net/wireless/util.c

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