xref: /linux/net/mac80211/tdls.c (revision 2fe05e1139a555ae91f00a812cb9520e7d3022ab)
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 - 2016 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 #include "rate.h"
19 
20 /* give usermode some time for retries in setting up the TDLS session */
21 #define TDLS_PEER_SETUP_TIMEOUT	(15 * HZ)
22 
23 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
24 {
25 	struct ieee80211_sub_if_data *sdata;
26 	struct ieee80211_local *local;
27 
28 	sdata = container_of(wk, struct ieee80211_sub_if_data,
29 			     u.mgd.tdls_peer_del_work.work);
30 	local = sdata->local;
31 
32 	mutex_lock(&local->mtx);
33 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
34 		tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
35 		sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
36 		eth_zero_addr(sdata->u.mgd.tdls_peer);
37 	}
38 	mutex_unlock(&local->mtx);
39 }
40 
41 static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
42 					 struct sk_buff *skb)
43 {
44 	struct ieee80211_local *local = sdata->local;
45 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
46 	bool chan_switch = local->hw.wiphy->features &
47 			   NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
48 	bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW) &&
49 			  !ifmgd->tdls_wider_bw_prohibited;
50 	struct ieee80211_supported_band *sband = ieee80211_get_sband(sdata);
51 	bool vht = sband && sband->vht_cap.vht_supported;
52 	u8 *pos = skb_put(skb, 10);
53 
54 	*pos++ = WLAN_EID_EXT_CAPABILITY;
55 	*pos++ = 8; /* len */
56 	*pos++ = 0x0;
57 	*pos++ = 0x0;
58 	*pos++ = 0x0;
59 	*pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
60 	*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
61 	*pos++ = 0;
62 	*pos++ = 0;
63 	*pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
64 }
65 
66 static u8
67 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
68 			   struct sk_buff *skb, u16 start, u16 end,
69 			   u16 spacing)
70 {
71 	u8 subband_cnt = 0, ch_cnt = 0;
72 	struct ieee80211_channel *ch;
73 	struct cfg80211_chan_def chandef;
74 	int i, subband_start;
75 	struct wiphy *wiphy = sdata->local->hw.wiphy;
76 
77 	for (i = start; i <= end; i += spacing) {
78 		if (!ch_cnt)
79 			subband_start = i;
80 
81 		ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
82 		if (ch) {
83 			/* we will be active on the channel */
84 			cfg80211_chandef_create(&chandef, ch,
85 						NL80211_CHAN_NO_HT);
86 			if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
87 							  sdata->wdev.iftype)) {
88 				ch_cnt++;
89 				/*
90 				 * check if the next channel is also part of
91 				 * this allowed range
92 				 */
93 				continue;
94 			}
95 		}
96 
97 		/*
98 		 * we've reached the end of a range, with allowed channels
99 		 * found
100 		 */
101 		if (ch_cnt) {
102 			u8 *pos = skb_put(skb, 2);
103 			*pos++ = ieee80211_frequency_to_channel(subband_start);
104 			*pos++ = ch_cnt;
105 
106 			subband_cnt++;
107 			ch_cnt = 0;
108 		}
109 	}
110 
111 	/* all channels in the requested range are allowed - add them here */
112 	if (ch_cnt) {
113 		u8 *pos = skb_put(skb, 2);
114 		*pos++ = ieee80211_frequency_to_channel(subband_start);
115 		*pos++ = ch_cnt;
116 
117 		subband_cnt++;
118 	}
119 
120 	return subband_cnt;
121 }
122 
123 static void
124 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
125 				 struct sk_buff *skb)
126 {
127 	/*
128 	 * Add possible channels for TDLS. These are channels that are allowed
129 	 * to be active.
130 	 */
131 	u8 subband_cnt;
132 	u8 *pos = skb_put(skb, 2);
133 
134 	*pos++ = WLAN_EID_SUPPORTED_CHANNELS;
135 
136 	/*
137 	 * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
138 	 * this doesn't happen in real world scenarios.
139 	 */
140 
141 	/* 2GHz, with 5MHz spacing */
142 	subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
143 
144 	/* 5GHz, with 20MHz spacing */
145 	subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
146 
147 	/* length */
148 	*pos = 2 * subband_cnt;
149 }
150 
151 static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
152 					    struct sk_buff *skb)
153 {
154 	u8 *pos;
155 	u8 op_class;
156 
157 	if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
158 						  &op_class))
159 		return;
160 
161 	pos = skb_put(skb, 4);
162 	*pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
163 	*pos++ = 2; /* len */
164 
165 	*pos++ = op_class;
166 	*pos++ = op_class; /* give current operating class as alternate too */
167 }
168 
169 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
170 {
171 	u8 *pos = skb_put(skb, 3);
172 
173 	*pos++ = WLAN_EID_BSS_COEX_2040;
174 	*pos++ = 1; /* len */
175 
176 	*pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
177 }
178 
179 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
180 					u16 status_code)
181 {
182 	struct ieee80211_supported_band *sband;
183 
184 	/* The capability will be 0 when sending a failure code */
185 	if (status_code != 0)
186 		return 0;
187 
188 	sband = ieee80211_get_sband(sdata);
189 	if (sband && sband->band == NL80211_BAND_2GHZ) {
190 		return WLAN_CAPABILITY_SHORT_SLOT_TIME |
191 		       WLAN_CAPABILITY_SHORT_PREAMBLE;
192 	}
193 
194 	return 0;
195 }
196 
197 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
198 				       struct sk_buff *skb, const u8 *peer,
199 				       bool initiator)
200 {
201 	struct ieee80211_tdls_lnkie *lnkid;
202 	const u8 *init_addr, *rsp_addr;
203 
204 	if (initiator) {
205 		init_addr = sdata->vif.addr;
206 		rsp_addr = peer;
207 	} else {
208 		init_addr = peer;
209 		rsp_addr = sdata->vif.addr;
210 	}
211 
212 	lnkid = skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
213 
214 	lnkid->ie_type = WLAN_EID_LINK_ID;
215 	lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
216 
217 	memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
218 	memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
219 	memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
220 }
221 
222 static void
223 ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
224 {
225 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
226 	u8 *pos = skb_put(skb, 4);
227 
228 	*pos++ = WLAN_EID_AID;
229 	*pos++ = 2; /* len */
230 	put_unaligned_le16(ifmgd->aid, pos);
231 }
232 
233 /* translate numbering in the WMM parameter IE to the mac80211 notation */
234 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
235 {
236 	switch (ac) {
237 	default:
238 		WARN_ON_ONCE(1);
239 	case 0:
240 		return IEEE80211_AC_BE;
241 	case 1:
242 		return IEEE80211_AC_BK;
243 	case 2:
244 		return IEEE80211_AC_VI;
245 	case 3:
246 		return IEEE80211_AC_VO;
247 	}
248 }
249 
250 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
251 {
252 	u8 ret;
253 
254 	ret = aifsn & 0x0f;
255 	if (acm)
256 		ret |= 0x10;
257 	ret |= (aci << 5) & 0x60;
258 	return ret;
259 }
260 
261 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
262 {
263 	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
264 	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
265 }
266 
267 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
268 					    struct sk_buff *skb)
269 {
270 	struct ieee80211_wmm_param_ie *wmm;
271 	struct ieee80211_tx_queue_params *txq;
272 	int i;
273 
274 	wmm = skb_put_zero(skb, sizeof(*wmm));
275 
276 	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
277 	wmm->len = sizeof(*wmm) - 2;
278 
279 	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
280 	wmm->oui[1] = 0x50;
281 	wmm->oui[2] = 0xf2;
282 	wmm->oui_type = 2; /* WME */
283 	wmm->oui_subtype = 1; /* WME param */
284 	wmm->version = 1; /* WME ver */
285 	wmm->qos_info = 0; /* U-APSD not in use */
286 
287 	/*
288 	 * Use the EDCA parameters defined for the BSS, or default if the AP
289 	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
290 	 */
291 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
292 		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
293 		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
294 							       txq->acm, i);
295 		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
296 		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
297 	}
298 }
299 
300 static void
301 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
302 				   struct sta_info *sta)
303 {
304 	/* IEEE802.11ac-2013 Table E-4 */
305 	u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
306 	struct cfg80211_chan_def uc = sta->tdls_chandef;
307 	enum nl80211_chan_width max_width = ieee80211_sta_cap_chan_bw(sta);
308 	int i;
309 
310 	/* only support upgrading non-narrow channels up to 80Mhz */
311 	if (max_width == NL80211_CHAN_WIDTH_5 ||
312 	    max_width == NL80211_CHAN_WIDTH_10)
313 		return;
314 
315 	if (max_width > NL80211_CHAN_WIDTH_80)
316 		max_width = NL80211_CHAN_WIDTH_80;
317 
318 	if (uc.width >= max_width)
319 		return;
320 	/*
321 	 * Channel usage constrains in the IEEE802.11ac-2013 specification only
322 	 * allow expanding a 20MHz channel to 80MHz in a single way. In
323 	 * addition, there are no 40MHz allowed channels that are not part of
324 	 * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
325 	 */
326 	for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
327 		if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
328 			uc.center_freq1 = centers_80mhz[i];
329 			uc.center_freq2 = 0;
330 			uc.width = NL80211_CHAN_WIDTH_80;
331 			break;
332 		}
333 
334 	if (!uc.center_freq1)
335 		return;
336 
337 	/* proceed to downgrade the chandef until usable or the same as AP BW */
338 	while (uc.width > max_width ||
339 	       (uc.width > sta->tdls_chandef.width &&
340 		!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &uc,
341 					       sdata->wdev.iftype)))
342 		ieee80211_chandef_downgrade(&uc);
343 
344 	if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
345 		tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
346 			 sta->tdls_chandef.width, uc.width);
347 
348 		/*
349 		 * the station is not yet authorized when BW upgrade is done,
350 		 * locking is not required
351 		 */
352 		sta->tdls_chandef = uc;
353 	}
354 }
355 
356 static void
357 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
358 				   struct sk_buff *skb, const u8 *peer,
359 				   u8 action_code, bool initiator,
360 				   const u8 *extra_ies, size_t extra_ies_len)
361 {
362 	struct ieee80211_supported_band *sband;
363 	struct ieee80211_local *local = sdata->local;
364 	struct ieee80211_sta_ht_cap ht_cap;
365 	struct ieee80211_sta_vht_cap vht_cap;
366 	struct sta_info *sta = NULL;
367 	size_t offset = 0, noffset;
368 	u8 *pos;
369 
370 	sband = ieee80211_get_sband(sdata);
371 	if (!sband)
372 		return;
373 
374 	ieee80211_add_srates_ie(sdata, skb, false, sband->band);
375 	ieee80211_add_ext_srates_ie(sdata, skb, false, sband->band);
376 	ieee80211_tdls_add_supp_channels(sdata, skb);
377 
378 	/* add any custom IEs that go before Extended Capabilities */
379 	if (extra_ies_len) {
380 		static const u8 before_ext_cap[] = {
381 			WLAN_EID_SUPP_RATES,
382 			WLAN_EID_COUNTRY,
383 			WLAN_EID_EXT_SUPP_RATES,
384 			WLAN_EID_SUPPORTED_CHANNELS,
385 			WLAN_EID_RSN,
386 		};
387 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
388 					     before_ext_cap,
389 					     ARRAY_SIZE(before_ext_cap),
390 					     offset);
391 		skb_put_data(skb, extra_ies + offset, noffset - offset);
392 		offset = noffset;
393 	}
394 
395 	ieee80211_tdls_add_ext_capab(sdata, skb);
396 
397 	/* add the QoS element if we support it */
398 	if (local->hw.queues >= IEEE80211_NUM_ACS &&
399 	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
400 		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
401 
402 	/* add any custom IEs that go before HT capabilities */
403 	if (extra_ies_len) {
404 		static const u8 before_ht_cap[] = {
405 			WLAN_EID_SUPP_RATES,
406 			WLAN_EID_COUNTRY,
407 			WLAN_EID_EXT_SUPP_RATES,
408 			WLAN_EID_SUPPORTED_CHANNELS,
409 			WLAN_EID_RSN,
410 			WLAN_EID_EXT_CAPABILITY,
411 			WLAN_EID_QOS_CAPA,
412 			WLAN_EID_FAST_BSS_TRANSITION,
413 			WLAN_EID_TIMEOUT_INTERVAL,
414 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
415 		};
416 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
417 					     before_ht_cap,
418 					     ARRAY_SIZE(before_ht_cap),
419 					     offset);
420 		skb_put_data(skb, extra_ies + offset, noffset - offset);
421 		offset = noffset;
422 	}
423 
424 	mutex_lock(&local->sta_mtx);
425 
426 	/* we should have the peer STA if we're already responding */
427 	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
428 		sta = sta_info_get(sdata, peer);
429 		if (WARN_ON_ONCE(!sta)) {
430 			mutex_unlock(&local->sta_mtx);
431 			return;
432 		}
433 
434 		sta->tdls_chandef = sdata->vif.bss_conf.chandef;
435 	}
436 
437 	ieee80211_tdls_add_oper_classes(sdata, skb);
438 
439 	/*
440 	 * with TDLS we can switch channels, and HT-caps are not necessarily
441 	 * the same on all bands. The specification limits the setup to a
442 	 * single HT-cap, so use the current band for now.
443 	 */
444 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
445 
446 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
447 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
448 	    ht_cap.ht_supported) {
449 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
450 
451 		/* disable SMPS in TDLS initiator */
452 		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
453 				<< IEEE80211_HT_CAP_SM_PS_SHIFT;
454 
455 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
456 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
457 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
458 		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
459 		/* the peer caps are already intersected with our own */
460 		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
461 
462 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
463 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
464 	}
465 
466 	if (ht_cap.ht_supported &&
467 	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
468 		ieee80211_tdls_add_bss_coex_ie(skb);
469 
470 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
471 
472 	/* add any custom IEs that go before VHT capabilities */
473 	if (extra_ies_len) {
474 		static const u8 before_vht_cap[] = {
475 			WLAN_EID_SUPP_RATES,
476 			WLAN_EID_COUNTRY,
477 			WLAN_EID_EXT_SUPP_RATES,
478 			WLAN_EID_SUPPORTED_CHANNELS,
479 			WLAN_EID_RSN,
480 			WLAN_EID_EXT_CAPABILITY,
481 			WLAN_EID_QOS_CAPA,
482 			WLAN_EID_FAST_BSS_TRANSITION,
483 			WLAN_EID_TIMEOUT_INTERVAL,
484 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
485 			WLAN_EID_MULTI_BAND,
486 		};
487 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
488 					     before_vht_cap,
489 					     ARRAY_SIZE(before_vht_cap),
490 					     offset);
491 		skb_put_data(skb, extra_ies + offset, noffset - offset);
492 		offset = noffset;
493 	}
494 
495 	/* build the VHT-cap similarly to the HT-cap */
496 	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
497 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
498 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
499 	    vht_cap.vht_supported) {
500 		ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
501 
502 		/* the AID is present only when VHT is implemented */
503 		if (action_code == WLAN_TDLS_SETUP_REQUEST)
504 			ieee80211_tdls_add_aid(sdata, skb);
505 
506 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
507 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
508 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
509 		   vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
510 		/* the peer caps are already intersected with our own */
511 		memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
512 
513 		/* the AID is present only when VHT is implemented */
514 		ieee80211_tdls_add_aid(sdata, skb);
515 
516 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
517 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
518 
519 		/*
520 		 * if both peers support WIDER_BW, we can expand the chandef to
521 		 * a wider compatible one, up to 80MHz
522 		 */
523 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
524 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
525 	}
526 
527 	mutex_unlock(&local->sta_mtx);
528 
529 	/* add any remaining IEs */
530 	if (extra_ies_len) {
531 		noffset = extra_ies_len;
532 		skb_put_data(skb, extra_ies + offset, noffset - offset);
533 	}
534 
535 }
536 
537 static void
538 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
539 				 struct sk_buff *skb, const u8 *peer,
540 				 bool initiator, const u8 *extra_ies,
541 				 size_t extra_ies_len)
542 {
543 	struct ieee80211_local *local = sdata->local;
544 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
545 	size_t offset = 0, noffset;
546 	struct sta_info *sta, *ap_sta;
547 	struct ieee80211_supported_band *sband;
548 	u8 *pos;
549 
550 	sband = ieee80211_get_sband(sdata);
551 	if (!sband)
552 		return;
553 
554 	mutex_lock(&local->sta_mtx);
555 
556 	sta = sta_info_get(sdata, peer);
557 	ap_sta = sta_info_get(sdata, ifmgd->bssid);
558 	if (WARN_ON_ONCE(!sta || !ap_sta)) {
559 		mutex_unlock(&local->sta_mtx);
560 		return;
561 	}
562 
563 	sta->tdls_chandef = sdata->vif.bss_conf.chandef;
564 
565 	/* add any custom IEs that go before the QoS IE */
566 	if (extra_ies_len) {
567 		static const u8 before_qos[] = {
568 			WLAN_EID_RSN,
569 		};
570 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
571 					     before_qos,
572 					     ARRAY_SIZE(before_qos),
573 					     offset);
574 		skb_put_data(skb, extra_ies + offset, noffset - offset);
575 		offset = noffset;
576 	}
577 
578 	/* add the QoS param IE if both the peer and we support it */
579 	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
580 		ieee80211_tdls_add_wmm_param_ie(sdata, skb);
581 
582 	/* add any custom IEs that go before HT operation */
583 	if (extra_ies_len) {
584 		static const u8 before_ht_op[] = {
585 			WLAN_EID_RSN,
586 			WLAN_EID_QOS_CAPA,
587 			WLAN_EID_FAST_BSS_TRANSITION,
588 			WLAN_EID_TIMEOUT_INTERVAL,
589 		};
590 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
591 					     before_ht_op,
592 					     ARRAY_SIZE(before_ht_op),
593 					     offset);
594 		skb_put_data(skb, extra_ies + offset, noffset - offset);
595 		offset = noffset;
596 	}
597 
598 	/*
599 	 * if HT support is only added in TDLS, we need an HT-operation IE.
600 	 * add the IE as required by IEEE802.11-2012 9.23.3.2.
601 	 */
602 	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
603 		u16 prot = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
604 			   IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
605 			   IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
606 
607 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
608 		ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
609 					   &sdata->vif.bss_conf.chandef, prot,
610 					   true);
611 	}
612 
613 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
614 
615 	/* only include VHT-operation if not on the 2.4GHz band */
616 	if (sband->band != NL80211_BAND_2GHZ &&
617 	    sta->sta.vht_cap.vht_supported) {
618 		/*
619 		 * if both peers support WIDER_BW, we can expand the chandef to
620 		 * a wider compatible one, up to 80MHz
621 		 */
622 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
623 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
624 
625 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
626 		ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
627 					    &sta->tdls_chandef);
628 	}
629 
630 	mutex_unlock(&local->sta_mtx);
631 
632 	/* add any remaining IEs */
633 	if (extra_ies_len) {
634 		noffset = extra_ies_len;
635 		skb_put_data(skb, extra_ies + offset, noffset - offset);
636 	}
637 }
638 
639 static void
640 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
641 				       struct sk_buff *skb, const u8 *peer,
642 				       bool initiator, const u8 *extra_ies,
643 				       size_t extra_ies_len, u8 oper_class,
644 				       struct cfg80211_chan_def *chandef)
645 {
646 	struct ieee80211_tdls_data *tf;
647 	size_t offset = 0, noffset;
648 
649 	if (WARN_ON_ONCE(!chandef))
650 		return;
651 
652 	tf = (void *)skb->data;
653 	tf->u.chan_switch_req.target_channel =
654 		ieee80211_frequency_to_channel(chandef->chan->center_freq);
655 	tf->u.chan_switch_req.oper_class = oper_class;
656 
657 	if (extra_ies_len) {
658 		static const u8 before_lnkie[] = {
659 			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
660 		};
661 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
662 					     before_lnkie,
663 					     ARRAY_SIZE(before_lnkie),
664 					     offset);
665 		skb_put_data(skb, extra_ies + offset, noffset - offset);
666 		offset = noffset;
667 	}
668 
669 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
670 
671 	/* add any remaining IEs */
672 	if (extra_ies_len) {
673 		noffset = extra_ies_len;
674 		skb_put_data(skb, extra_ies + offset, noffset - offset);
675 	}
676 }
677 
678 static void
679 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
680 					struct sk_buff *skb, const u8 *peer,
681 					u16 status_code, bool initiator,
682 					const u8 *extra_ies,
683 					size_t extra_ies_len)
684 {
685 	if (status_code == 0)
686 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
687 
688 	if (extra_ies_len)
689 		skb_put_data(skb, extra_ies, extra_ies_len);
690 }
691 
692 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
693 				   struct sk_buff *skb, const u8 *peer,
694 				   u8 action_code, u16 status_code,
695 				   bool initiator, const u8 *extra_ies,
696 				   size_t extra_ies_len, u8 oper_class,
697 				   struct cfg80211_chan_def *chandef)
698 {
699 	switch (action_code) {
700 	case WLAN_TDLS_SETUP_REQUEST:
701 	case WLAN_TDLS_SETUP_RESPONSE:
702 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
703 		if (status_code == 0)
704 			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
705 							   action_code,
706 							   initiator,
707 							   extra_ies,
708 							   extra_ies_len);
709 		break;
710 	case WLAN_TDLS_SETUP_CONFIRM:
711 		if (status_code == 0)
712 			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
713 							 initiator, extra_ies,
714 							 extra_ies_len);
715 		break;
716 	case WLAN_TDLS_TEARDOWN:
717 	case WLAN_TDLS_DISCOVERY_REQUEST:
718 		if (extra_ies_len)
719 			skb_put_data(skb, extra_ies, extra_ies_len);
720 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
721 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
722 		break;
723 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
724 		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
725 						       initiator, extra_ies,
726 						       extra_ies_len,
727 						       oper_class, chandef);
728 		break;
729 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
730 		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
731 							status_code,
732 							initiator, extra_ies,
733 							extra_ies_len);
734 		break;
735 	}
736 
737 }
738 
739 static int
740 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
741 			       const u8 *peer, u8 action_code, u8 dialog_token,
742 			       u16 status_code, struct sk_buff *skb)
743 {
744 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
745 	struct ieee80211_tdls_data *tf;
746 
747 	tf = skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
748 
749 	memcpy(tf->da, peer, ETH_ALEN);
750 	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
751 	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
752 	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
753 
754 	/* network header is after the ethernet header */
755 	skb_set_network_header(skb, ETH_HLEN);
756 
757 	switch (action_code) {
758 	case WLAN_TDLS_SETUP_REQUEST:
759 		tf->category = WLAN_CATEGORY_TDLS;
760 		tf->action_code = WLAN_TDLS_SETUP_REQUEST;
761 
762 		skb_put(skb, sizeof(tf->u.setup_req));
763 		tf->u.setup_req.dialog_token = dialog_token;
764 		tf->u.setup_req.capability =
765 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
766 								 status_code));
767 		break;
768 	case WLAN_TDLS_SETUP_RESPONSE:
769 		tf->category = WLAN_CATEGORY_TDLS;
770 		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
771 
772 		skb_put(skb, sizeof(tf->u.setup_resp));
773 		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
774 		tf->u.setup_resp.dialog_token = dialog_token;
775 		tf->u.setup_resp.capability =
776 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
777 								 status_code));
778 		break;
779 	case WLAN_TDLS_SETUP_CONFIRM:
780 		tf->category = WLAN_CATEGORY_TDLS;
781 		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
782 
783 		skb_put(skb, sizeof(tf->u.setup_cfm));
784 		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
785 		tf->u.setup_cfm.dialog_token = dialog_token;
786 		break;
787 	case WLAN_TDLS_TEARDOWN:
788 		tf->category = WLAN_CATEGORY_TDLS;
789 		tf->action_code = WLAN_TDLS_TEARDOWN;
790 
791 		skb_put(skb, sizeof(tf->u.teardown));
792 		tf->u.teardown.reason_code = cpu_to_le16(status_code);
793 		break;
794 	case WLAN_TDLS_DISCOVERY_REQUEST:
795 		tf->category = WLAN_CATEGORY_TDLS;
796 		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
797 
798 		skb_put(skb, sizeof(tf->u.discover_req));
799 		tf->u.discover_req.dialog_token = dialog_token;
800 		break;
801 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
802 		tf->category = WLAN_CATEGORY_TDLS;
803 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
804 
805 		skb_put(skb, sizeof(tf->u.chan_switch_req));
806 		break;
807 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
808 		tf->category = WLAN_CATEGORY_TDLS;
809 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
810 
811 		skb_put(skb, sizeof(tf->u.chan_switch_resp));
812 		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
813 		break;
814 	default:
815 		return -EINVAL;
816 	}
817 
818 	return 0;
819 }
820 
821 static int
822 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
823 			   const u8 *peer, u8 action_code, u8 dialog_token,
824 			   u16 status_code, struct sk_buff *skb)
825 {
826 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
827 	struct ieee80211_mgmt *mgmt;
828 
829 	mgmt = skb_put_zero(skb, 24);
830 	memcpy(mgmt->da, peer, ETH_ALEN);
831 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
832 	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
833 
834 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
835 					  IEEE80211_STYPE_ACTION);
836 
837 	switch (action_code) {
838 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
839 		skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
840 		mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
841 		mgmt->u.action.u.tdls_discover_resp.action_code =
842 			WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
843 		mgmt->u.action.u.tdls_discover_resp.dialog_token =
844 			dialog_token;
845 		mgmt->u.action.u.tdls_discover_resp.capability =
846 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
847 								 status_code));
848 		break;
849 	default:
850 		return -EINVAL;
851 	}
852 
853 	return 0;
854 }
855 
856 static struct sk_buff *
857 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
858 				      const u8 *peer, u8 action_code,
859 				      u8 dialog_token, u16 status_code,
860 				      bool initiator, const u8 *extra_ies,
861 				      size_t extra_ies_len, u8 oper_class,
862 				      struct cfg80211_chan_def *chandef)
863 {
864 	struct ieee80211_local *local = sdata->local;
865 	struct sk_buff *skb;
866 	int ret;
867 
868 	skb = netdev_alloc_skb(sdata->dev,
869 			       local->hw.extra_tx_headroom +
870 			       max(sizeof(struct ieee80211_mgmt),
871 				   sizeof(struct ieee80211_tdls_data)) +
872 			       50 + /* supported rates */
873 			       10 + /* ext capab */
874 			       26 + /* max(WMM-info, WMM-param) */
875 			       2 + max(sizeof(struct ieee80211_ht_cap),
876 				       sizeof(struct ieee80211_ht_operation)) +
877 			       2 + max(sizeof(struct ieee80211_vht_cap),
878 				       sizeof(struct ieee80211_vht_operation)) +
879 			       50 + /* supported channels */
880 			       3 + /* 40/20 BSS coex */
881 			       4 + /* AID */
882 			       4 + /* oper classes */
883 			       extra_ies_len +
884 			       sizeof(struct ieee80211_tdls_lnkie));
885 	if (!skb)
886 		return NULL;
887 
888 	skb_reserve(skb, local->hw.extra_tx_headroom);
889 
890 	switch (action_code) {
891 	case WLAN_TDLS_SETUP_REQUEST:
892 	case WLAN_TDLS_SETUP_RESPONSE:
893 	case WLAN_TDLS_SETUP_CONFIRM:
894 	case WLAN_TDLS_TEARDOWN:
895 	case WLAN_TDLS_DISCOVERY_REQUEST:
896 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
897 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
898 		ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
899 						     sdata->dev, peer,
900 						     action_code, dialog_token,
901 						     status_code, skb);
902 		break;
903 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
904 		ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
905 						 peer, action_code,
906 						 dialog_token, status_code,
907 						 skb);
908 		break;
909 	default:
910 		ret = -ENOTSUPP;
911 		break;
912 	}
913 
914 	if (ret < 0)
915 		goto fail;
916 
917 	ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
918 			       initiator, extra_ies, extra_ies_len, oper_class,
919 			       chandef);
920 	return skb;
921 
922 fail:
923 	dev_kfree_skb(skb);
924 	return NULL;
925 }
926 
927 static int
928 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
929 				const u8 *peer, u8 action_code, u8 dialog_token,
930 				u16 status_code, u32 peer_capability,
931 				bool initiator, const u8 *extra_ies,
932 				size_t extra_ies_len, u8 oper_class,
933 				struct cfg80211_chan_def *chandef)
934 {
935 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
936 	struct sk_buff *skb = NULL;
937 	struct sta_info *sta;
938 	u32 flags = 0;
939 	int ret = 0;
940 
941 	rcu_read_lock();
942 	sta = sta_info_get(sdata, peer);
943 
944 	/* infer the initiator if we can, to support old userspace */
945 	switch (action_code) {
946 	case WLAN_TDLS_SETUP_REQUEST:
947 		if (sta) {
948 			set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
949 			sta->sta.tdls_initiator = false;
950 		}
951 		/* fall-through */
952 	case WLAN_TDLS_SETUP_CONFIRM:
953 	case WLAN_TDLS_DISCOVERY_REQUEST:
954 		initiator = true;
955 		break;
956 	case WLAN_TDLS_SETUP_RESPONSE:
957 		/*
958 		 * In some testing scenarios, we send a request and response.
959 		 * Make the last packet sent take effect for the initiator
960 		 * value.
961 		 */
962 		if (sta) {
963 			clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
964 			sta->sta.tdls_initiator = true;
965 		}
966 		/* fall-through */
967 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
968 		initiator = false;
969 		break;
970 	case WLAN_TDLS_TEARDOWN:
971 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
972 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
973 		/* any value is ok */
974 		break;
975 	default:
976 		ret = -ENOTSUPP;
977 		break;
978 	}
979 
980 	if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
981 		initiator = true;
982 
983 	rcu_read_unlock();
984 	if (ret < 0)
985 		goto fail;
986 
987 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
988 						    dialog_token, status_code,
989 						    initiator, extra_ies,
990 						    extra_ies_len, oper_class,
991 						    chandef);
992 	if (!skb) {
993 		ret = -EINVAL;
994 		goto fail;
995 	}
996 
997 	if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
998 		ieee80211_tx_skb(sdata, skb);
999 		return 0;
1000 	}
1001 
1002 	/*
1003 	 * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
1004 	 * we should default to AC_VI.
1005 	 */
1006 	switch (action_code) {
1007 	case WLAN_TDLS_SETUP_REQUEST:
1008 	case WLAN_TDLS_SETUP_RESPONSE:
1009 		skb_set_queue_mapping(skb, IEEE80211_AC_BK);
1010 		skb->priority = 2;
1011 		break;
1012 	default:
1013 		skb_set_queue_mapping(skb, IEEE80211_AC_VI);
1014 		skb->priority = 5;
1015 		break;
1016 	}
1017 
1018 	/*
1019 	 * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
1020 	 * Later, if no ACK is returned from peer, we will re-send the teardown
1021 	 * packet through the AP.
1022 	 */
1023 	if ((action_code == WLAN_TDLS_TEARDOWN) &&
1024 	    ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
1025 		bool try_resend; /* Should we keep skb for possible resend */
1026 
1027 		/* If not sending directly to peer - no point in keeping skb */
1028 		rcu_read_lock();
1029 		sta = sta_info_get(sdata, peer);
1030 		try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1031 		rcu_read_unlock();
1032 
1033 		spin_lock_bh(&sdata->u.mgd.teardown_lock);
1034 		if (try_resend && !sdata->u.mgd.teardown_skb) {
1035 			/* Mark it as requiring TX status callback  */
1036 			flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
1037 				 IEEE80211_TX_INTFL_MLME_CONN_TX;
1038 
1039 			/*
1040 			 * skb is copied since mac80211 will later set
1041 			 * properties that might not be the same as the AP,
1042 			 * such as encryption, QoS, addresses, etc.
1043 			 *
1044 			 * No problem if skb_copy() fails, so no need to check.
1045 			 */
1046 			sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
1047 			sdata->u.mgd.orig_teardown_skb = skb;
1048 		}
1049 		spin_unlock_bh(&sdata->u.mgd.teardown_lock);
1050 	}
1051 
1052 	/* disable bottom halves when entering the Tx path */
1053 	local_bh_disable();
1054 	__ieee80211_subif_start_xmit(skb, dev, flags);
1055 	local_bh_enable();
1056 
1057 	return ret;
1058 
1059 fail:
1060 	dev_kfree_skb(skb);
1061 	return ret;
1062 }
1063 
1064 static int
1065 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
1066 			  const u8 *peer, u8 action_code, u8 dialog_token,
1067 			  u16 status_code, u32 peer_capability, bool initiator,
1068 			  const u8 *extra_ies, size_t extra_ies_len)
1069 {
1070 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1071 	struct ieee80211_local *local = sdata->local;
1072 	enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
1073 	int ret;
1074 
1075 	/* don't support setup with forced SMPS mode that's not off */
1076 	if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
1077 	    smps_mode != IEEE80211_SMPS_OFF) {
1078 		tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
1079 			 smps_mode);
1080 		return -ENOTSUPP;
1081 	}
1082 
1083 	mutex_lock(&local->mtx);
1084 
1085 	/* we don't support concurrent TDLS peer setups */
1086 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
1087 	    !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1088 		ret = -EBUSY;
1089 		goto out_unlock;
1090 	}
1091 
1092 	/*
1093 	 * make sure we have a STA representing the peer so we drop or buffer
1094 	 * non-TDLS-setup frames to the peer. We can't send other packets
1095 	 * during setup through the AP path.
1096 	 * Allow error packets to be sent - sometimes we don't even add a STA
1097 	 * before failing the setup.
1098 	 */
1099 	if (status_code == 0) {
1100 		rcu_read_lock();
1101 		if (!sta_info_get(sdata, peer)) {
1102 			rcu_read_unlock();
1103 			ret = -ENOLINK;
1104 			goto out_unlock;
1105 		}
1106 		rcu_read_unlock();
1107 	}
1108 
1109 	ieee80211_flush_queues(local, sdata, false);
1110 	memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
1111 	mutex_unlock(&local->mtx);
1112 
1113 	/* we cannot take the mutex while preparing the setup packet */
1114 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1115 					      dialog_token, status_code,
1116 					      peer_capability, initiator,
1117 					      extra_ies, extra_ies_len, 0,
1118 					      NULL);
1119 	if (ret < 0) {
1120 		mutex_lock(&local->mtx);
1121 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1122 		mutex_unlock(&local->mtx);
1123 		return ret;
1124 	}
1125 
1126 	ieee80211_queue_delayed_work(&sdata->local->hw,
1127 				     &sdata->u.mgd.tdls_peer_del_work,
1128 				     TDLS_PEER_SETUP_TIMEOUT);
1129 	return 0;
1130 
1131 out_unlock:
1132 	mutex_unlock(&local->mtx);
1133 	return ret;
1134 }
1135 
1136 static int
1137 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
1138 			     const u8 *peer, u8 action_code, u8 dialog_token,
1139 			     u16 status_code, u32 peer_capability,
1140 			     bool initiator, const u8 *extra_ies,
1141 			     size_t extra_ies_len)
1142 {
1143 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1144 	struct ieee80211_local *local = sdata->local;
1145 	struct sta_info *sta;
1146 	int ret;
1147 
1148 	/*
1149 	 * No packets can be transmitted to the peer via the AP during setup -
1150 	 * the STA is set as a TDLS peer, but is not authorized.
1151 	 * During teardown, we prevent direct transmissions by stopping the
1152 	 * queues and flushing all direct packets.
1153 	 */
1154 	ieee80211_stop_vif_queues(local, sdata,
1155 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1156 	ieee80211_flush_queues(local, sdata, false);
1157 
1158 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1159 					      dialog_token, status_code,
1160 					      peer_capability, initiator,
1161 					      extra_ies, extra_ies_len, 0,
1162 					      NULL);
1163 	if (ret < 0)
1164 		sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
1165 			  ret);
1166 
1167 	/*
1168 	 * Remove the STA AUTH flag to force further traffic through the AP. If
1169 	 * the STA was unreachable, it was already removed.
1170 	 */
1171 	rcu_read_lock();
1172 	sta = sta_info_get(sdata, peer);
1173 	if (sta)
1174 		clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1175 	rcu_read_unlock();
1176 
1177 	ieee80211_wake_vif_queues(local, sdata,
1178 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1179 
1180 	return 0;
1181 }
1182 
1183 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
1184 			const u8 *peer, u8 action_code, u8 dialog_token,
1185 			u16 status_code, u32 peer_capability,
1186 			bool initiator, const u8 *extra_ies,
1187 			size_t extra_ies_len)
1188 {
1189 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1190 	int ret;
1191 
1192 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1193 		return -ENOTSUPP;
1194 
1195 	/* make sure we are in managed mode, and associated */
1196 	if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1197 	    !sdata->u.mgd.associated)
1198 		return -EINVAL;
1199 
1200 	switch (action_code) {
1201 	case WLAN_TDLS_SETUP_REQUEST:
1202 	case WLAN_TDLS_SETUP_RESPONSE:
1203 		ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1204 						dialog_token, status_code,
1205 						peer_capability, initiator,
1206 						extra_ies, extra_ies_len);
1207 		break;
1208 	case WLAN_TDLS_TEARDOWN:
1209 		ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1210 						   action_code, dialog_token,
1211 						   status_code,
1212 						   peer_capability, initiator,
1213 						   extra_ies, extra_ies_len);
1214 		break;
1215 	case WLAN_TDLS_DISCOVERY_REQUEST:
1216 		/*
1217 		 * Protect the discovery so we can hear the TDLS discovery
1218 		 * response frame. It is transmitted directly and not buffered
1219 		 * by the AP.
1220 		 */
1221 		drv_mgd_protect_tdls_discover(sdata->local, sdata);
1222 		/* fall-through */
1223 	case WLAN_TDLS_SETUP_CONFIRM:
1224 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1225 		/* no special handling */
1226 		ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1227 						      action_code,
1228 						      dialog_token,
1229 						      status_code,
1230 						      peer_capability,
1231 						      initiator, extra_ies,
1232 						      extra_ies_len, 0, NULL);
1233 		break;
1234 	default:
1235 		ret = -EOPNOTSUPP;
1236 		break;
1237 	}
1238 
1239 	tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1240 		 action_code, peer, ret);
1241 	return ret;
1242 }
1243 
1244 static void iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data *sdata,
1245 					 struct sta_info *sta)
1246 {
1247 	struct ieee80211_local *local = sdata->local;
1248 	struct ieee80211_chanctx_conf *conf;
1249 	struct ieee80211_chanctx *ctx;
1250 	enum nl80211_chan_width width;
1251 	struct ieee80211_supported_band *sband;
1252 
1253 	mutex_lock(&local->chanctx_mtx);
1254 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1255 					 lockdep_is_held(&local->chanctx_mtx));
1256 	if (conf) {
1257 		width = conf->def.width;
1258 		sband = local->hw.wiphy->bands[conf->def.chan->band];
1259 		ctx = container_of(conf, struct ieee80211_chanctx, conf);
1260 		ieee80211_recalc_chanctx_chantype(local, ctx);
1261 
1262 		/* if width changed and a peer is given, update its BW */
1263 		if (width != conf->def.width && sta &&
1264 		    test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW)) {
1265 			enum ieee80211_sta_rx_bandwidth bw;
1266 
1267 			bw = ieee80211_chan_width_to_rx_bw(conf->def.width);
1268 			bw = min(bw, ieee80211_sta_cap_rx_bw(sta));
1269 			if (bw != sta->sta.bandwidth) {
1270 				sta->sta.bandwidth = bw;
1271 				rate_control_rate_update(local, sband, sta,
1272 							 IEEE80211_RC_BW_CHANGED);
1273 				/*
1274 				 * if a TDLS peer BW was updated, we need to
1275 				 * recalc the chandef width again, to get the
1276 				 * correct chanctx min_def
1277 				 */
1278 				ieee80211_recalc_chanctx_chantype(local, ctx);
1279 			}
1280 		}
1281 
1282 	}
1283 	mutex_unlock(&local->chanctx_mtx);
1284 }
1285 
1286 static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
1287 {
1288 	struct sta_info *sta;
1289 	bool result = false;
1290 
1291 	rcu_read_lock();
1292 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1293 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1294 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
1295 		    !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
1296 		    !sta->sta.ht_cap.ht_supported)
1297 			continue;
1298 		result = true;
1299 		break;
1300 	}
1301 	rcu_read_unlock();
1302 
1303 	return result;
1304 }
1305 
1306 static void
1307 iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
1308 				   struct sta_info *sta)
1309 {
1310 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
1311 	bool tdls_ht;
1312 	u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
1313 			 IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
1314 			 IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
1315 	u16 opmode;
1316 
1317 	/* Nothing to do if the BSS connection uses HT */
1318 	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
1319 		return;
1320 
1321 	tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
1322 		  iee80211_tdls_have_ht_peers(sdata);
1323 
1324 	opmode = sdata->vif.bss_conf.ht_operation_mode;
1325 
1326 	if (tdls_ht)
1327 		opmode |= protection;
1328 	else
1329 		opmode &= ~protection;
1330 
1331 	if (opmode == sdata->vif.bss_conf.ht_operation_mode)
1332 		return;
1333 
1334 	sdata->vif.bss_conf.ht_operation_mode = opmode;
1335 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
1336 }
1337 
1338 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1339 			const u8 *peer, enum nl80211_tdls_operation oper)
1340 {
1341 	struct sta_info *sta;
1342 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1343 	struct ieee80211_local *local = sdata->local;
1344 	int ret;
1345 
1346 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1347 		return -ENOTSUPP;
1348 
1349 	if (sdata->vif.type != NL80211_IFTYPE_STATION)
1350 		return -EINVAL;
1351 
1352 	switch (oper) {
1353 	case NL80211_TDLS_ENABLE_LINK:
1354 	case NL80211_TDLS_DISABLE_LINK:
1355 		break;
1356 	case NL80211_TDLS_TEARDOWN:
1357 	case NL80211_TDLS_SETUP:
1358 	case NL80211_TDLS_DISCOVERY_REQ:
1359 		/* We don't support in-driver setup/teardown/discovery */
1360 		return -ENOTSUPP;
1361 	}
1362 
1363 	/* protect possible bss_conf changes and avoid concurrency in
1364 	 * ieee80211_bss_info_change_notify()
1365 	 */
1366 	sdata_lock(sdata);
1367 	mutex_lock(&local->mtx);
1368 	tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1369 
1370 	switch (oper) {
1371 	case NL80211_TDLS_ENABLE_LINK:
1372 		if (sdata->vif.csa_active) {
1373 			tdls_dbg(sdata, "TDLS: disallow link during CSA\n");
1374 			ret = -EBUSY;
1375 			break;
1376 		}
1377 
1378 		mutex_lock(&local->sta_mtx);
1379 		sta = sta_info_get(sdata, peer);
1380 		if (!sta) {
1381 			mutex_unlock(&local->sta_mtx);
1382 			ret = -ENOLINK;
1383 			break;
1384 		}
1385 
1386 		iee80211_tdls_recalc_chanctx(sdata, sta);
1387 		iee80211_tdls_recalc_ht_protection(sdata, sta);
1388 
1389 		set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1390 		mutex_unlock(&local->sta_mtx);
1391 
1392 		WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1393 			     !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1394 		ret = 0;
1395 		break;
1396 	case NL80211_TDLS_DISABLE_LINK:
1397 		/*
1398 		 * The teardown message in ieee80211_tdls_mgmt_teardown() was
1399 		 * created while the queues were stopped, so it might still be
1400 		 * pending. Before flushing the queues we need to be sure the
1401 		 * message is handled by the tasklet handling pending messages,
1402 		 * otherwise we might start destroying the station before
1403 		 * sending the teardown packet.
1404 		 * Note that this only forces the tasklet to flush pendings -
1405 		 * not to stop the tasklet from rescheduling itself.
1406 		 */
1407 		tasklet_kill(&local->tx_pending_tasklet);
1408 		/* flush a potentially queued teardown packet */
1409 		ieee80211_flush_queues(local, sdata, false);
1410 
1411 		ret = sta_info_destroy_addr(sdata, peer);
1412 
1413 		mutex_lock(&local->sta_mtx);
1414 		iee80211_tdls_recalc_ht_protection(sdata, NULL);
1415 		mutex_unlock(&local->sta_mtx);
1416 
1417 		iee80211_tdls_recalc_chanctx(sdata, NULL);
1418 		break;
1419 	default:
1420 		ret = -ENOTSUPP;
1421 		break;
1422 	}
1423 
1424 	if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1425 		cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1426 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1427 	}
1428 
1429 	if (ret == 0)
1430 		ieee80211_queue_work(&sdata->local->hw,
1431 				     &sdata->u.mgd.request_smps_work);
1432 
1433 	mutex_unlock(&local->mtx);
1434 	sdata_unlock(sdata);
1435 	return ret;
1436 }
1437 
1438 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1439 				 enum nl80211_tdls_operation oper,
1440 				 u16 reason_code, gfp_t gfp)
1441 {
1442 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1443 
1444 	if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1445 		sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1446 			  oper);
1447 		return;
1448 	}
1449 
1450 	cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1451 }
1452 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1453 
1454 static void
1455 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1456 {
1457 	struct ieee80211_ch_switch_timing *ch_sw;
1458 
1459 	*buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1460 	*buf++ = sizeof(struct ieee80211_ch_switch_timing);
1461 
1462 	ch_sw = (void *)buf;
1463 	ch_sw->switch_time = cpu_to_le16(switch_time);
1464 	ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1465 }
1466 
1467 /* find switch timing IE in SKB ready for Tx */
1468 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1469 {
1470 	struct ieee80211_tdls_data *tf;
1471 	const u8 *ie_start;
1472 
1473 	/*
1474 	 * Get the offset for the new location of the switch timing IE.
1475 	 * The SKB network header will now point to the "payload_type"
1476 	 * element of the TDLS data frame struct.
1477 	 */
1478 	tf = container_of(skb->data + skb_network_offset(skb),
1479 			  struct ieee80211_tdls_data, payload_type);
1480 	ie_start = tf->u.chan_switch_req.variable;
1481 	return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1482 				skb->len - (ie_start - skb->data));
1483 }
1484 
1485 static struct sk_buff *
1486 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1487 			      struct cfg80211_chan_def *chandef,
1488 			      u32 *ch_sw_tm_ie_offset)
1489 {
1490 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1491 	u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1492 		     2 + sizeof(struct ieee80211_ch_switch_timing)];
1493 	int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1494 	u8 *pos = extra_ies;
1495 	struct sk_buff *skb;
1496 
1497 	/*
1498 	 * if chandef points to a wide channel add a Secondary-Channel
1499 	 * Offset information element
1500 	 */
1501 	if (chandef->width == NL80211_CHAN_WIDTH_40) {
1502 		struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1503 		bool ht40plus;
1504 
1505 		*pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1506 		*pos++ = sizeof(*sec_chan_ie);
1507 		sec_chan_ie = (void *)pos;
1508 
1509 		ht40plus = cfg80211_get_chandef_type(chandef) ==
1510 							NL80211_CHAN_HT40PLUS;
1511 		sec_chan_ie->sec_chan_offs = ht40plus ?
1512 					     IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1513 					     IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1514 		pos += sizeof(*sec_chan_ie);
1515 
1516 		extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1517 	}
1518 
1519 	/* just set the values to 0, this is a template */
1520 	iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1521 
1522 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1523 					      WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1524 					      0, 0, !sta->sta.tdls_initiator,
1525 					      extra_ies, extra_ies_len,
1526 					      oper_class, chandef);
1527 	if (!skb)
1528 		return NULL;
1529 
1530 	skb = ieee80211_build_data_template(sdata, skb, 0);
1531 	if (IS_ERR(skb)) {
1532 		tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1533 		return NULL;
1534 	}
1535 
1536 	if (ch_sw_tm_ie_offset) {
1537 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1538 
1539 		if (!tm_ie) {
1540 			tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1541 			dev_kfree_skb_any(skb);
1542 			return NULL;
1543 		}
1544 
1545 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1546 	}
1547 
1548 	tdls_dbg(sdata,
1549 		 "TDLS channel switch request template for %pM ch %d width %d\n",
1550 		 sta->sta.addr, chandef->chan->center_freq, chandef->width);
1551 	return skb;
1552 }
1553 
1554 int
1555 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1556 			      const u8 *addr, u8 oper_class,
1557 			      struct cfg80211_chan_def *chandef)
1558 {
1559 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1560 	struct ieee80211_local *local = sdata->local;
1561 	struct sta_info *sta;
1562 	struct sk_buff *skb = NULL;
1563 	u32 ch_sw_tm_ie;
1564 	int ret;
1565 
1566 	mutex_lock(&local->sta_mtx);
1567 	sta = sta_info_get(sdata, addr);
1568 	if (!sta) {
1569 		tdls_dbg(sdata,
1570 			 "Invalid TDLS peer %pM for channel switch request\n",
1571 			 addr);
1572 		ret = -ENOENT;
1573 		goto out;
1574 	}
1575 
1576 	if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1577 		tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1578 			 addr);
1579 		ret = -ENOTSUPP;
1580 		goto out;
1581 	}
1582 
1583 	skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1584 					    &ch_sw_tm_ie);
1585 	if (!skb) {
1586 		ret = -ENOENT;
1587 		goto out;
1588 	}
1589 
1590 	ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1591 				      chandef, skb, ch_sw_tm_ie);
1592 	if (!ret)
1593 		set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1594 
1595 out:
1596 	mutex_unlock(&local->sta_mtx);
1597 	dev_kfree_skb_any(skb);
1598 	return ret;
1599 }
1600 
1601 void
1602 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1603 				     struct net_device *dev,
1604 				     const u8 *addr)
1605 {
1606 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1607 	struct ieee80211_local *local = sdata->local;
1608 	struct sta_info *sta;
1609 
1610 	mutex_lock(&local->sta_mtx);
1611 	sta = sta_info_get(sdata, addr);
1612 	if (!sta) {
1613 		tdls_dbg(sdata,
1614 			 "Invalid TDLS peer %pM for channel switch cancel\n",
1615 			 addr);
1616 		goto out;
1617 	}
1618 
1619 	if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1620 		tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1621 			 addr);
1622 		goto out;
1623 	}
1624 
1625 	drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1626 	clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1627 
1628 out:
1629 	mutex_unlock(&local->sta_mtx);
1630 }
1631 
1632 static struct sk_buff *
1633 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1634 				   u32 *ch_sw_tm_ie_offset)
1635 {
1636 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1637 	struct sk_buff *skb;
1638 	u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1639 
1640 	/* initial timing are always zero in the template */
1641 	iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1642 
1643 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1644 					WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1645 					0, 0, !sta->sta.tdls_initiator,
1646 					extra_ies, sizeof(extra_ies), 0, NULL);
1647 	if (!skb)
1648 		return NULL;
1649 
1650 	skb = ieee80211_build_data_template(sdata, skb, 0);
1651 	if (IS_ERR(skb)) {
1652 		tdls_dbg(sdata,
1653 			 "Failed building TDLS channel switch resp frame\n");
1654 		return NULL;
1655 	}
1656 
1657 	if (ch_sw_tm_ie_offset) {
1658 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1659 
1660 		if (!tm_ie) {
1661 			tdls_dbg(sdata,
1662 				 "No switch timing IE in TDLS switch resp\n");
1663 			dev_kfree_skb_any(skb);
1664 			return NULL;
1665 		}
1666 
1667 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1668 	}
1669 
1670 	tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1671 		 sta->sta.addr);
1672 	return skb;
1673 }
1674 
1675 static int
1676 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1677 					   struct sk_buff *skb)
1678 {
1679 	struct ieee80211_local *local = sdata->local;
1680 	struct ieee802_11_elems elems;
1681 	struct sta_info *sta;
1682 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1683 	bool local_initiator;
1684 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1685 	int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1686 	struct ieee80211_tdls_ch_sw_params params = {};
1687 	int ret;
1688 
1689 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1690 	params.timestamp = rx_status->device_timestamp;
1691 
1692 	if (skb->len < baselen) {
1693 		tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1694 			 skb->len);
1695 		return -EINVAL;
1696 	}
1697 
1698 	mutex_lock(&local->sta_mtx);
1699 	sta = sta_info_get(sdata, tf->sa);
1700 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1701 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1702 			 tf->sa);
1703 		ret = -EINVAL;
1704 		goto out;
1705 	}
1706 
1707 	params.sta = &sta->sta;
1708 	params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1709 	if (params.status != 0) {
1710 		ret = 0;
1711 		goto call_drv;
1712 	}
1713 
1714 	ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1715 			       skb->len - baselen, false, &elems);
1716 	if (elems.parse_error) {
1717 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1718 		ret = -EINVAL;
1719 		goto out;
1720 	}
1721 
1722 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1723 		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1724 		ret = -EINVAL;
1725 		goto out;
1726 	}
1727 
1728 	/* validate the initiator is set correctly */
1729 	local_initiator =
1730 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1731 	if (local_initiator == sta->sta.tdls_initiator) {
1732 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1733 		ret = -EINVAL;
1734 		goto out;
1735 	}
1736 
1737 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1738 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1739 
1740 	params.tmpl_skb =
1741 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1742 	if (!params.tmpl_skb) {
1743 		ret = -ENOENT;
1744 		goto out;
1745 	}
1746 
1747 	ret = 0;
1748 call_drv:
1749 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1750 
1751 	tdls_dbg(sdata,
1752 		 "TDLS channel switch response received from %pM status %d\n",
1753 		 tf->sa, params.status);
1754 
1755 out:
1756 	mutex_unlock(&local->sta_mtx);
1757 	dev_kfree_skb_any(params.tmpl_skb);
1758 	return ret;
1759 }
1760 
1761 static int
1762 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1763 					  struct sk_buff *skb)
1764 {
1765 	struct ieee80211_local *local = sdata->local;
1766 	struct ieee802_11_elems elems;
1767 	struct cfg80211_chan_def chandef;
1768 	struct ieee80211_channel *chan;
1769 	enum nl80211_channel_type chan_type;
1770 	int freq;
1771 	u8 target_channel, oper_class;
1772 	bool local_initiator;
1773 	struct sta_info *sta;
1774 	enum nl80211_band band;
1775 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1776 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1777 	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1778 	struct ieee80211_tdls_ch_sw_params params = {};
1779 	int ret = 0;
1780 
1781 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1782 	params.timestamp = rx_status->device_timestamp;
1783 
1784 	if (skb->len < baselen) {
1785 		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1786 			 skb->len);
1787 		return -EINVAL;
1788 	}
1789 
1790 	target_channel = tf->u.chan_switch_req.target_channel;
1791 	oper_class = tf->u.chan_switch_req.oper_class;
1792 
1793 	/*
1794 	 * We can't easily infer the channel band. The operating class is
1795 	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1796 	 * solution here is to treat channels with number >14 as 5GHz ones,
1797 	 * and specifically check for the (oper_class, channel) combinations
1798 	 * where this doesn't hold. These are thankfully unique according to
1799 	 * IEEE802.11-2012.
1800 	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1801 	 * valid here.
1802 	 */
1803 	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1804 	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1805 	     target_channel < 14)
1806 		band = NL80211_BAND_5GHZ;
1807 	else
1808 		band = target_channel < 14 ? NL80211_BAND_2GHZ :
1809 					     NL80211_BAND_5GHZ;
1810 
1811 	freq = ieee80211_channel_to_frequency(target_channel, band);
1812 	if (freq == 0) {
1813 		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1814 			 target_channel);
1815 		return -EINVAL;
1816 	}
1817 
1818 	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1819 	if (!chan) {
1820 		tdls_dbg(sdata,
1821 			 "Unsupported channel for TDLS chan switch: %d\n",
1822 			 target_channel);
1823 		return -EINVAL;
1824 	}
1825 
1826 	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1827 			       skb->len - baselen, false, &elems);
1828 	if (elems.parse_error) {
1829 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1830 		return -EINVAL;
1831 	}
1832 
1833 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1834 		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1835 		return -EINVAL;
1836 	}
1837 
1838 	if (!elems.sec_chan_offs) {
1839 		chan_type = NL80211_CHAN_HT20;
1840 	} else {
1841 		switch (elems.sec_chan_offs->sec_chan_offs) {
1842 		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1843 			chan_type = NL80211_CHAN_HT40PLUS;
1844 			break;
1845 		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1846 			chan_type = NL80211_CHAN_HT40MINUS;
1847 			break;
1848 		default:
1849 			chan_type = NL80211_CHAN_HT20;
1850 			break;
1851 		}
1852 	}
1853 
1854 	cfg80211_chandef_create(&chandef, chan, chan_type);
1855 
1856 	/* we will be active on the TDLS link */
1857 	if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1858 					   sdata->wdev.iftype)) {
1859 		tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1860 		return -EINVAL;
1861 	}
1862 
1863 	mutex_lock(&local->sta_mtx);
1864 	sta = sta_info_get(sdata, tf->sa);
1865 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1866 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1867 			 tf->sa);
1868 		ret = -EINVAL;
1869 		goto out;
1870 	}
1871 
1872 	params.sta = &sta->sta;
1873 
1874 	/* validate the initiator is set correctly */
1875 	local_initiator =
1876 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1877 	if (local_initiator == sta->sta.tdls_initiator) {
1878 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1879 		ret = -EINVAL;
1880 		goto out;
1881 	}
1882 
1883 	/* peer should have known better */
1884 	if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1885 	    elems.sec_chan_offs->sec_chan_offs) {
1886 		tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1887 		ret = -ENOTSUPP;
1888 		goto out;
1889 	}
1890 
1891 	params.chandef = &chandef;
1892 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1893 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1894 
1895 	params.tmpl_skb =
1896 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1897 						   &params.ch_sw_tm_ie);
1898 	if (!params.tmpl_skb) {
1899 		ret = -ENOENT;
1900 		goto out;
1901 	}
1902 
1903 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1904 
1905 	tdls_dbg(sdata,
1906 		 "TDLS ch switch request received from %pM ch %d width %d\n",
1907 		 tf->sa, params.chandef->chan->center_freq,
1908 		 params.chandef->width);
1909 out:
1910 	mutex_unlock(&local->sta_mtx);
1911 	dev_kfree_skb_any(params.tmpl_skb);
1912 	return ret;
1913 }
1914 
1915 static void
1916 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1917 				      struct sk_buff *skb)
1918 {
1919 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1920 	struct wiphy *wiphy = sdata->local->hw.wiphy;
1921 
1922 	ASSERT_RTNL();
1923 
1924 	/* make sure the driver supports it */
1925 	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1926 		return;
1927 
1928 	/* we want to access the entire packet */
1929 	if (skb_linearize(skb))
1930 		return;
1931 	/*
1932 	 * The packet/size was already validated by mac80211 Rx path, only look
1933 	 * at the action type.
1934 	 */
1935 	switch (tf->action_code) {
1936 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1937 		ieee80211_process_tdls_channel_switch_req(sdata, skb);
1938 		break;
1939 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1940 		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1941 		break;
1942 	default:
1943 		WARN_ON_ONCE(1);
1944 		return;
1945 	}
1946 }
1947 
1948 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1949 {
1950 	struct sta_info *sta;
1951 	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1952 
1953 	rcu_read_lock();
1954 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1955 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1956 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1957 			continue;
1958 
1959 		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1960 					    NL80211_TDLS_TEARDOWN, reason,
1961 					    GFP_ATOMIC);
1962 	}
1963 	rcu_read_unlock();
1964 }
1965 
1966 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1967 {
1968 	struct ieee80211_local *local =
1969 		container_of(wk, struct ieee80211_local, tdls_chsw_work);
1970 	struct ieee80211_sub_if_data *sdata;
1971 	struct sk_buff *skb;
1972 	struct ieee80211_tdls_data *tf;
1973 
1974 	rtnl_lock();
1975 	while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1976 		tf = (struct ieee80211_tdls_data *)skb->data;
1977 		list_for_each_entry(sdata, &local->interfaces, list) {
1978 			if (!ieee80211_sdata_running(sdata) ||
1979 			    sdata->vif.type != NL80211_IFTYPE_STATION ||
1980 			    !ether_addr_equal(tf->da, sdata->vif.addr))
1981 				continue;
1982 
1983 			ieee80211_process_tdls_channel_switch(sdata, skb);
1984 			break;
1985 		}
1986 
1987 		kfree_skb(skb);
1988 	}
1989 	rtnl_unlock();
1990 }
1991