xref: /linux/net/mac80211/tdls.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * mac80211 TDLS handling code
3  *
4  * Copyright 2006-2010	Johannes Berg <johannes@sipsolutions.net>
5  * Copyright 2014, Intel Corporation
6  * Copyright 2014  Intel Mobile Communications GmbH
7  * Copyright 2015  Intel Deutschland GmbH
8  *
9  * This file is GPLv2 as found in COPYING.
10  */
11 
12 #include <linux/ieee80211.h>
13 #include <linux/log2.h>
14 #include <net/cfg80211.h>
15 #include <linux/rtnetlink.h>
16 #include "ieee80211_i.h"
17 #include "driver-ops.h"
18 
19 /* give usermode some time for retries in setting up the TDLS session */
20 #define TDLS_PEER_SETUP_TIMEOUT	(15 * HZ)
21 
22 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
23 {
24 	struct ieee80211_sub_if_data *sdata;
25 	struct ieee80211_local *local;
26 
27 	sdata = container_of(wk, struct ieee80211_sub_if_data,
28 			     u.mgd.tdls_peer_del_work.work);
29 	local = sdata->local;
30 
31 	mutex_lock(&local->mtx);
32 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
33 		tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
34 		sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
35 		eth_zero_addr(sdata->u.mgd.tdls_peer);
36 	}
37 	mutex_unlock(&local->mtx);
38 }
39 
40 static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
41 					 struct sk_buff *skb)
42 {
43 	struct ieee80211_local *local = sdata->local;
44 	bool chan_switch = local->hw.wiphy->features &
45 			   NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
46 	bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW);
47 	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
48 	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
49 	bool vht = sband && sband->vht_cap.vht_supported;
50 	u8 *pos = (void *)skb_put(skb, 10);
51 
52 	*pos++ = WLAN_EID_EXT_CAPABILITY;
53 	*pos++ = 8; /* len */
54 	*pos++ = 0x0;
55 	*pos++ = 0x0;
56 	*pos++ = 0x0;
57 	*pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
58 	*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
59 	*pos++ = 0;
60 	*pos++ = 0;
61 	*pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
62 }
63 
64 static u8
65 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
66 			   struct sk_buff *skb, u16 start, u16 end,
67 			   u16 spacing)
68 {
69 	u8 subband_cnt = 0, ch_cnt = 0;
70 	struct ieee80211_channel *ch;
71 	struct cfg80211_chan_def chandef;
72 	int i, subband_start;
73 	struct wiphy *wiphy = sdata->local->hw.wiphy;
74 
75 	for (i = start; i <= end; i += spacing) {
76 		if (!ch_cnt)
77 			subband_start = i;
78 
79 		ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
80 		if (ch) {
81 			/* we will be active on the channel */
82 			cfg80211_chandef_create(&chandef, ch,
83 						NL80211_CHAN_NO_HT);
84 			if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
85 							  sdata->wdev.iftype)) {
86 				ch_cnt++;
87 				/*
88 				 * check if the next channel is also part of
89 				 * this allowed range
90 				 */
91 				continue;
92 			}
93 		}
94 
95 		/*
96 		 * we've reached the end of a range, with allowed channels
97 		 * found
98 		 */
99 		if (ch_cnt) {
100 			u8 *pos = skb_put(skb, 2);
101 			*pos++ = ieee80211_frequency_to_channel(subband_start);
102 			*pos++ = ch_cnt;
103 
104 			subband_cnt++;
105 			ch_cnt = 0;
106 		}
107 	}
108 
109 	/* all channels in the requested range are allowed - add them here */
110 	if (ch_cnt) {
111 		u8 *pos = skb_put(skb, 2);
112 		*pos++ = ieee80211_frequency_to_channel(subband_start);
113 		*pos++ = ch_cnt;
114 
115 		subband_cnt++;
116 	}
117 
118 	return subband_cnt;
119 }
120 
121 static void
122 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
123 				 struct sk_buff *skb)
124 {
125 	/*
126 	 * Add possible channels for TDLS. These are channels that are allowed
127 	 * to be active.
128 	 */
129 	u8 subband_cnt;
130 	u8 *pos = skb_put(skb, 2);
131 
132 	*pos++ = WLAN_EID_SUPPORTED_CHANNELS;
133 
134 	/*
135 	 * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
136 	 * this doesn't happen in real world scenarios.
137 	 */
138 
139 	/* 2GHz, with 5MHz spacing */
140 	subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
141 
142 	/* 5GHz, with 20MHz spacing */
143 	subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
144 
145 	/* length */
146 	*pos = 2 * subband_cnt;
147 }
148 
149 static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
150 					    struct sk_buff *skb)
151 {
152 	u8 *pos;
153 	u8 op_class;
154 
155 	if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
156 						  &op_class))
157 		return;
158 
159 	pos = skb_put(skb, 4);
160 	*pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
161 	*pos++ = 2; /* len */
162 
163 	*pos++ = op_class;
164 	*pos++ = op_class; /* give current operating class as alternate too */
165 }
166 
167 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
168 {
169 	u8 *pos = (void *)skb_put(skb, 3);
170 
171 	*pos++ = WLAN_EID_BSS_COEX_2040;
172 	*pos++ = 1; /* len */
173 
174 	*pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
175 }
176 
177 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
178 					u16 status_code)
179 {
180 	/* The capability will be 0 when sending a failure code */
181 	if (status_code != 0)
182 		return 0;
183 
184 	if (ieee80211_get_sdata_band(sdata) == IEEE80211_BAND_2GHZ) {
185 		return WLAN_CAPABILITY_SHORT_SLOT_TIME |
186 		       WLAN_CAPABILITY_SHORT_PREAMBLE;
187 	}
188 
189 	return 0;
190 }
191 
192 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
193 				       struct sk_buff *skb, const u8 *peer,
194 				       bool initiator)
195 {
196 	struct ieee80211_tdls_lnkie *lnkid;
197 	const u8 *init_addr, *rsp_addr;
198 
199 	if (initiator) {
200 		init_addr = sdata->vif.addr;
201 		rsp_addr = peer;
202 	} else {
203 		init_addr = peer;
204 		rsp_addr = sdata->vif.addr;
205 	}
206 
207 	lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
208 
209 	lnkid->ie_type = WLAN_EID_LINK_ID;
210 	lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
211 
212 	memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
213 	memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
214 	memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
215 }
216 
217 static void
218 ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
219 {
220 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
221 	u8 *pos = (void *)skb_put(skb, 4);
222 
223 	*pos++ = WLAN_EID_AID;
224 	*pos++ = 2; /* len */
225 	put_unaligned_le16(ifmgd->aid, pos);
226 }
227 
228 /* translate numbering in the WMM parameter IE to the mac80211 notation */
229 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
230 {
231 	switch (ac) {
232 	default:
233 		WARN_ON_ONCE(1);
234 	case 0:
235 		return IEEE80211_AC_BE;
236 	case 1:
237 		return IEEE80211_AC_BK;
238 	case 2:
239 		return IEEE80211_AC_VI;
240 	case 3:
241 		return IEEE80211_AC_VO;
242 	}
243 }
244 
245 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
246 {
247 	u8 ret;
248 
249 	ret = aifsn & 0x0f;
250 	if (acm)
251 		ret |= 0x10;
252 	ret |= (aci << 5) & 0x60;
253 	return ret;
254 }
255 
256 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
257 {
258 	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
259 	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
260 }
261 
262 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
263 					    struct sk_buff *skb)
264 {
265 	struct ieee80211_wmm_param_ie *wmm;
266 	struct ieee80211_tx_queue_params *txq;
267 	int i;
268 
269 	wmm = (void *)skb_put(skb, sizeof(*wmm));
270 	memset(wmm, 0, sizeof(*wmm));
271 
272 	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
273 	wmm->len = sizeof(*wmm) - 2;
274 
275 	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
276 	wmm->oui[1] = 0x50;
277 	wmm->oui[2] = 0xf2;
278 	wmm->oui_type = 2; /* WME */
279 	wmm->oui_subtype = 1; /* WME param */
280 	wmm->version = 1; /* WME ver */
281 	wmm->qos_info = 0; /* U-APSD not in use */
282 
283 	/*
284 	 * Use the EDCA parameters defined for the BSS, or default if the AP
285 	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
286 	 */
287 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
288 		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
289 		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
290 							       txq->acm, i);
291 		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
292 		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
293 	}
294 }
295 
296 static void
297 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
298 				   struct sta_info *sta)
299 {
300 	/* IEEE802.11ac-2013 Table E-4 */
301 	u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
302 	struct cfg80211_chan_def uc = sta->tdls_chandef;
303 	enum nl80211_chan_width max_width = ieee80211_get_sta_bw(&sta->sta);
304 	int i;
305 
306 	/* only support upgrading non-narrow channels up to 80Mhz */
307 	if (max_width == NL80211_CHAN_WIDTH_5 ||
308 	    max_width == NL80211_CHAN_WIDTH_10)
309 		return;
310 
311 	if (max_width > NL80211_CHAN_WIDTH_80)
312 		max_width = NL80211_CHAN_WIDTH_80;
313 
314 	if (uc.width == max_width)
315 		return;
316 	/*
317 	 * Channel usage constrains in the IEEE802.11ac-2013 specification only
318 	 * allow expanding a 20MHz channel to 80MHz in a single way. In
319 	 * addition, there are no 40MHz allowed channels that are not part of
320 	 * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
321 	 */
322 	for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
323 		if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
324 			uc.center_freq1 = centers_80mhz[i];
325 			uc.width = NL80211_CHAN_WIDTH_80;
326 			break;
327 		}
328 
329 	if (!uc.center_freq1)
330 		return;
331 
332 	/* proceed to downgrade the chandef until usable or the same */
333 	while (uc.width > max_width &&
334 	       !cfg80211_reg_can_beacon(sdata->local->hw.wiphy,
335 					&uc, sdata->wdev.iftype))
336 		ieee80211_chandef_downgrade(&uc);
337 
338 	if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
339 		tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
340 			 sta->tdls_chandef.width, uc.width);
341 
342 		/*
343 		 * the station is not yet authorized when BW upgrade is done,
344 		 * locking is not required
345 		 */
346 		sta->tdls_chandef = uc;
347 	}
348 }
349 
350 static void
351 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
352 				   struct sk_buff *skb, const u8 *peer,
353 				   u8 action_code, bool initiator,
354 				   const u8 *extra_ies, size_t extra_ies_len)
355 {
356 	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
357 	struct ieee80211_local *local = sdata->local;
358 	struct ieee80211_supported_band *sband;
359 	struct ieee80211_sta_ht_cap ht_cap;
360 	struct ieee80211_sta_vht_cap vht_cap;
361 	struct sta_info *sta = NULL;
362 	size_t offset = 0, noffset;
363 	u8 *pos;
364 
365 	ieee80211_add_srates_ie(sdata, skb, false, band);
366 	ieee80211_add_ext_srates_ie(sdata, skb, false, band);
367 	ieee80211_tdls_add_supp_channels(sdata, skb);
368 
369 	/* add any custom IEs that go before Extended Capabilities */
370 	if (extra_ies_len) {
371 		static const u8 before_ext_cap[] = {
372 			WLAN_EID_SUPP_RATES,
373 			WLAN_EID_COUNTRY,
374 			WLAN_EID_EXT_SUPP_RATES,
375 			WLAN_EID_SUPPORTED_CHANNELS,
376 			WLAN_EID_RSN,
377 		};
378 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
379 					     before_ext_cap,
380 					     ARRAY_SIZE(before_ext_cap),
381 					     offset);
382 		pos = skb_put(skb, noffset - offset);
383 		memcpy(pos, extra_ies + offset, noffset - offset);
384 		offset = noffset;
385 	}
386 
387 	ieee80211_tdls_add_ext_capab(sdata, skb);
388 
389 	/* add the QoS element if we support it */
390 	if (local->hw.queues >= IEEE80211_NUM_ACS &&
391 	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
392 		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
393 
394 	/* add any custom IEs that go before HT capabilities */
395 	if (extra_ies_len) {
396 		static const u8 before_ht_cap[] = {
397 			WLAN_EID_SUPP_RATES,
398 			WLAN_EID_COUNTRY,
399 			WLAN_EID_EXT_SUPP_RATES,
400 			WLAN_EID_SUPPORTED_CHANNELS,
401 			WLAN_EID_RSN,
402 			WLAN_EID_EXT_CAPABILITY,
403 			WLAN_EID_QOS_CAPA,
404 			WLAN_EID_FAST_BSS_TRANSITION,
405 			WLAN_EID_TIMEOUT_INTERVAL,
406 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
407 		};
408 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
409 					     before_ht_cap,
410 					     ARRAY_SIZE(before_ht_cap),
411 					     offset);
412 		pos = skb_put(skb, noffset - offset);
413 		memcpy(pos, extra_ies + offset, noffset - offset);
414 		offset = noffset;
415 	}
416 
417 	mutex_lock(&local->sta_mtx);
418 
419 	/* we should have the peer STA if we're already responding */
420 	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
421 		sta = sta_info_get(sdata, peer);
422 		if (WARN_ON_ONCE(!sta)) {
423 			mutex_unlock(&local->sta_mtx);
424 			return;
425 		}
426 
427 		sta->tdls_chandef = sdata->vif.bss_conf.chandef;
428 	}
429 
430 	ieee80211_tdls_add_oper_classes(sdata, skb);
431 
432 	/*
433 	 * with TDLS we can switch channels, and HT-caps are not necessarily
434 	 * the same on all bands. The specification limits the setup to a
435 	 * single HT-cap, so use the current band for now.
436 	 */
437 	sband = local->hw.wiphy->bands[band];
438 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
439 
440 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
441 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
442 	    ht_cap.ht_supported) {
443 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
444 
445 		/* disable SMPS in TDLS initiator */
446 		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
447 				<< IEEE80211_HT_CAP_SM_PS_SHIFT;
448 
449 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
450 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
451 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
452 		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
453 		/* the peer caps are already intersected with our own */
454 		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
455 
456 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
457 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
458 	}
459 
460 	if (ht_cap.ht_supported &&
461 	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
462 		ieee80211_tdls_add_bss_coex_ie(skb);
463 
464 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
465 
466 	/* add any custom IEs that go before VHT capabilities */
467 	if (extra_ies_len) {
468 		static const u8 before_vht_cap[] = {
469 			WLAN_EID_SUPP_RATES,
470 			WLAN_EID_COUNTRY,
471 			WLAN_EID_EXT_SUPP_RATES,
472 			WLAN_EID_SUPPORTED_CHANNELS,
473 			WLAN_EID_RSN,
474 			WLAN_EID_EXT_CAPABILITY,
475 			WLAN_EID_QOS_CAPA,
476 			WLAN_EID_FAST_BSS_TRANSITION,
477 			WLAN_EID_TIMEOUT_INTERVAL,
478 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
479 			WLAN_EID_MULTI_BAND,
480 		};
481 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
482 					     before_vht_cap,
483 					     ARRAY_SIZE(before_vht_cap),
484 					     offset);
485 		pos = skb_put(skb, noffset - offset);
486 		memcpy(pos, extra_ies + offset, noffset - offset);
487 		offset = noffset;
488 	}
489 
490 	/* build the VHT-cap similarly to the HT-cap */
491 	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
492 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
493 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
494 	    vht_cap.vht_supported) {
495 		ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
496 
497 		/* the AID is present only when VHT is implemented */
498 		if (action_code == WLAN_TDLS_SETUP_REQUEST)
499 			ieee80211_tdls_add_aid(sdata, skb);
500 
501 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
502 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
503 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
504 		   vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
505 		/* the peer caps are already intersected with our own */
506 		memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
507 
508 		/* the AID is present only when VHT is implemented */
509 		ieee80211_tdls_add_aid(sdata, skb);
510 
511 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
512 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
513 
514 		/*
515 		 * if both peers support WIDER_BW, we can expand the chandef to
516 		 * a wider compatible one, up to 80MHz
517 		 */
518 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
519 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
520 	}
521 
522 	mutex_unlock(&local->sta_mtx);
523 
524 	/* add any remaining IEs */
525 	if (extra_ies_len) {
526 		noffset = extra_ies_len;
527 		pos = skb_put(skb, noffset - offset);
528 		memcpy(pos, extra_ies + offset, noffset - offset);
529 	}
530 
531 }
532 
533 static void
534 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
535 				 struct sk_buff *skb, const u8 *peer,
536 				 bool initiator, const u8 *extra_ies,
537 				 size_t extra_ies_len)
538 {
539 	struct ieee80211_local *local = sdata->local;
540 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
541 	size_t offset = 0, noffset;
542 	struct sta_info *sta, *ap_sta;
543 	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
544 	u8 *pos;
545 
546 	mutex_lock(&local->sta_mtx);
547 
548 	sta = sta_info_get(sdata, peer);
549 	ap_sta = sta_info_get(sdata, ifmgd->bssid);
550 	if (WARN_ON_ONCE(!sta || !ap_sta)) {
551 		mutex_unlock(&local->sta_mtx);
552 		return;
553 	}
554 
555 	sta->tdls_chandef = sdata->vif.bss_conf.chandef;
556 
557 	/* add any custom IEs that go before the QoS IE */
558 	if (extra_ies_len) {
559 		static const u8 before_qos[] = {
560 			WLAN_EID_RSN,
561 		};
562 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
563 					     before_qos,
564 					     ARRAY_SIZE(before_qos),
565 					     offset);
566 		pos = skb_put(skb, noffset - offset);
567 		memcpy(pos, extra_ies + offset, noffset - offset);
568 		offset = noffset;
569 	}
570 
571 	/* add the QoS param IE if both the peer and we support it */
572 	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
573 		ieee80211_tdls_add_wmm_param_ie(sdata, skb);
574 
575 	/* add any custom IEs that go before HT operation */
576 	if (extra_ies_len) {
577 		static const u8 before_ht_op[] = {
578 			WLAN_EID_RSN,
579 			WLAN_EID_QOS_CAPA,
580 			WLAN_EID_FAST_BSS_TRANSITION,
581 			WLAN_EID_TIMEOUT_INTERVAL,
582 		};
583 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
584 					     before_ht_op,
585 					     ARRAY_SIZE(before_ht_op),
586 					     offset);
587 		pos = skb_put(skb, noffset - offset);
588 		memcpy(pos, extra_ies + offset, noffset - offset);
589 		offset = noffset;
590 	}
591 
592 	/* if HT support is only added in TDLS, we need an HT-operation IE */
593 	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
594 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
595 		/* send an empty HT operation IE */
596 		ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
597 					   &sdata->vif.bss_conf.chandef, 0);
598 	}
599 
600 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
601 
602 	/* only include VHT-operation if not on the 2.4GHz band */
603 	if (band != IEEE80211_BAND_2GHZ && sta->sta.vht_cap.vht_supported) {
604 		/*
605 		 * if both peers support WIDER_BW, we can expand the chandef to
606 		 * a wider compatible one, up to 80MHz
607 		 */
608 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
609 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
610 
611 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
612 		ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
613 					    &sta->tdls_chandef);
614 	}
615 
616 	mutex_unlock(&local->sta_mtx);
617 
618 	/* add any remaining IEs */
619 	if (extra_ies_len) {
620 		noffset = extra_ies_len;
621 		pos = skb_put(skb, noffset - offset);
622 		memcpy(pos, extra_ies + offset, noffset - offset);
623 	}
624 }
625 
626 static void
627 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
628 				       struct sk_buff *skb, const u8 *peer,
629 				       bool initiator, const u8 *extra_ies,
630 				       size_t extra_ies_len, u8 oper_class,
631 				       struct cfg80211_chan_def *chandef)
632 {
633 	struct ieee80211_tdls_data *tf;
634 	size_t offset = 0, noffset;
635 	u8 *pos;
636 
637 	if (WARN_ON_ONCE(!chandef))
638 		return;
639 
640 	tf = (void *)skb->data;
641 	tf->u.chan_switch_req.target_channel =
642 		ieee80211_frequency_to_channel(chandef->chan->center_freq);
643 	tf->u.chan_switch_req.oper_class = oper_class;
644 
645 	if (extra_ies_len) {
646 		static const u8 before_lnkie[] = {
647 			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
648 		};
649 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
650 					     before_lnkie,
651 					     ARRAY_SIZE(before_lnkie),
652 					     offset);
653 		pos = skb_put(skb, noffset - offset);
654 		memcpy(pos, extra_ies + offset, noffset - offset);
655 		offset = noffset;
656 	}
657 
658 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
659 
660 	/* add any remaining IEs */
661 	if (extra_ies_len) {
662 		noffset = extra_ies_len;
663 		pos = skb_put(skb, noffset - offset);
664 		memcpy(pos, extra_ies + offset, noffset - offset);
665 	}
666 }
667 
668 static void
669 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
670 					struct sk_buff *skb, const u8 *peer,
671 					u16 status_code, bool initiator,
672 					const u8 *extra_ies,
673 					size_t extra_ies_len)
674 {
675 	if (status_code == 0)
676 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
677 
678 	if (extra_ies_len)
679 		memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
680 }
681 
682 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
683 				   struct sk_buff *skb, const u8 *peer,
684 				   u8 action_code, u16 status_code,
685 				   bool initiator, const u8 *extra_ies,
686 				   size_t extra_ies_len, u8 oper_class,
687 				   struct cfg80211_chan_def *chandef)
688 {
689 	switch (action_code) {
690 	case WLAN_TDLS_SETUP_REQUEST:
691 	case WLAN_TDLS_SETUP_RESPONSE:
692 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
693 		if (status_code == 0)
694 			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
695 							   action_code,
696 							   initiator,
697 							   extra_ies,
698 							   extra_ies_len);
699 		break;
700 	case WLAN_TDLS_SETUP_CONFIRM:
701 		if (status_code == 0)
702 			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
703 							 initiator, extra_ies,
704 							 extra_ies_len);
705 		break;
706 	case WLAN_TDLS_TEARDOWN:
707 	case WLAN_TDLS_DISCOVERY_REQUEST:
708 		if (extra_ies_len)
709 			memcpy(skb_put(skb, extra_ies_len), extra_ies,
710 			       extra_ies_len);
711 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
712 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
713 		break;
714 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
715 		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
716 						       initiator, extra_ies,
717 						       extra_ies_len,
718 						       oper_class, chandef);
719 		break;
720 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
721 		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
722 							status_code,
723 							initiator, extra_ies,
724 							extra_ies_len);
725 		break;
726 	}
727 
728 }
729 
730 static int
731 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
732 			       const u8 *peer, u8 action_code, u8 dialog_token,
733 			       u16 status_code, struct sk_buff *skb)
734 {
735 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
736 	struct ieee80211_tdls_data *tf;
737 
738 	tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
739 
740 	memcpy(tf->da, peer, ETH_ALEN);
741 	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
742 	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
743 	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
744 
745 	/* network header is after the ethernet header */
746 	skb_set_network_header(skb, ETH_HLEN);
747 
748 	switch (action_code) {
749 	case WLAN_TDLS_SETUP_REQUEST:
750 		tf->category = WLAN_CATEGORY_TDLS;
751 		tf->action_code = WLAN_TDLS_SETUP_REQUEST;
752 
753 		skb_put(skb, sizeof(tf->u.setup_req));
754 		tf->u.setup_req.dialog_token = dialog_token;
755 		tf->u.setup_req.capability =
756 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
757 								 status_code));
758 		break;
759 	case WLAN_TDLS_SETUP_RESPONSE:
760 		tf->category = WLAN_CATEGORY_TDLS;
761 		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
762 
763 		skb_put(skb, sizeof(tf->u.setup_resp));
764 		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
765 		tf->u.setup_resp.dialog_token = dialog_token;
766 		tf->u.setup_resp.capability =
767 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
768 								 status_code));
769 		break;
770 	case WLAN_TDLS_SETUP_CONFIRM:
771 		tf->category = WLAN_CATEGORY_TDLS;
772 		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
773 
774 		skb_put(skb, sizeof(tf->u.setup_cfm));
775 		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
776 		tf->u.setup_cfm.dialog_token = dialog_token;
777 		break;
778 	case WLAN_TDLS_TEARDOWN:
779 		tf->category = WLAN_CATEGORY_TDLS;
780 		tf->action_code = WLAN_TDLS_TEARDOWN;
781 
782 		skb_put(skb, sizeof(tf->u.teardown));
783 		tf->u.teardown.reason_code = cpu_to_le16(status_code);
784 		break;
785 	case WLAN_TDLS_DISCOVERY_REQUEST:
786 		tf->category = WLAN_CATEGORY_TDLS;
787 		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
788 
789 		skb_put(skb, sizeof(tf->u.discover_req));
790 		tf->u.discover_req.dialog_token = dialog_token;
791 		break;
792 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
793 		tf->category = WLAN_CATEGORY_TDLS;
794 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
795 
796 		skb_put(skb, sizeof(tf->u.chan_switch_req));
797 		break;
798 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
799 		tf->category = WLAN_CATEGORY_TDLS;
800 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
801 
802 		skb_put(skb, sizeof(tf->u.chan_switch_resp));
803 		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
804 		break;
805 	default:
806 		return -EINVAL;
807 	}
808 
809 	return 0;
810 }
811 
812 static int
813 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
814 			   const u8 *peer, u8 action_code, u8 dialog_token,
815 			   u16 status_code, struct sk_buff *skb)
816 {
817 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
818 	struct ieee80211_mgmt *mgmt;
819 
820 	mgmt = (void *)skb_put(skb, 24);
821 	memset(mgmt, 0, 24);
822 	memcpy(mgmt->da, peer, ETH_ALEN);
823 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
824 	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
825 
826 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
827 					  IEEE80211_STYPE_ACTION);
828 
829 	switch (action_code) {
830 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
831 		skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
832 		mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
833 		mgmt->u.action.u.tdls_discover_resp.action_code =
834 			WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
835 		mgmt->u.action.u.tdls_discover_resp.dialog_token =
836 			dialog_token;
837 		mgmt->u.action.u.tdls_discover_resp.capability =
838 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
839 								 status_code));
840 		break;
841 	default:
842 		return -EINVAL;
843 	}
844 
845 	return 0;
846 }
847 
848 static struct sk_buff *
849 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
850 				      const u8 *peer, u8 action_code,
851 				      u8 dialog_token, u16 status_code,
852 				      bool initiator, const u8 *extra_ies,
853 				      size_t extra_ies_len, u8 oper_class,
854 				      struct cfg80211_chan_def *chandef)
855 {
856 	struct ieee80211_local *local = sdata->local;
857 	struct sk_buff *skb;
858 	int ret;
859 
860 	skb = netdev_alloc_skb(sdata->dev,
861 			       local->hw.extra_tx_headroom +
862 			       max(sizeof(struct ieee80211_mgmt),
863 				   sizeof(struct ieee80211_tdls_data)) +
864 			       50 + /* supported rates */
865 			       10 + /* ext capab */
866 			       26 + /* max(WMM-info, WMM-param) */
867 			       2 + max(sizeof(struct ieee80211_ht_cap),
868 				       sizeof(struct ieee80211_ht_operation)) +
869 			       2 + max(sizeof(struct ieee80211_vht_cap),
870 				       sizeof(struct ieee80211_vht_operation)) +
871 			       50 + /* supported channels */
872 			       3 + /* 40/20 BSS coex */
873 			       4 + /* AID */
874 			       4 + /* oper classes */
875 			       extra_ies_len +
876 			       sizeof(struct ieee80211_tdls_lnkie));
877 	if (!skb)
878 		return NULL;
879 
880 	skb_reserve(skb, local->hw.extra_tx_headroom);
881 
882 	switch (action_code) {
883 	case WLAN_TDLS_SETUP_REQUEST:
884 	case WLAN_TDLS_SETUP_RESPONSE:
885 	case WLAN_TDLS_SETUP_CONFIRM:
886 	case WLAN_TDLS_TEARDOWN:
887 	case WLAN_TDLS_DISCOVERY_REQUEST:
888 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
889 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
890 		ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
891 						     sdata->dev, peer,
892 						     action_code, dialog_token,
893 						     status_code, skb);
894 		break;
895 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
896 		ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
897 						 peer, action_code,
898 						 dialog_token, status_code,
899 						 skb);
900 		break;
901 	default:
902 		ret = -ENOTSUPP;
903 		break;
904 	}
905 
906 	if (ret < 0)
907 		goto fail;
908 
909 	ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
910 			       initiator, extra_ies, extra_ies_len, oper_class,
911 			       chandef);
912 	return skb;
913 
914 fail:
915 	dev_kfree_skb(skb);
916 	return NULL;
917 }
918 
919 static int
920 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
921 				const u8 *peer, u8 action_code, u8 dialog_token,
922 				u16 status_code, u32 peer_capability,
923 				bool initiator, const u8 *extra_ies,
924 				size_t extra_ies_len, u8 oper_class,
925 				struct cfg80211_chan_def *chandef)
926 {
927 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
928 	struct sk_buff *skb = NULL;
929 	struct sta_info *sta;
930 	u32 flags = 0;
931 	int ret = 0;
932 
933 	rcu_read_lock();
934 	sta = sta_info_get(sdata, peer);
935 
936 	/* infer the initiator if we can, to support old userspace */
937 	switch (action_code) {
938 	case WLAN_TDLS_SETUP_REQUEST:
939 		if (sta) {
940 			set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
941 			sta->sta.tdls_initiator = false;
942 		}
943 		/* fall-through */
944 	case WLAN_TDLS_SETUP_CONFIRM:
945 	case WLAN_TDLS_DISCOVERY_REQUEST:
946 		initiator = true;
947 		break;
948 	case WLAN_TDLS_SETUP_RESPONSE:
949 		/*
950 		 * In some testing scenarios, we send a request and response.
951 		 * Make the last packet sent take effect for the initiator
952 		 * value.
953 		 */
954 		if (sta) {
955 			clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
956 			sta->sta.tdls_initiator = true;
957 		}
958 		/* fall-through */
959 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
960 		initiator = false;
961 		break;
962 	case WLAN_TDLS_TEARDOWN:
963 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
964 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
965 		/* any value is ok */
966 		break;
967 	default:
968 		ret = -ENOTSUPP;
969 		break;
970 	}
971 
972 	if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
973 		initiator = true;
974 
975 	rcu_read_unlock();
976 	if (ret < 0)
977 		goto fail;
978 
979 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
980 						    dialog_token, status_code,
981 						    initiator, extra_ies,
982 						    extra_ies_len, oper_class,
983 						    chandef);
984 	if (!skb) {
985 		ret = -EINVAL;
986 		goto fail;
987 	}
988 
989 	if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
990 		ieee80211_tx_skb(sdata, skb);
991 		return 0;
992 	}
993 
994 	/*
995 	 * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
996 	 * we should default to AC_VI.
997 	 */
998 	switch (action_code) {
999 	case WLAN_TDLS_SETUP_REQUEST:
1000 	case WLAN_TDLS_SETUP_RESPONSE:
1001 		skb_set_queue_mapping(skb, IEEE80211_AC_BK);
1002 		skb->priority = 2;
1003 		break;
1004 	default:
1005 		skb_set_queue_mapping(skb, IEEE80211_AC_VI);
1006 		skb->priority = 5;
1007 		break;
1008 	}
1009 
1010 	/*
1011 	 * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
1012 	 * Later, if no ACK is returned from peer, we will re-send the teardown
1013 	 * packet through the AP.
1014 	 */
1015 	if ((action_code == WLAN_TDLS_TEARDOWN) &&
1016 	    ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
1017 		bool try_resend; /* Should we keep skb for possible resend */
1018 
1019 		/* If not sending directly to peer - no point in keeping skb */
1020 		rcu_read_lock();
1021 		sta = sta_info_get(sdata, peer);
1022 		try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1023 		rcu_read_unlock();
1024 
1025 		spin_lock_bh(&sdata->u.mgd.teardown_lock);
1026 		if (try_resend && !sdata->u.mgd.teardown_skb) {
1027 			/* Mark it as requiring TX status callback  */
1028 			flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
1029 				 IEEE80211_TX_INTFL_MLME_CONN_TX;
1030 
1031 			/*
1032 			 * skb is copied since mac80211 will later set
1033 			 * properties that might not be the same as the AP,
1034 			 * such as encryption, QoS, addresses, etc.
1035 			 *
1036 			 * No problem if skb_copy() fails, so no need to check.
1037 			 */
1038 			sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
1039 			sdata->u.mgd.orig_teardown_skb = skb;
1040 		}
1041 		spin_unlock_bh(&sdata->u.mgd.teardown_lock);
1042 	}
1043 
1044 	/* disable bottom halves when entering the Tx path */
1045 	local_bh_disable();
1046 	__ieee80211_subif_start_xmit(skb, dev, flags);
1047 	local_bh_enable();
1048 
1049 	return ret;
1050 
1051 fail:
1052 	dev_kfree_skb(skb);
1053 	return ret;
1054 }
1055 
1056 static int
1057 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
1058 			  const u8 *peer, u8 action_code, u8 dialog_token,
1059 			  u16 status_code, u32 peer_capability, bool initiator,
1060 			  const u8 *extra_ies, size_t extra_ies_len)
1061 {
1062 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1063 	struct ieee80211_local *local = sdata->local;
1064 	enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
1065 	int ret;
1066 
1067 	/* don't support setup with forced SMPS mode that's not off */
1068 	if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
1069 	    smps_mode != IEEE80211_SMPS_OFF) {
1070 		tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
1071 			 smps_mode);
1072 		return -ENOTSUPP;
1073 	}
1074 
1075 	mutex_lock(&local->mtx);
1076 
1077 	/* we don't support concurrent TDLS peer setups */
1078 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
1079 	    !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1080 		ret = -EBUSY;
1081 		goto out_unlock;
1082 	}
1083 
1084 	/*
1085 	 * make sure we have a STA representing the peer so we drop or buffer
1086 	 * non-TDLS-setup frames to the peer. We can't send other packets
1087 	 * during setup through the AP path.
1088 	 * Allow error packets to be sent - sometimes we don't even add a STA
1089 	 * before failing the setup.
1090 	 */
1091 	if (status_code == 0) {
1092 		rcu_read_lock();
1093 		if (!sta_info_get(sdata, peer)) {
1094 			rcu_read_unlock();
1095 			ret = -ENOLINK;
1096 			goto out_unlock;
1097 		}
1098 		rcu_read_unlock();
1099 	}
1100 
1101 	ieee80211_flush_queues(local, sdata, false);
1102 	memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
1103 	mutex_unlock(&local->mtx);
1104 
1105 	/* we cannot take the mutex while preparing the setup packet */
1106 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1107 					      dialog_token, status_code,
1108 					      peer_capability, initiator,
1109 					      extra_ies, extra_ies_len, 0,
1110 					      NULL);
1111 	if (ret < 0) {
1112 		mutex_lock(&local->mtx);
1113 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1114 		mutex_unlock(&local->mtx);
1115 		return ret;
1116 	}
1117 
1118 	ieee80211_queue_delayed_work(&sdata->local->hw,
1119 				     &sdata->u.mgd.tdls_peer_del_work,
1120 				     TDLS_PEER_SETUP_TIMEOUT);
1121 	return 0;
1122 
1123 out_unlock:
1124 	mutex_unlock(&local->mtx);
1125 	return ret;
1126 }
1127 
1128 static int
1129 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
1130 			     const u8 *peer, u8 action_code, u8 dialog_token,
1131 			     u16 status_code, u32 peer_capability,
1132 			     bool initiator, const u8 *extra_ies,
1133 			     size_t extra_ies_len)
1134 {
1135 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1136 	struct ieee80211_local *local = sdata->local;
1137 	struct sta_info *sta;
1138 	int ret;
1139 
1140 	/*
1141 	 * No packets can be transmitted to the peer via the AP during setup -
1142 	 * the STA is set as a TDLS peer, but is not authorized.
1143 	 * During teardown, we prevent direct transmissions by stopping the
1144 	 * queues and flushing all direct packets.
1145 	 */
1146 	ieee80211_stop_vif_queues(local, sdata,
1147 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1148 	ieee80211_flush_queues(local, sdata, false);
1149 
1150 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1151 					      dialog_token, status_code,
1152 					      peer_capability, initiator,
1153 					      extra_ies, extra_ies_len, 0,
1154 					      NULL);
1155 	if (ret < 0)
1156 		sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
1157 			  ret);
1158 
1159 	/*
1160 	 * Remove the STA AUTH flag to force further traffic through the AP. If
1161 	 * the STA was unreachable, it was already removed.
1162 	 */
1163 	rcu_read_lock();
1164 	sta = sta_info_get(sdata, peer);
1165 	if (sta)
1166 		clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1167 	rcu_read_unlock();
1168 
1169 	ieee80211_wake_vif_queues(local, sdata,
1170 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1171 
1172 	return 0;
1173 }
1174 
1175 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
1176 			const u8 *peer, u8 action_code, u8 dialog_token,
1177 			u16 status_code, u32 peer_capability,
1178 			bool initiator, const u8 *extra_ies,
1179 			size_t extra_ies_len)
1180 {
1181 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1182 	int ret;
1183 
1184 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1185 		return -ENOTSUPP;
1186 
1187 	/* make sure we are in managed mode, and associated */
1188 	if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1189 	    !sdata->u.mgd.associated)
1190 		return -EINVAL;
1191 
1192 	switch (action_code) {
1193 	case WLAN_TDLS_SETUP_REQUEST:
1194 	case WLAN_TDLS_SETUP_RESPONSE:
1195 		ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1196 						dialog_token, status_code,
1197 						peer_capability, initiator,
1198 						extra_ies, extra_ies_len);
1199 		break;
1200 	case WLAN_TDLS_TEARDOWN:
1201 		ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1202 						   action_code, dialog_token,
1203 						   status_code,
1204 						   peer_capability, initiator,
1205 						   extra_ies, extra_ies_len);
1206 		break;
1207 	case WLAN_TDLS_DISCOVERY_REQUEST:
1208 		/*
1209 		 * Protect the discovery so we can hear the TDLS discovery
1210 		 * response frame. It is transmitted directly and not buffered
1211 		 * by the AP.
1212 		 */
1213 		drv_mgd_protect_tdls_discover(sdata->local, sdata);
1214 		/* fall-through */
1215 	case WLAN_TDLS_SETUP_CONFIRM:
1216 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1217 		/* no special handling */
1218 		ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1219 						      action_code,
1220 						      dialog_token,
1221 						      status_code,
1222 						      peer_capability,
1223 						      initiator, extra_ies,
1224 						      extra_ies_len, 0, NULL);
1225 		break;
1226 	default:
1227 		ret = -EOPNOTSUPP;
1228 		break;
1229 	}
1230 
1231 	tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1232 		 action_code, peer, ret);
1233 	return ret;
1234 }
1235 
1236 static void iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data *sdata)
1237 {
1238 	struct ieee80211_local *local = sdata->local;
1239 	struct ieee80211_chanctx_conf *conf;
1240 	struct ieee80211_chanctx *ctx;
1241 
1242 	mutex_lock(&local->chanctx_mtx);
1243 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1244 					 lockdep_is_held(&local->chanctx_mtx));
1245 	if (conf) {
1246 		ctx = container_of(conf, struct ieee80211_chanctx, conf);
1247 		ieee80211_recalc_chanctx_chantype(local, ctx);
1248 	}
1249 	mutex_unlock(&local->chanctx_mtx);
1250 }
1251 
1252 static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
1253 {
1254 	struct sta_info *sta;
1255 	bool result = false;
1256 
1257 	rcu_read_lock();
1258 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1259 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1260 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
1261 		    !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
1262 		    !sta->sta.ht_cap.ht_supported)
1263 			continue;
1264 		result = true;
1265 		break;
1266 	}
1267 	rcu_read_unlock();
1268 
1269 	return result;
1270 }
1271 
1272 static void
1273 iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
1274 				   struct sta_info *sta)
1275 {
1276 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
1277 	bool tdls_ht;
1278 	u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
1279 			 IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
1280 			 IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
1281 	u16 opmode;
1282 
1283 	/* Nothing to do if the BSS connection uses HT */
1284 	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
1285 		return;
1286 
1287 	tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
1288 		  iee80211_tdls_have_ht_peers(sdata);
1289 
1290 	opmode = sdata->vif.bss_conf.ht_operation_mode;
1291 
1292 	if (tdls_ht)
1293 		opmode |= protection;
1294 	else
1295 		opmode &= ~protection;
1296 
1297 	if (opmode == sdata->vif.bss_conf.ht_operation_mode)
1298 		return;
1299 
1300 	sdata->vif.bss_conf.ht_operation_mode = opmode;
1301 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
1302 }
1303 
1304 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1305 			const u8 *peer, enum nl80211_tdls_operation oper)
1306 {
1307 	struct sta_info *sta;
1308 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1309 	struct ieee80211_local *local = sdata->local;
1310 	int ret;
1311 
1312 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1313 		return -ENOTSUPP;
1314 
1315 	if (sdata->vif.type != NL80211_IFTYPE_STATION)
1316 		return -EINVAL;
1317 
1318 	switch (oper) {
1319 	case NL80211_TDLS_ENABLE_LINK:
1320 	case NL80211_TDLS_DISABLE_LINK:
1321 		break;
1322 	case NL80211_TDLS_TEARDOWN:
1323 	case NL80211_TDLS_SETUP:
1324 	case NL80211_TDLS_DISCOVERY_REQ:
1325 		/* We don't support in-driver setup/teardown/discovery */
1326 		return -ENOTSUPP;
1327 	}
1328 
1329 	/* protect possible bss_conf changes and avoid concurrency in
1330 	 * ieee80211_bss_info_change_notify()
1331 	 */
1332 	sdata_lock(sdata);
1333 	mutex_lock(&local->mtx);
1334 	tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1335 
1336 	switch (oper) {
1337 	case NL80211_TDLS_ENABLE_LINK:
1338 		if (sdata->vif.csa_active) {
1339 			tdls_dbg(sdata, "TDLS: disallow link during CSA\n");
1340 			ret = -EBUSY;
1341 			break;
1342 		}
1343 
1344 		iee80211_tdls_recalc_chanctx(sdata);
1345 
1346 		mutex_lock(&local->sta_mtx);
1347 		sta = sta_info_get(sdata, peer);
1348 		if (!sta) {
1349 			mutex_unlock(&local->sta_mtx);
1350 			ret = -ENOLINK;
1351 			break;
1352 		}
1353 
1354 		iee80211_tdls_recalc_ht_protection(sdata, sta);
1355 
1356 		set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1357 		mutex_unlock(&local->sta_mtx);
1358 
1359 		WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1360 			     !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1361 		ret = 0;
1362 		break;
1363 	case NL80211_TDLS_DISABLE_LINK:
1364 		/*
1365 		 * The teardown message in ieee80211_tdls_mgmt_teardown() was
1366 		 * created while the queues were stopped, so it might still be
1367 		 * pending. Before flushing the queues we need to be sure the
1368 		 * message is handled by the tasklet handling pending messages,
1369 		 * otherwise we might start destroying the station before
1370 		 * sending the teardown packet.
1371 		 * Note that this only forces the tasklet to flush pendings -
1372 		 * not to stop the tasklet from rescheduling itself.
1373 		 */
1374 		tasklet_kill(&local->tx_pending_tasklet);
1375 		/* flush a potentially queued teardown packet */
1376 		ieee80211_flush_queues(local, sdata, false);
1377 
1378 		ret = sta_info_destroy_addr(sdata, peer);
1379 
1380 		mutex_lock(&local->sta_mtx);
1381 		iee80211_tdls_recalc_ht_protection(sdata, NULL);
1382 		mutex_unlock(&local->sta_mtx);
1383 
1384 		iee80211_tdls_recalc_chanctx(sdata);
1385 		break;
1386 	default:
1387 		ret = -ENOTSUPP;
1388 		break;
1389 	}
1390 
1391 	if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1392 		cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1393 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1394 	}
1395 
1396 	if (ret == 0)
1397 		ieee80211_queue_work(&sdata->local->hw,
1398 				     &sdata->u.mgd.request_smps_work);
1399 
1400 	mutex_unlock(&local->mtx);
1401 	sdata_unlock(sdata);
1402 	return ret;
1403 }
1404 
1405 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1406 				 enum nl80211_tdls_operation oper,
1407 				 u16 reason_code, gfp_t gfp)
1408 {
1409 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1410 
1411 	if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1412 		sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1413 			  oper);
1414 		return;
1415 	}
1416 
1417 	cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1418 }
1419 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1420 
1421 static void
1422 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1423 {
1424 	struct ieee80211_ch_switch_timing *ch_sw;
1425 
1426 	*buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1427 	*buf++ = sizeof(struct ieee80211_ch_switch_timing);
1428 
1429 	ch_sw = (void *)buf;
1430 	ch_sw->switch_time = cpu_to_le16(switch_time);
1431 	ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1432 }
1433 
1434 /* find switch timing IE in SKB ready for Tx */
1435 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1436 {
1437 	struct ieee80211_tdls_data *tf;
1438 	const u8 *ie_start;
1439 
1440 	/*
1441 	 * Get the offset for the new location of the switch timing IE.
1442 	 * The SKB network header will now point to the "payload_type"
1443 	 * element of the TDLS data frame struct.
1444 	 */
1445 	tf = container_of(skb->data + skb_network_offset(skb),
1446 			  struct ieee80211_tdls_data, payload_type);
1447 	ie_start = tf->u.chan_switch_req.variable;
1448 	return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1449 				skb->len - (ie_start - skb->data));
1450 }
1451 
1452 static struct sk_buff *
1453 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1454 			      struct cfg80211_chan_def *chandef,
1455 			      u32 *ch_sw_tm_ie_offset)
1456 {
1457 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1458 	u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1459 		     2 + sizeof(struct ieee80211_ch_switch_timing)];
1460 	int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1461 	u8 *pos = extra_ies;
1462 	struct sk_buff *skb;
1463 
1464 	/*
1465 	 * if chandef points to a wide channel add a Secondary-Channel
1466 	 * Offset information element
1467 	 */
1468 	if (chandef->width == NL80211_CHAN_WIDTH_40) {
1469 		struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1470 		bool ht40plus;
1471 
1472 		*pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1473 		*pos++ = sizeof(*sec_chan_ie);
1474 		sec_chan_ie = (void *)pos;
1475 
1476 		ht40plus = cfg80211_get_chandef_type(chandef) ==
1477 							NL80211_CHAN_HT40PLUS;
1478 		sec_chan_ie->sec_chan_offs = ht40plus ?
1479 					     IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1480 					     IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1481 		pos += sizeof(*sec_chan_ie);
1482 
1483 		extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1484 	}
1485 
1486 	/* just set the values to 0, this is a template */
1487 	iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1488 
1489 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1490 					      WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1491 					      0, 0, !sta->sta.tdls_initiator,
1492 					      extra_ies, extra_ies_len,
1493 					      oper_class, chandef);
1494 	if (!skb)
1495 		return NULL;
1496 
1497 	skb = ieee80211_build_data_template(sdata, skb, 0);
1498 	if (IS_ERR(skb)) {
1499 		tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1500 		return NULL;
1501 	}
1502 
1503 	if (ch_sw_tm_ie_offset) {
1504 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1505 
1506 		if (!tm_ie) {
1507 			tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1508 			dev_kfree_skb_any(skb);
1509 			return NULL;
1510 		}
1511 
1512 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1513 	}
1514 
1515 	tdls_dbg(sdata,
1516 		 "TDLS channel switch request template for %pM ch %d width %d\n",
1517 		 sta->sta.addr, chandef->chan->center_freq, chandef->width);
1518 	return skb;
1519 }
1520 
1521 int
1522 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1523 			      const u8 *addr, u8 oper_class,
1524 			      struct cfg80211_chan_def *chandef)
1525 {
1526 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1527 	struct ieee80211_local *local = sdata->local;
1528 	struct sta_info *sta;
1529 	struct sk_buff *skb = NULL;
1530 	u32 ch_sw_tm_ie;
1531 	int ret;
1532 
1533 	mutex_lock(&local->sta_mtx);
1534 	sta = sta_info_get(sdata, addr);
1535 	if (!sta) {
1536 		tdls_dbg(sdata,
1537 			 "Invalid TDLS peer %pM for channel switch request\n",
1538 			 addr);
1539 		ret = -ENOENT;
1540 		goto out;
1541 	}
1542 
1543 	if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1544 		tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1545 			 addr);
1546 		ret = -ENOTSUPP;
1547 		goto out;
1548 	}
1549 
1550 	skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1551 					    &ch_sw_tm_ie);
1552 	if (!skb) {
1553 		ret = -ENOENT;
1554 		goto out;
1555 	}
1556 
1557 	ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1558 				      chandef, skb, ch_sw_tm_ie);
1559 	if (!ret)
1560 		set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1561 
1562 out:
1563 	mutex_unlock(&local->sta_mtx);
1564 	dev_kfree_skb_any(skb);
1565 	return ret;
1566 }
1567 
1568 void
1569 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1570 				     struct net_device *dev,
1571 				     const u8 *addr)
1572 {
1573 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1574 	struct ieee80211_local *local = sdata->local;
1575 	struct sta_info *sta;
1576 
1577 	mutex_lock(&local->sta_mtx);
1578 	sta = sta_info_get(sdata, addr);
1579 	if (!sta) {
1580 		tdls_dbg(sdata,
1581 			 "Invalid TDLS peer %pM for channel switch cancel\n",
1582 			 addr);
1583 		goto out;
1584 	}
1585 
1586 	if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1587 		tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1588 			 addr);
1589 		goto out;
1590 	}
1591 
1592 	drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1593 	clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1594 
1595 out:
1596 	mutex_unlock(&local->sta_mtx);
1597 }
1598 
1599 static struct sk_buff *
1600 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1601 				   u32 *ch_sw_tm_ie_offset)
1602 {
1603 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1604 	struct sk_buff *skb;
1605 	u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1606 
1607 	/* initial timing are always zero in the template */
1608 	iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1609 
1610 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1611 					WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1612 					0, 0, !sta->sta.tdls_initiator,
1613 					extra_ies, sizeof(extra_ies), 0, NULL);
1614 	if (!skb)
1615 		return NULL;
1616 
1617 	skb = ieee80211_build_data_template(sdata, skb, 0);
1618 	if (IS_ERR(skb)) {
1619 		tdls_dbg(sdata,
1620 			 "Failed building TDLS channel switch resp frame\n");
1621 		return NULL;
1622 	}
1623 
1624 	if (ch_sw_tm_ie_offset) {
1625 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1626 
1627 		if (!tm_ie) {
1628 			tdls_dbg(sdata,
1629 				 "No switch timing IE in TDLS switch resp\n");
1630 			dev_kfree_skb_any(skb);
1631 			return NULL;
1632 		}
1633 
1634 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1635 	}
1636 
1637 	tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1638 		 sta->sta.addr);
1639 	return skb;
1640 }
1641 
1642 static int
1643 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1644 					   struct sk_buff *skb)
1645 {
1646 	struct ieee80211_local *local = sdata->local;
1647 	struct ieee802_11_elems elems;
1648 	struct sta_info *sta;
1649 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1650 	bool local_initiator;
1651 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1652 	int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1653 	struct ieee80211_tdls_ch_sw_params params = {};
1654 	int ret;
1655 
1656 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1657 	params.timestamp = rx_status->device_timestamp;
1658 
1659 	if (skb->len < baselen) {
1660 		tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1661 			 skb->len);
1662 		return -EINVAL;
1663 	}
1664 
1665 	mutex_lock(&local->sta_mtx);
1666 	sta = sta_info_get(sdata, tf->sa);
1667 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1668 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1669 			 tf->sa);
1670 		ret = -EINVAL;
1671 		goto out;
1672 	}
1673 
1674 	params.sta = &sta->sta;
1675 	params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1676 	if (params.status != 0) {
1677 		ret = 0;
1678 		goto call_drv;
1679 	}
1680 
1681 	ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1682 			       skb->len - baselen, false, &elems);
1683 	if (elems.parse_error) {
1684 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1685 		ret = -EINVAL;
1686 		goto out;
1687 	}
1688 
1689 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1690 		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1691 		ret = -EINVAL;
1692 		goto out;
1693 	}
1694 
1695 	/* validate the initiator is set correctly */
1696 	local_initiator =
1697 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1698 	if (local_initiator == sta->sta.tdls_initiator) {
1699 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1700 		ret = -EINVAL;
1701 		goto out;
1702 	}
1703 
1704 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1705 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1706 
1707 	params.tmpl_skb =
1708 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1709 	if (!params.tmpl_skb) {
1710 		ret = -ENOENT;
1711 		goto out;
1712 	}
1713 
1714 call_drv:
1715 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1716 
1717 	tdls_dbg(sdata,
1718 		 "TDLS channel switch response received from %pM status %d\n",
1719 		 tf->sa, params.status);
1720 
1721 out:
1722 	mutex_unlock(&local->sta_mtx);
1723 	dev_kfree_skb_any(params.tmpl_skb);
1724 	return ret;
1725 }
1726 
1727 static int
1728 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1729 					  struct sk_buff *skb)
1730 {
1731 	struct ieee80211_local *local = sdata->local;
1732 	struct ieee802_11_elems elems;
1733 	struct cfg80211_chan_def chandef;
1734 	struct ieee80211_channel *chan;
1735 	enum nl80211_channel_type chan_type;
1736 	int freq;
1737 	u8 target_channel, oper_class;
1738 	bool local_initiator;
1739 	struct sta_info *sta;
1740 	enum ieee80211_band band;
1741 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1742 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1743 	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1744 	struct ieee80211_tdls_ch_sw_params params = {};
1745 	int ret = 0;
1746 
1747 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1748 	params.timestamp = rx_status->device_timestamp;
1749 
1750 	if (skb->len < baselen) {
1751 		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1752 			 skb->len);
1753 		return -EINVAL;
1754 	}
1755 
1756 	target_channel = tf->u.chan_switch_req.target_channel;
1757 	oper_class = tf->u.chan_switch_req.oper_class;
1758 
1759 	/*
1760 	 * We can't easily infer the channel band. The operating class is
1761 	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1762 	 * solution here is to treat channels with number >14 as 5GHz ones,
1763 	 * and specifically check for the (oper_class, channel) combinations
1764 	 * where this doesn't hold. These are thankfully unique according to
1765 	 * IEEE802.11-2012.
1766 	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1767 	 * valid here.
1768 	 */
1769 	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1770 	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1771 	     target_channel < 14)
1772 		band = IEEE80211_BAND_5GHZ;
1773 	else
1774 		band = target_channel < 14 ? IEEE80211_BAND_2GHZ :
1775 					     IEEE80211_BAND_5GHZ;
1776 
1777 	freq = ieee80211_channel_to_frequency(target_channel, band);
1778 	if (freq == 0) {
1779 		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1780 			 target_channel);
1781 		return -EINVAL;
1782 	}
1783 
1784 	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1785 	if (!chan) {
1786 		tdls_dbg(sdata,
1787 			 "Unsupported channel for TDLS chan switch: %d\n",
1788 			 target_channel);
1789 		return -EINVAL;
1790 	}
1791 
1792 	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1793 			       skb->len - baselen, false, &elems);
1794 	if (elems.parse_error) {
1795 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1796 		return -EINVAL;
1797 	}
1798 
1799 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1800 		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1801 		return -EINVAL;
1802 	}
1803 
1804 	if (!elems.sec_chan_offs) {
1805 		chan_type = NL80211_CHAN_HT20;
1806 	} else {
1807 		switch (elems.sec_chan_offs->sec_chan_offs) {
1808 		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1809 			chan_type = NL80211_CHAN_HT40PLUS;
1810 			break;
1811 		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1812 			chan_type = NL80211_CHAN_HT40MINUS;
1813 			break;
1814 		default:
1815 			chan_type = NL80211_CHAN_HT20;
1816 			break;
1817 		}
1818 	}
1819 
1820 	cfg80211_chandef_create(&chandef, chan, chan_type);
1821 
1822 	/* we will be active on the TDLS link */
1823 	if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1824 					   sdata->wdev.iftype)) {
1825 		tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1826 		return -EINVAL;
1827 	}
1828 
1829 	mutex_lock(&local->sta_mtx);
1830 	sta = sta_info_get(sdata, tf->sa);
1831 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1832 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1833 			 tf->sa);
1834 		ret = -EINVAL;
1835 		goto out;
1836 	}
1837 
1838 	params.sta = &sta->sta;
1839 
1840 	/* validate the initiator is set correctly */
1841 	local_initiator =
1842 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1843 	if (local_initiator == sta->sta.tdls_initiator) {
1844 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1845 		ret = -EINVAL;
1846 		goto out;
1847 	}
1848 
1849 	/* peer should have known better */
1850 	if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1851 	    elems.sec_chan_offs->sec_chan_offs) {
1852 		tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1853 		ret = -ENOTSUPP;
1854 		goto out;
1855 	}
1856 
1857 	params.chandef = &chandef;
1858 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1859 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1860 
1861 	params.tmpl_skb =
1862 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1863 						   &params.ch_sw_tm_ie);
1864 	if (!params.tmpl_skb) {
1865 		ret = -ENOENT;
1866 		goto out;
1867 	}
1868 
1869 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1870 
1871 	tdls_dbg(sdata,
1872 		 "TDLS ch switch request received from %pM ch %d width %d\n",
1873 		 tf->sa, params.chandef->chan->center_freq,
1874 		 params.chandef->width);
1875 out:
1876 	mutex_unlock(&local->sta_mtx);
1877 	dev_kfree_skb_any(params.tmpl_skb);
1878 	return ret;
1879 }
1880 
1881 static void
1882 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1883 				      struct sk_buff *skb)
1884 {
1885 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1886 	struct wiphy *wiphy = sdata->local->hw.wiphy;
1887 
1888 	ASSERT_RTNL();
1889 
1890 	/* make sure the driver supports it */
1891 	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1892 		return;
1893 
1894 	/* we want to access the entire packet */
1895 	if (skb_linearize(skb))
1896 		return;
1897 	/*
1898 	 * The packet/size was already validated by mac80211 Rx path, only look
1899 	 * at the action type.
1900 	 */
1901 	switch (tf->action_code) {
1902 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1903 		ieee80211_process_tdls_channel_switch_req(sdata, skb);
1904 		break;
1905 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1906 		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1907 		break;
1908 	default:
1909 		WARN_ON_ONCE(1);
1910 		return;
1911 	}
1912 }
1913 
1914 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1915 {
1916 	struct sta_info *sta;
1917 	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1918 
1919 	rcu_read_lock();
1920 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1921 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1922 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1923 			continue;
1924 
1925 		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1926 					    NL80211_TDLS_TEARDOWN, reason,
1927 					    GFP_ATOMIC);
1928 	}
1929 	rcu_read_unlock();
1930 }
1931 
1932 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1933 {
1934 	struct ieee80211_local *local =
1935 		container_of(wk, struct ieee80211_local, tdls_chsw_work);
1936 	struct ieee80211_sub_if_data *sdata;
1937 	struct sk_buff *skb;
1938 	struct ieee80211_tdls_data *tf;
1939 
1940 	rtnl_lock();
1941 	while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1942 		tf = (struct ieee80211_tdls_data *)skb->data;
1943 		list_for_each_entry(sdata, &local->interfaces, list) {
1944 			if (!ieee80211_sdata_running(sdata) ||
1945 			    sdata->vif.type != NL80211_IFTYPE_STATION ||
1946 			    !ether_addr_equal(tf->da, sdata->vif.addr))
1947 				continue;
1948 
1949 			ieee80211_process_tdls_channel_switch(sdata, skb);
1950 			break;
1951 		}
1952 
1953 		kfree_skb(skb);
1954 	}
1955 	rtnl_unlock();
1956 }
1957