xref: /linux/net/wireless/util.c (revision cc4589ebfae6f8dbb5cf880a0a67eedab3416492)
1 /*
2  * Wireless utility functions
3  *
4  * Copyright 2007-2009	Johannes Berg <johannes@sipsolutions.net>
5  */
6 #include <linux/bitops.h>
7 #include <linux/etherdevice.h>
8 #include <linux/slab.h>
9 #include <net/cfg80211.h>
10 #include <net/ip.h>
11 #include "core.h"
12 
13 struct ieee80211_rate *
14 ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
15 			    u32 basic_rates, int bitrate)
16 {
17 	struct ieee80211_rate *result = &sband->bitrates[0];
18 	int i;
19 
20 	for (i = 0; i < sband->n_bitrates; i++) {
21 		if (!(basic_rates & BIT(i)))
22 			continue;
23 		if (sband->bitrates[i].bitrate > bitrate)
24 			continue;
25 		result = &sband->bitrates[i];
26 	}
27 
28 	return result;
29 }
30 EXPORT_SYMBOL(ieee80211_get_response_rate);
31 
32 int ieee80211_channel_to_frequency(int chan)
33 {
34 	if (chan < 14)
35 		return 2407 + chan * 5;
36 
37 	if (chan == 14)
38 		return 2484;
39 
40 	/* FIXME: 802.11j 17.3.8.3.2 */
41 	return (chan + 1000) * 5;
42 }
43 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
44 
45 int ieee80211_frequency_to_channel(int freq)
46 {
47 	if (freq == 2484)
48 		return 14;
49 
50 	if (freq < 2484)
51 		return (freq - 2407) / 5;
52 
53 	/* FIXME: 802.11j 17.3.8.3.2 */
54 	return freq/5 - 1000;
55 }
56 EXPORT_SYMBOL(ieee80211_frequency_to_channel);
57 
58 struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
59 						  int freq)
60 {
61 	enum ieee80211_band band;
62 	struct ieee80211_supported_band *sband;
63 	int i;
64 
65 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
66 		sband = wiphy->bands[band];
67 
68 		if (!sband)
69 			continue;
70 
71 		for (i = 0; i < sband->n_channels; i++) {
72 			if (sband->channels[i].center_freq == freq)
73 				return &sband->channels[i];
74 		}
75 	}
76 
77 	return NULL;
78 }
79 EXPORT_SYMBOL(__ieee80211_get_channel);
80 
81 static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
82 				     enum ieee80211_band band)
83 {
84 	int i, want;
85 
86 	switch (band) {
87 	case IEEE80211_BAND_5GHZ:
88 		want = 3;
89 		for (i = 0; i < sband->n_bitrates; i++) {
90 			if (sband->bitrates[i].bitrate == 60 ||
91 			    sband->bitrates[i].bitrate == 120 ||
92 			    sband->bitrates[i].bitrate == 240) {
93 				sband->bitrates[i].flags |=
94 					IEEE80211_RATE_MANDATORY_A;
95 				want--;
96 			}
97 		}
98 		WARN_ON(want);
99 		break;
100 	case IEEE80211_BAND_2GHZ:
101 		want = 7;
102 		for (i = 0; i < sband->n_bitrates; i++) {
103 			if (sband->bitrates[i].bitrate == 10) {
104 				sband->bitrates[i].flags |=
105 					IEEE80211_RATE_MANDATORY_B |
106 					IEEE80211_RATE_MANDATORY_G;
107 				want--;
108 			}
109 
110 			if (sband->bitrates[i].bitrate == 20 ||
111 			    sband->bitrates[i].bitrate == 55 ||
112 			    sband->bitrates[i].bitrate == 110 ||
113 			    sband->bitrates[i].bitrate == 60 ||
114 			    sband->bitrates[i].bitrate == 120 ||
115 			    sband->bitrates[i].bitrate == 240) {
116 				sband->bitrates[i].flags |=
117 					IEEE80211_RATE_MANDATORY_G;
118 				want--;
119 			}
120 
121 			if (sband->bitrates[i].bitrate != 10 &&
122 			    sband->bitrates[i].bitrate != 20 &&
123 			    sband->bitrates[i].bitrate != 55 &&
124 			    sband->bitrates[i].bitrate != 110)
125 				sband->bitrates[i].flags |=
126 					IEEE80211_RATE_ERP_G;
127 		}
128 		WARN_ON(want != 0 && want != 3 && want != 6);
129 		break;
130 	case IEEE80211_NUM_BANDS:
131 		WARN_ON(1);
132 		break;
133 	}
134 }
135 
136 void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
137 {
138 	enum ieee80211_band band;
139 
140 	for (band = 0; band < IEEE80211_NUM_BANDS; band++)
141 		if (wiphy->bands[band])
142 			set_mandatory_flags_band(wiphy->bands[band], band);
143 }
144 
145 int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
146 				   struct key_params *params, int key_idx,
147 				   const u8 *mac_addr)
148 {
149 	int i;
150 
151 	if (key_idx > 5)
152 		return -EINVAL;
153 
154 	/*
155 	 * Disallow pairwise keys with non-zero index unless it's WEP
156 	 * (because current deployments use pairwise WEP keys with
157 	 * non-zero indizes but 802.11i clearly specifies to use zero)
158 	 */
159 	if (mac_addr && key_idx &&
160 	    params->cipher != WLAN_CIPHER_SUITE_WEP40 &&
161 	    params->cipher != WLAN_CIPHER_SUITE_WEP104)
162 		return -EINVAL;
163 
164 	switch (params->cipher) {
165 	case WLAN_CIPHER_SUITE_WEP40:
166 		if (params->key_len != WLAN_KEY_LEN_WEP40)
167 			return -EINVAL;
168 		break;
169 	case WLAN_CIPHER_SUITE_TKIP:
170 		if (params->key_len != WLAN_KEY_LEN_TKIP)
171 			return -EINVAL;
172 		break;
173 	case WLAN_CIPHER_SUITE_CCMP:
174 		if (params->key_len != WLAN_KEY_LEN_CCMP)
175 			return -EINVAL;
176 		break;
177 	case WLAN_CIPHER_SUITE_WEP104:
178 		if (params->key_len != WLAN_KEY_LEN_WEP104)
179 			return -EINVAL;
180 		break;
181 	case WLAN_CIPHER_SUITE_AES_CMAC:
182 		if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
183 			return -EINVAL;
184 		break;
185 	default:
186 		return -EINVAL;
187 	}
188 
189 	if (params->seq) {
190 		switch (params->cipher) {
191 		case WLAN_CIPHER_SUITE_WEP40:
192 		case WLAN_CIPHER_SUITE_WEP104:
193 			/* These ciphers do not use key sequence */
194 			return -EINVAL;
195 		case WLAN_CIPHER_SUITE_TKIP:
196 		case WLAN_CIPHER_SUITE_CCMP:
197 		case WLAN_CIPHER_SUITE_AES_CMAC:
198 			if (params->seq_len != 6)
199 				return -EINVAL;
200 			break;
201 		}
202 	}
203 
204 	for (i = 0; i < rdev->wiphy.n_cipher_suites; i++)
205 		if (params->cipher == rdev->wiphy.cipher_suites[i])
206 			break;
207 	if (i == rdev->wiphy.n_cipher_suites)
208 		return -EINVAL;
209 
210 	return 0;
211 }
212 
213 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
214 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
215 const unsigned char rfc1042_header[] __aligned(2) =
216 	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
217 EXPORT_SYMBOL(rfc1042_header);
218 
219 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
220 const unsigned char bridge_tunnel_header[] __aligned(2) =
221 	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
222 EXPORT_SYMBOL(bridge_tunnel_header);
223 
224 unsigned int ieee80211_hdrlen(__le16 fc)
225 {
226 	unsigned int hdrlen = 24;
227 
228 	if (ieee80211_is_data(fc)) {
229 		if (ieee80211_has_a4(fc))
230 			hdrlen = 30;
231 		if (ieee80211_is_data_qos(fc)) {
232 			hdrlen += IEEE80211_QOS_CTL_LEN;
233 			if (ieee80211_has_order(fc))
234 				hdrlen += IEEE80211_HT_CTL_LEN;
235 		}
236 		goto out;
237 	}
238 
239 	if (ieee80211_is_ctl(fc)) {
240 		/*
241 		 * ACK and CTS are 10 bytes, all others 16. To see how
242 		 * to get this condition consider
243 		 *   subtype mask:   0b0000000011110000 (0x00F0)
244 		 *   ACK subtype:    0b0000000011010000 (0x00D0)
245 		 *   CTS subtype:    0b0000000011000000 (0x00C0)
246 		 *   bits that matter:         ^^^      (0x00E0)
247 		 *   value of those: 0b0000000011000000 (0x00C0)
248 		 */
249 		if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
250 			hdrlen = 10;
251 		else
252 			hdrlen = 16;
253 	}
254 out:
255 	return hdrlen;
256 }
257 EXPORT_SYMBOL(ieee80211_hdrlen);
258 
259 unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
260 {
261 	const struct ieee80211_hdr *hdr =
262 			(const struct ieee80211_hdr *)skb->data;
263 	unsigned int hdrlen;
264 
265 	if (unlikely(skb->len < 10))
266 		return 0;
267 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
268 	if (unlikely(hdrlen > skb->len))
269 		return 0;
270 	return hdrlen;
271 }
272 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
273 
274 static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
275 {
276 	int ae = meshhdr->flags & MESH_FLAGS_AE;
277 	/* 7.1.3.5a.2 */
278 	switch (ae) {
279 	case 0:
280 		return 6;
281 	case MESH_FLAGS_AE_A4:
282 		return 12;
283 	case MESH_FLAGS_AE_A5_A6:
284 		return 18;
285 	case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
286 		return 24;
287 	default:
288 		return 6;
289 	}
290 }
291 
292 int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
293 			   enum nl80211_iftype iftype)
294 {
295 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
296 	u16 hdrlen, ethertype;
297 	u8 *payload;
298 	u8 dst[ETH_ALEN];
299 	u8 src[ETH_ALEN] __aligned(2);
300 
301 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
302 		return -1;
303 
304 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
305 
306 	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
307 	 * header
308 	 * IEEE 802.11 address fields:
309 	 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
310 	 *   0     0   DA    SA    BSSID n/a
311 	 *   0     1   DA    BSSID SA    n/a
312 	 *   1     0   BSSID SA    DA    n/a
313 	 *   1     1   RA    TA    DA    SA
314 	 */
315 	memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
316 	memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
317 
318 	switch (hdr->frame_control &
319 		cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
320 	case cpu_to_le16(IEEE80211_FCTL_TODS):
321 		if (unlikely(iftype != NL80211_IFTYPE_AP &&
322 			     iftype != NL80211_IFTYPE_AP_VLAN))
323 			return -1;
324 		break;
325 	case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
326 		if (unlikely(iftype != NL80211_IFTYPE_WDS &&
327 			     iftype != NL80211_IFTYPE_MESH_POINT &&
328 			     iftype != NL80211_IFTYPE_AP_VLAN &&
329 			     iftype != NL80211_IFTYPE_STATION))
330 			return -1;
331 		if (iftype == NL80211_IFTYPE_MESH_POINT) {
332 			struct ieee80211s_hdr *meshdr =
333 				(struct ieee80211s_hdr *) (skb->data + hdrlen);
334 			/* make sure meshdr->flags is on the linear part */
335 			if (!pskb_may_pull(skb, hdrlen + 1))
336 				return -1;
337 			if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
338 				skb_copy_bits(skb, hdrlen +
339 					offsetof(struct ieee80211s_hdr, eaddr1),
340 				       	dst, ETH_ALEN);
341 				skb_copy_bits(skb, hdrlen +
342 					offsetof(struct ieee80211s_hdr, eaddr2),
343 				        src, ETH_ALEN);
344 			}
345 			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
346 		}
347 		break;
348 	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
349 		if ((iftype != NL80211_IFTYPE_STATION &&
350 		    iftype != NL80211_IFTYPE_MESH_POINT) ||
351 		    (is_multicast_ether_addr(dst) &&
352 		     !compare_ether_addr(src, addr)))
353 			return -1;
354 		if (iftype == NL80211_IFTYPE_MESH_POINT) {
355 			struct ieee80211s_hdr *meshdr =
356 				(struct ieee80211s_hdr *) (skb->data + hdrlen);
357 			/* make sure meshdr->flags is on the linear part */
358 			if (!pskb_may_pull(skb, hdrlen + 1))
359 				return -1;
360 			if (meshdr->flags & MESH_FLAGS_AE_A4)
361 				skb_copy_bits(skb, hdrlen +
362 					offsetof(struct ieee80211s_hdr, eaddr1),
363 					src, ETH_ALEN);
364 			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
365 		}
366 		break;
367 	case cpu_to_le16(0):
368 		if (iftype != NL80211_IFTYPE_ADHOC)
369 			return -1;
370 		break;
371 	}
372 
373 	if (!pskb_may_pull(skb, hdrlen + 8))
374 		return -1;
375 
376 	payload = skb->data + hdrlen;
377 	ethertype = (payload[6] << 8) | payload[7];
378 
379 	if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
380 		    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
381 		   compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
382 		/* remove RFC1042 or Bridge-Tunnel encapsulation and
383 		 * replace EtherType */
384 		skb_pull(skb, hdrlen + 6);
385 		memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
386 		memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
387 	} else {
388 		struct ethhdr *ehdr;
389 		__be16 len;
390 
391 		skb_pull(skb, hdrlen);
392 		len = htons(skb->len);
393 		ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
394 		memcpy(ehdr->h_dest, dst, ETH_ALEN);
395 		memcpy(ehdr->h_source, src, ETH_ALEN);
396 		ehdr->h_proto = len;
397 	}
398 	return 0;
399 }
400 EXPORT_SYMBOL(ieee80211_data_to_8023);
401 
402 int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
403 			     enum nl80211_iftype iftype, u8 *bssid, bool qos)
404 {
405 	struct ieee80211_hdr hdr;
406 	u16 hdrlen, ethertype;
407 	__le16 fc;
408 	const u8 *encaps_data;
409 	int encaps_len, skip_header_bytes;
410 	int nh_pos, h_pos;
411 	int head_need;
412 
413 	if (unlikely(skb->len < ETH_HLEN))
414 		return -EINVAL;
415 
416 	nh_pos = skb_network_header(skb) - skb->data;
417 	h_pos = skb_transport_header(skb) - skb->data;
418 
419 	/* convert Ethernet header to proper 802.11 header (based on
420 	 * operation mode) */
421 	ethertype = (skb->data[12] << 8) | skb->data[13];
422 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
423 
424 	switch (iftype) {
425 	case NL80211_IFTYPE_AP:
426 	case NL80211_IFTYPE_AP_VLAN:
427 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
428 		/* DA BSSID SA */
429 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
430 		memcpy(hdr.addr2, addr, ETH_ALEN);
431 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
432 		hdrlen = 24;
433 		break;
434 	case NL80211_IFTYPE_STATION:
435 		fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
436 		/* BSSID SA DA */
437 		memcpy(hdr.addr1, bssid, ETH_ALEN);
438 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
439 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
440 		hdrlen = 24;
441 		break;
442 	case NL80211_IFTYPE_ADHOC:
443 		/* DA SA BSSID */
444 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
445 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
446 		memcpy(hdr.addr3, bssid, ETH_ALEN);
447 		hdrlen = 24;
448 		break;
449 	default:
450 		return -EOPNOTSUPP;
451 	}
452 
453 	if (qos) {
454 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
455 		hdrlen += 2;
456 	}
457 
458 	hdr.frame_control = fc;
459 	hdr.duration_id = 0;
460 	hdr.seq_ctrl = 0;
461 
462 	skip_header_bytes = ETH_HLEN;
463 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
464 		encaps_data = bridge_tunnel_header;
465 		encaps_len = sizeof(bridge_tunnel_header);
466 		skip_header_bytes -= 2;
467 	} else if (ethertype > 0x600) {
468 		encaps_data = rfc1042_header;
469 		encaps_len = sizeof(rfc1042_header);
470 		skip_header_bytes -= 2;
471 	} else {
472 		encaps_data = NULL;
473 		encaps_len = 0;
474 	}
475 
476 	skb_pull(skb, skip_header_bytes);
477 	nh_pos -= skip_header_bytes;
478 	h_pos -= skip_header_bytes;
479 
480 	head_need = hdrlen + encaps_len - skb_headroom(skb);
481 
482 	if (head_need > 0 || skb_cloned(skb)) {
483 		head_need = max(head_need, 0);
484 		if (head_need)
485 			skb_orphan(skb);
486 
487 		if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC)) {
488 			printk(KERN_ERR "failed to reallocate Tx buffer\n");
489 			return -ENOMEM;
490 		}
491 		skb->truesize += head_need;
492 	}
493 
494 	if (encaps_data) {
495 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
496 		nh_pos += encaps_len;
497 		h_pos += encaps_len;
498 	}
499 
500 	memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
501 
502 	nh_pos += hdrlen;
503 	h_pos += hdrlen;
504 
505 	/* Update skb pointers to various headers since this modified frame
506 	 * is going to go through Linux networking code that may potentially
507 	 * need things like pointer to IP header. */
508 	skb_set_mac_header(skb, 0);
509 	skb_set_network_header(skb, nh_pos);
510 	skb_set_transport_header(skb, h_pos);
511 
512 	return 0;
513 }
514 EXPORT_SYMBOL(ieee80211_data_from_8023);
515 
516 
517 void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
518 			      const u8 *addr, enum nl80211_iftype iftype,
519 			      const unsigned int extra_headroom)
520 {
521 	struct sk_buff *frame = NULL;
522 	u16 ethertype;
523 	u8 *payload;
524 	const struct ethhdr *eth;
525 	int remaining, err;
526 	u8 dst[ETH_ALEN], src[ETH_ALEN];
527 
528 	err = ieee80211_data_to_8023(skb, addr, iftype);
529 	if (err)
530 		goto out;
531 
532 	/* skip the wrapping header */
533 	eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
534 	if (!eth)
535 		goto out;
536 
537 	while (skb != frame) {
538 		u8 padding;
539 		__be16 len = eth->h_proto;
540 		unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
541 
542 		remaining = skb->len;
543 		memcpy(dst, eth->h_dest, ETH_ALEN);
544 		memcpy(src, eth->h_source, ETH_ALEN);
545 
546 		padding = (4 - subframe_len) & 0x3;
547 		/* the last MSDU has no padding */
548 		if (subframe_len > remaining)
549 			goto purge;
550 
551 		skb_pull(skb, sizeof(struct ethhdr));
552 		/* reuse skb for the last subframe */
553 		if (remaining <= subframe_len + padding)
554 			frame = skb;
555 		else {
556 			unsigned int hlen = ALIGN(extra_headroom, 4);
557 			/*
558 			 * Allocate and reserve two bytes more for payload
559 			 * alignment since sizeof(struct ethhdr) is 14.
560 			 */
561 			frame = dev_alloc_skb(hlen + subframe_len + 2);
562 			if (!frame)
563 				goto purge;
564 
565 			skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
566 			memcpy(skb_put(frame, ntohs(len)), skb->data,
567 				ntohs(len));
568 
569 			eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
570 							padding);
571 			if (!eth) {
572 				dev_kfree_skb(frame);
573 				goto purge;
574 			}
575 		}
576 
577 		skb_reset_network_header(frame);
578 		frame->dev = skb->dev;
579 		frame->priority = skb->priority;
580 
581 		payload = frame->data;
582 		ethertype = (payload[6] << 8) | payload[7];
583 
584 		if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
585 			    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
586 			   compare_ether_addr(payload,
587 					      bridge_tunnel_header) == 0)) {
588 			/* remove RFC1042 or Bridge-Tunnel
589 			 * encapsulation and replace EtherType */
590 			skb_pull(frame, 6);
591 			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
592 			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
593 		} else {
594 			memcpy(skb_push(frame, sizeof(__be16)), &len,
595 				sizeof(__be16));
596 			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
597 			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
598 		}
599 		__skb_queue_tail(list, frame);
600 	}
601 
602 	return;
603 
604  purge:
605 	__skb_queue_purge(list);
606  out:
607 	dev_kfree_skb(skb);
608 }
609 EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
610 
611 /* Given a data frame determine the 802.1p/1d tag to use. */
612 unsigned int cfg80211_classify8021d(struct sk_buff *skb)
613 {
614 	unsigned int dscp;
615 
616 	/* skb->priority values from 256->263 are magic values to
617 	 * directly indicate a specific 802.1d priority.  This is used
618 	 * to allow 802.1d priority to be passed directly in from VLAN
619 	 * tags, etc.
620 	 */
621 	if (skb->priority >= 256 && skb->priority <= 263)
622 		return skb->priority - 256;
623 
624 	switch (skb->protocol) {
625 	case htons(ETH_P_IP):
626 		dscp = ip_hdr(skb)->tos & 0xfc;
627 		break;
628 	default:
629 		return 0;
630 	}
631 
632 	return dscp >> 5;
633 }
634 EXPORT_SYMBOL(cfg80211_classify8021d);
635 
636 const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
637 {
638 	u8 *end, *pos;
639 
640 	pos = bss->information_elements;
641 	if (pos == NULL)
642 		return NULL;
643 	end = pos + bss->len_information_elements;
644 
645 	while (pos + 1 < end) {
646 		if (pos + 2 + pos[1] > end)
647 			break;
648 		if (pos[0] == ie)
649 			return pos;
650 		pos += 2 + pos[1];
651 	}
652 
653 	return NULL;
654 }
655 EXPORT_SYMBOL(ieee80211_bss_get_ie);
656 
657 void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
658 {
659 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
660 	struct net_device *dev = wdev->netdev;
661 	int i;
662 
663 	if (!wdev->connect_keys)
664 		return;
665 
666 	for (i = 0; i < 6; i++) {
667 		if (!wdev->connect_keys->params[i].cipher)
668 			continue;
669 		if (rdev->ops->add_key(wdev->wiphy, dev, i, NULL,
670 					&wdev->connect_keys->params[i])) {
671 			printk(KERN_ERR "%s: failed to set key %d\n",
672 				dev->name, i);
673 			continue;
674 		}
675 		if (wdev->connect_keys->def == i)
676 			if (rdev->ops->set_default_key(wdev->wiphy, dev, i)) {
677 				printk(KERN_ERR "%s: failed to set defkey %d\n",
678 					dev->name, i);
679 				continue;
680 			}
681 		if (wdev->connect_keys->defmgmt == i)
682 			if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
683 				printk(KERN_ERR "%s: failed to set mgtdef %d\n",
684 					dev->name, i);
685 	}
686 
687 	kfree(wdev->connect_keys);
688 	wdev->connect_keys = NULL;
689 }
690 
691 static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
692 {
693 	struct cfg80211_event *ev;
694 	unsigned long flags;
695 	const u8 *bssid = NULL;
696 
697 	spin_lock_irqsave(&wdev->event_lock, flags);
698 	while (!list_empty(&wdev->event_list)) {
699 		ev = list_first_entry(&wdev->event_list,
700 				      struct cfg80211_event, list);
701 		list_del(&ev->list);
702 		spin_unlock_irqrestore(&wdev->event_lock, flags);
703 
704 		wdev_lock(wdev);
705 		switch (ev->type) {
706 		case EVENT_CONNECT_RESULT:
707 			if (!is_zero_ether_addr(ev->cr.bssid))
708 				bssid = ev->cr.bssid;
709 			__cfg80211_connect_result(
710 				wdev->netdev, bssid,
711 				ev->cr.req_ie, ev->cr.req_ie_len,
712 				ev->cr.resp_ie, ev->cr.resp_ie_len,
713 				ev->cr.status,
714 				ev->cr.status == WLAN_STATUS_SUCCESS,
715 				NULL);
716 			break;
717 		case EVENT_ROAMED:
718 			__cfg80211_roamed(wdev, ev->rm.bssid,
719 					  ev->rm.req_ie, ev->rm.req_ie_len,
720 					  ev->rm.resp_ie, ev->rm.resp_ie_len);
721 			break;
722 		case EVENT_DISCONNECTED:
723 			__cfg80211_disconnected(wdev->netdev,
724 						ev->dc.ie, ev->dc.ie_len,
725 						ev->dc.reason, true);
726 			break;
727 		case EVENT_IBSS_JOINED:
728 			__cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
729 			break;
730 		}
731 		wdev_unlock(wdev);
732 
733 		kfree(ev);
734 
735 		spin_lock_irqsave(&wdev->event_lock, flags);
736 	}
737 	spin_unlock_irqrestore(&wdev->event_lock, flags);
738 }
739 
740 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
741 {
742 	struct wireless_dev *wdev;
743 
744 	ASSERT_RTNL();
745 	ASSERT_RDEV_LOCK(rdev);
746 
747 	mutex_lock(&rdev->devlist_mtx);
748 
749 	list_for_each_entry(wdev, &rdev->netdev_list, list)
750 		cfg80211_process_wdev_events(wdev);
751 
752 	mutex_unlock(&rdev->devlist_mtx);
753 }
754 
755 int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
756 			  struct net_device *dev, enum nl80211_iftype ntype,
757 			  u32 *flags, struct vif_params *params)
758 {
759 	int err;
760 	enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
761 
762 	ASSERT_RDEV_LOCK(rdev);
763 
764 	/* don't support changing VLANs, you just re-create them */
765 	if (otype == NL80211_IFTYPE_AP_VLAN)
766 		return -EOPNOTSUPP;
767 
768 	if (!rdev->ops->change_virtual_intf ||
769 	    !(rdev->wiphy.interface_modes & (1 << ntype)))
770 		return -EOPNOTSUPP;
771 
772 	/* if it's part of a bridge, reject changing type to station/ibss */
773 	if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
774 	    (ntype == NL80211_IFTYPE_ADHOC || ntype == NL80211_IFTYPE_STATION))
775 		return -EBUSY;
776 
777 	if (ntype != otype) {
778 		dev->ieee80211_ptr->use_4addr = false;
779 
780 		switch (otype) {
781 		case NL80211_IFTYPE_ADHOC:
782 			cfg80211_leave_ibss(rdev, dev, false);
783 			break;
784 		case NL80211_IFTYPE_STATION:
785 			cfg80211_disconnect(rdev, dev,
786 					    WLAN_REASON_DEAUTH_LEAVING, true);
787 			break;
788 		case NL80211_IFTYPE_MESH_POINT:
789 			/* mesh should be handled? */
790 			break;
791 		default:
792 			break;
793 		}
794 
795 		cfg80211_process_rdev_events(rdev);
796 	}
797 
798 	err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
799 					     ntype, flags, params);
800 
801 	WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
802 
803 	if (!err && params && params->use_4addr != -1)
804 		dev->ieee80211_ptr->use_4addr = params->use_4addr;
805 
806 	if (!err) {
807 		dev->priv_flags &= ~IFF_DONT_BRIDGE;
808 		switch (ntype) {
809 		case NL80211_IFTYPE_STATION:
810 			if (dev->ieee80211_ptr->use_4addr)
811 				break;
812 			/* fall through */
813 		case NL80211_IFTYPE_ADHOC:
814 			dev->priv_flags |= IFF_DONT_BRIDGE;
815 			break;
816 		case NL80211_IFTYPE_AP:
817 		case NL80211_IFTYPE_AP_VLAN:
818 		case NL80211_IFTYPE_WDS:
819 		case NL80211_IFTYPE_MESH_POINT:
820 			/* bridging OK */
821 			break;
822 		case NL80211_IFTYPE_MONITOR:
823 			/* monitor can't bridge anyway */
824 			break;
825 		case NL80211_IFTYPE_UNSPECIFIED:
826 		case __NL80211_IFTYPE_AFTER_LAST:
827 			/* not happening */
828 			break;
829 		}
830 	}
831 
832 	return err;
833 }
834 
835 u16 cfg80211_calculate_bitrate(struct rate_info *rate)
836 {
837 	int modulation, streams, bitrate;
838 
839 	if (!(rate->flags & RATE_INFO_FLAGS_MCS))
840 		return rate->legacy;
841 
842 	/* the formula below does only work for MCS values smaller than 32 */
843 	if (rate->mcs >= 32)
844 		return 0;
845 
846 	modulation = rate->mcs & 7;
847 	streams = (rate->mcs >> 3) + 1;
848 
849 	bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
850 			13500000 : 6500000;
851 
852 	if (modulation < 4)
853 		bitrate *= (modulation + 1);
854 	else if (modulation == 4)
855 		bitrate *= (modulation + 2);
856 	else
857 		bitrate *= (modulation + 3);
858 
859 	bitrate *= streams;
860 
861 	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
862 		bitrate = (bitrate / 9) * 10;
863 
864 	/* do NOT round down here */
865 	return (bitrate + 50000) / 100000;
866 }
867