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1 /*
2 * HT handling
3 *
4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
5 * Copyright 2002-2005, Instant802 Networks, Inc.
6 * Copyright 2005-2006, Devicescape Software, Inc.
7 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9 * Copyright 2007-2010, Intel Corporation
10 * Copyright 2017 Intel Deutschland GmbH
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 */
16
17 #include <linux/ieee80211.h>
18 #include <linux/export.h>
19 #include <net/mac80211.h>
20 #include "ieee80211_i.h"
21 #include "rate.h"
22
23 static void __check_htcap_disable(struct ieee80211_ht_cap *ht_capa,
24 struct ieee80211_ht_cap *ht_capa_mask,
25 struct ieee80211_sta_ht_cap *ht_cap,
26 u16 flag)
27 {
28 __le16 le_flag = cpu_to_le16(flag);
29 if (ht_capa_mask->cap_info & le_flag) {
30 if (!(ht_capa->cap_info & le_flag))
31 ht_cap->cap &= ~flag;
32 }
33 }
34
35 static void __check_htcap_enable(struct ieee80211_ht_cap *ht_capa,
36 struct ieee80211_ht_cap *ht_capa_mask,
37 struct ieee80211_sta_ht_cap *ht_cap,
38 u16 flag)
39 {
40 __le16 le_flag = cpu_to_le16(flag);
41
42 if ((ht_capa_mask->cap_info & le_flag) &&
43 (ht_capa->cap_info & le_flag))
44 ht_cap->cap |= flag;
45 }
46
47 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
48 struct ieee80211_sta_ht_cap *ht_cap)
49 {
50 struct ieee80211_ht_cap *ht_capa, *ht_capa_mask;
51 u8 *scaps, *smask;
52 int i;
53
54 if (!ht_cap->ht_supported)
55 return;
56
57 switch (sdata->vif.type) {
58 case NL80211_IFTYPE_STATION:
59 ht_capa = &sdata->u.mgd.ht_capa;
60 ht_capa_mask = &sdata->u.mgd.ht_capa_mask;
61 break;
62 case NL80211_IFTYPE_ADHOC:
63 ht_capa = &sdata->u.ibss.ht_capa;
64 ht_capa_mask = &sdata->u.ibss.ht_capa_mask;
65 break;
66 default:
67 WARN_ON_ONCE(1);
68 return;
69 }
70
71 scaps = (u8 *)(&ht_capa->mcs.rx_mask);
72 smask = (u8 *)(&ht_capa_mask->mcs.rx_mask);
73
74 /* NOTE: If you add more over-rides here, update register_hw
75 * ht_capa_mod_mask logic in main.c as well.
76 * And, if this method can ever change ht_cap.ht_supported, fix
77 * the check in ieee80211_add_ht_ie.
78 */
79
80 /* check for HT over-rides, MCS rates first. */
81 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
82 u8 m = smask[i];
83 ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
84 /* Add back rates that are supported */
85 ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
86 }
87
88 /* Force removal of HT-40 capabilities? */
89 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
90 IEEE80211_HT_CAP_SUP_WIDTH_20_40);
91 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
92 IEEE80211_HT_CAP_SGI_40);
93
94 /* Allow user to disable SGI-20 (SGI-40 is handled above) */
95 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
96 IEEE80211_HT_CAP_SGI_20);
97
98 /* Allow user to disable the max-AMSDU bit. */
99 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
100 IEEE80211_HT_CAP_MAX_AMSDU);
101
102 /* Allow user to disable LDPC */
103 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
104 IEEE80211_HT_CAP_LDPC_CODING);
105
106 /* Allow user to enable 40 MHz intolerant bit. */
107 __check_htcap_enable(ht_capa, ht_capa_mask, ht_cap,
108 IEEE80211_HT_CAP_40MHZ_INTOLERANT);
109
110 /* Allow user to decrease AMPDU factor */
111 if (ht_capa_mask->ampdu_params_info &
112 IEEE80211_HT_AMPDU_PARM_FACTOR) {
113 u8 n = ht_capa->ampdu_params_info &
114 IEEE80211_HT_AMPDU_PARM_FACTOR;
115 if (n < ht_cap->ampdu_factor)
116 ht_cap->ampdu_factor = n;
117 }
118
119 /* Allow the user to increase AMPDU density. */
120 if (ht_capa_mask->ampdu_params_info &
121 IEEE80211_HT_AMPDU_PARM_DENSITY) {
122 u8 n = (ht_capa->ampdu_params_info &
123 IEEE80211_HT_AMPDU_PARM_DENSITY)
124 >> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
125 if (n > ht_cap->ampdu_density)
126 ht_cap->ampdu_density = n;
127 }
128 }
129
130
131 bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
132 struct ieee80211_supported_band *sband,
133 const struct ieee80211_ht_cap *ht_cap_ie,
134 struct sta_info *sta)
135 {
136 struct ieee80211_sta_ht_cap ht_cap, own_cap;
137 u8 ampdu_info, tx_mcs_set_cap;
138 int i, max_tx_streams;
139 bool changed;
140 enum ieee80211_sta_rx_bandwidth bw;
141 enum ieee80211_smps_mode smps_mode;
142
143 memset(&ht_cap, 0, sizeof(ht_cap));
144
145 if (!ht_cap_ie || !sband->ht_cap.ht_supported)
146 goto apply;
147
148 ht_cap.ht_supported = true;
149
150 own_cap = sband->ht_cap;
151
152 /*
153 * If user has specified capability over-rides, take care
154 * of that if the station we're setting up is the AP or TDLS peer that
155 * we advertised a restricted capability set to. Override
156 * our own capabilities and then use those below.
157 */
158 if (sdata->vif.type == NL80211_IFTYPE_STATION ||
159 sdata->vif.type == NL80211_IFTYPE_ADHOC)
160 ieee80211_apply_htcap_overrides(sdata, &own_cap);
161
162 /*
163 * The bits listed in this expression should be
164 * the same for the peer and us, if the station
165 * advertises more then we can't use those thus
166 * we mask them out.
167 */
168 ht_cap.cap = le16_to_cpu(ht_cap_ie->cap_info) &
169 (own_cap.cap | ~(IEEE80211_HT_CAP_LDPC_CODING |
170 IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
171 IEEE80211_HT_CAP_GRN_FLD |
172 IEEE80211_HT_CAP_SGI_20 |
173 IEEE80211_HT_CAP_SGI_40 |
174 IEEE80211_HT_CAP_DSSSCCK40));
175
176 /*
177 * The STBC bits are asymmetric -- if we don't have
178 * TX then mask out the peer's RX and vice versa.
179 */
180 if (!(own_cap.cap & IEEE80211_HT_CAP_TX_STBC))
181 ht_cap.cap &= ~IEEE80211_HT_CAP_RX_STBC;
182 if (!(own_cap.cap & IEEE80211_HT_CAP_RX_STBC))
183 ht_cap.cap &= ~IEEE80211_HT_CAP_TX_STBC;
184
185 ampdu_info = ht_cap_ie->ampdu_params_info;
186 ht_cap.ampdu_factor =
187 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
188 ht_cap.ampdu_density =
189 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
190
191 /* own MCS TX capabilities */
192 tx_mcs_set_cap = own_cap.mcs.tx_params;
193
194 /* Copy peer MCS TX capabilities, the driver might need them. */
195 ht_cap.mcs.tx_params = ht_cap_ie->mcs.tx_params;
196
197 /* can we TX with MCS rates? */
198 if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
199 goto apply;
200
201 /* Counting from 0, therefore +1 */
202 if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
203 max_tx_streams =
204 ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
205 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
206 else
207 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
208
209 /*
210 * 802.11n-2009 20.3.5 / 20.6 says:
211 * - indices 0 to 7 and 32 are single spatial stream
212 * - 8 to 31 are multiple spatial streams using equal modulation
213 * [8..15 for two streams, 16..23 for three and 24..31 for four]
214 * - remainder are multiple spatial streams using unequal modulation
215 */
216 for (i = 0; i < max_tx_streams; i++)
217 ht_cap.mcs.rx_mask[i] =
218 own_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
219
220 if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
221 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
222 i < IEEE80211_HT_MCS_MASK_LEN; i++)
223 ht_cap.mcs.rx_mask[i] =
224 own_cap.mcs.rx_mask[i] &
225 ht_cap_ie->mcs.rx_mask[i];
226
227 /* handle MCS rate 32 too */
228 if (own_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
229 ht_cap.mcs.rx_mask[32/8] |= 1;
230
231 /* set Rx highest rate */
232 ht_cap.mcs.rx_highest = ht_cap_ie->mcs.rx_highest;
233
234 if (ht_cap.cap & IEEE80211_HT_CAP_MAX_AMSDU)
235 sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_7935;
236 else
237 sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_3839;
238
239 apply:
240 changed = memcmp(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
241
242 memcpy(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
243
244 switch (sdata->vif.bss_conf.chandef.width) {
245 default:
246 WARN_ON_ONCE(1);
247 /* fall through */
248 case NL80211_CHAN_WIDTH_20_NOHT:
249 case NL80211_CHAN_WIDTH_20:
250 bw = IEEE80211_STA_RX_BW_20;
251 break;
252 case NL80211_CHAN_WIDTH_40:
253 case NL80211_CHAN_WIDTH_80:
254 case NL80211_CHAN_WIDTH_80P80:
255 case NL80211_CHAN_WIDTH_160:
256 bw = ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
257 IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
258 break;
259 }
260
261 sta->sta.bandwidth = bw;
262
263 sta->cur_max_bandwidth =
264 ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
265 IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
266
267 switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS)
268 >> IEEE80211_HT_CAP_SM_PS_SHIFT) {
269 case WLAN_HT_CAP_SM_PS_INVALID:
270 case WLAN_HT_CAP_SM_PS_STATIC:
271 smps_mode = IEEE80211_SMPS_STATIC;
272 break;
273 case WLAN_HT_CAP_SM_PS_DYNAMIC:
274 smps_mode = IEEE80211_SMPS_DYNAMIC;
275 break;
276 case WLAN_HT_CAP_SM_PS_DISABLED:
277 smps_mode = IEEE80211_SMPS_OFF;
278 break;
279 }
280
281 if (smps_mode != sta->sta.smps_mode)
282 changed = true;
283 sta->sta.smps_mode = smps_mode;
284
285 return changed;
286 }
287
288 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
289 enum ieee80211_agg_stop_reason reason)
290 {
291 int i;
292
293 for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
294 __ieee80211_stop_tx_ba_session(sta, i, reason);
295 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
296 WLAN_REASON_QSTA_LEAVE_QBSS,
297 reason != AGG_STOP_DESTROY_STA &&
298 reason != AGG_STOP_PEER_REQUEST);
299 }
300
301 /* stopping might queue the work again - so cancel only afterwards */
302 cancel_work_sync(&sta->ampdu_mlme.work);
303 }
304
305 void ieee80211_ba_session_work(struct work_struct *work)
306 {
307 struct sta_info *sta =
308 container_of(work, struct sta_info, ampdu_mlme.work);
309 struct tid_ampdu_tx *tid_tx;
310 int tid;
311
312 /*
313 * When this flag is set, new sessions should be
314 * blocked, and existing sessions will be torn
315 * down by the code that set the flag, so this
316 * need not run.
317 */
318 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA))
319 return;
320
321 mutex_lock(&sta->ampdu_mlme.mtx);
322 for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
323 if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
324 ___ieee80211_stop_rx_ba_session(
325 sta, tid, WLAN_BACK_RECIPIENT,
326 WLAN_REASON_QSTA_TIMEOUT, true);
327
328 if (test_and_clear_bit(tid,
329 sta->ampdu_mlme.tid_rx_stop_requested))
330 ___ieee80211_stop_rx_ba_session(
331 sta, tid, WLAN_BACK_RECIPIENT,
332 WLAN_REASON_UNSPECIFIED, true);
333
334 spin_lock_bh(&sta->lock);
335
336 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
337 if (tid_tx) {
338 /*
339 * Assign it over to the normal tid_tx array
340 * where it "goes live".
341 */
342
343 sta->ampdu_mlme.tid_start_tx[tid] = NULL;
344 /* could there be a race? */
345 if (sta->ampdu_mlme.tid_tx[tid])
346 kfree(tid_tx);
347 else
348 ieee80211_assign_tid_tx(sta, tid, tid_tx);
349 spin_unlock_bh(&sta->lock);
350
351 ieee80211_tx_ba_session_handle_start(sta, tid);
352 continue;
353 }
354 spin_unlock_bh(&sta->lock);
355
356 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
357 if (!tid_tx)
358 continue;
359
360 if (test_and_clear_bit(HT_AGG_STATE_START_CB, &tid_tx->state))
361 ieee80211_start_tx_ba_cb(sta, tid, tid_tx);
362 if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
363 ___ieee80211_stop_tx_ba_session(sta, tid,
364 AGG_STOP_LOCAL_REQUEST);
365 if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
366 ieee80211_stop_tx_ba_cb(sta, tid, tid_tx);
367 }
368 mutex_unlock(&sta->ampdu_mlme.mtx);
369 }
370
371 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
372 const u8 *da, u16 tid,
373 u16 initiator, u16 reason_code)
374 {
375 struct ieee80211_local *local = sdata->local;
376 struct sk_buff *skb;
377 struct ieee80211_mgmt *mgmt;
378 u16 params;
379
380 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
381 if (!skb)
382 return;
383
384 skb_reserve(skb, local->hw.extra_tx_headroom);
385 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
386 memset(mgmt, 0, 24);
387 memcpy(mgmt->da, da, ETH_ALEN);
388 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
389 if (sdata->vif.type == NL80211_IFTYPE_AP ||
390 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
391 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
392 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
393 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
394 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
395 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
396 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
397
398 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
399 IEEE80211_STYPE_ACTION);
400
401 skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
402
403 mgmt->u.action.category = WLAN_CATEGORY_BACK;
404 mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
405 params = (u16)(initiator << 11); /* bit 11 initiator */
406 params |= (u16)(tid << 12); /* bit 15:12 TID number */
407
408 mgmt->u.action.u.delba.params = cpu_to_le16(params);
409 mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
410
411 ieee80211_tx_skb(sdata, skb);
412 }
413
414 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
415 struct sta_info *sta,
416 struct ieee80211_mgmt *mgmt, size_t len)
417 {
418 u16 tid, params;
419 u16 initiator;
420
421 params = le16_to_cpu(mgmt->u.action.u.delba.params);
422 tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
423 initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
424
425 ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n",
426 mgmt->sa, initiator ? "initiator" : "recipient",
427 tid,
428 le16_to_cpu(mgmt->u.action.u.delba.reason_code));
429
430 if (initiator == WLAN_BACK_INITIATOR)
431 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
432 true);
433 else
434 __ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
435 }
436
437 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
438 enum ieee80211_smps_mode smps, const u8 *da,
439 const u8 *bssid)
440 {
441 struct ieee80211_local *local = sdata->local;
442 struct sk_buff *skb;
443 struct ieee80211_mgmt *action_frame;
444
445 /* 27 = header + category + action + smps mode */
446 skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
447 if (!skb)
448 return -ENOMEM;
449
450 skb_reserve(skb, local->hw.extra_tx_headroom);
451 action_frame = (void *)skb_put(skb, 27);
452 memcpy(action_frame->da, da, ETH_ALEN);
453 memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
454 memcpy(action_frame->bssid, bssid, ETH_ALEN);
455 action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
456 IEEE80211_STYPE_ACTION);
457 action_frame->u.action.category = WLAN_CATEGORY_HT;
458 action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
459 switch (smps) {
460 case IEEE80211_SMPS_AUTOMATIC:
461 case IEEE80211_SMPS_NUM_MODES:
462 WARN_ON(1);
463 case IEEE80211_SMPS_OFF:
464 action_frame->u.action.u.ht_smps.smps_control =
465 WLAN_HT_SMPS_CONTROL_DISABLED;
466 break;
467 case IEEE80211_SMPS_STATIC:
468 action_frame->u.action.u.ht_smps.smps_control =
469 WLAN_HT_SMPS_CONTROL_STATIC;
470 break;
471 case IEEE80211_SMPS_DYNAMIC:
472 action_frame->u.action.u.ht_smps.smps_control =
473 WLAN_HT_SMPS_CONTROL_DYNAMIC;
474 break;
475 }
476
477 /* we'll do more on status of this frame */
478 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
479 ieee80211_tx_skb(sdata, skb);
480
481 return 0;
482 }
483
484 void ieee80211_request_smps_mgd_work(struct work_struct *work)
485 {
486 struct ieee80211_sub_if_data *sdata =
487 container_of(work, struct ieee80211_sub_if_data,
488 u.mgd.request_smps_work);
489
490 sdata_lock(sdata);
491 __ieee80211_request_smps_mgd(sdata, sdata->u.mgd.driver_smps_mode);
492 sdata_unlock(sdata);
493 }
494
495 void ieee80211_request_smps_ap_work(struct work_struct *work)
496 {
497 struct ieee80211_sub_if_data *sdata =
498 container_of(work, struct ieee80211_sub_if_data,
499 u.ap.request_smps_work);
500
501 sdata_lock(sdata);
502 if (sdata_dereference(sdata->u.ap.beacon, sdata))
503 __ieee80211_request_smps_ap(sdata,
504 sdata->u.ap.driver_smps_mode);
505 sdata_unlock(sdata);
506 }
507
508 void ieee80211_request_smps(struct ieee80211_vif *vif,
509 enum ieee80211_smps_mode smps_mode)
510 {
511 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
512
513 if (WARN_ON_ONCE(vif->type != NL80211_IFTYPE_STATION &&
514 vif->type != NL80211_IFTYPE_AP))
515 return;
516
517 if (vif->type == NL80211_IFTYPE_STATION) {
518 if (sdata->u.mgd.driver_smps_mode == smps_mode)
519 return;
520 sdata->u.mgd.driver_smps_mode = smps_mode;
521 ieee80211_queue_work(&sdata->local->hw,
522 &sdata->u.mgd.request_smps_work);
523 } else {
524 /* AUTOMATIC is meaningless in AP mode */
525 if (WARN_ON_ONCE(smps_mode == IEEE80211_SMPS_AUTOMATIC))
526 return;
527 if (sdata->u.ap.driver_smps_mode == smps_mode)
528 return;
529 sdata->u.ap.driver_smps_mode = smps_mode;
530 ieee80211_queue_work(&sdata->local->hw,
531 &sdata->u.ap.request_smps_work);
532 }
533 }
534 /* this might change ... don't want non-open drivers using it */
535 EXPORT_SYMBOL_GPL(ieee80211_request_smps);