xref: /linux/net/mac80211/tdls.c (revision 80d443e8876602be2c130f79c4de81e12e2a700d)
1 /*
2  * mac80211 TDLS handling code
3  *
4  * Copyright 2006-2010	Johannes Berg <johannes@sipsolutions.net>
5  * Copyright 2014, Intel Corporation
6  * Copyright 2014  Intel Mobile Communications GmbH
7  * Copyright 2015 - 2016 Intel Deutschland GmbH
8  *
9  * This file is GPLv2 as found in COPYING.
10  */
11 
12 #include <linux/ieee80211.h>
13 #include <linux/log2.h>
14 #include <net/cfg80211.h>
15 #include <linux/rtnetlink.h>
16 #include "ieee80211_i.h"
17 #include "driver-ops.h"
18 #include "rate.h"
19 
20 /* give usermode some time for retries in setting up the TDLS session */
21 #define TDLS_PEER_SETUP_TIMEOUT	(15 * HZ)
22 
23 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
24 {
25 	struct ieee80211_sub_if_data *sdata;
26 	struct ieee80211_local *local;
27 
28 	sdata = container_of(wk, struct ieee80211_sub_if_data,
29 			     u.mgd.tdls_peer_del_work.work);
30 	local = sdata->local;
31 
32 	mutex_lock(&local->mtx);
33 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
34 		tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
35 		sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
36 		eth_zero_addr(sdata->u.mgd.tdls_peer);
37 	}
38 	mutex_unlock(&local->mtx);
39 }
40 
41 static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
42 					 struct sk_buff *skb)
43 {
44 	struct ieee80211_local *local = sdata->local;
45 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
46 	bool chan_switch = local->hw.wiphy->features &
47 			   NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
48 	bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW) &&
49 			  !ifmgd->tdls_wider_bw_prohibited;
50 	enum nl80211_band band = ieee80211_get_sdata_band(sdata);
51 	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
52 	bool vht = sband && sband->vht_cap.vht_supported;
53 	u8 *pos = (void *)skb_put(skb, 10);
54 
55 	*pos++ = WLAN_EID_EXT_CAPABILITY;
56 	*pos++ = 8; /* len */
57 	*pos++ = 0x0;
58 	*pos++ = 0x0;
59 	*pos++ = 0x0;
60 	*pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
61 	*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
62 	*pos++ = 0;
63 	*pos++ = 0;
64 	*pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
65 }
66 
67 static u8
68 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
69 			   struct sk_buff *skb, u16 start, u16 end,
70 			   u16 spacing)
71 {
72 	u8 subband_cnt = 0, ch_cnt = 0;
73 	struct ieee80211_channel *ch;
74 	struct cfg80211_chan_def chandef;
75 	int i, subband_start;
76 	struct wiphy *wiphy = sdata->local->hw.wiphy;
77 
78 	for (i = start; i <= end; i += spacing) {
79 		if (!ch_cnt)
80 			subband_start = i;
81 
82 		ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
83 		if (ch) {
84 			/* we will be active on the channel */
85 			cfg80211_chandef_create(&chandef, ch,
86 						NL80211_CHAN_NO_HT);
87 			if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
88 							  sdata->wdev.iftype)) {
89 				ch_cnt++;
90 				/*
91 				 * check if the next channel is also part of
92 				 * this allowed range
93 				 */
94 				continue;
95 			}
96 		}
97 
98 		/*
99 		 * we've reached the end of a range, with allowed channels
100 		 * found
101 		 */
102 		if (ch_cnt) {
103 			u8 *pos = skb_put(skb, 2);
104 			*pos++ = ieee80211_frequency_to_channel(subband_start);
105 			*pos++ = ch_cnt;
106 
107 			subband_cnt++;
108 			ch_cnt = 0;
109 		}
110 	}
111 
112 	/* all channels in the requested range are allowed - add them here */
113 	if (ch_cnt) {
114 		u8 *pos = skb_put(skb, 2);
115 		*pos++ = ieee80211_frequency_to_channel(subband_start);
116 		*pos++ = ch_cnt;
117 
118 		subband_cnt++;
119 	}
120 
121 	return subband_cnt;
122 }
123 
124 static void
125 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
126 				 struct sk_buff *skb)
127 {
128 	/*
129 	 * Add possible channels for TDLS. These are channels that are allowed
130 	 * to be active.
131 	 */
132 	u8 subband_cnt;
133 	u8 *pos = skb_put(skb, 2);
134 
135 	*pos++ = WLAN_EID_SUPPORTED_CHANNELS;
136 
137 	/*
138 	 * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
139 	 * this doesn't happen in real world scenarios.
140 	 */
141 
142 	/* 2GHz, with 5MHz spacing */
143 	subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
144 
145 	/* 5GHz, with 20MHz spacing */
146 	subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
147 
148 	/* length */
149 	*pos = 2 * subband_cnt;
150 }
151 
152 static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
153 					    struct sk_buff *skb)
154 {
155 	u8 *pos;
156 	u8 op_class;
157 
158 	if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
159 						  &op_class))
160 		return;
161 
162 	pos = skb_put(skb, 4);
163 	*pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
164 	*pos++ = 2; /* len */
165 
166 	*pos++ = op_class;
167 	*pos++ = op_class; /* give current operating class as alternate too */
168 }
169 
170 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
171 {
172 	u8 *pos = (void *)skb_put(skb, 3);
173 
174 	*pos++ = WLAN_EID_BSS_COEX_2040;
175 	*pos++ = 1; /* len */
176 
177 	*pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
178 }
179 
180 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
181 					u16 status_code)
182 {
183 	/* The capability will be 0 when sending a failure code */
184 	if (status_code != 0)
185 		return 0;
186 
187 	if (ieee80211_get_sdata_band(sdata) == NL80211_BAND_2GHZ) {
188 		return WLAN_CAPABILITY_SHORT_SLOT_TIME |
189 		       WLAN_CAPABILITY_SHORT_PREAMBLE;
190 	}
191 
192 	return 0;
193 }
194 
195 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
196 				       struct sk_buff *skb, const u8 *peer,
197 				       bool initiator)
198 {
199 	struct ieee80211_tdls_lnkie *lnkid;
200 	const u8 *init_addr, *rsp_addr;
201 
202 	if (initiator) {
203 		init_addr = sdata->vif.addr;
204 		rsp_addr = peer;
205 	} else {
206 		init_addr = peer;
207 		rsp_addr = sdata->vif.addr;
208 	}
209 
210 	lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
211 
212 	lnkid->ie_type = WLAN_EID_LINK_ID;
213 	lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
214 
215 	memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
216 	memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
217 	memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
218 }
219 
220 static void
221 ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
222 {
223 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
224 	u8 *pos = (void *)skb_put(skb, 4);
225 
226 	*pos++ = WLAN_EID_AID;
227 	*pos++ = 2; /* len */
228 	put_unaligned_le16(ifmgd->aid, pos);
229 }
230 
231 /* translate numbering in the WMM parameter IE to the mac80211 notation */
232 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
233 {
234 	switch (ac) {
235 	default:
236 		WARN_ON_ONCE(1);
237 	case 0:
238 		return IEEE80211_AC_BE;
239 	case 1:
240 		return IEEE80211_AC_BK;
241 	case 2:
242 		return IEEE80211_AC_VI;
243 	case 3:
244 		return IEEE80211_AC_VO;
245 	}
246 }
247 
248 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
249 {
250 	u8 ret;
251 
252 	ret = aifsn & 0x0f;
253 	if (acm)
254 		ret |= 0x10;
255 	ret |= (aci << 5) & 0x60;
256 	return ret;
257 }
258 
259 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
260 {
261 	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
262 	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
263 }
264 
265 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
266 					    struct sk_buff *skb)
267 {
268 	struct ieee80211_wmm_param_ie *wmm;
269 	struct ieee80211_tx_queue_params *txq;
270 	int i;
271 
272 	wmm = (void *)skb_put(skb, sizeof(*wmm));
273 	memset(wmm, 0, sizeof(*wmm));
274 
275 	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
276 	wmm->len = sizeof(*wmm) - 2;
277 
278 	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
279 	wmm->oui[1] = 0x50;
280 	wmm->oui[2] = 0xf2;
281 	wmm->oui_type = 2; /* WME */
282 	wmm->oui_subtype = 1; /* WME param */
283 	wmm->version = 1; /* WME ver */
284 	wmm->qos_info = 0; /* U-APSD not in use */
285 
286 	/*
287 	 * Use the EDCA parameters defined for the BSS, or default if the AP
288 	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
289 	 */
290 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
291 		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
292 		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
293 							       txq->acm, i);
294 		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
295 		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
296 	}
297 }
298 
299 static void
300 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
301 				   struct sta_info *sta)
302 {
303 	/* IEEE802.11ac-2013 Table E-4 */
304 	u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
305 	struct cfg80211_chan_def uc = sta->tdls_chandef;
306 	enum nl80211_chan_width max_width = ieee80211_sta_cap_chan_bw(sta);
307 	int i;
308 
309 	/* only support upgrading non-narrow channels up to 80Mhz */
310 	if (max_width == NL80211_CHAN_WIDTH_5 ||
311 	    max_width == NL80211_CHAN_WIDTH_10)
312 		return;
313 
314 	if (max_width > NL80211_CHAN_WIDTH_80)
315 		max_width = NL80211_CHAN_WIDTH_80;
316 
317 	if (uc.width >= max_width)
318 		return;
319 	/*
320 	 * Channel usage constrains in the IEEE802.11ac-2013 specification only
321 	 * allow expanding a 20MHz channel to 80MHz in a single way. In
322 	 * addition, there are no 40MHz allowed channels that are not part of
323 	 * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
324 	 */
325 	for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
326 		if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
327 			uc.center_freq1 = centers_80mhz[i];
328 			uc.center_freq2 = 0;
329 			uc.width = NL80211_CHAN_WIDTH_80;
330 			break;
331 		}
332 
333 	if (!uc.center_freq1)
334 		return;
335 
336 	/* proceed to downgrade the chandef until usable or the same as AP BW */
337 	while (uc.width > max_width ||
338 	       (uc.width > sta->tdls_chandef.width &&
339 		!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &uc,
340 					       sdata->wdev.iftype)))
341 		ieee80211_chandef_downgrade(&uc);
342 
343 	if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
344 		tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
345 			 sta->tdls_chandef.width, uc.width);
346 
347 		/*
348 		 * the station is not yet authorized when BW upgrade is done,
349 		 * locking is not required
350 		 */
351 		sta->tdls_chandef = uc;
352 	}
353 }
354 
355 static void
356 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
357 				   struct sk_buff *skb, const u8 *peer,
358 				   u8 action_code, bool initiator,
359 				   const u8 *extra_ies, size_t extra_ies_len)
360 {
361 	enum nl80211_band band = ieee80211_get_sdata_band(sdata);
362 	struct ieee80211_local *local = sdata->local;
363 	struct ieee80211_supported_band *sband;
364 	struct ieee80211_sta_ht_cap ht_cap;
365 	struct ieee80211_sta_vht_cap vht_cap;
366 	struct sta_info *sta = NULL;
367 	size_t offset = 0, noffset;
368 	u8 *pos;
369 
370 	ieee80211_add_srates_ie(sdata, skb, false, band);
371 	ieee80211_add_ext_srates_ie(sdata, skb, false, band);
372 	ieee80211_tdls_add_supp_channels(sdata, skb);
373 
374 	/* add any custom IEs that go before Extended Capabilities */
375 	if (extra_ies_len) {
376 		static const u8 before_ext_cap[] = {
377 			WLAN_EID_SUPP_RATES,
378 			WLAN_EID_COUNTRY,
379 			WLAN_EID_EXT_SUPP_RATES,
380 			WLAN_EID_SUPPORTED_CHANNELS,
381 			WLAN_EID_RSN,
382 		};
383 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
384 					     before_ext_cap,
385 					     ARRAY_SIZE(before_ext_cap),
386 					     offset);
387 		pos = skb_put(skb, noffset - offset);
388 		memcpy(pos, extra_ies + offset, noffset - offset);
389 		offset = noffset;
390 	}
391 
392 	ieee80211_tdls_add_ext_capab(sdata, skb);
393 
394 	/* add the QoS element if we support it */
395 	if (local->hw.queues >= IEEE80211_NUM_ACS &&
396 	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
397 		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
398 
399 	/* add any custom IEs that go before HT capabilities */
400 	if (extra_ies_len) {
401 		static const u8 before_ht_cap[] = {
402 			WLAN_EID_SUPP_RATES,
403 			WLAN_EID_COUNTRY,
404 			WLAN_EID_EXT_SUPP_RATES,
405 			WLAN_EID_SUPPORTED_CHANNELS,
406 			WLAN_EID_RSN,
407 			WLAN_EID_EXT_CAPABILITY,
408 			WLAN_EID_QOS_CAPA,
409 			WLAN_EID_FAST_BSS_TRANSITION,
410 			WLAN_EID_TIMEOUT_INTERVAL,
411 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
412 		};
413 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
414 					     before_ht_cap,
415 					     ARRAY_SIZE(before_ht_cap),
416 					     offset);
417 		pos = skb_put(skb, noffset - offset);
418 		memcpy(pos, extra_ies + offset, noffset - offset);
419 		offset = noffset;
420 	}
421 
422 	mutex_lock(&local->sta_mtx);
423 
424 	/* we should have the peer STA if we're already responding */
425 	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
426 		sta = sta_info_get(sdata, peer);
427 		if (WARN_ON_ONCE(!sta)) {
428 			mutex_unlock(&local->sta_mtx);
429 			return;
430 		}
431 
432 		sta->tdls_chandef = sdata->vif.bss_conf.chandef;
433 	}
434 
435 	ieee80211_tdls_add_oper_classes(sdata, skb);
436 
437 	/*
438 	 * with TDLS we can switch channels, and HT-caps are not necessarily
439 	 * the same on all bands. The specification limits the setup to a
440 	 * single HT-cap, so use the current band for now.
441 	 */
442 	sband = local->hw.wiphy->bands[band];
443 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
444 
445 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
446 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
447 	    ht_cap.ht_supported) {
448 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
449 
450 		/* disable SMPS in TDLS initiator */
451 		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
452 				<< IEEE80211_HT_CAP_SM_PS_SHIFT;
453 
454 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
455 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
456 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
457 		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
458 		/* the peer caps are already intersected with our own */
459 		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
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 	}
464 
465 	if (ht_cap.ht_supported &&
466 	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
467 		ieee80211_tdls_add_bss_coex_ie(skb);
468 
469 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
470 
471 	/* add any custom IEs that go before VHT capabilities */
472 	if (extra_ies_len) {
473 		static const u8 before_vht_cap[] = {
474 			WLAN_EID_SUPP_RATES,
475 			WLAN_EID_COUNTRY,
476 			WLAN_EID_EXT_SUPP_RATES,
477 			WLAN_EID_SUPPORTED_CHANNELS,
478 			WLAN_EID_RSN,
479 			WLAN_EID_EXT_CAPABILITY,
480 			WLAN_EID_QOS_CAPA,
481 			WLAN_EID_FAST_BSS_TRANSITION,
482 			WLAN_EID_TIMEOUT_INTERVAL,
483 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
484 			WLAN_EID_MULTI_BAND,
485 		};
486 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
487 					     before_vht_cap,
488 					     ARRAY_SIZE(before_vht_cap),
489 					     offset);
490 		pos = skb_put(skb, noffset - offset);
491 		memcpy(pos, extra_ies + offset, noffset - offset);
492 		offset = noffset;
493 	}
494 
495 	/* build the VHT-cap similarly to the HT-cap */
496 	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
497 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
498 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
499 	    vht_cap.vht_supported) {
500 		ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
501 
502 		/* the AID is present only when VHT is implemented */
503 		if (action_code == WLAN_TDLS_SETUP_REQUEST)
504 			ieee80211_tdls_add_aid(sdata, skb);
505 
506 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
507 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
508 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
509 		   vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
510 		/* the peer caps are already intersected with our own */
511 		memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
512 
513 		/* the AID is present only when VHT is implemented */
514 		ieee80211_tdls_add_aid(sdata, skb);
515 
516 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
517 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
518 
519 		/*
520 		 * if both peers support WIDER_BW, we can expand the chandef to
521 		 * a wider compatible one, up to 80MHz
522 		 */
523 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
524 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
525 	}
526 
527 	mutex_unlock(&local->sta_mtx);
528 
529 	/* add any remaining IEs */
530 	if (extra_ies_len) {
531 		noffset = extra_ies_len;
532 		pos = skb_put(skb, noffset - offset);
533 		memcpy(pos, extra_ies + offset, noffset - offset);
534 	}
535 
536 }
537 
538 static void
539 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
540 				 struct sk_buff *skb, const u8 *peer,
541 				 bool initiator, const u8 *extra_ies,
542 				 size_t extra_ies_len)
543 {
544 	struct ieee80211_local *local = sdata->local;
545 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
546 	size_t offset = 0, noffset;
547 	struct sta_info *sta, *ap_sta;
548 	enum nl80211_band band = ieee80211_get_sdata_band(sdata);
549 	u8 *pos;
550 
551 	mutex_lock(&local->sta_mtx);
552 
553 	sta = sta_info_get(sdata, peer);
554 	ap_sta = sta_info_get(sdata, ifmgd->bssid);
555 	if (WARN_ON_ONCE(!sta || !ap_sta)) {
556 		mutex_unlock(&local->sta_mtx);
557 		return;
558 	}
559 
560 	sta->tdls_chandef = sdata->vif.bss_conf.chandef;
561 
562 	/* add any custom IEs that go before the QoS IE */
563 	if (extra_ies_len) {
564 		static const u8 before_qos[] = {
565 			WLAN_EID_RSN,
566 		};
567 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
568 					     before_qos,
569 					     ARRAY_SIZE(before_qos),
570 					     offset);
571 		pos = skb_put(skb, noffset - offset);
572 		memcpy(pos, extra_ies + offset, noffset - offset);
573 		offset = noffset;
574 	}
575 
576 	/* add the QoS param IE if both the peer and we support it */
577 	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
578 		ieee80211_tdls_add_wmm_param_ie(sdata, skb);
579 
580 	/* add any custom IEs that go before HT operation */
581 	if (extra_ies_len) {
582 		static const u8 before_ht_op[] = {
583 			WLAN_EID_RSN,
584 			WLAN_EID_QOS_CAPA,
585 			WLAN_EID_FAST_BSS_TRANSITION,
586 			WLAN_EID_TIMEOUT_INTERVAL,
587 		};
588 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
589 					     before_ht_op,
590 					     ARRAY_SIZE(before_ht_op),
591 					     offset);
592 		pos = skb_put(skb, noffset - offset);
593 		memcpy(pos, extra_ies + offset, noffset - offset);
594 		offset = noffset;
595 	}
596 
597 	/*
598 	 * if HT support is only added in TDLS, we need an HT-operation IE.
599 	 * add the IE as required by IEEE802.11-2012 9.23.3.2.
600 	 */
601 	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
602 		u16 prot = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
603 			   IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
604 			   IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
605 
606 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
607 		ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
608 					   &sdata->vif.bss_conf.chandef, prot,
609 					   true);
610 	}
611 
612 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
613 
614 	/* only include VHT-operation if not on the 2.4GHz band */
615 	if (band != NL80211_BAND_2GHZ && sta->sta.vht_cap.vht_supported) {
616 		/*
617 		 * if both peers support WIDER_BW, we can expand the chandef to
618 		 * a wider compatible one, up to 80MHz
619 		 */
620 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
621 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
622 
623 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
624 		ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
625 					    &sta->tdls_chandef);
626 	}
627 
628 	mutex_unlock(&local->sta_mtx);
629 
630 	/* add any remaining IEs */
631 	if (extra_ies_len) {
632 		noffset = extra_ies_len;
633 		pos = skb_put(skb, noffset - offset);
634 		memcpy(pos, extra_ies + offset, noffset - offset);
635 	}
636 }
637 
638 static void
639 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
640 				       struct sk_buff *skb, const u8 *peer,
641 				       bool initiator, const u8 *extra_ies,
642 				       size_t extra_ies_len, u8 oper_class,
643 				       struct cfg80211_chan_def *chandef)
644 {
645 	struct ieee80211_tdls_data *tf;
646 	size_t offset = 0, noffset;
647 	u8 *pos;
648 
649 	if (WARN_ON_ONCE(!chandef))
650 		return;
651 
652 	tf = (void *)skb->data;
653 	tf->u.chan_switch_req.target_channel =
654 		ieee80211_frequency_to_channel(chandef->chan->center_freq);
655 	tf->u.chan_switch_req.oper_class = oper_class;
656 
657 	if (extra_ies_len) {
658 		static const u8 before_lnkie[] = {
659 			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
660 		};
661 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
662 					     before_lnkie,
663 					     ARRAY_SIZE(before_lnkie),
664 					     offset);
665 		pos = skb_put(skb, noffset - offset);
666 		memcpy(pos, extra_ies + offset, noffset - offset);
667 		offset = noffset;
668 	}
669 
670 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
671 
672 	/* add any remaining IEs */
673 	if (extra_ies_len) {
674 		noffset = extra_ies_len;
675 		pos = skb_put(skb, noffset - offset);
676 		memcpy(pos, extra_ies + offset, noffset - offset);
677 	}
678 }
679 
680 static void
681 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
682 					struct sk_buff *skb, const u8 *peer,
683 					u16 status_code, bool initiator,
684 					const u8 *extra_ies,
685 					size_t extra_ies_len)
686 {
687 	if (status_code == 0)
688 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
689 
690 	if (extra_ies_len)
691 		memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
692 }
693 
694 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
695 				   struct sk_buff *skb, const u8 *peer,
696 				   u8 action_code, u16 status_code,
697 				   bool initiator, const u8 *extra_ies,
698 				   size_t extra_ies_len, u8 oper_class,
699 				   struct cfg80211_chan_def *chandef)
700 {
701 	switch (action_code) {
702 	case WLAN_TDLS_SETUP_REQUEST:
703 	case WLAN_TDLS_SETUP_RESPONSE:
704 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
705 		if (status_code == 0)
706 			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
707 							   action_code,
708 							   initiator,
709 							   extra_ies,
710 							   extra_ies_len);
711 		break;
712 	case WLAN_TDLS_SETUP_CONFIRM:
713 		if (status_code == 0)
714 			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
715 							 initiator, extra_ies,
716 							 extra_ies_len);
717 		break;
718 	case WLAN_TDLS_TEARDOWN:
719 	case WLAN_TDLS_DISCOVERY_REQUEST:
720 		if (extra_ies_len)
721 			memcpy(skb_put(skb, extra_ies_len), extra_ies,
722 			       extra_ies_len);
723 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
724 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
725 		break;
726 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
727 		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
728 						       initiator, extra_ies,
729 						       extra_ies_len,
730 						       oper_class, chandef);
731 		break;
732 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
733 		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
734 							status_code,
735 							initiator, extra_ies,
736 							extra_ies_len);
737 		break;
738 	}
739 
740 }
741 
742 static int
743 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
744 			       const u8 *peer, u8 action_code, u8 dialog_token,
745 			       u16 status_code, struct sk_buff *skb)
746 {
747 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
748 	struct ieee80211_tdls_data *tf;
749 
750 	tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
751 
752 	memcpy(tf->da, peer, ETH_ALEN);
753 	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
754 	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
755 	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
756 
757 	/* network header is after the ethernet header */
758 	skb_set_network_header(skb, ETH_HLEN);
759 
760 	switch (action_code) {
761 	case WLAN_TDLS_SETUP_REQUEST:
762 		tf->category = WLAN_CATEGORY_TDLS;
763 		tf->action_code = WLAN_TDLS_SETUP_REQUEST;
764 
765 		skb_put(skb, sizeof(tf->u.setup_req));
766 		tf->u.setup_req.dialog_token = dialog_token;
767 		tf->u.setup_req.capability =
768 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
769 								 status_code));
770 		break;
771 	case WLAN_TDLS_SETUP_RESPONSE:
772 		tf->category = WLAN_CATEGORY_TDLS;
773 		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
774 
775 		skb_put(skb, sizeof(tf->u.setup_resp));
776 		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
777 		tf->u.setup_resp.dialog_token = dialog_token;
778 		tf->u.setup_resp.capability =
779 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
780 								 status_code));
781 		break;
782 	case WLAN_TDLS_SETUP_CONFIRM:
783 		tf->category = WLAN_CATEGORY_TDLS;
784 		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
785 
786 		skb_put(skb, sizeof(tf->u.setup_cfm));
787 		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
788 		tf->u.setup_cfm.dialog_token = dialog_token;
789 		break;
790 	case WLAN_TDLS_TEARDOWN:
791 		tf->category = WLAN_CATEGORY_TDLS;
792 		tf->action_code = WLAN_TDLS_TEARDOWN;
793 
794 		skb_put(skb, sizeof(tf->u.teardown));
795 		tf->u.teardown.reason_code = cpu_to_le16(status_code);
796 		break;
797 	case WLAN_TDLS_DISCOVERY_REQUEST:
798 		tf->category = WLAN_CATEGORY_TDLS;
799 		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
800 
801 		skb_put(skb, sizeof(tf->u.discover_req));
802 		tf->u.discover_req.dialog_token = dialog_token;
803 		break;
804 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
805 		tf->category = WLAN_CATEGORY_TDLS;
806 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
807 
808 		skb_put(skb, sizeof(tf->u.chan_switch_req));
809 		break;
810 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
811 		tf->category = WLAN_CATEGORY_TDLS;
812 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
813 
814 		skb_put(skb, sizeof(tf->u.chan_switch_resp));
815 		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
816 		break;
817 	default:
818 		return -EINVAL;
819 	}
820 
821 	return 0;
822 }
823 
824 static int
825 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
826 			   const u8 *peer, u8 action_code, u8 dialog_token,
827 			   u16 status_code, struct sk_buff *skb)
828 {
829 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
830 	struct ieee80211_mgmt *mgmt;
831 
832 	mgmt = (void *)skb_put(skb, 24);
833 	memset(mgmt, 0, 24);
834 	memcpy(mgmt->da, peer, ETH_ALEN);
835 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
836 	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
837 
838 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
839 					  IEEE80211_STYPE_ACTION);
840 
841 	switch (action_code) {
842 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
843 		skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
844 		mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
845 		mgmt->u.action.u.tdls_discover_resp.action_code =
846 			WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
847 		mgmt->u.action.u.tdls_discover_resp.dialog_token =
848 			dialog_token;
849 		mgmt->u.action.u.tdls_discover_resp.capability =
850 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
851 								 status_code));
852 		break;
853 	default:
854 		return -EINVAL;
855 	}
856 
857 	return 0;
858 }
859 
860 static struct sk_buff *
861 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
862 				      const u8 *peer, u8 action_code,
863 				      u8 dialog_token, u16 status_code,
864 				      bool initiator, const u8 *extra_ies,
865 				      size_t extra_ies_len, u8 oper_class,
866 				      struct cfg80211_chan_def *chandef)
867 {
868 	struct ieee80211_local *local = sdata->local;
869 	struct sk_buff *skb;
870 	int ret;
871 
872 	skb = netdev_alloc_skb(sdata->dev,
873 			       local->hw.extra_tx_headroom +
874 			       max(sizeof(struct ieee80211_mgmt),
875 				   sizeof(struct ieee80211_tdls_data)) +
876 			       50 + /* supported rates */
877 			       10 + /* ext capab */
878 			       26 + /* max(WMM-info, WMM-param) */
879 			       2 + max(sizeof(struct ieee80211_ht_cap),
880 				       sizeof(struct ieee80211_ht_operation)) +
881 			       2 + max(sizeof(struct ieee80211_vht_cap),
882 				       sizeof(struct ieee80211_vht_operation)) +
883 			       50 + /* supported channels */
884 			       3 + /* 40/20 BSS coex */
885 			       4 + /* AID */
886 			       4 + /* oper classes */
887 			       extra_ies_len +
888 			       sizeof(struct ieee80211_tdls_lnkie));
889 	if (!skb)
890 		return NULL;
891 
892 	skb_reserve(skb, local->hw.extra_tx_headroom);
893 
894 	switch (action_code) {
895 	case WLAN_TDLS_SETUP_REQUEST:
896 	case WLAN_TDLS_SETUP_RESPONSE:
897 	case WLAN_TDLS_SETUP_CONFIRM:
898 	case WLAN_TDLS_TEARDOWN:
899 	case WLAN_TDLS_DISCOVERY_REQUEST:
900 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
901 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
902 		ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
903 						     sdata->dev, peer,
904 						     action_code, dialog_token,
905 						     status_code, skb);
906 		break;
907 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
908 		ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
909 						 peer, action_code,
910 						 dialog_token, status_code,
911 						 skb);
912 		break;
913 	default:
914 		ret = -ENOTSUPP;
915 		break;
916 	}
917 
918 	if (ret < 0)
919 		goto fail;
920 
921 	ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
922 			       initiator, extra_ies, extra_ies_len, oper_class,
923 			       chandef);
924 	return skb;
925 
926 fail:
927 	dev_kfree_skb(skb);
928 	return NULL;
929 }
930 
931 static int
932 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
933 				const u8 *peer, u8 action_code, u8 dialog_token,
934 				u16 status_code, u32 peer_capability,
935 				bool initiator, const u8 *extra_ies,
936 				size_t extra_ies_len, u8 oper_class,
937 				struct cfg80211_chan_def *chandef)
938 {
939 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
940 	struct sk_buff *skb = NULL;
941 	struct sta_info *sta;
942 	u32 flags = 0;
943 	int ret = 0;
944 
945 	rcu_read_lock();
946 	sta = sta_info_get(sdata, peer);
947 
948 	/* infer the initiator if we can, to support old userspace */
949 	switch (action_code) {
950 	case WLAN_TDLS_SETUP_REQUEST:
951 		if (sta) {
952 			set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
953 			sta->sta.tdls_initiator = false;
954 		}
955 		/* fall-through */
956 	case WLAN_TDLS_SETUP_CONFIRM:
957 	case WLAN_TDLS_DISCOVERY_REQUEST:
958 		initiator = true;
959 		break;
960 	case WLAN_TDLS_SETUP_RESPONSE:
961 		/*
962 		 * In some testing scenarios, we send a request and response.
963 		 * Make the last packet sent take effect for the initiator
964 		 * value.
965 		 */
966 		if (sta) {
967 			clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
968 			sta->sta.tdls_initiator = true;
969 		}
970 		/* fall-through */
971 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
972 		initiator = false;
973 		break;
974 	case WLAN_TDLS_TEARDOWN:
975 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
976 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
977 		/* any value is ok */
978 		break;
979 	default:
980 		ret = -ENOTSUPP;
981 		break;
982 	}
983 
984 	if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
985 		initiator = true;
986 
987 	rcu_read_unlock();
988 	if (ret < 0)
989 		goto fail;
990 
991 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
992 						    dialog_token, status_code,
993 						    initiator, extra_ies,
994 						    extra_ies_len, oper_class,
995 						    chandef);
996 	if (!skb) {
997 		ret = -EINVAL;
998 		goto fail;
999 	}
1000 
1001 	if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
1002 		ieee80211_tx_skb(sdata, skb);
1003 		return 0;
1004 	}
1005 
1006 	/*
1007 	 * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
1008 	 * we should default to AC_VI.
1009 	 */
1010 	switch (action_code) {
1011 	case WLAN_TDLS_SETUP_REQUEST:
1012 	case WLAN_TDLS_SETUP_RESPONSE:
1013 		skb_set_queue_mapping(skb, IEEE80211_AC_BK);
1014 		skb->priority = 2;
1015 		break;
1016 	default:
1017 		skb_set_queue_mapping(skb, IEEE80211_AC_VI);
1018 		skb->priority = 5;
1019 		break;
1020 	}
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);
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 	if (elems.parse_error) {
1721 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1722 		ret = -EINVAL;
1723 		goto out;
1724 	}
1725 
1726 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1727 		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1728 		ret = -EINVAL;
1729 		goto out;
1730 	}
1731 
1732 	/* validate the initiator is set correctly */
1733 	local_initiator =
1734 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1735 	if (local_initiator == sta->sta.tdls_initiator) {
1736 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1737 		ret = -EINVAL;
1738 		goto out;
1739 	}
1740 
1741 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1742 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1743 
1744 	params.tmpl_skb =
1745 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1746 	if (!params.tmpl_skb) {
1747 		ret = -ENOENT;
1748 		goto out;
1749 	}
1750 
1751 	ret = 0;
1752 call_drv:
1753 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1754 
1755 	tdls_dbg(sdata,
1756 		 "TDLS channel switch response received from %pM status %d\n",
1757 		 tf->sa, params.status);
1758 
1759 out:
1760 	mutex_unlock(&local->sta_mtx);
1761 	dev_kfree_skb_any(params.tmpl_skb);
1762 	return ret;
1763 }
1764 
1765 static int
1766 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1767 					  struct sk_buff *skb)
1768 {
1769 	struct ieee80211_local *local = sdata->local;
1770 	struct ieee802_11_elems elems;
1771 	struct cfg80211_chan_def chandef;
1772 	struct ieee80211_channel *chan;
1773 	enum nl80211_channel_type chan_type;
1774 	int freq;
1775 	u8 target_channel, oper_class;
1776 	bool local_initiator;
1777 	struct sta_info *sta;
1778 	enum nl80211_band band;
1779 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1780 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1781 	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1782 	struct ieee80211_tdls_ch_sw_params params = {};
1783 	int ret = 0;
1784 
1785 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1786 	params.timestamp = rx_status->device_timestamp;
1787 
1788 	if (skb->len < baselen) {
1789 		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1790 			 skb->len);
1791 		return -EINVAL;
1792 	}
1793 
1794 	target_channel = tf->u.chan_switch_req.target_channel;
1795 	oper_class = tf->u.chan_switch_req.oper_class;
1796 
1797 	/*
1798 	 * We can't easily infer the channel band. The operating class is
1799 	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1800 	 * solution here is to treat channels with number >14 as 5GHz ones,
1801 	 * and specifically check for the (oper_class, channel) combinations
1802 	 * where this doesn't hold. These are thankfully unique according to
1803 	 * IEEE802.11-2012.
1804 	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1805 	 * valid here.
1806 	 */
1807 	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1808 	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1809 	     target_channel < 14)
1810 		band = NL80211_BAND_5GHZ;
1811 	else
1812 		band = target_channel < 14 ? NL80211_BAND_2GHZ :
1813 					     NL80211_BAND_5GHZ;
1814 
1815 	freq = ieee80211_channel_to_frequency(target_channel, band);
1816 	if (freq == 0) {
1817 		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1818 			 target_channel);
1819 		return -EINVAL;
1820 	}
1821 
1822 	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1823 	if (!chan) {
1824 		tdls_dbg(sdata,
1825 			 "Unsupported channel for TDLS chan switch: %d\n",
1826 			 target_channel);
1827 		return -EINVAL;
1828 	}
1829 
1830 	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1831 			       skb->len - baselen, false, &elems);
1832 	if (elems.parse_error) {
1833 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1834 		return -EINVAL;
1835 	}
1836 
1837 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1838 		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1839 		return -EINVAL;
1840 	}
1841 
1842 	if (!elems.sec_chan_offs) {
1843 		chan_type = NL80211_CHAN_HT20;
1844 	} else {
1845 		switch (elems.sec_chan_offs->sec_chan_offs) {
1846 		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1847 			chan_type = NL80211_CHAN_HT40PLUS;
1848 			break;
1849 		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1850 			chan_type = NL80211_CHAN_HT40MINUS;
1851 			break;
1852 		default:
1853 			chan_type = NL80211_CHAN_HT20;
1854 			break;
1855 		}
1856 	}
1857 
1858 	cfg80211_chandef_create(&chandef, chan, chan_type);
1859 
1860 	/* we will be active on the TDLS link */
1861 	if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1862 					   sdata->wdev.iftype)) {
1863 		tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1864 		return -EINVAL;
1865 	}
1866 
1867 	mutex_lock(&local->sta_mtx);
1868 	sta = sta_info_get(sdata, tf->sa);
1869 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1870 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1871 			 tf->sa);
1872 		ret = -EINVAL;
1873 		goto out;
1874 	}
1875 
1876 	params.sta = &sta->sta;
1877 
1878 	/* validate the initiator is set correctly */
1879 	local_initiator =
1880 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1881 	if (local_initiator == sta->sta.tdls_initiator) {
1882 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1883 		ret = -EINVAL;
1884 		goto out;
1885 	}
1886 
1887 	/* peer should have known better */
1888 	if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1889 	    elems.sec_chan_offs->sec_chan_offs) {
1890 		tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1891 		ret = -ENOTSUPP;
1892 		goto out;
1893 	}
1894 
1895 	params.chandef = &chandef;
1896 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1897 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1898 
1899 	params.tmpl_skb =
1900 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1901 						   &params.ch_sw_tm_ie);
1902 	if (!params.tmpl_skb) {
1903 		ret = -ENOENT;
1904 		goto out;
1905 	}
1906 
1907 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1908 
1909 	tdls_dbg(sdata,
1910 		 "TDLS ch switch request received from %pM ch %d width %d\n",
1911 		 tf->sa, params.chandef->chan->center_freq,
1912 		 params.chandef->width);
1913 out:
1914 	mutex_unlock(&local->sta_mtx);
1915 	dev_kfree_skb_any(params.tmpl_skb);
1916 	return ret;
1917 }
1918 
1919 static void
1920 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1921 				      struct sk_buff *skb)
1922 {
1923 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1924 	struct wiphy *wiphy = sdata->local->hw.wiphy;
1925 
1926 	ASSERT_RTNL();
1927 
1928 	/* make sure the driver supports it */
1929 	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1930 		return;
1931 
1932 	/* we want to access the entire packet */
1933 	if (skb_linearize(skb))
1934 		return;
1935 	/*
1936 	 * The packet/size was already validated by mac80211 Rx path, only look
1937 	 * at the action type.
1938 	 */
1939 	switch (tf->action_code) {
1940 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1941 		ieee80211_process_tdls_channel_switch_req(sdata, skb);
1942 		break;
1943 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1944 		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1945 		break;
1946 	default:
1947 		WARN_ON_ONCE(1);
1948 		return;
1949 	}
1950 }
1951 
1952 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1953 {
1954 	struct sta_info *sta;
1955 	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1956 
1957 	rcu_read_lock();
1958 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1959 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1960 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1961 			continue;
1962 
1963 		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1964 					    NL80211_TDLS_TEARDOWN, reason,
1965 					    GFP_ATOMIC);
1966 	}
1967 	rcu_read_unlock();
1968 }
1969 
1970 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1971 {
1972 	struct ieee80211_local *local =
1973 		container_of(wk, struct ieee80211_local, tdls_chsw_work);
1974 	struct ieee80211_sub_if_data *sdata;
1975 	struct sk_buff *skb;
1976 	struct ieee80211_tdls_data *tf;
1977 
1978 	rtnl_lock();
1979 	while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1980 		tf = (struct ieee80211_tdls_data *)skb->data;
1981 		list_for_each_entry(sdata, &local->interfaces, list) {
1982 			if (!ieee80211_sdata_running(sdata) ||
1983 			    sdata->vif.type != NL80211_IFTYPE_STATION ||
1984 			    !ether_addr_equal(tf->da, sdata->vif.addr))
1985 				continue;
1986 
1987 			ieee80211_process_tdls_channel_switch(sdata, skb);
1988 			break;
1989 		}
1990 
1991 		kfree_skb(skb);
1992 	}
1993 	rtnl_unlock();
1994 }
1995