src/common/ieee802_11_common.c

   1 /*
   2  * IEEE 802.11 Common routines
   3  * Copyright (c) 2002-2013, Jouni Malinen <j@w1.fi>
   4  *
   5  * This software may be distributed under the terms of the BSD license.
   6  * See README for more details.
   7  */
   8
   9 #include "includes.h"
  10
  11 #include "common.h"
  12 #include "defs.h"
  13 #include "ieee802_11_defs.h"
  14 #include "ieee802_11_common.h"
  15
  16
  17 static int ieee802_11_parse_vendor_specific(const u8 *pos, size_t elen,
  18                                             struct ieee802_11_elems *elems,
  19                                             int show_errors)
  20 {
  21         unsigned int oui;
  22
  23         /* first 3 bytes in vendor specific information element are the IEEE
  24          * OUI of the vendor. The following byte is used a vendor specific
  25          * sub-type. */
  26         if (elen < 4) {
  27                 if (show_errors) {
  28                         wpa_printf(MSG_MSGDUMP, "short vendor specific "
  29                                    "information element ignored (len=%lu)",
  30                                    (unsigned long) elen);
  31                 }
  32                 return -1;
  33         }
  34
  35         oui = WPA_GET_BE24(pos);
  36         switch (oui) {
  37         case OUI_MICROSOFT:
  38                 /* Microsoft/Wi-Fi information elements are further typed and
  39                  * subtyped */
  40                 switch (pos[3]) {
  41                 case 1:
  42                         /* Microsoft OUI (00:50:F2) with OUI Type 1:
  43                          * real WPA information element */
  44                         elems->wpa_ie = pos;
  45                         elems->wpa_ie_len = elen;
  46                         break;
  47                 case WMM_OUI_TYPE:
  48                         /* WMM information element */
  49                         if (elen < 5) {
  50                                 wpa_printf(MSG_MSGDUMP, "short WMM "
  51                                            "information element ignored "
  52                                            "(len=%lu)",
  53                                            (unsigned long) elen);
  54                                 return -1;
  55                         }
  56                         switch (pos[4]) {
  57                         case WMM_OUI_SUBTYPE_INFORMATION_ELEMENT:
  58                         case WMM_OUI_SUBTYPE_PARAMETER_ELEMENT:
  59                                 /*
  60                                  * Share same pointer since only one of these
  61                                  * is used and they start with same data.
  62                                  * Length field can be used to distinguish the
  63                                  * IEs.
  64                                  */
  65                                 elems->wmm = pos;
  66                                 elems->wmm_len = elen;
  67                                 break;
  68                         case WMM_OUI_SUBTYPE_TSPEC_ELEMENT:
  69                                 elems->wmm_tspec = pos;
  70                                 elems->wmm_tspec_len = elen;
  71                                 break;
  72                         default:
  73                                 wpa_printf(MSG_EXCESSIVE, "unknown WMM "
  74                                            "information element ignored "
  75                                            "(subtype=%d len=%lu)",
  76                                            pos[4], (unsigned long) elen);
  77                                 return -1;
  78                         }
  79                         break;
  80                 case 4:
  81                         /* Wi-Fi Protected Setup (WPS) IE */
  82                         elems->wps_ie = pos;
  83                         elems->wps_ie_len = elen;
  84                         break;
  85                 default:
  86                         wpa_printf(MSG_EXCESSIVE, "Unknown Microsoft "
  87                                    "information element ignored "
  88                                    "(type=%d len=%lu)",
  89                                    pos[3], (unsigned long) elen);
  90                         return -1;
  91                 }
  92                 break;
  93
  94         case OUI_WFA:
  95                 switch (pos[3]) {
  96                 case P2P_OUI_TYPE:
  97                         /* Wi-Fi Alliance - P2P IE */
  98                         elems->p2p = pos;
  99                         elems->p2p_len = elen;
 100                         break;
 101                 case WFD_OUI_TYPE:
 102                         /* Wi-Fi Alliance - WFD IE */
 103                         elems->wfd = pos;
 104                         elems->wfd_len = elen;
 105                         break;
 106                 case HS20_INDICATION_OUI_TYPE:
 107                         /* Hotspot 2.0 */
 108                         elems->hs20 = pos;
 109                         elems->hs20_len = elen;
 110                         break;
 111                 default:
 112                         wpa_printf(MSG_MSGDUMP, "Unknown WFA "
 113                                    "information element ignored "
 114                                    "(type=%d len=%lu)\n",
 115                                    pos[3], (unsigned long) elen);
 116                         return -1;
 117                 }
 118                 break;
 119
 120         case OUI_BROADCOM:
 121                 switch (pos[3]) {
 122                 case VENDOR_HT_CAPAB_OUI_TYPE:
 123                         elems->vendor_ht_cap = pos;
 124                         elems->vendor_ht_cap_len = elen;
 125                         break;
 126                 default:
 127                         wpa_printf(MSG_EXCESSIVE, "Unknown Broadcom "
 128                                    "information element ignored "
 129                                    "(type=%d len=%lu)",
 130                                    pos[3], (unsigned long) elen);
 131                         return -1;
 132                 }
 133                 break;
 134
 135         default:
 136                 wpa_printf(MSG_EXCESSIVE, "unknown vendor specific "
 137                            "information element ignored (vendor OUI "
 138                            "%02x:%02x:%02x len=%lu)",
 139                            pos[0], pos[1], pos[2], (unsigned long) elen);
 140                 return -1;
 141         }
 142
 143         return 0;
 144 }
 145
 146
 147 /**
 148  * ieee802_11_parse_elems - Parse information elements in management frames
 149  * @start: Pointer to the start of IEs
 150  * @len: Length of IE buffer in octets
 151  * @elems: Data structure for parsed elements
 152  * @show_errors: Whether to show parsing errors in debug log
 153  * Returns: Parsing result
 154  */
 155 ParseRes ieee802_11_parse_elems(const u8 *start, size_t len,
 156                                 struct ieee802_11_elems *elems,
 157                                 int show_errors)
 158 {
 159         size_t left = len;
 160         const u8 *pos = start;
 161         int unknown = 0;
 162
 163         os_memset(elems, 0, sizeof(*elems));
 164
 165         while (left >= 2) {
 166                 u8 id, elen;
 167
 168                 id = *pos++;
 169                 elen = *pos++;
 170                 left -= 2;
 171
 172                 if (elen > left) {
 173                         if (show_errors) {
 174                                 wpa_printf(MSG_DEBUG, "IEEE 802.11 element "
 175                                            "parse failed (id=%d elen=%d "
 176                                            "left=%lu)",
 177                                            id, elen, (unsigned long) left);
 178                                 wpa_hexdump(MSG_MSGDUMP, "IEs", start, len);
 179                         }
 180                         return ParseFailed;
 181                 }
 182
 183                 switch (id) {
 184                 case WLAN_EID_SSID:
 185                         elems->ssid = pos;
 186                         elems->ssid_len = elen;
 187                         break;
 188                 case WLAN_EID_SUPP_RATES:
 189                         elems->supp_rates = pos;
 190                         elems->supp_rates_len = elen;
 191                         break;
 192                 case WLAN_EID_FH_PARAMS:
 193                         elems->fh_params = pos;
 194                         elems->fh_params_len = elen;
 195                         break;
 196                 case WLAN_EID_DS_PARAMS:
 197                         elems->ds_params = pos;
 198                         elems->ds_params_len = elen;
 199                         break;
 200                 case WLAN_EID_CF_PARAMS:
 201                         elems->cf_params = pos;
 202                         elems->cf_params_len = elen;
 203                         break;
 204                 case WLAN_EID_TIM:
 205                         elems->tim = pos;
 206                         elems->tim_len = elen;
 207                         break;
 208                 case WLAN_EID_IBSS_PARAMS:
 209                         elems->ibss_params = pos;
 210                         elems->ibss_params_len = elen;
 211                         break;
 212                 case WLAN_EID_CHALLENGE:
 213                         elems->challenge = pos;
 214                         elems->challenge_len = elen;
 215                         break;
 216                 case WLAN_EID_ERP_INFO:
 217                         elems->erp_info = pos;
 218                         elems->erp_info_len = elen;
 219                         break;
 220                 case WLAN_EID_EXT_SUPP_RATES:
 221                         elems->ext_supp_rates = pos;
 222                         elems->ext_supp_rates_len = elen;
 223                         break;
 224                 case WLAN_EID_VENDOR_SPECIFIC:
 225                         if (ieee802_11_parse_vendor_specific(pos, elen,
 226                                                              elems,
 227                                                              show_errors))
 228                                 unknown++;
 229                         break;
 230                 case WLAN_EID_RSN:
 231                         elems->rsn_ie = pos;
 232                         elems->rsn_ie_len = elen;
 233                         break;
 234                 case WLAN_EID_PWR_CAPABILITY:
 235                         elems->power_cap = pos;
 236                         elems->power_cap_len = elen;
 237                         break;
 238                 case WLAN_EID_SUPPORTED_CHANNELS:
 239                         elems->supp_channels = pos;
 240                         elems->supp_channels_len = elen;
 241                         break;
 242                 case WLAN_EID_MOBILITY_DOMAIN:
 243                         elems->mdie = pos;
 244                         elems->mdie_len = elen;
 245                         break;
 246                 case WLAN_EID_FAST_BSS_TRANSITION:
 247                         elems->ftie = pos;
 248                         elems->ftie_len = elen;
 249                         break;
 250                 case WLAN_EID_TIMEOUT_INTERVAL:
 251                         elems->timeout_int = pos;
 252                         elems->timeout_int_len = elen;
 253                         break;
 254                 case WLAN_EID_HT_CAP:
 255                         elems->ht_capabilities = pos;
 256                         elems->ht_capabilities_len = elen;
 257                         break;
 258                 case WLAN_EID_HT_OPERATION:
 259                         elems->ht_operation = pos;
 260                         elems->ht_operation_len = elen;
 261                         break;
 262                 case WLAN_EID_VHT_CAP:
 263                         elems->vht_capabilities = pos;
 264                         elems->vht_capabilities_len = elen;
 265                         break;
 266                 case WLAN_EID_VHT_OPERATION:
 267                         elems->vht_operation = pos;
 268                         elems->vht_operation_len = elen;
 269                         break;
 270                 case WLAN_EID_LINK_ID:
 271                         if (elen < 18)
 272                                 break;
 273                         elems->link_id = pos;
 274                         break;
 275                 case WLAN_EID_INTERWORKING:
 276                         elems->interworking = pos;
 277                         elems->interworking_len = elen;
 278                         break;
 279                 case WLAN_EID_EXT_CAPAB:
 280                         elems->ext_capab = pos;
 281                         elems->ext_capab_len = elen;
 282                         break;
 283                 case WLAN_EID_BSS_MAX_IDLE_PERIOD:
 284                         if (elen < 3)
 285                                 break;
 286                         elems->bss_max_idle_period = pos;
 287                         break;
 288                 case WLAN_EID_SSID_LIST:
 289                         elems->ssid_list = pos;
 290                         elems->ssid_list_len = elen;
 291                         break;
 292                 default:
 293                         unknown++;
 294                         if (!show_errors)
 295                                 break;
 296                         wpa_printf(MSG_MSGDUMP, "IEEE 802.11 element parse "
 297                                    "ignored unknown element (id=%d elen=%d)",
 298                                    id, elen);
 299                         break;
 300                 }
 301
 302                 left -= elen;
 303                 pos += elen;
 304         }
 305
 306         if (left)
 307                 return ParseFailed;
 308
 309         return unknown ? ParseUnknown : ParseOK;
 310 }
 311
 312
 313 int ieee802_11_ie_count(const u8 *ies, size_t ies_len)
 314 {
 315         int count = 0;
 316         const u8 *pos, *end;
 317
 318         if (ies == NULL)
 319                 return 0;
 320
 321         pos = ies;
 322         end = ies + ies_len;
 323
 324         while (pos + 2 <= end) {
 325                 if (pos + 2 + pos[1] > end)
 326                         break;
 327                 count++;
 328                 pos += 2 + pos[1];
 329         }
 330
 331         return count;
 332 }
 333
 334
 335 struct wpabuf * ieee802_11_vendor_ie_concat(const u8 *ies, size_t ies_len,
 336                                             u32 oui_type)
 337 {
 338         struct wpabuf *buf;
 339         const u8 *end, *pos, *ie;
 340
 341         pos = ies;
 342         end = ies + ies_len;
 343         ie = NULL;
 344
 345         while (pos + 1 < end) {
 346                 if (pos + 2 + pos[1] > end)
 347                         return NULL;
 348                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 349                     WPA_GET_BE32(&pos[2]) == oui_type) {
 350                         ie = pos;
 351                         break;
 352                 }
 353                 pos += 2 + pos[1];
 354         }
 355
 356         if (ie == NULL)
 357                 return NULL; /* No specified vendor IE found */
 358
 359         buf = wpabuf_alloc(ies_len);
 360         if (buf == NULL)
 361                 return NULL;
 362
 363         /*
 364          * There may be multiple vendor IEs in the message, so need to
 365          * concatenate their data fields.
 366          */
 367         while (pos + 1 < end) {
 368                 if (pos + 2 + pos[1] > end)
 369                         break;
 370                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 371                     WPA_GET_BE32(&pos[2]) == oui_type)
 372                         wpabuf_put_data(buf, pos + 6, pos[1] - 4);
 373                 pos += 2 + pos[1];
 374         }
 375
 376         return buf;
 377 }
 378
 379
 380 const u8 * get_hdr_bssid(const struct ieee80211_hdr *hdr, size_t len)
 381 {
 382         u16 fc, type, stype;
 383
 384         /*
 385          * PS-Poll frames are 16 bytes. All other frames are
 386          * 24 bytes or longer.
 387          */
 388         if (len < 16)
 389                 return NULL;
 390
 391         fc = le_to_host16(hdr->frame_control);
 392         type = WLAN_FC_GET_TYPE(fc);
 393         stype = WLAN_FC_GET_STYPE(fc);
 394
 395         switch (type) {
 396         case WLAN_FC_TYPE_DATA:
 397                 if (len < 24)
 398                         return NULL;
 399                 switch (fc & (WLAN_FC_FROMDS | WLAN_FC_TODS)) {
 400                 case WLAN_FC_FROMDS | WLAN_FC_TODS:
 401                 case WLAN_FC_TODS:
 402                         return hdr->addr1;
 403                 case WLAN_FC_FROMDS:
 404                         return hdr->addr2;
 405                 default:
 406                         return NULL;
 407                 }
 408         case WLAN_FC_TYPE_CTRL:
 409                 if (stype != WLAN_FC_STYPE_PSPOLL)
 410                         return NULL;
 411                 return hdr->addr1;
 412         case WLAN_FC_TYPE_MGMT:
 413                 return hdr->addr3;
 414         default:
 415                 return NULL;
 416         }
 417 }
 418
 419
 420 int hostapd_config_wmm_ac(struct hostapd_wmm_ac_params wmm_ac_params[],
 421                           const char *name, const char *val)
 422 {
 423         int num, v;
 424         const char *pos;
 425         struct hostapd_wmm_ac_params *ac;
 426
 427         /* skip 'wme_ac_' or 'wmm_ac_' prefix */
 428         pos = name + 7;
 429         if (os_strncmp(pos, "be_", 3) == 0) {
 430                 num = 0;
 431                 pos += 3;
 432         } else if (os_strncmp(pos, "bk_", 3) == 0) {
 433                 num = 1;
 434                 pos += 3;
 435         } else if (os_strncmp(pos, "vi_", 3) == 0) {
 436                 num = 2;
 437                 pos += 3;
 438         } else if (os_strncmp(pos, "vo_", 3) == 0) {
 439                 num = 3;
 440                 pos += 3;
 441         } else {
 442                 wpa_printf(MSG_ERROR, "Unknown WMM name '%s'", pos);
 443                 return -1;
 444         }
 445
 446         ac = &wmm_ac_params[num];
 447
 448         if (os_strcmp(pos, "aifs") == 0) {
 449                 v = atoi(val);
 450                 if (v < 1 || v > 255) {
 451                         wpa_printf(MSG_ERROR, "Invalid AIFS value %d", v);
 452                         return -1;
 453                 }
 454                 ac->aifs = v;
 455         } else if (os_strcmp(pos, "cwmin") == 0) {
 456                 v = atoi(val);
 457                 if (v < 0 || v > 12) {
 458                         wpa_printf(MSG_ERROR, "Invalid cwMin value %d", v);
 459                         return -1;
 460                 }
 461                 ac->cwmin = v;
 462         } else if (os_strcmp(pos, "cwmax") == 0) {
 463                 v = atoi(val);
 464                 if (v < 0 || v > 12) {
 465                         wpa_printf(MSG_ERROR, "Invalid cwMax value %d", v);
 466                         return -1;
 467                 }
 468                 ac->cwmax = v;
 469         } else if (os_strcmp(pos, "txop_limit") == 0) {
 470                 v = atoi(val);
 471                 if (v < 0 || v > 0xffff) {
 472                         wpa_printf(MSG_ERROR, "Invalid txop value %d", v);
 473                         return -1;
 474                 }
 475                 ac->txop_limit = v;
 476         } else if (os_strcmp(pos, "acm") == 0) {
 477                 v = atoi(val);
 478                 if (v < 0 || v > 1) {
 479                         wpa_printf(MSG_ERROR, "Invalid acm value %d", v);
 480                         return -1;
 481                 }
 482                 ac->admission_control_mandatory = v;
 483         } else {
 484                 wpa_printf(MSG_ERROR, "Unknown wmm_ac_ field '%s'", pos);
 485                 return -1;
 486         }
 487
 488         return 0;
 489 }
 490
 491
 492 enum hostapd_hw_mode ieee80211_freq_to_chan(int freq, u8 *channel)
 493 {
 494         enum hostapd_hw_mode mode = NUM_HOSTAPD_MODES;
 495
 496         if (freq >= 2412 && freq <= 2472) {
 497                 mode = HOSTAPD_MODE_IEEE80211G;
 498                 *channel = (freq - 2407) / 5;
 499         } else if (freq == 2484) {
 500                 mode = HOSTAPD_MODE_IEEE80211B;
 501                 *channel = 14;
 502         } else if (freq >= 4900 && freq < 5000) {
 503                 mode = HOSTAPD_MODE_IEEE80211A;
 504                 *channel = (freq - 4000) / 5;
 505         } else if (freq >= 5000 && freq < 5900) {
 506                 mode = HOSTAPD_MODE_IEEE80211A;
 507                 *channel = (freq - 5000) / 5;
 508         } else if (freq >= 56160 + 2160 * 1 && freq <= 56160 + 2160 * 4) {
 509                 mode = HOSTAPD_MODE_IEEE80211AD;
 510                 *channel = (freq - 56160) / 2160;
 511         }
 512
 513         return mode;
 514 }