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v5.14.15
  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) 2018-2020 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
 45static 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
 58void ___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_held(&sta->ampdu_mlme.mtx);
 73
 74	tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
 75					lockdep_is_held(&sta->ampdu_mlme.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, &params))
 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
117void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
118				    u16 initiator, u16 reason, bool tx)
119{
120	mutex_lock(&sta->ampdu_mlme.mtx);
121	___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
122	mutex_unlock(&sta->ampdu_mlme.mtx);
123}
124
125void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
126				  const u8 *addr)
127{
128	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
129	struct sta_info *sta;
130	int i;
131
132	rcu_read_lock();
133	sta = sta_info_get_bss(sdata, addr);
134	if (!sta) {
135		rcu_read_unlock();
136		return;
137	}
138
139	for (i = 0; i < IEEE80211_NUM_TIDS; i++)
140		if (ba_rx_bitmap & BIT(i))
141			set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
142
143	ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
144	rcu_read_unlock();
145}
146EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
147
148/*
149 * After accepting the AddBA Request we activated a timer,
150 * resetting it after each frame that arrives from the originator.
151 */
152static void sta_rx_agg_session_timer_expired(struct timer_list *t)
153{
154	struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, session_timer);
155	struct sta_info *sta = tid_rx->sta;
156	u8 tid = tid_rx->tid;
157	unsigned long timeout;
158
159	timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
160	if (time_is_after_jiffies(timeout)) {
161		mod_timer(&tid_rx->session_timer, timeout);
162		return;
163	}
164
165	ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
166	       sta->sta.addr, tid);
167
168	set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
169	ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
170}
171
172static void sta_rx_agg_reorder_timer_expired(struct timer_list *t)
173{
174	struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer);
175
176	rcu_read_lock();
177	ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid);
178	rcu_read_unlock();
179}
180
181static void ieee80211_add_addbaext(struct ieee80211_sub_if_data *sdata,
182				   struct sk_buff *skb,
183				   const struct ieee80211_addba_ext_ie *req)
 
184{
185	struct ieee80211_supported_band *sband;
186	struct ieee80211_addba_ext_ie *resp;
187	const struct ieee80211_sta_he_cap *he_cap;
188	u8 frag_level, cap_frag_level;
189	u8 *pos;
190
191	sband = ieee80211_get_sband(sdata);
192	if (!sband)
193		return;
194	he_cap = ieee80211_get_he_iftype_cap(sband, sdata->vif.type);
195	if (!he_cap)
196		return;
197
198	pos = skb_put_zero(skb, 2 + sizeof(struct ieee80211_addba_ext_ie));
199	*pos++ = WLAN_EID_ADDBA_EXT;
200	*pos++ = sizeof(struct ieee80211_addba_ext_ie);
201	resp = (struct ieee80211_addba_ext_ie *)pos;
202	resp->data = req->data & IEEE80211_ADDBA_EXT_NO_FRAG;
203
204	frag_level = u32_get_bits(req->data,
205				  IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK);
206	cap_frag_level = u32_get_bits(he_cap->he_cap_elem.mac_cap_info[0],
207				      IEEE80211_HE_MAC_CAP0_DYNAMIC_FRAG_MASK);
208	if (frag_level > cap_frag_level)
209		frag_level = cap_frag_level;
210	resp->data |= u8_encode_bits(frag_level,
211				     IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK);
212}
213
214static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid,
215				      u8 dialog_token, u16 status, u16 policy,
216				      u16 buf_size, u16 timeout,
217				      const struct ieee80211_addba_ext_ie *addbaext)
218{
219	struct ieee80211_sub_if_data *sdata = sta->sdata;
220	struct ieee80211_local *local = sdata->local;
221	struct sk_buff *skb;
222	struct ieee80211_mgmt *mgmt;
223	bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
224	u16 capab;
225
226	skb = dev_alloc_skb(sizeof(*mgmt) +
227		    2 + sizeof(struct ieee80211_addba_ext_ie) +
228		    local->hw.extra_tx_headroom);
229	if (!skb)
230		return;
231
232	skb_reserve(skb, local->hw.extra_tx_headroom);
233	mgmt = skb_put_zero(skb, 24);
234	memcpy(mgmt->da, da, ETH_ALEN);
235	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
236	if (sdata->vif.type == NL80211_IFTYPE_AP ||
237	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
238	    sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
239		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
240	else if (sdata->vif.type == NL80211_IFTYPE_STATION)
241		memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
242	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
243		memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
244
245	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
246					  IEEE80211_STYPE_ACTION);
247
248	skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
249	mgmt->u.action.category = WLAN_CATEGORY_BACK;
250	mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
251	mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
252
253	capab = u16_encode_bits(amsdu, IEEE80211_ADDBA_PARAM_AMSDU_MASK);
254	capab |= u16_encode_bits(policy, IEEE80211_ADDBA_PARAM_POLICY_MASK);
255	capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
256	capab |= u16_encode_bits(buf_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
257
258	mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
259	mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
260	mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
261
262	if (sta->sta.he_cap.has_he && addbaext)
263		ieee80211_add_addbaext(sdata, skb, addbaext);
264
265	ieee80211_tx_skb(sdata, skb);
266}
267
268void ___ieee80211_start_rx_ba_session(struct sta_info *sta,
269				      u8 dialog_token, u16 timeout,
270				      u16 start_seq_num, u16 ba_policy, u16 tid,
271				      u16 buf_size, bool tx, bool auto_seq,
272				      const struct ieee80211_addba_ext_ie *addbaext)
273{
274	struct ieee80211_local *local = sta->sdata->local;
275	struct tid_ampdu_rx *tid_agg_rx;
276	struct ieee80211_ampdu_params params = {
277		.sta = &sta->sta,
278		.action = IEEE80211_AMPDU_RX_START,
279		.tid = tid,
280		.amsdu = false,
281		.timeout = timeout,
282		.ssn = start_seq_num,
283	};
284	int i, ret = -EOPNOTSUPP;
285	u16 status = WLAN_STATUS_REQUEST_DECLINED;
286	u16 max_buf_size;
287
 
 
288	if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
289		ht_dbg(sta->sdata,
290		       "STA %pM requests BA session on unsupported tid %d\n",
291		       sta->sta.addr, tid);
292		goto end;
293	}
294
295	if (!sta->sta.ht_cap.ht_supported &&
296	    sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ) {
297		ht_dbg(sta->sdata,
298		       "STA %pM erroneously requests BA session on tid %d w/o QoS\n",
299		       sta->sta.addr, tid);
300		/* send a response anyway, it's an error case if we get here */
301		goto end;
302	}
303
304	if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
305		ht_dbg(sta->sdata,
306		       "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
307		       sta->sta.addr, tid);
308		goto end;
309	}
310
311	if (sta->sta.he_cap.has_he)
312		max_buf_size = IEEE80211_MAX_AMPDU_BUF;
 
 
313	else
314		max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
315
316	/* sanity check for incoming parameters:
317	 * check if configuration can support the BA policy
318	 * and if buffer size does not exceeds max value */
319	/* XXX: check own ht delayed BA capability?? */
320	if (((ba_policy != 1) &&
321	     (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
322	    (buf_size > max_buf_size)) {
323		status = WLAN_STATUS_INVALID_QOS_PARAM;
324		ht_dbg_ratelimited(sta->sdata,
325				   "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
326				   sta->sta.addr, tid, ba_policy, buf_size);
327		goto end;
328	}
329	/* determine default buffer size */
330	if (buf_size == 0)
331		buf_size = max_buf_size;
332
333	/* make sure the size doesn't exceed the maximum supported by the hw */
334	if (buf_size > sta->sta.max_rx_aggregation_subframes)
335		buf_size = sta->sta.max_rx_aggregation_subframes;
336	params.buf_size = buf_size;
337
338	ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
339	       buf_size, sta->sta.addr);
340
341	/* examine state machine */
342	lockdep_assert_held(&sta->ampdu_mlme.mtx);
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, &params);
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, &params);
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
447end:
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, addbaext);
458}
459
460static void __ieee80211_start_rx_ba_session(struct sta_info *sta,
461					    u8 dialog_token, u16 timeout,
462					    u16 start_seq_num, u16 ba_policy,
463					    u16 tid, u16 buf_size, bool tx,
464					    bool auto_seq,
465					    const struct ieee80211_addba_ext_ie *addbaext)
466{
467	mutex_lock(&sta->ampdu_mlme.mtx);
468	___ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
469					 start_seq_num, ba_policy, tid,
470					 buf_size, tx, auto_seq, addbaext);
471	mutex_unlock(&sta->ampdu_mlme.mtx);
472}
473
474void ieee80211_process_addba_request(struct ieee80211_local *local,
475				     struct sta_info *sta,
476				     struct ieee80211_mgmt *mgmt,
477				     size_t len)
478{
479	u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
480	struct ieee802_11_elems elems = { };
481	u8 dialog_token;
482	int ies_len;
483
484	/* extract session parameters from addba request frame */
485	dialog_token = mgmt->u.action.u.addba_req.dialog_token;
486	timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
487	start_seq_num =
488		le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
489
490	capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
491	ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
492	tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
493	buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
494
495	ies_len = len - offsetof(struct ieee80211_mgmt,
496				 u.action.u.addba_req.variable);
497	if (ies_len) {
498		ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable,
499                                ies_len, true, &elems, mgmt->bssid, NULL);
500		if (elems.parse_error)
501			return;
 
 
 
 
 
 
 
502	}
503
504	__ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
505					start_seq_num, ba_policy, tid,
506					buf_size, true, false,
507					elems.addba_ext_ie);
 
 
508}
509
510void ieee80211_manage_rx_ba_offl(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 ieee80211_local *local = sdata->local;
515	struct sta_info *sta;
516
517	rcu_read_lock();
518	sta = sta_info_get_bss(sdata, addr);
519	if (!sta)
520		goto unlock;
521
522	set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
523	ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
524 unlock:
525	rcu_read_unlock();
526}
527EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
528
529void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
530				   const u8 *addr, unsigned int tid)
531{
532	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
533	struct ieee80211_local *local = sdata->local;
534	struct sta_info *sta;
535
536	rcu_read_lock();
537	sta = sta_info_get_bss(sdata, addr);
538	if (!sta)
539		goto unlock;
540
541	set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
542	ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
543
544 unlock:
545	rcu_read_unlock();
546}
547EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);
v6.9.4
  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
 45static 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
 58void __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, &params))
 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
 
 
 
 
 
 
 
 
117void 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}
138EXPORT_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 */
144static 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
164static 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
173static 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
191static 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
245void __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, &params);
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, &params);
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
425end:
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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
438void 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);
479free:
480	kfree(elems);
481}
482
483void 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}
499EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
500
501void 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}
518EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);