); |
493 | out: |
494 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
495 | } |
496 | |
497 | static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata) |
498 | { |
499 | struct sta_info *sta; |
500 | unsigned long *aid_map; |
501 | int aid; |
502 | |
503 | aid_map = bitmap_zalloc(IEEE80211_MAX_AID + 1, GFP_KERNEL); |
504 | if (!aid_map) |
505 | return -ENOMEM; |
506 | |
507 | /* reserve aid 0 for mcast indication */ |
508 | __set_bit(0, aid_map); |
509 | |
510 | rcu_read_lock(); |
511 | list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) |
512 | __set_bit(sta->sta.aid, aid_map); |
513 | rcu_read_unlock(); |
514 | |
515 | aid = find_first_zero_bit(addr: aid_map, IEEE80211_MAX_AID + 1); |
516 | bitmap_free(bitmap: aid_map); |
517 | |
518 | if (aid > IEEE80211_MAX_AID) |
519 | return -ENOBUFS; |
520 | |
521 | return aid; |
522 | } |
523 | |
524 | static struct sta_info * |
525 | __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr) |
526 | { |
527 | struct sta_info *sta; |
528 | int aid; |
529 | |
530 | if (sdata->local->num_sta >= MESH_MAX_PLINKS) |
531 | return NULL; |
532 | |
533 | aid = mesh_allocate_aid(sdata); |
534 | if (aid < 0) |
535 | return NULL; |
536 | |
537 | sta = sta_info_alloc(sdata, addr: hw_addr, GFP_KERNEL); |
538 | if (!sta) |
539 | return NULL; |
540 | |
541 | sta->mesh->plink_state = NL80211_PLINK_LISTEN; |
542 | sta->sta.wme = true; |
543 | sta->sta.aid = aid; |
544 | |
545 | sta_info_pre_move_state(sta, new_state: IEEE80211_STA_AUTH); |
546 | sta_info_pre_move_state(sta, new_state: IEEE80211_STA_ASSOC); |
547 | sta_info_pre_move_state(sta, new_state: IEEE80211_STA_AUTHORIZED); |
548 | |
549 | return sta; |
550 | } |
551 | |
552 | static struct sta_info * |
553 | mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, |
554 | struct ieee802_11_elems *elems, |
555 | struct ieee80211_rx_status *rx_status) |
556 | { |
557 | struct sta_info *sta = NULL; |
558 | |
559 | /* Userspace handles station allocation */ |
560 | if (sdata->u.mesh.user_mpm || |
561 | sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) { |
562 | if (mesh_peer_accepts_plinks(ie: elems) && |
563 | mesh_plink_availables(sdata)) { |
564 | int sig = 0; |
565 | |
566 | if (ieee80211_hw_check(&sdata->local->hw, SIGNAL_DBM)) |
567 | sig = rx_status->signal; |
568 | |
569 | cfg80211_notify_new_peer_candidate(dev: sdata->dev, macaddr: addr, |
570 | ie: elems->ie_start, |
571 | ie_len: elems->total_len, |
572 | sig_dbm: sig, GFP_KERNEL); |
573 | } |
574 | } else |
575 | sta = __mesh_sta_info_alloc(sdata, hw_addr: addr); |
576 | |
577 | return sta; |
578 | } |
579 | |
580 | /* |
581 | * mesh_sta_info_get - return mesh sta info entry for @addr. |
582 | * |
583 | * @sdata: local meshif |
584 | * @addr: peer's address |
585 | * @elems: IEs from beacon or mesh peering frame. |
586 | * @rx_status: rx status for the frame for signal reporting |
587 | * |
588 | * Return existing or newly allocated sta_info under RCU read lock. |
589 | * (re)initialize with given IEs. |
590 | */ |
591 | static struct sta_info * |
592 | mesh_sta_info_get(struct ieee80211_sub_if_data *sdata, |
593 | u8 *addr, struct ieee802_11_elems *elems, |
594 | struct ieee80211_rx_status *rx_status) __acquires(RCU) |
595 | { |
596 | struct sta_info *sta = NULL; |
597 | |
598 | rcu_read_lock(); |
599 | sta = sta_info_get(sdata, addr); |
600 | if (sta) { |
601 | mesh_sta_info_init(sdata, sta, elems); |
602 | } else { |
603 | rcu_read_unlock(); |
604 | /* can't run atomic */ |
605 | sta = mesh_sta_info_alloc(sdata, addr, elems, rx_status); |
606 | if (!sta) { |
607 | rcu_read_lock(); |
608 | return NULL; |
609 | } |
610 | |
611 | mesh_sta_info_init(sdata, sta, elems); |
612 | |
613 | if (sta_info_insert_rcu(sta)) |
614 | return NULL; |
615 | } |
616 | |
617 | return sta; |
618 | } |
619 | |
620 | /* |
621 | * mesh_neighbour_update - update or initialize new mesh neighbor. |
622 | * |
623 | * @sdata: local meshif |
624 | * @addr: peer's address |
625 | * @elems: IEs from beacon or mesh peering frame |
626 | * @rx_status: rx status for the frame for signal reporting |
627 | * |
628 | * Initiates peering if appropriate. |
629 | */ |
630 | void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, |
631 | u8 *hw_addr, |
632 | struct ieee802_11_elems *elems, |
633 | struct ieee80211_rx_status *rx_status) |
634 | { |
635 | struct sta_info *sta; |
636 | u64 changed = 0; |
637 | |
638 | sta = mesh_sta_info_get(sdata, addr: hw_addr, elems, rx_status); |
639 | if (!sta) |
640 | goto out; |
641 | |
642 | sta->mesh->connected_to_gate = elems->mesh_config->meshconf_form & |
643 | IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE; |
644 | |
645 | if (mesh_peer_accepts_plinks(ie: elems) && |
646 | sta->mesh->plink_state == NL80211_PLINK_LISTEN && |
647 | sdata->u.mesh.accepting_plinks && |
648 | sdata->u.mesh.mshcfg.auto_open_plinks && |
649 | rssi_threshold_check(sdata, sta)) |
650 | changed = mesh_plink_open(sta); |
651 | |
652 | ieee80211_mps_frame_release(sta, elems); |
653 | out: |
654 | rcu_read_unlock(); |
655 | ieee80211_mbss_info_change_notify(sdata, changed); |
656 | } |
657 | |
658 | void mesh_plink_timer(struct timer_list *t) |
659 | { |
660 | struct mesh_sta *mesh = from_timer(mesh, t, plink_timer); |
661 | struct sta_info *sta; |
662 | u16 reason = 0; |
663 | struct ieee80211_sub_if_data *sdata; |
664 | struct mesh_config *mshcfg; |
665 | enum ieee80211_self_protected_actioncode action = 0; |
666 | |
667 | /* |
668 | * This STA is valid because sta_info_destroy() will |
669 | * del_timer_sync() this timer after having made sure |
670 | * it cannot be readded (by deleting the plink.) |
671 | */ |
672 | sta = mesh->plink_sta; |
673 | |
674 | if (sta->sdata->local->quiescing) |
675 | return; |
676 | |
677 | spin_lock_bh(lock: &sta->mesh->plink_lock); |
678 | |
679 | /* If a timer fires just before a state transition on another CPU, |
680 | * we may have already extended the timeout and changed state by the |
681 | * time we've acquired the lock and arrived here. In that case, |
682 | * skip this timer and wait for the new one. |
683 | */ |
684 | if (time_before(jiffies, sta->mesh->plink_timer.expires)) { |
685 | mpl_dbg(sta->sdata, |
686 | "Ignoring timer for %pM in state %s (timer adjusted)" , |
687 | sta->sta.addr, mplstates[sta->mesh->plink_state]); |
688 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
689 | return; |
690 | } |
691 | |
692 | /* del_timer() and handler may race when entering these states */ |
693 | if (sta->mesh->plink_state == NL80211_PLINK_LISTEN || |
694 | sta->mesh->plink_state == NL80211_PLINK_ESTAB) { |
695 | mpl_dbg(sta->sdata, |
696 | "Ignoring timer for %pM in state %s (timer deleted)" , |
697 | sta->sta.addr, mplstates[sta->mesh->plink_state]); |
698 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
699 | return; |
700 | } |
701 | |
702 | mpl_dbg(sta->sdata, |
703 | "Mesh plink timer for %pM fired on state %s\n" , |
704 | sta->sta.addr, mplstates[sta->mesh->plink_state]); |
705 | sdata = sta->sdata; |
706 | mshcfg = &sdata->u.mesh.mshcfg; |
707 | |
708 | switch (sta->mesh->plink_state) { |
709 | case NL80211_PLINK_OPN_RCVD: |
710 | case NL80211_PLINK_OPN_SNT: |
711 | /* retry timer */ |
712 | if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) { |
713 | u32 rand; |
714 | mpl_dbg(sta->sdata, |
715 | "Mesh plink for %pM (retry, timeout): %d %d\n" , |
716 | sta->sta.addr, sta->mesh->plink_retries, |
717 | sta->mesh->plink_timeout); |
718 | get_random_bytes(buf: &rand, len: sizeof(u32)); |
719 | sta->mesh->plink_timeout = sta->mesh->plink_timeout + |
720 | rand % sta->mesh->plink_timeout; |
721 | ++sta->mesh->plink_retries; |
722 | mod_plink_timer(sta, sta->mesh->plink_timeout); |
723 | action = WLAN_SP_MESH_PEERING_OPEN; |
724 | break; |
725 | } |
726 | reason = WLAN_REASON_MESH_MAX_RETRIES; |
727 | fallthrough; |
728 | case NL80211_PLINK_CNF_RCVD: |
729 | /* confirm timer */ |
730 | if (!reason) |
731 | reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT; |
732 | sta->mesh->plink_state = NL80211_PLINK_HOLDING; |
733 | mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); |
734 | action = WLAN_SP_MESH_PEERING_CLOSE; |
735 | break; |
736 | case NL80211_PLINK_HOLDING: |
737 | /* holding timer */ |
738 | del_timer(timer: &sta->mesh->plink_timer); |
739 | mesh_plink_fsm_restart(sta); |
740 | break; |
741 | default: |
742 | break; |
743 | } |
744 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
745 | if (action) |
746 | mesh_plink_frame_tx(sdata, sta, action, da: sta->sta.addr, |
747 | llid: sta->mesh->llid, plid: sta->mesh->plid, reason); |
748 | } |
749 | |
750 | static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout) |
751 | { |
752 | sta->mesh->plink_timeout = timeout; |
753 | mod_timer(timer: &sta->mesh->plink_timer, expires: jiffies + msecs_to_jiffies(m: timeout)); |
754 | } |
755 | |
756 | static bool llid_in_use(struct ieee80211_sub_if_data *sdata, |
757 | u16 llid) |
758 | { |
759 | struct ieee80211_local *local = sdata->local; |
760 | bool in_use = false; |
761 | struct sta_info *sta; |
762 | |
763 | rcu_read_lock(); |
764 | list_for_each_entry_rcu(sta, &local->sta_list, list) { |
765 | if (sdata != sta->sdata) |
766 | continue; |
767 | |
768 | if (!memcmp(p: &sta->mesh->llid, q: &llid, size: sizeof(llid))) { |
769 | in_use = true; |
770 | break; |
771 | } |
772 | } |
773 | rcu_read_unlock(); |
774 | |
775 | return in_use; |
776 | } |
777 | |
778 | static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata) |
779 | { |
780 | u16 llid; |
781 | |
782 | do { |
783 | get_random_bytes(buf: &llid, len: sizeof(llid)); |
784 | } while (llid_in_use(sdata, llid)); |
785 | |
786 | return llid; |
787 | } |
788 | |
789 | u64 mesh_plink_open(struct sta_info *sta) |
790 | { |
791 | struct ieee80211_sub_if_data *sdata = sta->sdata; |
792 | u64 changed; |
793 | |
794 | if (!test_sta_flag(sta, flag: WLAN_STA_AUTH)) |
795 | return 0; |
796 | |
797 | spin_lock_bh(lock: &sta->mesh->plink_lock); |
798 | sta->mesh->llid = mesh_get_new_llid(sdata); |
799 | if (sta->mesh->plink_state != NL80211_PLINK_LISTEN && |
800 | sta->mesh->plink_state != NL80211_PLINK_BLOCKED) { |
801 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
802 | return 0; |
803 | } |
804 | sta->mesh->plink_state = NL80211_PLINK_OPN_SNT; |
805 | mesh_plink_timer_set(sta, timeout: sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); |
806 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
807 | mpl_dbg(sdata, |
808 | "Mesh plink: starting establishment with %pM\n" , |
809 | sta->sta.addr); |
810 | |
811 | /* set the non-peer mode to active during peering */ |
812 | changed = ieee80211_mps_local_status_update(sdata); |
813 | |
814 | mesh_plink_frame_tx(sdata, sta, action: WLAN_SP_MESH_PEERING_OPEN, |
815 | da: sta->sta.addr, llid: sta->mesh->llid, plid: 0, reason: 0); |
816 | return changed; |
817 | } |
818 | |
819 | u64 mesh_plink_block(struct sta_info *sta) |
820 | { |
821 | u64 changed; |
822 | |
823 | spin_lock_bh(lock: &sta->mesh->plink_lock); |
824 | changed = __mesh_plink_deactivate(sta); |
825 | sta->mesh->plink_state = NL80211_PLINK_BLOCKED; |
826 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
827 | mesh_path_flush_by_nexthop(sta); |
828 | |
829 | return changed; |
830 | } |
831 | |
832 | static void mesh_plink_close(struct ieee80211_sub_if_data *sdata, |
833 | struct sta_info *sta, |
834 | enum plink_event event) |
835 | { |
836 | struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; |
837 | u16 reason = (event == CLS_ACPT) ? |
838 | WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG; |
839 | |
840 | sta->mesh->reason = reason; |
841 | sta->mesh->plink_state = NL80211_PLINK_HOLDING; |
842 | mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); |
843 | } |
844 | |
845 | static u64 mesh_plink_establish(struct ieee80211_sub_if_data *sdata, |
846 | struct sta_info *sta) |
847 | { |
848 | struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; |
849 | u64 changed = 0; |
850 | |
851 | del_timer(timer: &sta->mesh->plink_timer); |
852 | sta->mesh->plink_state = NL80211_PLINK_ESTAB; |
853 | changed |= mesh_plink_inc_estab_count(sdata); |
854 | changed |= mesh_set_ht_prot_mode(sdata); |
855 | changed |= mesh_set_short_slot_time(sdata); |
856 | mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n" , sta->sta.addr); |
857 | ieee80211_mps_sta_status_update(sta); |
858 | changed |= ieee80211_mps_set_sta_local_pm(sta, pm: mshcfg->power_mode); |
859 | return changed; |
860 | } |
861 | |
862 | /** |
863 | * mesh_plink_fsm - step @sta MPM based on @event |
864 | * |
865 | * @sdata: interface |
866 | * @sta: mesh neighbor |
867 | * @event: peering event |
868 | * |
869 | * Return: changed MBSS flags |
870 | */ |
871 | static u64 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata, |
872 | struct sta_info *sta, enum plink_event event) |
873 | { |
874 | struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; |
875 | enum ieee80211_self_protected_actioncode action = 0; |
876 | u64 changed = 0; |
877 | bool flush = false; |
878 | |
879 | mpl_dbg(sdata, "peer %pM in state %s got event %s\n" , sta->sta.addr, |
880 | mplstates[sta->mesh->plink_state], mplevents[event]); |
881 | |
882 | spin_lock_bh(lock: &sta->mesh->plink_lock); |
883 | switch (sta->mesh->plink_state) { |
884 | case NL80211_PLINK_LISTEN: |
885 | switch (event) { |
886 | case CLS_ACPT: |
887 | mesh_plink_fsm_restart(sta); |
888 | break; |
889 | case OPN_ACPT: |
890 | sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD; |
891 | sta->mesh->llid = mesh_get_new_llid(sdata); |
892 | mesh_plink_timer_set(sta, |
893 | timeout: mshcfg->dot11MeshRetryTimeout); |
894 | |
895 | /* set the non-peer mode to active during peering */ |
896 | changed |= ieee80211_mps_local_status_update(sdata); |
897 | action = WLAN_SP_MESH_PEERING_OPEN; |
898 | break; |
899 | default: |
900 | break; |
901 | } |
902 | break; |
903 | case NL80211_PLINK_OPN_SNT: |
904 | switch (event) { |
905 | case OPN_RJCT: |
906 | case CNF_RJCT: |
907 | case CLS_ACPT: |
908 | mesh_plink_close(sdata, sta, event); |
909 | action = WLAN_SP_MESH_PEERING_CLOSE; |
910 | break; |
911 | case OPN_ACPT: |
912 | /* retry timer is left untouched */ |
913 | sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD; |
914 | action = WLAN_SP_MESH_PEERING_CONFIRM; |
915 | break; |
916 | case CNF_ACPT: |
917 | sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD; |
918 | mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout); |
919 | break; |
920 | default: |
921 | break; |
922 | } |
923 | break; |
924 | case NL80211_PLINK_OPN_RCVD: |
925 | switch (event) { |
926 | case OPN_RJCT: |
927 | case CNF_RJCT: |
928 | case CLS_ACPT: |
929 | mesh_plink_close(sdata, sta, event); |
930 | action = WLAN_SP_MESH_PEERING_CLOSE; |
931 | break; |
932 | case OPN_ACPT: |
933 | action = WLAN_SP_MESH_PEERING_CONFIRM; |
934 | break; |
935 | case CNF_ACPT: |
936 | changed |= mesh_plink_establish(sdata, sta); |
937 | break; |
938 | default: |
939 | break; |
940 | } |
941 | break; |
942 | case NL80211_PLINK_CNF_RCVD: |
943 | switch (event) { |
944 | case OPN_RJCT: |
945 | case CNF_RJCT: |
946 | case CLS_ACPT: |
947 | mesh_plink_close(sdata, sta, event); |
948 | action = WLAN_SP_MESH_PEERING_CLOSE; |
949 | break; |
950 | case OPN_ACPT: |
951 | changed |= mesh_plink_establish(sdata, sta); |
952 | action = WLAN_SP_MESH_PEERING_CONFIRM; |
953 | break; |
954 | default: |
955 | break; |
956 | } |
957 | break; |
958 | case NL80211_PLINK_ESTAB: |
959 | switch (event) { |
960 | case CLS_ACPT: |
961 | changed |= __mesh_plink_deactivate(sta); |
962 | changed |= mesh_set_ht_prot_mode(sdata); |
963 | changed |= mesh_set_short_slot_time(sdata); |
964 | mesh_plink_close(sdata, sta, event); |
965 | action = WLAN_SP_MESH_PEERING_CLOSE; |
966 | flush = true; |
967 | break; |
968 | case OPN_ACPT: |
969 | action = WLAN_SP_MESH_PEERING_CONFIRM; |
970 | break; |
971 | default: |
972 | break; |
973 | } |
974 | break; |
975 | case NL80211_PLINK_HOLDING: |
976 | switch (event) { |
977 | case CLS_ACPT: |
978 | del_timer(timer: &sta->mesh->plink_timer); |
979 | mesh_plink_fsm_restart(sta); |
980 | break; |
981 | case OPN_ACPT: |
982 | case CNF_ACPT: |
983 | case OPN_RJCT: |
984 | case CNF_RJCT: |
985 | action = WLAN_SP_MESH_PEERING_CLOSE; |
986 | break; |
987 | default: |
988 | break; |
989 | } |
990 | break; |
991 | default: |
992 | /* should not get here, PLINK_BLOCKED is dealt with at the |
993 | * beginning of the function |
994 | */ |
995 | break; |
996 | } |
997 | spin_unlock_bh(lock: &sta->mesh->plink_lock); |
998 | if (flush) |
999 | mesh_path_flush_by_nexthop(sta); |
1000 | if (action) { |
1001 | mesh_plink_frame_tx(sdata, sta, action, da: sta->sta.addr, |
1002 | llid: sta->mesh->llid, plid: sta->mesh->plid, |
1003 | reason: sta->mesh->reason); |
1004 | |
1005 | /* also send confirm in open case */ |
1006 | if (action == WLAN_SP_MESH_PEERING_OPEN) { |
1007 | mesh_plink_frame_tx(sdata, sta, |
1008 | action: WLAN_SP_MESH_PEERING_CONFIRM, |
1009 | da: sta->sta.addr, llid: sta->mesh->llid, |
1010 | plid: sta->mesh->plid, reason: 0); |
1011 | } |
1012 | } |
1013 | |
1014 | return changed; |
1015 | } |
1016 | |
1017 | /* |
1018 | * mesh_plink_get_event - get correct MPM event |
1019 | * |
1020 | * @sdata: interface |
1021 | * @sta: peer, leave NULL if processing a frame from a new suitable peer |
1022 | * @elems: peering management IEs |
1023 | * @ftype: frame type |
1024 | * @llid: peer's peer link ID |
1025 | * @plid: peer's local link ID |
1026 | * |
1027 | * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as |
1028 | * an error. |
1029 | */ |
1030 | static enum plink_event |
1031 | mesh_plink_get_event(struct ieee80211_sub_if_data *sdata, |
1032 | struct sta_info *sta, |
1033 | struct ieee802_11_elems *elems, |
1034 | enum ieee80211_self_protected_actioncode ftype, |
1035 | u16 llid, u16 plid) |
1036 | { |
1037 | enum plink_event event = PLINK_UNDEFINED; |
1038 | u8 ie_len = elems->peering_len; |
1039 | bool matches_local; |
1040 | |
1041 | matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE || |
1042 | mesh_matches_local(sdata, ie: elems)); |
1043 | |
1044 | /* deny open request from non-matching peer */ |
1045 | if (!matches_local && !sta) { |
1046 | event = OPN_RJCT; |
1047 | goto out; |
1048 | } |
1049 | |
1050 | if (!sta) { |
1051 | if (ftype != WLAN_SP_MESH_PEERING_OPEN) { |
1052 | mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n" ); |
1053 | goto out; |
1054 | } |
1055 | /* ftype == WLAN_SP_MESH_PEERING_OPEN */ |
1056 | if (!mesh_plink_free_count(sdata)) { |
1057 | mpl_dbg(sdata, "Mesh plink error: no more free plinks\n" ); |
1058 | goto out; |
1059 | } |
1060 | |
1061 | /* new matching peer */ |
1062 | event = OPN_ACPT; |
1063 | goto out; |
1064 | } else { |
1065 | if (!test_sta_flag(sta, flag: WLAN_STA_AUTH)) { |
1066 | mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n" ); |
1067 | goto out; |
1068 | } |
1069 | if (sta->mesh->plink_state == NL80211_PLINK_BLOCKED) |
1070 | goto out; |
1071 | } |
1072 | |
1073 | switch (ftype) { |
1074 | case WLAN_SP_MESH_PEERING_OPEN: |
1075 | if (!matches_local) |
1076 | event = OPN_RJCT; |
1077 | else if (!mesh_plink_free_count(sdata) || |
1078 | (sta->mesh->plid && sta->mesh->plid != plid)) |
1079 | event = OPN_IGNR; |
1080 | else |
1081 | event = OPN_ACPT; |
1082 | break; |
1083 | case WLAN_SP_MESH_PEERING_CONFIRM: |
1084 | if (!matches_local) |
1085 | event = CNF_RJCT; |
1086 | else if (!mesh_plink_free_count(sdata) || |
1087 | sta->mesh->llid != llid || |
1088 | (sta->mesh->plid && sta->mesh->plid != plid)) |
1089 | event = CNF_IGNR; |
1090 | else |
1091 | event = CNF_ACPT; |
1092 | break; |
1093 | case WLAN_SP_MESH_PEERING_CLOSE: |
1094 | if (sta->mesh->plink_state == NL80211_PLINK_ESTAB) |
1095 | /* Do not check for llid or plid. This does not |
1096 | * follow the standard but since multiple plinks |
1097 | * per sta are not supported, it is necessary in |
1098 | * order to avoid a livelock when MP A sees an |
1099 | * establish peer link to MP B but MP B does not |
1100 | * see it. This can be caused by a timeout in |
1101 | * B's peer link establishment or B beign |
1102 | * restarted. |
1103 | */ |
1104 | event = CLS_ACPT; |
1105 | else if (sta->mesh->plid != plid) |
1106 | event = CLS_IGNR; |
1107 | else if (ie_len == 8 && sta->mesh->llid != llid) |
1108 | event = CLS_IGNR; |
1109 | else |
1110 | event = CLS_ACPT; |
1111 | break; |
1112 | default: |
1113 | mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n" ); |
1114 | break; |
1115 | } |
1116 | |
1117 | out: |
1118 | return event; |
1119 | } |
1120 | |
1121 | static void |
1122 | mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata, |
1123 | struct ieee80211_mgmt *mgmt, |
1124 | struct ieee802_11_elems *elems, |
1125 | struct ieee80211_rx_status *rx_status) |
1126 | { |
1127 | |
1128 | struct sta_info *sta; |
1129 | enum plink_event event; |
1130 | enum ieee80211_self_protected_actioncode ftype; |
1131 | u64 changed = 0; |
1132 | u8 ie_len = elems->peering_len; |
1133 | u16 plid, llid = 0; |
1134 | |
1135 | if (!elems->peering) { |
1136 | mpl_dbg(sdata, |
1137 | "Mesh plink: missing necessary peer link ie\n" ); |
1138 | return; |
1139 | } |
1140 | |
1141 | if (elems->rsn_len && |
1142 | sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { |
1143 | mpl_dbg(sdata, |
1144 | "Mesh plink: can't establish link with secure peer\n" ); |
1145 | return; |
1146 | } |
1147 | |
1148 | ftype = mgmt->u.action.u.self_prot.action_code; |
1149 | if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || |
1150 | (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || |
1151 | (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 |
1152 | && ie_len != 8)) { |
1153 | mpl_dbg(sdata, |
1154 | "Mesh plink: incorrect plink ie length %d %d\n" , |
1155 | ftype, ie_len); |
1156 | return; |
1157 | } |
1158 | |
1159 | if (ftype != WLAN_SP_MESH_PEERING_CLOSE && |
1160 | (!elems->mesh_id || !elems->mesh_config)) { |
1161 | mpl_dbg(sdata, "Mesh plink: missing necessary ie\n" ); |
1162 | return; |
1163 | } |
1164 | /* Note the lines below are correct, the llid in the frame is the plid |
1165 | * from the point of view of this host. |
1166 | */ |
1167 | plid = get_unaligned_le16(PLINK_GET_LLID(elems->peering)); |
1168 | if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || |
1169 | (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) |
1170 | llid = get_unaligned_le16(PLINK_GET_PLID(elems->peering)); |
1171 | |
1172 | /* WARNING: Only for sta pointer, is dropped & re-acquired */ |
1173 | rcu_read_lock(); |
1174 | |
1175 | sta = sta_info_get(sdata, addr: mgmt->sa); |
1176 | |
1177 | if (ftype == WLAN_SP_MESH_PEERING_OPEN && |
1178 | !rssi_threshold_check(sdata, sta)) { |
1179 | mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n" , |
1180 | mgmt->sa); |
1181 | goto unlock_rcu; |
1182 | } |
1183 | |
1184 | /* Now we will figure out the appropriate event... */ |
1185 | event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid); |
1186 | |
1187 | if (event == OPN_ACPT) { |
1188 | rcu_read_unlock(); |
1189 | /* allocate sta entry if necessary and update info */ |
1190 | sta = mesh_sta_info_get(sdata, addr: mgmt->sa, elems, rx_status); |
1191 | if (!sta) { |
1192 | mpl_dbg(sdata, "Mesh plink: failed to init peer!\n" ); |
1193 | goto unlock_rcu; |
1194 | } |
1195 | sta->mesh->plid = plid; |
1196 | } else if (!sta && event == OPN_RJCT) { |
1197 | mesh_plink_frame_tx(sdata, NULL, action: WLAN_SP_MESH_PEERING_CLOSE, |
1198 | da: mgmt->sa, llid: 0, plid, |
1199 | reason: WLAN_REASON_MESH_CONFIG); |
1200 | goto unlock_rcu; |
1201 | } else if (!sta || event == PLINK_UNDEFINED) { |
1202 | /* something went wrong */ |
1203 | goto unlock_rcu; |
1204 | } |
1205 | |
1206 | if (event == CNF_ACPT) { |
1207 | /* 802.11-2012 13.3.7.2 - update plid on CNF if not set */ |
1208 | if (!sta->mesh->plid) |
1209 | sta->mesh->plid = plid; |
1210 | |
1211 | sta->mesh->aid = get_unaligned_le16(PLINK_CNF_AID(mgmt)); |
1212 | } |
1213 | |
1214 | changed |= mesh_plink_fsm(sdata, sta, event); |
1215 | |
1216 | unlock_rcu: |
1217 | rcu_read_unlock(); |
1218 | |
1219 | if (changed) |
1220 | ieee80211_mbss_info_change_notify(sdata, changed); |
1221 | } |
1222 | |
1223 | void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, |
1224 | struct ieee80211_mgmt *mgmt, size_t len, |
1225 | struct ieee80211_rx_status *rx_status) |
1226 | { |
1227 | struct ieee802_11_elems *elems; |
1228 | size_t baselen; |
1229 | u8 *baseaddr; |
1230 | |
1231 | /* need action_code, aux */ |
1232 | if (len < IEEE80211_MIN_ACTION_SIZE + 3) |
1233 | return; |
1234 | |
1235 | if (sdata->u.mesh.user_mpm) |
1236 | /* userspace must register for these */ |
1237 | return; |
1238 | |
1239 | if (is_multicast_ether_addr(addr: mgmt->da)) { |
1240 | mpl_dbg(sdata, |
1241 | "Mesh plink: ignore frame from multicast address\n" ); |
1242 | return; |
1243 | } |
1244 | |
1245 | baseaddr = mgmt->u.action.u.self_prot.variable; |
1246 | baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; |
1247 | if (mgmt->u.action.u.self_prot.action_code == |
1248 | WLAN_SP_MESH_PEERING_CONFIRM) { |
1249 | baseaddr += 4; |
1250 | baselen += 4; |
1251 | |
1252 | if (baselen > len) |
1253 | return; |
1254 | } |
1255 | elems = ieee802_11_parse_elems(start: baseaddr, len: len - baselen, action: true, NULL); |
1256 | if (elems) { |
1257 | mesh_process_plink_frame(sdata, mgmt, elems, rx_status); |
1258 | kfree(objp: elems); |
1259 | } |
1260 | } |
1261 | |