net/wireless/util.c

   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 "core.h"
  13
  14 struct ieee80211_rate *
  15 ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
  16                             u32 basic_rates, int bitrate)
  17 {
  18         struct ieee80211_rate *result = &sband->bitrates[0];
  19         int i;
  20
  21         for (i = 0; i < sband->n_bitrates; i++) {
  22                 if (!(basic_rates & BIT(i)))
  23                         continue;
  24                 if (sband->bitrates[i].bitrate > bitrate)
  25                         continue;
  26                 result = &sband->bitrates[i];
  27         }
  28
  29         return result;
  30 }
  31 EXPORT_SYMBOL(ieee80211_get_response_rate);
  32
  33 int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
  34 {
  35         /* see 802.11 17.3.8.3.2 and Annex J
  36          * there are overlapping channel numbers in 5GHz and 2GHz bands */
  37         if (band == IEEE80211_BAND_5GHZ) {
  38                 if (chan >= 182 && chan <= 196)
  39                         return 4000 + chan * 5;
  40                 else
  41                         return 5000 + chan * 5;
  42         } else { /* IEEE80211_BAND_2GHZ */
  43                 if (chan == 14)
  44                         return 2484;
  45                 else if (chan < 14)
  46                         return 2407 + chan * 5;
  47                 else
  48                         return 0; /* not supported */
  49         }
  50 }
  51 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
  52
  53 int ieee80211_frequency_to_channel(int freq)
  54 {
  55         /* see 802.11 17.3.8.3.2 and Annex J */
  56         if (freq == 2484)
  57                 return 14;
  58         else if (freq < 2484)
  59                 return (freq - 2407) / 5;
  60         else if (freq >= 4910 && freq <= 4980)
  61                 return (freq - 4000) / 5;
  62         else
  63                 return (freq - 5000) / 5;
  64 }
  65 EXPORT_SYMBOL(ieee80211_frequency_to_channel);
  66
  67 struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
  68                                                   int freq)
  69 {
  70         enum ieee80211_band band;
  71         struct ieee80211_supported_band *sband;
  72         int i;
  73
  74         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
  75                 sband = wiphy->bands[band];
  76
  77                 if (!sband)
  78                         continue;
  79
  80                 for (i = 0; i < sband->n_channels; i++) {
  81                         if (sband->channels[i].center_freq == freq)
  82                                 return &sband->channels[i];
  83                 }
  84         }
  85
  86         return NULL;
  87 }
  88 EXPORT_SYMBOL(__ieee80211_get_channel);
  89
  90 static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
  91                                      enum ieee80211_band band)
  92 {
  93         int i, want;
  94
  95         switch (band) {
  96         case IEEE80211_BAND_5GHZ:
  97                 want = 3;
  98                 for (i = 0; i < sband->n_bitrates; i++) {
  99                         if (sband->bitrates[i].bitrate == 60 ||
 100                             sband->bitrates[i].bitrate == 120 ||
 101                             sband->bitrates[i].bitrate == 240) {
 102                                 sband->bitrates[i].flags |=
 103                                         IEEE80211_RATE_MANDATORY_A;
 104                                 want--;
 105                         }
 106                 }
 107                 WARN_ON(want);
 108                 break;
 109         case IEEE80211_BAND_2GHZ:
 110                 want = 7;
 111                 for (i = 0; i < sband->n_bitrates; i++) {
 112                         if (sband->bitrates[i].bitrate == 10) {
 113                                 sband->bitrates[i].flags |=
 114                                         IEEE80211_RATE_MANDATORY_B |
 115                                         IEEE80211_RATE_MANDATORY_G;
 116                                 want--;
 117                         }
 118
 119                         if (sband->bitrates[i].bitrate == 20 ||
 120                             sband->bitrates[i].bitrate == 55 ||
 121                             sband->bitrates[i].bitrate == 110 ||
 122                             sband->bitrates[i].bitrate == 60 ||
 123                             sband->bitrates[i].bitrate == 120 ||
 124                             sband->bitrates[i].bitrate == 240) {
 125                                 sband->bitrates[i].flags |=
 126                                         IEEE80211_RATE_MANDATORY_G;
 127                                 want--;
 128                         }
 129
 130                         if (sband->bitrates[i].bitrate != 10 &&
 131                             sband->bitrates[i].bitrate != 20 &&
 132                             sband->bitrates[i].bitrate != 55 &&
 133                             sband->bitrates[i].bitrate != 110)
 134                                 sband->bitrates[i].flags |=
 135                                         IEEE80211_RATE_ERP_G;
 136                 }
 137                 WARN_ON(want != 0 && want != 3 && want != 6);
 138                 break;
 139         case IEEE80211_NUM_BANDS:
 140                 WARN_ON(1);
 141                 break;
 142         }
 143 }
 144
 145 void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
 146 {
 147         enum ieee80211_band band;
 148
 149         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 150                 if (wiphy->bands[band])
 151                         set_mandatory_flags_band(wiphy->bands[band], band);
 152 }
 153
 154 bool cfg80211_supported_cipher_suite(struct wiphy *wiphy, u32 cipher)
 155 {
 156         int i;
 157         for (i = 0; i < wiphy->n_cipher_suites; i++)
 158                 if (cipher == wiphy->cipher_suites[i])
 159                         return true;
 160         return false;
 161 }
 162
 163 int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
 164                                    struct key_params *params, int key_idx,
 165                                    bool pairwise, const u8 *mac_addr)
 166 {
 167         if (key_idx > 5)
 168                 return -EINVAL;
 169
 170         if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
 171                 return -EINVAL;
 172
 173         if (pairwise && !mac_addr)
 174                 return -EINVAL;
 175
 176         /*
 177          * Disallow pairwise keys with non-zero index unless it's WEP
 178          * or a vendor specific cipher (because current deployments use
 179          * pairwise WEP keys with non-zero indices and for vendor specific
 180          * ciphers this should be validated in the driver or hardware level
 181          * - but 802.11i clearly specifies to use zero)
 182          */
 183         if (pairwise && key_idx &&
 184             ((params->cipher == WLAN_CIPHER_SUITE_TKIP) ||
 185              (params->cipher == WLAN_CIPHER_SUITE_CCMP) ||
 186              (params->cipher == WLAN_CIPHER_SUITE_AES_CMAC)))
 187                 return -EINVAL;
 188
 189         switch (params->cipher) {
 190         case WLAN_CIPHER_SUITE_WEP40:
 191                 if (params->key_len != WLAN_KEY_LEN_WEP40)
 192                         return -EINVAL;
 193                 break;
 194         case WLAN_CIPHER_SUITE_TKIP:
 195                 if (params->key_len != WLAN_KEY_LEN_TKIP)
 196                         return -EINVAL;
 197                 break;
 198         case WLAN_CIPHER_SUITE_CCMP:
 199                 if (params->key_len != WLAN_KEY_LEN_CCMP)
 200                         return -EINVAL;
 201                 break;
 202         case WLAN_CIPHER_SUITE_WEP104:
 203                 if (params->key_len != WLAN_KEY_LEN_WEP104)
 204                         return -EINVAL;
 205                 break;
 206         case WLAN_CIPHER_SUITE_AES_CMAC:
 207                 if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
 208                         return -EINVAL;
 209                 break;
 210         default:
 211                 /*
 212                  * We don't know anything about this algorithm,
 213                  * allow using it -- but the driver must check
 214                  * all parameters! We still check below whether
 215                  * or not the driver supports this algorithm,
 216                  * of course.
 217                  */
 218                 break;
 219         }
 220
 221         if (params->seq) {
 222                 switch (params->cipher) {
 223                 case WLAN_CIPHER_SUITE_WEP40:
 224                 case WLAN_CIPHER_SUITE_WEP104:
 225                         /* These ciphers do not use key sequence */
 226                         return -EINVAL;
 227                 case WLAN_CIPHER_SUITE_TKIP:
 228                 case WLAN_CIPHER_SUITE_CCMP:
 229                 case WLAN_CIPHER_SUITE_AES_CMAC:
 230                         if (params->seq_len != 6)
 231                                 return -EINVAL;
 232                         break;
 233                 }
 234         }
 235
 236         if (!cfg80211_supported_cipher_suite(&rdev->wiphy, params->cipher))
 237                 return -EINVAL;
 238
 239         return 0;
 240 }
 241
 242 unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
 243 {
 244         unsigned int hdrlen = 24;
 245
 246         if (ieee80211_is_data(fc)) {
 247                 if (ieee80211_has_a4(fc))
 248                         hdrlen = 30;
 249                 if (ieee80211_is_data_qos(fc)) {
 250                         hdrlen += IEEE80211_QOS_CTL_LEN;
 251                         if (ieee80211_has_order(fc))
 252                                 hdrlen += IEEE80211_HT_CTL_LEN;
 253                 }
 254                 goto out;
 255         }
 256
 257         if (ieee80211_is_ctl(fc)) {
 258                 /*
 259                  * ACK and CTS are 10 bytes, all others 16. To see how
 260                  * to get this condition consider
 261                  *   subtype mask:   0b0000000011110000 (0x00F0)
 262                  *   ACK subtype:    0b0000000011010000 (0x00D0)
 263                  *   CTS subtype:    0b0000000011000000 (0x00C0)
 264                  *   bits that matter:         ^^^      (0x00E0)
 265                  *   value of those: 0b0000000011000000 (0x00C0)
 266                  */
 267                 if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
 268                         hdrlen = 10;
 269                 else
 270                         hdrlen = 16;
 271         }
 272 out:
 273         return hdrlen;
 274 }
 275 EXPORT_SYMBOL(ieee80211_hdrlen);
 276
 277 unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
 278 {
 279         const struct ieee80211_hdr *hdr =
 280                         (const struct ieee80211_hdr *)skb->data;
 281         unsigned int hdrlen;
 282
 283         if (unlikely(skb->len < 10))
 284                 return 0;
 285         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 286         if (unlikely(hdrlen > skb->len))
 287                 return 0;
 288         return hdrlen;
 289 }
 290 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
 291
 292 static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
 293 {
 294         int ae = meshhdr->flags & MESH_FLAGS_AE;
 295         /* 7.1.3.5a.2 */
 296         switch (ae) {
 297         case 0:
 298                 return 6;
 299         case MESH_FLAGS_AE_A4:
 300                 return 12;
 301         case MESH_FLAGS_AE_A5_A6:
 302                 return 18;
 303         case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
 304                 return 24;
 305         default:
 306                 return 6;
 307         }
 308 }
 309
 310 int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
 311                            enum nl80211_iftype iftype)
 312 {
 313         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 314         u16 hdrlen, ethertype;
 315         u8 *payload;
 316         u8 dst[ETH_ALEN];
 317         u8 src[ETH_ALEN] __aligned(2);
 318
 319         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
 320                 return -1;
 321
 322         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 323
 324         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
 325          * header
 326          * IEEE 802.11 address fields:
 327          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
 328          *   0     0   DA    SA    BSSID n/a
 329          *   0     1   DA    BSSID SA    n/a
 330          *   1     0   BSSID SA    DA    n/a
 331          *   1     1   RA    TA    DA    SA
 332          */
 333         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
 334         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
 335
 336         switch (hdr->frame_control &
 337                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
 338         case cpu_to_le16(IEEE80211_FCTL_TODS):
 339                 if (unlikely(iftype != NL80211_IFTYPE_AP &&
 340                              iftype != NL80211_IFTYPE_AP_VLAN &&
 341                              iftype != NL80211_IFTYPE_P2P_GO))
 342                         return -1;
 343                 break;
 344         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
 345                 if (unlikely(iftype != NL80211_IFTYPE_WDS &&
 346                              iftype != NL80211_IFTYPE_MESH_POINT &&
 347                              iftype != NL80211_IFTYPE_AP_VLAN &&
 348                              iftype != NL80211_IFTYPE_STATION))
 349                         return -1;
 350                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 351                         struct ieee80211s_hdr *meshdr =
 352                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 353                         /* make sure meshdr->flags is on the linear part */
 354                         if (!pskb_may_pull(skb, hdrlen + 1))
 355                                 return -1;
 356                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
 357                                 skb_copy_bits(skb, hdrlen +
 358                                         offsetof(struct ieee80211s_hdr, eaddr1),
 359                                         dst, ETH_ALEN);
 360                                 skb_copy_bits(skb, hdrlen +
 361                                         offsetof(struct ieee80211s_hdr, eaddr2),
 362                                         src, ETH_ALEN);
 363                         }
 364                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 365                 }
 366                 break;
 367         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
 368                 if ((iftype != NL80211_IFTYPE_STATION &&
 369                      iftype != NL80211_IFTYPE_P2P_CLIENT &&
 370                      iftype != NL80211_IFTYPE_MESH_POINT) ||
 371                     (is_multicast_ether_addr(dst) &&
 372                      !compare_ether_addr(src, addr)))
 373                         return -1;
 374                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 375                         struct ieee80211s_hdr *meshdr =
 376                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 377                         /* make sure meshdr->flags is on the linear part */
 378                         if (!pskb_may_pull(skb, hdrlen + 1))
 379                                 return -1;
 380                         if (meshdr->flags & MESH_FLAGS_AE_A4)
 381                                 skb_copy_bits(skb, hdrlen +
 382                                         offsetof(struct ieee80211s_hdr, eaddr1),
 383                                         src, ETH_ALEN);
 384                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 385                 }
 386                 break;
 387         case cpu_to_le16(0):
 388                 if (iftype != NL80211_IFTYPE_ADHOC &&
 389                     iftype != NL80211_IFTYPE_STATION)
 390                                 return -1;
 391                 break;
 392         }
 393
 394         if (!pskb_may_pull(skb, hdrlen + 8))
 395                 return -1;
 396
 397         payload = skb->data + hdrlen;
 398         ethertype = (payload[6] << 8) | payload[7];
 399
 400         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 401                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 402                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
 403                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
 404                  * replace EtherType */
 405                 skb_pull(skb, hdrlen + 6);
 406                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
 407                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
 408         } else {
 409                 struct ethhdr *ehdr;
 410                 __be16 len;
 411
 412                 skb_pull(skb, hdrlen);
 413                 len = htons(skb->len);
 414                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
 415                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
 416                 memcpy(ehdr->h_source, src, ETH_ALEN);
 417                 ehdr->h_proto = len;
 418         }
 419         return 0;
 420 }
 421 EXPORT_SYMBOL(ieee80211_data_to_8023);
 422
 423 int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
 424                              enum nl80211_iftype iftype, u8 *bssid, bool qos)
 425 {
 426         struct ieee80211_hdr hdr;
 427         u16 hdrlen, ethertype;
 428         __le16 fc;
 429         const u8 *encaps_data;
 430         int encaps_len, skip_header_bytes;
 431         int nh_pos, h_pos;
 432         int head_need;
 433
 434         if (unlikely(skb->len < ETH_HLEN))
 435                 return -EINVAL;
 436
 437         nh_pos = skb_network_header(skb) - skb->data;
 438         h_pos = skb_transport_header(skb) - skb->data;
 439
 440         /* convert Ethernet header to proper 802.11 header (based on
 441          * operation mode) */
 442         ethertype = (skb->data[12] << 8) | skb->data[13];
 443         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
 444
 445         switch (iftype) {
 446         case NL80211_IFTYPE_AP:
 447         case NL80211_IFTYPE_AP_VLAN:
 448         case NL80211_IFTYPE_P2P_GO:
 449                 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 450                 /* DA BSSID SA */
 451                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 452                 memcpy(hdr.addr2, addr, ETH_ALEN);
 453                 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
 454                 hdrlen = 24;
 455                 break;
 456         case NL80211_IFTYPE_STATION:
 457         case NL80211_IFTYPE_P2P_CLIENT:
 458                 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
 459                 /* BSSID SA DA */
 460                 memcpy(hdr.addr1, bssid, ETH_ALEN);
 461                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 462                 memcpy(hdr.addr3, skb->data, ETH_ALEN);
 463                 hdrlen = 24;
 464                 break;
 465         case NL80211_IFTYPE_ADHOC:
 466                 /* DA SA BSSID */
 467                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 468                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 469                 memcpy(hdr.addr3, bssid, ETH_ALEN);
 470                 hdrlen = 24;
 471                 break;
 472         default:
 473                 return -EOPNOTSUPP;
 474         }
 475
 476         if (qos) {
 477                 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
 478                 hdrlen += 2;
 479         }
 480
 481         hdr.frame_control = fc;
 482         hdr.duration_id = 0;
 483         hdr.seq_ctrl = 0;
 484
 485         skip_header_bytes = ETH_HLEN;
 486         if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
 487                 encaps_data = bridge_tunnel_header;
 488                 encaps_len = sizeof(bridge_tunnel_header);
 489                 skip_header_bytes -= 2;
 490         } else if (ethertype > 0x600) {
 491                 encaps_data = rfc1042_header;
 492                 encaps_len = sizeof(rfc1042_header);
 493                 skip_header_bytes -= 2;
 494         } else {
 495                 encaps_data = NULL;
 496                 encaps_len = 0;
 497         }
 498
 499         skb_pull(skb, skip_header_bytes);
 500         nh_pos -= skip_header_bytes;
 501         h_pos -= skip_header_bytes;
 502
 503         head_need = hdrlen + encaps_len - skb_headroom(skb);
 504
 505         if (head_need > 0 || skb_cloned(skb)) {
 506                 head_need = max(head_need, 0);
 507                 if (head_need)
 508                         skb_orphan(skb);
 509
 510                 if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC))
 511                         return -ENOMEM;
 512
 513                 skb->truesize += head_need;
 514         }
 515
 516         if (encaps_data) {
 517                 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
 518                 nh_pos += encaps_len;
 519                 h_pos += encaps_len;
 520         }
 521
 522         memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
 523
 524         nh_pos += hdrlen;
 525         h_pos += hdrlen;
 526
 527         /* Update skb pointers to various headers since this modified frame
 528          * is going to go through Linux networking code that may potentially
 529          * need things like pointer to IP header. */
 530         skb_set_mac_header(skb, 0);
 531         skb_set_network_header(skb, nh_pos);
 532         skb_set_transport_header(skb, h_pos);
 533
 534         return 0;
 535 }
 536 EXPORT_SYMBOL(ieee80211_data_from_8023);
 537
 538
 539 void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
 540                               const u8 *addr, enum nl80211_iftype iftype,
 541                               const unsigned int extra_headroom,
 542                               bool has_80211_header)
 543 {
 544         struct sk_buff *frame = NULL;
 545         u16 ethertype;
 546         u8 *payload;
 547         const struct ethhdr *eth;
 548         int remaining, err;
 549         u8 dst[ETH_ALEN], src[ETH_ALEN];
 550
 551         if (has_80211_header) {
 552                 err = ieee80211_data_to_8023(skb, addr, iftype);
 553                 if (err)
 554                         goto out;
 555
 556                 /* skip the wrapping header */
 557                 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
 558                 if (!eth)
 559                         goto out;
 560         } else {
 561                 eth = (struct ethhdr *) skb->data;
 562         }
 563
 564         while (skb != frame) {
 565                 u8 padding;
 566                 __be16 len = eth->h_proto;
 567                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
 568
 569                 remaining = skb->len;
 570                 memcpy(dst, eth->h_dest, ETH_ALEN);
 571                 memcpy(src, eth->h_source, ETH_ALEN);
 572
 573                 padding = (4 - subframe_len) & 0x3;
 574                 /* the last MSDU has no padding */
 575                 if (subframe_len > remaining)
 576                         goto purge;
 577
 578                 skb_pull(skb, sizeof(struct ethhdr));
 579                 /* reuse skb for the last subframe */
 580                 if (remaining <= subframe_len + padding)
 581                         frame = skb;
 582                 else {
 583                         unsigned int hlen = ALIGN(extra_headroom, 4);
 584                         /*
 585                          * Allocate and reserve two bytes more for payload
 586                          * alignment since sizeof(struct ethhdr) is 14.
 587                          */
 588                         frame = dev_alloc_skb(hlen + subframe_len + 2);
 589                         if (!frame)
 590                                 goto purge;
 591
 592                         skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
 593                         memcpy(skb_put(frame, ntohs(len)), skb->data,
 594                                 ntohs(len));
 595
 596                         eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
 597                                                         padding);
 598                         if (!eth) {
 599                                 dev_kfree_skb(frame);
 600                                 goto purge;
 601                         }
 602                 }
 603
 604                 skb_reset_network_header(frame);
 605                 frame->dev = skb->dev;
 606                 frame->priority = skb->priority;
 607
 608                 payload = frame->data;
 609                 ethertype = (payload[6] << 8) | payload[7];
 610
 611                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 612                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 613                            compare_ether_addr(payload,
 614                                               bridge_tunnel_header) == 0)) {
 615                         /* remove RFC1042 or Bridge-Tunnel
 616                          * encapsulation and replace EtherType */
 617                         skb_pull(frame, 6);
 618                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 619                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 620                 } else {
 621                         memcpy(skb_push(frame, sizeof(__be16)), &len,
 622                                 sizeof(__be16));
 623                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 624                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 625                 }
 626                 __skb_queue_tail(list, frame);
 627         }
 628
 629         return;
 630
 631  purge:
 632         __skb_queue_purge(list);
 633  out:
 634         dev_kfree_skb(skb);
 635 }
 636 EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
 637
 638 /* Given a data frame determine the 802.1p/1d tag to use. */
 639 unsigned int cfg80211_classify8021d(struct sk_buff *skb)
 640 {
 641         unsigned int dscp;
 642
 643         /* skb->priority values from 256->263 are magic values to
 644          * directly indicate a specific 802.1d priority.  This is used
 645          * to allow 802.1d priority to be passed directly in from VLAN
 646          * tags, etc.
 647          */
 648         if (skb->priority >= 256 && skb->priority <= 263)
 649                 return skb->priority - 256;
 650
 651         switch (skb->protocol) {
 652         case htons(ETH_P_IP):
 653                 dscp = ip_hdr(skb)->tos & 0xfc;
 654                 break;
 655         default:
 656                 return 0;
 657         }
 658
 659         return dscp >> 5;
 660 }
 661 EXPORT_SYMBOL(cfg80211_classify8021d);
 662
 663 const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
 664 {
 665         u8 *end, *pos;
 666
 667         pos = bss->information_elements;
 668         if (pos == NULL)
 669                 return NULL;
 670         end = pos + bss->len_information_elements;
 671
 672         while (pos + 1 < end) {
 673                 if (pos + 2 + pos[1] > end)
 674                         break;
 675                 if (pos[0] == ie)
 676                         return pos;
 677                 pos += 2 + pos[1];
 678         }
 679
 680         return NULL;
 681 }
 682 EXPORT_SYMBOL(ieee80211_bss_get_ie);
 683
 684 void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
 685 {
 686         struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
 687         struct net_device *dev = wdev->netdev;
 688         int i;
 689
 690         if (!wdev->connect_keys)
 691                 return;
 692
 693         for (i = 0; i < 6; i++) {
 694                 if (!wdev->connect_keys->params[i].cipher)
 695                         continue;
 696                 if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
 697                                         &wdev->connect_keys->params[i])) {
 698                         netdev_err(dev, "failed to set key %d\n", i);
 699                         continue;
 700                 }
 701                 if (wdev->connect_keys->def == i)
 702                         if (rdev->ops->set_default_key(wdev->wiphy, dev,
 703                                                        i, true, true)) {
 704                                 netdev_err(dev, "failed to set defkey %d\n", i);
 705                                 continue;
 706                         }
 707                 if (wdev->connect_keys->defmgmt == i)
 708                         if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
 709                                 netdev_err(dev, "failed to set mgtdef %d\n", i);
 710         }
 711
 712         kfree(wdev->connect_keys);
 713         wdev->connect_keys = NULL;
 714 }
 715
 716 static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
 717 {
 718         struct cfg80211_event *ev;
 719         unsigned long flags;
 720         const u8 *bssid = NULL;
 721
 722         spin_lock_irqsave(&wdev->event_lock, flags);
 723         while (!list_empty(&wdev->event_list)) {
 724                 ev = list_first_entry(&wdev->event_list,
 725                                       struct cfg80211_event, list);
 726                 list_del(&ev->list);
 727                 spin_unlock_irqrestore(&wdev->event_lock, flags);
 728
 729                 wdev_lock(wdev);
 730                 switch (ev->type) {
 731                 case EVENT_CONNECT_RESULT:
 732                         if (!is_zero_ether_addr(ev->cr.bssid))
 733                                 bssid = ev->cr.bssid;
 734                         __cfg80211_connect_result(
 735                                 wdev->netdev, bssid,
 736                                 ev->cr.req_ie, ev->cr.req_ie_len,
 737                                 ev->cr.resp_ie, ev->cr.resp_ie_len,
 738                                 ev->cr.status,
 739                                 ev->cr.status == WLAN_STATUS_SUCCESS,
 740                                 NULL);
 741                         break;
 742                 case EVENT_ROAMED:
 743                         __cfg80211_roamed(wdev, ev->rm.channel, ev->rm.bssid,
 744                                           ev->rm.req_ie, ev->rm.req_ie_len,
 745                                           ev->rm.resp_ie, ev->rm.resp_ie_len);
 746                         break;
 747                 case EVENT_DISCONNECTED:
 748                         __cfg80211_disconnected(wdev->netdev,
 749                                                 ev->dc.ie, ev->dc.ie_len,
 750                                                 ev->dc.reason, true);
 751                         break;
 752                 case EVENT_IBSS_JOINED:
 753                         __cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
 754                         break;
 755                 }
 756                 wdev_unlock(wdev);
 757
 758                 kfree(ev);
 759
 760                 spin_lock_irqsave(&wdev->event_lock, flags);
 761         }
 762         spin_unlock_irqrestore(&wdev->event_lock, flags);
 763 }
 764
 765 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
 766 {
 767         struct wireless_dev *wdev;
 768
 769         ASSERT_RTNL();
 770         ASSERT_RDEV_LOCK(rdev);
 771
 772         mutex_lock(&rdev->devlist_mtx);
 773
 774         list_for_each_entry(wdev, &rdev->netdev_list, list)
 775                 cfg80211_process_wdev_events(wdev);
 776
 777         mutex_unlock(&rdev->devlist_mtx);
 778 }
 779
 780 int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 781                           struct net_device *dev, enum nl80211_iftype ntype,
 782                           u32 *flags, struct vif_params *params)
 783 {
 784         int err;
 785         enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
 786
 787         ASSERT_RDEV_LOCK(rdev);
 788
 789         /* don't support changing VLANs, you just re-create them */
 790         if (otype == NL80211_IFTYPE_AP_VLAN)
 791                 return -EOPNOTSUPP;
 792
 793         if (!rdev->ops->change_virtual_intf ||
 794             !(rdev->wiphy.interface_modes & (1 << ntype)))
 795                 return -EOPNOTSUPP;
 796
 797         /* if it's part of a bridge, reject changing type to station/ibss */
 798         if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
 799             (ntype == NL80211_IFTYPE_ADHOC ||
 800              ntype == NL80211_IFTYPE_STATION ||
 801              ntype == NL80211_IFTYPE_P2P_CLIENT))
 802                 return -EBUSY;
 803
 804         if (ntype != otype) {
 805                 err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
 806                                                     ntype);
 807                 if (err)
 808                         return err;
 809
 810                 dev->ieee80211_ptr->use_4addr = false;
 811                 dev->ieee80211_ptr->mesh_id_up_len = 0;
 812
 813                 switch (otype) {
 814                 case NL80211_IFTYPE_ADHOC:
 815                         cfg80211_leave_ibss(rdev, dev, false);
 816                         break;
 817                 case NL80211_IFTYPE_STATION:
 818                 case NL80211_IFTYPE_P2P_CLIENT:
 819                         cfg80211_disconnect(rdev, dev,
 820                                             WLAN_REASON_DEAUTH_LEAVING, true);
 821                         break;
 822                 case NL80211_IFTYPE_MESH_POINT:
 823                         /* mesh should be handled? */
 824                         break;
 825                 default:
 826                         break;
 827                 }
 828
 829                 cfg80211_process_rdev_events(rdev);
 830         }
 831
 832         err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
 833                                              ntype, flags, params);
 834
 835         WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
 836
 837         if (!err && params && params->use_4addr != -1)
 838                 dev->ieee80211_ptr->use_4addr = params->use_4addr;
 839
 840         if (!err) {
 841                 dev->priv_flags &= ~IFF_DONT_BRIDGE;
 842                 switch (ntype) {
 843                 case NL80211_IFTYPE_STATION:
 844                         if (dev->ieee80211_ptr->use_4addr)
 845                                 break;
 846                         /* fall through */
 847                 case NL80211_IFTYPE_P2P_CLIENT:
 848                 case NL80211_IFTYPE_ADHOC:
 849                         dev->priv_flags |= IFF_DONT_BRIDGE;
 850                         break;
 851                 case NL80211_IFTYPE_P2P_GO:
 852                 case NL80211_IFTYPE_AP:
 853                 case NL80211_IFTYPE_AP_VLAN:
 854                 case NL80211_IFTYPE_WDS:
 855                 case NL80211_IFTYPE_MESH_POINT:
 856                         /* bridging OK */
 857                         break;
 858                 case NL80211_IFTYPE_MONITOR:
 859                         /* monitor can't bridge anyway */
 860                         break;
 861                 case NL80211_IFTYPE_UNSPECIFIED:
 862                 case NUM_NL80211_IFTYPES:
 863                         /* not happening */
 864                         break;
 865                 }
 866         }
 867
 868         return err;
 869 }
 870
 871 u16 cfg80211_calculate_bitrate(struct rate_info *rate)
 872 {
 873         int modulation, streams, bitrate;
 874
 875         if (!(rate->flags & RATE_INFO_FLAGS_MCS))
 876                 return rate->legacy;
 877
 878         /* the formula below does only work for MCS values smaller than 32 */
 879         if (rate->mcs >= 32)
 880                 return 0;
 881
 882         modulation = rate->mcs & 7;
 883         streams = (rate->mcs >> 3) + 1;
 884
 885         bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
 886                         13500000 : 6500000;
 887
 888         if (modulation < 4)
 889                 bitrate *= (modulation + 1);
 890         else if (modulation == 4)
 891                 bitrate *= (modulation + 2);
 892         else
 893                 bitrate *= (modulation + 3);
 894
 895         bitrate *= streams;
 896
 897         if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
 898                 bitrate = (bitrate / 9) * 10;
 899
 900         /* do NOT round down here */
 901         return (bitrate + 50000) / 100000;
 902 }
 903
 904 int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
 905                                  u32 beacon_int)
 906 {
 907         struct wireless_dev *wdev;
 908         int res = 0;
 909
 910         if (!beacon_int)
 911                 return -EINVAL;
 912
 913         mutex_lock(&rdev->devlist_mtx);
 914
 915         list_for_each_entry(wdev, &rdev->netdev_list, list) {
 916                 if (!wdev->beacon_interval)
 917                         continue;
 918                 if (wdev->beacon_interval != beacon_int) {
 919                         res = -EINVAL;
 920                         break;
 921                 }
 922         }
 923
 924         mutex_unlock(&rdev->devlist_mtx);
 925
 926         return res;
 927 }
 928
 929 int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
 930                                   struct wireless_dev *wdev,
 931                                   enum nl80211_iftype iftype)
 932 {
 933         struct wireless_dev *wdev_iter;
 934         int num[NUM_NL80211_IFTYPES];
 935         int total = 1;
 936         int i, j;
 937
 938         ASSERT_RTNL();
 939
 940         /* Always allow software iftypes */
 941         if (rdev->wiphy.software_iftypes & BIT(iftype))
 942                 return 0;
 943
 944         /*
 945          * Drivers will gradually all set this flag, until all
 946          * have it we only enforce for those that set it.
 947          */
 948         if (!(rdev->wiphy.flags & WIPHY_FLAG_ENFORCE_COMBINATIONS))
 949                 return 0;
 950
 951         memset(num, 0, sizeof(num));
 952
 953         num[iftype] = 1;
 954
 955         mutex_lock(&rdev->devlist_mtx);
 956         list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {
 957                 if (wdev_iter == wdev)
 958                         continue;
 959                 if (!netif_running(wdev_iter->netdev))
 960                         continue;
 961
 962                 if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))
 963                         continue;
 964
 965                 num[wdev_iter->iftype]++;
 966                 total++;
 967         }
 968         mutex_unlock(&rdev->devlist_mtx);
 969
 970         for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) {
 971                 const struct ieee80211_iface_combination *c;
 972                 struct ieee80211_iface_limit *limits;
 973
 974                 c = &rdev->wiphy.iface_combinations[i];
 975
 976                 limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
 977                                  GFP_KERNEL);
 978                 if (!limits)
 979                         return -ENOMEM;
 980                 if (total > c->max_interfaces)
 981                         goto cont;
 982
 983                 for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
 984                         if (rdev->wiphy.software_iftypes & BIT(iftype))
 985                                 continue;
 986                         for (j = 0; j < c->n_limits; j++) {
 987                                 if (!(limits[j].types & iftype))
 988                                         continue;
 989                                 if (limits[j].max < num[iftype])
 990                                         goto cont;
 991                                 limits[j].max -= num[iftype];
 992                         }
 993                 }
 994                 /* yay, it fits */
 995                 kfree(limits);
 996                 return 0;
 997  cont:
 998                 kfree(limits);
 999         }
1000
1001         return -EBUSY;
1002 }
1003
1004 int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
1005                            const u8 *rates, unsigned int n_rates,
1006                            u32 *mask)
1007 {
1008         int i, j;
1009
1010         if (!sband)
1011                 return -EINVAL;
1012
1013         if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
1014                 return -EINVAL;
1015
1016         *mask = 0;
1017
1018         for (i = 0; i < n_rates; i++) {
1019                 int rate = (rates[i] & 0x7f) * 5;
1020                 bool found = false;
1021
1022                 for (j = 0; j < sband->n_bitrates; j++) {
1023                         if (sband->bitrates[j].bitrate == rate) {
1024                                 found = true;
1025                                 *mask |= BIT(j);
1026                                 break;
1027                         }
1028                 }
1029                 if (!found)
1030                         return -EINVAL;
1031         }
1032
1033         /*
1034          * mask must have at least one bit set here since we
1035          * didn't accept a 0-length rates array nor allowed
1036          * entries in the array that didn't exist
1037          */
1038
1039         return 0;
1040 }
1041
1042 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
1043 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
1044 const unsigned char rfc1042_header[] __aligned(2) =
1045         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
1046 EXPORT_SYMBOL(rfc1042_header);
1047
1048 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
1049 const unsigned char bridge_tunnel_header[] __aligned(2) =
1050         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
1051 EXPORT_SYMBOL(bridge_tunnel_header);