xref: /openbmc/linux/net/mac80211/tdls.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * mac80211 TDLS handling code
4  *
5  * Copyright 2006-2010	Johannes Berg <johannes@sipsolutions.net>
6  * Copyright 2014, Intel Corporation
7  * Copyright 2014  Intel Mobile Communications GmbH
8  * Copyright 2015 - 2016 Intel Deutschland GmbH
9  * Copyright (C) 2019 Intel Corporation
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 #include "wme.h"
20 
21 /* give usermode some time for retries in setting up the TDLS session */
22 #define TDLS_PEER_SETUP_TIMEOUT	(15 * HZ)
23 
24 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
25 {
26 	struct ieee80211_sub_if_data *sdata;
27 	struct ieee80211_local *local;
28 
29 	sdata = container_of(wk, struct ieee80211_sub_if_data,
30 			     u.mgd.tdls_peer_del_work.work);
31 	local = sdata->local;
32 
33 	mutex_lock(&local->mtx);
34 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
35 		tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
36 		sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
37 		eth_zero_addr(sdata->u.mgd.tdls_peer);
38 	}
39 	mutex_unlock(&local->mtx);
40 }
41 
42 static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
43 					 struct sk_buff *skb)
44 {
45 	struct ieee80211_local *local = sdata->local;
46 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
47 	bool chan_switch = local->hw.wiphy->features &
48 			   NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
49 	bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW) &&
50 			  !ifmgd->tdls_wider_bw_prohibited;
51 	bool buffer_sta = ieee80211_hw_check(&local->hw,
52 					     SUPPORTS_TDLS_BUFFER_STA);
53 	struct ieee80211_supported_band *sband = ieee80211_get_sband(sdata);
54 	bool vht = sband && sband->vht_cap.vht_supported;
55 	u8 *pos = skb_put(skb, 10);
56 
57 	*pos++ = WLAN_EID_EXT_CAPABILITY;
58 	*pos++ = 8; /* len */
59 	*pos++ = 0x0;
60 	*pos++ = 0x0;
61 	*pos++ = 0x0;
62 	*pos++ = (chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0) |
63 		 (buffer_sta ? WLAN_EXT_CAPA4_TDLS_BUFFER_STA : 0);
64 	*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
65 	*pos++ = 0;
66 	*pos++ = 0;
67 	*pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
68 }
69 
70 static u8
71 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
72 			   struct sk_buff *skb, u16 start, u16 end,
73 			   u16 spacing)
74 {
75 	u8 subband_cnt = 0, ch_cnt = 0;
76 	struct ieee80211_channel *ch;
77 	struct cfg80211_chan_def chandef;
78 	int i, subband_start;
79 	struct wiphy *wiphy = sdata->local->hw.wiphy;
80 
81 	for (i = start; i <= end; i += spacing) {
82 		if (!ch_cnt)
83 			subband_start = i;
84 
85 		ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
86 		if (ch) {
87 			/* we will be active on the channel */
88 			cfg80211_chandef_create(&chandef, ch,
89 						NL80211_CHAN_NO_HT);
90 			if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
91 							  sdata->wdev.iftype)) {
92 				ch_cnt++;
93 				/*
94 				 * check if the next channel is also part of
95 				 * this allowed range
96 				 */
97 				continue;
98 			}
99 		}
100 
101 		/*
102 		 * we've reached the end of a range, with allowed channels
103 		 * found
104 		 */
105 		if (ch_cnt) {
106 			u8 *pos = skb_put(skb, 2);
107 			*pos++ = ieee80211_frequency_to_channel(subband_start);
108 			*pos++ = ch_cnt;
109 
110 			subband_cnt++;
111 			ch_cnt = 0;
112 		}
113 	}
114 
115 	/* all channels in the requested range are allowed - add them here */
116 	if (ch_cnt) {
117 		u8 *pos = skb_put(skb, 2);
118 		*pos++ = ieee80211_frequency_to_channel(subband_start);
119 		*pos++ = ch_cnt;
120 
121 		subband_cnt++;
122 	}
123 
124 	return subband_cnt;
125 }
126 
127 static void
128 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
129 				 struct sk_buff *skb)
130 {
131 	/*
132 	 * Add possible channels for TDLS. These are channels that are allowed
133 	 * to be active.
134 	 */
135 	u8 subband_cnt;
136 	u8 *pos = skb_put(skb, 2);
137 
138 	*pos++ = WLAN_EID_SUPPORTED_CHANNELS;
139 
140 	/*
141 	 * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
142 	 * this doesn't happen in real world scenarios.
143 	 */
144 
145 	/* 2GHz, with 5MHz spacing */
146 	subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
147 
148 	/* 5GHz, with 20MHz spacing */
149 	subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
150 
151 	/* length */
152 	*pos = 2 * subband_cnt;
153 }
154 
155 static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
156 					    struct sk_buff *skb)
157 {
158 	u8 *pos;
159 	u8 op_class;
160 
161 	if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
162 						  &op_class))
163 		return;
164 
165 	pos = skb_put(skb, 4);
166 	*pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
167 	*pos++ = 2; /* len */
168 
169 	*pos++ = op_class;
170 	*pos++ = op_class; /* give current operating class as alternate too */
171 }
172 
173 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
174 {
175 	u8 *pos = skb_put(skb, 3);
176 
177 	*pos++ = WLAN_EID_BSS_COEX_2040;
178 	*pos++ = 1; /* len */
179 
180 	*pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
181 }
182 
183 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
184 					u16 status_code)
185 {
186 	struct ieee80211_supported_band *sband;
187 
188 	/* The capability will be 0 when sending a failure code */
189 	if (status_code != 0)
190 		return 0;
191 
192 	sband = ieee80211_get_sband(sdata);
193 	if (sband && sband->band == NL80211_BAND_2GHZ) {
194 		return WLAN_CAPABILITY_SHORT_SLOT_TIME |
195 		       WLAN_CAPABILITY_SHORT_PREAMBLE;
196 	}
197 
198 	return 0;
199 }
200 
201 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
202 				       struct sk_buff *skb, const u8 *peer,
203 				       bool initiator)
204 {
205 	struct ieee80211_tdls_lnkie *lnkid;
206 	const u8 *init_addr, *rsp_addr;
207 
208 	if (initiator) {
209 		init_addr = sdata->vif.addr;
210 		rsp_addr = peer;
211 	} else {
212 		init_addr = peer;
213 		rsp_addr = sdata->vif.addr;
214 	}
215 
216 	lnkid = skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
217 
218 	lnkid->ie_type = WLAN_EID_LINK_ID;
219 	lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
220 
221 	memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
222 	memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
223 	memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
224 }
225 
226 static void
227 ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
228 {
229 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
230 	u8 *pos = skb_put(skb, 4);
231 
232 	*pos++ = WLAN_EID_AID;
233 	*pos++ = 2; /* len */
234 	put_unaligned_le16(ifmgd->aid, pos);
235 }
236 
237 /* translate numbering in the WMM parameter IE to the mac80211 notation */
238 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
239 {
240 	switch (ac) {
241 	default:
242 		WARN_ON_ONCE(1);
243 		/* fall through */
244 	case 0:
245 		return IEEE80211_AC_BE;
246 	case 1:
247 		return IEEE80211_AC_BK;
248 	case 2:
249 		return IEEE80211_AC_VI;
250 	case 3:
251 		return IEEE80211_AC_VO;
252 	}
253 }
254 
255 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
256 {
257 	u8 ret;
258 
259 	ret = aifsn & 0x0f;
260 	if (acm)
261 		ret |= 0x10;
262 	ret |= (aci << 5) & 0x60;
263 	return ret;
264 }
265 
266 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
267 {
268 	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
269 	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
270 }
271 
272 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
273 					    struct sk_buff *skb)
274 {
275 	struct ieee80211_wmm_param_ie *wmm;
276 	struct ieee80211_tx_queue_params *txq;
277 	int i;
278 
279 	wmm = skb_put_zero(skb, sizeof(*wmm));
280 
281 	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
282 	wmm->len = sizeof(*wmm) - 2;
283 
284 	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
285 	wmm->oui[1] = 0x50;
286 	wmm->oui[2] = 0xf2;
287 	wmm->oui_type = 2; /* WME */
288 	wmm->oui_subtype = 1; /* WME param */
289 	wmm->version = 1; /* WME ver */
290 	wmm->qos_info = 0; /* U-APSD not in use */
291 
292 	/*
293 	 * Use the EDCA parameters defined for the BSS, or default if the AP
294 	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
295 	 */
296 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
297 		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
298 		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
299 							       txq->acm, i);
300 		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
301 		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
302 	}
303 }
304 
305 static void
306 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
307 				   struct sta_info *sta)
308 {
309 	/* IEEE802.11ac-2013 Table E-4 */
310 	u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
311 	struct cfg80211_chan_def uc = sta->tdls_chandef;
312 	enum nl80211_chan_width max_width = ieee80211_sta_cap_chan_bw(sta);
313 	int i;
314 
315 	/* only support upgrading non-narrow channels up to 80Mhz */
316 	if (max_width == NL80211_CHAN_WIDTH_5 ||
317 	    max_width == NL80211_CHAN_WIDTH_10)
318 		return;
319 
320 	if (max_width > NL80211_CHAN_WIDTH_80)
321 		max_width = NL80211_CHAN_WIDTH_80;
322 
323 	if (uc.width >= max_width)
324 		return;
325 	/*
326 	 * Channel usage constrains in the IEEE802.11ac-2013 specification only
327 	 * allow expanding a 20MHz channel to 80MHz in a single way. In
328 	 * addition, there are no 40MHz allowed channels that are not part of
329 	 * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
330 	 */
331 	for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
332 		if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
333 			uc.center_freq1 = centers_80mhz[i];
334 			uc.center_freq2 = 0;
335 			uc.width = NL80211_CHAN_WIDTH_80;
336 			break;
337 		}
338 
339 	if (!uc.center_freq1)
340 		return;
341 
342 	/* proceed to downgrade the chandef until usable or the same as AP BW */
343 	while (uc.width > max_width ||
344 	       (uc.width > sta->tdls_chandef.width &&
345 		!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &uc,
346 					       sdata->wdev.iftype)))
347 		ieee80211_chandef_downgrade(&uc);
348 
349 	if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
350 		tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
351 			 sta->tdls_chandef.width, uc.width);
352 
353 		/*
354 		 * the station is not yet authorized when BW upgrade is done,
355 		 * locking is not required
356 		 */
357 		sta->tdls_chandef = uc;
358 	}
359 }
360 
361 static void
362 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
363 				   struct sk_buff *skb, const u8 *peer,
364 				   u8 action_code, bool initiator,
365 				   const u8 *extra_ies, size_t extra_ies_len)
366 {
367 	struct ieee80211_supported_band *sband;
368 	struct ieee80211_local *local = sdata->local;
369 	struct ieee80211_sta_ht_cap ht_cap;
370 	struct ieee80211_sta_vht_cap vht_cap;
371 	struct sta_info *sta = NULL;
372 	size_t offset = 0, noffset;
373 	u8 *pos;
374 
375 	sband = ieee80211_get_sband(sdata);
376 	if (!sband)
377 		return;
378 
379 	ieee80211_add_srates_ie(sdata, skb, false, sband->band);
380 	ieee80211_add_ext_srates_ie(sdata, skb, false, sband->band);
381 	ieee80211_tdls_add_supp_channels(sdata, skb);
382 
383 	/* add any custom IEs that go before Extended Capabilities */
384 	if (extra_ies_len) {
385 		static const u8 before_ext_cap[] = {
386 			WLAN_EID_SUPP_RATES,
387 			WLAN_EID_COUNTRY,
388 			WLAN_EID_EXT_SUPP_RATES,
389 			WLAN_EID_SUPPORTED_CHANNELS,
390 			WLAN_EID_RSN,
391 		};
392 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
393 					     before_ext_cap,
394 					     ARRAY_SIZE(before_ext_cap),
395 					     offset);
396 		skb_put_data(skb, extra_ies + offset, noffset - offset);
397 		offset = noffset;
398 	}
399 
400 	ieee80211_tdls_add_ext_capab(sdata, skb);
401 
402 	/* add the QoS element if we support it */
403 	if (local->hw.queues >= IEEE80211_NUM_ACS &&
404 	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
405 		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
406 
407 	/* add any custom IEs that go before HT capabilities */
408 	if (extra_ies_len) {
409 		static const u8 before_ht_cap[] = {
410 			WLAN_EID_SUPP_RATES,
411 			WLAN_EID_COUNTRY,
412 			WLAN_EID_EXT_SUPP_RATES,
413 			WLAN_EID_SUPPORTED_CHANNELS,
414 			WLAN_EID_RSN,
415 			WLAN_EID_EXT_CAPABILITY,
416 			WLAN_EID_QOS_CAPA,
417 			WLAN_EID_FAST_BSS_TRANSITION,
418 			WLAN_EID_TIMEOUT_INTERVAL,
419 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
420 		};
421 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
422 					     before_ht_cap,
423 					     ARRAY_SIZE(before_ht_cap),
424 					     offset);
425 		skb_put_data(skb, extra_ies + offset, noffset - offset);
426 		offset = noffset;
427 	}
428 
429 	mutex_lock(&local->sta_mtx);
430 
431 	/* we should have the peer STA if we're already responding */
432 	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
433 		sta = sta_info_get(sdata, peer);
434 		if (WARN_ON_ONCE(!sta)) {
435 			mutex_unlock(&local->sta_mtx);
436 			return;
437 		}
438 
439 		sta->tdls_chandef = sdata->vif.bss_conf.chandef;
440 	}
441 
442 	ieee80211_tdls_add_oper_classes(sdata, skb);
443 
444 	/*
445 	 * with TDLS we can switch channels, and HT-caps are not necessarily
446 	 * the same on all bands. The specification limits the setup to a
447 	 * single HT-cap, so use the current band for now.
448 	 */
449 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
450 
451 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
452 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
453 	    ht_cap.ht_supported) {
454 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
455 
456 		/* disable SMPS in TDLS initiator */
457 		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
458 				<< IEEE80211_HT_CAP_SM_PS_SHIFT;
459 
460 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
461 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
462 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
463 		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
464 		/* the peer caps are already intersected with our own */
465 		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
466 
467 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
468 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
469 	}
470 
471 	if (ht_cap.ht_supported &&
472 	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
473 		ieee80211_tdls_add_bss_coex_ie(skb);
474 
475 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
476 
477 	/* add any custom IEs that go before VHT capabilities */
478 	if (extra_ies_len) {
479 		static const u8 before_vht_cap[] = {
480 			WLAN_EID_SUPP_RATES,
481 			WLAN_EID_COUNTRY,
482 			WLAN_EID_EXT_SUPP_RATES,
483 			WLAN_EID_SUPPORTED_CHANNELS,
484 			WLAN_EID_RSN,
485 			WLAN_EID_EXT_CAPABILITY,
486 			WLAN_EID_QOS_CAPA,
487 			WLAN_EID_FAST_BSS_TRANSITION,
488 			WLAN_EID_TIMEOUT_INTERVAL,
489 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
490 			WLAN_EID_MULTI_BAND,
491 		};
492 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
493 					     before_vht_cap,
494 					     ARRAY_SIZE(before_vht_cap),
495 					     offset);
496 		skb_put_data(skb, extra_ies + offset, noffset - offset);
497 		offset = noffset;
498 	}
499 
500 	/* build the VHT-cap similarly to the HT-cap */
501 	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
502 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
503 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
504 	    vht_cap.vht_supported) {
505 		ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
506 
507 		/* the AID is present only when VHT is implemented */
508 		if (action_code == WLAN_TDLS_SETUP_REQUEST)
509 			ieee80211_tdls_add_aid(sdata, skb);
510 
511 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
512 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
513 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
514 		   vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
515 		/* the peer caps are already intersected with our own */
516 		memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
517 
518 		/* the AID is present only when VHT is implemented */
519 		ieee80211_tdls_add_aid(sdata, skb);
520 
521 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
522 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
523 
524 		/*
525 		 * if both peers support WIDER_BW, we can expand the chandef to
526 		 * a wider compatible one, up to 80MHz
527 		 */
528 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
529 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
530 	}
531 
532 	mutex_unlock(&local->sta_mtx);
533 
534 	/* add any remaining IEs */
535 	if (extra_ies_len) {
536 		noffset = extra_ies_len;
537 		skb_put_data(skb, extra_ies + offset, noffset - offset);
538 	}
539 
540 }
541 
542 static void
543 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
544 				 struct sk_buff *skb, const u8 *peer,
545 				 bool initiator, const u8 *extra_ies,
546 				 size_t extra_ies_len)
547 {
548 	struct ieee80211_local *local = sdata->local;
549 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
550 	size_t offset = 0, noffset;
551 	struct sta_info *sta, *ap_sta;
552 	struct ieee80211_supported_band *sband;
553 	u8 *pos;
554 
555 	sband = ieee80211_get_sband(sdata);
556 	if (!sband)
557 		return;
558 
559 	mutex_lock(&local->sta_mtx);
560 
561 	sta = sta_info_get(sdata, peer);
562 	ap_sta = sta_info_get(sdata, ifmgd->bssid);
563 	if (WARN_ON_ONCE(!sta || !ap_sta)) {
564 		mutex_unlock(&local->sta_mtx);
565 		return;
566 	}
567 
568 	sta->tdls_chandef = sdata->vif.bss_conf.chandef;
569 
570 	/* add any custom IEs that go before the QoS IE */
571 	if (extra_ies_len) {
572 		static const u8 before_qos[] = {
573 			WLAN_EID_RSN,
574 		};
575 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
576 					     before_qos,
577 					     ARRAY_SIZE(before_qos),
578 					     offset);
579 		skb_put_data(skb, extra_ies + offset, noffset - offset);
580 		offset = noffset;
581 	}
582 
583 	/* add the QoS param IE if both the peer and we support it */
584 	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
585 		ieee80211_tdls_add_wmm_param_ie(sdata, skb);
586 
587 	/* add any custom IEs that go before HT operation */
588 	if (extra_ies_len) {
589 		static const u8 before_ht_op[] = {
590 			WLAN_EID_RSN,
591 			WLAN_EID_QOS_CAPA,
592 			WLAN_EID_FAST_BSS_TRANSITION,
593 			WLAN_EID_TIMEOUT_INTERVAL,
594 		};
595 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
596 					     before_ht_op,
597 					     ARRAY_SIZE(before_ht_op),
598 					     offset);
599 		skb_put_data(skb, extra_ies + offset, noffset - offset);
600 		offset = noffset;
601 	}
602 
603 	/*
604 	 * if HT support is only added in TDLS, we need an HT-operation IE.
605 	 * add the IE as required by IEEE802.11-2012 9.23.3.2.
606 	 */
607 	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
608 		u16 prot = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
609 			   IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
610 			   IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
611 
612 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
613 		ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
614 					   &sdata->vif.bss_conf.chandef, prot,
615 					   true);
616 	}
617 
618 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
619 
620 	/* only include VHT-operation if not on the 2.4GHz band */
621 	if (sband->band != NL80211_BAND_2GHZ &&
622 	    sta->sta.vht_cap.vht_supported) {
623 		/*
624 		 * if both peers support WIDER_BW, we can expand the chandef to
625 		 * a wider compatible one, up to 80MHz
626 		 */
627 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
628 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
629 
630 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
631 		ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
632 					    &sta->tdls_chandef);
633 	}
634 
635 	mutex_unlock(&local->sta_mtx);
636 
637 	/* add any remaining IEs */
638 	if (extra_ies_len) {
639 		noffset = extra_ies_len;
640 		skb_put_data(skb, extra_ies + offset, noffset - offset);
641 	}
642 }
643 
644 static void
645 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
646 				       struct sk_buff *skb, const u8 *peer,
647 				       bool initiator, const u8 *extra_ies,
648 				       size_t extra_ies_len, u8 oper_class,
649 				       struct cfg80211_chan_def *chandef)
650 {
651 	struct ieee80211_tdls_data *tf;
652 	size_t offset = 0, noffset;
653 
654 	if (WARN_ON_ONCE(!chandef))
655 		return;
656 
657 	tf = (void *)skb->data;
658 	tf->u.chan_switch_req.target_channel =
659 		ieee80211_frequency_to_channel(chandef->chan->center_freq);
660 	tf->u.chan_switch_req.oper_class = oper_class;
661 
662 	if (extra_ies_len) {
663 		static const u8 before_lnkie[] = {
664 			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
665 		};
666 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
667 					     before_lnkie,
668 					     ARRAY_SIZE(before_lnkie),
669 					     offset);
670 		skb_put_data(skb, extra_ies + offset, noffset - offset);
671 		offset = noffset;
672 	}
673 
674 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
675 
676 	/* add any remaining IEs */
677 	if (extra_ies_len) {
678 		noffset = extra_ies_len;
679 		skb_put_data(skb, extra_ies + offset, noffset - offset);
680 	}
681 }
682 
683 static void
684 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
685 					struct sk_buff *skb, const u8 *peer,
686 					u16 status_code, bool initiator,
687 					const u8 *extra_ies,
688 					size_t extra_ies_len)
689 {
690 	if (status_code == 0)
691 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
692 
693 	if (extra_ies_len)
694 		skb_put_data(skb, extra_ies, extra_ies_len);
695 }
696 
697 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
698 				   struct sk_buff *skb, const u8 *peer,
699 				   u8 action_code, u16 status_code,
700 				   bool initiator, const u8 *extra_ies,
701 				   size_t extra_ies_len, u8 oper_class,
702 				   struct cfg80211_chan_def *chandef)
703 {
704 	switch (action_code) {
705 	case WLAN_TDLS_SETUP_REQUEST:
706 	case WLAN_TDLS_SETUP_RESPONSE:
707 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
708 		if (status_code == 0)
709 			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
710 							   action_code,
711 							   initiator,
712 							   extra_ies,
713 							   extra_ies_len);
714 		break;
715 	case WLAN_TDLS_SETUP_CONFIRM:
716 		if (status_code == 0)
717 			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
718 							 initiator, extra_ies,
719 							 extra_ies_len);
720 		break;
721 	case WLAN_TDLS_TEARDOWN:
722 	case WLAN_TDLS_DISCOVERY_REQUEST:
723 		if (extra_ies_len)
724 			skb_put_data(skb, extra_ies, extra_ies_len);
725 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
726 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
727 		break;
728 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
729 		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
730 						       initiator, extra_ies,
731 						       extra_ies_len,
732 						       oper_class, chandef);
733 		break;
734 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
735 		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
736 							status_code,
737 							initiator, extra_ies,
738 							extra_ies_len);
739 		break;
740 	}
741 
742 }
743 
744 static int
745 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
746 			       const u8 *peer, u8 action_code, u8 dialog_token,
747 			       u16 status_code, struct sk_buff *skb)
748 {
749 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
750 	struct ieee80211_tdls_data *tf;
751 
752 	tf = skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
753 
754 	memcpy(tf->da, peer, ETH_ALEN);
755 	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
756 	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
757 	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
758 
759 	/* network header is after the ethernet header */
760 	skb_set_network_header(skb, ETH_HLEN);
761 
762 	switch (action_code) {
763 	case WLAN_TDLS_SETUP_REQUEST:
764 		tf->category = WLAN_CATEGORY_TDLS;
765 		tf->action_code = WLAN_TDLS_SETUP_REQUEST;
766 
767 		skb_put(skb, sizeof(tf->u.setup_req));
768 		tf->u.setup_req.dialog_token = dialog_token;
769 		tf->u.setup_req.capability =
770 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
771 								 status_code));
772 		break;
773 	case WLAN_TDLS_SETUP_RESPONSE:
774 		tf->category = WLAN_CATEGORY_TDLS;
775 		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
776 
777 		skb_put(skb, sizeof(tf->u.setup_resp));
778 		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
779 		tf->u.setup_resp.dialog_token = dialog_token;
780 		tf->u.setup_resp.capability =
781 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
782 								 status_code));
783 		break;
784 	case WLAN_TDLS_SETUP_CONFIRM:
785 		tf->category = WLAN_CATEGORY_TDLS;
786 		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
787 
788 		skb_put(skb, sizeof(tf->u.setup_cfm));
789 		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
790 		tf->u.setup_cfm.dialog_token = dialog_token;
791 		break;
792 	case WLAN_TDLS_TEARDOWN:
793 		tf->category = WLAN_CATEGORY_TDLS;
794 		tf->action_code = WLAN_TDLS_TEARDOWN;
795 
796 		skb_put(skb, sizeof(tf->u.teardown));
797 		tf->u.teardown.reason_code = cpu_to_le16(status_code);
798 		break;
799 	case WLAN_TDLS_DISCOVERY_REQUEST:
800 		tf->category = WLAN_CATEGORY_TDLS;
801 		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
802 
803 		skb_put(skb, sizeof(tf->u.discover_req));
804 		tf->u.discover_req.dialog_token = dialog_token;
805 		break;
806 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
807 		tf->category = WLAN_CATEGORY_TDLS;
808 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
809 
810 		skb_put(skb, sizeof(tf->u.chan_switch_req));
811 		break;
812 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
813 		tf->category = WLAN_CATEGORY_TDLS;
814 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
815 
816 		skb_put(skb, sizeof(tf->u.chan_switch_resp));
817 		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
818 		break;
819 	default:
820 		return -EINVAL;
821 	}
822 
823 	return 0;
824 }
825 
826 static int
827 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
828 			   const u8 *peer, u8 action_code, u8 dialog_token,
829 			   u16 status_code, struct sk_buff *skb)
830 {
831 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
832 	struct ieee80211_mgmt *mgmt;
833 
834 	mgmt = skb_put_zero(skb, 24);
835 	memcpy(mgmt->da, peer, ETH_ALEN);
836 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
837 	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
838 
839 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
840 					  IEEE80211_STYPE_ACTION);
841 
842 	switch (action_code) {
843 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
844 		skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
845 		mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
846 		mgmt->u.action.u.tdls_discover_resp.action_code =
847 			WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
848 		mgmt->u.action.u.tdls_discover_resp.dialog_token =
849 			dialog_token;
850 		mgmt->u.action.u.tdls_discover_resp.capability =
851 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
852 								 status_code));
853 		break;
854 	default:
855 		return -EINVAL;
856 	}
857 
858 	return 0;
859 }
860 
861 static struct sk_buff *
862 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
863 				      const u8 *peer, u8 action_code,
864 				      u8 dialog_token, u16 status_code,
865 				      bool initiator, const u8 *extra_ies,
866 				      size_t extra_ies_len, u8 oper_class,
867 				      struct cfg80211_chan_def *chandef)
868 {
869 	struct ieee80211_local *local = sdata->local;
870 	struct sk_buff *skb;
871 	int ret;
872 
873 	skb = netdev_alloc_skb(sdata->dev,
874 			       local->hw.extra_tx_headroom +
875 			       max(sizeof(struct ieee80211_mgmt),
876 				   sizeof(struct ieee80211_tdls_data)) +
877 			       50 + /* supported rates */
878 			       10 + /* ext capab */
879 			       26 + /* max(WMM-info, WMM-param) */
880 			       2 + max(sizeof(struct ieee80211_ht_cap),
881 				       sizeof(struct ieee80211_ht_operation)) +
882 			       2 + max(sizeof(struct ieee80211_vht_cap),
883 				       sizeof(struct ieee80211_vht_operation)) +
884 			       50 + /* supported channels */
885 			       3 + /* 40/20 BSS coex */
886 			       4 + /* AID */
887 			       4 + /* oper classes */
888 			       extra_ies_len +
889 			       sizeof(struct ieee80211_tdls_lnkie));
890 	if (!skb)
891 		return NULL;
892 
893 	skb_reserve(skb, local->hw.extra_tx_headroom);
894 
895 	switch (action_code) {
896 	case WLAN_TDLS_SETUP_REQUEST:
897 	case WLAN_TDLS_SETUP_RESPONSE:
898 	case WLAN_TDLS_SETUP_CONFIRM:
899 	case WLAN_TDLS_TEARDOWN:
900 	case WLAN_TDLS_DISCOVERY_REQUEST:
901 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
902 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
903 		ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
904 						     sdata->dev, peer,
905 						     action_code, dialog_token,
906 						     status_code, skb);
907 		break;
908 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
909 		ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
910 						 peer, action_code,
911 						 dialog_token, status_code,
912 						 skb);
913 		break;
914 	default:
915 		ret = -ENOTSUPP;
916 		break;
917 	}
918 
919 	if (ret < 0)
920 		goto fail;
921 
922 	ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
923 			       initiator, extra_ies, extra_ies_len, oper_class,
924 			       chandef);
925 	return skb;
926 
927 fail:
928 	dev_kfree_skb(skb);
929 	return NULL;
930 }
931 
932 static int
933 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
934 				const u8 *peer, u8 action_code, u8 dialog_token,
935 				u16 status_code, u32 peer_capability,
936 				bool initiator, const u8 *extra_ies,
937 				size_t extra_ies_len, u8 oper_class,
938 				struct cfg80211_chan_def *chandef)
939 {
940 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
941 	struct sk_buff *skb = NULL;
942 	struct sta_info *sta;
943 	u32 flags = 0;
944 	int ret = 0;
945 
946 	rcu_read_lock();
947 	sta = sta_info_get(sdata, peer);
948 
949 	/* infer the initiator if we can, to support old userspace */
950 	switch (action_code) {
951 	case WLAN_TDLS_SETUP_REQUEST:
952 		if (sta) {
953 			set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
954 			sta->sta.tdls_initiator = false;
955 		}
956 		/* fall-through */
957 	case WLAN_TDLS_SETUP_CONFIRM:
958 	case WLAN_TDLS_DISCOVERY_REQUEST:
959 		initiator = true;
960 		break;
961 	case WLAN_TDLS_SETUP_RESPONSE:
962 		/*
963 		 * In some testing scenarios, we send a request and response.
964 		 * Make the last packet sent take effect for the initiator
965 		 * value.
966 		 */
967 		if (sta) {
968 			clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
969 			sta->sta.tdls_initiator = true;
970 		}
971 		/* fall-through */
972 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
973 		initiator = false;
974 		break;
975 	case WLAN_TDLS_TEARDOWN:
976 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
977 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
978 		/* any value is ok */
979 		break;
980 	default:
981 		ret = -ENOTSUPP;
982 		break;
983 	}
984 
985 	if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
986 		initiator = true;
987 
988 	rcu_read_unlock();
989 	if (ret < 0)
990 		goto fail;
991 
992 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
993 						    dialog_token, status_code,
994 						    initiator, extra_ies,
995 						    extra_ies_len, oper_class,
996 						    chandef);
997 	if (!skb) {
998 		ret = -EINVAL;
999 		goto fail;
1000 	}
1001 
1002 	if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
1003 		ieee80211_tx_skb(sdata, skb);
1004 		return 0;
1005 	}
1006 
1007 	/*
1008 	 * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
1009 	 * we should default to AC_VI.
1010 	 */
1011 	switch (action_code) {
1012 	case WLAN_TDLS_SETUP_REQUEST:
1013 	case WLAN_TDLS_SETUP_RESPONSE:
1014 		skb->priority = 256 + 2;
1015 		break;
1016 	default:
1017 		skb->priority = 256 + 5;
1018 		break;
1019 	}
1020 	skb_set_queue_mapping(skb, ieee80211_select_queue(sdata, skb));
1021 
1022 	/*
1023 	 * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
1024 	 * Later, if no ACK is returned from peer, we will re-send the teardown
1025 	 * packet through the AP.
1026 	 */
1027 	if ((action_code == WLAN_TDLS_TEARDOWN) &&
1028 	    ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
1029 		bool try_resend; /* Should we keep skb for possible resend */
1030 
1031 		/* If not sending directly to peer - no point in keeping skb */
1032 		rcu_read_lock();
1033 		sta = sta_info_get(sdata, peer);
1034 		try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1035 		rcu_read_unlock();
1036 
1037 		spin_lock_bh(&sdata->u.mgd.teardown_lock);
1038 		if (try_resend && !sdata->u.mgd.teardown_skb) {
1039 			/* Mark it as requiring TX status callback  */
1040 			flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
1041 				 IEEE80211_TX_INTFL_MLME_CONN_TX;
1042 
1043 			/*
1044 			 * skb is copied since mac80211 will later set
1045 			 * properties that might not be the same as the AP,
1046 			 * such as encryption, QoS, addresses, etc.
1047 			 *
1048 			 * No problem if skb_copy() fails, so no need to check.
1049 			 */
1050 			sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
1051 			sdata->u.mgd.orig_teardown_skb = skb;
1052 		}
1053 		spin_unlock_bh(&sdata->u.mgd.teardown_lock);
1054 	}
1055 
1056 	/* disable bottom halves when entering the Tx path */
1057 	local_bh_disable();
1058 	__ieee80211_subif_start_xmit(skb, dev, flags, 0);
1059 	local_bh_enable();
1060 
1061 	return ret;
1062 
1063 fail:
1064 	dev_kfree_skb(skb);
1065 	return ret;
1066 }
1067 
1068 static int
1069 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
1070 			  const u8 *peer, u8 action_code, u8 dialog_token,
1071 			  u16 status_code, u32 peer_capability, bool initiator,
1072 			  const u8 *extra_ies, size_t extra_ies_len)
1073 {
1074 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1075 	struct ieee80211_local *local = sdata->local;
1076 	enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
1077 	int ret;
1078 
1079 	/* don't support setup with forced SMPS mode that's not off */
1080 	if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
1081 	    smps_mode != IEEE80211_SMPS_OFF) {
1082 		tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
1083 			 smps_mode);
1084 		return -ENOTSUPP;
1085 	}
1086 
1087 	mutex_lock(&local->mtx);
1088 
1089 	/* we don't support concurrent TDLS peer setups */
1090 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
1091 	    !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1092 		ret = -EBUSY;
1093 		goto out_unlock;
1094 	}
1095 
1096 	/*
1097 	 * make sure we have a STA representing the peer so we drop or buffer
1098 	 * non-TDLS-setup frames to the peer. We can't send other packets
1099 	 * during setup through the AP path.
1100 	 * Allow error packets to be sent - sometimes we don't even add a STA
1101 	 * before failing the setup.
1102 	 */
1103 	if (status_code == 0) {
1104 		rcu_read_lock();
1105 		if (!sta_info_get(sdata, peer)) {
1106 			rcu_read_unlock();
1107 			ret = -ENOLINK;
1108 			goto out_unlock;
1109 		}
1110 		rcu_read_unlock();
1111 	}
1112 
1113 	ieee80211_flush_queues(local, sdata, false);
1114 	memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
1115 	mutex_unlock(&local->mtx);
1116 
1117 	/* we cannot take the mutex while preparing the setup packet */
1118 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1119 					      dialog_token, status_code,
1120 					      peer_capability, initiator,
1121 					      extra_ies, extra_ies_len, 0,
1122 					      NULL);
1123 	if (ret < 0) {
1124 		mutex_lock(&local->mtx);
1125 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1126 		mutex_unlock(&local->mtx);
1127 		return ret;
1128 	}
1129 
1130 	ieee80211_queue_delayed_work(&sdata->local->hw,
1131 				     &sdata->u.mgd.tdls_peer_del_work,
1132 				     TDLS_PEER_SETUP_TIMEOUT);
1133 	return 0;
1134 
1135 out_unlock:
1136 	mutex_unlock(&local->mtx);
1137 	return ret;
1138 }
1139 
1140 static int
1141 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
1142 			     const u8 *peer, u8 action_code, u8 dialog_token,
1143 			     u16 status_code, u32 peer_capability,
1144 			     bool initiator, const u8 *extra_ies,
1145 			     size_t extra_ies_len)
1146 {
1147 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1148 	struct ieee80211_local *local = sdata->local;
1149 	struct sta_info *sta;
1150 	int ret;
1151 
1152 	/*
1153 	 * No packets can be transmitted to the peer via the AP during setup -
1154 	 * the STA is set as a TDLS peer, but is not authorized.
1155 	 * During teardown, we prevent direct transmissions by stopping the
1156 	 * queues and flushing all direct packets.
1157 	 */
1158 	ieee80211_stop_vif_queues(local, sdata,
1159 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1160 	ieee80211_flush_queues(local, sdata, false);
1161 
1162 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1163 					      dialog_token, status_code,
1164 					      peer_capability, initiator,
1165 					      extra_ies, extra_ies_len, 0,
1166 					      NULL);
1167 	if (ret < 0)
1168 		sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
1169 			  ret);
1170 
1171 	/*
1172 	 * Remove the STA AUTH flag to force further traffic through the AP. If
1173 	 * the STA was unreachable, it was already removed.
1174 	 */
1175 	rcu_read_lock();
1176 	sta = sta_info_get(sdata, peer);
1177 	if (sta)
1178 		clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1179 	rcu_read_unlock();
1180 
1181 	ieee80211_wake_vif_queues(local, sdata,
1182 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1183 
1184 	return 0;
1185 }
1186 
1187 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
1188 			const u8 *peer, u8 action_code, u8 dialog_token,
1189 			u16 status_code, u32 peer_capability,
1190 			bool initiator, const u8 *extra_ies,
1191 			size_t extra_ies_len)
1192 {
1193 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1194 	int ret;
1195 
1196 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1197 		return -ENOTSUPP;
1198 
1199 	/* make sure we are in managed mode, and associated */
1200 	if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1201 	    !sdata->u.mgd.associated)
1202 		return -EINVAL;
1203 
1204 	switch (action_code) {
1205 	case WLAN_TDLS_SETUP_REQUEST:
1206 	case WLAN_TDLS_SETUP_RESPONSE:
1207 		ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1208 						dialog_token, status_code,
1209 						peer_capability, initiator,
1210 						extra_ies, extra_ies_len);
1211 		break;
1212 	case WLAN_TDLS_TEARDOWN:
1213 		ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1214 						   action_code, dialog_token,
1215 						   status_code,
1216 						   peer_capability, initiator,
1217 						   extra_ies, extra_ies_len);
1218 		break;
1219 	case WLAN_TDLS_DISCOVERY_REQUEST:
1220 		/*
1221 		 * Protect the discovery so we can hear the TDLS discovery
1222 		 * response frame. It is transmitted directly and not buffered
1223 		 * by the AP.
1224 		 */
1225 		drv_mgd_protect_tdls_discover(sdata->local, sdata);
1226 		/* fall-through */
1227 	case WLAN_TDLS_SETUP_CONFIRM:
1228 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1229 		/* no special handling */
1230 		ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1231 						      action_code,
1232 						      dialog_token,
1233 						      status_code,
1234 						      peer_capability,
1235 						      initiator, extra_ies,
1236 						      extra_ies_len, 0, NULL);
1237 		break;
1238 	default:
1239 		ret = -EOPNOTSUPP;
1240 		break;
1241 	}
1242 
1243 	tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1244 		 action_code, peer, ret);
1245 	return ret;
1246 }
1247 
1248 static void iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data *sdata,
1249 					 struct sta_info *sta)
1250 {
1251 	struct ieee80211_local *local = sdata->local;
1252 	struct ieee80211_chanctx_conf *conf;
1253 	struct ieee80211_chanctx *ctx;
1254 	enum nl80211_chan_width width;
1255 	struct ieee80211_supported_band *sband;
1256 
1257 	mutex_lock(&local->chanctx_mtx);
1258 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1259 					 lockdep_is_held(&local->chanctx_mtx));
1260 	if (conf) {
1261 		width = conf->def.width;
1262 		sband = local->hw.wiphy->bands[conf->def.chan->band];
1263 		ctx = container_of(conf, struct ieee80211_chanctx, conf);
1264 		ieee80211_recalc_chanctx_chantype(local, ctx);
1265 
1266 		/* if width changed and a peer is given, update its BW */
1267 		if (width != conf->def.width && sta &&
1268 		    test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW)) {
1269 			enum ieee80211_sta_rx_bandwidth bw;
1270 
1271 			bw = ieee80211_chan_width_to_rx_bw(conf->def.width);
1272 			bw = min(bw, ieee80211_sta_cap_rx_bw(sta));
1273 			if (bw != sta->sta.bandwidth) {
1274 				sta->sta.bandwidth = bw;
1275 				rate_control_rate_update(local, sband, sta,
1276 							 IEEE80211_RC_BW_CHANGED);
1277 				/*
1278 				 * if a TDLS peer BW was updated, we need to
1279 				 * recalc the chandef width again, to get the
1280 				 * correct chanctx min_def
1281 				 */
1282 				ieee80211_recalc_chanctx_chantype(local, ctx);
1283 			}
1284 		}
1285 
1286 	}
1287 	mutex_unlock(&local->chanctx_mtx);
1288 }
1289 
1290 static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
1291 {
1292 	struct sta_info *sta;
1293 	bool result = false;
1294 
1295 	rcu_read_lock();
1296 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1297 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1298 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
1299 		    !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
1300 		    !sta->sta.ht_cap.ht_supported)
1301 			continue;
1302 		result = true;
1303 		break;
1304 	}
1305 	rcu_read_unlock();
1306 
1307 	return result;
1308 }
1309 
1310 static void
1311 iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
1312 				   struct sta_info *sta)
1313 {
1314 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
1315 	bool tdls_ht;
1316 	u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
1317 			 IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
1318 			 IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
1319 	u16 opmode;
1320 
1321 	/* Nothing to do if the BSS connection uses HT */
1322 	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
1323 		return;
1324 
1325 	tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
1326 		  iee80211_tdls_have_ht_peers(sdata);
1327 
1328 	opmode = sdata->vif.bss_conf.ht_operation_mode;
1329 
1330 	if (tdls_ht)
1331 		opmode |= protection;
1332 	else
1333 		opmode &= ~protection;
1334 
1335 	if (opmode == sdata->vif.bss_conf.ht_operation_mode)
1336 		return;
1337 
1338 	sdata->vif.bss_conf.ht_operation_mode = opmode;
1339 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
1340 }
1341 
1342 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1343 			const u8 *peer, enum nl80211_tdls_operation oper)
1344 {
1345 	struct sta_info *sta;
1346 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1347 	struct ieee80211_local *local = sdata->local;
1348 	int ret;
1349 
1350 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1351 		return -ENOTSUPP;
1352 
1353 	if (sdata->vif.type != NL80211_IFTYPE_STATION)
1354 		return -EINVAL;
1355 
1356 	switch (oper) {
1357 	case NL80211_TDLS_ENABLE_LINK:
1358 	case NL80211_TDLS_DISABLE_LINK:
1359 		break;
1360 	case NL80211_TDLS_TEARDOWN:
1361 	case NL80211_TDLS_SETUP:
1362 	case NL80211_TDLS_DISCOVERY_REQ:
1363 		/* We don't support in-driver setup/teardown/discovery */
1364 		return -ENOTSUPP;
1365 	}
1366 
1367 	/* protect possible bss_conf changes and avoid concurrency in
1368 	 * ieee80211_bss_info_change_notify()
1369 	 */
1370 	sdata_lock(sdata);
1371 	mutex_lock(&local->mtx);
1372 	tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1373 
1374 	switch (oper) {
1375 	case NL80211_TDLS_ENABLE_LINK:
1376 		if (sdata->vif.csa_active) {
1377 			tdls_dbg(sdata, "TDLS: disallow link during CSA\n");
1378 			ret = -EBUSY;
1379 			break;
1380 		}
1381 
1382 		mutex_lock(&local->sta_mtx);
1383 		sta = sta_info_get(sdata, peer);
1384 		if (!sta) {
1385 			mutex_unlock(&local->sta_mtx);
1386 			ret = -ENOLINK;
1387 			break;
1388 		}
1389 
1390 		iee80211_tdls_recalc_chanctx(sdata, sta);
1391 		iee80211_tdls_recalc_ht_protection(sdata, sta);
1392 
1393 		set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1394 		mutex_unlock(&local->sta_mtx);
1395 
1396 		WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1397 			     !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1398 		ret = 0;
1399 		break;
1400 	case NL80211_TDLS_DISABLE_LINK:
1401 		/*
1402 		 * The teardown message in ieee80211_tdls_mgmt_teardown() was
1403 		 * created while the queues were stopped, so it might still be
1404 		 * pending. Before flushing the queues we need to be sure the
1405 		 * message is handled by the tasklet handling pending messages,
1406 		 * otherwise we might start destroying the station before
1407 		 * sending the teardown packet.
1408 		 * Note that this only forces the tasklet to flush pendings -
1409 		 * not to stop the tasklet from rescheduling itself.
1410 		 */
1411 		tasklet_kill(&local->tx_pending_tasklet);
1412 		/* flush a potentially queued teardown packet */
1413 		ieee80211_flush_queues(local, sdata, false);
1414 
1415 		ret = sta_info_destroy_addr(sdata, peer);
1416 
1417 		mutex_lock(&local->sta_mtx);
1418 		iee80211_tdls_recalc_ht_protection(sdata, NULL);
1419 		mutex_unlock(&local->sta_mtx);
1420 
1421 		iee80211_tdls_recalc_chanctx(sdata, NULL);
1422 		break;
1423 	default:
1424 		ret = -ENOTSUPP;
1425 		break;
1426 	}
1427 
1428 	if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1429 		cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1430 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1431 	}
1432 
1433 	if (ret == 0)
1434 		ieee80211_queue_work(&sdata->local->hw,
1435 				     &sdata->u.mgd.request_smps_work);
1436 
1437 	mutex_unlock(&local->mtx);
1438 	sdata_unlock(sdata);
1439 	return ret;
1440 }
1441 
1442 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1443 				 enum nl80211_tdls_operation oper,
1444 				 u16 reason_code, gfp_t gfp)
1445 {
1446 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1447 
1448 	if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1449 		sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1450 			  oper);
1451 		return;
1452 	}
1453 
1454 	cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1455 }
1456 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1457 
1458 static void
1459 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1460 {
1461 	struct ieee80211_ch_switch_timing *ch_sw;
1462 
1463 	*buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1464 	*buf++ = sizeof(struct ieee80211_ch_switch_timing);
1465 
1466 	ch_sw = (void *)buf;
1467 	ch_sw->switch_time = cpu_to_le16(switch_time);
1468 	ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1469 }
1470 
1471 /* find switch timing IE in SKB ready for Tx */
1472 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1473 {
1474 	struct ieee80211_tdls_data *tf;
1475 	const u8 *ie_start;
1476 
1477 	/*
1478 	 * Get the offset for the new location of the switch timing IE.
1479 	 * The SKB network header will now point to the "payload_type"
1480 	 * element of the TDLS data frame struct.
1481 	 */
1482 	tf = container_of(skb->data + skb_network_offset(skb),
1483 			  struct ieee80211_tdls_data, payload_type);
1484 	ie_start = tf->u.chan_switch_req.variable;
1485 	return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1486 				skb->len - (ie_start - skb->data));
1487 }
1488 
1489 static struct sk_buff *
1490 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1491 			      struct cfg80211_chan_def *chandef,
1492 			      u32 *ch_sw_tm_ie_offset)
1493 {
1494 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1495 	u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1496 		     2 + sizeof(struct ieee80211_ch_switch_timing)];
1497 	int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1498 	u8 *pos = extra_ies;
1499 	struct sk_buff *skb;
1500 
1501 	/*
1502 	 * if chandef points to a wide channel add a Secondary-Channel
1503 	 * Offset information element
1504 	 */
1505 	if (chandef->width == NL80211_CHAN_WIDTH_40) {
1506 		struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1507 		bool ht40plus;
1508 
1509 		*pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1510 		*pos++ = sizeof(*sec_chan_ie);
1511 		sec_chan_ie = (void *)pos;
1512 
1513 		ht40plus = cfg80211_get_chandef_type(chandef) ==
1514 							NL80211_CHAN_HT40PLUS;
1515 		sec_chan_ie->sec_chan_offs = ht40plus ?
1516 					     IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1517 					     IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1518 		pos += sizeof(*sec_chan_ie);
1519 
1520 		extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1521 	}
1522 
1523 	/* just set the values to 0, this is a template */
1524 	iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1525 
1526 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1527 					      WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1528 					      0, 0, !sta->sta.tdls_initiator,
1529 					      extra_ies, extra_ies_len,
1530 					      oper_class, chandef);
1531 	if (!skb)
1532 		return NULL;
1533 
1534 	skb = ieee80211_build_data_template(sdata, skb, 0);
1535 	if (IS_ERR(skb)) {
1536 		tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1537 		return NULL;
1538 	}
1539 
1540 	if (ch_sw_tm_ie_offset) {
1541 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1542 
1543 		if (!tm_ie) {
1544 			tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1545 			dev_kfree_skb_any(skb);
1546 			return NULL;
1547 		}
1548 
1549 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1550 	}
1551 
1552 	tdls_dbg(sdata,
1553 		 "TDLS channel switch request template for %pM ch %d width %d\n",
1554 		 sta->sta.addr, chandef->chan->center_freq, chandef->width);
1555 	return skb;
1556 }
1557 
1558 int
1559 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1560 			      const u8 *addr, u8 oper_class,
1561 			      struct cfg80211_chan_def *chandef)
1562 {
1563 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1564 	struct ieee80211_local *local = sdata->local;
1565 	struct sta_info *sta;
1566 	struct sk_buff *skb = NULL;
1567 	u32 ch_sw_tm_ie;
1568 	int ret;
1569 
1570 	mutex_lock(&local->sta_mtx);
1571 	sta = sta_info_get(sdata, addr);
1572 	if (!sta) {
1573 		tdls_dbg(sdata,
1574 			 "Invalid TDLS peer %pM for channel switch request\n",
1575 			 addr);
1576 		ret = -ENOENT;
1577 		goto out;
1578 	}
1579 
1580 	if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1581 		tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1582 			 addr);
1583 		ret = -ENOTSUPP;
1584 		goto out;
1585 	}
1586 
1587 	skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1588 					    &ch_sw_tm_ie);
1589 	if (!skb) {
1590 		ret = -ENOENT;
1591 		goto out;
1592 	}
1593 
1594 	ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1595 				      chandef, skb, ch_sw_tm_ie);
1596 	if (!ret)
1597 		set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1598 
1599 out:
1600 	mutex_unlock(&local->sta_mtx);
1601 	dev_kfree_skb_any(skb);
1602 	return ret;
1603 }
1604 
1605 void
1606 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1607 				     struct net_device *dev,
1608 				     const u8 *addr)
1609 {
1610 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1611 	struct ieee80211_local *local = sdata->local;
1612 	struct sta_info *sta;
1613 
1614 	mutex_lock(&local->sta_mtx);
1615 	sta = sta_info_get(sdata, addr);
1616 	if (!sta) {
1617 		tdls_dbg(sdata,
1618 			 "Invalid TDLS peer %pM for channel switch cancel\n",
1619 			 addr);
1620 		goto out;
1621 	}
1622 
1623 	if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1624 		tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1625 			 addr);
1626 		goto out;
1627 	}
1628 
1629 	drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1630 	clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1631 
1632 out:
1633 	mutex_unlock(&local->sta_mtx);
1634 }
1635 
1636 static struct sk_buff *
1637 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1638 				   u32 *ch_sw_tm_ie_offset)
1639 {
1640 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1641 	struct sk_buff *skb;
1642 	u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1643 
1644 	/* initial timing are always zero in the template */
1645 	iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1646 
1647 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1648 					WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1649 					0, 0, !sta->sta.tdls_initiator,
1650 					extra_ies, sizeof(extra_ies), 0, NULL);
1651 	if (!skb)
1652 		return NULL;
1653 
1654 	skb = ieee80211_build_data_template(sdata, skb, 0);
1655 	if (IS_ERR(skb)) {
1656 		tdls_dbg(sdata,
1657 			 "Failed building TDLS channel switch resp frame\n");
1658 		return NULL;
1659 	}
1660 
1661 	if (ch_sw_tm_ie_offset) {
1662 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1663 
1664 		if (!tm_ie) {
1665 			tdls_dbg(sdata,
1666 				 "No switch timing IE in TDLS switch resp\n");
1667 			dev_kfree_skb_any(skb);
1668 			return NULL;
1669 		}
1670 
1671 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1672 	}
1673 
1674 	tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1675 		 sta->sta.addr);
1676 	return skb;
1677 }
1678 
1679 static int
1680 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1681 					   struct sk_buff *skb)
1682 {
1683 	struct ieee80211_local *local = sdata->local;
1684 	struct ieee802_11_elems elems;
1685 	struct sta_info *sta;
1686 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1687 	bool local_initiator;
1688 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1689 	int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1690 	struct ieee80211_tdls_ch_sw_params params = {};
1691 	int ret;
1692 
1693 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1694 	params.timestamp = rx_status->device_timestamp;
1695 
1696 	if (skb->len < baselen) {
1697 		tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1698 			 skb->len);
1699 		return -EINVAL;
1700 	}
1701 
1702 	mutex_lock(&local->sta_mtx);
1703 	sta = sta_info_get(sdata, tf->sa);
1704 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1705 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1706 			 tf->sa);
1707 		ret = -EINVAL;
1708 		goto out;
1709 	}
1710 
1711 	params.sta = &sta->sta;
1712 	params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1713 	if (params.status != 0) {
1714 		ret = 0;
1715 		goto call_drv;
1716 	}
1717 
1718 	ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1719 			       skb->len - baselen, false, &elems,
1720 			       NULL, NULL);
1721 	if (elems.parse_error) {
1722 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1723 		ret = -EINVAL;
1724 		goto out;
1725 	}
1726 
1727 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1728 		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1729 		ret = -EINVAL;
1730 		goto out;
1731 	}
1732 
1733 	/* validate the initiator is set correctly */
1734 	local_initiator =
1735 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1736 	if (local_initiator == sta->sta.tdls_initiator) {
1737 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1738 		ret = -EINVAL;
1739 		goto out;
1740 	}
1741 
1742 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1743 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1744 
1745 	params.tmpl_skb =
1746 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1747 	if (!params.tmpl_skb) {
1748 		ret = -ENOENT;
1749 		goto out;
1750 	}
1751 
1752 	ret = 0;
1753 call_drv:
1754 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1755 
1756 	tdls_dbg(sdata,
1757 		 "TDLS channel switch response received from %pM status %d\n",
1758 		 tf->sa, params.status);
1759 
1760 out:
1761 	mutex_unlock(&local->sta_mtx);
1762 	dev_kfree_skb_any(params.tmpl_skb);
1763 	return ret;
1764 }
1765 
1766 static int
1767 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1768 					  struct sk_buff *skb)
1769 {
1770 	struct ieee80211_local *local = sdata->local;
1771 	struct ieee802_11_elems elems;
1772 	struct cfg80211_chan_def chandef;
1773 	struct ieee80211_channel *chan;
1774 	enum nl80211_channel_type chan_type;
1775 	int freq;
1776 	u8 target_channel, oper_class;
1777 	bool local_initiator;
1778 	struct sta_info *sta;
1779 	enum nl80211_band band;
1780 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1781 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1782 	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1783 	struct ieee80211_tdls_ch_sw_params params = {};
1784 	int ret = 0;
1785 
1786 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1787 	params.timestamp = rx_status->device_timestamp;
1788 
1789 	if (skb->len < baselen) {
1790 		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1791 			 skb->len);
1792 		return -EINVAL;
1793 	}
1794 
1795 	target_channel = tf->u.chan_switch_req.target_channel;
1796 	oper_class = tf->u.chan_switch_req.oper_class;
1797 
1798 	/*
1799 	 * We can't easily infer the channel band. The operating class is
1800 	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1801 	 * solution here is to treat channels with number >14 as 5GHz ones,
1802 	 * and specifically check for the (oper_class, channel) combinations
1803 	 * where this doesn't hold. These are thankfully unique according to
1804 	 * IEEE802.11-2012.
1805 	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1806 	 * valid here.
1807 	 */
1808 	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1809 	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1810 	     target_channel < 14)
1811 		band = NL80211_BAND_5GHZ;
1812 	else
1813 		band = target_channel < 14 ? NL80211_BAND_2GHZ :
1814 					     NL80211_BAND_5GHZ;
1815 
1816 	freq = ieee80211_channel_to_frequency(target_channel, band);
1817 	if (freq == 0) {
1818 		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1819 			 target_channel);
1820 		return -EINVAL;
1821 	}
1822 
1823 	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1824 	if (!chan) {
1825 		tdls_dbg(sdata,
1826 			 "Unsupported channel for TDLS chan switch: %d\n",
1827 			 target_channel);
1828 		return -EINVAL;
1829 	}
1830 
1831 	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1832 			       skb->len - baselen, false, &elems, NULL, NULL);
1833 	if (elems.parse_error) {
1834 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1835 		return -EINVAL;
1836 	}
1837 
1838 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1839 		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1840 		return -EINVAL;
1841 	}
1842 
1843 	if (!elems.sec_chan_offs) {
1844 		chan_type = NL80211_CHAN_HT20;
1845 	} else {
1846 		switch (elems.sec_chan_offs->sec_chan_offs) {
1847 		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1848 			chan_type = NL80211_CHAN_HT40PLUS;
1849 			break;
1850 		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1851 			chan_type = NL80211_CHAN_HT40MINUS;
1852 			break;
1853 		default:
1854 			chan_type = NL80211_CHAN_HT20;
1855 			break;
1856 		}
1857 	}
1858 
1859 	cfg80211_chandef_create(&chandef, chan, chan_type);
1860 
1861 	/* we will be active on the TDLS link */
1862 	if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1863 					   sdata->wdev.iftype)) {
1864 		tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1865 		return -EINVAL;
1866 	}
1867 
1868 	mutex_lock(&local->sta_mtx);
1869 	sta = sta_info_get(sdata, tf->sa);
1870 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1871 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1872 			 tf->sa);
1873 		ret = -EINVAL;
1874 		goto out;
1875 	}
1876 
1877 	params.sta = &sta->sta;
1878 
1879 	/* validate the initiator is set correctly */
1880 	local_initiator =
1881 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1882 	if (local_initiator == sta->sta.tdls_initiator) {
1883 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1884 		ret = -EINVAL;
1885 		goto out;
1886 	}
1887 
1888 	/* peer should have known better */
1889 	if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1890 	    elems.sec_chan_offs->sec_chan_offs) {
1891 		tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1892 		ret = -ENOTSUPP;
1893 		goto out;
1894 	}
1895 
1896 	params.chandef = &chandef;
1897 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1898 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1899 
1900 	params.tmpl_skb =
1901 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1902 						   &params.ch_sw_tm_ie);
1903 	if (!params.tmpl_skb) {
1904 		ret = -ENOENT;
1905 		goto out;
1906 	}
1907 
1908 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1909 
1910 	tdls_dbg(sdata,
1911 		 "TDLS ch switch request received from %pM ch %d width %d\n",
1912 		 tf->sa, params.chandef->chan->center_freq,
1913 		 params.chandef->width);
1914 out:
1915 	mutex_unlock(&local->sta_mtx);
1916 	dev_kfree_skb_any(params.tmpl_skb);
1917 	return ret;
1918 }
1919 
1920 static void
1921 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1922 				      struct sk_buff *skb)
1923 {
1924 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1925 	struct wiphy *wiphy = sdata->local->hw.wiphy;
1926 
1927 	ASSERT_RTNL();
1928 
1929 	/* make sure the driver supports it */
1930 	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1931 		return;
1932 
1933 	/* we want to access the entire packet */
1934 	if (skb_linearize(skb))
1935 		return;
1936 	/*
1937 	 * The packet/size was already validated by mac80211 Rx path, only look
1938 	 * at the action type.
1939 	 */
1940 	switch (tf->action_code) {
1941 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1942 		ieee80211_process_tdls_channel_switch_req(sdata, skb);
1943 		break;
1944 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1945 		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1946 		break;
1947 	default:
1948 		WARN_ON_ONCE(1);
1949 		return;
1950 	}
1951 }
1952 
1953 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1954 {
1955 	struct sta_info *sta;
1956 	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1957 
1958 	rcu_read_lock();
1959 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1960 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1961 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1962 			continue;
1963 
1964 		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1965 					    NL80211_TDLS_TEARDOWN, reason,
1966 					    GFP_ATOMIC);
1967 	}
1968 	rcu_read_unlock();
1969 }
1970 
1971 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1972 {
1973 	struct ieee80211_local *local =
1974 		container_of(wk, struct ieee80211_local, tdls_chsw_work);
1975 	struct ieee80211_sub_if_data *sdata;
1976 	struct sk_buff *skb;
1977 	struct ieee80211_tdls_data *tf;
1978 
1979 	rtnl_lock();
1980 	while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1981 		tf = (struct ieee80211_tdls_data *)skb->data;
1982 		list_for_each_entry(sdata, &local->interfaces, list) {
1983 			if (!ieee80211_sdata_running(sdata) ||
1984 			    sdata->vif.type != NL80211_IFTYPE_STATION ||
1985 			    !ether_addr_equal(tf->da, sdata->vif.addr))
1986 				continue;
1987 
1988 			ieee80211_process_tdls_channel_switch(sdata, skb);
1989 			break;
1990 		}
1991 
1992 		kfree_skb(skb);
1993 	}
1994 	rtnl_unlock();
1995 }
1996 
1997 void ieee80211_tdls_handle_disconnect(struct ieee80211_sub_if_data *sdata,
1998 				      const u8 *peer, u16 reason)
1999 {
2000 	struct ieee80211_sta *sta;
2001 
2002 	rcu_read_lock();
2003 	sta = ieee80211_find_sta(&sdata->vif, peer);
2004 	if (!sta || !sta->tdls) {
2005 		rcu_read_unlock();
2006 		return;
2007 	}
2008 	rcu_read_unlock();
2009 
2010 	tdls_dbg(sdata, "disconnected from TDLS peer %pM (Reason: %u=%s)\n",
2011 		 peer, reason,
2012 		 ieee80211_get_reason_code_string(reason));
2013 
2014 	ieee80211_tdls_oper_request(&sdata->vif, peer,
2015 				    NL80211_TDLS_TEARDOWN,
2016 				    WLAN_REASON_TDLS_TEARDOWN_UNREACHABLE,
2017 				    GFP_ATOMIC);
2018 }
2019