net/wireless/util.c

   1 /*
   2  * Wireless utility functions
   3  *
   4  * Copyright 2007-2009  Johannes Berg <johannes@sipsolutions.net>
   5  */
   6 #include <linux/bitops.h>
   7 #include <linux/etherdevice.h>
   8 #include <linux/slab.h>
   9 #include <linux/crc32.h>
  10 #include <net/cfg80211.h>
  11 #include <net/ip.h>
  12 #include "core.h"
  13
  14 struct ieee80211_rate *
  15 ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
  16                             u32 basic_rates, int bitrate)
  17 {
  18         struct ieee80211_rate *result = &sband->bitrates[0];
  19         int i;
  20
  21         for (i = 0; i < sband->n_bitrates; i++) {
  22                 if (!(basic_rates & BIT(i)))
  23                         continue;
  24                 if (sband->bitrates[i].bitrate > bitrate)
  25                         continue;
  26                 result = &sband->bitrates[i];
  27         }
  28
  29         return result;
  30 }
  31 EXPORT_SYMBOL(ieee80211_get_response_rate);
  32
  33 int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
  34 {
  35         /* see 802.11 17.3.8.3.2 and Annex J
  36          * there are overlapping channel numbers in 5GHz and 2GHz bands */
  37         if (band == IEEE80211_BAND_5GHZ) {
  38                 if (chan >= 182 && chan <= 196)
  39                         return 4000 + chan * 5;
  40                 else
  41                         return 5000 + chan * 5;
  42         } else { /* IEEE80211_BAND_2GHZ */
  43                 if (chan == 14)
  44                         return 2484;
  45                 else if (chan < 14)
  46                         return 2407 + chan * 5;
  47                 else
  48                         return 0; /* not supported */
  49         }
  50 }
  51 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
  52
  53 int ieee80211_frequency_to_channel(int freq)
  54 {
  55         /* see 802.11 17.3.8.3.2 and Annex J */
  56         if (freq == 2484)
  57                 return 14;
  58         else if (freq < 2484)
  59                 return (freq - 2407) / 5;
  60         else if (freq >= 4910 && freq <= 4980)
  61                 return (freq - 4000) / 5;
  62         else
  63                 return (freq - 5000) / 5;
  64 }
  65 EXPORT_SYMBOL(ieee80211_frequency_to_channel);
  66
  67 struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
  68                                                   int freq)
  69 {
  70         enum ieee80211_band band;
  71         struct ieee80211_supported_band *sband;
  72         int i;
  73
  74         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
  75                 sband = wiphy->bands[band];
  76
  77                 if (!sband)
  78                         continue;
  79
  80                 for (i = 0; i < sband->n_channels; i++) {
  81                         if (sband->channels[i].center_freq == freq)
  82                                 return &sband->channels[i];
  83                 }
  84         }
  85
  86         return NULL;
  87 }
  88 EXPORT_SYMBOL(__ieee80211_get_channel);
  89
  90 static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
  91                                      enum ieee80211_band band)
  92 {
  93         int i, want;
  94
  95         switch (band) {
  96         case IEEE80211_BAND_5GHZ:
  97                 want = 3;
  98                 for (i = 0; i < sband->n_bitrates; i++) {
  99                         if (sband->bitrates[i].bitrate == 60 ||
 100                             sband->bitrates[i].bitrate == 120 ||
 101                             sband->bitrates[i].bitrate == 240) {
 102                                 sband->bitrates[i].flags |=
 103                                         IEEE80211_RATE_MANDATORY_A;
 104                                 want--;
 105                         }
 106                 }
 107                 WARN_ON(want);
 108                 break;
 109         case IEEE80211_BAND_2GHZ:
 110                 want = 7;
 111                 for (i = 0; i < sband->n_bitrates; i++) {
 112                         if (sband->bitrates[i].bitrate == 10) {
 113                                 sband->bitrates[i].flags |=
 114                                         IEEE80211_RATE_MANDATORY_B |
 115                                         IEEE80211_RATE_MANDATORY_G;
 116                                 want--;
 117                         }
 118
 119                         if (sband->bitrates[i].bitrate == 20 ||
 120                             sband->bitrates[i].bitrate == 55 ||
 121                             sband->bitrates[i].bitrate == 110 ||
 122                             sband->bitrates[i].bitrate == 60 ||
 123                             sband->bitrates[i].bitrate == 120 ||
 124                             sband->bitrates[i].bitrate == 240) {
 125                                 sband->bitrates[i].flags |=
 126                                         IEEE80211_RATE_MANDATORY_G;
 127                                 want--;
 128                         }
 129
 130                         if (sband->bitrates[i].bitrate != 10 &&
 131                             sband->bitrates[i].bitrate != 20 &&
 132                             sband->bitrates[i].bitrate != 55 &&
 133                             sband->bitrates[i].bitrate != 110)
 134                                 sband->bitrates[i].flags |=
 135                                         IEEE80211_RATE_ERP_G;
 136                 }
 137                 WARN_ON(want != 0 && want != 3 && want != 6);
 138                 break;
 139         case IEEE80211_NUM_BANDS:
 140                 WARN_ON(1);
 141                 break;
 142         }
 143 }
 144
 145 void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
 146 {
 147         enum ieee80211_band band;
 148
 149         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 150                 if (wiphy->bands[band])
 151                         set_mandatory_flags_band(wiphy->bands[band], band);
 152 }
 153
 154 bool cfg80211_supported_cipher_suite(struct wiphy *wiphy, u32 cipher)
 155 {
 156         int i;
 157         for (i = 0; i < wiphy->n_cipher_suites; i++)
 158                 if (cipher == wiphy->cipher_suites[i])
 159                         return true;
 160         return false;
 161 }
 162
 163 int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
 164                                    struct key_params *params, int key_idx,
 165                                    bool pairwise, const u8 *mac_addr)
 166 {
 167         if (key_idx > 5)
 168                 return -EINVAL;
 169
 170         if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
 171                 return -EINVAL;
 172
 173         if (pairwise && !mac_addr)
 174                 return -EINVAL;
 175
 176         /*
 177          * Disallow pairwise keys with non-zero index unless it's WEP
 178          * or a vendor specific cipher (because current deployments use
 179          * pairwise WEP keys with non-zero indices and for vendor specific
 180          * ciphers this should be validated in the driver or hardware level
 181          * - but 802.11i clearly specifies to use zero)
 182          */
 183         if (pairwise && key_idx &&
 184             ((params->cipher == WLAN_CIPHER_SUITE_TKIP) ||
 185              (params->cipher == WLAN_CIPHER_SUITE_CCMP) ||
 186              (params->cipher == WLAN_CIPHER_SUITE_AES_CMAC)))
 187                 return -EINVAL;
 188
 189         switch (params->cipher) {
 190         case WLAN_CIPHER_SUITE_WEP40:
 191                 if (params->key_len != WLAN_KEY_LEN_WEP40)
 192                         return -EINVAL;
 193                 break;
 194         case WLAN_CIPHER_SUITE_TKIP:
 195                 if (params->key_len != WLAN_KEY_LEN_TKIP)
 196                         return -EINVAL;
 197                 break;
 198         case WLAN_CIPHER_SUITE_CCMP:
 199                 if (params->key_len != WLAN_KEY_LEN_CCMP)
 200                         return -EINVAL;
 201                 break;
 202         case WLAN_CIPHER_SUITE_WEP104:
 203                 if (params->key_len != WLAN_KEY_LEN_WEP104)
 204                         return -EINVAL;
 205                 break;
 206         case WLAN_CIPHER_SUITE_AES_CMAC:
 207                 if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
 208                         return -EINVAL;
 209                 break;
 210         default:
 211                 /*
 212                  * We don't know anything about this algorithm,
 213                  * allow using it -- but the driver must check
 214                  * all parameters! We still check below whether
 215                  * or not the driver supports this algorithm,
 216                  * of course.
 217                  */
 218                 break;
 219         }
 220
 221         if (params->seq) {
 222                 switch (params->cipher) {
 223                 case WLAN_CIPHER_SUITE_WEP40:
 224                 case WLAN_CIPHER_SUITE_WEP104:
 225                         /* These ciphers do not use key sequence */
 226                         return -EINVAL;
 227                 case WLAN_CIPHER_SUITE_TKIP:
 228                 case WLAN_CIPHER_SUITE_CCMP:
 229                 case WLAN_CIPHER_SUITE_AES_CMAC:
 230                         if (params->seq_len != 6)
 231                                 return -EINVAL;
 232                         break;
 233                 }
 234         }
 235
 236         if (!cfg80211_supported_cipher_suite(&rdev->wiphy, params->cipher))
 237                 return -EINVAL;
 238
 239         return 0;
 240 }
 241
 242 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
 243 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
 244 const unsigned char rfc1042_header[] __aligned(2) =
 245         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
 246 EXPORT_SYMBOL(rfc1042_header);
 247
 248 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
 249 const unsigned char bridge_tunnel_header[] __aligned(2) =
 250         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
 251 EXPORT_SYMBOL(bridge_tunnel_header);
 252
 253 unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
 254 {
 255         unsigned int hdrlen = 24;
 256
 257         if (ieee80211_is_data(fc)) {
 258                 if (ieee80211_has_a4(fc))
 259                         hdrlen = 30;
 260                 if (ieee80211_is_data_qos(fc)) {
 261                         hdrlen += IEEE80211_QOS_CTL_LEN;
 262                         if (ieee80211_has_order(fc))
 263                                 hdrlen += IEEE80211_HT_CTL_LEN;
 264                 }
 265                 goto out;
 266         }
 267
 268         if (ieee80211_is_ctl(fc)) {
 269                 /*
 270                  * ACK and CTS are 10 bytes, all others 16. To see how
 271                  * to get this condition consider
 272                  *   subtype mask:   0b0000000011110000 (0x00F0)
 273                  *   ACK subtype:    0b0000000011010000 (0x00D0)
 274                  *   CTS subtype:    0b0000000011000000 (0x00C0)
 275                  *   bits that matter:         ^^^      (0x00E0)
 276                  *   value of those: 0b0000000011000000 (0x00C0)
 277                  */
 278                 if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
 279                         hdrlen = 10;
 280                 else
 281                         hdrlen = 16;
 282         }
 283 out:
 284         return hdrlen;
 285 }
 286 EXPORT_SYMBOL(ieee80211_hdrlen);
 287
 288 unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
 289 {
 290         const struct ieee80211_hdr *hdr =
 291                         (const struct ieee80211_hdr *)skb->data;
 292         unsigned int hdrlen;
 293
 294         if (unlikely(skb->len < 10))
 295                 return 0;
 296         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 297         if (unlikely(hdrlen > skb->len))
 298                 return 0;
 299         return hdrlen;
 300 }
 301 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
 302
 303 static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
 304 {
 305         int ae = meshhdr->flags & MESH_FLAGS_AE;
 306         /* 7.1.3.5a.2 */
 307         switch (ae) {
 308         case 0:
 309                 return 6;
 310         case MESH_FLAGS_AE_A4:
 311                 return 12;
 312         case MESH_FLAGS_AE_A5_A6:
 313                 return 18;
 314         case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
 315                 return 24;
 316         default:
 317                 return 6;
 318         }
 319 }
 320
 321 int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
 322                            enum nl80211_iftype iftype)
 323 {
 324         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 325         u16 hdrlen, ethertype;
 326         u8 *payload;
 327         u8 dst[ETH_ALEN];
 328         u8 src[ETH_ALEN] __aligned(2);
 329
 330         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
 331                 return -1;
 332
 333         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 334
 335         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
 336          * header
 337          * IEEE 802.11 address fields:
 338          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
 339          *   0     0   DA    SA    BSSID n/a
 340          *   0     1   DA    BSSID SA    n/a
 341          *   1     0   BSSID SA    DA    n/a
 342          *   1     1   RA    TA    DA    SA
 343          */
 344         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
 345         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
 346
 347         switch (hdr->frame_control &
 348                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
 349         case cpu_to_le16(IEEE80211_FCTL_TODS):
 350                 if (unlikely(iftype != NL80211_IFTYPE_AP &&
 351                              iftype != NL80211_IFTYPE_AP_VLAN &&
 352                              iftype != NL80211_IFTYPE_P2P_GO))
 353                         return -1;
 354                 break;
 355         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
 356                 if (unlikely(iftype != NL80211_IFTYPE_WDS &&
 357                              iftype != NL80211_IFTYPE_MESH_POINT &&
 358                              iftype != NL80211_IFTYPE_AP_VLAN &&
 359                              iftype != NL80211_IFTYPE_STATION))
 360                         return -1;
 361                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 362                         struct ieee80211s_hdr *meshdr =
 363                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 364                         /* make sure meshdr->flags is on the linear part */
 365                         if (!pskb_may_pull(skb, hdrlen + 1))
 366                                 return -1;
 367                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
 368                                 skb_copy_bits(skb, hdrlen +
 369                                         offsetof(struct ieee80211s_hdr, eaddr1),
 370                                         dst, ETH_ALEN);
 371                                 skb_copy_bits(skb, hdrlen +
 372                                         offsetof(struct ieee80211s_hdr, eaddr2),
 373                                         src, ETH_ALEN);
 374                         }
 375                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 376                 }
 377                 break;
 378         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
 379                 if ((iftype != NL80211_IFTYPE_STATION &&
 380                      iftype != NL80211_IFTYPE_P2P_CLIENT &&
 381                      iftype != NL80211_IFTYPE_MESH_POINT) ||
 382                     (is_multicast_ether_addr(dst) &&
 383                      !compare_ether_addr(src, addr)))
 384                         return -1;
 385                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 386                         struct ieee80211s_hdr *meshdr =
 387                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 388                         /* make sure meshdr->flags is on the linear part */
 389                         if (!pskb_may_pull(skb, hdrlen + 1))
 390                                 return -1;
 391                         if (meshdr->flags & MESH_FLAGS_AE_A4)
 392                                 skb_copy_bits(skb, hdrlen +
 393                                         offsetof(struct ieee80211s_hdr, eaddr1),
 394                                         src, ETH_ALEN);
 395                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 396                 }
 397                 break;
 398         case cpu_to_le16(0):
 399                 if (iftype != NL80211_IFTYPE_ADHOC)
 400                         return -1;
 401                 break;
 402         }
 403
 404         if (!pskb_may_pull(skb, hdrlen + 8))
 405                 return -1;
 406
 407         payload = skb->data + hdrlen;
 408         ethertype = (payload[6] << 8) | payload[7];
 409
 410         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 411                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 412                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
 413                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
 414                  * replace EtherType */
 415                 skb_pull(skb, hdrlen + 6);
 416                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
 417                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
 418         } else {
 419                 struct ethhdr *ehdr;
 420                 __be16 len;
 421
 422                 skb_pull(skb, hdrlen);
 423                 len = htons(skb->len);
 424                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
 425                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
 426                 memcpy(ehdr->h_source, src, ETH_ALEN);
 427                 ehdr->h_proto = len;
 428         }
 429         return 0;
 430 }
 431 EXPORT_SYMBOL(ieee80211_data_to_8023);
 432
 433 int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
 434                              enum nl80211_iftype iftype, u8 *bssid, bool qos)
 435 {
 436         struct ieee80211_hdr hdr;
 437         u16 hdrlen, ethertype;
 438         __le16 fc;
 439         const u8 *encaps_data;
 440         int encaps_len, skip_header_bytes;
 441         int nh_pos, h_pos;
 442         int head_need;
 443
 444         if (unlikely(skb->len < ETH_HLEN))
 445                 return -EINVAL;
 446
 447         nh_pos = skb_network_header(skb) - skb->data;
 448         h_pos = skb_transport_header(skb) - skb->data;
 449
 450         /* convert Ethernet header to proper 802.11 header (based on
 451          * operation mode) */
 452         ethertype = (skb->data[12] << 8) | skb->data[13];
 453         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
 454
 455         switch (iftype) {
 456         case NL80211_IFTYPE_AP:
 457         case NL80211_IFTYPE_AP_VLAN:
 458         case NL80211_IFTYPE_P2P_GO:
 459                 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 460                 /* DA BSSID SA */
 461                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 462                 memcpy(hdr.addr2, addr, ETH_ALEN);
 463                 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
 464                 hdrlen = 24;
 465                 break;
 466         case NL80211_IFTYPE_STATION:
 467         case NL80211_IFTYPE_P2P_CLIENT:
 468                 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
 469                 /* BSSID SA DA */
 470                 memcpy(hdr.addr1, bssid, ETH_ALEN);
 471                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 472                 memcpy(hdr.addr3, skb->data, ETH_ALEN);
 473                 hdrlen = 24;
 474                 break;
 475         case NL80211_IFTYPE_ADHOC:
 476                 /* DA SA BSSID */
 477                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 478                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 479                 memcpy(hdr.addr3, bssid, ETH_ALEN);
 480                 hdrlen = 24;
 481                 break;
 482         default:
 483                 return -EOPNOTSUPP;
 484         }
 485
 486         if (qos) {
 487                 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
 488                 hdrlen += 2;
 489         }
 490
 491         hdr.frame_control = fc;
 492         hdr.duration_id = 0;
 493         hdr.seq_ctrl = 0;
 494
 495         skip_header_bytes = ETH_HLEN;
 496         if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
 497                 encaps_data = bridge_tunnel_header;
 498                 encaps_len = sizeof(bridge_tunnel_header);
 499                 skip_header_bytes -= 2;
 500         } else if (ethertype > 0x600) {
 501                 encaps_data = rfc1042_header;
 502                 encaps_len = sizeof(rfc1042_header);
 503                 skip_header_bytes -= 2;
 504         } else {
 505                 encaps_data = NULL;
 506                 encaps_len = 0;
 507         }
 508
 509         skb_pull(skb, skip_header_bytes);
 510         nh_pos -= skip_header_bytes;
 511         h_pos -= skip_header_bytes;
 512
 513         head_need = hdrlen + encaps_len - skb_headroom(skb);
 514
 515         if (head_need > 0 || skb_cloned(skb)) {
 516                 head_need = max(head_need, 0);
 517                 if (head_need)
 518                         skb_orphan(skb);
 519
 520                 if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC))
 521                         return -ENOMEM;
 522
 523                 skb->truesize += head_need;
 524         }
 525
 526         if (encaps_data) {
 527                 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
 528                 nh_pos += encaps_len;
 529                 h_pos += encaps_len;
 530         }
 531
 532         memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
 533
 534         nh_pos += hdrlen;
 535         h_pos += hdrlen;
 536
 537         /* Update skb pointers to various headers since this modified frame
 538          * is going to go through Linux networking code that may potentially
 539          * need things like pointer to IP header. */
 540         skb_set_mac_header(skb, 0);
 541         skb_set_network_header(skb, nh_pos);
 542         skb_set_transport_header(skb, h_pos);
 543
 544         return 0;
 545 }
 546 EXPORT_SYMBOL(ieee80211_data_from_8023);
 547
 548
 549 void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
 550                               const u8 *addr, enum nl80211_iftype iftype,
 551                               const unsigned int extra_headroom,
 552                               bool has_80211_header)
 553 {
 554         struct sk_buff *frame = NULL;
 555         u16 ethertype;
 556         u8 *payload;
 557         const struct ethhdr *eth;
 558         int remaining, err;
 559         u8 dst[ETH_ALEN], src[ETH_ALEN];
 560
 561         if (has_80211_header) {
 562                 err = ieee80211_data_to_8023(skb, addr, iftype);
 563                 if (err)
 564                         goto out;
 565
 566                 /* skip the wrapping header */
 567                 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
 568                 if (!eth)
 569                         goto out;
 570         } else {
 571                 eth = (struct ethhdr *) skb->data;
 572         }
 573
 574         while (skb != frame) {
 575                 u8 padding;
 576                 __be16 len = eth->h_proto;
 577                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
 578
 579                 remaining = skb->len;
 580                 memcpy(dst, eth->h_dest, ETH_ALEN);
 581                 memcpy(src, eth->h_source, ETH_ALEN);
 582
 583                 padding = (4 - subframe_len) & 0x3;
 584                 /* the last MSDU has no padding */
 585                 if (subframe_len > remaining)
 586                         goto purge;
 587
 588                 skb_pull(skb, sizeof(struct ethhdr));
 589                 /* reuse skb for the last subframe */
 590                 if (remaining <= subframe_len + padding)
 591                         frame = skb;
 592                 else {
 593                         unsigned int hlen = ALIGN(extra_headroom, 4);
 594                         /*
 595                          * Allocate and reserve two bytes more for payload
 596                          * alignment since sizeof(struct ethhdr) is 14.
 597                          */
 598                         frame = dev_alloc_skb(hlen + subframe_len + 2);
 599                         if (!frame)
 600                                 goto purge;
 601
 602                         skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
 603                         memcpy(skb_put(frame, ntohs(len)), skb->data,
 604                                 ntohs(len));
 605
 606                         eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
 607                                                         padding);
 608                         if (!eth) {
 609                                 dev_kfree_skb(frame);
 610                                 goto purge;
 611                         }
 612                 }
 613
 614                 skb_reset_network_header(frame);
 615                 frame->dev = skb->dev;
 616                 frame->priority = skb->priority;
 617
 618                 payload = frame->data;
 619                 ethertype = (payload[6] << 8) | payload[7];
 620
 621                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 622                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 623                            compare_ether_addr(payload,
 624                                               bridge_tunnel_header) == 0)) {
 625                         /* remove RFC1042 or Bridge-Tunnel
 626                          * encapsulation and replace EtherType */
 627                         skb_pull(frame, 6);
 628                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 629                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 630                 } else {
 631                         memcpy(skb_push(frame, sizeof(__be16)), &len,
 632                                 sizeof(__be16));
 633                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 634                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 635                 }
 636                 __skb_queue_tail(list, frame);
 637         }
 638
 639         return;
 640
 641  purge:
 642         __skb_queue_purge(list);
 643  out:
 644         dev_kfree_skb(skb);
 645 }
 646 EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
 647
 648 /* Given a data frame determine the 802.1p/1d tag to use. */
 649 unsigned int cfg80211_classify8021d(struct sk_buff *skb)
 650 {
 651         unsigned int dscp;
 652
 653         /* skb->priority values from 256->263 are magic values to
 654          * directly indicate a specific 802.1d priority.  This is used
 655          * to allow 802.1d priority to be passed directly in from VLAN
 656          * tags, etc.
 657          */
 658         if (skb->priority >= 256 && skb->priority <= 263)
 659                 return skb->priority - 256;
 660
 661         switch (skb->protocol) {
 662         case htons(ETH_P_IP):
 663                 dscp = ip_hdr(skb)->tos & 0xfc;
 664                 break;
 665         default:
 666                 return 0;
 667         }
 668
 669         return dscp >> 5;
 670 }
 671 EXPORT_SYMBOL(cfg80211_classify8021d);
 672
 673 const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
 674 {
 675         u8 *end, *pos;
 676
 677         pos = bss->information_elements;
 678         if (pos == NULL)
 679                 return NULL;
 680         end = pos + bss->len_information_elements;
 681
 682         while (pos + 1 < end) {
 683                 if (pos + 2 + pos[1] > end)
 684                         break;
 685                 if (pos[0] == ie)
 686                         return pos;
 687                 pos += 2 + pos[1];
 688         }
 689
 690         return NULL;
 691 }
 692 EXPORT_SYMBOL(ieee80211_bss_get_ie);
 693
 694 void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
 695 {
 696         struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
 697         struct net_device *dev = wdev->netdev;
 698         int i;
 699
 700         if (!wdev->connect_keys)
 701                 return;
 702
 703         for (i = 0; i < 6; i++) {
 704                 if (!wdev->connect_keys->params[i].cipher)
 705                         continue;
 706                 if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
 707                                         &wdev->connect_keys->params[i])) {
 708                         netdev_err(dev, "failed to set key %d\n", i);
 709                         continue;
 710                 }
 711                 if (wdev->connect_keys->def == i)
 712                         if (rdev->ops->set_default_key(wdev->wiphy, dev,
 713                                                        i, true, true)) {
 714                                 netdev_err(dev, "failed to set defkey %d\n", i);
 715                                 continue;
 716                         }
 717                 if (wdev->connect_keys->defmgmt == i)
 718                         if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
 719                                 netdev_err(dev, "failed to set mgtdef %d\n", i);
 720         }
 721
 722         kfree(wdev->connect_keys);
 723         wdev->connect_keys = NULL;
 724 }
 725
 726 static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
 727 {
 728         struct cfg80211_event *ev;
 729         unsigned long flags;
 730         const u8 *bssid = NULL;
 731
 732         spin_lock_irqsave(&wdev->event_lock, flags);
 733         while (!list_empty(&wdev->event_list)) {
 734                 ev = list_first_entry(&wdev->event_list,
 735                                       struct cfg80211_event, list);
 736                 list_del(&ev->list);
 737                 spin_unlock_irqrestore(&wdev->event_lock, flags);
 738
 739                 wdev_lock(wdev);
 740                 switch (ev->type) {
 741                 case EVENT_CONNECT_RESULT:
 742                         if (!is_zero_ether_addr(ev->cr.bssid))
 743                                 bssid = ev->cr.bssid;
 744                         __cfg80211_connect_result(
 745                                 wdev->netdev, bssid,
 746                                 ev->cr.req_ie, ev->cr.req_ie_len,
 747                                 ev->cr.resp_ie, ev->cr.resp_ie_len,
 748                                 ev->cr.status,
 749                                 ev->cr.status == WLAN_STATUS_SUCCESS,
 750                                 NULL);
 751                         break;
 752                 case EVENT_ROAMED:
 753                         __cfg80211_roamed(wdev, ev->rm.channel, ev->rm.bssid,
 754                                           ev->rm.req_ie, ev->rm.req_ie_len,
 755                                           ev->rm.resp_ie, ev->rm.resp_ie_len);
 756                         break;
 757                 case EVENT_DISCONNECTED:
 758                         __cfg80211_disconnected(wdev->netdev,
 759                                                 ev->dc.ie, ev->dc.ie_len,
 760                                                 ev->dc.reason, true);
 761                         break;
 762                 case EVENT_IBSS_JOINED:
 763                         __cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
 764                         break;
 765                 }
 766                 wdev_unlock(wdev);
 767
 768                 kfree(ev);
 769
 770                 spin_lock_irqsave(&wdev->event_lock, flags);
 771         }
 772         spin_unlock_irqrestore(&wdev->event_lock, flags);
 773 }
 774
 775 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
 776 {
 777         struct wireless_dev *wdev;
 778
 779         ASSERT_RTNL();
 780         ASSERT_RDEV_LOCK(rdev);
 781
 782         mutex_lock(&rdev->devlist_mtx);
 783
 784         list_for_each_entry(wdev, &rdev->netdev_list, list)
 785                 cfg80211_process_wdev_events(wdev);
 786
 787         mutex_unlock(&rdev->devlist_mtx);
 788 }
 789
 790 int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 791                           struct net_device *dev, enum nl80211_iftype ntype,
 792                           u32 *flags, struct vif_params *params)
 793 {
 794         int err;
 795         enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
 796
 797         ASSERT_RDEV_LOCK(rdev);
 798
 799         /* don't support changing VLANs, you just re-create them */
 800         if (otype == NL80211_IFTYPE_AP_VLAN)
 801                 return -EOPNOTSUPP;
 802
 803         if (!rdev->ops->change_virtual_intf ||
 804             !(rdev->wiphy.interface_modes & (1 << ntype)))
 805                 return -EOPNOTSUPP;
 806
 807         /* if it's part of a bridge, reject changing type to station/ibss */
 808         if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
 809             (ntype == NL80211_IFTYPE_ADHOC ||
 810              ntype == NL80211_IFTYPE_STATION ||
 811              ntype == NL80211_IFTYPE_P2P_CLIENT))
 812                 return -EBUSY;
 813
 814         if (ntype != otype) {
 815                 err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
 816                                                     ntype);
 817                 if (err)
 818                         return err;
 819
 820                 dev->ieee80211_ptr->use_4addr = false;
 821                 dev->ieee80211_ptr->mesh_id_up_len = 0;
 822
 823                 switch (otype) {
 824                 case NL80211_IFTYPE_ADHOC:
 825                         cfg80211_leave_ibss(rdev, dev, false);
 826                         break;
 827                 case NL80211_IFTYPE_STATION:
 828                 case NL80211_IFTYPE_P2P_CLIENT:
 829                         cfg80211_disconnect(rdev, dev,
 830                                             WLAN_REASON_DEAUTH_LEAVING, true);
 831                         break;
 832                 case NL80211_IFTYPE_MESH_POINT:
 833                         /* mesh should be handled? */
 834                         break;
 835                 default:
 836                         break;
 837                 }
 838
 839                 cfg80211_process_rdev_events(rdev);
 840         }
 841
 842         err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
 843                                              ntype, flags, params);
 844
 845         WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
 846
 847         if (!err && params && params->use_4addr != -1)
 848                 dev->ieee80211_ptr->use_4addr = params->use_4addr;
 849
 850         if (!err) {
 851                 dev->priv_flags &= ~IFF_DONT_BRIDGE;
 852                 switch (ntype) {
 853                 case NL80211_IFTYPE_STATION:
 854                         if (dev->ieee80211_ptr->use_4addr)
 855                                 break;
 856                         /* fall through */
 857                 case NL80211_IFTYPE_P2P_CLIENT:
 858                 case NL80211_IFTYPE_ADHOC:
 859                         dev->priv_flags |= IFF_DONT_BRIDGE;
 860                         break;
 861                 case NL80211_IFTYPE_P2P_GO:
 862                 case NL80211_IFTYPE_AP:
 863                 case NL80211_IFTYPE_AP_VLAN:
 864                 case NL80211_IFTYPE_WDS:
 865                 case NL80211_IFTYPE_MESH_POINT:
 866                         /* bridging OK */
 867                         break;
 868                 case NL80211_IFTYPE_MONITOR:
 869                         /* monitor can't bridge anyway */
 870                         break;
 871                 case NL80211_IFTYPE_UNSPECIFIED:
 872                 case NUM_NL80211_IFTYPES:
 873                         /* not happening */
 874                         break;
 875                 }
 876         }
 877
 878         return err;
 879 }
 880
 881 u16 cfg80211_calculate_bitrate(struct rate_info *rate)
 882 {
 883         int modulation, streams, bitrate;
 884
 885         if (!(rate->flags & RATE_INFO_FLAGS_MCS))
 886                 return rate->legacy;
 887
 888         /* the formula below does only work for MCS values smaller than 32 */
 889         if (rate->mcs >= 32)
 890                 return 0;
 891
 892         modulation = rate->mcs & 7;
 893         streams = (rate->mcs >> 3) + 1;
 894
 895         bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
 896                         13500000 : 6500000;
 897
 898         if (modulation < 4)
 899                 bitrate *= (modulation + 1);
 900         else if (modulation == 4)
 901                 bitrate *= (modulation + 2);
 902         else
 903                 bitrate *= (modulation + 3);
 904
 905         bitrate *= streams;
 906
 907         if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
 908                 bitrate = (bitrate / 9) * 10;
 909
 910         /* do NOT round down here */
 911         return (bitrate + 50000) / 100000;
 912 }
 913
 914 int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
 915                                  u32 beacon_int)
 916 {
 917         struct wireless_dev *wdev;
 918         int res = 0;
 919
 920         if (!beacon_int)
 921                 return -EINVAL;
 922
 923         mutex_lock(&rdev->devlist_mtx);
 924
 925         list_for_each_entry(wdev, &rdev->netdev_list, list) {
 926                 if (!wdev->beacon_interval)
 927                         continue;
 928                 if (wdev->beacon_interval != beacon_int) {
 929                         res = -EINVAL;
 930                         break;
 931                 }
 932         }
 933
 934         mutex_unlock(&rdev->devlist_mtx);
 935
 936         return res;
 937 }
 938
 939 int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
 940                                   struct wireless_dev *wdev,
 941                                   enum nl80211_iftype iftype)
 942 {
 943         struct wireless_dev *wdev_iter;
 944         int num[NUM_NL80211_IFTYPES];
 945         int total = 1;
 946         int i, j;
 947
 948         ASSERT_RTNL();
 949
 950         /* Always allow software iftypes */
 951         if (rdev->wiphy.software_iftypes & BIT(iftype))
 952                 return 0;
 953
 954         /*
 955          * Drivers will gradually all set this flag, until all
 956          * have it we only enforce for those that set it.
 957          */
 958         if (!(rdev->wiphy.flags & WIPHY_FLAG_ENFORCE_COMBINATIONS))
 959                 return 0;
 960
 961         memset(num, 0, sizeof(num));
 962
 963         num[iftype] = 1;
 964
 965         mutex_lock(&rdev->devlist_mtx);
 966         list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {
 967                 if (wdev_iter == wdev)
 968                         continue;
 969                 if (!netif_running(wdev_iter->netdev))
 970                         continue;
 971
 972                 if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))
 973                         continue;
 974
 975                 num[wdev_iter->iftype]++;
 976                 total++;
 977         }
 978         mutex_unlock(&rdev->devlist_mtx);
 979
 980         for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) {
 981                 const struct ieee80211_iface_combination *c;
 982                 struct ieee80211_iface_limit *limits;
 983
 984                 c = &rdev->wiphy.iface_combinations[i];
 985
 986                 limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
 987                                  GFP_KERNEL);
 988                 if (!limits)
 989                         return -ENOMEM;
 990                 if (total > c->max_interfaces)
 991                         goto cont;
 992
 993                 for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
 994                         if (rdev->wiphy.software_iftypes & BIT(iftype))
 995                                 continue;
 996                         for (j = 0; j < c->n_limits; j++) {
 997                                 if (!(limits[j].types & iftype))
 998                                         continue;
 999                                 if (limits[j].max < num[iftype])
1000                                         goto cont;
1001                                 limits[j].max -= num[iftype];
1002                         }
1003                 }
1004                 /* yay, it fits */
1005                 kfree(limits);
1006                 return 0;
1007  cont:
1008                 kfree(limits);
1009         }
1010
1011         return -EBUSY;
1012 }
1013
1014 int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
1015                            const u8 *rates, unsigned int n_rates,
1016                            u32 *mask)
1017 {
1018         int i, j;
1019
1020         if (!sband)
1021                 return -EINVAL;
1022
1023         if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
1024                 return -EINVAL;
1025
1026         *mask = 0;
1027
1028         for (i = 0; i < n_rates; i++) {
1029                 int rate = (rates[i] & 0x7f) * 5;
1030                 bool found = false;
1031
1032                 for (j = 0; j < sband->n_bitrates; j++) {
1033                         if (sband->bitrates[j].bitrate == rate) {
1034                                 found = true;
1035                                 *mask |= BIT(j);
1036                                 break;
1037                         }
1038                 }
1039                 if (!found)
1040                         return -EINVAL;
1041         }
1042
1043         /*
1044          * mask must have at least one bit set here since we
1045          * didn't accept a 0-length rates array nor allowed
1046          * entries in the array that didn't exist
1047          */
1048
1049         return 0;
1050 }
1051
1052 u32 ieee802_11_parse_elems_crc(u8 *start, size_t len,
1053                                struct ieee802_11_elems *elems,
1054                                u64 filter, u32 crc)
1055 {
1056         size_t left = len;
1057         u8 *pos = start;
1058         bool calc_crc = filter != 0;
1059
1060         memset(elems, 0, sizeof(*elems));
1061         elems->ie_start = start;
1062         elems->total_len = len;
1063
1064         while (left >= 2) {
1065                 u8 id, elen;
1066
1067                 id = *pos++;
1068                 elen = *pos++;
1069                 left -= 2;
1070
1071                 if (elen > left)
1072                         break;
1073
1074                 if (calc_crc && id < 64 && (filter & (1ULL << id)))
1075                         crc = crc32_be(crc, pos - 2, elen + 2);
1076
1077                 switch (id) {
1078                 case WLAN_EID_SSID:
1079                         elems->ssid = pos;
1080                         elems->ssid_len = elen;
1081                         break;
1082                 case WLAN_EID_SUPP_RATES:
1083                         elems->supp_rates = pos;
1084                         elems->supp_rates_len = elen;
1085                         break;
1086                 case WLAN_EID_FH_PARAMS:
1087                         elems->fh_params = pos;
1088                         elems->fh_params_len = elen;
1089                         break;
1090                 case WLAN_EID_DS_PARAMS:
1091                         elems->ds_params = pos;
1092                         elems->ds_params_len = elen;
1093                         break;
1094                 case WLAN_EID_CF_PARAMS:
1095                         elems->cf_params = pos;
1096                         elems->cf_params_len = elen;
1097                         break;
1098                 case WLAN_EID_TIM:
1099                         if (elen >= sizeof(struct ieee80211_tim_ie)) {
1100                                 elems->tim = (void *)pos;
1101                                 elems->tim_len = elen;
1102                         }
1103                         break;
1104                 case WLAN_EID_IBSS_PARAMS:
1105                         elems->ibss_params = pos;
1106                         elems->ibss_params_len = elen;
1107                         break;
1108                 case WLAN_EID_CHALLENGE:
1109                         elems->challenge = pos;
1110                         elems->challenge_len = elen;
1111                         break;
1112                 case WLAN_EID_VENDOR_SPECIFIC:
1113                         if (elen >= 4 && pos[0] == 0x00 && pos[1] == 0x50 &&
1114                             pos[2] == 0xf2) {
1115                                 /* Microsoft OUI (00:50:F2) */
1116
1117                                 if (calc_crc)
1118                                         crc = crc32_be(crc, pos - 2, elen + 2);
1119
1120                                 if (pos[3] == 1) {
1121                                         /* OUI Type 1 - WPA IE */
1122                                         elems->wpa = pos;
1123                                         elems->wpa_len = elen;
1124                                 } else if (elen >= 5 && pos[3] == 2) {
1125                                         /* OUI Type 2 - WMM IE */
1126                                         if (pos[4] == 0) {
1127                                                 elems->wmm_info = pos;
1128                                                 elems->wmm_info_len = elen;
1129                                         } else if (pos[4] == 1) {
1130                                                 elems->wmm_param = pos;
1131                                                 elems->wmm_param_len = elen;
1132                                         }
1133                                 }
1134                         }
1135                         break;
1136                 case WLAN_EID_RSN:
1137                         elems->rsn = pos;
1138                         elems->rsn_len = elen;
1139                         break;
1140                 case WLAN_EID_ERP_INFO:
1141                         elems->erp_info = pos;
1142                         elems->erp_info_len = elen;
1143                         break;
1144                 case WLAN_EID_EXT_SUPP_RATES:
1145                         elems->ext_supp_rates = pos;
1146                         elems->ext_supp_rates_len = elen;
1147                         break;
1148                 case WLAN_EID_HT_CAPABILITY:
1149                         if (elen >= sizeof(struct ieee80211_ht_cap))
1150                                 elems->ht_cap_elem = (void *)pos;
1151                         break;
1152                 case WLAN_EID_HT_INFORMATION:
1153                         if (elen >= sizeof(struct ieee80211_ht_info))
1154                                 elems->ht_info_elem = (void *)pos;
1155                         break;
1156                 case WLAN_EID_MESH_ID:
1157                         elems->mesh_id = pos;
1158                         elems->mesh_id_len = elen;
1159                         break;
1160                 case WLAN_EID_MESH_CONFIG:
1161                         if (elen >= sizeof(struct ieee80211_meshconf_ie))
1162                                 elems->mesh_config = (void *)pos;
1163                         break;
1164                 case WLAN_EID_PEER_MGMT:
1165                         elems->peering = pos;
1166                         elems->peering_len = elen;
1167                         break;
1168                 case WLAN_EID_PREQ:
1169                         elems->preq = pos;
1170                         elems->preq_len = elen;
1171                         break;
1172                 case WLAN_EID_PREP:
1173                         elems->prep = pos;
1174                         elems->prep_len = elen;
1175                         break;
1176                 case WLAN_EID_PERR:
1177                         elems->perr = pos;
1178                         elems->perr_len = elen;
1179                         break;
1180                 case WLAN_EID_RANN:
1181                         if (elen >= sizeof(struct ieee80211_rann_ie))
1182                                 elems->rann = (void *)pos;
1183                         break;
1184                 case WLAN_EID_CHANNEL_SWITCH:
1185                         elems->ch_switch_elem = pos;
1186                         elems->ch_switch_elem_len = elen;
1187                         break;
1188                 case WLAN_EID_QUIET:
1189                         if (!elems->quiet_elem) {
1190                                 elems->quiet_elem = pos;
1191                                 elems->quiet_elem_len = elen;
1192                         }
1193                         elems->num_of_quiet_elem++;
1194                         break;
1195                 case WLAN_EID_COUNTRY:
1196                         elems->country_elem = pos;
1197                         elems->country_elem_len = elen;
1198                         break;
1199                 case WLAN_EID_PWR_CONSTRAINT:
1200                         elems->pwr_constr_elem = pos;
1201                         elems->pwr_constr_elem_len = elen;
1202                         break;
1203                 case WLAN_EID_TIMEOUT_INTERVAL:
1204                         elems->timeout_int = pos;
1205                         elems->timeout_int_len = elen;
1206                         break;
1207                 default:
1208                         break;
1209                 }
1210
1211                 left -= elen;
1212                 pos += elen;
1213         }
1214
1215         return crc;
1216 }
1217 EXPORT_SYMBOL(ieee802_11_parse_elems_crc);