xref: /openbmc/linux/net/mac80211/tdls.c (revision 305c8388)
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 	u8 *pos = skb_put(skb, 4);
230 
231 	*pos++ = WLAN_EID_AID;
232 	*pos++ = 2; /* len */
233 	put_unaligned_le16(sdata->vif.bss_conf.aid, pos);
234 }
235 
236 /* translate numbering in the WMM parameter IE to the mac80211 notation */
237 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
238 {
239 	switch (ac) {
240 	default:
241 		WARN_ON_ONCE(1);
242 		/* fall through */
243 	case 0:
244 		return IEEE80211_AC_BE;
245 	case 1:
246 		return IEEE80211_AC_BK;
247 	case 2:
248 		return IEEE80211_AC_VI;
249 	case 3:
250 		return IEEE80211_AC_VO;
251 	}
252 }
253 
254 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
255 {
256 	u8 ret;
257 
258 	ret = aifsn & 0x0f;
259 	if (acm)
260 		ret |= 0x10;
261 	ret |= (aci << 5) & 0x60;
262 	return ret;
263 }
264 
265 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
266 {
267 	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
268 	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
269 }
270 
271 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
272 					    struct sk_buff *skb)
273 {
274 	struct ieee80211_wmm_param_ie *wmm;
275 	struct ieee80211_tx_queue_params *txq;
276 	int i;
277 
278 	wmm = skb_put_zero(skb, sizeof(*wmm));
279 
280 	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
281 	wmm->len = sizeof(*wmm) - 2;
282 
283 	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
284 	wmm->oui[1] = 0x50;
285 	wmm->oui[2] = 0xf2;
286 	wmm->oui_type = 2; /* WME */
287 	wmm->oui_subtype = 1; /* WME param */
288 	wmm->version = 1; /* WME ver */
289 	wmm->qos_info = 0; /* U-APSD not in use */
290 
291 	/*
292 	 * Use the EDCA parameters defined for the BSS, or default if the AP
293 	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
294 	 */
295 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
296 		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
297 		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
298 							       txq->acm, i);
299 		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
300 		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
301 	}
302 }
303 
304 static void
305 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
306 				   struct sta_info *sta)
307 {
308 	/* IEEE802.11ac-2013 Table E-4 */
309 	u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
310 	struct cfg80211_chan_def uc = sta->tdls_chandef;
311 	enum nl80211_chan_width max_width = ieee80211_sta_cap_chan_bw(sta);
312 	int i;
313 
314 	/* only support upgrading non-narrow channels up to 80Mhz */
315 	if (max_width == NL80211_CHAN_WIDTH_5 ||
316 	    max_width == NL80211_CHAN_WIDTH_10)
317 		return;
318 
319 	if (max_width > NL80211_CHAN_WIDTH_80)
320 		max_width = NL80211_CHAN_WIDTH_80;
321 
322 	if (uc.width >= max_width)
323 		return;
324 	/*
325 	 * Channel usage constrains in the IEEE802.11ac-2013 specification only
326 	 * allow expanding a 20MHz channel to 80MHz in a single way. In
327 	 * addition, there are no 40MHz allowed channels that are not part of
328 	 * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
329 	 */
330 	for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
331 		if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
332 			uc.center_freq1 = centers_80mhz[i];
333 			uc.center_freq2 = 0;
334 			uc.width = NL80211_CHAN_WIDTH_80;
335 			break;
336 		}
337 
338 	if (!uc.center_freq1)
339 		return;
340 
341 	/* proceed to downgrade the chandef until usable or the same as AP BW */
342 	while (uc.width > max_width ||
343 	       (uc.width > sta->tdls_chandef.width &&
344 		!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &uc,
345 					       sdata->wdev.iftype)))
346 		ieee80211_chandef_downgrade(&uc);
347 
348 	if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
349 		tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
350 			 sta->tdls_chandef.width, uc.width);
351 
352 		/*
353 		 * the station is not yet authorized when BW upgrade is done,
354 		 * locking is not required
355 		 */
356 		sta->tdls_chandef = uc;
357 	}
358 }
359 
360 static void
361 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
362 				   struct sk_buff *skb, const u8 *peer,
363 				   u8 action_code, bool initiator,
364 				   const u8 *extra_ies, size_t extra_ies_len)
365 {
366 	struct ieee80211_supported_band *sband;
367 	struct ieee80211_local *local = sdata->local;
368 	struct ieee80211_sta_ht_cap ht_cap;
369 	struct ieee80211_sta_vht_cap vht_cap;
370 	struct sta_info *sta = NULL;
371 	size_t offset = 0, noffset;
372 	u8 *pos;
373 
374 	sband = ieee80211_get_sband(sdata);
375 	if (!sband)
376 		return;
377 
378 	ieee80211_add_srates_ie(sdata, skb, false, sband->band);
379 	ieee80211_add_ext_srates_ie(sdata, skb, false, sband->band);
380 	ieee80211_tdls_add_supp_channels(sdata, skb);
381 
382 	/* add any custom IEs that go before Extended Capabilities */
383 	if (extra_ies_len) {
384 		static const u8 before_ext_cap[] = {
385 			WLAN_EID_SUPP_RATES,
386 			WLAN_EID_COUNTRY,
387 			WLAN_EID_EXT_SUPP_RATES,
388 			WLAN_EID_SUPPORTED_CHANNELS,
389 			WLAN_EID_RSN,
390 		};
391 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
392 					     before_ext_cap,
393 					     ARRAY_SIZE(before_ext_cap),
394 					     offset);
395 		skb_put_data(skb, extra_ies + offset, noffset - offset);
396 		offset = noffset;
397 	}
398 
399 	ieee80211_tdls_add_ext_capab(sdata, skb);
400 
401 	/* add the QoS element if we support it */
402 	if (local->hw.queues >= IEEE80211_NUM_ACS &&
403 	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
404 		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
405 
406 	/* add any custom IEs that go before HT capabilities */
407 	if (extra_ies_len) {
408 		static const u8 before_ht_cap[] = {
409 			WLAN_EID_SUPP_RATES,
410 			WLAN_EID_COUNTRY,
411 			WLAN_EID_EXT_SUPP_RATES,
412 			WLAN_EID_SUPPORTED_CHANNELS,
413 			WLAN_EID_RSN,
414 			WLAN_EID_EXT_CAPABILITY,
415 			WLAN_EID_QOS_CAPA,
416 			WLAN_EID_FAST_BSS_TRANSITION,
417 			WLAN_EID_TIMEOUT_INTERVAL,
418 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
419 		};
420 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
421 					     before_ht_cap,
422 					     ARRAY_SIZE(before_ht_cap),
423 					     offset);
424 		skb_put_data(skb, extra_ies + offset, noffset - offset);
425 		offset = noffset;
426 	}
427 
428 	mutex_lock(&local->sta_mtx);
429 
430 	/* we should have the peer STA if we're already responding */
431 	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
432 		sta = sta_info_get(sdata, peer);
433 		if (WARN_ON_ONCE(!sta)) {
434 			mutex_unlock(&local->sta_mtx);
435 			return;
436 		}
437 
438 		sta->tdls_chandef = sdata->vif.bss_conf.chandef;
439 	}
440 
441 	ieee80211_tdls_add_oper_classes(sdata, skb);
442 
443 	/*
444 	 * with TDLS we can switch channels, and HT-caps are not necessarily
445 	 * the same on all bands. The specification limits the setup to a
446 	 * single HT-cap, so use the current band for now.
447 	 */
448 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
449 
450 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
451 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
452 	    ht_cap.ht_supported) {
453 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
454 
455 		/* disable SMPS in TDLS initiator */
456 		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
457 				<< IEEE80211_HT_CAP_SM_PS_SHIFT;
458 
459 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
460 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
461 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
462 		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
463 		/* the peer caps are already intersected with our own */
464 		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
465 
466 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
467 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
468 	}
469 
470 	if (ht_cap.ht_supported &&
471 	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
472 		ieee80211_tdls_add_bss_coex_ie(skb);
473 
474 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
475 
476 	/* add any custom IEs that go before VHT capabilities */
477 	if (extra_ies_len) {
478 		static const u8 before_vht_cap[] = {
479 			WLAN_EID_SUPP_RATES,
480 			WLAN_EID_COUNTRY,
481 			WLAN_EID_EXT_SUPP_RATES,
482 			WLAN_EID_SUPPORTED_CHANNELS,
483 			WLAN_EID_RSN,
484 			WLAN_EID_EXT_CAPABILITY,
485 			WLAN_EID_QOS_CAPA,
486 			WLAN_EID_FAST_BSS_TRANSITION,
487 			WLAN_EID_TIMEOUT_INTERVAL,
488 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
489 			WLAN_EID_MULTI_BAND,
490 		};
491 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
492 					     before_vht_cap,
493 					     ARRAY_SIZE(before_vht_cap),
494 					     offset);
495 		skb_put_data(skb, extra_ies + offset, noffset - offset);
496 		offset = noffset;
497 	}
498 
499 	/* build the VHT-cap similarly to the HT-cap */
500 	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
501 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
502 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
503 	    vht_cap.vht_supported) {
504 		ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
505 
506 		/* the AID is present only when VHT is implemented */
507 		if (action_code == WLAN_TDLS_SETUP_REQUEST)
508 			ieee80211_tdls_add_aid(sdata, skb);
509 
510 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
511 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
512 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
513 		   vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
514 		/* the peer caps are already intersected with our own */
515 		memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
516 
517 		/* the AID is present only when VHT is implemented */
518 		ieee80211_tdls_add_aid(sdata, skb);
519 
520 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
521 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
522 
523 		/*
524 		 * if both peers support WIDER_BW, we can expand the chandef to
525 		 * a wider compatible one, up to 80MHz
526 		 */
527 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
528 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
529 	}
530 
531 	mutex_unlock(&local->sta_mtx);
532 
533 	/* add any remaining IEs */
534 	if (extra_ies_len) {
535 		noffset = extra_ies_len;
536 		skb_put_data(skb, extra_ies + offset, noffset - offset);
537 	}
538 
539 }
540 
541 static void
542 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
543 				 struct sk_buff *skb, const u8 *peer,
544 				 bool initiator, const u8 *extra_ies,
545 				 size_t extra_ies_len)
546 {
547 	struct ieee80211_local *local = sdata->local;
548 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
549 	size_t offset = 0, noffset;
550 	struct sta_info *sta, *ap_sta;
551 	struct ieee80211_supported_band *sband;
552 	u8 *pos;
553 
554 	sband = ieee80211_get_sband(sdata);
555 	if (!sband)
556 		return;
557 
558 	mutex_lock(&local->sta_mtx);
559 
560 	sta = sta_info_get(sdata, peer);
561 	ap_sta = sta_info_get(sdata, ifmgd->bssid);
562 	if (WARN_ON_ONCE(!sta || !ap_sta)) {
563 		mutex_unlock(&local->sta_mtx);
564 		return;
565 	}
566 
567 	sta->tdls_chandef = sdata->vif.bss_conf.chandef;
568 
569 	/* add any custom IEs that go before the QoS IE */
570 	if (extra_ies_len) {
571 		static const u8 before_qos[] = {
572 			WLAN_EID_RSN,
573 		};
574 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
575 					     before_qos,
576 					     ARRAY_SIZE(before_qos),
577 					     offset);
578 		skb_put_data(skb, extra_ies + offset, noffset - offset);
579 		offset = noffset;
580 	}
581 
582 	/* add the QoS param IE if both the peer and we support it */
583 	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
584 		ieee80211_tdls_add_wmm_param_ie(sdata, skb);
585 
586 	/* add any custom IEs that go before HT operation */
587 	if (extra_ies_len) {
588 		static const u8 before_ht_op[] = {
589 			WLAN_EID_RSN,
590 			WLAN_EID_QOS_CAPA,
591 			WLAN_EID_FAST_BSS_TRANSITION,
592 			WLAN_EID_TIMEOUT_INTERVAL,
593 		};
594 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
595 					     before_ht_op,
596 					     ARRAY_SIZE(before_ht_op),
597 					     offset);
598 		skb_put_data(skb, extra_ies + offset, noffset - offset);
599 		offset = noffset;
600 	}
601 
602 	/*
603 	 * if HT support is only added in TDLS, we need an HT-operation IE.
604 	 * add the IE as required by IEEE802.11-2012 9.23.3.2.
605 	 */
606 	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
607 		u16 prot = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
608 			   IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
609 			   IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
610 
611 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
612 		ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
613 					   &sdata->vif.bss_conf.chandef, prot,
614 					   true);
615 	}
616 
617 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
618 
619 	/* only include VHT-operation if not on the 2.4GHz band */
620 	if (sband->band != NL80211_BAND_2GHZ &&
621 	    sta->sta.vht_cap.vht_supported) {
622 		/*
623 		 * if both peers support WIDER_BW, we can expand the chandef to
624 		 * a wider compatible one, up to 80MHz
625 		 */
626 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
627 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
628 
629 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
630 		ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
631 					    &sta->tdls_chandef);
632 	}
633 
634 	mutex_unlock(&local->sta_mtx);
635 
636 	/* add any remaining IEs */
637 	if (extra_ies_len) {
638 		noffset = extra_ies_len;
639 		skb_put_data(skb, extra_ies + offset, noffset - offset);
640 	}
641 }
642 
643 static void
644 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
645 				       struct sk_buff *skb, const u8 *peer,
646 				       bool initiator, const u8 *extra_ies,
647 				       size_t extra_ies_len, u8 oper_class,
648 				       struct cfg80211_chan_def *chandef)
649 {
650 	struct ieee80211_tdls_data *tf;
651 	size_t offset = 0, noffset;
652 
653 	if (WARN_ON_ONCE(!chandef))
654 		return;
655 
656 	tf = (void *)skb->data;
657 	tf->u.chan_switch_req.target_channel =
658 		ieee80211_frequency_to_channel(chandef->chan->center_freq);
659 	tf->u.chan_switch_req.oper_class = oper_class;
660 
661 	if (extra_ies_len) {
662 		static const u8 before_lnkie[] = {
663 			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
664 		};
665 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
666 					     before_lnkie,
667 					     ARRAY_SIZE(before_lnkie),
668 					     offset);
669 		skb_put_data(skb, extra_ies + offset, noffset - offset);
670 		offset = noffset;
671 	}
672 
673 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
674 
675 	/* add any remaining IEs */
676 	if (extra_ies_len) {
677 		noffset = extra_ies_len;
678 		skb_put_data(skb, extra_ies + offset, noffset - offset);
679 	}
680 }
681 
682 static void
683 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
684 					struct sk_buff *skb, const u8 *peer,
685 					u16 status_code, bool initiator,
686 					const u8 *extra_ies,
687 					size_t extra_ies_len)
688 {
689 	if (status_code == 0)
690 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
691 
692 	if (extra_ies_len)
693 		skb_put_data(skb, extra_ies, extra_ies_len);
694 }
695 
696 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
697 				   struct sk_buff *skb, const u8 *peer,
698 				   u8 action_code, u16 status_code,
699 				   bool initiator, const u8 *extra_ies,
700 				   size_t extra_ies_len, u8 oper_class,
701 				   struct cfg80211_chan_def *chandef)
702 {
703 	switch (action_code) {
704 	case WLAN_TDLS_SETUP_REQUEST:
705 	case WLAN_TDLS_SETUP_RESPONSE:
706 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
707 		if (status_code == 0)
708 			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
709 							   action_code,
710 							   initiator,
711 							   extra_ies,
712 							   extra_ies_len);
713 		break;
714 	case WLAN_TDLS_SETUP_CONFIRM:
715 		if (status_code == 0)
716 			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
717 							 initiator, extra_ies,
718 							 extra_ies_len);
719 		break;
720 	case WLAN_TDLS_TEARDOWN:
721 	case WLAN_TDLS_DISCOVERY_REQUEST:
722 		if (extra_ies_len)
723 			skb_put_data(skb, extra_ies, extra_ies_len);
724 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
725 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
726 		break;
727 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
728 		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
729 						       initiator, extra_ies,
730 						       extra_ies_len,
731 						       oper_class, chandef);
732 		break;
733 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
734 		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
735 							status_code,
736 							initiator, extra_ies,
737 							extra_ies_len);
738 		break;
739 	}
740 
741 }
742 
743 static int
744 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
745 			       const u8 *peer, u8 action_code, u8 dialog_token,
746 			       u16 status_code, struct sk_buff *skb)
747 {
748 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
749 	struct ieee80211_tdls_data *tf;
750 
751 	tf = skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
752 
753 	memcpy(tf->da, peer, ETH_ALEN);
754 	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
755 	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
756 	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
757 
758 	/* network header is after the ethernet header */
759 	skb_set_network_header(skb, ETH_HLEN);
760 
761 	switch (action_code) {
762 	case WLAN_TDLS_SETUP_REQUEST:
763 		tf->category = WLAN_CATEGORY_TDLS;
764 		tf->action_code = WLAN_TDLS_SETUP_REQUEST;
765 
766 		skb_put(skb, sizeof(tf->u.setup_req));
767 		tf->u.setup_req.dialog_token = dialog_token;
768 		tf->u.setup_req.capability =
769 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
770 								 status_code));
771 		break;
772 	case WLAN_TDLS_SETUP_RESPONSE:
773 		tf->category = WLAN_CATEGORY_TDLS;
774 		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
775 
776 		skb_put(skb, sizeof(tf->u.setup_resp));
777 		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
778 		tf->u.setup_resp.dialog_token = dialog_token;
779 		tf->u.setup_resp.capability =
780 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
781 								 status_code));
782 		break;
783 	case WLAN_TDLS_SETUP_CONFIRM:
784 		tf->category = WLAN_CATEGORY_TDLS;
785 		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
786 
787 		skb_put(skb, sizeof(tf->u.setup_cfm));
788 		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
789 		tf->u.setup_cfm.dialog_token = dialog_token;
790 		break;
791 	case WLAN_TDLS_TEARDOWN:
792 		tf->category = WLAN_CATEGORY_TDLS;
793 		tf->action_code = WLAN_TDLS_TEARDOWN;
794 
795 		skb_put(skb, sizeof(tf->u.teardown));
796 		tf->u.teardown.reason_code = cpu_to_le16(status_code);
797 		break;
798 	case WLAN_TDLS_DISCOVERY_REQUEST:
799 		tf->category = WLAN_CATEGORY_TDLS;
800 		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
801 
802 		skb_put(skb, sizeof(tf->u.discover_req));
803 		tf->u.discover_req.dialog_token = dialog_token;
804 		break;
805 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
806 		tf->category = WLAN_CATEGORY_TDLS;
807 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
808 
809 		skb_put(skb, sizeof(tf->u.chan_switch_req));
810 		break;
811 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
812 		tf->category = WLAN_CATEGORY_TDLS;
813 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
814 
815 		skb_put(skb, sizeof(tf->u.chan_switch_resp));
816 		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
817 		break;
818 	default:
819 		return -EINVAL;
820 	}
821 
822 	return 0;
823 }
824 
825 static int
826 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
827 			   const u8 *peer, u8 action_code, u8 dialog_token,
828 			   u16 status_code, struct sk_buff *skb)
829 {
830 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
831 	struct ieee80211_mgmt *mgmt;
832 
833 	mgmt = skb_put_zero(skb, 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->priority = 256 + 2;
1014 		break;
1015 	default:
1016 		skb->priority = 256 + 5;
1017 		break;
1018 	}
1019 	skb_set_queue_mapping(skb, ieee80211_select_queue(sdata, skb));
1020 
1021 	/*
1022 	 * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
1023 	 * Later, if no ACK is returned from peer, we will re-send the teardown
1024 	 * packet through the AP.
1025 	 */
1026 	if ((action_code == WLAN_TDLS_TEARDOWN) &&
1027 	    ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
1028 		bool try_resend; /* Should we keep skb for possible resend */
1029 
1030 		/* If not sending directly to peer - no point in keeping skb */
1031 		rcu_read_lock();
1032 		sta = sta_info_get(sdata, peer);
1033 		try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1034 		rcu_read_unlock();
1035 
1036 		spin_lock_bh(&sdata->u.mgd.teardown_lock);
1037 		if (try_resend && !sdata->u.mgd.teardown_skb) {
1038 			/* Mark it as requiring TX status callback  */
1039 			flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
1040 				 IEEE80211_TX_INTFL_MLME_CONN_TX;
1041 
1042 			/*
1043 			 * skb is copied since mac80211 will later set
1044 			 * properties that might not be the same as the AP,
1045 			 * such as encryption, QoS, addresses, etc.
1046 			 *
1047 			 * No problem if skb_copy() fails, so no need to check.
1048 			 */
1049 			sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
1050 			sdata->u.mgd.orig_teardown_skb = skb;
1051 		}
1052 		spin_unlock_bh(&sdata->u.mgd.teardown_lock);
1053 	}
1054 
1055 	/* disable bottom halves when entering the Tx path */
1056 	local_bh_disable();
1057 	__ieee80211_subif_start_xmit(skb, dev, flags, 0, NULL);
1058 	local_bh_enable();
1059 
1060 	return ret;
1061 
1062 fail:
1063 	dev_kfree_skb(skb);
1064 	return ret;
1065 }
1066 
1067 static int
1068 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
1069 			  const u8 *peer, u8 action_code, u8 dialog_token,
1070 			  u16 status_code, u32 peer_capability, bool initiator,
1071 			  const u8 *extra_ies, size_t extra_ies_len)
1072 {
1073 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1074 	struct ieee80211_local *local = sdata->local;
1075 	enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
1076 	int ret;
1077 
1078 	/* don't support setup with forced SMPS mode that's not off */
1079 	if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
1080 	    smps_mode != IEEE80211_SMPS_OFF) {
1081 		tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
1082 			 smps_mode);
1083 		return -ENOTSUPP;
1084 	}
1085 
1086 	mutex_lock(&local->mtx);
1087 
1088 	/* we don't support concurrent TDLS peer setups */
1089 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
1090 	    !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1091 		ret = -EBUSY;
1092 		goto out_unlock;
1093 	}
1094 
1095 	/*
1096 	 * make sure we have a STA representing the peer so we drop or buffer
1097 	 * non-TDLS-setup frames to the peer. We can't send other packets
1098 	 * during setup through the AP path.
1099 	 * Allow error packets to be sent - sometimes we don't even add a STA
1100 	 * before failing the setup.
1101 	 */
1102 	if (status_code == 0) {
1103 		rcu_read_lock();
1104 		if (!sta_info_get(sdata, peer)) {
1105 			rcu_read_unlock();
1106 			ret = -ENOLINK;
1107 			goto out_unlock;
1108 		}
1109 		rcu_read_unlock();
1110 	}
1111 
1112 	ieee80211_flush_queues(local, sdata, false);
1113 	memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
1114 	mutex_unlock(&local->mtx);
1115 
1116 	/* we cannot take the mutex while preparing the setup packet */
1117 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1118 					      dialog_token, status_code,
1119 					      peer_capability, initiator,
1120 					      extra_ies, extra_ies_len, 0,
1121 					      NULL);
1122 	if (ret < 0) {
1123 		mutex_lock(&local->mtx);
1124 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1125 		mutex_unlock(&local->mtx);
1126 		return ret;
1127 	}
1128 
1129 	ieee80211_queue_delayed_work(&sdata->local->hw,
1130 				     &sdata->u.mgd.tdls_peer_del_work,
1131 				     TDLS_PEER_SETUP_TIMEOUT);
1132 	return 0;
1133 
1134 out_unlock:
1135 	mutex_unlock(&local->mtx);
1136 	return ret;
1137 }
1138 
1139 static int
1140 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
1141 			     const u8 *peer, u8 action_code, u8 dialog_token,
1142 			     u16 status_code, u32 peer_capability,
1143 			     bool initiator, const u8 *extra_ies,
1144 			     size_t extra_ies_len)
1145 {
1146 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1147 	struct ieee80211_local *local = sdata->local;
1148 	struct sta_info *sta;
1149 	int ret;
1150 
1151 	/*
1152 	 * No packets can be transmitted to the peer via the AP during setup -
1153 	 * the STA is set as a TDLS peer, but is not authorized.
1154 	 * During teardown, we prevent direct transmissions by stopping the
1155 	 * queues and flushing all direct packets.
1156 	 */
1157 	ieee80211_stop_vif_queues(local, sdata,
1158 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1159 	ieee80211_flush_queues(local, sdata, false);
1160 
1161 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1162 					      dialog_token, status_code,
1163 					      peer_capability, initiator,
1164 					      extra_ies, extra_ies_len, 0,
1165 					      NULL);
1166 	if (ret < 0)
1167 		sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
1168 			  ret);
1169 
1170 	/*
1171 	 * Remove the STA AUTH flag to force further traffic through the AP. If
1172 	 * the STA was unreachable, it was already removed.
1173 	 */
1174 	rcu_read_lock();
1175 	sta = sta_info_get(sdata, peer);
1176 	if (sta)
1177 		clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1178 	rcu_read_unlock();
1179 
1180 	ieee80211_wake_vif_queues(local, sdata,
1181 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1182 
1183 	return 0;
1184 }
1185 
1186 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
1187 			const u8 *peer, u8 action_code, u8 dialog_token,
1188 			u16 status_code, u32 peer_capability,
1189 			bool initiator, const u8 *extra_ies,
1190 			size_t extra_ies_len)
1191 {
1192 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1193 	int ret;
1194 
1195 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1196 		return -ENOTSUPP;
1197 
1198 	/* make sure we are in managed mode, and associated */
1199 	if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1200 	    !sdata->u.mgd.associated)
1201 		return -EINVAL;
1202 
1203 	switch (action_code) {
1204 	case WLAN_TDLS_SETUP_REQUEST:
1205 	case WLAN_TDLS_SETUP_RESPONSE:
1206 		ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1207 						dialog_token, status_code,
1208 						peer_capability, initiator,
1209 						extra_ies, extra_ies_len);
1210 		break;
1211 	case WLAN_TDLS_TEARDOWN:
1212 		ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1213 						   action_code, dialog_token,
1214 						   status_code,
1215 						   peer_capability, initiator,
1216 						   extra_ies, extra_ies_len);
1217 		break;
1218 	case WLAN_TDLS_DISCOVERY_REQUEST:
1219 		/*
1220 		 * Protect the discovery so we can hear the TDLS discovery
1221 		 * response frame. It is transmitted directly and not buffered
1222 		 * by the AP.
1223 		 */
1224 		drv_mgd_protect_tdls_discover(sdata->local, sdata);
1225 		/* fall-through */
1226 	case WLAN_TDLS_SETUP_CONFIRM:
1227 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1228 		/* no special handling */
1229 		ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1230 						      action_code,
1231 						      dialog_token,
1232 						      status_code,
1233 						      peer_capability,
1234 						      initiator, extra_ies,
1235 						      extra_ies_len, 0, NULL);
1236 		break;
1237 	default:
1238 		ret = -EOPNOTSUPP;
1239 		break;
1240 	}
1241 
1242 	tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1243 		 action_code, peer, ret);
1244 	return ret;
1245 }
1246 
1247 static void iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data *sdata,
1248 					 struct sta_info *sta)
1249 {
1250 	struct ieee80211_local *local = sdata->local;
1251 	struct ieee80211_chanctx_conf *conf;
1252 	struct ieee80211_chanctx *ctx;
1253 	enum nl80211_chan_width width;
1254 	struct ieee80211_supported_band *sband;
1255 
1256 	mutex_lock(&local->chanctx_mtx);
1257 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1258 					 lockdep_is_held(&local->chanctx_mtx));
1259 	if (conf) {
1260 		width = conf->def.width;
1261 		sband = local->hw.wiphy->bands[conf->def.chan->band];
1262 		ctx = container_of(conf, struct ieee80211_chanctx, conf);
1263 		ieee80211_recalc_chanctx_chantype(local, ctx);
1264 
1265 		/* if width changed and a peer is given, update its BW */
1266 		if (width != conf->def.width && sta &&
1267 		    test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW)) {
1268 			enum ieee80211_sta_rx_bandwidth bw;
1269 
1270 			bw = ieee80211_chan_width_to_rx_bw(conf->def.width);
1271 			bw = min(bw, ieee80211_sta_cap_rx_bw(sta));
1272 			if (bw != sta->sta.bandwidth) {
1273 				sta->sta.bandwidth = bw;
1274 				rate_control_rate_update(local, sband, sta,
1275 							 IEEE80211_RC_BW_CHANGED);
1276 				/*
1277 				 * if a TDLS peer BW was updated, we need to
1278 				 * recalc the chandef width again, to get the
1279 				 * correct chanctx min_def
1280 				 */
1281 				ieee80211_recalc_chanctx_chantype(local, ctx);
1282 			}
1283 		}
1284 
1285 	}
1286 	mutex_unlock(&local->chanctx_mtx);
1287 }
1288 
1289 static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
1290 {
1291 	struct sta_info *sta;
1292 	bool result = false;
1293 
1294 	rcu_read_lock();
1295 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1296 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1297 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
1298 		    !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
1299 		    !sta->sta.ht_cap.ht_supported)
1300 			continue;
1301 		result = true;
1302 		break;
1303 	}
1304 	rcu_read_unlock();
1305 
1306 	return result;
1307 }
1308 
1309 static void
1310 iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
1311 				   struct sta_info *sta)
1312 {
1313 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
1314 	bool tdls_ht;
1315 	u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
1316 			 IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
1317 			 IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
1318 	u16 opmode;
1319 
1320 	/* Nothing to do if the BSS connection uses HT */
1321 	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
1322 		return;
1323 
1324 	tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
1325 		  iee80211_tdls_have_ht_peers(sdata);
1326 
1327 	opmode = sdata->vif.bss_conf.ht_operation_mode;
1328 
1329 	if (tdls_ht)
1330 		opmode |= protection;
1331 	else
1332 		opmode &= ~protection;
1333 
1334 	if (opmode == sdata->vif.bss_conf.ht_operation_mode)
1335 		return;
1336 
1337 	sdata->vif.bss_conf.ht_operation_mode = opmode;
1338 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
1339 }
1340 
1341 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1342 			const u8 *peer, enum nl80211_tdls_operation oper)
1343 {
1344 	struct sta_info *sta;
1345 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1346 	struct ieee80211_local *local = sdata->local;
1347 	int ret;
1348 
1349 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1350 		return -ENOTSUPP;
1351 
1352 	if (sdata->vif.type != NL80211_IFTYPE_STATION)
1353 		return -EINVAL;
1354 
1355 	switch (oper) {
1356 	case NL80211_TDLS_ENABLE_LINK:
1357 	case NL80211_TDLS_DISABLE_LINK:
1358 		break;
1359 	case NL80211_TDLS_TEARDOWN:
1360 	case NL80211_TDLS_SETUP:
1361 	case NL80211_TDLS_DISCOVERY_REQ:
1362 		/* We don't support in-driver setup/teardown/discovery */
1363 		return -ENOTSUPP;
1364 	}
1365 
1366 	/* protect possible bss_conf changes and avoid concurrency in
1367 	 * ieee80211_bss_info_change_notify()
1368 	 */
1369 	sdata_lock(sdata);
1370 	mutex_lock(&local->mtx);
1371 	tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1372 
1373 	switch (oper) {
1374 	case NL80211_TDLS_ENABLE_LINK:
1375 		if (sdata->vif.csa_active) {
1376 			tdls_dbg(sdata, "TDLS: disallow link during CSA\n");
1377 			ret = -EBUSY;
1378 			break;
1379 		}
1380 
1381 		mutex_lock(&local->sta_mtx);
1382 		sta = sta_info_get(sdata, peer);
1383 		if (!sta) {
1384 			mutex_unlock(&local->sta_mtx);
1385 			ret = -ENOLINK;
1386 			break;
1387 		}
1388 
1389 		iee80211_tdls_recalc_chanctx(sdata, sta);
1390 		iee80211_tdls_recalc_ht_protection(sdata, sta);
1391 
1392 		set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1393 		mutex_unlock(&local->sta_mtx);
1394 
1395 		WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1396 			     !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1397 		ret = 0;
1398 		break;
1399 	case NL80211_TDLS_DISABLE_LINK:
1400 		/*
1401 		 * The teardown message in ieee80211_tdls_mgmt_teardown() was
1402 		 * created while the queues were stopped, so it might still be
1403 		 * pending. Before flushing the queues we need to be sure the
1404 		 * message is handled by the tasklet handling pending messages,
1405 		 * otherwise we might start destroying the station before
1406 		 * sending the teardown packet.
1407 		 * Note that this only forces the tasklet to flush pendings -
1408 		 * not to stop the tasklet from rescheduling itself.
1409 		 */
1410 		tasklet_kill(&local->tx_pending_tasklet);
1411 		/* flush a potentially queued teardown packet */
1412 		ieee80211_flush_queues(local, sdata, false);
1413 
1414 		ret = sta_info_destroy_addr(sdata, peer);
1415 
1416 		mutex_lock(&local->sta_mtx);
1417 		iee80211_tdls_recalc_ht_protection(sdata, NULL);
1418 		mutex_unlock(&local->sta_mtx);
1419 
1420 		iee80211_tdls_recalc_chanctx(sdata, NULL);
1421 		break;
1422 	default:
1423 		ret = -ENOTSUPP;
1424 		break;
1425 	}
1426 
1427 	if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1428 		cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1429 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1430 	}
1431 
1432 	if (ret == 0)
1433 		ieee80211_queue_work(&sdata->local->hw,
1434 				     &sdata->u.mgd.request_smps_work);
1435 
1436 	mutex_unlock(&local->mtx);
1437 	sdata_unlock(sdata);
1438 	return ret;
1439 }
1440 
1441 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1442 				 enum nl80211_tdls_operation oper,
1443 				 u16 reason_code, gfp_t gfp)
1444 {
1445 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1446 
1447 	if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1448 		sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1449 			  oper);
1450 		return;
1451 	}
1452 
1453 	cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1454 }
1455 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1456 
1457 static void
1458 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1459 {
1460 	struct ieee80211_ch_switch_timing *ch_sw;
1461 
1462 	*buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1463 	*buf++ = sizeof(struct ieee80211_ch_switch_timing);
1464 
1465 	ch_sw = (void *)buf;
1466 	ch_sw->switch_time = cpu_to_le16(switch_time);
1467 	ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1468 }
1469 
1470 /* find switch timing IE in SKB ready for Tx */
1471 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1472 {
1473 	struct ieee80211_tdls_data *tf;
1474 	const u8 *ie_start;
1475 
1476 	/*
1477 	 * Get the offset for the new location of the switch timing IE.
1478 	 * The SKB network header will now point to the "payload_type"
1479 	 * element of the TDLS data frame struct.
1480 	 */
1481 	tf = container_of(skb->data + skb_network_offset(skb),
1482 			  struct ieee80211_tdls_data, payload_type);
1483 	ie_start = tf->u.chan_switch_req.variable;
1484 	return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1485 				skb->len - (ie_start - skb->data));
1486 }
1487 
1488 static struct sk_buff *
1489 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1490 			      struct cfg80211_chan_def *chandef,
1491 			      u32 *ch_sw_tm_ie_offset)
1492 {
1493 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1494 	u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1495 		     2 + sizeof(struct ieee80211_ch_switch_timing)];
1496 	int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1497 	u8 *pos = extra_ies;
1498 	struct sk_buff *skb;
1499 
1500 	/*
1501 	 * if chandef points to a wide channel add a Secondary-Channel
1502 	 * Offset information element
1503 	 */
1504 	if (chandef->width == NL80211_CHAN_WIDTH_40) {
1505 		struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1506 		bool ht40plus;
1507 
1508 		*pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1509 		*pos++ = sizeof(*sec_chan_ie);
1510 		sec_chan_ie = (void *)pos;
1511 
1512 		ht40plus = cfg80211_get_chandef_type(chandef) ==
1513 							NL80211_CHAN_HT40PLUS;
1514 		sec_chan_ie->sec_chan_offs = ht40plus ?
1515 					     IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1516 					     IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1517 		pos += sizeof(*sec_chan_ie);
1518 
1519 		extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1520 	}
1521 
1522 	/* just set the values to 0, this is a template */
1523 	iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1524 
1525 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1526 					      WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1527 					      0, 0, !sta->sta.tdls_initiator,
1528 					      extra_ies, extra_ies_len,
1529 					      oper_class, chandef);
1530 	if (!skb)
1531 		return NULL;
1532 
1533 	skb = ieee80211_build_data_template(sdata, skb, 0);
1534 	if (IS_ERR(skb)) {
1535 		tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1536 		return NULL;
1537 	}
1538 
1539 	if (ch_sw_tm_ie_offset) {
1540 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1541 
1542 		if (!tm_ie) {
1543 			tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1544 			dev_kfree_skb_any(skb);
1545 			return NULL;
1546 		}
1547 
1548 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1549 	}
1550 
1551 	tdls_dbg(sdata,
1552 		 "TDLS channel switch request template for %pM ch %d width %d\n",
1553 		 sta->sta.addr, chandef->chan->center_freq, chandef->width);
1554 	return skb;
1555 }
1556 
1557 int
1558 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1559 			      const u8 *addr, u8 oper_class,
1560 			      struct cfg80211_chan_def *chandef)
1561 {
1562 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1563 	struct ieee80211_local *local = sdata->local;
1564 	struct sta_info *sta;
1565 	struct sk_buff *skb = NULL;
1566 	u32 ch_sw_tm_ie;
1567 	int ret;
1568 
1569 	if (chandef->chan->freq_offset)
1570 		/* this may work, but is untested */
1571 		return -EOPNOTSUPP;
1572 
1573 	mutex_lock(&local->sta_mtx);
1574 	sta = sta_info_get(sdata, addr);
1575 	if (!sta) {
1576 		tdls_dbg(sdata,
1577 			 "Invalid TDLS peer %pM for channel switch request\n",
1578 			 addr);
1579 		ret = -ENOENT;
1580 		goto out;
1581 	}
1582 
1583 	if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1584 		tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1585 			 addr);
1586 		ret = -ENOTSUPP;
1587 		goto out;
1588 	}
1589 
1590 	skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1591 					    &ch_sw_tm_ie);
1592 	if (!skb) {
1593 		ret = -ENOENT;
1594 		goto out;
1595 	}
1596 
1597 	ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1598 				      chandef, skb, ch_sw_tm_ie);
1599 	if (!ret)
1600 		set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1601 
1602 out:
1603 	mutex_unlock(&local->sta_mtx);
1604 	dev_kfree_skb_any(skb);
1605 	return ret;
1606 }
1607 
1608 void
1609 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1610 				     struct net_device *dev,
1611 				     const u8 *addr)
1612 {
1613 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1614 	struct ieee80211_local *local = sdata->local;
1615 	struct sta_info *sta;
1616 
1617 	mutex_lock(&local->sta_mtx);
1618 	sta = sta_info_get(sdata, addr);
1619 	if (!sta) {
1620 		tdls_dbg(sdata,
1621 			 "Invalid TDLS peer %pM for channel switch cancel\n",
1622 			 addr);
1623 		goto out;
1624 	}
1625 
1626 	if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1627 		tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1628 			 addr);
1629 		goto out;
1630 	}
1631 
1632 	drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1633 	clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1634 
1635 out:
1636 	mutex_unlock(&local->sta_mtx);
1637 }
1638 
1639 static struct sk_buff *
1640 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1641 				   u32 *ch_sw_tm_ie_offset)
1642 {
1643 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1644 	struct sk_buff *skb;
1645 	u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1646 
1647 	/* initial timing are always zero in the template */
1648 	iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1649 
1650 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1651 					WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1652 					0, 0, !sta->sta.tdls_initiator,
1653 					extra_ies, sizeof(extra_ies), 0, NULL);
1654 	if (!skb)
1655 		return NULL;
1656 
1657 	skb = ieee80211_build_data_template(sdata, skb, 0);
1658 	if (IS_ERR(skb)) {
1659 		tdls_dbg(sdata,
1660 			 "Failed building TDLS channel switch resp frame\n");
1661 		return NULL;
1662 	}
1663 
1664 	if (ch_sw_tm_ie_offset) {
1665 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1666 
1667 		if (!tm_ie) {
1668 			tdls_dbg(sdata,
1669 				 "No switch timing IE in TDLS switch resp\n");
1670 			dev_kfree_skb_any(skb);
1671 			return NULL;
1672 		}
1673 
1674 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1675 	}
1676 
1677 	tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1678 		 sta->sta.addr);
1679 	return skb;
1680 }
1681 
1682 static int
1683 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1684 					   struct sk_buff *skb)
1685 {
1686 	struct ieee80211_local *local = sdata->local;
1687 	struct ieee802_11_elems elems;
1688 	struct sta_info *sta;
1689 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1690 	bool local_initiator;
1691 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1692 	int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1693 	struct ieee80211_tdls_ch_sw_params params = {};
1694 	int ret;
1695 
1696 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1697 	params.timestamp = rx_status->device_timestamp;
1698 
1699 	if (skb->len < baselen) {
1700 		tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1701 			 skb->len);
1702 		return -EINVAL;
1703 	}
1704 
1705 	mutex_lock(&local->sta_mtx);
1706 	sta = sta_info_get(sdata, tf->sa);
1707 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1708 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1709 			 tf->sa);
1710 		ret = -EINVAL;
1711 		goto out;
1712 	}
1713 
1714 	params.sta = &sta->sta;
1715 	params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1716 	if (params.status != 0) {
1717 		ret = 0;
1718 		goto call_drv;
1719 	}
1720 
1721 	ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1722 			       skb->len - baselen, false, &elems,
1723 			       NULL, NULL);
1724 	if (elems.parse_error) {
1725 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1726 		ret = -EINVAL;
1727 		goto out;
1728 	}
1729 
1730 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1731 		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1732 		ret = -EINVAL;
1733 		goto out;
1734 	}
1735 
1736 	/* validate the initiator is set correctly */
1737 	local_initiator =
1738 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1739 	if (local_initiator == sta->sta.tdls_initiator) {
1740 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1741 		ret = -EINVAL;
1742 		goto out;
1743 	}
1744 
1745 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1746 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1747 
1748 	params.tmpl_skb =
1749 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1750 	if (!params.tmpl_skb) {
1751 		ret = -ENOENT;
1752 		goto out;
1753 	}
1754 
1755 	ret = 0;
1756 call_drv:
1757 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1758 
1759 	tdls_dbg(sdata,
1760 		 "TDLS channel switch response received from %pM status %d\n",
1761 		 tf->sa, params.status);
1762 
1763 out:
1764 	mutex_unlock(&local->sta_mtx);
1765 	dev_kfree_skb_any(params.tmpl_skb);
1766 	return ret;
1767 }
1768 
1769 static int
1770 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1771 					  struct sk_buff *skb)
1772 {
1773 	struct ieee80211_local *local = sdata->local;
1774 	struct ieee802_11_elems elems;
1775 	struct cfg80211_chan_def chandef;
1776 	struct ieee80211_channel *chan;
1777 	enum nl80211_channel_type chan_type;
1778 	int freq;
1779 	u8 target_channel, oper_class;
1780 	bool local_initiator;
1781 	struct sta_info *sta;
1782 	enum nl80211_band band;
1783 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1784 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1785 	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1786 	struct ieee80211_tdls_ch_sw_params params = {};
1787 	int ret = 0;
1788 
1789 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1790 	params.timestamp = rx_status->device_timestamp;
1791 
1792 	if (skb->len < baselen) {
1793 		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1794 			 skb->len);
1795 		return -EINVAL;
1796 	}
1797 
1798 	target_channel = tf->u.chan_switch_req.target_channel;
1799 	oper_class = tf->u.chan_switch_req.oper_class;
1800 
1801 	/*
1802 	 * We can't easily infer the channel band. The operating class is
1803 	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1804 	 * solution here is to treat channels with number >14 as 5GHz ones,
1805 	 * and specifically check for the (oper_class, channel) combinations
1806 	 * where this doesn't hold. These are thankfully unique according to
1807 	 * IEEE802.11-2012.
1808 	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1809 	 * valid here.
1810 	 */
1811 	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1812 	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1813 	     target_channel < 14)
1814 		band = NL80211_BAND_5GHZ;
1815 	else
1816 		band = target_channel < 14 ? NL80211_BAND_2GHZ :
1817 					     NL80211_BAND_5GHZ;
1818 
1819 	freq = ieee80211_channel_to_frequency(target_channel, band);
1820 	if (freq == 0) {
1821 		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1822 			 target_channel);
1823 		return -EINVAL;
1824 	}
1825 
1826 	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1827 	if (!chan) {
1828 		tdls_dbg(sdata,
1829 			 "Unsupported channel for TDLS chan switch: %d\n",
1830 			 target_channel);
1831 		return -EINVAL;
1832 	}
1833 
1834 	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1835 			       skb->len - baselen, false, &elems, NULL, NULL);
1836 	if (elems.parse_error) {
1837 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1838 		return -EINVAL;
1839 	}
1840 
1841 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1842 		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1843 		return -EINVAL;
1844 	}
1845 
1846 	if (!elems.sec_chan_offs) {
1847 		chan_type = NL80211_CHAN_HT20;
1848 	} else {
1849 		switch (elems.sec_chan_offs->sec_chan_offs) {
1850 		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1851 			chan_type = NL80211_CHAN_HT40PLUS;
1852 			break;
1853 		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1854 			chan_type = NL80211_CHAN_HT40MINUS;
1855 			break;
1856 		default:
1857 			chan_type = NL80211_CHAN_HT20;
1858 			break;
1859 		}
1860 	}
1861 
1862 	cfg80211_chandef_create(&chandef, chan, chan_type);
1863 
1864 	/* we will be active on the TDLS link */
1865 	if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1866 					   sdata->wdev.iftype)) {
1867 		tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1868 		return -EINVAL;
1869 	}
1870 
1871 	mutex_lock(&local->sta_mtx);
1872 	sta = sta_info_get(sdata, tf->sa);
1873 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1874 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1875 			 tf->sa);
1876 		ret = -EINVAL;
1877 		goto out;
1878 	}
1879 
1880 	params.sta = &sta->sta;
1881 
1882 	/* validate the initiator is set correctly */
1883 	local_initiator =
1884 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1885 	if (local_initiator == sta->sta.tdls_initiator) {
1886 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1887 		ret = -EINVAL;
1888 		goto out;
1889 	}
1890 
1891 	/* peer should have known better */
1892 	if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1893 	    elems.sec_chan_offs->sec_chan_offs) {
1894 		tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1895 		ret = -ENOTSUPP;
1896 		goto out;
1897 	}
1898 
1899 	params.chandef = &chandef;
1900 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1901 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1902 
1903 	params.tmpl_skb =
1904 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1905 						   &params.ch_sw_tm_ie);
1906 	if (!params.tmpl_skb) {
1907 		ret = -ENOENT;
1908 		goto out;
1909 	}
1910 
1911 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1912 
1913 	tdls_dbg(sdata,
1914 		 "TDLS ch switch request received from %pM ch %d width %d\n",
1915 		 tf->sa, params.chandef->chan->center_freq,
1916 		 params.chandef->width);
1917 out:
1918 	mutex_unlock(&local->sta_mtx);
1919 	dev_kfree_skb_any(params.tmpl_skb);
1920 	return ret;
1921 }
1922 
1923 static void
1924 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1925 				      struct sk_buff *skb)
1926 {
1927 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1928 	struct wiphy *wiphy = sdata->local->hw.wiphy;
1929 
1930 	ASSERT_RTNL();
1931 
1932 	/* make sure the driver supports it */
1933 	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1934 		return;
1935 
1936 	/* we want to access the entire packet */
1937 	if (skb_linearize(skb))
1938 		return;
1939 	/*
1940 	 * The packet/size was already validated by mac80211 Rx path, only look
1941 	 * at the action type.
1942 	 */
1943 	switch (tf->action_code) {
1944 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1945 		ieee80211_process_tdls_channel_switch_req(sdata, skb);
1946 		break;
1947 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1948 		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1949 		break;
1950 	default:
1951 		WARN_ON_ONCE(1);
1952 		return;
1953 	}
1954 }
1955 
1956 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1957 {
1958 	struct sta_info *sta;
1959 	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1960 
1961 	rcu_read_lock();
1962 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1963 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1964 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1965 			continue;
1966 
1967 		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1968 					    NL80211_TDLS_TEARDOWN, reason,
1969 					    GFP_ATOMIC);
1970 	}
1971 	rcu_read_unlock();
1972 }
1973 
1974 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1975 {
1976 	struct ieee80211_local *local =
1977 		container_of(wk, struct ieee80211_local, tdls_chsw_work);
1978 	struct ieee80211_sub_if_data *sdata;
1979 	struct sk_buff *skb;
1980 	struct ieee80211_tdls_data *tf;
1981 
1982 	rtnl_lock();
1983 	while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1984 		tf = (struct ieee80211_tdls_data *)skb->data;
1985 		list_for_each_entry(sdata, &local->interfaces, list) {
1986 			if (!ieee80211_sdata_running(sdata) ||
1987 			    sdata->vif.type != NL80211_IFTYPE_STATION ||
1988 			    !ether_addr_equal(tf->da, sdata->vif.addr))
1989 				continue;
1990 
1991 			ieee80211_process_tdls_channel_switch(sdata, skb);
1992 			break;
1993 		}
1994 
1995 		kfree_skb(skb);
1996 	}
1997 	rtnl_unlock();
1998 }
1999 
2000 void ieee80211_tdls_handle_disconnect(struct ieee80211_sub_if_data *sdata,
2001 				      const u8 *peer, u16 reason)
2002 {
2003 	struct ieee80211_sta *sta;
2004 
2005 	rcu_read_lock();
2006 	sta = ieee80211_find_sta(&sdata->vif, peer);
2007 	if (!sta || !sta->tdls) {
2008 		rcu_read_unlock();
2009 		return;
2010 	}
2011 	rcu_read_unlock();
2012 
2013 	tdls_dbg(sdata, "disconnected from TDLS peer %pM (Reason: %u=%s)\n",
2014 		 peer, reason,
2015 		 ieee80211_get_reason_code_string(reason));
2016 
2017 	ieee80211_tdls_oper_request(&sdata->vif, peer,
2018 				    NL80211_TDLS_TEARDOWN,
2019 				    WLAN_REASON_TDLS_TEARDOWN_UNREACHABLE,
2020 				    GFP_ATOMIC);
2021 }
2022