1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * HT handling
4 *
5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6 * Copyright 2002-2005, Instant802 Networks, Inc.
7 * Copyright 2005-2006, Devicescape Software, Inc.
8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10 * Copyright 2007-2010, Intel Corporation
11 * Copyright(c) 2015-2017 Intel Deutschland GmbH
12 * Copyright (C) 2018-2023 Intel Corporation
13 */
14
15 /**
16 * DOC: RX A-MPDU aggregation
17 *
18 * Aggregation on the RX side requires only implementing the
19 * @ampdu_action callback that is invoked to start/stop any
20 * block-ack sessions for RX aggregation.
21 *
22 * When RX aggregation is started by the peer, the driver is
23 * notified via @ampdu_action function, with the
24 * %IEEE80211_AMPDU_RX_START action, and may reject the request
25 * in which case a negative response is sent to the peer, if it
26 * accepts it a positive response is sent.
27 *
28 * While the session is active, the device/driver are required
29 * to de-aggregate frames and pass them up one by one to mac80211,
30 * which will handle the reorder buffer.
31 *
32 * When the aggregation session is stopped again by the peer or
33 * ourselves, the driver's @ampdu_action function will be called
34 * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the
35 * call must not fail.
36 */
37
38 #include <linux/ieee80211.h>
39 #include <linux/slab.h>
40 #include <linux/export.h>
41 #include <net/mac80211.h>
42 #include "ieee80211_i.h"
43 #include "driver-ops.h"
44
ieee80211_free_tid_rx(struct rcu_head * h)45 static void ieee80211_free_tid_rx(struct rcu_head *h)
46 {
47 struct tid_ampdu_rx *tid_rx =
48 container_of(h, struct tid_ampdu_rx, rcu_head);
49 int i;
50
51 for (i = 0; i < tid_rx->buf_size; i++)
52 __skb_queue_purge(&tid_rx->reorder_buf[i]);
53 kfree(tid_rx->reorder_buf);
54 kfree(tid_rx->reorder_time);
55 kfree(tid_rx);
56 }
57
__ieee80211_stop_rx_ba_session(struct sta_info * sta,u16 tid,u16 initiator,u16 reason,bool tx)58 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
59 u16 initiator, u16 reason, bool tx)
60 {
61 struct ieee80211_local *local = sta->local;
62 struct tid_ampdu_rx *tid_rx;
63 struct ieee80211_ampdu_params params = {
64 .sta = &sta->sta,
65 .action = IEEE80211_AMPDU_RX_STOP,
66 .tid = tid,
67 .amsdu = false,
68 .timeout = 0,
69 .ssn = 0,
70 };
71
72 lockdep_assert_wiphy(sta->local->hw.wiphy);
73
74 tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
75 lockdep_is_held(&sta->local->hw.wiphy->mtx));
76
77 if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid))
78 return;
79
80 RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
81 __clear_bit(tid, sta->ampdu_mlme.agg_session_valid);
82
83 ht_dbg(sta->sdata,
84 "Rx BA session stop requested for %pM tid %u %s reason: %d\n",
85 sta->sta.addr, tid,
86 initiator == WLAN_BACK_RECIPIENT ? "recipient" : "initiator",
87 (int)reason);
88
89 if (drv_ampdu_action(local, sta->sdata, ¶ms))
90 sdata_info(sta->sdata,
91 "HW problem - can not stop rx aggregation for %pM tid %d\n",
92 sta->sta.addr, tid);
93
94 /* check if this is a self generated aggregation halt */
95 if (initiator == WLAN_BACK_RECIPIENT && tx)
96 ieee80211_send_delba(sta->sdata, sta->sta.addr,
97 tid, WLAN_BACK_RECIPIENT, reason);
98
99 /*
100 * return here in case tid_rx is not assigned - which will happen if
101 * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set.
102 */
103 if (!tid_rx)
104 return;
105
106 del_timer_sync(&tid_rx->session_timer);
107
108 /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */
109 spin_lock_bh(&tid_rx->reorder_lock);
110 tid_rx->removed = true;
111 spin_unlock_bh(&tid_rx->reorder_lock);
112 del_timer_sync(&tid_rx->reorder_timer);
113
114 call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
115 }
116
ieee80211_stop_rx_ba_session(struct ieee80211_vif * vif,u16 ba_rx_bitmap,const u8 * addr)117 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
118 const u8 *addr)
119 {
120 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
121 struct sta_info *sta;
122 int i;
123
124 rcu_read_lock();
125 sta = sta_info_get_bss(sdata, addr);
126 if (!sta) {
127 rcu_read_unlock();
128 return;
129 }
130
131 for (i = 0; i < IEEE80211_NUM_TIDS; i++)
132 if (ba_rx_bitmap & BIT(i))
133 set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
134
135 wiphy_work_queue(sta->local->hw.wiphy, &sta->ampdu_mlme.work);
136 rcu_read_unlock();
137 }
138 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
139
140 /*
141 * After accepting the AddBA Request we activated a timer,
142 * resetting it after each frame that arrives from the originator.
143 */
sta_rx_agg_session_timer_expired(struct timer_list * t)144 static void sta_rx_agg_session_timer_expired(struct timer_list *t)
145 {
146 struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, session_timer);
147 struct sta_info *sta = tid_rx->sta;
148 u8 tid = tid_rx->tid;
149 unsigned long timeout;
150
151 timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
152 if (time_is_after_jiffies(timeout)) {
153 mod_timer(&tid_rx->session_timer, timeout);
154 return;
155 }
156
157 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
158 sta->sta.addr, tid);
159
160 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
161 wiphy_work_queue(sta->local->hw.wiphy, &sta->ampdu_mlme.work);
162 }
163
sta_rx_agg_reorder_timer_expired(struct timer_list * t)164 static void sta_rx_agg_reorder_timer_expired(struct timer_list *t)
165 {
166 struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer);
167
168 rcu_read_lock();
169 ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid);
170 rcu_read_unlock();
171 }
172
ieee80211_add_addbaext(struct sk_buff * skb,const u8 req_addba_ext_data,u16 buf_size)173 void ieee80211_add_addbaext(struct sk_buff *skb,
174 const u8 req_addba_ext_data,
175 u16 buf_size)
176 {
177 struct ieee80211_addba_ext_ie *addba_ext;
178 u8 *pos;
179
180 pos = skb_put_zero(skb, 2 + sizeof(struct ieee80211_addba_ext_ie));
181 *pos++ = WLAN_EID_ADDBA_EXT;
182 *pos++ = sizeof(struct ieee80211_addba_ext_ie);
183 addba_ext = (struct ieee80211_addba_ext_ie *)pos;
184
185 addba_ext->data = IEEE80211_ADDBA_EXT_NO_FRAG;
186 if (req_addba_ext_data)
187 addba_ext->data &= req_addba_ext_data;
188
189 addba_ext->data |=
190 u8_encode_bits(buf_size >> IEEE80211_ADDBA_EXT_BUF_SIZE_SHIFT,
191 IEEE80211_ADDBA_EXT_BUF_SIZE_MASK);
192 }
193
ieee80211_retrieve_addba_ext_data(struct sta_info * sta,const void * elem_data,ssize_t elem_len,u16 * buf_size)194 u8 ieee80211_retrieve_addba_ext_data(struct sta_info *sta,
195 const void *elem_data, ssize_t elem_len,
196 u16 *buf_size)
197 {
198 struct ieee802_11_elems *elems;
199 u8 buf_size_1k, data = 0;
200
201 if (!sta->sta.deflink.he_cap.has_he)
202 return 0;
203
204 if (elem_len <= 0)
205 return 0;
206
207 elems = ieee802_11_parse_elems(elem_data, elem_len, true, NULL);
208
209 if (elems && !elems->parse_error && elems->addba_ext_ie) {
210 data = elems->addba_ext_ie->data;
211
212 if (!sta->sta.deflink.eht_cap.has_eht || !buf_size)
213 goto free;
214
215 buf_size_1k = u8_get_bits(elems->addba_ext_ie->data,
216 IEEE80211_ADDBA_EXT_BUF_SIZE_MASK);
217 *buf_size |= (u16)buf_size_1k <<
218 IEEE80211_ADDBA_EXT_BUF_SIZE_SHIFT;
219 }
220 free:
221 kfree(elems);
222
223 return data;
224 }
225
ieee80211_send_addba_resp(struct sta_info * sta,u8 * da,u16 tid,u8 dialog_token,u16 status,u16 policy,u16 buf_size,u16 timeout,const u8 req_addba_ext_data)226 static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid,
227 u8 dialog_token, u16 status, u16 policy,
228 u16 buf_size, u16 timeout,
229 const u8 req_addba_ext_data)
230 {
231 struct ieee80211_sub_if_data *sdata = sta->sdata;
232 struct ieee80211_local *local = sdata->local;
233 struct sk_buff *skb;
234 struct ieee80211_mgmt *mgmt;
235 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
236 u16 capab;
237
238 skb = dev_alloc_skb(sizeof(*mgmt) +
239 2 + sizeof(struct ieee80211_addba_ext_ie) +
240 local->hw.extra_tx_headroom);
241 if (!skb)
242 return;
243
244 skb_reserve(skb, local->hw.extra_tx_headroom);
245 mgmt = ieee80211_mgmt_ba(skb, da, sdata);
246
247 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
248 mgmt->u.action.category = WLAN_CATEGORY_BACK;
249 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
250 mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
251
252 capab = u16_encode_bits(amsdu, IEEE80211_ADDBA_PARAM_AMSDU_MASK);
253 capab |= u16_encode_bits(policy, IEEE80211_ADDBA_PARAM_POLICY_MASK);
254 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
255 capab |= u16_encode_bits(buf_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
256
257 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
258 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
259 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
260
261 if (sta->sta.deflink.he_cap.has_he)
262 ieee80211_add_addbaext(skb, req_addba_ext_data, buf_size);
263
264 ieee80211_tx_skb(sdata, skb);
265 }
266
__ieee80211_start_rx_ba_session(struct sta_info * sta,u8 dialog_token,u16 timeout,u16 start_seq_num,u16 ba_policy,u16 tid,u16 buf_size,bool tx,bool auto_seq,const u8 addba_ext_data)267 void __ieee80211_start_rx_ba_session(struct sta_info *sta,
268 u8 dialog_token, u16 timeout,
269 u16 start_seq_num, u16 ba_policy, u16 tid,
270 u16 buf_size, bool tx, bool auto_seq,
271 const u8 addba_ext_data)
272 {
273 struct ieee80211_local *local = sta->sdata->local;
274 struct tid_ampdu_rx *tid_agg_rx;
275 struct ieee80211_ampdu_params params = {
276 .sta = &sta->sta,
277 .action = IEEE80211_AMPDU_RX_START,
278 .tid = tid,
279 .amsdu = false,
280 .timeout = timeout,
281 .ssn = start_seq_num,
282 };
283 int i, ret = -EOPNOTSUPP;
284 u16 status = WLAN_STATUS_REQUEST_DECLINED;
285 u16 max_buf_size;
286
287 lockdep_assert_wiphy(sta->local->hw.wiphy);
288
289 if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
290 ht_dbg(sta->sdata,
291 "STA %pM requests BA session on unsupported tid %d\n",
292 sta->sta.addr, tid);
293 goto end;
294 }
295
296 if (!sta->sta.deflink.ht_cap.ht_supported &&
297 !sta->sta.deflink.he_cap.has_he) {
298 ht_dbg(sta->sdata,
299 "STA %pM erroneously requests BA session on tid %d w/o HT\n",
300 sta->sta.addr, tid);
301 /* send a response anyway, it's an error case if we get here */
302 goto end;
303 }
304
305 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
306 ht_dbg(sta->sdata,
307 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
308 sta->sta.addr, tid);
309 goto end;
310 }
311
312 if (sta->sta.deflink.eht_cap.has_eht)
313 max_buf_size = IEEE80211_MAX_AMPDU_BUF_EHT;
314 else if (sta->sta.deflink.he_cap.has_he)
315 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HE;
316 else
317 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
318
319 /* sanity check for incoming parameters:
320 * check if configuration can support the BA policy
321 * and if buffer size does not exceeds max value */
322 /* XXX: check own ht delayed BA capability?? */
323 if (((ba_policy != 1) &&
324 (!(sta->sta.deflink.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
325 (buf_size > max_buf_size)) {
326 status = WLAN_STATUS_INVALID_QOS_PARAM;
327 ht_dbg_ratelimited(sta->sdata,
328 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
329 sta->sta.addr, tid, ba_policy, buf_size);
330 goto end;
331 }
332 /* determine default buffer size */
333 if (buf_size == 0)
334 buf_size = max_buf_size;
335
336 /* make sure the size doesn't exceed the maximum supported by the hw */
337 if (buf_size > sta->sta.max_rx_aggregation_subframes)
338 buf_size = sta->sta.max_rx_aggregation_subframes;
339 params.buf_size = buf_size;
340
341 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
342 buf_size, sta->sta.addr);
343
344 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
345 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
346 struct tid_ampdu_rx *tid_rx;
347
348 ht_dbg_ratelimited(sta->sdata,
349 "updated AddBA Req from %pM on tid %u\n",
350 sta->sta.addr, tid);
351 /* We have no API to update the timeout value in the
352 * driver so reject the timeout update if the timeout
353 * changed. If it did not change, i.e., no real update,
354 * just reply with success.
355 */
356 rcu_read_lock();
357 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
358 if (tid_rx && tid_rx->timeout == timeout)
359 status = WLAN_STATUS_SUCCESS;
360 else
361 status = WLAN_STATUS_REQUEST_DECLINED;
362 rcu_read_unlock();
363 goto end;
364 }
365
366 ht_dbg_ratelimited(sta->sdata,
367 "unexpected AddBA Req from %pM on tid %u\n",
368 sta->sta.addr, tid);
369
370 /* delete existing Rx BA session on the same tid */
371 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
372 WLAN_STATUS_UNSPECIFIED_QOS,
373 false);
374 }
375
376 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
377 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
378 ht_dbg(sta->sdata,
379 "Rx A-MPDU request on %pM tid %d result %d\n",
380 sta->sta.addr, tid, ret);
381 if (!ret)
382 status = WLAN_STATUS_SUCCESS;
383 goto end;
384 }
385
386 /* prepare A-MPDU MLME for Rx aggregation */
387 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
388 if (!tid_agg_rx)
389 goto end;
390
391 spin_lock_init(&tid_agg_rx->reorder_lock);
392
393 /* rx timer */
394 timer_setup(&tid_agg_rx->session_timer,
395 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
396
397 /* rx reorder timer */
398 timer_setup(&tid_agg_rx->reorder_timer,
399 sta_rx_agg_reorder_timer_expired, 0);
400
401 /* prepare reordering buffer */
402 tid_agg_rx->reorder_buf =
403 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
404 tid_agg_rx->reorder_time =
405 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
406 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
407 kfree(tid_agg_rx->reorder_buf);
408 kfree(tid_agg_rx->reorder_time);
409 kfree(tid_agg_rx);
410 goto end;
411 }
412
413 for (i = 0; i < buf_size; i++)
414 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
415
416 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
417 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
418 sta->sta.addr, tid, ret);
419 if (ret) {
420 kfree(tid_agg_rx->reorder_buf);
421 kfree(tid_agg_rx->reorder_time);
422 kfree(tid_agg_rx);
423 goto end;
424 }
425
426 /* update data */
427 tid_agg_rx->ssn = start_seq_num;
428 tid_agg_rx->head_seq_num = start_seq_num;
429 tid_agg_rx->buf_size = buf_size;
430 tid_agg_rx->timeout = timeout;
431 tid_agg_rx->stored_mpdu_num = 0;
432 tid_agg_rx->auto_seq = auto_seq;
433 tid_agg_rx->started = false;
434 tid_agg_rx->reorder_buf_filtered = 0;
435 tid_agg_rx->tid = tid;
436 tid_agg_rx->sta = sta;
437 status = WLAN_STATUS_SUCCESS;
438
439 /* activate it for RX */
440 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
441
442 if (timeout) {
443 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
444 tid_agg_rx->last_rx = jiffies;
445 }
446
447 end:
448 if (status == WLAN_STATUS_SUCCESS) {
449 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
450 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
451 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
452 }
453
454 if (tx)
455 ieee80211_send_addba_resp(sta, sta->sta.addr, tid,
456 dialog_token, status, 1, buf_size,
457 timeout, addba_ext_data);
458 }
459
ieee80211_process_addba_request(struct ieee80211_local * local,struct sta_info * sta,struct ieee80211_mgmt * mgmt,size_t len)460 void ieee80211_process_addba_request(struct ieee80211_local *local,
461 struct sta_info *sta,
462 struct ieee80211_mgmt *mgmt,
463 size_t len)
464 {
465 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
466 u8 dialog_token, addba_ext_data;
467
468 /* extract session parameters from addba request frame */
469 dialog_token = mgmt->u.action.u.addba_req.dialog_token;
470 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
471 start_seq_num =
472 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
473
474 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
475 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
476 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
477 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
478
479 addba_ext_data =
480 ieee80211_retrieve_addba_ext_data(sta,
481 mgmt->u.action.u.addba_req.variable,
482 len -
483 offsetof(typeof(*mgmt),
484 u.action.u.addba_req.variable),
485 &buf_size);
486
487 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
488 start_seq_num, ba_policy, tid,
489 buf_size, true, false, addba_ext_data);
490 }
491
ieee80211_manage_rx_ba_offl(struct ieee80211_vif * vif,const u8 * addr,unsigned int tid)492 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif,
493 const u8 *addr, unsigned int tid)
494 {
495 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
496 struct sta_info *sta;
497
498 rcu_read_lock();
499 sta = sta_info_get_bss(sdata, addr);
500 if (!sta)
501 goto unlock;
502
503 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
504 wiphy_work_queue(sta->local->hw.wiphy, &sta->ampdu_mlme.work);
505 unlock:
506 rcu_read_unlock();
507 }
508 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
509
ieee80211_rx_ba_timer_expired(struct ieee80211_vif * vif,const u8 * addr,unsigned int tid)510 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
511 const u8 *addr, unsigned int tid)
512 {
513 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
514 struct sta_info *sta;
515
516 rcu_read_lock();
517 sta = sta_info_get_bss(sdata, addr);
518 if (!sta)
519 goto unlock;
520
521 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
522 wiphy_work_queue(sta->local->hw.wiphy, &sta->ampdu_mlme.work);
523
524 unlock:
525 rcu_read_unlock();
526 }
527 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);
528