xref: /openbmc/linux/net/wireless/util.c (revision ae40e94f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Wireless utility functions
4  *
5  * Copyright 2007-2009	Johannes Berg <johannes@sipsolutions.net>
6  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  * Copyright 2017	Intel Deutschland GmbH
8  * Copyright (C) 2018-2019 Intel Corporation
9  */
10 #include <linux/export.h>
11 #include <linux/bitops.h>
12 #include <linux/etherdevice.h>
13 #include <linux/slab.h>
14 #include <linux/ieee80211.h>
15 #include <net/cfg80211.h>
16 #include <net/ip.h>
17 #include <net/dsfield.h>
18 #include <linux/if_vlan.h>
19 #include <linux/mpls.h>
20 #include <linux/gcd.h>
21 #include <linux/bitfield.h>
22 #include <linux/nospec.h>
23 #include "core.h"
24 #include "rdev-ops.h"
25 
26 
27 struct ieee80211_rate *
28 ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
29 			    u32 basic_rates, int bitrate)
30 {
31 	struct ieee80211_rate *result = &sband->bitrates[0];
32 	int i;
33 
34 	for (i = 0; i < sband->n_bitrates; i++) {
35 		if (!(basic_rates & BIT(i)))
36 			continue;
37 		if (sband->bitrates[i].bitrate > bitrate)
38 			continue;
39 		result = &sband->bitrates[i];
40 	}
41 
42 	return result;
43 }
44 EXPORT_SYMBOL(ieee80211_get_response_rate);
45 
46 u32 ieee80211_mandatory_rates(struct ieee80211_supported_band *sband,
47 			      enum nl80211_bss_scan_width scan_width)
48 {
49 	struct ieee80211_rate *bitrates;
50 	u32 mandatory_rates = 0;
51 	enum ieee80211_rate_flags mandatory_flag;
52 	int i;
53 
54 	if (WARN_ON(!sband))
55 		return 1;
56 
57 	if (sband->band == NL80211_BAND_2GHZ) {
58 		if (scan_width == NL80211_BSS_CHAN_WIDTH_5 ||
59 		    scan_width == NL80211_BSS_CHAN_WIDTH_10)
60 			mandatory_flag = IEEE80211_RATE_MANDATORY_G;
61 		else
62 			mandatory_flag = IEEE80211_RATE_MANDATORY_B;
63 	} else {
64 		mandatory_flag = IEEE80211_RATE_MANDATORY_A;
65 	}
66 
67 	bitrates = sband->bitrates;
68 	for (i = 0; i < sband->n_bitrates; i++)
69 		if (bitrates[i].flags & mandatory_flag)
70 			mandatory_rates |= BIT(i);
71 	return mandatory_rates;
72 }
73 EXPORT_SYMBOL(ieee80211_mandatory_rates);
74 
75 int ieee80211_channel_to_frequency(int chan, enum nl80211_band band)
76 {
77 	/* see 802.11 17.3.8.3.2 and Annex J
78 	 * there are overlapping channel numbers in 5GHz and 2GHz bands */
79 	if (chan <= 0)
80 		return 0; /* not supported */
81 	switch (band) {
82 	case NL80211_BAND_2GHZ:
83 		if (chan == 14)
84 			return 2484;
85 		else if (chan < 14)
86 			return 2407 + chan * 5;
87 		break;
88 	case NL80211_BAND_5GHZ:
89 		if (chan >= 182 && chan <= 196)
90 			return 4000 + chan * 5;
91 		else
92 			return 5000 + chan * 5;
93 		break;
94 	case NL80211_BAND_60GHZ:
95 		if (chan < 7)
96 			return 56160 + chan * 2160;
97 		break;
98 	default:
99 		;
100 	}
101 	return 0; /* not supported */
102 }
103 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
104 
105 int ieee80211_frequency_to_channel(int freq)
106 {
107 	/* see 802.11 17.3.8.3.2 and Annex J */
108 	if (freq == 2484)
109 		return 14;
110 	else if (freq < 2484)
111 		return (freq - 2407) / 5;
112 	else if (freq >= 4910 && freq <= 4980)
113 		return (freq - 4000) / 5;
114 	else if (freq <= 45000) /* DMG band lower limit */
115 		return (freq - 5000) / 5;
116 	else if (freq >= 58320 && freq <= 70200)
117 		return (freq - 56160) / 2160;
118 	else
119 		return 0;
120 }
121 EXPORT_SYMBOL(ieee80211_frequency_to_channel);
122 
123 struct ieee80211_channel *ieee80211_get_channel(struct wiphy *wiphy, int freq)
124 {
125 	enum nl80211_band band;
126 	struct ieee80211_supported_band *sband;
127 	int i;
128 
129 	for (band = 0; band < NUM_NL80211_BANDS; band++) {
130 		sband = wiphy->bands[band];
131 
132 		if (!sband)
133 			continue;
134 
135 		for (i = 0; i < sband->n_channels; i++) {
136 			if (sband->channels[i].center_freq == freq)
137 				return &sband->channels[i];
138 		}
139 	}
140 
141 	return NULL;
142 }
143 EXPORT_SYMBOL(ieee80211_get_channel);
144 
145 static void set_mandatory_flags_band(struct ieee80211_supported_band *sband)
146 {
147 	int i, want;
148 
149 	switch (sband->band) {
150 	case NL80211_BAND_5GHZ:
151 		want = 3;
152 		for (i = 0; i < sband->n_bitrates; i++) {
153 			if (sband->bitrates[i].bitrate == 60 ||
154 			    sband->bitrates[i].bitrate == 120 ||
155 			    sband->bitrates[i].bitrate == 240) {
156 				sband->bitrates[i].flags |=
157 					IEEE80211_RATE_MANDATORY_A;
158 				want--;
159 			}
160 		}
161 		WARN_ON(want);
162 		break;
163 	case NL80211_BAND_2GHZ:
164 		want = 7;
165 		for (i = 0; i < sband->n_bitrates; i++) {
166 			switch (sband->bitrates[i].bitrate) {
167 			case 10:
168 			case 20:
169 			case 55:
170 			case 110:
171 				sband->bitrates[i].flags |=
172 					IEEE80211_RATE_MANDATORY_B |
173 					IEEE80211_RATE_MANDATORY_G;
174 				want--;
175 				break;
176 			case 60:
177 			case 120:
178 			case 240:
179 				sband->bitrates[i].flags |=
180 					IEEE80211_RATE_MANDATORY_G;
181 				want--;
182 				/* fall through */
183 			default:
184 				sband->bitrates[i].flags |=
185 					IEEE80211_RATE_ERP_G;
186 				break;
187 			}
188 		}
189 		WARN_ON(want != 0 && want != 3);
190 		break;
191 	case NL80211_BAND_60GHZ:
192 		/* check for mandatory HT MCS 1..4 */
193 		WARN_ON(!sband->ht_cap.ht_supported);
194 		WARN_ON((sband->ht_cap.mcs.rx_mask[0] & 0x1e) != 0x1e);
195 		break;
196 	case NUM_NL80211_BANDS:
197 	default:
198 		WARN_ON(1);
199 		break;
200 	}
201 }
202 
203 void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
204 {
205 	enum nl80211_band band;
206 
207 	for (band = 0; band < NUM_NL80211_BANDS; band++)
208 		if (wiphy->bands[band])
209 			set_mandatory_flags_band(wiphy->bands[band]);
210 }
211 
212 bool cfg80211_supported_cipher_suite(struct wiphy *wiphy, u32 cipher)
213 {
214 	int i;
215 	for (i = 0; i < wiphy->n_cipher_suites; i++)
216 		if (cipher == wiphy->cipher_suites[i])
217 			return true;
218 	return false;
219 }
220 
221 int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
222 				   struct key_params *params, int key_idx,
223 				   bool pairwise, const u8 *mac_addr)
224 {
225 	if (key_idx < 0 || key_idx > 5)
226 		return -EINVAL;
227 
228 	if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
229 		return -EINVAL;
230 
231 	if (pairwise && !mac_addr)
232 		return -EINVAL;
233 
234 	switch (params->cipher) {
235 	case WLAN_CIPHER_SUITE_TKIP:
236 	case WLAN_CIPHER_SUITE_CCMP:
237 	case WLAN_CIPHER_SUITE_CCMP_256:
238 	case WLAN_CIPHER_SUITE_GCMP:
239 	case WLAN_CIPHER_SUITE_GCMP_256:
240 		/* Disallow pairwise keys with non-zero index unless it's WEP
241 		 * or a vendor specific cipher (because current deployments use
242 		 * pairwise WEP keys with non-zero indices and for vendor
243 		 * specific ciphers this should be validated in the driver or
244 		 * hardware level - but 802.11i clearly specifies to use zero)
245 		 */
246 		if (pairwise && key_idx)
247 			return -EINVAL;
248 		break;
249 	case WLAN_CIPHER_SUITE_AES_CMAC:
250 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
251 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
252 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
253 		/* Disallow BIP (group-only) cipher as pairwise cipher */
254 		if (pairwise)
255 			return -EINVAL;
256 		if (key_idx < 4)
257 			return -EINVAL;
258 		break;
259 	case WLAN_CIPHER_SUITE_WEP40:
260 	case WLAN_CIPHER_SUITE_WEP104:
261 		if (key_idx > 3)
262 			return -EINVAL;
263 	default:
264 		break;
265 	}
266 
267 	switch (params->cipher) {
268 	case WLAN_CIPHER_SUITE_WEP40:
269 		if (params->key_len != WLAN_KEY_LEN_WEP40)
270 			return -EINVAL;
271 		break;
272 	case WLAN_CIPHER_SUITE_TKIP:
273 		if (params->key_len != WLAN_KEY_LEN_TKIP)
274 			return -EINVAL;
275 		break;
276 	case WLAN_CIPHER_SUITE_CCMP:
277 		if (params->key_len != WLAN_KEY_LEN_CCMP)
278 			return -EINVAL;
279 		break;
280 	case WLAN_CIPHER_SUITE_CCMP_256:
281 		if (params->key_len != WLAN_KEY_LEN_CCMP_256)
282 			return -EINVAL;
283 		break;
284 	case WLAN_CIPHER_SUITE_GCMP:
285 		if (params->key_len != WLAN_KEY_LEN_GCMP)
286 			return -EINVAL;
287 		break;
288 	case WLAN_CIPHER_SUITE_GCMP_256:
289 		if (params->key_len != WLAN_KEY_LEN_GCMP_256)
290 			return -EINVAL;
291 		break;
292 	case WLAN_CIPHER_SUITE_WEP104:
293 		if (params->key_len != WLAN_KEY_LEN_WEP104)
294 			return -EINVAL;
295 		break;
296 	case WLAN_CIPHER_SUITE_AES_CMAC:
297 		if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
298 			return -EINVAL;
299 		break;
300 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
301 		if (params->key_len != WLAN_KEY_LEN_BIP_CMAC_256)
302 			return -EINVAL;
303 		break;
304 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
305 		if (params->key_len != WLAN_KEY_LEN_BIP_GMAC_128)
306 			return -EINVAL;
307 		break;
308 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
309 		if (params->key_len != WLAN_KEY_LEN_BIP_GMAC_256)
310 			return -EINVAL;
311 		break;
312 	default:
313 		/*
314 		 * We don't know anything about this algorithm,
315 		 * allow using it -- but the driver must check
316 		 * all parameters! We still check below whether
317 		 * or not the driver supports this algorithm,
318 		 * of course.
319 		 */
320 		break;
321 	}
322 
323 	if (params->seq) {
324 		switch (params->cipher) {
325 		case WLAN_CIPHER_SUITE_WEP40:
326 		case WLAN_CIPHER_SUITE_WEP104:
327 			/* These ciphers do not use key sequence */
328 			return -EINVAL;
329 		case WLAN_CIPHER_SUITE_TKIP:
330 		case WLAN_CIPHER_SUITE_CCMP:
331 		case WLAN_CIPHER_SUITE_CCMP_256:
332 		case WLAN_CIPHER_SUITE_GCMP:
333 		case WLAN_CIPHER_SUITE_GCMP_256:
334 		case WLAN_CIPHER_SUITE_AES_CMAC:
335 		case WLAN_CIPHER_SUITE_BIP_CMAC_256:
336 		case WLAN_CIPHER_SUITE_BIP_GMAC_128:
337 		case WLAN_CIPHER_SUITE_BIP_GMAC_256:
338 			if (params->seq_len != 6)
339 				return -EINVAL;
340 			break;
341 		}
342 	}
343 
344 	if (!cfg80211_supported_cipher_suite(&rdev->wiphy, params->cipher))
345 		return -EINVAL;
346 
347 	return 0;
348 }
349 
350 unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
351 {
352 	unsigned int hdrlen = 24;
353 
354 	if (ieee80211_is_data(fc)) {
355 		if (ieee80211_has_a4(fc))
356 			hdrlen = 30;
357 		if (ieee80211_is_data_qos(fc)) {
358 			hdrlen += IEEE80211_QOS_CTL_LEN;
359 			if (ieee80211_has_order(fc))
360 				hdrlen += IEEE80211_HT_CTL_LEN;
361 		}
362 		goto out;
363 	}
364 
365 	if (ieee80211_is_mgmt(fc)) {
366 		if (ieee80211_has_order(fc))
367 			hdrlen += IEEE80211_HT_CTL_LEN;
368 		goto out;
369 	}
370 
371 	if (ieee80211_is_ctl(fc)) {
372 		/*
373 		 * ACK and CTS are 10 bytes, all others 16. To see how
374 		 * to get this condition consider
375 		 *   subtype mask:   0b0000000011110000 (0x00F0)
376 		 *   ACK subtype:    0b0000000011010000 (0x00D0)
377 		 *   CTS subtype:    0b0000000011000000 (0x00C0)
378 		 *   bits that matter:         ^^^      (0x00E0)
379 		 *   value of those: 0b0000000011000000 (0x00C0)
380 		 */
381 		if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
382 			hdrlen = 10;
383 		else
384 			hdrlen = 16;
385 	}
386 out:
387 	return hdrlen;
388 }
389 EXPORT_SYMBOL(ieee80211_hdrlen);
390 
391 unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
392 {
393 	const struct ieee80211_hdr *hdr =
394 			(const struct ieee80211_hdr *)skb->data;
395 	unsigned int hdrlen;
396 
397 	if (unlikely(skb->len < 10))
398 		return 0;
399 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
400 	if (unlikely(hdrlen > skb->len))
401 		return 0;
402 	return hdrlen;
403 }
404 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
405 
406 static unsigned int __ieee80211_get_mesh_hdrlen(u8 flags)
407 {
408 	int ae = flags & MESH_FLAGS_AE;
409 	/* 802.11-2012, 8.2.4.7.3 */
410 	switch (ae) {
411 	default:
412 	case 0:
413 		return 6;
414 	case MESH_FLAGS_AE_A4:
415 		return 12;
416 	case MESH_FLAGS_AE_A5_A6:
417 		return 18;
418 	}
419 }
420 
421 unsigned int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
422 {
423 	return __ieee80211_get_mesh_hdrlen(meshhdr->flags);
424 }
425 EXPORT_SYMBOL(ieee80211_get_mesh_hdrlen);
426 
427 int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr,
428 				  const u8 *addr, enum nl80211_iftype iftype,
429 				  u8 data_offset)
430 {
431 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
432 	struct {
433 		u8 hdr[ETH_ALEN] __aligned(2);
434 		__be16 proto;
435 	} payload;
436 	struct ethhdr tmp;
437 	u16 hdrlen;
438 	u8 mesh_flags = 0;
439 
440 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
441 		return -1;
442 
443 	hdrlen = ieee80211_hdrlen(hdr->frame_control) + data_offset;
444 	if (skb->len < hdrlen + 8)
445 		return -1;
446 
447 	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
448 	 * header
449 	 * IEEE 802.11 address fields:
450 	 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
451 	 *   0     0   DA    SA    BSSID n/a
452 	 *   0     1   DA    BSSID SA    n/a
453 	 *   1     0   BSSID SA    DA    n/a
454 	 *   1     1   RA    TA    DA    SA
455 	 */
456 	memcpy(tmp.h_dest, ieee80211_get_DA(hdr), ETH_ALEN);
457 	memcpy(tmp.h_source, ieee80211_get_SA(hdr), ETH_ALEN);
458 
459 	if (iftype == NL80211_IFTYPE_MESH_POINT)
460 		skb_copy_bits(skb, hdrlen, &mesh_flags, 1);
461 
462 	mesh_flags &= MESH_FLAGS_AE;
463 
464 	switch (hdr->frame_control &
465 		cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
466 	case cpu_to_le16(IEEE80211_FCTL_TODS):
467 		if (unlikely(iftype != NL80211_IFTYPE_AP &&
468 			     iftype != NL80211_IFTYPE_AP_VLAN &&
469 			     iftype != NL80211_IFTYPE_P2P_GO))
470 			return -1;
471 		break;
472 	case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
473 		if (unlikely(iftype != NL80211_IFTYPE_WDS &&
474 			     iftype != NL80211_IFTYPE_MESH_POINT &&
475 			     iftype != NL80211_IFTYPE_AP_VLAN &&
476 			     iftype != NL80211_IFTYPE_STATION))
477 			return -1;
478 		if (iftype == NL80211_IFTYPE_MESH_POINT) {
479 			if (mesh_flags == MESH_FLAGS_AE_A4)
480 				return -1;
481 			if (mesh_flags == MESH_FLAGS_AE_A5_A6) {
482 				skb_copy_bits(skb, hdrlen +
483 					offsetof(struct ieee80211s_hdr, eaddr1),
484 					tmp.h_dest, 2 * ETH_ALEN);
485 			}
486 			hdrlen += __ieee80211_get_mesh_hdrlen(mesh_flags);
487 		}
488 		break;
489 	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
490 		if ((iftype != NL80211_IFTYPE_STATION &&
491 		     iftype != NL80211_IFTYPE_P2P_CLIENT &&
492 		     iftype != NL80211_IFTYPE_MESH_POINT) ||
493 		    (is_multicast_ether_addr(tmp.h_dest) &&
494 		     ether_addr_equal(tmp.h_source, addr)))
495 			return -1;
496 		if (iftype == NL80211_IFTYPE_MESH_POINT) {
497 			if (mesh_flags == MESH_FLAGS_AE_A5_A6)
498 				return -1;
499 			if (mesh_flags == MESH_FLAGS_AE_A4)
500 				skb_copy_bits(skb, hdrlen +
501 					offsetof(struct ieee80211s_hdr, eaddr1),
502 					tmp.h_source, ETH_ALEN);
503 			hdrlen += __ieee80211_get_mesh_hdrlen(mesh_flags);
504 		}
505 		break;
506 	case cpu_to_le16(0):
507 		if (iftype != NL80211_IFTYPE_ADHOC &&
508 		    iftype != NL80211_IFTYPE_STATION &&
509 		    iftype != NL80211_IFTYPE_OCB)
510 				return -1;
511 		break;
512 	}
513 
514 	skb_copy_bits(skb, hdrlen, &payload, sizeof(payload));
515 	tmp.h_proto = payload.proto;
516 
517 	if (likely((ether_addr_equal(payload.hdr, rfc1042_header) &&
518 		    tmp.h_proto != htons(ETH_P_AARP) &&
519 		    tmp.h_proto != htons(ETH_P_IPX)) ||
520 		   ether_addr_equal(payload.hdr, bridge_tunnel_header)))
521 		/* remove RFC1042 or Bridge-Tunnel encapsulation and
522 		 * replace EtherType */
523 		hdrlen += ETH_ALEN + 2;
524 	else
525 		tmp.h_proto = htons(skb->len - hdrlen);
526 
527 	pskb_pull(skb, hdrlen);
528 
529 	if (!ehdr)
530 		ehdr = skb_push(skb, sizeof(struct ethhdr));
531 	memcpy(ehdr, &tmp, sizeof(tmp));
532 
533 	return 0;
534 }
535 EXPORT_SYMBOL(ieee80211_data_to_8023_exthdr);
536 
537 static void
538 __frame_add_frag(struct sk_buff *skb, struct page *page,
539 		 void *ptr, int len, int size)
540 {
541 	struct skb_shared_info *sh = skb_shinfo(skb);
542 	int page_offset;
543 
544 	page_ref_inc(page);
545 	page_offset = ptr - page_address(page);
546 	skb_add_rx_frag(skb, sh->nr_frags, page, page_offset, len, size);
547 }
548 
549 static void
550 __ieee80211_amsdu_copy_frag(struct sk_buff *skb, struct sk_buff *frame,
551 			    int offset, int len)
552 {
553 	struct skb_shared_info *sh = skb_shinfo(skb);
554 	const skb_frag_t *frag = &sh->frags[0];
555 	struct page *frag_page;
556 	void *frag_ptr;
557 	int frag_len, frag_size;
558 	int head_size = skb->len - skb->data_len;
559 	int cur_len;
560 
561 	frag_page = virt_to_head_page(skb->head);
562 	frag_ptr = skb->data;
563 	frag_size = head_size;
564 
565 	while (offset >= frag_size) {
566 		offset -= frag_size;
567 		frag_page = skb_frag_page(frag);
568 		frag_ptr = skb_frag_address(frag);
569 		frag_size = skb_frag_size(frag);
570 		frag++;
571 	}
572 
573 	frag_ptr += offset;
574 	frag_len = frag_size - offset;
575 
576 	cur_len = min(len, frag_len);
577 
578 	__frame_add_frag(frame, frag_page, frag_ptr, cur_len, frag_size);
579 	len -= cur_len;
580 
581 	while (len > 0) {
582 		frag_len = skb_frag_size(frag);
583 		cur_len = min(len, frag_len);
584 		__frame_add_frag(frame, skb_frag_page(frag),
585 				 skb_frag_address(frag), cur_len, frag_len);
586 		len -= cur_len;
587 		frag++;
588 	}
589 }
590 
591 static struct sk_buff *
592 __ieee80211_amsdu_copy(struct sk_buff *skb, unsigned int hlen,
593 		       int offset, int len, bool reuse_frag)
594 {
595 	struct sk_buff *frame;
596 	int cur_len = len;
597 
598 	if (skb->len - offset < len)
599 		return NULL;
600 
601 	/*
602 	 * When reusing framents, copy some data to the head to simplify
603 	 * ethernet header handling and speed up protocol header processing
604 	 * in the stack later.
605 	 */
606 	if (reuse_frag)
607 		cur_len = min_t(int, len, 32);
608 
609 	/*
610 	 * Allocate and reserve two bytes more for payload
611 	 * alignment since sizeof(struct ethhdr) is 14.
612 	 */
613 	frame = dev_alloc_skb(hlen + sizeof(struct ethhdr) + 2 + cur_len);
614 	if (!frame)
615 		return NULL;
616 
617 	skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
618 	skb_copy_bits(skb, offset, skb_put(frame, cur_len), cur_len);
619 
620 	len -= cur_len;
621 	if (!len)
622 		return frame;
623 
624 	offset += cur_len;
625 	__ieee80211_amsdu_copy_frag(skb, frame, offset, len);
626 
627 	return frame;
628 }
629 
630 void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
631 			      const u8 *addr, enum nl80211_iftype iftype,
632 			      const unsigned int extra_headroom,
633 			      const u8 *check_da, const u8 *check_sa)
634 {
635 	unsigned int hlen = ALIGN(extra_headroom, 4);
636 	struct sk_buff *frame = NULL;
637 	u16 ethertype;
638 	u8 *payload;
639 	int offset = 0, remaining;
640 	struct ethhdr eth;
641 	bool reuse_frag = skb->head_frag && !skb_has_frag_list(skb);
642 	bool reuse_skb = false;
643 	bool last = false;
644 
645 	while (!last) {
646 		unsigned int subframe_len;
647 		int len;
648 		u8 padding;
649 
650 		skb_copy_bits(skb, offset, &eth, sizeof(eth));
651 		len = ntohs(eth.h_proto);
652 		subframe_len = sizeof(struct ethhdr) + len;
653 		padding = (4 - subframe_len) & 0x3;
654 
655 		/* the last MSDU has no padding */
656 		remaining = skb->len - offset;
657 		if (subframe_len > remaining)
658 			goto purge;
659 
660 		offset += sizeof(struct ethhdr);
661 		last = remaining <= subframe_len + padding;
662 
663 		/* FIXME: should we really accept multicast DA? */
664 		if ((check_da && !is_multicast_ether_addr(eth.h_dest) &&
665 		     !ether_addr_equal(check_da, eth.h_dest)) ||
666 		    (check_sa && !ether_addr_equal(check_sa, eth.h_source))) {
667 			offset += len + padding;
668 			continue;
669 		}
670 
671 		/* reuse skb for the last subframe */
672 		if (!skb_is_nonlinear(skb) && !reuse_frag && last) {
673 			skb_pull(skb, offset);
674 			frame = skb;
675 			reuse_skb = true;
676 		} else {
677 			frame = __ieee80211_amsdu_copy(skb, hlen, offset, len,
678 						       reuse_frag);
679 			if (!frame)
680 				goto purge;
681 
682 			offset += len + padding;
683 		}
684 
685 		skb_reset_network_header(frame);
686 		frame->dev = skb->dev;
687 		frame->priority = skb->priority;
688 
689 		payload = frame->data;
690 		ethertype = (payload[6] << 8) | payload[7];
691 		if (likely((ether_addr_equal(payload, rfc1042_header) &&
692 			    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
693 			   ether_addr_equal(payload, bridge_tunnel_header))) {
694 			eth.h_proto = htons(ethertype);
695 			skb_pull(frame, ETH_ALEN + 2);
696 		}
697 
698 		memcpy(skb_push(frame, sizeof(eth)), &eth, sizeof(eth));
699 		__skb_queue_tail(list, frame);
700 	}
701 
702 	if (!reuse_skb)
703 		dev_kfree_skb(skb);
704 
705 	return;
706 
707  purge:
708 	__skb_queue_purge(list);
709 	dev_kfree_skb(skb);
710 }
711 EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
712 
713 /* Given a data frame determine the 802.1p/1d tag to use. */
714 unsigned int cfg80211_classify8021d(struct sk_buff *skb,
715 				    struct cfg80211_qos_map *qos_map)
716 {
717 	unsigned int dscp;
718 	unsigned char vlan_priority;
719 	unsigned int ret;
720 
721 	/* skb->priority values from 256->263 are magic values to
722 	 * directly indicate a specific 802.1d priority.  This is used
723 	 * to allow 802.1d priority to be passed directly in from VLAN
724 	 * tags, etc.
725 	 */
726 	if (skb->priority >= 256 && skb->priority <= 263) {
727 		ret = skb->priority - 256;
728 		goto out;
729 	}
730 
731 	if (skb_vlan_tag_present(skb)) {
732 		vlan_priority = (skb_vlan_tag_get(skb) & VLAN_PRIO_MASK)
733 			>> VLAN_PRIO_SHIFT;
734 		if (vlan_priority > 0) {
735 			ret = vlan_priority;
736 			goto out;
737 		}
738 	}
739 
740 	switch (skb->protocol) {
741 	case htons(ETH_P_IP):
742 		dscp = ipv4_get_dsfield(ip_hdr(skb)) & 0xfc;
743 		break;
744 	case htons(ETH_P_IPV6):
745 		dscp = ipv6_get_dsfield(ipv6_hdr(skb)) & 0xfc;
746 		break;
747 	case htons(ETH_P_MPLS_UC):
748 	case htons(ETH_P_MPLS_MC): {
749 		struct mpls_label mpls_tmp, *mpls;
750 
751 		mpls = skb_header_pointer(skb, sizeof(struct ethhdr),
752 					  sizeof(*mpls), &mpls_tmp);
753 		if (!mpls)
754 			return 0;
755 
756 		ret = (ntohl(mpls->entry) & MPLS_LS_TC_MASK)
757 			>> MPLS_LS_TC_SHIFT;
758 		goto out;
759 	}
760 	case htons(ETH_P_80221):
761 		/* 802.21 is always network control traffic */
762 		return 7;
763 	default:
764 		return 0;
765 	}
766 
767 	if (qos_map) {
768 		unsigned int i, tmp_dscp = dscp >> 2;
769 
770 		for (i = 0; i < qos_map->num_des; i++) {
771 			if (tmp_dscp == qos_map->dscp_exception[i].dscp) {
772 				ret = qos_map->dscp_exception[i].up;
773 				goto out;
774 			}
775 		}
776 
777 		for (i = 0; i < 8; i++) {
778 			if (tmp_dscp >= qos_map->up[i].low &&
779 			    tmp_dscp <= qos_map->up[i].high) {
780 				ret = i;
781 				goto out;
782 			}
783 		}
784 	}
785 
786 	ret = dscp >> 5;
787 out:
788 	return array_index_nospec(ret, IEEE80211_NUM_TIDS);
789 }
790 EXPORT_SYMBOL(cfg80211_classify8021d);
791 
792 const struct element *ieee80211_bss_get_elem(struct cfg80211_bss *bss, u8 id)
793 {
794 	const struct cfg80211_bss_ies *ies;
795 
796 	ies = rcu_dereference(bss->ies);
797 	if (!ies)
798 		return NULL;
799 
800 	return cfg80211_find_elem(id, ies->data, ies->len);
801 }
802 EXPORT_SYMBOL(ieee80211_bss_get_elem);
803 
804 void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
805 {
806 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
807 	struct net_device *dev = wdev->netdev;
808 	int i;
809 
810 	if (!wdev->connect_keys)
811 		return;
812 
813 	for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++) {
814 		if (!wdev->connect_keys->params[i].cipher)
815 			continue;
816 		if (rdev_add_key(rdev, dev, i, false, NULL,
817 				 &wdev->connect_keys->params[i])) {
818 			netdev_err(dev, "failed to set key %d\n", i);
819 			continue;
820 		}
821 		if (wdev->connect_keys->def == i &&
822 		    rdev_set_default_key(rdev, dev, i, true, true)) {
823 			netdev_err(dev, "failed to set defkey %d\n", i);
824 			continue;
825 		}
826 	}
827 
828 	kzfree(wdev->connect_keys);
829 	wdev->connect_keys = NULL;
830 }
831 
832 void cfg80211_process_wdev_events(struct wireless_dev *wdev)
833 {
834 	struct cfg80211_event *ev;
835 	unsigned long flags;
836 
837 	spin_lock_irqsave(&wdev->event_lock, flags);
838 	while (!list_empty(&wdev->event_list)) {
839 		ev = list_first_entry(&wdev->event_list,
840 				      struct cfg80211_event, list);
841 		list_del(&ev->list);
842 		spin_unlock_irqrestore(&wdev->event_lock, flags);
843 
844 		wdev_lock(wdev);
845 		switch (ev->type) {
846 		case EVENT_CONNECT_RESULT:
847 			__cfg80211_connect_result(
848 				wdev->netdev,
849 				&ev->cr,
850 				ev->cr.status == WLAN_STATUS_SUCCESS);
851 			break;
852 		case EVENT_ROAMED:
853 			__cfg80211_roamed(wdev, &ev->rm);
854 			break;
855 		case EVENT_DISCONNECTED:
856 			__cfg80211_disconnected(wdev->netdev,
857 						ev->dc.ie, ev->dc.ie_len,
858 						ev->dc.reason,
859 						!ev->dc.locally_generated);
860 			break;
861 		case EVENT_IBSS_JOINED:
862 			__cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid,
863 					       ev->ij.channel);
864 			break;
865 		case EVENT_STOPPED:
866 			__cfg80211_leave(wiphy_to_rdev(wdev->wiphy), wdev);
867 			break;
868 		case EVENT_PORT_AUTHORIZED:
869 			__cfg80211_port_authorized(wdev, ev->pa.bssid);
870 			break;
871 		}
872 		wdev_unlock(wdev);
873 
874 		kfree(ev);
875 
876 		spin_lock_irqsave(&wdev->event_lock, flags);
877 	}
878 	spin_unlock_irqrestore(&wdev->event_lock, flags);
879 }
880 
881 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
882 {
883 	struct wireless_dev *wdev;
884 
885 	ASSERT_RTNL();
886 
887 	list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list)
888 		cfg80211_process_wdev_events(wdev);
889 }
890 
891 int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
892 			  struct net_device *dev, enum nl80211_iftype ntype,
893 			  struct vif_params *params)
894 {
895 	int err;
896 	enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
897 
898 	ASSERT_RTNL();
899 
900 	/* don't support changing VLANs, you just re-create them */
901 	if (otype == NL80211_IFTYPE_AP_VLAN)
902 		return -EOPNOTSUPP;
903 
904 	/* cannot change into P2P device or NAN */
905 	if (ntype == NL80211_IFTYPE_P2P_DEVICE ||
906 	    ntype == NL80211_IFTYPE_NAN)
907 		return -EOPNOTSUPP;
908 
909 	if (!rdev->ops->change_virtual_intf ||
910 	    !(rdev->wiphy.interface_modes & (1 << ntype)))
911 		return -EOPNOTSUPP;
912 
913 	/* if it's part of a bridge, reject changing type to station/ibss */
914 	if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
915 	    (ntype == NL80211_IFTYPE_ADHOC ||
916 	     ntype == NL80211_IFTYPE_STATION ||
917 	     ntype == NL80211_IFTYPE_P2P_CLIENT))
918 		return -EBUSY;
919 
920 	if (ntype != otype) {
921 		dev->ieee80211_ptr->use_4addr = false;
922 		dev->ieee80211_ptr->mesh_id_up_len = 0;
923 		wdev_lock(dev->ieee80211_ptr);
924 		rdev_set_qos_map(rdev, dev, NULL);
925 		wdev_unlock(dev->ieee80211_ptr);
926 
927 		switch (otype) {
928 		case NL80211_IFTYPE_AP:
929 			cfg80211_stop_ap(rdev, dev, true);
930 			break;
931 		case NL80211_IFTYPE_ADHOC:
932 			cfg80211_leave_ibss(rdev, dev, false);
933 			break;
934 		case NL80211_IFTYPE_STATION:
935 		case NL80211_IFTYPE_P2P_CLIENT:
936 			wdev_lock(dev->ieee80211_ptr);
937 			cfg80211_disconnect(rdev, dev,
938 					    WLAN_REASON_DEAUTH_LEAVING, true);
939 			wdev_unlock(dev->ieee80211_ptr);
940 			break;
941 		case NL80211_IFTYPE_MESH_POINT:
942 			/* mesh should be handled? */
943 			break;
944 		default:
945 			break;
946 		}
947 
948 		cfg80211_process_rdev_events(rdev);
949 	}
950 
951 	err = rdev_change_virtual_intf(rdev, dev, ntype, params);
952 
953 	WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
954 
955 	if (!err && params && params->use_4addr != -1)
956 		dev->ieee80211_ptr->use_4addr = params->use_4addr;
957 
958 	if (!err) {
959 		dev->priv_flags &= ~IFF_DONT_BRIDGE;
960 		switch (ntype) {
961 		case NL80211_IFTYPE_STATION:
962 			if (dev->ieee80211_ptr->use_4addr)
963 				break;
964 			/* fall through */
965 		case NL80211_IFTYPE_OCB:
966 		case NL80211_IFTYPE_P2P_CLIENT:
967 		case NL80211_IFTYPE_ADHOC:
968 			dev->priv_flags |= IFF_DONT_BRIDGE;
969 			break;
970 		case NL80211_IFTYPE_P2P_GO:
971 		case NL80211_IFTYPE_AP:
972 		case NL80211_IFTYPE_AP_VLAN:
973 		case NL80211_IFTYPE_WDS:
974 		case NL80211_IFTYPE_MESH_POINT:
975 			/* bridging OK */
976 			break;
977 		case NL80211_IFTYPE_MONITOR:
978 			/* monitor can't bridge anyway */
979 			break;
980 		case NL80211_IFTYPE_UNSPECIFIED:
981 		case NUM_NL80211_IFTYPES:
982 			/* not happening */
983 			break;
984 		case NL80211_IFTYPE_P2P_DEVICE:
985 		case NL80211_IFTYPE_NAN:
986 			WARN_ON(1);
987 			break;
988 		}
989 	}
990 
991 	if (!err && ntype != otype && netif_running(dev)) {
992 		cfg80211_update_iface_num(rdev, ntype, 1);
993 		cfg80211_update_iface_num(rdev, otype, -1);
994 	}
995 
996 	return err;
997 }
998 
999 static u32 cfg80211_calculate_bitrate_ht(struct rate_info *rate)
1000 {
1001 	int modulation, streams, bitrate;
1002 
1003 	/* the formula below does only work for MCS values smaller than 32 */
1004 	if (WARN_ON_ONCE(rate->mcs >= 32))
1005 		return 0;
1006 
1007 	modulation = rate->mcs & 7;
1008 	streams = (rate->mcs >> 3) + 1;
1009 
1010 	bitrate = (rate->bw == RATE_INFO_BW_40) ? 13500000 : 6500000;
1011 
1012 	if (modulation < 4)
1013 		bitrate *= (modulation + 1);
1014 	else if (modulation == 4)
1015 		bitrate *= (modulation + 2);
1016 	else
1017 		bitrate *= (modulation + 3);
1018 
1019 	bitrate *= streams;
1020 
1021 	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
1022 		bitrate = (bitrate / 9) * 10;
1023 
1024 	/* do NOT round down here */
1025 	return (bitrate + 50000) / 100000;
1026 }
1027 
1028 static u32 cfg80211_calculate_bitrate_60g(struct rate_info *rate)
1029 {
1030 	static const u32 __mcs2bitrate[] = {
1031 		/* control PHY */
1032 		[0] =   275,
1033 		/* SC PHY */
1034 		[1] =  3850,
1035 		[2] =  7700,
1036 		[3] =  9625,
1037 		[4] = 11550,
1038 		[5] = 12512, /* 1251.25 mbps */
1039 		[6] = 15400,
1040 		[7] = 19250,
1041 		[8] = 23100,
1042 		[9] = 25025,
1043 		[10] = 30800,
1044 		[11] = 38500,
1045 		[12] = 46200,
1046 		/* OFDM PHY */
1047 		[13] =  6930,
1048 		[14] =  8662, /* 866.25 mbps */
1049 		[15] = 13860,
1050 		[16] = 17325,
1051 		[17] = 20790,
1052 		[18] = 27720,
1053 		[19] = 34650,
1054 		[20] = 41580,
1055 		[21] = 45045,
1056 		[22] = 51975,
1057 		[23] = 62370,
1058 		[24] = 67568, /* 6756.75 mbps */
1059 		/* LP-SC PHY */
1060 		[25] =  6260,
1061 		[26] =  8340,
1062 		[27] = 11120,
1063 		[28] = 12510,
1064 		[29] = 16680,
1065 		[30] = 22240,
1066 		[31] = 25030,
1067 	};
1068 
1069 	if (WARN_ON_ONCE(rate->mcs >= ARRAY_SIZE(__mcs2bitrate)))
1070 		return 0;
1071 
1072 	return __mcs2bitrate[rate->mcs];
1073 }
1074 
1075 static u32 cfg80211_calculate_bitrate_vht(struct rate_info *rate)
1076 {
1077 	static const u32 base[4][10] = {
1078 		{   6500000,
1079 		   13000000,
1080 		   19500000,
1081 		   26000000,
1082 		   39000000,
1083 		   52000000,
1084 		   58500000,
1085 		   65000000,
1086 		   78000000,
1087 		/* not in the spec, but some devices use this: */
1088 		   86500000,
1089 		},
1090 		{  13500000,
1091 		   27000000,
1092 		   40500000,
1093 		   54000000,
1094 		   81000000,
1095 		  108000000,
1096 		  121500000,
1097 		  135000000,
1098 		  162000000,
1099 		  180000000,
1100 		},
1101 		{  29300000,
1102 		   58500000,
1103 		   87800000,
1104 		  117000000,
1105 		  175500000,
1106 		  234000000,
1107 		  263300000,
1108 		  292500000,
1109 		  351000000,
1110 		  390000000,
1111 		},
1112 		{  58500000,
1113 		  117000000,
1114 		  175500000,
1115 		  234000000,
1116 		  351000000,
1117 		  468000000,
1118 		  526500000,
1119 		  585000000,
1120 		  702000000,
1121 		  780000000,
1122 		},
1123 	};
1124 	u32 bitrate;
1125 	int idx;
1126 
1127 	if (rate->mcs > 9)
1128 		goto warn;
1129 
1130 	switch (rate->bw) {
1131 	case RATE_INFO_BW_160:
1132 		idx = 3;
1133 		break;
1134 	case RATE_INFO_BW_80:
1135 		idx = 2;
1136 		break;
1137 	case RATE_INFO_BW_40:
1138 		idx = 1;
1139 		break;
1140 	case RATE_INFO_BW_5:
1141 	case RATE_INFO_BW_10:
1142 	default:
1143 		goto warn;
1144 	case RATE_INFO_BW_20:
1145 		idx = 0;
1146 	}
1147 
1148 	bitrate = base[idx][rate->mcs];
1149 	bitrate *= rate->nss;
1150 
1151 	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
1152 		bitrate = (bitrate / 9) * 10;
1153 
1154 	/* do NOT round down here */
1155 	return (bitrate + 50000) / 100000;
1156  warn:
1157 	WARN_ONCE(1, "invalid rate bw=%d, mcs=%d, nss=%d\n",
1158 		  rate->bw, rate->mcs, rate->nss);
1159 	return 0;
1160 }
1161 
1162 static u32 cfg80211_calculate_bitrate_he(struct rate_info *rate)
1163 {
1164 #define SCALE 2048
1165 	u16 mcs_divisors[12] = {
1166 		34133, /* 16.666666... */
1167 		17067, /*  8.333333... */
1168 		11378, /*  5.555555... */
1169 		 8533, /*  4.166666... */
1170 		 5689, /*  2.777777... */
1171 		 4267, /*  2.083333... */
1172 		 3923, /*  1.851851... */
1173 		 3413, /*  1.666666... */
1174 		 2844, /*  1.388888... */
1175 		 2560, /*  1.250000... */
1176 		 2276, /*  1.111111... */
1177 		 2048, /*  1.000000... */
1178 	};
1179 	u32 rates_160M[3] = { 960777777, 907400000, 816666666 };
1180 	u32 rates_969[3] =  { 480388888, 453700000, 408333333 };
1181 	u32 rates_484[3] =  { 229411111, 216666666, 195000000 };
1182 	u32 rates_242[3] =  { 114711111, 108333333,  97500000 };
1183 	u32 rates_106[3] =  {  40000000,  37777777,  34000000 };
1184 	u32 rates_52[3]  =  {  18820000,  17777777,  16000000 };
1185 	u32 rates_26[3]  =  {   9411111,   8888888,   8000000 };
1186 	u64 tmp;
1187 	u32 result;
1188 
1189 	if (WARN_ON_ONCE(rate->mcs > 11))
1190 		return 0;
1191 
1192 	if (WARN_ON_ONCE(rate->he_gi > NL80211_RATE_INFO_HE_GI_3_2))
1193 		return 0;
1194 	if (WARN_ON_ONCE(rate->he_ru_alloc >
1195 			 NL80211_RATE_INFO_HE_RU_ALLOC_2x996))
1196 		return 0;
1197 	if (WARN_ON_ONCE(rate->nss < 1 || rate->nss > 8))
1198 		return 0;
1199 
1200 	if (rate->bw == RATE_INFO_BW_160)
1201 		result = rates_160M[rate->he_gi];
1202 	else if (rate->bw == RATE_INFO_BW_80 ||
1203 		 (rate->bw == RATE_INFO_BW_HE_RU &&
1204 		  rate->he_ru_alloc == NL80211_RATE_INFO_HE_RU_ALLOC_996))
1205 		result = rates_969[rate->he_gi];
1206 	else if (rate->bw == RATE_INFO_BW_40 ||
1207 		 (rate->bw == RATE_INFO_BW_HE_RU &&
1208 		  rate->he_ru_alloc == NL80211_RATE_INFO_HE_RU_ALLOC_484))
1209 		result = rates_484[rate->he_gi];
1210 	else if (rate->bw == RATE_INFO_BW_20 ||
1211 		 (rate->bw == RATE_INFO_BW_HE_RU &&
1212 		  rate->he_ru_alloc == NL80211_RATE_INFO_HE_RU_ALLOC_242))
1213 		result = rates_242[rate->he_gi];
1214 	else if (rate->bw == RATE_INFO_BW_HE_RU &&
1215 		 rate->he_ru_alloc == NL80211_RATE_INFO_HE_RU_ALLOC_106)
1216 		result = rates_106[rate->he_gi];
1217 	else if (rate->bw == RATE_INFO_BW_HE_RU &&
1218 		 rate->he_ru_alloc == NL80211_RATE_INFO_HE_RU_ALLOC_52)
1219 		result = rates_52[rate->he_gi];
1220 	else if (rate->bw == RATE_INFO_BW_HE_RU &&
1221 		 rate->he_ru_alloc == NL80211_RATE_INFO_HE_RU_ALLOC_26)
1222 		result = rates_26[rate->he_gi];
1223 	else if (WARN(1, "invalid HE MCS: bw:%d, ru:%d\n",
1224 		      rate->bw, rate->he_ru_alloc))
1225 		return 0;
1226 
1227 	/* now scale to the appropriate MCS */
1228 	tmp = result;
1229 	tmp *= SCALE;
1230 	do_div(tmp, mcs_divisors[rate->mcs]);
1231 	result = tmp;
1232 
1233 	/* and take NSS, DCM into account */
1234 	result = (result * rate->nss) / 8;
1235 	if (rate->he_dcm)
1236 		result /= 2;
1237 
1238 	return result;
1239 }
1240 
1241 u32 cfg80211_calculate_bitrate(struct rate_info *rate)
1242 {
1243 	if (rate->flags & RATE_INFO_FLAGS_MCS)
1244 		return cfg80211_calculate_bitrate_ht(rate);
1245 	if (rate->flags & RATE_INFO_FLAGS_60G)
1246 		return cfg80211_calculate_bitrate_60g(rate);
1247 	if (rate->flags & RATE_INFO_FLAGS_VHT_MCS)
1248 		return cfg80211_calculate_bitrate_vht(rate);
1249 	if (rate->flags & RATE_INFO_FLAGS_HE_MCS)
1250 		return cfg80211_calculate_bitrate_he(rate);
1251 
1252 	return rate->legacy;
1253 }
1254 EXPORT_SYMBOL(cfg80211_calculate_bitrate);
1255 
1256 int cfg80211_get_p2p_attr(const u8 *ies, unsigned int len,
1257 			  enum ieee80211_p2p_attr_id attr,
1258 			  u8 *buf, unsigned int bufsize)
1259 {
1260 	u8 *out = buf;
1261 	u16 attr_remaining = 0;
1262 	bool desired_attr = false;
1263 	u16 desired_len = 0;
1264 
1265 	while (len > 0) {
1266 		unsigned int iedatalen;
1267 		unsigned int copy;
1268 		const u8 *iedata;
1269 
1270 		if (len < 2)
1271 			return -EILSEQ;
1272 		iedatalen = ies[1];
1273 		if (iedatalen + 2 > len)
1274 			return -EILSEQ;
1275 
1276 		if (ies[0] != WLAN_EID_VENDOR_SPECIFIC)
1277 			goto cont;
1278 
1279 		if (iedatalen < 4)
1280 			goto cont;
1281 
1282 		iedata = ies + 2;
1283 
1284 		/* check WFA OUI, P2P subtype */
1285 		if (iedata[0] != 0x50 || iedata[1] != 0x6f ||
1286 		    iedata[2] != 0x9a || iedata[3] != 0x09)
1287 			goto cont;
1288 
1289 		iedatalen -= 4;
1290 		iedata += 4;
1291 
1292 		/* check attribute continuation into this IE */
1293 		copy = min_t(unsigned int, attr_remaining, iedatalen);
1294 		if (copy && desired_attr) {
1295 			desired_len += copy;
1296 			if (out) {
1297 				memcpy(out, iedata, min(bufsize, copy));
1298 				out += min(bufsize, copy);
1299 				bufsize -= min(bufsize, copy);
1300 			}
1301 
1302 
1303 			if (copy == attr_remaining)
1304 				return desired_len;
1305 		}
1306 
1307 		attr_remaining -= copy;
1308 		if (attr_remaining)
1309 			goto cont;
1310 
1311 		iedatalen -= copy;
1312 		iedata += copy;
1313 
1314 		while (iedatalen > 0) {
1315 			u16 attr_len;
1316 
1317 			/* P2P attribute ID & size must fit */
1318 			if (iedatalen < 3)
1319 				return -EILSEQ;
1320 			desired_attr = iedata[0] == attr;
1321 			attr_len = get_unaligned_le16(iedata + 1);
1322 			iedatalen -= 3;
1323 			iedata += 3;
1324 
1325 			copy = min_t(unsigned int, attr_len, iedatalen);
1326 
1327 			if (desired_attr) {
1328 				desired_len += copy;
1329 				if (out) {
1330 					memcpy(out, iedata, min(bufsize, copy));
1331 					out += min(bufsize, copy);
1332 					bufsize -= min(bufsize, copy);
1333 				}
1334 
1335 				if (copy == attr_len)
1336 					return desired_len;
1337 			}
1338 
1339 			iedata += copy;
1340 			iedatalen -= copy;
1341 			attr_remaining = attr_len - copy;
1342 		}
1343 
1344  cont:
1345 		len -= ies[1] + 2;
1346 		ies += ies[1] + 2;
1347 	}
1348 
1349 	if (attr_remaining && desired_attr)
1350 		return -EILSEQ;
1351 
1352 	return -ENOENT;
1353 }
1354 EXPORT_SYMBOL(cfg80211_get_p2p_attr);
1355 
1356 static bool ieee80211_id_in_list(const u8 *ids, int n_ids, u8 id, bool id_ext)
1357 {
1358 	int i;
1359 
1360 	/* Make sure array values are legal */
1361 	if (WARN_ON(ids[n_ids - 1] == WLAN_EID_EXTENSION))
1362 		return false;
1363 
1364 	i = 0;
1365 	while (i < n_ids) {
1366 		if (ids[i] == WLAN_EID_EXTENSION) {
1367 			if (id_ext && (ids[i + 1] == id))
1368 				return true;
1369 
1370 			i += 2;
1371 			continue;
1372 		}
1373 
1374 		if (ids[i] == id && !id_ext)
1375 			return true;
1376 
1377 		i++;
1378 	}
1379 	return false;
1380 }
1381 
1382 static size_t skip_ie(const u8 *ies, size_t ielen, size_t pos)
1383 {
1384 	/* we assume a validly formed IEs buffer */
1385 	u8 len = ies[pos + 1];
1386 
1387 	pos += 2 + len;
1388 
1389 	/* the IE itself must have 255 bytes for fragments to follow */
1390 	if (len < 255)
1391 		return pos;
1392 
1393 	while (pos < ielen && ies[pos] == WLAN_EID_FRAGMENT) {
1394 		len = ies[pos + 1];
1395 		pos += 2 + len;
1396 	}
1397 
1398 	return pos;
1399 }
1400 
1401 size_t ieee80211_ie_split_ric(const u8 *ies, size_t ielen,
1402 			      const u8 *ids, int n_ids,
1403 			      const u8 *after_ric, int n_after_ric,
1404 			      size_t offset)
1405 {
1406 	size_t pos = offset;
1407 
1408 	while (pos < ielen) {
1409 		u8 ext = 0;
1410 
1411 		if (ies[pos] == WLAN_EID_EXTENSION)
1412 			ext = 2;
1413 		if ((pos + ext) >= ielen)
1414 			break;
1415 
1416 		if (!ieee80211_id_in_list(ids, n_ids, ies[pos + ext],
1417 					  ies[pos] == WLAN_EID_EXTENSION))
1418 			break;
1419 
1420 		if (ies[pos] == WLAN_EID_RIC_DATA && n_after_ric) {
1421 			pos = skip_ie(ies, ielen, pos);
1422 
1423 			while (pos < ielen) {
1424 				if (ies[pos] == WLAN_EID_EXTENSION)
1425 					ext = 2;
1426 				else
1427 					ext = 0;
1428 
1429 				if ((pos + ext) >= ielen)
1430 					break;
1431 
1432 				if (!ieee80211_id_in_list(after_ric,
1433 							  n_after_ric,
1434 							  ies[pos + ext],
1435 							  ext == 2))
1436 					pos = skip_ie(ies, ielen, pos);
1437 				else
1438 					break;
1439 			}
1440 		} else {
1441 			pos = skip_ie(ies, ielen, pos);
1442 		}
1443 	}
1444 
1445 	return pos;
1446 }
1447 EXPORT_SYMBOL(ieee80211_ie_split_ric);
1448 
1449 bool ieee80211_operating_class_to_band(u8 operating_class,
1450 				       enum nl80211_band *band)
1451 {
1452 	switch (operating_class) {
1453 	case 112:
1454 	case 115 ... 127:
1455 	case 128 ... 130:
1456 		*band = NL80211_BAND_5GHZ;
1457 		return true;
1458 	case 81:
1459 	case 82:
1460 	case 83:
1461 	case 84:
1462 		*band = NL80211_BAND_2GHZ;
1463 		return true;
1464 	case 180:
1465 		*band = NL80211_BAND_60GHZ;
1466 		return true;
1467 	}
1468 
1469 	return false;
1470 }
1471 EXPORT_SYMBOL(ieee80211_operating_class_to_band);
1472 
1473 bool ieee80211_chandef_to_operating_class(struct cfg80211_chan_def *chandef,
1474 					  u8 *op_class)
1475 {
1476 	u8 vht_opclass;
1477 	u32 freq = chandef->center_freq1;
1478 
1479 	if (freq >= 2412 && freq <= 2472) {
1480 		if (chandef->width > NL80211_CHAN_WIDTH_40)
1481 			return false;
1482 
1483 		/* 2.407 GHz, channels 1..13 */
1484 		if (chandef->width == NL80211_CHAN_WIDTH_40) {
1485 			if (freq > chandef->chan->center_freq)
1486 				*op_class = 83; /* HT40+ */
1487 			else
1488 				*op_class = 84; /* HT40- */
1489 		} else {
1490 			*op_class = 81;
1491 		}
1492 
1493 		return true;
1494 	}
1495 
1496 	if (freq == 2484) {
1497 		if (chandef->width > NL80211_CHAN_WIDTH_40)
1498 			return false;
1499 
1500 		*op_class = 82; /* channel 14 */
1501 		return true;
1502 	}
1503 
1504 	switch (chandef->width) {
1505 	case NL80211_CHAN_WIDTH_80:
1506 		vht_opclass = 128;
1507 		break;
1508 	case NL80211_CHAN_WIDTH_160:
1509 		vht_opclass = 129;
1510 		break;
1511 	case NL80211_CHAN_WIDTH_80P80:
1512 		vht_opclass = 130;
1513 		break;
1514 	case NL80211_CHAN_WIDTH_10:
1515 	case NL80211_CHAN_WIDTH_5:
1516 		return false; /* unsupported for now */
1517 	default:
1518 		vht_opclass = 0;
1519 		break;
1520 	}
1521 
1522 	/* 5 GHz, channels 36..48 */
1523 	if (freq >= 5180 && freq <= 5240) {
1524 		if (vht_opclass) {
1525 			*op_class = vht_opclass;
1526 		} else if (chandef->width == NL80211_CHAN_WIDTH_40) {
1527 			if (freq > chandef->chan->center_freq)
1528 				*op_class = 116;
1529 			else
1530 				*op_class = 117;
1531 		} else {
1532 			*op_class = 115;
1533 		}
1534 
1535 		return true;
1536 	}
1537 
1538 	/* 5 GHz, channels 52..64 */
1539 	if (freq >= 5260 && freq <= 5320) {
1540 		if (vht_opclass) {
1541 			*op_class = vht_opclass;
1542 		} else if (chandef->width == NL80211_CHAN_WIDTH_40) {
1543 			if (freq > chandef->chan->center_freq)
1544 				*op_class = 119;
1545 			else
1546 				*op_class = 120;
1547 		} else {
1548 			*op_class = 118;
1549 		}
1550 
1551 		return true;
1552 	}
1553 
1554 	/* 5 GHz, channels 100..144 */
1555 	if (freq >= 5500 && freq <= 5720) {
1556 		if (vht_opclass) {
1557 			*op_class = vht_opclass;
1558 		} else if (chandef->width == NL80211_CHAN_WIDTH_40) {
1559 			if (freq > chandef->chan->center_freq)
1560 				*op_class = 122;
1561 			else
1562 				*op_class = 123;
1563 		} else {
1564 			*op_class = 121;
1565 		}
1566 
1567 		return true;
1568 	}
1569 
1570 	/* 5 GHz, channels 149..169 */
1571 	if (freq >= 5745 && freq <= 5845) {
1572 		if (vht_opclass) {
1573 			*op_class = vht_opclass;
1574 		} else if (chandef->width == NL80211_CHAN_WIDTH_40) {
1575 			if (freq > chandef->chan->center_freq)
1576 				*op_class = 126;
1577 			else
1578 				*op_class = 127;
1579 		} else if (freq <= 5805) {
1580 			*op_class = 124;
1581 		} else {
1582 			*op_class = 125;
1583 		}
1584 
1585 		return true;
1586 	}
1587 
1588 	/* 56.16 GHz, channel 1..4 */
1589 	if (freq >= 56160 + 2160 * 1 && freq <= 56160 + 2160 * 6) {
1590 		if (chandef->width >= NL80211_CHAN_WIDTH_40)
1591 			return false;
1592 
1593 		*op_class = 180;
1594 		return true;
1595 	}
1596 
1597 	/* not supported yet */
1598 	return false;
1599 }
1600 EXPORT_SYMBOL(ieee80211_chandef_to_operating_class);
1601 
1602 static void cfg80211_calculate_bi_data(struct wiphy *wiphy, u32 new_beacon_int,
1603 				       u32 *beacon_int_gcd,
1604 				       bool *beacon_int_different)
1605 {
1606 	struct wireless_dev *wdev;
1607 
1608 	*beacon_int_gcd = 0;
1609 	*beacon_int_different = false;
1610 
1611 	list_for_each_entry(wdev, &wiphy->wdev_list, list) {
1612 		if (!wdev->beacon_interval)
1613 			continue;
1614 
1615 		if (!*beacon_int_gcd) {
1616 			*beacon_int_gcd = wdev->beacon_interval;
1617 			continue;
1618 		}
1619 
1620 		if (wdev->beacon_interval == *beacon_int_gcd)
1621 			continue;
1622 
1623 		*beacon_int_different = true;
1624 		*beacon_int_gcd = gcd(*beacon_int_gcd, wdev->beacon_interval);
1625 	}
1626 
1627 	if (new_beacon_int && *beacon_int_gcd != new_beacon_int) {
1628 		if (*beacon_int_gcd)
1629 			*beacon_int_different = true;
1630 		*beacon_int_gcd = gcd(*beacon_int_gcd, new_beacon_int);
1631 	}
1632 }
1633 
1634 int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
1635 				 enum nl80211_iftype iftype, u32 beacon_int)
1636 {
1637 	/*
1638 	 * This is just a basic pre-condition check; if interface combinations
1639 	 * are possible the driver must already be checking those with a call
1640 	 * to cfg80211_check_combinations(), in which case we'll validate more
1641 	 * through the cfg80211_calculate_bi_data() call and code in
1642 	 * cfg80211_iter_combinations().
1643 	 */
1644 
1645 	if (beacon_int < 10 || beacon_int > 10000)
1646 		return -EINVAL;
1647 
1648 	return 0;
1649 }
1650 
1651 int cfg80211_iter_combinations(struct wiphy *wiphy,
1652 			       struct iface_combination_params *params,
1653 			       void (*iter)(const struct ieee80211_iface_combination *c,
1654 					    void *data),
1655 			       void *data)
1656 {
1657 	const struct ieee80211_regdomain *regdom;
1658 	enum nl80211_dfs_regions region = 0;
1659 	int i, j, iftype;
1660 	int num_interfaces = 0;
1661 	u32 used_iftypes = 0;
1662 	u32 beacon_int_gcd;
1663 	bool beacon_int_different;
1664 
1665 	/*
1666 	 * This is a bit strange, since the iteration used to rely only on
1667 	 * the data given by the driver, but here it now relies on context,
1668 	 * in form of the currently operating interfaces.
1669 	 * This is OK for all current users, and saves us from having to
1670 	 * push the GCD calculations into all the drivers.
1671 	 * In the future, this should probably rely more on data that's in
1672 	 * cfg80211 already - the only thing not would appear to be any new
1673 	 * interfaces (while being brought up) and channel/radar data.
1674 	 */
1675 	cfg80211_calculate_bi_data(wiphy, params->new_beacon_int,
1676 				   &beacon_int_gcd, &beacon_int_different);
1677 
1678 	if (params->radar_detect) {
1679 		rcu_read_lock();
1680 		regdom = rcu_dereference(cfg80211_regdomain);
1681 		if (regdom)
1682 			region = regdom->dfs_region;
1683 		rcu_read_unlock();
1684 	}
1685 
1686 	for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
1687 		num_interfaces += params->iftype_num[iftype];
1688 		if (params->iftype_num[iftype] > 0 &&
1689 		    !(wiphy->software_iftypes & BIT(iftype)))
1690 			used_iftypes |= BIT(iftype);
1691 	}
1692 
1693 	for (i = 0; i < wiphy->n_iface_combinations; i++) {
1694 		const struct ieee80211_iface_combination *c;
1695 		struct ieee80211_iface_limit *limits;
1696 		u32 all_iftypes = 0;
1697 
1698 		c = &wiphy->iface_combinations[i];
1699 
1700 		if (num_interfaces > c->max_interfaces)
1701 			continue;
1702 		if (params->num_different_channels > c->num_different_channels)
1703 			continue;
1704 
1705 		limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
1706 				 GFP_KERNEL);
1707 		if (!limits)
1708 			return -ENOMEM;
1709 
1710 		for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
1711 			if (wiphy->software_iftypes & BIT(iftype))
1712 				continue;
1713 			for (j = 0; j < c->n_limits; j++) {
1714 				all_iftypes |= limits[j].types;
1715 				if (!(limits[j].types & BIT(iftype)))
1716 					continue;
1717 				if (limits[j].max < params->iftype_num[iftype])
1718 					goto cont;
1719 				limits[j].max -= params->iftype_num[iftype];
1720 			}
1721 		}
1722 
1723 		if (params->radar_detect !=
1724 			(c->radar_detect_widths & params->radar_detect))
1725 			goto cont;
1726 
1727 		if (params->radar_detect && c->radar_detect_regions &&
1728 		    !(c->radar_detect_regions & BIT(region)))
1729 			goto cont;
1730 
1731 		/* Finally check that all iftypes that we're currently
1732 		 * using are actually part of this combination. If they
1733 		 * aren't then we can't use this combination and have
1734 		 * to continue to the next.
1735 		 */
1736 		if ((all_iftypes & used_iftypes) != used_iftypes)
1737 			goto cont;
1738 
1739 		if (beacon_int_gcd) {
1740 			if (c->beacon_int_min_gcd &&
1741 			    beacon_int_gcd < c->beacon_int_min_gcd)
1742 				goto cont;
1743 			if (!c->beacon_int_min_gcd && beacon_int_different)
1744 				goto cont;
1745 		}
1746 
1747 		/* This combination covered all interface types and
1748 		 * supported the requested numbers, so we're good.
1749 		 */
1750 
1751 		(*iter)(c, data);
1752  cont:
1753 		kfree(limits);
1754 	}
1755 
1756 	return 0;
1757 }
1758 EXPORT_SYMBOL(cfg80211_iter_combinations);
1759 
1760 static void
1761 cfg80211_iter_sum_ifcombs(const struct ieee80211_iface_combination *c,
1762 			  void *data)
1763 {
1764 	int *num = data;
1765 	(*num)++;
1766 }
1767 
1768 int cfg80211_check_combinations(struct wiphy *wiphy,
1769 				struct iface_combination_params *params)
1770 {
1771 	int err, num = 0;
1772 
1773 	err = cfg80211_iter_combinations(wiphy, params,
1774 					 cfg80211_iter_sum_ifcombs, &num);
1775 	if (err)
1776 		return err;
1777 	if (num == 0)
1778 		return -EBUSY;
1779 
1780 	return 0;
1781 }
1782 EXPORT_SYMBOL(cfg80211_check_combinations);
1783 
1784 int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
1785 			   const u8 *rates, unsigned int n_rates,
1786 			   u32 *mask)
1787 {
1788 	int i, j;
1789 
1790 	if (!sband)
1791 		return -EINVAL;
1792 
1793 	if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
1794 		return -EINVAL;
1795 
1796 	*mask = 0;
1797 
1798 	for (i = 0; i < n_rates; i++) {
1799 		int rate = (rates[i] & 0x7f) * 5;
1800 		bool found = false;
1801 
1802 		for (j = 0; j < sband->n_bitrates; j++) {
1803 			if (sband->bitrates[j].bitrate == rate) {
1804 				found = true;
1805 				*mask |= BIT(j);
1806 				break;
1807 			}
1808 		}
1809 		if (!found)
1810 			return -EINVAL;
1811 	}
1812 
1813 	/*
1814 	 * mask must have at least one bit set here since we
1815 	 * didn't accept a 0-length rates array nor allowed
1816 	 * entries in the array that didn't exist
1817 	 */
1818 
1819 	return 0;
1820 }
1821 
1822 unsigned int ieee80211_get_num_supported_channels(struct wiphy *wiphy)
1823 {
1824 	enum nl80211_band band;
1825 	unsigned int n_channels = 0;
1826 
1827 	for (band = 0; band < NUM_NL80211_BANDS; band++)
1828 		if (wiphy->bands[band])
1829 			n_channels += wiphy->bands[band]->n_channels;
1830 
1831 	return n_channels;
1832 }
1833 EXPORT_SYMBOL(ieee80211_get_num_supported_channels);
1834 
1835 int cfg80211_get_station(struct net_device *dev, const u8 *mac_addr,
1836 			 struct station_info *sinfo)
1837 {
1838 	struct cfg80211_registered_device *rdev;
1839 	struct wireless_dev *wdev;
1840 
1841 	wdev = dev->ieee80211_ptr;
1842 	if (!wdev)
1843 		return -EOPNOTSUPP;
1844 
1845 	rdev = wiphy_to_rdev(wdev->wiphy);
1846 	if (!rdev->ops->get_station)
1847 		return -EOPNOTSUPP;
1848 
1849 	memset(sinfo, 0, sizeof(*sinfo));
1850 
1851 	return rdev_get_station(rdev, dev, mac_addr, sinfo);
1852 }
1853 EXPORT_SYMBOL(cfg80211_get_station);
1854 
1855 void cfg80211_free_nan_func(struct cfg80211_nan_func *f)
1856 {
1857 	int i;
1858 
1859 	if (!f)
1860 		return;
1861 
1862 	kfree(f->serv_spec_info);
1863 	kfree(f->srf_bf);
1864 	kfree(f->srf_macs);
1865 	for (i = 0; i < f->num_rx_filters; i++)
1866 		kfree(f->rx_filters[i].filter);
1867 
1868 	for (i = 0; i < f->num_tx_filters; i++)
1869 		kfree(f->tx_filters[i].filter);
1870 
1871 	kfree(f->rx_filters);
1872 	kfree(f->tx_filters);
1873 	kfree(f);
1874 }
1875 EXPORT_SYMBOL(cfg80211_free_nan_func);
1876 
1877 bool cfg80211_does_bw_fit_range(const struct ieee80211_freq_range *freq_range,
1878 				u32 center_freq_khz, u32 bw_khz)
1879 {
1880 	u32 start_freq_khz, end_freq_khz;
1881 
1882 	start_freq_khz = center_freq_khz - (bw_khz / 2);
1883 	end_freq_khz = center_freq_khz + (bw_khz / 2);
1884 
1885 	if (start_freq_khz >= freq_range->start_freq_khz &&
1886 	    end_freq_khz <= freq_range->end_freq_khz)
1887 		return true;
1888 
1889 	return false;
1890 }
1891 
1892 int cfg80211_sinfo_alloc_tid_stats(struct station_info *sinfo, gfp_t gfp)
1893 {
1894 	sinfo->pertid = kcalloc(IEEE80211_NUM_TIDS + 1,
1895 				sizeof(*(sinfo->pertid)),
1896 				gfp);
1897 	if (!sinfo->pertid)
1898 		return -ENOMEM;
1899 
1900 	return 0;
1901 }
1902 EXPORT_SYMBOL(cfg80211_sinfo_alloc_tid_stats);
1903 
1904 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
1905 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
1906 const unsigned char rfc1042_header[] __aligned(2) =
1907 	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
1908 EXPORT_SYMBOL(rfc1042_header);
1909 
1910 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
1911 const unsigned char bridge_tunnel_header[] __aligned(2) =
1912 	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
1913 EXPORT_SYMBOL(bridge_tunnel_header);
1914 
1915 /* Layer 2 Update frame (802.2 Type 1 LLC XID Update response) */
1916 struct iapp_layer2_update {
1917 	u8 da[ETH_ALEN];	/* broadcast */
1918 	u8 sa[ETH_ALEN];	/* STA addr */
1919 	__be16 len;		/* 6 */
1920 	u8 dsap;		/* 0 */
1921 	u8 ssap;		/* 0 */
1922 	u8 control;
1923 	u8 xid_info[3];
1924 } __packed;
1925 
1926 void cfg80211_send_layer2_update(struct net_device *dev, const u8 *addr)
1927 {
1928 	struct iapp_layer2_update *msg;
1929 	struct sk_buff *skb;
1930 
1931 	/* Send Level 2 Update Frame to update forwarding tables in layer 2
1932 	 * bridge devices */
1933 
1934 	skb = dev_alloc_skb(sizeof(*msg));
1935 	if (!skb)
1936 		return;
1937 	msg = skb_put(skb, sizeof(*msg));
1938 
1939 	/* 802.2 Type 1 Logical Link Control (LLC) Exchange Identifier (XID)
1940 	 * Update response frame; IEEE Std 802.2-1998, 5.4.1.2.1 */
1941 
1942 	eth_broadcast_addr(msg->da);
1943 	ether_addr_copy(msg->sa, addr);
1944 	msg->len = htons(6);
1945 	msg->dsap = 0;
1946 	msg->ssap = 0x01;	/* NULL LSAP, CR Bit: Response */
1947 	msg->control = 0xaf;	/* XID response lsb.1111F101.
1948 				 * F=0 (no poll command; unsolicited frame) */
1949 	msg->xid_info[0] = 0x81;	/* XID format identifier */
1950 	msg->xid_info[1] = 1;	/* LLC types/classes: Type 1 LLC */
1951 	msg->xid_info[2] = 0;	/* XID sender's receive window size (RW) */
1952 
1953 	skb->dev = dev;
1954 	skb->protocol = eth_type_trans(skb, dev);
1955 	memset(skb->cb, 0, sizeof(skb->cb));
1956 	netif_rx_ni(skb);
1957 }
1958 EXPORT_SYMBOL(cfg80211_send_layer2_update);
1959 
1960 int ieee80211_get_vht_max_nss(struct ieee80211_vht_cap *cap,
1961 			      enum ieee80211_vht_chanwidth bw,
1962 			      int mcs, bool ext_nss_bw_capable)
1963 {
1964 	u16 map = le16_to_cpu(cap->supp_mcs.rx_mcs_map);
1965 	int max_vht_nss = 0;
1966 	int ext_nss_bw;
1967 	int supp_width;
1968 	int i, mcs_encoding;
1969 
1970 	if (map == 0xffff)
1971 		return 0;
1972 
1973 	if (WARN_ON(mcs > 9))
1974 		return 0;
1975 	if (mcs <= 7)
1976 		mcs_encoding = 0;
1977 	else if (mcs == 8)
1978 		mcs_encoding = 1;
1979 	else
1980 		mcs_encoding = 2;
1981 
1982 	/* find max_vht_nss for the given MCS */
1983 	for (i = 7; i >= 0; i--) {
1984 		int supp = (map >> (2 * i)) & 3;
1985 
1986 		if (supp == 3)
1987 			continue;
1988 
1989 		if (supp >= mcs_encoding) {
1990 			max_vht_nss = i;
1991 			break;
1992 		}
1993 	}
1994 
1995 	if (!(cap->supp_mcs.tx_mcs_map &
1996 			cpu_to_le16(IEEE80211_VHT_EXT_NSS_BW_CAPABLE)))
1997 		return max_vht_nss;
1998 
1999 	ext_nss_bw = le32_get_bits(cap->vht_cap_info,
2000 				   IEEE80211_VHT_CAP_EXT_NSS_BW_MASK);
2001 	supp_width = le32_get_bits(cap->vht_cap_info,
2002 				   IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK);
2003 
2004 	/* if not capable, treat ext_nss_bw as 0 */
2005 	if (!ext_nss_bw_capable)
2006 		ext_nss_bw = 0;
2007 
2008 	/* This is invalid */
2009 	if (supp_width == 3)
2010 		return 0;
2011 
2012 	/* This is an invalid combination so pretend nothing is supported */
2013 	if (supp_width == 2 && (ext_nss_bw == 1 || ext_nss_bw == 2))
2014 		return 0;
2015 
2016 	/*
2017 	 * Cover all the special cases according to IEEE 802.11-2016
2018 	 * Table 9-250. All other cases are either factor of 1 or not
2019 	 * valid/supported.
2020 	 */
2021 	switch (bw) {
2022 	case IEEE80211_VHT_CHANWIDTH_USE_HT:
2023 	case IEEE80211_VHT_CHANWIDTH_80MHZ:
2024 		if ((supp_width == 1 || supp_width == 2) &&
2025 		    ext_nss_bw == 3)
2026 			return 2 * max_vht_nss;
2027 		break;
2028 	case IEEE80211_VHT_CHANWIDTH_160MHZ:
2029 		if (supp_width == 0 &&
2030 		    (ext_nss_bw == 1 || ext_nss_bw == 2))
2031 			return max_vht_nss / 2;
2032 		if (supp_width == 0 &&
2033 		    ext_nss_bw == 3)
2034 			return (3 * max_vht_nss) / 4;
2035 		if (supp_width == 1 &&
2036 		    ext_nss_bw == 3)
2037 			return 2 * max_vht_nss;
2038 		break;
2039 	case IEEE80211_VHT_CHANWIDTH_80P80MHZ:
2040 		if (supp_width == 0 && ext_nss_bw == 1)
2041 			return 0; /* not possible */
2042 		if (supp_width == 0 &&
2043 		    ext_nss_bw == 2)
2044 			return max_vht_nss / 2;
2045 		if (supp_width == 0 &&
2046 		    ext_nss_bw == 3)
2047 			return (3 * max_vht_nss) / 4;
2048 		if (supp_width == 1 &&
2049 		    ext_nss_bw == 0)
2050 			return 0; /* not possible */
2051 		if (supp_width == 1 &&
2052 		    ext_nss_bw == 1)
2053 			return max_vht_nss / 2;
2054 		if (supp_width == 1 &&
2055 		    ext_nss_bw == 2)
2056 			return (3 * max_vht_nss) / 4;
2057 		break;
2058 	}
2059 
2060 	/* not covered or invalid combination received */
2061 	return max_vht_nss;
2062 }
2063 EXPORT_SYMBOL(ieee80211_get_vht_max_nss);
2064