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 <linux/crc32.h>
  11 #include <net/cfg80211.h>
  12 #include <net/ip.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 (band == IEEE80211_BAND_5GHZ) {
  39                 if (chan >= 182 && chan <= 196)
  40                         return 4000 + chan * 5;
  41                 else
  42                         return 5000 + chan * 5;
  43         } else { /* IEEE80211_BAND_2GHZ */
  44                 if (chan == 14)
  45                         return 2484;
  46                 else if (chan < 14)
  47                         return 2407 + chan * 5;
  48                 else
  49                         return 0; /* not supported */
  50         }
  51 }
  52 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
  53
  54 int ieee80211_frequency_to_channel(int freq)
  55 {
  56         /* see 802.11 17.3.8.3.2 and Annex J */
  57         if (freq == 2484)
  58                 return 14;
  59         else if (freq < 2484)
  60                 return (freq - 2407) / 5;
  61         else if (freq >= 4910 && freq <= 4980)
  62                 return (freq - 4000) / 5;
  63         else
  64                 return (freq - 5000) / 5;
  65 }
  66 EXPORT_SYMBOL(ieee80211_frequency_to_channel);
  67
  68 struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
  69                                                   int freq)
  70 {
  71         enum ieee80211_band band;
  72         struct ieee80211_supported_band *sband;
  73         int i;
  74
  75         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
  76                 sband = wiphy->bands[band];
  77
  78                 if (!sband)
  79                         continue;
  80
  81                 for (i = 0; i < sband->n_channels; i++) {
  82                         if (sband->channels[i].center_freq == freq)
  83                                 return &sband->channels[i];
  84                 }
  85         }
  86
  87         return NULL;
  88 }
  89 EXPORT_SYMBOL(__ieee80211_get_channel);
  90
  91 static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
  92                                      enum ieee80211_band band)
  93 {
  94         int i, want;
  95
  96         switch (band) {
  97         case IEEE80211_BAND_5GHZ:
  98                 want = 3;
  99                 for (i = 0; i < sband->n_bitrates; i++) {
 100                         if (sband->bitrates[i].bitrate == 60 ||
 101                             sband->bitrates[i].bitrate == 120 ||
 102                             sband->bitrates[i].bitrate == 240) {
 103                                 sband->bitrates[i].flags |=
 104                                         IEEE80211_RATE_MANDATORY_A;
 105                                 want--;
 106                         }
 107                 }
 108                 WARN_ON(want);
 109                 break;
 110         case IEEE80211_BAND_2GHZ:
 111                 want = 7;
 112                 for (i = 0; i < sband->n_bitrates; i++) {
 113                         if (sband->bitrates[i].bitrate == 10) {
 114                                 sband->bitrates[i].flags |=
 115                                         IEEE80211_RATE_MANDATORY_B |
 116                                         IEEE80211_RATE_MANDATORY_G;
 117                                 want--;
 118                         }
 119
 120                         if (sband->bitrates[i].bitrate == 20 ||
 121                             sband->bitrates[i].bitrate == 55 ||
 122                             sband->bitrates[i].bitrate == 110 ||
 123                             sband->bitrates[i].bitrate == 60 ||
 124                             sband->bitrates[i].bitrate == 120 ||
 125                             sband->bitrates[i].bitrate == 240) {
 126                                 sband->bitrates[i].flags |=
 127                                         IEEE80211_RATE_MANDATORY_G;
 128                                 want--;
 129                         }
 130
 131                         if (sband->bitrates[i].bitrate != 10 &&
 132                             sband->bitrates[i].bitrate != 20 &&
 133                             sband->bitrates[i].bitrate != 55 &&
 134                             sband->bitrates[i].bitrate != 110)
 135                                 sband->bitrates[i].flags |=
 136                                         IEEE80211_RATE_ERP_G;
 137                 }
 138                 WARN_ON(want != 0 && want != 3 && want != 6);
 139                 break;
 140         case IEEE80211_NUM_BANDS:
 141                 WARN_ON(1);
 142                 break;
 143         }
 144 }
 145
 146 void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
 147 {
 148         enum ieee80211_band band;
 149
 150         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 151                 if (wiphy->bands[band])
 152                         set_mandatory_flags_band(wiphy->bands[band], band);
 153 }
 154
 155 bool cfg80211_supported_cipher_suite(struct wiphy *wiphy, u32 cipher)
 156 {
 157         int i;
 158         for (i = 0; i < wiphy->n_cipher_suites; i++)
 159                 if (cipher == wiphy->cipher_suites[i])
 160                         return true;
 161         return false;
 162 }
 163
 164 int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
 165                                    struct key_params *params, int key_idx,
 166                                    bool pairwise, const u8 *mac_addr)
 167 {
 168         if (key_idx > 5)
 169                 return -EINVAL;
 170
 171         if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
 172                 return -EINVAL;
 173
 174         if (pairwise && !mac_addr)
 175                 return -EINVAL;
 176
 177         /*
 178          * Disallow pairwise keys with non-zero index unless it's WEP
 179          * or a vendor specific cipher (because current deployments use
 180          * pairwise WEP keys with non-zero indices and for vendor specific
 181          * ciphers this should be validated in the driver or hardware level
 182          * - but 802.11i clearly specifies to use zero)
 183          */
 184         if (pairwise && key_idx &&
 185             ((params->cipher == WLAN_CIPHER_SUITE_TKIP) ||
 186              (params->cipher == WLAN_CIPHER_SUITE_CCMP) ||
 187              (params->cipher == WLAN_CIPHER_SUITE_AES_CMAC)))
 188                 return -EINVAL;
 189
 190         switch (params->cipher) {
 191         case WLAN_CIPHER_SUITE_WEP40:
 192                 if (params->key_len != WLAN_KEY_LEN_WEP40)
 193                         return -EINVAL;
 194                 break;
 195         case WLAN_CIPHER_SUITE_TKIP:
 196                 if (params->key_len != WLAN_KEY_LEN_TKIP)
 197                         return -EINVAL;
 198                 break;
 199         case WLAN_CIPHER_SUITE_CCMP:
 200                 if (params->key_len != WLAN_KEY_LEN_CCMP)
 201                         return -EINVAL;
 202                 break;
 203         case WLAN_CIPHER_SUITE_WEP104:
 204                 if (params->key_len != WLAN_KEY_LEN_WEP104)
 205                         return -EINVAL;
 206                 break;
 207         case WLAN_CIPHER_SUITE_AES_CMAC:
 208                 if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
 209                         return -EINVAL;
 210                 break;
 211         default:
 212                 /*
 213                  * We don't know anything about this algorithm,
 214                  * allow using it -- but the driver must check
 215                  * all parameters! We still check below whether
 216                  * or not the driver supports this algorithm,
 217                  * of course.
 218                  */
 219                 break;
 220         }
 221
 222         if (params->seq) {
 223                 switch (params->cipher) {
 224                 case WLAN_CIPHER_SUITE_WEP40:
 225                 case WLAN_CIPHER_SUITE_WEP104:
 226                         /* These ciphers do not use key sequence */
 227                         return -EINVAL;
 228                 case WLAN_CIPHER_SUITE_TKIP:
 229                 case WLAN_CIPHER_SUITE_CCMP:
 230                 case WLAN_CIPHER_SUITE_AES_CMAC:
 231                         if (params->seq_len != 6)
 232                                 return -EINVAL;
 233                         break;
 234                 }
 235         }
 236
 237         if (!cfg80211_supported_cipher_suite(&rdev->wiphy, params->cipher))
 238                 return -EINVAL;
 239
 240         return 0;
 241 }
 242
 243 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
 244 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
 245 const unsigned char rfc1042_header[] __aligned(2) =
 246         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
 247 EXPORT_SYMBOL(rfc1042_header);
 248
 249 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
 250 const unsigned char bridge_tunnel_header[] __aligned(2) =
 251         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
 252 EXPORT_SYMBOL(bridge_tunnel_header);
 253
 254 unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
 255 {
 256         unsigned int hdrlen = 24;
 257
 258         if (ieee80211_is_data(fc)) {
 259                 if (ieee80211_has_a4(fc))
 260                         hdrlen = 30;
 261                 if (ieee80211_is_data_qos(fc)) {
 262                         hdrlen += IEEE80211_QOS_CTL_LEN;
 263                         if (ieee80211_has_order(fc))
 264                                 hdrlen += IEEE80211_HT_CTL_LEN;
 265                 }
 266                 goto out;
 267         }
 268
 269         if (ieee80211_is_ctl(fc)) {
 270                 /*
 271                  * ACK and CTS are 10 bytes, all others 16. To see how
 272                  * to get this condition consider
 273                  *   subtype mask:   0b0000000011110000 (0x00F0)
 274                  *   ACK subtype:    0b0000000011010000 (0x00D0)
 275                  *   CTS subtype:    0b0000000011000000 (0x00C0)
 276                  *   bits that matter:         ^^^      (0x00E0)
 277                  *   value of those: 0b0000000011000000 (0x00C0)
 278                  */
 279                 if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
 280                         hdrlen = 10;
 281                 else
 282                         hdrlen = 16;
 283         }
 284 out:
 285         return hdrlen;
 286 }
 287 EXPORT_SYMBOL(ieee80211_hdrlen);
 288
 289 unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
 290 {
 291         const struct ieee80211_hdr *hdr =
 292                         (const struct ieee80211_hdr *)skb->data;
 293         unsigned int hdrlen;
 294
 295         if (unlikely(skb->len < 10))
 296                 return 0;
 297         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 298         if (unlikely(hdrlen > skb->len))
 299                 return 0;
 300         return hdrlen;
 301 }
 302 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
 303
 304 static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
 305 {
 306         int ae = meshhdr->flags & MESH_FLAGS_AE;
 307         /* 7.1.3.5a.2 */
 308         switch (ae) {
 309         case 0:
 310                 return 6;
 311         case MESH_FLAGS_AE_A4:
 312                 return 12;
 313         case MESH_FLAGS_AE_A5_A6:
 314                 return 18;
 315         case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
 316                 return 24;
 317         default:
 318                 return 6;
 319         }
 320 }
 321
 322 int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
 323                            enum nl80211_iftype iftype)
 324 {
 325         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 326         u16 hdrlen, ethertype;
 327         u8 *payload;
 328         u8 dst[ETH_ALEN];
 329         u8 src[ETH_ALEN] __aligned(2);
 330
 331         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
 332                 return -1;
 333
 334         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 335
 336         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
 337          * header
 338          * IEEE 802.11 address fields:
 339          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
 340          *   0     0   DA    SA    BSSID n/a
 341          *   0     1   DA    BSSID SA    n/a
 342          *   1     0   BSSID SA    DA    n/a
 343          *   1     1   RA    TA    DA    SA
 344          */
 345         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
 346         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
 347
 348         switch (hdr->frame_control &
 349                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
 350         case cpu_to_le16(IEEE80211_FCTL_TODS):
 351                 if (unlikely(iftype != NL80211_IFTYPE_AP &&
 352                              iftype != NL80211_IFTYPE_AP_VLAN &&
 353                              iftype != NL80211_IFTYPE_P2P_GO))
 354                         return -1;
 355                 break;
 356         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
 357                 if (unlikely(iftype != NL80211_IFTYPE_WDS &&
 358                              iftype != NL80211_IFTYPE_MESH_POINT &&
 359                              iftype != NL80211_IFTYPE_AP_VLAN &&
 360                              iftype != NL80211_IFTYPE_STATION))
 361                         return -1;
 362                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 363                         struct ieee80211s_hdr *meshdr =
 364                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 365                         /* make sure meshdr->flags is on the linear part */
 366                         if (!pskb_may_pull(skb, hdrlen + 1))
 367                                 return -1;
 368                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
 369                                 skb_copy_bits(skb, hdrlen +
 370                                         offsetof(struct ieee80211s_hdr, eaddr1),
 371                                         dst, ETH_ALEN);
 372                                 skb_copy_bits(skb, hdrlen +
 373                                         offsetof(struct ieee80211s_hdr, eaddr2),
 374                                         src, ETH_ALEN);
 375                         }
 376                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 377                 }
 378                 break;
 379         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
 380                 if ((iftype != NL80211_IFTYPE_STATION &&
 381                      iftype != NL80211_IFTYPE_P2P_CLIENT &&
 382                      iftype != NL80211_IFTYPE_MESH_POINT) ||
 383                     (is_multicast_ether_addr(dst) &&
 384                      !compare_ether_addr(src, addr)))
 385                         return -1;
 386                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 387                         struct ieee80211s_hdr *meshdr =
 388                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 389                         /* make sure meshdr->flags is on the linear part */
 390                         if (!pskb_may_pull(skb, hdrlen + 1))
 391                                 return -1;
 392                         if (meshdr->flags & MESH_FLAGS_AE_A4)
 393                                 skb_copy_bits(skb, hdrlen +
 394                                         offsetof(struct ieee80211s_hdr, eaddr1),
 395                                         src, ETH_ALEN);
 396                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 397                 }
 398                 break;
 399         case cpu_to_le16(0):
 400                 if (iftype != NL80211_IFTYPE_ADHOC &&
 401                     iftype != NL80211_IFTYPE_STATION)
 402                                 return -1;
 403                 break;
 404         }
 405
 406         if (!pskb_may_pull(skb, hdrlen + 8))
 407                 return -1;
 408
 409         payload = skb->data + hdrlen;
 410         ethertype = (payload[6] << 8) | payload[7];
 411
 412         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 413                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 414                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
 415                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
 416                  * replace EtherType */
 417                 skb_pull(skb, hdrlen + 6);
 418                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
 419                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
 420         } else {
 421                 struct ethhdr *ehdr;
 422                 __be16 len;
 423
 424                 skb_pull(skb, hdrlen);
 425                 len = htons(skb->len);
 426                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
 427                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
 428                 memcpy(ehdr->h_source, src, ETH_ALEN);
 429                 ehdr->h_proto = len;
 430         }
 431         return 0;
 432 }
 433 EXPORT_SYMBOL(ieee80211_data_to_8023);
 434
 435 int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
 436                              enum nl80211_iftype iftype, u8 *bssid, bool qos)
 437 {
 438         struct ieee80211_hdr hdr;
 439         u16 hdrlen, ethertype;
 440         __le16 fc;
 441         const u8 *encaps_data;
 442         int encaps_len, skip_header_bytes;
 443         int nh_pos, h_pos;
 444         int head_need;
 445
 446         if (unlikely(skb->len < ETH_HLEN))
 447                 return -EINVAL;
 448
 449         nh_pos = skb_network_header(skb) - skb->data;
 450         h_pos = skb_transport_header(skb) - skb->data;
 451
 452         /* convert Ethernet header to proper 802.11 header (based on
 453          * operation mode) */
 454         ethertype = (skb->data[12] << 8) | skb->data[13];
 455         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
 456
 457         switch (iftype) {
 458         case NL80211_IFTYPE_AP:
 459         case NL80211_IFTYPE_AP_VLAN:
 460         case NL80211_IFTYPE_P2P_GO:
 461                 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 462                 /* DA BSSID SA */
 463                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 464                 memcpy(hdr.addr2, addr, ETH_ALEN);
 465                 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
 466                 hdrlen = 24;
 467                 break;
 468         case NL80211_IFTYPE_STATION:
 469         case NL80211_IFTYPE_P2P_CLIENT:
 470                 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
 471                 /* BSSID SA DA */
 472                 memcpy(hdr.addr1, bssid, ETH_ALEN);
 473                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 474                 memcpy(hdr.addr3, skb->data, ETH_ALEN);
 475                 hdrlen = 24;
 476                 break;
 477         case NL80211_IFTYPE_ADHOC:
 478                 /* DA SA BSSID */
 479                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 480                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 481                 memcpy(hdr.addr3, bssid, ETH_ALEN);
 482                 hdrlen = 24;
 483                 break;
 484         default:
 485                 return -EOPNOTSUPP;
 486         }
 487
 488         if (qos) {
 489                 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
 490                 hdrlen += 2;
 491         }
 492
 493         hdr.frame_control = fc;
 494         hdr.duration_id = 0;
 495         hdr.seq_ctrl = 0;
 496
 497         skip_header_bytes = ETH_HLEN;
 498         if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
 499                 encaps_data = bridge_tunnel_header;
 500                 encaps_len = sizeof(bridge_tunnel_header);
 501                 skip_header_bytes -= 2;
 502         } else if (ethertype > 0x600) {
 503                 encaps_data = rfc1042_header;
 504                 encaps_len = sizeof(rfc1042_header);
 505                 skip_header_bytes -= 2;
 506         } else {
 507                 encaps_data = NULL;
 508                 encaps_len = 0;
 509         }
 510
 511         skb_pull(skb, skip_header_bytes);
 512         nh_pos -= skip_header_bytes;
 513         h_pos -= skip_header_bytes;
 514
 515         head_need = hdrlen + encaps_len - skb_headroom(skb);
 516
 517         if (head_need > 0 || skb_cloned(skb)) {
 518                 head_need = max(head_need, 0);
 519                 if (head_need)
 520                         skb_orphan(skb);
 521
 522                 if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC))
 523                         return -ENOMEM;
 524
 525                 skb->truesize += head_need;
 526         }
 527
 528         if (encaps_data) {
 529                 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
 530                 nh_pos += encaps_len;
 531                 h_pos += encaps_len;
 532         }
 533
 534         memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
 535
 536         nh_pos += hdrlen;
 537         h_pos += hdrlen;
 538
 539         /* Update skb pointers to various headers since this modified frame
 540          * is going to go through Linux networking code that may potentially
 541          * need things like pointer to IP header. */
 542         skb_set_mac_header(skb, 0);
 543         skb_set_network_header(skb, nh_pos);
 544         skb_set_transport_header(skb, h_pos);
 545
 546         return 0;
 547 }
 548 EXPORT_SYMBOL(ieee80211_data_from_8023);
 549
 550
 551 void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
 552                               const u8 *addr, enum nl80211_iftype iftype,
 553                               const unsigned int extra_headroom,
 554                               bool has_80211_header)
 555 {
 556         struct sk_buff *frame = NULL;
 557         u16 ethertype;
 558         u8 *payload;
 559         const struct ethhdr *eth;
 560         int remaining, err;
 561         u8 dst[ETH_ALEN], src[ETH_ALEN];
 562
 563         if (has_80211_header) {
 564                 err = ieee80211_data_to_8023(skb, addr, iftype);
 565                 if (err)
 566                         goto out;
 567
 568                 /* skip the wrapping header */
 569                 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
 570                 if (!eth)
 571                         goto out;
 572         } else {
 573                 eth = (struct ethhdr *) skb->data;
 574         }
 575
 576         while (skb != frame) {
 577                 u8 padding;
 578                 __be16 len = eth->h_proto;
 579                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
 580
 581                 remaining = skb->len;
 582                 memcpy(dst, eth->h_dest, ETH_ALEN);
 583                 memcpy(src, eth->h_source, ETH_ALEN);
 584
 585                 padding = (4 - subframe_len) & 0x3;
 586                 /* the last MSDU has no padding */
 587                 if (subframe_len > remaining)
 588                         goto purge;
 589
 590                 skb_pull(skb, sizeof(struct ethhdr));
 591                 /* reuse skb for the last subframe */
 592                 if (remaining <= subframe_len + padding)
 593                         frame = skb;
 594                 else {
 595                         unsigned int hlen = ALIGN(extra_headroom, 4);
 596                         /*
 597                          * Allocate and reserve two bytes more for payload
 598                          * alignment since sizeof(struct ethhdr) is 14.
 599                          */
 600                         frame = dev_alloc_skb(hlen + subframe_len + 2);
 601                         if (!frame)
 602                                 goto purge;
 603
 604                         skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
 605                         memcpy(skb_put(frame, ntohs(len)), skb->data,
 606                                 ntohs(len));
 607
 608                         eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
 609                                                         padding);
 610                         if (!eth) {
 611                                 dev_kfree_skb(frame);
 612                                 goto purge;
 613                         }
 614                 }
 615
 616                 skb_reset_network_header(frame);
 617                 frame->dev = skb->dev;
 618                 frame->priority = skb->priority;
 619
 620                 payload = frame->data;
 621                 ethertype = (payload[6] << 8) | payload[7];
 622
 623                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 624                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 625                            compare_ether_addr(payload,
 626                                               bridge_tunnel_header) == 0)) {
 627                         /* remove RFC1042 or Bridge-Tunnel
 628                          * encapsulation and replace EtherType */
 629                         skb_pull(frame, 6);
 630                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 631                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 632                 } else {
 633                         memcpy(skb_push(frame, sizeof(__be16)), &len,
 634                                 sizeof(__be16));
 635                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 636                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 637                 }
 638                 __skb_queue_tail(list, frame);
 639         }
 640
 641         return;
 642
 643  purge:
 644         __skb_queue_purge(list);
 645  out:
 646         dev_kfree_skb(skb);
 647 }
 648 EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
 649
 650 /* Given a data frame determine the 802.1p/1d tag to use. */
 651 unsigned int cfg80211_classify8021d(struct sk_buff *skb)
 652 {
 653         unsigned int dscp;
 654
 655         /* skb->priority values from 256->263 are magic values to
 656          * directly indicate a specific 802.1d priority.  This is used
 657          * to allow 802.1d priority to be passed directly in from VLAN
 658          * tags, etc.
 659          */
 660         if (skb->priority >= 256 && skb->priority <= 263)
 661                 return skb->priority - 256;
 662
 663         switch (skb->protocol) {
 664         case htons(ETH_P_IP):
 665                 dscp = ip_hdr(skb)->tos & 0xfc;
 666                 break;
 667         default:
 668                 return 0;
 669         }
 670
 671         return dscp >> 5;
 672 }
 673 EXPORT_SYMBOL(cfg80211_classify8021d);
 674
 675 const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
 676 {
 677         u8 *end, *pos;
 678
 679         pos = bss->information_elements;
 680         if (pos == NULL)
 681                 return NULL;
 682         end = pos + bss->len_information_elements;
 683
 684         while (pos + 1 < end) {
 685                 if (pos + 2 + pos[1] > end)
 686                         break;
 687                 if (pos[0] == ie)
 688                         return pos;
 689                 pos += 2 + pos[1];
 690         }
 691
 692         return NULL;
 693 }
 694 EXPORT_SYMBOL(ieee80211_bss_get_ie);
 695
 696 void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
 697 {
 698         struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
 699         struct net_device *dev = wdev->netdev;
 700         int i;
 701
 702         if (!wdev->connect_keys)
 703                 return;
 704
 705         for (i = 0; i < 6; i++) {
 706                 if (!wdev->connect_keys->params[i].cipher)
 707                         continue;
 708                 if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
 709                                         &wdev->connect_keys->params[i])) {
 710                         netdev_err(dev, "failed to set key %d\n", i);
 711                         continue;
 712                 }
 713                 if (wdev->connect_keys->def == i)
 714                         if (rdev->ops->set_default_key(wdev->wiphy, dev,
 715                                                        i, true, true)) {
 716                                 netdev_err(dev, "failed to set defkey %d\n", i);
 717                                 continue;
 718                         }
 719                 if (wdev->connect_keys->defmgmt == i)
 720                         if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
 721                                 netdev_err(dev, "failed to set mgtdef %d\n", i);
 722         }
 723
 724         kfree(wdev->connect_keys);
 725         wdev->connect_keys = NULL;
 726 }
 727
 728 static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
 729 {
 730         struct cfg80211_event *ev;
 731         unsigned long flags;
 732         const u8 *bssid = NULL;
 733
 734         spin_lock_irqsave(&wdev->event_lock, flags);
 735         while (!list_empty(&wdev->event_list)) {
 736                 ev = list_first_entry(&wdev->event_list,
 737                                       struct cfg80211_event, list);
 738                 list_del(&ev->list);
 739                 spin_unlock_irqrestore(&wdev->event_lock, flags);
 740
 741                 wdev_lock(wdev);
 742                 switch (ev->type) {
 743                 case EVENT_CONNECT_RESULT:
 744                         if (!is_zero_ether_addr(ev->cr.bssid))
 745                                 bssid = ev->cr.bssid;
 746                         __cfg80211_connect_result(
 747                                 wdev->netdev, bssid,
 748                                 ev->cr.req_ie, ev->cr.req_ie_len,
 749                                 ev->cr.resp_ie, ev->cr.resp_ie_len,
 750                                 ev->cr.status,
 751                                 ev->cr.status == WLAN_STATUS_SUCCESS,
 752                                 NULL);
 753                         break;
 754                 case EVENT_ROAMED:
 755                         __cfg80211_roamed(wdev, ev->rm.channel, ev->rm.bssid,
 756                                           ev->rm.req_ie, ev->rm.req_ie_len,
 757                                           ev->rm.resp_ie, ev->rm.resp_ie_len);
 758                         break;
 759                 case EVENT_DISCONNECTED:
 760                         __cfg80211_disconnected(wdev->netdev,
 761                                                 ev->dc.ie, ev->dc.ie_len,
 762                                                 ev->dc.reason, true);
 763                         break;
 764                 case EVENT_IBSS_JOINED:
 765                         __cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
 766                         break;
 767                 }
 768                 wdev_unlock(wdev);
 769
 770                 kfree(ev);
 771
 772                 spin_lock_irqsave(&wdev->event_lock, flags);
 773         }
 774         spin_unlock_irqrestore(&wdev->event_lock, flags);
 775 }
 776
 777 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
 778 {
 779         struct wireless_dev *wdev;
 780
 781         ASSERT_RTNL();
 782         ASSERT_RDEV_LOCK(rdev);
 783
 784         mutex_lock(&rdev->devlist_mtx);
 785
 786         list_for_each_entry(wdev, &rdev->netdev_list, list)
 787                 cfg80211_process_wdev_events(wdev);
 788
 789         mutex_unlock(&rdev->devlist_mtx);
 790 }
 791
 792 int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 793                           struct net_device *dev, enum nl80211_iftype ntype,
 794                           u32 *flags, struct vif_params *params)
 795 {
 796         int err;
 797         enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
 798
 799         ASSERT_RDEV_LOCK(rdev);
 800
 801         /* don't support changing VLANs, you just re-create them */
 802         if (otype == NL80211_IFTYPE_AP_VLAN)
 803                 return -EOPNOTSUPP;
 804
 805         if (!rdev->ops->change_virtual_intf ||
 806             !(rdev->wiphy.interface_modes & (1 << ntype)))
 807                 return -EOPNOTSUPP;
 808
 809         /* if it's part of a bridge, reject changing type to station/ibss */
 810         if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
 811             (ntype == NL80211_IFTYPE_ADHOC ||
 812              ntype == NL80211_IFTYPE_STATION ||
 813              ntype == NL80211_IFTYPE_P2P_CLIENT))
 814                 return -EBUSY;
 815
 816         if (ntype != otype) {
 817                 err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
 818                                                     ntype);
 819                 if (err)
 820                         return err;
 821
 822                 dev->ieee80211_ptr->use_4addr = false;
 823                 dev->ieee80211_ptr->mesh_id_up_len = 0;
 824
 825                 switch (otype) {
 826                 case NL80211_IFTYPE_ADHOC:
 827                         cfg80211_leave_ibss(rdev, dev, false);
 828                         break;
 829                 case NL80211_IFTYPE_STATION:
 830                 case NL80211_IFTYPE_P2P_CLIENT:
 831                         cfg80211_disconnect(rdev, dev,
 832                                             WLAN_REASON_DEAUTH_LEAVING, true);
 833                         break;
 834                 case NL80211_IFTYPE_MESH_POINT:
 835                         /* mesh should be handled? */
 836                         break;
 837                 default:
 838                         break;
 839                 }
 840
 841                 cfg80211_process_rdev_events(rdev);
 842         }
 843
 844         err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
 845                                              ntype, flags, params);
 846
 847         WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
 848
 849         if (!err && params && params->use_4addr != -1)
 850                 dev->ieee80211_ptr->use_4addr = params->use_4addr;
 851
 852         if (!err) {
 853                 dev->priv_flags &= ~IFF_DONT_BRIDGE;
 854                 switch (ntype) {
 855                 case NL80211_IFTYPE_STATION:
 856                         if (dev->ieee80211_ptr->use_4addr)
 857                                 break;
 858                         /* fall through */
 859                 case NL80211_IFTYPE_P2P_CLIENT:
 860                 case NL80211_IFTYPE_ADHOC:
 861                         dev->priv_flags |= IFF_DONT_BRIDGE;
 862                         break;
 863                 case NL80211_IFTYPE_P2P_GO:
 864                 case NL80211_IFTYPE_AP:
 865                 case NL80211_IFTYPE_AP_VLAN:
 866                 case NL80211_IFTYPE_WDS:
 867                 case NL80211_IFTYPE_MESH_POINT:
 868                         /* bridging OK */
 869                         break;
 870                 case NL80211_IFTYPE_MONITOR:
 871                         /* monitor can't bridge anyway */
 872                         break;
 873                 case NL80211_IFTYPE_UNSPECIFIED:
 874                 case NUM_NL80211_IFTYPES:
 875                         /* not happening */
 876                         break;
 877                 }
 878         }
 879
 880         return err;
 881 }
 882
 883 u16 cfg80211_calculate_bitrate(struct rate_info *rate)
 884 {
 885         int modulation, streams, bitrate;
 886
 887         if (!(rate->flags & RATE_INFO_FLAGS_MCS))
 888                 return rate->legacy;
 889
 890         /* the formula below does only work for MCS values smaller than 32 */
 891         if (rate->mcs >= 32)
 892                 return 0;
 893
 894         modulation = rate->mcs & 7;
 895         streams = (rate->mcs >> 3) + 1;
 896
 897         bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
 898                         13500000 : 6500000;
 899
 900         if (modulation < 4)
 901                 bitrate *= (modulation + 1);
 902         else if (modulation == 4)
 903                 bitrate *= (modulation + 2);
 904         else
 905                 bitrate *= (modulation + 3);
 906
 907         bitrate *= streams;
 908
 909         if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
 910                 bitrate = (bitrate / 9) * 10;
 911
 912         /* do NOT round down here */
 913         return (bitrate + 50000) / 100000;
 914 }
 915
 916 int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
 917                                  u32 beacon_int)
 918 {
 919         struct wireless_dev *wdev;
 920         int res = 0;
 921
 922         if (!beacon_int)
 923                 return -EINVAL;
 924
 925         mutex_lock(&rdev->devlist_mtx);
 926
 927         list_for_each_entry(wdev, &rdev->netdev_list, list) {
 928                 if (!wdev->beacon_interval)
 929                         continue;
 930                 if (wdev->beacon_interval != beacon_int) {
 931                         res = -EINVAL;
 932                         break;
 933                 }
 934         }
 935
 936         mutex_unlock(&rdev->devlist_mtx);
 937
 938         return res;
 939 }
 940
 941 int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
 942                                   struct wireless_dev *wdev,
 943                                   enum nl80211_iftype iftype)
 944 {
 945         struct wireless_dev *wdev_iter;
 946         int num[NUM_NL80211_IFTYPES];
 947         int total = 1;
 948         int i, j;
 949
 950         ASSERT_RTNL();
 951
 952         /* Always allow software iftypes */
 953         if (rdev->wiphy.software_iftypes & BIT(iftype))
 954                 return 0;
 955
 956         /*
 957          * Drivers will gradually all set this flag, until all
 958          * have it we only enforce for those that set it.
 959          */
 960         if (!(rdev->wiphy.flags & WIPHY_FLAG_ENFORCE_COMBINATIONS))
 961                 return 0;
 962
 963         memset(num, 0, sizeof(num));
 964
 965         num[iftype] = 1;
 966
 967         mutex_lock(&rdev->devlist_mtx);
 968         list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {
 969                 if (wdev_iter == wdev)
 970                         continue;
 971                 if (!netif_running(wdev_iter->netdev))
 972                         continue;
 973
 974                 if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))
 975                         continue;
 976
 977                 num[wdev_iter->iftype]++;
 978                 total++;
 979         }
 980         mutex_unlock(&rdev->devlist_mtx);
 981
 982         for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) {
 983                 const struct ieee80211_iface_combination *c;
 984                 struct ieee80211_iface_limit *limits;
 985
 986                 c = &rdev->wiphy.iface_combinations[i];
 987
 988                 limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
 989                                  GFP_KERNEL);
 990                 if (!limits)
 991                         return -ENOMEM;
 992                 if (total > c->max_interfaces)
 993                         goto cont;
 994
 995                 for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
 996                         if (rdev->wiphy.software_iftypes & BIT(iftype))
 997                                 continue;
 998                         for (j = 0; j < c->n_limits; j++) {
 999                                 if (!(limits[j].types & iftype))
1000                                         continue;
1001                                 if (limits[j].max < num[iftype])
1002                                         goto cont;
1003                                 limits[j].max -= num[iftype];
1004                         }
1005                 }
1006                 /* yay, it fits */
1007                 kfree(limits);
1008                 return 0;
1009  cont:
1010                 kfree(limits);
1011         }
1012
1013         return -EBUSY;
1014 }
1015
1016 int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
1017                            const u8 *rates, unsigned int n_rates,
1018                            u32 *mask)
1019 {
1020         int i, j;
1021
1022         if (!sband)
1023                 return -EINVAL;
1024
1025         if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
1026                 return -EINVAL;
1027
1028         *mask = 0;
1029
1030         for (i = 0; i < n_rates; i++) {
1031                 int rate = (rates[i] & 0x7f) * 5;
1032                 bool found = false;
1033
1034                 for (j = 0; j < sband->n_bitrates; j++) {
1035                         if (sband->bitrates[j].bitrate == rate) {
1036                                 found = true;
1037                                 *mask |= BIT(j);
1038                                 break;
1039                         }
1040                 }
1041                 if (!found)
1042                         return -EINVAL;
1043         }
1044
1045         /*
1046          * mask must have at least one bit set here since we
1047          * didn't accept a 0-length rates array nor allowed
1048          * entries in the array that didn't exist
1049          */
1050
1051         return 0;
1052 }
1053
1054 u32 ieee802_11_parse_elems_crc(u8 *start, size_t len,
1055                                struct ieee802_11_elems *elems,
1056                                u64 filter, u32 crc)
1057 {
1058         size_t left = len;
1059         u8 *pos = start;
1060         bool calc_crc = filter != 0;
1061
1062         memset(elems, 0, sizeof(*elems));
1063         elems->ie_start = start;
1064         elems->total_len = len;
1065
1066         while (left >= 2) {
1067                 u8 id, elen;
1068
1069                 id = *pos++;
1070                 elen = *pos++;
1071                 left -= 2;
1072
1073                 if (elen > left)
1074                         break;
1075
1076                 if (calc_crc && id < 64 && (filter & (1ULL << id)))
1077                         crc = crc32_be(crc, pos - 2, elen + 2);
1078
1079                 switch (id) {
1080                 case WLAN_EID_SSID:
1081                         elems->ssid = pos;
1082                         elems->ssid_len = elen;
1083                         break;
1084                 case WLAN_EID_SUPP_RATES:
1085                         elems->supp_rates = pos;
1086                         elems->supp_rates_len = elen;
1087                         break;
1088                 case WLAN_EID_FH_PARAMS:
1089                         elems->fh_params = pos;
1090                         elems->fh_params_len = elen;
1091                         break;
1092                 case WLAN_EID_DS_PARAMS:
1093                         elems->ds_params = pos;
1094                         elems->ds_params_len = elen;
1095                         break;
1096                 case WLAN_EID_CF_PARAMS:
1097                         elems->cf_params = pos;
1098                         elems->cf_params_len = elen;
1099                         break;
1100                 case WLAN_EID_TIM:
1101                         if (elen >= sizeof(struct ieee80211_tim_ie)) {
1102                                 elems->tim = (void *)pos;
1103                                 elems->tim_len = elen;
1104                         }
1105                         break;
1106                 case WLAN_EID_IBSS_PARAMS:
1107                         elems->ibss_params = pos;
1108                         elems->ibss_params_len = elen;
1109                         break;
1110                 case WLAN_EID_CHALLENGE:
1111                         elems->challenge = pos;
1112                         elems->challenge_len = elen;
1113                         break;
1114                 case WLAN_EID_VENDOR_SPECIFIC:
1115                         if (elen >= 4 && pos[0] == 0x00 && pos[1] == 0x50 &&
1116                             pos[2] == 0xf2) {
1117                                 /* Microsoft OUI (00:50:F2) */
1118
1119                                 if (calc_crc)
1120                                         crc = crc32_be(crc, pos - 2, elen + 2);
1121
1122                                 if (pos[3] == 1) {
1123                                         /* OUI Type 1 - WPA IE */
1124                                         elems->wpa = pos;
1125                                         elems->wpa_len = elen;
1126                                 } else if (elen >= 5 && pos[3] == 2) {
1127                                         /* OUI Type 2 - WMM IE */
1128                                         if (pos[4] == 0) {
1129                                                 elems->wmm_info = pos;
1130                                                 elems->wmm_info_len = elen;
1131                                         } else if (pos[4] == 1) {
1132                                                 elems->wmm_param = pos;
1133                                                 elems->wmm_param_len = elen;
1134                                         }
1135                                 }
1136                         }
1137                         break;
1138                 case WLAN_EID_RSN:
1139                         elems->rsn = pos;
1140                         elems->rsn_len = elen;
1141                         break;
1142                 case WLAN_EID_ERP_INFO:
1143                         elems->erp_info = pos;
1144                         elems->erp_info_len = elen;
1145                         break;
1146                 case WLAN_EID_EXT_SUPP_RATES:
1147                         elems->ext_supp_rates = pos;
1148                         elems->ext_supp_rates_len = elen;
1149                         break;
1150                 case WLAN_EID_HT_CAPABILITY:
1151                         if (elen >= sizeof(struct ieee80211_ht_cap))
1152                                 elems->ht_cap_elem = (void *)pos;
1153                         break;
1154                 case WLAN_EID_HT_INFORMATION:
1155                         if (elen >= sizeof(struct ieee80211_ht_info))
1156                                 elems->ht_info_elem = (void *)pos;
1157                         break;
1158                 case WLAN_EID_MESH_ID:
1159                         elems->mesh_id = pos;
1160                         elems->mesh_id_len = elen;
1161                         break;
1162                 case WLAN_EID_MESH_CONFIG:
1163                         if (elen >= sizeof(struct ieee80211_meshconf_ie))
1164                                 elems->mesh_config = (void *)pos;
1165                         break;
1166                 case WLAN_EID_PEER_MGMT:
1167                         elems->peering = pos;
1168                         elems->peering_len = elen;
1169                         break;
1170                 case WLAN_EID_PREQ:
1171                         elems->preq = pos;
1172                         elems->preq_len = elen;
1173                         break;
1174                 case WLAN_EID_PREP:
1175                         elems->prep = pos;
1176                         elems->prep_len = elen;
1177                         break;
1178                 case WLAN_EID_PERR:
1179                         elems->perr = pos;
1180                         elems->perr_len = elen;
1181                         break;
1182                 case WLAN_EID_RANN:
1183                         if (elen >= sizeof(struct ieee80211_rann_ie))
1184                                 elems->rann = (void *)pos;
1185                         break;
1186                 case WLAN_EID_CHANNEL_SWITCH:
1187                         elems->ch_switch_elem = pos;
1188                         elems->ch_switch_elem_len = elen;
1189                         break;
1190                 case WLAN_EID_QUIET:
1191                         if (!elems->quiet_elem) {
1192                                 elems->quiet_elem = pos;
1193                                 elems->quiet_elem_len = elen;
1194                         }
1195                         elems->num_of_quiet_elem++;
1196                         break;
1197                 case WLAN_EID_COUNTRY:
1198                         elems->country_elem = pos;
1199                         elems->country_elem_len = elen;
1200                         break;
1201                 case WLAN_EID_PWR_CONSTRAINT:
1202                         elems->pwr_constr_elem = pos;
1203                         elems->pwr_constr_elem_len = elen;
1204                         break;
1205                 case WLAN_EID_TIMEOUT_INTERVAL:
1206                         elems->timeout_int = pos;
1207                         elems->timeout_int_len = elen;
1208                         break;
1209                 default:
1210                         break;
1211                 }
1212
1213                 left -= elen;
1214                 pos += elen;
1215         }
1216
1217         return crc;
1218 }
1219 EXPORT_SYMBOL(ieee802_11_parse_elems_crc);