xref: /openbmc/linux/net/mac80211/tdls.c (revision 1a59d1b8)
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  * Copyright (C) 2019 Intel Corporation
9  *
10  * This file is GPLv2 as found in COPYING.
11  */
12 
13 #include <linux/ieee80211.h>
14 #include <linux/log2.h>
15 #include <net/cfg80211.h>
16 #include <linux/rtnetlink.h>
17 #include "ieee80211_i.h"
18 #include "driver-ops.h"
19 #include "rate.h"
20 #include "wme.h"
21 
22 /* give usermode some time for retries in setting up the TDLS session */
23 #define TDLS_PEER_SETUP_TIMEOUT	(15 * HZ)
24 
25 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
26 {
27 	struct ieee80211_sub_if_data *sdata;
28 	struct ieee80211_local *local;
29 
30 	sdata = container_of(wk, struct ieee80211_sub_if_data,
31 			     u.mgd.tdls_peer_del_work.work);
32 	local = sdata->local;
33 
34 	mutex_lock(&local->mtx);
35 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
36 		tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
37 		sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
38 		eth_zero_addr(sdata->u.mgd.tdls_peer);
39 	}
40 	mutex_unlock(&local->mtx);
41 }
42 
43 static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
44 					 struct sk_buff *skb)
45 {
46 	struct ieee80211_local *local = sdata->local;
47 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
48 	bool chan_switch = local->hw.wiphy->features &
49 			   NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
50 	bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW) &&
51 			  !ifmgd->tdls_wider_bw_prohibited;
52 	bool buffer_sta = ieee80211_hw_check(&local->hw,
53 					     SUPPORTS_TDLS_BUFFER_STA);
54 	struct ieee80211_supported_band *sband = ieee80211_get_sband(sdata);
55 	bool vht = sband && sband->vht_cap.vht_supported;
56 	u8 *pos = skb_put(skb, 10);
57 
58 	*pos++ = WLAN_EID_EXT_CAPABILITY;
59 	*pos++ = 8; /* len */
60 	*pos++ = 0x0;
61 	*pos++ = 0x0;
62 	*pos++ = 0x0;
63 	*pos++ = (chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0) |
64 		 (buffer_sta ? WLAN_EXT_CAPA4_TDLS_BUFFER_STA : 0);
65 	*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
66 	*pos++ = 0;
67 	*pos++ = 0;
68 	*pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
69 }
70 
71 static u8
72 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
73 			   struct sk_buff *skb, u16 start, u16 end,
74 			   u16 spacing)
75 {
76 	u8 subband_cnt = 0, ch_cnt = 0;
77 	struct ieee80211_channel *ch;
78 	struct cfg80211_chan_def chandef;
79 	int i, subband_start;
80 	struct wiphy *wiphy = sdata->local->hw.wiphy;
81 
82 	for (i = start; i <= end; i += spacing) {
83 		if (!ch_cnt)
84 			subband_start = i;
85 
86 		ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
87 		if (ch) {
88 			/* we will be active on the channel */
89 			cfg80211_chandef_create(&chandef, ch,
90 						NL80211_CHAN_NO_HT);
91 			if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
92 							  sdata->wdev.iftype)) {
93 				ch_cnt++;
94 				/*
95 				 * check if the next channel is also part of
96 				 * this allowed range
97 				 */
98 				continue;
99 			}
100 		}
101 
102 		/*
103 		 * we've reached the end of a range, with allowed channels
104 		 * found
105 		 */
106 		if (ch_cnt) {
107 			u8 *pos = skb_put(skb, 2);
108 			*pos++ = ieee80211_frequency_to_channel(subband_start);
109 			*pos++ = ch_cnt;
110 
111 			subband_cnt++;
112 			ch_cnt = 0;
113 		}
114 	}
115 
116 	/* all channels in the requested range are allowed - add them here */
117 	if (ch_cnt) {
118 		u8 *pos = skb_put(skb, 2);
119 		*pos++ = ieee80211_frequency_to_channel(subband_start);
120 		*pos++ = ch_cnt;
121 
122 		subband_cnt++;
123 	}
124 
125 	return subband_cnt;
126 }
127 
128 static void
129 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
130 				 struct sk_buff *skb)
131 {
132 	/*
133 	 * Add possible channels for TDLS. These are channels that are allowed
134 	 * to be active.
135 	 */
136 	u8 subband_cnt;
137 	u8 *pos = skb_put(skb, 2);
138 
139 	*pos++ = WLAN_EID_SUPPORTED_CHANNELS;
140 
141 	/*
142 	 * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
143 	 * this doesn't happen in real world scenarios.
144 	 */
145 
146 	/* 2GHz, with 5MHz spacing */
147 	subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
148 
149 	/* 5GHz, with 20MHz spacing */
150 	subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
151 
152 	/* length */
153 	*pos = 2 * subband_cnt;
154 }
155 
156 static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
157 					    struct sk_buff *skb)
158 {
159 	u8 *pos;
160 	u8 op_class;
161 
162 	if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
163 						  &op_class))
164 		return;
165 
166 	pos = skb_put(skb, 4);
167 	*pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
168 	*pos++ = 2; /* len */
169 
170 	*pos++ = op_class;
171 	*pos++ = op_class; /* give current operating class as alternate too */
172 }
173 
174 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
175 {
176 	u8 *pos = skb_put(skb, 3);
177 
178 	*pos++ = WLAN_EID_BSS_COEX_2040;
179 	*pos++ = 1; /* len */
180 
181 	*pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
182 }
183 
184 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
185 					u16 status_code)
186 {
187 	struct ieee80211_supported_band *sband;
188 
189 	/* The capability will be 0 when sending a failure code */
190 	if (status_code != 0)
191 		return 0;
192 
193 	sband = ieee80211_get_sband(sdata);
194 	if (sband && sband->band == NL80211_BAND_2GHZ) {
195 		return WLAN_CAPABILITY_SHORT_SLOT_TIME |
196 		       WLAN_CAPABILITY_SHORT_PREAMBLE;
197 	}
198 
199 	return 0;
200 }
201 
202 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
203 				       struct sk_buff *skb, const u8 *peer,
204 				       bool initiator)
205 {
206 	struct ieee80211_tdls_lnkie *lnkid;
207 	const u8 *init_addr, *rsp_addr;
208 
209 	if (initiator) {
210 		init_addr = sdata->vif.addr;
211 		rsp_addr = peer;
212 	} else {
213 		init_addr = peer;
214 		rsp_addr = sdata->vif.addr;
215 	}
216 
217 	lnkid = skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
218 
219 	lnkid->ie_type = WLAN_EID_LINK_ID;
220 	lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
221 
222 	memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
223 	memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
224 	memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
225 }
226 
227 static void
228 ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
229 {
230 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
231 	u8 *pos = skb_put(skb, 4);
232 
233 	*pos++ = WLAN_EID_AID;
234 	*pos++ = 2; /* len */
235 	put_unaligned_le16(ifmgd->aid, pos);
236 }
237 
238 /* translate numbering in the WMM parameter IE to the mac80211 notation */
239 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
240 {
241 	switch (ac) {
242 	default:
243 		WARN_ON_ONCE(1);
244 		/* fall through */
245 	case 0:
246 		return IEEE80211_AC_BE;
247 	case 1:
248 		return IEEE80211_AC_BK;
249 	case 2:
250 		return IEEE80211_AC_VI;
251 	case 3:
252 		return IEEE80211_AC_VO;
253 	}
254 }
255 
256 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
257 {
258 	u8 ret;
259 
260 	ret = aifsn & 0x0f;
261 	if (acm)
262 		ret |= 0x10;
263 	ret |= (aci << 5) & 0x60;
264 	return ret;
265 }
266 
267 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
268 {
269 	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
270 	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
271 }
272 
273 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
274 					    struct sk_buff *skb)
275 {
276 	struct ieee80211_wmm_param_ie *wmm;
277 	struct ieee80211_tx_queue_params *txq;
278 	int i;
279 
280 	wmm = skb_put_zero(skb, sizeof(*wmm));
281 
282 	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
283 	wmm->len = sizeof(*wmm) - 2;
284 
285 	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
286 	wmm->oui[1] = 0x50;
287 	wmm->oui[2] = 0xf2;
288 	wmm->oui_type = 2; /* WME */
289 	wmm->oui_subtype = 1; /* WME param */
290 	wmm->version = 1; /* WME ver */
291 	wmm->qos_info = 0; /* U-APSD not in use */
292 
293 	/*
294 	 * Use the EDCA parameters defined for the BSS, or default if the AP
295 	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
296 	 */
297 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
298 		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
299 		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
300 							       txq->acm, i);
301 		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
302 		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
303 	}
304 }
305 
306 static void
307 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
308 				   struct sta_info *sta)
309 {
310 	/* IEEE802.11ac-2013 Table E-4 */
311 	u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
312 	struct cfg80211_chan_def uc = sta->tdls_chandef;
313 	enum nl80211_chan_width max_width = ieee80211_sta_cap_chan_bw(sta);
314 	int i;
315 
316 	/* only support upgrading non-narrow channels up to 80Mhz */
317 	if (max_width == NL80211_CHAN_WIDTH_5 ||
318 	    max_width == NL80211_CHAN_WIDTH_10)
319 		return;
320 
321 	if (max_width > NL80211_CHAN_WIDTH_80)
322 		max_width = NL80211_CHAN_WIDTH_80;
323 
324 	if (uc.width >= max_width)
325 		return;
326 	/*
327 	 * Channel usage constrains in the IEEE802.11ac-2013 specification only
328 	 * allow expanding a 20MHz channel to 80MHz in a single way. In
329 	 * addition, there are no 40MHz allowed channels that are not part of
330 	 * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
331 	 */
332 	for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
333 		if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
334 			uc.center_freq1 = centers_80mhz[i];
335 			uc.center_freq2 = 0;
336 			uc.width = NL80211_CHAN_WIDTH_80;
337 			break;
338 		}
339 
340 	if (!uc.center_freq1)
341 		return;
342 
343 	/* proceed to downgrade the chandef until usable or the same as AP BW */
344 	while (uc.width > max_width ||
345 	       (uc.width > sta->tdls_chandef.width &&
346 		!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &uc,
347 					       sdata->wdev.iftype)))
348 		ieee80211_chandef_downgrade(&uc);
349 
350 	if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
351 		tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
352 			 sta->tdls_chandef.width, uc.width);
353 
354 		/*
355 		 * the station is not yet authorized when BW upgrade is done,
356 		 * locking is not required
357 		 */
358 		sta->tdls_chandef = uc;
359 	}
360 }
361 
362 static void
363 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
364 				   struct sk_buff *skb, const u8 *peer,
365 				   u8 action_code, bool initiator,
366 				   const u8 *extra_ies, size_t extra_ies_len)
367 {
368 	struct ieee80211_supported_band *sband;
369 	struct ieee80211_local *local = sdata->local;
370 	struct ieee80211_sta_ht_cap ht_cap;
371 	struct ieee80211_sta_vht_cap vht_cap;
372 	struct sta_info *sta = NULL;
373 	size_t offset = 0, noffset;
374 	u8 *pos;
375 
376 	sband = ieee80211_get_sband(sdata);
377 	if (!sband)
378 		return;
379 
380 	ieee80211_add_srates_ie(sdata, skb, false, sband->band);
381 	ieee80211_add_ext_srates_ie(sdata, skb, false, sband->band);
382 	ieee80211_tdls_add_supp_channels(sdata, skb);
383 
384 	/* add any custom IEs that go before Extended Capabilities */
385 	if (extra_ies_len) {
386 		static const u8 before_ext_cap[] = {
387 			WLAN_EID_SUPP_RATES,
388 			WLAN_EID_COUNTRY,
389 			WLAN_EID_EXT_SUPP_RATES,
390 			WLAN_EID_SUPPORTED_CHANNELS,
391 			WLAN_EID_RSN,
392 		};
393 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
394 					     before_ext_cap,
395 					     ARRAY_SIZE(before_ext_cap),
396 					     offset);
397 		skb_put_data(skb, extra_ies + offset, noffset - offset);
398 		offset = noffset;
399 	}
400 
401 	ieee80211_tdls_add_ext_capab(sdata, skb);
402 
403 	/* add the QoS element if we support it */
404 	if (local->hw.queues >= IEEE80211_NUM_ACS &&
405 	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
406 		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
407 
408 	/* add any custom IEs that go before HT capabilities */
409 	if (extra_ies_len) {
410 		static const u8 before_ht_cap[] = {
411 			WLAN_EID_SUPP_RATES,
412 			WLAN_EID_COUNTRY,
413 			WLAN_EID_EXT_SUPP_RATES,
414 			WLAN_EID_SUPPORTED_CHANNELS,
415 			WLAN_EID_RSN,
416 			WLAN_EID_EXT_CAPABILITY,
417 			WLAN_EID_QOS_CAPA,
418 			WLAN_EID_FAST_BSS_TRANSITION,
419 			WLAN_EID_TIMEOUT_INTERVAL,
420 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
421 		};
422 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
423 					     before_ht_cap,
424 					     ARRAY_SIZE(before_ht_cap),
425 					     offset);
426 		skb_put_data(skb, extra_ies + offset, noffset - offset);
427 		offset = noffset;
428 	}
429 
430 	mutex_lock(&local->sta_mtx);
431 
432 	/* we should have the peer STA if we're already responding */
433 	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
434 		sta = sta_info_get(sdata, peer);
435 		if (WARN_ON_ONCE(!sta)) {
436 			mutex_unlock(&local->sta_mtx);
437 			return;
438 		}
439 
440 		sta->tdls_chandef = sdata->vif.bss_conf.chandef;
441 	}
442 
443 	ieee80211_tdls_add_oper_classes(sdata, skb);
444 
445 	/*
446 	 * with TDLS we can switch channels, and HT-caps are not necessarily
447 	 * the same on all bands. The specification limits the setup to a
448 	 * single HT-cap, so use the current band for now.
449 	 */
450 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
451 
452 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
453 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
454 	    ht_cap.ht_supported) {
455 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
456 
457 		/* disable SMPS in TDLS initiator */
458 		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
459 				<< IEEE80211_HT_CAP_SM_PS_SHIFT;
460 
461 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
462 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
463 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
464 		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
465 		/* the peer caps are already intersected with our own */
466 		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
467 
468 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
469 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
470 	}
471 
472 	if (ht_cap.ht_supported &&
473 	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
474 		ieee80211_tdls_add_bss_coex_ie(skb);
475 
476 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
477 
478 	/* add any custom IEs that go before VHT capabilities */
479 	if (extra_ies_len) {
480 		static const u8 before_vht_cap[] = {
481 			WLAN_EID_SUPP_RATES,
482 			WLAN_EID_COUNTRY,
483 			WLAN_EID_EXT_SUPP_RATES,
484 			WLAN_EID_SUPPORTED_CHANNELS,
485 			WLAN_EID_RSN,
486 			WLAN_EID_EXT_CAPABILITY,
487 			WLAN_EID_QOS_CAPA,
488 			WLAN_EID_FAST_BSS_TRANSITION,
489 			WLAN_EID_TIMEOUT_INTERVAL,
490 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
491 			WLAN_EID_MULTI_BAND,
492 		};
493 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
494 					     before_vht_cap,
495 					     ARRAY_SIZE(before_vht_cap),
496 					     offset);
497 		skb_put_data(skb, extra_ies + offset, noffset - offset);
498 		offset = noffset;
499 	}
500 
501 	/* build the VHT-cap similarly to the HT-cap */
502 	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
503 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
504 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
505 	    vht_cap.vht_supported) {
506 		ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
507 
508 		/* the AID is present only when VHT is implemented */
509 		if (action_code == WLAN_TDLS_SETUP_REQUEST)
510 			ieee80211_tdls_add_aid(sdata, skb);
511 
512 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
513 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
514 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
515 		   vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
516 		/* the peer caps are already intersected with our own */
517 		memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
518 
519 		/* the AID is present only when VHT is implemented */
520 		ieee80211_tdls_add_aid(sdata, skb);
521 
522 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
523 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
524 
525 		/*
526 		 * if both peers support WIDER_BW, we can expand the chandef to
527 		 * a wider compatible one, up to 80MHz
528 		 */
529 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
530 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
531 	}
532 
533 	mutex_unlock(&local->sta_mtx);
534 
535 	/* add any remaining IEs */
536 	if (extra_ies_len) {
537 		noffset = extra_ies_len;
538 		skb_put_data(skb, extra_ies + offset, noffset - offset);
539 	}
540 
541 }
542 
543 static void
544 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
545 				 struct sk_buff *skb, const u8 *peer,
546 				 bool initiator, const u8 *extra_ies,
547 				 size_t extra_ies_len)
548 {
549 	struct ieee80211_local *local = sdata->local;
550 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
551 	size_t offset = 0, noffset;
552 	struct sta_info *sta, *ap_sta;
553 	struct ieee80211_supported_band *sband;
554 	u8 *pos;
555 
556 	sband = ieee80211_get_sband(sdata);
557 	if (!sband)
558 		return;
559 
560 	mutex_lock(&local->sta_mtx);
561 
562 	sta = sta_info_get(sdata, peer);
563 	ap_sta = sta_info_get(sdata, ifmgd->bssid);
564 	if (WARN_ON_ONCE(!sta || !ap_sta)) {
565 		mutex_unlock(&local->sta_mtx);
566 		return;
567 	}
568 
569 	sta->tdls_chandef = sdata->vif.bss_conf.chandef;
570 
571 	/* add any custom IEs that go before the QoS IE */
572 	if (extra_ies_len) {
573 		static const u8 before_qos[] = {
574 			WLAN_EID_RSN,
575 		};
576 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
577 					     before_qos,
578 					     ARRAY_SIZE(before_qos),
579 					     offset);
580 		skb_put_data(skb, extra_ies + offset, noffset - offset);
581 		offset = noffset;
582 	}
583 
584 	/* add the QoS param IE if both the peer and we support it */
585 	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
586 		ieee80211_tdls_add_wmm_param_ie(sdata, skb);
587 
588 	/* add any custom IEs that go before HT operation */
589 	if (extra_ies_len) {
590 		static const u8 before_ht_op[] = {
591 			WLAN_EID_RSN,
592 			WLAN_EID_QOS_CAPA,
593 			WLAN_EID_FAST_BSS_TRANSITION,
594 			WLAN_EID_TIMEOUT_INTERVAL,
595 		};
596 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
597 					     before_ht_op,
598 					     ARRAY_SIZE(before_ht_op),
599 					     offset);
600 		skb_put_data(skb, extra_ies + offset, noffset - offset);
601 		offset = noffset;
602 	}
603 
604 	/*
605 	 * if HT support is only added in TDLS, we need an HT-operation IE.
606 	 * add the IE as required by IEEE802.11-2012 9.23.3.2.
607 	 */
608 	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
609 		u16 prot = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
610 			   IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
611 			   IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
612 
613 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
614 		ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
615 					   &sdata->vif.bss_conf.chandef, prot,
616 					   true);
617 	}
618 
619 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
620 
621 	/* only include VHT-operation if not on the 2.4GHz band */
622 	if (sband->band != NL80211_BAND_2GHZ &&
623 	    sta->sta.vht_cap.vht_supported) {
624 		/*
625 		 * if both peers support WIDER_BW, we can expand the chandef to
626 		 * a wider compatible one, up to 80MHz
627 		 */
628 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
629 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
630 
631 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
632 		ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
633 					    &sta->tdls_chandef);
634 	}
635 
636 	mutex_unlock(&local->sta_mtx);
637 
638 	/* add any remaining IEs */
639 	if (extra_ies_len) {
640 		noffset = extra_ies_len;
641 		skb_put_data(skb, extra_ies + offset, noffset - offset);
642 	}
643 }
644 
645 static void
646 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
647 				       struct sk_buff *skb, const u8 *peer,
648 				       bool initiator, const u8 *extra_ies,
649 				       size_t extra_ies_len, u8 oper_class,
650 				       struct cfg80211_chan_def *chandef)
651 {
652 	struct ieee80211_tdls_data *tf;
653 	size_t offset = 0, noffset;
654 
655 	if (WARN_ON_ONCE(!chandef))
656 		return;
657 
658 	tf = (void *)skb->data;
659 	tf->u.chan_switch_req.target_channel =
660 		ieee80211_frequency_to_channel(chandef->chan->center_freq);
661 	tf->u.chan_switch_req.oper_class = oper_class;
662 
663 	if (extra_ies_len) {
664 		static const u8 before_lnkie[] = {
665 			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
666 		};
667 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
668 					     before_lnkie,
669 					     ARRAY_SIZE(before_lnkie),
670 					     offset);
671 		skb_put_data(skb, extra_ies + offset, noffset - offset);
672 		offset = noffset;
673 	}
674 
675 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
676 
677 	/* add any remaining IEs */
678 	if (extra_ies_len) {
679 		noffset = extra_ies_len;
680 		skb_put_data(skb, extra_ies + offset, noffset - offset);
681 	}
682 }
683 
684 static void
685 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
686 					struct sk_buff *skb, const u8 *peer,
687 					u16 status_code, bool initiator,
688 					const u8 *extra_ies,
689 					size_t extra_ies_len)
690 {
691 	if (status_code == 0)
692 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
693 
694 	if (extra_ies_len)
695 		skb_put_data(skb, extra_ies, extra_ies_len);
696 }
697 
698 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
699 				   struct sk_buff *skb, const u8 *peer,
700 				   u8 action_code, u16 status_code,
701 				   bool initiator, const u8 *extra_ies,
702 				   size_t extra_ies_len, u8 oper_class,
703 				   struct cfg80211_chan_def *chandef)
704 {
705 	switch (action_code) {
706 	case WLAN_TDLS_SETUP_REQUEST:
707 	case WLAN_TDLS_SETUP_RESPONSE:
708 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
709 		if (status_code == 0)
710 			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
711 							   action_code,
712 							   initiator,
713 							   extra_ies,
714 							   extra_ies_len);
715 		break;
716 	case WLAN_TDLS_SETUP_CONFIRM:
717 		if (status_code == 0)
718 			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
719 							 initiator, extra_ies,
720 							 extra_ies_len);
721 		break;
722 	case WLAN_TDLS_TEARDOWN:
723 	case WLAN_TDLS_DISCOVERY_REQUEST:
724 		if (extra_ies_len)
725 			skb_put_data(skb, extra_ies, extra_ies_len);
726 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
727 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
728 		break;
729 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
730 		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
731 						       initiator, extra_ies,
732 						       extra_ies_len,
733 						       oper_class, chandef);
734 		break;
735 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
736 		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
737 							status_code,
738 							initiator, extra_ies,
739 							extra_ies_len);
740 		break;
741 	}
742 
743 }
744 
745 static int
746 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
747 			       const u8 *peer, u8 action_code, u8 dialog_token,
748 			       u16 status_code, struct sk_buff *skb)
749 {
750 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
751 	struct ieee80211_tdls_data *tf;
752 
753 	tf = skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
754 
755 	memcpy(tf->da, peer, ETH_ALEN);
756 	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
757 	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
758 	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
759 
760 	/* network header is after the ethernet header */
761 	skb_set_network_header(skb, ETH_HLEN);
762 
763 	switch (action_code) {
764 	case WLAN_TDLS_SETUP_REQUEST:
765 		tf->category = WLAN_CATEGORY_TDLS;
766 		tf->action_code = WLAN_TDLS_SETUP_REQUEST;
767 
768 		skb_put(skb, sizeof(tf->u.setup_req));
769 		tf->u.setup_req.dialog_token = dialog_token;
770 		tf->u.setup_req.capability =
771 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
772 								 status_code));
773 		break;
774 	case WLAN_TDLS_SETUP_RESPONSE:
775 		tf->category = WLAN_CATEGORY_TDLS;
776 		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
777 
778 		skb_put(skb, sizeof(tf->u.setup_resp));
779 		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
780 		tf->u.setup_resp.dialog_token = dialog_token;
781 		tf->u.setup_resp.capability =
782 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
783 								 status_code));
784 		break;
785 	case WLAN_TDLS_SETUP_CONFIRM:
786 		tf->category = WLAN_CATEGORY_TDLS;
787 		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
788 
789 		skb_put(skb, sizeof(tf->u.setup_cfm));
790 		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
791 		tf->u.setup_cfm.dialog_token = dialog_token;
792 		break;
793 	case WLAN_TDLS_TEARDOWN:
794 		tf->category = WLAN_CATEGORY_TDLS;
795 		tf->action_code = WLAN_TDLS_TEARDOWN;
796 
797 		skb_put(skb, sizeof(tf->u.teardown));
798 		tf->u.teardown.reason_code = cpu_to_le16(status_code);
799 		break;
800 	case WLAN_TDLS_DISCOVERY_REQUEST:
801 		tf->category = WLAN_CATEGORY_TDLS;
802 		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
803 
804 		skb_put(skb, sizeof(tf->u.discover_req));
805 		tf->u.discover_req.dialog_token = dialog_token;
806 		break;
807 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
808 		tf->category = WLAN_CATEGORY_TDLS;
809 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
810 
811 		skb_put(skb, sizeof(tf->u.chan_switch_req));
812 		break;
813 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
814 		tf->category = WLAN_CATEGORY_TDLS;
815 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
816 
817 		skb_put(skb, sizeof(tf->u.chan_switch_resp));
818 		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
819 		break;
820 	default:
821 		return -EINVAL;
822 	}
823 
824 	return 0;
825 }
826 
827 static int
828 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
829 			   const u8 *peer, u8 action_code, u8 dialog_token,
830 			   u16 status_code, struct sk_buff *skb)
831 {
832 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
833 	struct ieee80211_mgmt *mgmt;
834 
835 	mgmt = skb_put_zero(skb, 24);
836 	memcpy(mgmt->da, peer, ETH_ALEN);
837 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
838 	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
839 
840 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
841 					  IEEE80211_STYPE_ACTION);
842 
843 	switch (action_code) {
844 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
845 		skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
846 		mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
847 		mgmt->u.action.u.tdls_discover_resp.action_code =
848 			WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
849 		mgmt->u.action.u.tdls_discover_resp.dialog_token =
850 			dialog_token;
851 		mgmt->u.action.u.tdls_discover_resp.capability =
852 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
853 								 status_code));
854 		break;
855 	default:
856 		return -EINVAL;
857 	}
858 
859 	return 0;
860 }
861 
862 static struct sk_buff *
863 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
864 				      const u8 *peer, u8 action_code,
865 				      u8 dialog_token, u16 status_code,
866 				      bool initiator, const u8 *extra_ies,
867 				      size_t extra_ies_len, u8 oper_class,
868 				      struct cfg80211_chan_def *chandef)
869 {
870 	struct ieee80211_local *local = sdata->local;
871 	struct sk_buff *skb;
872 	int ret;
873 
874 	skb = netdev_alloc_skb(sdata->dev,
875 			       local->hw.extra_tx_headroom +
876 			       max(sizeof(struct ieee80211_mgmt),
877 				   sizeof(struct ieee80211_tdls_data)) +
878 			       50 + /* supported rates */
879 			       10 + /* ext capab */
880 			       26 + /* max(WMM-info, WMM-param) */
881 			       2 + max(sizeof(struct ieee80211_ht_cap),
882 				       sizeof(struct ieee80211_ht_operation)) +
883 			       2 + max(sizeof(struct ieee80211_vht_cap),
884 				       sizeof(struct ieee80211_vht_operation)) +
885 			       50 + /* supported channels */
886 			       3 + /* 40/20 BSS coex */
887 			       4 + /* AID */
888 			       4 + /* oper classes */
889 			       extra_ies_len +
890 			       sizeof(struct ieee80211_tdls_lnkie));
891 	if (!skb)
892 		return NULL;
893 
894 	skb_reserve(skb, local->hw.extra_tx_headroom);
895 
896 	switch (action_code) {
897 	case WLAN_TDLS_SETUP_REQUEST:
898 	case WLAN_TDLS_SETUP_RESPONSE:
899 	case WLAN_TDLS_SETUP_CONFIRM:
900 	case WLAN_TDLS_TEARDOWN:
901 	case WLAN_TDLS_DISCOVERY_REQUEST:
902 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
903 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
904 		ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
905 						     sdata->dev, peer,
906 						     action_code, dialog_token,
907 						     status_code, skb);
908 		break;
909 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
910 		ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
911 						 peer, action_code,
912 						 dialog_token, status_code,
913 						 skb);
914 		break;
915 	default:
916 		ret = -ENOTSUPP;
917 		break;
918 	}
919 
920 	if (ret < 0)
921 		goto fail;
922 
923 	ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
924 			       initiator, extra_ies, extra_ies_len, oper_class,
925 			       chandef);
926 	return skb;
927 
928 fail:
929 	dev_kfree_skb(skb);
930 	return NULL;
931 }
932 
933 static int
934 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
935 				const u8 *peer, u8 action_code, u8 dialog_token,
936 				u16 status_code, u32 peer_capability,
937 				bool initiator, const u8 *extra_ies,
938 				size_t extra_ies_len, u8 oper_class,
939 				struct cfg80211_chan_def *chandef)
940 {
941 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
942 	struct sk_buff *skb = NULL;
943 	struct sta_info *sta;
944 	u32 flags = 0;
945 	int ret = 0;
946 
947 	rcu_read_lock();
948 	sta = sta_info_get(sdata, peer);
949 
950 	/* infer the initiator if we can, to support old userspace */
951 	switch (action_code) {
952 	case WLAN_TDLS_SETUP_REQUEST:
953 		if (sta) {
954 			set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
955 			sta->sta.tdls_initiator = false;
956 		}
957 		/* fall-through */
958 	case WLAN_TDLS_SETUP_CONFIRM:
959 	case WLAN_TDLS_DISCOVERY_REQUEST:
960 		initiator = true;
961 		break;
962 	case WLAN_TDLS_SETUP_RESPONSE:
963 		/*
964 		 * In some testing scenarios, we send a request and response.
965 		 * Make the last packet sent take effect for the initiator
966 		 * value.
967 		 */
968 		if (sta) {
969 			clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
970 			sta->sta.tdls_initiator = true;
971 		}
972 		/* fall-through */
973 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
974 		initiator = false;
975 		break;
976 	case WLAN_TDLS_TEARDOWN:
977 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
978 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
979 		/* any value is ok */
980 		break;
981 	default:
982 		ret = -ENOTSUPP;
983 		break;
984 	}
985 
986 	if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
987 		initiator = true;
988 
989 	rcu_read_unlock();
990 	if (ret < 0)
991 		goto fail;
992 
993 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
994 						    dialog_token, status_code,
995 						    initiator, extra_ies,
996 						    extra_ies_len, oper_class,
997 						    chandef);
998 	if (!skb) {
999 		ret = -EINVAL;
1000 		goto fail;
1001 	}
1002 
1003 	if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
1004 		ieee80211_tx_skb(sdata, skb);
1005 		return 0;
1006 	}
1007 
1008 	/*
1009 	 * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
1010 	 * we should default to AC_VI.
1011 	 */
1012 	switch (action_code) {
1013 	case WLAN_TDLS_SETUP_REQUEST:
1014 	case WLAN_TDLS_SETUP_RESPONSE:
1015 		skb->priority = 256 + 2;
1016 		break;
1017 	default:
1018 		skb->priority = 256 + 5;
1019 		break;
1020 	}
1021 	skb_set_queue_mapping(skb, ieee80211_select_queue(sdata, skb));
1022 
1023 	/*
1024 	 * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
1025 	 * Later, if no ACK is returned from peer, we will re-send the teardown
1026 	 * packet through the AP.
1027 	 */
1028 	if ((action_code == WLAN_TDLS_TEARDOWN) &&
1029 	    ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
1030 		bool try_resend; /* Should we keep skb for possible resend */
1031 
1032 		/* If not sending directly to peer - no point in keeping skb */
1033 		rcu_read_lock();
1034 		sta = sta_info_get(sdata, peer);
1035 		try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1036 		rcu_read_unlock();
1037 
1038 		spin_lock_bh(&sdata->u.mgd.teardown_lock);
1039 		if (try_resend && !sdata->u.mgd.teardown_skb) {
1040 			/* Mark it as requiring TX status callback  */
1041 			flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
1042 				 IEEE80211_TX_INTFL_MLME_CONN_TX;
1043 
1044 			/*
1045 			 * skb is copied since mac80211 will later set
1046 			 * properties that might not be the same as the AP,
1047 			 * such as encryption, QoS, addresses, etc.
1048 			 *
1049 			 * No problem if skb_copy() fails, so no need to check.
1050 			 */
1051 			sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
1052 			sdata->u.mgd.orig_teardown_skb = skb;
1053 		}
1054 		spin_unlock_bh(&sdata->u.mgd.teardown_lock);
1055 	}
1056 
1057 	/* disable bottom halves when entering the Tx path */
1058 	local_bh_disable();
1059 	__ieee80211_subif_start_xmit(skb, dev, flags, 0);
1060 	local_bh_enable();
1061 
1062 	return ret;
1063 
1064 fail:
1065 	dev_kfree_skb(skb);
1066 	return ret;
1067 }
1068 
1069 static int
1070 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
1071 			  const u8 *peer, u8 action_code, u8 dialog_token,
1072 			  u16 status_code, u32 peer_capability, bool initiator,
1073 			  const u8 *extra_ies, size_t extra_ies_len)
1074 {
1075 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1076 	struct ieee80211_local *local = sdata->local;
1077 	enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
1078 	int ret;
1079 
1080 	/* don't support setup with forced SMPS mode that's not off */
1081 	if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
1082 	    smps_mode != IEEE80211_SMPS_OFF) {
1083 		tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
1084 			 smps_mode);
1085 		return -ENOTSUPP;
1086 	}
1087 
1088 	mutex_lock(&local->mtx);
1089 
1090 	/* we don't support concurrent TDLS peer setups */
1091 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
1092 	    !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1093 		ret = -EBUSY;
1094 		goto out_unlock;
1095 	}
1096 
1097 	/*
1098 	 * make sure we have a STA representing the peer so we drop or buffer
1099 	 * non-TDLS-setup frames to the peer. We can't send other packets
1100 	 * during setup through the AP path.
1101 	 * Allow error packets to be sent - sometimes we don't even add a STA
1102 	 * before failing the setup.
1103 	 */
1104 	if (status_code == 0) {
1105 		rcu_read_lock();
1106 		if (!sta_info_get(sdata, peer)) {
1107 			rcu_read_unlock();
1108 			ret = -ENOLINK;
1109 			goto out_unlock;
1110 		}
1111 		rcu_read_unlock();
1112 	}
1113 
1114 	ieee80211_flush_queues(local, sdata, false);
1115 	memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
1116 	mutex_unlock(&local->mtx);
1117 
1118 	/* we cannot take the mutex while preparing the setup packet */
1119 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1120 					      dialog_token, status_code,
1121 					      peer_capability, initiator,
1122 					      extra_ies, extra_ies_len, 0,
1123 					      NULL);
1124 	if (ret < 0) {
1125 		mutex_lock(&local->mtx);
1126 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1127 		mutex_unlock(&local->mtx);
1128 		return ret;
1129 	}
1130 
1131 	ieee80211_queue_delayed_work(&sdata->local->hw,
1132 				     &sdata->u.mgd.tdls_peer_del_work,
1133 				     TDLS_PEER_SETUP_TIMEOUT);
1134 	return 0;
1135 
1136 out_unlock:
1137 	mutex_unlock(&local->mtx);
1138 	return ret;
1139 }
1140 
1141 static int
1142 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
1143 			     const u8 *peer, u8 action_code, u8 dialog_token,
1144 			     u16 status_code, u32 peer_capability,
1145 			     bool initiator, const u8 *extra_ies,
1146 			     size_t extra_ies_len)
1147 {
1148 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1149 	struct ieee80211_local *local = sdata->local;
1150 	struct sta_info *sta;
1151 	int ret;
1152 
1153 	/*
1154 	 * No packets can be transmitted to the peer via the AP during setup -
1155 	 * the STA is set as a TDLS peer, but is not authorized.
1156 	 * During teardown, we prevent direct transmissions by stopping the
1157 	 * queues and flushing all direct packets.
1158 	 */
1159 	ieee80211_stop_vif_queues(local, sdata,
1160 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1161 	ieee80211_flush_queues(local, sdata, false);
1162 
1163 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1164 					      dialog_token, status_code,
1165 					      peer_capability, initiator,
1166 					      extra_ies, extra_ies_len, 0,
1167 					      NULL);
1168 	if (ret < 0)
1169 		sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
1170 			  ret);
1171 
1172 	/*
1173 	 * Remove the STA AUTH flag to force further traffic through the AP. If
1174 	 * the STA was unreachable, it was already removed.
1175 	 */
1176 	rcu_read_lock();
1177 	sta = sta_info_get(sdata, peer);
1178 	if (sta)
1179 		clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1180 	rcu_read_unlock();
1181 
1182 	ieee80211_wake_vif_queues(local, sdata,
1183 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1184 
1185 	return 0;
1186 }
1187 
1188 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
1189 			const u8 *peer, u8 action_code, u8 dialog_token,
1190 			u16 status_code, u32 peer_capability,
1191 			bool initiator, const u8 *extra_ies,
1192 			size_t extra_ies_len)
1193 {
1194 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1195 	int ret;
1196 
1197 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1198 		return -ENOTSUPP;
1199 
1200 	/* make sure we are in managed mode, and associated */
1201 	if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1202 	    !sdata->u.mgd.associated)
1203 		return -EINVAL;
1204 
1205 	switch (action_code) {
1206 	case WLAN_TDLS_SETUP_REQUEST:
1207 	case WLAN_TDLS_SETUP_RESPONSE:
1208 		ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1209 						dialog_token, status_code,
1210 						peer_capability, initiator,
1211 						extra_ies, extra_ies_len);
1212 		break;
1213 	case WLAN_TDLS_TEARDOWN:
1214 		ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1215 						   action_code, dialog_token,
1216 						   status_code,
1217 						   peer_capability, initiator,
1218 						   extra_ies, extra_ies_len);
1219 		break;
1220 	case WLAN_TDLS_DISCOVERY_REQUEST:
1221 		/*
1222 		 * Protect the discovery so we can hear the TDLS discovery
1223 		 * response frame. It is transmitted directly and not buffered
1224 		 * by the AP.
1225 		 */
1226 		drv_mgd_protect_tdls_discover(sdata->local, sdata);
1227 		/* fall-through */
1228 	case WLAN_TDLS_SETUP_CONFIRM:
1229 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1230 		/* no special handling */
1231 		ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1232 						      action_code,
1233 						      dialog_token,
1234 						      status_code,
1235 						      peer_capability,
1236 						      initiator, extra_ies,
1237 						      extra_ies_len, 0, NULL);
1238 		break;
1239 	default:
1240 		ret = -EOPNOTSUPP;
1241 		break;
1242 	}
1243 
1244 	tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1245 		 action_code, peer, ret);
1246 	return ret;
1247 }
1248 
1249 static void iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data *sdata,
1250 					 struct sta_info *sta)
1251 {
1252 	struct ieee80211_local *local = sdata->local;
1253 	struct ieee80211_chanctx_conf *conf;
1254 	struct ieee80211_chanctx *ctx;
1255 	enum nl80211_chan_width width;
1256 	struct ieee80211_supported_band *sband;
1257 
1258 	mutex_lock(&local->chanctx_mtx);
1259 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1260 					 lockdep_is_held(&local->chanctx_mtx));
1261 	if (conf) {
1262 		width = conf->def.width;
1263 		sband = local->hw.wiphy->bands[conf->def.chan->band];
1264 		ctx = container_of(conf, struct ieee80211_chanctx, conf);
1265 		ieee80211_recalc_chanctx_chantype(local, ctx);
1266 
1267 		/* if width changed and a peer is given, update its BW */
1268 		if (width != conf->def.width && sta &&
1269 		    test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW)) {
1270 			enum ieee80211_sta_rx_bandwidth bw;
1271 
1272 			bw = ieee80211_chan_width_to_rx_bw(conf->def.width);
1273 			bw = min(bw, ieee80211_sta_cap_rx_bw(sta));
1274 			if (bw != sta->sta.bandwidth) {
1275 				sta->sta.bandwidth = bw;
1276 				rate_control_rate_update(local, sband, sta,
1277 							 IEEE80211_RC_BW_CHANGED);
1278 				/*
1279 				 * if a TDLS peer BW was updated, we need to
1280 				 * recalc the chandef width again, to get the
1281 				 * correct chanctx min_def
1282 				 */
1283 				ieee80211_recalc_chanctx_chantype(local, ctx);
1284 			}
1285 		}
1286 
1287 	}
1288 	mutex_unlock(&local->chanctx_mtx);
1289 }
1290 
1291 static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
1292 {
1293 	struct sta_info *sta;
1294 	bool result = false;
1295 
1296 	rcu_read_lock();
1297 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1298 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1299 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
1300 		    !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
1301 		    !sta->sta.ht_cap.ht_supported)
1302 			continue;
1303 		result = true;
1304 		break;
1305 	}
1306 	rcu_read_unlock();
1307 
1308 	return result;
1309 }
1310 
1311 static void
1312 iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
1313 				   struct sta_info *sta)
1314 {
1315 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
1316 	bool tdls_ht;
1317 	u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
1318 			 IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
1319 			 IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
1320 	u16 opmode;
1321 
1322 	/* Nothing to do if the BSS connection uses HT */
1323 	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
1324 		return;
1325 
1326 	tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
1327 		  iee80211_tdls_have_ht_peers(sdata);
1328 
1329 	opmode = sdata->vif.bss_conf.ht_operation_mode;
1330 
1331 	if (tdls_ht)
1332 		opmode |= protection;
1333 	else
1334 		opmode &= ~protection;
1335 
1336 	if (opmode == sdata->vif.bss_conf.ht_operation_mode)
1337 		return;
1338 
1339 	sdata->vif.bss_conf.ht_operation_mode = opmode;
1340 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
1341 }
1342 
1343 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1344 			const u8 *peer, enum nl80211_tdls_operation oper)
1345 {
1346 	struct sta_info *sta;
1347 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1348 	struct ieee80211_local *local = sdata->local;
1349 	int ret;
1350 
1351 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1352 		return -ENOTSUPP;
1353 
1354 	if (sdata->vif.type != NL80211_IFTYPE_STATION)
1355 		return -EINVAL;
1356 
1357 	switch (oper) {
1358 	case NL80211_TDLS_ENABLE_LINK:
1359 	case NL80211_TDLS_DISABLE_LINK:
1360 		break;
1361 	case NL80211_TDLS_TEARDOWN:
1362 	case NL80211_TDLS_SETUP:
1363 	case NL80211_TDLS_DISCOVERY_REQ:
1364 		/* We don't support in-driver setup/teardown/discovery */
1365 		return -ENOTSUPP;
1366 	}
1367 
1368 	/* protect possible bss_conf changes and avoid concurrency in
1369 	 * ieee80211_bss_info_change_notify()
1370 	 */
1371 	sdata_lock(sdata);
1372 	mutex_lock(&local->mtx);
1373 	tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1374 
1375 	switch (oper) {
1376 	case NL80211_TDLS_ENABLE_LINK:
1377 		if (sdata->vif.csa_active) {
1378 			tdls_dbg(sdata, "TDLS: disallow link during CSA\n");
1379 			ret = -EBUSY;
1380 			break;
1381 		}
1382 
1383 		mutex_lock(&local->sta_mtx);
1384 		sta = sta_info_get(sdata, peer);
1385 		if (!sta) {
1386 			mutex_unlock(&local->sta_mtx);
1387 			ret = -ENOLINK;
1388 			break;
1389 		}
1390 
1391 		iee80211_tdls_recalc_chanctx(sdata, sta);
1392 		iee80211_tdls_recalc_ht_protection(sdata, sta);
1393 
1394 		set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1395 		mutex_unlock(&local->sta_mtx);
1396 
1397 		WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1398 			     !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1399 		ret = 0;
1400 		break;
1401 	case NL80211_TDLS_DISABLE_LINK:
1402 		/*
1403 		 * The teardown message in ieee80211_tdls_mgmt_teardown() was
1404 		 * created while the queues were stopped, so it might still be
1405 		 * pending. Before flushing the queues we need to be sure the
1406 		 * message is handled by the tasklet handling pending messages,
1407 		 * otherwise we might start destroying the station before
1408 		 * sending the teardown packet.
1409 		 * Note that this only forces the tasklet to flush pendings -
1410 		 * not to stop the tasklet from rescheduling itself.
1411 		 */
1412 		tasklet_kill(&local->tx_pending_tasklet);
1413 		/* flush a potentially queued teardown packet */
1414 		ieee80211_flush_queues(local, sdata, false);
1415 
1416 		ret = sta_info_destroy_addr(sdata, peer);
1417 
1418 		mutex_lock(&local->sta_mtx);
1419 		iee80211_tdls_recalc_ht_protection(sdata, NULL);
1420 		mutex_unlock(&local->sta_mtx);
1421 
1422 		iee80211_tdls_recalc_chanctx(sdata, NULL);
1423 		break;
1424 	default:
1425 		ret = -ENOTSUPP;
1426 		break;
1427 	}
1428 
1429 	if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1430 		cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1431 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1432 	}
1433 
1434 	if (ret == 0)
1435 		ieee80211_queue_work(&sdata->local->hw,
1436 				     &sdata->u.mgd.request_smps_work);
1437 
1438 	mutex_unlock(&local->mtx);
1439 	sdata_unlock(sdata);
1440 	return ret;
1441 }
1442 
1443 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1444 				 enum nl80211_tdls_operation oper,
1445 				 u16 reason_code, gfp_t gfp)
1446 {
1447 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1448 
1449 	if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1450 		sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1451 			  oper);
1452 		return;
1453 	}
1454 
1455 	cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1456 }
1457 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1458 
1459 static void
1460 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1461 {
1462 	struct ieee80211_ch_switch_timing *ch_sw;
1463 
1464 	*buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1465 	*buf++ = sizeof(struct ieee80211_ch_switch_timing);
1466 
1467 	ch_sw = (void *)buf;
1468 	ch_sw->switch_time = cpu_to_le16(switch_time);
1469 	ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1470 }
1471 
1472 /* find switch timing IE in SKB ready for Tx */
1473 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1474 {
1475 	struct ieee80211_tdls_data *tf;
1476 	const u8 *ie_start;
1477 
1478 	/*
1479 	 * Get the offset for the new location of the switch timing IE.
1480 	 * The SKB network header will now point to the "payload_type"
1481 	 * element of the TDLS data frame struct.
1482 	 */
1483 	tf = container_of(skb->data + skb_network_offset(skb),
1484 			  struct ieee80211_tdls_data, payload_type);
1485 	ie_start = tf->u.chan_switch_req.variable;
1486 	return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1487 				skb->len - (ie_start - skb->data));
1488 }
1489 
1490 static struct sk_buff *
1491 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1492 			      struct cfg80211_chan_def *chandef,
1493 			      u32 *ch_sw_tm_ie_offset)
1494 {
1495 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1496 	u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1497 		     2 + sizeof(struct ieee80211_ch_switch_timing)];
1498 	int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1499 	u8 *pos = extra_ies;
1500 	struct sk_buff *skb;
1501 
1502 	/*
1503 	 * if chandef points to a wide channel add a Secondary-Channel
1504 	 * Offset information element
1505 	 */
1506 	if (chandef->width == NL80211_CHAN_WIDTH_40) {
1507 		struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1508 		bool ht40plus;
1509 
1510 		*pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1511 		*pos++ = sizeof(*sec_chan_ie);
1512 		sec_chan_ie = (void *)pos;
1513 
1514 		ht40plus = cfg80211_get_chandef_type(chandef) ==
1515 							NL80211_CHAN_HT40PLUS;
1516 		sec_chan_ie->sec_chan_offs = ht40plus ?
1517 					     IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1518 					     IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1519 		pos += sizeof(*sec_chan_ie);
1520 
1521 		extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1522 	}
1523 
1524 	/* just set the values to 0, this is a template */
1525 	iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1526 
1527 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1528 					      WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1529 					      0, 0, !sta->sta.tdls_initiator,
1530 					      extra_ies, extra_ies_len,
1531 					      oper_class, chandef);
1532 	if (!skb)
1533 		return NULL;
1534 
1535 	skb = ieee80211_build_data_template(sdata, skb, 0);
1536 	if (IS_ERR(skb)) {
1537 		tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1538 		return NULL;
1539 	}
1540 
1541 	if (ch_sw_tm_ie_offset) {
1542 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1543 
1544 		if (!tm_ie) {
1545 			tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1546 			dev_kfree_skb_any(skb);
1547 			return NULL;
1548 		}
1549 
1550 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1551 	}
1552 
1553 	tdls_dbg(sdata,
1554 		 "TDLS channel switch request template for %pM ch %d width %d\n",
1555 		 sta->sta.addr, chandef->chan->center_freq, chandef->width);
1556 	return skb;
1557 }
1558 
1559 int
1560 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1561 			      const u8 *addr, u8 oper_class,
1562 			      struct cfg80211_chan_def *chandef)
1563 {
1564 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1565 	struct ieee80211_local *local = sdata->local;
1566 	struct sta_info *sta;
1567 	struct sk_buff *skb = NULL;
1568 	u32 ch_sw_tm_ie;
1569 	int ret;
1570 
1571 	mutex_lock(&local->sta_mtx);
1572 	sta = sta_info_get(sdata, addr);
1573 	if (!sta) {
1574 		tdls_dbg(sdata,
1575 			 "Invalid TDLS peer %pM for channel switch request\n",
1576 			 addr);
1577 		ret = -ENOENT;
1578 		goto out;
1579 	}
1580 
1581 	if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1582 		tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1583 			 addr);
1584 		ret = -ENOTSUPP;
1585 		goto out;
1586 	}
1587 
1588 	skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1589 					    &ch_sw_tm_ie);
1590 	if (!skb) {
1591 		ret = -ENOENT;
1592 		goto out;
1593 	}
1594 
1595 	ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1596 				      chandef, skb, ch_sw_tm_ie);
1597 	if (!ret)
1598 		set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1599 
1600 out:
1601 	mutex_unlock(&local->sta_mtx);
1602 	dev_kfree_skb_any(skb);
1603 	return ret;
1604 }
1605 
1606 void
1607 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1608 				     struct net_device *dev,
1609 				     const u8 *addr)
1610 {
1611 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1612 	struct ieee80211_local *local = sdata->local;
1613 	struct sta_info *sta;
1614 
1615 	mutex_lock(&local->sta_mtx);
1616 	sta = sta_info_get(sdata, addr);
1617 	if (!sta) {
1618 		tdls_dbg(sdata,
1619 			 "Invalid TDLS peer %pM for channel switch cancel\n",
1620 			 addr);
1621 		goto out;
1622 	}
1623 
1624 	if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1625 		tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1626 			 addr);
1627 		goto out;
1628 	}
1629 
1630 	drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1631 	clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1632 
1633 out:
1634 	mutex_unlock(&local->sta_mtx);
1635 }
1636 
1637 static struct sk_buff *
1638 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1639 				   u32 *ch_sw_tm_ie_offset)
1640 {
1641 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1642 	struct sk_buff *skb;
1643 	u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1644 
1645 	/* initial timing are always zero in the template */
1646 	iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1647 
1648 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1649 					WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1650 					0, 0, !sta->sta.tdls_initiator,
1651 					extra_ies, sizeof(extra_ies), 0, NULL);
1652 	if (!skb)
1653 		return NULL;
1654 
1655 	skb = ieee80211_build_data_template(sdata, skb, 0);
1656 	if (IS_ERR(skb)) {
1657 		tdls_dbg(sdata,
1658 			 "Failed building TDLS channel switch resp frame\n");
1659 		return NULL;
1660 	}
1661 
1662 	if (ch_sw_tm_ie_offset) {
1663 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1664 
1665 		if (!tm_ie) {
1666 			tdls_dbg(sdata,
1667 				 "No switch timing IE in TDLS switch resp\n");
1668 			dev_kfree_skb_any(skb);
1669 			return NULL;
1670 		}
1671 
1672 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1673 	}
1674 
1675 	tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1676 		 sta->sta.addr);
1677 	return skb;
1678 }
1679 
1680 static int
1681 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1682 					   struct sk_buff *skb)
1683 {
1684 	struct ieee80211_local *local = sdata->local;
1685 	struct ieee802_11_elems elems;
1686 	struct sta_info *sta;
1687 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1688 	bool local_initiator;
1689 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1690 	int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1691 	struct ieee80211_tdls_ch_sw_params params = {};
1692 	int ret;
1693 
1694 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1695 	params.timestamp = rx_status->device_timestamp;
1696 
1697 	if (skb->len < baselen) {
1698 		tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1699 			 skb->len);
1700 		return -EINVAL;
1701 	}
1702 
1703 	mutex_lock(&local->sta_mtx);
1704 	sta = sta_info_get(sdata, tf->sa);
1705 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1706 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1707 			 tf->sa);
1708 		ret = -EINVAL;
1709 		goto out;
1710 	}
1711 
1712 	params.sta = &sta->sta;
1713 	params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1714 	if (params.status != 0) {
1715 		ret = 0;
1716 		goto call_drv;
1717 	}
1718 
1719 	ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1720 			       skb->len - baselen, false, &elems,
1721 			       NULL, NULL);
1722 	if (elems.parse_error) {
1723 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1724 		ret = -EINVAL;
1725 		goto out;
1726 	}
1727 
1728 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1729 		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1730 		ret = -EINVAL;
1731 		goto out;
1732 	}
1733 
1734 	/* validate the initiator is set correctly */
1735 	local_initiator =
1736 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1737 	if (local_initiator == sta->sta.tdls_initiator) {
1738 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1739 		ret = -EINVAL;
1740 		goto out;
1741 	}
1742 
1743 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1744 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1745 
1746 	params.tmpl_skb =
1747 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1748 	if (!params.tmpl_skb) {
1749 		ret = -ENOENT;
1750 		goto out;
1751 	}
1752 
1753 	ret = 0;
1754 call_drv:
1755 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1756 
1757 	tdls_dbg(sdata,
1758 		 "TDLS channel switch response received from %pM status %d\n",
1759 		 tf->sa, params.status);
1760 
1761 out:
1762 	mutex_unlock(&local->sta_mtx);
1763 	dev_kfree_skb_any(params.tmpl_skb);
1764 	return ret;
1765 }
1766 
1767 static int
1768 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1769 					  struct sk_buff *skb)
1770 {
1771 	struct ieee80211_local *local = sdata->local;
1772 	struct ieee802_11_elems elems;
1773 	struct cfg80211_chan_def chandef;
1774 	struct ieee80211_channel *chan;
1775 	enum nl80211_channel_type chan_type;
1776 	int freq;
1777 	u8 target_channel, oper_class;
1778 	bool local_initiator;
1779 	struct sta_info *sta;
1780 	enum nl80211_band band;
1781 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1782 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1783 	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1784 	struct ieee80211_tdls_ch_sw_params params = {};
1785 	int ret = 0;
1786 
1787 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1788 	params.timestamp = rx_status->device_timestamp;
1789 
1790 	if (skb->len < baselen) {
1791 		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1792 			 skb->len);
1793 		return -EINVAL;
1794 	}
1795 
1796 	target_channel = tf->u.chan_switch_req.target_channel;
1797 	oper_class = tf->u.chan_switch_req.oper_class;
1798 
1799 	/*
1800 	 * We can't easily infer the channel band. The operating class is
1801 	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1802 	 * solution here is to treat channels with number >14 as 5GHz ones,
1803 	 * and specifically check for the (oper_class, channel) combinations
1804 	 * where this doesn't hold. These are thankfully unique according to
1805 	 * IEEE802.11-2012.
1806 	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1807 	 * valid here.
1808 	 */
1809 	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1810 	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1811 	     target_channel < 14)
1812 		band = NL80211_BAND_5GHZ;
1813 	else
1814 		band = target_channel < 14 ? NL80211_BAND_2GHZ :
1815 					     NL80211_BAND_5GHZ;
1816 
1817 	freq = ieee80211_channel_to_frequency(target_channel, band);
1818 	if (freq == 0) {
1819 		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1820 			 target_channel);
1821 		return -EINVAL;
1822 	}
1823 
1824 	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1825 	if (!chan) {
1826 		tdls_dbg(sdata,
1827 			 "Unsupported channel for TDLS chan switch: %d\n",
1828 			 target_channel);
1829 		return -EINVAL;
1830 	}
1831 
1832 	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1833 			       skb->len - baselen, false, &elems, NULL, NULL);
1834 	if (elems.parse_error) {
1835 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1836 		return -EINVAL;
1837 	}
1838 
1839 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1840 		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1841 		return -EINVAL;
1842 	}
1843 
1844 	if (!elems.sec_chan_offs) {
1845 		chan_type = NL80211_CHAN_HT20;
1846 	} else {
1847 		switch (elems.sec_chan_offs->sec_chan_offs) {
1848 		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1849 			chan_type = NL80211_CHAN_HT40PLUS;
1850 			break;
1851 		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1852 			chan_type = NL80211_CHAN_HT40MINUS;
1853 			break;
1854 		default:
1855 			chan_type = NL80211_CHAN_HT20;
1856 			break;
1857 		}
1858 	}
1859 
1860 	cfg80211_chandef_create(&chandef, chan, chan_type);
1861 
1862 	/* we will be active on the TDLS link */
1863 	if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1864 					   sdata->wdev.iftype)) {
1865 		tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1866 		return -EINVAL;
1867 	}
1868 
1869 	mutex_lock(&local->sta_mtx);
1870 	sta = sta_info_get(sdata, tf->sa);
1871 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1872 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1873 			 tf->sa);
1874 		ret = -EINVAL;
1875 		goto out;
1876 	}
1877 
1878 	params.sta = &sta->sta;
1879 
1880 	/* validate the initiator is set correctly */
1881 	local_initiator =
1882 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1883 	if (local_initiator == sta->sta.tdls_initiator) {
1884 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1885 		ret = -EINVAL;
1886 		goto out;
1887 	}
1888 
1889 	/* peer should have known better */
1890 	if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1891 	    elems.sec_chan_offs->sec_chan_offs) {
1892 		tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1893 		ret = -ENOTSUPP;
1894 		goto out;
1895 	}
1896 
1897 	params.chandef = &chandef;
1898 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1899 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1900 
1901 	params.tmpl_skb =
1902 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1903 						   &params.ch_sw_tm_ie);
1904 	if (!params.tmpl_skb) {
1905 		ret = -ENOENT;
1906 		goto out;
1907 	}
1908 
1909 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1910 
1911 	tdls_dbg(sdata,
1912 		 "TDLS ch switch request received from %pM ch %d width %d\n",
1913 		 tf->sa, params.chandef->chan->center_freq,
1914 		 params.chandef->width);
1915 out:
1916 	mutex_unlock(&local->sta_mtx);
1917 	dev_kfree_skb_any(params.tmpl_skb);
1918 	return ret;
1919 }
1920 
1921 static void
1922 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1923 				      struct sk_buff *skb)
1924 {
1925 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1926 	struct wiphy *wiphy = sdata->local->hw.wiphy;
1927 
1928 	ASSERT_RTNL();
1929 
1930 	/* make sure the driver supports it */
1931 	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1932 		return;
1933 
1934 	/* we want to access the entire packet */
1935 	if (skb_linearize(skb))
1936 		return;
1937 	/*
1938 	 * The packet/size was already validated by mac80211 Rx path, only look
1939 	 * at the action type.
1940 	 */
1941 	switch (tf->action_code) {
1942 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1943 		ieee80211_process_tdls_channel_switch_req(sdata, skb);
1944 		break;
1945 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1946 		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1947 		break;
1948 	default:
1949 		WARN_ON_ONCE(1);
1950 		return;
1951 	}
1952 }
1953 
1954 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1955 {
1956 	struct sta_info *sta;
1957 	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1958 
1959 	rcu_read_lock();
1960 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1961 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1962 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1963 			continue;
1964 
1965 		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1966 					    NL80211_TDLS_TEARDOWN, reason,
1967 					    GFP_ATOMIC);
1968 	}
1969 	rcu_read_unlock();
1970 }
1971 
1972 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1973 {
1974 	struct ieee80211_local *local =
1975 		container_of(wk, struct ieee80211_local, tdls_chsw_work);
1976 	struct ieee80211_sub_if_data *sdata;
1977 	struct sk_buff *skb;
1978 	struct ieee80211_tdls_data *tf;
1979 
1980 	rtnl_lock();
1981 	while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1982 		tf = (struct ieee80211_tdls_data *)skb->data;
1983 		list_for_each_entry(sdata, &local->interfaces, list) {
1984 			if (!ieee80211_sdata_running(sdata) ||
1985 			    sdata->vif.type != NL80211_IFTYPE_STATION ||
1986 			    !ether_addr_equal(tf->da, sdata->vif.addr))
1987 				continue;
1988 
1989 			ieee80211_process_tdls_channel_switch(sdata, skb);
1990 			break;
1991 		}
1992 
1993 		kfree_skb(skb);
1994 	}
1995 	rtnl_unlock();
1996 }
1997