src/common/ieee802_11_common.c

   1 /*
   2  * IEEE 802.11 Common routines
   3  * Copyright (c) 2002-2012, 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 "ieee802_11_defs.h"
  13 #include "ieee802_11_common.h"
  14
  15
  16 static int ieee802_11_parse_vendor_specific(const u8 *pos, size_t elen,
  17                                             struct ieee802_11_elems *elems,
  18                                             int show_errors)
  19 {
  20         unsigned int oui;
  21
  22         /* first 3 bytes in vendor specific information element are the IEEE
  23          * OUI of the vendor. The following byte is used a vendor specific
  24          * sub-type. */
  25         if (elen < 4) {
  26                 if (show_errors) {
  27                         wpa_printf(MSG_MSGDUMP, "short vendor specific "
  28                                    "information element ignored (len=%lu)",
  29                                    (unsigned long) elen);
  30                 }
  31                 return -1;
  32         }
  33
  34         oui = WPA_GET_BE24(pos);
  35         switch (oui) {
  36         case OUI_MICROSOFT:
  37                 /* Microsoft/Wi-Fi information elements are further typed and
  38                  * subtyped */
  39                 switch (pos[3]) {
  40                 case 1:
  41                         /* Microsoft OUI (00:50:F2) with OUI Type 1:
  42                          * real WPA information element */
  43                         elems->wpa_ie = pos;
  44                         elems->wpa_ie_len = elen;
  45                         break;
  46                 case WMM_OUI_TYPE:
  47                         /* WMM information element */
  48                         if (elen < 5) {
  49                                 wpa_printf(MSG_MSGDUMP, "short WMM "
  50                                            "information element ignored "
  51                                            "(len=%lu)",
  52                                            (unsigned long) elen);
  53                                 return -1;
  54                         }
  55                         switch (pos[4]) {
  56                         case WMM_OUI_SUBTYPE_INFORMATION_ELEMENT:
  57                         case WMM_OUI_SUBTYPE_PARAMETER_ELEMENT:
  58                                 /*
  59                                  * Share same pointer since only one of these
  60                                  * is used and they start with same data.
  61                                  * Length field can be used to distinguish the
  62                                  * IEs.
  63                                  */
  64                                 elems->wmm = pos;
  65                                 elems->wmm_len = elen;
  66                                 break;
  67                         case WMM_OUI_SUBTYPE_TSPEC_ELEMENT:
  68                                 elems->wmm_tspec = pos;
  69                                 elems->wmm_tspec_len = elen;
  70                                 break;
  71                         default:
  72                                 wpa_printf(MSG_EXCESSIVE, "unknown WMM "
  73                                            "information element ignored "
  74                                            "(subtype=%d len=%lu)",
  75                                            pos[4], (unsigned long) elen);
  76                                 return -1;
  77                         }
  78                         break;
  79                 case 4:
  80                         /* Wi-Fi Protected Setup (WPS) IE */
  81                         elems->wps_ie = pos;
  82                         elems->wps_ie_len = elen;
  83                         break;
  84                 default:
  85                         wpa_printf(MSG_EXCESSIVE, "Unknown Microsoft "
  86                                    "information element ignored "
  87                                    "(type=%d len=%lu)",
  88                                    pos[3], (unsigned long) elen);
  89                         return -1;
  90                 }
  91                 break;
  92
  93         case OUI_WFA:
  94                 switch (pos[3]) {
  95                 case P2P_OUI_TYPE:
  96                         /* Wi-Fi Alliance - P2P IE */
  97                         elems->p2p = pos;
  98                         elems->p2p_len = elen;
  99                         break;
 100                 case WFD_OUI_TYPE:
 101                         /* Wi-Fi Alliance - WFD IE */
 102                         elems->wfd = pos;
 103                         elems->wfd_len = elen;
 104                         break;
 105                 case HS20_INDICATION_OUI_TYPE:
 106                         /* Hotspot 2.0 */
 107                         elems->hs20 = pos;
 108                         elems->hs20_len = elen;
 109                         break;
 110                 default:
 111                         wpa_printf(MSG_MSGDUMP, "Unknown WFA "
 112                                    "information element ignored "
 113                                    "(type=%d len=%lu)\n",
 114                                    pos[3], (unsigned long) elen);
 115                         return -1;
 116                 }
 117                 break;
 118
 119         case OUI_BROADCOM:
 120                 switch (pos[3]) {
 121                 case VENDOR_HT_CAPAB_OUI_TYPE:
 122                         elems->vendor_ht_cap = pos;
 123                         elems->vendor_ht_cap_len = elen;
 124                         break;
 125                 default:
 126                         wpa_printf(MSG_EXCESSIVE, "Unknown Broadcom "
 127                                    "information element ignored "
 128                                    "(type=%d len=%lu)",
 129                                    pos[3], (unsigned long) elen);
 130                         return -1;
 131                 }
 132                 break;
 133
 134         default:
 135                 wpa_printf(MSG_EXCESSIVE, "unknown vendor specific "
 136                            "information element ignored (vendor OUI "
 137                            "%02x:%02x:%02x len=%lu)",
 138                            pos[0], pos[1], pos[2], (unsigned long) elen);
 139                 return -1;
 140         }
 141
 142         return 0;
 143 }
 144
 145
 146 /**
 147  * ieee802_11_parse_elems - Parse information elements in management frames
 148  * @start: Pointer to the start of IEs
 149  * @len: Length of IE buffer in octets
 150  * @elems: Data structure for parsed elements
 151  * @show_errors: Whether to show parsing errors in debug log
 152  * Returns: Parsing result
 153  */
 154 ParseRes ieee802_11_parse_elems(const u8 *start, size_t len,
 155                                 struct ieee802_11_elems *elems,
 156                                 int show_errors)
 157 {
 158         size_t left = len;
 159         const u8 *pos = start;
 160         int unknown = 0;
 161
 162         os_memset(elems, 0, sizeof(*elems));
 163
 164         while (left >= 2) {
 165                 u8 id, elen;
 166
 167                 id = *pos++;
 168                 elen = *pos++;
 169                 left -= 2;
 170
 171                 if (elen > left) {
 172                         if (show_errors) {
 173                                 wpa_printf(MSG_DEBUG, "IEEE 802.11 element "
 174                                            "parse failed (id=%d elen=%d "
 175                                            "left=%lu)",
 176                                            id, elen, (unsigned long) left);
 177                                 wpa_hexdump(MSG_MSGDUMP, "IEs", start, len);
 178                         }
 179                         return ParseFailed;
 180                 }
 181
 182                 switch (id) {
 183                 case WLAN_EID_SSID:
 184                         elems->ssid = pos;
 185                         elems->ssid_len = elen;
 186                         break;
 187                 case WLAN_EID_SUPP_RATES:
 188                         elems->supp_rates = pos;
 189                         elems->supp_rates_len = elen;
 190                         break;
 191                 case WLAN_EID_FH_PARAMS:
 192                         elems->fh_params = pos;
 193                         elems->fh_params_len = elen;
 194                         break;
 195                 case WLAN_EID_DS_PARAMS:
 196                         elems->ds_params = pos;
 197                         elems->ds_params_len = elen;
 198                         break;
 199                 case WLAN_EID_CF_PARAMS:
 200                         elems->cf_params = pos;
 201                         elems->cf_params_len = elen;
 202                         break;
 203                 case WLAN_EID_TIM:
 204                         elems->tim = pos;
 205                         elems->tim_len = elen;
 206                         break;
 207                 case WLAN_EID_IBSS_PARAMS:
 208                         elems->ibss_params = pos;
 209                         elems->ibss_params_len = elen;
 210                         break;
 211                 case WLAN_EID_CHALLENGE:
 212                         elems->challenge = pos;
 213                         elems->challenge_len = elen;
 214                         break;
 215                 case WLAN_EID_ERP_INFO:
 216                         elems->erp_info = pos;
 217                         elems->erp_info_len = elen;
 218                         break;
 219                 case WLAN_EID_EXT_SUPP_RATES:
 220                         elems->ext_supp_rates = pos;
 221                         elems->ext_supp_rates_len = elen;
 222                         break;
 223                 case WLAN_EID_VENDOR_SPECIFIC:
 224                         if (ieee802_11_parse_vendor_specific(pos, elen,
 225                                                              elems,
 226                                                              show_errors))
 227                                 unknown++;
 228                         break;
 229                 case WLAN_EID_RSN:
 230                         elems->rsn_ie = pos;
 231                         elems->rsn_ie_len = elen;
 232                         break;
 233                 case WLAN_EID_PWR_CAPABILITY:
 234                         elems->power_cap = pos;
 235                         elems->power_cap_len = elen;
 236                         break;
 237                 case WLAN_EID_SUPPORTED_CHANNELS:
 238                         elems->supp_channels = pos;
 239                         elems->supp_channels_len = elen;
 240                         break;
 241                 case WLAN_EID_MOBILITY_DOMAIN:
 242                         elems->mdie = pos;
 243                         elems->mdie_len = elen;
 244                         break;
 245                 case WLAN_EID_FAST_BSS_TRANSITION:
 246                         elems->ftie = pos;
 247                         elems->ftie_len = elen;
 248                         break;
 249                 case WLAN_EID_TIMEOUT_INTERVAL:
 250                         elems->timeout_int = pos;
 251                         elems->timeout_int_len = elen;
 252                         break;
 253                 case WLAN_EID_HT_CAP:
 254                         elems->ht_capabilities = pos;
 255                         elems->ht_capabilities_len = elen;
 256                         break;
 257                 case WLAN_EID_HT_OPERATION:
 258                         elems->ht_operation = pos;
 259                         elems->ht_operation_len = elen;
 260                         break;
 261                 case WLAN_EID_VHT_CAP:
 262                         elems->vht_capabilities = pos;
 263                         elems->vht_capabilities_len = elen;
 264                         break;
 265                 case WLAN_EID_VHT_OPERATION:
 266                         elems->vht_operation = pos;
 267                         elems->vht_operation_len = elen;
 268                         break;
 269                 case WLAN_EID_LINK_ID:
 270                         if (elen < 18)
 271                                 break;
 272                         elems->link_id = pos;
 273                         break;
 274                 case WLAN_EID_INTERWORKING:
 275                         elems->interworking = pos;
 276                         elems->interworking_len = elen;
 277                         break;
 278                 case WLAN_EID_EXT_CAPAB:
 279                         elems->ext_capab = pos;
 280                         elems->ext_capab_len = elen;
 281                         break;
 282                 case WLAN_EID_BSS_MAX_IDLE_PERIOD:
 283                         if (elen < 3)
 284                                 break;
 285                         elems->bss_max_idle_period = pos;
 286                         break;
 287                 default:
 288                         unknown++;
 289                         if (!show_errors)
 290                                 break;
 291                         wpa_printf(MSG_MSGDUMP, "IEEE 802.11 element parse "
 292                                    "ignored unknown element (id=%d elen=%d)",
 293                                    id, elen);
 294                         break;
 295                 }
 296
 297                 left -= elen;
 298                 pos += elen;
 299         }
 300
 301         if (left)
 302                 return ParseFailed;
 303
 304         return unknown ? ParseUnknown : ParseOK;
 305 }
 306
 307
 308 int ieee802_11_ie_count(const u8 *ies, size_t ies_len)
 309 {
 310         int count = 0;
 311         const u8 *pos, *end;
 312
 313         if (ies == NULL)
 314                 return 0;
 315
 316         pos = ies;
 317         end = ies + ies_len;
 318
 319         while (pos + 2 <= end) {
 320                 if (pos + 2 + pos[1] > end)
 321                         break;
 322                 count++;
 323                 pos += 2 + pos[1];
 324         }
 325
 326         return count;
 327 }
 328
 329
 330 struct wpabuf * ieee802_11_vendor_ie_concat(const u8 *ies, size_t ies_len,
 331                                             u32 oui_type)
 332 {
 333         struct wpabuf *buf;
 334         const u8 *end, *pos, *ie;
 335
 336         pos = ies;
 337         end = ies + ies_len;
 338         ie = NULL;
 339
 340         while (pos + 1 < end) {
 341                 if (pos + 2 + pos[1] > end)
 342                         return NULL;
 343                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 344                     WPA_GET_BE32(&pos[2]) == oui_type) {
 345                         ie = pos;
 346                         break;
 347                 }
 348                 pos += 2 + pos[1];
 349         }
 350
 351         if (ie == NULL)
 352                 return NULL; /* No specified vendor IE found */
 353
 354         buf = wpabuf_alloc(ies_len);
 355         if (buf == NULL)
 356                 return NULL;
 357
 358         /*
 359          * There may be multiple vendor IEs in the message, so need to
 360          * concatenate their data fields.
 361          */
 362         while (pos + 1 < end) {
 363                 if (pos + 2 + pos[1] > end)
 364                         break;
 365                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 366                     WPA_GET_BE32(&pos[2]) == oui_type)
 367                         wpabuf_put_data(buf, pos + 6, pos[1] - 4);
 368                 pos += 2 + pos[1];
 369         }
 370
 371         return buf;
 372 }
 373
 374
 375 const u8 * get_hdr_bssid(const struct ieee80211_hdr *hdr, size_t len)
 376 {
 377         u16 fc, type, stype;
 378
 379         /*
 380          * PS-Poll frames are 16 bytes. All other frames are
 381          * 24 bytes or longer.
 382          */
 383         if (len < 16)
 384                 return NULL;
 385
 386         fc = le_to_host16(hdr->frame_control);
 387         type = WLAN_FC_GET_TYPE(fc);
 388         stype = WLAN_FC_GET_STYPE(fc);
 389
 390         switch (type) {
 391         case WLAN_FC_TYPE_DATA:
 392                 if (len < 24)
 393                         return NULL;
 394                 switch (fc & (WLAN_FC_FROMDS | WLAN_FC_TODS)) {
 395                 case WLAN_FC_FROMDS | WLAN_FC_TODS:
 396                 case WLAN_FC_TODS:
 397                         return hdr->addr1;
 398                 case WLAN_FC_FROMDS:
 399                         return hdr->addr2;
 400                 default:
 401                         return NULL;
 402                 }
 403         case WLAN_FC_TYPE_CTRL:
 404                 if (stype != WLAN_FC_STYPE_PSPOLL)
 405                         return NULL;
 406                 return hdr->addr1;
 407         case WLAN_FC_TYPE_MGMT:
 408                 return hdr->addr3;
 409         default:
 410                 return NULL;
 411         }
 412 }
 413
 414
 415 int hostapd_config_wmm_ac(struct hostapd_wmm_ac_params wmm_ac_params[],
 416                           const char *name, const char *val)
 417 {
 418         int num, v;
 419         const char *pos;
 420         struct hostapd_wmm_ac_params *ac;
 421
 422         /* skip 'wme_ac_' or 'wmm_ac_' prefix */
 423         pos = name + 7;
 424         if (os_strncmp(pos, "be_", 3) == 0) {
 425                 num = 0;
 426                 pos += 3;
 427         } else if (os_strncmp(pos, "bk_", 3) == 0) {
 428                 num = 1;
 429                 pos += 3;
 430         } else if (os_strncmp(pos, "vi_", 3) == 0) {
 431                 num = 2;
 432                 pos += 3;
 433         } else if (os_strncmp(pos, "vo_", 3) == 0) {
 434                 num = 3;
 435                 pos += 3;
 436         } else {
 437                 wpa_printf(MSG_ERROR, "Unknown WMM name '%s'", pos);
 438                 return -1;
 439         }
 440
 441         ac = &wmm_ac_params[num];
 442
 443         if (os_strcmp(pos, "aifs") == 0) {
 444                 v = atoi(val);
 445                 if (v < 1 || v > 255) {
 446                         wpa_printf(MSG_ERROR, "Invalid AIFS value %d", v);
 447                         return -1;
 448                 }
 449                 ac->aifs = v;
 450         } else if (os_strcmp(pos, "cwmin") == 0) {
 451                 v = atoi(val);
 452                 if (v < 0 || v > 12) {
 453                         wpa_printf(MSG_ERROR, "Invalid cwMin value %d", v);
 454                         return -1;
 455                 }
 456                 ac->cwmin = v;
 457         } else if (os_strcmp(pos, "cwmax") == 0) {
 458                 v = atoi(val);
 459                 if (v < 0 || v > 12) {
 460                         wpa_printf(MSG_ERROR, "Invalid cwMax value %d", v);
 461                         return -1;
 462                 }
 463                 ac->cwmax = v;
 464         } else if (os_strcmp(pos, "txop_limit") == 0) {
 465                 v = atoi(val);
 466                 if (v < 0 || v > 0xffff) {
 467                         wpa_printf(MSG_ERROR, "Invalid txop value %d", v);
 468                         return -1;
 469                 }
 470                 ac->txop_limit = v;
 471         } else if (os_strcmp(pos, "acm") == 0) {
 472                 v = atoi(val);
 473                 if (v < 0 || v > 1) {
 474                         wpa_printf(MSG_ERROR, "Invalid acm value %d", v);
 475                         return -1;
 476                 }
 477                 ac->admission_control_mandatory = v;
 478         } else {
 479                 wpa_printf(MSG_ERROR, "Unknown wmm_ac_ field '%s'", pos);
 480                 return -1;
 481         }
 482
 483         return 0;
 484 }