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1 /*
2  * mac80211 TDLS handling code
3  *
4  * Copyright 2006-2010	Johannes Berg <johannes@sipsolutions.net>
5  * Copyright 2014, Intel Corporation
6  * Copyright 2014  Intel Mobile Communications GmbH
7  * Copyright 2015 - 2016 Intel Deutschland GmbH
8  *
9  * This file is GPLv2 as found in COPYING.
10  */
11 
12 #include <linux/ieee80211.h>
13 #include <linux/log2.h>
14 #include <net/cfg80211.h>
15 #include <linux/rtnetlink.h>
16 #include "ieee80211_i.h"
17 #include "driver-ops.h"
18 #include "rate.h"
19 
20 /* give usermode some time for retries in setting up the TDLS session */
21 #define TDLS_PEER_SETUP_TIMEOUT	(15 * HZ)
22 
ieee80211_tdls_peer_del_work(struct work_struct * wk)23 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
24 {
25 	struct ieee80211_sub_if_data *sdata;
26 	struct ieee80211_local *local;
27 
28 	sdata = container_of(wk, struct ieee80211_sub_if_data,
29 			     u.mgd.tdls_peer_del_work.work);
30 	local = sdata->local;
31 
32 	mutex_lock(&local->mtx);
33 	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
34 		tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
35 		sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
36 		eth_zero_addr(sdata->u.mgd.tdls_peer);
37 	}
38 	mutex_unlock(&local->mtx);
39 }
40 
ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)41 static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
42 					 struct sk_buff *skb)
43 {
44 	struct ieee80211_local *local = sdata->local;
45 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
46 	bool chan_switch = local->hw.wiphy->features &
47 			   NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
48 	bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW) &&
49 			  !ifmgd->tdls_wider_bw_prohibited;
50 	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
51 	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
52 	bool vht = sband && sband->vht_cap.vht_supported;
53 	u8 *pos = (void *)skb_put(skb, 10);
54 
55 	*pos++ = WLAN_EID_EXT_CAPABILITY;
56 	*pos++ = 8; /* len */
57 	*pos++ = 0x0;
58 	*pos++ = 0x0;
59 	*pos++ = 0x0;
60 	*pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
61 	*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
62 	*pos++ = 0;
63 	*pos++ = 0;
64 	*pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
65 }
66 
67 static u8
ieee80211_tdls_add_subband(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb,u16 start,u16 end,u16 spacing)68 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
69 			   struct sk_buff *skb, u16 start, u16 end,
70 			   u16 spacing)
71 {
72 	u8 subband_cnt = 0, ch_cnt = 0;
73 	struct ieee80211_channel *ch;
74 	struct cfg80211_chan_def chandef;
75 	int i, subband_start;
76 	struct wiphy *wiphy = sdata->local->hw.wiphy;
77 
78 	for (i = start; i <= end; i += spacing) {
79 		if (!ch_cnt)
80 			subband_start = i;
81 
82 		ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
83 		if (ch) {
84 			/* we will be active on the channel */
85 			cfg80211_chandef_create(&chandef, ch,
86 						NL80211_CHAN_NO_HT);
87 			if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
88 							  sdata->wdev.iftype)) {
89 				ch_cnt++;
90 				/*
91 				 * check if the next channel is also part of
92 				 * this allowed range
93 				 */
94 				continue;
95 			}
96 		}
97 
98 		/*
99 		 * we've reached the end of a range, with allowed channels
100 		 * found
101 		 */
102 		if (ch_cnt) {
103 			u8 *pos = skb_put(skb, 2);
104 			*pos++ = ieee80211_frequency_to_channel(subband_start);
105 			*pos++ = ch_cnt;
106 
107 			subband_cnt++;
108 			ch_cnt = 0;
109 		}
110 	}
111 
112 	/* all channels in the requested range are allowed - add them here */
113 	if (ch_cnt) {
114 		u8 *pos = skb_put(skb, 2);
115 		*pos++ = ieee80211_frequency_to_channel(subband_start);
116 		*pos++ = ch_cnt;
117 
118 		subband_cnt++;
119 	}
120 
121 	return subband_cnt;
122 }
123 
124 static void
ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)125 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
126 				 struct sk_buff *skb)
127 {
128 	/*
129 	 * Add possible channels for TDLS. These are channels that are allowed
130 	 * to be active.
131 	 */
132 	u8 subband_cnt;
133 	u8 *pos = skb_put(skb, 2);
134 
135 	*pos++ = WLAN_EID_SUPPORTED_CHANNELS;
136 
137 	/*
138 	 * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
139 	 * this doesn't happen in real world scenarios.
140 	 */
141 
142 	/* 2GHz, with 5MHz spacing */
143 	subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
144 
145 	/* 5GHz, with 20MHz spacing */
146 	subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
147 
148 	/* length */
149 	*pos = 2 * subband_cnt;
150 }
151 
ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)152 static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
153 					    struct sk_buff *skb)
154 {
155 	u8 *pos;
156 	u8 op_class;
157 
158 	if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
159 						  &op_class))
160 		return;
161 
162 	pos = skb_put(skb, 4);
163 	*pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
164 	*pos++ = 2; /* len */
165 
166 	*pos++ = op_class;
167 	*pos++ = op_class; /* give current operating class as alternate too */
168 }
169 
ieee80211_tdls_add_bss_coex_ie(struct sk_buff * skb)170 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
171 {
172 	u8 *pos = (void *)skb_put(skb, 3);
173 
174 	*pos++ = WLAN_EID_BSS_COEX_2040;
175 	*pos++ = 1; /* len */
176 
177 	*pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
178 }
179 
ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data * sdata,u16 status_code)180 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
181 					u16 status_code)
182 {
183 	/* The capability will be 0 when sending a failure code */
184 	if (status_code != 0)
185 		return 0;
186 
187 	if (ieee80211_get_sdata_band(sdata) == IEEE80211_BAND_2GHZ) {
188 		return WLAN_CAPABILITY_SHORT_SLOT_TIME |
189 		       WLAN_CAPABILITY_SHORT_PREAMBLE;
190 	}
191 
192 	return 0;
193 }
194 
ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb,const u8 * peer,bool initiator)195 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
196 				       struct sk_buff *skb, const u8 *peer,
197 				       bool initiator)
198 {
199 	struct ieee80211_tdls_lnkie *lnkid;
200 	const u8 *init_addr, *rsp_addr;
201 
202 	if (initiator) {
203 		init_addr = sdata->vif.addr;
204 		rsp_addr = peer;
205 	} else {
206 		init_addr = peer;
207 		rsp_addr = sdata->vif.addr;
208 	}
209 
210 	lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
211 
212 	lnkid->ie_type = WLAN_EID_LINK_ID;
213 	lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
214 
215 	memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
216 	memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
217 	memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
218 }
219 
220 static void
ieee80211_tdls_add_aid(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)221 ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
222 {
223 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
224 	u8 *pos = (void *)skb_put(skb, 4);
225 
226 	*pos++ = WLAN_EID_AID;
227 	*pos++ = 2; /* len */
228 	put_unaligned_le16(ifmgd->aid, pos);
229 }
230 
231 /* translate numbering in the WMM parameter IE to the mac80211 notation */
ieee80211_ac_from_wmm(int ac)232 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
233 {
234 	switch (ac) {
235 	default:
236 		WARN_ON_ONCE(1);
237 	case 0:
238 		return IEEE80211_AC_BE;
239 	case 1:
240 		return IEEE80211_AC_BK;
241 	case 2:
242 		return IEEE80211_AC_VI;
243 	case 3:
244 		return IEEE80211_AC_VO;
245 	}
246 }
247 
ieee80211_wmm_aci_aifsn(int aifsn,bool acm,int aci)248 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
249 {
250 	u8 ret;
251 
252 	ret = aifsn & 0x0f;
253 	if (acm)
254 		ret |= 0x10;
255 	ret |= (aci << 5) & 0x60;
256 	return ret;
257 }
258 
ieee80211_wmm_ecw(u16 cw_min,u16 cw_max)259 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
260 {
261 	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
262 	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
263 }
264 
ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)265 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
266 					    struct sk_buff *skb)
267 {
268 	struct ieee80211_wmm_param_ie *wmm;
269 	struct ieee80211_tx_queue_params *txq;
270 	int i;
271 
272 	wmm = (void *)skb_put(skb, sizeof(*wmm));
273 	memset(wmm, 0, sizeof(*wmm));
274 
275 	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
276 	wmm->len = sizeof(*wmm) - 2;
277 
278 	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
279 	wmm->oui[1] = 0x50;
280 	wmm->oui[2] = 0xf2;
281 	wmm->oui_type = 2; /* WME */
282 	wmm->oui_subtype = 1; /* WME param */
283 	wmm->version = 1; /* WME ver */
284 	wmm->qos_info = 0; /* U-APSD not in use */
285 
286 	/*
287 	 * Use the EDCA parameters defined for the BSS, or default if the AP
288 	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
289 	 */
290 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
291 		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
292 		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
293 							       txq->acm, i);
294 		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
295 		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
296 	}
297 }
298 
299 static void
ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data * sdata,struct sta_info * sta)300 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
301 				   struct sta_info *sta)
302 {
303 	/* IEEE802.11ac-2013 Table E-4 */
304 	u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
305 	struct cfg80211_chan_def uc = sta->tdls_chandef;
306 	enum nl80211_chan_width max_width = ieee80211_sta_cap_chan_bw(sta);
307 	int i;
308 
309 	/* only support upgrading non-narrow channels up to 80Mhz */
310 	if (max_width == NL80211_CHAN_WIDTH_5 ||
311 	    max_width == NL80211_CHAN_WIDTH_10)
312 		return;
313 
314 	if (max_width > NL80211_CHAN_WIDTH_80)
315 		max_width = NL80211_CHAN_WIDTH_80;
316 
317 	if (uc.width >= max_width)
318 		return;
319 	/*
320 	 * Channel usage constrains in the IEEE802.11ac-2013 specification only
321 	 * allow expanding a 20MHz channel to 80MHz in a single way. In
322 	 * addition, there are no 40MHz allowed channels that are not part of
323 	 * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
324 	 */
325 	for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
326 		if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
327 			uc.center_freq1 = centers_80mhz[i];
328 			uc.center_freq2 = 0;
329 			uc.width = NL80211_CHAN_WIDTH_80;
330 			break;
331 		}
332 
333 	if (!uc.center_freq1)
334 		return;
335 
336 	/* proceed to downgrade the chandef until usable or the same */
337 	while (uc.width > max_width ||
338 	       !cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &uc,
339 					      sdata->wdev.iftype))
340 		ieee80211_chandef_downgrade(&uc);
341 
342 	if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
343 		tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
344 			 sta->tdls_chandef.width, uc.width);
345 
346 		/*
347 		 * the station is not yet authorized when BW upgrade is done,
348 		 * locking is not required
349 		 */
350 		sta->tdls_chandef = uc;
351 	}
352 }
353 
354 static void
ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb,const u8 * peer,u8 action_code,bool initiator,const u8 * extra_ies,size_t extra_ies_len)355 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
356 				   struct sk_buff *skb, const u8 *peer,
357 				   u8 action_code, bool initiator,
358 				   const u8 *extra_ies, size_t extra_ies_len)
359 {
360 	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
361 	struct ieee80211_local *local = sdata->local;
362 	struct ieee80211_supported_band *sband;
363 	struct ieee80211_sta_ht_cap ht_cap;
364 	struct ieee80211_sta_vht_cap vht_cap;
365 	struct sta_info *sta = NULL;
366 	size_t offset = 0, noffset;
367 	u8 *pos;
368 
369 	ieee80211_add_srates_ie(sdata, skb, false, band);
370 	ieee80211_add_ext_srates_ie(sdata, skb, false, band);
371 	ieee80211_tdls_add_supp_channels(sdata, skb);
372 
373 	/* add any custom IEs that go before Extended Capabilities */
374 	if (extra_ies_len) {
375 		static const u8 before_ext_cap[] = {
376 			WLAN_EID_SUPP_RATES,
377 			WLAN_EID_COUNTRY,
378 			WLAN_EID_EXT_SUPP_RATES,
379 			WLAN_EID_SUPPORTED_CHANNELS,
380 			WLAN_EID_RSN,
381 		};
382 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
383 					     before_ext_cap,
384 					     ARRAY_SIZE(before_ext_cap),
385 					     offset);
386 		pos = skb_put(skb, noffset - offset);
387 		memcpy(pos, extra_ies + offset, noffset - offset);
388 		offset = noffset;
389 	}
390 
391 	ieee80211_tdls_add_ext_capab(sdata, skb);
392 
393 	/* add the QoS element if we support it */
394 	if (local->hw.queues >= IEEE80211_NUM_ACS &&
395 	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
396 		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
397 
398 	/* add any custom IEs that go before HT capabilities */
399 	if (extra_ies_len) {
400 		static const u8 before_ht_cap[] = {
401 			WLAN_EID_SUPP_RATES,
402 			WLAN_EID_COUNTRY,
403 			WLAN_EID_EXT_SUPP_RATES,
404 			WLAN_EID_SUPPORTED_CHANNELS,
405 			WLAN_EID_RSN,
406 			WLAN_EID_EXT_CAPABILITY,
407 			WLAN_EID_QOS_CAPA,
408 			WLAN_EID_FAST_BSS_TRANSITION,
409 			WLAN_EID_TIMEOUT_INTERVAL,
410 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
411 		};
412 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
413 					     before_ht_cap,
414 					     ARRAY_SIZE(before_ht_cap),
415 					     offset);
416 		pos = skb_put(skb, noffset - offset);
417 		memcpy(pos, extra_ies + offset, noffset - offset);
418 		offset = noffset;
419 	}
420 
421 	mutex_lock(&local->sta_mtx);
422 
423 	/* we should have the peer STA if we're already responding */
424 	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
425 		sta = sta_info_get(sdata, peer);
426 		if (WARN_ON_ONCE(!sta)) {
427 			mutex_unlock(&local->sta_mtx);
428 			return;
429 		}
430 
431 		sta->tdls_chandef = sdata->vif.bss_conf.chandef;
432 	}
433 
434 	ieee80211_tdls_add_oper_classes(sdata, skb);
435 
436 	/*
437 	 * with TDLS we can switch channels, and HT-caps are not necessarily
438 	 * the same on all bands. The specification limits the setup to a
439 	 * single HT-cap, so use the current band for now.
440 	 */
441 	sband = local->hw.wiphy->bands[band];
442 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
443 
444 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
445 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
446 	    ht_cap.ht_supported) {
447 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
448 
449 		/* disable SMPS in TDLS initiator */
450 		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
451 				<< IEEE80211_HT_CAP_SM_PS_SHIFT;
452 
453 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
454 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
455 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
456 		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
457 		/* the peer caps are already intersected with our own */
458 		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
459 
460 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
461 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
462 	}
463 
464 	if (ht_cap.ht_supported &&
465 	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
466 		ieee80211_tdls_add_bss_coex_ie(skb);
467 
468 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
469 
470 	/* add any custom IEs that go before VHT capabilities */
471 	if (extra_ies_len) {
472 		static const u8 before_vht_cap[] = {
473 			WLAN_EID_SUPP_RATES,
474 			WLAN_EID_COUNTRY,
475 			WLAN_EID_EXT_SUPP_RATES,
476 			WLAN_EID_SUPPORTED_CHANNELS,
477 			WLAN_EID_RSN,
478 			WLAN_EID_EXT_CAPABILITY,
479 			WLAN_EID_QOS_CAPA,
480 			WLAN_EID_FAST_BSS_TRANSITION,
481 			WLAN_EID_TIMEOUT_INTERVAL,
482 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
483 			WLAN_EID_MULTI_BAND,
484 		};
485 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
486 					     before_vht_cap,
487 					     ARRAY_SIZE(before_vht_cap),
488 					     offset);
489 		pos = skb_put(skb, noffset - offset);
490 		memcpy(pos, extra_ies + offset, noffset - offset);
491 		offset = noffset;
492 	}
493 
494 	/* build the VHT-cap similarly to the HT-cap */
495 	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
496 	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
497 	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
498 	    vht_cap.vht_supported) {
499 		ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
500 
501 		/* the AID is present only when VHT is implemented */
502 		if (action_code == WLAN_TDLS_SETUP_REQUEST)
503 			ieee80211_tdls_add_aid(sdata, skb);
504 
505 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
506 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
507 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
508 		   vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
509 		/* the peer caps are already intersected with our own */
510 		memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
511 
512 		/* the AID is present only when VHT is implemented */
513 		ieee80211_tdls_add_aid(sdata, skb);
514 
515 		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
516 		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
517 
518 		/*
519 		 * if both peers support WIDER_BW, we can expand the chandef to
520 		 * a wider compatible one, up to 80MHz
521 		 */
522 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
523 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
524 	}
525 
526 	mutex_unlock(&local->sta_mtx);
527 
528 	/* add any remaining IEs */
529 	if (extra_ies_len) {
530 		noffset = extra_ies_len;
531 		pos = skb_put(skb, noffset - offset);
532 		memcpy(pos, extra_ies + offset, noffset - offset);
533 	}
534 
535 }
536 
537 static void
ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb,const u8 * peer,bool initiator,const u8 * extra_ies,size_t extra_ies_len)538 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
539 				 struct sk_buff *skb, const u8 *peer,
540 				 bool initiator, const u8 *extra_ies,
541 				 size_t extra_ies_len)
542 {
543 	struct ieee80211_local *local = sdata->local;
544 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
545 	size_t offset = 0, noffset;
546 	struct sta_info *sta, *ap_sta;
547 	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
548 	u8 *pos;
549 
550 	mutex_lock(&local->sta_mtx);
551 
552 	sta = sta_info_get(sdata, peer);
553 	ap_sta = sta_info_get(sdata, ifmgd->bssid);
554 	if (WARN_ON_ONCE(!sta || !ap_sta)) {
555 		mutex_unlock(&local->sta_mtx);
556 		return;
557 	}
558 
559 	sta->tdls_chandef = sdata->vif.bss_conf.chandef;
560 
561 	/* add any custom IEs that go before the QoS IE */
562 	if (extra_ies_len) {
563 		static const u8 before_qos[] = {
564 			WLAN_EID_RSN,
565 		};
566 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
567 					     before_qos,
568 					     ARRAY_SIZE(before_qos),
569 					     offset);
570 		pos = skb_put(skb, noffset - offset);
571 		memcpy(pos, extra_ies + offset, noffset - offset);
572 		offset = noffset;
573 	}
574 
575 	/* add the QoS param IE if both the peer and we support it */
576 	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
577 		ieee80211_tdls_add_wmm_param_ie(sdata, skb);
578 
579 	/* add any custom IEs that go before HT operation */
580 	if (extra_ies_len) {
581 		static const u8 before_ht_op[] = {
582 			WLAN_EID_RSN,
583 			WLAN_EID_QOS_CAPA,
584 			WLAN_EID_FAST_BSS_TRANSITION,
585 			WLAN_EID_TIMEOUT_INTERVAL,
586 		};
587 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
588 					     before_ht_op,
589 					     ARRAY_SIZE(before_ht_op),
590 					     offset);
591 		pos = skb_put(skb, noffset - offset);
592 		memcpy(pos, extra_ies + offset, noffset - offset);
593 		offset = noffset;
594 	}
595 
596 	/*
597 	 * if HT support is only added in TDLS, we need an HT-operation IE.
598 	 * add the IE as required by IEEE802.11-2012 9.23.3.2.
599 	 */
600 	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
601 		u16 prot = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
602 			   IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
603 			   IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
604 
605 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
606 		ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
607 					   &sdata->vif.bss_conf.chandef, prot,
608 					   true);
609 	}
610 
611 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
612 
613 	/* only include VHT-operation if not on the 2.4GHz band */
614 	if (band != IEEE80211_BAND_2GHZ && sta->sta.vht_cap.vht_supported) {
615 		/*
616 		 * if both peers support WIDER_BW, we can expand the chandef to
617 		 * a wider compatible one, up to 80MHz
618 		 */
619 		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
620 			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
621 
622 		pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
623 		ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
624 					    &sta->tdls_chandef);
625 	}
626 
627 	mutex_unlock(&local->sta_mtx);
628 
629 	/* add any remaining IEs */
630 	if (extra_ies_len) {
631 		noffset = extra_ies_len;
632 		pos = skb_put(skb, noffset - offset);
633 		memcpy(pos, extra_ies + offset, noffset - offset);
634 	}
635 }
636 
637 static void
ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb,const u8 * peer,bool initiator,const u8 * extra_ies,size_t extra_ies_len,u8 oper_class,struct cfg80211_chan_def * chandef)638 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
639 				       struct sk_buff *skb, const u8 *peer,
640 				       bool initiator, const u8 *extra_ies,
641 				       size_t extra_ies_len, u8 oper_class,
642 				       struct cfg80211_chan_def *chandef)
643 {
644 	struct ieee80211_tdls_data *tf;
645 	size_t offset = 0, noffset;
646 	u8 *pos;
647 
648 	if (WARN_ON_ONCE(!chandef))
649 		return;
650 
651 	tf = (void *)skb->data;
652 	tf->u.chan_switch_req.target_channel =
653 		ieee80211_frequency_to_channel(chandef->chan->center_freq);
654 	tf->u.chan_switch_req.oper_class = oper_class;
655 
656 	if (extra_ies_len) {
657 		static const u8 before_lnkie[] = {
658 			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
659 		};
660 		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
661 					     before_lnkie,
662 					     ARRAY_SIZE(before_lnkie),
663 					     offset);
664 		pos = skb_put(skb, noffset - offset);
665 		memcpy(pos, extra_ies + offset, noffset - offset);
666 		offset = noffset;
667 	}
668 
669 	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
670 
671 	/* add any remaining IEs */
672 	if (extra_ies_len) {
673 		noffset = extra_ies_len;
674 		pos = skb_put(skb, noffset - offset);
675 		memcpy(pos, extra_ies + offset, noffset - offset);
676 	}
677 }
678 
679 static void
ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb,const u8 * peer,u16 status_code,bool initiator,const u8 * extra_ies,size_t extra_ies_len)680 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
681 					struct sk_buff *skb, const u8 *peer,
682 					u16 status_code, bool initiator,
683 					const u8 *extra_ies,
684 					size_t extra_ies_len)
685 {
686 	if (status_code == 0)
687 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
688 
689 	if (extra_ies_len)
690 		memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
691 }
692 
ieee80211_tdls_add_ies(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb,const u8 * peer,u8 action_code,u16 status_code,bool initiator,const u8 * extra_ies,size_t extra_ies_len,u8 oper_class,struct cfg80211_chan_def * chandef)693 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
694 				   struct sk_buff *skb, const u8 *peer,
695 				   u8 action_code, u16 status_code,
696 				   bool initiator, const u8 *extra_ies,
697 				   size_t extra_ies_len, u8 oper_class,
698 				   struct cfg80211_chan_def *chandef)
699 {
700 	switch (action_code) {
701 	case WLAN_TDLS_SETUP_REQUEST:
702 	case WLAN_TDLS_SETUP_RESPONSE:
703 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
704 		if (status_code == 0)
705 			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
706 							   action_code,
707 							   initiator,
708 							   extra_ies,
709 							   extra_ies_len);
710 		break;
711 	case WLAN_TDLS_SETUP_CONFIRM:
712 		if (status_code == 0)
713 			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
714 							 initiator, extra_ies,
715 							 extra_ies_len);
716 		break;
717 	case WLAN_TDLS_TEARDOWN:
718 	case WLAN_TDLS_DISCOVERY_REQUEST:
719 		if (extra_ies_len)
720 			memcpy(skb_put(skb, extra_ies_len), extra_ies,
721 			       extra_ies_len);
722 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
723 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
724 		break;
725 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
726 		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
727 						       initiator, extra_ies,
728 						       extra_ies_len,
729 						       oper_class, chandef);
730 		break;
731 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
732 		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
733 							status_code,
734 							initiator, extra_ies,
735 							extra_ies_len);
736 		break;
737 	}
738 
739 }
740 
741 static int
ieee80211_prep_tdls_encap_data(struct wiphy * wiphy,struct net_device * dev,const u8 * peer,u8 action_code,u8 dialog_token,u16 status_code,struct sk_buff * skb)742 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
743 			       const u8 *peer, u8 action_code, u8 dialog_token,
744 			       u16 status_code, struct sk_buff *skb)
745 {
746 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
747 	struct ieee80211_tdls_data *tf;
748 
749 	tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
750 
751 	memcpy(tf->da, peer, ETH_ALEN);
752 	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
753 	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
754 	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
755 
756 	/* network header is after the ethernet header */
757 	skb_set_network_header(skb, ETH_HLEN);
758 
759 	switch (action_code) {
760 	case WLAN_TDLS_SETUP_REQUEST:
761 		tf->category = WLAN_CATEGORY_TDLS;
762 		tf->action_code = WLAN_TDLS_SETUP_REQUEST;
763 
764 		skb_put(skb, sizeof(tf->u.setup_req));
765 		tf->u.setup_req.dialog_token = dialog_token;
766 		tf->u.setup_req.capability =
767 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
768 								 status_code));
769 		break;
770 	case WLAN_TDLS_SETUP_RESPONSE:
771 		tf->category = WLAN_CATEGORY_TDLS;
772 		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
773 
774 		skb_put(skb, sizeof(tf->u.setup_resp));
775 		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
776 		tf->u.setup_resp.dialog_token = dialog_token;
777 		tf->u.setup_resp.capability =
778 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
779 								 status_code));
780 		break;
781 	case WLAN_TDLS_SETUP_CONFIRM:
782 		tf->category = WLAN_CATEGORY_TDLS;
783 		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
784 
785 		skb_put(skb, sizeof(tf->u.setup_cfm));
786 		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
787 		tf->u.setup_cfm.dialog_token = dialog_token;
788 		break;
789 	case WLAN_TDLS_TEARDOWN:
790 		tf->category = WLAN_CATEGORY_TDLS;
791 		tf->action_code = WLAN_TDLS_TEARDOWN;
792 
793 		skb_put(skb, sizeof(tf->u.teardown));
794 		tf->u.teardown.reason_code = cpu_to_le16(status_code);
795 		break;
796 	case WLAN_TDLS_DISCOVERY_REQUEST:
797 		tf->category = WLAN_CATEGORY_TDLS;
798 		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
799 
800 		skb_put(skb, sizeof(tf->u.discover_req));
801 		tf->u.discover_req.dialog_token = dialog_token;
802 		break;
803 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
804 		tf->category = WLAN_CATEGORY_TDLS;
805 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
806 
807 		skb_put(skb, sizeof(tf->u.chan_switch_req));
808 		break;
809 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
810 		tf->category = WLAN_CATEGORY_TDLS;
811 		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
812 
813 		skb_put(skb, sizeof(tf->u.chan_switch_resp));
814 		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
815 		break;
816 	default:
817 		return -EINVAL;
818 	}
819 
820 	return 0;
821 }
822 
823 static int
ieee80211_prep_tdls_direct(struct wiphy * wiphy,struct net_device * dev,const u8 * peer,u8 action_code,u8 dialog_token,u16 status_code,struct sk_buff * skb)824 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
825 			   const u8 *peer, u8 action_code, u8 dialog_token,
826 			   u16 status_code, struct sk_buff *skb)
827 {
828 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
829 	struct ieee80211_mgmt *mgmt;
830 
831 	mgmt = (void *)skb_put(skb, 24);
832 	memset(mgmt, 0, 24);
833 	memcpy(mgmt->da, peer, ETH_ALEN);
834 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
835 	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
836 
837 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
838 					  IEEE80211_STYPE_ACTION);
839 
840 	switch (action_code) {
841 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
842 		skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
843 		mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
844 		mgmt->u.action.u.tdls_discover_resp.action_code =
845 			WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
846 		mgmt->u.action.u.tdls_discover_resp.dialog_token =
847 			dialog_token;
848 		mgmt->u.action.u.tdls_discover_resp.capability =
849 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
850 								 status_code));
851 		break;
852 	default:
853 		return -EINVAL;
854 	}
855 
856 	return 0;
857 }
858 
859 static struct sk_buff *
ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data * sdata,const u8 * peer,u8 action_code,u8 dialog_token,u16 status_code,bool initiator,const u8 * extra_ies,size_t extra_ies_len,u8 oper_class,struct cfg80211_chan_def * chandef)860 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
861 				      const u8 *peer, u8 action_code,
862 				      u8 dialog_token, u16 status_code,
863 				      bool initiator, const u8 *extra_ies,
864 				      size_t extra_ies_len, u8 oper_class,
865 				      struct cfg80211_chan_def *chandef)
866 {
867 	struct ieee80211_local *local = sdata->local;
868 	struct sk_buff *skb;
869 	int ret;
870 
871 	skb = netdev_alloc_skb(sdata->dev,
872 			       local->hw.extra_tx_headroom +
873 			       max(sizeof(struct ieee80211_mgmt),
874 				   sizeof(struct ieee80211_tdls_data)) +
875 			       50 + /* supported rates */
876 			       10 + /* ext capab */
877 			       26 + /* max(WMM-info, WMM-param) */
878 			       2 + max(sizeof(struct ieee80211_ht_cap),
879 				       sizeof(struct ieee80211_ht_operation)) +
880 			       2 + max(sizeof(struct ieee80211_vht_cap),
881 				       sizeof(struct ieee80211_vht_operation)) +
882 			       50 + /* supported channels */
883 			       3 + /* 40/20 BSS coex */
884 			       4 + /* AID */
885 			       4 + /* oper classes */
886 			       extra_ies_len +
887 			       sizeof(struct ieee80211_tdls_lnkie));
888 	if (!skb)
889 		return NULL;
890 
891 	skb_reserve(skb, local->hw.extra_tx_headroom);
892 
893 	switch (action_code) {
894 	case WLAN_TDLS_SETUP_REQUEST:
895 	case WLAN_TDLS_SETUP_RESPONSE:
896 	case WLAN_TDLS_SETUP_CONFIRM:
897 	case WLAN_TDLS_TEARDOWN:
898 	case WLAN_TDLS_DISCOVERY_REQUEST:
899 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
900 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
901 		ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
902 						     sdata->dev, peer,
903 						     action_code, dialog_token,
904 						     status_code, skb);
905 		break;
906 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
907 		ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
908 						 peer, action_code,
909 						 dialog_token, status_code,
910 						 skb);
911 		break;
912 	default:
913 		ret = -ENOTSUPP;
914 		break;
915 	}
916 
917 	if (ret < 0)
918 		goto fail;
919 
920 	ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
921 			       initiator, extra_ies, extra_ies_len, oper_class,
922 			       chandef);
923 	return skb;
924 
925 fail:
926 	dev_kfree_skb(skb);
927 	return NULL;
928 }
929 
930 static int
ieee80211_tdls_prep_mgmt_packet(struct wiphy * wiphy,struct net_device * dev,const u8 * peer,u8 action_code,u8 dialog_token,u16 status_code,u32 peer_capability,bool initiator,const u8 * extra_ies,size_t extra_ies_len,u8 oper_class,struct cfg80211_chan_def * chandef)931 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
932 				const u8 *peer, u8 action_code, u8 dialog_token,
933 				u16 status_code, u32 peer_capability,
934 				bool initiator, const u8 *extra_ies,
935 				size_t extra_ies_len, u8 oper_class,
936 				struct cfg80211_chan_def *chandef)
937 {
938 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
939 	struct sk_buff *skb = NULL;
940 	struct sta_info *sta;
941 	u32 flags = 0;
942 	int ret = 0;
943 
944 	rcu_read_lock();
945 	sta = sta_info_get(sdata, peer);
946 
947 	/* infer the initiator if we can, to support old userspace */
948 	switch (action_code) {
949 	case WLAN_TDLS_SETUP_REQUEST:
950 		if (sta) {
951 			set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
952 			sta->sta.tdls_initiator = false;
953 		}
954 		/* fall-through */
955 	case WLAN_TDLS_SETUP_CONFIRM:
956 	case WLAN_TDLS_DISCOVERY_REQUEST:
957 		initiator = true;
958 		break;
959 	case WLAN_TDLS_SETUP_RESPONSE:
960 		/*
961 		 * In some testing scenarios, we send a request and response.
962 		 * Make the last packet sent take effect for the initiator
963 		 * value.
964 		 */
965 		if (sta) {
966 			clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
967 			sta->sta.tdls_initiator = true;
968 		}
969 		/* fall-through */
970 	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
971 		initiator = false;
972 		break;
973 	case WLAN_TDLS_TEARDOWN:
974 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
975 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
976 		/* any value is ok */
977 		break;
978 	default:
979 		ret = -ENOTSUPP;
980 		break;
981 	}
982 
983 	if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
984 		initiator = true;
985 
986 	rcu_read_unlock();
987 	if (ret < 0)
988 		goto fail;
989 
990 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
991 						    dialog_token, status_code,
992 						    initiator, extra_ies,
993 						    extra_ies_len, oper_class,
994 						    chandef);
995 	if (!skb) {
996 		ret = -EINVAL;
997 		goto fail;
998 	}
999 
1000 	if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
1001 		ieee80211_tx_skb(sdata, skb);
1002 		return 0;
1003 	}
1004 
1005 	/*
1006 	 * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
1007 	 * we should default to AC_VI.
1008 	 */
1009 	switch (action_code) {
1010 	case WLAN_TDLS_SETUP_REQUEST:
1011 	case WLAN_TDLS_SETUP_RESPONSE:
1012 		skb_set_queue_mapping(skb, IEEE80211_AC_BK);
1013 		skb->priority = 2;
1014 		break;
1015 	default:
1016 		skb_set_queue_mapping(skb, IEEE80211_AC_VI);
1017 		skb->priority = 5;
1018 		break;
1019 	}
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);
1058 	local_bh_enable();
1059 
1060 	return ret;
1061 
1062 fail:
1063 	dev_kfree_skb(skb);
1064 	return ret;
1065 }
1066 
1067 static int
ieee80211_tdls_mgmt_setup(struct wiphy * wiphy,struct net_device * dev,const u8 * peer,u8 action_code,u8 dialog_token,u16 status_code,u32 peer_capability,bool initiator,const u8 * extra_ies,size_t extra_ies_len)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
ieee80211_tdls_mgmt_teardown(struct wiphy * wiphy,struct net_device * dev,const u8 * peer,u8 action_code,u8 dialog_token,u16 status_code,u32 peer_capability,bool initiator,const u8 * extra_ies,size_t extra_ies_len)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 
ieee80211_tdls_mgmt(struct wiphy * wiphy,struct net_device * dev,const u8 * peer,u8 action_code,u8 dialog_token,u16 status_code,u32 peer_capability,bool initiator,const u8 * extra_ies,size_t extra_ies_len)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 
iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data * sdata,struct sta_info * sta)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 
iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data * sdata)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
iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data * sdata,struct sta_info * sta)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 
ieee80211_tdls_oper(struct wiphy * wiphy,struct net_device * dev,const u8 * peer,enum nl80211_tdls_operation oper)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 
ieee80211_tdls_oper_request(struct ieee80211_vif * vif,const u8 * peer,enum nl80211_tdls_operation oper,u16 reason_code,gfp_t gfp)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
iee80211_tdls_add_ch_switch_timing(u8 * buf,u16 switch_time,u16 switch_timeout)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 */
ieee80211_tdls_find_sw_timing_ie(struct sk_buff * skb)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 *
ieee80211_tdls_ch_sw_tmpl_get(struct sta_info * sta,u8 oper_class,struct cfg80211_chan_def * chandef,u32 * ch_sw_tm_ie_offset)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
ieee80211_tdls_channel_switch(struct wiphy * wiphy,struct net_device * dev,const u8 * addr,u8 oper_class,struct cfg80211_chan_def * chandef)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 	mutex_lock(&local->sta_mtx);
1570 	sta = sta_info_get(sdata, addr);
1571 	if (!sta) {
1572 		tdls_dbg(sdata,
1573 			 "Invalid TDLS peer %pM for channel switch request\n",
1574 			 addr);
1575 		ret = -ENOENT;
1576 		goto out;
1577 	}
1578 
1579 	if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1580 		tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1581 			 addr);
1582 		ret = -ENOTSUPP;
1583 		goto out;
1584 	}
1585 
1586 	skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1587 					    &ch_sw_tm_ie);
1588 	if (!skb) {
1589 		ret = -ENOENT;
1590 		goto out;
1591 	}
1592 
1593 	ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1594 				      chandef, skb, ch_sw_tm_ie);
1595 	if (!ret)
1596 		set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1597 
1598 out:
1599 	mutex_unlock(&local->sta_mtx);
1600 	dev_kfree_skb_any(skb);
1601 	return ret;
1602 }
1603 
1604 void
ieee80211_tdls_cancel_channel_switch(struct wiphy * wiphy,struct net_device * dev,const u8 * addr)1605 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1606 				     struct net_device *dev,
1607 				     const u8 *addr)
1608 {
1609 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1610 	struct ieee80211_local *local = sdata->local;
1611 	struct sta_info *sta;
1612 
1613 	mutex_lock(&local->sta_mtx);
1614 	sta = sta_info_get(sdata, addr);
1615 	if (!sta) {
1616 		tdls_dbg(sdata,
1617 			 "Invalid TDLS peer %pM for channel switch cancel\n",
1618 			 addr);
1619 		goto out;
1620 	}
1621 
1622 	if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1623 		tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1624 			 addr);
1625 		goto out;
1626 	}
1627 
1628 	drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1629 	clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1630 
1631 out:
1632 	mutex_unlock(&local->sta_mtx);
1633 }
1634 
1635 static struct sk_buff *
ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info * sta,u32 * ch_sw_tm_ie_offset)1636 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1637 				   u32 *ch_sw_tm_ie_offset)
1638 {
1639 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1640 	struct sk_buff *skb;
1641 	u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1642 
1643 	/* initial timing are always zero in the template */
1644 	iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1645 
1646 	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1647 					WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1648 					0, 0, !sta->sta.tdls_initiator,
1649 					extra_ies, sizeof(extra_ies), 0, NULL);
1650 	if (!skb)
1651 		return NULL;
1652 
1653 	skb = ieee80211_build_data_template(sdata, skb, 0);
1654 	if (IS_ERR(skb)) {
1655 		tdls_dbg(sdata,
1656 			 "Failed building TDLS channel switch resp frame\n");
1657 		return NULL;
1658 	}
1659 
1660 	if (ch_sw_tm_ie_offset) {
1661 		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1662 
1663 		if (!tm_ie) {
1664 			tdls_dbg(sdata,
1665 				 "No switch timing IE in TDLS switch resp\n");
1666 			dev_kfree_skb_any(skb);
1667 			return NULL;
1668 		}
1669 
1670 		*ch_sw_tm_ie_offset = tm_ie - skb->data;
1671 	}
1672 
1673 	tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1674 		 sta->sta.addr);
1675 	return skb;
1676 }
1677 
1678 static int
ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)1679 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1680 					   struct sk_buff *skb)
1681 {
1682 	struct ieee80211_local *local = sdata->local;
1683 	struct ieee802_11_elems elems;
1684 	struct sta_info *sta;
1685 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1686 	bool local_initiator;
1687 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1688 	int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1689 	struct ieee80211_tdls_ch_sw_params params = {};
1690 	int ret;
1691 
1692 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1693 	params.timestamp = rx_status->device_timestamp;
1694 
1695 	if (skb->len < baselen) {
1696 		tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1697 			 skb->len);
1698 		return -EINVAL;
1699 	}
1700 
1701 	mutex_lock(&local->sta_mtx);
1702 	sta = sta_info_get(sdata, tf->sa);
1703 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1704 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1705 			 tf->sa);
1706 		ret = -EINVAL;
1707 		goto out;
1708 	}
1709 
1710 	params.sta = &sta->sta;
1711 	params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1712 	if (params.status != 0) {
1713 		ret = 0;
1714 		goto call_drv;
1715 	}
1716 
1717 	ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1718 			       skb->len - baselen, false, &elems);
1719 	if (elems.parse_error) {
1720 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1721 		ret = -EINVAL;
1722 		goto out;
1723 	}
1724 
1725 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1726 		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1727 		ret = -EINVAL;
1728 		goto out;
1729 	}
1730 
1731 	/* validate the initiator is set correctly */
1732 	local_initiator =
1733 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1734 	if (local_initiator == sta->sta.tdls_initiator) {
1735 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1736 		ret = -EINVAL;
1737 		goto out;
1738 	}
1739 
1740 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1741 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1742 
1743 	params.tmpl_skb =
1744 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1745 	if (!params.tmpl_skb) {
1746 		ret = -ENOENT;
1747 		goto out;
1748 	}
1749 
1750 call_drv:
1751 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1752 
1753 	tdls_dbg(sdata,
1754 		 "TDLS channel switch response received from %pM status %d\n",
1755 		 tf->sa, params.status);
1756 
1757 out:
1758 	mutex_unlock(&local->sta_mtx);
1759 	dev_kfree_skb_any(params.tmpl_skb);
1760 	return ret;
1761 }
1762 
1763 static int
ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)1764 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1765 					  struct sk_buff *skb)
1766 {
1767 	struct ieee80211_local *local = sdata->local;
1768 	struct ieee802_11_elems elems;
1769 	struct cfg80211_chan_def chandef;
1770 	struct ieee80211_channel *chan;
1771 	enum nl80211_channel_type chan_type;
1772 	int freq;
1773 	u8 target_channel, oper_class;
1774 	bool local_initiator;
1775 	struct sta_info *sta;
1776 	enum ieee80211_band band;
1777 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1778 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1779 	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1780 	struct ieee80211_tdls_ch_sw_params params = {};
1781 	int ret = 0;
1782 
1783 	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1784 	params.timestamp = rx_status->device_timestamp;
1785 
1786 	if (skb->len < baselen) {
1787 		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1788 			 skb->len);
1789 		return -EINVAL;
1790 	}
1791 
1792 	target_channel = tf->u.chan_switch_req.target_channel;
1793 	oper_class = tf->u.chan_switch_req.oper_class;
1794 
1795 	/*
1796 	 * We can't easily infer the channel band. The operating class is
1797 	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1798 	 * solution here is to treat channels with number >14 as 5GHz ones,
1799 	 * and specifically check for the (oper_class, channel) combinations
1800 	 * where this doesn't hold. These are thankfully unique according to
1801 	 * IEEE802.11-2012.
1802 	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1803 	 * valid here.
1804 	 */
1805 	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1806 	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1807 	     target_channel < 14)
1808 		band = IEEE80211_BAND_5GHZ;
1809 	else
1810 		band = target_channel < 14 ? IEEE80211_BAND_2GHZ :
1811 					     IEEE80211_BAND_5GHZ;
1812 
1813 	freq = ieee80211_channel_to_frequency(target_channel, band);
1814 	if (freq == 0) {
1815 		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1816 			 target_channel);
1817 		return -EINVAL;
1818 	}
1819 
1820 	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1821 	if (!chan) {
1822 		tdls_dbg(sdata,
1823 			 "Unsupported channel for TDLS chan switch: %d\n",
1824 			 target_channel);
1825 		return -EINVAL;
1826 	}
1827 
1828 	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1829 			       skb->len - baselen, false, &elems);
1830 	if (elems.parse_error) {
1831 		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1832 		return -EINVAL;
1833 	}
1834 
1835 	if (!elems.ch_sw_timing || !elems.lnk_id) {
1836 		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1837 		return -EINVAL;
1838 	}
1839 
1840 	if (!elems.sec_chan_offs) {
1841 		chan_type = NL80211_CHAN_HT20;
1842 	} else {
1843 		switch (elems.sec_chan_offs->sec_chan_offs) {
1844 		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1845 			chan_type = NL80211_CHAN_HT40PLUS;
1846 			break;
1847 		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1848 			chan_type = NL80211_CHAN_HT40MINUS;
1849 			break;
1850 		default:
1851 			chan_type = NL80211_CHAN_HT20;
1852 			break;
1853 		}
1854 	}
1855 
1856 	cfg80211_chandef_create(&chandef, chan, chan_type);
1857 
1858 	/* we will be active on the TDLS link */
1859 	if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1860 					   sdata->wdev.iftype)) {
1861 		tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1862 		return -EINVAL;
1863 	}
1864 
1865 	mutex_lock(&local->sta_mtx);
1866 	sta = sta_info_get(sdata, tf->sa);
1867 	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1868 		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1869 			 tf->sa);
1870 		ret = -EINVAL;
1871 		goto out;
1872 	}
1873 
1874 	params.sta = &sta->sta;
1875 
1876 	/* validate the initiator is set correctly */
1877 	local_initiator =
1878 		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1879 	if (local_initiator == sta->sta.tdls_initiator) {
1880 		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1881 		ret = -EINVAL;
1882 		goto out;
1883 	}
1884 
1885 	/* peer should have known better */
1886 	if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1887 	    elems.sec_chan_offs->sec_chan_offs) {
1888 		tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1889 		ret = -ENOTSUPP;
1890 		goto out;
1891 	}
1892 
1893 	params.chandef = &chandef;
1894 	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1895 	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1896 
1897 	params.tmpl_skb =
1898 		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1899 						   &params.ch_sw_tm_ie);
1900 	if (!params.tmpl_skb) {
1901 		ret = -ENOENT;
1902 		goto out;
1903 	}
1904 
1905 	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1906 
1907 	tdls_dbg(sdata,
1908 		 "TDLS ch switch request received from %pM ch %d width %d\n",
1909 		 tf->sa, params.chandef->chan->center_freq,
1910 		 params.chandef->width);
1911 out:
1912 	mutex_unlock(&local->sta_mtx);
1913 	dev_kfree_skb_any(params.tmpl_skb);
1914 	return ret;
1915 }
1916 
1917 static void
ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)1918 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1919 				      struct sk_buff *skb)
1920 {
1921 	struct ieee80211_tdls_data *tf = (void *)skb->data;
1922 	struct wiphy *wiphy = sdata->local->hw.wiphy;
1923 
1924 	ASSERT_RTNL();
1925 
1926 	/* make sure the driver supports it */
1927 	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1928 		return;
1929 
1930 	/* we want to access the entire packet */
1931 	if (skb_linearize(skb))
1932 		return;
1933 	/*
1934 	 * The packet/size was already validated by mac80211 Rx path, only look
1935 	 * at the action type.
1936 	 */
1937 	switch (tf->action_code) {
1938 	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1939 		ieee80211_process_tdls_channel_switch_req(sdata, skb);
1940 		break;
1941 	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1942 		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1943 		break;
1944 	default:
1945 		WARN_ON_ONCE(1);
1946 		return;
1947 	}
1948 }
1949 
ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data * sdata)1950 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1951 {
1952 	struct sta_info *sta;
1953 	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1954 
1955 	rcu_read_lock();
1956 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1957 		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1958 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1959 			continue;
1960 
1961 		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1962 					    NL80211_TDLS_TEARDOWN, reason,
1963 					    GFP_ATOMIC);
1964 	}
1965 	rcu_read_unlock();
1966 }
1967 
ieee80211_tdls_chsw_work(struct work_struct * wk)1968 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1969 {
1970 	struct ieee80211_local *local =
1971 		container_of(wk, struct ieee80211_local, tdls_chsw_work);
1972 	struct ieee80211_sub_if_data *sdata;
1973 	struct sk_buff *skb;
1974 	struct ieee80211_tdls_data *tf;
1975 
1976 	rtnl_lock();
1977 	while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1978 		tf = (struct ieee80211_tdls_data *)skb->data;
1979 		list_for_each_entry(sdata, &local->interfaces, list) {
1980 			if (!ieee80211_sdata_running(sdata) ||
1981 			    sdata->vif.type != NL80211_IFTYPE_STATION ||
1982 			    !ether_addr_equal(tf->da, sdata->vif.addr))
1983 				continue;
1984 
1985 			ieee80211_process_tdls_channel_switch(sdata, skb);
1986 			break;
1987 		}
1988 
1989 		kfree_skb(skb);
1990 	}
1991 	rtnl_unlock();
1992 }
1993 
ieee80211_tdls_handle_disconnect(struct ieee80211_sub_if_data * sdata,const u8 * peer,u16 reason)1994 void ieee80211_tdls_handle_disconnect(struct ieee80211_sub_if_data *sdata,
1995 				      const u8 *peer, u16 reason)
1996 {
1997 	struct ieee80211_sta *sta;
1998 
1999 	rcu_read_lock();
2000 	sta = ieee80211_find_sta(&sdata->vif, peer);
2001 	if (!sta || !sta->tdls) {
2002 		rcu_read_unlock();
2003 		return;
2004 	}
2005 	rcu_read_unlock();
2006 
2007 	tdls_dbg(sdata, "disconnected from TDLS peer %pM (Reason: %u=%s)\n",
2008 		 peer, reason,
2009 		 ieee80211_get_reason_code_string(reason));
2010 
2011 	ieee80211_tdls_oper_request(&sdata->vif, peer,
2012 				    NL80211_TDLS_TEARDOWN,
2013 				    WLAN_REASON_TDLS_TEARDOWN_UNREACHABLE,
2014 				    GFP_ATOMIC);
2015 }
2016