xref: /linux/net/mac80211/tdls.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
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  *
8  * This file is GPLv2 as found in COPYING.
9  */
10 
11 #include <linux/ieee80211.h>
12 #include <linux/log2.h>
13 #include <net/cfg80211.h>
14 #include "ieee80211_i.h"
15 #include "driver-ops.h"
16 
17 /* give usermode some time for retries in setting up the TDLS session */
18 #define TDLS_PEER_SETUP_TIMEOUT	(15 * HZ)
19 
20 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
21 {
22 	struct ieee80211_sub_if_data *sdata;
23 	struct ieee80211_local *local;
24 
25 	sdata = container_of(wk, struct ieee80211_sub_if_data,
26 			     u.mgd.tdls_peer_del_work.work);
27 	local = sdata->local;
28 
29 	mutex_lock(&local->mtx);
30 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
31 		tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
32 		sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
33 		eth_zero_addr(sdata->u.mgd.tdls_peer);
34 	}
35 	mutex_unlock(&local->mtx);
36 }
37 
38 static void ieee80211_tdls_add_ext_capab(struct ieee80211_local *local,
39 					 struct sk_buff *skb)
40 {
41 	u8 *pos = (void *)skb_put(skb, 7);
42 	bool chan_switch = local->hw.wiphy->features &
43 			   NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
44 
45 	*pos++ = WLAN_EID_EXT_CAPABILITY;
46 	*pos++ = 5; /* len */
47 	*pos++ = 0x0;
48 	*pos++ = 0x0;
49 	*pos++ = 0x0;
50 	*pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
51 	*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
52 }
53 
54 static u8
55 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
56 			   struct sk_buff *skb, u16 start, u16 end,
57 			   u16 spacing)
58 {
59 	u8 subband_cnt = 0, ch_cnt = 0;
60 	struct ieee80211_channel *ch;
61 	struct cfg80211_chan_def chandef;
62 	int i, subband_start;
63 
64 	for (i = start; i <= end; i += spacing) {
65 		if (!ch_cnt)
66 			subband_start = i;
67 
68 		ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
69 		if (ch) {
70 			/* we will be active on the channel */
71 			u32 flags = IEEE80211_CHAN_DISABLED |
72 				    IEEE80211_CHAN_NO_IR;
73 			cfg80211_chandef_create(&chandef, ch,
74 						NL80211_CHAN_HT20);
75 			if (cfg80211_chandef_usable(sdata->local->hw.wiphy,
76 						    &chandef, flags)) {
77 				ch_cnt++;
78 				continue;
79 			}
80 		}
81 
82 		if (ch_cnt) {
83 			u8 *pos = skb_put(skb, 2);
84 			*pos++ = ieee80211_frequency_to_channel(subband_start);
85 			*pos++ = ch_cnt;
86 
87 			subband_cnt++;
88 			ch_cnt = 0;
89 		}
90 	}
91 
92 	return subband_cnt;
93 }
94 
95 static void
96 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
97 				 struct sk_buff *skb)
98 {
99 	/*
100 	 * Add possible channels for TDLS. These are channels that are allowed
101 	 * to be active.
102 	 */
103 	u8 subband_cnt;
104 	u8 *pos = skb_put(skb, 2);
105 
106 	*pos++ = WLAN_EID_SUPPORTED_CHANNELS;
107 
108 	/*
109 	 * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
110 	 * this doesn't happen in real world scenarios.
111 	 */
112 
113 	/* 2GHz, with 5MHz spacing */
114 	subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
115 
116 	/* 5GHz, with 20MHz spacing */
117 	subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
118 
119 	/* length */
120 	*pos = 2 * subband_cnt;
121 }
122 
123 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
124 {
125 	u8 *pos = (void *)skb_put(skb, 3);
126 
127 	*pos++ = WLAN_EID_BSS_COEX_2040;
128 	*pos++ = 1; /* len */
129 
130 	*pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
131 }
132 
133 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
134 					u16 status_code)
135 {
136 	struct ieee80211_local *local = sdata->local;
137 	u16 capab;
138 
139 	/* The capability will be 0 when sending a failure code */
140 	if (status_code != 0)
141 		return 0;
142 
143 	capab = 0;
144 	if (ieee80211_get_sdata_band(sdata) != IEEE80211_BAND_2GHZ)
145 		return capab;
146 
147 	if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
148 		capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
149 	if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE))
150 		capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
151 
152 	return capab;
153 }
154 
155 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
156 				       struct sk_buff *skb, const u8 *peer,
157 				       bool initiator)
158 {
159 	struct ieee80211_tdls_lnkie *lnkid;
160 	const u8 *init_addr, *rsp_addr;
161 
162 	if (initiator) {
163 		init_addr = sdata->vif.addr;
164 		rsp_addr = peer;
165 	} else {
166 		init_addr = peer;
167 		rsp_addr = sdata->vif.addr;
168 	}
169 
170 	lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
171 
172 	lnkid->ie_type = WLAN_EID_LINK_ID;
173 	lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
174 
175 	memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
176 	memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
177 	memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
178 }
179 
180 /* translate numbering in the WMM parameter IE to the mac80211 notation */
181 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
182 {
183 	switch (ac) {
184 	default:
185 		WARN_ON_ONCE(1);
186 	case 0:
187 		return IEEE80211_AC_BE;
188 	case 1:
189 		return IEEE80211_AC_BK;
190 	case 2:
191 		return IEEE80211_AC_VI;
192 	case 3:
193 		return IEEE80211_AC_VO;
194 	}
195 }
196 
197 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
198 {
199 	u8 ret;
200 
201 	ret = aifsn & 0x0f;
202 	if (acm)
203 		ret |= 0x10;
204 	ret |= (aci << 5) & 0x60;
205 	return ret;
206 }
207 
208 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
209 {
210 	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
211 	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
212 }
213 
214 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
215 					    struct sk_buff *skb)
216 {
217 	struct ieee80211_wmm_param_ie *wmm;
218 	struct ieee80211_tx_queue_params *txq;
219 	int i;
220 
221 	wmm = (void *)skb_put(skb, sizeof(*wmm));
222 	memset(wmm, 0, sizeof(*wmm));
223 
224 	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
225 	wmm->len = sizeof(*wmm) - 2;
226 
227 	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
228 	wmm->oui[1] = 0x50;
229 	wmm->oui[2] = 0xf2;
230 	wmm->oui_type = 2; /* WME */
231 	wmm->oui_subtype = 1; /* WME param */
232 	wmm->version = 1; /* WME ver */
233 	wmm->qos_info = 0; /* U-APSD not in use */
234 
235 	/*
236 	 * Use the EDCA parameters defined for the BSS, or default if the AP
237 	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
238 	 */
239 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
240 		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
241 		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
242 							       txq->acm, i);
243 		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
244 		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
245 	}
246 }
247 
248 static void
249 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
250 				   struct sk_buff *skb, const u8 *peer,
251 				   u8 action_code, bool initiator,
252 				   const u8 *extra_ies, size_t extra_ies_len)
253 {
254 	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
255 	struct ieee80211_local *local = sdata->local;
256 	struct ieee80211_supported_band *sband;
257 	struct ieee80211_sta_ht_cap ht_cap;
258 	struct sta_info *sta = NULL;
259 	size_t offset = 0, noffset;
260 	u8 *pos;
261 
262 	rcu_read_lock();
263 
264 	/* we should have the peer STA if we're already responding */
265 	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
266 		sta = sta_info_get(sdata, peer);
267 		if (WARN_ON_ONCE(!sta)) {
268 			rcu_read_unlock();
269 			return;
270 		}
271 	}
272 
273 	ieee80211_add_srates_ie(sdata, skb, false, band);
274 	ieee80211_add_ext_srates_ie(sdata, skb, false, band);
275 	ieee80211_tdls_add_supp_channels(sdata, skb);
276 
277 	/* add any custom IEs that go before Extended Capabilities */
278 	if (extra_ies_len) {
279 		static const u8 before_ext_cap[] = {
280 			WLAN_EID_SUPP_RATES,
281 			WLAN_EID_COUNTRY,
282 			WLAN_EID_EXT_SUPP_RATES,
283 			WLAN_EID_SUPPORTED_CHANNELS,
284 			WLAN_EID_RSN,
285 		};
286 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
287 					     before_ext_cap,
288 					     ARRAY_SIZE(before_ext_cap),
289 					     offset);
290 		pos = skb_put(skb, noffset - offset);
291 		memcpy(pos, extra_ies + offset, noffset - offset);
292 		offset = noffset;
293 	}
294 
295 	ieee80211_tdls_add_ext_capab(local, skb);
296 
297 	/* add the QoS element if we support it */
298 	if (local->hw.queues >= IEEE80211_NUM_ACS &&
299 	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
300 		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
301 
302 	/* add any custom IEs that go before HT capabilities */
303 	if (extra_ies_len) {
304 		static const u8 before_ht_cap[] = {
305 			WLAN_EID_SUPP_RATES,
306 			WLAN_EID_COUNTRY,
307 			WLAN_EID_EXT_SUPP_RATES,
308 			WLAN_EID_SUPPORTED_CHANNELS,
309 			WLAN_EID_RSN,
310 			WLAN_EID_EXT_CAPABILITY,
311 			WLAN_EID_QOS_CAPA,
312 			WLAN_EID_FAST_BSS_TRANSITION,
313 			WLAN_EID_TIMEOUT_INTERVAL,
314 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
315 		};
316 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
317 					     before_ht_cap,
318 					     ARRAY_SIZE(before_ht_cap),
319 					     offset);
320 		pos = skb_put(skb, noffset - offset);
321 		memcpy(pos, extra_ies + offset, noffset - offset);
322 		offset = noffset;
323 	}
324 
325 	/*
326 	 * with TDLS we can switch channels, and HT-caps are not necessarily
327 	 * the same on all bands. The specification limits the setup to a
328 	 * single HT-cap, so use the current band for now.
329 	 */
330 	sband = local->hw.wiphy->bands[band];
331 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
332 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
333 	     action_code == WLAN_TDLS_SETUP_RESPONSE) &&
334 	    ht_cap.ht_supported && (!sta || sta->sta.ht_cap.ht_supported)) {
335 		if (action_code == WLAN_TDLS_SETUP_REQUEST) {
336 			ieee80211_apply_htcap_overrides(sdata, &ht_cap);
337 
338 			/* disable SMPS in TDLS initiator */
339 			ht_cap.cap |= (WLAN_HT_CAP_SM_PS_DISABLED
340 				       << IEEE80211_HT_CAP_SM_PS_SHIFT);
341 		} else {
342 			/* disable SMPS in TDLS responder */
343 			sta->sta.ht_cap.cap |=
344 				(WLAN_HT_CAP_SM_PS_DISABLED
345 				 << IEEE80211_HT_CAP_SM_PS_SHIFT);
346 
347 			/* the peer caps are already intersected with our own */
348 			memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
349 		}
350 
351 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
352 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
353 	}
354 
355 	rcu_read_unlock();
356 
357 	if (ht_cap.ht_supported &&
358 	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
359 		ieee80211_tdls_add_bss_coex_ie(skb);
360 
361 	/* add any remaining IEs */
362 	if (extra_ies_len) {
363 		noffset = extra_ies_len;
364 		pos = skb_put(skb, noffset - offset);
365 		memcpy(pos, extra_ies + offset, noffset - offset);
366 	}
367 
368 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
369 }
370 
371 static void
372 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
373 				 struct sk_buff *skb, const u8 *peer,
374 				 bool initiator, const u8 *extra_ies,
375 				 size_t extra_ies_len)
376 {
377 	struct ieee80211_local *local = sdata->local;
378 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
379 	size_t offset = 0, noffset;
380 	struct sta_info *sta, *ap_sta;
381 	u8 *pos;
382 
383 	rcu_read_lock();
384 
385 	sta = sta_info_get(sdata, peer);
386 	ap_sta = sta_info_get(sdata, ifmgd->bssid);
387 	if (WARN_ON_ONCE(!sta || !ap_sta)) {
388 		rcu_read_unlock();
389 		return;
390 	}
391 
392 	/* add any custom IEs that go before the QoS IE */
393 	if (extra_ies_len) {
394 		static const u8 before_qos[] = {
395 			WLAN_EID_RSN,
396 		};
397 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
398 					     before_qos,
399 					     ARRAY_SIZE(before_qos),
400 					     offset);
401 		pos = skb_put(skb, noffset - offset);
402 		memcpy(pos, extra_ies + offset, noffset - offset);
403 		offset = noffset;
404 	}
405 
406 	/* add the QoS param IE if both the peer and we support it */
407 	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
408 		ieee80211_tdls_add_wmm_param_ie(sdata, skb);
409 
410 	/* add any custom IEs that go before HT operation */
411 	if (extra_ies_len) {
412 		static const u8 before_ht_op[] = {
413 			WLAN_EID_RSN,
414 			WLAN_EID_QOS_CAPA,
415 			WLAN_EID_FAST_BSS_TRANSITION,
416 			WLAN_EID_TIMEOUT_INTERVAL,
417 		};
418 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
419 					     before_ht_op,
420 					     ARRAY_SIZE(before_ht_op),
421 					     offset);
422 		pos = skb_put(skb, noffset - offset);
423 		memcpy(pos, extra_ies + offset, noffset - offset);
424 		offset = noffset;
425 	}
426 
427 	/* if HT support is only added in TDLS, we need an HT-operation IE */
428 	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
429 		struct ieee80211_chanctx_conf *chanctx_conf =
430 				rcu_dereference(sdata->vif.chanctx_conf);
431 		if (!WARN_ON(!chanctx_conf)) {
432 			pos = skb_put(skb, 2 +
433 				      sizeof(struct ieee80211_ht_operation));
434 			/* send an empty HT operation IE */
435 			ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
436 						   &chanctx_conf->def, 0);
437 		}
438 	}
439 
440 	rcu_read_unlock();
441 
442 	/* add any remaining IEs */
443 	if (extra_ies_len) {
444 		noffset = extra_ies_len;
445 		pos = skb_put(skb, noffset - offset);
446 		memcpy(pos, extra_ies + offset, noffset - offset);
447 	}
448 
449 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
450 }
451 
452 static void
453 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
454 				       struct sk_buff *skb, const u8 *peer,
455 				       bool initiator, const u8 *extra_ies,
456 				       size_t extra_ies_len, u8 oper_class,
457 				       struct cfg80211_chan_def *chandef)
458 {
459 	struct ieee80211_tdls_data *tf;
460 	size_t offset = 0, noffset;
461 	u8 *pos;
462 
463 	if (WARN_ON_ONCE(!chandef))
464 		return;
465 
466 	tf = (void *)skb->data;
467 	tf->u.chan_switch_req.target_channel =
468 		ieee80211_frequency_to_channel(chandef->chan->center_freq);
469 	tf->u.chan_switch_req.oper_class = oper_class;
470 
471 	if (extra_ies_len) {
472 		static const u8 before_lnkie[] = {
473 			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
474 		};
475 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
476 					     before_lnkie,
477 					     ARRAY_SIZE(before_lnkie),
478 					     offset);
479 		pos = skb_put(skb, noffset - offset);
480 		memcpy(pos, extra_ies + offset, noffset - offset);
481 		offset = noffset;
482 	}
483 
484 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
485 
486 	/* add any remaining IEs */
487 	if (extra_ies_len) {
488 		noffset = extra_ies_len;
489 		pos = skb_put(skb, noffset - offset);
490 		memcpy(pos, extra_ies + offset, noffset - offset);
491 	}
492 }
493 
494 static void
495 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
496 					struct sk_buff *skb, const u8 *peer,
497 					u16 status_code, bool initiator,
498 					const u8 *extra_ies,
499 					size_t extra_ies_len)
500 {
501 	if (status_code == 0)
502 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
503 
504 	if (extra_ies_len)
505 		memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
506 }
507 
508 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
509 				   struct sk_buff *skb, const u8 *peer,
510 				   u8 action_code, u16 status_code,
511 				   bool initiator, const u8 *extra_ies,
512 				   size_t extra_ies_len, u8 oper_class,
513 				   struct cfg80211_chan_def *chandef)
514 {
515 	switch (action_code) {
516 	case WLAN_TDLS_SETUP_REQUEST:
517 	case WLAN_TDLS_SETUP_RESPONSE:
518 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
519 		if (status_code == 0)
520 			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
521 							   action_code,
522 							   initiator,
523 							   extra_ies,
524 							   extra_ies_len);
525 		break;
526 	case WLAN_TDLS_SETUP_CONFIRM:
527 		if (status_code == 0)
528 			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
529 							 initiator, extra_ies,
530 							 extra_ies_len);
531 		break;
532 	case WLAN_TDLS_TEARDOWN:
533 	case WLAN_TDLS_DISCOVERY_REQUEST:
534 		if (extra_ies_len)
535 			memcpy(skb_put(skb, extra_ies_len), extra_ies,
536 			       extra_ies_len);
537 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
538 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
539 		break;
540 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
541 		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
542 						       initiator, extra_ies,
543 						       extra_ies_len,
544 						       oper_class, chandef);
545 		break;
546 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
547 		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
548 							status_code,
549 							initiator, extra_ies,
550 							extra_ies_len);
551 		break;
552 	}
553 
554 }
555 
556 static int
557 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
558 			       const u8 *peer, u8 action_code, u8 dialog_token,
559 			       u16 status_code, struct sk_buff *skb)
560 {
561 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
562 	struct ieee80211_tdls_data *tf;
563 
564 	tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
565 
566 	memcpy(tf->da, peer, ETH_ALEN);
567 	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
568 	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
569 	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
570 
571 	/* network header is after the ethernet header */
572 	skb_set_network_header(skb, ETH_HLEN);
573 
574 	switch (action_code) {
575 	case WLAN_TDLS_SETUP_REQUEST:
576 		tf->category = WLAN_CATEGORY_TDLS;
577 		tf->action_code = WLAN_TDLS_SETUP_REQUEST;
578 
579 		skb_put(skb, sizeof(tf->u.setup_req));
580 		tf->u.setup_req.dialog_token = dialog_token;
581 		tf->u.setup_req.capability =
582 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
583 								 status_code));
584 		break;
585 	case WLAN_TDLS_SETUP_RESPONSE:
586 		tf->category = WLAN_CATEGORY_TDLS;
587 		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
588 
589 		skb_put(skb, sizeof(tf->u.setup_resp));
590 		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
591 		tf->u.setup_resp.dialog_token = dialog_token;
592 		tf->u.setup_resp.capability =
593 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
594 								 status_code));
595 		break;
596 	case WLAN_TDLS_SETUP_CONFIRM:
597 		tf->category = WLAN_CATEGORY_TDLS;
598 		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
599 
600 		skb_put(skb, sizeof(tf->u.setup_cfm));
601 		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
602 		tf->u.setup_cfm.dialog_token = dialog_token;
603 		break;
604 	case WLAN_TDLS_TEARDOWN:
605 		tf->category = WLAN_CATEGORY_TDLS;
606 		tf->action_code = WLAN_TDLS_TEARDOWN;
607 
608 		skb_put(skb, sizeof(tf->u.teardown));
609 		tf->u.teardown.reason_code = cpu_to_le16(status_code);
610 		break;
611 	case WLAN_TDLS_DISCOVERY_REQUEST:
612 		tf->category = WLAN_CATEGORY_TDLS;
613 		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
614 
615 		skb_put(skb, sizeof(tf->u.discover_req));
616 		tf->u.discover_req.dialog_token = dialog_token;
617 		break;
618 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
619 		tf->category = WLAN_CATEGORY_TDLS;
620 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
621 
622 		skb_put(skb, sizeof(tf->u.chan_switch_req));
623 		break;
624 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
625 		tf->category = WLAN_CATEGORY_TDLS;
626 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
627 
628 		skb_put(skb, sizeof(tf->u.chan_switch_resp));
629 		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
630 		break;
631 	default:
632 		return -EINVAL;
633 	}
634 
635 	return 0;
636 }
637 
638 static int
639 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
640 			   const u8 *peer, u8 action_code, u8 dialog_token,
641 			   u16 status_code, struct sk_buff *skb)
642 {
643 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
644 	struct ieee80211_mgmt *mgmt;
645 
646 	mgmt = (void *)skb_put(skb, 24);
647 	memset(mgmt, 0, 24);
648 	memcpy(mgmt->da, peer, ETH_ALEN);
649 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
650 	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
651 
652 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
653 					  IEEE80211_STYPE_ACTION);
654 
655 	switch (action_code) {
656 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
657 		skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
658 		mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
659 		mgmt->u.action.u.tdls_discover_resp.action_code =
660 			WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
661 		mgmt->u.action.u.tdls_discover_resp.dialog_token =
662 			dialog_token;
663 		mgmt->u.action.u.tdls_discover_resp.capability =
664 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
665 								 status_code));
666 		break;
667 	default:
668 		return -EINVAL;
669 	}
670 
671 	return 0;
672 }
673 
674 static struct sk_buff *
675 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
676 				      const u8 *peer, u8 action_code,
677 				      u8 dialog_token, u16 status_code,
678 				      bool initiator, const u8 *extra_ies,
679 				      size_t extra_ies_len, u8 oper_class,
680 				      struct cfg80211_chan_def *chandef)
681 {
682 	struct ieee80211_local *local = sdata->local;
683 	struct sk_buff *skb;
684 	int ret;
685 
686 	skb = netdev_alloc_skb(sdata->dev,
687 			       local->hw.extra_tx_headroom +
688 			       max(sizeof(struct ieee80211_mgmt),
689 				   sizeof(struct ieee80211_tdls_data)) +
690 			       50 + /* supported rates */
691 			       7 + /* ext capab */
692 			       26 + /* max(WMM-info, WMM-param) */
693 			       2 + max(sizeof(struct ieee80211_ht_cap),
694 				       sizeof(struct ieee80211_ht_operation)) +
695 			       50 + /* supported channels */
696 			       3 + /* 40/20 BSS coex */
697 			       extra_ies_len +
698 			       sizeof(struct ieee80211_tdls_lnkie));
699 	if (!skb)
700 		return NULL;
701 
702 	skb_reserve(skb, local->hw.extra_tx_headroom);
703 
704 	switch (action_code) {
705 	case WLAN_TDLS_SETUP_REQUEST:
706 	case WLAN_TDLS_SETUP_RESPONSE:
707 	case WLAN_TDLS_SETUP_CONFIRM:
708 	case WLAN_TDLS_TEARDOWN:
709 	case WLAN_TDLS_DISCOVERY_REQUEST:
710 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
711 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
712 		ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
713 						     sdata->dev, peer,
714 						     action_code, dialog_token,
715 						     status_code, skb);
716 		break;
717 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
718 		ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
719 						 peer, action_code,
720 						 dialog_token, status_code,
721 						 skb);
722 		break;
723 	default:
724 		ret = -ENOTSUPP;
725 		break;
726 	}
727 
728 	if (ret < 0)
729 		goto fail;
730 
731 	ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
732 			       initiator, extra_ies, extra_ies_len, oper_class,
733 			       chandef);
734 	return skb;
735 
736 fail:
737 	dev_kfree_skb(skb);
738 	return NULL;
739 }
740 
741 static int
742 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
743 				const u8 *peer, u8 action_code, u8 dialog_token,
744 				u16 status_code, u32 peer_capability,
745 				bool initiator, const u8 *extra_ies,
746 				size_t extra_ies_len, u8 oper_class,
747 				struct cfg80211_chan_def *chandef)
748 {
749 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
750 	struct sk_buff *skb = NULL;
751 	struct sta_info *sta;
752 	u32 flags = 0;
753 	int ret = 0;
754 
755 	rcu_read_lock();
756 	sta = sta_info_get(sdata, peer);
757 
758 	/* infer the initiator if we can, to support old userspace */
759 	switch (action_code) {
760 	case WLAN_TDLS_SETUP_REQUEST:
761 		if (sta) {
762 			set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
763 			sta->sta.tdls_initiator = false;
764 		}
765 		/* fall-through */
766 	case WLAN_TDLS_SETUP_CONFIRM:
767 	case WLAN_TDLS_DISCOVERY_REQUEST:
768 		initiator = true;
769 		break;
770 	case WLAN_TDLS_SETUP_RESPONSE:
771 		/*
772 		 * In some testing scenarios, we send a request and response.
773 		 * Make the last packet sent take effect for the initiator
774 		 * value.
775 		 */
776 		if (sta) {
777 			clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
778 			sta->sta.tdls_initiator = true;
779 		}
780 		/* fall-through */
781 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
782 		initiator = false;
783 		break;
784 	case WLAN_TDLS_TEARDOWN:
785 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
786 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
787 		/* any value is ok */
788 		break;
789 	default:
790 		ret = -ENOTSUPP;
791 		break;
792 	}
793 
794 	if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
795 		initiator = true;
796 
797 	rcu_read_unlock();
798 	if (ret < 0)
799 		goto fail;
800 
801 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
802 						    dialog_token, status_code,
803 						    initiator, extra_ies,
804 						    extra_ies_len, oper_class,
805 						    chandef);
806 	if (!skb) {
807 		ret = -EINVAL;
808 		goto fail;
809 	}
810 
811 	if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
812 		ieee80211_tx_skb(sdata, skb);
813 		return 0;
814 	}
815 
816 	/*
817 	 * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
818 	 * we should default to AC_VI.
819 	 */
820 	switch (action_code) {
821 	case WLAN_TDLS_SETUP_REQUEST:
822 	case WLAN_TDLS_SETUP_RESPONSE:
823 		skb_set_queue_mapping(skb, IEEE80211_AC_BK);
824 		skb->priority = 2;
825 		break;
826 	default:
827 		skb_set_queue_mapping(skb, IEEE80211_AC_VI);
828 		skb->priority = 5;
829 		break;
830 	}
831 
832 	/*
833 	 * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
834 	 * Later, if no ACK is returned from peer, we will re-send the teardown
835 	 * packet through the AP.
836 	 */
837 	if ((action_code == WLAN_TDLS_TEARDOWN) &&
838 	    (sdata->local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)) {
839 		struct sta_info *sta = NULL;
840 		bool try_resend; /* Should we keep skb for possible resend */
841 
842 		/* If not sending directly to peer - no point in keeping skb */
843 		rcu_read_lock();
844 		sta = sta_info_get(sdata, peer);
845 		try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
846 		rcu_read_unlock();
847 
848 		spin_lock_bh(&sdata->u.mgd.teardown_lock);
849 		if (try_resend && !sdata->u.mgd.teardown_skb) {
850 			/* Mark it as requiring TX status callback  */
851 			flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
852 				 IEEE80211_TX_INTFL_MLME_CONN_TX;
853 
854 			/*
855 			 * skb is copied since mac80211 will later set
856 			 * properties that might not be the same as the AP,
857 			 * such as encryption, QoS, addresses, etc.
858 			 *
859 			 * No problem if skb_copy() fails, so no need to check.
860 			 */
861 			sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
862 			sdata->u.mgd.orig_teardown_skb = skb;
863 		}
864 		spin_unlock_bh(&sdata->u.mgd.teardown_lock);
865 	}
866 
867 	/* disable bottom halves when entering the Tx path */
868 	local_bh_disable();
869 	__ieee80211_subif_start_xmit(skb, dev, flags);
870 	local_bh_enable();
871 
872 	return ret;
873 
874 fail:
875 	dev_kfree_skb(skb);
876 	return ret;
877 }
878 
879 static int
880 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
881 			  const u8 *peer, u8 action_code, u8 dialog_token,
882 			  u16 status_code, u32 peer_capability, bool initiator,
883 			  const u8 *extra_ies, size_t extra_ies_len)
884 {
885 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
886 	struct ieee80211_local *local = sdata->local;
887 	int ret;
888 
889 	mutex_lock(&local->mtx);
890 
891 	/* we don't support concurrent TDLS peer setups */
892 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
893 	    !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
894 		ret = -EBUSY;
895 		goto exit;
896 	}
897 
898 	/*
899 	 * make sure we have a STA representing the peer so we drop or buffer
900 	 * non-TDLS-setup frames to the peer. We can't send other packets
901 	 * during setup through the AP path.
902 	 * Allow error packets to be sent - sometimes we don't even add a STA
903 	 * before failing the setup.
904 	 */
905 	if (status_code == 0) {
906 		rcu_read_lock();
907 		if (!sta_info_get(sdata, peer)) {
908 			rcu_read_unlock();
909 			ret = -ENOLINK;
910 			goto exit;
911 		}
912 		rcu_read_unlock();
913 	}
914 
915 	ieee80211_flush_queues(local, sdata);
916 
917 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
918 					      dialog_token, status_code,
919 					      peer_capability, initiator,
920 					      extra_ies, extra_ies_len, 0,
921 					      NULL);
922 	if (ret < 0)
923 		goto exit;
924 
925 	memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
926 	ieee80211_queue_delayed_work(&sdata->local->hw,
927 				     &sdata->u.mgd.tdls_peer_del_work,
928 				     TDLS_PEER_SETUP_TIMEOUT);
929 
930 exit:
931 	mutex_unlock(&local->mtx);
932 	return ret;
933 }
934 
935 static int
936 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
937 			     const u8 *peer, u8 action_code, u8 dialog_token,
938 			     u16 status_code, u32 peer_capability,
939 			     bool initiator, const u8 *extra_ies,
940 			     size_t extra_ies_len)
941 {
942 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
943 	struct ieee80211_local *local = sdata->local;
944 	struct sta_info *sta;
945 	int ret;
946 
947 	/*
948 	 * No packets can be transmitted to the peer via the AP during setup -
949 	 * the STA is set as a TDLS peer, but is not authorized.
950 	 * During teardown, we prevent direct transmissions by stopping the
951 	 * queues and flushing all direct packets.
952 	 */
953 	ieee80211_stop_vif_queues(local, sdata,
954 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
955 	ieee80211_flush_queues(local, sdata);
956 
957 	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
958 					      dialog_token, status_code,
959 					      peer_capability, initiator,
960 					      extra_ies, extra_ies_len, 0,
961 					      NULL);
962 	if (ret < 0)
963 		sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
964 			  ret);
965 
966 	/*
967 	 * Remove the STA AUTH flag to force further traffic through the AP. If
968 	 * the STA was unreachable, it was already removed.
969 	 */
970 	rcu_read_lock();
971 	sta = sta_info_get(sdata, peer);
972 	if (sta)
973 		clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
974 	rcu_read_unlock();
975 
976 	ieee80211_wake_vif_queues(local, sdata,
977 				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
978 
979 	return 0;
980 }
981 
982 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
983 			const u8 *peer, u8 action_code, u8 dialog_token,
984 			u16 status_code, u32 peer_capability,
985 			bool initiator, const u8 *extra_ies,
986 			size_t extra_ies_len)
987 {
988 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
989 	int ret;
990 
991 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
992 		return -ENOTSUPP;
993 
994 	/* make sure we are in managed mode, and associated */
995 	if (sdata->vif.type != NL80211_IFTYPE_STATION ||
996 	    !sdata->u.mgd.associated)
997 		return -EINVAL;
998 
999 	switch (action_code) {
1000 	case WLAN_TDLS_SETUP_REQUEST:
1001 	case WLAN_TDLS_SETUP_RESPONSE:
1002 		ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1003 						dialog_token, status_code,
1004 						peer_capability, initiator,
1005 						extra_ies, extra_ies_len);
1006 		break;
1007 	case WLAN_TDLS_TEARDOWN:
1008 		ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1009 						   action_code, dialog_token,
1010 						   status_code,
1011 						   peer_capability, initiator,
1012 						   extra_ies, extra_ies_len);
1013 		break;
1014 	case WLAN_TDLS_DISCOVERY_REQUEST:
1015 		/*
1016 		 * Protect the discovery so we can hear the TDLS discovery
1017 		 * response frame. It is transmitted directly and not buffered
1018 		 * by the AP.
1019 		 */
1020 		drv_mgd_protect_tdls_discover(sdata->local, sdata);
1021 		/* fall-through */
1022 	case WLAN_TDLS_SETUP_CONFIRM:
1023 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1024 		/* no special handling */
1025 		ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1026 						      action_code,
1027 						      dialog_token,
1028 						      status_code,
1029 						      peer_capability,
1030 						      initiator, extra_ies,
1031 						      extra_ies_len, 0, NULL);
1032 		break;
1033 	default:
1034 		ret = -EOPNOTSUPP;
1035 		break;
1036 	}
1037 
1038 	tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1039 		 action_code, peer, ret);
1040 	return ret;
1041 }
1042 
1043 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1044 			const u8 *peer, enum nl80211_tdls_operation oper)
1045 {
1046 	struct sta_info *sta;
1047 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1048 	struct ieee80211_local *local = sdata->local;
1049 	int ret;
1050 
1051 	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1052 		return -ENOTSUPP;
1053 
1054 	if (sdata->vif.type != NL80211_IFTYPE_STATION)
1055 		return -EINVAL;
1056 
1057 	switch (oper) {
1058 	case NL80211_TDLS_ENABLE_LINK:
1059 	case NL80211_TDLS_DISABLE_LINK:
1060 		break;
1061 	case NL80211_TDLS_TEARDOWN:
1062 	case NL80211_TDLS_SETUP:
1063 	case NL80211_TDLS_DISCOVERY_REQ:
1064 		/* We don't support in-driver setup/teardown/discovery */
1065 		return -ENOTSUPP;
1066 	}
1067 
1068 	mutex_lock(&local->mtx);
1069 	tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1070 
1071 	switch (oper) {
1072 	case NL80211_TDLS_ENABLE_LINK:
1073 		rcu_read_lock();
1074 		sta = sta_info_get(sdata, peer);
1075 		if (!sta) {
1076 			rcu_read_unlock();
1077 			ret = -ENOLINK;
1078 			break;
1079 		}
1080 
1081 		set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1082 		rcu_read_unlock();
1083 
1084 		WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1085 			     !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1086 		ret = 0;
1087 		break;
1088 	case NL80211_TDLS_DISABLE_LINK:
1089 		/*
1090 		 * The teardown message in ieee80211_tdls_mgmt_teardown() was
1091 		 * created while the queues were stopped, so it might still be
1092 		 * pending. Before flushing the queues we need to be sure the
1093 		 * message is handled by the tasklet handling pending messages,
1094 		 * otherwise we might start destroying the station before
1095 		 * sending the teardown packet.
1096 		 * Note that this only forces the tasklet to flush pendings -
1097 		 * not to stop the tasklet from rescheduling itself.
1098 		 */
1099 		tasklet_kill(&local->tx_pending_tasklet);
1100 		/* flush a potentially queued teardown packet */
1101 		ieee80211_flush_queues(local, sdata);
1102 
1103 		ret = sta_info_destroy_addr(sdata, peer);
1104 		break;
1105 	default:
1106 		ret = -ENOTSUPP;
1107 		break;
1108 	}
1109 
1110 	if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1111 		cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1112 		eth_zero_addr(sdata->u.mgd.tdls_peer);
1113 	}
1114 
1115 	mutex_unlock(&local->mtx);
1116 	return ret;
1117 }
1118 
1119 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1120 				 enum nl80211_tdls_operation oper,
1121 				 u16 reason_code, gfp_t gfp)
1122 {
1123 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1124 
1125 	if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1126 		sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1127 			  oper);
1128 		return;
1129 	}
1130 
1131 	cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1132 }
1133 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1134 
1135 static void
1136 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1137 {
1138 	struct ieee80211_ch_switch_timing *ch_sw;
1139 
1140 	*buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1141 	*buf++ = sizeof(struct ieee80211_ch_switch_timing);
1142 
1143 	ch_sw = (void *)buf;
1144 	ch_sw->switch_time = cpu_to_le16(switch_time);
1145 	ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1146 }
1147 
1148 /* find switch timing IE in SKB ready for Tx */
1149 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1150 {
1151 	struct ieee80211_tdls_data *tf;
1152 	const u8 *ie_start;
1153 
1154 	/*
1155 	 * Get the offset for the new location of the switch timing IE.
1156 	 * The SKB network header will now point to the "payload_type"
1157 	 * element of the TDLS data frame struct.
1158 	 */
1159 	tf = container_of(skb->data + skb_network_offset(skb),
1160 			  struct ieee80211_tdls_data, payload_type);
1161 	ie_start = tf->u.chan_switch_req.variable;
1162 	return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1163 				skb->len - (ie_start - skb->data));
1164 }
1165 
1166 static struct sk_buff *
1167 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1168 			      struct cfg80211_chan_def *chandef,
1169 			      u32 *ch_sw_tm_ie_offset)
1170 {
1171 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1172 	u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1173 		     2 + sizeof(struct ieee80211_ch_switch_timing)];
1174 	int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1175 	u8 *pos = extra_ies;
1176 	struct sk_buff *skb;
1177 
1178 	/*
1179 	 * if chandef points to a wide channel add a Secondary-Channel
1180 	 * Offset information element
1181 	 */
1182 	if (chandef->width == NL80211_CHAN_WIDTH_40) {
1183 		struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1184 		bool ht40plus;
1185 
1186 		*pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1187 		*pos++ = sizeof(*sec_chan_ie);
1188 		sec_chan_ie = (void *)pos;
1189 
1190 		ht40plus = cfg80211_get_chandef_type(chandef) ==
1191 							NL80211_CHAN_HT40PLUS;
1192 		sec_chan_ie->sec_chan_offs = ht40plus ?
1193 					     IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1194 					     IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1195 		pos += sizeof(*sec_chan_ie);
1196 
1197 		extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1198 	}
1199 
1200 	/* just set the values to 0, this is a template */
1201 	iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1202 
1203 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1204 					      WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1205 					      0, 0, !sta->sta.tdls_initiator,
1206 					      extra_ies, extra_ies_len,
1207 					      oper_class, chandef);
1208 	if (!skb)
1209 		return NULL;
1210 
1211 	skb = ieee80211_build_data_template(sdata, skb, 0);
1212 	if (IS_ERR(skb)) {
1213 		tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1214 		return NULL;
1215 	}
1216 
1217 	if (ch_sw_tm_ie_offset) {
1218 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1219 
1220 		if (!tm_ie) {
1221 			tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1222 			dev_kfree_skb_any(skb);
1223 			return NULL;
1224 		}
1225 
1226 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1227 	}
1228 
1229 	tdls_dbg(sdata,
1230 		 "TDLS channel switch request template for %pM ch %d width %d\n",
1231 		 sta->sta.addr, chandef->chan->center_freq, chandef->width);
1232 	return skb;
1233 }
1234 
1235 int
1236 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1237 			      const u8 *addr, u8 oper_class,
1238 			      struct cfg80211_chan_def *chandef)
1239 {
1240 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1241 	struct ieee80211_local *local = sdata->local;
1242 	struct sta_info *sta;
1243 	struct sk_buff *skb = NULL;
1244 	u32 ch_sw_tm_ie;
1245 	int ret;
1246 
1247 	mutex_lock(&local->sta_mtx);
1248 	sta = sta_info_get(sdata, addr);
1249 	if (!sta) {
1250 		tdls_dbg(sdata,
1251 			 "Invalid TDLS peer %pM for channel switch request\n",
1252 			 addr);
1253 		ret = -ENOENT;
1254 		goto out;
1255 	}
1256 
1257 	if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1258 		tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1259 			 addr);
1260 		ret = -ENOTSUPP;
1261 		goto out;
1262 	}
1263 
1264 	skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1265 					    &ch_sw_tm_ie);
1266 	if (!skb) {
1267 		ret = -ENOENT;
1268 		goto out;
1269 	}
1270 
1271 	ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1272 				      chandef, skb, ch_sw_tm_ie);
1273 	if (!ret)
1274 		set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1275 
1276 out:
1277 	mutex_unlock(&local->sta_mtx);
1278 	dev_kfree_skb_any(skb);
1279 	return ret;
1280 }
1281 
1282 void
1283 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1284 				     struct net_device *dev,
1285 				     const u8 *addr)
1286 {
1287 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1288 	struct ieee80211_local *local = sdata->local;
1289 	struct sta_info *sta;
1290 
1291 	mutex_lock(&local->sta_mtx);
1292 	sta = sta_info_get(sdata, addr);
1293 	if (!sta) {
1294 		tdls_dbg(sdata,
1295 			 "Invalid TDLS peer %pM for channel switch cancel\n",
1296 			 addr);
1297 		goto out;
1298 	}
1299 
1300 	if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1301 		tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1302 			 addr);
1303 		goto out;
1304 	}
1305 
1306 	drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1307 	clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1308 
1309 out:
1310 	mutex_unlock(&local->sta_mtx);
1311 }
1312 
1313 static struct sk_buff *
1314 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1315 				   u32 *ch_sw_tm_ie_offset)
1316 {
1317 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1318 	struct sk_buff *skb;
1319 	u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1320 
1321 	/* initial timing are always zero in the template */
1322 	iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1323 
1324 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1325 					WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1326 					0, 0, !sta->sta.tdls_initiator,
1327 					extra_ies, sizeof(extra_ies), 0, NULL);
1328 	if (!skb)
1329 		return NULL;
1330 
1331 	skb = ieee80211_build_data_template(sdata, skb, 0);
1332 	if (IS_ERR(skb)) {
1333 		tdls_dbg(sdata,
1334 			 "Failed building TDLS channel switch resp frame\n");
1335 		return NULL;
1336 	}
1337 
1338 	if (ch_sw_tm_ie_offset) {
1339 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1340 
1341 		if (!tm_ie) {
1342 			tdls_dbg(sdata,
1343 				 "No switch timing IE in TDLS switch resp\n");
1344 			dev_kfree_skb_any(skb);
1345 			return NULL;
1346 		}
1347 
1348 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1349 	}
1350 
1351 	tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1352 		 sta->sta.addr);
1353 	return skb;
1354 }
1355 
1356 static int
1357 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1358 					   struct sk_buff *skb)
1359 {
1360 	struct ieee80211_local *local = sdata->local;
1361 	struct ieee802_11_elems elems;
1362 	struct sta_info *sta;
1363 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1364 	bool local_initiator;
1365 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1366 	int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1367 	struct ieee80211_tdls_ch_sw_params params = {};
1368 	int ret;
1369 
1370 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1371 	params.timestamp = rx_status->device_timestamp;
1372 
1373 	if (skb->len < baselen) {
1374 		tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1375 			 skb->len);
1376 		return -EINVAL;
1377 	}
1378 
1379 	mutex_lock(&local->sta_mtx);
1380 	sta = sta_info_get(sdata, tf->sa);
1381 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1382 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1383 			 tf->sa);
1384 		ret = -EINVAL;
1385 		goto out;
1386 	}
1387 
1388 	params.sta = &sta->sta;
1389 	params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1390 	if (params.status != 0) {
1391 		ret = 0;
1392 		goto call_drv;
1393 	}
1394 
1395 	ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1396 			       skb->len - baselen, false, &elems);
1397 	if (elems.parse_error) {
1398 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1399 		ret = -EINVAL;
1400 		goto out;
1401 	}
1402 
1403 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1404 		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1405 		ret = -EINVAL;
1406 		goto out;
1407 	}
1408 
1409 	/* validate the initiator is set correctly */
1410 	local_initiator =
1411 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1412 	if (local_initiator == sta->sta.tdls_initiator) {
1413 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1414 		ret = -EINVAL;
1415 		goto out;
1416 	}
1417 
1418 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1419 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1420 
1421 	params.tmpl_skb =
1422 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1423 	if (!params.tmpl_skb) {
1424 		ret = -ENOENT;
1425 		goto out;
1426 	}
1427 
1428 call_drv:
1429 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1430 
1431 	tdls_dbg(sdata,
1432 		 "TDLS channel switch response received from %pM status %d\n",
1433 		 tf->sa, params.status);
1434 
1435 out:
1436 	mutex_unlock(&local->sta_mtx);
1437 	dev_kfree_skb_any(params.tmpl_skb);
1438 	return ret;
1439 }
1440 
1441 static int
1442 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1443 					  struct sk_buff *skb)
1444 {
1445 	struct ieee80211_local *local = sdata->local;
1446 	struct ieee802_11_elems elems;
1447 	struct cfg80211_chan_def chandef;
1448 	struct ieee80211_channel *chan;
1449 	enum nl80211_channel_type chan_type;
1450 	int freq;
1451 	u8 target_channel, oper_class;
1452 	bool local_initiator;
1453 	struct sta_info *sta;
1454 	enum ieee80211_band band;
1455 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1456 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1457 	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1458 	struct ieee80211_tdls_ch_sw_params params = {};
1459 	int ret = 0;
1460 
1461 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1462 	params.timestamp = rx_status->device_timestamp;
1463 
1464 	if (skb->len < baselen) {
1465 		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1466 			 skb->len);
1467 		return -EINVAL;
1468 	}
1469 
1470 	target_channel = tf->u.chan_switch_req.target_channel;
1471 	oper_class = tf->u.chan_switch_req.oper_class;
1472 
1473 	/*
1474 	 * We can't easily infer the channel band. The operating class is
1475 	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1476 	 * solution here is to treat channels with number >14 as 5GHz ones,
1477 	 * and specifically check for the (oper_class, channel) combinations
1478 	 * where this doesn't hold. These are thankfully unique according to
1479 	 * IEEE802.11-2012.
1480 	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1481 	 * valid here.
1482 	 */
1483 	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1484 	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1485 	     target_channel < 14)
1486 		band = IEEE80211_BAND_5GHZ;
1487 	else
1488 		band = target_channel < 14 ? IEEE80211_BAND_2GHZ :
1489 					     IEEE80211_BAND_5GHZ;
1490 
1491 	freq = ieee80211_channel_to_frequency(target_channel, band);
1492 	if (freq == 0) {
1493 		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1494 			 target_channel);
1495 		return -EINVAL;
1496 	}
1497 
1498 	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1499 	if (!chan) {
1500 		tdls_dbg(sdata,
1501 			 "Unsupported channel for TDLS chan switch: %d\n",
1502 			 target_channel);
1503 		return -EINVAL;
1504 	}
1505 
1506 	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1507 			       skb->len - baselen, false, &elems);
1508 	if (elems.parse_error) {
1509 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1510 		return -EINVAL;
1511 	}
1512 
1513 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1514 		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1515 		return -EINVAL;
1516 	}
1517 
1518 	mutex_lock(&local->sta_mtx);
1519 	sta = sta_info_get(sdata, tf->sa);
1520 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1521 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1522 			 tf->sa);
1523 		ret = -EINVAL;
1524 		goto out;
1525 	}
1526 
1527 	params.sta = &sta->sta;
1528 
1529 	/* validate the initiator is set correctly */
1530 	local_initiator =
1531 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1532 	if (local_initiator == sta->sta.tdls_initiator) {
1533 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1534 		ret = -EINVAL;
1535 		goto out;
1536 	}
1537 
1538 	if (!sta->sta.ht_cap.ht_supported) {
1539 		chan_type = NL80211_CHAN_NO_HT;
1540 	} else if (!elems.sec_chan_offs) {
1541 		chan_type = NL80211_CHAN_HT20;
1542 	} else {
1543 		switch (elems.sec_chan_offs->sec_chan_offs) {
1544 		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1545 			chan_type = NL80211_CHAN_HT40PLUS;
1546 			break;
1547 		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1548 			chan_type = NL80211_CHAN_HT40MINUS;
1549 			break;
1550 		default:
1551 			chan_type = NL80211_CHAN_HT20;
1552 			break;
1553 		}
1554 	}
1555 
1556 	cfg80211_chandef_create(&chandef, chan, chan_type);
1557 	params.chandef = &chandef;
1558 
1559 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1560 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1561 
1562 	params.tmpl_skb =
1563 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1564 						   &params.ch_sw_tm_ie);
1565 	if (!params.tmpl_skb) {
1566 		ret = -ENOENT;
1567 		goto out;
1568 	}
1569 
1570 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1571 
1572 	tdls_dbg(sdata,
1573 		 "TDLS ch switch request received from %pM ch %d width %d\n",
1574 		 tf->sa, params.chandef->chan->center_freq,
1575 		 params.chandef->width);
1576 out:
1577 	mutex_unlock(&local->sta_mtx);
1578 	dev_kfree_skb_any(params.tmpl_skb);
1579 	return ret;
1580 }
1581 
1582 void ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1583 					   struct sk_buff *skb)
1584 {
1585 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1586 	struct wiphy *wiphy = sdata->local->hw.wiphy;
1587 
1588 	/* make sure the driver supports it */
1589 	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1590 		return;
1591 
1592 	/* we want to access the entire packet */
1593 	if (skb_linearize(skb))
1594 		return;
1595 	/*
1596 	 * The packet/size was already validated by mac80211 Rx path, only look
1597 	 * at the action type.
1598 	 */
1599 	switch (tf->action_code) {
1600 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1601 		ieee80211_process_tdls_channel_switch_req(sdata, skb);
1602 		break;
1603 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1604 		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1605 		break;
1606 	default:
1607 		WARN_ON_ONCE(1);
1608 		return;
1609 	}
1610 }
1611