net/wireless/util.c

   1 /*
   2  * Wireless utility functions
   3  *
   4  * Copyright 2007-2009  Johannes Berg <johannes@sipsolutions.net>
   5  */
   6 #include <linux/export.h>
   7 #include <linux/bitops.h>
   8 #include <linux/etherdevice.h>
   9 #include <linux/slab.h>
  10 #include <net/cfg80211.h>
  11 #include <net/ip.h>
  12 #include <net/dsfield.h>
  13 #include "core.h"
  14
  15 struct ieee80211_rate *
  16 ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
  17                             u32 basic_rates, int bitrate)
  18 {
  19         struct ieee80211_rate *result = &sband->bitrates[0];
  20         int i;
  21
  22         for (i = 0; i < sband->n_bitrates; i++) {
  23                 if (!(basic_rates & BIT(i)))
  24                         continue;
  25                 if (sband->bitrates[i].bitrate > bitrate)
  26                         continue;
  27                 result = &sband->bitrates[i];
  28         }
  29
  30         return result;
  31 }
  32 EXPORT_SYMBOL(ieee80211_get_response_rate);
  33
  34 int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
  35 {
  36         /* see 802.11 17.3.8.3.2 and Annex J
  37          * there are overlapping channel numbers in 5GHz and 2GHz bands */
  38         if (chan <= 0)
  39                 return 0; /* not supported */
  40         switch (band) {
  41         case IEEE80211_BAND_2GHZ:
  42                 if (chan == 14)
  43                         return 2484;
  44                 else if (chan < 14)
  45                         return 2407 + chan * 5;
  46                 break;
  47         case IEEE80211_BAND_5GHZ:
  48                 if (chan >= 182 && chan <= 196)
  49                         return 4000 + chan * 5;
  50                 else
  51                         return 5000 + chan * 5;
  52                 break;
  53         case IEEE80211_BAND_60GHZ:
  54                 if (chan < 5)
  55                         return 56160 + chan * 2160;
  56                 break;
  57         default:
  58                 ;
  59         }
  60         return 0; /* not supported */
  61 }
  62 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
  63
  64 int ieee80211_frequency_to_channel(int freq)
  65 {
  66         /* see 802.11 17.3.8.3.2 and Annex J */
  67         if (freq == 2484)
  68                 return 14;
  69         else if (freq < 2484)
  70                 return (freq - 2407) / 5;
  71         else if (freq >= 4910 && freq <= 4980)
  72                 return (freq - 4000) / 5;
  73         else if (freq <= 45000) /* DMG band lower limit */
  74                 return (freq - 5000) / 5;
  75         else if (freq >= 58320 && freq <= 64800)
  76                 return (freq - 56160) / 2160;
  77         else
  78                 return 0;
  79 }
  80 EXPORT_SYMBOL(ieee80211_frequency_to_channel);
  81
  82 struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
  83                                                   int freq)
  84 {
  85         enum ieee80211_band band;
  86         struct ieee80211_supported_band *sband;
  87         int i;
  88
  89         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
  90                 sband = wiphy->bands[band];
  91
  92                 if (!sband)
  93                         continue;
  94
  95                 for (i = 0; i < sband->n_channels; i++) {
  96                         if (sband->channels[i].center_freq == freq)
  97                                 return &sband->channels[i];
  98                 }
  99         }
 100
 101         return NULL;
 102 }
 103 EXPORT_SYMBOL(__ieee80211_get_channel);
 104
 105 static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
 106                                      enum ieee80211_band band)
 107 {
 108         int i, want;
 109
 110         switch (band) {
 111         case IEEE80211_BAND_5GHZ:
 112                 want = 3;
 113                 for (i = 0; i < sband->n_bitrates; i++) {
 114                         if (sband->bitrates[i].bitrate == 60 ||
 115                             sband->bitrates[i].bitrate == 120 ||
 116                             sband->bitrates[i].bitrate == 240) {
 117                                 sband->bitrates[i].flags |=
 118                                         IEEE80211_RATE_MANDATORY_A;
 119                                 want--;
 120                         }
 121                 }
 122                 WARN_ON(want);
 123                 break;
 124         case IEEE80211_BAND_2GHZ:
 125                 want = 7;
 126                 for (i = 0; i < sband->n_bitrates; i++) {
 127                         if (sband->bitrates[i].bitrate == 10) {
 128                                 sband->bitrates[i].flags |=
 129                                         IEEE80211_RATE_MANDATORY_B |
 130                                         IEEE80211_RATE_MANDATORY_G;
 131                                 want--;
 132                         }
 133
 134                         if (sband->bitrates[i].bitrate == 20 ||
 135                             sband->bitrates[i].bitrate == 55 ||
 136                             sband->bitrates[i].bitrate == 110 ||
 137                             sband->bitrates[i].bitrate == 60 ||
 138                             sband->bitrates[i].bitrate == 120 ||
 139                             sband->bitrates[i].bitrate == 240) {
 140                                 sband->bitrates[i].flags |=
 141                                         IEEE80211_RATE_MANDATORY_G;
 142                                 want--;
 143                         }
 144
 145                         if (sband->bitrates[i].bitrate != 10 &&
 146                             sband->bitrates[i].bitrate != 20 &&
 147                             sband->bitrates[i].bitrate != 55 &&
 148                             sband->bitrates[i].bitrate != 110)
 149                                 sband->bitrates[i].flags |=
 150                                         IEEE80211_RATE_ERP_G;
 151                 }
 152                 WARN_ON(want != 0 && want != 3 && want != 6);
 153                 break;
 154         case IEEE80211_BAND_60GHZ:
 155                 /* check for mandatory HT MCS 1..4 */
 156                 WARN_ON(!sband->ht_cap.ht_supported);
 157                 WARN_ON((sband->ht_cap.mcs.rx_mask[0] & 0x1e) != 0x1e);
 158                 break;
 159         case IEEE80211_NUM_BANDS:
 160                 WARN_ON(1);
 161                 break;
 162         }
 163 }
 164
 165 void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
 166 {
 167         enum ieee80211_band band;
 168
 169         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 170                 if (wiphy->bands[band])
 171                         set_mandatory_flags_band(wiphy->bands[band], band);
 172 }
 173
 174 bool cfg80211_supported_cipher_suite(struct wiphy *wiphy, u32 cipher)
 175 {
 176         int i;
 177         for (i = 0; i < wiphy->n_cipher_suites; i++)
 178                 if (cipher == wiphy->cipher_suites[i])
 179                         return true;
 180         return false;
 181 }
 182
 183 int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
 184                                    struct key_params *params, int key_idx,
 185                                    bool pairwise, const u8 *mac_addr)
 186 {
 187         if (key_idx > 5)
 188                 return -EINVAL;
 189
 190         if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
 191                 return -EINVAL;
 192
 193         if (pairwise && !mac_addr)
 194                 return -EINVAL;
 195
 196         /*
 197          * Disallow pairwise keys with non-zero index unless it's WEP
 198          * or a vendor specific cipher (because current deployments use
 199          * pairwise WEP keys with non-zero indices and for vendor specific
 200          * ciphers this should be validated in the driver or hardware level
 201          * - but 802.11i clearly specifies to use zero)
 202          */
 203         if (pairwise && key_idx &&
 204             ((params->cipher == WLAN_CIPHER_SUITE_TKIP) ||
 205              (params->cipher == WLAN_CIPHER_SUITE_CCMP) ||
 206              (params->cipher == WLAN_CIPHER_SUITE_AES_CMAC)))
 207                 return -EINVAL;
 208
 209         switch (params->cipher) {
 210         case WLAN_CIPHER_SUITE_WEP40:
 211                 if (params->key_len != WLAN_KEY_LEN_WEP40)
 212                         return -EINVAL;
 213                 break;
 214         case WLAN_CIPHER_SUITE_TKIP:
 215                 if (params->key_len != WLAN_KEY_LEN_TKIP)
 216                         return -EINVAL;
 217                 break;
 218         case WLAN_CIPHER_SUITE_CCMP:
 219                 if (params->key_len != WLAN_KEY_LEN_CCMP)
 220                         return -EINVAL;
 221                 break;
 222         case WLAN_CIPHER_SUITE_WEP104:
 223                 if (params->key_len != WLAN_KEY_LEN_WEP104)
 224                         return -EINVAL;
 225                 break;
 226         case WLAN_CIPHER_SUITE_AES_CMAC:
 227                 if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
 228                         return -EINVAL;
 229                 break;
 230         default:
 231                 /*
 232                  * We don't know anything about this algorithm,
 233                  * allow using it -- but the driver must check
 234                  * all parameters! We still check below whether
 235                  * or not the driver supports this algorithm,
 236                  * of course.
 237                  */
 238                 break;
 239         }
 240
 241         if (params->seq) {
 242                 switch (params->cipher) {
 243                 case WLAN_CIPHER_SUITE_WEP40:
 244                 case WLAN_CIPHER_SUITE_WEP104:
 245                         /* These ciphers do not use key sequence */
 246                         return -EINVAL;
 247                 case WLAN_CIPHER_SUITE_TKIP:
 248                 case WLAN_CIPHER_SUITE_CCMP:
 249                 case WLAN_CIPHER_SUITE_AES_CMAC:
 250                         if (params->seq_len != 6)
 251                                 return -EINVAL;
 252                         break;
 253                 }
 254         }
 255
 256         if (!cfg80211_supported_cipher_suite(&rdev->wiphy, params->cipher))
 257                 return -EINVAL;
 258
 259         return 0;
 260 }
 261
 262 unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
 263 {
 264         unsigned int hdrlen = 24;
 265
 266         if (ieee80211_is_data(fc)) {
 267                 if (ieee80211_has_a4(fc))
 268                         hdrlen = 30;
 269                 if (ieee80211_is_data_qos(fc)) {
 270                         hdrlen += IEEE80211_QOS_CTL_LEN;
 271                         if (ieee80211_has_order(fc))
 272                                 hdrlen += IEEE80211_HT_CTL_LEN;
 273                 }
 274                 goto out;
 275         }
 276
 277         if (ieee80211_is_ctl(fc)) {
 278                 /*
 279                  * ACK and CTS are 10 bytes, all others 16. To see how
 280                  * to get this condition consider
 281                  *   subtype mask:   0b0000000011110000 (0x00F0)
 282                  *   ACK subtype:    0b0000000011010000 (0x00D0)
 283                  *   CTS subtype:    0b0000000011000000 (0x00C0)
 284                  *   bits that matter:         ^^^      (0x00E0)
 285                  *   value of those: 0b0000000011000000 (0x00C0)
 286                  */
 287                 if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
 288                         hdrlen = 10;
 289                 else
 290                         hdrlen = 16;
 291         }
 292 out:
 293         return hdrlen;
 294 }
 295 EXPORT_SYMBOL(ieee80211_hdrlen);
 296
 297 unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
 298 {
 299         const struct ieee80211_hdr *hdr =
 300                         (const struct ieee80211_hdr *)skb->data;
 301         unsigned int hdrlen;
 302
 303         if (unlikely(skb->len < 10))
 304                 return 0;
 305         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 306         if (unlikely(hdrlen > skb->len))
 307                 return 0;
 308         return hdrlen;
 309 }
 310 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
 311
 312 static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
 313 {
 314         int ae = meshhdr->flags & MESH_FLAGS_AE;
 315         /* 7.1.3.5a.2 */
 316         switch (ae) {
 317         case 0:
 318                 return 6;
 319         case MESH_FLAGS_AE_A4:
 320                 return 12;
 321         case MESH_FLAGS_AE_A5_A6:
 322                 return 18;
 323         case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
 324                 return 24;
 325         default:
 326                 return 6;
 327         }
 328 }
 329
 330 int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
 331                            enum nl80211_iftype iftype)
 332 {
 333         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 334         u16 hdrlen, ethertype;
 335         u8 *payload;
 336         u8 dst[ETH_ALEN];
 337         u8 src[ETH_ALEN] __aligned(2);
 338
 339         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
 340                 return -1;
 341
 342         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 343
 344         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
 345          * header
 346          * IEEE 802.11 address fields:
 347          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
 348          *   0     0   DA    SA    BSSID n/a
 349          *   0     1   DA    BSSID SA    n/a
 350          *   1     0   BSSID SA    DA    n/a
 351          *   1     1   RA    TA    DA    SA
 352          */
 353         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
 354         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
 355
 356         switch (hdr->frame_control &
 357                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
 358         case cpu_to_le16(IEEE80211_FCTL_TODS):
 359                 if (unlikely(iftype != NL80211_IFTYPE_AP &&
 360                              iftype != NL80211_IFTYPE_AP_VLAN &&
 361                              iftype != NL80211_IFTYPE_P2P_GO))
 362                         return -1;
 363                 break;
 364         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
 365                 if (unlikely(iftype != NL80211_IFTYPE_WDS &&
 366                              iftype != NL80211_IFTYPE_MESH_POINT &&
 367                              iftype != NL80211_IFTYPE_AP_VLAN &&
 368                              iftype != NL80211_IFTYPE_STATION))
 369                         return -1;
 370                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 371                         struct ieee80211s_hdr *meshdr =
 372                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 373                         /* make sure meshdr->flags is on the linear part */
 374                         if (!pskb_may_pull(skb, hdrlen + 1))
 375                                 return -1;
 376                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
 377                                 skb_copy_bits(skb, hdrlen +
 378                                         offsetof(struct ieee80211s_hdr, eaddr1),
 379                                         dst, ETH_ALEN);
 380                                 skb_copy_bits(skb, hdrlen +
 381                                         offsetof(struct ieee80211s_hdr, eaddr2),
 382                                         src, ETH_ALEN);
 383                         }
 384                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 385                 }
 386                 break;
 387         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
 388                 if ((iftype != NL80211_IFTYPE_STATION &&
 389                      iftype != NL80211_IFTYPE_P2P_CLIENT &&
 390                      iftype != NL80211_IFTYPE_MESH_POINT) ||
 391                     (is_multicast_ether_addr(dst) &&
 392                      ether_addr_equal(src, addr)))
 393                         return -1;
 394                 if (iftype == NL80211_IFTYPE_MESH_POINT) {
 395                         struct ieee80211s_hdr *meshdr =
 396                                 (struct ieee80211s_hdr *) (skb->data + hdrlen);
 397                         /* make sure meshdr->flags is on the linear part */
 398                         if (!pskb_may_pull(skb, hdrlen + 1))
 399                                 return -1;
 400                         if (meshdr->flags & MESH_FLAGS_AE_A4)
 401                                 skb_copy_bits(skb, hdrlen +
 402                                         offsetof(struct ieee80211s_hdr, eaddr1),
 403                                         src, ETH_ALEN);
 404                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 405                 }
 406                 break;
 407         case cpu_to_le16(0):
 408                 if (iftype != NL80211_IFTYPE_ADHOC &&
 409                     iftype != NL80211_IFTYPE_STATION)
 410                                 return -1;
 411                 break;
 412         }
 413
 414         if (!pskb_may_pull(skb, hdrlen + 8))
 415                 return -1;
 416
 417         payload = skb->data + hdrlen;
 418         ethertype = (payload[6] << 8) | payload[7];
 419
 420         if (likely((ether_addr_equal(payload, rfc1042_header) &&
 421                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 422                    ether_addr_equal(payload, bridge_tunnel_header))) {
 423                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
 424                  * replace EtherType */
 425                 skb_pull(skb, hdrlen + 6);
 426                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
 427                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
 428         } else {
 429                 struct ethhdr *ehdr;
 430                 __be16 len;
 431
 432                 skb_pull(skb, hdrlen);
 433                 len = htons(skb->len);
 434                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
 435                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
 436                 memcpy(ehdr->h_source, src, ETH_ALEN);
 437                 ehdr->h_proto = len;
 438         }
 439         return 0;
 440 }
 441 EXPORT_SYMBOL(ieee80211_data_to_8023);
 442
 443 int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
 444                              enum nl80211_iftype iftype, u8 *bssid, bool qos)
 445 {
 446         struct ieee80211_hdr hdr;
 447         u16 hdrlen, ethertype;
 448         __le16 fc;
 449         const u8 *encaps_data;
 450         int encaps_len, skip_header_bytes;
 451         int nh_pos, h_pos;
 452         int head_need;
 453
 454         if (unlikely(skb->len < ETH_HLEN))
 455                 return -EINVAL;
 456
 457         nh_pos = skb_network_header(skb) - skb->data;
 458         h_pos = skb_transport_header(skb) - skb->data;
 459
 460         /* convert Ethernet header to proper 802.11 header (based on
 461          * operation mode) */
 462         ethertype = (skb->data[12] << 8) | skb->data[13];
 463         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
 464
 465         switch (iftype) {
 466         case NL80211_IFTYPE_AP:
 467         case NL80211_IFTYPE_AP_VLAN:
 468         case NL80211_IFTYPE_P2P_GO:
 469                 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 470                 /* DA BSSID SA */
 471                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 472                 memcpy(hdr.addr2, addr, ETH_ALEN);
 473                 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
 474                 hdrlen = 24;
 475                 break;
 476         case NL80211_IFTYPE_STATION:
 477         case NL80211_IFTYPE_P2P_CLIENT:
 478                 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
 479                 /* BSSID SA DA */
 480                 memcpy(hdr.addr1, bssid, ETH_ALEN);
 481                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 482                 memcpy(hdr.addr3, skb->data, ETH_ALEN);
 483                 hdrlen = 24;
 484                 break;
 485         case NL80211_IFTYPE_ADHOC:
 486                 /* DA SA BSSID */
 487                 memcpy(hdr.addr1, skb->data, ETH_ALEN);
 488                 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 489                 memcpy(hdr.addr3, bssid, ETH_ALEN);
 490                 hdrlen = 24;
 491                 break;
 492         default:
 493                 return -EOPNOTSUPP;
 494         }
 495
 496         if (qos) {
 497                 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
 498                 hdrlen += 2;
 499         }
 500
 501         hdr.frame_control = fc;
 502         hdr.duration_id = 0;
 503         hdr.seq_ctrl = 0;
 504
 505         skip_header_bytes = ETH_HLEN;
 506         if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
 507                 encaps_data = bridge_tunnel_header;
 508                 encaps_len = sizeof(bridge_tunnel_header);
 509                 skip_header_bytes -= 2;
 510         } else if (ethertype > 0x600) {
 511                 encaps_data = rfc1042_header;
 512                 encaps_len = sizeof(rfc1042_header);
 513                 skip_header_bytes -= 2;
 514         } else {
 515                 encaps_data = NULL;
 516                 encaps_len = 0;
 517         }
 518
 519         skb_pull(skb, skip_header_bytes);
 520         nh_pos -= skip_header_bytes;
 521         h_pos -= skip_header_bytes;
 522
 523         head_need = hdrlen + encaps_len - skb_headroom(skb);
 524
 525         if (head_need > 0 || skb_cloned(skb)) {
 526                 head_need = max(head_need, 0);
 527                 if (head_need)
 528                         skb_orphan(skb);
 529
 530                 if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC))
 531                         return -ENOMEM;
 532
 533                 skb->truesize += head_need;
 534         }
 535
 536         if (encaps_data) {
 537                 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
 538                 nh_pos += encaps_len;
 539                 h_pos += encaps_len;
 540         }
 541
 542         memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
 543
 544         nh_pos += hdrlen;
 545         h_pos += hdrlen;
 546
 547         /* Update skb pointers to various headers since this modified frame
 548          * is going to go through Linux networking code that may potentially
 549          * need things like pointer to IP header. */
 550         skb_set_mac_header(skb, 0);
 551         skb_set_network_header(skb, nh_pos);
 552         skb_set_transport_header(skb, h_pos);
 553
 554         return 0;
 555 }
 556 EXPORT_SYMBOL(ieee80211_data_from_8023);
 557
 558
 559 void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
 560                               const u8 *addr, enum nl80211_iftype iftype,
 561                               const unsigned int extra_headroom,
 562                               bool has_80211_header)
 563 {
 564         struct sk_buff *frame = NULL;
 565         u16 ethertype;
 566         u8 *payload;
 567         const struct ethhdr *eth;
 568         int remaining, err;
 569         u8 dst[ETH_ALEN], src[ETH_ALEN];
 570
 571         if (has_80211_header) {
 572                 err = ieee80211_data_to_8023(skb, addr, iftype);
 573                 if (err)
 574                         goto out;
 575
 576                 /* skip the wrapping header */
 577                 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
 578                 if (!eth)
 579                         goto out;
 580         } else {
 581                 eth = (struct ethhdr *) skb->data;
 582         }
 583
 584         while (skb != frame) {
 585                 u8 padding;
 586                 __be16 len = eth->h_proto;
 587                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
 588
 589                 remaining = skb->len;
 590                 memcpy(dst, eth->h_dest, ETH_ALEN);
 591                 memcpy(src, eth->h_source, ETH_ALEN);
 592
 593                 padding = (4 - subframe_len) & 0x3;
 594                 /* the last MSDU has no padding */
 595                 if (subframe_len > remaining)
 596                         goto purge;
 597
 598                 skb_pull(skb, sizeof(struct ethhdr));
 599                 /* reuse skb for the last subframe */
 600                 if (remaining <= subframe_len + padding)
 601                         frame = skb;
 602                 else {
 603                         unsigned int hlen = ALIGN(extra_headroom, 4);
 604                         /*
 605                          * Allocate and reserve two bytes more for payload
 606                          * alignment since sizeof(struct ethhdr) is 14.
 607                          */
 608                         frame = dev_alloc_skb(hlen + subframe_len + 2);
 609                         if (!frame)
 610                                 goto purge;
 611
 612                         skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
 613                         memcpy(skb_put(frame, ntohs(len)), skb->data,
 614                                 ntohs(len));
 615
 616                         eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
 617                                                         padding);
 618                         if (!eth) {
 619                                 dev_kfree_skb(frame);
 620                                 goto purge;
 621                         }
 622                 }
 623
 624                 skb_reset_network_header(frame);
 625                 frame->dev = skb->dev;
 626                 frame->priority = skb->priority;
 627
 628                 payload = frame->data;
 629                 ethertype = (payload[6] << 8) | payload[7];
 630
 631                 if (likely((ether_addr_equal(payload, rfc1042_header) &&
 632                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 633                            ether_addr_equal(payload, bridge_tunnel_header))) {
 634                         /* remove RFC1042 or Bridge-Tunnel
 635                          * encapsulation and replace EtherType */
 636                         skb_pull(frame, 6);
 637                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 638                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 639                 } else {
 640                         memcpy(skb_push(frame, sizeof(__be16)), &len,
 641                                 sizeof(__be16));
 642                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 643                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 644                 }
 645                 __skb_queue_tail(list, frame);
 646         }
 647
 648         return;
 649
 650  purge:
 651         __skb_queue_purge(list);
 652  out:
 653         dev_kfree_skb(skb);
 654 }
 655 EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
 656
 657 /* Given a data frame determine the 802.1p/1d tag to use. */
 658 unsigned int cfg80211_classify8021d(struct sk_buff *skb)
 659 {
 660         unsigned int dscp;
 661
 662         /* skb->priority values from 256->263 are magic values to
 663          * directly indicate a specific 802.1d priority.  This is used
 664          * to allow 802.1d priority to be passed directly in from VLAN
 665          * tags, etc.
 666          */
 667         if (skb->priority >= 256 && skb->priority <= 263)
 668                 return skb->priority - 256;
 669
 670         switch (skb->protocol) {
 671         case htons(ETH_P_IP):
 672                 dscp = ipv4_get_dsfield(ip_hdr(skb)) & 0xfc;
 673                 break;
 674         case htons(ETH_P_IPV6):
 675                 dscp = ipv6_get_dsfield(ipv6_hdr(skb)) & 0xfc;
 676                 break;
 677         default:
 678                 return 0;
 679         }
 680
 681         return dscp >> 5;
 682 }
 683 EXPORT_SYMBOL(cfg80211_classify8021d);
 684
 685 const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
 686 {
 687         u8 *end, *pos;
 688
 689         pos = bss->information_elements;
 690         if (pos == NULL)
 691                 return NULL;
 692         end = pos + bss->len_information_elements;
 693
 694         while (pos + 1 < end) {
 695                 if (pos + 2 + pos[1] > end)
 696                         break;
 697                 if (pos[0] == ie)
 698                         return pos;
 699                 pos += 2 + pos[1];
 700         }
 701
 702         return NULL;
 703 }
 704 EXPORT_SYMBOL(ieee80211_bss_get_ie);
 705
 706 void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
 707 {
 708         struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
 709         struct net_device *dev = wdev->netdev;
 710         int i;
 711
 712         if (!wdev->connect_keys)
 713                 return;
 714
 715         for (i = 0; i < 6; i++) {
 716                 if (!wdev->connect_keys->params[i].cipher)
 717                         continue;
 718                 if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
 719                                         &wdev->connect_keys->params[i])) {
 720                         netdev_err(dev, "failed to set key %d\n", i);
 721                         continue;
 722                 }
 723                 if (wdev->connect_keys->def == i)
 724                         if (rdev->ops->set_default_key(wdev->wiphy, dev,
 725                                                        i, true, true)) {
 726                                 netdev_err(dev, "failed to set defkey %d\n", i);
 727                                 continue;
 728                         }
 729                 if (wdev->connect_keys->defmgmt == i)
 730                         if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
 731                                 netdev_err(dev, "failed to set mgtdef %d\n", i);
 732         }
 733
 734         kfree(wdev->connect_keys);
 735         wdev->connect_keys = NULL;
 736 }
 737
 738 static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
 739 {
 740         struct cfg80211_event *ev;
 741         unsigned long flags;
 742         const u8 *bssid = NULL;
 743
 744         spin_lock_irqsave(&wdev->event_lock, flags);
 745         while (!list_empty(&wdev->event_list)) {
 746                 ev = list_first_entry(&wdev->event_list,
 747                                       struct cfg80211_event, list);
 748                 list_del(&ev->list);
 749                 spin_unlock_irqrestore(&wdev->event_lock, flags);
 750
 751                 wdev_lock(wdev);
 752                 switch (ev->type) {
 753                 case EVENT_CONNECT_RESULT:
 754                         if (!is_zero_ether_addr(ev->cr.bssid))
 755                                 bssid = ev->cr.bssid;
 756                         __cfg80211_connect_result(
 757                                 wdev->netdev, bssid,
 758                                 ev->cr.req_ie, ev->cr.req_ie_len,
 759                                 ev->cr.resp_ie, ev->cr.resp_ie_len,
 760                                 ev->cr.status,
 761                                 ev->cr.status == WLAN_STATUS_SUCCESS,
 762                                 NULL);
 763                         break;
 764                 case EVENT_ROAMED:
 765                         __cfg80211_roamed(wdev, ev->rm.bss, ev->rm.req_ie,
 766                                           ev->rm.req_ie_len, ev->rm.resp_ie,
 767                                           ev->rm.resp_ie_len);
 768                         break;
 769                 case EVENT_DISCONNECTED:
 770                         __cfg80211_disconnected(wdev->netdev,
 771                                                 ev->dc.ie, ev->dc.ie_len,
 772                                                 ev->dc.reason, true);
 773                         break;
 774                 case EVENT_IBSS_JOINED:
 775                         __cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
 776                         break;
 777                 }
 778                 wdev_unlock(wdev);
 779
 780                 kfree(ev);
 781
 782                 spin_lock_irqsave(&wdev->event_lock, flags);
 783         }
 784         spin_unlock_irqrestore(&wdev->event_lock, flags);
 785 }
 786
 787 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
 788 {
 789         struct wireless_dev *wdev;
 790
 791         ASSERT_RTNL();
 792         ASSERT_RDEV_LOCK(rdev);
 793
 794         mutex_lock(&rdev->devlist_mtx);
 795
 796         list_for_each_entry(wdev, &rdev->wdev_list, list)
 797                 cfg80211_process_wdev_events(wdev);
 798
 799         mutex_unlock(&rdev->devlist_mtx);
 800 }
 801
 802 int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 803                           struct net_device *dev, enum nl80211_iftype ntype,
 804                           u32 *flags, struct vif_params *params)
 805 {
 806         int err;
 807         enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
 808
 809         ASSERT_RDEV_LOCK(rdev);
 810
 811         /* don't support changing VLANs, you just re-create them */
 812         if (otype == NL80211_IFTYPE_AP_VLAN)
 813                 return -EOPNOTSUPP;
 814
 815         if (!rdev->ops->change_virtual_intf ||
 816             !(rdev->wiphy.interface_modes & (1 << ntype)))
 817                 return -EOPNOTSUPP;
 818
 819         /* if it's part of a bridge, reject changing type to station/ibss */
 820         if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
 821             (ntype == NL80211_IFTYPE_ADHOC ||
 822              ntype == NL80211_IFTYPE_STATION ||
 823              ntype == NL80211_IFTYPE_P2P_CLIENT))
 824                 return -EBUSY;
 825
 826         if (ntype != otype && netif_running(dev)) {
 827                 mutex_lock(&rdev->devlist_mtx);
 828                 err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
 829                                                     ntype);
 830                 mutex_unlock(&rdev->devlist_mtx);
 831                 if (err)
 832                         return err;
 833
 834                 dev->ieee80211_ptr->use_4addr = false;
 835                 dev->ieee80211_ptr->mesh_id_up_len = 0;
 836
 837                 switch (otype) {
 838                 case NL80211_IFTYPE_AP:
 839                         cfg80211_stop_ap(rdev, dev);
 840                         break;
 841                 case NL80211_IFTYPE_ADHOC:
 842                         cfg80211_leave_ibss(rdev, dev, false);
 843                         break;
 844                 case NL80211_IFTYPE_STATION:
 845                 case NL80211_IFTYPE_P2P_CLIENT:
 846                         cfg80211_disconnect(rdev, dev,
 847                                             WLAN_REASON_DEAUTH_LEAVING, true);
 848                         break;
 849                 case NL80211_IFTYPE_MESH_POINT:
 850                         /* mesh should be handled? */
 851                         break;
 852                 default:
 853                         break;
 854                 }
 855
 856                 cfg80211_process_rdev_events(rdev);
 857         }
 858
 859         err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
 860                                              ntype, flags, params);
 861
 862         WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
 863
 864         if (!err && params && params->use_4addr != -1)
 865                 dev->ieee80211_ptr->use_4addr = params->use_4addr;
 866
 867         if (!err) {
 868                 dev->priv_flags &= ~IFF_DONT_BRIDGE;
 869                 switch (ntype) {
 870                 case NL80211_IFTYPE_STATION:
 871                         if (dev->ieee80211_ptr->use_4addr)
 872                                 break;
 873                         /* fall through */
 874                 case NL80211_IFTYPE_P2P_CLIENT:
 875                 case NL80211_IFTYPE_ADHOC:
 876                         dev->priv_flags |= IFF_DONT_BRIDGE;
 877                         break;
 878                 case NL80211_IFTYPE_P2P_GO:
 879                 case NL80211_IFTYPE_AP:
 880                 case NL80211_IFTYPE_AP_VLAN:
 881                 case NL80211_IFTYPE_WDS:
 882                 case NL80211_IFTYPE_MESH_POINT:
 883                         /* bridging OK */
 884                         break;
 885                 case NL80211_IFTYPE_MONITOR:
 886                         /* monitor can't bridge anyway */
 887                         break;
 888                 case NL80211_IFTYPE_UNSPECIFIED:
 889                 case NUM_NL80211_IFTYPES:
 890                         /* not happening */
 891                         break;
 892                 }
 893         }
 894
 895         if (!err && ntype != otype && netif_running(dev)) {
 896                 cfg80211_update_iface_num(rdev, ntype, 1);
 897                 cfg80211_update_iface_num(rdev, otype, -1);
 898         }
 899
 900         return err;
 901 }
 902
 903 static u32 cfg80211_calculate_bitrate_60g(struct rate_info *rate)
 904 {
 905         static const u32 __mcs2bitrate[] = {
 906                 /* control PHY */
 907                 [0] =   275,
 908                 /* SC PHY */
 909                 [1] =  3850,
 910                 [2] =  7700,
 911                 [3] =  9625,
 912                 [4] = 11550,
 913                 [5] = 12512, /* 1251.25 mbps */
 914                 [6] = 15400,
 915                 [7] = 19250,
 916                 [8] = 23100,
 917                 [9] = 25025,
 918                 [10] = 30800,
 919                 [11] = 38500,
 920                 [12] = 46200,
 921                 /* OFDM PHY */
 922                 [13] =  6930,
 923                 [14] =  8662, /* 866.25 mbps */
 924                 [15] = 13860,
 925                 [16] = 17325,
 926                 [17] = 20790,
 927                 [18] = 27720,
 928                 [19] = 34650,
 929                 [20] = 41580,
 930                 [21] = 45045,
 931                 [22] = 51975,
 932                 [23] = 62370,
 933                 [24] = 67568, /* 6756.75 mbps */
 934                 /* LP-SC PHY */
 935                 [25] =  6260,
 936                 [26] =  8340,
 937                 [27] = 11120,
 938                 [28] = 12510,
 939                 [29] = 16680,
 940                 [30] = 22240,
 941                 [31] = 25030,
 942         };
 943
 944         if (WARN_ON_ONCE(rate->mcs >= ARRAY_SIZE(__mcs2bitrate)))
 945                 return 0;
 946
 947         return __mcs2bitrate[rate->mcs];
 948 }
 949
 950 u32 cfg80211_calculate_bitrate(struct rate_info *rate)
 951 {
 952         int modulation, streams, bitrate;
 953
 954         if (!(rate->flags & RATE_INFO_FLAGS_MCS))
 955                 return rate->legacy;
 956         if (rate->flags & RATE_INFO_FLAGS_60G)
 957                 return cfg80211_calculate_bitrate_60g(rate);
 958
 959         /* the formula below does only work for MCS values smaller than 32 */
 960         if (WARN_ON_ONCE(rate->mcs >= 32))
 961                 return 0;
 962
 963         modulation = rate->mcs & 7;
 964         streams = (rate->mcs >> 3) + 1;
 965
 966         bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
 967                         13500000 : 6500000;
 968
 969         if (modulation < 4)
 970                 bitrate *= (modulation + 1);
 971         else if (modulation == 4)
 972                 bitrate *= (modulation + 2);
 973         else
 974                 bitrate *= (modulation + 3);
 975
 976         bitrate *= streams;
 977
 978         if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
 979                 bitrate = (bitrate / 9) * 10;
 980
 981         /* do NOT round down here */
 982         return (bitrate + 50000) / 100000;
 983 }
 984 EXPORT_SYMBOL(cfg80211_calculate_bitrate);
 985
 986 int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
 987                                  u32 beacon_int)
 988 {
 989         struct wireless_dev *wdev;
 990         int res = 0;
 991
 992         if (!beacon_int)
 993                 return -EINVAL;
 994
 995         mutex_lock(&rdev->devlist_mtx);
 996
 997         list_for_each_entry(wdev, &rdev->wdev_list, list) {
 998                 if (!wdev->beacon_interval)
 999                         continue;
1000                 if (wdev->beacon_interval != beacon_int) {
1001                         res = -EINVAL;
1002                         break;
1003                 }
1004         }
1005
1006         mutex_unlock(&rdev->devlist_mtx);
1007
1008         return res;
1009 }
1010
1011 int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
1012                                  struct wireless_dev *wdev,
1013                                  enum nl80211_iftype iftype,
1014                                  struct ieee80211_channel *chan,
1015                                  enum cfg80211_chan_mode chanmode)
1016 {
1017         struct wireless_dev *wdev_iter;
1018         u32 used_iftypes = BIT(iftype);
1019         int num[NUM_NL80211_IFTYPES];
1020         struct ieee80211_channel
1021                         *used_channels[CFG80211_MAX_NUM_DIFFERENT_CHANNELS];
1022         struct ieee80211_channel *ch;
1023         enum cfg80211_chan_mode chmode;
1024         int num_different_channels = 0;
1025         int total = 1;
1026         int i, j;
1027
1028         ASSERT_RTNL();
1029         lockdep_assert_held(&rdev->devlist_mtx);
1030
1031         /* Always allow software iftypes */
1032         if (rdev->wiphy.software_iftypes & BIT(iftype))
1033                 return 0;
1034
1035         memset(num, 0, sizeof(num));
1036         memset(used_channels, 0, sizeof(used_channels));
1037
1038         num[iftype] = 1;
1039
1040         switch (chanmode) {
1041         case CHAN_MODE_UNDEFINED:
1042                 break;
1043         case CHAN_MODE_SHARED:
1044                 WARN_ON(!chan);
1045                 used_channels[0] = chan;
1046                 num_different_channels++;
1047                 break;
1048         case CHAN_MODE_EXCLUSIVE:
1049                 num_different_channels++;
1050                 break;
1051         }
1052
1053         list_for_each_entry(wdev_iter, &rdev->wdev_list, list) {
1054                 if (wdev_iter == wdev)
1055                         continue;
1056                 if (!netif_running(wdev_iter->netdev))
1057                         continue;
1058
1059                 if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))
1060                         continue;
1061
1062                 /*
1063                  * We may be holding the "wdev" mutex, but now need to lock
1064                  * wdev_iter. This is OK because once we get here wdev_iter
1065                  * is not wdev (tested above), but we need to use the nested
1066                  * locking for lockdep.
1067                  */
1068                 mutex_lock_nested(&wdev_iter->mtx, 1);
1069                 __acquire(wdev_iter->mtx);
1070                 cfg80211_get_chan_state(wdev_iter, &ch, &chmode);
1071                 wdev_unlock(wdev_iter);
1072
1073                 switch (chmode) {
1074                 case CHAN_MODE_UNDEFINED:
1075                         break;
1076                 case CHAN_MODE_SHARED:
1077                         for (i = 0; i < CFG80211_MAX_NUM_DIFFERENT_CHANNELS; i++)
1078                                 if (!used_channels[i] || used_channels[i] == ch)
1079                                         break;
1080
1081                         if (i == CFG80211_MAX_NUM_DIFFERENT_CHANNELS)
1082                                 return -EBUSY;
1083
1084                         if (used_channels[i] == NULL) {
1085                                 used_channels[i] = ch;
1086                                 num_different_channels++;
1087                         }
1088                         break;
1089                 case CHAN_MODE_EXCLUSIVE:
1090                         num_different_channels++;
1091                         break;
1092                 }
1093
1094                 num[wdev_iter->iftype]++;
1095                 total++;
1096                 used_iftypes |= BIT(wdev_iter->iftype);
1097         }
1098
1099         if (total == 1)
1100                 return 0;
1101
1102         for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) {
1103                 const struct ieee80211_iface_combination *c;
1104                 struct ieee80211_iface_limit *limits;
1105                 u32 all_iftypes = 0;
1106
1107                 c = &rdev->wiphy.iface_combinations[i];
1108
1109                 if (total > c->max_interfaces)
1110                         continue;
1111                 if (num_different_channels > c->num_different_channels)
1112                         continue;
1113
1114                 limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
1115                                  GFP_KERNEL);
1116                 if (!limits)
1117                         return -ENOMEM;
1118
1119                 for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
1120                         if (rdev->wiphy.software_iftypes & BIT(iftype))
1121                                 continue;
1122                         for (j = 0; j < c->n_limits; j++) {
1123                                 all_iftypes |= limits[j].types;
1124                                 if (!(limits[j].types & BIT(iftype)))
1125                                         continue;
1126                                 if (limits[j].max < num[iftype])
1127                                         goto cont;
1128                                 limits[j].max -= num[iftype];
1129                         }
1130                 }
1131
1132                 /*
1133                  * Finally check that all iftypes that we're currently
1134                  * using are actually part of this combination. If they
1135                  * aren't then we can't use this combination and have
1136                  * to continue to the next.
1137                  */
1138                 if ((all_iftypes & used_iftypes) != used_iftypes)
1139                         goto cont;
1140
1141                 /*
1142                  * This combination covered all interface types and
1143                  * supported the requested numbers, so we're good.
1144                  */
1145                 kfree(limits);
1146                 return 0;
1147  cont:
1148                 kfree(limits);
1149         }
1150
1151         return -EBUSY;
1152 }
1153
1154 int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
1155                            const u8 *rates, unsigned int n_rates,
1156                            u32 *mask)
1157 {
1158         int i, j;
1159
1160         if (!sband)
1161                 return -EINVAL;
1162
1163         if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
1164                 return -EINVAL;
1165
1166         *mask = 0;
1167
1168         for (i = 0; i < n_rates; i++) {
1169                 int rate = (rates[i] & 0x7f) * 5;
1170                 bool found = false;
1171
1172                 for (j = 0; j < sband->n_bitrates; j++) {
1173                         if (sband->bitrates[j].bitrate == rate) {
1174                                 found = true;
1175                                 *mask |= BIT(j);
1176                                 break;
1177                         }
1178                 }
1179                 if (!found)
1180                         return -EINVAL;
1181         }
1182
1183         /*
1184          * mask must have at least one bit set here since we
1185          * didn't accept a 0-length rates array nor allowed
1186          * entries in the array that didn't exist
1187          */
1188
1189         return 0;
1190 }
1191
1192 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
1193 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
1194 const unsigned char rfc1042_header[] __aligned(2) =
1195         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
1196 EXPORT_SYMBOL(rfc1042_header);
1197
1198 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
1199 const unsigned char bridge_tunnel_header[] __aligned(2) =
1200         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
1201 EXPORT_SYMBOL(bridge_tunnel_header);