spectmgmt.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * spectrum management
  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 2007-2008, Intel Corporation
 11 * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
 12 * Copyright (C) 2018, 2020, 2022-2024 Intel Corporation
 13 */
 14
 15#include <linux/ieee80211.h>
 16#include <net/cfg80211.h>
 17#include <net/mac80211.h>
 18#include "ieee80211_i.h"
 19#include "sta_info.h"
 20#include "wme.h"
 21
 22static bool
 23wbcs_elem_to_chandef(const struct ieee80211_wide_bw_chansw_ie *wbcs_elem,
 24		     struct cfg80211_chan_def *chandef)
 25{
 26	u8 ccfs0 = wbcs_elem->new_center_freq_seg0;
 27	u8 ccfs1 = wbcs_elem->new_center_freq_seg1;
 28	u32 cf0 = ieee80211_channel_to_frequency(ccfs0, chandef->chan->band);
 29	u32 cf1 = ieee80211_channel_to_frequency(ccfs1, chandef->chan->band);
 30
 31	switch (wbcs_elem->new_channel_width) {
 32	case IEEE80211_VHT_CHANWIDTH_160MHZ:
 33		/* deprecated encoding */
 34		chandef->width = NL80211_CHAN_WIDTH_160;
 35		chandef->center_freq1 = cf0;
 36		break;
 37	case IEEE80211_VHT_CHANWIDTH_80P80MHZ:
 38		/* deprecated encoding */
 39		chandef->width = NL80211_CHAN_WIDTH_80P80;
 40		chandef->center_freq1 = cf0;
 41		chandef->center_freq2 = cf1;
 42		break;
 43	case IEEE80211_VHT_CHANWIDTH_80MHZ:
 44		chandef->width = NL80211_CHAN_WIDTH_80;
 45		chandef->center_freq1 = cf0;
 46
 47		if (ccfs1) {
 48			u8 diff = abs(ccfs0 - ccfs1);
 49
 50			if (diff == 8) {
 51				chandef->width = NL80211_CHAN_WIDTH_160;
 52				chandef->center_freq1 = cf1;
 53			} else if (diff > 8) {
 54				chandef->width = NL80211_CHAN_WIDTH_80P80;
 55				chandef->center_freq2 = cf1;
 56			}
 57		}
 58		break;
 59	case IEEE80211_VHT_CHANWIDTH_USE_HT:
 60	default:
 61		/* If the WBCS Element is present, new channel bandwidth is
 62		 * at least 40 MHz.
 63		 */
 64		chandef->width = NL80211_CHAN_WIDTH_40;
 65		chandef->center_freq1 = cf0;
 66		break;
 67	}
 68
 69	return cfg80211_chandef_valid(chandef);
 70}
 71
 72static void
 73validate_chandef_by_ht_vht_oper(struct ieee80211_sub_if_data *sdata,
 74				struct ieee80211_conn_settings *conn,
 75				u32 vht_cap_info,
 76				struct cfg80211_chan_def *chandef)
 77{
 78	u32 control_freq, center_freq1, center_freq2;
 79	enum nl80211_chan_width chan_width;
 80	struct ieee80211_ht_operation ht_oper;
 81	struct ieee80211_vht_operation vht_oper;
 82
 83	if (conn->mode < IEEE80211_CONN_MODE_HT ||
 84	    conn->bw_limit < IEEE80211_CONN_BW_LIMIT_40) {
 85		chandef->chan = NULL;
 86		return;
 87	}
 88
 89	control_freq = chandef->chan->center_freq;
 90	center_freq1 = chandef->center_freq1;
 91	center_freq2 = chandef->center_freq2;
 92	chan_width = chandef->width;
 93
 94	ht_oper.primary_chan = ieee80211_frequency_to_channel(control_freq);
 95	if (control_freq != center_freq1)
 96		ht_oper.ht_param = control_freq > center_freq1 ?
 97			IEEE80211_HT_PARAM_CHA_SEC_BELOW :
 98			IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
 99	else
100		ht_oper.ht_param = IEEE80211_HT_PARAM_CHA_SEC_NONE;
101
102	ieee80211_chandef_ht_oper(&ht_oper, chandef);
103
104	if (conn->mode < IEEE80211_CONN_MODE_VHT)
105		return;
106
107	vht_oper.center_freq_seg0_idx =
108		ieee80211_frequency_to_channel(center_freq1);
109	vht_oper.center_freq_seg1_idx = center_freq2 ?
110		ieee80211_frequency_to_channel(center_freq2) : 0;
111
112	switch (chan_width) {
113	case NL80211_CHAN_WIDTH_320:
114		WARN_ON(1);
115		break;
116	case NL80211_CHAN_WIDTH_160:
117		vht_oper.chan_width = IEEE80211_VHT_CHANWIDTH_80MHZ;
118		vht_oper.center_freq_seg1_idx = vht_oper.center_freq_seg0_idx;
119		vht_oper.center_freq_seg0_idx +=
120			control_freq < center_freq1 ? -8 : 8;
121		break;
122	case NL80211_CHAN_WIDTH_80P80:
123		vht_oper.chan_width = IEEE80211_VHT_CHANWIDTH_80MHZ;
124		break;
125	case NL80211_CHAN_WIDTH_80:
126		vht_oper.chan_width = IEEE80211_VHT_CHANWIDTH_80MHZ;
127		break;
128	default:
129		vht_oper.chan_width = IEEE80211_VHT_CHANWIDTH_USE_HT;
130		break;
131	}
132
133	ht_oper.operation_mode =
134		le16_encode_bits(vht_oper.center_freq_seg1_idx,
135				 IEEE80211_HT_OP_MODE_CCFS2_MASK);
136
137	if (!ieee80211_chandef_vht_oper(&sdata->local->hw, vht_cap_info,
138					&vht_oper, &ht_oper, chandef))
139		chandef->chan = NULL;
140}
141
142static void
143validate_chandef_by_6ghz_he_eht_oper(struct ieee80211_sub_if_data *sdata,
144				     struct ieee80211_conn_settings *conn,
145				     struct cfg80211_chan_def *chandef)
146{
147	struct ieee80211_local *local = sdata->local;
148	u32 control_freq, center_freq1, center_freq2;
149	enum nl80211_chan_width chan_width;
150	DEFINE_RAW_FLEX(struct ieee80211_he_operation, he, optional,
151			sizeof(struct ieee80211_he_6ghz_oper));
152	struct ieee80211_he_6ghz_oper *_6ghz_oper =
153				(struct ieee80211_he_6ghz_oper *)he->optional;
154	DEFINE_RAW_FLEX(struct ieee80211_eht_operation, eht, optional,
155			sizeof(struct ieee80211_eht_operation_info));
156	struct ieee80211_eht_operation_info *_oper_info =
157			(struct ieee80211_eht_operation_info *)eht->optional;
158	const struct ieee80211_eht_operation *eht_oper;
159
160	if (conn->mode < IEEE80211_CONN_MODE_HE) {
161		chandef->chan = NULL;
162		return;
163	}
164
165	control_freq = chandef->chan->center_freq;
166	center_freq1 = chandef->center_freq1;
167	center_freq2 = chandef->center_freq2;
168	chan_width = chandef->width;
169
170	he->he_oper_params =
171		le32_encode_bits(1, IEEE80211_HE_OPERATION_6GHZ_OP_INFO);
172	_6ghz_oper->primary =
173		ieee80211_frequency_to_channel(control_freq);
174	_6ghz_oper->ccfs0 = ieee80211_frequency_to_channel(center_freq1);
175	_6ghz_oper->ccfs1 = center_freq2 ?
176		ieee80211_frequency_to_channel(center_freq2) : 0;
177
178	switch (chan_width) {
179	case NL80211_CHAN_WIDTH_320:
180		_6ghz_oper->ccfs1 = _6ghz_oper->ccfs0;
181		_6ghz_oper->ccfs0 += control_freq < center_freq1 ? -16 : 16;
182		_6ghz_oper->control = IEEE80211_EHT_OPER_CHAN_WIDTH_320MHZ;
183		break;
184	case NL80211_CHAN_WIDTH_160:
185		_6ghz_oper->ccfs1 = _6ghz_oper->ccfs0;
186		_6ghz_oper->ccfs0 += control_freq < center_freq1 ? -8 : 8;
187		fallthrough;
188	case NL80211_CHAN_WIDTH_80P80:
189		_6ghz_oper->control =
190			IEEE80211_HE_6GHZ_OPER_CTRL_CHANWIDTH_160MHZ;
191		break;
192	case NL80211_CHAN_WIDTH_80:
193		_6ghz_oper->control =
194			IEEE80211_HE_6GHZ_OPER_CTRL_CHANWIDTH_80MHZ;
195		break;
196	case NL80211_CHAN_WIDTH_40:
197		_6ghz_oper->control =
198			IEEE80211_HE_6GHZ_OPER_CTRL_CHANWIDTH_40MHZ;
199		break;
200	default:
201		_6ghz_oper->control =
202			IEEE80211_HE_6GHZ_OPER_CTRL_CHANWIDTH_20MHZ;
203		break;
204	}
205
206	if (conn->mode < IEEE80211_CONN_MODE_EHT) {
207		eht_oper = NULL;
208	} else {
209		eht->params = IEEE80211_EHT_OPER_INFO_PRESENT;
210		_oper_info->control = _6ghz_oper->control;
211		_oper_info->ccfs0 = _6ghz_oper->ccfs0;
212		_oper_info->ccfs1 = _6ghz_oper->ccfs1;
213		eht_oper = eht;
214	}
215
216	if (!ieee80211_chandef_he_6ghz_oper(local, he, eht_oper, chandef))
217		chandef->chan = NULL;
218}
219
220int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata,
221				 struct ieee802_11_elems *elems,
222				 enum nl80211_band current_band,
223				 u32 vht_cap_info,
224				 struct ieee80211_conn_settings *conn,
225				 u8 *bssid, bool unprot_action,
226				 struct ieee80211_csa_ie *csa_ie)
227{
228	enum nl80211_band new_band = current_band;
229	int new_freq;
230	u8 new_chan_no = 0, new_op_class = 0;
231	struct ieee80211_channel *new_chan;
232	struct cfg80211_chan_def new_chandef = {};
233	const struct ieee80211_sec_chan_offs_ie *sec_chan_offs;
234	const struct ieee80211_wide_bw_chansw_ie *wide_bw_chansw_ie;
235	const struct ieee80211_bandwidth_indication *bwi;
236	const struct ieee80211_ext_chansw_ie *ext_chansw_elem;
237	int secondary_channel_offset = -1;
238
239	memset(csa_ie, 0, sizeof(*csa_ie));
240
241	sec_chan_offs = elems->sec_chan_offs;
242	wide_bw_chansw_ie = elems->wide_bw_chansw_ie;
243	bwi = elems->bandwidth_indication;
244	ext_chansw_elem = elems->ext_chansw_ie;
245
246	if (conn->mode < IEEE80211_CONN_MODE_HT ||
247	    conn->bw_limit < IEEE80211_CONN_BW_LIMIT_40) {
248		sec_chan_offs = NULL;
249		wide_bw_chansw_ie = NULL;
250	}
251
252	if (conn->mode < IEEE80211_CONN_MODE_VHT)
253		wide_bw_chansw_ie = NULL;
254
255	if (ext_chansw_elem) {
256		new_op_class = ext_chansw_elem->new_operating_class;
257
258		if (!ieee80211_operating_class_to_band(new_op_class, &new_band)) {
259			new_op_class = 0;
260			if (!unprot_action)
261				sdata_info(sdata,
262					   "cannot understand ECSA IE operating class, %d, ignoring\n",
263					   ext_chansw_elem->new_operating_class);
264		} else {
265			new_chan_no = ext_chansw_elem->new_ch_num;
266			csa_ie->count = ext_chansw_elem->count;
267			csa_ie->mode = ext_chansw_elem->mode;
268		}
269	}
270
271	if (!new_op_class && elems->ch_switch_ie) {
272		new_chan_no = elems->ch_switch_ie->new_ch_num;
273		csa_ie->count = elems->ch_switch_ie->count;
274		csa_ie->mode = elems->ch_switch_ie->mode;
275	}
276
277	/* nothing here we understand */
278	if (!new_chan_no)
279		return 1;
280
281	/* Mesh Channel Switch Parameters Element */
282	if (elems->mesh_chansw_params_ie) {
283		csa_ie->ttl = elems->mesh_chansw_params_ie->mesh_ttl;
284		csa_ie->mode = elems->mesh_chansw_params_ie->mesh_flags;
285		csa_ie->pre_value = le16_to_cpu(
286				elems->mesh_chansw_params_ie->mesh_pre_value);
287
288		if (elems->mesh_chansw_params_ie->mesh_flags &
289				WLAN_EID_CHAN_SWITCH_PARAM_REASON)
290			csa_ie->reason_code = le16_to_cpu(
291				elems->mesh_chansw_params_ie->mesh_reason);
292	}
293
294	new_freq = ieee80211_channel_to_frequency(new_chan_no, new_band);
295	new_chan = ieee80211_get_channel(sdata->local->hw.wiphy, new_freq);
296	if (!new_chan || new_chan->flags & IEEE80211_CHAN_DISABLED) {
297		if (!unprot_action)
298			sdata_info(sdata,
299				   "BSS %pM switches to unsupported channel (%d MHz), disconnecting\n",
300				   bssid, new_freq);
301		return -EINVAL;
302	}
303
304	if (sec_chan_offs) {
305		secondary_channel_offset = sec_chan_offs->sec_chan_offs;
306	} else if (conn->mode >= IEEE80211_CONN_MODE_HT) {
307		/* If the secondary channel offset IE is not present,
308		 * we can't know what's the post-CSA offset, so the
309		 * best we can do is use 20MHz.
310		*/
311		secondary_channel_offset = IEEE80211_HT_PARAM_CHA_SEC_NONE;
312	}
313
314	switch (secondary_channel_offset) {
315	default:
316		/* secondary_channel_offset was present but is invalid */
317	case IEEE80211_HT_PARAM_CHA_SEC_NONE:
318		cfg80211_chandef_create(&csa_ie->chanreq.oper, new_chan,
319					NL80211_CHAN_HT20);
320		break;
321	case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
322		cfg80211_chandef_create(&csa_ie->chanreq.oper, new_chan,
323					NL80211_CHAN_HT40PLUS);
324		break;
325	case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
326		cfg80211_chandef_create(&csa_ie->chanreq.oper, new_chan,
327					NL80211_CHAN_HT40MINUS);
328		break;
329	case -1:
330		cfg80211_chandef_create(&csa_ie->chanreq.oper, new_chan,
331					NL80211_CHAN_NO_HT);
332		/* keep width for 5/10 MHz channels */
333		switch (sdata->vif.bss_conf.chanreq.oper.width) {
334		case NL80211_CHAN_WIDTH_5:
335		case NL80211_CHAN_WIDTH_10:
336			csa_ie->chanreq.oper.width =
337				sdata->vif.bss_conf.chanreq.oper.width;
338			break;
339		default:
340			break;
341		}
342		break;
343	}
344
345	/* capture the AP configuration */
346	csa_ie->chanreq.ap = csa_ie->chanreq.oper;
347
348	/* parse one of the Elements to build a new chandef */
349	memset(&new_chandef, 0, sizeof(new_chandef));
350	new_chandef.chan = new_chan;
351	if (bwi) {
352		/* start with the CSA one */
353		new_chandef = csa_ie->chanreq.oper;
354		/* and update the width accordingly */
355		ieee80211_chandef_eht_oper(&bwi->info, &new_chandef);
356
357		if (bwi->params & IEEE80211_BW_IND_DIS_SUBCH_PRESENT)
358			new_chandef.punctured =
359				get_unaligned_le16(bwi->info.optional);
360	} else if (!wide_bw_chansw_ie || !wbcs_elem_to_chandef(wide_bw_chansw_ie,
361							       &new_chandef)) {
362		if (!ieee80211_operating_class_to_chandef(new_op_class, new_chan,
363							  &new_chandef))
364			new_chandef = csa_ie->chanreq.oper;
365	}
366
367	/* check if the new chandef fits the capabilities */
368	if (new_band == NL80211_BAND_6GHZ)
369		validate_chandef_by_6ghz_he_eht_oper(sdata, conn, &new_chandef);
370	else
371		validate_chandef_by_ht_vht_oper(sdata, conn, vht_cap_info,
372						&new_chandef);
373
374	/* if data is there validate the bandwidth & use it */
375	if (new_chandef.chan) {
376		/* capture the AP chandef before (potential) downgrading */
377		csa_ie->chanreq.ap = new_chandef;
378
379		while (conn->bw_limit <
380			       ieee80211_min_bw_limit_from_chandef(&new_chandef))
381			ieee80211_chandef_downgrade(&new_chandef, NULL);
382
383		if (!cfg80211_chandef_compatible(&new_chandef,
384						 &csa_ie->chanreq.oper)) {
385			sdata_info(sdata,
386				   "BSS %pM: CSA has inconsistent channel data, disconnecting\n",
387				   bssid);
388			return -EINVAL;
389		}
390
391		csa_ie->chanreq.oper = new_chandef;
392	}
393
394	if (elems->max_channel_switch_time)
395		csa_ie->max_switch_time =
396			(elems->max_channel_switch_time[0] << 0) |
397			(elems->max_channel_switch_time[1] <<  8) |
398			(elems->max_channel_switch_time[2] << 16);
399
400	return 0;
401}
402
403static void ieee80211_send_refuse_measurement_request(struct ieee80211_sub_if_data *sdata,
404					struct ieee80211_msrment_ie *request_ie,
405					const u8 *da, const u8 *bssid,
406					u8 dialog_token)
407{
408	struct ieee80211_local *local = sdata->local;
409	struct sk_buff *skb;
410	struct ieee80211_mgmt *msr_report;
411
412	skb = dev_alloc_skb(sizeof(*msr_report) + local->hw.extra_tx_headroom +
413				sizeof(struct ieee80211_msrment_ie));
414	if (!skb)
415		return;
416
417	skb_reserve(skb, local->hw.extra_tx_headroom);
418	msr_report = skb_put_zero(skb, 24);
419	memcpy(msr_report->da, da, ETH_ALEN);
420	memcpy(msr_report->sa, sdata->vif.addr, ETH_ALEN);
421	memcpy(msr_report->bssid, bssid, ETH_ALEN);
422	msr_report->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
423						IEEE80211_STYPE_ACTION);
424
425	skb_put(skb, 1 + sizeof(msr_report->u.action.u.measurement));
426	msr_report->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT;
427	msr_report->u.action.u.measurement.action_code =
428				WLAN_ACTION_SPCT_MSR_RPRT;
429	msr_report->u.action.u.measurement.dialog_token = dialog_token;
430
431	msr_report->u.action.u.measurement.element_id = WLAN_EID_MEASURE_REPORT;
432	msr_report->u.action.u.measurement.length =
433			sizeof(struct ieee80211_msrment_ie);
434
435	memset(&msr_report->u.action.u.measurement.msr_elem, 0,
436		sizeof(struct ieee80211_msrment_ie));
437	msr_report->u.action.u.measurement.msr_elem.token = request_ie->token;
438	msr_report->u.action.u.measurement.msr_elem.mode |=
439			IEEE80211_SPCT_MSR_RPRT_MODE_REFUSED;
440	msr_report->u.action.u.measurement.msr_elem.type = request_ie->type;
441
442	ieee80211_tx_skb(sdata, skb);
443}
444
445void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata,
446				       struct ieee80211_mgmt *mgmt,
447				       size_t len)
448{
449	/*
450	 * Ignoring measurement request is spec violation.
451	 * Mandatory measurements must be reported optional
452	 * measurements might be refused or reported incapable
453	 * For now just refuse
454	 * TODO: Answer basic measurement as unmeasured
455	 */
456	ieee80211_send_refuse_measurement_request(sdata,
457			&mgmt->u.action.u.measurement.msr_elem,
458			mgmt->sa, mgmt->bssid,
459			mgmt->u.action.u.measurement.dialog_token);
460}