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 ieee80211_sub_if_data * sdata,struct sk_buff * skb,const struct ieee80211_addba_ext_ie * req,u16 buf_size)173 static void ieee80211_add_addbaext(struct ieee80211_sub_if_data *sdata,
174 struct sk_buff *skb,
175 const struct ieee80211_addba_ext_ie *req,
176 u16 buf_size)
177 {
178 struct ieee80211_addba_ext_ie *resp;
179 u8 *pos;
180
181 pos = skb_put_zero(skb, 2 + sizeof(struct ieee80211_addba_ext_ie));
182 *pos++ = WLAN_EID_ADDBA_EXT;
183 *pos++ = sizeof(struct ieee80211_addba_ext_ie);
184 resp = (struct ieee80211_addba_ext_ie *)pos;
185 resp->data = req->data & IEEE80211_ADDBA_EXT_NO_FRAG;
186
187 resp->data |= u8_encode_bits(buf_size >> IEEE80211_ADDBA_EXT_BUF_SIZE_SHIFT,
188 IEEE80211_ADDBA_EXT_BUF_SIZE_MASK);
189 }
190
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 struct ieee80211_addba_ext_ie * addbaext)191 static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid,
192 u8 dialog_token, u16 status, u16 policy,
193 u16 buf_size, u16 timeout,
194 const struct ieee80211_addba_ext_ie *addbaext)
195 {
196 struct ieee80211_sub_if_data *sdata = sta->sdata;
197 struct ieee80211_local *local = sdata->local;
198 struct sk_buff *skb;
199 struct ieee80211_mgmt *mgmt;
200 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
201 u16 capab;
202
203 skb = dev_alloc_skb(sizeof(*mgmt) +
204 2 + sizeof(struct ieee80211_addba_ext_ie) +
205 local->hw.extra_tx_headroom);
206 if (!skb)
207 return;
208
209 skb_reserve(skb, local->hw.extra_tx_headroom);
210 mgmt = ieee80211_mgmt_ba(skb, da, sdata);
211
212 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
213 mgmt->u.action.category = WLAN_CATEGORY_BACK;
214 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
215 mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
216
217 capab = u16_encode_bits(amsdu, IEEE80211_ADDBA_PARAM_AMSDU_MASK);
218 capab |= u16_encode_bits(policy, IEEE80211_ADDBA_PARAM_POLICY_MASK);
219 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
220 capab |= u16_encode_bits(buf_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
221
222 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
223 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
224 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
225
226 if (sta->sta.deflink.he_cap.has_he && addbaext)
227 ieee80211_add_addbaext(sdata, skb, addbaext, buf_size);
228
229 ieee80211_tx_skb(sdata, skb);
230 }
231
__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 struct ieee80211_addba_ext_ie * addbaext)232 void __ieee80211_start_rx_ba_session(struct sta_info *sta,
233 u8 dialog_token, u16 timeout,
234 u16 start_seq_num, u16 ba_policy, u16 tid,
235 u16 buf_size, bool tx, bool auto_seq,
236 const struct ieee80211_addba_ext_ie *addbaext)
237 {
238 struct ieee80211_local *local = sta->sdata->local;
239 struct tid_ampdu_rx *tid_agg_rx;
240 struct ieee80211_ampdu_params params = {
241 .sta = &sta->sta,
242 .action = IEEE80211_AMPDU_RX_START,
243 .tid = tid,
244 .amsdu = false,
245 .timeout = timeout,
246 .ssn = start_seq_num,
247 };
248 int i, ret = -EOPNOTSUPP;
249 u16 status = WLAN_STATUS_REQUEST_DECLINED;
250 u16 max_buf_size;
251
252 lockdep_assert_wiphy(sta->local->hw.wiphy);
253
254 if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
255 ht_dbg(sta->sdata,
256 "STA %pM requests BA session on unsupported tid %d\n",
257 sta->sta.addr, tid);
258 goto end;
259 }
260
261 if (!sta->sta.deflink.ht_cap.ht_supported &&
262 !sta->sta.deflink.he_cap.has_he) {
263 ht_dbg(sta->sdata,
264 "STA %pM erroneously requests BA session on tid %d w/o HT\n",
265 sta->sta.addr, tid);
266 /* send a response anyway, it's an error case if we get here */
267 goto end;
268 }
269
270 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
271 ht_dbg(sta->sdata,
272 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
273 sta->sta.addr, tid);
274 goto end;
275 }
276
277 if (sta->sta.deflink.eht_cap.has_eht)
278 max_buf_size = IEEE80211_MAX_AMPDU_BUF_EHT;
279 else if (sta->sta.deflink.he_cap.has_he)
280 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HE;
281 else
282 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
283
284 /* sanity check for incoming parameters:
285 * check if configuration can support the BA policy
286 * and if buffer size does not exceeds max value */
287 /* XXX: check own ht delayed BA capability?? */
288 if (((ba_policy != 1) &&
289 (!(sta->sta.deflink.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
290 (buf_size > max_buf_size)) {
291 status = WLAN_STATUS_INVALID_QOS_PARAM;
292 ht_dbg_ratelimited(sta->sdata,
293 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
294 sta->sta.addr, tid, ba_policy, buf_size);
295 goto end;
296 }
297 /* determine default buffer size */
298 if (buf_size == 0)
299 buf_size = max_buf_size;
300
301 /* make sure the size doesn't exceed the maximum supported by the hw */
302 if (buf_size > sta->sta.max_rx_aggregation_subframes)
303 buf_size = sta->sta.max_rx_aggregation_subframes;
304 params.buf_size = buf_size;
305
306 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
307 buf_size, sta->sta.addr);
308
309 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
310 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
311 struct tid_ampdu_rx *tid_rx;
312
313 ht_dbg_ratelimited(sta->sdata,
314 "updated AddBA Req from %pM on tid %u\n",
315 sta->sta.addr, tid);
316 /* We have no API to update the timeout value in the
317 * driver so reject the timeout update if the timeout
318 * changed. If it did not change, i.e., no real update,
319 * just reply with success.
320 */
321 rcu_read_lock();
322 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
323 if (tid_rx && tid_rx->timeout == timeout)
324 status = WLAN_STATUS_SUCCESS;
325 else
326 status = WLAN_STATUS_REQUEST_DECLINED;
327 rcu_read_unlock();
328 goto end;
329 }
330
331 ht_dbg_ratelimited(sta->sdata,
332 "unexpected AddBA Req from %pM on tid %u\n",
333 sta->sta.addr, tid);
334
335 /* delete existing Rx BA session on the same tid */
336 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
337 WLAN_STATUS_UNSPECIFIED_QOS,
338 false);
339 }
340
341 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
342 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
343 ht_dbg(sta->sdata,
344 "Rx A-MPDU request on %pM tid %d result %d\n",
345 sta->sta.addr, tid, ret);
346 if (!ret)
347 status = WLAN_STATUS_SUCCESS;
348 goto end;
349 }
350
351 /* prepare A-MPDU MLME for Rx aggregation */
352 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
353 if (!tid_agg_rx)
354 goto end;
355
356 spin_lock_init(&tid_agg_rx->reorder_lock);
357
358 /* rx timer */
359 timer_setup(&tid_agg_rx->session_timer,
360 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
361
362 /* rx reorder timer */
363 timer_setup(&tid_agg_rx->reorder_timer,
364 sta_rx_agg_reorder_timer_expired, 0);
365
366 /* prepare reordering buffer */
367 tid_agg_rx->reorder_buf =
368 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
369 tid_agg_rx->reorder_time =
370 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
371 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
372 kfree(tid_agg_rx->reorder_buf);
373 kfree(tid_agg_rx->reorder_time);
374 kfree(tid_agg_rx);
375 goto end;
376 }
377
378 for (i = 0; i < buf_size; i++)
379 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
380
381 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
382 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
383 sta->sta.addr, tid, ret);
384 if (ret) {
385 kfree(tid_agg_rx->reorder_buf);
386 kfree(tid_agg_rx->reorder_time);
387 kfree(tid_agg_rx);
388 goto end;
389 }
390
391 /* update data */
392 tid_agg_rx->ssn = start_seq_num;
393 tid_agg_rx->head_seq_num = start_seq_num;
394 tid_agg_rx->buf_size = buf_size;
395 tid_agg_rx->timeout = timeout;
396 tid_agg_rx->stored_mpdu_num = 0;
397 tid_agg_rx->auto_seq = auto_seq;
398 tid_agg_rx->started = false;
399 tid_agg_rx->reorder_buf_filtered = 0;
400 tid_agg_rx->tid = tid;
401 tid_agg_rx->sta = sta;
402 status = WLAN_STATUS_SUCCESS;
403
404 /* activate it for RX */
405 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
406
407 if (timeout) {
408 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
409 tid_agg_rx->last_rx = jiffies;
410 }
411
412 end:
413 if (status == WLAN_STATUS_SUCCESS) {
414 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
415 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
416 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
417 }
418
419 if (tx)
420 ieee80211_send_addba_resp(sta, sta->sta.addr, tid,
421 dialog_token, status, 1, buf_size,
422 timeout, addbaext);
423 }
424
ieee80211_process_addba_request(struct ieee80211_local * local,struct sta_info * sta,struct ieee80211_mgmt * mgmt,size_t len)425 void ieee80211_process_addba_request(struct ieee80211_local *local,
426 struct sta_info *sta,
427 struct ieee80211_mgmt *mgmt,
428 size_t len)
429 {
430 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
431 struct ieee802_11_elems *elems = NULL;
432 u8 dialog_token;
433 int ies_len;
434
435 /* extract session parameters from addba request frame */
436 dialog_token = mgmt->u.action.u.addba_req.dialog_token;
437 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
438 start_seq_num =
439 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
440
441 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
442 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
443 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
444 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
445
446 ies_len = len - offsetof(struct ieee80211_mgmt,
447 u.action.u.addba_req.variable);
448 if (ies_len) {
449 elems = ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable,
450 ies_len, true, NULL);
451 if (!elems || elems->parse_error)
452 goto free;
453 }
454
455 if (sta->sta.deflink.eht_cap.has_eht && elems && elems->addba_ext_ie) {
456 u8 buf_size_1k = u8_get_bits(elems->addba_ext_ie->data,
457 IEEE80211_ADDBA_EXT_BUF_SIZE_MASK);
458
459 buf_size |= buf_size_1k << IEEE80211_ADDBA_EXT_BUF_SIZE_SHIFT;
460 }
461
462 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
463 start_seq_num, ba_policy, tid,
464 buf_size, true, false,
465 elems ? elems->addba_ext_ie : NULL);
466 free:
467 kfree(elems);
468 }
469
ieee80211_manage_rx_ba_offl(struct ieee80211_vif * vif,const u8 * addr,unsigned int tid)470 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif,
471 const u8 *addr, unsigned int tid)
472 {
473 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
474 struct sta_info *sta;
475
476 rcu_read_lock();
477 sta = sta_info_get_bss(sdata, addr);
478 if (!sta)
479 goto unlock;
480
481 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
482 wiphy_work_queue(sta->local->hw.wiphy, &sta->ampdu_mlme.work);
483 unlock:
484 rcu_read_unlock();
485 }
486 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
487
ieee80211_rx_ba_timer_expired(struct ieee80211_vif * vif,const u8 * addr,unsigned int tid)488 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
489 const u8 *addr, unsigned int tid)
490 {
491 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
492 struct sta_info *sta;
493
494 rcu_read_lock();
495 sta = sta_info_get_bss(sdata, addr);
496 if (!sta)
497 goto unlock;
498
499 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
500 wiphy_work_queue(sta->local->hw.wiphy, &sta->ampdu_mlme.work);
501
502 unlock:
503 rcu_read_unlock();
504 }
505 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);
506