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
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
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
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 */
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
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
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
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 = skb_put_zero(skb, 24);
211 memcpy(mgmt->da, da, ETH_ALEN);
212 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
213 if (sdata->vif.type == NL80211_IFTYPE_AP ||
214 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
215 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
216 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
217 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
218 memcpy(mgmt->bssid, sdata->vif.cfg.ap_addr, ETH_ALEN);
219 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
220 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
221
222 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
223 IEEE80211_STYPE_ACTION);
224
225 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
226 mgmt->u.action.category = WLAN_CATEGORY_BACK;
227 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
228 mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
229
230 capab = u16_encode_bits(amsdu, IEEE80211_ADDBA_PARAM_AMSDU_MASK);
231 capab |= u16_encode_bits(policy, IEEE80211_ADDBA_PARAM_POLICY_MASK);
232 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
233 capab |= u16_encode_bits(buf_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
234
235 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
236 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
237 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
238
239 if (sta->sta.deflink.he_cap.has_he && addbaext)
240 ieee80211_add_addbaext(sdata, skb, addbaext, buf_size);
241
242 ieee80211_tx_skb(sdata, skb);
243 }
244
245 void __ieee80211_start_rx_ba_session(struct sta_info *sta,
246 u8 dialog_token, u16 timeout,
247 u16 start_seq_num, u16 ba_policy, u16 tid,
248 u16 buf_size, bool tx, bool auto_seq,
249 const struct ieee80211_addba_ext_ie *addbaext)
250 {
251 struct ieee80211_local *local = sta->sdata->local;
252 struct tid_ampdu_rx *tid_agg_rx;
253 struct ieee80211_ampdu_params params = {
254 .sta = &sta->sta,
255 .action = IEEE80211_AMPDU_RX_START,
256 .tid = tid,
257 .amsdu = false,
258 .timeout = timeout,
259 .ssn = start_seq_num,
260 };
261 int i, ret = -EOPNOTSUPP;
262 u16 status = WLAN_STATUS_REQUEST_DECLINED;
263 u16 max_buf_size;
264
265 lockdep_assert_wiphy(sta->local->hw.wiphy);
266
267 if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
268 ht_dbg(sta->sdata,
269 "STA %pM requests BA session on unsupported tid %d\n",
270 sta->sta.addr, tid);
271 goto end;
272 }
273
274 if (!sta->sta.deflink.ht_cap.ht_supported &&
275 !sta->sta.deflink.he_cap.has_he) {
276 ht_dbg(sta->sdata,
277 "STA %pM erroneously requests BA session on tid %d w/o HT\n",
278 sta->sta.addr, tid);
279 /* send a response anyway, it's an error case if we get here */
280 goto end;
281 }
282
283 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
284 ht_dbg(sta->sdata,
285 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
286 sta->sta.addr, tid);
287 goto end;
288 }
289
290 if (sta->sta.deflink.eht_cap.has_eht)
291 max_buf_size = IEEE80211_MAX_AMPDU_BUF_EHT;
292 else if (sta->sta.deflink.he_cap.has_he)
293 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HE;
294 else
295 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
296
297 /* sanity check for incoming parameters:
298 * check if configuration can support the BA policy
299 * and if buffer size does not exceeds max value */
300 /* XXX: check own ht delayed BA capability?? */
301 if (((ba_policy != 1) &&
302 (!(sta->sta.deflink.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
303 (buf_size > max_buf_size)) {
304 status = WLAN_STATUS_INVALID_QOS_PARAM;
305 ht_dbg_ratelimited(sta->sdata,
306 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
307 sta->sta.addr, tid, ba_policy, buf_size);
308 goto end;
309 }
310 /* determine default buffer size */
311 if (buf_size == 0)
312 buf_size = max_buf_size;
313
314 /* make sure the size doesn't exceed the maximum supported by the hw */
315 if (buf_size > sta->sta.max_rx_aggregation_subframes)
316 buf_size = sta->sta.max_rx_aggregation_subframes;
317 params.buf_size = buf_size;
318
319 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
320 buf_size, sta->sta.addr);
321
322 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
323 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
324 struct tid_ampdu_rx *tid_rx;
325
326 ht_dbg_ratelimited(sta->sdata,
327 "updated AddBA Req from %pM on tid %u\n",
328 sta->sta.addr, tid);
329 /* We have no API to update the timeout value in the
330 * driver so reject the timeout update if the timeout
331 * changed. If it did not change, i.e., no real update,
332 * just reply with success.
333 */
334 rcu_read_lock();
335 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
336 if (tid_rx && tid_rx->timeout == timeout)
337 status = WLAN_STATUS_SUCCESS;
338 else
339 status = WLAN_STATUS_REQUEST_DECLINED;
340 rcu_read_unlock();
341 goto end;
342 }
343
344 ht_dbg_ratelimited(sta->sdata,
345 "unexpected AddBA Req from %pM on tid %u\n",
346 sta->sta.addr, tid);
347
348 /* delete existing Rx BA session on the same tid */
349 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
350 WLAN_STATUS_UNSPECIFIED_QOS,
351 false);
352 }
353
354 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
355 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
356 ht_dbg(sta->sdata,
357 "Rx A-MPDU request on %pM tid %d result %d\n",
358 sta->sta.addr, tid, ret);
359 if (!ret)
360 status = WLAN_STATUS_SUCCESS;
361 goto end;
362 }
363
364 /* prepare A-MPDU MLME for Rx aggregation */
365 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
366 if (!tid_agg_rx)
367 goto end;
368
369 spin_lock_init(&tid_agg_rx->reorder_lock);
370
371 /* rx timer */
372 timer_setup(&tid_agg_rx->session_timer,
373 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
374
375 /* rx reorder timer */
376 timer_setup(&tid_agg_rx->reorder_timer,
377 sta_rx_agg_reorder_timer_expired, 0);
378
379 /* prepare reordering buffer */
380 tid_agg_rx->reorder_buf =
381 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
382 tid_agg_rx->reorder_time =
383 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
384 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
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 for (i = 0; i < buf_size; i++)
392 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
393
394 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
395 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
396 sta->sta.addr, tid, ret);
397 if (ret) {
398 kfree(tid_agg_rx->reorder_buf);
399 kfree(tid_agg_rx->reorder_time);
400 kfree(tid_agg_rx);
401 goto end;
402 }
403
404 /* update data */
405 tid_agg_rx->ssn = start_seq_num;
406 tid_agg_rx->head_seq_num = start_seq_num;
407 tid_agg_rx->buf_size = buf_size;
408 tid_agg_rx->timeout = timeout;
409 tid_agg_rx->stored_mpdu_num = 0;
410 tid_agg_rx->auto_seq = auto_seq;
411 tid_agg_rx->started = false;
412 tid_agg_rx->reorder_buf_filtered = 0;
413 tid_agg_rx->tid = tid;
414 tid_agg_rx->sta = sta;
415 status = WLAN_STATUS_SUCCESS;
416
417 /* activate it for RX */
418 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
419
420 if (timeout) {
421 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
422 tid_agg_rx->last_rx = jiffies;
423 }
424
425 end:
426 if (status == WLAN_STATUS_SUCCESS) {
427 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
428 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
429 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
430 }
431
432 if (tx)
433 ieee80211_send_addba_resp(sta, sta->sta.addr, tid,
434 dialog_token, status, 1, buf_size,
435 timeout, addbaext);
436 }
437
438 void ieee80211_process_addba_request(struct ieee80211_local *local,
439 struct sta_info *sta,
440 struct ieee80211_mgmt *mgmt,
441 size_t len)
442 {
443 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
444 struct ieee802_11_elems *elems = NULL;
445 u8 dialog_token;
446 int ies_len;
447
448 /* extract session parameters from addba request frame */
449 dialog_token = mgmt->u.action.u.addba_req.dialog_token;
450 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
451 start_seq_num =
452 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
453
454 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
455 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
456 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
457 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
458
459 ies_len = len - offsetof(struct ieee80211_mgmt,
460 u.action.u.addba_req.variable);
461 if (ies_len) {
462 elems = ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable,
463 ies_len, true, NULL);
464 if (!elems || elems->parse_error)
465 goto free;
466 }
467
468 if (sta->sta.deflink.eht_cap.has_eht && elems && elems->addba_ext_ie) {
469 u8 buf_size_1k = u8_get_bits(elems->addba_ext_ie->data,
470 IEEE80211_ADDBA_EXT_BUF_SIZE_MASK);
471
472 buf_size |= buf_size_1k << IEEE80211_ADDBA_EXT_BUF_SIZE_SHIFT;
473 }
474
475 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
476 start_seq_num, ba_policy, tid,
477 buf_size, true, false,
478 elems ? elems->addba_ext_ie : NULL);
479 free:
480 kfree(elems);
481 }
482
483 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif,
484 const u8 *addr, unsigned int tid)
485 {
486 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
487 struct sta_info *sta;
488
489 rcu_read_lock();
490 sta = sta_info_get_bss(sdata, addr);
491 if (!sta)
492 goto unlock;
493
494 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
495 wiphy_work_queue(sta->local->hw.wiphy, &sta->ampdu_mlme.work);
496 unlock:
497 rcu_read_unlock();
498 }
499 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
500
501 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
502 const u8 *addr, unsigned int tid)
503 {
504 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
505 struct sta_info *sta;
506
507 rcu_read_lock();
508 sta = sta_info_get_bss(sdata, addr);
509 if (!sta)
510 goto unlock;
511
512 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
513 wiphy_work_queue(sta->local->hw.wiphy, &sta->ampdu_mlme.work);
514
515 unlock:
516 rcu_read_unlock();
517 }
518 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);
519
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