util.c 22.7 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898
/*
 * Wireless utility functions
 *
 * Copyright 2007-2009	Johannes Berg <johannes@sipsolutions.net>
 */
#include <linux/bitops.h>
#include <linux/etherdevice.h>
#include <linux/slab.h>
#include <net/cfg80211.h>
#include <net/ip.h>
#include "core.h"

struct ieee80211_rate *
ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
			    u32 basic_rates, int bitrate)
{
	struct ieee80211_rate *result = &sband->bitrates[0];
	int i;

	for (i = 0; i < sband->n_bitrates; i++) {
		if (!(basic_rates & BIT(i)))
			continue;
		if (sband->bitrates[i].bitrate > bitrate)
			continue;
		result = &sband->bitrates[i];
	}

	return result;
}
EXPORT_SYMBOL(ieee80211_get_response_rate);

int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
{
	/* see 802.11 17.3.8.3.2 and Annex J
	 * there are overlapping channel numbers in 5GHz and 2GHz bands */
	if (band == IEEE80211_BAND_5GHZ) {
		if (chan >= 182 && chan <= 196)
			return 4000 + chan * 5;
		else
			return 5000 + chan * 5;
	} else { /* IEEE80211_BAND_2GHZ */
		if (chan == 14)
			return 2484;
		else if (chan < 14)
			return 2407 + chan * 5;
		else
			return 0; /* not supported */
	}
}
EXPORT_SYMBOL(ieee80211_channel_to_frequency);

int ieee80211_frequency_to_channel(int freq)
{
	/* see 802.11 17.3.8.3.2 and Annex J */
	if (freq == 2484)
		return 14;
	else if (freq < 2484)
		return (freq - 2407) / 5;
	else if (freq >= 4910 && freq <= 4980)
		return (freq - 4000) / 5;
	else
		return (freq - 5000) / 5;
}
EXPORT_SYMBOL(ieee80211_frequency_to_channel);

struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
						  int freq)
{
	enum ieee80211_band band;
	struct ieee80211_supported_band *sband;
	int i;

	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
		sband = wiphy->bands[band];

		if (!sband)
			continue;

		for (i = 0; i < sband->n_channels; i++) {
			if (sband->channels[i].center_freq == freq)
				return &sband->channels[i];
		}
	}

	return NULL;
}
EXPORT_SYMBOL(__ieee80211_get_channel);

static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
				     enum ieee80211_band band)
{
	int i, want;

	switch (band) {
	case IEEE80211_BAND_5GHZ:
		want = 3;
		for (i = 0; i < sband->n_bitrates; i++) {
			if (sband->bitrates[i].bitrate == 60 ||
			    sband->bitrates[i].bitrate == 120 ||
			    sband->bitrates[i].bitrate == 240) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_A;
				want--;
			}
		}
		WARN_ON(want);
		break;
	case IEEE80211_BAND_2GHZ:
		want = 7;
		for (i = 0; i < sband->n_bitrates; i++) {
			if (sband->bitrates[i].bitrate == 10) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_B |
					IEEE80211_RATE_MANDATORY_G;
				want--;
			}

			if (sband->bitrates[i].bitrate == 20 ||
			    sband->bitrates[i].bitrate == 55 ||
			    sband->bitrates[i].bitrate == 110 ||
			    sband->bitrates[i].bitrate == 60 ||
			    sband->bitrates[i].bitrate == 120 ||
			    sband->bitrates[i].bitrate == 240) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_G;
				want--;
			}

			if (sband->bitrates[i].bitrate != 10 &&
			    sband->bitrates[i].bitrate != 20 &&
			    sband->bitrates[i].bitrate != 55 &&
			    sband->bitrates[i].bitrate != 110)
				sband->bitrates[i].flags |=
					IEEE80211_RATE_ERP_G;
		}
		WARN_ON(want != 0 && want != 3 && want != 6);
		break;
	case IEEE80211_NUM_BANDS:
		WARN_ON(1);
		break;
	}
}

void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
{
	enum ieee80211_band band;

	for (band = 0; band < IEEE80211_NUM_BANDS; band++)
		if (wiphy->bands[band])
			set_mandatory_flags_band(wiphy->bands[band], band);
}

int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
				   struct key_params *params, int key_idx,
				   bool pairwise, const u8 *mac_addr)
{
	int i;

	if (key_idx > 5)
		return -EINVAL;

	if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
		return -EINVAL;

	if (pairwise && !mac_addr)
		return -EINVAL;

	/*
	 * Disallow pairwise keys with non-zero index unless it's WEP
	 * or a vendor specific cipher (because current deployments use
	 * pairwise WEP keys with non-zero indices and for vendor specific
	 * ciphers this should be validated in the driver or hardware level
	 * - but 802.11i clearly specifies to use zero)
	 */
	if (pairwise && key_idx &&
	    ((params->cipher == WLAN_CIPHER_SUITE_TKIP) ||
	     (params->cipher == WLAN_CIPHER_SUITE_CCMP) ||
	     (params->cipher == WLAN_CIPHER_SUITE_AES_CMAC)))
		return -EINVAL;

	switch (params->cipher) {
	case WLAN_CIPHER_SUITE_WEP40:
		if (params->key_len != WLAN_KEY_LEN_WEP40)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_TKIP:
		if (params->key_len != WLAN_KEY_LEN_TKIP)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_CCMP:
		if (params->key_len != WLAN_KEY_LEN_CCMP)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_WEP104:
		if (params->key_len != WLAN_KEY_LEN_WEP104)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_AES_CMAC:
		if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
			return -EINVAL;
		break;
	default:
		/*
		 * We don't know anything about this algorithm,
		 * allow using it -- but the driver must check
		 * all parameters! We still check below whether
		 * or not the driver supports this algorithm,
		 * of course.
		 */
		break;
	}

	if (params->seq) {
		switch (params->cipher) {
		case WLAN_CIPHER_SUITE_WEP40:
		case WLAN_CIPHER_SUITE_WEP104:
			/* These ciphers do not use key sequence */
			return -EINVAL;
		case WLAN_CIPHER_SUITE_TKIP:
		case WLAN_CIPHER_SUITE_CCMP:
		case WLAN_CIPHER_SUITE_AES_CMAC:
			if (params->seq_len != 6)
				return -EINVAL;
			break;
		}
	}

	for (i = 0; i < rdev->wiphy.n_cipher_suites; i++)
		if (params->cipher == rdev->wiphy.cipher_suites[i])
			break;
	if (i == rdev->wiphy.n_cipher_suites)
		return -EINVAL;

	return 0;
}

/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
const unsigned char rfc1042_header[] __aligned(2) =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
EXPORT_SYMBOL(rfc1042_header);

/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
const unsigned char bridge_tunnel_header[] __aligned(2) =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
EXPORT_SYMBOL(bridge_tunnel_header);

unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
{
	unsigned int hdrlen = 24;

	if (ieee80211_is_data(fc)) {
		if (ieee80211_has_a4(fc))
			hdrlen = 30;
		if (ieee80211_is_data_qos(fc)) {
			hdrlen += IEEE80211_QOS_CTL_LEN;
			if (ieee80211_has_order(fc))
				hdrlen += IEEE80211_HT_CTL_LEN;
		}
		goto out;
	}

	if (ieee80211_is_ctl(fc)) {
		/*
		 * ACK and CTS are 10 bytes, all others 16. To see how
		 * to get this condition consider
		 *   subtype mask:   0b0000000011110000 (0x00F0)
		 *   ACK subtype:    0b0000000011010000 (0x00D0)
		 *   CTS subtype:    0b0000000011000000 (0x00C0)
		 *   bits that matter:         ^^^      (0x00E0)
		 *   value of those: 0b0000000011000000 (0x00C0)
		 */
		if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
			hdrlen = 10;
		else
			hdrlen = 16;
	}
out:
	return hdrlen;
}
EXPORT_SYMBOL(ieee80211_hdrlen);

unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
{
	const struct ieee80211_hdr *hdr =
			(const struct ieee80211_hdr *)skb->data;
	unsigned int hdrlen;

	if (unlikely(skb->len < 10))
		return 0;
	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	if (unlikely(hdrlen > skb->len))
		return 0;
	return hdrlen;
}
EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);

static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
{
	int ae = meshhdr->flags & MESH_FLAGS_AE;
	/* 7.1.3.5a.2 */
	switch (ae) {
	case 0:
		return 6;
	case MESH_FLAGS_AE_A4:
		return 12;
	case MESH_FLAGS_AE_A5_A6:
		return 18;
	case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
		return 24;
	default:
		return 6;
	}
}

int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
			   enum nl80211_iftype iftype)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	u16 hdrlen, ethertype;
	u8 *payload;
	u8 dst[ETH_ALEN];
	u8 src[ETH_ALEN] __aligned(2);

	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
		return -1;

	hdrlen = ieee80211_hdrlen(hdr->frame_control);

	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
	 * header
	 * IEEE 802.11 address fields:
	 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
	 *   0     0   DA    SA    BSSID n/a
	 *   0     1   DA    BSSID SA    n/a
	 *   1     0   BSSID SA    DA    n/a
	 *   1     1   RA    TA    DA    SA
	 */
	memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
	memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);

	switch (hdr->frame_control &
		cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
	case cpu_to_le16(IEEE80211_FCTL_TODS):
		if (unlikely(iftype != NL80211_IFTYPE_AP &&
			     iftype != NL80211_IFTYPE_AP_VLAN &&
			     iftype != NL80211_IFTYPE_P2P_GO))
			return -1;
		break;
	case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
		if (unlikely(iftype != NL80211_IFTYPE_WDS &&
			     iftype != NL80211_IFTYPE_MESH_POINT &&
			     iftype != NL80211_IFTYPE_AP_VLAN &&
			     iftype != NL80211_IFTYPE_STATION))
			return -1;
		if (iftype == NL80211_IFTYPE_MESH_POINT) {
			struct ieee80211s_hdr *meshdr =
				(struct ieee80211s_hdr *) (skb->data + hdrlen);
			/* make sure meshdr->flags is on the linear part */
			if (!pskb_may_pull(skb, hdrlen + 1))
				return -1;
			if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
				skb_copy_bits(skb, hdrlen +
					offsetof(struct ieee80211s_hdr, eaddr1),
				       	dst, ETH_ALEN);
				skb_copy_bits(skb, hdrlen +
					offsetof(struct ieee80211s_hdr, eaddr2),
				        src, ETH_ALEN);
			}
			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
		}
		break;
	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
		if ((iftype != NL80211_IFTYPE_STATION &&
		     iftype != NL80211_IFTYPE_P2P_CLIENT &&
		     iftype != NL80211_IFTYPE_MESH_POINT) ||
		    (is_multicast_ether_addr(dst) &&
		     !compare_ether_addr(src, addr)))
			return -1;
		if (iftype == NL80211_IFTYPE_MESH_POINT) {
			struct ieee80211s_hdr *meshdr =
				(struct ieee80211s_hdr *) (skb->data + hdrlen);
			/* make sure meshdr->flags is on the linear part */
			if (!pskb_may_pull(skb, hdrlen + 1))
				return -1;
			if (meshdr->flags & MESH_FLAGS_AE_A4)
				skb_copy_bits(skb, hdrlen +
					offsetof(struct ieee80211s_hdr, eaddr1),
					src, ETH_ALEN);
			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
		}
		break;
	case cpu_to_le16(0):
		if (iftype != NL80211_IFTYPE_ADHOC)
			return -1;
		break;
	}

	if (!pskb_may_pull(skb, hdrlen + 8))
		return -1;

	payload = skb->data + hdrlen;
	ethertype = (payload[6] << 8) | payload[7];

	if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
		    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
		   compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
		/* remove RFC1042 or Bridge-Tunnel encapsulation and
		 * replace EtherType */
		skb_pull(skb, hdrlen + 6);
		memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
		memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
	} else {
		struct ethhdr *ehdr;
		__be16 len;

		skb_pull(skb, hdrlen);
		len = htons(skb->len);
		ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
		memcpy(ehdr->h_dest, dst, ETH_ALEN);
		memcpy(ehdr->h_source, src, ETH_ALEN);
		ehdr->h_proto = len;
	}
	return 0;
}
EXPORT_SYMBOL(ieee80211_data_to_8023);

int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
			     enum nl80211_iftype iftype, u8 *bssid, bool qos)
{
	struct ieee80211_hdr hdr;
	u16 hdrlen, ethertype;
	__le16 fc;
	const u8 *encaps_data;
	int encaps_len, skip_header_bytes;
	int nh_pos, h_pos;
	int head_need;

	if (unlikely(skb->len < ETH_HLEN))
		return -EINVAL;

	nh_pos = skb_network_header(skb) - skb->data;
	h_pos = skb_transport_header(skb) - skb->data;

	/* convert Ethernet header to proper 802.11 header (based on
	 * operation mode) */
	ethertype = (skb->data[12] << 8) | skb->data[13];
	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);

	switch (iftype) {
	case NL80211_IFTYPE_AP:
	case NL80211_IFTYPE_AP_VLAN:
	case NL80211_IFTYPE_P2P_GO:
		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
		/* DA BSSID SA */
		memcpy(hdr.addr1, skb->data, ETH_ALEN);
		memcpy(hdr.addr2, addr, ETH_ALEN);
		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
		hdrlen = 24;
		break;
	case NL80211_IFTYPE_STATION:
	case NL80211_IFTYPE_P2P_CLIENT:
		fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
		/* BSSID SA DA */
		memcpy(hdr.addr1, bssid, ETH_ALEN);
		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
		memcpy(hdr.addr3, skb->data, ETH_ALEN);
		hdrlen = 24;
		break;
	case NL80211_IFTYPE_ADHOC:
		/* DA SA BSSID */
		memcpy(hdr.addr1, skb->data, ETH_ALEN);
		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
		memcpy(hdr.addr3, bssid, ETH_ALEN);
		hdrlen = 24;
		break;
	default:
		return -EOPNOTSUPP;
	}

	if (qos) {
		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
		hdrlen += 2;
	}

	hdr.frame_control = fc;
	hdr.duration_id = 0;
	hdr.seq_ctrl = 0;

	skip_header_bytes = ETH_HLEN;
	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
		encaps_data = bridge_tunnel_header;
		encaps_len = sizeof(bridge_tunnel_header);
		skip_header_bytes -= 2;
	} else if (ethertype > 0x600) {
		encaps_data = rfc1042_header;
		encaps_len = sizeof(rfc1042_header);
		skip_header_bytes -= 2;
	} else {
		encaps_data = NULL;
		encaps_len = 0;
	}

	skb_pull(skb, skip_header_bytes);
	nh_pos -= skip_header_bytes;
	h_pos -= skip_header_bytes;

	head_need = hdrlen + encaps_len - skb_headroom(skb);

	if (head_need > 0 || skb_cloned(skb)) {
		head_need = max(head_need, 0);
		if (head_need)
			skb_orphan(skb);

		if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC)) {
			pr_err("failed to reallocate Tx buffer\n");
			return -ENOMEM;
		}
		skb->truesize += head_need;
	}

	if (encaps_data) {
		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
		nh_pos += encaps_len;
		h_pos += encaps_len;
	}

	memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);

	nh_pos += hdrlen;
	h_pos += hdrlen;

	/* Update skb pointers to various headers since this modified frame
	 * is going to go through Linux networking code that may potentially
	 * need things like pointer to IP header. */
	skb_set_mac_header(skb, 0);
	skb_set_network_header(skb, nh_pos);
	skb_set_transport_header(skb, h_pos);

	return 0;
}
EXPORT_SYMBOL(ieee80211_data_from_8023);


void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
			      const u8 *addr, enum nl80211_iftype iftype,
			      const unsigned int extra_headroom)
{
	struct sk_buff *frame = NULL;
	u16 ethertype;
	u8 *payload;
	const struct ethhdr *eth;
	int remaining, err;
	u8 dst[ETH_ALEN], src[ETH_ALEN];

	err = ieee80211_data_to_8023(skb, addr, iftype);
	if (err)
		goto out;

	/* skip the wrapping header */
	eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
	if (!eth)
		goto out;

	while (skb != frame) {
		u8 padding;
		__be16 len = eth->h_proto;
		unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);

		remaining = skb->len;
		memcpy(dst, eth->h_dest, ETH_ALEN);
		memcpy(src, eth->h_source, ETH_ALEN);

		padding = (4 - subframe_len) & 0x3;
		/* the last MSDU has no padding */
		if (subframe_len > remaining)
			goto purge;

		skb_pull(skb, sizeof(struct ethhdr));
		/* reuse skb for the last subframe */
		if (remaining <= subframe_len + padding)
			frame = skb;
		else {
			unsigned int hlen = ALIGN(extra_headroom, 4);
			/*
			 * Allocate and reserve two bytes more for payload
			 * alignment since sizeof(struct ethhdr) is 14.
			 */
			frame = dev_alloc_skb(hlen + subframe_len + 2);
			if (!frame)
				goto purge;

			skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
			memcpy(skb_put(frame, ntohs(len)), skb->data,
				ntohs(len));

			eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
							padding);
			if (!eth) {
				dev_kfree_skb(frame);
				goto purge;
			}
		}

		skb_reset_network_header(frame);
		frame->dev = skb->dev;
		frame->priority = skb->priority;

		payload = frame->data;
		ethertype = (payload[6] << 8) | payload[7];

		if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
			    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
			   compare_ether_addr(payload,
					      bridge_tunnel_header) == 0)) {
			/* remove RFC1042 or Bridge-Tunnel
			 * encapsulation and replace EtherType */
			skb_pull(frame, 6);
			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
		} else {
			memcpy(skb_push(frame, sizeof(__be16)), &len,
				sizeof(__be16));
			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
		}
		__skb_queue_tail(list, frame);
	}

	return;

 purge:
	__skb_queue_purge(list);
 out:
	dev_kfree_skb(skb);
}
EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);

/* Given a data frame determine the 802.1p/1d tag to use. */
unsigned int cfg80211_classify8021d(struct sk_buff *skb)
{
	unsigned int dscp;

	/* skb->priority values from 256->263 are magic values to
	 * directly indicate a specific 802.1d priority.  This is used
	 * to allow 802.1d priority to be passed directly in from VLAN
	 * tags, etc.
	 */
	if (skb->priority >= 256 && skb->priority <= 263)
		return skb->priority - 256;

	switch (skb->protocol) {
	case htons(ETH_P_IP):
		dscp = ip_hdr(skb)->tos & 0xfc;
		break;
	default:
		return 0;
	}

	return dscp >> 5;
}
EXPORT_SYMBOL(cfg80211_classify8021d);

const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
{
	u8 *end, *pos;

	pos = bss->information_elements;
	if (pos == NULL)
		return NULL;
	end = pos + bss->len_information_elements;

	while (pos + 1 < end) {
		if (pos + 2 + pos[1] > end)
			break;
		if (pos[0] == ie)
			return pos;
		pos += 2 + pos[1];
	}

	return NULL;
}
EXPORT_SYMBOL(ieee80211_bss_get_ie);

void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
{
	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
	struct net_device *dev = wdev->netdev;
	int i;

	if (!wdev->connect_keys)
		return;

	for (i = 0; i < 6; i++) {
		if (!wdev->connect_keys->params[i].cipher)
			continue;
		if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
					&wdev->connect_keys->params[i])) {
			netdev_err(dev, "failed to set key %d\n", i);
			continue;
		}
		if (wdev->connect_keys->def == i)
			if (rdev->ops->set_default_key(wdev->wiphy, dev,
						       i, true, true)) {
				netdev_err(dev, "failed to set defkey %d\n", i);
				continue;
			}
		if (wdev->connect_keys->defmgmt == i)
			if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
				netdev_err(dev, "failed to set mgtdef %d\n", i);
	}

	kfree(wdev->connect_keys);
	wdev->connect_keys = NULL;
}

static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
{
	struct cfg80211_event *ev;
	unsigned long flags;
	const u8 *bssid = NULL;

	spin_lock_irqsave(&wdev->event_lock, flags);
	while (!list_empty(&wdev->event_list)) {
		ev = list_first_entry(&wdev->event_list,
				      struct cfg80211_event, list);
		list_del(&ev->list);
		spin_unlock_irqrestore(&wdev->event_lock, flags);

		wdev_lock(wdev);
		switch (ev->type) {
		case EVENT_CONNECT_RESULT:
			if (!is_zero_ether_addr(ev->cr.bssid))
				bssid = ev->cr.bssid;
			__cfg80211_connect_result(
				wdev->netdev, bssid,
				ev->cr.req_ie, ev->cr.req_ie_len,
				ev->cr.resp_ie, ev->cr.resp_ie_len,
				ev->cr.status,
				ev->cr.status == WLAN_STATUS_SUCCESS,
				NULL);
			break;
		case EVENT_ROAMED:
			__cfg80211_roamed(wdev, ev->rm.bssid,
					  ev->rm.req_ie, ev->rm.req_ie_len,
					  ev->rm.resp_ie, ev->rm.resp_ie_len);
			break;
		case EVENT_DISCONNECTED:
			__cfg80211_disconnected(wdev->netdev,
						ev->dc.ie, ev->dc.ie_len,
						ev->dc.reason, true);
			break;
		case EVENT_IBSS_JOINED:
			__cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
			break;
		}
		wdev_unlock(wdev);

		kfree(ev);

		spin_lock_irqsave(&wdev->event_lock, flags);
	}
	spin_unlock_irqrestore(&wdev->event_lock, flags);
}

void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
{
	struct wireless_dev *wdev;

	ASSERT_RTNL();
	ASSERT_RDEV_LOCK(rdev);

	mutex_lock(&rdev->devlist_mtx);

	list_for_each_entry(wdev, &rdev->netdev_list, list)
		cfg80211_process_wdev_events(wdev);

	mutex_unlock(&rdev->devlist_mtx);
}

int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
			  struct net_device *dev, enum nl80211_iftype ntype,
			  u32 *flags, struct vif_params *params)
{
	int err;
	enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;

	ASSERT_RDEV_LOCK(rdev);

	/* don't support changing VLANs, you just re-create them */
	if (otype == NL80211_IFTYPE_AP_VLAN)
		return -EOPNOTSUPP;

	if (!rdev->ops->change_virtual_intf ||
	    !(rdev->wiphy.interface_modes & (1 << ntype)))
		return -EOPNOTSUPP;

	/* if it's part of a bridge, reject changing type to station/ibss */
	if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
	    (ntype == NL80211_IFTYPE_ADHOC ||
	     ntype == NL80211_IFTYPE_STATION ||
	     ntype == NL80211_IFTYPE_P2P_CLIENT))
		return -EBUSY;

	if (ntype != otype) {
		dev->ieee80211_ptr->use_4addr = false;
		dev->ieee80211_ptr->mesh_id_up_len = 0;

		switch (otype) {
		case NL80211_IFTYPE_ADHOC:
			cfg80211_leave_ibss(rdev, dev, false);
			break;
		case NL80211_IFTYPE_STATION:
		case NL80211_IFTYPE_P2P_CLIENT:
			cfg80211_disconnect(rdev, dev,
					    WLAN_REASON_DEAUTH_LEAVING, true);
			break;
		case NL80211_IFTYPE_MESH_POINT:
			/* mesh should be handled? */
			break;
		default:
			break;
		}

		cfg80211_process_rdev_events(rdev);
	}

	err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
					     ntype, flags, params);

	WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);

	if (!err && params && params->use_4addr != -1)
		dev->ieee80211_ptr->use_4addr = params->use_4addr;

	if (!err) {
		dev->priv_flags &= ~IFF_DONT_BRIDGE;
		switch (ntype) {
		case NL80211_IFTYPE_STATION:
			if (dev->ieee80211_ptr->use_4addr)
				break;
			/* fall through */
		case NL80211_IFTYPE_P2P_CLIENT:
		case NL80211_IFTYPE_ADHOC:
			dev->priv_flags |= IFF_DONT_BRIDGE;
			break;
		case NL80211_IFTYPE_P2P_GO:
		case NL80211_IFTYPE_AP:
		case NL80211_IFTYPE_AP_VLAN:
		case NL80211_IFTYPE_WDS:
		case NL80211_IFTYPE_MESH_POINT:
			/* bridging OK */
			break;
		case NL80211_IFTYPE_MONITOR:
			/* monitor can't bridge anyway */
			break;
		case NL80211_IFTYPE_UNSPECIFIED:
		case NUM_NL80211_IFTYPES:
			/* not happening */
			break;
		}
	}

	return err;
}

u16 cfg80211_calculate_bitrate(struct rate_info *rate)
{
	int modulation, streams, bitrate;

	if (!(rate->flags & RATE_INFO_FLAGS_MCS))
		return rate->legacy;

	/* the formula below does only work for MCS values smaller than 32 */
	if (rate->mcs >= 32)
		return 0;

	modulation = rate->mcs & 7;
	streams = (rate->mcs >> 3) + 1;

	bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
			13500000 : 6500000;

	if (modulation < 4)
		bitrate *= (modulation + 1);
	else if (modulation == 4)
		bitrate *= (modulation + 2);
	else
		bitrate *= (modulation + 3);

	bitrate *= streams;

	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
		bitrate = (bitrate / 9) * 10;

	/* do NOT round down here */
	return (bitrate + 50000) / 100000;
}