net/wireless/util.c

   1 /*
   2  * Wireless utility functions
   3  *
   4  * Copyright 2007-2009  Johannes Berg <johannes@sipsolutions.net>
   5  */
   6 #include <linux/export.h>
   7 #include <linux/bitops.h>
   8 #include <linux/etherdevice.h>
   9 #include <linux/slab.h>
  10 #include <net/cfg80211.h>
  11 #include <net/ip.h>
  12 #include <net/dsfield.h>
  13 #include "core.h"
  14
  15 struct ieee80211_rate *
  16 ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
  17                             u32 basic_rates, int bitrate)
  18 {
  19         struct ieee80211_rate *result = &sband->bitrates[0];
  20         int i;
  21
  22         for (i = 0; i < sband->n_bitrates; i++) {
  23                 if (!(basic_rates & BIT(i)))
  24                         continue;
  25                 if (sband->bitrates[i].bitrate > bitrate)
  26                         continue;
  27                 result = &sband->bitrates[i];
  28         }
  29
  30         return result;
  31 }
  32 EXPORT_SYMBOL(ieee80211_get_response_rate);
  33
  34 int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
  35 {
  36         /* see 802.11 17.3.8.3.2 and Annex J
  37          * there are overlapping channel numbers in 5GHz and 2GHz bands */
  38         if (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 unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
 244 {
 245         unsigned int hdrlen = 24;
 246
 247         if (ieee80211_is_data(fc)) {
 248                 if (ieee80211_has_a4(fc))
 249                         hdrlen = 30;
 250                 if (ieee80211_is_data_qos(fc)) {
 251                         hdrlen += IEEE80211_QOS_CTL_LEN;
 252                         if (ieee80211_has_order(fc))
 253                                 hdrlen += IEEE80211_HT_CTL_LEN;
 254                 }
 255                 goto out;
 256         }
 257
 258         if (ieee80211_is_ctl(fc)) {
 259                 /*
 260                  * ACK and CTS are 10 bytes, all others 16. To see how
 261                  * to get this condition consider
 262                  *   subtype mask:   0b0000000011110000 (0x00F0)
 263                  *   ACK subtype:    0b0000000011010000 (0x00D0)
 264                  *   CTS subtype:    0b0000000011000000 (0x00C0)
 265                  *   bits that matter:         ^^^      (0x00E0)
 266                  *   value of those: 0b0000000011000000 (0x00C0)
 267                  */
 268                 if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
 269                         hdrlen = 10;
 270                 else
 271                         hdrlen = 16;
 272         }
 273 out:
 274         return hdrlen;
 275 }
 276 EXPORT_SYMBOL(ieee80211_hdrlen);
 277
 278 unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
 279 {
 280         const struct ieee80211_hdr *hdr =
 281                         (const struct ieee80211_hdr *)skb->data;
 282         unsigned int hdrlen;
 283
 284         if (unlikely(skb->len < 10))
 285                 return 0;
 286         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 287         if (unlikely(hdrlen > skb->len))
 288                 return 0;
 289         return hdrlen;
 290 }
 291 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
 292
 293 static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
 294 {
 295         int ae = meshhdr->flags & MESH_FLAGS_AE;
 296         /* 7.1.3.5a.2 */
 297         switch (ae) {
 298         case 0:
 299                 return 6;
 300         case MESH_FLAGS_AE_A4:
 301                 return 12;
 302         case MESH_FLAGS_AE_A5_A6:
 303                 return 18;
 304         case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
 305                 return 24;
 306         default:
 307                 return 6;
 308         }
 309 }
 310
 311 int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
 312                            enum nl80211_iftype iftype)
 313 {
 314         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 315         u16 hdrlen, ethertype;
 316         u8 *payload;
 317         u8 dst[ETH_ALEN];
 318         u8 src[ETH_ALEN] __aligned(2);
 319
 320         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
 321                 return -1;
 322
 323         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 324
 325         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
 326          * header
 327          * IEEE 802.11 address fields:
 328          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
 329          *   0     0   DA    SA    BSSID n/a
 330          *   0     1   DA    BSSID SA    n/a
 331          *   1     0   BSSID SA    DA    n/a
 332          *   1     1   RA    TA    DA    SA
 333          */
 334         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
 335         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
 336
 337         switch (hdr->frame_control &
 338                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
 339         case cpu_to_le16(IEEE80211_FCTL_TODS):
 340                 if (unlikely(iftype != NL80211_IFTYPE_AP &&
 341                              iftype != NL80211_IFTYPE_AP_VLAN &&
 342                              iftype != NL80211_IFTYPE_P2P_GO))
 343                         return -1;
 344                 break;
 345         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
 346                 if (unlikely(iftype != NL80211_IFTYPE_WDS &&
 347                              iftype != NL80211_IFTYPE_MESH_POINT &&
 348                              iftype != NL80211_IFTYPE_AP_VLAN &&
 349                              iftype != NL80211_IFTYPE_STATION))
 350                         return -1;
 351                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 352                         struct ieee80211s_hdr *meshdr =
 353                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 354                         /* make sure meshdr->flags is on the linear part */
 355                         if (!pskb_may_pull(skb, hdrlen + 1))
 356                                 return -1;
 357                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
 358                                 skb_copy_bits(skb, hdrlen +
 359                                         offsetof(struct ieee80211s_hdr, eaddr1),
 360                                         dst, ETH_ALEN);
 361                                 skb_copy_bits(skb, hdrlen +
 362                                         offsetof(struct ieee80211s_hdr, eaddr2),
 363                                         src, ETH_ALEN);
 364                         }
 365                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 366                 }
 367                 break;
 368         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
 369                 if ((iftype != NL80211_IFTYPE_STATION &&
 370                      iftype != NL80211_IFTYPE_P2P_CLIENT &&
 371                      iftype != NL80211_IFTYPE_MESH_POINT) ||
 372                     (is_multicast_ether_addr(dst) &&
 373                      !compare_ether_addr(src, addr)))
 374                         return -1;
 375                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 376                         struct ieee80211s_hdr *meshdr =
 377                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 378                         /* make sure meshdr->flags is on the linear part */
 379                         if (!pskb_may_pull(skb, hdrlen + 1))
 380                                 return -1;
 381                         if (meshdr->flags & MESH_FLAGS_AE_A4)
 382                                 skb_copy_bits(skb, hdrlen +
 383                                         offsetof(struct ieee80211s_hdr, eaddr1),
 384                                         src, ETH_ALEN);
 385                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 386                 }
 387                 break;
 388         case cpu_to_le16(0):
 389                 if (iftype != NL80211_IFTYPE_ADHOC &&
 390                     iftype != NL80211_IFTYPE_STATION)
 391                                 return -1;
 392                 break;
 393         }
 394
 395         if (!pskb_may_pull(skb, hdrlen + 8))
 396                 return -1;
 397
 398         payload = skb->data + hdrlen;
 399         ethertype = (payload[6] << 8) | payload[7];
 400
 401         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 402                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 403                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
 404                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
 405                  * replace EtherType */
 406                 skb_pull(skb, hdrlen + 6);
 407                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
 408                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
 409         } else {
 410                 struct ethhdr *ehdr;
 411                 __be16 len;
 412
 413                 skb_pull(skb, hdrlen);
 414                 len = htons(skb->len);
 415                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
 416                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
 417                 memcpy(ehdr->h_source, src, ETH_ALEN);
 418                 ehdr->h_proto = len;
 419         }
 420         return 0;
 421 }
 422 EXPORT_SYMBOL(ieee80211_data_to_8023);
 423
 424 int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
 425                              enum nl80211_iftype iftype, u8 *bssid, bool qos)
 426 {
 427         struct ieee80211_hdr hdr;
 428         u16 hdrlen, ethertype;
 429         __le16 fc;
 430         const u8 *encaps_data;
 431         int encaps_len, skip_header_bytes;
 432         int nh_pos, h_pos;
 433         int head_need;
 434
 435         if (unlikely(skb->len < ETH_HLEN))
 436                 return -EINVAL;
 437
 438         nh_pos = skb_network_header(skb) - skb->data;
 439         h_pos = skb_transport_header(skb) - skb->data;
 440
 441         /* convert Ethernet header to proper 802.11 header (based on
 442          * operation mode) */
 443         ethertype = (skb->data[12] << 8) | skb->data[13];
 444         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
 445
 446         switch (iftype) {
 447         case NL80211_IFTYPE_AP:
 448         case NL80211_IFTYPE_AP_VLAN:
 449         case NL80211_IFTYPE_P2P_GO:
 450                 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 451                 /* DA BSSID SA */
 452                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 453                 memcpy(hdr.addr2, addr, ETH_ALEN);
 454                 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
 455                 hdrlen = 24;
 456                 break;
 457         case NL80211_IFTYPE_STATION:
 458         case NL80211_IFTYPE_P2P_CLIENT:
 459                 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
 460                 /* BSSID SA DA */
 461                 memcpy(hdr.addr1, bssid, ETH_ALEN);
 462                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 463                 memcpy(hdr.addr3, skb->data, ETH_ALEN);
 464                 hdrlen = 24;
 465                 break;
 466         case NL80211_IFTYPE_ADHOC:
 467                 /* DA SA BSSID */
 468                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 469                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 470                 memcpy(hdr.addr3, bssid, ETH_ALEN);
 471                 hdrlen = 24;
 472                 break;
 473         default:
 474                 return -EOPNOTSUPP;
 475         }
 476
 477         if (qos) {
 478                 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
 479                 hdrlen += 2;
 480         }
 481
 482         hdr.frame_control = fc;
 483         hdr.duration_id = 0;
 484         hdr.seq_ctrl = 0;
 485
 486         skip_header_bytes = ETH_HLEN;
 487         if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
 488                 encaps_data = bridge_tunnel_header;
 489                 encaps_len = sizeof(bridge_tunnel_header);
 490                 skip_header_bytes -= 2;
 491         } else if (ethertype > 0x600) {
 492                 encaps_data = rfc1042_header;
 493                 encaps_len = sizeof(rfc1042_header);
 494                 skip_header_bytes -= 2;
 495         } else {
 496                 encaps_data = NULL;
 497                 encaps_len = 0;
 498         }
 499
 500         skb_pull(skb, skip_header_bytes);
 501         nh_pos -= skip_header_bytes;
 502         h_pos -= skip_header_bytes;
 503
 504         head_need = hdrlen + encaps_len - skb_headroom(skb);
 505
 506         if (head_need > 0 || skb_cloned(skb)) {
 507                 head_need = max(head_need, 0);
 508                 if (head_need)
 509                         skb_orphan(skb);
 510
 511                 if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC))
 512                         return -ENOMEM;
 513
 514                 skb->truesize += head_need;
 515         }
 516
 517         if (encaps_data) {
 518                 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
 519                 nh_pos += encaps_len;
 520                 h_pos += encaps_len;
 521         }
 522
 523         memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
 524
 525         nh_pos += hdrlen;
 526         h_pos += hdrlen;
 527
 528         /* Update skb pointers to various headers since this modified frame
 529          * is going to go through Linux networking code that may potentially
 530          * need things like pointer to IP header. */
 531         skb_set_mac_header(skb, 0);
 532         skb_set_network_header(skb, nh_pos);
 533         skb_set_transport_header(skb, h_pos);
 534
 535         return 0;
 536 }
 537 EXPORT_SYMBOL(ieee80211_data_from_8023);
 538
 539
 540 void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
 541                               const u8 *addr, enum nl80211_iftype iftype,
 542                               const unsigned int extra_headroom,
 543                               bool has_80211_header)
 544 {
 545         struct sk_buff *frame = NULL;
 546         u16 ethertype;
 547         u8 *payload;
 548         const struct ethhdr *eth;
 549         int remaining, err;
 550         u8 dst[ETH_ALEN], src[ETH_ALEN];
 551
 552         if (has_80211_header) {
 553                 err = ieee80211_data_to_8023(skb, addr, iftype);
 554                 if (err)
 555                         goto out;
 556
 557                 /* skip the wrapping header */
 558                 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
 559                 if (!eth)
 560                         goto out;
 561         } else {
 562                 eth = (struct ethhdr *) skb->data;
 563         }
 564
 565         while (skb != frame) {
 566                 u8 padding;
 567                 __be16 len = eth->h_proto;
 568                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
 569
 570                 remaining = skb->len;
 571                 memcpy(dst, eth->h_dest, ETH_ALEN);
 572                 memcpy(src, eth->h_source, ETH_ALEN);
 573
 574                 padding = (4 - subframe_len) & 0x3;
 575                 /* the last MSDU has no padding */
 576                 if (subframe_len > remaining)
 577                         goto purge;
 578
 579                 skb_pull(skb, sizeof(struct ethhdr));
 580                 /* reuse skb for the last subframe */
 581                 if (remaining <= subframe_len + padding)
 582                         frame = skb;
 583                 else {
 584                         unsigned int hlen = ALIGN(extra_headroom, 4);
 585                         /*
 586                          * Allocate and reserve two bytes more for payload
 587                          * alignment since sizeof(struct ethhdr) is 14.
 588                          */
 589                         frame = dev_alloc_skb(hlen + subframe_len + 2);
 590                         if (!frame)
 591                                 goto purge;
 592
 593                         skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
 594                         memcpy(skb_put(frame, ntohs(len)), skb->data,
 595                                 ntohs(len));
 596
 597                         eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
 598                                                         padding);
 599                         if (!eth) {
 600                                 dev_kfree_skb(frame);
 601                                 goto purge;
 602                         }
 603                 }
 604
 605                 skb_reset_network_header(frame);
 606                 frame->dev = skb->dev;
 607                 frame->priority = skb->priority;
 608
 609                 payload = frame->data;
 610                 ethertype = (payload[6] << 8) | payload[7];
 611
 612                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 613                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 614                            compare_ether_addr(payload,
 615                                               bridge_tunnel_header) == 0)) {
 616                         /* remove RFC1042 or Bridge-Tunnel
 617                          * encapsulation and replace EtherType */
 618                         skb_pull(frame, 6);
 619                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 620                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 621                 } else {
 622                         memcpy(skb_push(frame, sizeof(__be16)), &len,
 623                                 sizeof(__be16));
 624                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 625                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 626                 }
 627                 __skb_queue_tail(list, frame);
 628         }
 629
 630         return;
 631
 632  purge:
 633         __skb_queue_purge(list);
 634  out:
 635         dev_kfree_skb(skb);
 636 }
 637 EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
 638
 639 /* Given a data frame determine the 802.1p/1d tag to use. */
 640 unsigned int cfg80211_classify8021d(struct sk_buff *skb)
 641 {
 642         unsigned int dscp;
 643
 644         /* skb->priority values from 256->263 are magic values to
 645          * directly indicate a specific 802.1d priority.  This is used
 646          * to allow 802.1d priority to be passed directly in from VLAN
 647          * tags, etc.
 648          */
 649         if (skb->priority >= 256 && skb->priority <= 263)
 650                 return skb->priority - 256;
 651
 652         switch (skb->protocol) {
 653         case htons(ETH_P_IP):
 654                 dscp = ipv4_get_dsfield(ip_hdr(skb)) & 0xfc;
 655                 break;
 656         case htons(ETH_P_IPV6):
 657                 dscp = ipv6_get_dsfield(ipv6_hdr(skb)) & 0xfc;
 658                 break;
 659         default:
 660                 return 0;
 661         }
 662
 663         return dscp >> 5;
 664 }
 665 EXPORT_SYMBOL(cfg80211_classify8021d);
 666
 667 const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
 668 {
 669         u8 *end, *pos;
 670
 671         pos = bss->information_elements;
 672         if (pos == NULL)
 673                 return NULL;
 674         end = pos + bss->len_information_elements;
 675
 676         while (pos + 1 < end) {
 677                 if (pos + 2 + pos[1] > end)
 678                         break;
 679                 if (pos[0] == ie)
 680                         return pos;
 681                 pos += 2 + pos[1];
 682         }
 683
 684         return NULL;
 685 }
 686 EXPORT_SYMBOL(ieee80211_bss_get_ie);
 687
 688 void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
 689 {
 690         struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
 691         struct net_device *dev = wdev->netdev;
 692         int i;
 693
 694         if (!wdev->connect_keys)
 695                 return;
 696
 697         for (i = 0; i < 6; i++) {
 698                 if (!wdev->connect_keys->params[i].cipher)
 699                         continue;
 700                 if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
 701                                         &wdev->connect_keys->params[i])) {
 702                         netdev_err(dev, "failed to set key %d\n", i);
 703                         continue;
 704                 }
 705                 if (wdev->connect_keys->def == i)
 706                         if (rdev->ops->set_default_key(wdev->wiphy, dev,
 707                                                        i, true, true)) {
 708                                 netdev_err(dev, "failed to set defkey %d\n", i);
 709                                 continue;
 710                         }
 711                 if (wdev->connect_keys->defmgmt == i)
 712                         if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
 713                                 netdev_err(dev, "failed to set mgtdef %d\n", i);
 714         }
 715
 716         kfree(wdev->connect_keys);
 717         wdev->connect_keys = NULL;
 718 }
 719
 720 static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
 721 {
 722         struct cfg80211_event *ev;
 723         unsigned long flags;
 724         const u8 *bssid = NULL;
 725
 726         spin_lock_irqsave(&wdev->event_lock, flags);
 727         while (!list_empty(&wdev->event_list)) {
 728                 ev = list_first_entry(&wdev->event_list,
 729                                       struct cfg80211_event, list);
 730                 list_del(&ev->list);
 731                 spin_unlock_irqrestore(&wdev->event_lock, flags);
 732
 733                 wdev_lock(wdev);
 734                 switch (ev->type) {
 735                 case EVENT_CONNECT_RESULT:
 736                         if (!is_zero_ether_addr(ev->cr.bssid))
 737                                 bssid = ev->cr.bssid;
 738                         __cfg80211_connect_result(
 739                                 wdev->netdev, bssid,
 740                                 ev->cr.req_ie, ev->cr.req_ie_len,
 741                                 ev->cr.resp_ie, ev->cr.resp_ie_len,
 742                                 ev->cr.status,
 743                                 ev->cr.status == WLAN_STATUS_SUCCESS,
 744                                 NULL);
 745                         break;
 746                 case EVENT_ROAMED:
 747                         __cfg80211_roamed(wdev, ev->rm.bss, ev->rm.req_ie,
 748                                           ev->rm.req_ie_len, ev->rm.resp_ie,
 749                                           ev->rm.resp_ie_len);
 750                         break;
 751                 case EVENT_DISCONNECTED:
 752                         __cfg80211_disconnected(wdev->netdev,
 753                                                 ev->dc.ie, ev->dc.ie_len,
 754                                                 ev->dc.reason, true);
 755                         break;
 756                 case EVENT_IBSS_JOINED:
 757                         __cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
 758                         break;
 759                 }
 760                 wdev_unlock(wdev);
 761
 762                 kfree(ev);
 763
 764                 spin_lock_irqsave(&wdev->event_lock, flags);
 765         }
 766         spin_unlock_irqrestore(&wdev->event_lock, flags);
 767 }
 768
 769 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
 770 {
 771         struct wireless_dev *wdev;
 772
 773         ASSERT_RTNL();
 774         ASSERT_RDEV_LOCK(rdev);
 775
 776         mutex_lock(&rdev->devlist_mtx);
 777
 778         list_for_each_entry(wdev, &rdev->netdev_list, list)
 779                 cfg80211_process_wdev_events(wdev);
 780
 781         mutex_unlock(&rdev->devlist_mtx);
 782 }
 783
 784 int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 785                           struct net_device *dev, enum nl80211_iftype ntype,
 786                           u32 *flags, struct vif_params *params)
 787 {
 788         int err;
 789         enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
 790
 791         ASSERT_RDEV_LOCK(rdev);
 792
 793         /* don't support changing VLANs, you just re-create them */
 794         if (otype == NL80211_IFTYPE_AP_VLAN)
 795                 return -EOPNOTSUPP;
 796
 797         if (!rdev->ops->change_virtual_intf ||
 798             !(rdev->wiphy.interface_modes & (1 << ntype)))
 799                 return -EOPNOTSUPP;
 800
 801         /* if it's part of a bridge, reject changing type to station/ibss */
 802         if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
 803             (ntype == NL80211_IFTYPE_ADHOC ||
 804              ntype == NL80211_IFTYPE_STATION ||
 805              ntype == NL80211_IFTYPE_P2P_CLIENT))
 806                 return -EBUSY;
 807
 808         if (ntype != otype) {
 809                 err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
 810                                                     ntype);
 811                 if (err)
 812                         return err;
 813
 814                 dev->ieee80211_ptr->use_4addr = false;
 815                 dev->ieee80211_ptr->mesh_id_up_len = 0;
 816
 817                 switch (otype) {
 818                 case NL80211_IFTYPE_ADHOC:
 819                         cfg80211_leave_ibss(rdev, dev, false);
 820                         break;
 821                 case NL80211_IFTYPE_STATION:
 822                 case NL80211_IFTYPE_P2P_CLIENT:
 823                         cfg80211_disconnect(rdev, dev,
 824                                             WLAN_REASON_DEAUTH_LEAVING, true);
 825                         break;
 826                 case NL80211_IFTYPE_MESH_POINT:
 827                         /* mesh should be handled? */
 828                         break;
 829                 default:
 830                         break;
 831                 }
 832
 833                 cfg80211_process_rdev_events(rdev);
 834         }
 835
 836         err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
 837                                              ntype, flags, params);
 838
 839         WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
 840
 841         if (!err && params && params->use_4addr != -1)
 842                 dev->ieee80211_ptr->use_4addr = params->use_4addr;
 843
 844         if (!err) {
 845                 dev->priv_flags &= ~IFF_DONT_BRIDGE;
 846                 switch (ntype) {
 847                 case NL80211_IFTYPE_STATION:
 848                         if (dev->ieee80211_ptr->use_4addr)
 849                                 break;
 850                         /* fall through */
 851                 case NL80211_IFTYPE_P2P_CLIENT:
 852                 case NL80211_IFTYPE_ADHOC:
 853                         dev->priv_flags |= IFF_DONT_BRIDGE;
 854                         break;
 855                 case NL80211_IFTYPE_P2P_GO:
 856                 case NL80211_IFTYPE_AP:
 857                 case NL80211_IFTYPE_AP_VLAN:
 858                 case NL80211_IFTYPE_WDS:
 859                 case NL80211_IFTYPE_MESH_POINT:
 860                         /* bridging OK */
 861                         break;
 862                 case NL80211_IFTYPE_MONITOR:
 863                         /* monitor can't bridge anyway */
 864                         break;
 865                 case NL80211_IFTYPE_UNSPECIFIED:
 866                 case NUM_NL80211_IFTYPES:
 867                         /* not happening */
 868                         break;
 869                 }
 870         }
 871
 872         return err;
 873 }
 874
 875 u16 cfg80211_calculate_bitrate(struct rate_info *rate)
 876 {
 877         int modulation, streams, bitrate;
 878
 879         if (!(rate->flags & RATE_INFO_FLAGS_MCS))
 880                 return rate->legacy;
 881
 882         /* the formula below does only work for MCS values smaller than 32 */
 883         if (rate->mcs >= 32)
 884                 return 0;
 885
 886         modulation = rate->mcs & 7;
 887         streams = (rate->mcs >> 3) + 1;
 888
 889         bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
 890                         13500000 : 6500000;
 891
 892         if (modulation < 4)
 893                 bitrate *= (modulation + 1);
 894         else if (modulation == 4)
 895                 bitrate *= (modulation + 2);
 896         else
 897                 bitrate *= (modulation + 3);
 898
 899         bitrate *= streams;
 900
 901         if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
 902                 bitrate = (bitrate / 9) * 10;
 903
 904         /* do NOT round down here */
 905         return (bitrate + 50000) / 100000;
 906 }
 907
 908 int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
 909                                  u32 beacon_int)
 910 {
 911         struct wireless_dev *wdev;
 912         int res = 0;
 913
 914         if (!beacon_int)
 915                 return -EINVAL;
 916
 917         mutex_lock(&rdev->devlist_mtx);
 918
 919         list_for_each_entry(wdev, &rdev->netdev_list, list) {
 920                 if (!wdev->beacon_interval)
 921                         continue;
 922                 if (wdev->beacon_interval != beacon_int) {
 923                         res = -EINVAL;
 924                         break;
 925                 }
 926         }
 927
 928         mutex_unlock(&rdev->devlist_mtx);
 929
 930         return res;
 931 }
 932
 933 int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
 934                                   struct wireless_dev *wdev,
 935                                   enum nl80211_iftype iftype)
 936 {
 937         struct wireless_dev *wdev_iter;
 938         int num[NUM_NL80211_IFTYPES];
 939         int total = 1;
 940         int i, j;
 941
 942         ASSERT_RTNL();
 943
 944         /* Always allow software iftypes */
 945         if (rdev->wiphy.software_iftypes & BIT(iftype))
 946                 return 0;
 947
 948         /*
 949          * Drivers will gradually all set this flag, until all
 950          * have it we only enforce for those that set it.
 951          */
 952         if (!(rdev->wiphy.flags & WIPHY_FLAG_ENFORCE_COMBINATIONS))
 953                 return 0;
 954
 955         memset(num, 0, sizeof(num));
 956
 957         num[iftype] = 1;
 958
 959         mutex_lock(&rdev->devlist_mtx);
 960         list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {
 961                 if (wdev_iter == wdev)
 962                         continue;
 963                 if (!netif_running(wdev_iter->netdev))
 964                         continue;
 965
 966                 if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))
 967                         continue;
 968
 969                 num[wdev_iter->iftype]++;
 970                 total++;
 971         }
 972         mutex_unlock(&rdev->devlist_mtx);
 973
 974         for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) {
 975                 const struct ieee80211_iface_combination *c;
 976                 struct ieee80211_iface_limit *limits;
 977
 978                 c = &rdev->wiphy.iface_combinations[i];
 979
 980                 limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
 981                                  GFP_KERNEL);
 982                 if (!limits)
 983                         return -ENOMEM;
 984                 if (total > c->max_interfaces)
 985                         goto cont;
 986
 987                 for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
 988                         if (rdev->wiphy.software_iftypes & BIT(iftype))
 989                                 continue;
 990                         for (j = 0; j < c->n_limits; j++) {
 991                                 if (!(limits[j].types & iftype))
 992                                         continue;
 993                                 if (limits[j].max < num[iftype])
 994                                         goto cont;
 995                                 limits[j].max -= num[iftype];
 996                         }
 997                 }
 998                 /* yay, it fits */
 999                 kfree(limits);
1000                 return 0;
1001  cont:
1002                 kfree(limits);
1003         }
1004
1005         return -EBUSY;
1006 }
1007
1008 int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
1009                            const u8 *rates, unsigned int n_rates,
1010                            u32 *mask)
1011 {
1012         int i, j;
1013
1014         if (!sband)
1015                 return -EINVAL;
1016
1017         if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
1018                 return -EINVAL;
1019
1020         *mask = 0;
1021
1022         for (i = 0; i < n_rates; i++) {
1023                 int rate = (rates[i] & 0x7f) * 5;
1024                 bool found = false;
1025
1026                 for (j = 0; j < sband->n_bitrates; j++) {
1027                         if (sband->bitrates[j].bitrate == rate) {
1028                                 found = true;
1029                                 *mask |= BIT(j);
1030                                 break;
1031                         }
1032                 }
1033                 if (!found)
1034                         return -EINVAL;
1035         }
1036
1037         /*
1038          * mask must have at least one bit set here since we
1039          * didn't accept a 0-length rates array nor allowed
1040          * entries in the array that didn't exist
1041          */
1042
1043         return 0;
1044 }
1045
1046 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
1047 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
1048 const unsigned char rfc1042_header[] __aligned(2) =
1049         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
1050 EXPORT_SYMBOL(rfc1042_header);
1051
1052 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
1053 const unsigned char bridge_tunnel_header[] __aligned(2) =
1054         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
1055 EXPORT_SYMBOL(bridge_tunnel_header);