xref: /openbmc/linux/net/wireless/util.c (revision 05bcf503)
1 /*
2  * Wireless utility functions
3  *
4  * Copyright 2007-2009	Johannes Berg <johannes@sipsolutions.net>
5  */
6 #include <linux/export.h>
7 #include <linux/bitops.h>
8 #include <linux/etherdevice.h>
9 #include <linux/slab.h>
10 #include <net/cfg80211.h>
11 #include <net/ip.h>
12 #include <net/dsfield.h>
13 #include "core.h"
14 
15 struct ieee80211_rate *
16 ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
17 			    u32 basic_rates, int bitrate)
18 {
19 	struct ieee80211_rate *result = &sband->bitrates[0];
20 	int i;
21 
22 	for (i = 0; i < sband->n_bitrates; i++) {
23 		if (!(basic_rates & BIT(i)))
24 			continue;
25 		if (sband->bitrates[i].bitrate > bitrate)
26 			continue;
27 		result = &sband->bitrates[i];
28 	}
29 
30 	return result;
31 }
32 EXPORT_SYMBOL(ieee80211_get_response_rate);
33 
34 int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
35 {
36 	/* see 802.11 17.3.8.3.2 and Annex J
37 	 * there are overlapping channel numbers in 5GHz and 2GHz bands */
38 	if (chan <= 0)
39 		return 0; /* not supported */
40 	switch (band) {
41 	case IEEE80211_BAND_2GHZ:
42 		if (chan == 14)
43 			return 2484;
44 		else if (chan < 14)
45 			return 2407 + chan * 5;
46 		break;
47 	case IEEE80211_BAND_5GHZ:
48 		if (chan >= 182 && chan <= 196)
49 			return 4000 + chan * 5;
50 		else
51 			return 5000 + chan * 5;
52 		break;
53 	case IEEE80211_BAND_60GHZ:
54 		if (chan < 5)
55 			return 56160 + chan * 2160;
56 		break;
57 	default:
58 		;
59 	}
60 	return 0; /* not supported */
61 }
62 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
63 
64 int ieee80211_frequency_to_channel(int freq)
65 {
66 	/* see 802.11 17.3.8.3.2 and Annex J */
67 	if (freq == 2484)
68 		return 14;
69 	else if (freq < 2484)
70 		return (freq - 2407) / 5;
71 	else if (freq >= 4910 && freq <= 4980)
72 		return (freq - 4000) / 5;
73 	else if (freq <= 45000) /* DMG band lower limit */
74 		return (freq - 5000) / 5;
75 	else if (freq >= 58320 && freq <= 64800)
76 		return (freq - 56160) / 2160;
77 	else
78 		return 0;
79 }
80 EXPORT_SYMBOL(ieee80211_frequency_to_channel);
81 
82 struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
83 						  int freq)
84 {
85 	enum ieee80211_band band;
86 	struct ieee80211_supported_band *sband;
87 	int i;
88 
89 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
90 		sband = wiphy->bands[band];
91 
92 		if (!sband)
93 			continue;
94 
95 		for (i = 0; i < sband->n_channels; i++) {
96 			if (sband->channels[i].center_freq == freq)
97 				return &sband->channels[i];
98 		}
99 	}
100 
101 	return NULL;
102 }
103 EXPORT_SYMBOL(__ieee80211_get_channel);
104 
105 static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
106 				     enum ieee80211_band band)
107 {
108 	int i, want;
109 
110 	switch (band) {
111 	case IEEE80211_BAND_5GHZ:
112 		want = 3;
113 		for (i = 0; i < sband->n_bitrates; i++) {
114 			if (sband->bitrates[i].bitrate == 60 ||
115 			    sband->bitrates[i].bitrate == 120 ||
116 			    sband->bitrates[i].bitrate == 240) {
117 				sband->bitrates[i].flags |=
118 					IEEE80211_RATE_MANDATORY_A;
119 				want--;
120 			}
121 		}
122 		WARN_ON(want);
123 		break;
124 	case IEEE80211_BAND_2GHZ:
125 		want = 7;
126 		for (i = 0; i < sband->n_bitrates; i++) {
127 			if (sband->bitrates[i].bitrate == 10) {
128 				sband->bitrates[i].flags |=
129 					IEEE80211_RATE_MANDATORY_B |
130 					IEEE80211_RATE_MANDATORY_G;
131 				want--;
132 			}
133 
134 			if (sband->bitrates[i].bitrate == 20 ||
135 			    sband->bitrates[i].bitrate == 55 ||
136 			    sband->bitrates[i].bitrate == 110 ||
137 			    sband->bitrates[i].bitrate == 60 ||
138 			    sband->bitrates[i].bitrate == 120 ||
139 			    sband->bitrates[i].bitrate == 240) {
140 				sband->bitrates[i].flags |=
141 					IEEE80211_RATE_MANDATORY_G;
142 				want--;
143 			}
144 
145 			if (sband->bitrates[i].bitrate != 10 &&
146 			    sband->bitrates[i].bitrate != 20 &&
147 			    sband->bitrates[i].bitrate != 55 &&
148 			    sband->bitrates[i].bitrate != 110)
149 				sband->bitrates[i].flags |=
150 					IEEE80211_RATE_ERP_G;
151 		}
152 		WARN_ON(want != 0 && want != 3 && want != 6);
153 		break;
154 	case IEEE80211_BAND_60GHZ:
155 		/* check for mandatory HT MCS 1..4 */
156 		WARN_ON(!sband->ht_cap.ht_supported);
157 		WARN_ON((sband->ht_cap.mcs.rx_mask[0] & 0x1e) != 0x1e);
158 		break;
159 	case IEEE80211_NUM_BANDS:
160 		WARN_ON(1);
161 		break;
162 	}
163 }
164 
165 void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
166 {
167 	enum ieee80211_band band;
168 
169 	for (band = 0; band < IEEE80211_NUM_BANDS; band++)
170 		if (wiphy->bands[band])
171 			set_mandatory_flags_band(wiphy->bands[band], band);
172 }
173 
174 bool cfg80211_supported_cipher_suite(struct wiphy *wiphy, u32 cipher)
175 {
176 	int i;
177 	for (i = 0; i < wiphy->n_cipher_suites; i++)
178 		if (cipher == wiphy->cipher_suites[i])
179 			return true;
180 	return false;
181 }
182 
183 int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
184 				   struct key_params *params, int key_idx,
185 				   bool pairwise, const u8 *mac_addr)
186 {
187 	if (key_idx > 5)
188 		return -EINVAL;
189 
190 	if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
191 		return -EINVAL;
192 
193 	if (pairwise && !mac_addr)
194 		return -EINVAL;
195 
196 	/*
197 	 * Disallow pairwise keys with non-zero index unless it's WEP
198 	 * or a vendor specific cipher (because current deployments use
199 	 * pairwise WEP keys with non-zero indices and for vendor specific
200 	 * ciphers this should be validated in the driver or hardware level
201 	 * - but 802.11i clearly specifies to use zero)
202 	 */
203 	if (pairwise && key_idx &&
204 	    ((params->cipher == WLAN_CIPHER_SUITE_TKIP) ||
205 	     (params->cipher == WLAN_CIPHER_SUITE_CCMP) ||
206 	     (params->cipher == WLAN_CIPHER_SUITE_AES_CMAC)))
207 		return -EINVAL;
208 
209 	switch (params->cipher) {
210 	case WLAN_CIPHER_SUITE_WEP40:
211 		if (params->key_len != WLAN_KEY_LEN_WEP40)
212 			return -EINVAL;
213 		break;
214 	case WLAN_CIPHER_SUITE_TKIP:
215 		if (params->key_len != WLAN_KEY_LEN_TKIP)
216 			return -EINVAL;
217 		break;
218 	case WLAN_CIPHER_SUITE_CCMP:
219 		if (params->key_len != WLAN_KEY_LEN_CCMP)
220 			return -EINVAL;
221 		break;
222 	case WLAN_CIPHER_SUITE_WEP104:
223 		if (params->key_len != WLAN_KEY_LEN_WEP104)
224 			return -EINVAL;
225 		break;
226 	case WLAN_CIPHER_SUITE_AES_CMAC:
227 		if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
228 			return -EINVAL;
229 		break;
230 	default:
231 		/*
232 		 * We don't know anything about this algorithm,
233 		 * allow using it -- but the driver must check
234 		 * all parameters! We still check below whether
235 		 * or not the driver supports this algorithm,
236 		 * of course.
237 		 */
238 		break;
239 	}
240 
241 	if (params->seq) {
242 		switch (params->cipher) {
243 		case WLAN_CIPHER_SUITE_WEP40:
244 		case WLAN_CIPHER_SUITE_WEP104:
245 			/* These ciphers do not use key sequence */
246 			return -EINVAL;
247 		case WLAN_CIPHER_SUITE_TKIP:
248 		case WLAN_CIPHER_SUITE_CCMP:
249 		case WLAN_CIPHER_SUITE_AES_CMAC:
250 			if (params->seq_len != 6)
251 				return -EINVAL;
252 			break;
253 		}
254 	}
255 
256 	if (!cfg80211_supported_cipher_suite(&rdev->wiphy, params->cipher))
257 		return -EINVAL;
258 
259 	return 0;
260 }
261 
262 unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
263 {
264 	unsigned int hdrlen = 24;
265 
266 	if (ieee80211_is_data(fc)) {
267 		if (ieee80211_has_a4(fc))
268 			hdrlen = 30;
269 		if (ieee80211_is_data_qos(fc)) {
270 			hdrlen += IEEE80211_QOS_CTL_LEN;
271 			if (ieee80211_has_order(fc))
272 				hdrlen += IEEE80211_HT_CTL_LEN;
273 		}
274 		goto out;
275 	}
276 
277 	if (ieee80211_is_ctl(fc)) {
278 		/*
279 		 * ACK and CTS are 10 bytes, all others 16. To see how
280 		 * to get this condition consider
281 		 *   subtype mask:   0b0000000011110000 (0x00F0)
282 		 *   ACK subtype:    0b0000000011010000 (0x00D0)
283 		 *   CTS subtype:    0b0000000011000000 (0x00C0)
284 		 *   bits that matter:         ^^^      (0x00E0)
285 		 *   value of those: 0b0000000011000000 (0x00C0)
286 		 */
287 		if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
288 			hdrlen = 10;
289 		else
290 			hdrlen = 16;
291 	}
292 out:
293 	return hdrlen;
294 }
295 EXPORT_SYMBOL(ieee80211_hdrlen);
296 
297 unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
298 {
299 	const struct ieee80211_hdr *hdr =
300 			(const struct ieee80211_hdr *)skb->data;
301 	unsigned int hdrlen;
302 
303 	if (unlikely(skb->len < 10))
304 		return 0;
305 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
306 	if (unlikely(hdrlen > skb->len))
307 		return 0;
308 	return hdrlen;
309 }
310 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
311 
312 unsigned int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
313 {
314 	int ae = meshhdr->flags & MESH_FLAGS_AE;
315 	/* 802.11-2012, 8.2.4.7.3 */
316 	switch (ae) {
317 	default:
318 	case 0:
319 		return 6;
320 	case MESH_FLAGS_AE_A4:
321 		return 12;
322 	case MESH_FLAGS_AE_A5_A6:
323 		return 18;
324 	}
325 }
326 EXPORT_SYMBOL(ieee80211_get_mesh_hdrlen);
327 
328 int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
329 			   enum nl80211_iftype iftype)
330 {
331 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
332 	u16 hdrlen, ethertype;
333 	u8 *payload;
334 	u8 dst[ETH_ALEN];
335 	u8 src[ETH_ALEN] __aligned(2);
336 
337 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
338 		return -1;
339 
340 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
341 
342 	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
343 	 * header
344 	 * IEEE 802.11 address fields:
345 	 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
346 	 *   0     0   DA    SA    BSSID n/a
347 	 *   0     1   DA    BSSID SA    n/a
348 	 *   1     0   BSSID SA    DA    n/a
349 	 *   1     1   RA    TA    DA    SA
350 	 */
351 	memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
352 	memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
353 
354 	switch (hdr->frame_control &
355 		cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
356 	case cpu_to_le16(IEEE80211_FCTL_TODS):
357 		if (unlikely(iftype != NL80211_IFTYPE_AP &&
358 			     iftype != NL80211_IFTYPE_AP_VLAN &&
359 			     iftype != NL80211_IFTYPE_P2P_GO))
360 			return -1;
361 		break;
362 	case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
363 		if (unlikely(iftype != NL80211_IFTYPE_WDS &&
364 			     iftype != NL80211_IFTYPE_MESH_POINT &&
365 			     iftype != NL80211_IFTYPE_AP_VLAN &&
366 			     iftype != NL80211_IFTYPE_STATION))
367 			return -1;
368 		if (iftype == NL80211_IFTYPE_MESH_POINT) {
369 			struct ieee80211s_hdr *meshdr =
370 				(struct ieee80211s_hdr *) (skb->data + hdrlen);
371 			/* make sure meshdr->flags is on the linear part */
372 			if (!pskb_may_pull(skb, hdrlen + 1))
373 				return -1;
374 			if (meshdr->flags & MESH_FLAGS_AE_A4)
375 				return -1;
376 			if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
377 				skb_copy_bits(skb, hdrlen +
378 					offsetof(struct ieee80211s_hdr, eaddr1),
379 				       	dst, ETH_ALEN);
380 				skb_copy_bits(skb, hdrlen +
381 					offsetof(struct ieee80211s_hdr, eaddr2),
382 				        src, ETH_ALEN);
383 			}
384 			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
385 		}
386 		break;
387 	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
388 		if ((iftype != NL80211_IFTYPE_STATION &&
389 		     iftype != NL80211_IFTYPE_P2P_CLIENT &&
390 		     iftype != NL80211_IFTYPE_MESH_POINT) ||
391 		    (is_multicast_ether_addr(dst) &&
392 		     ether_addr_equal(src, addr)))
393 			return -1;
394 		if (iftype == NL80211_IFTYPE_MESH_POINT) {
395 			struct ieee80211s_hdr *meshdr =
396 				(struct ieee80211s_hdr *) (skb->data + hdrlen);
397 			/* make sure meshdr->flags is on the linear part */
398 			if (!pskb_may_pull(skb, hdrlen + 1))
399 				return -1;
400 			if (meshdr->flags & MESH_FLAGS_AE_A5_A6)
401 				return -1;
402 			if (meshdr->flags & MESH_FLAGS_AE_A4)
403 				skb_copy_bits(skb, hdrlen +
404 					offsetof(struct ieee80211s_hdr, eaddr1),
405 					src, ETH_ALEN);
406 			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
407 		}
408 		break;
409 	case cpu_to_le16(0):
410 		if (iftype != NL80211_IFTYPE_ADHOC &&
411 		    iftype != NL80211_IFTYPE_STATION)
412 				return -1;
413 		break;
414 	}
415 
416 	if (!pskb_may_pull(skb, hdrlen + 8))
417 		return -1;
418 
419 	payload = skb->data + hdrlen;
420 	ethertype = (payload[6] << 8) | payload[7];
421 
422 	if (likely((ether_addr_equal(payload, rfc1042_header) &&
423 		    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
424 		   ether_addr_equal(payload, bridge_tunnel_header))) {
425 		/* remove RFC1042 or Bridge-Tunnel encapsulation and
426 		 * replace EtherType */
427 		skb_pull(skb, hdrlen + 6);
428 		memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
429 		memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
430 	} else {
431 		struct ethhdr *ehdr;
432 		__be16 len;
433 
434 		skb_pull(skb, hdrlen);
435 		len = htons(skb->len);
436 		ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
437 		memcpy(ehdr->h_dest, dst, ETH_ALEN);
438 		memcpy(ehdr->h_source, src, ETH_ALEN);
439 		ehdr->h_proto = len;
440 	}
441 	return 0;
442 }
443 EXPORT_SYMBOL(ieee80211_data_to_8023);
444 
445 int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
446 			     enum nl80211_iftype iftype, u8 *bssid, bool qos)
447 {
448 	struct ieee80211_hdr hdr;
449 	u16 hdrlen, ethertype;
450 	__le16 fc;
451 	const u8 *encaps_data;
452 	int encaps_len, skip_header_bytes;
453 	int nh_pos, h_pos;
454 	int head_need;
455 
456 	if (unlikely(skb->len < ETH_HLEN))
457 		return -EINVAL;
458 
459 	nh_pos = skb_network_header(skb) - skb->data;
460 	h_pos = skb_transport_header(skb) - skb->data;
461 
462 	/* convert Ethernet header to proper 802.11 header (based on
463 	 * operation mode) */
464 	ethertype = (skb->data[12] << 8) | skb->data[13];
465 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
466 
467 	switch (iftype) {
468 	case NL80211_IFTYPE_AP:
469 	case NL80211_IFTYPE_AP_VLAN:
470 	case NL80211_IFTYPE_P2P_GO:
471 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
472 		/* DA BSSID SA */
473 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
474 		memcpy(hdr.addr2, addr, ETH_ALEN);
475 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
476 		hdrlen = 24;
477 		break;
478 	case NL80211_IFTYPE_STATION:
479 	case NL80211_IFTYPE_P2P_CLIENT:
480 		fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
481 		/* BSSID SA DA */
482 		memcpy(hdr.addr1, bssid, ETH_ALEN);
483 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
484 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
485 		hdrlen = 24;
486 		break;
487 	case NL80211_IFTYPE_ADHOC:
488 		/* DA SA BSSID */
489 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
490 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
491 		memcpy(hdr.addr3, bssid, ETH_ALEN);
492 		hdrlen = 24;
493 		break;
494 	default:
495 		return -EOPNOTSUPP;
496 	}
497 
498 	if (qos) {
499 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
500 		hdrlen += 2;
501 	}
502 
503 	hdr.frame_control = fc;
504 	hdr.duration_id = 0;
505 	hdr.seq_ctrl = 0;
506 
507 	skip_header_bytes = ETH_HLEN;
508 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
509 		encaps_data = bridge_tunnel_header;
510 		encaps_len = sizeof(bridge_tunnel_header);
511 		skip_header_bytes -= 2;
512 	} else if (ethertype > 0x600) {
513 		encaps_data = rfc1042_header;
514 		encaps_len = sizeof(rfc1042_header);
515 		skip_header_bytes -= 2;
516 	} else {
517 		encaps_data = NULL;
518 		encaps_len = 0;
519 	}
520 
521 	skb_pull(skb, skip_header_bytes);
522 	nh_pos -= skip_header_bytes;
523 	h_pos -= skip_header_bytes;
524 
525 	head_need = hdrlen + encaps_len - skb_headroom(skb);
526 
527 	if (head_need > 0 || skb_cloned(skb)) {
528 		head_need = max(head_need, 0);
529 		if (head_need)
530 			skb_orphan(skb);
531 
532 		if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC))
533 			return -ENOMEM;
534 
535 		skb->truesize += head_need;
536 	}
537 
538 	if (encaps_data) {
539 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
540 		nh_pos += encaps_len;
541 		h_pos += encaps_len;
542 	}
543 
544 	memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
545 
546 	nh_pos += hdrlen;
547 	h_pos += hdrlen;
548 
549 	/* Update skb pointers to various headers since this modified frame
550 	 * is going to go through Linux networking code that may potentially
551 	 * need things like pointer to IP header. */
552 	skb_set_mac_header(skb, 0);
553 	skb_set_network_header(skb, nh_pos);
554 	skb_set_transport_header(skb, h_pos);
555 
556 	return 0;
557 }
558 EXPORT_SYMBOL(ieee80211_data_from_8023);
559 
560 
561 void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
562 			      const u8 *addr, enum nl80211_iftype iftype,
563 			      const unsigned int extra_headroom,
564 			      bool has_80211_header)
565 {
566 	struct sk_buff *frame = NULL;
567 	u16 ethertype;
568 	u8 *payload;
569 	const struct ethhdr *eth;
570 	int remaining, err;
571 	u8 dst[ETH_ALEN], src[ETH_ALEN];
572 
573 	if (has_80211_header) {
574 		err = ieee80211_data_to_8023(skb, addr, iftype);
575 		if (err)
576 			goto out;
577 
578 		/* skip the wrapping header */
579 		eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
580 		if (!eth)
581 			goto out;
582 	} else {
583 		eth = (struct ethhdr *) skb->data;
584 	}
585 
586 	while (skb != frame) {
587 		u8 padding;
588 		__be16 len = eth->h_proto;
589 		unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
590 
591 		remaining = skb->len;
592 		memcpy(dst, eth->h_dest, ETH_ALEN);
593 		memcpy(src, eth->h_source, ETH_ALEN);
594 
595 		padding = (4 - subframe_len) & 0x3;
596 		/* the last MSDU has no padding */
597 		if (subframe_len > remaining)
598 			goto purge;
599 
600 		skb_pull(skb, sizeof(struct ethhdr));
601 		/* reuse skb for the last subframe */
602 		if (remaining <= subframe_len + padding)
603 			frame = skb;
604 		else {
605 			unsigned int hlen = ALIGN(extra_headroom, 4);
606 			/*
607 			 * Allocate and reserve two bytes more for payload
608 			 * alignment since sizeof(struct ethhdr) is 14.
609 			 */
610 			frame = dev_alloc_skb(hlen + subframe_len + 2);
611 			if (!frame)
612 				goto purge;
613 
614 			skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
615 			memcpy(skb_put(frame, ntohs(len)), skb->data,
616 				ntohs(len));
617 
618 			eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
619 							padding);
620 			if (!eth) {
621 				dev_kfree_skb(frame);
622 				goto purge;
623 			}
624 		}
625 
626 		skb_reset_network_header(frame);
627 		frame->dev = skb->dev;
628 		frame->priority = skb->priority;
629 
630 		payload = frame->data;
631 		ethertype = (payload[6] << 8) | payload[7];
632 
633 		if (likely((ether_addr_equal(payload, rfc1042_header) &&
634 			    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
635 			   ether_addr_equal(payload, bridge_tunnel_header))) {
636 			/* remove RFC1042 or Bridge-Tunnel
637 			 * encapsulation and replace EtherType */
638 			skb_pull(frame, 6);
639 			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
640 			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
641 		} else {
642 			memcpy(skb_push(frame, sizeof(__be16)), &len,
643 				sizeof(__be16));
644 			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
645 			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
646 		}
647 		__skb_queue_tail(list, frame);
648 	}
649 
650 	return;
651 
652  purge:
653 	__skb_queue_purge(list);
654  out:
655 	dev_kfree_skb(skb);
656 }
657 EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
658 
659 /* Given a data frame determine the 802.1p/1d tag to use. */
660 unsigned int cfg80211_classify8021d(struct sk_buff *skb)
661 {
662 	unsigned int dscp;
663 
664 	/* skb->priority values from 256->263 are magic values to
665 	 * directly indicate a specific 802.1d priority.  This is used
666 	 * to allow 802.1d priority to be passed directly in from VLAN
667 	 * tags, etc.
668 	 */
669 	if (skb->priority >= 256 && skb->priority <= 263)
670 		return skb->priority - 256;
671 
672 	switch (skb->protocol) {
673 	case htons(ETH_P_IP):
674 		dscp = ipv4_get_dsfield(ip_hdr(skb)) & 0xfc;
675 		break;
676 	case htons(ETH_P_IPV6):
677 		dscp = ipv6_get_dsfield(ipv6_hdr(skb)) & 0xfc;
678 		break;
679 	default:
680 		return 0;
681 	}
682 
683 	return dscp >> 5;
684 }
685 EXPORT_SYMBOL(cfg80211_classify8021d);
686 
687 const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
688 {
689 	if (bss->information_elements == NULL)
690 		return NULL;
691 	return cfg80211_find_ie(ie, bss->information_elements,
692 				 bss->len_information_elements);
693 }
694 EXPORT_SYMBOL(ieee80211_bss_get_ie);
695 
696 void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
697 {
698 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
699 	struct net_device *dev = wdev->netdev;
700 	int i;
701 
702 	if (!wdev->connect_keys)
703 		return;
704 
705 	for (i = 0; i < 6; i++) {
706 		if (!wdev->connect_keys->params[i].cipher)
707 			continue;
708 		if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
709 					&wdev->connect_keys->params[i])) {
710 			netdev_err(dev, "failed to set key %d\n", i);
711 			continue;
712 		}
713 		if (wdev->connect_keys->def == i)
714 			if (rdev->ops->set_default_key(wdev->wiphy, dev,
715 						       i, true, true)) {
716 				netdev_err(dev, "failed to set defkey %d\n", i);
717 				continue;
718 			}
719 		if (wdev->connect_keys->defmgmt == i)
720 			if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
721 				netdev_err(dev, "failed to set mgtdef %d\n", i);
722 	}
723 
724 	kfree(wdev->connect_keys);
725 	wdev->connect_keys = NULL;
726 }
727 
728 void cfg80211_process_wdev_events(struct wireless_dev *wdev)
729 {
730 	struct cfg80211_event *ev;
731 	unsigned long flags;
732 	const u8 *bssid = NULL;
733 
734 	spin_lock_irqsave(&wdev->event_lock, flags);
735 	while (!list_empty(&wdev->event_list)) {
736 		ev = list_first_entry(&wdev->event_list,
737 				      struct cfg80211_event, list);
738 		list_del(&ev->list);
739 		spin_unlock_irqrestore(&wdev->event_lock, flags);
740 
741 		wdev_lock(wdev);
742 		switch (ev->type) {
743 		case EVENT_CONNECT_RESULT:
744 			if (!is_zero_ether_addr(ev->cr.bssid))
745 				bssid = ev->cr.bssid;
746 			__cfg80211_connect_result(
747 				wdev->netdev, bssid,
748 				ev->cr.req_ie, ev->cr.req_ie_len,
749 				ev->cr.resp_ie, ev->cr.resp_ie_len,
750 				ev->cr.status,
751 				ev->cr.status == WLAN_STATUS_SUCCESS,
752 				NULL);
753 			break;
754 		case EVENT_ROAMED:
755 			__cfg80211_roamed(wdev, ev->rm.bss, ev->rm.req_ie,
756 					  ev->rm.req_ie_len, ev->rm.resp_ie,
757 					  ev->rm.resp_ie_len);
758 			break;
759 		case EVENT_DISCONNECTED:
760 			__cfg80211_disconnected(wdev->netdev,
761 						ev->dc.ie, ev->dc.ie_len,
762 						ev->dc.reason, true);
763 			break;
764 		case EVENT_IBSS_JOINED:
765 			__cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
766 			break;
767 		}
768 		wdev_unlock(wdev);
769 
770 		kfree(ev);
771 
772 		spin_lock_irqsave(&wdev->event_lock, flags);
773 	}
774 	spin_unlock_irqrestore(&wdev->event_lock, flags);
775 }
776 
777 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
778 {
779 	struct wireless_dev *wdev;
780 
781 	ASSERT_RTNL();
782 	ASSERT_RDEV_LOCK(rdev);
783 
784 	mutex_lock(&rdev->devlist_mtx);
785 
786 	list_for_each_entry(wdev, &rdev->wdev_list, list)
787 		cfg80211_process_wdev_events(wdev);
788 
789 	mutex_unlock(&rdev->devlist_mtx);
790 }
791 
792 int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
793 			  struct net_device *dev, enum nl80211_iftype ntype,
794 			  u32 *flags, struct vif_params *params)
795 {
796 	int err;
797 	enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
798 
799 	ASSERT_RDEV_LOCK(rdev);
800 
801 	/* don't support changing VLANs, you just re-create them */
802 	if (otype == NL80211_IFTYPE_AP_VLAN)
803 		return -EOPNOTSUPP;
804 
805 	/* cannot change into P2P device type */
806 	if (ntype == NL80211_IFTYPE_P2P_DEVICE)
807 		return -EOPNOTSUPP;
808 
809 	if (!rdev->ops->change_virtual_intf ||
810 	    !(rdev->wiphy.interface_modes & (1 << ntype)))
811 		return -EOPNOTSUPP;
812 
813 	/* if it's part of a bridge, reject changing type to station/ibss */
814 	if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
815 	    (ntype == NL80211_IFTYPE_ADHOC ||
816 	     ntype == NL80211_IFTYPE_STATION ||
817 	     ntype == NL80211_IFTYPE_P2P_CLIENT))
818 		return -EBUSY;
819 
820 	if (ntype != otype && netif_running(dev)) {
821 		mutex_lock(&rdev->devlist_mtx);
822 		err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
823 						    ntype);
824 		mutex_unlock(&rdev->devlist_mtx);
825 		if (err)
826 			return err;
827 
828 		dev->ieee80211_ptr->use_4addr = false;
829 		dev->ieee80211_ptr->mesh_id_up_len = 0;
830 
831 		switch (otype) {
832 		case NL80211_IFTYPE_AP:
833 			cfg80211_stop_ap(rdev, dev);
834 			break;
835 		case NL80211_IFTYPE_ADHOC:
836 			cfg80211_leave_ibss(rdev, dev, false);
837 			break;
838 		case NL80211_IFTYPE_STATION:
839 		case NL80211_IFTYPE_P2P_CLIENT:
840 			cfg80211_disconnect(rdev, dev,
841 					    WLAN_REASON_DEAUTH_LEAVING, true);
842 			break;
843 		case NL80211_IFTYPE_MESH_POINT:
844 			/* mesh should be handled? */
845 			break;
846 		default:
847 			break;
848 		}
849 
850 		cfg80211_process_rdev_events(rdev);
851 	}
852 
853 	err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
854 					     ntype, flags, params);
855 
856 	WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
857 
858 	if (!err && params && params->use_4addr != -1)
859 		dev->ieee80211_ptr->use_4addr = params->use_4addr;
860 
861 	if (!err) {
862 		dev->priv_flags &= ~IFF_DONT_BRIDGE;
863 		switch (ntype) {
864 		case NL80211_IFTYPE_STATION:
865 			if (dev->ieee80211_ptr->use_4addr)
866 				break;
867 			/* fall through */
868 		case NL80211_IFTYPE_P2P_CLIENT:
869 		case NL80211_IFTYPE_ADHOC:
870 			dev->priv_flags |= IFF_DONT_BRIDGE;
871 			break;
872 		case NL80211_IFTYPE_P2P_GO:
873 		case NL80211_IFTYPE_AP:
874 		case NL80211_IFTYPE_AP_VLAN:
875 		case NL80211_IFTYPE_WDS:
876 		case NL80211_IFTYPE_MESH_POINT:
877 			/* bridging OK */
878 			break;
879 		case NL80211_IFTYPE_MONITOR:
880 			/* monitor can't bridge anyway */
881 			break;
882 		case NL80211_IFTYPE_UNSPECIFIED:
883 		case NUM_NL80211_IFTYPES:
884 			/* not happening */
885 			break;
886 		case NL80211_IFTYPE_P2P_DEVICE:
887 			WARN_ON(1);
888 			break;
889 		}
890 	}
891 
892 	if (!err && ntype != otype && netif_running(dev)) {
893 		cfg80211_update_iface_num(rdev, ntype, 1);
894 		cfg80211_update_iface_num(rdev, otype, -1);
895 	}
896 
897 	return err;
898 }
899 
900 static u32 cfg80211_calculate_bitrate_60g(struct rate_info *rate)
901 {
902 	static const u32 __mcs2bitrate[] = {
903 		/* control PHY */
904 		[0] =   275,
905 		/* SC PHY */
906 		[1] =  3850,
907 		[2] =  7700,
908 		[3] =  9625,
909 		[4] = 11550,
910 		[5] = 12512, /* 1251.25 mbps */
911 		[6] = 15400,
912 		[7] = 19250,
913 		[8] = 23100,
914 		[9] = 25025,
915 		[10] = 30800,
916 		[11] = 38500,
917 		[12] = 46200,
918 		/* OFDM PHY */
919 		[13] =  6930,
920 		[14] =  8662, /* 866.25 mbps */
921 		[15] = 13860,
922 		[16] = 17325,
923 		[17] = 20790,
924 		[18] = 27720,
925 		[19] = 34650,
926 		[20] = 41580,
927 		[21] = 45045,
928 		[22] = 51975,
929 		[23] = 62370,
930 		[24] = 67568, /* 6756.75 mbps */
931 		/* LP-SC PHY */
932 		[25] =  6260,
933 		[26] =  8340,
934 		[27] = 11120,
935 		[28] = 12510,
936 		[29] = 16680,
937 		[30] = 22240,
938 		[31] = 25030,
939 	};
940 
941 	if (WARN_ON_ONCE(rate->mcs >= ARRAY_SIZE(__mcs2bitrate)))
942 		return 0;
943 
944 	return __mcs2bitrate[rate->mcs];
945 }
946 
947 u32 cfg80211_calculate_bitrate(struct rate_info *rate)
948 {
949 	int modulation, streams, bitrate;
950 
951 	if (!(rate->flags & RATE_INFO_FLAGS_MCS))
952 		return rate->legacy;
953 	if (rate->flags & RATE_INFO_FLAGS_60G)
954 		return cfg80211_calculate_bitrate_60g(rate);
955 
956 	/* the formula below does only work for MCS values smaller than 32 */
957 	if (WARN_ON_ONCE(rate->mcs >= 32))
958 		return 0;
959 
960 	modulation = rate->mcs & 7;
961 	streams = (rate->mcs >> 3) + 1;
962 
963 	bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
964 			13500000 : 6500000;
965 
966 	if (modulation < 4)
967 		bitrate *= (modulation + 1);
968 	else if (modulation == 4)
969 		bitrate *= (modulation + 2);
970 	else
971 		bitrate *= (modulation + 3);
972 
973 	bitrate *= streams;
974 
975 	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
976 		bitrate = (bitrate / 9) * 10;
977 
978 	/* do NOT round down here */
979 	return (bitrate + 50000) / 100000;
980 }
981 EXPORT_SYMBOL(cfg80211_calculate_bitrate);
982 
983 int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
984 				 u32 beacon_int)
985 {
986 	struct wireless_dev *wdev;
987 	int res = 0;
988 
989 	if (!beacon_int)
990 		return -EINVAL;
991 
992 	mutex_lock(&rdev->devlist_mtx);
993 
994 	list_for_each_entry(wdev, &rdev->wdev_list, list) {
995 		if (!wdev->beacon_interval)
996 			continue;
997 		if (wdev->beacon_interval != beacon_int) {
998 			res = -EINVAL;
999 			break;
1000 		}
1001 	}
1002 
1003 	mutex_unlock(&rdev->devlist_mtx);
1004 
1005 	return res;
1006 }
1007 
1008 int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
1009 				 struct wireless_dev *wdev,
1010 				 enum nl80211_iftype iftype,
1011 				 struct ieee80211_channel *chan,
1012 				 enum cfg80211_chan_mode chanmode)
1013 {
1014 	struct wireless_dev *wdev_iter;
1015 	u32 used_iftypes = BIT(iftype);
1016 	int num[NUM_NL80211_IFTYPES];
1017 	struct ieee80211_channel
1018 			*used_channels[CFG80211_MAX_NUM_DIFFERENT_CHANNELS];
1019 	struct ieee80211_channel *ch;
1020 	enum cfg80211_chan_mode chmode;
1021 	int num_different_channels = 0;
1022 	int total = 1;
1023 	int i, j;
1024 
1025 	ASSERT_RTNL();
1026 	lockdep_assert_held(&rdev->devlist_mtx);
1027 
1028 	/* Always allow software iftypes */
1029 	if (rdev->wiphy.software_iftypes & BIT(iftype))
1030 		return 0;
1031 
1032 	memset(num, 0, sizeof(num));
1033 	memset(used_channels, 0, sizeof(used_channels));
1034 
1035 	num[iftype] = 1;
1036 
1037 	switch (chanmode) {
1038 	case CHAN_MODE_UNDEFINED:
1039 		break;
1040 	case CHAN_MODE_SHARED:
1041 		WARN_ON(!chan);
1042 		used_channels[0] = chan;
1043 		num_different_channels++;
1044 		break;
1045 	case CHAN_MODE_EXCLUSIVE:
1046 		num_different_channels++;
1047 		break;
1048 	}
1049 
1050 	list_for_each_entry(wdev_iter, &rdev->wdev_list, list) {
1051 		if (wdev_iter == wdev)
1052 			continue;
1053 		if (wdev_iter->netdev) {
1054 			if (!netif_running(wdev_iter->netdev))
1055 				continue;
1056 		} else if (wdev_iter->iftype == NL80211_IFTYPE_P2P_DEVICE) {
1057 			if (!wdev_iter->p2p_started)
1058 				continue;
1059 		} else {
1060 			WARN_ON(1);
1061 		}
1062 
1063 		if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))
1064 			continue;
1065 
1066 		/*
1067 		 * We may be holding the "wdev" mutex, but now need to lock
1068 		 * wdev_iter. This is OK because once we get here wdev_iter
1069 		 * is not wdev (tested above), but we need to use the nested
1070 		 * locking for lockdep.
1071 		 */
1072 		mutex_lock_nested(&wdev_iter->mtx, 1);
1073 		__acquire(wdev_iter->mtx);
1074 		cfg80211_get_chan_state(wdev_iter, &ch, &chmode);
1075 		wdev_unlock(wdev_iter);
1076 
1077 		switch (chmode) {
1078 		case CHAN_MODE_UNDEFINED:
1079 			break;
1080 		case CHAN_MODE_SHARED:
1081 			for (i = 0; i < CFG80211_MAX_NUM_DIFFERENT_CHANNELS; i++)
1082 				if (!used_channels[i] || used_channels[i] == ch)
1083 					break;
1084 
1085 			if (i == CFG80211_MAX_NUM_DIFFERENT_CHANNELS)
1086 				return -EBUSY;
1087 
1088 			if (used_channels[i] == NULL) {
1089 				used_channels[i] = ch;
1090 				num_different_channels++;
1091 			}
1092 			break;
1093 		case CHAN_MODE_EXCLUSIVE:
1094 			num_different_channels++;
1095 			break;
1096 		}
1097 
1098 		num[wdev_iter->iftype]++;
1099 		total++;
1100 		used_iftypes |= BIT(wdev_iter->iftype);
1101 	}
1102 
1103 	if (total == 1)
1104 		return 0;
1105 
1106 	for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) {
1107 		const struct ieee80211_iface_combination *c;
1108 		struct ieee80211_iface_limit *limits;
1109 		u32 all_iftypes = 0;
1110 
1111 		c = &rdev->wiphy.iface_combinations[i];
1112 
1113 		if (total > c->max_interfaces)
1114 			continue;
1115 		if (num_different_channels > c->num_different_channels)
1116 			continue;
1117 
1118 		limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
1119 				 GFP_KERNEL);
1120 		if (!limits)
1121 			return -ENOMEM;
1122 
1123 		for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
1124 			if (rdev->wiphy.software_iftypes & BIT(iftype))
1125 				continue;
1126 			for (j = 0; j < c->n_limits; j++) {
1127 				all_iftypes |= limits[j].types;
1128 				if (!(limits[j].types & BIT(iftype)))
1129 					continue;
1130 				if (limits[j].max < num[iftype])
1131 					goto cont;
1132 				limits[j].max -= num[iftype];
1133 			}
1134 		}
1135 
1136 		/*
1137 		 * Finally check that all iftypes that we're currently
1138 		 * using are actually part of this combination. If they
1139 		 * aren't then we can't use this combination and have
1140 		 * to continue to the next.
1141 		 */
1142 		if ((all_iftypes & used_iftypes) != used_iftypes)
1143 			goto cont;
1144 
1145 		/*
1146 		 * This combination covered all interface types and
1147 		 * supported the requested numbers, so we're good.
1148 		 */
1149 		kfree(limits);
1150 		return 0;
1151  cont:
1152 		kfree(limits);
1153 	}
1154 
1155 	return -EBUSY;
1156 }
1157 
1158 int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
1159 			   const u8 *rates, unsigned int n_rates,
1160 			   u32 *mask)
1161 {
1162 	int i, j;
1163 
1164 	if (!sband)
1165 		return -EINVAL;
1166 
1167 	if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
1168 		return -EINVAL;
1169 
1170 	*mask = 0;
1171 
1172 	for (i = 0; i < n_rates; i++) {
1173 		int rate = (rates[i] & 0x7f) * 5;
1174 		bool found = false;
1175 
1176 		for (j = 0; j < sband->n_bitrates; j++) {
1177 			if (sband->bitrates[j].bitrate == rate) {
1178 				found = true;
1179 				*mask |= BIT(j);
1180 				break;
1181 			}
1182 		}
1183 		if (!found)
1184 			return -EINVAL;
1185 	}
1186 
1187 	/*
1188 	 * mask must have at least one bit set here since we
1189 	 * didn't accept a 0-length rates array nor allowed
1190 	 * entries in the array that didn't exist
1191 	 */
1192 
1193 	return 0;
1194 }
1195 
1196 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
1197 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
1198 const unsigned char rfc1042_header[] __aligned(2) =
1199 	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
1200 EXPORT_SYMBOL(rfc1042_header);
1201 
1202 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
1203 const unsigned char bridge_tunnel_header[] __aligned(2) =
1204 	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
1205 EXPORT_SYMBOL(bridge_tunnel_header);
1206