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